Detection of bemitil and its metabolite in urine by means of LC-MS/MS in view of doping control analysis.

2-(Ethylthio) benzimidazole is an active ingredient of Antihot, a dietary supplement sold in Ukraine. The substance, available also under names of Bemitil, Metaprot, and Bemaktor, was developed in the USSR in 1970s, and after tests on Soviet cosmonauts and soldiers, several studies on its influence on athletes' performances were conducted. The research showed that bemitil is a synthetic adaptogen which is capable to significantly increase physical performance and reduce the time of regeneration.

The influence of caffeine on ethyl glucuronide levels in rat serum and in rat hair.

Background: Ethanol and caffeine are the most widely used psychoactive substances in the world, with an observed steady increase in the combined consumption of alcohol and caffeine. Specific signs of ethanol-caffeine interactions have been reported both in humans and in animals. The metabolic effects of these interactions have not been fully elucidated.

Analysis for higenamine in urine by means of ultra-high-performance liquid chromatography-tandem mass spectrometry: Interpretation of results.

Higenamine (Norcoclaurine) is a very popular substance in Chinese medicine and is present in many plants. The substance may be also found in supplements or nutrients, consumption of which may result in violation of anti-doping rules. Higenamine is prohibited in sport at all times and included in Class S3 (β-2-agonists) of the World Anti-Doping Agency (WADA) 2017 Prohibited List.

Comparison of Chemical Composition in Tuber aestivum Vittad. of Different Geographical Origin.

Truffles are prized and nutrition-rich edible hypogeous fungi. The aim of this study was a comprehensive investigation of chemical composition of Burgundy truffle (Tuber aestivum Vittad.).

THE EFFECT OF METHANOL USED AS VEHICULUM ON SERUM PHENACETIN CONCENTRATION IN THE RAT.

The xenobiotic absorption process is dependent on many factors, related both to the substance and form of its administration. During administration of small amounts of drugs, the effect of vehiculum on drug fate in the body becomes also evident. The intensity of absorption depends on numerous factors not necessarily related to the substance and its formulation, and also on biotransformation and active transport processes.

A Search for the Optimum Selenium Source to Obtain Mushroom-Derived Chemopreventive Preparations.

The objective of this research was to test whether selenium-yeast (Se-yeast) is a better source of selenium than sodium selenite for accumulation in mycelia and immunoactive cell wall polysaccharides. Culture media were enriched in selenium to a concentration of 20 µg/mL. Selenium was added to the medium either in the form of sodium selenite or in form of Se-yeast (Sel-Plex; Alltech Inc.

EXCRETION OF ETHYL GLUCURONIDE IN THE URINE OF WARSAW HIGH PREFERRING RATS DEPENDS ON THE CONCENTRATION OF INGESTED ETHANOL.

Ethyl glucuronide (EtG) is a direct ethanol metabolite. The presence of EtG in urine can be used as a laboratory test to detect recent alcohol consumption. Several earlier studies in humans and in rats revealed that the same amount of ethanol ingested at different concentrations results in different blood ethanol concen- trations.

QUINIDINE AND DOMPERIDONE INTERACTIONS IN THE RAT EXPERIMENTAL MODEL OF REPEATED ADMINISTRATION.

This study has investigated domperidone (DOM) and quinidine (QD) interaction in the Wistar rat experimental model of repeated administration. We used nonconventional administration model consistent with occasional administration method. Difference in administration was related to sequence of domperidone alone or with quinidine dosage.

Efficient strategy for the selective determination of dopamine in human urine by molecularly imprinted solid-phase extraction.

An efficient molecularly imprinted solid-phase extraction protocol was developed for the separation of dopamine (DA) from human urine. After successful validation of the analytical method using high-performance liquid chromatography coupled with fluorescence detection, a new strategy for the selective determination of DA in the presence of norepinephrine and epinephrine in human urine was presented. In the proposed protocol, the LODs and quantification for DA were 166 ± 36 and 500 ± 110 nmol/L, respectively, and the total recoveries of DA in the range of 1-15 μmol/L varied between 98.

Deposition of ethyl glucuronide in WHP rat hair after chronic ethanol intake.

Background: This study investigated the relationship between ethanol intake in rats and the resulting level of ethyl glucuronide (EtG) in rat hair.

Methods: Rats (n = 50) consumed a 10% ethanol solution for 4 weeks, then EtG was extracted from samples of their hair using a novel extraction procedure involving freezing and thawing. The EtG concentration was measured using gas chromatography and mass spectrometry.

Multiplicity of n-heptane oxidation pathways catalyzed by cytochrome P450.

Modeling, mutagenesis, and kinetic studies have demonstrated that the substrate-binding site of cytochrome P450 is composed of multiple interactive regions that are capable of simultaneously binding two or more xenobiotics. Substrate molecules can interact with each other after docking. Thus, substrates can compete for the activated oxygen-ferrous complex or alter the spatial orientation of other molecules.

Impact of the changes in P-glycoprotein activity on domperidone pharmacokinetics in rat plasma.

The effect of quinidine (QD) and grapefruit juice (GFJ) extract, P-glycoprotein inhibitors, on the domperidone (DOM) concentration in rat plasma was investigated. DOM, a dopamine D(2)-receptor antagonist is a substrate for P-glycoprotein. DOM(10 mg/kg) was administered orally 2 h after GFJ extract (0.

