Impact of cold exposure on life satisfaction and physical composition of soldiers.

This article has been retracted.

UHPLC-HRMS study of pharmacokinetics of a novel hybrid cholinesterase inhibitor K1234: A comparison between in silico, in vitro and in vivo data.

Alzheimer's disease (AD) is one of the most common forms of dementia. Current anti-AD therapeutics exploit the cholinergic hypothesis of its pathophysiology; they aim to inhibit cerebral cholinesterases. K1234 is a novel hybrid molecule derived from Huperzine A and 7-MEOTA-huperzine which shows increased potency in acetylcholinesterase inhibition in vitro compared to the compounds themselves. The study focused on description of the pharmacokinetic behaviour of K1234, blood-brain barrier penetration, identification of the main in vitro and in vivo metabolites. K1234 is relatively non-toxic compound, that is rapidly absorbed after i.p. administration reaching Cmax within minutes, with extensive distribution into tissues and fast metabolism in mice. The dominant metabolic pathway appears to be glucuronidation of the parent molecule and its phase-I metabolites. The passage of K1234 across the blood-brain-barrier in mice appears to be limited, as it reached only approximately one third of the AUC of plasma.

Peracetic acid-based disinfectant is the most appropriate solution for a biological decontamination procedure of responders and healthcare workers in the field environment.

AIMS: An effective decontamination procedure of personnel wearing personal protective equipment is required by CBRN responders and healthcare workers when dealing with biological warfare agents or natural outbreaks caused by highly contagious pathogens. This study aimed to identify critical factors affecting the efficacy of peracetic acid (PAA)-based disinfectants and products containing either hydrogen peroxide or sodium hypochlorite under the same conditions. METHODS AND RESULTS: The influence of concentration, application (contact) time, erroneous human behaviour, interfering substance, technical assets and weather conditions on disinfection efficacy against Bacillus subtilis spores were assessed in 14 experimental groups. Residual contamination of protective suits was measured to provide responders with readily understandable information (up to 100 colony forming units classified a suit as disinfected). Weather conditions, short application time and erroneous human behaviour substantially affected the effectiveness of PAAs (P < 0·05). Non-PAA-based disinfectants (either liquid or foam) did not reach comparable efficacy (P < 0·001). CONCLUSIONS: Peracetic acid was effective at a concentration of 6400-8200 ppm and an application time of 4 min. SIGNIFICANCE AND IMPACT OF THE STUDY: The study provides operationally relevant data for the use of PAA-based disinfectants in preparedness planning and management of biological incidents and natural outbreaks.

Tularemia - zoonosis carrying a potential risk of bioterrorism.

Tularemia, otherwise known as “rabbit fever”, is a zoonotic disease caused by a gram-negative intracellular bacterium - Francisella tularensis. The species is considered as a potential bioterrorism agent due to its high infectivity, the fact of being relatively easy to culture, the absence of human vaccine, and the potential for spreading through aerosol. In the Czech Republic, infection is usually caused by a tick bite, less frequently by a mosquito bite, direct contact with infected animals, or ingestion of contaminated water. The aim of this review is to provide a comprehensive view of tularemia, its diagnosis, clinical symptoms and treatment, along with the military perspective on a potential risk of F. tularensis to be misused as a biological weapon.

Decontamination of CBRN units contaminated by highly contagious biological agents.

A decontamination process plays a key role in management of biological incidents. While decontamination of surfaces and buildings located in the hot zone can be usually postponed until an agent is confirmed and an adequate planning phase is established, personnel wearing personal protective equipment must be decontaminated prior to their final exit from the hot zone. Because CBRN units require the shortest possible duration of this procedure, many factors must be considered, including concentration of biological agents, precleaning, disinfectant formulae, its concentration and spectrum of efficacy, contact time, external conditions (temperature, pH, relative humidity, soil load), technical assets used for decontamination, decontaminated surface (compatibility, pores), and staff performance. Experimental tests with surrogates of biological agents are thus necessary to identify above-mentioned points. Once an optimal decontamination procedure is recognized, a field rehearsal must follow and the method using a surrogate must be implemented into a training process of CBRN units.

Oxidative stress induced by oxime reactivators of acetylcholinesterase in vitro.

