1,536 research outputs found
Hydroxychloroquine/chloroquine for the treatment of hospitalized patients with COVID-19: An individual participant data meta-analysis
BACKGROUND: Results from observational studies and randomized clinical trials (RCTs) have led to the consensus that hydroxychloroquine (HCQ) and chloroquine (CQ) are not effective for COVID-19 prevention or treatment. Pooling individual participant data, including unanalyzed data from trials terminated early, enables more detailed investigation of the efficacy and safety of HCQ/CQ among subgroups of hospitalized patients.
METHODS: We searched ClinicalTrials.gov in May and June 2020 for US-based RCTs evaluating HCQ/CQ in hospitalized COVID-19 patients in which the outcomes defined in this study were recorded or could be extrapolated. The primary outcome was a 7-point ordinal scale measured between day 28 and 35 post enrollment; comparisons used proportional odds ratios. Harmonized de-identified data were collected via a common template spreadsheet sent to each principal investigator. The data were analyzed by fitting a prespecified Bayesian ordinal regression model and standardizing the resulting predictions.
RESULTS: Eight of 19 trials met eligibility criteria and agreed to participate. Patient-level data were available from 770 participants (412 HCQ/CQ vs 358 control). Baseline characteristics were similar between groups. We did not find evidence of a difference in COVID-19 ordinal scores between days 28 and 35 post-enrollment in the pooled patient population (odds ratio, 0.97; 95% credible interval, 0.76-1.24; higher favors HCQ/CQ), and found no convincing evidence of meaningful treatment effect heterogeneity among prespecified subgroups. Adverse event and serious adverse event rates were numerically higher with HCQ/CQ vs control (0.39 vs 0.29 and 0.13 vs 0.09 per patient, respectively).
CONCLUSIONS: The findings of this individual participant data meta-analysis reinforce those of individual RCTs that HCQ/CQ is not efficacious for treatment of COVID-19 in hospitalized patients
Methods for Integrating Trials and Non-Experimental Data to Examine Treatment Effect Heterogeneity
Estimating treatment effects conditional on observed covariates can improve
the ability to tailor treatments to particular individuals. Doing so
effectively requires dealing with potential confounding, and also enough data
to adequately estimate effect moderation. A recent influx of work has looked
into estimating treatment effect heterogeneity using data from multiple
randomized controlled trials and/or observational datasets. With many new
methods available for assessing treatment effect heterogeneity using multiple
studies, it is important to understand which methods are best used in which
setting, how the methods compare to one another, and what needs to be done to
continue progress in this field. This paper reviews these methods broken down
by data setting: aggregate-level data, federated learning, and individual
participant-level data. We define the conditional average treatment effect and
discuss differences between parametric and nonparametric estimators, and we
list key assumptions, both those that are required within a single study and
those that are necessary for data combination. After describing existing
approaches, we compare and contrast them and reveal open areas for future
research. This review demonstrates that there are many possible approaches for
estimating treatment effect heterogeneity through the combination of datasets,
but that there is substantial work to be done to compare these methods through
case studies and simulations, extend them to different settings, and refine
them to account for various challenges present in real data
Morphological and quantitative analysis of BCL6 expression in human colorectal carcinogenesis.
The aim of the present study was to determine whether BCL6 is expressed during malignant transformation of the large bowel and to assess whether, and to what extent, immunoreactivity is related to the different stages of neoplastic progression. Samples of normal colorectal mucosa (n=22), microadenomas (n=22) and colorectal cancer (n=22), were analyzed by immunohistochemistry, immunofluorescence coupled with confocal microscopy and western blotting. Our results clearly outlined the marked increase occurring in both intensity and density of BCL6 protein expression in the normal mucosa-microadenoma-carcinoma sequence. Immunohistochemistry and immunofluorescence analyses showed that BCL6 is expressed at low levels in normal mucosa and increases in microadenoma and in cancer with statistical significance. These results were confirmed by western blotting data. The increasing expression of BCL6 in human colorectal cancer development suggests the involvement of BCL6 in tumor progression, from the earliest stages of carcinogenesis with significant increase in cancer. The enhanced understanding of the biological role of BCL6, previously shown to exert a key role in lymphomagenesis, may lead to a re-evaluation of this protein and may highlight the importance of performing further studies in order to identify novel therapeutic targets for colorectal cancer
