217 research outputs found
An analysis of the COVID-19 laboratory dataset at AiBST Laboratory in Harare, Zimbabwe, 2020
Introduction: coronavirus disease 2019 (COVID-19) has become a major public health problem and has spread rapidly around the globe since its first identification in Wuhan, China, in December 2019. Zimbabwe reported its first case on the 20th March 2020, and since then the disease has spread to almost every part of the country. Laboratory testing is important in controlling this pandemic. However, few studies have focused on assessing trends of SARS-CoV-2 laboratory data. We described SARS-CoV-2 data from African Institute of Biomedical Science and Technology (AiBST) Laboratory in Harare, Zimbabwe.
Methods: a retrospective record review of secondary SARS-CoV-2 data from AiBST Laboratory in Harare between May to September 2020 was done. Epi Info TM 7.2.2.6 was used to generate frequencies, proportions and conduct bivariate analysis.
Results: a total of 6,535 SARS-CoV-2 laboratory records were analysed. The median age of the patients was 36 years and 55% (3594/6535) were males. There was an increase in average analytical turn-around time (TAT) of SARS-CoV-2 results from May to August 2020. Analytical and preanalytical TAT remained above 2 days from August to September. Males were 1.18 times at risk of being SARS-CoV-2 infected than females (p<0.05). The risk of being SARS-CoV-2 infected increased with age from 1.06 in the 11-20 age group to 1.45 in the 41-50 age group.
Conclusion: COVID-19 poses a greater threat to the older age groups and to men. The delayed TAT of SARS-CoV-2 results limits the efforts to control the pandemic. Decentralization of testing to provincial and district level would help improve result TAT
Using the gut microbiota as a novel tool for examining colobine primate GI health
Primates of the Colobinae subfamily are highly folivorous. They possess a sacculated foregut and are believed to rely on a specialized gut microbiota to extract sufficient energy from their hard-to-digest diet. Although many colobines are endangered and would benefit from captive breeding programs, maintaining healthy captive populations of colobines can be difficult since they commonly suffer from morbidity and mortality due to gastrointestinal (GI) distress of unknown cause. While there is speculation that this GI distress may be associated with a dysbiosis of the gut microbiota, no study has directly examined the role of the gut microbiota in colobine GI health. In this study, we used high-throughput sequencing to examine the gut microbiota of three genera of colobines housed at the San Diego Zoo: doucs (Pygathrix) (N=7), colobus monkeys (Colobus) (N=4), and langurs (Trachypithecus) (N=5). Our data indicated that GI-healthy doucs, langurs, and colobus monkeys possess a distinct gut microbiota. In addition, GI-unhealthy doucs exhibited a different gut microbiota compared to GI-healthy individuals, including reduced relative abundances of anti-inflammatory Akkermansia. Finally, by comparing samples from wild and captive Asian colobines, we found that captive colobines generally exhibited higher relative abundances of potential pathogens such as Desulfovibrio and Methanobrevibacter compared to wild colobines, implying an increased risk of gut microbial dysbiosis. Together, these results suggest an association between the gut microbiota and GI illness of unknown cause in doucs. Further studies are necessary to corroborate these findings and determine cause-and-effect relationships. Additionally, we found minimal variation in the diversity and composition of the gut microbiota along the colobine GI tract, suggesting that fecal samples may be sufficient for describing the colobine gut microbiota. If these findings can be validated in wild individuals, it will facilitate the rapid expansion of colobine gut microbiome research
Estimating the prevalence of food risk increasing behaviours in UK kitchens
© 2017 Jones et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Foodborne disease poses a serious threat to public health. In the UK, half a million cases are linked to known pathogens and more than half of all outbreaks are associated with catering establishments. The UK Food Standards Agency (FSA) has initiated the UK Food Hygiene Rating Scheme in which commercial food establishments are inspected and scored with the results made public. In this study we investigate the prevalence of food risk increasing behaviours among chefs, catering students and the public. Given the incentive for respondents to misreport when asked about illegal or illicit behaviours we employed a Randomised Response Technique designed to elicit more accurate prevalence rates of such behaviours. We found 14% of the public not always hand-washing immediately after handling raw meat, poultry or fish; 32% of chefs and catering students had worked within 48 hours of suffering from diarrhoea or vomiting. 22% of the public admitted having served meat “on the turn” and 33% of chefs and catering students admitted working in kitchens where such meat was served; 12% of the public and 16% of chefs and catering students admitted having served chicken at a barbeque when not totally sure it was fully cooked. Chefs in fine-dining establishment were less likely to wash their hands after handling meat and fish and those who worked in award winning restaurants were more likely to have returned to work within 48 hours of suffering from diarrhoea and vomiting. We found no correlation between the price of a meal in an establishment, nor its Food Hygiene Rating Score, and the likelihood of any of the food malpractices occurring
Evolutionary aspects of self- and world consciousness in vertebrates
