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2.
Perspect Psychol Sci ; : 17456916241252085, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38752984

RESUMO

We identify points of conflict and consensus regarding (a) controversial empirical claims and (b) normative preferences for how controversial scholarship-and scholars-should be treated. In 2021, we conducted qualitative interviews (n = 41) to generate a quantitative survey (N = 470) of U.S. psychology professors' beliefs and values. Professors strongly disagreed on the truth status of 10 candidate taboo conclusions: For each conclusion, some professors reported 100% certainty in its veracity and others 100% certainty in its falsehood. Professors more confident in the truth of the taboo conclusions reported more self-censorship, a pattern that could bias perceived scientific consensus regarding the inaccuracy of controversial conclusions. Almost all professors worried about social sanctions if they were to express their own empirical beliefs. Tenured professors reported as much self-censorship and as much fear of consequences as untenured professors, including fear of getting fired. Most professors opposed suppressing scholarship and punishing peers on the basis of moral concerns about research conclusions and reported contempt for peers who petition to retract papers on moral grounds. Younger, more left-leaning, and female faculty were generally more opposed to controversial scholarship. These results do not resolve empirical or normative disagreements among psychology professors, but they may provide an empirical context for their discussion.

3.
Drug Test Anal ; 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38785206

RESUMO

The instability of erythropoietin receptor agonists (ERAs, i.e., EPO) in urine presents a challenge to their detectability in doping control samples; however, this issue is not often seen in blood (serum) samples. With the anti-doping field beginning to transition into alternative blood collection technologies, it is important to understand recombinant EPO (rEPO) detectability in serum samples collected from one such capillary collection device, the Tasso+ SST. Twelve individuals were administered a single, 40 IU/kg dose of rEPO (epoetin alfa, EPOGEN®). Following administration, matched urine, venous serum, and capillary serum samples were concurrently collected. Urine aliquots were subject to various storage times and temperatures mimicking shipping conditions of doping control urine samples to assess EPO stability, while other urine aliquots, venous serum, and capillary serum aliquots were frozen until analysis to understand rEPO detectability across all three matrices. EPO and rEPO instability was identified in urine collected from 8 of 12 participants, especially in aliquots stored at room temperature and 37°C. In some of these unstable samples, rEPO was still detectable, while in others, no recombinant nor endogenous EPO was detectable and would have resulted in negative sample reports. Analyzing the concurrently collected urine, venous, and capillary serum samples, rEPO detectability was identical across the three matrices. In most cases, rEPO was detectable for at least 168 h post-administration. Noting greater stability in blood compared with urine, it is recommended that anti-doping authorities utilize this novel capillary serum collection technology to improve overall ERA detectability in doping control samples.

4.
Drug Test Anal ; 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38794805

RESUMO

The monitoring of endogenous steroids in urine has been an important component of the Athlete Biological Passport (ABP) for the last decade. Recently, the quantitation of endogenous steroids in blood has been incorporated into the ABP to increase sensitivity in circumstances where the excretion of urinary ABP biomarkers is low. Current ABP guidelines mandate the use of venous blood draws for blood steroid sample collections, however, recent efforts have focused on investigating the use of less invasive sample collection methods, such as capillary blood collected from the upper arm. The focus of this study was to compare the analytical results of venous and capillary blood collected weekly from 20 individuals, 10 males and 10 females, over six weeks. The two primary biomarkers of the blood steroid ABP module, testosterone (T) and the testosterone/androstenedione (T/A4) ratio, were compared, as well as luteinizing hormone (LH) and the T/LH ratio in male participants, two biomarkers known to be responsive to T use. All biomarkers showed excellent agreement between venous and capillary blood. Longitudinal stability between sample types within individuals was also comparable for all biomarkers. Finally, storage of simultaneously collected capillary samples at room temperature and frozen conditions was compared with evaluate the potential impact of non-cold chain shipping conditions. Most biomarkers showed excellent agreement between frozen and room temperature storage conditions. These results indicate capillary blood collections represent a promising alternative to venous blood collections for the blood steroid module of the ABP.

