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Biomedical subjects

E Suzuki

Publications and source records attributed to E Suzuki.

At least 415 records · Page 23Linked to original sources
PubMed1986

Intermediate filaments in alpha-keratins.

Previous x-ray diffraction studies on the alpha-keratins of hair and wool have revealed that the intermediate filaments (IF) have a helical structure rendered imperfect by a precisely defined dislocation. It has also been possible to deduce a surface lattice for the IF and to determine the number of IF molecules associated with each lattice point. In this work this information is combined with data on the ionic interactions between the coiled-coil rope segments of the IF molecules to provide a plausible model for the pattern of interactions that stabilize the framework of the IF in the "hard" alpha-keratins. Similar interaction studies of the proteins from the IF in the so-called "soft" alpha-keratin from the stratum corneum layer of the skin suggest that they are likely to have an essentially similar pattern.

Animals↗
PubMed1986

Serological surveys of Corynebacterium kutscheri infection in mice and rats.

Serological surveys of mice and rats naturally infected with Corynebacterium kutscheri were performed by examining serum samples collected from breeder and laboratory colonies between 1981 and 1983. Among 756 mice from 73 conventional colonies, only 4 animals (0.5%) from 3 colonies (4.1%) developed C. kutscheri antibody of 1:40 to 1:2, 560 titers. Three of them suffered from abscess caused by the organism. Regarding a titer of 1:40 or higher as reliably positive, 87 (13.0%) of 669 conventional rats or 20 (32.8%) of 61 colonies were found to be infected with the organism. The antibodies were detected in both types of animals older than 6 months of age. No lesions caused by C. kutscheri were found in almost all the rats examined. Germ-free and SPF mice and rats were all negative for antibody at 1:5 serum dilution.

Animals↗
PubMed1986

Effect of erythorbic acid administration on ascorbic acid content in guinea pig tissues.

The effect of erythorbic acid (ErA) on ascorbic acid (AsA) content in the tissues of normal and AsA-deficient guinea pigs was studied. The animals were sacrificed at varying intervals during the experimental period, and the liver, adrenal glands, spleen and kidneys were removed. The amounts of AsA and ErA in the tissues were measured by HPLC. The content of AsA in the tissues of the animals administered both AsA and ErA was lower than that of the animals administered only AsA. But the disappearance rate of AsA from the tissues of the AsA-deficient animals was similar to that of the animals administered only ErA. The amount of AsA in the tissues of the animals administered both AsA and ErA during the repletion period was lower than that of the animals administered only AsA. These results suggest that ErA administration may affect the amount of AsA in the tissues by inhibiting its tissue uptake or its storage in the tissues, and not by accerelating the catabolism of AsA in the tissues.

Adrenal Glands↗
PubMed1986

Effect of graded doses of erythorbic acid on ascorbic acid content of tissues of guinea pigs.

The effect of graded doses of erythorbic acid (ErA) on the content of ascorbic acid (AsA) in the tissues of guinea pigs administered AsA was studied. The guinea pigs were administered 5 mg AsA and 1, 5, 20, and 100 mg ErA; or 1 mg AsA and 1 and 20 mg ErA; or 20 mg AsA and 20 mg ErA for 16 days. The animals were then sacrificed, and the liver, adrenal glands, spleen, and kidneys were removed to determine the contents of AsA and ErA by using HPLC. The content of AsA in the tissues of the animals administered less than 5 mg ErA together with 5 mg AsA was not significantly different from that of the animals administered 5 mg AsA. The administration of 100 mg ErA together with 5 mg AsA caused a decrease in the amount of AsA in the tissues. The content of AsA in the tissues of the animals administered ErA together with 1 mg AsA was not significantly different from that of the animals administered 1 mg AsA. In the case of animals administered an equal amount of both AsA and ErA, the AsA tissue content was consistently much higher than that of ErA. These results indicated that the administration of relatively small amounts of ErA did not appear to reduce the availability of AsA.

Adrenal Glands↗
PubMed1986

A survey of Streptococcus pneumoniae, Streptococcus zooepidemicus, Salmonella spp., Bordetella bronchiseptica and Sendai virus in guinea pig colonies in Japan.

S. pneumoniae, S. zooepidemicus, Salmonella spp., B. bronchiseptica and Sendai virus were examined in a total of 45 guinea pig colonies (17 institutional and 28 breeder's colonies) of Hartley strain, and found to be positive in 6, 3, 5, 20 and 14 colonies, respectively. Sendai virus was highly prevalent among guinea pigs, showing so high rates positive as 80 to 100% of animals obtained from 11 of the 14 contaminated colonies. B. bronchiseptica was also shown to be prevalent within contaminated colonies by indication of rates positive more than 40% of animals examined in 14 of the 20 colonies. Infection rates of other 3 pathogens, however, ranged from lower than 20% to higher than 80% according to colonies. All strains of Salmonella isolated in this survey were identified as S. typhimurium and those of S. pneumoniae as serotype 19F.

Animals↗
PubMed1986

Metabolic fate of N-nitrodibutylamine in the rat.

The metabolic fate of N-nitrodibutylamine (NO2DBA) and N-nitrobutylamine (NO2BA) was investigated in the rat. Eight N-nitramines, including glucuronides, were isolated and identified from urine of rats given NO2DBA. They were produced by omega, omega-1, omega-2 and alpha oxidations of the N-nitramine. The in vivo metabolic pattern of NO2DBA was similar to that of N-nitrosodibutylamine, except that the monodealkylated metabolite NO2BA was also isolated and characterized. When NO2BA was administered to rats, no N-nitramine other than a small amount of unchanged NO2BA was identified in the urine. Besides N-nitramines, N-acetyl-S-(butyl, 3-oxobutyl and 3-hydroxybutyl)-L-cysteines were isolated and identified (as their methyl esters) from the urine of rats given both NO2DBA and NO2BA. The relative ratio of these three L-cysteine derivatives obtained from NO2DBA was quite similar to that from NO2BA, indicating that NO2DBA produces in vivo a chemical species with butylating ability through NO2BA.

