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HIV prevention research and COVID-19: putting ethics guidance to the test
Background
Critical public health measures implemented to mitigate the spread of the novel coronavirus disease (COVID-19) pandemic have disrupted health research worldwide, including HIV prevention research. While general guidance has been issued for the responsible conduct of research in these challenging circumstances, the contours of the dueling COVID-19 and HIV/AIDS pandemics raise some critical ethical issues for HIV prevention research. In this paper, we use the recently updated HIV Prevention Trials Network (HPTN) Ethics Guidance Document (EGD) to situate and analyze key ethical challenges related to the conduct of HIV prevention research during the COVID-19 pandemic as well as identify potential areas for refinement of the guidance document based on this unprecedented state of affairs.
Main body
Necessary actions taken for HIV prevention research studies due to the COVID-19 pandemic involve an array of ethical issues including those related to: (1) risk mitigation; (2) behavior change; (3) compounding vulnerability; (4) community engagement; (5) trial reopening; and 6) shifting research priorities.
Conclusions
In the context of the dueling HIV and COVID-19 global pandemics, research teams and sponsors must be nimble in responding to the rapidly changing environment by being sensitive to the associated ethical issues. The HTPN EGD provides a rich set of tools to help identify, analyze and address many of these issues. At the same time, future refinements of the HPTN EGD and other research ethics guidance could be strengthened by providing explicit advice regarding the ethical issues associated with disrupted research and the reopening of studies. In addition, additional consideration should be given to appropriately balancing domains of risk (e.g., physical versus social), addressing the vulnerability of research staff and community partners, and responding to un-anticipatable ancillary care needs of participants and communities. Appropriately addressing these issues will necessitate conceptual work, which would benefit from the careful documentation of the actual ethical issues encountered in research, the strategies implemented to overcome them, and their success in doing so. Throughout all of these efforts, it is critical to remember that the HIV pandemic not be forgotten in the rush to deal with the COVID-19 pandemic
BronchUK:protocol for an observational cohort study and biobank in bronchiectasis
Bronchiectasis has been a largely overlooked disease area in respiratory medicine. This is reflected by a shortage of large-scale studies and lack of approved therapies, in turn leading to a variation of treatment across centres. BronchUK (Bronchiectasis Observational Cohort and Biobank UK) is a multicentre, prospective, observational cohort study working collaboratively with the European Multicentre Bronchiectasis Audit and Research Collaboration project. The inclusion criteria for patients entering the study are a clinical history consistent with bronchiectasis and computed tomography demonstrating bronchiectasis. Main exclusion criteria are 1) patients unable to provide informed consent, 2) bronchiectasis due to known cystic fibrosis or where bronchiectasis is not the main or co-dominant respiratory disease, 3) age <18 years, and 4) prior lung transplantation for bronchiectasis. The study is aligned to standard UK National Health Service (NHS) practice with an aim to recruit a minimum of 1500 patients from across at least nine secondary care centres. Patient data collected at baseline includes demographics, aetiology testing, comorbidities, lung function, radiology, treatments, microbiology and quality of life. Patients are followed up annually for a maximum of 5 years and, where able, blood and/or sputa samples are collected and stored in a central biobank. BronchUK aims to collect robust longitudinal data that can be used for analysis into current NHS practice and patient outcomes, and to become an integral resource to better inform future interventional studies in bronchiectasis
Biliary epithelium and liver B cells exposed to bacteria activate intrahepatic MAIT cells through MR1
Background & AimsMucosal-Associated Invariant T (MAIT) cells are innate-like T cells characterised by the invariant TCR-chain, Vα7.2-Jα33, and are restricted by MR1, which presents bacterial vitamin B metabolites. They are important for antibacterial immunity at mucosal sites; however, detailed characteristics of liver-infiltrating MAIT (LI-MAIT) and their role in biliary immune surveillance remain unexplored.MethodsThe phenotype and intrahepatic localisation of human LI-MAIT cells was examined in diseased and normal livers. MAIT cell activation in response to E. coli-exposed macrophages, biliary epithelial cells (BEC) and liver B cells was assessed with/without anti-MR1.ResultsIntrahepatic MAIT cells predominantly localised to bile ducts in the portal tracts. Consistent with this distribution, they expressed biliary tropic chemokine receptors CCR6, CXCR6, and integrin αEβ7. LI-MAIT cells were also present in the hepatic sinusoids and possessed tissue-homing chemokine receptor CXCR3 and integrins LFA-1 and VLA-4, suggesting their recruitment via hepatic sinusoids. LI-MAIT cells were enriched in the parenchyma of acute liver failure livers compared to chronic diseased livers. LI-MAIT cells had an activated, effector memory phenotype, expressed α4β7 and receptors for IL-12, IL-18, and IL-23. Importantly, in response to E. coli-exposed macrophages, liver B cells and BEC, MAIT cells upregulated IFN-γ and CD40 Ligand and degranulated in an MR1-dependent, cytokine-independent manner. In addition, diseased liver MAIT cells expressed T-bet and RORγt and the cytokines IFN-γ, TNF-α, and IL-17.ConclusionsOur findings provide the first evidence of an immune surveillance effector response for MAIT cells towards BEC in human liver; thus they could be manipulated for treatment of biliary disease in the future
