Preferencje help
Polish version English version Język
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 16

Liczba wyników na stronie
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych:  glycosphingolipid
help Sortuj według:

help Ogranicz wyniki do:
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
1

Photochemical labeling of HL-60 cell membrane proteins with radioiodinated, 4-azidosalicylic acid acylated derivatives of gangliosides

100%
Pacuszka T., Panasiewicz M., Hoser G., Kawalec M.
Acta Biochimica Polonica
|
1998
|
tom 45
|
nr 2
To detect HL-60 human promyelocytic leukemia cell proteins involved in the uptake of gangliosides from the culture medium we used photoreactive, 4-azidosalicylic acid (ASA) acylated and radioiodinated (200 Ci/mmole) derivatives of GM3, GD3, GM1, and FucGM1 gangliosides. Gangliosides-ASA, added to the medium at 15-20 nM concentration, followed a similar time course of uptake. After 1 min incubation cell bound gangliosides-ASA could not be removed with trypsin, but only 5-10% remained after incubation with BSA. The proportion of cell bound gangliosides-ASA resistant to BSA treatment increased with time of incubation up to 76% after 20 h. As shown on TLC, GM3- and GD3-ASA were catabolized to LacSph-ASA and ceramide-ASA, while GM1-ASA was hydrolyzed to GM2-ASA. FucGM1-ASA was converted to GM1-ASA very slowly. Upon irradiation with UV lamp, cell bound gangliosides-ASA crosslinked to and photolabeled many proteins but the distribution of radioactivity after SDS/PAGE was very uneven and did not correlate with Coomassie staining. In all experiments the 42 kDa protein bands were most intensely photolabeled. Photolabeling of 42 kDa proteins decreased with time of incubation as compared to lower molecular mass proteins. With all gangliosides-ASA used similar but not identical protein photolabeling patterns were obtained. Photolabeling patterns with GM3- and GD3-ASA differed from those with GM1- and FucGM1-ASA.
2

Recent controversy surrounding lipid rafts

100%
Skwarek M.
Archivum Immunologiae et Therapiae Experimentalis
|
2004
|
tom 52
|
nr 6
3

Matrix-assisted laser desorption ionization time-of-flight mass spectrometric analysis of glycosphingolipids including gangliosides

100%
Taketomi T., Hara A., Uemura K., Sugiyama E.
Acta Biochimica Polonica
|
1998
|
tom 45
|
nr 4
Long chain base compositions of gangliosides containing mainly stearic acid could be determined without any chemical modification by matrix-assisted laser desorption ionization time-of-flight mass spectrometry with delayed ion extraction (DE MALDI-TOF MS). The analytical results for the long chain base compositions of various samples of GM1 from the brain tissues of patients with different diseases at different ages confirmed that the proportion of d20:1 (icosasphingosine) and d20 (icosa-sphinganine) of the total sphingosine bases increased quickly until adolescent or adult age and then remained constant slightly exceeding 50%; this value was evidently higher than the proportion of d20:1 and d20 of GM1 in various adult mammalian brains. A long chain base composition of GM1 from the brain tissue of a patient with infantile type of GM1-gangliosidosis at 4y2m was abnormal and so was in two sibling patients with Spielmeyer-Vogt type of juvenile amaurotic idiocy at 19y and 21y in spite of that in the latter there was no accumulation of GM1 in the brain tissue. On the other hand, a patient with adult type of GM1 gangliosidosis at 66y showed a local accumulation of GM1 in the putamen and caudate nucleus, but its long chain base composition was found to be normal. It was of interest that the white matter of Eker rat with hereditary renal carcinoma contained a large amount of plasmalocerebroside as compared with the amount of cerebroside and sphingomyelin. The individual molecular species of plasmalocerebroside were identified by DE MALDI-TOF MS.
4

CD1: a singed cat of the three antigen presentation systems

84%
Kaczmarek R., Pasciak M., Szymczak-Kulus K., Czerwinski M.
Archivum Immunologiae et Therapiae Experimentalis
|
2017
|
tom 65
|
nr 3
5

