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Biomedical subjects

T Kamiya

Publications and source records attributed to T Kamiya.

At least 289 records · Page 16Linked to original sources
PubMed1988

Purification and properties of a specific primase-stimulating factor of bovine thymus.

The DNA replicase activity of the complex between bovine thymus DNA polymerase alpha and RNA primase was markedly decreased after the purification by ssDNA-cellulose column chromatography. In an attempt to restore the activity by supplementing some fractions eliminated from the purified enzyme, we found that a fraction eluted from the column by increasing salt concentration and 30% ammonium sulfate precipitates of the phosphocellulose-step enzyme possessed a high ability to restore the replicase activity. Thus, the factors were purified to near homogeneity from the two sources and the properties were examined. Both factors were heat-labile and trypsin-sensitive, possessed a native molecular mass of approximately 150-200 kDa as judged by Sephacryl S-200 column chromatography, and were composed of two polypeptides of 146 kDa and 47 kDa on SDS/polyacrylamide gel electrophoresis, indicating that they were an identical protein. The factor, which did not show any DNA polymerase or primase activities by itself, stimulated approximately 20-fold the replicase activity of purified DNA-polymerase-alpha-primase at a very low concentration (10 ng/50 microliter). The factor did not affect the deoxyribonucleotide polymerizing activity of the enzyme complex at all, but specifically stimulated the primase activity only. Thus, we designated the factor as primase-stimulating factor. Although varying the template concentration did not significantly affect the mode of stimulation, increasing the concentration of substrate for primer synthesis (ATP) markedly decreased the extent of stimulation. Thus, the stimulating factor seems to decrease the substrate concentration required for the primase reaction as well as increasing threefold the maximum activity attained by varying the substrate concentration. So far, no ATPase activity has been detected in the factor.

Animals↗
PubMed1988

Tricuspid and mitral regurgitation detected by color flow Doppler in the acute phase of Kawasaki disease.

Valvular lesions in the acute phase of Kawasaki disease were studied in 19 children. The patients were intensively observed by color flow Doppler every day from the day of hospitalization up to 12 days after the onset of the disease and 2 or more times a week thereafter, for up to 28 days. Mitral regurgitation (MR) was found in 9 patients (47%) and tricuspid regurgitation (TR) in 10 (53%). MRs were of transient type and confirmed from 7.5 +/- 1.6 (mean +/- standard deviation) to 13.1 +/- 6.5 days after the onset of the disease. Both types of valvular regurgitation were mild. The direction of regurgitation was from the center of valvular coaptation toward the posterior wall of the atrium. Neither valvular prolapse nor valvular deformity was noted. In patients with MR, left ventricular ejection fraction on M-mode echocardiography was significantly lower in the acute phase than in the convalescent phase of the disease (p less than 0.05). Using gallium-67 scintigram, the positive uptake of the isotope was noted in 7 (88%) of 8 patients with MR, but not found at all in 8 patients free of MR. These results suggest that MR and TR are often transient in the acute phase of Kawasaki disease and could be attributed to myocarditis.

Acute Disease↗
PubMed1988

An ovarian Sertoli-Leydig cell tumor with heterologous mucinous gland and NSE-immunoreactive-cell.

A rare case of ovarian Sertoli-Leydig cell tumor with heterologous mucinous glands and tiny carcinoid-like foci in a 33-year-old female is reported. In addition to these heterologous elements, peculiar cells, which were oval, eosinophilic and neuron-specific enolase (NSE)-positive, were also observed and had not been described previously. These NSE-immuno-reactive cells were different from argentaffin cells observed in mucinous glands and carcinoid-like foci, and seemed to play a significant role in the appearance of the heterologous mucinous gland. The nature of this peculiar NSE-immunoreactive cell is discussed.

Adult↗
PubMed1988

Myocardial ischemia in Kawasaki disease: follow-up study by cardiac catheterization and coronary angiography.

