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T Kuramoto

Publications and source records attributed to T Kuramoto.

At least 37 records · Page 2Linked to original sources
PubMed1999

Expression of the tumor-rejection antigen SART1 in brain tumors.

We have reported a tumor-rejection antigen, SART1(259), possessing tumor epitopes capable of inducing cytotoxic T lymphocytes (CTLs) in epithelial-cancer patients. This study investigated the expression of SART1(259) antigen in brain tumors, to explore for a potential molecule for use in specific immunotherapy of patients with brain tumors. The SART1(259) antigen was detected in the cytosol fraction of 13 of 18 (72%) glioma cell lines and in 12 of 34 (35%) brain-tumor tissues, with a higher rate of expression among malignant gliomas (5/10, 50%) and schwannomas (3/4). HLA-A24-restricted and SART1-specific CTLs recognized the HLA-A24+ and SART1(259)+ glioma cells, and the levels of recognition correlated both with HLA-A24-antigen expression level and with the concentration of the SART1 peptide antigen. Therefore, the SART1(259) antigen could be a target molecule for specific immunotherapy of patients with brain tumors expressing HLA-class-1 antigens.

Antigens, Neoplasm↗
PubMed1999

Determining the appropriate stimulus intensity for studying the dipole moment in somatosensory evoked fields: a preliminary study.

OBJECTIVE: To establish a simple method of determining the appropriate stimulus intensity for studying the dipole moment in somatosensory evoked fields. METHODS: In 17 patients (20 hemispheres), the authors studied the relationship between the dipole moment and stimulus intensity, which was quantified using the threshold of thenar muscle twitch (TMT). The dipole moment was measured at 1.0, 1.5 and 2.0 TMT. Two measurements were obtained at 1.5 TMT to determine the procedure's margin of error. RESULTS: There was no significant difference between the dipole moments measured at 1.5 and 2.0 TMT. CONCLUSIONS: Setting the stimulus intensity at 1.5 TMT or more ensures a consistent response.

Aged↗
PubMed1999

Urinary bile alcohol profile in infants with intrahepatic cholestasis: identification of 5beta-cholestane-3alpha,7alpha,24,25-tetrol.

Urinary bile acids and bile alcohols were examined in six infants aged between 1 and 6 mo who had intrahepatic cholestasis. Following extraction, hydrolysis and solvolysis, cholanoids were analysed by gas-liquid chromatography and gas-liquid chromatography-mass spectrometry. The relative ratio of the urinary excretion of bile alcohols to bile acids was very low (0.07-0.22) in three patients with mild to severe cholestasis, whereas the urinary excretion of bile alcohols was 2-4 times greater than that of the total bile acids in three patients with slight cholestasis. The urinary bile alcohol spectrum in infants appears to be quite different from that in adults. Although the major bile alcohol was 27-nor-5beta-cholestane-3alpha,7alpha,12alpha,24 ,25-pentol, comprising more than 50% of total urinary bile alcohols in healthy adults, it accounted for only 35% of total urinary bile alcohols in our patients. In addition, bile alcohols carrying chenodeoxycholic acid type nucleus were detected in our patients by comparison of the retention times and mass spectra with those of authentic standards. The presence of 5beta-cholestane-3alpha,7alpha,24,25-tetrol confirmed for the first time in this study may represent an alternative pathway for chenodeoxycholic acid biosynthesis via a "25-hydroxylation pathway" in early life.

Adult↗
PubMed1999

Asymmetric reduction of ethyl 2-methyl 3-oxobutanoate by Chlorella.

Chlorella pyrenoidosa Chick reduced ethyl 2-methyl 3-oxobutanoate to the corresponding alcohols with the diastereomer (anti/syn) ratio of 53/47. The enantiomer excesses of anti-(2S, 3S)- and syn-(2S, 3R)-hydroxy esters were 89 and > 99ee% respectively. C. vulgaris and C. regularis afforded predominantly the syn-isomer, contrary to C. pyrenoidosa. The differences in the activity of reducing ethyl 2-methyl 3-oxobutanoate were observed among three strains of Chlorella. Addition of 2% metal salts slightly increased the chemical yield of the hydroxy ester.

