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T Kenmochi

Publications and source records attributed to T Kenmochi.

At least 19 recordsLinked to original sources
PubMed2005

The start of an islet transplantation program in Japan.

In Japan, pancreas donation had become possible from cadaveric donor sources, both heart-beating or non-heart-beating (NHB). Pancreas allografts have been distributed in the organ allocation system of the Japan Organ Transplant Network. Meanwhile, islet transplantation has been categorized as a tissue transplantation; it is free from legal restraints. Thus, pancreata for islet isolation must be obtained from NHB donors. Herein we report the starting program and preliminary results of islet transplantation in Japan. Selection and listing criteria for transplantation include regional priority, ABO blood type, previous islet transplant status with insulin independence, and a longer waiting time. Five institutes in Japan (Fukushima, Chiba, Kyoto, Kobe, and Fukuoka) are prepared to start programs. A two-layer cold storage method using perfluorocarbons and UW solution is recommended for pancreas preservation. Islet isolation and purification procedures are performed according to institute-specific protocol. Immunosuppression is based on sirolimus/tacrolimus combined with basiliximab induction. Two or three consecutive infusions of >5000 IE/kg are planned for each recipient until achieving insulin independence. Twenty-seven isolations and 14 transplants were performed in eight non-insulin-dependent diabetes mellitus (IDDM) recipients. Almost all (26 of 27) were NHB donors. All recipients are free from hypoglycemic episode after transplantation. One of these recipients is insulin independent; the others are currently on minimal doses of exogenous insulin. The feasibility of islet transplantation using NHB donors was confirmed using a two-layer cold storage method and a steroid-free immunosuppressive protocol, with a high rate of graft function.

Aged↗
PubMed2004

Simplified method for cryopreservation of islets using hydroxyethyl starch and dimethyl sulfoxide as cryoprotectants.

Cryopreservation is an ideal method for long-term storage of human islets. Dimethyl sulfoxide (DMSO) has been used as an intracellular cryoprotectant. However, because of its toxicity, DMSO has to be added stepwise and diluted stepwise with sucrose. We combined hydroxyethyl starch (HES) as an extracellular cryoprotectant with DMSO to simplify the freeze-thawing procedure. Islets were isolated from the pancreas of beagle dogs by an automated digestion method and Ficoll purification. After overnight culture, the islets were cryogeneically stored using cooling by a programmed freezing system. After 4-week storage in liquid nitrogen, the container was rapidly thawed in a 37 degrees C water bath. The function of the islets was assessed upon static incubation immediately after thawing, showing a recovery rate of 71.16% +/- 20.14% and a stimulation index of 1.80 +/- 0.78. In conclusion use of HES allowed a decrease in DMSO concentration and simplified the freeze-thawing procedure for islets.

Animals↗
PubMed2002

Esophageal hernia in dementia: surgeon's role for mixed-type esophageal hernia in an elderly woman with dementia.

The mixed-type esophageal hernia is an indication for operation to prevent stomach volvulus and perforation. However, preventive operation is meaningful depending on the physical status. We encountered an 84-year-old, demented, bed-ridden woman of mixed-type esophageal hernia complicated with severe reflux esophagitis. First, the patient was conservatively treated by intravenous hyperalimentation and H2 blocker but, with onset of delirium, she removed the venous route twice. Subsequently, she was tightly restrained to the bed to avoid removing the line. Ethical deliberation for the patient tightly fixed to the bed and intravenous alimentation for her life prompted us to reconsider hernia operation after discussion with surrogate decision makers. The patient recovered uneventfully after operation, and movement without intravenous route or without any restraints was maintained by oral feeding assisted by gastrostomy feeding. In the coming decade, when senior patients are expected to increase, such operations can be forwarded to respect the patients' quality of life.

Aged↗
PubMed2001

Prophylactic excision of the gallbladder and bile duct for patients with pancreaticobiliary maljunction.

