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Magnetically dependent photovoltages in permalloy films and gratings
Development and validation of a nomogram to predict the probability of death after surgical evacuation for traumatic intracranial hemorrhage
Digitized thermo-responsive shape memory matrix band for tooth restorations
Intratumoral microbiota, fatty acid metabolism, and tumor microenvironment constitute an unresolved trinity in colon adenocarcinoma
Association of composite dietary antioxidant index with mortality risk among adults with chronic kidney disease in NHANES
Tolterodine is a novel candidate for assessing CYP3A4 activity through metabolic volatiles to predict drug responses
Abstract Cytochrome P450 (CYP) 3A4 plays a major role in drug metabolism. Its activity could be determined by non-invasive and cost-effective assays, such as breath analysis, for the personalised monitoring of drug response. For the first time, we identify an isotopically unlabelled CYP3A4 substrate, tolterodine that leads to the formation of a non-toxic volatile metabolite, acetone, which could potentially be applied to monitor CYP3A4 activity in humans. In vitro biotransformation of tolterodine by HepG2 cells overexpressing CYP3A4, CYP2D6 or CYP2C9 was investigated by LC-MS analysis of cell culture supernatant for the non-volatile metabolite, N-dealkylated tolterodine, and PTR-ToF-MS analysis of the headspace for acetone. The highest level of the N-dealkylated metabolite was produced by HepG2-CYP3A4. Concentration dependent effects of tolterodine were analysed, resulting in TC50 values of 414 µM and 375 µM for HepG2-CYP3A4 and reference cells, respectively. Acetone and N-dealkylated tolterodine levels increased continuously over 24 h in HepG2-CYP3A4. Treatment with either a pan-CYP inhibitor, 1-aminobenzotriazole, or a CYP3A4 inhibitor, ketoconazole, considerably reduced the production of both metabolites in HepG2-CYP3A4 cells. These findings pave the way for the further development of non-invasive breath tests using unlabelled precursors to determine CYP enzyme activity in individuals.
Study on the performance and mechanism of graphene oxide / polyurethane composite modified asphalt
Diagnostic accuracy of human papillomavirus testing on self-collected samples among women referred for colposcopy
An investigation into cleaning quality of suction-type metal lumen instruments: a cross-sectional study
Invariance of the speckle pattern of the transmitted wave in periodic waveguides
Anti-angiogenic effects of cationic zinc (II) phthalocyanine derivatives through photodynamic therapy
Effect of sulfinate salt on bonding and polymerization of adhesive to intracoronally bleached dentin
Prevalence and predictors of infected diabetic foot ulcers (DFU) and DFU-related osteomyelitis amongst industrial workers wearing occupational safety footwear
Long-term tracking of neural and oligodendroglial development in large-scale human cerebral organoids by noninvasive volumetric imaging
A long-term analysis of oxidant (OX = O3 + NO2) and its local and regional levels in Tehran, Iran, a high NOx-saturated condition
Effectiveness of non-pharmacological intervention protocol for prevention of postoperative delirium in the surgical intensive care unit
Efficient recognition of Parkinson’s disease mice on stepping characters with CNN
Climate change adaptation strategies adopted by pastoralists in rangelands in Golestan province, Iran
Author Correction: Engineering amphiphilic alkenyl lipids for self-assembly in functional hybrid nanostructures
Long term study on blood glucose levels in wintering great tits Parus major in sites differing in artificial food availability
Abstract Blood glucose concentration is one of the fundamental biochemical indices in the physiology of birds and other vertebrates. Since glucose serves as the main fuel for metabolic energy, its proper level in the blood serum is crucial to the individual in terms of physiological health, which leads to applying it as an ecophysiological indicator. Such an indicator may be especially useful during energetically demanding periods, such as winter at northern latitudes. Therefore, the main objective of this paper was to examine the variation in blood glucose in wintering the great tits (Parus major) in nine consecutive winters at two sites that differed with respect to the amount of human-provided food. We assumed that trophic conditions resulting from the use of artificial feeders that vary between sites across the years would affect the metabolic performance of birds and their physiological condition, which should be reflected in the blood glucose levels of wintering individuals. We showed that both females and males were characterised by significantly higher glucose levels at the study site, which was characterised by the high accessibility to human-provided food sources (forest clearing) than at the site with low and irregular artificial feeding. The difference remained distinct throughout most of the winter seasons of the study. We also revealed a substantial variation between seasons in blood glucose concentration in the case of male great tits. In general, we show that avian blood glucose can be used as an ecophysiological indicator of the trophic conditions of the environment in which individuals from small passerine species winter.