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Biomedical subjects

H Taniguchi

Publications and source records attributed to H Taniguchi.

At least 739 records · Page 41Linked to original sources
PubMed1979

Interaction between NADPH-cytochrome P-450 reductase and cytochrome P-450 in the membrane of phosphatidylcholine vesicles.

Cytochrome P-450 and NADPH-cytochrome P-450 REDUctase, both purified from liver microsomes of phenobarbital-pretreated rabbits, have been incorporated into the membrane of phosphoaditylcholine vesicles by the cholate dialysis method. The reduction of cytochrome P-450 by NADPH in this system is biphasic, consisting of two first-order reactions. The rate constant of the fast phase, in which 80--90% of the total cytochrome is reduced, increases as the molar ratio of the reductase to the cytochrome is increased at a fixed ratio of the cytochrome to phosphatidylcholine, suggesting that the rate-limiting step of the fast phase is the interaction between the reductase and the cytochrome. The rate constant of the fast phase also increases when the amount of phosphatidylcholine, relative to those of the two proteins, is decreased. This latter observation suggests that the interaction between the two proteins is effected by their random collision caused by their lateral mobilities on the plane of the membrane of phosphatidylcholine vesicles. The rate constant of the slow phase as well as the fraction of cytochrome P-450 reducible in the slow phase, on the other hand, remains essentially constant even upon alteration in the ratio of the reductase to the cytochrome or in that of the two proteins to phosphatidylcholine. No satisfactory explanation is as yet available for the cause of the slow-phase reduction of cytochrome P-450. The overall activity of benzphetamine N-demethylation catalyzed by the reconstituted vesicles responds to changes in the composition of the sysTEM IN A SIMILAR WAY TO THE FAST-PHASE REDUCTION OF CYTOCHROME P-450, though the latter is not the rate-limiting step of the overall reaction.

Animals↗
PubMed1979

Gross and histological types of early gastric carcinomas in relation to the acid-secreting area.

The relation of gastric acid-secreting function to the gross and histological types and locations of carcinomas was examined in 53 patients with early gastric carcinomas. Studies were made by the endoscopic Congo red test developed in this clinic. Results indicated a close correlation between the gross and histological types of early gastric carcinoma and the extent of the acid-secreting area. In general, when the acid-secreting area was large, the carcinomas were ulcerated and histologically undifferentiated and they were chiefly located in nonacid-secreting areas adjacent to acid-secreting areas, or sometimes they were surrounded by acid-secreting areas. On the contrary, when there was little or no acid-secreting area the carcinomas were polyploid and histologically differentiated, and they were located in nonacid-secreting areas far from acid-secreting areas.

Adenocarcinoma↗
PubMed1979

Primary adenoid cystic carcinoma of the esophagus: report of a case.

A case of primary adenoid cystic carcinoma of the esophagus is reported. A 51-year-old male patient had a tumor in the lower third of the esophagus which was incidentally found during an examination for cholelithiasis, and resected successfully. The tumor exhibited a polypoid appearance covered by normal esophageal epithelium, localized entirely in the submucosal layer, and morphologically identical to adenoid cystic carcinoma in the salivary glands. The patient is still alive and well three and one-half years after surgery. This seems to be a typical case of adenoid cystic carcinoma of the esophagus arising from the submucosal esophageal gland.

Aged↗
PubMed1979

Relation of intestinal metaplasia to the acid-secreting area.

The distribution of intestinal metaplasia in relation to the acid-secreting are was investigated in 66 patients not suffering from gastroduodenal diseases. Studies were made via the endoscopic Congo Red test in combination with the methylene blue staining method. In this test, the acid-secreting area is identified as a "discolored" area in which Congo Red turns from red to blue-black, and areas of intestinal metaplasia were observed as areas staining blue with methylen blue. A close relationship was found between the acid-secreting area and the distribution of intestinal metaplasia; in general, intestinal metaplasia tended to be more extensive and more frequent when the acid-secreting area was small. It was also found that intestinal metaplasia increased with age. However, even in patients who were over 40 years of age, intestinal metaplasia was seen in 12.5% only, if the acid-secreting area was large. Hence, it appears likely that development of intestinal metaplasia is more closely related to the acid-secreting function than to aging.

Adult↗
PubMed1979

Mammary tumour incidence in relation to the pattern of oestrous cycles in mice.

The patterns of oestrous cycles were examined in new strains of mice exhibiting a high (SHN) and a low (SLN) mammary tumour incidence. These mice originated from the same stock of Swiss albino mice. At the age of 3-4 months, SHN mice showed much longer cycles with continual dioestrous periods than SLN mice. The average lengths of cycles and dioestrous periods were, respectively, 8.3 +/- 0.3 and 6.0 +/- 0.4 days in SHN mice and 4.6 +/- 0.1 and 2.5 +/- 0.1 days in SLN mice. Furthermore, the distinct alteration in the patterns of cycles from SHN to SLN type was associated with complete reduction in mammary tumour incidence in highly inbred C3H/He female mice maintained by brother X sister mating with no selection for mammary tumourigenesis. The relation between the pattern of oestrous cycles and mammary tumourigenesis is discussed from the viewpoint of the endogenous hormonal milieu and the responsiveness of target organs.

