ORCID Profile
0000-0001-9601-9109
Current Organisations
Auckland University of Technology
,
Skin Surgery Clinic
,
University of Queensland School of Medicine
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Publisher: Sci Forschen, Inc.
Date: 2021
Abstract: Objective: The primary aim of this study was to evaluate the performance of a commercially manufactured study product-a non-toxin-based topical skin serum-in terms of its wrinkle reducing capability in women concerned about the appearance of their wrinkles.
Publisher: Georg Thieme Verlag KG
Date: 05-2017
DOI: 10.5999/APS.2017.44.3.243
Abstract: Reconstruction of the lower limb presents a complex problem after skin cancer surgery, as proximity of skin and bone present vascular and technical challenges. Studies on vascular anatomy have confirmed that the vascular plane on the lower limb lies deep to the deep fascia. Yet, many flaps are routinely raised superficial to this plane and therefore flap failure rates in the lower limb are high. Fascio-cutaneous flaps based on perforators offer a better cosmetic alternative to skin grafts. In this paper, we detail use of a thermal imaging camera to identify perforator ‘compartments’ that can help in designing such flaps.
Publisher: Springer International Publishing
Date: 2017
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 12-2017
DOI: 10.1097/GOX.0000000000001614
Abstract: Closing of defects of the lower limb after skin cancer excision poses a challenge in lower limb skin. Although the concept of relaxed skin tension lines has been established as ideal on the face, on the lower limb there remains confusion between Langer’s lines and wrinkle lines, and this study was done with the task of identifying and mapping biodynamic excisional skin tension (BEST) lines on the lower limb. Following studies on BEST lines elsewhere on the body, the author investigated BEST lines on the lower limb. Using a specially designed tensiometer, inherent skin tension (pretension) and wound-closing tension were studied along with the force needed to bring the wound edges together after excision of a lesion in 23 cases with defects ranging from 1.5 to 4.5 cm in diameter. Skin tension measurements of skin lines (relaxed skin tension lines (RSTL) versus BEST) and vertical closure (BEST) versus vertical closure with a parallel relaxing incision were undertaken and followed by statistical analyses utilizing the paired t test and the unpaired Student’s t tests. BEST lines run in the vertical direction on the lower limb, that is, closure in a vertical direction resulted in a statistically significant reduction in closing tension when compared with other directions. Using a parallel relaxing incision can offer further reduction in tension, if needed. BEST lines of the lower limb are discussed, and a new technique of using parallel relaxing incisions to achieve closure of larger defects is also presented as an alternative to cutaneous flaps or grafts in the lower limb.
Publisher: Scientific Research Publishing, Inc.
Date: 2017
Publisher: Royal College of Surgeons of England
Date: 04-2018
Abstract: There remains confusion between Langer’s lines and wrinkle lines with respect to the optimal orientation of elliptical excisions on the trunk. This study sought to determine the directions of wound closure that would result in least wound tension after skin lesion excisions. Some 1181 consecutive skin lesion excisions were investigated (age range 13–95 years, median 64 years) using a tensiometer to determine directions of least wound tension. These lines were mapped. Skin tension measurements were taken during the procedure and analysed. The clear majority of excisions were for skin cancer and the others were for cysts or dysplastic naevi. Lesions such as lipomas, which entail incisional rather than excisional surgery (i.e. where overlying skin was not excised) were excluded. All lesions were cut out in a circular fashion following tension measurements. Closure was undertaken in the direction of least tension (biodynamic excisional skin tension line) and this was illustrated. This process was repeated in all cases where body site and direction of closure was mapped. Statistical analyses were undertaken on a series on the scalp and lower limb. Biodynamic excisional skin tension lines have a clear directional preference: scalp–coronal direction, limbs-–vertical orientation of ellipses and trunk – mostly horizontal except oblique at the shoulder and scapular regions. Skin cancer excisions often end up with poor cosmetic results, owing to inconsistency in identifying the correct excisional wound closure lines. This has not been helped by the (hitherto) lack of large in vivo biomechanical studies, and because incisional lines and excisional lines have not been considered separately in surgical practice. Orientating ellipses or wound closures using biodynamic excisional skin tension lines offers a guide to reducing wound tension and minimising wound complications or scarring after cutaneous surgery.
