Phylogenetic Incongruence in E. coli O104: Understanding the Evolutionary Relationships of Emerging Pathogens in the Face of Homologous Recombination

Escherichia coli O104:H4 was identified as an emerging pathogen during the spring and summer of 2011 and was responsible for a widespread outbreak that resulted in the deaths of 50 people and sickened over 4075. Traditional phenotypic and genotypic assays, such as serotyping, pulsed field gel electrophoresis (PFGE), and multilocus sequence typing (MLST), permit identification and classification of bacterial pathogens, but cannot accurately resolve relationships among genotypically similar but pathotypically different isolates. To understand the evolutionary origins of E. coli O104:H4, we sequenced two strains isolated in Ontario, Canada. One was epidemiologically linked to the 2011 outbreak, and the second, unrelated isolate, was obtained in 2010. MLST analysis indicated that both isolates are of the same sequence type (ST678), but whole-genome sequencing revealed differences in chromosomal and plasmid content. Through comprehensive phylogenetic analysis of five O104:H4 ST678 genomes, we identified 167 genes in three gene clusters that have undergone homologous recombination with distantly related E. coli strains. These recombination events have resulted in unexpectedly high sequence diversity within the same sequence type. Failure to recognize or adjust for homologous recombination can result in phylogenetic incongruence. Understanding the extent of homologous recombination among different strains of the same sequence type may explain the pathotypic differences between the ON2010 and ON2011 strains and help shed new light on the emergence of this new pathogen

Myelomonocytic Cell Lines in Modeling HIV-1 Infection of the Bone Marrow

Human immunodeficiency virus type 1 (HIV-1), the etiologic agent of acquired immunodeficiency syndrome (AIDS), primarily infects T cells and cells of the monocyte-macrophage lineage. This is due to the presence of the cell surface receptor CD4 and the coreceptors, CXCR4, and CCR5. While the T-cell has classically been the cell type associated with HIV-1 disease progression, cells of the monocyte-macrophage lineage have also been shown to play a major role in this viral pathologic process. Classically, this has involved monocytic cells in the peripheral blood and tissue macrophages, however, over the course of HIV disease, the promyelomonocytic cells of the bone marrow (BM) have also been shown to play a role in pathogenesis retroviral disease in that they play an integral role in the reseeding of the periphery and end-organ tissues. This has involved an initial infection of the bone marrow hematopoietic progenitor cells. Given this observation, over the years there have been a number of cell lines that have been developed and provided valuable insights into research questions surrounding HIV-1 infection of the monocyte-macrophage cell lineage. In this regard, we will examine the biological and immunological properties of these BM-derived cell lines with respect to their utility in exploring the pathogenesis of HIV-1 in humans

The Effectiveness of Behavioral Interventions in Adults with Post-Traumatic Stress Disorder during Clinical Rehabilitation: A Rapid Review

Background: This review examined the effectiveness of behavioral interventions for adults with post-traumatic stress disorder (PTSD) triggered by physical injury or medical trauma. It discusses implications in support of rehabilitation management for COVID-19 survivors diagnosed with PTSD. Methods: This study adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and the Interim Guidance from the Cochrane Rapid Reviews Methods Group. The authors searched for randomized control trials in PubMed, Embase, and CENTRAL databases up to 31 March 2021. Results: Five studies (n = 459) met the inclusion criteria. Each study measured a different comparison of interventions. The certainty of the evidence was judged to be very low for all outcomes. Post-traumatic stress disorder symptom reduction was found to be in favor of trauma-focused cognitive-behavioral therapy, cognitive therapy, and cognitive-behavioral therapy. Cognitive function improvements were observed in favor of the cognitive processing therapy control intervention. Conclusions: Overall, there is uncertainty about whether behavioral interventions are effective in reducing PTSD symptoms and improving functioning and quality of life when the disorder is triggered by a physical or medical trauma rather than a psychological trauma. Further research should investigate their efficacy in the context of rehabilitation management and gather evidence on this populatio

