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Biomedical subjects

H Sugihara

Publications and source records attributed to H Sugihara.

At least 451 records · Page 25Linked to original sources
PubMed1984

Simultaneous changes of left ventricular and left atrial size and function in normal subjects during exercise.

We performed dual M-mode exercise echocardiography, which records left ventricular (LV) and left atrial (LA) echocardiograms simultaneously, in 10 normal subjects to investigate mechanisms of cardiac adaptation to dynamic exercise. The LV end-diastolic dimension (EDD) increased significantly as exercise increased from mild to moderate (3-5%, p less than 0.05 and 0.001). At peak exercise the EDD was slightly increased, but it returned to the baseline during recovery. The LV end-systolic dimension (ESD) showed a progressive decrease with the severity of exercise (5-13%, p less than 0.05 and 0.001). It decreased further immediately after exercise (17-20%) and then returned to the resting value. The LV stroke dimension and fractional shortening increased as exercise changed from mild to moderate and reached a plateau at peak exercise. During recovery, they showed a transient increase and then decreased. By contrast, the LA dimensions, both maximum and minimum, increased significantly as exercise changed from mild to moderate (15-16% and 16-19%, p less than 0.01 and 0.001, respectively), but they were lower at peak exercise (12 and 14%). They returned rapidly to the resting values immediately after exercise. Thus, during exercise, LV function is augmented by the Frank-Starling mechanism in combination with increased contractility, while the LA is enlarged to receive the increased venous return accompanying dynamic exercise. These exercise-induced changes in LV performance return gradually to the resting state, but LA size recovers rapidly after the cessation of exercise.

Adolescent↗
PubMed1984

An improved procedure for the histochemical demonstration of cathepsin D by the mercury-labeled pepstatin method.

The desirable fixation conditions for the histochemical demonstration of cathepsin D using mercury-labeled pepstatin as an enzyme inhibitor were examined biochemically and histochemically. Four well known fixatives, namely, glutaraldehyde (GA), paraformaldehyde (PFA), glutaraldehyde with paraformaldehyde (GA-PFA) and periodate-lysine-paraformaldehyde (PLP), were applied to the prefixation of tissues prior to the reaction of the labeled inhibitor to the enzyme-active site. The effects of fixatives on cathepsin D were biochemically examined using subcellular fractionated lysosomes. Cathepsin D from rat liver lysosomes was rapidly inactivated by the fixatives containing glutaraldehyde, i.e., GA and GA-PFA, whereas the activity of cathepsin D was sufficiently maintained after fixing the enzyme in the PFA or PLP preparations. Effects of the PLP fixative on lysosomal cathepsin D in liver tissues using the mercury-labeled pepstatin method were also studied histochemically. The best result for the visualization of lysosomal cathepsin D in liver tissues was obtained using the PLP fixative with the prefixation time of three hours or more.

Animals↗
PubMed1984

[A case of Müllerian adenosarcoma of the uterus].

A case of Müllerian adenosarcoma of the uterus is reported. This is a low-grade malignant tumor situated between fibroadenomas and carcinosarcomas in the mixed mesodermal tumors. A 69-year-old woman complaining of an abdominal mass, underwent surgical resection of a tumor of the uterus. The tumor was divided into two parts, i.e. polypoid tumor in the endometrial cavity and nodular tumor in the myometrium. The 2 tumor types showed continuity. Microscopically, it was a so-called mixed tumor consisting of a glandular element of benign epithelial cells and an undifferentiated sarcoma; it was diagnosed as adenosarcoma.

Aged↗
PubMed1984

[Biology of cancer cell-stroma interaction in carcinogenesis and cancer progression].

