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A significant global problem of contamination of the aquatic ecosystem is the abundance of pharmaceuticals entering the aquatic environment as a result of their widespread use. An important group of drugs commonly detected in surface waters are non-steroidal anti-inflammatory drugs (e.g. ibuprofen and diclofenac). The aim of the present study was to evaluate the potentially negative effects of diclofenac and ibuprofen administered in feed on selected biochemical and haematological parameters of common carp (Cyprinus carpio). The test organisms were exposed to various concentrations of these non-steroidal anti-inflammatory drugs at concentrations of 20 and 2000 μg/kg for six weeks. The test substances were administered in the feed at a dose of 3 % of body weight. After the end of the exposure, blood was drawn with a sterile syringe from the tail vein into Eppendorf tube containing sodium heparin. One part of heparinized blood was used for analysis of selected haematological indices (red blood count, white blood count, haematocrit, haemoglobin). The second part of the heparinized blood was centrifuged (4 ⁰C, 10 min, 3,000 rpm) and the separated plasma was used for analysis of basic biochemical indices (glucose, albumin, total protein, cholesterol, LDH, ALT, AST, ALP, calcium, phosphorus, ammonium) using biochemical analyser Konelab 20i. Our results confirm that the substances tested pose a risk to aquatic organisms.

Benchmark dose (BMD) approach, as an advanced statistical methodology for dose-effect analysis in toxicological research (1) was used to quantitatively characterize in vivo efficacy of two experimental bispyridinium oximes K203 and K027, following promising findings on their low acute toxicity and potential to reactivate acetylcholinesterase (AChE) inhibited by organophosphorus (OP) pesticides and nerve agents in vitro and in vivo (2). Immediately after DDVP challenge (75% LD₅₀, s.c.), male Wistar rats were treated with oxime (0/1.25/2.5/5/25/50% LD₅₀, i.m.). Erythrocyte and diaphragm AChE activity was determined by Ellman's method 60 min after the treatment. Benchmark analysis was done in PROAST software ver. 65.5 (RIVM, The Netherlands). Derived BMD_er were K203 = 194 (153, 243) and K027 = 100 (81, 125) µmol/kg bw, BMD_diaph were K203 = 117 (56, 209) and K027 = 21 (10, 37) µmol/kg bw, indicating that oxime K027 induces the same effect size with 2 and 5.5-times lower dose compared to oxime K203 in erythrocites and diaphragm, respectively. Quantification of equieffective doses of oxime reactivators would enable more reliable definition of their therapeutic widths, which further contributes to better determination of therapeutic dosage regimens and, finally, increases the relevance of results obtained in animal models for the human population.

Uridine diphosphate sugar-utilizing glycosyltransferases (UGTs) are an enzyme superfamily that catalyzes glycosyl residues transfer from activated nucleotide sugars to acceptor molecules. In addition to various endogenous compounds, numerous xenobiotics are substrates of UGTs. As the glycosides formed are generally less active/toxic and more hydrophilic than aglycones, UGTs effectively protect organisms from potentially harmful xenobiotics. Therefore, increased UGTs expression and/or activity improves the protection of the organism and may contribute to the development of individuals that become more resistant to certain xenobiotics. While the function of UGTs in the resistance of human cancer cells to chemotherapy is now well known, other organisms and other xenobiotics have attracted much less attention. UGTs play an important role in defense against xenobiotics not only in humans, but in countless other organisms such as parasites, insects, and plants. Moreover, many recent studies clearly show the participation of UGTs in the resistance of nematodes to anthelmintics, insects to insecticides, weeds to herbicides as well as humans to various drugs (not only those used in cancer therapy but also in the treatment of epilepsy, psychiatric disorders, hypertension, hypercholesterolemia, and HIV infection). Nevertheless, although the contribution of UGTs to xenobiotic resistance in diverse organisms has become obvious, many pieces of information remain missing, for example with regard to the mechanisms of UGTs regulation.

