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PubMed1979

Atypical leukodystrophy with accumulations of sulfatide and mucopolysaccharide.

1. Follow-up studies of two siblings with mental retardation, progressive paraplegia and dementia were reported. 2. The brain and visceral organs of a patient (elder brother) who died recently were investigated histopathologically, electronmicroscopically and neurochemically. a. Moderate, diffuse demyelination occurred throughout the white matter of the central nervous system. b. Two abnormal materials were deposited in the white matter: one showed metachromasia containing sulfatide and another had staining characteristics of acid mucopolysaccharide histochemically. Electronmicroscopically, the former was a conglomerate of electron-dense materials of various degrees and the latter had a membrane-limited granular structure. The myocardium contained the same mucopolysaccharide material as that in the brain. c. Slight increase of sulfatide was found in the cerebral white matter. Arylsulfatase A activities were preserved in the brain as well as in the liver. Contents of hexosamine and uronic acid in the white matter were about three or five times as much as that of the controls. Electrophoresis on cellulose acetate membrane showed that acid glucopeptide was the main component of the mucopolysaccharide extracted from the brain.

Adult↗
PubMed1976

Chemical compositions of brain and myelin in two patients with multiple sulphatase deficiency (a variant form of metachromatic leukodystrophy).

The lipid composition of the brain, including myelin, was studied in detail in two cases with a variant form of metachromatic leukodystrophy (multiple sulphatase deficiency type). In the white matter, the sulphatide concentration was 3-4 times higher than the normal level in both cases. There was a significant accumulation of cholesterol sulphate in the brain, liver and kidney of both cases. The ganglioside pattern in the grey and white matter was abnormal, with a higher proportion of GM3, GM2 and GD3-gangliosides. Non-lipid hexosamine contents were increased 1.5-2 times in brain, 8-10 times in liver and 2-3 times in kidney. Increased amounts of glucocerobroside, ceramide lactoside and ceramide trihexoside were present in grey and white matter of both cases. Recovery of purified myelin from two patients' brains was much less than from control (1-2% in case 1 and 20-30% in case 2). The lipid composition of myelin was almost normal except for a higher proportion of sulphatide, with a decreased amount of cerebroside. The fatty acid compositions of myelin sulphatide and sphingomyelin were almost normal, while non-hydroxy fatty acids of cerebroside contained less long-chain fatty acids, as characterized by a significant increase of C16:0 and C18:0 fatty acids. The myelin polypeptide pattern by SDS-disc gel electrophoresis showed a relative decrease of basic protein and of proteolipid protein. A possible mechanism of myelin loss in MSD is discussed.

Antigens, CD↗
PubMedDate not supplied

Changes in (Na+ + K+) ATPase activity and the composition of surface carbohydrates in erythrocyte membranes in alcoholics.

(Na+ + K+)ATPase activity and sensitivity to the inhibitory effect of ethanol and noradrenaline in vitro as well as the concentrations of sialic acid, galactose, and hexosamine were determined in erythrocyte membranes in 20 healthy controls and in 20 alcoholic patients within 24 hr of withdrawal. Basal (Na+ + K+)ATPase activity, the sensitivity of the enzyme to inhibition by ethanol and noradrenaline added in vitro, and the concentrations of sialic acid and galactose were significantly reduced in the patients (p less than 0.0005). All of these abnormalities were significantly correlated to each other as well as to the estimated daily quantity of ethanol consumed. After enzymatic removal of terminal sialic acid and terminal and sialic acid-bound beta-galactose, the (Na+ + K+)ATPase differences between the patients and the controls were eliminated. The results showed that the previously reported reduced inhibition of (Na+ + K+)ATPase by ethanol in the presence of noradrenaline in brain membranes in chronically ethanol-fed animals is also found in erythrocyte membranes in alcoholic humans. Abnormal carbohydrate composition of glycolipids and/or glycoproteins of the membrane surface appeared to be related to the (Na+ + K+)ATPase changes, possibly due to interference either with K+ transport or surface electrostatics or, directly or indirectly, with the conformation of (Na+ + K+)ATPase.

Adult↗
PubMed1994

Molecular genetical and phenotypical analysis of the gerM spore germination gene of Bacillus subtilis 168.

