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T Hirayama

Publications and source records attributed to T Hirayama.

At least 19 recordsLinked to original sources
PubMed1992

Exon-intron organization of the Arabidopsis thaliana protein kinase genes CDC2a and CDC2b.

We have previously shown by cDNA cloning that a higher plant, Arabidopsis thaliana, possesses at least two CDC2 genes (CDC2a and CDC2b) similar to the cell-cycle-controlling cdc2 gene of Schizosaccharomyces pombe. To understand the exon-intron organization of these genes, genomic clones were isolated and their nucleotide sequences determined. The coding and 5'-untranslated regions of CDC2a were interrupted by seven and one introns, respectively, whilst CDC2b contained three introns within the coding portion. These intron positions partly overlapped with each other and with those of the yeast cdc2 gene, nevertheless the lengths and sequences of the corresponding introns were diverse.

Amino Acid Sequence↗
PubMed1992

Novel protein kinase of Arabidopsis thaliana (APK1) that phosphorylates tyrosine, serine and threonine.

During the course of characterizing polymerase chain reaction products corresponding to protein kinases of a higher plant, Arabidopsis thaliana, we found a DNA fragment that potentially codes for a polypeptide with mosaic sequences of two classes of protein kinases, a tyrosine-specific and a serine/threonine-specific one. Overlapping complementary DNA (cDNA) clones coinciding with this fragment were isolated from an A. thaliana cDNA library. From their sequence analyses a protein kinase was predicted composed of 410 amino acid residues (APK1, Arabidopsis protein kinase 1), in which the kinase domain was flanked by short non-kinase domains. Upon expression of APK1 in Escherichia coli cells, several bacterial proteins became reactive with anti-phosphotyrosine antibody but not with the same antibody preincubated with phosphotyrosine, convincing us that APK1 phosphorylated tyrosine residues. APK1 purified from an over-producing E. coli strain showed serine/threonine kinase activity, and no tyrosine kinase activity, towards APK1 itself, casein, enolase, and myosin light chains. APK1 was thus concluded to be a novel type of protein kinase, which could phosphorylate tyrosine, serine, and threonine residues, though tyrosine phosphorylation seemed to occur only on limited substrates. Since the structure of the APK1 N-terminal portion was indicative of N-myristoylation, APK1 might associate with membranes and thereby contribute to signal transduction. The A. thaliana genome contained two APK1 genes close to each other (APK1a and APK1b).

Amino Acid Sequence↗
PubMed1992

Growth of a giant aneurysm following complete thrombosis by detachable balloon occlusion.

A giant basilar artery aneurysm demonstrating growth and causing neurological deterioration even after complete detachable balloon occlusion is reported. Autopsy revealed total thrombosis of the aneurysm and a hemiconcentric, onion skin-like, laminated structure. Numerous vascular channels and multiple fresh intramural hemorrhages were noted within the outer margin of the aneurysmal wall. Repeated intramural hemorrhages appeared to have been responsible for the aneurysmal laminated structure and contributed to progressive aneurysmal growth. This case demonstrates that the growth of some giant aneurysms is not dependent upon the continuity with the parent artery, and progressive enlargement cannot always be prevented by balloon occlusion.

Basilar Artery↗
PubMed1992

Mutagenicity of the reaction products of dibenzo-p-dioxin with nitrogen oxides.

Dibenzo-p-dioxin (DD) was made to react with various concentrations of nitrogen oxides in the dark. The mutagenicities of the reaction products were tested using Salmonella typhimurium strains TA98, TA100, TA98NR and TA98/1,8-DNP6 in the presence or absence of a mammalian metabolic activation system (S9 mix). DD-NOx (molar ratios 1:3, 1:6 and 1:18) reaction products exhibited mutagenic potency in strains TA98 and TA98/1,8-DNP6 without S9 mix. In a gas chromatography/mass spectrometry study, 2-nitrodibenzo-p-dioxin (NDD) was identified with authentic sample in the mutagenic reaction products. DD-NOx (1:18) reaction products were reduced by sodium hydrogen sulfide and the reduction mixture was analyzed by HPLC. 2,7-Dinitrodibenzo-p-dioxin (DNDD) and 2,8-DNDD were identified as corresponding diamino-DDs in the reduction mixture. 2-NDD, 2,7-DNDD and 2,8-DNDD were also mutagenic in strains TA98 and TA98/1,8-DNP6 without S9 mix and the mutagenicity of DD-NOx reaction products was largely accounted for by the nitro-DDs.

