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Purpose: Imaging with 99mTc-sestamibi (99mTc-MIBI) has been used to assess 170-kDa P-glycoprotein (P-gp) expression and predict chemotherapy responses in several types of malignancy, such as breast and lung cancers. The purpose of this study was to evaluate the relationship between 99mTc-MIBI accumulation in tumors and sensitivity to chemotherapy in gastric cancer patients. Experimental Design: Thirty-six patients with advanced gastric cancer underwent 99mTc-MIBI scintigraphy before chemotherapy. Patients also underwent endoscopic biopsy, and the expression of P-gp or multidrug resistance-associated protein was analyzed by immunohistochemical staining. The relationship between the accumulation of 99mTc-MIBI in tumors and responses to chemotherapy with 5-fluorouracil/cis-diamminedichloroplatinum(II) or epirubicin was examined. Results: Higher accumulation of 9mTc-MIBI in tumors was observed in 25 and 23 of 36 gastric cancer patients at the early (30 min) and delayed (120 min) images, respectively. Accelerated accumulation of 99mTc-MIBI negatively correlates with increased expression of P-gp, but not of multidrug resistance-associated protein, as determined by immunohistochemistry in gastric cancer tissues. The response rate to 5-fluorouracil/cis-diamminedichloroplatinum(II) chemotherapy in patients with high 99mTc-MIBI accumulation (15.4%) was much lower than that in patients with low 99mTc-MIBI accumulation (54.5%). In contrast, patients with high 99mTc-MIBI accumulation show a higher response rate (41.7%) to chemotherapy with epirubicin, which is known to be a substrate of P-gp transporter. Conclusions: 99mTc-MIBI scintigraphy is useful to suggest the responses to chemotherapy of patients with advanced gastric cancer.

症例は80歳の男性で, 心窩部痛, 右季肋部痛および黄疸を主訴に近医受診し, 肝S5に径5cm大の腫瘍を指摘され当科紹介となった. HBsAg (-), HBcAb (-), HCVAb (-). 胃前庭部後壁にも腫瘍性病変を認め, 血清AFP, PIVKA-II, CEA値はいずれも異常高値であった. 術前診断は3型胃癌の肝転移とし, 胃亜全摘術, 肝右葉切除術を施行した. 胃病変はT1 (sm, IIa+IIc), 肝腫瘍は白色調で硬く被膜を有さず, 右肝管1次分枝内に腫瘍栓を伴っていた. 胃肝両病変ともに充実性配列主体の低分化腺癌 (hepatoid-adenocarcinoma) の像を呈し, 類似の免疫組織染色パターンであることから, 胃低分化腺癌の肝転移と診断した. AFP, PIVKA-II産生T1胃癌の報告は少なく, 胆管腫瘍栓を伴う転移性肝癌も非常にまれである. 胃癌の幼若化現象, 癌胎児性抗原産生の面から興味深い症例であると考えられる.

Background. Cellular functions are maintained by a continuous supply of ATP, which is supplied efficiently by mitochondrial oxidative phosphorylation. Since myoglobin, found in cardiac myocytes and red skeletal muscle, but not in the liver, facilitates oxygen diffusion under low oxygen conditions and enhances oxidative phosphorylation, this study seeks to enhance hepatic ATP levels and attenuate ischemia-reperfusion injury in rodent livers by adenovirus-mediated myoglobin expression. Material and methods. After infecting Hep3B and rodent livers with adenovirus carrying CMV promoter sequences linked to the human myoglobin gene (AdCMVMyo), reverse transcriptase-PCR and immunodetection for myoglobin, and cellular and hepatic ATP levels were examined. The effect of myoglobin was evaluated in a hepatic ischemia-reperfusion model in the rat. Results. Myoglobin expression was confirmed in Hep3B and rat livers after AdCMVMyo infection. The ATP levels in Hep3B cells and C57BL/6 mice livers 72 h after AdCMVMyo transfection were significantly higher than control levels and those after adenovirus-mediated β-galactosidase transfection. Finally, expression of myoglobin attenuated ischemia-reperfusion injury in the rat liver. Conclusion. These results indicate that myoglobin gene transfer to the liver enhanced ATP levels both in vitro and in vivo and might be a novel strategy to reduce ischemia-reperfusion injury.

