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Human butyrylcholinesterase (hBChE) is well-known stoichiometric scavenger in case of organophosphorus (OP) intoxication. However, its major limitation lies in binding of only one OP moiety per hBChE molecule and thus necessity of its very high dosage prior or post intoxication. This issue might be resolved by use of hBChE reactivators that could cleave irreversibly bound OP moiety from the enzyme active site and restore its scavenging function. This concept has been called pseudo-catalytic scavenger. Within our contribution, we would like to present bisquaternary heteroaromatic compounds that are butyrylcholinesterase reactivators and might act as potential pseudo-catalytic bioscavengers. Recently, we have prepared and evaluated over 20 novel compounds that displayed better hBChE reactivation activity than clinically used reactivators.

Chronic illness from exposure to organophosphorus toxicants is hypothesized to involve modification of unknown proteins.  Tyrosine readily reacts with organophosphorus toxicants in proteins that have no active site serine.  We developed a monoclonal antibody, depY, that specifically recognizes diethoxyphospho-tyrosine in proteins and peptides, independent of the surrounding amino acid sequence ¹. Our goal was to identify diethoxyphosphorylated proteins in human HEK293 cell lysate treated with chlorpyrifos oxon.  Cell lysates treated with chlorpyrifos oxon were examined by ELISA and capillary electrophoresis Western blot.  Tryptic peptides were analyzed by liquid chromatography-tandem mass spectrometry.  The depY antibody recognized diethoxyphospho-tyrosine containing proteins by ELISA and Western blotting.  Mass spectrometry identified 40 diethoxyphospho-tyrosine peptides from 24 proteins in immunopurified samples, but found only 9 diethoxyphospho-tyrosine peptides from 6 proteins when the same sample was not immunopurified on depY. The most abundant proteins in the cell lysate, Histone H4, Heat shock 70 kDa protein 1A/1B, Heat shock protein HSP 90 beta, and Alpha-enolase, were represented by several diethoxyphospho-tyrosine peptides.  It was concluded that use of immobilized depY improved the number of diethoxyphospho-tyrosine peptides identified in a complex mixture.  The mass spectrometry results confirmed the specificity of depY for diethoxyphospho-tyrosine peptides independent of the context of the modified tyrosine, which means depY could be used to analyze modified proteins in any species.

Ten phenyltetrahydroisoquinoline-based compounds synthesized using alkyne+azide [3+2] building block cycloaddition were tested as potential reactivators of human acetylcholinesterase (hAChE) inhibited by different organophosphates. Computational docking indicated molecule phenyltetrahydroisoquinoline moiety association with the hAChE peripheral anionic binding site (Trp286, Tyr337 and Tyr341). Therefore, stabilization near the gorge opening seemed to control the general orientation of the pyridinium ring with its attached aldoxime group inserted into the internal gorge of the hAChE active center. All of the oximes were tested in vitro as potential reactivators of sarin-, cyclosarin-, tabun- and VX-conjugated hAChE and potent reactivators were identified, especially with the cyclosarin-hAChE conjugate. Nevertheless, in order to acquire results applicable to reactivation in vivo, compounds should be tested at concentrations higher than 10µM, which proved limiting due to the concomitant reversible inhibition of unconjugated hAChE. High oxime affinity was observed for hAChE, but not for human butyrylcholinesterase, where an aromatic peripheral site is absent. Therefore, we tested the oximes as reversible inhibitors of hAChE. All of the compounds potently inhibited hAChE with dissociation inhibition constants in nM range. To further explore potential for safe antidotal activity, we tested oxime cytotoxicity on the human neuroblastoma SH-SY5Y cell line. No cytotoxicity was observed at studied concentrations. In conclusion our study has shown that likely binding poses of an oxime in the hAChE active center do not always ensure enhanced enzyme activity for in vivo reactivation. Very high affinity of a candidate oxime for unconjugated hAChE may prove counterproductive for reactivation in tissue.