In this study, we determined the effect of methoxime (MMB-4), asoxime (HI-6), obidoxime (LüH-6), trimedoxime (TMB-4), and pralidoxime (2-PAM) on redox homeostasis in vitro. Cultured human hepatoma cells (HepG2) were exposed to oximes at concentrations equivalent to their IC50 (assessed using MTT assay) and evaluated 1, 4 and 24 h after incubation. Additionally, intact, early and late apoptotic and necrotic cells were quantified by microcapillary flow cytometry. Intracellular levels of oxygen/nitrogen species were determined using two fluorescent probes (2',7'-dichlorodihydrofluorescein diacetate and dihydroethidium). Malondialdehyde and 3-nitrotyrosine were measured by LC-MS/MS. Non-protein thiols and non-protein disulfides were evaluated using HPLC-UV to reflect antioxidant capacity. Oxidative and nitrosative stress was induced by LüH-6, TMB-4 and MMB-4, whereas 2-PAM and HI-6 appeared as weak oxidative stressors with no activity towards nitrosative stress in HepG2 cells. Based on these results, bisquartenary oxime reactivators containing two functional oxime groups at the position 4 of pyridinium ring appear as more intense oxidative and nitrosative inducers. Activation of apoptosis and necrosis do not seem to correlate with generation of RONS. On the other hand, both processes rather reflect MDA concentrations, i.e. the damage of biomolecules.

[Laparoscopic versus open left pancreatectomy: surgical stress response comparison in the porcine model]. / Srovnání operacní záteze u laparoskopické a otevrené levostranné pankreatektomie v experimentu na velkém laboratorním zvíreti.

INTRODUCTION: Although several techniques of laparoscopic left pancreatectomy have already been developed through experiments on animals and human patients, there is still insufficient information about their pathophysiological mechanisms, especially the impact on surgical stress. METHOD: In a group of 10 pigs, open left pancreatectomy was performed, and the other group of 10 pigs underwent laparoscopic left pancreatectomy. Postoperative stress was compared by determining serum levels of leukocytes, interleukin 1, 6 and CRP from peripheral venous blood collection. The blood was collected prior to incision, 1 and 2 hours after incision, 24 hours after the beginning of the procedure, and on the 7th postoperative day. RESULTS: No statistically significant difference was found between open and laparoscopic left pancreatectomy in the measured values of leukocytes, IL-1 and 6 and CRP.Key words: laparoscopy - left pancreatectomy surgical stress response interleukin 1 interleukin 6.

Using Clinical Signs and Symptoms for Medical Management of Radiation Casualties - 2015 NATO Exercise.

The utility of early-phase (≤5 days) radiation-induced clinical signs and symptoms (e.g., vomiting, diarrhea, erythema and changes in blood cell counts) was examined for the prediction of later occurring acute radiation syndrome (ARS) severity and the development of medical management strategies. Medical treatment protocols for radiation accident victims (METREPOL) was used to grade ARS severities, which were assigned response categories (RCs). Data on individuals (n = 191) with mild (RC1, n = 45), moderate (RC2, n = 19), severe (RC3, n = 20) and fatal (RC4, n = 18) ARS, as well as nonexposed individuals (RC0, n = 89) were generated using either METREPOL (n = 167) or the system for evaluation and archiving of radiation accidents based on case histories (SEARCH) database (n = 24), the latter comprised of real-case descriptions. These data were converted into tables reflecting clinical signs and symptoms, and submitted to eight teams representing five participating countries. The teams were comprised of medical doctors, biologists and pharmacists with subject matter expertise. The tables comprised cumulated clinical data from day 1-3 and day 1-5 postirradiation. While it would have reflected a more realistic scenario to provide the data to the teams over the course of a 3- or 5-day period, the logistics of doing so proved too challenging. In addition, the team members participating in this exercise chose to receive the cumulated reports of day 1-3 and 1-5. The teams were tasked with predicting ARS incidence, ARS severity and the requirement for hospitalization for multiple cases, as well as providing the certainty of their diagnosis. Five of the teams also performed dose estimates. The teams did not employ harmonized methodologies, and the expertise among the members varied, as did the tools used and the means of analyzing the clinical data. The earliest report time was 3 h after the tables were sent to the team members. The majority of cases developing ARS (89.6% ± 3.3 SD) and requiring hospitalization (88.8% ± 4.6 SD) were correctly identified by all teams. Determination of ARS severity was particularly challenging for RC2-3, which was systematically overestimated. However, RC4 was correctly predicted at 94-100% by all teams. RC0 and RC1 ARS severities were more difficult to discriminate. When reported RCs (0-1 and 3-4) were merged, on average 89.6% (±3.3 SD) of all cases could be correctly classified. Comparisons on frequency distributions revealed no statistically significant differences among the following: 1. reported ARS from different teams (P > 0.2); 2. cases generated based on METREPOL or SEARCH (P > 0.5); or 3. results reported at day 3 and 5 postirradiation (P > 0.1). Dose estimates of all teams increased significantly along with ARS severity (P < 0.0001) as well as with dose estimates generated from dicentric chromosomal-aberration measurements available for SEARCH cases (P < 0.0001). In summary, early-phase radiation-induced clinical signs and symptoms proved to be useful for rapid and accurate assessment, with minor limitations, toward predicting life-threatening ARS severity and developing treatment management strategies.

