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Journal Article 2009; 30(Suppl 1): 192-198 PubMed PMID: 20027170 Citation  Keywords:  Aluminum Hydroxide:administration & dosage, Animals, Anti-Bacterial Agents:toxicity, Carps:embryology, Dose-Response Relationship, Drug, Polymers:administration & dosage,.   

OBJECTIVES: The aim of this study is to assess the toxicity of PAX-18 in different developmental stages of common carp (Cyprinus carpio). The preparation PAX-18, with its active ingredient polyaluminium chloride (9% of Al), is a coagulation agent that is used mainly to precipitate phosphates, to prevent surface water eutrophication and incidences of cyanobacteria. It is applied to the water environment and thus could present a potential risk to fish.

DESIGN: The toxicity tests were performed on common carp according to OECD (203, 210) methodologies. The acute toxic effect was evaluated for juveniles and the early development stage effect was observed in embryo-larval toxicity tests. The results of the toxicity tests (the number of dead individuals at particular test concentrations) were subjected to a probit analysis using an EKO-TOX 5.2 programme to determine the LC50 values of PAX-18.

RESULTS: Acute toxicity value expressed as 96hLC50 was 753.1 +/- 24.3 mg.l-1 (67.8 mg.l-1 Al). Effect on early development stage expressed as the no observed effect concentration was 10 mg.l-1 (0.9 mg.l-1 Al), the lowest observed effect concentration was 50 mg.l-1 (4.5 mg.l-1 Al). No significant effects of the preparation PAX-18 in concentrations of 50 mg.l-1 of PAX-18 and lower were found on hatching, length and weight parameters, morphology and histopathology.

CONCLUSION: The lethal concentration of PAX-18 found in acute toxicity tests on common carp was 7-14 times higher than the concentration which is usually applied to water (5-10 mg.l-1 Al). Moreover, fish in eutrophicated water sources are exposed to PAX-18 concentrations corresponding with the lowest observed effect concentration only for a short time, therefore the effect on them can be considered as minimal....

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Comparative Study 2009; 30(Suppl 1): 186-191 PubMed PMID: 20027169 Citation  Keywords:  Animals, Antioxidants:metabolism, Arvicolinae, Disease Susceptibility, Mice, Mice, Inbred BALB C, Molecular Weight, Tularemia:metabolism,.   

OBJECTIVES: Bacterium Francisella tularensis is the causative agent of tularemia disease. It is a zoonosis accompanied with high mortality when untreated. Small rodents and hares, in particular, are natural reservoirs of tularemia. Despite physiological similarity of common hosts, tularemia exerts different mortality rates. The pathogenesis of tularemia is still not fully understood. The main pathway is associated with proliferation in macrophages after activation by reactive oxygen species in phagosomes.

DESIGN: A fully virulent strain of F. tularensis subsb. holarctica was used for infection of laboratory BALB/c mice (Mus musculus) and common voles (Microtus arvalis) representing murine and microtine species. The total level of low-molecular- weight antioxidants (LMWA) in plasma was assayed by cyclic voltammetry.

RESULTS: It was found that common voles are more resistant to tularemia progression when compared to mice. When LMWA assayed, surprising changes in LMWA levels were found. Both mice and common voles were infected with high dose resulting in overall mortality. While there was a quick depletion of LMWA in plasma in mice, common voles were even able to increase LMWA.

CONCLUSION: It seems that LMWA play an important role in the organism s protection during tularemia. The ability to compensate the LMWA losses and increase levels of antioxidants in common voles is probably responsible for its lower susceptibility to tularemia....

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Journal Article 2009; 30(Suppl 1): 182-185 PubMed PMID: 20027168 Citation  Keywords:  Age of Onset, Aged, Carcinogens, Environmental:toxicity, Case-Control Studies, Chromium:toxicity, Humans, Lung Neoplasms:epidemiology, Male, Middle Aged, Occupational Exposure, Small Cell Lung Carcinoma:epidemiology, Time Factors,.   

OBJECTIVE: Workers chronically exposed to hexavalent chromium have higher incidence of lung cancer. Our study investigates incidence of lung cancer types, age at onset of the disease and survival time among chromium exposed workers (smelters, tapers, crane operators) in comparison to non-exposed persons.

METHODS: 64 chromium exposed workers and 104 male controls with diagnosed lung cancer were analysed. The average exposure time among workers was 16.71 +/- 10.02 (S.D.) years (range 1- 41 years).