HYPOTHESIS: Pancreaticobiliary maljunction (PBM) is a high-risk factor for biliary tract carcinogenesis because of a continuous reflux of pancreatic juice into the biliary tract. It remains to be disclosed whether we should perform prophylactic excision of gallbladders and bile ducts. DESIGN: A person-year method. SETTING: A university hospital. PATIENTS: We studied 68 patients with PBM treated between August 1, 1974, and December 31, 1999. MAIN OUTCOME MEASURES: Relative risks (observed number-expected number ratios) of gallbladder and bile duct carcinomas according to type of bile duct dilation (ie, cystic dilation, diffuse dilation, and nondilation). RESULTS: Observed number-expected number ratios of gallbladder carcinomas were high: 291.3 in 43 patients with cystic dilation, 167.2 in 16 patients with diffuse dilation, and 419.6 in 7 patients with nondilation. Observed number-expected number ratios of bile duct carcinomas were 194.2 in 43 patients with cystic dilation before surgery and 142.8 in 39 patients with cystic dilation after long postsurgical follow-up. All these values were statistically significant (P<.01). CONCLUSIONS: The gallbladder carries a high risk for carcinogenesis in all types of dilation in patients with PBM. The bile duct carcinomas of PBM were exclusively identified by the type of cystic dilation. Prophylactic cholecystectomy should be recommended for all dilation types, and prophylactic excision of bile ducts including cholecystectomy should be performed in patients with PBM and cystic dilation. Complete excision of extrahepatic dilated bile ducts and careful follow-up for carcinogenesis in residual dilated bile ducts should be recommended for patients with PBM and cystic dilation.

Adult↗
PubMed2001

Accumulation of p53 in esophageal squamous cell carcinoma.

p53 is one of the most important tumor suppressor genes. Mutation of the p53 gene can be detected immunohistochemically as over-expression of its protein in the nucleus. The p53 gene product is known to regulate cell growth and proliferation. Genetic alterations related to the carcinogenesis or progression of esophageal cancer are poorly understood. We examined accumulation of p53 protein in esophageal squamous cell carcinomas including early-stage cancers, and its clinicopathological significance. p53 immunoreactivity in the cancer tissues was found in 61 (79.2%) of 77 esophageal squamous cell carcinomas. Over-expression of p53 protein (diffusely and focally positive staining) was seen in 70.1% (54/77). p53 over-expression was detected not only in the cases of in situ or intramucosal carcinomas, but also in invasive carcinomas. No significant correlations were found between p53 over-expression and clinicopathological features such as depth of tumor invasion, lymph node metastasis or venous/lymphatic invasion. These results suggested that p53 mutations may be closely associated with the early-stage of pre-invasive esophageal carcinoma, and p53 gene mutations may play an important role in the carcinogenesis of human esophageal cancer.

Aged↗
PubMed2001

Preliminary study for sentinel lymph node identification with Tc-99m tin colloid in patients with esophageal or gastric cancer.

The purpose of this study is to determine whether a lymph node identified with high radioisotope (RI) activity is a sentinel node. We studied 26 patients with either esophageal or gastric cancer whose preoperative imaging studies showed no lymph node metastasis. Before surgery, Tc-99m tin colloid was injected via endoscopy into the submucosa. In lymph nodes dissected at surgery, RI activity was measured by a scintillation counter, and metastatic status was examined by hematoxylin-eosin staining. The number of dissected nodes was 45 +/- 15 (mean +/- SD) per patient, and the number of nodes with high RI activity was 4 +/- 1. Nodal metastasis occurred in 11 of 26 patients. In 9 of these 11 patients, metastatic foci were found in one or more nodes with high RI activity. In one of the 2 remaining patients, endoscopic clipping was applied just above the injection sites, and in the other patient, the tumor invasion was beyond the muscle layer. For further analysis, the case with clipping was excluded, and only those in which the tumor invasion was confined within the muscle layer were evaluated. Six of 18 patients in this analysis showed nodal metastasis. Each of the 6 patients had at least one node that showed high RI activity and that was positive for metastasis. We conclude that when tumor invasion remains within the muscle layer, lymph nodes with high RI activity can be regarded as sentinel nodes.

Aged↗
PubMed2000

Inferior head resection of the pancreas for intraductal papillary mucinous tumors.

