1,059 research outputs found
Comparison of Sanger sequencing for hepatitis C virus genotyping with a commercial line probe assay in a tertiary hospital
Background: The technique most frequently used to genotype HCV is quantitative RT-PCR. This technique is unable to provide an accurate genotype/subtype for many samples; we decided to develop an in-house method with the goal of accurately identifying the genotype of all samples. As a Belgium National Centre of reference for hepatitis, we developed in-house sequencing not only for 5'UTR and core regions starting from VERSANT LiPA amplicons but also for NS5B regions. The sequencing of VERSANT LiPA amplicons might be useful for many laboratories worldwide using the VERSANT LiPA assay to overcome undetermined results.
Methods: 100 samples from Hepatitis C virus infected patients analysed by the VERSANT HCV Genotype 2.0 LiPA Assay covering frequent HCV types and subtypes were included in this study. NS5B, 5'UTR and Core home-made sequencing were then performed on these samples. The sequences obtained were compared with the HCV genomic BLAST bank.
Results: All the samples were characterised by the VERSANT LiPA assay (8 G1a, 17 G1b, 6 G2, 11 G3, 13 G4, and 10 G6). It was not possible to discriminate between G6 and G1 by the VERSANT LiPA assay for 8 samples and 27 had an undetermined genotype. Forty-one samples were sequenced for the three regions: NS5B, 5'UTR and Core. Twenty-three samples were sequenced for two regions: 5 UTR and Core and 36 samples were sequenced only for NS5B. Of the 100 samples included, 64 samples were analysed for 5'UTR and Core sequencing and 79 samples were analysed for NS5B sequencing. The global agreement between VERSANT LiPA assay and sequencing was greater than 95%.
Conclusions: In this study, we describe a new, original method to confirm HCV genotypes of samples not discriminated by a commercial assay, using amplicons already obtained by the screening method, here the VERSANT LiPA assay. This method thus saves one step if a confirmation assay is needed and might be of usefulness for many laboratories worldwide performing VERSANT LiPA assay in particular
Prevalence and mechanisms of resistance to carbapenems in Enterobacteriaceae
Objectives: To determine the point prevalence of carbapenem-non-susceptible Enterobacteriaceae (CNSE) and carbapenemase-producing Enterobacteriaceae (CPE) isolates among hospitalized patients in Belgium.
Methods: Twenty-four hospital-based laboratories prospectively collected 200 non-duplicated Enterobacteriaceae isolates from clinical specimens of hospitalized patients over a 2 month period. All isolates were screened locally for decreased susceptibility to carbapenem drugs using a disc diffusion method according to CLSI interpretative criteria. CNSE strains were referred centrally for confirmation of carbapenemase by phenotypic and molecular testing.
Results: From February to April 2012, 158 of the 4564 screened Enterobacteriaceae isolates were categorized as non-susceptible to carbapenems, resulting in a point prevalence of CNSE of 3.5% (95% CI: 2.9%–4.2%; range per centre: 0.5%–8.5%). Of the 125 referred CNSE isolates, 11 Klebsiella pneumoniae isolates [OXA-48 (n=7), KPC type (n=3) and NDM type (n=1)], 1 OXA-48-positive Escherichia coli isolate and 1 KPC-positive Klebsiella oxytoca isolate were detected in eight hospitals. None of the 72 carbapenem-non-susceptible Enterobacter spp. isolates were confirmed as CPE. The minimal estimated point prevalence of CPE isolates was 0.28% (13/ 4564; 95% CI: 0.13%–0.44%) overall (range per centre: 0%–1.5%).
