Biomedical subjects

S Harada

Publications and source records attributed to S Harada.

At least 55 records · Page 3Linked to original sources

PubMed2001

Differential in vitro effects of IL-4, IL-10, and IL-13 on proinflammatory cytokine production and fibroblast proliferation in rheumatoid synovium.

The purpose of this study was to compare the potential of interleukin-4 (IL-4), IL-10, and IL-13 to interrupt two major inflammatory pathways in rheumatoid arthritis (RA), i.e., overexpression of proinflammatory cytokines and cytokine-mediated fibroblast growth. IL-4, IL-10, and IL-13 were all able to significantly inhibit the production of IL-1beta, tumor necrosis factor-alpha (TNF-alpha), IL-6, and IL-8 by freshly isolated RA synovial tissue cells, IL-10 was most effective in terms of IL-1beta and TNF-alpha reduction. The IL-1 receptor antagonist was enhanced by IL-4 and IL-13, but only slightly enhanced by IL-10. Spontaneous interferon-gamma secretion was diminished by IL-4 and IL-10 but not by IL-13. Addition of anti-IL-10 neutralizing antibody to RA synovial tissue cells resulted in a substantial increase in IL-1beta and TNF-alpha levels, whereas neither anti-IL-4 nor anti-IL-13 antibody had a significant effect. IL-1beta-stimulated proliferation of RA synovial fibroblast cell lines was inhibited by IL-4 and IL-13, but not by IL-10; IL-4 was over tenfold more effective than IL-13. These results suggest that IL-4, IL-10, and IL-13 all have the therapeutic potential to regulate the disease activity mediated by proinflammatory cytokines in RA, but each cytokine may have different potencies.

Arthritis, Rheumatoid↗

PubMed2001

Association analysis of polymorphisms in the prepronociceptin gene and schizophrenia.

The human prepronociceptin (ppNoc) gene is located on chromosome 8p21, and several linkage studies have suggested that the susceptibility locus for schizophrenia is present in this chromosomal region. We investigated genetic variations in the promoter and coding regions of the ppNoc gene to determine if there may be an association between naturally occurring mutations and the manifestation of schizophrenia. Association analyses for the variations found were conducted between 87 unrelated schizophrenic patients and 100 healthy controls. Polymorphisms were found at both the -503 locus (G/A) in the promoter region and the 353 locus (Ala118Gly) in exon 3. Additionally, rare variants were identified at the -261 locus (A/G) in the promoter region, the 515 locus (Gln172Arg) in exon 3, and the 561 locus (G/A) in the untranslated region of exon 3. A significant difference was observed in allele frequency at the 353 locus between controls and patients with continuous-course schizophrenia (P = 0.0237), and between patients with and without prominent negative symptoms (P = 0.0201). However, neither difference was significant after Bonferroni correction. In addition, there were no significant differences in genotype and allele frequencies at either the -503 or 353 locus between the control group and patients with schizophrenia. These results suggest that ppNoc gene polymorphisms have no association with schizophrenia.

Adult↗

PubMed2001

Different expression of androgen receptor coactivators in human prostate.

OBJECTIVES: To investigate the expression of androgen receptor (AR) coactivators in the human prostate for a better understanding of androgen action in prostate cancer. METHODS: Using reverse transcriptase-polymerase chain reaction, we examined the expression levels of AR coactivators (ARA55, SRC1, ARA54, TIF2, RAC3) in four prostate cancer cell lines (DU145, PC3, LNCaP, and LN-TR2), nine benign prostatic tissue samples, and 21 prostate cancer tissue specimens. RESULTS: In the cell lines, SRC1 was expressed ubiquitously at almost equal amounts. Contrary to this, ARA55, ARA54, TIF2, and RAC3 displayed cell line-specific expression. In the LN-TR2 cells, established from LNCaP cells by long-term treatment with tumor necrosis factor-alpha, the expression levels of ARA55 and TIF2 were much higher than those in the LNCaP cells. In every prostatic tissue specimen, the expression levels of TIF2 and RAC3 were very low. The expression levels of ARA55 and SRC1 were higher in the cancer specimens with a higher grade or poor response to endocrine therapy than in those with a lower grade or good response to endocrine therapy. CONCLUSIONS: Prostate cancer cells express AR coactivators. Long-term stimulation by tumor necrosis factor-alpha could increase ARA55 and TIF2 expression in LNCaP cells. The different expression of coactivators may contribute to the different response of prostate cancer to androgenic stimulation or endocrine therapy.