Neurodegenerative diseases are multifactorial. Therefore, their treatment requires drugs that can act simultaneously on multiple pathogenic targets. We synthesized several series of hybrid structures combining certain pharmacophores essential for neurodegenerative disease treatment: γ-carbolines, carbazoles, phenothiazines, and aminoadamantanes [1-3]. Inhibitory activity of these conjugates against acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and carboxylesterase (CaE) was studied along with their ability to competitively displace propidium iodide from the peripheral anionic site of electric eel AChE to assess their potential effect on AChE-induced aggregation of β-amyloid. Antioxidant properties were examined computationally with density functional theory and measured experimentally using 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid (ABTS) and oxygen radical absorbance capacity (ORAC-FL) assays. Binding modes of conjugates to AChE and BChE were studied using quantum mechanical-assisted molecular docking. Results revealed structures that were selective inhibitors of BChE [1,2] or that combined high potency and selectivity toward BChE with high radical-scavenging activity, e.g., conjugates of γ-carbolines and tetrahydrocarbazoles [3]. Conjugates of γ-carbolines and cycloalcaneindoles with the phenothiazine derivative Methylene Blue demonstrated high potency against AChE and BChE combined with effective displacement of propidium from the peripheral anionic site of AChE. Additionally, the conjugates were extremely active in both antioxidant tests. All conjugates were poor CaE inhibitors and therefore expected to lack drug-drug interactions by this pathway. Good agreement was found between experimental and computational results. Lead compounds were identified for future optimization and development of new multi-target drugs against neurodegenerative diseases that combined cognition enhancement with neuroprotective potential.

Acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) hydrolyze the neurotransmitter acetylcholine and function thereby as regulators of cholinergic neurotransmission. Recently, interest has greatly increased in BChE. Firstly, BChE is a good broad spectrum bioscavenger of nerve agent and its efficiency could be significantly increased by the mean of specific reactivators. Secondly, BChE activity in the brain increases with the progression of Alzheimer’s disease, thus classifying BChE as a promising drug target in the advanced phase of the disease. AChE and BChE display specificities for substrates and ligands that only partially overlap. This disparity is largely due to differences in the number of aromatic residues lining the active site gorge, which leads to large differences in the shape of the gorge and potentially to distinct interactions with an individual ligand. Considerable structural information is available for the binding of a wide diversity of ligands to AChE. In contrast, structural data on the binding of reversible ligands to BChE was lacking. In the recent years, we solved the X-ray structures of multiple BChE-ligand complexes. Here we will present BChE structures with various ligands, some recently synthesized, to highlight the structural elements leading to their BChE affinity and specificity. These structural data will help to design specific reversible ligands that behave as inhibitors or reactivators.

Human acetylcholinesterase (hAChE) is responsible for degrading neurotransmitter acetylcholine at synapses of the nervous system. Organophosphate (OP) nerve agents and pesticides inactivate hAChE through chemical modifications of the catalytic serine. The current generation of oxime antidotes is not highly efficient. Insights into the molecular structures of AChEs from various species reveal possible limitations in enhancing reactivation rates, but provide only limited information, because the structures have been obtained at cryo-temperatures. Moreover, X-ray crystallography usually cannot resolve positions of hydrogen atoms involved in proton transfer processes during reactivation. Thus, we use room-temperature X-ray and neutron crystallography to obtain structures at physiological conditions and to visualize hydrogen atoms. Several X-ray structures of native and VX and POX-conjugated hAChE in complex with oxime reactivators, RS2-170B and RS-194B have been obtained. hAChE crystallized in a unit cell (a=124.3, c=129.1 Å; P3₁) amenable to neutron crystallography. For the first time we show how RS2-170B binds in the non-modified and OP-conjugated active site gorge at room temperature. RS-194B is observed with its oxime group pointing away from the catalytic Ser203 and the reactivator is pushed out to bind at the peripheral site in the VX-modified structure. Dynamics of hAChE was probed by neutron vibrational spectroscopy to look at harmonic vibrations. POX binding induces significant changes in the acyl pocket loop conformation expelling the weakly binding RS-194B from the active site gorge completely, and the loop becomes more dynamic. We hypothesize that increased dynamics of the acyl pocket loop contributes to the POX-conjugated hAChE resistance to reactivation.

