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Tomoko Inagaki

Publications and source records attributed to Tomoko Inagaki.

13 recordsLinked to original sources
PubMed2006

Relationship between the diversity of the cagA gene of Helicobacter pylori and gastric cancer in Okinawa, Japan.

BACKGROUND: Helicobacter pylori CagA protein is considered to be one of the virulence factors associated with gastric cancer. CagA is injected into gastric epithelial cells, undergoes tyrosine phosphorylation, and binds to Src homology 2 domain-containing protein-tyrosine phosphatase (SHP-2). Two major subtypes of CagA have been observed in the SHP-2-binding site, the Western and East Asian types. The East Asian-type CagA binds to SHP-2 more strongly than the Western-type CagA. The diversity of CagA, which collectively determines the binding affinity of CagA to SHP-2, may be an important variable in determining the clinical outcome of infection by different H. pylori strains. METHODS: We investigated the relationship between the diversity of CagA and clinical outcome in Okinawa, Japan. A total 24 strains, 13 gastric cancer strains and 11 duodenal ulcer strains, were studied. We sequenced full-length cagA genes and analyzed the phylogenetic relationships between Okinawa isolates and previously characterized Western H. pylori strains. RESULTS: All isolates examined were cagA positive. The prevalence of East Asian CagA-positive strains was significantly higher in patients with gastric cancer (84.6%) than in patients with duodenal ulcer (27.3%) (chi-squared = 8.06, P = 0.011). The phylogenetic analysis showed that all gastric cancer strains with East Asian-type CagA were in the East Asian cluster, and that most duodenal ulcer strains were in the Western cluster. CONCLUSIONS: The origins of H. pylori isolates are different between gastric cancer strains and duodenal ulcer strains, and East Asian CagA-positive H. pylori infection is associated with gastric cancer. The strain diversity observed in Okinawa may affect the difference in the prevalence of disease associated with H. pylori infection in Japan.

Adult↗
PubMed2005

Intraductal tubular neoplasms of the pancreas: histogenesis and differentiation.

OBJECTIVES: Intraductal neoplasms of the pancreas are generally referred to as intraductal papillary mucin-producing neoplasms (IPMNs), according to the WHO classification system. Herein, we report that morphologic and immunohistochemical features of intraductal tubular carcinoma (ITC) are quite different from those of intraductal papillary mucinous carcinoma (IPMC). METHODS: We analyzed histogenesis and differentiation of ITC by light microscopy and immunohistochemistry. RESULTS: Histologically, ITC was characterized as an intraductal nodular appearances with a monotonous tubular growth pattern without papillary projection. ITC showed de novo-like appearance without sequential progression usually observed in IPMC, suggesting that ITC is a homogeneous neoplasm. Cuboidal tumor cells in ITC resembled normal pancreatic duct epithelia, and the characteristic growth pattern of ITC replaced that of normal pancreatic duct epithelium. Immunohistochemically, ITC cells were positive for MUC-1 on the apical side of the cell membrane. In contrast to ITC cells, IPMC cells were negative for MUC-1, and ductal adenocarcinoma cells were strongly positive for MUC-1, as was the stroma around the cancer. The immunohistochemical staining pattern of DUPAN-2 resembled that of MUC-1. Interestingly, localization of MUC-1 and DUPAN-2 staining in ITC cells was similar to that in normal pancreatic ductules. ITC cells were negative for MUC-2 and MUC-5AC. In contrast, most IPMC cells were positive for MUC-2 and MUC-5AC. CONCLUSION: Based on our histologic and immunohistochemical findings, the intraductal pancreatic neoplasm (IPN) can be classified into 2 groups: IPN with gastrointestinal differentiation and IPN with pancreatic duct differentiation. Our present data indicated that ITC cells may arise directly from duct epithelia without progression and possessed pancreatic duct differentiation. On the basis of our data, we suggest that classification of pancreatic neoplasms in the WHO and The Armed Forces Institute of Pathology (AFIP) systems should be reconsidered.

