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T Nishimura

Publications and source records attributed to T Nishimura.

At least 1,495 records · Page 83Linked to original sources
PubMed1981

Progesterone-induced smooth muscle-like cells in the subperitoneal nodules produced by estrogen. Experimental approach to leiomyomatosis peritonealis disseminata.

In order to examine the pathogenesis and histogenesis of leiomyomatosis peritonealis disseminata (LPD), guinea pigs were treated with various doses of estradiol benzoate (E) (40, 80, 100, and 200 microgram/day, three times a week, by intramuscular injection). After treatment for 3 months, each dose of E produced lesions simulating the disseminated pattern of LPD. Ultrastructurally, the nodules were considered to be composed of cells resembling those of fibroblast. In guinea pigs, pretreatment with estradiol benzoate (100 microgram/day, three times a week intramuscularly for 3 months followed by combination treatment with E and progesterone (P) (0.5 and 1.0 mg/day, once a week, intramuscularly) for 1 to 3 months produced nodules similar to those with estrogen alone. Ultrastructurally, these nodules were composed of cells resembling smooth muscle and decidual cells. According to these results, we conjectured that estrogen differentiates and proliferates cells with the features of fibroblast-like cells from the subcoelomic totipotential mesenchyme, and these cells are differentiated into smooth muscle-like cells and decidua-like cells under the influence of both estrogen and progesterone, resulting in the production of multiple subperitoneal nodules.

Abdominal Neoplasms↗
PubMed1981

Echocardiographic features of the false tendons in the left ventricle.

M mode and two dimensional echocardiographic features consistent with previously reported autopsy findings of false tendons were seen in 5 of approximately 1,000 consecutive echocardiographic examinations. Later, the presence of false tendon was proved at autopsy in one of the five cases. Examination in three cases revealed heart disease: aortic regurgitation, third degree atrioventricular (A-V) block with aortic regurgitation and invasive thymoma with pericardial effusion; examination in two cases revealed no heart disease. In three cases, M mode echocardiograms revealed in the outflow tract of the left ventricle abnormal linear echoes that strongly mimicked those in other disorders such as discrete subaortic stenosis or flail aortic valve. In two cases, there were abnormal linear echoes in the left ventricle toward the apex. In three cases, two dimensional echocardiograms revealed long-string-like echoes stretching from the upper part of the interventricular septum across the ventricular cavity to the lateral wall of the left ventricle in long and short axis views or in four chamber views. In two cases, long slender echoes between the lower parts of the interventricular septum and the left ventricle were seen in apical long axis views. These string-like echoes seem to represent the false tendons previously reported at autopsy, although actual pathologic confirmation was available in only one of the five cases. It is concluded that (1) M mode and two dimensional echocardiograms can demonstrate the presence of false tendons, (2) two dimensional echocardiograms are useful in differentiating false tendons from other conditions causing abnormal linear echoes in the outflow tract of the left ventricle on M mode echography.

Adult↗
PubMed1981

A new method for preparation of pure zonae pellucidae in large quantities from porcine ovaries.

A new method for preparation of large quantities of zona substance in pure form from porcine ovaries has been described. In addition to the previously reported techniques of glass wool treatment and sieving by saran meshes, the following three significant improvements have been introduced: disruption of ovaries by an electric machine equipped with two multi-needed disks, which resulted in a considerably accelerated recovery of follicular oocytes with a high yield; low-speed centrifugation at 170 X g for 15 s was found to be an obligatory step to eliminate light particulate material from the crude oocyte suspension; use of 50% sucrose solution in discontinuous density gradient centrifugation permitted complete separation of homogeneous samples at two stages of the final preparation of zona-encased oocytes or of oocyte-free zonae. Microscopic examination revealed no contaminating components in the zona preparation. With this method 93 mg of lyophilized zona preparation were obtained from 24 553 porcine ovaries. Analysis of a solubilized zona substance by Sephacryl S-200 column chromatography showed the presence of two major glycoproteins which could not be separated completely from each other. By analysis of the two components with SDS-PAGE, only a single, but broad, band of glycoprotein was found, indicating the successful isolation of a major component(s) from porcine zonae.

