255 research outputs found

    Chemical Vapor-Deposited Amorphous Silicon Nitride

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    Chemical vapor-deposited amorphous Si_3N_4 (CVD-amorphous Si_3N_4) up to 4.2mm in thickness has been prepared from a gaseous mixture of NH_3 and H_2-carried SiCl_4 under various deposition conditions. The formation of the CVD-amorphous Si_3N_4 depended strongly on the deposition temperature, total gas pressure and gas flow rate. The CVD-amorphous Si_3N_4 prepared at 1100-1300℃ does not crystallize by heating at each deposition temperature. Their density and deposition rate are markedly dependent on deposition conditions and have maximum values of 3.00g/cm^3 (94% of the theoretical density of α-Si_3N_4) and 0.36mm/hr, respectively. The Vickers microhardness of the CVD-amorphous Si_3N_4 at room temperature varies between 2200 and 3200kg/mm^2 according to its deposition conditions. The hardness at 1300℃ is 1200~1300 kg/mm^2. The thermal conductivity was 0.010cal/cm/sec/℃ at 20℃ and 0.012cal/cm/sec/℃ at 1300℃. The thermal expansion coefficient at 20~1200℃ is 2.99±0.05/℃. The formation mechanism and the effect of gas flow patterns on the deposition rate of the CVD-amorphous Si_3N_4 are also discussed

    A new therapeutic strategy with istradefylline for postural deformities in Parkinson’s disease

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    Aim of the study. Postural deformities are common in Parkinson’s disease (PD) patients. Several treatment options have been reported, but responses to these treatments appear unpredictable. Istradefylline is a novel drug for PD. Cases of PD patients whose postural deformities were improved after withdrawal of dopamine agonists and initiation of istradefylline are presented. Materials and Methods. Four consecutive patients with postural deformities including antecollis, Pisa syndrome, and camptocormia were recruited and treated with istradefylline in combination with withdrawal of dopamine agonists, which are possible causes of postural deformities. Results. The dopamine agonists were discontinued an average of 26 months after the development of the postural deformities, and istradefylline was initiated an average of 1.3 months after dopamine agonist withdrawal. Three patients with preserved paraspinal muscle volume showed good responses to the treatment regimen at least two months after dopamine agonist withdrawal. Conclusions and clinical Implications. Postural deformities caused by dopamine agonists generally improve less than two weeks after dopamine agonist withdrawal. Given the response time in the present study, the response was unlikely to be caused solely by dopamine agonist withdrawal. Istradefylline can be a potential therapeutic option; however, appropriate selection of patients for treatment with istradefylline is warranted

    Mallory Bodies in Hepatocytes of Alcoholic Liver Disease and Primary Biliary Cirrhosis Contain Nε-(Carboxymethyl)lysine-Modified Cytokeratin, but not those in Hepatic Carcinoma Cells

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    Mallory bodies (MBs) are intracytoplasmic bodies seen in hepatocytes of alcoholic liver disease, primary biliary cirrhosis and hepatocellular carcinoma. However, the mechanism of MB formation has not been fully understood. Proteins could be modified to advanced glycation end products (AGEs) after long-term incubation with reducing sugar. AGEs are known to accumulate in several tissues in aging and age-enhanced disorders. To study the possible glycation process in the formation of MBs, hepatocytes of 80 human liver tissues with MBs were subjected to immunohistochemical analyses with five AGEs, two markers for oxidative stress proteins (OSPs) and four stress-response proteins (SRPs). MBs in hepatocytes of primary biliary cirrhosis and alcoholic liver disease were strongly positive for Nε-(carboxymethyl)lysine (CML) and weakly positive for pyrraline. MBs in hepatocellular carcinomas were negative for both CML and pyrraline. No significant immunoreactivity was detected in MBs for other AGEs, such as Nε-(carboxyethyl)lysine, pentosidine, and 3DG-imidazolone, or for OSPs and SRPs. Stainings for cytokeratin, a major protein component of MBs, and CML were co-localized. Furthermore, immunoblot analysis suggested that cytokeratin of MBs was modified to AGE, since a single protein band detected by a monoclonal anti-CML had a molecular weight identical to cytokeratin. The absence of the CML signal in MBs of hepatocellular carcinoma cells could be explained by scarce content of cytokeratin in carcinoma MBs

    Novel oestrogen receptor beta-selective ligand reduces obesity and depressive-like behaviour in ovariectomized mice

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    Hormonal changes due to menopause can cause various health problems including weight gain and depressive symptoms. Multiple lines of evidence indicate that oestrogen receptors (ERs) play a major role in postmenopausal obesity and depression. However, little is known regarding the ER subtype-specific effects on obesity and depressive symptoms. To delineate potential effects of ER beta activation in postmenopausal women, we investigated the effects of a novel oestrogen receptor beta-selective ligand (C-1) in ovariectomized mice. Uterine weight, depressive behaviour, and weight gain were examined in sham-operated control mice and ovariectomized mice administered placebo, C-1, or 17 beta-oestradiol (E2). Administration of C-1 or E2 reduced body weight gain and depressive-like behaviour in ovariectomized mice, as assessed by the forced swim test. In addition, administration of E2 to ovariectomized mice increased uterine weight, but administration of C-1 did not result in a significant increase in uterine weight. These results suggest that the selective activation of ERa in ovariectomized mice may have protective effects against obesity and depressive-like behaviour without causing an increase in uterine weight. The present findings raise the possibility of the application of ER beta-ligands such as C-1 as a novel treatment for obesity and depression in postmenopausal women.ArticleSCIENTIFIC REPORTS. 7:4663 (2017)journal articl
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