640 research outputs found
Impact of Pooling Samples on Analytic Sensitivity of a Real-Time Reverse Transcriptase PCR Assay for SARS CoV-2
During the COVID-19 pandemic, laboratories experienced periods of shortages for certain critical materials required to meet the high demand for SARS-CoV-2 testing. The U.S. Food & Drug Administration provided a template for molecular diagnostic testing, including guidance for a specimen pooling process in order to evaluate performance of the SARS-CoV-2 nucleic acid amplification assay. This study aimed to evaluate the testing of pooled specimens consisting of four nasopharyngeal swab specimens using the Luminex ARIES® nucleic acid amplification platform. Results indicated that there was a loss of analytic sensitivity with pooled nasopharyngeal swab samples, demonstrating that this approach should be balanced against material shortages and the clinical utility of a less sensitive assay
Urinary ATP and visualization of intracellular bacteria: a superior diagnostic marker for recurrent UTI in renal transplant recipients?
Renal transplant recipients (RTR) are highly susceptible to urinary tract infections (UTIs) with over 50% of patients having at least one UTI within the first year. Yet it is generally acknowledged that there is considerable insensitivity and inaccuracy in routine urinalysis when screening for UTIs. Thus a large number of transplant patients with genuine urine infections may go undiagnosed and develop chronic recalcitrant infections, which can be associated with graft loss and morbidity. Given a recent study demonstrating ATP is released by urothelial cells in response to bacteria exposure, possibly acting at metabotropic P2Y receptors mediating a proinflammatory response, we have investigated alternative, and possibly more appropriate, urinalysis techniques in a cohort of RTRs.Mid-stream urine (MSU) samples were collected from 53 outpatient RTRs. Conventional leukocyte esterase and nitrite dipstick tests, and microscopic pyuria counts (in 1 ?l), ATP concentration measurements, and identification of intracellular bacteria in shed urothelial cells, were performed on fresh unspun samples and compared to ‘gold-standard’ bacterial culture results.Of the 53 RTRs, 22% were deemed to have a UTI by ‘gold-standard’ conventional bacteria culture, whereas 87%, 8% and 4% showed evidence of UTIs according to leukocyte esterase dipstick, nitrite dipstick, and a combination of both dipsticks, respectively. Intracellular bacteria were visualized in shed urothelial cells of 44% of RTRs, however only 1 of the 23 RTRs (44%) was deemed to have a UTI by conventional bacteria culture. A significant association of the ‘gold-standard’ test with urinary ATP concentration combined with visualization of intracellular bacteria in shed urothelial cells was determined using the Fisher’s exact test.It is apparent that standard bedside tests for UTIs give variable results and that seemingly quiescent bacteria in urothelial cells are very common in RTRs and may represent a focus of subclinical infection. Furthermore, our results suggest urinary ATP concentration combined with detection of intracellular bacteria in shed urinary epithelial cells may be a sensitive means by which to detect ‘occult’ infection in RTRs
Abundance- and Activity-Based Proteomics in Platelet Biology
Human platelets are thought to express approximately 2000–3000 proteins, but post-translational modifications, alternatively spliced variants and a rich diversity of vertebrate domain architectures likely make this a conservative estimate. Even though rapidly advancing proteomic techniques have facilitated the identification of roughly one third of the platelet proteome, a combination of abundance-based and activity-based proteomics methodologies is needed for elucidation of platelet functional characteristics including the definition of a “core proteome” and recognition of diverse enzyme activity profiles associated with various physiological states. In this review, we describe the latest mass spectrometry-based techniques capable of providing some of these physiological details required for more comprehensive evaluation of the human platelet repertoire
Saving babies’ lives project impact and results evaluation (SPiRE): a mixed methodology study
Characteristics of alcohol recovery narratives: Systematic review and narrative synthesis
Background and aims Narratives of recovery from alcohol misuse have been analysed in a range of research studies. This paper aims to produce a conceptual framework describing the characteristics of alcohol misuse recovery narratives that are in the research literature, to inform the development of research, policy, and practice. Methods Systematic review was conducted following PRISMA guidelines. Electronic searches of databases (Ovid MEDLINE, EMBASE, CINHAL, PsychInfo, AMED and SCOPUS), grey literature, and citation searches for included studies were conducted. Alcohol recovery narratives were defined as “first-person lived experience accounts, which includes elements of adversity, struggle, strength, success, and survival related to alcohol misuse, and refer to events or