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Effect of dietary selenium and vitamin E on the biomechanical properties of rabbit bones 总被引:1,自引:0,他引:1
Summary It is generally agreed that combined deficiency of selenium and vitamin E leads to several abnormalities including Kashin-Beck disease which is an endemic and chronic degenerative osteoarthrosis. The abnormalities can be reversed by the administration of various forms of selenium and vitamin E.The present study was designed to investigate the effects of dietary selenium and vitamin E on bone tissue and on the biomechanical properties of bone. Young rabbits of both sexes were fed with either a selenium- and vitamin E-adequate diet (control group), or a selenium- and vitamin E-deficient diet or a selenium-excess diet. The selenium-deficient diet resulted in a significant decrease in plasma selenium level and the selenium-excess diet resulted in a significant increase in the plasma selenium level with respect to the corresponding control values (p<0.05). The diets did not affect the blood cell counts considerably but erythrocyte glutathione peroxidase activity increased (decreased) relatively when the plasma selenium level increased (decreased) (p<0.05). The light microscopic investigations of the bone tissues of the two experimental groups indicate that the findings of the present work are compatible with osteomalacia. The biomechanical properties of the bones from the three groups were determined experimentally with bending tests. Both the Se-and vitamin E-deficient diet and the Se-excess diet decreased the biomechanical strength of the bones significantly while the bones belonging to the control group always had the largest modulus of elasticity (p<0.05). 相似文献
3.
Selenium improves cardiac function by attenuating the activation of NF-kappaB due to ischemia-reperfusion injury 总被引:1,自引:0,他引:1
Turan B Saini HK Zhang M Prajapati D Elimban V Dhalla NS 《Antioxidants & redox signaling》2005,7(9-10):1388-1397
Although selenium, an essential trace element and a component of glutathione peroxidase, is known to protect the heart from ischemia-reperfusion (I/R)-induced injury, the mechanisms of this protection are not fully understood. For this purpose, isolated rat hearts were subjected to 30 min of global ischemia followed by 30 min of reperfusion; sodium selenite (25-1,000 nM) was added in the perfusion medium 10 min prior to ischemia, as well as during reperfusion. Selenium caused a dose-dependent improvement in cardiac performance and attenuated the decrease in the ratio of reduced glutathione to oxidized glutathione, as well as the increased level of malondialdehyde in I/R heart. Elevated ratios of nuclear factor-kappaB (NF-kappaB) in particulate and cytosolic fraction and of phosphorylated NF-kappaB and total NF-kappaB in I/R hearts were reduced by selenium. Cardiac dysfunction in hearts perfused with xanthine plus xanthine oxidase mixture, as well as hydrogen peroxide, or subjected to Ca2+ paradox was also attenuated by selenium. These data suggest that selenium protects the heart against I/R injury due to its action on the redox state and deactivation of NF-kappaB in I/R hearts. 相似文献
4.
Ashraf Imam Cihan Karatas Nesimi Mecit Munci Kalayoglu Turan Kanmaz 《Transplantation proceedings》2021,53(5):1622-1625
BackgroundCardiovascular complication is one of the leading causes of mortality after liver transplantation (LT). Thus, a thorough cardiac evaluation is a must before proceeding to a liver transplant surgery. Percutaneous coronary intervention (PCI) with stent and to a lesser extent coronary artery bypass grafting (CABG) are both valuable treatment options for patients with coronary artery disease.MethodsA retrospective, single-center study that included patients who underwent cardiac intervention and subsequent LT for end-stage liver disease. All patients who had PCI or CABG were included in the study.ResultsTwenty-nine adult patients out of 51 had a cardiac intervention before liver transplantation. Twenty-four patients had a diagnostic PCI, 3 patients had therapeutic PCI with stent, and 2 had failed PCI and proceeded to CABG before liver transplant. The mean age of the patients was 60.5 years. There were 24 men. All patients had cirrhosis. The 2 CABG cases were done during the same admission with a 13- and 18-day interval between the CABG and the transplantation. Both cases were live-related liver transplantation. No mortality was reported.ConclusionIn case of PCI failure, CABG may be a valuable and safe treatment option for cirrhotic patients as a preparation for liver transplantation. Live donor liver transplantation may be a good back-up for those patients in case they develop hepatic decompensation. 相似文献
5.
Cis-platinum (CDDP) is a chemotherapeutic drug widely used alone or in combination with other drugs in the treatment of cancer. However, many tumors become resistant to CDDP and the mechanisms of resistance are complex. The present study investigated the role of free radicals in CDDP-mediated cytotoxicity and apoptosis. Four human ovarian cancer cell lines were chosen for the study: two lines, 222 and A2780, are sensitive to CDDP and two lines, AD10 and C30 are resistant to CDDP. The importance of free radical formation was tested by the use of an inhibitor, 2,6 di-tert-butyl-4-methoxy phenol (BHA), that inhibits the production of free radicals and detoxifies free radicals. Cytotoxicity was assessed by the MTT assay and apoptosis assessed by flow cytometric analysis of DNA hypoploidy. Three of the 4 cell lines, 222, AD10, and C30, were completely inhibited by BHA in CDDP-mediated cytotoxicity. The CDDP-sensitive A2780 cell line, however, was not inhibited by BHA, even at high non-toxic concentrations of BHA. The DNA analysis for apoptosis paralleled the findings obtained in the cytotoxicity assay. In order to rule out that the A2780 cell line was not reactive to BHA, VP-16 mediated cytotoxicity was examined. All four cell lines were sensitive to VP-16 and all four were inhibited by BHA. In contrast, there was no detectable inhibition by BHA of actinomycin-D-mediated cytotoxicity in all four lines tested. Overall, the findings demonstrate that either free-radical dependent (CDDP, VP-16) or free radical-independent (CDDP, actinomycin-D) pathways of cytotoxicity and apoptosis are utilized by different drugs. Further, a single agent like CDDP can mediate killing by both a free radical-dependent and by a free-radical independent pathway. Therefore, new agents that are developed to reverse resistance by a particular drug must take into consideration alternative cytotoxic pathways mediated by the same drug. 相似文献
6.