Chromatography, High Pressure Liquid↗
PubMed1992

Mutagenicity of nitro derivatives produced by exposure of dibenzofuran to nitrogen oxides.

Dibenzofuran (DF) was reacted with various concentrations of nitrogen oxides (NOx) under light irradiation. The mutagenicities of the reaction mixtures were tested using Salmonella typhimurium strains TA98, TA100, TA98NR and TA98/1,8-DNP6 in the presence or absence of a mammalian metabolic activation system (S9 mix). DF-Nox (molar ratios 1:3, 1:6 and 1:18) reaction mixtures exhibited mutagenic potency in strain TA98 without S9 mix, and their direct-acting mutagenicity was reduced in strains TA98NR and TA98/1,8-DNP6. Four mononitrodibenzofurans and 2 dinitrodibenzofurans, i.e., 1-nitrodibenzofuran (NDF), 2-NDF, 3-NDF, 4-NDF, 2,7-dinitrodibenzofuran (DNDF) and 2,8-DNDF, were identified with authentic samples in the DF-NOx (1:18) reaction mixture by HPLC cochromatography and a gas chromatography/mass spectrometry study. The order of mutagenicity of nitrodibenzofurans in strain TA98 without S9 mix was as follows: 2,7-DNDF greater than 2,8-DNDF greater than 3-NDF greater than 2-NDF greater than 4-NDF greater than 1-NDF. The mutagenic potency of 2,7-DNDF in strains TA98 and TA100 was enhanced by the addition of S9 mix. Since these nitrodibenzofurans were less mutagenic in strains TA98NR and TA98/1,8-DNP6 than in strain TA98 without S9 mix, it was presumed that their mutagenicity was dependent on their activation by the 'classical' bacterial nitroreductase and/or transacetylase, which are absent in strains TA98NR and TA98/1,8-DNP6 but present in strain TA98, respectively. 3-NDF and 4-NDF were mutagenic in strain TA100 without S9 mix. 2-NDF and 3-NDF were determined as corresponding amino derivatives in DF-NOx (1:3), (1:6) and (1:18) reaction mixtures. They contributed about 30-65% of the direct-acting mutagenicity of reaction mixtures in strain TA98.

Animals↗
PubMed1992

Glycoprotein receptors for a heat-stable enterotoxin (STh) produced by enterotoxigenic Escherichia coli.

Glycoprotein receptors for heat-stable enterotoxin STh of enterotoxigenic Escherichia coli in the rat intestinal cell membrane were identified and characterized. Incubation of rat intestinal cell membranes with radioiodinated N-5-azidonitrobenzoyl-STh[5-19] (125I-ANB-STh[5-19]) followed by photolysis resulted in specific radiolabeling of two distinct proteins with M(r)s of 200,000 (designated STR-200A and STR-200B). STR-200A was found to be composed of two molecules of a protein with an M(r) of 70,000 (70-kDa protein), whereas STR-200B was composed of two different protein molecules with M(r)s of 53,000 (53-kDa protein) and 77,000 (77-kDa protein). These proteins showed no guanylate cyclase activity. The 70-kDa protein was labeled most with 125I-ANB-STh[5-19], suggesting that STR-200A is the main receptor protein in the rat intestinal cell membrane. The carbohydrate moieties of STR-200A and STR-200B were examined by enzymatic deglycosylation. The 70-kDa protein of STR-200A was found to contain N-linked high-mannose-type and/or hybrid-type oligosaccharides, and results suggested that it possesses at least three N glycosylation sites. The 53-kDa protein of STR-200B was found to have an N-linked complex-type oligosaccharide side chain. The deglycosylated 70-kDa protein retained activity for binding to STh, suggesting that the carbohydrate moieties of these receptor proteins are not important for binding with STh.

Animals↗
PubMed1992

Factors promoting embryo implantation in in vitro fertilization and embryo transfer.