Several flavonoids have been identified to induce the expression of AChE in PC12 cells, e.g. daidzin, irisflorentin, cardamonin and genistein. Among them, genistein is the most robust inducer for AChE activity. Genistein, 4',5,7-trihydroxyisoflavone, is a major isoflavone in soybean, which is known as phytoestrogen having known benefit to brain functions. Being a common phytoestrogen, the possible role of genistein in the brain protection needs to be further explored. In PC12 cells, application of genistein significantly induced the expression of neurofilaments, markers for neuronal differentiation. In parallel, the expression of tetrameric form of proline-rich membrane anchor (PRiMA)-linked acetyl-cholinesterase (G4 AChE), a key enzyme to hydrolyze acetylcholine in cholinergic synapses, was induced in a dose-dependent manner: this induction included the associated protein PRiMA. Genistein-induced AChE expression was fully blocked by the pre-treatment of H89 (an inhibitor of protein kinase A) and G15 (a selective G protein-coupled receptor 30 (GPR30) antagonist), which suggested a direct involvement of a membrane-bound estrogen receptor-GPR30-in the cultures. In parallel, the estrogen-induced activation of GPR30 induced AChE expression in a dose-dependent manner. The genistein/estrogen-induced AChE expression was triggered by a cyclic AMP responding element (CRE) located on the ACHE gene promoter. The binding of this CRE site by cAMP response element-binding protein (CREB) induced ACHE gene transcription. We have shown for the first time the activation of GPR30 could be one way for estrogen or flavonoids, possessing estrogenic properties, to enhance cholinergic functions in the brain, which could be a good candidate for possible treatment of neurodegenerative diseases.

The ongoing coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has become a global health crisis. Flavon baicalein, a major bioactive molecule of Scutellaria baicalensis, inhibits the replication of SARS-CoV-2 which causes severe acute respiratory syndrome in humans. Animal experiments show that baicalein has the character of a broad-spectrum coronavirus drug. It is non-toxic and can inhibit SARS-CoV-2-induced damage. Baicalein may therefore be a promising therapeutic drug for the treatment of COVID-19.

One of the major economical expense for health providers in wound care management are patients with diabetic foot ulcer or a chronic lower limb ischemia. Main treatment goal in theese patients is usually reduction in a number of amputations, especially high-ones, deeply affecting quality of life of patients. Hyperbaric medicine is already estabilished as an adjuvant method in some of these indications. In some cases it is already part of the national recomendations for diabetic foot ulcer treatment. The aim of this work is to present recent clinical systematic reviews and currently valid recommendations for the treatment of difficult-to-heal ulcers according to the 10^th European Consensus Conference ECHM (European Commission for Hyperbaric Medicine) from 2016. Part of the work is an overview of pharmacoeconomic studies, summary of treatment costs for diabetes, its complications, in patients after amputations as well as costs of HBOT. Finally, the principle and significance of the method of transcutaneous oximetry and the so-called oxygen challenge in relation to HBOT in patients with critical ischemia and diabetic foot syndrome are explained.

