
Françoise LasneAgence française de lutte contre le dopage | AFLD
Françoise Lasne
About
65
Publications
13,974
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
2,461
Citations
Citations since 2017
Publications
Publications (65)
Mont Blanc, the summit of Western Europe, is a popular but demanding high-altitude ascent. Drug use is thought to be widespread among climbers attempting this summit, not only to prevent altitude illnesses, but also to boost physical and/or psychological capacities. This practice may be unsafe in this remote alpine environment. However, robust data...
Description of Analytical Procedures.
(DOC)
Individual data of drug concentrations in urine samples from Mont Blanc climbers.
(DOCX)
Nonpolar anabolic steroids are doping agents that typically do not provide strong signals by electrospray ionization-mass spectrometry (ESI-MS) owing especially to the low polarity of the functional groups present. We have investigated the addition of anions, in ammonium salt form, to anabolic steroid samples as ionization enhancers and have confir...
Chlorazanil (Ordipan, N-(4-chlorophenyl)-1,3,5-triazine-2,4-diamine) is a diuretic agent and as such prohibited in sport according to the regulations of the World Anti-Doping Agency (WADA). Despite its introduction into clinical practice in the late 1950s, the worldwide very first two adverse analytical findings were registered only in 2014, being...
Glucocorticoids are among the most commonly used drugs. They are widely administered for acute and chronic musculoskeletal pain, as well as for several other pain syndromes, although their therapeutic use is sometimes diverted for doping purposes. Their time-course effects on hormonal and inflammatory responses nevertheless remain poorly understood...
The impact of oral contraceptives (OCs) on the saliva diurnal pattern of metabolic steroid hormones remained unknown.
Saliva samples were taken from young healthy women (11 OC users, 10 non-OC users) to analyze cortisol, dehydroepiandrosterone (DHEA) and testosterone 4 times (days 1, 8, 15 and 22) over one menstrual cycle.
OC use decreased saliva t...
As a synthetic analogue of adrenocorticotropic hormone (ACTH), tetracosactide is prohibited in sport by the World Anti-Doping Agency (WADA). An enzyme-linked immunosorbent assay (ELISA) method is proposed for detection of this drug in plasma. Since its structure corresponds to the 24 N-terminal of the 39 amino acids of the natural endogenous peptid...
The dehydroepiandrosterone (DHEA) and dehydroepiandrosterone sulfate (DHEA-S) concentrations during acute and chronic exercise (training) have been investigated only fairly recently. DHEA is generally preferred to DHEA-S for exploring the acute exercise repercussions in laboratory or field tests because of its shorter elimination half-life. Convers...
Significant alteration in hypothalamic-pituitary-adrenal function has been demonstrated in patients after short-term glucocorticoid therapy, but its impact on the circadian rhythm of steroid hormones has never been investigated. This study examined the effects of short-term prednisone administration on the diurnal patterns of dehydroepiandrosterone...
Objectif
Le but de cette étude était de déterminer les effets de l’obésité sur le rythme circadien de testostérone et de déhydroépiandrostérone chez des hommes obèses d’âge moyen.
Méthodes
Des échantillons salivaires ont été collectés au réveil et toutes les trois heures de neuf heures à 21 heures sur deux jours consécutifs chez huit hommes obèses...
Competitive swimmers regularly perform apnea series with or without fins as part of their training, but the ergogenic and metabolic repercussions of acute and chronic apnea have not been examined. Therefore, we aimed to investigate the cardiovascular, lactate, arterial oxygen saturation and hormonal responses to acute apnea in relation to performan...
Metabonomics has become a very valuable tool and many research fields rely on results coming out from this combination of analytical techniques, chemometric strategies, and biological interpretation. Moreover, the matrices are more and more complex and the implications of the results are often of major importance. In this context, the need for pert...
Luteinizing hormone (LH) is physiologically produced by the anterior pituitary gland. Male athletes may use pharmaceutical LH for doping since it increases the production of testosterone by testes. This hormone is thus on the World Anti-Doping Agency (WADA) list of substances prohibited for males. Anti-doping laboratories perform the assay of this...
