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We have investigated flux flow dissipation in typical two kinds of HTS tapes, i.e., a Bi-2223 multi-filamentary tape and a RE-123 coated conductor (CC) from the view point of heat load under over current conditions. Based on systematic measurements on current-voltage characteristics, the nonlinear flux flow dissipation has been described analytically by taking into account current sharing in metallic sheath or stabilization layer. Flux flow dissipation in the RE-123 CC shows much steeper temperature dependence than that of the Bi-2223 tape. As a result, attainable cooling power becomes smaller in the RE-123 CC in comparison with that of Bi-2223 tape even if the same cooling condition. In other word, acceptable temperature rise in the RE-123 CC is small at over current condition, whereas moderate temperature dependence in the Bi-2223 tape allows stable operation even if the bias current exceeds the critical current. Influence of spatial inhomogeneity in the both HTS tapes has also been investigated. Longitudinal variation of local critical current, Ic, and its statistical behavior have been characterized by use of reel-to-reel scanning Hall probe microscopy. It has been found that the flux flow dissipation is possibly localized more than one order higher than that of the average value due to discrete local Ic drops.

Surgical indications or method of resection for intraductal papillary mucinous neoplasm of the pancreas (IPMN) are controversial. The aim of the current study was to evaluate surgical indications including cancer prevention and selection of specific surgical procedures. A group of 244 patients who underwent pancreatectomy for IPMN from 1981 to 2005 was examined retrospectively for clinicopathologic features. Carcinomas (carcinoma in situ + invasive carcinoma) were observed in 72% of the patients with main duct IPMN. The mural nodules for patients with carcinomas were larger than 3 mm. The maximum diameter of branch duct IPMN for patients with borderline atypia was larger than 30 mm. Lymph node metastasis and extrapancreatic invasion were observed only in patients with invasive carcinoma. In limited pancreatic resection, pancreatic fistulae were observed in 7.9% of patients. The indication for IPMN resection, including for cancer prevention, is lesions above IPMN with borderline atypia (main duct IPMN, mural nodule ≥3 mm, maximum diameter of branch duct IPMN ≥30 mm). A pancreatectomy with lymph node dissection should be performed for invasive IPMNs and a limited pancreatic resection has a role for noninvasive IPMNs.

Background Although local recurrence of advanced esophageal cancer is frequent after definitive chemoradiotherapy (CRT), the clinical benefit of salvage esophagectomy has not been elucidated. Methods We reviewed 27 patients with squamous-cell cancer who underwent esophagectomy after definitive CRT (≥50 Gy) (salvage group) and 28 patients who underwent planned esophagectomy after neoadjuvant CRT (30 to 45 Gy) (neoadjuvant group). Results The preoperative albumin level and vital capacity were significantly lower in the salvage group than in the neoadjuvant group. Two patients (7.4%) from the salvage group who underwent extended esophagectomy with three-field lymphadenectomy died of postoperative complications, but no deaths occurred after less-invasive surgery. There was no difference of overall postoperative survival between the salvage and neoadjuvant groups. Conclusions The outcome of salvage esophagectomy after definitive CRT was similar to that of planned esophagectomy after neoadjuvant CRT. Less-invasive procedures might be better for salvage esophagectomy because of the high operative risk.

Background Control of blood loss is a crucial problem during hepatectomy. Bleeding from the inflow system can be controlled by the Pringle maneuver or selective vascular occlusion. Bleeding from the outflow system is closely related to central venous pressure (CVP). Therefore, in this study, we evaluated whether vascular outflow control by clamping the inferior vena cava (IVC) below the liver (IVC clamping) during hepatectomy is a safe and effective method to reduce blood loss and CVP. Methods We reviewed the outcomes of 103 consecutive patients whose CVP values were >5 cm H 2 O and who had undergone right or left hemihepatectomy between 1995 and 2000. Forty-seven patients who underwent hepatectomy with IVC clamping (Group A) between 1998 and 2000 were compared with the previous 56 patients who underwent hepatectomy without IVC clamping between 1995 and 1997 (Group B). Results The CVP decreased by 3.7 cm H 2 0 after IVC clamping. Estimated blood loss was 910 mL in Group A and 1177 mL in Group B. ( P = .008) No severe renal or cardiovascular damage occurred after IVC clamping. Conclusions IVC clamping is very effective in reducing blood loss during hepatectomy when the CVP is elevated and cannot be reduced pharmacologically or by fluid restriction.

