SARS-CoV-2 rapidly evolves lineage-specific phenotypic differences when passaged repeatedly in immune-naïve mice.

The persistence of SARS-CoV-2 despite the development of vaccines and a degree of herd immunity is partly due to viral evolution reducing vaccine and treatment efficacy. Serial infections of wild-type (WT) SARS-CoV-2 in Balb/c mice yield mouse-adapted strains with greater infectivity and mortality. We investigate if passaging unmodified B.1.351 (Beta) and B.1.617.2 (Delta) 20 times in K18-ACE2 mice, expressing the human ACE2 receptor, in a BSL-3 laboratory without selective pressures, drives human health-relevant evolution and if evolution is lineage-dependent. Late-passage virus causes more severe disease, at organism and lung tissue scales, with late-passage Delta demonstrating antibody resistance and interferon suppression. This resistance co-occurs with a de novo spike S371F mutation, linked with both traits. S371F, an Omicron-characteristic mutation, is co-inherited at times with spike E1182G per Nanopore sequencing, existing in different within-sample viral variants at others. Both S371F and E1182G are linked to mammalian GOLGA7 and ZDHHC5 interactions, which mediate viral-cell entry and antiviral response. This study demonstrates SARS-CoV-2's tendency to evolve with phenotypic consequences, its evolution varying by lineage, and suggests non-dominant quasi-species contribution.

The Three W's of Acetaminophen In Children: Who, Why, and Which Administration Mode.

Acetaminophen is one of the oldest medications commonly administered in children. Its efficacy in treating fever and pain is well accepted among clinicians. However, the available evidence supporting the use of acetaminophen's different modes of administration remains relatively scarce and poorly known. This short report summarizes the available evidence and provides a framework to guide clinicians regarding a rational use of acetaminophen in children.

A small number of early introductions seeded widespread transmission of SARS-CoV-2 in Québec, Canada.

BACKGROUND: Québec was the Canadian province most impacted by COVID-19, with 401,462 cases as of September 24th, 2021, and 11,347 deaths due mostly to a very severe first pandemic wave. In April 2020, we assembled the Coronavirus Sequencing in Québec (CoVSeQ) consortium to sequence SARS-CoV-2 genomes in Québec to track viral introduction events and transmission within the province. METHODS: Using genomic epidemiology, we investigated the arrival of SARS-CoV-2 to Québec. We report 2921 high-quality SARS-CoV-2 genomes in the context of > 12,000 publicly available genomes sampled globally over the first pandemic wave (up to June 1st, 2020). By combining phylogenetic and phylodynamic analyses with epidemiological data, we quantify the number of introduction events into Québec, identify their origins, and characterize the spatiotemporal spread of the virus. RESULTS: Conservatively, we estimated approximately 600 independent introduction events, the majority of which happened from spring break until 2 weeks after the Canadian border closed for non-essential travel. Subsequent mass repatriations did not generate large transmission lineages (> 50 sequenced cases), likely due to mandatory quarantine measures in place at the time. Consistent with common spring break and "snowbird" destinations, most of the introductions were inferred to have originated from Europe via the Americas. Once introduced into Québec, viral lineage sizes were overdispersed, with a few lineages giving rise to most infections. Consistent with founder effects, the earliest lineages to arrive tended to spread most successfully. Fewer than 100 viral introductions arrived during spring break, of which 7-12 led to the largest transmission lineages of the first wave (accounting for 52-75% of all sequenced infections). These successful transmission lineages dispersed widely across the province. Transmission lineage size was greatly reduced after March 11th, when a quarantine order for returning travellers was enacted. While this suggests the effectiveness of early public health measures, the biggest transmission lineages had already been ignited prior to this order. CONCLUSIONS: Combined, our results reinforce how, in the absence of tight travel restrictions or quarantine measures, fewer than 100 viral introductions in a week can ensure the establishment of extended transmission chains.

Recurrent somatic BRAF insertion (p.V504_R506dup): a tumor marker and a potential therapeutic target in pilocytic astrocytoma.

