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Sperm concentration is an essential parameter in the diagnostic evaluation of men from infertile couples. It is usually determined by manual counting using a hemocytometer, and is therefore both laborious and subjective. We have earlier shown that a newly developed image cytometry (IC) method may be used to determine sperm concentration. Here we present a validation of the IC method by analysis of 4010 semen samples. There was high agreement between IC and manual counting at sperm concentrations above 3 mill/ml and in samples with concentrations above 12 mill/ml the two methods can be used interchangeable. However, we found substantial differences in samples below 3 mill/ml. We also assessed the accuracy of the two methods by repeated measurements of 248 samples, which revealed that IC measurements seemed more accurate. Moreover, based on ten samples counted by several operators the IC method had a lower coefficient of variation than the manual method (5% vs 10%), indicating a better precision of the IC method. In conclusion, measurement of sperm concentration by IC can be used at concentrations above 3 mill/ml and seems more accurate and precise than manual counting, making it an attractive option in the daily clinical practice. [ABSTRACT FROM AUTHOR]

Objectives: This study tested whether genetic variation in the CETP gene is consistent with a protective effect of cholesteryl ester transfer protein (CETP) inhibition on risk of ischemic events and on total mortality, without the adverse effects reported for torcetrapib. Background: Torcetrapib, an inhibitor of CETP, increased risk of death and ischemic cardiovascular disease of those randomized to the drug, despite improving the lipid profile. Methods: The Copenhagen City Heart Study is a prospective cohort study of 10,261 individuals, aged 20 to 93 years, who were followed for up to 34 years (1976 to 2010). Of these, 2,087 developed ischemic heart disease, 1,064 developed ischemic cerebrovascular disease, and 3,807 died during follow-up. We selected 2 common genetic variants in CETP previously associated with reductions in CETP activity, thus mimicking the effect of pharmacological CETP inhibition. Results: In individuals carrying 4 versus 0 high-density lipoprotein cholesterol–increasing alleles, there was an increase in levels of high-density lipoprotein cholesterol of up to 14% (0.2 mmol/l), and concomitant decreases in triglycerides, low-density lipoprotein cholesterol, and non–high-density lipoprotein cholesterol of, respectively, 6% (0.1 mmol/l), 3% (0.1 mmol/l), and 4% (0.2 mmol/l) (p for trend 0.004 to <0.001). Corresponding hazard ratios were 0.76 (95% confidence interval [CI]: 0.68 to 0.85) for any ischemic vascular event, 0.74 (95% CI: 0.65 to 0.85) for ischemic heart disease, 0.65 (95% CI: 0.54 to 0.79) for myocardial infarction, 0.77 (95% CI: 0.65 to 0.93) for ischemic cerebrovascular disease, 0.71 (95% CI: 0.58 to 0.88) for ischemic stroke, and 0.88 (95% CI: 0.80 to 0.97) for total mortality. CETP genotypes did not associate with variation in markers of possible side effects previously reported for torcetrapib. Conclusions: Genetic CETP inhibition associates with reductions in risk of ischemic heart disease, myocardial infarction, ischemic cerebrovascular disease, and ischemic stroke, with a corresponding antiatherogenic lipid profile, and with increased longevity, without adverse effects. [Copyright &y& Elsevier]

Clinical proteomics aims to deliver cost-effective multiplexing of potentially hundreds of diagnostic proteins, including distinct protein isoforms. The analytical strategy known as targeted proteomics is particularly promising because it is compatible with robust mass spectrometry (MS)-platforms already implemented in many clinical laboratories for routine quantitation of small molecules (i.e. uHPLC coupled to triple-quadrupole MS). Progress in targeted proteomics of circulating insulin-like growth factor 1 (IGF-I) have provided valuable insights about tryptic peptides, transitions, internal standards and calibrants. The present challenge is to examine if targeted proteomics of IGF-I can truly measure up to the routine performance that must be expected from a clinical testing platform. [ABSTRACT FROM AUTHOR]