Butyrates↗
PubMed1998

Correlation between genetic and cytogenetic maps of the rat.

To correlate rat genetic linkage maps with cytogenetic maps, we localized 25 new cosmid-derived simple sequence length polymorphism (SSLP) markers and 14 existing genetic markers on cytogenetic bands of chromosomes, using fluorescence in situ hybridization (FISH). Next, a total of 58 anchor loci, consisting of the 39 new and 19 previously reported ones, were integrated into the genetic linkage maps. Since most of the new anchor loci were developed to be localized near the terminals of the genetic or cytogenetic maps for each chromosome, the orientation and coverage of the whole genetic linkage maps were determined or confirmed with respect to the cytogenetic maps. Thus, we provide here a new base for rat genetic maps.

Animals↗
PubMed1998

Linkage mapping of the Bra, Brb and Brg genes for rat protein phosphatase 2A 55 kDa B-regulatory subunit isotypes.

We previously identified the rat Bra, Brb and Brg genes, which encode alpha, beta and gamma isotypes of the 55 kDa B-regulatory subunit of protein phosphatase 2A. Polymerase chain reaction-single strand conformation polymorphism analysis in the present study identified polymorphisms in Bra, Brb and Brg between the ACI and BUF, ZI and TM, and BN and WTC strains, respectively. Linkage analysis using mapping panels composed of F2 or back-crosses of these strains allowed Bra, Brb and Brg to be assigned to chromosomes 15, 18 and 14, respectively. Furthermore, it was revealed that Bra is located close to the Rb1 locus. Using polymorphism in Bra, loss of heterozygosity (LOH) was analyzed for rat mammary tumors induced in (SD x F344) F1 female rats by a food-borne carcinogen, 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine, and a typical mammary carcinogen, 7,12-dimethylbenz[a]anthracene. No LOH was detected at the Bra locus.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1998

Rice bifunctional alpha-amylase/subtilisin inhibitor: characterization, localization, and changes in developing and germinating seeds.

A bifunctional alpha-amylase/subtilisin inhibitor (RASI) was purified to electrophoretic homogeneity from rice (Oryza sativa L.) bran. Its molecular mass was 21 kDa by SDS-PAGE and its isoelectric point was 9.05. Purified RASI inhibited subtilisin Carlsberg strongly and inhibited alpha-amylase from germinating rice seeds weakly. It inhibited rice alpha-amylase more than barley alpha-amylase, and the inhibition of rice alpha-amylase was greater at higher pHs. RASI did not inhibit trypsin, chymotrypsin, cucumisin, or mammalian alpha-amylase. The RASI was in the outermost part of the rice grain and its subcellular site seemed to be aleurone particles in aleurone cells. SDS-PAGE and western blotting showed that RASI was synthesized in the late milky stage in developing seeds, and it remained fairly constant during the first 7 days of germination.

Blotting, Western↗
PubMed1998

A comparative genetic map of rat, mouse and human genomes.

The increasing availability of molecular markers and the development of highly efficient gene mapping strategies for the mouse, rat and human genomes have generated vast quantities of information allowing for the progressive refinement of comparative maps. In this publication we report on an updated version of our rat/mouse/human comparative genetic map, based on the mouse map. Databases for mouse, rat and human gene mapping were used for the collection of homologs mapped in the species. The comparative map was constructed with a total of 1,235 mouse loci having known homologs in the rat and/or human: 16 having homologs only in the rat, 884 having only in the human and 335 both in the rat and human. The combined length of the segments conserved between the rat and mouse spans 758 cM on the mouse map. This indicates that about 47% of the mouse genome is now covered by known rat homologous regions. Five novel regions homologous for the rat and mouse were identified. This comparative genetic map should be useful for researchers working on genetic studies in the rat, mouse and human.

Animals↗
PubMed1998

Production of WTC.ZI-zi rat congenic strain and its pathological and genetic analyses.

