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Oral emtricitabine/tenofovir disoproxil fumarate (F/TDF) preexposure prophylaxis (PrEP) effectiveness against HIV acquisition highly depends on adherence. For men who have sex with men, a dosing study in the United States (US) population defined clinically meaningful tenofovir diphosphate (TFV-DP) thresholds in dried blood spots (DBS) based on the rounded 25th percentile for 2, 4, and 7 doses/week as 350, 700, and 1,250 fmol/punch. However, divergent efficacy results in the first generation randomized clinical trials of F/TDF PrEP among African women led to several hypotheses to question whether the pharmacology and adherence requirement for oral F/TDF PrEP may be different in cisgender women compared to what is already established for men. We conducted an open-label, parallel, randomized directly observed dosing (DOD) study of oral F/TDF PrEP among women without HIV who were not pregnant or breastfeeding in Kenya. Participants were randomly assigned to 2, 4, or 7 DOD F/TDF doses/week for 8 weeks. Blood was collected weekly, and TFV-DP and emtricitabine triphosphate (FTC-TP) concentrations in DBS and peripheral blood mononuclear cells (PBMCs) were quantified using validated liquid chromatography-tandem mass spectrometry. For DBS, concentrations were quantified from a 3-mm punch using the 70% methanol/30% water (70:30) extraction method as the primary process-the same method used for the original TFV-DP benchmarks derived in US adults, and additionally with 50% methanol/50% water (50:50) extraction using punches from the same DBS spot to compare the extraction performance of 70:30 versus 50:50 methods. The primary outcome was the steady-state fitted concentrations of TFV-DP and dose proportionality in DBS and the observed PBMC TFV-DP levels by study dosing groups. Secondary outcomes included the quantitative concentrations of FTC-TP in DBS, TFV-DP half-life in DBS, and the relative TFV-DP recovery from DBS using the 70:30 versus 50:50 extraction method. One-compartment population pharmacokinetic models were fit to estimate steady-state DBS concentrations. Descriptive statistics were summarized as range, means, and medians with interquartile range (IQR) for continuous outcomes and proportions for categorical variables. Fifty-four women were enrolled and randomized. Median age was 22 (IQR, 20-25) years. The observed median (IQR) week 8 TFV-DP concentrations in DBS were 359 (266-464), 749 (596-923), and 1,389 (1,151-1,551) fmol/punch after 2, 4, and 7 doses/week, respectively. At week 8, FTC-TP was quantifiable in 71%, 19%, and 0% DBS samples for 7, 4, and 2 doses/week groups, respectively. Fitted median (IQR) steady-state DBS TFV-DP concentrations were 416 (316, 516), 832 (631, 1,033), and 1,457 (1,106, 1,808) fmol/punch for 2, 4, and 7 doses/week, respectively, similar to previous estimates in US adults. TFV-DP exhibited a mean half-life of 17.5 days (95%CI: 16.7, 18.4) in DBS and steady-state TFV-DP concentrations varied in direct proportion to the dosing frequency [slope: 1.02 90% confidence interval 0.84, 1.20]. The 50:50 DBS extraction method yielded 1.27 (95% CI 1.25, 1.28) higher TFV-DP concentrations compared to the 70:30 method. When the 1.27 conversion factor was applied to the original 70:30 method-derived TFV-DP thresholds, the updated TFV-DP adherence interpretation benchmarks based on the 50:50 extraction were: <450 for <2 dose/week, 450-899 for 2-3 doses/week, 900-1,599 for 4-6 doses/week, and ≥1,600 fmol/punch for 7 doses/week. The observed mean (standard deviation) steady-state PBMC TFV-DP concentrations was 11.99 ± 8.47, 31.81 ± 15.66, and 63.1 ± 28.97 fmol/106 cells after 2, 4, and 7 doses/week, respectively. Overall, oral F/TDF PrEP was well tolerated. No grade 3 or higher adverse events were observed during the dosing phase. The primary study limitation was dosing for 8 weeks, but population pharmacokinetic modeling enabled steady-state estimates. Steady-state DBS TFV-DP concentrations from directly observed F/TDF PrEP dosing in African cisgender women participants are similar to previous estimates defined from US-based participants. These data demonstrate that cisgender women achieve similar DBS and PBMC TFV-DP concentrations as men for the same adherence level and validate the original TFV-DP benchmarks to interpret F/TDF adherence in HIV prevention studies and PrEP programs among cisgender women. Clinicaltrials.gov: NCT05057858.

