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- Ohlsson, Claes, 1965, et al.
(författare)
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Comparisons of Immunoassay and Mass Spectrometry Measurements of Serum Estradiol Levels and Their Influence on Clinical Association Studies in Men
- 2013
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Ingår i: Journal of Clinical Endocrinology & Metabolism. - : The Endocrine Society. - 0021-972X .- 1945-7197. ; 98:6
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Tidskriftsartikel (refereegranskat)abstract
- Context: Immunoassay-based techniques, routinely used to measure serum estradiol (E2), are known Objective: Our objective was to compare immunoassay and MS measurements of E2 levels in men and Design and Setting: Middle-aged and older male subjects participating in the population-based Main Outcome Measures: Immunoassay and MS measurements of serum E2 were compared and Results: Within each cohort, serum E2 levels obtained by immunoassay and MS correlated moderately Conclusions: Our findings suggest interference in the immunoassay E2 analyses, possibly by CRP or a
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| 2. |
- Vanderschueren, D., et al.
(författare)
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Gonadal sex steroid status and bone health in middle-aged and elderly European men
- 2010
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Ingår i: Osteoporosis International. - : Springer Science and Business Media LLC. - 1433-2965 .- 0937-941X. ; 21:8, s. 1331-1339
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Tidskriftsartikel (refereegranskat)abstract
- The influence of sex steroids on calcaneal quantitative ultrasound (QUS) parameters was assessed in a population sample of middle-aged and elderly European men. Higher free and total E-2 though not testosterone, were independently associated with higher QUS parameters. The aim of this study was to investigate the association between QUS parameters and sex steroids in middle-aged and elderly European men. Three thousand one hundred forty-one men aged between 40 and 79 years were recruited from eight European centres for participation in a study of male ageing: the European Male Ageing Study. Subjects were invited by letter to attend for an interviewer-administered questionnaire, blood sample and QUS of the calcaneus (Hologic-SAHARA). Blood was assessed for sex steroids including oestradiol (E-2), testosterone (T), free and bio-available E-2 and T and sex hormone binding globulin (SHBG). Serum total T was not associated with any of the QUS parameters. Free T and both free and total E-2 were positively related to all QUS readings, while SHBG concentrations were negatively associated. These relationships were observed in both older and younger (< 60 years) men. In a multivariate model, after adjustment for age, centre, height, weight, physical activity levels and smoking, free E-2 and SHBG, though not free T, remained independently associated with the QUS parameters. After further adjustment for IGF-1, however, the association with SHBG became non-significant. Higher free and total E-2 are associated with bone health not only among the elderly but also middle-aged European men.
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| 3. |
- Ward, K. A., et al.
(författare)
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Influence of age and sex steroids on bone density and geometry in middle-aged and elderly European men
- 2011
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Ingår i: Osteoporosis International. - : Springer Science and Business Media LLC. - 1433-2965 .- 0937-941X. ; 22:5, s. 1513-1523
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Tidskriftsartikel (refereegranskat)abstract
- The influence of age and sex steroids on bone density and geometry of the radius was examined in two European Caucasian populations. Age-related change in bone density and geometry was observed. In older men, bioavailable oestradiol may play a role in the maintenance of cortical and trabecular bone mineral density (BMD). To examine the effect of age and sex steroids on bone density and geometry of the radius in two European Caucasian populations. European Caucasian men aged 40-79 years were recruited from population registers in two centres: Manchester (UK) and Leuven (Belgium), for participation in the European Male Ageing Study. Total testosterone (T) and oestradiol (E-2) were measured by mass spectrometry and the free and bioavailable fractions calculated. Peripheral quantitative computed tomography was used to scan the radius at distal (4%) and midshaft (50%) sites. Three hundred thirty-nine men from Manchester and 389 from Leuven, mean ages 60.2 and 60.0 years, respectively, participated. At the 50% radius site, there was a significant decrease with age in cortical BMD, bone mineral content (BMC), cortical thickness, and muscle area, whilst medullary area increased. At the 4% radius site, trabecular and total volumetric BMD declined with age. Increasing bioavailable E-2 (bioE(2)) was associated with increased cortical BMD (50% radius site) and trabecular BMD (4% radius site) in Leuven, but not Manchester, men. This effect was predominantly in those aged 60 years and over. In older Leuven men, bioavailable testosterone (Bio T) was linked with increased cortical BMC, muscle area and SSI (50% radius site) and total area (4% radius site). There is age-related change in bone density and geometry at the midshaft radius in middle-aged and elderly European men. In older men bioE(2) may maintain cortical and trabecular BMD. BioT may influence bone health through associations with muscle mass and bone area.
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| 6. |
- Tajar, Abdelouahid, et al.
(författare)
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Characteristics of Androgen Deficiency in Late-Onset Hypogonadism: Results from the European Male Aging Study (EMAS).
