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S Harada

Publications and source records attributed to S Harada.

At least 181 records · Page 10Linked to original sources
PubMed1998

A new genetic variant in the Sp1 binding cis-element of cholecystokinin gene promoter region and relationship to alcoholism.

Neuropeptide cholecystokinin (CCK) and the CCK receptors in the central nervous system mediate actions on increasing firings, anxiety, and nociceptions. Furthermore, CCK modulates the release of dopamine and dopamine-related behaviors in the mesolimbic pathway. In our study, genetic variation in the promoter and coding regions of the prepro-CCK gene were analyzed among 66 Japanese, 66 American Whites, 54 Chinese, and 41 Colombian natives. Two nucleotide sequence variants were found: a frequent mutation at nucleotide position -45 C to T involved in core sequence of Sp1 binding cis-element of the promoter region, and a C to T substitution at the 1662 position in intron 2. Analysis for the segregation study in 10 families of twins confirmed codominant heredity of two alleles. Distribution of genotypes and gene frequencies of 66 controls and 108 alcoholics in Japan presented that allelic variant T type in alcoholics was found in higher frequencies than that of controls, and distribution of these genotypes was significantly different between the both groups.

Alcoholism↗
PubMed1998

Human immunodeficiency virus type 1 (HIV-1) infection and transcytosis activity of a HIV-1 susceptible clone from HeLa cell.

In order to clarify the transmission process of human immunodeficiency virus type 1 (HIV-1) through the epithelial cell barrier, HeLa cells susceptible and non-susceptible to HIV-1 were cloned and designated as P6 HeLa and N7 HeLa cells, respectively. P6 HeLa cells could be infected with the LAI strain of HIV-1 and mediated HIV-1 transcytosis. In contrast, N7 HeLa cells exhibited neither HIV-1 infection nor transcytosis. CD4 and galactosylceramide as the receptors for HIV-1 were not detected on P6 HeLa cells, although an anti-CD4 monoclonal antibody (mAb) blocked HIV-1 infection. Since HIV-1-infected P6 HeLa cells exhibited no fusion and survived, we speculated that the P6 HeLa cells expressed molecules other than CD4 which facilitated HIV-1 infection. Two mAbs (A-14 ITK and C57 a9-9) which inhibited the HIV-1 infection of P6 HeLa cells were generated. Each mAb recognized distinct molecule(s) as shown by Western blotting. Transcytosis by the P6 HeLa cells was inhibited by C57 a9-9 but not by A-14 ITK or anti-CD4 mAb. Both infection and transcytosis may be responsible for HIV-1 transmission through epithelial cells in a complex manner. Although infection and transcytosis occurred via different mechanisms, the molecule(s) recognized by C57 a9-9 mAb may be associated with both processes.

Antibodies, Monoclonal↗
PubMed1998

Specific and independent recognition of U3 and U5 att sites by human immunodeficiency virus type 1 integrase in vivo.

The retroviral attachment (att) sites at viral DNA ends are cis-acting regions essential for proviral integration. To investigate the sequence features of att important for human immunodeficiency virus type 1 (HIV-1) integration in vivo, we generated a series of 25 att mutants of HIV-1 by mutagenesis of the U3, U5, or both boundaries of att. Our results indicated that the terminal 11 or 12 bp of viral DNA are sufficient for specific recognition by HIV-1 integrase (IN) and suggested that IN might recognize each att site independently in vivo.

Base Sequence↗
PubMed1998

Residues 231 to 280 of the Epstein-Barr virus nuclear protein 2 are not essential for primary B-lymphocyte growth transformation.

