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991.
PURPOSE: It has been reported that the visual outcome of retinal pigment epithelial tear (RPE tear) in the fovea is worse than that of RPE tear sparing the fovea. We report optical coherence tomography (OCT) findings of 3 cases with RPE tear in the fovea who preserved good visual acuity. PATIENTS: All patients had serous retinal pigment epithelial detachment involving the macula. The RPE was torn and rolled RPE was observed in the fovea. In OCT findings, a fovea was observed on the RPE flap, and visual acuity was preserved after RPE tear repair. CONCLUSION: We considered that preservation of good visual acuity was due to the presence of a fovea on the RPE flap. We could precisely analyze the location of the fovea and RPE tear using OCT.  相似文献   
992.
993.
Endothelial cells play important roles in anticoagulant and fibrinolytic systems. Recent studies suggest that increases in ambient particulate matter (PM) levels have been associated with an increase in mortality rate from cardiovascular diseases. We examined the production of heme oxygenase-1 (HO-1) and factors related to the fibrinolytic function by rat heart microvessel endothelial cells exposed to organic extracts of diesel exhaust particles (OE-DEP) and urban fine particles (OE-UFP) to investigate the direct effects of these soluble organic fractions in these PM on the fibrinolytic function of endothelial cells. The cell monolayer exposed to 10 μg/ml OE-DEP produced a larger amount of HO-1 than cells exposed to 10 μg/ml OE-UFP. OE-DEP and OE-UFP exposure reduced plasminogen activator inhibitor-1 (PAI-1) production by the cells but did not affect the production of thrombomodulin, tissue-type plasminogen activator, or urokinase-type plasminogen activator. Increased PAI-1 synthesis in response to treatment with 1.0 ng/ml tumor necrosis factor-α or 0.5 ng/ml transforming growth factor-β1 was reduced by OE-DEP exposure. Suppression of PAI-1 production by OE-DEP exposure was mediated through oxidative stress and was independent of HO-1 activity. These results suggest that exposure to the soluble organic fraction of PM and DEP induced oxidative stress and reduced the PAI-1 production of endothelial cells.  相似文献   
994.
Hypermethylation of ASC/TMS1 is a sputum marker for late-stage lung cancer   总被引:4,自引:0,他引:4  
DNA hypermethylated gene promoter sequences are extremely promising cancer markers. Their use for risk assessment, early diagnosis, or prognosis depends on the timing of this gene change during tumor progression. We studied this for the proapoptotic gene ASC/TMS1 in lung cancer and used the findings to develop a sputum marker. ASC/TMS1 protein levels are reduced in all lung cancer types (30 of 40; 75%) but not in 10 preinvasive lesions. Hypermethylation of ASC/TMS1 is also associated with invasive cancers (41 of 152 or 27.0% of all lung cancer types) with variation in incidence between histopathologic types including 32.1% (26 of 81) of adenocarcinomas, 13.2% (7 of 53) of squamous cell carcinomas, 38.5% (5 of 13) of large-cell carcinomas, and 60% (3 of 5) of small-cell lung cancers. The hypermethylation is particularly correlated with late tumor stages being present in only 14% of stage I but 60% of later-stage tumors. The incidence of ASC/TMS1 hypermethylation in sputum DNA fully mimics the tissue findings being present in only 2% (2 of 85) of high-risk, cancer-free smokers, 15% (3 of 18) of patients with stage I non-small-cell lung cancer (NSCLC), but 41% of patients with stage III NSCLC (18 of 44), including 56% (10 of 18) of those with adenocarcinoma. Importantly, sputum is positive for this marker in 24% (10 of 42) of very high risk, clinically cancer-free individuals previously resected for stage I NSCLC. Thus, hypermethylation of ASC/TMS1 is a marker for late-stage lung cancer and, in sputum, could predict prognosis in patients resected for early-stage disease.  相似文献   
995.