The aim of the presented work was to evaluate the decontamination efficacy of newly developed decontamination agents based on surfactants with hydroxyl functional group.
Sarin and VX were selected as representative nerve agents (NA). The ability to accelerate the catalytic hydrolysis of the NA was assessed by the pH value measurement using an automatic burette. The hydrolysis of NA in a contaminated solution leads to a decline of pH value due to the formation of O-alkyl methylphosphonic acids (MPAs). The ability of tested surfactants to penetrate through the skin and their rinsing effectivity was observed using modified Franz-type of glass diffusion cells and ex vivo dermatomed porcine skin as a model membrane. The amounts of surfactants penetrated into the receptor fluid after application on the skin surface were determined by HPLC with fluorescent detection. The solutions of surfactants were used to rinse the contaminated skin. Simultaneously, the same solution was contaminated by corresponding amount of NA to simulate the situation when 100 % of a contaminant is rinsed off. The MPAs in the rinsing fluid and NA penetrated into the receptor fluid were determined by HPLC-MS. The decontamination efficacy of the tested solutions was expressed in % of an agent washed away by the rinsing fluid.
All of tested newly synthesized compounds had better hydrolytic activity compared to the commercially available surfactant. Their penetration through the skin was not observed. The rinsing efficacy of all tested solutions was comparable.

Depressive disorder is a serious mental illness whose incidence is constantly increasing in developed countries. About 20% of pregnant women suffer from maternal depression. Both untreated and treated maternal depression represents risk factor for development of fetus and newborn. The maternal hormones, such glucocorticoids, have been reported to be altered in response to a maternal challenging environment. These molecules cross the placenta and reach the fetus, altering the neurodevelopmental pathways in the fetus that may affect the proper brain functioning, leading to an increased risk for neurodevelopmental disorders. Antidepressants used to treat maternal depression represent also a risk factor for fetal and neonatal development. The results of our experimental studies have been shown beneficial effects of selected antidepressants on neurogenesis, synaptic plasticity and behavioral variables on rat offspring. However, there are many controversy on effects of maternal depression and antidepressants on fetal and early postnatal development. Therefore, it is highly topical to investigate their potential unfavorable as well as beneficiary effects on healthy development of the offspring.

Multidrug resistance-associated protein 2 (Mrp2) is the crucial transporter for the biliary secretion of anionic compounds. The genetically determined absence of this transporter may occur in humans, causing conjugated hyperbilirubinemia and increased risk of intrahepatic cholestasis of pregnancy (ICP). The ICP threatens fetuses with adverse pregnancy outcomes due to increased bile acids (BAs) plasma concentrations. This study aimed to characterize BAs metabolomics in Mrp2 deficiency and ICP. Cholestasis was induced in Mrp2-deficient and wild-type rats by ethinylestradiol as a model of ICP. BAs were analyzed in plasma, bile, and stool to describe their metabolomics together with liver and intestinal enzymes and transporters responsible for BAs enterohepatic recycling. Mrp2-deficiency reduced the biliary secretion of BAs and increased their plasma concentrations in part due to increased BAs efflux from hepatocytes to the blood via upregulated Mrp3 and Mrp4 transporters. The intestinal BAs reabsorption was also reduced in these rats due to downregulated ileal sodium/bile acid cotransporter. The activation of constitutive androstane receptor-nuclear factor erythroid 2 related factor 2 pathway by accumulating bilirubin might be responsible for observed changes in BAs metabolomics in Mrp2-deficient rats. The plasma concentrations of BAs were further increased by ethinylestradiol administration in Mrp2-negative rats due to reduced BAs uptake and increased hepatocyte efflux via reduced Slco1a1 and upregulated Mrp4 transporters. Our results confirmed the hypothesis that impaired Mrp2 transporter predisposes to increased plasma concentrations in estrogen-induced cholestasis due to complex changes in liver transporting proteins. We, therefore, recommend regular monitoring of BAs in the plasma of pregnant women with conjugated hyperbilirubinemia.

