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排序方式: 共有1032条查询结果,搜索用时 406 毫秒
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Sanjeev Rajakulendran Robert D. S. Pitceathly Jan-Willem Taanman Harry Costello Mary G. Sweeney Cathy E. Woodward Zane Jaunmuktane Janice L. Holton Thomas S. Jacques Brian N. Harding Carl Fratter Michael G. Hanna Shamima Rahman 《PloS one》2016,11(1)
Mutations in the nuclear gene POLG (encoding the catalytic subunit of DNA polymerase gamma) are an important cause of mitochondrial disease. The most common POLG mutation, A467T, appears to exhibit considerable phenotypic heterogeneity. The mechanism by which this single genetic defect results in such clinical diversity remains unclear. In this study we evaluate the clinical, neuropathological and mitochondrial genetic features of four unrelated patients with homozygous A467T mutations. One patient presented with the severe and lethal Alpers-Huttenlocher syndrome, which was confirmed on neuropathology, and was found to have a depletion of mitochondrial DNA (mtDNA). Of the remaining three patients, one presented with mitochondrial encephalomyopathy, lactic acidosis and stroke-like episodes (MELAS), one with a phenotype in the Myoclonic Epilepsy, Myopathy and Sensory Ataxia (MEMSA) spectrum and one with Sensory Ataxic Neuropathy, Dysarthria and Ophthalmoplegia (SANDO). All three had secondary accumulation of multiple mtDNA deletions. Complete sequence analysis of muscle mtDNA using the MitoChip resequencing chip in all four cases demonstrated significant variation in mtDNA, including a pathogenic MT-ND5 mutation in one patient. These data highlight the variable and overlapping clinical and neuropathological phenotypes and downstream molecular defects caused by the A467T mutation, which may result from factors such as the mtDNA genetic background, nuclear genetic modifiers and environmental stressors. 相似文献
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Investigation and modeling of the effects of light spectrum and incident angle on the growth of Chlorella vulgaris in photobioreactors 下载免费PDF全文
Antoine Souliès Jack Legrand Hélène Marec Jérémy Pruvost Cathy Castelain Teodor Burghelea Jean‐François Cornet 《Biotechnology progress》2016,32(2):247-261
An in‐depth investigation of how various illumination conditions influence microalgal growth in photobioreactors (PBR) has been presented. Effects of both the light emission spectrum (white and red) and the light incident angle (0° and 60°) on the PBR surface were investigated. The experiments were conducted in two fully controlled lab‐scale PBRs, a torus PBR and a thin flat‐panel PBR for high cell density culture. The results obtained in the torus PBR were used to build the kinetic growth model of Chlorella vulgaris taken as a model species. The PBR model was then applied to the thin flat‐panel PBR, which was run with various illumination conditions. Its detailed representation of local rate of photon absorption under various conditions (spectral calculation of light attenuation, incident angle influence) enabled the model to take into account all the tested conditions with no further adjustment. This allowed a detailed investigation of the coupling between radiation field and photosynthetic growth. Effects of all the radiation conditions together with pigment acclimation, which was found to be relevant, were investigated in depth. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:247–261, 2016 相似文献
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Agarwal-Mawal A Murray CM Belkhode S Cheema SK 《Canadian journal of physiology and pharmacology》2007,85(3-4):430-438
We investigated whether expression of cholesterol ester transfer protein (CETP) in mice alters the regulation of cholesterol metabolism. Transgenic mice expressing human CETP (CETP-TG) and nontransgenic littermates (non-TG) were fed either a monounsaturated fatty acid (MUFA) or a saturated fatty acid (SFA)-rich diet in the presence or absence of cholesterol. Mice fed with MUFA diet had higher CETP activity compared with SFA-fed mice. Addition of cholesterol to the MUFA diet decreased CETP activity, whereas addition of cholesterol to the SFA diet had no effect. Cholesterol 7alpha-hydroxylase (Cyp7a) activity was higher in CETP-TG mice compared with non-TG mice when fed a MUFA diet, whereas SFA fed CETP-TG mice showed lower Cyp7a activity as compared with non-TG. Microsomal triglyceride transfer protein (MTTP) activity was higher in CETP-TG mice compared with non-TG mice when fed a MUFA diet. HMG-CoA reductase activity was lower in CETP-TG mice compared with non-TG mice when fed a MUFA or a SFA diet. These data demonstrate that the regulation of Cyp7a, HMG-CoA reductase, and MTTP is altered in CETP-TG mice as compared with non-TG mice and these alterations are further modulated by the quality of dietary fats. These findings highlight the importance of CETP in regulating cholesterol homeostasis. 相似文献
