Biomedical subjects

Y Matsuda

Publications and source records attributed to Y Matsuda.

At least 91 records · Page 5Linked to original sources

PubMed2001

Construction of comparative cytogenetic maps of the Chinese hamster to mouse, rat and human.

We constructed comparative cytogenetic maps of the Chinese hamster to mouse, rat and human by fluorescence in-situ hybridization using 36 cDNA clones of mouse, rat, Syrian hamster, Chinese hamster and human functional genes. In this study, 30 out of the 36 genes were newly mapped to Chinese hamster chromosomes. The chromosomal homology of the Chinese hamster was identified and arranged in 19, 19 and 18 segments of conserved synteny in mouse, rat and human, respectively. Additionally, two of the 19 segments homologous to mouse chromosomes were initially identified in this study.

Animals↗

PubMed2001

Conservation of the rat X chromosome gene order in rodent species.

We constructed the comparative cytogenetic maps of X chromosomes in three rodent species, Indian spiny mouse (Mus platythrix), Syrian hamster and Chinese hamster, using 26 mouse cDNA clones. Twenty-six, 22 and 22 out of the 26 genes, which were mapped to human, mouse and rat X chromosomes in our previous study, were newly localized to X chromosomes of Indian spiny mouse, and Syrian and Chinese hamsters, respectively. The order of the genes aligned on the long arm of human X chromosome was highly conserved in rat and the three rodent species except mouse. The present results suggest a possibility that the rat X chromosome retains the ancestral form of the rodent X chromosomes.

Animals↗

PubMed2001

Serum levels of soluble adhesion molecules in stem cell transplantation-related complications.

To assess the involvement of vascular endothelial cell activation and damage in stem cell transplantation (SCT)-related complications, such as acute and chronic GVHD and thrombotic microangiopathy (TMA), we investigated the changes in serum levels of soluble forms of vascular cell adhesion molecule-1 (sVCAM-1) and E-selectin (sE-selectin) in SCT. The soluble form of intercellular adhesion molecule-1 (sICAM-1) was also analyzed. In patients with acute GVHD (grades II-IV), serum levels of sE-selectin and sICAM-1 increased around onset of GVHD (day 30). While the increase of sE-selectin levels was transient, sICAM-1 levels remained high until day 60. In patients with extensive chronic GVHD, sVCAM-1 as well as sE-selectin levels significantly increased. The appearance of clinical symptoms was preceded by elevations of sVCAM-1 and sE-selectin levels on day 60, and sICAM-1 levels on days 30 and 60. For the analysis of TMA, to exclude the influence of GVHD, serum levels were measured in auto-SCT patients. Around the onset of TMA, sVCAM-1 and sE-selectin levels significantly increased in patients with TMA without an increase of sICAM-1 levels. These findings support the notion that activation and injury of endothelium are commonly involved in the pathogenesis of acute and chronic GVHD and TMA.

Adolescent↗

PubMed2001

Inverse relationship between human herpesvirus-6 and -7 detection after allogeneic and autologous stem cell transplantation.

Human herpesvirus-6 (HHV-6) and -7 were analyzed in 25 and 18 patients with allogeneic (allo) and autologous (auto) stem cell transplantation (SCT), respectively, by weekly examination of viral DNA in peripheral mononuclear cells using semiquantitative PCR and serologic tests up to 12 weeks after SCT. HHV-6 DNA was detected in 29.6% and 27.9% of samples after allo- and auto-SCT, respectively. The proportions of HHV-6-DNA-positive samples increased in week 3 and 4 after allo-SCT, and in week 1 to 3 after auto-SCT. The frequency of HHV-7 DNA detection, however, was higher after auto-SCT (24.7%) than allo-SCT (12.8%) (P 10(2) copies of HHV-6 DNA (/10(5) cells) on two consecutive occasions were allo-SCT recipients and three showed clinical episodes. Conversely, three of five patients with continuous reactivation of HHV-7 were auto-SCT recipients. Thus, the frequencies of HHV-6 and -7 DNA detection showed an inverse relationship comparing allo- and auto-SCT, suggesting a different mechanism may regulate HHV-6 and -7 reactivation.