BACKGROUND: We sometimes encounter hepatocellular carcinoma (HCC) with a central scar and a scalloped tumor margin resembling focal nodular hyperplasia (FNH) in macroscopic appearance. The fibrolamellar variant sometimes shows this appearance; however, this type of HCC can be clearly differentiated from fibrolamellar variants on the basis of clinical and histopathological findings. The clinical features of patients with this type of HCC need to be clarified. METHODS: From 1988 to 1999, 1,043 patients with HCC underwent hepatectomy at our institution. Histopathological examinations show that fibrolamellar HCC was not included in the series. We selected HCC with a central scar and a scalloped tumor margin resembling FNH in macroscopic appearance. We refer to such tumors as scalloped HCC. We compared the clinical findings and surgical outcomes between patients with scalloped HCC and patients with simple nodular HCC. RESULTS: Of the 1,043 cases of HCC, 31 (3%) and 571 (55%) were scalloped HCC and simple nodular HCC, respectively. The mean age of the patients with scalloped HCC was 60.7 years, and that of the patients with simple nodular HCC was 62.6 years, without significant difference. The rates of hepatitis C virus infection and liver cirrhosis and serum alpha-fetoprotein levels were significantly lower, and Child-Pugh class and surgical outcomes were significantly better in patients with scalloped HCC than in those with simple nodular HCC. In multivariate analysis, Child-Pugh class (P < 0.001), tumor size (P = 0.046), and gross appearance (P = 0.009) were independent significant prognostic factors. CONCLUSION: HCC with a central scar and a scalloped tumor margin resembling FNH occurs in non-cirrhotic patients in their 60s and is associated with a good surgical outcome.  相似文献   
996.
Post-transplant lymphoproliferative disorder (PTLD) is a complication that can develop after either solid-organ or hematopoietic stem cell transplantation (HSCT). T-cell PTLD is a rare disorder, especially following autologous HSCT. Here we report a case of T-cell PTLD which occurred after autologous peripheral blood stem cell transplantation (PBSCT) for relapsed angioimmunoblastic T-cell lymphoma (AILT). Three months after the transplant, the patient developed fever with elevated plasma Epstein-Barr virus (EBV)-PCR values. The patient subsequently developed pneumonitis, hepatomegaly and marked pancytopenia due to hemophagocytosis. The patient died of multi-organ failure, despite antiviral and steroid pulse therapy. Our post-mortem study confirmed the marked proliferation of EBV-infected T-cells that differed from the original AILT clone and macrophages/histiocytes were observed in the marrow, liver, lymph nodes and lungs. Phagocytosis was most evident in the bone marrow. The patient's AILT remained in complete remission. To the best of our knowledge, this is the first case of fulminant EBV-associated T-cell lymphoproliferative disorder (LPD) following autologous HSCT.  相似文献   
997.
Few epidemiological studies have examined associations between diet and pancreatic cancer in Japan. In the Japan Collaborative Cohort Study for Evaluation of Cancer Risk, we evaluated the relationship between dietary factors, including meat, vegetable, and fruit intake, and the risk of pancreatic cancer deaths. Among the original cohort established between 1988 and 1990, 46,465 men and 64,327 women aged 40-79 yr were followed-up through December 31,1999. During 1,042,608 person-years of follow-up, we documented 300 deaths from pancreatic cancer. A 33-item food-frequency questionnaire was used to assess dietary intake at the baseline survey. Cox proportional-hazards models were used to estimate the relative risks of pancreatic cancer death in relation to the intake frequency of food items. We did not observe an overall association between meat intake and pancreatic cancer risk. Except for a 50% decrease in risk associated with high fruit intake among men, we did not find other significant inverse relationships between vegetable and fruit intake and pancreatic cancer risk. Smoking did not modify the associations with dietary habits. Our study suggested that high consumption of pickles and wild edible plants, mainly bracken, might be related to increased pancreatic cancer risk; however, this finding should be confirmed in other epidemiological studies.  相似文献   
998.
