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T Kenmochi

Publications and source records attributed to T Kenmochi.

At least 37 records · Page 2Linked to original sources

Risk of bile duct carcinogenesis after excision of extrahepatic bile ducts in pancreaticobiliary maljunction.

BACKGROUND: A reflux of pancreatic juice into the biliary tract caused by pancreaticobiliary maljunction (PBM) has been considered important in the development of biliary tract carcinogenesis in choledochal cysts. We excised extrahepatic bile ducts in patients with choledochal cysts to terminate the reflux of pancreatic juice. We investigated whether this surgery could stop the development of the residual bile duct carcinoma. METHODS: Fifty-six patients with a diagnosis of PBM with choledochal dilatation underwent surgical excision of extrahepatic bile ducts. We applied a person-year method to compare the relative risks (observed number/expected number) of biliary tract carcinoma before and after surgery. RESULTS: In 3 patients, bile duct carcinoma developed in residual dilated segments 19 years 6 months, 8 years 8 months, and 2 years 5 months, respectively, after surgery. Although the relative risk in the post-surgery group was slightly decreased by surgery, it was still high compared with that of the general population. CONCLUSIONS: The incidence of bile duct carcinoma is still high, even after excision of extrahepatic bile ducts in PBM patients with choledochal dilatation. For these patients, careful long-term follow-up is necessary, especially after operations that leave the dilated bile ducts, such as cases of Todani's type IV-A.

Adolescent↗

Frequent expression of inducible nitric oxide synthase in esophageal squamous cell carcinomas.

Nitric oxide (NO) plays important biological roles in cardiovascular, nervous and immune systems, and is synthesized by nitric oxide synthase (NOS). Intracellular NO is known to cause DNA damage as a mutagen. We examined the expression of cytokine-inducible NOS (iNOS) in human esophageal squamous cell carcinomas. Weak iNOS immunoreactivity was seen in the basal and parabasal layers of non-neoplastic esophageal stratified squamous epithelium. iNOS expression was detected in 50 (87.7%) of the 57 esophageal squamous cell carcinomas, regardless of the depth of tumor invasion, histological differentiation and lymph node status. Early-stage cancers, i.e. mucosal squamous cell carcinomas, also showed significant iNOS expression. We speculate that increased iNOS expression is associated with the carcinogenesis of human esophageal cancer.

Adult↗

Virtual pancreatoscopy of mucin-producing pancreatic tumors.

We used computer-based virtual endoscopy techniques as a novel approach to clarify the three-dimensional (3D) surgical anatomy of the pancreas and of mucin-producing pancreatic tumors. Thirteen cases (18 lesions) of mucin-producing pancreatic tumors were investigated by virtual pancreatoscopy. Virtual endoscopic images were generated with virtual endoscopy software application on UNIX workstations. We created surface-rendered virtual endoscopic images derived from a computer reconstruction of the cross-sectional magnetic resonance imaging data. Virtual endoscopy could visualize the surfaces of the pancreatic duct and the bile duct, and also demonstrated all cystic tumors. The surfaces of malignant mucin-producing pancreatic tumors were illustrated as being more irregular than those of benign lesions. The virtual endoscopic technique could demonstrate not only a surface-rendered endoscopic image of the tumors but also a 3D reconstructed image of the pancreas. The relationship to anatomic structures located outside the surfaces is continuously maintained and displayed at the same time. Virtual pancreatoscopy was useful for surgical planning of minimally invasive resection of the pancreas.

Adenocarcinoma, Mucinous↗

The effects of prostaglandin E1 and tyrosine kinase inhibitors on energy status and protein synthetic ability in hepatic ischemia-reperfusion injury.

The effects of prostaglandin E1 (PGE1) and tyrosine kinase inhibitors on hepatic energy status and protein synthesis in ischemic livers were studied using 31P-magnetic resonance spectroscopy in a rat model. The continuous administration of PGE1 significantly increased the beta-adenosine triphosphate/inorganic phosphate (beta-ATP/Pi) ratio and hepatic protein synthesis rate (HPS) after ischemia-reperfusion injury. Microscopic examination showed that the continuous administration of PGE1 inhibited the development of sinusoidal hemorrhage and edema. Thus, it was concluded that PGE1 has a beneficial effect on ischemia-reperfusion injury in the liver. Pretreatment with tyrosine kinase inhibitor also increased the beta-ATP/Pi ratio; however, when tyrosine kinase inhibitor was injected before ischemia, the HPS became significantly reduced. Based on these data, the protective effect of tyrosine kinase inhibitor is unconvincing.

