Direct lymphatic spreading route into the liver from the gallbladder : an animal experiment using pig

In the special occasion that the physiological lymphatic flow is obstructed, gallbladder carcinoma (GBC)may spread into the liver via lymphatic route. Therefore, this study was conducted to find out the direct lymphatic route draining into the liver from the gallbladder using pigs with ligated cystic ducts. After injecting the carbon particle suspension (CH40) or the contrast medium (Lipiodol) into the subserosal layer of the gallbladder, the lymphatic route into the liver was examined both macroscopically and histologically. In controls, CH40 or Lipiodol drained along the cystic duct toward the hepatoduodenal ligament. After occlusion of cystic duct, CH40 was interrupted at the ligated point, and then spread into the liver nearby the gallbladder bed, running off to the liver hilus, toward the hepatoduodenal ligament. This route was confirmed by the Lipiodol drainage into the right median lobe of the liver, equivalent to the segments Vand IV a in humans. We presented for the first time the emergence of lymphatic drainage from the gallbladder into the liver after the occlusion of physiological lymphatic route using pigs. This implies that the direct spread into the segments Vand IVa of liver should be considered in the surgical treatment of advanced GBC

Evaluating Physical Protection Effectiveness of polypropylene spunbonded nonwoven fabric against Bark Stripping by Sika Deer (Cervus nippon yesoensis) using the Forest Cafeteria Tests

大径の母樹をエゾシカ食害から守る物理的防除資材として，施工柔軟性に富む不織布に着目した。その防除効果を東京大学北海道演習林内においてカフェテリア試験を行って評価した。都合84 セットのうち，試験が成立したのは45 セットであった。そのうち2 例において，エゾシカが不織布の上から囓ろうとした形跡が認められたが，不織布は破られておらず，樹皮に軽微な傷が付くに留まった。この2 例を除く43 セットでは，不織布で包んだ試験体は囓られた形跡が全く認められなかった。一方，45 セット全てで，不織布で包まない試験体（コントロール）は全周を喰われていた。これらの結果から，不織布はエゾシカ食害に対して防除効果が期待できると言える。The establishment of a conservation system of forest genetic resources and their genetic diversity is one of the principal aims of the University Forests of The University of Tokyo. We focused on polypropylene spunbonded nonwoven fabric (PP nonwoven) as a physically protective material for protecting seed trees from bark-stripping by sika deer. Its plasticity and lightness makes it easy to install on large seed trees across large natural forests.　Its effectiveness was evaluated in cafeteria tests at a local forest. The test was concluded when the logs without PP nonwoven wrappers were completely stripped of their bark by sika deer. In a total of 84 sets of test, in 45, although the logs without PP nonwoven wrapper were completely stripped of their bark, the wrapped logs were not. Only in two sets were the traces of nibbling by sika deer observed on wrapped logs. In the other 43 sets no such traces were found. These results indicate that PP nonwoven wrapping is effective for the protection against bark-stripping by sika deer