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Biomedical subjects

M Hattori

Publications and source records attributed to M Hattori.

At least 19 recordsLinked to original sources
PubMed1992

Differences in direction-dependent shortening of the left ventricular wall in hypertrophic cardiomyopathy and in systemic hypertension.

To determine whether patients with hypertrophic cardiomyopathy (HC) have an altered mode of contraction of the left ventricular (LV) wall related to underlying myocardial abnormalities, geometric changes in the LV wall were analyzed at 2 points of the cardiac cycle (end-diastole and end-systole) using 2-dimensional echocardiography. The relations between meridional and circumferential shortening of the LV midwall, mean wall thickening, and the changes in the short-axis cross-sectional area of the LV wall at the level of chordae tendineae were determined in 18 patients with nonobstructive HC, and were compared with those in 31 normal subjects and 19 patients with essential systemic hypertension. In normal subjects, no significant difference was observed between meridional (16.3 +/- 2.4%) and circumferential (17.1 +/- 4.0%) shortening, whereas cross-sectional LV wall area increased significantly at end-systole (p < 0.001). In patients with hypertension, all measured indexes were not different from those in normal subjects. In contrast, patients with HC had significantly reduced meridional shortening (p < 0.001) and mean wall thickening (p < 0.01). Consequently, a striking difference was observed between meridional (8.9 +/- 2.4%) and circumferential (16.9 +/- 3.2%) shortening (p < 0.001). Furthermore, no increase in cross-sectional LV wall area was observed at end-systole. Thus, echocardiographic detection of direction-dependent contraction can be a useful index for distinguishing HC from systemic hypertension.

Adult↗
PubMed1992

Enhancement of ganglioside GM3 synthesis in okadaic-acid-treated granulosa cells.

Okadaic acid is a potent inhibitor of type-2A (PP2A) and type-1 (PP1) protein phosphatases and has been proved to be a valuable tool for studies on the protein phosphorylation. We have investigated the effects of okadaic acid on rat granulosa cells in order to determine whether the regulation of ganglioside synthesis involves protein phosphorylation via inhibition of PP2A and PP1. Granulosa cells expressed luteinizing hormone (LH) receptors, measured as the binding of 125I-deglycosylated human chorionic gonadotropin (hCG) to intact cells, and synthesized the gangliosides NeuAc alpha 2-->3Gal beta 1-->4Glc beta 1-->1Cer (GM3) and Gal beta 1-->3GalNAc beta 1-->4[NeuAc alpha 2-->3]Gal beta 1-->4Glc beta 1-->1Cer (GM1), demonstrated by metabolic labeling of glycosphingolipids with [3H]galactose, in response to follicle-stimulating hormone (FSH). When FSH-stimulated granulosa cells were treated with 10 nM okadaic acid for 15 h, down-regulation of LH receptors, dissociation of LH receptor-effector coupling and significant decreases of intracellular and extracellular 3',5'-cyclic adenosine monophosphate (cAMP) levels were observed. The okadaic acid-induced desensitization to gonadotropin in granulosa cells was accompanied by increased ganglioside synthesis. The amount of 3H-labeled ganglioside GM3, the major ganglioside (about 95% of the total) synthesized by mature granulosa cells, was enhanced in okadaic acid-desensitized cells (to 215% of the control value) and in those desensitized by hCG (by 354%), forskolin (by 190%) and 12-O-tetradecanoylphorbol 13-acetate (by 143%). The results of this study suggest that an increase in the phosphorylation state of cells is accompanied by enhancement of ganglioside synthesis.

Animals↗
PubMed1992

Unusually high conservation of untranslated sequences in cDNAs for Trimeresurus flavoviridis phospholipase A2 isozymes.

