786 research outputs found

    Resurgence of HIV infection among men who have sex with men in Switzerland : mathematical modelling study

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    New HIV infections in men who have sex with men (MSM) have increased in Switzerland since 2000 despite combination antiretroviral therapy (cART). The objectives of this mathematical modelling study were: to describe the dynamics of the HIV epidemic in MSM in Switzerland using national data; to explore the effects of hypothetical prevention scenarios; and to conduct a multivariate sensitivity analysis. METHODOLOGY/PRINCIPAL FINDINGS: The model describes HIV transmission, progression and the effects of cART using differential equations. The model was fitted to Swiss HIV and AIDS surveillance data and twelve unknown parameters were estimated. Predicted numbers of diagnosed HIV infections and AIDS cases fitted the observed data well. By the end of 2010, an estimated 13.5% (95% CI 12.5, 14.6%) of all HIV-infected MSM were undiagnosed and accounted for 81.8% (95% CI 81.1, 82.4%) of new HIV infections. The transmission rate was at its lowest from 1995-1999, with a nadir of 46 incident HIV infections in 1999, but increased from 2000. The estimated number of new infections continued to increase to more than 250 in 2010, although the reproduction number was still below the epidemic threshold. Prevention scenarios included temporary reductions in risk behaviour, annual test and treat, and reduction in risk behaviour to levels observed earlier in the epidemic. These led to predicted reductions in new infections from 2 to 26% by 2020. Parameters related to disease progression and relative infectiousness at different HIV stages had the greatest influence on estimates of the net transmission rate. CONCLUSIONS/SIGNIFICANCE: The model outputs suggest that the increase in HIV transmission amongst MSM in Switzerland is the result of continuing risky sexual behaviour, particularly by those unaware of their infection status. Long term reductions in the incidence of HIV infection in MSM in Switzerland will require increased and sustained uptake of effective interventions

    Role of common human TRIM5α variants in HIV-1 disease progression

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    BACKGROUND: The retroviral restriction factor tripartite motif protein (TRIM)5α, is characterized by marked amino acid diversity among primates, including specific clusters of residues under positive selection. The identification of multiple non-synonymous changes in humans suggests that TRIM5α variants might be relevant to retroviral pathogenesis. Previous studies have shown that such variants are unlikely to modify susceptibility to HIV-1 infection, or the course of early infection. However, the longterm effect of carrying Trim5α variants on disease progression in individuals infected with HIV-1 has not previously been investigated. METHODS: In a cohort of 979 untreated individuals infected with HIV-1 with median follow up 3.2 years and 9,828 CD4 T cell measurements, we analysed common amino acid variations: H43Y, V112F, R136Q, G249D, and H419Y. The rate of CD4 T cell decline before treatment was used as the phenotype. In addition, we extended previous work on the in vitro susceptibility of purified donor CD4 T cells (n = 125) to HIV-1 infection, and on the susceptibility of HeLa cells that were stably transduced with the different TRIM5 variants. Haplotypes were analysed according to the most parsimonious evolutionary structure, where two main human TRIM5α groups can be defined according to the residue at amino acid 136. Humans present both Q136 and R136 at similar frequency, and additional TRIM5α amino acid variants are almost exclusively derived from R136-carrying haplotypes. RESULTS: We observed modest differences in disease progression for evolutionary branches carrying R136-derived haplotypes, and with the non-synonymous polymorphisms G249D and H419Y. In vitro analysis of susceptibility of donor CD4 T cells, and of the various transduced HeLa cell lines supported the absence of significant differential restriction of HIV-1 infection by the various huTRIM5α alleles. CONCLUSION: Common human variants of TRIM5α have no effect or modest effect on HIV-1 disease progression. These variants occur at sites conserved throughout evolution, and are remote from clusters of positive selection in the primate lineage. The evolutionary value of the substitutions remains unclear

    Migrating a Well-Established Longitudinal Cohort Database From Oracle SQL to Research Electronic Data Entry (REDCap): Data Management Research and Design Study

