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PubMed1987

Reception-mediated phagocytosis of yeast by macrophage polykarions.

1. The phagocytic capacity of polynuclear macrophages (PNM) produced by intraperitoneal implants in mice was analyzed and compared with that of the mononuclear macrophage (M luminal diameter). The ability of PNM and M luminal diameter to interiorize aldehyde-fixed Saccharomyces cerevisiae is described. 2. PNM containing two to five nuclei and M luminal diameter exhibited a similar time course of phagocytosis. The phagocytic index reached a plateau from 30 to 60 min after exposure to yeast. 3. Mannose, mannan extracted from yeast and horseradish peroxidase inhibited yeast phagocytosis by PNM and M luminal diameter subpopulations to a similar extent. 4. Amino sugars (glucosamine, N-acetylglucosamine, galactosamine and N-acetylgalactosamine) caused similar reductions in the phagocytic indices of PNM and M luminal diameter. 5. The presence of monosaccharides (glucose, galactose, fructose and mannitol) did not alter the phagocytic capacity of either type of phagocyte. 6. Neither opsonin-dependent ingestion of sheep red blood cells nor ingestion of aldehyde-fixed cells by PNM or M luminal diameter is affected by mannose, suggesting that these processes involve internalization pathways different from the mannose-hexosamine recognition system. 7. Trypsin sensitivity, temperature dependence and divalent cation requirements for PNM phagocytosis were comparable to those of the M luminal diameter. 8. The similarities of the PNM to their mononuclear precursors suggest that the mannose-hexosamine receptor was preserved after polykaryon formation.

Animals↗
PubMedDate not supplied

[Glycosaminoglycan levels in normal and degenerative articular cartilage of people of different ages].

Content of glycosaminoglycans in normal and degenerative joint cartilage of various old persons from birth up to senile age was studied by means of estimation of uronic acids, hexoses and hexosamines. In normal cartilage content of hexosamines did not alter with age but concentration of uronic acids was gradually decreased especially distinct at the senile age. Content of hexoses was increased from birth up to 35 years old age and then it was decreased. In degeneratively impaired cartilage content of glycosaminoglycans was decreased; content of all three carbohydrates studied was lesser in the impaired cartilage as compared with normal tissue from persons of the same age.

Adolescent↗
PubMed1986

A large chondroitin sulfate proteoglycan (PG-M) synthesized before chondrogenesis in the limb bud of chick embryo.

Extraction of stage 22-23 chick embryo limb buds that had been metabolically labeled with [35S]sulfate yielded heparan sulfate proteoglycan, small chondroitin sulfate proteoglycan, and large chondroitin sulfate proteoglycan (designated PG-M). PG-M constituted over 60% of the total macromolecular [35S]sulfates. It was larger in hydrodynamic size, richer in protein, and contained fewer chondroitin sulfate chains as compared to the predominant proteoglycan (PG-H, Mr congruent to 1.5 X 10(6)) of chick embryo cartilage. The chondroitin sulfate chains were notable for their large size (Mr greater than or equal to 60,000) and high content of nonsulfated chondroitin units (about 20% of the total hexosamine). Hexosamine-containing chains corresponding in size to N-linked and O-linked oligosaccharides were also present. The core protein was rich in serine, glutamic acid (glutamine), and glycine which together comprised about 38% of the total amino acids. Following chondroitinase AC II (or ABC) digestion, core molecules were obtained which migrated on sodium dodecyl sulfate gel electrophoresis as a doublet of bands with approximately Mr = 550,000 (major) and 500,000, respectively. The Mr = 550,000 core glycoprotein was structurally different from the core glycoprotein (Mr congruent to 400,000) of PG-H, as ascertained by tryptic peptide mapping and immunochemical criteria. Immunofluorescent localization of PG-M showed that the intensity of PG-M staining progressively became higher in the core mesenchyme region than in the peripheral loose mesenchyme, closely following the condensation of mesenchymal cells. Since the cell condensation process has been shown to begin with the increase of fibronectin and type I collagen concentration, the similar change in PG-M distribution suggests that PG-M plays an important role in the cell condensation process by means of its interaction with fibronectin and type I collagen.

Animals↗
PubMed1972

Gangliosides of human, bovine, and rabbit plasma.

