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G Larson

Publications and source records attributed to G Larson.

At least 91 records · Page 5Linked to original sources

Globoseries glycosphingolipids of human meconium.

Globoside and an extended globoseries glycosphingolipid with a blood group H determinant were isolated from pooled human meconia and structurally characterized by mass spectrometry, proton NMR spectroscopy, and degradational techniques using GC and GC-MS analyses. Both species contained mainly phytosphingosine and hydroxy fatty acids characteristic for human intestinal epithelial cells. With the same techniques also minor amounts of globoside with sphingosine and nonhydroxy fatty acids and a novel globoseries tetraglycosyl ceramide with a terminal N-acetylglucosamine were isolated and structurally characterized.

Acetylation↗

GalNAc beta 1----3 terminated glycosphingolipids of human erythrocytes.

Nonacid glycosphingolipids with 4 to 10 sugar residues isolated from pooled erythrocytes of blood group O donors have been efficiently separated as peracetylated derivatives on silicic acid. This procedure enabled a quantitative estimate of individual compounds and also revealed several GalNAc beta 1----3 terminated structures. The structural characterization of these glycolipids with 1H-NMR spectroscopy, direct inlet mass spectrometry, gas chromatography, and gas chromatography-mass spectrometry identified the compounds as GalNAc beta 1----3Gal alpha 1----4Gal beta 1----4Glc beta 1----1-N-acetyl sphingosine and GalNAc beta 1----3Gal alpha 1----4Gal beta 1----4Glc beta 1----1-N-acetyl phytosphingosine, GalNAc beta 1----3GalNAc beta 1----3Gal alpha 1----4Gal beta 1----4Glc beta 1----1 ceramide, and GalNAc beta 1----3Gal beta 1----4GlcNAc beta 1----3Gal beta 1----4Glc beta 1----1 ceramide.

Acetylation↗

Generalization of the effects of unilateral and bilateral ECT.

The correlation coefficients among four different measures of seizure duration (motor activity, EEG spikes, EEG total, tachycardia) were substantially lower with unilateral than bilateral ECT. This suggests that unilateral ECT is less well generalized through the brain than bilateral ECT.

Brain↗

Upper gastrointestinal bleeding: predictors of outcome.

We reviewed the records of 115 patients treated for upper gastrointestinal (UGI) bleeding on a general surgical and trauma service from January 1981 to June 1984. Clinical variables were analyzed with regard to three outcome criteria: mortality rate, blood transfusion requirements, and need for operation. Endoscopy was performed in all patients, usually within 24 hours of detection of bleeding. Thirty-six patients required greater than or equal to 5 U of blood, 27 patients required an operation for bleeding, and 26 patients (23%) died in the hospital. In 19 patients, death was attributed to the patient's underlying disease; in seven patients, death was due to bleeding or operation. Significant predictors of death were: age greater than or equal to 60 years old (p less than or equal to 0.02), disease in three organ systems (p less than 0.05), 5 U transfusion requirement (p less than 0.001), operation for bleeding necessary (p less than 0.03), lung/liver disease (p less than 0.03), and recent stress of major operation, trauma, or sepsis. Mortality rates were highest for bleeding varices (36%) and lowest for duodenal ulcers (7.7%) and gastric ulcers (15.8%). Endoscopy accurately determined the cause of UGI bleeding in most patients. The data suggest that the unchanging mortality rate for UGI bleeding is largely due to underlying disease or injury for which the success of current treatment is limited.

Adult↗

Specificity of binding of a strain of uropathogenic Escherichia coli to Gal alpha 1----4Gal-containing glycosphingolipids.

A strain of Escherichia coli originally isolated from urine of a patient with acute pyelonephritis was studied in detail for binding to glycosphingolipids. Bacteria labeled metabolically with [14C]glucose were layered over a glycolipid chromatogram and bound bacteria were detected by autoradiography. The detection was down to a few ng of glycolipid (pmol level) under these assay conditions. At a test level of 500 ng all glycolipids (more than a dozen molecular species analyzed) with Gal alpha 1----4Gal as an internal or terminal part bound the bacteria strongly while glycolipids known to lack this sequence were negative. Conformational analysis using hard sphere calculations including the exo-anomeric effect showed a bend in the saccharide chain at this disaccharide with a largely hydrophobic surface of the convex side, probably being part of the binding epitope. Mixtures of glycolipids isolated from a human ureter scraping and from urinary sediments bound bacteria in the 2- to 7-sugar interval. Thus, this infectious strain of E. coli recognizes glycolipids being present in epithelial cells lining the urinary tract.

