Ashish Diwan

BMP-7 in Combination with Estrogen Enhances Bone Formation in a Fracture Callus Explant Culture

Publisher: Tohoku University Medical Press

Date: 2010

DOI: 10.1620/TJEM.221.61

Abstract: In postmenopausal women, estrogen withdrawal results in decrease in bone density or osteoporosis. Osteoporosis leads to fracture and retards bone-healing response. Bone morphogenetic protein-7 (BMP-7), a member of the transforming-growth factor-beta superfamily, has been shown as a promising candidate that stimulates bone growth in its application to fracture healing. The purpose of this study was to determine whether BMP-7 could enhance bone formation in the absence of estrogen. Female rats underwent a controlled closed fracture at the midshaft of the right femur. The callus tissues were harvested from the fracture site eight days following the fracture, and were cultured in serum-free media. The explanted callus tissues were then treated with BMP-7, estrogen (E2) or both. We assessed bone formation by measuring alkaline phosphatase (AP) activity, expression of an osteogenic transcription factor, Runt-related transcription factor-2 (Runx2), production of nitric oxide (NO), and calcium mineralization. Supplementation of serum-free cultures with BMP-7 alone increased cell proliferation by twofold, caused a 6.5-fold increase in AP activity, and enhanced calcium mineralization after 48 h. Moreover, BMP-7 in combination with E2 caused a 8.2-fold increase in the AP activity. Runx2 protein expression was increased following stimulation with BMP-7 and E2. Interestingly, E2 induced the amount of NO production by twofold, whereas BMP-7 did not, either alone or with E2. Thus, BMP-7 could enhance early and late markers of bone fracture healing in callus explant cultures, except for NO. BMP-7 could be a promising growth factor in the treatment of fractures as a consequence of osteoporosis.

Restoration of compressive loading properties of lumbar discs with a nucleus implant—a finite element analysis study

Publisher: Elsevier BV

Date: 07-2010

DOI: 10.1016/J.SPINEE.2010.04.015

Abstract: Discectomy is a common procedure for treating sciatica. However, both the operation and preceding herniated disc alter the biomechanical properties of the spinal segment. The disc mechanics are also altered in patients with chronic contained herniation. The biomechanical properties of the disc can potentially be restored with an elastomeric nucleus replacement implanted via minimally invasive surgery. The purpose of this study was to determine whether the compressive characteristics of the intervertebral disc after a nucleotomy can be restored with an elastomeric nucleus replacement. A finite element model of the L4-L5 intervertebral disc was created to investigate the effect of the implantation of an elastomeric nucleus replacement on the biomechanical properties of the disc under axial loading. A L4-L5 physiologic intervertebral disc model was constructed and then modified to contain a range by volume of nucleotomies and nucleus replacements. The material properties of the nucleus replacement were based on experimental data for an elastomeric implant. The compressive stiffness, radial annular bulge, and stress distribution of the nucleotomy and nucleus replacement models were investigated under displacement-controlled loading. Removal of nucleus pulposus from the physiologic disc reduced the force necessary to compress the disc 2 mm by 50%, altered the von Mises stress distribution, and reduced the outward radial annular bulge. Replacing the natural nucleus pulposus of the physiologic disc with an artificial nucleus reduced the force required to compress the disc 2 mm by 10%, indicating a restoration of disc compressive stiffness. The von Mises stress distribution and annular bulge observed in the disc with an artificial nucleus were similar to that observed in the physiologic disc. This study demonstrates that despite having different material properties, a nucleus replacement implant can restore the axial compressive mechanical properties of a disc after a discectomy. The implant carries compressive load and transfers the load into annular hoop stress.

Expression and functional roles of estrogen receptor GPR30 in human intervertebral disc

Publisher: Elsevier BV

Date: 04-2016

DOI: 10.1016/J.JSBMB.2016.01.012

Abstract: Estrogen withdrawal, a characteristic of female aging, is associated with age-related intervertebral disc (IVD) degeneration. The function of estrogen is mediated by two classic nuclear receptors, estrogen receptor (ER)-α and -β, and a membrane bound G-protein-coupled receptor 30 (GPR30). To date, the expression and function of GPR30 in human spine is poorly understood. This study aimed to evaluate GPR30 expression in IVD, and its role in estrogen-related regulation of proliferation and apoptosis of disc nucleus pulposus (NP) cells. GPR30 expression was examined in 30 human adult NP and 9 fetal IVD. Results showed that GPR30 was expressed in NP cells at both mRNA and protein levels. In human fetal IVD, GPR30 protein was expressed in the NP at 12-14 weeks gestation, but was undetectable at 8-11 weeks. The effect of 17β-estradiol (E2) on GPR30-mediated proliferation and interleukin-1β (IL-1β)-induced apoptosis of NP cells was investigated. Cultured NP cells were treated with or without E2, GPR30 antagonist G36, and ER antagonist ICI 182,780. NP cell viability was tested by MTS assay. Apoptosis was determined by flow cytometry using fluorescence labeled annexin-V, TUNEL assay and immumnocytochemical staining of activated caspase-3. E2 enhanced cell proliferation and prevented IL-1β-induced cell death, but the effect was partially blocked by G36 and completely abrogated by a combination of ICI 182,780 and G36. This study demonstrates that GPR30 is expressed in human IVD to transmit signals triggering E2-induced NP cell proliferation and protecting against IL-1β-induced apoptosis. The effects of E2 on NP cells require both GPR30 and classic estrogen receptors.

Advanced Strategies for the Regeneration of Lumbar Disc Annulus Fibrosus

Publisher: MDPI AG

Date: 10-07-2020

DOI: 10.3390/IJMS21144889

Abstract: Damage to the annulus fibrosus (AF), the outer region of the intervertebral disc (IVD), results in an undesirable condition that may accelerate IVD degeneration causing low back pain. Despite intense research interest, attempts to regenerate the IVD have failed so far and no effective strategy has translated into a successful clinical outcome. Of particular significance, the failure of strategies to repair the AF has been a major drawback in the regeneration of IVD and nucleus replacement. It is unlikely to secure regenerative mediators (cells, genes, and biomolecules) and artificial nucleus materials after injection with an unsealed AF, as IVD is exposed to significant load and large deformation during daily activities. The AF defects strongly change the mechanical properties of the IVD and activate catabolic routes that are responsible for accelerating IVD degeneration. Therefore, there is a strong need to develop effective therapeutic strategies to prevent or reconstruct AF damage to support operational IVD regenerative strategies and nucleus replacement. By the way of this review, repair and regenerative strategies for AF reconstruction, their current status, challenges ahead, and future outlooks were discussed.

Anatomy of filamentary threshold switching in amorphous niobium oxide

Publisher: IOP Publishing

Date: 11-07-2018

DOI: 10.1088/1361-6528/AACEE4

Abstract: The threshold switching behavior of Pt/NbO

Understanding composite negative differential resistance in niobium oxide memristors

Publisher: IOP Publishing

Date: 07-12-2021

DOI: 10.1088/1361-6463/AC3BF4

Abstract: Volatile memristors, or threshold switching devices, exhibit a erse range of negative differential resistance (NDR) characteristics under current-controlled operation and understanding the origin of these responses is of great importance for exploring their potential as nano-scale oscillators for neuromorphic computing. Here we use a previously developed two-zone, parallel memristor model to undertake a systematic analysis of NDR modes in two-terminal metal-oxide-metal devices. The model assumes that the non-uniform current distribution associated with filamentary conduction can be represented by a high current density core and a lower current-density shell where the core is assumed to have a memristive response due to Poole-Frenkel conduction and the shell is represented by either a fixed resistor or a second memristive region. A detailed analysis of the electrical circuits is undertaken using a lumped-element thermal model of the core-shell structure, and is shown to reproduce continuous and discontinuous NDR responses, as well as more complex compound behaviour. Finally, an interesting double-window oscillation behaviour is predicted and experimentally verified for a device with compound NDR behaviour. These results clearly identify the origin of different NDR responses and provide a strong basis for designing devices with complex NDR characteristics.

Cartilage derived morphogenetic protein 2 – A potential therapy for intervertebral disc regeneration?

Publisher: Elsevier BV

Date: 03-2014

DOI: 10.1016/J.BIOLOGICALS.2013.12.003

Abstract: Low back pain is amongst the top ten risk factors that contribute to disability, ranking higher than diabetes and mental health disease globally as a contributor to years lost to disability (YLD), and escalating as Western societies age. Abundant evidence suggests that intervertebral disc (IVD) damage is central to the origin of pain in the spine. IVD degeneration involves the progressive deterioration of the highly organized disc tissue extracellular matrix, losing its elasticity and hence its' cushioning ability for the spine. Cartilage derived morphogenetic protein-2 (CDMP2) is a small peptide morphogen. Naturally occurring mutations segregate with skeletal defects in IVD development. CDMP2 signalling influences chondrogenic tissue determination, retards osteogenic tissue development and is crucial to early dorso-ventral axis defining events in zebrafish and Xenopus laevis. The potential of biological treatments to offer cutting edge early intervention, tissue regeneration and to preserve spinal motion segments shows great promise. The unique qualities of CDMP2 in IVD tissue formation, delineating discal matrix from vertebral bone, may prove adaptable in therapeutic applications to early discal degeneration. Here we explore the prevalence and origin of backache, the biology of CDMP2 and its potential application as an early intervention to arrest the disc degeneration sequelae.

Bone Scans Are Reliable for the Identification of Lumbar Disk and Facet Pathology

Publisher: SAGE Publications

Date: 25-10-2014

DOI: 10.1055/S-0034-1394298

Abstract: Surgeon survey. To evaluate the reliability of bone single-photon emission computed tomography (SPECT) versus bone SPECT images co-registered with computed tomography (bone SPECT-CT) by analyzing interobserver agreement for identification of the anatomical location of technetium 99m -labeled oxidronate uptake in the lumbar disk and/or facet joint. Seven spine surgeons interpreted 20 bone scans: 10 conventional black-and-white tomograms (bone SPECT) and 10 color-graded bone SPECT-CT scans. Each surgeon was asked to identify the location of any diagnostically relevant uptake in the disk and/or facet joint between L1 and S1. Reliability was evaluated using the free-marginal kappa statistic, and the level of agreement was assessed using the Landis and Koch interpretation. Conventional bone SPECT scans and bone SPECT-CT scans were reliable for the identification of diagnostically relevant uptake, with bone SPECT-CT having higher reliability (kappa = 0.72) than bone SPECT alone (0.59). Bone SPECT and bone SPECT-CT were also reliable in identifying disk pathology, with kappa values of 0.72 and 0.81, respectively. However, bone SPECT-CT was more reliable (0.81) than bone SPECT (0.60) when identifying facet disease. For the identification of disk pathology, it is reasonable to use either conventional bone SPECT or bone SPECT-CT however, bone SPECT-CT is more reliable for facet joint pathology.

Unusual cause of third-body wear in total hip arthroplasty

Publisher: Elsevier BV

Date: 08-1997

DOI: 10.1016/S0883-5403(97)90186-8

Abstract: A case of severe osteolysis caused by third-body wear using a Harris-Galante II cup (Zimmer, Warsaw, IN) is reported. The prosthesis was inserted in a 23-year-old man 4.5 years ago. At revision, 3 triangular tynes of the acetabular shell rim were found embedded in the polyethylene liner.

Current Localization and Redistribution as the Basis of Discontinuous Current Controlled Negative Differential Resistance in NbO _x

Publisher: Wiley

Date: 09-10-2019

DOI: 10.1002/ADFM.201906731

Letters

Publisher: Ovid Technologies (Wolters Kluwer Health)

Date: 05-2014

DOI: 10.1097/BRS.0000000000000310

Linear optical properties of Ge nanocrystals in silica

Publisher: AIP Publishing

Date: 08-10-2001

DOI: 10.1063/1.1409591

Abstract: The absorption and extinction spectra of Ge nanocrystals in silica formed by ion implantation are studied using photothermal deflection and transmission spectroscopies. It is found that scattering makes a significant contribution to the extinction spectrum, d ing the spectral features and resulting in a Rayleigh scattering-like ω4 dependence. In contrast, the spectra measured by photothermal deflection clearly show features such as the E1/E1+Δ1 transitions. The Tauc gap is extracted to be ∼0.7±0.1 eV.

Coupling dynamics of Nb/Nb₂O₅relaxation oscillators

Publisher: IOP Publishing

Date: 20-02-2017

DOI: 10.1088/1361-6528/AA5DE0

Abstract: The coupling dynamics of capacitively coupled Nb/Nb

Backing up the stories: The psychological and social costs of chronic low-back pain

Publisher: International Journal of Spine Surgery

Date: 12-2013

DOI: 10.1016/J.IJSP.2013.02.001

Bone morphogenetic protein-7 accelerates fracture healing in osteoporotic rats

Publisher: Springer Science and Business Media LLC

Date: 12-2013

DOI: 10.4103/0019-5413.121569

Morphological characteristics of the kangaroo lumbar intervertebral discs and comparison with other animal models used in spine research

Publisher: Springer Science and Business Media LLC

Date: 25-06-2019

DOI: 10.1007/S00586-019-06044-8

Abstract: Animal models are frequently used to elucidate pathomechanism and pathophysiology of various disorders of the human intervertebral disc (IVD) and also to develop therapeutic approaches. Here we report morphological characteristics of the kangaroo lumbar IVDs and compare them with other animal models used in spine research. Twenty-five fresh-frozen cadaveric lumbar spines (T12-S1) derived from kangaroo carcases (Macropus giganteus) of undetermined age were first scanned in a C-Arm X-ray machine. A photograph of the axial section of the disc including a calibrated metric scale was also acquired. The digital radiographs and photographs were processed in ImageJ to determine the axial and sagittal plane dimensions for the whole disc (WD) and the nucleus pulposus (NP) and the mid-sagittal disc height for all the lumbar levels. Our results suggest that the L6-S1 IVD in kangaroos is distinctly large compared with the upper lumbar IVDs. Based on previously published data, human lumbar IVDs are the largest of all the animal IVDs used in spine research, with camelid cervical IVDs being the closest relative in absolute dimensions (llamas: 78% in disc height, 40% in WD volume, and 38% in NP volume). Kangaroo L6-S1 IVD was approximately 51% in height, 20% in WD volume, and 20% in NP volume of the human lumbar IVD. We conclude that morphological similarities exist between a kangaroo and human lumbar IVD, especially with the lima bean shape in the axial plane, wedge shape in the sagittal plane, convexity at the cephalad endplates, and percentage volume occupied by the NP in the IVD. These slides can be retrieved under Electronic Supplementary Material.

Understanding modes of negative differential resistance in amorphous and polycrystalline vanadium oxides

Publisher: AIP Publishing

Date: 23-12-2020

DOI: 10.1063/5.0027875

Abstract: Metal–oxide–metal devices based on amorphous VOx are shown to exhibit one of two distinct negative differential resistance (NDR) characteristics depending on the maximum current employed for electroforming. For low compliance currents they exhibit a smooth S-type characteristic and have a temperature-dependent device resistance characterized by an activation energy of 0.25 eV, consistent with conduction in polycrystalline VO2, while for high compliance currents they exhibit an abrupt snap-back characteristic and a resistance characterized by an activation energy of 0.025 eV, consistent with conduction in oxygen deficient VOx. In both cases, the temperature dependence of the switching voltage implies that the conductivity change is due to the insulator–metal transition in VO2. From this analysis, it is concluded that electroforming at low currents creates a conductive filament comprised largely of polycrystalline VO2, while electroforming at high currents creates a composite structure comprised of VO2 and a conductive halo of oxygen deficient VOx. The effect of electroforming on the NDR mode is then explained with reference to a lumped element model of filamentary conduction that includes the effect of a parallel resistance created by the halo. These results provide new insight into the NDR response of vanadium-oxide-based devices and a basis for designing devices with specific characteristics.

Review article: Burnout in emergency medicine physicians

Publisher: Wiley

Date: 09-10-2013

DOI: 10.1111/1742-6723.12135

Abstract: Training and the practice of emergency medicine are stressful endeavours, placing emergency medicine physicians at risk of burnout. Burnout syndrome is associated with negative outcomes for patients, institutions and the physician. The aim of this review is to summarise the available literature on burnout among emergency medicine physicians and provide recommendations for future work in this field. A search of MEDLINE (1946-present) (search terms: 'Burnout, Professional' AND 'Emergency Medicine' AND 'Physicians' 'Stress, Psychological' AND 'Emergency Medicine' AND 'Physicians') and EMBASE (1988-present) (search terms: 'Burnout' AND 'Emergency Medicine' AND 'Physicians' 'Mental Stress' AND 'Emergency Medicine' AND 'Physicians') was performed. The authors focused on articles that assessed burnout among emergency medicine physicians. Most studies used the Maslach Burnout Inventory to quantify burnout, allowing for cross-study (and cross-country) comparisons. Emergency medicine has burnout levels in excess of 60% compared with physicians in general (38%). Despite this, most emergency medicine physicians (>60%) are satisfied with their jobs. Both work-related (hours of work, years of practice, professional development activities, non-clinical duties etc.) and non-work-related factors (age, sex, lifestyle factors etc.) are associated with burnout. Despite the heavy burnout rates among emergency medicine physicians, little work has been performed in this field. Factors responsible for burnout among various emergency medicine populations should be determined, and appropriate interventions designed to reduce burnout.