The purpose of this prospective study was to investigate the levels of Lp(a), Apo(a), VLDL, LDL and HDL in 23 patients with pregnancy induced hypertension (PIH) and in 20 control. The Mann-Whitney U tests was used for comparisons between the two groups. Serum Lp(a) and Apo(a) levels were sigificantly raise in the PIH group (p < 0.05 andp < 0.05 respectively) and no significant correlations could be demonstrated for other lipoproteins. 相似文献
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E E Buyukbayrak C Turan O Unal R Dansuk B Cengizo?lu 《The journal of maternal-fetal & neonatal medicine》2004,15(2):120-125
OBJECTIVE: The purpose of this study was to determine the reliability of the vaginal washing-fluid prolactin assay for the diagnosis of premature rupture of membranes (PROM) and to determine a diagnostic cut-off value. STUDY DESIGN: Seventy pregnant women between 11 and 40 weeks of gestation who were admitted with vaginal fluid leakage were included in the study group, and were then further subdivided into two subgroups according to amniotic fluid pooling and nitrazine paper test results. Group 1 was the 'confirmed PROM group', positive for both pooling and nitrazine (38 patients). Group 2 was the 'suspected but unconfirmed PROM group' which had possible pooling and/or nitrazine (32 patients). Seventy pregnant women between 11 and 40 weeks of gestation without any complaint and complication were included in the control group (group 3). All patients underwent vaginal washing-fluid sampling and prolactin level determination. For the statistical analysis one-way analysis of variance, Tukey multiple comparison test, chi2 test and receiver operating characteristic (ROC) curve analysis were used. RESULTS: Geometric mean values of vaginal washing-fluid prolactin levels were 616.59 microIU/ml for group 1, 23.98 microIU/ml for group 2 and 10 microIU/ml for group 3 (p < 0.0001). The optimal diagnostic cut-off value was found to be 30 microIU/ml with 95% sensitivity, 78% specificity, 84% positive predictive value, 93% negative predictive value, 87% accuracy and 11.30 relative risk. CONCLUSIONS: We recommend vaginal washing-fluid prolactin level determination as an alternative diagnostic method for PROM. 相似文献
9.
Buhimschi CS Turan OM Funai EF Azpurua H Bahtiyar MO Turan S Zhao G Dulay A Bhandari V Copel JA Buhimschi IA 《Obstetrics and gynecology》2008,111(3):715-722
OBJECTIVE: Fetal adaptation to stress is regulated in part by the pituitary-adrenocortical system. The stress hormones dehydroepiandrosterone sulfate (DHEAS) and cortisol have opposing effects: cortisol suppresses while DHEAS enhances immune functions. We sought to estimate the impact of intraamniotic inflammation on fetal adrenal gland volume and cortisol-to-dehydroepiandrosterone sulfate ratio (fetal stress ratio) in pregnancies complicated by preterm birth. METHODS: Fifty-one consecutive singleton fetuses of mothers who had an indicated amniocentesis to rule out infection were analyzed. Intraamniotic inflammation was assessed by proteomic profiling of amniotic fluid for the biomarkers of the Mass Restricted score. The Mass Restricted score ranges from 0 (biomarkers absent) to 4 (all biomarkers present), with Mass Restricted scores of 3 or 4 indicating severe intraamniotic inflammation. Fetal adrenal gland volume was assessed by three-dimensional ultrasonography and corrected for estimated fetal weight. Interleukin-6 (IL-6), cortisol, and DHEAS were measured by immunoassay. RESULTS: Women with intraamniotic inflammation delivered earlier (27.8+/-3.4 weeks, n=16, compared with 32.3+/-3.0 weeks, n=35, P<.001), and their fetuses had higher cord blood IL-6 (P=.011) and higher corrected adrenal gland volumes (P=.027). Cord blood IL-6 levels were in direct relationship with corrected adrenal volume (r=0.372, P=.019), fetal cortisol (r=0.428, P=.010), and DHEAS (r=0.521, P<.001). However, fetuses exposed to intraamniotic inflammation had an overall lower fetal stress ratio (P=.034). These results maintained after adjusting for gestational age, uterine contractions, and steroid exposure. CONCLUSION: Fetuses exposed to intraamniotic inflammation have higher adrenal gland volumes and lower cortisol-to-DHEAS ratios, suggesting that the fetal adrenocortical axis plays a role in the intrauterine adaptation to inflammation. 相似文献
10.
Growth-restricted fetuses are at higher risk for poor perinatal and long-term outcome than those who are appropriately grown. Multiple antenatal testing modalities can help document the sequence of fetal deterioration. The full extent of this compromise is best identified by a combination of fetal biometry, biophysical profile scoring, and arterial and venous Doppler. In the preterm growth-restricted fetus, timing of delivery is critically determined by the balance of fetal versus neonatal risks. In the near-term fetus, accurate diagnosis continues to be a challenge as unrecognized growth restriction contributes to a significant proportion of unexplained stillbirths. In this review, we present an integrated diagnostic and surveillance approach that accounts for these factors. 相似文献