The purpose of this study was to assess changes in the steroid hormone levels of elite athletes during an international powerlifting competition. Baseline cortisol, DHEA and testosterone were determined in saliva samples in 19 (8 men, 11 women) junior and sub-junior athletes on the day before competition, and then on the competition day during the...
Stimulation of erythropoiesis is one of the most efficient ways of doping. This type of doping is advantageous for aerobic physical exercise and of particular interest to endurance athletes. Erythropoiesis, which takes place in bone marrow, is under the control of EPO, a hormone secreted primarily by the kidneys when the arterial oxygen tension dec...
Diurnal patterns of cortisol and dehydroepiandrosterone (DHEA) secretion, the two main peripheral secretory products of the hypothalamic-pituitary-adrenal neuroendocrine stress axis, have been well characterized in rest conditions but not in relation to physical exercise. The purpose of this investigation was therefore to determine the effects of a...
We report here observations clearly demonstrating that gloves can have a deleterious impact on an IEF experiment. These observations were made during the practice of analyses for anti-doping control of erythropoietin. We show that the wearing of nitrile gloves to apply the catholyte strip onto the IEF gel may be responsible for dramatic distortions...
The aim of the study was to evaluate the effects of short-term glucocorticoid treatment on plasma amino acids, free fatty acids, blood glucose, and several hormones in healthy volunteers performing long-lasting exercise. 9 young female subjects exercised 2 h at 50-55% VO₂ max twice, once after placebo (Pla) ingestion and once after prednisone (Cor,...
Tetracosactide (Synacthen), a synthetic analogue of adrenocorticotropic hormone (ACTH), can be used as a doping agent to increase the secretion of glucocorticoids by adrenal glands. The only published method for anti-doping control of this drug in plasma relies on purification by immunoaffinity chromatography and LC/MS/MS analysis. Its limit of det...
This study examined the relationships between plasma and saliva adrenocortical hormones in response to long-duration submaximal exercise. In nine healthy, physically active, female volunteers, blood and saliva samples were taken at rest and every 30 min during a 120-min cycling trial at 50-55% VO(2max) for cortisol and dehydroepiandrosterone (DHEA)...
Isoelectric focusing is the basis of anti-doping control of recombinant erythropoietin in urine. A convenient preparative method is proposed for screening of Continuous Erythropoietin Receptor Activator (CERA) and Darbepoetin alfa in serum or plasma. This method makes isoelectric focusing as easy to use in blood as in urine. In comparison with urin...
Recombinant erythropoietin has a strong impact on aerobic power and is therefore one of the most potent doping agents in endurance sports. The anti-doping control of this synthetic hormone relies on the detection, in the urine, of its isoelectric pattern, which differs from that of the corresponding natural hormone, the latter being typically more...
Anti-doping control of erythropoietin (Epo) relies on the differentiation by isoelectric profile of natural endogenous hormone from the recombinant hormone used for doping. The first and second generations of recombinant Epo were detectable in urine.[1][1],[2][2] The third generation, Continuous
Ex vivo gene therapy is an interesting alternative to orthotopic liver transplantation (OLT) for treating metabolic liver diseases. In this study, we investigated its efficacy and biosafety in nonhuman primates. Hepatocytes isolated from liver lobectomy were transduced in suspension with a bicistronic liver-specific lentiviral vector and immediatel...
Nonspecific interactions between blotted proteins and unrelated secondary antibodies generate false positives in immunoblotting techniques. Some procedures have been developed to reduce this adsorption but they may work in specific applications and be ineffective in other ones. "Double-blotting" has been developed to overcome this problem. It consi...
By adding a step of immunoaffinity to the method we had previously developed for analysing erythropoietin (EPO) in urine, we were able to study the isoelectric profiles of this hormone in human serum samples. This method was sensitive enough to investigate samples presenting physiological levels of this hormone. Comparison with the corresponding pr...
The detection in urine of recombinant human erythropoietin (rHuEPO), a hormone misused by endurance athletes as a doping agent, is based on the differentiation of its isoelectric pattern from that of the corresponding natural hormone. Different empirical criteria have been proposed for discriminating the images of the patterns but none of them have...
