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S Tabata

Publications and source records attributed to S Tabata.

At least 163 records · Page 9Linked to original sources
PubMed1994

A physical map of the genome of a unicellular cyanobacterium Synechocystis sp. strain PCC6803.

An accurate physical map of the genome of a cyanobacterium, Synechocystis sp. strain PCC6803, was constructed on the basis of restriction and linking clone analysis. The genome contained 6 recognition sites for AscI, 25 sites for MluI, and 31 sites for SplI, and the entire genome size was estimated to be 3.6 Mb. Sixteen genes or gene clusters, including those involved in the photosynthetic systems, were localized on the physical map of the genome by hybridization. In the course of the above analysis, two extra chromosomal units with approximate sizes of 110 kb and 125 kb were identified.

Chromosome Mapping↗
PubMed1994

[Immunocytochemistry in the diagnosis of acute myeloid leukemia (M0)].

We examined leukemic blasts from 5 cases of AML-M0 diagnosed according to The French-American-British (FAB) classification for expression of immunological markers as well as myeloperoxidase (MPO) using flow cytometry (FCM) and immunocytochemistry (ICC). In one patient, the myeloid antigens, CD13 and CD33, were negative on FCM, but apparently positive in the cytoplasm by ICC, leading to a diagnosis of AML-M0. We examined MPO with anti-MPO monoclonal antibody in four patients by ICC, and could detect 3% or more MPO positive rates in all cases. These findings indicate that immunological studies for MPO and myeloid markers using ICC are very useful for the diagnosis of AML-M0. Two of 5 patients achieved CR, but they relapsed soon or after one year, respectively. The treatment outcomes suggest that the AML-M0 is an AML subtype with poor prognosis.

Adolescent↗
PubMed1994

[Treatments for advanced transitional cell carcinoma of the urinary tract: chemotherapy and operation].

The current status of treatments for advanced transitional cell carcinoma of the urinary tract with metastasis is reported. A total of 62 patients were treated in Nara Medical University Hospital and its affiliated hospitals between January, 1980 and June, 1993. All patients were divided into two categories; cases in which local recurrence and/or distant metastasis had developed during the followup study (group 1) (n = 32) and fresh cases with distant metastasis (group 2) (n = 30). Most of the metastatic sites were treated with chemotherapy alone or combination therapy including chemotherapy. As for clinical response of each case, CR + PR rate in group 1 (34%) was higher than that in group 2 (13%) (p < 0.1). As for prognosis, the survival rate in group 1 was significantly higher than that in group 2 (p < 0.05). In group 1, the survival of CR was significantly higher than that of the non-responders. No adjuvant therapy for invasive bladder cancer and post-operative adjuvant therapy for renal pelvic and/or ureteral cancer can be recommended to prevent local recurrence or distant metastasis. In addition, supporting therapy and dose intensified chemotherapy would lead to good prognosis in advanced urothelial cancer patients.

Adult↗
PubMed1994

[Percutaneous renal cyst puncture with CO2 instillation therapy].

Ultrasound-guided percutaneous puncture of renal cysts replaced by CO2 was performed on 9 renal cysts of 6 patients from May 1993 through September 1993. Puncture and aspiration of cysts was performed using a 5.5 Fr one-step fluid drain kit (pig tail stent) under ultrasonography inspection. Aspirated volume of cyst contents was 15-292ml (mean 115 ml), and the instilled CO2 volume was 15-150 ml (mean 73 ml). All patients were checked by CT scan. In one month, the reduction rate of cyst volume was 46-84% (mean 69%) and lumbago, their chief complaint, was improved in all patients. No complications were observed in patients treated by CO2 instillation. Although long-term followup is needed to draw a definite conclusion, this therapy may be useful for benign renal cystic lesions.

Aged↗
PubMed1994

[Lung 3H-thymidine incorporation in monocrotaline (MCT)-treated rats--role of platelet-activating factor (PAF)].

Monocrotaline (MCT) causes chronic pulmonary hypertension associated with pulmonary vascular thickening in rats. Since components of the pulmonary vascular thickening are reflected in increased DNA synthesis in medial smooth muscle cells, and since platelet-activating factor (PAF) has been reported to contribute to the pulmonary hypertension induced by MCT, we examined the effect of WEB 2170, a specific PAF receptor blocker, on MCT-induced pulmonary vascular thickening and in vitro 3H-thymidine incorporation into lung tissue, as an index of stimulation of cell proliferation. In MCT-treated rats, pulmonary hypertension, right ventricular hypertrophy, and pulmonary vascular thickening developed at 3 weeks after injection. Also, in MCT-treated rat lung tissue, there was a significant increase in the in vitro 3H-thymidine incorporation rate. In WEB 2170-treated MCT rats, these changes were significantly less severe than those observed in rats receiving MCT alone. We conclude that PAF plays a role in the inflammatory process that contributes to the development of pulmonary hypertension and vascular remodeling associated with increased lung cell proliferation in MCT-treated rats.