The goal of this project is to create algorithm and software solution for prediction of drugs’ side effects. The algorithm is based on calculations of interactions between active substances and known macromolecules.
Methods of molecular docking and reverse molecular docking are used there. Each exanimated drug substance is docked into binding site of each macromolecule of sc-PDB database while the interaction between them is calculated. A set of decoys is selected from the ZINC database based on chemical properties. Decoys are docked into binding site of each macromolecule as well as exanimated drug substances. The docking results of exanimated substances and decoys are compared to determine the specificity of interactions. These methods are implemented using AutoDock Vina. All of docking interactions are analyzed by R software and the list of resulting macromolecules are released. The active drugs substances can be a substrate, inhibitor, or inducer of resulting macromolecules and they are suitable for in vitro testing.
The software solution is designed as a public service accessible by a web browser.

Tuberculosis (TB) is one of the top 10 causes of death worldwide from a single infectious agent. The World Health Organization (WHO) estimated 10 million new cases and 1.5 million deaths from TB in 2020 (1). Some strains of mycobacteria causing TB show numerous resistances to first-line drugs (isoniazid /INH/ and rifampicin) and to second-line drugs (fluoroquinolones, amikacin, bedaquilin, etc.). The development of new anti-TB drugs with new mechanism of action is necessary to improve TB therapy and to fight against resistant TB as well.
We screened our in-house library of small molecules for their therapeutic potential and identified compound K1297 with good anti-TB activity with minimum inhibitory concentration MIC₉₉ = 4 μM against H₃₇R_v strain (for comparison, MIC₉₉ (INH) = 0.5 μM). The main structural motif of this molecule is purine scaffold, which was modified and functionalized to elucidate the structure-activity relationships (SAR) and to identify derivatives with low toxicity and higher efficiency than the initial hit K1297. The effect of individual structural fragments on in vitro antimycobacterial activity, toxicity and selectivity of action have been evaluated. Finally, derivatives with optimized activity/toxicity ratio have been found and their pharmacokinetic profile and in vivo efficacy will be evaluated.

Mercury exists in the environment as elemental, metallic mercury, inorganic mercury and organic mercury.  Elemental and inorganic mercury released into the atmosphere from combustion of fossil fuels, mining, smelting and various industrial activities. In the aquatic environment is mercury deposited to sediments where is transformed into the main organic form methylmercury. Mercury methylation occures in the aquatic environment due to microorganisms metabolism as sulfite reducing bacteria.  The toxicity of mercury in humans or animals depends on its chemical form. Elemental mercury is volatile, gastrointestinal absorption of inorganic mercury is between 10 - 30% range. Methylmercury is the most toxic form of mercury. In comparison with the inorganic form, methylmercury is absorbed from more than 80 % in the gastrointestinal tract, than is widely distributed to all tissues, although the largest deposition occurs in the kidney. The enterohepatic cycle results in a long half-life for this compound compared to inorganic mercury. Methylmercury is able to cross the blood-brain and the placental barriers,  mainly affects the central nervous system and is harmful to the nervous system development of the fetus.
The greatest risk of human exposure to mercury comes from food chain. Various authorities, such as United States Environmental Protection Agency (USEPA),  the Joint Expert Committee on Food additives (JECFA) of the Food Agriculture Organization (FAO), World Health Organization (WHO) and European Food Safety Authority (EFSA),  have established a reference dose for human consumption, such as Provisional Tolerable Weekly Intake (PTWI) for methylmercury.
Our study were focused on two year report from Rapid Alert System for Food and Feed (RASFF) and evaluation of  various fish species from market chain exceeded established tresholds by the Commission Regulation (EC) No. 1881/2006 of 19^th December 2006 setting maximum levels for certain contaminants in foodstuffs. According to this study, in 2017 and 2018 y., 113 cases of exceeding the Hg content limit in fish and seafood products were reported. The most commonly reported fish is swordfish (Xiphias gladius), blue shark (Prionace glauca) and mako shark (Isurus oxyrinchus).