Adolescent↗

PubMed2001

Foscarnet therapy for ganciclovir-resistant cytomegalovirus retinitis after stem cell transplantation: effective monitoring of CMV infection by quantitative analysis of CMV mRNA.

We report three pediatric patients with ganciclovir-resistant cytomegalovirus (CMV) retinitis who were successfully treated with foscarnet. The patients were recipients of hematopoietic stem cell transplantation (SCT) from HLA-mismatched donors. Because these patients had developed or experienced progressive CMV retinitis during ganciclovir therapy, they received foscarnet therapy at 60 mg/kg every 8 h. Their retinitis resolved promptly after initiating foscarnet therapy, suggesting foscarnet's effectiveness in treating ganciclovir-resistant CMV infection. The amount of CMV mRNA was quantitatively measured using an NASBA technique, which amplified the beta2.7 transcripts specific for CMV replication. This technique was useful for monitoring disease activity in a more rapid and sensitive manner than the PCR assay for CMV DNA.

Adolescent↗

PubMed2001

Determination of indomethacin polymorphic contents by chemometric near-infrared spectroscopy and conventional powder X-ray diffractometry.

A chemoinfometric method for the quantitative determination of the crystal content of indomethacin (IMC) polymorphs, based on Fourier-transform near-infrared (FT-NIR) spectroscopy, was established. A direct comparison of the data with those collected using the conventional powder X-ray diffraction method was performed. Pure alpha and gamma forms of IMC were prepared using published methods. Powder X-ray diffraction profiles and NIR spectra were recorded for six kinds of standard material with various contents of the gamma form of IMC. Principal component regression (PCR) analyses were performed on the basis of the normalized NIR spectral sets of standard samples with known contents of the gamma form of IMC. A calibration equation was determined to minimize the root mean square error of the prediction. The predicted gamma form contents were reproducible and had a relatively small standard deviation. The values of the gamma form contents predicted by the two methods were in close agreement. The results indicated that NIR spectroscopy provides an accurate quantitative analysis of crystallinity in polymorphs compared with the results obtained by conventional powder X-ray diffractometry.

Anti-Inflammatory Agents, Non-Steroidal↗

PubMed2001

Chicken microsatellite primers are not efficient markers for Japanese quail.

Domestic fowl or chicken (Gallus gallus) and Japanese quail (Coturnix japonica) belong to the family Phasianidae. The exchange of marker information between chicken and quail is an important step towards the construction of a high-resolution comparative genetic map in Phasianidae, which includes several poultry species of agricultural importance. We tested chicken microsatellite markers to see if they would be suitable as genetic linkage markers in Japanese quail. Twenty-six per cent (31/120) of chicken primers amplified individual loci in Japanese quail and 65% (20/31) of the amplified loci were found to be polymorphic. Eleven of the polymorphic loci were excluded as uninformative because of the lack of amplification in some individuals or high frequency of nonspecific amplification. The sequence information of the remaining nine loci revealed six of them to contain microsatellites that were nearly identical with those of the orthologous regions in chicken. For these six loci, allele frequencies were estimated in 50 unrelated quails. Although the very few chicken markers that do work well in quail could be used as anchor points for a comparative mapping, most chicken markers are not useful for studies in quail. Therefore, more effort should be committed to developing quail-specific markers rather than attempting to adapt chicken markers for work in quail.

Animals↗

PubMed2001

Structure and promoter analysis of the mouse membrane-bound transferrin-like protein (MTf) gene.

