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81.
82.
Nakajima-Takenaka C Sakata S Kato S Ohga Y Murata KY Taniguchi S Takaki M 《Experimental physiology》2005,90(4):635-644
We have previously reported that continuous infusion of dobutamine into the coronary artery induces positive inotropic effects but induces no detrimental effects in cross-circulated, excised normal rat hearts and even in Ca2+ overload-induced contractile failing rat hearts. However, we hypothesized that some detrimental effects on left ventricular (LV) function are induced after continuous dobutamine infusion and the following clearance of blood dobutamine, as is the case after beta-adrenergic receptor stimulation. To test this hypothesis, we investigated LV mechanical work and energetics in the same type of preparations that underwent continuous dobutamine infusion and clearance of blood dobutamine. We found that both mean end-systolic pressure and systolic pressure-volume area (PVA; a measure of total mechanical energy per beat) at midrange LV volume were significantly (P < 0.01) decreased. The mean myocardial oxygen consumption per beat intercept, which is composed of for the total Ca2+ handling in excitation-contraction coupling and basal metabolism, of the and PVA linear relation was also significantly (P < 0.05) decreased (n=8). The mean slope of the linear relation was unchanged in such hearts. Post-dobutamine basal metabolism was unchanged (n = 5 of the 8 hearts). The moderate proteolysis of a cytoskeleton protein, alpha-fodrin was identified (n = 7 of the 8 hearts with the decreased intercept), after clearance of blood dobutamine. In agreement with our hypothesis, the detrimental effect of the post-beta-adrenergic receptor stimulation was induced by a moderate concentration of dobutamine; we found systolic dysfunction due to the impairment of Ca2+ handling in excitation-contraction coupling in the rat LV and proteolysis of a cytoskeleton protein, alpha-fodrin. 相似文献
83.
84.
Tokuhiro Ishihara Yoshimi Yamashita Yoshiko Okuzono Tadaaki Yokota Mutsuo Takahashi Toshiaki Kamei Fumiya Uchino Noboru Matsumoto Shiro Miwa Hisaichi Fuji Takeshi Kozaki 《Ultrastructural pathology》1985,8(1):13-23
By light and electron microscopy, we observed foamy cells in the spleens from a patient with hemolytic anemia due to red cell adenosine deaminase (ADA) overproduction, a patient with rheumatoid arthritis (RA) treated with gold, and patients with idiopathic thrombocytopenic purpura (ITP)
The foamy cells associated with red cell ADA overproduction were essentially similar to Gaucher-like cells described in patients with thalassemia, and it was suggested that the accelerated destruction of red cells was one of the factors responsible for the development of foamy cells. Foamy cells in ITP and RA were closely associated with an increased destruction of platelets in the spleen. Morphologic transitions between phagocytosed platelets and myelinlike materials were traced in these disorders. In RA, however, foamy cells were heterogeneous from an ultrastructural standpoint, with different cytoplasmic inclusions. In addition to myelinlike materials, dense bodies, vacuoles with flocculent materials, and gold were noted in most of foamy cells. As gold compounds are known to inhibit lysosomal enzymes, we surmise that an acquired disturbance in lysosomal digestion is partially responsible for the accumulation of intermediate metabolites.
In the pathogenesis of foamy cells associated with blood cell dyscrasia, the accelerated destruction of blood cells and/or acquired disorders in catabolic pathways within the macrophages are suggested to be the underlying mechanism of an intralysosomal accumulation of incompletely degraded cellular debris. 相似文献
The foamy cells associated with red cell ADA overproduction were essentially similar to Gaucher-like cells described in patients with thalassemia, and it was suggested that the accelerated destruction of red cells was one of the factors responsible for the development of foamy cells. Foamy cells in ITP and RA were closely associated with an increased destruction of platelets in the spleen. Morphologic transitions between phagocytosed platelets and myelinlike materials were traced in these disorders. In RA, however, foamy cells were heterogeneous from an ultrastructural standpoint, with different cytoplasmic inclusions. In addition to myelinlike materials, dense bodies, vacuoles with flocculent materials, and gold were noted in most of foamy cells. As gold compounds are known to inhibit lysosomal enzymes, we surmise that an acquired disturbance in lysosomal digestion is partially responsible for the accumulation of intermediate metabolites.
In the pathogenesis of foamy cells associated with blood cell dyscrasia, the accelerated destruction of blood cells and/or acquired disorders in catabolic pathways within the macrophages are suggested to be the underlying mechanism of an intralysosomal accumulation of incompletely degraded cellular debris. 相似文献
85.
Tadaaki Yokota Yoshimi Yamashita Yoshiko Okuzono Mutsuo Takahashi Shigeyoshi Fujihara Shin'ichiro Akizuki Tokuhiro Ishihara Fumiya Uchino Takako Iwata 《Pathology international》1984,34(3):663-668
A case of malignant cystosarcoma phyllodes of the prostate is reported in a 45-year-old male. This tumor was composed of benign columnar or squamous cystic folds and sarcomatous stroma including rhabdomyomatous elements. The prostatic origin of the tumor was clearly proved by the unlabeled immunoperoxidase method. ACTA PATHOL. JPN. 34: 663–668, 1984. 相似文献
86.
