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971.
A 49-year-old man suffered from bilateral anterior ischemic optic neuropathy almost simultaneously, and was diagnosed with idiopathic aldosteronism associated with hypertension. Because this patient had multiple organ disorders, multiple cerebral infarctions, and a mild loss of renal function, it was important to treat his primary disease.  相似文献   
972.
Previous studies by our and other groups have shown that microbial products containing more than one epoxide group, including eponemycin, radicicol, depudecin and AGM-1470, exhibit anti-angio-genic activity in an in vivo assay system involving chorioallantoic membranes (CAMs) of growing chick embryos. Based on these findings, rhizoxin, a microbial metabolite that contains two epoxide groups and exhibits anti-tubulin activity, was tested for anti-angiogenic activity in a CAM assay system. Rhizoxin caused dose-dependent inhibition of embryonic angiogenesis, the IDS(1 value being 2 ng (3.2 pmol) per egg. In addition, this compound (2 nig/kg i.p.) significantly suppressed neovascnlarizatlou induced by M5076 mouse tumor cells in a mouse dorsal air sac assay system, compared to the vehicle alone (P<0.05). These results indicate that rhizoxin is a novel inhibitor of angiogenesis, and that it has potential as a new therapeutic agent for cancer.  相似文献   
973.
Two different erythroleukemia cell lines have been established from the splenic lesions of transgenic mice possessing the Friend spleen focus-forming virus (F-SFFV) gp55 gene. One showed a neardiploid karyotype and a temperature-sensitive (ts) p53 mutation, and the other, a hyper-triploid karyotype with double p53 mutations found by single-strand conformation polymorphism (SSCP) analysis. The cell lines both retained No.11 chromosomes on which p53 genes are localized. Another p53 allele in the cell line with the ts-p53 mutation appeared intact in the SSCP analysis of the genomic exon 5. The cells with the ts-mutant p53 gene showed no apparent change with temperature shift in their growth or dimethylsulfoxide-induced differentiation, although the wild-type p53 gene on the other allele was not expressing. This ts-p53val-135 gene made p53-deficient fibroblasts anchorageindependent at 37°C but not at 32°C. This non-virus-producing, mouse erythroleukemia cell line will be useful for the study of mutated p53 function during the induction of erythrodifferentiation or apoptotic change.  相似文献   
974.
The role of hepatocyte steatosis in interferon (IFN) resistance is still unclear, especially in patients infected with hepatitis C virus (HCV) genotype 2a. The present study was conducted in 364 consecutive non-cirrhotic naive patients infected with genotype 2a, who were evaluated for the severity of steatosis and response to IFN monotherapy after a 24-week median duration of therapy. The patients were examined for factors associated with steatosis and treatment efficacy according to the grade of steatosis. Early viral kinetics was also evaluated in 64 patients for predictors of response to therapy. Nine IFN-resistant patients were assessed for the relationship between amino acid sequence of HCV core region/NS5A and severity of steatosis. Multivariate analysis identified two independent factors associated with steatosis; serum ferritin > or =200 microg/l and body mass index > or =25.0 kg/m(2). The sustained virological response rate in patients with high-grade steatosis was significantly lower than in the low-grade group. Study of early viral kinetics showed a significantly lower cumulative HCV-RNA negative rate for the high-grade than low-grade steatosis group. Sequence analysis of HCV core region/NS5A in IFN-resistant patients with or without steatosis failed to identify steatosis-specific amino acid substitutions associated with resistance. This study of HCV genotype 2a suggested that steatosis is associated with excess iron storage, and that it is an important predictor of efficacy of IFN monotherapy. Further large-scale studies are warranted to examine the role of amino acid substitutions on IFN resistance specific for steatosis.  相似文献   
975.
To analyze the effect of human T-cell leukemia virus type I (HTLV-I) on cellular gene expression and its relation to tumorigenesis, two lines of transgenic mice carrying the long terminal repeat (LTR)-env-pX-LTR regions of the HTLV-I genome were produced. The transgene was expressed in many organs, including the brain, salivary gland, spleen, thymus, skin, muscle, and mammary gland. We found that the expression of the c-fos and c-jun genes, but not of thelyn and c-myc genes, was augmented 2- to 20-fold in histologically normal skin and muscle of these mice. The augmentation was tissue specific, suggesting the involvement of a cellular factor in the transgene action. In these mice, a three to seven times higher incidence of tumors was seen as compared with the control mice. These tumors included mesenchymal tumors, such as fibrosarcoma, neurofibroma, and lipoma, and adenocarcinomas of the mammary gland, salivary gland, and lung. The c-fos and c-jun genes were also activated in these tumors. The possible roles of elevated c-fos and c-jun gene expression in tumorigensis are discussed.The abbreviations used are ATL, adult T-cell leukemia; HTLV-I, human T-cell leukemia virus type I; IL-2, interleukin 2; IL-2R, interleukin 2 receptor; IL-6, interleukin 6; LTR, long terminal repeat.  相似文献   
976.
The phenotypic expression of cardiomyopathy is greatly influenced by extrinsic factors other than intrinsic genetic defects, such as environmental stress. Exercise is assumed to be an important extrinsic factor, since sudden death is sometimes seen during exercise in young patients with hypertrophic cardiomyopathy (HCM). However, the long-term effects of mild exercise on phenotypic expression in cardiomyopathy remain unclear. To evaluate the effects of exercise performed during infancy or adolescence in cardiomyopathic patients, cardiomyopathic Syrian hamsters (BIO14.6) were subjected to swimming. BIO14.6 and age-matched congenic normal hamsters (CN) as controls were divided into three groups: sedentary (Sed), and trained during infancy (Inf) and during adolescence (Ado). Histological and biochemical analysis of 41-week-old hamsters revealed that (1) the relative level of beta-myosin heavy chain mRNA was significantly lower in the Inf group than in the Sed and Ado groups of BIO14.6. The level in the Inf group of BIO14.6 was compatible with that in the age-matched Sed group of the CN strain; (2) in BIO14.6, degenerative mitochondrial change in the cardiomyocytes was not seen in the Inf group while it was common in the Sed and Ado groups; (3) calcineurin phosphatase activity in the swimming group in 10-week-old CN was significantly higher than that of the age-matched sedentary group, and was as much as that of the swimming and sedentary groups in 10- and 41-week-old BIO14.6.  相似文献   
977.
