Jiri Lamka

Charles University in Prague, Praha, Praha, Czech Republic

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Publications (27)62.5 Total impact

  • Alena Lorencova · Jiri Lamka · Michal Slany
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    ABSTRACT: Toxoplasma gondii is the causative agent of the most common parasitic infection in humans. Almost all warm-blooded animals, as well as humans, can act as intermediate hosts that harbour infective cysts in their tissues. Felids act as definitive hosts excreting oocysts in faeces. In humans, T. gondii can cause subclinical infection but also severe clinical disease with a wide range of symptoms, especially in immunocompromised individuals. The infection is usually asymptomatic in animals and is not recognized at either ante- or post-mortem inspection. The consumption of undercooked meat from infected animals is one of the most important routes by which the infection can be transmitted to humans. Handling of the organs and other tissues of game animals and eating their undercooked meat have been described as a risk of T. gondii infection. For diagnosis of toxoplasmosis, the combination of serological and molecular methods has been described as a suitable approach. Antibodies against T. gondii were detected in 20.8%, 50.0%, 23.1%, and 24.4% of red deer, sika deer, fallow deer and mouflons, respectively, coming from game preserves and farms in the Czech Republic. T. gondii DNA was found in the muscle tissue of red deer (8.3%) and mouflons (14.6%). The lower prevalence rates based on molecular screening could be due to the random distribution and low density of cysts in tissues of infected animals. Bearing in mind the increase in the number of hunted animals and the growing trend in game consumption, it is important to educate hunters and game meat consumers about the risk of exposure to this zoonotic infection during handling and consumption of the meat.
    No preview · Article · Aug 2015 · Potravinarstvo
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    ABSTRACT: The aims of this study were to describe spatial contamination of the environment on a mouflon pasture, as well as to assess the contamination of grass and roots after surface contamination and in depth contamination with feces and buried tissues from animals infected with Mycobacterium avium subsp. paratuberculosis (M. a. paratuberculosis). Samples of soil, roots, and aerial parts of plants were collected from different locations inside the mouflon pasture, and one control sample site was chosen outside the area where the animals are living. M. a. paratuberculosis DNA was present in all the examined sites and was more often detected in roots than in soil. DNA was detected at up to 80 cm of depth and was spatially more widespread than the initial hypothesis of M. a. paratuberculosis leaching vertically into deeper layers of soil. This study broadens our knowledge of the spread and persistence of M. a. paratuberculosis in an environment with highly infected animals.
    No preview · Article · Jun 2014 · Current Microbiology
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    ABSTRACT: There is no European legislation concerning paratuberculosis that requires that imported animals be kept in quarantine and commonly they are directly released into areas with other animals. In this study, detection of latent infection of paratuberculosis in healthy mouflons previously diagnosed as paratuberculosis-free, but originating from a real time quantitative PCR- (qPCR-) positive herd, occurred after their transport to a new farm. During a twelve-day quarantine period, all mouflons irregularly shed Mycobacterium avium subsp. paratuberculosis (MAP) in faeces, and in a small number of cases also in milk. After the animals were released from quarantine, MAP was detected for a further two days, after which, testing was negative, except in one case. Therefore, the stress connected with transport, novel environment, dietary change, or limited area with high density of animals might have contributed to the induction of paratuberculosis and the shedding of MAP from the animals, previously diagnosed as MAP-negative. According to these results, the keeping of imported animals in quarantine and their examination for MAP presence not only before the transport but also afterwards should be recommended. The designation of a particular area of a farm as a quarantine enclosure could help to mitigate the impact of stress caused by a confined space with a high density of animals.
    Preview · Article · Mar 2014
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    ABSTRACT: Based on IS901 RFLP analysis of 36 Mycobacterium avium subsp. avium (MAA) isolates from 15 pheasants (Phasianus colchicus) and two goshawks (Accipiter gentilis) from four distinct pheasant farms, six different IS901 RFLP types (E, F, G, M, Q and V) were revealed. The distribution of IS901 RFLP profiles was tightly linked to individual flocks. Matching IS901 RFLP profiles found here indicate the likely transmission between pheasant and goshawks in the same locality. In two flocks, two distinct IS901 RFLP profiles were found in different pheasants within a flock, as well as in the various organs of five individual pheasants.
