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N Shibata

Publications and source records attributed to N Shibata.

At least 253 records · Page 14Linked to original sources
PubMed1992

Structural study of a cell wall mannan-protein complex of the pathogenic yeast Candida glabrata IFO 0622 strain.

We conducted a structural analysis of the cell wall mannan-protein complex (mannan) isolated from a pathogenic yeast, Candida glabrata IFO 0622 strain. The chemical structure of mannobiose released from this mannan by treatment with 10 mM HCl at 100 degrees C for 1 h was identified as Manp beta 1-2Man. The treatment of this mannan with 100 mM NaOH at 25 degrees C for 18 h gave a mixture of alpha-1,2- and alpha-1,3-linked oligosaccharides, from tetraose to biose, and mannose. The acid- and alkali-stable mannan moiety was subjected to mild acetolysis with a 100:100:1 (v/v) mixture of (CH3CO)2O, CH3COOH, and H2SO4 at 40 degrees C for 36 h. The resultant three novel oligosaccharides, tetraose, hexaose, and heptaose, were identified as Manp beta 1-2Manp alpha 1-2Manp alpha 1-2Man, Manp alpha 1-2Manp alpha 1-2Manp alpha 1-6Manp alpha 1-2Manp alpha 1-2Man, and Manp alpha 1-3Manp alpha 1-2Manp alpha 1-2Manp alpha 1-6Manp alpha 1- 2Manp alpha 1-2Man, respectively, in addition to the three known oligosaccharides, Manp alpha 1-2Man, Manp alpha 1-2Manp alpha 1-2Man, and Manp alpha 1-3Manp alpha 1-2Manp alpha 1-2Man. A sequential analytical procedure involving partial acid hydrolysis with hot 0.3 M H2SO4, methylation, fast atom bombardment mass, and 1H NMR analyses was quite effective in the structural determination of the novel oligosaccharides. The results indicate that this mannan possesses a structure closely resembling that of Saccharomyces cerevisiae X2180-1A wild type strain, with the presence of small amounts of oligomannosyl residue, Manp beta 1-2Manp alpha 1-X, corresponding to one of the epitopes dominating serotype-A specificity of Candida spp., in addition to branches corresponding to hexaose and heptaose each containing one intermediary alpha-1,6 linkage.

Candida↗
PubMed1992

Diphosphorylation of platelet myosin by myosin light chain kinase.

Recently, one of the authors (K.I.) and other investigators reported that myosin light chain (MLC) of smooth muscle (gizzard, arterial and tracheal) was diphosphorylated by myosin light chain kinase (MLCK) and that diphosphorylated myosin showed a marked increase in the actin-activated myosin ATPase activity in vitro and ex vivo. In this study, we prepared myosin, actin, tropomyosin (human platelet), MLCK (chicken gizzard) and calmodulin (bovine brain) and demonstrated diphosphorylation of MLC of platelet by MLCK in vitro. Our results are as follows. (1) Platelet MLC was diphosphorylated by a relatively high concentration (greater than 20 micrograms/ml) of MLCK in vitro. As a result of diphosphorylation, the actin-activated myosin ATPase activity was increased 3 to 4-fold as compared to the monophosphorylation. (2) Both di- and monophosphorylation reactions showed similar Ca2+, KCl, MgCl2-dependence. Maximal reaction was seen at [Ca2+] greater than 10(-6) M, 60 mM KCl and 2 mM MgCl2. This condition was physiological in activated platelets. (3) Di- and monophosphorylated myosin showed similar Ca2+, KCl-dependence of ATPase activity but distinct MgCl2-dependence. Diphosphorylated myosin showed maximal ATPase activity at 2 mM MgCl2 and monophosphorylated myosin showed a maximum at 10 mM MgCl2. (4) The addition of tropomyosin stimulated actin-activated ATPase activity in both di- and monophosphorylated myosin to the same degree. (5) ML-9, a relatively specific inhibitor of MLCK, inhibited the aggregation of human platelets induced by thrombin ex vivo in a dose-dependent manner. Moreover, this drug also partially inhibited both di- and monophosphorylation reactions and actin-activated ATPase activity. On the other hand, H-7, a synthetic inhibitor of protein kinase C, had little effect on the aggregation of human platelets induced by thrombin ex vivo. From these results, we conclude that diphosphorylation of platelet myosin by MLCK may play an important role in activated platelets in vivo.

Actins↗
PubMed1992

Localization of laminin in nephritic glomeruli as revealed by a quick-freezing and deep-etching method with immunohistochemistry.

