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K Hisatsune

Publications and source records attributed to K Hisatsune.

At least 91 records · Page 5Linked to original sources
PubMed1982

Occurrence of uronic acid in lipopolysaccharides of Vibrionaceae.

The occurrence of uronic acid as a sugar constituent of lipopolysaccharides (LPS) in Vibrionaceae was demonstrated for the first time. More than 100 strains were examined. Of five genera constituting Vibrionaceae, i.e., Vibrio, Aeromonas, Plesiomonas, Photobacterium, and Lucibacterium, the latter three contained uronic acid in LPS of all of their constituting members examined, while it was totally lacking in Aeromonas LPS so far tested. Only the members of genus Vibrio were found to be divided into uronic acid-containing and -lacking groups; V. parahaemolyticus, V. alginolyticus, V. fisheri, V. costicola, Beneckea ('Vibrio'), and V. fluvialis belonged to the former, while all four biotypes of V. cholerae regardless of their serotypes, V. vulnificus and V. anguillarum, belonged to the latter group. The uronic acid content of V. parahaemolyticus O1 to O12 LPS ranged from 1.6 to 4.2%. The uronic acid residue released from V. parahaemolyticus O1, O4, O10, and O12 LPS by heating in 5% acetic acid at 100 C for 2 hr was identified as galacturonic acid; in particular, that from O12 LPS was characterized as D-galacturonic acid.

Aeromonas↗
PubMed1981

A comparative study of the sugar composition of O-antigenic lipopolysaccharides isolated from Vibrio alginolyticus and Vibrio parahaemolyticus.

A comparative study of the sugar composition of O-antigenic lipopolysaccharides (LPS) isolated from Vibrio alginolyticus and those from V. parahaemolyticus was carried out. 3-Deoxy-D-mannooctulosonic acid, 2-keto-3-deoxy octonate (KDO), a regular sugar constituent of gram-negative bacterial LPS, was totally absent from LPS of all V. alginolyticus strains examined as it was from those of V. parahaemolyticus. Furthermore, a KDO-like thiobarbituric acid test-positive substance, identical with that of either V. parahaemolyticus 07 or 012, was also found in LPS from three strains, 505-78, 905-78, and 1013-79 (designated tentatively as group I), out of the five strains of V. alginolyticus tested. LPS from the members of group I contained, as component sugars, glucose, galactose, L-glycero-D-manno-heptose, glucosamine, galactosamine, the KDO-like substance, and an unidentified amino sugar P1. Thus, LPS of the members of group I possessed a similar sugar composition which is similar to that of LPS from either V. parahaemolyticus 97 or 012. LPS of strain 1027-79, one of the other two strains (designated tentatively as group II), contained as component sugars, glucose, L-glycero-D-mannoheptose, glucosamine, galactosamine, galactosamine, and the other unidentified amino sugar P2, while LPS of strain 53-79, the other member of group II, contained galactose as an additional component. The results indicate that LPS of strain 1027-79 has a sugar composition similar to that of V. parahaemolyticus 09 LPS.

Amino Sugars↗
PubMed1980

Lipopolysaccharides of R mutants isolated from Vibria cholerae.

The chemical and serological properties of lipopolysaccharides isolated from the S form and from the R form of cholera vibrios were compared. It was found that the S-R mutation of cholera vibrios involves total elimination of the two component amino sugars of S-form lipopolysaccharides, i.e. quinovosamine and perosamine. This elimination resulted in the loss of O-specificity of S-form lipopolysaccharides and concomitant appearance of strong serological cross-reactivity, in the passive-haemolysis-inhibition test, among R-form lipopolysaccharides regardless of the serotypes (Inaba and Ogawa) of their S parent strains.

Amino Sugars↗
PubMed1980

Sugar composition of O-antigenic lipopolysaccharides isolated from Vibrio parahaemolyticus.

Vibrio parahaemolyticus, a causative bacterium of food poisoning unique for its particular primary association with sea products, is now divided serologically into 11 or 12 O-forms based on agglutination and agglutinin-absorption tests. We determined the sugar composition of the somatic O-antigens, i.e., lipopolysaccharides (LPS), of representative strains of each O-form. Of particular interest is the absence of evidence for the presence of 2-keto-3-deoxy-octonic acid (KDO), a regular sugar component of gram-negative bacterial LPS, in any LPS examined, with the exception of 06. Furthermore, 07 and 012 LPS contained a KDO-like compound that is, however, not identical with KDO. Glucose, glucosamine, and L-glycero-D-mannoheptose were found as common sugar constituents. Three unidentified amino sugars, designated here as P1, P2, and P3, were found. Various combinations of each of these unidentified amino sugars, and of galactose, fucose, arabinose, D-glyucero-D-mannoheptose, galactosamine, KDO, and the KDO-like substance were detected in accordance with the O-form of LPS. On the basis of the sugar composition, LPS of the 12 O-forms of V. parahaemolyticus can be classified into nine chemotypes, because 03, 05, and 011 LPS belong to the same chemotype and 07 and 012 to another chemotype.