- 2012
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Ingår i: The Journal of clinical endocrinology and metabolism. - : The Endocrine Society. - 1945-7197 .- 0021-972X. ; 97:5, s. 1508-1516
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Tidskriftsartikel (refereegranskat)abstract
- Context:Late-onset hypogonadism (LOH) has been defined as a syndrome in middle-aged and elderly men reporting symptoms in the presence of low testosterone (T). Objective:The objective of the study was to seek objective biochemical and end-organ evidence of androgen deficiency in men classified as having LOH according to our previously published criteria. Design, Setting, and Participants:The design of the study included cross-sectional data from the European Male Aging Study on 2966 community-dwelling men aged 40-79 years in eight European countries. Main Outcome Measure(s):Waist circumference, body mass index, muscle mass, estimated heel bone mineral density (eBMD), hemoglobin, insulin sensitivity, physical activity, metabolic syndrome, insulin resistance index, and cardiovascular disease were measured. Results:Sixty-three men (2.1%) were classified as having LOH: 36 moderate and 27 severe. They were older and more obese than eugonadal men and had, in proportion to the graded T deficiency, lower muscle mass, eBMD, and hemoglobin, with poorer general health. Both moderate and severe LOH was associated with lower hemoglobin, mid-upper arm circumference, eBMD, physical function (measured by the Short Form-36 questionnaire), slower gait speed and poorer general health. Only men with severe LOH showed significant associations with larger waist circumference (β= 1.93cm; 0.04-3.81), insulin resistance (β= 2.81; 1.39-4.23), and the metabolic syndrome (odds ratio 9.94; 2.73-36.22) after adjustments for confounders. Men with low testosterone only (irrespective of symptoms) showed lesser magnitudes of association with the same end points. Conclusions:LOH is associated with multiple end-organ deficits compatible with androgen deficiency. These data support the existence of a syndrome of LOH in only a minority of aging men, especially those with T below 8 nmol/liter.
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| 8. |
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| 9. |
- Fornes, R., et al.
(författare)
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The effect of androgen excess on maternal metabolism, placental function and fetal growth in obese dams
- 2017
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Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 7
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Tidskriftsartikel (refereegranskat)abstract
- Pregnant women with polycystic ovary syndrome (PCOS) are often overweight or obese. To study the effects of maternal androgen excess in obese dams on metabolism, placental function and fetal growth, female C57Bl6J mice were fed a control (CD) or a high fat/high sucrose (HF/HS) diet for 4-10 weeks, and then mated. On gestational day (GD) 15.5-17.5, dams were injected with dihydrotestosterone (CD-DHT, HF/HS-DHT) or a vehicle (CD-Veh, HF/HS-Veh). HF/HS dams had higher fat content, both before mating and on GD18.5, with no difference in glucose homeostasis, whereas the insulin sensitivity was higher in DHT-exposed dams. Compared to the CD groups, the livers from HF/HS dams weighed more on GD18.5, the triglyceride content was higher, and there was a dysregulation of liver enzymes related to lipogenesis and higher mRNA expression of Fitm1. Fetuses from HF/HS-Veh dams had lower liver triglyceride content and mRNA expression of Srebf1c. Maternal DHT exposure, regardless of diet, decreased fetal liver Pparg mRNA expression and increased placental androgen receptor protein expression. Maternal diet-induced obesity, together with androgen excess, affects maternal and fetal liver function as demonstrated by increased triglyceride content and dysfunctional expression of enzymes and transcription factors involved in de novo lipogenesis and fat storage.
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| 10. |
- Huhtaniemi, Ilpo T., et al.
(författare)
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Comparison of serum testosterone and estradiol measurements in 3174 European men using platform immunoassay and mass spectrometry; relevance for the diagnostics in aging men
- 2012
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Ingår i: European Journal of Endocrinology. - 1479-683X. ; 166:6, s. 983-991
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Tidskriftsartikel (refereegranskat)abstract
- Background: The limitations of serum testosterone and estradiol (E-2) measurements using nonextraction platform immunoassays (IAs) are widely recognized. Switching to more specific mass spectrometry (MS)-based methods has been advocated, but directly comparative data on the two methods are scarce. Methods: We compared serum testosterone and E-2 measurements in a large sample of middle-aged/elderly men using a common platform IA and a gas chromatography (GC)-MS method, in order to assess their limitations and advantages, and to diagnose male hypogonadism. Of subjects from the European Male Aging Study (n = 3174; age 40-79 years), peripheral serum testosterone and E-2 were analyzed using established commercial platform IAs (Roche Diagnostics E170) and in-house GC MS methods. Results: Over a broad concentration range, serum testosterone concentration measured by IA and MS showed high correlation (R=0.93, P<0.001), which was less robust in the hypogonadal range (<11 nmol/l; R=0.72, P<0.001). The IA/MS correlation was weaker in E-2 measurements (R=0.32, P<0.001, at E-2 <40.8 pmol/l, and R=0.74, P<0.001, at E-2 >40.8 pmol/l). Using MS as the comparator method, IA ascertained low testosterone compatible with hypogonadism (<11 nmol/l), with 75% sensitivity and 96.3% specificity. The same parameters with IA for the detection of low E-2 (<40.7 pmol/l) were 13.3 and 99.3%, and for high E-2 (>120 pmol/l) 88.4 and 88.6%. Conclusion: A validated platform IA is sufficient to detect subnormal testosterone concentrations in the diagnosis of male hypogonadism. The IA used for E-2 measurements showed poor correlation with MS and may only be suitable for the detection of high E-2 in men.
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