Coronavirus disease COVID-19 is highly infectious disease caused by SARS-CoV-2 virus as a novel coronavirus led to pandemic. Due to fast transmission COVID-19 has become a global problem. The virus is spread by aerosol from infected people and persists in the air for a long period. SARS-CoV-2 affects the lungs, but it can also affect digestiv or cardiovascular systems, can attact the brain, damage vessels and can lead to neurological manifestation. COVID-19 has several clinical symptoms and can lead to multiorgan dysfunction and death. On the other hand, in some infected persons COVID-19 can take place asymptomatic. Due to the risk of rapid spread of COVID-19, the early prediction of the onset of the epidemic is important. The Water Based Epidemiology (WBE) is an effective tool for monitoring the number of infections and can serve as a tool to monitoring various human activity including health status of population in given area. One of the advantage of WBE in last pandemic is their capability to reveal the outbreaks at an early stage, including presymptomatic or asymptomatic transmission of SARS-CoV-2. The use of WBE is based on the principle of viral shedding in stool samples and on the detection of SARS-CoV-2 viral mRNA by PCR method in wastewater samples. On the other hand, some non-specific markers from COVID-19 infected persons can also be used in WBE. Viral infections are associated with inflammation. Neopterin, a pteridine derivative, is produced in the metabolism after some stimulus. Neopterin was found in urine and other body fluids, as blood serum, cerebral spinal fluid in COVID-19 infected persons in high levels. Through urinary excretion, neopterin was detected in wastewater samples. The other markers, as toxin-like peptides, similar or identical to toxic components of venoms from animals, such as conotoxins, phospholipases, phosphodiesterases, zinc metal proteinases, and bradykinins, were identified in blood plasma, urine and faecal samples from COVID-19 patients. These markers, including neopterin, can be potencially useful in WBE as markers of rapid prediction of the onset of the epidemic. The early detection of the presence of SARS-CoV-2 within communities can also give healthcare authorities time to prepare for potential outbreaks and time to prepare measures to protect population.

Cadmium is a toxic transition heavy metal commonly found in the environment and its occurrence is mainly conditioned by agricultural and industrial production. Increased exposure to cadmium, especially because of its accumulation in organisms, causes damage of kidney, liver, and bones. Intracellularly, there are proteins, metallothionines, that are actively involved in the detoxification of cadmium by its uptake. In response to increased ROS production after exposure to cadmium, the Nrf2 protein, which modulates glutathione synthesis, is activated (1). The activation rate of Nrf2 protein depends on the concentration of cadmium in a certain time interval (2).
In our work, we focused on testing selected concentrations of cadmium chloride (5-100 µM) in SH-SY5Y neuronal cells in vitro. To describe the cellular toxicity, we used a spectrofluorimetric method to determine the intracellular concentration of glutathione (GSH) using monochlorobimane (3) in selected time intervals (1-24 hours). The results suggested that especially at concentrations under 50 µM CdCl₂, there is a transient increase in intracellular GSH levels relatively to untreated cells. A significant increase in GSH concentration up to 150% was detected in 5-50 µM CdCl₂ treated cells after 24 hours.

Untreated depression during pregnancy has wide spectrum of negative effects on the mother and the child. Recently, the rising numbers of depression in pregnant women were followed with a steep rise of antidepressant use. Mirtazapine is an atypical antidepressant generally considered to be safe to use during pregnancy and lactation.
Aim of our study was to investigate the effect of maternal stress and effect of perinatal mirtazapine treatment on the behavior of rat offspring.
Adult female Wistar rats were randomly assigned to stress and control groups and subjected to three weeks of chronic unpredictable stress schedule and mated with males. From gestation day 10 they were administered mirtazapine (10mg/kg/day) or vehicle until weaning via cookie. Offspring of experimental dams was subjected to battery of behavioral testing. Our results generally show that the offspring of stressed mothers had elevated anxiety-like behavior in different tests for anxiety with different severity depending on the age and sex of the offspring, while mirtazapine treatment generally reduced the negative effect of stress. In forced-swim test the adolescent offspring from stress+mirtazapine groups exhibited lower depression-like behavior compared to control groups. In Y-maze test all experimental groups of adolescent females had lowered spontaneous alternations compared to control, suggesting worsened exploration and spatial memory.
Further investigation is needed to assess the safety of mirtazapine use during pregnancy and post-partum period.