5.
Evol Psychol ; 22(1): 14747049241238623, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38477637

RESUMO

This research explores how biracial facial cues affect racial perception and social judgment. We tested a coalition-signaling hypothesis of biracial cues in two studies conducted in the United States (n = 227) and China (n = 116). From the perspective of intergroup and interpersonal relations theories in social psychology, biracial features would likely be perceived as cues of threat or resource competition. In contrast, we propose an evolutionary hypothesis that biracial facial cues reveal the ancestral history of intergroup alliances between members of two races or ethnic groups. When racial cues are mixed, we predict that biracial individuals may be viewed more positively than other-race or even own-race members who often compete for limited ingroup resources. The participants observed facial images that ranged from 100% Asian to 100% Caucasian, including morphed biracial composites of 30%, 40%, 50%, 60%, and 70% Caucasian or Asian. The participants evaluated each image regarding perceived Caucasianness (Asianness), attractiveness, trustworthiness, health, intelligence, and career prospects. The US and Chinese samples yielded a similar pattern of own-race bias in racial perception and biracial favoritism in social judgment. The social judgment ratings were not correlated with the racial perception scores and were independent of the sex of the participants or biracial images, indicating a coalitional motive, instead of a mating motive, underlying social perception of biracial individuals. Overall, the results suggest that biracial facial features signal a successful genetic admixture and coalition in parental generations and thus increase the trustworthiness and cooperative potential of a biracial person.


Assuntos
Sinais (Psicologia) , Motivação , Humanos , Evolução Biológica , China , Brancos
6.
Proc Natl Acad Sci U S A ; 120(48): e2301642120, 2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-37983511

RESUMO

Science is among humanity's greatest achievements, yet scientific censorship is rarely studied empirically. We explore the social, psychological, and institutional causes and consequences of scientific censorship (defined as actions aimed at obstructing particular scientific ideas from reaching an audience for reasons other than low scientific quality). Popular narratives suggest that scientific censorship is driven by authoritarian officials with dark motives, such as dogmatism and intolerance. Our analysis suggests that scientific censorship is often driven by scientists, who are primarily motivated by self-protection, benevolence toward peer scholars, and prosocial concerns for the well-being of human social groups. This perspective helps explain both recent findings on scientific censorship and recent changes to scientific institutions, such as the use of harm-based criteria to evaluate research. We discuss unknowns surrounding the consequences of censorship and provide recommendations for improving transparency and accountability in scientific decision-making to enable the exploration of these unknowns. The benefits of censorship may sometimes outweigh costs. However, until costs and benefits are examined empirically, scholars on opposing sides of ongoing debates are left to quarrel based on competing values, assumptions, and intuitions.


Assuntos
Censura Científica , Ciência , Responsabilidade Social , Custos e Análise de Custo
7.
Growth Horm IGF Res ; 72-73: 101560, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37995539