Alprostadil↗

LAP-1 cold preservation solution for isolation of high-quality human pancreatic islets.

The most critical factors that affect the outcome of clinical pancreatic islet transplantation are the number and quality of donor islets available for transplantation. Toward this goal, we attempted to obtain islets that are both of better quality and higher number than are obtainable by the islet-isolation process that is now widely used. We paid special attention to two critical components of the isolation procedure: minimizing the exposure of pancreatic tissue and freed islets to warm enzyme solution, and development of a preservation solution suitable for islets during cold storage of digested pancreatic tissue-free islets. For this purpose, we developed both a two-step procedure for pancreas digestion and a new cold preservation solution, the LAP-1 solution (Los Angeles preservation solution 1). In this study, we evaluated the effect of four preservation solutions by storing digested pancreatic tissues on ice for 90 min. After the cold storage, islets were purified on three layers of Euro-Ficoll solutions in a 50-ml tube, and the islet yield, viability, and function were determined. These experiments were performed by using samples from 10 consecutive islet isolations. Results with LAP-1, original University of Wisconsin solution (oUW), and modified UW solution (mUW;UW without hydroxyethyl starch) were compared with those obtained with Hank's balanced salt solution (HBSS). The islet yield was significantly higher in the LAP-1 and mUW groups as compared with the HBSS group (p < 0.01). The islet purity was significantly better in the LAP-1, oUW, and mUW groups than the HBSS (p < 0.001). The islet viability was lowest in the HBSS group immediately after purification (vs. LAP-1, oUW, and mUW, p < 0.05) and further decreased during culture (p < 0.01). Both the number and viability of cultured islets were the highest with LAP-1 solution but without statistical significance between mUW and oUW. Electron microscopic examination showed only slight damage to cell membranes immediately after purification of islets stored in LAP-1 solution and their complete recovery within 1-2 days of culture. These islets also exhibited normal insulin responses to high glucose by static incubation and perifusion assays.

Adolescent↗

A case of gallbladder adenomyomatosis with pancreaticobiliary maljunction and an anomaly of the cystic duct joined the common channel.

A 46-yr-old woman was admitted to our hospital with mild epigastric pain. Ultrasonography and computed tomography revealed an extremely thickened gallbladder wall. Endoscopic retrograde cholangiopancreatography demonstrated that the main pancreatic duct joined the nondilated common bile duct at the outer point of the duodenal wall (P-C type of pancreaticobiliary maljunction), and the cystic duct joined the common channel directly. The intraoperative amylase levels of the bile juices both in the common bile duct and the cystic duct were high. A cholecystectomy was performed. The wall of the gallbladder was markedly thick, yellowish, elastic, and soft. Histologically, Rokitansky-Aschoff sinus proliferation, hypertrophy of smooth muscles, and fibrosis were seen. The diagnosis was a generalized type of adenomyomatosis. The pathogenesis of the adenomyomatosis was believed to result from chronic stimulation as a result of pancreatic juice reflux. The etiology of this unusual type of junction was considered to be the result of the combination of pancreaticobiliary maljunction and an anomaly of lower junction of the cystic duct.

Adenomyoma↗

[Hepatic arterial infusion chemotherapy (HAI) for advanced hepatocellular carcinoma inefficacious with transcatheter arterial embolization (TAE)].

For 6 patients with advanced hepatocellular carcinoma (HCC) in whom TAE was inefficacious, we tried hepatic arterial infusion chemotherapy. 5-FU 500 mg/day + CDDP 10 mg/day was administered during 5 days. The AFP level was decreased for 4 patients, and 2 patients showed a partial response in CT image. These 2 patients have been alive over 22 and 18 months, respectively. These results suggest that 5-FU + CDDP HAI might be a useful treatment of HCC inefficacious with TAE.

