The potential of urinary androstdiene markers to identify 4-androstenediol (4-ADIOL) administration in athletes.

Doping control laboratories accredited by the World Anti-Doping Agency (WADA) require criteria that allow endogenous steroids to be distinguished from their synthetic analogues in urine. Methodology based on "looking outside the metabolic box" was used in this study to identify diagnostic urinary markers of 4-androstenediol (4-ADIOL) administration. Androst-2,4-diene-17-one and androst-3,5-diene-17-one are proposed to be formed in urine from acid-catalyzed hydrolysis of 4-ADIOL sulfoconjugate, a major phase II metabolic product of 4-ADIOL.

Screening for testosterone abuse in male athletes using the measurement of urinary LH, a revision of the paradigm.

The primary screening method for the detection of doping by athletes using synthetic versions of endogenous steroids such as testosterone relies on measurement of the ratio of testosterone (T) to epitestosterone (E) in urine. In 2005 the World Anti-Doping Agency (WADA) lowered the T/E value at which samples undergo further investigation from six to four. This has resulted in a large increase in the number of athletes with naturally elevated T/E ratios undergoing investigation without a corresponding increase in the number of proven doping offences involving testosterone.

Effects of recombinant human LH and hCG on serum and urine LH and androgens in men.

Context: The administration of gonadotrophins is prohibited in sport but the effect in men of recently available recombinant hCG and LH on serum and urine concentrations of gonadotrophins and androgens has not been systematically evaluated in the antidoping context.

Objective: To determine the time-course of recombinant LH (rhLH) and hCG (rhCG) on blood and urine hormone profiles in men to develop effective tests to detect rhLH and rhCG doping.

Design: Two randomized controlled studies with a 2 x 2 factorial design.

Carbon isotope ratio (delta13C) values of urinary steroids for doping control in sport.

The detection of steroids originating from synthetic precursors in relation to their chemically identical natural analogues has proven to be a significant challenge for doping control laboratories accredited by the World Anti-Doping Agency (WADA). Endogenous steroid abuse may be confirmed by utilising the atomic specificity of gas chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS) that enables the precise measurement of differences in stable isotope ratios that arise as a result of fractionation patterns inherent in the source of steroids. A comprehensive carbon isotope ratio (delta(13)C) profiling study (n=1262) of urinary ketosteroids is reported that demonstrates the inter-individual variation that can be expected from factors such as diet, ethnicity, gender and age within and between different populations (13 countries).

The detection of androstenedione abuse in sport: a mass spectrometry strategy to identify the 4-hydroxyandrostenedione metabolite.

Studies have shown that the administration of androstenedione (ADIONE) significantly increases the urinary ratio of testosterone glucuronide to epitestosterone glucuronide (T/E) - measured by gas chromatography/mass spectrometry (GC/MS) - in subjects with a normal ( approximately 1) or naturally high (>1) initial values. However, the urinary T/E ratio has been shown not to increase in subjects with naturally low (<1) initial values. Such cases then rely on the detection of C(6)-hydroxylated metabolites shown to be indicative of ADIONE administration.

Determination of urinary steroid sulfate metabolites using ion paired extraction.

The need for laboratories accredited by the World Anti-Doping Agency (WADA) to develop methods of analysis for steroids excreted primarily as their sulfate conjugates has faced significant analytical challenges. One of the issues relates to the extraction of these metabolites from urine in a relatively pure state. The use of (-)-N,N-dimethylephedrinium bromide as an ion pairing reagent was optimised to produce a method that is selective for the extraction of steroid sulfates prior to GC-MS or LC-MS analysis, with minimal contributions from the urine matrix.

Methodologies for detection of hemoglobin-based oxygen carriers.

Blood substitutes based on hemoglobin or hemoglobin-based oxygen carriers (HBOCs) are oxygen-carrying therapeutic agents developed for use in operations and emergencies in place of donated blood. Increased oxygen-carrying capacity through the use of blood substitutes could help elite athletes to lengthen endurance capacity and improve their performance. As blood substitutes become more readily available, it is essential that a qualitative detection method for their abuse in sport is available.

Isotopic fractionation of endogenous anabolic androgenic steroids and its relationship to doping control in sports.