RESUMO

OBJECTIVE: The precise and accurate quantification of human growth hormone (GH) in plasma/ serum is crucial for the diagnosis and treatment of diseases like GH deficiency or acromegaly. However, the ligand-binding assays (LBAs) currently used for routine testing show considerable methodological variability. Here, we present a complementary, combined top-down and bottom-up LC-MS-based method to quantify (intact) GH in plasma and serum, which concurrently provides a basis for a MS-based analysis of GH in doping controls. DESIGN: Extraction of GH from plasma/ serum was accomplished by protein precipitation, followed by an immunocapture step using protein A-coupled magnetic beads and a polyclonal anti-GH antibody. The intact protein was subsequently analyzed top-down on a 2D-LC-HRMS/MS system. In addition, sample extracts were digested with trypsin and analyzed for signal peptides corresponding to 'total', 22 kDa and 20 kDa GH (bottom-up). Both assays were validated according to current guidelines and compared to the GH isoform differential immunoassay used in routine doping control analysis. GH concentrations in serum samples of healthy adults, patients with acromegaly, and in samples obtained after administration of recombinant GH were analyzed as proof-of-principle. RESULTS: The intact monomeric 22 kDa isoform of GH was selectively quantified in a representative working range of 0.5 to 10 ng/ml by top-down LC-HRMS/MS. Subsequent bottom-up analysis provided additional data on 'total' and 20 kDa GH. Top-down and bottom-up assay results for the 22 kDa isoform correlated well with the corresponding immunoassay results (R2 > 0.95). For a possible application of the method in an anti-doping context, the ratio between 22 kDa and 'total' GH was evaluated, indicating differences between the various donor groups, but only with limited significance. CONCLUSION: The top-down and bottom-up LC-HRMS/MS method developed here presents a valuable tool for the quantification of GH in plasma/ serum complementary to established LBAs used at present in clinical measurements. Albeit the examination of the GH isoform proportions by the LC-MS method does not yet allow for the assessment of GH abuse, the obtained findings provide an important basis to enable LC-MS-based GH analysis of doping control samples in the future.


Assuntos
Acromegalia , Dopagem Esportivo , Hormônio do Crescimento Humano , Adulto , Humanos , Acromegalia/diagnóstico , Hormônio do Crescimento , Isoformas de Proteínas
8.
Drug Test Anal ; 15(11-12): 1371-1381, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37749856

RESUMO

The Athlete Biological Passport (ABP) is a longitudinal tool used in anti-doping to monitor biological parameters known to change with performance-enhancing drug use. The ABP consists of multiple modules, including two aimed at detecting the use of endogenous anabolic androgenic steroids: the urinary and serum steroid modules. Human chorionic gonadotropin (hCG) is a protein hormone potentially abused by male athletes to increase the production of endogenous testosterone. To date, no studies have investigated the impact of extended hCG administration on the urinary and serum steroid modules of the ABP. The goal of this study was to identify the impact of multiple hCG administrations on the parameters tracked as part of the urinary and serum steroid modules of the ABP. Ten recreationally active, healthy male individuals self-administered seven 250 µg hCG injections over 3 weeks. Serum and urine samples were collected before, during, and 2 weeks following the final injection. All ABP parameters were quantified in the respective matrix, and steroid profiles were created with Anti-Doping Administration and Management System adaptive model upper and lower limits for both matrices. In both serum and urine profiles, testosterone increased; however, the testosterone/epitestosterone ratio in urine and the testosterone/androstenedione ratio in serum showed minimal changes. Additionally, serum luteinizing hormone (LH) was quantified using an immunoassay, and a serum testosterone/LH ratio was generated. Serum LH values decreased during administration causing large increases in the serum T/LH ratio, indicating this ratio may be a more sensitive parameter for detecting hCG abuse than urinary testosterone/epitestosterone or serum testosterone/androstenedione.


Assuntos
Dopagem Esportivo , Epitestosterona , Humanos , Masculino , Epitestosterona/urina , Androstenodiona , Testosterona/urina , Atletas , Esteroides/urina , Hormônio Luteinizante/urina , Gonadotropina Coriônica/urina , Detecção do Abuso de Substâncias
9.
Behav Brain Sci ; 46: e196, 2023 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-37694927

RESUMO

Madole & Harden develop some good ideas about how to understand genetic causality more clearly, but they frame the benefits of behavior genetics research at a largely collective level, focused on the pros and cons of different ways to engineer the gene pool or social behavior. This neglects the individual benefits of hereditarian insights for mate choice and parenting.


