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101.
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TCDD, as an endocrine disruptor, is known to impair testicular functions and fertility. To elucidate the mechanism(s) underlying the testicular effects of TCDD, the potential toxicity of TCDD on Sertoli cells was investigated. Furthermore, the study aims to delineate whether mitochondrial fractions of Sertoli cells are involved in mediating the testicular effects of TCDD. Adult rat Sertoli cells were incubated with (5, 10 or 15 nM) of TCDD for 6, 12 or 24 h. Cell viability, lactate and LDH leakage into media along with lipid peroxidation, ROS generation, SOD, CAT, GPx, GR, γ-GT and β-glucuronidase activities, GSH content and Δψm were measured. Superoxide anion production, COX and cardiolipin content were measured in mitochondrial fractions. Cell viability was significantly decreased while lactate and LDH leakage into media were increased. ROS generation along with lipid peroxidation was also increased. SOD, CAT, GPx, GR activities and GSH content were significantly decreased. γ-GT and β-glucuronidase activities were also decreased. Superoxide anion production was increased while COX activity and cardiolipin content were decreased in mitochondrial fractions. Moreover, the Δψm was significantly decreased as measured in Sertoli cells. In conclusion, TCDD impairs Sertoli cell functions and this effect is, at least in part, attributed to oxidative stress. We have also found that TCDD increases mitochondrial superoxide anion production and decreases Δψm, COX activity and mitochondrial cardiolipin content. Our findings suggest that mitochondria may play an important role in ROS production, leading to the TCDD-induced oxidative stress response and resulting toxicological consequences in rat Sertoli cells. 相似文献
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The management of cervical lymph node metastases of squamous cell carcinoma from an unknown primary site is still a therapeutic challenge.We report here our experience in treating these patients with chemoradiotherapy as a curative approach.Data from 40 patients were reviewed.In total,20(50%) patients underwent excisional biopsy.All patients underwent radiotherapy,which was delivered to both sides of the neck and pharyngeal mucosa(extensive field),and concurrent chemotherapy consisting of weekly cisplatin at a dose of 40 mg/m2.The clinical stage of the cervical nodes at presentation was N1 in 25%,N2 in 60%,and N3 in 15%.Most patients(75%) developed at least grade 3 mucositis.Eight patients(20%) had grade 3 xerostomia and 18 patients(45%) required esophageal dilation for stricture.The 5-year overall survival(OS) rate of all patients was 67.5%.The 5-year OS rates of patients with N1,N2,and N3 lesions were 100%,67%,and 41%,respectively(P = 0.046).The 5-year progression-free survival rate was 62.5%.In multivariate analysis,only N stage significantly affected OS(P = 0.022).Emergence of the occult primary was very limited(1 patient only).Our results suggest that extensive irradiation of both sides of the neck and pharyngeal mucosa with concurrent chemotherapy results in a lower emergence of primary tumor.Because the survival of patients with unknown primary is comparable to that of patients with known primary,an attempt at cure should always be made. 相似文献
105.
Rasha Bassam Juergen Hescheler Ayseguel Temiz-Artmann Gerhard M Artmann Ilya Digel 《BMC biophysics》2012,5(1):1-7
Background
Minor changes in protein structure induced by small organic and inorganic molecules can result in significant metabolic effects. The effects can be even more profound if the molecular players are chemically active and present in the cell in considerable amounts. The aim of our study was to investigate effects of a nitric oxide donor (spermine NONOate), ATP and sodium/potassium environment on the dynamics of thermal unfolding of human hemoglobin (Hb). The effect of these molecules was examined by means of circular dichroism spectrometry (CD) in the temperature range between 25°C and 70°C. The alpha-helical content of buffered hemoglobin samples (0.1 mg/ml) was estimated via ellipticity change measurements at a heating rate of 1°C/min.Results
Major results were: 1) spermine NONOate persistently decreased the hemoglobin unfolding temperature T u irrespectively of the Na + /K + environment, 2) ATP instead increased the unfolding temperature by 3°C in both sodium-based and potassium-based buffers and 3) mutual effects of ATP and NO were strongly influenced by particular buffer ionic compositions. Moreover, the presence of potassium facilitated a partial unfolding of alpha-helical structures even at room temperature.Conclusion
The obtained data might shed more light on molecular mechanisms and biophysics involved in the regulation of protein activity by small solutes in the cell. 相似文献106.
107.