Although most aspects of world and self-consciousness are inherently subjective, neuroscience studies in humans and non-human animals provide correlational and causative indices of specific links between brain activity and representation of the self and the world. In this article we review neuroanatomic, neurophysiological and neuropsychological data supporting the hypothesis that different levels of self and world representation in vertebrates rely upon (i) a \u201cbasal\u201d subcortical system that includes brainstem, hypothalamus and central thalamic nuclei and that may underpin the primary (or anoetic) consciousness likely present in all vertebrates; and (ii) a forebrain system that include the medial and lateral structures of the cerebral hemispheres and may sustain the most sophisticated forms of consciousness [e.g., noetic (knowledge based) and autonoetic, reflective knowledge]. We posit a mutual, bidirectional functional influence between these two major brain circuits. We conclude that basic aspects of consciousness like primary self and core self (based on anoetic and noetic consciousness) are present in many species of vertebrates and that, even self-consciousness (autonoetic consciousness) does not seem to be a prerogative of humans and of some non-human primates but may, to a certain extent, be present in some other mammals and bird
Molecular Evolution of Ultraspiracle Protein (USP/RXR) in Insects
Ultraspiracle protein/retinoid X receptor (USP/RXR) is a nuclear receptor and transcription factor which is an essential component of a heterodimeric receptor complex with the ecdysone receptor (EcR). In insects this complex binds ecdysteroids and plays an important role in the regulation of growth, development, metamorphosis and reproduction. In some holometabolous insects, including Lepidoptera and Diptera, USP/RXR is thought to have experienced several important shifts in function. These include the acquisition of novel ligand-binding properties and an expanded dimerization interface with EcR. In light of these recent hypotheses, we implemented codon-based likelihood methods to investigate if the proposed shifts in function are reflected in changes in site-specific evolutionary rates across functional and structural motifs in insect USP/RXR sequences, and if there is any evidence for positive selection at functionally important sites. Our results reveal evidence of positive selection acting on sites within the loop connecting helices H1 and H3, the ligand-binding pocket, and the dimer interface in the holometabolous lineage leading to the Lepidoptera/Diptera/Trichoptera. Similar analyses conducted using EcR sequences did not indicate positive selection. However, analyses allowing for variation across sites demonstrated elevated non-synonymous/synonymous rate ratios (dN/dS), suggesting relaxed constraint, within the dimerization interface of both USP/RXR and EcR as well as within the coactivator binding groove and helix H12 of USP/RXR. Since the above methods are based on the assumption that dS is constant among sites, we also used more recent models which relax this assumption and obtained results consistent with traditional random-sites models. Overall our findings support the evolution of novel function in USP/RXR of more derived holometabolous insects, and are consistent with shifts in structure and function which may have increased USP/RXR reliance on EcR for cofactor recruitment. Moreover, these findings raise important questions regarding hypotheses which suggest the independent activation of USP/RXR by its own ligand
A communal catalogue reveals Earth’s multiscale microbial diversity
Our growing awareness of the microbial world’s importance and diversity contrasts starkly with our limited understanding of its fundamental structure. Despite recent advances in DNA sequencing, a lack of standardized protocols and common analytical frameworks impedes comparisons among studies, hindering the development of global inferences about microbial life on Earth. Here we present a meta-analysis of microbial community samples collected by hundreds of researchers for the Earth Microbiome Project. Coordinated protocols and new analytical methods, particularly the use of exact sequences instead of clustered operational taxonomic units, enable bacterial and archaeal ribosomal RNA gene sequences to be followed across multiple studies and allow us to explore patterns of diversity at an unprecedented scale. The result is both a reference database giving global context to DNA sequence data and a framework for incorporating data from future studies, fostering increasingly complete characterization of Earth’s microbial diversity
A communal catalogue reveals Earth's multiscale microbial diversity
Our growing awareness of the microbial world's importance and diversity contrasts starkly with our limited understanding of its fundamental structure. Despite recent advances in DNA sequencing, a lack of standardized protocols and common analytical frameworks impedes comparisons among studies, hindering the development of global inferences about microbial life on Earth. Here we present a meta-analysis of microbial community samples collected by hundreds of researchers for the Earth Microbiome Project. Coordinated protocols and new analytical methods, particularly the use of exact sequences instead of clustered operational taxonomic units, enable bacterial and archaeal ribosomal RNA gene sequences to be followed across multiple studies and allow us to explore patterns of diversity at an unprecedented scale. The result is both a reference database giving global context to DNA sequence data and a framework for incorporating data from future studies, fostering increasingly complete characterization of Earth's microbial diversity.Peer reviewe
Effects of a high-dose 24-h infusion of tranexamic acid on death and thromboembolic events in patients with acute gastrointestinal bleeding (HALT-IT): an international randomised, double-blind, placebo-controlled trial
Background: Tranexamic acid reduces surgical bleeding and reduces death due to bleeding in patients with trauma.
Meta-analyses of small trials show that tranexamic acid might decrease deaths from gastrointestinal bleeding. We
aimed to assess the effects of tranexamic acid in patients with gastrointestinal bleeding.