RESULTS: Chromium exposure significantly decreases the age at the onset of the disease by 3.51 years (62.20 +/- 9.08 years in exposed group and 65.71 +/- 10.50 years in control; P=0.018). Small cell lung carcinoma (SCLC) forms 25.0 % of all cases in chromium exposed workers and 16.34% in non exposed individuals. No correlation was found between the age at the diseases onset and time of exposure. The mean survival time in exposed group was 9.03 +/- 12.73 month, in control 12.14 +/- 21.94 month, but this difference was not significant (P=0.473).

CONCLUSION: Occupational exposure to chromium was identified as an important risk factor of lung cancer, decreasing the age at the diseases onset. Higher percentage of SCLC was found in chromium exposed individuals....

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Journal Article 2009; 30(Suppl 1): 177-181 PubMed PMID: 20027167 Citation  Keywords:  Adolescent, Adult, Aged, Aging, Animals, Child, Child, Preschool, Dental Amalgam, Diet, Environmental Exposure:analysis, Female, Fishes, Hair:chemistry, Humans, Male, Mercury:analysis, Middle Aged, Sex Characteristics, Young Adult,.   

OBJECTIVES: Exposure to mercury, a risk factor for neuro-developmental toxicity, was evaluated in the Czech Republic by performing mercury determination using human hair as an indicator.

METHODS: Hair samples from Czechs (n=311; 2-66 years old) were analyzed for mercury content. Total mercury was analysed by mercury analyzer AMA 254.

RESULTS: The highest total mercury content found in sampled hair was 3.55 microg/g and the lowest content was 0.015 microg/g. No correlation was found between the mercury levels in the sampled hair and the subject's age, gender, and the amount of amalgam fillings. A total of 38 hair samples were analyzed for methylmercury content.

CONCLUSION: The results show a positive correlation between the total mercury content in human hair and the consumption of marine and freshwater fish. Hair are a very good indicator of fish consumption....

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Journal Article 2009; 30(Suppl 1): 169-176 PubMed PMID: 20027166 Citation  Keywords:  Animals, Biomarkers:analysis, Cadmium:analysis, Cyprinidae:metabolism, Cysteine:metabolism, Czech Republic, Glutathione:metabolism, Liver:chemistry, Metals:analysis, Rivers:chemistry, Spectrophotometry, Atomic, Sulfhydryl Compounds:analysis,.   

OBJECTIVES: The aim of this study was to assess the effect of metals, with special attention of cadmium (Cd), content of the Svitava and Svratka rivers (Czech Republic) on levels of thiol compounds such as metallothioneins (MT), glutathione (GSH/GSSG), and cysteine (Cys) concentrations in chub (Leuciscus cephalus L.) liver and their use as biomarkers.

DESIGN: Levels of thiol compounds in fish liver were determined by the differential pulse voltammetry Brdicka reaction. Cadmium content in L. cephalus liver was measured by atomic absorption spectometry (AAS) with electrothermal atomization. The contents of thiols and Cd were correlated with the Cd and metals content of river bottom sediments.

RESULTS: Results were inconsistent with those of experimental studies. Correlations between liver Cd content and MT, Cys, GSSG were not significant in any locality (p > 0.05). Cd liver content was negatively (p< 0.05) correlated with GSH at one (Zidlochovice) of the seven tested sites. GSH and GSSG correlated negatively in five localities (p > 0.05). Correlations between Cd in sediment and Cys and GSSG (p > 0.05), and MT was negative (p< 0.05). The relationship between sum of metals value and MT was negative (p< 0.05), similarly with GSSG (p > 0.05).

CONCLUSION: Many factors influence content of MT, GSH, and GSSG, and data for Cd were equivocal. Monitoring the aquatic ecosystem to identify metal content using thiol compounds in fish liver as biomarkers is complex. More relevant data including laboratory experiments will be required to assess most of the factors influencing thiols and their relevance to Cd contamination....

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Journal Article 2009; 30(Suppl 1): 163-168 PubMed PMID: 20027165 Citation  Keywords:  Animals, Blood Chemical Analysis, Brain:metabolism, Diet, Dietary Supplements, Food, Food Microbiology, Fungi, Male, Metallothionein:metabolism, Mycotoxins:administration & dosage, Rats, Rats, Wistar, Spectrum Analysis, Triticum:microbiology, Vitamins:adm.   

OBJECTIVE: The aim of this study is to determine level of metallothioneins (MTs) in brain tissues of rats administered by feed mixtures with different content of mouldy wheat or fungi.

DESIGN: Selected male laboratory rats of Wistar albino at age of 28 days were used in our experiments. The rats were administered by feed mixtures with different content of vitamins, naturally mouldy wheat or fungi for 28 days. At the very end of the experiment, the animals were put to death and brains were sampled. MT level was determined by differential pulse voltammetry Brdicka reaction.

