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991.
Hiraku Hotta Harumoto Yamada Hironari Takaishi Tomoyuki Abe Hideo Morioka Toshiyuki Kikuchi Kyosuke Fujikawa Yoshiaki Toyama 《Journal of orthopaedic science》2005,10(6):595-607
Background The aim of this study was to observe time course changes in type II collagen synthesis in various regions of articular cartilage
affected with osteoarthritis (OA) by examining the expression of type II collagen C-propeptide (pCOL II-C) and mRNA in a rabbit
OA model.
Methods Osteoarthritis was experimentally induced by partial lateral meniscectomy in the knees of Japanese white rabbits. The cartilage
of the animals was then examined histologically over time. The degenerative area of articular cartilage was divided into three
areas, according to the degree of degeneration. The ability to synthesize type II collagen was estimated by the immunohistological
staining of pCOL II-C and the in situ hybridization of mRNA in type II collagen.
Results The positive rate of pCOL II-C immunostaining in chondrocytes was highest in the central-degenerative region 1 week after
surgery, and the highest rate in the para-degenerative region was observed 2 and 4 weeks after surgery. The percentage of
pCOL II-C positive cells increased as the histological degeneration score increased to moderate degeneration and then decreased
with further progression of the severity of cartilage degeneration. Examination by in situ hybridization revealed that the
regions marked by strong pCOL II-C mRNA expression were similar to those indicated by the immunohistology results.
Conclusions These results suggest that the type II collagen-synthesizing potential of chondrocytes is highest in moderately degenerated
areas of OA articular cartilage. Cartilage repair continues to be seen even as OA advances, although the reaction varies depending
on the stage of OA. 相似文献
992.
Patients with Parkinson's disease (PD) may show emotional impairment in the early stages of the disease. PD patients show disadvantageous decision-making, which is related to decreased emotional responses, as measured by skin conductance responses (SCRs). This pattern of decreasing SCRs is similar to that observed in amygdala-damaged patients. In facial expression recognition, PD patients did not show amygdala activation. In another study, PD patients did not show amygdala activations to unpleasant olfactory stimuli, which were observed in normal controls. Emotional impairment in PD patients may reflect amygdala dysfunction in early PD. 相似文献
993.
Cytoskeletal assembly induced by receptor-dependent or independent activation of bovine platelets was investigated. When platelets were preactivated with receptor-dependent stimulus, ADP or thrombin, cytoskeletal assembly was not induced repeatedly by the same agonist. However, in the case of receptor-independent stimulus, cryo-activation, the assembly was induced not only by receptor-dependent but also by independent stimulus. The desensitization, therefore, lies in the transmission of stimuli from receptors to cytoskeletal proteins. 相似文献
994.
995.
996.
The ether extract from the seeds of Swietenia mahagoni Jacq. (Meliaceae) was found to inhibit platelet-activating factor (PAF)-induced platelet aggregation. Systematic separation of the extract afforded twenty eight tetranortriterpenoids related to swietenine and swietenolide. Among them, several new compounds, named swietemahonin A, D, E, and G and 3-O-acetylswietenolide and 6-O-acetylswietenolide, showed a strong inhibition against PAF-induced aggregation in vitro and in vivo assays. 相似文献
997.
998.
