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Biomedical subjects

Y Kai

Publications and source records attributed to Y Kai.

At least 181 records · Page 10Linked to original sources
PubMed1986

Experimental study on size-limitation of myocardial infarct in swine produced by a coronary balloon-catheterization. I. Preliminary report; morphometry of infarct size.

Experimental myocardial infarction was produced in 15 subject swine using a balloon catheter to occlude the left anterior descending coronary artery (LAD). After 30 minutes obstruction, the LAD was reperfused, and then the animals were sacrificed at 3 hours, 6 hours, 24 hours, and 48 hours after the onset of coronary occlusion, respectively. During and after the experiment they were investigated physiologically and pathomorphologically to measure the size of myocardial infarct, and the obtained results are as follows; Experimentally produced myocardial infarcts could be detected histopathologically by routine gross and light-microscopical means in the group which had suffered from ischemia for over 24 hours till sacrifice. Ischemic areas could not be distinguished from normal areas of the myocardium by routine techniques, but could be identified enzyme-histochemically in the groups observed for less than 6 hours. The mean weight ratio of infarcted myocardium to total ventricular myocardium was 25 +/- 3.6%. This method was useful for measuring infarct size.

Animals↗
PubMed1986

[Biliary excretion and clinical evaluation of cefoperazone in the biliary tract infections].

Biliary excretion Cefoperazone (CPZ) in a dose of 1 g was intravenously injected to each of 13 cases with obstructive jaundice. Entire bile was collected through percutaneous transhepatic cholangiodrainage (PTCD) catheter in every 1 hour for 6 hours. The mean concentration of CPZ in serum was 112.1 +/- 17.8 micrograms/ml (mean +/- S.E.) at 1 hour and 55.1 +/- 19.2 micrograms/ml at 6 hours after injection. The mean recovery of CPZ in bile within 6 hours was 1.13 +/- 0.60%. Average CPZ concentrations in bile were 64.0 +/- 45.8 micrograms/ml in the 1 hour fraction, 142.7 +/- 78.4 micrograms/ml in the 2 hours fraction and 72.2 +/- 34.0 micrograms/ml in the 6 hours fraction. Biliary excretion of CPZ was low in cases where the serum concentration of total bilirubin was high, but maximum CPZ level in bile in patients with higher serum bilirubin concentrations than 30 mg/dl was still more than 3 micrograms/ml. Clinical evaluation. CPZ was administered to 43 patients with biliary tract infections. The efficacy ratio was 88.4% (excellent and good cases) in all cases, and especially high in cases with cholecystolithiasis. But no difference in efficacy ratio was observed among cases with cholecystolithiasis, choledocholithiasis without gallstone and cases subjected to PTCD. In 10 patients examined by ultrasonography, 8 cases showed reduced diameters of gallbladder. No adverse effect of CPZ was noted in any cases. These results suggest that a fairly large portion of CPZ was excreted through bile and that CPZ is a very useful drug for the treatment of biliary tract infections.

Adult↗
PubMed1986

[Clinical studies of efficacy of piperacillin against complicated urinary tract infections].

Clinical efficacy of piperacillin against 74 cases with complicated urinary tract infection was examined. Piperacillin was administered at the dose of 4 g (2 g twice daily) through intravenous drip infusion. The overall clinical value was rated in "excellent", in 9 cases, "moderate" in 34 cases and "poor" in 31 cases with a total efficacy of 58.1%. In the analysis of clinical values based on background, its efficacy was statistically significantly lower in the patients at a higher age, those with complication of diabetes mellitus, and those with indwelling catheter. In operated cases compared to non-operated cases, it was suggested to be more effective for improving the disturbances in urinary flow as a result of the removal of the underlying conditions by the operation. As to bacteriological efficacy, 64 out of 95 strains (67.4%) isolated were eradicated following its administration. Microbes which appeared after its dosing belonged to 9 classes of 18 strains, of which 5 strains (27.8%) of Serratia were identified. Side effects were 2.5% (3/119), no serious cases appeared. Changes in laboratory examination results were elevated GOT (2.5%), GPT (1.7%), and ALP (0.8%) values, all being transient hanges.

