Biomedical subjects

Toshiro Hara

Publications and source records attributed to Toshiro Hara.

At least 73 records · Page 4Linked to original sources

PubMed2003

Tumour necrosis factor receptor-associated periodic syndrome with a novel mutation in the TNFRSF1A gene in a Japanese family.

UNLABELLED: Tumour necrosis factor receptor-associated periodic syndrome (TRAPS) is a dominantly inherited disorder characterised by recurrent episodes of sustained fever. Here we report a case of TRAPS with a novel TNFRSF1A mutation, C70S, in a Japanese family. The mutation disrupts one of the three disulphide bonds in cysteine-rich domain 2 of TNF receptor 1, similar to the reported mutations of the same cysteine residue (C70R, C70Y). This is the first confirmed case of TRAPS in an eastern Asian population. The patient's asymptomatic sister as well as their mother with mild symptoms had the same mutation. CONCLUSION: Although tumour necrosis factor receptor-associated periodic syndrome has been reported mainly in families of northern European ancestry, our case suggests the need to include it in the differential diagnosis of patients with recurrent fever even in ethnic groups in which no case has been documented.

Adolescent↗

PubMed2003

Female agammaglobulinemia due to the Bruton tyrosine kinase deficiency caused by extremely skewed X-chromosome inactivation.

We analyzed the cause of agammaglobulinemia in a girl whose father had been diagnosed as having X-linked agammaglobulinemia (XLA). Flow cytometric analysis revealed the lack of peripheral B cells with the block of B-cell differentiation in the stages between pro-B cells and pre-B cells in the bone marrow, and the defect of the Bruton tyrosine kinase (BTK) expression on monocytes. We found a BTK gene mutation in the first single base pair of intron 11 in her father and heterozygous mutation in the patient at the site. Sequence analysis of abnormally smaller-sized polymerase chain reaction (PCR) products of cDNA confirmed splicing abnormalities due to the mutation. Maternally derived X chromosome was exclusively inactivated in peripheral blood and oral mucosal cells. This is the first report of female XLA caused by heterozygous BTK gene abnormality and extreme nonrandom inactivation of X chromosome on which normal BTK gene is located.

Agammaglobulinaemia Tyrosine Kinase↗

PubMed2003

A functional polymorphism in the promoter/enhancer region of the FOXP3/Scurfin gene associated with type 1 diabetes.

FOXP3/Scurfin, a member of forkhead/winged-helix proteins, is involved in the regulation of T-cell activation, and essential for normal immune homeostasis. The FOXP3/Scurfin gene is located on chromosome Xp11.23, which includes one of the type 1 diabetes susceptible loci. Therefore, we investigated whether the human FOXP3/Scurfin gene might be a new candidate gene for type 1 diabetes. We first screened the human FOXP3/Scurfin gene for microsatellite and single nucleotide polymorphisms. Next, we performed an association study between the FOXP3/Scurfin gene and type 1 diabetes. Then, the evaluation of promoter/enhancer activity of the intron with (GT)(n) polymorphism was performed by dual luciferase reporter assay. We demonstrated two regions contained microsatellite polymorphisms; one was (GT)(n), located on intron zero and the other (TC)(n) on intron 5, which were under linkage-disequilibrium. The (GT)(15) allele showed a significantly higher frequency in patients with type 1 diabetes than in controls (43.1% vs 32.6%, P=0.0027). The genotype frequencies of (GT)(15)/(GT)(15) in female patients and of (GT)(15) in male patients tended to be higher than those in female ( P=0.064) and male ( P=0.061) controls, respectively. A significant difference in the enhancer activity between (GT)(15) and (GT)(16) dinucleotide repeats was detected. In conclusion, the FOXP3/Scurfin gene appears to confer a significant susceptibility to type 1 diabetes in the Japanese population.

DNA-Binding Proteins↗

PubMed2003

Association study between interleukin-12 receptor beta1/beta2 genes and type 1 diabetes or asthma in the Japanese population.

Interleukin-12 (IL-12) secreted from macrophages or dendritic cells plays an important role in the protection against intracellular pathogens as well as the developmental commitment of T helper 1 cells. IL-12 exerts its biological effects through binding to specific IL-12 receptors (IL-12Rs) termed IL-12Rbeta1 and IL 12Rbeta2. In this paper, we performed association studies between the three reported polymorphisms (Q214R, M365T and G378R) of the IL-12Rbeta1 gene or the newly identified polymorphisms (P238L, IVS9 -7G>A, IVS13 -121G>A, A643T, P779P and c.3283T>G) of the IL-12Rbeta2 gene, and the development of type 1 diabetes or atopic asthma as representative Th1- and Th2- dominant diseases, respectively. The association study of each polymorphism of the IL-12Rbeta1 or IL-12Rbeta2 gene and type 1 diabetes or asthma showed that these IL-12R genes did not contribute to the development of type 1 diabetes or asthma in the Japanese population. Further analysis in individuals with susceptibility to intracellular pathogens may elucidate the importance of the IL-12R genes.