Animals↗
PubMed1981

Noninvasive assessment of T-wave abnormalities on precordial electrocardiograms in middle-aged professional bicyclists.

Six middle-aged, active, professional bicyclists with T-wave abnormalities on precordial ECGs were studied noninvasively. Twenty-five aged-matched bicyclists without T-wave abnormalities served as the control subjects. Increased voltage of SV1 + RV5 was demonstrated in all subjects. A 5-year follow-up study revealed that these abnormalities of T-wave inversion became more pronounced with age, except in one case. VCGs showed enlargement of anterior QRS loop and discordant T loop, in all cases. On echocardiography, thickness of both the interventricular septum and the left ventricular posterior wall, and left ventricular mass were significantly increased compared with the control group. 201Tl myocardial scintigraphy at rest and during exercise revealed no regional perfusion defects of the tracer in either case. We conclude that: (1) T-wave abnormalities of precordial ECGs in six middle-aged athletes were progressive in nature; and (2) these electrocardiographic abnormalities seem to be related to left ventricular hypertrophy induced by steady and strenuous training rather than to coronary artery disease.

Adult↗
PubMed1981

Characterization of hydrolase H, a new muscle protease possessing aminoendopeptidase activity.

A newly-identified protease from rabbit skeletal muscle, named hydrolase H [Okitani, A. et al. (1980) Agric. Biol. Chem. 44, 1705-1708] has been shown to hydrolyze L-leucine beta-naphthylamide as well as alpha-N-benzoyl-DL-arginine beta-naphthylamide. The enzyme hydrolyzes protamine in the manner of an endopeptidase and hydrolyzes tripeptides and tetrapeptides in the manner of an aminopeptidase. Thus it has been concluded that the enzyme possesses the properties of both endopeptidase and aminopeptidase and that it should be classified as an aminoendopeptidase. Both activities of endopeptidase and aminopeptidase are maximal at pH 7.5-8.0 and enhanced remarkably by thiol compounds. Both activities are stable at pH 7-9 and protected by 2-mercaptoethanol. They are inhibited by monoiodoacetic acid, leupeptin, Zn2+ and Ni2+, but not affected by EDTA, trypsin inhibitor, pepstatin, antipain and phenylmethylsulfonyl fluoride. These results suggest that the enzyme is a thiol protease. The enzyme is composed of three kinds of subunits, the chain Mr of which are 51000, 72000 and 92000.

Aminopeptidases↗
PubMed1981

Lysyl oxidase activity in the mouse uterine cervix is physiologically regulated by estrogen.

Lysyl oxidase activity in the mouse cervix was examined during the estrous cycle, pregnancy, and the postpartum period. It was highest in estrus and lowest in diestrus. On day 1 of pregnancy, the activity was comparable to that seen in estrus. It then declined continuously until day 17 of pregnancy, when it was approximately equal to that seen during diestrus. The activity showed a slight increase toward term, then a precipitous increase occurred on the first postpartum day. The activity fell by the seventh postpartum day to a value comparable to that seen in diestrus. Enzyme activity fell to one fourth of its former value 3 days after ovariectomy. The injection of 1 microgram 17 beta-estradiol or more in 0.9% NaCl 10 days after ovariectomy raised the activity, in 18 h, to the level seen in estrus. One milligram of progesterone had no effect on the enzyme activity, but a combination of 1 microgram 17 beta-estradiol and 1 mg progesterone raised the activity to that seen with 1 microgram 17 beta-estradiol alone. These results suggest that lysyl oxidase activity in the mouse cervix is under the control of estrogen.

Amino Acid Oxidoreductases↗
PubMed1981

Functional and structural relationships in steroidogenesis in vitro by human corpora lutea during development and regression.

