Biomedical subjects

S Harada

Publications and source records attributed to S Harada.

At least 127 records · Page 7Linked to original sources

PubMed2000

[A study of food-dependent exercise-induced anaphylaxis by analyzing the Japanese cases reported in the literature].

We surveyed and analyzed cases of food-dependent exercise-induced anaphylaxis (FDEIA) in the Japanese literature. We found 167 cases which were reported as FDEIA since 1983. Analyzing these case, following characteristic features were revealed: 1) Recent upward trend in the number of reports of FDEIA was noted. 2) Male cases were more frequent than female cases, while about half of the cases were teenager. 3) More than half of the cases were proved to be induced by wheat followed by shrimp. In those under 20, shrimp was the most popular cause rather than wheat. 4) Skin test and/or IgE RAST showed positive results in most cases, suggesting that the response itself is linked to type I allergic reaction. 5) About 40% of the patients had history of atopic disease, indicating that atopic condition may play some role in FDEIA. 6) All cases who performed provocation test with aspirin responded to food challenge and/or exercise in combination with aspirin. This indicates that aspirin plays a key provoking factor in FDEIA. 7) In 17 cases FDEIA attacks were observed during noon recess or physical education class after lunch at school. We stress here the importance of a nation-wide education to school teachers the potential danger of this disorder.

Adolescent↗

PubMed1999

Novel polymorphism in the promoter and coding regions of the human cholecystokinin B receptor gene: an association analysis with schizophrenia.

Genetic variations in the 5'-untranslated region and the coding region of the CCK-B receptor (CCK-BR) gene were investigated in healthy controls. Novel variants (-215 C-->A, Leu37Phe, Arg319Glu) were found in addition to the mutations (Val125Iso, His207His, Arg215His, 2491 C-->A) reported previously. In the present study, association analysis was carried out for these variants between 80 unrelated schizophrenic patients and 100 healthy controls. The genotype frequency of the -215 C-->A nucleotide substitution in the 5'-untranslated region of CCK-BR gene was significantly higher in the schizophrenic patients than in the controls (6.25%, P = 0.037). However, the difference was not significant after Bonferroni correction for multiple comparisons. Moreover, no association was found between the clinical characteristics of the patients and the genotype frequencies of the variants. These results suggest that the CCK-BR gene polymorphisms have no association with schizophrenia nor its clinical heterogeneity. Am. J. Med. Genet. (Neuropsychiatr. Genet.) 88:700-704, 1999.

5' Untranslated Regions↗

PubMed1999

Angiotensin II inhibits insulin-induced egr-1 expression in mesangial cells.

The gene early growth response gene-1 (egr-1) encodes a zinc transcription factor involved in cell proliferation. Increased expression of egr-1 has been linked to heart and kidney disease. In mouse mesangial cells, insulin stimulated egr-1 expression more than angiotensin II, suggesting that insulin may play an important role in stimulating cell proliferation, leading to glomerulonephritis and diabetic nephropathy. Angiotensin II inhibited insulin-induced egr-1 expression but not c-fos expression, and the decrease in egr-1 expression was concurrent with a decrease in insulin receptor substrate-1 (IRS-1) tyrosine phosphorylation. These results suggest that insulin-induced egr-1 expression in mouse mesangial cells is downstream of tyrosine phosphorylation of IRS-1 and activation of the MAP kinase pathway and that crosstalk between angiotensin II and insulin signaling pathways led to an inhibition of IRS-1 tyrosine phosphorylation and egr-1 expression.

Angiotensin II↗

PubMed1999

Antisense display--a method for functional gene screening: evaluation in a cell-free system and isolation of angiogenesis-related genes.