Clinical and Research MRI Techniques for Assessing Spinal Cord Integrity in Degenerative Cervical Myelopathy—A Scoping Review

Publisher: MDPI AG

Date: 18-10-2022

DOI: 10.3390/BIOMEDICINES10102621

Abstract: Background: Degenerative cervical myelopathy (DCM) manifests as the primary cause of spinal cord dysfunction and is non-traumatic, chronic and progressive in nature. Decompressive surgery is typically utilised to halt further disability and neurological dysfunction. The limitations of current diagnostic options surrounding assessment and prognostic potential render DCM still largely a clinical diagnosis. Aims: To outline the limitations of current diagnostic techniques, present evidence behind novel quantitative MRI (qMRI) techniques for assessing spinal cord integrity in DCM and suggest future directions. Method: Articles published up to November 2021 were retrieved from Medline, EMBASE and EBM using key search terms: spinal cord, spine, neck, MRI, magnetic resonance imaging, qMRI, T1, T2, T2*, R2*, DTI, diffusion tensor imaging, MT, magnetisation transfer, SWI, susceptibility weighted imaging, BOLD, blood oxygen level dependent, fMRI, functional magnetic resonance imaging, functional MRI, MRS, magnetic resonance spectroscopy. Results: A total of 2057 articles were retrieved with 68 articles included for analysis. The search yielded 2 articles on Quantitative T1 mapping which suggested higher T1 values in spinal cord of moderate-severe DCM 43 articles on DTI which indicated a strong correlation of fractional anisotropy and modified Japanese Orthopaedic Association scores 15 articles on fMRI (BOLD) which demonstrated positive correlation of functional connectivity and volume of activation of various connections in the brain with post-surgical recovery 6 articles on MRS which suggested that Choline/N-acetylaspartate (Cho/NAA) ratio presents the best correlation with DCM severity and 4 articles on MT which revealed a preliminary negative correlation of magnetisation transfer ratio with DCM severity. Notably, most studies were of low s le size with short timeframes within 6 months. Conclusions: Further longitudinal studies with higher s le sizes and longer time horizons are necessary to determine the full prognostic capacity of qMRI in DCM.

Role of nutritional supplementation in elderly patients with hip fractures

Publisher: Elsevier BV

Date: 2014

DOI: 10.1016/J.JOT.2013.11.003

Veillonella spondylodiscitis in a healthy 76-year-old lady

Publisher: Springer Science and Business Media LLC

Date: 16-06-2011

DOI: 10.1007/S00586-011-1871-X

Temperature dependent frequency tuning of NbOx relaxation oscillators

Publisher: AIP Publishing

Date: 13-11-2017

DOI: 10.1063/1.4999373

Abstract: This study investigates the temperature dependence of current-controlled negative differential resistance (CC-NDR) in Pt/NbOx/TiN devices and its effect on the dynamics of associated Pearson-Anson relaxation oscillators. The voltage range over which CC-NDR is observed decreases with increasing temperature such that no NDR is observed for temperatures above ∼380 K. Up to this temperature, relaxation oscillators exhibit voltage and temperature dependent oscillation frequencies in the range of 1 to 13 MHz. Significantly, the sensitivity of the frequency to temperature changes was found to be voltage-dependent, ranging from 39.6 kHz/K at a source voltage of 2 V to 110 kHz/K at a source voltage of 3 V, in the temperature range of 296–328 K. Such a behaviour provides insights into temperature tolerance and tuning variability for environmentally sensitive neuromorphic computing.

Intervertebral disc-on-a-chip: a precision engineered toolbox for low back pain studies.

Publisher: Elsevier BV

Date: 11-2023

DOI: 10.1016/J.TIBTECH.2023.04.009

Nanomechanical properties of sputter-deposited HfO2 and HfxSi1-xO2 thin films

Publisher: AIP Publishing

Date: 15-08-2011

DOI: 10.1063/1.3627155

Abstract: The mechanical properties of sputter-deposited HfO2 and HfxSi1-xO2 films were studied as a function of composition using nanoindentation. The elastic modulus and hardness were measured at room temperature for as-deposited films of varying Hf content and for films subjected to annealing at 1000 °C. The elastic modulus and hardness of as-deposited films were found to increase monotonically with increasing HfO2 content, with the hardness increasing from 5.0 ± 0.3 GPa for pure SiO2 to 8.4 ± 0.4 GPa for pure HfO2. All films were found to be harder after annealing at 1000 °C, with the increase for SiO2 films attributed to densification of the SiO2 network and that for the HfxSi1-xO2 films to a combination of phase separation, densification, and crystallization.

Growth differentiation factor‐6 attenuates inflammatory and pain‐related factors and degenerated disc‐induced pain behaviors in rat model

Publisher: Wiley

Date: 14-09-2020

DOI: 10.1002/JOR.24793

An Overview of Intervertebral Disc Degeneration Therapies and an Evaluation of the Chondrogenic and Chemotactic Potential of CDMP-2

Publisher: Trans Tech Publications, Ltd.

Date: 12-2013

DOI: 10.4028/WWW.SCIENTIFIC.NET/JBBTE.18.97

Abstract: Intervertebral disc degeneration creates a significant healthcare burden on industrialized Western society. Recent research into treatment options has highlighted numerous biological strategies to replenish the native disc cells with minimal invasion, although their effectiveness and safety are still under intense investigation. This review provides an outline of the key biological therapies under research currently, including stem cells, biomaterial scaffolds and signaling molecules. Particularly, the focus will be on CDMP-2, a signaling molecule that has been found to possess properties that are therapeutic to disc degeneration. The review will assess the evidence of the molecule’s chondrogenic and chemotactic effects on disc cells and evaluate areas for further research in determining its regenerative potential in the intervertebral disc.

Effect of Microstructure on Dielectric Breakdown in Amorphous HfO₂ Films

Publisher: Oxford University Press (OUP)

Date: 08-2014

DOI: 10.1017/S1431927614011659

Unconventional magnetism in all-carbon nanofoam

Publisher: American Physical Society (APS)

Date: 17-08-2004

DOI: 10.1103/PHYSREVB.70.054407

Influence of implantation damage on emitter recombination

Publisher: Elsevier BV

Date: 2014

DOI: 10.1016/J.EGYPRO.2014.08.080

Pedicle screw‐based posterior dynamic stabilizers for degenerative spine: In vitro biomechanical testing and clinical outcomes

Publisher: Wiley

Date: 31-12-2013

DOI: 10.1002/JBM.A.34986

Abstract: Dynamic stabilization in a degenerate symptomatic spine may be advantageous compared with conventional fusion procedures, as it helps preserve motion and minimizes redistribution of loads at instrumented and adjacent segments. This article presents a systematic review of biomechanical and clinical evidence available on some of the pedicle screw based posterior dynamic stabilization (PDS) devices. Using Medline, Embase, and Scopus online databases, we identified four pedicle-screw-PDS devices for which both, biomechanical testing and clinical follow-up data are available: Graf artificial ligaments, Isobar TTL, Polyetheretherketone rods, and Dynesys. The current state-of-the-art of pedicle-screw-PDS devices is far from achieving its desired biomechanical efficacy, which has resulted in a weak support for the posited clinical benefits. Although pedicle-screw-PDS devices are useful in salvaging a moderately degenerate functionally suboptimal disc, for severe disc degeneration cases fusion is still the preferred choice. We conclude that a pedicle-screw-PDS device should aim at restoring load sharing amongst spinal elements while preserving the qualitative and quantitative nature of spinal motion, especially minimize posterior shift of the helical axis of motion. More precise and objective assessment techniques need to be standardized for in vivo evaluation of intervertebral motion and load sharing amongst spinal elements across different pedicle-screw-PDS devices.

Polymethylmethacrylate bone cements and additives: A review of the literature

Publisher: Baishideng Publishing Group Inc.

Date: 2013

DOI: 10.5312/WJO.V4.I2.67

Leaping the hurdles in developing regenerative treatments for the intervertebral disc from preclinical to clinical

Publisher: Wiley

Date: 02-08-2018

DOI: 10.1002/JSP2.1027

Apoptosis in Skeletal Muscle Health and Conditions of Muscle Wasting

Publisher: CRC Press

Date: 19-07-2010

DOI: 10.1201/9781439845431-15

Cell therapy for disc degeneration—potentials and pitfalls

Publisher: Elsevier BV

Date: 2004

DOI: 10.1016/S0030-5898(03)00104-4

Nitric oxide regulates alkaline phosphatase activity in rat fracture callus explant cultures

Publisher: Informa UK Limited

Date: 04-2000

DOI: 10.1179/135100000101535438

Abstract: Nitric oxide (NO) is synthesised by a group of enzymes called nitric oxide synthases (NOS) and oxidizes to its stable end-products nitrite (NO2-) and nitrate (NO3-) We have previously reported in an in vivo rat model that NO is an important regulator for rat bone fracture healing. This study examines the effects of NO on alkaline phosphatase (ALP) activity in a rat fracture callus explant culture system. Explants of rat femoral fracture callus from days 4, 7, 14 and 28 post fracture induced NO2 release and ALP activity in a biphasic temporal manner, with the highest activity on day 7 and the lowest activity on day 14. Inhibition of NOS by co-incubation with an NOS inhibitor, S-(2-aminoethyl) isothiouronium bromide hydrobromide (AETU), inhibited ALP activity by an average of 50% at each time point (P <0.01). Supplementation with NO donor 3-morpholinosydnonomine hydrochloride (SIN-1) at low doses (25 and 0.025 microM) increased ALP activity by 20% (P < 0.01). ALP mRNA and histochemical ALP activity were localised to osteoblast-like and chondrocyte-like cells within fracture callus. The current study provides evidence that NO plays a regulatory role in ALP activity during rat fracture healing.

Tourette Syndrome and Klippel-Feil Anomaly in a Child with Chromosome 22q11 Duplication

Publisher: Hindawi Limited

Date: 2009

DOI: 10.1155/2009/361518

Abstract: This is the first case description of the association of Klippel-Feil Syndrome (KFS), Tourette Syndrome (TS), Motor Stereotypies, and Obsessive Compulsive Behavior, with chromosome 22q11.2 Duplication Syndrome (22q11DupS). Neuropsychiatric symptoms in persons with 22q11.2 deletion, including obsessive compulsiveness, anxiety, hyperactivity, and one prior case report of TS, have been attributed to low copy number effects on Catechol-O-Methyltransferase (COMT). However, the present unique case of 22q11DupS and TS suggests a more complex relationship involving another gene(s) at or near this locus.

Threaded Cortical Bone Dowels in Lumbosacral Arthrodesis

Publisher: Ovid Technologies (Wolters Kluwer Health)

Date: 09-2003

DOI: 10.1097/01.BLO.0000079445.64912.9F

Abstract: Lumbar fusion is a common spinal surgery, for which numerous devices have been developed to aid in segment stabilization. A threaded cortical bone dowel is a machined and processed bone allograft which is one such development. Threaded cortical bone dowels are attractive because of their osteoconductive nature and the opportunity to load them with osteogenic morselized bone autograft or osteoinductive growth factors, such as bone morphogenetic proteins. Although threaded cortical bone dowels have been in clinical use for more than 5 years, they have not been the subject of a comprehensive review. The current article covers the history, preparation, uses, safety, and efficacy of threaded cortical bone dowels in lumbosacral interbody fusion.

Heterogeneity in Klippel-Feil syndrome: a new classification.

Publisher: Springer Science and Business Media LLC

Date: 12-1998

DOI: 10.1007/S002470050511

Abstract: Klippel-Feil syndrome (KFS) is characterised by congenital vertebral fusion of the cervical spine and a wide spectrum of associated anomalies. KFS has often been considered a sporadic syndrome. However, since the publication of the original KFS classification early this century, a number of KFS families have indicated heterogeneity complicated by a broad range of variable expression. The two major objectives of this study were (1) to identify differences and similarities in the postnatal appearance, morphology, position and inheritance of vertebral fusions within and between KFS families and (2) to establish a new KFS classification focussed on KFS aetiology. Vertebral fusions were assessed via spinal radiography. Chromosomal karyotypes were performed using routine cytogenetics. The medical histories of three KFS families are presented. The postnatal time, position and appearance of vertebral fusions, associated anomalies and mode of inheritance were different for the three KFS families. Four classes of KFS are described in a comprehensive classification table that allays much of the uncertainty arising from KFS heterogeneity and variable expression. We have described four different KFS classes (KF1-4) within a comprehensive classification that addresses KFS genetic heterogeneity. The position of vertebral fusions in the cervical spine and their incidence within affected families are delineating features of KFS.

Nucleus Pulposus Cellular Longevity by Telomerase Gene Therapy

Publisher: Ovid Technologies (Wolters Kluwer Health)

Date: 05-2007

DOI: 10.1097/BRS.0B013E31805471A3

Formation of ordered arrays of gold particles by nanoindentation templating

Publisher: Wiley

Date: 22-10-2013

DOI: 10.1002/PSSR.201308156

BMP-13 Emerges as a Potential Inhibitor of Bone Formation

Publisher: Ivyspring International Publisher

Date: 2009

DOI: 10.7150/IJBS.5.192

Histologic Evaluation of the Efficacy of rhBMP-2 Compared With Autograft Bone in Sheep Spinal Anterior Interbody Fusion

Publisher: Ovid Technologies (Wolters Kluwer Health)

Date: 03-2002

DOI: 10.1097/00007632-200203150-00003

Abstract: The sheep anterior lumbar spinal fusion model was used to study the efficacy of recombinant human bone morphogenetic protein-2 (rhBMP-2)-collagen composite in comparison with autograft to enhance spinal interbody fusion. Comparisons were drawn from temporal radiographic and end-point biomechanical and histologic data. To analyze histologically the ability of rhBMP-2 to achieve complete arthrodesis between vertebral bodies. Studies using rhBMP for enhancement of anterior interbody fusion have used numerous endpoints. However, systematic histologic evaluation of the fusion has not been conducted. Twelve sheep underwent single-level anterior lumbar interbody fusion performed with a cylindrical fenestrated titanium interbody fusion device (INTER FIX, Medtronic Sofamor Danek, Inc., Memphis, TN). The device was filled either with rhBMP-2-collagen (n = 6) or autogenous iliac crest bone graft (n = 6). Radiologic evaluation was carried out at 2-month intervals, and all sheep were killed 6 months after surgery. Nondestructive biomechanical testing for stiffness to flexion, extension, and lateral bending moments, un-decalcified histology, and qualitative and quantitative histologic evaluation were performed. Radiographs revealed a bony bridge anterior to the cage in five of six rhBMP-2-treated animals, whereas it was present only in one of five in the autogenous bone graft group. Segments treated with rhBMP-2 were 20% stiffer in flexion than autograft-treated segments at 6 months. Six of six in the rhBMP-2 group and two of six in the autograft group showed complete fusion. There was a significantly higher rate of bony continuity observed at the fenestrations of the rhBMP-2 group. Three times more number of cage fenestrations in the rhBMP-2 group demonstrated "all-bone" when compared with the autograft group (P < 0.001). Further, the scar tissue in and around the autograft-treated cages was 16-fold more (P < 0.01) than that seen for rhBMP-2-treated cages. The study demonstrates that rhBMP-2 can lead to earlier radiologic fusion and a more consistent increased stiffness of the segments when compared with autograft in sheep anterior lumbar interbody fusion. Furthermore, a three times higher histologic fusion rate is attainable with significantly reduced fibrous tissue around the implant when rhBMP-2 is used.

Differentiation of Rodent Bone Marrow Mesenchymal Stem Cells into Intervertebral Disc-like Cells Following Coculture with Rat Disc Tissue

Publisher: Mary Ann Liebert Inc

Date: 09-2009

DOI: 10.1089/TEN.TEA.2008.0458

Intraoperative pressure sensors improve soft-tissue balance but not clinical outcomes in total knee arthroplasty: a multicentre randomized controlled trial.

Publisher: British Editorial Society of Bone & Joint Surgery

Date: 05-2022

DOI: 10.1302/0301-620X.104B5.BJJ-2021-1299.R2

Abstract: Intraoperative pressure sensors allow surgeons to quantify soft-tissue balance during total knee arthroplasty (TKA). The aim of this study was to determine whether using sensors to achieve soft-tissue balance was more effective than manual balancing in improving outcomes in TKA. A multicentre randomized trial compared the outcomes of sensor balancing (SB) with manual balancing (MB) in 250 patients (285 TKAs). The primary outcome measure was the mean difference in the four Knee injury and Osteoarthritis Outcome Score subscales (ΔKOOS 4 ) in the two groups, comparing the preoperative and two-year scores. Secondary outcomes included intraoperative balance data, additional patient-reported outcome measures (PROMs), and functional measures. There was no significant difference in ΔKOOS 4 between the two groups at two years (mean difference 0.4 points (95% confidence interval (CI) -4.6 to 5.4) p = 0.869), and multiple regression found that SB was not associated with a significant ΔKOOS 4 (0.2-point increase (95% CI -5.1 to 4.6) p = 0.924). There were no significant differences between groups in other PROMs. Six-minute walking distance was significantly increased in the SB group (mean difference 29 metres p = 0.015). Four-times as many TKAs were unbalanced in the MB group (36.8% MB vs 9.4% SB p 0.001). Irrespective of group assignment, no differences were found in any PROM when increasing ICPD thresholds defined balance. Despite improved quantitative soft-tissue balance, the use of sensors intraoperatively did not differentially improve the clinical or functional outcomes two years after TKA. These results question whether a more precisely balanced TKA that is guided by sensor data, and often achieved by more balancing interventions, will ultimately have a significant effect on clinical outcomes. Cite this article: Bone Joint J 2022 -B(5):604–612.

