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Nagoya-shi, Japan

Kunishima S.,Clinical Research Center | Saito H.,Nagoya Central Hospital
Current Opinion in Hematology | Year: 2010

Purpose of review: MYH9 disorders are autosomal dominant macrothrombocytopenias with leukocyte inclusion bodies caused by mutations in MYH9, the gene for the nonmuscle myosin heavy chain IIA. May-Hegglin anomaly and Sebastian, Fechtner, and Epstein syndromes belong to MYH9 disorders. The present review summarizes the recent advances in genetic diagnosis and our understanding of the pathogenetic mechanisms of MYH9 mutations and the development of nonhematological complications. Recent findings: A genotype-phenotype cohort study showed that patients with an MYH9 mutation in the motor head domain of myosin IIA have severe macrothrombocytopenia and are at a high risk for the development of glomerulonephritis and deafness. Among these, Arg702 mutations are associated with the most severe phenotype. In-vitro studies on cultured megakaryocytes elucidated that myosin IIA inhibits proplatelet formation. The loss of myosin IIA function owing to MYH9 mutations promotes proplatelet formation and may trigger precocious and premature platelet release, resulting in macrothrombocytopenia. Giant platelets only residually express mutant myosin IIA that has a loss of function and cannot participate in the reorganization of cytoskeletal contractile structures. Renal histopathological and immunochemical studies have suggested that glomerulonephritis in MYH9 disorders is caused by podocyte malfunction owing to defects in the myosin IIA structure and MYH9 expression. Summary: MYH9 disorders are not merely benign hematological abnormalities, but serious syndromic disorders affecting the kidney, inner ear, and lens. A genetic diagnosis is mandatory for an accurate prognosis of nonhematological complications and management or possibly prophylactic treatment. © 2010 Wolters Kluwer Health | Lippincott Williams & Wilkins.

Yamada S.,Nagoya University | Fujii T.,Nagoya University | Shimoyama Y.,Nagoya University | Kanda M.,Nagoya University | And 7 more authors.
Annals of Surgical Oncology | Year: 2014

Purpose: Morphological subtypes of intraductal papillary mucinous neoplasm (IPMN) have been established. Invasive IPMNs include colloid carcinoma and tubular carcinoma. Few studies have explored the association between the morphological and invasive subtypes in a large population. Clinical relevance of the morphological subtypes remains unclear. Methods: One hundred sixty-nine consecutive patients who underwent curative resection of IPMN were enrolled. The intraductal components were classified into four distinct epithelial subtypes: gastric, intestinal, pancreatobiliary, and oncocytic. The invasive components were classified as colloid or tubular. Results: The numbers of patients with gastric, intestinal, pancreatobiliary, and oncocytic subtypes were 123, 42, 3, and 1, respectively. Fifty-six patients had invasive cancer (tubular type, 42; colloid type, 14). The proportions of gastric type IPMN within each histological grade were 88 % among adenomas, 43 % among noninvasive carcinomas, 41 % among minimally invasive carcinomas, and 74 % among invasive carcinomas. Gastric subtype was more commonly associated with branch duct type and intestinal subtype with main duct type, and these tendencies were statistically significant (P = 0.0131). Furthermore, there was a strong correlation between gastric and tubular types and between intestinal and colloid types (P < 0.0001). The 5-year survival rate among the 56 invasive cancers was 52.7 % for gastric type and 89.7 % for intestinal type, which was statistically significant (P = 0.030). Conclusions: Gastric type IPMN is mostly derived from branch duct IPMN and often demonstrates benign behavior, as seen with adenomas. However, once gastric type IPMN develops into invasive carcinoma, the survival rate is significantly lower than other types. © 2014 Society of Surgical Oncology.

