Insulin acutely improves mitochondrial function of rat and human skeletal muscle by increasing coupling efficiency of oxidative phosphorylation.

Insulin is essential for the regulation of fuel metabolism and triggers the uptake of glucose by skeletal muscle. The imported glucose is either stored or broken down, as insulin stimulates glycogenesis and ATP synthesis. The mechanism by which ATP production is increased is incompletely understood at present and, generally, relatively little functional information is available on the effect of insulin on mitochondrial function. In this paper we have exploited extracellular flux technology to investigate insulin effects on the bioenergetics of rat (L6) and human skeletal muscle myoblasts and myotubes. We demonstrate that a 20-min insulin exposure significantly increases (i) the cell respiratory control ratio, (ii) the coupling efficiency of oxidative phosphorylation, and (iii) the glucose sensitivity of anaerobic glycolysis. The improvement of mitochondrial function is explained by an insulin-induced immediate decrease of mitochondrial proton leak. Palmitate exposure annuls the beneficial mitochondrial effects of insulin. Our data improve the mechanistic understanding of insulin-stimulated ATP synthesis, and reveal a hitherto undisclosed insulin sensitivity of cellular bioenergetics that suggests a novel way of detecting insulin responsiveness of cells

Local anesthetics induce autophagy in young permanent tooth pulp cells

Pulp cells are essential for tooth development, and dentin repair and regeneration. In addition these cells have been identified as an important stem cell source. Local anesthetics are widely used in dental clinics, as well as the other clinical disciplines and have been suggested to interfere with human permanent tooth development and induce tooth agenesis through unknown mechanisms. Using pig model and human young permanent tooth pulp cells, our research has identified that the local anesthetics commonly used in clinics can affect cell proliferation. Molecular pathway profiling suggested that LC3II is one of the earliest molecules induced by the agents and p62 is the only common downstream target identified for all the drugs tested. The effect of the drugs could be partially recovered by V-ATPase inhibitor only if early intervention is performed. Our results provide novel evidence that local anesthetics could affect tooth cell growth that potentially can have impacts on tooth development

Statistics versus livelihoods: questioning Rwanda’s pathway out of poverty

Recent statistics indicate that poverty in Rwanda decreased impressively between 2006 and 2014. This seems to confirm Rwanda’s developmental progress. This article however argues for a more cautious interpretation of household survey data. The authors contrast macro-level statistical analysis with in-depth field research on livelihood conditions. Macro-economic numbers provide interesting information, however differentiated evidence is required to understand how poverty ‘works’ in everyday life. On the basis of the Rwandan case study, the authors conclude that because of the high political stakes of data collection and analysis, and given that relations of power influence the production of knowledge on poverty, cross-checking is crucial

Impact of maternal ART on mother-to-child transmission (MTCT) of HIV at six weeks postpartum in Rwanda

BACKGROUND: In 2010, Rwanda adopted ART for prevention of mother to child transmission of HIV from pregnant women living with HIV during pregnancy and breasfeeding period. This study examines rates of mother-to-childtransmission of HIV at 6–10 weeks postpartum and risk factors for mother-to-child transmission of HIV (MTCT) among HIV infected women on ART during pregnancy and breastfeeding. METHODS: A cross-sectional survey study was conducted between July 2011–June 2012 among HIV-exposed infants aged 6–10 weeks and their mothers/caregivers. Stratified multi-stage, probability proportional to size and systematic sampling to select a national representative sample of clients. Consenting mothers/caregivers were interviewed on demographic and program interventions. Dry blood spots from HIV-exposed infants were collected for HIV testing using DNA PCR technique. Results are weighted for sample realization. Univariable analysis of socio-demographic and programmatic determinants of early mother-to-child transmission of HIV was conducted. Variables were retained for final multivariable models if they were either at least of marginal significance (p-value < 0.10) or played a confounding role (the variable had a noticeable impact > 10% change on the effect estimate). RESULTS: The study sample was 1639 infants with HIV test results. Twenty-six infants were diagnosed HIV-positive translating to a weighted MTCT estimate of 1.58% (95% CI 1.05–2.37%). Coverage of most elimination of MTCT (EMTCT) program interventions, was above 80, and 90.4% of mother-infant pairs received antiretroviral treatment or prophylaxis. Maternal ART and infant antiretroviral prophylaxis (OR 0.01; 95%CI 0.001–0.17) and maternal age older than 25 years were significantly protective (OR 0.33; 95%CI 0.14–0.78). No disclosure of HIV status, not testing for syphilis during pregnancy and preterm birth were significant risk factors for MTCT. Factors suggesting higher sociodemographic status (flush toilet, mother self-employed) were borderline risk factors for MTCT. CONCLUSION: ART for all women during pregnancy and breastfeeding was associated with the estimated low MTCT rate of 1.58%. Mothers who did not receive a full package of anti-retroviral therapy according to the Rwanda EMTCT protocol, and young and single mothers were at higher risk of MTCT and should be targeted for support in preventing HIV infection