Insufficient supply of oxygen to the fetus (prenatal hypoxia) is one of the impacts capable to disrupt the pre- and postnatal development of an affected individual. Even though antioxidant trials largely turned out to be negative, research is still ongoing to find an optimal antioxidant drug to prevent or treat pregnancy related complications. Focus has been on more selective antioxidants and has investigated intracellular sources of oxidative stress during pregnancy. Our study aimed to assess the use of L-Ergothioneine (ERG) as potential new therapy for prenatal hypoxia. ERG serves as an antioxidant and cellular protectant against various kinds of reactive oxygen species.
Pregnant Wistar rats were subjected to hypoxia (10,5% O₂) on gestational day (GD) 20 for 12h. E was administered p.o. in dose 8 mg/kg/day (E1) or 35 mg/kg/day (E2) on GD 6-21. ERG in both doses delayed motor development but facilitated sensory development of hypoxic pups and normalized anxiety- and depression-like behavior of hypoxic males in adulthood. Moreover, E2 normalized the cognitive capacity of hypoxic males. E2 alone, however, delayed sensory development and induced anxiety-like behavior of intact animals. ERG (esp. in dose 35 mg/kg) had a partial compensatory effect on the behavior of rat offspring in adulthood that indicates its possible use in the therapy of behavioral impacts of prenatal hypoxia. Its preventive use, however, does not seem acceptable due to the negative effect of E2 on the behavior of intact animals in our study.

Bisphenols (e.g. bisphenol A, BPA), are chemical compounds used in manufacturing of plastics and polluting the environment worldwide in nanomolar concentrations. Although the direct toxic effects of "environmentally relevant" concentrations are controversial, concerns are associated with their action as chemical disruptors because their structure is similar to estrogens. Several studies reported that BPA may cause adverse effects in humans and animals (1), including an interference with cardiac differentiation (2). Based on these concerns, BPA was gradually replaced during last decade with “next generation” bisphenols. However, little is known about safety of these BPA derivatives. Traditional in vitro models used in cardiovascular research are unable to reliably study the toxicological potential of bisphenols. Therefore, our aim is to develop a reproducible protocol for differentiation of H9c2 cells, a myoblast cell line derived embryonic rat heart tissue, to cardiac muscle phenotype based on previously published protocols (3). We have started a comparison of several protocols based on varying concentration of fetal bovine serum, glucose and all-trans retinoic acid in cultivation media, and the duration of cultivation in differentiating media, with following morphology and expression of tissue-specific markers to describe resulting phenotype. The toxicity of bisphenols is compared between parent and differentiated phenotype, and finally the possible influence of bisphenols on the cardiac differentiation process or cellular stress markers is assessed.

Nerve agents are organophosphorus compounds (OPs) with very potent toxicity due to their irreversible inhibition of the essential enzymeacetylcholinesterase (AChE; EC 3.1.1.7), which is primarily important in the control of neurotransmission in synapses. The related enzyme butyrylcholinesterase (BChE; EC 3.1.1.8) is inhibited by OPs aswell. Compounds with an oxime group act as reactivatorsof the inhibited AChE by the nucleophilic displacement of OP moiety from the enzyme’s catalytic serine and are used as a pharmacological treatment after OP poisoning. However, restoration of the AChE activity is directly related to the oxime structure and standard oximes in medical practice are not equally effective for various OPs (1). It was demonstrated that the chlorine substituent reduce the pKa of the oxime group compared to the non-substituted analogues and result in the higher formation of oximate anion which can be correlated to their increased reactivation ability (2). In this work, the synthesis and thorough evaluation of fluorinated and chlorinated oximes is presented. Firstly, their stability and oximate forming properties (pKa) were determined. Further, the evaluation comprised testing for affinity for human recombinant AChE and human purified plasmatic BChE, the oxime’s efficacy in reactivation of sarin-, cyclosarin-, VX-, tabun-inhibited AChE or BChE. Finally, the antidotal potential of the lead halogenated oxime was tested in mice exposed to sarin and cyclosarin (3).

