Biomedical subjects

H Tsujimoto

Publications and source records attributed to H Tsujimoto.

At least 127 records · Page 7Linked to original sources

PubMed1998

Effect of thromboxane synthetase inhibitor on feline infectious peritonitis in cats.

Two cats with abdominal effusion and anorexia were diagnosed as feline infectious peritonitis (FIP). We tried to evaluate the effect of thromboxane (Tx) synthetase inhibitor, ozagrel hydrochloride, on the progression of symptoms and clinicopathologic data characteristic to FIP. After administration of Tx synthetase inhibitor, improvement of appetite and activity, decreases of peritoneal effusion, reduction of leukocyte number to normal level, and improvement of hyper gamma-globulinemia were found in 2 cats with FIP. These findings suggest that the vasculitis in FIP can be successfully treated with Tx synthetase inhibitor which inhibits platelet aggregation.

Animals↗

PubMed1997

Establishment and characterization of a canine T-lymphoblastoid cell line derived from malignant lymphoma.

A canine lymphoma cell line (CL-1) was established in culture from tumor cells found in the pleural fluid of a 7-year old female Japanese terrier with thymic form lymphoma. The CL-1 cells were positive for CD45 and MHC class II and negative for CD4, CD5, CD8, Thy-1 and B-cell specific antigen and surface immunoglobulin. The CL-1 cells had a rearranged T-cell receptor beta-chain gene and a germ-line form immunoglobulin gene, indicating that the CL-1 cells represented a monoclonally expanded population of canine alpha beta T-cell lineage.

Animals↗

PubMed1997

Cloning and chromosome mapping of the feline genes p21WAF1 and p27Kip1.

For investigation of the relation of cell cycle regulation with tumorigenesis in cats, we carried out molecular cloning of feline p21WAF1 and p27Kip1 cDNAs and chromosomal mapping of these genes on the cat genome. The feline p21WAF1 cDNA clone obtained in this study encoded 164 amino acids (aa) showing 83.5% and 76.8% sequence similarity with those of the human and mouse counterparts, respectively. The cat p27Kip1 cDNA clone isolated here encoded 198 aa, showing sequence similarities of 93.4% and 90.4% with its human and mouse counterparts, respectively. Using a panel of feline x rodent somatic cell hybrids, the feline CDKN1A (p21WAF1) and CDKN1B (p27Kip1) loci were assigned to feline chromosomes B2 and B4, respectively. Southern-blot analyses of 17 feline spontaneous leukemia and lymphoma cases using these cDNAs as probes did not reveal any rearrangements in either the p21WAF1 or the p27Kip1 gene. RT-PCR/SSCP (single strand conformation polymorphism) analysis of p27Kip1 cDNA did not uncover any amino acid substitutions in the 10 feline leukemia and lymphoma cases that were examined.

Amino Acid Sequence↗

PubMed1997

Molecular structure of a wheat chromosome end healed after gametocidal gene-induced breakage.

In the progeny of the monosomic addition line of common wheat, Triticum aestivum, carrying the gametocidal chromosome of Aegilops cylindrica, deletion chromosomes carrying the break point within the nucleolar organizing region of chromosome 1B appeared. Attempts were made to amplify the break points by PCR using primers of telomere and rDNA (rRNA gene). In one deletion line, specific amplification of DNA fragments including the 18S rRNA gene, telomere repeats, and their junction occurred. At the junction of telomere and rRNA gene there was a 31-bp inverted duplication of the rRNA gene. Telomere sequences were initiated from the sequence TAG in the duplication. Between the duplications a small sequence was also inserted. This novel DNA sequence at the break point indicates that the breakage-fusion-bridge cycle(s) took place after the first chromatin breakage by the gametocidal gene.

Base Sequence↗

PubMed1997

Cloning and expression of the major porin protein gene opcP of Burkholderia (formerly Pseudomonas) cepacia in Escherichia coli.

