257 research outputs found
Selected histone deacetylase inhibitors reverse the frataxin transcriptional defect in a novel Friedreich\u27s ataxia induced pluripotent stem cell-derived neuronal reporter system
Friedreich\u27s ataxia (FRDA) is a neurodegenerative disorder caused by the expansion of guanine-adenine-adenine repeats within the first intron of the frataxin
The epidemiology of HIV among young people in sub-Saharan Africa: know your local epidemic and its implications for prevention.
BACKGROUND: Broad patterns of HIV epidemiology are frequently used to design generic HIV programs in sub-Saharan Africa. METHODS: We reviewed the epidemiology of HIV among young people in sub-Saharan Africa, and explored the unique dynamics of infection in its different regions. RESULTS: In 2009, HIV prevalence among youth in sub-Saharan Africa was an estimated 1.4% in males and 3.4% in females, but these values mask wide variation at regional and national levels. Within countries there are further major differences in HIV prevalence, such as by sex, urban/rural location, economic status, education, or ethnic group. Within this highly nuanced context, HIV prevention programs targeting youth must consider both where new infections are occurring and where they are coming from. CONCLUSIONS: Given the epidemiology, one-size-fits-all HIV prevention programs are usually inappropriate at regional and national levels. Consideration of local context and risk associated with life transitions, such as leaving school or getting married, is imperative to successful programming for young people
HIV self-testing services for female sex workers, Malawi and Zimbabwe
OBJECTIVE: To present findings from implementation and scale-up of human immunodeficiency virus (HIV) self-testing programmes for female sex workers in Malawi and Zimbabwe, 2013-2018. METHODS: In Zimbabwe, we carried out formative research to assess the acceptability and accuracy of HIV self-testing. During implementation we evaluated sex workers' preferences for, and feasibility of, distribution of test kits before the programme was scaled-up. In Malawi, we conducted a rapid ethnographic assessment to explore the context and needs of female sex workers and resources available, leading to a workshop to define the distribution approach for test kits. Once distribution was implemented, we conducted a process evaluation and established a system for monitoring social harm. FINDINGS: In Zimbabwe, female sex workers were able to accurately self-test. The preference study helped to refine systems for national scale-up through existing services for female sex workers. The qualitative data helped to identify additional distribution strategies and mediate potential social harm to women. In Malawi, peer distribution of test kits was the preferred strategy. We identified some incidents of social harm among peer distributors and female sex workers, as well as supply-side barriers to implementation which hindered uptake of testing. CONCLUSION: Involving female sex workers in planning and ongoing implementation of HIV self-testing is essential, along with strategies to mitigate potential harm. Optimal strategies for distribution and post-test support are context-specific and need to consider existing support for female sex workers and levels of trust and cohesion within their communities
Enhancing national prevention and treatment services for sex workers in Zimbabwe: a process evaluation of the SAPPH-IRe trial.