Epstein-Barr virus (EBV) nuclear protein 2 (EBNA-2) is a transcriptional transactivator of cellular and viral gene expression and is essential for the transformation of resting human B lymphocytes into long-term lymphoblastoid cell lines (LCLs). Previous molecular genetic analyses identified three domains that are critical for transformation and showed that the rest of EBNA-2 is not critical. We now find that codons 231 to 280 that were part of one of the critical domains (J. I. Cohen, F. Wang, and E. Kieff, J. Virol. 65:2545-2554, 1991) can be deleted with only a small effect on the ability of EBNA-2 to transactivate gene expression. In transient transfection assays, EBNA-2 deleted for codons 231 to 280 accumulated to higher levels and was similar to wild-type EBNA-2 in activation of the BamC promoter and in association with RBPJk, a cellular transcription factor that is important for EBNA-2 interaction with promoter regulatory elements. However, EBNA-2 d231-280 activated the viral latent membrane protein 1 (LMP1) promoter with only 60% of wild-type efficiency. Recombinant EBVs specifically deleted for EBNA-2 codons 231 to 280 were efficient in initiating the transformation of resting primary human B lymphocytes into LCLs. However, these LCLs grew less well than wild-type EBV-transformed LCLs, and 4- to 10-fold more cells were required for outgrowth following limit dilution. EBNA-2 d231-280 accumulated to unusually high levels in the recombinant transformed LCLs, and this was associated with somewhat higher EBNA-1 and lower LMP1 expression, consistent with the near-wild-type activation of the BamC EBNA promoter and the abnormally low activation of the LMP1 promoter in transient transfection assays. Thus, EBNA-2 d231-280 modestly perturbed the regulation of viral gene expression and resulted in less LMP1, while having surprisingly subtle effects on LCL outgrowth. Deletion of EBNA-2 codons 292 to 310, which are closer to the site that specifies interaction with RBPJk, was more disruptive of RBPJk association and of the ability to transform B lymphocytes.

B-Lymphocytes↗
PubMed1998

Antisense oligonucleotides targeting c-fos mRNA inhibit rheumatoid synovial fibroblast proliferation.

OBJECTIVE: To determine whether antisense oligonucleotides targeting c-fos mRNA have the ability to inhibit the growth of interleukin 1 (IL1) stimulated fibroblast-like cells from the synovium in rheumatoid arthritis (RA). METHODS: Fibroblast-like cells established from RA synovium were stimulated by IL1 with antisense or sense oligonucleotides complementary to c-fos mRNA, and the proliferation of these cells was determined by 3H-thymidine incorporation. Effect of antisense oligonucleotides on expression of activator protein 1 (AP1) activity was evaluated using electrophoretic mobility shift assay. RESULTS: C-fos antisense oligonucleotides inhibited IL1 stimulated synovial fibroblast proliferation. The expression of AP1 activity induced by IL1 was suppressed by treatment with antisense oligonucleotides. CONCLUSION: These results suggest the feasibility of antisense strategies designed to suppress c-fos expression as therapeutic agents for RA.

Arthritis, Rheumatoid↗
PubMed1998

Relationship between alcoholism and CYP2E1 C/D polymorphism.

The genotypes of the CYP2E1 loci of 35 alcoholic and 130 nonalcoholic (healthy controls) Japanese were investigated to determine the relationship between CYP2E1 (C/D) polymorphism and susceptibility to alcohol dependence. There was a significant (d.f. = 1, chi2 = 11.0, p < 0.001) difference in the CYP2E1 C gene frequency between alcohol dependents (0.41) and controls (0.28), suggesting that the C gene of CYP2E1 may be related to the risk of developing alcoholism in Japanese, whereas the frequency of the D gene was higher among controls than alcoholics. Healthy Japanese controls showed a significantly (d.f. = 1, chi2 = 30.1, p < 0.001) higher frequency of the C allele than Swedish healthy controls (0. 10) did.

Adult↗
PubMed1998

Functional properties of jaw and tongue muscles in rats fed a liquid diet after being weaned.

Decreased masticatory demands due to liquid or soft diets cause a reduction in the growth of craniofacial bones and in the development of feeding musculature, but the effects on masticatory function and jaw/tongue muscle activities are unclear. The present study was undertaken to test the hypotheses that a liquid diet feeding after weaning affects the critical-period programming of mastication and the motor performances of jaw and tongue muscles. Thirty-six male Wistar rats were divided into two equals groups at weaning and fed either a solid (solid-diet group) or a liquid (liquid-diet group) diet until they reached 50 days of age. Electromyograms (EMG) of the masseter, medial pterygoid, temporalis, anterior digastric, styloglossus, and genioglossus were recorded while animals were naturally ingesting ordinary pellets, apple cubes, and a liquid diet. It was found that: (1) a more irregular chewing rhythm, a shorter chewing sequence, and a longer chewing cycle were found in the liquid-diet group, but there were no differences observed during lapping/licking between the two groups; (2) during the chewing cycles, the EMG onset of each muscle in relation to that of the masseter in the liquid-diet group was similar to that in the lapping/licking cycles in both groups; (3) the activities of jaw elevators (masseter, medial pterygoid, and temporalis) during the chewing cycles were significantly higher in the liquid-diet group; and (4) the increase in the EMG activities of jaw elevators during pellet chewing compared with apple cube chewing was significantly weaker in the liquid-diet group, whereas such an enhancement was found simultaneously in the styloglossus in the solid-diet group, and in the anterior digastric in the liquid-diet group. These findings verify that: (1) the motor output of jaw and tongue muscles may be altered in rats fed a liquid diet after being weaned; (2) the feeding of a liquid diet to rats after being weaned may obstruct the functional transition from suckling to mastication; and (3) jaw elevators that develop without motor learning of mastication are inefficiency when performing functionally.