Presented here is an antisense-oriented method for functional gene screening, which we propose naming 'antisense display'. In principle, it consists of four steps: (i) preparation of phosphorothioate antisense repertoires that would correspond to the Kozak's consensus sequence, (ii) subgroup screening to identify active antisense molecules that could cause changes in the cellular phenotypes concerned and (iii) RT-PCR cloning of cDNA with the 5[prime] sense complement and 3[prime] anchor primers and sequence determination, followed by (iv) functional assays of candidate genes. Cell-free translation in rabbit reticulocyte lysate revealed that 10mer or longer antisense effectively halted protein synthesis. This required the presence of RNase H, and was achieved without prior heat-denaturation of the RNA templates. Then, subpools of the 10mer repertoire were administered to human microvascular endothelial cells in culture, and screened for anti-angiogenic activities. A single species having the sequence 5[prime]-GGCTCATGGT-3[prime] consistently inhibited the endothelial cell growth under hypoxia. Through RT-PCR with the corresponding sense primer, we came across three candidate cDNAs. Experiments employing longer unique antisense reproduced marked growth inhibitions in two of the three cDNAs. One encoded a mitochondrial protein and the other, which encoded a putative type-2 membrane protein containing Rab-GAP/TBC and EF-hand like domains, was a gene previously undescribed in human. The results suggest that the antisense display method is potentially useful for isolating new genes towards elucidating their functions.

Amino Acid Sequence↗

PubMed1999

Regulation of the UNC-18-Caenorhabditis elegans syntaxin complex by UNC-13.

The Caenorhabditis elegans unc-13, unc-18, and unc-64 genes are required for normal synaptic transmission. The UNC-18 protein binds to the unc-64 gene product C. elegans syntaxin (Ce syntaxin). However, it is not clear how this protein complex is regulated. We show that UNC-13 transiently interacts with the UNC-18-Ce syntaxin complex, resulting in rapid displacement of UNC-18 from the complex. Genetic and biochemical evidence is presented that UNC-13 contributes to the modulation of the interaction between UNC-18 and Ce syntaxin.

Alleles↗

PubMed1999

Urocortin mRNA is expressed in the enteric nervous system of the rat.

The expression of the urocortin gene in the gastrointestinal tract was investigated using reverse transcription polymerase chain reaction (RT-PCR) and in situ hybridization histochemistry. PCR demonstrated the presence of urocortin mRNA in the rat brain, duodenum, small intestine, and colon. By in situ hybridization, urocortin-containing cells were exclusively localized to the submucosal plexus and myenteric plexus in the duodenum, small intestine and colon. These results suggest that urocortin may play an important role in the regulation of gastrointestinal motor function throughout the enteric nervous system.

Animals↗

PubMed1999

Distinct distribution and time-course changes in neuronal nitric oxide synthase and inducible NOS in the paraventricular nucleus following lipopolysaccharide injection.

Nitric oxide (NO) is known to be involved in the modulation of neuroendocrine function. To clarify the role of different isoforms of NO synthase (NOS) in the neuroendocrine response to immune challenge, the expressions of neuronal NOS (nNOS) and inducible NOS (iNOS) genes in the hypothalamus following lipopolysaccharide (LPS) injection were examined using in situ hybridization. NOS activity was also determined by NADPH-diaphorase (NADPH-d) histochemistry. LPS (25 mg/kg) or sterile saline was injected intraperitoneally to male Wistar rats and the rats sacrificed 30 min, or 1, 2, 3, 5, 12 or 24 h after injection. nNOS mRNA expression in the paraventricular nucleus (PVN) was significantly increased 2 h after LPS injection. iNOS mRNA, which was not detected until 2 h after LPS injection, was significantly increased in the PVN 3 h after LPS injection. Both RNA expressions had returned to basal levels by 12 h after LPS injection. The number of NADPH-d positive cells was significantly increased 5 h after LPS injection. iNOS expression was more robust in parvocellular PVN, while nNOS was distributed mainly in the magnocellular PVN. Double in situ hybridization histochemistry revealed that some of the iNOS- (48.4%) or nNOS-positive cells (34. 3%) in the parvocellular PVN expressed CRF mRNA. The results demonstrate that LPS-induced sepsis causes significant increases in nNOS and iNOS gene expression with different time-courses and distributions, and that iNOS mRNA was more frequently co-localized with CRF-producing parvocellular neurons in the PVN. Thus, NO produced by iNOS and nNOS may play an important role in the neuroendocrine response to an immune challenge. Distinct differences in the distribution and time-course changes of iNOS and nNOS suggest different roles for the hypothalamic-pituitary-adrenal axis and/or neurohypophyseal system.