Adolescent↗

PubMed2003

Founder effect of the C9 R95X mutation in Orientals.

A nonsense mutation at codon 95 (R95X) in the C9 gene is responsible for most Japanese C9 deficiency (C9D) cases, with a carrier frequency of 6.7%. Upon analysis of microsatellite markers and newly identified dinucleotide repeat number polymorphisms in the 3' flanking region of the C9 gene, a founder effect was demonstrated for the R95X mutation of the C9 gene in Japanese. Screening for the R95X mutation in Korean and Chinese individuals showed that the R95X carrier frequencies in Koreans and Chinese were 2.0% and 1.0%, respectively. Although homozygotes for the R95X mutation were not found in Korea or China, the shared haplotype of the dinucleotide repeat number polymorphisms appeared to be associated with the R95X mutation in the heterozygotes in Korea and China. The founder effect found in East Asians (Japanese, Koreans and Chinese) but not in Caucasians, as well as the haplotype sharing in only a small chromosomal interval, suggested that the R95X mutation of C9 gene was ancient and had occurred after the divergence of East Asians and Caucasians, and before migration of the Yayoi people to Japan. Since the mortality of meningococcal infections in complement-deficient patients is lower than that in normal individuals, a founder effect and a selective advantage in isolation might be the main reasons for the high frequency of the R95X mutation in Japan.

Alleles↗

PubMed2003

Dominant beta-thalassemia with hemoglobin Hradec Kralove: enhanced hemolysis in the spleen.

We describe a 6-year-old girl and her mother with dominant beta-thalassemia due to hemoglobin Hradec Kralove (Hb HK). Both patients presented microcytic anemia, jaundice, splenomegaly, cholelithiasis, and recurrent hemolytic bouts. Osmotic resistance tests using saline and coiled planet centrifugation revealed the increased fragility of the red cell membrane. On the other hand, the glycerol lysing time was prolonged, and results of the isopropanol test were weakly positive. Despite mimicking the features of hereditary spherocytosis, the results of the genetic analyses verified the second reported family with Hb HK (codon 115, GCC [Ala] --> GAC [Asp]). Splenectomy was effective for the amelioration of hemolysis. Of 7 reported patients with Hb variants at beta-globin codon 115 (Hb Madrid and Hb HK), 5 underwent splenectomy. Because of the variable augmentation of extramedullary hemolysis in dominant beta-thalassemias, genotyping is necessary for determining the clinical indication of splenectomy.

Adult↗

PubMed2003

Preferential expansion of Vgamma9-JgammaP/Vdelta2-Jdelta3 gammadelta T cells in nasal T-cell lymphoma and chronic active Epstein-Barr virus infection.

We recently established an Epstein-Barr virus (EBV)-positive gammadelta T-cell line from a nasal T/natural killer (NK)-cell lymphoma (Nagata H, Konno A, Kimura N, Zhang Y, Kimura M, Demachi A, Sekine T, Yamamoto K, Shimizu N: Characterization of novel natural killer (NK)-cell and gammadelta T-cell lines established from primary lesions of nasal T/NK-cell lymphomas associated with the Epstein-Barr virus. Blood 2001, 97:708-713). Subsequently, we established two novel EBV-positive gammadelta T-cell lines from the peripheral blood of patients with chronic active EBV infection. Analysis of the terminal repeat of EBV showed that the three cell lines consisted of monoclonal populations, and flow cytometry showed that they had a common phenotype of gammadelta T cells: CD3(+) CD4(-) CD8(-) CD16(-) CD19(-) CD56(+) CD57(-) HLA-DR(+) T-cell receptor (TCR) alphabeta(-) TCR gammadelta(+). Analysis for the expression of TCR by flow cytometry showed that all three cell lines were Vgamma9(+)/Vdelta2(+), but negative for VgammaI, Vdelta1, or Vdelta3 TCR. Southern blot analysis for TCR genes showed that the three cell lines had a common rearrangement of Vgamma9-JgammaP and Jdelta3 genes. Polymerase chain reaction and sequence analysis of the junction between Vdelta and Jdelta genes revealed that the Jdelta3 genes were rearranged with the Vdelta2 genes. In contrast, none of the EBV-negative gammadelta T-cell lines, Molt-14, Peer, or Loucy, which were analyzed for controls, had Vgamma9 or Vdelta2 TCR, or a rearrangement of Jdelta3 genes. These results indicated that Vgamma9-JgammaP/Vdelta2-Jdelta3(+) gammadelta T cells were preferentially affected by EBV and expanded in patients with nasal gammadelta T-cell lymphoma and chronic active EBV infection. Jdelta3(+) gammadelta T cells are known to be a very minor population in gammadelta T cells of peripheral blood, whereas Vgamma9-JgammaP/Vdelta2-Jdelta1(+) cells are the major population. The close association of EBV with this particular gammadelta T-cell population may provide a key to the etiology of EBV-positive lymphoproliferative diseases.

