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11.
Kendra I. Siler‐Marsiglio Gerry Shaw Marieta B. Heaton 《Developmental neurobiology》2004,59(3):261-271
Pycnogenol® (PYC), a patented combination of bioflavonoids extracted from the bark of French maritime pine (Pinus maritima), scavenges free radicals and promotes cellular health. The protective capacity of PYC against ethanol toxicity of neurons has not previously been explored. The present study demonstrates that in postnatal day 9 (P9) rat cerebellar granule cells the antioxidants vitamin E (VE) and PYC (1) dose dependently block cell death following 400, 800, and 1600 mg/dL ethanol exposure (2) inhibit the ethanol‐induced activation of caspase‐3 in the same model system; and (3) reduce neuronal membrane disruption as assayed by phosphatidylserine translocation to the cell surface. These results suggest that both PYC and VE have the potential to act as therapeutic agents, antagonizing the induction of neuronal cell death by ethanol exposure. © 2004 Wiley Periodicals, Inc. J Neurobiol 59: 261–271, 2004 相似文献
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Magni Olsen Kyrkjeeide Kristian Hassel Kjell Ivar Flatberg A. Jonathan Shaw Narjes Yousefi Hans K. Sten?ien 《PloS one》2016,11(2)
Spore-producing organisms have small dispersal units enabling them to become widespread across continents. However, barriers to gene flow and cryptic speciation may exist. The common, haploid peatmoss Sphagnum magellanicum occurs in both the Northern and Southern hemisphere, and is commonly used as a model in studies of peatland ecology and peatmoss physiology. Even though it will likely act as a rich source in functional genomics studies in years to come, surprisingly little is known about levels of genetic variability and structuring in this species. Here, we assess for the first time how genetic variation in S. magellanicum is spatially structured across its full distribution range (Northern Hemisphere and South America). The morphologically similar species S. alaskense was included for comparison. In total, 195 plants were genotyped at 15 microsatellite loci. Sequences from two plastid loci (trnG and trnL) were obtained from 30 samples. Our results show that S. alaskense and almost all plants of S. magellanicum in the northern Pacific area are diploids and share the same gene pool. Haploid plants occur in South America, Europe, eastern North America, western North America, and southern Asia, and five genetically differentiated groups with different distribution ranges were found. Our results indicate that S. magellanicum consists of several distinct genetic groups, seemingly with little or no gene flow among them. Noteworthy, the geographical separation of diploids and haploids is strikingly similar to patterns found within other haploid Sphagnum species spanning the Northern Hemisphere. Our results confirm a genetic division between the Beringian and the Atlantic that seems to be a general pattern in Sphagnum taxa. The pattern of strong genetic population structuring throughout the distribution range of morphologically similar plants need to be considered in future functional genomic studies of S. magellanicum. 相似文献
14.
C D Shaw 《BMJ (Clinical research ed.)》1980,280(6228):1361-1363
Compared with hospitals, general practice has many handicaps in developing medical audit. This is especially true with regard to defining objectives and outcomes of care. Many methods have been proposed to overcome these problems, and several audit studies that have been published are presented here. Further work should concentrate on evaluating the effectiveness of audit in bringing about change rather than on generating information. 相似文献
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B.K. Shaw 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2000,186(7-8):747-757
Many bird species produce vocalizations which are accompanied by distinctive postural displays, but the neural mechanisms that allow such integrated production of vocal and postural motor patterns are not understood. In the crowing behavior of Japanese quail, a characteristic vocal pattern is accompanied by and coordinated with a postural display that consists of a sequence of rapid, patterned head movements. The purpose of the present study was to investigate the role of a midbrain vocal nucleus, the nucleus intercollicularis, in the production of the acoustic and postural components of crowing in quail. Brief electrical stimuli were applied to the nucleus intercollicularis during spontaneously emitted crows in quail with chronically implanted electrodes, to determine if perturbing neural activity in the nucleus intercollicularis resulted in a disruption of ongoing crowing behavior. The most common effect of such stimuli was a concurrent, premature termination of both the acoustic and head movement components of the crow. These results imply that the nucleus intercollicularis plays a role in the production of both the acoustic and postural components of crowing in quail. 相似文献
18.
Jeffrey Pomerance Richard Johnson Shoba Kagal Philip Brooks Malcolm Margolin Arthur Allen 《The Western journal of medicine》1980,133(4):289-291
Recently, there has been increased interest in the influence of maternal prenatal nutrition on the course and outcome of pregnancy. Evidence has accumulated that a woman''s weight before pregnancy and the weight gained during pregnancy directly affect infant birth weight, incidence of neonatal mortality, and growth and development of the infant during the first year of life. Although recent recommendations for weight gain in pregnancy have been liberalized, a survey of 195 pregnant women who had prenatal visits in both clinic and private offices showed deficiencies in their understanding of the subject. Some 37 percent of women believed they should gain 20 pounds (9 kg) or less during pregnancy. Eight percent admitted to dieting before at least one antenatal visit and 54 percent thought their doctor would not be concerned about too little weight gained during pregnancy. This suggests that many women and some doctors are still ignorant of current concepts of proper nutrition during pregnancy. Apparently, increased lay and professional educational efforts are needed. 相似文献
19.
Deborah Shaw Ian R. Poxton John R.W. Govan 《FEMS immunology and medical microbiology》1995,11(2):99-106
Abstract Burkholderia cepacia has emerged as an important multiresistant pathogen in cystic fibrosis (CF), associated in 20% of colonised patients with a rapid and fatal decline in lung function. Although knowledge of B. cepacia epidemiology has improved, the mechanisms involved in pathogenesis remain obscure. In this study, B. cepacia lipopolysaccharide (LPS) was assessed for endotoxic potential and the capacity to induce tumour necrosis factor (TNF). LPS preparations from clinical and environmental isolates of B. cepacia and from the closely related species Burkholderia gladioli exhibited a higher endotoxic activity and more pronounced cytokine response in vitro compared to preparations from the major CF pathogen Pseudomonas aeruginosa . This study may help to explain the vicious host immune response observed during pulmonary exacerbations in CF patients colonised by B. cepacia and lead to therapeutic advances in clinical management. 相似文献
20.
Olivia Sackett Katherina Petrou Brian Reedy Ross Hill Martina Doblin John Beardall Peter Ralph Philip Heraud 《The ISME journal》2016,10(2):416-426
Diatoms, an important group of phytoplankton, bloom annually in the Southern Ocean, covering thousands of square kilometers and dominating the region''s phytoplankton communities. In their role as the major food source to marine grazers, diatoms supply carbon, nutrients and energy to the Southern Ocean food web. Prevailing environmental conditions influence diatom phenotypic traits (for example, photophysiology, macromolecular composition and morphology), which in turn affect the transfer of energy, carbon and nutrients to grazers and higher trophic levels, as well as oceanic biogeochemical cycles. The paucity of phenotypic data on Southern Ocean phytoplankton limits our understanding of the ecosystem and how it may respond to future environmental change. Here we used a novel approach to create a ‘snapshot'' of cell phenotype. Using mass spectrometry, we measured nitrogen (a proxy for protein), total carbon and carbon-13 enrichment (carbon productivity), then used this data to build spectroscopy-based predictive models. The models were used to provide phenotypic data for samples from a third sample set. Importantly, this approach enabled the first ever rate determination of carbon productivity from a single time point, circumventing the need for time-series measurements. This study showed that Chaetoceros simplex was less productive and had lower protein and carbon content during short-term periods of high salinity. Applying this new phenomics approach to natural phytoplankton samples could provide valuable insight into understanding phytoplankton productivity and function in the marine system. 相似文献