The three-dimensional localization of laminin in rat glomeruli at the chronic phase of Masugi nephritis was investigated by a quick-freezing and deep-etching method combined with immunohistochemistry. Light-microscopically, laminin was localized in increased mesangial matrix and thickened glomerular basement membrane. The quick-freezing and deep-etching method revealed that the increased mesangial matrix, which was newly formed in axial portions and areas of mesangial interposition, was composed of fine fibrillar networks. They were revealed with the 3,3'-diaminobenzidine tetrahydrochloride (DAB) reaction products of peroxidase-labelled secondary antibody following anti-laminin antibody. However, these reaction products were not uniformly distributed in the newly formed matrix. Although the fibrils organizing lamina densa were also immunostained with anti-laminin antibody, the fibrils connected to mesangial cells, podocytes and endothelial cells had smaller amounts of DAB reaction products for laminin. These results indicate that one of the components of fibrils in the mesangial matrix and lamina densa is laminin, which is heterogeneously distributed in the newly formed matrix.

3,3'-Diaminobenzidine↗
PubMed1992

Structural study of cell wall mannan of a Candida albicans (serotype A) strain.

The structure of the mannan of Candida albicans NIH A-207 strain (serotype A) was investigated by adopting mild acetolysis followed by enzymolysis with an Arthrobacter GJM-1 exo-alpha-mannosidase. The resultant oligosaccharides, from pentaose to octaose (where manp = D-mannopyranose), were identified as manp beta (1----2)manp alpha (1----2)manp alpha (1----2)manp alpha (1----2)manp, manp beta (1----2)manp beta (1----2)manp alpha (1----2)manp alpha (1----2)- manp alpha (1----2)manp, manp beta (1----2)manp beta (1----2)manp beta (1----2)manp alpha (1----2)manp alpha (1----2)manp alpha (1----2)manp and manp beta (1----2)manp beta (1----2)manp beta (1----2)manp beta (1----2)manp alpha (1----2)manp alpha (1----2)manp alpha (1----2)manp, respectively. Analyses of alpha-linked oligosaccharides obtained by acetolysis under conventional conditions gave the same oligosaccharides, from biose to heptaose, as those obtained from the mannans of C. albicans NIH B-792 (serotype B) and J-1012 (serotype A, formerly serotype C).

Candida albicans↗
PubMed1992

Foreign gene expression by a baculovirus vector with an expanded host range.

A nuclear polyhedrosis virus (NPV) (Baculoviridae)-based gene expression system was improved by DNA recombination. The BmN cell line established from Bombyx mori and the Sf21 cell line established from Spodoptera frugiperda are non-permissive for Autographa californica multicapsid NPV (AcMNPV) and B. mori NPV (BmNPV) replication, respectively. After cotransfection of AcMNPV DNA and BamHI-digested BmNPV DNA into Sf21 cells, progeny viruses were isolated by plaque purification on BmN cell monolayers and the host specificity of one viral isolate was analysed. The virus had a wider host range, and replicated and produced polyhedra in Sf21 cells, BmN cells and larvae of the silkworm, B. mori. DNA restriction endonuclease analysis showed that the isolate was a hybrid of AcMNPV and BmNPV. Using the AcMNPV transfer vector pAcYM1 a portion of the polyhedrin gene of the hybrid virus was replaced with the coding region of the firefly luciferase gene, producing a recombinant virus. The latter expressed firefly luciferase in both cell lines and in silkworm larvae under the control of the polyhedrin promoter.

Baculoviridae↗
PubMed1992

Structural identification of an epitope of antigenic factor 5 in mannans of Candida albicans NIH B-792 (serotype B) and J-1012 (serotype A) as beta-1,2-linked oligomannosyl residues.

In previous articles, we reported the presence of phosphate-bound beta-1,2-linked oligomannosyl residues in the mannans of strains of Candida albicans serotypes A and B and Candida stellatoidea. To identify the antigenic factor corresponding to this type of oligomannosyl residue, a relationship between chemical structure and antigenic specificity in the mannans of C. albicans NIH B-792 (serotype B, B-strain) and C. albicans J-1012 (serotype A, J-strain) was investigated by using a combination of two-dimensional 1H nuclear magnetic resonance spectroscopy of H-1, H-2, and H-5 regions in the mannans and an enzyme-linked immunosorbent assay that employed concanavalin A-coated microtiter plates. It was shown in the present 1H nuclear magnetic resonance study that an examination of chemical shifts not only in the H-1 region but also in the H-5 region was useful for the quantitative determination of the phosphate-bound beta-1,2-linked oligomannosyl residues. In the enzyme-linked immunosorbent assay using concanavalin A-coated plates, it was revealed that, of factor sera 1, 4, and 5, only factor serum 5 showed a reactivity proportional to the densities of the beta-1,2-linked oligomannosyl residues of the mannan subfractions of different phosphate contents that had been prepared from the bulk B-strain mannan by DEAE-Sephadex chromatography. The above results indicate that the phosphate-bound beta-1,2-linked oligomannosyl residues, Manp beta 1----(2Manp beta 1----)n2Man (n = 0-5), correspond to antigenic factor 5.

