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Biomedical subjects

N Ota

Publications and source records attributed to N Ota.

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

Isolation and radiation hybrid mapping of a highly polymorphic CA repeat sequence at the SREBP cleavage-activating protein (SCAP) locus.

Sterol regulatory element binding protein (SREBP) cleavage-activating protein (SCAP) is a central regulator of lipid synthesis and uptake in animal cells. A polymorphic dinucleotide (CA) repeat sequence was isolated from a genomic clone containing the SCAP gene and was mapped to chromosome 3p21.3. High heterozygosity (0.89) makes this polymorphism a useful marker in the genetic study of disorders affecting lipid metabolism.

CCAAT-Enhancer-Binding Proteins↗
PubMed1999

A common Ile796Val polymorphism of the human SREBP cleavage-activating protein (SCAP) gene.

We identified a new common amino acid polymorphism of isoleucine/valine at codon 796 in exon 16 of the gene for human sterol regulatory element binding protein (SREBP) cleavage-activating protein (SCAP), a central regulator of lipid synthesis and metabolism in animal cells. It can be detected as an MslI restriction fragment length polymorphism. The allelic frequencies were: isoleucine (A) allele, 0.57 and valine (G) allele, 0.43. This polymorphism may be useful for genetic studies of disorders affecting intracellular lipid metabolism and hyperlipidemia.

Humans↗
PubMed1999

Interleukin 1 beta, interleukin 6, beta 2-microglobulin, and transforming growth factor-alpha in gingival crevicular fluid from human periodontal disease.

Inflammatory mediators are central to the pathogenesis of periodontal diseases and may be used as markers in diagnosis. The aim of this study was to identify and quantify the various growth factors, apoptosis-related modifiers [soluble form of Fas (sFas) and bcl-2] and cytokines in the gingival crevicular fluid (GCF) of patients with different severities of periodontitis as compared with those of controls. GCF samples were taken from patients with periodontal disease and from controls. The concentrations of epidermal growth factor, transforming growth factor (TGF)-alpha, interleukin (IL)-1 beta, IL-6, interferon-gamma, beta 2-microglobulin (beta 2-MG), and apoptosis-related modifiers sFas and bcl-2 in the samples were determined by enzyme-linked immunosorbent assay. TGF-alpha was significantly lower in patients with periodontal disease than in the controls. In contrast, the concentrations of IL-1 beta, IL-6; and beta 2-MG were significantly higher in the group with severe periodontal disease than in the controls. The amount of total protein in the GCF was considerably higher in the disease group than the controls (p < 0.05). TGF-alpha, IL-1 beta, and beta 2-MG concentrations were associated (Spearman rank correlation, r < 0.05 for all) with clinical measures of disease severity (pocket depth) and inflammation (bleeding when probed). Apoptosis-related modifiers (sFas and bcl-2) could not be detected in any samples. These results suggest that the growth factor TGF-alpha and certain cytokines are associated with the presence of periodontal disease.

Adult↗
PubMed1999

A highly polymorphic CA repeat marker at the interleukin-11 locus.

The interleukin-11 (IL-11) stimulates T cell-dependent development of immunoglobulin-producing B cells and collaborates with IL-3 in supporting murine megakaryocyte colony formation. The interleukin-11 (IL-11) also stimulates osteoclast formation and inhibits osteoclast function in vitro and has been implicated in estrogen deficiency-induced bone loss. We isolated a polymorphic dinucleotide (CA) repeat sequence from a genomic clone containing the IL-11 gene located at 19q13.3-q13.4. High heterozygosity (0.81) makes this polymorphism a useful marker in genetic study of disorders affecting immune response and bone metabolism.

Base Sequence↗
PubMed1999

Allelic variants in the interleukin-6 gene and essential hypertension in Japanese women.

