Biomedical subjects

Y Matsuda

Publications and source records attributed to Y Matsuda.

At least 433 records · Page 24Linked to original sources

PubMed1996

Histological suture changes following retraction of the maxillary anterior bone segment after corticotomy.

By cephalometric and dental cast analyses, the effects of corticotomy in combination with 45-50 days retraction of the maxillary anterior segment were evaluated in five female Japanese monkeys (Macaca fuscata). In addition, microscopic changes of the related sutures were examined. According to the analyses of the dental casts, the retraction of the maxillary anterior segment in the experimental group was increased when compared with that of the control group. There was no change in occlusal molar relationship. The cephalometric analysis revealed that the "Point A" and "Metal Implant" on the mid-sagittal site between the upper central incisors in the experimental group showed more pronounced retraction than that in two untreated control animals. These results were histologically evaluated by changes of the suture structure: irregularity of functional arrangement of component cells and fibers, an increase in number of cells, resorption and formation of bone, and an enlargement of the suture width. Resorption of tooth roots and alveolar bone, and irregularity of the periodontal ligament were observed. In general, these histological changes appeared more extensive in the control specimens compared with the experimental specimens. The osseous histological changes were mainly observed in the compact bone area, while in the spongy bone area of both control and experimental specimens only minimal changes occurred. These results demonstrated the efficacy of combining a corticotomy procedure with retraction of the maxillary anterior bone segment by an orthodontic force.

Animals↗

PubMed1996

Effects of endothelin B antagonist RES-701-1 on endothelin-induced contractile responses in-vivo and in-vitro in guinea-pigs.

The effects of an endothelin (ET)-receptor B-specific antagonist, RES-701-1, on ET-induced contraction of guinea-pig trachea and on ET-induced bronchoconstriction in anaesthetized guinea-pigs were investigated. In the epithelium-removed tracheal preparation, 1 x 10(-5) M RES-701-1 inhibited contractions induced by the ETB-specific agonist sarafotoxin S6c (pKB = 6.10). In the epithelium-intact tracheal preparation, RES-701-1 (1 x 10(-5) M)inhibited the ET-3-induced contraction (pKB = 5.27), but enhanced the ET-1-induced contraction significantly and shifted the concentration-response curve to the left. The maximal responses of ET-1- and ET-3-induced contraction were augmented by epithelium removal by 1.5 and 1.8-fold, respectively. Against ET-3-induced contraction in the tracheal preparation without epithelium, RES-701-1 (0.3-10 x 10(-6)M) antagonized the contraction in a concentration-dependent manner (pA2 = 5.9). On the other hand, RES-701-1 (1 x 10(-5)M) did not affect ET-1-evoked responses in the trachea without epithelium. The intravenous administration of ET-1 (1.5 nmol/kg-1) or ET-3 (1.5 nmol/kg-1) evoked a biphasic, fast and sustained bronchoconstriction in anaesthetized guinea-pigs pretreated with propranolol (1.0 mg/kg-1). when administered intravenously, RES-701-1 (0.3 or 1.0 mg/kg-1) showed significant reduction in both phases of bronchoconstriction induced by ET-3. As in the case of ET-1-induced bronchoconstriction, rES-701-1 augmented the sustained phase although a significant reduction of the fast phase was observed. These results indicate that RES-701-1 can inhibit the ET-3 induced airway responses not only in-vitro but also in-vivo.

Animals↗

PubMed1996

Intermedilysin, a novel cytotoxin specific for human cells secreted by Streptococcus intermedius UNS46 isolated from a human liver abscess.

A novel cytotoxin (intermedilysin) specific for human cells was identified as a cytolytic factor of Streptococcus intermedius UNS46 isolated from a human liver abscess. Intermedilysin caused human cell death with membrane blebs. Intermedilysin was purified from UNS46 culture medium by means of gel filtration and hydrophobic chromatography. The purified toxin was resolved into major and minor bands of 54 and 53 kDa, respectively, by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. These proteins reacted with an antibody against intermedilysin. Five internal peptide fragments of intermedilysin were sequenced and found to have 42 to 71% homology with the thiol-activated cytotoxin pneumolysin. However, the action of intermedilysin differed from that of thiol-activated cytotoxins, especially in terms of a lack of activation by dithiothreitol and resistance to treatments with N-ethylmaleimide and 5,5'-dithio-bis-(2-nitrobenzoic acid), although cholesterol inhibited the toxin activity. Intermedilysin was potently hemolytic on human erythrocytes but was 100-fold less effective on chimpanzee and cynomolgus monkey erythrocytes. Intermedilysin was not hemolytic in nine other animal species tested. Since human erythrocytes treated with trypsin were far less sensitive to intermedilysin than were the intact cells, a cell membrane protein(s) may participate in the intermedilysin action. These data demonstrated that intermedilysin is distinguishable from all known bacterial cytolysins.

