University faculty on student motivation to use medical education apps and barriers to their usage.

OBJECTIVE: University teachers, who primarily provide guidance and advice to their students, can play a significant role in educational process transformation. As there is no particular e-learning framework, it is important to understand the factors and variables that may impact both its effective usage and further successful implementation. The current study aims to outline the influence of university faculty, and possible barriers preventing medical students from using apps for learning purposes. SUBJECTS AND METHODS: Α cross-sectional study was conducted with an online survey questionnaire. The population of the study included 1,458 students from all the seven Greek schools of medicine. RESULTS: University faculty (51.7%), followed by fellow students and friends (55.6%), constitute the second most common source of information on adopting apps for medical education. 45.8% of students rated their educational guidance as insufficient/inadequate, 33.0% as moderate, 18.6% as quite good, and only 2.7% as sufficient/complete. University professors have proposed certain apps to 25.5% of students. PubMed (41.7%), Medscape (20.9%), and Complete Anatomy (12.2%) were the leading suggestions. The main barriers to app usage were the lack of knowledge of apps' benefits (28.8%), insufficient updates of their content (21.9%), their cost-effectiveness (19.2%), and financial reasons (16.2%). Most students preferred using free apps (51.4%) and 76.7% preferred universities to cover apps' expenses. CONCLUSIONS: University faculty represent the main source of information regarding the adaptation of medical apps in the educational process. However, students need improved and enhanced guidance. The main barriers are ignorance about apps and financial reasons. The majority prefer free apps and universities to cover their cost.

Medical application usage traits by students in Greece.

OBJECTIVE: Medical applications ("apps") can offer innovative educational capabilities, facilitating the acquisition of learning objectives and enhancing decision making. The present study aims at demonstrating the usage characteristics and relevant perceptions among students in seven medical schools in Greece. MATERIALS AND METHODS: A descriptive cross-sectional study was conducted through an online survey. Popularity, usage patterns and medical student perceptions regarding medical apps were studied. RESULTS: A total of 1,458 undergraduate medical students participated, 99.2% owned a smartphone, 72.8% were aware of medical apps' existence, although only 53.9% used them. Apps awareness was higher in higher-ranked universities. Overall, 46% used 1-3 apps, 7.9% more than four apps. 40.3% stated apps' usage at least 1-3 times a month, followed by 16.0% using them 1-3 times per week. Only 2.5% reported daily usage. Students who used more apps tend to use them more frequently. 77.3% used at least half of the downloaded apps. Awareness of medical apps, number of apps in use and frequency of usage tend to increase in each succeeding year of study. The most popular apps and the main reasons of usage are presented in this study. Current and future perceptions have been investigated. No disparities have been observed between genders. CONCLUSIONS: Overall medical apps usage was relatively low, despite the high percentage of smartphone ownership. Quantitative traits are enhanced across the progression of medical studies. Utilization frequency is higher in those using more apps. Distinct utilization patterns were identified between preclinical and clinical students, possibly depicting particular needs, portraying apps as a special adjunctive educational tool.

Red blood cell derived extracellular vesicles during the process of autologous blood doping.

The purpose of this pilot study was to investigate the effects of the transfusion of one erythrocyte concentrate on the number of circulating red blood cell extracellular vesicles (RBC-EVs) and their clearance time. Six, healthy volunteers donated their blood and were transfused with their RBC concentrate after 35-36 days of storage. One K2 EDTA and one serum sample were collected before donation, at four timepoints after donation and at another six timepoints after transfusion. RBC-EVs were analyzed on a Cytek Aurora flow cytometer. A highly significant increase (p < 0.001) of RBC-EVs from an average of 60.1 ± 19.8 (103 /µL) at baseline to 179.3 ± 84.7 (103 /µL) in the first 1-3 h after transfusion could be observed. Individual differences in the response to transfusion became apparent with one volunteer showing no increase and another an increased concentration at one timepoint after donation due to an influenza infection. We concluded that in an individualized passport approach, increased RBC-EVs might be considered as additional evidence when interpreting suspicious Athletes Biological Passport (ABPs) but for this additional research related to sample collection and transport processes as well as method development and harmonization would be necessary.