Recently, we purified membrane-bound transferrin-like protein (MTf) from the plasma membrane of rabbit chondrocytes and showed that the expression levels of MTf protein and mRNA were much higher in cartilage than in other tissues [Kawamoto T, Pan, H., Yan, W., Ishida, H., Usui, E., Oda, R., Nakamasu, K., Noshiro, M., Kawashima-Ohya, Y., Fujii, M., Shintani, H., Okada, Y. & Kato, Y. (1998) Eur. J. Biochem. 256, 503--509]. In this study, we isolated the MTf gene from a constructed mouse genomic library. The mouse MTf gene was encoded by a single-copy gene spanning approximately 26 kb and consisting of 16 exons. The transcription-initiation site was located 157 bp upstream from the translation-start codon, and a TATA box was not found in the 5' flanking region. The mouse MTf gene was mapped on the B3 band of chromosome 16 by fluorescence in situ hybridization. Using primary chondrocytes, SK-MEL-28 (melanoma cell line), ATDC5 (chondrogenic cell line) and NIH3T3 (fibroblast cell line) cells, we carried out transient expression studies on various lengths of the 5' flanking region of the MTf gene fused to the luciferase reporter gene. Luciferase activity in SK-MEL-28 cells was higher than in primary chondrocytes. Although no luciferase activity was detectable in NIH3T3 cells, it was higher in chondrocytes than in ATDC5 chondrogenic cells. These findings were consistent with the levels of expression of MTf mRNA in these cells cultured under similar conditions. The patterns of increase and decrease in the luciferase activity in chondrocytes transfected with various 5' deleted constructs of the MTf promoter were similar to that in ATDC5 cells, but differed from that in SK-MEL-28 cells. The findings obtained with primary chondrocytes suggest that the regions between -693 and -444 and between -1635 and -1213 contain positive and negative cis-acting elements, respectively. The chondrocyte-specific expression of the MTf gene could be regulated via these regulatory elements in the promoter region.

Amino Acid Sequence↗

PubMed2001

Cloning and characterization of a novel serine/threonine protein kinase gene expressed predominantly in developing brain.

We have isolated a rat gene, sbk, that encodes a novel serine/threonine protein kinase possessing a consensus sequence for an SH3-binding domain from developing rat brain. Rat SBK comprises 417 amino-acid residues consisting of a serine/threonine protein kinase consensus sequence followed by a C-terminal proline-rich region. Sequence comparison with other known kinases revealed that sbk belongs to a novel family of serine/threonine protein kinases structurally related to a Xenopus gastrula-specific protein kinase, Pk9.7. An in vitro kinase assay demonstrated that the SBK protein autophosphorylates at serine/threonine residues. Transcripts of sbk were strongly detected in brain, and the distribution shows an association with neurons but not glial cells. A marked increase in sbk transcripts was observed in developing brain in the late embryonic stage when dramatic neuronal proliferation, migration, and maturation occur. Fluorescence in situ hybridization analysis was used to map sbk to mouse chromosome 7F1-F3 and rat chromosome 1q21. These data suggest a role for SBK in signal-transduction pathways related to the control of brain development.

Amino Acid Sequence↗

PubMed2001

Myb-binding site regulates the expression of glucosamine-6-phosphate isomerase in Dictyostelium discoideum.

A homolog of the glucosamine-6-phosphate isomerase in the cellular slime mold Dictyostelium discoideum has been analyzed. The gene disruption mutant was arrested at the mound stage, demonstrating that the gene is important for development. The gene was expressed in vegetatively growing cells, silenced on starvation and expressed again in prestalk cells during the multicellular stages. The upstream region of the gene (1376 bp relative to ATG) was cloned and sequenced to study the transcription control mechanisms. Analysis of deletion mutants and a site-directed mutant indicated that the Myb-binding sequence (5'-AACTG-3') localized in the upstream region is important for gene expression. The results of gel-shift assays showed the presence of an Myb-related protein binding to the sequence at the growing phase and another protein binding to the sequence at developmental stages.

Aldose-Ketose Isomerases↗

PubMed2001

Familial gastrointestinal stromal tumor with hyperpigmentation: association with a germline mutation of the c-kit gene.

