X

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Online Resource
    Online Resource
    Disposition of Urinary and Serum Steroid Metabolites in Response to Testosterone Administration in Healthy Women
    The Endocrine Society ; 2021
    In:  The Journal of Clinical Endocrinology & Metabolism Vol. 106, No. 3 ( 2021-03-08), p. 697-707
    Details
    In: The Journal of Clinical Endocrinology & Metabolism, The Endocrine Society, Vol. 106, No. 3 ( 2021-03-08), p. 697-707
    Abstract: Little is known about how exogenous testosterone (T) affects the steroid profile in women. More knowledge would give the antidoping community keys as to how to interpret tests and detect doping. Objective This work aimed to investigate the steroid profile in serum and urine in young healthy women after T administration. Methods In a randomized, double-blind, placebo-controlled study, 48 healthy young women were assigned to daily treatment with T cream (10 mg) or placebo (1:1) for 10 weeks. Urine and blood were collected before and at the end of treatment. Serum steroids were analyzed with liquid chromatography–tandem mass spectrometry, and urine levels of T, epitestosterone (E), and metabolites included in the Athlete Biological Passport (ABP) were analyzed with gas chromatography–tandem mass spectrometry. Results In serum, T and dihydrotestosterone levels increased, whereas sex hormone–binding globulin and 17-hydroxyprogesterone decreased after T treatment as compared to placebo. In urine, T and 5α-androstanediol increased in the T group. The median T increase in serum was 5.0-fold (range, 1.2-18.2) and correlated to a 2.2-fold (range, 0.4-14.4) median increase in T/E in urine (rs = 0.76). Only 2 of the 24 women receiving T reached the T/E cutoff ratio of 4, whereas when the results were added to the ABP, 6 of 15 participants showed atypically high T/E (40%). In comparison, 22/24 women in the T group increased serum T more than 99.9% of the upper confidence interval of nontreated values. Conclusion It seems that the T/E ratio is not sufficient to detect exogenous T in women. Serum total T concentrations could serve as a complementary marker of doping.
    Type of Medium: Online Resource
    ISSN: 0021-972X , 1945-7197
    URL: Article
    DOI: 10.1210/clinem/dgaa904
    RVK:
    XA 10000
    Language: English
    Publisher: The Endocrine Society
    Publication Date: 2021
    detail.hit.zdb_id: 2026217-6
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Online Resource
    Open Access Request
    Availability (electronic / print)
  • 2
    Online Resource
    Online Resource
    Impact of hormonal contraceptives on urinary steroid profile in relation to serum hormone changes and CYP17A1 polymorphism
    Wiley ; 2019
    In:  Drug Testing and Analysis Vol. 11, No. 9 ( 2019-09), p. 1284-1289
    Details
    In: Drug Testing and Analysis, Wiley, Vol. 11, No. 9 ( 2019-09), p. 1284-1289
    Abstract: To detect doping with endogenous steroids, six urinary steroids are longitudinally monitored in the athlete biological passport (ABP). These steroids include testosterone, etiocholanolone, androsterone, 5α‐androstane‐3α,17β‐diol, 5β‐androstane‐3α,17β‐diol, and the testosterone isomer epitestosterone. It is known that the intake of hormonal contraceptives may interfere with the ABP biomarkers. A previous study showed that athletes using hormonal contraceptives (HCs) display lower urinary epitestosterone concentrations than non‐using athletes. In this study, we analyzed the urinary steroid profile prior to and three months after administration of an oral HC including levonorgestrel and ethinylestradiol ( n  = 55). The urinary concentrations of all the ABP metabolites decreased after three months, with epitestosterone showing the largest decline (median 6.78 to 3.04 ng/mL, p˂0.0001) followed by 5α‐androstane‐3α,17β‐diol (median 23.5 to 12.83 ng/mL, p˂0.0001), and testosterone (median 5.32 to 3.66, p˂0.0001). Epitestosterone is included in two of the five ratios in the ABP (T/E and 5αAdiol/E), and consequently these ratios increased 1.7‐fold (range 0.27 to 8.50) and 1.26‐fold (range 0.14 to 5.91), respectively. Some of these changes may mimic the changes seen after administration of endogenous steroids leading to atypical findings. Notably, even though participants used the same contraceptive treatment schedule, the HC‐mediated epitestosterone change varied to a large extent (median 0.43‐fold, range 0.06 to 6.5) and were associated with a functional T˃C promoter polymorphism in CYP17A1 . Moreover, the epitestosterone changes correlated with HC‐induced testosterone and gonadotropins changes in serum, indicating that urinary epitestosterone reflects the androgen load in HC‐using women.
