Determination of three anabolic compounds in calf urine by liquid chromatography with photodiode-array detection

Oral exposure of rats to dienestrol during gestation and lactation: Effects on the reproductive system of male offspring

This study was aimed at determining whether dienestrol (DIES) affects reproduction in male offspring of rats following oral maternal exposure during gestation and lactation. Pregnant rats were treated from GD 6 to PND 21. Animals received 0 (control-vehicle), 0.75, 1.5, 3.12, 6.25, 12.5, 50, 75 μg/kg bw/d of DIES. A control group -without vehicle-was also included. High DIES concentrations caused abortions at 75 and 50 μg/kg bw/d, while at 12.5 μg/kg bw/d had still miscarriages. Ten male rats per group were kept alive until PND 90 to ensure sexual maturity. Body and organ weights, anogenital distance (AGD) at PNDs 21 and 90, biochemical and sperm parameters like motility, viability, morphology, spermatozoa and resistant spermatid counts, and histopathology for sexual organs and liver were determined. An increase in organ weight (liver and sexual organs) and a decrease in AGD due to vehicle were found. A reduction of sperm motility and viability, and an increase of abnormal sperm morphology were caused by DIES, which provoked a dose-dependent prostatitis. Maternal exposure to DIES induced toxicity on the reproductive system of the male offspring, which could affect the capacity of fertilization.

A downscaled multi-residue strategy for detection of anabolic steroids in bovine urine using gas chromatography tandem mass spectrometry (GC–MS3)

Within the scope of the European Community member states' residue monitoring plan, illicit administration of anabolic steroids is monitored at slaughterhouse level as well as on living animals. At farm level, urine is one of the target matrices to detect possible abuse of anabolic steroid growth promoters. Optimisation of the routinely applied analysis method resulted in a procedure for which high performance liquid chromatographic (HPLC) fractionation prior to GC-MS(n) analysis was no longer required. Analytical results could be obtained within 1 day and only 5 mL urine was needed to carry out the screening procedure. Using the downscaled methodology, all validation criteria described in the European Commission document 2002/657/EC could be fulfilled, and the minimum required performance limits (MRPLs) established for anabolic steroids in urine, could be achieved. A higher GC-MS technique's specificity was achieved by detecting the steroids using GC-MS3. Nevertheless, it was decided to screen routinely sampled urine with GC-MS2 whereas GC-MS3 was applied to confirm the presence of anabolic steroid residues in suspected sample extracts.

Quantitation of seven polyoxypregnane glycosides in Marsdenia tenacissima using reversed-phase high-performance liquid chromatography-evaporative light-scattering detection

A high-performance liquid chromatography coupled with an evaporative light scattering detector (HPLC-ELSD) has been developed for the simultaneous determination of seven polyoxypregnane glycosides, tenacissosides A, B, G, H, I and marsdenosides C, G, in the stem of Marsdenia tenacissima, a Chinese herbal medicine. With a C18 analytical column, the analytes were separated efficiently using methanol-water as the mobile phase in a gradient program. The method limits of detection ranged from ca. 0.3 microg for marsdenoside C to ca. 0.5 microg for marsdenoside G and the method limits of quantitation from 1.0 microg for marsdenoside C to 1.7 microg for marsdenoside G, respectively. The intra- and inter-day precisions of the method were evaluated and all were less than 4%. All the recoveries for the spiked analytes exceeded 90%. This method was successfully used to analyze 19 samples of the stem of M. tenacissima.

Lectin binding patterns in hyperplastic and metaplastic bullock prostate tissues after diethylstilbestrol administration

Hyperplasia and squamous metaplasia of the prostatic epithelium are conditions induced by oestrogens. Diethylstilbestrol (DES) has been banned from cattle used for beef production because of the health risks. The potential use of molecular markers for the detection of illegal oestrogen administration was evaluated by taking samples of prostatic tissue from control bullocks, bullocks which had been treated with oestrogens, and bullocks sacrificed 21 and 90 days after a single dose of DES. The expression of the glycoconjugates was examined by lectinhistochemistry and the lectin binding pattern was characterised in epithelium and connective tissue. In the animals sacrificed after 21 days there was an increase in the binding of one lectin (JAC) and there was an increase in the binding of one of the other lectins (DBA) in the animals sacrificed after 90 days. An increase in SWGA lectin staining was observed in the bullocks that had probably been treated with oestrogen and in the animals sacrificed 90 days after the inoculation with DES. There were also differences between the binding of SWGA in the control bullocks and the other groups.

