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Biomedical subjects

E Ito

Publications and source records attributed to E Ito.

At least 253 records · Page 14Linked to original sources
PubMed1988

Histopathological studies of experimental marine toxin poisoning. II. The acute effects of maitotoxin on the stomach, heart and lymphoid tissues in mice and rats.

Maitotoxin, one of the causative agents of ciguatera isolated from marine dinoflagellate, Gambierdiscus toxicus, induced severe pathomorphological changes in the stomach, heart and lymphoid tissues in mice and rats. Multiple erosions were observed in gastric mucosa accompanied by a marked increase in total calcium content 24 hr after i.p. injection of 200 or 400 ng/kg of maitotoxin. In contrast, there was no close temporal association between the accumulation of calcium and the morphological appearance of dead cells in the heart and thymus. Within 30 min of administration of 200 or 400 ng/kg of maitotoxin, a marked swelling was seen in the endothelial lining cells of blood capillaries between cardiac muscle fibers, followed by the cell death of the fibers. Injection of maitotoxin at a dose of 200 ng/kg or higher also resulted in necrosis of lymphocytes in the cortex of the thymus at 4 hr and in the medulla at 8 hr.

Animals↗
PubMed1988

Structure of the O-polysaccharide chain of lipopolysaccharide from Pseudomonas aeruginosa IID 1001 (ATCC 27577).

Structural studies were carried out on an acidic O-polysaccharide released by mild acid treatment from the lipopolysaccharide of Pseudomonas aeruginosa IID 1001 (ATCC 27577), which is serologically related to the serotypes Habs O3, Lanyi O1, and Wokatsch O13 in other serological classifications of Pseudomonas aeruginosa. The composition and data from structural analyses including H-NMR and C-NMR measurements, methylation, and Smith degradation showed that the structure of the IID 1001 O-polysaccharide was coincident with that of the Habs O3 and Lanyi O1 antigens (or Wokatsch O13). However, whereas solvolysis of the O-antigen of Habs O3 as well as that of Lanyi O1 by hydrogen fluoride has been reported to yield a reducing trisaccharide, GlcNAc(alpha 1----4)GalNAcA(alpha 1----3)Bac2NAc4Nacyl (acyl represents a 3-hydroxybutanoyl group), hydrogen fluoride hydrolysis of IID 1001 O-polysaccharide yielded a nonreducing trisaccharide with the reducing terminal bacillosamine residue linked at C-1 to the hydroxyl group of its N-acyl substituent, 3-hydroxybutanoic acid. These results, in combination with mass spectral data, led to the most likely structure for the tetrasaccharide repeating unit of the IID 1001 O-polysaccharide, (formula; see text) in which the location of N-acyl groups on bacillosamine residues differs from that in the O-antigens of Habs O3 and Lanyi O1 (or Wokatsch O13).

Lipopolysaccharides↗
PubMed1988

Partial purification and properties of UDP-N-acetylmannosamine:N-acetylglucosaminyl pyrophosphorylundecaprenol N-acetylmannosaminyltransferase from Bacillus subtilis.

An enzyme which catalyzes the conversion of GlcNAc-PP-undecaprenol into ManNAc(beta 1----4)GlcNAc-PP-undecaprenol, a key lipid intermediate in the de novo synthesis of various teichoic acids, was partially purified from the 20,000 x g supernatant fraction of Bacillus subtilis AHU 1035 cell homogenate. By means of ammonium sulfate precipitation, gel chromatography, and ion-exchange chromatography, the enzyme was purified about 70-fold, giving a preparation virtually free from substances obstructive to measurement of the N-acetylmannosaminyltransferase reaction. The enzyme was shown to be specific to UDP-ManNAc. The Km value for UDP-ManNAc was 4.4 microM, and the optimum pH was 7.3. The enzyme required 10 mM MgCl2, 0.3 M KCl, 25% glycerol, and 0.1% Nonidet P-40 to function at full activity.

Bacillus subtilis↗
PubMed1988

Solubilization and properties of UDP-D-glucose:N-acetylglucosaminyl pyrophosphorylundecaprenol glucosyltransferase from Bacillus coagulans AHU 1366 membranes.

The glucosyltransferase which catalyzes the conversion of GlcNAc-PP-undecaprenol into Glc(beta 1----4)GlcNAc-PP-undecaprenol in the presence of UDP-glucose was solubilized from Bacillus coagulans AHU 1366 membranes by treatment with 0.1% Triton X-100 and partially purified by means of column chromatography on Sephacryl S-300 and DEAE-Sephacel. The final preparation was virtually free from other enzymes involved in the de novo synthesis of teichoic acid. The enzyme had a pH optimum of 6.6-8.0 and a Km value for UDP-glucose of 21 microM. The enzyme required 40 mM MgCl2, 0.6 M KCl, and 0.1% Nonidet P-40 for full activity.