We describe 2 siblings with multiple gastrointestinal stromal tumors (GISTs) and cutaneous hyperpigmentation. Both had a point mutation of the c-kit gene. The patients were sisters who had exhibited cutaneous hyperpigmentation since their late teens, but the diagnosis of multiple gastrointestinal submucosal tumors was not made until they were 41 and 45 years old. Histologic examination showed that these tumors were GISTs expressing CD34 and Kit protein. Both patients died of GISTs. Single-strand conformation polymorphism analysis showed a mutation of c-kit in tumor DNA extracted from paraffin-embedded specimens. Direct sequencing analysis showed that the point mutation occurred at codon 559 of exon 11 (Val-->Ala). The same single-point mutation was detected in DNA extracted from peripheral leukocytes obtained from the younger sister and her 2 children (who had similar general hyperpigmentation) as well as in DNA from a skin biopsy specimen taken from the older sister. The germline mutation at codon 559 of the c-kit gene found in the present familial GISTs differed from that in a previously reported case of familial GISTs. We propose that GISTs caused by a germline mutation of the c-kit gene should be referred to as GIST-cutaneous hyperpigmentation disease.

Adult↗

PubMed2001

Hypercholesterolemia induces leukocyte entrapment in the retinal microcirculation of rats.

PURPOSE: To evaluate leukocyte dynamics in the retinal microcirculation of hypercholesterolemic rats in vivo using acridine orange digital fluorography. METHODS: 18 male pigmented rats were divided into 3 groups according to their diet; (A) control diet (0.1% cholesterol) for 8 weeks, (B) control diet for an initial 4 weeks followed by a high-cholesterol (HC) diet (5% cholesterol) for another 4 weeks and (C) HC diet for 8 weeks. Leukocyte dynamics were observed with acridine orange digital fluorography. The diameter of major retinal vessels and the number of leukocytes trapped in the retina were evaluated quantitatively. RESULTS: Both groups B and C showed approximately 4-fold higher serum cholesterol levels than in group A. The diameters of retinal arteries and veins were not significantly different among the three groups. Also, no rolling leukocytes were observed in any of the groups. In the retinal microcirculation at 30 minutes after acridine orange injection, the density of trapped leukocytes in both groups B and C was significantly greater than in group A (23.19 +/- 2.13, 28.56 +/- 1.96 and 13.67 +/- 1.45 cells/mm(2), respectively, p < 0.01). Furthermore, group C exhibited a significantly greater number of trapped leukocytes than in group B (p < 0.01). CONCLUSION: Enhanced leukocyte entrapment in the retinal microcirculation was induced in the early stage of hypercholesterolemia. Entrapment was increased as the period of hypercholesterolemia was prolonged. Leukocyte accumulation in the retina may be an early vascular dysfunction leading to arteriosclerosis in hypercholesterolemia.

Acridine Orange↗

PubMed2001

Five mouse homologues of the human dendritic cell C-type lectin, DC-SIGN.

