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T Matsuya

Publications and source records attributed to T Matsuya.

At least 91 records · Page 5Linked to original sources
PubMed1988

Growth inhibition and differentiation of human salivary adenocarcinoma cells by medium conditioned with normal human fibroblasts.

The present study demonstrates that normal human fibroblasts (WI-38) exert a profound influence on the growth and differentiation of HSGc-C5, a clonal neoplastic epithelial cell line of human salivary gland origin. Coculture of HSGc-C5 with WI-38 resulted in a slowing of growth and an increase in glycosaminoglycan synthesis by an indirect effect involving a diffusible factor(s). Conditioned medium (CM) from WI-38 grown in Dulbecco's modified Eagle's medium supplemented with 10% fetal bovine serum affected HSGc-C5 as follows. The CM suppressed growth of monolayer cells; inhibited DNA synthesis; suppressed growth (decrease in size of colonies) in semisolid agar; stimulated glycosaminoglycan synthesis, induced expression of functional markers of the salivary gland, such as the secretory component, lactoferrin, and lysozyme; inhibited expression of alkaline phosphatase; and induced morphological alteration into elongated cells. These findings strongly suggest that WI-38 CM contains a factor(s) which inhibits growth and induces differentiation of HSGc-C5. The CM was also active on other human cancer cells as a growth inhibitor, but not on normal human fibroblasts. Partial purification and characterization of the factor(s) suggests that it may be a novel protein carrying both tumor inhibiting and differentiation inducing activities.

Adenocarcinoma↗
PubMed1988

Further characterization of bleomycin-resistant HeLa cells and analysis of resistance mechanism.

Bleomycin (BLM)-resistant HeLa cells (HeLa-BLMr), which have been subcultured for more than 150 passages during over 2 years in the presence of 1 micrograms/ml of BLM and stably possess a 20-fold-increased BLM-resistance in vitro, were further characterized. The nude mouse tumors produced by HeLa-BLMr were significantly less sensitive (P less than 0.005-0.01) to BLM administration than those produced by HeLa cells, and the cells primarily cultured from nude mouse tumors of HeLa-BLMr and transplanted serially 5 times in the absence of BLM also exhibited a similar degree of BLM resistance to that of HeLa-BLMr cultured in BLM-containing medium. The BLM-resistance mechanism of HeLa-BLMr was partially analyzed. The cells showed about 40% decreased accumulation and 2-3 times reduced retention of [3H]peplomycin, a novel BLM analog, as compared to HeLa cells, but the BLM-hydrolase activity was at almost the same level as that of HeLa cells when determined by HPLC. Furthermore, alkaline sucrose gradient analysis of cellular DNA after BLM treatment revealed that the damaged DNA was more efficiently repaired in HeLa-BLMr than in HeLa cells. These results suggest that decreased drug accumulation and retention, and elevated DNA repair activity are the main mechanism of BLM resistance in HeLa-BLMr.

Animals↗
PubMed1988

Abnormal cellular property of fibroblasts from congenital gingival fibromatosis.

Two strains of cultured cells were isolated and characterized from the gingiva of two siblings with congenital gingival fibromatosis. The growth rate of both fibroblast strains was slower than that of comparable cells obtained from the normal gingiva of control individuals. The amounts of substances, including collagen and glycosaminoglycans, biosynthesized by the diseased cells were much greater than those by the control cells from normal gingivae. Namely, 11.7-13.7% of the protein synthesized by diseased cells was collagen, whereas collagen accounted for only 6.1-8.5% of the total protein produced by normal cells. Moreover, the production of a large amount of extracellular substances by the diseased cells was confirmed by electron microscopic examination. These observations suggest that the fibromatosis tissues contain affected fibroblasts which have low growth activity but are active in the production of much greater amounts of collagen and other extracellular substances compared to normal fibroblasts.

Adolescent↗
PubMed1988

Stimulation of phospholipase A2 and vascular permeability by an extract of granuloma induced in the rat by carrageenin.

Isolation from carrageenin-induced granuloma of rat of factors affecting phospholipase A2 (PLase A2) activity was attempted. Excised granuloma was extracted with 2% phenol and denatured both at acidic and alkaline pH's in boiling water. The extract was adsorbed on charcoal and eluted in an alkaline milieu. Following gel chromatography of the eluate on Sephadex G-25, the effect of this fraction on PLase A2 prepared from rabbit peritoneal exudates was examined. Materials affecting PLase A2 activity were eluted slightly behind the peak of saccharides having an approximate molecular weight of 800. Activation of PLase A2 was most pronouncedly observed in the sample prepared from 5 days granuloma. Activating effect on PLase A2 was not observed with the sample prepared from control rat skin. The effect of fractions that contained PLase A2 activating components on vascular permeability was investigated by measuring the leakage of i.v. administered pontamine blue. Injection of the sample containing PLase A2-activating materials into mouse paw induced the increase of vascular permeability in a dose dependent manner. Maximal effect was observed also in the sample obtained 5 days after the injection of carrageenin. Thus, the activating components may be involved in the processes of inflammation.

Animals↗
PubMed1987

Coordination of the levator veli palatini and intrinsic laryngeal muscles: an evoked electromyographic study in the dog.

Fourteen dogs anesthetized with sodium pentobarbital were used as experimental animals in an electromyographic study of the functional relationships among the levator veli palatini and the intrinsic laryngeal muscles. The following results were obtained: A single pulse stimulation to the afferent fibers of the pharyngeal branches of the glossopharyngeal nerve evoked ipsilateral reflexes from the levator veli palatini and laryngeal adductor muscles. The laryngeal abductor muscle, however, did not respond to this stimulation. A repetitive pulse stimulation (3-5 Hz) to the afferent fibers of the pharyngeal branches of the glossopharyngeal nerve decreased the level of amplitude of the respiratory discharge from the laryngeal abductor muscle. The reflex discharges in the levator veli palatini muscle were decreased when the respiratory discharges in the laryngeal abductor muscle were enhanced. The present study indicates that there are relationships between the palatal and glottal movements and that the coordinate actions in these regions are influenced by two types of relationships among the palatal and laryngeal muscles. One is the relationship between the levator veli palatini and laryngeal adductor muscles, and the other is that between the levator veli palatini and laryngeal abductor muscle.

Afferent Pathways↗
PubMed1985

Cardiovascular risk factors in American and Japanese executives. Telecom Health Research Group.

A standardized cardiovascular risk factor examination was given to executives in the headquarters of the American Telephone and Telegraph Company and the Nippon Telegraph and Telephone Public Corporation. As expected from the national mortality data, evidence of ischaemic heart disease was more common among American than Japanese executives. The frequency of some but not all risk factors was consistent with the observed differences in ischaemic heart disease. Americans were fatter than their Japanese counterparts, obtained a higher proportion of their caloric intake from animal fats, had higher serum cholesterol levels, and more of them felt that their lives were highly stressful. On the other hand, Japanese executives were much more likely to be cigarette smokers and showed a greater increase in blood pressure with age. Serum high-density lipoprotein cholesterol levels and the ratio of saturated to unsaturated fatty acids in the serum were similar in the two groups.

Adult↗