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481.
Objective: This study aims at evaluating the endometrial receptivity in uterus of pregnant rats exposed to nicotine via examination of integrin expression by immunohistochemical effect.

Methods: In this study, 16 healthy pregnant rats were divided into two groups of control and study groups each comprising eight rats. The rats randomised to study group were given a certain amount of nicotine before and during the pregnancy. Integrin expression was detected in uterus of all rats by immunohistochemical staining. The effect of nicotine exposure on embryo implantation and the endometrial receptivity were immunohistochemically and pathologically evaluated.

Results: Comparison of both groups revealed no difference in living, viable foetuses. Intensity and universality of immunohistochemical staining of Integrin β3 for endometrial epithelium and endometrial stroma were detected to be identical between the groups.

Conclusion: No immunochemical effect was observed on integrin expression, which is a very important part of receptivity in an animal model created with pregnant rats that were transdermally exposed to nicotine. Our study demonstrated that the harmful effect of nicotine use before and pregnancy on implantation is limited at the level of integrin expression, in a dose-dependent manner and also by considering the method of administration.  相似文献   

482.
Antiepileptic drugs (AED) have potential side effects through vitamin-D. Prevalence of vitamin D insufficiency and potential risk factors for the longitudinal changes of vitamin D levels compared to its baseline levels under AED treatment were investigated in this study. This retrospective study includes patients whose AED therapy were started in only autumn months, between 2000 and 2014. Detailed assessment of neurologic diagnosis and brain MRI findings, ambulatory status, types and durations of AED treatment, and baseline bone health blood tests (vitamin-D, alkaline phosphatase, calcium, and phosphate levels) were obtained on all patients. Vitamin-D deficiency was defined as 25(OH)D <20 ng/mL, while vitamin-D insufficiency was defined as 25(OH)D between 21 and 29 ng/mL. A total of 172 children (mean age 9.6 ± 4.3 years) were followed up 5.3 years in average (range 1–14.7). The mean baseline 25(OH)D level was decreased from 24.4 ± 11.6 to 19.6 ± 10.7 ng/mL at the last follow up. The mean change in the vitamin-D levels (ΔD-vitamin) was ?4.8 ng/mL (p = 0.003). The rate of vitamin-D deficiency was 54% and insufficiency was 25%. Multivariate logistic regression analysis identified only long-term use of AEDs as a risk factor for the longitudinal decrease. Monotherapy with valproic acid (n = 45), carbamazepine (n = 20), levetiracetam (n = 10) and phenobarbital (n = 12) was compared with each other. There was no difference in terms of longitudinal changes in 25(OH)D levels. In the treatment of childhood epilepsy, 25(OH)D levels should be monitored, especially when long-term AED used, in order to prevent D-hypovitaminosis.  相似文献   
483.

Objective  

Fluorine-18 fluorodeoxyglucose (FDG) uptake is frequently observed in lung hilus. This finding causes difficulties during the interpretation. Our objective was to evaluate the features of FDG uptake in lung hilus associated with benign or malignant etiology in patients with thoracic and non-thoracic tumors.  相似文献   
484.

Purpose

To investigate the contribution of preoperative apparent diffusion coefficient (ADC) values in the differential diagnosis of pediatric posterior fossa tumors.

Methods

Forty-two pediatric patients (mean age 7.76 ± 4.58 years) with intra-axial tumors in the infra-tentorial region underwent magnetic resonance imaging. ADC measurement was performed using regions of interest, obtained from the solid component of the mass lesions. ADC ratios were calculated by dividing the ADC values from the mass lesions by the ADC values from normal cerebellar parenchyma. Lesions were categorized as juvenile pilocytic astrocytoma (JPA), ependymoma and medulloblastoma based on histopathological diagnosis. ADC values of the lesions and histopathological diagnoses were statistically correlated.

Results

Histopathological diagnosis showed that 14 lesions were JPA, 10 were ependymoma; 18 were medulloblastoma. Both ADC values and ADC ratios were significantly correlated with tumor types (p <0.05). Astrocytoma was distinguished from ependymoma with sensitivity 85.7% and specificity 90% using an ADC ratio ≥1.7 and medulloblastoma was distinguished from ependymoma with sensitivity 100% and specificity 88.89% using an ADC ratio ≤1.18.

