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S Takechi

Publications and source records attributed to S Takechi.

31 records · Page 2Linked to original sources
PubMed1993

Presence of particular transcription regulatory elements in the 5'-intergenic region shared by the chicken H2A-III and H2B-V pair.

The two chicken histone gene families, H2A and H2B, contain nine and eight members, respectively, within two major histone gene clusters. Six genes each from families H2A and H2B have been found to be closely associated in inverted directions as H2A/H2B gene pairs. Two previously sequenced H2A members (H2A-I and H2A-II) encode the same amino acid (aa) sequence (class I), whereas seven sequenced H2B genes encode three different variants (classes I, II and III). In this study, we first sequenced H2A-III, a member of the H2A family, which is located in inverted orientation and 350 bp upstream from H2B-V, encoding the class-III H2B protein. The protein encoded by H2A-III differs from the class-I H2A protein in a single aa (Ala70-->Pro; class II). As a step toward elucidation of the transcriptional regulation of the H2A and H2B families, we fused this 5'-intergenic region to the cat gene in inverted orientations to generate two chimeric plasmids, pH2A-III-350 and pH2B-V-350. Transient CAT assays using these constructs indicated that the promoter of H2B-V is more active than that of H2A-III. CAT assays with 5'-deletion mutants of H2A-III and H2B-V showed that they each possess particular transcriptional motifs which are located relatively close to, or apart from, their own coding regions. These findings, together with those reported previously on the H2A-V/H2B-II pair, suggest distinct manners of transcription regulation of different members of the chicken histone gene families, H2A and H2B.

3T3 Cells↗
PubMed1993

Nucleotide sequence of the cDNA encoding mouse thyroid peroxidase.

The nucleotide (nt) sequence of the cDNA encoding mouse thyroid peroxidase (TPO) has been determined. The TPO cDNA is 3281 nt long and its open reading frame encodes a protein composed of 914 amino acids (aa), including a putative initiation Met. The mouse TPO cDNA shows 75.3, 70.8, and 93.5% homology in the coding nt sequence with human, porcine, and rat TPO cDNAs, respectively. In the aa sequence, mouse TPO shows 73.4, 68.4, and 93.9% homology with human, porcine, and rat TPOs, respectively. Specifically, the aa sequence surrounding the proximal His residue, probably essential for TPO activity, is well conserved among these four organisms.

Amino Acid Sequence↗
PubMed1993

The chicken histone gene family.

1. Most of the chicken 43 core and H1 histone genes belong to two major histone gene clusters. 2. Each of six H1 genes encodes a different H1 protein sequence. 3. The known core histone genes, four H2A, seven H2B, and seven H3 genes, respectively, encode two, three and three different protein variants, whereas the four known H4 genes encode the same amino acid sequence. 4. The core histone genes have particular transcription regulatory elements within the 5'-flanking regions and the regulations of their expressions are distinct, even though they are members of the same core histone gene family. 5. There are some undefined differences in the DNA structures of the particular core histone genes in various chicken tissues and these structural variations probably result in differences in their transcriptional regulation.

Animals↗
PubMed1993

[Effect of enalapril on left ventricular hypertrophy and left ventricular function in patients with hypertension].

The aim of this study was to study the effect of enalapril (E) on left ventricular (LV) mass, LV function and blood renin-angiotensin (RA) in patients with hypertension. Sixteen hypertensives were included in this study (WHO I 8, WHO II 8, 49.5 +/- 10.5 yrs). They were examined for blood pressure and heart rate. Chest X-ray film, echocardiography (echo), X-ray computed tomography (CT) and RA before and after about 6 months of E administration were studied. The LV mass was calculated by CT. The LV function was measured by echo. RAS was unchanged during this study. LV mass was significantly reduced after E (121.4 +/- 25.6 vs 104.6 +/- 13.7 g/cm2). The LV systolic function was unchanged after E, but LV diastolic function improved. It was shown that the long-term administration of E improves LV hypertrophy and LV diastolic function without any change of RAS.

Adult↗
PubMed1991

Nucleotide sequences of two members of the chicken H4 histone-encoding gene family.

The nucleotide sequences of two genes (H4-III and H4-IV) from the chicken H4 histone-encoding gene family have been determined. The four H4 genes, including the previously sequenced H4-I and H4-II genes, encode the same amino acid sequence and possess several copies of the possible Sp1-binding sequences on the coding and noncoding strands within the 5'-flanking regions.

Amino Acid Sequence↗
PubMed1990

Specific role of an alpha,beta-unsaturated carbonyl group in gamma-glutamylcysteine synthetase induction by prostaglandin A2.