The gerM gene, encoding a single product of 22.5 kDa, has been identified by subcloning and sequencing of DNA recovered from adjacent to a Tn917 insertion. The gene product has a potential lipoprotein signal sequence, but otherwise has no homology to known sequences. Spores of the gerM mutant were more heat sensitive than wild-type, but their dipicolinic acid content was normal. The level of cortical peptidoglycan in mutant spores is also normal but release at germination of hexosamine-containing fragments, the breakdown products of cortex degradation, is less complete than wild-type. The sporulation, resistance and germination phenotypes of the gerM mutant would be consistent with the gene product having a role, either directly or indirectly, in peptidoglycan synthesis during sporulation.

Amino Acid Sequence↗
PubMed1996

Saliva composition in children and young adults with Papillon-Lefèvre syndrome.

The aim of the present study was to evaluate the salivary secretion rate and composition in a group of 16 children and young adults (6-27 years) with Papillon-Lefèvre Syndrome (PLS), and to compare the findings with a group (n = 16) of healthy controls. Unstimulated and stimulated whole saliva was collected at least 2 h after meals and the secretion rate determined. The stimulated saliva was assessed for buffer capacity, total protein, peroxidase and hexosamine, while the unstimulated samples were evaluated for total protein, lysozyme, thiocyanate, lactoferrin and salivary IgA. Both the unstimulated (p < 0.01) and stimulated (p < 0.05) saliva secretion rates were significantly lower among the PLS patients compared with the controls. Furthermore salivary buffer capacity was significantly (p < 0.01) lower in the PLS patients. The total protein content in saliva was comparatively high in the study group, while the concentrations of immunoglobulins and non-immunoglobulins were within normal ranges. When calculating the output of the assessed antimicrobial factors, the mean peroxidase level in stimulated whole saliva was found to be significantly (p < 0.01) lower in the PLS patients than in the healthy controls. In conclusion, the present study indicates an impaired water secretion and a somewhat altered saliva gland function in children and young adults with PLS.

Adolescent↗
PubMed1994

Effects of the beta-adrenoceptor antagonists atenolol and propranolol on human unstimulated whole saliva flow rate and protein composition.

The effects of 1-wk medication with two beta-adrenoceptor antagonists on unstimulated whole saliva flow rate and protein composition were evaluated in 11 healthy young men in a randomized, double-blind, placebo-controlled, cross-over study. Unstimulated whole saliva was collected before each treatment period and then again after 7 days. The saliva was assessed for flow rate, total protein, and hexosamine and sialic acid concentrations and for amylase activity. No significant effect on saliva secretion rate was found. A statistically significant reduction of salivary total proteins was registered during atenolol medication. The amylase activity decreased significantly during treatment with both atenolol and propranolol. Significant changes of the calculated ratios of sialic acid/hexosamine and hexosamine/total protein indicated an alteration in glandular protein synthesis after atenolol treatment.

Adult↗
PubMed1977

The influence of lithium on water binding ability, consistency and macromolecules in the rat brain.

Wistar male rats were treated with lithium for 50, 80, and 120 days, respectively. Lithium was added to the diet (40 mmol/kg of diet), the plasma lithium concentration being in the range of 0.55-0.70 mmol/1 of plasma. The treatment caused a significantly more rigid consistency of the brain tissue. The water content and water binding ability in various parts of the brain - measured by a drying course - was unchanged. The content of hexosamine and protein in total brains was significantly decreased (about 10 per cent) after the treatment. The content of chondroitin sulphate in various parts of the brain was unchanged, whereas the content of hyaluronic acid was significantly increased in the cerebellum (25 per cent) and in the thalamic area (20 per cent). The results suggest an influence of lithium on the macromolecules from the extracellular space, causing an alteration of the neuronal function.

Animals↗
PubMed1966

The size of the sucrose, raffinose, and inulin spaces in the gastrocnemius muscle of the rat.

1. The sucrose, raffinose and inulin spaces within the gastrocnemius of the female rat have been estimated at 12.0 +/- 2.2%, 10.7 +/- 0.6%, and 10.0 +/- 0.3% respectively, expressed as a percentage of the total muscle volume.2. The mucopolysaccharide and hexosamine contents of the gastrocnemius have been found to be inversely dependent upon the weight of the muscle.3. The possibility that a relation exists between the saccharide spaces and the muscle musopolysaccharide content has been discussed in terms of saccharide molecular radii.

Animals↗
PubMed1988

Mechanical properties of the lateral collateral ligament: effect of cruciate instability in the rabbit.

