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Biomedical subjects

H Sugihara

Publications and source records attributed to H Sugihara.

At least 325 records · Page 18Linked to original sources
PubMed1990

[Assessment of transient dilation of the left ventricular cavity in patients with hypertrophic cardiomyopathy by exercise thallium-201 scintigraphy].

Exercise Tl scintigraphy (EX-Tl) provides a noninvasive means of identifying myocardial perfusion abnormalities in patients (pts) with hypertrophic cardiomyopathy (HCM). We have noted that some pts with HCM have a pattern of transient dilation of the left ventricle (LV) on the immediate post exercise images as compared with 3 hour redistribution images. We presumed that left ventricular dilation was caused by subendocardial hypoperfusion. So we studied transient dilation of the LV in 50 pts with HCM and 20 controls (C). Initial and delayed conventional short tomographic images were obtained after reconstruction of 30 projections acquired over 180 degrees. Thirty six radii every 10 degrees were generated from the center of the middle myocardial images of the short axis. An area surrounded by the thirty six points of maximal count on each radius was calculated in initial and delayed images. Transient Dilation Index (TDI) as an index of dilation was determined by dividing an area in initial image by an area in delayed image. TDI in pts with HCM was larger than that in C. Pts with HCM were classified into the two groups, Group A: TDI greater than 1.11 (mean + 2 SD in C), 24 pts, Group B: TDI greater than 1.11, 26 pts. Frequency of pts with history of chest pain in Group A was higher than that in Group B, and frequency of pts with positive exercise ECG in Group A was higher than that in Group B. End diastolic volume in Group B did not change 10 minutes after exercise by radionuclide ventriculography. In conclusion, transient dilation of the LV in pts with HCM by EX-Tl is in appearance, and may reflect subendocardial ischemia.

Adult↗
PubMed1990

[Utility of reinjection method in stress Tl-201 myocardial scintigraphy to assess viability of the infarcted myocardium].

To assess viability of the infarcted myocardium, we performed stress Tl-201 myocardial scintigraphy using reinjection method in 37 patients with old myocardial infarction, and in 13 patients of them, Tl myocardial imagings were performed in resting state on the other day within 4 weeks after this examination. In this method, 111 MBq (3 mCi) of thallium was injected at the peak of exercise and initial and delayed images were acquired, then additionally 37 MBq (1 mCi) of thallium was injected after delayed scanning (reinjection) and we obtained post-reinjection images. Delayed images showed redistribution in 15 patients (41%), and no redistribution in 22 patients (59%). In post-reinjection images, 7 (19%) of 15 patients with redistribution and 3 (8%) of 22 patients without redistribution showed improvement of thallium uptake, in total 10 patients (27%) had additional thallium uptake in infarcted regions. And the degree of thallium uptake in post-reinjection images were almost equal to that in resting images. In conclusion, myocardial imaging using thallium reinjection method may be useful for the assessment of viability of the infarcted myocardium.

Female↗
PubMed1989

Localization of Drosophila neurons that contain choline acetyltransferase messenger RNA: an in situ hybridization study.

In situ hybridization with radiolabeled complementary RNA (cRNA) probes was used to determine the location of the messenger RNA (mRNA) encoding choline acetyltransferase (ChAT) in Drosophila nervous system. Areas in the cell-rich cortical regions of the cerebrum and optic lobes hybridized with substantial concentrations of the probe. This contrasted with the cell-sparse neuropil areas where no significant concentrations of probe were observed. Although most of the cortical regions were substantially labeled, there were regions within all of the areas where labeling was sparse or nonexistent. For example in the lamina, even though the monopolar cell layer appeared to be heavily labeled, there were some neuronal profiles that were not associated with the probe. Moreover, the epithelial glia that form an arch of cell profiles subjacent to the monopolar cells were not labeled, nor were amacrine neurons in the apex of the lamina near the external optic chiasma. The highest concentration of probe (approximately 140 grains/400 microns2) was observed in the laminar monopolar cell region and the cerebral cortical rind. The next most heavily labeled region (approximately 90 grains/400 microns2) occurred over cortical cells of the medulla-lobula. In the peripheral nervous system, label over the antennal sensory neurons amounted to about 75 grains/400 microns2, and the retinular cell layer of the compound eye exhibited about 60 grains/400 microns2. The control probe did not hybridize in significant quantities in either cellular or noncellular regions. This study presents evidence that large numbers of Drosophila cortical and primary sensory neurons contain the messenger RNA necessary for the production of ChAT, the acetylcholine-synthesizing enzyme. Further, our findings provide baseline information for use in ontogenetic studies of cholinergic neurons in Drosophila, and they also provide normative data for studying the effects of mutant alleles at the Cha or Ace loci upon the transcription of ChAT messenger RNA.

