3,444 research outputs found
HIV transmission in part of the US prison system: implications for Europe.
A study in the United States has shown that HIV transmission has been occurring within the prison system in the state of Georgia.</jats:p
THE ROLE OF THE VAGINAL MICROBIOME IN HPV INFECTION AND CARCINOGENESIS
THE ROLE OF THE VAGINAL MICROBIOME IN HPV INFECTION AND CARCINOGENESIS by Alessandra Christina Gill Cervical cancer is one of the most common cancers affecting women worldwide and is caused by persistent infection with high-risk types of human papillomavirus (HR- HPV). Cervical cancer rates are particularly high in developing regions, including South Africa, which currently also has the highest HIV prevalence anywhere in the world. The immunosuppression associated with HIV infection results in an increased likelihood of persistent HR-HPV infection in HIV-positive women, resulting in an increased risk of progression to cervical cancer, a risk that increases as HIV infection progresses. Another risk factor for HR-HPV infection is a condition called bacterial vaginosis (BV) which is typified by a vaginal microbiome (VMB) made up of a diverse array of anaerobic bacteria with low numbers of lactobacilli. However, little detail is known about the bacterial species that are involved and the mechanisms that underlie this association. Using samples collected by the HARP (HPV in Africa Research Partnership) study, which was coordinated by the London School of Hygiene and Tropical Medicine, this study aimed to determine the association between the type of VMB and high-risk HPV infection and the presence of precancerous lesions of the cervix in HIV-infected South African women. This was achieved by characterising the VMB with the help of 16S rRNA gene sequencing of the V3-V4 region on the Illumina HiSeq platform, allowing identification of the bacterial taxa present in each vaginal sample. Laboratory and computational methods were optimised prior to sequencing of clinical samples to optimise the information gained. We were able to determine that samples collected during the HARP study in the fixative medium BoonFixÂź and stored at room temperature were suitable for microbiome analysis. Furthermore, when using the Qiagen Blood and Tissue Kit, the inclusion of the collected vaginal swab in the proteinase K digestion step significantly increased DNA yield, which was correlated with lower levels of contaminant reads in the sequencing results. In order to further refine the sequencing results, we tested two newer OTU clustering methods (DADA2 and Swarm) against USEARCH and were able to show that newer methods allow better ii species separation than those (such as USEARCH) that rely on a similarity threshold. We found that this population of HIV-positive South African women had VMB profiles typical for women with black ethnic background and HIV infection: the majority had a Lactobacillus iners-dominated community, had a microbiome consisting of a diverse mixture of anaerobes typically associated with BV, or lay somewhere between these two extremes having lower levels of L. iners together with BV-associated anaerobes. In contrast, community types dominated by L. crispatus, L. jensenii, Gardnerella vaginalis, Atopobium vaginae or Bifidobacterium spp., or containing a relatively high abundance of pathobionts such as streptococci, staphylococci or Enterobacteriaceae, were uncommon or rare. Our results provide evidence for an association between HR-HPV infection and a high diversity vaginal microbiota typical of BV with a paucity of lactobacilli in general but especially L. crispatus. However, the effect sizes were relatively small in comparison to other studies, which may be due to the fact that our entire study population was HIV- positive: these women had a high baseline prevalence of non-lactobacilli-dominated VMBs (43% had a Nugent score of 7-10) and were more vulnerable to acquisition and persistence of pathogens (due to a median CD4 count of only 428 cells/ÎŒl) than HIV-negative women in the general population. In multivariable models, we found no evidence of an association between the VMB and histological precancerous changes of the cervix in this cohort, beyond that related to persistent HR-HPV infection. The results of this study suggest that a high diversity vaginal microbiome with a paucity of lactobacilli is associated with HR-HPV infection in HIV-positive women and highlight the importance of taking HIV status into account when researching the VMB in HR-HPV infection and associated precancerous changes. A better understanding of how the vaginal microbiome impacts on the natural history of HPV infection and cervical cancer in women living with HIV could ultimately lead to improved management and treatment of these conditions in this high-risk group
What Makes a Terrorist? Muslimsâ and non-Muslimsâ Lay Perceptions of Risk Factors and Their Consequences for Counter-terrorism Policy Support