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    BACKGROUND: Providing user-friendly electronic data collection tools for large multicenter studies is key for obtaining high-quality research data. Research Electronic Data Capture (REDCap) is a software solution developed for setting up research databases with integrated graphical user interfaces for electronic data entry. The Swiss Mother and Child HIV Cohort Study (MoCHiV) is a longitudinal cohort study with around 2 million data entries dating back to the early 1980s. Until 2022, data collection in MoCHiV was paper-based. OBJECTIVE: The objective of this study was to provide a user-friendly graphical interface for electronic data entry for physicians and study nurses reporting MoCHiV data. METHODS: MoCHiV collects information on obstetric events among women living with HIV and children born to mothers living with HIV. Until 2022, MoCHiV data were stored in an Oracle SQL relational database. In this project, R and REDCap were used to develop an electronic data entry platform for MoCHiV with migration of already collected data. RESULTS: The key steps for providing an electronic data entry option for MoCHiV were (1) design, (2) data cleaning and formatting, (3) migration and compliance, and (4) add-on features. In the first step, the database structure was defined in REDCap, including the specification of primary and foreign keys, definition of study variables, and the hierarchy of questions (termed "branching logic"). In the second step, data stored in Oracle were cleaned and formatted to adhere to the defined database structure. Systematic data checks ensured compliance to all branching logic and levels of categorical variables. REDCap-specific variables and numbering of repeated events for enabling a relational data structure in REDCap were generated using R. In the third step, data were imported to REDCap and then systematically compared to the original data. In the last step, add-on features, such as data access groups, redirections, and summary reports, were integrated to facilitate data entry in the multicenter MoCHiV study. CONCLUSIONS: By combining different software tools-Oracle SQL, R, and REDCap-and building a systematic pipeline for data cleaning, formatting, and comparing, we were able to migrate a multicenter longitudinal cohort study from Oracle SQL to REDCap. REDCap offers a flexible way for developing customized study designs, even in the case of longitudinal studies with different study arms (ie, obstetric events, women, and mother-child pairs). However, REDCap does not offer built-in tools for preprocessing large data sets before data import. Additional software is needed (eg, R) for data formatting and cleaning to achieve the predefined REDCap data structure

    Using knowledge: the dilemmas of 'bridging research and policy'

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    The 'knowledge agenda' has become a central part of development discourse. This paper addresses one aspect of this discourse - the use of policy research in the social sciences - and the dilemmas that have been encountered by both development agencies and researchers in communicating and making use of that research. Development agencies as well as NGOs have initiated work to evaluate and document the effectiveness of research partnerships, knowledge capacity building and (social) science policy impact. As a multilateral initiative, the Global Development Network (GDN), and especially its 'Bridging Research and Policy' project, provides a vehicle to address issues related to research impact. Twelve perspectives on improving research and policy linkages are outlined to reveal that how the problem is defined shapes policy responses. Taken together, these explanations provide a multifaceted picture of the research-policy nexus indicating that there are many possible routes to 'bridging' research and policy. These diverse perspectives will be categorised into three broad categories of explanation: (i) supply-side; (ii) demand-led; and (iii) policy currents. However, knowledge is part of the solution to many development problems but not of itself a panacea

    Viral suppression and retention in HIV care during the postpartum period among women living with HIV: a longitudinal multicenter cohort study

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    BACKGROUND: Low rates of postnatal retention in HIV care and viral suppression have been reported in women living with HIV (WLWH) despite viral suppression at delivery. At the same time, postpartum follow-up is of crucial importance in light of the increasing support offered in many resource-rich countries including Switzerland to WLWH choosing to breastfeed their infant, if optimal scenario criteria are met. METHODS: We longitudinally investigated retention in HIV care, viral suppression, and infant follow-up in a prospective multicentre HIV cohort study of WLWH in the optimal scenario who had a live birth between January 2000 and December 2018. Risk factors for adverse outcomes in the first year postpartum were assessed using logistic and proportional hazard models. FINDINGS: Overall, WLWH were retained in HIV care for at least six months after 94.2% of the deliveries (694/737). Late start of combination antiretroviral therapy (cART) during the third trimester was found to be the main risk factor for failure of retention in HIV care (crude odds ratio [OR] 3.91; 95% confidence interval [CI], 1.50-10.22; p = 0.005). Among mothers on cART until at least one year after delivery, 4.4% (26/591) experienced viral failure, with illicit drugs use being the most important risk factor (hazard ratio [HR], 13.2; 95% CI, 2.35-73.6; p = 0.003). The main risk factors for not following the recommendations regarding infant follow-up was maternal depression (OR, 3.52; 95% CI, 1.18-10.52; p = 0.024). INTERPRETATION: Although the results are reassuring, several modifiable risk factors for adverse postpartum outcome, such as late treatment initiation and depression, were identified. These factors should be addressed in HIV care of all WLWH, especially those opting to breastfeed in resource-rich countries. FUNDING: This study has been financed within the framework of the Swiss HIV Cohort Study, supported by the Swiss National Science Foundation (grant #201369), by SHCS project 850 and by the SHCS research foundation

    Widely differing screening and treatment practice for osteoporosis in patients with inflammatory bowel diseases in the Swiss IBD cohort study.

