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The bachelor's thesis deals with the issue of the misuse of chemical warfare agents in a terrorist attack. In the theoretical part, the terms terrorism, chemical terrorism, dangerous chemical substances and mixtures and chemical warfare agents were defined on the basis of legal regulations and professional literature. Furthermore, chemical warfare agents are described in detail, the possibilities of their spread, effects of use and, based on a theoretical study of sources, a list of serious terrorist acts in which chemical agents have been used and the current security situation in the fight against chemical terrorism in the Czech Republic. In the practical part, selected BCHL were evaluated on the basis of significant kriteria and simulated a terrorist attack in the Prague metro. The aim of the work was to evaluate the possibilities of misuse of selected BCHL in a terrorist attack and to answer the research question whether the use of chemical terrorism in the Czech Republic is currently a threat. Based on the obtained results, it can be stated that chemical terrorism is currently a threat in the Czech Republic. The reason is the relatively easy availability of these substances, the low financial costs of carrying out an attack and the minimum requirements for the expertise of attackers. The work offers a relatively comprehensive view of the issue.

This bachelor thesis deals with the Integrated Rescue System, its components and preparedness of these components for intervention in case of the attack of chemical weapons. The aim of the thesis was to find out whether the selected basic components of the Integrated Rescue System are able to respond to the danger caused by the chemical weapons attack. The thesis is divided into two parts. The first part is theoretical, general characteristics of chemical weapons are described here. Furthermore, the history of the development of chemical weapons is briefly mentioned, important milestones in this area are added, such as the first use of a chemical weapon. The next point is the description of the individual chemical warfare agents, the description includes the basic characteristics, effects on the body, and possible protection against them. Part of my thesis is devoted to IRS itself, means of individual protection and decontamination. The last chapter of the theoretical part deals with the Convention on the Prohibition of Development, Production, Stockpiling and Use of Chemical Weapons and Their Destruction. The second part, i.e. the practical part, defines the methods and objectives of the research itself and the results that are graphically processed for the sake of clarity. Subsequently, the results are described in the discussion. The goal of the thesis was to answer the research question. Are the basic components of the Integrated Rescue System ready to possible attack by chemical weapons? To ensure this information, a questionnaire survey was used to fill the basic components. A total of 54 people participated in this survey. Research has revealed that the knowledge of the chemical weapons components of the IRS is low, from which it can be concluded that the components are not sufficiently prepared to attack chemical weapons. The practical contribution of this thesis should be mainly to increase the number of exercises related to this issue and increase the theoretical preparation of the monitored components of the Integrated Rescue System.

The goal of this theses is to analyse the preparedness of Prague Emergency Medical Services (hereinafter Prague EMS) for chemical attack in subway (metro). The theoretical part states general information about chemical terrorism and the Integrated Rescue System's solution. The research part focuses on procedures following from Integrated Rescue System Common Type Activity during joint action - Reaction on chemical attack in subway (hereinafter STČ 13/IZS). This document was subjected to content analysis to meet the goals. The work then focuses on the evaluation of Prague EMS training Metro 2014 whose goal was to practice the procedures and joint deployment of Integrated Rescues System members and other subject according to STČ 13/IZS. For the evaluation complexity, the results were supplemented by SWOT analysis which pointed at another usable knowledge. All conclusions are clearly organized in charts and they are efficiently worked with to set new measures and recommendations which would increase the preparedness of Prague EMS for chemical attack in metro. The goal of this work to assess the level of preparedness and to submit final protocol to organisation's crisis management was fulfilled. The main benefit of this work is a recommendation for the reinforcement of crisis preparedness at Prague EMS. Furthermore the work brings new expert findings to solved problematics.

In the article the author in his memoirs ponders the military-political aspects of the presence of toxic substances in the Gulf War in 1990-1991, measured by chemists from the 1st Czechoslovak independent chemical protection battalion. The thesis provides a comprehensive look at the history of its origin, its own deployment of in the war, and access to public administrations to its members after returning from the war.