Detection and spatial mapping of conductive filaments in metal/oxide/metal cross-point devices using a thin photoresist layer

Publisher: AIP Publishing

Date: 11-02-2019

DOI: 10.1063/1.5084060

Abstract: A simple means of detecting and spatially mapping volatile and nonvolatile conductive filaments in metal/oxide/metal cross-point devices is introduced, and its application demonstrated. The technique is based on thermal discolouration of a thin photoresist layer deposited on the top electrode (TE) of the cross-point device and relies on the increase in temperature produced by local Joule heating of an underlying conductive filament. Finite element modelling of the temperature distribution and its dependencies shows that the maximum temperature at the TE hotoresist interface is particularly sensitive to the TE thickness. The technique is demonstrated on NbOx-based metal-oxide-metal cross-point devices with a 25 nm thick top (Pt) electrode, where it is used to undertake a statistical analysis of the filament location as a function of device area. This shows that filament formation is heterogeneous the majority of filaments form preferentially along the TE edge, and the fraction of these increases with the decreasing device area. Transmission electron microscopy of the top and bottom electrode edges is used to explain this observation and suggests that it is due to a reduction in the effective oxide thickness in this region.

Chronic low back pain: issues and management, part I

Publisher: Elsevier BV

Date: 04-2003

DOI: 10.1016/S0030-5898(03)00037-3

Mild (not severe) disc degeneration is implicated in the progression of bilateral L5 spondylolysis to spondylolisthesis

Publisher: Springer Science and Business Media LLC

Date: 02-04-2018

DOI: 10.1186/S12891-018-2011-0

The Effect of Running Exercise on Intervertebral Disc Extracellular Matrix Production in a Rat Model

Publisher: Ovid Technologies (Wolters Kluwer Health)

Date: 07-2010

DOI: 10.1097/BRS.0B013E3181E0F5BC

Forming-free bipolar resistive switching and quantum conductance in NiO/FTO structures

Publisher: IOP Publishing

Date: 04-09-2019

DOI: 10.1088/1361-6463/AB3AA4

Threshold switching and electrical self-oscillation in niobium oxide films

Publisher: AIP Publishing

Date: 28-09-2016

DOI: 10.1063/1.4963288

Abstract: Electrical self-sustained oscillations have been observed in a broad range of two-terminal systems and are of interest as possible building blocks for bio-inspired neuromorphic computing. In this work, we experimentally explore voltage-controlled oscillations in NbOx devices with a particular focus on understanding how the frequency and waveform are influenced by circuit parameters. We also introduce a finite element model of the device based on a Joule-heating induced insulator-metal transition. The electroformed device structure is represented by a cylindrical conductive channel (filament) comprised of NbO/NbO2 zones and surrounded by an Nb2O5−x matrix. The model is shown to reproduce the current-controlled negative differential resistance observed in measured current-voltage curves, and is combined with circuit elements to simulate the waveforms and dynamics of an isolated Pearson–Anson oscillator. Such modeling is shown to provide considerable insight into the relationship between the material response and device and circuit characteristics.

A novel tool to provide predictable alignment data irrespective of source and image quality acquired on mobile phones: what engineers can offer clinicians

Publisher: Springer Science and Business Media LLC

Date: 02-01-2020

DOI: 10.1007/S00586-019-06264-Y

Abstract: Existing automated spine alignment is based on original X-rays that are not applicable for teleradiology for spinal deformities patients. We aim to provide a novel automated vertebral segmentation method enabling accurate sagittal alignment detection, with no restrictions imposed by image quality or pathology type. A total of 428 optical images of original sagittal X-rays taken by smartphones or screenshots for consecutive patients attending our spine clinic were prospectively collected. Of these, 300 were randomly selected and their vertebrae were labelled with Labelme. The ground truth was specialists measured sagittal alignment parameters. Pre-trained Mask R-CNN was fine-tuned and trained to predict the vertebra level(s) on the remaining 128 testing cases. The sagittal alignment parameters including the thoracic kyphosis (TK), lumbar lordosis (LL) and sacral slope (SS) were auto-detected, based on the segmented vertebra. Dice similarity coefficient (DSC) and mean intersection over union (mIoU) were calculated to evaluate the accuracy of the predicted vertebra. The detected sagittal alignments were then quantitatively compared with the ground truth. The DSC was 84.6 ± 3.8% and mIoU was 72.1 ± 4.8% indicating accurate vertebra prediction. The sagittal alignments detected were all strongly correlated with the ground truth (p < 0.001). Standard errors of the estimated parameters had a small difference from the specialists' results (3.5° for TK and SS 3.4° for LL). This is the first study using fine-tuned Mask R-CNN to predict vertebral locations on optical images of X-rays accurately and automatically. We provide a novel alignment detection method that has a significant application on teleradiology aiding out-of-hospital consultations. These slides can be retrieved under Electronic Supplementary Material.

Thermal transport in metal-NbO_x-metal cross-point devices and its effect on threshold switching characteristics

Publisher: Royal Society of Chemistry (RSC)

Date: 2023

DOI: 10.1039/D3NR00173C

Abstract: The thickness and thermal conductivity of electrodes are shown to have a direct impact on the volatile threshold switching characteristics of NbO x -based memristors due to their effect on the temperature of the active volume.

GENE THERAPY FOR SPINE FUSION

Publisher: Elsevier BV

Date: 07-2000

DOI: 10.1016/S0030-5898(05)70165-6

Abstract: Gene therapy is a novel therapeutic modality for repair and regeneration of musculoskeletal tissues, including the spine. Various methods for therapeutic gene transfer are presented in this article. Several studies in which gene transfer has been used specifically to enhance spine fusion in animal models are reviewed.

The effect of annealing ambient on carrier recombination in boron implanted silicon

Publisher: Wiley

Date: 13-08-2014

DOI: 10.1002/PSSR.201409295

Reliability, validity and generalizability of multidimensional pain assessment tools used in postoperative adult patients

Publisher: Ovid Technologies (Wolters Kluwer Health)

Date: 06-09-2019

DOI: 10.11124/JBISRIR-2017-003819

Abstract: The objective of this review is to evaluate the measurement properties of multidimensional pain assessment tools for postoperative pain in adults. Effective postoperative pain management increases patient safety and satisfaction, and reduces healthcare costs. The most commonly used postoperative pain assessment tools only evaluate pain intensity, which is only one aspect of the sensory dimension of pain. Pain is a subjective phenomenon, and variability exists among patients. Efforts are underway to incorporate multidimensional assessment tools for postoperative pain assessment in clinical practice. Eligible studies will include postoperative patients aged 18 years and older from all surgical disciplines. Studies evaluating multidimensional assessment instruments for the measurement of postoperative pain during the first two weeks following surgery will be considered. Studies will include the following measurement properties of assessment tools as outcomes: reliability, validity and generalizability. MEDLINE, CINAHL, Embase, PsycINFO and Cochrane Trials (CENTRAL) will be searched, as well as ClinicalTrials.gov and multiple gray literature sources. There will be no limitations on publication date. Titles and abstracts will be screened by independent reviewers for inclusion. The full text of selected papers will be retrieved and assessed against the inclusion criteria. Two independent reviewers will assess papers for methodological quality using the COSMIN checklist, and papers with poor scores on relevant items will be excluded. Data will be extracted by two independent reviewers using a standardized data extraction tool. Statistical pooling will be performed, if possible.

The timing of surgery in lumbar disc prolapse: A systematic review

Publisher: Springer Science and Business Media LLC

Date: 04-2014

DOI: 10.4103/0019-5413.128740

Room temperature synthesis of HfO₂/HfO _x heterostructures by ion-implantation

Publisher: IOP Publishing

Date: 15-08-2018

DOI: 10.1088/1361-6528/AAD756

Abstract: Implantation of Hf films with oxygen ions is shown to be an effective means of fabricating high-quality HfO

A Kangaroo Spine Lumbar Motion Segment Model: Biomechanical Analysis of a Novel <i>In Situ</i> Curing Nucleus Replacement Device

Publisher: Trans Tech Publications, Ltd.

Date: 2011

DOI: 10.4028/WWW.SCIENTIFIC.NET/JBBTE.9.25

Abstract: This in vitro study compared the effects of nucleotomy alone, with nucleotomy then implantation with a novel nucleus replacement device (D3 device) in a single segment kangaroo spine model. This study utilised dynamic biaxial biomechanical testing of intact, nucleotomy and nucleus replacement implant conditions to evaluate the kinematic behaviour of the single segment kangaroo lumbar spine. Studies have examined the biomechanical efficacy of invasive treatments such as Total Disc Replacement and Intervertebral Fusion for the treatment of chronic low back pain, however no studies to date have investigated the biomechanical effects of a novel elastomeric compressive load sharing nucleus replacement device. Kangaroo lumbar spine motion segments with all musculature, ligamentous tissue and posterior elements removed, were tested in intact state prior to undergoing nucleotomy or nucleotomy then nucleus implantation using the D3 device. All specimens were tested in flexion-extension and lateral-bending Range of motion (ROM), Neutral Zone (NZ), Hysteresis (H), and Elastic Stiffness (ES) were evaluated. Nucleotomised motion segments demonstrated a 30% to 90% increase in ROM, NZ, H, but not ES for all Flexion-Extension testing conditions and in Lateral Bending test conditions when compared to intact state. Implantation of the nucleus replacement device demonstrated no significant difference when compared to intact state except for H during Lateral Bending testing conditions when compared to the intact state. Therefore, there was a significant increase in ROM, NZ, and H after Nucleotomy during Flexion-Extension motions and an increase in ROM alone during lateral bending motions in the single segment kangaroo spine model. These changes return to that of the intact state with the placement of a novel nucleus replacement device. Our data suggest that the D3 device tested can restore the kinematic changes of a degenerated disc represented by the nucleotomised single motion segment.

Optical absorption measurements of silica containing Si nanocrystals produced by ion implantation and thermal annealing

Publisher: AIP Publishing

Date: 25-02-2002

DOI: 10.1063/1.1454217

Abstract: Optical absorption spectra from silicon-implanted silica slides are shown to contain features due to optical interference. These features, which result from the modified refractive index profile produced by the implant, can readily lead to misinterpretation of absorption spectra. To demonstrate the importance of such effects, silica s les were implanted with 80, 400, and 600 keV Si ions to fluences in the range 0.6–3.0×1017 Si.cm−2 and annealed at 1100 °C for 1 h to form Si nanocrystals. Optical absorption/transmittance spectra from these s les show considerable structure that is characteristic of the particular implant conditions. This structure is shown to correlate with the transmittance of the s les as calculated from the modified refractive index profile for each implant. The lack of such structure in absorption spectra measured by photodeflection spectrometry is used to confirm this interpretation.

Localization of bone morphogenetic protein 13 in human intervertebral disc and its molecular and functional effects in vitro in 3D culture

Publisher: Wiley

Date: 14-07-2015

DOI: 10.1002/JOR.22965

Abstract: Our laboratory has demonstrated that bone morphogenetic protein 13 prevented the effects of annular injury in an ovine model, maintaining intervertebral disc height, cell numbers and increasing extracellular matrix production compared to degenerated controls. The present study sought to examine the molecular effects of bone morphogenetic protein 13 on human degenerated disc cells and localize its expression in both human degenerate and scoliotic disc tissue. Effect of bone morphogenetic protein 13 on human derived nucleus pulposus, annulus fibrosus and endplate cells cultured in alginate beads was evaluated by changes in proteoglycan and collagen content. Migratory potential of disc cells towards bone morphogenetic protein 13 was also examined. Bone morphogenetic protein 13 induced significant proteoglycan accumulation in nucleus (18%), annulus (21%) and endplate (23%) cells cultured in alginate beads (p<0.05) compared to controls. Further bone morphogenetic protein 13 increased collagen I and II protein expression in nucleus and endplate cells. Nucleus cells displayed a significant chemotactic response towards bone morphogenetic protein 13. The endogenous expression of bone morphogenetic protein 13 in degenerate disc tissue was not different to scoliotic disc. Bone morphogenetic protein 13 has the potential to enhance extracellular matrix accumulation and induce cell migration in certain disc cells.

Low-Variance Memristor-Based Multi-Level Ternary Combinational Logic

Publisher: Institute of Electrical and Electronics Engineers (IEEE)

Date: 06-2022

DOI: 10.1109/TCSI.2022.3151920

Mutations in GDF6 are associated with vertebral segmentation defects in Klippel-Feil syndrome

Publisher: Hindawi Limited

Date: 08-2008

DOI: 10.1002/HUMU.20741

Abstract: Klippel-Feil syndrome (KFS) is a congenital disorder of spinal segmentation distinguished by the bony fusion of anterior/cervical vertebrae. Scoliosis, mirror movements, otolaryngological, kidney, ocular, cranial, limb, and/or digit anomalies are often associated. Here we report mutations at the GDF6 gene locus in familial and sporadic cases of KFS including the recurrent missense mutation of an extremely conserved residue c.866T>C (p.Leu289Pro) in association with mirror movements and an inversion breakpoint downstream of the gene in association with carpal, tarsal, and vertebral fusions. GDF6 is expressed at the boundaries of the developing carpals, tarsals, and vertebrae and within the adult vertebral disc. GDF6 knockout mice are best distinguished by fusion of carpals and tarsals and GDF6 knockdown in Xenopus results in a high incidence of anterior axial defects consistent with a role for GDF6 in the etiology, ersity, and variability of KFS.

High Spatial Resolution Thermal Mapping of Volatile Switching in NbO_x-Based Memristor Using In Situ Scanning Thermal Microscopy

Publisher: American Chemical Society (ACS)

Date: 14-06-2022

DOI: 10.1021/ACSAMI.2C06870

Abstract: Temperature mapping by in situ thermoreflectance thermal imaging (TRTI) or midwave infrared spectroscopy has played an important role in understanding the origins of threshold switching and the effect of insulator-metal transitions in oxide-based memrsitive devices. In this study, we use scanning thermal microscopy (SThM) as an alternative thermal mapping technique that offers high spatial resolution imaging (∼100 nm) and is independent of material. Specifically, SThM is used to map the temperature distribution in NbO

Pathophysiological Correlation between Cigarette Smoking and Amyotrophic Lateral Sclerosis

Publisher: MDPI AG

Date: 20-04-2021

DOI: 10.3390/NEUROSCI2020008

Abstract: Cigarette smoke (CS) has been consistently demonstrated to be an environmental risk factor for amyotrophic lateral sclerosis (ALS), although the molecular pathogenic mechanisms involved are yet to be elucidated. Here, we propose different mechanisms by which CS exposure can cause sporadic ALS pathogenesis. Oxidative stress and neuroinflammation are widely implicated in ALS pathogenesis, with blood–spinal cord barrier disruption also recognised to be involved in the disease process. In addition, immunometabolic, epigenetic and microbiome alterations have been implicated in ALS recently. Identification of the underlying pathophysiological mechanisms that underpin CS-associated ALS will drive future research to be conducted into new targets for treatment.

Answer to the Letter to the Editor of Miao Yu et al. concerning “Is L5-S1 motion segment different from the rest? A radiographic kinematic assessment of 72 patients with chronic low back pain” by AB Sabnis et al. (Eur. Spine J; 27(5):1127–1135)

Publisher: Springer Science and Business Media LLC

Date: 22-06-2019

DOI: 10.1007/S00586-018-5675-0

Electric Field- and Current-Induced Electroforming Modes in NbO_x

Publisher: American Chemical Society (ACS)

Date: 28-01-2020

DOI: 10.1021/ACSAMI.9B20252

Abstract: Electroforming is used to initiate the memristive response in metal/oxide/metal devices by creating a filamentary conduction path in the oxide film. Here, we use a simple photoresist-based detection technique to map the spatial distribution of conductive filaments formed in Nb/NbO

Preoperative Magnetic Resonance Imaging Screening for a Surgical Decision Regarding the Approach for Anterior Spine Fusion at the Cervicothoracic Junction

Publisher: Ovid Technologies (Wolters Kluwer Health)

Date: 04-2002

DOI: 10.1097/00007632-200204010-00002

Abstract: In a study investigating the correlation between a set of designed criteria and judgments of surgical experience, 100 cervical magnetic resonance images from different patients were used. To demonstrate reliable and reproducible anatomic measurements that can aid spine surgeons in selecting surgical approaches for anterior spine fusion in the cervicothoracic region. Surgical approaches to the cervicothoracic junction vary among surgeons. Whereas sternotomy provides maximum exposure, less extensive approaches are preferred to minimize surgical trauma, provided surgical goals are not compromised. No quantitative criteria currently exist to determine before surgery the least invasive surgical approach for sufficiently exposing pertinent anatomy. Thirteen geometric variables designed to be clinically practical and to expose important anatomic relations were used to evaluate 100 sagittal scout cervical magnetic resonance image sequences. An experienced spine surgeon independently rated each image for the most appropriate surgical approach to the C5-T2 region. The ratings were tested for interrater reliability using a second spine surgeon. After testing for interrater and intrarater reliability, the geometric measurements were correlated with the surgeon's selected surgical approaches for each intervertebral segment (P < 0.05). Instrument manubrial thoracic distances, reflecting standardized heights of intervertebral discs above or below the superior tip of the manubrium, were the most reliable, reproducible, and correlative with the choice of surgical approach. All the measurements but one, the instrument manubrial thoracic distance for T1/T2, demonstrated interrater and intrarater reliability, with an interclass correlation of at least 0.70. The primary surgeon-investigator indicated the anterior approach with sternotomy (n = 3) or the transverse cervical approach (n = 97) for the C7/T1 exposure, and the anterior approach with sternotomy (n = 43) or the transverse cervical approach (n = 57) for the T1/T2 exposure. The interrater questionnaire reliability results indicated statistical agreement between the primary surgeon-investigator and the second cervical spine surgeon at all vertebral segments evaluated. Instrument manubrial thoracic distances showed the strongest significant correlation with the surgical approach, demonstrating a statistical power of 1. For the C7/T1 exposure, the instrument manubrial thoracic distance for C7/T1 was 1.9 +/- 2 cm (95% confidence interval [CI] = 1.41 to 2.22) for the transverse cervical approach, and -3.3 +/- 1.3 cm (95% CI = -4.79 to -1.75)] for the anterior approach with sternotomy. The instrument manubrial thoracic distance measurements for C5/C6, C6/C7, and T1/T2 also showed nonoverlapping 95% confidence intervals for the transverse cervical versus the anterior approach with sternotomy for the C7/T1 exposure. For the T1/T2 exposure, all four instrument manubrial thoracic distance measurements again showed statistically significant differences between approaches, with nonoverlapping 95% confidence intervals and a statistical power of 1. In addition, the measurements elaborating the anterior-to-posterior distance of the thoracic outlet and the measurements of the angle between the planes of the intervertebral disc and the sternum also showed statistically significant differences between approaches for the T1/T2 segment, with a statistical power of at least 0.9. Strong correlations exist between objective measurements and the choice of surgical approach for anterior spine fusion. Among investigated anatomic relations, the instrument manubrial thoracic distance correlated most reliably with the surgeons' choice of the anterior approach. Such objective measurements represent tools that cervical spine surgeons can use to determine the surgical approach.