Animals↗
PubMed1979

High concentration of gamma-aminobutyric acid in pancreatic beta cells.

The gamma-aminobutyric acid (GABA) concentration of pancreatic islets in rats treated with streptozotocin (STZ) and of human insulinoma tissue was studied. Seven hours after the administration of 65 mg/kg body weight of STZ, a distinct increase in serum insulin concentration and at the same time a decrease in blood glucose level were seen. Twenty-four hours after the injection of STZ, however, the level of serum insulin decreased much, whereas that of blood glucose increased considerably. On the other hand, the GABA concentration of the islet was reduced dramatically to about one-tenth the control level after both 7 and 24 h. The histologic investigations of the islets revealed the destruction of B cells but no changes in A and D cells 7 and 24 h after the treatment of STZ. Nerve fibers and nerve endings in the islets were preserved intact all through the study. The GABA and insulin contents of the two cases of human insulinoma were determined. One insulinoma, which was compactly occupied with B cells according to its histologic features, contained a high concentration of GABA. The other tumor, having a rather sparse distribution of B cells in it as compared with the former case, possessed a lower concentration of GABA, but it was still high compared with that of its surrounding tissues. The present observations indicate that a large amount of GABA is available in the B cells of the pancreatic islets.

Adenoma, Islet Cell↗
PubMed1979

Evaluation of a commercial enzyme immunoassay for insulin in human serum, and its clinical application.

We applied a "sandwich" method, with use of beads coated with anti-insulin serum and of peroxidase-labeled anti-insulin serum, to an enzyme immunoassay of insulin in human serum. 5-Aminosalicylic acid was used as the substrate for the enzymic reaction. As little as 5 milli-int. units of insulin per liter of serum insulin was detectable. Reproducibility was satisfactory, but extraordinarily high concentrations of proinsulin and of hydrogen donors such as reduced glutathione affect results of the assay. Values determined by our enzyme immunoassay and by double-antibody radioimmunoassay correlated highly (r = 0.938, p less than 0.001, n = 216). We recommend this method for use in the clinical laboratory.

C-Peptide↗
PubMed1978

A cytologic study on small cell carcinoma of the esophagus.

The cytologic picture of small cell carcinoma primarily arising from the esophagus was studied with 7 cases which were confirmed by histologic examination. Cytomorphologic characteristics of small cell carcinoma of the esophagus are as follows: the arrangement of groups of tumor cells is irregular and overlapping with indistinct cell boundaries. The cytoplasm is small, or sometimes absent. The nuclei are round, oval or occasionally spindle shaped. Nuclear borders are thin. The chromatin of finely granular pattern has increased and is evenly distributed.

Aged↗
PubMed1978

Mechanisms of late recurrence after radical surgery for gastric carcinoma.

Factors involved in late recurrence of gastric carcinoma were investigated in 25 patients with late recurrence who died five or more years after radical surgery and 129 with early recurrence who died within two years after surgery. In the patients with late recurrence, the important routes of cancer spread in the initial phase of the recurrence were contiguous invasion and lymphatic spread. Whether early or late recurrence occurred had a high correlation with the following four conditions: (1) the amount of residual cancer left at the time of surgery; (2) the spread of the residual cancer; (3) the rate of cancer proliferation; and (4) the resistance of the host. To prevent late recurrence, it is necessary not to leave any cancer tissue in these routes at the time of gastrectomy, as well as to employ adjuvant chemo- and immunotherapy for the inhibition of cancer proliferation and elevation of the host resistance.

Humans↗
PubMed1978

Studies on angiopathy due to carbon disulfide. Retinopathy and index of exposure dosages.

The occurrences of retinopathy (microaneurysms/small dot hemorrhages) and the coded resting and postexercise ECG findings suggestive of coronary heart disease (CHD) were studied among 420 Japanese male workers exposed to carbon disulfide and 390 men not exposed to such a solvent. Retinopathy was detected in 24.4% of the exposed group and in 3.8% of the nonexposed group by color fundus photography. Among workers of the former group there was a significant correlation between retinopathy prevalences and the index of exposure dosages (r = 0.925, P less than 0.01). However, correlation between the prevalence of retinopathy and duration of exposure was not so high (r = 0.647, 0.10 less than P less than 0.25). The occurrences of coded resting and postexercise "coronary" ECG findings were not related to the index of exposure dosages. Some risk factors for CHD such as total serum cholesterol, triglycerides, beta-lipoproteins, blood pressure, obesity, and skinfold thickness were simultaneously studied. But these variables did not prove to be important in the development of angiopathy due to carbon disulfide, especially the so-called retinopathia sulfocarbonica.

Adult↗