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21.
Livers from fed rats (180-240 g) were perfused noncyclically with a hemoglobin-free medium in vitro to determine whether vasoactive intestinal peptide (VIP) increases hepatic glucose production through a cAMP- or a Ca(2+)-dependent mechanism. Glucose output did not increase, but cAMP increased maximally during 10(-9) M VIP infusion. When VIP was perfused at 10(-8) M or more, glucose output increased dose dependently, whereas cAMP increased only a little during the VIP infusion, but increased greatly after the infusion. When Ca2+ was excluded from the perfusate, glucose output produced by 10(-8)-10(-7) M VIP was only 40% of that observed in the Ca(2+)-containing perfusion, and the increase in cAMP was abolished almost completely. By adding 10(-7) M A23187 for 10 min during the infusion of 10(-9) M VIP, cAMP, which increased with VIP alone, decreased during the A23187 infusion and increased again after the cessation of the A23187 infusion, whereas glucose output increased during the A23187 infusion. These results were similar to those observed with higher concentrations of VIP. When 10(-4) M isobutylmethylxanthine and 10(-8) M VIP were infused concurrently, cAMP increased rapidly during the infusion and decreased after the infusion. In conclusion, 1) glycogenolysis is produced by VIP through a Ca(2+)-dependent mechanism, rather than a cAMP-dependent one; and 2) the restriction of cAMP accumulation during the infusion of high concentrations of VIP is caused by Ca(2+)-induced phosphodiesterase activation. 相似文献
22.
Yusuke Ando Takahiro Nishida Shigeki Morita Munetaka Masuda Yukihiro Tomita Ryuji Tominaga 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2006,54(8):335-337
Infective endocarditis of the mitral area accompanied by anorexia nervosa is extremely rare. A 34-year-old Japanese woman presented with high fever and a heart murmur that had developed over the previous 2-month period. Echocardiography revealed mitral regurgitation and vegetation attached to the anterior mitral leaflet, which had markedly prolapsed to the left atrium. We removed the vegetation with a small part of the anterior mitral leaflet and successfully repaired the mitral valve. The patient showed good recovery, and the mitral regurgitation and left ventricular chamber size had satisfactorily decreased at 2 months after the operation. 相似文献
23.
We investigated the expression of adhesion molecules of lymphocyte function-associated antigen-1 alpha (LFA-1 alpha) and its ligand intercellular adhesion molecule-1 (ICAM-1) on 74 well-characterized B cell lymphomas. The LFA-1 was expressed on B cell lymphomas (21/74; 28 per cent), but to a lesser degree than ICAM-1 which was highly expressed (48/74 cases; 64 per cent). From the results of bone marrow examination of 39 cases with B cell lymphomas, 13 of 16 cases with a lack of ICAM-1 molecule showed a higher incidence of marrow involvement, but nine of 23 cases with the expression of ICAM-1 molecule showed a lower incidence. These findings suggest that the lack of expression of the ICAM-1 molecule by B cell lymphomas correlates with bone marrow involvement by lymphoma cells (p < 0.05). Expression of the LFA-1 molecule appears not to correlate with marrow involvement (p < 0.05). 相似文献
24.
Monoclonal antibodies directed against human, alpha-atrial natriuretic polypeptide (alpha-ANP; Human, 1-28) were obtained by somatic cell fusion between P3-X63-Ag8.653 myeloma cells and spleen cells from a BALB/c mouse immunized with human, alpha-ANP selectively coupled to keyhole limpet hemocyanin. From the analysis of polyclonal sera with respect to determinant specificity before the fusion, the strategy was primarily used to pick up monoclonal antibody specific for the N-terminal residues of human, alpha-ANP. Screening of antibodies in the hybridoma culture supernatants were performed by binding to iodinated synthetic human, alpha-ANP. Two stable clones producing anti-human, alpha-ANP antibodies, designated 13A1 and 10B1, were obtained by the limiting dilution technique. The ability of ANP(Rat, 1-28) to inhibit binding of 125I-human, alpha-ANP to these antibodies was almost equipotent to ANP(human, 1-28). However, ANP fragments (Human, 7-28) and (18-28) did not compete the binding completely. These results suggest that both 13A1 and 10B1 monoclonal antibodies can specifically recognized N-terminus of human, alpha-ANP, and may be a useful tool to investigate receptor binding of human, alpha-ANP by the antagonizing effect. 相似文献
25.
