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284998

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Robert W Huigens et al.
Nature chemistry, 5(3), 195-202 (2013-02-21)
High-throughput screening is the dominant method used to identify lead compounds in drug discovery. As such, the makeup of screening libraries largely dictates the biological targets that can be modulated and the therapeutics that can be developed. Unfortunately, most compound-screening...
Yogan Khatri et al.
Chembiochem : a European journal of chemical biology, 17(1), 90-101 (2015-10-21)
Cytochromes P450 catalyze a variety of synthetically useful reactions. However, it is difficult to determine their physiological or artificial functions when a plethora of orphan P450 systems are present in a genome. CYP260A1 from Sorangium cellulosum So ce56 is a new...
Esther Leal et al.
Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology, 179(1), 77-86 (2008-08-19)
This study was conducted to test the sensitivity to gonadal steroids of the systems regulating food intake in sea bass. Animals were treated with silastic implants containing 17-beta-estradiol or testosterone. Self-feeding was recorded for 31 days using computerized demand feeders...
P M Lokman et al.
Steroids, 62(10), 655-658 (1997-11-05)
Despite the existence of several protocols, problems appear to persist in the small scale chemical synthesis of radiolabeled 11-ketotestosterone from cortisol. We investigated the possibilities of using the mild oxidant pyridinium dichromate for the oxidative cleavage of the dihydroxyacetone side...
Hiroshi Suzuki et al.
The Journal of steroid biochemistry and molecular biology, 198, 105550-105550 (2019-11-30)
The production of 11-ketotestosterone (11KT), an important steroid hormone in piscine spermatogenesis, is regulated by the pituitary gonadotropins [Gths: follicle-stimulating hormone (Fsh) and luteinizing hormone (Lh)] and it is synthesized by catalytic reactions involving several steroidogenic enzymes. Among these enzymes...
I Mayer et al.
General and comparative endocrinology, 79(1), 23-30 (1990-07-01)
The seasonal changes in plasma levels of the androgens 11-ketotestosterone (OT), testosterone (T), 11 beta-hydroxytestosterone (OHT), 11-ketoandrostenedione (OA), and 11 beta-hydroxyandrostenedione (OHA) were measured in the male three-spined stickleback (Gasterosteus aculeatus L). OT was the dominant plasma androgen in the...
Ignasi Forné et al.
Proteomics, 9(8), 2171-2181 (2009-03-27)
In the farmed flatfish Senegalese sole, F1 males reared in captivity often show lower sperm production and fertilization capacity than wild-caught males. To gain insights into the molecular mechanisms that may be altered in the F1 testis, we used 2-D...
Lance Brooker et al.
Drug testing and analysis, 1(11-12), 587-595 (2010-04-01)
Adrenosterone (androst-4-ene-3,11,17-trione, 11-oxoandrostenedione) is an endogenous steroid hormone that has been promoted as a dietary supplement capable of reducing body fat and increasing muscle mass. It is proposed that adrenosterone may function as an inhibitor of the 11beta-hydroxysteroid dehydrogenase type...
I Mayer et al.
Hormones and behavior, 28(2), 181-190 (1994-06-01)
The onset of spawning behavior in male salmonids can be closely correlated to circulating levels of the progestin 17 alpha,20 beta-dihydroxy-4-pregnen-3-one (20-P). However, evidence that 20-P plays a causal role in the development and maintenance of spawning behavior in male...
Maria J Agulleiro et al.
Comparative biochemistry and physiology. Part A, Molecular & integrative physiology, 147(4), 885-892 (2007-03-16)
The effect of 11-ketoandrostenedione (OA) on plasma concentrations of sexual steroids and spermatogenesis of Senegalese sole (Solea senegalensis) implanted with gonadotropin-releasing hormone agonist (GnRHa) was investigated. Males were treated with saline (control) or with GnRHa implants (50 mug kg(-1)) in...
P P de Waal et al.
Reproduction (Cambridge, England), 136(2), 225-234 (2008-05-13)
The biological activity of androgens, important for male sexual differentiation and development, is mediated by the androgen receptor (AR) that binds to specific DNA recognition sites regulating the transcription of androgen target genes. We investigated androgen production by adult zebrafish...
C A Manire et al.
The Journal of experimental zoology, 284(5), 595-603 (1999-09-02)
Previous studies in the placental viviparous bonnethead shark, Sphyrna tiburo, have correlated 17 beta-estradiol, progesterone, testosterone, and dihydrotestosterone with reproductive events in both males and females. However, several key reproductive events, including implantation, maintenance of pregnancy, and parturition, did not...
Ewa Kozłowska et al.
Microbial cell factories, 17(1), 71-71 (2018-05-14)
Steroid compounds are very interesting substrates for biotransformation due to their high biological activity and a high number of inactivated carbons which make chemical modification difficult. Microbial transformation can involve reactions which are complicated and uneconomical in chemical synthesis, and...
Anna Hellqvist et al.
General and comparative endocrinology, 158(2), 178-182 (2008-07-31)
In many animals, including the three-spine stickleback (Gasterosteus aculeatus), photoperiod strongly influences reproduction. The aim of this study was to investigate if feedback mechanisms on the brain-pituitary-gonadal axis play a role in mediating the photoperiodic response in the stickleback. To...
Jia Zheng et al.
The lancet. Diabetes & endocrinology, 8(8), 693-702 (2020-07-25)
Although clinicians often measure the serum concentration of androgens in premenopausal women presenting with sexual dysfunction, with some women given testosterone or dehydroepiandrosterone as treatment if their concentrations are low, whether androgens are determinants of sexual function in women of...