Assuntos
Poder Familiar , Resolução de Problemas , Humanos , Comportamento Social
10.
Rapid Commun Mass Spectrom ; 37(17): e9599, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37580503

RESUMO

A recent study addressed the possibility of unintentional ingestion of clomiphene through residues in chicken eggs. The method developed here helped distinguish between microdose intake of (E/Z)-clomiphene citrate and consumption of clomiphene-containing eggs by the urinary pattern of four mono-hydroxylated clomiphene metabolites. However, reanalyses of doping-control samples, which showed an adverse analytical finding for clomiphene, revealed a hydroxy clomiphene (HC) isomer that was not found after microdose intake or after consumption of clomiphene-containing eggs and could not be assigned to any of the available reference compounds. The aim of the present follow-up study was to identify this HC isomer and to characterize this metabolite with respect to its potential properties as long-term metabolite in doping controls. METHODS: (E/Z)-3'-HC and (E/Z)-4'-HC were synthesized involving the McMurry reaction. An ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was developed and optimized after a derivatization step with dansyl chloride to separate eight HC isomers. Using this method, urine samples from a controlled clomiphene administration study were analyzed, in which male study participants received therapeutic doses of clomiphene for 30 days and collected urine samples for up to 8 months. Thus, isomer-specific HC elimination profiles could be monitored. RESULTS: The metabolite previously found in doping-control samples was identified as (Z)-3'-HC. The elimination profiles of the different HCs confirmed previous results, with (Z)-3-HC being the most abundant urinary hydroxy metabolite shortly after administration. A new finding was that the data suggest that (Z)-3'-HC is excreted at higher relative concentrations only several weeks after drug intake. CONCLUSION: These findings might be of particular importance in sport drug testing as they can assist in the decision-making process to distinguish between intentional doping and inadvertent exposure to clomiphene via food contamination.


Assuntos
Dopagem Esportivo , Masculino , Animais , Clomifeno/urina , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida/métodos , Seguimentos
11.
Clin Chem ; 69(7): 754-762, 2023 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-37253044

RESUMO

BACKGROUND: Human chorionic gonadotropin (hCG) detection is indicative of pregnancy and can be indicative of some forms of cancerous tumors. The hCG drug itself, however, is a performance enhancing substance used by male athletes to increase testosterone production. Antidoping testing for hCG is conducted in urine, often on immunoanalyzer platforms, many of which utilize biotin-streptavidin dependent immunoassays in which the presence of biotin in samples is a known confounding factor. While biotin interference in serum has been well-studied, the extent of biotin interference in urine has not. METHODS: Ten active male individuals underwent a 2-week hCG administration protocol concurrent with supplementation with biotin (20 mg/day) or placebo. Urine and serum samples were collected throughout the study and analyzed for hCG and biotin concentrations. RESULTS: Urinary biotin levels in the hCG + biotin group increased 500-fold over baseline and 29-fold over corresponding serum biotin levels after biotin supplementation. When using a biotin-dependent immunoassay, the hCG + placebo group produced hCG-positive results (hCG ≥ 5 mIU/mL) in 71% of urine samples, while the hCG + biotin group produced positive results in only 19% of samples. Both groups had elevated hCG values in serum measurements by a biotin-dependent immunoassay and in urine when using a biotin-independent immunoassay. Urinary hCG measurements and biotin levels from the hCG + biotin group showed a negative correlation (Spearman r = -0.46, P < 0.0001) when measured using a biotin-dependent immunoassay. CONCLUSIONS: Biotin supplementation can severely suppress urinary hCG values in assays utilizing biotin-streptavidin binding methods and therefore these types of assays are not recommended for use in urine samples containing high levels of biotin. Clinicaltrials.gov Registration Number: NCT05450900.


Assuntos
Biotina , Gonadotropina Coriônica , Gravidez , Feminino , Humanos , Masculino , Estreptavidina , Imunoensaio/métodos , Suplementos Nutricionais
12.
Drug Test Anal ; 14(11-12): 1962-1973, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36114153