Genes that can be implicated in hypertension in experimental animals are plausible candidates in the pathogenesis of human hypertension. A recent genome-wide search for quantitative-trait loci (QTL) in hypertensive rats revealed a strong correlation between the interleukin-6 (IL-6) locus on rat chromosome 4 and systolic, diastolic, and mean arterial pressure in this mammalian species. To investigate a possible association between genetic variations of the IL-6 gene and hypertension in humans, we identified two novel single-nucleotide sequence variations, a C/G substitution at -634 in the promoter region and a G/A substitution at 4391 in a 3' non-coding portion of exon 5, and a previous reported sequence variant, an A/T variation in the composition of the AnTn tract around -447 in the promoter region (Fishman D et al. J Clin Invest 1998; 102: 1369-1376), within a test population of 96 Japanese subjects. Allelic associations involving these variations were analyzed in 150 hypertensive and 143 normotensive Japanese women. The distribution of alleles of the three polymorphisms, as well as a dinucleotide repeat present at the IL-6 locus, was similar in the two groups. Therefore, the IL-6 gene appears to play a minimal role in the genetic etiology of essential hypertension in Japanese women.

Aged↗
PubMed1998

Effects of helical structures formed by the binding arms of DNAzymes and their substrates on catalytic activity.

As a part of our efforts to clarify structure-function relationships in reactions catalyzed by deoxyribozymes (DNAzymes), which were recently selected in vitro , we synthesized various chimeras and analyzed the kinetics of the corresponding cleavage reactions. We focused on the binding arms and generated helices composed of binding arms and substrates that consisted of RNA and RNA, of RNA and DNA or of DNA and DNA. As expected for the rate limiting chemical cleavage step in reactions catalyzed by DNAzymes, a linear relationship between log( k cat) and pH was observed. In all cases examined, introduction of DNA into the binding helix enhanced the rate of chemical cleavage. Comparison of CD spectra of DNAzyme. substrate complexes suggested that higher levels of B-form-like helix were associated with higher rates of cleavage of the substrate within the complex. To our surprise, the enhancement of catalytic activity that followed introduction of DNA into the binding helix (enhancement by the presence of more B-form-like helix) was very similar to that observed in the case of the hammerhead ribozymes that we had investigated previously. These data, together with other observations, strongly suggest that the reaction mechanism of metal-ion-dependent DNAzymes is almost identical to that of hammerhead ribozymes.

Base Sequence↗
PubMed1998

Determination of interactions between structured nucleic acids by fluorescence resonance energy transfer (FRET): selection of target sites for functional nucleic acids.

We previously developed a method for monitoring the integrity of oligonucleotides in vitro and in vivo by quantitating fluorescence resonance energy transfer (FRET) between two different fluorochromes attached to a single oligonucleotide. As an extension of this analysis, we examined changes in the extent of FRET in the presence or absence of target nucleic acids with a specific sequence and a higher-ordered structure. In this system FRET was maximal when probes were free in solution and a decrease in FRET was evidence of successful hybridization. We used a single-stranded oligodeoxyribonucleotide labeled at its 5'-end and its 3'-end with 6-carboxyfluorescein and 6-carboxytetramethylrhodamine, respectively. Incubation of the probe with a single-stranded complementary oligonucleotide reduced the FRET. Moreover, a small change in FRET was also observed when the probe was incubated with an oligonucleotide in which the target site had been embedded in a stable hairpin structure. The decrease in the extent of FRET depended on the length of the stem region of the hairpin structure and also on the higher-ordered structure of the probe. These results indicate that this spectrofluorometric method and FRET probes can be used to estimate the efficacy of hybridization between a probe and its target site within highly ordered structures. This conclusion based on changes in FRET was confirmed by gel-shift assays.

DNA↗
PubMed1998

Dietary supplementation of catechins and alpha-tocopherol accelerates the healing of trinitrobenzene sulfonic acid-induced ulcerative colitis in rats.

The effects of dietary catechins and alpha-tocopherol on inflammatory bowel disease in rats were examined. Male 9-week-old rats were intracolonically administrated trinitrobenzene sulfonic acid (TNBS) and fed the experimental diets containing 0.05% catechin and 0.025% alpha-tocopherol for 1 week, then dissected. The extent of colitis-induced TNBS was assessed macroscopically. The supplementation of catechins and alpha-tocopherol significantly decreased colonic damage compared with the group fed the basal diet (the disease control). In particular, catechin feeding completely inhibited the development of colon adhesions. Colonic myeloperoxidase (MPO) activity, which is a marker of neutrophil infiltration into the colonic mucosa, was lower in the groups that had been given catechins and alpha-tocopherol. The levels of thiobarbituric acid reactive substances in colon was highest in the disease control group; however, the differences among the groups were not significant. Plasma alkaline phosphatase activity was maintained at normal levels in the rats supplemented with catechins and alpha-tocopherol. These results suggest that catechins and alpha-tocopherol have anti-inflammatory effects on TNBS-induced rat colitis.