ABO Blood-Group System↗

Carbohydrate-specific adhesion of bacteria to thin-layer chromatograms: a rationalized approach to the study of host cell glycolipid receptors.

Conditions have been adapted for the binding of intact bacteria to glycosphingolipids in a thin-layer chromatogram. Bacteria labeled externally with 125I or metabolically with other isotopes are layered on the plate and after repeated washing the bound bacteria are detected by autoradiography. Using this technique several kinds of bacteria have been shown to adhere to the plate in a carbohydrate-specific way with practically no background binding. Among the advantages of the method is the possible detection of a minor receptor component of a complex mixture extracted from a target cell, facilitating the isolation of the receptor for structural studies. In addition, the multivalent solid-phase presentation of the receptor candidate should also reveal low-affinity binding sites, which may escape detection in traditional inhibition experiments with soluble oligosaccharides.

Adhesiveness↗

Lewis blood group antigens defined by monoclonal anti-colon carcinoma antibodies.

Monoclonal antibodies directed against human cancer cells were prepared by the murine hybridoma technique. These antibodies detect Lewis blood group antigens as determined by indirect solid-phase radioimmunoassay, hapten inhibition studies, and chromatogram binding assay. One monoclonal antibody is specific for the Lea terminal carbohydrate of Gal beta 1----3Glc NAc(4----1 alpha Fuc) beta 1----3LacCer. Five monoclonal antibodies react with the Leb terminal carbohydrate sequence of Fuc alpha 1----2Gal beta 1----3GlcNAc(4----1 alpha Fuc) beta 1----3LacCer, and four of these antibodies are highly specific for this glycolipid and do not react with other similar di- and monofucosylated glycolipids. One of the anti-Leb antibodies cross-reacts with blood group H glycolipid and has binding properties similar to those of the previously described antibody NS-10-17 [M. Brockhaus, J. L. Magnani, M. Blaszczyk, Z. Steplewski, H. Koprowski, K.-A. Karlsson, G. Larson, and V. Ginsburg (1981) J. Biol. Chem. 256, 13223-13225]. Two antibodies react with both the Lea and Leb antigens, though both bind preferentially to Leb.

Antibodies, Monoclonal↗

A novel approach to the study of glycolipid receptors for viruses. Binding of Sendai virus to thin-layer chromatograms.

A method for the binding of virus to a silica gel thin-layer chromatogram is presented. After development the chromatogram is overlayed with the 125I-labelled virus and the bound virus is autoradiographed. Alternatively, the unlabelled virus may be detected after exposure to monoclonal antibody and labelled anti-antibody. The Sendai virus strain used did not bind to brain gangliosides earlier proposed to be receptors, but bound to human erythrocyte gangliosides. This finding may be explained by the existence of Sendai virus variants with different receptor specificities.

Animals↗

Identification of Leb antigens in meconium of a phenotypically a Le(a+ b-) non-secretor individual.

Blood group active fucolipids of human meconium have been shown to correlate to the ABH and Lewis blood groups and to the secretor status of the corresponding children. Using a monoclonal anti-Leb antibody and an antibody to chromatogram binding assay the presence of Leb antigens in meconium of a phenotypically A Le(a+ b-) non-secretor individual is here demonstrated. Phenotype was determined on cord blood and saliva obtained 2 years after birth.

Antibodies, Monoclonal↗

Characterization of monoclonal antibodies specific for the Lewis a human blood group determinant.

