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The sonodynamically-induced in vitro and in vivo antitumor effects of mono-l-aspartyl chlorin e6 (NPe6) was investigated.Both in vitro and in vivo antitumor effects were tested in combination with ultrasound at 2 MHz.The rate of ultrasonically-induced damage on isolated sarcoma 180 cells in air-saturated suspension was enhanced two-fold with 80 μM NPe6. The co-administration of 25 mg/kg NPe6 followed by ultrasonic exposure at 2 MHz suppressed the growth of implanted colon 26 cell tumors at an intensity at which ultrasound alone showed only a slight antitumor effect.These in vitro and in vivo results suggest that NPe6 is a potential sensitizer for sonodynamic tumor treatment. The enhancement of cell damage by NPe6 was significantly inhibited by histidine, which may suggest reactive oxygen species plays a primary role in sonodynamically-induced antitumor effect.

Detection and protection of apoptosis, autophagy and neurovascular unit (NVU) are essentially important in understanding and treatment for ischemic stroke patients. In this study, we have conducted an in vivo optical imaging for detecting apoptosis and activation of matrix metalloproteinases (MMPs), then evaluated the protective effect of 2 package types of free radical scavenger edaravone (A and B) on apoptosis, autophagy and NVU in mice after transient middle cerebral artery occlusion (tMCAO). As compared to vehicle treatment, edaravones A and B showed a significant improvement of clinical scores and infarct size at 48 h after 90 min of tMCAO with great reductions of in vivo fluorescent signal for MMPs and early apoptotic annexin V activations. Ex vivo imaging of MMPSense 680 or annexin V-Cy5.5 showed a fluorescent signal, while which was remarkably different between vehicle and edaravone groups, and colocalized with antibody for MMP-9 or annexin V. Edaravone A and B ameliorated the apoptotic neuronal cell death in immunohistochemistry, and activations of MMP-9 and aquaporin 4 with reducing autophagic activations of microtubule-associated protein 1 light chain 3 (LC3) in Western blot. In this study, edaravone in both packages showed a similar strong neuroprotection after cerebral ischemia, which was confirmed with in vivo and ex vivo optical imagings for MMPs and annexin V as well as reducing cerebral infarct, inhibiting apoptotic/autophagic mechanisms, and protecting a part of neurovascular unit.

A series of 5-phenyl-substituted-N-alkyl-imidazolin-2-ones with potent radical-scavenging activity and lipid peroxidation inhibitory activity was synthesized. Many of the compounds showed memory-improving effect in animal models independent of the inhibitory activity on lipid peroxidation.

This paper describes the discovery of a novel free radical scavenger, 3-methyl-1-phenyl-2-pyrazolin-5-one (edaravone, 1), as a potent antioxidant agent against lipid peroxidation. The structure-activity relationship of edaravone indicated that lipophilic substituents were essential to show its lipid peroxidation-inhibitory activity. In vivo studies revealed that edaravone showed brain-protective activity in a transient ischemia model.

Hydrolysis of various nitriles to amides was carried out in aqueous phase over suspended copper catalysts. Cross-linked poly(4-vinylpyridine), magnesia, and silica-magnesia were used as supports. Copper-on-polymer was highly active in comparison with copper powder. In spite of the larger crystallite size, copper-on-magnesia (68 A) was much more active than copper-on-polymer (amorphous) for selective hydrolysis of nicotinonitrile to amide. A cooperative effect of copper and the basic support was suggested. However, weakly acidic silica-magnesia was favorable as support than basic magnesia for hydrolysis of aliphatic nitriles to amides. Selectivity to acrylamide over copper-on-magnesia was as high as 75%, which would be difficult to attain by the alkaline hydrolysis, but the side reaction to cyanohydrin (8%) was not negligible. Copper-on-silicamagnesia resulted in the predominant formation of acrylamide. An 88% conversion of acrylonitrile was obtained in 8 hr at 80 °C with selectivities of 97% to amide and 0.8% to cyanohydrin. Results for propionitrile and benzonitrile are also described. The present catalysts were shown to degenerate on exposure to air. Hydrogen reduction was effective for complete regeneration of the deactivated copper-on-silica-magnesia, while it was unsuccessful for copper-on-polymer. The rate of hydrolysis revealed to deviate from first order kinetics at higher conversions. The kinetic behavior was explained by the product retardation.

