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Biomedical subjects

Y Iwata

Publications and source records attributed to Y Iwata.

At least 253 records · Page 14Linked to original sources
PubMed1983

Effect of the calcium blocker, lanthanum, on bovine aortic smooth muscle cells in culture.

Smooth muscle cells harvested from fetal bovine aortic media were grown in subculture in Waymouth medium containing 10% fetal bovine serum for 14 days. Lanthanum (La3+), an inorganic Ca2+- blocker, was added in a concentration of 10(-3) M to the medium. The cultured smooth muscle cells showed short-spindle-shaped or polygonal endothelial cell-like forms, keeping a monolayer of paving-stone pattern and reached the stationary phase. They stayed in a monolayer state until the end of the 14-day culture. By fluorescent staining with FITC-labelled anti-factor VIII serum, the presence of factor VIII antigen, which is regarded as characteristic of endothelial cells in general, was demonstrated. When the medium was changed to the medium not containing La3+, the usual state of smooth muscle cells showing spindle-shaped multilayer proliferation was recovered, therefore demonstrating that this change is reversible.

Animals↗
PubMed1983

Adult T-cell leukemia on the east coast of Kii Peninsula--presentation of an anti-ATLA-negative case.

Nineteen patients with adult T-cell leukemia (ATL) have been found in the last seven years along the east coast of Kii Peninsula in Japan. The leukemic cells were of the immunologically inducer/helper T-cell phenotype. The prognosis was very poor (median survival time, 85 days), and most of the patients had fatal complications of pulmonary infections. Antibody against ATL-associated antigen (anti-ATLA) was detected in sera from 9 of 10 patients who were born along the coast. However, it was not detected in one patient who was born in a district surrounded by mountains. Although he had neither superficial lymphadenopathy nor skin lesions, he showed rapid clinical deterioration. His leukemic cells appeared to be extremely bizarre with marked nuclear deformation compared with those of the other patients. In surface marker studies the leukemic cells reacted positively with OKT3, OKT4 and OKIa-1 monoclonal antibodies. The characteristics of the anti-ATLA-negative case are discussed in comparison with the other ATL cases.

Adult↗
PubMed1983

[Clinical experience with cefoxitin in infections associated with hematopoietic disorders].

Ten inpatients at the Second Department of Internal Medicine, Mie University Hospital, developed infections in the course of treatment for hematopoietic disorders and were administered cefoxitin (CFX). Patients suffered from the following infections: pharyngitis, 2; bronchitis, 2; pneumonia, 2; sepsis, 2; bacteremia, 1; suspected cases of bacteremia, 2; and fever of unknown origin, 1. The number of infections totaled 12 as 1 patient with pharyngitis also developed sepsis and 1 patient with pneumonia developed bacteremia. Duration for the administration of CFX ranged between 5 and 18 days with a total dosage of between 30 and 108 g. Of the 10 patients treated with CFX, 9 were treated concomitantly with micronomicin (MCR), doxycycline (DOXY), or sulbenicillin (SBPC), some were treated concomitantly with only 1 of the drugs and some were treated concomitantly with 2 of the drugs. The following clinical results were obtained: Following treatment, 4 patients were considered "excellent", 5, "good", and 3, "poor". Clinical efficacy rate was 75%. Four strains of Gram-positive cocci (1 strain of S. aureus, 2 strains of S. epidermidis and 1 strain of Streptococcus sp.) and 3 strains of Gram-negative rods (2 strains of P. aeruginosa and 1 strain of E. cloacae) were found in the clinical specimens of the 10 patients. These results differed somewhat from reported data that Gram-negative rods such as E. coli, Klebsiella sp., Pseudomonas sp., Serratia sp., are dominant. No serious side effects requiring cessation of treatment were observed. Elevations in the levels of S-GOT, S-GPT, serum alkaline phosphatase, blood urea nitrogen, etc. were observed.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1983

[Fundamental and clinical studies on T-1982 (cefbuperazone) in the field of obstetrics and gynecology].

