Hepatic infarction following abdominal interventional procedures.

To clarify the incidence, background, and progress of hepatic infarction following interventional procedures, cases of hepatic infarction following interventional procedures at our department during the last decade were identified by reviewing the clinical records of 1982 abdominal angiography and interventional procedures and records of abdominal CT. Nine episodes (0.5%) in 8 patients were identified as hepatic infarction following an interventional procedure. Five episodes were preceded by embolization of the hepatic or celiac artery at emergency angiography for postoperative bleeding with hemorrhagic shock. Three episodes followed the elected interventional procedure for hepatocellular carcinoma, and the remaining episode occurred after 12 months of chemoinfusion through an indwelling catheter in the hepatic artery and portal vein. Hepatic arterial occlusion in all episodes and portal venous flow abnormality in 5 episodes were observed on angiography. Four patients whose liver function was initially impaired died of hepatic infarction, although the extent of the disease on CT did not appear to be related to the mortality. Multiple risk factors, including arterial insufficiency, were observed in each patient. The incidence of hepatic infarction following interventional procedures in this series was low but sometimes fatal, and occurred most frequently in emergency embolization in hemorrhagic shock.</p

Hierarchical communities in the walnut structure of the Japanese production network

This paper studies the structure of the Japanese production network, which includes one million firms and five million supplier-customer links. This study finds that this network forms a tightly-knit structure with a core giant strongly connected component (GSCC) surrounded by IN and OUT components constituting two half-shells of the GSCC, which we call a\textit{walnut} structure because of its shape. The hierarchical structure of the communities is studied by the Infomap method, and most of the irreducible communities are found to be at the second level. The composition of some of the major communities, including overexpressions regarding their industrial or regional nature, and the connections that exist between the communities are studied in detail. The findings obtained here cause us to question the validity and accuracy of using the conventional input-output analysis, which is expected to be useful when firms in the same sectors are highly connected to each other.Comment: 38 pages, 17 figure

Numerical analysis of bursting activity in an isolated pancreatic β-cell model

Pancreatic β-cells exhibit bursting electrical activity, which is correlated with insulin secretion. It has been reported that several ionic channels may contribute to the characteristic electrical activities of these cells but their mechanisms are still unclear. In this study, we examined how the characteristic electrical activity of isolated β-cells occurs. Using a simple mathematical model of pancreatic β-cells, we found that conductances of the voltage-sensitive mixed ion channel and voltage-sensitive potassium channel contribute to such electrical activity. In addition, we found that noise can play a key role in this activity. These results imply that the bursting electrical activity of pancreatic β-cells can be controlled by ionic conductances or noise. Such control enables medical application of β-cells in type II diabetes, wherein insulin secretion is difficult to control. Our findings may contribute to a novel treatment for type II diabetes

Acute Bowel Injury due to Cryoablation for Renal Cell Carcinoma: Correlated Radiologic and Pathologic Findings

An 87-year-old Japanese man underwent percutaneous cryoablation (PCA) therapy for his renal cell tumor. We displaced the colon from the tumor using hydrodissection. Computed tomography (CT) immediately after PCA was indicative of iceball extension to the colon wall, and a discontinuous enhancement of the colon wall was observed. We therefore performed an emergency surgery. On laparotomy, we observed a dark-purple area on the affected area of the colon, and the resected specimen showed focal, deep ulceration on the mucosal surface. Photomicrography revealed mucosal necrosis, submucosal hemorrhage, and necrotic foci in the muscularis propria, corresponding to the discontinuous colon wall enhancement on CT and the deep ulceration and dark-purple area on laparotomy. He recovered from surgery and was discharged without any complications