    Preview · Article · Feb 2013 · Journal of veterinary science (Suwŏn-si, Korea)
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    ABSTRACT: One isolate of Mycobacterium avium subsp. paratuberculosis was detected in 2,212 fecal samples of wild deer assembled in overwintering sites (OwS). Neither M. bovis nor M. a. subsp. avium was found. Therefore, congregating deer in OwSs does not automatically lead to the amplification of these pathogens among animals in OWSs.
    No preview · Article · Jul 2011 · Journal of wildlife diseases
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    ABSTRACT: The aim of this study was to demonstrate the persistence of Mycobacterium avium subsp. paratuberculosis (MAP) in soil and colonization of different plant parts after deliberate exposure to mouflon feces naturally contaminated with different amounts of MAP. Samples of aerial parts of plants, their roots, and the soil below the roots were collected after 15 weeks and examined using IS900 real-time quantitative PCR (qPCR) and cultivation. Although the presence of viable MAP cells was not demonstrated, almost all samples were found to be positive using qPCR. MAP IS900 was not only found in the upper green parts, but also in the roots and soil samples (from 1.00 × 10(0) to 6.43 × 10(3)). The level of soil and plant contamination was influenced mainly by moisture, clay content, and the depth from which the samples were collected, rather than by the initial concentration of MAP in the feces at the beginning of the experiment.
    No preview · Article · May 2011 · Current Microbiology
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    ABSTRACT: The aim of present project was to find out if in vivo contact of Haemonchus contortus with benzimidazole an-thelmintic flubendazole (FLU) during treatment of its hosts (sheep) with low doses of FLU affects helminths' drug-metabolizing enzyme activities. Four groups of lambs, experimentally infected with H. contortus, were treated three-times orally with 0.0, 0.25, 0.50 or 1.00 mg per kg of body weight of FLU in three consecutive days. Twenty four hours after the last FLU dose, the nematodes were isolated, homogenized and subcellular fractions were prepared. In these subcellular fractions, biotransformation of FLU and the activities of carbonyl reducing enzymes and conjugation enzymes were as-sayed. The results showed that H. contortus enzymes were able to conjugate p-nitrophenol with glucose but not with glu-curonic acid. The exposure of H.contortus to FLU (the highest FLU dose) caused a significant increase in activities of FLU reductases, D,L-glyceraldehyde reductases and glutathion S-transferases.
    Full-text · Article · Aug 2010 · The Open Parasitology Journal
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    ABSTRACT: The effect of flubendazole (FLU) therapy on in vitro FLU biotransformation and the activities of selected biotransformation enzymes were investigated in male and female lambs. Four experimental groups were used: control (untreated) ewes and rams and FLU-treated ewes and rams (orally, 15 mg/kg per day, for three consecutive days). Subcellular fractions were prepared from liver and intestinal mucosa 24 h after the final dosage was administered. Activities of cytochromes P450 (CYP), flavine monooxygenases (FMO), carbonyl reducing enzymes, UDP-glucuronosyl transferase (UGT) and glutathione S-transferase were tested. Significant gender differences were observed for FMO-mediated activity (2-fold higher in ram lambs) and UGT activity (up to 30% higher in ewe lambs), but no gender differences were observed in FLU metabolism. FLU-treatment of lambs moderately changed the activities of some CYPs, FMO, and UGT in liver microsomes. In vitro FLU reduction was not altered in the liver, but was slightly higher in the small intestine of FLU pre-treated lambs. This correlated with the higher carbonyl reductase activities measured in the gut mucosa of these animals.