Cardiotoxic Profile and Arterial Stiffness of Adjuvant Chemotherapy for Colorectal Cancer.

BACKGROUND AND PURPOSE: Even though new cancer therapies have improved the overall survival, in some cases they have been associated with adverse effects, including increased cardiotoxicity. The purpose of the present study was to assess the cardiovascular effects of adjuvant chemotherapy for colorectal cancer and mainly the impact on arterial stiffness indices. MATERIAL AND METHODS: A total of 70 patients with non-metastatic colorectal cancer who were treated either with FOLFOX (n=16) or with XELOX (n=54) adjuvant chemotherapy were included in the study. All patients were subjected to full cardiovascular evaluation at the beginning and the end of chemotherapy. Arterial stiffness was assessed by means of pulse wave velocity (PWV) and augmentation index (Aix) and full laboratory examinations were conducted prior to, and soon after, the termination of chemotherapy. RESULTS: Patients exhibited significantly higher levels of carotid-radial PWV, carotid femoral RWV and Aix post-chemotherapy (p<0.001); these findings remained significant when examined separately in each treatment subgroup (FOLFOX, XELOX). The observed changes were independent of treatment regimen and baseline patient characteristics. Univariate regression analyses showed that baseline PWVc-r and PWVc-f were the only factors associated with PWVc-r and PWVc-f change, while Aix change was independent of its baseline value. CONCLUSION: There is a clear burden in arterial stiffness indices post-adjuvant chemotherapy for colorectal cancer in both chemotherapy groups. This is a finding of important clinical significance, however more prospective studies are required in order to encode the possible mechanisms involved.

Visual and anatomic outcomes of aflibercept treatment in treatment-naive patients with neovascular age-related macular degeneration; real-life data over 24 months.

PURPOSE: The aim of this study is to evaluate the 2-year visual and anatomic results of treatment with intravitreal injections of aflibercept in newly diagnosed, treatment-naive patients with neovascular age-related macular degeneration in routine clinical practice of a tertiary hospital of Southwestern Greece. METHODS: In this retrospective, single-center, non-randomized case-series study we analyzed the records of 32 treatment-naive eyes of 28 patients treated with intravitreal injections of aflibercept. Patients received treatment in the Department of Ophthalmology of the University Hospital of Patras from January 2017 to August 2019. The scheduled treatment regimen included a loading dose of 3 consecutive monthly injections of aflibercept and then injections at 8-week intervals for the next 9 months followed by a treat and extend treatment during the second year. Data such as age, gender, best corrected visual acuity (BCVA) and number of injections were recorded. Spectral domain optical coherence tomography (SD-OCT) findings including presence or absence of fluid and automated central macular thickness measurement at baseline, 12 and 24 months were also recorded. RESULTS: The mean age of the patients (14 male, 14 female) was 78.5±7.73 years. Over a period of 12 months, and after a median number of 6 visits (range 3-10), patients received a median number of 6 intravitreal injections of aflibercept (range 3-8). Twenty eyes completed 2 years of treatment with aflibercept. Over the 2-year period patients conducted a median of 14 visits (range 9-15) and received a median number of 10 IVAs (range 6-13). The median logMAR BCVA at 12 months was significantly better compared to baseline [0.412 (range 0.046-1.097) versus 0.549 (range 0-1.301) respectively; p=0.003] while median logMAR BCVA at 24 months [0.398 (range 0.222-1.097)] did not differ significantly compared to baseline (p=0.295). The central macular thickness at baseline was 398.75±98.16 µm and decreased statistically significantly at 12 (295.81±80.48 µm) and 24 months (289.29±34.25 µm) compared to baseline (p=0.0002 and p=0.002, respectively). At baseline SD-OCT examination subretinal fluid (SRF) was present in 26 eyes (81.25%), intraretinal fluid (IRF) was present in 20 eyes (62.5%) while pigment epithelium detachment (PED) was observed in 28 eyes (87.5%) At 12 months SRF was present in 16 eyes (50%), IRF was present in 10 eyes (31.25%) while PED was observed in 23 eyes (71.88%). At 24 months examination SRF was present in 4 eyes (20%), IRF was present in 10 eyes (50%) while PED was observed in 14 eyes (70%). No serious adverse events occurred during this period. CONCLUSION: Treatment with intravitreal injections of aflibercept in a real life setting resulted in a significant improvement in BCVA at 12 months and in a significant anatomic restoration throughout the 24-month follow-up.