Pilocytic astrocytoma (PA) is emerging as a tumor entity with dysregulated RAS/RAF/MEK/ERK signaling. In this study, we report the identification of a novel recurrent BRAF insertion (p.V504_R506dup) in five PA cases harboring exclusively this somatic tandem duplication. This recurrent alteration leads to an addition of three amino acids in the kinase domain of BRAF and has functional impact on activating MAPK phosphorylation. Importantly, we show that this mutation confers resistance to RAF inhibitors without changing effectiveness while downstream MEK inhibitors remain effective. Our results further emphasize the importance of BRAF alterations in PA and the need to characterize them in a given tumor as this can affect therapeutic strategies and their potential use as tumor marker in molecular diagnostics.

Digital health, gender and health equity: invisible imperatives.

A growing body of evidence shows the use of digital technologies in health-referred to as eHealth, mHealth or 'digital health'-is improving and saving lives in low- and middle-income countries. Despite this prevalent and persistent narrative, very few studies examine its effects on health equity, gender and power dynamics. This journal supplement addresses these invisible imperatives by going beyond traditional measures of coverage, efficacy and cost-effectiveness associated with digital health interventions, to unpack different experiences of health workers and beneficiaries. The collection of papers presents findings from a cohort of implementation research projects in Africa, Asia, Latin America and the Middle East, and two commentaries offer observations from learning-oriented evaluative activities across the entire cohort. The story emerging from this cohort is comprised of three themes: (i) digital health can positively influence health equity; (ii) gender and power analyses are essential; and (iii) digital health can be used to strengthen upward and downward accountability. These findings, at the individual project level and at the level of the cohort, provide encouraging recommendations on how to approach the design, implementation and evaluation of digital health interventions to address the Sustainable Development Goals agenda of leaving no one behind.

The change-makers of West Africa.

West Africa was the focus of global attention during the Ebola virus disease outbreak, when systemic health system weaknesses compounded a serious emergency and complicated response efforts. Following the crisis, calls were made to strengthen health systems, but investments to date have fallen short of delivering the support needed to build strong health systems able to prevent and manage future outbreaks.In part, this reality serves to highlight the shortcomings of the solutions being repeatedly prioritised by external funders and experts, solutions that often fail to consider the wealth of West African evidence and actors actively working to strengthen the leadership and health systems needed to drive and sustainably improve national health outcomes. Unfortunately, this knowledge and experience are rarely heard in the global arena.This journal supplement is a contribution, although small, to changing this practice by putting the perspectives, experiences and knowledge of West Africans on the table. It presents findings from a series of research and capacity development projects in West Africa funded by the International Development Research Centre's Maternal and Child Health programme (formerly Governance for Equity in Health Systems).The evidence presented here centres around two key themes. First, the theme that context matters. The evidence shows how context can change the shape of externally imposed interventions or policies resulting in unintended outcomes. At the same time, it highlights evidence showing how innovative local actors are developing their own approaches, usually low-cost and embedded in the context, to bring about change. Second, the collection of articles discusses the critical need to overcome the existing fragmentation of expertise, knowledge and actors, and to build strong working relationships amongst all actors so they can effectively work together to identify priority issues that can realistically be addressed given the available windows of opportunity.Vibrant West African-led collaborations amongst researchers, decision-makers and civil society, which are effectively supported by national, regional and global funding, need to foster, strengthen and use locally-generated evidence to ensure that efforts to strengthen health systems and improve regional health outcomes are successful. The solutions are clearly not to be found in the 'travelling models' of standardised interventions.

The fallacy of coverage: uncovering disparities to improve immunization rates through evidence. Results from the Canadian International Immunization Initiative Phase 2 - Operational Research Grants.

Immunization can and does save lives. However, the presence of vaccines does not easily translate into every child being vaccinated, and this is what the studies in this journal supplement reveal. From South Asia to West Africa,the evidence presented here reveals what we are calling the fallacy of coverage, going beyond uncovering the real vaccination rates to providing evidence on the reasons for the lack of effective coverage.The evidence for the fallacy of coverage is part of an operational research program entitled the Canadian International Immunization Initiative Phase 2 (CIII2). Through a competitive peer review process, six research grants were awarded to increase access to and enhance immunization services. This journal supplement provides a forum for the presentation of the results of five of the six studies.The story of the fallacy of coverage is made up of five theme areas of evidence - timeliness of immunization, social and gender inequities, vaccine efficacy, understanding demand side issues to tailor interventions, and national data sets masking actual district level coverage rates - that reveal the discrepancies in immunization coverage rates and the reasons behind these discrepancies. As part of the story, and to turn around the fallacy of coverage, the studies also provide proof of effective and locally relevant solutions.Policies and funding, while keeping an eye on future diseases, clearly need to maintain and increase support to address existing vaccine-preventable diseases to increase coverage such that by 2015 we can achieve 90% national vaccination coverage and reach the MDG of reducing mortality rates among children under five by two-thirds.The results from the operational research grants of the CIII2 offer some answers on how to reach this goal by demonstrating how locally generated evidence can inform immunization strategies to ensure that children who need to get vaccinated will get vaccinated, and vaccinated on time.

