Search results for "OCR"
showing 10 items of 13223 documents
Circadian Rhythm and Concentration of Melatonin in Breast Cancer Patients
2020
Background: Melatonin is a biomarker of the central circadian clock and its chronobiotic actions entraining circadian rhythms to the light-dark cycle are well known. Reduction in melatonin levels and altered circadian rhythms have been associated with a high risk of breast cancer. Melatonin has also shown to display anti-proliferative effects on breast cancer growth and proliferation. Evaluation of melatonin circadian rhythm alterations in patients bearing breast cancer may have interesting prognostic and therapeutic applications. Objective: To review studies evaluating the circadian rhythm of melatonin in breast cancer patients. The effects of surgery and chemotherapy on melatonin secreti…
First international descriptive and interventional survey for cholesterol and non-cholesterol sterol determination by gas- and liquid-chromatography–…
2019
International audience; Serum concentrations of lathosterol, the plant sterols campesterol and sitosterol and the cholesterol metabolite 5alpha-cholestanol are widely used as surrogate markers of cholesterol synthesis and absorption, respectively. Increasing numbers of laboratories utilize a broad spectrum of well-established and recently developed methods for the determination of cholesterol and non-cholesterol sterols (NCS). In order to evaluate the quality of these measurements and to identify possible sources of analytical errors our group initiated the first international survey for cholesterol and NCS. The cholesterol and NCS survey was structured as a two-part survey which took place…
Metabolic classification and intervention opportunities for tumor energy dysfunction
2021
A comprehensive view of cell metabolism provides a new vision of cancer, conceptualized as tissue with cellular-altered metabolism and energetic dysfunction, which can shed light on pathophysiological mechanisms. Cancer is now considered a heterogeneous ecosystem, formed by tumor cells and the microenvironment, which is molecularly, phenotypically, and metabolically reprogrammable. A wealth of evidence confirms metabolic reprogramming activity as the minimum common denominator of cancer, grouping together a wide variety of aberrations that can affect any of the different metabolic pathways involved in cell physiology. This forms the basis for a new proposed classification of cancer accordin…
Mitochondrion at the Crossroad Between Nutrients and Epigenome.
2019
Epigenetic profile is the link between the regulation of nuclear gene expression and the environment. The most important factors capable of significantly affecting the cellular environment are the amount and quality of nutrients available. Mitochondria are both involved in the production of some of the molecules capable of directly affecting the epigenome and have a critical role in the conversion of nutrients into usable energy. Carbohydrate and fats are converted into ATP, acetyl-CoA, SAM, and NADH. These high-energy substrates are, in turn, capable of driving the epigenetic profile. We describe substances capable of affecting this mechanism. On the other hand, nutritional interventions c…
Rapid degradation of ABCA1 protein following cAMP withdrawal and treatment with PKA inhibitor suggests ABCA1 is a short-lived protein primarily regul…
2020
Objectives: ATP-binding cassette transporter A1 (ABCA1) is a key player in the reverse cholesterol transport (RCT) and HDL biogenesis. Since RCT is compromised as a result of ABCA1 dysfunction in diabetic state, the objective of this study was to investigate the regulation of ABCA1 in a stably transfected 293 cells expressing ABCA1 under the control of cAMP response element. Methods: To delineate transcriptional and posttranscriptional regulation of ABCA1, 293 cells were stably transfected with the full length ABCA1 cDNA under the control of CMV promoter harboring cAMP response element. cAMP-mediated regulation of ABCA1 and cholesterol efflux were studied in the presence of 8-Br-cAMP and af…
Hyperalphalipoproteinemia and Beyond: The Role of HDL in Cardiovascular Diseases
2021
Hyperalphalipoproteinemia (HALP) is a lipid disorder characterized by elevated plasma high-density lipoprotein cholesterol (HDL-C) levels above the 90th percentile of the distribution of HDL-C values in the general population. Secondary non-genetic factors such as drugs, pregnancy, alcohol intake, and liver diseases might induce HDL increases. Primary forms of HALP are caused by mutations in the genes coding for cholesteryl ester transfer protein (CETP), hepatic lipase (HL), apolipoprotein C-III (apo C-III), scavenger receptor class B type I (SR-BI) and endothelial lipase (EL). However, in the last decades, genome-wide association studies (GWAS) have also suggested a polygenic inheritance o…
Effects of Nandrolone Stimulation on Testosterone Biosynthesis in Leydig Cells
2016
Anabolic androgenic steroids (AAS) are among the drugs most used by athletes for improving physical performance, as well as for aesthetic purposes. A number of papers have showed the side effects of AAS in different organs and tissues. For example, AAS are known to suppress gonadotropin‐releasing hormone, luteinizing hormone, and follicle‐stimulating hormone. This study investigates the effects of nandrolone on testosterone biosynthesis in Leydig cells using various methods, including mass spectrometry, western blotting, confocal microscopy and quantitative real‐time PCR. The results obtained show that testosterone levels increase at a 3.9 μM concentration of nandrolone and return to the ba…
Genome-Wide Association Study for Serum Omega-3 and Omega-6 Polyunsaturated Fatty Acids: Exploratory Analysis of the Sex-Specific Effects and Dietary…
2020
Many early studies presented beneficial effects of polyunsaturated fatty acids (PUFA) on cardiovascular risk factors and disease. However, results from recent meta-analyses indicate that this effect would be very low or nil. One of the factors that may contribute to the inconsistency of the results is that, in most studies, genetic factors have not been taken into consideration. It is known that fatty acid desaturase (FADS) gene cluster in chromosome 11 is a very important determinant of plasma PUFA, and that the prevalence of the single nucleotide polymorphisms (SNPs) varies greatly between populations and may constitute a bias in meta-analyses. Previous genome-wide association studies (GW…
Protecting group-free radical decarboxylation of bile acids: Synthesis of novel steroidal substituted maleic anhydrides and maleimides and evaluation…
2017
Abstract We report the first Barton radical decarboxylation of unprotected bile acids via in situ irradiation of their thiohydroxamic esters in the presence of citraconic anhydride and citracoimide, leading to the synthesis a series of steroidal maleic anhydrides and maleimides as novel hybrid bile acids. The cytotoxic activities were evaluated on C6 rat glioma cells.
Cytotoxic effects induced by patulin, sterigmatocystin and beauvericin on CHO-K1 cells.
2015
Mycotoxins are produced by different genera of fungi; mainly Aspergillus, Penicillium and Fusarium. The natural co-occurrence of beauvericin (BEA), patulin (PAT) and sterigmatocystin (STE) has been proved in feed and food commodities. This study investigates the cytotoxicity of individual and combined mycotoxins BEA, PAT and STE. The cytotoxicity on immortalized ovarian cells (CHO-K1) was evaluated using the MTT assay. After 24, 48 and 72 h, the IC50 values were 2.9 μM for PAT and ranged from 10.7 to 2.2 μM and from 25.0 to 12.5 μM for BEA and STE, respectively. Cytotoxic interactions were assayed by the isobologram method, which provides a combination index (CI) value as a quantitative mea…