Biomedical subjects

Yoshiyuki Ban

Publications and source records attributed to Yoshiyuki Ban.

At least 19 recordsLinked to original sources

PubMed2006

Impact of increased plasma serotonin levels and carotid atherosclerosis on vascular dementia.

Serotonin (5-HT), a potent vasoconstrictor in the large cerebral arteries, is considered to play a key role in atherothrombosis and to be implicated in ischemic cerebrovascular events followed by delayed neuronal death. The present study aims at evaluating the relationship between plasma levels of 5-HT and vascular dementia (VaD) caused by stroke or atherosclerotic small vessel disease. Carotid artery intima-media thickness (IMT), plaques, plasma 5-HT levels and atherosclerotic parameters were determined in 20 patients with VaD and 40 age-matched controls. Age, gender, body mass index, systolic and diastolic blood pressure, fasting plasma glucose levels and serum levels of insulin, triglycerides, high-density lipoprotein cholesterol, leptin, adiponectin and interleukin-6 and plasma levels of plasminogen activator inhibitor-1 were not significantly different between the two groups. Serum levels of insulin-like growth factor-1 (IGF-1) were significantly lower in VaD patients than in controls. Plasma 5-HT levels, serum levels of hepatocyte growth factor (HGF), low-density lipoprotein (LDL) cholesterol and high-sensitive C-reactive protein (hs-CRP), max IMT and plaque frequency were significantly greater in VaD patients than in controls. There was a significant positive correlation of max IMT with 5-HT or HGF levels. Multiple logistic regression analysis revealed that increased plasma levels of 5-HT and carotid plaque prevalence had significantly independent association with VaD as compared with serum levels of IGF-1, HGF, LDL cholesterol and hs-CRP. These results suggest that increased plasma levels of 5-HT and carotid atherosclerotic plaques may be involved in the pathogenesis and progression of VaD.

Aged↗

PubMed2006

[Thyroid cyst].

Explore the source record for details and available documents.

Biopsy, Fine-Needle↗

PubMed2006

Possible interaction between HLA-DRbeta1 and thyroglobulin variants in Graves' disease.

Graves' disease (GD) is influenced by two major susceptibility loci, HLA-DR3 and thyroglobulin (Tg). Recently we have shown that specific HLA-DR and Tg gene sequences predispose to Graves' disease. Individuals carrying at least one arginine at position 74 of the DRbeta1 chain (denoted the R- genotype) have a significantly increased risk of GD, as do individuals homozygous for the single nucleotide protein (SNP) in exon 33 of the Tg gene (denoted the CC genotype). Therefore, for the current study we hypothesized that these two genes may interact to influence the etiology of GD. To test this hypothesis, we analyzed the genotypes of 185 Caucasian patients with GD and 143 Caucasian controls for both genes. We tested for an interaction effect, that is, is one gene's effect on GD greater when the other gene is also present than when the other gene is absent? A logistic regression analysis yielded an estimate of 4.31 for the interaction term (p = 0.053). Our results may suggest an interaction between the R- and CC variants in conferring susceptibility to GD. These results, if confirmed, may imply that these two variants interact biologically to increase the odds of GD.

Adult↗

PubMed2006

Association of a C/T single-nucleotide polymorphism in the 5' untranslated region of the CD40 gene with Graves' disease in Japanese.

CONTEXT: Graves' disease (GD) is caused by an interplay of genetic factors and environmental triggers. Recently, a susceptibility locus for GD was mapped to chromosome 20q11 (GD-2). Furthermore, a novel single nucleotide polymorphism (SNP) in the CD40 gene, which is located in 20q11, was found to be associated and linked with GD in Caucasians and in Koreans. OBJECTIVES: To examine a C/T SNP in the 5' untranslated region of the CD40 gene (CD40-E1SNP) for association with autoimmune thyroid diseases (AITDs) in a Japanese dataset. DESIGN, SETTING, AND PATIENTS: Case-control association studies were performed using the CD40-E1SNP. We studied 485 Japanese patients with AITD (301 with GD, 184 with Hashimoto's thyroiditis [HT]) and 177 matched Japanese control subjects in association studies. MAIN OUTCOME: Frequencies of genotypes and alleles of the CD40- E1SNP. RESULTS: The distribution of genotype frequencies differed significantly between patients with GD and controls in a dominant manner (p = 0.039). The CC+CT genotypes of the CD40-E1SNP were associated with the increased risk for GD (p = 0.015, odds ratio [OR] = 1.9). In contrast, no differences in genotype frequencies were observed between HT patients and controls for the CD40-E1SNP. CONCLUSION: These results suggested that the CD40 gene is involved in susceptibility for GD in the Japanese.

