70 research outputs found
Liquid Chromatography-Tandem Mass Spectrometry Analysis of Perfluorooctane Sulfonate and Perfluorooctanoic Acid in Fish Fillet Samples
Perfluorooctane sulfonate (PFOS) and perfluorooctanoic (PFOA) acid are persistent contaminants which can be found in environmental and biological samples. A new and fast analytical method is described here for the analysis of these compounds in the edible part of fish samples. The method uses a simple liquid extraction by sonication, followed by a direct determination using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The linearity of the instrumental response was good, with average regression coefficients of 0.9971 and 0.9979 for PFOS and PFOA, respectively, and the coefficients of variation (CV) of the method ranged from 8% to 20%. Limits of detection (LOD) were 0.04 ng/g for both the analytes and recoveries were 90% for PFOS and 76% for PFOA. The method was applied to samples of homogenized fillets of wild and farmed fish from the Mediterranean Sea. Most of the samples showed little or no contamination by perfluorooctane sulfonate and perfluorooctanoic acid, and the highest concentrations detected among the fish species analyzed were, respectively, 5.96 ng/g and 1.89 ng/g. The developed analytical methodology can be used as a tool to monitor and to assess human exposure to perfluorinated compounds through sea food consumption
Combination of antibodies directed against different ErbB3 surface epitopes prevents the establishment of resistance to BRAF/MEK inhibitors in melanoma
Patients with metastatic melanoma bearing V600 mutations in BRAF oncogene clinically benefit from the treatment with BRAF inhibitors alone or in combination with MEK inhibitors. However, a limitation to such treatment is the occurrence of resistance. Tackling the adaptive changes helping cells survive from drug treatment may offer new therapeutic opportunities. Very recently the ErbB3 receptor has been shown to act as a central node promoting survival of BRAF mutated melanoma. In this paper we first demonstrate that ErbB3/AKT hyperphosphorylation occurs in BRAF mutated melanoma cell lines following exposure to BRAF and/or MEK inhibitors. This strongly correlates with increased transcriptional activation of its ligand neuregulin. Anti-ErbB3 antibodies impair the establishment of de novo cell resistance to BRAF inhibition in vitro. In order to more potently ablate ErbB3 activity we used a combination of two anti-ErbB3 antibodies directed against distinct epitopes of its extracellular domain. These two antibodies in combo with BRAF/MEK inhibitors potently inhibit in vitro cell growth and tumor regrowth after drug withdrawal in an in vivo xenograft model. Importantly, residual tumor masses from mice treated by the antibodies and BRAF/ERK inhibitors combo are characterized almost exclusively by large necrotic areas with limited residual areas of tumor growth. Taken together, our findings support the concept that triple therapy directed against BRAF/MEK/ErbB3 may be able to provide durable control of BRAF mutated metastatic melanoma
Inhibition of Stearoyl-CoA desaturase 1 reverts BRAF and MEK inhibition-induced selection of cancer stem cells in BRAF-mutated melanoma
Combination therapy with BRAF and MEK inhibitors significantly improves survival in BRAF mutated melanoma patients but is unable to prevent disease recurrence due to the emergence of drug resistance. Cancer stem cells (CSCs) have been involved in these long-term treatment failures. We previously reported in lung cancer that CSCs maintenance is due to altered lipid metabolism and dependent upon Stearoyl-CoA-desaturase (SCD1)-mediated upregulation of YAP and TAZ. On this ground, we investigated the role of SCD1 in melanoma CSCs
Critical review of economic evaluation studies of interventions promoting low-fat diets
Various national and local policies encouraging healthy eating have recently been proposed. This study aims to summarize and critically assess economic evaluation studies of direct (e.g., diet counseling) and indirect (e.g., food labeling) interventions aimed at improving dietary habits.
We performed a systematic literature review by searching three databases (PubMed, Ovid Medline, Embase) using a combination of diet-related (fat, diet, intake, nutrition) and economics-related (cost-effectiveness, cost-benefit, cost-utility, health economics, economic evaluation) keywords.
