The Milnor-Witt motivic ring spectrum and its associated theories

We build a ring spectrum representing Milnor-Witt motivic cohomology, as well as its \'etale local version and show how to deduce out of it three other theories: Borel-Moore homology, cohomology with compact support and homology. These theories, as well as the usual cohomology, are defined for singular schemes and satisfy the properties of their motivic analog (and more), up to considering more general twists. In fact, the whole formalism of these four theories can be functorially attached to any ring spectrum, giving finally maps between the Milnor-Witt motivic ones to the classical motivic ones.Comment: 28 pages. Comments welcom

Increasing Awareness and Use of Iodised Salt in a Marginalised Community Setting in North-West Pakistan

Iodine deficiency is still prevalent in parts of Pakistan, despite the introduction of a national Iodine Deficiency Disorder Control Programme in 1994. The purpose of this study was to gain an understanding of the knowledge, attitudes and practice regarding the use of iodised salt in a brick kiln community, and to use this information to design an intervention to increase its consumption. A cross-sectional survey was used to assess the use of iodised salt and focus group discussions explored the attitudes and barriers to its use. Thematically analysed transcripts informed the design of a 4-month intervention. Iodised salt sales and urine iodine concentration (UIC) were monitored to assess the effectiveness of the intervention. At baseline, 2.6% of households reported use of iodised salt and barriers included its higher cost and belief about a negative impact on reproduction. During the intervention, sales of salt labelled as iodised increased by 45%, however this was not reflected in an increase in UIC. This study highlighted the positive impact of education and awareness raising on iodised salt consumption in a hard to reach, marginalised community. However, issues regarding adequate iodisation by local producers and appropriate storage also need to be urgently addressed at a provincial level

A blind spot? Confronting the stigma of hepatitis B virus (HBV) infection - A systematic review

Background: Stigma, poverty, and lack of knowledge present barriers to the diagnosis and treatment of chronic infection, especially in resource-limited settings. Chronic Hepatitis B virus (HBV) infection is frequently asymptomatic, but accounts for a substantial long-term burden of morbidity and mortality. In order to improve the success of diagnostic, treatment and preventive strategies, it is important to recognise, investigate and tackle stigma. We set out to assimilate evidence for the nature and impact of stigma associated with HBV infection, and to suggest ways to tackle this challenge. Methods: We carried out a literature search in PubMed using the search terms ‘hepatitis B’, ‘stigma’ to identify relevant papers published between 2007 and 2017 (inclusive), with a particular focus on Africa. Results: We identified a total of 32 articles, of which only two studies were conducted in Africa. Lack of knowledge of HBV was consistently identified, and in some settings there was no local word to describe HBV infection. There were misconceptions about HBV infection, transmission and treatment. Healthcare workers provided inaccurate information to individuals diagnosed with HBV, and poor understanding resulted in lack of preventive measures. Stigma negatively impacted on help-seeking, screening, disclosure, prevention of transmission, and adherence to treatment, and had potential negative impacts on mental health, wellbeing, employment and relationships. Conclusion: Stigma is a potentially major barrier to the successful implementation of preventive, diagnostic and treatment strategies for HBV infection, and yet we highlight a ‘blind spot’, representing a lack of data and limited recognition of this challenge. There is a need for more research in this area, to identify and evaluate interventions that can be used effectively to tackle stigma, and to inform collaborative efforts between patients, clinical services, policy makers, traditional healers, religious leaders, charity organisations and support groups.</ns4:p

Modulation of HIV-1 Gag NC/p1 cleavage efficiency affects protease inhibitor resistance and viral replicative capacity

<p>Abstract</p> <p>Background</p> <p>Mutations in the substrate of HIV-1 protease, especially changes in the NC/p1 cleavage site, can directly contribute to protease inhibitor (PI) resistance and also compensate for defects in viral replicative capacity (RC) due to a drug resistant protease. These NC/p1 changes are known to enhance processing of the Gag protein. To investigate the capacity of HIV-1 to modulate Gag cleavage and its consequences for PI resistance and RC, we performed a detailed enzymatic and virological analysis using a set of PI resistant NC/p1 variants (HXB2^431V, HXB2^436E+437T, HXB2^437Tand HXB2^437V).</p> <p>Results</p> <p>Here, we demonstrate that single NC/p1 mutants, which displayed only a slight increase in PI resistance did not show an obvious change in RC. In contrast, the double NC/p1 mutant, which displayed a clear increase in processing efficiency and PI resistance, demonstrated a clear reduction in RC. Cleavage analysis showed that a tridecameric NC/p1 peptide representing the double NC/p1 mutant was cleaved in two specific ways instead of one.</p> <p>The observed decrease in RC for the double NC/p1 mutant (HXB2^436E+437T) could (partially) be restored by either reversion of the 436E change or by acquisition of additional changes in the NC/p1 cleavage site at codon 435 or 438 as was revealed during <it>in vitro </it>evolution experiments. These changes not only restored RC but also reduced PI resistance levels. Furthermore these changes normalized Gag processing efficiency and obstructed the novel secondary cleavage site observed for the double NC/p1 mutant.</p> <p>Conclusions</p> <p>The results of this study clearly demonstrate that HIV-1 can modulate Gag processing and thereby PI resistance. Distinct increases in Gag cleavage and PI resistance result in a reduced RC that can only be restored by amino acid changes in NC/p1 which reduce Gag processing to an optimal rate.</p