Gangliosides were isolated from human, bovine, and rabbit plasma and were quantified by gas-liquid chromatography. Purification was achieved by sequential use of partitioning in solvents, DEAE-Sephadex chromatography, base treatment, and silicic acid chromatography. Human and bovine plasma yielded slightly more than 1 micro mole of lipid-bound sialic acid/100 ml; for rabbit plasma the value was 0.28 micro mole/100 ml. The total bovine plasma ganglioside fraction contained equal amounts of N-acetylneuraminic and N-glycolylneuraminic acids, rabbit plasma gangliosides had about 1% of the latter, and the human plasma sample contained only the former. Thin-layer chromatography revealed important differences among the plasmas from the three species, but all possessed hematosides and hexosamine-containing gangliosides. The approximate ratios of these two categories, based on sialic acid content, were (hematosides: hexosamine-type): human, 2:1; rabbit, 3:2; and bovine, 2:3. The fatty acid compositions of both categories were characteristic of extraneural gangliosides and included six major acids: palmitic, stearic, behenic, tricosanoic, lignoceric, and nervonic. The major long-chain base in each sample was sphingosine, while only a trace of the C(20) isomer was detected.

Animals↗
PubMed1975

[Obtaining purified preparations of individual Shigella newcastle K- and O-antigens by using an ultracentrifugation method].

A modified method of obtaining the purified K- and O-antigens of Sh. newcastle with the use of ultracentrifugation is described. Serologically individual K- and O-antigens were obtained and their chemical composition was studied. Polysaccharide of the K-antigen consisted of the galacturonic acid, galactose, glucose, rhamnose xylose and hexosamine; it contained no heptoses. The O-antigen contained galactose, glucose, mannose, rhamnose, heptose and hexosamine; in difference to K-antigen was equal to 150000--160000. Thus, the K- and the O-antigen differed not only in the electrophoretic and diffuse mobility and immunological specificity, but also in the chemical composition.

Antigens, Bacterial↗
PubMed1982

Changes in cell cultures of bovine corneal endothelium cells as related to donor age and number of passages in vitro.

Aging changes of the acidic glycosaminoglycans (aGAG) were investigated in bovine corneal endothelium cells grown in vitro, using histochemical methods and the determination of hexosamine and uronic acid. The time interval between trypsination and confluency of the monolayer and the cell counts at different time intervals of the same passage number served as parameters for the proliferation capacity of the cultures. A cell line, derived from the eye of a 1,5 year old cattle showed a low proliferation capacity in the first 9 passages, which increased until the 15th passage, to decrease thereafter until the 29th passage. In cells from eyes aged 11 and 12 years respectively the initial proliferation capacity was very low to reach the same values as in cultures of the young eye at the 10th passage but remained constant thereafter. Chromosome counts showed an increased number of hyperploids in late passages of cells from the aging eye with counts around 4n-8n increased to 17% as compared to 5% in the cells derived from the young eye. The cell densities were increased in cultures of high passage numbers. Histochemically the aGAG were shown in the cell nucleus, and the cytoplasm as well as in the intercellular space. In the nuclei of cells from aging eyes and in late passage cells of the young eye they showed an increased resistance against resting hyaluronidase. The hexosamine and uronic acid values were high in early passages of cultures from the young eye and decreased in late passages of the young eye as well as in early passages of cells from the aging eyes. The changes in the aGAG as well as the changes in the cell proliferation are similar comparing early passage cells of aging eyes to late passage cells of the young eyes. But the aGAG changes are more pronounced in cells of eyes aged in vivo. In the eye the proliferation of the corneal endothelium cells is inhibited. As such these cells provide a useful model to comparing in vivo-aging changes of resting cells to changes of the same cells proliferating in vitro.

Aging↗
PubMed1984

Regulatory aspects of glycosaminoglycan biosynthesis.

The control of glycosaminoglycan biosynthesis was investigated by studying the kinetic and regulatory properties of some enzymes involved in the formation of UDP-sugar precursors: UDP-N-acetylglucosamine 4'-epimerase, catalyzing the interconversion of hexosamine precursors and UDP-glucose dehydrogenase and UDP-glucose 4'-epimerase, utilizing UDP-glucose for the formation of uronic acid and galactose precursors. The study was carried out in tissues with different glycosaminoglycan production: bovine cornea, producing both chondroitin sulfate and keratan sulfate, and newborn-pig epiphysial-plate cartilage, producing mostly chondroitin sulfate. The biosynthesis of hexosamine precursors appeared to be regulated by the value of the NAD/NADH ratio. This control mechanism regulated also the activities of both UDP-glucose dehydrogenase and UDP-glucose 4'-epimerase and, therefore, it could correlate the biosynthesis of glycosaminoglycan precursors with the redox activity of the cell. At the level of UDP-glucose utilization two other control mechanisms were demonstrated: the different affinities of UDP-glucose dehydrogenase and UDP-glucose 4'-epimerase for UDP-glucose in tissues with different glycosaminoglycan production and the cellular concentration of UDP-xylose. This sugar-nucleotide inhibited UDP-glucose dehydrogenase, but did not affect the UDP-glucose 4'-epimerase activity; therefore, and increase of its cellular concentration may result in a decreased chondroitin sulfate synthesis and in an increased keratan sulfate formation.