GSL-enriched membrane microdomains in innate immune responses

84%
Nakayama H., Ogawa H., Takamori K., Iwabuchi K.
Archivum Immunologiae et Therapiae Experimentalis
|
2013
|
tom 61
|
nr 3
6

Distinct roles for sphingolipids and glycosphingolipids at different stages of neuronal development

84%
Futerman A. H.
Acta Biochimica Polonica
|
1998
|
tom 45
|
nr 2
Studies on the roles of sphingolipids (SLs) and glycosphingolipids (GSLs) at distinct stages of neuronal development have been performed using primary cultures of hippocampal neurons, which are unique among neuronal cultures inasmuch as they develop by a well-characterized and stereotypic sequence of events that gives rise to fully differentiated axons and dendrites. Our data demonstrate that SLs and GSLs play at least three distinct roles in regulating neuronal development, namely: (i) ceramide enhances the formation of minor neuronal processes from lamellipodia and the subsequent stage of axonogenesis; (ii) glucosylceramide synthesis, but not the synthesis of higher-order GSLs, is required for normal axon growth and for accelerated axonal growth upon stimulation by growth factors; and (iii) at both of these stages, ceramide at high concentrations can induce apoptotic cell death. Together, these observations are consistent with the possibility that minor process formation and apoptosis are regulated by ceramide-dependent signaling pathways, whereas axonal growth requires glucosylceramide synthesis, perhaps to support an intracellular transport pathway.
7

Epitope dissection of receptor-active gangliosides with affinity for Helicobacter pylori and influenza virus

84%
Miller-Podraza H., Larsson T., Nilsson J., Teneberg S., Matrosovich M., Johansson L.
Acta Biochimica Polonica
|
1998
|
tom 45
|
nr 2
Receptor-active gangliosides with affinity for Helicobacter pylori and influenza virus were chemically modified and analyzed by negative ion fast atom bombardment mass spectrometry (FAB MS) or electron ionization mass spectrometry (EI MS) after permethylation. Derivatizations included mild periodate oxidation of the sialic acid glycerol tail or conversion of the carboxyl group to primary alcohol or amides. The modified gangliosides were then tested for binding affinity using thin-layer plates overlaid with labeled microbes or microbe-derived proteins. Mild periodate oxidation, which shortens sialic acid tail without destruction of sugar cores, abolished or drastically reduced binding of H. pylori and avian influenza virus to sialyl-3-paragloboside (S-3-PG). The same effect was observed in the case of binding of the human influenza virus to receptor-active gangliosides of human leukocytes. Conversion of S-3-PG or leukocyte gangliosides to primary alcohols or amides also abolished the binding. However, mild periodate oxidation had no effect on binding of NAP (neutrophil-activating protein of H. pylori) to the active ganglioside.
8

Involvement of envelope-glycoprotein glycans in HIV-1 biology and infection

67%
Raska M., Novak J.
Archivum Immunologiae et Therapiae Experimentalis
|
2010
|
tom 58
|
nr 3
191-208
9

Impact of microbes on autoimmune diseases

67%
Danzer C., Mattner J.
Archivum Immunologiae et Therapiae Experimentalis
|
2013
|
tom 61
|
nr 3
10
Content available remote

Caveolae, caveolin and control of vascular tone: nitric oxide (NO) and endothelium derived hyperpolarizing factor (EDHF) regulation

67%
Rath G., Dessy C., Feron O.
Journal of Physiology and Pharmacology. Supplement
|
2009
|
tom 60
|
nr 4
11

In comparison to progenitor platelets, microparticles are deficient in GpIb, GpIb-derived carbohydrates, glycerophospholipids, glycosphingolipids, and ceramides

