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Journal Article 2015; 36(Suppl 1): 46-52 PubMed PMID: 26757127 Citation  Keywords:  Animals, Carcinogens:metabolism, Cytochrome P-450 Enzyme System:drug effects, Flavonols:pharmacology, Inhibitory Concentration 50, Intestine, Small:drug effects, Liver:drug effects, Male, RNA, Messenger:drug effects, Rats, Rats, Wistar, Real-Time Polymera.   

OBJECTIVES: Dihydromyricetin (DHM) is a flavonoid, which has been shown to antagonize effects of ethanol intoxication. As a potential pharmacological agent, its biological interactions with enzymes metabolizing foreign compounds should be tested. Thus, the aim of this study was to analyze the influence of DHM on the induction and metabolic activity of selected cytochromes P450 (CYPs).

METHODS: After flavonoid administration by oral gavage to stomach the CYP expression at protein and mRNA levels was determined in rat liver and small intestine. The effects of flavonoids on CYP1A1/2, CYP1A2 or CYP2B1/2 enzyme activities in microsomes were measured using marker activities of these enzymes. Flavonoid-mediated inhibition of recombinant CYP1A2 was also assayed with luciferin-ME substrate. The flavonoid interaction with aryl hydrocarbon receptor (AhR) was assayed by reporter luciferase activity in Hep2G cells.

RESULTS: The value of half maximal inhibitory concentration of DHM for CYP1A1/2, CYP1A2, and CYP2B1 were determined to be 4.1, 14.2, and 98.5 mmol.L(-1), respectively. With the exception of a weak induction of CYP2B1 and CYP1A2 in the middle part of small intestine and in the liver, respectively, DHM did not affect the CYP expression at protein levels. On the contrary, real-time PCR revealed elevated expression of CYP1A1 and CYP1A2 mRNA in proximal part of the small intestine while decreased in the middle part. In the study utilizing the HepG2 cells, DHM showed only an additive effect on the benzo[a]pyrene-mediated activation of Ah receptor.

CONCLUSIONS: Dihydromyricetin doesn't significantly interfere with metabolic activity of CYP1A1/2 and CYP2B1 enzymes....

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Journal Article 2015; 36(Suppl 1): 100-105 PubMed PMID: 26757126 Citation  Keywords:  Anti-Bacterial Agents:analysis, Chromatography, High Pressure Liquid, Czech Republic, Drug Residues, Rivers:chemistry, Solid Phase Extraction, Sulfamerazine:analysis, Sulfamethazine:analysis, Sulfamethoxazole:analysis, Sulfonamides:analysis, Water Polluta.   

OBJECTIVES: The aim of this study was to assess the contamination level of aquatic ecosystems of the Oslava and the Jihlava Rivers, and of the Nove Mlyny Water Reservoir, situated in the South Moravian Region (Czech Republic), by residues of selected veterinary pharmaceuticals. We isolated and determined 10 sulfonamide antibiotics in samples of surface water and bottom sediments using optimized analytical methods.

DESIGN: A representative number of sampling sites in the entire basin of selected waters were chosen. Samples were collected particularly near the larger cities in order to assess their possible impact to the aquatic ecosystems. Extraction, pre-concentration and purification of samples were performed using optimized methods of solid phase extraction and pressurized solvent extraction. Final identification and quantification were carried out by high-performance liquid chromatography coupled with diode array detector.

RESULTS: The concentration of sulfonamides in water samples were all under the limit of detection. Regarding sediment samples, sulfadimidine was found at most sampling sites; its highest values were recorded in the Jihlava River (up to 979.8 µg.kg(-1) dry matter). Other frequently detected sulfonamides were sulfamethoxazole and sulfamerazine. Most other sulfonamides were under the limit of detection or limit of quantification.

CONCLUSIONS: Monitoring of antibiotic residues in the environment, especially in the aquatic ecosystem, is a current topic due to the growing worldwide use in both human and veterinary medicine. According to obtained results, we document the pollution of selected rivers and water reservoir by particular sulfonamides which basically reflects their application in veterinary medicine....

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Journal Article 2015; 36(Suppl 1): 95-99 PubMed PMID: 26757125 Citation  Keywords:  Acetylthiocholine:analogs & derivatives, Carboxymethylcellulose Sodium:analysis, Cellulose:analysis, Cholinesterase Inhibitors:metabolism, Dithionitrobenzoic Acid, Lactose:analysis, Materials Testing, Porosity, Povidone:analysis, Sulfhydryl Reagents,.   

OBJECTIVES: The aim of the study was to use methods of pharmaceutical technology, and prepare carriers in the form of pellets suitable as a filling of detection tubes for enzymatic detection of cholinesterase inhibitors. The enzymatic detection was based on enzymatic hydrolysis of acetylthiocholine iodide and the subsequent colour reaction of its hydrolysis product with Ellman's reagent. The suitable carriers should be in the form of white, regular and sufficiently mechanically resistant particles of about 1 mm allowing it to capture the enzyme during the impregnation process and ensuring its high activity for enzymatic detection.