Background: The effectiveness of liver segmentectomy or larger resection in patients with hepatocellular carcinoma (HCC) 2 cm or less in greatest diameter has not been clarified. Methods: From 1985 to 1994, 125 patients with solitary HCC 2 cm or less in greatest diameter underwent curative hepatectomy (liver segmentectomy or larger resection, 94; subsegmentectomy, 31). The relationship between clinicopathological findings and surgical outcomes were examined. Results The 5- and 10-year survival rates were 68% and 47%, respectively. Univariate and multivariate analysis showed the Child-Pugh class to be a significant prognostic factor. However, liver segmentectomy or larger resection did not have any significant effect on long-term survival. Conclusions Our data suggest that no further improvement of the survival rate can be achieved by liver segmentectomy or larger resection, compared with subsegmentectomy in patients with solitary HCC 2 cm or less in greatest diameter.

Background: There is a high risk of anastomotic leakage after pancreaticojejunostomy after pancreaticoduodenectomy (PD) in patients with a normal pancreas because of the high degree of exocrine function. These PD are therefore generally performed using a stenting tube (stented method). In recent years, we have performed pancreaticojejunostomy with duct-to-mucosa anastomosis without a stenting tube (nonstented method) and obtained good results. Methods: The point of this technique is to preserve adequate patency of the pancreatic duct by carefully picking up the pancreatic duct wall with a fine atraumatic needle and monofilament thread. The results of end-to-side pancreaticojejunostomy of the normal pancreas were compared between the nonstented method (n = 109) and the stented method (n = 39). Results: There were no differences in background characteristics between the groups, including age, gender and disease. The mean duration to complete pancreaticojejunostomy was 26.6 min in the nonstented group and 29.2 min in the stented group. The mean durations of surgical procedure and intraoperative blood loss were also similar in the groups. Morbidity rates due to early postoperative complications were 20.2 and 23.1%, with pancreatic leakage occurring in 7.3 and 7.7% of patients, respectively. These differences were not statistically significant. One patient in the stented group died of sepsis following leakage of pancreaticojejunostomy. There were also no significant differences in the mean time to initiation of solid food intake or postoperative hospital stay. Conclusion: We conclude that a stenting tube is unnecessary if the duct-to-mucosa anastomosis is completely performed. This operative technique can be considered a basic procedure for pancreaticojejunostomy because of the low risk.

Color Doppler energy (CDE) offers a marked improvement in sensitivity over existing color Doppler systems. We report here the use of this system in the diagnosis of small hepatocellular carcinoma (HCC). CDE was used in the clinical investigation of 13 nodules in 12 suspected cases of HCC less than 2 cm in diameter. Findings were compared with those on color Doppler imaging (CDI), angiography, angioechography and histological examination. The apparatus consisted of an Acuson 128XP 10 (ART) with 4- and 5-MHz transducers. Comparison of angiography, angioechography and CDE findings: CDE showed pulsatile flow in 8 of the 9 nodules (88.9%) in which angiography showed tumor stain or angioechography showed positive enhancement. In the 3 nodules in which staining was negative and angioechography showed negative or non-enhancement, CDE showed no pulsatile flow. Comparison between pathological and CDE findings: All 7 nodules which showed moderate or poor differentiation in pathology showed continuous pulsatile flow on CDE. Among 5 well-differentiated HCC, 4 showed no pulsatile flow and 1 showed intermittent pulsatile flow. The remaining non-malignant nodules showed no pulsatile flow. Comparison between CDI and CDE findings: Both CDI and CDE showed pulsatile flow in 8 nodules but with marked differences in sensitivity. Flow was intermittent or spotty with CDI, but mostly showed a continuous branched pattern with CDE. Thus, CDE images correlated well with angiography, angioechography and pathological findings. CDE is an effective and non-invasive means of determining the hemodynamics of small nodules and is useful in the diagnosis of small HCC.