67%
Zdebska E., Wozniak J., Dzieciatkowska A., Koscielak J.
Acta Biochimica Polonica
|
1998
|
tom 45
|
nr 2
Activated blood platelets shed microparticles with procoagulant activity that probably participate in normal hemostasis. We have isolated spontaneously formed microparticles from human blood and analysed them for ultrastructure, antigenic profile, and biochemical composition. In transmission electron microscopy microparticles appeared as regular vesicles with a mean diameter of 300 nm (50-600 nm). In flow cytometry almost all microparticles reacted with fluorescein isothiocyanate (FITC) labeled antibody to platelet glycoprotein complex IIb-IIIa (GpIIb-IIIa) and with FITC-annexin V but only 40-50% of microparticles reacted with FITC-antibody to platelet glycoprotein Ib (GpIb). The latter result was confirmed by double labeling of microparticles with FITC-antibody to GpIIb-IIIa and phycoerythrin (PE) labeled antibody to GpIb. Large microparticles reacted better with anti-GpIb than the small ones. A decreased level of GpIb was also demonstrated by SDS/polyacrylamide gel electrophoresis of microparticles. Compositional studies indicated, that in terms of cholesterol and protein contents, microparticles resembled platelets rather than platelet membranes as previously thought. They are, however, deficient in certain components. Thus, in comparison to platelets, microparticles had reduced contents of sialic acid (by 56.4%), galactosamine (by 48.2%), glucosamine (by 22.4%), galactose by (11.8%) and fucose (by 21.6%). Mannose content was increased by 11.8%. Total phospholipids in microplatelets were lower by 17.8%. Glycerophospholipids only were affected with phosphatidylserine being decreased as much as by 43.2%. Neutral glycosphingolipids, gangliosides and ceramides in microparticles were reduced by half. We conclude that the biochemical composition of microparticles probably reflects previous activation of progenitor platelets
12

Processing of sphingolipid activator proteins and the topology of lysosomal digestion

67%
Sandhoff K., Kolter T.
Acta Biochimica Polonica
|
1998
|
tom 45
|
nr 2
Plasma membrane derived glycosphingolipids (GSLs) destined for digestion are internalized through the endocytic pathway and delivered to the lysosomes. There, GSLs are degraded by the action of exohydrolases, which are supported, in the case of GSLs with short oligosaccharide chains, by sphingolipid activator proteins (SAPs). Four of the SAPs, SAP-A to -D (also called saposins) are synthesized from a single precursor protein (pSAP). Intracellular routing of pSAP and of the GM2 activator protein is only in part dependent on mannose-6-phosphate residues. Their endocytosis occurs in a carbohydrate-independent manner. The inherited deficiencies of individual activators, the GM2 activator, SAP-B, and SAP-C, as well as the deficiency of the precursor pSAP give rise to different, neuronal, white matter or visceral sphingolipid storage diseases. The analysis of cultured fibroblasts from corresponding patients suggests a new model for the topology of endocytosis and lysosomal digestion. It supports the hypothesis that endocytosis of plasma membrane-derived lipids occurs via small intraendosomal and intralysosomal vesicles and membrane structures, that are then digested within the lysosomes. In combined activator protein deficient cells nondegradable GSLs on the surface of intralysosomal vesicles protect them against lysosomal digestion. Mice with disrupted genes for activator proteins (SAP precursor -/-, GM2A -/-) as well as disrupted genes for ganglioside GM2 degrading hexosaminidases (HEXA -/-, HEXB -/-) turned out to be useful models for known human diseases whereas double knock out mice (HEXA -/- and HEXB -/-) show a new phenotype of both mucopolysaccharidosis and gangliosidosis.
13

On the character and functions of sphingolipids

67%
Karlsson K. A.
Acta Biochimica Polonica
|
1998
|
tom 45
|
nr 2
Sphingolipids form a large group of membrane lipids showing a diversity of molecular species. Specific functions associated with the saccharide part of glycosphingolipids including co-receptor functions, cell homing phenomena, and attachment by microbes and microbial toxins may not be unique for sphingolipids. However, there are saccharides which appear only in ceramide-bound form and not in other glycoconjugates, and such glycolipids have often been selected as attachment sites by microbes. During the last few years convincing evidence has been presented in favor of ceramide and sphingosine being signaling molecules for various cell functions. The influence of sphingolipids (ceramide) on the properties of the membrane bilayer is still largely unknown. However, based on the structure of ceramide and some experimental evidence one may formulate its role in membrane stability and barrier properties determined by hydrogen bonding in the amide region of ceramide. Furthermore, a natural variation in the number of hydroxyl groups (of fatty acid and long-chain base) may be important for regulation of the potential hydrogen bonds.
14