Hanan Fouad Maissa Saeed El Raziky Rasha Ahmed Abdel Aziz Dina Sabry Ghada Mahmoud Abdel Aziz Manal Ewais Ahmed Reda Sayed 《World journal of gastroenterology : WJG》2013,19(43):7711-7718
AIM:To assess co-stimulatory and co-inhibitory markers of dendritic cells(DCs)in hepatitis C virus(HCV)infected subjects with and without uremia.METHODS:Three subject groups were included in the study:group 1 involved 50 control subjects,group2 involved 50 patients with chronic HCV infection and group 3 involved 50 HCV uremic subjects undergoing hemodialysis.CD83,CD86 and CD40 as co-stimulatory markers and PD-L1 as a co-inhibitory marker were assessed in peripheral blood mononuclear cells by realtime polymerase chain reaction.Interleukin-10(IL-10)and hyaluronic acid(HA)levels were also assessed.All findings were correlated with disease activity,viral load and fibrogenesis.RESULTS:There was a significant decrease in costimulatory markers;CD83,CD86 and CD40 in groups2 and 3 vs the control group.Co-stimulatory markers were significantly higher in group 3 vs group 2.There was a significant elevation in PD-L1 in both HCV groups vs the control group.PD-L1 was significantly lower in group 3 vs group 2.There was a significant elevation in IL-10 and HA levels in groups 2 and 3,where IL-10was higher in group 3 and HA was lower in group 3 vs group 2.HA level was significantly correlated with disease activity and fibrosis grade in group 2.IL-10 was significantly correlated with fibrosis grade in group 2.There were significant negative correlations between co-stimulatory markers and viral load in groups 2 and3,except CD83 in dialysis patients.There was a significant positive correlation between PD-L1 and viral load in both HCV groups.CONCLUSION:A significant decrease in DC co-stimulatory markers and a significant increase in a DC coinhibitory marker were observed in HCV subjects and to a lesser extent in dialysis patients. 相似文献
108.
Sherif M.M. Negm Rasha A. Kamel Ahmed M. Magdi Fouad A. Abuhamila Maged Al-Mohamady 《Middle East Fertility Society Journal》2012,17(4):283-289
ObjectiveThe aim of the study was to correlate serum AMH and serum FSH levels with ovarian response to stimulation in IVF–ICSI cycles.Design and settingsThis was a prospective observational study conducted in a private assisted conception unit.Subjects and methodsOne hundred and two patients were selected on their first IVF cycle. Basal serum FSH and serum AMH were measured one month before the stimulation cycle. A fixed dose GnRH antagonist protocol was used in all cycles transferring a maximum of three day-3 cleavage stage embryos. We defined poor ovarian response as retrieval of fewer than four mature oocytes in cycles requiring ? 3000 IU of gonadotropins for stimulation or cycle cancellation due to poor response. The correlation between different parameters was expressed as a Spearman’s correlation coefficient. The clinical value of AMH and FSH as predictors of poor ovarian response as well as predictors of pregnancy was evaluated by constructing relevant receiver operator characteristics curves (ROC curves).ResultsOf these 102 cycles, 28 fitted our definition of poor response while the remaining 74 cycles all produced an adequate response to stimulation. There was a statistically significant difference between the adequate responders group and poor responders group regarding their mean age (31.5 versus 39.6, p < 0.001), the mean value of AMH (2.84 ng/ml versus 0.9 ng/ml, p < 0.0001) as well as the mean value of basal FSH (7.6 IU/ml versus 9.7 IU/ml, p < 0.0001). Serum AMH level had a positive correlation while serum FSH had a negative correlation with the number of oocytes collected while only serum AMH had a significant positive correlation with the occurrence of pregnancy. ROC curve analysis of our results showed that serum AMH with an optimal cut-off value of 1.2 ng/ml is a reliable predictor of poor ovarian response with an area under the ROC curve of 90.4%. Serum basal FSH with an optimal cut-off value of 8.9 IU/ml was of lower value than AMH as a predictor of poor ovarian response with an area under the ROC curve of 81.9%. However, neither serum AMH nor basal serum FSH was found to able to reliably predict the occurrence of pregnancy with an area under the ROC curve of 59.4% and 58.6% respectively.ConclusionOur results show that serum AMH level is more reliable than basal serum FSH as a predictor of poor ovarian response to stimulation with a cut-off value of 1.2 ng/ml shown to predict poor ovarian response with a sensitivity of 91.7%. 相似文献
109.
Blum J Raghavan S Dabash R Ngoc Nt Chelli H Hajri S Conkling K Winikoff B 《International journal of gynaecology and obstetrics》2012,118(2):166-171
ObjectiveTo assess the potential advantages of combined mifepristone–misoprostol versus misoprostol-only for early medical abortion.MethodsA double-blind randomized placebo controlled study was conducted that enrolled 441 pregnant women (< 63 days since last menstrual period) at 2 hospitals in Tunisia and Vietnam. The mifepristone–misoprostol group (n = 220) received 200 mg of mifepristone on day 1 and 800 μg buccal misoprostol followed by placebo 3 hours later on day 2. The misoprostol-only group (n = 221) received placebo on day 1 and 1600 μg of misoprostol (2 doses of 800 μg, given 3 hours apart) on day 2. All medications were self-administered at home with follow-up 1 week later. The primary outcome was complete uterine evacuation without surgical intervention.ResultsSuccessful uterine evacuation occurred for 78.0% (n = 170) of women with misoprostol only versus 92.9% (n = 195) of women with mifepristone–misoprostol (relative risk 0.84, 95% CI, 0.78–0.91; P < 0.001). Ongoing pregnancy occurred for 13.8% (n = 30) of women given misoprostol-only and 1.4% (n = 3) of women given mifepristone–misoprostol (relative risk 9.63, 95% CI 2.98–31.09; P < 0.001).ConclusionMifepristone plus misoprostol is significantly more effective than misoprostol-only for early medical abortion.Clinical trials.gov registration number: NCT00680394. 相似文献
110.
Ahmed E. Arafa Rasha S. Elbahrawe Sherwet M. Shawky Ahmed M. Abbas 《Middle East Fertility Society Journal》2018,23(3):184-188