We succeeded in producing the liver metastatic model of human hepatocellular carcinoma in athymic nude mice.The tumor, which was surgically obtained from a 59-year-old man with macro-trabecular hepatoma, was cut into small pieces and inoculated subcutaneously in athymic BALB/c nude mice. This transplanted tumor showed spontaneous liver metastases in 100% after the 3rd generation. There were also a few metastases in the spleen and lung. The metastatic liver tumors were resected and transplanted subcutaneously in other nude mice and, at present, the 18th generation has been maintained with 100% metastasizing characterization. All mice inoculated with this tumor were dead within 8 weeks due to liver metastases. The expression of intercellular adhesion molecule-1 (ICAM-1) was recognized on this tumor surface, however, a metastasizing capacity of this tumor could not be inhibited by pre-treatment of tumors with antibody against ICAM-1. Human leukocyte antigen (HLA) class I was also recognized, but lymphocyte function-associated antigen-1 (LFA-1) was not recognized. In the serum of tumor-transplanted nude mice or the medium of in vitro tumore culture, IL-1, IL-6 and type IV collagenase were not shown. This tumor also did not show the human platelet-aggregating activity. This spontaneous liver metastatic model was very rare and it was suggested that this model could be a useful tool for investigating the mechanism of liver metastasis of human hepatoma.

The relationship between aplastic anemia and viral hepatitis is well recognized, and such patients usually have a high mortality. We successfully treated a case of aplastic anemia following living-related orthotopic liver transplantation (LROLT) for non-A, non-B, non-C hepatitis. A 2-yr-old boy with fulminant hepatic failure from non-A, non-B, non-C hepatitis received LROLT. Before transplantation, he had pancytopenia which was probably hepatitis associated, and viral suppression was suspected after bone marrow (BM) biopsy. After the transplantation, he developed progressive pancytopenia and a diagnosis of aplastic anemia was made via BM biopsy. With immunosuppressant agents (cyclosporine, methylprednisolone), cytokine therapy (granulocyte-colony stimulating factor (G-CSF), macrophage-colony stimulating factor (M-CSF), recombinant human erythropoietin (rhEPO)) was effectual and the patient recovered from pancytopenia. He was discharged from the hospital 57 d after the liver transplantation and remains well 1 yr after LROLT. Combined cytokine therapy with high doses of G-CSF, M-CSF and rhEPO appeared to be effective in the treatment of aplastic anemia following liver transplantation for non-A, non-B, non-C hepatitis. Since M-CSF activates macrophages, it may have contributed to the graft rejection. Careful consideration should be given to the use of high-dose M-CSF in liver transplant patients.

