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K Nishihara

Publications and source records attributed to K Nishihara.

187 records · Page 11Linked to original sources
PubMedDate not supplied

Sensitizing effects of gallium citrate on hyperthermic cell killing in vitro.

The lethal effects of gallium citrate in combination with heat were studied using four cell lines, L5178Y, FM3A, P388 and HeLa. Cells were incubated with different concentrations (0.2 2 mM) of gallium citrate at 37 degrees C for 24 h and heated at a range of temperatures from 40-44 degrees C for various time periods up to 6 h in the absence of gallium citrate. Survival and cell viability were determined by clonogenic assay and the dye-exclusion test, respectively. All of the cell lines tested were insensitive to heat below 41 degrees C, but were very sensitive to heat above 43 degrees C. Gallium citrate was cytotoxic to these cell lines at different levels: P388 and HeLa were far more sensitive than L5178Y and FM3A. The killing effects of heat at 41 degrees C were greatly enhanced by gallium citrate in L5178Y and P388 cells. The Arrhenius analysis for the lethal effect of heat, determined by clonogenic assay, in L5178Y cells showed that the transition temperature was remarkably decreased for the gallium-treated cells from approximately 43 degrees C to 41 degrees C. The mechanism for this decrease in the transition temperature may be attributable to the additional effects of gallium citrate on energy metabolism. Preincubation with 0.05 mM gallium citrate at 37 degrees C for 7 days also enhanced heat sensitization at 41 degrees C in L5178Y. This preincubation condition may correspond to the condition for the continuous infusion of gallium that is clinically used for cancer treatment. In contrast, treatment with gallium did not greatly enhance the sensitivity of FM3A or HeLa cells to heat at 41 degrees C, but the effects of gallium were significant.

Adenosine Triphosphate↗
PubMedDate not supplied

"CT angiogram sign" in obstructive pneumonitis and pneumonia.

OBJECTIVE: The "CT angiogram sign" in dynamic pulmonary CT consists of enhanced branching pulmonary vessels in a homogeneous hypoattenuating consolidation of lung parenchyma and is reportedly useful for diagnosing lobar bronchioloalveolar cell carcinomas. MATERIALS AND METHODS: To identify cases exhibiting the CT angiogram sign, we retrospectively reviewed the reports of 5,500 dynamic incremental CT examinations of the chest. RESULTS: We identified the CT angiogram sign in five patients with obstructive pneumonitis due to lung tumors and four patients with pneumonias. CONCLUSION: The CT angiogram sign can be observed in pulmonary consolidation of varying etiologies.

Adenocarcinoma, Bronchiolo-Alveolar↗
PubMedDate not supplied

Sialylated MUC1 mucin expression in normal pancreas, benign pancreatic lesions, and pancreatic ductal adenocarcinoma.

BACKGROUND/AIMS: Pancreatic cancer has the poorest prognosis of all gastrointestinal cancers. Because sialylated mucin influences the biologic behavior of carcinoma cells, we investigated sialylated MUC1 mucin expression in patients with pancreatic ductal adenocarcinoma. METHODOLOGY: The expression of sialylated MUC1 mucin was examined in 55 pancreatic ductal adenocarcinomas, 2 normal pancreas specimens, 3 chronic pancreatitis specimens, 1 ductal hyperplasia of the pancreas, 3 mucinous cystadenomas, and 2 liver metastases from pancreatic ductal adenocarcinoma. Expression was assessed by immunohistochemistry with a new monoclonal antibody (mAb) (MY.1E12). RESULTS: Sialylated MUC1 mucin was expressed in the cancer cell membrane in all the ductal carcinomas. The reaction product was seen at the apical aspect of cells when these were in tubule formation. This pattern was also detected in mucinous cystadenomas. However, it was seen diffusely in the cell membrane in single cancer cells or small clusters of cells without tubule formation and in metastatic liver tumors. Namely, invading or metastatic cancer cells expressed this type of mucin throughout the entire cell membrane. The expression of sialylated MUC1 mucin was not observed in specimens from normal pancreas, chronic pancreatitis, or ductal hyperplasia of the pancreas. In normal pancreas and these lesions, expression of sialylated Mession of sialylated MUC1 was limited to acini and secreted mucin. CONCLUSIONS: Sialylated MUC1 mucin, which is expressed throughout the cancer cell membrane, may be a factor in the metastatic potential of pancreatic ductal adenocarcinoma.

Adenocarcinoma↗
PubMedDate not supplied

The differential diagnosis of pancreatic cysts by MR imaging.

BACKGROUND/AIM: The usefulness of magnetic resonance imaging (MR imaging) in the differential diagnosis of cystic lesions of the pancreas was assessed. METHODS AND MATERIALS: Pseudocyst was present in 9 patients, retention cyst in 4, simple cyst in 2, serous cystadenoma in 1, mucinous cystadenoma in 6, mucinous cystadenocarcinoma in 6. The relative signal intensity (SI) of each cystic lesion on MR imaging was assessed in comparison with that of the liver. RESULTS: It was difficult to distinguish the cystic types from each other based on the SI on MR images. Insofar as mucinous cystic tumors, those containing gelatinous mucin showed higher SI on T1-weighted images than those containing mucinous but watery fluid. five of the 6 mucinous cystic tumors containing gelatinous mucin were histologically malignant, whereas all except one those containing watery fluid were benign. CONCLUSIONS: Our results suggest that the SI on T1-weighted images may be useful in distinguishing malignant from benign mucinous cystic tumors.

Adult↗