La Hormona de crecimiento en el ámbito deportivo : métodos de detección, comparación y funcionamiento metodológico

This doctoral thesis describes the evaluation of analytical methodologies to detect human growth hormone (hGH) abuse in sport. Two main strategies are studied and compared. The first (direct method) measures changes in the proportions of hGH variants, expressed as ratios, which are altered after hGH administration. Two versions of the direct method are compared; one using ratios between recombinant and pituitary variants and a second using ratios between only 22 and 20 kDa hGH variants. To fully understand the immunoassays readings, all relevant antibodies were characterised by surface plasmon resonance (SPR). A second strategy (indirect method) measures changes in proteins, other than hGH, provoked by the use of hGH. These bio-markers should have a longer retrospective analytical power. To evaluate the performance of both strategies, two clinical trials with recombinant hGH (rhGH) were carried out with healthy male subjects. The resulting data have been compared and statistically assessed. It is the first time that all available strategies have been applied on a single data set and this allows better understanding of the analytical readings which provides an additional tool in the evaluation of anti-doping analyses.Esta tesis doctoral describe la evaluación de métodos analíticos para detectar el abuso de hormona de crecimiento humana (hGH) en el deporte. Se han estudiado y comparado dos estrategias. La primera o método directo mide cambios en la proporción de variantes de hGH expresados como ratios, que están alterados después de administrar hGH. Dos versiones del método directo son comparadas; una con ratios entre variantes recombinante e hipofisaria y otra con ratios entre variantes de 22 y de 20 kDa. Para una mejor comprensión, los anticuerpos relevantes utilizados en los inmunoensayos, se caracterizaron por medio de resonancia del plasmon de superficie (SPR). Una segunda estrategia o método indirecto mide cambios en bio-marcadores (proteínas) causados por uso de hGH recombinante (rhGH). Estos bio-marcadores presentan un poder analítico más fuerte y de mejor retrospección en el tiempo. Para evaluar el rendimiento de ambas estrategias se han realizado dos ensayos clínicos con rhGH en varones sanos. Los datos resultantes se han comparado y evaluado estadísticamente. Es la primera vez que ambas estrategias se han aplicado sobre una misma serie de datos y ello permite una mayor comprensión de lecturas analíticas lo que proporciona herramientas adicionales en la evaluación de los análisis anti-dopaje

Determination of recent growth hormone abuse using a single dried blood spot

BACKGROUND: Although it is being increasingly applied, blood collection for drug testing in sport presents some logistic issues that complicate full applicability on a large scale. The use of dried blood spots (DBS) could benefit compliant blood testing considerably owing to its simplicity, minimal invasiveness, analyte stability, and reduced costs. The aim of this study was to evaluate the applicability of DBS to the methodology approved by the World Anti-Doping Agency (WADA) for detection of doping by recombinant human growth hormone (rhGH) in serum. METHODS: A protocol for a single DBS analysis using the hGH isoforms differential immunoassays (kit 1 and kit 2) was developed and validated. A clinical study with healthy volunteers injected for 3 consecutive days with a low subcutaneous dose (0.027 mg · kg(-1) · day(-1) · person(-1)) of rhGH was conducted. Finger prick DBS and paired-time serum samples from arm venipuncture were compared. RESULTS: The analysis of the DBS-based protocol indicated that with only a single blood spot it was possible to detect positivity for growth hormone abuse. In spite of the low rhGH dose administered and independently of the kit used, the window of detection for DBS was confirmed in all analyzed samples up to 8 h after rhGH administration and extended up to 12 h in 50% of the cases. Serum positivity was detected in all studied samples for 12 h after administration. CONCLUSIONS: These results support the usefulness of DBS as a biological matrix for testing recent growth hormone abuse.Funding: Spanish Ministerio de Economia y Competitividad (MINECO) (DEP2012-32048), International Olympic Committee (IOC)-2014 IOC Anti-Doping Research Fund, and Italian Istituto Superiore di Sanit