Alkylating Agents↗
PubMed1985

Recognition by a natural cytotoxic antibody of lactoneotetraglycosyl ceramide as an antigenic molecule in a syngeneic rat fibrosarcoma.

Conventionally bred rats possess in their sera an NA which has a cytotoxic effect on a tumor cell line (KMT-17) derived from a fibrosarcoma induced by 3-methylcholanthrene and which can be absorbed by normal rat tissues. We have succeeded in purifying a glycosphingolipid as an antigen reactive to NA. GSLs isolated from the tumor cells were separated into neutral and acidic fractions. The former fraction was judged to be antigenic as detected by its capacity to absorb NA. The antigenic fraction was further separated into 7 fractions (Frs. A to G) by silicic acid chromatography. The antigenic activity was detected in only Frs.D and E, although Fr.D was a more potent antigen than Fr.E. Chemical and immunochemical analyses showed that both fractions are composed of lactoneotetraglycosyl ceramide (paragloboside), Gal(beta 1-4)GlcNAc(beta 1-3)Gal(beta 1-4)Glc(beta 1-1)ceramide, and that the more active GSL, Fr.D, contains larger amounts of long fatty-acid chains. Inhibition studies using disaccharides and monosaccharides indicated that a N-acetyllactosamine moiety, Gal(beta 1-4)GlcNAc, of the GSL is a specific site of NA. These results suggest that paragloboside is an NA antigen and that a sugar chain portion of this GSL is required for defining specificity while the ceramide portion plays a role in potentiating the antigenicity of this GSL antigen for NA.

Amino Sugars↗
PubMed1985

High-performance liquid chromatographic studies on non-mercapt in equilibrium with mercapt conversion of human serum albumin. II.

High-performance liquid chromatographic (HPLC) analysis of human serum albumin (HSA) on a GS-520 column with 0.03 M sodium phosphate buffer-0.15 M sodium sulphate (pH 6.87) showed three peaks, the principal component corresponding to human mercaptalbumin (HMA) and the secondary and tertiary components to nonmercaptalbumin (HNA). Using HPLC analysis, the nonmercapt----mercapt conversion of HSA during haemodialysis and the mercapt----nonmercapt conversion after haemodialysis in chronic renal failure were re-confirmed, indicating that HMA is a covalent carrier protein for sulphur-containing amino acids. Fractions of HMA in various liver diseases were significantly lower than those of healthy male adults.

Adult↗
PubMed1985

The structure of collagen.

A knowledge of the structure of collagen fibrils is important for any rational discussion of the occurrence and treatment of fibrosis. The different genetic types of collagen, and the structure of the triple-helical molecule as refined from X-ray fibre diffraction data, are described. The problem of determining molecular arrangement in native tissues is discussed. The various models proposed for the molecular arrangement of type I collagen are compared and an account is given of the quasi-hexagonal model. A detailed analysis of the X-ray diffraction patterns from native type I collagen fibres is used to provide a quantitative description of the quasi-hexagonal model. Parameters such as molecular positions, azimuthal orientation and axial shift can be estimated from the diffraction patterns. These parameters refer to the helix main-chain. Side-chain conformations can then be built in by molecular graphics and the predicted X-ray pattern for the complete model compared with the observed pattern.

Animals↗
PubMed1985

HPLC-studies on nonmercapt-mercapt conversion of human serum albumin.

Human mercaptalbumin (HMA) and nonmercaptalbumin (HNA) could be separated by high-performance liquid chromatography (HPLC) at neutral pH. Using HPLC, the present authors found the nonmercapt-mercapt conversion (HNA----HMA) during hemodialysis and the mercapt-nonmercapt conversion (HMA----HNA) after hemodialysis in chronic renal failure, indicating HMA as the covalent carrier protein for sulfur-containing amino acids.

Chromatography, High Pressure Liquid↗
PubMed1985

In vitro metabolism of N-nitrodialkylamines.

The in vitro metabolism of N-nitramines was investigated in order to compare it with that of N-nitrosamines and to elucidate the mode of mutagenic action. N-Nitrodibutylamine (NO2DBA) and N-nitrodiethylamine (NO2DEA) were incubated with liver microsomes and hepatocytes prepared from rats treated with phenobarbital, and the products were analyzed by high-performance liquid chromatography and gas-liquid chromatography. The in vitro metabolic pattern of these nitramines was similar to that of the corresponding nitrosamines, except that N-nitro-N-alkylamines (produced via alpha-hydroxylation) were identified after incubation of the nitrodialkylamines. In the case of NO2DBA, besides N-nitro-N-butylamine, several nitramines produced by omega, omega-1, and omega-2 oxidations were identified as metabolites. NO2DBA and NO2DEA were mutagenic to Escherichia coli WP2 hcr- but not to Salmonella typhimurium TA1535. They were mutagenic only in the presence of hepatic microsomes, whereas their metabolites, N-nitro-N-butylamine and N-nitro-N-ethylamine, were direct mutagens. Thus, N-nitrodialkylamines are also metabolically activated to mutagens through alpha-hydroxylation.

Aniline Compounds↗