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S Tabata

Publications and source records attributed to S Tabata.

At least 145 records · Page 8Linked to original sources
PubMed1995

Meiosis specific transcription and functional proteins.

We have discussed and/or demonstrated the following: 1. Many enzymes and structural proteins have been identified as meiosis-specific proteins. These can be classified according to their metabolic behavior. 2. We obtained and analyzed 18 cDNA clones from lily meiocytes. One of them, LIM15, was similar to known genes like RecA, RAD57, and DMC1/ISC2, and might function in pairing and recombination. 3. Transcription of these genes is regulated by their regulator region(s). When such a regulator, mei2 promoter sequence isolated from S. pombe, was ligated with the proper vector and transfected, it functioned specifically in meiotic cells but not in the somatic cells tested. 4. Presence of a new lamin, lamin B3 was identified in mammalian spermatocytes and the transfection of lamin B3 gene (inserted into vector) into somatic cells alters the nuclear shape, possibly expressing a characteristic shape of meiotic nuclei. Lamin B3 was synthesized after meiosis-specific processing of lamin B2 mRNA. Other protein specific to meiotic nuclear-skeleton (MNS1) were found and characterized. All these events were studied basically focussing on homologous pairing and recombination which take place in meiosis I. We recognize the necessity of further studies on these and other events like the structure and segregation of chromosomes and the suppression of somatic gene expression during meiosis.

Amino Acid Sequence↗
PubMed1995

Adult T-cell leukemia with multiple lymphomatous polyposis of the gastrointestinal tract.

A rare case of adult T-cell leukemia (ATL) in which multiple lymphomatous polyposis (MLP) was revealed throughout the entire gastrointestinal tract is reported here. The polypectomy specimens taken from the rectum revealed infiltration of neoplastic T-cells, the integration of HTLV-1 proviral DNA, and increased CD4 (OKT4) and CD25 (IL-2R) cells. The analysis of surface markers of the lymphocytes from polypoid lesions may be useful for elucidating cell tropism and homing properties in the gastrointestinal tract. Although MLP has always been associated with B-cell lymphoma in the Western world, it is important for clinicians and pathologists to be aware that MLP may be caused by the infiltration of ATL cells.

Adult↗
PubMed1995

Two-stage bronchoplasty for synchronous contralateral lung cancers.

A 62-year-old male with two synchronous squamous-cell carcinoma was successfully treated in two stages by right upper sleeve lobectomy and left S6 sleeve segmentectomy. The patient remains well without recurrence two years after surgery. Bronchoplastic surgery is an effective approach for multicentric hilar cancers with poor pulmonary function.

Bronchi↗
PubMed1995

A case of iatrogenic growth retardation induced by a corticosteroid-containing anti-allergic drug.

A nine-year old boy developed reduced growth velocity at the age of seven. The peak plasma growth hormone (GH) response to 3,4-dihydroxyphenylalanine, GH-releasing factor and insulin was 10.2, 8.1 and 7.6 micrograms/l, respectively, suggesting that the GH reserve was slightly reduced. Serum cortisol was undetectable and urinary excretion of 17-hydroxycorticosteroid was low (0.22-0.31 mg/day), but there were no physical or biochemical signs of adrenocortical insufficiency. He had taken an anti-allergic drug containing 0.25 mg of betamethasone and 2 mg of d-chlorpheniramine maleate per tablet for about 2 years to treat allergic rhinitis. Catch-up growth occurred when this drug was stopped. The present case suggests that daily administration of 0.25 mg of betamethasone can induce growth retardation and that ingestion of corticosteroid-containing preparations needs to be excluded in children who develop short stature without other symptoms.

17-Hydroxycorticosteroids↗
PubMed1995

Prediction of the coding sequences of unidentified human genes. III. The coding sequences of 40 new genes (KIAA0081-KIAA0120) deduced by analysis of cDNA clones from human cell line KG-1.