Alkaline Phosphatase↗
PubMed1997

[The usefulness of 18F-FDG SPECT imaging in evaluating myocardial viability].

UNLABELLED: We compared myocardial viability evaluated by 18F-deoxyglucose (FDG) SPECT in 14 old myocardial infarction patients with that evaluated by 201TI SPECT and 123I-beta-methyl-iodophenyl pentadecanoic acid SPECT as imaging of fatty acid metabolism. FDG-SPECT was performed after oral administration of glucose. From each SPECT image which was divided into 7 segments, the degree of accumulation of each radioisotope (RI) was visually classified into four grades of defect score (ranging from 0 as normal to 3 as severe defect). The % uptake in the same area was also quantitatively calculated. RESULTS: The degree of accumulation of myocardial Rl relative to regional wall motion. FDG is the most wide for a range of accumulation of Rl of infarct area. Also, at FDG, in the area of wall motion had done a disorder, the degree of accumulation was higher than other two methods. In the infarcted area, the degree of accumulation on FDG-SPECT in the area of decreased wall motion was greater than that on the other two procedures. These results suggest that FDG-SPECT is useful for evaluating myocardial viability.

Aged↗
PubMed1997

[Outpatient chemotherapy with continuous intravenous infusion for patients with recurrent renal cell carcinoma or advanced prostate carcinoma].

We tried outpatient chemotherapy with continuous intravenous infusion of 5-fluorouracil (5-FU) and cisplatin (CDDP) for patients with recurrent renal cell carcinoma or advanced prostate carcinoma. This study was designed to evaluate the efficacy of our drug delivery system using two disposable balloon pumps and subcutaneous port, subjective symptoms caused by chemotherapy, and quality of life (QOL). There were 12 patients, including 7 cases of recurrent renal cell carcinoma and 5 cases of advanced prostate carcinoma. Their performance status (PS) was grade 0 or 1. The protocol for renal cell carcinoma consisted of combined chemotherapy with continuous infusion of 5-FU 250 mg/m2/day and CDDP 3 mg/m2/day in 2 weeks for 1 cycles (4 weeks). 5-FU and CDDP were administered with the Baxter infuser pumps (Intermate LV 1.5) and after 1 week we changed the new pumps. In treating advanced prostate carcinoma, Honvan 100 mg/day was substituted for 5-FU. We experienced 2 cases of problems with the drug delivery system during 10 months, which needed a change of the subcutaneous port. QOL score and subjective symptoms showed that patients were not always free because of carrying pumps and the side effects of chemotherapy, but they can return to social life and family instead of spending much time in the hospital. In conclusion, our drug delivery system is safe for outpatient chemotherapy, and QOL of patients with home anti-cancer chemotherapy is higher than that of patients with chemotherapy in the hospital.

Adult↗
PubMed1997

Structural analysis of nucleic acids by using fluorescence resonance energy transfer (FRET).

We examined changes in the extent of fluorescence resonance energy transfer (FRET) between two different fluorochromes attached to a single oligonucleotide in the presence or absence of target nucleic acids with a specific sequence and a higher-ordered structure. In our system, FRET was maximal when probes were free in solution and a decrease in FRET was evidence of successful hybridization. Incubation of the probe with a single-stranded complementary oligonucleotide reduced the FRET. While, a small change in FRET was also observed when the probe was incubated with an oligonucleotide in which the target site had been embedded in a stable hairpin structure. These results indicate that this spectrofluorometric method and FRET probes can be used to estimate the efficacy of hybridization between a probe and its target site within highly ordered structures. It should help us to estimate the suitability of designed functional molecules, such as antisense DNA and RNA and ribozymes, that target to specific sites.

DNA↗
PubMed1994

[Splenic autotransplantation restores the immune function of the spleen].