Publisher: International Medical Research and Development Corporation
Date: 16-06-2017
Publisher: American Society of Mechanical Engineers
Date: 03-11-2018
Abstract: There is an increased risk of melanoma in adulthood when a child (pre-puberty) has been exposed to high levels of ultraviolet radiation (UVR). It has also been hypothesized that the childhood body air (vellus hair) plays a role in the increased incidence of melanoma later in life. This is attributed to the fact that the vellus hair has properties and physiology which encourage the transmission of harmful energy into the follicle of the hair and ultimately cause damage to the stem cells in residence there. Later in life these damaged stem cells become involved in the generation of melanomas in the epidermis. It has been debated whether the UVR or the heat generated by it is the main contributor to melanoma occurrence. This research is the first step in investigating this phenomenon by focusing on the contribution of changes in thermal characteristics on the incidence of melanoma. To test the hypothesis that child hair can transmit energy more easily than adult hair the transient electro-thermal technique is used to determine the thermal diffusivity of the hair. This involved subjecting platinum coated hair s les to a current pulse and measuring the subsequent voltage response in the s le. Results show that the child hair has a thermal diffusivity around two times higher than adult hair, thus supporting the hypothesis. Further research will be needed, in particular, quantifying the optical transmission characteristics of child hair compared to adult hair.
Publisher: JMIR Publications Inc.
Date: 26-06-2023
Publisher: Frontiers Media SA
Date: 04-09-2019
Publisher: American Society of Mechanical Engineers
Date: 11-11-2020
Abstract: The role human hair plays on the solar ultraviolet (UV) transmission in the skin has been investigated regarding melanoma development in our previous work. However, due to the lack of knowledge about the optical properties of human hair medulla, hair has always been modelled as a homogenous structure in Monte Carlo (MC) simulations of photon transport in skin. In this paper, we have estimated the ratio range of the absorption to attenuation coefficient of hair medulla, in order to examine how the presence of medulla would affect the solar UV transmission in the skin. This was simulated in TracePro™ software with the implementation of the MC method for photon transport. The results show that medullated and non-medullated terminal hairs have similar shielding effects against solar UV transmission into skin.
Publisher: Springer International Publishing
Date: 2016
Publisher: Public Library of Science (PLoS)
Date: 09-2016
Publisher: Frontiers Media SA
Date: 16-11-2016
Publisher: Springer International Publishing
Date: 2018
Publisher: Elsevier BV
Date: 10-2023
Publisher: Springer International Publishing
Date: 2018
Publisher: JMIR Publications Inc.
Date: 30-10-2023
DOI: 10.2196/50309
Publisher: Hindawi Limited
Date: 2017
DOI: 10.1155/2017/1536434
Abstract: Follicular urate-like crystals were first described in Necrotizing Infundibular Crystalline Folliculitis (NICF), a rare cutaneous disorder with multiple waxy folliculocentric papules. Similar crystal accumulation may be seen within follicular infundibulae as an incidental finding. We describe a case showing identical crystals occurring within the horn-like crusts of a patient with erosive pustular dermatosis of the scalp (EPDS), a condition which due to its presentation can often be mistaken for nonmelanoma skin cancer. A brief overview of erosive pustular dermatosis of the scalp (EPDS) is presented in this paper.
Publisher: Optica Publishing Group
Date: 23-04-2020
DOI: 10.1364/JOSAA.387558
Abstract: Melanoma is the severest type of skin cancer. As distinct from many other cancer types, the incidence of melanoma has been increasing steadily over the last century. Discovering new risk factors of melanoma will not only raise public awareness but also potentially contribute to the improvement of skin cancer protection in the future. Nowadays, the tendency of shaving skin hair is becoming increasingly popular for aesthetic purposes. However, human hair serves several functions, one of which is ultraviolet (UV) protection for the skin. What is more, stem cells found in the follicles of hair could be the origin of melanoma upon exposure to ultraviolet radiation. Therefore, it is of interest to investigate the effect of shaving on solar UV transmission in the skin. To achieve that, two groups of skin models are constructed in TracePro software: one with unaltered hair and one with shaved hair. The UV transport in the models is simulated using the Monte Carlo method and the absorptions in the stem cells layer are compared. It is found that shaving will increase the UV transmission to the follicular stem cells to a certain degree. More specifically, shaving limbs will generally increase the solar UV transmission from about 5% to 20% in the UV wavelength range.