Analysis of Variance↗
PubMed1998

Biochemical characterization of recombinant HIV-1 reverse transcriptase (rRT) as a glycyrrhizin-binding protein and the CK-II-mediated stimulation of rRT activity potently inhibited by glycyrrhetinic acid derivative.

By means of successive Mono Q and glycyrrhizin (GL)-affinity column chromatography (HPLC), recombinant HIV-1 RT (rRT) was purified to apparent homogeneity from the Superdex 200 pg fraction of the crude protein extract of E. coli BL21 transfected with pET 21a(+)/HIV-1 PR-RT. It was found that (i) rRT functioned as an effective phosphate acceptor for recombinant human casein kinase II (rhCK-II) in vitro; (ii) this phosphorylation was inhibited by anti-HIV-1 substances [a glycyrrhetinic acid derivative (oGA) and quercetin] and a high dose (100 microM) of GL; (iii) RNA-dependent DNA polymerase (RDDP) activity was stimulated about 2.5-fold after full phosphorylation of rRT by rhCK-II; and (iv) oGA as well as NCS-chromophore effectively prevented the CK-II-mediated stimulation of RDDP activity. These results suggest that the anti-HIV-1 effect of oGA may be involved in the selective inhibition of the CK-II-mediated stimulation of HIV-1 RT at the cellular level.

Anti-HIV Agents↗
PubMed1998

Reversible hypothyroidism in empty sella syndrome: a case report.

A 33 year-old Japanese woman complained of generalized fatigue, recurrent infections and gradual weight loss 1 year after her first delivery. During delivery, no excessive bleeding or change in blood pressure was noted. On endocrinologic examination 2 years after delivery, she was found to have severe adrenal insufficiency and hypothyroidism. Pituitary function tests revealed impaired responses of ACTH, PRL and gonadotropins, and normal response of GH. TSH response to TRH was delayed but not exaggerated. Cranial magnetic resonance imaging showed an empty sella. The adrenal glands were responsive to extrinsic ACTH, and adequately accumulated 123I-aldosterol. Antipituitary and antithyroid autoantibodies were detected in her serum. She was diagnosed with partial hypopituitarism associated with empty sella syndrome. Approximately 2 months after administration of cortisone acetate 25 mg/ day her general condition was noticeably improved, with normalization of thyroid function and improvement of gonadotropin responses to GnRH. This case suggests that a physiologic dose of glucocorticoid is necessary to maintain not only thyroid function but also some of the remaining pituitary functions in patients with empty sella syndrome manifesting hypopituitarism.

Adult↗
PubMed1998

Descriptive epidemiology of IDDM in Hokkaido, Japan: the Childhood IDDM Hokkaido Registry.

