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61.
62.
M Fukuoka K Yasuda H Fujiwara H Kanzaki T Mori 《Human reproduction (Oxford, England)》1992,7(10):1361-1364
We have reported that the cytokines, interleukin-1 (IL-1), tumour necrosis factor alpha (TNF alpha), and interferon (IFN) alpha, beta, and gamma modulate the steroidogenic function of human luteinized granulosa cells in culture. In the present study we examined the interactions between these cytokines in modulating progesterone and oestradiol production by these cells. Neither IL-1 nor TNF alpha had significant effects on human chorionic gonadotrophin (HCG)-stimulated progesterone production, whereas IFN gamma (1-10 ng/ml) significantly reduced HCG-stimulated progesterone production by 26-37%. Concomitant treatment with IL-1 (1 ng/ml) did not further enhance the inhibitory effect of IFN gamma on HCG-stimulated progesterone production. In contrast, the combination of TNF alpha (1 ng/ml) and IFN gamma (10 ng/ml) acted synergistically to markedly inhibit HCG-stimulated progesterone production by 81%. In addition, IL-1 and TNF alpha, neither of which was effective alone, acted synergistically to reduce significantly HCG-stimulated progesterone production by 30%. The combination of TNF alpha and IFN gamma also markedly inhibited follicle stimulating hormone (FSH)-stimulated oestradiol production by 97%, a significantly greater inhibition than that obtained with either cytokine alone. These results suggest that the cytokines may interact to modulate the steroidogenic function of luteal cells in the developing corpus luteum. 相似文献
63.
Dr. Y. Fukuoka M. Noshiro H. Shindo H. Minamitani M. Ishikawa 《Medical & biological engineering & computing》1997,35(1):33-39
The nonlinearity included in the PCO
2 control system in humans is evaluated using the degree of nonlinearity based on a difference of residuals. An autoregressive
moving average (ARMA) model and neural networks (linear and nonlinear) are employed to model the system, and three types of
network (Jordan, Elman and fully interconnected) are compared. As the Jordan-type linear network cannot approximate respiratory
data accurately, the other two types and the ARMA model are used for the evaluation of the nonlinearity. The results of the
evaluation indicate that the linear assumption for the PCO
2 control system is invalid for three subjects out of seven. In particular, strong nonlinearity was observed for two subjects. 相似文献
64.
Yoshida K Ishigami T Nakazawa I Ohno A Tamura K Fukuoka M Mizushima S Umemura S 《Journal of human genetics》2000,45(5):294-298
Recent evidence suggests that an insertion/deletion (I/D) polymorphism of the gene encoding angiotensin-converting enzyme
(ACE) is associated with myocardial infarction and related cardiovascular diseases. We investigated a possible association
of the ACE polymorphism with essential hypertension in a total of 263 cases/controls from among the elderly (age, over 70 years) and
middle-aged (age between 30 and 60 years) Japanese population. The frequency of the I/I homozygote was significantly higher
in hypertensive subjects than in controls in the elderly age group (33/57 vs 16/46; P = 0.02), but no association was observed in the middle-aged group (25/75 vs 26/85; P = 0.71). Similarly, having at least one insertion allele was associated with essential hypertension in the elderly age group
(83/114 vs 46/92 in controls; P = 0.001), but not in the middle-aged group (78/150 vs 94/170; P = 0.524). These data suggest that genetic variation at the ACE locus may be associated with some determinants for blood pressure in elderly persons, and imply the involvement of the ACE insertion/deletion polymorphism in the etiology of age-related essential hypertension in the Japanese population.
Received: April 18, 2000 / Accepted: July 25, 2000 相似文献
65.