The clinical course of ischemic heart disease due to Kawasaki disease was analyzed. The subjects (children aged two months to eight years) were divided into two groups. Group 1 (n = 23) consisted of children who had sustained myocardial infarction (MI) and group 2 (n = 13) of those without clinical symptoms or signs of MI, but in whom signs of an obstructive lesion had appeared on coronary arteriography during the follow-up period. Changes in the left ventricular ejection fraction (LVEF) and the appearance of coronary arterial lesions on first and second angiography were analyzed in the two groups. It was found that (a) LVEF (51.4 +/- 13.4%, mean +/- SD) at the first study, obtained after MI in group 1, was significantly lower than that (64.3 +/- 3.7%) at the second one in group 2, which revealed recently developed obstructive lesions; (b) there was no significant difference between the two groups as to the severity of stenotic lesions on coronary arteriography; and (c) comparison of LVEF at the first angiography with that at the second study showed significant improvement in group 1 (1st, 54.2 +/- 12.0%; and 2nd, 60.8 +/- 9.7%) and significant depression in group 2 (1st, 68.1 +/- 4.4%; and 2nd, 64.3 +/- 3.7%).

Cardiac Catheterization↗
PubMed1988

Cytoplasmic factors involved in erythroid differentiation in mouse erythroleukemia (MEL) cells.

In order to identify and characterize intracellular factors involved in in vitro differentiation of mouse erythroleukemia (MEL) cells, the differentiation process was analyzed by cell and cytoplast fusion. The results suggested that the process is not a single cascade of molecular chain reactions, but a synergistic result of two different inducible intracellular reactions. One reaction is induced following damage to DNA (inhibition of DNA replication) and is not specific to MEL cells. The other reaction, which is specific to MEL cells, is fully induced by typical erythroid inducing agents such as dimethylsulfoxide or hexamethylenebisacetamide even at concentrations suboptimal for the erythroid induction. Based upon these data, we searched for the putative trans-acting differentiation-inducing factors and detected two proteinaceous factors (DIF-I and DIF-II) in the cytosol fraction which apparently correspond to these reactions. When, partially purified, either one of these factors was introduced into undifferentiated MEL cells, it triggered erythroid differentiation, provided that the recipient cells had been potentiated by the induction of the other reaction. In this article, we summarize the basic characteristics of these cytoplasmic factors involved in erythroid differentiation in MEL cells.

Animals↗
PubMed1988

Comparison of ionic and nonionic low-osmolar contrast media in coronary arteriography. A crossover study in children.

Twenty-six patients with Kawasaki disease were observed in a prospective crossover study to compare coronary arteriography with a nonionic low-osmolar contrast medium, iopamidol 370 mgI/mL, and with an ionic low-osmolar contrast medium, ioxaglate 320 mgI/mL. A slight heart rate change and no severe arrhythmia during coronary arteriography were observed with both agents. Electrocardiographically, QTc elongation and ST-T changes were marked in ioxaglate and minimal in iopamidol. No ventricular fibrillation occurred with either agent. Both contrast media provided adequate visualization for the diagnosis of Kawasaki disease, but the contrast of the images and the visualization of details were better with iopamidol than with ioxaglate. Iopamidol seems to be superior to ioxaglate in pediatric coronary arteriography.

Angiography↗
PubMed1988

Screening of blood donors for antibody to human immunodeficiency virus type I by sensitive particle agglutination assay.

A particle agglutination (PA) assay for antibody to human immunodeficiency virus type I (anti-HIV) was used to screen blood donors and to test leukemia and hemophilia patients. Results by PA showed complete agreement with the results of two kinds of enzyme immunoassay (EIA), and the false-positive rate was the same as or lower than with the EIAs. The sensitivity of PA was 10- to 100-fold higher than that of the EIAs. This simple sensitive assay takes less time and fewer personnel than the EIAs, and has been used for massive screening of blood donors in our blood center.