ABSTRACT  Fukuyama-type congenital muscular dystrophy (FCMD), Walker-Warburg syndrome (WWS), and muscle-eye-brain (MEB) disease are clinically similar autosomal recessive disorders characterized by congenital muscular dystrophy, lissencephaly, and eye anomalies. Through positional cloning, we identified the gene for FCMD and MEB, which encodes the fukutin protein and the protein 0-linked mannose pi, 2-N-acetylglucosaminy ltransferase (POMGnTl), respectively. Recent studies have revealed that posttranslational modification of oc-dystro-glycan is associated with these congenital muscular dystrophies with brain malformations. In this review Fukuyama-type congenital muscular dystrophy (FCMD), other CMDs with brain malformations, and their relation with a-dystroglycan are discussed.  相似文献   
978.
The role of acyclovir-sensitive herpes simplex virus (HSV) was analyzed in the process of its replacement by a resistant virus in vitro and in vivo in the aspect of acyclovir therapy. The mode of replacement of acyclovir-sensitive HSV with acyclovir-resistant HSV was examined by the passages of acyclovir-sensitive wild type HSV in Vero cells under acyclovir-treatment. The development of resistance was monitored more adequately by counting the number of acyclovir-resistant viruses in 10,000 plaque forming units than by the conventional susceptibility assay. The resistance increased with the proportion of thymidine kinase-deficient (TK(-)) viruses, when the susceptibilities of acyclovir-treated HSV population to 5'-iodo-2'deoxyuridine and phosphonoacetic acid were examined. The increased resistance was due to the increased proportion of acyclovir-resistant virus but not intermediately resistant virus. Infection with mixtures of TK(-) and acyclovir-sensitive strains rendered TK(-) sensitive to acyclovir, and virus yields were reduced to the levels of acyclovir-sensitive virus in Vero cells. Their yield reduction depended on the proportion of acyclovir-sensitive viruses and induction of TK activity. This reduction in virus yields of the mixture of TK(-) and acyclovir-sensitive strains was confirmed by acyclovir treatment in the skin of mice with cutaneous infection. Acyclovir treatment combined with superinfection of acyclovir-sensitive virus delayed the development of herpetic skin lesions due to acyclovir-resistant virus and reduced virus yields in the infected skin. Acyclovir-sensitive virus plays an important role in suppressing the generation and replication of acyclovir-resistant virus during acyclovir therapy.  相似文献   
979.
BACKGROUND: Endometriosis is a multifactorial disease with possible genetic predisposition and involvement of environmental factors in its pathogenesis. Cytokines may play important roles in the pathogenesis of endometriosis. The aim of this study was to investigate whether the interferon-gamma gene (IFNG) CA-repeat and interleukin-4 (IL-4) promoter region (-590C/T) polymorphisms may be responsible in part for genetic susceptibility to endometriosis. METHODS: IFNG CA-repeat and IL-4 -590C/T polymorphisms were determined for 185 patients with endometriosis and 176 healthy fertile women by quantitative genescan technology and PCR-restriction fragment length polymorphism analysis, respectively. Patients with endometriosis were analysed further according to their stage of disease, the presence or absence of chocolate cysts and whether or not their disease was associated with adenomyosis and/or lyomyomata. RESULTS: The global IFNG allele frequencies in the patients with endometriosis were significantly different from those in the control women (chi2 = 12.964, 6 df, P = 0.0436). The difference was due to an increase of the a13 (114 bp) allele in patients with endometriosis (chi2 = 10.222, P = 0.0088, corrected P = 0.0352, odds ratio = 1.48, 95% confidence interval = 1.10-1.98). There were no differences in IL-4 -590C/T genotypes and allele frequencies between control women and all patients with endometriosis or between control women and each subgroup of patients with endometriosis. CONCLUSION: The results suggest that the IFNG CA-repeat polymorphism is associated with susceptibility to endometriosis in a Japanese population.  相似文献   
980.
We examined plasma protein adsorption and platelet adhesion to polysulfone (PSf) flat membranes coated with Pluronic with varying polyethylene oxide (PEO) block length. Adsorption of albumin, globulin and fibrinogen to Pluronic-coated PSf membranes was independent of plasma dilution when concentrations of human blood plasma above 20% were applied. Increasing coating concentrations of aqueous Pluronic solution resulted in decreased protein adsorption by the PSf membranes. Pluronic F68, which was more hydrophilic than Pluronic L62 or L64 and had 80% of PEO content, was the most effective at suppressing the adsorption of plasma proteins and platelet adhesion to PSf membranes. We developed a mixed protein solution containing human albumin, gamma-globulin and fibrinogen to attempt to mimic the competitive and cooperative binding effects found in plasma. Fibrinogen adsorption from plasma could be recapitulated by the mixed protein solution. The number of platelets adhering to the PSf membranes decreased as the coating concentration of Pluronic solution was increased, and platelet adhesion decreased in parallel with fibrinogen adsorption. These results suggest that the bioinert property of PEO segments in the Pluronic, which is ascribed to their high flexibility in aqueous media, suppresses the adsorption of plasma proteins and platelets to the Pluronic-coated PSf membranes.  相似文献   
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