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Biomedical subjects

M Kohno

Publications and source records attributed to M Kohno.

At least 541 records · Page 30Linked to original sources
PubMed1983

Cytostatic action of human fibroblast interferon in direct growth inhibition: effect on human malignant melanoma.

The mode of action of the direct antiproliferative effect of human fibroblast interferon (HuIFN-beta) on tumor cells was analyzed in vitro with a human malignant melanoma cell line, HMV-1. HuIFN-beta inhibited the growth of HMV-1 cells in a time-dependent fashion (50%-inhibition concentration: less than 50 IU/ml). Its action was cytostatic. DNA synthesis was inhibited before the antitumor effect appeared, and apparent dose-dependent inhibitions of RNA and protein synthesis were induced. An increase of cell protein content was seen with the occurrence of growth inhibition. Increase of cell volume and prolongation of doubling time were seen from the second day after the addition, which corresponded well with the effects of HuIFN-beta on the cell cycle (the accumulation of cells in the S phase). These results indicate that the direct antitumor effect of HuIFN-beta on HMV-1 cells may result from cell cycle retardation mediated through obstruction of DNA synthesis.

Cell Cycle↗
PubMed1982

Combination antitumor therapy with lentinan and bacterial lipopolysaccharide against murine tumors.

The antitumor effects of lentinan and bacterial lipopolysaccharide (LPS) were studied. Combined treatment with lentinan and LPS was very effective against Ehrlich carcinoma in ddY mice, and the syngeneic mammary carcinoma MM46 in C3H/He mice. Studies on the effective doses and times of administration showed that a single injection of lentinan plus LPS 12 days after subcutaneous inoculation of these tumors caused complete regression in 60 approximately 90% of the animals; complete regression of MM46 carcinoma was seen in 83% of the animals.

Animals↗
PubMed1982

Comparative studies on immunological properties of antitumor polysaccharide TC-13.

The biological and immunological characteristics of TC-13, an antitumor protein-bound polysaccharide, were studied. TC-13 had no direct cytocidal effect on Ehrlich carcinoma, but it induced antitumor resistance in mice whose tumors were regressed by TC-13. TC-13 changed the electrophoretic pattern of serum proteins of mice after its ip administration, causing a slow increase of the LB component and a rapid increase of the X component. TC-13 augmented the delayed-type hypersensitivity reaction to tumor homogenate, anti-SRBC antibody formation and the cytocidal activity of macrophages in an antibody-dependent system, but it had little or no effect on blast formation of spleen lymphocytes or carbon clearance. These results and comparative studies with other immunomodulators suggest that TC-13 is a unique polysaccharide having properties intermediate between those of lentinan, a simple-structured homologous polysaccharide from basidiomycetes, and lipopolysaccharide, a cell-surface component from bacteria.

Animals↗
PubMed1982

Antitumor effect of polysaccharide TC-13 on allogeneic and syngeneic tumors in mice.

The antitumor activity of TC-13, a protein-bound polysaccharide extracted from a rare actinomycetes was tested on allogeneic and syngeneic tumors in mice. In the allogeneic Ehrlich carcinoma system, TC-13 showed antitumor activity over a broad optimal dose range, when administered by various routes such as ip, iv, sc, it (intratumorally) or po, even when given before tumor inoculation. TC-13 showed synergistic antitumor effects in combination with other immunomodulators, e.g., lipopolysaccharide, lentinan and picibanil. It showed antitumor activity against syngeneic tumors, MM46 mammary carcinoma and MCS-8 and Meth A fibrosarcoma.

Animals↗
PubMed1982

Effects of human fibroblast interferon on human tumors transplanted into nude mice: sensitivity of human tumors to interferon.

The antitumor effect of human fibroblast interferon (HuIFN-beta) was examined using a nude mouse-human tumor xenograft group. Eight subcutaneously transplanted tumors--one line each of ovarian carcinoma, laryngeal carcinoma, carcinoma of the nasopharynx and hepatoma, and two lines each of lung carcinoma and melanoma--were used. HuIFN-beta at 1 X 10(5) IU/mouse was injected subcutaneously around the tumor or into the tumor itself. In the former case, statistically significant growth-suppressive effects were observed in one lung carcinoma (PC-12) and both melanomas (AM-1 and SK-14), but no effect was seen on the other five tumors. Further studies were made to ascertain the effects of intratumoral injections. Increased growth inhibition was observed in both melanomas (AM-1 and SK-14), but not in lung cancer (PC-12). Complete regression was seen in 3 of 8 mice carrying SK-14. The sensitivity of tumors to HuIFN-beta was correlated to the inhibitory effect of HuIFN-beta on cell division detected by histological observation.

Animals↗
PubMed1981

An automatic voltage adjuster for a single microelectrode recording of the membrane potential and resistance.

An automatic voltage adjuster was designed in order to apply an intracellular rectangular pulse of current and record the membrane potential simultaneously using a single intracellular microelectrode. The original voltage record consists of a rectangular signal signal (Va) due to the resistance of the microelectrode and a slowly rising signal (Vb) which is the proper value of the membrane potential shift produced by the application of the intracellular rectangular pulse of current. The instrument described in this paper samples the original signal (Va + Vb) at 0.5 approximately 1.0 ms after the application of the rectangular pulse of current, holds this voltage level (Va) and subtracts it from the original signal (Va + Vb) to obtain (Vb).

Animals↗