Adolescent↗
PubMed1988

New closed system using a sterile connection device and preconnected PRP pack for extended storage of apheresis platelet products.

In order to prevent bacterial contamination during the procedure of plateletapheresis, preconnected platelet-rich plasma (PRP) packs were prepared which include the apheresis bowl of a plasma collecting system (Haemonetics) with a 16G needle and a 0.6- and 1-liter double-bag system. The anticoagulant line of the PRP pack and that from the bag containing acid-citrate-dextrose formula A solution were welded by a sterile connection device (SCD model 312, DuPont). No additional care was needed to perform plateletapheresis with the present closed system. Platelet concentrates (PCs) stored in 1-liter bags made of polyvinyl chloride plastics with a plasticizer of either di (2-ethylhexyl) phthalate or tri (2-ethylhexyl) trimellitate were demonstrated to be sterile. The pH of PCs was maintained over 6.8 after 5-day storage. Preliminary studies suggest that the present closed system using the preconnected PRP pack and sterile connection device will be useful for reducing the risk of bacterial contamination in platelet products during single-donor plateletapheresis.

Blood Component Removal↗
PubMed1988

[Studies on the clinical significance concerning the changes in serum pepsinogen-I and gastrin levels in aged patients with chronic gastritis].

Of 86 cases of aged patients with chronic gastritis treated with Trimebutine or Flutazolam, we evaluated the changes of serum pepsinogen-I and gastrin levels in their clinical courses from the points of the correlation with severity of chronic gastritis, aging phenomenon and the changes of symptom and endoscopic findings. In order to elucidate the multidimensional interrelation among these items, we used Hayashi's quantification theory II as a conventional analysis method. In aged patients, generally, although the serum gastrin levels were rather high compared with younger generation, the serum pepsinogen-I levels were consistently low throughout their clinical courses. There were some correlation between the levels of serum gastrin and the severity of chronic gastritis. When the drugs were effective on improving the condition of the disease, the level of gastrin revealed gradual decrease. These changes of gastrin were more typical in patients treated with Trimebutine.

Aged↗
PubMed1988

Carrier detection in Japanese hemophilia A by use of three intragenic and two extragenic factor VIII DNA probes: a study of 24 kindreds.

The three factor VIII intragenic restriction fragment length polymorphisms (RFLPs), Bcll, Xbal, and Bgll and the two extragenic RFLPs, Bglll/DX13 and Taql/St14, were analyzed in 60 normal Japanese subjects and 24 families with hemophilia A. The allele frequencies were determined and the extent of linkage disequilibrium among the polymorphisms was assessed. In contrast to intragenic RFLPs of the factor IX gene, intragenic and extragenic RFLPs of the factor VIII gene in Japanese were similar to those observed in whites. As in whites, marked linkage disequilibrium severely compromised the value of the Bgll RFLP. The combination of the Bcll, Xbal, and Taql/St14 RFLPs gave 100% carrier detection in the hemophilia A families analyzed.

Asian People↗
PubMed1988

[2 surgically treated cases of adrenocortical carcinoma producing steroid hormones without endocrinological symptoms--case report and a review of cases in the Japanese literature].

We have experienced two male cases of an adrenocortical carcinoma that have produced steroid hormones without endocrinological symptoms. Both men were admitted to hospital because of an abdominal pain and left hypochondral tumors. In each case, an abdominal CT, an ultrasonogram and an angiogram demonstrated a left adrenal tumor, and levels of blood dehydroepiandrosterone sulfate, etiocholanolone, pregnenolone sulfate and urine 17 KS were elevated. The tumors were resected and the histology revealed that they were adrenocortical carcinomas. Postoperatively, the levels of their urine hormones returned to normal values, though in one man recurrence occurred a year later. Only 8 cases of an adrenocortical carcinoma that has produced steroids without specific endocrinological symptoms have been reported in Japan, and we also report on two cases herein.

17-Ketosteroids↗