5' Untranslated Regions↗

PubMed2005

Genetic analysis of families with autoimmune diabetes and thyroiditis: evidence for common and unique genes.

CONTEXT: Epidemiological data suggest a common genetic susceptibility to type 1 diabetes (T1D) and autoimmune thyroid disease (AITD). OBJECTIVE: Our objective was to identify the joint susceptibility genes for T1D and AITD. DESIGN: We conducted a family-based linkage and association study. SETTING: The study took place at an academic medical center. PARTICIPANTS: Participants included 55 multiplex families (290 individuals) in which T1D and AITD clustered (T1D-AITD families). MAIN OUTCOME MEASURES: We conducted tests for linkage and family-based associations (transmission disequilibrium test) with four candidate genes: human leukocyte antigen (HLA), cytotoxic T lymphocyte-associated antigen 4 (CTLA-4), insulin variable number of tandem repeats (VNTR), and thyroglobulin. RESULTS: Linkage evidence to HLA appeared when subjects with either T1D or AITD were considered affected [maximum LOD score (MLS), 2.2]. The major HLA haplotype contributing to the shared susceptibility was DR3-DQB1*0201, with DR3 conferring most of the shared risk. The CTLA-4 gene showed evidence for linkage only when individuals with both T1D and AITD were considered affected (MLS, 1.7), and the insulin VNTR showed evidence for linkage when individuals with either T1D or AITD were considered affected (MLS, 1.9); i.e. it may contribute to the familial aggregation of T1D and AITD. CONCLUSIONS: The HLA class II locus contributes to the shared risk for T1D and AITD, and the major HLA haplotype contributing to this association is DR3-DQB1*0201. Additional non-HLA loci contribute to the joint susceptibility to T1D and AITD, and two potential candidates include the CTLA-4 and insulin VNTR loci.

Adult↗

PubMed2005

Association of a CTLA-4 3' untranslated region (CT60) single nucleotide polymorphism with autoimmune thyroid disease in the Japanese population.

The etiology of the autoimmune thyroid diseases (AITDs), Graves' disease (GD) and Hashimoto's thyroiditis is largely unknown. However, genetic susceptibility is believed to play a major role. The cytotoxic T-lymphocyte antigen-4 (CTLA-4) gene, encoding a negative regulator of the T-lymphocyte immune response, had been reported to be associated and/or linked to AITD. Recently, AITD susceptibility in the Caucasians was mapped to the 6.1-kb 3'UTR of the CTLA-4 gene, in which the single-nucleotide polymorphism (SNP), CT60, was most strongly associated with AITD. In order to determine the association of the CTLA-4 gene with AITD in the Japanese, case-control association analysis for the CT60 of the CTLA-4 gene using 264 AITD patients and 179 healthy controls was done. The frequency of the disease-susceptible G allele of the CT60 of the Japanese control was higher than that of the Caucasians (72.6 vs. 52.3%). However, the G allele of the CT60 was associated with GD (84.0 vs. 72.6%, P=0.0008) and AITD (80.1 vs. 72.6%, P=0.009) in the Japanese. Furthermore, the G allele of the CT60 was associated with the increased risk for GD [P=0.004, odds ratio (OR)=2.0] and AITD (P=0.03,OR=1.6) in a recessive model. These results suggested that the CTLA-4 gene is involved in the susceptibility for GD and AITD in the Japanese.

3' Untranslated Regions↗

PubMed2005

Susceptibility genes in thyroid autoimmunity.