Androgens↗

PubMed2001

Reduction of white coat effect by cilnidipine in essential hypertension.

Stress elevates blood pressure (BP) by increased sympathetic nerve activity. Cilnidipine, a novel dihydropyridine calcium antagonist that has inhibitory actions on N-type as well as L-type voltage-dependent calcium channels, has been reported to attenuate the cold stress-induced increase in plasma norepinephrine and BP in rats. Because white coat effect is associated with an enhanced pressor response to mental stress, we postulated that cilnidipine would attenuate white coat effect in patients with essential hypertension. Sixty-one consecutive outpatients (50 men, 11 women) with essential hypertension were studied prospectively. Twenty-nine patients were treated with either cilnidipine (n = 15) or nifedipine, a representative L-type voltage-dependent calcium antagonist (n = 14). Gender, age, body mass index, duration of hypertension, target organ damage of hypertension, and BP and heart rate (HR) were not significantly different between cilnidipine and nifedipine groups, and both systolic (SBP) and diastolic BP (DBP) were significantly decreased after treatment in both groups. White coat effects on systolic and DBP and HR were not significantly different between groups before antihypertensive treatment. Cilnidipine, but not nifedipine, significantly reduced white coat effects on SBP and HR. Furthermore, white coat effects on systolic BP and HR were significantly lower after treatment in the cilnidipine group compared with the nifedipine group. These data suggest that cilnidipine may reduce white coat effect in hypertensive patients by N-type calcium channel antagonism.

Blood Pressure↗

PubMed2001

Expression of the prostaglandin E(2) (PGE(2)) receptor subtype EP(4) and its regulation by PGE(2) in osteoblastic cell lines and adult rat bone tissue.

Prostaglandins E (especially PGE(2)) stimulate bone formation and increase bone mass in several species including man. The mechanism for this effect, the target cells, and the receptors involved are not known. Specific cell-surface receptors for PGE(2) (EP(1-4)) have been cloned and characterized. EP(4) was reported to be the major receptor in embryonic and neonatal bone tissue in mice, especially in preosteoblasts; however, no data are available regarding its expression in adult bone. This study examines the expression of EP(4) in bone tissue of young adult rats, in which PGE(2) is markedly anabolic, and in various osteoblastic cell lines. Using northern blot analysis, we found that osteoblastic cell lines RCT-1, RCT-3, TRAB-11, and RP-1, primary osteoblastic cells harvested from fetal rat calvaria, as well as tibiae and calvariae of 5-week-old rats express 3.8 kb EP(4) messenger RNA (mRNA). Treatment of periosteal cells (RP-1) in vitro with 10(-6) mol/L PGE(2) increased the levels of both EP(4) mRNA and EP(4) protein, peaking at 1-2 h. Similarly, systemic administration of an anabolic dose of PGE(2) (3-6 mg/kg) to young adult rats upregulated the expression of EP(4) in the tibia and calvaria, also peaking at 1-2 h. Using in situ hybridization, we found increased expression of EP(4) in bone marrow cells of the tibial metaphysis in response to systemic PGE(2) treatment. The preosteoblastic nature of these EP(4)-expressing cells was suggested by the fact that dexamethasone-treated bone marrow stromal cells in culture express EP(4) mRNA, which is upregulated by PGE(2). Northern blot analysis failed to detect both basal and PGE(2)-induced EP(2) mRNA in the bone samples or cell lines tested. Taken together, these data implicate EP(4) as the major cyclic AMP-related PGE(2) receptor subtype expressed in bone tissue and osteoblastic cells and indicate that this receptor is upregulated by its ligand, PGE(2).

Animals↗

PubMed2001

Human T-cell leukemia virus type-I (HTLV-I) tax is not the only one factor to enhance human immunodeficiency virus type-I (HIV-1) infection in culture-supernatants.

