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81.
Kawano Y Fukuda J Itoh H Takai N Nasu K Miyakawa I 《American journal of reproductive immunology (New York, N.Y. : 1989)》2004,52(2):124-128
PROBLEM: In order to investigate the role of macrophage colony-stimulating factor (M-CSF) and monocyte chemoattractant protein -1 (MCP-1) in human ovulation, we studied the regulation of M-CSF and MCP-1 in cultured human granulosa cells. METHOD OF STUDY: Immortalized granulosa cells (GC1a) were cultured in serum-free medium, and incubated with interleukin (IL)-1alpha, IL-1 receptor antagonist (ra) and tumor necrosis factor (TNF)-alpha. The supernatants were collected, and M-CSF and MCP-1 were measured by ELISA. RESULTS: The levels of M-CSF and MCP-1 were increased after treatment with IL-1alpha (1 nm) and TNF-alpha (1 nm) in a time-dependent manner. The levels of M-CSF and MCP-1 were significantly increased after treatment with IL-1alpha and TNF-alpha in a dose-dependent manner. However, the levels of M-CSF and MCP-1 were significantly decreased by treatment with IL-1alpha (1 nm) and/or increasing concentrations of IL-1 ra. CONCLUSIONS: Our data indicated that M-CSF and MCP-1 were regulated by IL-1alpha and TNF-alpha. It was suggested that M-CSF and MCP-1 may play an important role in human preovulatory processes. 相似文献
82.
Marchildon PA Sugiyama T Fukuda Y Peacock JS Asaka M Shimoyama T Graham DY Fukada Y 《Journal of clinical microbiology》2003,41(4):1480-1485
It has been suggested that enzyme immunoassay (EIA) kits validated in one region may yield variable diagnostic performance results in different regions, possibly due to strain-specific differences in antibody responses in different populations. We tested (13)C-urea breath test-characterized serum samples from 109 U.S. patients and 288 Japanese patients using enzyme immunoassay with different preparations of high-molecular-weight cell-associated (HM-CAP) antigens that are conserved across Helicobacter pylori strains. Replicate antigens were prepared from five H. pylori clinical isolates. Eight antigen preparations were evaluated: two of U.S. origin and six of Japanese origin. The accuracies achieved with the eight antigen preparations ranged from 94.4 to 96.3% with the U.S. samples. With the Japanese samples the accuracies achieved ranged from 92.3 to 97.2%. Use of a pool of HM-CAP antigens prepared from isolates from Japan resulted in a higher median enzyme immunoassay value and slightly fewer samples with indeterminate results compared to the results obtained by use of the U.S. standard HM-CAP antigen for H. pylori-positive patients (accuracies, 97.2 and 92.3%, respectively), suggesting that variations in performance between both antigen source and patient population might be reduced by using antigens pooled from several strains. 相似文献
83.
Active matrix metalloproteinases in the tear fluid of individuals with vernal keratoconjunctivitis 总被引:3,自引:0,他引:3
Kumagai N Yamamoto K Fukuda K Nakamura Y Fujitsu Y Nuno Y Nishida T 《The Journal of allergy and clinical immunology》2002,110(3):489-491
Corneal epithelial lesions distinguish vernal keratoconjunctivitis (VKC) from other ocular allergic diseases. Such lesions result from degradation of the corneal epithelial basement membrane, which comprises mostly type IV collagen and laminin. Matrix metalloproteinase 2 (MMP-2) and MMP-9 catalyze the degradation of these 2 extracellular matrix proteins. The possible role of MMP-2 and MMP-9 in the pathogenesis of corneal lesions associated with VKC was investigated by assaying tear fluid for the presence of these enzymes. Tear fluid was collected from 6 eyes of 6 patients with active VKC, 14 eyes of 14 patients with active allergic conjunctivitis, and 6 eyes of 6 nonallergic healthy volunteers. Gelatin zymography revealed that the tear fluid of healthy volunteers contained inactive proforms of both MMP-2 and MMP-9 but not the active forms of these enzymes. Active forms of MMP-2 or MMP-9 were detected in a minority of patients with allergic conjunctivitis. However, with the exception of one individual for whom active MMP-9 was not detected, tear fluid from all patients with VKC contained both proforms and active forms of MMP-2 and MMP-9. These results implicate MMP-2 and MMP-9 in the pathogenesis of corneal epithelial disorders associated with VKC. 相似文献
84.