The low implantation rate after embryo transfer (ET) is the most important problem to be solved in in vitro fertilization and embryo transfer (IVF-ET). Various factors which may affect embryo implantation in the endometrium have been examined. In this study, the influence of the timing of luteinization on the establishment of pregnancy was investigated. Follicle stimulation was performed by luteinizing hormone-releasing hormone agonist, human menopausal gonadotropin and human chorionic gonadotropin (hCG). hCG was injected on the day when the mean diameter of two follicles exceeded 16 mm, and 36 h after the injection the oocyte was retrieved. Progesterone (P4) supplement was started on the day of ovum retrieval (50 mg), followed by 30 mg for 14 days. The patients were divided into three groups: (1) the pregnant patients (n = 20: group Pre); (2) the nonpregnant patients without bleeding during P4 injection (n = 35; group N), and (3) the nonpregnant patients with bleeding during P4 injection (n = 30; group B). The number of follicles that developed, endometrial thickness, the day of operation, the number of oocytes harvested, the number of good quality oocytes, the number of oocytes fertilized, the number of embryos transferred, estradiol (E2) and P4 levels, and the E2/P4 ratio were examined. The endometrial thickness of group Pre (10.9 +/- 0.6 mm; mean +/- SEM) on the day of hCG injection was significantly (p less than 0.05) greater than that of groups N (9.0 +/- 0.4 mm) and B (9.2 +/- 0.3 mm).(ABSTRACT TRUNCATED AT 250 WORDS)

Buserelin↗
PubMed1992

[Spatial and quantitative analysis of the QRS and T waves by Frank-lead orthogonal electrocardiography in normal children. Comparative study in an early and late cord-clamping groups in newborns].

We studied a spatial and quantitative analysis of QRS and T waves by Frank-lead orthogonal electrocardiography (afterwards; ECG) in 50 cases of normal newborns, 30 cases of infants, 50 cases of adults, and also the variation in age was investigated. In the newborns, the comparative study was made serially, longitudinally in 21 infants with an early clamping of the cord and 29 infants with a late clamping of the cord. The results are mainly as follows. 1) The parameters reflecting the cardiac electromotive force of the right ventricle such as Sx, Qz and Sx+Qz decreased with aging. 2) Rx, i.e., the maximum leftward projection of QRS vector increased until the children, probably because the left ventricle was dominant in their growth and development and in the increased amount of work. A subsequent reduced value in the adults was considered to be mainly due to an increase of the distance between the heart and electrode by the increase in the thorax, particularly the transverse diameter and due to the growth in subcutaneous fat and muscle. 3) The values of Rx/Sx increased with aging. Rx and Sx in the adults were less than those in the children, but Rx/Sx was larger than that of Rx because Sx was less than Rx. 4) Age-related changes of Tz was most characteristic and was negative up to several days after birth. T vector was in forward direction and then turned positive (in backward). This was greatest at the period of the infants. Subsequently, it turned negative in the childhood, and extent was maximum in the adults.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1992

[A case of acute A type aortic dissection with lower extremity ischemia--percutaneous fenestration of the aortic septum followed by ascending aortic graft replacement by open distal anastomosis and retrograde cerebral perfusion].

A 56-year-old woman with severe back pain and a cold, pulseless right extremity was admitted to our hospital. Angiogram revealed a type A aortic dissection extending from ascending aorta to the aortic bifurcation with no definite re-entry point. The false lumen gave origin to the right renal artery and the right external iliac artery was occluded. Therefore, a catheter was manipulated into the true lumen through a percutaneous right femoral artery approach, and was advanced into the false lumen through the right posterolateral wall of the dissecting aortic septum. Fenestration was then performed with fully dilated angioplasty balloon across the septum. Immediately after the procedure, the patient's symptoms improved. The day after the fenestration, replacement of the ascending aorta with 24 mm woven Dacron graft was followed under the deep hypothermia and the retrograde cerebral perfusion. The patient followed a satisfactory postoperative course and postoperative angiogram showed a complete closure of the entry at the ascending aorta and adequate revascularization of the right renal and external iliac arteries.

Acute Disease↗
PubMed1992

[A case of ascending aortic dissection after aortic valve replacement in congenital bicuspid aortic valve].

