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T Noma

Publications and source records attributed to T Noma.

At least 55 records · Page 3Linked to original sources
PubMed1998

Effects of the non-selective 5-HT receptor agonist, 5-carboxamidotryptamine, on plasma glucose levels in rats.

The effects of the 5-HT1A/1B/1D/5/7 receptor agonist, 5-carboxamidotryptamine (5-CT), on blood glucose, insulin and glucagon levels in rats were investigated. 5-CT above the dosage of 0.05 mg/kg elicited significant hyperglycemic effects and 0.1 mg/kg, induced a 35% increase in plasma glucose levels. 5-CT did not affect plasma glucagon, and serum insulin levels increased following the high dose of 5-CT. Adrenodemedullation abolished the 5-CT-induced hyperglycemia. Hyperglycemia induced by 5-CT was prevented by pretreatment with the 5-HT1/2/7 receptor antagonist, metergoline, and the 5-HT1/2/5/7 receptor antagonist, methysergide, although the 5-HT2A receptor antagonist, ketanserin, the 5-HT2A/2B/2C receptor antagonist, ritanserin, and the 5-HT3/4 receptor antagonist, tropisetron, had no effect. Although 5-CT has a high affinity with 5-HT1A receptors, the 5-HT1A and 5-HT1B and beta receptor antagonist, (-)-popranolol, did not affect 5-CT-induced hyperglycemia. These results indicate that 5-CT-induced hyperglycemia is elicited by facilitation of adrenaline release from the adrenal gland and that 5-CT-induced hyperglycemia is mediated by the 5-HT7 receptor unrelated to 5-HT1A, 5-HT1B, 5-HT2, 5-HT3, 5-HT4 or 5-HT5 receptors.

8-Hydroxy-2-(di-n-propylamino)tetralin↗
PubMed1998

Molecular cloning and characterization of the gene encoding human NeuroD.

NeuroD is a basic helix-loop-helix transcription factor that binds to an E-box sequence, CANNTG, in the target gene promoter region. The gene encoding NeuroD is expressed specifically in brain, intestine, and pancreatic cells and plays a pivotal role in tissue-specific differentiation. To investigate the regulation of human NeuroD gene expression, we isolated and sequenced a genomic DNA containing two exons and flanking regions of the NeuroD gene. The sizes of exons 1 and 2 were 168 and 2404 bp, respectively. CAT reporter analysis showed that the elements responsible for basal promoter activity lay in the proximal 408-bp region. Cotransfection of the CAT reporter plasmids with a NeuroD expression plasmid resulted in 5-fold enhancement of the CAT activity, indicating an autoregulatory mechanism is involved in human NeuroD gene expression.

Amino Acid Sequence↗
PubMed1998

Micro X-ray diffraction analysis of thin films using grazing-exit conditions.

An X-ray diffraction technique using a hard X-ray microbeam for thin-film analysis has been developed. To optimize the spatial resolution and the surface sensitivity, the X-ray microbeam strikes the sample surface at a large glancing angle while the diffracted X-ray signal is detected with a small (grazing) exit angle. Kirkpatrick-Baez optics developed at the Photon Factory were used, in combination with a multilayer monochromator, for focusing X-rays. The focused beam size was about 10 x 10 micro m. X-ray diffraction patterns of Pd, Pt and their layered structure were measured. Using a small exit angle, the signal-to-background ratio was improved due to a shallow escape depth. Under the grazing-exit condition, the refraction effect of diffracted X-rays was observed, indicating the possibility of surface sensitivity.

Journal Article↗
PubMed1998

Effect of oxatomide on T-cell activation and the production of interferon-gamma in mite sensitive asthma.

Interleukin-2 responsiveness of lymphocytes induced by Dermatophagoides farinae antigen was suppressed upon exposure to 20 to 2000 ng/ml of oxatomide for 24 h in a dose-related manner in children with mite-sensitive bronchial asthma. Suppression was greater in the plastic-adherent antigen-presenting cells than in the T-cells. Oxatomide suppressed the production of interleukin-1alpha induced by Dermatophagoides farinae antigen in plastic-adherent cells. These results indicate that the target cells of oxatomide are antigen-presenting cells and not T-cells. Oxatomide also suppressed interleukin-2 responsiveness in lymphocytes exposed to purified protein derivative, but not in those exposed to concanavalin A. Unlike its effect on cell proliferation, oxatomide potentiated the Dermatophagoides farinae-induced production of interferon-gamma, which was suppressed by stimulation with Dermatophagoides farinae antigen in lymphocytes from the patients. In contrast, production of interferon-gamma induced by concanavalin A was not affected by this drug. These results indicate that oxatomide suppresses interleukin-2 responsiveness of allergen-activated helper T-cells and increases the production of interferon-gamma induced by Dermatophagoides farinae antigen, without causing cell proliferation.

