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31.
Oxygen-related free radicals have been suggested as a cause of aging and various diseases, for example, various cancers and rheumatoid arthritis. A radical scavenger as an antioxidant has been sought in foods. Fish sauces are traditional Asian fermented seasonings. Using the luminol chemiluminescence method, the peroxyl radical scavenging capability of fish sauces was examined. From the IC50 values, many fish sauces have been shown to have a strong scavenging capability as well as soy sauces. A scavenging mechanism is also proposed.  相似文献   
32.
An autopsy case of a 19-year-old boy who had shown typical gargoyle features, strictly consistent with mucopolysaccharidosis type II (Hunter's syndrome) was reported. Histologically, cytoplasmic vacuolar change was found In hepatocytes, sinusoidal epithelium of spleen, follicular cells of thyroid, Sertoli cells of testis, chromophobe cell of pituitary and generalized fibroblast-like cells including meninges, cardiac valve and periosteum. The vacuoles consisting of membrane-bound structures with flocculus protein-like material and occasional electron dense bodies on electron microscopy, were considered to be the site of mucopolysaccharide deposition by histochemical analysis. Deposition of lipid material consistent with so-called membranous cytoplasmic body was observed in the neurons of central, peripheral and autonomic nervous system. Hepatosplenomegaly could be explained by cytoplasmic deposition, but the cause of cardiomegaly remained further to be studied. Biochemically hepatic mucopolysaccharide was identified as heparan sulfate, while in the kidney dermatan sulfate and heparan sulfate were detected. The correlation between morphology and biochemistry, and between deposition and degeneration was discussed.  相似文献   
33.
In this study, we isolated and characterized a murine counterpart of the human Arpp (hArpp) gene. Sequence analysis revealed that the murine Arpp (mArpp) gene is almost identical to the Ankrd2 gene, which has recently been isolated as a mouse gene induced in stretched skeletal muscle. The mArpp gene encodes a protein of 332 amino acids that contains four well-conserved ankyrin-repeat domains in the central portion of the protein. The amino acid sequence of mArpp protein (mArpp) is highly homologous to that of mouse cardiac-restricted ankyrin-repeat protein (Carp), which is proposed to be a putative genetic marker for cardiac hypertrophy. Immunohistochemical analysis revealed that mArpp is preferentially expressed in type 1 skeletal muscle fibers, and that mArpp is localized in both the nucleus and the sarcomeric I-band of muscle fibers, suggesting that Arpp may function as a nuclear and sarcomeric protein. Furthermore, mArpp was also expressed in neurons of the cerebellum and cerebrum, the islets of Langerhans in the pancreas, and the esophageal epithelium, suggesting that mArpp may play a functional physiologic role in brain, pancreas, and esophagus as well as in type 1 muscle fibers. Interestingly, although mArpp was localized in both nucleus and cytoplasm in neurons, its localization was restricted to nucleus in pancreas and esophagus, suggesting that intracellular localization of mArpp is regulated in a tissue-specific manner. Furthermore, we found that mArpp- and Carp-expression in skeletal muscle were markedly up-regulated after denervation. Although the elevated expression level of Carp was kept only for two weeks after denervation, that of Arpp was kept at least for 4 weeks, suggesting that mArpp and Carp may play distinct functional roles in denervated skeletal muscle.  相似文献   
34.
Recently, cavitation on the surface of mechanical heart valves has been studied as a cause of fractures occurring in implanted mechanical heart valves. The cause of cavitation in mechanical heart valves was investigated using the 25 mm Medtronic Hall valve and the 23 mm Omnicarbon valve. Closing of these valves in the mitral position was simulated in an electrohydraulic totally artificial heart. Tests were conducted under physiologic pressures at heart rates from 60 to 100 beats per minute with cardiac outputs from 4.8 to 7.7 L/min. The disk closing motion was measured by a laser displacement sensor. A high-speed video camera was used to observe the cavitation bubbles in the mechanical heart valves. The maximum closing velocity of the Omnicarbon valve was faster than that of the Medtronic Hall valve. In both valves, the closing velocity of the leaflet, used as the cavitation threshold, was approximately 1.3-1.5 m/s. In the case of the Medtronic Hall valve, cavitation bubbles were generated by the squeeze flow and by the effects of the venturi and the water hammer. With the Omnicarbon valve, the cavitation bubbles were generated by the squeeze flow and the water hammer. The mechanism leading to the development of cavitation bubbles depended on the valve closing velocity and the valve stop geometry. Most of the cavitation bubbles were observed around the valve stop and were generated by the squeeze flow.  相似文献   
35.