    Type of Medium: Online Resource
    ISSN: 1942-7603 , 1942-7611
    URL: Issue
    URL: Article
    DOI: 10.1002/dta.v11.9
    DOI: 10.1002/dta.2663
    Language: English
    Publisher: Wiley
    Publication Date: 2019
    detail.hit.zdb_id: 2462344-1
    SSG: 15,3
    SSG: 31
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Online Resource
    Open Access Request
    Availability (electronic / print)
  • 3
    Online Resource
    Online Resource
    DataSheet2.PDF
    Frontiers Media SA ; 2022
    In:  Frontiers in Physiology Vol. 13 ( 2022-5-3)
    Details
    In: Frontiers in Physiology, Frontiers Media SA, Vol. 13 ( 2022-5-3)
    Abstract: Administration of testosterone (T) is associated with increased serum T concentrations and improved physical performance in women. However, the inter-individual variation in T concentrations after T treatment is large and may in part be due to genetic variations. Serum T, as well as dihydrotestosterone (DHT), androstenedione (A) and the T/A ratio have been suggested as promising doping biomarkers for testosterone intake. Here, polymorphisms in androgen metabolic enzyme genes have been investigated in healthy women prior to and after 10 weeks administration of testosterone cream. Klotho is a protein that has been associated with anaerobic strength and here a genetic variation in klotho gene was studied in relation to performance as measured by isokinetic knee strength, as well as to serum androgen disposition. The AKR1C3 genotype (rs12529) was associated with serum T levels at baseline, whereas serum concentrations post T treatment did not differ between genotypes. The SLCO2B1 (rs12422149) and UGT2B17 deletion polymorphisms were not associated with serum concentration of either T, DHT or A. The klotho polymorphism (rs9536314) was associated with serum concentrations of both total T and T/A ratio after T administration. Individuals with the GT genotype increased T concentrations and T/A ratio more than women homozygous for the T allele. No significant difference in the association of klotho genotype with knee muscle strength was observed between placebo and T treatment. However, individuals homozygous for the T allele showed higher isometric mean torque scores at exit than GT subjects after T administration. This is the first time a genotype has been associated with androgen concentrations after T administration and muscle strength in women. Our results imply that subjects with a polymorphism in klotho may be more prone to detection using serum T and A as biomarkers.
    Type of Medium: Online Resource
    ISSN: 1664-042X
    URL: Article
    URL: Article
    URL: Article
    DOI: 10.3389/fphys.2022.844133
    DOI: 10.3389/fphys.2022.844133.s001
    DOI: 10.3389/fphys.2022.844133.s002
    Language: Unknown
    Publisher: Frontiers Media SA
    Publication Date: 2022
    detail.hit.zdb_id: 2564217-0
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Online Resource
    Open Access Request
    Availability (electronic / print)
  • 4
    Online Resource
    Online Resource
    Enhanced Skeletal Muscle Oxidative Capacity and Capillary-to-Fiber Ratio Following Moderately Increased Testosterone Exposure in Young Healthy Women
    Frontiers Media SA ; 2020
    In:  Frontiers in Physiology Vol. 11 ( 2020-12-3)
    Details
    In: Frontiers in Physiology, Frontiers Media SA, Vol. 11 ( 2020-12-3)
    Abstract: Background: Recently, it was shown that exogenously administered testosterone enhances endurance capacity in women. In this study, our understanding on the effects of exogenous testosterone on key determinants of oxygen transport and utilization in skeletal muscle is expanded. Methods: In a double-blinded, randomized, placebo-controlled trial, 48 healthy active women were randomized to 10 weeks of daily application of 10 mg of testosterone cream or placebo. Before and after the intervention, VO 2 max, body composition, total hemoglobin (Hb) mass and blood volumes were assessed. Biopsies from the vastus lateralis muscle were obtained before and after the intervention to assess mitochondrial protein abundance, capillary density, capillary-to-fiber (C/F) ratio, and skeletal muscle oxidative capacity. Results: Maximal oxygen consumption per muscle mass, Hb mass, blood, plasma and red blood cell volumes, capillary density, and the abundance of mitochondrial protein levels (i.e., citrate synthase, complexes I, II, III, IV-subunit 2, IV-subunit 4, and V) were unchanged by the intervention. However, the C/F ratio, specific mitochondrial respiratory flux activating complex I and linked complex I and II, uncoupled respiration and electron transport system capacity, but not leak respiration or fat respiration, were significantly increased following testosterone administration compared to placebo. Conclusion: This study provides novel insights into physiological actions of increased testosterone exposure on key determinants of oxygen diffusion and utilization in skeletal muscle of women. Our findings show that higher skeletal muscle oxidative capacity coupled to higher C/F ratio could be major contributing factors that improve endurance performance following moderately increased testosterone exposure.