What is the Rate of Revision Discectomies After Primary Discectomy on a National Scale?

Publisher: Ovid Technologies (Wolters Kluwer Health)

Date: 11-2017

DOI: 10.1007/S11999-017-5467-6

When is spinal pain “neuropathic”?

Publisher: Elsevier BV

Date: 2004

DOI: 10.1016/S0030-5898(03)00098-1

Post-traumatic thoracic scoliosis with rib head dislocation and intrusion into the spinal canal: a case report and review of literature

Publisher: Springer Science and Business Media LLC

Date: 21-02-2010

DOI: 10.1007/S00586-010-1321-1

Observation of a helium ion energy threshold for retention in tungsten exposed to hydrogen/helium mixture plasma

Publisher: IOP Publishing

Date: 16-08-2016

DOI: 10.1088/0029-5515/56/10/104002

Abstract: Helium retention is measured in tungsten s les exposed to mixed H/He plasma in the Magnum-PSI linear plasma device. It is observed that there is very little He retention below helium ion impact energies of 9.0 ± 1.4 eV, indicating the existence of a potential barrier which must be overcome for implantation to occur. The helium retention in s les exposed to plasma at temperatures K is strongly correlated with nano-bubble formation measured using grazing incidence small-angle x-ray scattering. The diameters of nano-bubbles were not found to increase with increasing helium concentration, indicating that additional helium must be accommodated by increasing the bubble concentration or an increase in bubble pressure. For some s les pre-irradiation with heavy ions of 2.0 MeV energy is investigated to simulate the effects of neutron damage. It is observed that nano-bubble sizes are comparable between s les pre-irradiated with heavy-ions, and those without heavy-ion pre-irradiation.

Cartilage Derived Morphogenetic Protein-2 Induces Cell Migration and Its Chondrogenic Potential in C28/I2 Cells

Publisher: International Journal of Spine Surgery

Date: 2015

DOI: 10.14444/2052

The use of electron Rutherford backscattering to characterize novel electronic materials as illustrated by a case study of sputter-deposited NbO x films

Publisher: Elsevier BV

Date: 12-2014

DOI: 10.1016/J.NIMB.2014.06.024

The molecular basis of intervertebral disk degeneration

Publisher: Elsevier BV

Date: 04-2003

DOI: 10.1016/S0030-5898(03)00026-9

Abstract: At present, the molecular evidence involved in the degeneration of the IVD is still in its primitive stage. In general, however, intrinsic, extrinsic, and generic factors all have shown a contribution to the initiation of degeneration. These factors may stimulate cytokines and directly or indirectly generate the cellular events thus far detected and observed. Such changes discussed have been the cellularity, matrix degradation, matrix quality, and synthesis of enzymes involved in the breakdown of the matrix, including fibronectin fragments of the degraded matrix which can contribute to further degradation. The involvement of cytokines and other inflammatory mediators in the generation of vascularization and stimulation of pain receptors are still controversial but may reveal the pathway to the symptomatic conditions of IVD degeneration.

The influence of implanted impurities on the thermally-induced epitaxial recrystallization of CoSi₂

Publisher: Springer Science and Business Media LLC

Date: 05-1991

DOI: 10.1557/JMR.1991.1035

Abstract: The influence of implanted impurities (B, O, P, Ar, Xe, Pb, and Bi) on the rate of low-temperature (138 °C), solid-phase epitaxial growth (SPEG) of amorphized CoSi 2 has been studied. SPEG rates of impurity-implanted CoSi 2 , as determined from time-resolved reflectivity measurements, were retarded for all impurities compared to that of Si-implanted CoSi 2 . The extent of retardation varied from a factor of 1.5 for P to 9.4 for Xe. Channeling measurements of impurity-implanted CoSi 2 indicated that Xe and Bi atoms were located on nonsubstitutional lattice sites while ∼40% of Pb atoms occupied either substitutional sites or vacant interstitial cation sites following annealing. The presence of impurities did not affect the CoSi 2 post-anneal crystalline quality, and no significant impurity diffusion was apparent at 138 °C from secondary-ion mass spectrometry measurements.

The association between low virulence organisms in different locations and intervertebral disc structural failure: A meta‐analysis and systematic review

Publisher: Wiley

Date: 16-02-2023

DOI: 10.1002/JSP2.1244

Abstract: Many factors may trigger intervertebral disc (IVD) structural failure (intervertebral disc degeneration (IDD) and endplate changes), including inflammation, infection, dysbiosis, and the downstream effects of chemical factors. Of these, microbial ersity in the IVD and elsewhere in the body has been considered as one of the potential reasons for disc structural failure. The exact relationships between microbial colonization and IVD structural failure are not well understood. This meta‐analysis aimed to investigate the impact of microbial colonization and its location (such as skin, IVD, muscle, soft tissues, and blood) on IVD structural failure and corresponding low back pain (LBP) if any. We searched four online databases for potential studies. The potential relationships between microbial colonization in different s le sources (such as skin, IVD, muscle, soft tissues, and blood) and IDD and endplate change were considered as primary outcomes. Odds ratio (OR) and 95% confidence intervals (CI) for direct comparisons were reported. Grading of Recommendations Assessment, Development and Evaluation (GRADE) scale was used to assess the quality of evidence. Twenty‐five cohort studies met the selection criteria. Overall pooled prevalence of microbial colonization in 2419 patients with LBP was 33.2% (23.6%–43.6%). The pooled prevalence of microbial colonization in 2901 s les was 29.6% (21.0%–38.9%). Compared with the patients without endplate change, the patients with endplate changes had higher rates of microbial colonization of disc (OR = 2.83 95% CI = 1.93–4.14 I 2 = 37.6% p = 0.108). The primary pathogen was Cutibacterium acnes which was present in 22.2% of cases (95% CI = 13.3%–32.5% I 2 = 96.6% p = 0.000). This meta‐analysis and systematic review found low‐quality grade evidence for an association between microbial colonization of disc with endplate changes. The primary pathogen was C. acnes . Due to lack of enough high‐quality studies and methodological limitations of this review, further studies are required to improve our understanding of the potential relationships and mechanisms of microbiota, dysbiosis, IVD colonization and IVD structural failure.

Publication trends in spine research from 2007 to 2016: Comparison of the Orthopaedic Research Society Spine Section and the International Society for the Study of the Lumbar Spine

Publisher: Wiley

Date: 03-2018

DOI: 10.1002/JSP2.1006

Nitric oxide modulates recombinant human bone morphogenetic protein-2-induced corticocancellous autograft incorporation: a study in rat intertransverse fusion

Publisher: Springer Science and Business Media LLC

Date: 09-01-2010

DOI: 10.1007/S00586-009-1263-7

Burnout in orthopaedic surgeons: a review

Publisher: Wiley

Date: 24-06-2013

DOI: 10.1111/ANS.12292

Abstract: Training and practice of orthopaedic surgery are stressful endeavours, placing orthopaedic surgeons at risk of burnout. Burnout syndrome is associated with negative outcomes for patients, institutions and, especially, the surgeon. The aim of this review is to summarize available literature on burnout among orthopaedic surgeons and provide recommendations for future work in this field. A search of MEDLINE (1946-present) and EMBASE (search terms: 'Burnout, Professional' AND 'Orthopaedics' 'Stress, Psychological' AND 'Orthopaedic Surgery' 'Fatigue, Mental' AND 'Orthopaedic Surgery') was performed. The authors focused on articles that assessed burnout among orthopaedic surgeons. All studies used the Maslach Burnout Inventory allowing for cross-study (and cross-country) comparisons. Burnout rates among orthopaedic surgeons are in the range of 50-60%, higher than surgeons in general (range: 30-40% for surgeons in general), with the highest rate (emotional exhaustion and depersonalization scores) among orthopaedic residents, followed by department chairs, followed by faculty members. Both objective factors (caseload, practice setting, etc.) and subjective factors (perception that career was unrewarding, perception of lack of autonomy, etc.) contribute to burnout however, subjective factors show a stronger correlation. Despite the heavy burnout rates among orthopaedic surgeons, little work has been performed in this field. Factors responsible for burnout among various orthopaedic populations should be determined, and appropriate interventions designed to reduce burnout.

The structure and electronic properties of tetrahedrally bonded hydrogenated amorphous carbon

Publisher: AIP Publishing

Date: 05-2023

DOI: 10.1063/5.0147494

Abstract: We have synthesized hydrogenated and deuterated amorphous carbon materials that have a density, 2.7 ± 0.1 g/cm3, consistent with almost entirely tetrahedral bonding. In hydrogen-free tetrahedral amorphous carbon, the presence of a minority of sp2 bonded atoms leads to localized states that could be passivated with hydrogen by analogy with hydrogenated amorphous silicon. Neutron diffraction analysis demonstrated that the local bonding environment is consistent with ab initio models of high density hydrogenated tetrahedral amorphous carbon and with the related tetrahedral molecular structure neopentane. The optical bandgap of our material, 4.5 eV, is close to the bandgap in the density of states determined by scanning tunneling spectroscopy (4.3 eV). This bandgap is considerably larger than that of hydrogen-free tetrahedral amorphous carbon, confirming that passivation of sp2 associated tail-states has occurred. Both the structural and electronic measurements are consistent with a model in which the tetrahedrally bonded carbon regions are terminated by hydrogen, causing hopping conductivity to dominate.

The Biology of Bone Grafting

Publisher: Ovid Technologies (Wolters Kluwer Health)

Date: 2005

DOI: 10.5435/00124635-200501000-00010

Degenerative Cervical Myelopathy: Insights into Its Pathobiology and Molecular Mechanisms

Publisher: MDPI AG

Date: 15-03-2021

DOI: 10.3390/JCM10061214

Abstract: Degenerative cervical myelopathy (DCM), earlier referred to as cervical spondylotic myelopathy (CSM), is the most common and serious neurological disorder in the elderly population caused by chronic progressive compression or irritation of the spinal cord in the neck. The clinical features of DCM include localised neck pain and functional impairment of motor function in the arms, fingers and hands. If left untreated, this can lead to significant and permanent nerve damage including paralysis and death. Despite recent advancements in understanding the DCM pathology, prognosis remains poor and little is known about the molecular mechanisms underlying its pathogenesis. Moreover, there is scant evidence for the best treatment suitable for DCM patients. Decompressive surgery remains the most effective long-term treatment for this pathology, although the decision of when to perform such a procedure remains challenging. Given the fact that the aged population in the world is continuously increasing, DCM is posing a formidable challenge that needs urgent attention. Here, in this comprehensive review, we discuss the current knowledge of DCM pathology, including epidemiology, diagnosis, natural history, pathophysiology, risk factors, molecular features and treatment options. In addition to describing different scoring and classification systems used by clinicians in diagnosing DCM, we also highlight how advanced imaging techniques are being used to study the disease process. Last but not the least, we discuss several molecular underpinnings of DCM aetiology, including the cells involved and the pathways and molecules that are hallmarks of this disease.

Imaging of the relative saturation current density and sheet resistance of laser doped regions via photoluminescence

Publisher: AIP Publishing

Date: 06-08-2013

DOI: 10.1063/1.4817525

Abstract: We present an approach to characterize the relative saturation current density (Joe) and sheet resistance (RSH) of laser doped regions on silicon wafers based on rapid photoluminescence (PL) imaging. In the absence of surface passivation layers, the RSH of laser doped regions using a wide range of laser parameters is found to be inversely proportional to the PL intensity (IPL). We explain the underlying mechanism for this correlation, which reveals that, in principle, IPL is inversely proportional to Joe at any injection level. The validity of this relationship under a wide range of typical experimental conditions is confirmed by numerical simulations. This method allows the optimal laser parameters for achieving low RSH and Joe to be determined from a simple PL image.

In Vivo Measurement of Facet Joint Nitric Oxide in Patients With Chronic Low Back Pain

Publisher: Ovid Technologies (Wolters Kluwer Health)

Date: 06-2007

DOI: 10.1097/BRS.0B013E318067DC97

Plasma processing of PDMS based spinal implants for covalent protein immobilization, cell attachment and spreading

Publisher: Springer Science and Business Media LLC

Date: 30-11-2018

DOI: 10.1007/S10856-018-6181-Y

Abstract: PDMS is widely used for prosthetic device manufacture. Conventional ion implantation is not a suitable treatment to enhance the biocompatibility of poly dimethyl siloxane (PDMS) due to its propensity to generate a brittle silicon oxide surface layer which cracks and delaminates. To overcome this limitation, we have developed new plasma based processes to balance the etching of carbon with implantation of carbon from the plasma source. When this carbon was implanted from the plasma phase it resulted in a surface that was structurally similar and intermixed with the underlying PDMS material and not susceptible to delamination. The enrichment in surface carbon allowed the formation of carbon based radicals that are not present in conventional plasma ion immersion implantation (PIII) treated PDMS. This imparts the PDMS surfaces with covalent protein binding capacity that is not observed on PIII treated PDMS. The change in surface energy preserved the function of bound biomolecules and enhanced the attachment of MG63 osteosarcoma cells compared to the native surface. The attached cells, an osteoblast interaction model, showed increased spreading on the treated over untreated surfaces. The carbon-dependency for these beneficial covalent protein and cell linkage properties was tested by incorporating carbon from a different source. To this end, a second surface was produced where carbon etching was balanced against implantation from a thin carbon-based polymer coating. This had similar protein and cell-binding properties to the surfaces generated with carbon inclusion in the plasma phase, thus highlighting the importance of balancing carbon etching and deposition. Additionally, the two effects of protein linkage and bioactivity could be combined where the cell response was further enhanced by covalently tethering a biomolecule coating, as exemplified here with the cell adhesive protein tropoelastin. Providing a balanced carbon source in the plasma phase is applicable to prosthetic device fabrication as illustrated using a 3-dimensional PDMS balloon prosthesis for spinal implant applications. Consequently, this study lays the groundwork for effective treatments of PDMS to selectively recruit cells to implantable PDMS fabricated biodevices.

Intervertebral disc degeneration and how it leads to low back pain

Publisher: Wiley

Date: 14-11-2023

DOI: 10.1002/JSP2.1231

Abstract: The purpose of this review was to evaluate data generated by animal models of intervertebral disc (IVD) degeneration published in the last decade and show how this has made invaluable contributions to the identification of molecular events occurring in and contributing to pain generation. IVD degeneration and associated spinal pain is a complex multifactorial process, its complexity poses difficulties in the selection of the most appropriate therapeutic target to focus on of many potential candidates in the formulation of strategies to alleviate pain perception and to effect disc repair and regeneration and the prevention of associated neuropathic and nociceptive pain. Nerve ingrowth and increased numbers of nociceptors and mechanoreceptors in the degenerate IVD are mechanically stimulated in the biomechanically incompetent abnormally loaded degenerate IVD leading to increased generation of low back pain. Maintenance of a healthy IVD is, thus, an important preventative measure that warrants further investigation to preclude the generation of low back pain. Recent studies with growth and differentiation factor 6 in IVD puncture and multi‐level IVD degeneration models and a rat xenograft radiculopathy pain model have shown it has considerable potential in the prevention of further deterioration in degenerate IVDs, has regenerative properties that promote recovery of normal IVD architectural functional organization and inhibits the generation of inflammatory mediators that lead to disc degeneration and the generation of low back pain. Human clinical trials are warranted and eagerly anticipated with this compound to assess its efficacy in the treatment of IVD degeneration and the prevention of the generation of low back pain.