Bacillus↗
PubMed1988

Insulin resistance in a boy with congenital generalized lipodystrophy.

We have studied insulin resistance in a 12-year-old Japanese boy who presented with congenital generalized lipodystrophy. Oral glucose tolerance test exhibited a diabetic pattern with normal fasting plasma glucose. Results from euglycemic glucose clamp study showed decreases in both insulin sensitivity and responsiveness. Both the patient's erythrocytes and Epstein-Barr virus transformed lymphocytes showed low-normal insulin binding with a slight reduction in binding affinity in the latter. Insulin binding to the cultured fibroblasts was decreased due to a lowered affinity. In addition, they displayed a rightward shift of the insulin dose-response curve for D-14C-glucose uptake with no decrease in the maximum uptake. Insulin-stimulated autophosphorylation and kinase activity of the wheat germ agglutinin purified receptors from the Epstein-Barr virus-transformed lymphocytes appeared normal. The reason for some discrepancies in insulin binding among the cells remains unknown, and we cannot formulate a conclusion as to whether or not a primary binding defect of insulin receptors exists and contributes to insulin resistance in the patient. The decrease in insulin responsiveness demonstrated in the glucose clamp study may result from a defect at the rate-limiting step in the postbinding process of insulin action, presumably a defect in the glucose transport system in muscle tissues. The defect may be secondary to changes in in vivo circumstances.

Cell Line, Transformed↗
PubMed1988

[Bladder irrigation with prostaglandin E2 in cyclophosphamide-induced hemorrhagic cystitis].

A four-year-old boy with stage IV neuroblastoma was treated using the group study protocol of the Tohoku area for advanced neuroblastoma, consisting of DTIC, CPA, VCR, CDDP and VM-26, as a result of which had obtained complete remission. However, he had severe hemorrhagic cystitis after administration of CPA. He was treated with the usual therapy, but symptoms such as hematuria, pollakiuria and miction pain were not improved. We then tried bladder irrigation with prostaglandin E2. Half a milligram of PGE2 in 100 ml of physiological saline solution was instilled into the bladder and left in situ for 3 hours. The patient was free of symptoms on the day following the therapy. Local therapy with PGE2 thus seems very useful for cyclophosphamide-induced cystitis.

Administration, Intravesical↗
PubMed1987

Characterization of a polysaccharide component of lipopolysaccharide from Pseudomonas aeruginosa IID 1008 (ATCC 27584) as D-rhamnan.

Structural studies were carried out on a rhamnose-rich polysaccharide isolated from the O-polysaccharide fraction of lipopolysaccharide in Pseudomonas aeruginosa IID 1008 (ATCC 27584) after destruction of the major O-specific chain by alkaline treatment. The isolated polysaccharide contained rhamnose, 3-O-methyl-6-deoxyhexose, glucose, xylose, alanine, galactosamine and phosphorus in a molar ratio of 67:6.9:4.3:2.1:1.1:1.0:4.1. Data from analysis involving Smith degradation, methylation, 1H-NMR spectroscopy and optical rotation measurement showed that the polysaccharide was built up of three moieties, a rhamnan chain composed of about 70 D-rhamnose residues, the core chain and an oligosaccharide chain comprising 3-O-methyl-6-deoxyhexose, xylose, rhamnose and probably glucose. The repeating unit of the rhamnan chain was indicated to have the following structure:----3)D-Rha(alpha 1----3)D-Rha(alpha 1----2)D-Rha(alpha 1----. This structure is identical with that proposed previously for the repeating unit of the side chain of lipopolysaccharide from plant pathogenic bacteria Pseudomonas syringae pv. morsprunorum C28 [Smith, A.R.W., Zamze, S.E., Munro, S.M., Carter, K. J. and Hignett, R.C. (1985) Eur. J. Biochem. 149, 73-78].

Chromatography, Gel↗
PubMed1987

An enzyme catalyzing the liberation of N-acetylglucosamine from N-acetylglucosaminyl pyrophosphorylpolyprenol in Bacillus polymyxa membranes.

