Effects of (S)-alpha-fluoromethylhistidine and (R)-alpha-methylhistamine on locomotion of W/Wv mice

We studied the effects of inactivators of the central histaminergic neuron system, (R)-alpha-methylhistamine, a histamine H3 receptor agonist, and (S)-alpha-fluoromethylhistidine, a histamine synthesis inhibitor, on locomotor activity and brain histamine content of mast cell-deficient W/Wv mice using a recently developed high-performance liquid chromatography system coupled with a fluorometric detector. IP injection of (R)-alpha-methylhistamine (6-50 mg/kg) increased brain histamine content after 1 h but caused no significant change in locomotor activity. IP injection of (S)-alpha-fluoromethylhistidine decreased brain histamine content at doses of 6-50 mg/kg and locomotor activity at doses of 12.5-50 mg/kg. However, locomotor activity was decreased significantly (in Student's t-test) by sequential administrations of (S)-alpha-fluoromethylhistidine (6 mg/kg) and (R)-alpha-methylhistamine (12.5 or 25 mg/kg), but not by (S)-alpha-fluoromethylhistidine (6 mg/kg) and other doses of (R)-alpha-methylhistamine (6 or 50 mg/kg). These results support the hypothesis that the central histaminergic neuron system is involved in the control of spontaneous locomotion or alertness.     

High-pressure phase diagram of an aluminium-rich Al-Li alloy at a pressure of 5.4 GPa

The high-pressure phase diagram of an aluminium-rich Al-Li alloy at a 5.4 GPa pressure was investigated. To determine the equilibrium state under high-pressure and high-temperature conditions, the quenching method was applied and a phase analysis of the sample was performed using X-ray diffraction and microscopic observations. The experimental results were then compared with a thermodynamic theoretical calculation and good agreement was found. The resultant solid solubility of lithium in aluminium was subsequently increased up to 20 at % and the eutectic temperature increased up to 800 °C.     

奥氏体动态再结晶组织对马氏体相变的影响

采用电阻测量和Ｘ射线衍射分析方法，研究了Ｆｅ－３２Ｎｉ合金高温变形奥氏体动态再结晶组织对马氏体相变开始温度Ｍｓ点和一定深冷处理温度下马氏体生成量的影响。与静态再结晶组织相比，动态再结晶晶粒组织不均匀，其位错亚结构也不均匀。具有位错密度梯度分布的成长中的动态再结晶晶粒晶界附近含有少量的易移动位错，促进马氏体的形核，提高Ｍｓ点及其Ｍｓ点以下较高温度区域墨迹初期的马氏体生成量，但是对于较低温度区域转变后     

Spot-size converted 1.3 μm laser with butt-jointed selectivelygrown vertically tapered waveguide

A 1.3 μm laser has been developed with a butt-jointed selectively grown spot-sire converter (SSC). The SSC vertically tapered waveguide and strained multiquantum well (MQW) active region are independently optimised. The laser was buried with semi-insulating InP to reduce optical loss in the SSC. A threshold current of 7 mA and an output power of >20 mW were obtained. Minimum coupling loss to a flat-end fibre of 1.06 dB was achieved. Long-term stability was also confirmed     

Heavy metal concentrations in urban snow as an indicator of air pollution

Manganese, Zn, Pb, Cu, Cr and Cd concentrations in snow collected in and around urban areas and from snow dumping stations in Hokkaido were determined by Zeeman-type atomic absorption spectrophotometry. We compared the heavy metal concentrations in the snow with background levels to see whether they could be used as an effective indicator of urban air pollution. The heavy metal concentrations in the snow clearly increased towards the center of the city of Sapporo; they were influenced by local pollution in the industrial area of the city and by the effect of the seasonal wind from the northwest. In the cities, we found the greatest influence on heavy metal concentrations was air pollution caused by industrial activities. The elemental concentrations in urban snow were from several to tens of times higher than background levels. The mean concentrations of the elements studied were in the order Mn greater than Zn greater than Pb greater than Cu greater than Cr greater than Cd, the same as in water except for Pb. We propose that data on trace metal concentrations in snow are a reliable guide to the degree of air pollution, and can be used as a simple and effective indicator of urban air pollution.     

Inhibition of oxidation of low density lipoprotein by troglitazone

The effect of a new oral hypoglycemic agent troglitazone, (+/-)-5-[4-(6-hydroxy-2,5,7,8-tetramethylchroman-2-yl-methoxy)benz yl]-2,4-thiazolidinedione as an antioxidant against the free radical-mediated oxidation of low density lipoprotein (LDL) was studied. The oxidation of LDL gives cholesteryl ester hydroperoxide and phosphatidylcholine hydroperoxide as major primary products. Troglitazone incorporated exogenously into LDL inhibited the oxidations of LDL induced by either aqueous or lipophilic peroxyl radicals and suppressed the formation of lipid hydroperoxides efficiently. Ascorbic acid added into the aqueous phase spared both endogenous alpha-tocopherol and troglitazone in LDL. It was also found by absorption spectroscopic and electron spin resonance (ESR) studies that troglitazone reacted rapidly with a galvinoxyl radical to give a chromanoxyl radical which gives the same ESR spectrum as alpha-tocopherol. This ESR spectrum disappeared rapidly when ascorbic acid was added into the system. These results show that troglitazone acts as a potent antioxidant and protects LDL from oxidative modification.     

Production of thick and highly uniform CD2 targets for measurements

Thick deuterated polyethylene (CD₂) targets were produced by heating and pressing the CD₂ powder. The thickness of the CD₂ targets are from 24 to 560 mg/cm². The uniformity of the target thickness is ±20 μm (2.2 mg/cm²). These targets were used as deuteron targets in the measurement of the elastic scattering at .     

Monitoring serum tryptic activity and effect of trypsin inhibitor on rat acute pancreatitis

The effect of a novel synthetic trypsin inhibitor, 4-(2-succinimidoethylthio)-phenyl 4-guanidinobenzoate methanesulfonate (E3123), on severe acute pancreatitis was studied in trypsin-taurocholate-induced acute experimental pancreatitis in rats. Rats were divided into four groups according to difference of subdivided doses of E3123 with fixing the total dose at 3 mg/kg body weight. Group A: 1.5 mg/kg of E3123 subcutaneously (SC) each at 1 h before and after induction of pancreatitis. Group B: 1 mg/kg SC each at 1 h before, 1 and 3 h after induction. Group C: 1.5 mg/kg SC each at 1 and 3 h after induction. Group D: 1.5 mg/kg SC each at 3 and 5 h after induction of pancreatitis. The survival rate at 24 h was significantly improved in group B (77% in group B, vs. 36% in paired control; p < 0.01) and in group C (70 vs. 38%; p < 0.05), but not in group A or D. Residual tryptic activity of serum alpha 2-macroglobulin trypsin complex (alpha 2M-TRY) was reduced after the injection of E3123 though immunoreactive trypsin remained unchanged in the early phase of pancreatitis. The reduction of alpha 2M-TRY reflected the inhibitory capacity of E3123 in plasma. E3123 showed favorable effects on the initial stage of severe acute pancreatitis and the effects were probably based on the inhibition of alpha 2M-TRY activity in serum.