An isotope-dilution TurboFlow-LC-MS/MS method for simultaneous quantification of the ten steroid metabolites dehydroepiandrosterone sulfate (DHEAS), progesterone, 17α-hydroxyprogesterone (17-OHP), Δ4-androstenedione (Adione), corticosterone, 11-deoxycortisol, cortisol, cortisone, testosterone (T), and estrone 3-sulfate (E1-S) in serum was developed and validated. Limits of quantification, variability (inter- and intra-day), analytical range and linearity were all found to be acceptable for clinical use. Furthermore, sample stability was evaluated including the influence of freeze-thaw cycles and the effects of temperature and storage time. The method was applied to 391 serum samples from healthy, Danish boys 10–18 years old. The concentration ranges of the included steroid metabolites for this population are presented. Concentrations of DHEAS, 17-OHP, Adione and T in the 391 serum samples were furthermore compared to results obtained using an existing LC-MS/MS method in our laboratory. Excellent agreement was found between the methods. Furthermore, the improved sensitivity of the new method allowed for quantification of a number of samples found to be below the LOQs of the existing method. Thus, the two instruments and their associated methods were validated as possible back-ups for each other, which we consider an extremely important issue in high-throughput laboratories analyzing clinical samples on a regular basis. The ten analytes included can be analyzed simultaneously but it is also possible only to include some of these analytes for specific diagnostic purposes which make the new method an extremely useful tool in the clinical laboratory. [ABSTRACT FROM AUTHOR]

Self-reported psychological stress has been associated with decreased semen quality. Cortisol levels in scalp hair (hair cortisol concentration, HCC) has emerged as a potential objective marker of psychological stress. Thus, we investigated if HCC was associated with markers of testicular function. Furthermore, we examined whether three common single nucleotide polymorphisms in the glucocorticoid-receptor gene (NR3C1 , chromosome 5), potentially affecting receptor sensitivity, were associated with HCC and could influence the studied association between HCC and testicular function. Cross-sectional study. We analysed HCC, serum-levels of reproductive hormones, semen parameters, and the three NR3C1- polymorphisms; Bcl I (rs41423247), Tth111 I (rs10052957), and 9β (rs6198), in a population of 696 men from the general population. HCC was not associated with testicular function, and adjustment for the three NR3C1- polymorphisms did not alter the results. However, HCC increased significantly with the number of Tth111 I minor-alleles (T) and decreased significantly with the number of 9β minor-alleles (G). Given previously shown associations between stress and semen quality, and that no association between HCC and self-reported stress was observed in the current study, we speculate that negative reproductive effects of stress may not be mediated directly by cortisol. This study demonstrates associations between HCC and glucocorticoid receptor gene variants indicating that these SNPs may influence systemic glucocorticoid levels, but the potential health effects of such alterations are yet unknown. • Psychological stress has been shown to be associated with impaired semen quality. • Hair cortisol, a potential stress marker, was not associated with testis function. • Adjustment for the Bcl I, Tth111 I, and 9β NR3C1 SNPs did not influence the results. • The Tth111 I and the 9β SNPs were associated with hair cortisol. [ABSTRACT FROM AUTHOR]

Adrenarche is characterized by steadily rising levels of adrenal androgen metabolites from 4–6 years of age. We recently described marked gender-specific differences in circulating ratios between selected adrenal androgen metabolites in a cross-sectional study. This may suggest gender differences in steroidogenic enzyme activities. We therefore aimed at verifying these findings in a prospective, longitudinal study of healthy boys and girls who were examined during pubertal transition. A longitudinal study of 20 healthy children from the COPENHAGEN Puberty Study, followed every 6 months for 5 years. Clinical examinations were conducted and serum concentrations of Androstenedione (Adione), 17-hydroxyprogesterone (17-OHP), testosterone (T), dehydroepiandrosterone (DHEA) and DHEA sulfate (DHEAS) were quantified by a newly developed LC-MS/MS method. DHEA, DHEAS, Adione, 17-OHP and T increase with age. Boys had higher levels of DHEAS from 10.5 years of age, whereas girls had higher levels of Adione from 13 years of age compared to boys. Interestingly, we observed significantly higher ratios of DHEAS/DHEA (sulfotransferase activity) in boys before and after pubertal onset compared to girls, whereas Adione/17-OHP (CYP 17 activity) appeared to increase more in pubertal girls compared to boys. This suggests that adrenal steroidogenic enzyme activities show developmental as well as gender-specific changes in healthy children. [ABSTRACT FROM AUTHOR]

