117 research outputs found

    Traumatismes fermés du pancréas chez l'enfant : approche diagnostique et traitement non-opératoire

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    Moins de 0,5% à 12% des enfants avec un traumatisme abdominal développent une atteinte pancréatique.(1-5) Ces lésions pancréatiques résultent majoritairement de traumatismes abdominaux fermés.(1) Du fait de la nature corrosive des sécrétions pancréatiques, la guérison du pancréas est difficile. Il est donc important de poser rapidement le bon diagnostic et d'instaurer une prise en charge efficace. Cependant, diagnostiquer une atteinte pancréatique n'est pas toujours évident(6-8) au vu de la faible incidence de ces traumas et de la sémiologie non spécifique associée. La prise en charge thérapeutique reste actuellement controversée, surtout dans les cas les plus graves : faut-il opérer ou opter pour une prise en charge non-opératoire?(1,9) Le Centre Hospitalier Universitaire Vaudois (CHUV) est l'un des centres de référence suisses de chirurgie pédiatrique. Depuis la fin des années 1990, tous les cas de traumatismes pancréatiques pédiatriques, sauf un, y ont été pris en charge de manière non- opératoire. Cette prise en charge conservatrice a été effectuée indépendamment du degré de sévérité du trauma. Le but de cette étude est donc de rapporter et d'analyser les modalités de l'approche diagnostique et de traitement non-opératoire, qui sont appliquées dans cet hôpital depuis 1999

    Detection of testosterone administration based on the carbon isotope ratio profiling of endogenous steroids: international reference populations of professional soccer players

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    BACKGROUND AND OBJECTIVES: The determination of the carbon isotope ratio in androgen metabolites has been previously shown to be a reliable, direct method to detect testosterone misuse in the context of antidoping testing. Here, the variability in the 13C/12C ratios in urinary steroids in a widely heterogeneous cohort of professional soccer players residing in different countries (Argentina, Italy, Japan, South Africa, Switzerland and Uganda) is examined. METHODS: Carbon isotope ratios of selected androgens in urine specimens were determined using gas chromatography/combustion/isotope ratio mass spectrometry (GC-C-IRMS). RESULTS: Urinary steroids in Italian and Swiss populations were found to be enriched in 13C relative to other groups, reflecting higher consumption of C3 plants in these two countries. Importantly, detection criteria based on the difference in the carbon isotope ratio of androsterone and pregnanediol for each population were found to be well below the established threshold value for positive cases. CONCLUSIONS: The results obtained with the tested diet groups highlight the importance of adapting the criteria if one wishes to increase the sensitivity of exogenous testosterone detection. In addition, confirmatory tests might be rendered more efficient by combining isotope ratio mass spectrometry with refined interpretation criteria for positivity and subject-based profiling of steroids

    Forensic identification of urine samples: a comparison between nuclear and mitochondrial DNA markers

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    Urine samples from 20 male volunteers of European Caucasian origin were stored at 4°C over a 4-month period in order to compare the identification potential of nuclear DNA (nDNA) and mitochondrial DNA (mtDNA) markers. The amount of nDNA recovered from urines dramatically declined over time. Consequently, nDNA likelihood ratios (LRs) greater than 1,000 were obtained for 100, 70 and 55% of the urines analysed after 6, 60 and 120 days, respectively. For the mtDNA, HVI and HVII sequences were obtained for all samples tested, whatever the period considered. Nevertheless, the highest mtDNA LR of 435 was relatively low compared to its nDNA equivalent. Indeed, LRs obtained with only three nDNA loci could easily exceed this value and are quite easier to obtain. Overall, the joint use of nDNA and mtDNA markers enabled the 20 urine samples to be identified, even after the 4-month perio

    Steroid profiling by UHPLC-MS/MS in dried blood spots collected from healthy women with and without testosterone gel administration.

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    The quantification of a large panel of endogenous steroids in serum by LC-MS/MS represents a powerful clinical tool for the screening or diagnosis of diverse endocrine disorders. This approach has also demonstrated excellent sensitivity for the detection of testosterone misuse in the anti-doping field, especially in female athlete population. In both situations, the use of dried blood spots (DBS) could provide a viable alternative to invasive venous blood collection. Here, the evaluation of DBS sampling for the quantification of a panel of endogenous steroids using UHPLC-MS/MS is described. The UHPLC-MS/MS method was validated for quantitative analysis of eleven free and eight conjugated steroids and was then used for the analysis of DBS samples collected in 14 healthy women during a normal menstrual cycle (control phase) followed by a 28-days testosterone gel treatment (treatment phase). Results were compared with those obtained from serum matrix. Satisfactory performance was obtained for all compounds in terms of selectivity, linearity, accuracy, precision, combined uncertainty, stability as well as extraction recovery and matrix effects. In control phase, high correlation was observed between DBS and serum concentrations for most compounds. In treatment phase, higher testosterone concentrations were observed in capillary than in venous DBS, suggesting a possible interference resulting from testosterone contamination on finger(s) used for gel application. Steroid profiling in capillary DBS represents a simple and efficient strategy for monitoring endogenous steroid concentrations and their fluctuation in clinical context of steroid-related disorders, or for the detection of testosterone abuse in anti-doping

    Urinary analysis of four testosterone metabolites and pregnanediol by gas chromatography-combustion-isotope ratio mass spectrometry after oral administrations of testosterone.