A new rat congenic strain, WTC.ZI-zi, was produced after eleven generations of backcrossing between ZI strain as a donor strain and WTC strain as an inbred partner. WTC.ZI-zi/zi homozygous rats generally exhibit more conspicuous body tremor and much earlier occurrence of flaccid paresis than the original ZI strain. The average life span of the congenic strain is approximately nine months, which is also much shorter than that of the original ZI strain. Pathological analysis of the central nervous system of the congenic strain revealed more aggravated vacuolation and hypomyelination than in the original ZI strain. Establishment of the genetic profile with microsatellite markers showed that the congenic strain was genetically almost identical to the WTC strain except for a small chromosome segment bearing the zitter gene. Analysis of markers in this region implied that the length of the donor segment was approximately 13.4 centimorgans which corresponded to 0.65% of the total genome. Thus, these results suggested that expressional alterations of zitter gene were due to replacement of the genetic background from the original ZI strain to the WTC strain. Furthermore, the WTC.ZI-zi congenic strain could provide a refined tool for the analysis of zitter mutation, because the congenic strain has a strict control strain, WTC, and the length of the donor chromosome is genetically defined.

Animals↗
PubMed1998

Extension of conserved regions in the rat and mouse genomes by chromosomal assignments of 29 rat genes.

We recently constructed a comparative genetic map of the rat, mouse and human genomes based on information obtained from several databases. In this study, we performed chromosomal assignments of 29 rat genes with somatic cell hybrid clones, in order to clarify and extend the conserved regions in the rat and mouse genomes. As a result, the conserved regions were extended by 89 cM. Together with our previous report, the length of the conserved regions in the rat and mouse spans 847 cM on the mouse linkage map, indicating that 53% of the mouse genome is covered by homologous regions in the rat. In addition, four conserved regions were newly revealed. The method described in this study appears to be simple and efficient for constructing a whole genome comparative map of the rat and mouse.

Animals↗
PubMed1998

[A case of crushing head injury with bilateral abducens and facial nerve palsies].

A 20-year-old male was admitted to our hospital suffering from a crushing head injury. At accident, his head had been compressed by the printing machine on both temporal regions. He remained at dull conscious. On admission one hour after the injury, he showed bilateral sixth-nerve and seventh nerve palsies and bleeding from the nose. CT scan showed marked pneumocephalus, traumatic subarachnoid hemorrhage, fluid collections in the bilateral sphenoid sinuses and right mastoid air cells. Bone CT disclosed bilateral temporal bone fractures. MRI did not show cerebral parenchymal damage. He recovered fully conscious at four hours after the injury, but cranial nerve palsies sustained over 30 days after the injury. Bilateral decompression of the facial canal were performed at day 31. At one year after the injury, bilateral abducens nerve palsies and facial nerve palsies recovered incompletely (grade III). The case report and the mechanism of such cranial nerve injuries by low-velocity crushing head injury is described.

Abducens Nerve↗
PubMed1997

Analysis of expression of lymphocyte homing-related adhesion molecules in ALY mice deficient in lymph nodes and Peyer's patches.

The aly, alymphoplasia, is an autosomal recessive mutation in mice of an unknown etiology, which induces total aplasia of lymph nodes and Peyer's patches. We hypothesized that the lack of lymphoid tissue may be due to abnormalities of lymphocyte traffic into these tissues. Therefore, we analyzed the expression of various adhesion molecules associated with lymphocyte homing. Among the adhesion molecules examined, all were normally expressed except the mucosal addressin MAdCAM-1. In aly/aly mice MAdCAM-1 was absent in the spleen at mRNA and protein levels, but was normally expressed in the intestinal venules. The FISH analysis and linkage analysis using microsatellite markers demonstrated that the MAdCAM-1 gene is located on chromosome 10, indicating that MAdCAM-1 is not encoded by the aly gene, which is located on chromosome 11. Our results indicate that the aberrant expression of MAdCAM-1 is not the direct cause of aly mutation but rather a secondary defect.

Animals↗
PubMed1997

HLA class-I-restricted and tumor-specific CTL in tumor-infiltrating lymphocytes of patients with gastric cancer.

