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H Tsujimoto

Publications and source records attributed to H Tsujimoto.

At least 55 records · Page 3Linked to original sources

QTL analysis of fertility-restoration against cytoplasmic male sterility in wheat.

The cytoplasm of Triticum timopheevi causes cytoplasmic male sterility (CMS) in common wheat (T. aestivum) cv. 'Chinese Spring' (CS), and that of Aegilops kotschyi causes CMS in spelt wheat (T. spelta) var. duhamelianum (Sp). CS has fertility-restoring (Rf) genes against the latter cytoplasm and Sp has the ones against the former. To know the genetic system concerning to CMS, we crossed 66 F8 recombinant inbred lines (RILs) derived from a cross between CS and Sp as males to the alloplasmic lines of CS and Sp having the cytoplasms of T. timopheevi and Ae. kotschyi, respectively. The fertilities of respective F1 plants derived from the crosses were examined for QTL analysis. The major QTLs detected in both systems were located on the short arm of chromosome 1B. One minor QTL on chromosome 2B was also commonly detected in both of the systems, while other minor QTLs against T timopheevi cytoplasm were distributed on the chromosomes 2A, 4B, and 6A.

Animals↗

Molecular cloning of canine thymus and activation-regulated chemokine (TARC) gene and its expression in various tissues.

Thymus and activation-regulated chemokine (TARC) is known as a functional ligand for CC chemokine receptor 4 (CCR4), which is selectively expressed on Th2 lymphocytes and induces selective migration of the cells to allergic lesions. In this study, we cloned canine TARC cDNA from canine thymus by RT-PCR with rapid amplification of cDNA ends (RACE) method. The canine TARC clone contained a full-length open reading frame encoding 99 amino acids and included four cysteine residues characteristic to CC chemokine family. The canine TARC cDNA showed 77.5%, 67.4%, and 68.5% amino acid sequence similarity with human, mouse and rat homologues, respectively. Expression of TARC mRNA was detected not only in thymus but also in spleen, lymph node, lung and heart of the various normal dog tissues examined. TARC cDNA clone obtained in this study will be useful for further investigation on allergic diseases in dogs.

Amino Acid Sequence↗

Increase in plasma lipid peroxide in cats fed a fish diet.

Plasma lipid peroxide levels were examined in cats. Plasma lipid peroxide levels in 3 of 4 clinical cases which had been fed raw fish were higher than those in normal cats. When healthy cats were put on a raw fish diet in controlled conditions, a remarkable increase in plasma lipid peroxide was observed. This increase occurred within 1 to 3 weeks in cats without obvious clinical disorders. We also showed that a continuous raw fish diet is necessary to cause the increase, but the increase was transient and restored in spite of a continuous raw fish diet, indicating the development of an unidentified antioxidant process. Our results clearly indicate that intake of foods high in polyunsaturated fatty acid can induce oxidative stress in cats.

Animal Feed↗

Molecular cloning of feline hepatocyte growth factor (HGF) cDNA.

Hepatocyte growth factor (HGF) is a pleiotropic cytokine responsible for regeneration, development and maintenance of various organs, and growth, invasion and metastasis of tumor cells. A full-length feline HGF cDNA was cloned and sequenced by RT-PCR from cat liver. Feline HGF consists of 728 amino acid and contains alpha- and beta-chains encoded in a single open reading frame. The predicted amino acid sequence of feline HGF showed 93.2, 93.3 and 93.3% homology with those of human, mouse and rat HGF, respectively. The putative proteolytic processing site, all cysteine residues, and four potential glycosylation sites are conserved in all species. Therefore, feline HGF is expected to have a similar three-dimensional structure to human, mouse and rat HGF.

Amino Acid Sequence↗

Pneumocystis carinii pneumonia in a Cavalier King Charles Spaniel.

Pneumocystis carinii pneumonia was diagnosed by postmortem examination of a one-year-old Cavalier King Charles Spaniel with four-week history of dyspnea. Cytologic and histologic examination of lung tissues revealed numerous P. carinii trophozoites and cysts, and P. carinii specific DNA was detected by polymerase chain reaction. The dog showed hypogammagloblinemia and extremely low levels of serum IgG. It was considered that P. carinii pneumonia in this case was associated with an immunodeficient condition which has already been reported in Miniature Dachshunds.