Mikio Koide Masayuki Kato Eishun Tsuchida Yoshimi Kurimura 《Macromolecular chemistry and physics.》1981,182(2):283-291
Polymeric cobalt dinitrogen complexes were synthesized by two different methods: by the ligand substitution reaction of polymers 5a – c and 6a – c , containing 4-diphenylphosphinophenylethylene units ( 3 ) or 4-diphenylphosphinomethylphenylethylene units ( 4 ), respectively, with hydridodinitrogentris(triphenylphosphine)cobalt(I) (CoH(N2)(PPh3)3), or by the direct reaction of tris(acetylacetonato)cobalt(III) with triphenylphosphine, the polymers 5a – c or 6a – c , and triisobutylaluminium under nitrogen. The intensity of the v band in the IR spectrum of the polymeric dinitrogen complex was found to be about four times as that of CoH(N2)(PPh3)3. Ammonia was formed after hydrolysis of the complex, which was prepared by mixing a tetrahydrofuran solution of naphthaline, lithium, and titanium tetrachloride with the polymeric dinitrogen complex. The yields of ammonia in the case of the polymeric complexes were high in comparison with that obtained with CoH(N2)(PPh3)3. The highest yields of ammonia were obtained when a mole ratio [P?]/[Co] < 1 ([P?] is the concentration of phosphino groups in the polymer and [Co] is that of Co in CoH(N2)(PPh3)3), a temperature of ?20°C, and a reaction time of 1 h were applied. 相似文献
87.
Simultaneous occurrence of medullary and follicular carcinoma in the same thyroid lobe 总被引:2,自引:0,他引:2
T Tanaka N Yoshimi N Kanai H Mori K Nagai A Fujii S Sakata N Tokimitsu 《Human pathology》1989,20(1):83-86
A rare case of the simultaneous development of medullary and follicular carcinoma of the thyroid gland in a 51-year-old Japanese woman is examined. A preoperative diagnosis was made by needle aspiration cytology. Neoplastic cells of the medullary carcinoma were positive for calcitonin and carcinoembryonic antigen, whereas the tumor cells of the follicular carcinoma were negative for these substances. This case presents evidence that, in rare cases, two malignant epithelial neoplasms of different origins can occur in the same lobe of the thyroid. 相似文献
88.
K. Taniguchi H. Tsuchie S. Kageyama M. Iwasaki T. Takagi F. Sasao S. Ueda T. Kurimura 《Archives of virology》1998,143(5):881-890
Summary. HIV-1 p17 antigen has been studied for its biological significance in vitro as well as its immunological roles in vivo. By
immunological approach of antibody-binding to HIV-1 p17 antigens of several subtypes in combination with computerized analysis
of those tertial structures, it became evident that, irrelevant of similarity of linear amino acid sequence of different HIV-1
subtypes, a few amino acid substitutions close to or distant from specified epitope(s) affected their tertial structure resulting
in change in ability of its binding to selected antibody. ELISA employing two monoclonal antibodies, A144 and C415, could
detect p17 of subtypes A and B, but not of subtypes C, D, and E. Since the epitope site corresponding to A144 has been reported
to be important for biological activity of p17 of HIV-1, change in tertial structure around this epitope may explain some
difference in biology of HIV-1, such as infectivity of subtypes B and E.
Accepted January 9, 1998 Received October 24, 1997 相似文献
89.
Detection of capsid antigen of human papillomavirus (HPV) in benign lesions of female genital tract using anti-HPV monoclonal antibody. 总被引:3,自引:0,他引:3
T Iwasaki T Sata M Sugase Y Sato T Kurata K Suzuki H Ohmoto S Iwamoto T Matsukura 《The Journal of pathology》1992,168(3):293-300
We established a murine monoclonal antibody (K1H8) to human papillomavirus (HPV) using alkaline-disrupted virions of HPV type 1 (HPV-1) as the immunogen. K1H8 recognized a 57 kD capsid protein of HPV-1 and detected the antigen in paraffin sections of formalin-fixed tissue. With K1H8, we examined immunohistochemically 68 biopsy specimens obtained from the female genital tract. The specimens were histologically condyloma acuminatum or koilocytotic lesions with or without dysplasia and each specimen was found to harbour a single type of genital HPV, such as types 6, 11, 16, 18, 31, 33, 42, 51, 52, 56, and 58, by Southern blot hybridization analysis. The antigen was localized in the nuclei and occasionally in the cytoplasm of squamous cells showing koilocytotic changes. Eighty-four per cent of the specimens (57 cases) showed positivity for the antigen, indicating that K1H8 is a broadly-reactive antibody to various genital HPVs. The results suggest that benign mucosal lesions of the female genital tract are more frequently associated with viral production and are a potential source of transmission. 相似文献
90.
Fukuhara A Irie K Yamada A Katata T Honda T Shimizu K Nakanishi H Takai Y 《Genes to cells : devoted to molecular & cellular mechanisms》2002,7(10):1059-1072
BACKGROUND: In polarized epithelial cells, cell-cell adhesion forms specialized membrane structures comprised of claudin-based tight junctions (TJs) and of E-cadherin-based adherens junctions (AJs). These structures are aligned from the apical to the basal side of the lateral membrane, but the mechanism of this organization remains unknown. Nectin is a Ca2+ independent immunoglobulin-like cell-cell adhesion molecule which localizes at AJs. Nectin is associated with E-cadherin through their respective cytoplasmic tail-binding proteins, afadin and catenins, and involved in the formation of AJs in cooperation with E-cadherin. We show here that nectin is also involved in the formation of TJs. RESULTS: During the formation of the junctional complex consisting of AJs and TJs in Madin-Darby canine kidney (MDCK) cells, claudin and occludin accumulated at the apical sites of the nectin-based cell-cell adhesion sites. This accumulation of claudin and occludin was inhibited by inhibitors acting on the trans interaction of nectin. The barrier function of TJs was also impaired by the nectin inhibitors. It has been shown that a phorbol ester promotes the formation of a TJ-like structure in an E-cadherin-independent manner. This phorbol ester-induced formation of the TJ-like structure was also inhibited by the nectin inhibitors. CONCLUSIONS: These results suggest a role of the nectin-afadin system in the organization of TJs as well as AJs in epithelial cells. 相似文献