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Serum EPO (serum + epo)
Selected AbstractsThe utility of immature reticulocyte fraction as an indicator of erythropoietic response to altitude training in elite cyclistsINTERNATIONAL JOURNAL OF LABORATORY HEMATOLOGY, Issue 1p2 2010V. S. NADARAJAN Summary Altitude training is sometimes employed by elite endurance athletes to improve their sea level performance. This improvement results from the increased red cell mass consequent upon the boost in erythropoietin (EPO) level that occurs as a response to the relatively hypoxic environment at high altitudes. We measured serum EPO levels together with various red cell and reticulocyte parameters including immature reticulocyte fraction (IRF) in eight national track-endurance cyclists, resident at sea-level, prior to and upon return from an altitude of approximately 1905 m. Reticulocytes and soluble transferrin receptor (sTfR) were significantly increased with reduction in ferritin levels immediately on return from high altitude indicating increased erythropoietic activity. IRF in particular showed a significant peak immediately on return but decline to sub-baseline levels by day 9, and recovery to baseline by day 16. Our results indicate that IRF is a sensitive marker of erythropoietic status in athletes undergoing altitude training and subsequent loss of EPO stimuli on return to sea level. [source] A sample distribution programme for erythropoietinINTERNATIONAL JOURNAL OF LABORATORY HEMATOLOGY, Issue 4 2006J. T. MARSDEN Summary A survey was sent to laboratories participating in the United Kingdom External Quality Assessment Service (UKNEQAS) Haematinics Scheme about the measurement of serum erythropoietin (EPO). Six laboratories, from a total of 120 that returned the survey, were measuring serum EPO concentrations by commercially available immunoassays on site in the United Kingdom. The workload of the laboratories varied from up to 100 specimens per month to more than 100 specimens analysed per week. All laboratories included control material in the assays and none of the laboratories was participating in an external quality assessment scheme for serum EPO. Four laboratories agreed to take part in the first sample distribution programme, with five and six laboratories participating in distributions 2 and 3 respectively. The results from eight kits were compared from the three distributions over a 2-year period. The serum EPO concentrations for the methods showed some variation across the range of 2.9,200 U/l when the serum EPO concentrations for each method were compared with the whole method mean. The results from this scheme have identified a role for an external quality assessment scheme for serum EPO measurements. [source] Erythropoietin-producing renal cell carcinoma in chronic hemodialysis patients: A report of two casesINTERNATIONAL JOURNAL OF UROLOGY, Issue 1 2003SHINICHI SAKAMOTO Abstract Erythropoietin (EPO)-producing renal cell carcinomas in two hemodialysis patients are reported. Despite deteriorated kidney function, these patients did not manifest anemia at diagnosis and their elevated serum EPO levels rapidly returned to within the normal range after nephrectomy. Immunohistochemical staining of the resected specimens showed production of erythropoietin in the tumor cells in one case and in the lining cells of the cyst wall in the other case. Renal cell carcinoma could cause an increase of blood hematocrit level in dialysis patients. [source] Serum eosinophil granule proteins predict asthma risk in allergic rhinitisALLERGY, Issue 5 2009L. P. Nielsen Background:, Allergic rhinitis is a common disease, in which some patients will deteriorate or develop asthma. It is important to characterize these patients, thereby offering the possibility for prevention. This study evaluated eosinophil parameters as potential indicators of deteriorating allergic airway disease. Methods:, The subjects of the study included all patients who suffered seasonal allergic rhinitis and had participated in a study 6 years earlier, in which blood eosinophils, serum eosinophil cationic protein (ECP) serum eosinophil peroxidase (EPO), nasal lavage ECP and nasal lavage EPO levels were measured. Patients in the present study were interviewed on occurrence of rhinitis symptoms during the last season, rhinitis outside season, asthma-like symptoms and asthma diagnosis, and were skin-prick tested for common aeroallergens. Eosinophil parameters from the study 6 years