Animals↗

PubMed1999

Association of protein-tyrosine phosphatase PTP-BAS with the transcription-factor-inhibitory protein IkappaBalpha through interaction between the PDZ1 domain and ankyrin repeats.

PTP-BAS is a membrane-associated protein tyrosine phosphatase containing a band-4.1 homology region and five PDZ (PSD-95 Dlg ZO-1) [discs-large homology region ('DHR')/Gly-Leu-Gly-Phe ('GLGF')] domains. The second and fourth PDZ domains were reported to associate with Fas/CD95. By using the first PDZ domain as a bait in yeast two-hybrid screening, we have identified IkappaBalpha as a binding protein. IkappaBalpha associated with PDZ1 through the stretch of the N-terminal three ankyrin repeats. The association was also confirmed in HeLa cells by co-immunoprecipitation experiments. Inhibition of PTP-BAS by expression of dominant-negative PTP-BAS mutant resulted in tyrosine-phosphorylation of IkappaBalpha. Tyrosine-phosphorylation of IkappaBalpha is a key event in activation of nuclear factor (NF)-kappaB during reoxygenation. PTP-BAS may thus play a regulatory role in activation of NF-kappaB under high oxidative stress.

Ankyrins↗

PubMed1999

Production of interleukin-7 and interleukin-15 by fibroblast-like synoviocytes from patients with rheumatoid arthritis.

OBJECTIVE: To examine the ability of fibroblast-like synoviocytes in rheumatoid arthritis (RA) to produce interleukin-7 (IL-7) and IL-15, and the ability of these cytokines to induce the proliferation of synovium-infiltrating T cells. METHODS: Messenger RNA (mRNA) and protein levels of IL-7 and IL-15 in synovial tissue cells and fibroblast cell lines were determined by reverse transcriptase-polymerase chain reaction and enzyme-linked immunosorbent assay, respectively. T cell-enriched populations from RA synovial tissues were isolated by deleting adherent cells after a 14-hour incubation in plastic dishes or by expanding T cells during a 14-day incubation of tissue cells with IL-2 alone, and their proliferative responses to IL-7, IL-15, and IL-2 were measured by 3H-thymidine incorporation. RESULTS: Freshly isolated cells from RA synovial tissues more strongly expressed mRNA for both IL-7 and IL-15 compared with the cells from osteoarthritis tissues, and could spontaneously release greater amounts of these cytokine proteins in culture. Fibroblast cell lines prepared from RA patients were able to produce large amounts of IL-15 and small amounts of IL-7 at both the transcriptional and protein levels, and their cytokine production was significantly elevated when stimulated with IL-1 and tumor necrosis factor alpha. Purified synovial tissue macrophages spontaneously released IL-15 but not IL-7, and synovial T cells did not produce either cytokine. IL-7 and IL-15, similar to IL-2, stimulated the proliferation of synovial tissue T cells from RA patients; IL-7 was less potent than IL-15 or IL-2. CONCLUSION: These results indicated that fibroblast-like synoviocytes are an important source of the cytokines with IL-2-like activity, IL-15 and IL-7, in RA joints, and that IL-15 may be mainly responsible for local T cell activation and expansion in the presence of deficient IL-2 production by T cells.

Arthritis, Rheumatoid↗

PubMed1999

Mechanisms of nuclear translocation of insulin.