Animals↗
PubMed1994

Identification of human DAN gene, mapping to the putative neuroblastoma tumor suppressor locus.

The expression of DAN gene (previously designated as N03 gene) is significantly reduced in a variety of transformed rat fibroblasts, including v-src- (SR-3Y1), SV40- and v-mos-transformed 3Y1 cells, compared with that in parental 3Y1 cells. Recently, DAN gene has been shown to possess a tumor suppressive activity when it is overexpressed in SR-3Y1 cells (Ozaki & Sakiyama, 1994). To assess the involvement of DAN gene with human neoplasms, we have isolated human DAN counterpart from a normal lung cDNA library by using rat DAN cDNA as a probe, and determined its chromosomal location. Human DAN gene mapped to chromosome 1p36.11-p36.13, which is well known to show highly significant linkage with the genesis and/or progression of human neuroblastoma. Southern blot analysis on tumor DNA from 26 patients with neuroblastoma has detected three patients showing genomic rearrangement or deletion within or closely linked to the DAN gene locus. Collectively, we propose that human DAN gene is a possible candidate for a tumor suppressor gene of human neuroblastoma.

Amino Acid Sequence↗
PubMed1994

[Treatment of acute lymphoblastic leukemia in adults by the modified protocol of L-10M (Sloan-Kettering): long-term outcome].

From January 1984 to April 1988, we treated 20 patients with adult lymphoblastic leukemia (ALL) and 2 patients with lymphoblastic lymphoma with a protocol which we modified L-10M of Sloan-Kettering Cancer Center. Since the median follow up time is now over 5 years, we report the most recent outcome. Thirteen patients were male and 9 were female. The median age was 31, ranging from 15 to 71 years of age, and there were no Ph1 positive patients. The complete remission (CR) rate was 81.8%. Median CR duration was 32 months and the 5-year continuous CR rate was 33.3%. No significant prognostic factor for CR rate was found. Age at achievement CR and duration were significant prognostic factors. The 5-year continuous CR rate of patients below 35 years old was 54.5%. In this group the leukocyte count was a significant prognostic factor. All patients with a leukocyte count above 1 x 10(4)/microliters relapsed. However, in patients with a WBC below 1 x 10(4)/microliters, the 5-year continuous CR rate was 75%. Based on these results, it seems reasonable to treat patients with ALL by different therapeutic strategies according to the risk factors.

Adolescent↗
PubMed1993

Isolation and characterization of a novel member of the gene family encoding the cAMP response element-binding protein CRE-BP1.

Among multiple CRE (cyclic AMP response element)-binding proteins, CRE-BP1 (also designated ATF-2) has two unique characteristics: it mediates the adenovirus E1A-induced trans-activation and forms a heterodimer with c-Jun. Two structures, a putative metal finger and a leucine zipper, in CRE-BP1 are responsible for these capacities. As a new member of a CRE-BP1 family that has similar metal finger and leucine zipper structures, we have isolated cDNA clones of CRE-BPa by cross-hybridization with CRE-BP1 cDNA. CRE-BPa protein consists of 508 amino acids and has a molecular weight of 56,840. CRE-BPa protein is highly homologous with CRE-BP1 in four regions: two of them are the regions containing the putative metal finger or the DNA-binding domain consisting of the basic amino acid cluster and the leucine zipper. Like CRE-BP1, CRE-BPa binds to CRE with higher affinity than to the 12-O-tetradecanoylphorbol-13-acetate response element as a homodimer or a CRE-BPa/c-Jun or CRE-BPa/CRE-BP1 heterodimer. However, using the c-Myb-CRE-BPa fusion protein, it was show that CRE-BPa could not mediate the E1A-induced trans-activation. Expression of CRE-BPa mRNA was found in a limited number of cell lines, and multiple sizes of CRE-BPa mRNA species were detected in some cell lines and tissues. CRE-BPa will be useful to clarify the mechanism of CRE-mediated transcriptional activation by E1A or c-Jun.

Activating Transcription Factor 2↗
PubMed1993

Fate of odontoblasts and blood capillaries in the incisal region of the rat incisor pulp.