Adenocarcinoma↗
PubMed2004

Mucinous cystadenoma of the pancreas 17 years after excision of gallbladder because of a choledochal cyst.

A 56-year-old woman who had undergone excision of the gallbladder because of a choledochal cyst had a tumorous lesion of the pancreas identified by upper abdominal ultrasonography, but an operation was not carried out, because there was no apparent increase in the cystic mass and no elevation of serum tumor markers. In October 2001, she was admitted to our hospital to check for malignancy because of elevated levels of the tumor marker Dupan-2. Abdominal enhanced computed tomography and upper abdominal ultrasonography revealed a large multilocular cystic mass in the body to tail of the pancreas. Endoscopic retrograde cholangiopancreatography showed elongation of the common duct that communicates with the common bile duct and the main pancreatic duct, indicating an anomalous arrangement of the biliary and pancreatic duct system. No apparent communications between the cystic mass and the main pancreatic duct were observed. In January 2002, the patient underwent a spleen-preserving distal pancreatectomy, and histopathological and immunohistochemical examinations led to the diagnosis of pancreatic mucinous cystadenoma with ovarian-like stroma. The mucinous cystadenoma was detected 17 years after the operation for the choledochal cyst. To the best of our knowledge, no documented case reports of mucinous cystadenoma of the pancreas associated with a choledocal cyst have been reported to date. We present here the first case report of pancreatic mucinous cystadenoma occurring in the body to tail of the pancreas, associated with a choledocal cyst.

Cholangiopancreatography, Endoscopic Retrograde↗
PubMed2004

Fulminant varicella infection complicated with acute respiratory distress syndrome, and disseminated intravascular coagulation in an immunocompetent young adult.

Primary varicella infection in immunocompetent adults is very rare, but it has a high mortality rate because of serious complications. We describe a case of varicella infection in a previously healthy young adult complicated with acute respiratory distress syndrome (ARDS), rhabdomyolysis, acute hepatitis and disseminated intravascular coagulation (DIC). Acyclovir was administered for varicella infection and the ARDS was successfully treated with steroidpulse therapy, hemofiltration and a mechanical respiratory support with a positive end-expiratory pressure. Early administration of antiviral agents and extensive management were thought to be necessary for such patients with severe complications.

Adult↗
PubMed2003

Immunohistochemical evaluation of tissue-specific proteolytic enzymes in adenomas containing foci of early carcinoma: correlations with cathepsin D expression and other malignant features.

BACKGROUND: Cathepsin D (CD) is an aspartyl lysosomal protease, and the prognostic value of CD expression has been studied in a variety of tumors, however, its role in early adenocarcinomas remains unclear. AIM OF THE STUDY: We evaluated the expression of CD in a series of colorectal adenomas with severe dysplasia containing foci of early carcinoma and compared the results to several histopathological and immunohistochemical features. METHODS: Adenomas were obtained by endoscopic polypectomy from 33 patients. Twenty-four of the 33 adenomas contained well-differentiated adenocarcinomas and nine adenomas contained moderately differentiated adenocarcinomas. RESULTS: Positive CD expressions were observed in 25% of well-differentiated adenocarcinomas and in 66.7% of moderately differentiated adenocarcinomas (p < 0.05). Of the 12 adenocarcinomas with positive CD expression, four had positive CD expression in their adenomas (p < 0.01), 6 showed positive Ki-67 expression in their adenomas (NS), and 10 had positive p53 expression in their adenomas (p < 0.05). No significant association was seen between the level of CD expression and adenoma size. CONCLUSIONS: The expression of CD in adenocarcinoma correlated significantly with differentiation, and with the levels of CD and p53 expression in the adenomas of the polyp.

Adenocarcinoma↗
PubMed2002

Muscle MRI findings of HTLV-1-associated myelopathy.

