Search PubMed⌕ Search

Biomedical subjects

T Baba

Publications and source records attributed to T Baba.

At least 343 records · Page 19Linked to original sources
PubMed1992

[Electrophysiologic effect of a new Ca(2+)-antagonist, TA-3090 on supraventricular tachycardia and conduction system].

We investigated the effect of a new Ca-antagonist, TA-3090 on supraventricular tachycardia (SVT) and conduction system, comparing it with the effect of Diltiazem Hydrochloride, in 11 patients who had paroxysmal SVT attacks. Seven of the 11 patients presented atrioventricular reentrant tachycardia (AVRT) via retrograde concealed conduction through an accessory pathway, and the others presented AV nodal reentrant tachycardia (AVNRT). After SVT was induced by means of programmed electrical stimulation at high right atrium, TA-3090 (0.1 mg/kg body weight) or Diltiazem (0.2 mg/kg) was administered intravenously for 3 minutes. TA-3090 terminated nine of 11 SVTs, while Diltiazem terminated four of 4 SVTs. On termination of SVT, both drugs interrupted A-H conduction during AVRT and the slow pathway during AVNRT. After TA injection, five of 11 SVTs could not be induced by programmed electrical stimulation, while two of 4 SVTs could not be induced after Diltiazem. In AVRT, three patients in which TA-3090 prevented SVT induction had a longer AV node effective refractory period than that of the others in which TA-3090 could not prevent SVT (330 +/- 46 vs 210 +/- 24 msec, p less than 0.01). However, SVT was induced more easily than before in three of the 11 patients treated with TA-3090 administration, and in one of the 4 patients treated with Diltiazem administration.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

An antigranulomatous effect of glycyrrhizin.

In our previous study, we reported that monocyte-activation inhibitory factor was produced by stimulated fibroblasts. We also previously found that glycyrrhizin (GL) had an ability to affect fibroblasts because the proliferation of human fibroblasts was increased by GL. In this study, we demonstrated that culture supernatants from the GL-stimulated fibroblasts inhibited the activation of normal human peripheral monocytes in vitro. Then, studies were performed to know whether GL affects fibroblasts to suppress the granuloma formation. Pulmonary granulomas were induced in guinea pigs by Sephadex beads. The formation of granulomas was significantly suppressed by intraperitoneal injections of GL. Thus, GL was shown to have antigranulomatous effects in vivo.

Animals↗
PubMed1992

The antagonistic effect of interferon-beta on the interferon-gamma-induced expression of HLA-DR antigen in a squamous cell carcinoma line.

We examined the effect of type I interferon (IFN) on IFN-gamma-induced HLA-DR antigen expression in A431 cells, a human squamous cell carcinoma line. A431 cells expressed HLA-DR antigen when stimulated with IFN-gamma, but not with IFN-beta. Simultaneous addition of IFN-gamma and IFN-beta to A431 cells resulted in significantly decreased HLA-DR antigen expression when compared to treatment with IFN-gamma alone. Kinetic studies revealed that IFN-beta was required concomitantly or prior to stimulation with IFN-gamma in order to down-regulate expression of HLA-DR antigens. IFN-alpha also inhibited IFN-gamma-induced HLA-DR antigen expression in A431 cells. Analysis of cytoplasmic mRNA showed that simultaneous treatment of A431 cells with IFN-gamma and IFN-beta resulted in a marked decrease of the level of DR alpha specific mRNA when compared to a level reached after treatment with IFN-gamma alone. These results suggest that type I IFN antagonize the IFN-gamma-induced HLA-DR antigen expression in human keratinocyte system, and that this antagonistic effect of type I IFN is confirmed as evidenced by a change in HLA-DR mRNA levels.

Blotting, Northern↗
PubMed1991

Sequence conservation of the catalytic regions of amylolytic enzymes in maize branching enzyme-I.

We have identified cDNA clones encoding branching enzyme-I (BE-I) from a maize kernel cDNA library. The combined nucleotide sequence of the cDNAs indicates that maize BE-I is initially synthesized as a precursor protein with a putative 64-residue transit peptide at the amino terminus, and that the mature enzyme contains 759 amino acid residues with a calculated molecular mass of 86,236 Da. The four regions, which constitute the catalytic site of amylolytic enzymes, are conserved in the sequences of BE-I and bacterial branching enzymes. This result demonstrates that branching enzyme belongs to a family of the amylolytic enzymes. The BE-I gene is highly expressed in the early stages of kernel development, and the level of the message concentration decreases slowly as kernel maturation proceeds.