Masanori Hara Daisuke Mase Susumu Inaba Akira Higuchi Takakuni Tanizawa Noriaki Yamanaka Yuichi Sugisaki Yoshikazu Sado Toshio Okada 《Virchows Archiv : an international journal of pathology》1986,408(4):403-419
Summary The immunofluorescent localization of glomerular basement membrane (GBM) antigens was examined in 52 specimens from normal kidneys and in various renal diseases using antisera to human GBM HGBM), IV type collagen (IV Col) and P3 antigen, a rat nephritogen. Anti-HGBM serum normally stained the GBM and the mesangium in a restrictive pattern, anti-IV Col serum stained the GBM and the mesangium in a wider pattern and anti-P3 serum stained only the GBM. In mesangial proliferative glomerulonephritis, including IgA nephropathy pathy and Henoch-Schönlein nephritis, the widened mesangial areas were stained with anti-HGBM and anti-IV Col sera. In membranous nephropathy, the punched-out lesions of thickened GBM were demonstrated with the three antisera in moderate cases and a double linear distribution with fine granulation with anti-HGBM and anti-IV Col sera were revealed in one severe case. In membranoproliferative glomerulonephritis, the expanded mesangium and thickened capillary walls were stained with anti-HGBM and anti-IV Col sera, while the outer line of glomerular capillary walls was only positive with anti-P3 serum. In crescentic glomerulonephritis, the collapsed glomerular tufts were stained normally with anti-HGBM and anti-P3 sera and weakly with anti-IV Col serum. In diabetic nephropathy, anti-HGBM serum stained the GBM in a double linear distribution without reacting with the expanded mesangium; anti-IV Col serum stained the mesangium and the GBM in a less clear double linear fashion while anti-P3 serum stained the GBM as single line. Thin membrane disease and Alport's syndrome had normal reactivity with all antisera. However, in one case of Alport's syndrome anti-HGBM and anti-P3 sera stained the GBM in a focal and segmental pattern, while normal staining with anti-IV Col serum was found. In lesions with adhesions and crescents the staining was positive for HGBM and IV Col and negative for P3; obsolescent glomeruli were stained with anti-HGBM and anti-P3 sera, and had diminished staining with anti-IV Col serum.The identification of the various structural glomerular antigens is useful in the classification of certain types of glomerular diseases. Further insight into the mechanisms underlying these conditions may be obtained in this way. 相似文献
66.
Imai Kimitoshi; Maeda Michiyuki; Fujiwara Hiroshi; Ueda Masamichi; Fukuoka Masatsune; Takakura Kenji; Kanzaki Hideharu; Mori Takahide 《Molecular human reproduction》1995,1(3):147-154
We developed a mouse monoclonal antibody, S2n8, by immunizingmice i.p. with human decidual cells collected in the first trimesterof pregnancy. By indirect immunofluorescence staining of frozensections, S2n8 was found to react with decidual cells and endometrialstromal cells throughout the menstrual cycle, but not with endometrialglandular cells or with the endometrial surface epithelium.Judging from the fluorescence intensity, the antigen expressionon stromal cells was weak in the proliferative phase, and becamestronger in the secretory phase. Decidual cells in the firsttrimester of pregnancy and decidual cells at term showed strongexpression of this antigen. Indirect immunofluorescence stainingof enzymatically dispersed decidual tissue revealed that theS2n8 antigen was expressed on the decidual cell surface. Flowcytometric analysis of 12 freshly prepared stromal cell-enrichedcell suspensions showed that 74.894.2% (mean ±SD 86.1 ± 6.6%) of the cells carried the antigen. Theexpression of S2n8 antigen on cultured stromal cells was enhancedby the addition of oestradiol and/or progesterone. The antigenicmolecule was purified by immunoaffinity chromatography fromdecidua collected in the first trimester of pregnancy, and themolecular weight was estimated to be 140 kDa. These findingsindicate that the S2n8 antigen is a useful cell surface markerfor stromal cells/decidual cells and is associated with theirdifferentiation. cell surface antigen/decidual cells/endometrial differentiation/endometrial stromal cells/monoclonal antibody 相似文献
67.
