From guide to guard-activation mechanism of the stress-sensing chaperone Get3.

Oxidative stress conditions can cause ATP depletion, oxidative protein unfolding, and potentially toxic protein aggregation. To alleviate this proteotoxic stress, the highly conserved yeast protein, Get3, switches from its guiding function as an ATP-dependent targeting factor for tail-anchored proteins to its guarding function as an ATP-independent molecular chaperone that prevents irreversible protein aggregation. Here, we demonstrate that activation of Get3's chaperone function follows a tightly orchestrated multi-step process, centered around the redox status of two conserved cysteines, whose reactivity is directly controlled by Get3's nucleotide-binding state. Thiol oxidation causes local unfolding and the transition into chaperone-active oligomers. Vice versa, inactivation requires the reduction of Get3's cysteines followed by ATP-binding, which allows the transfer of bound client proteins to ATP-dependent chaperone systems for their effective refolding. Manipulating this fine-tuned cycle of activation and inactivation in yeast impairs oxidative stress resistance and growth, illustrating the necessity to tightly control Get3's intrinsic chaperone function.

Continuity of Care Advocate Model (CCAM): Healthcare Workers' Perspectives on Quality Stroke Care at an Acute Unit, Rehabilitation Center and Community Rehabilitation Program in Singapore.

Physicians, nurses, social workers, and allied health professionals including physiotherapists and occupational therapists play important roles as they work closely with stroke survivors to improve functional independence in daily activities and quality of life. Yet, in Singapore little is known about their perspectives on what constitute quality stroke care based on their clinical experiences. In this project, our qualitative interviews with 15 healthcare workers at a major stroke center in the country yielded a Continuity of Care Advocate Model (CCAM) to help us better understand our participants' experience-based perspectives on quality stroke care. We found that CCAM, constructed based on the perspectives of HCWs across a stroke care continuum, is a holistic model of quality stroke care which prioritizes support for patients and their families throughout the patient's health trajectory. We conclude by discussing how this model is aligned with and differs from current research on definitions of care continuity.

Association between increased-risk donor social behaviors and recipient outcomes after heart transplantation.

BACKGROUND: This study aims to investigate the association between social behaviors of increased-risk donors (IRD) and recipient outcomes after heart transplantation. METHODS: The United Network for Organ Sharing (UNOS) database was queried to identify patients who received a heart transplant between 2004 and 2015. Patients were grouped based on donor's risk status (IRD vs standard risk donor [SRD]). Recipients of IRD were categorized based on donor social behaviors (SB), and recipient survival was assessed. Cox regression analysis was used to identify associations between SB of donors and recipient survival. RESULTS: Out of 22 333 heart transplantations performed during the study period, 2769 (12%) received an IRD graft with the following SB: Unprofessional tattoos or piercings (n = 1722) (63%), cocaine use (n = 916) (33%), heavy smoking (n = 437) (16%), and heavy alcohol abuse (n = 610) (22%). Viral screens detected 72(3%) hepatitis B virus (HBV) positive and 12 (0.4%) hepatitis C virus (HCV) positive at donation. There was no difference in recipient survival based on both donor risk and their social behaviors. Cox regression analysis found only donor HCV infection and non-identical ABO mismatch to be associated with poor recipient survival among recipients of IR grafts. CONCLUSION: Cardiac allografts from IRD, serologically negative for viruses, can safely be used. There is no association between social behaviors of IRD and recipient survival.

Treatment preferences of patients with relapsed and refractory multiple myeloma: a qualitative study.

BACKGROUND: Multiple myeloma is a haematological malignancy characterized by significant morbidity and mortality. This study sought to develop an in-depth understanding of patients' lived experiences of relapsed or refractory multiple myeloma (RRMM) and its treatment, and to identify which features of treatment were most important to them. METHODS: Qualitative interviews and focus groups (FGs) were conducted with 32 people living with RRMM across Canada. In Phase 1, interviews focused on participants' accounts of their experiences with the disease and its treatment and laid the groundwork for the FGs (Phase 2). The FGs developed a deeper understanding of patients' treatment priorities. Interview and FG transcripts were coded for emergent themes and patterns. RESULTS: The interviews identified important side effects that had significant impacts on patients' lives, including physical, cognitive, and psychological/emotional side effects. Participants also identified specific treatment features (attributes) that were important to them. These were compiled into a list and used in the FGs to understand patients' priorities. Higher prioritized attributes were: life expectancy, physical and cognitive side effects, and financial impact. Mode of administration, treatment intervals, psychological side effects, and sleep/mood effects were identified as lower priorities. CONCLUSIONS: RRMM and its treatments impact importantly on patients' quality-of-life across a range of domains. Patients prioritized treatment features that could enhance life expectancy, minimize side effects and offset financial burdens. IMPLICATIONS FOR CANCER SURVIVORS: A clear articulation of patient priorities can contribute to efforts to design treatment with patients' concerns in mind, thereby promoting a more patient-centered approach to care.

