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  Background & Objectives : Cortical spreading depression (SD), a self-propagating depolarization of neuroglial cells, is believed to play a role in different neurological disorders including epilepsy and migraine aura. A brief period of excitation heralds SD which is immediately followed by nerve cell depression and later by prolonged excitation. The aim of the present study was to investigate relationship between SD and late phase of excitability and seizure burst activity inlateral amygdale of rat.

  Methods: Male Wistar rats with 250-350 gram body weight were used. We usedamygdale slices taken from Wistar rats. SD was induced by KCl. After superfusion of these slices with sub-epileptic concentration of bicuculline for 45 min, the induction of SD in the lateral amygdale resulted in presence of interictal and ictalepileptiform field potentials.

  Results: After initiation of SD in lateral amygdale, glutamate receptors (NMDA, AMPA) antagonists as well as K⁺ and Ca⁺⁺ channels blockers were able to decrease the amplitude of excitatory postsynaptic potentials.

  Conclusion: The results imply a possible role for SD in temporal lobe epilepsy in predisposed neural tissue with increased excitation or decreased inhibition. The study of the late phase of SD excitability may help us to understand the mechanism of SD action in associated neurological disorders. This finding may improve the therapeutic strategies for treatment of epilepsy.

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Background & objectives: The purpose of this study was to determine the bacterial bioaerosols in indoor air of Ardabil universities and to investigate the factors affecting their concentration in Ardabil city.
Methods: Air sampling was performed using Andersen single-stage sampler at a flow rate of 28.3 liters per minute and a respiratory range of 10 min. In this study, trypticase soy agar containing cycloheximide antibiotic was used for bacterial culture. Biochemical tests such as DNase, catalase, oxidase, coagulase, bile esculin hydrolysis test, urease, citrate test, antibiotic resistance to novobiocin, bacitracin and optochin were used for identification and differentiation of isolates.
Result: The mean bacterial concentration in Ardabil university of medical sciences in the open air, outside the college, the halls, the classrooms and the staff rooms  was 18, 88.4, 76.6, 77.4 CFU/m³ , respectively. The concentration of bacteria in Islamic Azad university of Ardabil in the open air, outside the college, the halls, the classrooms and the staff rooms was 103, 97, 124, 132 CFU/m³, respectively. The dominant species of bacteria in indoor air were Staphylococcus aureus, Staphylococcus epidermidis, Actinomycetes and Bacillus, respectively.
Conclusion: According to the results of this study, it is found that the concentration of bacterial bioaerosols in indoor air is not more than standard, but the abundance of bacterial species can cause lung, intestinal and other diseases in academic personnel, staff and students in the long-term.