The most common cholesterol and phytosterol oxidation products found in foodstuffs or biological matrices are the 7alpha- and 7beta-hydroxysterol, 7-ketosterol, 5alpha,6alpha- and 5beta,6beta-epoxysterol, and triol derivatives of sterols. This study focused on the preparation and purification of such products derived from campesterol, stigmasterol and beta-sitosterol. The identity of the substances was confirmed by mass spectroscopic analysis. The elution order of a complex mixture composed of the 7alpha- and 7beta-hydroxysterol, 7-ketosterol, 5alpha,6alpha- and 5beta,6beta-epoxysterol, and triol derivatives of cholesterol, campesterol, stigmasterol and beta-sitosterol was recorded on an apolar as well as a medium-polarity capillary column in relation to two commonly used internal standards, i.e. alpha-cholestane and 19-hydroxy cholesterol. Flame-ionization detector as well as mass spectrometry response factors were derived from a gravimetrically prepared mixture of commercially available cholesterol oxide standards. It was proven that the ionization efficiency of cholesterol and phytosterol oxides are very similar and that response factors obtained for cholesterol oxidation products are also valid for quantitative work regarding phytosterol oxidation products.
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http://dx.doi.org/10.1016/j.chroma.2004.08.123 | DOI Listing |
iScience
January 2025
Laboratory of Functional Molecules and Materials, School of Physics and Optoelectronic Engineering, Shandong University of Technology, 266 Xincun Xi road, Zibo 255000, P.R. China.
In recent years, photocatalytic materials with a nanofiber-like morphology have garnered a surge of academic attention due to their distinctive properties, including an expansive specific surface area, a considerable high aspect ratio, a pronounced resistance to agglomeration, superior electron survivability, and robust surface activity. Consequently, the synthesis of photocatalytic nanofiber materials through various methodologies has drawn considerable attention. The electrospinning technique has been established as a prevalent method for fabricating nanofiber-structured materials, owing to its advantageous properties, including the ability for mass production and the assurance of high continuity.
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April 2025
Cellular and Molecular Research Center, Medical Basic Sciences Research Institute, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran.
Because acute kidney injuries (AKI) are one of the critical health problems worldwide, studies on the risk factors, mechanisms, and treatment strategies seem necessary. Glycerol (GLY), known to induce cell necrosis via myoglobin accumulation in renal tubules, is widely used as an AKI model. This study aimed to evaluate the protective effects of gallic acid (GA) against GLY-induced AKI.
View Article and Find Full Text PDFWater Res X
May 2025
School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, PR China.
Widespread polyethylene terephthalate microplastics (PET MPs) have played unintended role in nitrous oxide (NO) turnovers (i.e., production and consumption) at wastewater treatment plants (WWTPs).
View Article and Find Full Text PDFFront Pharmacol
January 2025
Department of Emergency Medicine, Qilu Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China.
Sustained production of reactive oxygen species (ROS) and an imbalance in the antioxidant system have been implicated in the development of cardiovascular diseases (CVD), especially when combined with diabetes, hypercholesterolemia, and other metabolic disorders. Among them, NADPH oxidases (NOX), including NOX1-5, are major sources of ROS that mediate redox signaling in both physiological and pathological processes, including fibrosis, hypertrophy, and remodeling. Recent studies have demonstrated that mitochondria produce more proteins and energy in response to adverse stress, corresponding with an increase in superoxide radical anions.
View Article and Find Full Text PDFFront Nutr
January 2025
College of Animal Science and Technology, Henan Agricultural University, Zhengzhou, China.
Improving mammary gland epithelial cells proliferation through nutrition is an important approach for enhancing sow milk production and piglet growth. An intermediate metabolite of valine, 3-hydroxyisobutyrate (3-HIB), regulates cellular lipid metabolism. In the present study, we investigated the effects of 3-HIB on porcine mammary gland epithelial cells proliferation and lipid metabolism.
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