Genome editing by Cas9, which cleaves double-stranded DNA at a sequence programmed by a short single-guide RNA (sgRNA), can result in off-target DNA modification that may be detrimental in some ...applications. To improve DNA cleavage specificity, we generated fusions of catalytically inactive Cas9 and FokI nuclease (fCas9). DNA cleavage by fCas9 requires association of two fCas9 monomers that simultaneously bind target sites ∼15 or 25 base pairs apart. In human cells, fCas9 modified target DNA sites with >140-fold higher specificity than wild-type Cas9 and with an efficiency similar to that of paired Cas9 'nickases', recently engineered variants that cleave only one DNA strand per monomer. The specificity of fCas9 was at least fourfold higher than that of paired nickases at loci with highly similar off-target sites. Target sites that conform to the substrate requirements of fCas9 occur on average every 34 bp in the human genome, suggesting the versatility of this approach for highly specific genome-wide editing.
The northeastern United States is a predominately-forested region that, like most of the eastern U.S., has undergone a 400-year history of intense logging, land clearance for agriculture, and natural ...reforestation. This setting affords the opportunity to address a major ecological question: How similar are today's forests to those existing prior to European colonization? Working throughout a nine-state region spanning Maine to Pennsylvania, we assembled a comprehensive database of archival land-survey records describing the forests at the time of European colonization. We compared these records to modern forest inventory data and described: (1) the magnitude and attributes of forest compositional change, (2) the geography of change, and (3) the relationships between change and environmental factors and historical land use. We found that with few exceptions, notably the American chestnut, the same taxa that made up the pre-colonial forest still comprise the forest today, despite ample opportunities for species invasion and loss. Nonetheless, there have been dramatic shifts in the relative abundance of forest taxa. The magnitude of change is spatially clustered at local scales (<125 km) but exhibits little evidence of regional-scale gradients. Compositional change is most strongly associated with the historical extent of agricultural clearing. Throughout the region, there has been a broad ecological shift away from late successional taxa, such as beech and hemlock, in favor of early- and mid-successional taxa, such as red maple and poplar. Additionally, the modern forest composition is more homogeneous and less coupled to local climatic controls.
Most cancers depend on a high rate of aerobic glycolysis for their continued growth and survival. Paradoxically, some cancer cell lines also display addiction to glutamine despite the fact that ...glutamine is a nonessential amino acid that can be synthesized from glucose. The high rate of glutamine uptake exhibited by glutamine-dependent cells does not appear to result solely from its role as a nitrogen donor in nucleotide and amino acid biosynthesis. Instead, glutamine plays a required role in the uptake of essential amino acids and in maintaining activation of TOR (target of rapamycin) kinase. Moreover, in many cancer cells, glutamine is the primary mitochondrial substrate and is required for maintenance of mitochondrial membrane potential and integrity and for support of the NADPH production needed for redox control and macromolecular synthesis.
Although genetic factors contribute to almost half of all cases of deafness, treatment options for genetic deafness are limited. We developed a genome-editing approach to target a dominantly ...inherited form of genetic deafness. Here we show that cationic lipid-mediated in vivo delivery of Cas9-guide RNA complexes can ameliorate hearing loss in a mouse model of human genetic deafness. We designed and validated, both in vitro and in primary fibroblasts, genome editing agents that preferentially disrupt the dominant deafness-associated allele in the Tmc1 (transmembrane channel-like gene family 1) Beethoven (Bth) mouse model, even though the mutant Tmc1
allele differs from the wild-type allele at only a single base pair. Injection of Cas9-guide RNA-lipid complexes targeting the Tmc1
allele into the cochlea of neonatal Tmc1
mice substantially reduced progressive hearing loss. We observed higher hair cell survival rates and lower auditory brainstem response thresholds in injected ears than in uninjected ears or ears injected with control complexes that targeted an unrelated gene. Enhanced acoustic startle responses were observed among injected compared to uninjected Tmc1
mice. These findings suggest that protein-RNA complex delivery of target gene-disrupting agents in vivo is a potential strategy for the treatment of some types of autosomal-dominant hearing loss.