It is hypothesized that supernatants from cell cultures contain several factors to modify the human immunodeficiency virus type-1 (HIV-1) infection. Single round infection with pseudotyped viruses with envelope from HIV-1, amphotropic murine leukemia virus (A-MLV) and vesicular stomatitis virus G-protein (VSV-G) carrying luciferase reporter gene detected that not only human T-cell leukemia/lymphoma virus type-I (HTLV-1) transformed cells but also HTLV-I-unrelated T-cells and BJA-B cells released factors enhancing the infection with all pseudotyped viruses in their culture-supernatants. No supernatants upregulated the level of transcription from transfected DNA probe. suggesting that the action of supernatants is different from that of tumor necrosis factor (TNF) and Tax of HTLV-I. These results indicated that factors not always related to HTLV-I were ubiquitously produced and promoted viral infections, probably due to non-specific enhancement of early phase of the infection.

B-Lymphocytes↗

PubMed2001

Aspirin enhances the induction of type I allergic symptoms when combined with food and exercise in patients with food-dependent exercise-induced anaphylaxis.

We examined the effect of aspirin as a substitute for exercise in inducing urticaria/anaphylaxis in three patients with food-dependent exercise-induced anaphylaxis (FDEIA). Two of the patients had specific IgE antibodies to wheat and the other had antibodies to shrimp. Administration of aspirin before ingestion of food allergens induced urticaria in one patient and urticaria and hypotension in another, while aspirin alone or food alone elicited no response. The third patient developed urticaria only when he took all three items, i.e. aspirin, food and additional exercise, whereas provocation with any one or or two of these did not induce any symptoms. These findings suggest that aspirin upregulates type I allergic responses to food in patients with FDEIA, and further shows that aspirin synergizes with exercise to provoke symptoms of FDEIA. This is the first report of a synergistic effect of aspirin in inducing urticaria/anaphylaxis, which was confirmed using challenge tests in patients with FDEIA.

Adolescent↗

PubMed2001

Low-attenuation areas of the lungs on high-resolution computed tomography in asthma.

To investigate the low-attenuation areas of the lungs (LAA) in asthma, we compared the mean lung density (MLD) and the LAA in 22 asthmatics (12 ex-smokers and 10 nonsmokers) and 13 patients with chronic obstructive pulmonary disease (COPD) by high-resolution computed tomography. The MLD and the relative area of the lung with attenuation values lower than -950 Hounsfield Units at full inspiration (inspiratory RA950) were significantly different in nonsmoking asthmatics compared to patients with COPD and asthmatics with a smoking history. The MLD and the RA950 correlated significantly with the FEV1 in all groups and with the DL(CO) in patients with COPD and asthmatics with a smoking history but not in nonsmoking asthmatics. We concluded that the LAA in asthmatics with a smoking history indicates the presence of emphysema, but in nonsmoking asthmatics it reflects hyperinflation and nonemphysematous expiratory airflow limitation rather than emphysematous lesions.

Administration, Inhalation↗

PubMed2001

Grb-2-associated binder-1 is involved in insulin-induced egr-1 gene expression through its phosphatidylinositol 3'-kinase binding site.

The Grb2-associated binder-1 (Gab1) is one of the major adapter molecules downstream of growth factor receptor signaling. Even though insulin causes tyrosine phosphorylation of Gab1, its role in insulin signaling has not been identified yet. We have demonstrated that insulin increased expression of early growth response gene-1 (egr-1), which is one of the most important transcription factors involved in cell proliferation and differentiation. In the present study, the possible role of Gab1 in insulin-induced egr-1 expression was studied using Rat1 fibroblasts expressing human insulin receptors and wildtype Gab1 (HIRc/Gab1(WT)), Gab1 with three tyrosines in the phosphatidylinositol (PI) 3'-kinase binding domain mutated to phenylalanine (HIRc/Gab1(DeltaPI3K)), or histidinol resistance only (HIRc/HIS). Insulin-induced egr-1 expression in HIRc/Gab1(DeltaPI3K) cells was much lower than in the other cells, as determined by Northern blot analysis. These results suggest that Gab1 is involved in the signaling pathway for insulin-induced egr-1 expression through increasing PI3'-kinase activity. The MAP kinase activity increased less with insulin treatment in HIRc/Gab1(DeltaPI3K) cells than in other cells. Inhibition of MAP kinase by the MEK inhibitor completely abolished insulin-induced egr-1 expression. These results suggest that Gab1 increases MAP kinase activity through its PI3'-kinase binding site, which then leads to egr-1 expression. Our results indicate that Gab1 is involved in the control of egr-1 expression regulated by insulin.