The use of gas chromatography (GC)-combustion (C)-isotope ratio mass spectrometry (IRMS) demonstrates that a single oral administration of dehydroepiandrosterone (DHEA, 100 mg) to a male subject significantly lowers the 13C content of etiocholanolone (Et) and androsterone (A) in the subject's urine. The difference in carbon isotope ratio (d13C per thousand) values between Et and A increases from 1.6 per thousand at the time of administration to 5.

Sports drug testing--an analyst's perspective.

Sport plays a major role in the lives of many people, both for active participation and as entertainment. Sport is now a huge nationally and internationally based industry. The desire to win has led some athletes to resort to the use of performance enhancing drugs.

The influence of the rate of pH decline on the rate of ageing for pork. II: Interaction with chilling temperature.

The influence of the rate of pH decline post slaughter on the rate of ageing of pork m. longissimus thoracis et lomborum was investigated. The rate of pH decline on 24 finisher pigs was manipulated by altering the method of stunning (carbon dioxide or electrical head to heart) and by the use of electrical stimulation (none or low voltage electrical stimulation (LVES) at 4 min post slaughter for either 15 s or 60 s).

The influence of the rate of pH decline on the rate of ageing for pork. I: interaction with method of suspension.

The influence of the rate of pH decline post slaughter on the rate of ageing of pork was investigated. The rate of pH decline on 24 finisher pigs was manipulated by altering the method of stunning (carbon dioxide or electrical head to heart) and by the use of electrical stimulation (none or low voltage electrical stimulation (LVES) at 4 min post slaughter). To investigate the effect of pH decline rate on ageing rate independently of the effect on possible muscle shortening, sides were suspended by either the pelvis (to minimize shortening) or conventionally by the Achilles tendon.

Second-generation blood tests to detect erythropoietin abuse by athletes.

Background And Objectives: We previously developed blood tests that were introduced at the Sydney 2000 Olympic Games to identify athletes injecting recombinant human erythropoietin (rHuEPO). The aim of this study was to re-analyse our existing database to develop models with heightened sensitivity, using wherever possible blood parameters measurable with appropriate standards of analytical performance.

Design And Methods: The principal database for this study was derived from a double-blind trial in which 57 recreational athletes were administered either rHuEPO or placebo.

Development of reference ranges in elite athletes for markers of altered erythropoiesis.

Background And Objectives: Our previous research developed two statistical models that are useful indicators of current (ON-model) or recently discontinued (OFF-model) recombinant human erythropoietin (rHuEPO) use by athletes. The component variables of the ON-model are hematocrit (Hct), reticulocyte hematocrit (RetHct), serum erythropoietin (EPO), percent macrocytes (%Macro), and soluble transferrin receptor (sTfr), whilst the OFF-model uses only the first three variables. Genetics and training modalities of elite athletes may conceivably produce unusual values for blood parameters related to erythropoiesis.

Antioxidant effects of rosemary extract and whey powder on the oxidative stability of wiener sausages during 10 months frozen storage.

Twelve (Large White×Landrace) gilts were randomly allotted in a 2×2 factorial design with the respective factors being dietary vitamin E (10 or 200 mg/kg feed) and dietary fishmeal (0 or 5%). Wiener sausages were manufactured with or without antioxidants such as rosemary extract and sweet whey powder from meat obtained from the animals after slaughter and stored for 5 days at 4 °C. The oxidative stability of the wieners was examined over ten months of frozen storage.

Physiological and pharmacological regulation of 20-kDa growth hormone.

The 20-kDa growth hormone (GH) is generated from alternative splicing of the primary transcript of full-length 22-kDa GH. We have studied the regulation of 20-kDa GH over a range of pathophysiological conditions and in response to pharmacological stimulation using isoform-specific enzyme-linked immunosorbent assays (ELISAs). Mean 24-h levels of 20- and 22-kDa GH were higher in acromegaly and lower in GH deficiency than in normal subjects, with the 20-to-22-kDa ratio not different between the three groups.

Effect of dietary vitamin E, fishmeal and wood and liquid smoke on the oxidative stability of bacon during 16 weeks' frozen storage.