Fundamental and clinical studies were made on T-1982 (cefbuperazone) and the results were obtained as follows. Serum and uterine tissue concentrations of T-1982 were determined at 26 minutes before and at 20 to 80 minutes after the completion of intravenous drip infusion of 1 g. The levels of T-1982 in the fallopian tube, ovarium, endometrium, myometrium and uterine cervix were 23.7, 19.5, 50.5, 10.9 micrograms/g and 17.5 micrograms/g at 20 minutes after the completion of infusion. The levels were sufficiently effective against major pathogens (Gram negative bacteria and anaerobic bacilli) isolated in the field of obstetrics and gynecology. T-1982 was administered to 11 patients, including 7 of acute adnexitis, each one of pelveoperitonitis, pyometra, puerperal fever, and 1 of puerperal fever with sepsis, at a dose of 1-2 g twice a day for a period of 5 to 9 days by intravenous injection or intravenous drip infusion. Clinical responses were excellent in 5, good in 3 and poor in 3. No adverse reactions nor marked changes in laboratory findings were observed in any of the cases treated with T-1982.

Adolescent↗
PubMed1982

Computed tomography of malignant tumors of the nasal cavity and paranasal sinuses.

Staging of malignant tumors of the nasal cavity and paranasal sinuses by computed tomography (CT) was studied in a total of 49 patients, 33 with squamous cell carcinoma and 16 with tumors of other histologic types. Involved sites by the tumor were studied, and clinical staging was made using CT findings alone according to AJC classification for maxillary sinus tumors. Surgical findings for comparison were available for most cases. Of 33 squamous cell carcinomas and of 16 tumors with other histologic types, the maxillary sinus was the site of origin in 29 and eight, respectively. Of these 37 maxillary sinus tumors, 11 were staged T3, 26, T4, and none was staged T1 or T2. None of these tumors were down staged, and one T3 was upstaged after surgical procedures, although all sinuses were not explored in some cases. Sinusitis due to obstruction was indistinguishable from the tumor without bone destruction. And the determination of the site of origin was difficult in some cases. Despite these, CT should be used for pretreatment evaluation of the tumors of these sites.

Adenocarcinoma↗
PubMed1982

[Fundamental and clinical studies on piperacillin in the field of obstetrics and gynecology].

Fundamental and clinical studies were made on piperacillin (PIPC) and the results were obtained as follows. Serum and uterine tissue concentrations of PIPC were obtained from 36 to 215 minutes after intravenous single shot of 2 g of PIPC. The cervix uteri, endometrium and corpus uteri showed the highest antibiotic levels of 38.0, 43.0 and 33.0 mcg/g, respectively, at 65 minutes after injection, and oviduct and ovary showed the highest level of 31.5 and 28.5 mcg/g at 36 minutes. Its concentrations were sufficiently effective against the major pathogens (Gram-negative bacilli and anaerobes) demonstrated in the field of obstetrics and gynecology. PIPC was administered 6 patients, including 3 of pelvic peritonitis (isolated organism was E. coli 1), 2 of acute endometritis (Klebsiella sp. 1, Peptococcus sp. + Bacteroides sp. 1) and 1 of acute adnexitis, in a dosage of 1 or 2 g twice or 3 times a day for a period of 5 to 8 days by intravenous administration or intravenous drip infusion. Clinical response was obtained excellent in 1 and good in 5. No adverse reaction as observed in any of the cases treated with PIPC, nor was there any marked changes in the laboratory findings.

Adult↗
PubMed1982

Allosteric inhibition by aphidicolin of the activity of DNA polymerase alpha from mouse myeloma.

The mechanism of inhibition by aphidicolin of the activity of purified DNA polymerase alpha was studied. In the presence of aphidicolin and activated DNA, DNA polymerase alpha from mouse myeloma did not show Michaelis kinetics with respect to changes in nucleotide substrate concentration (i.e., dGTP & dTTP). A plot of the reaction velocity versus dGTP or dTTP concentration was hyperbolic with an intermediary plateau. The double reciprocal plot was concave downwards, and the Hill plot gave Hill coefficients of less than 1.0 over most of the curve. These results indicate that aphidicolin acts as an allosteric inhibitor for DNA polymerase alpha and that DNA polymerase alpha functions as a multisite enzyme that exhibits negative cooperativity among at least 3 binding sites of the nucleotide substrates (dGTP & dTTP).

