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The Science of Air Pollution
Published in Daniel T. Rogers, Environmental Compliance Handbook, 2023
Benzoylmethylecgonine or cocaine is a stimulant affecting the central nervous system and also acts as an appetite suppressant. Antibiotics inhibit the growth of bacteria. Sildenafil citrate is an arterial stimulant that was originally intended to treat high blood pressure (Barnes et al. 2008). Testosterone is a male sex hormone—an anabolic steroid—and affects the growth of muscle mass. Other emerging contaminants of note include a group of compounds called perchlorates and the compound 1,4-Dioxane. Perchlorates are colorless and odorless salts. They are a group of compounds including: Magnesium perchlorate (MgClO4)Potassium perchlorate (KClO4)Ammonium perchlorate (NH4ClO4)Sodium perchlorate (NaClO4)Lithium perchlorate (LiClO4)
Macrocyclic Receptors for Biomolecules and Biochemical Sensing
Published in Satish Kumar, Priya Ranjan Sahoo, Violet Rajeshwari Macwan, Jaspreet Kaur, Mukesh, Rachana Sahney, Macrocyclic Receptors for Environmental and Biosensing Applications, 2022
Satish Kumar, Priya Ranjan Sahoo, Violet Rajeshwari Macwan, Jaspreet Kaur, Mukesh, Rachana Sahney
Most molecular recognition studies were initially conducted on steroids. Steroids are oxidative derivatives of sterols containing four fused rings, three with six carbons and one with five rings. The steroid nucleus is almost planar and is relatively rigid; the fused rings do not allow rotation about C–C bonds. Breslow and co-workers (Breslow and Zhang 1996) synthesized cyclodextrin dimers linked to each other by different spacer units which can bind to hydrophobic molecules like sterols. Complexation studies between dimeric cyclodextrin derivative 18 and cholesterol (Fig. 7.22) were studied using the solubility technique. The binding constant was found to be 200–300 times greater than monomeric β-cyclodextrins. The strong complexation could be observed due to the ability of the two cyclodextrin rings to align correctly around the cholesterol molecule for cooperative binding in between. This strategy of complexation can be used to increase the solubility of steroids, which are sparingly soluble in water and used as pharmaceutical compounds. Various other container type molecules like calixarenes, cyclophanes and cucurbituril have also shown complexation behavior with cholesterol and other hydrophobic guest used in pharmaceutical applications. An outline of complexation strategy with different steroid molecules is reviewed (Hishiya et al. 1999; Schneider et al. 2013).
Enzyme Catalysis
Published in Harvey W. Blanch, Douglas S. Clark, Biochemical Engineering, 1997
Harvey W. Blanch, Douglas S. Clark
Steroids have been employed for the treatment of inflamatory diseases since the late 1940 's. The sources of steroids are plant and animal tissues, and most steroids are derived by either chemical or microbial conversion of starting materials, typically phytosterols, such as diosgenin and stigmasterol. Diosgenin is obtained from the root of the barbasco plant, grown in Mexico and Central America; stigmasterol is obtained from soybean seed oil. Diosgenin is a starting material in the formation of pregnenolone, and stigmasterol is the precursor for progesterone. The 3 -one-4-ene A-ring of corticosteriods can be obtained from pregnenolone which is converted to progesterone. The most therapeutically important steroids (cortisone, hydrocortisone, prednisone, prednisolone etc) have an 11 -hydroxyl or 11 -keto function, in addition to a 17 a-hydroxyl function. The ring numbering system of steroids and the carbon numbering scheme are illustrated in Figure 8.6.
The effect of sex hormones on skeletal muscle adaptation in females
Published in European Journal of Sport Science, 2022
Sarah E. Alexander, Alexander C. Pollock, Séverine Lamon
Sex steroids (also known as gonadocorticoids, and commonly referred to as sex hormones) are steroid hormones produced by the gonads, adrenal glands and a number of peripheral tissues. These hormones play an integral role in the development of primary and secondary sex characteristics and the maintenance of the reproductive system (Widmaier, Raff, & Strang, 2014). All sex steroids share the same chemical backbone, which is the product of a common biosynthesis pathway stemming from cholesterol. According to their number of carbon atoms, they can be classified into androgens (19C), estrogens (18C) and progestogens (21C). Sex hormones bind to their specific receptors located at the surface of the cell membrane and/or in the nucleus. Upon ligand binding, these receptors trigger a multitude of molecular signalling cascades, allowing sex steroids to exert their effects on their target tissues, including skeletal muscle (Ekenros, Papoutsi, Friden, Dahlman Wright, & Linden Hirschberg, 2017). Skeletal muscle is one of the main tissues that underpin sex-based differences in humans. Skeletal muscle has the second highest number of genes (up to 3000) that are differentially expressed between males and females (Oliva et al., 2020), leading to sex-specific structural and functional differences. These differences are driven, in part, by varying concentrations of sex hormones.
Perfectionism and attitudes towards doping in athletes: A continuously cumulating meta-analysis and test of the 2 × 2 model
Published in European Journal of Sport Science, 2020
Daniel J. Madigan, Sarah H. Mallinson-Howard, Michael C. Grugan, Andrew P. Hill
Doping is defined as the use of a substance (e.g. anabolic androgenic steroids) or method (e.g. blood doping) that is prohibited by the World Anti-Doping Agency (WADA, 2018). Doping is banned because it contravenes open and fair competition (White Paper on Sport, 2007). There are also additional health risks associated with doping that make its prohibition justifiable. For example, anabolic androgenic steroid use is linked with increased risk of liver damage, heart failure (Bird, Goebel, Burke, & Greaves, 2016), and even suicide (Lindqvist et al., 2013). Importantly, doping is not isolated to elite athletes with evidence suggesting that this is also an issue among amateur, adolescent, and university athletes (e.g. Nicholls, Cope, et al., 2017). It is not surprising, then, that researchers have called for an increased focus on education aimed at discouraging athletes from all sports, levels, and ages from doping (e.g. Backhouse, Patterson, & McKenna, 2012).
Environmental impact and biological removal processes of pharmaceutically active compounds: The particular case of sulfonamides, anticonvulsants and steroid estrogens
Published in Critical Reviews in Environmental Science and Technology, 2020
Cristiano S. Leal, Daniela P. Mesquita, António Luís Amaral, Almerinda M. Amaral, Eugénio C. Ferreira
Steroid hormones are a group of biologically active compounds synthesized from cholesterol and with a common cyclopentane-perhydro phenanthrene ring (Ying, Kookana, & Ru, 2002). Four of the estrogens most commonly found in wastewater include 3 natural steroids (17β-estradiol (E2), estrone (E1) and estriol (E3)) and one synthetic compound (17α-ethinylestradiol (EE2)) (Racz & Goel, 2010). E2 is a naturally occurring steroid hormone, being the major female sex hormone, and is essential factor in the regulation of the menstrual cycle, in the development of puberty and in secondary female sex characteristics. E2 can also be present in hormone therapy products, such as reduced estrogen production (menopausal and peri-menopausal symptoms), treatment of hypoestrogenism, palliative treatment of breast and prostate cancer, as well as for transgender hormone therapy (Drugbank, 2016c). EE2 is used mainly for the treatment of vasomotor symptoms associated with the menopause, female hypogonadism, prostatic carcinoma-palliative therapy, treatment of breast cancer, and contraceptive purposes (Drugbank, 2016d).