Antigens, Fungal↗
PubMed1992

Evidence for oligomannosyl residues containing both beta-1,2 and alpha-1,2 linkages as a serotype A-specific epitope(s) in mannans of Candida albicans.

In order to identify the branches containing both beta-1,2 and alpha-1,2 linkages as the serotype A-specific epitope(s) in the mannans of Candida albicans, serotype A strains with oligosaccharides constituting the beta-1,2 linkage, the alpha-1,2 linkage, and both the beta-1,2 and the alpha-1,2 linkages were prepared from the mannans of C. albicans serotype A strains (NIH A-207 and J-1012) and tested for their inhibitory effects in the precipitin and slide agglutination assays. The results indicated that two oligosaccharides containing both beta-1,2 and alpha-1,2 linkages, Manp beta 1-2Manp alpha 1-2Manp alpha 1-2Manp alpha 1-2Man and Manp beta 1-2Manp beta 1-2Manp alpha 1-2Manp alpha 1-2Manp alpha 1-2Man, served as epitopes participating in the serotype A specificity of C. albicans strains.

Agglutination↗
PubMed1992

[Effect of tranilast, an anti-allergic drug, on the human keloid tissues].

We studied the inhibitory effects of tranilast, an anti-allergic drug, on the human keloid tissues implanted into the dorsal skin of athymic nude mice and on the growth of keloid fibroblast in vitro. In the keloid tissue-implanted model, tranilast (50-200 mg/kg, p.o.) decreased the weight of the keloid tissue as triamcinolone (25 mg/kg, p.o.) did. Tranilast (200 mg/kg, p.o.) reduced the hydroxyproline content of implanted tissues. Tranilast (3-300 microM) also inhibited the collagen synthesis by keloid fibroblast in vitro. Only a high concentration of tranilast (300 microM) suppressed the glycosaminoglycan synthesis and cell proliferation of keloid fibroblasts. Moreover, tranilast scarcely affected the fibronectin production. Triamcinolone (10 microM) also inhibited glycosaminoglycan synthesis and cell proliferation. These results suggest that the inhibitory effect of tranilast on the keloid tissues is related to its inhibition of the collagen synthesis of fibroblasts. Tranilast would be useful as a therapeutic drug for the treatment of keloids.

Animals↗
PubMed1992

[Clinical experience of a percutaneous ventricular support for profound heart failure following acute myocardial infarction--a case report].

Percutaneous biventricular support with centrifugal pump was applied to a 59-year-old man with profound heart failure following acute myocardial infarction. Direct coronary angioplasty was performed under percutaneous cardiopulmonary support (PCPS). After angioplasty, he could not be weaned from PCPS under IABP. We used percutaneous left ventricular support (PLVS) with transseptal left atrial cannulation. PLVS could not maintain effective assist flow and he developed a cardiogenic shock again. PCPS was added to PLVS, and percutaneous biventricular support was started. Assist flow ranged 1.7-3.0 L/min in PLVS, and 1.7-2.0 L/min in PCPS, and total assist flow was 3.4 L/min. Pulsatile pressure was obtained by adding IABP. The patient was successfully weaned from PCPS in 26 hours and PLVS in 118 hours. Patient is alive and well one year after PLVS. Combination of PLVS and PCPS is an effective ventricular support system, being less invasive than conventional method with thoracotomy, and may be useful for profound heart failure.

Heart Failure↗
PubMed1992

[A case report of complete remission of liver metastasis from rectal carcinoma treated with intra-arterial infusion chemotherapy].

We reported a case of metastatic liver cancer from rectal carcinoma, which was successfully treated by systemic continuous 5-Fluorouracil and intermittent Mitomycin C chemotherapy. A 70-year-old male with rectosigmoid carcinoma was admitted to our hospital. Abdominal CT and echography revealed solid mass in the liver. He underwent low anterior resection and infuse-a-port was inserted because of arterial infusion chemotherapy for metastatic liver cancer. 5-FU (250 mg per day) was infused continuously and MMC at the dose of 8 mg for one time in a week was administered. Two months later, hepatic tumor disappeared and the serum CEA level also normalized. At this writing, the patient is alive and well and complete remission has been obtained for more than 10 months.