A novel enzyme which specifically hydrolyzes N-acetylglucosaminyl pyrophosphorylpolyprenol to liberate N-acetylglucosamine was found in membranes of Bacillus polymyxa AHU 1385. The enzyme seems to be inactive toward alpha-N-acetylglucosaminyl phosphorylundecaprenol, beta-N-acetylglucosaminyl phosphorylundecaprenol, N-acetylglucosamine 1-phosphate, N-acetylglucosamine 1-pyrophosphate, or UDP-N-acetylglucosamine. Much lower activities of the same enzyme were also found in membranes of several other strains of Bacilli.

Acetylglucosamine↗
PubMed1987

Type 1a glycogen storage disease with hepatoblastoma in siblings.

Clinical and histologic details of the two siblings with type 1a glycogen storage disease (GSD-1a) who developed hepatoblastoma are presented. The light microscopic studies on hepatic tumor in both siblings revealed fetal type of hepatoblastoma. Ultrastructural findings in Patient 2 showed markedly altered mitochondria, which were frequently surrounded by the rough endoplasmic reticulum. This is the first known occurrence with this association, and the third report on the familial occurrence of this neoplasm. Glycogen storage disease may increase the risk of hepatocellular carcinoma and hepatoblastoma.

Adult↗
PubMed1987

Biosynthesis of poly(galactosylglycerol phosphate) in Bacillus coagulans.

The pathway for the de novo synthesis of a teichoic acid, poly(galactosylglycerol phosphate), in Bacillus coagulans AHU 1366 was studied by means of characterization and stepwise conversion of lipid-linked intermediates. Incubation of membranes with UDP-N-acetylglucosamine and UDP-glucose yielded a disaccharide-linked polyprenylpyrophosphate, whose sugar moiety was characterized as glucosyl(beta 1----4)N-acetylglucosamine (Glc-GlcNAc). By incubation with membranes and CDP-glycerol, Glc-GlcNAc-PP-prenol was converted to a series of glycolipids characterized as (Gro-P)1-6-Glc-GlcNAc-PP-prenol (Gro = glycerol). Glc-[14C]GlcNAc-PP-prenol was converted to polymer by incubation with membranes, CDP-glycerol and UDP-galactose. Smith degradation of the polymer gave two radioactive fragments corresponding to (Gro-P)3-Glc-GlcNAc and (Gro-P)4-Glc-GlcNAc. These results, together with data on gel chromatography of radioactive polymer synthesized from UDP-[3H]galactose, CDP-glycerol and Glc-[14C]GlcNAc-PP-prenol, led to the conclusion that in this strain poly(galactosylglycerol phosphate) is probably synthesized through the following pathway: GlcNAc-PP-prenol----Glc-GlcNAc-PP-prenol----(Gro-P)3-4 -Glc-GlcNAc-PP-prenol----(Gro-P-Gal)n- (Gro-P)3-4-Glc-GlcNAc-PP-prenol----(Gro-P-Gal)n- (Gro-P)3-4-Glc-GlcNAc-P-peptidoglycan complex.

Bacillus↗
PubMed1987

Yolk sac tumors of the ovary and the human yolk sac.

In the present study a comparison was made between human yolk sacs and yolk sac tumors. Tubules surrounded by several to as many as 10 endodermal cells and intracellular tubules in one endodermal cell were frequently observed. The tubules were seen abundantly in the yolk sac of a 4-week pregnancy, and they resembled the reticular pattern of the yolk sac tumor. It was also observed that the papillary endoderm, which contained blood cells in the center and protruded into the endodermal tubules, resembled the Schiller-Duval body of yolk sac tumor. Ultrastructurally the tumor cells were similar to the yolk sac endoderm. alpha-Fetoprotein was positive in the yolk sac endoderm until approximately the seventh week of pregnancy. Yolk sac tumor was also alpha-fetoprotein-positive. In other words, our study of human yolk sacs of 4- to 11-week pregnancies presumes that the yolk sac tumor resembles the endoderm of 4- to 7-week pregnancies.

Endoderm↗
PubMed1987

Use of electroporation for high-molecular-weight DNA-mediated gene transfer.

Electroporation was used to introduce high-molecular-weight DNA into murine hematopoietic cells and NIH3T3 cells. CCRF-CEM cells were stably transfected with SV2NEO plasmid and the genomic DNA from G-418-resistant clones (greater than 65 kb) was introduced into mouse bone marrow and NIH3T3 cells by electroporation. NEO sequences and expression were detected in the hematopoietic tissues of lethally irradiated mice, with 24% of individual spleen colonies expressing NEO. The frequency of genomic DNA transfer into NIH3T3 cells was 0.25 X 10(-3). Electroporation thus offers a powerful mode of gene transfer not only of cloned genes but also of high-molecular-weight DNA into cells.

Animals↗