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31.
Inhibition of HIV-1 infectivity with curdlan sulfate in vitro 总被引:5,自引:0,他引:5
Y Kaneko O Yoshida R Nakagawa T Yoshida M Date S Ogihara S Shioya Y Matsuzawa N Nagashima Y Irie 《Biochemical pharmacology》1990,39(4):793-797
Polymethoxylated flavones and C-glycosyl derivatives isolated from medicinal plants besides other flavonoid compounds were studied for their influence on lipid peroxidation induced by FeSO4+ cysteine in rat liver microsomes. A number of hydroxyflavones (e.g. luteolin); C-glycosyl-flavones (e.g. orientin); methoxyflavones (e.g. gardenin D) and flavonols (e.g. datiscetin), as well as the flavanol leucocyanidol and the biflavone amentoflavone behaved as inhibitors of non-enzymic lipid peroxidation. Structure-activity relationships were established and it was observed that the structural features for active polyhydroxylated compounds were different from those of polymethoxylated flavones, antiperoxidative flavonoids possessing a high lipophilicity. 相似文献
32.
S Mori N Kondo F Motoyoshi H Kaneko Y Inoue T Orii 《European journal of immunogenetics》1992,19(5):273-285
Six heterogeneous common variable immunodeficiency (CVID) patients were analysed for germ-line DNA, DNA rearrangements, and RNA expressions of immunoglobulin (Ig) gene by Southern or northern blotting using appropriate probes. We detected no polymorphism in neutrophil DNA hybridized to a C mu and a C gamma probe. In three patients, both serum Ig and Ig-bearing cells were scarcely detected, and by northern hybridization methods, neither mu mRNA, gamma mRNA, alpha mRNA nor kappa mRNA was detected. However, one Epstein-Barr virus-transformed B lymphoblastoid cell line (LCL) of these three patients was different from the germ line in the region of JH, C gamma, and C kappa, and expressed mu mRNA at a higher level. The B cell defects of these three patients lay on the B cell maturation stage similar to X-linked agammaglobulinaemia (XLA). In two others among the six CVID patients, serum IgM and IgM-bearing cells were detected to a certain degree, and by northern hybridization, mu mRNA was detected at a lower level, but neither mu mRNA, alpha mRNA, nor kappa mRNA was detected. One LCL of these two patients could express mu mRNA at the normal level. In the last patient, the serum IgM was normal, serum IgG and IgA were somewhat low, Ig-bearing cells were normal, mu mRNA and kappa mRNA were detected at the normal level, and gamma mRNA and alpha mRNA were detected at a lower level. The defect of this patient affected the class switch stage. These results showed that primary B cell defects in CVID occurred at several B cell differentiation stages which could be classified by expression of the Ig gene, and at the degree of clonal diversity in the B cell repertoire. Furthermore, this study provides support for the idea that the CVID defect is related to a more generalized cellular function, such as regulating the proliferation and/or clonal expansion of cells of the B lymphoid lineage. 相似文献
33.
Kazuhiko Suzuki Hiroshi Tanaka Satoshi Kaneko Motoi Nishi Shin Teramoto Susumu Itoh Shosaku Abe 《The Journal of asthma》2003,40(3):243-250
The relation between smoking and risk of asthma has been well-examined; however little attention has been paid to the correlation between smoking and asthma symptoms. The aims of this study were to examine respiratory symptoms in asthmatics with a highly prevalent use of inhaled corticosteroid (ICS) and to assess the effects of smoking and its cessation. A cross-sectional study of pulmonologist-based 3197 asthmatics (men 45.2%, ages 20-97) was performed using a questionnaire about smoking habits, the incidence and frequency of symptoms (sputum, cough and wheezing, night symptoms, and shortness of breath), physical activity interference, and medication. Although 81.4% of the patients used ICS according to the international guideline, 14.9% had activity interference, and daily symptoms remained in 43.3%. At the time of the questionnaire, 21.6% were current and 25.1% were ex-smokers. In multiple logistic regression analysis, the factors of significance (p < 0.0001) were (1) smoking; for all four symptoms, (2) age and duration of asthma; for shortness of breath. Current smokers were at a risk of sputum (age-adjusted odds ratio 2.32 [95% confidence interval 1.73-3.11]; 2.09 [1.57-2.79]), of cough and wheezing (2.38 [1.81-3.14]; 1.78 [1.35-2.36]), of night symptoms (1.95 [1.41-2.60]; 1.47 [1.09-1.98]), and of shortness of breath (1.70 [1.26-2.28]; 1.30 [0.97-1.75]) in men and women, respectively. These ratios in ex-smokers decreased to the level similar to nonsmokers. Although 81.4% of asthmatic patients used ICS, 43.3% complained of daily respiratory symptoms, especially sputum. It is suggested that the effects of ICS on asthma symptoms may be interfered with by smoking and therefore more emphasis should be placed on cessation of smoking. 相似文献
34.