BACKGROUND: Damaged arteries bleeding can cause a life-threatening condition and it is one the main causes of death which can be prevented both on the battlefield and in the civilian environment. In case when severe external bleeding in a limb cannot be controlled by direct pressure a tourniquet should be used. The purpose of this study was to test four different types of tourniquets and to determine which type of tourniquet is effective to be used in the Army of the Czech Republic. METHODS: Four different types of tourniquets were tested: SOFTT, C-A-T Generation 6, C-A-T Generation 7 and the CZ Tactical tourniquet. 59 students of military medicine (35 males and 24 females) from the Faculty of Military Health Sciences volunteered for the study. Each student applied all four types of tourniquets by self-application on the non-dominant upper arm. 20 students applied all four types of tourniquets on the arm as a buddy aid. Tourniquets order was determined by randomization. Time to placement, effectiveness and a subjective assessment of the application were recorded. RESULTS: The C-A-T 7 tourniquet was the fastest applicable one, with 52, 5% of students being able to apply it up to 30 seconds. In the range of 31-60 seconds, 66, 1% of the C-A-T 6 and 54, 2% the CZ Tactical tourniquets were applied. On the contrary, the SOFTT tourniquet, as the only one, 5, 1% exceeded the application time of 2 minutes. The C-A-T 7, the C-A-T 6 and the CZ Tactical tourniquets were more effective (95%, 95% and 86%, respectively) compared with the SOFTT (56%). The correct application was found in men in 89% of the cases, while in women in 74% of the cases. A higher rate of failure was recorded for women in all types of the tourniquets. Average subjective students´ score was in the tourniquet SOFTT 3, 46 (assessment between neutral and difficult), the other tourniquets were assessed between easy and very easy (C-A-T 6 1.63, CZ Tactical tourniquet 1.46 and C-A-T 7 1.34). CONCLUSIONS: The C-A-T 7 tourniquet was best evaluated, followed by the CZ Tactical tourniquet, the C-A-T 6 and the SOFTT.  A significant difference between C-A-T 7, CZ Tactical tourniquet and C-A-T 6 on one side and SOFTT one the other side and a significant difference between male and female correct tourniquet application was found out. TRIAL REGISTRATION: The trial was approved by the IRB of the Faculty of Military Health Sciences of the University of Defence, Czech Republic (No. MO 4330/2017-2994 HK).

Coronavirus 2 (SARS- CoV-2) leads to Coronavirus disease 2019, is recognized as a lethal epidemic in 2020. SARS-CoV-2 is an enveloped, non-segmented, positive sense RNA virus that belongs to the beta-corona family of viruses. The genome of this virus is about 30 kb representing 16 non-structural proteins (Nsp1-16), four structural proteins (N, M, E, S) and nine accessory proteins are encoded by its genome, which are involved in survival and pathogenesis the viruses. In order to produce medicines and vaccines for SARS-CoV-2, it is essential to fully understand the genomic structure of the virus and function of its proteins. This review collects and investigates the functional properties of SARS-CoV-2 proteins that have been reported to date.

Cynomorium coccineum and Cynomorium songaricum are unusual parasitic plants in the family Cynomoriaceae characterized by their unusual appearance and way of life. Due to their special habit and extremely rare occurrence, in the past, various magical properties have been attributed to these plants. The plant Cynomorium coccineum, which is found in the Mediterranean, has been used in Europe since the Middle Ages in folk medicine under the name fungus maletensis (maltese fungus). It was used for the same purpose in Arabic cultures under the name tarthuth. The Asian species (Cynomorium songaricum), sometimes considered a subspecies of C. coccineum, is still used in traditional Chinese medicine under the name Suo Yang. Recent studies show that the plant has a number of beneficial effects on the body and there is a real possibility that the substances present in Suo Yang or substances derived therefrom will be used in the future for therapeutic purposes. Of particular interest are their effects on sexual function. Preclinical experiments in male rats showed an increase in fertility after administration of Cynomorium extract. In these tests, an increase in the weight of the testes and an increase in the number of spermatozoa and their viability were observed. Cynomorium plants offer a new approach to the treatment of human infertility, which is currently a major problem.

Glyphosate [N-(phosphonomethyl) glycine] is one the world's most widely used agricultural herbicide. It allows farmers to spray a planted field, generally before the crops have sprouted, killing weeds but not the crops that will grow there. GMO critics claim glyphosate is linked to autism, cancer, gluten allergies, ‘leaky gut’ syndrome and other disorders. Concerns about glyphosate’s possible health impacts increased in 2015 after the International Agency for Research on Cancer, a research arm of the World Health Organization, classified glyphosate as “probably carcinogenic”. The ecological risk assessment indicates that there is potential for effects on birds, mammals, and terrestrial and aquatic animals. A joint panel from the World Health Organization and the Food and Agriculture Organization of the United Nations issued an summary evaluation of glyphosate in May 2016, concluding it poses no cancer risks as encountered in food and does not impact our genes. Although the European Food Safety Authority declared the evidence on glyphosate’s carcinogenicity for humans to be “very limited”, there is still some doubt as to whether all the studies have been made "lege artis" or whether they have not even been falsified.