Functional characteristics of calcitonin gene-related peptide receptors in human Ewing's sarcoma WE-68 cells
AbstractCalcitonin gene-related peptide (CGRP) receptor activity was studied in WE-68 human Ewing's sarcoma cells. 125I-human CGRP bound in a time-dependent, reversible and saturable manner. Scatchard plots were compatible with the presence of a homogenous population of CGRP receptors with high affinity (Kd = 15 pM, and Bmax = 1.9 fmolmg protein). The potency order of unlabeled peptides, in the presence of radioligand, was: human CGRP-II > human CGRP = chick CGRP > rat CGRP = rat [Tyro]CGRP > human [Tyro] CGRP > > salmon calcitonin (CT) > rat [Tyro]CGRP-(28-37). Each peptide except CT and [Tyio]CGRP-(28-37) stimulated cyclic AMP generation in a concentration-dependent manner, and the relative potencies paralleled their relative ability in inhibiting 125I-human CGRP binding. We conclude that WE-68 Ewing's sarcoma cells express genuine CGRP receptors which upon activation lead to stimulation of cyclic AMP formation.Calcitonin gene-related peptide; Calcitonin; cyclic AMP; (Human; Ewing's sarcoma cell
Intra-operative gallbladder scoring predicts conversion of laparoscopic to open cholecystectomy: a WSES prospective collaborative study
Abstract Introduction Laparoscopic cholecystectomy, the gold-standard approach for cholecystectomy, has surprisingly variable outcomes and conversion rates. Only recently has operative grading been reported to define disease severity and few have been validated. This multicentre, multinational study assessed an operative scoring system to assess its ability to predict the need for conversion from laparoscopic to open cholecystectomy. Methods A prospective, web-based, ethically approved study was established by WSES with a 10-point gallbladder operative scoring system; enrolling patients undergoing elective or emergency laparoscopic cholecystectomy between January 2016 and December 2017. Gallbladder surgery was considered easy if the G10 score <â2, moderate (2 âŠÂ 4), difficult (5 âŠÂ 7) and extreme (8 âŠÂ 10). Demographics about the patients, surgeons and operative procedures, use of cholangiography and conversion rates were recorded. Results Five hundred four patients, mean age 53.5 (range 18â89), were enrolled by 55 surgeons in 16 countries. Surgery was performed by consultants in 70% and was elective in (56%) with a mean operative time of 78.7 min (range 15-400). The mean G10 score was 3.21, with 22% deemed to have difficult or extreme surgical gallbladders, and 71/504 patients were converted. The G10 score was 2.98 in those completed laparoscopically and 4.65 in the 71/504 (14%) converted. (pâ<â 0.0001; AUC 0.772 (CI 0.719â0.825). The optimal cut-off point of 0.067 (score of 3) was identified in G10 vs conversion to open cholecystectomy. Conversion occurred in 33% of patients with G10 scores of â„â5. The four variables statistically predictive of conversion were GB appearanceâcompletely buried GB, impacted stone, bile or pus outside GB and fistula. Conclusion The G10 operative scores provide simple grading of operative cholecystectomy and are predictive of the need to convert to open cholecystectomy. Broader adaptation and validation may provide a benchmark to understand and improve care and afford more standardisation in global comparisons of care for cholecystectomy
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
Roadmap on photonic metasurfaces
Funding: C.R. and U.L. acknowledge support through the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germanyâs Excellence Strategy via the Excellence Cluster 3D Matter Made to Order (EXC-2082/1, Grant No. 390761711). A.B.E. acknowledges support through the Cluster of Excellence PhoenixD (EXC 2122, Project ID No. 390833453). I.F.-C. and C.R. acknowledge support through the CRC Waves: Analysis and Numerics (SFB 1173, Grant No. 258734477. K.A. acknowledges funding from the Swiss National Science Foundation (Project No. PZ00P2_193221).Here we present a roadmap on Photonic metasurfaces. This document consists of a number of perspective articles on different applications, challenge areas or technologies underlying photonic metasurfaces. Each perspective will introduce the topic, present a state of the art as well as give an insight into the future direction of the subfield.Peer reviewe
A third generation vaccine for human visceral leishmaniasis and post kala azar dermal leishmaniasis : First-in-human trial of ChAd63-KH