Determination of trenbolone and its metabolite in bovine fluids by liquid chromatography-tandem mass spectrometry

A liquid chromatographic-tandem mass spectrometric (LC-MS-MS) method has been developed for the determination of trenbolone in bovine urine and serum. The aim was a control of the misuse of trenbolone in food-producing animals. The procedure involved, in both cases, a preliminary solid-phase clean-up followed by a liquid-liquid extraction for urine samples after a preliminary enzymatic hydrolysis. The extracts have been directly analysed by reversed-phase LC-MS-MS in selected reaction monitoring (SRM), acquiring two diagnostic product ions from the chosen precursor [M+H](+). The procedures were validated across the concentration range of 1-1500 ng/ml. The linearity, the inter- and intra-day accuracy and precision have been determined. The procedure was specific and the accuracy values were better than 20% at the limit of quantitation of spiked samples. The limit of quantification (LOQ) and the limit of detection (LOD) were, respectively, 1 ng/ml and 350 pg/ml for urine and serum. According to the draft, SANCO/1805/2000, we determined the decision limit CCalpha and the detection capability CCbeta. The recovery values for urine ranged from 87 to 128%, and for plasma the recovery was 70+/-4%. The procedure proved to be simple and suitable for routine and confirmatory purposes such as those developed for residue studies.

Method for determining monohydroxybenzo[a]pyrene isomers using column-switching high-performance liquid chromatography

A method for determining monohydroxybenzo[a]pyrene (OHBaP) isomers using column-switching high-performance liquid chromatography with fluorescence detection was developed. Eleven of 12 isomers of OHBaP (all except 6-OHBaP) were separated on an alkylamide-type reversed-phase column and, via column-switching, on a beta-cyclodextrin-bonded silica gel column. The detection limits for the OHBaPs were in the range 0.3-8 pg/injection (S/N=3). By using this method, 1-, 3-, and 9-OHBaPs were identified as major metabolites of benzo[a]pyrene in vitro by human recombinant p450 1A1. The method was used to determine OHBaPs in the urine of a nonsmoker subject. After enzymatic hydrolysis of the conjugated metabolites by beta-glucuronidase/aryl sulfatase, the analytes were selectively adsorbed on blue rayon (a cellulose-supported copper phthalocyanine) from the urine matrix. Methanol as the eluting solvent from the rayon gave the best recoveries of OHBaPs and 1-hydroxypyrene (1-OHP) in the range of 91-103%, which was superior to that of the solid-phase extraction method. 1-OHP, a well-known biomarker of the exposure to polycyclic aromatic hydrocarbons, was simultaneously analyzed. Intra- and interday accuracy values for the determination of 3-OHBaP in 200 ml of urine were 95.5 and 100.9%, and those for 1-OHP were 96.4 and 103.6%, respectively. The intra- and interday precision values were 3.9 and 2.4% for 3-OHBaP and 2.4 and 3.2% for 1-OHP, respectively. In 11 kinds of isomers, only 3-OHBaP was detected in the human urine. Urinary concentration of 3-OHBaP was quantified at 0.5 ng/g creatinine concentration and the 3-OHBaP/1-OHP ratio was approximately 1/130.

Determination of 1-hydroxypyrene in human urine by high-performance liquid chromatography with fluorescence detection using a deuterated internal standard

A high-performance liquid chromatographic method has been developed for the quantification of 1-hydroxypyrene (1-OHP) in human urine using deuterated 1-hydroxypyrene ([2H9]1-OHP) as an internal standard with fluorescence detection. [2H9]1-OHP was prepared enzymatically from deuterated pyrene ([2H10]Pyr) with cytochrome P450 1A1. It eluted immediately prior to non-deuterated 1-OHP on alkylamide-type reversed-phase columns and had nearly the same fluorescence characteristics as non-deuterated 1-OHP. The detection limit was 0.1 microg/L and the calibration range was from 1 to 100 nmol/L. Urine sample treatment involved enzymatic hydrolysis followed by solid-phase extraction using Sep-Pak C18 cartridges. The proposed method was used to determine urinary 1-OHP in smokers and non-smokers.