Within the alpha/beta hydrolase fold superfamily of proteins, the COesterase group (carboxylesterase type B, block C, cholinesterases…) diverged from the other groups through addition of an N-terminal disulfide bond and simultaneous increase in the mean size of the protein (1). This disulfide bond creates a large loop, which is essential for the high catalytic activity of cholinesterases through formation of the upper part of the active center gorge. In some non-catalytic members of the family, the loop may be necessary for heterologous partner recognition. The shuffling of this portion of protein occurred at the time of emergence of the fungi/metazoan lineage. Homologous proteins with this N-terminal disulfide bond are absent in plants but they are found in a limited number of bacterial genomes. In prokaryotes, the genes coding for such homologous enzymes may have been acquired by horizontal transfer. However the cysteines of the first disulfide bond are often lost in bacteria. Natural expression in bacteria of CO-esterases comprising this disulfide bond may have required compensatory mutations or expression of new chaperones. This disulfide bond may also challenge expression of the eukaryote-specific cholinesterases in E. coli. Recently , catalytically active human acetylcholinesterase and butyrylcholinesterase were successfully expressed in E. coli. The key was the use of a peptidic sequence optimized through the Protein Repair One Stop Shop process, an automated structure- and sequence-based algorithm toward expression of properly folded, soluble eukaryotic proteins with an enhanced stability (2,3). Surprisingly however, the crystal structure of the optimized butyrylcholinesterase variant expressed from bacteria revealed co-existing ‘close’ and ‘open’ states of the first disulfide bond. Whether the ‘open bond’ involves two cysteines (i.e., the bond never formed) or two half-cystines (i.e., the bond properly formed, then broke during the production/analysis process) cannot be inferred from the structural data. Yet, this observation suggests that this first bond is difficult to maintain in E. coli-expressed cholinesterases.

In this paper we have compiled and summarized the steps which manufacturers and clinical investigators need to undertake to perform a target population definition during the Health technology assessment process of medical device, namely external cardio stimulator (pacemaker). Based on available data using top-down approach we have defined target population for external cardiostimulator and estimated, that the size of the target population for external pacing will not exceed 16000 patients per year in the Czech Republic and is of comparable size with other states in the region.

Interaction between a host cell and pathogen is a permanent event and can have either adverse outcome leading to disease or great benefit for their mutual co-existence. Understanding pathological host–pathogen interaction is a prerequisite for unveiling the strategies of pathogens virulence. A number of methods exist today for deciphering and characterizing host–pathogen interaction. To increase their sensitivity and accuracy, these methods are commonly used in combinations, such as affinity purification and liquid chromatography–mass spectrometry analysis, cross-linking together with liquid chromatography–mass spectrometry analysis, or stable isotope labeling with amino acids in cell culture with affinity purification. In this review, we focus on study of the early interaction time interval when the pathogen binds and invades the host cell and activates sophisticated mechanisms to overcome the host defense barrier. We briefly describe the methods applied in identifying bacterial–host cell protein interactions while emphasizing these methods’ various strengths and weaknesses.

Introduction: Fluoroquinolones are a frequently prescribed class of antibiotics, which has been blacklisted in recent years because of a growing evidence of the connection with serious undesirable effects, infections Clostridioides difficile, and a connection with the occurrence of multiresistant strains.Methods: In the University Hospital Hradec Kralove in the course of the years 2009-2019, several antibiotic stewardship restrictive and educational interventions were performed by the Antibiotic Centre aiming to decrease quinolone antibiotics administration. The data of the consumption of quinolone antibiotics were retrospectively evaluated and correlated with the development of sensitivity and occurrence of multiresistance of selected bacteria in the hospital.Results: In the period under investigation, consumption of fluoroquinolone antibiotics significantly decreased (p<0.001) in 10 years by 71.8% to 26.7 DDD/1000 patient day. Sensitivity of Escherichia coli and Pseudomonas aeruginosa to fluoroquinolones in the period under investigation increased by 4.8% (respectively by 15%); on the other hand, sensitivity of Staphylococcus aureus decreased by 4.2% to 85.5% share of sensitive strains. The incidence of the multiresistant isolates Pseudomonas aeruginosa decreased by 8.1%, but the occurrence of ESBL-producing Klebsiella pneumoniae was increased in the period under investigation. The occurrence of methicillin-resistant Staphylococcus aureus did not show a stable trend and finally it was moderately increased by 2.9%.Conclusion: Implementation of programmes of antimicrobial stewardship for hospitalized patients resulted in a decrease and a rationalization of fluoroquinolone administration. The reduction of their consumption in our hospital resulted in a statistically insignificant increase in the sensitivity of Escherichia coli and Pseudomonas aeruginosa, but not Staphylococcus aureus.