Aged↗

Hepatic protein synthesis rate of liver specimens as a predictor of viability in rat cold ischemia liver transplantation model.

BACKGROUND/AIMS: We have previously reported that the hepatic protein synthesis rate, calculated as the uptake rate of L-[4.5 3H] leucine by the protein fraction during a 10-min incubation of a 16-G needle biopsy specimen of liver tissue, represents a high level of liver function and is therefore useful for evaluating liver function. We investigated the hepatic protein synthesis rate level in a pre-transplant liver to learn if it might predict the outcome in a rat orthotopic liver transplantation model. METHODS: Grafts were stored, liver specimens were obtained using a 21-G Chiba type II skinny needle, and the hepatic protein synthesis rate was calculated. Subsequently, liver transplantation was performed, and the hepatic protein synthesis rate level of revascularized liver, tissue blood flow rate, serum alanine aminotransferase, lactate dehydrogenase, hyaluronic acid, ketone body rate, and 2-week survival were examined. RESULTS: The hepatic protein synthesis rate of pretransplant liver was correlated with parameters of post-transplant liver function: hepatic protein synthesis rate of the revascularized liver (r=0.92, p<0.0001), tissue blood flow rate (r=0.77, p<0.004), serum alanine aminotransferase (r=-0.69, p<0.003), lactate dehydrogenase (r=-0.54, p<0.03), hyaluronic acid (r=-0.86, p<0.0002), and ketone body rate (r=0.57, p<0.02). Pretransplant hepatic protein synthesis rate in survivors was 263.6+/-54.2 nmol/mg protein/10 min, while that in nonsurvivors was significantly lower at 162.0+/-39.0 (p<0.0001). When evaluation was made using a logistic regression model, the accuracy predicted using the value of hepatic protein synthesis rate was 95% (19/20). CONCLUSIONS: These results suggest that measuring the hepatic protein synthesis rate of the grafts with a 21-G Chiba type II skinny needle may be a predictive criterion in the assessment of graft viability.

Alanine Transaminase↗

Inhibition of growth and invasive activity of human pancreatic cancer cells by a farnesyltransferase inhibitor, manumycin.

The effects of manumycin, a competitive farnesyltransferase (FTase) inhibitor, on pancreatic cancer cell lines with or without K-ras mutation were studied. Manumycin inhibited the growth of human pancreatic cancer cells (SUIT-2, MIA PaCa-2, AsPC-1, BxPC-3) in a dose-dependent manner. The 50% inhibitory concentration (IC50) in cell lines with a mutant K-ras gene (SUIT-2, MIA PaCa-2, AsPC-1) was lower than that in BxPC-3 with a wild-type ras. Both mitogen-activated protein kinase activity after growth stimuli and the ability for chemotactic invasion were markedly more inhibited by manumycin in SUIT-2 than in BxPC-3. These results suggest that mutated Ras is more sensitive to manumycin than the wild type. Furthermore, tumor growth and liver metastasis in nude mice inoculated with manumycin-treated SUIT-2 cells were inhibited dose dependently. Inhibition of Ras activity might be a new anticancer strategy in pancreatic cancer in which Ras plays a role.

Alkyl and Aryl Transferases↗

A two-step digestion process and LAP-I cold preservation solution for human islet isolation.

Pancreatic islet transplantation has a high potential for treating diabetes mellitus, but long-lasting insulin independence has not been achieved in type I diabetic patients. In order to obtain better results, improvement is needed in many areas. The first area is the islet isolation process. The requirements for an islet isolation method are: 1) to produce a maximum number of healthy islets without demanding a high quality of donor pancreas; 2) to be able to perform the procedure with fewer numbers of personnel who may be without extensive skills and expertise; and 3) to lower isolation costs. In order to achieve these objectives, we have made two important modifications to the isolation process. One is the development of a new preservation solution, LAP-I and the other is the use of a two-step process for pancreas digestion, involving a short warm collagenase digestion, followed by cold mechanical digestion without collagenase. We also use a clear plastic digestion chamber in order to visualize the process. The chamber cover is designed to facilitate frequent removal of digested tissue fragments. The overall procedure is simple and straightforward, requires less manpower and is cost effective. Our procedure is described in detail, and its advantages are discussed.

Adenosine↗