Sexually transmitted infection (STI) rates are high globally, particularly in regions like sub-Saharan Africa, where there is also a disproportionate burden of HIV . Doxycycline post-exposure prophylaxis (doxyPEP) is a novel strategy intended to prevent bacterial STIs following potential exposure. The dPEP Kenya Study, the first trial of doxyPEP for STI prevention among cisgender women, found that doxyPEP did not reduce STIs in the setting of low use of doxyPEP by objective drug concentrations. To assess barriers and facilitators to doxyPEP adherence, we explored participants' experiences during the dPEP Kenya Study. We conducted serial in-depth interviews (n = 40) and 4 focus group discussions (n = 29) of participants randomized to take doxyPEP. Transcripts were analyzed using an inductive content analysis approach. Side effects, such as nausea from taking doxyPEP on an empty stomach, dosage interpretation challenges, pill burden, and concerns about stigma and partner reactions hindered adherence. Support from partners, family, and peers, familiarity with doxycycline, and the use of discreet pill carriers facilitated doxyPEP use. Decreasing dosage frequency, promoting the use of discreet pill carriers, and addressing stigma through community-driven communication strategies may improve future doxyPEP uptake and adherence. Clinical trial number. This trial was registered in the ClinicalTrials.gov under registration number, NCT04050540 on 06th August 2019.

Abstarct Eighty normal dogs of four morphologically disparate breeds (Pembroke Welsh Corgi, Miniature Poodle, Afghan Hound, Golden Retriever) (twenty of each breed), were studied by echocardiography to determine the importance of breed and weight in establishing normal echocardiographic reference ranges. Echocardiographic measurements included left-ventricular chamber dimension at systole and end-diastole, right-ventricular chamber dimension at end-diastole, interventricular septal thickness at systole and end-diastole, left-ventricular free wall thickness at systole and end-diastole, E-point septal separation, aortic root dimension at end-diastole, left atrial dimension, and fractional shortening. Analyses of covariance indicated that for all measurements except right-ventricular chamber dimension, the means were significantly different among breeds, after the differences in weight were taken into account. Echocardiographic measurements are variable even within the same breed. Breed must be considered in establishing echocardiographic measurement reference ranges. Echocardiographic values for each breed are presented. (Journal of Veterinary Internal Medicine 1992; 6:220–224)

Abstarct Acromegaly was diagnosed in 14 middle-aged to old cats of mixed breeding. Thirteen (93%) of the cats were male and one was female. The earliest clinical signs in the 14 cats included polyuria, polydipsia, polyphagia, all of which were associated with untreated diabetes mellitus. All developed severe insulin resistance within a few months; peak insulin dosages required to control severe hyperglycemia ranged from 20 to 130 U per day. Other clinical findings weeks to months after diagnosis included enlargement of one or more organs (e.g., liver, heart, kidneys, and tongue) (n = 14), cardiomyopathy (n = 13), increase in body size and weight gain (n = 8), nephropathy associated with azotemia and clinical signs of renal failure (n = 7), degenerative arthropathy (n = 6), and central nervous system signs (i.e., circling and seizures) caused by enlargement of the pituitary tumor (n = 2). The diagnosis of acromegaly was confirmed by demonstration of extremely high basal serum growth hormone concentrations (22 to 131 μg/1) in all cats. Computerized tomography disclosed a mass in the region of the pituitary gland and hypothalamus in five of the six cats in which it was performed. Two cats were treated by cobalt radiotherapy followed by administration of a somatostatin analogue (octreotide), whereas two cats were treated with octreotide alone. Treatment had little to no effect in decreasing serum GH concentrations in any of the cats. Eleven of the 14 cats were euthanized or died four to 42 months (median survival time, 20.5 months) after the onset of acromegaly because of renal failure (n = 2), congestive heart failure (n = 1), concomitant renal failure and congestive heart failure (n = 3), progressive neurologic signs (n = 2), persistent anorexia and lethargy of unknown cause (n - 1), the owner's unwillingness to treat the diabetes mellitus (n = 1), or unknown causes (n = 1). Results of necropsy examination in ten cats revealed a large pituitary acidophil adenoma (n = 10), marked left ventricular and septal hypertrophy (n = 7), dilated cardiomyopathy (n = 1), arthropathy affecting the shoulder, elbow, or stifle (n = 5), and glomerulopathy characterized by expansion of the mesangial matrix and variable periglomerular fi-brosis (n = 10). (Journal of Veterinary Internal Medicine 1990; 4:192–201)

