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991.
Previously, a 2D gel electrophoresis approach was developed for the Escherichia coli inner membrane, which detects membrane protein complexes that are stable in sodium dodecyl sulfate (SDS) at room temperature, and dissociate under the influence of trifluoroethanol [R. E. Spelbrink et al., J. Biol. Chem. 280 (2005), 28742-8]. Here, the method was applied to the evolutionarily related mitochondrial inner membrane that was isolated from the yeast Saccharomyces cerevisiae. Surprisingly, only very few proteins were found to be dissociated by trifluoroethanol of which Lpd1p, a component of multiple protein complexes localized in the mitochondrial matrix, is the most prominent. Usage of either milder or more stringent conditions did not yield any additional proteins that were released by fluorinated alcohols. This strongly suggests that membrane protein complexes in yeast are less stable in SDS solution than their E. coli counterparts, which might be due to the overall reduced hydrophobicity of mitochondrial transmembrane proteins. 相似文献
992.
I. Toumi M. Gargouri I. Nouairi P. N. Moschou A. Ben Salem-Fnayou A. Mliki M. Zarrouk A. Ghorbel 《Biologia Plantarum》2008,52(1):161-164
To dissect differences in both lipid accumulation and composition and the role of these modifications during drought stress,
four grapevine cultivars exhibiting differential tolerance to drought were subjected to water shortage. Tolerant cultivars,
Kahli Kerkennah and Cardinal, exhibited higher leaf water potential (Ψw), and lower lipid peroxidation compared to the sensitive cultivars Guelb Sardouk and Superior Seedless during stress. Total
lipid amounts increased during stress only in the leaves of the tolerant cultivars. Drought induced increases in the ratios
digalactosyldiacylglycerol/monogalactosyldiacylglycerol and phosphatidylcholine/phoshatidylethanolamine of almost all the
drought stressed cultivars. Moreover, the overall analysis of the composition of fatty acids revealed that a linolenic acid
was prevalent in grapevine and the unsaturation level of lipids increased under water stress in all the cultivars. Specific
adjustments in the lipid composition during stress could compromise stress tolerance. 相似文献
993.
994.
In previous work, we constructed a simple electro-mechanical model of transduction in the rat mystacial follicle that was
able to replicate primary afferent response profiles to a variety of whisker deflection stimuli. Here, we update that model
to fit newly available spike-timing response data, and demonstrate that the new model produces appropriate responses to richer
stimuli, including pseudo white noise and natural textures, at a spike-timing level of detail. Additionally, we demonstrate
reliable distributed encoding of multi-component oscillatory signals. No modifications were necessary to the mechanical model
of the physical components of the follicle–sinus complex, supporting its generality. We conclude that this model, and its
continued development, will aid the understanding both of somatosensory systems in general, and of physiological results from
higher (e.g. thalamocortical) systems by accurately characterising the signals on which they operate. 相似文献
995.
Bel Hadj Ali I Thys M Beltaief N Schrauwen I Hilgert N Vanderstraeten K Dieltjens N Mnif E Hachicha S Besbes G Ben Arab S Van Camp G 《Human genetics》2008,123(3):267-272
Otosclerosis is a common disorder of the otic capsule resulting in hearing impairment in 0.3–0.4% of the Caucasian population.
The aetiology of the disease remains unclear. In most cases, otosclerosis can be considered as a complex disease. In some
cases, the disease is inherited as an autosomal dominant trait, sometimes with reduced penetrance. To date, seven autosomal
dominant loci have been reported, but none of the disease-causing genes has been identified. In this study, we present the
results of a genome-wide linkage analysis in a large Tunisian family segregating autosomal dominant otosclerosis. Linkage
analysis localised the responsible gene to chromosome 9p13.1-9q21.11 with a maximal LOD score of 4.13, and this locus was
named OTSC8. Using newly generated short tandem repeat polymorphism markers, we mapped this new otosclerosis locus to a 34.16 Mb interval
between the markers D9S970 and D9S1799. This region comprises the pericentromeric region on both arms of chromosome 9, a highly
complex region containing many duplicated sequences.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
996.