DC-SIGN, a human C-type lectin, is expressed on the surface of dendritic cells (DC), while a closely related human gene, DC-SIGNR or L-SIGN, is found on sinusoidal endothelial cells of liver and lymph node. Both DC-SIGN and DC-SIGNR/L-SIGN can bind ICAM-3 and HIV gp120, and transmit HIV to susceptible cells in trans. Here, we report the cloning of five mouse genes homologous to human DC-SIGN and DC-SIGNR/L-SIGN. Only one gene, named mouse DC-SIGN, is highly expressed in DC, and is not found in a panel of mouse macrophage and lymphocyte cell lines. The other four genes, named mouse SIGNR1 (SIGN-Related gene 1), SIGNR2, SIGNR3 and SIGNR4, are expressed at lower levels in various cells according to RT-PCR and Northern blot analyses on RNA. All the genes of mouse DC-SIGN and SIGNRs map to adjacent regions of chromosome 8 A1.2-1.3. However, like human DC-SIGN, only the mouse DC-SIGN gene is closely juxtaposed to the CD23 gene, while the other four SIGNR genes are located close to each other in a neighboring region. mRNAs of mouse DC-SIGN and three SIGNR genes encode type II transmembrane proteins (DC-SIGN, 238 amino acids; SIGNR1, 325 amino acids; SIGNR3, 237 amino acids; SIGNR4, 208 amino acids), but the SIGNR2 gene only encodes a carbohydrate recognition domain (CRD) without a cytosolic domain and a transmembrane domain (SIGNR2, 178 amino acids). Amino acid sequence similarities between the CRD of human DC-SIGN and the mouse homologues are 67% for DC-SIGN, 69% for SIGNR1, 65% for SIGNR2, 68% for SIGNR3 and 70% for SIGNR4 respectively. However, the membrane proximal neck domains in the mouse genes are much shorter than their counterparts in human DC-SIGN and DC-SIGNR/L-SIGN. This family of mouse C-type lectins is therefore complex, but only one of the new genes, DC-SIGN, is juxtaposed to CD23 and is expressed at high levels in DC.

Amino Acid Sequence↗

PubMed2001

Gene structure and chromosomal location of a human bHLH transcriptional factor DEC1 x Stra13 x SHARP-2/BHLHB2.

DEC1/BHLHB2 is a novel cAMP-inducible basic helix-loop-helix (bHLH) transcriptional factor isolated from human chondrocyte cultures by the subtraction method [Shen et al. (1997) Biochem. Biophys. Res. Commun. 236, 294--298]. DEC1 seems to be involved in controlling the proliferation/differentiation of some cell lineages. We determined the structure of the human DEC1 gene and its chromosomal locus. Phylogenetic analysis and comparison of the gene structure showed that the DEC1 protein is a member of a new subgroup of the proline bHLH protein family that diverged earlier than other proline bHLH proteins including HES, hairy and E(spl). The human DEC1 gene spans approximately 5.7 kb and contains 5 exons. The putative promoter region contains multiple GC boxes but no TATA box. A primer extension study showed multiple transcriptional initiation sites. In the 5'-flanking region of the DEC1 gene, several transcriptional factor binding sites, including a cAMP-responsive element (CRE), were found using the transcription factor database. The DEC1 gene locates at Chromosome 3p25.3--26 by the FISH method. This is the first study to determine the genomic structure of the DEC1 gene subgroup.

Amino Acid Sequence↗

PubMed2001

Potato spindle tuber viroid as inducer of RNA silencing in infected tomato.

Potato spindle tuber viroid (PSTVd), an RNA plant pathogen encoding no known proteins, induces systemic symptoms on tomato plants. We report detection of small RNAs of approximately 25 nucleotides with sequence specificity to PSTVd in infected plants: an indication of the presence of RNA silencing. RNA silencing, however, did not appear to be responsible for the differing symptoms induced by a mild and a severe strain of PSTVd. The unique structural and biological features of viroids make them attractive experimental tools to investigate mechanisms of RNA silencing and pathogen counterdefense.

Gene Silencing↗

PubMed2001

Molecular cloning of chicken vasoactive intestinal polypeptide receptor complementary DNA, tissue distribution and chromosomal localization.