Insulin (Ins) and various other hormones and growth factors have been shown to be rapidly internalized and translocated to the cell nucleus. This review summarizes the mechanisms that are involved in the translocation of Ins to the nucleus, and discusses its possible role in Ins action, based on observations by the authors and others. Ins is internalized to endosomes by both receptor-mediated and fluid-phase endocytosis, the latter occurring only at high Ins concentrations. The authors recently demonstrated the caveolae are the primary cell membrane locations responsible for initiating the signal transduction cascade induced by Ins. Once Ins is internalized, Ins dissociates from the Ins receptor in the endosome, and is translocated to the cytoplasm, where most Ins is degraded by Ins-degrading enzyme (IDE), although how the polypeptides cross the lipid bilayer is unknown. Some Ins escapes the degradation and binds to cytosolic Ins-binding proteins (CIBPs), in addition to IDE. IDE and some CIBPs are known to be binding proteins for other hormones or their receptors, and are involved in gene regulation, suggesting physiological relevance of CIBPs in the signaling of Ins and other hormones. Ins is eventually translocated through the nuclear pore to the nucleus, where Ins tightly associates with nuclear matrix. The role of Ins internalization and translocation to the nucleus is still controversial, although there is substantial evidence to support its role in cellular responses caused by Ins. Many studies indicate that nuclear translocation of various growth factors and hormones plays an important role in cell proliferation or DNA synthesis. It would be reasonable to suggest that Ins internalization, its association with CIBPs, and its translocation to the nucleus may be essential for the regulation of nuclear events by Ins.

Animals↗

PubMed1999

Novel variants in the promoter region of the CREB gene in schizophrenic patients.

Cyclic AMP-responsive element-binding protein (CREB) is one of the messenger molecules involved in intracellular signal transduction pathways used by most dopamine and serotonin receptor subtypes. In addition, CREB stimulates the expression of a number of genes, alterations in the expression of which may be associated with schizophrenia. The promoter region of the human CREB gene was therefore analyzed to identify genetic variants that may lead to the modification of CREB expression and contribute to schizophrenia. Eighty unrelated schizophrenics and 100 healthy controls were screened for genetic variants of the CREB gene by SSCP analysis, followed by direct sequencing of PCR products. Two novel variants (-933T-->C and -413G-->A) were found only in schizophrenics. A patient with the -933T-->C variant had unusual clinical characteristics in addition to typical schizophrenic symptoms.

Cyclic AMP Response Element-Binding Protein↗

PubMed1999

Effect of stress on atopic dermatitis: investigation in patients after the great hanshin earthquake.

BACKGROUND: Although a variety of factors are responsible for atopic dermatitis (AD), very little is known about the effect of stress caused by a natural disaster on AD symptoms. OBJECTIVE: This study was conducted to assess the effect of stress or trauma on the symptoms of AD. METHODS: One thousand four hundred fifty-seven patients with AD (745 males and 712 females), diagnosed by using the criteria of the Japanese Dermatology Association, were enrolled in the study. The data were obtained from a self-administered questionnaire given to patients with AD after experiencing the Great Hanshin Earthquake. The data were analyzed by multivariate logistic regression analysis. Patients were divided into 3 groups: area A, severe damage to buildings and houses; area B, mild damage; and control area, no damage. RESULTS: Exacerbation of skin symptoms was found in 38% and 34% of patients in areas A and B, respectively, whereas similar exacerbation was seen in 7% of control patients. Nine percent and 5% of the patients in areas A and B, respectively, showed improvement in their symptoms compared with 1% in the control group. The earthquake caused stress in 63% and 48% of the patients in areas A and B, respectively, but fewer patients felt stress in undamaged areas (19%). Multiple logistic regression analysis revealed that of the factors examined here, subjective distress is the factor that is most responsible for the exacerbation of skin symptoms (odds ratio, 2.98; 95% confidence interval, 2.25-3.96). CONCLUSION: The results presented here strongly suggest that stress caused by a natural disaster influences AD symptoms.

Adolescent↗

PubMed1999

Association between polymorphism of the cholecystokinin gene and idiopathic Parkinson's disease.

Parkinson's disease (PD) is characterized by major alterations of neurotransmitter activity due to damage of the substantia nigra. Changes in neuropeptide concentration within the basal ganglia may play an important role in the putative dopaminergic-peptidergic interactions associated with the disease. Cholecystokinin (CCK) modulates the release of dopamine in the mesolimbic pathway and affects dopamine-related behavior. We analyzed genetic variations in the CCK gene, in both the coding and promoter region, in order to investigate the role of polymorphism in idiopathic PD. Four polymorphic sites of the CCK gene (-196G/A, -45C/T, 1270C/G, 6662C/T) were found in PD patients and controls. Complete linkage disequilibrium was observed between the -45 locus and the 1270 locus, and also a possible linkage disequilibrium was found between the -45 and -196 loci. A significant difference was found in the distributions of three identified genotypes at the -45 locus between 116 PD patients and 95 age-matched control subjects (chi2 = 7.95, p = 0.018, Bonferroni correction; p = 0.054). In addition, a significant difference was obtained amongst the three genotypic groups at the -45 locus when compared between PD patients who experienced hallucinations (n = 23) and those (n = 93) who did not (chi2 = 8.08, p = 0.018, Bonferroni correction, p = 0.126). Our data suggested that mutations at the -45 locus in the promoter region of the CCK gene may influence vulnerability to hallucinations in PD patients treated with L-dopa.