We isolated full-length cDNA clones from size-fractionated cDNA libraries of human immature myeloid cell line KG-1, and the coding sequences of 40 genes were newly predicted. A computer search of the GenBank/EMBL databases indicated that the sequences of 14 genes were unrelated to any reported genes, while the remaining 26 genes carried some sequences with similarities to known genes. Significant transmembrane domains were identified in 17 genes, and protein motifs that matched those in the PROSITE motif database were identified in 11 genes. Northern hybridization analysis with 18 different cells and tissues demonstrated that 10 genes were apparently expressed in a cell-specific or tissue-specific manner. Among the genes predicted, half were isolated from the medium-sized cDNA library and the other half from the small-sized cDNA library, and their average sizes were 4 kb and 1.4 kb, respectively. As judged by Northern hybridization profiles, small-sized cDNAs appeared to be expressed more ubiquitously and abundantly in various tissues, compared with that of medium-sized cDNAs.

Cell Line↗
PubMed1995

Structural analysis of a recA-like gene in the genome of Arabidopsis thaliana.

A recA-like gene was identified in the genome of Arabidopsis thaliana by means of PCR using primers designed on the basis of previously reported amino acid sequences of eukaryotic RecA-like proteins. The structure of the gene, termed ArLIM15, was investigated by comparing the primary structure of the genomic DNA with that of the corresponding cDNA. The open reading frame, which was split into 15 exons, was established to have the capacity for encoding a 37.3-kDa polypeptide. The amino acid sequence of the putative product of ArLIM15 showed a high degree of similarity to that of LIM15 in the monocotyledonous plant Lilium, including a 93% identity, and to those of other recA-like genes in yeasts and vertebrates with identities of 69-71%. Phylogenetic analysis indicated ArLIM15 to be much closer to meiosis-specific LIM15 and DMC1 in Saccharomyces cerevisiae than to RAD51 in S. cerevisiae and its homologues on an evolutionary scale.

Amino Acid Sequence↗
PubMed1995

Collagen fibrils in the odontoblast layer in the teeth of the rat and the house shrew, Suncus murinus, by scanning electron microscopy using a maceration method.

It is not well known whether there are gaps in the tight junctions between odontoblasts and whether the fluid flows from the pulp to the predentin through these gaps. The collagen fibrils in the odontoblast layer were investigated using a maceration method in order to show the existence of the gaps between tight junctions of the odontoblasts. The mandibles containing teeth of the rat and the house shrew were digested by NaOH maceration and revealed the architecture of the collagen fibrils under scanning electron microscopy. The collagen fibrils went from the pulp, through the odontoblast layer, and were woven into the collagen network of the predentin in all teeth used in this study. Thick bundles of collagen were seen in the odontoblast layer at the pulp horn of the rat molars. Because there are many collagen fibrils in the odontoblast layer, it is considered that the tight junction of the odontoblast is of the discontinuous type.

Alveolar Process↗
PubMed1995

IgE-mediated allergy to spider mite, Panonychus citri in occupationally exposed individuals.

This paper is the first report on allergy caused by a spider mite, Panonychus citri. Some of fruitgrowers cultivating Citrus junos were manifested immediate allergic symptoms by farming, especially by harvest. By examining C. junos trees, we found the trees cultivated by the fruitgrowers were infested with P. citri. Twelve subjects complaining of immediate allergic symptoms were examined by intradermal test and RAST using allergen extracts prepared from P. citri and Dermatophagoides spp. In intradermal test, ten out of twelve showed a positive response to P. citri and twelve positive to D. farinae. Positive RAST to P. citri were obtained in seven of twelve. Six of them also had positive RAST to D. farinae and D. pteronyssinus. In ELISA inhibition using a serum from Case 4, the inhibition with P. citri extract reached to 92% at the highest concentration used but at the same concentration D. farinae and D. pteronyssinus extracts did not inhibit the binding of specific IgE antibodies to allergen of P. citri. In Case 7, the extracts of P. citri, D. farinae and D. pteronyssinus inhibited at the same concentration 94%, 81%, and 87%, respectively. These results lead to the following conclusions: Seven subjects positive to P. citri in intradermal test and RAST are sensitized to P. citri. P. citri has a specific allergenic determinant in addition to a common determinant with Dermatophagoides spp.

Adult↗
PubMed1994

Collagen fibrils in the odontoblast layer of the rat incisor by scanning electron microscopy using the maceration method.