This thesis is dedicated to the topic of the nerve agents with special emphasis on antidotal treatment utilizing application of the auto-injectors. Two methods were used ? literature research and quantitative research. Since this topic covers plenty of information as regards chemical warfare agents and in particular nerve agents these issues were addressed in the theoretical part of the thesis. In the chapter on current status based on literature resources a summary of evolution of the auto-injector is presented; from firsts notes until the situation today. Practical part of the thesis is concentrated on University of Southern Bohemia in ČeskéBudějovice, Faculty of Health and Social Studies students' knowledge in the area of nerve agents. The results of the research were acquired by the method of quantitative research ? questionnaires with 18 questions. With respect to each of the questions a selection of the 2 to 7 answers was offered to the students, whereas in every case only 1 answer was correct. The results were analyzed both with reference to each of the questions and with reference to each of the students. By this method it has been discovered that the respondents have a good knowledge in the area of nerve agents. Furthermore, the practical part of the thesis included an experiment concerning speed with which the respondents were able to apply antidotum with a training auto-injector by themselves with no prior instructions in comparison to how quickly they were able to do the same after being instructed. By this method were tested the quality of the instructions provided to the auto-injectors and its ergonomic qualities (intuitiveness of its application). Recorded times were statistically analyzed and the results, although materially different, were assessed as satisfactory.

Chemical weapons are justly considered by the human society as the oldest type of weapons of mass destruction. Unfortunately the same human society has continued to apply and further develop the ancient principles of use of combat chemical substances. The current world, despite all the humanistic efforts to terminate the history of this type of weapons, continues to be physically threatened by their abuse. I must say that studies of the history of chemical weapons are very demanding and comprehensive. The whole process of historic development of these combat means is interconnected by multiple relations and circumstances and unfortunately has been the source of a lot of inconceivable human suffering. That is why I decided to take the courage and thread the path leading to a look back at the past, for I believe that such a retrospective not only reveals stories that are already buried in the distant past and are not needed any more, but also leads to understanding the present, learning a lesson from past mistakes and acquiring a humble approach to life. On the basis of studies of the many available resources I tried to submit in my diploma thesis a complex summary of current as well as historic knowledge of combat chemical substances, their research and testing on humans. While the issue of chemical weapons and wars as such is paid a lot of attention, the issue of chemical weapon testing on people has still been a marginal theme. The abovementioned facts inspired this thesis and I believe that my diploma theses might be beneficial for its readers. My greatest desire and aim was to present to the readers the historic path of application and the related research and testing of chemical weapons. I hope I have processed the theme to be better understandable to the reader, both professional and lay. I tried to proceed systematically and make my thesis interesting to enrich not only me but also its readers.

The effect of atropine and diazepam on the mammalian neuromuscular junction. Nicotinolytic effect of atropine on the neuromuscular junction is discussed as a main mechanism of the beneficial effect of this drug during war and agriculture poisoning by anticholinesterases. Atropine is beneficial as it reduces the amplitude of intracellularly recorded endplate potentials and, first of all, causes a marked shortening of their time course (Beránek, Vyskocil 1968, Magazanik, Vyskocil 1969). Diazepam effectively blocks trains of action potentials in individual rat diaphragm muscle fibers, apparently by elevating the chloride permeability. It is suggested that similar increase in Cl- permeability may occur in brain excitable structures and can counteract the anticholinesterase-induced prolongation of ACh-depolarization that evokes repetitive firing.

Antioxidants perform an important role in the maintenance of the integrity of the living organisms. Recently, great attention has been given to antioxidants by a reason of their medical use. It is due to the association of many human diseases with oxidative stress. The present study briefly surveys the types of antioxidants, reactive oxygen and nitrogen species and describes the basic mechanisms of their activity. The application of antioxidants in the therapy of the injury caused by sulfur mustard, a vesicant type chemical warfare agent introduced in World War I, is also given.