We present a two-dimensional electrophoresis (2DE) method for the detection of the drug, recombinant erythropoietin (rHuEPO) in urine and its separation from endogenous erythropoietin (HuEPO). This method involves a one-step acetonitrile precipitation of the proteins in urine, addition of an internal standard, two-dimensional gel electrophoresis (2...
Beullens et al report the “false-positive detection of recombinant human erythropoietin in urine following strenuous physical exercise.”[1][1](p4711) This report, based on observations conducted on urine from 1 single subject, relies in fact on serious errors of interpretation of poor-quality
Altitude training is popular among athletes to augment oxygen delivery capabilities to tissues and to improve physical performance. Hypoxia inducible factor-1 (HIF-1) controls the expression of several genes' encoding involved in physiological responses towards reduced oxygen availability, in particular by increasing serum erythropoietin (EPO). It...
This study appraised the veracity of claims that athletes can evade doping controls by injecting microdoses of recombinant human erythropoietin (rHuEPO), which rapidly disappear from the circulation. We confirmed that microdosing can reduce the window of detection to as little as 12-18 hours post-injection, suggesting that authorities must adopt ap...
The "living high-training low" model (Hi-Lo) may improve aerobic performance in athletes, and the main mechanism of this improvement is thought to be augmented erythropoiesis. A positive effect of Hi-Lo has been demonstrated previously by using altitudes of 2,000-3,000 m. Since the rate of erythropoiesis is altitude-dependent, we tested whether a h...
The activation of caspases represents a crucial turning point during a batch or a fed-batch culture of mammalian cells. It not only affects the quantity but also the quality of the recombinant glycoprotein produced. In this study, the activation of various caspases, the release of intracellular sialidase and the changes in sialylation pattern of a...
Adeno-associated viral gene therapy has shown promise for the treatment of inherited and acquired retinal disorders. In most applications, regulation of expression is a critical concern for both safety and efficacy. The purpose of our study was to evaluate the ability of the tetracycline-regulatable system to establish long-term transgene regulatio...
The “living high–training low” model (LHTL), i.e., training in normoxia but sleeping/living in hypoxia, is designed to improve the athletes performance. However, LHTL efficacy still remains controversial and also little is known about the duration of its potential benefit. This study tested whether LHTL enhances aerobic performance in athletes, and...
The efficiency of "living high, training low" (LHTL) remains controversial, despite its wide utilization. This study aimed to verify whether maximal and/or submaximal aerobic performance were modified by LHTL and whether these effects persist for 15 days after returning to normoxia. Last, we tried to elucidate whether the mechanisms involved were o...
A direct detection method for anti-doping control of recombinant human erythropoietin (rHuEPO) abuse in racehorses is proposed.
This method involves screening of plasma (or serum) by an enzyme-linked immunosorbent assay specific for human EPO and confirmation
in urine samples by characterization of the urinary EPO isoelectric profile. This method w...
Forthcoming "genetic doping" is predicted to be undetectable. In the case of recombinant human erythropoietin (rhEPO), a hormone used in endurance sports, it is being predicted that exogenous drug injections will be replaced by the transfer of the corresponding gene into some of the athlete's own cells. The hormone thus produced inside the organism...
Hemoglobin-based oxygen carriers (HBOCs) are being developed as potential substitutes for the oxygen-carrying functions of erythrocytes, but athletes may obtain and experiment with HBOCs as an illicit means of enhancing oxygen transport. An electrophoretic technique has been developed to screen for the presence of HBOCs in blood samples (Lasne et a...
Hemoglobin-based oxygen carriers (HBOCs) have recently been included in the International Olympic Committee and World Anti-Doping Agency lists of substances and methods prohibited in sports. To enforce this rule and deter abuse of HBOCs in elite sports, it is necessary to develop HBOC-specific screening and confirmation tests that are the usual ste...