Comparison of the Radiosensitizing Effect of ATR, ATM and DNA-PK Kinase Inhibitors on Cervical Carcinoma Cells.

Here, we compared the effects of inhibitors of three phosphatidylinositol-3-kinase-related kinases, ATM, ATR a DNA-PK, on radiosensitization of cervical carcinoma cells. We demonstrated that DNA-PK inhibitor NU7441 enhanced phosphorylation of Chk1 and Chk2 kinases 2 h after irradiation of HeLa cells at a dose of 8 Gy in contrast to ATM kinase inhibitor KU55933, which completely blocked the Chk2 kinase phosphorylation on threonine 68, and ATR kinase inhibitor VE-821, which blocked the Chk1 kinase phosphorylation on serine 345. Most HeLa cells were accumulated in G2 phase of the cell cycle 24 h after irradiation at a high dose of 15 Gy, which was even potentiated after adding the inhibitors NU7441 and KU55933. Compared to all other irradiated groups, inhibitor VE-821 increased the number of cells in S phase and reduced the number of cells in G2 phase 24 h after irradiation at the high dose of 15 Gy. HeLa cells entered the mitotic cycle with unrepaired DNA, which resulted in cell death and the radiosensitizing effect of VE-821. Short-term application of the inhibitors (2 h before and 30 min after the irradiation by the dose of 8 Gy) significantly decreased the colony-forming ability of HeLa cells. Using real-time monitoring of cell proliferation by the xCELLigence system we demonstrated that while the radiosensitizing effect of VE-821 (ATR inhibitor) is manifested early after the irradiation, the radiosensitizing effect of KU55933 (ATM inhibitor) and NU7441 (DNA-PK inhibitor) is only observed as late as 72 h after the irradiation.

In vivo study of radioprotective effect of NO-synthase inhibitors and acetyl-L-carnitine.

This study investigated the protective effect of two nitric oxide synthase inhibitors N(omega)-nitro-L-arginine methyl ester (L-NAME, 100 mg/kg i.p.) and aminoguanidine (AG, 400 mg/kg i.p.), and an antioxidant acetyl-L-carnitine (ALC, 250 mg/kg i.p., once daily for five days) against radiation-induced damage in Wistar rats. Blood samples were collected 6 h after whole-body irradiation with 8 Gy. Plasma concentrations of nitrite+nitrate (NO(x)) and malondialdehyde (MDA) were measured by high-performance liquid chromatography. A single injection of L-NAME one hour before exposure effectively prevented the radiation-induced elevation of plasma NO(x) and it reduced 2.6-fold the risk for death during the subsequent 30-day period. Pretreatment with ALC prevented the radiation-induced increase in plasma MDA and it had similar effect on mortality as L-NAME did. Presumably due to its short half-life, the partially iNOS-selective inhibitor and antioxidant AG given in a single dose before exposure did not attenuate MDA and NO(x) and it failed to significantly improve the 30-day survival. In conclusion, pretreatment with both the nonspecific NOS inhibitor L-NAME and the antioxidant ALC markedly reduce mortality to radiation sickness in rats. The radioprotective effect may be directly related to effective attenuation of the radiation-induced elevation of NO production by L-NAME and of oxidative stress by ALC.

Ascorbic acid: an old player with a broad impact on body physiology including oxidative stress suppression and immunomodulation: a review.

Ascorbic acid is a low molecular weight antioxidant well known as anti-scorbut acting vitamin C in humans, primates and guinea pigs. This review summarizes basic data about ascorbic acid in its physiological action point of view. It is divided into biochemistry of ascorbic acid synthesis, mechanism of antioxidant action and participation in anabolism, pharmacokinetics and excretion, exogenous ascorbic acid immunomodulatory effect and participation in infectious diseases, impact on irradiation and intoxication pathogenesis, and supplementary demands. The primary intention was to consider ascorbic acid not only as an antioxidant but also as a chemical compound affecting multiple pathways with a potential beneficial impact in many diseases and processes in human body.

Morphometric analysis of the porcine gastrointestinal tract in a 10-day high-dose indomethacin administration with or without probiotic bacteria Escherichia coli Nissle 1917.