Animals↗
PubMed1982

Inhibitory effects of diadenosine polyphosphates and diguanosine polyphosphates on terminal deoxynucleotidyltransferase from calf thymus.

The effects of diadenosine 5', 5"'-polyphosphates (ApnA's, n = 2-6) and diguanosine 5', 5-polyphosphates (GpnG's, n = 2-6) on the activity of terminal deoxynucleotidyltransferase (TdT) from calf thymus were investigated. Both ApnA's and GpnG's (n greater than or equal to 3) were found to inhibit TdT activity. The inhibitory effects were the strongest when TdT activity was measured by determining the incorporation of dCTP. The inhibition by ApnA's and GpnG's was due to competition with the substrate deoxynucleoside triphosphate(s). The inhibition constant (Ki) varied depending on the triphosphate substrate used, but in most cases Ki value decreased by increasing the number of the phosphoryl group of the dinucleotide inhibitors.

Adenine Nucleotides↗
PubMed1981

Antigenicity of desamido-insulin and monocomponent insulin.

No consensus about the antigenicity of monocomponent insulin has yet been reached. We have therefore administered different insulin preparations to rabbits and rats to determine IgG and IgE antibody production. The preparations used were porcine monocomponent insulin, conventional bovine and porcine insulin powders, porcine b-component and synthesized porcine mono-desamido-insulin and hexa-desamido-insulin. In rabbits, porcine b-component was the most antigenic preparation, followed by conventional bovine and porcine insulins. No antibody production was observed with the other preparations. In rats the 60 h passive cutaneous anaphylaxis test showed virtually no insulin IgE antibody production in response to porcine monocomponent insulin. However, if porcine b-component or porcine hexa-desamido-insulin was employed both for sensitisation and as the challenging antigen, positive skin reactions were observed with demonstration of insulin IgE antibodies. Our results confirm the low antigenicity of the pharmaceutical preparation of porcine monocomponent insulin and suggest that porcine hexa-desamido-insulin and porcine b-component administration may result in the production of reagin-type antibodies.

Amino Acids↗
PubMed1981

Ultrasonic Doppler studies after superficial temporal-middle cerebral artery anastomosis.

The ultrasonic Doppler technique was applied to evaluate the effect of STA-MCA anastomosis. Not only the STA itself, but also ophthalmic and major aortocranial arteries were recorded by the Doppler technique in 12 patients who had undergone STA-MCA anastomosis for internal carotid artery occlusion or stenosis. The examination was performed before, and within a month after the operation. The blood flow pattern of the STA, which had had an external carotid flow pattern, was altered to an internal carotid flow pattern by the STA-MCA bypass operation. The findings of Doppler sonograms of the STA were exactly consistent with post-operative angiograms and precisely represented the bypass patency. Among 7 patients with reverse flow direction in the ophthalmic artery before the operation, the reverse flow had decreased in 5 patients post-operatively. But no remarkable change in the ophthalmic artery was detected in the remaining 2 patients. The blood flow velocity patterns of major aortocranial arteries showed no change post-operatively.

Blood Flow Velocity↗
PubMed1981

Counter measures against death from arrhythmias in acute myocardial infarction: mortality of the disease in a hospital at different periods with changing care systems. Factors of delay in the pre-hospital phase.

The results of treatment of 400 patients with established acute myocardial infarction in a hospital at different periods with changing care systems are described. Significant reduction of death from arrhythmias could be obtained only when an organization with immediate availability of well-trained medical personnel and reliable actual continuous monitoring of electrocardiograms had been established. Components of delay in the pre-hospital phase of acute myocardial infarction were also studied. There were two significant factors in delay: one was delay due to ignorance of patients about the disease, second was the delay after consultation of family doctors until arrival at the CCU. Time is consumed in the latter factor mainly in making of definite diagnosis. The implication of these data in the management of patients with a diagnosis of acute myocardial infarction are discussed.

Arrhythmias, Cardiac↗