Animals↗
PubMed1998

cDNA cloning and tissue-specific expression of the gene encoding human adenylate kinase isozyme 2.

We isolated two kinds of cDNAs encoding human adenylate kinase (AK) isozyme 2 from a HeLa cell cDNA library using bovine AK2 cDNA as a probe. Nucleotide sequencing revealed that the cDNAs encoded 239- and 232-amino acid proteins with deduced molecular mass of 26.5 (AK2A) and 25.6kDa (AK2B), respectively. Northern blot analysis demonstrated that AK2 mRNA is strongly expressed in liver, heart, skeletal muscle and pancreas, and moderately in kidney, placenta and brain, and weakly in lung. However, Western blot analysis showed that AK2 protein was present in large amounts in liver, heart, kidney, and in a small amount in lung, and undetectable in brain and skeletal muscle. These results suggested the presence of the tissue-specific gene-expression including post-transcriptional regulation in expression of the AK2 gene.

Adenylate Kinase↗
PubMed1998

Effects of anxiolytics, diazepam and tandospirone, on immobilization stress-induced hyperglycemia in mice.

The benzodiazepine anxiolytic diazepam did not affect immobilization-elicited hyperglycemia, although a high dose increased blood glucose levels in normal mice. The serotonergic anxiolytic tandospirone reduced immobilization-induced hyperglycemia dose-dependently. Hyperglycemia elicited by immobilization stress was completely prevented by adrenalectomy but not by pretreatment with the corticosterone synthesis inhibitor dexamethasone. These results suggest that the effects of two anxiolytics, diazepam and tandospirone, on immobilization stress-induced hyperglycemia are quite different, although both drugs reduce anxiety. Furthermore, our results indicate that immobilization stress-elevated hyperglycemia is closely related to adrenaline release from the adrenal gland and that tandospirone may inhibit stress-induced hyperglycemia by modifying this mechanism.

Animals↗
PubMed1998

A comparative investigation of the restorative effects of roxithromycin on neutrophil activities.

The effects of roxithromycin, a macrolide antibiotic, on neutrophil activities were investigated in six seriously handicapped patients with severe mental retardation. Neutrophil activities were evaluated by flow cytometry using a heparinized blood analysis method. All six patients showed decreased levels of neutrophil phagocytosis, intracellular killing, and CD11b expression. Treatment with roxithromycin in vitro selectively restored the decreased phagocytic and bactericidal activities of neutrophils in these patients. There was no significant restorative effect with cefaclor, ofloxacin, or aztreonam. These results suggest the need to consider therapeutic effects of antibiotics on neutrophil functions in patients at increased risk for bacterial infections due to decreased neutrophil activities.

Adolescent↗
PubMed1998

Inhibition of physiologic stress responses by regional nerve block during orthognathic surgery under hypotensive anesthesia.

OBJECTIVE: The purpose of this study was to investigate the inhibitory effects of nerve block on stress responses during orthognathic surgery involving general anesthesia with induced hypotension. STUDY DESIGN: Fourteen patients (ASA-1) undergoing Le Fort 1 osteotomy and sagittal splitting mandibular osteotomy were divided into 2 groups: a block group (with maxillary and mandibular nerve blocks; n = 7) and a non-block group (without nerve blocks; n = 7). Anesthesia was maintained with N2O-O2 and isoflurane (block group, 0.8%; non-block group, 1.2%). Adenosine triphosphate was administered for induced hypotension. Observed variables included hemodynamic parameters and fluctuations and adenosine triphosphate dose. Plasma norepinephrine concentrations and blood gases were observed in the block group. RESULTS: More stable hemodynamics, with a lower adenosine triphosphate dose as well as negligible changes in norepinephrine concentrations and blood gases, were obtained in the block group. CONCLUSIONS: The stress responses were inhibited by nerve blocks combined with low-concentration inhalation anesthesia during adenosine triphosphate-induced hypotension. The adenosine triphosphate requirement was reduced under stable hemodynamics achieved with nerve blocks.

Adenosine Triphosphate↗
PubMed1998

Correlation between antigen-specific IL-2 response test and provocation test for egg allergy in atopic dermatitis.