Implication of glycolipids in lens fiber development

67%
Ogiso M.
Acta Biochimica Polonica
|
1998
|
tom 45
|
nr 2
Mammalian lens contains Lewisx, sialyl-Lewisx and α-galactosyl epitopes in neolacto-series glycosphingolipids. The expression of these three epitopes is not observed in lens epithelial cells, but is immunohistochemically detected in the inner cortical fibers and the lens nucleus. In embryonic chick lens, sialyl-Lewisx-containing gangliosides were also detected in the transitional zone and elongating lens fibers. Thus, the Lewisx, sialyl-Lewisx and α- galactosyl epitopes may be associated with the differentiation and maturation of lens epithelial cells to lens fibers.
15

The levels of glycosphingolipids, ceramides, sialic acid and glycogen are changed in plasma membranes of rat platelets harvested during recovery from immune-mediated thrombocytopenia

67%
Zdebska E., Soszynska B., Dobrowolski Z., Koscielak J.
Acta Biochimica Polonica
|
1996
|
tom 43
|
nr 3
Plasma membranes of rat platelets produced at normal platelet counts and during early recovery from immune-mediated thrombocytopenia were examined for the contents of carbohydrates, lipids and glycosphingolipids. Glucosylceramide, two monosialo-gangliosides and one disialo-ganglioside were found to be the major glycosphingolipids of platelets. During thrombocytopenia the contents of these glycosphingolipids as well as of ceramides were several fold elevated. Among carbohydrate constituents of platelets and platelet plasma membranes, glycogen content was increased and that of sialic acid decreased. These results are discussed in the light of literature data on relevant biochemical characteristics of megakaryocytes at different stages of maturation and on thrombopoiesis during acute experimental thrombocytopenia.
16

Contents of total and protein-bound carbohydrates are low in leukemic leucocytes from patients with acute myelogenous leukemia

67%
Smolenska-Sym G., Zdebska E., Golaszewska E., Wozniak J., Durzynski T., Maj S., Mokras U., Koscielak J.
Acta Biochimica Polonica
|
1998
|
tom 45
|
nr 2
Leukemic leukocytes from 12 patients with acute myelogenous leukemia (AML) and two patients with chronic myelogenous leukemia (CML) were isolated by centrifugations in Percoll gradients, and examined for total carbohydrates. In leukemic leukocytes from 10 of these patients ceramide-bound carbohydrates were also determined. Protein-bound carbohydrates were calculated by subtraction of ceramide-bound carbohydrates from total carbohydrates. In all samples analysed the contents of total and protein-bound carbohydrates were much lower in leukemic leukocytes than in normal neutrophils, irrespective whether the results were expressed relative to protein, DNA, cell number or dry mass. For immature leukemic cells of MO-M1 phenotype differences up to 10-fold were observed. Contents of ceramide-bound carbohydrates, i.e. those of neutral and acidic glycosphingolipids (GSLs) were also low in leukemic cells. However, when GSL carbohydrates were calculated as percentage of total carbohydrates, GSLs in leukemic leukocytes were elevated in half of the AML patients but depressed in the other half. The results are discussed in the light of the hypothesis on GSL function by one of us (Kościelak J., 1986, Glycoconjugate J. 3, 95-108). According to one element of the hypothesis, during cell differentiation newly synthesized glycoproteins (GPs) that perform specific functions are added to house-keeping GPs that are present in plasma membranes of all types of cells. Thus, during differentiation, the GP content of the cell membrane should increase and that of the so called "membrane packing" glycosphingolipids should decrease.
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.