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J Dabrowski

Publications and source records attributed to J Dabrowski.

At least 19 recordsLinked to original sources
PubMed1992

Solution conformations of GM3 gangliosides containing different sialic acid residues as revealed by NOE-based distance mapping, molecular mechanics, and molecular dynamics calculations.

The conformation of the GM3 ganglioside, Neu5Ac alpha 2-3Gal beta 1-4Glc beta 1-1 Cer, and its analogs containing the Neu5Gc or Neu4Ac5Gc residues (Gc = glycolyl, CH2OHCO) was investigated in Me2SO-d6 solution with the aid of a distance-mapping procedure based on rotating-frame NOE contacts, with hydroxyl protons being used as long-range sensors defining the distance constraints. A pronounced flexibility found for both the Neu-Gal and Gal-Glc linkages was confirmed by 1000-ps molecular dynamics simulations. Similar results, although based on a smaller number of NOE constraints, were obtained for GM3 gangliosides anchored in mixed D2O/dodecylphosphocholine-d38 micelles and for the Neu5Ac-, Neu5Gc-, and Neu5,9Ac2-sialyllactoses dissolved in D2O. No noteworthy differences in conformational behavior of the glycan chains of the three gangliosides or sialyllactoses were observed in either of the media.

Animals↗
PubMed1992

The structure of the O-specific polysaccharide chain of the lipopolysaccharide of Salmonella arizonae O61.

The O-specific polysaccharide was obtained by mild degradation of the Salmonella arizonae O61 lipopolysaccharide with acid. It contained 2-acetamido-2-deoxy-D-glucose, 2-acetamidino-2,6-dideoxy-L-galactose (FucAm), and 7-acetamido-3,5,7,9-tetradeoxy-5-[(R)-3-hydroxybutyramido]-D- glycero-L-galacto-nonulosonic acid (Sug). On the basis of partial acid hydrolysis with 0.1 M HCl, solvolysis with anhydrous HF in methanol, and 1H- and 13C-NMR analysis (including 1H/13C inversely correlated spectroscopy for localisation of N-acyl substituents), it was concluded that the O-specific polysaccharide had the following structure. ----3)-alpha-L-FucAm-(1----3)-alpha-D-GlcNAc-(1----8)-beta-Sug+ ++-(2---- The O-antigen of S. arizonae O61 is structurally related to that of Pseudomonas aeruginosa O12, thus explaining the known serological cross-reactivity between these micro-organisms.

Carbohydrate Conformation↗
PubMed1992

Carbohydrate structure of a thrombin-like serine protease from Agkistrodon rhodostoma. Structure elucidation of oligosaccharides by methylation analysis, liquid secondary-ion mass spectrometry and proton magnetic resonance.

The carbohydrate side chains of the thrombin-like serine protease ancrod from the venom of the Malayan pit viper Agkistrodon rhodostoma were liberated from tryptic glycopeptides by treatment with peptide-N4-(N-acetyl-beta-glucosaminyl)asparagine amidase F and fractionated by high-performance liquid chromatography. Glycans obtained were characterized by digestion with exoglycosidases, methylation analysis and, in part, by liquid secondary-ion mass spectrometry and 1H-NMR spectroscopy. The results reveal that this snake venom glycoprotein contains partially truncated di-, tri- and tetraantennary complex type N-glycans carrying Fuc(alpha 1-6) residues at the innermost N-acetylglucosamine and solely (alpha 2-3)-linked sialic acid substituents. As a characteristic feature, ancrod oligosaccharides comprise mainly sialylated Gal beta 3GlcNAc beta lactosamine antennae. Furthermore, a small proportion of the sugar chains were found to carry a NeuAc alpha 3GalNAc beta 4GlcNAc beta antenna exclusively linked to C-2 of Man(alpha 1-3) residues of the pentasaccharide core. Thus, many of the glycans found represent novel glycoprotein-N-glycan structures.

Carbohydrate Sequence↗
PubMed1992

The changes in bile flow and its composition in sheep following liver damage by carbon tetrachloride.

Sheep were prepared surgically in a manner permitting the measurement of bile flow by preserving its enterohepatic circulation. Carbon tetrachloride (CCl4) was administered intraruminally in a dose 0.5 ml/kg b.w. After CCl4 administration a decrease in bile flow and bile acid excretion was observed. The decrease in bile flow observed after CCl4 administration was lower than the decrease in bile acid output. Thus it can be suggested that in this condition the effects of bile acid output on the bile secretion can be partially abolished and maintaining of relatively high bile flow is connected with an increase in the bile acid-independent bile flow. The increase of the bilirubin concentration in bile was observed after acute liver damage by carbon tetrachloride.

Animals↗
PubMed1992

Prevalence of HIV-antibodies in maritime workers and in other selected population groups in Poland.

