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1.
Drug Test Anal ; 8(11-12): 1119-1130, 2016 Nov.
Article in English | MEDLINE | ID: mdl-27390252

ABSTRACT

To minimize the chances of being caught after doping with recombinant human erythropoietins (rhEPO), athletes have turned to new practices using micro-doses and excess fluid ingestion to accelerate elimination and decrease the probability of detection. Our objective was to test the sensitivity of detection by validated methods (IEF: isoelectric focusing; SDS-PAGE: sodium dodecyl sulfate polyacrylamide gel electrophoresis) when such practices are used. First, after a three-week rhEPO boost period and 10 days of wash out, detection of a single 900 IU micro-dose of Eprex® was evaluated in healthy male subjects. After an injection in the evening, urine and plasma samples were collected the following morning. Half of the subjects then drank a bolus of water and new samples were collected 80 min later. Interestingly, rhEPO was detected in 100% of the samples even after water ingestion. A second similar protocol was then performed with a single injection of a micro-dose of rhEPO (500 IU or 900 IU), without a prior rhEPO boost. In addition, urine and plasma samples were also collected 15 and 20 h post rhEPO administration. Once again drinking water did not affect the rate of detection. Urine appeared a better matrix to detect micro-doses after 10 h, enabling between 92% and 100% of identification at that time. The rate of identification decreased rapidly thereafter, in particular for the 500 IU micro-dose. However IEF analysis still resulted in 71% identification of rhEPO in urine after 20 h. These results could help to define a better strategy for controlling and identifying athletes using rhEPO micro-doses. Copyright © 2016 John Wiley & Sons, Ltd.


Subject(s)
Electrophoresis, Polyacrylamide Gel/methods , Erythropoietin/blood , Erythropoietin/urine , Isoelectric Focusing/methods , Recombinant Proteins/blood , Recombinant Proteins/urine , Substance Abuse Detection/methods , Erythropoietin/metabolism , Humans , Recombinant Proteins/metabolism
2.
Eur J Pain ; 20(8): 1241-52, 2016 09.
Article in English | MEDLINE | ID: mdl-26919333

ABSTRACT

BACKGROUND: Knowledge about the course of recovery after whiplash injury is important. Most valuable is identification of prognostic factors that may be reversed by intervention. The mutual maintenance model outlines how post-traumatic stress symptoms (PTSS) and pain may be mutually maintained by attention bias, fear, negative affect and avoidance behaviours. In a similar vein, the fear-avoidance model describes how pain-catastrophizing (PCS), fear-avoidance beliefs (FA) and depression may result in persistent pain. These mechanisms still need to be investigated longitudinally in a whiplash cohort. METHODS: A longitudinal cohort design was used to assess patients for pain intensity and psychological distress after whiplash injury. Consecutive patients were all contacted within 3 weeks after their whiplash injury (n = 198). Follow-up questionnaires were sent 3 and 6 months post-injury. Latent Growth Mixture Modelling was used to identify distinct trajectories of recovery from pain. RESULTS: Five distinct trajectories were identified. Six months post-injury, 64.6% could be classified as recovered and 35.4% as non-recovered. The non-recovered (the medium stable, high stable and very high stable trajectories) displayed significantly higher levels of PTSS, PCS, FA and depression at all time points compared to the recovered trajectories. Importantly, PCS and FA mediated the effect of PTSS on pain intensity. CONCLUSIONS: The present study adds important knowledge about the development of psychological distress and pain after whiplash injury. The finding, that PCS and FA mediated the effect of PTSS on pain intensity is a novel finding with important implications for prevention and management of whiplash-associated disorders. WHAT DOES THIS STUDY ADD?: The study confirms the mechanisms as outlined in the fear-avoidance model and the mutual maintenance model. The study adds important knowledge of pain-catastrophizing and fear-avoidance beliefs as mediating mechanisms in the effect of post-traumatic stress on pain intensity. Hence, cognitive behavioural techniques targeting avoidance behaviour and catastrophizing may be beneficial preventing the development of chronic pain.


Subject(s)
Avoidance Learning , Catastrophization/psychology , Fear/psychology , Pain/psychology , Stress Disorders, Post-Traumatic/psychology , Whiplash Injuries/psychology , Adult , Cohort Studies , Female , Humans , Male , Middle Aged , Pain/diagnosis , Pain/etiology , Pain Measurement , Surveys and Questionnaires , Whiplash Injuries/complications , Young Adult
3.
Scand J Med Sci Sports ; 26(3): 338-47, 2016 Mar.
Article in English | MEDLINE | ID: mdl-25773052

