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BACKGROUND: Esophageal carcinoma is common in many countries, and it is characterized by poor prognosis and rapid clinical progression with a high frequency of lymph node metastasis and recurrence. The present study was carried out to evaluate the correlation between vascular endothelial cell marker (CD34), matrix metalloproteinase type 9 (MMP9), and DNA content in esophageal carcinoma. METHODS: A total of 38 patients were classified with histopathologic examination as 8 cases with adenocarcinoma, 24 cases with squamous cell carcinoma, and the last 6 cases with undifferentiated carcinoma. The obtained results of the patient group were compared with the results of 6 cases with proven normal esophageal mucosa as a control group. The samples of patients and controls were subjected to immunohistochemical evaluation of CD34 and MMP9 expression along with DNA index determination using flow cytometry. RESULTS: There was a significant difference between patients and normal cases in DNA index, CD34, and MMP9 pattern (P = 0.003, <0.001, and 0.002, respectively). DNA index was positively correlated with MMP9 (r = 0.574, P < 0.001) and with CD34 (r = 0.562, P < 0.001). MMP9 was correlated with CD34 (r = 0.55, P < 0.001). A significant difference was found in both microvessel density and MMP9 expression with respect to tumor grade and stage. The microvessel density in patients with highly positive staining for MMP9 was higher than in those with negative and weak staining for MMP9 (P = 0.002). CONCLUSION: The analysis of DNA content along with detection of CD34 and MMP9 in esophageal cancer can successfully differentiate the different pathologic lesions and hence can be used powerfully in disease prognosis reflecting valuable information about the aggressiveness and activity of those lesions.  相似文献   
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The oral cavity has sometimes been described as a mirror that reflects a person''s health. Systemic disease such as diabetes or vitamin deficiency may be seen as alterations in the oral mucosa. A variety of external factors cause changes in the oral mucosa, thus altering mucosal structure and function, and promoting oral pathologies (most frequently bacterial, fungal and viral infections). Little is known, however, about immune surveillance mechanisms that involve the oral mucosa.There is no direct contact between specific immune cells in the basal epithelium and microorganisms in the upper layers of the oral mucosa. The author''s hypothesis is that the protective immunity is conveyed through epithelial cells. The present brief review assesses the oral mucosa''s role as the main defense in the interactions between the host and the oral microbial community. A unique model was used to investigate these interactions as the cause of oral disease and to develop new treatments that exploit our knowledge of the host-microorganism relationship.Key Words: Epithelial cells, Fibroblasts, Oral mucosa, Oral pathologies, Tissue engineering  相似文献   
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Renal cell carcinoma (RCC) is the most common renal malignancy in adults and exhibits highly intrinsic and acquired resistance to standard therapeutic strategies. We sought to determine the anti-cancer activity of hydroalcoholic extract of Nigella sativa seeds (NSE) and thymoquinone (TQ). Human renal cell carcinoma (ACHN) and fibroblast L929 cell lines were treated with NSE and TQ, and cytotoxicity was measured using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium (MTT) assay. Cell death pattern was determined by annexin V and propidium iodine (PI)-staining methods. Exposure to NSE, TQ and cisplatin significantly inhibited the growth of ACHN cells and showed significant increase of early apoptotic cells. Normal cells were more resistant to NSE and TQ-induced effects. The present study demonstrates that N. sativa and TQ exert anti-proliferative and pro-apoptotic effects on ACHN cells in a concentration and time-dependent manner, which suggests their potential to be used as a new therapeutic strategy for renal cancers.  相似文献   
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The aim of this study was to evaluate the use of different fixatives on the reliability of histopathological changes in a rabbit model of proliferative vitreoretinopathy (PVR). Twenty eyes from 10 rabbits were divided into four groups. The right eyes were used in two experimental groups (each n = 5), and the left, in two control groups (each n = 5). Using a newly developed scleral incision marker, an oblique scleral incision was standardized in the experimental groups, followed by intravitreal injection of 0.4 ml autologous blood and the left for wound repair for four weeks. Eyes were enucleated at four weeks. The groups differed in the type of used fixative solution (formaldehyde 4% vs. 1% buffered formaldehyde and 1.25% glutaraldehyde). The eyes were evaluated for the development of fibrosis, retinal detachment (RD), and processed for histopathology. Fibrous ingrowth of a variable degree was present in the experimental groups originating from the trauma site. Experimental eyes fixed with formaldehyde 4% had RD extension that was greater than that fixed in formaldehyde/glutaraldehyde mixture; however, the difference did not reach statistical significance (P = 0.15). This difference was not fully explained by the fibrosis which developed. In addition, in control groups, formaldehyde 4% induced a fixative-dependent retinal separation that was absent in eyes fixed with formaldehyde/glutaraldehyde mixture (P = 0.03). In conclusion, a mixture of buffered formaldehyde 1% and glutaraldehyde 1.25% combined with standardized scleral incision resulted in consistent pathological changes. A reliable PVR model is a condition sine qua non to evaluate antifibrotic treatment strategies.  相似文献   
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Background The impact of isolated diastolic dysfunction (IDD) and systolic dysfunction (SD) on health-related quality of life (HRQOL) is unknown. Methods and Results To evaluate HRQOL in patients with IDD and SD under treatment, information on outpatients aged 60-84 years was extracted from the records of 4,500 consecutive individuals who underwent echocardiographic examination at Sado General Hospital. The medical records of these patients were reviewed and a questionnaire, including the Medical Outcome Study Short Form 36, was mailed to 71 IDD and 99 SD patients; answers were obtained from 66 and 91 patients, respectively. The HRQOL of patients with cardiac dysfunction was impaired even when echocardiographic parameters improved with treatment. Patients with IDD showed an impairment of HRQOL similar to those with SD. Compared with males, female patients had a larger and more significant reduction in the physical and mental components of the HRQOL score. These scores correlated positively with exercise capacity in patients with IDD or SD. Conclusions Impaired HRQOL, in both its mental and physical components, is a serious problem for IDD and SD patients under treatment. Because exercise intolerance may underlie the reduced HRQOL, improving exercise capacity could be an important target for managing outpatients with heart failure. (Circ J 2008; 72: 1436 - 1442).  相似文献   
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BACKGROUND: The future burden of heart failure in Japan was projected to 2055 in order to prospectively estimate of the number of these patients. METHODS AND RESULTS: The statistics are based on prevalence data of left ventricular dysfunction (LVD) in Sado City using the Sado Heart Failure Study (2003) and population estimates from the Japanese National Institute of Population and Social Security Research Report (2006). The number of Japanese outpatients with LVD was 979,000 in 2005, and is predicted to increase gradually as the population ages, reaching 1.3 million by 2030. CONCLUSION: LVD is expected to precipitate a future epidemic of heart failure in Japan.  相似文献   
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