419 research outputs found
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Automation and validation of micronucleus detection in the 3D EpiDerm™ human reconstructed skin assay and correlation with 2D dose responses.
Recent restrictions on the testing of cosmetic ingredients in animals have resulted in the need to test the genotoxic potential of chemicals exclusively in vitro prior to licensing. However, as current in vitro tests produce some misleading positive results, sole reliance on such tests could prevent some chemicals with safe or beneficial exposure levels from being marketed. The 3D human reconstructed skin micronucleus (RSMN) assay is a promising new in vitro approach designed to assess genotoxicity of dermally applied compounds. The assay utilises a highly differentiated in vitro model of the human epidermis. For the first time, we have applied automated micronucleus detection to this assay using MetaSystems Metafer Slide Scanning Platform (Metafer), demonstrating concordance with manual scoring. The RSMN assay's fixation protocol was found to be compatible with the Metafer, providing a considerably shorter alternative to the recommended Metafer protocol. Lowest observed genotoxic effect levels (LOGELs) were observed for mitomycin-C at 4.8 µg/ml and methyl methanesulfonate (MMS) at 1750 µg/ml when applied topically to the skin surface. In-medium dosing with MMS produced a LOGEL of 20 µg/ml, which was very similar to the topical LOGEL when considering the total mass of MMS added. Comparisons between 3D medium and 2D LOGELs resulted in a 7-fold difference in total mass of MMS applied to each system, suggesting a protective function of the 3D microarchitecture. Interestingly, hydrogen peroxide (H2O2), a positive clastogen in 2D systems, tested negative in this assay. A non-genotoxic carcinogen, methyl carbamate, produced negative results, as expected. We also demonstrated expression of the DNA repair protein N-methylpurine-DNA glycosylase in EpiDerm™. Our preliminary validation here demonstrates that the RSMN assay may be a valuable follow-up to the current in vitro test battery, and together with its automation, could contribute to minimising unnecessary in vivo tests by reducing in vitro misleading positives
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Efficacy and Safety of Intensified vs Standard Prophylactic Anticoagulation Therapy in Patients Hospitalized With Coronavirus Disease 2019: Updated Systematic Review and Meta-analysis.
Evaluation of the automated MicroFlow® and Metafer™ platforms for high-throughput micronucleus scoring and dose response analysis in human lymphoblastoid TK6 cells
Evolution of Th2 responses : Characterization of IL-4/13 in sea bass (Dicentrarchus labrax L.) and studies of expression and biological activity
Acknowledgements This research was funded by the European Commission under the 7th Framework Programme for Research and Technological Development (FP7) of the European Union (Grant Agreement 311993 TARGETFISH). T.W. received funding from the MASTS pooling initiative (The Marine Alliance for Science and Technology for Scotland). MASTS is funded by the Scottish Funding Council (grant reference number HR09011) and contributing institutions.Peer reviewedPublisher PD
Re: Gi et al. 2018, In vivo positive mutagenicity of 1,4-dioxane and quantitative analysis of its mutagenicity and carcinogenicity in rats, Archives of Toxicology 92:3207–3221
Intra-gastric balloon as an adjunct to lifestyle support in severely obese adolescents; Impact on weight, physical activity, cardio-respiratory fitness and psychosocial wellbeing.
BACKGROUND: Severe adolescent obesity (BMI>99.6th centile) is a significant public health challenge. Current non-invasive treatments, including community-based lifestyle interventions, are often of limited effectiveness in this population, with NICE guidelines suggesting the use of bariatric surgery as the last line of treatment (NICE, 2013). Health professionals are understandably reluctant to commission bariatric surgery and as an alternative, the use of an intra-gastric balloon as an adjunct to a lifestyle programme might offer a reversible, potentially safer and less invasive option.
OBJECTIVES: Explore the use of an intra-gastric balloon as an adjunct to a lifestyle support programme, to promote weight loss in severely obese adolescents. Outcomes included Weight loss, Waist and Hip measurements, psychosocial outcomes including health related quality of life and physical self-perceptions, physical activity and cardiorespiratory fitness.
METHOD: Non-randomised pilot study. Results: 12 severely obese adolescents (5 males, 7 females; mean age 15yrs; BMI >3.5 s.d.; puberty stage 4 or more) and their families were recruited. Mean weight loss at 12 months (n=9) was 3.05 kg±14.69; d=0.002, P=0.550, and a BMI Z-score (n=12) change of 0.2 s.d.; d=0.7, P=0.002 was observed at 6 months with a large effect, but was not sustained at 12 months (mean change 0.1 s.d.; d=0.3, P=0.146 ) At 24 months (n=10) there was a weight gain from baseline of +9.9 kg±1.21 (d=0.4; P=0.433). Adolescent and parent HRQoL scores exceeded the minimal clinical important difference between baseline and 12 months for all domains but showed some decline at 24 months.