Ito MR Terasaki S Kondo E Shiwaku H Fukuoka Y Nose M 《Clinical and experimental immunology》2000,119(2):340-345
MRL/Mp-lpr/lpr (MRL/lpr) mice develop glomerular lesions with regular variations in their histopathological manifestations, similar to those in lupus nephritis. These lesions are mainly either cell-proliferative or wire loop-like and are associated with glomerular deposits of immunoglobulins, most frequently IgG and IgM. We previously established a nephritogenic IgG3-producing hybridoma clone, B1, from an MRL/lpr mouse, which induces only a 'wire loop-like' type of glomerular lesion when injected into SCID mice. Injection of SCID mice with an anti-trinitrophenyl IgM antibody-producing hybridoma clone, Sp6, following injection of the B1 clone, however, resulted in the development of a 'cell-proliferative' type of glomerular lesion, associated with an accumulation of both antibodies in glomeruli. This accumulation occurred even though Sp6 IgM antibodies did not react with B1 IgG3 antibodies and vice versa. A mutant clone of Sp6, T/13microE/3.1, which produces antibodies deficient in C1q binding, produced a similar effect as that of the Sp6 clone, i.e. 'cell-proliferative' lesions. Again the B1 antibodies did not react with T/13microE/3. 1-IgM antibodies and vice versa. We therefore conclude that bystander IgM antibodies contribute to the remodelling of glomerular lesions in situ, following glomerular injury by the nephritogenic antibodies. 相似文献
68.
Recruitment of katanin p60 by phosphorylated NDEL1, an LIS1 interacting protein, is essential for mitotic cell division and neuronal migration 总被引:3,自引:0,他引:3
Toyo-Oka K Sasaki S Yano Y Mori D Kobayashi T Toyoshima YY Tokuoka SM Ishii S Shimizu T Muramatsu M Hiraiwa N Yoshiki A Wynshaw-Boris A Hirotsune S 《Human molecular genetics》2005,14(21):3113-3128
LIS1 is mutated in the human neuronal migration defect lissencephaly and along with NDEL1 (formerly NUDEL) participates in the regulation of cytoplasmic dynein function during neuronal development. Targeted disruption of Ndel1 suggested that NDEL1 could have other molecular targets that regulate microtubule organization for proper neuronal migration. To further understanding the molecular mechanism of LIS1 and lissencephaly, we identified the katanin p60 microtubule-severing protein as an additional molecular target of NDEL1. We demonstrate that phosphorylation of NDEL1 by Cdk5 facilitates interaction between NDEL1 and p60, suggesting that P-NDEL1 regulates the distribution of katanin p60. Abnormal accumulation of p60 in nucleus of Ndel1 null mutants supports an essential role of NDEL1 in p60 regulation. Complete loss of NDEL1 or expression of dominant negative mutants of p60 in migrating neurons results in defective migration and elongation of nuclear-centrosomal distance. Our results suggest that NDEL1 is essential for mitotic cell division and neuronal migration not only via regulation of cytoplasmic dynein function but also by modulation of katanin p60 localization and function. 相似文献
69.
Polyethylene/phospholipid polymer alloy as an alternative to poly(vinylchloride)-based materials 总被引:1,自引:0,他引:1
To develop new biomaterials for making medical devices, polymer alloys composed of a phospholipid polymer, poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC), and polyethylene (PE) were prepared. The PE/PMPC alloy membrane could be obtained by a combination of solution mixing and solvent evaporation methods using xylene and n-butanol mixture as a solvent. Moreover, thermal treatment was applied to improve the mechanical properties of the PE/PMPC alloy membrane. In the PE/PMPC alloy membrane, the PMPC domains were located not only inside the membrane but also at the surface. Surface analysis of the PE/PMPC alloy membrane with X-ray photoelectron spectroscopy, wettability evaluation, and dynamic contact angle measurements revealed that the phospholipid polar groups in the PMPC covered the surface even after thermal treatment. Blood compatibility tests with attention to platelet adhesion and change in morphology of adhered platelets showed that the PE/PMPC alloy membrane had excellent platelet adhesion resistance. We finally concluded that the PE/PMPC alloy could be used as biomaterials instead of poly(vinyl chloride)-based materials. 相似文献
70.