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Structural characterization of a novel glycoinositolphospholipid from the parasitic nematode, Ascaris suum.

A novel glycosphingolipid containing inositol phosphate as an acidic group has been demonstrated in whole tissues of the porcine roundworm, Ascaris suum. The thin layer chromatographic pattern of the total acidic glycolipid revealed the presence of several components, of which a major component (named AGL) with positive reactions toward both orcinol-sulfuric acid (sugar) and molybdate (phosphate) spray reagents was isolated and purified by the use of successive column chromatography on DEAE-Sephadex and silicic acid (latrobeads). From structural studies including compositional sugar analysis, hydrogen fluoride degradation, methylation analysis, periodate oxidation, proton magnetic resonance spectroscopy and fast atom bombardment mass spectrometry, the structure of AGL was deduced to be Gal alpha 1-2Ins(1-->)-P-Cer. Aliphatic constituents were lignoceric acid and its 2-hydroxy homologue as the principal fatty acids, and octadecasphinganine and branched heptadecasphinganine as the major sphingoids.

Animals↗

The structure of the repeating oligosaccharide unit of the pneumococcal capsular polysaccharide type 18C.

The structure of the repeating oligosaccharide of the pneumococcal capsular polysaccharide type 18C has been investigated. The repeating oligosaccharide, isolated from an aqueous hydrofluoric acid hydrolyzate of the polysaccharide, was shown, by fast atom bombardment-mass spectrometry, to have a molecular weight of 928, and to contain an O-acetyl group and a glycerol residue. Information about the sequence in the per-O-methylated oligosaccharide was derived from electron-impact mass spectrometry. Supporting data were obtained from methylation analysis, periodate and chromium trioxide oxidations, and enzymic and acid hydrolyses of the oligosaccharide. These studies indicated that the polysaccharide consists of the following pentasaccharide repeating unit. (formula see text)

Oligosaccharides↗

Structure of the serotype f polysaccharide antigen of Streptococcus mutans.

The structure of the serotype f polysaccharide antigen of Streptococcus mutans was determined by methylation analysis, periodate oxidation, and partial methanolysis, and the configuration of the anomeric linkages by 13C-n.m.r. spectroscopy, indicating the trisaccharide repeating unit----3)-alpha-L-Rhap-(1----2)-[alpha-D-Glcp-(1----3)]-alpha-L-+ ++Rhap- (1----. The structure of the backbone of the polysaccharide was confirmed by demonstrating immunological identity between the product of Smith degradation of the S. mutans serotype f antigen and the group A-variant streptococcal polysaccharide.

Carbohydrate Conformation↗

Structure of the type-specific polysaccharide antigen of Streptococcus rattus.

The structure of the type-specific polysaccharide antigen of Streptococcus rattus was determined by methylation analysis, periodate oxidation, and by 2D-1H- and 13C-n.m.r.-spectroscopy. The polysaccharide was found to possess the trisaccharide repeating unit----3)-alpha-L-Rhap-(1----2)-[alpha-D-Galp-(1----3)]-alpha-L-+ ++Rhap- (1----.

Carbohydrate Sequence↗

Structure of an extracellular polysaccharide produced by Erwinia chrysanthemi.

Erwinia chrysanthemi pv zeae strain SR260, a phytopathogen of corn, produced from lactose an acidic extracellular polysaccharide which was purified and found to consist of L-rhamnose, D-mannose, D-glucose, and D-glucuronic acid in the ratio of 3:1:1:1. A combination of chemical (carboxyl-group reduction, methylation analysis, periodate oxidation, Smith degradation, and lithium-ethylenediamine degradation) and physical (1 and 2D NMR spectroscopy) methods revealed that the polysaccharide is composed of a hexasaccharide repeating unit 1: [formula: see text]

Carbohydrate Conformation↗

Structure of the O56 antigen of Escherichia coli, a polysaccharide containing 7-substituted alpha-N-acetylneuraminic acid.

The O56 polysaccharide moiety of the O56 antigen (LPS) consists of D-glucose, D-galactose, 2-acetamido-2-deoxy-D-glucose, and N-acetylneuraminic acid in the molar ratios 1:1:1:1. Methylation analysis, periodate oxidation, mild acid hydrolysis, as well as 1H and 13C NMR spectroscopy showed that the O56 polysaccharide has the primary structure [formula: see text]

Carbohydrate Conformation↗

The defective dorsal discs gene of Drosophila is required for the growth of specific imaginal discs.

The wild-type allele of the gene defective dorsal discs (ddd) is required for the normal development of the dorsal thoracic discs in Drosophila melanogaster. In ddd mutant larvae the dorsal discs (wing, haltere, and humeral) are greatly reduced in size or absent while the ventral discs (leg) are unaffected. We have examined the function of the ddd+ gene in wing development. The ddd+ product is not involved in the initial determination of wing cells but rather is required for their subsequent proliferation during the larval period. Analysis of chimaeras shows that there is a requirement for ddd+ gene expression in wing discs, but it is sufficient for normal development that only some cells in a disc express the gene. We propose that the ddd+ product is involved in the synthesis of a factor which is required for the normal growth of wing discs and which can be transferred between wing disc cells.

