A 'long-term-potentiation-like' facilitation of hippocampal synaptic transmission induced by the nootropic nefiracetam

Nefiracetam, a nootropic agent, enhanced the slope of field excitatory postsynaptic potentials in the CA1 region of rat hippocampal slices to about 170% of basal levels, being evident still at 4-h washing-out of the drug. A similar sustained enhancement (>/=16 h after i.m. injection with nefiracetam) was observed in the population spikes recorded from the granular cell layer of the intact mouse hippocampus. Saturation of the enhancement in the synaptic strength occluded potentiation obtained with long-term potentiation (LTP) induced by high-frequency (tetanic) stimulation, and vice versa. Interestingly, the facilitatory action of nefiracetam was blocked by either the nicotinic acetylcholine (ACh) receptor antagonists, alpha-bungarotoxin and mecamylamine, or the selective protein kinase C (PKC) inhibitor, GF109203X, but in contrast, it was not affected by D-2-amino-5-phosphonovaleric acid (APV), a selective N-methyl-D-aspartate (NMDA) receptor antagonist. The results of the present study suggest that nefiracetam, whereas the action is independent of NMDA receptors, induces an 'LTP-like' facilitation of hippocampal synaptic transmission as a consequence of modulation of nicotinic ACh receptors and PKC. This may represent a likely mechanism underlying the cognition-enhancing actions of nefiracetam.     

Immunocytochemical localization of aromaticl-amino acid decarboxylase and catechol-O-methyltransferase in blood vessel wall of the human dental pulp

Relatively large amounts of DOPA as compared with the concentration of norepinephrine are found in human dental pulp. AADC and COMT are localized in blood vessel walls of human dental pulp. This localization suggests a functional relationship between COMT and AADC with regard to the metabolism of DOPA.     

The mechanism of the inhibitory effect of protease inhibitors on platelet aggregation and cellular synthesis of prostaglandins. I. The effect on the release of arachidonic acid from phospholipids

The inhibitory effect of proteinase inhibitors on platelet aggregation was investigated. The proteinase inhibitors tested were SBTI, leupeptin and FOY (a synthetic proteinase inhibitor). Also, synthetic substrates for serine proteinases (TLME, ATEE) were tested. They completely inhibited the secondary aggregation of platelets induced by ADP or epinephrine. They also completely inhibited the platelet aggregation induced by collagen or thrombin. The aggregation induced by arachidonic acid was completely inhibited by all the proteinase inhibitors and synthetic substrates. The aggregation induced by Ca ionophore A 23187 was completely inhibited by leupeptin, FOY, TLME or ATEE but not by SBTI. It is generally accepted that platelet prostaglandin metabolism plays an important role in platelet aggregation. As the first step to elucidate the possible mechanism of the inhibitory effect of the proteinase inhibitors, their effect on the release of arachidonic acid from platelet phospholipids was investigated. The release of arachidonic acid from ¹⁴C-arachidonate incorporated gel filtered platelets (¹⁴C-AA-GFP) by thrombin or A 23187 was directly measured in the presence or absence of a proteinase inhibitor or synthetic substrate, utilizing thin layer chromatography (TLC) and a scintillation counting. The release was almost completely blocked when the aggregation of ¹⁴C-AA-GFP by thrombin or A 23187 was completely inhibited by a proteinase inhibitor or a synthetic substrate.     

Quality of life (QOL) and nutrition

We thought that nutritional parameters in laboratory data might be able to express quality of life (QOL). Therefore, in 70 patients with malignant chest diseases (NSCLC, 42 patients; SCLC, 15; lung metastasis, 7; others, 6), the correlation between nutritional parameters of total protein (Tp), serum albumin (Alb), and serum (cholinesterase (ChE] and Karnofsky Performance Status scale (KPS) was investigated. Then, in 24 patients with them (NSCLC, 12; SCLC, 6; lung metastasis, 4; others 2), Alb and ChE were compared to the EORTC Core Quality of Life Questionnaire and Lung Cancer-Specific Questionnaire Module (QS). Results were as follows: 1) KPS and nutritional parameters correlated (Tp. r = 0.55, p less than 0.001; Alb, r = 0.60, p less than 0.001, ChE, r = 0.60; p less than 0.001). 2) The cores for Functional Status (FS) and Disease and Treatment-related symptoms (Sym) in QS and parameters of Alb and ChE correlate (FS v.s. Alb, p less than 0.01; Sym v.s. Alb, p less than 0.01; FS v.s. ChE, p less than 0.05; and Sym v.s. ChE, p less than 0.05). Moreover, the scores of Psychological Distress in QS and Alb showed a correlation (p less than 0.05). It is considered that nutrition and part of QOL (KPS and FS + Sym in QS, that is to say, "objective" functional activity and "subjective" functional activity and symptoms) correlate, and that nutritional parameters are useful to evaluate QOL.     

Psychological changes of Japan Self-Defense Forces personnel during selection and training for the peacekeeping mission in the Golan Heights

We sought to determine whether a selection process for deployment had a measurable effect on psychological symptoms by comparing scores on the Yatabe-Guilford Personality Index, the Manifest Anxiety Scale, and the 30-item version of the General Health Questionnaire between deployed and nondeployed mission candidates from the Japan Self-Defense Forces. The studies were undertaken in Japan during education and training for the United Nations peacekeeping mission in the Golan Heights. The participants included 80 candidates for deployment. Personnel who were not deployed had significantly higher measures of manifest anxiety and general psychological distress than deployed personnel, whereas deployed personnel showed more symptoms suggesting somatization. The selection process and training for deployment appear to have been stressful for all personnel, whether deployed or not.