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排序方式: 共有7378条查询结果,搜索用时 15 毫秒
71.
B cell development is perturbed in bone marrow from c-fos/v-jun doubly transgenic mice 总被引:2,自引:0,他引:2
Fujita Kenji; Miki Nobuhiko; Mojica Mariluz P.; Takao Shintaro; Phuchareon Janyaporn; Nishikawa Shin-Ichi; Sudo Tetsuo; Tokuhisa Takeshi 《International immunology》1993,5(2):227-230
c-fos and c-jun gene products form a heterodimeric complex (AP-1)that regulates target gene expression by binding to a specificDNA sequence motif. In order to study a role of AP-1 (Fos/Jun)in growth and differentiation of immature B lineage cells, wehave established and mated two independent transgenic mice carryingthe mouse c-fos gene or the viral v-Jun gene fused to the H-2Kpromoter. IL-7 dependent bone marrow cell culture from doublytransgenic (H2-fos/jun) mice demonstrated severe delay of earlyB cell development. Proliferation of pre-B cells in the freshbone marrow from HZ-fos/jun mice to IL-7 stimulation was verylow. These results suggest that the deregulated production ofAP-1 perturbs IL-7 mediated proliferation and differentiationof immature B cells. 相似文献
72.
Ping Ii Hiroshi Kawachi Tetsuo Morioka Mlchiaki Orikasa Takashi Oite Zhen Sheng Shi Fujio Shimizu 《Pathology international》1997,47(7):430-435
The effects of treditional Chinese medlclne (Salrel-to) on experimental glomerulonephritls Induced In rats by monodonal antibody (mAb) 1–22–3 lnjectlon was examined. The level of proteinuria in the Sairel-to-treated group was significantly lower than that In the PBS treated group. This suppressive effect was caused by the major component of Sealer-to, Syo-salko-to but not by another component, Gorel-san. The suppressive effect of Syo-salko-to was Identified In Its components ( Bupleuri radix, Pindilae tuber and Zingibers rhizoma ), but not In the other combined components ( Ginseng radix and Zizyphl fructus ). Further study weeled that the suppressive effects of the combined components were mainly derived from Bupleuri radix . It was demonstrated that the actual active Ingredient is probably Salkosaponin-d. Light microscopy revealed that Sairel-to and Its effective components suppressed the proliferation of mesanglal cells and mesanglal matrix expansion. Semi quantitative morphological studies of glomerular lesions on the eighth day showed that Syo-salko-to and Its combined components ( Bupleuri radix, Zinglberis rhizoma and Pinelliae tuber ) suppressed mesanglal matrix expansion significantly compared with phosphate-buffered saline control groups (matrix score: 28.0±19.1 vs 102.3±14.1; 30.9±30.1 vs 102.3±14.1, p<0.005, respectively). It was concluded that Salkosaponln-d, as well as Bupleuri radix , Syo-salko-to and Sairel-to can suppress proteinurla and morphological changes In the rat glomerulonephritls model Induced by mAb 1–22–3. 相似文献
73.
74.
S. Oh-ishi Takako Kizaki Tomomi Ookawara Koji Toshinai Shukoh Haga Fujio Karasawa Tetsuo Satoh Naokazu Nagata L. L. Ji Hideki Ohno 《Pflügers Archiv : European journal of physiology》1998,435(6):767-774
The aim of the current study was to elucidate the synergism of dietary calcium restriction and exhaustive exercise in the
antioxidant enzyme system of rat soleus muscle, and to investigate the involvement of neutrophils in exercise-induced muscle
damage. Forty-eight male Wistar rats were assigned to the following groups: control (C) or calcium-restricted [1 month (1 M)
or 3 months (3 M)]. Each group was subdivided into acutely exercised or non-exercised groups. Soleus muscle from each rat
was analysed to determine the levels of antioxidant enzymes [Mn-superoxide dismutase (SOD), Cu,Zn-SOD, glutathione peroxidase
(GPX), and catalase (CAT)]. Dietary calcium restriction resulted in calcium deficiency and upregulated the antioxidant enzymes
examined except GPX. Conversely, exhaustive exercise significantly decreased GPX and CAT, but not SODs activities in the calcium-restricted
(1 M and/or 3 M) rats. Contents of immunoreactive Mn-SOD and Cu,Zn-SOD were only increased in the 3 M rats. During calcium
restriction, the mRNA expression of both forms of SOD showed initial upregulation, followed by downregulation. Exhaustive
exercise significantly increased the mRNA expressions only in the 3 M rats. Moreover, exhaustive exercise markedly increased
myeloperoxidase activity in soleus muscles from the 1 M and 3 M rats compared with the C rats, and significantly enhanced
the ability of neutrophils to generate superoxide in the 3 M rats. The results demonstrate that dietary calcium restriction
upregulates certain antioxidant enzyme activities in rat soleus muscle, indicating an enhanced resistance to potential increases
in intracellular reactive oxygen species. The results also suggest that exhaustive exercise may cause oxidative damage in
soleus muscle of calcium-deficient rats through the activation of neutrophils.