actions over a period of time”. Frameworks were synthesised using a three-stage process. Sub-group analyses were conducted on studies presenting analyses of narratives with specific genders, ages, sexualities, ethnicities, and dual diagnosis. The review was prospectively registered (PROSPERO CRD42021235176). Results 32 studies were included (29 qualitative, 3 mixed-methods, 1055 participants, age range 17-82years, 52.6% male, 46.4% female). Most were conducted in the United States (n = 15) and Europe (n = 11). No included studies analysed recovery narratives from lower income countries. Treatment settings included Alcoholic Anonymous (n = 12 studies), other formal treatment, and ‘natural recovery’. Eight principle narrative dimensions were identified (genre, identity, recovery setting, drinking trajectory, drinking behaviours, stages, spirituality and religion, and recovery experience) each with types and subtypes. All dimensions were present in most subgroups. Shame was a prominent theme for female narrators, lack of sense of belonging and spirituality were prominent for LGBTQ+ narrators, and alienation and inequality were prominent for indigenous narrators. Conclusions Review provides characteristics of alcohol recovery narratives, with implications for both research and healthcare practice. It demonstrated knowledge gaps in relation to alcohol recovery narratives of people living in lower income countries, or those who recovered outside of mainstream services
Cluster-randomised controlled trials of individual and combined water, sanitation, hygiene and nutritional interventions in rural Bangladesh and Kenya: the WASH Benefits study design and rationale.
INTRODUCTION: Enteric infections are common during the first years of life in low-income countries and contribute to growth faltering with long-term impairment of health and development. Water quality, sanitation, handwashing and nutritional interventions can independently reduce enteric infections and growth faltering. There is little evidence that directly compares the effects of these individual and combined interventions on diarrhoea and growth when delivered to infants and young children. The objective of the WASH Benefits study is to help fill this knowledge gap. METHODS AND ANALYSIS: WASH Benefits includes two cluster-randomised trials to assess improvements in water quality, sanitation, handwashing and child nutrition-alone and in combination-to rural households with pregnant women in Kenya and Bangladesh. Geographically matched clusters (groups of household compounds in Bangladesh and villages in Kenya) will be randomised to one of six intervention arms or control. Intervention arms include water quality, sanitation, handwashing, nutrition, combined water+sanitation+handwashing (WSH) and WSH+nutrition. The studies will enrol newborn children (N=5760 in Bangladesh and N=8000 in Kenya) and measure outcomes at 12 and 24 months after intervention delivery. Primary outcomes include child length-for-age Z-scores and caregiver-reported diarrhoea. Secondary outcomes include stunting prevalence, markers of environmental enteropathy and child development scores (verbal, motor and personal/social). We will estimate unadjusted and adjusted intention-to-treat effects using semiparametric estimators and permutation tests. ETHICS AND DISSEMINATION: Study protocols have been reviewed and approved by human subjects review boards at the University of California, Berkeley, Stanford University, the International Centre for Diarrheal Disease Research, Bangladesh, the Kenya Medical Research Institute, and Innovations for Poverty Action. Independent data safety monitoring boards in each country oversee the trials. This study is funded by a grant from the Bill & Melinda Gates Foundation to the University of California, Berkeley. REGISTRATION: Trial registration identifiers (http://www.clinicaltrials.gov): NCT01590095 (Bangladesh), NCT01704105 (Kenya)
The U.S. Inland Creel and Angler Survey Catalog (CreelCat): Development, Applications, and Opportunities
Inland recreational fishing, defined as primarily leisure-driven fishing in freshwaters, is a popular pastime in the USA. State natural resource agencies endeavor to provide high-quality and sustainable fishing opportunities for anglers. Managers often use creel and other angler survey data to inform state- and waterbody-level management efforts. Despite the broad implementation of angler surveys and their importance to fisheries management at state scales, regional and national coordination among these activities is minimal, limiting data applicability for larger-scale management practices and research. Here, we introduce the U.S. Inland Creel and Angler Survey Catalog (CreelCat), a first-of-its-kind, publicly available national database of angler survey data that establishes a baseline of national inland recreational fishing metrics. We highlight research and management applications to help support sustainable inland recreational fishing practices, consider cautions, and make recommendations for implementation
Mass Transport in Surface Diffusion of van der Waals Bonded Systems: Boosted by Rotations?