IntroductionSouth Africa has the highest national burden of HIV globally. Understanding drivers of HIV acquisition in recently completed, prospective studies in which HIV was an endpoint may help inform the strategy and investments in national HIV prevention efforts and guide the design of future HIV prevention trials. We assessed HIV incidence and correlates of incidence among women enrolled in ECHO (Evidence for Contraceptive Options and HIV Outcomes), a large, open-label randomized clinical trial that compared three highly effective. reversible methods of contraception and rates of HIV acquisition.MethodsDuring December 2015 to October 2018, ECHO followed sexually active, HIV-seronegative women, aged 16-35 years, seeking contraceptive services and willing to be randomized to one of three contraceptive methods (intramuscular depot medroxyprogesterone acetate, copper intrauterine device, or levonorgestrel implant) for 12-18 months at nine sites in South Africa. HIV incidence based on prospectively observed HIV seroconversion events. Cox proportional hazards regression models were used to define baseline cofactors related to incident HIV infection.Results5768 women were enrolled and contributed 7647 woman-years of follow-up. The median age was 23 years and 62.5% were ≤24 years. A total of 345 incident HIV infections occurred, an incidence of 4.51 per 100 woman-years (95%CI 4.05-5.01). Incidence was >3 per 100 woman-years at all sites. Age ≤24 years, baseline infection with sexually transmitted infections, BMI≤30, and having new or multiple partners in the three months prior to enrollment were associated with incident HIV.ConclusionsHIV incidence was high among South African women seeking contraceptive services. Integration of diagnostic management of sexually transmitted infections alongside delivery of HIV prevention options in health facilities providing contraception services are needed to mitigate ongoing risks of HIV acquisition for this vulnerable population.Clinical trial registrationClinicalTrials.gov, number NCT02550067 was the main Clinical Trial from which this secondary, non-randomized / observational analysis was derived with data limited to just South African sites.

Enhanced fibroblast growth factor 21 (FGF21) production and circulation has been linked to the metabolic adaptation to starvation. Here, we demonstrated that hepatic FGF21 expression is induced by dietary protein restriction, but not energy restriction. Circulating FGF21 was increased 10-fold in mice and rats fed a low-protein (LP) diet. In these animals, liver Fgf21 expression was increased within 24 hours of reduced protein intake. In humans, circulating FGF21 levels increased dramatically following 28 days on a LP diet. LP-induced increases in FGF21 were associated with increased phosphorylation of eukaryotic initiation factor 2α (eIF2α) in the liver, and both baseline and LP-induced serum FGF21 levels were reduced in mice lacking the eIF2α kinase general control nonderepressible 2 (GCN2). Finally, while protein restriction altered food intake, energy expenditure, and body weight gain in WT mice, FGF21-deficient animals did not exhibit these changes in response to a LP diet. These and other data demonstrate that reduced protein intake underlies the increase in circulating FGF21 in response to starvation and a ketogenic diet and that FGF21 is required for behavioral and metabolic responses to protein restriction. FGF21 therefore represents an endocrine signal of protein restriction, which acts to coordinate metabolism and growth during periods of reduced protein intake.

It is important to realize that guidelines cannot always account for individual variation among patients. They are not intended to supplant physician judgment with respect to particular patients or special clinical situations. IDSA considers adherence to these guidelines to be voluntary, with the ultimate determination regarding their application to be made by the physician in the light of each patient's individual circumstances.

Dietary protein restriction is increasingly recognized as a unique approach to improve metabolic health, and there is increasing interest in the mechanisms underlying this beneficial effect. Recent work indicates that the hormone FGF21 mediates the metabolic effects of protein restriction in young mice. Here we demonstrate that protein restriction increases lifespan, reduces frailty, lowers body weight and adiposity, improves physical performance, improves glucose tolerance, and alters various metabolic markers within the serum, liver, and adipose tissue of wildtype male mice. Conversely, mice lacking FGF21 fail to exhibit metabolic responses to protein restriction in early life, and in later life exhibit early onset of age-related weight loss, reduced physical performance, increased frailty, and reduced lifespan. These data demonstrate that protein restriction in aging male mice exerts marked beneficial effects on lifespan and metabolic health and that a single metabolic hormone, FGF21, is essential for the anti-aging effect of this dietary intervention. The restriction of dietary protein or amino acid intake is well established to extend lifespan in multiple species. Here, the authors show that the endocrine hormone FGF21 is necessary for dietary protein restriction to extend lifespan and improve metabolic health in aged, male mice.