Age of Onset↗

PubMed1999

Bone mineral density in steroid-dependent asthma assessed by peripheral quantitative computed tomography.

Chronic use of systemic glucocorticoids results in progressive bone loss and pathologic fractures. This study identified the predictive variables for bone loss and used peripheral quantitative computed tomography (pQCT) to measure changes in cortical and trabecular bone in patients receiving systemic glucocorticoid therapy of prednisone 15.4 g. Eighty-four asthmatic patients were included in the study. Vertebral fractures were diagnosed via plain spinal radiograms. pQCT was used to measure cortical and trabecular bone mineral density. Multiple regression analysis identified variables with predictive value. The cumulative dose of glucocorticoid correlated with the bone mineral density (p<0.05) and the trabecular bone density (p<0.01). Among patients > or = 65 yrs of age, the cumulative dose of glucocorticoid correlated with the occurrence of vertebral fractures (p<0.05), total bone mineral density (p<0.01) and cortical bone mineral density (p<0.01). Bone mineral density in the distal radius measured by pQCT and the vertebral bodies by axis QCT were correlated, regardless of whether systemic glucocorticoids were administered. Glucocorticoid administration not only decreases trabecular but also cortical bone mineral density. Since cortical bone provides strength and stiffness, it appears that the loss of cortical bone is responsible for the increased incidence of fracture seen in patients receiving systemic glucocorticoid therapy.

Aged↗

PubMed1999

Molecular and immunological dissection of diffuse large B cell lymphoma: CD5+, and CD5- with CD10+ groups may constitute clinically relevant subtypes.

Diffuse large B cell lymphoma (DLBL) constitutes the greatest percentage of adult non-Hodgkin's lymphomas and represents a diverse spectrum of lymphoid neoplasms. Clinicopathologic, phenotypic and genotypic findings were correlated and compared for 63 DLBL cases to investigate whether they represent clinically relevant subtypes. They were all cyclin D1 negative and were phenotypically divided into three groups, ie group I (CD5+ type, n=11), group II (CD5- CD10+ type, n=19), and group III (CD5- CD10- type, n=33). Data were correlated by observing the respective gene rearrangement and expression of BCL2 and BCL6. In clinical aspects, the group I cases demonstrated a significantly inferior survival than those of the other two groups (log-rank test, P = 0.016). Although rearrangement of BCL2 and BCL6 did not show any inclination to a specific subgroup, the immunohistochemical detection of BCL2 was less frequent, at a statistically significant level (P=0.011), in group II (50%) than in group I (82%) and III (82%) cases. This appears to confirm the unique aspect of the CD5- CD10+ type DLBL, indicating a certain relationship with the normal germinal center cells which usually lack BCL2 expression. The BCL6 protein expression was detected in most of the present DLBL cases (92%) irrespective of this grouping. These data suggest that the phenotypic delineation by the detection of CD5 and CD10 will improve our understanding of DLBL and be helpful in a future subgrouping of DLBL.

Adult↗

PubMed1999

A clinical study on the effects of pulsed Nd:YAG laser irradiation at root canals immediately after pulpectomy and shaping.

