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Monographs of fragrance chemicals and extracts that have caused contact allergy / allergic contact dermatitis
Published in Anton C. de Groot, Monographs in Contact Allergy, 2021
In 2006, in The Netherlands, 52 laundry detergents were investigated for the presence of allergenic fragrances by checking their labels and chemical analyses. Butylphenyl methyl propional was found to be present in 19 of the products (37%) in a concentration range of 8–795 ppm. Butylphenyl methyl propional had rank number 6 (of 15) in the frequency list (25).
Biochemical Aspects of Fatty Liver
Published in Robert G. Meeks, Steadman D. Harrison, Richard J. Bull, Hepatotoxicology, 2020
Among them, some are saturated (hexanal, heptanal, nonanal, decanal, propional, etc.), while others are unsaturated (hexanal, nonenal, decenal, etc.). A special class is formed by the 4-hydroxy-2,3-trans-unsaturated aldehydes, the most represented of which are 4-hydroxy-nonenal, first identified by Benedetti et al. (1982), 4-hydroxy-hexenal, 4-hydroxy-undecenal, and 4-hydroxy-octenal, in magnitude order. Adihydroxy-2,3-trans-unsaturated aldehyde has been also identified as 4,5-dihydroxydecenal.
Barbiturates And Minor Tranquilizers
Published in S.J. Mulé, Henry Brill, Chemical and Biological Aspects of Drug Dependence, 2019
The 2-disubstituted propanediol precursor which is needed for the formation of meprobamate was synthesized by Ludwig and Piech.42 As shown in Figure 5, the precursor was made by a condensation of 2-methyl-valeraldehyde with formaldehyde. The former reactant is synthesized by a two-step reaction from propanal (Figure 5).26 The dicarbamate derivative (meprobamate) was made by reacting the 2-substituted 1, 3-propanediol derivative with phosgene in an inert medium consisting of a tertiary amine acceptor (see Figure 6). This phosgenation process, which was carried out at low temperatures, yields a chlorocarbonate derivative that is ultimately converted to the dicarbamate form. In order to avoid the formation of cyclic carbonates in the reaction vessel, an excess of phosgene must be present.
Ellagic acid attenuates beryllium sulphate-induced oxidative stress and histopathological alterations of spleen in rats
Published in Pharmaceutical Biology, 2022
Yuandi Lei, Tianyi Jiang, Liqin He, Yanping Liu, Zhanbing Sun, Weihua Deng, Lian Huang, Zhaohui Zhang
TBARS, such as malondialdehyde (MDA), lipid hydroperoxides (LOOH), propanal, hexanal, and 4-hydroxynonenal (4-HNE), are the end-product of lipid peroxidation, which causes structural and functional alterations in the cells (Ding et al. 2014). Among these, MDA is the most mutagenic product of lipid peroxidation (Esterbauer et al. 1990) and the level of MDA is used as an indirect biomarker of oxidative stress in tissues (Priyamvada et al. 2008). A previous study reported that EA attenuates doxorubicin-induced testicular injury in rats by reducing the production of MDA (Routray and Ali 2016). Our results showed that administration of EA significantly decreased MDA level in the spleen tissue of BeSO4-intoxicant rats. Decreased levels of MDA indicates the protective effect of EA on lipid peroxidation.
The effect of electronic cigarettes exposure on learning and memory functions: behavioral and molecular analysis
Published in Inhalation Toxicology, 2021
Karem H. Alzoubi, Rahaf M. Batran, Nour A. Al-Sawalha, Omar F. Khabour, Nareg Karaoghlanian, Alan Shihadeh, Thomas Eissenberg
ECIG aerosols have been shown to contain numerous toxicants including aldehydes (Kosmider et al. 2014; Khlystov and Samburova 2016; Sleiman et al. 2016; Ogunwale et al. 2017; Talih et al. 2020), phenols (Chivers et al. 2019; El-Hage et al. 2020), metals (Williams et al. 2017; Olmedo et al. 2018; Zhao et al. 2019), and reactive oxygen species (Bitzer et al. 2017; 2017; Haddad et al. 2019),. ECIG use can lead to harm through inhalation of the stimulant drug nicotine that can cause dependence, leading to increased exposure to the ECIG aerosol. This results in continued inhalation of toxicants that can be formed when PG and VG are heated (e.g. formaldehyde, acetaldehyde, propanal and acrolein; see (El-Hage et al. 2020; El-Hellani et al. 2018)). These aldehydes can lead to lung and heart disease (Ogunwale et al. 2017). ECIG aerosol exposure can also precipitate several harmful effects such as elevated blood pressure and heart rate (Qasim et al. 2017) and stress-induced mitochondrial hyperfusion in stem cells (Zahedi et al. 2019). A recent study showed that chronic exposure to ECIG aerosols, even without nicotine, negatively impacted lipid homeostasis in the airways and impaired immunity (Madison et al. 2019).
Urinary levels of the acrolein conjugates of carnosine are associated with inhaled toxicants
Published in Inhalation Toxicology, 2020
Timothy E. O’Toole, Xiaohong Li, Daniel W. Riggs, David J. Hoetker, Ray Yeager, Pawel Lorkiewicz, Shahid P. Baba, Nigel G. F. Cooper, Aruni Bhatnagar
The measurement of carnosine and its propanal- and propanol-conjugates was accomplished as previously described (Abplanalp et al. 2019). In brief, urine samples were diluted in a solution of 75% acetonitrile:25% water containing 30 nM 13C9 carnosine as an internal standard. Samples were separated and carnosine and its conjugates were identified using a Waters ACQUITY ultra performance liquid chromatography H-Class System (BEH hydrophilic interaction liquid chromatography column equipped with an in-line frit filter unit) coupled with a Xevo TQ-S micro triple quadrupole mass spectrometer. The analytes were eluted using a binary solvent system consisting of 10 mM ammonium formate, 0.125% formic acid in 50% acetonitrile: 50% water for mobile phase A and 10 mM ammonium formate, 0.125% formic acid in 95% acetonitrile: 5% water for mobile phase B at a flow rate of 0.55 mL/min. Initial conditions were 0.1: 99.9 A: B ramping to 99.9: 0.1 A:B over 5 min then quickly ramping to 0.1:99.9 A:B over 0.5 min (Supplemental Figure 1). Aldehyde conjugates were quantified using the peak ratio of histidyl-dipeptide and 13C9 carnosine internal standard, interpolated using a standard curve and expressed as nmole/mg creatinine.