The effects of prostaglandins (PGs) on cellular glutathione (GSH) status in L-1210 cells were examined. PGA2 and J2, which have an alpha,beta-unsaturated carbonyl group in the cyclopentane ring, elevated the GSH content, but PGB2, D2, E2 and F2 alpha did not show the effect. When L-1210 cells were incubated with various 2-cyclopentenone derivatives, 4-hydroxy-2-cyclopentenone and some of related compounds elevated cellular GSH levels. Subsequent study with cell-free extract of cultured L-1210 cells revealed that PGA2 and 4-hydroxy-2-cyclopentenone induced gamma-glutamycysteine synthetase activity at the transcriptional level. This induction was also found in other cultured mammalian cells such as HeLa S3, NIH/3T3 and porcine aorta endothelial cells. When L-1210 cells were incubated with PGA2 in the presence of 4-hydroxy-2-cyclopentenone and its analogues, they inhibited the accumulation of PGA2 in cell nuclei. Our findings thus suggest that an alpha,beta-unsaturated carbonyl moiety is responsible for enhancing the biosynthesis of gamma-glutamylcysteine synthetase in cultured cells.

Animals↗
PubMed1990

Cardiac acetylcholine concentration in the rat.

Varying values for the acetylcholine (ACh) concentration in the rat heart have been reported. The possibility that the method of sampling may influence prompted a comparison of heart levels of ACh obtained by two different procedures for sacrificing animals. One method was by microwave irradiation in vivo and the others being in vitro on the irradiated heart removed after decapitation. There were significant differences found in cardiac ACh concentration between the in vivo irradiated group and the decapitation groups. In decapitated animals, the cardiac ACh concentration became increasingly lower on standing. We also measured the ACh concentration of right atrium, left atrium, right ventricle and left ventricle. They were 4.62 +/- 1.57 nmol/g (mean +/- SD), 2.58 +/- 1.01, 2.76 +/- 1.00 and 2.12 +/- 0.70, respectively. We conclude the microwave irradiation in vivo is a more appropriate method for determining the cardiac ACh concentration.

Acetylcholine↗
PubMed1989

[A case of cardiac myxoma associated with congenital oculocutaneous albinism].

This case is a 43 year-old-woman of left atrial myxoma associated with oculocutaneous albinism, who was admitted to our hospital because of nocturnal cough everyday. Electrocardiogram showed normal sinus rhythm and complete right bundle branch block. Chest X-ray disclosed slight enlargement of left atrium. Echocardiography revealed the left atrial pedunculated tumor, arising from atrial septum, prolapsing into left ventricle during diastole, which was coincided with lucent tumor by levophase of pulmonary arteriography. Feeder artery of this tumor was visualized by right coronary arteriography. Cardiac catheterization represented normal pressure of right-sided heart. Thus the diagnosis of left atrial myxoma was established. At the operation, radical excision of the base of tumor and septum and patch closure was undergone. The gross morphology and microscopic findings were consistent with myxoma.

Adult↗
PubMed1988

Cardiac acetylcholine concentration in the mouse.

We measured cardiac acetylcholine (ACh) in mice using four different methods. The mice in the in vivo irradiation group received microwave irradiation and then the hearts were removed. The animals in the in vitro irradiation group were decapitated and only the hearts were irradiated. The animals in the non-frozen group were decapitated and ACh was measured soon after the removal of the heart. The animals in the frozen group were decapitated and the hearts were frozen. There were significant differences in ACh concentrations between the in vivo irradiation group and the other groups. We also measured the ACh concentrations in both atria and ventricles after the mice were irradiated while alive. The atrial ACh concentration 1.70 +/- 0.70 nmol/g (mean +/- SD) was significantly higher than the ventricle concentration 1.07 +/- 0.30. We concluded the microwave irradiation of animals was suitable method of sacrifice for the measurement of cardiac ACh.

Acetylcholine↗
PubMed1985

Direct blood pressure monitoring in patients with pheochromocytoma.

In patients with pheochromocytoma, blood pressure was monitored continuously for 2 days using direct measurement techniques. Systolic blood pressure sometimes increased to more than 300 mmHg. These sudden elevations of blood pressure were associated with increased levels of plasma catecholamines. Pre-operative prazosin and propranolol therapy lowered mean systolic and diastolic blood pressure throughout the 2 day observation periods and was associated with decreased hematocrit levels. However, these agents did not prevent the rapid elevation of blood pressure.

Adult↗