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121.
The role cardiac autonomic neuropathy (CAN) plays in diabetes is not well known. The aim of this study was to identify the factors involved in CAN in diabetic patients. One hundred patients, 44 insulin-dependent (IDDM) and 56 non-insulin-dependent (NIDDM), were investigated, using five standard tests. Three of these tests were for parasympathetic control (cardiac response to the lying-to-standing, deep breathing, and Valsalva tests), and the other two measured sympathetic control (testing for orthostatic hypotension and evaluating heart and blood pressure response to the handgrip test). Results were compared to those found in a series of 40 healthy volunteers. An age-adjusted comparison with the controls, showed that 34 patients had one abnormal parasympathetic test, 23 had two, and 6 patients had three. Cardiac parasympathetic neuropathy was thus present in 63% of the patients. The handgrip test was completed by 84 diabetic patients. There was evidence of orthostatic hypotension and/or an abnormal cardiac response to the handgrip in 15 of these patients, who all had a parasympathetic abnormality as well. There was no significant association between the type of diabetes and the presence of CAN. The duration of diabetes was significantly longer in patients with CAN (9.3 +/- 0.9 years) (p < 0.01) than in those with all three parasympathetic tests normal (5.8 +/- 0.9 years) (p < 0.01). The HbA1c level was also higher in patients with CAN than in those with three normal parasympathetic tests (9.95 +/- 0.35% versus 8.17 +/- 0.42%, p < 0.005). There was a significant association between the presence of retinopathy, observed by angiofluorography, and the presence of peripheral neuropathy confirmed by the electrophysiological investigation and the presence of CAN (p < 0.001). However, more than half the patients without retinopathy or nephropathy had CAN, and 11 of the 31 patients with a normal electrophysiological investigation also had CAN. Eighteen patients (6 IDDM) without retinopathy and nephropathy, who had been diabetic for less than 2 years, also had CAN. This study shows that CAN occurs early and is frequently found in a population of unselected diabetic patients. Metabolic factors may play an important role in its occurrence. CAN is significantly associated with the presence of retinopathy, which suggests that an impairment of autonomic peripheral blood flow control might be a contributing factor in the formation of microvascular lesions.  相似文献   
122.
Heme oxygenase catalyzes the oxidation of heme to biliverdin and carbon monoxide. The gene encoding the truncated soluble rat heme oxygenase-1 (Metl-Pro267) was cloned. The enzyme protein was expressed in E. coli JM109 and purified to homogeneity. The molecular weight of the recombinant enzyme was 30 kDa as assessed by SDS-polyacrylamide gel electrophoresis. From a 3-L culture, about 90 mg of the purified enzyme was routinely obtained. The dependency of the heme oxygenase reaction catalyzed by the soluble enzyme on the NADPH-cytochrome P-450 reductase concentrations and the effect of catalase on the reaction were examined to compare with the purified membrane-bound form of heme oxygenase-1 (Yoshida and Kikuchi, 1978b). The activity of the soluble enzyme was inhibited at high concentrations of NADPH-cytochrome P-450 reductase and the inhibition was not alleviated by addition of catalase unlike the membrane-bound form. The ferric iron of the heme-heme oxygenase complex was in a typical high spin state at acidic to neutral pH (pH 6.5-7.0) but conversion to low spin state was observed at basic pH (pH 9-10). The heme bound to heme oxygenase was converted to biliverdin at a stoichiometric ratio of unity in the presence of NADPH-cytochrome P-450 reductase system. During the heme degradation of the heme-heme oxygenase complex under atmospheric oxygen, several intermediates, that is, oxygenated heme and verdoheme, were spectrally discriminated.  相似文献   
123.
124.