BACKGROUND: Nonsteroidal anti-inflammatory drugs may cause severe injury to all parts of the gastrointestinal tract. It has been hypothesised that probiotic bacteria might reduce this adverse effect. The aim of this study was to perform a morphometric evaluation of the gastrointestinal tract in experimental pigs treated using a 10-day high-dose of indomethacin with or without Escherichia coli Nissle 1917 (EcN). METHODS: Twenty-four healthy mature pigs were included: Group A (controls; 6 animals), Group B (EcN; n = 6), Group C (indomethacin; n = 6) and Group D (EcN & indomethacin; n = 6). EcN (3.5 × 10(10) live bacteria/day for 14 days) and/or indomethacin (15 mg/kg/day for 10 days) were administered. Specimens of the stomach, small and large bowel were routinely processed for microscopic examination. The height of glandular mucosa, height and width of interfoveolar spaces and villi and basement size of epithelial cells were evaluated. RESULTS: Different effects of indomethacin and EcN on particular parts of the gastrointestinal tract were shown. The indomethacin and probiotics group demonstrated a significantly lower height of cryptal mucosa and colonocytes and widening of the basement size of colonocytes compared to controls (p = 0.004; p < 0.001; p = 0.025). The height of cryptal mucosa was significantly higher in the EcN group compared to controls (p = 0.001). CONCLUSIONS: Indomethacin alone induced marked adaptation of the gastric mucosa. EcN alone provided a significant favourable trophic effect on the colonic mucosa. However, indomethacin and probiotics administered together comprise the worst impact on all porcine stomach, small and large bowel.

Confocal laser endomicroscopy in experimental pigs. Methods of ex vivo imaging.

BACKGROUND: Confocal laser scanning endomicroscopy (CLSE) enables online in vivo cellular surface and subsurface imaging of normal and pathological tissue at high resolution and magnification. The aim of this study was to work out a method of ex vivo in vitro CLSE in experimental pigs and to compare CLSE images with those of "classic" histology. MATERIAL AND METHODS: Five mature female pigs entered the study. CLSE on an ex vivo in vitro basis was started 10 minutes after pharmacological euthanasia and carried out for 30 minutes. Fluorescein was administrated i.v. as a fluorescence substance. RESULTS: CLSE was successful in all tissue samples of all animals (the oesophagus, stomach, small intestine, large bowel). We have succeeded to obtain high quality images within the first 30 minutes that means 40 minutes after the euthanasia of experimental animals. CLSE images corresponded well with those of haematoxylin-eosin staining. CONCLUSIONS: CLSE on an ex vivo in vitro basis in experimental pigs is feasible.

Gamma-radiation-induced phosphorylation of p53 on serine 15 is dose-dependent in MOLT-4 leukaemia cells.

Molecular indicators of the absorbed dose of ionizing radiation are powerful tools in biodosimetry. The studies reported here were undertaken with the motivation to find such a marker among the mo lecules involved in ataxia-telangiectasia mutated kinase- dependent signalling induced by ionizing radiation (ATM-kinase, checkpoint kinase-2, protein p53, and oncoprotein Mdm2). In our previous work on T-lymphocyte leukaemia MOLT-4 cells we described the mentioned molecules of ATM-dependent pathway and none of them showed a pronounced dosedependent response. Here we employed Western blotting and ELISA assay to investigate the response of post-translationally modified p53 (particularly phosphorylated on serine 15) after gamma-irradiation. We have found the amount of phosphorylated p53 to be homogenously increased after irradiation by the doses of 0.5 to 7.5 Gy. The dose-dependent response was pronounced especially after the doses up to 3.0 Gy. The presented data indicate that p53 phosphorylated on serine 15 might be used as a potential biodosimetric marker.

Activation of mitogen activated protein kinase (MAPK) pathways after soman poisoning in rat cerebellar granule neurons.

The expression of activated p38 mitogen-activated protein kinase (MAPK) and activated MAPK transcription factors c-jun, c-myc and elk-1 were examined in rat cerebellum after soman poisoning to determine the pathogenetic mechanism of the non-specific long-term effects of nerve agents. Male Wistar rats were poisoned by intramuscular administration of soman at a dose 60 microg kg(-1) (70% LD(50)) and samples were taken 1, 7 and 14 days after poisoning, immunohistochemically stained and p-p38MAPK, p-c-jun, p-c-myc and p-elk-1 expressions were measured using image analysis. Control groups were administered with saline instead of soman. The expression of activated p38MAPK and c-myc increased 14 days after soman poisoning while c-jun and elk-1 expressions remained unchanged 1, 7 and 14 days after soman poisoning. Delayed activation of p38 MAPK and its targets might be involved in the pathogenetic mechanism of the long-term neurophysiological toxic effects of nerve agents.