Radiation-Tolerant Bacteria Isolated from High Altitude Soil in Tibet.

This study reports the identification of ionising radiation tolerant bacteria from a high elevation arid region of central Tibet. Nineteen isolates were isolated from soil exposed to ionising radiation at doses from 0 to 15 kGy. Isolates were phylogenetically characterised using 16S rRNA gene sequences. Most isolates comprised taxa from the Actinobacteria, Cyanobacteria, Firmicutes and proteobacteria and these survived doses up to 5 kGy. The Firmicutes and Deinococci also survived doses up to 10 kGy, and the highest dose of 15 kGy was survived only by the Deinococci. No altitude-related pattern was discernible within the range 4638-5240 m, instead culturable bacterial estimates for irradiated soil were strongly influenced by the abundance of Deinococci. We conclude that the relatively high UV exposure in Tibet has contributed to the high diversity of radiation tolerant soil bacteria. In addition, the strong association between desiccation-tolerance and radiation tolerance pathways suggests the arid environment may also have selected in favour of radiation tolerant taxa.

Phylogenetic diversity of a microbialite reef in a cold alkaline freshwater lake.

A culture-independent multidomain survey of biodiversity in microbialite structures within the cold alkaline Pavilion Lake (British Columbia, Canada) revealed a largely homogenous community at depths from 10 to 30 m. Real-time quantitative PCR was used to demonstrate that bacteria comprised approximately 80%-95% of recoverable phylotypes. Archaeal phylotypes accounted for <5% of the community in microbialites exposed to the water column, while structures in sediment contact supported 4- to 5-fold higher archaeal abundance. Eukaryal phylotypes were rare and indicated common aquatic diatoms that were concluded not to be part of the microbialite community. Phylogenetic analysis of rRNA genes from clone libraries (N = 491) revealed that alphaproteobacterial phylotypes were most abundant. Cyanobacterial phylotypes were highly diverse but resolved into 4 dominant genera: Acaryochloris, Leptolyngbya, Microcoleus, and Pseudanabaena. Interestingly, microbialite cyanobacteria generally affiliated phylogenetically with aquatic and coral cyanobacterial groups rather than those from stromatolites. Other commonly encountered bacterial phylotypes were from members of the Acidobacteria, with relatively low abundance of the Betaproteobacteria, Chloroflexi, Nitrospirae, and Planctomycetes. Archaeal diversity (N = 53) was largely accounted for by Euryarchaeota, with most phylotypes affiliated with freshwater methanogenic taxa.

Why prescribe antibiotics? A systematic review of knowledge, tension, and motivation among clinicians in low-, middle- and high-income countries.

Medical professionals such as physicians and veterinarians are responsible for appropriate antimicrobial prescription (AMP) and use. Although seemingly straightforward, the factors influencing antibiotic prescription, a category of antimicrobials, are complex. Many studies have been conducted in the past two decades on this subject. As a result, there is a plethora of empirical evidence regarding the factors influencing clinicians' AMP practices. AIM: A systematic review of AMR studies on AMP was conducted, condensing findings according to a combination of the Knowledge, Attitude, and Practice (KAP) and Capacity, Opportunity, Motivation-Behavior (COM-B) models. Review findings were then synthesized and analyzed for policy implementation according to the Consolidated Framework for Implementation Research (CFIR). DESIGN AND METHODOLOGY: A systematic literature review was conducted according to PRISMA guidelines to identify peer-reviewed papers indexed in pre-determined medical science, social sciences, and humanities databases that apply the KAP model in their investigations. Antimicrobial prescription factors were compared and contrasted among low- and middle-income countries (LMICs) and high-income countries (HICs). FINDINGS: The KAP model is a heuristic and structured framework for identifying and classifying respondents' knowledge. However, other than medical knowledge, factors that influence prescription decision-making can be expanded to include attitudes, perception, personal affinities, professional circumstances, relational pressure, and social norms.