Conclusion

Preoperative ADC values could differentiate the main histological subtypes of pediatric posterior fossa tumors with high sensitivity and specificity.
  相似文献   
485.
AIM: The aim of the paper was to investigate whether thoracic epidural anesthesia (TEA) together with general anaesthesia (GA) play a role on apoptosis in humans before cardiopulmonary bypass (CPB), before aortic cross clamp (ACC) and at 15 min after ACC release (after ischemia and reperfusion). METHODS: Eighty patients scheduled for elective CABG were randomized to receive either GA group (n: 40) or TEA+GA group (n: 40). The right atrial biopsy samples were taken before CPB, before ACC and at 15 min after ACC release from all patients. Human heart tissues were obtained from patients of TEA+GA group and GA group. The number of Bcl-2 positive cardiomyocytes was counted in multiple tissue sections of biopsies of 80 patients using light microscopy (magnification x 40) with an ocular micrometer system (Olympus). RESULTS: In the TEA+GA group, the Bcl-2 positive cardiomyocytes were distinctly statistically increased compared to the GA group (P<0.001). In addition, the intensity of the immunostaining was also increased in the TEA+GA compared with the GA group. The number of immunoreactive cardiomyocytes is as follows: before CPB, TEA+GA group 396+/-61, GA group 92+/-41, before ACC, TEA+GA group 333+/-47, GA group 94+/-18, at 15 min after ACC release, TEA+GA group 346+/-68.8, GA group 85+/-9.5. There were statistically significant differences between groups, (P<0.001). Between groups, at 4 h and at 24 h after the end of CPB, in the TEA+GA group, the CI was significantly higher than GA group respectively; (3.4+/-0.8 L/min/m(2) vs 2.5+/-0.8 L/min/m(2); P<0.001), (3.8+/-1.1 L/min/m(2) vs 3.1+/-1.1 L/min/m(2); P<0.008). Within groups, at 4 and 24 h after the end of CPB, in the TEA+GA group, the CI was significantly higher than baseline values, respectively, (3.4+/-0.8 L/min/m(2) vs 2.4+/-0.7 L/min/m(2); P<0.001), (3.8+/-1.1 L/min/m(2) vs 2.4+/-0.7 L/min/m(2); P<0.001). Whereas no difference was found in the GA group respectively, (2.6+/-0.8 L/min/m(2) vs. 2.5+/-0.8 L/min/m(2); P>0.05), (2.6+/-0.8 L/min/m(2) vs. 3.1+/-1.1 L/min/m(2); P>0.05). The number of patients showing ventricular fibrillation (VF), atrial fibrillation or heart block after release of the ACC was 11 of 40 (27.5%) in the TEA+GA group versus 25 of 40 (62.5%) in the GA group. The number of patients showing VF after release of ACC was 9 out of 20 patients (22.5%) in the TEA+GA group which was significantly lower than in the GA group (21 of 40 patients 52.5%); (P<0.006). Sinus rhythm after release of ACC, in the TEA+GA group was observed in 29 of 40 patients (72.5%) and was significantly higher than in the GA group (15 of 40 patients 37.5%); (P<0.002). CONCLUSION: The result of the present study indicate that TEA plus GA in coronary surgery had preserved cardiac function during intraoperative and postoperative period by means of reduced apoptosis, improved hemodynamic function and reduced arrhythmias after release of the ACC.  相似文献   
486.
1. Increased oxidative stress has an important role in the pathogenesis of diabetic nephropathy. The aim of the present study was to evaluate diabetic nephropathy by determining markers of oxidative stress and the urinary excretion of N-acetyl-beta-D-glucosaminidase (NAG), albumin and to investigate the possible protective effects of in vivo melatonin on renal tubular oxidative damage in diabetic rats. 2. Twenty-six rats were randomly divided into three groups: (i) group I, control, non-diabetic rats (n = 9); (ii) group II, untreated diabetic rats (n = 8); and (iii) group III, melatonin-treated diabetic rats (n = 9). In groups II and III, diabetes developed 3 days after administration of a single dose of streptozotocin (35 mg/kg, i.p.). Thereafter, whereas the rats in group II received no treatment, rats in group III began to receive 10 mg/kg per day, i.p., melatonin for 8 weeks. Malondialdehyde (MDA), an index of lipid peroxidation, NAG and microalbumin in the urine, markers of renal tubular damage, were the parameters used for oxidative stress-induced renal injury. Superoxide dismutase (SOD), xanthine oxidase (XO) and glutathione peroxidase (GSH-Px) activities were determined to evaluate changes in the anti-oxidant status of kidney tissue. 