Yonson Ku Masahiro Tominaga Takeshi Iwasaki Tetsushi Kitagawa Ichiro Maeda Masafumi Shiotani Shinya Kusunoki Yoko Maekawa Masahiro Samizo Takumi Fukumoto Yoshikazu Kuroda Shozo Hirota Yoichi Saitoh 《Surgery today》1996,26(5):305-313
The results of treating 12 consecutive patients with unresectable colorectal hepatic metastases with a hepatic arterial infusion of high-dose Adriamycin, 100–120 mg/m2, using hepatic venous isolation (HVI) and charcoal hemoperfusion (CHP) are reported herein. Adriamycin was administered over 5–15 min under extracorporeal drug elimination by HVI-CHP. HVI was percutaneously accomplished by either the double-balloon technique using a Fogarty occlusion catheter (8/22F) or a balloon-tipped catheter (16F). During the infusion, isolated hepatic venous blood was filtered by CHP and pumped into the left axillary vein. There were no lethal complications, and good hemodynamic tolerance to HVI-CHP was confirmed. Tumor liquefaction accompanied by a sharp decrease in serum carcinoembryonic antigen levels by more than 50% of pretreatment levels was observed in 6 of the 12 patients 1 month after treatment. Apart from chemical hepatitis, which developed in 11 (92%) of the patients, the Adriamycin toxicities were well controlled following the development of nausea and vomiting in 2 patients (17%), leukopenia <2,000/mm3 in 3 (25%), and gastric ulcer in 1 (8%). These results indicate that this method is a safe and useful procedure for otherwise hazardous high-dose intraarterial chemotherapy in patients with unresectable hepatic tumors. 相似文献
26.
Tsukasa Tsunoda Toshifumi Eto Takahito Tsurifune Shigeki Tokunaga Tatsuhiro Ishii Koichi Motojima Teiji Matsumoto Tohru Segawa Kazuhide Ura Hiroshi Fukui 《Pathology international》1991,41(10):763-770
A solid and cystic tumor (SCT) was located at the head of the pancreas in a 43-year-old Japanese male, and pancreatoduodenectomy was performed on the suspicion of papillary carcinoma or cystadenocarcinoma of the pancreas. The lesion, which measured 4.5 X 4.5 X 4.0 cm, was clearly demarcated by connective tissue. The cut surface showed solid grayish-white areas with central cystic degenerative changes. The solid areas consisted of small round cells proliferating in a small solid or a pseudopapillary pattern. The tumor cells partially invaded the surrounding normal pancreatic parenchyma. Immunohistochemical studies revealed positive staining for alpha-1-antitrypsin and neuron-specific enolase, but no staining for known pancreatic hormones. Moreover, ultrastructural studies showed the absence of zymogen granules and the presence of anullate lamellae and neurosecretory granules. On the basis of these findings, a diagnosis of SCT of the pancreas was established. In order to clarify the histogenesis and biological behavior of the tumor, it is necessary to accumulate and analyze similar cases, an endeavor which in turn will contribute to the successful management of this disease. Acta Pathol Jpn 41: 763-770, 1991. 相似文献
27.
Tetsuya Makino Shohei Inoue Teiji Tsuruta 《Macromolecular chemistry and physics.》1970,131(1):147-167
Reactions of N-carboxy-α-amino acid anhydride (NCA) with dialkylzinc or related organozinc compounds were studied to elucidate the polymerization mechanism of NCA by dialkylzinc as initiator. The first stage of initiation reaction is a hydrogen abstraction reaction of dialkylzinc from NH group of α-amino acid NCA resulting in the formation of an activated NCA. The second stage of initiation is a reaction between two molecules of the activated NCA forming a zinc carbamate group. Propagation reaction is a carbonyl addition of the zinc carbamate group to the activated NCA to form a mixed anhydride which changes into an amide group releasing carbon dioxide. Regeneration of the activated NCA is supposed to be done by the reaction of free α-amino acid NCA with the zinc atom bonded to nitrogen atom at the growing chain end. 相似文献
28.