    Type of Medium: Online Resource
    ISSN: 1664-042X
    URL: Article
    DOI: 10.3389/fphys.2020.585490
    Language: Unknown
    Publisher: Frontiers Media SA
    Publication Date: 2020
    detail.hit.zdb_id: 2564217-0
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Online Resource
    Open Access Request
    Availability (electronic / print)
  • 5
    Online Resource
    Online Resource
    Effects of moderately increased testosterone concentration on physical performance in young women: a double blind, randomised, placebo controlled study
    BMJ ; 2020
    In:  British Journal of Sports Medicine Vol. 54, No. 10 ( 2020-05), p. 599-604
    Details
    In: British Journal of Sports Medicine, BMJ, Vol. 54, No. 10 ( 2020-05), p. 599-604
    Abstract: To investigate the effects of a moderate increase in serum testosterone on physical performance in young, physically active, healthy women. Methods A double blind, randomised, placebo controlled trial was conducted between May 2017 and June 2018 (ClinicalTrials.gov ID: NCT03210558 ). 48 healthy, physically active women aged 18–35 years were randomised to 10 weeks of treatment with 10 mg of testosterone cream daily or placebo (1:1). All participants completed the study. The primary outcome measure was aerobic performance measured by running time to exhaustion (TTE). Secondary outcomes were anaerobic performance (Wingate test) and muscle strength (squat jump (SJ), counter movement jump (CMJ) and knee extension peak torque). Hormone levels were analysed and body composition assessed by dual energy X-ray absorptiometry. Results Serum levels of testosterone increased from 0.9 (0.4) nmol/L to 4.3 (2.8) nmol/L in the testosterone supplemented group. TTE increased significantly by 21.17 s (8.5%) in the testosterone group compared with the placebo group (mean difference 15.5 s; P=0.045). Wingate average power, which increased by 15.2 W in the testosterone group compared with 3.2 W in the placebo group, was not significantly different between the groups (P=0.084). There were no significant changes in CMJ, SJ and knee extension. Mean change from baseline in total lean mass was 923 g for the testosterone group and 135 g for the placebo group (P=0.040). Mean change in lean mass in the lower limbs was 398 g and 91 g, respectively (P=0.041). Conclusion The study supports a causal effect of testosterone in the increase in aerobic running time as well as lean mass in young, physically active women.