1,4-alpha-Glucan Branching Enzyme↗
PubMed1991

Therapeutic efficacy of two-route chemotherapy using cis-diamminedichloroplatinum(II) and its antidote, sodium thiosulfate, combined with the angiotensin-II-induced hypertension method in a rat uterine tumor.

To enhance the therapeutic effect of conventional TRC using intra-arterial (i.a.) DDP plus simultaneous i.v. STS, we combined the AT-II-induced hypertension method with TRC and evaluated its efficacy for a rat uterine tumor, using the simulation of intra-arterial chemotherapy for human uterine tumors. During interruption of arterial blood flow by vascular manipulations, DDP plus AT-II were injected for 10 min through the abdominal aorta in the direction of the uterus. Then STS was administered i.v. for a further 5 min and all the arterial restrictions were released. This modified TRC using AT-II showed a much higher anti-tumor effect than that seen in conventional TRC without AT-II and was free from DDP-induced renal damage. On the other hand, severe nephrotoxicity was unavoidable in the rats given the delayed i.v. administration of STS to i.a. DDP alone. The feasibility of post-administration of STS without obvious nephrotoxicity in modified TRC was explained by transient inhibition of DDP delivery to the kidney during the AT-II-induced hypertension. The loss of body weight and the decrease in the number of leukocytes after this therapy were tolerable. Modified TRC showed a higher anti-tumor effect and a lower nephrotoxicity compared with other treatments, as follows: DDP i.a. with or without AT-II; i.v. infusion of DDP alone. Such a superior anti-tumor effect of modified TRC consists of the following 2 factors: (i) the post-administration of STS leading to the delayed neutralization of DDP at the tumor site; (ii) the selective enhancement of DDP delivery to the tumor tissue during AT-II-induced hypertension.

Angiotensin II↗
PubMed1991

Structure of human milk bile salt activated lipase.

The structure and some functional sites of human milk bile salt activated lipase (BAL) were studied by cDNA cloning and chemical analysis of the enzyme. Eighteen cDNA clones of human BAL were identified from lactating human breast cDNA libraries in lambda gt11 and lambda gt10 with antibody and synthetic oligonucleotides as probes. The sequence of four clones was sufficient to construct a 3018-bp BAL cDNA structure. This sequence codes for an open reading frame of 742 amino acid residues. There is a putative signal sequence of 20 residues which is followed by the amino-terminal sequence of BAL, and the mature BAL contains 722 amino acid residues. The cDNA sequence also contains a 678-base 5'-untranslated sequence, a 97-base 3'-untranslated region, and a 14-base poly(A) tail. The sequence of a 1.8-kbp insert of clone G10-4A differs from that of the other cDNA in that it contains a deletion of 198 bases (1966-2163) corresponding to 66 amino acid residues. By use of BAL cDNA as probe, it was found that the major molecular species of BAL mRNA in human mammary gland HBL-100 cells had a size of 2.9 kb and two minor species had sizes of 3.8 and 5.1 kb by Northern blot analyses. The deduced BAL protein structure contains in the carboxyl-terminal region 16 repeating units of 11 amino acids each. The repeating units have the basic structure Pro-Val-Pro-Pro-Thr-Gly-Asp-Ser-Gly-Ala-Pro with only minor substitutions. The amino acid sequence of human BAL is related to that of pancreatic lysophospholipase, cholesterol esterase, cholinesterase, acetylcholinesterase, and thyroglobulin. Ten of the 14 cyanogen bromide fragments of diisopropyl fluorophosphate inhibited human milk BAL were isolated, determined for N-terminal sequences, analyzed for amino sugars, and tested for some functional properties. These chemical studies established that the active site of human milk BAL is located at serine-194, the N-glycosylation site is present at asparagine-187, the O-glycosylation region is in the 16 repeating units near the C-terminus, and the heparin binding domain is in the N-terminal region. We have also determined the location of disulfide bridges as Cys64-Cys80 and Cys246-Cys257. The cyanogen bromide cleavage and the partial sequencing of CNBr peptides also confirmed the location of methionines in the polypeptide chain as well as the deduced cDNA sequence of BAL.