Targeted HIV interventions for female sex workers (FSW) combine biomedical technologies, behavioural change and community mobilization with the aim of empowering FSW and improving prevention and treatment. Understanding how to deliver combined interventions most effectively in sub-Saharan Africa is critical to the HIV response. The Sisters' Antiretroviral Programme for Prevention of HIV: an Integrated Response (SAPPH-Ire) randomized controlled trial in Zimbabwe tested an intervention to improve FSW engagement with HIV services. After 2 years, results of the trial showed no significant difference between study arms in proportion of FSW with HIV viral load ≥1000 copies/ml as steep declines occurred in both. We present the results of a process evaluation aiming to track the intervention's implementation, assess its feasibility and accessibility, and situate trial results within the national HIV policy context. We conducted a mixed methods study using data from routine programme statistics, qualitative interviews with participants and respondent driven surveys. The intervention proved feasible to deliver and was acceptable to FSW and providers. Intervention clinics saw more new FSW (4082 vs 2754), performed over twice as many HIV tests (2606 vs 1151) and nearly double the number of women were diagnosed with HIV (1042 vs 546). Community mobilization meetings in intervention sites also attracted higher numbers. We identified some gaps in programme fidelity: offering pre-exposure prophylaxis took time to engage FSW, viral load monitoring was not performed, and ratio of peer educators to FSW was lower than intended. During the trial, reaching FSW with HIV testing and treatment became a national priority, leading to increasing attendance at both intervention and control clinics. Throughout Zimbabwe, antiretroviral therapy coverage improved and HIV-stigma declined. Zimbabwe's changing HIV policy context appeared to contribute to positive improvements across the HIV care continuum for all FSW over the course of the trial. More intense community-based interventions for FSW may be needed to make further gains
In vitro recellularization of decellularized bovine carotid arteries using human endothelial colony forming cells
Background: Many patients suffering from peripheral arterial disease (PAD) are dependent on bypass surgery. However, in some patients no suitable replacements (i.e. autologous or prosthetic bypass grafts) are available. Advances have been made to develop autologous tissue engineered vascular grafts (TEVG) using endothelial colony forming cells (ECFC) obtained by peripheral blood draw in large animal trials. Clinical translation of this technique, however, still requires additional data for usability of isolated ECFC from high cardiovascular risk patients. Bovine carotid arteries (BCA) were decellularized using a combined SDS (sodium dodecyl sulfate) -free mechanical-osmotic-enzymatic-detergent approach to show the feasibility of xenogenous vessel decellularization. Decellularized BCA chips were seeded with human ECFC, isolated from a high cardiovascular risk patient group, suffering from diabetes, hypertension and/or chronic renal failure. ECFC were cultured alone or in coculture with rat or human mesenchymal stromal cells (rMSC/hMSC). Decellularized BCA chips were evaluated for biochemical, histological and mechanical properties. Successful isolation of ECFC and recellularization capabilities were analyzed by histology.
Results: Decellularized BCA showed retained extracellular matrix (ECM) composition and mechanical properties upon cell removal. Isolation of ECFC from the intended target group was successfully performed (80% isolation efficiency). Isolated cells showed a typical ECFC-phenotype. Upon recellularization, co-seeding of patient-isolated ECFC with rMSC/hMSC and further incubation was successful for 14 (n = 9) and 23 (n = 5) days. Reendothelialization (rMSC) and partial reendothelialization (hMSC) was achieved. Seeded cells were CD31 and vWF positive, however, human cells were detectable for up to 14 days in xenogenic cell-culture only. Seeding of ECFC without rMSC was not successful.
Conclusion: Using our refined decellularization process we generated easily obtainable TEVG with retained ECM- and mechanical quality, serving as a platform to develop small-diameter (< 6 mm) TEVG. ECFC isolation from the cardiovascular risk target group is possible and sufficient. Survival of diabetic ECFC appears to be highly dependent on perivascular support by rMSC/hMSC under static conditions. ECFC survival was limited to 14 days post seeding
Effect of non-monetary incentives on uptake of couples’ counselling and testing among clients attending mobile HIV services in rural Zimbabwe: a cluster-randomised trial
Background
Couples' HIV testing and counselling (CHTC) is associated with greater engagement with HIV prevention and care than individual testing and is cost-effective, but uptake remains suboptimal. Initiating discussion of CHTC might result in distrust between partners. Offering incentives for CHTC could change the focus of the pre-test discussion. We aimed to determine the impact of incentives for CHTC on uptake of couples testing and HIV case diagnosis in rural Zimbabwe.
Methods
In this cluster-randomised trial, 68 rural communities (the clusters) in four districts receiving mobile HIV testing services were randomly assigned (1:1) to incentives for CHTC or not. Allocation was not masked to participants and researchers. Randomisation was stratified by district and proximity to a health facility. Within each stratum random permutation was done to allocate clusters to the study groups. In intervention communities, residents were informed that couples who tested together could select one of three grocery items worth US$1·50. Standard mobilisation for testing was done in comparison communities. The primary outcome was the proportion of individuals testing with a partner. Analysis was by intention to treat. 3 months after CHTC, couple-testers from four communities per group individually completed a telephone survey to evaluate any social harms resulting from incentives or CHTC. The effect of incentives on CHTC was estimated using logistic regression with random effects adjusting for clustering. The trial was registered with the Pan African Clinical Trial Registry, number PACTR201606001630356.