Jun Nakayama Kiyohiko Angata Edgar Ong Tsutomu Katsuyama Minoru Fukuda 《Pathology international》1998,48(9):665-677
Polysialic acid is a developmentally regulated carbohydrate composed of a linear homopolymer of a-2,a-linked sialic acid residues. This unique glycan is mainly attached to the neural cell adhesion molecule (N-CAM) and implicated in many morphogenic events of the neural cells by modulating the adhesive property of N-CAM. Recently, the cDNA that encodes polysialyltransferase, which is responsible for the polysialylation of N-CAM, was successfully cloned from three mammalian species. This review focuses on the molecular cloning of human polysialyltransferase, designated PST. it then describes the number of enzymes actually required for the polysialylation of N-CAM using an in vitro polysialyltransferase assay. Comparisons between PST and another polysialyltransferase, sialyltransferase X (STX), are made and it Is demonstrated that both enzymes can independently form polysiatic acid In vitro , but that during neural development they coordinately but distinctly synthesize polysialic acid on N-CAM. The role of polysialic acid in the central nervous system is also discussed. Finally, evidence that the two polysialyltransferases, PST and STX, apparently have distinct roles in the development of neural cells is provided by using a neurite outgrowth assay. 相似文献
85.
Possible contribution of follicular interleukin-1beta to nitric oxide generation in human pre-ovulatory follicles 总被引:2,自引:0,他引:2
Tao M; Kodama H; Kagabu S; Fukuda J; Murata M; Shimizu Y; Hirano H; Tanaka T 《Human reproduction (Oxford, England)》1997,12(10):2220-2225
The aim of this study was to investigate the relationships between
follicular nitric oxide (NO) metabolite concentrations and several related
variables, with special reference to follicular interleukin- 1beta
(IL-1beta). The follicular fluid from the leading and secondary follicles
was collected individually from 20 women undergoing in-vitro fertilization
(IVF) treatment, and the concentrations of nitrite (NO2-) and nitrate
(NO3-) were determined fluorometrically using 2,3- diaminonaphthalene. Both
follicular nitrite (r = 0.42, P < 0.01) and nitrate (r = 0.49, P <
0.001) were found to be significantly correlated with follicular IL-1beta
concentrations. There were also significant positive correlations between
follicular nitrate and the number of oocytes retrieved (P < 0.01) and
serum oestradiol concentration on the day of human chorionic gonadotrophin
(HCG) administration (P < 0.05). When follicular cells were incubated in
vitro with 10 ng/ml of IL-1beta for 24 h, nitrate generation was
significantly (P < 0.01) elevated compared with the control. In
conclusion, our study demonstrates that follicular IL-1beta and the number
of developing follicles are significant variables that affect follicular NO
concentrations, and points to the possible contribution of IL-1beta to NO
generation in human preovulatory follicles.
相似文献
86.
Cloning and nucleotide sequence of the gene encoding arginine deiminase of Mycoplasma arginini. 总被引:1,自引:1,他引:1 下载免费PDF全文
T Ohno O Ando K Sugimura M Taniai M Suzuki S Fukuda Y Nagase K Yamamoto I Azuma 《Infection and immunity》1990,58(11):3788-3795
The existence of a mycoplasmal arginine deiminase which catalyzes the conversion of L-arginine to L-citrulline has been postulated. Here we show the partial amino acid sequence of arginine deiminase of Mycoplasma arginini and the complete nucleotide sequence of the arginine deiminase gene of M. arginini. The open reading frame deduced from this sequence consists of 1,230 bp encoding 410 amino acids. The mature form of this enzyme contains 409 amino acids after the deletion of the first methionine. In this open reading frame, TGA nonsense codons are used as tryptophan codons; this usage was verified by determination of the amino acid sequence. The molecular weight of the enzyme calculated from the deduced amino acid sequence is 46,372. Recently, the nucleotide sequence of the arginine deiminase gene of M. arginini was reported by Kondo et al. (K. Kondo, H. Sone, H. Yoshida, T. Toida, K. Kanatani, Y.-M. Hong N. Nishino, and J. Tanaka, Mol. Gen. Genet. 221:81-86, 1990). However, their sequence differed from ours in several places and especially at the C terminus. 相似文献
87.
Pathogenesis of Rinderpest Virus Infection in Rabbits I. Clinical Signs, Immune Response, Histological Changes, and Virus Growth Patterns 下载免费PDF全文
Kazuya Yamanouchi Fumitoshi Chino Fumio Kobune Akiko Fukuda Yasuhiro Yoshikawa 《Infection and immunity》1974,9(2):199-205
Rabbits were intravenously inoculated with an attenuated rinderpest virus (L strain), and general patterns of the disease were investigated. The rabbits developed fever with concomitant occurrence of diarrhea and lymphopenia. Early production of interferon was followed by a rise of neutralizing antibody. Histological examinations revealed an involvement of all of the lymphoid tissues, with primary lesions consisting of necrosis of the lymphoid follicles and formation of giant cells. Immunofluorescent examinations suggested that the virus growth was present in almost all of the lymphoid tissues. The possibility of application of this experimental system for the study of systemic infection by measles virus was discussed. 相似文献
88.