Determination of recent growth hormone abuse using a single dried blood spot

BACKGROUND: Although it is being increasingly applied, blood collection for drug testing in sport presents some logistic issues that complicate full applicability on a large scale. The use of dried blood spots (DBS) could benefit compliant blood testing considerably owing to its simplicity, minimal invasiveness, analyte stability, and reduced costs. The aim of this study was to evaluate the applicability of DBS to the methodology approved by the World Anti-Doping Agency (WADA) for detection of doping by recombinant human growth hormone (rhGH) in serum. METHODS: A protocol for a single DBS analysis using the hGH isoforms differential immunoassays (kit 1 and kit 2) was developed and validated. A clinical study with healthy volunteers injected for 3 consecutive days with a low subcutaneous dose (0.027 mg · kg(-1) · day(-1) · person(-1)) of rhGH was conducted. Finger prick DBS and paired-time serum samples from arm venipuncture were compared. RESULTS: The analysis of the DBS-based protocol indicated that with only a single blood spot it was possible to detect positivity for growth hormone abuse. In spite of the low rhGH dose administered and independently of the kit used, the window of detection for DBS was confirmed in all analyzed samples up to 8 h after rhGH administration and extended up to 12 h in 50% of the cases. Serum positivity was detected in all studied samples for 12 h after administration. CONCLUSIONS: These results support the usefulness of DBS as a biological matrix for testing recent growth hormone abuse.Funding: Spanish Ministerio de Economia y Competitividad (MINECO) (DEP2012-32048), International Olympic Committee (IOC)-2014 IOC Anti-Doping Research Fund, and Italian Istituto Superiore di Sanit

The prognostic Role of hepatic venous pressure gradient in cirrhotic patients undergoing elective extrahepatic surgery

Background & aims: Surgery in cirrhosis is associated with a high morbidity and mortality. Retrospectively reported prognostic factors include emergency procedures, liver function (MELD/Child-Pugh scores) and portal hypertension (assessed by indirect markers). This study assessed the prognostic role of hepatic venous pressure gradient (HVPG) and other variables in elective extrahepatic surgery in patients with cirrhosis. Methods: A total of 140 patients with cirrhosis (Child-Pugh A/B/C: 59/37/4%), who were due to have elective extrahepatic surgery (121 abdominal; 9 cardiovascular/thoracic; 10 orthopedic and others), were prospectively included in 4 centers (2002-2011). Hepatic and systemic hemodynamics (HVPG, indocyanine green clearance, pulmonary artery catheterization) were assessed prior to surgery, and clinical and laboratory data were collected. Patients were followed-up for 1 year and mortality, transplantation, morbidity and post-surgical decompensation were studied. Results: Ninety-day and 1-year mortality rates were 8% and 17%, respectively. Variables independently associated with 1-year mortality were ASA class (American Society of Anesthesiologists), high-risk surgery (defined as open abdominal and cardiovascular/thoracic) and HVPG. These variables closely predicted 90-, 180- and 365-day mortality (C-statistic >0.8). HVPG values >16 mmHg were independently associated with mortality and values ≥20 mmHg identified a subgroup at very high risk of death (44%). Twenty-four patients presented persistent or de novo decompensation at 3 months. Low body mass index, Child-Pugh class and high-risk surgery were associated with death or decompensation. No patient with HVPG 0.63 developed decompensation. Conclusions: ASA class, HVPG and high-risk surgery were prognostic factors of 1-year mortality in cirrhotic patients undergoing elective extrahepatic surgery. HVPG values >16 mmHg, especially ≥20 mmHg, were associated with a high risk of post-surgical mortality.Supported in part by grants from Ministerio de Educacion yCiencia (SAF-2016-75767-R), and from Instituto de Salud CarlosIII (PIE 15/00027). CIBERehd is funded by Instituto de Salud Car-los III. ER was recipient of a Río Hortega award (2012–2014),Instituto de Salud Carlos III