The history of the use of toxic substances goes back to the distant prehistory of mankind. Over time, man has acquired and perfected the knowledge gained in his life and gradually passed it on from generation to generation. The authors recall the basic milestones before and during the emergence of chemical weapons, focusing on the widespread use of chemical weapons during the First World War. However, other armed conflicts are also mentioned, when chemical weapons were used as an important means of warfare (for example, Vietnam War, the Iraq-Iran War, etc.).
Selected specific cases of misuse of chemical warfare agents for terrorist purposes are also underlined and briefly described. Chemical warfare agents as the main content of chemical weapons have a high toxic potential (basically super-poisons) and their misuse for terrorist attacks is quite high.
The next part of the thesis presents some important acts of international law, such as the so-called Geneva Protocol from 1925 and other legal activities of an international nature and impact. Subsequently, the main principles, requirements and obligations of the ban on chemical weapons under the important international agreement Chemical Weapons Convention 1993 (1), which entered into force in April 1997, are discussed in detail.
National legislation, Czech national law (2) and its implementing decree (3) are presented in detail in the following part of the article. The authors of the article present a brief analysis and evaluation of the current situation in the researched area of the prohibition of chemical weapons. At the same time, in the form of an academic discussion, they present some of their own proposals and recommendations for improving the current situation in the field of chemical weapons bans, focusing on the Czech Republic.

The level of contamination of the aquatic environment with residues of drugs as metoprolol, enalapril and metformin is constantly increasing. One of the reasons is the increasing prescribes and uses of these drugs, second is imperfect purification in wastewater treatment plants. Since the pharmaceuticals are entering water bodies continuously, they represent a potential risk for non-target aquatic biota. In our study, the toxicity of metformin, metoprolol and enalapril on zebrafish (Danio rerio) embryos in five different concentrations was tested. The acute toxicity test was performed according to OECD Guideline No. 236: Fish Embryo Acute Toxicity Test. The aim of this experiment was to study toxic effects of typical drugs used for treatment of diseases of affluence as diabetes, cardiovascular diseases and hypertension on fish early life stages. Metformin is the most common drug used to treat type II. diabetes, metoprolol and enalapril are used to treat diseases of the cardiovascular system and hypertension. The results showed that the tested substances had a negative effect on hatching of embryos at all tested concentrations and also they have influenced mortality and heartbeat.

Alzheimer’s disease (AD) is a progressive brain disorder with characteristic symptoms and several pathological hallmarks. The concept of “one drug, one target” has not generated any new drugs since 2004. The new era of drug development in the field of AD builds upon rationally designed multi-target directed ligands that can better address the complexity of AD (1). Herewith, we designed ten novel derivatives of 2-propargylamino-naphthoquinone. The biological evaluation of these compounds includes inhibition of monoamine oxidase A/B, inhibition of amyloid-beta aggregation, radical-scavenging, and metal-chelating properties. Some of the compounds possess low cytotoxicity profile with an anti-inflammatory ability in the lipopolysaccharide-stimulated cellular model. All these features warrant their further testing in the field of AD (2).

The number of successful drug development projects has been stagnant for decades despite major breakthroughs in chemistry, molecular biology and genomics. Unreliable translatability of preclinical in vitro and in vivo models has been identified as the cause of most failure. Organotypic and microphysiological culture of primary human cells has emerged as a set of promising tools for preclinical drug development to narrow this translation gap. In this talk I will provide an overview of our recent efforts in developing 3D human tissue cultures and microfluidic models for both efficacy and safety assessments. In addition, the talk will present recent use cases where the use of such organotypic cultures has had direct impacts on market authorizations.

