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Endometrial carcinomas are classified by their morphology into two major subtypes. Endometrioid carcinomas (type I) are generally estrogen dependent, well-differentiated, superficially invasive, and have a good outcome. Serous carcinomas (type II) are hormone independent, frequently deeply invasive and widely metastatic, and have a poor prognosis. Microarray technology and analysis allows us to determine if the global gene expression profiles of these two subtypes correlate with their morphologic phenotype. Fresh tissue from 18 endometrial carcinomas was studied: 7 well-, 2 moderately, and one poorly differentiated endometrioid, 4 serous carcinomas, and 4 high-grade mixed endometrioid-serous carcinomas. Labeled cDNA probes were synthesized (Cy5 for tumor, Cy3 for reference) and applied to microarrays containing 18,098 cDNA clones or ESTs. A pool of equal amounts of total RNA from each tumor served as the reference RNA. By unsupervised cluster analysis, the endometrioid carcinomas clustered together and were separate from the serous carcinomas. The high-grade mixed carcinomas clustered with the serous carcinomas. Using a statistical algorithm based on gene expression pattern and conducting a supervised analysis of the two defined groups, we have identified 315 genes that statistically differentiate type I from type II endometrial carcinomas. In addition to corroborating the predicted overexpression of known markers (e.g., ras and catenin in endometrioid carcinomas), the cDNA microarray technique has revealed novel alterations in gene expression relevant to cell cycle, cell adhesion, signal transduction, apoptosis, and tumor progression not previously implicated in endometrial carcinomas. For serous carcinomas, these include aldolase, desmoplakin, integrin-linked kinase, PKC, and metallopeptidase. In conclusion, the gene expression profiles of type I and type II endometrial carcinomas are different. Refinement of these profiles will permit more accurate diagnostic tumor classification and the development of prognosis assays.  相似文献   
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Hydrogels, three-dimensional (3D) polymer networks, present unique properties, like biocompatibility, biodegradability, tunable mechanical properties, sensitivity to various stimuli, the capacity to encapsulate different therapeutic agents, and the ability of controlled release of the drugs. All these characteristics make hydrogels important candidates for diverse biomedical applications, one of them being drug delivery. The recent achievements of hydrogels as safe transport systems, with desired therapeutic effects and with minimum side effects, brought outstanding improvements in this area. Moreover, results from the utilization of hydrogels as target therapy strategies obtained in clinical trials are very encouraging for future applications. In this regard, the review summarizes the general concepts related to the types of hydrogel delivery systems, their properties, the main release mechanisms, and the administration pathways at different levels (oral, dermal, ocular, nasal, gastrointestinal tract, vaginal, and cancer therapy). After a general presentation, the review is focused on recent advances in the design, preparation and applications of innovative cellulose-based hydrogels in controlled drug delivery.  相似文献   
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Salecan is a microbial polysaccharide suitable to obtain hydrogel for biomedical applications due to the excellent hydrophilicity and biocompatibility properties. In this work, Salecan of different concentrations was introduced into polymethacrylic acid (PMAA) in the presence of clay to form novel semi synthetic hydrogel nanocomposites systems and loaded afterwards with doxorubicin (DOX). The physical–chemical characteristics of the nanocomposites systems and their effect on the viability, and morphology of MDBK (Madin–Darby bovine kidney), HT-29 human colorectal adenocarcinoma and Colo 205 human colon adenocarcinoma cell lines were investigated. DOX release from the nanocomposite systems, cell up-take and subsequent effect on cell proliferation was also analyzed. It was found that Salecan concentration determined the swelling behavior, structural parameters and morphological features of the nanocomposite systems. The hydrogen bonds strongly influenced the formation of PMAA–Salecan–clay systems, each component bringing its own contribution, thus demonstrating the achievement of an advanced crosslinked network and a more compacted hydrogel nanocomposite morphology. All the synthesized nanocomposites had negligible toxicity to normal MDBK cells and chemoresistent HT-29 cell line, whereas in the case of Colo 205 cells a decrease by 40% of the cell viability was obtained for the sample containing the highest amount of Salecan. This effect was correlated with the lowest pore size distribution leading to highest available specific surface area and entrapped amount of DOX which was further released from the nanocomposite sample. Corroborating all the data it can be suggested that the synthesized nanocomposites with Salecan and clay could be good candidates as vehicles for chemotherapeutic agents.  相似文献   
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Background/Aims: Central pancreatectomy is a pancreas- sparing alternative to standard pancreatic resections in selected cases. Although associated with high morbidity, the risk factors for surgical complications of this procedure are not yet defined. Methodology: The clinicopathological and perioperative data of 24 patients who underwent central pancreatectomies (2002-2010) were correlated with surgical complications. Results: The overall morbidity rate was 54% (pancreatic fistula, 40%). In a univariate analysis, age over 40 years, body mass index ≥30kg/m2, smoking and American Society of Anesthesiologists III scores were significantly correlated with increased morbidity. In a multivariate analysis, a significant correlation with the development of complications was found for body mass index ≥30kg/m2 and age over 40 years. Conclusions: Certain patient-related factors (older age, obesity and smoking) appear to have a negative impact on early postoperative outcome after central pancreatectomy. For patients with these factors, an alternative distal pancreatectomy should be considered. Central pancreatectomy should be tailored not only to the pathology but also to the patient profile.  相似文献   
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The current study examined the association between alexithymia and coping styles (planning, positive reinterpretation and growth, social‐emotion coping, and denial), and trauma symptoms in a clinical sample of 170 male and female veterans who experienced sexual trauma during military service. Denial was the only coping style positively associated with trauma symptoms, and it mediated the relationship between alexithymia and trauma symptoms. Alexithymia was negatively associated with planning. Likewise, alexithymia was negatively associated with social‐emotional coping and with positive reinterpretation and growth. The results speak to the significant role that alexithymia has in predicting individual coping styles. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
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The two major genes responsible for autosomal dominant polycystic kidney disease and complex tuberous sclerosis are located on chromosome 16 at position 16p13.3, separated by only a few nucleotides. A simultaneous loss of both genes has been termed "the TSC2/PKD1 contiguous gene syndrome". It has been described essentially in young children. We report 2 new cases in French adults, in whom the diagnosis has been made fortuitously on the macroscopic and microscopic examination of the nephrectomy specimen. This diagnosis should be considered for the association of a polycystic kidney disease and numerous angiomyolipomas. It is necessary to set up a specific follow-up of both diseases.  相似文献   
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