Amino Acid Sequence↗

PubMed1996

Two new members of the murine Sim gene family are transcriptional repressors and show different expression patterns during mouse embryogenesis.

From a cDNA library of mouse skeletal muscle, we have isolated mouse Sim1 (mSim1) cDNA encoding a polypeptide of 765 amino acids with striking amino acid identify in basic helix-loop-helix (89% identify) and PAS (89 % identify) domains to previously identified mSim2, although the carboxy-terminal third of the molecule did not show any similarity to mSim2 or Drosophila Sim (dSim). Yeast two-hybrid analysis and coimmunoprecipitation experiments demonstrated that both of the mSim gene products interacted with Arnt even more efficiently than AhR, a natural partner of Arnt, suggesting a functional cooperativity with Arnt. In sharp contrast with dSim having transcriptional-enhancing activity in the carboxy-terminal region, the two mSims possessed a repressive activity toward Arnt in the heterodimer complex. This is the first example of bHLH-PAS proteins with transrepressor activity, although some genetic data suggest that dSim plays a repressive role in gene expression (Z. Chang, D. Price, S. Bockheim, M. J. Boedigheimer, R. Smith, and A. Laughon, Dev. Biol. 160:315-322, 1993; D. M. Mellerick and M. Nirenberg, Dev. Biol. 171:306-316, 1995). Whole-mount in situ hybridization showed restricted and characteristic expression patterns of the two mSim mRNAs in various tissues and organs during embryogenesis, such as those for the somite, the nephrogenic cord, and the mesencephalon (for mSim1) and those for the diencephalon, branchial arches, and limbs (for mSim2). From sequence similarity and chromosomal localization, it is concluded that mSim2 is an ortholog of hSim2, which is proposed to be a candidate gene responsible for Down's syndrome. The sites of mSim2 expression showed an overlap with the affected regions of the syndrome, further strengthening involvement of mSim2 in Down's syndrome.

Amino Acid Sequence↗

PubMed1996

Endogenous atrial natriuretic peptide inhibits endothelin-1 secretion in dogs with severe congestive heart failure.

Atrial natriuretic peptide (ANP) has been shown to counteract the response of endothelin-1 (ET-1), but whether endogenous ANP actually inhibits the systemic release of ET-1 in vivo has not yet been determined. We administered HS-142-1 (HS), a specific antagonist of the guanylate cyclase-coupled ANP receptor, to conscious dogs with severe congestive heart failure (CHF) produced by rapid right ventricular pacing (n = 5, for 22 days) at doses of 0.3, 1.0, and 3.0 mg/kg at 30-minutes intervals. In the present study, plasma ANP and ET-1 levels were significantly elevated in CHF(348 +/-58 and 4.54 +/- 0.60 pg/ml, respectively compared with those in control dogs (65 +/- 4, P < 0.01, 1.30 +/- 0.17 pg/ml, P < 0.001). HS inhibited plasma guanosine 3',5'-cyclic monophosphate (cGMP) levels, a biological market of endogenous ANP activity, in a dose-dependent manner from 21.8 +/- 2.2 to 7.2 +/- 1.4 pmol/ml (P < 0.001), with concomitant significant increases in plasma ET-1 levels from 4.54 +/- 0.60 to 6.60 +/- 0.72 pg/ml (P < 0.05). There was a significant negative correlation between the decrease in plasma cGMP and the increment in plasma ET-1 (r = -0.64, P < 0.01). Despite these responses, mean arterial pressure and pulmonary arterial pressure did not change significantly. Plasma angiotensin II and arginine vasopressin levels, both of which have been reported to stimulate ET-1 secretion in vitro, also showed no significant changes. These results strongly suggest that endogenous ANP directly inhibits endogenous ET-1 secretion through a cGMP-mediated pathway in chronic severe CHF.

