833 research outputs found

    1-N6-Etheno-ADP-ribosylation of elongation factor-2 by diphtheria toxin

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    AbstractDiphtheria toxin fragment A is able to inhibit protein synthesis in the eukaryotic cell by ADP-ribosylating the diphthamide residue of elongation factor-2 (EF-2) [(1980) J. Biol. Chem. 255, 10710-10720]. The reaction requires NAD as ADP-ribose donor. This work reports on the capacity of an NAD analog, the nicotinamide 1-N6-ethenoadenine dinucleotide (ϵNAD), to be a substrate of diphtheria toxin fragment A in the transferring reaction of the fluorescent moiety, the ϵADP-ribose, to the EF-2. As a consequence of the transfer of the ϵADP-ribosyl moiety to the EF-2, there is an increase in the emission intensity of the fluorophore and a blue shift in its emission maximum. The ϵADP-ribosylated EF-2, like ADP-ribosylated EF-2, retains the capacity to bind GTP and ribosome. The utility of introducing a fluorescent probe in a well defined point of the EF-2 molecule for conformational or binding studies is discussed

    Stem cell transplantation for ischemic stroke

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    Background Stroke is a leading cause of morbidity and mortality worldwide, with very large healthcare and social costs, and a strong demand for alternative therapeutic approaches. Preclinical studies have shown that stem cells transplanted into the brain can lead to functional improvement. However, to date, evidence for the benefits of stem cell transplantation in people with ischemic stroke is lacking. This is the first update of the Cochrane review published in 2010. Objectives To assess the efficacy and safety of stem cell transplantation compared with control in people with ischemic stroke. Search methods We searched the Cochrane Stroke Group Trials Register (last searched August 2018), CENTRAL (last searched August 2018), MED-LINE (1966 to August 2018), Embase (1980 to August 2018), and BIOSIS (1926 to August 2018). We handsearched potentially relevant conference proceedings, screened reference lists, and searched ongoing trials and research registers (last searched August 2018). We also contacted individuals active in the field and stem cell manufacturers (last contacted August 2018). Selection criteria We included randomized controlled trials (RCTs) that recruited people with ischemic stroke, in any phase of the disease (acute, subacute or chronic), and an ischemic lesion confirmed by computerized tomography or magnetic resonance imaging scan. We included all types of stem cell transplantation, regardless of cell source (autograft, allograft, or xenograft; embryonic, fetal, or adult; from brain or other tissues), route of cell administration (systemic or local), and dosage. The primary outcome was efficacy (assessed as neurologic impairment or functional outcome) at longer term follow-up (minimum six months). Secondary outcomes included post-procedure safety outcomes (death, worsening of neurological deficit, infections, and neoplastic transformation). Data collection and analysis Two review authors independently applied the inclusion criteria, assessed trial quality and risk of bias, and extracted data. If needed, we contacted study authors for additional information. We performed random effects meta-analyses when two or more RCTs were available for any outcome. We assessed the certainty of the evidence by using the GRADE approach. Main results In this updated review, we included seven completed RCTs with 401 participants. All tested adult human non-neural stem cells; cells were transplanted during the acute, subacute, or chronic phase of ischemic stroke; administered intravenously, intra-arterially, intracerebrally, or into the lumbar subarachnoid space. Follow-up ranged from six months to seven years. Efficacy outcomes were measured with the National Institutes of Health Stroke Scale (NIHSS), modified Rankin Scale (mRS), or Barthel Index (BI). Safety outcomes included case fatality, and were measured at the end of the trial. Overall, stem cell transplantation was associated with a better clinical outcome when measured with the NIHSS (mean difference [MD]-1.49, 95% confidence interval [CI]-2.65 to-0.33; five studies, 319 participants; low-certainty evidence), but not with the mRS (MD-0.42, 95% CI-0.86 to 0.02; six studies, 371 participants; very low-certainty evidence), or the BI (MD 14.09, 95% CI-1.94 to 30.13; three studies, 170 participants; very low-certainty evidence). The studies in favor of stem cell transplantation had, on average, a higher risk of bias, and a sample size of 32 or fewer participants. No significant safety concerns associated with stem cell transplantation were raised with respect to death (risk ratio [RR] 0.66, 95% CI 0.39 to 1.14; six studies, participants; low-certainty evidence). We were not able to perform the sensitivity analysis according to the quality of studies, because all of them were at high risk of bias. Authors’ conclusions Overall, in participants with ischemic stroke, stem cell transplantation was associated with a reduced neurological impairment, but not with a better functional outcome. No obvious safety concerns were raised. However, these conclusions came mostly from small RCTs with high risk of bias, and the certainty of the evidence ranged from low to very low. More well-designed trials are needed

    Pharmacological and non-pharmacological interventions for adults with ADHD: Protocol for a systematic review and network meta-analysis

