Molecular Epidemiology of Human Immunodeficiency Virus Type 1 Sub-Subtype A3 in Senegal from 1988 to 2001

The global human immunodeficiency virus (HIV)epidemic is characterized by significant genetic diversity in circulating viruses. We have recently characterized a group of viruses that form a distinct sub-subtype within the subtype A radiation, which we have designated HIV type 1 (HIV-1) sub-subtype A, circulating in West Africa. A prospective study of a cohort of female sex workers (FSW) in Dakar, Senegal over an 18-year period indicated that an A3-specific sequence in the C2-V3 region of the env gene was found in 46 HIV-1-infected women. HIV-1 sub-subtype A3 appeared in the FSW population as early as 1988 and continued to be transmitted as of 2001. We also found that HIV-1 A3 is not confined to the FSW cohort in Senegal but is also circulating in the general population in Dakar. Furthermore, analyses of viral sequences from a few other West and Central African countries also demonstrated evidence of HIV-1 A3 sequence in isolates from HIV-1-infected people in Ivory Coast, Nigeria, Niger, Guinea Bissau, Benin, and Equatorial Guinea. Overall, because of the evidence of sub-subtype A3 in the general population in Senegal, as well as in a few neighboring West and Central African countries, along with the increasing incidence of infection with A3-containing viruses in the Dakar high-risk FSW population, we feel that HIV-1 sub-subtype A3 viruses are important to distinguish and monitor

A modified anthrax toxin-based enzyme-linked immunospot assay reveals robust T cell responses in symptomatic and asymptomatic Ebola virus exposed individuals

Background Ebola virus (EBOV) caused more than 11,000 deaths during the 2013–2016 epidemic in West Africa without approved vaccines or immunotherapeutics. Despite its high lethality in some individuals, EBOV infection can produce little to no symptoms in others. A better understanding of the immune responses in individuals who experienced minimally symptomatic and asymptomatic infection could aid the development of more effective vaccines and antivirals against EBOV and related filoviruses. Methodology/Principle findings Between August and November 2017, blood samples were collected from 19 study participants in Lagos, Nigeria, including 3 Ebola virus disease (EVD) survivors, 10 individuals with documented close contact with symptomatic EVD patients, and 6 control healthcare workers for a cross-sectional serosurvey and T cell analysis. The Lagos samples, as well as archived serum collected from healthy individuals living in surrounding areas of the 1976 Democratic Republic of Congo (DRC) epidemic, were tested for EBOV IgG using commercial enzyme-linked immunosorbent assays (ELISAs) and Western blots. We detected antibodies in 3 out of 3 Lagos survivors and identified 2 seropositive individuals not known to have ever been infected. Of the DRC samples tested, we detected antibodies in 9 out of 71 (12.7%). To characterize the T cell responses in the Lagos samples, we developed an anthrax toxin-based enzyme-linked immunospot (ELISPOT) assay. The seropositive asymptomatic individuals had T cell responses against EBOV nucleoprotein, matrix protein, and glycoprotein 1 that were stronger in magnitude compared to the survivors. Conclusion/Significance Our data provide further evidence of EBOV exposure in individuals without EVD-like illness and, for the first time, demonstrate that these individuals have T cell responses that are stronger in magnitude compared to severe cases. These findings suggest that T cell immunity may protect against severe EVD, which has important implications for vaccine development

Modelling the relationship between malaria prevalence as a measure of transmission and mortality across age groups

Parasite prevalence has been used widely as a measure of malaria transmission, especially in malaria endemic areas. However, its contribution and relationship to malaria mortality across different age groups has not been well investigated. Previous studies in a health and demographic surveillance systems (HDSS) platform in western Kenya quantified the contribution of incidence and entomological inoculation rates (EIR) to mortality. The study assessed the relationship between outcomes of malaria parasitaemia surveys and mortality across age groups.; Parasitological data from annual cross-sectional surveys from the Kisumu HDSS between 2007 and 2015 were used to determine malaria parasite prevalence (PP) and clinical malaria (parasites plus reported fever within 24 h or temperature above 37.5 °C). Household surveys and verbal autopsy (VA) were used to obtain data on all-cause and malaria-specific mortality. Bayesian negative binomial geo-statistical regression models were used to investigate the association of PP/clinical malaria with mortality across different age groups. Estimates based on yearly data were compared with those from aggregated data over 4 to 5-year periods, which is the typical period that mortality data are available from national demographic and health surveys.; Using 5-year aggregated data, associations were established between parasite prevalence and malaria-specific mortality in the whole population (RR; malaria; = 1.66; 95% Bayesian Credible Intervals: 1.07-2.54) and children 1-4 years (RR; malaria; = 2.29; 1.17-4.29). While clinical malaria was associated with both all-cause and malaria-specific mortality in combined ages (RR; all-cause; = 1.32; 1.01-1.74); (RR; malaria; = 2.50; 1.27-4.81), children 1-4 years (RR; all-cause; = 1.89; 1.00-3.51); (RR; malaria; = 3.37; 1.23-8.93) and in older children 5-14 years (RR; all-cause; = 3.94; 1.34-11.10); (RR; malaria; = 7.56; 1.20-39.54), no association was found among neonates, adults (15-59 years) and the elderly (60+ years). Distance to health facilities, socioeconomic status, elevation and survey year were important factors for all-cause and malaria-specific mortality.; Malaria parasitaemia from cross-sectional surveys was associated with mortality across age groups over 4 to 5 year periods with clinical malaria more strongly associated with mortality than parasite prevalence. This effect was stronger in children 5-14 years compared to other age-groups. Further analyses of data from other HDSS sites or similar platforms would be useful in investigating the relationship between malaria and mortality across different endemicity levels

The Physics of the B Factories

This work is on the Physics of the B Factories. Part A of this book contains a brief description of the SLAC and KEK B Factories as well as their detectors, BaBar and Belle, and data taking related issues. Part B discusses tools and methods used by the experiments in order to obtain results. The results themselves can be found in Part C

Search for light bosons in decays of the 125 GeV Higgs boson in proton-proton collisions at root s=8 TeV

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Search for heavy gauge W ' bosons in events with an energetic lepton and large missing transverse momentum at root s=13TeV

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Measurement of differential cross sections for top quark pair production using the lepton plus jets final state in proton-proton collisions at 13 TeV

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A search for new phenomena in pp collisions at root s=13TeV in final states with missing transverse momentum and at least one jet using the alpha(T) variable

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Search for supersymmetry in the all-hadronic final state using top quark tagging in pp collisions at root s=13 TeV

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