The outer membrane protein OpcP1 of Burkholderia (formerly Pseudomonas) cepacia is one of the subunits forming the porin oligomer OpcPO by non-covalent association. OpcP1 was cleaved with lysyl endopeptidase and the N-terminal amino acid (aa) sequences of the polypeptide fragments were determined. Based on the sequence information, we cloned the opcP gene on a 10-kb EcoRI DNA fragment of the B. cepacia ATCC25416 chromosome. Nucleotide (nt) sequencing revealed a 1086-bp open reading frame (ORF), encoding a 361-aa polypeptide with a signal sequence of 20 residues. The predicted opcP gene encoded a mature protein of Mr 35,696, which agrees well with the value observed previously on SDS-PAGE. The opcP was sub-cloned into pTrc99A and introduced into Escherichia coli. Immunoblot analysis using murine antiserum specific to OpcP1 visualized the protein expressed in the E. coli cells after induction by isopropyl beta-D-thiogalactopyranoside (IPTG).

Amino Acid Sequence↗

PubMed1997

Overexpression of bax enhances the radiation sensitivity in human breast cancer cells.

Bax-alpha, a splice variant of bax which promotes apoptosis, is expressed in many kinds of untransformed cell lines and breast tissue, whereas only weak or no expression could be detected in breast cancer cell lines and malignant breast tissue. Human breast cancer MCF-7 cells, which have a weak bax gene expression, were stably transfected with pCX2neo bax, encoding human bax and neomycin-resistant genes, and two unique clones (MCF-7/bax-1 and MCF-7/bax-2) were thus generated which expressed different levels of bax-alpha. Sensitivity to ionizing radiation (IR) was examined and each was more sensitive to IR than the parental MCF-7 cells. The degree of enhancement in radiosensitivity was dependent on the expression level of bax, and IR was found to induce intranucleosomal DNA fragmentation in stable transfectant but not in parent cells, thus suggesting that this sensitization is due to apoptosis. We suggest that exogenous bax-alpha expression might therefore be one of the factors determining cellular radiosensitivity in MCF-7 breast cancer cells and may potentially have a therapeutic application by enhancing radiation sensitivity in breast cancer cells.

Apoptosis↗

PubMed1997

Overexpression of bax sensitizes breast cancer MCF-7 cells to cisplatin and etoposide.

Bax, one of the bcl-2 family genes, is expressed in a number of untransformed cell lines and various breast tissues, whereas only weak or no expression has been detected in breast cancer cell lines and malignant breast tissue. Human breast cancer MCF-7 cells, which have a weak bax gene expression, were stably transfected with pCX2neo bax, encoding human bax; and two unique clones, MCF-7/bax-1 and MCF-7/ bax-2, that expressed different levels of bax were generated. Sensitivity to cisplatin (CDDP) and etoposide (VP-16) was examined and each stable transfectant was more sensitive to these agents than the parental MCF-7 cells. The degree of enhancement in sensitivity to these anticancer agents was dependent on the expression level of bax. The enzyme-linked immunosorbent assay (ELISA), which quantifies DNA damage, demonstrated that this sensitization was due to apoptosis. Thus, we suggest that exogenous bax-alpha overexpression may be one of the factors determining cellular chemosensitivity in MCF-7 breast cancer cells and that it could be applied therapeutically to enhance chemosensitivity in breast cancer cells.

Antineoplastic Agents↗

PubMed1997

Amplification of growth factor receptor genes and DNA ploidy pattern in the progression of gastric cancer.

