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Y Ban

Publications and source records attributed to Y Ban.

At least 73 records · Page 4Linked to original sources
PubMed2002

Study of CP-violating asymmetries in B0-->pi(+)pi(-) decays.

We present a measurement of CP-violating asymmetries in B0-->pi(+)pi(-) decays based on a 41.8 fb(-1) data sample collected at the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider. We fully reconstruct one neutral B meson as a B0-->pi(+)pi(-) CP eigenstate and identify the flavor of the accompanying B meson from its decay products. From the asymmetry in the distribution of the time intervals between the two B meson decay points, we obtain the CP-violating asymmetry parameters S(pipi)=-1.21(+0.38)(-0.27)(stat)+0.16-0.13(syst) and A(pipi)=+0.94(+0.25)(-0.31)(stat)+/-0.09(syst).

Journal Article↗
PubMed2002

Observation of chi(c2) production in B meson decay.

We report the first observation of chi(c2) production in B meson decays. We find an inclusive B-->chi(c2)X branching fraction of (1.80(+0.23)(-0.28)+/-0.26) x 10(-3). The data set, collected with the Belle detector at the KEKB e(+)e(-) collider, consists of 31.9 x 10(6) BB events. We also present branching fractions and momentum spectra for both chi(c1) and chi(c2) production.

Journal Article↗
PubMed2002

Observation of B(+/-) --> p(-)pK(+/-).

We report the observation of the decay mode B(+/-) --> p(-)pK(+/-)based on an analysis of 29.4 fb(-1) of data collected by the Belle detector at KEKB. This is the first example of a b-->s transition with baryons in the final state. The p(-)p mass spectrum in this decay is inconsistent with phase space and is peaked at low mass. The branching fraction for this decay is measured to be B(B+/--->p(-)pK+/-) = [4.3(+1.1)(-0.9)(stat)+/-0.5(syst)]x 10(-6). We also report upper limits for the decays B(0)-->p(-)pK(S) and B(+/-)-->p(-)p pi(+/-).

Journal Article↗
PubMed2002

Precise measurement of B meson lifetimes with hadronic decay final states.

The lifetimes of the B(0) and B- mesons are extracted from 29.1 fb(-1) of data collected with the Belle detector at the KEK B factory. A fit to the decay length differences of neutral and charged B meson pairs, measured in events where one of the B mesons is fully reconstructed in several hadronic modes, yields tau(B(0)) = 1.554+/-0.030(stat)+/-0.019(syst) ps, tau(B-) = 1.695+/-0.026(stat)+/-0.015(syst) ps, and tau(B-)/tau(B(0)) = 1.091+/-0.023(stat)+/-0.014(syst).

Journal Article↗
PubMed2002

Measurement of the lifetime difference in D0 meson decays.

We report a measurement of the D0-D macro(0) mixing parameter y(CP) using 23.4 fb(-1) of data collected near the Upsilon(4S) resonance with the Belle detector at KEKB. y(CP) is measured from the lifetime difference of D0 mesons decaying into the K(-)pi(+) state and the CP-even eigenstate K(-)K(+). We find y(CP) = (-0.5+/-1.0(+0.7)(-0.8))x10(-2), where the first error is statistical and the second is systematic, corresponding to a 95% confidence interval -0.030<y(CP)<0.020.

Journal Article↗
PubMed2002

Production of prompt charmonia in e(+)e(-) annihilation at square root of s approximately equals 0.6 GeV.

The production of prompt J/psi, psi(2S), chi(c1), and chi(c2) is studied using a 32.4 fb(-1) data sample collected with the Belle detector at Upsilon(4S) and at 60 MeV below the resonance. The yield of prompt J/psi mesons in the Upsilon(4S) sample is compatible with that of continuum production; we set an upper limit B(Upsilon(4S)-->J/psiX) < 1.9 x 10(-4) at the 95% confidence level, and find sigma(e(+)e(-)-->J/psiX) = 1.47 plus/minus 0.10 plus/minus 0.13 pb. The cross sections for prompt psi(2S) and direct J/psi are measured. The J/psi momentum spectrum, production angle distribution, and polarization are studied.

Journal Article↗
PubMed2001

Vitamin D receptor initiation codon polymorphism influences genetic susceptibility to type 1 diabetes mellitus in the Japanese population.