BACKGROUND: Visceral leishmaniasis (VL or kala azar) is the most serious form of human leishmaniasis, responsible for over 20,000 deaths annually, and post kala azar dermal leishmaniasis (PKDL) is a stigmatizing skin condition that often occurs in patients after successful treatment for VL. Lack of effective or appropriately targeted cell mediated immunity, including CD8+ T cell responses, underlies the progression of VL and progression to PKDL, and can limit the therapeutic efficacy of anti-leishmanial drugs. Hence, in addition to the need for prophylactic vaccines against leishmaniasis, the development of therapeutic vaccines for use alone or in combined immuno-chemotherapy has been identified as an unmet clinical need. Here, we report the first clinical trial of a third-generation leishmaniasis vaccine, developed intentionally to induce Leishmania-specific CD8+ T cells. METHODS: We conducted a first-in-human dose escalation Phase I trial in 20 healthy volunteers to assess the safety, tolerability and immunogenicity of a prime-only adenoviral vaccine for human VL and PKDL. ChAd63-KH is a replication defective simian adenovirus expressing a novel synthetic gene (KH) encoding two Leishmania proteins KMP-11 and HASPB. Uniquely, the latter was engineered to reflect repeat domain polymorphisms and arrangements identified from clinical isolates. We monitored innate immune responses by whole blood RNA-Seq and antigen specific CD8+ T cell responses by IFNÎł ELISPOT and intracellular flow cytometry. FINDINGS: ChAd63-KH was safe at intramuscular doses of 1x1010 and 7.5x1010 vp. Whole blood transcriptomic profiling indicated that ChAd63-KH induced innate immune responses characterized by an interferon signature and the presence of activated dendritic cells. Broad and quantitatively robust CD8+ T cell responses were induced by vaccination in 100% (20/20) of vaccinated subjects. CONCLUSION: The results of this study support the further development of ChAd63-KH as a novel third generation vaccine for VL and PKDL. TRIAL REGISTRATION: This clinical trial (LEISH1) was registered at EudraCT (2012-005596-14) and ISRCTN (07766359)
Infected pancreatic necrosis: outcomes and clinical predictors of mortality. A post hoc analysis of the MANCTRA-1 international study
: The identification of high-risk patients in the early stages of infected pancreatic necrosis (IPN) is critical, because it could help the clinicians to adopt more effective management strategies. We conducted a post hoc analysis of the MANCTRA-1 international study to assess the association between clinical risk factors and mortality among adult patients with IPN. Univariable and multivariable logistic regression models were used to identify prognostic factors of mortality. We identified 247 consecutive patients with IPN hospitalised between January 2019 and December 2020. History of uncontrolled arterial hypertension (pâ=â0.032; 95% CI 1.135-15.882; aOR 4.245), qSOFA (pâ=â0.005; 95% CI 1.359-5.879; aOR 2.828), renal failure (pâ=â0.022; 95% CI 1.138-5.442; aOR 2.489), and haemodynamic failure (pâ=â0.018; 95% CI 1.184-5.978; aOR 2.661), were identified as independent predictors of mortality in IPN patients. Cholangitis (pâ=â0.003; 95% CI 1.598-9.930; aOR 3.983), abdominal compartment syndrome (pâ=â0.032; 95% CI 1.090-6.967; aOR 2.735), and gastrointestinal/intra-abdominal bleeding (pâ=â0.009; 95% CI 1.286-5.712; aOR 2.710) were independently associated with the risk of mortality. Upfront open surgical necrosectomy was strongly associated with the risk of mortality (pâ<â0.001; 95% CI 1.912-7.442; aOR 3.772), whereas endoscopic drainage of pancreatic necrosis (pâ=â0.018; 95% CI 0.138-0.834; aOR 0.339) and enteral nutrition (pâ=â0.003; 95% CI 0.143-0.716; aOR 0.320) were found as protective factors. Organ failure, acute cholangitis, and upfront open surgical necrosectomy were the most significant predictors of mortality. Our study confirmed that, even in a subgroup of particularly ill patients such as those with IPN, upfront open surgery should be avoided as much as possible. Study protocol registered in ClinicalTrials.Gov (I.D. Number NCT04747990)
VERY HIGH ENERGY Îł-RAYS from the UNIVERSE'S MIDDLE AGE: DETECTION of the z = 0.940 BLAZAR PKS 1441+25 with MAGIC
The flat-spectrum radio quasar PKS 1441+25 at a redshift of z = 0.940 is detected between 40 and 250 GeV with a significance of 25.5Ï using the MAGIC telescopes. Together with the gravitationally lensed blazar QSO B0218+357 (z = 0.944), PKS 1441+25 is the most distant very high energy (VHE) blazar detected to date. The observations were triggered by an outburst in 2015 April seen at GeV energies with the Large Area Telescope on board Fermi. Multi-wavelength observations suggest a subdivision of the high state into two distinct flux states. In the band covered by MAGIC, the variability timescale is estimated to be 6.4 ±1.9 days. Modeling the broadband spectral energy distribution with an external Compton model, the location of the emitting region is understood as originating in the jet outside the broad-line region (BLR) during the period of high activity, while being partially within the BLR during the period of low (typical) activity. The observed VHE spectrum during the highest activity is used to probe the extragalactic background light at an unprecedented distance scale for ground-based gamma-ray astronomy
- âŠ