Cancer cells are dependent on physical and chemical supports of stroma no less than non-cancerous cells and tissues are. The role of stroma should, therefore, be important in genesis and progression of cancers growing in vivo. But this aspect underlying carcinogenesis and manifestation of human cancers has long been neglected or attracted less attention in the investigations of oncology. Focusing particular attention on parenchyma-stromal interaction in gastrointestinal mucosa, the authors have found that, quite unexpectedly, in normal gastric as well as intestinal mucosa of all the animal species so for studied, vascularity is always poorly developed in the generative cell zones. Cross-sectional area of vascular bed is markedly reduced in this zone. Application of Hagen-Poiseulle law revealed that the reduced total cross-sectional area, resulting in a rapid drop in hydrostatic pressure, creates here a situation particularly favorable for proliferating cell population. Since the transport of water soluble material together with tissue fluid through the capillary wall is driven by the hydrostatic pressure, the generative cell zones are found to be present at the site where the turnover of the material is the most active. Before the zone of the rapid pressure drop, there appears zone of relatively high intravascular hydrostatic pressure, where secretory function seems to be facilitated. This zone, as is well known, corresponds to glandular portion of the mucosa. After the zone of the rapid pressure drop (in surface of the mucosa), zone of a low intravascular hydrostatic pressure appears, where absorptive function is to be facilitated. Within such zones, in gastric mucosa surface epithelium and in intestinal mucosa absorptive villi cells are located. It is likely that architecture of gastrointestinal epithelium and vascular pattern in the stroma is closely correlated and that the former is determined, at least partly, by the latter. When human gastric mucosa shows intestinal metaplasia, the vascular pattern is always of the type of intestine. Investigating causal relationship of the changes in vascular pattern and epithelial metaplasia, we found that, in human gastric mucosa, vascular architecture began to shift to the intestinal pattern, though not complete, when incipient changes of chronic gastritis became manifest. This is peculiar to human gastric mucosa and thought to be species specific characteristics of mucosal stroma in human stomach.(ABSTRACT TRUNCATED AT 400 WORDS)

Adenocarcinoma, Mucinous↗
PubMed1984

[A case of subependymoma of the septum pellucidum].

A 72-year-old-female was admitted because of slight disorientation and urinary incontinence. CT scan on admission revealed isodensity mass in the portion of the septum pellucidum and dilated lateral ventricle with patcy enhancement. A patient underwent the right frontal osteplastic craniotomy and subtotal removal of the tumor. Microscopical examination of the removed tumor tissue revealed a typical finding of subependymoma. In the previous literature subependymoma of the septum pellucidum has been reported only seven cases. We reported a rare case of subependymoma derived from the septum pellucidum, and histopathology and symptomatology of the tumor were discussed with the literature.

Aged↗
PubMed1983

Immunocytochemistry of the Microtubules of fat-laden cells. Brown fat cells and adrenocortical cells in primary monolayer culture.

Cytoplasmic microtubules of fat-laden cells containing fine lipid droplets, such as brown fat cells and adrenocortical cells, were studied in relation to the metabolism of intracellular lipid. In these cells, the amount and distribution of lipid droplets reflect the state of inherent cellular function. Materials used were primary monolayer culture of fetal rat brown fat cells and that of bovine adrenocortical cells. The method was the immunocytochemistry with anti-tubulin antibody. When brown fat cells were being lipolyzed or the steroidogenesis of adrenocortical cells were being stimulated, the cytoplasmic microtubules in the cells were organized in a radial pattern in response to the behavior of the lipid droplets. It is assumed that the microtubules were in the regulation of cellular function in terms of the metabolism of lipid droplets in these cells. We have devised, in the course of the current study, a double fluorescence technique as an observational method whereby microtubules were observed immunocytochemically and lipid droplets by a secondary fluorescence with phosphine E staining.

Adipose Tissue, Brown↗
PubMed1983

Purification and properties of a lethal, hemorrhagic protein, "Mucrotoxin A", from the venom of the Chinese habu snake (Trimeresurus mucrosquamatus).