As a step toward understanding the structure and function of phospholipases A2 (PLA2s), we isolated and sequenced several cDNAs encoding Trimeresurus flavoviridis venom PLA2 isozymes including two [Lys49]PLA2s called basic proteins I and II, [Thr37]PLA2, and PLX'-PLA2. Comparison of the nucleotide sequences of these cDNAs with the previously isolated [Asp49]PLA2 cDNA revealed some interesting findings from the viewpoint of evolution. First, the homologies of the 5' and 3' untranslated regions (98% and 89%, respectively) were much higher than that of the protein-coding regions (67%). The predicted secondary structure showed the characteristic stem-loop structures for both the untranslated regions of the mRNAs, suggesting that these regions play some functional role(s) in translation or stability of mRNAs. Second, base substitutions appeared to have occurred at similar rates for the three positions of codons among these PLA2s. The results are discussed in terms of evolution of PLA2s. Northern blot analysis showed that these PLA2s are specific to venom gland.

Amino Acid Sequence↗
PubMed1992

CD3+4-8- alpha beta T cell population with biased T cell receptor V gene usage. Presence in bone marrow and possible involvement of IL-3 for their extrathymic development.

Analysis of TCR of a series of CD4-8- (double negative; DN) alpha beta T cell lines induced with IL-3 revealed that their V gene usage was biased for V alpha 4 and V beta 2. This has been confirmed in the primary short-term cultures. Thus, IL-3 induced the generation of DN alpha beta T cells with predominant V beta 2 gene expression from the CD4+/CD8+ T cell-depleted spleen or bone marrow (BM) cells of both normal and nude BALB/c mice within 10 days. It was further indicated that the V beta 2+ beta-chain genes contained few junctional N regions in both IL-3-induced primary DN alpha beta T cells and continuous lines. Search for the in vivo counterpart of in vitro IL-3-induced DN alpha beta T cells revealed that BM, but not spleens, of normal BALB/c and B6 mice did contain a significant proportion of DN alpha beta T cells, and that the majority of them expressed V beta 2+ beta-chain genes with few junctional N regions. The presence of V beta 2+ DN alpha beta T cells was similarly observed in the BM of BALB/c nude mice, but their proportion varied markedly among various strains of mice, which was not linked to H-2 haplotypes. The results indicated that V beta 2+ DN alpha beta T cells in the BM represented one of the thymus-independent T cell populations, whose development was under the major histocompatibility Ag complex-unlinked genetic control. TCR of these T cells were shown to be functional as judged by the proliferative response to anti-V beta 2 antibody. Taken together, present results suggested that IL-3 could induce differentiation and/or proliferation of DN alpha beta T cells with uniquely limited repertoire, which existed preferentially in BM in vivo, and implied the possible involvement of extrathymic endogenous ligands as a positive selection force.

Animals↗
PubMed1992

Identification of an internal cis-element essential for the human L1 transcription and a nuclear factor(s) binding to the element.

L1 (LINE-1) is a long interspersed repetitive sequence derived from a retrotransposon. Transfection studies using the CAT gene as a reporter demonstrated that the first 155bp in the human L1 sequence contains an element(s) responsible for the promoter activity in HeLa cells. The transcription was shown to initiate at the first nucleotide of the L1 sequence in the transgene. Three prominent nuclear protein binding sites were found in the 5' region of the L1 sequence by DNaseI footprint analysis. One of the binding sites, designated as site A located at +3 to +26, was shown to be essential for the L1 transcription because the mutation at the site A caused almost complete loss of the promoter activity. A sequence AAGATGGCC at +11 to +19 in the site A was defined as a target core element for the protein binding. The site A-binding protein (designated TFL1-A) was found in various types of cells including an embryonic teratocarcinoma cell line. These results indicate that an internal short element located at the very 5' terminal of L1 sequence and the nuclear factor binding to the element play a crucial role in the transcription of human L1.