Concomitant soft tissue injury resulting from knee instability following cruciate rupture is a serious clinical problem. To study this injury mechanism, the biomechanical properties of the lateral collateral ligament were measured at 0, 4, 8, 12, and 16 weeks post-operatively in rabbits having the anterior and posterior cruciate ligaments sectioned. No significant changes were found in the ligament's cross-sectional area, tensile mechanical response, or in its hexosamine content. The predominant mode of ligament failure was by bone avulsion at the insertion sites (78 percent) with 86 percent of paired limbs failing in a similar manner.

Animals↗
PubMed2001

Complete genome sequence of a virulent isolate of Streptococcus pneumoniae.

The 2,160,837-base pair genome sequence of an isolate of Streptococcus pneumoniae, a Gram-positive pathogen that causes pneumonia, bacteremia, meningitis, and otitis media, contains 2236 predicted coding regions; of these, 1440 (64%) were assigned a biological role. Approximately 5% of the genome is composed of insertion sequences that may contribute to genome rearrangements through uptake of foreign DNA. Extracellular enzyme systems for the metabolism of polysaccharides and hexosamines provide a substantial source of carbon and nitrogen for S. pneumoniae and also damage host tissues and facilitate colonization. A motif identified within the signal peptide of proteins is potentially involved in targeting these proteins to the cell surface of low-guanine/cytosine (GC) Gram-positive species. Several surface-exposed proteins that may serve as potential vaccine candidates were identified. Comparative genome hybridization with DNA arrays revealed strain differences in S. pneumoniae that could contribute to differences in virulence and antigenicity.

Antigens, Bacterial↗
PubMed2006

Role of insulin, adipocyte hormones, and nutrient-sensing pathways in regulating fuel metabolism and energy homeostasis: a nutritional perspective of diabetes, obesity, and cancer.

Traditionally, nutrients such as glucose and amino acids have been viewed as substrates for the generation of high-energy molecules and as precursors for the biosynthesis of macromolecules. However, it is now apparent that nutrients also function as signaling molecules in functionally diverse signal transduction pathways. Glucose and amino acids trigger signaling cascades that regulate various aspects of fuel and energy metabolism and control the growth, proliferation, and survival of cells. Here, we provide a functional and regulatory overview of three well-established nutrient signaling pathways-the hexosamine signaling pathway, the mTOR (mammalian target of rapamycin) signaling pathway, and the adenosine monophosphate-activated protein kinase (AMPK) signaling pathway. Nutrient signaling pathways are interconnected, coupled to insulin signaling, and linked to the release of metabolic hormones from adipose tissue. Thus, nutrient signaling pathways do not function in isolation. Rather, they appear to serve as components of a larger "metabolic regulatory network" that controls fuel and energy metabolism (at the cell, tissue, and whole-body levels) and links nutrient availability with cell growth and proliferation. Understanding the diverse roles of nutrients and delineating nutrient signaling pathways should facilitate drug discovery research and the search for novel therapeutic compounds to prevent and treat various human diseases such as diabetes, obesity, and cancer.

AMP-Activated Protein Kinase Kinases↗
PubMed1974

Comparison of the chemical structure and biological activities of the glycolipids of Salmonella minnesota R595 and Salmonella typhimurium SL1102.

It has been assumed in the past that the lipid moieties of endotoxic lipopolysaccharides are quite similar if not identical. This has been tested in the reported work here, where the chemical composition and biological activities of the glycolipids of two heptoseless Re mutants, Salmonella minnesota R595 and Salmonella typhimurium SL1102, have been studied and compared. The two glycolipids, extracted with chloroform-methanol (4:1), showed identical thin-layer chromatographic patterns. The molar ratios for hexosamine, fatty acids, phosphorus, 2-keto-3-deoxyoctonate, total amines, and total nitrogen of the purified glycolipids were in the same range, but small differences could be established. Both glycolipids contained the same major fatty acids, i.e., lauric, myristic, palmitic, and 3-hydroxymyristic acids, in similar but not identical ratios. On paper electrophoresis, the acid hydrolysates of the two glycolipids showed analogous components. In the determination of molecular weight, whereas S. minnesota R595 glycolipid did not show concentration dependence, the molecular weight measured for S. typhimurium SL1102 increased with its concentration. The molecular weight of the fully endotoxic R595 glycolipid has been found to be 17,000 +/- 1,500. Both glycolipids showed similar activities in the Shwartzman skin reaction, Limulus-lysate clotting assay, mouse lethality, and enhancement of nonspecific resistance, but the R595 preparation appeared to be more active on a weight basis in some parameters than SL1102. Using passive hemagglutination, we observed cross-reactivity between the glycolipids. In the gel-diffusion test, they revealed clear identity. The antiserum against S. minnesota R595 neutralized the Shwartzman skin reactivity not only of R595 but also of SL1102 glycolipid. These results confirm that there are identical immunodeterminant group(s) in the two glycolipids. On the other hand, chemical analytical data for two glycolipids showed only similarities, indicating that although both glycolipids are of comparable chemical nature, differences between them exist.