Immune recognition of human cancers except melanoma is not well understood at either the cellular or the molecular level. We demonstrate in this study the existence of HLA class-I-restricted and tumor-specific CTL in IL-2-activated TIL (tumor-infiltrating lymphocytes) of all 4 gastric cancer patients tested. We established HLA A2-restricted and adenocarcinoma-specific CTL in 2 HLA A0201+ patients, and HLA A2402-restricted CTL recognizing both adenocarcinoma and squamous-cell carcinomas (SCC) in the 2 remaining HLA A2402+ patients. Further, HLA A3101-restricted and adenocarcinoma-specific CTL were established in 1 of the 2 HLA A2402+ patients who had HLA A3101 allele. HLA A2-, A2402- and A3101-restricted CD8+ CTL clones were established from these parental CTL lines. The 2 HLA A2-restricted CTL lines lysed 8 of 13 HLA A2+ adenocarcinoma cell lines established from different organs (stomach, colon, lung and breast) with different subtypes (HLA A0201, A0206 and A0207). The HLA A2-restricted CTL line recognized 9 and 6 different HPLC fractions of peptides eluted from the HLA A0201+ breast and HLA A0201+ colon adenocarcinoma cell lines, respectively. Allele-specific deletion of HLA A2 or A24 molecules was observed in some tumor lines that were not susceptible to lysis by the CTL lines. These results suggest that TIL of gastric cancer possess CTL recognizing different peptide antigens binding to different HLA-A alleles that are widely expressed on adenocarcinomas and also, to some extent, on SCC from different organs.

Adenocarcinoma↗
PubMed1997

Expression of MAGE genes in osteosarcoma.

Expression of MAGE genes that encode tumor-rejection antigens recognized by cytotoxic T lymphocytes with major histocompatibility complex class-I antigens was investigated in human osteosarcomas (20 cell lines and eight fresh tumor tissues). MAGE-1, 2, 3, 4, and 6 genes were expressed at the mRNA level in 11 (52.4%), 10 (47.6%), 10 (47.6%) one (4.8%), and 10 (47.6%) of 21 tumor cell lines, respectively, and in five (62.5%), six (75%), five (62.5%), one (12.5%), and five (62.5%) of eight fresh tumor tissues as determined by the reverse transcription-polymerase chain reaction method. MAGE-1 or 4 protein was detected by immunoblot analysis in eight of 11 or one of one tumor cell lines, respectively, where it was expressed at the mRNA level. Major histocompatibility complex class-I antigens were expressed in 19 of 21 tumor cell lines. These results suggest that MAGE tumor-rejection antigens are expressed in substantial numbers of osteosarcomas in a major histocompatibility class-I-restricted manner.

Antigens, Neoplasm↗
PubMed1997

Comparative studies on omega-hydroxylation of 5 beta-cholestane-3 alpha, 7 alpha, 12 alpha-triol in the mitochondrial and microsomal fraction of the liver from several vertebrates.

The activity and the stereospecificity of omega-hydroxylation, a hydroxylation at one of the two terminal methyl groups of 5 beta-cholestane-3 alpha, 7 alpha, 12 alpha-triol, which is thought to be the first step in side-chain degradation resulting in the formation of cholic acid, was elucidated in mitochondria and microsomes of the liver from several evolutionarily primitive vertebrates, fish, frogs, turtles, and chickens in addition to such mammals as rats. hamsters, and rabbits. The detection of omega-hydroxylation products (25R)- and (25S)-5 beta-cholestane-3 alpha, 7 alpha, 12 alpha, 26-tetrols as well as the separation of their two isomers was facilitated using high-performance liquid chromatography after conversion to 9-anthroyl derivatives. All the mammals examined, except for the rat, exhibited predominant activity in the mitochondrial fraction. Although the hydroxylation activity was somewhat lower in the primitive vertebrates, it was present in the mitochondria more than in the microsomes. Furthermore, the stereospecific formation of a 25R-isomer was detected in the mitochondrial fraction of most animals estimated. However, activity in the carp liver was seven times higher in the microsomes than in the mitochondria, and the hydroxylation product was almost always a 25R-isomer. Omega-Hydroxylation activity could not be detected in rainbow trout, suggesting the existence of another biosynthetic pathway, not via 26-hydroxylation, as in the 25-hydroxylation pathway, for the production of bile acid.

Animals↗