Nitric Oxide Modulates Fracture Healing

Publisher: Wiley

Date: 02-2000

DOI: 10.1359/JBMR.2000.15.2.342

Abstract: The role of the messenger molecule nitric oxide has not been evaluated in fracture healing. NO is synthesized by three kinds of nitric oxide synthase (NOS): inducible NOS (iNOS), endothelial (eNOS), and neuronal (bNOS). We evaluated the role of these enzymes in a rat femur fracture-healing model. There was no messenger RNA (mRNA) expression, immunoreactivity, or enzymatic activity for NOS in unfractured femoral cortex. After fracture, however, mRNA, protein, and enzymatic activity for iNOS were identified in the healing rat femoral fracture callus, with maximum activity on day 15. The mRNA expression for eNOS and bNOS was induced slightly later than for iNOS, consistent with a temporal increase in calcium-dependent NOS activity that gradually increased up to day 30. mRNA expression for the three NOS isoforms also was found in six of six human fracture callus s les. To study the effect of suppression of NO synthesis on fracture healing, an experimental group of rats was fed an NOS inhibitor, L-nitroso-arginine methyl ester (L-NAME), and the control group was fed its inactive enantiomer, D-nitroso-arginine methyl ester (D-NAME). An 18% (p < or = 0.01) decrease in cross-sectional area and a 45% (p < or = 0.05) decrease in failure load were observed in the NOS-inhibited group on day 24 after fracture. Furthermore, the effect of NO supplementation to fracture healing was studied by delivering NO to the fracture site using carboxybutyl chitosan NONOate locally. On day 17 after fracture, there was a 30% (p < or = 0.05) increase in cross-sectional area in the NO-donor group compared with the NOS inhibition group. These results show for the first time that NO is expressed during fracture healing in rats and in humans, that suppression of NOS impairs fracture healing, and that supplementation of NO can reverse the inhibition of healing produced by NOS inhibitors.

Fracture healing is modulated by nitric oxide

Publisher: Ovid Technologies (Wolters Kluwer Health)

Date: 02-2000

DOI: 10.1097/00005131-200002000-00032

Effect of rhenium irradiations on the mechanical properties of tungsten for nuclear fusion applications

Publisher: Elsevier BV

Date: 08-2016

DOI: 10.1016/J.JNUCMAT.2016.05.003

Is Stand-Alone Anterior Lumbar Interbody Fusion a Safe and Efficacious Treatment for Isthmic Spondylolisthesis of L5-S1?

Publisher: SAGE Publications

Date: 06-2017

DOI: 10.1177/2192568217699210

Abstract: A systematic review. The objective of this study was to determine the safety and efficacy of stand-alone anterior lumbar interbody fusion (sa-ALIF) for the treatment of symptomatic isthmic spondylolisthesis of L5-S1 by assessing the level of available clinical and radiographic evidence. A systematic review utilizing Medline, Embase, and Scopus online databases was undertaken. Clinical, radiographic, and adverse outcome data were extracted for the relevant isthmic spondylolisthesis cases with the intention of undertaking a meta-analysis. The database search between January 1980 and December 2015 yielded 23 articles that concerned sa-ALIF for isthmic spondylolisthesis of L5-S1. Only in 9 of the 23 articles data could be extracted specific to sa-ALIF for isthmic spondylolisthesis of L5-S1. There was considerable inconsistency in the standards for reporting outcomes of the surgery due to which meta-analysis could not be undertaken, and hence each article was reviewed. There was insufficient evidence to support the safety and efficacy of sa-ALIF for the treatment of isthmic spondylolisthesis of L5-S1. Although sa-ALIF is widely documented in the literature, there was insufficient evidence to support its use in treating this specific pathology. The unique pathological and anatomical situation that isthmic spondylolisthesis of L5-S1 presents must be recognized and its treatment with sa-ALIF should be well thought out.

Estimation of lean body weight in older women with hip fracture

Publisher: Springer Science and Business Media LLC

Date: 04-07-2011

DOI: 10.1007/S12603-011-0100-Y

Abstract: Lean body weight (LBW) decreases with age while total body fat increases, resulting in altered drug pharmacokinetics. A semi-mechanistic equation estimating LBW using height, weight and sex has been developed for potential use across a wide range of body compositions. The aim of this study was to determine the ability of the LBW equation to estimate dual energy x-ray absorptiometry-derived fat free mass (FFM(DXA)) in a population of older women with recent hip fracture. Baseline, four and 12 month data obtained from 23 women enrolled in the Sarcopenia and Hip Fracture study were pooled to give 58 measurements. LBW was estimated using the equation: LBW (kg) = (9270 x Wt) / (8780 + (244 x BMI)). Body composition was classified as: 'normal' (BMI 25kg/m(2) and not sarcopenic), 'sarcopenic' (sarcopenic and BMI 25kg/m(2)). The ability of the LBW equation to predict FFMDXA was determined graphically using Bland-Altman plots and quantitatively using the method of Sheiner and Beal. The mean ± SD age of female participants women was 83±7 years (n=23). Sarcopenia was frequently observed (65.2%). Bland-Altman plots demonstrated an underestimation by the LBW equation compared to FFMDXA. The bias (95% CI) and precision (95% CI) calculated using the method of Sheiner and Beal was 0.5kg (-0.7, 1.66kg) and 4.4kg (-3.7, 12.4kg) respectively for pooled data. This equation can be used to easily calculate LBW. When compared to FFMDXA, the LBW equation resulted in a small underestimation on average in this population of women with recent hip fracture. The degree of bias may not be clinically important although further studies of larger heterogeneous cohorts are needed to investigate and potentially improve the accuracy of this predictive equation in larger clinical cohorts.

Deletion of iNOS gene impairs mouse fracture healing

Publisher: Elsevier BV

Date: 07-2005

DOI: 10.1016/J.BONE.2004.10.002

Abstract: Nitric oxide (NO) is a signaling molecule synthesized from l-arginine by nitric oxide synthases (NOSs). NOS isoforms are either constitutive (endothelial NOS [eNOS] and neuronal NOS [nNOS]) or inducible NOS (iNOS). Previously, our group has reported that NO is expressed during and modulates fracture healing. In this study, we evaluated the specific contribution of iNOS to fracture healing by using iNOS gene therapy in iNOS-deficient mice. Twelve-week-old female wild-type mice and iNOS-KO mice had a right femoral midshaft osteotomy fixed with an intramedullary 0.5-mm-diameter needle. A gelatine sponge was implanted across the fracture site. The gelatine sponge received either Ad5-CMViNOS (in iNOS-deficient mice n=16) or Ad5-CMVempty (in wild-type mice n=15, and iNOS-deficient mice n=15) at a dose of 10(7) pfu. Mice were sacrificed at day 14, and their right and left hind limbs were harvested. Cross-sectional area (CSA) was determined by measuring the callus diameter across the mediolateral and anteroposterior plane using a vernier caliper. Specimens were loaded to failure torsionally in a biaxial INSTRON testing system, and maximum torque, torsional stiffness, and maximal and total energy were determined. Deletion of the iNOS gene decreased the total and maximum energy absorption of the healing femoral fracture by 30% and by 70% (P<0.01), respectively, in comparison to the wild-type mice. This reduction in energy absorption was reversed by iNOScDNA administration via adenovirus vector. Furthermore, iNOScDNA caused an increase in torsional failure by 20% (P=0.01) in comparison to iNOS(-/-) mice that did not receive the iNOScDNA. There were no significant differences in the biomechanical properties of intact femora. These data indicate that iNOS is important in mouse fracture healing. However, the clinical utility of NOS gene therapy to enhance fracture healing will need further evaluation.

Thermal Conductivity of Amorphous NbO_x Thin Films and Its Effect on Volatile Memristive Switching

Publisher: American Chemical Society (ACS)

Date: 29-04-2022

DOI: 10.1021/ACSAMI.2C04618

Abstract: Metal-oxide-metal (MOM) devices based on niobium oxide exhibit threshold switching (or current-controlled negative differential resistance) due to thermally induced conductivity changes produced by Joule heating. A detailed understanding of the device characteristics therefore relies on an understanding of the thermal properties of the niobium oxide film and the MOM device structure. In this study, we use time-domain thermoreflectance to determine the thermal conductivity of amorphous NbO

Nitric Oxide Synthase Isoforms During Fracture Healing

Publisher: Wiley

Date: 03-2001

DOI: 10.1359/JBMR.2001.16.3.535

Abstract: We have shown previously that nitric oxide (NO) has regulatory effects on fracture healing. Our aim here was to investigate the temporal expression patterns of the three NO synthase (NOS) isoforms that are responsible for the generation of NO by semiquantitative competitive polymerase chain reaction (PCR) and immunoblot analysis after femoral fractures in rats. We found that 4 days after fracture, there were increases in the levels of messenger RNA (mRNA) for all three NOS isoforms, with peaks for the inducible NOS (iNOS 35-fold increase, p < 0.05) at day 4, the endothelial NOS (eNOS 5-fold increase, p < 0.05) at day 7, and the neuronal NOS (bNOS 16-fold increase, p < 0.05) at day 21. At a protein level, the time course expression of NOS isoforms was consistent with the results of those at the mRNA level. In addition, we have previously reported a 2.5-fold increase in NOS activity detected by [3H]arginine to [3H]citrulline conversion at day 15 compared with that at day 4 after fracture. The findings that the expression of NOS isoforms during fracture healing is type specific and time dependent are important and may have clinical applications in the regulation of bone repair by NOS inhibitors or stimulators at different stages after injury.

Does soft tissue balancing using intraoperative pressure sensors improve clinical outcomes in total knee arthroplasty? A protocol of a multicentre randomised controlled trial

Publisher: BMJ

Date: 05-2019

DOI: 10.1136/BMJOPEN-2018-027812

Abstract: Soft tissue imbalance is considered to be a major surgical cause of dissatisfaction following total knee arthroplasty (TKA). Surgeon-determined manual assessment of ligament tension has been shown to be a poor determinant of the true knee balance state. The recent introduction of intraoperative sensors, however, allows surgeons to precisely quantify knee compartment pressures and tibiofemoral kinematics, thereby optimising coronal and sagittal plane soft tissue balance. The primary hypothesis of this study is that achieving knee balance with use of sensors in TKA will improve patient-reported outcomes when compared with manual balancing. A multicentred, randomised controlled trial will compare patient-reported outcomes in 222 patients undergoing TKA using sensor-guided balancing versus manual balancing. The sensor will be used in both arms for purposes of data collection however, surgeons will be blinded to the pressure data in patients randomised to manual balancing. The primary outcome will be the change from baseline to 1 year postoperatively in the mean of the four subscales of the Knee Injury and Osteoarthritis Outcome Score (KOOS 4 ) that are most specific to TKA recovery: pain, symptoms, function and knee-related quality of life. Secondary outcomes will include the surgeon’s capacity to determine knee balance, radiographic and functional measures and additional patient-reported outcomes. Normality of data will be assessed, and a Student’s t-test and equivalent non-parametric tests will be used to compare differences in means among the two groups. Ethics approval was obtained from South Eastern Sydney Local Health District, Approval (HREC/18/POWH/320). Results of the trial will be presented at orthopaedic surgical meetings and submitted for publication in a peer-reviewed journal. ACTRN#12618000817246

A Definition of “Flare” in Low Back Pain: A Multiphase Process Involving Perspectives of Individuals With Low Back Pain and Expert Consensus

Publisher: Elsevier BV

Date: 11-2019

DOI: 10.1016/J.JPAIN.2019.03.009

Abstract: Low back pain (LBP) varies over time. Consumers, clinicians, and researchers use various terms to describe LBP fluctuations, such as episodes, recurrences and flares. Although "flare" is use commonly, there is no consensus on how it is defined. This study aimed to obtain consensus for a LBP flare definition using a mixed-method approach. Step 1 involved the derivation of a preliminary candidate flare definition based on thematic analysis of views of 130 consumers in consultation with an expert consumer writer. In step 2, a workshop was conducted to incorporate perspectives of 19 LBP experts into the preliminary flare definition, which resulted in 2 alternative LBP flare definitions. Step 3 refined the definition using a 2-round Delphi consensus with 50 experts in musculoskeletal conditions. The definition favored by experts was further tested with 16 in iduals with LBP in step 4, using the definition in three scenarios. This multiphase study produced a definition of LBP flare that distinguishes it from other LBP fluctuations, represents consumers' views, involves expert consensus, and is understandable by consumers in clinical and research contexts: "A flare-up is a worsening of your condition that lasts from hours to weeks that is difficult to tolerate and generally impacts your usual activities and/or emotions." Perspective: A multiphase process, incorporating consumers' views and expert consensus, produced a definition of LBP flare that distinguishes it from other LBP fluctuations.

The fabrication and properties of silicon-nanocrystal-based devices and structures produced by ion implantation – The search for gain

Publisher: Elsevier BV

Date: 05-2003

DOI: 10.1016/S0168-583X(03)00785-7

Rapid, substrate-independent thickness determination of large area graphene layers

Publisher: AIP Publishing

Date: 05-12-2011

DOI: 10.1063/1.3664633

Abstract: Phase-shifting interferometric imaging is shown to be a powerful analytical tool for studying graphene films, providing quantitative analysis of large area s les with an optical thickness resolution of ≤0.05 nm. The technique is readily able to identify single sheets of graphene and to quantitatively distinguish between layers composed of multiple graphene sheets. The thickness resolution of the technique is shown to result from the phase shift produced by a graphene film as incident and reflected light pass through it, rather than from path-length differences produced by surface height variations. This is enhanced by the high refractive index of graphene, estimated in this work to be nG = 2.99 ± 0.18.

Multiple Lumbar Pedicle Fractures in Osteopetrosis

Publisher: Ovid Technologies (Wolters Kluwer Health)

Date: 04-2010

DOI: 10.1097/BRS.0B013E3181C39082

Demographic, clinical, and operative risk factors associated with postoperative adjacent segment disease in patients undergoing lumbar spine fusions: a systematic review and meta-analysis

Publisher: Elsevier BV

Date: 06-2022

DOI: 10.1016/J.SPINEE.2021.12.002

Abstract: Adjacent segment disease (ASD) is a potential complication following lumbar spinal fusion. This study aimed to demonstrate the demographic, clinical, and operative risk factors associated with ASD development following lumbar fusion. Systematic review and meta-analysis. We identified 35 studies that reported risk factors for ASD, with a total number of 7,374 patients who had lumbar spine fusion. We investigated the demographic, clinical, and operative risk factors for ASD after lumbar fusion. A literature search was done using PubMed, Embase, Medline, Scopus, and the Cochrane library databases from inception to December 2019. The methodological index for non-randomized studies (MINORS) criteria was used to assess the methodological quality of the included studies. A meta-analysis was done to calculate the odds ratio (OR) with the 95% confidence interval (CI) for dichotomous data and mean difference (MD) with 95% CI for continuous data. Thirty-five studies were included in the qualitative analysis, and 22 studies were included in the meta-analyses. The mean quality score based on the MINORS criteria was 12.4±1.9 (range, 8-16) points. Significant risk factors included higher preoperative body mass index (BMI) (mean difference [MD]=1.97 kg/m The overall level of evidence was low to very low. Higher preoperative BMI, floating fusion, superior facet joint violation, and decompression outside fusion construct are significant risk factors of development of ASD following lumbar fusion surgeries.

The fate of transplanted xenogeneic bone marrow-derived stem cells in rat intervertebral discs

Publisher: Wiley

Date: 13-10-2008

DOI: 10.1002/JOR.20567

Abstract: Intervertebral disc degeneration is a major cause and a risk factor for chronic low back pain. The potential of using stem cells to treat disc degeneration has been raised. The aims of our study were to assess whether xenogeneic bone-marrow derived stem cells could survive in a rat disc degeneration model and to determine which cell types, if any, survived and differentiated into disc-like cells. Human bone-marrow derived CD34(+) (hematopoietic progenitor cells) and CD34(-) (nonhematopoietic progenitor cells, including mesenchymal stem cells) cells were isolated, fluorescent-labeled, and injected into rat coccygeal discs. The rats were sacrificed at day 1, 10, 21, and 42. Treated discs were examined by histological and immunostaining techniques and compared to control discs. The survival of transplanted cells was further confirmed with a human nuclear specific marker. Fluorescent labeled CD34(-) cells were detected until day 42 in the nucleus pulposus of the injected discs. After 3 weeks these cells had differentiated into cells expressing chondrocytic phenotype (Collagen II and Sox-9). In contrast, the fluorescent labeled CD34(+) cells could not be detected after day 21. No fluorescence-positive cells were detected in the noninjected control discs. Further, no inflammatory cells infiltrated the nucleus pulposus, even though these animals had not received immunosuppressive treatment. Our data provide evidence that transplanted human BM CD34(-) cells survived and differentiated within the relative immune privileged nucleus pulposus of intervertebral disc degeneration.

Threshold current reduction for the metal–insulator transition in NbO_2−x-selector devices: the effect of ReRAM integration

Publisher: IOP Publishing

Date: 20-03-2015

DOI: 10.1088/0022-3727/48/19/195105

Metal-oxide interface reactions and their effect on integrated resistive/threshold switching in NbO _x

Publisher: IOP Publishing

Date: 19-03-2020

DOI: 10.1088/1361-6528/AB7889

Expression of growth differentiation factor 6 in the human developing fetal spine retreats from vertebral ossifying regions and is restricted to cartilaginous tissues

Publisher: Wiley

Date: 06-08-2015

DOI: 10.1002/JOR.22983

Abstract: During embryogenesis vertebral segmentation is initiated by sclerotomal cell migration and condensation around the notochord, forming anlagen of vertebral bodies and intervertebral discs. The factors that govern the segmentation are not clear. Previous research demonstrated that mutations in growth differentiation factor 6 resulted in congenital vertebral fusion, suggesting this factor plays a role in development of vertebral column. In this study, we detected expression and localization of growth differentiation factor 6 in human fetal spinal column, especially in the period of early ossification of vertebrae and the developing intervertebral discs. The extracellular matrix proteins were also examined. Results showed that high levels of growth differentiation factor 6 were expressed in the nucleus pulposus of intervertebral discs and the hypertrophic chondrocytes adjacent to the ossification centre in vertebral bodies, where strong expression of proteoglycan and collagens was also detected. As fetal age increased, the expression of growth differentiation factor 6 was decreased correspondingly with the progress of ossification in vertebral bodies and restricted to cartilaginous regions. This expression pattern and the genetic link to vertebral fusion suggest that growth differentiation factor 6 may play an important role in suppression of ossification to ensure proper vertebral segmentation during spinal development.