    Preview · Article · Mar 2010 · Pharmacological reports: PR
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    ABSTRACT: With further use of chemical agents in the control of parasitic infections, an increased number of drug resistance occurrences to antiparasitic drugs has been reported. Induction of enzymes responsible for detoxification of given drugs can contribute to drug resistance development in a parasitic organism. The identification of formed metabolites allows the characterization of the enzymes participating in biotransformation and possibly in drug resistance development. The objective of our work was to find and identify phase I and phase II metabolites of the anthelminthic drugs albendazole, flubendazole and mebendazole formed in ex vivo incubations by the parasitic helminth Dicrocoelium dendriticum, a parasite of ruminants and other grazing animals, using liquid chromatography/mass spectrometric (LC/MS) techniques. In the ex vivo study, approximately 50 living D. dendriticum adults were incubated in 5 mL RPMI-1640 medium in the presence of 10.0 micromol L(-1) benzimidazole drug (5% CO(2), 38 degrees C) for 24 h. The bodies of the parasite were then removed from the medium. After homogenization of parasites, both parasite homogenates and medium from the incubation were separately extracted using solid-phase extraction. The extracts were analyzed using LC/MS with electrospray ionization. The results showed that D. dendriticum enzymatic systems are capable of phase I oxidation and reduction as well as phase II conjugation reactions. Detected phase I metabolites comprised albendazole sulfoxide, reduced flubendazole and reduced mebendazole. As for phase II metabolites, methyl derivatives of both reduced flubendazole and reduced mebendazole were observed.
    No preview · Article · Jul 2009 · Rapid Communications in Mass Spectrometry
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    ABSTRACT: Dicrocoeliosis, a helminthosis caused by lancet fluke (Dicrocoelium dendriticum), is at present considered a world-widely significant but little investigated parasitosis of farm, domestic and wild animals, and a relatively rare parasitosis of man. Lancet fluke particularly parasitizes in biliary duct, gallbladder and at the outlet of pancreas of its host, small ruminants. The only means so far generally accepted against fluke is pharmacotherapy and pharmacoprophylaxis practised in endangered or attacked breeds with the use of suitable anthelmintics (preference is given to benzimidazole anthelmintics). The aim of this project was to study the metabolism of benzimidazole anthelmintic albendazole ([5-(propylthio)-1H-benzimidazol-2-yl] methylcarbamate, ABZ) in lancet fluke subcellular fractions and to characterise the responsible enzymes. The results showed that ABZ is metabolised via sulphoxidation in lancet fluke in vitro. The highest velocity of ABZ sulphoxide (ABZSO) formation was found in mitochondria-like fraction, lower in microsomes-like fraction and none ABZSO arise in cytosole-like fraction. Several model inhibitors of biotransformation oxidation enzymes were used to characterise the enzymes responsible for sulphoxidation of ABZ. Salicylhydroxamic acid, mercaptosuccinic acid, octylamine, methimazole (MET) and alpha-naphthyl thiourea (ANTU) were used in incubations of ABZ with fluke's subcellular fractions. MET and ANTU, typical inhibitors of flavine monooxygenases (FMO) in mammals, significantly inhibited the ABZSO formation in lancet fluke. The concentration dependent inhibition was observed both in mitochondria-like and microsomes-like fractions. Values of IC50 were calculated. Based on inhibition study, FMO seemed to be responsible for ABZSO formation, although no activity of thiobenzamide-S-oxidase (typical reaction catalysed by FMO in mammals) was detected in lancet fluke. This contradiction indicate that lancet fluke's FMO does not use thiobenzamide as a substrate or MET and ANTU inhibit other oxidase than FMO. The results demonstrate considerable differences in biotransformation enzymes properties in mammals and helminths. This project was supported by Czech Science Foundation, grant No. 524/07/0611.
    No preview · Conference Paper · May 2009
  • Viktor Cvilink · Jiri Lamka · Lenka Skálová
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    ABSTRACT: Anthelminthics remain the only accessible means in the struggle against helminth parasites, which cause significant morbidity and mortality in man and farm animals. The treatment of helminthic infections has become problematic because of frequent drug resistance of helminth parasites. The development of drug resistance can be facilitated by the action of xenobiotic metabolizing enzymes (XMEs). In all organisms, XMEs serve as an efficient defense against the potential negative action of xenobiotics. The activities of XMEs determine both desired and undesired effects of drugs, and the knowledge of drug metabolism is necessary for safe, effective pharmacotherapy. While human and mammalian XMEs have been intensively studied for many years, XMEs of helminth parasites have undergone relatively little investigation, so far. However, many types of XMEs, including oxidases, reductases, hydrolases, transferases, and transporters, have been described in several helminth species. XMEs of helminth parasites may protect these organisms from the toxic effects of anthelminthics. In case of certain anthelminthics, metabolic deactivation was reported in helminth larvae and/or adults. Moreover, if a helminth is in the repeated contact with an anthelminthic, it defends itself against the chemical stress by the induction of biotransformation enzymes or transporters. This induction can represent an advantageous defense strategy of the parasites and may facilitate the drug-resistance development.
