ORCID Profile
0000-0002-8248-6379
Current Organisations
University of New South Wales
,
Curtin University
,
Telethon Kids Institute
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In Research Link Australia (RLA), "Research Topics" refer to ANZSRC FOR and SEO codes. These topics are either sourced from ANZSRC FOR and SEO codes listed in researchers' related grants or generated by a large language model (LLM) based on their publications.
Epidemiology | Biostatistics | Environmental Science and Management | Ecological Applications | Community Ecology | Conservation and Biodiversity | Landscape Ecology |
Expanding Knowledge in the Environmental Sciences | Expanding Knowledge in the Biological Sciences | Disease Distribution and Transmission (incl. Surveillance and Response) | Flora, Fauna and Biodiversity at Regional or Larger Scales | Forest and Woodlands Flora, Fauna and Biodiversity
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 03-2019
DOI: 10.1097/OPX.0000000000001354
Abstract: Microblepharon exfoliation improved eyelid signs and tear film characteristics after a single in-office treatment in symptomatic contact lens wearers. The purpose of this study was to assess the effect of two eyelid hygiene treatments—microblepharon exfoliation and a hypoallergenic foam cleanser (LidHygenix)—on clinical signs of the eyelids, meibomian glands, and tear film in contact lens discomfort. A randomized, interventional, unmasked, crossover trial was conducted on 30 experienced daily-wear soft contact lens wearers. Assessment of clinical signs of the eyelid margin, meibomian gland morphology and secretion, and tear film biophysical properties was performed (baseline 1), and participants were randomly assigned to receive one of the two treatments (microblepharon exfoliation or foam cleansing using LidHygenix) as a single in-office procedure. Symptoms were evaluated using the Contact Lens Dry Eye Questionnaire-8 immediately after treatment, and assessment of all the study variables was repeated at the follow-up visit 7 to 10 days after treatment. After 28 to 30 days of washout, participants returned for reassessment of the study variables (baseline 2) and were crossed over to receive the alternate treatment. Follow-up was repeated 7 to 10 days after the second treatment. Seven to 10 days after treatment with microblepharon exfoliation, symptomatic wearers showed significant improvement in anterior blepharitis (mean difference, 0.60 P = .04), lid wiper staining (0.50 P = .06), and lid-parallel conjunctival folds (0.68, P = .02) along with orifice capping (median difference, 0.65 P .001), foam (0.90 P .001), secretion volume (0.69 P .001), quality (0.74 P .001), and expressibility (0.49 P = .002), which were also clinically significant changes. However, in tear properties, significant improvements were observed in tear volume (LidHygenix, −1.25 mm microblepharon exfoliation, −1.62 mm), break-up time (−0.14 seconds −0.14 seconds), tear evaporation rate without contact lenses (21.52 g m −2 h 45.43 g m −2 h), and lipid layer thickness (−20.61 nm −25.13 nm) after both treatments but in symptomatic lens wearers only ( P .05). Microblepharon exfoliation improved eyelid signs and tear film characteristics in symptomatic contact lens wearers after a single in-office treatment.
Publisher: Informa UK Limited
Date: 2008
DOI: 10.1080/02713680802140213
Abstract: Previously, we reported carboxymethyl cellulose (CMC) binding to human corneal epithelial cells and promoting corneal epithelial wound closure in vitro. Using an animal model, the efficacy of CMC in promoting corneal wound healing was examined. Following corneal epithelial wounding of NZ white rabbits, CMC (0.2% or 1.0%) or control vehicle (PBS) was administered topically (4 times daily for 3 days) to wounded and unwounded eyes with or without contact lens wear. Wound healing in response to the treatments was measured as percentage reduction of fluorescein-stained wound area 0 to 72 hr post-wounding. Corneas were examined histologically and expression of zonula occludens-1 (ZO-1) tight-junction was detected by immunohistochemistry. Percentage wound reduction in CMC-treated groups was significantly greater than controls (p < 0.05) at 24 and 32 hr. Complete wound closure was observed by 48 hr in 100% of CMC-treated eyes compared to 45% of vehicle-treated eyes. CMC also promoted wound closure dose-dependently. Epithelial cells formed an intact layer following CMC-treatment whereas vehicle-treated cells were less ordered. Strong ZO-1 expression in corneal epithelia of CMC-treated eyes was observed at 72 hr. Contact lens wear appeared to delay wound closure compared to without lens wear during CMC-treatment (p = 0.001). CMC promoted dose-dependent corneal epithelial wound healing. CMC stimulated ZO-1 expression, indicating accelerated corneal epithelial resistance barrier regeneration.
Publisher: MDPI AG
Date: 15-10-2018
DOI: 10.3390/ANTIBIOTICS7040088
Abstract: Background: The prevalence of disinfectant resistance in Pseudomonas aeruginosa is on the rise. P. aeruginosa is the most common bacteria isolated from cases of microbial keratitis. Many multi-purpose contact lens disinfectant solutions are available to decontaminate contact lenses before use and to help reduce the incidence of infections. However, with increasing disinfectant resistance, the effect of multi-purpose disinfectant solutions may diminish. The goal of this study was to examine genes associated with disinfectant resistance in ocular isolates of P. aeruginosa and understand the strain’s susceptibility to different multipurpose disinfectant solutions. Methods: Seven potential disinfectant resistance genes were used in BLASTn searches against the whole genomes of 13 eye isolates of P. aeruginosa. A microdilution broth method was used to examine susceptibility to four different multipurpose disinfectant solutions. Results: All strains possessed the sugE2, sugE3 and emrE (qacE) genes. The sugE1 and qacEdelta1 genes were present in 6/13 isolates. No strains contained the qacF or qacG genes. All tested disinfectant solutions had the ability to kill all test strains at 100% concentration, with some strains being susceptible at 1:8 dilutions of the disinfecting solutions. However, the presence of disinfectant resistance genes was not associated with susceptibility to multi-purpose disinfectants. Conclusion: All four tested contact lens disinfectant preparations are effective against P. aeruginosa isolates regardless of the presence of disinfectant resistance genes.
