216 research outputs found
Definitions of massive transfusion in adults with critical bleeding: a systematic review.
BACKGROUND: Definitions for massive transfusion (MT) vary widely between studies, contributing to challenges in interpretation of research findings and practice evaluation. In this first systematic review, we aimed to identify all MT definitions used in randomised controlled trials (RCTs) to date to inform the development of consensus definitions for MT. METHODS: We systematically searched the following databases for RCTs from inception until 11 August 2022: MEDLINE, Embase, Cochrane Central Register of Controlled Trials (CENTRAL), PubMed, Cumulative Index to Nursing and Allied Health Literature, and Transfusion Evidence Library. Ongoing trials were sought from CENTRAL, ClinicalTrials.gov, and World Health Organisation International Clinical Trials Registry Platform. To be eligible for inclusion, studies had to fulfil all the following three criteria: (1) be an RCT; (2) include an adult patient population with major bleeding who had received, or were anticipated to receive, an MT in any clinical setting; and (3) specify a definition for MT as an inclusion criterion or outcome measure. RESULTS: Of the 8,458 distinct references identified, 30 trials were included for analysis (19 published, 11 ongoing). Trauma was the most common clinical setting in published trials, while for ongoing trials, it was obstetrics. A total of 15 different definitions of MT were identified across published and ongoing trials, varying greatly in cut-offs for volume transfused and time period. Almost all definitions specified the number of red blood cells (RBCs) within a set time period, with none including plasma, platelets or other haemostatic agents that are part of contemporary transfusion resuscitation. For completed trials, the most commonly used definition was transfusion of ≥ 10 RBC units in 24 h (9/19, all in trauma), while for ongoing trials it was 3-5 RBC units (n = 7), with the timing for transfusion being poorly defined, or in some trials not provided at all (n = 5). CONCLUSIONS: Transfusion of ≥ 10 RBC units within 24 h was the most commonly used definition in published RCTs, while lower RBC volumes are being used in ongoing RCTs. Any consensus definitions should reflect the need to incorporate different blood components/products for MT and agree on whether a 'one-size-fits-all' approach should be used across different clinical settings
Relativistic suppression of Auger recombination in Weyl semimetals
Auger recombination (AR) being electron-hole annihilation with
energy-momentum transfer to another carrier is believed to speed up in
materials with small band gap. We theoretically show that this rule is violated
in gapless three-dimensional materials with ultra-relativistic electron-hole
dispersion, Weyl semimetals (WSM). Namely, AR is prohibited by energy-momentum
conservation laws in prototypical WSM with a single Weyl node, even in the
presence of anisotropy and tilt. In real multi-node WSM, the geometric
dissimilarity of nodal dispersions enables weak inter-node AR, which is further
suppressed by strong screening due to large number of nodes. While partial AR
rates between the nodes of the same node group are mutually equal, the
inter-group processes are non-reciprocal, so that one of groups is
geometrically protected from AR. Our calculations show that geometrical
protection can help prolonging AR lifetime by the two orders of magnitude, up
to the level of nanoseconds.Comment: 6 pages + 10 pages of supporting informatio
KSR2 mutations are associated with obesity, insulin resistance, and impaired cellular fuel oxidation.
Kinase suppressor of Ras 2 (KSR2) is an intracellular scaffolding protein involved in multiple signaling pathways. Targeted deletion of Ksr2 leads to obesity in mice, suggesting a role in energy homeostasis. We explored the role of KSR2 in humans by sequencing 2,101 individuals with severe early-onset obesity and 1,536 controls. We identified multiple rare variants in KSR2 that disrupt signaling through the Raf-MEKERK pathway and impair cellular fatty acid oxidation and glucose oxidation in transfected cells; effects that can be ameliorated by the commonly prescribed antidiabetic drug, metformin. Mutation carriers exhibit hyperphagia in childhood, low heart rate, reduced basal metabolic rate and severe insulin resistance. These data establish KSR2 as an important regulator of energy intake, energy expenditure, and substrate utilization in humans. Modulation of KSR2-mediated effects may represent a novel therapeutic strategy for obesity and type 2 diabetes.This work was supported by the Wellcome Trust
(098497/Z/12/Z; 077016/Z/05/Z; 096106/Z/11/Z) (ISF and LRP), Medical
Research Council (MC_U106179471) (NW), NIHR Cambridge Biomedical
Research Centre (ISF, IB and SOR), and European Research Council (ISF).