BACKGROUND: Vitamin D has been shown to exert manifold immunomodulatory effects. Type 1 diabetes mellitus (T1DM) is regarded to be immune-mediated and vitamin D prevents the development of diabetes in the NOD mouse. We studied the association between T1DM and the initiation codon polymorphism in exon 2 of the vitamin D receptor gene in a Japanese population. We also investigated associations between the vitamin D receptor polymorphism and GAD65-antibody (Ab) positivity. We carried out polymerase chain reaction-restriction fragment length polymorphism analysis in 110 Japanese T1DM patients and 250 control subjects. GAD65 antibodies were assessed in 78 patients with T1DM. RESULTS: We found a significantly higher prevalence of the F allele / the FF genotype in the patients compared to the controls (P = 0.0069 and P = 0.014, respectively). Genotype and allele frequencies differed significantly between GAD65-Ab-positive patients and controls (P = 0.017 and P = 0.012, respectively), but neither between GAD65-Ab-negative patients and controls (P = 0.68 and P = 0.66, respectively) nor between GAD65-Ab-positive and -negative patients (P = 0.19 and P = 0.16, respectively). CONCLUSIONS: Our findings suggest that the vitamin D receptor initiation codon polymorphism influences genetic susceptibility to T1DM among the Japanese. This polymorphism is also associated with GAD65-Ab-positive T1DM, although the absence of a significant difference between GAD65-Ab-negative patients and controls might be simply due to the small sample size of patients tested for GAD65 antibodies.

Journal Article↗
PubMed2001

Lack of association between estrogen receptor beta dinucleotide repeat polymorphism and autoimmune thyroid diseases in Japanese patients.

BACKGROUND: The autoimmune thyroid diseases (AITDs), such as Graves' disease (GD) and Hashimoto's thyroiditis (HT), appear to develop as a result of complex interactions between predisposing genes and environmental triggers. Susceptibility to AITDs is conferred by genes in the human leukocyte antigen (HLA) and genes unlinked to HLA, including the CTLA-4 gene. Recently, estrogen receptor (ER) beta, located at human chromosome 14q23-24.1, was identified. We analyzed a dinucleotide (CA)n repeat polymorphism located in the flanking region of ERbeta gene in patients with AITDs and in normal subjects. High heterozygosity makes this polymorphism a useful marker in the genetic study of disorders affecting female endocrine systems. We also correlated a ERbeta gene microsatellite polymorphism with bone mineral density (BMD) in the distal radius and biochemical markers of bone turnover in patients with GD in remission. RESULTS: Fourteen different alleles were found in 133 patients with GD, 114 patients with HT, and 179 controls subjects. The various alleles were designated as allele*1 through allele*14 according to the number of the repeats, from 18 to 30. There was no significant difference in the distributions of ERbeta alleles between patient groups and controls. Although recent study demonstrated a significant relation between a allele*9 in the ERbeta gene and BMD in postmenopausal Japanese women, there were no statistically significant interaction between this allele and BMD in the distal radius, nor biochemical markers in patients with GD in remission. CONCLUSIONS: The present results do not support an association between the ERbeta microsatellite marker and AITD in the Japanese population. We also suggest that the ERbeta microsatellite polymorphism has at most a minor pathogenic importance in predicting the risk of osteoporosis as a complication of GD.

Journal Article↗
PubMed2001

Developmental toxicity of orally administered thiabendazole in ICR mice.

Thiabendazole (TBZ) is a potent anthelmintic and fungicide used in the treatment of parasitic infections in humans and domestic animals and post-harvest protection of agricultural commodities. TBZ is not teratogenic or selectively foetotoxic in rats or rabbits, in contrast to several other benzimidazole derivatives. However, when administered orally to pregnant (Jcl:ICR) mice at lethal dosages, malformations were observed in treated fetuses. To assess whether the effects found in this previous study were attributable to maternal toxicity or TBZ the present study was conducted. TBZ doses of 25, 100 or 200 mg/kg/day were selected based on a preliminary range-finding study in which maternotoxicity was evident at doses of 200 mg/kg/day or above. The compound was administered during gestation days 6-15 as a solution in olive oil. Caesarean sections were completed on gestation day 18 and complete fetal examinations conducted. Decreases in maternal weight gain relative to controls were found at doses of 100 mg/kg/day or above, which paralleled decreases in foetal weights in these same dose groups. However, there were no treatment-related external, visceral or skeletal anomalies in any treatment group. Therefore, TBZ was not teratogenic or selectively foetotoxic in mice, with no-observed-effect levels (NOEL) of 25 and greater than 200 mg/kg/day for maternal and fetal weight effects and teratogenicity, respectively. These results indicate that foetal effects noted in previous studies in mice were probably secondary to severe maternal toxicity.