Publisher: Wiley
Date: 20-10-2021
DOI: 10.1111/GCB.15888
Abstract: Due to global climate change–induced shifts in species distributions, estimating changes in community composition through the use of Species Distribution Models has become a key management tool. Being able to determine how species associations change along environmental gradients is likely to be pivotal in exploring the magnitude of future changes in species’ distributions. This is particularly important in connectivity‐limited ecosystems, such as freshwater ecosystems, where increased human translocation is creating species associations over previously unseen environmental gradients. Here, we use a large‐scale presence–absence dataset of freshwater fish from lakes across the Fennoscandian region in a Joint Species Distribution Model, to measure the effect of temperature on species associations. We identified a trend of negative associations between species tolerant of cold waters and those tolerant of warmer waters, as well as positive associations between several more warm‐tolerant species, with these associations often shifting depending on local temperatures. Our results confirm that freshwater ecosystems can expect to see a large‐scale shift towards communities dominated by more warm‐tolerant species. While there remains much work to be done to predict exactly where and when local extinctions may take place, the model implemented provides a starting‐point for the exploration of climate‐driven community trends. This approach is especially informative in regards to determining which species associations are most central in shaping future community composition, and which areas are most vulnerable to local extinctions.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 29-11-2020
Publisher: MDPI AG
Date: 30-08-2023
DOI: 10.20944/PREPRINTS202308.2017.V1
Abstract: The development of potent antiviral agents is of utmost importance to combat the global burden of viral infections. Traditional antiviral drug development involves targeting specific viral proteins, which may lead to the emergence of resistant strains. To explore alternative strategies, we investigated the antiviral potential of antimicrobial peptidomimetic compounds. In this study, we evaluated the antiviral potential of short anthranilamide-based peptidomimetic compounds 1-17 against two viruses: Murine Hepatitis Virus 1 (MHV-1-single stranded RNA virus) which is a surrogate of human coronaviruses and Herpes Simplex Virus 1 (HSV-1-double stranded DNA virus). The half-maximal inhibitory concentration (IC50) values of these compounds were determined in vitro to assess their potency as antiviral agents. Compounds 11 and 14 displayed the most potent inhibitory effect with IC50 values of 2.38μM, and 6.3μM against MHV-1 while compounds 9 and 14 showed IC50 values of 14.8μM and 13μM, against HSV-1. Multiple antiviral assessments and microscopic images obtained through transmission electron microscopy (TEM) collectively demonstrated that these compounds exert a direct influence on the viral envelope. Based on this outcome, it can be concluded that peptidomimetic compounds could offer a new approach for the development of potent antiviral agents.
Publisher: Springer Science and Business Media LLC
Date: 23-10-2018
DOI: 10.1038/S41598-018-34020-7
Abstract: The large and complex genome of Pseudomonas aeruginosa , which consists of significant portions (up to 20%) of transferable genetic elements contributes to the rapid development of antibiotic resistance. The whole genome sequences of 22 strains isolated from eye and cystic fibrosis patients in Australia and India between 1992 and 2007 were used to compare genomic ergence and phylogenetic relationships as well as genes for antibiotic resistance and virulence factors. Analysis of the pangenome indicated a large variation in the size of accessory genome amongst 22 stains and the size of the accessory genome correlated with number of genomic islands, insertion sequences and prophages. The strains were erse in terms of sequence type and dissimilar to that of global epidemic P . aeruginosa clones. Of the eye isolates, 62% clustered together within a single lineage. Indian eye isolates possessed genes associated with resistance to aminoglycoside, beta-lactams, sulphonamide, quaternary ammonium compounds, tetracycline, trimethoprims and chlor henicols. These genes were, however, absent in Australian isolates regardless of source. Overall, our results provide valuable information for understanding the genomic ersity of P . aeruginosa isolated from two different infection types and countries.
Publisher: Springer Science and Business Media LLC
Date: 26-02-2021
DOI: 10.1038/S41598-021-84198-6
Abstract: Understanding human movement patterns at local, national and international scales is critical in a range of fields, including transportation, logistics and epidemiology. Data on human movement is increasingly available, and when combined with statistical models, enables predictions of movement patterns across broad regions. Movement characteristics, however, strongly depend on the scale and type of movement captured for a given study. The models that have so far been proposed for human movement are best suited to specific spatial scales and types of movement. Selecting both the scale of data collection, and the appropriate model for the data remains a key challenge in predicting human movements. We used two different data sources on human movement in Australia, at different spatial scales, to train a range of statistical movement models and evaluate their ability to predict movement patterns for each data type and scale. Whilst the five commonly-used movement models we evaluated varied markedly between datasets in their predictive ability, we show that an ensemble modelling approach that combines the predictions of these models consistently outperformed all in idual models against hold-out data.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 26-05-2021
DOI: 10.1097/OPX.0000000000001700
Abstract: A multipurpose disinfecting solution (MPDS), which contains povidone-iodine (PI) as a disinfectant, has high disinfecting efficacy not only on planktonic bacterium but also on the case biofilms. The addition of case hygiene practice removed more bacteria from cases than MPDS alone. This study compared the ability of two MPDSs, one containing PI and another containing polyaminopropyl biguanide and polyquaternium, to reduce bacterial numbers in solution or adhered to the cases following case hygiene procedures. Bacterial strains ( Delftia acidovorans , Pseudomonas aeruginosa , Stenotrophomonas maltophilia , Serratia marcescens , Staphylococcus aureus , and Staphylococcus epidermidis ) were exposed to the MPDSs for the recommended disinfection times, and the viable number evaluated according to ISO 14729. Cases were inoculated with bacterial strains and incubated for 24 hours to allow for biofilm formation. Cases were disinfected with both disinfecting solutions for 4 hours and rinsed, followed by recapping or air-drying, or tissue-wiping and air-drying for 18 hours. The number of survivors was counted using standard culture techniques. Both products exceeded the recommended 3-log reduction against planktonic bacteria. Regarding biofilm, after rinsing and recapping wet, the numbers of D. acidovorans (mean difference [95% confidence interval] log 10 colony-forming units per case, −2.9 [0.8 to −4.6], P .01) , P. aeruginosa (−2.0 [0.5 to −3.1], P .01), S. marcescens (−1.7 [0.8 to −3.5], P .05), and S. epidermidis (−2.1 [0.6 to −3.5], P .05) in PI cases were significantly lower than in the dual-disinfectant MPDS storage cases. After air-drying, the PI storage cases had significantly lower numbers of S. maltophilia (−2.6 [0.6 to −4.0], P .01), D. acidovorans (−1.6 [0.7 to −3.3], P .05), and S. aureus (−1.6 [0.7 to −3.1], P .05). The addition of tissue-wiping reduced the bacterial numbers in the MPDS storage cases to levels in the PI storage cases. Contact lens users should be recommended to tissue-wipe and air-dry their lens storage cases after disinfection with regular MPDS.