Amino Acid Sequence↗
PubMed1991

Rapid detection of a point mutation in thyroid-stimulating hormone beta-subunit gene causing congenital isolated thyroid-stimulating hormone deficiency.

Previous study showed that congenital isolated TSH deficiency in Japan is resulted exclusively from a G-A transition at nucleotide 145 in exon 2 of the TSH beta-subunit gene. All reported cases were from the inbred in Shikoku Island. We describe here a 10-year-old boy with hereditary TSH deficiency in the same area. The patient was born with a weight of 3,225 g to non-consanguineous parents. Evaluation at age 2 months revealed typical manifestations of cretinism without goiter. Serum T4, T3, and TSH values were 2.53 micrograms/dl, 107 ng/dl, and 0.5 microU/ml, respectively. A TRH stimulation test showed no increment of serum TSH value. Other anterior pituitary hormone levels were all within the normal range. Two oligonucleotide primers T1a and T1b were synthesized according to the sequence data. Amplified 169 bp nucleotides in exon 2 of the TSH beta gene with this primer set were digested with MaeI. Both the phenotypically normal brother and normal controls showed only the 169 bp fragment, whereas the proband showed 140 and 29 bp fragments and both parents showed three fragments; 169, 140, and 29 bp. These results were consistent with the point mutation of TSH beta gene in Japanese patients with congenital isolated TSH deficiency. Our PCR method with MaeI digestion contributes to the rapid detection of the homozygous patient and the heterozygous carrier.

Child↗
PubMed1991

Three-dimensional study of the cytoskeleton in macrophages and multinucleate giant cells by quick-freezing and deep-etching method.

The three-dimensional ultrastructure of multinucleate giant cells in subcutaneous granulomas was compared with those of peritoneal macrophages using a quick-freezing and deep-etching method. Subcutaneous granulomas were induced by implanting plastic coverslips in the dorsal subcutaneous tissue of rats. The quick-freezing and deep-etching replicas were prepared from the cells attached to the coverslips. Dense networks of actin filaments were distributed along all peripheral aspects (beneath the plasma membrane, and on free and coverslip-attached surfaces) of the multinucleate giant cells. On the coverslip-attached surface, numerous clathrin-coated pits and vesicles occurred between the actin filaments. In these cells, intermediate filaments, but not actin filaments, were the predominant cytoskeletal components in perinuclear regions and were attached to the cell nucleus, mitochondria and other vesicular cell organelles. A similar distribution of cytoskeletal components was observed in the mononuclear macrophages of the granulomas and the peritoneal macrophages. These results show that the cytoskeletal organization varies in different regions of the cytoplasm of multinucleate giant cells, while the characteristic cytoskeletal arrangement, resembling that of mononuclear macrophages, is maintained.

Actins↗
PubMed1991

Intracarotid infusion of leukotriene C4 selectively increases blood-brain barrier permeability after focal ischemia in rats.

Intracarotid infusions of leukotriene C4 (LTC4) were used to open selectively the blood-brain barrier (BBB) in ischemic tissue after middle cerebral artery (MCA) occlusion in rats. BBB permeability was determined by quantitative autoradiography using [14C]aminoisobutyric acid. Seventy-two hours after MCA occlusion, LTC4 (4 micrograms total dose) infused into the carotid artery ipsilateral to the MCA occlusion selectively increased the unidirectional transfer constant for permeability Ki approximately threefold within core ischemic tissue and tissue adjacent ot the ischemic core. No effect on BBB permeability was seen within nonischemic brain tissue or in ischemic tissue after only 24 h after MCA occlusion. gamma-Glutamyl transpeptidase (gamma-GTP) activity was decreased in capillaries in ischemic tissue at 48 and 72 h after infarction, compared to high gamma-GTP in normal brain capillaries and moderate gamma-GTP in capillaries in the ischemic tissue at 24 h after infarction. These findings suggest that normal brain capillaries resist the vasogenic effects of LTC4. In contrast, LTC4 increases permeability in capillaries of ischemic tissue, where gamma-GTP is decreased. gamma-Glutamyl transpeptidase, an enzyme that inactivates LTC4 to LTD4 and LTE4 to LTF4, may act as an "enzymatic barrier" in normal brain capillaries to leukotrienes.

Animals↗
PubMed1991

Structure and organization of the mouse acrosin gene.

