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31.
Tri-n-butyltin (TBT), one of environmental pollutants accumulated in mollusks, at nanomolar concentrations decreases cellular content of glutathione (GSH), suggesting that TBT increases cell vulnerability to oxidative stress because GSH has a role in catabolizing hydrogen peroxide (H(2)O(2)). In order to examine this possibility, the effect of tri-n-butyltin chloride (TBTCl) on rat thymocytes suffering from oxidative stress induced by H(2)O(2) was examined using a flow cytometer with four fluorescent probes; ethidium bromide, 2',7'-dichlorofluorescin diacetate, 5-chloromethylfluorescein diacetate and annexin-V-FITC. TBTCl at concentrations ranging from 100 nM to 1 μM attenuated H(2)O(2)-induced decrease in cell viability in a dose-dependent manner. It was unlikely that TBTCl reduced H(2)O(2)-induced oxidative stress because TBTCl failed to affect H(2)O(2)-induced oxidation of intracellular molecule (2',7'-dichlorofluorescin) and H(2)O(2)-induced decrease in cellular content of GSH. Results suggest that TBTCl may inhibit the pathway of cell death induced by H(2)O(2) or that TBTCl may induce a protective substance against the oxidative stress produced by H(2)O(2).  相似文献   
32.
BACKGROUND/AIMS: Platelet-derived endothelial cell growth factor (PD-ECGF) is one of the angiogenic factors. The aim of this study was to examine the PD-ECGF concentrations in hepatocellular carcinoma, background liver, and normal liver tissues, and to elucidate their significance on clinicopathological outcomes. METHODOLOGY: The concentration of PD-ECGF in the tissue extract was determined by enzyme-linked immunosorbent assay. RESULTS: PD-ECGF concentrations were significantly higher in hepatocellular carcinoma and background liver tissues compared with normal control liver (p = 0.003, p = 0.001, respectively). PD-ECGF concentrations in hepatocellular carcinoma tissues were positively correlated with intratumoral arteriole densities (r = 0.667, p = 0.009), and were higher in less differentiated carcinomas (p = 0.039). However, tumor PD-ECGF concentration did not affect the patients' disease-free survival rates. Those in the background liver tissues were positively correlated with histological activity index scores (r = 0.650, p = 0.001) and serum alanine aminotransferase levels (r = 0.0452, p = 0.035). CONCLUSIONS: PD-ECGF is up-regulated in hepatocellular carcinoma and the corresponding hepatitis liver. The PD-ECGF concentrations in hepatocellular carcinoma correlated positively with microvessel density, lower differentiation, yet not with patients' prognosis. The concentrations of PD-ECGF in the corresponding hepatitis liver correlated positively with the degree of active hepatitis.  相似文献   
33.
Angiotensin II (Ang II) plays a pivotal role in cardiovascular remodeling leading to hypertension, myocardial infarction, and stroke. Pitavastatin, an HMG-CoA reductase inihibitor, is known to have pleiotropic actions against the development of cardiovascular remodeling. The objectives of this study were to clarify the beneficial effects as well as the mechanism of action of pitavastatin against Ang II-induced organ damage. C57BL6/J mice at 10 weeks of age were infused with Ang II for 2 weeks and were simultaneously administered pitavastatin or a vehicle. Pitavastatin treatment improved Ang II-induced left ventricular hypertrophy and diastolic dysfunction and attenuated enhancement of cardiac fibrosis, cardiomyocyte hypertrophy, coronary perivascular fibrosis, and medial thickening. Ang II-induced oxidative stress, cardiac TGFbeta-1 expression, and Smad 2/3 phosphorylation were all attenuated by pitavastatin treatment. Pitavastatin also reduced Ang II-induced cardiac remodeling and diastolic dysfunction in eNOS-/- mice as in wild-type mice. In eNOS-/- mice, the Ang II-induced cardiac oxidative stress and TGF-beta-Smad 2/3 signaling pathway were enhanced, and pitavastatin treatment attenuated the enhanced oxidative stress and the signaling pathway. Moreover, pitavastatin treatment reduced the high mortality rate and improved renal insufficiency in Ang II-treated eNOS-/- mice, with suppression of glomerular oxidative stress and TGF-beta-Smad 2/3 signaling pathway. In conclusion, pitavastatin exerts eNOS-independent protective actions against Ang II-induced cardiovascular remodeling and renal insufficiency through inhibition of the TGF-beta-Smad 2/3 signaling pathway by suppression of oxidative stress.  相似文献   
34.