Antigens, CD↗

PubMed2003

Quantification of circulating varicella zoster virus-DNA for the early diagnosis of visceral varicella.

Varicella zoster virus (VZV)-DNA was quantified in peripheral blood of 2 patients with visceral varicella due to endogenous reactivation. An 18-year-old male contracted varicella following the courses of chemotherapy for T cell lymphoma. Another 18-year-old male suffered from varicella 16 months after the complete engraftment of hematopoietic stem cell transplantation. Both patients had past VZV infection, but no recent contact with the disease. Paralytic ileus and ascites preceded the skin lesions. Quantitative real-time polymerase chain reaction revealed >200 copies of VZV per 1 ml of whole blood before or at the time when cropping vesicles emerged. The viral load reflected their prolonged clinical courses. Similar levels of VZV-DNA were detected in primary varicella patients, but not in herpes zoster patients or immunocompromised children without varicella or zoster. Quantitative monitoring of circulating VZV-DNA may be useful for the diagnosis and assessing the treatment response of visceral varicella in immunocompromized hosts.

Adolescent↗

PubMed2003

The lipocalin 24p3, which is an essential molecule in IL-3 withdrawal-induced apoptosis, is not involved in the G-CSF withdrawal-induced apoptosis.

Many hematopoietic cells undergo apoptosis when deprived of specific cytokines. Lipocalin 24p3, reported to be induced in hematopoietic cells by interleukin 3 (IL-3) depletion, induces hematopoietic cell apoptosis despite the presence of IL-3. As granulocyte colony stimulating factor (G-CSF) depletion also induces the apoptosis of G-CSF-dependent cell line cells, we examined the effect of 24p3 on the apoptotic function induced by G-CSF depletion. 24p3 was induced by the depletion of IL-3, but not G-CSF, in cytokine-dependent cell lines. Although 24p3 suppressed growth induced by IL-3, it did not influence G-CSF-dependent cell growth. These observations show that 24p3 is not involved in the G-CSF withdrawal-induced apoptosis, although it is essential in IL-3 withdrawal-induced apoptosis.

Acute-Phase Proteins↗

PubMed2003

Cytokine imbalance in hyper-IgE syndrome: reduced expression of transforming growth factor beta and interferon gamma genes in circulating activated T cells.

Hyper-IgE syndrome (HIES) is a primary immunodeficiency disease characterized by recurrent infections and marked immunoglobulin (Ig)E elevation. To assess the proper T-cell defects of HIES, the cytokine profile of naturally activated T cells was compared between HIES, atopic dermatitis and chronic granulomatous disease (CGD). Intracellular flow cytometric analysis after in vitro stimulation showed no difference in the proportion of interferon (IFN)gamma- or interleukin 4 (IL-4)-producing T cells among these diseases. Quantitative polymerase chain reaction (PCR) for the cytokine genes was performed using circulating highly fractionated HLA-DR+ and HLA-DR- T cells. The IFNgamma/IL-4 or IFNgamma/IL-10 ratios were lower in HLA-DR+ T cells of HIES than in CGD (P = 0.0106, 0.0445), but did not differ between HIES and atopy. The transforming growth factor-beta (TGFbeta)/IL-4 ratio in HLA-DR+ T cells of HIES was lower than that of atopy (0.0106) or CGD (0.0062). The TGFbeta/IL-4 ratio in HLA-DR- T cells of HIES was also lower than that of atopy (0.0285). Stepwise logistic regression analysis identified TGFbeta/IL-4 ratios in HLA-DR+ (0.0001) or HLA-DR- (0.0086) T cells as the most powerful parameters to distinguish HIES from atopy and/or CGD. Serum IgE levels negatively correlated with IFNgamma/IL-4 (0.0108), IFNgamma/IL-10 (0.0254), or TGFbeta/IL-4 (0.0163) ratios in HLA-DR+, but not HLA-DR-, T cells. These results suggested that the in vivo activated T cells of HIES did not sufficiently express the IFNgamma and TGFbeta genes, which could affect IL-4-dependent IgE production. The reduced TGFbeta expression may involve the indigenous T-cell defects of HIES.