Animals↗

Seasonal rhinitis in a cat sensitized to Japanese cedar (Cryptomeria japonica) pollen.

A cat showing seasonal allergic symptoms of rhinitis was examined for reactivities to Japanese cedar (Cryptomeria japonica, CJ) pollen allergen by intradermal skin test (IDST), Prausnitz-Kustner (P-K) test, and lymphocyte blastogenic response. In IDST for 26 common allergens. the cat showed a positive reaction to CJ pollen allergen. P-K test using CJ pollen allergen also showed a positive reaction, indicating the presence of serum IgE specific to CJ pollen. In the lymphocyte blastogenic response, the stimulation index in the presence of CJ pollen allergen was 2.4. These data suggested that the seasonal rhinitis observed in the cat was caused by the sensitization to CJ pollen allergen.

Animals↗

Results of hyperamplification of centrosomes in naturally developing tumors of dogs.

OBJECTIVE: To evaluate results of centrosome hyperamplification in naturally developing tumors of dogs. SAMPLE POPULATION: Tumor specimens from 9 dogs with tumors (rhabdomyosarcoma, osteosarcoma, chondrosarcoma, myxosarcoma, and mammary gland tumor) and 2 canine osteosarcoma cell lines. PROCEDURE: 3 antibodies for centrosome proteins (ie, anti-gamma-tubulin, anti-BRCA1, and anti-pericentrin) were used for immunohistochemical analysis. Double immunostaining for centrosomes was used to confirm the specificity of these antibodies for centrosomes. Mutational analysis of the canine p53 gene was carried out by polymerase chain reaction-single-strand conformation polymorphism analysis, and expression of canine MDM2 protein was evaluated by use of immunohistochemical analysis, using anti-MDM2 antibody. RESULTS: Immunohistochemical analysis of dog osteosarcoma cell lines with apparent aneuploidy revealed frequent hyperamplification of centrosomes in the osteosarcoma cell lines. Similar hyperamplified centrosomes were detected in the tumor tissues from all of the 9 tumors. The frequency of cells with hyperamplified centrosomes (3 to 20/cell) in each tumor tissue ranged from 9.50 to 48.1%, whereas centrosome hyperamplification was not observed in normal lymph nodes from these dogs. In 8 of the 9 tumors, mutation of p53 gene or overexpression of MDM2, or both, was detected. CONCLUSIONS AND CLINICAL RELEVANCE: Various types of naturally developing tumors in dogs often have hyperamplification of centrosomes associated with chromosome instability. Hyperamplification of centrosomes is a novel tumor marker for use in cytologic and histologic examinations of clinical specimens obtained from dogs.

Animals↗

Telomere length and telomerase activity in canine mammary gland tumors.

OBJECTIVE: To measure telomere length and telomerase activity in naturally occurring canine mammary gland tumors. SAMPLE POPULATION: 27 mammary gland tumor specimens obtained during resection or necropsy and 12 mammary gland tissue specimens obtained from healthy (control) dogs. PROCEDURE: Telomere length in tissue specimens was measured by use of restriction endonuclease digestion and Southern blot analysis. Telomerase activity was measured by use of a telomeric repeat amplification protocol assay. RESULTS: Telomere length in mammary gland tumors ranged from 11.0 to 21.6 kilobase pairs (kbp; mean +/- SEM, 14.5+/-0.5 kbp) but did not differ among tumor types. Telomeres in mammary gland tumors were slightly shorter than in normal tissue specimens, but telomere length could not be directly compared between groups, because mean age of dogs was significantly different between groups. Age was negatively correlated with telomere length in control dogs but was not significantly correlated with length in affected dogs. Telomerase activity was detected in 26 of 27 mammary gland tumors and in 4 of 12 normal tissue specimens. However, telomerase activity and telomere length were not correlated in tumor specimens. CONCLUSIONS AND CLINICAL RELEVANCE: Telomere length is maintained in canine mammary gland tumors regardless of the age of the affected dog. Measurement of telomere length may be a useful tool for monitoring the in vivo effects of telomerase inhibitors in dogs with tumors.