Re-valuation of annual cytology using HPV self-sampling to upgrade prevention (REACH UP): A feasibility study in women living with HIV in the UK

Introduction: Current UK guidelines for cervical cancer screening are based on the assumption that most women living with HIV (WLWH) are also high-risk (HR) human papillomavirus (HPV)-positive. We aimed to provide data on prevalence of HR-HPV in WLWH in the UK and to assess feasibility and acceptability of HR-HPV self-sampling in this group. // Methods: Women living with HIV attending six HIV services in London/south of England, with no history of cervical cancer, were enrolled. Participants self-collected a vaginal swab for the detection of HR-HPV, completed a survey about sexual/gynaecological history, attitudes towards annual screening and perception of HR-HPV self-sampling, and were asked to have their annual cervical smear. // Results: In all, 67 women were included: 86.5% were of black ethnicity, the median (range) age was 47 (24–60) years, median CD4 T-cell count was 683 cells/µL [interquartile range (IQR): 527–910], and 95.4% had viral load ≤ 50 copies/mL. All performed the vaginal swab. Eighteen (27%) had no cervical smear results; none of these women attended HIV services where this was routinely offered. No cervical samples were positive for HR-HPV. Three-quarters (75.8%) of participants reported adherence to annual screening, with only one woman (1.5%) attending irregularly. On visual analogue scales (from 0 to 100), median (IQR) acceptability and necessity of smear tests were 100 (75–100) and 100 (85–100), respectively. // Conclusions: Our results suggest that the prevalence of HR-HPV in WLWH in the UK may be low. Self-sampling seems to be acceptable, suggesting, if validated, its potential role in supporting less frequent smear testing and improving screening uptake in WLW

Hepatitis B virus infection as a neglected tropical disease

PCM is funded by a Wellcome Trust Intermediate Fellowship Grant (ref 110110/Z/15/Z).Publisher PDFPeer reviewe

Genomic surveillance of Escherichia coli and Klebsiella spp. in hospital sink drains and patients

Escherichia coli and Klebsiella spp. are important human pathogens that cause a wide spectrum of clinical disease. In healthcare settings, sinks and other wastewater sites have been shown to be reservoirs of antimicrobial-resistant E. coli and Klebsiella spp., particularly in the context of outbreaks of resistant strains amongst patients. Without focusing exclusively on resistance markers or a clinical outbreak, we demonstrate that many hospital sink drains are abundantly and persistently colonised with diverse populations of E. coli, Klebsiella pneumoniae and Klebsiella oxytoca, including both antimicrobial-resistant and susceptible strains. Using whole genome sequencing (WGS) of 439 isolates, we show that environmental bacterial populations are largely structured by ward and sink, with only a handful of lineages, such as E. coli ST635, being widely distributed, suggesting different prevailing ecologies which may vary as a result of different inputs and selection pressures. WGS of 46 contemporaneous patient isolates identified one (2%; 95% CI 0.05-11%) E. coli urine infection-associated isolate with high similarity to a prior sink isolate, suggesting that sinks may contribute to up to 10% of infections caused by these organisms in patients on the ward over the same timeframe. Using metagenomics from 20 sink-timepoints, we show that sinks also harbour many clinically relevant antimicrobial resistance genes including blaCTX-M, blaSHV and mcr, and may act as niches for the exchange and amplification of these genes. Our study reinforces the potential role of sinks in contributing to Enterobacterales infection and antimicrobial resistance in hospital patients, something that could be amenable to intervention

Hepatitis B virus infection as a neglected tropical disease

PCM is funded by a Wellcome Trust Intermediate Fellowship Grant (ref 110110/Z/15/Z).Publisher PDFPeer reviewe