Animals↗

PubMed1996

Rat 5S rDNA spacer sequences and chromosomal assignment of the genes to the extreme terminal region of chromosome 19.

Fragments of the spacer region of genes for rat 5S ribosomal RNA (rDNA), which are tandemly repeated, were amplified by PCR with primers specific to the two ends of the coding region for 5S rRNA. Two amplified fragments of approximately 1.6 kb were subcloned and sequenced. The spacer sequences showed a high degree of sequence identity to each other (99.2%) but substantial divergence from those of analogous mouse clones. The homologous regions in the mouse clones were interrupted by the duplication or deletion of small segments of DNA. A 12-mer, 5'-GGCTCTTGGGGC-3', thought to be responsible for efficient transcription, was located from position -33 to position -22 in the rat -5S clones. The genes were mapped by fluorescence in situ hybridization with cloned fragments of rat 5S rDNA as probe. The genes were localized exclusively in a single telomeric region of chromosome 19.

Animals↗

PubMed1996

Genetic mapping of the mouse stromal cell-derived factor gene (Sdf1) to mouse and rat chromosomes.

Stromal cell-derived factor 1 (SDF1) is a new member of the Cys-X-Cys chemokine family. The chromosomal location of Sdf1, the gene coding mouse SDF1, was determined by fluorescence in situ hybridization (FISH) and molecular linkage analysis. The mouse Sdf1 gene was localized to the R-band-positive F1 band of chromosome 6 by direct R-banding FISH. Interspecific backcross analysis identified the mouse Sdf1 gene locus at 0.8 cM terminal to D6Nit55 and 3.0 cM proximal to D6Mit12. With in situ hybridization using a mouse cDNA clone as a probe, the rat Sdf1 gene was localized to the R-band-positive band 4q42.1, where conserved linkage homology to mouse chromosome 6 has been identified. Although other Cys-X-Cys chemokine genes have been mapped on human chromosome 4, the chromosomal segment where the mouse and rat Sdf1 gene reside have no conserved linkage homology to human chromosome 4. This result suggests that SDF1 is a new chemokine class.

Amino Acid Sequence↗

PubMed1996

Chromosomal assignment of the Bcl2-related genes, Bcl2l and Bax, in the mouse and rat.

The Bcl2-related genes, Bax and Bcl2l (formerly called Bclx), are involved in the regulation of apoptotic cell death, and the chromosome location of these two genes was determined in the mouse and rat by fluorescence in situ hybridization. Bcl2l was localized to mouse chromosome 2H1 and rat chromosome 3q41.2, and Bax was localized to mouse chromosome 7B5 and rat chromosome 1q31.2. Both genes mapped in a region of conserved linkage homology between the two the species. Molecular linkage analysis using interspecific backcross mice revealed the murine Bcl2l locus at 0.7 cM terminal to D2Mit22, and the murine Bax locus at 0.8 cM terminal to D7Nds5.

Animals↗

PubMed1996

Identification and chromosome mapping of the mouse homologue of the human gene (DDX6) that encodes a putative RNA helicase of the DEAD box protein family.

The human DDX6 gene (alias RCK) at chromosome 11 band q23 was identified through the study of the breakpoint of t(11;14)(q23;q32) translocation in a B-cell lymphoma cell line, RC-K8. DDX6 encodes a DEAD box protein/RNA helicase. Positive mouse genomic and cDNA recombinant clones were obtained by screening mouse B-cell genomic and cDNA libraries with a human DDX6 cDNA probe. The deduced amino acid sequence of an open reading frame from a cDNA clone revealed a protein with 92.5% identity to human ddx6/p54. All positive mouse genomic recombinant clones, and cDNA clones containing mouse Ddx6 (previous gene symbol: Rck), were localized by fluorescent in situ hybridization to band B of mouse Chromosome 9, a region showing conserved linkage homology to human chromosome 11 band q23. Mouse Ddx6 was localized to the region between Ncam and D9Mit45 by molecular linkage analysis. A 7.5-kb mRNA and a 54-kDa protein were identified as mouse Ddx6 gene products which are similar in size to products of the human DDX6 gene, as shown by Northern and Western blot analyses.

Amino Acid Sequence↗

PubMed1996

C-type natriuretic peptide as a possible local modulator of aldosterone secretion in bovine adrenal zona glomerulosa.