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    Low bone mineral density (BMD) and osteoporosis remain frequent problems in patients with inflammatory bowel diseases (IBDs). Several guidelines with nonidentical recommendations exist and there is no general agreement regarding the optimal approach for osteoporosis screening in IBD patients. Clinical practice of osteoporosis screening and treatment remains insufficiently investigated.In the year 2014, a chart review of 877 patients included in the Swiss IBD Cohort study was performed to assess details of osteoporosis diagnostics and treatment. BMD measurements, osteoporosis treatment, and IBD medication were recorded.Our chart review revealed 253 dual-energy x-ray absorptiometry (DXA) scans in 877 IBD patients; osteoporosis was prevalent in 20% of tested patients. We identified widely differing osteoporosis screening rates among centers (11%-62%). A multivariate logistic regression analysis identified predictive factors for screening including steroid usage, long disease duration, and perianal disease; even after correction for all risk factors, the study center remained a strong independent predictor (odds ratio 2.3-21 compared to the center with the lowest screening rate). Treatment rates for patients with osteoporosis were suboptimal (55% for calcium, 65% for vitamin D) at the time of chart review. Similarly, a significant fraction of patients with current steroid medication were not treated with vitamin D or calcium (treatment rates 53% for calcium, 58% for vitamin D). For only 29% of patients with osteoporosis bisphosphonate treatment was started. Treatment rates also differed among centers, generally following screening rates. In patients with longitudinal DXA scans, calcium and vitamin D usage was significantly associated with improvement of BMD over time.Our analysis identified inconsistent usage of osteoporosis screening and underuse of osteoporosis treatment in IBD patients. Increasing awareness of osteoporosis as a significant clinical problem in IBD patients might improve patient care

    IL1B and DEFB1 Polymorphisms Increase Susceptibility to Invasive Mold Infection After Solid-Organ Transplantation.

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    BACKGROUND: Single-nucleotide polymorphisms (SNPs) in immune genes have been associated with susceptibility to invasive mold infection (IMI) among hematopoietic stem cell but not solid-organ transplant (SOT) recipients. METHODS: Twenty-four SNPs from systematically selected genes were genotyped among 1101 SOT recipients (715 kidney transplant recipients, 190 liver transplant recipients, 102 lung transplant recipients, 79 heart transplant recipients, and 15 recipients of other transplants) from the Swiss Transplant Cohort Study. Association between SNPs and the end point were assessed by log-rank test and Cox regression models. Cytokine production upon Aspergillus stimulation was measured by enzyme-linked immunosorbent assay in peripheral blood mononuclear cells (PBMCs) from healthy volunteers and correlated with relevant genotypes. RESULTS: Mold colonization (n = 45) and proven/probable IMI (n = 26) were associated with polymorphisms in the genes encoding interleukin 1β (IL1B; rs16944; recessive mode, P = .001 for colonization and P = .00005 for IMI, by the log-rank test), interleukin 1 receptor antagonist (IL1RN; rs419598; P = .01 and P = .02, respectively), and β-defensin 1 (DEFB1; rs1800972; P = .001 and P = .0002, respectively). The associations with IL1B and DEFB1 remained significant in a multivariate regression model (P = .002 for IL1B rs16944; P = .01 for DEFB1 rs1800972). The presence of 2 copies of the rare allele of rs16944 or rs419598 was associated with reduced Aspergillus-induced interleukin 1β and tumor necrosis factor α secretion by PBMCs. CONCLUSIONS: Functional polymorphisms in IL1B and DEFB1 influence susceptibility to mold infection in SOT recipients. This observation may contribute to individual risk stratification

    Pregnancy and delivery outcomes of HIV infected women in Switzerland 2003-2008

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    Objective: Rates of vertical HIV transmission between mother and child are low, allowing many HIV positive women to have children with near impunity. In this study, data from the Swiss Mother and Child HIV Cohort Study were used to describe maternal characteristics and their association with pregnancy outcomes in HIV positive women. Study design: HIV positive women were followed prospectively during their pregnancies and deliveries by anonymous questionnaires between January 2003 and October 2008. Adverse pregnancy outcomes included preterm delivery, preeclampsia and gestational diabetes mellitus. Results: This study included 266 HIV positive women, of which 67 (25.2%) were first diagnosed with HIV during pregnancy. Thirty percent (n=80) of the women had pregnancy complications after 24weeks of gestation. Preterm delivery was noted in 72 (27%) patients. Other complications included preeclampsia (n=7; 2.6%) and gestational diabetes (n=7; 2.6%). Older maternal age was the only risk factor associated with adverse pregnancy outcomes (adjusted odds ratio: 1.06, 95% confidence interval 1.01-1.12, P=0.02). Conclusions: HIV positive women, especially with advanced maternal age, have high-risk pregnancies and should be monitored as in an interdisciplinary setting. The preponderance of initial HIV diagnosis during pregnancy confirms the importance of HIV screening in pregnant wome
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