Norihiro Ishida Koji Hayashi Asuka Hattori Keiichiro Yogo Toru Kimura Tatsuo Takeya 《Journal of bone and mineral research》2006,21(1):48-57
We found that a chemokine receptor gene, CCR1, acts downstream of NFAT2 in RANKL-stimulated RAW264 and bone marrow cells. The upstream regulatory region of CCR1 showed RANKL-dependent and CsA-suppressible promoter activity. Downregulation of the expression and function of CCR1 suppressed cell migration. INTRODUCTION: We previously reported that the expression of NFAT2 induced by RANKL is a key process for progression to multinucleated cells in an in vitro osteoclastogenesis system. Identifying the target genes of NFAT2 would thus be informative about the differentiation process. We focused here on chemokine and chemokine receptor genes that act downstream of NFAT2 in RAW264 cells as well as osteoclast precursors prepared from bone marrow cells. MATERIALS AND METHODS: RAW264 mouse monocyte/macrophage line cells were cultured with or without cyclosporin A (CsA) in the presence of RANKL or glutathione S-transferase (GST). Osteoclast precursors were prepared from bone marrow cells. RANKL-inducible and CsA-suppressible genes were searched for by microarray analysis, and expression was confirmed by quantitative RT-PCR. Promoter activity was measured by luciferase gene reporter assay. Short interfering (si)RNA for CCR1 was introduced in RAW264 cells. Cell migration activity was examined using a Boyden chamber assay. RESULTS AND CONCLUSIONS: We identified the chemokine receptor gene CCR1 as a gene showing significant differential expression profiles in osteoclastogenesis in the presence versus the absence of CsA, an inhibitor of NFAT. This property was unique to CCR1 among the chemokine and chemokine receptor genes examined in both RAW264 and bone marrow cells. The upstream regulatory region was isolated from CCR1, and its RANKL-dependent and CsA-suppressible promoter activity was confirmed. The functional significance of CCR1 was assessed by monitoring the migration of cells in a transwell migration assay, and this activity was abolished when either CsA- or CCR1 siRNA-treated cells were used. Moreover, treatment with a Galpha inhibitor pertussis toxin (PTX) or methiolynated-regulated on activation, normal T cells expressed and secreted (Met-RANTES), an antagonist of CCR1, suppressed multinucleated cell formation in the bone marrow cell system. Together, these results suggest that the CCR1 signaling cascade is under the control of NFAT2 and seems to enhance the migration of differentiating osteoclasts. 相似文献
35.
Magnesium deficiency in pregnant women is frequently seen because of inadequate or low intake of magnesium. Magnesium deficiency during pregnancy can induce not only maternal and fetal nutritional problems, but also consequences that might last in offspring throughout life. Many epidemiological studies have shown that restricted fetal growth, i.e. intrauterine growth retardation (IUGR), is associated with an increased risk of insulin resistance in adult life. We previously postulated that the intracellular magnesium of cord blood platelets is lower in the small for gestational age group than in the appropriate for gestational age group, suggesting that intrauterine magnesium deficiency may result in IUGR. Taken together, intrauterine magnesium deficiency in the fetus may lead to or program the insulin resistance after birth. We hypothesize that intrauterine magnesium deficiency may induce a metabolic syndrome in later life. Prospective studies will further clarify whether infants with IUGR induced by magnesium deficiency are at higher risk for metabolic syndromes in childhood or adulthood. 相似文献
36.