Animals↗
PubMed1989

Distribution of fibronectin and laminin in early and advanced signet-ring-cell carcinomas of the stomach.

An immunoperoxidase method was used to compare the distribution of fibronectin and laminin between superficially spreading and deeply infiltrating parts of signet-ring-cell carcinoma of the stomach. In both parts, laminin-containing basement membranes were generally scarce, but they were observed on some of the cancer cells which had differentiated to glandular cells. Intramucosal invasion fronts of superficially spreading cancers often showed a layered structure, consisting of a middle zone of small cancer cells together with a superficial and a deep zone of signet-ring cells. In this structure, linear fibronectin and laminin deposits were common on the cancer cells in the deep zone, but rare in the superficial zone. However, fibrillar fibronectin deposits in the stroma were not considerably larger in either zone. At extramucosal invasion fronts of deeply infiltrating (advanced) cancers, a stromal remodelling with an increased amount of fibrillar fibronectin deposits was often observed around the cancer cells, whose cell surface fibronectin was largely lost even from some basement membranes. These findings suggest that invasive activity of signet-ring-cell carcinoma may not be related to the mere presence or absence of cell-surface fibronectin and laminin but to the amount of stromal fibronectin, which could reflect a cell-stroma interaction. Signet-ring-cell carcinomas have a stage of intramucosal growth in which cancer cells may live in dependence upon the pre-existing stroma and form the layered structure, while in advanced stages cancer cells seemed to have acquired an ability to elicit their own "tumor stroma".

Adenocarcinoma, Mucinous↗
PubMed1989

Significance of cardiovascular malformations in cystic hygroma: a new interpretation of the pathogenesis.

Fetuses with cystic hygroma or loose skin of the neck were studied chromosomally and phenotypically to clarify the relation between neck abnormality and cardiovascular malformations. Of 12 fetuses, 9 had chromosome abnormalities: 4 with 45,X, 3 with trisomy 21, one each with trisomy 13, dup 6q. One had normal chromosomes. Two cases, in which chromosome analysis was unsuccessful, were morphologically suspected to be trisomy 13. Nine of the 12 fetuses had either bilateral cystic hygroma of the neck (7 cases) or nuchal bleb (2 cases: trisomy 13 and dup 6q). Two of the 3 remaining cases (trisomy 21) had loose skin of the neck, and one had edematous swelling of the skin of the neck. Except for the last case of trisomy 21, 11 fetuses (91.7%) had severe and/or rare cardiovascular malformations. They were divided into 3 major groups: a) spectrum of hypoplastic left heart syndrome (45,X and dup 6q), b) double outlet right ventricle, agenesis of semilunar valve (trisomy 13), and c) abnormality of atrioventricular orifice or valves (trisomy 21). One fetus with normal chromosomes had persistent left superior vena cava instead of absent right one and calcification of myocardium. Histological observation of edematous skin demonstrated the abnormal distribution of lymph vessels, including their absence. Some cases showed hypoplastic thymus. To integrate the findings of the present study and the descriptions in the literature, a pathogenesis is hypothesized in relation to migration of neural crest cells and extracellular matrix.

Abnormalities, Multiple↗
PubMed1989

Characterization of kallikrein-like enzyme from Crotalus ruber ruber (red rattlesnake) venom.