Adaptor Proteins, Signal Transducing↗

PubMed2001

Age-related alteration of taste bud distribution in the common marmoset.

Alteration in the number of taste buds on the soft palate (SP), fungiform (FF), foliate (FL) and circumvallate (CV) papillae in the common marmoset at different postnatal ages was examined histologically. After paraffin embedding, complete serial sections at 10 microm thickness were made and stained by HE. Digitized images for each section were examined carefully. The number of FF taste buds at day 1 was 334. While only 20% of all the taste buds at birth possessed a taste pore, 39% of 174 SP taste buds at day 1 possessed a taste pore. The number of taste buds with pores at day 1 was small for the center CV (19 of 59), one side CV (7 of 25), and one side FL (2 of 16). These results suggest that the functional maturation of SP taste buds may precede maturation in other areas of the tongue. The total number of taste buds increased with increasing age, reached a maximum at 2 months of age: FF, 1069; SP, 609; CV-center, 530; CV-side, 390; FL, 201, and decreased thereafter. Almost all taste buds possessed a taste pore after 2 months of age. The decrease in the number of taste buds in the oral cavity with increase in age may change taste sensitivity.

Aging↗

PubMed2001

Metabolic and ethnic determinants of alcohol drinking habits and vulnerability to alcohol-related disorder.

This article represents the proceedings of a symposium at the 2000 ISBRA Meeting in Yokohama, Japan. The chairs were Shoji Harada and Dharam P. Agarwal. The presentations were (1) Mutations in the exons, exon-intron junctions, and promoter regions of human CYP2E1 gene and alcoholism, by Fumio Nomura; (2) Genetic variability in alcohol metabolism and drinking habits in Japanese, by Shoji Harada; (3) Genetic studies of alcohol dependence using alcoholics with inactive ALDH2, by Susumu Higuchi; and (4) Alcohol consumption, apolipoprotein polymorphisms, and cardiovascular disorders, by Dharam P. Agarwal.

Alcohol Drinking↗

PubMed2001

Polymorphism of the 5'-flanking region of the CYP2E1 gene: an association study with alcoholism.

BACKGROUND: Recently, a restriction fragment length polymorphism in the regulatory region of the CYP2E1 gene was identified. It has been suggested that the polymorphism is associated with the elevated activity of the cytochrome P-450 2E1 (CYP2E1) enzyme in obese or alcoholic subjects. However, significance of the polymorphism in connection with alcoholism has not been studied. In the present study, we have characterized these repeated sequences in the 5'-untranslated region of the CYP2E1 gene in Japanese subjects and North American white subjects and investigated whether these polymorphisms are associated with drinking habits and alcoholism. METHODS: DNAs were isolated from blood samples of 192 Japanese nonalcoholics and 202 alcoholics as well as 125 North American white nonalcoholics. DNA samples were amplified by polymerase chain reaction and subjected to a fluorescent-based single-strand conformational change polymorphism analysis, DNA fragment analysis, and polymerase chain reaction-direct sequencing. RESULTS: Four alleles (A1-A4) were found, which were differentiated by the six subunits (L1, L2, L3, L4, S1, S2) based on the size difference and nucleotide replacement. A2 and A4 alleles were observed in the two ethnic groups (A2: Japanese subjects, 0.752; white subjects, 0.976; A4: Japanese subjects, 0.227; white subjects, 0.016). However, A1 allele was found only in North American white subjects (0.008), and A3 allele was detected only in Japanese subjects (0.021). Allele frequencies were significantly different between the two ethnic groups (p < 0.0001). Distribution of genotypes between Japanese nonalcoholics and alcoholics were not significantly different. Also, no significant difference for the allele frequencies was observed between Japanese moderate drinkers and heavy drinkers. CONCLUSIONS: Our data suggested no association among the polymorphic repeats, drinking behavior, and alcoholism. Allele frequencies were significantly different between Japanese subjects and North American white subjects.