Received: 4 August 1997 / Received after revision: 29 September 1997 / Accepted: 26 November 1997 相似文献
75.
Kazunaga Agematsu Tetsuji Kobata Feng-Chun Yang Takayuki Nakazawa Keitaro Fukushima Masashi Kitahara Tetsuo Mori Kanji Sugita Chikao Morimoto Atsushi Komiyama 《European journal of immunology》1995,25(10):2825-2829
CD27 is a T cell activation antigen expressed on a majority of peripheral blood T cells. CD27 is also expressed on a subpopulation of human B cells, and it is reported that CD27+ B cells secrete both IgG and IgM. CD70, a ligand for CD27, is expressed on activated T and B cells, suggesting an interaction between T and B cells via CD27/CD70 ligation. Here, we analyze B cell immunoglobulin synthesis using a CD70 transfectant and present functional data showing that B cells secrete large amounts of IgG and IgM as a result of the CD27/CD70 interaction. A flow cytometric analysis showed that CD27 expression was increased and CD70 was expressed on tonsillar and peripheral blood B cells after activation with Staphylococcus aureus Cowan strain (SAC) plus interleukin (IL-2). In addition, the proliferation of B cells was enhanced mildly by the addition of CD70 transfectant, and its proliferation was blocked by anti-CD70 mAb. More importantly, the CD70 transfectant enhanced IgG and IgM production by purified B cells greatly in the presence of SAC plus IL-2. The enhancement was completely blocked by the addition of either anti-CD70 mAb or anti-CD27 mAb. Strongly suggesting that the interaction of CD27 with its ligand, CD70, on B cells plays an important role in B cell growth and differentiation to produce IgG and IgM. 相似文献
76.
Shuichi Seki Hiroki Sakaguchi Nobuyoshi Kawakita Atsushi Yanai Tetsuo Kuroki Kenzo Kobayashi 《Virchows Archiv : an international journal of pathology》1993,422(2):133-143
The proliferative activity and ultrastructural characteristics of proliferating biliary epithelial cells were analysed immunohistocytochemically in 39 biopsied liver specimens from patients with acute viral hepatitis, chronic hepatitis and liver cirrhosis using a monoclonal antibody against DNA polymerase (DNA-PA). In acute viral hepatitis with perivenular confluent necrosis, proliferation of typical bile ducts was found frequently in portal areas. In chronic aggressive hepatitis and cirrhosis, ductular proliferation of both typical and atypical forms was found in enlarged portal and periportal areas and in confluent necrotic areas. The number of proliferating biliary epithelial cells that stained positive for DNA-PA was small. There were very few positively stained cells in atypical bile ducts in confluent necrotic areas of cirrhosis. Atypical bile ducts seen in chronic aggressive hepatitis, cirrhosis and acute hepatitis with confluent necrosis were positively stained for both cytokeratins 8 and 19. In cirrhosis, the number of stained biliary epithelial cells in typical bile ducts was larger than the number of such cells in atypical bile ducts (P< 0.01). By electron microscopy, the cells positively stained for DNA-PA were mostly so-called clear cells with irregular nuclei containing coarse nucleoplasm, and a few small cells with scanty cytoplasm and few organelles. 相似文献
77.
78.