Suzuki A.,Nagoya University | Sanda N.,Nagoya University | Miyawaki Y.,Nagoya University | Fujimori Y.,Nagoya University | And 5 more authors.
Journal of Biological Chemistry | Year: 2010

Pregnant women show a low level of protein S (PS) in plasma, which is known to be a risk for deep venous thrombosis. 17β-Estradiol (E2), an estrogen that increases in concentration in the late stages of pregnancy, regulates the expression of various genes via the estrogen receptor (ER). Here, we investigated the molecular mechanisms behind the reduction in PS levels caused by E2 in HepG2-ERα cells, which stably express ERα, and also the genomic ER signaling pathway, which modulates the ligand-dependent repression of the PSα gene (PROS1). We observed that E2 repressed the production of mRNA and antigen of PS. A luciferase reporter assay revealed that E2 down-regulated PROS1 promoter activity and that this E2-dependent repression disappeared upon the deletion or mutation of two adjacent GC-rich motifs in the promoter. An electrophoretic mobility shift assay andDNApulldown assay revealed that the GC-rich motifs were associated with Sp1, Sp3, and ERα. In a chromatin immunoprecipitation assay, we found ERα-Sp protein-promoter interaction involved in the E2-dependent repression of PROS1 transcription. Furthermore, we demonstrated that E2 treatment recruited RIP140 and the NCoR-SMRT-HDAC3 complex to the PROS1 promoter, which hypoacetylated chromatin. Taken together, this suggested that E2 might repress PROS1 transcription depending upon ERα-Sp1 recruiting transcriptional repressors in HepG2-ERα cells and, consequently, that high levels of E2 leading to reduced levels of plasma PS would be a risk for deep venous thrombosis in pregnant women. © 2010 by The American Society for Biochemistry and Molecular Biology, Inc.

Yamada S.,Nagoya University | Fujii T.,Nagoya University | Sugimoto H.,Nagoya University | Nomoto S.,Nagoya University | And 3 more authors.
Pancreas | Year: 2013

OBJECTIVES: The objective of this study was to evaluate the relevance of defining borderline resectable (BR) pancreatic cancer as a distinct entity in the treatment scheme of pancreatic cancer as proposed by the National Comprehensive Cancer Network. METHODS: Among 375 patients with pancreatic cancer, 137 patients were deemed to have resectable disease (R) by preoperative imaging studies, whereas 96 were found to have an unresectable disease during surgery. The remaining 142 patients fulfilled the definition of BR and were further classified into 3 subgroups based on the National Comprehensive Cancer Network guidelines: portal vein invasion (PV[+]), common hepatic artery invasion (CHA[+]), and superior mesenteric artery invasion (SMA[+]). PV(+) was subdivided into types B, C, and D according to the degree of portal vein invasion. RESULTS: Patients in the R group had significantly better survival than those in the PV(+) group (P = 0.0038), who in turn survived significantly longer than those classified as SMA(+) (P = 0.041). Type B patients survived significantly longer than did types C and D patients (P = 0.013 and P = 0.030, respectively). In PV(+) patients, compliance with postoperative chemotherapy at 3 and 6 months was 56.9% and 44.6%, respectively, substantially inferior to patients with resectable disease (72.6% and 54.7%, respectively). CONCLUSIONS: The optimal treatment strategy may differ among various subgroups within the BR category. Copyright © 2013 by Lippincott Williams &Wilkins.

The way by which contact of blood with foreign surface accelerates clotting has been elucidated from the discovery of four rare disorders of blood coagulation; Hageman trait, plasma thromboplastin antecedent (PTA) deficiency, Fletcher trait, and Fitzgerald trait. Interestingly, it was unexpectedly found that Fletcher factor is plasma prekallikrein and Fitzgerald factor is high-molecular-weight kininogen; components of the kinin-generating system, thus disclosing intimate relationships among clotting, fibrinolysis and kinin generation which may be viewed as body's defense reactions against injury. This review mainly reflects our research on Fletcher trait and Fitzgerald trait during the 1970s in Cleveland. © Schattauer 2010.

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