Engineering the Threshold Switching Response of Nb₂O₅-Based Memristors by Ti Doping

Publisher: American Chemical Society (ACS)

Date: 07-01-2021

DOI: 10.1021/ACSAMI.0C19544

Resistive switching behavior in HfO<inf>2</inf> with Nb as an oxygen exchange layer

Publisher: IEEE

Date: 12-2014

DOI: 10.1109/COMMAD.2014.7038714

Finite element modeling of resistive switching in Nb<inf>2</inf>O<inf>5</inf>-based memory device

Publisher: IEEE

Date: 12-2014

DOI: 10.1109/COMMAD.2014.7038711

Finite element modeling of temporal bone graft changes in XLIF: Quantifying biomechanical effects at adjacent levels

Publisher: Wiley

Date: 05-09-2022

DOI: 10.1002/JOR.25166

Abstract: Extreme lateral interbody fusion allows for the insertion of a large‐footprint interbody cage while maintaining the presence of natural stabilizing ligaments and the facets. It is unclear how the load‐distribution mechanisms through these structures alter with temporal changes in the bone graft. The aim of this study was to examine the effects of temporal bone graft changes on load distribution among the cage, graft, and surrounding spinal structures using finite element analysis. Thoracolumbosacral spine computed tomography data from an asymptomatic male subject were segmented into anatomical regions of interest and digitally stitched to generate a surface mesh of the lumbar spine (L1‐S1). The interbody cage was inserted into the L4‐L5 region during surface meshing. A volumetric mesh was generated and imported into finite element software for pre‐processing, running nonlinear static solves, and post‐processing. Temporal stiffening was simulated in the graft region with unbonded (Soft Callus, Temporal Stages 1–3, Solid Graft) and bonded (Partial Fusion, Full Fusion) contact. In flexion and extension, cage stress reduced by 20% from the soft callus to solid graft state. Force on the graft was directly related to its stiffness, and load‐share between the cage and graft improved with increasing graft stiffness, regardless of whether contact was fused with the endplates. Fused contact between the cage‐graft complex and the adjacent endplates shifted load‐distribution pathways from the ligaments and facets to the implant, however, these changes did not extend to adjacent levels. These results suggest that once complete fusion is achieved, the existing load paths are seemingly diminished.

Current concepts in anterior surgery for thoracolumbar trauma

Publisher: Elsevier BV

Date: 04-2002

DOI: 10.1016/S0030-5898(02)00009-3

Abstract: Our goals in writing this article are to facilitate understanding of issues related to (1) why anterior fixation for thoracolumbar fractures are an important tool for managing these injuries, (2) when to perform these as a single procedure, or in combination with other procedures such as vertebrectomy and/or posterior stabilization and fusion, (3) to appreciate the biomechanical and design-related issues of available systems, and (4) what the clinical outcomes are following these procedures.

Is L5–S1 motion segment different from the rest? A radiographic kinematic assessment of 72 patients with chronic low back pain

Publisher: Springer Science and Business Media LLC

Date: 27-11-2017

DOI: 10.1007/S00586-017-5400-4

Abstract: The relationship between biomechanical instability and degenerative changes in the lumbar spine in chronic low back pain (CLBP) patients remains controversial. The main objective of this retrospective radiographical study was to evaluate changes in kinematics at different lumbar levels (in particular the L5-S1 level) with progressive grades of disc degeneration and facet joint osteoarthritis in CLBP patients. Using standing neutral and dynamic flexion/extension (Fx/Ex) radiographs of the lumbar spine, in vivo segmental kinematics at L1-L2 through L5-S1 were evaluated in 72 consecutive CLBP patients. Disc degeneration was quantified using changes in signal intensity and central disc height on mid-sagittal T2-weighted magnetic resonance (MR) scans. Additionally, the presence or absence of facet joint osteoarthritis was noted on T2-weighted axial MR scans. Disc degeneration and facet joint osteoarthritis occurred independent of each other at the L5-S1 level (p = 0.188), but an association was observed between the two at L4-L5 (p < 0.001) and L3-L4 (p < 0.05) levels. In the absence of facet joint osteoarthritis, the L5-S1 segment showed a greater range of motion (ROM) in Ex (3.3° ± 3.6°) and a smaller ROM in Fx (0.6° ± 4.2°) compared with the upper lumbar levels (p < 0.05), but the differences diminished in the presence of it. In the absence of facet joint osteoarthritis, no change in L5-S1 kinematics was observed with progressive disc degeneration, but in its presence, restabilisation of the L5-S1 segment was observed between mild and severe disc degeneration states. The L5-S1 motion segment exhibited unique degenerative and kinematic characteristics compared with the upper lumbar motion segments. Disc degeneration and facet joint osteoarthritis occurred independent of each other at the L5-S1 level, but not at the other lumbar levels. Severe disc degeneration in the presence of facet joint osteoarthritis biomechanically restabilised the L5-S1 motion segment.

Clinicians’ perceptions around discectomy surgery for lumbar disc herniation: a survey of orthopaedic and neuro-surgeons in Australia and New Zealand

Publisher: Springer Science and Business Media LLC

Date: 03-07-2021

DOI: 10.1007/S00402-021-04019-3

Oxygen diffusion in TiO 2 films studied by electron and ion Rutherford backscattering

Publisher: Elsevier BV

Date: 05-2017

DOI: 10.1016/J.TSF.2017.03.024

Bone morphogenetic protein-7 protects human intervertebral disc cells in vitro from apoptosis

Publisher: Elsevier BV

Date: 05-2008

DOI: 10.1016/J.SPINEE.2007.04.021

Abstract: Disc degeneration includes dysfunction and loss of disc cells leading to a decrease in extracellular matrix (ECM) components. Apoptosis has been identified in degenerated discs. Bone morphogenetic protein-7 (BMP-7) has been reported to stimulate ECM synthesis in the intervertebral disc (IVD), but its effect on disc cell viability is unknown. To investigate whether BMP-7 can protect disc cells from programmed cell death while enhancing ECM production. An in vitro study to examine the effect of BMP-7 on apoptosis of IVD cells. Human nucleus pulposus (NP) cells were cultured in monolayer, and human recombinant pure BMP-7 (rhBMP-7) was added to the medium when the cells were in the second passage. Thereafter, apoptosis was induced by either tumor necrosis factor-alpha (TNF-alpha) or hydrogen peroxide (H(2)O(2)). Cellular apoptosis was evaluated by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling assay and caspase-3 activity. ECM synthesis was assessed by immunofluorescence for collagen-2 and aggrecan. To study the possibility of bone induction by rhBMP-7 in disc cells, alkaline phosphatase activity and Alizarin red-S staining were evaluated. Apoptosis was induced by both TNF-alpha and H(2)O(2). Addition of rhBMP-7 resulted in inhibition of the apoptotic effects caused by both inducers. Further, BMP-7 decreased caspase-3 activity. In the presence of BMP-7, ECM production was maintained by the cells despite being in an apoptotic environment. No osteoblastic induction of the disc cells was seen. BMP-7 was demonstrated to prevent apoptosis of human disc cells in vitro. One of the antiapoptotic effects of BMP-7 on NP cells might be a result of its inactivation of caspase-3. Collagen production was maintained by addition of rhBMP-7 in an apoptotic environment.

Temperature dependence of threshold switching in NbO<inf>x</inf> thin films

Publisher: IEEE

Date: 12-2014

DOI: 10.1109/COMMAD.2014.7038673

Primum non nocere and randomised placebo‐controlled surgical trials: a dilemma?

Publisher: Wiley

Date: 07-2009

DOI: 10.1111/J.1445-2197.2009.04975.X

Osteoporosis influences the early period of fracture healing in a rat osteoporotic model

Publisher: Elsevier BV

Date: 2001

DOI: 10.1016/S8756-3282(00)00414-2

Abstract: Osteoporotic fractures commonly occur in the elderly. Although current therapies are aimed at the prevention and treatment of osteoporotic fractures, studies examing the fracture healing process in osteoporotic bone are limited. We produced an osteoporotic rat model by ovariectomy (ovx) and maintained a low calcium diet (LCD) in order to evaluate the influence of osteoporosis on fracture healing. Callus formation and strength was monitored over a 3 week period by histological and biomechanical assessment. Data collected simultaneously on a group of rats undergoing sham surgery (sx) were used for comparison. A 40% reduction in fracture callus cross-sectional area and a 23% reduction in bone mineral density in the healing femur of the ovx rats was observed on day 21 following fracture as compared with the sx group (p < 0.01). Biomechanical data from the healing femur of the ovx rats revealed a fivefold decrease in the energy required to break the fracture callus, a threefold decrease in peak failure load, a twofold decrease in stiffness and a threefold decrease in stress as compared with the sx group (p < 0.01, respectively). Histomorphological analysis revealed a delay in fracture callus healing with poor development of mature bone in the ovx rats. This study provides physical evidence of altered fracture healing in osteoporotic bone, which may have important implications in evaluating the effects of new treatments for osteoporosis on fracture healing.

Self-assembly of an NbO2 interlayer and configurable resistive switching in Pt/Nb/HfO2/Pt structures

Publisher: AIP Publishing

Date: 28-09-2015

DOI: 10.1063/1.4932096

Abstract: A configurable resistive switching response is reported for Pt/Nb/HfO2/Pt devices subjected to different set compliance currents. When operated at a low compliance-current (∼100 μA), devices show uniform bipolar resistive switching behavior. As the compliance current is increased (∼500 μA), the switching mode changes to integrated threshold-resistive (1S1M) switching, and at still higher currents (∼1 mA), it changes to symmetric threshold switching (1S) characteristic of threshold switching in NbO2−δ. These switching transitions are shown to be consistent with the development of an NbO2−δ interlayer at the Nb/HfO2 interface that is limited by the set compliance current due to its effect on oxygen transport and local Joule heating. The proposed mechanism is supported by finite element modeling of the 1S1M response assuming the presence of such an interlayer. These findings help to understand role of interface reactions in controlling device performance and provide a means for the self-assembly of integrated 1S1M resistive random access memory structures.

Hyaluronan: its potential application in intervertebral disc regeneration

Publisher: Informa UK Limited

Date: 03-2010

DOI: 10.2147/ORR.S7741

Prevalence and Factors of Burnout among Australian Orthopaedic Trainees: A Cross-Sectional Study

Publisher: SAGE Publications

Date: 12-2014

DOI: 10.1177/230949901402200322

Abstract: To assess the prevalence and factors of burnout among Australian orthopaedic trainees. 236 orthopaedic registrars of the Australian Orthopaedic Association were invited to participate in a 32-item survey by email. The questionnaire assessed potential factors associated with burnout, satisfaction with the choice of orthopaedics as a career and work-life balance, and subjective overall health, as well as 3 subscales of the Maslach Burnout Inventory – Human Services Survey for assessing burnout: emotional exhaustion, depersonalisation, and personal accomplishment. Participants with high levels of either emotional exhaustion or depersonalisation were defined as having burnout. Those with and without burnout were compared. 51 (22%) of the 236 trainees completed the questionnaire. Of whom, 88% were satisfied with their choice of orthopaedics as a career, whereas 27% were satisfied with their work-life balance. 27 (53%) respondents were considered burned out. Compared with those who did not burn out, those who burned out were less satisfied with their careers (p=0.004) and work-life balance (p=0.021). 53% of Australian orthopaedic trainees were burned out. Burnout trainees were more likely to be dissatisfied with their career choice and work-life balance. Active interventions to combat burnout and improve work-life balance are needed.

Effect of W self-implantation and He plasma exposure on early-stage defect and bubble formation in tungsten

Publisher: IOP Publishing

Date: 18-04-2018

DOI: 10.1088/1741-4326/AAB96C

Using doping superlattices to study transient-enhanced diffusion of boron in regrown silicon

Publisher: AIP Publishing

Date: 27-05-1996

DOI: 10.1063/1.116439

Abstract: A boron-doped silicon superlattice consisting of three boron spikes separated by 1700 Å of undoped silicon has been grown by molecular beam epitaxy and used to study the evolution of point defects following an amorphizing implant of Si+. After MBE growth, the wafer was implanted at 77 K with either 146 or 292 keV Si+ at a dose of 5×1015/cm2. These implants produced amorphous layer depths that coincided with the depths of either the middle B peak or just below the deepest B peak. The s les were then annealed at 800 °C in an Ar ambient. Secondary-ion-mass spectrometry and transmission electron microscopy were used to monitor the diffusion of the boron spikes upon annealing and the evolution of the extended defects upon annealing, respectively. For the lower-energy s le, an enhancement in the B diffusivity of over 500× was observed for both the surface B spike and the deepest B spike. The higher-energy implant shows conclusively that the back flow of interstitials into the regrown region is coming from the end-of-range damage just below the amorphous/crystalline interface. These results show that for these implant conditions the end-of-range damage does not act as a barrier to flow of interstitials to the surface. In addition it is noted that boron in the regrown silicon does not cluster whereas the boron below the amorphous crystalline interface does. Both of these features must be accounted for when modeling boron diffusion in regrown silicon.

Physical and optical characterisation of Ge-implanted silica

Publisher: Elsevier BV

Date: 04-2001

DOI: 10.1016/S0168-583X(00)00536-X

The role of BMP-7 in chondrogenic and osteogenic differentiation of human bone marrow multipotent mesenchymal stromal cells in vitro

Publisher: Wiley

Date: 2009

DOI: 10.1002/JCB.22412

Abstract: This study addresses the role of bone morphogenetic protein-7 (BMP-7) in chondrogenic and osteogenic differentiation of human bone marrow multipotent mesenchymal stromal cells (BM MSCs) in vitro. BM MSCs were expanded and differentiated in the presence or absence of BMP-7 in monolayer and three-dimensional cultures. After 3 days of stimulation, BMP-7 significantly inhibited MSC growth in expansion cultures. When supplemented in commonly used induction media for 7-21 days, BMP-7 facilitated both chondrogenic and osteogenic differentiation of MSCs. This was evident by specific gene and protein expression analyses using real-time PCR, Western blot, histological, and immunohistochemical staining. BMP-7 supplementation appeared to enhance upregulation of lineage-specific markers, such as type II and type IX collagens (COL2A1, COL9A1) in chondrogenic and secreted phosphoprotein 1 (SPP1), osteocalcin (BGLAP), and osterix (SP7) in osteogenic differentiation. BMP-7 in the presence of TGF-beta3 induced superior chondrocytic proteoglycan accumulation, type II collagen, and SOX9 protein expression in alginate and pellet cultures compared to either factor alone. BMP-7 increased alkaline phosphatase activity and dose-dependently accelerated calcium mineralization of osteogenic differentiated MSCs. The potential of BMP-7 to promote adipogenesis of MSCs was restricted under osteogenic conditions, despite upregulation of adipocyte gene expression. These data suggest that BMP-7 is not a singular lineage determinant, rather it promotes both chondrogenic and osteogenic differentiation of MSCs by co-ordinating with initial lineage-specific signals to accelerate cell fate determination. BMP-7 may be a useful enhancer of in vitro differentiation of BM MSCs for cell-based tissue repair.

Fusion Versus Disk Replacement for Degenerative Conditions of the Lumbar and Cervical Spine: Quid Est Testimonium?

Publisher: Elsevier BV

Date: 04-2010

DOI: 10.1016/J.OCL.2009.12.002

Abstract: This article compares the outcomes following spinal fusion and disk replacement for degenerative conditions of the lumbar and cervical spine. The short-term outcomes of lumbar and cervical total disk replacement are equivalent to that following spinal fusion. Long-term follow-up studies of total disk replacement are necessary to confirm its potential benefit in reducing or preventing adjacent level degeneration. Also discussed is the philosophy of the surgical management of degenerative conditions of the lumbar and cervical spine.

Origin of Current‐Controlled Negative Differential Resistance Modes and the Emergence of Composite Characteristics with High Complexity

Publisher: Wiley

Date: 28-08-2019

DOI: 10.1002/ADFM.201905060

Temperature trends in total hip arthroplasty

Publisher: Elsevier BV

Date: 06-2003

DOI: 10.1016/S0883-5403(03)00015-9

Abstract: The purpose of this study was to define the temporal trend in body temperature of patients during the first 5 days after total hip arthroplasty (THA). The medical records of 98 consecutive THAs were reviewed, 88 clinically uncomplicated cases were included. The average maximum temperature reached during the study period was 38.08 degrees C, a 3.7% (P or =38.0 degrees C 19.3% > or = 38.5 degrees C and 3.4% > or = 39.0 degrees C. No patients had a preoperative temperature of > or =38 degrees C recorded. On the first postoperative day, 39 patients had a temperature > or =38 degrees C. The number of febrile patients progressively decreased until by the fifth postoperative day, only 5 patients had a temperature > or =38 degrees C recorded.

High performance bulk photovoltaics in narrow-bandgap centrosymmetric ultrathin films

Publisher: Royal Society of Chemistry (RSC)

Date: 2020

DOI: 10.1039/C9MH01744E

Abstract: Intensive bulk photovoltaic effects are produced in narrow-bandgap centrosymmetric materials by a new strategy based on polar nano-regions.