Our search yielded 38 studies. The studies varied in target populations (e.g., healthy or unhealthy subjects), study designs (e.g., modeling, experiments), economic evaluation methods and health/economic outcomes. In general, all provide limited experimental evidence and adopt the framework of economic evaluations in healthcare. Certain important aspects are not well considered: (i) the non-health-related effects of nutrition interventions on well-being; (ii) the private nature of food expenditures ; (iii) the distributional effects on food expenditures across socio-economic groups; and (iv) the general economic implications (e.g., agro-foods, import/export) of such interventions. Overall, the methodology for the economic evaluation of nutrition interventions should be substantially improved
Critical review of economic evaluation studies of interventions promoting low-fat diets
Various national and local policies encouraging healthy eating have recently been proposed. This study aims to summarize and critically assess economic evaluation studies of direct (e.g., diet counseling) and indirect (e.g., food labeling) interventions aimed at improving dietary habits.
We performed a systematic literature review by searching three databases (PubMed, Ovid Medline, Embase) using a combination of diet-related (fat, diet, intake, nutrition) and economics-related (cost-effectiveness, cost-benefit, cost-utility, health economics, economic evaluation) keywords.
Our search yielded 38 studies. The studies varied in target populations (e.g., healthy or unhealthy subjects), study designs (e.g., modeling, experiments), economic evaluation methods and health/economic outcomes. In general, all provide limited experimental evidence and adopt the framework of economic evaluations in healthcare. Certain important aspects are not well considered: (i) the non-health-related effects of nutrition interventions on well-being; (ii) the private nature of food expenditures ; (iii) the distributional effects on food expenditures across socio-economic groups; and (iv) the general economic implications (e.g., agro-foods, import/export) of such interventions. Overall, the methodology for the economic evaluation of nutrition interventions should be substantially improved
Palm oil and blood lipid–related markers of cardiovascular disease: a systematic review and meta-analysis of dietary intervention trials
Background: Palm oil (PO) may be an unhealthy fat because of its high saturated fatty acid content.
Objective: The objective was to assess the effect of substituting PO for other primary dietary fats on blood lipid–related markers of coronary heart disease (CHD) and cardiovascular disease (CVD). Design: We performed a systematic review and meta-analysis of dietary intervention trials. Studies were eligible if they included original data comparing PO-rich diets with other fat-rich diets and analyzed at least one of the following CHD/CVD biomarkers: total cholesterol (TC), low-density lipoprotein (LDL) cholesterol, high- density lipoprotein (HDL) cholesterol, TC/HDL cholesterol, LDL cholesterol/HDL cholesterol, triacylglycerols, apolipoprotein A-I and B, very-low-density lipoprotein cholesterol, and lipoprotein(a). Results: Fifty-one studies were included. Intervention times ranged from 2 to 16 wk, and different fat substitutions ranged from 4% to 43%. Comparison of PO diets with diets rich in stearic acid, mono- unsaturated fatty acids (MUFAs), and polyunsaturated fatty acids (PUFAs) showed significantly higher TC, LDL cholesterol, apoli- poprotein B, HDL cholesterol, and apolipoprotein A-I, whereas most of the same biomarkers were significantly lower when com- pared with diets rich in myristic/lauric acid. Comparison of PO-rich diets with diets rich in trans fatty acids showed significantly higher concentrations of HDL cholesterol and apolipoprotein A-I and sig- nificantly lower apolipoprotein B, triacylglycerols, and TC/HDL cholesterol. Stratified and meta-regression analyses showed that the higher concentrations of TC and LDL cholesterol, when PO was substituted for MUFAs and PUFAs, were not significant in young people and in subjects with diets with a lower percentage of energy from fat.
Conclusions: Both favorable and unfavorable changes in CHD/ CVD risk markers occurred when PO was substituted for the pri- mary dietary fats, whereas only favorable changes occurred when PO was substituted for trans fatty acids. Additional studies are needed to provide guidance for policymaking
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