Transmission electron microscopy of thin sections of the rat incisor pulp revealed that in the middle region of the incisor there were fenestrated capillaries in the "predentinal plexus" and that this region contained the tallest odontoblasts. The odontoblasts gradually became shortened in the incisal part of this region; the fenestrated capillaries in the predentinal plexus changed to continuous type capillaries. Almost all the odontoblasts had degenerated near the incisal end of the tooth. The predentinal plexus disappeared in this region, but the "subodontoblastic capillary plexus" persisted. In a specific region just beneath the worn incisal end, numerous macrophages and polymorphonuclear neutrophils appeared and scavenged the degenerating cells, possibly including the odontoblasts.

Animals↗
PubMed1993

Osteogenic differentiation of marrow stromal stem cells in porous hydroxyapatite ceramics.

Bioactive materials such as hydroxyapatite ceramics (HA) are known to show a stable interfacial bond with tissues (the bone bonding property has been especially well documented). However, the biological phenomenon on the material surface that evoke bone bonding is not well documented. To address this issue, composites of porous HA and rat marrow cells were implanted into ectopic (subcutaneous) sites. At 3 weeks after implantation, active osteoblasts lining the HA surface initiated bone formation, primarily as mature bone (lamellar type). Gene expression study using Northern blot analysis of the composites showed that alkaline phosphatase (ALP) and bone Gla protein (BGP) mRNAs began to appear at 2 weeks and the level of BGP mRNA at 4 weeks was comparable to that of cancerous bone. However, HA implantation without marrow cells did not show bone formation and neither BGP nor ALP mRNA were detected. These results indicate that the HA surface is able to support cell differentiation (osteoblastic phenotype expression of marrow stromal stem cells), as well as cell coordination resulting in mature bone formation that bonds to the HA.

Alkaline Phosphatase↗
PubMed1993

Correlation between lack of bone Gla protein mRNA expression in rat transplantable osteosarcomas and expression of both c-fos and c-jun proto-oncogenes.

Alkaline phosphatase (AP) activity and expression of bone Gla protein (BGP), c-fos, and c-jun were compared in two transplantable osteosarcomas with high potentials for metastasis to the lung. The original spontaneous osteosarcoma (SOS) gradually became histologically undifferentiated, losing its osteogenic activity during serial transfer, whereas the chemical (4-hydroxyaminoquinoline 1-oxide)-induced osteosarcoma (COS) retained osteogenesis. The two osteosarcomas showed similar doubling times and levels of lung metastasis, and strong AP activity was detected on the cell membranes of both. Northern blot analysis revealed that lack of BGP mRNA expression was associated with expression of both c-fos and c-jun proto-oncogenes in SOS. In contrast, neither c-fos nor c-jun mRNAs were detected but BGP mRNA was expressed in the case of COS. These results suggest that the c-fos and c-jun genes may suppress the expression of BGP mRNA relevant to differentiation and osteoid formation in rat osteosarcomas. However, this does not appear to be directly related to proliferative or metastatic biological behavior.

Alkaline Phosphatase↗
PubMed1993

Effect of cadmium on osteogenesis within diffusion chambers by bone marrow cells: biochemical evidence of decreased bone formation capacity.

The biological and biochemical effects of cadmium administration on bone marrow in rats were examined. When young adult rats were administered cadmium (Cd) repeatedly at a dose of 750 micrograms/kg body wt for up to 4 weeks, metallothionein mRNA was detected by a gene expression analysis in their bone marrow at 2 weeks after the first Cd administration, though the amounts were lower than those in liver. To determine the direct effect of cadmium on bone formation, the potential of Cd-treated bone marrow cells and demineralized bone matrix (DBM) to form bone and cartilage was assessed using a diffusion chamber (DC) in vivo, by histological examination, and by biochemical parameters such as alkaline phosphatase (ALP) activity, total calcium and phosphorus content, and the bone-specific vitamin K-dependent Gla-containing protein (BGP) content, relative to mineralization. Diffusion chambers were inoculated with DBM and bone marrow cells from either Cd-treated or nontreated rats (control) and were then implanted subcutaneously into syngeneic nontreated rats. The accumulation of BGP in DCs with Cd-treated bone marrow was significantly lower than that in control DCs. Unlike in control DC, a peak of ALP activity did not occur at 4 weeks postimplantation in DC implants inoculated with Cd-treated bone marrow; the ALP activity and calcium content in these implants were also significantly lower than those of the control bone marrow-containing chambers at the early stage of implantation. Histological examinations of chambers with Cd-treated marrow showed a decreased area of cartilage and bone foci compared with those in control chambers. These findings suggest that Cd administration inhibits the osteoblastic and chondroblastic differentiation pathway in bone marrow through direct effects on these cells.

