Takehide Asano

Intraductal papillary mucinous tumors of the pancreas

BACKGROUNDnAn 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.nnnMETHODSnIntraductal 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.nnnRESULTSnThe 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.nnnCONCLUSIONSnIntraductal papillary mucinous tumors had a favorable prognosis after surgical treatment. A curative pancreatectomy should be indicated for this localized malignant tumor.

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

BACKGROUND/AIMSnWe 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.nnnMETHODSnGrafts 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.nnnRESULTSnThe 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).nnnCONCLUSIONSnThese 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.

Successful Gene Transfer Into Murine Pancreatic Islets Using Polyamine Transfection Reagents

SLET TRANSPLANTATION is considered to be the most theoretical option for insulin-dependent diabetes mellitus (IDDM). The islet graft survival is, however, still limited because of the difficulty of avoiding an acute rejection, despite of the use of immunosuppressant. To improve the results of clinical islet transplantation, a new approach to realize the complete inhibition of rejection should be developed. Gene transfection technique into the islets may become the new approach of immunosuppression and induction of the immunoacceptance. Retrovirus and adenovirus vector-mediated gene transfer technique, however, may not be suitable for clinical islet transplantation according to ethical view. Thus, in this study we examined the utility of the liposome-mediated gene transfer technique into murine pancreatic islets.

Assessment of energy status and fructose metabolism of liver in obstructive jaundice by 31P magnetic resonance spectroscopy.

The effect of cholestasis on hepatic energy status and fructose metabolism in jaundiced rats and patients was investigated using 31P magnetic resonance spectroscopy. Rats with obstructive jaundice (OJ group) were studied 7 days after bile duct ligation. Drainage rats were studied at 3 days (DR3 group) and 7 days (DR7 group) after the relief of 1 week obstruction of the common bile duct. In the bile duct ligated rat, the β‐adenosine triphosphate (ATP)/Pi (inorganic phosphate) ratio was significantly lower than in sham‐operated controls. This ratio recovered rapidly in the DR3 and DR7 groups. The maximum increase in the phosphomonoester peak (PMEmax) after an intravenous bolus of fructose was significantly reduced in both the OJ and DR3 groups, and was accompanied by a decrease in hepatic fructokinase activity. The PMEmax and the fructokinase activity recovered in the DR7 group. In a clinical study, the β‐ATP/Pi ratio in six healthy volunteers was comparable to that of 15 patients with obstructive jaundice, regardless of their biliary drainage status. The PMEmax in all patients (serum bilirubin ≥ 5 mg/dL), irrespective of biliary drainage, was significantly lower than in volunteers. Furthermore, the PMEmax in four of the eight patients with biliary drainage (serum bilirubin < 5 mg/dL) was lower than in volunteers. It is concluded that while energy status in jaundiced patients is well maintained, fructose phosphorylation is inhibited and recovery is delayed after the relief of obstruction compared with serum bilirubin. For the non‐invasive evaluation of damaged liver function in jaundice, 31P magnetic resonance spectroscopy is a useful technique.

Preoperative evaluation of residual liver function for extended hepatic resection with positron emission tomography and l-[methyl-11C] methionine

To evaluate residual liver functional reserve before major hepatectomy, volumetry of the residual liver was measured by computed tomography (CT) and the uptake of l-[methyl-11C] methionine of the residual liver was expressed by differential absorption ratio (DAR) with positron emission tomography (PET). Residual liver functional volume was quantified as the functional volume index (FVI). FVI of 11 normal whole liver was 8697 ± 2009 (mean S.D.). Cases, 11, of malignant liver tumors with obstructive jaundice underwent major hepatectomy. FVI of the eight patients (5561 ± 1087) who had good course after operation was significantly higher than that of the other cases (266 +- 685) died of liver failure (P < 0.005). FVI is a useful index to quantify residual liver functional reserve to avoid liver failure after major hepatectomy.

The effect of high-energy shock wave therapy combined with cisplatin on mouse hepatoma

It is well documented that high-energy shock waves (HESW) can produce antitumor effects in vivo and in vitro. Furthermore, because HESW can be focused on a limited area, this therapy is considered applicable to the treatment of localized cancer. In this study, we investigated the effects of HESW therapy combined with cisplatin (CDDP) on MH134 hepatoma in a mouse model. Tumor growth was inhibited by 1 mg/kg CDDP treatment in combination with 2,000 HESW administration, but not by 1 mg/kg CDDP treatment only. Moreover, the CDDP concentration in the tumor increased after HESW administration. The active oxygen induced by HESW was then investigated by the electron spin resonance system, and it was found that HESW generated hydroxy-radicals. As oxygen radicals have been reported to change cell membrane potential, it is supposed that active oxygen induced by HESW changes cell membrane permeability, and that CDDP is concentrated in the tumor. Therefore, the combined therapy with HESW and CDDP showed synergistic inhibitory effects on tumor growth.