Conclusions: Despite the overall low prevalence of CNSE found in this study, the detection of CPE isolates in one-third of the participating centres raises concerns and highly suggests the spread and establishment of CPE in Belgian hospitals
Correlation between cytotoxicity induced by Pseudomonas aeruginosa clinical isolates from acute infections and IL-1β secretion in a model of human THP-1 monocytes
Type III secretion system (T3SS) in Pseudomonas aeruginosa is associated with poor clinical outcome in acute infections. T3SS allows for injection of bacterial exotoxins (e.g. ExoU or ExoS) into the host cell, causing cytotoxicity. It also activates the cytosolic NLRC4 inflammasome, activating caspase-1, inducing cytotoxicity and release of mature IL-1β, which impairs bacterial clearance. In addition, flagellum-mediated motility has been suggested to also modulate inflammasome response and IL-1β release. Yet the capacity of clinical isolates to induce IL-1β release and its relation with cytotoxicity have never been investigated. Using 20 clinical isolates from acute infections with variable T3SS expression levels and human monocytes, our aim was to correlate IL-1β release with toxin expression, flagellar motility and cytotoxicity. ExoU-producing isolates caused massive cell death but minimal release of IL-1β, while those expressing T3SS but not ExoU (i.e. expressing ExoS or no toxins) induced caspase-1 activation and IL-1β release, the level of which was correlated with cytotoxicity. Both effects were prevented by a specific caspase-1 inhibitor. Flagellar motility was not correlated with cytotoxicity or IL-1β release. No apoptosis was detected. Thus, T3SS cytotoxicity is accompanied by a modification in cytokine balance for P. aeruginosa clinical isolates that do not express Exo
Surgical site infection after gastrointestinal surgery in high-income, middle-income, and low-income countries: a prospective, international, multicentre cohort study
Background: Surgical site infection (SSI) is one of the most common infections associated with health care, but its importance as a global health priority is not fully understood. We quantified the burden of SSI after gastrointestinal surgery in countries in all parts of the world.
Methods: This international, prospective, multicentre cohort study included consecutive patients undergoing elective or emergency gastrointestinal resection within 2-week time periods at any health-care facility in any country. Countries with participating centres were stratified into high-income, middle-income, and low-income groups according to the UN's Human Development Index (HDI). Data variables from the GlobalSurg 1 study and other studies that have been found to affect the likelihood of SSI were entered into risk adjustment models. The primary outcome measure was the 30-day SSI incidence (defined by US Centers for Disease Control and Prevention criteria for superficial and deep incisional SSI). Relationships with explanatory variables were examined using Bayesian multilevel logistic regression models. This trial is registered with ClinicalTrials.gov, number NCT02662231.
Findings: Between Jan 4, 2016, and July 31, 2016, 13 265 records were submitted for analysis. 12 539 patients from 343 hospitals in 66 countries were included. 7339 (58·5%) patient were from high-HDI countries (193 hospitals in 30 countries), 3918 (31·2%) patients were from middle-HDI countries (82 hospitals in 18 countries), and 1282 (10·2%) patients were from low-HDI countries (68 hospitals in 18 countries). In total, 1538 (12·3%) patients had SSI within 30 days of surgery. The incidence of SSI varied between countries with high (691 [9·4%] of 7339 patients), middle (549 [14·0%] of 3918 patients), and low (298 [23·2%] of 1282) HDI (p < 0·001). The highest SSI incidence in each HDI group was after dirty surgery (102 [17·8%] of 574 patients in high-HDI countries; 74 [31·4%] of 236 patients in middle-HDI countries; 72 [39·8%] of 181 patients in low-HDI countries). Following risk factor adjustment, patients in low-HDI countries were at greatest risk of SSI (adjusted odds ratio 1·60, 95% credible interval 1·05–2·37; p=0·030). 132 (21·6%) of 610 patients with an SSI and a microbiology culture result had an infection that was resistant to the prophylactic antibiotic used. Resistant infections were detected in 49 (16·6%) of 295 patients in high-HDI countries, in 37 (19·8%) of 187 patients in middle-HDI countries, and in 46 (35·9%) of 128 patients in low-HDI countries (p < 0·001).