    No preview · Article · Feb 2009 · Drug Metabolism Reviews
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    ABSTRACT: Although benzimidazole anthelmintic flubendazole, methyl ester of [5-(4-fluorobenzoyl)-1H-benzimidazol-2-yl]carbamic acid, is extensively used in veterinary and human medicine for the treatment of gastrointestinal parasitic helminth infections, reliable data about its pharmacokinetics in various species have not been reported. Our previous work [M. Nobilis, Th. Jira, M. Lísa, M. Holcapek, B. Szotáková, J. Lamka, L.Skálová, J. Chromatogr. A 1149 (2007) 112-120] had described the stereospecificity of carbonyl reduction during phase I metabolic experiments in vitro. For in vivo pharmacokinetic studies, further improvement and optimization of bioanalytical HPLC method in terms of sensitivity and selectivity was necessary. Hence, a modified chiral bioanalytical HPLC method involving both UV photodiode-array and fluorescence detection for the determination of flubendazole, both enantiomers of reduced flubendazole and hydrolyzed flubendazole in the extracts from plasma samples was tested and validated. Albendazole was used as an internal standard. Sample preparation process involved a pH-dependent extraction of the analytes from the blood plasma into tert-butylmethyl ether. Chromatographic separations were performed on a Chiralcel OD-R 250 mm x 4.6mm column with mobile phase methanol-1M NaClO(4) (75:25, v/v) at the flow rate 0.5 ml min(-1). In quantitation, selective UV absorption maxima of 290 nm (for reduced flubendazole), 295 nm (for albendazole), 310 nm (for flubendazole) and 330 nm (for hydrolyzed flubendazole) were used in the UV photodiode-array detection, and lambda(exc.)/lambda(emis.)=228 nm/310 nm (for reduced flubendazole) and lambda(exc.)/lambda(emis.)=236 nm/346 nm (for albendazole) were set on the fluorescence detector. The fluorescence detection was approximately 10-times more sensitive than the UV detection. Each HPLC run lasted 27 min. The validated chiral HPLC-PDA-FL method was employed in the pharmacokinetic studies of flubendazole in sheep. The stereospecificity of the enzymatic carbonyl reduction of flubendazole was also observed in vivo. (+)-Reduced flubendazole was found to be the principal metabolite in ovine blood plasma and only low concentrations of hydrolyzed flubendazole, the parent flubendazole and (-)-reduced flubendazole were detected in this biomatrix.
    No preview · Article · Jan 2009 · Journal of Chromatography B
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    Preview · Article · Mar 2008 · The Open Veterinary Science Journal
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    ABSTRACT: Flubendazole (FLU) is a widely administered benzimidazole anthelmintic indicated for the control of parasitic diseases in farm animals including pigs and pheasants. This study was designed to test the biotransformation of FLU in control animals and animals treated with FLU in recommended therapeutic doses. The activities of several pheasant and porcine hepatic and intestinal carbonyl reducing enzymes and their modulation by FLU were also studied. Twelve adult pheasant hens, approximately 1 year old, were divided into two groups and treated for 7 days with placebo or 6 mg of FLU/kg of body weight. Eight male hog weaners, approximately 3 month old, were divided into two groups and treated for 5 days with placebo or 1.57 mg of FLU/kg of body weight. Subcellular fractions, prepared from livers and small intestines of control and FLU treated animals, were incubated with FLU. In vitro formation of two main FLU metabolites, reduced FLU, and hydrolyzed FLU were analyzed using HPLC. While FLU was reduced significantly more intensively in FLU-treated pheasants than in control animals, no differences were observed in pigs. These results were confirmed by measuring the enzyme activities: carbonyl reducing enzyme activities were increased in pheasants treated by FLU, whereas FLU did not affect these enzymes in pigs.