RESUMO

Hematological results in the context of the Athlete Biological Passport (ABP) from a placebo-controlled EPO administration study are provided here. Twelve participants administered eight subcutaneous boosting doses of epoetin alfa (at 40 IU/kg) over the course of 20 days. After a 10-day washout period, the same volunteers administered six microdoses (900 IU), intravenously, over 13 days. A blinded placebo cohort followed the same dosing pattern, administering saline instead of EPO. All participants supplemented with oral iron, daily, throughout the entirety of the study. In the EPO cohort, as expected, significant changes from baseline were identified in IRF, RET#, RET%, RDW, HCT, HGB, and RBC. No meaningful changes were identified in the placebo cohort population. From the ABP perspective, atypical passport findings (ATPF) were identified in 49% of the samples collected during the boosting and initial washout phases, and 24% of the samples during the microdosing and final washout phases. ATPFs from this cohort were flagged as late as Day 70, the final day of the study. Only a single ATPF was identified from all samples collected from the placebo cohort. ABPs from all volunteers in the study are provided as an avenue to visually convey differences in magnitude and timing of the hematological changes caused by EPO on the individual level. These data are expected to provide important content for Athlete Passport Management Units and ABP expert panels alike.


Assuntos
Dopagem Esportivo , Eritropoetina , Humanos , Masculino , Atletas , Dopagem Esportivo/métodos , Método Duplo-Cego , Epoetina alfa , Ensaios Clínicos Controlados como Assunto
13.
Clin Chem ; 68(10): 1281-1291, 2022 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-35906802

RESUMO

BACKGROUND: The development of analytical approaches to help reduce the risk of growth hormone (GH) doping is important to fair competition and the health of athletes. However, the reliable detection of GH use remains challenging. The identification of novel biomarkers of GH administration could lead to a better understanding of the physiological response to GH, more sensitive detection of the illicit use of GH in sport, and better management of patients treated for GH disorders. METHODS: We developed a targeted liquid chromatography-tandem mass spectrometry method to simultaneously quantify the carboxyl-terminal propeptide of type III procollagen (P-III-CP) and type III collagen degradation products in human serum. Following proteolysis, we instituted a simple acid precipitation step to reduce digested sample complexity before peptide immunoenrichment, which improved the recovery of one target peptide from serum. We evaluated the concentration of each biomarker at different age ranges and after GH administration in healthy participants. RESULTS: The assay was linear over an estimated concentration range of 0.3 to1.0 nM and 0.1 to 0.4 nM for each surrogate peptide of P-III-CP and collagen fragments, respectively. Intra-day and inter-day coefficients of variation were ≤15%. Biomarker concentrations appeared to vary with age and to reflect age-specific collagen turnover. Moreover, their concentrations changed after GH administration. CONCLUSIONS: Our method quantifies the proteins belonging to the family of P-III-CP and type III collagen degradation products in human serum, which could be used to detect GH administration in athletes and better understand diseases involving GH therapy or altered type III collagen turnover.


Assuntos
Hormônio do Crescimento Humano , Pró-Colágeno , Biomarcadores , Cromatografia Líquida , Colágeno , Colágeno Tipo III , Hormônio do Crescimento , Humanos , Fator de Crescimento Insulin-Like I/análise , Fragmentos de Peptídeos , Peptídeos , Espectrometria de Massas em Tandem
14.
Drug Test Anal ; 14(7): 1255-1263, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35249266

RESUMO

A multiphase study was designed to examine the detectability of human growth hormone (GH) use in capillary dried blood spots (DBS). First, 13 subjects self-injected a single, 2-mg dose of somatropin and collected capillary DBS samples for 24 h. Next, nine subjects self-injected 2-mg somatropin, six times over the course of 11 days; DBS were collected intermittently following dosing. Finally, a nondrug, large-scale field study involved DBS collections from an athlete and staff population over 3 years. All DBS samples were self-collected using the Tasso M20 device and were analyzed for the presence of GH using the WADA-approved GH isoforms test. Following the single dose, positive detection within 12 h of dosing was 86% and 56% sensitive on Kits 1 and 2, respectively. In the multidose study, detection within 12 h was 85% and 69% sensitive on Kits 1 and 2, respectively. No positives were detected outside the 12-h window following a single dose, wherein detection was 5.6% sensitive at 24-h in the multidose study. Combining the 12-h windows from both studies, 100% of samples had measurable recombinant (REC) and pituitary (PIT) GH concentrations above the assay LoD, 0.041 ng/ml. Finally, 1213 samples were collected in the large-scale field study: 189 showed REC and PIT concentrations above the LoD; none returned positive results. GH is detectable in capillary DBS using the isoforms method for 12-24 h following use. While detection is short lived, transitioning to a DBS self-collection method can allow more frequent testing and increase deterrence to GH abuse.