Alleles↗

Analog delay line artifact rejector for evoked potential studies.

A true artifact rejector which utilizes a bucketbrigade delay line is described. The delay line enables scanning of all the data in the analysis period prior to its inclusion in the average. The device is small in size, independent of the averager, and the total cost of components is under $100. This artifact rejector is compatible with any averager. Artifact rejection can be according to excessive amplitude, as described in this version, or according to externally applied signals. In addition, by a minor change in the interference detector module, rejection could be according to other criteria, such as frequency contents. The utility of the device is demonstrated on records of auditory brain stem evoked potentials.

Analog-Digital Conversion↗

Spectral analysis of fetal heart rhythm in relation to fetal regular mouthing.

Fetal heart rate variation during fetal regular mouthing in behavioural state 1F was investigated applying spectral analysis. Periods with and without fetal regular mouthing movements were compared. The power spectrum of the periods with regular mouthing movements showed a peak at the frequency of the clusters of mouthing movements which was absent in the power spectrum of the corresponding periods without movements. The oscillations in the fetal heart rate associated with this peak in the power spectrum were detectable both in the heart rate tracings obtained from the abdominal electrocardiogram and those recorded by means of wide range Doppler ultrasound.

Electrocardiography↗

Causes of death in Japanese diabetics. A 20-year study of death certificates.

Death certificates filed between 1960 and 1979 in Osaka, Japan were analyzed to study causes of death in diabetic patients. It was observed that diseases of the circulatory system increased continuously from 15.2% in 1960-1964 to 27.2% in 1975-1979. Cerebrovascular disease and disease of heart were the leading causes of death throughout the study period. The rate of increase was much faster for disease of heart than for cerebrovascular disease, and there was only a small difference between them as cause of death in diabetic patients at the end of the observation period. Malignant neoplasms, cirrhosis of the liver, and pneumonia and bronchitis increased, whereas tuberculosis decreased sharply according to age-adjusted mortality rate during the 20-year period. Analysis based on O/E ratios suggested higher risk of dying from ischemic heart disease, tuberculosis and cirrhosis of the liver in Japanese diabetics than in the general population in this country.

Aged↗

The negative influence of delayed renal allograft function on longer-term graft survival in a pediatric population.

The influence of delayed graft function on renal allograft survival has been studied in a review of 322 renal transplants performed at one pediatric institution. The appearance of the first radionuclide renal scan was used to indicate early function in patients receiving their first cadaveric allograft. Patients whose first radionuclide renal scan showed both good renal perfusion and good function (n = 52) were compared with those whose scans demonstrated good perfusion but no function (n = 32). the actuarial graft survival of those with no function was significantly worse (P < .05). The difference in graft survival was not solely due to grafts lost in the early posttransplant period. Analysis of serial serum creatinine estimations suggests a process of continued inexorable nephron loss in some patients whose grafts showed a delay in achieving function.

Adolescent↗

A comparative tissue toxicity evaluation of established and newer root canal sealers.

Grossman's sealer, eucapercha, Endo-Fill, CRCS, Sealapex, Hypocal, and sterile saline solution (0.3 ml of each) were injected into specific dorsal subdermal tissue sites of 12 guinea pigs. The animals were killed after 6 days, 15 days, and 80 days (four per time period). Analysis of tissue response showed that, overall, Sealapex and Endo-Fill had less severe inflammatory reactions than any of the other test materials. Grossman's sealer, CRCS, and Hypocal showed principally severe inflammatory responses at both 6 and 15 days, but mild reactions at 80 days. Overall, eucapercha showed less severe inflammatory responses than Grossman's sealer, CRCS, and Hypocal. Diffuse calcification was induced by the three calcium hydroxide preparations (CRCS, Sealapex, and Hypocal). Eucapercha and Endo-Fill had minute local areas of calcification. Both Grossman's sealer and CRCS did not have overall favorable histologic reactions; however, Grossman's sealer and CRCS have been used successfully clinically. Further clinical studies are needed.

Animals↗

Respiratory behavior in groups of deaf and non-deaf GFF male mice.

Carbon dioxide emission (VCO2) of groups of 10 GFF mice, genetically deaf and non-deaf, were compared, in controlled conditions of temperature 20-21 degrees C, humidity 50-80% and light (LD12:12; L = 108 lux). A circadian rhythm of VCO2 was evidenced in both genotypes, with levels in D and in L significantly (0.001 less than p less than 0.01) greater in deaf than in non-deaf mice. Photic VCO2 variations were significantly (0.001 less than p less than 0.05) smaller at L----D and D----L in the deaf than in non-deaf genotype. Ultradian (tau greater than 20 minutes) rhythms were evidenced in both genotypes; Fourier periodic analysis showed several significant (0.001 less than p less than 0.05) differences between these 2 genotypes concerning mainly amplitudes, whilst spectral analysis showed slight frequency differences between them. Survival to an acute nitrogen hypoxia or to an acute carbon monoxide intoxication which was significantly (p less than 0.001 and p less than 0.05) lower in deaf than in non-deaf individuals confirms the differences in respiratory behavior of groups of these two strains of mice.

