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111.
There are controversies regarding pain expression in mentally disabled people, including Down syndrome patients. The aim of this study was to examine neuropathic pain-related behavior and peripheral nerve regeneration in mouse model of Down syndrome. Sciatic nerves of double transgenic mice, overexpressing both amyloid precursor protein (APP) and Cu/Zn superoxide dismutase (SOD1) genes, and FVB/N wild type mice were transected and immediately resutured. Evaluation of autotomy and functional recovery was carried out during 4-week follow-up. We found markedly less severe autotomy in transgenic animals, although the onset of autotomy was significantly delayed in control mice. Interestingly, neuroma formation at the injury site was significantly more prominent in transgenic animals. Sciatic function index outcome was better in transgenic mice than in wild-type group. Histological evaluation revealed no statistically significant differences in the number of GAP-43-positive growth cones and macrophages in the distal stump of the transected nerve between groups. However, in transgenic animals, the regenerating axons were arranged more chaotically. The number of Schwann cells in the distal stump of the transected nerves was significantly lower in transgenic mice. The number of surviving motoneurons was markedly decreased in transgenic group. We measured also the atrophy of denervated muscles and found it decreased in APP/SOD1 overexpressing mice. Taken together, in this model of Down syndrome, we observed increased neuroma formation and decreased autotomy after peripheral nerve injury. Our findings suggest that APP/SOD1 overexpressing mice are less sensitive for neuropathic pain associated with neuroma.  相似文献   
112.
In contrast to the occurrence of brain metastases advanced malignant tumours in adult cancer patients, the dissemination of solid tumours to the brains of paediatric cancer patients is very uncommon. We present a neuro-pathological and clinical study of a group of children and adolescents with brain metastases (BM) from extracranial solid malignancies. The analysed patients were diagnosed with soft tissue sarcomas (three), germ cell tumours (three), or osteosarcoma, neuroblastoma, clear cell sarcoma of the kidney, or pleuropulmonary blastoma (one each). In our series, BM frequently coexisted with pulmonary metastases. Three different metastatic patterns were discernible: a solitary tumour, multiple lesions and diffuse parenchymal dissemination. Two cases showed haemorrhagic presentation. Most of the children died due to BM progression, while children with germ cell tumours showed the best prognosis. The histopathological pictures of BM can be different from the primary tumour, showing dedifferentiation or a diverse neoplastic component. The autopsy examination can still be helpful in the final diagnosis of certain cases with atypical clinical presentations.  相似文献   
113.
The aim of our study was to investigate the correlation of the clinical characteristic of pineal parenchymal tumors in children and adolescent with histopathological diagnosis and patient survival. Records of 27 patients with histologically diagnosed pineocytomas (n = 16) and pineoblastoma (n = 11) consecutively treated between 1991 and 2001 were reviewed retrospectively to identify factors predictive of aggressiveness. Among analyzed epidemiological, clinical, and radiological factors, we found that independent prognostic indicator in patients with childhood pineal parenchymal tumor was the extent of surgical resection.  相似文献   
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117.

Objectives

Mucinous adenocarcinoma of the endometrium (MUC) is a rare histological variant of endometrial carcinoma accounting for 1-9% of endometrioid tumors. Few studies have characterized its clinical behavior. This is a case-control study at a single institution comparing the risk factors and clinical course of MUC relative to endometrioid adenocarcinoma.

Methods

A case-control study was performed including patients treated for endometrial cancer between 1996 and 2006. 41 cases of mucinous adenocarcinoma were identified. Each case was matched with two controls of endometrioid histology by age and histological grade. Cases and controls were compared with regard to known risk factors for endometrial cancer and the extent of disease at diagnosis. Chi-square tests were used to compare proportions and Student's t-tests for the comparison of means. Multivariate regression was used to identify the independent predictors of lymph node metastases. Overall survival was calculated using the Kaplan-Meier method and compared with the Log-rank test. p < .05 was considered significant for all tests.

Results

Cases and controls were matched by age and FIGO grade and were found to be similar in regard to ethnicity, body mass index and medical history. No significant difference in myometrial invasion (MI) > 50% or the presence of lymph-vascular space invasion was found between cases and controls, however, 17% of patients with MUC had lymph node metastases compared to 3% of controls (p = .01). Multivariate analysis controlling for both tumor grade and depth of MI identified mucinous histology as an independent predictor of lymph node metastasis (p = .02). There was no difference in adjuvant treatment, recurrence rate or survival between the two groups.