Publisher: Springer Science and Business Media LLC
Date: 24-11-2018
DOI: 10.1038/EYE.2017.241
Publisher: eLife Sciences Publications, Ltd
Date: 13-08-2020
DOI: 10.7554/ELIFE.58785
Abstract: As of 1 May 2020, there had been 6808 confirmed cases of COVID-19 in Australia. Of these, 98 had died from the disease. The epidemic had been in decline since mid-March, with 308 cases confirmed nationally since 14 April. This suggests that the collective actions of the Australian public and government authorities in response to COVID-19 were sufficiently early and assiduous to avert a public health crisis – for now. Analysing factors that contribute to in idual country experiences of COVID-19, such as the intensity and timing of public health interventions, will assist in the next stage of response planning globally. We describe how the epidemic and public health response unfolded in Australia up to 13 April. We estimate that the effective reproduction number was likely below one in each Australian state since mid-March and forecast that clinical demand would remain below capacity thresholds over the forecast period (from mid-to-late April).
Publisher: Cold Spring Harbor Laboratory
Date: 06-08-2022
DOI: 10.1101/2022.08.04.22278391
Abstract: As of January 2021, Australia had effectively controlled local transmission of COVID-19 despite a steady influx of imported cases and several local, but contained, outbreaks in 2020. Throughout 2020, state and territory public health responses were informed by weekly situational reports that included an ensemble forecast for each jurisdiction. We present here an analysis of one forecasting model included in this ensemble across the variety of scenarios experienced by each jurisdiction from May to October 2020. We examine how successfully the forecasts characterised future case incidence, subject to variations in data timeliness and completeness, showcase how we adapted these forecasts to support decisions of public health priority in rapidly-evolving situations, evaluate the impact of key model features on forecast skill, and demonstrate how to assess forecast skill in real-time before the ground truth is known. Conditioning the model on the most recent, but incomplete, data improved the forecast skill, emphasising the importance of developing strong quantitative models of surveillance system characteristics, such as ascertainment delay distributions. Forecast skill was highest when there were at least 10 reported cases per day, the circumstances in which authorities were most in need of forecasts to aid in planning and response.
Publisher: Association for Research in Vision and Ophthalmology (ARVO)
Date: 21-10-2016
Abstract: To determine the ability of antimicrobial peptide melimine-coated contact lenses to reduce the incidence of microbial keratitis (MK) in a rabbit model of contact lens wear. In vitro antimicrobial activity of melimine-coated contact lenses was determined against Pseudomonas aeruginosa by viable count and a radiolabeled assay. The amount of lipopolysaccharide (LPS) associated with bacteria bound to melimine-coated and control lenses was determined. Ocular swabs from rabbit eyes were collected for assessment of ocular microflora. A rabbit model for MK was developed that used overnight wear of contact lenses colonized by P. aeruginosa in the absence of a corneal scratch. During lens wear, detailed ocular examinations were performed, and the incidence of MK was investigated. Bacteria associated with worn lenses and infected corneas were determined by viable plate count. Inhibition in viable and total P. aeruginosa adhesion by melimine-coated contact lenses was 3.1 log10 and 0.4 log10, respectively. After colonization, the amount of LPS on lenses was approximately the same with or without melimine. Gram-positive bacteria were found in all the ocular swabs followed by fungus (42%). Melimine-coated lens wear was protective and significantly (odds ratio 10.12 P = 0.012) reduced the incidence of P. aeruginosa-driven MK in the rabbit model. The antimicrobial lenses were associated with significantly (P < 0.001) lower ocular scores, indicating improved ocular signs compared with controls. This study showed that contaminated contact lenses can produce MK without corneal epithelial defect in an animal model. Melimine-coated contact lenses reduced the incidence of MK associated with P. aeruginosa in vivo. Development of MK requires viable bacteria adherent to contact lenses, and bacterial debris adherent at the lens surface did not cause keratitis.
