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Biomedical subjects

H Fukui

Publications and source records attributed to H Fukui.

At least 361 records · Page 20Linked to original sources
PubMed1990

Molecular cloning of guinea-pig aromatic-L-amino acid decarboxylase cDNA.

Guinea-pig aromatic-L-amino acid decarboxylase (DOPA decarboxylase, DDC), but not rat DDC, reacts with the antibody against rat histidine decarboxylase (HDC). For determination of the molecular reaction for this cross-reactivity, a cDNA clone of guinea-pig DDC was isolated. Guinea-pig DDC consists of 480 amino acids and its molecular weight is 54,148. The sequence identify of guinea-pig DDC with rat DDC is 86%. Guinea-pig DDC has a region showing 100% sequence identity with rat HDC, but only 67% sequence identity with rat DDC, suggesting that this region is related with the cross-reactivity of guinea-pig DDC and anti-rat HDC antibody.

Amino Acid Sequence↗
PubMed1990

Characterization of a panel of monoclonal antibodies to human coagulation factor XI and detection of factor XI in Hep G2 cell conditioned medium.

We have produced a panel of ten monoclonal antibodies specific to coagulation factor XI. Western blot analysis demonstrates that 9 of these antibodies react with the heavy chain of factor XI and one with the light chain. Seven of these antibodies inhibit factor XI and factor XIa activity. We have used immobilised monoclonal antibody for the production of factor XI deficient plasma and to purify factor XI to homogeneity with high yield in a simple two-step procedure. These monoclonal antibodies were used to develop highly sensitive immunoassays capable of detecting less than 0.01 mu factor XI antigen ml-1. A strong correlation was found between antigen and activity levels in 11 patients with hereditary deficiency indicating that none was cross-reacting material positive. Cultured Hep G2 cells were found to synthesize small amounts of factor XI antigen and this could also be detected by functional assay and by western blot analysis.

Animals↗
PubMed1990

IL-6 activity in feline infectious peritonitis.

Involvement of IL-6 in the development of vasculitis and polyclonal gammopathy in feline infectious peritonitis (FIP) was investigated, by using the proliferative responses of two IL-6-dependent murine hybridoma cell clones, B3B1 and MH60.BSF-2 cells. A significant IL-6 activity was found in sera and ascitic fluids of cats with FIP, whereas no IL-6 activity was detected in sera from healthy cats. In these FIP cats, IL-6 activity in ascitic fluids was significantly higher than that in sera. Peritoneal exudate cells from FIP cats were also found to release a high level of IL-6 to the culture supernatant. The ascitic IL-6 activity was eluted into the fractions corresponding to the m.w. of 30,000 to 40,000 in gel filtration, and into the fractions at the salt concentration from 0.2 to 0.3 M NaCl in anion exchange chromatography. The level of ascitic IL-6 activity was inversely correlated to serum albumin/globulin ratio in these FIP cats. These findings indicate that IL-6 accumulated in the ascites might leaked into the systemic circulation, and be linked to systemic alterations such as enhanced synthesis of Ig and acute phase proteins.

Animals↗
PubMed1990

Enhanced botrocetin-induced type IIB von Willebrand factor binding to platelet glycoprotein Ib initiates hyperagglutination of normal platelets.

Botrocetin, a protein isolated from the venom of the snake Bothrops jararaca, induces platelet aggregation/agglutination by von Willebrand factor (vWF) binding to the membrane glycoprotein (GP) Ib, an action resembling that of ristocetin. However, some differences in the interaction between vWF and platelet GPIb induced by these two substances have been reported. We have recently shown that the GPIb binding domain on the vWF molecule, in both instances, resides in the tryptic 52/48 kDa fragment extending from amino acid residue 449 to 728 of the constituent subunit. In the present report, we demonstrate that botrocetin does not induce agglutination of formalin-fixed platelets from a patient with Bernard-Soulier syndrome congenitally lacking GPIb and GPIX as well as GPV, a finding similar to that shown with ristocetin. A monoclonal antibody against GPIb (AP-1) inhibits either ristocetin- or botrocetin-dependent vWF binding to formalin-fixed platelets from normal individuals. Therefore, botrocetin-induced vWF binding to formalin-fixed platelets may reflect the interaction between vWF and platelet GPIb. To strengthen this concept, we have now found that heightened botrocetin-induced type IIB vWF binding to platelet GPIb causes hyperagglutination of normal platelets.

Antibodies, Monoclonal↗
PubMed1990

Promoting effect of citrulline in hepatocarcinogenesis: possible mechanism in hypercitrullinemia.