Nerve agents (NAs) belong to family of organophosphorus inhibitors (OPIs) of acetylcholinesterase (AChE) enzyme. Although the use of highly toxic OPIs as chemical warfare agents is prohibited, they have been misused several times and thus still represents an emerging threat. For these reasons, the development of novel prophylactic agents and therapeutic intervention against NAs is still up-to-date and of high importance. Prophylactic administration of antidotes not only increases body's resistance to the effects of NAa, e.g. when operating at a contaminated environment after a terrorist attack, but also potentiates the subsequent antidotal therapy after exposure. Currently, pharmacological prophylaxis can be delivered either by protection of AChE against irreversible Inhibition, administration of commonly used antidotes in advance (i.e. oxime reactivators) or by the use of bioscavengers. The aim of the recent review is to highlight the current trends in prophylaxis and outline breakthroughs in prophylaxis based on reversible cholinesterase inhibitors like huperzine A or acridine derivatives.

Growing evidence of antibiotic-resistant pathogens is a serious medical issue that has to be addressed. Our antimicrobial research is focused on searching for novel small molecules that differ from the most clinically used antibiotics by chemical structure and mechanism. However, this fundamental research is like looking for a needle in a haystack. In addition, in vitro methods are time-consuming and expensive to screen large number of compounds in reasonable time. Off-target screening can represent a solution to find novel and effective antimicrobial agents that can eliminate these problems. Accordingly, molecular docking in the family of selected frentizole derivatives predicted their potential to inhibit bacterial nicotinate mononucleotide adenylyltransferase (NadD). This bacterial-essential specific enzyme has an important role in NAD metabolism. Thus, underlying mechanism of antimicrobials derived from frentizole would be interference with this biochemical process. Unfortunately, broth microdilution assay did not display any antimicrobial activity of tested compounds. On the other hand, herein we propose that off-target screening can facilitate searching for new drugs and that NadD could be a relevant target for antimicrobials.

Pregnancy related maternal mortality defines the state of maternal health. The increasing incidence of maternal death in the U.S indicates that this complex issue is not unique only to developing countries.  It is obvious that improvements are needed to reinsure appropriate healthcare for all pregnant women.  Without precise methodical data collection and data evaluation advancement of this important determinant of maternal health can’t be achieved.The aim of this paper is to provide contemporary perspective on pregnancy related maternal mortality.  In addition, this paper will discuss common ethnical disparities that underline maternal deaths.  Furthermore, this paper will address the confusing inconsistencies of maternal death terminology and variations in disease classification.  Finally, this paper will propose improvements in defining terminology and data collection that influence the understanding of pregnancy related morbidity.Quick Points - 1. Maternal mortality is a determining characteristic of existing maternal health in a given geographical region. 2. While it is impossible to completely eliminate all maternal deaths, preventable pregnancy complications    resulting in injury or death need to be reduced across the world. 3. Healthcare leaders need to work on identification of maternal mortality trends and development

In April 2005, an international advanced research workshop entitled, “Preparedness of Medical Systems: Guidelines for Mass-Casualty Situations” was convened in Haifa, Israel, under the auspices of NATO. Numerous specialists from various countries addressed the management of problems that arise during the hospital and pre-hospital phases of a medical response to mass-casualty situations, as well as the issue of preparedness for potential toxicological events. Methods for evaluating the quality of care provided during such situations were also discussed (1). In November 2009, the authors and their team organized the “NATO Advanced Training Course: Best Way of Training for Mass-Casualty Situations” for specialists from countries participating in the Partnership for Peace (PfP) and Mediterranean Dialogue (MD) programs; once again, the course was held in Haifa, Israel. The aim of the course was to inform its participants (all of whom were experienced protagonists in the field of emergency medical services and hospital management, or ministry of health officials, in their respective countries) about teaching and training methods for preparation for mass-casualty situations (2)...