Conclusion

Mucinous differentiation was found to be an independent predictor of lymph node metastasis in the study population. Comprehensive surgical staging including retroperitoneal node dissection should be strongly considered in all endometrial cancer patients with predominantly mucinous histology.  相似文献   
118.

Objectives

The purpose of this study was to assess the value of contrast-enhanced magnetic resonance cholangiography (MRC) performed in different time delays after injection of gadoxetic acid disodium (Gd-EOB-DTPA) for the diagnosis of active bile leak.

Methods

This retrospective analysis included Gd-EOB-DTPA enhanced MR images of 34 patients suspected of bile leak. Images were acquired 20–25 min after Gd-EOB-DTPA injection. If there was inadequate contrast in the bile ducts then delayed images after 60–90 min and 150–180 min were obtained. Results were correlated with intraoperative findings, ERCP results, clinical data, laboratory tests, and follow-up examinations.

Results

Gd-EOB-DTPA enhanced MRC yielded an overall sensitivity of 96.4%, specificity of 100% and accuracy of 97.1% for the diagnosis of an active bile leak. The sensitivity of 20–25 min delayed MR images was 42.9%, of combined 20–25 min and 60–90 min delayed images was 92.9% and of combined 20–25 min, 60–90 min and 150–180 min delayed images was 96.4%.

Conclusions

Gd-EOB-DTPA enhanced MRC utilizing delayed phase images was effective for detecting the presence and location of active bile leaks. The images acquired 60–180 min post-injection enabled identification of bile leaks even in patients with a dilated biliary system or moderate liver dysfunction.  相似文献   
119.
The aim of the study was to assess the toxicity of a range of trace metals to the rotifer Lecane inermis, a species tested as a potential biological tool to control activated sludge bulking caused by overgrowth of filamentous bacteria in wastewater treatment plants. LC50 values (concentration lethal to 50 % of individuals, mg dm?3) were ranked in the following order: Cu < Al < Fe < Zn < Sn < Mn. L. inermis apparently is more sensitive to metals than other aquatic species widely used as model organisms in ecotoxicological testing, making it potentially useful for quick ecotoxicological tests.  相似文献   
120.

Purpose

Light-at-night exposure can disrupt the human circadian rhythm via clock gene expressions. The circadian rhythm influences antioxidant enzymes’ activity and cellular mRNA levels of these enzymes. The employees working based on a shift system adjust to the changes occurring both on the cell level and on the level of the whole organism. Therefore, a question should be answered whether shift work disturbs oxidant–antioxidant balance and/or generates oxidative stress.

Methods

A cross-sectional study was conducted among nurses selected from the Local Registry of the Chamber of Nurses and Midwives in Lodz: 359 nurses worked daily only and 349 working rotating night shifts. These two groups differed significantly in respect of age (p < 0.0001), menopausal status (p < 0.0001), and current smoking habit (p = 0.02). The average total work duration was significantly shorter (12.4 years) in nurses working currently rotating night shifts who worked significantly longer on night shifts than day-workers (26.6 years).

Results

We found statistically significant higher red blood cell glutathione peroxidase in nurses working on night shifts (21.0 ± 4.6 vs. 20.0 ± 5.0 U/g Hb, p < 0.009) after adjusting for age, oral contraceptive hormone use, smoking, and drinking alcohol during last 24 h. Statistically significant lower vitamin A and E levels were found in the premenopausal women working in rotating system (0.690 ± 0.238 vs. 0.786 ± 0.262 μg/ml, p < 0.0001 for vitamin A and 10.93 ± 4.15 vs. 12.78 ± 4.75 μg/ml, p < 0.0001 for vitamin E). The marker of lipid peroxidation (TBARS concentration) was significantly lower in the premenopausal nurses than postmenopausal ones working day shifts only (2.06 ± 0.76 vs. 2.21 ± 0.80 nmol/ml, p < 0.038). We observed that erythrocyte GSH-Px activity rose statistically significant in nurses working more night shifts per month (p < 0.01).

Conclusions

The results quoted above seem to support the existence of an association between light-at-night exposure and blood glutathione peroxidase activity in female shift workers. Nevertheless, in order to explain the mechanisms of this association, we need more studies.  相似文献   
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