Animals↗
PubMed1976

Serum glycoproteins in autoimmune diseases.

The concentration of IgA, IgG, IgM, coeruloplasmin, alpha-2-macroglobulin, beta-1-C-globulin, transferrin as well as of alpha-2-haptoglobin, orosomucoid and haemopexin has been studied in the serum of patients with disseminated lupus erythematosus, chronic progressive polyarthritis and immunopathological syndromes. The concentration of the carbohydrate components bound to serum proteins was also determined. In disseminated lupus erythematosus, the concentration of IgA, IgG, IgM, coeruloplasmin, and hexose, hexosamine and sialic acid bound to proteins, as well as of seromucoid was increased. In chronic progressive polyarthritis the IgA, IgG, IgM, coeruloplasmin, alpha-2-macroglobulin and beta-1-C-globulin concentration and the carbohydrate components bound to serum proteins rose. In immunopathological syndromes, too, the serum IgA, IgG, IgM, coeruloplasmin, and protein-bound hexosamine and sialic acid levels were increased. Under the effect of treatment, the elevated glycoprotein concentrations usually decrease, but the level of carbohydrate components bound to serum proteins hardly changes. The pathogenic and diagnostic significance of serum glycoproteins is discussed.

Adult↗
PubMed1981

Antiulcer effect of geranylgeranylacetone, a new acyclic polyisoprenoid on experimentally induced gastric and duodenal ulcers in rats.

Antinuclear effects of geranylgeranylacetone (GGA), new acyclic polyisoprenoid, on several types of experimental gastric and duodenal ulcers were studied in rats. The prophylactic administration of GGA (50--200 mg/kg p.o. or 12.5--50 mg/kg i.p.) reduced the gastric ulcers induced by the exposure to cold-restraint stress and by the administration of indomethacin, acetylsalicylic acid (ASA), prednisolone or reserpine and the duodenal ulcer after the administration of cysteamine, although it was not effective against Shay's ulcer. The curative treatment with GGA accelerated the healing process of the gastric ulcers induced by the topical application of acetic acid or thermocautery and by the administration of ASA with the exposure to cold-restraint stress. The antinuclear effect of GGA was more distinct than that of gefarnate in all types of experimental models studied. Carbenoxolone effectively reduced the gastric ulcer formation by cold-restraint stress when it was administered i.p. but not p.o., whereas GGA was effective either i.p. or p.o. GGA and gefarnate did not affect the gastric secretion in pylorus-ligated rats, whereas carbenoxolone definitely reduced the secretion of gastric juice and acid. Hexosamine content in the stomach was reduced by the exposure to cold-restraint stress. The pretreatment with GGA prevented the reduction in hexosamine contents in the superepithelial mucous layer and mucosal layer. These results may suggest a high possibility that GGA is useful for clinical treatment of peptic ulcers, probably through a mechanism of increasing defence force of the gastric mucosa.

Animals↗
PubMed1980

[Effect of diet and microflora on amino sugars in the digestive contents and faeces of rats, lambs and preruminant calves].

Glucosamine (Glc NH2) and galactosamine (Gal NH2) were determined by an automatized chromatographic method in samples from digestive contents and faeces. Germfree lambs and rats as well as conventional preruminant calves, lambs and rats were used in the experiments. The rats were fed an irradiated casein diet, the lambs UHT milk and the preruminant calves various diets (table 1). Concentrations of Glc NH2 and of Gal NH2 reached 6 g/16 g of N in the caecal contents and the faeces of germfree rats (table 2). Concentrations of Gal NH2 were 7 to 12 times lower and those of Glc NH2 4 times lower in conventional rats. In lambs, the amino sugar concentrations (table 3) found in the stomach contents resembled those supplied by the milk. In contrast, in the large intestine and the faeces, the concentration of amino sugars was very high. In conventional lambs, those concentrations were 8 to 4 times lower. For ruminant calves, the concentrations of amino sugars (table 4) were greater in the ileal contents than in the faeces. They reached that of meconium when the calves were fed milk. The lowest values were observed in the faeces of calves fed soya, colostrum or fish diets which are less digestible than milk. In germfree animals, the hexosamines were endogenous. In conventional animals, bacterial metabolism led to an increase in faecal Glc NH2/Gal NH2. In the calves fed soya or fish diets, the hexosamine content in the faeces was low owing to the dilution of bacterial and endogenous mucoproteins by the undigested dietary proteins.

