Natural Detoxification Capacity to Inactivate Nerve Agents Sarin and VX in the Rat Blood

Background: The method of continual determination of the rat blood cholinesterase activity was developed to study the changes of the blood cholinesterases following different intervetions. Aims: The aim of this study is registration of cholinesterase activity in the rat blood and its changes to demonstrate detoxification capacity of rats to inactivate sarin or VX in vivo. Methods: The groups of female rats were premedicated (ketamine and xylazine) and cannulated to a. femoralis. Continual blood sampling (0.02 ml/min) and monitoring of the circulating blood cholinesterase activity were performed. Normal activity was monitored 1–2 min and then the nerve agent was administered i.m. (2× LD50). Using different time intervals of the leg compression and relaxation following the agent injection, cholinesterase activity was monitored and according to the inhibition obtained, detoxification capacity was assessed. Results: Administration of sarin to the leg, then 1 and 5 min compression and 20 min later relaxation showed that further inhibition in the blood was not observed. On the other hand, VX was able to inhibit blood cholinesterases after this intervention. Conclusions: The results demonstrated that sarin can be naturally detoxified on the contrary to VX. Described method can be used as model for other studies dealing with changes of cholinesterases in the blood following different factors

A Comparison of the Potency of the Oxime HLö-7 and Currently Used Oximes (HI-6, Pralidoxime, Obidoxime) to Reactivate Nerve Agent-Inhibited Rat Brain Acetylcholinesterase by in vitro Methods

1. The efficacy of the oxime HLö-7 and currently used oximes (pralidoxime, obidoxime, HI-6) to reactivate acetylcholinesterase inhibited by various nerve agents (sarin, tabun, cyclosarin, VX) was tested by in vitro methods. 2. Both H oximes (HLö-7, HI-6) were found to be more efficacious reactivators of sarin and VX-inhibited acetylcholinesterase than pralidoxime and obidoxime. On the other hand, their potency to reactivate tabun-inhibited acetylcholinesterase is very low and does not reach the reactivating efficacy of obidoxime. In the case of cyclosarin, the oxime HI-6 was only found to be able to sufficiently reactivate cyclosarin-inhibited acetylcholinesterase in vitro. 3. Thus, the oxime HLö-7 does not seem to be more efficacious reactivator of nerve agent-inhibited acetylcholinesterase than HI-6 according to in vitro evaluation of their reactivation potency and, therefore, it is not more suitable to be introduced for antidotal treatment of nerve agent-exposed people than HI-6

Perkutana toksičnost i dekontaminacija somana, VX-A i paraoksonaza u štakora deterdžentima

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 – NeodekontTM, ArgosTM, DermogelTM, and FloraFreeTM. 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 ArgosTM (PR=2.3 to 64.8), followed by DermogelTM (PR=2.4 to 46.1). NeodekontTM and FloraFreeTM provided the lowest decontamination effectiveness, equivalent to distilled water (PR=1.0 to 43.2).Visokotoksični organofosforni spojevi (krat. OP) prvotno su se proizvodili za ratovanje i uporabi u poljoprivredi kao pesticidi. Danas su nepobitno iznimna prijetnja vojnom osoblju i civilima. Ova studija istražuje in vivo dekontaminaciju muških štakora Wistar perkutano izloženih paraoksonu i dvama snažnim nervnim agensima – somanu (GD) i VX-u. Četiri komercijalna deterdženta ispitana su kao sredstva dekontaminacije - Neodekont, Argos, Dermogel i FloraFree. Dekontaminacija dvije minute nakon izlaganja rezultirala je višom stopom preživljavanja u usporedbi s nedekontaminiranom kontrolnom skupinom. Učinkovitost dekontaminacije izražena je kao zaštitni omjer (PR, medijan smrtonosne doze agenta u dekontaminiranih životinja podijeljen s medijanom smrtonosne doze agenta u nedekontaminiranih životinja). Najveća konzistentna učinkovitost postignuta je Argosom (PR=2.3 do 64.8) i Dermogelom (PR=2.4 do 46.1). Deterdženti Neodekont i FloraFree bili su najmanje učinkoviti i imali jednak učinak kao destilirana voda (PR=1.0 do 43.2)

Effect of Traffic Noise and Relaxations Sounds on Pedestrian Walking Speed

Exposure to noise in everyday urban life is considered to be an environmental stressor. A specific outcome of reactions to environmental stress is a fast pace of life that also includes a faster pedestrian walking speed. The present study examined the effect of listening to annoying acoustical stimuli (traffic noise) compared with relaxation sounds (forest birdsong) on walking speed in a real outdoor urban environment. The participants (N = 83) walked along an urban route of 1.8 km. They listened to either traffic noise or forest birdsong, or they walked without listening to any acoustical stimuli in the control condition. The results showed that participants listening to traffic noise walked significantly faster on the route than both the participants listening to forest birdsong sounds and the participants in the control condition. Participants who listened to forest birdsong walked slightly slower than those under control conditions; however, this difference was not significant. Analysis of the walk experience showed that participants who listened to forest birdsong during the walk liked the route more than those who listened to traffic sounds. The study demonstrated that exposure to traffic noise led to an immediate increase in walking speed. It was also shown that exposure to noise may influence participants’ perception of an environment. The same environment may be more liked in the absence of noise or in the presence of relaxation sounds. The study also documented the positive effect of listening to various kinds of relaxation sounds while walking in an outdoor environment with traffic noise

Effect of birdsongs and traffic noise on pedestrian walking speed during different seasons

Many studies have explored the effects of auditory and visual stimuli on the perception of an environment. However, there is a lack of investigations examining direct behavioral responses to noise in specific environments. In this study, a behavioral variable, walking speed, was analyzed, as a response to the sounds and visual features of a specific environment. The study examined the effects of birdsongs compared to traffic noise on walking speed in a real outdoor urban environment. It was supposed that the interaction of audition and vision in the perception of an environment may also be shaped by the perceived congruence of the visual and auditory features of the environment. The participants (N = 87 and N = 65), young university students, walked along a 1.8-km urban route. They listened to a soundtrack of crowded city noise or birdsongs, or they walked in the real outdoor environment without listening to any acoustic stimuli. To investigate the effect of the congruence between acoustic and visual stimuli, the experiment was conducted in two different seasons (fall and spring). The results did not show significant differences between the crowded city noise condition and the real outdoor condition. Listening to the soundtrack with birdsongs decreased walking speed, but this effect was significant only in the experiment conducted in spring. These findings can be explained in terms of the congruence between the sounds and the visual environment. The findings raise questions regarding the restorative function of urban greenery during different seasons

The Influence of Criteria Selection Method on Consistency of Pairwise Comparison

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