To study the background of oncogene amplification in gastric cancers, we examined the correlation between occurrence of oncogene amplification and DNA ploidy pattern. In 57 primary gastric cancers, amplifications of c-erbB, c-erbB-2, c-met and K-sam genes were investigated by Southern blot analysis, and the DNA ploidy pattern was determined by static cytofluorometry and by flow cytometry. Oncogene amplification was detected in 11 cancers, 10 of which were advanced gastric cancers and 1 was an early differentiated type. The amplification of c-erbB-2 and K-sam genes was found exclusively in differentiated- and undifferentiated-type cancers, respectively. Of the 11 cancers, 5 were DNA-diploid and 6 were DNA-aneuploid. All the 11 tumours with oncogene amplification contained polyploid cell populations (polyploidy), whereas none of the tumours without polyploidy showed oncogene amplification. In differentiated-type cancers the incidence of polyploidy was high in both early and advanced stages, while in undifferentiated-type cancers it was low in early stages but significantly higher in advanced stages. It was shown that amplification of growth factor receptor genes is closely related to the presence of polyploidy, irrespective of any different stemline DNA-ploidy mode. The time-course of oncogene amplification and kinds of genes amplified may differ between differentiated- and undifferentiated-type gastric cancers.

Adenocarcinoma↗

PubMed1997

Genomic structure of the bovine mb-1 gene encoding the Ig-alpha subunit of the B cell antigen receptor complex.

The B cell antigen receptor, (BCR) comprises surface immunoglobulin and disulfide-bonded heterodimer of Ig-alpha and Ig-beta chains, which are the products of the mb-1 and B29 genes, respectively. In this study, we describe the isolation and analysis of a 6.2-kb genomic DNA clone containing bovine mb-1 gene encoding Ig-alpha. Sequence data revealed that the bovine mb-1 gene is composed of five exons and four introns, and that its overall structure is very similar to those of murine and human genes. The 5' upstream region of the bovine mb-1 gene contained potential protein binding motifs of transcription factors including EBF, Sp1, NF-kappa B, MUF/Ets-1 and AP 2. As with the murine and human mb-1 genes, the 5' region of the bovine mb-1 gene lacked a TATA box. The present study will be useful for understanding the regulated expression of the bovine mb-1 gene at different stages of development and activation as well as in bovine leukemia virus infection.

Amino Acid Sequence↗

PubMed1997

Molecular cloning and functional expression of equine interleukin-1 receptor antagonist.

Equine interleukin-1 receptor antagonist (IL-1ra) was molecularly cloned to establish a basis for cytokine therapy of acute and chronic inflammatory diseases in the horse. cDNA clones encoding the whole coding sequence of equine IL-1ra were isolated from equine peripheral blood mononuclear cells (PBMC) that had been stimulated with lipopolysaccharide (LPS). The equine IL-1ra cDNA obtained in this study contained an open reading frame encoding 177 amino acid residues. The predicted amino acid sequence of equine IL-1ra shared 75.7, 75.3 and 76.3% similarity with sequences of human, murine and rabbit IL-1ras, respectively. An N-glycosylation site and five cysteine residues conserved in human, murine and rabbit IL-1ras were also found at the corresponding positions in equine IL-1ra. Recombinant glutathione S-transferase (GST)-equine IL-1ra fusion protein produced by Escherichia coli was purified. This protein was shown to inhibit the cytostatic or cytotoxic activity of IL-1 on A375S2 cells, indicating that the equine IL-1ra cDNA obtained in this study encodes biologically active equine IL-1ra.

Amino Acid Sequence↗

PubMed1997

Molecular characteristics of malignant lymphomas in cats naturally infected with feline immunodeficiency virus.

Neoplastic disease, especially malignant lymphomas, are often observed in cats infected with feline immunodeficiency virus (FIV). In order to clarify the characteristics of lymphoma cells and to investigate the pathogenesis in FIV-infected cats, we examined the lymphoma tissues developed in five cats naturally infected with FIV by Southern blot analyses using feline immunoglobulin (Ig), T-cell receptors (TCR) and FIV probes. All of the five cases were serologically positive for anti-FIV antibody and negative for feline leukemia virus antigen. Of these five lymphoma samples, two displayed rearrangement of the Ig heavy chain gene and deletion of the Ig light (kappa) chain gene, indicating that the tumor cells were committed to B-cell development. One tumor sample was identified as a T-cell lymphoma because of the presence of a rearranged TCR beta-chain gene. The other two cases were considered to be non-T non-B cell lymphoma because they did not show any rearrangement of the Ig and TCR genes. Therefore, no consistent tumor type was found in lymphoma cases infected with FIV. Clonal integration of FIV provirus was not detected in any of the five lymphoma samples obtained from FIV-infected cats using Southern blot analysis, although FIV proviral genome was detected in the genomic DNA of all the lymphoma samples by using a polymerase chain reaction (PCR). These results indicated that FIV might not play a direct role in tumorigenesis of lymphoma in cats.

