Keizō Sugimachi

We identified seven alternatively spliced forms of human 8-oxoguanine DNA glycosylase (OGG1) mRNAs, classified into two types based on their last exons (type 1 with exon 7: 1a and 1b; type 2 with exon 8: 2a to 2e). Types 1a and 2a mRNAs are major in human tissues. Seven mRNAs are expected to encode different polypeptides (OGG1-1a to 2e) that share their N terminus with the common mitochondrial targeting signal, and each possesses a unique C terminus. A 36-kDa polypeptide, corresponding to OGG1-1a recognized only by antibodies against the region containing helix-hairpin-helix-PVD motif, was copurified from the nuclear extract with an activity introducing a nick into DNA containing 8-oxoguanine. A 40-kDa polypeptide corresponding to a processed form of OGG1-2a was detected in their mitochondria using antibodies against its C terminus. Electron microscopic immunocytochemistry and subfractionation of the mitochondria revealed that OGG1-2a locates on the inner membrane of mitochondria. Deletion mutant analyses revealed that the unique C terminus of OGG1-2a and its mitochondrial targeting signal are essential for mitochondrial localization and that nuclear localization of OGG1-1a depends on the NLS at its C terminus.

OBJECTIVE: To identify the perioperative risk factors for postoperative bile leakage after hepatic resection, to evaluate the intraoperative bile leakage test as a preventive measure, and to propose a treatment strategy for postoperative bile leakage according to the outcome of these patients. SUMMARY BACKGROUND DATA: Bile leakage remains a common cause of major complications after hepatic resection. METHODS: Between January 1985 and June 1999, 781 hepatic resections without bilioenteric anastomosis were performed at the authors' institution. Perioperative risk factors related to postoperative bile leakage were identified using univariate and multivariate analysis. The characteristics of patients with intractable bile leakage and the effect of intraoperative bile leakage test were also examined. Management was evaluated in relation to the outcomes and the clinical characteristics of the patients with bile leakage. RESULTS: Bile leakage developed in 31 (4.0%) of 781 hepatic resections. This complication carried high risks for surgical death (two patients [6.5%] died). The stepwise logistic regression analysis identified high-risk surgical procedure, in which the cut surface exposed the major Glisson's sheath and included the hepatic hilum (i.e., anterior segmentectomy, central bisegmentectomy, or total caudate lobectomy), as the independent predictor of the development of postoperative bile leakage. None of the 102 cases in which an intraoperative bile leakage test was performed were subsequently complicated by postoperative bile leakage, and the preventive effect of the test was statistically significant. Patients with fisterographically demonstrable leakage from the hepatic hilum and with postoperative uncontrollable ascites had poor outcomes. CONCLUSION: Patients with bile leakage from the hepatic hilum and postoperative uncontrollable ascites tend to have a poor prognosis. Therefore, especially when a high-risk surgical procedure is performed in patients with liver cirrhosis, more careful surgical procedures and use of an intraoperative bile leakage test are recommended.

The purpose of this study was to clarify the factors linked to recurrence of small hepatocellular carcinomas, up to 3 cm in diameter, after hepatectomy. Fifty patients with small hepatocellular carcinomas who underwent hepatectomy between 1976 and 1988 were observed for possible recurrence for at least 2 yr. These patients were divided into two groups: 20 patients who had recurrence within 2 yr and 30 patients who had no recurrence within 2 yr. The recurrence pattern was analyzed by hepatic angiography. Statistical analysis by the chi 2 test and stepwise logistic regression showed that the risk factors linked to recurrence were (a) tumor diameter greater than 2.2 cm, (b) intracapsular infiltration of tumor cells, (c) tumor location deep in the liver, (d) macroscopical and microscopical tumor invasion into the portal vein and (e) tumor invasion into the portal vein or intrahepatic metastasis. When patients diagnosed with small hepatocellular carcinomas have any of these risk factors, postoperative adjuvant therapy and follow-up should be particularly carefully considered, since these patients are at high risk for early recurrence.

Abstract We compared the results of curative resection for carcinoma of the stomach in 254 patients who underwent simple resection (SR) and 454 patients who underwent extensive regional lymph node dissection (ELD). The 5‐year survival rates of the 2 procedures were significantly different in carcinoma involving the serosa of the stomach; it was 45% in the ELD group and 18% in the SR group ( p < 0.001). In patients with regional lymph node metastasis we obtained a 5‐year survival rates of 39% and 18% by ELD and SR, respectively ( p < 0.001). The incidence of metastasis to the secondary lymph nodes, removable only by ELD, was higher in cases with carcinomatous invasion of the deeper layers of the gastric wall, and this may have been the reason why ELD proved to be more effective than SR. ELD is discussed in relation to the site of the primary carcinoma and the extent of lymph node metastasis .