To clarify the carcinogenicity of acetaldehyde when associated with ALDH (aldehyde dehydrogenase) 2 polymorphism, Aldh2 knock-out (Aldh2-/-) mice and their wild type (Aldh2+/+) mice were exposed to two different concentrations of acetaldehyde (125 ppm and 500 ppm) for two weeks. Aldh2-/- mice, which have the same genetic background as C57BL/6J (wild mice) except for the Aldh2 gene, were used as models of humans who lack ALDH2 activity. Urinary 8-hydroxydeoxyguanosine (8-OHdG) and plasma malondialdehyde (MDA) levels were measured as indicators of oxidative DNA damage and lipid peroxidation, respectively. At 125 ppm acetaldehyde exposure for 12 d, urinary 8-OHdG levels in Aldh2+/+ mice did not increase. However, urinary 8-OHdG levels in Aldh2-/- mice were slightly increased by the end of the exposure. On the other hand, plasma MDA levels did not increase in either Aldh2-/- orAldh2+/+ mice. At 500 ppm, urinary 8-OHdG levels in both Aldh2-/- and Aldh2+/+ mice significantly increased after 6 and 12 d, but there was no genetic difference. On the other hand, plasma MDA levels in Aldh2+/+ and Aldh2-/- mice did not increase at either 125 ppm or 500 ppm after two weeks of exposure. In conclusion, it is suspected that DNA was damaged by acetaldehyde inhalation, and that susceptibility to acetaldehyde varies according to Aldh2 genotype.  相似文献   
999.
Equol, a derivative of daidzein produced by enterobacteria, has greater activity as a phyto-oestrogen compared with daidzein. Difructose anhydride III (DFAIII) is a newly manufactured non-digestible disaccharide with unique fermentation properties. The present study evaluated the prebiotic effects of DFAIII on equol production and on plasma cholesterol concentrations related to the changes in equol production. We compared plasma equol concentrations at 10.00 and 18.00 hours and faecal isoflavone excretion in three groups of seven rats (male Wistar-ST strain, 6 weeks old) fed a basal diet or a DFAIII or fructooligosaccharide (15 g/kg diet) diet containing 1 g soya isoflavones/kg diet for 20 d. Equol concentrations in the DFAIII group were higher than in the control and fructooligosaccharides groups, especially in the later phase of the light period (18.00 hours) throughout the experiment. Daizein and genistein concentrations did not change between the diet groups. The faecal ratios of equol:daidzein were very high in all groups, but the ratios were higher in the DFAIII group than the control and fructooligosaccharide groups on day 3, and this tendency continued throughout the experiment. On day 20, the plasma total cholesterol concentration was lowest in the DFAIII group. Additionally, the cholesterol concentrations were inversely correlated to plasma equol concentration in all the rats. In conclusion, DFAIII efficiently enhanced plasma equol concentrations, which may be associated with an increase in equol production and a decrease in equol degradation by enterobacteria. Higher plasma equol concentrations may contribute to the hypocholesterolaemic effect of DFAIII feeding.  相似文献   
1000.
Shift workers have been reported to have an increased risk of some cancers. However, the risk of prostate cancer in shift workers is not known to have been examined previously. This study prospectively examined the association between shift work and risk of prostate cancer incidence among 14,052 working men in Japan enrolled in a large-scale prospective cohort. A baseline survey was conducted between 1988 and 1990. Subjects were asked to indicate the most regular work schedule they had undertaken previously: day work, rotating-shift work, or fixed-night work. During 111,974 person-years, 31 cases of prostate cancer were recorded. The Cox proportional hazards model was used to estimate the risk, with adjustments for age, family history of prostate cancer, study area surveyed, body mass index, smoking, alcohol drinking, job type, physical activity at work, workplace, perceived stress, educational level, and marriage status. Compared with day workers, rotating-shift workers were significantly at risk for prostate cancer (relative risk = 3.0, 95% confidence interval: 1.2, 7.7), whereas fixed-night work was associated with a small and nonsignificant increase in risk. This report is the first known to reveal a significant relation between rotating-shift work and prostate cancer.  相似文献   
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