The work describes system of preventive medical examinations in the Armed Forces of the Czech Republic, introduced in 1999, by comparison with preventive programs in civilian section. Detailed description of content of the examinations and anthropometric methods and news from 2017 shows advantages and disadvantages. Range of the examinations and problematics of participation of active soldiers are elaborated in discussion in cost-benefit ratio.

The interest and the increasing need for communication, exchange of experience and materials, training in diagnostics and research methods has led to the idea of creating an international scientific society focusing on tularemia. Tularemia meetings focus on fundamental, clinical, and applied research regarding any aspect of Francisella tularensis.  Research uncovers not only the biology of this fascinating bacterium, but also provides the basis for future development of treatments, preventive interventions, and disease diagnosis. Under the umbrella and with active participation of WHO, a group of scientists has met to develop this idea.

Background. Extracts from plant and/or animal tissues are frequently used in alternative medicine as drugs or food supplements. Such extracts may contain a complex of pharmacologically or physiologically active factors but frequently there exists no experimental confirmation as to precise mechanisms of action. This work aimed to verify if a long used bovine blood extract Imuregen registered as a food supplement has desirable effect on tumor cells.Methods. Two independent methodological approaches were used. Viability of cell cultures was evaluated using WST-1-based cell cytotoxicity assay. Cell growth was monitored in real time using xCELLigence cell analysis. Normal human adherent lung fibroblasts (NHLF) were used to represent non-tumor lung cells. A human non-small cell lung carcinoma cell line H1299 was used as a model of tumor cells.Results. Our study demonstrated a direct influence on viability of the H1299 tumor cell line (p < 0.005) and a cytostatic/cytotoxic effect of the bovine blood extract after 72h. of cultivation while leavingnon-tumor NHLF cell line unaffected. The extract (0.1 µg/ml and 1 µg/ml, resp.) also significantly affected the viability of irradiated H1299 tumor cell line (p < 0.005, Co, 4Gy) compared to non-tumor irradiated counterparts. In addition to the cytotoxic effect, the extract slightly modified the generation time of the cells and substantial differences between the effects on tumor and non-tumor cell lines were observed.Conclusion. The data presented here might suggest the extract intervenes into the proliferative cell cycle and subsequently influences the generation time of cells. Further analyses should be oriented toward the effects of animal tissue extracts on cellular systems defending against tumors and/or infections and intercellular communications that lead to influencing the fate of individual cell types.

N-Methyl-D-aspartate (NMDA) receptor belongs to the group of glutamate receptors, which are further divided into ionotropic and metabotropic. It affects synaptic plasticity and the development of neuronal synapsis in CNS. Ionotropic NMDA receptors are activated by glutamate, thereby flowing positively charged ions through the membrane along its concentration gradient. However, glutamate overload leads to excitotoxicity, due to high levels of Ca²⁺, which leads to cell death assocciated with neurodegenerative diseases. NMDA antagonists like dizocilpine reduce intracellular concentration of Ca²⁺ by modulating permeability of NMDA receptor channel. Dizocilpine act as a non-competitive NMDA receptor antagonist with anticonvulsant and anesthetic properties. Its therapeutic use in humans is limited due its numerous side effects, but it is experimentally used as an animal model of schizophrenia.

Giant hogweed (Heracleum mantegazzianum) is a member of the parsley or carrot family (Apiaceae). As its name indicates it is characterized by its size and may grow up to 4 meters in height. Giant hogweed is native to the Caucasus mountains and southwestern Asia and has been introduced to Europe, the United Kingdom, Canada and the United States as a garden curiosity. Because of its tenacious and invasive nature it soon becomes a pest within the ornamental garden and readily escapes. It has naturalized in many of the places where it was first introduced. All parts of the plant are poisonous and giant hogweed is toxic to livestock and humans. The danger of this contact-poisonous plant lies in the presence of phototoxic furocoumarins (psoralens). These substances cause disagreeable dermatitis with poorly healed blisters. Giant hogweed is dangerous for children and mainly if its juice penentrates the eyes.