Oxygen Self-Diffusion inHfO2

Publisher: American Physical Society (APS)

Date: 30-04-2014

DOI: 10.1103/PHYSREVLETT.112.175901

Correction to: ISSLS PRIZE IN BASIC SCIENCE 2018: Growth differentiation factor-6 attenuated pro-inflammatory molecular changes in the rabbit anular-puncture model and degenerated disc-induced pain ge

Publisher: Springer Science and Business Media LLC

Date: 19-01-2019

DOI: 10.1007/S00586-019-05878-6

Abstract: The author "Ashish D. Diwan" receives educational consultant fees from Nuvasive Inc.

Mechanical properties of tungsten following rhenium ion and helium plasma exposure

Publisher: Elsevier BV

Date: 08-2017

DOI: 10.1016/J.NME.2017.04.012

The Role of Sacral Slope in the Progression of a Bilateral Spondylolytic Defect at L5 to Spondylolisthesis: A Biomechanical Investigation Using Finite Element Analysis

Publisher: SAGE Publications

Date: 16-11-2018

DOI: 10.1177/2192568217735802

Global and segmental kinematic changes following sequential resection of posterior osteoligamentous structures in the lumbar spine: An in vitro biomechanical investigation using pure moment testing pr

Publisher: SAGE Publications

Date: 25-10-2015

DOI: 10.1177/0954411915612503

Abstract: Lumbar spinal surgeries may compromise the integrity of posterior osteoligamentous structures implicating mechanical stability. Circumstances necessitating a concomitant surgery to achieve restabilisation are not well understood. The main objective of this in vitro study was to quantify global and segmental (index and adjacent levels) kinematic changes in the lumbar spine following sequential resection of the posterior osteoligamentous structures using pure moment testing protocols. Six fresh frozen cadaveric kangaroo lumbar spines (T12–S1) were tested under a bending moment in flexion–extension, bilateral bending, and axial torsion in a 6-degree-of-freedom Kinematic Spine Simulator. Specimens were tested in the following order: intact state (D 0 ), after interspinous and supraspinous ligaments transection between L4 and L5 (D 1 ), further after a total bilateral facetectomy between L4 and L5 (D 2 ). Segmental motions at the cephalad, damaged, and caudal levels were recorded using an infrared-based motion tracking device. Following D 1 , no significant change in the global range of motion was observed in any of the bending planes. Following D 2 , a significant increase in the global range of motion from the baseline (D 0 ) was observed in axial torsion (median normalised change +20%). At the damaged level, D 2 resulted in a significant increase in the segmental range of motion in flexion–extension (+77%) and axial torsion (+492%). Additionally, a significant decrease in the segmental range of motion in axial torsion (−35%) was observed at the caudal level following D 2 . These results suggest that a multi-segment lumbar spine acts as a mechanism for transmitting motions, and that a compromised joint may significantly alter motion transfer to adjacent segments. We conclude that the interspinous and supraspinous ligaments play a modest role in restricting global spinal motions within physiologic limits. Following interspinous and supraspinous ligaments transection, a total bilateral facetectomy resulted in a significant increase in axial torsion motion, both at global and damaged levels, accompanied with a compensatory decrease in motion at the caudal level.

Temporal expression of nitric oxide synthase isoforms in healing Achilles tendon

Publisher: Wiley

Date: 2001

DOI: 10.1016/S0736-0266(00)00019-X

An Interlocking Ligamentous Spinal Disk Arthroplasty with Neural Network Infrastructure

Publisher: Trans Tech Publications, Ltd.

Date: 10-2010

DOI: 10.4028/WWW.SCIENTIFIC.NET/JBBTE.7.55

Abstract: An elastomeric spinal disk prosthesis design (BioFI™) with vertebral interlocking anchors has been modified using an embedded TiNi wire array. Bioinert styrenic block copolymer (Kraton®) and polycarbonate urethane (Bionate®) thermoplastic elastomer (TPE) matrices were utilized. Fatigue resistant NiTi wire was pretreated to induce superelastic martensitic microstructure. Stent-like helical structures were produced for incorporation within homogenous TPE matrix. Composite prototypes were fabricated in a vacuum hot press using transfer moulding techniques. Implant prototypes were subject to axial compression using a BOSE ® ELF3400. The NiTi reinforced implants exhibited reduction in axial strain, compliance, and creep compared to TPE controls. The axial properties of the NiTi reinforced Bionate® BioFI™ implant best approximated those of a spinal disk followed by Kraton®-NiTi, Bionate® and Kraton® prototypes. An ovine lumbar segment biomechanical model was used to characterize the disk prosthesis prototypes. Specimens were subject to 7.5Nm pure moments in axial rotation, flexion-extension and lateral bending with a custom jig mounted on an Instron® 8874. The motion preserving ligamentous nature of this arthroplasty prototype was not inhibited by NiTi reinforcement. Joint stiffness for all prototypes was significantly less than the intact and discectomy controls. This was due to lack of vertebral anchor rigidity rather than BioFI™ motion segment matrix type or reinforcement. Implant stress profiles for axial compression and axial torsion conditions were obtained using finite element methods. The biomechanical testing and finite element modelling both support existing BioFI™ design specifications for higher modulus vertebral anchors, endplates and motion segment periphery with gradation to a low modulus core within the motion segment. This closer approximation of the native spinal disk form translates to improvements in prosthesis biomechanical fidelity and longevity. Axial compressive strain induced within a TiNi reinforced Kraton® BioFI™ was found to be linearly proportional to the NiTi helical coil electrical resistance. This neural network capability delivers opportunities to monitor and telemeterize in situ multiaxis joint structural performance and in vivo spine biomechanics.

Determination of thickness and composition of high-k dielectrics using high-energy electrons

Publisher: AIP Publishing

Date: 12-08-2013

DOI: 10.1063/1.4818637

Abstract: We demonstrate the application of high-energy elastic electron backscattering to the analysis of thin (2–20 nm) HfO2 overlayers on oxidized Si substrates. The film composition and thickness are determined directly from elastic scattering peaks characteristic of each element. The stoichiometry of the films is determined with an accuracy of 5%–10%. The experimental results are corroborated by medium energy ions scattering and Rutherford backscattering spectrometry measurements, and clearly demonstrate the applicability of the technique for thin-film analysis. Significantly, the presented technique opens new possibilities for nm depth profiling with high spatial resolution in scanning electron microscopes.

Retroperitoneal lymphocele after lumbar total disc replacement: a case report and review of literature

Publisher: International Journal of Spine Surgery

Date: 09-2010

DOI: 10.1016/J.ESAS.2010.01.006

Isotopically Enriched10BN Nanotubes

Publisher: Wiley

Date: 18-08-2006

DOI: 10.1002/ADMA.200600231

Changes in Back Pain Scores after Bariatric Surgery in Obese Patients: A Systematic Review and Meta-Analysis

Publisher: MDPI AG

Date: 04-2021

DOI: 10.3390/JCM10071443

Abstract: Bariatric surgery produces significant and quantifiable reductions in back pain. However, there is a lack of information on the association of weight changes after bariatric surgery with changes in pain score. We aim to evaluate the impact of bariatric surgery on back pain in obese patients and to address the association between changes in body mass index (BMI) and pain score. In obese patients eligible for bariatric surgery, the changes in pre- and post-operative pain scores, assessed by the Numeric Rating Pain Scale (NPS) or Visual Analogue Scale (VAS), were considered as primary outcomes. Mean difference (MD) and their 95% confidence intervals (CI) were evaluated. Eight cohort studies were included in the analysis of 298 obese patients undergoing bariatric surgery. All studies showed a reduction in back pain, with a mean change of −2.9 points in NPS and of −3.8 cm in VAS. There was a significant reduction in back pain (NPS: (MD = −3.49) (95% CI = −3.86, −3.12) VAS: MD = −3.75, (95% CI = −4.13, −3.37)) and BMI (MD = −12.93, (95% CI = −13.61, −12.24)) following bariatric surgery. No significant relationship between BMI change and decrease in clinical scores could be established. However, it was evident that bariatric surgery had a significant effect on back pain scores in severely obese patients. Ideally, a prospective study including spinal imaging, inflammatory markers, a longer follow-up period, and larger study groups with a randomized control group needs to be performed.

Chronic low back pain: issues and management, part II

Publisher: Elsevier BV

Date: 2004

DOI: 10.1016/S0030-5898(03)00107-X

Recurrent and Injurious Falls in the Year Following Hip Fracture: A Prospective Study of Incidence and Risk Factors From the Sarcopenia and Hip Fracture Study

Publisher: Oxford University Press (OUP)

Date: 05-03-2009

DOI: 10.1093/GERONA/GLP003

Abstract: The incidence and etiology of falls in patients following hip fracture remains poorly understood. We prospectively investigated the incidence of, and risk factors for, recurrent and injurious falls in community-dwelling persons admitted for surgical repair of minimal-trauma hip fracture. Fall surveillance methods included phone calls, medical records, and fall calendars. Potential predictors of falls included health status, quality of life, nutritional status, body composition, muscle strength, range of motion, gait velocity, balance, walking endurance, disability, cognition, depression, fear of falling, self-efficacy, social support, physical activity level, and vision. 193 participants enrolled in the study (81 +/- 8 years, 72% women, gait velocity 0.3 +/- 0.2 m/s). We identified 227 falls in the year after hip fracture for the 178 participants with fall surveillance data. Fifty-six percent of participants fell at least once, 28% had recurrent falls, 30% were injured, 12% sustained a new fracture, and 5% sustained a new hip fracture. Age-adjusted risk factors for recurrent and injurious falls included lower strength, balance, range of motion, physical activity level, quality of life, depth perception, vitamin D, and nutritional status, and greater polypharmacy, comorbidity, and disability. Multivariate analyses identified older age, congestive heart failure, poorer quality of life, and nutritional status as independent risk factors for recurrent and injurious falls. Recurrent and injurious falls are common after hip fracture and are associated with multiple risk factors, many of which are treatable. Interventions should therefore be tailored to alleviating or reversing any nutritional, physiological, and psychosocial risk factors of in idual patients.

Australian medical students and their choice of surgery as a career: a review

Publisher: Wiley

Date: 16-09-2013

DOI: 10.1111/ANS.12389

Abstract: Surgery is an emotionally, physically and mentally challenging profession, and medical students factor in many variables when choosing surgery as a career choice. The aim of this study is to review the available literature on the factors influencing Australian medical students' choice of surgery as their career. A search of EMBASE and MEDLINE with the search terms 'medical students' AND 'surgery' 'medical students' AND 'career pathways' 'medical students' AND 'career choices' was conducted. Additionally, Google Scholar and the reference list of some articles were canvassed for suitable areas of study. Lifestyle factors were the main reason influencing medical student's career choices. A balance between work, family and lifestyle was found to be important, and a surgical career choice was not always compatible with this. In particular, female students placed more importance on family and lifestyle factors when opting for non-surgical careers. Positive exposure and/or experiences in a surgical environment, perceived prestige and perceived financial reward were associated with surgical career choice. There is a need to better understand the factors influencing surgical and non-surgical career choice among Australian medical students, and develop appropriate interventions to promote surgery as a career. This article does not discuss personality traits of people who go into surgery.

Physical Origin of Negative Differential Resistance in V₃O₅ and Its Application as a Solid‐State Oscillator

Publisher: Wiley

Date: 30-12-2022

DOI: 10.1002/ADMA.202208477

Abstract: Oxides that exhibit an insulator–metal transition can be used to fabricate energy‐efficient relaxation oscillators for use in hardware‐based neural networks but there are very few oxides with transition temperatures above room temperature. Here the structural, electrical, and thermal properties of V 3 O 5 thin films and their application as the functional oxide in metal/oxide/metal relaxation oscillators are reported. The V 3 O 5 devices show electroforming‐free volatile threshold switching and negative differential resistance (NDR) with stable ( % variation) cycle‐to‐cycle operation. The physical mechanisms underpinning these characteristics are investigated using a combination of electrical measurements, in situ thermal imaging, and device modeling. This shows that conduction is confined to a narrow filamentary path due to self‐confinement of the current distribution and that the NDR response is initiated at temperatures well below the insulator–metal transition temperature where it is dominated by the temperature‐dependent conductivity of the insulating phase. Finally, the dynamics of in idual and coupled V 3 O 5 ‐based relaxation oscillators is reported, showing that capacitively coupled devices exhibit rich non‐linear dynamics, including frequency and phase synchronization. These results establish V 3 O 5 as a new functional material for volatile threshold switching and advance the development of robust solid‐state neurons for neuromorphic computing.

CURRENT CONCEPTS IN INTERVERTEBRAL DISK RESTORATION

Publisher: Elsevier BV

Date: 07-2000

DOI: 10.1016/S0030-5898(05)70163-2

Abstract: A current focus of treatment for degenerative disk disease is the restoration of the intervertebral disk. This article summarizes the structure and function of the intervertebral disk, the pathogenesis of its degeneration, and the clinical relevance of degenerative disk disease. Current literature relating to intervertebral disk replacement and regeneration is reviewed.

Boron implanted, laser annealed p+ emitter for n-type interdigitated back-contact solar cells

Publisher: Elsevier BV

Date: 2014

DOI: 10.1016/J.EGYPRO.2014.08.093

Methodology and Baseline Characteristics for the Sarcopenia and Hip Fracture Study: A 5-Year Prospective Study

Publisher: Oxford University Press (OUP)

Date: 19-02-2009

DOI: 10.1093/GERONA/GLP002

Abstract: Age-related hip fractures are associated with poor functional outcomes, resulting in substantial personal and societal burden. There is a need to better identify reversible etiologic predictors of suboptimal functional recovery in this group. The Sarcopenia and Hip Fracture (SHIP) study was a 5-year prospective cohort study following community-dwelling older persons admitted to three Sydney hospitals for hip fracture. Information was collected at baseline, and 4 and 12 months, including health status, quality of life, nutritional status, body composition, muscle strength, range of motion, gait velocity, balance, walking endurance, disability, cognition, depression, fear of falling, self-efficacy, social support, physical activity level, vision, and fall-related data, with residential status, disability, and mortality reassessed at 5 years. 193 participants enrolled (81 +/- 8 years, 72% women). High levels of activities of daily living, disability and sedentariness were present prior to fracture. At admission, the cohort had high levels of chronic disease 38% were depressed, 38% were cognitively impaired, and 26% had heart disease. Seventy-one percent of participants were sarcopenic, 58% undernourished, and 55% vitamin D deficient. Mobility, strength, and vision were severely impaired. There was little evidence that these comorbidities were either recognized or treated during hospitalization. Disability, sedentariness, malnutrition, and walking endurance predicted acute hospitalization length of stay. The complex comorbidity, pre-existing functional impairment, and sedentary behavior in patients with hip fracture suggest the need for thorough screening and targeting of potentially reversible impairments. Rehabilitation outcomes are likely to be highly dependent on amelioration of these highly prevalent accompaniments to hip fracture.

The composition, structure and properties of four different glassy carbons

Publisher: Elsevier BV

Date: 10-2019

DOI: 10.1016/J.JNONCRYSOL.2019.119561

Single-Cell Transcriptome Profiling Reveals Multicellular Ecosystem of Nucleus Pulposus during Degeneration Progression.

Publisher: Wiley

Date: 26-11-2021

DOI: 10.1002/ADVS.202103631

Abstract: Although degeneration of the nucleus pulposus (NP) is a major contributor to intervertebral disc degeneration (IVDD) and low back pain, the underlying molecular complexity and cellular heterogeneity remain poorly understood. Here, a comprehensive single‐cell resolution transcript landscape of human NP is reported. Six novel human NP cells (NPCs) populations are identified by their distinct molecular signatures. The potential functional differences among NPC subpopulations are analyzed. Predictive transcripts, transcriptional factors, and signal pathways with respect to degeneration grades are explored. It is reported that fibroNPCs is the subpopulation for end‐stage degeneration. CD90+NPCs are observed to be progenitor cells in degenerative NP tissues. NP‐infiltrating immune cells comprise a previously unrecognized ersity of cell types, including granulocytic myeloid‐derived suppressor cells (G‐MDSCs). Integrin α M (CD11b) and oxidized low density lipoprotein receptor 1 (OLR1) as surface markers of NP‐derived G‐MDSCs are uncovered. The G‐MDSCs are found to be enriched in mildly degenerated (grade II and III) NP tissues compared to severely degenerated (grade IV and V) NP tissues. Their immunosuppressive function and alleviation effects on NPCs’ matrix degradation are revealed in vitro. Collectively, this study reveals the NPC‐type complexity and phenotypic characteristics in NP, thereby providing new insights and clues for IVDD treatment.