1. A kallikrein-like enzyme from the venom of Crotalus ruber ruber (red rattlesnake) had been isolated and characterized by Mori and Sugihara. The enzyme was active upon the kallikrein substrates, Pro-Phe-Arg-MCA and z-Phe-Arg-MCA, and slightly hydrolyzed Boc-Val-Leu-Lys-MCA, and Boc-Phe-Ser-Arg-MCA. 2. Unlike thrombin, the newly isolated kallikrein-like enzyme did not cause formation of a fibrin clot when fibrinogen was mixed with the enzyme. 3. The B beta chain of fibrinogen was first split and A alpha chain was cleaved later. Pancreatic kallikrein hydrolyzed only the A alpha chain without affecting the B beta chain. 4. The kallikrein-like enzyme produced kallidin (Lys-bradykinin) by splitting the Met-Lys bond instead of producing bradykinin. 5. The kallikrein analog JSI-450 (Ac-Phe-Ser-Pro-Phe-Arg-Ser-Val-Gln-Val-Ser-NH2) was also cleaved at the site of the Arg-Ser bond. 6. Its NH2-terminal amino acid sequence (Val-Ile-Gly-Gly-Asp-Glu-Cys-Asn-Ile-Asn-Glu-Arg-Pro-Phe-Leu-Val-Ala-Leu-Tyr- Asp-Ser-) is homologous to the rat pancreatic kallikrein and other snake venom proteases.

Amino Acid Sequence↗
PubMed1989

Two toxins from the venom of Trimeresurus tokarensis.

1. Two toxins, Tokaratoxin-1 (TT-1) and Tokaratoxin-2 (TT-2), were isolated from the venom of Trimeresurus tokarensis using gel filtration on a Sephadex G-100 column, followed by chromatography on DEAE-Sephacel and carboxymethyl-cellulose. TT-1 possessed both hemorrhagic and proteolytic activities. However, TT-2 did not show hemorrhagic activity. 2. Homogeneity was established by the formation of a single band in acrylamide gel electrophoresis, isoelectric focusing and SDS-PAGE. 3. Molecular weights of TT-1 and TT-2 were 71,000 and 25,400, respectively. Although TT-2 is a basic protein, TT-1 is an acidic protein. 4. Biological activities of TT-1 and TT-2 were inhibited by EDTA, EGTA and o-phenanthroline, suggesting that the toxins are metalloproteins. Atomic absorption analyses indicated that TT-1 contains 2.79 mol Ca/mol protein and TT-2 contains 1.04 mol Ca/mol protein and 1.07 mol Zn/mol protein, respectively. 5. The two toxins degraded the A alpha and B beta chains of fibrinogen. 6. TT-1 induced necrosis in addition to its hemorrhagic activity while TT-2 induced necrosis only.

Amino Acid Sequence↗
PubMed1989

Hemorrhagic toxin from the venom of Agkistrodon bilineatus (common cantil).

1. Hemorrhagic toxin was isolated from Agkistrodon bilineatus (Common cantil) venom using a three-step purification procedure to obtain 32.8 mg of purified hemorrhagic toxin from 700 mg of crude venom. 2. The purified toxin was homogeneous by disc polyacrylamide gel electrophoresis at pH 8.3, and by isoelectric focusing. 3. Hemorrhagic toxin possessed lethal, hemorrhagic and proteolytic activities. These activities of this toxin were inhibited by ethylenediaminetetraacetic acid (EDTA) and ethyleneglycol-bis-(beta-aminoethylether)N,N'-tetraacetic acid (EGTA), but not by cysteine or soybean trypsin inhibitor (SBTI). 4. Its molecular weight was approximately 48 kDa and the isoelectric point was 4.2. 5. Purified preparation hydrolyzed the Asn(3)--Gln(4), His(10)--Leu(11), Ala(14)--Leu(15), Tyr(16)--Leu(17), Arg(22)--Gly(23) and Phe(24)--Phe(25) bonds of oxidized insulin B. chain. 6. The A alpha chain of fibrinogen was first split and B beta chain was cleaved later by this toxin. 7. Hemorrhagic toxin contains 1 mol of zinc and 2 mol of calcium per mol of protein.

Amino Acid Sequence↗
PubMed1989

Comparative study of two arginine ester hydrolases, E-I and E-II from the venom of Crotalus ruber ruber (red rattlesnake).

1. Two arginine ester hydrolases, E-I and E-II from the venom of Crotalus ruber ruber were isolated and characterized. 2. E-I and E-II have molecular weights of 32,000 and 33,000, and isoelectric points of 5.2 and 4.6, respectively. 3. E-I and E-II are active upon the glandular kallikrein substrate, but neither enzyme was shown to have plasma kallikrein substrate hydrolytic activity. 4. E-I has minimal fibrinogen-clotting activity. It was found to induce clotting by catalyzing the hydrolysis of only the A fibrinopeptide from the A alpha-chain of fibrinogen.