5' Untranslated Regions↗

PubMed2001

Polymorphism of the neuropeptide Y gene: an association study with alcohol withdrawal.

BACKGROUND: Neuropeptide Y (NPY) exists in both the central and peripheral nervous system and is thought to modulate many functions such as feeding behavior, anxiety-associated behavior, circadian rhythm, seizure modulation, and hormone secretion. Recent studies have revealed that NPY influences alcohol consumption in mice and that alcohol-preferring rats showed lower concentrations of NPY-like immunoreactivity compared with alcohol-nonpreferring rats in several brain regions. METHODS: In the present study, we analyzed the whole coding region and 5'-untranslating region of the NPY gene for 163 Japanese male alcoholics with different withdrawal symptoms (93 with delirium tremens, 71 with seizures, 49 with hallucinations) and 98 Japanese male controls. ALDH2 genotypes of all subjects tested were ALDH2*1 homozygote. RESULTS: Three polymorphic nucleotide substitutions, namely -121C/A (promoter), 1258G/A (exon 2), and 5671C/T (exon 3), were detected in both groups. Substituting C to A in the -121 locus produced a putative binding site of GATA-1 and GATA-2. Also, -90G/A (promoter) as a rare variant and 5642-5651 single nucleotide repeats T10/T11 (intron 2) were found. Polymorphism (C/T) at the 1128 locus has been reported to be associated with a higher serum cholesterol level in obese white subjects, but such a polymorphism was not found in our samples. The genotypical distributions for these polymorphic loci (-121C/A, 1258G/A, 5642-5651 T10/T11, and 5671C/T) were not significantly different between the alcoholics and controls. However, frequency of the T allele and frequency of the genotype that possessed T alleles (CT, TT) at the 5671 locus were significantly higher in patients with seizure than in those without seizure (p < 0.05, p < 0.02). CONCLUSION: Our data suggested that a C to T substitution at the 5671 locus of the NPY gene may be associated with seizure during alcohol withdrawal.

5' Untranslated Regions↗

PubMed2001

Role of V3 independent domains on a dualtropic human immunodeficiency virus type 1 (HIV-1) envelope gp120 in CCR5 coreceptor utilization and viral infectivity.

The molecular mechanism of human immunodeficiency virus type 1 (HIV-1) entry into cells involves specific interactions between the viral envelope glycoprotein gp120 and two target cell proteins, CD4 and either CCR5 or CXCR4 chemokine receptors. In order to delineate the functional role of HIV-1 gp120 subdomains of dualtropic strains in CCR5 coreceptor usage, we used a panel of chimeric viruses in which the V1/V2 and V3 domains of gp120 from the dualtropic HIV-1(KMT) isolate were introduced either alone or in combination into the T-tropic HIV-1(NL4-3) background. These chimeric constructs were employed in cell-cell fusion and cell-free virus infectivity assays using cell lines expressing CD4 and the CCR5 chemokine receptor. In both assays, the V3 domain of HIV-1(KMT) but not the V1/V2 domain proved to be the principal determinant of CCR5 coreceptor usage. However, in the cell-free viral infectivity assay although a chimeric virus with a combined V1/V2 and V3 domains of HIV-1(KMT) efficiently fused with coreceptor expressing cells, yet its infectivity was markedly diminished in CCR5 as well as CXCR4 expressing cells. Restoring a comparable level of infection of such chimeric virus required the C3-V5 domain from HIV-1(KMT) to be introduced. Our present findings confirmed that the V3 domain is the major determinant of fusion activity and cellular tropism, and demonstrated a dispensable role for the V1/V2 domain. In addition the C3-V5 domain appeared to play an important role in viral infectivity when the corresponding V1/V2 and V3 domains are present.

Amino Acid Sequence↗

PubMed2001

Ectopic expression of MAFB gene in human myeloma cells carrying (14;20)(q32;q11) chromosomal translocations.