Publisher: CSIRO Publishing
Date: 2019
DOI: 10.1071/MA19048
Publisher: Wiley
Date: 05-2014
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 03-2015
Publisher: MDPI AG
Date: 27-07-2022
DOI: 10.3390/ANTIBIOTICS11081011
Abstract: Staphylococcus aureus is a major cause of ocular infectious (corneal infection or microbial keratitis (MK) and conjunctivitis) and non-infectious corneal infiltrative events (niCIE). Despite the significant morbidity associated with these conditions, there is very little data about specific virulence factors associated with the pathogenicity of ocular isolates. A set of 25 S. aureus infectious and niCIEs strains isolated from USA and Australia were selected for whole genome sequencing. Sequence types and clonal complexes of S. aureus strains were identified by using multi-locus sequence type (MLST). The presence or absence of 128 virulence genes was determined by using the virulence finder database (VFDB). Differences between infectious (MK + conjunctivitis) and niCIE isolates from USA and Australia for possession of virulence genes were assessed using the chi-square test. The most common sequence types found among ocular isolates were ST5, ST8 while the clonal complexes were CC30 and CC1. Virulence genes involved in adhesion (ebh, clfA, clfB, cna, sdrD, sdrE), immune evasion (chp, esaD, esaE, esxB, esxC, esxD), and serine protease enzymes (splA, splD, splE, splF) were more commonly observed in infectious strains (MK + conjunctivitis) than niCIE strains (p = 0.004). Toxin genes were present in half of infectious (49%, 25/51) and niCIE (51%, 26/51) strains. USA infectious isolates were significantly more likely to possess splC, yent1, set9, set11, set36, set38, set40, lukF-PV, and lukS-PV (p 0.05) than Australian infectious isolates. MK USA strains were more likely to possesses yent1, set9, set11 than USA conjunctivitis strains (p = 0.04). Conversely USA conjunctivitis strains were more likely to possess set36 set38, set40, lukF-PV, lukS-PV (p = 0.03) than MK USA strains. The ocular strain set was then compared to 10 fully sequenced non-ocular S. aureus strains to identify differences between ocular and non-ocular isolates. Ocular isolates were significantly more likely to possess cna (p = 0.03), icaR (p = 0.01), sea (p = 0.001), set16 (p = 0.01), and set19 (p = 0.03). In contrast non-ocular isolates were more likely to possess icaD (p = 0.007), lukF-PV, lukS-PV (p = 0.01), selq (p = 0.01), set30 (p = 0.01), set32 (p = 0.02), and set36 (p = 0.02). The clones ST5, ST8, CC30, and CC1 among ocular isolates generally reflect circulating non-ocular pathogenic S. aureus strains. The higher rates of genes in infectious and ocular isolates suggest a potential role of these virulence factors in ocular diseases.
Publisher: Elsevier BV
Date: 04-2018
DOI: 10.1016/J.CLAE.2017.10.004
Abstract: To investigate characteristics of the eyelid margins, meibomian glands and the tear film of contact lens wearers, and to determine whether these characteristics were related to symptoms of contact lens discomfort. A cross sectional study was performed on thirty existing daily wear soft contact lens wearers (6 male 24 female) with median age of 23 years (range 18-41). Eyelid signs and tear film characteristics were evaluated during a single visit and subjects completed the contact lens and dry eye questionnaire (CLDEQ-8) to evaluate ocular discomfort. Based on the CLDEQ-8 responses, subjects were classified as symptomatic (n = 17) or asymptomatic (n = 13). Grades of foam at meibomian gland orifices (3 ± 1), expressibility (2 ± 1) and quality of secretions (2 ± 1), tear evaporation rate with (112 ± 54 g/m Morphological irregularities of the meibomian glands and alterations to tear film secretions that affect tear evaporative dynamics were associated with symptoms of discomfort amongst the symptomatic lens wearers.
Publisher: Cold Spring Harbor Laboratory
Date: 29-10-2021
DOI: 10.1101/2021.10.27.466182
Abstract: The urban population spends up to 90% of their time indoors. The indoor environment harbours a erse microbial population including viruses, bacteria, and fungi. Pathogens present in the indoor environment can be transmitted to humans through aerosols. This study evaluated the efficacy of an antimicrobial gel containing a mix of essential oils against aerosols of bacteria, fungi, and coronavirus. The antimicrobial gel was allowed to vapourize inside a glass chamber for 10 or 20 minutes. Microbial aerosols of Escerichia coli, Aspergillus flavus spores or murine hepatitis virus MHV 1, a surrogate of SARS CoV-2 was passed through the gel vapours and then collected on a 6-stage Andersen s ler. The number of viable microbes present in the aerosols collected in the different stages were enumerated and compared to number of viable microbes in control microbial aerosols that were not exposed to the gel vapours. Vaporizing the antimicrobial gel for 10 and 20 minutes resulted in a 48% (p = 0.002 Vs. control) and 53% (p = 0.001 Vs. control) reduction in the number of MHV-1 in the aerosols, respectively. The antimicrobial gel vaporised for 10 minutes, reduced the number of viable E. coli by 51% (p = 0.032 Vs. control) and Aspergillus flavus spores by 72% (p=0.008 Vs. control) in the aerosols. The antimicrobial gel may be able to reduce aerosol transmission of microbes.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 08-2012
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 11-2017
Publisher: MDPI AG
Date: 03-10-2021
DOI: 10.3390/ANTIBIOTICS10101203
Abstract: Staphylococcus aureus is a frequent cause of ocular surface infections worldwide. Of these surface infections, those involving the cornea (microbial keratitis) are most sight-threatening. S. aureus can also cause conjunctivitis and contact lens-related non-infectious corneal infiltrative events (niCIE). The aim of this study was to determine the rates of resistance of S. aureus isolates to antibiotics and disinfecting solutions from these different ocular surface conditions. In total, 63 S. aureus strains from the USA and Australia were evaluated 14 were from niCIE, 26 from conjunctivitis, and 23 from microbial keratitis (MK). The minimum inhibitory (MIC) and minimum bactericidal concentrations (MBC) of all the strains to ciprofloxacin, ceftazidime, oxacillin, gentamicin, vancomycin, chlor henicol, azithromycin, and polymyxin B were determined. The MIC and MBC of the niCIE strains to contact lens multipurpose disinfectant solutions (MPDSs) was determined. All isolates were susceptible to vancomycin (100%). The susceptibility to other antibiotics decreased in the following order: gentamicin (98%), chlor henicol (76%), oxacillin (74%), ciprofloxacin (46%), ceftazidime (11%), azithromycin (8%), and polymyxin B (8%). In total, 87% of all the isolates were multidrug resistant and 17% of the isolates from microbial keratitis were extensively drug resistant. The microbial keratitis strains from Australia were usually susceptible to ciprofloxacin (57% vs. 11% p = 0.04) and oxacillin (93% vs. 11% p = 0.02) compared to microbial keratitis isolates from the USA. Microbial keratitis isolates from the USA were less susceptible (55%) to chlor henicol compared to conjunctivitis strains (95% p = 0.01). Similarly, 75% of conjunctivitis strains from Australia were susceptible to chlor henicol compared to 14% of microbial keratitis strains (p = 0.04). Most (93%) strains isolated from contact lens wearers were killed in 100% MPDS, except S. aureus 27. OPTI-FREE PureMoist was the most active MPDS against all strains with 35% of strains having an MIC ≤ 11.36%. There was a significant difference in susceptibility between OPTI-FREE PureMoist and Biotrue (p = 0.02). S. aureus non-infectious CIE strains were more susceptible to antibiotics than conjunctivitis strains and conjunctivitis strains were more susceptible than microbial keratitis strains. Microbial keratitis strains from Australia (isolated between 2006 and 2018) were more susceptible to antibiotics in comparison with microbial keratitis strains from the USA (isolated in 2004). Most of the strains were multidrug-resistant. There was variability in the susceptibility of contact lens isolates to MPDSs with one S. aureus strain, S. aureus 27, isolated from niCIE, in Australia in 1997 being highly resistant to all four MPDSs and three different types of antibiotics. Knowledge of the rates of resistance to antibiotics in different conditions and regions could help guide treatment of these diseases.