Congenital bicuspid aortic valve is a risk factor of aortic dissection, but the case is rare in Japan. Several reports described ascending aortic aneurysm after aortic valve replacement. In these reports, most of aneurysms were false aneurysm, but the cases of ascending aortic dissection were rare. In this case, dissecting aneurysm of the ascending aorta occurred 4 years after aortic valve replacement, which was performed with mechanical prosthesis because of infective endocarditis, and it was repaired successfully by the modified Cabrol's method. This case was congenital bicuspid aortic valve, and had already been complicated with moderate aortic dilatation in the ascending aorta. In patients of congenital bicuspid aortic valve with aortic dilatation, consideration of complete replacement of the ascending aorta with aortic valve replacement is important.

Adult↗
PubMed1992

Comparisons of the bacterial flora in genital regions at non-pregnancy.

In the development of infectious diseases at non-pregnancy and at pregnancy, correlations between bacterial flora in the vagina and portio vaginalis and the ascending infections of those bacteria have recently been discussed. To clarify the cause of those infectious diseases, we studied the localization of microorganisms in genital regions. Patients undergone abdominal total hysterectomy (n = 172) were employed as subjects, and microorganisms isolated from 4 genital regions were studied. In addition, the preventive effect of cefmetazole (CMZ) against postoperative infections was analyzed in 479 cases including the hysterectomy cases mentioned above. The results obtained are summarized as follows: 1. The isolation rate of microorganisms at non-pregnancy, from subjects of 30 to 69 years old, was 65.6% (82/125) in the vagina and portio vaginalis, 52.1% (25/48) in the cervical mucus, 7.3% (9/124) in the uterine cavity and 0% (0/47) in the ovarian surface. 2. Numbers of microorganisms isolated in each region were 99 strains in the vagina and portio vaginalis, 28 in the cervical mucus, 10 in the uterine cavity and none in the ovarian surface. Isolation of aerobic Gram-positive bacteria (60-89.3%) and anaerobic Gram-positive bacteria (7.1-30%) were varied in each region. Lactobacillus spp. (38 strains), Staphylococcus epidermidis (20 strains) and Propionibacterium acnes (10 strains) were isolated from vagina and portio vaginalis, and Lactobacillus spp. (17 strains) were the most often isolated bacteria from the cervical mucus.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

[A successful case of thoracic aortic aneurysm with mixed cryoglobulinemia].

Cold-reactive proteins, such as cold agglutinins, cryoglobulins, and cryofibrinogens, are reversibly precipitates, or gel, upon exposure to cold temperatures. Cryoglobulins are usually not of importance, but under special conditions, such as surgical hypothermia, hyperviscosity and damage in microcirculation may occur in patients with high plasma concentration of cryoglobulins. Several groups have reported their efforts to reduce further the risks of surgical hypothermia in patients with cold agglutinins, but rarely in patients with cryoglobulins. A 57-year-old woman with thoracic aneurysm, requiring replacement of the ascending aorta and the aortic arch, had mixed cryoglobulinemia (cryocrit 29%) associated with rheumatoid arthritis. Steroids therapy and preoperative plasmapheresis were performed, and cryocrit levels were decreased until 0% before operation. Systemic hypothermia (25 degrees C), hemodilution techniques during cardiopulmonary bypass, and cold crystalloid cardioplegia were successfully employed, and no clinical evidence of microcirculation damage was posed after operation.

Aorta, Thoracic↗
PubMed1992

[A clinical assessment of efficacy in continuous retrograde cerebral perfusion method].

From November 1990 to June 1991, 8 patients underwent surgical repair using continuous retrograde cerebral perfusion (CRCP). We evaluated the effect of CRCP from these 8 cases. As a method of CRCP, we perfused with oxygenated blood from SVC canulae with a internal jugular vein pressure of 30-40 cmH2O. Simultaneously systemic perfusion from femoral arterial canulae was performed. At nasopharyngeal temperature of 15-21 degrees C, CRCP time was 46-115 minute. SVC perfusion flow was 280-900 ml/min, and femoral arterial perfusion flow was 450-1,200 ml/min. At 30 minute after starting CRCP, oxygen tension of the blood which was returned to aortic arch was 11-23 mmHg, whereas oxygen tension of the SVC perfusion blood was 210-398 mmHg. In only one patient, transient involuntary movement was seen after operation, but prolonged emergence from anesthesia was not seen. In conclusion, CRCP is considered as an useful method in the operation of the aortic arch.

Aorta, Thoracic↗
PubMed1992

[A workshop on the high risk group and the preventive oncology of renal cell carcinoma].