Bile acids (BAs) play a significant regulatory role in the pathophysiology of non-alcoholic steatohepatitis (NASH). The present study evaluates the modulation of BAs homeostasis by carvedilol, a nonselective blocker beta adrenoreceptor that is routinely used to treat cardiovascular complications accompanying NASH. NASH was induced in mice by a continuous 24-week high-fat diet (HFD) with glucose/fructose in drinking water. At week 21, individual groups of animals received carvedilol (10 mg/kg/day, p.o.) for three weeks. Biochemical and histological analysis has shown the effectiveness of a high-fat diet in inducing NASH. The spectrum of bile acid was analyzed in bile, stool, and plasma by the LC-MS method and the molecular determination of BAs-related enzymes and transporters. Carvedilol significantly increased plasma concentrations of BAs in healthy mice via downregulation of Ntcp and Bsep transporters. Carvedilol did not significantly affect net BAs plasma concentrations or BAs biliary and fecal excretions in animals with developed NASH. However, it shifted spectra of BAs toward more hydrophilic and less toxic αMCA and HCA. Carvedilol also significantly reduced liver fibrosis in NASH mice and in vitro suppressed profibrogenic response in human hepatic stellate cells. Our results suggest the hepatoprotective effect of carvedilol in NASH and support using this agent as a part of cardiovascular regimens in patients with metabolic syndrome and a high risk of NASH development.

Organophosphorous compounds (OPs) such as nerve agents or pesticides are irreversible inhibitors of cholinesterases, namely Acetylcholinesterase (AChE) and Butyrylcholinesterase (BChE), causing cholinergic crisis (1). While inhibition of AChE can be lethal, inhibition of BChE has no adverse effects. Therefore, BChE can be used for scavenging OPs before it reaches AChE in CNS. BChE itself has no catalytic activity, but by joint administration of BChE and reactivator we can establish pseudo-catalytic bioscavenger (2). Reactivators cleave the OP moiety from the enzyme by making a covalent bond with it. Reactivators of AChE are already widely used (eg. pralidoxime, asoxime) but there are few disadvantages. Firstly, there is no broad-spectrum reactivator. Second problem is that they have low ability to pass the blood-brain barrier (BBB) due to their double-charged structure. Moreover, when the OP-ChE complex is dealkylated (so called “aging” of ChE), it is no longer possible to reactivate. That is why nowadays the research is focusing to development of reactivators of BChE as well (3).  Promising results were obtained for the novel “K-oximes” K027, K048 and K203. The aim of this research is synthesis and in vitro evaluation of monoquaternary analogues of oxime K203 and observation of the effect of charge on physicochemical properties of compounds and on biological activity.

Pistacia lentiscus L. (PLL) is a wild-growing shrub from the Anacardiaceae family that occurs naturally in the Mediterranean. It has been used in traditional medicine for its many effects since the days of ancient Greece (1). PLL plant and processed products have been largely employed as oral antiseptic, anti-inflammatory, analgesic, and healing agents (2). Today, the scientific interest in these edible and not-edible parts of PLL is wide-spreading, as some studies underlined the potential benefit against inflammation and infections (3). The aim of our work is to find out more details about biological activity of essential oil and aqueous extract prepared from leaves of wild occurring PLL plants growing in North Sardinia. The cytotoxicity of not only the pure essential oil but also of the nanoemulsions with PLL oil, and aqueous extract were tested on three oral cell lines (gingival fibroblasts, periodontal ligament fibroblasts, and dysplastic oral keratinocytes). The viability of human oral cells was the most diminished by lecithin nanoemulsion, less by aqueous extract, and pure essential oil had the lowest influence on the viability – it was non-toxic up to the concentration of 100 μg PLL/ml medium. The anti-inflammatory activity was measured by cyclooxygenase and lipoxygenase inhibition. PLL essential oil showed the capacity to inhibit COX1/2 more than LOX. In conclusion, PLL essential oil is not cytotoxic for oral cell lines and show an in vitro anti-inflammatory activity.