OBJECTIVE: To identify the incidence of IDDM with regard to sex, age, family history of diabetes, season, and 5-year period of childhood IDDM among children ages 0-14 years from a population-based epidemiological study in Hokkaido, Japan, from 1973 to 1992. RESEARCH DESIGN AND METHODS: Registration of all new IDDM cases in Hokkaido was conducted by the Childhood IDDM Hokkaido Registry Study Group from 1973 to 1992. The cases were selected from among 1) patients who were admitted to the member hospitals of the study group, 2) patients who answered a questionnaire distributed to hospitals and diabetic clinics throughout Hokkaido, and 3) patients whose cases were recorded in free-treatment medical records of urban and rural districts. The case ascertainment rate was estimated to be 100%. Differences in incidence with regard to sex, age, family history of diabetes, season, and year period were analyzed by the Poisson regression analysis by GENMOD. RESULTS: During the 20-year period studied, 396 cases (181 boys, 215 girls) of abrupt-onset IDDM were registered. Statistically significant differences in annual incidence were found according to sex (female), age (8-14 years), history (having no diabetes in family), season (spring), and 5-year period. CONCLUSIONS: This is the first population-based, long-term epidemiological study of childhood IDDM from Japan. We observed a significantly higher annual incidence (per 100,000/year) of IDDM in female subjects (1.81), older age-groups (2.25 for 8-14 years), subjects with no family history of diabetes (1.26), diabetes onset in the spring (2.20), and an increased trend over the 20 years. In addition, the heterogeneity of IDDM among Japanese children needs to be elucidated.

Adolescent↗
PubMed1998

Effect of sex hormones on rat liver cytosolic alcohol dehydrogenase activity.

Rat liver cytosolic alcohol dehydrogenase (ADH) activity is known to be significantly higher in females than in males. To elucidate a possible mechanism of sex difference in the ADH activities, we studied the in vivo effects of the administrations of beta-estradiol, progesterone or testosterone, and castrations (orchiectomy and ovariectomy) on the ADH activities in male and female Sprague-Dawley adult rats. Furthermore, we studied the ADH activities in six liver portions of sham-operated male, orchiectomized male, and female rats. The ADH activities were higher in orchiectomized male rats than in sham-operated male rats. These results were observed in all liver portions. The administration of testosterone (5 mg/kg BW, twice a day for 7 d) to orchiectomized male rats significantly decreased ADH activities. The ADH activities in ovariectomized female rats were comparable with those in sham-operated female rats. The administration of beta-estradiol (50 micrograms/kg BW, once every 2 d for 20 d) or progesterone (75 micrograms/kg BW, once every 2 d for 20 d) to rats increased the ADH activities in males more than in females. These results suggest that the inhibitory action of androgen and the slight facilitatory actions of progestin and estrogen are involved in the mechanism of sex difference in adult rat liver cytosolic ADH activity.

Alcohol Dehydrogenase↗
PubMed1998

Fattiviracin A1, a novel antiviral agent produced by Streptomyces microflavus strain No. 2445. II. Biological properties.

Fattiviracin A1, showed potent antiviral activities against herpes simplex virus type 1 (HSV-1), varicella-zoster virus (VZV), influenza A virus and human immunodeficiency virus type 1 (HIV-1). It showed no cytotoxicity against Vero cells. Fattiviracin A1 exhibited no significant antibacterial or antifungal activities. Treatment of HSV-1 with fattiviracin A1 decreased its infectivity to Vero cells. The mechanism of its antiviral activity may be due to inactivation of the viral particles and inhibition of viral entry into host cells.

Animals↗
PubMed1998

Epostatin, new inhibitor of dipeptidyl peptidase II, produced by Streptomyces sp. MJ995-OF5. I. Taxonomy of producing strain, fermentation, isolation, physico-chemical properties and biological properties.

A new inhibitor of dipeptidyl peptidase II (DPP-II, EC 3.4.14.2), designated as epostatin, was discovered in the fermentation broth of a strain isolated in our institute. The strain has been identified as Streptomyces sp. MJ995-OF5 on the basis of taxonomic studies. Epostatin was obtained as a yellow powder after seqential purification by chromatography on Diaion HP-20, n-butanol extraction, Sephadex LH-20 column chromatography and centrifugal partition chromatography (CPC). Epostatin inhibited DPP-II competitively in a dose dependent manner. The compound was slightly inhibitory against other dipeptidyl peptidases.

Alanine↗
PubMed1998

Fluostatins A and B, new inhibitors of dipeptidyl peptidase III, produced by Streptomyces sp. TA-3391. I. Taxonomy of producing strain, production, isolation, physico-chemical properties and biological properties.