BACKGROUND: Patients with intraductal papillary mucinous tumor have a favorable prognosis after surgical treatment. When this neoplasm is located in the head of the pancreas, resection has conventionally required pancreatoduodenectomy. Although pancreatoduodenectomy can now be performed with a low mortality rate, morbidity still occurs frequently. METHODS: Between November 1982 and January 1999, 38 intraductal papillary mucinous tumors of the pancreas were resected at the Chiba University Hospital. Seven patients (18%) underwent inferior head resection of the pancreas. In this preliminary study, the operative technique is presented, and its efficacy in improvement of quality of life is evaluated. RESULTS: Patients with intraductal papillary mucinous tumor underwent resection with no perioperative mortality. After discharge from hospital, 6 patients who underwent inferior head resection were still alive without recurrent disease after a median follow-up of 3 years. However, 1 patient developed peritoneal dissemination and died 18 months after inferior head resection. Patients had regained 98% of preoperative weight 1 year after inferior head resection. N-benzoyl-L-tyrosyl-p-amino-benzoic acid (BT-PABA) excretion test showed the same value before (73%) and after (73%) inferior head resection (n = 7). Pancreatic fistulas occurred more frequently after inferior head resection (38%), but the incidence of major complications was similar between inferior head resection and other types of pancreatic head resection. CONCLUSIONS: Pancreatic function was well preserved, and patients regained 98% of preoperative weight after inferior head resection of the pancreas. The authors concluded that the limited involvement of intraductal papillary mucinous tumors enables the surgeons to perform inferior head resection of the pancreas.

Adenocarcinoma, Mucinous↗
PubMed2000

Clinicopathological studies of esophageal carcinosarcoma: analyses of its morphological characteristics using endoscopic, histological, and immunohistochemical procedures.

BACKGROUND AND STUDY AIMS: Carcinosarcoma of the esophagus is a rare malignant neoplasm consisting of both carcinomatous and sarcomatous components, which characteristically forms polypoid tumors. PATIENTS AND METHODS: Seven carcinosarcomas were analyzed using endoscopic, histological, and immunohistochemical procedures. Endoscopically, six of the seven lesions were found to be of the protruding type, while the other one was an ulcerating tumor. RESULTS: In all seven cases, the carcinomatous component consisted of differentiated squamous cell carcinoma, and the sarcomatous component was spindle cell carcinoma. Histological analyses demonstrated that the majority of the protruding tumors consisted of the sarcomatous component, while the ulcerating tumor mainly consisted of squamous cell carcinoma. The Ki-67 (MIB-1) labeling index (LI) of the carcinomatous component (28.2%) did not differ significantly from that of the sarcomatous component (25.5%). The sarcomatous component showed abundant expression of type IV collagen and laminin. CONCLUSIONS: It is conceivable that the carcinomatous and sarcomatous components grow separately from the early stage of the tumors, and that the sarcomatous component forms a protruding tumor mass because it has abundant stroma positive for type IV collagen and laminin.

Aged↗
PubMed2000

Improved quality and yield of islets isolated from human pancreata using a two-step digestion method.

A new approach, involving a two-step digestion process and Los Angeles preservation solution #1 (LAP-1), a cold storage solution, was developed for isolation of high-quality islets from human pancreata for transplantation. This approach markedly improves the islet yield, purity and viability, and the isolation success rate. In this method, the pancreas was digested first in warm collagenase solution for up to 20 minutes. After decanting the enzyme solution, partially digested tissue was dissociated by gentle agitation in cold LAP-1 solution without additional collagenase. The digested tissues were stored in cold LAP-1 solution until islet purification on Euro-Ficoll. Forty-six islet isolations were performed consecutively by the new method (group 1). These results were compared to those obtained earlier with 46 consecutive isolations, using our previous method that had been used before development of the new method (group 2). Our old method was a modification of Ricordi's method involving only warm collagenase digestion and the storage of digested tissues in cold Hanks balanced salt solution. All pancreata were partial, containing the body and tail. There were no significant differences in both groups with regard to the donor age, cold ischemic time, harvesting conditions, and pancreatic weight. Pancreas digestion was completed in approximately 1 hour in both groups. The isolation success rate as determined by viable islets after 2 days in culture was 93.5% (43 of 46 cases) in group 1, and 56.5% (26 of the 46) in group 2. Immediately after isolation, the new method yielded a total of 335,739 +/- 36,244 islets equivalent to 150 microm (IEQ) and 6,233 +/- 681 IEQ/g of pancreas with 83 +/- 2.5% purity, whereas the old method yielded a total of 195,587 +/- 25,242 IEQ and 3,763 +/- 5,509 IEQ/g with 69.2 +/- 4.7% purity. Isolated islets in group 1 maintained a good three-dimensional structure, displayed normal insulin release to high glucose stimulation in vitro, and restored euglycemia after transplantation into streptozotocin-diabetic athymic mice. The two-step digestion method provides a sufficient number of islets for transplantation from a single pancreas.