Teiji Tsuruta Kazuo Matsuura Shohei Inoue 《Macromolecular chemistry and physics.》1967,103(1):118-127
The copolymerization of N-carboxy-L(+)-alanine anhydride (L(+)-alanine NCA) with DL-propylene oxide was examined using diethylzinc or triethylaluminum as catalysts. Analytical data, IR and NMR-spectra indicate that dioxane soluble copolymers contain various kinds of linkage such as amide, ester, ether, and urethane in their polymer chains. Optical rotatory dispersion curves of the copolymers measured in benzene or chloroform were analyzed in terms of the one term DRUDE equation and of the MOFFITT-YANG equation. The copolymerization of L(-)-β-phenylallanine NCA with DL-propylene oxide was also examined. The sign of the optical rotation of the copolymer prepared with diethylzinc catalyst was opposite to that of the copolymer prepared with triethylaluminum. 相似文献
29.
Kuroiwa K Li H Tago K Iwahana H Yanagisawa K Komatsu N Oshikawa K Sugiyama Y Arai T Tominaga SI 《Hybridoma》2000,19(2):151-159
The human ST2 gene can be specifically induced by growth stimulation in fibroblastic cells, and can also be induced by antigen stimulation in Th2 cells. The gene encodes a soluble secreted protein, ST2, and a transmembrane protein, ST2L, which are closely related to the interleukin-1 receptor. To gain insight into the biological roles of the ST2 gene, three monoclonal antibodies (MAbs) against human ST2 gene products were obtained. To obtain these antibodies, immunization was carried out using two different immunogens: purified soluble human ST2 protein (hST2), and COS7 cells, which express the extracellular portion of human ST2L. 2A5 and FB9 MAbs were derived from the immunization with soluble hST2, and HB12 was derived from the COS7 cell immunization. All three antibodies were shown to detect native forms of the human ST2 gene products by immunoprecipitation, flow cytometry, and enzyme-linked immunosorbent assay (ELISA). In the competitive ELISA using biotinylated and nonlabelled MAbs, neither FB9 nor HB12 affected the binding of 2A5 to ST2 gene products. Based on this result, we constructed a sandwich ELISA system using 2A5 and FB9 to measure the concentration of soluble hST2 in sera. The ELISA, combined with the flow cytometry using these antibodies, will be a useful tool for elucidating the functions of human ST2 gene products in individuals. 相似文献
30.
N Yamaguchi Y Hitoshi S Takaki Y Murata M Migita T Kamiya J Minowada A Tominaga K Takatsu 《International immunology》1991,3(9):889-898
The murine interleukin 5 receptor (IL-5R) was identified by utilizing an immobilized IL-5 and an immobilized monoclonal antibody against the murein IL-5R (designated H7 mAb). The H7 mAb immunoaffinity-purified materials from the extract of cell-surface radioiodinated T88-M cells (an IL-5-dependent early B cell line) using 3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate (CHAPS) were reacted with an immobilized IL-5 matrix. SDS-PAGE of the adsorbed fraction revealed a single band at approximately 60 kDa. The binding of the 60 kDa protein to the immobilized IL-5 matrix was inhibited by the excess IL-5. The CHAPS-extract depleted of the 60 kDa protein by the absorption with H7 mAb did not contain any IL-5 binding proteins. Immunoaffinity procedure provided a final 7400-fold purification, based on an estimation of the content of the 60 kDa protein (approximate purity: 20%) from the silver-stained pattern of SDS-PAGE. Actin was copurified with the 60 kDa protein at an approximate ratio of 1:1, suggesting that the intracytoplasmic domain of the IL-5R may interact with actin. Furthermore, soluble IL-5R (molecular mass: 50 kDa) was purified by the H7 mAb-immunoaffinity chromatography. The purified soluble IL-5R was capable of inhibiting the binding of IL-5 to T88-M cells. Preparative SDS-PAGE followed by electroblotting onto a membrane permitted the determination of the N-terminal sequence of the IL-5R. The determined N-terminal sequence of the IL-5R and the deduced primary sequence from recently isolated cDNA were compared. 相似文献