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Biomedical subjects

E Kano

Publications and source records attributed to E Kano.

At least 55 records · Page 3Linked to original sources
PubMed1986

Device of anoxic chamber system and repair of potentially lethal damage of anoxic cells in vitro.

In order to study radiation responses of anoxic plateau phase cells in vitro, an air-tight anoxic chamber was devised in which Chinese hamster V-79 or Swiss mouse NIH3T3 cells were deoxygenated by replacing the air with saturatedly humidified N2 gas. The cells as adhered on the culture plate, which was contained in the anoxic chamber, were x-irradiated. The deoxygenated condition in the anoxic chamber was maintained as long as necessary. Oxygen enhancement ratio obtained by the anoxic chamber was about 2.6. Repair of potentially lethal damage of the anoxic plateau phase cells was observed to the same extent of that of the oxic cells.

Animals↗
PubMed1986

An in vitro and in vivo screening system for new hypoxic cell radiosensitizers using EMT6 cells.

An experimental tumor system consisting of single cells, spheroids, and solid tumors was developed using the EMT6/KU cell-line for evaluation of new hypoxic cell sensitizers. This paper describes the radiation dose-survival curves of the system and the effects of four sensitizers [misonidazole, Ro 03-8799, KB-11 (a sulfonyltetrazole derivative), and DNIE (a dinitroimidazole derivative)] in this system. Dose-survival curves of the spheroids varied significantly depending on the irradiation conditions, but it was found that the spheroids could model the solid tumors when they were irradiated in flat-bottomed flasks. These spheroids and solid tumors contained substantial fractions of hypoxic cells, and hence were suitable for testing hypoxic cell sensitizers. Misonidazole at a concentration of 1 mM or 1 mmol/kg showed a constant enhancement ratio (ER) of 1.55 in all of the systems. The ERs of the other three compounds for single cells, spheroids, and solid tumors were 2.1, 1.9, and 1.65, respectively, for Ro 03-8799 (1 mM or 1 mmol/kg); 2.6, 1.6, and 1.0, respectively, for KB-11 (0.5mM or 0.5 mmol/kg); 1.8, 1.2, and 1.1, respectively, for DNIE (0.5mM or 0.5 mmol/kg). These results indicated that the ER for spheroids is closer to the ER for solid tumors than is the ER for single cells in most cases. It was also suggested that an efficient sensitizer in vivo shows little or no difference between its ER for single cells and that for spheroids.

Animals↗
PubMed1986

[Inhibition of the development of thermotolerance by combined treatment with an anticancer drug or benzylidene glucopyranose with the hyperthermia].

Transitional thermotolerance develops during (at below circa 43 degrees C) or after (at above circa 43 degrees C) hyperthermic treatment, increases through the first 6 h, is maintained for circa 24 h and disappears at circa 72 h after the hyperthermia. Therefore, a once every three days modality of hyperthermic treatment is preferred among the clinical institutions where therapeutic hyperthermia is provided. In the present communication, the inhibition of thermotolerance development by combined treatment of anticancer drug or benzylidene glucopyranose with hyperthermia and its related problems are reported.

Animals↗
PubMed1985

[A review of experimental thermochemotherapy in cultured cells].

Recent studies and reports on interactions of heat and drugs are somewhat scattered both in the temperatures and types of drugs adopted. In the present review, the current skate of knowledge regarding experimental thermochemotherapy and thermotolerance and heat shock proteins was evaluated. Hyperthermia is not only interesting as an adjuvant therapy but is also expected to be developed as an independent modality among oncotherapies available at present.

Animals↗
PubMed1985

Damage in DNA irradiated with 1.2 MHz ultrasound and its effect on template activity of DNA for RNA synthesis.

When aqueous DNA solution was irradiated with 1.2 MHz continuous ultrasound in the presence of cysteamine, the number of ultrasound-induced double-strand breaks of DNA was not influenced, but the number of ultrasound-induced single-strand breaks of DNA was reduced to about one-fifth that of the irradiated control. When the effect of cysteamine on the template activity of the ultrasound-irradiated DNA was investigated, the cysteamine was found to exert a leveling effect on the linear decrease of the template activity against ultrasonic intensity. Since cysteamine was known as an effective radical scavenger, the results of the experiment were regarded to suggest that (1) the double-strand breaks were exclusively induced by the mechanical effect of ultrasound, (2) the majority of single-strand breaks were produced by water radicals arising from cavitation, (3) the initial part in the decrease of the template activity was due to the double-strand breaks arising from mechanical effect, and (4) the further decrease of the template activity depended mainly on the single-strand breaks arising from water radicals.