Prescribing antibiotics prudently-A survey of policy implementation drivers among physicians and veterinarians.

Background: As the antimicrobial resistance (AMR) problem accelerates, humans and animals are suffering from the consequences of infections with diminishing antimicrobial treatment options. Within the One Medicine and One Health mandate, which denotes a collaborative, multisectoral, and transdisciplinary approach to improve medicine and health across human and animal sectors, we investigate how human and veterinary medical practitioners apply their medical and policy knowledge in prescribing antimicrobials. Different regions and locations establish different intermediary policies and programs to support clinicians in that pursuit. In Hong Kong, there are locally adapted programs at governance and clinical levels in the human medical field. However, there is no locally adapted veterinary antibiotic prescription guideline or stewardship program, and veterinarians adopt overseas or international professions' antimicrobial use guidelines. Such a policy environment creates a natural experiment to compare local policy implementation conditions and clinicians' knowledge, perception, and practice. Method: We construct the investigative survey tool by adaptation of Knowledge, Attitude, and Practice (KAP) and Capacity, Opportunity, and Motivation-Behavior (COM-B) models. We identify, compare and contrast factors that influence clinicians' antimicrobial prescription behavior. The factors are considered both intrinsically, such as personal attributes, and extrinsically, such as societal and professional norms. Findings: The absence of locally adopted antimicrobial guidelines influences AMR stewardship program implementation in local Hong Kong veterinary community. As medical allies, physicians and veterinarians share similar demographic influence, organization considerations and perception of public awareness. Both cohorts prescribe more prudently with more years-in-practice, time available to communicate with patients or caretakers, and public awareness and support.

The chemokine CCL5 regulates glucose uptake and AMP kinase signaling in activated T cells to facilitate chemotaxis.

Recruitment of effector T cells to sites of infection or inflammation is essential for an effective adaptive immune response. The chemokine CCL5 (RANTES) activates its cognate receptor, CCR5, to initiate cellular functions, including chemotaxis. In earlier studies, we reported that CCL5-induced CCR5 signaling activates the mTOR/4E-BP1 pathway to directly modulate mRNA translation. Specifically, CCL5-mediated mTOR activation contributes to T cell chemotaxis by initiating the synthesis of chemotaxis-related proteins. Up-regulation of chemotaxis-related proteins may prime T cells for efficient migration. It is now clear that mTOR is also a central regulator of nutrient sensing and glycolysis. Herein we describe a role for CCL5-mediated glucose uptake and ATP accumulation to meet the energy demands of chemotaxis in activated T cells. We provide evidence that CCL5 is able to induce glucose uptake in an mTOR-dependent manner. CCL5 treatment of ex vivo activated human CD3(+) T cells also induced the activation of the nutrient-sensing kinase AMPK and downstream substrates ACC-1, PFKFB-2, and GSK-3ß. Using 2-deoxy-d-glucose, an inhibitor of glucose uptake, and compound C, an inhibitor of AMPK, experimental data are presented that demonstrate that CCL5-mediated T cell chemotaxis is dependent on glucose, as these inhibitors inhibit CCL5-mediated chemotaxis in a dose-dependent manner. Altogether, these findings suggest that both glycolysis and AMPK signaling are required for efficient T cell migration in response to CCL5. These studies extend the role of CCL5 mediated CCR5 signaling beyond lymphocyte chemotaxis and demonstrate a role for chemokines in promoting glucose uptake and ATP production to match energy demands of migration.

One Health Surveillance of Antimicrobial Use and Resistance: Challenges and Successes of Implementing Surveillance Programs in Sri Lanka.