Abnormalities, Drug-Induced↗
PubMed2001

Toxic multinodular goitre in a patient with generalized resistance to thyroid hormone who harbours the R429Q mutation in the thyroid hormone receptor beta gene.

The association of resistance to thyroid hormone (RTH) due to a receptor defect with toxic multinodular goitre or with carcinoma of the thyroid has not been previously reported. Previous histopathological studies of the thyroid gland in patients with RTH have revealed changes similar to multinodular goitre, probably due to continuous stimulation by TSH. We report here a case of generalized resistance to thyroid hormone associated with a multinodular goitre, which became toxic. The patient was a 46-year-old Japanese woman who noticed a goitre although she had no symptoms of thyrotoxicosis. Initial examination revealed elevated serum thyroid hormone levels and a normal TSH level. Ultrasonography disclosed a multinodular goitre with cystic lesions. Three years later, the patient complained that the goitre had become larger and that she had developed symptoms of thyrotoxicosis such as palpitation and hyperhydrosis. Progressive hyperthyroxinaemia with relatively suppressed TSH, increased radioiodine uptake and negative anti-TSH receptor antibodies led to the diagnosis of toxic multinodular goitre. Subtotal thyroidectomy was performed, and pathological examination revealed a micropapillary carcinoma within the multinodular goitre. Occurrence of thyroid carcinoma should be considered in RTH because its incidence is high in multinodular goitre. Molecular examination revealed the R429Q mutation in the thyroid hormone receptor beta gene, which is one of the mutations usually manifesting as the pituitary resistance phenotype. That thyrotoxic manifestations appeared only during toxic stage of multinodular goitre in this case suggests that the phenotype of this type of mutation can be dependent on the amount of thyroid hormone.

Amino Acids↗
PubMed2001

Association of the mitochondrial DNA 5178A/C polymorphism with maternal inheritance and onset of type 2 diabetes in Japanese patients.

The mitochondrial DNA 5178A/C (mt5178A/C) polymorphism is associated with longevity and adult onset diseases. We investigated an association of the mt5178A/C polymorphism with the occurrence and clinical features of type 2 diabetes. Two hundred and seventy Japanese patients with type 2 diabetes (181 men and 89 women) and 254 control subjects without diabetes were studied. Patients with mutations at position 3243 in the mitochondrial DNA were excluded. Genotype was determined by the polymerase chain reaction-restriction fragment length polymorphism method. Various clinical features including age at disease onset were compared between the patients with the mt5178A and mt5178C alleles. Mt5178C was observed more frequently in patients with type 2 diabetes than in control subjects (65.9% vs 57.9%, P = 0.058). Clear information about the maternal history of diabetes was obtained from 233 diabetic patients. Patients with a maternal history of diabetes carried the mt5178C allele (58/75, 77.3%) more frequently than did patients without a maternal history of diabetes (100/158, 63.3%; P = 0.032) and control subjects (57.9%; P = 0.002). The mean age at onset of diabetes was significantly lower in patients with mt5178C (47.6 +/- 11.4 years) than in patients with mt5178A (51.5 +/- 10.0 years; P = 0.0073). The mt5178A/C polymorphism may be associated with maternal inheritance of type 2 diabetes and may influence the age at onset through deterioration of mitochondrial function.

Adolescent↗
PubMed2001

SEL1L microsatellite polymorphism in Japanese patients with autoimmune thyroid diseases.

The autoimmune thyroid diseases (AITDs), comprising Graves' disease (GD) and Hashimoto's thyroiditis (HT), appear to develop as a result of complex interactions between predisposing genes and environmental triggers. A recently performed genome-wide linkage study identified six loci that showed evidence for linkage to AITD. One locus, GD-1, on chromosome 14q31 was mapped to within 2 centimorgans (cM) of the recently reported multinodular goiter (MNG)-1 locus. Furthermore, microsatellite markers for the thyroid stimulating hormone receptor gene on chromosome 14q31 were associated with AITDs in the Japanese population. A newly isolated growth factor, SEL1L, was recently mapped to 14q31, and we considered it an interesting candidate gene to examine with respect to both GD and MNG. We therefore have analyzed a dinucleotide (CA)n repeat polymorphism in the intron 20 of the SEL1L gene in patients with AITDs and in normal subjects. The polymorphic marker was analyzed by polymerase chain reaction (PCR) followed by electrophoresis on denaturing polyacrylamide gels. There was no significant difference in the distributions of SEL1L alleles between patients and controls. The present results do not support an association between a dinucleotide repeat polymorphism in intron 20 of the SEL1L gene and AITD in Japanese women.