Animals↗
PubMedDate not supplied

[Connective tissue proteins from an erosive stomach ulcer].

Complex biochemical study of the connective tissue of the stomach and liver of white rats under experimental gastroduodenal ulcer and of the effect of new high-protein vitaminized product "Bioctim" and ethonium has been carried out. The content of noncollagen proteins was determined from tyrosine, that of total glycoproteins from hexosamine, proteoglycans--from hexuronic acids, collagen--from oxyproline. The induced pathology is observed to result in the decrease of the concentration of tyrosine of hexosamines, hexuronic acids and oxyproline. A combined application of the above drugs takes most efficient favourable effect on the biochemical processes in the connective tissue of the stomach under given pathology.

Animals↗
PubMed1996

Changes in tubular membrane glycosylation in diabetic, insulin and thyroxin treated rat kidneys.

The effect of insulin, thyroxine and alloxan induced diabetes has been studied on brush border membrane glycosylation in rat kidneys. Expressed on dry weight basis, the membrane protein was elevated in insulin, thyroxine and diabetic membranes compared to the control group. Sialic acid content of the membranes was significantly reduced in insulin and thyroxine injected animals whereas fucose level was unaffected under these conditions. Brush border fucose content was significantly reduced in diabetic animals but sialic acid content was unaffected. Membrane hexose and hexosamines levels were unaltered by hormone treatments, but in diabetic rats hexosamine level was significantly reduced. The binding of radiolabelled UEA, WGA, PNA to purified brush borders corroborated changes in membrane saccharides. These findings suggest the role of hormones in membrane glycosylation of rat kidney tubules.

Animals↗
PubMed1977

Biochemical investigations of retinotectal specificity.

An in vitro assay for retinotectal specificity has been described. The results show that, in the chick embryo, cells dissociated from the dorsal retina preferentially adhered to ventral tectal surfaces while cells from the ventral retina preferentially adhered to dorsal tectal surfaces. These adhesive preferences thus mimic the retinotectal specificity observed in vivo. The assay has been extended for use with plasma membrane preparations from retinal cells. Experiments in which retinal cells or tectal surfaces were treated with purified proteases and glycosidases have partially characterized the moieties responsible for the observed specificities. These results are consistent with a double gradient in the dorsal-ventral axis of complementary proteins and carbohydrates. The carbohydrate moiety would be expected to terminate in an acetylated hexosamine and to be more concentrated dorsally in both retina and tectum. A protein that is complementary to the hexosamine terminus would be localized in the ventral part of retina and tectum.

Animals↗
PubMed1998

Effects of hypothyroidism and hyperthyroidism on serum glycoproteins in experimental rats.

Hypothyroidism and hyperthyroidism were induced in adult female Sprague Dawley rats by feeding 0.05% propylthiouracil and 0.0012% L-thyroxine in drinking water. Contents of protein-bound hexose, fucose, hexosamine and sialic acid in serum were estimated in experimental rats. The results showed an increase in the protein bound hexose, fucose, hexosamine and sialic acid levels in hypothyroid rats and decrease in hyperthyroid rats. The increased content of serum glycoproteins in hypothyroid rats might possibly have come from disruptions of membranes. Depleted glycoproteins in hyperthyroid animals might be due to increase in depolymerisations of glycoproteins and accelerated secretion of glycoproteins with urine.

Animals↗
PubMed1965

STUDIES ON THE MUCIN DERIVED FROM HUMAN COLLOID BREAST CARCINOMA.

