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991.
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The human DNA mismatch repair (hMMR) system plays an important role in reducing mutation and maintaining genomic stability. The MMR system in human cells is composed of at least six genes (hMSH2, hMLH1, hMSH3, hPMS1, hPMS2 and GTBP/hMSH6). In particular, hMSH2 and hMLH1 are expressed in human cells that are undergoing rapid renewal; their reduced expression has been reported in several tumors. We examined the protein expression pattern of hMSH2 and hMLH1 by immunohistochemistry in 25 ameloblastomas. All ameloblastomas expressed hMSH2 and hMLH1 proteins in the outer layer of epithelial cells. The localization of the staining was exclusively nuclear. These data suggest that the development and progression of these tumors do not depend on a defect in the hMMR system.  相似文献   
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Prostate cancer is the cause of 10% of cancer-related deaths in males in the United States. Metastases are found late in the course of the disease. Metastatic tumors of the oral cavity are rare, representing about 1% of oral tumors and affect jaws much more frequently than soft tissues. Metastatic prostate cancer tends to involve the bones of the axial skeleton. In a recent review, 22 cases of metastases to the jawbones from prostate cancer were found in 390 cases. On the other hand, only 1 case of a metastasis to the oral soft tissues was reported. The authors describe the second case of oral soft tissue metastasis from a prostate cancer. The metastatic lesion was located in the gingiva. Clinicians should be aware of oral soft tissue metastases since they can be the first sign of a not yet diagnosed malignant tumor and they can be very easily confused with several different benign lesions.  相似文献   
995.

Background  

The pathophysiology of cardiovascular disease (CVD) in chronic kidney disease (CKD) remains uncertain, but autonomic dysfunction seems to be involved. The aim of the study is to investigate the cardiac dysautonomia in uremic pediatric individuals through iodine 123 metaiodobenzylguanidine (MIBG) scintigraphy and heart rate variability (HRV) analysis.  相似文献   
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Little is known about the renewal of some groups of cells in dental pulp, and the occurrence and significance of physiological cell death in dental pulp is not yet understood. The possibility of odontoblast disappearance by apoptosis has been proposed, and the presence of apoptotic cells in the rat and human odontoblastic and subodontoblastic layers has been recently described. bcl-2 and p53 are proteins involved in the apoptotic pathway, whereas MIB-1 is a proliferating cell marker. The aim of our study was an immunohistochemical evaluation of bcl-2, p53, and MIB-1 in healthy normal pulps of young human subjects. With bcl-2 immunostaining, some positive cells were found in the odontoblastic and subodontoblastic layers, whereas with MIB-1, only a few stromal cells were positive, and all odontoblasts were consistently negative. No cells were positive to p53. The bcl-2 immunoreactivity of the cells of the odontoblastic and subodontoblastic layers could help to explain the presence of apoptotic cells found in these regions.  相似文献   
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BACKGROUND: The inflammation response is modulated by the elaborated chemokine-chemokine receptor system, which also plays an important role in the development of acute rejection (AR). In this study, we hypothesized that functional genetic variants of some of these modulatory proteins might influence the outcome of AR. METHODS: In a retrospective analysis of a cohort of heart transplanted patients (n=158), we examined eight polymorphisms in four genes implicated in this inflammatory process: RANTES, CCR5, CCR2 and CX3CR1. On the basis of timing occurrence, AR episodes (grade>or= 3A) were classified in "early" (0-3 months posttransplantation; EAR) or "late" outcomes (4-12 months posttransplantation; LAR). RESULTS: The incidences of EAR and LAR were 57.6% and 41%, respectively. Number of LAR episodes was significantly higher in subjects that have already experienced one or more EAR episodes, as compared to subjects that had no EAR (median [25%-75%]: 4 () vs. 1 [1-2.5] respectively; P<0.0001). Statistical univariate analysis showed that none of the mentioned polymorphisms were correlated with EAR or LAR. However, allele-allele association analysis showed that subjects carrying both the CX3CR1 249I allele and CCR5 No-E haplotypes were significantly at lower risk of experiencing EAR (OR=0.2 [95%-CI=0.1-0.5], P=0.001). In contrast subjects carrying both the CCR5 E haplotype and the RANTES -403A allele were significantly at higher risk to develop LAR (OR=8.1 [95%-CI=2.3-28.7], P=0.002). CONCLUSIONS: This exploratory study in heart transplantation suggests that the outcomes of EAR and LAR episodes may be influenced by genetic variant interactions such as "CX3CR1 249I*CCR5 No-E" and "CCR5 E*RANTES -403A."  相似文献   
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