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    The most frequently used method to demonstrate testosterone abuse is the determination of the testosterone and epitestosterone concentration ratio (T/E ratio) in urine. Nevertheless, it is known that factors other than testosterone administration may increase the T/E ratio. In the last years, the determination of the carbon isotope ratio has proven to be the most promising method to help discriminate between naturally elevated T/E ratios and those reflecting T use. In this paper, an excretion study following oral administration of 40 mg testosterone undecanoate initially and 13 h later is presented. Four testosterone metabolites (androsterone, etiocholanolone, 5 alpha-androstanediol, and 5 beta-androstanediol) together with an endogenous reference (5 beta-pregnanediol) were extracted from the urines and the delta(13)C/(12)C ratio of each compound was analyzed by gas chromatography-combustion-isotope ratio mass spectrometry. The results show similar maximum delta(13)C-value variations (parts per thousand difference of delta(13)C/(12)C ratio from the isotope ratio standard) for the T metabolites and concomitant changes of the T/E ratios after administration of the first and the second dose of T. Whereas the T/E ratios as well as the androsterone, etiocholanolone and 5 alpha-androstanediol delta(13)C-values returned to the baseline 15 h after the second T administration, a decrease of the 5 beta-androstanediol delta-values could be detected for over 40 h. This suggests that measurements of 5 beta-androstanediol delta-values allow the detection of a testosterone ingestion over a longer post-administration period than other T metabolites delta(13)C-values or than the usual T/E ratio approach

    Detection of exogenous GHB in blood by gas chromatography-combustion-isotope ratio mass spectrometry: implications in postmortem toxicology.

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    Because GHB (gamma-hydroxybutyrate) is present in both blood and urine of the general population, toxicologists must be able to discriminate between endogenous levels and a concentration resulting from exposure. In this paper, we propose a procedure for the detection of exogenous GHB in blood by gas chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS). Following liquid-liquid and solid-phase extractions, GHB is derivatized to GHB di-TMS before analysis by GC-C-IRMS. Significant differences in the carbon isotopic ratio (delta(13)C-values > 13.5 per thousand) were found between endogenous and synthetic GHB. Indeed, for postmortem blood samples with different GHB concentrations (range: 13.8-86.3 mg/L), we have obtained GHB delta(13)C-values ranging from -20.6 to -24.7 per thousand, whereas delta(13)C-values for the GHB from police seizure were in the range -38.2 to -50.2 per thousand. In contrast to the use of cut-off concentrations for positive postmortem blood GHB concentrations, this method should provide an unambiguous indication of the drug origin

    Combination of carbon isotope ratio with hydrogen isotope ratio determinations in sports drug testing.

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    Carbon isotope ratio (CIR) analysis has been routinely and successfully applied to doping control analysis for many years to uncover the misuse of endogenous steroids such as testosterone. Over the years, several challenges and limitations of this approach became apparent, e.g., the influence of inadequate chromatographic separation on CIR values or the emergence of steroid preparations comprising identical CIRs as endogenous steroids. While the latter has been addressed recently by the implementation of hydrogen isotope ratios (HIR), an improved sample preparation for CIR avoiding co-eluting compounds is presented herein together with newly established reference values of those endogenous steroids being relevant for doping controls. From the fraction of glucuronidated steroids 5β-pregnane-3α,20α-diol, 5α-androst-16-en-3α-ol, 3α-Hydroxy-5β-androstane-11,17-dione, 3α-hydroxy-5α-androstan-17-one (ANDRO), 3α-hydroxy-5β-androstan-17-one (ETIO), 3β-hydroxy-androst-5-en-17-one (DHEA), 5α- and 5β-androstane-3α,17β-diol (5aDIOL and 5bDIOL), 17β-hydroxy-androst-4-en-3-one and 17α-hydroxy-androst-4-en-3-one were included. In addition, sulfate conjugates of ANDRO, ETIO, DHEA, 3β-hydroxy-5α-androstan-17-one plus 17α- and androst-5-ene-3β,17β-diol were considered and analyzed after acidic solvolysis. The results obtained for the reference population encompassing n = 67 males and females confirmed earlier findings regarding factors influencing endogenous CIR. Variations in sample preparation influenced CIR measurements especially for 5aDIOL and 5bDIOL, the most valuable steroidal analytes for the detection of testosterone misuse. Earlier investigations on the HIR of the same reference population enabled the evaluation of combined measurements of CIR and HIR and its usefulness regarding both steroid metabolism studies and doping control analysis. The combination of both stable isotopes would allow for lower reference limits providing the same statistical power and certainty to distinguish between the endo- or exogenous origin of a urinary steroid

    Antidoping programme and biological monitoring before and during the 2014 FIFA World Cup Brazil.

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    BACKGROUND: The FIFA has implemented an important antidoping programme for the 2014 FIFA World Cup. AIM: To perform the analyses before and during the World Cup with biological monitoring of blood and urine samples. METHODS: All qualified players from the 32 teams participating in the World Cup were tested out-of-competition. During the World Cup, 2-8 players per match were tested. Over 1000 samples were collected in total and analysed in the WADA accredited Laboratory of Lausanne. RESULTS: The quality of the analyses was at the required level as described in the WADA technical documents. The urinary steroid profiles of the players were stable and consistent with previously published papers on football players. During the competition, amphetamine was detected in a sample collected on a player who had a therapeutic use exemption for attention deficit hyperactivity disorder. The blood passport data showed no significant difference in haemoglobin values between out-of-competition and postmatch samples. CONCLUSIONS: Logistical issues linked to biological samples collection, and the overseas shipment during the World Cup did not impair the quality of the analyses, especially when used as the biological passport of football players
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