Amino Acid Sequence↗
PubMed1992

Assignment of Bacillus thermoamyloliquefaciens KP1071 alpha-glucosidase I to an exo-alpha-1,4-glucosidase, and its striking similarity to bacillary oligo-1,6-glucosidases in N-terminal sequence and in structural parameters calculated from the amino acid composition.

alpha-Glucosidase I of Bacillus thermoamyloliquefaciens KP1071 (FERM P8477, facultative thermophile) was purified to homogeneity. The relative molecular mass was estimated to be 62,000 Da. From its catalytic properties, the enzyme has been assigned to an exo-alpha-1,4-glucosidase. The enzyme shares its antigenic groups in part with Bacillus stearothermophilus ATCC12016 (obligate thermophile) exo-alpha-1,4-glucosidase. These exo-alpha-1,4-glucosidases strikingly resemble oligo-1,6-glucosidases from B. thermoamyloliquefaciens KP1071 and from Bacillus cereus ATCC7064 in the molecular properties tested, including relative molecular mass, N-terminal sequence of 15 residues, amino acid composition and structural parameters calculated from amino acid composition. We have suggested that bacillary exo-alpha-1,4-glucosidases take the same folded conformation, i.e. an (alpha/beta)8-barrel super-secondary structure in its N-terminal domain, as bacillary oligo-1,6-glucosidases.

Amino Acid Sequence↗
PubMed1992

Positive and negative regulatory elements for the expression of the Alzheimer's disease amyloid precursor-encoding gene in mouse.

We cloned, sequenced and characterized a promoter region of the mouse homologue of the Alzheimer's disease amyloid precursor protein (APP)-encoding gene. The promoter region is highly homologous to that of the human APP (hAPP) gene. It has a high G+C content, lacks typical 'TATA' and 'CAAT' boxes, and contains possible binding sites for AP-1, heat-shock factor, Sp1 and AP-4. The promoter region was fused with the cat reporter gene, and the fusion genes were transfected to both the NB41A3 (mouse neuroblastoma) and L-cell lines. The promoter activity was monitored by chloramphenicol acetyltransferase (CAT) activity in a transient expression assay. The promoter was equally active in both cell lines. The deletion analysis revealed that there existed a negative regulatory element(s) between -153 and -100 bp and a positive element(s) between -100 and -37 bp. The negative element was shown to suppress the transcriptional activity of heterologous simian virus 40 promoter. DNase I footprinting experiments revealed that three nuclear protein-binding sites existed in the regulatory region, one in the negative and two in the positive regulatory regions. Gel retardation assay showed that Sp1 was one of the factors binding to the positive regulatory region. A nuclear factor binding to the negative regulatory region seemed to be missing in brain.

Alzheimer Disease↗
PubMed1992

Nasal mucociliary transport of chronic sinusitis in children.

Nasal mucociliary function is one of the most important and indispensable mechanisms of the respiratory tract, providing protection against the atmospheric environment. We previously found mucociliary dysfunction in the noses of adult patients suffering from chronic sinusitis. In this study, using the saccharin method, we determined nasal mucociliary function in normal children and in children with chronic sinusitis. The mean (+/- SD) value of saccharin transit time in the nose was 28.2 +/- 19.9 minutes in patients with chronic sinusitis, this being significantly slower than that in the control group of children. The incidence of abnormally slow nasal mucociliary transport time (> 30 minutes) in patients was significantly higher than in controls of the same age. Mucociliary dysfunction may initiate a vicious cycle of self-mediated inflammation and may be important in recovery from chronic respiratory inflammation.

Adolescent↗
PubMed1992

Analysis of the T cell receptor (TcR) regions in the NOD, NON and CTS mouse strains define new TcR V alpha haplotypes and new deletions in the TcR V beta region.

We have analyzed the T cell receptor (TcR) V alpha and TcR V beta regions in the spontaneous mouse model for insulin-dependent diabetes mellitus, the NOD mouse, and compared it to the regions in the two sister strains, the NON and CTS strains. Based on restriction fragment length polymorphism analysis the TcR V alpha region in the NOD mouse is essentially identical to that of the SJL/J strain. In contrast both the NON and CTS strains have a unique TcR V alpha haplotype. Whereas the NOD and NON strains apparently contains all the TcR V beta genes, the CTS mouse has three deletions in the V beta region. Our analysis does not give any indications for the diabetic phenotype of the NOD mouse.