Chromosome 14q +, which represents a chromosomal rearrangement involving the immunoglobulin heavy chain gene (IgH) locus, is a genetic hallmark of human multiple myeloma (MM). Here, we report the identification of (14;20)(q32;q11) chromosomal translocations found in MM cells. Double color fluorescence in situ hybridization analyses pinpointed the breakpoints at the 20q11 locus in two MM cell lines within a length of at most 680 kb between the KIAA0823 and MAFB gene loci. Among the transcribed sequences in the vicinity of the breakpoints, an ectopic expression of the MAFB gene, which is located at 450 - 680 kb telomeric to one of the breakpoints and encodes a member of the MAF family basic region / leucine zipper transcription factor, was demonstrated to be associated with t(14;20). This finding, together with that of a previous study describing its transforming activity, suggests that the MAFB gene may be one of the targets deregulated by regulatory elements of the IgH gene as a result of t(14;20).

Avian Proteins↗

PubMed2001

Prostaglandin receptor EP(4) mediates the bone anabolic effects of PGE(2).

Prostaglandin (PG) E(2) is a potent inducer of cortical and trabecular bone formation in humans and animals. Although the bone anabolic action of PGE(2) is well documented, the cellular and molecular mechanisms that mediate this effect remain unclear. This study was undertaken to examine the effect of pharmacological inactivation of the prostanoid receptor EP(4), one of the PGE(2) receptors, on PGE(2)-induced bone formation in vivo. We first determined the ability of EP(4)A, an EP(4)-selective ligand, to act as an antagonist. PGE(2) increases intracellular cAMP and suppresses apoptosis in the RP-1 periosteal cell line. Both effects were reversed by EP(4)A, suggesting that EP(4)A acts as an EP(4) antagonist in the cells at concentrations consistent with its in vitro binding to EP(4). We then examined the effect of EP(4) on bone formation induced by PGE(2) in young rats. Five- to 6-week-old rats were treated with PGE(2) (6 mg/kg/day) in the presence or absence of EP(4)A (10 mg/kg/day) for 12 days. We found that treatment with EP(4)A suppresses the increase in trabecular bone volume induced by PGE(2). This effect is accompanied by a suppression of bone formation indices: serum osteocalcin, extent of labeled surface, and extent of trabecular number, suggesting that the reduction in bone volume is due most likely to decreased bone formation. The pharmacological evidence presented here provides strong support for the hypothesis that the bone anabolic effect of PGE(2) in rats is mediated by the EP(4) receptor.

Animals↗

PubMed2001

EBNA-LP associates with cellular proteins including DNA-PK and HA95.

EBNA-LP-associated proteins were identified by sequencing proteins that immunoprecipitated with Flag epitope-tagged EBNA-LP (FLP) from lymphoblasts in which FLP was stably expressed. The association of EBNA-LP with Hsp70 (72/73) was confirmed, and sequences of DNA-PK catalytic subunit (DNA-PKcs), HA95, Hsp27, prolyl 4-hydroxylase alpha-1 subunit, alpha-tubulin, and beta-tubulin were identified. The fraction of total cellular HA95 that associated with FLP was very high, while progressively lower fractions of the total DNA-PKcs, Hsp70, Hsp 27, alpha-tubulin, and beta-tubulin specifically associated with EBNA-LP as determined by immunoblotting with antibodies to these proteins. EBNA-LP bound to two domains in the DNA-PKcs C terminus and DNA-PKcs associated with the EBNA-LP repeat domain. DNA-PKcs that was bound to EBNA-LP phosphorylated p53 or EBNA-LP in vitro, and the phosphorylation of EBNA-LP was inhibited by Wortmannin, a specific in vitro inhibitor of DNA-PKcs.

DNA-Activated Protein Kinase↗

PubMed2001

Epstein-Barr virus nuclear protein 2 has at least two N-terminal domains that mediate self-association.

Previous genetic and biochemical analyses have indicated that the Epstein-Barr virus EBNA-2 amino terminus is important for primary B-lymphocyte growth transformation and may be involved in self-association. We now report that EBNA-2 has at least two domains, amino acids 1 to 60 and 96 to 210, which independently mediate homotypic association, 1 to 60 with 1 to 60 and 96 to 210 with 96 to 210. EBNA-2 self-association is likely to be critical to the ability of EBNA-2 to interact simultaneously with multiple cellular transcription factors, coactivators, and histone acetyltransferases through its RBPJkappa binding and acidic activating domains.

Amino Acids↗