Adolescent↗
PubMed2000

Stromal CEA immunoreactivity is correlated with lymphatic invasion of human esophageal carcinoma.

Carcinoembryonic antigen (CEA) is a good marker of colorectal cancer. Recent studies have demonstrated that CEA may function as a metastatic potentiator by different pathways; i.e. modulation of immune responses, facilitation of intercellular adhesion and cellular migration. However, expression patterns of CEA have not yet been established in human esophageal carcinomas. In this study, we examined CEA expression in human esophageal squamous cell carcinoma and its clinicopathological significance. CEA immunoreactivity was frequently detected in the cancer cells (cytoplasmic type; 81.1%, 43/53) as well as in the cancer stroma (stromal type; 32.1%, 17/53), regardless of the depth of tumor invasion. Lymphatic invasion of cancer cells was frequently found in the stromal CEA-positive esophageal cancer (44.4%, 16/36), compared to stromal CEA-negative cancer (5.9%, 1/17) (p<0.05). These observations suggested that stromal CEA expression plays important roles in lymphatic invasion of human esophageal squamous cell carcinoma.

Aged↗
PubMed2000

Frequent expression of sialyl Le(a) in human esophageal squamous cell carcinoma.

Sialyl Le(a) antigen (CA19-9), a member of a family of high molecular weight glycoproteins, was originally described as a gastrointestinal- and pancreatic-specific tumor marker. Recent studies have demonstrated that sialyl Le(a) is a ligand for E-selectin and may play an important role in tumor metastasis. However, expression patterns of sialyl Le(a) have not yet been established in human esophageal carcinomas. In this study, we examined sialyl Le(a) expression and its histopathological localization in human esophageal squamous cell carcinoma. Sialyl Le(a) immunoreactivity was detected in 28 (51.9%) of the 54 esophageal squamous cell carcinomas, regardless of the depth of tumor invasion, vascular invasion or lymph nodal status. In 13 cases (29.5%), significant sialyl Le(a) expression was detected not only in the intramucosal carcinoma components, but also in the invasive carcinoma components. These observation suggested that sialyl Le(a) expression is associated with early-stage cancer progression.

CA-19-9 Antigen↗
PubMed1999

Obstructive jaundice caused by a huge liver cyst riding on the hilum: report of a case.

A 71-year-old man presented to our hospital with obstructive jaundice, found to be caused by a huge liver cyst which was centrally located and riding on the hilum. Percutaneous transhepatic cyst drainage was performed, following which obstruction of the bile duct was relieved and the jaundice subsided. As jaundice recurred after removal of the drainage tube, the patient underwent deroofing, since when he has remained well. Only 13 cases of liver cysts producing obstructive jaundice have been reported in the English literature, most of which were characteristically enormous, located centrally, and riding on the hilum. Liver cysts possessing such features are likely to cause obstructive jaundice by compressing the hepatic hilum. Cyst drainage is helpful for ameliorating the jaundice and making an accurate diagnosis; however, subsequent deroofing or injection therapy is necessary to prevent recurrence.

Aged↗
PubMed1999

Intraductal papillary mucinous tumors of the pancreas.

BACKGROUND: An increasing number of intraductal papillary mucinous tumors of the pancreas have been reported in recent years. The indolent character and favorable prognosis of this neoplasm have been described. METHODS: Intraductal papillary mucinous tumors were classified into main duct type (n = 8) and branch type (n = 28) according to the dominant location of the tumor. This single-institute study examined the clinicopathological features and outcome after surgical resection in patients with intraductal papillary mucinous tumors. RESULTS: The gender, age, tumor size, and prognosis were quite similar for the main duct type and branch type groups. Branch type tumors were more frequently located in the head of the pancreas than were main duct type tumors. Histological examination revealed that 88% of main duct type tumors were adenocarcinomas; however, only 46% of branch type tumors were adenocarcinomas. Five-year survival rates for the patients with all main duct type tumors (n = 8), main duct type adenocarcinoma (n = 7), all branch type tumors (n = 28), and branch duct adenocarcinoma (n = 13) were 100%, 100%, 90.6%, and 90.9%, respectively. CONCLUSIONS: Intraductal papillary mucinous tumors had a favorable prognosis after surgical treatment. A curative pancreatectomy should be indicated for this localized malignant tumor.

Adult↗