Publisher: Springer Science and Business Media LLC
Date: 09-07-2019
DOI: 10.1007/S10439-019-02315-Z
Abstract: Melanoma is the deadliest type of skin cancer with its prevalence on the rise. Recently, the melanocyte stem cells in hair follicles have been identified as the possible origin of melanoma upon exposure to ultraviolet radiation (UVR) through skin. It is hypothesized that colourless vellus hair (predominant in childhood) can serve as an alternative pathway in transmitting these ultraviolet (UV) photons to the stem cells. To investigate this, we have used the CRAIC microspectrophotometer to investigate the optical properties of 'vellus-like' hairs and terminal hairs of different colours using UV-VIS-NIR light sources. It was found that the average attenuation coefficient of 'vellus-like' hair is significantly lower than that of terminal hair in the UVA (p < 0.0001) and UVB (p < 0.001) wavelength ranges. Next, the optical properties of hairs are applied to simulations for examining their influence on UV transmission into the skin. The results show that the presence of vellus hair would increase the solar UV transmission to the melanocyte stem cell layer significantly. The findings explain why children are particularly vulnerable to sun exposure and the positive correlation found between the incidence of melanoma in adults' bodies and the number of vellus hairs in these areas.
Publisher: University of Queensland Library
Date: 2021
DOI: 10.14264/43DF65A
Publisher: The Optical Society
Date: 22-03-2019
Publisher: Cold Spring Harbor Laboratory
Date: 23-03-2016
DOI: 10.1101/043992
Abstract: This paper began as an exercise in curiosity – logarithmic spiral designs abound in nature ‐‐ in galaxies, flowers, pinecones and on human scalps as whorls. Why are humans the only primates to have whorls on the scalp? Is the formation of scalp whorls mechanical or genetic? A mechanical theory has long been postulated– the mechanical theory suggests that hair whorl patterning is determined by the tension on the epidermis during rapid expansion of the cranium while the hair follicle is growing downwards – however, this has never before been experimentally proven conclusively. We found, that under certain conditions, we were able to experimentally recreate spirals on the scalp to demonstrate that the basis of scalp whorls is indeed mechanical – and that logarithmic spirals are indeed nature’s own design for rapid expansion of organic tissues. Given our experiments only created whorls when certain conditions were satisfied (and not in others), they have given us great insight into the mechanical formation of skin whorls and the physiology of skin stretch. We believe that these findings will lead to many more advances in understanding skin dynamics and indeed the behavior of any living tissue when confronted by stretch. As a corollary, the application of the results of these studies have led us to the discovery of a new surgical technique for closure of scalp defects using the golden spiral pattern, and this will be the subject of a separate paper.
Publisher: Springer Science and Business Media LLC
Date: 14-07-2021
DOI: 10.1186/S13256-021-02920-4
Abstract: We present an unusual case of a patient who developed four melanomas within a few months of diagnosis with human immunodeficiency virus and commencement of highly active antiretroviral therapy therapy. The patient had no previous history of melanoma, and previous skin checks were normal. A 50-year-old Caucasian male drainlayer with Fitzpatrick type 2 skin presented for a routine skin examination. He had been diagnosed with human immunodeficiency virus 4 months earlier and commenced on highly active antiretroviral therapy therapy. He was found to have three melanomas (melanoma in situ stage) on excision biopsies, and when he presented for wider excisions of these sites a few weeks later, another new melanoma in situ was found. He had no other medical history of note, and no symptoms to report. He is being followed up 3-monthly. This case of a human immunodeficiency virus-positive person presenting with four cutaneous melanomas—occurring in both synchronous and metachronous fashion within a 4-month period—is being presented both for its uniqueness and also to highlight the increased need for close skin surveillance in human immunodeficiency virus-positive patients.
No related grants have been discovered for Sharad Paul.