37.
We report a rare case of a 54-year-old woman with an interhemispheric epithelial cyst. This will be the first report of an interhemispheric epithelial cyst without callosal agenesis. A partial excision of the cyst wall has led to her recovery with no evidence of recurrence. Ultrastructural studies suggest that the cyst was derived from the primitive neuroepithelium. We discuss the pathogenesis of the interhemispheric epithelial cyst. 相似文献
38.
T Matsunaga N Maseki Y Kaneko K Sampi T Tsuchimochi M Sakurai M Hattori S Takayama 《[Rinshō ketsueki] The Japanese journal of clinical hematology》1992,33(6):829-833
The authors report six cases of non-Hodgkin's lymphoma (NHL) (3B-cell type, one T-cell type, one non-T non-B cell type, one unclassified type) occurring subsequently to autoimmune diseases. The patients were females aged 43 to 70 (median 61). Rheumatoid arthritis was most frequent as the preceding autoimmune disease, and the intervals from the onset of an autoimmune disease to that of NHL were 10 to 36 years (median 20). Polyclonal hypergammaglobulinemia was seen in 4 cases, lymphocytopenia in 3 cases, and conversion to negative PPD reaction in 2 cases. Only one patient had been given corticosteroids, and immunosuppressive agents may not contribute much to the development of lymphoma in patients with autoimmune diseases. 相似文献
39.
K Hashizume H Nukui T Horikoshi M Kaneko A Fukamachi 《Neurologia medico-chirurgica》1992,32(9):693-697
A ruptured giant aneurysm of the azygos anterior cerebral artery (ACA) associated with an acute subdural hematoma (SDH) occurred in a 67-year-old male with two episodes of sudden severe headache and transient loss of consciousness. Neurologically, he had mild weakness of the left lower extremity. Computed tomography showed an elliptical heterogeneous hyperdense mass in the interhemispheric fissure in front of the corpus callosum and an acute SDH on the right. Angiography disclosed a giant aneurysm (2.8 x 2.0 cm) at the distal end of the azygos ACA. Removal of the SDH and aneurysmal neck clipping achieved a good outcome. Successive small bleedings may allow the aneurysmal dome to develop adhesions to the arachnoid membrane, and the final rupture will occur into the subdural space, resulting in a SDH. 相似文献
40.
Glutaminase has been considered to be a synthesizing enzyme of transmitter glutamate in pyramidal neurons of the cerebral cortex. In the present study, an attempt was made to examine with a double immunofluorescence method whether or not nonpyramidal neurons of the cerebral cortex are immunoreactive for glutaminase. Glutaminase was stained with mouse anti-glutaminase IgM and FITC-labeled anti-[mouse IgM] antibody. In the same section, parvalbumin (PA), calbindin (CB), choline acetyltransferase (CAT), vasoactive intestinal polypeptide (VIP), corticotropin releasing factor (CRF), cholecystokinin (CCK), somatostatin (SS), or neuropeptide Y (NPY) was visualized as a marker for nonpyramidal neurons with an antibody to each substance, biotinylated secondary antibody and Texas Red-labeled avidin. Virtually no glutaminase immunoreactivity was seen in PA-, CB-, CAT-, VIP-, CRF-, CCK-, SS-, or NPY-immunoreactive neuronal perikarya in the neocortex and mesocortex (cingulate and retrosplenial cortices), although it was detected in a few PA-, CB-, VIP-, CCK-, SS-, or NPY-immunoreactive nonpyramidal neurons in the piriform, entorhinal, and hippocampal cortices. PA- and CB-positive neurons have been reported to constitute the major population of GABAergic neurons in the cerebral cortex. Thus, the present results, together with the previous reports, suggest that most GABAergic, cholinergic and peptidergic nonpyramidal neurons in the neo- and mesocortex do not contain glutaminase. 相似文献