The objective of the present work was to determine prevalence of HIV-antibodies in the following population groups: 1. Seamen, fishermen and dockers from region of Gdańsk and Szczecin 2. Travellers abroad. 3. Special risk groups (intravenous drug users, prostitutes, homosexuals, haemophiliacs) mostly from Gdańsk region. 4. Hospital patients, prisoners, other people. Abbott recombinant HIV 1/HIV 2 EIA was used for the detection of antibodies to HIV type 1 and/or type 2. In the period from 1987 to 1992, 70,297 examinations were made. HIV-antibodies were detected in 165 people (0.23%). Out of 35,084 subjects in the first group (926 women and 34,158 men). 20 men were found seropositive (0.06%). The majority of them--16 men were seamen, 3 were fishermen and one was a harbour worker. In the second group made of 27,403 people including 3,640 females, HIV-antibodies were revealed in 9 men (0.04%) and one woman. In the third group, there were 965 people including 482 women; among them there were 104 men and 19 women infected (12.8%). Out of the 349 prostitutes examined 2 were infected (0.05%). Among 79 homosexuals, 4 were found infected. In the sample of 14 haemophiliacs none demonstrated HIV-antibodies. In 6,845 subjects of the fourth group (5938 males and 907 females), 12 males were seropositive (0.18%). In that number 5 were prisoners, other 5 were hospital patients and 2 were known to have homosexual relationship with infected men. The majority of subjects with HIV-antibodies were men--145 (88%) of the total number of subjects infected, aged 20-40.

Adult↗
PubMed1992

[Diagnostic value of planar perfusion scintigraphy of the heart using Technetium Tc 99m with methoxy-isobutylisonitrile (MIBI)].

99mTc-MIBI (2 methoxy -isobutylisonitrile) belongs to the new generation of radiopharmaceuticals used for studies of myocardial perfusion. Particularly convenient characteristics of the compound prompted numerous studies of its usefulness for scintigraphic diagnostics of coronary artery disease and myocardial heart infarct (detection, localization, size). In the present paper the diagnostic utility of planar heart scintigraphy with 99mTc MIBI is assessed, the compound had been prepared in the Department of Nuclear Medicine, Medical University of Lódź. The scope of the study included detection of stress induced ischaemia and of permanent perfusion defects, treated as post infarct scars in myocardium. The study was made on 109 patients (78 males, 31 females; age 32-68 years). The first group comprised 56 patients with suspected or diagnosed coronary artery disease, however, without history of previous heart infarct. Results of stress and rest scintigraphy were juxtaposed with those of coronarography, which served as a reference method. In 25 patients the latter revealed critical (greater than 70%) stricture of 1 or 2 coronary arteries. In 31 patients of this group the vessels were either of normal appearance or only marginally stricture. Sensitivity, specificity and accuracy of the scintigraphy in diagnosis of ischaemia due to critical narrowing of coronary arteries amounted to 80, 84 and 82 per cent, respectively. Localisation of perfusion defects was adequate in 20 out of 31 vessels (64 per cent). The second group of patients included 53 individuals with previous heart infarct (25 and 11 had a transmural and nontransmural infarct of the anterior wall, respectively; in 12 and 5 a transmural and nontransmural infarct of the inferior wall was diagnosed, accordingly).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

O-specific polysaccharide of Hafnia alvei lipopolysaccharide isolated from strain 1211. Structural study using chemical methods, gas-liquid chromatography/mass spectrometry and NMR spectroscopy.

The Hafnia alvei strain 1211 O-specific polysaccharide is composed of 3-amino-N-(D-3'-hydroxybutyryl)-3,6-dideoxy-D-galactose, N-acetyl-D-galactosamine, N-acetyl-D-glucosamine and D-glucose (1:1:2:2). On the basis of sugar and methylation analyses, Smith degradation, and one- and two-dimensional 1H- and 13C-NMR spectroscopy, the polysaccharide was shown to be an O-acetylated polymer of the repeating hexasaccharide unit, ----2D(4-OAc)Fucp3NAcyl beta 1----6DGlcpNAc alpha 1---- (DGlcp beta 1----3)4DGalpNAc alpha 1----3DGlcpNAc beta 1----2DGlcp beta 1----, where DFucp3NAcyl = 3-amino-N-(D-3'-hydroxybutyryl)-3,6-dideoxy-D- galactopyranose. The O-specific polysaccharide showed some microheterogeneity due to incomplete substitution by terminal glucose.

Acetylgalactosamine↗
PubMed1991

Structure of the O-specific, sialic acid containing polysaccharide chain and its linkage to the core region in lipopolysaccharide from Hafnia alvei strain 2 as elucidated by chemical methods, gas-liquid chromatography/mass spectrometry, and 1H NMR spectroscopy.