Pelvic Chlamydial Infection Predisposes to Ectopic Pregnancy by Upregulating Integrin ?1 to Promote Embryo-tubal Attachment
Tubal ectopic pregnancies are a leading cause of global maternal morbidity and mortality. Previous infection with Chlamydia trachomatis is a major risk factor for tubal embryo implantation but the biological mechanism behind this association is unclear. Successful intra-uterine embryo implantation is associated with increased expression of endometrial “receptivity” integrins (cell adhesion molecules).We examined integrin expression in Fallopiantubes of women with previous C. trachomatis infection, in mice experimentally infected with C. trachomatis, in immortalised human oviductal epithelial cells (OE-E6/E7) and in an in vitro model of human embryo attachment (trophoblast spheroid-OE-E6/7 cell co-culture). Previous exposure with C. trachomatis increased Fallopian tube/oviduct integrin-subunit beta-1 (ITGB1) in women and mice compared to controls. C. trachomatis increased OEE6/E7 cell ITGB1 expression and promoted trophoblast attachment to OE-E6/E7 cellswhichwas negated by anti-ITGB1-antibody.We demonstrate that infection with C. trachomatis increases tubal ITGB1 expression, predisposing to tubal embryo attachment and ectopic pregnancy
A rotating white dwarf shows different compositions on its opposite faces
White dwarfs, the extremely dense remnants left behind by most stars after
their death, are characterised by a mass comparable to that of the Sun
compressed into the size of an Earth-like planet. In the resulting strong
gravity, heavy elements sink toward the centre and the upper layer of the
atmosphere contains only the lightest element present, usually hydrogen or
helium. Several mechanisms compete with gravitational settling to change a
white dwarf's surface composition as it cools, and the fraction of white dwarfs
with helium atmospheres is known to increase by a factor ~2.5 below a
temperature of about 30,000 K; therefore, some white dwarfs that appear to have
hydrogen-dominated atmospheres above 30,000 K are bound to transition to be
helium-dominated as they cool below it. Here we report observations of ZTF
J203349.8+322901.1, a transitioning white dwarf with two faces: one side of its
atmosphere is dominated by hydrogen and the other one by helium. This peculiar
nature is likely caused by the presence of a small magnetic field, which
creates an inhomogeneity in temperature, pressure or mixing strength over the
surface. ZTF J203349.8+322901.1 might be the most extreme member of a class of
magnetic, transitioning white dwarfs -- together with GD 323, a white dwarf
that shows similar but much more subtle variations. This new class could help
shed light on the physical mechanisms behind white dwarf spectral evolution.Comment: 45 pages, 11 figure
The Long-Baseline Neutrino Experiment: Exploring Fundamental Symmetries of the Universe
The preponderance of matter over antimatter in the early Universe, the
dynamics of the supernova bursts that produced the heavy elements necessary for
life and whether protons eventually decay --- these mysteries at the forefront
of particle physics and astrophysics are key to understanding the early
evolution of our Universe, its current state and its eventual fate. The
Long-Baseline Neutrino Experiment (LBNE) represents an extensively developed
plan for a world-class experiment dedicated to addressing these questions. LBNE
is conceived around three central components: (1) a new, high-intensity
neutrino source generated from a megawatt-class proton accelerator at Fermi
National Accelerator Laboratory, (2) a near neutrino detector just downstream
of the source, and (3) a massive liquid argon time-projection chamber deployed
as a far detector deep underground at the Sanford Underground Research
Facility. This facility, located at the site of the former Homestake Mine in
Lead, South Dakota, is approximately 1,300 km from the neutrino source at
Fermilab -- a distance (baseline) that delivers optimal sensitivity to neutrino
charge-parity symmetry violation and mass ordering effects. This ambitious yet
cost-effective design incorporates scalability and flexibility and can
accommodate a variety of upgrades and contributions. With its exceptional
combination of experimental configuration, technical capabilities, and
potential for transformative discoveries, LBNE promises to be a vital facility
for the field of particle physics worldwide, providing physicists from around
the globe with opportunities to collaborate in a twenty to thirty year program
of exciting science. In this document we provide a comprehensive overview of
LBNE's scientific objectives, its place in the landscape of neutrino physics
worldwide, the technologies it will incorporate and the capabilities it will
possess.Comment: Major update of previous version. This is the reference document for
LBNE science program and current status. Chapters 1, 3, and 9 provide a
comprehensive overview of LBNE's scientific objectives, its place in the
landscape of neutrino physics worldwide, the technologies it will incorporate
and the capabilities it will possess. 288 pages, 116 figure
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