Animals↗
PubMed1992

High-sensitive fluorescent DNA sequencing and its application for detection and mass-screening of point mutations.

We describe a rapid and sensitive DNA sequencing method for an automated fluorescent DNA sequencer (AFDS) and its application for detection of point mutations. The method is based on an improved cycle sequencing procedure in which only 10-50 fmol of template DNA is required. Furthermore, it is able to use crude DNA preparation as a template as well as the purified one. Thus, the improved method provided a simplified procedure for sequencing of various types of DNA, including cosmid DNA, in which purification steps were unnecessary. We also developed a novel system for detection of point mutations using AFDS. A set of four lanes is used for the parallel analysis of single-base profiles of four different samples, instead of for the four-base profile of a sample. The AFDS exhibits the base profiles of the samples with four different colors in the analyzed data, which enables us to identify a mutation as an additional peak with a color specific for the lane. The feasibility of our system was tested by analyzing polymerase chain reaction (PCR)-amplified genomic DNAs from four individuals including a carrier of a mutation of C to T. The mutation was clearly identified as an additional "T" peak of a color specific for the carrier. The mutation was also detectable even if 16 individuals including the carrier were simultaneously analyzed on a set of four lanes (four individual samples for each lane). Thus, the novel system is useful for simultaneous detection of mutations in a large number of individual samples.

Automation↗
PubMed1992

Biphasic effects of exogenous ganglioside GM3 on follicle-stimulating hormone-dependent expression of luteinizing hormone receptor in cultured granulosa cells.

The major ganglioside NeuAc alpha 2-->3Gal beta 1-->4Glc beta 1-->1Cer (GM3) present in cultured rat granulosa cells was examined for potential function in the expression of luteinizing hormone (LH) receptor on the cell surface in response to follicle-stimulating hormone (FSH). Synthesis of GM3 was stimulated concentration-dependently by FSH, and the stimulation was enhanced synergistically by insulin, as revealed by metabolic labeling of glycosphingolipids with [3H]galactose. When granulosa cells were cultured in the media containing GM3 (0.2-20 microM), biphasic changes in FSH-dependent expression of LH receptor were observed, as measured by the binding of 125I-deglycosylated human choriogonadotropin to the intact cells. Exogenous GM3 suppressed expression of LH receptor in the cells treated with a low dose of FSH (20 ng/ml), which was characterized by a low GM3 level, to 30% of control at 10 microM, with a half-maximal inhibitory concentration of 8 microM. In contrast, in the cells treated with a high dose of FSH (100 ng/ml) and insulin, which was characterized by a high GM3 level, expression of LH receptor was enhanced by exogenous GM3, to 148% of control at 10 microM, with a half-maximal effective concentration of 2 microM. Exogenous GM3 produced concomitant changes in the levels of extracellular cAMP. These effects of exogenous GM3 were not accompanied by changes in granulosa cell proliferation. Exogenous GM3 also modulated the LH receptor expression by the synergistic action of 12-O-tetradecanoylphorbol 13-acetate with insulin, with no significant changes in cellular DNA contents, suggesting that exogenous GM3 does not modulate directly the action of FSH at its receptor sites.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

Indirect effects of progesterone on the synthesis and secretion of prolactin in mammotroph-enriched cells.

To elucidate the role of steroid hormones in the synthesis and secretion of prolactin (PRL), a mammotroph-enriched cell preparation was made by centrifugal elutriation of trypsin-dispersed anterior pituitary cells from adult male rats. The mammotrophs were enriched by about 2-fold in comparison with those in the initial cell suspension. On the other hand, the ratio of enrichment of gonadotrophs, thyrotrophs and somatotrophs was less than onetenth. The separated mammotrophs were incubated in media containing 17 beta-estradiol and/or progesterone. 17 beta-estradiol increased the levels of PRL in the medium and the cells of 300% and 140%, respectively, and the content of messenger RNA (mRNA) to 193%, whereas progesterone had no such effects. Furthermore, progesterone had no influence on the 17 beta-estradiol-induced increase in the levels of PRL and the contents of PRL mRNA. These results suggest that 17 beta-estradiol regulates PRL synthesis and secretion in mammotrophs, whereas progesterone does not.

