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T Toyosaki

Publications and source records attributed to T Toyosaki.

23 records · Page 2Linked to original sources
PubMed1990

Significant myocardial pathology and increase of alpha 1-adrenergic receptor number affecting the arrhythmogenic condition in cases with ventricular tachycardia.

To study the pathogenesis of idiopathic ventricular tachycardia with left bundle branch block morphology (LBBB-VT), histopathological findings in 34 patients and adrenergic receptor (AR) density obtained by micro-autoradiography in 11 patients were analyzed, using endomyocardial biopsy samples. According to the ventricular volume, we divided the patients into 3 groups. Group A patients (n = 8) were diagnosed as having arrhythmogenic right ventricular dysplasia (ARVD) showing right ventricular enlargement, group B patients (n = 7) showed decreased left ventricular function and/or enlarged left ventricle, and group C (n = 19) included patients with idiopathic ventricular tachycardia (VT) without enlargement or dysfunction of either ventricle. Histologically, there was a high incidence of significant pathology showing myocardial hypertrophy, degeneration, abnormal branching, and interstitial fibrosis in all groups (group A, 100%; group B, 86%; group C, 56%). There was a higher incidence of fatty tissue infiltration in groups A (100%), B (71%), C (48%) than in the control groups. As for AR, specific grains of alpha 1- and beta-AR were 23.0, and 18.3 (grains/25 x 25 mm square) respectively, in patients with LBBB-VT. The number of alpha 1 grains in patients with LBBB-VT was apparently higher than in the control group, sick sinus syndrome (SSS; 11.2), and the beta-AR density in the LBBB-VT group was the same as in the control group (SSS; 15.4). We concluded that the significant pathology in cases with VT might affect the arrhythmogenic condition. Moreover, these results suggested that the increase in the number of alpha 1-AR might have a great influence in idiopathic VT.

Adult↗
PubMed1990

[Radionuclide assessment of cardiac involvement in patients with sarcoidosis].

This study was aimed to determine whether nuclear methods were useful for examining cardiac pathology and for making a decision of corticosteroid therapy in patients with sarcoidosis. Thirty six patients were divided into two groups; GpA consisted of 19 patients with cardiac sarcoidosis and abnormal ECG findings, and GpB of 17 patients with sarcoidosis without ECG abnormalities. Cardiac uptake of 67Ga-citrate in 2 and 99mTc-PYP in one of GpA was observed and steroid therapy resulted in the disappearance of the uptake. 201Tl-CL cardiac tomograms disclosed perfusion defects in 10 of 14 patients (71%) in GpA, including defects with redistribution in 8 of the 10 pts, but only one case in GpB. Radionuclide ventriculography using 99mTc-RBC revealed abnormal response of left ventricular (LV) function to exercise and LV dysfunction in GpA. These data suggest that nuclear study is a useful tool for diagnosing cardiac sarcoidosis, evaluating therapeutic effectiveness and long-term follow-up in patients with sarcoidosis.

Adult↗
PubMed1985

Antithrombogenic elastomers: novel anticoagulant/complement inhibitor-controlled release systems.

We have introduced novel synthetic anticoagulant and complement inhibitors for controlled release systems with high biocompatibility. These drugs were molecularly designed for extremely high biospecific inhibition, are readily soluble in polar organic solvents, such that they have versatile applications in commonly used hydrophilic polymeric systems via an easily attainable one-step co-casting technique at a given amount of loading. Another characteristic feature of the controlled release system is that both release rate and duration are controlled by the material, formulation and fabrication variables. These are easily manipulated by the hydrophilicity of polymers, amount of loading and film thickness. The drug-impregnated system may generate a new dimension in the formulation of controlled release biocompatibility.

Animals↗
PubMed1983

Study of wall effect on the flow of milk in capillary.

Dependence of the viscosity of milks on the bore-size of capillary viscometer has been studied at 25 degrees C. Viscosity measurements were carried out with a Maron-Belner type low shear capillary viscometer with various capillary radii (0.0190-0.076 cm) within the shear stress range of 0.2-30 dynes/cm2 at the capillary wall. Each milk showed non-Newtonian flow behavior and dependence on the size of the capillary. The viscosity of human fresh milk and cow's fresh milk decreased with the decreases in the capillary bore-size within the range of shear stress studied, and the viscosity of homogenized milk, although similar phenomena as above were observed in higher shear stress, decreased with the decrease in the capillary bore-size at the range of lower shear stress. The difference in characteristics of capillary bore-size dependence on viscosity may be attributed to the difference in the behavior of fat droplets existing near the wall at which thermal motion of fat droplets will be hindered by the existence of capillary wall. The results were represented by the modified Ree-Eyring generalized flow formula for a flow system containing one Newtonian flow unit and one non-Newtonian flow unit which included additional terms dependent on the capillary bore-size. The viscosity equation suitable for analysing the dependence of viscosity on the capillary bore-size at entire ranges of rate of shear, was derived by assuming the wall layer. Composed of double layers (of thickness do and di - do) in the flowing liquid in capillary tube, and by combining this equation with the modified Ree-Eyring equation, the values of do and di were calculated.

Animals↗