We report here the muscle MRI findings in two patients with human T-cell lymphotropic virus type I-associated myelopathy (HAM). It is known that thigh muscles are vulnerable in HAM patients, but detailed information about the affected muscles has not been available. Muscle MRI findings of these patients showed that thigh muscles, especially adductor magnus, and semimembranosus muscles were severely affected, but lower leg muscles were comparatively preserved. In these affected muscles, neurogenic changes were observed by EMG. We concluded that muscle MRI is very useful to estimate the affected muscles in HAM patients.

Aged↗
PubMed2002

Podocyte injury promotes progressive nephropathy in zucker diabetic fatty rats.

The zucker diabetic fatty (ZDF-fa/fa) rat is one of the attractive models for type II diabetes based on impaired glucose tolerance caused by the inherited insulin-resistance gene fa. Characterization of nephropathy in this model may provide useful insights into the mechanism of the progression of diabetic nephropathy. The present study analyzed the pathophysiology of diabetes and nephropathy, including the process of glomerulosclerosis in this model by biochemical and morphometric analyses. In addition, we conducted studies in podocytes in culture to examine the direct effects of high glucose on podocytes. ZDF-fa/fa rats showed overt diabetes despite hyperinsulinemia as early as 3 months of age. Blood glucose levels increased further with a considerable decrease of insulin levels at 5 months. Glomerular filtration rate (GFR) was significantly elevated until 3 months, but fell to the level seen in lean rats by 7 months. Proteinuria started to rise during the period of increased GFR, and increased further after GFR had fallen to within the normal range. Renal fibronectin, collagen iv, and vascular endothelial growth factor mRNA levels were increased at 7 months. Glomerulosclerosis commenced as early as 5 months of age, and was associated with glomerular hypertrophy and mild mesangial expansion with evidence of accentuated podocyte injury, as revealed by increased expression of desmin. Electron microscopy suggested that degeneration of podocytes and the development of tuft adhesions were responsible for the glomerular sclerosis in this model. In addition, glomeruli from the diabetic rats showed up-regulation of the cyclin kinase inhibitors, p21 and p27. Further studies suggested that the increase in p27 expression was predominantly caused by podocytes, because predominant immunolocalization of p27 in podocytes in diabetic rats and high glucose medium induced cell hypertrophy accompanied by p27 up-regulation in differentiated podocyte cell lines. In conclusion, progressive diabetic nephropathy in ZDF-fa/fa rats is associated with evidence of podocyte injury. High concentrations of ambient glucose induced podocyte hypertrophy and stress in vitro, suggesting that the podocyte is a likely target of the diabetic milieu.

Aging↗
PubMedDate not supplied

Cyopathologic and histologic features of biphasic pulmonary blastoma: a case report.

BACKGROUND: Biphasic pulmonary blastoma is a rare malignant neoplasm of debatable histogenesis. Although well described histologically, it is scarcely mentioned in the cytologic literature. CASE: A 78-year-old man reporting intermittent hemoptysis was admitted to the hospital. Chest radiography revealed a right-sided pulmonary mass. Cytologic examination of tumor specimens revealed 2 types of malignant cells. The smears were highly cellular, with a necrotic background. The stromal cells had predominantly round to ovoid or spindle-shaped nuclei and scant cytoplasm, and the nucleoli had slightly irregular borders with coarsely aggregated chromatin. The epithelial cells were arranged in sheets and glandular configurations. The cytoplasm of these cells was finely vacuolated or foamy, with indistinct cellular boundaries; eccentrically located nuclei were hyperchromatic and had irregularly shaped nucleoli. The cell block preparation showed a distinctly biphasic malignant tumor with the classic morphologic features of pulmonary blastoma. CONCLUSION: A preoperative diagnosis ofpulmonary blastoma is difficult to obtain by cytopathologic methods. A diagnosis of biphasic pulmonary blastoma should be considered whenever epithelial cells and a separate population of stromal cells are seen in a pulmonary exfoliative cytology specimen.

Aged↗