The question of why people become terrorists has preoccupied scholars and policy makers for decades. Yet, very little is known about how lay people perceive individuals at risk of becoming terrorists. In two studies conducted in the U.K., we aimed to fill this gap. Study 1 showed that Muslims and non-Muslims perceived a potential minority-group terrorist in terms of both structural (e.g., life-history, social) and individual risk factors (e.g., personality, psychopathology, ideology). In Study 2, Muslims and non-Muslims perceived a potential right-wing majority-group terrorist as having more individual predispositions to terrorism than a potential left-wing majority-group terrorist. Importantly, in both studies, individualist perceptions such as psychopathology were positively associated with support for stricter law enforcement, whereas structuralist perceptions such as adverse childhood experiences were positively associated with support for social interventions. Lay people seem to have multifactorial understandings of individuals at risk of becoming terrorists, which influence their counter-terrorism policy support
Review article: emerging insights into the immunopathology, clinical and therapeutic aspects of hepatitis delta virus
BACKGROUND: Hepatitis delta virus (HDV), which causes the most severe form of viral hepatitis, is an obligated hepatitis B (HBV) satellite virus that can either infect naĂŻve subjects simultaneously with HBV (coâinfection), or chronically infect HBV carriers (superâinfection). An estimated 12 million people are infected by HDV worldwide. AIMS: To summarise the most relevant aspects of the molecular biology of HDV, and to discuss the latest understanding of the induced pathology, interactions with the immune system, as well as both approved and investigational treatment options. METHODS: References for this review were identified through searches of PubMed with the terms âHDVâ âviral hepatitisâ âcoâinfectionâ and âsuperâinfection,â published between 1980 and October 2021 RESULTS: The limited access to the HDVâinfected liver has hampered the investigation of the intrahepatic compartment and our understanding of the mechanisms of HDV pathogenesis. In the absence of standardised and sensitive diagnostic tools, HDV is often underdiagnosed and owing to its strong dependence on host cellular factors, the development of direct antiviral agents has been challenging. New therapeutic agents targeting different steps of the viral cycle have recently been investigated, among which bulevirtide (which was conditionally approved by EMA in July 2020) and lonafarnib; both drugs having received orphan drug designation from both the EMA and FDA. CONCLUSIONS: The HBV cure programme potentially offers a unique opportunity to enhance HDV treatment strategies. In addition, a more comprehensive analysis of the intrahepatic compartment is mandated to better understand any liverâconfined interaction of HDV with the host immune system
Single Versus Multiâvisit Endodontic Treatment of Teeth with Apical Periodontitis: An In vivo Study with 1âyear Evaluation
Background: Apical periodontitis (AP) is one of the most prevalent diseases of the teeth. Treatment of AP is based on the removal of the cause, i.e., bacteria from the root canals. Achievement of adequate bacterial eradication in one appointment treatment remains a controversy.Aim: This prospective study was conducted with the objective to compare the periapical healing of teeth with AP treated in (a) single visit versus (b) two visits, either with or without Vitapex as an intracanal medicament.Subjects and Methods: Patients were selected randomly from the Department of Conservative Dentistry and Endodontics. Fortyâthree patients (81 teeth) met the inclusion criteria, i.e., AP (both symptomatic and asymptomatic) visible radiographically size â„2 mm Ă 2 mm, not suffering from any immuneâcompromising disease, age between 16 and 65 years and tooth not accessed previously. Patients were randomly divided into three groups, i.e., singleâvisit group (Group 1), multiâvisit group without any intracanal medicament (Group 2), and multiâvisit group with Vitapex as interim intracanal medicament (Group 3). Comparison was done radiographically using periapical index (PAI). The primary outcome measure was the change in periapical radiolucency after 1 year assessed by PAI scores. The MannâWhitney Uâtest was used to evaluate differences between groups at baseline (immediate postoperative) and at the 12âmonth followâup evaluation. Change in PAI score for each group from baseline to 12âmonth followâup evaluation was tested with the Wilcoxon signed rank test. The secondary outcome measures, proportion of teeth in each group that could be considered improved (decreased PAI score) or healed (PAI <2), were assessed with the Chiâsquare test.Results: No statistically significant difference in periapical healing was found between three groups.Conclusion: After 1âyear evaluation, no difference in periapical healing was found between singleâvisit treatment and multiâvisit treatment groups with the given sample size.Keywords: 1âyear evaluation, Apical periodontitis, Multiâvisit treatment, Single visit, Vitape
Using and communicating uncertainty for the effective control of invasive non-native species
