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The anorexigenic peptide glucagon-like peptide-1 (GLP-1) is secreted from gut enteroendocrine cells and brain preproglucagon (PPG) neurons, which, respectively, define the peripheral and central GLP-1 systems. PPG neurons in the nucleus tractus solitarii (NTS) are widely assumed to link the peripheral and central GLP-1 systems in a unified gut-brain satiation circuit. However, direct evidence for this hypothesis is lacking, and the necessary circuitry remains to be demonstrated. Here we show that PPG NTS neurons encode satiation in mice, consistent with vagal signalling of gastrointestinal distension. However, PPG NTS neurons predominantly receive vagal input from oxytocin-receptor-expressing vagal neurons, rather than those expressing GLP-1 receptors. PPG NTS neurons are not necessary for eating suppression by GLP-1 receptor agonists, and concurrent PPG NTS neuron activation suppresses eating more potently than semaglutide alone. We conclude that central and peripheral GLP-1 systems suppress eating via independent gut-brain circuits, providing a rationale for pharmacological activation of PPG NTS neurons in combination with GLP-1 receptor agonists as an obesity treatment strategy.

Cytology remains the mainstay of cervical cancer screening in South Africa (SA), however false negative rates are 25-50%. In contrast, human papillomavirus (HPV) screening techniques have higher sensitivity for cervical cancer precursors. The cobas® 4800 HPV test detects pooled high-risk HPV types and individual genotypes HPV 16 and 18. Using a mathematical budget impact model, the study objective was to evaluate the clinical and budget impact of replacing primary liquid-based cytology (LBC) with primary HPV-based screening strategies. In SA, current LBC screening practice recommends one test every ten years, followed by large loop excision of the transformation zone (LLETZ) if indicated. HPV testing can be performed from an LBC sample, where no additional consultations nor samples are required. In the budget impact model, LBC screening for 2 cycles (one test every ten years) was compared to cobas® 4800 HPV test for 2 cycles (one test every 5 years). The model inputs were gathered from literature and primary data sources. Indicative prices for LBC and cobas® 4800 HPV test were R189 and R457, respectively. Model results indicate that best outcomes for detection of disease were seen using cobas® 4800 HPV test. Forty-eight percent of cervical cancer cases were detected compared to 28% using LBC, and 50% of cervical intraepithelial neoplasia (CIN) 2 and CIN3 cases, compared to 25% with LBC. The budget impact analysis predicted that the cost per detected case of CIN2 or higher would be R 56,835 and R46,980 for the cobas® 4800 HPV and LBC scenarios, respectively. This equates to an incremental cost per detected case of CIN2 or higher of R9 855. From this model we conclude that a primary HPV screening strategy will have a significant clinical impact on disease burden in South Africa., Competing Interests: The authors’ affiliation with TCD Outcomes Research does not alter our adherence to PLOS ONE policies on sharing data and materials.

Purpose: To evaluate the role of high-risk human papillomavirus (HR-HPV) infection in periocular sebaceous carcinoma (SC) using multiple methods of detection, and to determine whether p16 overexpression is present and can be used as a surrogate marker for HR-HPV., Design: Retrospective observational case series with laboratory investigations., Methods: Unstained paraffin sections of 35 cases of periocular SC were analyzed with immunohistochemistry for p16 and subjected to polymerase chain reaction (PCR) for HR-HPV. A subset of 18 lesions that were p16-positive was further studied with a novel method of mRNA in situ hybridization (ISH) for the detection of transcriptionally active HR-HPV, an advanced technique with an enhanced sensitivity and specificity., Results: The clinical findings were in keeping with those of comparable earlier studies. Strong immunohistochemical p16 positivity (meeting the criterion of >70% nuclear and cytoplasmic staining) was present in 29 of 35 cases of periocular SC (82.9%). The selected 18 p16-positive cases tested were negative for HR-HPV using mRNA ISH. PCR yielded unequivocal results with adequate DNA isolated in 24 cases, 23 of which were negative for HR-HPV. One case was positive for HPV type 16, which was found to be a false positive as collaterally determined by mRNA ISH negativity., Conclusion: No evidence was found for HR-HPV as an etiologic agent in the development of periocular SC using multiple modalities to maximize sensitivity and specificity and reduce the limitations of any single test. p16 overexpression is common in periocular SC but unrelated to HR-HPV status. Although p16 may be used as a surrogate marker for HR-HPV status in other tissue sites, this interpretation of p16 positivity is not applicable to periocular SC., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Background: The prevalence of myocarditis and cardiotropic viral infection in human immunodeficiency virus (HIV)-associated cardiomyopathy is unknown in Africa., Methods: Between April 2002 and December 2007, we compared the prevalence of myocarditis and cardiotropic viral genomes in HIV-associated cardiomyopathy cases with HIV-negative idiopathic dilated cardiomyopathy patients (i.e. negative controls for immunodeficiency) and heart transplant recipients (i.e. positive controls for immunodeficiency) who were seen at Groote Schuur Hospital, Cape Town, South Africa. Myocarditis was sought on endomyocardial biopsy using the imunohistological criteria of the World Heart Federation in 33 patients, 14 of whom had HIV-associated cardiomyopathy, eight with idiopathic dilated cardiomyopathy and 11 heart transplant recipients., Results: Myocarditis was present in 44% of HIV-associated cardiomyopathy cases, 36% of heart transplant recipients, and 25% of participants with idiopathic dilated cardiomyopathy. While myocarditis was acute in 50% of HIV- and heart transplant-associated myocarditis, it was chronic in all those with idiopathic dilated cardiomyopathy. Cardiotropic viral infection was present in all HIV-associated cardiomyopathy and idiopathic dilated cardiomyopathy cases, and in 90% of heart transplant recipients. Multiple viruses were identified in the majority of cases, with HIV-associated cardiomyopathy, heart transplant recipients and idiopathic dilated cardiomyopathy patients having an average of 2.5, 2.2 and 1.1 viruses per individual, respectively., Conclusions: Acute myocarditis was present in 21% of cases of HIV-associated cardiomyopathy, compared to none of those with idiopathic dilated cardiomyopathy. Infection with multiple cardiotropic viruses may be ubiquitous in Africans, with a greater burden of infection in acquired immunodeficiency states.