Four hybridoma cell lines were derived from the spleen cells of mice immunized with the neutral glycolipids of human meconium. The antibodies secreted by these lines were specific for the Lewis a antigen of the human Lewis blood group system as determined by solid phase immunoassay using synthetic carbohydrate antigens and by plate binding assay and thin layer chromatography-autoradiography using natural glycolipid antigens. Coating protein A-bearing Staphylococcus aureus with one of the antibodies yielded a stable reagent that produced rapid agglutination of Lewis a positive human erythrocytes. The fine structural specificity of these antibodies was assessed by competition radioimmunoassay using synthetic structural analogs of Lewis a conjugated to bovine serum albumin. One antibody was specific for the Lewis a trisaccharide (Gal beta 1 leads to 3(Fuc alpha 1 leads to 4) beta GlcNAc), while a second recognized the entire Lea (1 leads to 3) beta Gal tetrasaccharide. The third and fourth were directed at topography largely provided by only the alpha Fuc and beta GlcNAc units. These monoclonal antibodies not only represent potentially useful reagents for detecting the Lewis a antigen but also provide a system for studying precise relationships between anticarbohydrate antibody structure and binding specificity.

Animals↗

Mouse monoclonal antibodies against human cancer cell lines with specificities for blood group and related antigens. Characterization by antibody binding to glycosphingolipids in a chromatogram binding assay.

Solid phase radioimmunoassay and a chromatogram binding assay were used to characterize the binding specificities of five monoclonal antibodies generated from mice immunized with human tumor cell lines when tested against various glycolipids. Four antibodies derived from mice immunized with pancreatic carcinoma cells detected specifically the human blood group B determinant, Gal alpha 1 leads to 3Gal (2 comes from 1 alpha Fuc). These antibodies preferred type 2 (Gal beta 1 leads to 4GlcNAc) glycolipids. No reactivity was detected with a rat B determinant based on GalNAc. An antibody derived following immunization with a rectal carcinoma cell line was shown to have binding properties identical with those of an antibody that reacts specifically with the stage-specific embryonic mouse antigen (SSEA-1), bearing the determinant Gal beta 1 leads to 4GlcNAc (3 comes from 1 alpha Fuc) (Gooi, H. C., Feizi, T., Kapadia, A., Knowles, B. B., Solter, D., and Evans, M. J. (1981) Nature 292, 156-158). Thin layer chromatography was used to detect the binding of a monoclonal anti-tumor antibody recently shown to react with a sialylated Lea glycolipid (Magnani, J. L., Nilsson, B., Brockhaus, M., Zopf, D., Steplewski, Z., Koprowski, H., and Ginsburg, V. (1982) Fed. Proc 41, 898) and an anti-Leb antibody (Brockhaus, M., Magnani, J. L., Blaszczyk, M., Steplewski, Z., Koprowski, H., Karlsson, K.-A., Larson, G., and Ginsburg, V. (1981) J. Biol. Chem. 256, 13223-13225) to mixtures of glycolipids from normal and tumor tissues.

Adenocarcinoma↗

Mass spectrometry of a human tumor glycolipid antigen being defined by mouse monoclonal antibody NS-19-9.

With an antibody-to-chromatogram binding assay to follow the preparation a glycolipid was isolated from human pancreatic carcinoma using a mouse monoclonal antibody of apparent specificity for gastrointestinal tumors. Direct probe mass spectrometry of three derivatives established the sugar sequence as NeuAc-hexose-(fucose)N-acetylhexosamine-hexose-hexose and the ceramide to be composed mainly of phytosphingosine and 16-24 carbon 2-hydroxy fatty acids. NMR spectroscopy of two of the derivatives made likely the presence of the sequence Gal beta 1 leads to 3GlcNAc(4 comes from 1 alpha Fuc)beta 1 leads to, which is the blood group Lewis a determinant. This is in agreement with recent results from degradation studies.

Adenocarcinoma↗

Chemical characterization of a blood group H type pentaglycosylceramide of human small intestine.

A blood group H type pentaglycosylceramide was isolated in relatively large amounts from human adult small intestine (52 mg from one individual) and human meconium (fetal origin). The structure was made likely by mass spectrometry and NMR spectroscopy of non-degraded permethylated and permethylated-LiAlH4-reduced glycolipid and by degradation to be Fuc alpha 1 leads to 2Gal beta 1 leads to 3GlcNAc beta 1 leads to 3Gal beta 1 leads to 4Glc beta 1 leads to 1Cer. The ceramide was composed mainly of phytosphingosine and 2-hydroxy 16-24 carbon fatty acids. This novel type 1 chain species (Gal beta 1 leads to 3GlcNAc) was not accompanied by the type 2 chain isomer (Gal beta 1 leads to 4GlcNAc) which in contrast is the sole species in human erythrocyte and dog small intestine.

ABO Blood-Group System↗