The effects of intrahippocampally administered catechol- and indoleamines on the two types of hippocampal seizure discharges elicited by electrical and chemical stimulation were examined in unanesthetized rabbits. The catecholamines norepinephrine (NE) and dopamine (DA), injected into the hippocampus in doses of 100--200 micrograms, inhibited electrically induced hippocampal seizure discharges with a 50% increase in the stimulation threshold. However 5-hydroxytryptamine (5-HT) at doses of 50 micrograms to 100 micrograms caused no effect on electrically induced seizure discharges. On the contrary, 5-HT and 5-hydroxytryptophan (5-HTP) at a dose of 50 micrograms potentiated carbachol (5 micrograms)-induced hippocampal seizure discharges, prolonging the duration of seizure discharge three times the control. NE and DA had no effect on this chemically induced hippocampal discharges. It is therefore suggested that the effects of monoamines on hippocampal seizure discharges are very much dependent on the type of stimulation employed for the induction of this phenomenon.

Using cultured bovine aortic endothelial cells, the effects of MCI-186, a radical scavenger, were studied on arachidonic acid metabolism and on the cell injury caused by 15-HPETE. MCI-186 at 3 X 10(-5) M enhanced prostacyclin production in the intact endothelial cells without affecting phospholipase A2. When endothelial cell homogenates were used as an enzyme source, it was found that MCI-186 stimulated the conversion of arachidonic acid to prostacyclin like phenol, perhaps by trapping OH radicals produced in the process of the conversion of PGG2 to PGH2. On the other hand, MCI-186 was found to inhibit lipoxygenase metabolism of arachidonic acid in cell free homogenates of rat basophilic leukemia cells. The lipoxygenase inhibition caused by 3 X 10(-5) M MCI-186 was almost equivalent to that caused by 3 X 10(-6) M BW 755C. MCI-186 remarkably protected against endothelial cell damage caused by 15-HPETE. 3 X 10(-5) M of 15-HPETE caused endothelial cell death in about 60% of the population: however, pretreatment of the cells with 10(-5) M of MCI-186 or concomitant addition of 10(-5) M of MCI-186 with 15-HPETE to the cultures prevented the cell death completely. These results suggest that MCI-186 may become an unique anti-ischemic drug.

Dehydrative condensation of cyclohexanone and benzophenone with ammonia over thoria prepared from oxalate have been studied.In the case of cyclohexanone, various products such as cyclohexenylcyclohexanone and some nitrogen-containing compounds were obtained at 365-410C while a trace amount of cyclohexanoneimine was detected.Benzophenone condensed selectively with ammonia to form ketimine in high yield at 310v 4200C. Effects of temperature, feed rate, partial pressure of ketone and ammonia are shown in Figs.2-5. Yields of ketimine were reached, for example, 80.5% and 44.0% for O.3X10-2atm and 3.0X10-2 atm of ketone, respectively, in the presence of exess ammonia at 365C. A value of apParent equilibrium constant was estimated to be K=0, 035 0, 002 at 365C.The selective condensation behavior of benzophenone with ammonia was attributed to the lack of a-hydrogen which was necessary to form aldol-type condensation products.

慢性電極植込ウサギを用い，行動観察と同時に脳波を測定し，hydroxyzineの脳波作用をdiazepam，chlorpromazineのそれと比較検討した．1)Hydroxyzine2～5mg/kgの用量ではdiazepam，chlorpromazineと同様に鎮静作用を示すが，10～15mg/kgの大量では投与初期に被刺激性の増大を示した後，鎮静をおこす．脳波は小量投与でも大量投与でも皮質，扁桃核では高電圧徐波化し，海馬覚醒波の同期はくずれdrowsypatternになる．この脳波の変化は大量投与初期に動物が興奮症状を示している時期でも同じであった．Diazepamおよびchlorpormazineは鎮静状態に一致して脳波もdrowsy patternになるがdiazepamの場合は徐波に速波が重畳する点が特徴であった．2)音刺激による脳波覚醒反応はhydroxyzineによって著明に抑制された．Diazepam，chlorpromazineの作用も同様であった．3)中脳網様体，後部視床下部および視床内側中心核刺激による脳波覚醒反応はhydroxyzineおよびdiazepamによってすべて抑制されるが，中脳網様体刺激による脳波覚醒反応だけはchlorpromazineによって抑制されなかった．4)漸増反応(recruitingresponse)はhydroxyzine，chlorpromazineによって軽度に増強され，diazepamではむしろ抑制の傾向を示した．5)閃光刺激によって後頭葉皮質に誘発される電位(photic driving response)はhydroxyzineによって軽度に抑制されたが，diazepam，chlorpromazineではほとんど影響されなかった．6)海馬，扁桃核の刺激による後発射(afterdischarge)はhydroxyzine2～5mg/kgの用量では増強，10～15mg/kgでは逆に抑制された．Diazepamはafterdischargeを著明に抑制し，chlorpromazineは逆にこれを増強した．7)以上，hydroxyzineの脳波作用はdiazepamに類似した点が多いが，大脳辺縁系のafterdischargeに対する作用はむしろchlorpromazineに似たところがあり，てんかんなどのけいれん性疾患またはこれらの既往歴のある患者に対して本剤を用いる場合は慎重な観察のもとに投与することが必要であると考えられる．

