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Biomedical subjects

H Kotani

Publications and source records attributed to H Kotani.

213 records · Page 12Linked to original sources
PubMed1977

Killer toxin for sake yeast: properties and effects of adenosine 5'-diphosphate and calcium ion on killing action.

The killer character of strain isolated from the main mash of sake brewing which produces a killer substance for sake yeast was transmitted to hybrids of the strain and a standard strain of Saccharomyces cerevisiae through a cytoplasmic determinant. The character was eliminated at 41 degrees C by incubation followed by growth at 30 degrees C. The killer strain produced the killer toxin in a growth-associated manner. A preparation of crude killer toxin extract showed first-order inactivation and a linear Arrhenius plot between 25 and 40 degrees C, with an activation of energy of 55.0 kcal/mol. Addition of 1% of synthetic polymer protected the toxin from inactivation by agitation but not by heat. Enhancement of the killer action toward sensitive yeast cells by only the nucleotide adenosine 5'-diphosphate (ADP) was observed after plating on agar medium as well as after incubation in liquid medium. The addition of CaCl2 reversed the enhancing effect of ADP on killing activity. This action of CaCl2 was inhibited by cycloheximide, suggesting that protein synthesis is required for recovery of toxin-induced cells in the presence of CaCl2. Further, CaCl2 overcame the decrease in the intracellular level of adenosine 5'-triphosphate (ATP) enhanced by ADP in killer-treated cells and also inhibited leakage of ATP from the cells with immediate response. The mode of killing action is discussed in terms of a transient state of the cells and the action of ADP and CaCl2.

Adenosine Diphosphate↗
PubMed1975

[Sterilization of diets and drinking water in the autoclave in the Laboratory Animal Center, Nippon Veterinary and Zootechnical College (author's transl)].

Efficiency of sterilization was shown to vary according to the type of autoclave, and this would be taken into consideration for preparing sterilized diet and water for laboratory animals. It seems necessary to sterilize diet and water for 60 and 150 minutes, respectively, at 120 degrees C using the autoclave in the Laboratory Animal Center of the Nippon Veterinary and Zootechnical Collge.

Animal Feed↗
PubMed1975

Antibiotic A-16316-C, a new water-soluble basic antibiotic.

A new water-soluble basic antibiotic named antibiotic A-16316-C was isolated together with antibiotic A-396-I and hygromycin B from a streptomyces strain identified as Streptoverticullium eurocidicus. The properties of the antibiotic A-16316-C were similar to those of destomycin B. But it was found that the antibiotic A-16316-C was not identical with destomycin B on the basis of NMR analysis. On acidic degradation antibiotic A-16136-C gave N, N'-dimethyl-2-deoxystreptamine, destomic acid and D-mannose. The gross structure for antibiotic A-16136-C was deduced from chemical reactions and spectral data.

Aminoglycosides↗
PubMedDate not supplied

Tissue-specific generation of two preprotachykinin mRNAs from one gene by alternative RNA splicing.

A novel mammalian neuropeptide, the tachykinin substance K, is specified by a discrete genomic segment. Alternative RNA splicing generates two distinct mRNAs encoding the neuropeptide substance P alone or with substance K from a single preprotachykinin gene. Relative amounts of the mRNAs vary in different tissues, suggesting that the substance K-encoding sequence is regulated in a tissue-specific manner.

Amino Acid Sequence↗
PubMedDate not supplied

Ureaplasma-eukaryotic cell interactions in vitro.

Ureaplasmas from six animal species were inoculated into cell cultures derived from human, simian and murine hosts. All ureaplasmas infected at least two of the cell cultures tested. Supplemental medium urea was not a requirement for cell culture infection, and Ureaplasma growth in cell cultures occurred in as little urea as 4 micrograms/ml, similar to findings in broth-propagated organisms. These findings are of potential significance due to an observation (HM Jernigan, Jr: Exp Eye Res 37:551, 1983) that certain tissues produce urea locally. This may explain why ureaplasmas can be isolated from tissues outside the urinary tract where large amounts of urea are not routinely encountered. Ureaplasmas generally increased from titers of approximately 10(2) to 10(4) to ones of 10(5) to 10(6), but occasionally 10(7), color changing-units/ml within 2 days. Apparently a cell culture product is required for Ureaplasma growth. In several systems, Ureaplasma infection persisted and Ureaplasma-infected cell cultures could be passaged.

Adsorption↗
PubMedDate not supplied

Cytologic detection of malignant lymphoma cells in urine and hydrocele fluid.

The cytologic finding of malignant lymphoma cells in the urine and hydrocele fluid of a 32-year-old man is reported. The tumor cells were scattered singly and were slightly larger than normal lymphocytes. Their nuclei were ovoid or irregular in shape. Hyperchromasia, coarsely distributed chromatin and prominent nucleoli were characteristic. Histologic examination showed a non-Hodgkin's malignant lymphoma, corresponding to the large-cell type of diffuse lymphoma.

Adult↗