    Type of Medium: Online Resource
    ISSN: 0306-3674 , 1473-0480
    URL: Article
    DOI: 10.1136/bjsports-2018-100525
    Language: English
    Publisher: BMJ
    Publication Date: 2020
    detail.hit.zdb_id: 2003204-3
    SSG: 31
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Online Resource
    Open Access Request
    Availability (electronic / print)
  • 6
    Online Resource
    Online Resource
    Development and initial validation of a Swedish inventory to screen for symptoms of deficient perineum in women after vaginal childbirth: ‘Karolinska Symptoms After Perineal Tear Inventory’
    Springer Science and Business Media LLC ; 2022
    In:  BMC Pregnancy and Childbirth Vol. 22, No. 1 ( 2022-08-13)
    Details
    In: BMC Pregnancy and Childbirth, Springer Science and Business Media LLC, Vol. 22, No. 1 ( 2022-08-13)
    Abstract: Perineal tears are common after vaginal birth and may result in pelvic floor symptoms. However, there is no validated questionnaire that addresses long-term symptoms in women with a deficient perineum after vaginal birth. Thus, the objective of this study was to develop and psychometrically evaluate a clinical screening inventory that estimates subjective symptoms in women with a deficient perineum more than one year after vaginal delivery. Material and methods The development and psychometric evaluation employed both qualitative and quantitative methods. Qualitative strategies involved content validity and Think Aloud protocol for generation of items. The psychometric evaluation employed principal component analysis to reduce the number of items. The inventory was completed by women with persistent symptoms after perineal tears ( N  = 170). Results were compared to those of primiparous women giving birth by caesarean section ( N  = 54) and nulliparous women ( N  = 338). Results A preliminary 41-item inventory was developed, and the psychometric evaluation resulted in a final 11-item inventory. Women with confirmed deficient perineum after perineal trauma scored significantly higher on the symptoms inventory than women in control groups. A cut-off value of ≥ 8 could distinguish patients from controls with high sensitivity (100%) and specificity (87–91%). Conclusions The Karolinska Symptoms After Perineal Tear Inventory, is a psychometrically valid 11-item patient-reported outcome measure for symptoms of deficient perineum more than one year after vaginal birth. More research is needed to validate the inventory in various patient populations as well as its use in pelvic floor interventions. The inventory has the potential to improve patient counseling and care in the future.
    Type of Medium: Online Resource
    ISSN: 1471-2393
    URL: Article
    DOI: 10.1186/s12884-022-04964-w
    Language: English
    Publisher: Springer Science and Business Media LLC
    Publication Date: 2022
    detail.hit.zdb_id: 2059869-5
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Online Resource
    Open Access Request
    Availability (electronic / print)
  • 7
    Online Resource
    Online Resource
    Disposition of serum steroids in response to combined oral contraceptives and menstrual cycle phases: A double‐blind, randomized, placebo‐controlled study
    Wiley ; 2023
    In:  Drug Testing and Analysis Vol. 15, No. 1 ( 2023-01), p. 134-138
    Details
    In: Drug Testing and Analysis, Wiley, Vol. 15, No. 1 ( 2023-01), p. 134-138
    Abstract: To analyze doping control samples from female athletes demands understanding of non‐doping factors that affect the steroid profile. These could be physiological factors such as exercise, alcohol consumption, hormonal changes during the menstrual cycle, or the effect of commonly used approved drugs like combined oral contraceptives. Urine samples have been the main way of doping testing, but serum samples are proposed as a complement. Testosterone, dihydrotestosterone, or the ratio of testosterone and androstenedione has been proposed as a biomarker for testosterone doping because it increases after transdermal testosterone administration. In this double‐blind, randomized, placebo‐controlled study of 340 healthy females, we analyzed the serum steroid levels, including glucuronide metabolites, before and after 3 months of combined oral contraceptives or placebo. At follow up, sample collection in the placebo group was randomly distributed between different menstrual cycle phases. This enabled to analyze changes in concentrations between the follicular, ovulation, and luteal phases. Combined oral contraceptives decreased all serum steroids including the glucuronide metabolites. As expected, serum testosterone levels increased during the ovulation phase, and also androstenedione and androstenediol, whereas the glucuronide metabolites remained unaffected. Neither combined oral contraceptives nor menstrual cycle phases did affect the ratio of testosterone and androstenedione in serum, and consequently this ratio seems promising as a marker of doping with endogenous anabolic androgenic steroids in women.
    Type of Medium: Online Resource
    ISSN: 1942-7603 , 1942-7611
    URL: Issue
    URL: Article
    DOI: 10.1002/dta.v15.1
    DOI: 10.1002/dta.3373
    Language: English
    Publisher: Wiley
    Publication Date: 2023
    detail.hit.zdb_id: 2462344-1
    SSG: 15,3
    SSG: 31
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Online Resource
    Open Access Request
    Availability (electronic / print)
Nothing or not found what you are looking for? Please check your search query or use the Interlibrary Loan Search.
Close ⊗
This website uses cookies and the analysis tool Matomo. Further information can be found on the KOBV privacy pages