Recently, 3D image in endoscopic ultrasonography has been developed, so that examination become easier than 2D image. However, is it offer better result than 2D image. We investigated if it is useful for determination of the depth of cancer invasion and what factors influence the result. Ultrasound imaging system (Olympus Co.) is used. The method: Anticholinergic agent or glucagon is injected in order to suppress the peristalsis andthe 2 channel scope was inserted to the lesion vicinity. After the lesion is observed, the probe was inserted from the working channel, and water was irrigated from the other channel. When the lesions was covered the water, the scan was carried out. To stop respiration was directed under scan. One of the judgment of the depth of cancer invasion by images from radial scan, the other judgment of the depth of cancer invasion by made liner image, simulation three-dimensional image or multiple images from the computer taken images, they were separately determined. In 50 cases of esophageal cancer and 47 cases of gastric cancer, each results were compared with histological findings. Result 1. In esophageal cancer, the probe passed through the carcinoma in 49 cases, and whole scanning was possible in 98%. In judgment from radial scan, Tis and cancer invading the lamina propria were correctly determined in 67%, the cancer invading the muscularis mucosa (including slightly invasion the submucosa) in 59%, the submucosa in 92% , T2 in 100%, T3 in 63% , T4 in 100% and total on 72%. On the other hand judgment from images by computer, Tis and cancer invading the lamina propria were accurately determined in 83%, cancer invading the muscularis mucosa (including slight invasion the submucosa) in 66%, cancer invading the submucosa in 92%, T2 in 100%, T3 in 73%, T4 in 100% and total in 80%. 2. In gastric cancer, the judgment from radial scan, mucosal cancer was correctly determined in 81%, cancer invading the submucosa in 92% , T2 in 33% and total 81%. On the other hand, the judgment from images by taken computer, mucosal cancer was accurately determined in 84%, cancer invading the submucosa in 100%, T2 in 67% and total in 85%. 3. In the image with the big tumor, the invasion depth became the inaccuracy by the attenuation. The most important point in the judgment from images by computer was that judgment was made two direction, consecutive images of lesions. Conclusion: EUS 3D images were offer more accurate judgments than 2D. Information from two-direction and consecutive images of the lesion let us precise judgments.

Twenty patients who showed superficial depressive type (type IIc) of early colorectal cancer were studied clinicopathologically. All patients were male with a mean age of 67 years. The chief complain was most frequent with positive fecal occult blood in 6 patients, and the type IIc lesion was pointed out by colonoscopy in all patients,. The tumor location was most frequent in transverse colon in 8 patients, and 16 of 20 patients (80%) in the right colon (cecum, ascending colon and transverse colon). The average size of the tumor was 11.3mm in diameter. On colonoscopy, the redness and the deformity of fold was seen in 16 patients (80%) and the conversing fold was in 2. Eleven patients had mucosal cancer and 9 patients had submucosal invasive cancer, and 1 patient had submucosal invasive cancer with lymph node metastasis. No recurrence was occurred in all patients after treatments. Seventeen of 20 patients (85%) had adenoma and 8 patients (40%) had the other colorectal adenocarcinoma. In conclusion, careful observation on colonoscopy are needed to detect type IIc lesion of which findings are reddening and deformities of the folds. The prognosis of type IIc of early colorectal cancer was favorable because the lymph nodes metastasis were seen in 1 patient and because no recurrence was occurred in all patients.

The aim of this paper is if higher frequency probe :30MHz provide better resolution and result. Equipment: 20,30MHz probes were used. The method: 1.Experiment: In order to analyze the difference between layer structure by 20MHz and one by 30MHz, 6 esophageal resected specimens were scanned by 20 or 30MHz in water tub. 2. Clinical use: Before examination, anticholinergic agent or glucagon is injected in order to suppress the peristalsis. The 2 channel scope was inserted to the lesion vicinity, the probe was inserted from the working channel, and water was irrigated from the other channel. The scan was carried out by 20 or 30MHz. Twentyone cases of superficial esophageal cancer were examined by 20 and 30MHz and each images were compared with histological findings. Result 1. Experiment: Normal esophageal wall was delineated 9 layers by 20 and 30MHz, however using 30MHz the 2nd and 4th layers became clear. 2. Clinical cases: Two epithelial cancer were delineated by 30MHz, but one of them was difficult to determine by 20MHz. The determination of cancer limited to the lamina propria was correctly determined in 78% by 30MHz, 67% by 20MHz. Cancer invading the muscularis mucosa or small invasion to the submucosa were correctly determined in 100% by 30MHz, in 67% by 20MHz. Cancer invading the submucosa was determined in 89% by 30 and 20MHz. Conclusion: 30MHz probe provide better image of the layers from the epithelium to the muscularis mucosa. Accordingly 30MHz is useful for determined indication of mucosal resection via endoscopy.