Acoustic Stimulation↗

The development of ciliated and mucus cells from basal cells in hamster tracheal epithelial cell cultures.

Hamster tracheal epithelia consist of three cell types: ciliated, mucus and basal cells. Autoradiographic data from several studies suggest that either basal or non-ciliated columnar cells may serve as stem cells for regeneration of lost or damaged ciliated and mucus cells. The objective of the present study was to examine the role of basal cells in the formation of ciliated and mucus cells in hamster tracheal epithelial (HTE) cell cultures via tritiated thymidine ([3H]-TdR) autoradiography. When 3 day cultures were pulsed with [3H]-TdR for 6 hr and incubated for 2 additional days in non-radioactive media (5 day total) label was present in the nuclei of basal and columnar epithelial cells suggesting that the labeled columnar cells may be derived from basal cells. However, the morphological reorganization occurring during this 2 day interval may create difficulties in this interpretation. Since these morphological changes are minimal during the 6 day to 8 day in vitro period, 6 day HTE cultures were pulsed with [3H]-TdR for 6 hr and incubated for 2 additional days in non-radioactive media (8 day total), and examined to further study the fate of labeled basal cells during this period. Analysis of these 8 day cultures revealed that labeled nuclei were present in both basal cells and adjacent ciliated and mucus cells. These results do not exclude the possibility of non-basal cell origin of ciliated and mucus cells in other systems but suggest that, at least in HTE cultures, undifferentiated basal cells have the ability to develop into ciliated and mucus cells.

Animals↗

Inhibition of brain choline acetyltransferase in vivo: (E)-1-methyl-4-(1-naphthylvinyl)-1,2,3,6-tetrahydropyridine hydrochloride (B115), a depot form of a potent inhibitor.

The quaternary ammonium salt (E)-4-(1-naphthylvinyl)pyridine hydroxyethyl bromide (B111) and the tertiary amine salt (E)-1-methyl-4-(1-naphthylvinyl)-1,2,3,6-tetrahydropyridine hydrochloride (B115), both previously shown to protect against organophosphate (OP) toxicity, were examined in vivo for effects on rat brain choline acetyltransferase (CAT) activity and acetylcholine (ACh) levels. When administered iv, but not when given ip, B111 was able to inhibit brain CAT 29% and reduce brain ACh levels 25%, yet was unable to prevent soman-induced increases in ACh. B115, which may serve as a depot form of a quaternary ammonium analogue, was able to decrease CAT activity as much as 80% upon multiple ip administration. This CAT inhibitory potency was unprecedented for a tertiary amine salt of its structure. However, ACh levels were reduced by no more than 25% and B115 was ineffective in preventing soman- and sarin-induced increases in ACh. Since the degree of inhibition of CAT activity produced by B111 and B115 was not accompanied by a corresponding decrease in ACh levels, the protection afforded by these compounds against OP toxicity is most likely not related to CAT inhibition. B115 was also tested for its ability to affect cholinergic receptor binding. B115 was administered to rats ip, twice daily, at low doses throughout a 3-week period. Analysis of cortex tissue revealed a 45% increase in nicotinic receptor binding with no change in either total muscarinic receptor binding (M-1 and M-2) or high-affinity muscarinic receptor binding (M-2 alone).

Acetylcholine↗

Characterization of the serotype e polysaccharide antigen of Streptococcus mutans.

The structure of the Streptococcus mutans serotype e polysaccharide was studied in order to determine the chemical basis of the immunological cross-reactions observed between it and the streptococcal group E polysaccharide. The chemical structure was established using methylation analysis, periodate oxidation, partial methanolysis and 13C NMR spectroscopy. The polysaccharide was found to consist of a polyrhamnose backbone of alternating 2- and 3-linked alpha-L-rhamnose units and sidechain beta-D-glucosyl units linked to the 2-position of rhamnose units in the backbone. This structure of the oligosaccharide repeating unit of the S. mutans serotype e polysaccharide was identical to that of the group-specific polysaccharide of group E Streptococcus. Possible explanations for the previously reported differences in these two polysaccharides are discussed.

Chemical Phenomena↗

Recurrent lymphocytic meningitis associated with hereditary isolated IgG subclass 3 deficiency.

We report the case of an otherwise healthy young adult woman who has suffered three episodes of lymphocytic meningitis of possible enteroviral aetiology during a 5 year period. Analysis of immunoglobulin subclasses has revealed a sustained reduction of IgG3 to below the fifth percentile. In addition, the patient's father and brother have a similar degree of IgG3 deficiency. Isolated IgG3 deficiency has previously been described in association with recurrent upper respiratory tract infections, asthma, obstructive lung disease and enteral infections. However, our patient did not have any of these and there was no other identifiable immune defect to account for the recurrent meningitis. Although a mere chance association is possible, the case is interesting as antibody responses involving IgG3 tend to be triggered by protein antigens such as viral envelopes, while humoral immunity is known to be important in the clearance of enteroviral infection.

Adolescent↗