Proposal of a new mechanism for the directional propagation of the action potential using a mimicking system.

A nerve conduction model is constructed by using some liquid-membrane cells that mimic the function of the K+ and Na+ channels. By imitating two types of Na+ channels (ligand-gated Na+ channels and voltage-gated Na+ channels), a new mechanism for the directional propagation of the action potential along the axon toward the axon terminal is proposed. When the nerve cell is excited by an external (outer) stimulus, it can be presumed that the ligand-gated channels work as power sources at the synapse to propagate the change in the membrane potential, and then the voltage-gated channels locally assist the propagation at each site of the axon (nodes of Ranvier).

Electrode reaction of Pu3+/Pu couple in LiCl-KCl eutectic melts: comparison of the electrode reaction at the surface of liquid Bi with that at a solid Mo electrode.

The electrode reaction of Pu3+/Pu couple at the interface between LiCl-KCl eutectic melt containing PuCl3 and liquid Bi phase was investigated by cyclic voltammetry at 723, 773 and 823 K. For comparison, the system was also studied using a solid Mo electrode in place of the liquid Bi electrode. It was found that the electrode reaction of Pu3+/Pu couple at the Bi electrode was almost reversible. The redox potentials of Pu3+/Pu couple at the liquid Bi electrode in the LiCl-KCl eutectic melt containing 0.87 wt% PuCl3 (0.0014 mole fraction) at 723, 773 and 823 K were observed to be more positive by 0.575, 0.572 and 0.566 V, respectively, than those at the Mo electrode. These differences in potential were thermodynamically analyzed by assuming a lowering of the activity of Pu in Bi phase according to the alloy formation of PuBi2.

[Anosmia or hyposmia after long-term oral administration of tegafur--improved anosmia].

Seventeen patients who manifested anosmia or hyposmia after long-oral administration of Tegafur (FT-207) in postoperative chemotherapy for cancer were followed up. Anosmia improved in 9 of 17 patients (52.9%), and the recovery period was between 3 and 42 months after the manifestation, and between 1 and 35 months after discontinuation of FT-207. Rhinoscopy and radiography revealed no abnormal findings in the nasal septum, rima oflactoria, concha nasalis media, sinus ethmoidales, etc. As it took a long time to recover from these signs and symptoms, they were presumed to be due to reversible neurological anosmia or hyposmia.

[Experimental and clinical studies on the mechanism of alcoholic fatty liver (author's transl)].

In order to clarify the mechanism of alcoholic fatty liver, rats were reared with alcohol diet from adult, foetal or weanling periods. When rats were fed with the diet from adult for 4 weeks, these livers showed apparent fatty deposition histologically and biochemically. Low density lipoprotein (LDL) in serums of these rats lowered in level significantly than control, which indicate decreased production of secretion of very low density lipoprotein (VLDL) in the liver from which converted to LDL in peripheral tissues. When rats were reared with the diet from their foetal life, their livers deposited little of fat at any time examined after birth up to 13 weeks in spite of good diet uptake. The same phenomenon was observed in rats reared from their weanling period with the diet. In situ liver perfusion was performed to clarify the anti-fatty liver mechanism. Ketone body (KB) production rates from palmitate infused constantly at physiological concentration and bile production rates were not different among control, weanling and foetal groups. Oxygen consumption rate in control decreased after infusion of palmitate-albumin complex solution. However the rates in weanling and foetal alcohol rats increased significantly after infusion of the solution. The latter group showed more increase in rate than the former. When theoretical oxygen consumption for production of KB was compared with actual one, livers from control rats seemed to use the whole oxygen for KB production. On the other hand only 59.7% of whole oxygen in foetal alcohol group and 85.9% in weanling group used for KB production respectively. It is surmized that the increased non ketone oxygen in these groups, especially in foetal alcohol group, indicate the anti-fatty liver mechanism in these groups, probably augmented FFA oxidation. Electrophoretic analysis of lipoproteins in chronic alcoholisms showed decreased beta and pre-beta band and increased alpha band. These changes returned to normal after 1 week of admission. These experimental and clinical data indicate that impaired oxidation of FFA is an important factor for the formation of alcoholic fatty liver and impaired transport of fat from liver might enhance the change in the liver.