Assuntos
Hormônio do Crescimento Humano , Teste em Amostras de Sangue Seco/métodos , Hormônio do Crescimento , Humanos , Isoformas de Proteínas , Proteínas Recombinantes
15.
Drug Test Anal ; 14(7): 1291-1299, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35302295

RESUMO

The hematological module of the Athlete Biological Passport (ABP) represents an important tool in the pursuit to detect blood doping in athletes. Currently, collecting blood samples for ABP analysis can be cumbersome, invasive, and expensive, involving a venous blood draw performed by a trained phlebotomist followed by cold-chain monitored shipping to the analysis laboratory. Developing innovative methods to collect and transport ABP blood samples while adhering to strict preanalytical and analytical requirements has the potential to greatly increase testing frequency and, consequently, the effectiveness of the ABP program globally. The focus of this study was to compare venous blood collections with capillary blood collections to determine if capillary samples could be used for ABP analysis without sacrificing the analytical integrity required for antidoping testing procedures. In this study, capillary blood was collected using the Tasso+ EDTA device (Tasso, Inc.), a novel microvolumetric device that collects liquid, whole blood from skin capillaries on the upper arm. Excellent laboratory agreement was observed between venous and capillary blood samples for the three main ABP parameters: HGB, RET%, and OFF-Score. Additionally, the stability of capillary samples after storage at 4°C, similar to what would be required during transport, was acceptable for up to 72 h following collection. Finally, we generated individual ABP profiles using the adaptive model for 10 participants and observed excellent agreement between venous and capillary profiles. These results indicate capillary blood collection is a viable alternative to venous blood collections for ABP analysis.


Assuntos
Capilares , Dopagem Esportivo , Atletas , Estudos de Viabilidade , Humanos
16.
Drug Test Anal ; 14(5): 826-832, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-34216436

RESUMO

The hematological module of the Athlete Biological Passport (ABP) is used for indirect detection of blood manipulations; however, the use of this method to detect doping, such as with microdoses of recombinant human erythropoietin (rhEPO), is problematic. For this reason, the sensitivity of ABP must be enhanced by implementing novel biomarkers. Here, we show that 5'-aminolevulinate synthase 2 (ALAS2) mRNAs are useful transcriptomic biomarkers to improve the indirect detection of rhEPO microdosing. Moreover, the sensitivity was sufficient to distinguish rhEPO administration from exposure to hypoxic conditions. Levels of mRNAs encoding carbonate anhydrase 1 (CA1) and solute carrier family 4 member 1 (SLC4A1) RNA, as well as the linear (L) and linear + circular (LC) forms of ALAS2 mRNA, were monitored for 16 days after rhEPO microdosing and during exposure to hypoxic conditions. ALAS2 mRNAs increased by 300% compared with the baseline values after rhEPO microdosing. Moreover, ALAS2 mRNAs were not significantly increased under hypoxic conditions. By contrast, CA1 mRNA was increased after both rhEPO microdosing and hypoxia, whereas SLC4A1 mRNA did not significantly increase under either condition. Furthermore, the analyses described here were performed using dried blood spots (DBSs), which provide advantages in terms of the sample collection, transport, and storage logistics. This study demonstrates that ALAS2 mRNA levels are sensitive and specific transcriptomic biomarkers for the detection of rhEPO microdosing using the hematological module of the ABP, and this method is compatible with the use of DBSs for anti-doping analyses.


