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Background We aimed to determine the prevalence of hepatitis B virus (HBV) infection among people with human immunodeficiency virus (PWH) in rural and periurban communities in Botswana. Methods PWH from a previous population-based study, the Botswana Prevention Combination Project, which enrolled adults in 30 communities across Botswana (2013–2018), were screened for HBV surface antigen (HBsAg) and HBV core antibody (anti-HBc). HBsAg-positive (HBsAg+) samples were further screened for HBV core immunoglobulin M antibodies (anti-HBc immunoglobulin M [IgM]) and HBV e antigen (HBeAg). We quantified HBV viral load on participants who tested positive (n = 148) and negative for HBsAg (n = 381). Results Of 3304 participants tested, 271 (8% [95% confidence interval {CI}, 7%–9%]) were HBsAg+ while 1788 (56% [95% CI, 54%–57%]) of 3218 PWH whom we tested had positive anti-HBc. Approximately 88% of HBsAg+ participants were on antiretroviral therapy (ART), 40% and 56% of whom were receiving lamivudine- and tenofovir-containing ART, respectively. Male sex (relative risk ratio [RRR], 1.8 [95% CI, 1.2–2.7]) and the northern geographic region (RRR, 2.5 [95% CI, 1.4–4.7]) were independent predictors of HBV infection (HBsAg+). Of 381 persons with negative HBsAg who were tested for occult HBV, 126 (33% [95% CI, 29%–38%]) had positive HBV DNA. Eleven participants were highly viremic with high HBV viral load while on a lamivudine- or tenofovir-containing regimen. Ten (91%) of these participants also had positive HBeAg serology, while 4 (36%) had positive anti-HBc IgM serology. Conclusions The prevalence of HBV was high among PWH in Botswana while on ART regimens with activity against HBV.

Chemical investigation of the root wood of

Chemical investigation of the root wood of Erythrina livingstoniana led to the isolation of one previously undescribed isoflavan (3S,3″R)-7-hydroxy-2′-methoxy-[3″-hydroxy-2″,2″-dimethylpyrano (3′,4′)] isoflavan 1, together with eleven known compounds 2-12. The structure of compound 1 was elucidated on the basis of extensive spectroscopic and spectrometric analyses (1 D and 2 D-NMR and APCI-HRMS), with absolute configurations established by comparison of experimental and DFT calculated ECD data. The assignment of the absolute configurations of C-3 and C-3″ of compounds 2 and 3, respectively, were reported for the first time. Compounds 1 − 4 were evaluated for their antibacterial activities in vitro against E. coli ATCC 25922 and S. aureus ATCC 25923. Compound 1 exhibited moderate antibacterial activity with MIC value of 0.063 mg/mL against the clinically relevant risk-group 2 (RG-2) bacterium S. aureus.

BackgroundCOVID-19 found the world in a state of unpreparedness. While research efforts to develop a vaccine are on-going, others have suggested the use of available vaccines to boost innate immunity.ObjectiveWe analysed three databases: UNICEF Immunization Coverage, Worldometer Corona Virus Updates and World Bank List of Economies to establish the association, if any, between vaccination for various diseases and COVID-19 death rates and recoveries across world economies.ResultsMean percentage death rates were lower in countries that vaccinated for Hepatitis-B birth dose (2.53% vs 3.79%, p = 0.001), Bacille Calmette-Guérin Vaccine (2.93% vs 5.10%, p = 0.025) and Inactivated Polio Vaccine 1st dose (2.8% vs 4.01%, p = 0.022) than those which did not report vaccination. In high income countries, a significant negative correlation with death rates was observed with vaccination for Measles-containing vaccine 2nd dose (r = –0.290, p = 0.032), Rubella-containing vaccine 1st dose (r = –0.325, p = 0.015), Hepatitis B 3rd dose (r = –0.562, p = 3.3 x10−5), Inactivated Polio vaccine 1st dose (r = –0.720, p = 0.008). Inactivated Polio Vaccine 1st dose and Measles-containing vaccine 2nd dose also correlated with better recoveries. In Low Income countries, only Rubella-containing vaccine correlated with lower deaths while Yellow fever vaccine was associated with poorer recoveries.ConclusionOur analysis corroborates the potential benefit of vaccination and warrant further research to explore the rationale for repurposing other vaccines to fight COVID-19.

The causative agent of TB, Mycobacterium tuberculosis (Mtb) is once again the world’s number one infectious killer. M. tuberculosis resides primarily within macrophages and metabolic reprogramming within this intracellular niche is a crucial determinant of virulence. We previously applied the metabolic modelling-based tool 13C-flux spectral analysis (13C-FSA) to show that intracellular M. tuberculosis co-metabolises multiple gluconeogenic and glycolytic carbon substrates by utilizing the reactions of the phosphoenolpyruvate (PEP)-pyruvate-oxaloacetate (OAA) or anaplerotic (ANA) node. However, predicting the metabolic mode of operation required for intracellular survival is chellenging using a metabolic network as the ANA node consists of several apparently functionally redundant bidirectional reactions. Here we use multiple techniques including 13C isotopomer profiling, lipid analysis and fluorescent reporter strains to dissect the role of the ANA node. We show that this node has unexpected roles in the life cycle of M. tuberculosis including lipid biosynthesis, protection from known toxic intracellular carbon sources and redox regulation. Inhibiting enzymes at this node with novel therapeutic compounds restricts the growth of M. tuberculosis and limits the ability of this formidable pathogen to survive within the human host cell identifying the ANA node as a potential druggable pathway for controlling TB.

Enzymes at the phosphoenolpyruvate (PEP)–pyruvate–oxaloacetate or anaplerotic (ANA) node control the metabolic flux to glycolysis, gluconeogenesis, and anaplerosis. Here we used genetic, biochemical, and 13C isotopomer analysis to characterize the role of the enzymes at the ANA node in intracellular survival of the world's most successful bacterial pathogen, Mycobacterium tuberculosis (Mtb). We show that each of the four ANA enzymes, pyruvate carboxylase (PCA), PEP carboxykinase (PCK), malic enzyme (MEZ), and pyruvate phosphate dikinase (PPDK), performs a unique and essential metabolic function during the intracellular survival of Mtb. We show that in addition to PCK, intracellular Mtb requires PPDK as an alternative gateway into gluconeogenesis. Propionate and cholesterol detoxification was also identified as an essential function of PPDK revealing an unexpected role for the ANA node in the metabolism of these physiologically important intracellular substrates and highlighting this enzyme as a tuberculosis (TB)-specific drug target. We show that anaplerotic fixation of CO2 through the ANA node is essential for intracellular survival of Mtb and that Mtb possesses three enzymes (PCA, PCK, and MEZ) capable of fulfilling this function. In addition to providing a back-up role in anaplerosis we show that MEZ also has a role in lipid biosynthesis. MEZ knockout strains have an altered cell wall and were deficient in the initial entry into macrophages. This work reveals that the ANA node is a focal point for controlling the intracellular replication of Mtb, which goes beyond canonical gluconeogenesis and represents a promising target for designing novel anti-TB drugs.