24 research outputs found
The Linguistic School of Prague
Based on a series of lectures given at Indiana University in 1964, The Linguistic School of Prague discusses the famed Prague Linguistic Circle and its work. The book was originally described on its original 1966 cover flap as follows: "In this volume … Josef Vachek, one of the original members of the famed [Prague Linguistic] Circle, traces its prehistory adn the general linguistic context in which the Circle came into existence. He also provides an illuminating account of the sepecific Prague conception of language as a system of systems in motion—a dynamic structure—and illustrates how the Prague approach differs from those of the Cophanhagen and Yale linguistic groups. In succeeding chapters, Professor Vachek discusses in detail the analysis of the phonic level—both synchronic and diachronic—and main problems of morphonology and morphology, as well as of grammar and style. Special attention is given to the historical development of language, … [and] in conclusion the author relates the Prague approach to that of present-day mathematical and applied linguistics, whose adherents have admittedly drawn some inspiration from the Prague ideas of the thirties.
Effect of Methoxime Combined with Anticholinergic, Anticonvulsant or Anti-HCN Drugs in Tabun-Poisoned Mice
The effect of methoxime combined with a) atropine, b) benactyzine, c) atropine and natrium thiosulphate, d) atropine and diazepam on antidotal treatment effectiveness was studied in tabun-poisoned mice. In addition, the influence of pretreatment consisiting of pyridostigmine, benactyzine and trihexyphenidyle (PANPAL) administered 2 hours before tabun intoxication on the treatment effectivity of methoxime combined with e) atropine or f) benactyzine was tested. The most efficacious therapeutic mixture in non-pretreated mice was methoxime, atropine and diazepam. Natrium thiosulphate did not significantly increase neither decrease the antidotal treatment efficacy in comparison with methoxime and atropine alone. Pretreatment with PANPAL significantly decreased tabun toxicity (nearly 4 times in methoxime and benactyzine combination and more than 4 times in atropine and methoxime mixture). The present study demonstrates that the tabun toxicity in mice is more effectively reduced when PANPAL prophylactically is administered than in case of treatment with methoxime and cholinergic drug alone. We established that anticholinergic drug option in the therapeutic mixture of methoxime and anticholinergic drug did not cause the difference in the antidotal treatment effectivities
The Impairment of Spatial Memory Following Low-Level Sarin Inhalation Exposure and Antidotal Treatment in Rats
1. To study the influence of antidotes on low-level sarin-induced impairment of cognitive functions, the rats were exposed to three various low concentrations of sarin (LEVEL 1–3) for 60 minutes in the inhalation chamber. In addition, one group of rats was exposed to LEVEL 2 of sarin repeatedly. 2. Testing of cognitive functions was carried out using the Y-maze evaluating learning and spatial memory. The correct averse behavior of sarin-exposed rats in the Y-maze was tested several times within four weeks following sarin inhalation exposure and antidotal treatment to look for any cognitive impairments. 3. The results were compared to the Y-maze performance of sarin-exposed rats without antidotal treatment and control rats exposed to pure air instead of sarin with or without antidotal treatment. While antidotal treatment was able to eliminate a short-term deficiency in the Y-maze performance in rats exposed to the LEVEL 1 of sarin, a significant decrease in the Y-maze performance in rats exposed to sarin at the LEVEL 2 and 3 was only shortened. Sarin-induced spatial memory impairments in rats exposed repeatedly to sarin at the LEVEL 2 was also shortened when rats were treated following each sarin inhalation exposure. 4. The findings confirm that antidotes currently used for nerve agent poisonings are beneficial for the treatment of rats singly or repeatedly exposed to non-convulsive symptomatic or even clinically asymptomatic concentrations of sarin
Inhalation Apparatus for Generating Sarin and Soman Toxic Vapors
The developed inhalation system is a dynamic and whole-body exposure model designated for generating sarin or soman vapors. It consists of an evaporating apparatus, an inhalation chamber and a carbon filter. The inhalation chamber is made of stainless steel and its total volume is 36 l. The concentration of organophosphorus compound depends on airflow through the chamber, syringe volume of the dosing pump and dosing speed. For determination of organophosphorus compound (OPC) concentration, a modification of Ellman method is used. At generating of vapors in the inhalation chamber the means of the yield were 61.4 ± 6.6 % for sarin and 35.8 ± 3.5 % for soman. The better yield for sarin than for soman, because of the higher volatility of sarin in comparison with soman was achieved. The stable concentration of the OPC for several hours could be maintained in the inhalation chamber when only relatively small amount of the OPC is used. Using the developed inhalation system LCt50 for sarin and for soman in rats was determined. At 1 h exposure the LCt50 values were 4.72 mg.h-1.m-3 for sarin and 4.81 mg.h-1.m-3 for soman. The results presented show that the inhalation chamber successfully fulfils the role of instrument for inhalation intoxication of small laboratory animals with highly toxic OPC
Effect of Atropine and the Oxime HI-6 on Low-Level Sarin-Induced Alteration of Performance of Rats in a T-Maze
1. To study the influence of antidotes on low-level sarin-induced alteration of cognitive functions, male albino Wistar rats were exposed to three various low concentrations of sarin for 60 minutes in the inhalation chamber. One minute following sarin exposure, the rats were i.m. treated with the oxime HI-6 in combination with atropine. Control rats were treated with antidotes as experimental rats but exposed to the pure air instead of sarin. Cognitive functions of the rats were tested using a T-maze where spatial memory and spatial orientation were evaluated. The performance of sarin-exposed and treated rats in the T-maze was tested several times within six weeks (single exposure) or five weeks (repeated exposure) following inhalation exposure to evaluate cognitive impairments. 2. In the case of single exposure to sarin, no statistically significant differencies between the performances of the control and the experimental groups in the alteration of spatial memory and spatial orientation were observed. The repeated exposure of treated rats to clinically asymptomatic dose of sarin (LEVEL 2) did not change the effect of low-level sarin exposure on spatial memory of the experimental rats compared to the single exposure to the same dose of sarin. 3. The decrease in the T-maze performance of the control rats was caused by the impairments of rat’s mobility due to the features of a solution of antidotes