Female↗
PubMed2001

Aldosterone-producing adenoma with prolonged amelioration by dexamethasone.

Secretion of aldosterone from aldosterone-producing adenoma (APA) is to some degree under the control of ACTH and the suppressible effect of glucocorticoid on plasma aldosterone concentration (PAC) and blood pressure has been reported to be transient. We report a rare case of aldosteronism due to APA in which PAC and blood pressure were well controlled with small dose dexamethasone for over one year. No chimeric gene of glucocorticoid-remediable aldosteronism (GRA) was found in DNA of APA and leukocytes from peripheral blood and 17alpha-hydroxylase deficiency (17-OH-D) was ruled out by endocrinological examinations, this case indicates the possibility of an unknown mechanism of ACTH-dependent APA.

Adenoma↗
PubMed2001

Corticotroph cell adenoma without typical manifestations of Cushing's disease presenting with cavernous sinus syndrome following pituitary apoplexy.

This report presents a unique case of corticotroph cell adenoma in a 30-year-old man without acromegaly or features typical of Cushing's disease, who developed cavernous sinus syndrome following pituitary apoplexy. Magnetic resonance imaging revealed a large intrasellar/suprasellar mass with pituitary hemorrhage and extension of a hematoma to the anterior base of the skull. Urgent transnasal pituitary surgery revealed an acidophilic pituitary adenoma, with immunoreactivity for ACTH and GH and expression of proopiomelanocortin (POMC) and GH messenger ribonucleic acid (mRNA) demonstrated by in situ hybridization. To our knowledge, a silent corticotroph cell adenoma with GH production has never been reported. This type of adenoma may potentially enlarge and develop tumoral hemorrhage because it is free of endocrinological symptoms.

Adenoma↗
PubMed2001

Production of 8-OHdG and cytochrome c by cultured human mononuclear cells in patients with autoimmune thyroid disease.

Since oxidative stress is related to autoimmune thyroid disease, we studied the production of 8-hydroxy-2'-deoxyguanosine (8-OHdG) and cytochrome c by culture of mononuclear cells from patients with Graves' disease and Hashimoto's thyroiditis. In patients with untreated Graves' disease, 8-OHdG and cytochrome c levels in culture supernatant of mononuclear cells were significantly higher than those of healthy control subjects, while the cytochrome c levels were significantly higher in patients with untreated Graves' disease and Hashimoto's thyroiditis than those of control subjects. Significant correlations between 8-OHdG and FT4, and cytochrome c were found. These results indicated that thyroid function has a potent influence on oxidative stress.

8-Hydroxy-2'-Deoxyguanosine↗
PubMed2001

Angiographic classification of coronary dissections after plain old balloon angioplasty for prediction of regression at follow-up.

Coronary dissection after plain old balloon angioplasty often shows regression during follow-up. This study sought to determine whether we can predict such phenomenon angiographically. We analyzed 64 patients with 71 type B-D coronary dissections determined by the National, Heart, Lung, and Blood Institute (NHLBI) criteria. Regression was considered present when minimal lumen diameter increased by more than 0.3 mm during follow-up. Dissections were divided into subgroups using the NHLBI criteria and our classification in which type a and b dissections were characterized by the width of a dissection lumen exceeding one quarter of the reference diameter with the outer edge of the dissection lumen within the boundary of reference in type a and beyond it in type b. In type c and type d dissections, the width of the dissection lumen was within one quarter of the reference with its outer edge within the boundary of reference in type c and beyond it in type d. Type e dissection had a protruding flap or spiral appearance. Regression was recognized in 23.9%. The distribution of dissection types was similar in the groups with and without regression by the NHLBI criteria, but type c dissection had regression more frequently than the other types of coronary dissections (p<0.001) using our classification.

Aged↗