ABSTRACT

Anecdotal evidence suggests that athletes hyperhydrate to mask prohibited substances in urine and potentially counteract suspicious fluctuations in blood parameters in the athlete biological passport (ABP). It is examined if acute hyperhydration changes parameters included in the ABP. Twenty subjects received recombinant human erythropoietin (rhEPO) for 3 weeks. After 10 days of rhEPO washout, 10 subjects ingested normal amount of water (∼ 270 mL), whereas the remaining 10 ingested a 1000 mL bolus of water. Blood variables were measured 20, 40, 60, and 80 min after ingestion. Three days later, the subjects were crossed-over with regard to water ingestion and the procedure was repeated. OFF-hr was reduced by ∼ 4%, ∼ 3%, and ∼ 2% at 40, 60, and 80 min, respectively, after drinking 1000 mL of water, compared with normal water ingestion (P < 0.05). Forty percent of the subjects were identified with atypical blood profiles (99% specificity level) before drinking 1000 mL of water, whereas 11% (n = 18), 10% and 11% (n = 18) were identified 40, 60, and 80 min, respectively, after ingestion. This was different (P < 0.05) compared with normal water intake, where 45% of the subjects were identified before ingestion, and 54% (n = 19), 45%, and 47% (n = 19) were identified 40, 60, and 80 min, respectively, after ingestion. In conclusion, acute hyperhydration reduces ABP OFF-hr and reduces ABP sensitivity.


Subject(s)
Doping in Sports , Drinking , Erythropoietin/blood , Performance-Enhancing Substances/blood , Substance Abuse Detection/methods , Adult , Athletes , Cross-Over Studies , Drinking Water , Erythropoietin/administration & dosage , Humans , Male , Performance-Enhancing Substances/administration & dosage , Plasma Volume , Recombinant Proteins/administration & dosage , Recombinant Proteins/blood , Sensitivity and Specificity , Young Adult
4.
Diabetes Obes Metab ; 17(2): 207-10, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25406646

ABSTRACT

We determined the effects of exercise on pancreatic endocrine responses to metabolic stimuli in subjects with type 2 diabetes (T2D) and examined the influence of subjects' diabetic status. Fourteen subjects underwent a hyperglycaemic clamp with glucagon-like peptide-1 (GLP-1) infusion and arginine injection, the morning after a 1-h walk or no exercise. Subjects were stratified by high and low fasting plasma glucose (FPG) levels and by glycated haemoglobin (HbA1c) levels, as well as by current use/non-use of antidiabetic medication. In the entire cohort, exercise did not alter insulin secretion, while glucagon levels were increased in all clamp phases (p < 0.05 to <0.01). In subjects with low FPG levels, exercise increased GLP-1-stimulated insulin secretion (p < 0.05), with the same trend being observed for arginine (p = 0.08). The same trends were seen for subjects with low HbA1c levels. Furthermore, exercise increased GLP-1- and arginine-stimulated insulin secretion (p < 0.05) in subjects who were antidiabetic drug-naïve. Exercise-induced increases in insulin secretion are blunted in subjects with T2D with high rates of hyperglycaemia and in those using antidiabetic drugs.


Subject(s)
Blood Glucose/metabolism , Diabetes Mellitus, Type 2/metabolism , Exercise , Glucagon/metabolism , Hyperglycemia/prevention & control , Insulin/metabolism , Pancreas/metabolism , Arginine/administration & dosage , Diabetes Mellitus, Type 2/physiopathology , Diabetes Mellitus, Type 2/therapy , Fasting , Female , Glucagon-Like Peptide 1/administration & dosage , Glucose Clamp Technique , Humans , Infusions, Intravenous , Injections , Insulin/blood , Insulin Secretion , Male , Pancreas/physiopathology , Treatment Outcome
5.
Scand J Med Sci Sports ; 24(4): 634-41, 2014 Aug.
Article in English | MEDLINE | ID: mdl-23347069

ABSTRACT

The detection of recombinant human erythropoietin (rhEPO) is difficult and becomes more challenging when only microdoses are administered intravenously. Twenty-three subjects were divided into two groups: EPO group (n = 7) and CONTROL group (n = 16). Seven urine and blood samples per subject were collected at least 5 days apart to determine within- and between-subject standard deviations in the percentage of migrating isoforms by the MAIIA test. Six injections of 50 IU/kg bw (boosting dosage) of epoetin beta (Neorecormon, Roche Diagnostics, Hvidovre, Denmark) were performed intravenously during a 3-week period, followed by two microinjections of only 10 IU/kg bw. Blood and urine samples were collected 2, 6, 12, and 72 h after the microinjection, as well as 72 h after the last boosting dose. Sensitivities and specificities of the MAIIA test were examined by absolute and passport thresholds. Sensitivity was 100% for at least 12 h after the microinjection, with ∼30% of plasma samples still exceeding the 99.9% passport threshold 72 h after a microinjection. The specificity was higher for the passport approach compared to the absolute approach, but there were no differences in sensitivities between approaches or between specimens (urine and plasma). We conclude that the MAIIA test shows potential for detecting very small doses of rhEPO.


Subject(s)
Erythropoietin/blood , Erythropoietin/urine , Performance-Enhancing Substances/blood , Performance-Enhancing Substances/urine , Substance Abuse Detection/methods , Adult , Erythropoietin/administration & dosage , Exercise/physiology , Humans , Male , Performance-Enhancing Substances/administration & dosage , Protein Isoforms/blood , Protein Isoforms/urine , Recombinant Proteins/administration & dosage , Recombinant Proteins/blood , Recombinant Proteins/urine , Sensitivity and Specificity , Young Adult
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