Summary 1255 cases of leukemia-lymphoma were tested between 1972 and 1984 by multiple marker analysis. Routine leukemia phenotyping was performed using standard morphological and cytochemical techniques in combination with clinical and histo-pathological information; the main emphasis was put on immunological surface marker analysis using erythrocyte rosette assays, TdT and a large panel of poly- and monoclonal antibody tests. The 1255 cases were divided into these major types and subtypes: 349 cases of ALL and related immature T- and Burkitt-lymphomas (cALL, pre B-ALL, B-ALL and Burkitt-lymphomas, T-ALL and immature, mostly leukemic T-lymphomas, Null-ALL), 454 cases of mature T- and B-cell malignancies (T-CLL, mycosis fungoides, Sezary-syndrome, T-lymphomas, B-CLL, hairy cell leukemia, multiple myeloma, B-lymphomas), 263 cases of acute myeloid leukemias (AML, AMMoL/AMoL), 182 cases of chronic myeloid leukemias (CML in chronic phase, CMoL, CML in blast crisis), 6 cases of erythroleukemia and 1 case of megakaryoblastic leukemia. A simplified classification scheme which has been used in our laboratories is presented. Phenotyping is of diagnostic, prognostic and therapeutic relevance, most evidently for patients with ALL. Routine leukemia phenotyping should be performed with highly standardized techniques and reagents and by combining information from several fields in the multiple marker analysis. New areas of leukemia research might become very useful for the routine procedure of phenotyping.Abbreviations ALL acute lymphoblastic leukemia - AML acute myeloblastic leukemia - AMMoL acute myelomonoblastic leukemia - AMoL acute monoblastic leukemia - cALL common ALL - CLL chronic lymphocytic leukemia - CML chronic myelocytic leukemia - CML-BC CML in blastic crisis - CMoL chronic monocytic leukemia  相似文献   
35.
Well‐differentiated papillary mesothelioma (WDPM) is a distinct subtype of mesothelial tumor from diffuse malignant mesothelioma (DMM), with an uncertain malignant potential. The relationship between WDPM and DMM, with regard to the ability of the former to develop into the latter, is also unknown. A 58‐year‐old woman, diagnosed with a rectal carcinoid tumor, underwent removal of the lymph nodes via the abdomen in 2004. A large number of white miliary nodules were identified on the mesentery and peritoneum, which were histologically diagnosed as WDPM. No further therapy was administered, but the patient was followed‐up using imaging methods. Seven years later, an abdominal wall mass was discovered using positron emission tomography‐computed tomography, and a laparotomy biopsy was performed. DMM was diagnosed, because mesothelioma with extended invasion had been histologically identified. Mesothelioma similar to papillary proliferation was present on the outer layer of the peritoneum, and an infiltrating lesion with continuous restiform or solid‐like structures was noted. WDPM was believed to have undergone malignant transformation. Compared to DMM, WDPM has a good prognosis and is considered a benign or borderline neoplasm. Our findings suggest that WDPM does have malignant potential, however, because histological findings indicated a malignant transformation of WDPM to DMM.  相似文献   
36.
