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151.
Biology Bulletin - This study investigated the protective effects of quercetin (QUE) in doxorubicin (DOX)-induced testicular toxicity in rats. In the present study, testicular histomorphometry, the... 相似文献
152.
Říčan Oldřich Říčanová Štěpánka Dragová Klára Piálek Lubomír Almirón Adriana Casciotta Jorge 《Hydrobiologia》2019,832(1):331-354
Hydrobiologia - We address the diversity of two species groups of the cichlid genus Gymnogeophagus in the Middle Paraná basin using molecular phylogeography and traditional morphological... 相似文献
153.
Gül Şimşek Richard D. Vaughan-Jones Pawel Swietach H. Burak Kandilci 《Journal of cellular physiology》2019,234(4):4681-4694
The heart is highly active metabolically but relatively underperfused and, therefore, vulnerable to ischemia. In addition to acidosis, a key component of ischemia is hypoxia that can modulate gene expression and protein function as part of an adaptive or even maladaptive response. Here, using cardiac-derived HL-1 cells, we investigate the effect of various hypoxic stimuli on the expression and activity of Na+/H + exchanger 1 (NHE1), a principal regulator of intracellular pH. Acute (10 min) anoxia produced a reversible decrease in the sarcolemmal NHE1 activity attributable to NHE1 internalization. Treatment with either 1% O 2 or dimethyloxaloylglycine (DMOG; 1 mM) for 48-hr stabilized hypoxia-inducible factor 1 and reduced the sarcolemmal NHE1 activity by internalization, but without a change in total NHE1 immunoreactivity or message levels of the coding gene ( SLC9A1) determined in whole-cell lysates. Unlike the effect of DMOG, which was rapidly reversed on washout, reoxygenation after a prolonged period of hypoxia did not reverse the effects on NHE1, unless media were also supplemented with a membrane-permeant derivative of glutathione (GSH). Without a prior hypoxic episode, GSH supplementation had no effect on the NHE1 activity. Thus, posthypoxic NHE1 reinsertion can only take place if cells have a sufficient reservoir of a reducing agent. We propose that oxidative stress under prolonged hypoxia depletes intracellular GSH to an extent that curtails NHE1 reinsertion once the hypoxic stimulus is withdrawn. This effect may be cardioprotective, as rapid postischaemic restoration of the NHE1 activity is known to trigger reperfusion injury by producing an intracellular Na +-overload, which is proarrhythmogenic. 相似文献
154.
Aldi T. Kraja Chunyu Liu Jessica L. Fetterman Mariaelisa Graff Christian Theil Have Charles Gu Lisa R. Yanek Mary F. Feitosa Dan E. Arking Daniel I. Chasman Kristin Young Symen Ligthart W. David Hill Stefan Weiss Jian’an Luan Franco Giulianini Ruifang Li-Gao Fernando P. Hartwig Kari E. North 《American journal of human genetics》2019,104(1):112-138
155.
Ale Vanura Tomá ezanka Jaroslav Marlálek Karel Melzoch Gabriela Basaová Vladimir Kian 《FEMS microbiology letters》1988,49(3):411-415
Abstract In Streptomyces fradiae l -threonine is catabolized by threonine dehydratase or threonine aldolase to 2-ketobutyrate or acetaldehyde and glycine, respectively. Threonine dehydratase synthesis is repressed and its activity is inhibited by NH4 + ions. Threonine aldolase is not repressed by NH4 + ions and its activity is slightly stimulated by these ions. The addition of threonine to the medium increased pronouncedly the fraction of non-branched fatty acids with an even carbon number under conditions when threonine dehydratase was repressed and inhibited. The results indicate that threonine serves as a source of propionyl-CoA and 2-methylbutyryl-CoA and also of acetyl-CoA required for tylosin and fatty acid biosynthesis. 相似文献
156.
157.
Assessment of DNA strand breakage by comet assay in diabetic patients and the role of antioxidant supplementation 总被引:7,自引:0,他引:7
Diabetes patients often show increased production of reactive oxidative species (ROS) together with vascular complications. The presence of these ROS may lead to increased DNA damage in peripheral blood lymphocytes that may be revealed by the comet assay. To test whether DNA is damaged in diabetes, peripheral blood samples were taken from 30 control individuals and 63 diabetic patients (15 insulin dependent (IDDM) and 48 non-insulin dependent (NIDDM)) and the alkaline comet assay was used to evaluate background levels of DNA damage. Significant differences were detected between control and diabetic patients in terms of frequencies of damaged cells. The extend of DNA migration was greater in NIDDM patients by comparison with IDDM patients which might indicate that IDDM patients are handling more oxidative damage on a regular basis. Smoker individuals had higher frequencies of cells with migration by comparison with the non-smokers in both groups. Also, clear differences between patients on placebo and on Vitamin E supplementation for 12 weeks were observed on the basis of the extend of DNA migration during single cell gel electrophoresis. 相似文献
158.
Akdemir ZS Tatli II Saracoğlu I Ismailoğlu UB Sahin-Erdemli I Caliş I 《Phytochemistry》2001,56(2):189-193
Two new polyphenolic compounds, myricetin 3-O-(2"-O-galloyl)-beta-D-glucopyranoside and (-)-6-chloroepicatechin, were isolated from the aerial parts of Geranium pratense subsp. finitimum (Woronow) Knuth, along with three known polyphenolic compounds [quercetin 3-O-(2"-O-galloyl)-beta-D-glucopyranoside, quercetin 3-O-(2"-O-galloyl)-beta-D-galactopyranoside, methyl gallate] and tryptophan. Quercetin 3-O-beta-D-glucopyranoside, quercetin 3-O-beta-D-galactopyranoside, quercetin 3-O-(2"-O-galloyl)-beta-D-glucopyranoside and quercetin 3-O-(2"-O-galloyl)-beta-D-galactopyranoside were found to be effective against free radical induced impairment of endothelium-dependent relaxation in isolated rat aorta. 相似文献
159.
160.
Durmaz R Deliorman S Işiksoy S Uyar R Tel E 《Archives of physiology and biochemistry》1999,107(4):286-291
The fact that meningioma shows at least a 2:1 predilection for women over men is considered to be due to endocrinological and paracrine regulation of the development of this tumour. The presence of receptors for the luteinizing hormone releasing hormone (LHRH) in gynaecological cancer permits the use of LHRH agonistic or antagonistic analogues with a direct effect or by the gonado-pituitary axis suppression in the treatment of these tumours. Therefore, the effect of LHRH on meningioma cells is tested in this study. Meningioma cells from three female patients were cultured and LHRH (50 ng/ml) was added to the growth medium daily, for fourteen days. At the end of this period the cells were counted by means of a Coulter Counter. The stimulating effects of LHRH on the increase of the amount of cells in the meningioma monolayer culture were 146% (p < 0.01), 134% (p < 0.05) and 141% (p < 0.05) of the control, respectively, for the three patients. 相似文献