Publisher: MDPI AG
Date: 15-03-2022
DOI: 10.3390/ANTIBIOTICS11030393
Abstract: Transmission of pathogens present in the indoor air can occur through aerosols. This study evaluated the efficacy of an evaporated mix of essential oils to reduce the numbers of culturable aerosolized coronavirus, bacterium and fungus. The essential oil-containing gel was allowed to vaporize inside a glass chamber for 10 or 20 min. Aerosols of a surrogate of SARS-CoV-2, murine hepatitis coronavirus MHV-1, Escherichia coli or Aspergillus flavus spores were produced using a collision nebuliser and passed through the essential oil vapours, then collected on a six-stage Andersen s ler. The six-stages of the impact s ler capture aerosols in sizes ranging from 7 to 0.65 µm. The number of culturable microbes present in the aerosols collected in the different stages were enumerated and compared to the number of culturable microbes in control microbial aerosols that were not exposed to the evaporated essential oils. After 10 and 20 min evaporation, the essential oils reduced the numbers of culturable aerosolized coronavirus by 48% (log10 reduction = 0.3 p = 0.002 vs. control) and 53% (log10 reduction = 0.3 p = 0.001 vs. control), respectively. The essential oils vaporised for 10 min, reduced the number of viable E. coli by 51% (log10 reduction = 0.3 p = 0.032 vs. control). The Aspergillus flavus spores were mostly observed in the larger aerosols (7.00 µm to 2.10 µm) and the essential oils vaporised for 10 min reduced the number of viable spores by 72% (log10 reduction = 0.6 p = 0.008 vs. control). The vapours produced by a gel containing naturally occurring essential oils were able to significantly reduce the viable numbers of aerosolized coronavirus, bacteria and fungal spores. The antimicrobial gel containing the essential oils may be able to reduce aerosol transmission of microbes when used in domestic and workplace settings.
Publisher: Elsevier BV
Date: 11-2017
Publisher: eLife Sciences Publications, Ltd
Date: 20-01-2023
DOI: 10.7554/ELIFE.78089
Abstract: Against a backdrop of widespread global transmission, a number of countries have successfully brought large outbreaks of COVID-19 under control and maintained near-elimination status. A key element of epidemic response is the tracking of disease transmissibility in near real-time. During major outbreaks, the effective reproduction number can be estimated from a time-series of case, hospitalisation or death counts. In low or zero incidence settings, knowing the potential for the virus to spread is a response priority. Absence of case data means that this potential cannot be estimated directly. We present a semi-mechanistic modelling framework that draws on time-series of both behavioural data and case data (when disease activity is present) to estimate the transmissibility of SARS-CoV-2 from periods of high to low – or zero – case incidence, with a coherent transition in interpretation across the changing epidemiological situations. Of note, during periods of epidemic activity, our analysis recovers the effective reproduction number, while during periods of low – or zero – case incidence, it provides an estimate of transmission risk. This enables tracking and planning of progress towards the control of large outbreaks, maintenance of virus suppression, and monitoring the risk posed by re-introduction of the virus. We demonstrate the value of our methods by reporting on their use throughout 2020 in Australia, where they have become a central component of the national COVID-19 response.