Assuntos
Dopagem Esportivo , Eritropoetina , 5-Aminolevulinato Sintetase/genética , Biomarcadores , Dopagem Esportivo/métodos , Humanos , Hipóxia , RNA , RNA Mensageiro/genética , Proteínas Recombinantes
17.
Am J Hematol ; 96(12): 1621-1629, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34626008

RESUMO

Athletes abuse recombinant human erythropoietin (rhEPO) and erythropoiesis stimulating agents to increase hemoglobin mass and improve performance. To evade detection, athletes have developed sophisticated blood doping regimens, which often include rhEPO micro-dosing. Detection of these methods requires biomarkers with increased sensitivity and a sample matrix that is more amenable to frequent testing in the field. We have developed a method to measure two immature reticulocyte proteins, CD71 and ferrochelatase (FECH), and one total erythrocyte protein, Band 3, in dried blood spots (DBS). This method was tested in response to rhEPO administration after low doses, 40 IU/kg, micro-doses, 900 IU, or saline injection in 20 healthy subjects. During administration of low-dose rhEPO, the mean CD71/Band 3 and FECH/Band 3 ratio increased by 412 ± 197% and 250 ± 44%, respectively. The mean response for the current biomarker, RET%, increased by 195 ± 35%. During administration of rhEPO micro-doses, CD71/Band 3 increased to 127 ± 25% on day 35 and 139 ± 36% on day 39, while no increase was observed in RET%. After rhEPO administration, during the washout phase, mean values decreased to a minimum of 64 ± 4% and 64 ± 11% for CD71/Band 3 and RET%, respectively. However, CD71/Band 3 remained below 75% of baseline for at least 4 weeks after rhEPO injection, while RET% returned to baseline levels. The results demonstrate that immature reticulocyte proteins have a larger response to rhEPO administration than the current biomarker, RET%, and can be monitored in the DBS matrix.


Assuntos
Teste em Amostras de Sangue Seco/métodos , Eritropoetina/sangue , Reticulócitos/química , Detecção do Abuso de Substâncias/métodos , Adolescente , Adulto , Rastreamento de Células/métodos , Eritropoetina/administração & dosagem , Eritropoetina/análise , Humanos , Masculino , Pessoa de Meia-Idade , Efeito Placebo , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/análise , Proteínas Recombinantes/sangue , Reticulócitos/citologia , Adulto Jovem
18.
Clin Chem ; 67(8): 1071-1079, 2021 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-33993255

RESUMO

BACKGROUND: Immature reticulocytes (IRC) are the first cells to respond to changes in erythropoiesis. For antidoping applications, measurement of IRC may improve detection of blood doping practices. Unfortunately, this small cell population has limited stability in liquid blood samples and is difficult to measure with optimal precision. We developed a method to measure 3 IRC membrane proteins in dried blood spots (DBS) to monitor changes in erythropoiesis. METHODS: DBS spots were washed with buffers to remove soluble proteins, membrane proteins remaining in the spot were digested with trypsin, and one peptide for each protein was measured by LC-MS/MS. IRC protein concentration was determined using a DBS single point calibrator. RESULTS: Intraassay precision for IRC proteins was between 5%-15%. IRC proteins were stable in DBS for 29 days at room temperature. In a longitudinal study of 25 volunteers, the mean intraindividual variation for 3 IRC proteins was 17%, 20%, and 24% from capillary blood DBS. In comparison, the mean longitudinal variation for IRC counts measured on an automated hematology analyzer was 38%. IRC protein concentration from capillary blood DBS correlated well with venous blood DBS protein concentrations. CONCLUSIONS: Measurement of IRC proteins in DBS samples provides a method to measure changes in erythropoiesis with improved analytical sensitivity, stability, and precision. When combined with the inherent advantages of capillary blood collection in the field, this method may substantially improve the detection of blood doping practices.


