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Central Nervous System Effects of Essential Oil Compounds
Published in K. Hüsnü Can Başer, Gerhard Buchbauer, Handbook of Essential Oils, 2020
Elaine Elisabetsky, Domingos S. Nunes
Geraniol 2 (C10, monoterpene), farnesol 3 (C15, sesquiterpene), and phytol 4 (C20, diterpene) form a good series for structure-activity-mechanism of action comparative studies. These are three primary alcohols with open chains that present an α,β-unsaturation to the carbon that bears the hydroxyl group. All three present an identical unit isopentenol that forms the polar extremity of the chain and identical isoprene units (in 2 and 3) or saturation (4) in the non-polar extremities. The MWs raise in the same sequence (2 < 3 < 4) of their XLogP3, with accompany increases in lipophilicity, whereas the other molecular descriptors remain in the same values.
Emollient Esters and Oils
Published in Randy Schueller, Perry Romanowski, Conditioning Agents for Hair and Skin, 2020
John Carson, Kevin F. Gallagher
The shortest of the branched short-chain alcohols is isopropyl alcohol (IPA). We have already discussed the properties of many of the esters of isopropyl alcohol (Table 6). One point to make is that IPA is a secondary alcohol as opposed to a primary alcohol. The esters of secondary alcohols are generally more stable to hydrolysis than the esters of primary alcohols. Therefore, one would expect to have formulations that are more stable with isopropyl myristate than if they were formulated with ethyl oleate. Indeed, IPM is used in many different formulations without significant hydorlysis and must therefore be considered as providing adequate stability for cosmetic formulation purposes.
Organotin Chemistry
Published in Nate F. Cardarelli, Tin as a Vital Nutrient:, 2019
The systematics of organotin syntheses teach that the most acidic −OH group will react first on esterification. Thus, the carboxylic acid groups should react first, followed by the alcohols. Of these latter functions, the least-crowded primary alcohols should react in preference to the secondary and tertiary types. Within each category the least crowded will react first.
Crosslinking hyaluronic acid soft-tissue fillers: current status and perspectives from an industrial point of view
Published in Expert Review of Medical Devices, 2021
Jimmy Faivre, Amos I. Pigweh, Julien Iehl, Pauline Maffert, Peter Goekjian, François Bourdon
Bisepoxides are a class of chemical crosslinkers for HA in which the epoxide functionalities serve as electrophiles for the Williamson etherification via ring opening [12]. As mentioned earlier, the different bisepoxides used as crosslinkers for HA include BDDE, PEGDE, and DEO. Under strong alkaline conditions (usually at pH 13), bisepoxides react with the hydroxyl groups on the HA chains to form ether linkages as shown in Figure 1 [30]. Generally, temperatures higher than 40°C over a few hours of reaction are reported [31,32]. This leads to the modification of hydroxyl groups at different positions, not necessarily on the primary alcohol [33,34]. The resulting bridge between both HA chains creates an elastic crosslinked HA hydrogel network. Typically, degrees of modification (MoD), commonly measured by 1H NMR, are reported between 1 and 10% for BDDE-crosslinked HA fillers [35,36], the MoD being defined as the molar ratio of crosslinker to HA disaccharide units. This parameter represents the total HA modification, although the crosslinker may be either linked to a single HA strand, or may effectively crosslink two HA chains [36].
Low rates of thiamine prescribing in adult patients with alcohol-related diagnoses in the emergency department
Published in The American Journal of Drug and Alcohol Abuse, 2021
Nathan M. Peck, Theodore C. Bania, Jason Chu
A total of 7,529 patient visits associated with a primary alcohol-related diagnosis were identified. Some subjects had more than one visit and so the denominator for most statistics is not patients, but patient visits. The median age was 44. Woman accounted for 1,782 visits (23.7%). Men accounted for 5,747 visits (76.3%). Thiamine was ordered during 167 (2.2%) patient visits. Thiamine prescription rates for visits during which patients were admitted or had blood drawn are shown in Table 1. For the 167 patient visits during which thiamine was ordered, the associated orders were analyzed by dose and route of administration. For 38 (22.8%) patient visits, 100 mg of thiamine was administered orally. For seven (4.2%) patient visits, 100 mg of thiamine was administered intramuscularly. Thiamine was administered intravenously at a dose of 100 mg in 120 (71.9%) patient visits, 200 mg in 1 (0.6%) patient visit, and 500 mg in 1 (0.6%) patient visit.
Recent developments in predicting CYP-independent metabolism
Published in Drug Metabolism Reviews, 2021
Nikhilesh V. Dhuria, Bianka Haro, Amit Kapadia, Khadjia A. Lobo, Bernice Matusow, Mary A. Schleiff, Christina Tantoy, Jasleen K. Sodhi
The family of alcohol dehydrogenases (ADHs) and aldehyde dehydrogenases (ALDHs) are found abundantly in human liver cytosol and are primarily involved in the conversion of primary alcohols to aldehydes and aldehydes to carboxylic acids via NADP + reduction (Singh et al. 2013; Bhatt et al. 2017; Di et al. 2021). These enzymes are best recognized for their role in the metabolism of ethanol but are also involved in the metabolism of endogenous and exogenous aldehydes to mitigate oxidative stress (Singh et al. 2013), endogenous substrates such as retinol (Napoli 1999), and xenobiotic compounds such as abacavir, hydroxyzine, ethambutol, and felbamate (Foti and Dalvie 2016; Di et al. 2021). Additionally, the in vivo inhibition of ADHs and ALDHs by drugs such as fomepizole, cimetidine, and disulfiram have been demonstrated to result in decreased ethanol metabolism. Thus fomepizole, a nonspecific ADH inhibitor, is commonly used as an antidote for methanol or ethylene glycol (anti-freeze) poisoning (Brent 2009). Meanwhile, the ALDH inhibitor disulfiram is clinically utilized as a deterrent for ethanol consumption, as it prevents ethanol metabolism and results in increased acetaldehyde levels that are associated with myriad unpleasant side effects (Petersen 1992; Chen et al. 2014).