Mucrotoxin A was purified from the lyophilized venom of Trimeresurus mucrosquamatus using gel filtration on a Sephadex G-100 column, followed by chromatography on CM-Sephadex C-50 and DEAE-Sephadex A-50. By these procedures, 14 mg of purified preparation could be obtained from 1 g of crude venom. The purified preparation was homogeneous by disc electrophoresis on polyacrylamide gel at pH 8.3, isoelectric focusing and by the presence of one precipitin line on immunodiffusion. Mucrotoxin A possessed both lethal and hemorrhagic activities, but it did not show caseinolytic activity. Its molecular weight was approximately 94,000 and the isoelectric point was 4.3. Mucrotoxin A contains approximately 3 moles of Ca and 2 moles of Zn per mole of toxin. The amino acid composition of Mucrotoxin A was determined. No carbohydrate was present.

Animals↗
PubMed1983

Isolation and characterization of fibrinogenase from western diamondback rattlesnake venom and its comparison to the thrombin-like enzyme, crotalase.

A new type of fibrinogenase was isolated from the venom of the western diamondback rattlesnake (Crotalus atrox). Unlike thrombin, the newly isolated fibrinogenase did not cause formation of a fibrin clot. Various properties of the fibrinogenase we isolated were compared with crotalase isolated from the venom of C. adamanteus. It was found that fibrinogenase has considerable similarity to crotalase isolated by Markland and Damus in 1971. Crotalase is a thrombin-like enzyme and produces a fibrin clot from fibrinogen. The A alpha chain of fibrinogen was first split and the B beta chain was cleaved later. The fact that no fibrin clot forms indicates that the cleavage sites in A alpha and B beta chains of fibrinogen must be different from thrombin sites. The fibrinogenase also released bradykinin by interacting with plasma proteins. It hydrolyzed TAME (p-toluenesulfonyl-L-arginine methyl ester), BAEE (N-benzoyl-L-arginine ethyl ester). TLME (N-tosyllysine methyl ester) but not BAA (N-benzoylarginine amide), TAA (N-tosylarginineamide) or ATEE (N-acetyltyrosine ethyl ester). The enzyme is an acidic protein with pI of 4.6 and a mol. wt of 31,000. It consists of 272 total amino acid residues, 21% of which are acidic amino acids. Fibrinogenase is a specific form of protease. A newly liberated amino group after hydrolysis of dimethyl-casein can be detected by the reagent trinitrobenzenesulfonic acid (TNBS). Fibrinogenase differs from trypsin as the soybean trypsin inhibitor does not inhibit the enzyme's action.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acids↗
PubMed1983

Hormonal sensitivity of brown fat cells of fetal rats in monolayer culture.

The primary monolayer culture of brown fat cells was performed with the brown adipose tissue of fetal rats as the material. Brown fat cells in the culture were highly sensitive to some hormones. Insulin had a marked effect of lipogenesis and it made the cells contain large multilocular lipid droplets. Lipolysis is also mediated by hormones, e.g., epinephrine or ACTH etc., and lipolytic process was controlled through cyclic AMP system. Brown fat cells of fetal rats in monolayer culture seem to be a suitable material for long-term experiment of lipogenesis and lipolysis.

Adipose Tissue, Brown↗
PubMed1983

Left ventricular size and performance during graded supine exercise in normal subjects.

To investigate left ventricular size and performance during graded submaximal exercise, 14 normal subjects with a mean age of 21 years exercised in a supine position to achieve the target heart rate. Using two-dimensional echocardiography, we recorded and analysed the left ventricular (LV) cross-sectional area and internal dimension at the level of the tips of the mitral valve at rest and during mild, moderate and severe exercise. The heart rate and systolic blood pressure increased substantially from rest to peak exercise (71 +/- 11 to 162 +/- 10 beats/min, 122 +/- 10 to 204 +/- 22 mmHg). The end-diastolic cross-sectional area and internal dimension (EDA & EDD) increased by 1.1-2.2 cm2 (7-13%) and 0.2-0.3 cm (4-7%), respectively, from mild to moderate exercise, (p less than 0.05-0.001). At peak exercise, however, these decreased and showed no statistically significant difference from the values at rest. The end-systolic cross-sectional area and internal dimension (ESA & ESD) decreased by 1.1 to 1.6 cm2 (14-20%) and 0.2-0.3 cm (7-10%), respectively, from moderate to severe exercise (p less than 0.01-0.001). However, the end-systolic values during mild exercise were not significantly different from those at rest. The stroke area (EDA-ESA) and dimension (EDD-ESD) increased by 1.6-2.6 cm2 (19-31%) and 0.2-0.6 cm (25-38%), respectively, during all levels of graded exercise (p less than 0.05-0.001). The percent change of LV cross-sectional area and internal dimension during systole increased gradually from rest to moderate exercise (51.0 +/- 7.1 to 61.9 +/- 4.4%, 35.4 +/- 3.9 to 45.0 +/- 3.7%), respectively, and showed no further increase during peak exercise. The mean circumferential fiber shortening velocity increased sharply from rest to peak exercise (1.27 +/- 0.14 to 2.25 +/- 0.21 circ/sec). These results suggest that the Frank-Starling mechanism operates during mild to moderate exercise, and contractility increases markedly at moderate to severe exercise levels as cardiac performance is augmented during graded submaximal exercise.