OBJECTIVE: The effects of pulsed Nd:YAG laser irradiation for the treatment of root canals immediately after pulpectomy and shaping with regard to improvement of symptoms were evaluated clinically. SUMMARY BACKGROUND DATA: The effects of pulsed Nd:YAG laser irradiation for the treatment of root canals were experimentally investigated using an animal model, but not under clinical conditions. MATERIALS AND METHODS: Thirty-eight teeth from 29 patients were diagnosed as normal or irreversible pulpitis were used. After extirpation of pulp and shaping using a step-back technique and cleansing with 5% sodium hypochlorite (NaOCl) and 3% hydrogen peroxide (H2O2), laser irradiation was applied at 1 W and 15 pps for 1 second in 23 teeth (laser-treated group). Root canals were then obturated with gutta-percha points and sealer by the lateral condensation method. The condition of the obturations was confirmed radiographically. The control teeth were treated in the same way, but without laser irradiation. Occurrence of spontaneous pain was recorded 1 day after treatment and occurrence of percussion pain was recorded 1, 2, and 3 weeks after treatment. RESULTS: Effective ratio, which was the ratio of the number of "none" teeth to total teeth number in the laser-treated group, was higher than that in the control group, but there was no significant difference between 2 groups with regard to spontaneous and percussion pain (p > 0.05). CONCLUSION: These results suggest that the clinical application of pulsed Nd:YAG laser might be advantageous for the one-visit treatment of root canals immediately after pulpectomy shaping and to reduce postoperative pain.

Adolescent↗

PubMed1999

Chemically induced infection of CD4-negative HeLa cells with HIV-1.

Infection with human immunodeficiency virus type-1 (HIV-1) requires the presence of a CD4 molecule and chemokine receptors such as CXCR4 or CCR5 on the surface of target cells. However, it is still not clear how the virus enters the cells. Although CD4 was initially identified as the primary receptor for HIV-1, the expression of CD4 or one of the chemokine receptors alone is not sufficient to render susceptibility to infection with the virus. To ascertain whether or not adsorption of the virus needs charge-to-charge interaction between viral envelope and host cell membrane protein(s) and if binding alone promotes penetration of the virus into the cells, we have developed a chemically induced infection system targeting a CD4-negative and CXCR4-positive HeLa cell clone (N7 HeLa) which is usually not susceptible to infection with the LAI strain of HIV-1. Use of a poly-L-lysine (PLL)-coated culture plate to enhance the attachment of the virus to the cells made N7 HeLa cells infectable with HIV-1 at very low efficiency. PLL alone cannot fully substitute for the function of the CD4 molecule. However, trypsin-treated viruses, which have largely lost infectivity to CD4-positive MT-4 cells that are highly susceptible to HIV-1 infection, enhanced infectivity against N7 HeLa cells when the PLL-coated plate was used. These results provide evidence that infection with HIV-1 requires both high binding affinity between viruses and cells, and then needs a modification of the viral envelope such as cleavage of gp120/160 to enhance the infection, probably resulting in exposure of the hydrophobic fusion domain of gp41. HIV-1 infection of N7 HeLa cells was also enhanced by treatment with low pH, 12-O-tetradecanoylphorbol-13-acetate (TPA) and some factor(s) from the MT-4 cell culture supernatant. Not only tight viral adsorption with cleavage of the viral envelope but also some activated status of the cells may be required for sufficient HIV-1 infection in this artificial condition.

Amino Acid Sequence↗

PubMed1999

Genetic association between alcohol withdrawal symptoms and polymorphism of CCK gene promoter.

In the central nervous system, cholecystokinin (CCK) is an important neurotransmitter that gives the influences on firings, anxiety, notiception, and dopamine-related behavior. CCK co-exists in the dopaminergic neurons, interacting with dopamine. In this study, we examined the genetic variant -45 C to T substitution of the CCK gene promoter region among 195 healthy Japanese and 174 patients with alcohol withdrawal syndrome (52 delirium tremens, 39 hallucinosis, 20 seizures, and 92 lack of these symptoms) by using polymerase chain reaction-based single-strand conformational polymorphism analysis. Patients with delirium tremens showed a significantly higher frequency of the variant, compared with the controls (chi2 = 4.91, p < 0.03), but patients with other symptoms showed no difference. These data suggested that the individuals possessing allelic mutation (-45T) in the promoter region of the CCK gene might be susceptible to delirium tremens caused by alcohol abuse.

Cholecystokinin↗