BACKGROUND: The antigen-specific interleukin-2 response (AIR) test using lymphocytes is effective in searching for the antigen which causes allergic diseases and understanding their disease activity. OBJECTIVE AND METHODS: The correlation between the raw egg oral provocation test and egg white antigen-specific interleukin-2 (IL-2) response test was investigated in 123 children with infantile atopic dermatitis and 13 children with bronchial asthma. RESULTS: Among the 83 who showed positive reactions to provocation, 75 also reacted positively to the AIR test (sensitivity, 90.4%), while among the 53 children who showed negative responses to antigen provocation, 45 produced negative responses to the AIR test (specificity, 84.9%). The specificity of egg white IgE RAST score and skin-prick test are 88.7 and 81.3% which are comparable to that of the AIR test. However, their sensitivity was low (38.6 and 66.7%). In the patterns of symptom developed in the provocation AIR displayed late and delayed type allergic responses in addition to the immediate type which RAST reflected. The RAST-negative group composed of 98 patients included 51 (52.0%) who exhibited positive reactions to the provocation test. Among these 44 responded positively to the AIR test (86.3%). CONCLUSION: The AIR test is effective for screening egg white antigen as part of the tests for antigens responsible for allergic diseases and as a test to ascertain the relevant antigens, and that the conditions that could not be diagnosed by RAST can be detected by the AIR test.

Administration, Oral↗
PubMed1998

Reduced IL-1 production in adolescents with mite antigen asthma in remission.

To determine the immunological mechanisms associated with outgrowing mite antigen-induced bronchial asthma during adolescence, we studied the relationship between clinical status and Dermatophagoides farinae (Df) antigen-induced peripheral cell activation by measuring IL-1alpha and IL-1beta production in patients with bronchial asthma. After antigen-driven restimulation in vitro, there was increased IL-1alpha, IL-1beta production by peripheral blood mononuclear cells (PBMC) from patients with active bronchial asthma, while cellular IL-1alpha, IL-1beta production was reduced in patients with asthma in remission. IL-1alpha and IL-1beta production by PBMC (possibly reflecting airway inflammation) after exposure to Df antigen might be down-regulated in patients outgrowing mite antigen-induced asthma, because lipopolysaccharide-induced IL-1alpha, IL-1beta production (seen in both normal individuals and patients with active asthma) was also reduced when patients were in remission.

Adolescent↗
PubMed1998

Pain following intravenous administration of sedative agents: a comparison of propofol with three benzodiazepines.

The purpose of the present study is to compare the injection pain of propofol with that of benzodiazepines when used for intravenous sedation. In addition, we evaluated the efficacy of coadministering a small dose of 1% lidocaine (20 mg) to reduce the pain accompanying propofol injection. Intravenous propofol, diazepam, midazolam, or flunitrazepam were administered on separate occasions to volunteers and outpatients. The degree of injection pain was evaluated by the Visual Analog Scale (VAS) ruler. The efficacy of premixed lidocaine with propofol was also compared among the patients. The venous pain of propofol was significantly more intense than that of the three other drugs (P < 0.05). The injection pain of diazepam was more intense than that of midazolam (P < 0.05). Many patients reported no pain when propofol was coadministered with lidocaine. The addition of a small dose (20 mg) of lidocaine reduced the VAS pain score to comparable levels observed for benzodiazepines. Because injection pain might affect the patients' comfort during sedation, the addition of lidocaine to the propofol injection is deemed useful for intravenous sedation.

Adult↗
PubMed1997

Differences in sarcoplasmic reticulum gene expression in myocardium from patients undergoing cardiac surgery. Quantification of steady-state levels of messenger RNA using the reverse transcription-polymerase chain reaction.

Little is known about any alterations in sarcoplasmic reticulum (SR) gene expression associated with cardiac diseases of varying degrees of severity. We assessed, using the reverse transcription-polymerase chain reaction (RT-PCR) technique, SR Ca2+ transport protein gene expression in small tissue samples from failing hearts in patients undergoing cardiac surgery. Total RNA was extracted from 30- to 50-mg samples from the hearts of 13 patients with coronary artery disease, congenital heart disease, or valvular heart disease. We used RT-PCR to synthesize and amplify cDNA encoding cardiac SR Ca(2+)-ATPase, ryanodine receptor (RYR), and glyceraldehyde-3-phosphate dehydrogenase (GAPDH). The amount of each mRNA in the sample was expressed relative to the amount of GAPDH mRNA. The expression level of each mRNA was correlated with the cardiac functional index. The mRNA levels for Ca(2+)-ATPase and RYR varied between heart samples, but showed a positive correlation with left ventricular ejection fraction. Ca(2+)-ATPase mRNA levels showed in inverse relationship with plasma brain natriuretic peptide. In addition, we isolated partial cDNA encoding a human cardiac RYR. The cDNA consisted of 487 nucleotides, and the nucleotide and deduced amino acid sequences showed 93% and 99% homology, respectively, to those of rabbit cardiac RYR. These results suggest that decreased levels of mRNA for SR Ca2+ transport protein could be related to abnormal cardiac function, regardless of the etiology of the heart disease. RT-PCR provides a rapid and economical way of quantifying the expression of multiple genes in small specimens and may, therefore, aid understanding of the pathophysiology and treatment of heart disease.

Adolescent↗
PubMed1997

Wild-type p53 gene-induced morphological changes and growth suppression in hepatoma cells.

