In order to examine whether plasma samples may be used for steroid analysis after long periods of storage, cortisol, testosterone, oestrone and oestradiol were remeasured in samples, which had been analysed 1.3-10.8 years earlier. The method for the measurement of these steroids was unchanged over this period. The results demonstrate that at a temperature of -25 degrees C steroids remained stable. Only cortisol and testosterone concentrations showed a small, insignificant decrease (6-9%) after 3 to 4 years of storage. These differences are well within the range of the precision of the method (interassay variation), which over a period of 11 years was 9.4%, 8.0%, 10.0% and 9.5% for cortisol, testosterone, oestrone and oestradiol, respectively. It is concluded that steroid hormones in human plasma are stable in our laboratory, and that they might be analysed even after more than 10 years of storage at -25 degrees C.
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Psychoneuroendocrinology
January 2025
Department of Psychology, Bangor University, Bangor, Gwynedd, United Kingdom. Electronic address:
In a variety of settings, cortisol and testosterone are positively "coupled." That is, within-person fluctuations of these hormones occur in parallel, with increases and decreases in one hormone corresponding to increases and decreases in the other. A dataset comprised of salivary cortisol and testosterone levels from varsity women athletes from six different Emory University sports teams (volleyball 2002, 2005, and 2008; softball 2004; tennis 2009; soccer 2013) was used to explore the relationship between coupling and hormone reactivity to athletic competition.
View Article and Find Full Text PDFPhysiol Behav
January 2025
Military Nutrition Division, United States Army Research Institute of Environmental Medicine, Natick, MA, USA. Electronic address:
The mentally and physically challenging 19-20 day, multi-stressor US Army Special Forces Assessment and Selection (SFAS) course selects soldiers for Army Special Forces (SF) training. If selected, candidates enroll for advanced training in the 2-year Special Forces Qualification Course (SFQC) to qualify for the SF. This longitudinal study examined physiological, psychological, and nutritional status of soldiers before (pre-SFAS) and after SFAS (post-SFAS), and post-SFQC, to identify predictors of graduation from SFQC.
View Article and Find Full Text PDFProg Neuropsychopharmacol Biol Psychiatry
January 2025
Department of Psychotherapy and Psychosomatic Medicine, Faculty of Medicine, Technische Universität Dresden, Dresden, Germany. Electronic address:
Background: After the birth of a child, also fathers may develop postpartum depression. Altered steroid hormone concentrations are discussed as a possible underlying mechanism, as these have been associated with depressive symptoms in previous studies outside the postpartum period. While higher paternal testosterone levels have been found to protect against paternal postpartum depressive symptoms (PPDS), an association between higher cortisol levels and PPDS has been seen in postpartum mothers, with no comparable studies available on fathers.
View Article and Find Full Text PDFFish Physiol Biochem
January 2025
Fish Nutrition, Biochemistry and Physiology Division, ICAR-Central Institute of Fisheries Education, Versova, Andheri West, Mumbai, 400061, Maharashtra, India.
A 60-day feeding trial was conducted to evaluate the combined effect of dietary soy phytoestrogens, specifically genistein and daidzein, on the gonadal recrudescence and maturation of male Cyprinus carpio (Linnaeus, 1758). Adult male C. carpio (60 ± 10 g) were fed with a diet with no added genistein or daidzein (C), 110 mg/100 mg genistein (GL), 210 mg/100 g genistein (GH), 4 mg/100 g daidzein (DL), 8 mg/100 g daidzein (DH), combination of 110 mg/100 mg genistein and 4 mg/100 g daidzein (DGL, equivalent to 17.
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