Background The infant intestinal microbiome plays an important role in metabolism and immune development with impacts on lifelong health. The linkage between the taxonomic composition of the microbiome and its metabolic phenotype is undefined and complicated by redundancies in the taxon-function relationship within microbial communities. To inform a more mechanistic understanding of the relationship between the microbiome and health, we performed an integrative statistical and machine learning-based analysis of microbe taxonomic structure and metabolic function in order to characterize the taxa-function relationship in early life. Results Stool samples collected from infants enrolled in the New Hampshire Birth Cohort Study (NHBCS) at approximately 6-weeks ( n  = 158) and 12-months ( n  = 282) of age were profiled using targeted and untargeted nuclear magnetic resonance (NMR) spectroscopy as well as DNA sequencing of the V4-V5 hypervariable region from the bacterial 16S rRNA gene. There was significant inter-omic concordance based on Procrustes analysis (6 weeks: p  = 0.056; 12 months: p  = 0.001), however this association was no longer significant when accounting for phylogenetic relationships using generalized UniFrac distance metric (6 weeks: p  = 0.376; 12 months: p  = 0.069). Sparse canonical correlation analysis showed significant correlation, as well as identifying sets of microbe/metabolites driving microbiome-metabolome relatedness. Performance of machine learning models varied across different metabolites, with support vector machines (radial basis function kernel) being the consistently top ranked model. However, predictive R 2 values demonstrated poor predictive performance across all models assessed (avg: − 5.06% -- 6 weeks; − 3.7% -- 12 months). Conversely, the Spearman correlation metric was higher (avg: 0.344–6 weeks; 0.265–12 months). This demonstrated that taxonomic relative abundance was not predictive of metabolite concentrations. Conclusions Our results suggest a degree of overall association between taxonomic profiles and metabolite concentrations. However, lack of predictive capacity for stool metabolic signatures reflects, in part, the possible role of functional redundancy in defining the taxa-function relationship in early life as well as the bidirectional nature of the microbiome-metabolome association. Our results provide evidence in favor of a multi-omic approach for microbiome studies, especially those focused on health outcomes.

Microorganisms associated with coastal sands serve as a natural biofilter, providing essential nutrient recycling in nearshore environments and acting to maintain coastal ecosystem health. Anthropogenic stressors often impact these ecosystems, but little is known about whether these disturbances can be identified through microbial community change. The blowout of the Macondo Prospect reservoir on April 20, 2010, which released oil hydrocarbons into the Gulf of Mexico, presented an opportunity to examine whether microbial community composition might provide a sensitive measure of ecosystem disturbance. Samples were collected on four occasions, beginning in mid-June, during initial beach oiling, until mid-November from surface sand and surf zone waters at seven beaches stretching from Bay St. Louis, MS to St. George Island, FL USA. Oil hydrocarbon measurements and NOAA shoreline assessments indicated little to no impact on the two most eastern beaches (controls). Sequence comparisons of bacterial ribosomal RNA gene hypervariable regions isolated from beach sands located to the east and west of Mobile Bay in Alabama demonstrated that regional drivers account for markedly different bacterial communities. Individual beaches had unique community signatures that persisted over time and exhibited spatial relationships, where community similarity decreased as horizontal distance between samples increased from one to hundreds of meters. In contrast, sequence analyses detected larger temporal and less spatial variation among the water samples. Superimposed upon these beach community distance and time relationships, was increased variability in bacterial community composition from oil hydrocarbon contaminated sands. The increased variability was observed among the core, resident, and transient community members, indicating the occurrence of community-wide impacts rather than solely an overprinting of oil hydrocarbon-degrading bacteria onto otherwise relatively stable sand population structures. Among sequences classified to genus, Alcanivorax, Alteromonas, Marinobacter, Winogradskyella, and Zeaxanthinibacter exhibited the largest relative abundance increases in oiled sands.