1. A non-diffusible mucoid, showing a single peak in the ultracentrifuge, was isolated from human colloid breast carcinoma by treatment with trypsin and pepsin. The material contained threonine, leucine (isoleucine), valine, proline, glycine and glutamic acid in the approximate molar proportions 5:1:1:2:1:1. Smaller amounts of aspartic acid and serine were also found. For each 5 threonine residues, 6 N-acetylgalactosamine and 3-4 galactose residues were present. 2. The mucoid possessed reducing properties by the Park & Johnson (1949) procedure; these were attributable to the action of mild alkali, as employed in this procedure. Mild alkaline treatment by the Aminoff, Morgan & Watkins (1952) procedure gave rise to a diffusible N-acetylgalactosamine chromophore that gave an enhanced colour with Ehrlich's reagent. That galactosyl-(1-->3)-N-acetylgalactosamine residues were liberated was supported by periodate studies. 3. Alkaline liberation of hexosamine residues was accompanied by a specific destruction of threonine. After 40 min. at 100 degrees in 0.18 n-lithium hydroxide, both moieties had almost completely disappeared from the ninhydrin-positive components formed on subsequent acid hydrolysis. Glycine and alpha-oxobutyric acid were present in the acid hydrolysate, showing that both possible pathways of a beta-elimination reaction were involved. Formation of diffusible peptide on very mild alkaline treatment was attributable to the rupture of the original peptide core, necessitated by the second of these two pathways. 4. Hydroxamate formation on treatment with hydroxylamine showed the presence of carbohydrate linkage to glutamic acid or aspartic acid residues or both. This could account for the single N-acetylgalactosamine residue not linked to threonine. 5. The native mucin contained sialic acid, which was cleaved by the acid environment used in the treatment with pepsin. A statistical model of the mucin would require each prosthetic group to be linked, via N-acetylgalactosamine, to threonine, which would occupy every alternate position among the amino acids in the peptide core.

Adenocarcinoma, Mucinous↗
PubMed1964

EXTRACTION AND PURIFICATION OF ENDOTOXIN FROM ENTEROBACTERIACEAE: A COMPARISON OF SELECTED METHODS AND SOURCES.

Fukushi, K. (National Institute of Allergy and Infectious Diseases, Rocky Mountain Laboratory, Hamilton, Mont.), R. L. Anacker, W. T. Haskins, M. Landy, K. C. Milner, and E. Ribi. Extraction and purification of endotoxin from Enterobacteriaceae: a comparison of selected methods and sources. J. Bacteriol. 87:391-400. 1964.-Endotoxins containing only 0.2% N (accounted for by amino sugars) and 2% ester- and amide-linked fatty acids (calculated as palmitic acid) were prepared from Salmonella enteritidis. These products were of high biological potency, and were rapidly destroyed by acid hydrolysis. Equally potent acid-susceptible products were derived from different strains of Escherichia coli and Serratia marcescens. No correlation was evident between potency and content of nitrogen, fatty acids, and hexosamine; however, low values for carbohydrate were invariably associated with reduced endotoxic activity. Factors such as strain, method of cultivation, and extraction procedure markedly affected the chemical composition and activity of primary extracts. Results are given which demonstrate significant advantages in the use of cell walls for the isolation and purification of endotoxins.

Carbohydrates↗
PubMed1964

DEPENDENCE OF THE CONTENT OF CELL ENVELOPES ON THE GROWTH RATE OF BACILLUS MEGATERIUM.

Sud, I. J. (Tufts University School of Medicine, Boston, Mass.), and M. Schaechter. Dependence of the content of cell envelopes on the growth rate of Bacillus megaterium. J. Bacteriol. 88:1612-1617. 1964.-The amount of cell-wall and cell-membrane material was measured in Bacillus megaterium growing at different steady-state rates. On a dry weight basis, the content of wall hexosamine and diaminopimelic acid, and of membrane lipid phosphorus was found to be inversely proportional to the rate of growth. During the transition from slow to fast growth, the synthesis of envelope materials showed a lag of 20 to 30 min. Possible implications of these findings are discussed in terms of regulatory mechanism.

Bacillus megaterium↗
PubMed1965

PREPARATION AND PROPERTIES OF A VI ANTIGEN-DEGRADING ENZYME.

Baker, Edgar E. (Boston University School of Medicine, Boston, Mass.), and Roberta E. Whiteside. Preparation and properties of a Vi antigen-degrading enzyme. J. Bacteriol. 89:1217-1224. 1965.-Vi antigen can be hydrolyzed by an inducible enzyme produced by a microorganism isolated from soil. The organism can be identified as Bacillus sphaericus. The enzyme in the culture supernatant fluid can be concentrated and partially purified by precipitation with ammonium sulfate at 50% of saturation. The partially purified enzyme is relatively stable. Incubation of the enzyme with Vi antigen causes a rapid loss of serological activity, a decrease in viscosity, the loss of ability to precipitate albumin at pH 4.0, and the production of reducing sugar and hexosamine. Optimal conditions for enzyme action on Vi antigen are pH 8.4 and 40 C. The reaction rate is independent of the substrate concentration. Intact protein and calcium activates the Vi antigen-enzyme system. The enzyme is not inhibited by its reaction products.

Bacillus↗