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Biomedical subjects

T Mishima

Publications and source records attributed to T Mishima.

At least 37 records · Page 2Linked to original sources
PubMed1998

Circadian variation of myocardial ischemia in patients with unstable angina pectoris secondary to fixed and/or spastic coronary narrowing.

We investigated the circadian variation of myocardial ischemia in patients with unstable angina using a 24-hour 12-lead electrocardiographic monitoring system with computer analysis. The circadian variation of ischemic attacks in patients who had ST elevation showed a similarity to that of the onset of acute myocardial infarction and most of these patients had vasospasm without organic stenosis; no similarity was seen in patients with organic stenosis.

Aged↗
PubMed1998

Inhibition of tumor invasion and metastasis by calcium spirulan (Ca-SP), a novel sulfated polysaccharide derived from a blue-green alga, Spirulina platensis.

We have investigated the effect of calcium spirulan (Ca-SP) isolated from a blue-green alga, Spirulina platensis, which is a sulfated polysaccharide chelating calcium and mainly composed of rhamnose, on invasion of B16-BL6 melanoma, Colon 26 M3.1 carcinoma and HT-1080 fibrosarcoma cells through reconstituted basement membrane (Matrigel). Ca-SP significantly inhibited the invasion of these tumor cells through Matrigel/fibronectin-coated filters. Ca-SP also inhibited the haptotactic migration of tumor cells to laminin, but it had no effect on that to fibronectin. Ca-SP prevented the adhesion of B16-BL6 cells to Matrigel and laminin substrates but did not affect the adhesion to fibronectin. The pretreatment of tumor cells with Ca-SP inhibited the adhesion to laminin, while the pretreatment of laminin substrates did not. Ca-SP had no effect on the production and activation of type IV collagenase in gelatin zymography. In contrast, Ca-SP significantly inhibited degradation of heparan sulfate by purified heparanase. The experimental lung metastasis was significantly reduced by co-injection of B16-BL6 cells with Ca-SP. Seven intermittent i.v. injections of 100 microg of Ca-SP caused a marked decrease of lung tumor colonization of B16-BL6 cells in a spontaneous lung metastasis model. These results suggest that Ca-SP, a novel sulfated polysaccharide, could reduce the lung metastasis of B16-BL6 melanoma cells, by inhibiting the tumor invasion of basement membrane probably through the prevention of the adhesion and migration of tumor cells to laminin substrate and of the heparanase activity.

Animals↗
PubMed1998

Detection of myocardial ischemia with a computer-assisted 12-lead 24-hour ECG monitoring system (EAGLE) in patients with suspected unstable angina.

This study was undertaken to evaluate the diagnostic value of a new device, the 'EAGLE' computer-assisted multiple-lead long-term electrocardiography (ECG) monitoring and analyzing system, in patients with suspected unstable angina, and to compare the results with the Holter monitor. A total of 101 patients with a history of suspected unstable angina underwent a simultaneous 24-h examination with the EAGLE and 2-channel Holter monitors. The diagnosis of unstable angina was established in 70 patients: 41 had significant organic stenosis, and 29 had coronary spasm. Ischemic ST deviations were detected 229 times in 44 patients (62.9%) with the EAGLE system and 101 times in 20 patients (28.6%) with the Holter monitor. The sensitivity of myocardial ischemia in unstable angina with the EAGLE system was significantly higher than that with Holter monitor (62.9 vs 28.6%, p<0.05). The difference of sensitivity was due mainly to the low detection rate of the Holter monitor for asymptomatic myocardial ischemia (EAGLE vs Holter; 187 times vs 72 times) and myocardial ischemia in the infero-posterior area in patients with organic stenosis (30 times vs none). It is concluded that the EAGLE system is a sensitive tool for the diagnosis of unstable angina in patients without significant ECG changes, and an excellent tool for evaluating silent myocardial ischemia or myocardial ischemia of the infero-posterior area.

Angina, Unstable↗
PubMed1998

Early experience of minimally invasive valve surgery.

In this paper we report on our early results of minimally invasive cardiac valve surgery. A series of 6 consecutive patients with valvular disease underwent valve repair and valve replacement via a right parasternal incision; aortic valve replacement 3, mitral valve replacement 1, mitral valve repair 2. There were no intraoperative complications requiring median sternotomy. Five patients had no blood transfusion. There was only one postoperative event; this patient had a sudden massive bleeding from the chest tube after extubation of the endotracheal tube, an immediate re-suture of the aortotomy was performed. The reoperative course was uneventful. Minimally invasive cardiac surgery for aortic and mital valves is an excellent option for most patients affected by isolated valvular disease.

Adult↗
PubMed1997

The correlation between adhesion of schizophyllan to yeast glucan and its effect on regeneration of yeast protoplast.

Schizophyllan, a water-soluble (1-->3)-beta-D-glucan with a triple-helical conformation, adheres to yeast glucan and curdlan gel. As the molecular weight of schizophyllan decreases, both its adhesion to the water-insoluble glucans and its ability to promote the regeneration of yeast protoplasts are reduced. Therefore, we hypothesize that schizophyllan can surround yeast protoplasts by adhering to a fragment of yeast glucan remaining or/and resynthesized on the cell surface and that this encapsulation allows regeneration of the protoplast cells to occur at very high frequency.