Adenocarcinoma↗

Aberrations of the p53 tumor suppressor gene in various tumors in dogs.

OBJECTIVE: To evaluate aberrations of the p53 tumor suppressor gene in naturally developing tumors in dogs. SAMPLE POPULATION: Tumor specimens from 15 dogs with various tumors, including malignant lymphoma (7 dogs), monocytic leukemia (1), mammary gland adenoma (1), mammary gland benign mixed tumor (1), rhabdomyosarcoma (1), colon cancer (1), and osteosarcoma (3). PROCEDURE: Aberrations of the p53 gene in these tumor tissues were examined by reverse transcriptase-polymerase chain reaction and single-strand conformation polymorphism analysis, using 3 fragments that covered the entire open reading frame of the canine p53 gene, followed by nucleotide sequencing of the abnormal bands. RESULTS: Point mutations, deletions, and insertions resulting in a number of amino acid substitutions of wild-type p53 were detected in 7 of the 15 tumor specimens from dogs with malignant lymphoma, monocytic leukemia, rhabdomyosarcoma, colon cancer, and osteosarcoma. Of these 7 dogs, 2 had aberrations of the p53 gene on both alleles, whereas 5 had aberrations of the p53 gene on 1 allele and concurrently lacked the wild-type p53 transcript. Many of the aberrations of the p53 gene detected in these tumors were located in the transactivation, DNA binding, and oligomerization domains. CONCLUSIONS AND CLINICAL RELEVANCE: Various naturally developing tumors in dogs often have inactivation of the p53 tumor suppressor gene, which may be 1 of the multiple step-wise genetic changes during tumorigenesis. This study indicates that p53 gene can be a target for gene therapy for tumors in dogs.

Animals↗

Examination of the oncogenic potential of H19 gene in HeLa x normal human fibroblast hybrid cells.

Fusion of tumorigenic HeLa cells with human skin fibroblasts results in chromosomally stable non-tumorigenic hybrids. The studies of rare spontaneous tumorigenic segregants from the non-tumorigenic hybrid have implicated the loss of one copy of human fibroblast chromosome 11 with concomitant re-expression of tumorigenicity. In a previous study of differential display screening, we reported the tumorigenic-specific expression of H19 gene as a possible candidate for elicitation of tumorigenic phenotype. In this study, we examined the expression of H19 gene using gamma-ray-induced tumorigenic mutants (GIMs) and non-tumorigenic irradiated control cells (CONs) from the non-tumorigenic hybrids. H19 expression was recognized in all the GIMs with various expression levels, whereas no CONs expressed the H19 gene. To examine the tumorigenic potentials of H19 gene directly, we introduced an H19 gene expression vector into the non-tumorigenic hybrids and assayed the tumorigenicity of the transfectants by s.c. injection into athymic nude mice. However, no transfectants with stable H19 gene expression induced in vivo tumor growth. These results suggest that expression of the H19 gene may be necessary but is not sufficient to confer the tumorigenic phenotype in HeLa x fibroblast hybrids.

Animals↗

Inhibitory effect of serine protease inhibitors on neutrophil-mediated endothelial cell injury.

To investigate the inhibitory effect of serine protease inhibitors (SPI) on neutrophil-mediated endothelial cell (EC) injury, we analyzed the in vitro cytotoxicity of radiolabeled human umbilical vein EC (HUVEC) mediated by neutrophils in the presence of SPI. The EC injury was inhibited dose-dependently by urinary trypsin inhibitor (ulinastatin, UTI) and ONO-5046, which have the ability to inactivate neutrophil elastase, but not by gabexate mesilate, nafamostat mesilate, aprotinin, and argatroban, which have no ability to inactivate neutrophil elastase. In addition, when UTI and ONO-5046 were added to the tumor necrosis factor alpha-primed neutrophils alone, they showed a dose-dependent inhibition of the intracellular elastase activity, but the other SPI did not, for either flow cytometry or confocal microscopy. Therefore, UTI and ONO-5046 may protect EC against the neutrophil-mediated injury not only by inactivating the extracellular elastase secreted by neutrophils, but also by acting directly on neutrophils and suppressing the production and secretion of activated elastase from them.