METHODS: Carriers consisting of microcrystalline cellulose, lactose, povidone, and sodium carboxymethyl cellulose were prepared using extrusion-spheronization method under three different drying conditions in either a hot air oven or a microwave oven. Subsequently, the carriers were impregnated with acetylcholinesterase and their size, shape, mechanical resistance, bulk, tapped and pycnometric density, Hausner ratio, intraparticular and total tapped porosity, and activity were measured and recorded.

RESULTS: In this procedure, carriers with different physical parameters and different acetylcholinesterase activity were evaluated. It was found that higher acetylcholinesterase activity was associated not only with a higher intraparticular porosity but also with more regular particles characterized by high sphericity and low total tapped porosity.

CONCLUSION: This unique finding is important for the preparation of detection tubes based on enzymatic detection which is still irreplaceable especially in the field of detection and analysis of super-toxic cholinesterase inhibitors....

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Journal Article 2015; 36(Suppl 1): 38-45 PubMed PMID: 26757124 Citation  Keywords:  Animals, Antibodies:immunology, Antibody Formation, Blotting, Western, Cell Line, Tumor, Chickens, Cytochrome P-450 Enzyme System:immunology, Cytochrome P450 Family 2, Eggs, Electrophoresis, Gel, Two-Dimensional, Enzyme-Linked Immunosorbent Assay, Humans,.   

OBJECTIVES: Cytochromes P450 (CYP) are monooxygenases, which metabolize mostly hydrophobic endogenous and exogenous compounds. CYPs without any clear connection to metabolism are called "orphans". Interestingly, these "orphan" CYPs are over-expressed in tumor tissues. Thus, the main aim of the paper is the development of antibodies for immunodetection of these CYPs as potential malignancy markers.

METHODS: Unique sequences of CYP2S1 and 2W1 were selected and peptides synthesized. Chickens were immunized with peptides bound to hemocyanin (KLH). The antibodies were isolated from egg yolks and their reactivity was tested by ELISA. Antibodies were further affinity purified on immobilized peptides. Western blots containing CYP2S1 and 2W1 standards were developed with purified antibodies.

RESULTS: Using unique peptide immunogens of CYP2S1 and 2W1 the antibodies were developed. As judged from ELISA all chickens produced specific antibodies against the respective peptides. Both affinity purified antibodies against CYP2S1 peptide recognized the CYP2S1 standard on Western blots, but only one of four anti-peptide antibodies against CYP2W1 reacted with CYP2W1 standard. The antibodies were used for the detection of CYPs in cancer cell lines and human tissues samples. Although both CYPs were frequently co-expressed in cancer cells, CYP2S1 was solely induced in the cell line BxPC3, while CYP2W1 was predominantly present in cell lines MCF7 and HeLa. Our data show that anti-peptide antibodies are an indispensable tool for detection of homologous CYPs.

CONCLUSIONS: The anti-peptide antibodies successfully recognized CYP2S1 and 2W1 in the cancer cell lines and tissue samples....

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Journal Article 2015; 36(Suppl 1): 73-78 PubMed PMID: 26757123 Citation  Keywords:  Animals, Anti-Inflammatory Agents, Non-Steroidal:pharmacology, Gills:drug effects, Glutathione Peroxidase:drug effects, Glutathione Transferase:drug effects, Kidney:drug effects, Lipid Peroxidation:drug effects, Liver:drug effects, Naproxen:pharmacology, .   

OBJECTIVES: The aim of this study was to investigate the effects of the nonsteroidal antiinflammatory drug naproxen on adult zebrafish (Danio rerio).

METHODS: Three months old zebrafish (Danio rerio) were exposed to naproxen at concentrations of 0.001, 0.1 and 5 mg.L(-1). We focused on the changes in oxidative stress indices during and at the end of the experiment and histopathological examination of tissues after a two week long exposure period.

RESULTS: We found that a 3 day long exposure to naproxen causes mild oxidative stress and affects detoxification in zebrafish, which is demonstrated by the increased activity of glutathione peroxidase and glutathione S-transferase at 0.001 and 0.1 mg.L(-1) of naproxen, respectively. After a 7 day long exposure to 0.1 and 5 mg.L(-1), more potent effects on enzymes occur. However, these effects are only short lasting. At the end of the experiment, the activities of the target enzymes recover back to homeostatic baseline levels. Except catalase, which is induced only after a two week long exposure to the environmental concentration of naproxen. Despite the fact that naproxen causes mild oxidative stress in zebrafish, exposure to this drug does not result in lipid peroxidation. Histopathological examination revealed obvious changes to the gills and liver even at exposure to the environmental concentration of naproxen.