Erythropoietin (EPO) is normally present in urine at a low concentration (about 1IU/L, i.e., about 10ng/L) for a total protein concentration of at least 50mg/L. A method to study the isoelectric profile of this hormone from 20-ml urine aliquots without previous purification was developed. This method involves isoelectric focusing of the retentate f...
"Double-blotting" (DB) was developed to overcome the problem of non-specific binding of secondary antibodies in immunoblotting (IB). After it had been probed by the primary antibody, the membrane with the blotted proteins was assembled with a second blank membrane and submitted to a second blotting under acidic conditions. The primary antibody mole...
Human erythropoietin (Epo) is a 30,4 kDa glycoprotein. It is composed of 165 amino acids and 4 carbohydrate side chain. Tissue hypoxia is the main stimulus for epo synthesis. Epo maintains red cell production by inhibiting apoptosis of erythrocyte progenotors, and by stimulating their proliferation and differentiation into normoblasts. Since the en...
To assess the eventual effects of acute oral salbutamol intake on performance and metabolism during submaximal exercise, nine healthy volunteers completed two cycling trials at a power corresponding to 80-85% VO2max, after either placebo (Pla) or salbutamol (Sal, 6 mg) treatment, according to a double-blind randomized protocol. Blood samples were c...
The present study examined whether oral short-term administration of salbutamol (Sal) modifies performance and selected hormonal and metabolic variables during submaximal exercise. Eight recreational male athletes completed two cycling trials at 80-85% peak O(2) consumption until exhaustion after either gelatin placebo (Pla) or oral Sal (12 mg/day...
Erythropoietin is a hormone that stimulates the production of new red
blood cells (erythropoiesis). Although athletes use recombinant human
erythropoietin illicitly to boost the delivery of oxygen to the tissues
and enhance their performance in endurance sports, this widespread
doping practice cannot be controlled in the absence of a reliable
analy...
Introduction
This study was aimed at assessing changes in urinary free cortisol concentrations due to sport practising.
Methods
Urinary samples were taken from 103 national level athletes practising sports such as golf, shooting, weightlifting, soccer, rugby, tennis, cross, marathon, 1 hour after the end of the sporting event.
Results
Urinary fre...
Infection is the greatest problem in burn patients and topical antiseptics must be chosen with great care especially when cultured skin is grafted. We examined the cytotoxicity of 6 antiseptics commonly used on cultured human fibroblasts and keratinocytes. Cultured cells were exposed for 15 min to Hibitane (chlorhexidine), Biseptine (chlorhexidine...
Infection is the greatest problem in burn patients and topical antimicrobial agents must be chosen with great care, especially when cultured skin is grafted. We examined the cytotoxic effect of six antiseptics and six antibiotics commonly used on cultured human fibroblasts and keratinocytes. Cultured cells were exposed for 15 min to Hibitane® (chlo...
Radioimmunofixation of human ferritin following isoelectric focusing of serum was developed to study the microheterogeneity of this protein in native serum without previous purification or concentration. This method requires only 2-10 microliter of serum and can be used with levels of ferritin as low as 10 micrograms/l. In this way, the extensive m...
A sensitive staining method was developed for detecting proteins in agarose gels after isoelectric focusing. Its sensitivity is about 20 times that of the Coomassie blue R-250 staining technique, and the time required is only 10 min.
Collagenolytic enzyme release in alveolar structures is probably one of the initial events leading to impaired balance between collagen synthesis and degradation in the connective matrix of the lung, resulting in pulmonary fibrosis. The collagenolytic activity was determined in the bronchoalveolar fluid of 40 normal subjects or patients with miscel...
A new technique combining a neuraminidase treatment of thyroxine-binding globulin after serum isoelectric focusing and a second-dimensional isoelectric focusing was developed to study the role of sialic acid in the microheterogeneity of native thyroxine-binding globulin. By showing the change of PI occasioned by the desialylation for each of the ba...
A new technique of radioprint immunofixation following isoelectric focusing was applied to the study of microheterogeneity of thyroxine-binding globulin without purification, in individual sera; this protein appeared to give rise to at least seven bands with isoelectric points in the range of pI 4.2--5.0. Furthermore, two different distributions of...