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Biomedical subjects

S Miyazaki

Publications and source records attributed to S Miyazaki.

At least 685 records · Page 38Linked to original sources

Antitumour effect of fibrinogen microspheres containing doxorubicin on Ehrlich ascites carcinoma.

The antitumour activity of fibrinogen microspheres containing doxorubicin has been evaluated against Ehrlich ascites carcinoma in mice in terms of changes in body weight and survival. Tumour cell injections were made on day 0 and microsphere injections on day 1, both intraperitoneally. The suppressive effect of the drug-containing microspheres on increase in body weight was higher than that of the free drug, and tumour-bearing mice given the microspheres lived longer than those given the free drug.

Animals↗

Periodic increase of cytoplasmic free calcium in fertilized hamster eggs measured with calcium-sensitive electrodes.

The hamster egg at fertilization shows transient, periodic hyperpolarizing responses due to a Ca2+-activated K+ conductance. The suggested increase of the intracellular Ca2+ concentration ([Ca2+]i) was measured with Ca2+-sensitive microelectrodes in combination with the voltage-clamp technique. Calculated values of the basal [Ca2+]i before fertilization averaged in the range 0.2-0.4 microM. Insemination of eggs induced periodic Ca2+ transients with exact one-to-one correspondence to periodic, Ca2+-activated K+ currents. They were recorded anywhere in the cytoplasm, even far from the site of sperm-egg fusion, indicating that [Ca2+]i increases in the whole egg upon each response. During a series of responses after insemination the increase in [Ca2+]i reached 1-2 microM in the first three responses and the peak value decreased to 0.7-0.8 microM in the later responses. The rise and decay times of each Ca2+ transient were 6.8 +/- 2.8 and 22 +/- 6 s (mean +/- S.D., n = 36), respectively. No significant difference in the amplitude and time course of the Ca2+ transient was detected in relation to the depth of the cytoplasm about 3-30 micron from the surface. The basal [Ca2+]i increased gradually from 0.39 to 0.56 microM (average in fourteen eggs) during the series of Ca2+ transients. The biological significance and mechanism of the periodic increase in [Ca2+]i and the response time of the Ca2+ electrode are discussed.

Action Potentials↗

The hypotensive effect of single-dose captopril in diabetics.

To determine the role of the kallikrein-kinin (KK) system in patients with diabetes mellitus in relation to nephropathy and/or hypertension, the single-dose effects of captopril (25 mg, p.o.) were examined in 9 control subjects and 32 diabetics (group 1; 11 normotensives without nephropathy, group 2;10 hypertensives without nephropathy, group 3; 11 hypertensives with nephropathy). Significant hypotensive effects of captopril were found in groups 1 and 2 as well as in the control group, but not in group 3. These hypotensive effects were completely blocked by the infusion of ethyl-p-(6-guanidinohexanoyloxy) benzoate methanesulfonate (FOY), a kallikrein inhibitor. The administration of captopril during vehicle infusion induced a significant elevation of plasma renin activity (PRA) at 60 and 120 min after captopril in each group, except for group 3. FOY cancelled these captopril-induced effects on PRA in those groups. No correlation was found between pretreatment PRA and the changes in mean blood pressure (MBP) after captopril during vehicle infusion in whole diabetics. In addition, the daily urinary excretion of kallikrein in group 3 was significantly lower than that in groups 1 and 2 as well as in the control group. These results suggest that the hypotensive action of captopril in diabetics without nephropathy may be largely due to activating the KK system, and that the KK system may be suppressed in hypertensive diabetics with nephropathy.

Blood Pressure↗

Increased sodium influx into erythrocytes in diabetes mellitus and hypertension.

A variety of abnormality has been reported in the cation transport systems in erythrocytes in essential hypertension. To determine the existence of similar abnormality in diabetics with hypertension, sodium (Na+) influx into erythrocytes in the presence of ouabain (measured by using 22Na+), and the Na+ and potassium (K+) content in intact erythrocytes were examined. Subjects, all of whom were Japanese, were divided into 4 groups; 23 nondiabetic, normotensive control subjects without family history of hypertension (control group), 20 patients with essential hypertension (group 1), 21 normotensive diabetics without family history of hypertension (group 2) and 15 hypertensive diabetics (group 3). Na+-K+ pump activity (measured by using 86Rb+) was studied in some of them, too. Na+ influx in group 1 was 0.451 +/- 0.111 m mol/Kg erythrocytes/h, significantly more elevated than that in the control group (0.345 +/- 0.080, p less than 0.001). Na+ influx in group 2 (0.435 +/- 0.094) was significantly greater than that in the control group (p less than 0.005), but no significant difference was found between groups 1 and 2. Na+ influx in group 3 (0.551 +/- 0.128) was significantly higher than that in the control group (p less than 0.001), in group 1 (p less than 0.02), or in group 2 (p less than 0.005). There were no significant differences in Na+-K+ pump activity, or Na+ and K+ content among the 4 groups. These findings suggested that: Na+ influx into ouabain-treated erythrocytes was higher in patients with essential hypertension than in control subjects in Japanese, diabetes mellitus per se might increase Na+ influx, and the elevation of blood pressure in hypertensive diabetics as well as in essential hypertensives might be related to the increased Na+ influx.

Adult↗

Fusiform posterior cerebral artery aneurysm treated with excision and end-to-end anastomosis. Case report.

A case of a ruptured fusiform aneurysm of the posterior cerebral artery is reported. The aneurysm was excised and end-to-end anastomosis was carried out between the two ends of the posterior cerebral artery. There is no previous report of a posterior cerebral artery aneurysm treated with this technique. The pertinent literature is reviewed and the significance of this technique in the treatment of unclippable cerebral aneurysms is discussed.

Adult↗

[Concomitant therapy with cefmenoxime and cefsulodin for refractory complicated urinary tract infection (especially caused by Pseudomonas aeruginosa)].

Cefmenoxime (2 g) and cefsulodin (1 g) were given twice daily for 5 days by concomitant intravenous drip infusion (mixed infusion) to 135 patients with complicated urinary tract infection (c-UTI) probably caused by Pseudomonas aeruginosa. The clinical efficacy was evaluated according to the criteria proposed by the UTI committee in Japan. Ninety one subjects met the criteria for c-UTI and were evaluable for drug efficacy. P. aeruginosa was detected in 44 cases (including mixed infection with other organisms). The overall efficacy rate was 73% of the 91 cases; 75% of the 44 cases with P. aeruginosa and 70% in the 47 cases without P. aeruginosa infection. As to bacteriological response, the eradication rate was 91% (105/116) for all cases. By organism, the eradication rate for P. aeruginosa, Serratia spp. and Citrobacter spp. were 82 (36/44), 100 (12/12) and 100% (10/10), respectively. The eradication rate for gram-negative rods was 93% (99/107). Twenty-three strains appeared after treatment, and the majority of them (13) were yeast-like organisms. There was only one strain of P. aeruginosa. As for side effects, eruption was found in 2 cases. Cefmenoxime and cefsulodin were administered concomitantly to patients with c-UTI which was suspected to be caused by P. aeruginosa. The high overall efficacy rate of about 70% on the average was obtained regardless of the causative organism and disease state. The eradication rate of as high as about 90% was obtained excluding Enterococcus faecalis. Neither severe side effects nor abnormal laboratory values were found. It appeared, therefore, that this dosage regimen was useful for the treatment of refractory complicated urinary tract infection.

Anti-Infective Agents, Urinary↗