Search PubMed⌕ Search

Biomedical subjects

K Mitani

Publications and source records attributed to K Mitani.

At least 235 records · Page 13Linked to original sources

Amplification of N-myc in a rhabdomyosarcoma.

N-myc is a member of the myc oncogene family and has been thought to be specific to neurogenic cells, since it is amplified in some neuroblastomas, retinoblastomas and small-cell lung carcinomas with endocrine properties. Hybridization analyses of DNAs isolated from surgically removed tumors revealed that N-myc was amplified about 6-fold in one of the three embryonic rhabdomyosarcomas examined. The rhabdomyosarcoma containing the amplified N-myc had metastasized into bone marrow, which is preferentially involved in the metastasis of neuroblastomas but is usually not involved in the case of rhabdomyosarcomas. Since rhabdomyoblasts are derived from mesenchyme, this indicates that N-myc gene amplification is not restricted to neurogenic tumors.

Child↗

Characterization of depolarization induced by palytoxin and grayanotoxin-I in isolated cardiac tissues from dogs and guinea pigs.

The mode of depolarizing action of palytoxin (PTX) was compared with that of grayanotoxin-I (GTX-I) to examine the site of action of PTX in cardiac tissues isolated from dogs and guinea pigs: PTX at above 1 X 10(-10) mol/l depolarized the membrane of canine Purkinje fibres, canine and guinea-pig ventricular muscles regardless of stimulation. The PTX-induced depolarization was resistant to 1 X 10(-5) mol/l tetrodotoxin (TTX) but was attenuated by low Na medium. GTX-I at 1 X 10(-5) mol/l depolarized the membrane of ventricular muscles from dogs and guinea pigs only when they were stimulated. Although GTX-I caused depolarization in Purkinje fibres in both stimulated and rested conditions, the effect was greater in stimulated fibres. In the presence of GTX-I, ventricular muscles generated long-lasting action potentials as a response to stimuli. TTX antagonized the GTX-I-action. After treatment of PTX, GTX-I still induced the long-lasting action potential and TTX could antagonize it. Ouabain at 1 X 10(-6) or 3 X 10(-6) mol/l partially inhibited the PTX-induced depolarization in guinea-pig papillary muscles. The data suggest that the TTX-sensitive Na channel is intact after treatment with PTX and that PTX acts on a site different from the Na channel, possibly on the Na+, K+-ATPase in cardiac cells.

Acrylamides↗

VMA mass screening program of neuroblastoma for infants in Nagoya City, Japan.

In Nagoya City, Japan, VMA mass screening for detection of neuroblastoma has been performed since 1977. Filter paper strips wetted with urine are mailed to a central laboratory. Positive tests are followed up by more definitive testing. Of the 20,053 urine samples of 6-month-old infants tested, January 1977 to March 1983, five asymptomatic infants with neuroblastoma have been discovered. All have been treated and are alive as of January 1984.

Child, Preschool↗

In vitro susceptibility of Haemophilus somnus to 33 antimicrobial agents.

Minimal inhibitory concentrations of 33 antimicrobial agents for Haemophilus somnus were determined by the agar dilution method. The tested H. somnus strains were highly susceptible to penicillin G, ampicillin, colistin, and novobiocin. They were not susceptible to spiramicin and sulfadimethoxine, and streptomycin-resistant strains were found.

Anti-Bacterial Agents↗

A lymphoblastoid cell line with high phagocytic activity established from peripheral blood of a patient with chronic myelocytic leukemia in blast crisis.

A human hematopoietic cell line (K-23-M) was established from a patient with chronic myelocytic leukemia in blast crisis. Morphologically, the cultured cells were lymphoblastoid cells that produced IgA and were Epstein-Barr viral nuclear antigen positive. But they showed high phagocytic activity to glutaraldehyde-treated sheep red cells and had properties of a monocyte or macrophage that included surface Fc receptors, alpha-naphthyl butyrate esterase positivity blocked by NaF, migration in soft agar and the ability to attach to a glass surface. Lysozyme secretion was absent, and chromosomes were diploid and Ph1 negative. This cell line is unique in that it has strong phagocytic activity. Its existence shows that lymphoblastoid cell line may be a more important cell line for the study of human hematopoietic cells than previously has been believed.

Antigens, Viral↗

Effects of gamma-oryzanol on lipid metabolism in rats fed high-cholesterol diet.

The lipid contents of the plasma and liver and enzyme activities in the aorta were determined in rats given the following diets: Group I, normal diet (ND); Group II, high cholesterol diet (HCD, ND plus 1% cholesterol and 0.5% cholic acid); Group III, HCD plus 0.5% gamma-oryzanol; Group IV, HCD plus 2% gamma-oryzanol in the last days of the 4th, 8th and 12th week of the feeding period. Total cholesterol, low-density lipoprotein-cholesterol and very low-density lipoprotein-cholesterol in the plasma were significantly higher in rats in groups III and IV than in those in group II. High-density lipoprotein-cholesterol was increased in groups III and IV. There were no differences in the triglyceride or phospholipids concentrations in the plasma of rats in the four groups. The liver weight was higher in the HCD groups (groups II, III and IV) than in the ND group (group I). The cholesterol ester and triglyceride contents of the liver were higher in the HCD groups than in the ND group, and the increase was the least in group IV of the HCD groups. Changes in acid cholesterol esterase activity and acyl CoA: cholesterol acyltransferase activity in rat aorta homogenates to compensate for lipid deposition were greater in groups III and IV than in group II.

Animals↗

Long-term survival in a case of hepatocellular carcinoma.

A patient with an unresectable hepatocellular carcinoma (HCC) who survived without active treatment 3 years and 8 months after histological diagnosis is described. The size of the liver, which was already quite huge at the time of diagnosis, changed little during the entire clinical observation. However, 2 months before death, his condition deteriorated rapidly following gastrointestinal bleeding due to the direct invasion of the stomach by HCC. A critical reason for the unusually long-term survival of the patient may stem from the facts that a well-differentiated and bile-producing HCC was extent in most encapsulated-tumor tissues and that liver cirrhosis was not present.

Carcinoma, Hepatocellular↗

Cellular fatty acid composition of Haemophilus equigenitalis.

The cellular fatty acid composition of eight Haemophilus equigenitalis strains was determined by gas-liquid chromatography. All strains showed a grossly similar pattern characterized by large amounts of 18:1 and 16:0. The amounts of 16:1, 18:2, 18:0, 3-OH 14:0, 3-OH 16:0, and 3-OH 18:1 were relatively small.

Chromatography, Gas↗