A cascade of events, including platelet aggregation, cytokine release, inflammation, fibroblast proliferation, angiogenesis and re-epithelialization, occurs in a healing wound. These processes are necessary for the proper course of healing, scar formation and remodeling.
To accelerate healing of skin wounds, novel advanced, porcine and equine collagen/tencel based dressings, were fabricated. Collagen plays a pivotal role in each phase of healing due to its chemotactic role. It attracts different types of cells such as fibroblasts and keratinocytes to the wound. This supports angiogenesis and re-epithelialization. To monitor biological efficacy, dressings were tested on an acute excision wound model in a laboratory rat. The wound size was recorded at 2, 7 and 14 days after surgery. Selected biomarkers were measured in the tissue - levels of proinflammatory cytokine IL-6, growth factors TGF beta and VEGF. Presence of inflammatory infiltrate, granulomatous reaction and re-epithelialized area were evaluated histologically.

Novichoks are a set of militarily abused substances from the group of nerve agents. The mechanism of their action is the covalent binding to Ser203 of acetylcholinesterase and inhibition of acetylcholine degradation. Any in vitro or in vivo experimental studies of novice-inhibited acetylcholinesterase reactivation have not been published yet (1). However, the possibilities of reactivation can also be investigated computationally. For this study, we used the methods of molecular docking in combination with molecular dynamics.
We hypothesized that reactivation of novichok-inhibited acetylcholinesterase is not possible for steric reasons. In the molecular modeling study, we investigated whether the oxime group of reactivators can get close enough to the active site to make the nucleophilic attack. Calculations were performed for commercial oximes (HI6, obidoxime, pralidoxime etc.) and also for new experimental ones, in total 60 reactivators.
We have found out that some of the reactivators can adopt a position close to the active site and the nucleophilic attack is possible. Our original hypothesis was refuted.

Both molecular docking and molecular dynamics was used to visualise the active or blocked site of AChE, and to determine affinity values in silico modelling. Selection of 60 ligands (including commercially available reactivators, e.g. trimedoxime, asoxime) from peer-reviewed articles (2) were docked into into proximity of AChE-A230 complex bond using software AutoDock Vina (v. 1.1.2). The most promising 32 ligands docked in AChE were evaluated by molecular dynamics (GROMACS 2020.4 software).
Evaluation of specified simulations using Visual Molecular Dynamics (VMD) software has shown that the closest distance between the oxime group of the Z03-labeled ligand and the phosphorus of A230 was 3.14Å proposing theoretical successful reactivation regarding the near–attack conformation (NAC) criterion. The results of this study provide a rational basis for the synthesis of proposed reactivators and their consecutive in vitro evaluation.

Tuberculosis (TB) is a transmissible infectious disease caused by the intracellular bacteria, Mycobacterium tuberculosis (MtB), (1) which is currently one of the top 10 leading causes of death in low and middle-income countries (2). During 2020, 5.8 million patients were diagnosed with TB, 1.5 million of them died. In that year, 150 thousand patients were infected with drug-resistant TB strain.1 M. tuberculosis can quickly develop resistance against anti-TB regimens, and if not cured adequately, it can evolve into MDR-TB (multidrug resistant TB) and XDR-TB (extensive-drug resistant TB) (1). Therefore, there is a critical need to develop new chemotherapeutic agents with new mechanism of action to fight against a growing public health menace caused by cross-resistant TB strains (3).

We screened our in-house library of small molecules for their potential antimycobacterial properties identifying compound K1827 with excellent antimycobacterial in vitro activity against M. Kansasii (MIC₉₉ = 0.25 μM, which is more than 100 times more efficient that INH) and moderate activity against M. tuberculosis H37Rv (MIC99 = 32 - 64 μM, for comparison MIC99 of INH = 0.5 μM). This core scaffold of K1827 is pyrimidine that was functionalized to develop derivatives with higher activity against M. tuberculosis, better safety profile, and to determine the structure-activity relationships in the series. The effect of individual structural fragments on in vitro antimycobacterial activity, toxicity and selectivity of action have been evaluated and will be discussed within our contribution.