Publisher: Elsevier BV
Date: 08-2020
DOI: 10.1016/J.CLAE.2019.11.004
Abstract: This study investigated the efficacy of pre-conditioning lens cases on bacterial biofilm formation and removal. Silver impregnated (MicroBlock / ProGuard™ & i-Clean) and control storage cases were pre-conditioned for 24 h with their respective multipurpose solutions (MPDSs). Cases were then inoculated with 2 ml of 10 Pre-conditioning the MicroBlock / ProGuard™ cases with MPDS significantly reduced biofilm formation (-1.1 log Pre-conditioning of silver-impregnated ProGuard™ lens cases inhibited initial bacterial biofilm formation. Synergi MPDS was more effective than AQuify MPDS in removing bacterial biofilm in silver impregnated cases and tissue-wiping significantly improved biofilm removal.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 02-2013
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 05-2021
DOI: 10.1097/OPX.0000000000001693
Abstract: The results of this study demonstrate that Smart Touch Technology packaging, which is designed to reduce and simplify contact lens handling before insertion, is effective in reducing the frequency of bacterial contamination of the back surface of contact lenses after short-term wear. The purpose of this study was to investigate the effect of lens packaging type, chelating agent, and finger contamination on microbial contamination on the back surface of worn soft contact lenses. Twenty-five subjects completed each contralateral lens wear comparison in this randomized study: Smart Touch Technology versus conventional blister packaging for (1) silicone hydrogel lenses with ethylenediaminetetraacetic acid (EDTA) and (2) hydrogel lenses without EDTA in the packaging, and (3) silicone hydrogel lenses without EDTA versus hydrogel lenses with EDTA both in Smart Touch Technology packaging. Participants washed hands, underwent finger swabs, and inserted the lenses. After 45 minutes, lenses were removed aseptically and the posterior lens surfaces cultured. Thirty-eight subjects (average age, 30.9 ± 12.5 years) participated in this study. Overall, the level of back surface contamination was low for both lens materials, ranging from 0 to 43 colony-forming unit (CFU)/lens for the silicone hydrogel and 0 to 17 CFU/lens for the hydrogel lenses. The proportion of lenses with zero back surface contamination ranged from 16 to 64% for silicone hydrogel lenses and 28 to 64% for hydrogel lenses. Contact lenses from conventional packaging containing EDTA had 3.38 times increased risk (95% confidence interval [CI], 1.02 to 11.11 P = .05) of contamination being present compared with lenses from Smart Touch packaging with EDTA. Contact lenses from conventional packaging without EDTA had 3.4 times increased risk (95% CI, 1.02 to 11.36 P = .05) of contamination being present compared with Smart Touch packaging without EDTA, and silicone hydrogel lenses had a 6.28 times increased risk (95% CI, 1.65 to 23.81 P = .007) of contamination being present compared with hydrogels. The median (interquartile range) number of bacteria isolated from fingers used to perform lens insertion after handwashing but before lens insertion was not significantly different between the silicone hydrogel and hydrogel lenses (63.7 [204.2] vs. 59 [84.5], P = .09). Finger contamination was not significantly associated with lens contamination in the presence or absence of EDTA. Smart Touch Technology packaging was effective in reducing the proportion of contaminated lenses. Although silicone hydrogel lenses were more likely to be contaminated, the presence of EDTA ameliorated this effect. Finger contamination was not associated with lens contamination.
Publisher: Springer Science and Business Media LLC
Date: 18-08-2015
Abstract: Measures of clinical incidence are necessary to help estimate the burden of a disease. Incidence is a metric not commonly measured in malariology because the longitudinal surveys required are costly and labour intensive. This database is an effort to collate published incidence records obtained using active case detection for Plasmodium falciparum and Plasmodium vivax malaria. The literature search methods, data abstraction procedures and data processing procedures are described here. A total of 1,680 spatio-temporally unique incidence records were collected for the database: 1,187 for P. falciparum and 493 for P. vivax . These data were gathered to model the relationship between clinical incidence and prevalence of infection and can be used for a variety of modelling exercises including the assessment of change in disease burden in relation to age and control interventions. The subset of data that have been used for such modelling exercises are described and identified.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 05-2008
Publisher: Public Library of Science (PLoS)
Date: 28-09-2018
Publisher: MDPI AG
Date: 12-09-2023
Publisher: Elsevier BV
Date: 07-2010
Publisher: Association for Research in Vision and Ophthalmology (ARVO)
Date: 2010
DOI: 10.1167/IOVS.09-4068
Abstract: One strategy to minimize bacteria-associated adverse responses such as microbial keratitis, contact lens-induced acute red eye (CLARE), and contact lens induced peripheral ulcers (CLPUs) that occur with contact lens wear is the development of an antimicrobial or antiadhesive contact lens. Cationic peptides represent a novel approach for the development of antimicrobial lenses. A novel cationic peptide, melimine, was covalently incorporated into silicone hydrogel lenses. Confirmation tests to determine the presence of peptide and anti-microbial activity were performed. Cationic lenses were then tested for their ability to prevent CLPU in the Staphylococcus aureus rabbit model and CLARE in the Pseudomonas aeruginosa guinea pig model. In the rabbit model of CLPU, melimine-coated lenses resulted in significant reductions in ocular symptom scores and in the extent of corneal infiltration (P < 0.05). Evaluation of the performance of melimine lenses in the CLARE model showed significant improvement in all ocular response parameters measured, including the percentage of eyes with corneal infiltrates, compared with those observed in the eyes fitted with the control lens (P < or = 0.05). Cationic coating of contact lenses with the peptide melimine may represent a novel method of prevention of bacterial growth on contact lenses and consequently result in reduction of the incidence and severity of adverse responses due to Gram-positive and -negative bacteria during lens wear.