This review provides information about blistering chemical warfare agents. The main focus lies on the sulfur mustard. The article summarizes the history of this agent from its discovery to the present, physicochemical properties, toxicokinetics, and the clinical picture of acute intoxication. Late effects of poisoning are discussed as well. The laboratory diagnosis of sulfur mustard exposure is an issue that is currently being discussed by many research groups worldwide. Current therapeutic approaches recommended by NATO are aimed at rapid decontamination and symptomatic treatment. In spite of all efforts, no potent and usable antidote has been found to prevent the devastating outcomes of the exposure. Therefore, efficient protection against sulfur mustard still consists of preventing the contact with organism.

Ionizing radiation (IR) induces various types of damage in the cellular DNA, of which the most deleterious are double strand breaks. Double strand breaks lead to activation of signaling cascade aiming to repair the damage or to transiently or permanently arrest cell cycle, and/or induce cell death. In the case of high doses of ionizing radiation with a high dose-rate (0.5-1 Gy / min) where the cell repair capacity is insufficient, cell death often occurs in response to double-strand breaks. The response to the radiation exposure depends on many factors such as the cell type, its proliferation activity, and p53 status. In tumor cells, cell death is associated primarily with apoptosis or mitotic catastrophe. In normal fibroblasts, cells accumulate in the G1 phase of the cell cycle and so-called premature senescence occurs after irradiation.In cells with functional p53 protein an increase in the p21 protein (cell division inhibitor) and accumulation of the cells in the G1 phase occurs. In the case of very low-dose rate (LDR), this accumulation is transient; after DNA damage repair, the cells continue to divide. Upon irradiation with higher doses at a LDR, accumulation in the G1 phase is irreversible; p16 protein is upregulated and the status of premature senescence is induced.  The same dose of radiation administered at LDRs results in more senescence than after an acute exposure.In the case of the use of IR for the eradication of tumor cells, the status of these cells is important in terms of p53 and proliferation. About fifty percent of tumor cells do not possess p53 protein or are mutant, and after irradiation they accumulate in the G2 phase and repair the IR-induced damage (e.g. HL-60 cells). In HL-60 cells (p53^-/- human promyelocytic leukemia), G2 phase accumulation occurs during irradiation with low dose rate, and their radioresistance increases if the cells are irradiated in the G2-phase. When the dose-rate is very low, the cells enter the mitotic cycle during irradiation, and because cels in mitosis are highly radiosensitive, apoptosis is induced and thus their radiosensitivity increases as well.

Personnel decontamination belongs to one of the crucial measurements performed to personnel's protection within hazard management after either employment of Weapons of Mass Destruction or leakage of Toxic Industrial Materials. Suitable personnel, technical and material conditions corresponding to current demands and trends are necessary to create its realization in this area. Knowledge gained within solution problems of personnel decontamination, casualty decontamination, immobile people decontamination, decontamination of personnel weapons, selected Individual Protective Equipment, personnel garments, accoutrements and other materials with the usage of modular elements are summarized in this paper. A conceptual proposal of solution of a mobile decontamination system for personnel decontamination is also stated in this paper.

Kim Jong-nam (10 May 1971 - 13 February 2017) was the eldest son of Kim Jong-il, leader of North Korea, and the estranged half-brother of North Korean dictator Kim Jong-un. From roughly 1994 to 2001, he was considered the heir to his father [1]. Following a series of actions showing dissent to the North Korean regime, including a failed attempt to visit Tokyo Disneyland in May 2001 by entering Japan with a false passport, he was thought to have fallen out of favour with his father. On 13 February 2017, Kim was allegedly murdered by two women who fled after the crime [2]. The murder was commited in Malaysia during his return trip to Macau, at the low-cost carrier terminal of the Kuala Lumpur International Airport [3]. Initial reports suggest that Kim Jong-nam was murdered by VX, a type of agent used in chemical warfare [4]. Toxicological tests showed the presence of VX in Kim's eyes and face [5]. What is the agent VX and could this toxic substance cause the death of Kim?