Analyses of the circadian clock using a cricket as an experimental animal: Functional analysis of the clock gene period in circadian rhythm generation

フタホシコオロギでは､分子生物学的手法が開発されつつある｡ここでは､最近われわれが試みているRNA干渉による､フタホシコオロギ(Gyyllus bimaculatus)の時計遺伝子perの機能解析を紹介した。幼虫頭部での解析により､per mRNAの発現量は､夜の始めにピークをもつリズムを示し､このリズムは恒暗･恒温条件下でも継続することが明らかとなり､perの時計機構への関与が示唆された。そこで､per dsRNAを用いたRNA干渉により､per遺伝子の役割を検討した。幼虫へのper dsRNAの投与により､per mRNAレベルは対照群の25%にまで減少し､かつほとんどの個体で活動リズムが消失することがわかった。これらの結果はコオロギでもperがリズムの発現に重要な役割を担うことを示唆している。さらに､終齢幼虫にper dsRNAを投与した場合も､羽化後の活動が恒暗条件下で無周期となることがわかった。これらの結果から､コオロギではperが時計機構に必須であることが示唆された。また同時に､RNA干渉が時計遺伝子の機能解析に極めて有効な手段であることが確認された

Preparation of Titanium Tetrachloride : Some Experiments for the Determination of its Mechanism

As one of the fundamental experiments on the preparation of titanium tetrachloride, several chlorinations such as that with and without carbon by chlorine gas, that by the mixed gas of chlorine and carbon monoxide, and that by carbon tetrachloride vapour are examined using titanium dioxide and its lower oxides as the material. By the results, it is known that the ignition temperature generally becomes lower as the titanium content in the oxides increases, but it is exceptional in case of the chlorination by the mixed gas of chlorine and carbon monoxide

Effect of activated protein C on plasma plasminogen activator inhibitor activity in patients with acute myocardial infarction treated with alteplase Comparison with unfractionated heparin

AbstractObjectivesWe examined whether activated protein C (APC) is an effective conjunctive therapy to thrombolysis in patients with ST-segment–elevated acute myocardial infarction (AMl).BackgroundActivated protein C possesses both systemic anticoagulant and anti-inflammatory properties. It has been also shown to enhance fibrinolysis by inhibiting plasminogen activator inhibitor (PAI) activity in vitro.MethodsAfter successful thrombolysis with alteplase, study patients were assigned to receive one of the two conjunctive therapies for 48 h intravenously: human plasma-derived APC at 0.06 mg/kg per day (APC group, n = 9) or unfractionated heparin at 100 to 400 U/kg per day, adjusted to maintain an activated partial thromboplastin time at 1.5 to 2 times of the control level (heparin group, n = 10).ResultsAdverse events, including reocclusion of the recanalized infarct-related coronary artery and major or minor hemorrhagic complications, occurred more frequently in the heparin group (4 of 10 cases) than in the APC group (none of 9 cases) (p = 0.033). In the heparin group, plasma PAI activity (IU/ml, median value [range]) was increased continuously from 8 to 24 h after thrombolysis and peaked at 24 h (30.9 [11.3 to 38.5]); on the other hand, it was not increased in the APC group at 24 h after thrombolysis (11.3 [0.0 to 31.0], p < 0.01 vs. heparin group).ConclusionsAdministration of APC suppressed increasing of plasma PAI activity observed after thrombolysis in patients with AMI. The effect of APC could be more eligible, compared with heparin, as a conjunctive regimen to thrombolysis in AMI patients