Biomedical subjects

T Uchida

Publications and source records attributed to T Uchida.

1,516 records · Page 85Linked to original sources

PubMedDate not supplied

Metabolic N-demethylation of 1,3-bis[[1-cycloheptyl-3-(p- dimethylaminophenyl)ureido]methyl]benzene dihydrochloride, a novel acyl-coenzyme A:cholesterol acyltransferase inhibitor.

The metabolism of 1,3-bis[[1-cycloheptyl-3-(p-dimethylamino- phenyl)ureido]methyl]benzene dihydrochloride (YM17E) in rat liver microsomes was investigated. After incubation of YM17E with rat liver microsomes in the presence of NADPH, a significant amount of YM17E was consumed and several products appeared. The structures of these products were identified by thermospray-linked LC/MS. By comparison of fragmentation patterns between these products and authentic compounds, five metabolites were eventually identified. All five metabolites--termed M1, M2-a, M2-b, M3, and M4--were sequentially formed through N-demethylation. The formation of these metabolites was NADPH-dependent, and was inhibited by SKF-525A, metyrapone, and carbon monoxide, which are inhibitors of cytochrome P-450. These results suggest that N-demethylation of YM17E is one of the main pathways of its biotransformation, and that this metabolism is catalyzed by cytochrome P-450-mediated monooxygenase.

Animals↗

PubMedDate not supplied

Simultaneous hepatic resection with pancreato-duodenectomy for metastatic pancreatic head carcinoma: does it improve survival?

BACKGROUND/AIMS: To determine whether aggressive surgery, consisting of a simultaneous pancreatic and partial hepatic resection, for patients with an invasive metastatic ductal adenocarcinoma of the pancreatic head improves the postoperative outcome. MATERIALS AND METHODS: A total of 109 patients with adenocarcinoma of the pancreatic head were divided into two groups. Group 1 consisted of 33 patients with liver metastasis and Group 2 consisted of 76 patients without liver metastasis. Group 1 was further subdivided into 11 patients(Group 1-A) to aggressive surgery, consisting of pancreatoduodenectomy and partial liver resection, and 22 patients to palliative bypass surgery(group 1-B). Group 2 was subdivided into 37 patients to pancreatoduodenectomy(group 2-A), and 39 patients to bypass surgery(group 2-B). RESULTS: No significant statistical differences were seen in the outcomes between Group 1-A (median survival period: 6 months) and Group 1-B (median survival period: 4 months). Further, all Group 1-A patients died from multiple recurrent liver metastasis within a year. In addition, the outcomes of Group 1-A were significantly poorer than that of 2-A patients(median survival period: 24 months). CONCLUSION: Patients who underwent an aggressive simultaneous resection of primary and metastatic hepatic lesion did not exhibit any improvement. However, it is anticipated that these findings will provide insights into developing an effective adjuvant therapy to impede or destroy macroscopic/occult liver metastasis.

Adenocarcinoma↗

PubMedDate not supplied

Evaluation of complete denture occlusal contacts using pressure-sensitive sheets.

This study evaluated the efficacy of a new occlusal analysis system (Dental Prescale System) composed of pressure-sensitive sheets and a computer for analysis for complete denture wearers. In the laboratory portion of the study, the system registered values that were greater than the actual applied loads (mean 6.3 +/- 10.6 N). Clinical measurements of five parameters related to the analysis of occlusion were made using two groups: 50 wearers of nonadjusted complete dentures and 50 wearers of adjusted prostheses. An error discrimination rate of 16% resulted between the two groups. This system is capable of measuring occlusal pressure at every contact point and can be considered a useful method for occlusal analysis and patient screening.

Bite Force↗

PubMedDate not supplied

Pancreatic duct patency after pancreaticogastrostomy: long-term follow-up study.

BACKGROUND/AIMS: To clarify whether the pancreatic duct remains patent during long-term follow-up of patients after pancreaticogastrostomy. In a previous study of pancreaticogastrostomy with post-operative follow up for 3 years after surgery, we found that the orifice of the pancreatic duct was difficult to detect in some patients because of swelling of the gastric mucosa. Previous studies have not examined pancreatic duct patency during long-term follow-up. METHODOLOGY: Between July 1985 and August 1989, 20 patients underwent a pylorus-preserving pancreaticoduodenectomy with reconstruction by pancreaticogastrostomy. Five of these patients were followed up post-operatively for more than 9 years to determine the patency of the pancreatic duct. All pancreatic anastomoses were performed by the telescopic method. RESULTS: All 5 patients were female, with a mean age of 65.4 years (range: 54-75). Median post-operative follow-up was 10.8 years (range: 9-12). The indications for surgery were carcinoma of the ampulla of Vater in 4 patients and chronic pancreatitis in 1 patient. Pancreatic duct patency was confirmed in 4 patients by gastroscopy and pancreatography. However, the anastomotic orifice could not be detected in the remaining patient because of complete coverage by the gastric mucosa. In this patient, pancreatic exocrine and endocrine function deteriorated with dilation of the distal pancreatic duct. The patient underwent a second operation involving dissociation of the pancreatico-gastric anastomosis and resection of about 1 cm of the fibrous, proximal portion of the pancreas. Reconstruction was performed with a Roux-en-Y pancreaticojejunostomy and a mucosa-to-mucosa anastomosis. CONCLUSIONS: Although pancreaticogastrostomy has been applied as a safe and straightforward method for reconstruction after pancreaticoduodenectomy, anastomotic stenosis is a potential late complication of this approach.

Aged↗