3. In untreated diabetic rats, urinary NAG, albumin and renal MDA levels were markedly increased compared with control rats (P < 0.0001). However, these parameters were reduced in diabetic rats by melatonin treatment (P < 0.0001). Urinary excretion of NAG was positively correlated with the microalbuminuria and renal MDA levels (r = 0.8; P < 0.0001). The SOD and XO activities in the untreated diabetic group were found to be significantly higher than those of the control group (P < 0.0001). Superoxide dismutase and XO activities decreased in melatonin-treated rats compared with untreated diabetic rats (P < 0.002 and P < 0.023, respectively). However, the decrease did reach levels seen in control rats. There were no significant differences in GSH-Px activity between the three groups. 4. Therefore, on the basis of these data, we suggest that urinary NAG, albumin excretion, XO activity and MDA levels are more valuable parameters showing the degree of renal tubular injury than classical markers of oxidative stress, including SOD and GSH-Px, in diabetic rat kidneys. Melatonin has an ameliorating effect on oxidative stress-induced renal tubular damage via its anti-oxidant properties. Thus, it may be suggested that urinary NAG excretion and microalbuminuria may be important markers showing the degree of renal changes and the success of long-term treatment of renal impairment with melatonin.  相似文献   
487.
488.
Thiol-modifying agents induce the release of nitric oxide (NO) from endothelial epithelium and the release of reactive oxygen free radicals in the vascular system. Moreover, thiol groups are essential for the functioning of the ATP dependent potassium channel (K-ATP). The effects of thiol-modifying agents and their molecular mechanisms on arrhythmia have not been widely studied. In this study, we investigated the effect of the hydrophilic SH-group-oxidizing substance thimerosal on the arrhythmia induced by reperfusion/ischemia after coronary artery ligation in rats. We studied the possible involvement of the K-ATP and NOS on the effect of thimerosal. Thimerosal pretreatment (3, 30 mg/kg dose iv. 10 minutes before coronary occlusion) significantly decreased the length of total arrhythmia, ventricular tachycardia, and the arrhythmia score. This effect of thimerosal was reversed by the K-ATP opener pinacidil but not by the K-ATP blocker glibenclamide. The inhibition of iNOS by L-NAME did not alter the antiarrhythmic effect of thimerosal. These data clearly suggest that the antiarrhythmic effect of thimerosal is dependent upon the blockage of K-ATP.  相似文献   
489.
A 14-year-old boy presented with a pink firm plaque with well-defined borders in the right infra-orbital skin area. On diascopy, the infiltrate exhibited a typical apple-jelly appearance. No acid-fast bacilli could be demonstrated. A polymerase chain reaction (PCR) assay did not reveal the presence of mycobacteria in a lesional biopsy sample. Culture of biopsied tissue on Loewenstein-Jensen medium was negative. Although the tuberculosis culture and PCR did not confirm tuberculosis, a diagnosis of lupus vulgaris was made considering the clinical and histopathological findings. After a 9-month antituberculous therapy, the lesion disappeared. We believe that a diagnosis of lupus vulgaris still depends more on clinical and histopathological findings than on tuberculosis culture or PCR.  相似文献   
490.
Crystalline silica has been classified as a human carcinogen, but there is still considerable debate on its variable fibrogenic and carcinogenic potential. We investigated genotoxicity of a panel of four quartz flours in comparison to DQ12 standard quartz with similar size and surface area, using single cell gel electrophoresis (SCGE) or comet assay. A549 human lung epithelial cells were incubated for 4 hours with different concentrations of quartz ranging from 1.6 to 200 micrograms/cm2 and cytotoxicity was assessed using leakage of lactate dehydrogenase (LDH), trypan blue exclusion and conversion of a metabolic substrate (MTT). DNA strand breakages were seen with all quartzes at an in vitro concentration of 200 micrograms/cm2. At this concentration all tests and quartz samples showed significant cytotoxicity. The most toxic quartz flour (Qz 2/1-C) but not DQ12, showed an increase in strand breaks at 40 micrograms/cm2 in cell culture. At this concentration no cytotoxicity was seen with LDH and MTT, but a significant increase in cells with trypan blue uptake was noted. No differences in tail moment percentage were observed at equal concentrations of different quartz flours. Also no correlation between DNA damage and OH-radical generation or surface radicals as measured by electron spin resonance was observed. We conclude that quartzes do not cause strand breaks without concomitant cell toxicity and a sufficient in vitro concentration of > 40 micrograms/cm2 can only be reached in vivo with instillation of massive doses (> 100 mg). Therefore, in vitro genotoxicity found here is unlikely to explain the genotoxicity observed in in vivo studies with the same and other quartzes.  相似文献   
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