The autoimmune thyroid diseases (AITD) are complex diseases which are caused by an interaction between susceptibility genes and environmental triggers. Genetic susceptibility in combination with external factors (e.g. dietary iodine) is believed to initiate the autoimmune response to thyroid antigens. Abundant epidemiological data, including family and twin studies, point to a strong genetic influence on the development of AITD. Various techniques have been employed to identify the genes contributing to the etiology of AITD, including candidate gene analysis and whole genome screening. These studies have enabled the identification of several loci (genetic regions) that are linked with AITD, and in some of these loci, putative AITD susceptibility genes have been identified. Some of these genes/loci are unique to Graves' disease (GD) and Hashimoto's thyroiditis (HT) and some are common to both the diseases, indicating that there is a shared genetic susceptibility to GD and HT. The putative GD and HT susceptibility genes include both immune modifying genes (e.g. HLA, CTLA-4) and thyroid specific genes (e.g. TSHR, Tg). Most likely, these loci interact and their interactions may influence disease phenotype and severity.

Autoimmune Diseases↗

PubMed2005

The codon 620 single nucleotide polymorphism of the protein tyrosine phosphatase-22 gene does not contribute to autoimmune thyroid disease susceptibility in the Japanese.

The etiology of the autoimmune thyroid diseases (AITDs), Graves' disease (GD), and Hashimoto's thyroiditis (HT) is largely unknown. However, genetic susceptibility is believed to play a major role. The lymphoid tyrosine phosphatase (LYP), encoded by the protein tyrosine phosphatase-22 (PTPN22) gene, is a powerful inhibitor of T cell activation. Recently, a single-nucleotide polymorphism (SNP), encoding a functional arginine to tryptophan residue change at PTPN22 codon 620 in Caucasians has been shown to be associated with GD and other autoimmune diseases. We have used a polymerase chain reaction (PCR)-restriction fragment (XcmI) assay to examine genotypes at the codon 620 polymorphism in 334 unrelated patients with AITD and 179 controls. None of the patients with AITD and controls had the tryptophan allele. These data suggest that the codon 620 polymorphism of the PTPN22 gene does not have a causal role for AITD in the Japanese. However, we cannot exclude the PTPN22 region as harboring another susceptibility locus for AITD in linkage disequilibrium with the Trp/Arg SNP.

Asian People↗

PubMed2005

Genetic susceptibility in thyroid autoimmunity.

The autoimmune thyroid diseases (AITD) include Graves' disease (GD) which manifests in hyperthyroidism and Hashimoto's thyroiditis (HT), manifesting as hypothyroidism. Genetic susceptibility in combination with external factors (e.g. dietary iodine) are believed to initiate the autoimmune response to thyroid antigens in AITD. Indeed, there is solid epidemiological data to support a strong genetic influence on the etiology of AITD including family and twin studies. Recently, there has been significant progress toward the identification of the AITD susceptibility genes. Several loci (genetic regions) that are linked with AITD have been mapped and in some of these loci putative AITD susceptibility genes have been identified. Some of these loci predispose to a single phenotype (GD or HT), while other loci are common to both diseases, indicating that there is a shared genetic susceptibility to GD and HT. The putative GD and HT susceptibility genes include both immune modifying genes (e.g. HLA, CTLA-4) and thyroid specific genes (e.g. TSHR, Tg) and it is likely that the final disease phenotype is a result of an interaction between these loci, as well as environmental influences.

Antigens, CD↗

PubMed2004

Interferon induced Autoimmune Thyroid Disease (AITD): a model for human autoimmunity.

Interferon (IFN) alpha treatment for various conditions has been associated with thyroid autoimmunity. The incidence of interferon induced thyroid autoimmunity has been reported to range from 2.5% to 42%, possibly depending upon dose and duration of medical therapy and patient characteristics. It is not known whether IFN-alpha initiates autoimmune thyroid disease (AITD) or simply exacerbates AITD in individuals with subclinical AITD.

Animals↗

PubMed2004

Analysis of HLA genes in families with autoimmune diabetes and thyroiditis.