CONCLUSION: This study demonstrates that the environmental concentration of naproxen can slightly influence both the antioxidant defense system and histopathology of non-target fish....

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Case Reports 2015; 36(Suppl 1): 53-56 PubMed PMID: 26757122 Citation  Keywords:  Asphyxia Neonatorum:complications, Disease Management, Humans, Infant, Newborn, Methadone:adverse effects, Morphine:therapeutic use, Narcotics:adverse effects, Neonatal Abstinence Syndrome:drug therapy, Opiate Substitution Treatment:adverse effects,.   

: The aim of this work is to present the pitfalls of management of newborns with neonatal withdrawal syndrome (NWS) of different forms, which were complicated with the presence of severe perinatal asphyxia. The authors present some case reports of asphyxiated newborns of different gestational age with different forms of NWS. Prenatal and perinatal asphyxia determines the prognosis of future development of newborn. The combination of the asphyxia and NWS is stressful not only for the patient, but also for the physician. The most important step in management of this group of patients is to know the detailed mother's and patient's history and to perform detailed physical investigation. The optimal prenatal, perinatal and postnatal management with good cooperation between gynecologist and neonatologist can improve the quality of newborn's life. Care of newborn requires all the time teamwork....

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Journal Article 2015; 36(Suppl 1): 150-155 PubMed PMID: 26757120 Citation  Keywords:  Animals, Cholinesterase Inhibitors:pharmacology, Electromyography, Female, Muscle, Smooth:drug effects, Stomach:drug effects, Sus scrofa, Tacrine:analogs & derivatives,.   

OBJECTIVES: Tacrine was the first acetylcholinesterase inhibitor approved for therapy of Alzheimer's disease. It has currently been withdrawn in some countries mostly due to the risk of hepatotoxicity and might be replaced by its derivate 7-methoxytacrine (7-MEOTA). The aim of this study was to assess the impact of these two compounds on gastric myoelectrical activity by means of surface cutaneous electrogastrography (EGG).

METHODS: Twelve pigs (Sus scrofa f. domestica, weighing 30-35 kg) entered the study. A single dose of tacrine (200 mg i.m., n=6) or 7-MEOTA (200 mg i.m., n=6) was administrated. All EGG recordings were performed under general anaesthesia in the morning after 24 hours of fasting. Basal (30 minutes) and study recordings (150 minutes) were accomplished using an EGG stand (MMS, Enschede, the Netherlands). Results were expressed as dominant frequency of gastric slow waves, power analysis (areas of amplitudes) and power ratio assessment (ratio of the areas of amplitudes after and before study drug administration).

RESULTS: Tacrine decreased EGG dominant frequency 10 minutes after its administration (from basal 3.1±0.6 to 2.8±0.6 cycles per minute; p=0.014). Tacrine induced a non-significant 60-minute increase of the power (with maximal value 493±533 μV2 at 20 minutes) and power ratio (with maximal value 2.04±3.4 at 10 minutes). Tacrine caused substantial gastric arrhythmia. 7-MEOTA did not influence dominant frequency of gastric slow waves significantly. 7-MEOTA caused a short-term late increase of the power ratio at 60 minutes (6.3±11.2; p=0.003). Blood cholinesterase activity did not correlate with any EGG parameter either after tacrine or 7-MEOTA at any time.

CONCLUSIONS: Tacrine and 7-MEOTA have different impacts on EGG. Tacrine decreased dominant frequency and induced long-lasting gastric arrhythmia. 7-MEOTA caused a short-term late increase of the EGG power in experimental pigs....

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Journal Article 2015; 36(Suppl 1): 68-72 PubMed PMID: 26757118 Citation  Keywords:  Animal Feed:analysis, Animals, Dogs, Food Contamination:analysis, Hair:chemistry, Mercury:analysis,.   

OBJECTIVES: The present work is aimed at assessing the mercury contamination of dogs through the analysis of hair. For the determination of the total mercury in dogs, we chose skin derivatives--hair. The content of total mercury was also measured in the pelleted feed.

METHODS: Dogs were divided into two groups. The first group (group A) was fed granular feed containing fish and the second group (group B) granular feed free of fish. A total of 131 hair and granular feed samples were collected. The total mercury in hair and granular feed samples was measured using atomic absorption spectrophotometry on AMA 254.

RESULTS: The values of the total mercury content in the hair of dogs had a median value of 0.0375 mg.kg(-1) in group A and of 0.0336 mg.kg(-1) in group B. No statistically significant difference was found between the groups (p>0.05). The median values of the total mercury were 0.0048 mg.kg(-1) in group A and 0.0017 mg.kg(-1) in group B, respectively. A highly statistically significant difference between the groups was found (p<0.01).

CONCLUSIONS: No correlation was obtained between the total mercury content in the hair of dogs and granulated feed (rs=0.2069, p>0.05). The reason may be a content of various mercury species in feed samples or a human failure (nonobservance of the prescribed diet)....

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