Functional and anatomic results of up to 24 months aflibercept treatment for diabetic macular edema in real-life setting.

PURPOSE: Treatment with intravitreal injections of anti-vascular endothelial growth factors, like aflibercept, has revolutionized the management of diabetic macular edema. The purpose of this study is to evaluate the 2-year results of treatment with aflibercept in newly diagnosed, treatment-naive patients with diabetic macular edema in a real-life setting in a tertiary hospital of Southwestern Greece. METHODS: In this retrospective, real-life, single-center, cohort study the records of diabetic patients were reviewed. In the study we included treatment naive eyes that started treatment with intravitreal injections of aflibercept in the Department of Ophthalmology of the University Hospital of Patras. The scheduled treatment regimen of aflibercept was based on the Summary of Product Characteristics of the product and included a loading dose of 5 monthly aflibercept injections followed by bimonthly treatment until the completion of the first year. During the second year a treat and extend treatment regimen was applied. We recorded data such as age, gender, number of visits and injections, best corrected visual acuity (BCVA) and central macular thickness (CMT) as it was evaluated by a spectral domain optical coherence tomography (SD-OCT). RESULTS: Thirty treatment-naive eyes of 22 patients (14 male, 8 female) received treatment with aflibercept for at least 1 year during the period between January 2017 and August 2019. The mean age of the patients was 68.64±7.35 years. Ninety percent of the patients suffered from type-II diabetes and 9% from type-I. The median time between the diagnosis of diabetic macular edema and initiation of treatment with intravitreal injections of aflibercept was 0.5 months (range 0-3 months). Median baseline logMAR BCVA was 0.398 (range 0.046-1.301). The mean CMT at baseline was 388.0±162.94µm. Over a period of 12 months, and after a mean number of 7.5±2.3 visits, patients received a mean number of 7±1.12 intravitreal injections of aflibercept. Eighteen eyes (60%) received an induction phase with 5 monthly injections according to aflibercept SPC. After 12 months the median BCVA (0.324, range 0.0-1.3) was statistically significantly better compared to baseline (p=0.024) and the CMT (295.67±70.99) was significantly lower compared to baseline (p=0.017). Eighteen eyes (60%) completed 2 years of treatment with aflibercept. Over the 2-year period patients made a mean number of 12.7±3.08 visits and received a mean number of 10.2±1.64 intravitreal injections of aflibercept. The median logMAR BCVA at 2 years (0.301, range 0-0.52) was statistically significantly better compared to baseline (p=0.013) and the CMT (293.53±65.93) was significantly lower compared to baseline (p=0.01). No serious adverse events were recorded during this period. CONCLUSION: Aflibercept resulted in significant functional and anatomic improvement after 12- and 24-month treatment in diabetic macular edema eyes in a real-life setting. The majority of the eyes completed the 2-year treatment regimen of aflibercept.

Evaluation of intraocular pressure in the first 24hours after micropulse laser trabeculoplasty in eyes with pseudoexfoliation glaucoma.