earlier were then tested for the ability to predict occurrence of new allergies, worsening of rhinitis and occurrence of asthma. Results:, Forty-four patients participated in the study. In four patients seasonal rhinitis symptoms had deteriorated, 10 had experienced perennial rhinitis symptoms, 14 reported asthma-like symptoms and seven had been diagnosed with asthma. Thirteen had developed additional sensitization. Patients developing asthma-like symptoms compared with patients with no such symptoms had significantly higher serum ECP (16.7 ,g/l vs 8.2 ,g/l; P , 0.01) and serum EPO (17.9 ,g/l vs 8.8 ,g/l; P , 0.05). Results were similar, considering patients diagnosed with asthma. Blood eosinophils and nasal lavage parameters were not related to development of asthma and asthma-like symptoms. No eosinophil parameter was related to deterioration of rhinitis or additional sensitization. Conclusion:, Serum ECP and EPO in patients with seasonal rhinitis demonstrated a high predictive ability for later development of asthma. [source] Erythropoietin administration does not influence the GH,IGF axis or makers of bone turnover in recreational athletesCLINICAL ENDOCRINOLOGY, Issue 3 2005A. E. Nelson Summary Objective, Measurement of biochemical markers of the IGF-system and of collagen turnover is a potential approach to detect GH abuse in sport. These markers are increased in patients on dialysis treated with recombinant human erythropoietin (r-HuEPO), mimicking the effects of GH. The aim was to determine whether r-HuEPO induces similar effects on the IGF-system and collagen turnover in healthy athletes. Subjects and measurements, Young male Caucasian recreational athletes were administered 50 U/kg r-HuEPO (n = 14) or placebo (n = 16) three times a week for 25 days, followed by a 4-week wash-out period. IGF-I, IGFBP-3, the acid labile subunit (ALS), N-terminal propeptide of type I collagen (PINP), C-terminal telopeptide of type I collagen (ICTP) and N-terminal propeptide of type III collagen (PIIINP) were measured in samples collected at baseline (two samples), after 10, 22 and 24 days of r-HuEPO treatment and at the end of the 4-week wash-out period. Results, Treatment with r-HuEPO resulted in approximately threefold elevation of serum EPO and marked elevation of markers of erythropoiesis. There was no significant treatment effect of r-HuEPO compared to baseline on IGF-I, IGFBP-3, ALS, PINP, ICTP or PIIINP. Conclusions, r-HuEPO administration did not change markers of the IGF-system and of collagen turnover in young healthy male athletes. Therefore, use of r-HuEPO in athletes should not affect the validity of a GH doping test using these GH-responsive markers. [source] SDS-PAGE of recombinant and endogenous erythropoietins: benefits and limitations of the method for application in doping controlDRUG TESTING AND ANALYSIS, Issue 1 2009Christian Reichel Abstract Doping of athletes with recombinant and genetically modified erythropoietins (EPO) is currently detected by isoelectric focusing (IEF). The application of these drugs leads to a significant change in the isoform profile of endogenous urinary erythropoietin (uhEPO). Dynepo, MIRCERA, biosimilars with variable IEF-profiles as well as active urines and effort urines have made additional testing strategies necessary. The new generation of small molecule EPO-receptor stimulating agents like Hematide will also challenge the analytical concept of detecting the abuse of erythropoiesis stimulating agents (ESA). By determining their apparent molecular masses with SDS-PAGE a clear differentiation between endogenous and exogenous substances also concerning new EPO modifications is possible. Due to the orthogonal character of IEF- and SDS-PAGE both methods complement each other. The additional benefits of SDS-PAGE especially in relation to active and effort urines as well as the detection of Dynepo were investigated. Due to significant differences between the apparent molecular masses of uhEPO/serum EPO (shEPO) and recombinant, genetically or chemically modified erythropoietins the presence of active or effort urines was easily revealed. The characteristic band shape and apparent molecular mass of Dynepo on SDS-PAGE additionally evidenced the presence of this substance in urine. A protocol for the detection of EPO-doping in serum and plasma by SDS-PAGE was developed. Blood appears to be the ideal matrix for detecting all forms ESA-doping in the future. Copyright © 2009 John Wiley & Sons, Ltd. [source] | ||||||||||