Poor histological healing of a femoral fracture following 12 months of oestrogen deficiency in rats

Publisher: Springer Science and Business Media LLC

Date: 06-04-2013

DOI: 10.1007/S00198-013-2345-2

Abstract: Fractures in post-menopausal osteoporosis cause significant morbidity however, animal models for post-menopausal fracture healing lack the effect of ageing. Therefore, we developed a model using aged animals with chronic oestrogen deficiency, which demonstrates inferior fracture repair (decreased healing histologically, bone mineral density and content and strength). This novel model may help develop molecular strategies for osteoporotic fracture repair. The femur is susceptible to damage by both systemic conditions such as osteoporosis and locally by traumatic injury. The capacity for fracture repair decreases with age, while the risk of fracture increases. As studies of osteoporotic fracture healing in rats traditionally use a period of 3 months or less of oestrogen deficiency prior to fracturing, we aimed to establish a osteoporosis model in rats with chronic oestrogen deficiency by 12 months to better mimic human female osteoporosis. Seventy female Sprague-Dawley rats (10 weeks old) were ovariectomised or sham operated and housed for 12 months. The right femur was fractured by way of an open osteotomy and fixed with an intramedullary Kirschner wire. Animals were sacrificed at 1, 3 and 6 weeks for radiography, dual-energy X-ray absorptiometry, tensile testing and histology. Bone mineral density and bone mineral content were lower by 60 and 63 %, respectively, (p < 0.05) in the bilaterally ovariectomized (OVX) groups than those in the sham groups at 6 weeks in the right fractured femurs. Maximum breaking force of the OVX group was lower than that of the sham group, with the greatest difference seen at 6 weeks following osteotomy. Histologically, the OVX groups demonstrated a delay in cellular differentiation within the fracture callus and the presence of bone resorption. The sham animals had a superior histological healing pattern with an Allen score of 4 at 6 weeks compared to a score of 1 for the OVX groups (p < 0.01). Long-term ovariectomy has a deleterious effect on fracture healing in a rodent model.

Reduced Threshold Current in NbO₂ Selector by Engineering Device Structure

Publisher: Institute of Electrical and Electronics Engineers (IEEE)

Date: 10-2014

DOI: 10.1109/LED.2014.2344105

Blood-Spinal Cord Barrier: Its Role in Spinal Disorders and Emerging Therapeutic Strategies

Publisher: MDPI AG

Date: 21-12-2021

DOI: 10.3390/NEUROSCI3010001

Abstract: The blood-spinal cord barrier (BSCB) has been long thought of as a functional equivalent to the blood-brain barrier (BBB), restricting blood flow into the spinal cord. The spinal cord is supported by various disc tissues that provide agility and has different local immune responses compared to the brain. Though physiologically, structural components of the BSCB and BBB share many similarities, the clinical landscape significantly differs. Thus, it is crucial to understand the composition of BSCB and also to establish the cause–effect relationship with aberrations and spinal cord dysfunctions. Here, we provide a descriptive analysis of the anatomy, current techniques to assess the impairment of BSCB, associated risk factors and impact of spinal disorders such as spinal cord injury (SCI), amyotrophic lateral sclerosis (ALS), peripheral nerve injury (PNI), ischemia reperfusion injury (IRI), degenerative cervical myelopathy (DCM), multiple sclerosis (MS), spinal cavernous malformations (SCM) and cancer on BSCB dysfunction. Along with diagnostic and mechanistic analyses, we also provide an up-to-date account of available therapeutic options for BSCB repair. We emphasize the need to address BSCB as an in idual entity and direct future research towards it.

Smoking and tetramer tryptase accelerate intervertebral disc degeneration by inducing METTL14-mediated DIXDC1 m⁶ modification.

Publisher: Elsevier BV

Date: 08-2023

DOI: 10.1016/J.YMTHE.2023.06.010

MeV implantation into semiconductors

Publisher: Elsevier BV

Date: 06-1993

DOI: 10.1016/0168-583X(93)96170-H

Age-based exclusion is common and multifactorial in spinal RCTs: a systematic review and quantitative analysis

Publisher: Springer Science and Business Media LLC

Date: 07-03-2023

DOI: 10.1007/S00586-023-07618-3

Abstract: Most diseases of the spine disproportionately impact older persons, with the modal (i.e., commonest) patient a female in their 8th decade of life. We examined the corpus of spinal RCTs to determine how many included “average” spine patients. We searched PubMed for randomized clinical trials published in the top 7 spine journals over a period of 5 years from 2016 to 2020 and extracted nominal upper age cut-offs and the distribution of ages actually recruited. We identified 186 trials of 26,238 patients. We found that only 4.8% of trials could be applied to an “average” 75-year-old patient. This age-based exclusion was not dependent on funding source. Age-based exclusion was exacerbated by explicit upper age cut-offs, however, the age-based exclusion went beyond explicit age cut-offs. Only few trials were applicable to older patients even amongst trials with no age cut-off specified. Age-based exclusion from clinical trials starts at late middle age. The mismatch between spinal patient’s age seen in clinical practice and spinal patient’s age in trials was so severe that over the 5 years (2016–2020) almost no RCT evidence was produced applicable to the “average” aged-patient across the body of literature available. In conclusion, age-based exclusion is ubiquitous, multifactorial, and happens on a supratrial level. Eliminating age-based exclusion involves more than an arbitrary lifting of explicitly stated upper age cut-offs. Instead, recommendations include increasing input from geriatricians and ethics committees, establishing updated or new models of cares, and creating new protocols to facilitate further research.

BMP13 Prevents the Effects of Annular Injury in an Ovine Model

Publisher: Ivyspring International Publisher

Date: 2009

DOI: 10.7150/IJBS.5.388

Localization of Nitric Oxide Synthases During Fracture Healing

Publisher: Wiley

Date: 08-2002

DOI: 10.1359/JBMR.2002.17.8.1470

Abstract: Previously, we have reported that nitric oxide synthases (NOSs), which generate NO, modulate fracture healing. However, the cellular sources of the NOS isoforms during the course of fracture healing have not been studied systematically. The purpose of this study was to localize the cellular distribution of NOS isoforms (inducible NOS [iNOS], endothelial NOS [eNOS], and neuronal NOS [bNOS]) by in situ hybridization and immunohistology after femoral fractures in rats. The iNOS signal was detected during the initial stages (on day 4 and day 7) of fracture healing in 52 +/- 2% (mean +/- SE, n = 7) of cells within the intramembranous region, along the edge of the periosteal callus. The iNOS signal in callus cells declined to an undetectable level on day 14. eNOS was detected during the middle stages (on day 7 and day 14) of fracture healing in cells lining the blood vessels and also in 49 +/- 3% of cells in the chondral region. The bNOS signal was found to be increased at the later stages (day 14 and day 21) of fracture healing in 51 +/- 3% of cells at the junction between fibrous tissue and cartilage within the fibrochondral region. In summary, the,expression of NOS isoforms during fracture healing was time dependent and cellular distinctive.

A high-energy electron scattering study of the electronic structure and elemental composition of O-implanted Ta films used for the fabrication of memristor devices

Publisher: AIP Publishing

Date: 20-08-2013

DOI: 10.1063/1.4818524

Abstract: High-energy electron scattering is used to investigate Ta films implanted with 10 keV O ions. These films are of interest as they have been used for the fabrication of memristors. High-energy electron scattering is used with incoming electron energies ranging from 5 to 40 keV. The inelastic mean free path, and hence the probing depth, is at these energies of the same order as the range of the implanted ions. At the same time, we can distinguish the mass of the atom that scattered the electron elastically, due to the dependence of the recoil energy on the mass of the scatterer. This allows us to determine quantitatively the atomic composition near the surface from the signal of electrons that have scattered elastically but not inelastically. Electrons that have scattered inelastically as well as elastically provide us with information on the possible electronic excitations. Their signal is used to monitor the presence of the Ta2O5 phase near the surface (characterised by a significant band gap of ≃4.5 eV), and estimate at what depth below the surface pure Ta metal is present. In this way, we obtain a fairly detailed picture of the elemental composition and electronic properties of these films.

Are Fast-Bowlers Prone to Back Injuries? Prevalence of Lumbar Spine Injuries in Fast-Bowlers: Review of MRI-Based Studies

Publisher: Briefland

Date: 11-2014

DOI: 10.5812/ASJSM.24291

ISSLS PRIZE IN BASIC SCIENCE 2018: Growth differentiation factor-6 attenuated pro-inflammatory molecular changes in the rabbit anular-puncture model and degenerated disc-induced pain generation in the

Publisher: Springer Science and Business Media LLC

Date: 19-02-2018

DOI: 10.1007/S00586-018-5488-1

Interpedicular kinematics in an in vitro biomechanical assessment of a bilateral lumbar spondylolytic defect

Publisher: Elsevier BV

Date: 12-2014

DOI: 10.1016/J.CLINBIOMECH.2014.10.002

Abstract: A spondylolytic defect in lumbar vertebra is a common condition during early childhood and adolescence, and is considered a precursor to spondylolisthesis. This study examined whether a bilateral spondylolytic defect in lumbar spine intrinsically results in increased intervertebral translations during different bending motions. Seven fresh frozen cadaveric kangaroo lumbar (L1-L6) spine specimens were tested in a kinematic spine simulator first in their intact state, followed by creating a bilateral spondylolytic defect at L4 and retesting. In addition to recording global and segmental range of motions, the pedicles at L3, L4, and L5 vertebrae were digitized bilaterally and virtually tracked throughout testing. Interpedicular kinematic metrics were employed to capture any changes in translatory motions during flexion-extension, bilateral bending, and axial torsion testing modes. Following the defect, range of motion at the defect level (L4-L5) increased significantly in all the three motion planes. At L4-L5, normalized interpedicular displacement increased significantly in flexion-extension (median change +156%) and bilateral bending (median change +58%) motions, but changes in bending-plane and out-of-plane intervertebral translations were not significant in any of the testing modes. In the absence of any significant changes in bending-plane and out-of-plane intervertebral translations at L4-L5, changes in interpedicular displacement would directly correspond with the stretching of posterior annulus of the L4-L5 intervertebral disc. A bilateral spondylolytic defect at L4 may result in significant overstretching of the posterior annulus of the L4-L5 disc during flexion-extension and bilateral bending motions.

Effect of Electrode Roughness on Electroforming inHfO

Publisher: American Physical Society (APS)

Date: 29-12-2015

DOI: 10.1103/PHYSREVAPPLIED.4.064010

High-endurance megahertz electrical self-oscillation in Ti/NbOx bilayer structures

Publisher: AIP Publishing

Date: 25-05-2015

DOI: 10.1063/1.4921745

Abstract: Electrical self-oscillation is reported for a Ti/NbOx negative differential resistance device incorporated in a simple electric circuit configuration. Measurements confirm stable operation of the oscillator at source voltages as low as 1.06 V, and demonstrate frequency control in the range from 2.5 to 20.5 MHz for voltage changes as small as ∼1 V. Device operation is reported for & .5 × 1010 cycles, during which the operating frequency and peak-to-peak device current decreased by ∼25%. The low operating voltage, large frequency range, and high endurance of these devices makes them particularly interesting for applications such as neuromorphic computing.

Schottky-Barrier-Induced Asymmetry in the Negative-Differential-Resistance Response of Nb<

Publisher: American Physical Society (APS)

Date: 09-06-2020

DOI: 10.1103/PHYSREVAPPLIED.13.064024

The association between pain scores and disc height change following discectomy surgery in lumbar disc herniation patients: a systematic review and meta-analysis

Publisher: Springer Science and Business Media LLC

Date: 10-06-2021

DOI: 10.1007/S00586-021-06891-4

Universal Dynamics Analysis of Locally-Active Memristors and its Applications

Publisher: Institute of Electrical and Electronics Engineers (IEEE)

Date: 03-2022

DOI: 10.1109/TCSI.2021.3130938

Technical note: the swimmer’s view for cervical facet joint injections

Publisher: Springer Science and Business Media LLC

Date: 05-05-2006

DOI: 10.1007/S00586-006-0123-Y

Failed degenerative lumbar spine surgery

Publisher: Elsevier BV

Date: 04-2003

DOI: 10.1016/S0030-5898(03)00028-2

Abstract: Significant back and leg symptoms develop in approximately 10%-15% of patients who have undergone a spinal decompression procedure and approximately 15%-20% of patients who have had a spinal fusion procedure for degenerative disease of the lumbar spine during the ensuing 3-5 year so that they require revision lumbar surgery. The cause for their symptoms has to be diligently looked for, as that is a main predictor of good outcome following revision surgery. Good history taking, including a detailed old chart review, repeat physical evaluation, and input from therapists--physical and psychological, neurologist, and other caregivers--should be sought. These, together with intelligent use of investigations, go a long way in helping establish a cause for failure. Furthermore, developing a revision surgical strategy is also an intellectual exercise in which a simple algorithmic approach may not always work. The process of evaluation and surgical management for failed lumbar degeneration is a science and an art that requires a great deal of understanding and commitment on the part of the surgeon. The temporal trend of improving outcomes is aided in part by emerging technologies, however, one has to be constantly aware of simple factors that influence outcome. The use of published literature and experiences of peers helps one offer appropriate surgical intervention while improving the long-term results of revision surgery of the lumbar spine.

Therapeutic potential of growth differentiation factors in the treatment of degenerative disc diseases

Publisher: Wiley

Date: 03-2019

DOI: 10.1002/JSP2.1045

BMP-2 Enhances TGF-β3–Mediated Chondrogenic Differentiation of Human Bone Marrow Multipotent Mesenchymal Stromal Cells in Alginate Bead Culture

Publisher: Mary Ann Liebert Inc

Date: 06-2009

DOI: 10.1089/TEN.TEA.2008.0132

Abstract: This study addresses synergistic effects of bone morphogenetic protein-2 (BMP-2) and transforming growth factor-beta3 (TGF-beta3) in the induction of chondrocytic differentiation of bone marrow multipotent mesenchymal stromal cells (BM MSCs) in vitro for potential use in intervertebral disc (IVD) repair. Human BM MSCs encapsulated in alginate beads were induced to differentiate in serum-free medium containing BMP-2 and TGF-beta3. The expression of chondrocytic genes and proteins was analyzed by real-time PCR, western blot, histological, and immunohistochemical assays. This differentiation system showed a potent induction of chondrocytic phenotypes. The expression of chondrocytic markers, such as aggrecan (ACAN) and type II collagen (COL2A1), was upregulated at higher levels than using TGF-beta3 alone. Blocking BMP-2 by noggin completely suppressed BMP-2-enhanced gene and protein expression, confirming a crucial input of BMP-2 signaling in this differentiation process. Inhibition of extracellular signal-regulated kinases 1 and 2 signaling resulted in an increase in ACAN and COL2A1 gene expression, suggesting a negative regulatory role of this pathway. In conclusion, BMP-2 enhances TGF-beta3-mediated chondrogenesis of MSCs. The combination of BMP-2 and TGF-beta3 in alginate culture is superior to the standard differentiation method using TGF-beta alone. This potent induction system may provide an alternative cell source for IVD and cartilage regeneration in clinical practice.

Posterolateral Intertransverse Spinal Fusion Possible in Osteoporotic Rats With BMP-7 in a Higher Dose Delivered on a Composite Carrier

Publisher: Ovid Technologies (Wolters Kluwer Health)

Date: 02-2008

DOI: 10.1097/BRS.0B013E318162451B

Nanoindentation of Si Nanocrystals in SiO_2

Publisher: IEEE

Date: 2005

DOI: 10.1109/COMMAD.2004.1577559

Strong paramagnetism and possible ferromagnetism in pure carbon nanofoam produced by laser ablation

Publisher: Elsevier BV

Date: 04-2005

DOI: 10.1016/J.JMMM.2004.11.213

Annular closure device for disc herniation: meta-analysis of clinical outcome and complications

Publisher: Springer Science and Business Media LLC

Date: 16-08-2018

DOI: 10.1186/S12891-018-2213-5

Intrinsic variables associated with low back pain and lumbar spine injury in fast bowlers in cricket: a systematic review

Publisher: Springer Science and Business Media LLC

Date: 20-09-2023

DOI: 10.1186/S13102-023-00732-1

Electronic and magnetic properties of carbon nanofoam produced by high-repetition-rate laser ablation

Publisher: Elsevier BV

Date: 09-2002

DOI: 10.1016/S0169-4332(02)00433-6

University Of New South Wales

Location: Australia

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Royal Australasian College Of Surgeons

Location: Australia

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Hospital For Special Surgery

Location: United States of America

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Linkage Infrastructure, Equipment And Facilities - Grant ID: LE0453320

Start Date: 01-2004

End Date: 12-2005

Amount: $347,886.00

Funder: Australian Research Council

Special Research Initiatives - Grant ID: SR0354658

Start Date: 01-2004

End Date: 12-2003

Amount: $10,000.00

Funder: Australian Research Council

Linkage Infrastructure, Equipment And Facilities - Grant ID: LE0453521

Start Date: 2003

End Date: 12-2004

Amount: $508,374.00

Funder: Australian Research Council

Linkage Infrastructure, Equipment And Facilities - Grant ID: LE0775729

Start Date: 2007

End Date: 12-2008

Amount: $420,000.00

Funder: Australian Research Council

Research Networks - Grant ID: RN0458455

Start Date: 07-2004

End Date: 06-2009

Amount: $1,500,000.00

Funder: Australian Research Council

Linkage Infrastructure, Equipment And Facilities - Grant ID: LE110100127

Start Date: 2011

End Date: 06-2011

Amount: $250,000.00

Funder: Australian Research Council

Linkage Infrastructure, Equipment And Facilities - Grant ID: LE100100121

Start Date: 04-2010

End Date: 08-2012

Amount: $1,000,000.00

Funder: Australian Research Council

Linkage Infrastructure, Equipment And Facilities - Grant ID: LE100100048

Start Date: 04-2010

End Date: 12-2011

Amount: $340,000.00

Funder: Australian Research Council

Linkage Infrastructure, Equipment And Facilities - Grant ID: LE0882816

Start Date: 08-2008

End Date: 05-2009

Amount: $500,000.00

Funder: Australian Research Council

Special Research Initiatives - Grant ID: SR0354735

Start Date: 2003

End Date: 12-2003

Amount: $10,000.00

Funder: Australian Research Council

Research Networks - Grant ID: RN0459611

Start Date: 07-2004

End Date: 12-2010

Amount: $1,900,000.00

Funder: Australian Research Council