Search PubMed⌕ Search

Biomedical subjects

K Hamana

Publications and source records attributed to K Hamana.

77 records · Page 5Linked to original sources
PubMed1968

Factors affecting infection of protoplasts with deoxyribonucleic acid of actinophage PK-66.

To establish a method for transmission of genetic materials in the genus Streptomyces, the conditions of infection of protoplasts of S. kanamyceticus by actinophage PK-66 deoxyribonucleic acid (DNA) were studied. The protoplasts of Streptomyces were prepared by treatments with lysozyme and trypsin. The infectivity of the phage DNA was enhanced by the presence of NaCl in the medium. The optimal concentration of the protoplasts for infection with DNA was 7 x 10(7) to 4 x 10(8)/ml. A proportional relationship was found between the infectivity and the DNA concentration within a certain range. The maximal production of mature phage was achieved after 19 hr of incubation. The number of phage propagated in the infection mixture reached 10(4) plaque-forming units per ml under the appropriate conditions. The phage DNA infected not only protoplasts prepared from S. kanamyceticus but also those prepared from S. violaceoniger and S. acidomyceticus, which were resistant to intact phage PK-66.

Bacteriophages↗
PubMedDate not supplied

Elevation of acetylpolyamine levels in mouse tissues, serum and urine after treatment with radical-producing drugs and lipopolysaccharide.

Polyamines and acetylpolyamines were analyzed in the liver, spleen, lung, kidney, serum and urine by high-performance liquid chromatography on a column of cation-exchange resin after administering various cytotoxic substances to male mice. All of the compounds tested more or less affected the tissue levels of polyamines, including putrescine, spermidine, spermine and acetylpolyamines (N1-acetylspermidine and N1-acetylspermine). It was found that they were classified into two groups of substances: one group (including radical-producing drugs and lipopolysaccharide) which elevated the tissue levels of N1-acetylspermidine, especially in the liver, while another group of drugs (such as D-galactosamine and DL-ethionine) had little effect on the acetylpolyamine levels. When the acetylpolyamine levels rose, the levels of spermidine and spermine declined, and then putrescine levels were elevated. N1-Acetylspermine was detected only when N1-acetylspermidine levels were very high after treatment with radical-producing drugs and lipopolysaccharide. Halogenated carbon, such as carbon tetrachloride and halothane, elevated the levels of acetylpolyamines especially in the liver, while paraquat elevated them in all tissues examined.

Acetaminophen↗