Hypercitrullinemia (adult type), believed to be one of the hereditary urea cycle disorders, is known to be complicated by hepatocellular carcinoma at a high incidence (approximately 14%). We investigated the relationship between this hypercitrullinemia and hepatocarcinogenesis. After the addition of citrulline, incorporation of tritiated thymidine into primary cultured hepatocytes of adult rat increased in a dose-dependent fashion in the range of 0.1 to 5 mmol/L. The citrulline-added group also showed significant increase in ornithine and polyamine contents in hepatocytes. The incidence of epithelial cell foci in the in vivo-in vitro tumor promotion analyzing system significantly rose in the group maintained with 5 mmol/L citrulline and in the group maintained with 1.5 mmol/L phenobarbital. These findings suggest the possibility that citrulline has a promotion effect on hepatocyte proliferation and that at high concentrations it plays the role of a hepatocarcinogenesis promoter.

Amino Acids↗
PubMed1990

Effect of ethanol on hepatic oxygenation: evidence of hepatic hypoxia.

The effects of low (1 g/kg body wt) and high doses (4 g/kg body wt) of ethanol on hepatic oxygenation in rats was investigated employing an in vivo microscopic and spectrophotometric system and also a micro oxygen electrode. The low dose of ethanol increased sinusoidal blood hemoglobin oxygenation (ISO2) at periportal regions in the liver lobule. The high dose of ethanol increased ISO2 at periportal regions, but decreased ISO2 at pericentral regions. The low dose of ethanol increased hepatic surface tissue PO2, but the high dose decreased this PO2. From these data it is concluded that the increase of hepatic blood flow, after administration of a low dose of ethanol, compensated for the increase of oxygen demand in hepatocytes but that administration of a high dose of ethanol reduced hepatic tissue oxygenation via an imbalance between delivery and demand of oxygen in pericentral regions of the liver lobule, resulting in local hypoxia in surface hepatic tissue.

Animals↗
PubMed1990

Radioimmunoimaging of tumors with radioactive antibody against a glycoprotein (GP68) found in developing mouse brain.

The in vivo localization of a polyclonal antibody (pAb) against a glycoprotein with a molecular mass of 68 kDa (GP68), which was found in developing mouse brain, was studied in murine tumor models to evaluate potential applications of this antibody for in vivo radioimmunodetection and/or therapy of cancer. The tissue distribution of 125I-labeled GP68 pAb 3 days after i.v. injection into mice bearing four different kinds of solid tumor revealed a high uptake ratio by adenocarcinoma 755 and Lewis 3LL lung cancer. In contrast, the uptake ratio was low in mice bearing Ehrlich solid tumor and sarcoma-180 (S-180). These uptake ratios accorded well with the in vitro binding activity of this antibody with the tumor cells. In an immunoscintigraphic study, adenocarcinoma 755 was successfully visualized with 67Ga-labeled GP68 pAb. The results of these biodistribution and in vivo radioimmunoscintigraphic studies suggest that GP68 antibody may be applicable to the diagnosis and/or therapy of cancer.

Adenocarcinoma↗
PubMed1990

Biotransformation of 18 beta-glycyrrhetinic acid by cell suspension cultures of Glycyrrhiza glabra.

Two biotransformation products formed from 18 beta-glycyrrhetinic acid by cell suspension cultures of Glycyrrhiza glabra were isolated and their structures determined by chemical and spectral data as 3-O-[alhpa-L-arabinopyranosyl-(1----2)-beta-D-Glucuronopy ranosyl]-24- hydroxy-18 beta-glycyrrhetinic acid and 30-O-beta-D-glycopyrano-syl-18 beta-glycyrrhetinic acid. The formation of glycyrrhizin, the main triterpene glucuronide of the licorice root, was not detected among the biotransformation products. This is the first report of the glucuronylation of an exogenous triterpene in plant cell cultures.

Biotransformation↗
PubMed1990

Purification and characterization of soluble human IL-6 receptor expressed in CHO cells.

An immunosorbent assay system to detect genetically engineered IL-6 receptor (IL-6R) was established, whereby soluble IL-6 receptor (sIL-6R) was detected in the culture medium when sIL-6R cDNA was transfected into COS1 cells. A stably transformed Chinese hamster ovary (CHO) cell line constitutively expressing sIL-6R has been established. The recombinant sIL-6R was purified to homogeneity by sequential filtration and chromatography of the culture medium. The recombinant sIL-6R augmented the sensitivity of M1 cells to IL-6 in growth inhibition assay in a dose-dependent manner. Furthermore, a radioisotope immunosorbent assay (RIA) utilizing recombinant sIL-6R was established which could detect IL-6 in a quantity as low as 10 ng/ml.

Amino Acid Sequence↗
PubMed1990

Immunologic abnormality in NZB/W F1 mice. Thymus-independent expansion of B cells responding to interleukin-6.