BACKGROUND: Sri Lanka is a low-income country, as defined by the World Bank. The country suffered further economic downturn during the COVID-19 pandemic. This situation adversely affected the prioritization of policies and programs around healthcare and public health. In particular, inflation, fuel prices, and shortage of food supplies increased struggles to implement antimicrobial resistance (AMR) programs. However, in the long run, it is crucial to gather data and evidence to plan AMR policies and track interventions. (1) Aim: To establish and reiterate the importance of prioritizing AMR programs in the One Health framework, the Fleming Fellows collected and studied antimicrobial use/consumption (AMU/AMC) and resistance (AMR) in humans, food-producing animals, and the environment. (2) Methods: A systematic and cross-sectional study was conducted between 2019 and 2021. By way of coordinating an AMU/AMC and AMR prevalence study across six agencies from human health and food-producing animal sectors, the authors established a field epidemiology study, laboratory testing, and data processing at their institutions. AMU/AMC patterns were surveyed using questionnaires and interviews, while AMR samples were collected for antibiotic susceptibility tests and genomic tests. Samples were tested for phenotypic and genotypic resistance. (3) Results: In human samples, resistance was highest to beta-lactam antibiotics. In non-human samples, resistance was highest to erythromycin, a highest-priority, critically important antibiotic defined by the World Health Organization. From government records, tylosin was sold the most in the food-producing animal sector. (4) Conclusions: Sri Lanka AMU and AMR trends in human and non-human sectors can be ascertained by a One Health framework. Further coordinated, consistent, and sustainable planning is feasible, and can help implement an AMU/AMR surveillance system in Sri Lanka.

Experiences with COVID-19 case investigation and contact tracing: A qualitative analysis.

Case investigation and contact tracing (CI/CT) is a critical part of the public health response to COVID-19. Individuals' experiences with CI/CT for COVID-19 varied based on geographic location, changes in knowledge and guidelines, access to testing and vaccination, as well as demographic characteristics including age, race, ethnicity, income, and political ideology. In this paper, we explore the experiences and behaviors of adults with positive SARS-CoV-2 test results, or who were exposed to a person with COVID-19, to understand their knowledge, motivations, and facilitators and barriers to their actions. We conducted focus groups and one-on-one interviews with 94 cases and 90 contacts from across the United States. We found that participants were concerned about infecting or exposing others, which motivated them to isolate or quarantine, notify contacts, and get tested. Although most cases and contacts were not contacted by CI/CT professionals, those who were reported a positive experience and received helpful information. Many cases and contacts reported seeking information from family, friends, health care providers, as well as television news and Internet sources. Although participants reported similar perspectives and experiences across demographic characteristics, some highlighted inequities in receiving COVID-19 information and resources.

Subsidized veterinary extension services may reduce antimicrobial resistance in aquaculture.

Antibiotic use in aquaculture has become very controversial vis-à-vis driving antimicrobial resistance (AMR) in aquatic bacterial populations. The AMR trends in fish pathogens in Hong Kong over a four-year period suggests that providing small stakeholder farmers with free veterinary advice on fish health issues and treatments, as well as subsidized quality-assured medicines, likely reduced AMR. We observed a dramatic reduction in the proportion of bacteria resistant to oxolinic acid, oxytetracycline, and florfenicol on local aquaculture farms between 2018 and 2021. These decreases coincided with either a change in antibiotic use practices on farms (i.e. with oxytetracycline), or the reduction in the use of specific drugs (i.e. oxolinic acid and florfenicol). We did not observe a similar decline in the resistance pattern to commonly used antibiotics in human medicine in the same fish bacteria. Resistance to these products, which were unlikely to be used by the farmers in our study, was very high. Our finding suggests that both human and veterinary use of antibiotics in Hong Kong may have an influence on the AMR of bacteria in the aquatic environment.

Longitudinal monitoring reveals the emergence and spread of blaGES-5-harboring carbapenem-resistant Klebsiella quasipneumoniae in a Hong Kong hospital wastewater discharge line.