BACKGROUND: There is not universal agreement on the existence of the extracellular pathway from the pulp along the odontoblast layer to the predentin. METHOD: To confirm this pathway, the architecture of collagen fibrils in the rat incisor dentin and pulp, especially in the odontoblast layer of the lateral (periodontal ligament) sides of the tooth, was demonstrated in the present investigation using scanning electron microscopy of the maceration method for collagen networks. RESULTS: Numerous collagen bundles were observed in the odontoblast layer in the mature odontoblast region which, except for the young odontoblast region, comprises the major portion of the incisor. The collagen bundles went from the pulp, through the odontoblast layer, and were woven into the collagen network of the predentin. The meshwork structure was composed of fine secondary fibrils among these collagen bundles. The surface of the predentin contained many oval-shaped holes which were surrounded by collagen fibrils. Fracturing the dentin longitudinally relative to the dentinal tubules revealed that the arrangement of the collagen fibrils at the surface of the tubules was either circular or oblique. In the young odontoblast region, i.e., the thin portion from the apical end of the incisor where the mineralization of the dentin does not occur and where the height of the odontoblasts was less than 30 microns, many thick bundles composed of thick collagen fibrils ran straight from the pulp to the predentin through the odontoblast layer and fanned out in the collagen network of the predentin. These thick bundles might correspond to the so-called "von Korff fibers." The distribution of collagen fibrils in the pulp was random except on the surface of the blood vessels where the fibrils comprised two sheets of collagen: the inner sheet which coursed longitudinally to the long axis of the vessel, and the outer sheet which ran transversely. CONCLUSION: It was considered that the fluid in the pulp could flow to the predentin along the collagen fibrils through the tight junction between the odontoblasts.

Animals↗
PubMed1994

Identification and characterization of genes induced during sexual differentiation in Schizosaccharomyces pombe.

Five cDNA clones, harboring genetic messages preferentially expressed during the sexual differentiation process, were isolated from a cDNA library of Schizosaccharomyces pombe by subtractive screening. Transcription of the corresponding genes, termed isp3, 4, 5, 6, and 7, was dependent on nitrogen starvation and their induction occurred at several stages of spore formation. Analysis of the cDNA primary structures revealed a capacity for the coding of polypeptides of 19.2 kDa, 88.3 kDa, 60.1 kDa, 49.7 kDa, and 43.8 kDa, respectively. The translated amino-acid sequences of isp5 and isp6 were found to show significant similarities to those of amino-acid permeases and proteinase B of Saccharomyces cerevisiae, respectively. Disruption of isp6 arrested the cell cycle prior to conjugation and caused a drastic blocking effect on spore formation.

Amino Acid Sequence↗
PubMed1994

cDNA cloning and functional characterization of a meiosis-specific protein (MNS1) with apparent nuclear association.

It is well known that cytoskeleton and karyoskeleton proteins are associated with changes in cell shape and with the rearrangement of the dynamic structures involved in cell division and motility. In higher vertebrates, there are three major skeletal protein groups: microfilaments, microtubules and intermediate filaments, each representing a multigene family. Some of these skeletal proteins are expressed in a temporally- and spatially-specific fashion, and they establish cell-specific cytoplasmic and nucleoplasmic organization during development. Here we report the cDNA cloning of a novel 60 kDa skeletal protein from mouse spermatocytes, termed MNS 1 (meiosis-specific nuclear structural protein), whose computer-predicted protein configuration indicates long alpha-helical coiled-coil domains flanked by non-helical terminal domains. Functional characterization of MNS1 by ectopic expression in culture cells indicated that it is a detergent- and high salt-resistant skeletal protein which is involved in organization of the nuclear or perinuclear architecture. The MNS1 protein is specifically expressed at the pachytene stage during spermatogenesis, so that its function may involve the determination and maintenance of the appropriate nuclear morphology during meiotic prophase.

Amino Acid Sequence↗
PubMed1994

Susceptibility of ebiratide to proteolysis in rat intestinal fluid and homogenates and its protection by various protease inhibitors.