This study makes use of data generated by the UK10K Consortium
(WT091310). A full list of the investigators who contributed to the generation
of the data is available from http://www.UK10K.org.This is the final published version. It first appeared at http://www.cell.com/abstract/S0092-8674%2813%2901276-2
In silico design and biological evaluation of a dual specificity kinase inhibitor targeting cell cycle progression and angiogenesis
Methodology: We have utilized a rational in silico-based approach to demonstrate the design and study of a novel compound that acts as a dual inhibitor of vascular endothelial growth factor receptor 2 (VEGFR2) and cyclin-dependent kinase 1 (CDK1). This compound acts by simultaneously inhibiting pro-Angiogenic signal transduction and cell cycle progression in primary endothelial cells. JK-31 displays potent in vitro activity against recombinant VEGFR2 and CDK1/cyclin B proteins comparable to previously characterized inhibitors. Dual inhibition of the vascular endothelial growth factor A (VEGF-A)-mediated signaling response and CDK1-mediated mitotic entry elicits anti-Angiogenic activity both in an endothelial-fibroblast co-culture model and a murine ex vivo model of angiogenesis
Long-Term Effects of Autologous Bone Marrow Stem Cell Treatment in Acute Myocardial Infarction: Factors That May Influence Outcomes
AIMS: To investigate whether there are important sources of heterogeneity between the findings of different clinical trials which administer autologous stem cell treatment for acute myocardial infarction (AMI) and to evaluate what factors may influence the long-term effects of this treatment. METHODS AND RESULTS: MEDLINE (1950-January 2011), EMBASE (1974-January 2011), CENTRAL (The Cochrane Library 2011, Issue 1), CINAHL (1982-January 2011), and ongoing trials registers were searched for randomised trials of bone marrow stem cells as treatment for AMI. Hand-searching was used to screen recent, relevant conference proceedings (2005-2010/11). Meta-analyses were conducted using random-effects models and heterogeneity between subgroups was assessed using chi-squared tests. Planned analyses included length of follow-up, timing of cell infusion and dose, patient selection, small trial size effect, methodological quality, loss of follow-up and date of publication. Thirty-three trials with a total of 1,765 participants were included. There was no evidence of bias due to publication or time-lag, methodological quality of included studies, participant drop-out, duration of follow-up or date of the first disclosure of results. However, in long-term follow-ups the treatment seemed more effective when administered at doses greater than 10(8) cells and to patients with more severe heart dysfunction. CONCLUSIONS: Evaluation of heterogeneity between trials has not identified significant sources of bias in this study. However, clinical differences between trials are likely to exist which should be considered when undertaking future trials
Erratum to: 36th International Symposium on Intensive Care and Emergency Medicine
[This corrects the article DOI: 10.1186/s13054-016-1208-6.]