Post-intensive care syndrome: A concept analysis Yuan, Chu; Timmins, Fiona; Thompson, David R
International journal of nursing studies,
February 2021, 2021-Feb, 2021-02-00, 20210201, Letnik:
114
Journal Article
Recenzirano
Odprti dostop
Post-intensive care syndrome is a term used to describe new or worsening multidimensional impairments in physical, psychological cognitive and social status arising from critical illness and ...persisting beyond hospital discharge. It is associated with high morbidity among patients discharged from intensive care units. However, due to its complexities, which encompass physical, psychological, cognitive and social impairments, the exact nature of this condition has not been fully conceptualized. The aim of this analysis therefore was to define the concept of post-intensive care syndrome. This conceptual clarity provides a general definition that is essential for practitioners and researchers to gain a comprehensive understanding of the syndrome and provide for accurate measurement of its incidence and prevalence.
The Walker and Avant approach to concept analysis guided this investigation.
An electronic search of the literature using PubMed, CINHAL, PsycArticles, Academic search complete, Science Direct, MEDLINE and Health Source databases informed the analysis. The search included both quantitative and qualitative studies related to post-intensive care syndrome published in English between 2010 and 2020.
Of the 3948 articles identified, 24 ultimately met the inclusion criteria. Analysis identified the defining attributes of post-intensive care syndrome as: (1) new or worsening multidimensional impairments; (2) physical dysfunction; (3) psychological disorder; (4) cognitive impairment; (5) failed social reconstruction; and (6) persistent impaired multidimensional symptoms extending beyond intensive care and hospital discharge. Antecedents were divided into two categories: pre-existing and those related to the intensive care admission. Consequences were identified as both positive (for example the establishment of coping processes) and adverse (for example decreased quality of life and caregiver burden).
Post-intensive care syndrome affects more than half of patients discharged from intensive care units. This operational definition and conceptual understanding of this syndrome will help improve understanding and inform the design of preventative strategies to improve long-term consequences of the syndrome. Future research and standardized instrument development will serve to better understand the scope and characteristics of this syndrome and inform the development of possible preventative interventions.
Background
Coronary heart disease (CHD) is the single most common cause of death globally. However, with falling CHD mortality rates, an increasing number of people live with CHD and may need support ...to manage their symptoms and prognosis. Exercise‐based cardiac rehabilitation (CR) aims to improve the health and outcomes of people with CHD. This is an update of a Cochrane systematic review previously published in 2011.
Objectives
To assess the effectiveness and cost‐effectiveness of exercise‐based CR (exercise training alone or in combination with psychosocial or educational interventions) compared with usual care on mortality, morbidity and HRQL in patients with CHD.
To explore the potential study level predictors of the effectiveness of exercise‐based CR in patients with CHD.
Search methods
We updated searches from the previous Cochrane review, by searching Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, Issue 6, 2014) from December 2009 to July 2014. We also searched MEDLINE (Ovid), EMBASE (Ovid), CINAHL (EBSCO) and Science Citation Index Expanded (December 2009 to July 2014).
Selection criteria
We included randomised controlled trials (RCTs) of exercise‐based interventions with at least six months’ follow‐up, compared with a no exercise control. The study population comprised men and women of all ages who have had a myocardial infarction (MI), coronary artery bypass graft (CABG) or percutaneous coronary intervention (PCI), or who have angina pectoris, or coronary artery disease. We included RCTs that reported at least one of the following outcomes: mortality, MI, revascularisations, hospitalisations, health‐related quality of life (HRQL), or costs.
Data collection and analysis
Two review authors independently screened all identified references for inclusion based on the above inclusion and exclusion criteria. One author extracted data from the included trials and assessed their risk of bias; a second review author checked data. We stratified meta‐analysis by the duration of follow up of trials, i.e. short‐term: 6 to 12 months, medium‐term: 13 to 36 months, and long‐term: > 3 years.
Main results
This review included 63 trials which randomised 14,486 people with CHD. This latest update identified 16 new trials (3872 participants). The population included predominantly post‐MI and post‐revascularisation patients and the mean age of patients within the trials ranged from 47.5 to 71.0 years. Women accounted for fewer than 15% of the patients recruited. Overall trial reporting was poor, although there was evidence of an improvement in quality of reporting in more recent trials.