Splenectomy has been reported to reduce the immune function. Fischer rats were subjected to 1), splenectomy, 2) splenectomy and autotransplantation and 3) sham control, respectively and examined for the production of antibodies against heterogeneic red blood cells, natural killer (NK) activity of peripheral blood lymphocytes (PBL), and the effects against tumor metastasis. Autotransplanted spleen started to produce antibody against the intravenously injected the sheep red blood cells (SRBC) even 2 weeks after autotransplantation and produce high titer of antibody as like sham operated rats 8 weeks after the operation. NK activity was decreased 2 weeks after splenectomy, but not after splenic autotransplantation. Immunohistopathological examination with monoclonal antibody against rat's lymphocytes showed the similar regeneration of B cells and T cells with normal spleen. Fischer rats which had been inoculated with FMC7 (fibrosarcoma) had their tumors resected 12 days after the inoculation and were divided into the 3 groups according to the operative procedures mentioned above and were operated on respectively. Then FMC7 were challenged intravenously or intraperitoneally, and their survival times were examined. No significant difference was found in the groups of intraperitoneal inoculation. But in the case of intravenous challenge, averaged survival time was significantly prolonged in the group of sham operation. These results suggested the spleen worked against intravenous antigens including even tumor cells. Heterotopic splenic autotransplantation is a method to restore some parts of the splenic immune function.

Animals↗
PubMed1993

Protein chemotaxonomy of genus Datura: identical amino acid sequence of ferredoxin from two varieties of Datura stramonium.

The complete amino acid sequence of the respective [2Fe-2S] ferredoxins from two varieties of Datura stramonium, D. stramonium var. stramonium and D. stramonium var. tatula, have been determined by automated Edman degradation of the entire Cm-protein and of the peptides obtained by tryptic digestion and CNBr treatment. The ferredoxins from the two plants exhibited identical amino acid sequences, suggesting a very close taxonomic relationship between the two. This result supports the proposal by Blakeslee and others that these plants, at first named by Linnaeus as two distinct species, i.e. D. stramonium L. and D. tatula L., should be considered two varieties of a single species.

Amino Acid Sequence↗
PubMed1992

Heterotopic brain tissue of the soft palate.

Heterotopic brain tissue is an unusual substance which is very difficult to diagnose correctly preoperatively. We report on a 7-month-old male infant with heterotopic brain tissue of the soft palate, and describe the results of preoperative examinations including brain scintigraphy, angiography, brain computed tomography and magnetic resonance imaging (MRI). MRI was found useful to show that the tumor had no junction with the intracranial space. The patient was treated successfully without complication or recurrence after 1.5 years follow-up.

Brain↗
PubMed1992

Studies on the conformational aspects of inulin oligomers.

The conformational studies of inulin oligomers from G-F2 to G-F9, which isolated from Platycodon grandiflorum, suggested a plausible conformational change between G-F7 and G-F8 from the trends in their chemical shift patterns and molecular rotation; the oligomers higher than G-F8 would form some secondary conformations more rigid than shorter oligomers. On the other hand, spin-lattice relaxation (T1) studies of the protons proposed through-space interactions of 2- and 4-H's of glucose moiety in G-F5, presumably with some atom(s) of the terminal fructose moiety. This would reflect that the inulin molecule adopts a 5/1 helix.

Carbohydrate Conformation↗
PubMed1992

[Prognostic significance of internal mammary lymph node metastases in breast cancer patients].

Examination was made of clinical, histological and biological prognostic factors in 207 patients with invasive breast cancer, and determination was made as to whether variable prognostic factors, especially internal mammary lymph node metastases, would serve as a basis for the prognosis of breast cancer. In a univariate study, overall survival was significantly corrected with tumor size, axillary lymph node status, axillary and internal mammary lymph node metastases and DNA ploidy status. In a multivariate study, however, only axillary and internal mammary lymph node metastases were recognized as important, and independent prognostic factors on survival. Neither axillary lymph node status nor DNA ploidy status appeared an important prognostic factor. Axillary and internal mammary lymph node metastases could not be predicted from their clinical assessment. Only axillary lymph node dissection and biopsy of first and second intercostal spaces were concluded to be useful for accurately indicating the status of these lymph nodes.

Adult↗