Cysteamine↗
PubMed1983

Skin responses to step-up and step-down heating in C3H mice.

The effects of step-up (42 leads to 44 degrees C sequence) and step-down (44 leads to 42 degrees C sequence) heating were studied on the skin of C3H/He mouse feet. Skin damage in mouse feet exposed to 44 degrees C alone became proportionally more severe with increasing exposure time, while it was slight or not observed at 42 degrees C for up to 2 hr. Preheating to 42 degrees C for 60 or 120 min (step-up) had little effect on the damage from 30-60 min exposure at 44 degrees C, but increased the damage seen with 90 min at 44 degrees C. However, skin damage was markedly enhanced by exposure to step-down heating. On the other hand, thermal resistance was induced in the mouse skin by 44 degrees C fractionated treatments. The induced thermal resistance reached a maximum with a 1 day interval, and then disappeared after a 3 day interval. In another fractionation schedule of step-down heating, the enhanced skin damage which was observed when here was no interval, recovered rapidly and attained an additive response within a 1 day interval. No thermal resistance was observed.

Animals↗
PubMed1982

Cytotoxicity of methylmercuric chloride attenuated by serum proteins and it's release from the treated cells in vitro.

Knowledges on the characteristics in toxicity of methylmercuric chloride (MMC), obtained in the present series of experiments in vitro, would be summarized as follows: (1) No appreciable cell-phase-specific age-response to MMC through the cell cycle of JTC-11 line of cells in vitro was shown. Cytolethal sensitivity of the mitotic cells to MMC was equal to that of the exponentially growing cells. (2) Culture media were prepared in graded concentrations of serum proteins and the various albumin/globulin ratios. Cytolethal toxicity of MMC in the graded treatment periods and concentrations was assayed in the prepared media. The apparent MMC toxicity was decreased both by albumin and by globulin. The both serum proteins appeared to be cytoprotective from MMC toxicity. In culture medium containing albumin, or inactivated bovine whole serum, the cytolethal toxicity of MMC was not observed in the MMC treatment concentrations below 0.5 micrograms/ml, but it was observed for any MMC treatment periods in the any concentrations above 0.5 micrograms/ml. Increases in the concentrations of either albumin or globulin, or the both, correlated with the decrease of MMC toxicity. (3) MMC uptake to the given number of cells was measured and decreased MMC uptake of cells in the medium containing serum protein, compared with that in the serum-protein-free medium, was obtained. Rapid transfer of MMC from the cells to the MMC free medium was observed during the first 30 min after the MMC treatment, which was followed by a slower exponential regression of MMC content of the cells during the successive incubation in the MMC free growth medium.

Blood Proteins↗
PubMed1981

Highly sensitive sandwich enzyme immunoassay of human IgE with beta-D-galactosidase from Escherichia coli.

A highly sensitive sandwich enzyme immunoassay of human IgE was developed. Polystyrene balls were coated with goat anti-human IgE immunoglobulin (IgG) by physical adsorption. Goat anti-human IgE Fab' was purified by affinity chromatography and conjugated with beta-D-galactosidase from Escherichia coli. Using thus prepared anti-IgE-coated polystyrene balls and anti-IgE-beta-D-galactosidase conjugate, 0.2 mU (2 amol)--1 U of IgE per assay could be determined. When 0.1 microliter of serum per assay was used, the range of IgE levels in serum that could be determined was 2--10000 U/ml, and even 0.01 U/ml was measurable by using 20 microliters of serum. The regression equation and coefficient for correlation to radioimmunoassay were gamma (RIA) = 0.94 chi (EIA) + 18.2 and 0.96 (n = 81), respectively. The coefficients of within- and between-assay variations ranged from 5.4 to 8.5%. The mean levels of serum IgE determined by the present assay were 103 U/ml in 70 normal children and 1064 U/ml in 38 children with bronchial asthma.

Antibody Specificity↗