Integrable systems in the realm of algebraic geometry -- after Mumford, Beauville and Vanhaecke

Beauville [A. Beauville, Jacobiennes des courbes spectrales et systèmes hamiltoniens complètement intégrables, Acta. Math. 164 (1990) 211-235] introduced an integrable Hamiltonian system whose general level set is isomorphic to the complement of the theta divisor in the Jacobian of the spectral curve. This can be regarded as a generalization of the Mumford system [D. Mumford, Tata Lectures on Theta II, Birkhäuser, 1984]. In this article, we construct a variant of Beauville's system whose general level set is isomorphic to the complement of the intersection of the translations of the theta divisor in the Jacobian. A suitable subsystem of our system can be regarded as a generalization of the even Mumford system introduced by Vanhaecke [P. Vanhaecke, Linearising two-dimensional integrable systems and the construction of action-angle variables

GLUTATHIONE S-TRANSFERASE PLACENTAL FORM IS A MARKER FOR BILE DUCT CARCINOMA, BUT NOT HEPATOCELLULAR CARCINOMA, IN HUMANS.

Immunohistochemical studies using anti-human glutathione S-transferase placental form (GST-π) rabbit antibody were carried out to investigate various hepatobiliary diseases in humans. Hepatocytes in fetal and adult liver without disease were negatively or positively stained while intra-or extrahepatic bile duct epithelial cells were positively or strongly positively stained with GST-π. Hepatocytes in regenerated nodules in liver cirrhosis were positively stained. Hepatocellular carcinomas were not strongly positively stained, while cholangiocarcinomas and cancers of the biliary tract were positively or strongly positively stained. These results indicate that GST-π staining is a useful marker for the diagnosis of intra-or extra-hepatic bile duct carcinomas in humans, and that enzyme activity is not phenotypically expressed in hepatocellular carcinomas

MALIGNANT ONCOCYTOMA OF THE PARANASAL SINUS

A case of malignant oncocytoma developing in the paranasal sinus of a 37-year-old Japanese man with a habit of heavy smoking is described. The primary tumor was found in the right maxillary sinus with local invasion to the nose and right ethmoidal sinus ; it was composed of nests of large oncocytic cells, with finely granular and eosinophilic cytoplasm, nuclear pleomorphism and prominent nucleoli, surrounded by proliferation of spindle-shaped cells in some areas. Electron microscopically, the cytoplasm of oncocytic tumor cells was characterized by abundant mitochondria, and immunohistochemical investigation revealed positive binding for antibodies to S-100 protein and α₁-antitrypsin, but a negative reaction for both cytokeratin and vimentin. At autopsy, metastatic nodules of tumor in the lungs, liver and pancreas independently exhibited both oncocytic cell- and sarcomatous cell compartments. This phenomenon is rare, and to the authors' knowledge, this would be histologically an ususual report of malignant oncocytoma with sarcomatous metastatic nodules arising from the paranasal sinus to be described in the literature

Regulation of the unfolded protein response via S-nitrosylation of sensors of endoplasmic reticulum stress

Protein S-nitrosylation modulates important cellular processes, including neurotransmission, vasodilation, proliferation, and apoptosis in various cell types. We have previously reported that protein disulfide isomerase (PDI) is S-nitrosylated in brains of patients with sporadic neurodegenerative diseases. This modification inhibits PDI enzymatic activity and consequently leads to the accumulation of unfolded/misfolded proteins in the endoplasmic reticulum (ER) lumen. Here, we describe S-nitrosylation of additional ER pathways that affect the unfolded protein response (UPR) in cell-based models of Parkinson's disease (PD). We demonstrate that nitric oxide (NO) can S-nitrosylate the ER stress sensors IRE1α and PERK. While S-nitrosylation of IRE1α inhibited its ribonuclease activity, S-nitrosylation of PERK activated its kinase activity and downstream phosphorylation/inactivation or eIF2α. Site-directed mutagenesis of IRE1α(Cys931) prevented S-nitrosylation and inhibition of its ribonuclease activity, indicating that Cys931 is the predominant site of S-nitrosylation. Importantly, cells overexpressing mutant IRE1α(C931S) were resistant to NO-induced damage. Our findings show that nitrosative stress leads to dysfunctional ER stress signaling, thus contributing to neuronal cell death

Development of stepping measurement device for evaluation of and training in walking

日常生活で杖をついたり,老人車などを押したりなど歩行能力の低下した人に対する簡便･安価で効果的な歩行訓練方法,訓練機器はない｡歩行能力の低下した人が体の移動を伴う歩行訓練をする場合,常に転倒の危険性を伴うために,介護者が必要であったり,転倒の不安のために動作が消極的になり,訓練の効果が半減する｡これに対して,ゆっくりとした足踏みは歩行能力の低下した人に対しては下肢筋力の強化,バランス訓練となり,歩行能力を向上させる｡しかし,足踏みが適切におこなわれているか,訓練の効果の程度についての評価ができなかった｡そこで,歩行能力の評価･訓練のために足踏み状態をモニタすることができる足踏み測定器を開発した｡本装置は,足踏みをするマット2枚およびノートパソコンなどから構成されている｡足踏み中における両脚立脚,左右それぞれの片脚遊脚の状態をマットスイッチのON,OFF状態にて判断する｡測定後,歩数,平均両脚立脚時間,平均片肺立脚時間などの解析･表示を行う｡最後に歩行能力が低下した被験者の足踏みを測定して,杖歩行など日常の歩行状態と足踏みの状態との関係を示し,足踏み測定の有効性についても検討した｡Although gait training equipment such as the bicycle ergometer and treadmill exists for patients whose walking ability is high, there is no appropriate gait training method or training instrument for patients whose walking ability has become impaired, who often use a cane or walker, etc. in the course of daily life. In the case of gait training for persons whose walking ability involves impaired locomotion, there is always the danger of a fall. Consequently, a caregiver is required, and the effect of the training is cut by half because the patient's anxiety about falling is exacerbated. Slow stepping affords strengthening and balance training of the leg muscles for patients whose walking ability has become low, and walking ability is improved. However, whether such training appropriately carries out stepping and the degree of the effect of such training has not been evaluated. Therefore, we have developed a stepping measurement device that monitors stepping for evaluation and training of walking ability. This system consists of two mat switches for stepping, a measuring circuit for stepping detection, and a book-sized personal computer with a PC card-type AD converter. This system can detect a left or right single stance phase and a double stance phase relative to the ON, OFF condition of the mat switch. After measurement, the following items are analyzed and displayed: ・number of steps, ・average time of double stance phase, ・the average time of single stance phase, and so on. Finally, we measured the stepping of subjects whose walking ability is low, and showed the relationship between daily walking conditions and stepping conditions. The effectiveness of this system was considered in light of the results