To investigate the steroidogenic function of human corpora lutea, during the menstrual cycle, slices of seven corpora lutea obtained at various stages in the luteal phase were incubated with [1-14C]acetate; four of them were incubated with [4-14C]pregnenolone simultaneously. Incorporation or conversion of 14C radioactivity into progestins, androgens, and estrogens was assessed by a reverse dilution technique with recrystallization to constant specific activity. Distinct differences in function and morphology were observed before and after the completion of corpus luteum formation. In developing corpora lutea, 1) a marked increase in progesterone formation from [14C]acetate, 2) a transient increase in androgen formation, including dehydroepiandrosterone, with a concomitant decrease in estrogen formation from the two precursors, and 3) degeneration, followed by disappearance of thecal cells, were observed. In mature and regressing corpora lutea, 1) a drastic decrease in progesterone formation from [14C]acetate, 2) an increase in estrogen in contrast to a decrease in androgen formation from the two precursors, 3) a clear differentiation of theca lutein cells, and 4) a more relatively pronounced transformation of pregnenolone to estrogen in regressing than in mature corpora lutea were found. We conclude that marked qualitative and quantitative changes in steroidogenic function are closely related to structural changes during corpus luteal development and regression.

Acetates↗
PubMed1981

Heteroimmunization with isolated human ova.

Rabbit antiserum raised against isolated human ova produced an intense immunofluorescence and a precipitate on the outer surface of human and porcine zonae pellucidae. The antiserum reacted with none of 22 human tissues nor with any of 4 body fluid components by immunofluorescence or immunodiffusion analysis, but the antiserum agglutinated AB erythrocytes after absorption with O erythrocytes. The anti-zona activity was achieved by higher titres for human than for porcine zonae. Immunofluorescence on porcine zonae was completely abolished by absorption with porcine ova, whereas a weak but definite fluorescence remained on human zonae. These findings indicate that the human zona pellucida consists of at least three distinct components; (1) a specific antigen(s) shared by human and porcine zonae, (2) an antigen(s) specific to human zonae, and (3) a non-specific antigen(s) associated with the blood group substances.

Adult↗
PubMed1981

Effects of prednisolone and anti-macrophage serum on the development of carditis and arthritis due to group A hemolytic streptococci in mice.

The effects of prednisolone and anti-macrophage serum (AMS) on the development of cardiac and articular lesions were compared in experimentally infected mice with group A hemolytic streptococci. The predonine-treated mice had a higher mortality rate and greater abscess formation than in the AMS-treated mice. The predonine-treated group had a higher incidence of cardiac lesions due to chronic pericarditis and chronic myocarditis, and the former was particularly frequent. Pathologic findings seen in the AMS-treated mice were those of acute pancarditis. The AMS-treated animals also had lesions of subacute or chronic arthritis, whereas articular lesions encountered in the Predonine-administered group were frequently those of chronic periarthritis and, in no instance, synovitis. These data indicated that treatment with AMS is more effective than that with prednisolone to experimentally induced rheumatic fever in laboratory animals.

Animals↗
PubMed1981

Modeling of digestive tract lesions using silicone rubber RTV (KE-12).

In order to produce life-size models of digestive tract lesions, we applied silicone rubber RTV (KE-12) over the surface of the resected fresh, half-fixed or completely-fixed specimens to achieve their impressions. Into these impressions, super-hard plaster, acrylics and lysine base were separately poured, with the resultant casts realizing faithful replicas of the original patterns, finely reproducing their mucosal micro-structures. A photofluorogram of the silicone rubber pattern taken by using softex could reveal roentgenographic micromucosal features on a single plane. Clinically, endoscopic casting of lesions in similar procedures could produce their models, providing data available for estimation of the size and depth of an ulcer. Our method would be of help in dynamical pursuit of digestive tract lesions, as well as for comparison of the vital realities of lesions and their histopathological findings. The method may further contribute to reducing the dosage of x-ray bombardment in gastric fluoroscopy.

Animals↗
PubMed1981

Endoscopic gastric polypectomy using high frequency current: its significance for total biopsy of gastric polyp.

Endoscopic polypectomy using high frequency current was performed for 281 out of 345 gastric polyps (230 cases), while the remaining 64 small polyps were cauterized. Histopathologic examinations carried out in 274 out of the 281 polypectomized polyps confirmed gastritis polyposa in 41 lesions, hyperplastic polyps in 216 including 3 cases of neoplasm, atypical epithelium in 4, submucosal tumor in 2, and polypoid cancer in 1. This procedure of endoscopic polypectomy has proved to enable histologic examination of a polyp as a whole, and to allow a highly risk-free endoscopic treatment of polyps. In the currently observed 216 hyperplastic polyps, 3(1.4%) were found to have neoplastic changes.

Endoscopy↗