Animals↗
PubMed1993

Histochemical analysis of blood group antigens in human sublingual glands and pancreas. An application of high-performance liquid chromatography to estimate the quantity of galactose liberated from tissue sections by alpha-galactosidase digestion.

Using immunostaining with monoclonal antibodies (mAbs) from three different sources as well as anti-B lectin, GSAI-B4 staining and alpha-galactosidase digestion, blood group B antigens were localized and analysed in tissue sections of sublingual glands from blood group B and AB individuals. Quantitative analysis of galactose was simultaneously carried out on the supernatant enzyme solution used for treating tissue sections by high-performance liquid chromatography (HPLC). In addition, galactose liberated from the pancreas tissues of blood group B and AB individuals was also estimated by HPLC analysis in order to compare the content of antigens. mAb-B(H079) and GSAI-B4 reacted uniformly with the mucous cells from blood group B and AB secretors. On the other hand, other mAbs-B(B006 and A582) recognized the antigen in a limited number of cells or was even negative in some cases of blood group AB individuals. Only mAb-B(H079) recognized the B antigens in mucous cells from non-secretors. Digestion with alpha-galactosidase resulted in the consistent appearance of H and Le(b) antigens in the mucous cells of all the secretors examined, although the reduction of staining intensity with anti-B reagents was not so marked. Le(y) antigens also appeared in some cases after the enzyme digestion. In non-secretors, Le(b) and Le(y) antigens, but not H antigens, appeared in some mucous cells following enzyme digestion. HPLC analysis of galactose revealed that alpha-galactosidase can specifically liberate the terminal galactose residues of B antigens, and no marked difference was present in the content of liberated galactose from mucous cells of sublingual glands among the individuals investigated (8.5-11.7 nmoles cm-2). No galactose was detected in samples from the sublingual glands of non-secretors, and only a trace amount of galactose was detected in the samples from pancreas tissues. These results suggest that the observed difference in the reactivity of different reagents with each tissue site can be ascribed to both quantitative and qualitative heterogeneity of B antigens.

Blood Group Antigens↗
PubMed1993

Isolation and characterization of a yeast gene that is homologous with a meiosis-specific cDNA from a plant.

By using as probe a meiosis-specific cDNA clone LIM15 from the monocotyledonous plant, Lilium longiflorum, a clone containing a 2.8 kb DNA fragment was isolated from a genomic library of Saccharomyces cerevisiae. Primary structure analysis revealed that the clone includes two complete open reading frames, designated ISC2 and ISC10, capable of coding for a 36.6 kDa and a 31.6 kDa polypeptide, respectively, with the former frame being interrupted by a 92 bp intron. The predicted amino acid sequence of Isc2 was 56% identical with the putative gene product of lily cDNA clone LIM15, and showed limited sequence similarity with the yeast RAD57 gene product. Transcripts of the two genes begin accumulating 2.5 h and 7.5 h after induction of meiosis, respectively, according to a Northern hybridization analysis. Since disruption of either one of these genes had a drastic effect on the ability to form spores, ISC2 and ISC10 are expected to play significant roles in the formation of reproductive cells.

Amino Acid Sequence↗
PubMed1993

Sex difference in pharmacokinetics of the novel sulfonylurea antidiabetic glimepiride in rats.

Glimepiride (Hoe 490, CAS 93479-97-1), a novel sulfonylurea antidiabetic agent, was studied for the cause of sex-related difference in the elimination clearance of the unchanged drug in rats. After intravenous and oral administration, the serum level of the unchanged drug was higher in female rats and AUC and t1/2 (beta) values were about 1.7- and 1.4-fold those for males, while Vss and oral bioavailability were nearly equal. The excretion clearance of the unchanged drug was quite small in both male and female animals, and most of the administered drug was excreted into the bile as a hydroxymethyl derivative, M1. In the in vitro metabolism study, M1 was found to be formed mainly in the liver microsomal fraction, and its hydroxylation activity was significantly higher in males. This metabolic activity was dependent on NADPH and was inhibited by proadifen. On the other hand, formation of M2, a carboxyl derivative, from M1 was observed in the cytosol fraction and showed no sex difference. Its metabolic activity depended on NAD and was inhibited by pyrazole. These results suggest that the sex difference observed in rat pharmacokinetics is mainly due to different hydroxylation activities of the side chain methyl group based on the participation of sex dependent cytochrome P-450 in liver microsomes.

Administration, Oral↗