Adolescent↗

PubMed2003

Inducible and endothelial constitutive nitric oxide synthase gene polymorphisms in Kawasaki disease.

BACKGROUND: Nitric oxide (NO) is secreted by immune and vascular endothelial cells, and appears to play important roles in the pathophysiology of Kawasaki disease (KD). Thus, genetic variations in NO synthase (NOS) genes may be involved in the development of coronary artery lesions (CAL) in KD. METHODS: The present study investigated the association of endothelial constitutive NOS (ecNOS) and inducible NOS (iNOS) gene polymorphisms with the development of CAL in KD in a Japanese population. RESULTS: The genotype distributions of 27-bp tandem repeat polymorphism within intron 4 of ecNOS gene did not show any significant difference between controls and KD patients with or without CAL. In addition, there was no significant association between whole-allele distribution of iNOS gene promoter (penta-repeat CCTTT) polymorphism and KD with or without CAL. CONCLUSION: These results did not support any association of ecNOS and iNOS gene polymorphisms to the development of CAL in KD patients in a Japanese population.

Asian People↗

PubMed2003

Reversible posterior leukoencephalopathy syndrome in children with cancers.

We report three cases of reversible posterior leukoencephalopathy syndrome (RPLS) in children with cancers. All patients presented with sudden confusional state, visual disturbance, and transient mild hypertension under the treatment of childhood cancers. Magnetic resonance imaging of the brain demonstrated cortical and subcortical lesions predominantly in the occipital region, which showed high intensity signal on fluid-attenuated inversion recovery images. All patients completely recovered from their neuropsychologic deficits only with antihypertensive therapy or discontinuation of the possible offending drugs. Early recognition of RPLS as a complication during cancer therapy in childhood may facilitate precise diagnosis and appropriate treatment.

Antineoplastic Agents↗

PubMed2003

A rapid speech synthesizing software on a PDA for Japanese with speech impairments.

We developed a Japanese-language, rapid synthesizing software application for use on a personal digital assistant. It has an unrestricted vocabulary and can synthesize words and sentences within 3 s. Eight hundred common sentences and words are preregistered. By touching the first character at the head of a preregistered sentence or word from an on-screen Kana (Japanese alphabet) chart, the user can select the sentence or word to be spoken. Characters on the Kana chart can also be input sequentially. Two Japanese subjects with speech impairments rated the device highly for its portability and quick response. Whereas communication previously had to be done by writing or sign language, it was easy for listeners with or without specialized training in communication with persons with speech impairments to understand the output from this device, making conversation easier which, in turn, improved the quality of life and social activity of these persons with speech impairments.

Asian People↗

PubMed2002

Association study of the NRAMP1 gene promoter polymorphism and early-onset type 1 diabetes.

Natural resistance-associated macrophage protein 1 (NRAMP1) has an important role in regulating macrophage functions that affect innate resistance as well as immune responses. We analyzed the microsatellite polymorphism in the promoter region of the human NRAMP1 gene in 206 type 1 diabetes patients and 200 normal children to determine whether this polymorphism might be associated with type 1 diabetes in the Japanese population. The frequency of allele 2 (180 bp) of the promoter microsatellite polymorphism of the NRAMP1gene was slightly lower in the early-onset population (2-10 years of age) of type 1 diabetes patients than in controls, although the difference did not reach statistical significance. The association study of the cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) gene, located near the NRAMP1 gene, and type 1 diabetes showed that the CTLA-4 gene significantly contributed to the development of type 1 diabetes, whereas NRAMP1 had an additional effect on the onset of type 1 diabetes in the young population.

Abatacept↗

PubMed2002

Genetic basis of patients with bacille Calmette-Guérin osteomyelitis in Japan: identification of dominant partial interferon-gamma receptor 1 deficiency as a predominant type.

Interferon (IFN)-gamma-mediated immunity plays an important role in host defense against intracellular pathogens, especially mycobacteria. Six Japanese children with bacille Calmette-Guérin (BCG) osteomyelitis were evaluated (1 disseminated, 3 multiple, and 2 solitary types) for mutations of genes involved in interleukin-12-dependent, IFN-gamma-mediated immunity. Heterozygous small deletions with frameshift (818del4 and 811del4) that are consistent with the diagnosis of partial dominant IFN-gamma receptor 1 (IFN-gammaR1) deficiency were detected in 3 unrelated patients. Expression of IFN-gammaR1 on monocytes was significantly increased in all 3 patients. Screening of family members with recurrent and disseminated mycobacterial infections found the identical deletion in 1 of the fathers. Antimycobacterial treatment was effective in these patients and resulted in good clinical outcome. This study demonstrated that partial dominant IFN-gammaR1 deficiency was the most common in Japanese patients who showed predisposition to curable BCG osteomyelitis.