Antibodies, Bacterial↗
PubMed1975

Characterization of endotoxin from Fusobacterium necrophorun.

Endotoxic lipopolysachharide (LPS) was obtained from phenol-water extraction of cell walls prepared from mass-cultivated Fusobacterium necrophorum. The LPS was relatively free of nucleic acids and low in protein, and constituted about 4% of the cell walls. Upon acid hydrolysis, some of the components detected were hexosamines (7.0%), neutral and reducing sugars (50.5%), heptose (6.4%), 2-keto-3-deoxyoctonate (0.8%), lipid A (21.0%), and phosphorus (1.7%). Under electron microscopy the LPS appeared mainly as ribbon-like trilaminar structures, and upon chemical treatment it displayed a behavior resembling that reported in certain enterobacterial LPS. The LPS was lethal to mice, 11-day-old chicken embryos, and rabbits. Endotoxicity in mice was enhanced at least 1,380-fold by the addition of 12.5 mug of actinomycin D. Induced tolerance to lethal effect of the endotoxin and rapidly acquired resistance to infection by F. necrophrum viable cells were also demonstrated in mice. The endotoxin produced both localized and generalized Shwartzman reactions as well as biphasic pyrogenic responses in rabbits. These results firmly establish the presence of a classical endotoxin in F. necrophorum, thus providing strong support to our recent suggestion that cell wall-associated components may contribute significantly to the pathogenicity of F. necrophorum.

Animals↗
PubMed1976

Relationship of the cell wall composition of group H streptococci and Streptococcus sanguis to their serological properties.

Previous studies indicated the a antigen was widely distributed among strains of Streptococcus sanguis and the group H streptococci. The cell walls of strains containing this antigen had moderate to large quantities of rhamnose, small amounts of phosphorus, and little to no ribitol. The molar ratios of the peptidoglycan amino acids and hexosamines suggested a di-alanyl cross bridge. The homogeneity of the walls of these strains suggested that serological group H can be considered synonymous with S. sanguis. In contrast those strains that did not contain the a antigen had only small amounts of rhamnose in their cell walls, galactosamine and ribitol were always detected, and large quantitites of phosphorus were present. The molar ratios of peptidoglycan components in the latter strains suggested a direct alanyl-lysl cross bridge. Although many of these strains had been classified either as S. sanguis or group H streptococci because of minor serological cross-reactions and similar biochemical properties, the distinct differences between the composition of their cell walls and those of S. sanguis and group H streptococci indicate that they do not belong in this species or group. The cell walls of strains containing the a antigen are relatively homogeneous and therefore it is suggested that cells containing this antigen be considered Lancefield serological group H.

Amino Acids↗
PubMed1972

Characterization of spheroplast membranes of Neisseria meningitidis group B.

Spheroplast membranes (spheroplast envelopes) of strain 2091 of group B Neisseria meningitidis were prepared by a procedure that included lysozyme treatment of the cells and osmotic lysis of the resulting spheroplasts. Electron microscopy revealed that the membranes consisted of two unit layers, generally parallel to each other. The membrane preparation migrated as a single component in a 40 to 70% sucrose gradient and consisted of 62% protein, 28% lipid, 9% ribonucleic acid, small amounts of carbohydrate, hexosamine, and deoxyribonucleic acid. When 1 or 10 mug (dry weight) was injected intravenously into rabbits, a mild pyrogenic reaction was elicited. In immunodiffusion tests, immune rabbit serum prepared against spheroplast membranes produced three major precipitin lines, with the homologous antigen solubilized with sodium dodecyl sulfate, and a single line with untreated antigen. The immune serum also reacted with a cell wall antigen, and to a lesser extent with some of the cytoplasmic antigens. Succinate dehydrogenase and reduced nicotinamide adenine dinucleotide (NADH) oxidase activities were found to be associated with the spheroplast membranes. NADH dehydrogenase also was associated with the membranes but was gradually released and recovered in other fractions. Glutamate-oxaloacetate transaminase, glutamate, glucose-6-phosphate, and isocitrate dehydrogenase activities were not found in the membrane preparation. About one-third of these enzymatic activities were recovered in the supernatant fluid after the sedimentation of the spheroplasts and two-thirds were recovered in the cytoplasmic fraction. N-acetylneuraminic acid (NAN)-condensing enzyme and cytidine monophosphate-NAN synthesizing enzyme also were identified in this organism. These enzymes were not associated with the membranes and were recovered from extracts from whole cells, spheroplasts, or cells exposed to osmotic shock, as well as from spheroplast supernatant and shock fluids. It is concluded that the spheroplast membranes of the strain of meningococci used in these studies are typical of those recovered from gram-negative bacteria.