I Mayer et al.
General and comparative endocrinology, 82(1), 86-92 (1991-04-01)
Brain homogenates from male Atlantic salmon parr aromatized tritiated androstenedione to estrogens. The aromatase activity in homogenates of whole brains from castrated male parr was lower than that in homogenates from sham-operated male parr in autumn. This was also found...
Wei Wang et al.
Frontiers in endocrinology, 11, 115-115 (2020-04-10)
11-ketotestosterone (11-KT) is a non-aromatizable and the most potent androgen in a few teleost. It has been reported that 11-KT in serum had a high concentration and increased sharply before the period of yolk deposition in females of few fishes....
H J Th Goos et al.
Molecular and cellular endocrinology, 197(1-2), 105-116 (2002-11-15)
This paper reviews a series of recent studies on the effect of adaptation to chronic stress on pubertal development in the common carp. In pre-pubertal male common carp adaptation to temperature stress caused a retardation of testicular development. Stress-induced delay...
I Mayer et al.
General and comparative endocrinology, 77(1), 70-74 (1990-01-01)
Blood cells from Baltic salmon, Salmo salar, three-spined stickleback, Gasterosteus aculeatus, eel pout, Zoarces viviparus, crucian carp, Carassius carassius, African catfish, Clarias gariepinus, and reedfish, Calamoichthys calabaricus, were incubated with tritiated 11 beta-hydroxyandrostenedione (OHA) or 11-ketoandrostenedione (OA). In all fish...
René Ullrich et al.
Journal of inorganic biochemistry, 183, 84-93 (2018-04-01)
Two unspecific peroxygenases (UPO, EC 1.11.2.1) from the basidiomycetous fungi Marasmius rotula and Marasmius wettsteinii oxidized steroids with hydroxyacetyl and hydroxyl functionalities at C17 - such as cortisone, Reichstein's substance S and prednisone - via stepwise oxygenation and final fission...
Yi Ta Shao et al.
PloS one, 9(6), e100330-e100330 (2014-06-26)
Optomotor studies have shown that three-spined sticklebacks (Gasterosteus aculeatus) are more sensitive to red during summer than winter, which may be related to the need to detect the red breeding colour of males. This study aimed to determine whether this...
Joachim Kurtz et al.
The American naturalist, 170(4), 509-519 (2007-09-25)
The immunocompetence handicap hypothesis (ICHH) provides a functional explanation for how sexual ornaments can provide honest signals of male quality. A key aspect of this hypothesis is that testosterone (T) has a bimodal effect: a higher T level enhances the...
I Mayer et al.
General and comparative endocrinology, 109(2), 223-231 (1998-02-25)
Somatolactin (SL) is a hormone recently isolated and characterized from fish pituitaries. Although the functions of SL are still largely unknown, it has been implicated in reproduction. In this study, the effects of gonadal steroids on SL secretion were investigated...
B Charpentier et al.
Steroids, 52(5-6), 609-621 (1988-11-01)
As part of a search for derivatives designed to conjugate to amino groups, either of a protein carrier for antibody production or of an immobilized side-chain on a polymer for affinity chromatography, functionalized estrone and estradiol analogues were prepared. These...
Joji Nakayama et al.
Molecular cancer research : MCR, 18(3), 477-487 (2019-11-22)
Metastasis of cancer cells is multi-step process and dissemination is an initial step. Here we report a tamoxifen-controllable Twist1a-ERT2 transgenic zebrafish line as a new animal model for metastasis research, and demonstrate that this model can serve as a novel...
Miklós K Páll et al.
Hormones and behavior, 42(3), 337-344 (2002-12-04)
Courtship declines and ceases while parental care increases in the presence of developing eggs during the nesting cycle of the male three-spined stickleback, Gasterosteus aculeatus. Furthermore, circulating 11-ketotestosterone (11KT) levels are higher during the initial "courtship phase" than during the...
Syed Ghulam Musharraf et al.
Steroids, 78(2), 171-181 (2012-11-20)
Electrospray ionization tandem mass spectrometry (ESI-MS/MS) was used to investigate the effect of different substitutions introduced during metabolism on fragmentation patterns of four anabolic steroids including methyltestosterone, methandrostenolone, cis-androsterone and adrenosterone, along with their metabolites. Collision-induced dissociation (CID) analysis was...
B Borg et al.
Biology of reproduction, 58(3), 814-820 (1998-03-25)
The aim of the present study was to clarify the role of feedback control on the (brain)-pituitary-gonadal axis in regulating FSH (gonadotropic hormone, GTH I) and LH (GTH II) in natural maturation in salmonids. In two experiments, 2-yr-old previously mature...
M Numazawa et al.
Journal of steroid biochemistry, 28(3), 337-344 (1987-09-01)
The metabolism of 4-androstene-3,6,17-trione (AT), previously described as a suicide substrate for aromatase, and its irreversible binding to aromatase were studied by using human placental microsomes. AT was rapidly converted into 3 beta-reduced metabolite (3-OHAT) with an enzyme other than...
Lance Brooker et al.
Drug testing and analysis, 4(12), 951-961 (2012-09-19)
Glucocorticoids are listed on the World Anti-Doping Agency (WADA) Prohibited List of substances. The detection of the administration of hydrocortisone and cortisone is complicated by the fact that the human body also produces these steroids naturally. Gas chromatography-combustion-isotope ratio mass...
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