Syntaxin 1A/HPC-1 and syntaxin 1B, neuronal membrane proteins, belong to the syntaxin family, members of which are closely related to functions in the intracellular membrane trafficking mechanism. However, physiological roles of these two isoforms of syntaxin 1 in the mammalian central synapse have not been examined separately. To clarify specific functions of syntaxin 1A/HPC-1 and syntaxin 1B, I have undertaken to investigate the effects of specific antibodies against syntaxin 1A/HPC-1 and syntaxin 1B on the central synaptic transmission of the rat hippocampal neurons. To investigate the effects of the antibody on central synaptic transmission, an autapse, a synapse made by the central neuron on itself in micro-island culture provides an useful experimental system, since antibody is easily applied intracellularl-y to the cell soma through a recording whole-cell patch-pipette. Results demonstrated that a specific antibody against syntaxin 1A/HPC-1 or syntaxin 1B increased the amplitude of the autaptic excitatory postsynaptic current (EPSC), while each antibody did not change the quantal size, a measure of sensitivity of post synaptic receptors, estimated from the amplitude distribution pattern of the asynchronous EPSC. Thus, each antibody was strongly suggested to increase the synaptic exocytosis from the presynaptic terminals. Results suggested that both syntaxin 1A/HPC-1 and syntaxin 1B are cooperatively involved in some inhibitory mechanisms for Ca-dependent exocytosis in the mammalian central synapse.

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Changes in the unsaturation degree of the hepatic lipids was determined in partially hepatectomized rats by ^1H-NMR spectrometry, along with the changes in fatty acid composition in the liver lipid, lipoperoxide contents, and vitamin E levels in the liver. On day 1 after partial hepatectomy, the content of mono- or dienoic fatty acids such as oleic (18:1(n-9)) or linoleic acid (18:2(n-6)) increased, while polyunsaturated fatty acids (PUFA) composition such as arachidonic (20:4(n-6)) or docosahexaenoic acid (22:6(n-3), DHA) decreased in the regenerating liver. But ^1H-NMR spectroscopic analyses revealed no significant change in the unsaturation degree in hepatic lipids at that time. The degree of lipid unsaturation increased to a maximal level on day 5 after hepatectomy, much attributable to the relative increase in DHA (22:6(n-3)). Hepatic lipoperoxide contents greatly increased around 22 hours after hepatectomy. On the contrary, hepatic vitamin E levels decreased during the early phase of the regeneration. On day 5 to 7 after hepatectomy, when the lipid unsaturation degree increased, lipid peroxidation did not show any increase and hepatic vitamin E remained in a lower level than that of untreated control rats. Vitamin E might be consumed to suppress lipid peroxidation during these periods. The high level of hepatic lipoperoxides during the early phase of the regeneration might be caused by the breakdown of PUFA. These results suggest that lipid peroxidation is one of the essential factors for the initiation of liver regeneration. The increased lipid unsaturation level on day 5 would appear to be an inhibitory signal for the liver regeneration, and DHA (22 : 6(n-3)) seems to be involved in a switch on/off mechanism of the cell proliferation.

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Experimental procedures were analyzed for the QPCR method by which the amount of cDNA, the product of reverse transcriptase reaction of mRNA, could be determined in a high sensitivity to estimate the expression level of a gene. RNA extracted from mouse liver, was first converted to cDNA by the action of reverse transcriptase. Thus obtained cDNA was further amplified by PCR with a set of primers for p53 gene, one of which was labeled with chemoluminescence inducible material, TBR (tris (2,2-bipyridine) ruthenium (II) chelate), and the other with biotin. The PCR products coupled to streptavidine-conjugated magnetic beads, led into the QPCR device and electrochemical luminescence induced from TBR was measured. In 30 times of the amplification the luminosity was approximately proportional to the amount of RNA between 0.01 to 0.25μg added to the assay mixture. In 20 to 25 times of the PCR cycle, RNA in the range of 0.1 to 1.0 μg was correlated with the luminosity. With this method, a minimum of 1.0×10^<-16> moles of cDNA was able to be determined with 13〜14 % of Coefficient of Variation within 3 hours. DNA contaminated in the RNA material by 5 % apparently exhibited no interference on the chemoluminescence production but by 10 % in the material decreased the luminosity to 90 % of the original one. RNA preparation treated with DNase to eliminate the contaminated DNA strongly decreased the luminosity.