Chemical weapons count among the weapons of mass destruction. In addition to chemical weapons, also nuclear and biological weapons belong here. Historically, chemical weapons rank among the oldest ones. Their initial steps were made in the distant past, even if they were not called so then. However, the initial utilization of chemical agents against human force is more connected with fire. It was used for protection against attacks of animals as well as people. Later on it was used to protect or capture towns and fortifications. The most extensive use of chemical weapons in war occurred during World War I. A large number of chemical substances was tested, the most important being phosgene. In 1917, German army used vesicant yperite near the town of Ypres. The development of chemical warfare agents continued also after the year 1918. During World War II, chemical weapons were practically not used. If it happened, then on the secondary fronts only. The main reason was the fear of possible retaliation. From 1939 to 1945, huge amounts of chemical warfare agents were made. Towards the end of the war this stockpile amounted to approximately 400 000 tonnes. After World War II, a new stage of chemical armament has begun. The greatest attention was concentrated on nerve agents, sarin, soman and agent VX. Chemical warfare agents have been further used also after the year 1945. In the not so distant past, Iraq used nerve-paralyzing agents and yperite during the Iran-Iraq War (1980 {--} 1988). Last but not least, the use of chemical warfare agents for terrorist purposes is to be mentioned. In January 1993, the global fight against chemical weapons culminated in signing of the Convention on the Prohibition of the Development, Production, Stockpiling and Use of Chemical Weapons and on Their Destruction. Under this Convention, chemical weapons were to be liquidated until the year 2007. States Parties to the Chemical Weapons Convention which did not comply with this deadline have asked for prolongation of the final deadlines for chemical weapons liquidation until 29 April 2012. The question remains if even this prolongation will fulfil the goal of the Convention {--} to ensure a world without chemical weapons. Until the time when the stockpiles of chemical weapons are completely liquidated their possible misuse cannot be excluded. The states which have not joined the Convention as yet and own limited stockpiles of chemical weapons can use them.

The protection of population in case of terrorist attack which includes the release of dangerous substances My Bachelor Thesis on the topic Protection of population in case of terrorist attack which includes the release of dangerous substances is divided into two parts. In the theoretical part I deal with development of population protection in the CR, as the basic element of population protection against dangerous substances, its differentiation and its basic tasks, then I describe types and examples of emergency events (terrorist attack, release of dangerous substances in the atmosphere in relation to the population behaviour principles). The practical part is aimed at investigation of awareness of inhabitants of protection of population in case of terrorist attack which includes the release of dangerous substances. The aim of my work is to confirm or to disprove the following hypotheses. Citizens have sufficient opportunities to get familiarized with the issue of protection of population in case of terrorist attack which includes the release of dangerous substances. Citizens know the principles of correct behaviour in emergency events. The next aim is to compile material providing summarized information on the principles of population behaviour in emergency situation involving harmless substance release, to specification of the possible most frequent and most dangerous substances, their main effects and basic features applied in accidents, to explain some basic ways of warning labelling of dangerous substances. The elaborated material will be offered to teachers of these issues for use in education according to the Ministry of Education Instruction No. 12050/03-22 of 4 March 2003. The questionnaire form was used for elaboration of the practical part. The questionnaire consisted of twenty-five questions. The first four ones are aimed at the characteristics of the examined sample of respondents (sex, age, education, place of residence size). The following questions were already aimed at investigation of awareness of South Bohemian Region inhabitants of protection of population in case of terrorist attack which includes the release of dangerous substances. The research was performed in January and February 2007. 120 questionnaires were distributed. The research target group consisted of South Bohemian Region inhabitants. 120 randomly selected respondents participated in the research. The results of the practical part prompt that citizens have sufficient opportunities to get familiarized with the issues of population protection. There are enough sources of information nowadays, just to use them. We may say to the second hypothesis that according to my research citizens have basic information on the principles of correct proceeding in case of emergency events. However their awareness is not at the sufficient level. I believe that this thesis will contribute to enlargement of knowledge of population protection, which might substantially influence behaviour of people in case of dangerous substance release or a terrorist attack.

The nerve agent tabun inhibits acetylcholinesterase (AChE; EC 3.1.1.7) by the formation of a covalent bond with the enzyme. Afterwards, AChE is not able to fulfil its role in the organism and subsequently cholinergic crisis occurs. AChE reactivators (pralidoxime, obidoxime and HI-6) as causal antidotes are used for the cleavage of the bond between the enzyme and nerve agent. Unfortunately, their potency for reactivation of tabun-inhibited AChE is poor. The aim of the study was to choose the most potent reactivator of tabun-inhibited AChE. We have tested eight AChE reactivators--pralidoxime, obidoxime, trimedoxime, HI-6, methoxime, Hlö-7 and our newly synthesized oximes K027 and K048. All reactivators were tested using our standard in vitro reactivation test (pH 8, 25 degrees C, time of inhibition by the nerve agent 30 minutes, time of reactivation by AChE reactivator 10 minutes). According to our results, only trimedoxime was able to achieve 50% reactivation potency. However, this relatively high potency was achieved at high oxime concentration (10(-2) M). At a lower concentration of 10(-4) M (the probably attainable concentration in vivo), four AChE reactivators (trimedoxime, obidoxime, K027, and K048) were able to reactivate AChE inhibited by tabun reaching from 10 to 18%.

