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Dietary exposure to aflatoxin B1(AFB1) is harmful to the health and performance of domestic animals. The hepatic cytochrome P450s (CYPs), CYP1A1 and CYP2A6, are the primary enzymes responsible for the bioactivation of AFB1to the highly toxic exo-AFB1-8,9-epoxide (AFBO) in chicks. However, the transcriptional regulation mechanism of these CYP genes in the liver of chicks in AFB1metabolism remains unknown. Dual-luciferase reporter assay, bioinformatics and site-directed mutation results indicated that specificity protein 1 (SP1) and activator protein-1 (AP-1) motifs were located in the core region −1,063/−948, −606/−541 of the CYP1A1promoter as well as −636/−595, −503/−462, −147/−1 of the CYP2A6promoter. Furthermore, overexpression and decoy oligodeoxynucleotide technologies demonstrated that SP1 and AP-1 were pivotal transcriptional activators regulating the promoter activity of CYP1A1and CYP2A6. Moreover, bioactivation of AFB1to AFBO could be increased by upregulation of CYP1A1and CYP2A6expression, which was trans-activated owing to the upregulalion of AP-1, rather than SP1, stimulated by AFB1-induced reactive oxygen species. Additionally, nano-selenium could reduce ROS, downregulate AP-1 expression and then decrease the expression of CYP1A1and CYP2A6, thus alleviating the toxicity of AFB1. In conclusion, AP-1 and SP1 played important roles in the transactivation of CYP1A1 and CYP2A6 expression and further bioactivated AFB1to AFBO in chicken liver, which could provide novel targets for the remediation of aflatoxicosis in chicks.

ABSTRACTBackgroundAdherence to Multiple Sclerosis (MS) treatment is considered one of the crucial factors for ensuring optimal clinical outcomes. Research has shown that the use of self-injector devices improves patient compliance with treatment. Therefore, the main purpose of this study is to evaluate the ease of use of RebiSmart® 2.0 in clinically isolated syndrome/relapsing-remitting MS patients during 12 months treatment period.MethodsA total number of 290 subjects entered into data collection; 249 (86%) of them completed the whole 12 months study period. The primary endpoints and the secondary endpoints were assessed by the User Study Questionnaire. Adherence data were retrieved from RebiSmart® 2.0 (Menu – Dose History) on the respective patient’s visit. Outcome measures also included Expanded Disability Status Score, Kurtzke Functional Systems, and Modified Social Support Survey, Modified Social Support Survey-5.ResultsThis study demonstrated a very high proportion (>95%) of patients with a positive rating of the overall ease of use and the overall convenience of RebiSmart®. The proportion of patients with a positive rating of the ease of use by individual domains and the functions of RebiSmart® were also high (>80%).ConclusionThe findings demonstrate a very good perception of the usability of the device by patients overall and in its individual functions.

The use of nerve agents as warfare and in terrorist acts has drawn much attention from the governments and societies. Such toxic organophosphorus compounds are listed in Chemical Weapons Convention as Schedule 1 chemicals. The discussion about the chemical identity of the elusive Novichok agents, more potent compounds than best known G- and V-Agents, which have been implicated in recent rumorous assassination plots, clearly demonstrating the importance of the matter. Furthermore, accidents with pesticides or misuse thereof have been a pressing issue in many countries. In this context, the continued development of novel cholinesterase reactivators, antidotes for organophosphorus poisoning, a rather restricted class of pharmaceutical substances, is warranted. Testing of novel candidates may require use of actual nerve agents. Nonetheless, only a few laboratories comply with the requirements for storing, possession and manipulation of such toxic chemicals. To overcome such limitations, nerve agents’ surrogates may be a useful alternative, as they undergo the same reaction with cholinesterases, yielding similar adducts, allowing assays with novel antidote candidates, among other applications.

Current demographic trends indicate that there is a growing number of older population groups worldwide, which is associated with an increase of chronic neurological disorders such as Parkinson’s disease that burdens the country’s healthcare system. Therefore there is an urgent call for developing efficient strategies which could reduce the healthcare costs and meet the demand of older people affected by these chronic neurological diseases at affordable cost. One of such approaches is the exploitation of a new emerging platform in the form of Internet of Things (IoT), which takes advantage of the connection of any physical object, for example a smartphone, to the Internet. The purpose of this study is to explore the use of IoT in the management of Parkinson’s disease (PD), specifically in its assessment, diagnostics, and treatment. The methods used in this study include a literature review of available sources found in the world’s acknowledged databases Web of Science, Scopus, PubMed, and ScienceDirect, as well as the methods of comparison and evaluation of the findings from the selected studies. The findings show that IoT may serve as an appropriate healthcare platform. IoT seems to be efficient, cost-effective and affordable approach in the management of chronic neurological disorders such as PD. However, more research has to be done by conducting more randomized controlled trials with larger samples of subjects in the area of the use of IoT in PD, as well as in other chronic neurological diseases.