Adult↗
PubMed1985

Structure of ferricytochrome c' from Rhodospirillum rubrum at 6 A resolution.

The structure of a ferricytochrome c' extracted from Rhodospirillum rubrum has been determined at 6 A resolution by the X-ray crystallographic method. The crystals, obtained by dialyzing the protein solution against polyethylene glycol 4000, belong to the hexagonal space group P6(1). Two heavy atom derivatives were obtained by soaking the native crystals in K2PtCl6 and CH3HgCl solution. The phases calculated by the multiple isomorphous replacement method gave an overall figure of merit of 0.90 at 6 A resolution. The resulting electron density map showed the molecular boundary clearly, and gave molecular dimensions of 50 X 25 X 30 A for a monomer molecule. From visual examination of this map, the cytochrome c' from Rhodospirillum rubrum has a similar chain-folding pattern to the cytochrome c' from Rhodospirillum molischianum, the structure determination of which has already been carried out.

Crystallography↗
PubMed1984

A new crystal form and preliminary crystallographic data for ferricytochrome c' from Rhodospirillum rubrum.

A new crystal form of ferricytochrome c' from the photosynthetic bacteria, Rhodospirillum rubrum, has been obtained by dialysing protein solution against polyethylene glycol 4000. The crystals belong to the space group P61 (or its enantiomorph P65) with unit cell dimensions: a = b = 51.63 A and c = 155.39 A. The asymmetric unit contains one dimer molecule of 28,000 molecular weight and the solvent content of the unit cell is approximately 38%.

Crystallization↗
PubMed1984

[Chemotherapy of gastric and rectal cancers incorporating non-radical irradiation during remission induction. 1].

For the remission induction therapy of advanced gastric and rectal cancer, 25 cases were treated by non-radical irradiation (total doses: 3000-6000 rad) combined with tegafur, which minimized the tumor mass. For the reduction of tumor mass, a modified method of FAMT was employed and for the maintenance therapy of long-term chemotherapy a modified method of FAMT, MFE, MF or tegarfur alone were performed. Prolongation in survival was obtained with this combination therapy: Of 25 cases, 11 cases survived longer than one year and 6 cases longer then two years. One case of survived rectal cancer obtained disease-free for about 8 years with this treatment. But the observation period was too short to calculate one-year and two-year survival rates of all cases. The indications for application of this combination therapy were as follows; (1) Locally operable cases with myocardial infarct, heart insufficiency, poor risk or refusal of operation, (2) Very aged patients, (3) Locally inoperable cases without clinical metastasis, and (4) Primary lesion of gastric cancer with small metastasis controllable by tegafur. It was concluded that over 3000 rad of irradiation combined with tegafur was necessary to obtain the sufficient radiation effect. As for side effects, loss of appetite , leukopenia and a few case of gastric bleeding by radiation were noted. From the result this treatment modality appears to be valuable in the management of gastric and rectal cancer.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1984

[Combination chemotherapy of mitomycin C and cytosine arabinoside in the intravesical treatment for superficial bladder tumors: report 2. Evaluation of prophylactic intravesical infusion therapy].

Combined chemotherapy of Mitomycin C (20 mg to 30 mg) and Cytosine Arabinoside (200 mg) was given by intravesical infusion to 25 patients with superficial bladder tumor who underwent transurethral treatment for prevention of postoperative recurrence. The prophylactic effect of this therapy was evaluated as follows. 1) The postoperative recurrence rates by the actuarial method were 4.0% in six months, 8.1% in one year, 22.2% in two years, 37.4% in three years and 37.4% in five years. 2) The prophylactic effect on recurrence tended to be marked on primary tumors, solitary tumors, low grade tumors and relatively large tumors. 3) The correlation of doses and the recurrence rate was significantly observed: prophylactic effect tended to increase in proportion to increase of doses of both Mitomycin C and Cytosine Arabinoside.

Adult↗
PubMed1983

[Combination chemotherapy of mitomycin C and cytosine arabinoside in superficial bladder tumors. 1. Evaluation of intravesical infusion therapy].

