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排序方式: 共有459条查询结果,搜索用时 843 毫秒
141.
Eric D. Horowitz K. Shefaet Rahman Brian D. Bower David J. Dismuke Michael R. Falvo Jack D. Griffith Stephen C. Harvey Aravind Asokan 《Journal of virology》2013,87(6):2994-3002
We describe biophysical and ultrastructural differences in genome release from adeno-associated virus (AAV) capsids packaging wild-type DNA, recombinant single-stranded DNA (ssDNA), or dimeric, self-complementary DNA (scDNA) genomes. Atomic force microscopy and electron microscopy (EM) revealed that AAV particles release packaged genomes and undergo marked changes in capsid morphology upon heating in physiological buffer (pH 7.2). When different AAV capsids packaging ss/scDNA varying in length from 72 to 123% of wild-type DNA (3.4 to 5.8 kb) were incrementally heated, the proportion of uncoated AAV capsids decreased with genome length as observed by EM. Genome release was further characterized by a fluorimetric assay, which demonstrated that acidic pH and high osmotic pressure suppress genome release from AAV particles. In addition, fluorimetric analysis corroborated an inverse correlation between packaged genome length and the temperature needed to induce uncoating. Surprisingly, scAAV vectors required significantly higher temperatures to uncoat than their ssDNA-packaging counterparts. However, externalization of VP1 N termini appears to be unaffected by packaged genome length or self-complementarity. Further analysis by tungsten-shadowing EM revealed striking differences in the morphologies of ssDNA and scDNA genomes upon release from intact capsids. Computational modeling and molecular dynamics simulations suggest that the unusual thermal stability of scAAV vectors might arise from partial base pairing and optimal organization of packaged scDNA. Our work further defines the biophysical mechanisms underlying adeno-associated virus uncoating and genome release. 相似文献
142.
Stoats are significant predators of native fauna in New Zealand. They occur in many habitat types and consume a wide range of prey. The diet of stoats in the Tasman River, South Canterbury, was studied by analysis of scats and den contents. Analysis of 206 scats showed that stoats ate mainly lagomorphs, birds and invertebrates. Minor components included mice, lizards, fish and hedgehogs. Stoats ate more birds in spring than in autumn, and female stoats ate more invertebrates than did males. The contents of 219 dens collected in the same area at the same time provided further information. Birds and lagomorphs occurred at high frequency in dens, and other components were minor. Remains in dens were larger than in scats and allowed identification of many more prey items to species level. Den contents revealed a potentially substantial impact of stoats on threatened shorebirds locally; this impact was not detected by analysis of scats. 相似文献
143.
Holder Peter E. Jeanson Amanda L. Lennox Robert J. Brownscombe Jacob W. Arlinghaus Robert Danylchuk Andy J. Bower Shannon D. Hyder Kieran Hunt Len M. Fenichel Eli P. Venturelli Paul A. Thorstad Eva B. Allen Micheal S. Potts Warren M. Clark-Danylchuk Sascha Claussen Julie E. Lyle Jeremy M. Tsuboi Jun-ichi Brummett Randall Freire Kátia M. F. Tracey Sean R. Skov Christian Cooke Steven J. 《Reviews in Fish Biology and Fisheries》2020,30(1):137-151
Reviews in Fish Biology and Fisheries - Recreational fisheries hold immense ecological, social, and economic value. The management of these fisheries is increasingly important as we move forward in... 相似文献
144.
Lei CZ Zhang CM Weining S Campana MG Bower MA Zhang XM Liu L Lan XY Chen H 《Animal genetics》2011,42(4):432-436
The origins of the domestic water buffalo remain contentious. To better understand the origins of Chinese water buffalo, we sequenced the complete mitochondrial cytochrome b (MT-CYB) gene from 270 individuals representing 13 Chinese domestic swamp buffalo populations. We found genetic evidence of introgression of river buffalo into Chinese swamp buffalo herds. Swamp buffalo haplotypes can be divided into two highly divergent lineages (A and B), suggesting that Chinese native swamp buffalo have two maternal origins. We found that the A→G transition in the buffalo MT-CYB gene stop codon resulted in buffalo haplotypes being terminated by one of two stop codons: AGA or AGG. AGA is common to river buffalo and lineage A of swamp buffalo, while AGG is specific to lineage B of swamp buffalo. Lineage A appears to have been domesticated in China. Further genetic evidence is required to clarify the origins of lineage B. 相似文献
145.