Adenocarcinoma↗
PubMed1992

[Isolated angiitis of the CNS associated with Hashimoto's disease].

In 1987, a 69-year-old female suffering from epilepsy and right hemiparesis was admitted to the hospital and given conservative therapy. During the next three weeks she became a stuporous state. Steroids were then prescribed, and she made a complete recovery. Following hormonal and immunological investigations, a diagnosis of Hashimoto's disease with hypothyroidism was made. Following her discharge, thyroxin and anticonvulsant treatments continued. On May 30, 1989, at the age of seventy-one, the patient was found lying unconscious at home, and taken to our hospital. She had signs of a confused state, and seizures of her right arm on admission. Cranial computed tomography (CT) revealed a low density area in the left parieto-occipital lobe, which was heterogeneously enhanced by contrast medium. Magnetic resonance imaging (MRI) showed a lesion of low signal intensity in T1-weighted images and high signal intensity in T2-weighted images, which was homogeneously enhanced by Gd DTPA. Cerebral angiography disclosed no abnormality. Two weeks later, follow-up CT showed that the lesion had become larger and markedly enhanced. A brain tumor, probably malignant lymphoma, was suspected. On June 14, stereotaxic biopsy of the enhanced lesion was performed. Histopathological examination disclosed dense infiltration of the entire walls of many small parenchymal vessels, both arterioles and venules, by lymphocytes. Treatment for angiitis (betamethasone 16 mg daily) was started on June 20, then gradually tapered, and the lesion diminished on CT. Our case has some features of both isolated angiitis of the central nervous system and encephalopathy in compensated Hashimoto's disease. It is suggested that some common base of the autoimmune diseases exists in this case.

Aged↗
PubMed1992

Detection of abnormal cardiac adrenergic neuron activity in adriamycin-induced cardiomyopathy with iodine-125-metaiodobenzylguanidine.

Radiolabeled metaiodobenzylguanidine (MIBG), an analog of norepinephrine (NE), serves as an index of adrenergic neuron integrity and function. Using a rat model of adriamycin-induced cardiomyopathy, we tested the hypothesis that abnormal cardiac adrenergic neuron activity may appear and be exacerbated dose-dependently in adriamycin cardiomyopathy. The degree of vacuolar degeneration of myocardial cells was analyzed in relation to the duration of adriamycin treatment (2 mg/kg, once a week). There were no abnormalities or only isolated degeneration in the 1- or 2-wk treatment groups, isolated or scattered degeneration in half of the 3-wk group, frequent scattered degeneration in the 4-wk group, scattered or focal degeneration in the 5-wk group, and extensive degeneration in the 8-wk group. Myocardial accumulation of [125I]MIBG 4 hr after intravenous injection did not differ between the controls and the groups treated 3 wk or less. However, the 4-wk group had a slightly lower accumulation in the right ventricular wall (82% of the control) and significantly lower accumulation in the left ventricular wall (about 66% of the control: p less than 0.05). In the 5-wk group, MIBG accumulation in the right and left ventricular wall was 35% and 27% of that in controls, respectively (p less than 0.001). In the 8-wk group, MIBG accumulation in the right and left ventricular wall was 18% and 14% of that in controls, respectively (p less than 0.001). Thus, MIBG accumulation in the myocardium decreased in an adriamycin dose-dependent manner. The appearance of impaired cardiac adrenergic neuron activity in the presence of slight myocardial impairment (scattered or focal vacuolar degeneration) indicates that MIBG scintigraphy may be a useful method for detection of adriamycin-induced cardiomyopathy.

3-Iodobenzylguanidine↗
PubMed1991

Structural study on a phosphorylated mannotetraose obtained from the phosphomannan of Candida albicans NIH B-792 strain by acetolysis.

A mixture of phosphorylated manno-oligosaccharides was isolated from the acid-stable domain of phosphomannan of Candida albicans NIH B-792 strain (serotype B) by acetolysis and was fractionated on a column of Bio-Gel P-2 equilibrated with 50 mM pyridine-CH3COOH buffer, pH 5.0. A monophosphorylated mannotetraose was isolated as the major constituent. Structural analyses of this phosphate-containing tetraose and its reduction product with NaBH4 by 1H, 13C, and two-dimensional homonuclear Hartmann-Hahn NMR spectroscopies, subsequently, gave results consistent with the structure described below (where Manp represents the mannopyranose unit): [formula: see text] It was unexpected that the major phosphorylated branch in the acid-stable domain of the parent phosphomannan of this C. albicans strain is a relatively short mannotetraosyl residue containing solely alpha-1,2-linked mannopyranose units, and a phosphate group as a 6-O-ester on the intermediary unit adjacent to the nonreducing terminal group. These findings indicate that the size of the major phosphorylated branch of this phosphomannan is the same as that of Saccharomyces cerevisiae.