We examined the effects of MCI-186 (3-methyl-1-phenyl-2-pyrazolin-5-one), a novel free radical scavenger and an inhibitor of ischemia-induced brain edema, on monoamine metabolism in the brains of both normal and ischemic rats. In normal rats, 3 mg/kg i.v. MCI-186, a dose that prevents ischemic brain edema, had no significant effect on brain concentrations of dopamine, norepinephrine, 5-hydroxytryptamine, or their metabolites. After the injection of 5 microliters of 3% polyvinyl acetate into the left internal carotid artery, concentrations of 3,4-dihydroxyphenylacetic acid and homovanillic acid markedly increased, but that of norepinephrine decreased, in the left telencephalon of embolized rats compared with control rats injected with vehicle; the concentration of 5-hydroxyindoleacetic acid also increased slightly. These effects were maximal 2 hours after embolization. The turnover rate of dopamine between 6 and 8 hours after embolization was significantly higher but that of norepinephrine was slightly lower than that in vehicle-treated rats. When rats were treated with 3 mg/kg i.v. MCI-186 immediately after the injection of polyvinyl acetate, the embolization-induced changes in monoamine metabolism were less marked. Our results suggest that MCI-186 attenuates ischemia-induced changes in brain monoamine metabolism, probably due to its free radical scavenging action, although it has no marked effect in normal rats.

We induced brain edema in 72 rats by injecting 5 microliters of 3.0% wt:vol polyvinyl acetate into the left internal carotid artery, producing permanent embolization in the left cerebral hemisphere, which developed ipsilateral brain edema reproducibly. Edema was assessed 24 hours after embolization by determining the brain water content and the sodium and potassium concentrations. In this model, the free radical scavenger MCI-186 at 1.0 and 3.0 mg/kg i.v. prevented brain edema in a dose-dependent manner. At 3.0 mg/kg i.v., MCI-186 significantly reduced water content by 1.5% and improved the sodium-potassium balance to within the normal range in the embolized left hemisphere. Dexamethasone at 1.0 mg/kg i.v. did but at 3.0 mg/kg i.v. did not significantly inhibit the development of brain edema. Indomethacin at 4.0 mg/kg i.p. had no effect on brain edema. We suggest that the cyclooxygenase metabolites of arachidonic acid liberated from neuronal cell membrane phospholipids are not likely to be involved in the pathogenesis of permanent brain edema induced by polyvinyl acetate. Our results suggest that MCI-186 attenuates brain edema by suppressing the production of lipoxygenase metabolites, including free radicals or lipid peroxides, and that it may prove valuable for the treatment of brain edema associated with cerebral ischemia.

The hypotensive activity of terazosin has been attributed to inhibition of postsynaptic alpha-1 adrenoceptors. The present study examined the influence of terazosin on spontaneous sympathetic outflow in anesthetize and immobilized rats. The effects on blood pressure and heart rate were also evaluated. Intravenously (i.v.) injected terazosin 0.3 mg/kg and prazosin 0.1 mg/kg increased a sympathetic outflow by 15.4 and 21.6%, respectively. These drugs produced a significant and long-lasting fall in blood pressure with slight heart rate change. On the contrary, clonidine 0.1 mg/kg, i.v. significantly inhibited the sympathetic outflow by 69.2%. The intracerebroventricularly administered 10 micrograms/kg clonidine also showed the sympathoinhibitory effect. However 3 micrograms/kg, i.c.v. of terazosin and prazosin increased the sympathetic tone by 16 and 7.2%. During these periods, in both drugs slightly decreased the blood pressure. These changes in hemodynamic parameters and nerve activities were obtained at 2 approximately 3 min after the i.c.v. administration. The 10 micrograms/kg, i.c.v. of terazosin and prazosin significantly inhibited the pressor response by phenylephrine 1 micrograms/kg, i.v. These results indicate the peripheral effect of terazosin and prazosin through the penetration of the drugs from the brain. The results provide evidence that terazosin, like prazosin, dose not affect cardiovascular regulation by a central action.