In order to estimate the intestinal stability of ebiratide [H-Met(O2)-Glu-His-Phe-D-Lys-Phe-NH(CH2)8-NH2], a novel adrenocorticotropic hormone (ACTH) analogue, after oral administration, the hydrolytic properties of ebiratide were determined in the rat small intestinal fluid and mucosal homogenates. Ebiratide was extremely stable in the rat small intestinal fluid, while it was degraded in various intestinal mucosal homogenates. Regional differences were observed in its proteolytic properties; e.g., the hydrolytic rates of ebiratide in jejunal and ileal mucosal homogenates were 2-3 times faster than that in duodenal and colonic homogenates. Degradation of ebiratide was markedly inhibited by aminoprotease inhibitors such as sodium glycocholate, puromycin, bestatin and bacitracin. These results suggest that co-administration of certain protease inhibitors are useful to improve the stability of ebiratide in the intestine.

Adrenocorticotropic Hormone↗
PubMed1994

Characterization of cDNAs induced in meiotic prophase in lily microsporocytes.

To identify and analyze genes functioning during reproductive cell formation in higher plants, cDNAs harboring the messages induced in meiotic prophase were isolated and characterized. A cDNA library constructed from microsporocytes in meiotic prophase of Lilium longiflorum was screened with a subtraction probe specific to meiotic prophase. Clones selected were classified into 18 groups by cross hybridization and partial sequencing. Northern blot analysis revealed that the transcripts corresponding to the respective cDNA groups began accumulating at the early stages of meiosis and exhibited clone-specific profiles during meiosis and the spore formation process. The amino acid sequences of the predicted gene products showed similarity with known gene products, e.g. heat shock proteins, serine proteases in Bacillus, and RAD 51 gene product in yeast. Half of the putative gene products had hydrophobic N-terminal regions, suggesting that they may function as signal peptides.

Amino Acid Sequence↗
PubMed1994

Prediction of the coding sequences of unidentified human genes. I. The coding sequences of 40 new genes (KIAA0001-KIAA0040) deduced by analysis of randomly sampled cDNA clones from human immature myeloid cell line KG-1.

We established a protocol for the prediction of the coding sequences of unidentified human genes based on the double selection and sequence analysis of cDNA clones with inserts carrying unreported 5'-terminal sequences and with insert sizes corresponding to nearly full-length transcripts. By applying the protocol, cDNA clones with inserts longer than 2 kb were isolated from a cDNA library of human immature myeloid cell line KG-1, and the coding sequences of 40 new genes were predicted. A computer search of the sequences indicated that 20 genes contained sequences similar to known genes in the GenBank/EMBL databases. The sequences of the remaining 20 genes were entirely new, and characteristic protein motifs or domains were identified in 32 genes. Other sequence features noted were that the coding sequences of 23 genes were followed by relatively long stretches of 3'-untranslated sequences and that 5 genes contained repetitive sequences in their 3'-untranslated regions. The chromosomal location of these genes has been determined. By increasing the scale of the above analysis, the coding sequences of many unidentified genes can be predicted.

Base Sequence↗
PubMed1994

Prediction of the coding sequences of unidentified human genes. II. The coding sequences of 40 new genes (KIAA0041-KIAA0080) deduced by analysis of cDNA clones from human cell line KG-1.

By applying the protocol previously established, we isolated and sequenced full-length cDNA clones longer than 2 kb from cDNA library of human immature myeloid cell line KG-1, and the coding sequences of 40 new genes were predicted. A computer search of the sequences indicated that 29 genes contained sequences with similarities to reported genes in the GenBank/EMBL databases. Significant transmembrane domains were identified in 9 genes, 5 of which harbored multiple hydrophobic regions. Protein motifs that matched those in the PROSITE motif database were identified in 13 genes. In terms of sequence similarities and protein motifs, 5 genes were related to transcriptional factors. Repetitive sequences were found in the 3'-untranslated region of 8 genes. Northern hybridization demonstrated that the expression of 9 genes was tissue-specific, while the remaining 31 genes were expressed ubiquitously. It was also noted that 17 genes yielded different sizes of bands possibly due to either alternative splicing or alternative initiation. The chromosomal location of these genes has been determined.

Amino Acid Sequence↗