Assuntos
Teste em Amostras de Sangue Seco , Reticulócitos , Cromatografia Líquida/métodos , Teste em Amostras de Sangue Seco/métodos , Humanos , Estudos Longitudinais , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem/métodos
19.
Drug Test Anal ; 13(7): 1270-1281, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33629499

RESUMO

The steroidal module of the Athlete Biological Passport (ABP) has been used since 2014 for the longitudinal monitoring of urinary testosterone and its metabolites to identify samples suspicious for the use of synthetic forms of Endogenous Anabolic Androgenic Steroids (EAAS). Multiple recent studies have suggested that monitoring of blood parameters may provide enhanced detectability of exogenous testosterone administration. Transdermal and intramuscular testosterone administration studies were carried out in 15 subjects, and the effect on blood steroidal levels, hematological parameters, and gonadotropins was evaluated. Serum testosterone and dihydrotestosterone levels increased while gonadotropin levels were suppressed after administration. A modest increase in reticulocytes was also observed. The blood parameters that were responsive to the administrations were combined into several linear discriminant models targeting both administration (on) and washout (off) phases. The models were effective in detecting the large dose intramuscular administration but were less successful in the detection of the lower dose transdermal application. The blood profiling models may provide complementary value but do not appear to be substantially more advantageous than longitudinal urinary profiling.


Assuntos
Androgênios/sangue , Dopagem Esportivo/prevenção & controle , Detecção do Abuso de Substâncias/métodos , Testosterona/análogos & derivados , Administração Cutânea , Adulto , Estudos Cross-Over , Di-Hidrotestosterona/sangue , Análise Discriminante , Relação Dose-Resposta a Droga , Géis , Humanos , Injeções Intramusculares , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Reticulócitos/metabolismo , Testosterona/administração & dosagem , Testosterona/sangue
20.
Drug Test Anal ; 12(11-12): 1554-1560, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32697436

RESUMO

Identification and evaluation of long-term markers is crucial in prolonging the detection window for anabolic steroid abuse in sport. Recently, sulfoconjugated epiandrosterone was identified as a potential long-term marker for the abuse of certain endogenous anabolic agents, including testosterone, which continues to be widely used as a performance enhancing agent in sport. To evaluate the applicability of epiandrosterone sulfate as a marker for testosterone use, administration studies were conducted with multiple modes of testosterone administration - transdermal, intramuscular, and subcutaneous. A modified sample preparation method was used to collect both glucuronidated and sulfoconjugated analytes of interest. Carbon isotope ratio measurements from the administration studies are presented here. Epiandrosterone was less effective than the conventionally used target compounds for detection of the low dose application (transdermal gel). With intramuscular administration, epiandrosterone was more diagnostic than with transdermal administration, but it did not prolong the detection window more than the conventional target compounds. With subcutaneous administration, the doses administered to the subjects were varied and the effect on the epiandrosterone values was dependent on the magnitude of the dose administered. Epiandrosterone does not appear to be a useful marker in the detection of low dose testosterone administration. It is responsive to higher dose administration, but it does not provide an extension of the detection window relative to conventional target compounds.


Assuntos
Anabolizantes/administração & dosagem , Anabolizantes/metabolismo , Androsterona/metabolismo , Detecção do Abuso de Substâncias/normas , Testosterona/administração & dosagem , Testosterona/metabolismo , Administração Cutânea , Adulto , Anabolizantes/análise , Androsterona/análise , Biomarcadores/metabolismo , Dopagem Esportivo/métodos , Dopagem Esportivo/prevenção & controle , Cromatografia Gasosa-Espectrometria de Massas/métodos , Cromatografia Gasosa-Espectrometria de Massas/normas , Géis , Humanos , Injeções Intramusculares , Injeções Subcutâneas , Absorção Intramuscular/efeitos dos fármacos , Absorção Intramuscular/fisiologia , Masculino , Absorção Cutânea/efeitos dos fármacos , Absorção Cutânea/fisiologia , Absorção Subcutânea/efeitos dos fármacos , Absorção Subcutânea/fisiologia , Detecção do Abuso de Substâncias/métodos , Testosterona/análise
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