Background: In the sense of Act No. 123/2000 Coll., as amended (hereinafter referred to as “the Act”), a medical device is understood to be a wide range of resources, especially medical equipment. To implement innovative technologies in practice, it is becoming extremely important to be cost-conscious and effective. The aim of the article is to use an ultrasonographic device case study in a selected hospital to show the possibility of solving the use effectiveness of medical devices.Methods: Within the first step, a summary of the use of ultrasonographic devices is developed in terms of performance number and time. Also, a summary of all costs for the last 5 years has been created. The analyzed ultrasonographic device set is evaluated in terms of activity indicators, profitability, and Du Pont decomposition. Revenues from the operation of individual instruments and payroll productivity are taken into account. All of this is evaluated in the context of the requirements of the department and the spectrum of ultrasonographic devices.Results: The results show that the economic evaluation of device use efficiency, comparing the requirements of the department and spectrum of the devices, suggests a major revision in use of these devices and savings.Conclusion: The new design of the most profitable system differs significantly in the arrangement of individual ultrasonographic devices. The benefit of the study is not just a newly designed organization-specific arrangement, but it can be perceived as a modeling approach that can be used to analyze other sets of medical technology.

An innovative amperometric immunosensor has been developed to detect antibiotic colistin from the chicken liver. Colistin is a antibacterial peptide that has been barred for human consumption, but it is being commonly used as a veterinary drug, and as a feed additive for livestock. In the present work, an immunosensor was developed by immobilizing an anti-colistin Ab onto the CNF/AuNPs surface of the screen-printed electrode. The sensor records electrochemical response in the chicken liver spiked with colistin with CV. Additionally, the characterization of electrode surface was done with FE-SEM, FTIR, and EIS at each step of fabrication. The lower LOD was 0.89 μgKg−1, with a R2of 0.901 using CV. Further validation of the immunosensor was conducted using commercial chicken liver samples, by comparing the results to those obtained using traditional methods. The fabricated immunosensor showed high specificity towards colistin, which remained stable for 6 months but with a 13% loss in the initial CV current.

Nerve agents are organophosphates acting as potent inhibitors of acetylcholinesterase (AChE), the enzyme responsible for the hydrolysis of acetylcholine and, consequently, the termination of the transmission of nerve impulses. The inhibition of AChE by an organophosphate can be reversed by a nucleophilic agent able to dephosphorylate a serine residue in the active site of AChE. In this sense, the oximes are compounds capable of removing the nerve agent and reactivate the enzyme. Here, we have applied a methodology involving theoretical docking and Quantum Mechanics/Molecular Mechanics, using the softwares Molegro®and Spartan®, to evaluate the kinetic constants of reactivation and the interactions of the oxime BI-6 with AChE inhibited by different organophosphorus compounds in comparison to in vitrodata. Results confirm that this method is suitable for the prediction of kinetic and thermodynamic parameters of oximes, which may be useful in the design and selection of new and more effective oximes.

The inability of standard therapy to provide adequate protection against poisoning by organophosphorus compounds (pesticides and nerve agents) motivated us to search for new, more effective oximes. We investigated the pharmacotoxicological properties of six experimental K-oximes (K027, K033, K048, K074, K075, and K203) in vivo. The therapeutic efficacy of K-oximes (at doses of 5 or 25 % of their LD50) combined with atropine was assessed in paraoxon-poisoned mice and compared with conventionally used oximes HI-6 and TMB-4. The bisoxime K074 was the most toxic (LD50=21.4 mg kg-1) to mice, while monoxime K027 was the least toxic (LD50=672.8 mg kg-1). With the exception of K033, all of the tested K-oximes showed better therapeutic efficiency than HI-6 and TMB-4. K027 and K048 stood out by demonstrating low acute toxicities and ensuring protective indices ranging from 60.0 to 100.0 LD50of paraoxon. Taking into account that these two oximes showed a similar therapeutic efficacy regardless of the applied doses, our results suggest that K027 and K048 could be antidotes for paraoxon intoxication.

4-5% of neonates are affected by rare diseases, 75% of which occur in children under ten years of age. This fact requires additional costs and special access. The aim of this paper is to analyze expenditures, policy and rare disease health care legislation (children comprise most of the patients). The survey focuses on the EU countries in comparison to the situation in the Czech Republic. The basic methods used are literature review, the analysis of available statistics data regarding the number of persons and related financial requirements for the treatment of rare diseases. The time series and histograms are generated.

We have applied a theoretical methodology, previously developed to evaluate the association and kinetic reactivation constants of oximes, comparing theoretical data obtained for human acetylcholinesterase (HsAChE) with in vitroresults from Mus musculusAChE (MmAChE) previously reported in the literature. Our results, further checked by additional molecular dynamics simulations steps, showed a good correlation between the theoretical and experimental data, supporting the methodology as appropriate for prediction of thermodynamic and kinetic parameters and corroborated MmAChE as a suitable model for studies with HsAChE.

