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This experiment tested the reactivity of the cationic surfactant Resamin AE [N-(2-hydroxyethyl)-N-(2-hydroxy-4-oxa(C14÷22-alkyl))-N,N-dimethylammonium chloride] with organophosphonate soman. It was confirmed that soman is incorporated in the micelle of Resamin AE and that the hydroxyl group or Resamin AE supports the hydrolysis of this organophosphonate. A further increase in reactivity was achieved by the addition of hydrogen peroxide into the reaction mixture. In contrast, if the concentration of neutral salts was increased, a decrease in the velocity of the hydrolysis was obtained. The hydrolytic efficacy of Resamin AE was also compared with that of hexadecyldimethyl- (2-hydroxyethyl)-ammonium bromide. Resamin AE appeared to be a more efficacious hydrolytic agent than other similar compounds due to its advantageous chemical structure. [ABSTRACT FROM AUTHOR]

In this work in vitro evaluation of the reactivation potency of the newly synthesized reactivators for acetylcholinesterase (AChE; EC 3.1.1.7) is described. Using this method, reactivation potency of 21 potential reactivators of AChE inhibited by the nerve agent sarin has been evaluated. We have confirmed the fact that currently the most promising AChE reactivator, HI-6, is the most effective reactivator of sarin-inhibited AChE. There are only three AChE reactivators—HI-6, TO033 and TO047—able to satisfactorily reactivate sarin-inhibited AChE at the concentration 10 -5 M, which is nontoxic for human use. On the other hand, there are 14 AChE reactivators, that are able to reactivate sarin-inhibited AChE at the concentration 10 -3 M. However, this concentration of reactivator is probably toxic for human use. [ABSTRACT FROM AUTHOR]

The efficacy of various oximes to reactivate acetylcholinesterase phosphorylated by tabun (O-ethyl-N,N-dimethyl phosphoramidocyanidate) was tested byin vitroandin vivomethods. The oximes commonly used for the treatment of acute poisonings with highly toxic organophosphates appeared to be almost ineffective (HI-6, pralidoxime, methoxime) or just slightly effective (obidoxime) against tabun. On the other hand, trimedoxime seemed to be a significantly more efficacious reactivator than the others in the case of tabun poisonings.In vitro, the concentration of trimedoxime corresponding to 1.0 mmol/l was able to reach 50% reactivation of tabun-inhibited brain acetylcholinesterase. Higher reactivating potency of trimedoxime in comparison with the other commonly used oximes was demonstrated byin vivomethod, too. In addition, other structural analogues of trimedoxime were found to be efficacious in counteracting tabun-induced acetylcholinesterase inhibition although not as efficacious as trimedoxime itself. Some effective acetylcholinesterase reactivators were characterised by dissociation constant of enzyme-reactivator complex as well as enzyme-inhibitor-reactivator complex and by rate constant of reactivation. [ABSTRACT FROM AUTHOR]

The more criteria a human decision involves, the more inconsistent the decision. This study experimentally examines the effect on the degree of pairwise comparison inconsistency by using the (im)possibility of selecting the criteria for the evaluation and the size of the decision-making problem. A total of 358 participants completed objective and subjective tasks. While the former was associated with one possible correct solution, there was no single correct solution for the latter. The design of the experiment enabled the acquisition of eight groups in which the degree of inconsistency was quantified using three inconsistency indices (the Consistency Index, the Consistency Ratio and the Euclidean distance) and these were analysed by the repeated measures ANOVA. The results show a significant dependence of the degree of inconsistency on the method of determining the criteria for pairwise evaluation. If participants are randomly given the criteria, then with more criteria, the overall inconsistency of the comparison decreases. If the participants can themselves choose the criteria for the comparison, then with more criteria, the overall inconsistency of the comparison increases. This statistical dependence exists only for males. For females, the dependence is the opposite, but it is not statistically significant. [ABSTRACT FROM AUTHOR]

Highly toxic organophosphorus compounds (OPs) were originally developed for warfare or as agricultural pesticides. Today, OPs represent a serious threat to military personnel and civilians. This study investigates the in vivo decontamination of male Wistar rats percutaneously exposed to paraoxon and two potent nerve agents - soman (GD) and VX. Four commercial detergents were tested as decontaminants -Neodekont™, Argos™, Dermogel™, and FloraFree™. Decontamination performed 2 min after exposure resulted in a higher survival rate in comparison with non-decontaminated controls. The decontamination effectiveness was expressed as protective ratio (PR, median lethal dose of agent in decontaminated animals divided by the median lethal dose of agent in untreated animals). The highest decontamination effectiveness was consistently achieved with Argos™ (PR=2.3 to 64.8), followed by Dermogel™ (PR=2.4 to 46.1). Neodekont™ and FloraFree™ provided the lowest decontamination effectiveness, equivalent to distilled water (PR=I.0 to 43.2). [ABSTRACT FROM AUTHOR]

In this work, the two rapid reversed-phase high-performance liquid chromatographic (RP-HPLC) methods were developed for the determination of seven homologues of benzalkonium bromide in hospital disinfectants. The first one uses column Purospher RP- I 8e and mixture of methanol-acetic acid and lithium perchlorate-octanesuiphonic acid aqueous solution as a mobile phase; the second method is performed on Waters Spherisorb Cyano column, and mobile phase consists of acetonitrile-acetate buffer. Both techniques use UV detection at 263 nm. The time of analysis is shorter than 15 mm, and limits of detection are bellow 0.005 mg/mL. [ABSTRACT FROM AUTHOR]

Synthesis of a new asymmetric bisquaternary reactivator of tabun-inhibited acetylcholinesterase-1-(4-hydroxyiminomethylpyridinium)-4-(4-carbamoylpyridinium) butane dibromide is described. Reactivation potency of this oxime is compared to the currently used reactivators—pralidoxime, obidoxime and H-oxime HI-6. [Copyright &y& Elsevier]