Mild acid hydrolysis of Hafnia alvei strain 2 lipopolysaccharide released no O-specific polysaccharide but instead gave a monomeric octasaccharide repeating unit with N-acetylneuraminic acid as the reducing terminus. In addition, a dimer of the octasaccharide repeating unit, and also a decasaccharide composed of a fragment of the O-specific polysaccharide chain and the core region, were obtained in minute amounts. On the basis of the sugar and methylation analyses, periodate oxidation, and 1H NMR spectroscopy of the lipopolysaccharide hydrolytic products, the biological repeating unit of the O-specific polysaccharide was shown to be a branched octasaccharide: (Formula; see text) The linkage between the O-specific polysaccharide chain and core region has also been determined and has yield strong evidence that N-acetylneuraminic acid is an inherent lipopolysaccharide component. The lipopolysaccharide of H. alvei strain 2 is the first lipopolysaccharide reported to contain 4-substituted neuraminic acid in its O-specific polysaccharide region.

Carbohydrate Conformation↗
PubMed1991

Core region of Citrobacter O23 lipopolysaccharide. Structure elucidation by chemical methods, gas chromatography/mass spectrometry and NMR spectroscopy at 500 MHz.

A novel enterobacterial core region in Citrobacter O23 lipopolysaccharide is described. Its structure was determined by methylation analysis/mass spectrometry, chemical degradation and one- and two-dimensional 1H-NMR spectroscopy: [formula; see text] where PPEtN stands for diphosphorylethanolamine, and dOclA for 3-deoxy-D-manno-octulosonic acid.

Citrobacter↗
PubMed1991

Solution conformation of Forssman antigen probed by NOE and exchange interactions.

The conformation of Forssman glycolipid, GalNAc alpha 1-3GalNAc beta 1-3Gal alpha 1-4Gal beta 1-4Glc beta 1-1ceramide, was analysed with the aid of the rotating frame NOE and Hartmann-Hahn spectroscopy. NOE contacts between C-, O-, and N-linked protons were used for distance mapping. The glycosidic bonds that are common to globotriaosylceramide and globoside showed a similar flexibility as found for these compounds [Poppe et al., (1990) Eur. J. Biochem. 189, 313-325; J. Am. Chem. Soc. 112, 7762-7771]. In contrast, the conformational mobility of the terminal GalNAc alpha 1-3GalNAc beta linkage appears to be restrained. A new approach, based on 2D exchange spectroscopy, was proposed for revealing of spatial proximities between exchangeable protons in Me2SO solution.

Carbohydrate Conformation↗
PubMed1990

Novel phosphorus-containing glycosphingolipids from the blowfly Calliphora vicina Meigen. Structural analysis by 1H and 1H[31P]-edited NMR spectroscopy at 600 and 500 megahertz.

Two novel phosphorus-containing neutral glycosphingolipids of the arthro series were isolated from the blowfly Calliphora vicina Meigen: GalNAc alpha 1----4GalNAc beta 1----(X---- 6)4GlcNAc beta 1----3Man beta 1----4Glc beta 1----1-ceramide and GalNAc beta 1----(X----6)4GlcNAc beta 1----3Man beta 1----4Glc beta 1----1- ceramide (X = -O-P(O)(O-)-OC-H2CH2NH3+). The primary structure of the ceramide pentasaccharide was elucidated de novo using two-dimensional 1H NMR correlation spectroscopy at 500 MHz and multistep relayed coherence transfer spectroscopy at 600 MHz. Localization of the 2'-aminoethyl phosphate substituent was established with the aid of 1H-detected, 31P-edited NMR spectroscopy at 500/202 MHz.

Animals↗
PubMed1990

Three-dimensional structure of the oligosaccharide terminus of globotriaosylceramide and isoglobotriaosylceramide in solution. A rotating-frame NOE study using hydroxyl groups as long-range sensors in conformational analysis by 1H-NMR spectroscopy.

Spatial structures of the oligosaccharide parts of globotriaosylceramide, Gal(alpha 1-4)Gal(beta 1-4)Glc(beta 1-1)Cer (Cer = ceramide) and isoglobotriaosylceramide, Gal(alpha 1-3)Gal(beta 1-4)Glc(beta 1-1)Cer were investigated in (C2H3)2SO solution by means of laboratory and rotating frame NOE, hydroxyl protons being used as long-range sensors defining the distance constraints. Both oligosaccharides were found to exist in more than one conformation interconverting rapidly on the NMR time scale. The conformation of the Gal(alpha 1-4)Gal(beta 1-4)Glc beta trisaccharide dissolved in 2H2O appeared to be the same as that of the corresponding part of the glycosphingolipid in (C2H3)2SO solution.