New inhibitors of dipeptidyl peptidaseIII (EC 3.4.14.4) from human placenta, designated as fluostatins A and B, were discovered in the fermentation broth of a strain isolated in our institute. The strain has been identified as Streptomyces sp. TA-3391 on the basis of taxonomic studies. Fluostatins A and B were purified by Diaion HP-20 chromatography, ethyl acetate extraction, silica gel chromatography and reverse phase preparative HPLC. With the synthetic substrate, arginyl-arginine-2-naphthylamide, the IC50 values of fluostatins A and B were 0.44 and 24.0 micrograms/ml, respectively. Fluostatins A and B were slightly inhibitory against other dipeptidyl peptidases. Fluostatin A showed mixed-type (competitive and noncompeptitive) inhibition with human leucine-enkephalin as a substrate, and the inhibition constant (Ki) was 14.2 microM.

Chromatography, High Pressure Liquid↗
PubMed1998

Study on Parkinson's disease and alcohol drinking.

To clarify alcohol drinking habits of patients with Parkinson's disease (PD) in Japanese, we compared mean values of alcohol consumption of PD patients and controls with special references to genetic polymorphism of ALDH2. Ninety-three Japanese outpatients with PD (39 males, 54 females) diagnosed by three skilled neurologists from 4 hospitals in Kanto area were analyzed for ALDH2 genotypes and alcohol consumption. A total of 297 healthy controls (156 males, 141 females) in the same area were also analyzed. PCR- SSCP (polymerase chain reaction-single strand conformational change polymorphism) analysis was used to determine ALDH2 genotypes. Mean values of alcohol consumption (ethanol g/month/person) from patients with PD were estimated by direct interview, and those from controls were obtained by questionnaire. Distributions of three genotypes and allele frequencies of ALDH2 were not different between patients and controls, however mean values of alcohol consumption of PD group were significantly lower than those of control group when compared between the same ALDH2 genotype. Our data suggested that the lower values of alcohol consumption in patients with PD for every ALDH2 genotypes may be caused by other factors such as premorbid personality rather than ALDH2 variant.

Aged↗
PubMed1998

[Genetic polymorphism of human CYP2E1: new allels detected in exons and exon-intron junctions].

Cytochrome P450-2E1 (CYP2E1) is a major component of the microsomal ethanol-oxidizing system (MEOS) and is also involved in the metabolism of a variety of foreign compounds including carcinogens. It has been shown that there is an interindividual variation in the expression of human hepatic CYP2E1. Gene-environmental interactions have been suggested to account for the difference. In this study, we screened nine exons of the human CYP2E1 gene for detecting allelic variants in genomic DNA samples obtained from 115 Japanese controls, 96 Japanese alcoholics and 124 American control subjects. A novel missense mutation in exon 2 (V72L) was found in Japanese controls, and another missense mutation in exon 8 (D394G) was detected in American Caucasians. In addition, two novel silent mutations in exon 6 (T303T) and exon 8 (F420F) were found in Japanese controls and alcoholics. Especially the silent mutation in exon 8 was highly polymorphic among three population groups. The mutation in exon 2 (V72L) was detected only in Japanese controls, but not in alcoholics although it shows no significant difference. Gene frequency of the silent mutation in exon 8 was significantly higher in Japanese than American Caucasians (34.8% vs 21.0%, p < 0.02). Our data indicated that nucleotide replacement in the open reading frame is no major factor responsible for alcoholism. However, functional significance of the two novel missense mutations remains to be detailed.

Alcoholism↗
PubMed1998

[Investigation for polymorphism of ALDH2 exon12 in several Asian areas].

Mitochondrial aldehyde dehydrogenase (ALDH2) shows genetic polymorphism (Glu487Lys substitution) among Mongoloid populations, and the substitution is responsible for flushing symptom after alcohol intake. Recently, new ALDH2 alleles (ALDH2*3 and ALDH2*2Taiwan) in exon12 were reported in North American Indians and in Chinese from Taiwan by Novoradskey et al (1995). In the present study, we investigated the new allelic variants in exon12 for the five different ethnic groups (Mongolian, North Chinese, South Chinese, Myanmar, Japanese) by using PCR-SSCP and PCR-direct sequencing. Also, Glu 487 Lys substitution was analyzed to obtain additional information on gene geography of ALDH2 alleles in Asia reported so far. No new variants were found in the five population groups, but ALDH2*2 allele showed different frequencies among these groups. Especially, the frequencies of ALDH2*2 in Myanmer (0.02) and Mongolian (0.05) were significantly lower than other populations.

Aldehyde Dehydrogenase↗