固有肝動脈瘤に対して, 術前3次元画像診断を施行し治療方針および術式決定に有用であった1例を経験した. 症例は65歳の男性. 肝嚢胞の経過観察中に腹部CT検査にて固有肝動脈瘤を偶然発見された. 血管造影を施行したが, 動脈瘤と左右肝動脈の分岐形態が明確に描出されず, 3次元CT検査および3次元CT内視鏡画像(cruising eye view)により血管分岐形態, さらには動脈瘤内部の形態が容易に把握でき, 安全に固有肝動脈瘤切除および動脈再建を施行しえた. 本症例のような腹腔内臓器動脈瘤症例では, 3次元CT検査が術前診断のみならず術式決定にも有用であり, 積極的に施行されるべきであると考える.

This study investigated whether prostaglandin E1 (PGE1) could reduce hepatic injury to the liver graft caused by harvesting and 24-h preservation in University of Wisconsin (UW) solution in a canine model. The PGE1-treated group was intravenously administered 0.5 microgram/kg per minute of PGE1 for 30 min before harvesting, as well as a concentration of 1 mg/l PGE1 in the washout and UW solutions. In both the PGE1-treated and the control group, all recipients survived for 1 week or more after transplantation. Arterial ketone body ratio (AKBR) remained over 1.0 in the early postoperative period. The PGE1 group showed significant reductions in guanase, GOT, and LDH during the early postoperative period compared to the untreated control group. Histological examination disclosed partial mitochondrial swelling, hepatocyte vacuolation, and necrosis in the control group, while such abnormalities were rarely seen in the PGE1 group. These results suggest that PGE1 can effectively reduce hepatic injury to liver grafts preserved in UW solution prior to transplantation.

The size of segmental liver grafts assessed by preoperative computed tomography (CT) volumetry was evaluated in relation to surgical outcome in 14 living related partial liver transplantations (LRLTs). The aim was to show that graft size can be accurately assessed before operation and to estimate the lower safety limit of graft size in assessing subsequent graft function and survival. The relationship between calculated CT volume and weight of the liver was linear in the recipient (r = 0.97) and donor (r = 0.98). The mean (s.e.m.) modified liver weight ratio (MLWR; ratio of graft weight to recipient's expected liver weight based on body-weight) was 0.59(0.07) (range 0.27–1.09). Surgical complications related to an oversized graft and primary graft failure caused by a small-for-size graft were not observed. The lowest MLWR of any survivor was 0.27. These results suggest that a partial liver graft reduced to about 30 per cent of the recipient's expected liver weight can tolerate LRLT well.

This study was designed to investigate the influence of intracellular ionized calcium ([Ca2+]i) on the induction of c-fos, c-jun, c-myc, and hsp70 genes after oxidant stress induced by xanthine/xanthine oxidase (X/XOD) treatment or after heat shock using primary cultures of rat proximal tubule epithelium (PTE). X/XOD (500 microM/25 mU/mL) induced all of these genes; ionomycin also resulted in similar kinetics of induction of all genes. The expression of both c-fos following X/XOD treatment and hsp70 following heat shock was markedly decreased through chelation of [Ca2+]i by Quin 2/AM. The c-fos expression following X/XOD treatment was partly reduced by a protein kinase C inhibitor, staurosporine (ST), and markedly inhibited by another protein kinase inhibitor, 2-aminopurine (2AP), while both ST and 2AP markedly reduced hsp70 expression. The ADP-ribosylation transferase inhibitor 3-aminobenzamide had no effect on either c-fos or hsp70 expression. These results suggest that cell injuries leading to increased [Ca2+]i in PTE result in induction of c-fos, c-jun, c-myc, and hsp70; and that the activation of c-fos and hsp70 genes may be regulated by [Ca2+]i and [Ca2+]i-dependent protein kinases.