    No preview · Article · Feb 2008
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    ABSTRACT: The aim of this study was to evaluate the age- and sex-differences in pharmacokinetic of anthelmintic drug flubendazole (FLU; methyl-[5-(4-fluorbenzoyl)-1H-benzimidazole-2-y1]-carbamate) in sheep. Three male and three female lambs (three-months-old) were used for the first pharmacokinetic study and five month later the same animals (as matured rams and ewes) were used for repetition of pharmacokinetic FLU study. During whole experiments, all animals were healthy, parasitologically negative, without any pharmacological treatment and bred under the same conditions. In both pharmacokinetic studies, single dose of FLU (30 mg per kg of body weight) in oral suspension were administered. Blood samples were taken before administration of FLU and than in 0.5, 1, 2, 4, 6, 8, 10, 12, 24, 36, 48, 60 and 72 hour intervals after FLU administration. Blood samples were centrifuged and plasma was frozen until the extraction and analysis. FLU and its metabolites were extracted into tert-butylmethyl ether and analysed by HPLC with albendazole as internal standard and mixture of methanol and sodium perchlorate (3:1) as mobile phase. The main detected metabolite was reduced flubendazole (FLU-R, compound with reduced keto group) and only traces of other metabolite (hydrolysed flubendazole) were found. Two enantiomers of FLU-R were detected on the chromatogram: (‑)‑enantiomer at retention time 14.2 min and (+)-enantiomer at 17.0 min. Considerable differences between lambs and mature sheep in plasmatic FLU-R concentrations were observed. In lambs, the Cmax value was achieved at 10 hours after FLU administration (300 pmol of (+)‑FLU-R and 14 pmol of (-)-FLU-R per ml of male plasma and 210 pmol of (+)-FLU-R and 7 pmol of (-)-FLU-R per ml of female plasma) while in mature animals Cmax value was achieved at 36 hours after FLU administration (590 pmol of (+)-FLU-R and 22 pmol of (-)-FLU-R per ml of male plasma and 440 pmol of (+)-FLU-R and 24 pmol of (-)-FLU-R per ml of female plasma). In mature sheep high concentration of both isomers of FLU-R remained in plasma up to 72 h after FLU administration of experiment. These findings document that lambs in comparison to mature animals absorb and metabolise FLU much faster but in lower range. This project was supported by Grant Agency of Czech Republic (Grant No 524/06/1345)
    No preview · Conference Paper · Jan 2008
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    ABSTRACT: Lancet fluke (Dicrocoelium dendriticum), being causal organism of dicrocoeliosis known in animals and man, continuously attract attention of scientific community. Only detailed knowledge of the properties of this parasite, including his defence mechanisms, can lead to successful control of parasitosis in mentioned hosts. The only means so far generally accepted against dicrocoeliosis is the use of suitable anthelmintics, especially benzimidazole ones. Biotransformation enzymes can, to a certain extent, protect the parasitic worms against the effects of xenobiotics including anthelmintics. The present study was designed to evaluate drug metabolizing enzymes activities in lancet fluke subcellular fractions. Activities of oxidation enzymes, carbonyl-reducing enzymes and conjugation enzymes were tested in subcellular fractions of D. dendriticum homogenate. Several enzyme activities corresponding to main isoforms of cytochrome P450 were measured in microsomes-like fraction but no activity was detected. On the other hand, activity of catalase (using europium (III)–tetracycline–hydrogen peroxide system) and peroxidase (assayed by measuring the H2O2 dependent oxidation of o-phenylendiamine) was proven in subcellular fractions. From conjugation enzyme activities, UDP-glucuronosyl transferase activity towards p‑nitrophenol in microsomes-like fraction and glutathione-S-transferase (GST) activity towards 1‑chloro-2,4-dinitrobenzene in cytosol-like fraction were assayed. The apparent kinetic parameters for GST reaction were determined: V´max = 1.64±0.25µM.min-1, K´m = 2.57±0.38 mM. Activities of carbonyl-reducing enzymes were tested using metyrapone, acenaphthenol, daunorubicin, and oracin. The results proved the ability of D. dendriticum enzymes to reduce the carbonyl group of xenobiotics. In lancet fluke, many model substrates were metabolized and the specific activities of some biotransformation enzymes were similar to the activities found in mammal host organisms. These results document the ability of D. dendriticum to effectively metabolize different xenobiotics and by this way be protected against the toxic effect of xenobiotics. This project was supported by the Grant Agency of Czech Republic, Grant No. 524/07/0611.