In the present study, we investigated how amyloid beta (Abeta) peptides initially affect neuronal cells in primary cerebral cortical cultures from rat and cynomolgus monkey. In these cultures, complicated interactions between glial and neuronal cells occur; moreover, synaptic interactions similar to those observed in vivo also occur between neuronal cells in these cultures. In this study, we applied low concentrations of Abeta to these well-characterized primary cultures to investigate how Abeta initially affects neurons or astroglial cells. In both rat and monkey cortical cultures, treatment with low concentrations of Abeta failed to drastically change or damage of neurons. Abeta treatment, however, significantly activated astrocytes, resulting in increased apolipoprotein E (ApoE) production. Rat astrocytes were more sensitive to Abeta than monkey astrocytes, and responded to Abeta via a different mechanism. In monkey astrocyte cultures, only direct treatment with Abeta increased ApoE production. In rat astrocyte cultures, however, treatment with conditioned media from cortical cultures grown with Abeta increased ApoE production, indicating that some sort of neuron-derived soluble factor(s) was also involved in activating rat astrocytes. These species differences suggest that monkey cortical cultures would be more useful as an in vitro model system to understand the details of how Abeta accumulates in the human brain, since monkeys are phylogenetically more similar to humans.  相似文献   
36.
Human saliva chromogranin A (CgA) is clinically promising as a psychological stress marker. However, expression of CgA is poorly understood in humans, although salivary gland localization of CgA in other mammals, such as rodents and horses, has been demonstrated. In the present study, we investigated the expression and localization of CgA in the human submandibular gland (HSG) using various methods. CgA was consistently localized in serous and ductal cells in HSG, as detected by immunohistochemistry and in situhybridization. Reactivity was stronger in serous cells than in ductal cells. In addition, strong immunoreactivity for CgA was observed in the saliva matrix of ductal cavities. Western blotting gave one significant immunoreactive band of 68 kDa in the adrenal gland, HSG and saliva. Finally, CgA was detected in secretory granules of serous and ductal cells by immunoelectron microscopy. In conclusion, CgA in humans is produced by HSG and secreted into saliva.  相似文献   
37.
The pathomorphologic features of hypertrophic cardiomyopathy simulating dilated cardiomyopathy in the late stage (HCM-DCM) were compared with those of ordinary hypertrophic cardiomyopathy (HCM). Seven autopsied hearts with HCM-DCM and 11 with HCM were assessed quantitatively using an image analyzer. Unlike HCM, significant left ventricular enlargement and wall thinning were observed in HCM-DCM, and the percentage areas of massive fibrosis and disarray were significantly greater. In HCM-DCM, the disarray was distributed diffusely, whereas massive fibrosis was distributed more intensively in the ventricular septum and anterior wall than in the lateral and posterior wall. Narrowing of intramyocardial small arteries was observed more frequently in HCM-DCM, especially in the ventricular septum and anterior wall, than in HCM. These results suggest that the enlargement and wall thinning of the left ventricle in HCM-DCM are attributable to non-uniform progression of massive fibrosis, which is closely related to small-arterial lesions.  相似文献   
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40.
Copolyesters of 3-hydroxybutyric acid (HB) and 3-hydroxyvaleric acid (HV), P(HB-co-HV), were isolated from Alcaligenes eutrophus and characterized by solution NMR, solid-state 13C CP/MAS NMR, and differential scanning calorimetry. The 13C CP/MAS NMR analysis was compatible with that of a random copolyester of oxy-(1-methyl-3-oxotrimethylene) ( B ) and oxy-(1-ethyl-3-oxotrimethylene) ( V ) units which adopts a regular conformation of a 21 -helix in the solid state throughout a wide range of compositions varying from 0 to 90 mol-% V units. The chain dynamics of P(HB-co-HV) in chloroform was studied by analysis of the 13C and 1H NMR spectra. The carbon-13 spin-lattice relaxation times (T1) and nuclear Overhauser enhancements (NOE) indicated that the copolyester molecules in chloroform are not rigid but rather flexible. The conformational preferences of the copolyester molecules were determined by analysis of the 1H NMR spectra.  相似文献   
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