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51.
Phosphatidylinositol 3 kinases (PI-3 kinases) play a crucial role in the inositol phospholipid signaling pathway. The effect of wortmannin, an inhibitor of PI-3 kinases, on the suppression of thermotolerance development was investigated in the temperature-sensitive cell line tsAF8. When wortmannin was added immediately after the preheating, the thermotolerance was suppressed, with this suppression being dose-dependent from 0.01 to 0.1 microM, but not dose-dependent from 0.1 to 20 microM. Our results suggest that PI-3 kinases might play an important role in thermotolerance development in tsAF8 cells.  相似文献   
52.
Children infected with Chlamydia pneumoniae sometimes experience lower respiratory tract infections such as pneumonia and bronchitis. Although numerous anti-microbial compounds have been reported to be active against the organism, most of them have not been in a clinical trial in infants and children with C. pneumoniae infection. Clarithromycin has been shown to express anti-chlamydial effects in vitro. In this study, we evaluated the clinical anti-C. pneumoniae properties of clarithromycin in children with mainly lower respiratory tract infection. We administered clarithromycin orally to 21 infants and children at a dose of 10-15 mg/kg/day divided into two or three doses for 4-21 days. Clinical symptoms, roentgenographic and laboratory abnormal findings improved. The overall clinical efficacy rate was 85.7% (18 of 21 cases). Administration of clarithromycin was considered to be a suitable treatment for improving lower respiratory infections in infants and children caused by C. pneumoniae.  相似文献   
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BACKGROUND: Non-small cell lung cancer (NSCLC) is resistant to chemotherapy and prognosis of advanced NSCLC patients is considered to be dependent on various prognostic factors. METHODS: We analyzed prognostic factors in patients with advanced NSCLC who had been enrolled in clinical trials conducted by the Okayama Lung Cancer Study Group between 1978 and 1992 using two kinds of multivariate analysis, Cox's multivariate analysis and recursive partitioning and amalgamation (RPA) analysis. RESULTS: The first analysis was performed on 261 patients using 28 variables. Performance status (PS), clinical stage, liver metastasis or serum albumin level was an independent prognostic factor by Cox's analysis. In the second analysis performed on 128 patients having data on neuron specific enolase (NSE), NSE was the most important prognostic factor. Using the RPA method, three subgroups with significantly different survival potentials were defined. Among them, patients with normal serum NSE levels and good PS were found to obtain a markedly favorable prognosis [median survival time (MST) 22.1 months, 3-year survival rate 42.9%], whereas the survival of patients with elevated serum NSE levels and bone metastasis was extremely short (MST 4.7 months, 3-year survival rate 0%). CONCLUSIONS: These results indicate that analysis of prognostic factors including serum levels of NSE is useful for predicting the survival of patients with advanced NSCLC.  相似文献   
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Manganese superoxide dismutase (MnSOD) is a mitochondrial enzyme that converts cytotoxic superoxide radicals into hydrogen peroxide. MnSOD activity is lower in tumor cells, and MnSOD overexpression reportedly ameliorates malignant phenotypes. We established stable MnSOD overexpressing cell lines from a human osteosarcoma cell line, SaOS2, and then investigated the effects of MnSOD overexpression on plating efficiency (PE) and the involvement of reactive oxygen species, including nitric oxide (NO) in those effects. The PE of SaOS2FM(L), a moderate MnSOD overexpression cell line, increased, while that of SaOS2FM(H), a high MnSOD overexpression cell line, decreased. Although we assessed PE using a colony-formation assay, time-lapse microscopic observation revealed that cells attached to the flasks had undergone neither apoptosis nor necrosis. Moreover, MnSOD overexpression did not affect cell doubling time. Therefore, MnSOD overexpression might correlate directly with cellular adhesion's effect on PE changes. When L-buthionine-[S,R]-sulfoximine (BSO) was administered to increase the intracellular concentration of hydrogen peroxide, the PEs of both cell lines decreased, and when hydrogen peroxide was eliminated by the administration of sodium pyruvate, only the PE of SaOS2FM(H) increased. The combination of BSO and NO (NOR4 or isosorbide 5-mononitrate) administration synergistically decreased PE in both cell lines. These findings suggest that changes in cellular adhesion properties correlate with the balance between increased hydrogen peroxide levels and decreased superoxide radical levels. This is the first report to indicate that PE and cellular adhesion properties change bidirectionally according to the levels of MnSOD overexpression: first increasing then decreasing as MnSOD activity increases. Our results indicate that PE changes might be decided by the balance between two cytotoxic compounds (decreased superoxide radical levels and increased hydrogen peroxide levels), and that NO loading and increased hydrogen peroxide synergistically reduce PE and cellular adhesion.  相似文献   
60.
Solvent-induced psychosis has been clinically identified among patients suffering from dependence on volatile solvents and those in psychotic state due to chronic solvent use. To clarify the symptomatological difference between solvent-induced psychosis and schizophrenia, the principal component analysis with VARIMAX rotation was applied to the point and duration estimates of symptoms observed among the solvent group and among the schizophrenic group. There were no significant group differences in age and family history of any psychosis. The study findings are as follows: (1) It is difficult to distinguish two groups based on the prevalence rates of symptoms alone. (2) However, the principal component VARIMAX rotation analysis of the prevalence and duration observing among the solvent group revealed seven factors consisting of "amotivation", "intoxication", "emotional instability", "delusion", "hallucination", "disinhibition" and "memory". The seven factors explained 75.4% of the variance of the symptoms in this group. (3) The same analysis applied to the data from the schizophrenic group showed six factors consisting of "thought progression", "emotional instability", "amotivation (or negative symptoms)", "delusion", "hallucination" and "anxiety". These factors explained 62.9% of the variance in the data of the schizophrenic group. These results support clinical observations the "amotivational syndrome" may be a characteristic feature of patients suffering from solvent-induced psychosis. The results also suggest "solvent psychosis" is a discernible syndrome, and is distinctive from psychotic symptoms of typical schizophrenia.  相似文献   
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