Amino Acids↗
PubMed1989

Polypoid squamous cell carcinoma of the larynx. An immunohistochemical study for ras p21 and cytokeratin.

Polypoid squamous cell carcinoma of the larynx consists of two components, namely, squamous cell carcinoma and sarcomatoid spindle cells. To further investigate the histogenesis of the spindle cell component, we studied two cases of polypoid squamous cell carcinoma of the larynx by immunohistochemistry and ultrastructural analysis. Positive staining for ras oncogene p21 and cytokeratin was demonstrated in both squamous cell carcinoma and spindle cell component. Only the latter component was positive for vimentin. Electron microscopic examination showed well-developed desmosomes in spindle cells. These results suggest that the spindle cell component is epithelial in origin and malignantly neoplastic; it originates from mesenchymal metaplasia or squamous cell carcinoma.

Aged↗
PubMed1989

Enhancing effect of Salmonella enteritidis SPA on nonspecific resistance.

The peritoneal macrophages from mice treated with soluble protective antigen (SPA) or lipopolysaccharide (LPS) showed an increase in chemotactic activity, but muramyl dipeptide (MDP)-induced macrophages did not show any enhancing effect. Conversely, the chemotactic activity of mice peritoneal neutrophils was enhanced by SPA, LPS or MDP treatment. The superoxide anion (O2-)-generating activity of SPA-induced macrophages was higher than LPS or MDP. And even 30 days after SPA treatment, a significant increase of O2(-)-generating activity was evident as compared to the control. SPA-induced macrophages showed a higher degree of intracellular killing of Listeria monocytogenes, in vitro, as compared to macrophages obtained from normal mice. In the studies of in vivo protection, the number of bacteria in the liver after challenging with L. monocytogenes was smaller in SPA-treated mice than in untreated mice. Also, SPA-treated mice showed an increased resistance to L. monocytogenes infection.

Acetylmuramyl-Alanyl-Isoglutamine↗
PubMed1989

Post-somatostatin rebound secretion of growth hormone is dependent on growth hormone-releasing factor in unrestrained female rats.

To examine the characteristics of GH secretion following the termination of the infusion of somatostatin, unrestrained adult female Wistar rats were subjected to repeated infusions of somatostatin separated by 30-min control periods. When somatostatin was infused for 150 min at a dose of 3, 30 or 300 micrograms/kg body wt per h, the magnitude of the rebound GH secretion increased in a dose-dependent manner. The infusion of somatostatin at a dose of 300 micrograms/kg body wt per h for 60, 150 or 240 min progressively augmented the size of the rebound GH secretion. When an antiserum to rat GH-releasing factor (GRF) was injected i.v. 10 min before the end of the infusion, the peak amplitude of the rebound GH secretion (300 micrograms/kg body wt, 150 min) was reduced to less than 20% of that of control rats. The rebound GH secretion (300 micrograms/kg body wt per h, 150 min) was augmented by a bolus injection of human GRF (1 microgram/kg body wt). The combined effect of the end of infusion of somatostatin and a bolus injection of GRF on the amount of GH secreted was additive. The plasma GH response to GRF was completely inhibited when human GRF (3 micrograms/kg body wt per h) and somatostatin (300 micrograms/kg body wt per h) were infused simultaneously for 150 min. The magnitude of the rebound GH secretion following the termination of the co-administration was larger than that following the somatostatin infusion alone, but this rebound was not enhanced by a bolus injection of human GRF.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1989

[A case of temporal arteritis associated with marked elevation of serum IgG, IgA levels].

An 84-year-old woman was admitted to Tokyo Metropolitan Tama Geriatric Hospital because of knee pain, anemia and hyperglobulinemia. On physical examination, evidence of arthritis was observed in both knees. Nodular temporal arteries were palpable with hypertrophy and weak pulsation. The urine was normal except that the sediment contained 20-30 with blood cells per high power view. Laboratory data showed raised erythrocyte sedimentation rate of 150 mm per hour, elevation of beta and gamma globulin and mild anemia. Although the levels of serum IgG, IgA were markedly increased, there was no monoclonal component on immunoelectrophoresis. Light microscopy examination of an aspirated specimen of bone marrow showed slight hypocellularity and mild plasmacytosis. However, atypical plasma cells were not observed. Radiographs of the knee showed narrowing of the joint space and calcification of articular cartilage and meniscus. Biopsy of the left temporal artery revealed typical findings of giant cell arteritis. The administration of prednisolone resulted in rapid normalization of laboratory findings. But her arthralgia, which had been relieved by analgesics after admission, was worsened if she took prednisolone without analgesic. Therefore, analgesics were given again with prednisolone for the control of the arthralgia.