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Mond JM Rodgers B Hay PJ Darby A Owen C Baune BT Kennedy RL 《Obesity (Silver Spring, Md.)》2007,15(11):2769-2779
Objective: The objective was to test the hypothesis that, in women, the association between obesity and impairment in psychosocial functioning is mediated by levels of weight and shape concerns and/or binge‐eating frequency. Research Methods and Procedures: Self‐report measures of eating disorder psychopathology, mental health functioning, subjective quality of life in the psychological and social domains, and days “out‐of‐role” associated with any (physical or mental) health problem, were completed by a community sample of women classified as obese (BMI ≥30 kg/m2, n = 639) or non‐obese (BMI <30 kg/m2, n = 4253). For each of the dependent measures, regression models were used to test the hypothesis of mediation by comparing the strength of the relationship between independent and dependent variables with and without inclusion of the putative mediator in the regression model. Results: On each measure, the conditions for perfect mediation were satisfied when weight or shape concerns acted as the putative mediator, indicating that there was no association between obesity and functional impairment after controlling for weight or shape concerns. In contrast, associations between obesity and impairment in psychosocial functioning remained highly significant when binge‐eating frequency was the putative mediator. Discussion: The findings suggest that in women, weight and shape concerns are an important mediator of the relationship between obesity and impairment in psychosocial functioning, whereas binge eating may not be of primary importance. A greater focus on body acceptance in obesity treatment may be indicated. 相似文献
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Sophie O. Vanwambeke Eric F. Lambin Markus P. Eichhorn Stéphane P. Flasse Ralph E. Harbach Linda Oskam Pradya Somboon Stella van Beers Birgit H. B. van Benthem Cathy Walton Roger K. Butlin 《EcoHealth》2007,4(1):37-51
Land-use change, a major constituent of global environmental change, potentially has significant consequences for human health
in relation to mosquito-borne diseases. Land-use change can influence mosquito habitat, and therefore the distribution and
abundance of vectors, and land use mediates human–mosquito interactions, including biting rate. Based on a conceptual model
linking the landscape, people, and mosquitoes, this interdisciplinary study focused on the impacts of changes in land use
on dengue and malaria vectors and dengue transmission in northern Thailand. Extensive data on mosquito presence and abundance,
land-use change, and infection risk determinants were collected over 3 years. The results of the different components of the
study were then integrated through a set of equations linking land use to disease via mosquito abundance. The impacts of a
number of plausible scenarios for future land-use changes in the region, and of concomitant behavioral change were assessed.
Results indicated that land-use changes have a detectable impact on mosquito populations and on infection. This impact varies
according to the local environment but can be counteracted by adoption of preventive measures. 相似文献
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Schwarzenbacher R Jaroszewski L von Delft F Abdubek P Ambing E Biorac T Brinen LS Canaves JM Cambell J Chiu HJ Dai X Deacon AM DiDonato M Elsliger MA Eshagi S Floyd R Godzik A Grittini C Grzechnik SK Hampton E Karlak C Klock HE Koesema E Kovarik JS Kreusch A Kuhn P Lesley SA Levin I McMullan D McPhillips TM Miller MD Morse A Moy K Ouyang J Page R Quijano K Robb A Spraggon G Stevens RC van den Bedem H Velasquez J Vincent J Wang X West B Wolf G Xu Q Hodgson KO Wooley J Wilson IA 《Proteins》2004,55(3):759-763