Methods: We did an international, multicentre, randomised, placebo-controlled trial in 164 hospitals in 15 countries.
Patients were enrolled if the responsible clinician was uncertain whether to use tranexamic acid, were aged above the
minimum age considered an adult in their country (either aged 16 years and older or aged 18 years and older), and
had significant (defined as at risk of bleeding to death) upper or lower gastrointestinal bleeding. Patients were
randomly assigned by selection of a numbered treatment pack from a box containing eight packs that were identical
apart from the pack number. Patients received either a loading dose of 1 g tranexamic acid, which was added to
100 mL infusion bag of 0·9% sodium chloride and infused by slow intravenous injection over 10 min, followed by a
maintenance dose of 3 g tranexamic acid added to 1 L of any isotonic intravenous solution and infused at 125 mg/h
for 24 h, or placebo (sodium chloride 0·9%). Patients, caregivers, and those assessing outcomes were masked to
allocation. The primary outcome was death due to bleeding within 5 days of randomisation; analysis excluded patients
who received neither dose of the allocated treatment and those for whom outcome data on death were unavailable.
This trial was registered with Current Controlled Trials, ISRCTN11225767, and ClinicalTrials.gov, NCT01658124.
Findings: Between July 4, 2013, and June 21, 2019, we randomly allocated 12 009 patients to receive tranexamic acid
(5994, 49·9%) or matching placebo (6015, 50·1%), of whom 11 952 (99·5%) received the first dose of the allocated
treatment. Death due to bleeding within 5 days of randomisation occurred in 222 (4%) of 5956 patients in the
tranexamic acid group and in 226 (4%) of 5981 patients in the placebo group (risk ratio [RR] 0·99, 95% CI 0·82–1·18).
Arterial thromboembolic events (myocardial infarction or stroke) were similar in the tranexamic acid group and
placebo group (42 [0·7%] of 5952 vs 46 [0·8%] of 5977; 0·92; 0·60 to 1·39). Venous thromboembolic events (deep vein
thrombosis or pulmonary embolism) were higher in tranexamic acid group than in the placebo group (48 [0·8%] of
5952 vs 26 [0·4%] of 5977; RR 1·85; 95% CI 1·15 to 2·98).
Interpretation: We found that tranexamic acid did not reduce death from gastrointestinal bleeding. On the basis of our
results, tranexamic acid should not be used for the treatment of gastrointestinal bleeding outside the context of a
randomised trial
Whole-genome sequencing reveals host factors underlying critical COVID-19
Critical COVID-19 is caused by immune-mediated inflammatory lung injury. Host genetic variation influences the development of illness requiring critical care1 or hospitalization2–4 after infection with SARS-CoV-2. The GenOMICC (Genetics of Mortality in Critical Care) study enables the comparison of genomes from individuals who are critically ill with those of population controls to find underlying disease mechanisms. Here we use whole-genome sequencing in 7,491 critically ill individuals compared with 48,400 controls to discover and replicate 23 independent variants that significantly predispose to critical COVID-19. We identify 16 new independent associations, including variants within genes that are involved in interferon signalling (IL10RB and PLSCR1), leucocyte differentiation (BCL11A) and blood-type antigen secretor status (FUT2). Using transcriptome-wide association and colocalization to infer the effect of gene expression on disease severity, we find evidence that implicates multiple genes—including reduced expression of a membrane flippase (ATP11A), and increased expression of a mucin (MUC1)—in critical disease. Mendelian randomization provides evidence in support of causal roles for myeloid cell adhesion molecules (SELE, ICAM5 and CD209) and the coagulation factor F8, all of which are potentially druggable targets. Our results are broadly consistent with a multi-component model of COVID-19 pathophysiology, in which at least two distinct mechanisms can predispose to life-threatening disease: failure to control viral replication; or an enhanced tendency towards pulmonary inflammation and intravascular coagulation. We show that comparison between cases of critical illness and population controls is highly efficient for the detection of therapeutically relevant mechanisms of disease
Sex-biased weaning and early childhood diet among middle holocene hunter-gatherers in Central California
This article evaluates age of weaning and early childhood diets of eight males and nine females from a Middle Holocene (4300-3000 BP) site in Central California, CA-CCO-548. All individuals died as adults. δ(15) N values from serial sections of dentin collagen in first molars suggest females were fully weaned, on average, by 3.6 years of age, about 0.4 years later than males in the sample, suggesting possible greater parental investment in female offspring. However, throughout childhood females consumed lower trophic-level foods than males. This could indicate greater investment in males through provisioning of higher quality foods, or alternatively, some degree of independent foraging by males starting as early as 2 to 3 years of age. Even as adults, these same males and females consumed a different range of foods as indicated by their bone collagen δ(13) C and δ(15) N values. Overall, the data suggest children were enculturated early into their respective gendered diets, with girls consuming greater amounts of plant foods and boys consuming greater amounts of higher-trophic level fish and meat protein
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