PURPOSE: To evaluate the immediate 24-hour effect on intraocular pressure (IOP) of a single session of micropulse laser trabeculoplasty (MLT) in patients with pseudoexfoliation glaucoma (PEXG). PATIENTS AND METHODS: In this single-center, one-arm, prospective study, patients with PEXG on prostaglandin analogue monotherapy with inadequate IOP control were treated with 360-degree 532nm MLT. Intraocular pressure was evaluated at 1, 4, 8, 12 and 24hours after MLT. Twenty-three eyes of eighteen patients (10 male, 8 female) were enrolled in the study. RESULTS: The mean age of the patients was 71.83±6.51 years, and the mean IOP prior to MLT was 20.61±1.8mmHg. The mean IOP was reduced by 2.17±3.31mmHg, 2.69±3.85mmHg, 0.87±3.02mmHg, 2.13±2.8mmHg and -0.87±3mmHg at 1, 4, 8 and 24hours after MLT, respectively. At 4 and 12hours after MLT, the mean IOP was statistically significantly lower compared to the pre-MLT IOP (P=0.043 and P=0.021 respectively). No eye experienced an IOP spike≥5mmHg during the first 24hours after MLT. CONCUSION: Treatment with MLT in PEXG eyes did not result in any significant, potentially dangerous IOP spikes during the first 24hours after MLT.

The effect of athletes` hyperhydration on the urinary 'steroid profile' markers in doping control analysis.

The urinary 'steroid profile' in doping control analysis is a powerful tool aimed at detecting intra-individual deviations related to the abuse of endogenous steroids. Factors altering the steroid profile include, among others, the excessive fluid intake leading to low endogenous steroids concentrations compared to an individual's normal values. Cases report the use of hyperhydration by athletes as a masking method during anti-doping urine sample collection. Seven healthy physically active non-smoking Caucasian males were examined for a 72-hour period using water and a commercial sports drink as hyperhydration agents (20 mL/kg body weight). Urine samples were collected and analyzed according to World Anti-Doping Agency (WADA) technical documents. Although, significant differences were observed on the endogenous steroid concentrations under the studied hyperhydration conditions, specific gravity adjustment based on a reference value of 1.020 can eliminate the dilution induced effect. Adjustment methods based on creatinine and urinary flow rate were also examined; however, specific gravity was the optimum method in terms of effectiveness to adjust concentrations close to the baseline steroid profile and practicability. No significant effect on the urinary steroid ratios was observed with variability values within 30% of the mean for the majority of data. Furthermore, no masking on the detection ability of endogenous steroids was observed due to hyperhydration. It can be concluded that any deviation on the endogenous steroid concentrations due to excessive fluid intake can be compensated by the specific gravity adjustment and therefore, hyperhydration is not effective as a masking method on the detection of the abuse of endogenous steroids.

Α molecular epidemiological analysis of adenoviruses from excess conjunctivitis cases.

BACKGROUND: Τo perform a molecular epidemiological analysis of viral conjunctivitis among excess conjunctivitis cases recorded at the University Hospital of Patras, Greece, for the period March to June 2012. METHODS: A structured questionnaire containing demographic and clinical data was developed in order to collect retrospective data on the cases. Eye swab specimens were collected and molecular detection of adenoviruses was performed by nested PCR. Positive results were confirmed by sequencing. To determine the relatedness between the isolated sequences, a phylogenetic analysis was conducted. RESULTS: The epidemiological analysis (including retrospective data) included 231 conjunctivitis cases (47.1% male, and 52.8% female). Based on clinical features 205 of the cases were diagnosed of viral origin (46.3% male and 53.7% female), 4 of bacterial origin (50% male and 50% female) while 22 were undefined conjunctivitis. The outbreak excess cases (included 156 cases) affected all age groups regardless gender predilection. For the positive samples indicated that 29 samples (72.5%) were AdV17, and 5 (12.5%) as AdV54. CONCLUSIONS: Molecular analysis could define the cause of viral conjunctivitis, while epidemiological data contributed to the assessment of the risk factors and underlined possible preventive measures. This study is one of the very few on viral conjunctivitis in Greece. This outbreak underscores the need for a national surveillance system for acute infectious conjunctivitis outbreaks. The epidemiological as well as molecular investigation on HAdV ocular infections is rather absent in Greece, which has no surveillance system for viral conjunctivitis.

Markers of mesterolone abuse in sulfate fraction for doping control in human urine.