Animals↗

PubMed1997

The treatment with differentiation- and apoptosis-inducing agent, vesnarinone, of a patient with oral squamous cell carcinoma.

A patient with histopathological recurrent oral cancer with well-differentiated squamous cell carcinoma, was treated with differentiation- and apoptosis-inducing agent, vesnarinone, per os at a dose of 180 mg/day for 56 days and then at a dose of 60 mg/day for 93 days. The vesnarinone administration caused complete remission of the tumour. It has been found by immunohistochemical staining and PCR-SSCP analysis that the recurrent tumour has wild type p53 gene and relative high level of LeY expression as well as DNA fragmentation in the cancer cells, as assessed by nick-end labelling. These findings suggest that the cure of oral squamous cell carcinoma observed in this case might be associated with induction of differentiation and apoptosis of cancer cells by vesnarinone.

Journal Article↗

PubMed1997

Circulating soluble selectins in Kawasaki disease.

To investigate the significance of circulating adhesion molecules associated with leucocyte-endothelial cell interaction in Kawasaki disease (KD), serum levels of soluble E-, P-, L-selectin (sE-, sP-, sL-selectin), and vascular cell adhesion molecule-1 (VCAM-1) were measured in 16 patients with KD, eight with other febrile diseases, six with Henoch-Schonlein purpura (HSP), and 10 healthy children using an ELISA. Serum sE-selectin levels from patients in the acute phase of KD were significantly higher than from those in other groups (P < 0.01). The levels of sP-selectin in the subacute phase of KD were significantly higher than in other groups (P < 0.01). Serum sL-selectin levels tended to rise in the convalescent phase of KD. There were also significant correlations between sE-selectin levels and C-reactive protein (r = 0.80, P < 0.0001), and between sP-selectin levels and platelet counts (r = 0.57, P < 0.0001) in KD patients. These data indicate that circulating soluble forms of three selectins may have different kinetics during the clinical course of KD, suggesting that they may reflect its inflammatory process.

Child↗

PubMed1997

Selective delivery of 5-fluorouracil (5-FU) to i.p. tissues using 5-FU microspheres in rats.

A new formulation has been developed for the delivery of 5-fluorouracil (5-FU) in treating peritoneal carcinomatosis. The new formulation (5-FU-MS) involves the incorporation of 5-FU into microspheres composed of a poly(glycolide-co-lactide) matrix. The incorporated 5-FU is released slowly over a 3 week period. We investigated the drug distribution and pharmacokinetics of 5-FU in rats receiving an i.p. injection of 5-FU-MS or aqueous 5-FU solution. The concentration of 5-FU was higher in the i.p. tissues (omentum and mesentery) and lower in the extraperitoneal tissues (blood plasma, lung and heart) in rats given 5-FU-MS than in rats given the aqueous 5-FU solution. Pharmacokinetic analysis showed that the area under the curve (AUC) was significantly greater in the omentum and the mesentery than in other tissues of rats given 5-FU-MS. There was no significant difference in the AUC in the tissues of rats given the aqueous 5-FU solution.

Animals↗

PubMed1997

Phylogenetic analysis of 8 dermatophyte species using chitin synthase 1 gene sequences.