Although atrial and brain natriuretic peptides are well known to be involved in the regulation of cardiovascular and endocrine functions as circulating hormones, the roles of the C-type natriuretic peptide (CNP) remain unknown. We examined the effects of CNP on the secretion of aldosterone and cyclic nucleotides from bovine adrenal zona glomerulosa cells in culture. CNP produced a dose-dependent increase in the basal secretion of cGMP, with an EC50 of 3.8 x 10(-10)M. CNP significantly inhibited the ACTH-induced increase in aldosterone and cAMP in a dose-related manner, with an IC50 of 3.6 x 10(-10)M. Although ACTH itself did not increase cGMP secretion, the addition of CNP elicited a significant increase in cGMP secretion. The effects of CNP on the basal secretion of cGMP and the ACTH-induced secretion of aldosterone were significantly reversed by a nonpeptide natriuretic peptide receptor antagonist, HS-142-1. CNP immunoreactivity was localized in the zona glomerulosa by immunohistochemical staining. In addition, expression of CNP messenger RNA and natriuretic peptide B receptor messenger RNA was demonstrated by RT-PCR in the zona glomerulosa tissue and cells in culture. These findings suggest that CNP is a local factor regulating ACTH-induced aldosterone secretion through a guanylyl cyclase-cGMP pathway.

Adrenal Glands↗

PubMed1996

Clinical application of basic arginine amidase in human male urine.

Basic human urinary arginine amidase (or esterase, called BHUAE) which is only found in male urine, was measured from normal volunteers between the age of 4 and 70 years using D-valyl-L-leucyl-L-arginine-p-nitroanilide as a substrate. BHUAE increases during early adolescence, between 8 to 17 years of age. Then, BHUAE decreases in the twenties and takes a certain range of value in the mature age group, between the late thirties and fifties. In patients with prostate cancer, a significant increase in BHUAE was demonstrated in comparison with the healthy male group (control) over 55 years old. On the other hand, patients with benign prostatic hypertrophy showed no significant elevation of this enzyme activity. It would appear that the measurement of BHUAE in urine can be used as a marker of prostate cancer in an advanced age group.

Adolescent↗

PubMed1996

Effects of antihypertensive drugs on maternal and fetal hemodynamics and uterine blood flow in pregnant goats--comparison of nicardipine and labetalol.

This study was designed to compare the effects of nicardipine (0.02 mg/kg) and labetalol (0.5 mg/kg) on the uterine blood flow and fetal circulation after intravenous administration in unanesthetized, chronically instrumented pregnant goats. Significant decreases in maternal blood pressure and uterine blood flow were observed in both groups. The maternal heart rate increased significantly after the injection of nicardipine, whereas this change was not observed after the labetalol injection. The fetal heart rate, blood pressure and acid-base status did not change after the injection of either nicardipine or labetalol. These observations in pregnant goats suggest that both nicardipine and labetalol might be useful drugs for the treatment of acutely hypertensive crises in pregnant patients.

Animals↗

PubMed1996

A quantity of stereotyped behavior of ddY mice induced by low-dose methamphetamine.

It is reported that high-dose methamphetamine (8 mg/kg) induces stereotyped behavior in ddY mice in an open field, but it is still not certain that low-dose methamphetamine (less than 2 mg/kg) can induce the stereotyped behavior in ddY mice in a narrow space. In order to investigate the problem, we evaluated the quantity of stereotyped behavior of ddY mice by using a mouse wheel-running apparatus. In this method, we have come to recognize an increase in the stereotyped behavior depending on the dose of methamphetamine and the reverse-tolerance phenomenon as a decrease in the wheel-revolution counts. The present findings indicate that low-dose methamphetamine can promote stereotyped behavior in ddY mice under conditions in which the ambulation is restricted to a narrow wheel space.

Animals↗

PubMed1996

[Changes in intestinal motility after massive small bowel resection with a reversed jejunal segment].