Chicken vasoactive intestinal polypeptide receptor (VIPR) cDNA was cloned by the reverse transcription-polymerase chain reaction method using primers designed on the basis of other species of VIPR cDNA. The cDNA obtained was sequenced by the dideoxy-mediated chain-termination method. Of the 2227 nucleotides that were sequenced, 84, 855, and 1338 bases represent the 5'-untranslated region (UTR), the 3'-UTR, and the open reading frame that predicts a peptide of 446 amino acids. The cDNA of the chicken VIPR shows 65% and 60% homologies to human cDNA of VIP1 and VIP2 receptors, respectively. The clone had the expected similarity to highly conserved features of the other G protein-coupled receptors (GPCRs) such as six cysteine residues that are functionally important in the VIPR subfamily. In addition, the seven potential membrane-spanning domains characteristic of the family B group III GPCR superfamily and highly conserved motif within the third cellular loop between transmembrane regions 5 and 6. Northern blot hybridization analysis in this study indicated mRNA expression of VIPRs in the various tissues of the chicken. Strong signal was detected in the brain and anterior pituitary gland. High levels of VIPR mRNA in the brain was consistent with VIP-binding experiments and with the function of VIP in the brain as a neuroendocrine factor or neurotransmitter. Expression of VIPR was detected in the anterior pituitary gland of chick embryos. The expression of VIPR mRNA in the chick anterior pituitary gland may indicate a regulatory function of VIP on prolactin (PRL) production or PRL cell proliferation during embryogenesis. Chicken VIPR shows high homology with mammalian type I VIPR but, in some part, possesses similarity of amino acid sequence. Expression of VIPR in various tissues supports diverse functions for VIP in the chicken.

3' Untranslated Regions↗

PubMed2001

Accuracy of Digora system in detecting artificial peri-implant bone defects.

This study was done to compare the diagnostic accuracy in detecting simulated intrabony defects around fixtures using Digora (DIG; Sordex Orion Corporation, Helsinki, Finland) compared with Ektaspeed Plus film (PLS; Eastman Kodak Co., Rochester, NY). Three titanium implant fixtures were placed in molar areas of three cadavers. Bone defects were created in the interproximal alveolar crest. Exposure time was adjusted to a PLS film and reduced to 1/5 only for DIG (1/5 DIG). The results of four observers were assessed. Sensitivity, specificity, accuracy, and under the receiver operator characteristic curve (ROC) area were evaluated. Statistical analyses were performed by using Friedman test and one-way ANOVA test. Mean sensitivity/specificity were 0.60/0.85 (DIG), 0.54/0.81 (1/5 DIG), and 0.64/0.58 (PLS). There were no statistically significant differences in the diagnostic accuracies. Digora had an equivalent performance to radiographic film in detecting intrabony defects adjacent to the implants, notwithstanding the amount of 1/5 of the exposure time.

Alveolar Bone Loss↗

PubMed2001

Physiological and molecular biological characterization of intracellular carbonic anhydrase from the marine diatom Phaeodactylum tricornutum.

A single intracellular carbonic anhydrase (CA) was detected in air-grown and, at reduced levels, in high CO(2)-grown cells of the marine diatom Phaeodactylum tricornutum (UTEX 642). No external CA activity was detected irrespective of growth CO(2) conditions. Ethoxyzolamide (0.4 mM), a CA-specific inhibitor, severely inhibited high-affinity photosynthesis at low concentrations of dissolved inorganic carbon, whereas 2 mM acetazolamide had little effect on the affinity for dissolved inorganic carbon, suggesting that internal CA is crucial for the operation of a carbon concentrating mechanism in P. tricornutum. Internal CA was purified 36.7-fold of that of cell homogenates by ammonium sulfate precipitation, and two-step column chromatography on diethylaminoethyl-sephacel and p-aminomethylbenzene sulfone amide agarose. The purified CA was shown, by SDS-PAGE, to comprise an electrophoretically single polypeptide of 28 kD under both reduced and nonreduced conditions. The entire sequence of the cDNA of this CA was obtained by the rapid amplification of cDNA ends method and indicated that the cDNA encodes 282 amino acids. Comparison of this putative precursor sequence with the N-terminal amino acid sequence of the purified CA indicated that it included a possible signal sequence of up to 46 amino acids at the N terminus. The mature CA was found to consist of 236 amino acids and the sequence was homologous to beta-type CAs. Even though the zinc-ligand amino acid residues were shown to be completely conserved, the amino acid residues that may constitute a CO(2)-binding site appeared to be unique among the beta-CAs so far reported.

Algal Proteins↗