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RNase E which was initially discovered as a ribosomal RNA processing enzyme in E. coli, has since been found to have a central role in the degradation of a variety of mRNA. Therefore, in order to understand better the decay process of mRNA, it is important to determine RNase E cleavage sites of individual RNA. Determination of RNase E cleavage sites was performed in a cell-free system using radiolabeled RNA transcribed in vitro by T7 RNA polymerase as a substrate for purified RNase E. In this study, using fluorescent dye labeled 9S RNA, site-specific cleavages of 9S RNA by RNase E were analyzed by a fluorescence bioimage analyzer. It was found that fluorescent labeling method is a useful and safety non-radio active method although it's sensitivity is several times lower than that of radio- labeling method.

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In the years 1991-1996, we serodiagnosed 3,162 patients suspected as parasitic infections, especially, helminthic infections. The total numbers of positive sera were 854 out of 3,162 samples (27.0 %) ; 487 against Toxocara canis antigens (Ag) (57.0%), 103 against Anisakis spp. Ag (12.1 %), 82 against Paragonimus spp. Ag (P. westermani and P. miyazakii 9.6%), 37 against Fasciola hepatica Ag (4.7%), 35 against Angiostrongylus cantonensis Ag (4.1 %), 27 against Ascaris lumbricoides Ag (3.2 %) and 25 against Schistosoma spp. Ag (S. japonicum and S. mansoni 2.9%). In addition, the positive sera against Gnathostoma spp., Ancylostoma caninum, Clonorchis sinensis and Diphyllobothrium nihonkaiense Ag were less than 1%. The age of patients showing positive against T. canis Ag showed normal distribution and the peak age was 41-50 years old. Middle age tended to show positive results rather than young age.

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Near-death experience (NDE) was studied in a series of 48 consecutive patients who were admitted to hospital in a deep coma due to life threatening disease. Of 48 patients interviewed, 14 (37%) had a vivid and undeniably personal experience. Among the NDE reported, there were such elements as flying in a dark void space with dim light ahead, encountering dead relatives or friends, standing at the boundary of brook, river or pond, and returning to the world in response to a voice calling from behind. These elements are common to those reported by investigators abroad, except for the lack of a tunnel experience. As for the influence of the NDE on life subsequent to the experience, the majority of patients who had had a NDE stated that they became more sincere towards every aspect of life and held spiritual values in high esteem than before. However, they didn't speak the elements of their experiences to their family or friends, because of feeling NDE was not understood enough. From this study, NDE was thought to be useful to elderly patients in terminal stage by the following points ; 1) the patients recovered from coma are supported by NDE, 2) anxieties or fears in the patients with terminal states are reduced by NDE, 3) young doctors and nurses who had never faced with death are able to get information for death, 4) NDE will be developed to science and medicine.

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We experienced 7 autopsy cases of child abuse, 3 cases of battered child syndrome and 4 cases of single trauma homicide, in our laboratory in the period from 1987 to 1996. The 7 children's mean age was 3 years and 0 months, and sexuality of children were 4 cases in males and 3 cases in females. As for the assailant, the adoptive father was 3 cases, real father was 2 cases, real mother was 1 case and the real mother and adoptive father was 1 case. All 7 cases were killed by physical abuse and the cause of death was head injury in five cases. There was no case of neglect and sexual abuse which reports have remarkably increased in U. S. There were 4 cases of single trauma homicide and 3 cases of battered child syndrome. However, there were not chronic subdural hematoma with multiple fractures of the long bone as the classic pattern of "battered child syndrome" in our cases of battered child syndrome but those cases had been battered for a long time. There was no difference between single trauma homicide cases and battered child syndrome cases in judicial decision. To administer justice on a full understanding of what kind of abuse the child was given, we should have an expert opinion which is able to clearly distinguish between single trauma homicide cases and battered child syndrome cases from the medico-legal autopsy. In Japan, there is a law which saves the rights of children called "JIDO-FUKUSHI-HO". We have such the law, but the child abuse tends to hide in the home and therefore, it is difficult that the person who is except the family discovers an abuse of child. Finally, we proposed that the medical organization and the administrative system should make more effort for the preliminary prevention and the discovery in the early stage of the child abuse to save the lives of the children.

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