Depending on the number and character of their functional groups, steroid molecules may show diverse reactivities. Moreover, the reactivity of a functional group varies according to its location within the molecule (for example, esters are formed readily by 3-OH groups but only with difficulty by the 11β-OH group). An important property of steroids is polarity —., their solubility in oxygen-containing solvents (., water and alcohols ) rather than hydrocarbon solvents (., hexane and benzene ). Hydroxyl, ketonic, or ionizable (capable of dissociating to form electrically charged particles) groups in a steroid molecule increase its polarity to an extent that is strongly influenced by the spatial arrangement of the atoms within the molecule.
The most common side effect of topical corticosteroid use is skin atrophy. All topical steroids can induce atrophy, but higher potency steroids, occlusion, thinner skin, and older patient age increase the risk. The face, the backs of the hands, and intertriginous areas are particularly susceptible. Resolution often occurs after discontinuing use of these agents, but it may take months. Concurrent use of topical tretinoin (Retin-A) % may reduce the incidence of atrophy from chronic steroid applications. 30 Other side effects from topical steroids include permanent dermal atrophy, telangiectasia, and striae.
Beth maybe based upon today's standards……but I am talking about our biologic standards. Most people reading this are coming to the understanding from their own perception of what fat really is. Leptin became biologically important from an evolutionary standpoint because food was scarce more often then not and most humans had to protect against low leptin levels not high one like we see today. The paradox in this system and why people get confused is that ultra low leptin and ultra high leptin biochemically cause high US CRPs and this shuts down the thyroid. It is protective in food shortage for survival and it kills you with chronic excess due to chronic elevations of cortisol and insulin simultaneously present in the cellular terroir (levee one). This induces mRNA at the DNA level that up-regulates genes that no longer allow p53 gene to protect our genome from oncogenesis. (levee 16)