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101.
Gliomas are the most frequent primary tumors of the central nervous system in adults. The most prevalent and aggressive subclass of these is glioblastoma multiforme, which is characterized by massive neovascularization. Endosialin (CD248) has generated interest as a target for antiangiogenic therapy following reports that its expression is upregulated on angiogenic endothelial cells. We demonstrate here that endosialin is not expressed in normal human adult brain but is strongly upregulated in the angiogenic vasculature of all high-grade glioma specimens examined. However, by taking advantage of a technique which allows for multiple fluorescent labeling of formalin-fixed paraffin-embedded archival sections, we demonstrate unambiguously that endosialin is not expressed by the glioma endothelial cells but on closely associated perivascular cells. With increasing awareness that targeting pericytes is an attractive adjunct in antiangiogenic therapy, this finding has important implications for understanding the molecular mechanisms regulating angiogenesis in these highly vascularized tumors.  相似文献   
102.
Objective: Constipation is a common adverse effect in patients requiring long-term opioid therapy for pain control. Methylnaltrexone, a quaternary peripheral mu-opioid receptor antagonist, is an effective treatment of opioid induced constipation (OIC) without affecting centrally mediated analgesia. Our objective was to conduct a review and meta-analysis to evaluate the efficacy of methylnaltrexone for treatment of OIC, as well as to provide a clinical discussion regarding newly developed alternatives and provide the current treatment algorithm utilized at our institution.

Methods: We performed a systematic review and meta-analysis of randomized control trials using Cochrane Collaboration Databases and MEDLINE from 2007-present. Literature related to methylnaltrexone, opioids, opioid receptors, opioid antagonists, opioid-induced constipation were reviewed. A meta-analysis was completed with the primary outcome of rescue-free bowel movement (RFBM) within four hours of administration. All pooled analyses were based on random-effects models.

Results: 1239 patients were analyzed; 599 received methylnaltrexone and 640 received placebo. With a 95% CI calculated, the true risk difference is between 0.267 and 0.385, demonstrating a statistically significant difference in RFBM between treatment and placebo groups (p < 0.0001). Both the 0.15 mg/kg, 0.30 mg/kg doses every other day, and 12 mg/day dose were found to have increased risk of RFBM compared to placebo.

Conclusion: Results support the use of methylnaltrexone. Furthermore, the use of methylnaltrexone to induce laxation may decrease use of health care resources, increase work productivity, and improve cost utilization. New treatments have been made available; however, controlled clinical studies are needed to demonstrate long–term efficacy, safety and cost–effectiveness. Possible limitations of this study include the relatively small number of randomized, placebo-controlled trials investigating the efficacy of methylnaltrexone versus placebo. There is also the possibility of publication bias, which may lead to overestimating the efficacy of methylnaltrexone in treating OIC.  相似文献   

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Congenital dyserythropoietic anaemias (CDAs) are heterogeneous, hereditary disorders hallmarked by ineffective erythropoiesis and tissue iron overload. Growth differentiation factor 15 (GDF15) was suggested to mediate iron overload in iron-loading anaemias, such as the thalassaemias and CDAI by suppressing hepcidin, the key regulator of iron absorption. Here, we show that serum GDF15 concentrations are elevated in subjects with CDAI and CDAII. Despite similar disease characteristics, CDAI patients present with significantly higher GDF15 concentrations compared to CDAII patients. Hepcidin concentrations are inappropriately low in CDAII patients considering the severe hepatic iron overload associated with this disorder. GDF15 significantly correlates with the degree of anaemia (Hb), the response of erythropoiesis (reticulocyte index) as well as with iron availability in the serum (transferrin saturation). The observation that GDF15 is elevated in CDAII patients is consistent with the proposal that GDF15 is among the erythroid factors down-regulating hepcidin and contributing to iron overload in conditions of dyserythropoiesis.  相似文献   
105.

Background

Several studies in the literature have investigated the possible role of the extent of lymphadenectomy in gastric cancer treatment failure. The current study attempted to determine the effectiveness and safety of lymphadenectomy with gastrectomy for the treatment of gastric cancer.

Methods

Randomized controlled trials (RCTs) were identified by means of MEDLINE, EMBASE, Cochrane Controlled Trials Register databases, and Chinese Biomedical Database, as well as by selecting references from relevant articles.

Results

Overall, 14 RCTs (3,432 patients) were included in the meta-analysis. Of the D1 and D2 surgery groups, the operative mortality and postoperative morbidity were higher in the D2 group than in the D1 group, but the 3- and 5-year survival rates were not statistically different. Also the operative time was shorter in D1 compared to D2. In the D2 versus the D3 surgical group, the operative mortality, percentage of postoperative complications, operative time, and hospital stay were not significantly different.

Conclusions

The results suggest that D2 and D3 surgery may not offer specific advantages for gastric cancer and instead may lead to disadvantages for patient outcomes.  相似文献   
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To significantly improve the biocompatibility of titanium doped phosphate based glasses, codoping with zinc has been attempted. This study investigated the effect of doping a quaternary 15Na(2)O:30CaO:5TiO(2):50P(2)O(5) glass with zinc oxide (1, 3, and 5 mol %) on bulk, structural, surface, and biological properties; the results were compared with glasses free from ZnO and/or TiO(2). ZnO as adjunct to TiO(2) was effective in changing density, interchain bond forces, degradation behavior, and ions released from the degrading glasses. Incorporation of both TiO(2) and ZnO in T5Z1, T5Z3, and T5Z5 glasses reduced the level of Zn(2+) release by two to three orders of magnitude compared with glasses containing ZnO only (Z5). (31)P NMR results for T5Z1, T5Z3, and T5Z5 glasses showed the presence of Q(3) species suggesting that the TiO(2) is acting as a network former, and the phosphate network becomes slightly more connected with increasing ZnO incorporation. Regardless of their relative lower hydrophilicity and surface reactivity compared with the control glass free from TiO(2) and ZnO (T0Z0), these glasses have significantly higher surface reactivity compared with Thermanox. This has been also reflected in the maintenance of >98% viable Osteoblasts, proliferation rate, and expression level of osteoblastic marker genes in a comparable manner to Thermanox and T5 glasses, particularly T5Z1 and T5Z3 glasses. However, T0Z0 and Z5 glasses showed significantly reduced viability compared to Thermanox. Therefore, it can be concluded that ZnO doped titanium phosphate glasses, T5Z1 and T5Z3 in particular, can be promising substrates for bone tissue engineering applications.  相似文献   
110.
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