Adolescent↗
PubMed1983

[Analysis of coronary hemodynamics in exercise by T1-201 scintigraphy: examination of rates of change of cardiac output, myocardial blood flow distribution, coronary blood flow and coronary vascular resistance].

From our observation that initial distribution of 201T1 in tissue is mainly dependent on blood flow distribution, we designed the method to obtain the rates of change of coronary blood flow and coronary vascular resistance and applied it to the analysis of coronary hemodynamics in patients with ischemic heart disease during submaximal exercise. We measured the rates of change of cardiac output (delta CO) and myocardial blood flow distribution (delta Fract ) in two occasions by the sequential two injections of T1, and obtained the rate of change of coronary blood flow (delta Flow) from delta CO and delta Fract . Using the rate of change of mean blood pressure, we calculated also the rate of change of coronary vascular resistance (delta CVR). The initial components of histograms of the right ventricle by the first and second injections of T1 were fitted into gamma function curve. S1 and S2 were the areas bounded by the curve and baseline of the first and second injections, and then the cardiac output ratio was estimated by R X S1/S2, where R was the dose ratio measured by another camera system. The five min count rates on the myocardium by the first (H1) and second (H2) injections of T1 were calculated five min after the injection. H2 was approximately H1 X R in the same condition of T1 injection but H2 was not equal to H1 X R, when the T1 injection was done in the different loading condition. Therefore the rate of change of myocardial blood flow distribution was calculated as delta Fract = (H1 X R-H2)/H2.(ABSTRACT TRUNCATED AT 250 WORDS)

Cardiac Output↗
PubMed1982

Presence of zinc in proteolytic hemorrhagic toxin isolated from Agkistrodon acutus venom.

1. Hemorrhagic toxin (Ac1-proteinase) was isolated from the venom of Agkistrodon acutus (Formosa) and the zinc content was determined (1.15 mol/mol protein). The results we extensively compared with hemorrhagic toxin e of Crotalus atrox venom (U.S.A.). Comparable results were obtained for zinc content, hemorrhagic and proteolytic activities for native hemorrhagic toxins from two different venoms. It is of interest that the zinc content of hemorrhagic toxins is identical even though the venoms are obtained from snakes inhabiting totally different continents. 2. Zinc content, hemorrhagic and proteolytic activities were compared before and after the removal of zinc. It was found that both hemorrhagic and proteolytic activities disappeared upon removal of the zinc. 3. Zinc content of all hemorrhagic toxins with proteolytic activity reported so far were also compared and it is concluded that regardless of their geographic origin, zinc is present in venom hemorrhagic toxins on a unimolar basis. 4. When zinc is removed there is a drastic change in the low-frequency region of the Raman spectrum suggesting the presence of a zinc ligand co-ordination. The decrease of alpha-helical content and increase of random coil are reflected in the amide I and III bands of Raman spectroscopy after the removal of zinc. Increase of random coil and the loss of zinc are probably responsible for the loss of hemorrhagic and proteolytic activities.

Animals↗