As we found no significant difference in the impact of exercise‐based CR on clinical outcomes across follow‐up, we focused on reporting findings pooled across all trials at their longest follow‐up (median 12 months). Exercise‐based CR reduced cardiovascular mortality compared with no exercise control (27 trials; risk ratio (RR) 0.74, 95% CI 0.64 to 0.86). There was no reduction in total mortality with CR (47 trials, RR 0.96, 95% CI 0.88 to 1.04). The overall risk of hospital admissions was reduced with CR (15 trials; RR 0.82, 95% CI 0.70 to 0.96) but there was no significant impact on the risk of MI (36 trials; RR 0.90, 95% CI 0.79 to 1.04), CABG (29 trials; RR 0.96, 95% CI 0.80 to 1.16) or PCI (18 trials; RR 0.85, 95% CI 0.70 to 1.04).
There was little evidence of statistical heterogeneity across trials for all event outcomes, and there was evidence of small study bias for MI and hospitalisation, but no other outcome. Predictors of clinical outcomes were examined across the longest follow‐up of studies using univariate meta‐regression. Results show that benefits in outcomes were independent of participants' CHD case mix (proportion of patients with MI), type of CR (exercise only vs comprehensive rehabilitation) dose of exercise, length of follow‐up, trial publication date, setting (centre vs home‐based), study location (continent), sample size or risk of bias.
Given the heterogeneity in outcome measures and reporting methods, meta‐analysis was not undertaken for HRQL. In five out of 20 trials reporting HRQL using validated measures, there was evidence of significant improvement in most or all of the sub‐scales with exercise‐based CR compared to control at follow‐up. Four trial‐based economic evaluation studies indicated exercise‐based CR to be a potentially cost‐effective use of resources in terms of gain in quality‐adjusted life years.
The quality of the evidence for outcomes reported in the review was rated using the GRADE method. The quality of the evidence varied widely by outcome and ranged from low to moderate.
Authors' conclusions
This updated Cochrane review supports the conclusions of the previous version of this review that, compared with no exercise control, exercise‐based CR reduces the risk of cardiovascular mortality but not total mortality. We saw a significant reduction in the risk of hospitalisation with CR but not in the risk of MI or revascularisation. We identified further evidence supporting improved HRQL with exercise‐based CR. More recent trials were more likely to be well reported and include older and female patients. However, the population studied in this review still consists predominantly of lower risk individuals following MI or revascularisation. Further well conducted RCTs are needed to assess the impact of exercise‐based CR in higher risk CHD groups and also those presenting with stable angina. These trials should include validated HRQL outcome measures, explicitly report clinical event outcomes including mortality and hospital admissions, and assess costs and cost‐effectiveness.
Efficient intracellular delivery of proteins is needed to fully realize the potential of protein therapeutics. Current methods of protein delivery commonly suffer from low tolerance for serum, poor ...endosomal escape and limited in vivo efficacy. Here we report that common cationic lipid nucleic acid transfection reagents can potently deliver proteins that are fused to negatively supercharged proteins, that contain natural anionic domains or that natively bind to anionic nucleic acids. This approach mediates the potent delivery of nM concentrations of Cre recombinase, TALE- and Cas9-based transcription activators, and Cas9:sgRNA nuclease complexes into cultured human cells in media containing 10% serum. Delivery of unmodified Cas9:sgRNA complexes resulted in up to 80% genome modification with substantially higher specificity compared to DNA transfection. This approach also mediated efficient delivery of Cre recombinase and Cas9:sgRNA complexes into the mouse inner ear in vivo, achieving 90% Cre-mediated recombination and 20% Cas9-mediated genome modification in hair cells.
•Meta-analysis of randomised control trails of involving yoga asana versus active control.•Stress related physiological measures assessed.•42 Studies including all populations reviewed.•Yoga reduced ...cortisol, systolic blood pressure, heart rate, heart rate variability.•Yoga reduced fasting blood glucose, cholesterol and low density lipoprotein.
Practices that include yoga asanas and mindfulness-based stress reduction for the management of stress are increasingly popular; however, the neurobiological effects of these practices on stress reactivity are not well understood. Many studies investigating the effects of such practices fail to include an active control group. Given the frequency with which people are selecting such interventions as a form of self-management, it is important to determine their effectiveness. Thus, this review investigates the effects of practices that include yoga asanas, with and without mindfulness-based stress reduction, compared to an active control, on physiological markers of stress.