The genomic region carrying the mouse acrosin gene, including the 5'-flanking sequence, has been isolated and characterized. The acrosin gene consists of five exons separated by four introns. Organization of this gene is very similar to those of the genes for other typical serine proteases, except for the phase class of the first intron. Riboprobe mapping and primer extension analyses showed that the start site of transcription initiation in the acrosin gene is heterogeneous, including three major sites. Thus, the structure and organization of the mouse acrosin gene are different from those of the human gene [Keime, S., Adham, I.M., & Engel, W. (1990) Eur. J. Biochem. 190, 195-200] in two respects: the number of transcription initiation sites and the phase class of the third intron. The putative promoter regions of the mouse and human acrosin genes lack typical sequences of TATA, CAAT, and GC boxes, but contain a consensus sequence, GGGTGGG, known to be specific for the phosphoglycerate kinase-2 gene, and the protamine-1 and 2 genes that are uniquely expressed during spermatogenesis.

Acrosin↗
PubMed1991

Differentiation disorders of keratinocytes in seborrheic keratosis (acanthotic type).

Since the differential disorder of keratinocytes in seborrheic keratosis remains to be elucidated, the differentiation of seborrheic keratosis (acanthotic type) was examined immunohistochemically using a lectin and two anti-keratin monoclonal antibodies. A lectin, peanut agglutinin (PNA), and anti-keratin monoclonal antibody, 34 beta B4, recognize the whole epidermis except for the basal layer in the normal epidermis. In seborrheic keratosis (acanthotic type), cells unstained with either PNA or 34 beta B4 were found throughout the entire tumor. In the upper part of the tumor, some cells appeared to undergo keratinization without expressing the differential markers recognized by PNA or 34 beta B4. Another anti-keratin monoclonal antibody, 34 beta E12, stained the tissues in the same way as in the normal epidermis. Thus it was indicated that, in seborrheic keratosis (acanthotic type), although differentiation was partially maintained, some cells might undergo maturation without expressing the differentiation markers recognized by PNA or 34 beta B4.

Aged↗
PubMed1991

A case of neonatal McCune-Albright syndrome with Cushing syndrome and hyperthyroidism.

We describe a female newborn infant with McCune-Albright syndrome. In addition to the cutaneous pigmentation, she had apparent manifestations of hyperthyroidism and Cushing syndrome since birth. X-ray examinations showed many scattered lucencies in multiple bones. Endocrinological findings were as follows: serum T 4 276 nmol/l; free T 4 125 pmol/l; TSH less than 1 mU/l; serum cortisol greater than 2210 nmol/l; plasma ACTH less than 10 pg/ml; urinary free cortisol 865 nmol/day; estradiol 0.36 nmol/l. Regardless of treatment with antithyroid drugs and an inhibitor of 3 beta-hydroxysteroid dehydrogenase, the patient died of cardiac failure at the age of 4 months. Autopsy findings included a follicle cyst in the right ovary and multinodular hyperplasia in the thyroid and both adrenals. To our knowledge such a severe neonatal form of McCune-Albright syndrome has not been described in the literature.

Adrenal Cortex↗
PubMed1991

Hyperinsulinemia and blood pressure in non-obese middle-aged subjects with normal glucose tolerance.

A possible link between hyperinsulinemia and blood pressure was studied in non-obese subjects with normal glucose tolerance. First, the responses in plasma glucose and serum insulin to an oral glucose load (75-g oral glucose tolerance test) were compared between 42 patients with essential hypertension and 93 normotensive control subjects. Second, of the 93 normotensive subjects, the relations of serum insulin levels to blood pressure, serum cholesterol, and triglycerides concentrations were assessed in 8 hyperinsulinemic (serum insulin level [during fasting, or after glucose loading, or both] greater than 2 S.D. higher than the mean) and 8 pair-matched normoinsulinemic subjects (serum insulin level within 1 S.D. of the mean), individually matched for age, sex, and body mass index. Plasma glucose and serum insulin responses to the glucose load in hypertensive subjects were identical to the respective responses in normotensive subjects, while the mean total serum cholesterol level was slightly higher (p less than 0.05) in hypertensive subjects. The respective values for systolic and diastolic blood pressures, and total serum cholesterol and triglycerides concentrations were comparable in hyperinsulinemic and normoinsulinemic subjects. These results did not suggest a close association between hyperinsulinemia and elevated blood pressure in non-obese middle-aged Japanese subjects with normal glucose tolerance.

Blood Glucose↗