Cells, Cultured↗

Large-scale selection of lines with deletions in chromosome 1 B in wheat and applications for fine deletion mapping.

Terminal deletions of chromosome 1B in common wheat were selected on a large scale. The gametocidal gene of Aegilops cylindrica was used as the inducer of chromosome breakage. First, genes for endosperm storage proteins located on both arms of chromosome 1B were used as the selection markers. However, it was found that the chromosome breakage occurred during female gametogenesis, causing genotypic inconsistency between the embryo and endosperm. Thus, we isolated plants with terminal deletions in chromosome 1B by C-banding. Of 1327 plants examined, 128 showed aberrations in chromosome 1B: 47 in the short arm, 76 in the long arm, and 5 in both arms. The present deletions tended to have the breakpoint at more proximal regions than those produced previously by T.R. Endo and B.S. Gill. Using 33 deletion lines produced in this study and 34 lines previously produced, we mapped 39 RFLP loci and a nucleolar organizer region (NOR) on a specific region of chromosome 1B. The NOR was found to consist of two subregions with different repetitive units, which were termed NOR-Bld and NOR-Blp. Based on this fine deletion map and genotypic inconsistency between embryo and endosperm, the features of the gametocidal gene are discussed.

Chromosome Aberrations↗

[Analysis of the action of dextran sulfate as a prophylaxis for peritoneal cancer metastasis, and its acting mechanism].

Although peritoneal cancer metastasis has the highest frequency of postoperative recurrence among digestive organ malignant tumors, there is no still decisive treatment. Dextran sulfate (DS) as a prophylaxis for cancer metastasis was examined with respect to its effect on cultured cells. DS was made to act on a strong adhesive neoplasm cell, and the action and acting mechanism were examined with respect to 1. readhesiveness, 2. cell cycle, and 3. gene analysis. The results suggest that: i) Once tumor cells are detached by DS, the free cells do not attach even when DS is removed, and ii) DS causes the cells to stop in the G1/G0 phase.

Animals↗

Identification of Sporothrix schenckii based on sequences of the chitin synthase 1 gene.

Sporothrix schenckii is pathogenic to human and animals. To detect S. schenckii in the tissue, we designed specific oligonucleotide primers based on the chitin synthase gene. Amplification products were selectively obtained from S. schenckii DNA. Polymerase chain reaction analysis with the primer pair S2-R2 was able to detect 10 pg genomic DNA of S. schenckii with ethidium bromide staining. This detection system will be useful as a microbiological tool for the diagnosis of human and animal sporotrichosis.

Base Sequence↗

Detection of circulating lipopolysaccharide-bound monocytes in children with gram-negative sepsis.

The possibility that gram-negative sepsis can be diagnosed by detection of lipopolysaccharide (LPS) bound on the surface of monocytes in the circulation of patients with gram-negative sepsis was investigated. Peripheral monocytes were analyzed by flow cytometer and an anti-LPS monoclonal antibody in 3 groups: children with gram-negative sepsis, children with gram-positive sepsis, and healthy children. LPS-bound monocytes were found in all patients with gram-negative sepsis but not in children with gram-positive sepsis or in healthy children. Therefore, the flow cytometry method developed for this study may be a novel method for diagnosing gram-negative sepsis.

Adult↗

First isolation of Exophiala dermatitidis from a dog: identification by molecular analysis.

The present study deals with the first isolation of Exophiala dermatitidis from a dog. The dog had a history of multicentric lymphoma for 4 months. On physical examination, 10-15 black or purple subcutaneous nodules were detected on the dorsum of the right neck. Microscopic examination of biopsy specimen from the nodules disclosed lymphocytes, neutrophils and moniliform hyphae. The colony of the clinical isolate was flat with black aerial hyphae and a wet margin after 2 weeks incubation on Sabouraud's dextrose agar at 27 degrees C. The microscopic examination of the clinical isolate revealed that hyphae were brown, septate, and smooth, producing branched or unbranched conidiospores laterally or on the apex. The conidia were one celled, subglobose, elliptical to cylindrical, smooth and hyaline. Nucleotide sequence analysis of the chitin synthase 2 (CHS2) gene fragments from the isolate and a reference strain of E. dermatitidis showed more than 99% similarity.

Animals↗