CONCLUSION: An intra-gastric balloon as an adjunct to a lifestyle support programme represents a safe and well tolerated treatment approach in severely obese adolescents, with short-term effects on weight change. Improvements in psychosocial health, physical activity and cardiorespiratory fitness were maintained at 12 months, with varying results at 24 months
CT694 and pgp3 as Serological Tools for Monitoring Trachoma Programs.
Defining endpoints for trachoma programs can be a challenge as clinical signs of infection may persist in the absence of detectable bacteria. Antibody-based tests may provide an alternative testing strategy for surveillance during terminal phases of the program. Antibody-based assays, in particular ELISAs, have been shown to be useful to document C. trachomatis genital infections, but have not been explored extensively for ocular C. trachomatis infections. An antibody-based multiplex assay was used to test two C. trachomatis antigens, pgp3 and CT694, for detection of trachoma antibodies in bloodspots from Tanzanian children (n = 160) collected after multiple rounds of mass azithromycin treatment. Using samples from C. trachomatis-positive (by PCR) children from Tanzania (n = 11) and control sera from a non-endemic group of U.S. children (n = 122), IgG responses to both pgp3 and CT694 were determined to be 91% sensitive and 98% specific. Antibody responses of Tanzanian children were analyzed with regard to clinical trachoma, PCR positivity, and age. In general, children with more intense ocular pathology (TF/TI = 2 or most severe) had a higher median antibody response to pgp3 (p = 0.0041) and CT694 (p = 0.0282) than those with normal exams (TF/TI = 0). However, 44% of children with no ocular pathology tested positive for antibody, suggesting prior infection. The median titer of antibody responses for children less than three years of age was significantly lower than those of older children. (p<0.0001 for both antigens). The antibody-based multiplex assay is a sensitive and specific additional tool for evaluating trachoma transmission. The assay can also be expanded to include antigens representing different diseases, allowing for a robust assay for monitoring across NTD programs
Other-Sex Friendships in Late Adolescence: Risky Associations for Substance Use and Sexual Debut?
Adolescents’ friendships with other-sex peers serve important developmental functions, but they may also facilitate engagement in problem behavior. This study examines the unique contributions of other-sex friendships and friends’ behavior to alcohol use, smoking, and initiation of sexual intercourse among late adolescent girls and boys. A total of 320 adolescents (53% girls; 33% racial/ethnic minorities) provided sociometric nominations of friendships annually in grades 10–12. Friendship networks were derived using social network analysis in each grade. Adolescents and their friends also reported on their alcohol use, smoking, and sexual debut at each assessment. After controlling for demographics, previous problem behavior, and friends’ behavior, other-sex friendships in 10th grade were associated with initiation of smoking among girls over the following year, and other-sex friendships in 11th grade were linked with lower levels of subsequent alcohol use among boys. Additionally, friends’ smoking and sexual experience in 10th grade predicted the same behaviors for all adolescents over the following year. Other-sex friendships thus appear to serve as a risk context for adolescent girls’ smoking and a protective context for adolescent boys’ drinking. Promoting mixed-gender activities and friendships among older high school students may be helpful in reducing males’ alcohol use, but may need to incorporate additional components to prevent increases in females’ smoking
Incentive payments to general practitioners aimed at increasing opportunistic testing of young women for chlamydia: a pilot cluster randomised controlled trial
<p>Abstract</p> <p>Background</p> <p>Financial incentives have been used for many years internationally to improve quality of care in general practice. The aim of this pilot study was to determine if offering general practitioners (GP) a small incentive payment per test would increase chlamydia testing in women aged 16 to 24 years, attending general practice.</p> <p>Methods</p> <p>General practice clinics (n = 12) across Victoria, Australia, were cluster randomized to receive either a $AUD5 payment per chlamydia test or no payment for testing 16 to 24 year old women for chlamydia. Data were collected on the number of chlamydia tests and patient consultations undertaken by each GP over two time periods: 12 month pre-trial and 6 month trial period. The impact of the intervention was assessed using a mixed effects logistic regression model, accommodating for clustering at GP level.</p> <p>Results</p> <p>Testing increased from 6.2% (95% CI: 4.2, 8.4) to 8.8% (95% CI: 4.8, 13.0) (p = 0.1) in the control group and from 11.5% (95% CI: 4.6, 18.5) to 13.4% (95% CI: 9.5, 17.5) (p = 0.4) in the intervention group. Overall, the intervention did not result in a significant increase in chlamydia testing in general practice. The odds ratio for an increase in testing in the intervention group compared to the control group was 0.9 (95% CI: 0.6, 1.2). Major barriers to increased chlamydia testing reported by GPs included a lack of time, difficulty in remembering to offer testing and a lack of patient awareness around testing.</p> <p>Conclusions</p> <p>A small financial incentive alone did not increase chlamydia testing among young women attending general practice. It is possible small incentive payments in conjunction with reminder and feedback systems may be effective, as may higher financial incentive payments. Further research is required to determine if financial incentives can increase testing in Australian general practice, the type and level of financial scheme required and whether incentives needs to be part of a multi-faceted package.</p> <p>Trial Registration</p> <p>Australian New Zealand Clinical Trial Registry ACTRN12608000499381.</p
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