Mass transport at a surface is a key factor in heterogeneous catalysis. The rate is determined by excitation across a translational barrier and depends on the energy landscape and the coupling to the thermal bath of the surface. Here we use helium spin-echo spectroscopy to track the microscopic motion of benzene adsorbed on Cu(001) at low coverage (θ ∼ 0.07 ML). Specifically, our combined experimental and computational data determine both the absolute rate and mechanism of the molecular motion. The observed rate is significantly higher by a factor of 3.0 ± 0.1 than is possible in a conventional, point-particle model and can be understood only by including additional molecular (rotational) coordinates. We argue that the effect can be described as an entropic contribution that enhances the population of molecules in the transition state. The process is generally relevant to molecular systems and illustrates the importance of the pre-exponential factor alongside the activation barrier in studies of surface kinetics.The authors are grateful for the support of the Leverhulme Trust (HH) and the Royal Society (MS). Via our membership of the UK’s HEC Materials Chemistry Consortium, which is funded by EPSRC (EP/L000202), this work used the ARCHER UK National Supercomputing Service
Association of Accelerometry-Measured Physical Activity and Cardiovascular Events in Mobility-Limited Older Adults: The LIFE (Lifestyle Interventions and Independence for Elders) Study.
BACKGROUND:Data are sparse regarding the value of physical activity (PA) surveillance among older adults-particularly among those with mobility limitations. The objective of this study was to examine longitudinal associations between objectively measured daily PA and the incidence of cardiovascular events among older adults in the LIFE (Lifestyle Interventions and Independence for Elders) study. METHODS AND RESULTS:Cardiovascular events were adjudicated based on medical records review, and cardiovascular risk factors were controlled for in the analysis. Home-based activity data were collected by hip-worn accelerometers at baseline and at 6, 12, and 24 months postrandomization to either a physical activity or health education intervention. LIFE study participants (n=1590; age 78.9±5.2 [SD] years; 67.2% women) at baseline had an 11% lower incidence of experiencing a subsequent cardiovascular event per 500 steps taken per day based on activity data (hazard ratio, 0.89; 95% confidence interval, 0.84-0.96; P=0.001). At baseline, every 30 minutes spent performing activities ≥500 counts per minute (hazard ratio, 0.75; confidence interval, 0.65-0.89 [P=0.001]) were also associated with a lower incidence of cardiovascular events. Throughout follow-up (6, 12, and 24 months), both the number of steps per day (per 500 steps; hazard ratio, 0.90, confidence interval, 0.85-0.96 [P=0.001]) and duration of activity ≥500 counts per minute (per 30 minutes; hazard ratio, 0.76; confidence interval, 0.63-0.90 [P=0.002]) were significantly associated with lower cardiovascular event rates. CONCLUSIONS:Objective measurements of physical activity via accelerometry were associated with cardiovascular events among older adults with limited mobility (summary score >10 on the Short Physical Performance Battery) both using baseline and longitudinal data. CLINICAL TRIAL REGISTRATION:URL: http://www.clinicaltrials.gov. Unique identifier: NCT01072500
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