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Carnosine and vitamin E – a promising pair in the combat against testicular oxidative stress in aged rats 下载免费PDF全文
A. F. Aydın J. Çoban I. Doğan‐Ekici S. Doğru‐Abbasoğlu M. Uysal N. Koçak‐Toker 《Andrologia》2015,47(10):1131-1138
Oxidative stress is considered to play a key role in ageing. Carnosine alone or together with vitamin E may prove to be helpful in dealing with problems of ageing through its antioxidant activity. Testis, by producing steroids and possessing a poor antioxidant system may become a strong target for the chronic oxidative stress generated during ageing. Therefore we investigated the in vivo effect of carnosine alone or together with vitamin E on testicular oxidative stress in aged rats. In this study, young (5 months) and aged (22 months) Wistar rats were used. Carnosine (250 mg kg?1; i.p.; 5 days per week) and vitamin E (200 mg kg?1; i.m.; twice per week) were given to aged rats for 2 months. Increased testicular lipid peroxidation and superoxide dismutase activity in aged rats were declined to the levels of young ones by both treatments. Decreased glutathione peroxidase and glutathione transferase activities returned to the level of young's only by carnosine plus vitamin E treatment. Histopathological evaluation described by Johnsen's score, also showed significant improvement with preserved spermatogenesis. Carnosine plus vitamin E treatment appears to stage a powerful performance by attenuating testicular oxidative stress and sparing the antioxidant system. 相似文献
33.
Yavuz Poyrazoglu Turgut Topal Filiz Sezen Bircan Kemal Simsek Ercan Gocgeldi 《Journal of investigative surgery》2015,28(4):188-195
Aim: The purpose of this study was to evaluate the effects of hyperbaric oxygen (HBO) and HBO preconditioning (pre-HBO) on experimental wound healing and tensile strength in the colonic anastomosis of rats. Materials and Methods: A total of 21 Sprague–Dawley rats were divided into three random groups of equal numbers: sham operation, pre-HBO, and HBO. Sham group was given standard left colon resection and end-to-end anastomosis; pre-HBO group received HBO as one dose + colonic resection + anastomosis; HBO group was given colonic resection + anastomosis + HBO. HBO was administrated at 24-hr intervals and relaparatomy was performed on the fifth day. Malondialdehyde (MDA), myeloperoxidase (MPO), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), interleukin (IL)-10, IL-6, tumor necrosis factor-alpha (TNF-α), and hydroxy (OH)-proline levels and anastomotic burst pressure were evaluated. Results: Burst pressure and OH-proline levels markedly increased in the HBO group compared with the sham and pre-HBO groups. When compared with the sham group, MDA and MPO levels were significantly decreased in the HBO and pre-HBO groups. In contrast to these findings, SOD and GSH-Px levels were increased in the HBO group as compared with the sham and pre-HBO groups. TNF-α, IL-6, and IL-10 values were detected at low levels in the HBO group as compared with other groups. Conclusions: HBO administration accelerated wound healing and strengthened the anastomotic tissue. In the light of these results, the HBO administration has beneficial effects and contributed to wound healing in colonic anastomosis. But, as expected, pre-HBO did not alter the results significantly. 相似文献
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Yavuzgil O Ozerkan F Gurgun C Zoghi M Can L Akin M 《Texas Heart Institute journal / from the Texas Heart Institute of St. Luke's Episcopal Hospital, Texas Children's Hospital》2002,29(1):48-50