Association of gastric epithelial apoptosis with the ability of Helicobacter pylori to induce a neutrophil oxidative burst 总被引:3,自引:0,他引:3
Mizuki I Shimoyama T Fukuda S Liu Q Nakaji S Munakata A 《Journal of medical microbiology》2000,49(6):521-524
Both polymorphonuclear cell infiltration and increased epithelial apoptosis are seen in gastric mucosa in the presence of Helicobacter pylori infection. This study examined the association between bacterial ability to stimulate an oxidative burst in neutrophils and epithelial apoptosis. Biopsy specimens were obtained from 15 patients to detect apoptotic cells by the TUNEL method. H. pylori strains isolated from corresponding stomach biopsy samples were tested for the ability to stimulate an oxidative burst in human neutrophils. Neutrophils were isolated from healthy subjects without H. pylori infection and the oxidative burst was measured by flow cytometry with dichlorofluorescein diacetate. Stimulation with H. pylori increased both the percentage of activated cells and fluorescence intensity. There was a significant positive correlation between the number of epithelial apoptotic cells and fluorescence intensity. Increased neutrophil oxidative burst stimulated by H. pylori may play a role in enhanced gastric mucosal DNA damage and consequent atrophic gastritis and gastric cancer. 相似文献
79.
Kengo Funakoshi Masato NakanoYoshitoshi Atobe Tetsuo KadotaRichard C. Goris 《Neuroscience letters》2006
The visceral reflexes of the pelvic organs are mediated by connections between primary afferents innervating the pelvic organs and parasympathetic preganglionic neurons in the intermediolateral column of the sacral spinal cord. The present immunohistochemical study revealed many varicosities expressing transient receptor potential vanilloid 1 (TRPV1) that were closely apposed to the preganglionic neuronal perikarya at embryonic day 16 in mice. Many, but not all, varicosities expressing TRPV1 in the intermediolateral column were also immunopositive for calcitonin gene-related peptide. In contrast, no nerve fibers expressing TRPV1 projected to the sympathetic preganglionic cell column in the lumbar spinal cord in prenatal stages. The results of the present study raised the possibility that the primary afferents transmit signals elicited by the activation of TRPV1 receptors to the sacral parasympathetic preganglionic neurons. Thus, the functional circuit for pelvic spinal reflexes, such as micturition induced by urine influx, might develop in the prenatal stages in mice. 相似文献
80.
Tetsuo Itoh 《Pathology international》1968,18(2):207-225
In allogeneic immunity against tumors induced by methylcholanthrene in the W/KA strain rat, serum antibody agglutinated red blood cells of the W/KA strain rat. The allogeneic antiserum was cytotoxic to the lymphocyte, but not to the tumor cells induced by methylcholanthrene.
In vitro and in vivo studies of allogeneic immunization of tumor suggested that immune macrophages or histiocytes play a major role in the rejection of transplanted tumor. Direct adhesion of immune macrophages with target cells is necessary for destruction of allografted tumor.
In antitransplantation immunity of the syngeneic and autochthonous rat, there was no cytotoxic serum antibody demonstrable in so far as routine techniques were employed. However, this may not exclude the existence of specific serum antibody or non-cytotoxic reaction with target cells of specific serum antibody. On the other hand, immune macrophages were always cytotoxic to target tumor cells, thus showing tumor specifity.
Experiment in which diffusion chambers were inserted into syngeneic immune rats suggested the possible participation of a humoral factor which was released from the immune rats immediately after contact with target cells and transform normal macrophages to immunologically active macrophages. The ascites macrophages have the greatest effective cytotoxic action among the three types of cells. In allogeneic tumor immunity, one immune macrophage can damage one target tumor cell showing single hit interaction. ACTA PATH. JAP. 18: 207–225, 1968. 相似文献
In vitro and in vivo studies of allogeneic immunization of tumor suggested that immune macrophages or histiocytes play a major role in the rejection of transplanted tumor. Direct adhesion of immune macrophages with target cells is necessary for destruction of allografted tumor.
In antitransplantation immunity of the syngeneic and autochthonous rat, there was no cytotoxic serum antibody demonstrable in so far as routine techniques were employed. However, this may not exclude the existence of specific serum antibody or non-cytotoxic reaction with target cells of specific serum antibody. On the other hand, immune macrophages were always cytotoxic to target tumor cells, thus showing tumor specifity.
Experiment in which diffusion chambers were inserted into syngeneic immune rats suggested the possible participation of a humoral factor which was released from the immune rats immediately after contact with target cells and transform normal macrophages to immunologically active macrophages. The ascites macrophages have the greatest effective cytotoxic action among the three types of cells. In allogeneic tumor immunity, one immune macrophage can damage one target tumor cell showing single hit interaction. ACTA PATH. JAP. 18: 207–225, 1968. 相似文献