Publisher: MDPI AG
Date: 15-11-2022
DOI: 10.3390/PATHOGENS11111354
Abstract: Staphylococcus aureus (S. aureus) is a frequent cause of eye infections with some isolates exhibiting increased antimicrobial resistance to commonly prescribed antibiotics. The increasing resistance of ocular S. aureus to ciprofloxacin is a serious concern as it is a commonly used as a first line antibiotic to treat S. aureus keratitis. This study aimed to analyse genetic mutations in the genomes of 25 S. aureus isolates from infections or non-infectious ocular conditions from the USA and Australia and their relationship to ciprofloxacin resistance. Overall, 14/25 isolates were phenotypically resistant to ciprofloxacin. All isolates were analyzed for mutations in their quinolone resistance-determining regions (QRDRs) and efflux pump genes. Of the fourteen resistant isolates, 9/14 had ciprofloxacin resistance mutations within their QRDRs, at codons 80 or 84 within the parC subunit and codon 84 within the gyrA subunit of DNA gyrase. The highest resistance (MIC = 2560 μg/mL) was associated with two SNPs in both gyrA and parC. Other resistant isolates (3/14) had mutations within norB. Mutations in genes of other efflux pumps and their regulator (norA, norC, mepA, mdeA, sepA, sdrM, mepR, arlR, and arlS) or the DNA mismatch repair (MMR) system (mutL and mutS) were not associated with increased resistance to ciprofloxacin. The functional mutations associated with ciprofloxacin resistance in QRDRs (gyrA and parC) and norB suggests that these are the most common reasons for ciprofloxacin resistance in ocular isolates. Novel SNPs of gyrA Glu-88-Leu, Asn-860-Thr and Thr-845-Ala and IIe-855-Met, identified in this study, need further gene knock out/in studies to better understand their effect on ciprofloxacin resistance.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 11-2018
DOI: 10.1097/OPX.0000000000001290
Abstract: Early diagnosis of clinical markers of contact lens discomfort can help clinicians set realistic expectations and monitor and provide prophylactic management for contact lens wearers. The purpose of this study was to evaluate the potential of eyelid- and tear film–related clinical markers to be used as predictive factors for diagnosing discomfort in contact lens wearers. A cross-sectional study was performed on 30 contact lens wearers (6 male, 24 female) with median age of 23 years (range, 18 to 41 years). Eyelid signs and tear film characteristics were evaluated during a single visit, and subjects completed the Contact Lens Dry Eye Questionnaire to evaluate ocular discomfort. Area under the curve (AUC) statistics and sensitivity and specificity values from receiver operating characteristic curves were analyzed to evaluate the predictive potential of clinical signs in discriminating symptoms of contact lens discomfort. The presence of foam at meibomian gland orifices (AUC, 0.944 P .05 sensitivity .7), meibomian gland secretion volume (AUC, 0.935 P .05 sensitivity .7), quality (AUC, 0.969 P .05 sensitivity .7), and expressibility (AUC, 0.933 P .05 sensitivity .7) were significant and strong predictors of discomfort in lens wear. Tear evaporation rates with (AUC, 0.779 P .05 sensitivity .7) or without contact lenses (AUC, 0.788 P .05 sensitivity .7), palpebral conjunctival roughness (AUC, 0.859 P .05 sensitivity .7), palpebral conjunctival staining (AUC, 0.817 P .05 sensitivity .7), palpebral conjunctival hyperemia (AUC, 0.746 P .05 sensitivity .7), meibomian gland orifice capping (AUC, 0.873 P .05 sensitivity .7), pouting (AUC, 0.891 P .05 sensitivity .7), and lid-parallel conjunctival folds (AUC, 0.770 P .05 sensitivity .7) were other acceptable discriminators of symptoms of discomfort during contact lens wear. An equation was developed to identify symptomatic from asymptomatic lens wearers based on the significant predictors: Symptom discriminant function score = 3.378 (meibomian gland secretion grade) + 0.224 (meibomian gland morphology grade) + 0.61 (tear evaporation rate without contact lenses) + 0.439 (lid-parallel conjunctival folds grade) − 0.346 (palpebral conjunctival health grade) − 4.625. This study demonstrated that clinical signs related to meibomian gland secretions and morphology, tear evaporation, lid-parallel conjunctival folds, and palpebral conjunctival health may successfully predict symptoms of discomfort in contact lens wearers.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 09-2017
Publisher: Elsevier BV
Date: 04-2021
Publisher: Informa UK Limited
Date: 03-2018
DOI: 10.1111/CXO.12621
Abstract: Treatment of Pseudomonas aeruginosa eye infections often becomes a challenge due to the ability of this bacterium to be resistant to antibiotics via intrinsic and acquired mechanisms. Transfer of resistance due to interchangeable genetic elements is an important mechanism for the rapid transfer of antibiotic resistance in this pathogen. As a result, drug-resistant strains are becoming increasingly prevalent worldwide. This review systematically analyses data from recent publications to describe the global prevalence and antibiotic sensitivity of ocular P. aeruginosa. Thirty-seven studies were selected for review from PubMed-based searches using the criteria 'microbial keratitis OR eye infection AND Pseudomonas aeruginosa AND antibiotic resistance' and limiting to papers from 2011 onward, to demonstrate the antibiotic resistance from isolates from around the world. Subsequently, we reviewed the ways in which P. aeruginosa can become resistant to antibiotics. Both the rate of isolation of bacteria in general (79 per cent of cases), and prevalence of P. aeruginosa (68 per cent of all isolates) were highest in contact lens-related microbial keratitis. The average resistance rate to common ocular antibiotics such as ciprofloxacin (9 per cent), gentamicin (22 per cent) and ceftazidime (13 per cent) remained relatively low. However, there were large variations in resistance rates reported in studies from different countries, for ex le resistance to ciprofloxacin reached up to 33 per cent. We next reviewed the types of mobile genetic elements (MGEs) such as plasmids, integrons and transposons that are frequently associated with drug resistance in P. aeruginosa. MGEs are important for the transmission of resistance to beta-lactams and aminoglycosides and recently have been shown to be potential factors for the transmission of fluoroquinolone resistance. Studies on the molecular mechanisms of resistance transfer in ocular P. aeruginosa have begun to be reported and will provide valuable information on the emergence of new antibiotic resistance and potential to treat resistant strains.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 11-2012
Publisher: Public Library of Science (PLoS)
Date: 15-04-2019
Publisher: Elsevier BV
Date: 02-2021
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 07-2008
Publisher: Springer Science and Business Media LLC
Date: 07-05-2015
Publisher: Oxford University Press (OUP)
Date: 13-03-2018
DOI: 10.1093/JAC/DKY073
Publisher: Springer Science and Business Media LLC
Date: 13-02-2007
DOI: 10.1007/S10456-007-9063-3
Abstract: Corneal vascularisation is a potentially devastating occurrence that can cause blindness. Currently, treatments for this condition are limited. In these studies, we have investigated a novel inhibitor of angiogenesis, 12-methyl tetradecanoic acid (12-MTA), to treat corneal vascularisation in mouse models of corneal alkali injury and corneal Pseudomonas aeruginosa infection. The effectiveness of 12-MTA was compared to treatment with dexamethasone. 12-MTA was found to be at least as effective as dexamethasone in reducing the angiogenesis that occurs following alkali injury or P. aeruginosa infection of the cornea. The major effect of both 12-MTA and dexamethasone in these models was to reduce the linear incursion of new blood vessels into the central cornea. A significantly better result was obtained at 14 days post-alkali injury when treatment was not delayed. A major advantage of treatment of alkali injury with 12-MTA compared to that with dexamethasone was the finding that there was a 5-fold less level of PMN infiltration and no persistent epithelial defects in corneas treated with 12-MTA compared to 50% of those treated with dexamethasone. Our studies indicate that 12-MTA may provide clinically significant advantages over conventional steroids for the treatment of vessel growth in the cornea.