In an attempt to clarify the role of macrophages and their mediators during regeneration of the liver, the difference of liver regeneration among C3H/HeN (LPS-responsive strain) and C3H/HeJ (LPS-resistant strain) mice was investigated. After a 67% partial hepatectomy, an increase in the weight of regenerating liver was significantly delayed in the C3H/HeJ mice, as compared with C3H/HeN mice. The number of hepatocytes labeled with antibody against PCNA reached maximum levels 48 hr after partial hepatectomy, but the PCNA labeling index in C3H/HeJ mice was 20% less than that for C3H/HeN mice. In addition, TNF-alpha activities in serum were enhanced shortly after partial hepatectomy in C3H/HeN strain mice, but were not increased in C3H/HeJ strain mice. Serum IL-6 levels were markedly enhanced in both C3H/HeN and C3H/HeJ mice, but a bimodial peak (14 and 48 hr after partial hepatectomy) was demonstrated in C3H/HeN mice, in contrast to a single peak (at 24 hr) in C3H/HeJ mice. Suppression of Kupffer cells by previous administration of gadolinium chloride in C3H/HeN mice reduced the increase in both serum TNF-alpha and IL-6 concentrations, reduced PCNA labeling index of hepatocytes by 20%, and disturbed the regeneration of the liver. Previous administration of antibody against TNF-alpha reduced the PCNA labeling index of hepatocytes by 20% after partial hepatectomy in C3H/HeN strain mice. These results suggest that LPS-responsive macrophages in the liver and their mediators, especially TNF-alpha, could partly play a role in liver regeneration.  相似文献   
125.
126.
Nano-effect on solid electrolytes that appears as a conductivity enhancement is expected as a way to develop or improve practical solid ionic devices, such as solid oxide fuel cells. Interfaces play a major role in the enhanced conductivity. Using nanocrystals (NCs) as the starting material, the nanostructured materials containing many interfaces, i.e., grain boundaries, can be simply made by forming the NCs with successive sintering without grain growth. The past decade has seen significant advances in the syntheses of solid electrolyte NCs and understanding the nano-effects on the ionic conductivity. In the present paper, the syntheses of zirconia- and ceria-based NCs, which are important constituent materials of solid oxide fuel cells, and their grain size-dependent conductivity due to the nano-effect are briefly reviewed.  相似文献   
127.
Ternary zincblende-derived I–III–VI2 chalcogenide and II–IV–V2 pnictide semiconductors have been widely studied and some have been put to practical use. In contrast to the extensive research on these semiconductors, previous studies into ternary I–III–O2 oxide semiconductors with a wurtzite-derived β-NaFeO2 structure are limited. Wurtzite-derived β-LiGaO2 and β-AgGaO2 form alloys with ZnO and the band gap of ZnO can be controlled to include the visible and ultraviolet regions. β-CuGaO2, which has a direct band gap of 1.47 eV, has been proposed for use as a light absorber in thin film solar cells. These ternary oxides may thus allow new applications for oxide semiconductors. However, information about wurtzite-derived ternary I–III–O2 semiconductors is still limited. In this paper we review previous studies on β-LiGaO2, β-AgGaO2 and β-CuGaO2 to determine guiding principles for the development of wurtzite-derived I–III–O2 semiconductors.  相似文献   
128.
The current treatments for chronic hepatitis C virus (HCV) genotype 1 infection are combinations of direct-acting antivirals, and faldaprevir is one of the new generation of HCV NS3/4A protease inhibitors. At the end of 2013, the US Food and Drug Administration (FDA) approved the HCV NS3/4A protease inhibitor simeprevir and the HCV NS5B polymerase inhibitor sofosbuvir. Simeprevir or sofosbuvir in combination with pegylated interferon and ribavirin are available for clinical use. Faldaprevir, another HCV NS3/4A protease inhibitor that also has fewer adverse events than telaprevir or boceprevir, is under development. Of interest, faldaprevir in combination with pegylated interferon and ribavirin, and interferon-free treatment with faldaprevir in combination with deleobuvir plus ribavirin provides high sustained virological response rates for HCV genotype 1 infection. The aim of this article is to review these data concerning faldaprevir. Faldaprevir in combination with pegylated interferon and ribavirin treatment appears to be associated with fewer adverse events than telaprevir or boceprevir in combination with pegylated interferon and ribavirin, and may be one of the therapeutic options for treatment-naive patients with HCV genotype 1. The interferon-free combination of faldaprevir and deleobuvir with ribavirin was effective for HCV genotype 1 infection and may hold promise for interferon-ineligible and interferon-intolerant patients.  相似文献   
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