This manuscript describes the direct detection of mesteroloe sulfo-conjugated metabolites by liquid chromatography/quadrupole/time of flight mass spectrometry (LC/Q/TOFMS) with special focus on evaluation of their retrospective detectability and their structure elucidation. A comparison of their long-term detectability, with the mesterolone main metabolite (1α-methyl-5α-androstan-3α-ol-17-one) excreted in glucuronide fraction and detected by gas chromatography/high resolution mass spectrometry (GC/HRMS), is also presented. Studies on mesterolone were performed with samples obtained from two excretion studies after single oral administration of Proviron© by healthy volunteers. Potential sulfate metabolites were detected in post administration samples after liquid-liquid extraction (LLE) with ethyl acetate and LC/TOFMS analysis, in negative mode. Twelve mesterolone sulfate metabolites from the first excretion study and nine from the second were subsequently confirmed by LC/Q/TOFMS. Finally, six mesterolone sulfate metabolites were considered important taking into account their abundance and long-term detectability, encoded as M1, M2, M4, M5, M6 and M7. The proposed mesterolone sulfate metabolites M1, M2, M4 and M5 (excreted as sulfates) have the same retrospectivity with the main mesterolone metabolite, excreted in glucuronide fraction. For metabolite characterization, LC fractionation was performed. The metabolites were identified and characterized by GC/MS, after solvolysis and derivatization. Combined mass spectra data from trimethyl-silyl (TMS), TMS-enolTMS and methoxime-TMS derivatives were taken into account for the characterization of these metabolites. It was concluded that M1 is 1α-methyl-5α-androstan-3ß-ol-17 one, M2 is 1α-methyl-5α-androstan-3α-ol-17 one, M4 is 1α-methyl-5a-androstan-3ß, 16z-diol-17-one, M5 is 1α-methyl-5α-androstan-17z,4ξ-diol-3one, M6 is 1α-methyl-5α-androstan-3z,6z-diol-17-one and M7 is 4z-hydroxy-1α-methyl-5α-androstan-3,17-dione.

The effect of fasting during Ramadan on parameters of the haematological and steroidal modules of the athletes biological passport - a pilot study.

This study investigated the effect of Ramadan on the haematological and steroid module of the Athletes Biological Passport (ABP) of the World Anti-Doping Agency (WADA). Nine healthy physically active subjects were tested in the morning and afternoon for two days before and three days during Ramadan. Sample collection and all analyses were performed according to WADA technical documents. Although there were significant changes in the haemoglobin concentration during Ramadan, especially during the first fasting week, none of the subjects in this study exceeded the individually calculated thresholds of the ABP. No significant effects on testosterone/epitestosterone (T/E) ratio were observed but only the afternoon specific gravity (SG) of the urine was elevated. Thus, when urinary steroid concentrations are required, SG corrections need to be performed. The haematological and the steroid module of the ABP can be reliably applied during Ramadan as the observed changes are only marginal.

Comparison of sulfo-conjugated and gluco-conjugated urinary metabolites for detection of methenolone misuse in doping control by LC-HRMS, GC-MS and GC-HRMS.

Methenolone (17ß-hydroxy-1-methyl-5α-androst-1-en-3-one) misuse in doping control is commonly detected by monitoring the parent molecule and its metabolite (1-methylene-5α-androstan-3α-ol-17-one) excreted conjugated with glucuronic acid using gas chromatography-mass spectrometry (GC-MS) and liquid chromatography mass spectrometry (LC-MS) for the parent molecule, after hydrolysis with ß-glucuronidase. The aim of the present study was the evaluation of the sulfate fraction of methenolone metabolism by LC-high resolution (HR)MS and the estimation of the long-term detectability of its sulfate metabolites analyzed by liquid chromatography tandem mass spectrometry (LC-HRMSMS) compared with the current practice for the detection of methenolone misuse used by the anti-doping laboratories. Methenolone was administered to two healthy male volunteers, and urine samples were collected up to 12 and 26 days, respectively. Ethyl acetate extraction at weak alkaline pH was performed and then the sulfate conjugates were analyzed by LC-HRMS using electrospray ionization in negative mode searching for [M-H](-) ions corresponding to potential sulfate structures (comprising structure alterations such as hydroxylations, oxidations, reductions and combinations of them). Eight sulfate metabolites were finally detected, but four of them were considered important as the most abundant and long term detectable. LC clean up followed by solvolysis and GC/MS analysis of trimethylsilylated (TMS) derivatives reveal that the sulfate analogs of methenolone as well as of 1-methylene-5α-androstan-3α-ol-17-one, 3z-hydroxy-1ß-methyl-5α-androstan-17-one and 16ß-hydroxy-1-methyl-5α-androst-1-ene-3,17-dione were the major metabolites in the sulfate fraction. The results of the present study also document for the first time the methenolone sulfate as well as the 3z-hydroxy-1ß-methyl-5α-androstan-17-one sulfate as metabolites of methenolone in human urine. The time window for the detectability of methenolone sulfate metabolites by LC-HRMS is comparable with that of their hydrolyzed glucuronide analogs analyzed by GC-MS. The results of the study demonstrate the importance of sulfation as a phase II metabolic pathway for methenolone metabolism, proposing four metabolites as significant components of the sulfate fraction.