Publisher: Informa UK Limited
Date: 30-09-2021
Publisher: Wiley
Date: 30-08-2021
Abstract: Light‐level geolocators are popular bio‐logging tools, with advantageous sizes, longevity and affordability. Biologists tracking seabirds often presume geolocator spatial accuracies between 186 and 202 km from previously innovative, yet taxonomically, spatially and computationally limited, studies. Using recently developed methods, we investigated whether assumed uncertainty norms held across a larger‐scale, multispecies study. We field‐tested geolocator spatial accuracy by synchronously deploying these with GPS loggers on scores of seabirds across five species and 11 Mediterranean Sea, east Atlantic and south Pacific breeding colonies. We first interpolated geolocations using the geolocation package FLightR without prior knowledge of GPS tracked routes. We likewise applied another package, probGLS , additionally testing whether sea‐surface temperatures could improve route accuracy. Geolocator spatial accuracy was lower than the ~200 km often assumed. probGL S produced the best accuracy (mean ± SD = 304 ± 413 km, n = 185 deployments) with 84.5% of GPS‐derived latitudes and 88.8% of longitudes falling within resulting uncertainty estimates. FLightR produced lower spatial accuracy (408 ± 473 km, n = 171 deployments) with 38.6% of GPS‐derived latitudes and 23.7% of longitudes within package‐specific uncertainty estimates. Expected inter‐twilight period (from GPS position and date) was the strongest predictor of accuracy, with increasingly equatorial solar profiles (i.e. closer temporally to equinoxes and/or spatially to the Equator) inducing more error. In iduals, species and geolocator model also significantly affected accuracy, while the impact of distance travelled between successive twilights depended on the geolocation package. Geolocation accuracy is not uniform among seabird species and can be considerably lower than assumed. In idual idiosyncrasies and spatiotemporal dynamics (i.e. shallower inter‐twilight shifts by date and latitude) mean that practitioners should exercise greater caution in interpreting geolocator data and avoid universal uncertainty estimates. We provide a function capable of estimating relative accuracy of positions based on geolocator‐observed inter‐twilight period.
Publisher: MDPI AG
Date: 11-12-2020
DOI: 10.3390/W12123493
Abstract: Acanthamoeba keratitis (AK) is a sight-threatening infection of the cornea, which is caused by soil and the waterborne protist Acanthamoeba spp. AK most commonly occurs during contact lens (CL) wear. Risk factors for AK have been linked to non-optimal lens hygiene practices and Acanthamoeba contamination of domestic water. This study investigated the prevalence of Acanthamoeba species in domestic showers in the greater Sydney region, as well as the perception of water contamination of CL as being a risk factor for AK among previous AK patients and their family and friends. S les from four locations of 13 participants’ shower areas were cultured and Acanthamoeba 18S rRNA was lified by PCR, followed by sequencing. Twenty-six responses were received to the online questionnaire. Fifteen water s les (29%, 15/52) contained amoeba that were morphologically classified as Acanthamoeba spp. PCR lification confirmed the presence of Acanthamoeba spp. in four s les (8%, 4/52). Three isolates belonged to the T4, and one isolate to the T3 genotype. On the questionnaire survey, 96% (25/26) of respondents believed that water contamination was likely to be a risk factor for Acanthamoeba keratitis and 58% rated showering with CL as ‘extremely likely’ to be a risk factor for AK. Acanthamoeba pathogenic genotypes (T3 and T4) in the domestic bathroom water suggest that clinicians should remain vigilant in educating CL wearers about avoiding domestic water contamination of CL.
Publisher: Informa UK Limited
Date: 09-03-2022
DOI: 10.1080/08164622.2022.2040334
Abstract: Hand hygiene is important to reduce the spread of microbes in clinical settings. Hand sanitisers that last longer may be beneficial. Longevity of hand sanitisation products on fingers and hands may be important to help reduce microbial transmission. The current study evaluated the persistence of disinfection of three hand sanitisers. Initially the minimum inhibitory concentrations of the hand sanitisers were determined using strains of The minimum inhibitory concentration of an alcohol-based sanitiser (AS) was 10%, for the capric acid-based (CS) sanitiser was 70%, and for the quaternary ammonium-based (QS) sanitiser was < 10%. AS significantly reduced the number of microbes on fingers 10 minutes after hand washing (18.2 cfu/mL) compared to CS (59.7 cfu/mL p < 0.0001) or QS (64.5 cfu/mL p < 0.0001). Twenty minutes after use, microbes on fingers after AS (23 cfu/mL) or CS (16.7 cfu/mL) were significantly reduced compared to QS (72.2 cfu/mL p < 0.0001) and the numbers on fingers after CS was significantly less than after AS (p = 0.002). Four hours after use of any hand sanitiser, the number of microbes increased to near baseline levels. The reduction in bacterial numbers was not affected by the use of neutralisers in agar (48 ± 28% reduction with, 47 ± 49% reduction without p = 0.876). Hand sanitisers containing capric acid or alcohol out-performed one containing quaternary ammonium in the clinical trial and may help reduce the spread of microbes.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 08-2011
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 03-2022
Publisher: Elsevier BV
Date: 10-2021
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 09-2017
Start Date: 05-2018
End Date: 12-2022
Amount: $365,058.00
Funder: Australian Research Council
View Funded ActivityStart Date: 05-2019
End Date: 12-2023
Amount: $437,000.00
Funder: Australian Research Council
View Funded Activity