Kai K Nasu K Nakamura S Fukuda J Nishida M Miyakawa I 《Molecular human reproduction》2002,8(2):176-180
Human endometrial stromal cells (ESC) can produce a variety of chemokines, especially after inflammatory stimulation. Interferon-gamma-inducible protein-10 (IP-10) is a potent chemoattractant for lymphocytes, and belongs to the family of non-ELR CXC chemokines. The expression of IP-10 in ESC after stimulation with interferon-gamma (IFN-gamma), interleukin-1 beta (IL-1 beta), tumour necrosis factor-alpha (TNF-alpha), or lipopolysaccharide (LPS) was evaluated using an enzyme-linked immunosorbent assay and Northern blot analysis. A small amount of IP-10 protein was detected in the culture media of unstimulated ESC. The expression of IP-10 mRNA was detected in ESC. IFN-gamma, IL-1 beta, TNF-alpha and LPS significantly stimulated the expression of IP-10 mRNA and protein in ESC. These results suggest that the production of IP-10 by ESC is regulated by inflammatory mediators. The modulation of IP-10 concentrations in the local environment may contribute to the normal and pathological processes of human reproduction by regulating leukocyte trafficking in the endometrium. 相似文献
89.
Interferon-alpha and dexamethasone inhibit adhesion of T cells to endothelial cells and synovial cells 下载免费PDF全文
K. Eguchi A. Kawakami M. Nakashima H. Ida S. Sakito N. Matsuoka K. Terada M. Sakai Y. Kawabe T. Fukuda T. Ishimaru K. Kurouji N. Fujita T. Aoyagi K. Maeda S. Nagataki 《Clinical and experimental immunology》1992,88(3):448-454
We investigated whether interferon-gamma (IFN-gamma), interferon-alpha (IFN-alpha) and glucocorticoids affected the adhesion of T cells to human umbilical endothelial cells or human synovial cells. About 30% of peripheral blood T cells could bind to unstimulated endothelial cells, but only a few T cells could bind to unstimulated synovial cells. When both endothelial cells and synovial cells were cultured with recombinant IFN-gamma (rIFN-gamma), the percentage of T cell binding to both types of cells increased in a dose-dependent manner. rIFN-alpha and dexamethasone blocked the T cell binding to unstimulated endothelial cells. Furthermore, rIFN-alpha and dexamethasone suppressed T cell binding to both endothelial cells and synovial cells stimulated by IFN-gamma, and also inhibited intercellular adhesion molecule-1 (ICAM-1) expression on both endothelial cells and synovial cells stimulated by IFN-gamma. These results suggest that IFN-alpha and glucocorticoids may inhibit T cell binding to endothelial cells or synovial cells by modulating adhesion molecule expression on these cells. 相似文献
90.
Beta-catenin mutations are frequent in calcifying odontogenic cysts, but rare in ameloblastomas 总被引:2,自引:0,他引:2 下载免费PDF全文
Sekine S Sato S Takata T Fukuda Y Ishida T Kishino M Shibata T Kanai Y Hirohashi S 《The American journal of pathology》2003,163(5):1707-1712
We have reported previously that alterations to beta-catenin occur frequently in adamantinomatous craniopharyngioma. Based on its histological resemblance to some odontogenic tumors, we suspected the presence of common genetic alterations among these tumors. To address this issue, 11 cases of calcifying odontogenic cyst (COC) and 20 cases of ameloblastoma were investigated for the presence of beta-catenin mutations and beta-catenin expression. Ten COCs were successfully analyzed by direct sequencing, and nine of them were found to harbor somatic beta-catenin mutations. Immunohistochemically, all of the COCs showed nuclear and cytoplasmic expression of beta-catenin with a heterogeneous pattern. No beta-catenin mutations were found in ameloblastomas, except for one case of the follicular type. All follicular ameloblastomas exhibited moderate nuclear and cytoplasmic accumulation of beta-catenin, in contrast to the predominantly membranous expression seen in the plexiform type. beta-Catenin mutation is considered to be a characteristic genetic feature of COC, and may play a critical role in its histogenesis. Although ameloblastoma closely resembles COC histologically, the two have genetically distinctive features. 相似文献