Y Hitoshi S Mita A Tominaga Y Kikuchi E Sonoda K Takatsu Y Watanabe 《International immunology》1989,1(2):185-190
Interferon-gamma (IFN-gamma) is supposed to be produced by type 1 helper T cells (TH1) and inhibits IL-4-dependent B cell growth and differentiation. IL-5 (T cell-replacing factor, TRF), is a T cell-derived lymphokine which is predominantly produced by type 2 helper T cells (TH2) and regulates proliferation and differentiation of activated B cells. In this study, the effect of IFN-gamma on IL-5-dependent B cell growth and differentiation has been studied using murine chronic B cell leukemic cells (BCL1), normal splenic B cells, and cloned early B cell line. IFN-gamma selectively inhibits the IL-5-mediated proliferation of activated B cells as well as cloned early B cell lines at a low concentration (2 U/ml) in which polyclonal IgM production was not affected. This inhibitory effect of IFN-gamma occurs within 24 h after the onset of culture, as demonstrated by the inability of antibody to IFN-gamma to reverse totally the IFN-gamma-mediated suppressive effects if it was added later than 24 h after the onset of the culture. On the contrary, IL-5-mediated IgM secretion of BCL1 and IgA formation of LPS-stimulated normal B cells were relatively resistant to the suppressive effect of IFN-gamma. IFN-gamma does not affect the receptor expression for IL-5. Interestingly, IL-4-mediated IgG1 formation of LPS-stimulated B cells was markedly suppressed by IFN-gamma at 10 U/ml. These results strongly suggest that IFN-gamma may have differential effects on IL-5-mediated B cell triggering. 相似文献
999.
T Sato T Ozawa M Kikuchi M Nakano F Gejyo T Hanyu C Takahashi K Nakazono A Murasawa M Arakawa 《Ryūmachi》1990,30(1):53-59
A patient who developed mutilans-type arthropathy, splenomegaly, leukopenia, leg ulcer and massive hydroxyapatite accumulation during the course of progressive systemic sclerosis (PSS) was reported. A 56-years-old female had suffered Raynaud's phenomenon since the beginning of her third decade. She developed multiple symmetrical arthritis and morning stiffness at the age of 29, and was treated with NSAIDs and low dose corticosteroids under the diagnosis of rheumatoid arthritis (RA) Because of dysphagia and diarrhea, she was admitted in Niigata-Kenritsu Senami Hospital in September, 1987. Physical and roentgenographic examinations revealed diffuse scleroderma, mutilans-type arthropathy, lung fibrosis, splenomegaly and right leg ulcer. Laboratory examinations showed leukopenia, high titer of anti-DNA antibody, positive anti-Scl-70 antibody and mild hypocomplementemia. These findings suggested that she had PSS and Felty's syndrome. Furthermore, massive subcutaneous and intraarticular hydroxyapatite accumulation were noticed. The leg ulcer and laboratory data gradually improved with the combination therapy of corticosteroids, D-penicillamine and plasmapheresis. Although it has been well recognized that PSS patients reveal frequently the articular lesions similar to these of RA, severe mutilans-type arthropathy seen in this case is extremely rare. The joint contracture might be induced by hydroxyapatite accumulation, of which the early diagnosis seems to be very important in long-standing PSS patients. 相似文献
1000.
I Hara N Sato K Kikuchi S Kamidono 《Nihon Hinyōkika Gakkai zasshi. The japanese journal of urology》1991,82(1):24-32
The BCG 65 kDa protein is part of the 60 kDa heat-shock protein (hsp) family. It is clear that hsp has a huge homology among mammalian and bacterial cells. In our study, we have observed the relevance of this protein in the anti-tumor response. Antibody production against the BCG 65 kDa protein was determined by solid phase ELISA using the sera of 51 bladder cancer patients who have undergone BCG instillation therapy. The BCG 65 kDa protein was made by E. coli transfected with pTB12 (plasmid DNA) which encodes this protein. It was clearly observed that the level of serum antibody titer to this protein was raised by the above instillation therapy. In order to investigate the role of this protein in anti-tumor response, we developed monoclonal antibodies against BCG 65 kDa protein. Four monoclonal antibodies were developed (B-20, B-97, B-108, B-167). We also estimated the epitope defined by each monoclonal antibody by using the truncated protein which was produced by E. coli transfected with the deletion mutants of pTB12. At this stage, we proceeded with observation of the cross epitope between mammalian cancer cells and BCG after using these monoclonal antibodies. There is no cross epitope defined by B-20, B-97 and B-167 in mammalian cells. However, the epitope defined by B-108 exists in normal tissue as well as in bladder cancer cells. 相似文献