Phosphonium polymethacrylates for siRNA delivery: effect of polymer and RNA structural parameters on polyplex assembly and gene knockdown

Synthetic polymers containing quaternary phosphonium salts are an emerging class of materials for the delivery of oligo/polynucleotides. In this work, cationic phosphonium salt-containing polymethacrylates –and their corresponding ammonium analogues– were synthesized by RAFT polymerization. Both the nature of the charged heteroatom (N vs. P) and the length of the spacer separating the cationic units along the polymer backbone (oxyethylene vs. trioxyethylene) were systematically varied. Polymers efficiently bound siRNA at N+/P- or P+/P- ratios of 2 and above. At a 20:1 ratio, small polyplexes (Rh: 4-15 nm) suitable for cellular uptake were formed that displayed low cytotoxicity. Whilst siRNA polyplexes from both ammonium and phosphonium polymers were efficiently internalised by GFP-expressing 3T3 cells, no knockdown of GFP expression was observed. However, 65% Survivin gene knockdown was observed when short interfering RNA (siRNA) was replaced with novel, multimerised long interfering liRNA (liRNA) in HeLa cells, demonstrating the importance of RNA macromolecular architecture on RNA-mediated gene silencing

HIV-1 DNA/MVA vaccination reduces the per exposure probability of infection during repeated mucosal SHIV challenges

Historically, HIV vaccines specifically designed to raise cellular immunity resulted in protection from disease progression but not infection when tested in monkeys challenged with a single high virus exposure. An alternative approach, more analogous to human sexual exposures, is to repetitively challenge immunized monkeys with a much lower dose of virus until systemic infection is documented. Using these conditions to mimic human sexual transmission, we found that a multi-protein DNA/MVA HIV-1 vaccine is indeed capable of protecting rhesus monkeys against systemic infection when repeatedly challenged with a highly heterologous immunodeficiency virus (SHIV). Furthermore, this repetitive challenge approach allowed us to calculate per-exposure probability of infection, an observed vaccine efficacy of 64%, and undertake a systematic analysis for correlates of protection based on exposures needed to achieve infection. Therefore, improved non-human primate models for vaccine efficacy can provide novel insight and perhaps renew expectations for positive outcomes of human HIV clinical trials

Post‐diagnosis adiposity, physical activity, sedentary behaviour, dietary factors, supplement use and colorectal cancer prognosis: Global Cancer Update Programme ( CUP Global) summary of evidence grading

Based on the World Cancer Research Fund Global Cancer Update Programme, we performed systematic reviews and meta‐analyses to investigate the association of post‐diagnosis adiposity, physical activity, sedentary behaviour, and dietary factors with colorectal cancer prognosis. We searched PubMed and Embase until 28th February, 2022. An independent expert committee and expert panel graded the quality of evidence. A total of 167 unique publications were reviewed, and all but five were observational studies. The quality of the evidence was graded conservatively due to the high risk of several biases. There was evidence of non‐linearity in the associations between body mass index and colorectal cancer prognosis. The associations appeared reverse J‐shaped, and the quality of this evidence was graded as limited (likelihood of causality: limited‐no conclusion). The evidence on recreational physical activity and lower risk of all‐cause mortality (relative risk [RR] highest vs. lowest: 0.69, 95% confidence interval [CI]: 0.62–0.77) and recurrence/disease‐free survival (RR: 0.80, 95% CI: 0.70–0.92) was graded as limited‐suggestive. There was limited‐suggestive evidence for the associations between healthy dietary and/or lifestyle patterns (including diets that comprised plant‐based foods), intake of whole grains and coffee with lower risk of all‐cause mortality, and between unhealthy dietary patterns and intake of sugary drinks with higher risk of all‐cause mortality. The evidence for other exposures on colorectal cancer outcomes was sparse and graded as limited‐no conclusion. Analyses were conducted excluding cancer patients with metastases without substantial changes in the findings. Well‐designed intervention and cohort studies are needed to support the development of lifestyle recommendations for colorectal cancer patients