A combined chemotherapy of Mitomycin C (20-30 mg) and Cytosine Arabinoside (200 mg) was given intravesical by to 37 patients with superficial bladder tumor. The antitumor effect of the therapy was evaluated as follows. 1) The results were: remarkably effective in 12 cases (32.5%); effective in, 14 cases (37.8%); non-effective in 11 cases (29.7%), with overall rate of 70.3%. 2) The antitumor effect tended to be evident in multiple tumors, small tumors, and tumors of low malignancy. 3) Side effects were found in 35.1% of the cases including 24.3% of bladder irritating symptom. 4) The follow-up period ranged from 12 to 60 months with an average of 36.6 months. Recurrence rate was 27.0%. There was a tendency that recurrence occurred more frequently in cases of multiple tumors and small tumors than in other cases.

Adult↗
PubMed1981

The endocrine pancreas in pyridoxine deficient rats.

Because the supplementation of pyridoxine (vitamin B6) improves the glucose tolerance in gestational diabetes and adult onset diabetes, pyridoxine deficiency has been considered to be one of the factors that cause diabetes mellitus. We produced pyridoxine deficient rats by giving pyridoxine-free food with deoxypyridoxine which competitively the activity of pyridoxal phosphate. In these pyridoxine deficient rats plasma insulin during the glucose tolerance test was significantly low as compared with controls. In vitro experiments of pancreas perfusion showed that secretion of insulin and glucagon was impaired in the pyridoxine deficiency. Since the restriction of diet-calorie caused a decrease in arginine-induced secretion of insulin and glucagon from the isolated pancreas, the impairment of the endocrine pancreas may depend on malnutrition. Pyridoxine deficiency is surely one of the factors that impair the endocrine pancreas by multifactorial derangement of metabolism besides the tryptophan-nicotinic acid pathway.

Animals↗
PubMed1980

Stimulatory effect of secretin on pancreatic polypeptide in diabetic patients.

In diabetic patients plasma levels of pancreatic polypeptide (PP) increased four fold after intramuscular injection of secretin (50 CHRU, Eisai Co.) in spite of the lack of response of plasma insulin, plasma glucagon and blood glucose levels. In control subjects, PP levels did not change significantly after secretin injection. Since pancreatic polypeptide has is known to have an inhibitory effect on the exocrine pancreas, the present study suggests the possibility that disturbed function of the exocrine pancreas in diabetic patients could be related to the remarkable response of PP to secretin-stimulation.

Adult↗
PubMed1980

Effects of islet-activating protein (IAP) on blood glucose and plasma insulin in healthy volunteers (phase 1 studies).

Islet-activating protein (IAP) is a new active substance purified from the culture medium of Bordetella pertussis. The active protein possesses a molecular weight of 77,000 and an isoelectric point of pH 7.8. The nature of IAP-action is characterized by enhancement of insulin secretory response to glucose and other stimulants. A single injection of IAP into spontaneous diabetes rats resulted in normalization of their glucose intolerance over a period of a month. Acute and chronic animal toxicity tests showed that LD50 of IAP was 127 micrograms/kg in mice and 144 micrograms/kg in rats. After these animal experiments, phase 1 studies were designed and undertaken to establish dosage, duration of action and other factors. IAP of 0.5 micrograms/kg or 1.0 micrograms/kg did not bring about any serious toxic or adverse effects in five volunteers. On the 4th day of a single injection of IAP, insulin secretory response was proved to be enhanced. Follow-up studies showed that the IAP-action continued over a month or at most two months. Two features of IAP, i.e., the enhancement of insulin secretory response and the long duration of the action, was confirmed in healthy persons as well as in animals. As expected, IAP has a strong antigenic reaction resulting in formation of IgG antibody and possibly IgE antibody. The antigenicity of IAP causes some hindrance to clinical usefulness. For avoidance of anaphylactic reaction, IAP should be given repeatedly with care. The problem concerning antigen-antibody reaction should be overcome as soon as possible before the clinical use of IAP as a medicament.

Adult↗