Perinatal asphyxia: current status and approaches towards neuroprotective strategies, with focus on sentinel proteins
Delivery is a stressful and risky event menacing the newborn. The mother-dependent respiration has to be replaced by autonomous pulmonary breathing immediately after delivery. If delayed, it may lead to deficient oxygen supply compromising survival and development of the central nervous system. Lack of oxygen availability gives rise to depletion of NAD+ tissue stores, decrease of ATP formation, weakening of the electron transport pump and anaerobic metabolism and acidosis, leading necessarily to death if oxygenation is not promptly re-established. Re-oxygenation triggers a cascade of compensatory biochemical events to restore function, which may be accompanied by improper homeostasis and oxidative stress. Consequences may be incomplete recovery, or excess reactions that worsen the biological outcome by disturbed metabolism and/or imbalance produced by over-expression of alternative metabolic pathways. Perinatal asphyxia has been associated with severe neurological and psychiatric sequelae with delayed clinical onset. No specific treatments have yet been established. In the clinical setting, after resuscitation of an infant with birth asphyxia, the emphasis is on supportive therapy. Several interventions have been proposed to attenuate secondary neuronal injuries elicited by asphyxia, including hypothermia. Although promising, the clinical efficacy of hypothermia has not been fully demonstrated. It is evident that new approaches are warranted. The purpose of this review is to discuss the concept of sentinel proteins as targets for neuroprotection. Several sentinel proteins have been described to protect the integrity of the genome (e.g. PARP-1; XRCC1; DNA ligase IIIα; DNA polymerase β, ERCC2, DNA-dependent protein kinases). They act by eliciting metabolic cascades leading to (i) activation of cell survival and neurotrophic pathways; (ii) early and delayed programmed cell death, and (iii) promotion of cell proliferation, differentiation, neuritogenesis and synaptogenesis. It is proposed that sentinel proteins can be used as markers for characterising long-term effects of perinatal asphyxia, and as targets for novel therapeutic development and innovative strategies for neonatal care
Nurses' perceptions of aids and obstacles to the provision of optimal end of life care in ICU
Contains fulltext :
172380.pdf (publisher's version ) (Open Access
Ear drops for the removal of ear wax.
BACKGROUND: Problems attributed to the accumulation of wax (cerumen) are among the most common reasons for people to present to their general practitioners with ear trouble. Treatment for this condition often involves use of a wax softening agent (cerumenolytic) to disperse the cerumen, reduce the need for, or facilitate syringing, but there is no consensus on the effectiveness of the variety of cerumenolytics in use. OBJECTIVES: To assess the effectiveness of ear drops (cerumenolytics) for the removal of symptomatic ear wax. SEARCH STRATEGY: We searched the Cochrane Ear, Nose and Throat Disorders Group Trials Register; the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, 2008 issue 2); MEDLINE; EMBASE; CINAHL; ISI Proceedings; Cambridge Scientific Abstracts; mRCT and additional sources for published and unpublished trials. The date of the most recent search was April 2008. SELECTION CRITERIA: We identified all randomised controlled trials in which a cerumenolytic was compared with no treatment, a placebo, or other cerumenolytics in participants with obstructing or impacted ear wax, and in which the proportion of participants with sufficient clearance of the external canal to make further mechanical clearance unnecessary (primary outcome measure) was stated or calculable. DATA COLLECTION AND ANALYSIS: The two authors reviewed all the retrieved trials and applied the inclusion criteria independently. MAIN RESULTS: Nine trials satisfied the inclusion criteria. In all, 679 participants received one of 11 different cerumenolytics. One trial compared active treatments with no treatment, three compared active treatments with water or a saline 'placebo', and all nine trials compared two or more active treatments. Eight trials included syringing as a secondary intervention.Overall, results were inconclusive. The majority of comparisons showed no difference between treatments. Meta-analysis of two high quality trials produced a statistical difference in favour of triethanolamine polypeptide over saline in preventing the need for syringing, but no other significant differences between treatments.In three trials of high to moderate quality, no difference was found between the effectiveness of either sodium bicarbonate ear drops, chlorbutanol, triethanolamine polypeptide oleate condensate or docusate sodium liquid versus a sterile water or saline 'placebo'.One trial of moderate methodological quality found all three treatments - sodium bicarbonate ear drops, chlorbutanol and sterile water - to be significantly better than no treatment at preventing the need for syringing.None of the higher quality trials demonstrated superiority of one agent over another in direct comparisons. AUTHORS' CONCLUSIONS: Trials have been heterogeneous and generally of low or moderate quality, making it difficult to offer any definitive recommendations on the effectiveness of cerumenolytics for the removal of symptomatic ear wax. Using drops of any sort appears to be better than no treatment, but it is uncertain if one type of drop is any better than another. Future trials should be of high methodological quality, have large sample sizes, and compare both oil-based and water-based solvents with placebo, no treatment or both
- …