Testing hospital wastewater (HWW) is potentially an effective, long-term approach for monitoring trends in antimicrobial resistance (AMR) patterns in health care institutions. Over a year, we collected wastewater samples from the clinical and non-clinical sites of a tertiary hospital and from a downstream wastewater treatment plant (WWTP). We focused on the extent of carbapenem resistance among Enterobacteriaceae isolates given their clinical importance. Escherichia coli and Klebsiella spp. were the most frequently isolated Enterobacteriaceae species at all sampling sites. Additionally, a small number of isolates belonging to ESKAPE pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species), except K. pneumoniae, were detected. Of the 232 Klebsiella spp. isolates, 100 (43.1 %) were multi-drug resistant (MDR), with 46 being carbapenem-resistant. Most of these carbapenem-resistant isolates were K. quasipneumoniae (CRKQ) (n = 44). All CRKQ isolates were isolated from the wastewater of a clinical site that includes intensive care units, which also yielded significantly more multi-drug resistant isolates compared to all other sampling sites. Among the CRKQ isolates, blaGES-5 genes (n = 42) were the primary genetic determinant of carbapenem resistance. Notably, three different CRKQ isolates, collected within the same month in HWW and the influent and effluent flow of the WWTP, shared >99 % sequence similarity between their blaGES-5 genes and between their flanking regions and upstream integron-integrase region. The influent isolate was phylogenetically close to K. quasipnuemoniae isolates from wastewater collected in Japan. Its blaGES-5 gene and surrounding sequences were > 99 % identical to blaGES-24 genes found in the Japanese isolates. Our results suggest that testing samples from sites located closer to hospitals could support antibiotic stewardship programs compared to samples collected further downstream. Moreover, testing samples collected regularly from WWTPs may reflect the local and global spread of pathogens and their resistances.

Exposure to HIV-1 directly impairs mucosal epithelial barrier integrity allowing microbial translocation.

While several clinical studies have shown that HIV-1 infection is associated with increased permeability of the intestinal tract, there is very little understanding of the mechanisms underlying HIV-induced impairment of mucosal barriers. Here we demonstrate that exposure to HIV-1 can directly breach the integrity of mucosal epithelial barrier, allowing translocation of virus and bacteria. Purified primary epithelial cells (EC) isolated from female genital tract and T84 intestinal cell line were grown to form polarized, confluent monolayers and exposed to HIV-1. HIV-1 X4 and R5 tropic laboratory strains and clinical isolates were seen to reduce transepithelial resistance (TER), a measure of monolayer integrity, by 30-60% following exposure for 24 hours, without affecting viability of cells. The decrease in TER correlated with disruption of tight junction proteins (claudin 1, 2, 4, occludin and ZO-1) and increased permeability. Treatment of ECs with HIV envelope protein gp120, but not HIV tat, also resulted in impairment of barrier function. Neutralization of gp120 significantly abrogated the effect of HIV. No changes to the barrier function were observed when ECs were exposed to Env defective mutant of HIV. Significant upregulation of inflammatory cytokines, including TNF-alpha, were seen in both intestinal and genital epithelial cells following exposure to HIV-1. Neutralization of TNF-alpha reversed the reduction in TERs. The disruption in barrier functions was associated with viral and bacterial translocation across the epithelial monolayers. Collectively, our data shows that mucosal epithelial cells respond directly to envelope glycoprotein of HIV-1 by upregulating inflammatory cytokines that lead to impairment of barrier functions. The increased permeability could be responsible for small but significant crossing of mucosal epithelium by virus and bacteria present in the lumen of mucosa. This mechanism could be particularly relevant to mucosal transmission of HIV-1 as well as immune activation seen in HIV-1 infected individuals.

Understanding the Implementation of Antimicrobial Policies: Lessons from the Hong Kong Strategy and Action Plan.

In 2017, the Hong Kong Strategy and Action Plan on Antimicrobial Resistance 2017-2022 (HKSAP) was announced with the aim of tackling the growing threat of antimicrobial resistance (AMR) in Hong Kong. However, little is known about how the planned activities have been implemented. In this study, we examine the status of implementation of the HKSAP using the Smith Policy Implementation Process Model. Semi-structured interviews with 17 informants found that important achievements have been made, including launching educational and training activities targeting the public, farmers, and healthcare professionals; upgrading the AMR surveillance system; and strengthening AMR stewardship and infection control. Nevertheless, participants also identified barriers to greater implementation, such as tensions across sectors, ongoing inappropriate drug use and prescription habits, insufficient human and technical resources, as well as a weak accountability framework. Environmental factors such as the COVID-19 pandemic also affected the implementation of HKSAP. Our study indicated that expanding engagement with the public and professionals, creating a collaborative environment for policy implementation, and building a well-functioning monitoring and evaluation system should be areas to focus on in future AMR policies.