The human hepatocellular carcinoma (HCC) cell line, HLF, expresses only mutant-type p53 (mt-p53), which has an amino acid substitution at the 244th residue from glycine to alanine. HLF cells were transfected with wild-type p53 (wt-p53) cDNA construct pC53-SN3, mt-p53 cDNA construct pC53-SCX [which differs by a single nucleotide, resulting in alanine instead of valine at the 143rd residue in p53 (p53-143)], or pCMV-Neo-Bam, as a control, by a liposome method. After G418 selection, three wt-p53 stable transformants (WT), four mt-p53 transformants (MT), and three control vector transformants (VT) were obtained. We analyzed the cell growth and morphological changes of these transformants under different culture conditions [fetal calf serum (FCS), 10%, 1%, and 0%]. Whereas no difference from control in the growth rate and morphology was observed under the 10% FCS conditions, serum starvation induced remarkable phenotypical changes in all three WTs, but not in the other transformant. Corresponding to these phenotypical changes, the transcriptional activity of wt-p53 was increased more than nine fold. These results indicated that serum starvation would induce wt-p53 biological function, which is tightly linked to morphological changes and growth suppression. To induce these changes, the introduction of the wt-p53 gene itself was not sufficient, and additional triggering, i.e., serum starvation, was indispensable.

Carcinoma, Hepatocellular↗
PubMed1997

[Immunomodulation by TYB-2285 of Dermatophagoides farinae (Df) antigen-induced IFN-gamma and IL-4 production in lymphocytes from children with bronchial asthma].

Effect of TYB-2285 and its metabolites on immune responses by peripheral blood mononuclear cells (PBMC) from children with bronchial asthma was investigated. TYB-2285 and its metabolites have immunosuppressive activity for the proliferation by Df-stimulated patients' lymphocytes. Concanavalin A (Con A)-activated peripheral blood mononuclear cells (PBMC) from the patients were not affected by the same treatment. The results indicate that TYB-2285 and its metabolites are capable of suppressing antigen-induced 3H-thymidine (3H-TdR) uptake but not the response induced by Con A. Interferon-gamma (IFN-gamma) production by Df-stimulated PBMC from patients with active asthma, which was lower than that of normal lymphocytes, were reversed beyond the levels of that in normal subjects. Thus reduced production of IFN-gamma by Df-stimulated patients' lymphocytes was increased by TYB-2285 and its metabolites in a dose-dependent manner. This phenomenon was not observed in lymphocytes from normal subjects. Furthermore, TYB-2285 inhibited IL-4 production induced by Df antigen in asthmatic patients' lymphocytes. Taken, together, TYB-2285 could work as a weak immunosuppressant to modify lymphocytes' responses to allergen in patients with bronchial asthma. These data underscore the potential benefit for the patients with bronchial asthma.

Adolescent↗
PubMed1996

Effects of peripheral 5-HT2 and 5-HT3 receptor agonists on food intake in food-deprived and 2-deoxy-D-glucose-treated rats.

Peripherally administered, the 5-HT2 receptor agonist, alpha-methyl-5-hydroxytryptamine (alpha-methyl-5-HT), significantly suppressed the food intake of food-deprived rats. alpha-Methyl-5-HT also inhibited 2-deoxy-D-glucose-induced hyperphagia in rats. The alpha-methyl-5-HT-induced hypophagia was antagonized by the 5-HT2A receptor antagonist, ketanserin. The alpha-methyl-5-HT-induced decrease in food intake of food-deprived rats was not inhibited by prior adrenodemedullation. The peripheral 5-HT3 receptor agonist, 2-methyl-5-HT, did not affect food intake in food-deprived or 2-deoxy-D-glucose-treated rats. These results suggest that the peripheral 5-HT2A receptor may participate in the regulation of food intake and that its hypophagic effects are not associated with its adrenaline-releasing effects from the adrenal gland. Lastly, the peripheral 5-HT3 receptor did not participate in feeding control.

Adrenal Medulla↗
PubMed1996

Cloning of a cDNA encoding the human transforming growth factor-beta type II receptor: heterogeneity of the mRNA.

We have isolated two novel cDNAs encoding the transforming growth factor-beta (TGF-beta) type II receptor (TGF-beta IIR), termed TGF-beta IIR alpha and TGF-beta IIR beta 1 from a human fetal liver library. They have unique nucleotide (nt) sequences, compared with the reported TGF-beta IIR sequence, at the 5' end. Southern blot analysis using probes from each clone detected the specific genomic DNA fragments. RT-PCR analysis revealed a distinct pattern of expression for each isoform. These results indicated that TGF-beta IIR has heterogeneity in the structure, and the expression of TGF-beta IIR isoforms is differentially regulated. The heterogeneity of TGF-beta IIR molecules could be derived from alternative splicing and might elicit specific TGF-beta receptor functions.

Amino Acid Sequence↗