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    Introduction It is unclear how pharmacological and non-pharmacological interventions compare with each other in terms of efficacy and tolerability for core symptoms and additional problems in adults with attention-deficit/hyperactivity disorder (ADHD). We aim to conduct the first network meta-analysis (NMA) comparing pharmacological and non-pharmacological interventions (or their combinations) in adults with ADHD. Methods and analysis We will follow the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement for NMAs. We will search a broad set of electronic databases/registries and contact drug companies and experts in the field to retrieve published and unpublished randomised controlled trials (RCTs) (parallel or cross-over) of medications (either licensed or unlicensed) and any non-pharmacological intervention in adults (≥18 years) with ADHD. Primary outcomes will be: (1) change in severity of ADHD core symptoms, and (2) acceptability (all-cause discontinuation). Secondary outcomes will include tolerability (drop-out due to side effects) and change in the severity of emotional dysregulation, executive dysfunctions and quality of life. The risk of bias in each individual RCT included in the NMA will be assessed using the Cochrane Risk of Bias tool-version 2. We will evaluate the transitivity assumption comparing the distribution of possible effect modifiers across treatment comparisons. We will perform Bayesian NMA for each outcome with random-effects model in OpenBUGS. Pooled estimates of NMA will be obtained using the Markov Chains Monte Carlo method. We will judge the credibility in the evidence derived from the NMA using the CINeMA tool (which includes assessment of publication bias). We will conduct a series of sensitivity analyses to assess the robustness of the findings. Ethics and dissemination As this is the protocol for an aggregate-data level NMA, ethical approval will not be required. Results will be disseminated at national/international conferences and in peer-reviewed journals. PROSPERO registration number CRD42021265576

    Evaluating the quality of evidence from a network meta-analysis

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    Systematic reviews that collate data about the relative effects of multiple interventions via network meta-analysis are highly informative for decision-making purposes. A network meta-analysis provides two types of findings for a specific outcome: the relative treatment effect for all pairwise comparisons, and a ranking of the treatments. It is important to consider the confidence with which these two types of results can enable clinicians, policy makers and patients to make informed decisions. We propose an approach to determining confidence in the output of a network meta-analysis. Our proposed approach is based on methodology developed by the Grading of Recommendations Assessment, Development and Evaluation (GRADE) Working Group for pairwise meta-analyses. The suggested framework for evaluating a network meta-analysis acknowledges (i) the key role of indirect comparisons (ii) the contributions of each piece of direct evidence to the network meta-analysis estimates of effect size; (iii) the importance of the transitivity assumption to the validity of network meta-analysis; and (iv) the possibility of disagreement between direct evidence and indirect evidence. We apply our proposed strategy to a systematic review comparing topical antibiotics without steroids for chronically discharging ears with underlying eardrum perforations. The proposed framework can be used to determine confidence in the results from a network meta-analysis. Judgements about evidence from a network meta-analysis can be different from those made about evidence from pairwise meta-analyses. © 2014 Salanti et al

    Pharmacist interventions to improve hypertension management: protocol for a systematic review of randomised controlled trials

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    INTRODUCTION: Hypertension management remains a major public health challenge in primary care. Innovative interventions to improve blood pressure (BP) control are needed. One approach is through community-based models of care with the involvement of pharmacists and other non-physician healthcare professionals. Our objective is to systematically review the evidence of the impact of pharmacist care alone or in collaboration with other healthcare professionals on BP among hypertensive outpatients compared with usual care. Because these interventions can be complex, with various components, the effect size may differ between the type of interventions. One major focus of our study will be to assess carefully the heterogeneity in the effects of these interventions to identify which ones work best in a given healthcare setting. METHODS AND ANALYSIS: Systematic searches of the Medical Literature Analysis and Retrieval System Online (MEDLINE), Excerpta Medica (Embase) and Central Register of Controlled Trials (CENTRAL) databases will be conducted. Randomised controlled trials assessing the effect of pharmacist interventions on BP among outpatients will be included. Examples for pharmacist interventions are patient education, feedback to physician and medication management. The outcome will be the change in BP or BP at follow-up or BP control. Results will be synthesised descriptively and, if appropriate, will be pooled across studies to perform meta-analyses. If feasible, we will also perform a network meta-analysis to compare interventions that have not been compared directly head-to-head by using indirect evidence. Heterogeneity in the effect will be evaluated through prespecified subgroup and stratified analyses, accounting notably for the type and intensity of interventions, patients' characteristics and healthcare setting. ETHICS AND DISSEMINATION: Ethical approval is not required as the results will be drawn from currently available published literature. Outcomes of the review will be shared through peer-reviewed journal and used for implementation policy. PROSPERO REGISTRATION NUMBER: CRD42021279751

    milk protein and cheese yield in buffalo species

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    Buffalo milk samples differing significantly for cheese yield values were analysed by 2D electrophoresis in order to outline a protein profile, with specific regards to k-casein fractions. Four buffaloes, two of which showing high cheese yield and two with low cheese yield selected from a group of 135 subjects were chosen for the proteomic analyses. Six main spots in 2D gels were recognized as αs1-, αs2-, β- and k-casein, α-lactoalbumin, β-lactoglobulin. The main visible differences in the 2D gels between buffaloes with high vs. low cheese yield were found in the appearance of the four k-casein spots (spots numbers:20, 19, 16, 18) which differ in the number of phosphorilation and glycosilation. The area and the intensity of the four spots were calculated by using Melanie II (Bio-Rad) software. Samples with high cheese yield showed higher value of the by-products: area x intensity of spot 16, correspondent to k-casein with one phosphorilation site, and lower values of spots 19 and 20, of k-casein with more than one phosphorilation site and glycosilated

    Incorporating dose effects in network meta-analysis

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    Systematic reviews with network meta-analysis that ignore potential dose effects could limit the applicability and validity of review findings. This article aims to help content experts (eg, clinicians), methodologists, and statisticians better understand how to incorporate dose effects in network meta-analysis. Three models are described that make different clinical and statistical assumptions about how to model dose effects. This article also illustrates the importance of dose effects in understanding the potential risk of harm in people with dementia from cerebrovascular events associated with atypical antipsychotic drug use (quetiapine, olanzapine, and risperidone) and the potential risk of harm in people with nausea and headache associated with cholinesterase inhibitor use (donepezil, galantamine, and rivastigmine). Finally, important considerations when choosing between different network meta-analysis models incorporating dose effects are discussed
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