Dopamine-imprinted polymers: template-monomer interactions, analysis of template removal and application to solid phase extraction.

A dopamine-imprinted polymer (MIP) was prepared in aqueous methanol solution at 60(o)C by free-radical cross-linking polymerization of methacrylic acid in the presence of ethylene glycol dimethacrylate as the cross-linker and dopamine hydrochloride as the template molecule. Its ability to isolate dopamine was evaluated as the basis of a solid phase extraction procedure and compared with that of a non-imprinted polymer(NIP). The binding of dopamine was 84.

Cypermethrin alters Glial Fibrillary Acidic Protein levels in the rat brain.

Pyrethroids, widely used insecticides, are biologically active in neurons. Whether they act on the non-neuronal brain cells remains an open question. Thus, the aim of this study was to examine whether Cypermethrin intoxication affects astroglial cells in the rat brain.

Polychlorinated biphenyls alter expression of alpha-synuclein, synaptophysin and parkin in the rat brain.

Polychlorinated Biphenyls (PCBs)-induced changes in synaptic transmission are one of the effects of their neurotoxicity but the mechanism remains unknown. We assessed the in vivo effects of the PCBs mixture, Aroclor 1254 on the expression of neuronal proteins that are involved in the synaptic function and/or are associated with neurodegeneration. Wistar rats were treated orally with repeated doses of Aroclor 1254 and the levels of soluble alpha-synuclein, parkin, synaptophysin and amyloid precursor protein (APP) in the brain were determined by Western blotting.

In vivo effect of 5- and 8-methoxypsoralens and cimetidine on R,S-warfarin metabolism in rat.

Several forms of cytochrome P-450 (CYP) metabolize R,S-warfarin in a regio- and enantioselective manner, therefore R,S-warfarin can be recognized as a metabolic probe for a number of CYP isoforms. We have applied a warfarin model in vivo in order to estimate the inhibitory properties of 5- and 8-methoxypsoralens on the activity of rat CYP isoforms. The area under the serum concentration versus time curve (AUC) values from time zero to 5 h for R- and S-warfarin and their metabolites were calculated.

In vivo effect of diallyl sulfide and cimetidine on phenacetin metabolism and bioavailability in rat.

Numerous cytochrome P450 inhibitors have been described as effective modulators of cytochrome P450 isoforms activity in vitro. Their inhibitory efficiency may be considerably modified after in vivo application. The aim of this study was to examine the effect of oral administration of diallyl sulfide--a cytochrome P450 2E1 inhibitor and cimetidine--a cytochrome P450 2C6 and 2C11 inhibitor on rat serum concentration of phenacetin and its metabolite acetaminophen.

Enhancement of alcohol-induced hypoglycaemia by H2-receptor antagonists.

The oral ethanol loading test (0.5 g/kg body mass) was carried out in 3 groups with 10 healthy male volunteers each before and after 7 days of administration of either cimetidine (CAS 51481-61-9), ranitidine (CAS 66357-59-3), or famotidine (CAS 76824-35-6). The parameters determined during 6 h comprised the blood levels of ethanol, acetaldehyde, glucose, lactate, pyruvate and bicarbonates, as well as blood pH, PCO2 and PO2.

Alcohol tolerance in patients with non-insulin-dependent (type 2) diabetes treated with sulphonylurea derivatives.

The oral ethanol loading test (0.5 g/kg body mass given as 40% solution) was carried out in 5 groups, each of 10 out-patients with non-insulin-dependent (type 2) diabetes before and after 10 days of treatment with one of the following sulphonylurea derivatives: tolbutamide (CAS 64-77-7) 0.5 t.

[Alcohol tolerance in patients with non-insulin-dependent diabetes (type 2) treated orally with drugs--derivatives of sulphonylurea].

The oral ethanol loading test (0.5 g per kg b.m.

[Spectral interactions of cytochrome P-450 with n-heptane and methanol].

Methanol interacts with cytochrome P-450 to produce the reversed type I spectral change. In the presence of type I substrate n-heptane, the methanol induced spectrum disappears without detectable effects of interaction suggesting that methanol is a very weak ligand for heme iron of cytochrome P-450. Methanol strongly lowers the apparent spectral dissociation constant (Ks app) of n-heptane binding with rat liver cytochrome P-450 both in control and C6-C9 petroleum fraction inhaled group.

[Specificity of cytochrome P-450 forms in the rat liver after inhalation of multicomponent hydrocarbon mixture].

Rats were inhaled with C6-C9 petroleum fraction 12 hrs daily for 9 days. The hydrocarbons and their metabolites gas chromatographic profiles from liver, kidney, brain and blood were investigated by means of head space technique. The observed characteristic profile composed of some hydrocarbons and secondary alcohols does not undergo qualitative changes and internal quantitative proportions remain constant in spite of cytochrome P-450 induction.

Effect of two-week ethanol administration on lipoprotein lipase activity and blood serum lipids in the rat.

Influence of ethanol administration on adipose tissue lipoprotein lipase activity, serum lipids in the rat. Intoxication caused a decrease of lipoprotein lipase activity. In some animals a rise of serum high density lipoprotein cholesterol was observed which correlated positively with the content of cytochrome P-450 in the liver.