    No preview · Conference Paper · Jan 2008
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    ABSTRACT: Benzimidazole anthelmintics are widely used in veterinary medicine for prophylaxis and treatment of different endoparasitic diseases. Flubendazole, methyl ester of [5-(4-fluorobenzoyl)-1H-benzimidazol-2-yl]carbamic acid, has been mainly indicated for antiparasitic control in pig and poultry breeds. Before potential use of this drug in ruminant species, more informations about its biotransformation are necessary. A bioanalytical HPLC method was developed, validated and employed for flubendazole in vitro biotransformation studies in domestic sheep (Ovis aries) and wild sheep - mouflon (Ovis musimon). Microsomal and cytosolic subcellular fractions were prepared from liver of adult young rams (castrated or non-castrated) and adult mouflons (males or females). Flubendazole (in various concentrations) was incubated with NADPH and ovine microsomes or cytosol under aerobic conditions. The sample preparation step prior HPLC analyses involves pH-dependent liquid-liquid extraction of flubendazole and its phase I metabolites into ethyl acetate. Chromatographic analyses were performed on a LiChroCART 250 x 4 mm column containing LiChrospher 60 RPselectB, 5m (Merck, Darmstadt, Germany) with a precolumn (4 x 4 mm). A mixture of acetonitrile 0.025M phosphate buffer pH=3 (3:7, v/v) served as an isocratic mobile phase. The column effluent was monitored using a photodiode-array detector (scan or single wavelength at  = 246 nm). The whole analysis lasted 22 min at a flow rate of 1 ml.min-1. Two phase I flubendazole metabolites were found in the extracts: desmethylcarboxy flubendazole (tR = 5.2 min) and flubendazole with reduced carbonyl group (tR = 6.0 min). The chemical structures of these metabolites were confirmed using pure standards. With the aim to study the sex-differences in flubendazole biotransformation, the data obtained in castrated vs. noncastrated rams and male vs. female mouflons were compared. Comparing the data obtained in sheep and mouflon the differences in flubendazole biotransformation between domestic and wild ruminants were evaluated. The project was supported by Grant Agency of Czech Republic, Grant No 524/06/1345
    No preview · Conference Paper · Jan 2006
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    ABSTRACT: Flubendazole, methyl ester of [5-(4-fluorobenzoyl)-1H-benzimidazol-2-yl]carbamic acid, belongs to the group of benzimidazole anthelmintics, which are widely used in veterinary medicine. The phase I flubendazole biotransformation includes the hydrolysis of the carbamoyl methyl moiety accompanied by a decarboxylation (desmethylcarboxy-flubendazole) and a carbonyl reduction of flubendazole (reduced flubendazole). Flubendazole is a prochiral drug, hence two enantiomers of reduced flubendazole are formed during non-specific carbonyl reduction. For the metabolic studies, a chiral HPLC method enabling the separation of desmethylcarboxyflubendazole, both enantiomers of reduced flubendazole and parent flubendazole was developed. The sample preparation step involves pH-dependent liquid-liquid extraction of flubendazole and its phase I metabolites into t-butylmethyl ether. Chromatographic analyses were performed on a Chiralcel OD-R 250 x 4.6 mm column (Daicel Chemical Industries, Ltd). A mixture of acetonitrile 1 M aqueous NaClO4 (4 : 6, v/v) served as an isocratic mobile phase. The column effluent was monitored using a photodiode-array detector (scan or single wavelength at 300 nm). The whole analysis lasted 30 min at a flow rate of 0.5 ml/min. Extracts from liver and intestinal cytosole of pigs and pheasants after the incubation with flubendazole and coenzyme NADPH or NADH were analyzed. Enantioselectivity in the enzymatic carbonyl reduction of flubendazole was observed. While synthetic racemic mixture of reduced flubendazole was separated to equimolar amounts of both enantiomers, only one enantiomer was detected in the extracts from all incubates. This work was supported by Grant Agency of Czech Republic (524/06/1345) and by Grant Agency of Charles University (108/2005/C).