Gender and race influence metabolic benefits of fitness in children: a cross-sectional study

<p>Abstract</p> <p>Background</p> <p>Increasing obesity and poor cardiovascular fitness (CVF) contribute to higher rates of type 2 diabetes mellitus (T2DM) in children. While the relative contributions of fitness and body fat on development of insulin resistance (IR) in children and adolescents remains unresolved, gender- and race-specific differences likely exist in the degree to which CVF influences IR and risk for T2DM. Better understanding of how gender and race affect interactions between body fat, CVF, and metabolic health would be helpful in designing effective and targeted strategies to reduce obesity-associated disease risk. We evaluated whether metabolic benefits of fitness on reducing inflammation and insulin resistance (IR) are affected by gender and race.</p> <p>Methods</p> <p>This cross-sectional study included 203 healthy children (mean age 12.2 y, 50% male, 46% non-Hispanic white (NHW), 54% racially diverse (RD)). Fasting insulin, glucose, hsCRP, and adiponectin were measured; race was self-reported; cardiovascular fitness (CVF) was evaluated by the Progressive Aerobic Cardiovascular Endurance Run. Associations between inflammation and gender, race, and CVF were evaluated using analysis of covariance. Multivariate regression analysis identified independent predictors of IR.</p> <p>Results</p> <p>Fitness and inflammation were inversely related in both males and females (p < 0.01); this effect was marginally stronger in RD children (p = 0.06) and non-overweight males (p = 0.07). High BMI (p < 0.001), low fitness (p = 0.006), and (female) gender (p = 0.003) were independently associated with higher HOMA-IR. In males, BMI and fitness, but not race independently predicted HOMA-IR. In females, BMI and race, but not fitness independently predicted HOMA-IR.</p> <p>Conclusions</p> <p>In middle school children, the beneficial effects of fitness vary based on gender and race. High CVF has an enhanced anti-inflammatory effect in male and RD children. While BMI is the strongest predictor of IR in the study group as a whole, fitness is a significant predictor of IR only in males, and race is a significant predictor of IR only in females.</p

Antimicrobial resistance among migrants in Europe: a systematic review and meta-analysis

BACKGROUND: Rates of antimicrobial resistance (AMR) are rising globally and there is concern that increased migration is contributing to the burden of antibiotic resistance in Europe. However, the effect of migration on the burden of AMR in Europe has not yet been comprehensively examined. Therefore, we did a systematic review and meta-analysis to identify and synthesise data for AMR carriage or infection in migrants to Europe to examine differences in patterns of AMR across migrant groups and in different settings. METHODS: For this systematic review and meta-analysis, we searched MEDLINE, Embase, PubMed, and Scopus with no language restrictions from Jan 1, 2000, to Jan 18, 2017, for primary data from observational studies reporting antibacterial resistance in common bacterial pathogens among migrants to 21 European Union-15 and European Economic Area countries. To be eligible for inclusion, studies had to report data on carriage or infection with laboratory-confirmed antibiotic-resistant organisms in migrant populations. We extracted data from eligible studies and assessed quality using piloted, standardised forms. We did not examine drug resistance in tuberculosis and excluded articles solely reporting on this parameter. We also excluded articles in which migrant status was determined by ethnicity, country of birth of participants' parents, or was not defined, and articles in which data were not disaggregated by migrant status. Outcomes were carriage of or infection with antibiotic-resistant organisms. We used random-effects models to calculate the pooled prevalence of each outcome. The study protocol is registered with PROSPERO, number CRD42016043681. FINDINGS: We identified 2274 articles, of which 23 observational studies reporting on antibiotic resistance in 2319 migrants were included. The pooled prevalence of any AMR carriage or AMR infection in migrants was 25·4% (95% CI 19·1-31·8; I2 =98%), including meticillin-resistant Staphylococcus aureus (7·8%, 4·8-10·7; I2 =92%) and antibiotic-resistant Gram-negative bacteria (27·2%, 17·6-36·8; I2 =94%). The pooled prevalence of any AMR carriage or infection was higher in refugees and asylum seekers (33·0%, 18·3-47·6; I2 =98%) than in other migrant groups (6·6%, 1·8-11·3; I2 =92%). The pooled prevalence of antibiotic-resistant organisms was slightly higher in high-migrant community settings (33·1%, 11·1-55·1; I2 =96%) than in migrants in hospitals (24·3%, 16·1-32·6; I2 =98%). We did not find evidence of high rates of transmission of AMR from migrant to host populations. INTERPRETATION: Migrants are exposed to conditions favouring the emergence of drug resistance during transit and in host countries in Europe. Increased antibiotic resistance among refugees and asylum seekers and in high-migrant community settings (such as refugee camps and detention facilities) highlights the need for improved living conditions, access to health care, and initiatives to facilitate detection of and appropriate high-quality treatment for antibiotic-resistant infections during transit and in host countries. Protocols for the prevention and control of infection and for antibiotic surveillance need to be integrated in all aspects of health care, which should be accessible for all migrant groups, and should target determinants of AMR before, during, and after migration. FUNDING: UK National Institute for Health Research Imperial Biomedical Research Centre, Imperial College Healthcare Charity, the Wellcome Trust, and UK National Institute for Health Research Health Protection Research Unit in Healthcare-associated Infections and Antimictobial Resistance at Imperial College London