Sports doping: emerging designer and therapeutic ß2-agonists.

Beta2-adrenergic agonists, or ß2-agonists, are considered essential bronchodilator drugs in the treatment of bronchial asthma, both as symptom-relievers and, in combination with inhaled corticosteroids, as disease-controllers. The use of ß2-agonists is prohibited in sports by the World Anti-Doping Agency (WADA) due to claimed anabolic effects, and also, is prohibited as growth promoters in cattle fattening in the European Union. This paper reviews the last seven-year (2006-2012) literature concerning the development of novel ß2-agonists molecules either by modifying the molecule of known ß2-agonists or by introducing moieties producing indole-, adamantyl- or phenyl urea derivatives. New emerging ß2-agonists molecules for future therapeutic use are also presented, intending to emphasize their potential use for doping purposes or as growth promoters in the near future.

Comparison of multiple linear regression, partial least squares and artificial neural networks for prediction of gas chromatographic relative retention times of trimethylsilylated anabolic androgenic steroids.

The comparison among different modelling techniques, such as multiple linear regression, partial least squares and artificial neural networks, has been performed in order to construct and evaluate models for prediction of gas chromatographic relative retention times of trimethylsilylated anabolic androgenic steroids. The performance of the quantitative structure-retention relationship study, using the multiple linear regression and partial least squares techniques, has been previously conducted. In the present study, artificial neural networks models were constructed and used for the prediction of relative retention times of anabolic androgenic steroids, while their efficiency is compared with that of the models derived from the multiple linear regression and partial least squares techniques. For overall ranking of the models, a novel procedure [Trends Anal. Chem. 29 (2010) 101-109] based on sum of ranking differences was applied, which permits the best model to be selected. The suggested models are considered useful for the estimation of relative retention times of designer steroids for which no analytical data are available.

Two-step derivatization procedures for the ionization enhancement of anabolic steroids in LC-ESI-MS for doping control analysis.

BACKGROUND: Two-step derivatization procedures were developed for the enhancement of the positive ESI in LC-MS detection of anabolic androgenic steroids, a class of prohibited substances with limited ionization efficiency in atmospheric pressure interfaces. The developed procedures are based on the esterification of hydroxyl groups of anabolic steroids with picolinic acid, followed by conversion of carbonyl groups to Schiff bases by either Girard's reagent T or 2-hydrazino pyridin. RESULTS: Ionization efficiency for the model derivatized compounds 19-norandrosterone (nandrolone main metabolite) and methasterone was higher by almost two orders of magnitude compared with the respective efficiency of the underivatized compounds. CONCLUSION: The obtained derivatives provided a significant improvement in the ESI sensitivity, compared with those of underivatized molecules in positive LC-ESI-ion trap-MS full-scan mode.

Estimating measurement uncertainty in quantitative methods not based on chromatography for doping control purposes.