Antigens, Bacterial↗
PubMed1980

Age-hardening of dental Ag-Pd-Cu-Au alloys.

Age-hardening mechanisms of dental Ag-Pd-Cu-Au alloys were investigated by means of electron microscopic observations. Hardening was due to the precipitation of the L10 type CuPd-ordered platelet in the grain interior and to the discontinuous precipitation at the grain boundary. The characteristics of age-hardening curves were determined by rates of continuous and discontinuous precipitation.

Copper↗
PubMed1979

Correlation between the capacity of bacterial lipopolysaccharide to supress experimental allergic encephalomyelitis and its mitogenic activity for lymph node cells in guinea pigs.

Protection of guinea pigs from experimental allergic encephalomyelitis (EAE) was attempted using bacterial lipopolysaccharide (LPS) from 4 sources. The ability of these LPS to induce DNA synthesis in guinea pig lymph node (LN) cells in vitro was also investigated. It was found that there existed a good correlation between the capacity of LPS to suppress EAE and their degree of mitogenic activities for LN cells. LPS from Escherichia coli 0111:B4 (Ec-LPS), which was most effective in suppressing EAE and also best inducer of DNA synthesis in LN cells, enhanced the proliferation of cells forming antibody to myelin basic protein (BP) in the regional LN. These results, in addition to the previous report, suggested that at the inductive phase the proliferation of B lymphocytes or their products, antibodies to BP, could inhibit formation of T lymphocytes sensitized to BP, resulting in suppression of EAE. Lipid A but not PS fraction of Ec-LPS showed a protective activity against EAE and a mitogenic activity for LN cells although less so than whole LPS. In addition, Lipid A appeared to exert its mitogenic effect mainly on B rather than on T lymphocytes.

Animals↗
PubMed1979

[Isothermal ordering processes of equiatomic alloy CuPt (author's transl)].

Isothermal ordering processes of equiatomic alloy CuPt quenched from above the critical temperature were investigated by means of electrical resistivity measurements, X-ray diffraction and electron microscopic observations. The main results obtained are as follows; (1) two different orderings are recognized at above and below 560 degrees C. Each main reaction is an ordering process having the activation energies of 30.6 and 17.4 kcal/mol, respectively. (2) In the early stage of ordering at the temperature below 200 degrees C the growth of disperse order is recognized by the increment of electrical resistivity, and has an activation energy of 30.1 kcal/mol. (3) At the temperature between 300 degrees C and 560 degrees C, the process of ordering consists of three stages having an activation energy of 17.4, 23.6 and 65.3 kcal/mol, respectively. These correspond to the ordering processes by the migration and the annihilation of quenched-in excess vacancies, the annihilation of secondary defects and the diffusion of equilibrium vacancies, respectively. (4) At the temperature above 560 degrees C, the process of ordering consists of two stages. The bulk of the ordering is a homogenous ordering within the grain.

Copper↗
PubMed1979

[Order-hardening in equiatmic alloy CuPt (author's transl)].

The order-hardening and its modes of equiatomic alloy CuPt were investigated by means of hardness test, X-ray diffraction and optical microscopic observations. The important results obtained are as follows; (1) Two different modes of order-hardening are recognized, namely at the temperature ranges of 400 degrees C-550 degrees C and 600 degrees C-700 degrees C. (2) The activation energies for order-hardening at lower and higher temperatures are 19.3 and 31.1 kcal/mol, respectively. The former corresponds to the migration and the annihilation of quenched-in excess vacancies, the latter corresponding to the growth of ordered domain. (3) Heterogeneous ordering along the grain boundary at lower temperature and homogeneous ordering within the grain at higher temperature are the dominant reaction for hardening. But the ordering is achieved by the nucleation-and-growth process at all temperature.

Copper↗
PubMed1979

[A study of the ageing process in dental Ag-Pd-Cu-Au alloys by anisothermal annealing method (author's transl)].

The ageing processes in dental Ag-Pd-Cu-Au alloy were investigated by means of electrical resistivity measurements during anisothermal annealing. The main results obtained are as follows; (1) There are two obvious precipitation processes (stage I and stage II) during anisothermal annealing after quenching from above critical temperature. And the apparent difference in stage I attribute to solution treatment temperature. (2) Stage I occured at lower temperature, is one ageing process by the migration and annihilation of quenched-in excess vacancies. Another is stage II at higher temperature by the diffusion of equilibrium vacancies.

Copper↗