RESULTS: We found that MTs' level in brain tissues from rats administered by standard feed mixtures was significantly higher compared to the level of MTs in rats supplemented by vitamins. Further we studied the effect of supplementation of naturally mouldy wheat on MTs level in rats. In mouldy wheat we detected the presence of following fungi species: Mucor spp., Absidia spp., Penicillium spp., Aspergillus spp. and Fusarium spp. Moreover we also identified and quantified following mycotoxins - deoxynivalenol, zearalenone, T2-toxin and aflatoxins. Level of MTs determined in rats treated with 33 or 66% of mouldy wheat was significantly lower compared to control ones. On the other hand rats treated with 100% of mouldy wheat had less MTs but not significantly. Supplementation of vitamins to rats fed by mouldy wheat had adverse effect on MTs level compared to rats with no other supplementation by vitamins. Moreover vitamins supplementation has no effect on MTs level in brain tissues of rats treated or non-treated with Ganoderma lucidum L.

CONCLUSION: Both mycotoxins and vitamins have considerable effect on level of MTs in brain tissues. It can be assumed that the administered substances markedly influence redox metabolism, which could negatively influence numerous biochemical pathways including those closely related with MTs....

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Journal Article 2009; 30(Suppl 1): 156-162 PubMed PMID: 20027164 Citation  Keywords:  Animals, Capsules, Chromatography, Gas, Cod Liver Oil:analysis, Dietary Supplements:analysis, Fish Oils:analysis, Food Contamination, Gadiformes, Gas Chromatography-Mass Spectrometry, Humans, Liver:chemistry, Mercury:analysis, Methylmercury Compounds:anal.   

OBJECTIVES: The aim of this study is to determine the content of mercury, methylmercury and persistent organic pollutants in the capsules filled with fish oil from marine fish and in the canned cod liver and find out, whether analyse products are safe and suitable for human consumption.

METHODS: Total mercury was determined by cold vapour atomic absorption spectroscopy on an AMA-254 (Altec Ltd., Czech Republic) single-purpose mercury analyzer. Methylmercury in the cod liver in the form of chlorid methylmercury was determined by gas chromatography. Seven indicator congeners of PCB (PCB 28, 52, 101, 118, 138, 153, 180), HCH, HCB, DDT and its degradation products DDE and DDD, were determined by gas chromatography-mass spectrometry.

RESULTS: In capsules filled with fish oil (n=19) total Hg levels were in the range of 0.013 to 2.03 ng/g. All the capsule oil samples analyzed for MeHg were below the detection limit. The highest concentration of total Hg was found in cod liver - can A (0.223 ng/g). The maximum percentage of MeHg in total Hg concentration was found in a liver sample - can B. The values of alpha-, beta-, gamma-, delta- HCH and of HCB were found below the detection limits in all the capsule samples analyzed. In eight capsules, the presence of highly lipophilic PCB congeners was demonstrated. DDT and its important DDE metabolite were found in ten samples. In canned cod liver the highest concentration of all PCB congeners was demonstrated in can D. The lowest congener concentrations, however, were found in smoked cod liver - can C. DDT with its main metabolite DDE was detected in can C. No additional DDT and DDD persistent pollutants were detected.

CONCLUSIONS: The consumption of fish oil in capsules, and canned cod liver is safe and healthy and should be encouraged....

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Journal Article 2009; 30(Suppl 1): 152-155 PubMed PMID: 20027163 Citation  Keywords:  Acetylcholinesterase:metabolism, Biosensing Techniques, Cholinesterase Inhibitors:chemistry, Cholinesterase Reactivators:chemistry, Enzymes, Immobilized:antagonists & inhibitors, Isomerism, Organophosphorus Compounds:chemistry, Oximes:chemistry, Pralidoxi.   

OBJECTIVES: Quantification of efficacy of monopyridinium isomers and homologs derived from clinically used Pralidoxime within reactivation of acetylcholinesterase inhibited with organophosphorus nerve agents.

METHODS: This work uses the colorimetric biosensor called Detehit - cotton cloth with immobilized enzyme acetylcholinesterase. Biosensor is based on the modificated Ellman's method.

RESULTS: The highest reactivation was observed with sarin-inhibited acetylcholinesterase. Substantially lower reactivation was found with the cyclosarin-inhibited enzyme whereas AChE, inhibited by soman could not be effectively reactivated under the given conditions (enzyme inhibition for 2 minutes and subsequent treatment with the reactivator for 15 minutes).

CONCLUSION: Our work gives comparison of efficacy of reactivators in dependence on the length of alkylene chain and position of aldoxime functional group. Evaluation of effectivity of aldoxime reactivators is provided by simple means. The method allows rapid in vitro evaluation of the reactivators without being disturbed by excess of the organophosphate or reactivator....

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