Background In ischemia/reperfusion (I/R) injury, a massive generation of reactive oxygen species (ROS) after reperfusion is a critical factor. Rac, a member of the Rho GTPase superfamily, plays important roles in the production of ROS and activation of nuclear factor-κB (NF-κB) in vitro. However, the exact role of Rac in the ROS production and NF-κB activation in vivo after I/R is still obscure. Methods We blocked Rac1 activity in the rat liver using adenovirus encoding a dominant negative rac1 mutant (Ad5N17Rac1) and examined whether inactivation of Rac1 could prevent ROS generation in the hepatic I/R injury. Seventy-two hours after the adenoviral infection, hepatic I/R was induced by Pringle's maneuver for 20 minutes, followed by reperfusion in the rats. Results Ad5N17Rac1 infection significantly attenuated ROS production after reperfusion and suppressed the hepatic injury. Furthermore, N17Rac1 suppressed NF-κB activation and messenger RNA expression of tumor necrosis factor-α (TNF-α) and inducible nitric oxide synthetase (iNOS). Ad5LacZ, a control adenovirus, had no effect on the induced hepatic I/R injury, nor did it affect NF-κB activation. Immunohistochemical analysis of NF-κB (p65) revealed that translocation of p65 to the nucleus after reperfusion was blocked in many of non-parenchymal cells (NPCs) and in hepatocytes in the Ad5N17Rac1-infected liver. Conclusion We conclude that Rac1 is required in ROS generation and NF-κB activation after hepatic I/R in vivo, and that inactivation of NF-κB in NPCs and suppression of ROS generation in NPCs and hepatocytes possibly account for the protective effect of N17Rac1 in this study.

Background/Aims: The ability to transfer foreign genes into the biliary tract would be useful for the treatment of biliary tract diseases, including cancer, cystic fibrosis and other genetic diseases. To introduce a foreign gene precisely into the rat biliary epithelial cells, we developed a new technique, inserting a polyethylene catheter into the common bile duct through the papilla of Vater by use of a fusigenic cationic liposome with hemagglutinating virus of Japan (HVJ-cationic liposome). Methods: Transfection efficiency was estimated with the use of FITC-oligonucleotides (FITC-ODNs) and cDNA of β-galactosidase (pCAG-lacZ). Results: FITC-ODNs encapsulated in HVJ-cationic liposome were effectively transfected into cell nuclei of human cholangiocellular carcinoma in vitro after a 30-min incubation as compared with the simple application of naked FITC-ODNs. After in vivo injection of FITC-ODNs using the HVJ-cationic liposome method through the papilla of Vater, fluorescence accumulation was observed only in the epithelial cells of the biliary tract, but not in the parenchymal cells of the liver. β-galactosidase expression was observed in the biliary epithelial cells 3 days after the transfection of pCAG-lacZ and was also detected at 14 days, but not at 28 days, without obvious cytotoxicity. Conclusions: HVJ-cationic liposome-mediated gene transfer to the biliary tract via the papilla of Vater is a minimally-invasive and an effective gene-delivery method for site-specific targeting to the epithelial cells of the biliary tract, which could be applied to the treatment of human biliary tract diseases.

Role of cytosolic Ca 2+ and protein kinases in the induction of the hsp70 gene. The role of cytosolic Ca 2+ ([Ca 2+ ] i ) and protein kinases in the hsp70 induction following heat shock was investigated in cultured rat proximal tubular epithelial (PTE) cells. Changes in [Ca 2+ ] i were measured by digital imaging fluorescence microscopy using fura 2. Steady state levels of hsp70 mRNA were examined by either Northern or dot blot analyses. [Ca 2+ ] i increased within 10 minutes and continued to increase following heat shock. The increases in [Ca 2+ ] i were reduced in nominally Ca 2+ -free media with or without EGTA. [Ca 2+ ] i also increased within 0.5 minutes following ionomycin, but then declined to normal levels by 1.0 to 1.5 minutes. Heat shock induced hsp70 mRNA within 15 minutes, which continued to increase up to three hours. Ionomycin also induced hsp70 mRNA, which peaked at 30 minutes, and gradually decreased thereafter. The hsp70 induction following heat shock was attenuated when extracellular Ca 2+ was reduced. Chelation of [Ca 2+ ] i by quin-2 also reduced the hsp70 induction. Inhibitors of protein kinases, 1-(5-isoquinolinylsulfonyl)-2-methylpiperazine (H-7), calphostin C, genistein, and 2-aminopurine, also had inhibitory effects on the hsp70 induction. In contrast, a calmodulin inhibitor, chlorpromazine, had little effect. These results suggest that heat shock increases [Ca 2+ ] i in rat PTE cells and that [Ca 2+ ] i and protein kinases are involved in the hsp70 induction following heat shock.