Type 1 diabetes (T1D) and autoimmune thyroid disease (AITD) are the most common autoimmune endocrine disorders. The similar pathogenesis of T1D and AITD and their tendency to occur together suggest that their etiology may involve common genetic factors. We hypothesized that the human leukocyte antigen (HLA) locus may contribute in part to the joint susceptibility to T1D and AITD. We therefore analyzed a data set of 40 multiplex families in which T1D and AITD clustered ("T1D-AITD families") for linkage and association with the HLA class II locus. We found evidence for linkage of the HLA region to T1D (maximum logarithm of odds score [MLS] = 7.3), to Hashimoto thyroiditis (HT) (MLS = 1.5), and to both (MLS = 3.8). Transmission disequilibrium test analysis revealed significant association of both T1D and AITD with HLA-DR3; however, only T1D was associated with HLA-DR4. We concluded that the finding of evidence for linkage of HLA with HT is in contrast to the strong evidence against linkage found in previous studies of AITD-only families; therefore, it is possible that the AITD phenotype seen in T1D families has a different genetic etiology than the AITD phenotype in AITD-only families; that HLA-DR3 was the major HLA allele contributing to the joint genetic susceptibility to T1D and AITD, whereas other alleles (e.g., DR4) are phenotype specific; and that because the logarithm of odds score for T1D + HT was lower than for T1D alone, additional non-HLA loci must contribute to the shared genetic susceptibility to T1D and AITD.

Alleles↗

PubMed2004

Association of a thyroglobulin gene polymorphism with Hashimoto's thyroiditis in the Japanese population.

OBJECTIVE: The aetiology of the autoimmune thyroid diseases (AITDs), Graves' disease (GD) and Hashimoto's thyroiditis is largely unknown. However, genetic susceptibility is believed to play a major role. Two whole genome scans from Japan and from the USA identified a locus on chromosome 8q24 which showed evidence for linkage with AITD and HT. Recent studies have demonstrated an association between a Tg polymorphisms and AITD, suggesting that Tg is the susceptibility gene on 8q24. PATIENTS: We studied 308 Japanese AITD patients (194 GD and 114 HT patients) and 417 Japanese control subjects in association studies. DESIGN: Case-control association studies were performed using D8S284 and D8S272, microsatellite markers located in the 8q24 region, Tgms1 and Tgms2, microsatellite markers in introns 10 and 27, respectively, of Tg, and a SNP in exon 33 of Tg. RESULTS: No differences in allele frequencies were observed between AITD patients and controls for D8S284, D8S272 and Tgms1. Similarly, for Tgms2 and the exon 33 SNP no significant differences in allele frequency distribution were observed for all AITD patients. However, when analysing the HT patients alone we found a significant association between the 330 bp/352 bp genotype of Tgms2 and HT (HT = 16.7%, controls = 7.1%; corrected P-value = 0.01, OR = 2.6). CONCLUSION: Our results confirm the previous reports of an association between the Tg gene and AITD and suggest that Tg is an AITD susceptibility gene.

Alleles↗

PubMed2004

Analysis of immune regulatory genes in familial and sporadic Graves' disease.

Graves' disease (GD) is seen in apparently sporadic and familial forms. At least two immune regulatory genes are associated with GD, human leukocyte antigen (HLA) and cytotoxic T lymphocyte antigen-4 (CTLA-4). The aim of our study was to examine the contributions of HLA and CTLA-4 to the familial clustering of GD by analyzing them for association with familial and sporadic GD. We analyzed 160 Caucasian GD patients (69 familial and 91 sporadic), and 150 matched controls. Analysis of all GD patients demonstrated significant associations between GD and HLA-DR3 [P = 9.0 x 10(-7); relative risk (RR) = 3.8] and two CTLA-4 single nucleotide polymorphisms (SNPs), A/G(49) SNP (P = 0.03; RR = 1.5), and CT60 SNP (P = 0.03; RR = 1.4). Moreover, there was evidence for joint susceptibility to risk between HLA-DR3 and CTLA-4, giving a combined RR of 5.9. Subset analysis demonstrated no significant difference between the frequencies of HLA-DR3 and the susceptibility alleles of CTLA-4 A/G(49) and CT60 SNPs in the familial and sporadic GD subsets (P > 0.05). These results suggested that HLA-DR3 and CTLA-4 conferred a general increased risk for GD in both the sporadic and familial forms, and that the risk conferred by them was additive. However, HLA-DR3 and CTLA-4 did not have a stronger effect in the familial GD patients, suggesting that additional genes must contribute to the aggregation of GD within families.

Alleles↗

PubMed2003

Amino acid substitutions in the thyroglobulin gene are associated with susceptibility to human and murine autoimmune thyroid disease.