Thromboembolism is still one of the most important complications of prosthetic heart valves. Embolism to a major coronary branch is rare, but acute proximal occlusions can be fatal, even when the coronary arteries are otherwise normal and intervention is rapid. We report a fatal complication of an exercise test in a patient who had a St. Jude bileaflet mitral valve. After an exercise test, a 42-year-old woman with a mechanical prosthetic valve had a severe hemodynamic collapse with acute ST segment changes. Coronary angiography showed a totally occluded left main coronary artery with TIMI grade 0 to 1 flow. Rapid injection of contrast material and the passage of a floppy guidewire through the thrombus restored a TIMI grade 3 flow. Angiography showed no coronary atherosclerostic involvement. Despite successful coronary reperfusion, intra-aortic balloon counterpulsation, and intensive medication, the patient died. This case demonstrates that exercise testing should be applied with great caution in patients with prosthetic valves, and only after a careful evaluation of valve function. We recommend transesophageal echocardiography prior to exercise testing in these patients. 相似文献
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Gülcan Seymen Karabulut Müge Atar Filiz Mine izmeciolu Jones ükrü Hatun 《Journal of clinical research in pediatric endocrinology》2020,12(4):377
Objective:Premature thelarche (PT) is defined as isolated breast development in girls before eight years of age. Gonadotropin-releasing hormone (GnRH) stimulation test is sometimes used to distinguish between PT and central precocious puberty (CPP), although the interpretation of the test at early ages is challenging. The objective of this study was to determine the follicle stimulating hormone (FSH) and luteinizing hormone (LH) responses to GnRH stimulation in girls with PT below 3 years of age.Methods:A standardized GnRH stimulation test, bone age and pelvic ultrasound were evaluated and those without pubertal progression after a minimum of one-year follow up were included in the study.Results:On GnRH stimulation test, the median (range) baseline LH was 0.29 (0.10-0.74) IU/L, baseline FSH was 4.96 (3.18-7.05) mIU/mL, and the peak median LH was 5.75 (3.31-8.58) IU/L with the peak mean±standard deviation FSH was 40.38±20.37 mIU/mL. Among the patients, 33.3% (n=10) had baseline LH >0.3 IU/L, 67% (n=20) had peak LH >5 IU/l and 16.6% (n=5) >10 IU/L. The mean peak LH/FSH ratio was 0.17±0.09 and was ≤0.43 in all participants.Conclusion:Although consensus statements usually define baseline LH >0.3-0.5 IU/L, peak LH >5 IU/L, and LH/FSH ratios >0.66-1.0 as diagnostic cut-offs for CPP, in children below 3 years of age, the baseline and peak LH values may be similar to pubertal values, possibly due to mini-puberty. A dominant FSH response on GnRH stimulation test is more valuable than the peak LH response in the diagnosis of PT. 相似文献
38.
Pınar Erkekoglu Naciye D. Zeybek Belma K. Giray Walid Rachidi Murat Kızılgün Isabelle Hininger‐Favier Alain Favier Esin Asan Filiz Hincal 《International journal of experimental pathology》2014,95(1):64-77
This study was performed to determine the hepatotoxicity of di(2‐ethylhexyl)phthalate (DEHP) in relation to selenium status. In 3‐week‐old Sprague‐Dawley rats, selenium deficiency was induced by a ≤0.05 selenium mg/kg. A selenium supplementation group was given 1 mg selenium/kg diet for 5 weeks. Di(2‐ethylhexyl)phthalate‐treated groups received 1000 mg/kg dose by gavage during the last 10 days of the experiment. Histopathology, peroxisome proliferation, catalase (CAT) immunoreactivity and activity and apoptosis were assessed. Activities of antioxidant selenoenzymes [glutathione peroxidase 1 (GPx1), glutathione peroxidase 4 (GPx4), thioredoxin reductase (TrxR1)], superoxide dismutase (SOD), and glutathione S‐transferase (GST); aminotransferase, total glutathione (tGSH), and lipid peroxidation (LP) levels were measured. Di(2‐ethylhexyl)phthalate caused cellular disorganization while necrosis and inflammatory cell infiltration were observed in Se‐deficient DEHP group (DEHP/SeD). Catalase activity and immunoreactivity were increased in all DEHP‐treated groups. Glutathione peroxidase 1 and GPx4 activities decreased significantly in DEHP and DEHP/SeD groups, while GST activities decreased in all DEHP‐exposed groups. Thioredoxin reductase activity increased in DEHP and DEHP/SeS, while total SOD activities increased in all DEHP‐treated groups. Lipid peroxidation levels increased significantly in SeD (26%), DEHP (38%) and DEHP/SeD (71%) groups. Selenium supplementation partially ameliorated DEHP‐induced hepatotoxicity; while in DEHP/SeD group, drastic changes in hepatic histopathology and oxidative stress parameters were observed. 相似文献
39.