Twelve (Large White×Landrace) gilts were randomly allotted in a 2×2 factorial design with the respective factor being dietary vitamin E (10 or 200 mg/kg feed) and dietary fishmeal (0 or 5%). Bacon was manufactured from the meat obtained from the animals after slaughter using wood smoke only or a combination of liquid and wood smoke. The oxidative stability of the bacon was examined over 16 weeks of frozen storage.

Effect of tocopherol concentration on rancidity development during frozen storage of a cured and an uncured processed pork product.

This research evaluated the effect of addition during processing of various concentrations of tocopherol (0-1000 mg/kg) on the subsequent lipid oxidation and rancidity development during frozen storage of two pork products-a coarsely ground cured sausage and an uncured restructured pork roast. The results indicated that tocopherol had little effect on lipid oxidation, as measured by TBARS values and sensory evaluation during frozen storage at -18 °C for 37 weeks for either product. However, lipid oxidation only occurred to a limited extent even in products without tocopherol and was insufficient to cause rancid flavour development.

Strategies for rhEPO detection in sport.

This article examines available strategies for the detection of recombinant erythropoietin (rhEPO) abuse in sport. RhEPO was quickly recognized as an effective but hazardous performance-enhancing agent. In the absence of a valid procedure to detect rhEPO doping, at-competition health checks were introduced, which excluded athletes from competition when their hemoglobin or hematocrit values exceeded an arbitrary limit.

Tenderness of pork m. longissimus thoracis et lumborum after accelerated boning. Part II. Effect of post-slaughter ageing.

This research investigated the effect of ageing time (0-10 days) at 2 °C on tenderness of pork longissimus muscle after either rigor boning (RB) or accelerated boning (removal from carcass within 30 min post slaughter) and temperature conditioning at either 0 or 14 °C. Ageing occurred most rapidly in muscles conditioned at 14 °C- maximum tenderization occurred by 4 days post-mortem. RB muscles and muscles conditioned at 0 °C aged more slowly and took 8 and 10 days, respectively, to reach a comparable level of tenderness.

Tenderness of pork m. longissimus thoracis et lumborum after accelerated boning. Part I. Effect of temperature conditioning.

This research investigated the effect on tenderness and meat quality of temperature conditioning at 0, 7, 14 or 21 °C of pork longissimus muscle after accelerated boning (removal from the carcass within 30 min post slaughter). The conditioning temperature had no effect (P>0.05) on tenderness at the end of the conditioning period (i.

Effect of calcium infusion on tenderness and ageing rate of pork m. longissimus thoracis et lumborum after accelerated boning.

The effect of calcium chloride infusion at either 0.5 or 6 h post slaughter on tenderness, ageing rate and meat quality of pork longissimus muscle that had been boned at rigor or had undergone accelerated processing and conditioning at either 0 °C or 14 °C was investigated. The time of calcium infusion had no effect on the initial WBSF values or the aging rate.

Temperature and pH dependence of the autoxidation rate of bovine, ovine, porcine, and cervine oxymyoglobin isolated from three different muscles--Longissimus dorsi, Gluteus medius, and Biceps femoris.

This study examined the temperature and pH dependence of the in vitro autoxidation rate of bovine, ovine, porcine, and cervine oxymyoglobin that had been isolated and purified from three muscles of different oxidative stability--Longissimus dorsi, Gluteus medius, and Biceps femoris. To avoid obtaining unreliable estimates of autoxidation rate as has occurred in many previous studies, in this study, precautions were taken to eliminate the effects of freezing, chemical reduction with hydrosulfite, and contaminating metal ions on the reaction rate. When these precautions were taken, the rate constants for the different myoglobins studied were similar to each other but were 2-7-fold lower, and the Ea (activation energy) was 20-100% higher than that reported in most previous studies.

Tenderness, ageing rate and meat quality of pork M. longissimus thoracis et lumborum after accelerated boning.

The impact of accelerated boning on tenderness, ageing rate and meat quality of pork longissimus muscle was investigated. Accelerated boning of eight Large White×Landrace pork carcasses at 30 min post-mortem followed by chilling at 0°C resulted in tougher pork with higher drip loss and a darker surface lightness relative to conventional boning at 24 h post-mortem. The increased toughness was still observed at 4 days post-mortem, a time by which 80% of ageing generally had occurred as seen in experiment 2.