A systematic review and meta-analysis of randomised controlled trials published in English compared practices that included yoga asanas, with and without mindfulness-based stress reduction, to an active control, on stress-related physiological measures. The review focused on studies that measured physiological parameters such as blood pressure, heart rate, cortisol and peripheral cytokine expression. MEDLINE, AMED, CINAHL, PsycINFO, SocINDEX, PubMed, and Scopus were searched in May 2016 and updated in December 2016. Randomised controlled trials were included if they assessed at least one of the following outcomes: heart rate, blood pressure, heart rate variability, mean arterial pressure, C-reactive protein, interleukins or cortisol. Risk of bias assessments included sequence generation, allocation concealment, blinding of assessors, incomplete outcome data, selective outcome reporting and other sources of bias. Meta-analysis was undertaken using Comprehensive Meta-Analysis Software Version 3. Sensitivity analyses were performed using ‘one-study-removed’ analysis. Subgroup analysis was conducted for different yoga and control group types, including mindfulness-based stress reduction versus non-mindfulness-based stress reduction based interventions, different populations, length of intervention, and method of data analysis. A random-effects model was used in all analyses.
Forty two studies were included in the meta-analysis. Interventions that included yoga asanas were associated with reduced evening cortisol, waking cortisol, ambulatory systolic blood pressure, resting heart rate, high frequency heart rate variability, fasting blood glucose, cholesterol and low density lipoprotein, compared to active control. However, the reported interventions were heterogeneous.
Practices that include yoga asanas appear to be associated with improved regulation of the sympathetic nervous system and hypothalamic-pituitary-adrenal system in various populations.
Although recommended in guidelines for the management of coronary heart disease (CHD), concerns have been raised about the applicability of evidence from existing meta-analyses of exercise-based ...cardiac rehabilitation (CR).
The goal of this study is to update the Cochrane systematic review and meta-analysis of exercise-based CR for CHD.
The Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, CINAHL, and Science Citation Index Expanded were searched to July 2014. Retrieved papers, systematic reviews, and trial registries were hand-searched. We included randomized controlled trials with at least 6 months of follow-up, comparing CR to no-exercise controls following myocardial infarction or revascularization, or with a diagnosis of angina pectoris or CHD defined by angiography. Two authors screened titles for inclusion, extracted data, and assessed risk of bias. Studies were pooled using random effects meta-analysis, and stratified analyses were undertaken to examine potential treatment effect modifiers.
A total of 63 studies with 14,486 participants with median follow-up of 12 months were included. Overall, CR led to a reduction in cardiovascular mortality (relative risk: 0.74; 95% confidence interval: 0.64 to 0.86) and the risk of hospital admissions (relative risk: 0.82; 95% confidence interval: 0.70 to 0.96). There was no significant effect on total mortality, myocardial infarction, or revascularization. The majority of studies (14 of 20) showed higher levels of health-related quality of life in 1 or more domains following exercise-based CR compared with control subjects.
This study confirms that exercise-based CR reduces cardiovascular mortality and provides important data showing reductions in hospital admissions and improvements in quality of life. These benefits appear to be consistent across patients and intervention types and were independent of study quality, setting, and publication date.
Rapid reviews: the pros and cons of an accelerated review process Moons, Philip; Goossens, Eva; Thompson, David R
European journal of cardiovascular nursing : journal of the Working Group on Cardiovascular Nursing of the European Society of Cardiology,
06/2021, Letnik:
20, Številka:
5
Journal Article
Recenzirano
Odprti dostop
Although systematic reviews are the method of choice to synthesize scientific evidence, they can take years to complete and publish. Clinicians, managers, and policy-makers often need input from ...scientific evidence in a more timely and resource-efficient manner. For this purpose, rapid reviews are conducted. Rapid reviews are performed using an accelerated process. However, they should not be less systematic than standard systematic reviews, and the introduction of bias must be avoided. In this article, we describe what rapid reviews are, present their characteristics, give some examples, highlight potential pitfalls, and draw attention to the importance of evidence summaries in order to facilitate adoption in clinical decision-making.
PDF