Carbohydrate Conformation↗
PubMed1997

Acrophase amplitude of ambulatory blood pressure decreases in migraineurs.

Ambulatory blood pressure was recorded and analyzed in 13 migraineurs during headache-free periods and in 11 healthy subjects. Systolic blood pressure, mean blood pressure, diastolic blood pressure, pulse pressure, and pulse rate were recorded for 48 hours (three times every hour from 6 AM to mid-night, once an hour at night). Circadian variation of blood pressure was analyzed using single cosinor analysis and group mean cosinor analysis methods. Single cosinor analysis identified significant circadian rhythm of systolic blood pressure in 10 of 11 control subjects (90.9%) and 5 of 13 migraineurs (38.5%, P < 0.02 versus controls, Fisher's exact test). Incidences of significant circadian rhythm of mean blood pressure and diastolic blood pressure were 100% and 100% in controls, 46.2% and 53.8% in the migraineurs (P < 0.01, P < 0.02 versus controls). Incidences of significant rhythm of pulse pressure were 36.3% in controls and 38.5% in the migraine group (difference was not significant). Group mean cosinor analysis identified significant circadian rhythm in both the migraine group and the controls. The MESOR (midline estimating statistic of rhythm) values of systolic, mean, and diastolic blood pressures showed no significant differences between the migraine group and the controls. Acrophase amplitudes of systolic, mean, and diastolic blood pressure were 4.2, 5.2, and 5.9 mm Hg in the migraine group, respectively; and 7.2, 7.3, and 7.5 mm Hg in the controls, respectively. These amplitudes of systolic, mean, and diastolic blood pressures in the migraine group were significantly smaller than those in the controls. These data suggest that some migraineurs lose or alter their circadian blood pressure rhythm. Evaluating migraineurs as a group, significant circadian rhythm of blood pressure can be identified and oscillation amplitudes of blood pressures are decreased. The present results suggest that migraineurs may be subject to dysfunction of the circadian rhythm generator and the autonomic nervous system. Possible involvement of serotonergic projections from the raphe to the suprachiasmatic nuclei of the hypothalamus in migraine is discussed.

Adult↗
PubMed1997

[Comparison of echograms by a microscanner and histological findings of the common bile duct, in vitro study].

To confirm the relationship between the layer structure of the common bile duct by a microscanner (MS) and its histological features, we performed a study using the pinning method with needles and catgut. The locations of 67 needles inserted at random depths in 29 slices of the resected common bile duct from 18 patients were confirmed both by a MS and a microscope. The wall of the common bile duct was delineated as a two- (42 points) or three-layer structure (25 points); "low and high" or "high, low, and high echoic layers" from the mucosal side. A fibrotic layer (ss 1) was often (56/67 points, 16/18 patients) seen in the subserosa (ss) containing nerves and vessels larger than 100 mu in diameter. Among the 51 needle echoes demonstrated in the inner hypoechoic layer, 2 were located in the mucosa (m), 12 in the fm, 19 in the af, 17 in the ss 1, and 1 in the fatty layer of the ss (ss 2). Five of the 6 needles in the outer hyperechoic layer were in the ss 2, and 1 was in the pancreatic parenchyma (pa). Four of the 8 needles at the border between the inner hypoechoic layer and the outer hyperechoic layer histologically corresponded to fm, af, ss 1, and pa, respectively, and the other four corresponded to ss 2. From these results, we conclude that the inner hypoechoic layer contains not only m, fm, and af, but also ss 1. Therefore, this should be kept in mind for the preoperative assessment of the depth of bile duct carcinoma by MS.

Bile Duct Neoplasms↗
PubMed1996

Inhibitory effect of a traditional Chinese medicine, Juzen-taiho-to, on progressive growth of weakly malignant clone cells derived from murine fibrosarcoma.

We have investigated the inhibitory effect of oral administration of Juzen-taiho-to, a Kampo (Chinese herbal) medicine, on progressive growth of a mouse fibrosarcoma. Spontaneously regressive QR-32 tumor cells were able to grow progressively in vivo when coimplanted s.c. with a foreign body, gelatin sponge, whereas QR-32 cells alone gradually grew for over 15 days after inoculation and thereafter regressed for up to 25 days. Oral administration of Juzen-taiho-to (40 mg/day/mouse) for 7 days after inoculation of QR-32 cells with gelatin sponge resulted in significant inhibition of tumor growth and prolongation of the survival of the tumor-bearing mice. This growth-inhibitory effect of Juzen-taiho-to observed on day 25 was dose-dependent over the dose range from 4 to 40 mg/day. Treatment with Juzen-taiho-to for 7 days before tumor inoculation with gelatin sponge also significantly suppressed tumor growth examined on day 25, as did the administration of bismuth subnitrate, which is well known to induce metallothionein, an antioxidant. On the other hand, inoculation of progressed tumor cells (QRsP) resulted in growth without gelatin sponge, leading to death in syngeneic mice. Administration of Juzen-taiho-to for 7 days after inoculation of QRsP cells resulted in a decrease of the tumor growth and prolongation of the survival of mice, but the effect was less than that on the growth of QR-32 regressor tumor after coimplantation with gelatin sponge. These results suggest that the inhibitory effect of Juzen-taiho-to is partly associated with prevention of gelatin sponge-elicited progressive growth, probably mediated by endogenous factors including antioxidant substances, in addition to the augmentation of host-mediated antitumor activity.