Tom Blakeman Christian Blickem Anne Kennedy David Reeves Peter Bower Hannah Gaffney Caroline Gardner Victoria Lee Praksha Jariwala Shoba Dawson Rahena Mossabir Helen Brooks Gerry Richardson Eldon Spackman Ivaylo Vassilev Carolyn Chew-Graham Anne Rogers 《PloS one》2014,9(10)
Background
Implementation of self-management support in traditional primary care settings has proved difficult, encouraging the development of alternative models which actively link to community resources. Chronic kidney disease (CKD) is a common condition usually diagnosed in the presence of other co-morbidities. This trial aimed to determine the effectiveness of an intervention to provide information and telephone-guided access to community support versus usual care for patients with stage 3 CKD.Methods and Findings
In a pragmatic, two-arm, patient level randomised controlled trial 436 patients with a diagnosis of stage 3 CKD were recruited from 24 general practices in Greater Manchester. Patients were randomised to intervention (215) or usual care (221). Primary outcome measures were health related quality of life (EQ-5D health questionnaire), blood pressure control, and positive and active engagement in life (heiQ) at 6 months. At 6 months, mean health related quality of life was significantly higher for the intervention group (adjusted mean difference = 0.05; 95% CI = 0.01, 0.08) and blood pressure was controlled for a significantly greater proportion of patients in the intervention group (adjusted odds-ratio = 1.85; 95% CI = 1.25, 2.72). Patients did not differ significantly in positive and active engagement in life. The intervention group reported a reduction in costs compared with control.Conclusions
An intervention to provide tailored information and telephone-guided access to community resources was associated with modest but significant improvements in health related quality of life and better maintenance of blood pressure control for patients with stage 3 CKD compared with usual care. However, further research is required to identify the mechanisms of action of the intervention.Trial Registration
Controlled-Trials.com ISRCTN45433299 相似文献146.
Background and Objectives
The Wii Balance Board (WBB) is a globally accessible device that shows promise as a clinically useful balance assessment tool. Although the WBB has been found to be comparable to a laboratory-grade force platform for obtaining centre of pressure data, it has not been comprehensively studied in clinical populations. The aim of this study was to investigate the measurement properties of tests utilising the WBB in people after stroke.Methods
Thirty individuals who were more than three months post-stroke and able to stand unsupported were recruited from a single outpatient rehabilitation facility. Participants performed standardised assessments incorporating the WBB and customised software (static stance with eyes open and closed, static weight-bearing asymmetry, dynamic mediolateral weight shifting and dynamic sit-to-stand) in addition to commonly employed clinical tests (10 Metre Walk Test, Timed Up and Go, Step Test and Functional Reach) on two testing occasions one week apart. Test-retest reliability and construct validity of the WBB tests were investigated.Results
All WBB-based outcomes were found to be highly reliable between testing occasions (ICC = 0.82 to 0.98). Correlations were poor to moderate between WBB variables and clinical tests, with the strongest associations observed between task-related activities, such as WBB mediolateral weight shifting and the Step Test.Conclusions
The WBB, used with customised software, is a reliable and potentially useful tool for the assessment of balance and weight-bearing asymmetry following stroke. Future research is recommended to further investigate validity and responsiveness. 相似文献147.
Andrew P. Morgan James J. Crowley Randal J. Nonneman Corey R. Quackenbush Cheryl N. Miller Allison K. Ryan Molly A. Bogue Sur Herrera Paredes Scott Yourstone Ian M. Carroll Thomas H. Kawula Maureen A. Bower R. Balfour Sartor Patrick F. Sullivan 《PloS one》2014,9(12)
The second-generation antipsychotic olanzapine is effective in reducing psychotic symptoms but can cause extreme weight gain in human patients. We investigated the role of the gut microbiota in this adverse drug effect using a mouse model. First, we used germ-free C57BL/6J mice to demonstrate that gut bacteria are necessary and sufficient for weight gain caused by oral delivery of olanzapine. Second, we surveyed fecal microbiota before, during, and after treatment and found that olanzapine potentiated a shift towards an “obesogenic” bacterial profile. Finally, we demonstrated that olanzapine has antimicrobial activity in vitro against resident enteric bacterial strains. These results collectively provide strong evidence for a mechanism underlying olanzapine-induced weight gain in mouse and a hypothesis for clinical translation in human patients. 相似文献
148.
149.
Cdc42-dependent activation of NADPH oxidase is involved in ethanol-induced neuronal oxidative stress
It has been suggested that excessive reactive oxygen species (ROS) and oxidative stress play an important role in ethanol-induced damage to both the developing and mature central nervous system (CNS). The mechanisms underlying ethanol-induced neuronal ROS, however, remain unclear. In this study, we investigated the role of NADPH oxidase (NOX) in ethanol-induced ROS generation. We demonstrated that ethanol activated NOX and inhibition of NOX reduced ethanol-promoted ROS generation. Ethanol significantly increased the expression of p47(phox) and p67(phox), the essential subunits for NOX activation in cultured neuronal cells and the cerebral cortex of infant mice. Ethanol caused serine phosphorylation and membrane translocation of p47(phox) and p67(phox), which were prerequisites for NOX assembly and activation. Knocking down p47(phox) with the small interfering RNA was sufficient to attenuate ethanol-induced ROS production and ameliorate ethanol-mediated oxidative damage, which is indicated by a decrease in protein oxidation and lipid peroxidation. Ethanol activated cell division cycle 42 (Cdc42) and overexpression of a dominant negative (DN) Cdc42 abrogate ethanol-induced NOX activation and ROS generation. These results suggest that Cdc42-dependent NOX activation mediates ethanol-induced oxidative damages to neurons. 相似文献
150.