A workshop on the high risk group and the preventive oncology of renal cell carcinoma was held in Kyoto on September 7, 1990. The following subjects were presented: 1. Cohort study of renal cell carcinoma (Dr. Hirayama). 2. Pathoepidemiological study on the background of occurrence of renal cell carcinoma (Dr. Aoki). 3. Case-control study on renal cell carcinoma (Dr. Watanabe). 4. Geographic distribution of renal cell carcinoma in Japan (Dr. Minowa). 5. Pathological findings of small renal cell carcinoma (Prof. Yatani). 6. Pathoepidemiological study on occurrence of renal cell carcinoma (Dr. Tsuchihashi). 7. Clinical evaluation of small renal cell carcinoma (Dr. Masuda). 8. Clinical (biological) characteristics of renal cell carcinoma (Dr. Satomi). 9. Mass screening program for renal cell carcinoma on private urological clinic (Dr. Mishina). 10. Early stage detection of renal cell carcinoma (Dr. Ohe). 11. A review on the literature of epidemiology for renal cell carcinoma (Dr. Nakagawa). Possible risk factors reported for renal cell carcinoma were as follows: 1) Work in petroleum-related and dry-cleaning industries were positive risk. A predominant lifetime occupation as a professional was negative risk. 2) Milk or coffee consumption and use of artificial sweeteners were positive. Drinking of alcohol was negative. 3) Obesity was positive. 4) Personal history of cancer was positive. 5) Cigarette smoking was positive. 6) Exposure to radiation or hydrocarbon was positive. 7) Use of estrogen, diuretic and pain relievers was positive. 8) History of myocardial infarction, hypertension and diabetes mellitus was positive.

Carcinoma, Renal Cell↗
PubMed1992

[Surgical repair of distal aortic arch aneurysm using "elephant trunk" technique].

We present a surgical case of 61-year-old man with distal aortic arch aneurysm. Under selective cerebral perfusion in deep hypothermia, we approached to the aneurysm through median sternotomy. Dilated distal aortic arch and proximal descending aorta with mural thrombus in the aneurysmal lumen were found. The aortic occlusion balloon catheter was inserted into the descending aorta. A Cooley woven Dacron graft (26 mm in diameter) was anastomosed at 5 cm above its distal end loosely to the descending aorta with five interrupted mattress sutures, and the distal portion of the graft was pushed down into the distal aorta ("elephant trunk" technique). Postoperative course was uneventful and the dead space around the graft in aneurysm was filled with thrombus. Six months later, however, emergent operation was performed because of compression of the bronchus and the esophagus by enlargement of the aneurysm due to leakage. The second operation was approached through 5th left intercostal thoracotomy and median sternotomy. The aneurysm was opened, and the thrombus was amounted to 500 g. The distal end of the graft was anastomosed end-to-end to the mid-portion of the descending thoracic aorta. Postoperative course was uneventful and the patient was discharged. It is concluded that Elephant trunk technique is effective and the postoperative control of hypertension is very important.

Aorta, Thoracic↗
PubMed1992

[Classification of congenitally bicuspid aortic valve and its angiographic and surgical significance].

From January, 1978 to December, 1990, 85 patients with congenital bicuspid aortic valve underwent aortic valve replacements (AVR) with St. Jude Medical valve prosthesis. We classified congenital bicuspid aortic valve into four types. Type I (44.7%): Two cusps are situated right and left, a coronary artery arises from each related sinus of valsalva. Type II (22.4%): Type I + raphe in the right cusp. Type III (3.5%): one cusp is located anteriorly, the other posteriorly and both coronary arteries arise from anterior cusp. Type IV (29.4%): Type III + raphe in the anterior cusp. Regarding to preoperative diagnosis, aortic stenosis dominated in Type I (78.8%) and aortic regurgitation dominated in Type IV (72.0%). Implanted valve sizes were 22.2 +/- 1.8 (Type I), 23.4 +/- 1.6 (Type II) and 24.0 +/- 2.2 (Type IV). There was a significant difference between Type I and Type II, same as Type I and Type IV. Babb's method and outflow measurement method were utilized to predict the aortic annular size. However, both of them were not reliable for estimating the size of the aortic annulus in cases of aortic stenosis undergoing AVR with a 21 mm prosthesis.

Adolescent↗