The therapeutic efficacy of selected reactivators of acetylcholinesterase (obidoxime, oxime HI-6, trimedoxime) against acute tabun poisoning in dependence on their dose was examined in experiments on male mice. A comparison of the values of the medium lethal dose (LD50) of tabun in the intoxication influenced by an antidote therapy consisting of atropin and some of the oximes tested revealed that in all three oximes under study their dose markedly influenced their effect. The highest efficacy was always achieved when oximes were administered in the maximal therapeutic dose (20% of LD50). It follows from the comparison of the efficacy of equieffective doses of the oximes tested that in all doses the acute lethal effects of tabun are most effectively eliminated by trimedoxime, and on the other hand, obidoxime seems to be least effective, though in the smallest dose tested (2% of LD50) the differences between the therapeutic efficacy of the individual oximes are not statistically significant. Oxime HI-6 is significantly more effective than obidoxime (in a dose corresponding to 20% of LD50), but it is less effective than trimedoxime (in a dose corresponding to 5% LD50). The achieved results have shown that oxime HI-6, so effective against soman, another nerve agent, is not the most advantageous reactivator of acetylcholinesterase for the therapy of acute tabun poisonings, though its efficacy is partly eliminated by its possible higher dosing in human medicine due to its lower toxicity for mammals. The most suitable reactivator of acetylcholinesterase for the elimination of acute lethal toxic effects of tabun seems to be trimedoxime. Obidoxime, which is the most widely used reactivator of acetylcholinesterase in the therapy of poisonings by nerve agents at present, is, like in the case of soman poisonings, a relatively least suitable oxime ensuring the survival in lethal tabun poisonings.

Since thirties of the previous the highly toxic organophosphorus compound called nerve agents have been considered the most dangerous chemical warfare agents that could be misused in local and world wars or during terrorist attacks. Beside the historical introduction, the article summarizes contemporary knowledge on the mechanism of toxicity of these agents, on the possibilities of diagnosis, prophylaxis and treatment. The possibility of using similar methods of diagnosis, prophylaxis and treatment for acute poisoning with organophosphorus insecticides is also mentioned.

The currently used antidotal treatment of intoxication with nerve agents, consisting of an anticholinergic drug and an acetylcholinesterase reactivator, is often completed with the anticonvulsive drug diazepam to prevent poisoned organisms from centrally mediated seizures and subsequent tonic-clonic convulsions. The aim of this study was to find out whether the complementation of the antidotal treatment with diazepam can influence antidotal treatment-induced elimination of acute lethal effects of the chosen nerve agent--soman.In experiments on mice, the values of medium lethal dose of soman in the case of 24 h surviving of soman-exposed mice, treated with the basic antidotes involving various types of anticholinergic drugs and acetylcholinesterase reactivators, were evaluated and compared to the values of medium lethal dose of soman in mice treated with antidotes completed with diazepam. Our findings confirm that diazepam is able to enhance the efficacy of basic antidotal treatment to eliminate acute lethal effects of soman if atropin is used as anticholinergic drug. On the other hand, no ability of diazepam to enhance soman-induced lethal effects was demonstrated if an anticholinergic drug with central effects such as benactyzine, biperiden or scopolamin was used. The ability of diazepam to influence the efficacy of antidotes to eliminate soman-induced acute lethal effects was only observed in the case of using the oxime HI-6 as acetycholinesterase reactivator.The most perspective antidotal mixture against soman, consisting of the oxime HI-6 and atropine, should be complemented by diazepam no only because of the prevention of poisoned organisms from centrally mediated seizures and subsequent tonic-clonic convulsions but also because of the increase in the ability of antidotal treatment to eliminate soman-induced acute lethal effects.