The 8q24 locus, which contains the thyroglobulin (Tg) gene, was previously shown to be strongly linked with autoimmune thyroid disease (AITD). We sequenced all 48 exons of the Tg gene and identified 14 single-nucleotide polymorphisms (SNPs). Case control association studies demonstrated that an exon 10-12 SNP cluster and an exon 33 SNP were significantly associated with AITD (P < 0.01). Haplotype analysis demonstrated that the combination of these two SNP groups was more significantly associated with AITD (P < 0.001). Gene-gene interaction studies provided evidence for an interaction between HLA-DR3 and the exon 33 SNP, giving an odds ratio of 6.1 for Graves' disease. We then sequenced exons 10,12, and 33 of the mouse Tg gene in 19 strains of mice. Fifty percent of the strains susceptible to thyroiditis had a unique SNP haplotype at exons 10 and 12, whereas none of the mouse strains that were resistant to thyroiditis had this SNP haplotype (P = 0.01). We concluded that Tg is a susceptibility gene for AITD, both in humans in and in mice. A combination of at least two Tg SNPs conferred susceptibility to human AITD. Moreover, the exon 33 SNP showed evidence for interaction with HLA-DR3 in conferring susceptibility to Graves' disease.

Alleles↗

PubMed2003

Common and unique susceptibility loci in Graves and Hashimoto diseases: results of whole-genome screening in a data set of 102 multiplex families.

The autoimmune thyroid diseases (AITDs), comprising Graves disease (GD) and Hashimoto thyroiditis (HT), develop as a result of a complex interaction between predisposing genes and environmental triggers. Previously, we identified six loci that showed evidence for linkage with AITD in a data set of 56 multiplex families. The goals of the present study were to replicate/reject the previously identified loci before fine mapping and sequencing the candidate genes in these regions. We performed a whole-genome linkage study in an expanded data set of 102 multiplex families with AITD (540 individuals), through use of 400 microsatellite markers. Seven loci showed evidence for linkage to AITD. Three loci, on chromosomes 6p, 8q, and 10q, showed evidence for linkage with both GD and HT (maximum multipoint heterogeneity LOD scores [HLOD] 2.0, 3.5, and 4.1, respectively). Three loci showed evidence for linkage with GD: on 7q (HLOD 2.3), 14q (HLOD 2.1), and 20q (LOD 3.3, in a subset of the families). One locus on 12q showed evidence of linkage with HT, giving an HLOD of 3.4. Comparison with the results obtained in the original data set showed that the 20q (GD-2) and 12q (HT-2) loci continued to show evidence for linkage in the expanded data set; the 6p and 14q loci were located within the same region as the previously identified 6p and 14q loci (AITD-1 and GD-1, respectively), but the Xq (GD-3) and 13q (HT-1) loci were not replicated in the expanded data set. These results demonstrated that multiple genes may predispose to GD and HT and that some may be common to both diseases and some are unique. The loci that continue to show evidence for linkage in the expanded data set represent serious candidate regions for gene identification.

Chromosome Mapping↗

PubMed2002

The influence of human leucocyte antigen (HLA) genes on autoimmune thyroid disease (AITD): results of studies in HLA-DR3 positive AITD families.