A Universal LC-MS/MS Method for Simultaneous Detection of Antibiotic Residues in Animal and Environmental Samples.

Detecting and monitoring the usage of antibiotics is a critical aspect of efforts to combat antimicrobial resistance. Antibiotic residue testing with existing LC-MS/MS methods is limited in detection range. Current methods also lack the capacity to detect multiple antibiotic residues in different samples simultaneously. In this study, we demonstrate a methodology that permits simultaneous extraction and detection of antibiotic residues in animal and environmental samples. A total of 30 different antibiotics from 13 classes could be qualitatively detected with our methodology. Further study to reduce analytes' matrix effect would allow for quantification of antibiotic residues.

Unpacking multi-level governance of antimicrobial resistance policies: the case of Guangdong, China.

Against the backdrop of universal healthcare coverage and pre-existing policies on antimicrobial use, China has adopted a state-governed, multi-level, top-down policy governance approach around an antimicrobial resistance (AMR) national action plan (NAP). The Plan relies on tightening control over antimicrobial prescription and use in human and animal sectors. At the same time, medical doctors and veterinarians operate in an environment of high rates of infectious diseases, multi-drug resistance and poor livestock husbandry. In exploring the way that policy responsibilities are distributed, this study aims to describe how Guangdong as a province adopts national AMR policies in a tightly controlled public policy system and an economy with high disparity. We draw on an analysis of 225 AMR-relevant Chinese policy documents at the national and sub-national levels. We adopt a multi-level governance perspective and apply a temporal sequence framework to identify and analyse documents. To identify policy detail, we conducted keyword analysis using the Consolidated Framework for Implementation Research (CFIR) on policies that conserve antimicrobials. We also identify pre-existing medical and public policies associated with AMR. Our findings highlight the emphasis and policies around antimicrobial use regulation to address AMR in China.

Ventilatory neural drive in chronically hypercapnic patients with COPD: effects of sleep and nocturnal noninvasive ventilation.

Sleep brings major challenges for the control of ventilation in humans, particularly the regulation of arterial carbon dioxide pressure (P aCO2 ). In patients with COPD, chronic hypercapnia is associated with increased mortality. Therefore, nocturnal high-level noninvasive positive-pressure ventilation (NIV) is recommended with the intention to reduce P aCO2 down to normocapnia. However, the long-term physiological consequences of P aCO2 "correction" on the mechanics of breathing, gas exchange efficiency and resulting symptoms (i.e. dyspnoea) remain poorly understood. Investigating the influence of sleep on the neural drive to breathe and its translation to the mechanical act of breathing is of foremost relevance to create a solid rationale for the use of nocturnal NIV. In this review, we critically discuss the mechanisms by which sleep influences ventilatory neural drive and mechanical consequences in healthy subjects and hypercapnic patients with advanced COPD. We then discuss the available literature on the effects of nocturnal NIV on ventilatory neural drive and respiratory mechanics, highlighting open avenues for further investigation.

Antimicrobial Resistance Policy Protagonists and Processes-A Qualitative Study of Policy Advocacy and Implementation.

Antimicrobial resistance (AMR) fundamentally weakens societal foundations economically and in health care. The development of well-considered policies against AMR is important. However, in many places, AMR policy implementation remains elusive. This study aims to identify enablers and deterrents as well as processes and conditions in AMR policy advocacy. It also aims to identify AMR implementation conditions where AMR national policies are adopted and, to a certain extent, formulated and implemented. This study adopts qualitative research methodology and applies the Grounded Theory Framework to identify thematic findings from interviews conducted in China, Japan, Norway, the United Kingdom (UK), and the United States of America (US). It was identified that AMR policy protagonists are critical to filtering AMR issues and identifying policies "fit to prioritize" and "fit to implement". They have helped move policy prioritization needles in the UK and the US and engaged in diplomatic efforts in the UK. In these cases, no clientelism was considered. In the US, protagonists who talked to the right decision-makers in the right office at the right time both moved AMR issues from individuals to institutional agenda and from social norms to policy agenda. To conclude, there are three thematic policy conditions that are significant to AMR policy advocacy and implementation: committed personal championship, institutionalization of policies, and social norms facilitate AMR policy advocacy and implementation.