Candida albicans↗
PubMed1991

Structural determination of D-mannans of pathogenic yeasts Candida stellatoidea type I strains: TIMM 0310 and ATCC 11006 compared to IFO 1397.

The structures of the cell-wall D-mannans of pathogenic yeasts of Candida stellatoidea Type I strains, IFO 1397, TIMM 0310, and ATCC 11006, were investigated by mild acid and, alkaline hydrolysis, by digestion with the Arthrobacter GJM-1 strain exo-alpha-D-mannosidase, and by acetolysis. The modified D-mannans and their degradation products were studied by 1H- and 13C-n.m.r. analyses. D-Manno-oligosaccharides released by acid treatment from the parent D-mannans were identified as the homologous beta-(1----2)-linked D-manno-oligosaccharides from biose to hexaose, whereas those obtained by alkaline degradation were the homologous alpha-(1----2)-linked D-mannobiose and D-mannotriose. The acid- and alkali-modified D-mannans lacking 1H-n.m.r. signals above 4.900 p.p.m. [corresponding to beta-(1----2)-linked D-mannopyranose units] were acetolyzed with 10:10:1 (v/v) Ac2O-AcOH-H2SO4, and the resultant D-manno-oligosaccharides were also analyzed. It was found that the longest branches of these D-mannans, corresponding to hexaosyl residues, had the following structures: alpha-D-Manp-(1----3)-alpha-D-Manp-(1----2)-alpha-D-Manp+ ++-(1----2)-alpha-D-Manp- (1----2)-alpha-D-Manp-(1----2)-D-Man and alpha-D-Manp-(1----2)-alpha-D-Manp-(1----3)-alpha-D-Manp+ ++-(1----2)-alpha-D-Manp- (1----2)-alpha-D-Manp-(1----2)-D-Man. These results indicate that the D-mannans of C. stellatoidea Type I strains possess structures in common with the D-mannans of Candida albicans serotype B strain (see ref. 4) containing phosphate-bound beta-(1----2)-linked oligo-D-mannosyl residues.

Candida↗
PubMed1991

Fluorimetric determination of mexiletine in serum by high-performance liquid chromatography using pre-column derivatization with fluorescamine.

A simple, specific and sensitive micro-scale method for the assay of the antiarrhythmic agent mexiletine in human serum is described. The method uses high-performance liquid chromatography, with pre-column fluorimetric derivatization by fluorescamine. Following extraction with diethyl ether, mexiletine and 4-methylmexiletine (an internal standard) were derivatized with fluorescamine under weakly alkaline condition (pH 9.0) and chromatographed on a reversed-phase column with aqueous methanol-2-propanol as the mobile phase. The two fluorescent derivatives of mexiletine and the internal standard were separated as clear single peaks, and no interfering peaks were observed on the chromatograms. The detection limit for mexiletine was 0.005 micrograms/ml from only 100 microliters of serum, and the calibration curves in the range 0.01-5 micrograms/ml were linear, with an overall coefficient of variation of less than 5%. The analytical recovery of a known amount of mexiletine added to serum was almost 100%. This method proved to be effective in the rapid monitoring of the serum concentrations in patients who received this potent antiarrhythmic drug.

Anti-Arrhythmia Agents↗
PubMed1991

Candida albicans serotype A strains grow in yeast extract-added Sabouraud liquid medium at pH 2.0, elaborating mannans without beta-1,2 linkage and phosphate group.

Cultivation of three Candida albicans strains, NIH A-207, J-1012, and NIH B-792, abbreviated as A-, J-, and B-strains, respectively, in yeast extract-enrich Sabouraud liquid medium at pH 2.0 provided the following findings, i.e., the two former strains belonging to serotype A were able to grow in this medium in almost the same rates as those in the same medium of pH 5.9, while B-strain cells did not proliferate under the former condition. The cells of A- and J-strains cultivated at pH 2.0 did not undergo agglutination with the factor serum 6 in a commercially available factor serum kit, Candida Check, corresponding to C. albicans serotype A-specific epitope. It was also revealed by 1H-13C correlation spectra of the mannans isolated from the cells of A- and J-strains contained neither phosphate group nor beta-1,2-linked mannopyranose unit, although these mannans retained non-reducing terminal alpha-1,3 linked mannopyranose units, providing a substantiating evidence that the serotype A-specific epitope contains a non-reducing terminal beta-1,2-linked mannopyranose unit.

Candida albicans↗