Effect of increased task procedures on correlation dimensions of the electroencephalogram

Changes in correlation dimensions of the electroencephalogram (EEG) were examined in three different tasks. These three tasks differed from each other with respect to the number of procedures. In the present experiment, left-hand movement and mental arithmetic were controlled, respectively, during an auditory linguistic task. Subjects were 13 healthy right-handed males. EEG signals from eight electrode sites were analyzed and the correlation dimensions were obtained. In addition, the relative power was obtained for the alpha band. An increase in the number of procedures yielded high dimensionality on the occipital EEG. In contrast, left-hand movement had no significant effect on EEG dimensions over the motor area. The relative power of the alpha band was seen to decrease in all channels as the number of procedures increased. The fact that changes in EEG dimensions did not necessarily exhibit a simple correspondence to changes in alpha wave activity was also discussed.     

Melanocyte lysis by cytotoxic T lymphocytes recognizing the MART-1 melanoma antigen in HLA-A2 patients with Vogt Koyanagi Harada disease

The MART-1/Melan-A melanoma antigen recognized by the majorityof HLA-A2-restricted tumorinfiltrating lymphocytes is a selfantigen expressed on melanocytes and the retina. We have investigatedwhether Vogt–Koyanagi–Harada (VKH) disease and sympatheticophthalmia (SO), systemic inflammatory disorders affecting variousorgans containing melanocytes, are autoimmune diseases directedtoward the MART-1 antigen. In two of three patients with VKHdisease and one patient with SO, CD8⁺ T cell clones (TCC) fromintraocular fluid of HLA-A2⁺ patients lysed T2 cells when pulsedwith a HLA-A2-binding MART-1 peptide, but not a HLA-A2-bindingpMel-17 or tyrosinase peptide, in a HLA-A2-restricted manner.These CD8⁺ TCC lysed both melanocytes and melanoma cells ina HLA-A2-restricted manner. In addition, CD8⁺ TCC recognizinga HLA-A2-binding MART-1 peptide were also established from peripheralblood mononuclear cells of a patient with VKH disease. In contrast,either CD4⁺ TCC from these patients or CD8⁺ TCC from the intraocularfluid of HLA-A2⁺ patients with uveitis associated with Behcet'sdisease or HTLV-I uveitis did not show this cytotoxicity. Theresults demonstrate that the MART-1 peptide-specific cytotoxicT lymphocytes lyse melanocytes in the eye of patients with VKHdisease or SO, suggesting that these diseases are autoimmunediseases directed toward the MART-1 antigen in HLA-A2⁺ patients.     

Analysis of three compartments of extracellular fluid in dog

The distribution kinetics of an extracellular volume tracer 51Cr-EDTA was analysed from the results of continuous monitoring of plasma radioactivity. 51Cr-EDTA was injected intravenously into spleno-nephrectomized dogs by a single injection, and the radioactivity of circulating blood and physiological parameters were continuously monitored for 150 min. The dilution curve of radioactivity was resolved into 4 components, and expressed as c(t) = Ae-alpha t + Be-beta t + Ce-gamma t + D. The half-times of each term were 0.51, 2.41, and 19.26 min, respectively. Based on this result, 51Cr-EDTA space was divided into 3 compartments--plasma volume (V0), rapidly diffusing interstitial fluid (V1), and slowly diffusing interstitial fluid (V2). To explain the distribution of the tracer among these fluid spaces, two possible models were proposed. In the "tandem model" the volume of each compartment was calculated as 59.2, 121.7, and 101.7 ml/kg of body weight, respectively, and the mobility index of the tracer from V0 to V1 was 5.1 times as great as that from V1 to V2. In the "parallel model" the volumes were 59.2, 72.3, and 151.1 ml/kg of body weight and the mobility index of the tracer from V0 to V1 was 3.3 times as great as that from V0 to V2. The characteristics of each model were discussed in relation to the properties of the interstitial space.     

Role of N-methyl-D-aspartate receptors and the nitric oxide pathway in nociception/hyperalgesia elicited by protease-activated receptor-2 activation in mice and rats

Activation of the peripheral protease-activated receptor-2 (PAR-2) triggers nociceptive behaviour and thermal hyperalgesia in rats. The present study created a novel mouse model for PAR-2-triggered nociception, and then examined the roles of NMDA receptors and the nitric oxide (NO) pathway in nociceptive processing by PAR-2. Intraplantar administration of the PAR-2 agonist SLIGRL-NH(2) elicited nociceptive responses in mice, an effect being more specific in mast cell-depleted mice. This PAR-2-triggered nociception was abolished by the NMDA receptor antagonist MK-801, but not the neuronal NO synthase inhibitor 7-nitro indazole. In contrast, the PAR-2-triggered thermal hyperalgesia in rats was blocked by both agents. Our study thus provides a novel mouse model for PAR-2-mediated nociception, and suggests that NMDA receptors are involved in PAR-2-triggered nociception and hyperalgesia, while NO contributes only to the latter.     

Polyarteritis Nodosa with Atrophy of the Left Hepatic Lobe

A 73-year-old Japanese man with a history of partial gastrectomy due to gastric cancer 4 years previously was admitted because of intermittent fever. The patient developed abdominal pain, erythema, and myalgia in addition to the fever during the final clinical course, and died of acute heart failure. Autopsy disclosed atrophy of the left lobe of the liver and acute myocardial infarction. Neither metastasis nor recurrence of the cancer was observed. Small and medium-sized arteries of the visceral organs showed various stages of necrotizing vasculitis with narrowing of the lumina. The vasculitis was most prominent in the left lobe of the liver and in the heart. Narrowing of the portal vein due to portal tract inflammation in addition to vasculitis of the hepatic arteries may have induced ischemia and infarction, which had resulted in atrophy of the left hepatic lobe. Acta Pathol Jpn 42: 662–666, 1992.     

Neuronal histamine inhibits methamphetamine-induced locomotor hyperactivity in mice

Mianserin (5-20 mg/kg), like chlordiazepoxide (2.5-10 mg/kg), inhibits the shock-induced suppression of drinking (SSD) in rats. However, in contrast to chlordiazepoxide, the effect of mianserin is not blocked by the benzodiazepine antagonist, Ro 15-1788 (10 mg/kg). Although mianserin does not inhibit [3H]diazepam binding in vitro it has now been found to enhance [3H]flunitrazepam binding to mouse whole brain in vivo at 10-100 mg/kg p.o. These results suggest that mianserin does influence central benzodiazepine receptors, but the mechanism by which it does so differs from that of chlordiazepoxide.     

Interaction of cholecystokinin with vasoactive intestinal peptide in body shaking response to ice-water immersion in rats

Interaction of cholecystokinin (CCK) with vasoactive intestinal peptide (VIP) in body shaking response to ice-water immersion was observed in pentobarbital-anesthetized rats. Although CCK itself had no influence on the response, VIP suppressed it and this effect of VIP was antagonized by simultaneous administration of sulfated octapeptide of CCK, but not by non-sulfated CCK.     

Topographical projections from the thalamus to the putamen in the cat

Thalamic projections to the putamen (Put) in the cat were studied by the retrograde horseradish peroxidase method. Major thalamic projections to the Put originate from the midline and intralaminar nuclear regions including the centre médian-parafascicular complex (CM-Pf). The other thalamic projections to the Put arise mainly from the suprageniculate nucleus (Sg), magnocellular division of the medial geniculate nucleus (MGm), caudomedial part of the lateroposterior nucleus (LP) and ventrolateral part of the ventromedial nucleus (VM). The VM projects to the rostral Put, while the posterior thalamic regions (Sg, MGm, LP) project to the caudal Put.