Ismail Ustunel Nuray Acar Burcu Gemici Ozlem Ozbey Imren Edizer Hakan Soylu Filiz Tepekoy Vecihe Nimet Izgut-Uysal 《Acta histochemica》2014
Apelin has been identified as an endogenous ligand of the orphan G-protein-coupled apelin receptor (APJR). These receptors are widely expressed in the central nervous system and periphery and play a role in the regulation of fluid and glucose homeostasis, feeding behavior, vessel formation, cell proliferation and immunity. We aimed to investigate whether water immersion and restraint stress have effects on apelin and APJR expression and apoptosis in heart tissue of male Wistar rats. The cardiac tissues were obtained from control, water immersion and restraint stress (WIRS) and apelin antagonist (F13A) + WIRS groups of rats and embedded in paraffin wax. Immunohistochemical staining methods were used to localize apelin, APJR and TUNEL immunopositive cells. H-SCORE was used for semi-quantitative determinations. Apelin protein levels were determined by Western blot in the cardiac tissues and plasma corticosteroid levels were measured by enzyme immunoassay (EIA). Apelin immunolocalization was found especially in endothelial cells and mast cells and faintly in cardiomyocytes, APJR immunostaining was shown in endothelial cells and cardiomyocytes, and TUNEL reaction was observed in endothelial cells and in some fibroblasts. Apelin expression was significantly increased in the WIRS and F13A + WIRS groups compared to the control group. The APJR reaction was similar in all groups. The number of TUNEL-positive cells was significantly higher in the F13A + WIRS group than that of the control group. Our study showed that WIRS for 6 h increased plasma corticosterone levels and cardiac apelin expression in rats. The increased levels of apelin inhibited stress-induced apoptosis in heart. These results may be important for the therapeutic approach to a variety of stress-related heart disease. 相似文献
40.
Gabriela E Jones Pia Ostergaard Anthony T Moore Fiona C Connell Denise Williams Oliver Quarrell Angela F Brady Isabel Spier Filiz Hazan Oana Moldovan Dagmar Wieczorek Barbara Mikat Florence Petit Christine Coubes Robert A Saul Glen Brice Kristiana Gordon Steve Jeffery Peter S Mortimer Pradeep C Vasudevan Sahar Mansour 《European journal of human genetics : EJHG》2014,22(7):881-887
Microcephaly with or without chorioretinopathy, lymphoedema, or mental retardation (MCLMR) (MIM No.152950) is a rare autosomal dominant condition for which a causative gene has recently been identified. Mutations in the kinesin family member 11 (KIF11) gene have now been described in 16 families worldwide. This is a review of the condition based on the clinical features of 37 individuals from 22 families. This report includes nine previously unreported families and additional information for some of those reported previously. The condition arose de novo in 8/20 families (40%). The parental results were not available for two probands. The mutations were varied and include missense, nonsense, frameshift, and splice site and are distributed evenly throughout the KIF11 gene. In our cohort, 86% had microcephaly, 78% had an ocular abnormality consistent with the diagnosis, 46% had lymphoedema, 73% had mild-moderate learning difficulties, 8% had epilepsy, and 8% had a cardiac anomaly. We identified three individuals with KIF11 mutations but no clinical features of MCLMR demonstrating reduced penetrance. The variable expression of the phenotype and the presence of mildly affected individuals indicates that the prevalence may be higher than expected, and we would therefore recommend a low threshold for genetic testing. 相似文献