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41.
PURPOSE: To correlate TP53 mutations with angiogenic status of the tumor and prognosis after liver surgery in patients with colorectal liver metastases and to correlate immunohistochemical staining of p53 protein with TP53 gene mutations. EXPERIMENTAL DESIGN: Tumors of 44 patients with surgically treated colorectal liver metastases were analyzed for (a) TP53 mutations using denaturing gradient gel electrophoresis followed by sequencing, (b) microvessel density using the hot spot overlap technique, (c) apoptotic rate in tumor cells and endothelial cells of tumor microvessels using double immunostaining for anti-cleaved caspase 3 and anti-CD34, and (d) expression of p53 protein using immunohistochemistry. RESULTS: TP53 mutations were detected in 36% of the metastases and occurred more frequently in liver metastases from left-sided colon tumors than from right-sided colon tumors (P = 0.04). In metastases with TP53 mutations, microvessel density was higher compared with tumors with wild-type p53. Endothelial cell apoptosis was not different in tumor microvessels from TP53-mutated versus nonmutated tumors. The 5-year actual survival was not influenced by TP53 mutational status, microvessel density, or endothelial cell apoptotic rate of the tumors. Based on immunohistochemical p53 overexpression, the positive and negative predictive values of TP53 mutations were 61% and 82%. CONCLUSIONS: In patients with surgically treated colorectal liver metastases, TP53 mutations and angiogenic status did not influence prognosis. Immunohistochemistry is not a reliable technique for detecting TP53 mutations.  相似文献   
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This brief commentary article considers the implications of intensive outcome monitoring which is central to children and young people's Improving Access to Psychological Therapies (CYP IAPT) in England and Wales. Services are being provided with a range of free software solutions to enable data collection, and guidance on interpretation of the measures, but there will still be some burden of data entry and collation for already overstretched services. It may be that the utility of the feedback will go some way to offset the sense of burden but this remains to be seen. Whether commissioners and others will rise to the challenge of supporting this aspect may prove crucial to the success or otherwise of such intensive ROM use. Many aspects of the CYP IAPT approach are new and whilst drawing on experience from earlier pilots of session by session monitoring in CAMHS both in the UK and abroad, and from Adult IAPT, there is likely to be much for us to learn. Time will tell whether the approach helps to improve the care children and young people receive but we are cautiously optimistic.  相似文献   
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Prostate cancer is the most common malignancy, accounting for about 25% of all incident cases among men in industrialized countries. The human androgen-dependent prostate cancer cell line LNCaP, which is derived from a metastatic lesion of human prostatic adenocarcinoma, is frequently used to study prostate cancer associated signaling pathways in vitro. Recently it was described that Rho GTPase activation in these cells leads to apoptotic responses. We used the bacterial toxins CNFy and CNF1, which specifically and directly activate Rho GTPases by deamidation of a single glutamine. We asked whether these Rho activators could induce apoptosis in LNCaP cells. Our results indicate that RhoA activation, induced by CNFy, does lead to intrinsic apoptosis of the cells. Analysis of the underlying signaling pathway reveals that apoptosis induction requires the activity of Rho kinase (ROCK) and myosin activation, an apoptotic pathway previously identified in cancer stem cells.  相似文献   
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Quantification of magnetic resonance spectroscopy signals using the phantom replacement method requires an adequate correction of differences between the acquisition of the reference signal in the phantom and the measurement in vivo. Applying the principle of reciprocity, sensitivity differences can be corrected at low field strength by measuring the RF transmitter gain needed to obtain a certain flip angle in the measured volume. However, at higher field strength the transmit sensitivity may vary from the reception sensitivity, which leads to wrongly estimated concentrations. To address this issue, a quantification approach based on the principle of reciprocity for use at 3T is proposed and validated thoroughly. In this approach, the RF transmitter gain is determined automatically using a volume‐selective power optimization and complemented with information from relative reception sensitivity maps derived from contrast‐minimized images to correct differences in transmission and reception sensitivity. In this way, a reliable measure of the local sensitivity was obtained. The proposed method is used to derive in vivo concentrations of brain metabolites and tissue water in two studies with different coil sets in a total of 40 healthy volunteers. Resulting molar concentrations are compared with results using internal water referencing (IWR) and Electric REference To access In vivo Concentrations (ERETIC). With the proposed method, changes in coil loading and regional sensitivity due to B1 inhomogeneities are successfully corrected, as demonstrated in phantom and in vivo measurements. For the tissue water content, coefficients of variation between 2% and 3.5% were obtained (0.6–1.4% in a single subject). The coefficients of variation of the three major metabolites ranged from 3.4–14.5%. In general, the derived concentrations agree well with values estimated with IWR. Hence, the presented method is a valuable alternative for IWR, without the need for additional hardware such as ERETIC and with potential advantages in diseased tissue.  相似文献   
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Purpose  

Prevention of perioperative activation of intestinal muscularis macrophages is a promising intervention to avoid post-traumatic gastrointestinal tract dysfunction. However, impaired macrophage function could have deleterious consequences on anastomotic healing, especially in complications aggravating the healing process itself, such as infectious problems either as preexisting local inflammation or infection (e.g., complicated diverticulitis) or endotoxemia due to early postoperative infections (e.g., pneumonia). Aim of this study was to investigate colonic anastomotic healing in macrophage-depleted mice in the presence of endotoxemia.  相似文献   
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