Analysis of EEG Changes between the Frontal and Occipital Cortex during Speech

Abstract: A method of spatiotemporal analysis, using time series analysis techniques to represent activity in multiple brain regions, was applied to the interpretation of EEG information changes between the frontal and occipital areas during speech. This paper proposes and discusses a bidirectional communication model between the frontal and occipital cortices. Entropy analysis was introduced and used to simplify the calculation of transinformation in two dimensions. In this work, transinformation with direction between the frontal and occipital cortices before and during speech was investigated quantitatively for 11 subjects. The dominant information flow in the occipital-frontal direction was found immediately before speech in the right hemisphere. During speech, the dominant information flow was found in the occipital-frontal direction in both the right and left hemispheres. These results suggest that the method used in our work is feasible to analyze EEG signals in language processes.     

Anticonvulsive effect of dapsone (4,4′-diaminodiphenyl sulfone) on amygdala-kindled seizures in rats and cats

Dapsone (4,4′-diaminodiphenyl sulfone; DDS), an established anti-leprosy drug, showed anticonvulsive effects in the amygdaloid kindling model of epilepsy. Single doses of the drug in rats (6.25–12.5 mg/kg i.p.) suppressed the kindled seizures in a dose-dependent manner without overt behavioral toxicity. With repeated oral administration in cats, relatively higher initial doses (13–23 mg/kg) were required to obtain seizure suppression, and neurotoxic signs occurred within a few days with serum drug levels of approximately 20 μg/ml. Although dapsone showed anticonvulsive effects in both animal species, the effective serum levels overlapped the toxic levels reported in the clinical treatment of leprosy. In the majority of the cats, however, seizure suppression was maintained even after the discontinuation of dapsone with lower serum levels than those observed at the beginning of the seizure suppression. Therefore, dapsone would be useful as an antiepileptic drug only when long-term anticonvulsive efficacy is demonstrated using smaller doses comparable to those used in the treatment of leprosy.     

Effect of three novel K+ channel openers, cromakalim, pinacidil and nicorandil on allergic reaction and experimental asthma.

The anti-allergic and anti-asthmatic activities of three potassium (K+) channel openers, cromakalim, pinacidil, and nicorandil, were investigated. 1) Forty-eight-hour homologous passive cutaneous anaphylaxis (PCA) in mice was not affected by cromakalim, pinacidil, or nicorandil. Ketotifen significantly inhibited the reaction. 2) Antigen-induced histamine release from sensitized guinea pig lung tissue was not affected by cromakalim, pinacidil or nicorandil (except for 10(-4) M nicorandil). Salbutamol inhibited the release of histamine. 3) Histamine, serotonin and LTC4-induced vasculitis in rat back skin was not affected by any of these three K+ channel openers. 4) Antigen-induced constriction of isolated sensitized guinea pig tracheal muscle was relaxed by each of the K+ channel openers. 5) Constrictions of isolated guinea pig tracheal muscle caused by high potassium, histamine, LTC4, or U-46619 were clearly relaxed by each of the three K+ channel openers. 6) Increases of airway resistance caused by histamine, LTD4, or U-46619 in guinea pigs in vivo were inhibited by administration of each of the three K+ channel openers. 7) Experimental asthma caused by the IgE antibody and antigen system in guinea pigs was inhibited by each of the three K+ channel openers.     

An immunoreactive xanthine oxidase protein-possessing xanthinuria and her family.

The presence of immunoreactive xanthine oxidase protein was proven in a xanthinuric patient, using a polyclonal antibody against xanthine oxidase. The antibody was raised against purified human liver xanthine oxidase in a rabbit. Double immunodiffusion method demonstrated the existence of an immunologically reactive xanthine oxidase which did not possess xanthine oxidase activity. In addition, urinary excretion of oxypurines in the patient and her family was investigated. The results indicated that a brother and a sister had xanthinuria.     

In vitro and in vivo activities of sparfloxacin and reference drugs againstChlamydia pneumoniae

The activities of sparfloxacin and reference drugs againstChlamydia pneumoniae were compared by using in vitro and in vivo methods. The minimum inhibitory concentration (MIC) (μg/ml) ranges of sparfloxacin, levofloxacin, tosufloxacin, grepafloxacin, AM-1155, DU-6859a, clarithromycin, azithromycin, and minocycline for sixC. pneumoniae strains (two standard and four clinical strains) were 0.031 to 0.063, 0.25 to 0.5, 0.063 to 0.125, 0.063 to 0.125, 0.063 to 0.125, 0.031 to 0.063, 0.016 to 0.031, 0.125 to 0.25, and 0.016 to 0.031, respectively. The in vitro potency of sparfloxacin againstC. pneumoniae was similar to that of clarithromycin, minocycline, and DU-6859a, and higher than that of the other fluoroquinolones and azithromycin. Fatal pneumonia was induced in cyclophosphamide-treated leukopenic mice by intranasal inoculation withC. pneumoniae KKpn-2. Infiltration of the lung by neutrophils and lymphocytes was confirmed by histopathologic examination. Oral treatment with the various antichlamydial agents was given for seven days; sparfloxacin and minocycline had the lowest ED₅₀ (effective treatment dose in 50% of the mice; given as mg/kg per dose) (1.11 each), followed by DU-6859a (1.92), tosufloxacin (2.09), grepafloxacin (2.41), clarithromycin and azithromycin (2.48 each), AM-1155 (2.77), and levofloxacin (>10). These results suggest that sparfloxacin may be an effective agent forC. pneumoniae infection in humans.