IntroductionThe features of pneumonia in children with neurologic impairment (NI) resemble those of healthcare-associated pneumonia is defined as pneumonia occurring in the community associated with healthcare risk factors. There are currently no guidelines for the treatment of pneumonia in children with NI. Here, we assessed whether the guidelines applicable for treating pneumonia in adults could be applied to children with NI.MethodsBetween 2008 and 2019, we enrolled children with NI who developed pneumonia and were treated in the pediatric ward of Kawasaki Medical School Hospital. We evaluated patient characteristics, the frequency of isolation of multidrug-resistant (MDR) pathogens, and clinical outcomes.ResultsMDR pathogens were more frequently isolated from patients receiving tube feeding (TF) and/or with tracheostomy than from patients without these risk factors. Other risk factors, including a history of antibiotic therapy and methicillin-resistant Staphylococcus aureus isolation, recent hospitalization, residence in a nursing home or extended care facility, and low-dose, long-term macrolide therapy, did not significantly affect the frequency of MDR pathogen isolation. In patients receiving TF and/or with tracheostomy, treatment success was achieved in all cases treated with broad-spectrum antibiotics and 72.2% of cases treated with non-broad-spectrum antibiotics (P = 0.007). Conversely, among patients without these risk factors, no such difference was observed.ConclusionsOur findings indicate that the guideline to select antibiotics for treating pneumonia in children with NI should be simpler and more useful than the current guidelines for adult pneumonia, based on risk factor assessment for MDR pathogens.  相似文献   
37.
Evaluation of mitral flow dynamics during exercise is critically important in patients who receive percutaneous transvenous mitral commissurotomy (PTMC) because limited mitral flow during exercise provokes hemodynamic deterioration and involves cardiogenic symptoms in patients with mitral stenosis. To examine mitral flow dynamics during exercise, we applied continuous wave Doppler technique in 20 patients with mitral stenosis. Exercise Doppler study was performed 2 days before and 5 days after PTMC. PTMC increased mitral valve area from 1.0 +/- 0.3 (mean +/- SD) to 1.9 +/- 0.5 cm2 and decreased mean transmitral pressure gradient from 8 +/- 2 to 4 +/- 1 mm Hg at rest. Moreover, PTMC decreased mean transmitral pressure gradient from 21 +/- 6 to 11 +/- 4 mm Hg at submaximal exercise. The extent of an increase in mitral valve area by PTMC correlated with a decrease in the mean transmitral pressure gradient at the submaximal exercise (r = -0.76, p less than 0.01) and that at rest (r = -0.52, p less than 0.05). Heart rate after PTMC during exercise was significantly lower than that before PTMC, indicating that the compensatory mechanism (tachycardia) to increase cardiac output during exercise is less necessary after PTMC. Thus, we conclude that the mitral flow dynamics during exercise is improved, as well as the resting mitral flow dynamics 5 days after PTMC, and that exercise Doppler study enabled us to make a noninvasive evaluation of the mitral flow dynamics in patients who receive PTMC.  相似文献   
38.
Obesity is associated with health consequences, and thyroid dysfunction may be an adaption to the increased energy expenditure in obesity. With the rising prevalence of obesity in childhood, the prevalence of metabolic syndrome may also increase. In the current study, we have shown gender differences in the association of thyroid hormones with obesity, and attempted to elucidate the relationship between thyroid hormones and anthropometric parameters and biochemical data in obese Japanese children. We analyzed anthropometric measurements, blood pressure, body composition, thyroid hormones, and lipid profiles in 283 obese children. The association between thyroid hormones and several parameters differed by gender. The free T3 to free T4 ratio (fT3/fT4) in boys was negatively associated with the quantitative insulin sensitivity check index, whereas in girls, thyroid-stimulating hormone levels were positively correlated with levels of glucose, diastolic blood pressure, and non-high density lipoprotein-cholesterol, and fT3/fT4 was positively correlated with uric acid levels. FT3/fT4 in boys with metabolic syndrome was relatively higher than in those without metabolic syndrome. The cause of gender differences is unknown. Therefore, further studies with larger sample sizes and a long-term follow-up period are needed to address the influence of thyroid hormones on various parameters.  相似文献   
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40.
Lactobacillus (LB) is a gram-positive rod-shaped bacterium that inhabits the oral cavity, gastrointestinal tract, vagina and nasal cavity. Although LB plays a role in the prevention of infections caused by pathogenic bacteria, it causes some critical infectious diseases such as infective endocarditis (IE). IE due to LB is rare; however, early diagnosis and early treatment are important because of its high mortality rate. We report the onset of IE after otologic treatment in a heavy drinker of alcohol, the second case of IE due to LB in Japan.  相似文献   
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