Findings
From May 26, 2015, to Jan 29, 2016, of 24 679 participants counselled with data recorded, 14 099 (57·1%) were in the intervention group and 10 580 (42·9%) in the comparison group. 7852 (55·7%) testers in the intervention group versus 1062 (10·0%) in the comparison group tested with a partner (adjusted odds ratio 13·5 [95% CI 10·5–17·4]). Among 427 (83·7%) of 510 eligible participants who completed the telephone survey, 11 (2·6%) reported that they were pressured or themselves pressured their partner to test together; none regretted couples' testing. Relationship unrest was reported by eight individuals (1·9%), although none attributed this to incentives.
Interpretation
Small non-monetary incentives, which are potentially scalable, were associated with significantly increased CHTC and HIV case diagnosis. Incentives did not increase social harms beyond the few typically encountered with CHTC without incentives. The intervention could help achieve UNAIDS 90-90-90 targets
Perfusion-Based Recellularization of Rat Livers with Islets of Langerhans
Purpose: Artificial organs might serve as alternative solutions for whole organ transplantation. Decellularization of a liver provides a non-immunogenic matrix with the advantage of three afferent systems, the portal vein, the hepatic artery and the bile duct. This study aims to evaluate the recellularization of rat livers with islets of Langerhans via the bile duct and the portal vein for the comparison of different perfusion routes.
Methods: Rat livers were decellularized in a pressure-controlled perfusion manner and repopulated with intact isolated islets of Langerhans via either the portal vein or the bile duct.
Results: Repopulation via the portal vein showed islet clusters stuck within the vascular system demonstrated by ellipsoid borders of thick reticular tissue around the islet cluster in Azan staining. After recellularization via the bile duct, islets were distributed close to the vessels within the parenchymal space and without a surrounding reticular layer. Large clusters of islets had a diameter of up to 1000 mu m without clear shapes.
Conclusion: We demonstrated the bile duct to be superior to the portal vein for repopulation of a decellularized rat liver with islets of Langerhans. This technique may serve as a bioengineering platform to generate an implantable and functional endocrine neo-pancreas and provide scaffolds with the anatomic benefit of three afferent systems to facilitate co-population of cells
The long-term impact of the MEMA kwa Vijana adolescent sexual and reproductive health intervention: effect of dose and time since intervention exposure.
BACKGROUND: Despite recent decreases in HIV incidence in many sub-Saharan African countries, there is little evidence that specific behavioural interventions have led to a reduction in HIV among young people. Further and wider-scale decreases in HIV require better understanding of when behaviour change occurs and why. The MEMA kwa Vijana adolescent sexual and reproductive health intervention has been implemented in rural Mwanza, Tanzania since 1999. A long-term evaluation in 2007/8 found that the intervention improved knowledge, attitudes to sex and some reported risk behaviours, but not HIV or HSV2 prevalence. The aim of this paper was to assess the differential impact of the intervention according to gender, age, marital status, number of years of exposure and time since last exposure to the intervention. METHODS: In 2007, a cross-sectional survey was conducted in the 20 trial communities among 13,814 young people (15-30 yrs) who had attended intervention or comparison schools between 1999 and 2002. Outcomes for which the intervention had an impact in 2001 or 2007 were included in this subgroup analysis. Data were analysed using cluster-level methods for stratified cluster-randomised trials, using interaction tests to determine if intervention impact differed by subgroup. RESULTS: Taking into account multiplicity of testing, concurrence with a priori hypotheses and consistency within the results no strong effect-modifiers emerged. Impact on pregnancy knowledge and reported attitudes to sex increased with years of exposure to high-quality intervention. CONCLUSIONS: The desirable long-term impact of the MEMA kwa Vijana intervention did not vary greatly according to the subgroups examined. This suggests that the intervention can have an impact on a broad cross-section of young people in rural Mwanza. TRIAL REGISTRATION: ClinicalTrials.gov NCT00248469
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