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Hirokatsu Yanagihori

Publications and source records attributed to Hirokatsu Yanagihori.

7 recordsLinked to original sources
PubMed2006

Role of IL-12B promoter polymorphism in Adamantiades-Behcet's disease susceptibility: An involvement of Th1 immunoreactivity against Streptococcus Sanguinis antigen.

Adamantiades-Behcet's disease (ABD) is a chronic inflammatory multisystem disorder. Although the precise etiology is unclear, high prevalence of human leukocyte antigen (HLA)-B51 predisposition and predominantly involved T-helper type 1 cells (Th1)-type proinflammatory cytokines and extrinsic Streptococcal infection suggest a substantial association with an immunogenetic basis and strengthens the hypothesis that IL-12, a potent inducer of Th-1 immune reaction, is a putative candidate in its pathogenesis. These clinicopathological findings led us to examine interleukin 12 p40 (IL-12B) promoter polymorphism, for which the 4-base pair (bp) heterozygous insertion has been shown to affect the gene transcription and subsequent protein production. We analyzed IL-12B promoter genotypes in 194 Japanese subjects (92 with ABD and 102 normal controls) by PCR-based restriction enzyme digestion. The frequency of the insertion heterozygosity was significantly higher in patients than in controls (49/92, 53.3% vs 39/102, 38.2%, respectively). Comparing these with HLA haplotype data, this trend was more significant in HLA-B51-negative patients (29/42, 69.0% vs 20/50, 40.0%; P = 0.005). As assessed by semiquantitative reverse transcription-PCR and ELISA, stimulation with Streptococcal antigens specifically increased expression of IL-12 p40 mRNA and protein, in conjunction with IL-12 p70 induction, in peripheral blood mononuclear cells from heterozygous patients. Our results provide evidence for anti-bacterial host response toward Th1-immunity mediated by IL-12 in patients with ABD, and the possible insight into the genetic susceptibility that is independent of HLA background.

Adult↗
PubMed2005

c-kit Mutations in patients with childhood-onset mastocytosis and genotype-phenotype correlation.

Mastocytosis represents a clonal proliferation of mast cell hematopoietic progenitors caused by gain-of-function mutations of the c-kit gene. The heterogeneity of c-kit mutations may have contributed to difficulties in characterizing genotype-phenotype correlation of the disease. Our goal was to analyze a set of reported pathogenic c-kit mutations in patients with childhood-onset cutaneous mastocytosis, in comparison with those with adult-onset disease, and to correlate these with clinical presentation. We performed polymerase chain reaction and direct sequencing using genomic DNA samples from 16 nonfamilial Japanese patients with indolent cutaneous mastocytosis (12 with childhood-onset disease and 4 with adult-onset disease) to look for the most common c-kit mutations at codons 816, 560, 820, and 839. A substantial number of patients had missense codon 816 mutations (10 of 12 in the childhood-onset group, 83.3%; and 4 of 4 in the adult-onset group, 100%). The most common mutation was Asp816Val (9 of 16, 64.3%) followed by Asp816Phe (5 of 16, 35.7%). Moreover, children with the Asp816Phe mutation developed cutaneous mastocytosis at an earlier age as compared to those with the Asp816Val mutation (mean age of onset, 1.3 months versus 5.9 months, respectively; P = 0.068). No other mutation variations were found in our cohort. In summary, we confirmed a high incidence of two distinct c-kit mutations, Asp816Val and Asp816Phe, in patients with childhood-onset cutaneous mastocytosis. Our results provide new insights into common c-kit mutations, which may contribute to different clinical courses of the disease.

Adolescent↗
PubMed2003

Detection of herpes virus genomes in skin lesions from patients with Behçet's disease and other related inflammatory diseases.

Although the aetiology of Behçet's disease is still poorly understood, viral infection has long been postulated as one of the factors. To investigate the relationship between herpes viruses and Behçet's disease, we used polymerase chain reaction to detect herpes simplex virus 1 (HSV-1) and 2 (HSV-2), and human herpes virus 6 (HHV-6) and 7 (HHV-7) DNA in samples of lesional tissues from patients with Behçet's disease and other related inflammatory disorders. Four cases were positive for HSV-1; 1 of 11 Behçet's disease cases, 2 of 3 Sweet's disease cases and 1 of 3 erythema nodosum cases. Two cases were positive for both HSV-1 and HSV-2; one Behçet's disease and one erythema nodosum. All cases were negative for HHV-6 and HHV-7. These findings indicate that there might be some relationship between Behçet's disease and the presence of HSV-1 and/or HSV-2 DNA and that HHV-6 and HHV-7 do not seem to be involved in the pathogenesis of Behçet's disease. However, HSV-1 and HSV-2 DNAs were also detected in non-Behçet's disease lesions, suggesting that HSV-1/2 is not correlated to the direct pathogenesis of Behçet's disease.

Adult↗
PubMed2003

A case of intravascular large B-cell lymphoma with multiple organ involvement.

Intravascular large B-cell lymphoma (IVL) is a rare systemic disease characterized by clonal proliferation of neoplastic lymphoid cells within the capillary lumina of small blood vessels. The most common sites of involvement are cerebrovascular or sinusoid areas, resulting in a wide variety of neurologic deficits. Herein we describe a case of IVL that presented with multiple internal and external organ involvements, including the skin, bilateral kidneys, and lung, and with an aggressive clinical course. The confirmative diagnosis was based on the microscopic findings of the skin lesion with a B-cell immunophenotype. The patient suffered from repeated severe dyspnea, hypoxemia, and high-grade fever with a simultaneous increase in serum lactate dehydrogenase and soluble IL-2 receptor levels. These manifestations responded dramatically to intravenous injection of corticosteroid (500 mg/day for 3 days). Despite various clinical presentations, no neurological abnormality was observed until the patient died 12 months after the initial combination chemotherapy.

Diagnosis, Differential↗