Comparison of crystal structures of human type 3 3alpha-hydroxysteroid dehydrogenase reveals an "induced-fit" mechanism and a conserved basic motif involved in the binding of androgen.

The aldo-keto reductase (AKR) human type 3 3alpha-hydroxysteroid dehydrogenase (h3alpha-HSD3, AKR1C2) plays a crucial role in the regulation of the intracellular concentrations of testosterone and 5alpha-dihydrotestosterone (5alpha-DHT), two steroids directly linked to the etiology and the progression of many prostate diseases and cancer. This enzyme also binds many structurally different molecules such as 4-hydroxynonenal, polycyclic aromatic hydrocarbons, and indanone. To understand the mechanism underlying the plasticity of its substrate-binding site, we solved the binary complex structure of h3alpha-HSD3-NADP(H) at 1.9 A resolution. During the refinement process, we found acetate and citrate molecules deeply engulfed in the steroid-binding cavity. Superimposition of this structure with the h3alpha-HSD3-NADP(H)-testosterone/acetate ternary complex structure reveals that one of the mobile loops forming the binding cavity operates a slight contraction movement against the citrate molecule while the side chains of many residues undergo numerous conformational changes, probably to create an optimal binding site for the citrate. These structural changes, which altogether cause a reduction of the substrate-binding cavity volume (from 776 A(3) in the presence of testosterone/acetate to 704 A(3) in the acetate/citrate complex), are reminiscent of the "induced-fit" mechanism previously proposed for the aldose reductase, another member of the AKR superfamily. We also found that the replacement of residues Arg(301) and Arg(304), localized near the steroid-binding cavity, significantly affects the 3alpha-HSD activity of this enzyme toward 5alpha-DHT and completely abolishes its 17beta-HSD activity on 4-dione. All these results have thus been used to reevaluate the binding mode of this enzyme for androgens.

De novo infection and serial transmission of Kaposi's sarcoma-associated herpesvirus in cultured endothelial cells.

Infection by Kaposi's sarcoma-associated herpesvirus (KSHV) is central to the pathogenesis of the endothelial neoplasm Kaposi's sarcoma (KS) and is also linked to the rare B-cell tumor known as primary effusion lymphoma (PEL). Latently infected PEL cell lines can be induced to enter the lytic cycle and produce KSHV virions. However, such cells do not support de novo infection or serial propagation of KSHV. These limitations have prevented the development of systems for the genetic analysis of KSHV and have impeded a deeper understanding of KS pathogenesis. Here we show that human dermal microvascular endothelial cells immortalized by expression of telomerase can be readily infected by KSHV virions produced by PEL cells. Infection is predominantly latent, but a small subpopulation enters the lytic cycle spontaneously. Phorbol ester (tetradecanoyl phorbol acetate [TPA]) treatment of latently infected cells leads to enhanced induction of lytic KSHV replication, resulting in foci of cytopathic effect. There is no cytopathic effect or viral DNA expansion when infected TIME cells (telomerase-immortalized microvascular endothelial cells) are TPA induced in the presence of phosphonoacetic acid (PAA), an inhibitor of herpesvirus replication. Supernatants from phorbol-induced cultures transfer latent KSHV infection to uninfected cells, which can likewise be induced to undergo lytic replication by TPA treatment, and the virus can be further serially transmitted. Serial passage of the virus in TIME cells is completely inhibited when TPA treatment is done in the presence of PAA. Latently infected endothelial cells do not undergo major morphological changes or growth transformation, and infection is lost from the culture upon serial passage. This behavior faithfully recapitulates the behavior of spindle cells explanted from primary KS biopsies, strongly supporting the biological relevance of this culture system. These findings suggest that either the stability or the growth-deregulatory potential of the KSHV latency program in endothelial cells is more limited than might be predicted by analogy with other oncogenic viruses.