Adult↗

PubMed2002

Contribution of the interleukin 4 gene to susceptibility to subacute sclerosing panencephalitis.

BACKGROUND: Although the exact pathogenesis of subacute sclerosing panencephalitis (SSPE) remains to be determined, both viral and host factors seem to be involved. OBJECTIVE: To identify host genetic factors involved in the development of SSPE. METHODS: We investigated the association of polymorphisms in the T helper (Th)1 and Th2 cytokine, and related genes (interferon [IFN]-gamma, IFN-gamma receptor 1 [IFN-gamma R1], IFN-gammaR2 [IRF-1], interleukin 12 receptor beta 1 [IL-12Rbeta1], IL-4, IL-4R, and IL-10 genes) with SSPE in Japanese subjects. RESULTS: A significant association (P =.03) was observed between SSPE and the T allele of the biallelic polymorphism at position -589 in the promoter region of the IL-4 gene. The IRF-1 allele 1 tended to interact with the IL-4 promoter -589 T genotype in the development of SSPE (P =.06), as judged on logistic regression analysis. The frequency of the genotype combination of IL-4 promoter -589 T and IRF-1 allele 1 (at least 1 allele) in patients with SSPE was much higher than that in the controls (47.7% vs 22.0%; P =.003, chi2 analysis). However, there was no association between other polymorphisms and SSPE. CONCLUSION: To our knowledge, this study is the first to demonstrate the possibility that the IL-4 promoter gene -589 T gene polymorphism with increased IL-4 synthesis in combination with IRF-1 allele 1 confers host genetic susceptibility to SSPE in Japanese subjects.

Adolescent↗

PubMed2002

CD4-CD8- T-cell polymyositis in a patient with chronic active Epstein-Barr virus infection.

We describe a 17-year-old woman with chronic active Epstein-Barr virus infection (CAEBV), who developed EBV+CD4-CD8- T-cell polymyositis. At 14 years of age, CAEBV was diagnosed with fever, cytopenia, liver dysfunction, and hepatosplenomegaly. Despite the transient remission of interferon-alpha therapy, migratory lesions emerged in back and extremities. MRI indicated polymyositis. Biopsy specimens revealed intramuscular infiltration of CD3+, CD4-, CD8-, CD56-, and EBV-encoded RNA 1+ cells. Circulating CD4-CD8-Vdelta2/Vgamma9 cells increased. gammadeltaT-cells contained 20-200 times higher EBV-DNA (2 x 10(4) copies/microgDNA) than alphabetaT-cells or NK-cells. The ominous polymyositis might denote the musculotropic invasion of EBV+gammadeltaT-cell lymphoproliferative disease as a consequence of CAEBV.

Adolescent↗

PubMed2002

Five novel SLC7A7 variants and y+L gene-expression pattern in cultured lymphoblasts from Japanese patients with lysinuric protein intolerance.

Two distinct human light subunits of the heteromeric amino acid transporter, y+LAT-1 coded by SLC7A7 and y+LAT-2 coded by SLC7A6, are both known to induce transport system y+L activity. SLC7A7 has already been identified as the gene responsible for lysinuric protein intolerance (LPI). We successfully identified five novel SLC7A7 variants (S238F, S489P, 1630delC, 1673delG, and IVS3-IVS5del9.7kb) in Japanese patients with LPI by PCR amplification and direct DNA sequencing. In addition, we performed a semi-quantitative expression analysis of SLC7A7 and SLC7A6 in human tissue. In normal tissue, the gene-expression ratio of SLC7A6 to SLC7A7 was high in the brain, muscle, and cultured skin fibroblasts; low in the kidneys and small intestine; and at an intermediate level in peripheral blood leukocytes, the lungs, and cultured lymphoblasts. The gene-expression ratio of SLC7A6 to SLC7A7 in cultured lymphoblasts was significantly different between normal subjects and LPI patients with R410X and/or S238F, where the relative amount of SLC7A7 mRNA was significantly lower and the relative amount of SLC7A6 mRNA was statistically higher in affected lymphoblasts than in normal cells. Expression of SLC7A7 and SLC7A6 may thus be interrelated in cultured lymphoblasts.

Adolescent↗