    No preview · Conference Paper · Jan 2006
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    ABSTRACT: Activities of biotransformation enzymes represent the major factor which determines efficacy of pharmacotherapy and behavior of drugs in organism. Present knowledge of biotransformation enzymes and their modulation in avian farm species, including pheasants, is quite insufficient, in spite of frequent use of veterinary drugs in pheasant semidomestic breeds. Mebendazole represents benzimidazole anthelmintic which was for a long period indicated for antiparasitic treatment and prophylaxis of pheasant parasitic diseases. This benzimidazole was well effective especially against main species of pararasitic nematodes. Mebendazole is declared to be safe without adverse effects at therapeutic levels (www.emea.eu.int). Activities of pheasant hepatic and intestinal carbonyl reducing enzymes and their modulation by anthelmintic mebendazole were investigated. Biotransformation of mebendazole in subcellular fractions prepared from livers and small intestines of control and mebendazole treated birds was investigated as well. Twelve adult pheasant hens, approx. two years old, were randomly divided into two groups. Birds in the first group were treated 7 days with therapeutic dose of mebendazole (6 mg/kg). Pheasants of the second group representing controls were administered with a placebo. After the termination of experimental schedule, the whole livers and small intestines were removed; the gut content washed out. Intestinal mucosa and liver tissue were homogenized and subcellular fractions were isolated. Microsomes and cytosol were incubated with mebendazole in various concentrations and NADPH. After incubation, extracts were analyzed using an HPLC. Cytosolic reductases activities were determined using metyrapone, daunorubicin and acenaphthenol as model substrates. Activities of pheasant carbonyl reducing enzymes were slightly but significantly increased in animals treated by mebendazole both in liver and in small intestine. These results were confirmed by incubation of mebendazole with subcellular fractions. Differences of data obtained from the treated and the control birds were quantified using One-way ANOVA. Summed up, the repeated administration of mebendazole to pheasant caused only slight modulation of tested biotransformation enzymes. Mebendazole seems to be relatively safe for pheasant therapy from the view of an enzymatic modulation. This project was supported by Grant Agency of Charles University, Grant No 108/2005/C.
    No preview · Conference Paper · Jan 2006
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    ABSTRACT: Bovine tuberculosis in wild boars (Sus scrofa) was detected in Central Europe during 1983-2001 in Croatia, Hungary and Slovakia. Accordingly, the purpose of the present study was investigation of mycobacterial infections in our country during 2002-2004 in a total of 2319 samples originating from 766 wild boars of different age categories from 29 (39.2%) of 74 districts of the Czech Republic. Individually collected anonymous faecal samples from 309 animals and 1 947 samples of various tissues from 457 animals were examined. Wild boars originated from both free nature (239 animals), and game parks (527 animals). Fifty boars and sows and 388 piglets and yearlings at the age of 1 to 2 years were included among 438 (57.1%) animals with known age and sex. Small tuberculous lesions in the intestinal lymph nodes were detected in 2 (0.3%) wild boars only. Causative agents of tuberculosis or paratuberculosis were not isolated from any of the animals. Mycobacteria were isolated from 64 (8.3%) wild boars. Mycobacterium avium subsp. avium, the causative agent of avian tuberculosis was isolated from intestinal lymph nodes of 7 (0.9%) wild boars (tuberculous lesions were detected in two animals). Thirty four infected wild boars originated from free nature and from a game park with occurrence of avian tuberculosis in domestic fowl, respectively. Atypical mycobacteria of 8 species (M. fortuitum, M. chelonae, M. scrofulaceum, M. triviale, M. terrae, M. phlei, M. smegmatis, and M. flavescens ) were isolated from 57 (7.4%) animals. Atypical mycobacteria were isolated from pulmonary lymph nodes, small and large intestines, intestinal mucosa and faeces of wild boars both from free nature and game parks. Due to the high density of wild boars and their large migration radius, they can be viewed as a potential source of a number of infections including the causative agent of avian tuberculosis.
    Full-text · Article · Jan 2006 · Veterinarski Arhiv

Publication Stats

138 Citations
62.50 Total Impact Points

Institutions

  • 2003-2015
    • Charles University in Prague
      • Faculty of Pharmacy in Hradec Králové
      Praha, Praha, Czech Republic
  • 2006
    • Veterinary Research Institute, Brno
      • Food and Feed Safety
      Brünn, South Moravian, Czech Republic
  • 2000-2006
    • University of Hradec Králové
      • Department of Chemistry
      Königgrätz, Královéhradecký, Czech Republic