Estimation of measurement uncertainty (MU) for quantitative results is a requirement of ISO/IEC17025. This concept is well established for chromatographic methods in doping control and forensic analysis. For non-chromatographic methods, however, very few practical methodologies have been published. In this paper, the applicability of a top-down model, established for estimating uncertainty in chromatography, was evaluated for two other methodologies with different sets of raw data as a starting point. The first case study involves the estimation of MU for the determination of haematological parameters. In this case, a large data set of quality control material and proficiency testing results was available to establish MU. The second case study involves the estimation of MU for the recently approved method for the determination of human growth hormone misuse. In this case the amount of data available to establish MU was limited to results from method validation and a basic set of analysis data. In both cases a methodology based upon long-term bias, long-term imprecision and--eventually--a correction for standard impurity is proposed. The proposed methodology can be regarded as a dynamic procedure, which allows re-evaluation of MU on a regular basis. Finally, a concept for the verification and evaluation of MU estimations using proficiency testing results is proposed.

Preventive doping control screening analysis of prohibited substances in human urine using rapid-resolution liquid chromatography/high-resolution time-of-flight mass spectrometry.

Unification of the screening protocols for a wide range of doping agents has become an important issue for doping control laboratories. This study presents the development and validation of a generic liquid chromatography/time-of-flight mass spectrometry (LC/TOFMS) screening method of 241 small molecule analytes from various categories of prohibited substances (stimulants, narcotics, diuretics, beta(2)-agonists, beta-blockers, hormone antagonists and modulators, glucocorticosteroids and anabolic agents). It is based on a single-step liquid-liquid extraction of hydrolyzed urine and the use of a rapid-resolution liquid chromatography/high-resolution time-of-flight mass spectrometric system acquiring continuous full scan data. Electrospray ionization in the positive mode was used. Validation parameters consisted of identification capability, limit of detection, specificity, ion suppression, extraction recovery, repeatability and mass accuracy. Detection criteria were established on the basis of retention time reproducibility and mass accuracy. The suitability of the methodology for doping control was demonstrated with positive urine samples. The preventive role of the method was proved by the case where full scan acquisition with accurate mass measurement allowed the retrospective reprocessing of acquired data from past doping control samples for the detection of a designer drug, the stimulant 4-methyl-2-hexanamine, which resulted in re-reporting a number of stored samples as positives for this particular substance, when, initially, they had been reported as negatives.

Generic sample preparation combined with high-resolution liquid chromatography-time-of-flight mass spectrometry for unification of urine screening in doping-control laboratories.

A unification of doping-control screening procedures of prohibited small molecule substances--including stimulants, narcotics, steroids, beta2-agonists and diuretics--is highly urgent in order to free resources for new classes such as banned proteins. Conceptually this may be achieved by the use of a combination of one gas chromatography-time-of-flight mass spectrometry method and one liquid chromatography-time-of-flight mass spectrometry method. In this work a quantitative screening method using high-resolution liquid chromatography in combination with accurate-mass time-of-flight mass spectrometry was developed and validated for determination of glucocorticosteroids, beta2-agonists, thiazide diuretics, and narcotics and stimulants in urine. To enable the simultaneous isolation of all the compounds of interest and the necessary purification of the resulting extracts, a generic extraction and hydrolysis procedure was combined with a solid-phase extraction modified for these groups of compounds. All 56 compounds are determined using positive electrospray ionisation with the exception of the thiazide diuretics for which the best sensitivity was obtained by using negative electrospray ionisation. The results show that, with the exception of clenhexyl, procaterol, and reproterol, all compounds can be detected below the respective minimum required performance level and the results for linearity, repeatability, within-lab reproducibility, and accuracy show that the method can be used for quantitative screening. If qualitative screening is sufficient the instrumental analysis may be limited to positive ionisation, because all analytes including the thiazides can be detected at the respective minimum required levels in the positive mode. The results show that the application of accurate-mass time-of-flight mass spectrometry in combination with generic extraction and purification procedures is suitable for unification and expansion of the window of screening methods of doping laboratories. Moreover, the full-scan accurate-mass data sets obtained still allow retrospective examination for emerging doping agents, without re-analyzing the samples.