Interpretation: Countries with a low HDI carry a disproportionately greater burden of SSI than countries with a middle or high HDI and might have higher rates of antibiotic resistance. In view of WHO recommendations on SSI prevention that highlight the absence of high-quality interventional research, urgent, pragmatic, randomised trials based in LMICs are needed to assess measures aiming to reduce this preventable complication
Antibiotic use by clinical presentation across all healthcare providers in rural Burkina Faso: a healthcare visit exit survey
BACKGROUND: To guide antibiotic stewardship interventions, understanding for what indications antibiotics are used is essential. METHODS: In rural Burkina Faso, we measured antibiotic dispensing across all healthcare providers. From October 2021 to February 2022, we surveyed patients in Nanoro district, Burkina Faso, following visits to health centres (3), pharmacies (2), informal medicine vendors (5) and inpatients in health centres. We estimated prevalence of antibiotic use and the proportion of Watch group antibiotics by provider type and by clinical presentation, assessing compliance with WHO's AWaRe Antibiotic Book. We estimated per capita antibiotic use by multiplying prevalence of antibiotic use, mean DDD per adult treatment course, and the rate of healthcare visits per 1000 inhabitants per day, estimated from a prior household survey. RESULTS: Outpatient antibiotic use was more frequent after health centre visits (54.8%, of which 16.5% Watch, n = 1249) than after visits to pharmacies (26.2%, 16.3% Watch, n = 328) and informal medicine vendors (26.9%, 50.0% Watch, n = 349). The frequency of antibiotic use was highest for bronchitis (79.9% antibiotic use, of which 12.6% Watch), malaria (31.9%, 23.1% Watch), gastroenteritis (76.0%, 31.7% Watch), rhinopharyngitis (40.4%, 8.3% Watch) and undifferentiated fever (77.0%, 44.8% Watch). Compliance with WHO AWaRe guidance could have averted at least 68.4% of all Watch antibiotic use in outpatients at health centres. Community-wide, 2.9 DDD (95% CI 1.9-3.9) were used per 1000 adult inhabitants per day. CONCLUSIONS: Most Watch antibiotic use at community level or primary care deviated from WHO guidance. Antibiotic stewardship should focus on key clinical presentations and include primary care and self-medication
Healthcare seeking outside healthcare facilities and antibiotic dispensing patterns in rural Burkina Faso: A mixed methods study
Objective: Optimising antibiotic use is important to limit increasing antibiotic resistance. In rural Burkina Faso, over-the-counter dispensing of antibiotics in community pharmacies and non-licensed medicine retail outlets facilitates self-medication. We investigated its extent, reasons and dispensing patterns. Methods: In an exploratory mixed-method design conducted between October 2020 and December 2021, this study first explored illness perceptions, the range of healthcare providers in communities, antibiotics knowledge and reasons for seeking healthcare outside healthcare facilities. Second, frequencies of illness and healthcare utilisation in the last 3 months were quantitatively measured. Results: Participants distinguished between natural and magico-religious illnesses, according to origins. For illnesses considered to be ‘natural’, healthcare was mainly sought at healthcare facilities, private pharmacies and informal drug outlets. For illnesses considered as magico-religious, traditional healers were mainly visited. Antibiotics were perceived in the community as medicines similar to painkillers. Healthcare-seeking outside healthcare facilities was reported by 660/1973 (33.5%) participants reporting symptoms, including 315 (47.7%) to informal vendors. Healthcare seeking outside facilities was less common for 0–4-year-olds (58/534, 10.9% vs. 379/850, 44.1% for ≥5-year-olds) and decreased with improving socio-economic status (108/237, 45.6% in the lowest quintile; 96/418, 23.0% in the highest). Reported reasons included financial limitation, and also proximity to informal drug vendors, long waiting times at healthcare facilities, and health professionals' non-empathetic attitudes towards their patients. Conclusion: This study highlights the need to facilitate and promote access to healthcare facilities through universal health insurance and patient-centred care including reducing patients' waiting time. Furthermore, community-level antibiotic stewardship programmes should include community pharmacies and informal vendors
Subacute Zinc Administration and L-NAME Caused an Increase of NO, Zinc, Lipoperoxidation, and Caspase-3 during a Cerebral Hypoxia-Ischemia Process in the Rat