Administration, Oral↗
PubMed1996

Degradation of beta 1-->6 galactofuranoside linkages in the polysaccharide of Fusarium sp. M7-1 by endo-beta-galactofuranosidase from Bacillus sp.

A polysaccharide, in which the main part of the side chains were depleted, was prepared from the acidic polysaccharides of Fusarium sp. M7-1 by digestion with lyase of Cellulomonas sp. and mild acid treatment. This polysaccharide was degraded into several fragments, neutral oligosaccharides, neutral polysaccharide, and acidic polysaccharide, by an enzyme, endo-beta-galactofuranosidase, produced by Bacillus sp. The main components of the oligosaccharides were isolated and identified as Gal[sequence: see text] The molecular mass of the neutral polysaccharide fragment was estimated to be about 6000 Da by gel filtration chromatography. The polysaccharide fragment consisted of an alpha 1-->6 linked mannan main chain to which various sugars, namely Glc, Man, and Rha were attached through alpha 1-->3 (or 2) linkages. The molecular mass of the acidic polysaccharide fragment was estimated to be about 6000 Da from the amounts of the reducing terminal galactose. The chemical structures of the oligosaccharides derived from the acidic polysaccharide fragment by mild acid hydrolysis were identified as reported structural units [Iwahara et al., J. Biochem., 112, 355-359 (1992)]. The structure of the mild-acid-resistant part of the acidic polysaccharide fragment was assumed to be a polyuronide to which various sugars such as Glc, Man, and GlcNac are attached as the side chains. The linkage modes of each sugar are not clear.

Bacillus↗
PubMed1995

Effects of degraded schizophyllans on regeneration of protoplast cells of Saccharomyces cerevisiae.

Schizophyllan was heated at 100 degrees C in 85% dimethyl sulfoxide (DMSO) containing 0.01 M H2SO4 for various times, and fractionated by gel-permeation chromatography. Molecular weights (M(r)) of the depolymerized products thus obtained were measured in water and DMSO by GPC-LALLS to estimate their conformations in water. The products with triple helical structure stimulated regeneration of Saccharomyces cerevisiae protoplast cells, while those of single chain conformation were totally inactive.

Hydrolysis↗
PubMed1994

Ultrastructural analysis of peripheral eosinophils in children with bronchial hyperresponsiveness.

To investigate the condition of peripheral eosinophils in patients with bronchial hyperresponsiveness, we examined density distribution profiles and ultrastructure of peripheral eosinophils obtained before and after exercise challenge test. Following exercise challenge test, the number of hypodense eosinophils (< 1.0825 g/ml) was significantly higher in the EIA-positive than in the EIA-negative subjects. Regarding ultrastructural analysis, the ratio of the area of specific granules to the area of cytoplasm (SG/C) per cell was significantly higher in the EIA-negative than in the EIA-positive patients. The ratio of the degranulated area to the area of cytoplasm (D/C) per cell was significantly higher in the EIA-positive than in the EIA-negative subjects. These data suggested that activation of eosinophils in the patients with bronchial hyperresponsiveness occurs during the preinflammatory phase.

Adolescent↗
PubMed1994

[Adrenocortical function in children with near fatal asthma].

The adrenal function of children with near fatal asthma was evaluated by a modified rapid ACTH test. The rapid ACTH tests, which were performed within six months of each life-threatening asthmatic episode, showed extremely low responsiveness. The response in the subjects was significantly lower than that of patients who had received high dose of corticosteroid therapy. It was suggested that the adrenocortical function of children with near fatal asthma had been already suppressed and that adrenal suppression could easily occur in such patients. We advocate the following measures: (1) environmental control, education of patients and their families, physical training accurate medication should be supplied to reduce the use of corticosteroids, (2) sufficient doses of corticosteroids should, however be given to patients with acute exacerbation, (3) not only lung function tests or allergic examinations, but also adrenocortical function tests should be performed on severe asthmatic patients.

Adolescent↗
PubMed1994

[Three cases of typical cryptomeria pollen asthma].

We treated three asthmatic children diagnosed as typical cryptomeria pollen asthma (Cryptomeria japonica). Wheezing started from one to four years after onset of pollinosis. Asthmatic attacks occurred one or several days after pollen counts increased. We could find asthmatic attacks in the years when the pollen counts were higher than in average years. In the laboratory findings, only specific IgE antibody to cryptomeria with its high titer of over 17.5 PRU/ml was detected in these three cases. Allergen inhalation tests were performed with positive results in the two cases, suggesting that these three cases were typical child cryptomeria pollen asthma.

Adult↗