The transcription factor NF-KB has anti-apoptotic properties and may confer chemo-resistance to cancer cells, NF-KB is constitutively activated in bladder cancer, breast cancer, and melanoma, in which cancer cell lines, inhibition of NF-KB induces cell death in bepatocellular carcinoma (HCC), constitutive activation of NF-KB was tbund more frequently in tumor tissue compared with non-tumor tissue. Our AIM is to clarify the role of NF-KB in camptothecin-induced apoptosis of HCC. METHODS: Studies were performed in 3 hepatoma cell lines, Hep3B, HepG2 and Huh7. Camptothecin-induced apoptosis was evaluated wath DNA [addering assay" and DNA fragmentation ELISA. Western blot analysis for NF-KB (p65) and IKB were performed with nuclear extracts and whole lysates, respectively, to examine the activation of NF-KB by, camptothecin. To block NF-KB activation, adenov~rus expressing IKB super-repressor (Ad5IgBsf) was intected with ceils 12 hours befm'e the treatment of camptothecin We examined whether camptothecin (0.5-2 t~M)-iuduced apoptosis was enhanced under transt~ction of Ad5IKBsr (50-200 MOI) by" DNA fragmentation ELISA. RESULTS DNA laddering was clearly shown alter 1-2 p.M of camptnthecin treatment in all 3 HCC cells. DNA fragmentation ELISA demonstrated that the rate of apoptotic cell death in Hep3B was 20% lower than that of HepG2, indicating that Hep3B is resistant to camptothecininduced apoptosis. The pretreatment of cyclobeximide (to block the protein symthesis) with Hep3B did not enhance camptothecin-induced apoptosis. NF-KB was constitutively activated in Hep3B and camptothecni enhanced the translocation of NF-KB to the nucleus from 30 to 120min after camptothecin. After 12 hours of AdSIKBsr infection, we confirmed the expression of IKB super-repressor in Hep3B However, inactivation of NF-KB by Ad5lKBsr did not sensitize Hep3B to camptothecin-induced apoptosis in Hep3B in Conchision, HCC chemo-resistance to camptothecin is through NF-,~rB-independent pathway.

Concerning Cr-Mo steels used actually for motor shafts, etc. by Japanese National Railways, we examined their mechanical properties with the same test material, especially tensile strengths, strains, contractions and rotational bending fatigue strengths.As a result of our experiments, in which we compared the effects of the difference of forging ratio and heat treatment conditions, or those of standard specimens and sectional parts of large size materials given on statical tension and fatigue strengths, we found various differences in data.About the standard specimens, we could not find any difference in influences of heat treatment conditions on statical tension data. But the fatigue strengths of materials oil-or water-tempered were larger than those of materials air-tempered.Also, the effects of the difference in forging ratio did not appear in the statical tension experiments, but appeared a little in the rotational bending fatigue tests.On the other hand, about the sectional parts of large size specimens (840°C HWQ-680°C OT or AT), we found fairly large differences, namely in yielding p't σs, tensile strength σB, and fatigue strength σwb; data of outer layer parts were larger than those of inner parts.The tensile strength was in a range of 78-92kg/mm2, and the fatigue strength was about 37-41kg/mm2.

When containing small holes of faults which are the source of fatigue fracture, or when their inner fatigue limits are lower than outer ones, materials are often cracked from inner parts.In this report, by an illustration of large size rotational bending fatigue test, the author relates the mechanism of fatigue fracture started from inner parts.