Nucleotide sequences of chitin synthase 1 (CHS1) gene of eight species of dermatophytes, Arthroderma benhamiae, A. fulvum, A. grubyi, A. gypseum, A. incurvatum, A. otae, A. simii and A. vanbreuseghemii were obtained and analysed for their phylogenetic relationship. A 600-bp genomic DNA fragment of the CHS1 gene was amplified from these dermatophytes by polymerase chain reaction (PCR) and sequenced. The CHS1 nucleotide sequences of these eight dermatophyte species showed more than 85% similarity between the species. The phylogenetic analysis of their sequences revealed three clusters, the first cluster consisting of A. benhamiae, A. simii and A. vanbreuseghemii, the second cluster consisting of A. fulvum, A. gypseum and A. incurvatum, and the third cluster consisting of A. grubyi and A. otae. The phylogenetic analysis of CHS1 gene in this study will provide useful information for classification and understanding the evolution of these dermatophyte species.

Arthrodermataceae↗

PubMed1997

Differentiation of Arthroderma spp. by random amplification of polymorphic DNA (RAPD) and Southern hybridization.

To develop the molecular differentiation analysis of dermatophytes, we carried out RAPD and Southern hybridization analyses using genomic DNAs of six Arthroderma species, including A. fulvum, A. grubyi, A. gypseum, A. incurvatum, A. otae and A. racemosum. The RAPD analysis gave different band patterns specific to each of the six Arthroderma fungi. However, minor differences in the banding patterns were observed between the strains of plus (+) and minus (-) mating types of A. gypseum, A. fulvum and A. incurvatum. Southern blot analysis using a probe (1S) obtained from A. grubyi DNA gave specific bands only in the DNA samples of A. grubyi and A. incurvatum. On the other hand, Southern blot analysis using a probe (C3) obtained from A. otae DNA gave specific bands in all six Arthroderma species examined, and the size of the bands were specific to each species. These findings indicate that RAPD and Southern hybridization analyses are useful in the differentiation of these Arthroderma species.

Amino Acid Sequence↗

PubMed1997

A case of feline cryptococcosis treated with itraconazole.

We successfully treated a feline case of cryptococcosis with itraconazole (ITZ) at a lower dosage. The patient was a 2-year-old castrated male Abyssinian cat weighing 4.1 kg and with two masses on the head. Clinical signs were sneezing and nasal discharge. The plasma cryptococcal antigen titer measured by the latex agglutination test was proved to be high (512). The biopsy specimen from the masses disclosed yeast cells which were cultured and identified to be Cryptococcus neoformans. The cat was treated with ITZ 5 mg kg-1 given orally once a day with food. After 4 weeks, treatment of ITZ discontinued, because the cat was clinically normal and the antigen titer was low (128). However, about 7 months later, a subcutaneous nodule was detected on the same area. The nasal discharge appeared again, and the cryptococcal antigen titer was 256. ITZ treatment was continued again at the same dosage for 3 months until the antigen titer was negative (< 8). Four months after discontinuation of ITZ, the cat did not relapse and the antigen titer was in the negative range. No side-effects of ITZ were detected by physical and laboratory examination.

Animals↗

PubMed1997

A study of cognitive development and behavior problems in mentally retarded children.

Cognitive development in seventy-one mentally retarded children (19 autistic, 52 non-autistic; aged 7-19 years) from a school for handicapped children was studied, using Ohta's scale for evaluating cognitive development level based on language comprehension (Ohta's stage), and other developmental scales. Behavior problems were also examined. The present study reports on the utility of Ohta's stage in non-autistic children, and the relationship between cognitive development level and behavior problems in mentally retarded children. In non-autistic children, there were temporal correlations between Ohta's stage and other development scales (a standard developmental test, speech development, symbolic play development, imitation development), suggesting that in non-autistic children as well, Ohta's stage may serve well as a scale for cognitive development, and reflect symbolic representational functioning. In non-autistic children, most behavior problems in feeding, elimination and sleeping, hyperkinesis, hypokinesis, stereotyped behaviors, self-injurious behavior and licking were closely associated with cognitive development level, and were more often noted in children of lower cognitive development level rather than only in the severely mentally retarded children. Some behavior problems may often occur in the sensorimotor period and hardly occur in the symbolic representational period.

Adolescent↗