Zinc or L-NAME administration has been shown to be protector agents, decreasing oxidative stress and cell death. However, the treatment with zinc and L-NAME by intraperitoneal injection has not been studied. The aim of our work was to study the effect of zinc and L-NAME administration on nitrosative stress and cell death. Male Wistar rats were treated with ZnCl2(2.5 mg/kg each 24 h, for 4 days) and N-ω-nitro-L-arginine-methyl ester (L-NAME, 10 mg/kg) on the day 5 (1 hour before a common carotid-artery occlusion (CCAO)). The temporoparietal cortex and hippocampus were dissected, and zinc, nitrites, and lipoperoxidation were assayed at different times. Cell death was assayed by histopathology using hematoxylin-eosin staining and caspase-3 active by immunostaining. The subacute administration of zinc before CCAO decreases the levels of zinc, nitrites, lipoperoxidation, and cell death in the late phase of the ischemia. L-NAME administration in the rats treated with zinc showed an increase of zinc levels in the early phase and increase of zinc, nitrites, and lipoperoxidation levels, cell death by necrosis, and the apoptosis in the late phase. These results suggest that the use of these two therapeutic strategies increased the injury caused by the CCAO, unlike the alone administration of zinc.</jats:p
Clonal chromosomal mosaicism and loss of chromosome Y in elderly men increase vulnerability for SARS-CoV-2
The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, COVID-19) had an estimated overall case fatality ratio of 1.38% (pre-vaccination), being 53% higher in males and increasing exponentially with age. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, we found 133 cases (1.42%) with detectable clonal mosaicism for chromosome alterations (mCA) and 226 males (5.08%) with acquired loss of chromosome Y (LOY). Individuals with clonal mosaic events (mCA and/or LOY) showed a 54% increase in the risk of COVID-19 lethality. LOY is associated with transcriptomic biomarkers of immune dysfunction, pro-coagulation activity and cardiovascular risk. Interferon-induced genes involved in the initial immune response to SARS-CoV-2 are also down-regulated in LOY. Thus, mCA and LOY underlie at least part of the sex-biased severity and mortality of COVID-19 in aging patients. Given its potential therapeutic and prognostic relevance, evaluation of clonal mosaicism should be implemented as biomarker of COVID-19 severity in elderly people. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, individuals with clonal mosaic events (clonal mosaicism for chromosome alterations and/or loss of chromosome Y) showed an increased risk of COVID-19 lethality
The global abundance of tree palms
Aim Palms are an iconic, diverse and often abundant component of tropical ecosystems that provide many ecosystem services. Being monocots, tree palms are evolutionarily, morphologically and physiologically distinct from other trees, and these differences have important consequences for ecosystem services (e.g., carbon sequestration and storage) and in terms of responses to climate change. We quantified global patterns of tree palm relative abundance to help improve understanding of tropical forests and reduce uncertainty about these ecosystems under climate change. Location Tropical and subtropical moist forests. Time period Current. Major taxa studied Palms (Arecaceae). Methods We assembled a pantropical dataset of 2,548 forest plots (covering 1,191 ha) and quantified tree palm (i.e., ≥10 cm diameter at breast height) abundance relative to co‐occurring non‐palm trees. We compared the relative abundance of tree palms across biogeographical realms and tested for associations with palaeoclimate stability, current climate, edaphic conditions and metrics of forest structure. Results On average, the relative abundance of tree palms was more than five times larger between Neotropical locations and other biogeographical realms. Tree palms were absent in most locations outside the Neotropics but present in >80% of Neotropical locations. The relative abundance of tree palms was more strongly associated with local conditions (e.g., higher mean annual precipitation, lower soil fertility, shallower water table and lower plot mean wood density) than metrics of long‐term climate stability. Life‐form diversity also influenced the patterns; palm assemblages outside the Neotropics comprise many non‐tree (e.g., climbing) palms. Finally, we show that tree palms can influence estimates of above‐ground biomass, but the magnitude and direction of the effect require additional work. Conclusions Tree palms are not only quintessentially tropical, but they are also overwhelmingly Neotropical. Future work to understand the contributions of tree palms to biomass estimates and carbon cycling will be particularly crucial in Neotropical forests
- …