Aged↗
PubMed1989

[Thallium-201 myocardial perfusion imaging during transient coronary occlusion at the time of PTCA: comparison with stress imaging].

To evaluate myocardial perfusion during transient coronary arterial occlusion, thallium-201 was administered intravenously during percutaneous transluminal coronary angioplasty (PTCA) in 12 patients with effort angina, and the resulting perfusion images were compared with those of exercise stress obtained before PTCA. Thallium-201 was injected at the last inflation of an angioplastic balloon and occlusion was maintained for 60 to 90 sec. Three projections of planar images were obtained immediately after PTCA, using a portable gamma camera in an angiography room. These perfusion images obtained during PTCA and exercise were visually interpreted and compared. Myocardial perfusion defects due to the responsible vessel occlusion were observed at early imaging after PTCA, and were fully redistributed three hrs post injection. In 10 patients without angiographically imaged collateral vessels, there were no significant differences in perfusion between images during PTCA and during exercise. Two patients whose collaterals were observed during coronary angiography before PTCA had higher perfusion scores during PTCA than during exercise. We concluded that intravenous injection of thallium-201 during PTCA is a useful means for assessing alteration of myocardial perfusion due to transient coronary occlusion without increasing the risk of angioplastic procedures, and that it provides more precise information about the jeopardized myocardium, perfused by antegrade blood flow.

Angioplasty, Balloon↗
PubMed1989

A simple culture method of fat cells from mature fat tissue fragments.

To obtain immature fat cells in vitro, we used a primary culture of undigested mature fat tissue fragments. The immature fat cells, i.e., fibroblast-like fat cells, proliferated extensively from the fat tissue and differentiated after reaching confluence. The process of differentiation was assumed by the development of intracytoplasmic lipid droplets and by the triglyceride content in the cells. Cellular differentiation was induced in high percentages (over 70-80%) of the cells in the medium containing high glucose concentrations (200 mg/dl) supplemented with 10-20% newborn calf serum. The intracellular accumulation of triglyceride was also enhanced by insulin administration. In these cells, a reciprocal relationship was observed between proliferation and differentiation. Fibroblast-like fat cells derived from mature fat tissue in this simple culture system are suitable for the study of the proliferation and differentiation of immature fat cells.

Adipose Tissue↗
PubMed1989

[An examination of left ventricular peak filling rate and ventricular relaxation rate by simultaneous acquisition of radionuclide ventriculography and left ventricular pressure].

We investigated whether peak filling rate (PFR) obtained from ECG gated radionuclide ventriculography (RNV) reflects left ventricular (LV) relaxation rate or not. Five patients with angina pectoris, 5 patients with old myocardial infarction and 6 controls were studied by simultaneous acquisition of RNV and LV pressure. RNV was performed in modified left anterior oblique position before and during angiotensin II (A II) infusion to elevate their blood pressure about 25 mmHg (A-1) and 50 mmHg (A-2). The data were acquired in a list mode and LV volume curves were reconstructed by forward and backward gating from the R wave of ECG. Actual PFR and corrected PFR by stroke volume (/SV), by end diastolic volume (/EDV), by instantaneous volume (/IV) were calculated from LV volume curve and its first differential curve. LV pressure was simultaneously measured by the catheter-tip micromanometer, and the time constant (T) of assumed exponential decline in LV pressure was calculated as index of LV relaxation rate. Although there was no correlation between actual PFR and T, corrected PFR (/EDV) and PFR (/IV) correlated with T. PFR (/EDV) decreased and T increased during A-1 and A-2. Decrease of PFR (/EDV) corresponded with increase of T. Thus, corrected PFR (/EDV) obtained from RNV reflects the rate of LV relaxation, and was considered to be an useful index to evaluate LV diastolic function.

Adult↗