OBJECTIVE: Population-based, case-control studies have consistently shown association of Graves' disease (GD) with human leucocyte antigen (HLA)-DR3 in Caucasian populations. HLA association studies in Hashimoto's thyroiditis (HT) have also suggested an association with DR3, as well as with other HLA alleles. In contrast, HLA linkage studies in autoimmune thyroid disease (AITD) have been largely negative. The aim of the present study was to investigate the role of HLA in AITD and to explain the observed associations, but lack of linkage, by examining only AITD families with the associated allele, DR3. PATIENTS: We studied 99 probands (60 with GD and 39 with HT) from 99 multiplex, multigenerational Caucasian AITD families, and 135 age- and sex-matched Caucasian controls in association studies. In addition, a dataset of 34 Caucasian AITD families (out of the 99 families) with HLA-DR3 positive probands were analysed in linkage studies. DESIGN: HLA typing was performed using the technique of group-specific polymerase chain reaction-amplification with restriction enzyme digestion. Whole genome screening was performed using the ABI microsatellite panels. For fine mapping of the HLA region, we used the following markers: D6S276, D6S464, D6S439, D6S273, tumour necrosis factor alpha and D6S1610. LOD scores were calculated using the LIPED and GeneHunter programs. RESULTS: Case-control association analyses using the probands from our 99 Caucasian families showed an association of GD with DRB1*03 [P = 0.00032, relative risk (RR) = 3.4]. Linkage analysis for the HLA region in the 34 DR3 positive AITD families showed negative LOD scores throughout the region. The two-point LOD score at marker D6S273 (the closest to HLA-DRB1) was -3.0, and the multipoint LOD score was -7.6, demonstrating strong evidence against linkage to the HLA region in the subset of DR3 positive families. Whole genome screening in the subset of 34 DR3 positive families revealed one locus showing evidence for linkage to AITD: D3S1580 on chromosome 3q27 with a maximum two-point LOD score of 2.1. CONCLUSIONS: The HLA locus did not cosegregate with disease in DR3 positive families, suggesting that HLA genes are not major genes for AITD expression even within DR3 positive families; Hence, although HLA-DR3 was associated with GD in the probands, it was most likely a modulating gene and not causative; and, as the DR3 positive families showed evidence for linkage with D3S1580, it may imply that the DR3 gene modulated the effect of a susceptibility gene within the D3S1580 locus.

Case-Control Studies↗

PubMed2002

A germline single nucleotide polymorphism at the intracellular domain of the human thyrotropin receptor does not have a major effect on the development of Graves' disease.

Graves' disease (GD) is caused by an interplay of genetic factors and environmental triggers. The major antigen in GD is the thyrotropin receptor (TSHR) on the surface of the thyroid epithelial cell. Population-based case-control studies have largely shown no association of GD with the D36H (Asp to His) and P52T (Pro to Thr) single nucleotide polymorphisms (SNPs) in the N-terminal region of the extracellular domain of the TSHR gene in Caucasian populations. Recently, a D727E (Asp to Glu) SNP in the intracellular C-terminal domain of the TSHR was reported to be associated with GD in a Russian population. In the present study we assessed whether the codon 727 SNP is associated with GD in a Caucasian population. We found no significant differences in codon 727 SNP frequencies between GD patients and controls. In addition, our results did not show an effect of the SNP on the GD phenotype and on disease severity. Further analysis showed no evidence that the TSHR 727 SNP modulated the risk for GD conferred by HLA (DR3) and/or CTLA-4 (SNP 49 G allele) genes. A meta-analysis combining our data and those of 2 previous studies showed a very weak association between the D727E SNP and GD (p = 0.03, relative risk = 1.6). Therefore, we concluded that the TSHR gene is not a major gene for GD in our population.

Gene Expression↗

PubMed2002

Thyroglobulin is a thyroid specific gene for the familial autoimmune thyroid diseases.

The autoimmune thyroid diseases (AITDs) develop as a result of a complex interaction between predisposing genes and non-genetic factors. We have completed a whole genome scan in 56 families which revealed 7 major AITD loci (LOD scores >2), and additional minor loci (LOD scores >1). One of the minor loci was on chromosome 8q24 giving a maximum LOD score (MLS) of 1.8 at marker D8S284. This locus contained the thyroglobulin (Tg) gene which was a strong candidate gene for AITD. Because of this we analyzed the Tg gene region in detail using an expanded dataset of 102 families. The new linkage analysis showed stronger evidence for linkage at the Tg gene locus with an MLS of 3.5 between markers D8S514 and D8S284 (NPL = 2.0). We then proceeded to analyze the Tg gene directly. We identified a new microsatellite inside intron 27 of the Tg gene (designated Tgms2). Tgms2 showed strong evidence for linkage with AITD (MLS = 2.9), further suggesting that the Tg gene was linked to AITD. Association studies comparing 224 Caucasian AITD patients to 134 Caucasian controls showed an association of Tgms2 with AITD (p = 0.05, relative risk [RR] = 1.4). The association was stronger when only the probands from the linked families (n = 32) were used (p = 0.004, RR = 2.3). Transmission disequilibrium test (TDT) analysis also showed an association of Tgms2 with AITD (p = 0.02). We concluded therefore that the Tg gene was a major AITD susceptibility gene because it was both linked and associated with AITD.

Case-Control Studies↗