We have previously reported that B cell abnormality in NZB/W F1 mice developed independently of thymus. Here we examined further whether B cells from NZB/W F1 mice respond to interleukin-6 (IL-6), a factor for terminal differentiation of B cells. When freshly isolated splenic B cells were incubated for 5 days in the presence of human IL-6, an increased production of both IgM and IgG, including anti-DNA antibody, was evident in NZB/W F1 mice; there was no increase in BALB/c mice. A magnitude of augmentation in IgG but not IgM production by IL-6 became more apparent in older NZB/W F1 mice. The increased immunoglobulin production seen with IL-6 was neutralized by treatment with rabbit anti-recombinant human IL-6 antibody. As B cells from athymic NZB/W F1 nude mice also responded to IL-6, it was suggested that B cells in NZB/W F1 mice differentiated into the IL-6-responding state in a thymus-independent manner. This B cell abnormality may be associated with the pathogenesis of autoimmune disease in NZB/W F1 mice.

Animals↗
PubMed1990

[Pharmacological studies of celiprolol: III. Effects of celiprolol on the cardiovascular system and renal function, and its antiarrhythmic effects].

Effects of celiprolol on the cardiovascular system and renal function, and its antiarrhythmic effects were studied. 1. In anesthetized dogs, celiprolol (0.01-3 mg/kg, i.v.) dose-dependently depressed the maximum rate of rise of left ventricular pressure, cardiac output and cardiac work less severely than propranolol and atenolol. 2. Celiprolol (0.01 mg/kg, i.v.) decreased the myocardial oxygen consumption in anesthetized dogs as potently as propranolol. 3. Celiprolol (0.03-3 mg/kg, i.v.) tended to increase femoral blood flow. Celiprolol (1 mg/kg, i.v.) increased common carotid blood flow. 4. Celiprolol decreased urine volume and urinary excretion of Na+ and Cl- at doses of 1 and 10 mg/kg and increased the sodium reabsorption rate at a dose of 10 mg/kg in anesthetized dogs, whereas it produced no change in plasma renin activity. 5. Celiprolol inhibited both halothane-adrenaline arrhythmia in dogs and ouabain-induced arrhythmia in rabbits. Its antiarrhythmic effects were 1/10-1/3 as potent as those of propranolol. 6. Celiprolol suppressed the maximum rate of rise of action potential at a concentration of 3 x 10(-4) M, which was 30 times as high as that of propranolol. Celiprolol (3 x 10(-5)-3 x 10(-4) M) dose-dependently shortened the effective refractory period (ERP), but it produced no change in the ratio of ERP to action potential duration. 7. These results suggest that celiprolol may be a useful drug for the treatment of ischemic heart disease and some types of arrhythmia, and that it has only a little influence on renal function.

Action Potentials↗
PubMed1990

Comparative studies on soy protein and rice protein for cholesterol metabolism in rats.

The serum level of cholesterol in rats fed a diet containing soy protein isolate was lower than that in rats fed either casein or rice protein at the level of 15% even after one day feeding, although fecal excretion of bile acids of rats fed soy protein isolate was almost equal with that of rats fed rice protein. Similar effect was also observed in the secretion rate of lipoproteins from the liver. Dietary proteins may affect the synthesis of apolipoproteins directly or through the hormonal system.

Absorption↗
PubMed1990

[Immunohistological demonstration of developmental protein GP68 in human tumor and embryonic tissues].

A developmental protein GP68 is known to appear stage-specifically in the developmental mouse brain. The expression of GP68 in tissues of 265 various human tumors and of 2 human embryos was examined immunohistologically using specific anti-GP68 rabbit antisera. Generally, endodermal, neural, and germ cell tumors were most frequently positive, while mesenchymal tumors were mostly and ectodermal tumors were intermediate. Anti-GP68 also gave positive reactions with some of non-neoplastic cells of cancer patients generally to lesser extents than neoplastic cells. Muscle and bone tissues of a 4-week-old embryo were weakly positive. Some tumors that were negative for CEA and AFP were strongly positive for GP68. The expression of GP68 in human tumor cells may represent an abnormal cellular gene-expression associated with the neoplastic change of the cell.

Carcinoembryonic Antigen↗
PubMed1990

[Evaluation of intrahepatic distribution of inferior mesenteric blood flow by transrectally administered 123I-IMP].

Intrahepatic distribution of the inferior mesenteric blood flow was evaluated with scintigraphy with transrectally administered 123I-iodoamphetamine (IMP). Twelve patients without liver diseases were studied. The IMP image was divided into 3 types; bilateral, left lobar predominant and right lobar predominant. Bilateral, left lobar predominant and right lobar predominant types were observed in 5, 5 and 2 patients respectively. Furthermore, uneven distribution pattern in the left or right lobe was observed in 2 of 5 patients with bilateral lobar type, 4 of 5 patients with left lobar predominant type and 1 of 2 patients with right lobar predominant type. In one patient with left lobar predominant type, repeat examination demonstrated bilateral lobar type. These results suggest that intrahepatic distribution of the inferior mesenteric blood flow is not uniform and consistent.

Administration, Rectal↗