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Biomedical subjects

R Saito

Publications and source records attributed to R Saito.

At least 361 records · Page 20Linked to original sources
PubMed1976

Fine structure of a diffuse undifferentiated small-cell carcinoma of the thyroid.

Differentiating diffuse undifferentiated small-cell carcinoma of the thyroid from malignant lymphoma is difficult. A case of small-cell carcinoma was studied by electron microscopy and is reported here to illustrate the value of electron microscopy in separating epithelial thyroid tumor from lymphoma. Ultrastructurally, the tumor was composed of cells possessing occasional intercellularjunctional complexes and spaces with microvilli. There were abundant free ribosomes and well-developed rough endoplasmic reticulum in the cytoplasm. Golgi apparatus, smooth endoplasmic reticulum, membrane-bound cytosomes, and centrioles were also evident. Numerous swollen mitochondria were seen in some tumor cells. A few large tumor cells characterized by abundant cytoplasm containing few mitochondria, endoplasmic reticulum and numerous microfibrils were also observed. A few collagen fibers, lymphocytes and plasma cells were present among tumor cells. No basement membranes nor virus-like particles were seen.

Adult↗
PubMed1976

Adjuvant effect of cord factor, a mycobacterial lipid.

Cord factor was a good adjuvant in mice and rats but exerted little if any adjuvant effect in guinea pigs. In rats, cord factor not only enhanced antibody production but also induced delayed hypersensitivity. Wax D was a weak adjuvant in mice. Cord factor caused a marked inflammatory swelling at the sites of injection in mice, but it caused no such swelling in rats and guinea pigs.

Adjuvants, Immunologic↗
PubMed1976

Tissue reaction to middle ear prostheses: in vivo observation (rabbit ear lobe) of polyethylene tube, stainless steel wire and absorbable gelatin sponge used in middle ear surgery.

Over the past ten years, polyethylene tube, stainless steel wire and absorbable gelatin sponge have come to be used in middle ear surgery. A modified Williams' steel chamber with a transparent central area was embedded in a rabbit ear lobe surgically, and cross-sectioned polyethylene tube, stainless steel wire or absorbable gelatin sponge were inserted respectively. The in vivo tissue reaction to each of these installed materials was observed daily microscopically. Finally, in the case of both the cross-sectioned polyethylene tube and the stainless steel wire, the chambers were fixed with 10% formalin solution and the contents stained for histological study. The results were as follows: Absorbable gelatin sponge was absorbed completely by phagocytosis in 62 days. Polyethylene tube was encapsulated by a layer of fibroblasts by day 110 in one case and by day 140 in another case; these findings were confirmed histologically on day 110 and 281. Almost all the surface of the stainless steel wire was encapsulated by a layer consisting of giant cells, on which a dense fibrous layer was superimposed by day 82. It is concluded that polyethylene tube, stainless steel wire, and absorbable gelatin sponge should be well tolerated in middle ear surgery.

Absorption↗
PubMed1975

Reduced response to phenobarbital by the liver of rats fed a choline-deficient diet.

1. The response of the liver to phenobarbital administration was compared in rats fed either laboratory chow, a semipurified choline-supplemented diet or a semipurified choline-deficient diet. 2. The liver contents of proteins, lipids and cytochrome P-450, as well as the activity of aminopyrine and ethylmorphine demethylases, were measured after 5 days of feeding and five daily injections of phenobarbital. Liver sections were examined electron microscopically. 3. In rats fed the choline-supplemented diet, phenobarbital administration caused increases in cellular constituents, enzyme activities and smooth endoplasmic reticulum membranes as great as those seen in rats fed laboratory chow. However, in rats fed the choline-deficient diet, the response of the liver to phenobarbital administration was severely reduced in comparison to that in rats fed the other diets. 4. It is concluded that dietary choline and an adequate synthesis of lecithins are necessary for the induction of microsomal mixed-function oxidases and the concomitant accumulation of smooth endoplasmic reticulum in hepatocytes.

Animals↗
PubMed1975

Cord factor not toxic in rats.

Systemic toxicity and local inflammatory activity of cord factor were compared between mice and rats. In mice, repeated intraperitoneal injection of cord factor caused a marked worsening of general condition and high mortality. The swelling of footpads injected with cord factor was also marked in mice. In contrast, injection of cord factor produced no such toxic reactions in rats, except that repeated intraperitoneal injections of high doses of cord factor induced an accumulation of ascites.

Animals↗
PubMed1975

Comparative studies of parasympatholytic drugs on stomach (double blind test) and analysis of relation between gastric form and tonus.

Effects of 3 kinds of parasympatholytic drugs (timepidiumbromide, hyoscine-N-butylbromide and prifinium-bromide) and placebo (physiological saline solution) on the gastrointestinal tract were evaluated roentgenographically by double blind technique in a total of 101 male human subjects. The results may briefly be summarized as follows: 1. There were significant differences on hypotonic rate being one of the indexes of the gastric tonus between timepidium-bromide and placebo. The effects of 3 experimental drugs were significantly high as compared with that of placebo on peristaltic movement of the stomach. The effect of timepidium-bromide was significantly different from that of placebo on the site of arrival of barium. 2. The comparison of degrees of the gastric tonus between main and control tests revealed that the effect of placebo obtained in the main test was significantly inferior to that of hyoscine-N-butylbromide obtained in the control test, whereas there existed no significant differences of the effects among 3 active drugs. 3. Effects of each drug on the gastric tonus which was scored by hypertonic, normotonic and hypotonic state were evaluated by stratification. The result showed that the effect of timepidium-bromide was significantly greater than that of placebo. 4. All active drugs were not significantly different in terms of 7 observed values each on the gastric form.

Adhesiveness↗