AbstractExistence of alternative entrances in acetylcholinesterase (AChE) could explain the contrast between the very high AChE catalytic efficiency and the narrow and long access path to the active site revealed by X-ray crystallography. Alternative entrances could facilitate diffusion of the reaction products or at least water and ions from the active site. Previous molecular dynamics simulations identified side door and back door as the most probable alternative entrances. The simulations of non-inhibited AChE suggested that the back door opening events occur only rarely (0.8% of the time in the 10nstrajectory). Here we present a molecular dynamics simulation of non-inhibited AChE, where the back door opening appears much more often (14% of the time in the 12nstrajectory) and where the side door opening was observed quite frequently (78% of trajectory time). We also present molecular dynamics, where the back door does not open at all, or where large conformational changes of the AChE omega loop occur together with alternative passage opening events. All these differences in AChE dynamical behavior are caused by different protonation states of two glutamate residues located on bottom of the active site gorge (Glu202 and G450 in Mus MusculusAChE). Our results confirm the results of previous molecular dynamics simulations, expand the view and suggest the probable reasons for the overall conformational behavior of AChE omega loop.

Electrochemical biosensor based on electric eel acetylcholinesterase (AChE) (EC 3.1.1.7) was performed for assay of nerve agents – tabun, sarin, soman, cyclosarin, and VX. The biosensor used AChE as biorecognition element. The presence of nerve agents was accompanied by a strong inhibition of AChE activity. Enzyme activity is easily measurable by electrochemical oxidation of thiocholine created from acetylthiocholine (ATChCl) by AChE‐catalyzed hydrolysis. The tested nerve agents were successfully assayed. The best limits of detection were achieved for sarin (5.88×10−10M) and VX (8.51×10−10M) after one‐minute assay. The biosensor was found long term stable at low as well as laboratory temperature.

We studied bispyridinium oxime K203 [(E)-1-(4-carbamoylpyridinium)-4-(4-hydroxyiminomethylpyridinium)-but-2-ene dibromide] with tabun-inhibited human acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) in vitro, and its antidotal effect on tabun-poisoned mice and rats in vivo. We compared it with oximes K048 and TMB-4, which have proven the most efficient oxime antidotes in tabun poisoning by now. Tabun-inhibited AChE was completely reactivated by K203, with the overall reactivation rate constant of 1806 L mol-1min-1. This means that K203 is a very potent reactivator of tabun-inhibited AChE. In addition, K203 reversibly inhibited AChE (Ki= 0.090 mmol L-1) and BChE (Ki= 0.91 mmol L-1), and exhibited its protective effect against phosphorylation of AChE by tabun in vitro. In vivo, a quarter of the LD50K203 dose insured survival of all mice after the application of as many as 8 LD50doses of tabun, which is the highest dosage obtained compared to K048 and TMB-4. Moreover, K203 showed high therapeutic potency in tabun-poisoned rats, preserving cholinesterase activity in rat plasma up to 60 min after poisoning. This therapeutic improvement obtained by K203 in tabun-poisoning places this oxime in the spotlight for further development.

The present approaches to the development of prophylactic and therapeutic antidotes against nerve agentsNerve agents belong to highly toxic organophosphorus compounds misused as chemical warfare agents for military as well as terroristic purposes. Basic mechanism of action of nerve agents is based on acetylcholinesterase (AChE, EC 3.1.1.7) inhibition and subsequent accumulation of neuromediator acetylcholine at the cholinergic synapses, either peripheral or central leading to cholinergic hyperstimulation and development of symptoms of poisoning, followed by metabolic dysbalance and death without effective prophylaxis/treatment. The antidotal treatment of acute poisonings with nerve agents still represents a serious problem and, therefore, we are searching how to satisfactorily protect people against acute toxicity of nerve agents. There are two approaches how to improve the medical protection against nerve agents:to increase the resistance of nerve agent-exposed organism and the efficacy of post-exposure antidotal treatment by pharmacological prophylaxisthe development of new, more effective antidotes, expecially AChE reactivators, to achieve the satisfactorily effective antidotal treatment of acute poisonings with nerve agents.

Eleven Amaryllidaceae alkaloids (1–11)were isolated from fresh bulbs of Chlidanthus fragransHerb. The chemical structures were elucidated by MS, and 1D and 2D NMR spectroscopic experiments. Complete NMR assignments were achieved for deoxypretazzetine (1). All compounds were evaluated for their erythrocytic acetylcholinesterase and serum butyrylcholinesterase inhibition activity using Ellman's method. In the prolyl oligopeptidase assay, Z-Gly-Pro-p-nitroanilide was used as substrate. In biological assays, only the crinine type Amaryllidaceae alkaloid undulatine showed promising acetylcholinesterase and prolyl oligopeptidase inhibition activity with IC50values of 23.0 ± 1.0 μM and 1.96 ± 0.12 mM, respectively. Other isolated compounds were considered inactive.