Jeltsje S Cnossen Karlijn C Vollebregt Nynke de Vrieze Gerben ter Riet Ben W J Mol Arie Franx Khalid S Khan Joris A M van der Post 《BMJ (Clinical research ed.)》2008,336(7653):1117-1120
Objective To determine the accuracy of using systolic and diastolic blood pressure, mean arterial pressure, and increase of blood pressure to predict pre-eclampsia.Design Systematic review with meta-analysis of data on test accuracy.Data sources Medline, Embase, Cochrane Library, Medion, checking reference lists of included articles and reviews, contact with authors.Review methods Without language restrictions, two reviewers independently selected the articles in which the accuracy of blood pressure measurement during pregnancy was evaluated to predict pre-eclampsia. Data were extracted on study characteristics, quality, and results to construct 2×2 tables. Summary receiver operating characteristic curves and likelihood ratios were generated for the various levels and their thresholds.Results 34 studies, testing 60 599 women (3341 cases of pre-eclampsia), were included. In women at low risk for pre-eclampsia, the areas under the summary receiver operating characteristic curves for blood pressure measurement in the second trimester were 0.68 (95% confidence interval 0.64 to 0.72) for systolic blood pressure, 0.66 (0.59 to 0.72) for diastolic blood pressure, and 0.76 (0.70 to 0.82) for mean arterial pressure. Findings for the first trimester showed a similar pattern. Second trimester mean arterial pressure of 90 mm Hg or more showed a positive likelihood ratio of 3.5 (95% confidence interval 2.0 to 5.0) and a negative likelihood ratio of 0.46 (0.16 to 0.75). In women deemed to be at high risk, a diastolic blood pressure of 75 mm Hg or more at 13 to 20 weeks’ gestation best predicted pre-eclampsia: positive likelihood ratio 2.8 (1.8 to 3.6), negative likelihood ratio 0.39 (0.18 to 0.71). Additional subgroup analyses did not show improved predictive accuracy.Conclusion When blood pressure is measured in the first or second trimester of pregnancy, the mean arterial pressure is a better predictor for pre-eclampsia than systolic blood pressure, diastolic blood pressure, or an increase of blood pressure. 相似文献
997.
血管中白细胞等的粘附、聚集问题能够影响微循环的血流速度,是损伤血管内皮细胞乃至形成血栓的主要因素之一。在内毒素注射大白鼠的随机、对照实验中,发现电磁水能够减轻内毒素所致的炎症刺激,并能够降低白、红细胞和血小板的粘附、聚集,能降低白细胞的渗出,能提高红细胞的电泳率,能抑制血流速度的减慢和能够减轻血管内皮细胞的损伤。t检验,差异显著(P<0.01)以及差异明显(P<0.05)。揭示电磁水能够提高血细胞和血管内皮细胞的表面负电荷密度,并可以减轻外因(如,内毒素)对体内细胞和血管的损伤。说明电磁水能够改善微循环,维系正常血流和防止血栓形成。 相似文献
998.
999.
1000.
Pentoxifylline reduces fibrin deposition and prolongs survival in neonatal hyperoxic lung injury. 总被引:4,自引:0,他引:4
Simone A J ter Horst Gerry T M Wagenaar Eveline de Boer Marg?t A van Gastelen Joost C M Meijers Bart J Biemond Ben J H M Poorthuis Frans J Walther 《Journal of applied physiology》2004,97(5):2014-2019
Bronchopulmonary dysplasia is a leading cause of mortality and morbidity in preterm infants despite improved treatment modalities. Pentoxifylline, a phosphodiesterase inhibitor, inhibits multiple processes that lead to neonatal hyperoxic lung injury, including inflammation, coagulation, and edema. Using a preterm rat model, we investigated the effects of pentoxifylline on hyperoxia-induced lung injury and survival. Preterm rat pups were exposed to 100% oxygen and injected subcutaneously with 0.9% saline or 75 mg/kg pentoxifylline twice a day. On day 10, lung tissue was harvested for histology, fibrin deposition, and mRNA expression, and bronchoalveolar lavage fluid was collected for total protein concentration. Pentoxifylline treatment increased mean survival by 3 days (P = 0.0018) and reduced fibrin deposition by 66% (P < 0.001) in lung homogenates compared with untreated hyperoxia-exposed controls. Monocyte chemoattractant protein-1 expression in lung homogenates was decreased, but the expressions of TNF-alpha, IL-6, matrix metalloproteinase-12, tissue factor, and plasminogen activator inhibitor-1 were similar in both groups. Total protein concentration in bronchoalveolar lavage fluid was decreased by 33% (P = 0.029) in the pentoxifylline group. Pentoxifylline treatment attenuates alveolar fibrin deposition and prolongs survival in preterm rat pups with neonatal hyperoxic lung injury, probably by reducing capillary-alveolar protein leakage. 相似文献