Animals↗
PubMed1992

Japanese Type A behavior pattern is associated with "typus melancholicus": a study from the sociocultural viewpoint.

An examination of the relationship between Type A behavior pattern (TABP) and "Typus Melancholicus" (TM) in 212 coronary heart disease (CHD) patients in Japan revealed that: CHD patients with TABP were significantly more likely to have a depression-prone personality, what Tellenbach calls "Typus Melancholicus"; this tendency was observed not only in CHD patients but also among healthy Type A subjects; and TM is positively correlated with Type A. The results of our studies from a comparative sociocultural viewpoint indicate that TM may be involved in Japanese TABP, suggesting the possibility that driving, self-sacrificing and obsessional traits are related to Type A behavior in a variety of different cultural contexts.

Adult↗
PubMed1992

Inhibitory effects of glycyrrhetic acid and its related compounds on 3 alpha-hydroxysteroid dehydrogenase of rat liver cytosol.

Glycyrrhetic acid (GA), aglycone of glycyrrhizin (GL), inhibited potently (I50 = 7 x 10(-6) M) and non-competitively the activity of NAD(P)+-linked 3 alpha-hydroxysteroid dehydrogenase of rat liver cytosol. The inhibition was slightly weaker than that of indomethacin, a potent anti-inflammatory agent, but stronger than that of dexamethasone, another anti-inflammatory agent. GL, GA monoglucuronide, and 3-epi-glycyrrhetic acid also inhibited this enzyme activity, but did so less effectively (I50 = 5-8 x 10(-5) M). Carbenoxolone (GA 3-hemisuccinate) and 3-keto-glycyrrhetic acid showed potent inhibitory effects similar to GA, and 18 alpha-GA showed the most powerful inhibition of the activity.

3-Hydroxysteroid Dehydrogenases↗
PubMed1992

Isolation of novel lignans, heteroclitins F and G, from the stems of Kadsura heteroclita, and anti-lipid peroxidative actions of heteroclitins A-G and related compounds in the in vitro rat liver homogenate system.

From the stems of Kadsura heteroclita, two new lignans named heteroclitins F and G were isolated and their structures were determined by various spectroscopic means including an X-ray diffraction method. Dibenzocyclooctadiene type lignans and related compounds isolated from the stems of K. heteroclita, potently inhibited the lipid peroxidation in the rat liver homogenate stimulated by Fe(2+)-ascorbic acid, CCl4-reduced form of nicotinamide adenine dinucleotide phosphate (NADPH) and adenosine 5'-diphosphate-NADPH.

Animals↗
PubMed1992

Effects of anti-epileptic drugs on the L-tryptophan binding to human serum albumin.

Effects of four anti-epileptic drugs (AED; phenobarbital, phenytoin, carbamazepine and sodium valproate) on the L-tryptophan binding to human serum albumin were studied. Among these drugs examined, only sodium valproate inhibited the binding even within the concentrations of its therapeutic range, and the Klotz plotting analysis revealed that the inhibition was competitive. The results of examinations with sera from epileptic patients medicated with these AED and drug-free normal controls also suggested that the protein binding ratios of L-tryptophan were decreased in the blood plasma of some patients with the high valproate concentrations and the low albumin contents.

Anticonvulsants↗
PubMed1992

Constituents of the roots of Cynanchum bungei Decne. Isolation and structures of four new glucosides, bungeiside-A, -B, -C, and -D.

Four new glucosides, bungeiside-A, -B, -C, and -D, were isolated from the roots of Cynanchum bungei Decne. The structures of the new compounds were determined by chemical and spectroscopic methods, including two-dimensional nuclear magnetic resonance (2D NMR) techniques, especially 1H-detected heteronuclear multiple-bond multiple-quantum coherence.

Acetophenones↗