Animals↗
PubMed1987

Purification and partial characterization of the capsular polymer of Haemophilus pleuropneumoniae serotype 5.

The capsular polymer (CP) of Haemophilus pleuropneumoniae serotype 5 was purified, and its chemical composition was analyzed. Radioimmunoassay experiments showed that the maximum amount of CP could be obtained from broth cultures of bacteria in the late stationary phase, rather than from bacteria washed off agar plates. The CP was precipitated from culture supernatant with 5 mM hexadecyltrimethylammonium bromide (Cetavlon) and solubilized with 0.4 M NaCl. Ninety percent of the CP in the culture supernatant was precipitated with Cetavlon, although some material remained insoluble after NaCl extraction. The CP was further purified by phenol extraction, ultracentrifugation, and Sepharose CL-4B gel filtration. The Kav of the CP from Sepharose CL-4B chromatography was 0.33. The CP preparation contained 85% hexosamine, 12% hexose, 3% phosphate, 0.17% protein, 0.20% nucleic acid, and 0.01% endotoxin. Thin-layer chromatography, an amino acid analyzer, and a glucose oxidase colorimetric kit were used to identify the sugar components of the hydrolyzed CP as glucosamine and glucose. Analysis of the native CP by 13C nuclear magnetic resonance indicated that amino, N-acetyl, and carboxyl groups were present and that the CP was a disaccharide.

Antigens, Bacterial↗
PubMed1974

Purification, composition, and serological characterization of histoplasmin-H and M antigens.

To obtain purified H and M antigens suitable as primary standards in the serological diagnosis of histoplasmosis by agar gel double-diffusion tests, H and M reactive components of histoplasmin were fractionated by column chromatography by using Sephadex G-100, Sephadex G-200, and diethylaminoethyl cellulose. Six fractions from diethylaminoethyl cellulose were reactive in agar gel double-diffusion, complement fixation, and capillary precipitin tests. When examined by electrophoresis on acrylamide gel, one M antigen (fraction 2, molecular weight greater than 200,000) and two H antigens (fractions 5 and 6, molecular weight greater than 200,000) each gave essentially a single protein band. In agar gel double-diffusion and complement fixation tests with sera from patients with proven cases of histoplasmosis, blastomycosis, or coccidioidomycosis, these two fractions of H antigen and the one of M antigen reacted only with sera from proven or suspect cases of histoplasmosis and showed reactivity with those sera known to contain only the anti-H or anti-M antibody, respectively. Fraction 2 (M antigen) and fractions 5 and 6 (H antigens) had carbohydrate-to-protein ratios of 1.60, 0.77 and 0.78, respectively. Both antigens contained galactose, glucose, mannose, and hexosamine, with mannose being the predominant sugar. Fraction 2 was characterized by a high proline and glucose content, whereas fractions 5 and 6 contained higher concentrations of galactose, mannose, glycine, and alanine. Each of these products appeared to separate into two active fractions, one of a molecular weight greater than 200,000 and one of a molecular weight less than 35,000. The M antigen component of fraction 2 was still characterized by a high proline content, whereas the H antigen components of fractions 5 and 6 had a high content of glutamic acid, serine, glycine, and proline.

Antigens, Fungal↗
PubMed1969

Immunochemistry of a formamide-extracted antigen from Clostridium perfringens cell walls.

The type-specific antigen of a strain of Clostridium perfringens involved in food poisoning was isolated from the cell wall by the use of hot formamide. The antigen appears to consist of polysaccharide or mucopeptide. The formamide extract was shown to be heterogeneous by gel filtration on Sephadex G-200. The serologically active fraction contained about 25% of the amount of protein present in the original formamide extract. Hexosamine, acetyl groups, and carbohydrate also were detected. The formamide extract showed a high degree of serological activity. The serological activity was increased twofold on Sephadex gel filtration.

Alkynes↗