The influence of sex, age, pubertal development and oral contraceptives on dehydroepiandrosterone (DHEA), DHEA sulfate (DHEAS), 17α-hydroxyprogesterone (17-OHP), Δ4-androstenedione (Adione), testosterone (T), calculated free testosterone (fT), free androgen index (FAI) and selected ratios in 1798 serum samples from healthy children, adolescents and young adults was evaluated. Samples were analyzed by Turboflow-LC–MS/MS. Sex hormone-binding globulin was analyzed by immunoassay. All steroid metabolite concentrations were positively associated with age and pubertal development in both sexes and generally higher in males than in females except for Adione. The pubertal rise in T in males was more pronounced compared to females, reflecting contribution from the testes. Ratios between steroid metabolites varied and depended on sex and age. All ratios were lower during infancy compared to later in life. Use of oral contraceptives significantly lowered serum concentrations of all steroid metabolites, fT, FAI, the 17-OHP/Adione, the Adione/T and the DHEA/Adione ratios, but not the DHEA/DHEAS ratio. We provide reference ranges for DHEA, DHEAS, 17-OHP, Adione, T, fT, FAI and selected ratios in relation to sex, age and pubertal development. Use of oral contraceptives strongly influences adrenal steroidogenesis and should be considered when diagnosing and monitoring treatment of patients with disorders of sex development. [ABSTRACT FROM AUTHOR]

Parabens are added to personal care products as antimicrobial preservatives. They have been suggested to have endocrine disrupting abilities. Prenatal exposure to parabens has been associated with reproductive endpoints including reduced male anogenital distance (AGD, distance from anus to genitals), which is sensitive to prenatal anti-androgenic exposure. To study the associations between maternal paraben concentrations in second trimester urine and AGD and reproductive hormone concentrations at 3 months of age in offspring. Pregnant women from Odense, Denmark were included in early pregnancy from 2010 to 12, and their children are being followed up. Fasting spot urine samples from 536 pregnant women were analyzed for methylparaben (MeP), ethyl-paraben (EtP), iso-propylparaben (i-PrP), n-propylparaben (n-PrP), n-butylparaben (n-BuP) and benzylparaben (BzP) by liquid chromatography tandem mass spectrometry and thereafter osmolarity adjusted. Three months after expected date of birth, AGD was measured in 452 children, and serum concentrations of follicle stimulating hormone (FSH), luteinizing (LH), testosterone, dehydroepiandrosterone-sulphate (DHEAS), androstenedione and 17-hydroxyprogesterone (17-OHP) were measured in 198 children. Maternal paraben exposure was categorized into tertiles or below and above level of detection, and sex-stratified multiple linear regression analyses were performed with AGD or reproductive hormones as outcomes. Most pregnant women had low concentrations of parabens in urine, but 10% exceeded the threshold for adverse estrogenic effects. Higher maternal paraben exposure was associated with shorter AGD in male offspring and longer AGD in girls, although only significant for MeP in boys. In addition, FSH, LH, DHEAS, 17-OHP concentrations were lower in girls with high prenatal paraben exposure, whereas no consistent pattern was found in boys. The endocrine disrupting abilities of parabens may affect humans at vulnerable time periods during development, which may have long term impact on reproductive function. This is the first study to find these associations in girls and our findings need confirmation. Unlabelled Image • Parabens are antimicrobial preservatives and suggested to have endocrine disrupting abilities. • Among 536 Danish pregnant women paraben in urine were low, but 10.4% exceeded the threshold for adverse estrogenic effects. • Higher maternal paraben exposure was associated with shorter anogenital distance (AGD) in boys and longer AGD in girls. • Sex hormone concentrations were lower in girls with high prenatal paraben exposure. • Prabens may affect humans at vulnerable time periods during development. [ABSTRACT FROM AUTHOR]