Effects of antiplatelet therapy on stroke risk by brain imaging features of intracerebral haemorrhage and cerebral small vessel diseases: subgroup analyses of the RESTART randomised, open-label trial

Background Findings from the RESTART trial suggest that starting antiplatelet therapy might reduce the risk of recurrent symptomatic intracerebral haemorrhage compared with avoiding antiplatelet therapy. Brain imaging features of intracerebral haemorrhage and cerebral small vessel diseases (such as cerebral microbleeds) are associated with greater risks of recurrent intracerebral haemorrhage. We did subgroup analyses of the RESTART trial to explore whether these brain imaging features modify the effects of antiplatelet therapy

Polymersome-Mediated Delivery of Combination Anticancer Therapy to Head and Neck Cancer Cells: 2D and 3D in Vitro Evaluation

Polymersomes have the potential to encapsulate and deliver chemotherapeutic drugs into tumor cells, reducing off-target toxicity that often compromises anticancer treatment. Here, we assess the ability of the pH-sensitive poly 2-(methacryloyloxy)ethyl phosphorylcholine (PMPC)- poly 2-(diisopropylamino)ethyl methacrylate (PDPA) polymersomes to encapsulate chemotherapeutic agents for effective combinational anticancer therapy. Polymersome uptake and ability to deliver encapsulated drugs into healthy normal oral cells and oral head and neck squamous cell carcinoma (HNSCC) cells was measured in two and three-dimensional culture systems. PMPC-PDPA polymersomes were more rapidly internalized by HNSCC cells compared to normal oral cells. Polymersome cellular uptake was found to be mediated by class B scavenger receptors. We also observed that these receptors are more highly expressed by cancer cells compared to normal oral cells, enabling polymersome-mediated targeting. Doxorubicin and paclitaxel were encapsulated into pH-sensitive PMPC-PDPA polymersomes with high efficiencies either in isolation or as a dual-load for both singular and combinational delivery. In monolayer culture, only a short exposure to drug-loaded polymersomes was required to elicit a strong cytotoxic effect. When delivered to three-dimensional tumor models, PMPC-PDPA polymersomes were able to penetrate deep into the center of the spheroid resulting in extensive cell damage when loaded with both singular and dual-loaded chemotherapeutics. PMPC-PDPA polymersomes offer a novel system for the effective delivery of chemotherapeutics for the treatment of HNSCC. Moreover, the preferential internalization of PMPC polymersomes by exploiting elevated scavenger receptor expression on cancer cells opens up the opportunity to target polymersomes to tumors