To evaluate the functioning and effectiveness of a 20-cm reversed jejunal segment after 75-80% massive small bowel resection (MSBR), and whether migrating polarity changes or not, we continuously measured the postoperative bowel motility (using bipolar electrodes and/or contractile strain gage force transducers) in interdigestive and postprandial conscious dogs in short- (2-5 weeks) and long-term (6-10 months) after surgery. The fasting migrating myoelectric (or motor) complex (MMC) arising from the duodenum was often interrupted at the jejunum above the proximal anastomosis and did not migrate smoothly to the reversed segment or terminal ileum. In addition, brief small discordant contractions were frequent in the jejunum above the proximal anastomosis and the proximal part of the reversed segment. The duodenal MMCs predominantly propagated to the ileum through the inherent anatomic continuity of the bowel. These findings of the MMC propagation pattern are very similar in short- and in long-term after surgery. The duration of the postprandial period without duodenal MMC activity was markedly longer in short-term, but shorter in long-term (both were significantly longer than in controls). Marked dilatation of the jejunum and reversed jejunal segment was noted across the proximal anastomosis. These results suggest that the transit time and passage of intestinal contents can be delayed and stagnated for at least 10 months after MSBR with a 20-cm reversed jejunal segment. Although, reports on the polarity of peristalsis in the reversed segment in long-term followup have been contradictory in both experimental and clinical studies, this results support the conclusion that the reversed jejunal segment maintains its inherent propagative polarity and pattern over a long postoperative period.

Anastomosis, Surgical↗

PubMed1996

RES-1149-1 and -2, novel non-peptidic endothelin type B receptor antagonists produced by Aspergillus sp. I. Taxonomy of producing strain, fermentation, isolation, and physico-chemical and biological properties.

RES-1149-1 and -2, novel and non-peptidic endothelin antagonists, were isolated from the cultured broth of a fungus, Aspergillus sp. RE-1149. RES-1149-1 and -2 selectively inhibited the ET-1 binding to endothelin type B receptor (ETB receptor) with IC50 values of 1.5 microM and 20 microM, respectively. Taxonomy of producing strains, fermentation, isolation, and physico-chemical properties of RES-1149-1 and -2 are described.

Animals↗

PubMed1996

EI-1511-3, -5 and EI-1625-2, novel interleukin-1 beta converting enzyme inhibitors produced by Streptomyces sp. E-1511 and E-1625. I. Taxonomy of producing strain, fermentation and isolation.

EI-1511-3, -5 and EI-1625-2, novel interleukin-1 beta converting enzyme (ICE) inhibitors, were isolated from the culture broths of Streptomyces sp. E-1511 and E-1625. EI-1511-3, -5 and EI-1625-2 selectively inhibited the recombinant human ICE activity with IC50 values of 0.09, 0.38 and 0.2 microM, respectively. Taxonomy, fermentation of the producing strain and isolation of EI-1511-3, -5 and EI-1625-2 are described.

Amides↗

PubMed1996

EI-1511-3, -5 and EI-1625-2, novel interleukin-1 beta converting enzyme inhibitors produced by Streptomyces sp. E-1511 and E-1625. III. Biochemical properties of EI-1511-3, -5 and EI-1625-2.

EI-1511-3, -5 and EI-1625-2, novel interleukin-1 beta converting enzyme (ICE) inhibitors from the culture broths of Streptomyces sp. selectively inhibited the recombinant human ICE activity with IC50 values of 0.09, 0.38 and 0.2 microM, respectively, without inhibiting elastase and cathepsin B. Manumycin G, ent-alisamycin, U-56,407, and manumycin A and B isolated simultaneously from the same strains also inhibited ICE. EI-1511-3, -5 and EI-1625-2 also inhibited mature interleukin-1 beta secretion from THP-1 cells with IC50 values of 5.4, 3.6 and 2.2 microM, respectively. In this article, biological properties of EI-1511-3, -5 and EI-1625-2 and, in addition, properties of manumycin-related compound are described.

Amides↗

PubMed1996

RES-1149-1 and -2, novel non-peptidic endothelin type B receptor antagonists produced by Aspergillus sp. III. Biochemical properties of RES-1149-1, -2 and structure-activity relationships.

RES-1149-1 and -2, produced by Aspergillus sp. RE-1149, were found to be non-peptidic antagonists for endothelin type B receptor (ET(B) receptor). RES-1149-1 and -2 selectively inhibited the endothelin-1 (ET-1) binding to ET(B) receptor in a competitive manner with IC50 values of 1.5 microM and 20 microM, respectively. RES-1149-1 inhibited the increase in intracellular Ca2+ concentration elicited by 1 nM ET-1 in COS-7 cells expressing human ET(B) receptor, but not in the case of cells expressing ET(A) receptor. In addition, some structure-activity relationships are described.

Animals↗