Carbohydrate Conformation↗
PubMed1990

Oligosaccharides at individual glycosylation sites in glycoprotein 71 of Friend murine leukemia virus.

Glycoprotein 71 from Friend murine leukemia virus was digested with proteases and the glycopeptides obtained were isolated and assigned, by amino acid sequencing, to the eight N-glycosylated asparagines in the molecule; only Asn334 and Asn341 could not be separated. The oligosaccharides liberated from each glycopeptide by endo-beta-N-acetylglucosaminidase H, or by peptide-N4-(N-acetyl-beta-glucosaminyl)asparagine amidase F, were fractionated and subjected to structural analysis by one- and two-dimensional 1H NMR, as well as by methylation/gas-liquid-chromatography/mass-fragmentography. At each glycosylation site, the substituents were found to be heterogeneous including, at Asn334/341 and Asn410, substitution by different classes of N-glycans: oligomannosidic oligosaccharides, mainly Man alpha 1----6(Man alpha 1----3)Man alpha 1----6(Man alpha 1----3)Man beta 1----4GlcNAc beta 1----4GlcNAc beta 1----, were detected at Asn168, Asn334/341 and Asn410. Hybrid species, partially sialylated, intersected and (proximally) funcosylated Man alpha 1----6(Man alpha 1----3)Man alpha 1----6 and Man alpha 1----3Man alpha 1----6 and Man alpha 1----3Man alpha 1----6(Gal beta 1----4GlcNAc beta 1----2Man alpha 1----3)Man beta 1----4GlcNAc beta 1----4GlcNAc beta 1----, were found at Asn12, as previously published [Schlüter, M., Linder, D., Geyer, R., Hunsmann, H., Schneider, J. & Stirm, S. (1984) FEBS Lett. 169, 194-198] and at Asn334/341. N-Acetyllactosaminic glycans, mainly partially intersected and fucosylated NeuAc alpha 2----3 or Gal alpha 1----3Gal beta 1----4GlcNAc beta 1----2Man alpha 1----6(NeuAc alpha 2----6 or NeuAc alpha 2----3Gal-beta 1----4GlcNAc beta 1----2Man alpha 1----3)Man beta 1----4GlcNac beta 1----4GlcNAc beta 1---- with some bifurcation at ----6Man alpha 1----6, were obtained from Asn266, Asn302, Asn334/341, Asn374 and Asn410. In addition, Thr268, Thr277, Thr279, Thr304/309, as well as Ser273 and Ser275, were found to be O-glycosidically substituted by Gal beta 1----3GalNAc alpha 1----, monosialylated or desialylated at position 3 of Gal or/and position 6 of GalNAc.

Amino Acid Sequence↗
PubMed1990

The determination of phytosphingosine-containing globotriaosylceramide from human kidney in the presence of lactosylceramide.

Globotriaosylceramide, the natural substrate of alpha-galactosidase A (the enzyme deficient in Fabry's disease) was prepared from human kidney by repeated medium pressure chromatography on Lichroprep Si 60 (E. Merck) before and after peracetylation. The apparently homogeneous preparation migrating as a single band on HPTLC was analysed by fast atom bombardment mass spectrometry and 1H-NMR at 500 MHz. It was found that in this fraction two major molecular species were comigrating: Gal alpha 1-4Gal beta 1-4Glc beta 1-1ceramide with nervonic and lignoceric acid linked to phytosphingosine and Gal beta 1-4Glc beta 1-1 ceramide with palmitic acid linked to sphingosine.

Antigens, CD↗
PubMed1990

Structural studies on Hafnia alvei 114-60 O-antigen.

The structure of Hafnia alvei 114-60 O-antigen has been established using sugar and methylation analyses as well as 1H-NMR spectroscopy. The results obtained proved that the repeating unit of Hafnia alvei 114-60 O-antigen is identical to that of Hafnia alvei ATCC 13337 standard strain and has the following structure: [formula: see text]

Antigens, Bacterial↗
PubMed1989

O-specific polysaccharides of Hafnia alvei lipopolysaccharides isolated from two serologically related strains: ATCC 13337 and 1187. A serological and structural study using chemical methods, gas chromatography/mass spectrometry and NMR spectroscopy at 500 MHz.

The O-specific polysaccharides of Hafnia alvei ATCC 13337 standard strain and 1187 strain have been isolated and characterized. By means of 1H-NMR spectroscopy, methylation analysis and periodate oxidation, the repeating unit of the polysaccharides could be allocated the respective structures. (formula; see text) where Acyl = D-3-hydroxybutyryl, and 3-O-acetylation was to about 66%. The structural similarity of the polysaccharides was confirmed in the serological study; their epitopes were determined and the importance of various structural elements for the serological specificity was discussed.

Carbohydrate Conformation↗