Estimates of quantities needed to plan invasive species control, such as population size, are always uncertain; this is an issue that can become a problem when mishandled in ecological science and its communication. The complexities of incorporating uncertainty into sophisticated decisionâsupport tools may be a barrier to their use by decision makers, leading to decisions being made without due regard to uncertainty and risking misplaced certainty of predicted outcomes. We summarise ways in which uncertainty has been incorporated into and used to advise decisions on the management of invasive nonânative species and other problem species, and offer a simple conceptual model for accommodating and using uncertainty at the planning stage. We also demonstrate how frequently uncertainty has been misused and miscommunicated in the wildlife management literature. We contend that uncertainty in estimates of natural quantities must be acknowledged, can inform decisions and can be made to derive decisions, and should not be ignored if invasive species policy is to be delivered effectively. Uncertainty must be communicated thoroughly and correctly by scientists if decision makers are to understand its consequences for planning and resourcing control programmes
Molecular Characterization of Two Monoclonal Antibodies against the Same Epitope on B-Cell Receptor Associated Protein 31
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How does it feel to be a problem? Patients' experiences of self-management support in New Zealand and Canada
Published source must be acknowledgedPublishe
Use of Bayesian inference for parameter recovery in DC and AC voltammetry
We describe the use of Bayesian inference for quantitative comparison of voltammetric methods for investigating electrode kinetics. We illustrate the utility of the approach by comparing the information content in both DC and AC voltammetry at a planar electrode for the case of a quasi-reversible one electron reaction mechanism. Using synthetic data (i. e. simulated data based on Butler-Volmer electrode kinetics for which the true parameter values are known and to which realistic levels of simulated experimental noise have been added), we are able to show that AC voltammetry is less affected by experimental noise (so that in effect it has a greater information content then the corresponding DC measurement) and hence yields more accurate estimates of the experimental parameters for a given level of noise. Significantly, the AC approach is shown to be able to distinguish higher values of the rate constant. The results of using synthetic data are then confirmed for an illustrative case of experimental data for the [Fe(CN)6]3â/4âprocess
Individual repeatability of avian migration phenology: a systematic review and meta-analysis
Changes in phenology and distribution are being widely reported for many migratory species in response to shifting environmental conditions. Understanding these changes and the situations in which they occur can be aided by understanding consistent individual differences in phenology and distribution and the situations in which consistency varies in strength or detectability. Studies tracking the same individuals over consecutive years are increasingly reporting migratory timings to be a repeatable trait, suggesting that flexible individual responses to environmental conditions may contribute little to population-level changes in phenology and distribution. However, how this varies across species and sexes, across the annual cycle and in relation to study (tracking method, study design) and/or ecosystem characteristics is not yet clear. Here, we take advantage of the growing number of publications in movement ecology to perform a phylogenetic multilevel meta-analysis of repeatability estimates for avian migratory timings to investigate these questions. Of 2,433 reviewed studies, 54 contained suitable information for meta-analysis, resulting in 177 effect sizes from 47 species. Individual repeatability of avian migratory timings averaged 0.414 (95% confidence interval: 0.3-0.5) across landbirds, waterbirds and seabirds, suggesting consistent individual differences in migratory timings is a common feature of migratory systems. Timing of departure from the non-breeding grounds was more repeatable than timings of arrival at or departure from breeding grounds, suggesting that conditions encountered on migratory journeys and outcome of breeding attempts can influence individual variation. Population-level shifts in phenology could arise through individual timings changing with environmental conditions and/or through shifts in the numbers of individuals with different timings. Our findings suggest that, in addition to identifying the conditions associated with individual variation in phenology, exploring the causes of between-individual variation will be key in predicting future rates and directions of changes in migratory timings. We therefore encourage researchers to report the within- and between- individual variance components underpinning the reported repeatability estimates to aid interpretation of migration behaviour. In addition, the lack of studies in the tropics means that levels of repeatability in less strongly seasonal environments are not yet clear
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