Experiments on male rats examined the effect of a basic antidotal therapy consisting of various types of anticholinergic substances and reactivators of acetylcholinesterase on the lethal effects of the highly toxic organophosphorous compound soman by means of determination of the medium lethal dose of soman in 24-hour survival of experimental animals. The efficacy of the basic antidotal therapy of acute intoxications by soman evaluated in this way was compared with the effect of an antidotal therapy enriched with diazepam, a drug with anticonvulsive action. The obtained results show that addition of diazepam to the basic antidotal therapy increases the ability of the antidotal therapy to eliminate acute lethal effects of soman if it includes atropine as an anticholinergic agent regardless of the employed type of acetylcholinesterase reactivator. In the case of employment of anticholinergic agents with prevailing central effects, such as benactyzine, biperiden, or scopolamine, the addition of diazepam will not significantly influence the therapeutic efficacy of the antidotal therapy regardless of the selected aetylcholinesterase reactivator. At the same time, the addition of diazepam to the antidotal therapy does not change the difference in the efficacy of the antidotal therapy in dependence on the selected anticholinergic agent or acetylcholinesterase reactivator. At present the most common combination of antidotes against soman, consisting of obidoxime and atropine, as well as a prospective combination containing oxime HI-6 and atropine should be supplemented with diazepam not only to prevent centrally induced seizures and tonic-clonic convulsions but also to increase the ability of such antidotal therapy to eliminate acute lethal toxicity of soman.

Acute poisoning with the highly toxic organophosphorus agent, soman, is not treated satisfactorily even by the most modern antidotes.In experiments on rats, the reactivating effect of a new asymmetric bispyridinium oxime BI-6 was compared with widely used oximes HI-6 and obidoxime by investigating the changes of soman-inhibited acetylcholinesterase activity in the diaphragm and various parts of the brain in rats up to three hours following soman challenge. Our findings confirm that the new oxime BI-6 is a more effective reactivator of soman-inhibited acetylcholinesterase than obidoxime but not as effective as the oxime HI-6 especially in the peripheral compartment.The new oxime BI-6 is not as effective as HI-6 which seems to have definite advantages over other oximes in the treatment of soman poisoning.

The therapeutic efficacy of the new asymmetric bispyridinium oxime BI-6 against acute toxicity of the highly toxic organophosphate soman and the organophosphorus insecticide fosdrin by means of affecting the LD50 values of these noxiores substances was compared with the effect of the hitherto most perspective oxime HI-6 and the classic obidoxime always in combination with the identical dose of atropine. At the equimolar level the effect of oxime BI-6 against fosdrin completely equals the effects of both oximes HI-6 and obidoxime. The effect of oxime BI-6 against soman is even more marked than the effect of HI-6 but this difference is not statistically significant. On the other hand, at the equi-effective level, the effect of oxime BI-6 against soman is statistically significantly lower than the effect of HI-6, and against fosdrin it is even lower than the effect of both remaining oximes. The effects of the new oxime BI-6 equal, or slightly exceed the therapeutic effect of HI-6 but at the equimolar level only. At the equi-effective level which respects the toxicity of the oxime and is therefore more important for practical use, it is a therapeutically weaker reactivator of acetylcholinesterase than HI-6.

The pharmacological prophylaxis protecting the organism against organophosphorus compounds could increase the effect of antidotal treatment of poisoning with organophosphates.The influence of the pharmacological prophylaxis with Panpal (pyridostigmine in combination with benaetyzine and trihexyphenidyle) on acetylcholinesterase activity in diaphragm and various parts of brain at 1 and 3 h following non-treated and treated (the oxime HI-6 in combination with atropine) soman poisoning was tested on male rats. While Panpal did not significantly influence the acetylcholinesterase activity in brain following non-treated as well as treated soman poisoning. Panpal increased so many-induced acetylcholinesterase inhibition following non-treated poisoning and decreased the reactivating effect of the oxime HI-6 following treated soman poisoning in diaphragm.Our data confirm the importance of the combination of reversible acetylcholinesterase inhibitor pyridostigmine with anticholinergic drugs in the pharmacological prophylaxis of soman poisoning because of the elimination of consequences of pyridostigmine-induced increasing in acetylcholinesterase inhibition in the peripheral compartment.

The efficacy of cholinesterase reactivators tetroxime, HI-6 and obidoxime in combination with atropine against highly toxic organophosphate soman as well as organophosphorus insecticide fosdrin was evaluated in male mice using median lethal dose (LD50) for 48 hours. Oxime HI-6 appears to be considerably more effective than tetroxime as well as obidoxime for the treatment of acute poisonings by soman or fosdrin, although the difference in effect is not significant in the case of poisoning by fosdrin. These findings suggest that HI-6 has definite advantage over obidoxime as well as tetroxime in the treatment of poisoning with not only highly toxic organophosphates but also organophoshorus insecticides.