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Organochlorine pesticides (OCPs) can cause environmental damage and human health risks since they are lipophilic compounds with high resistance to degradation and long half-lives in humans. As most persistent OCPs have been banned years ago, it is expected to find these compounds at trace levels in environment. Therefore, increasingly sensitive and reliable analytical techniques are required to ensure effective monitoring of these compounds. The aim of this review is to discuss extraction and clean-up methods used to monitor OCP residues in milk, reported in the last 20 years. To carry out this review, an exhaustive bibliographic review was conducted. Despite the disadvantages of conventional extraction and clean-up methods, such as liquid-liquid, solid-phase or Soxhlet extractions, these procedures are still used due to their reliability. New extraction methods, like solid-phase microextraction, matrix solid-phase dispersion or QuEChERS, have not been thoroughly evaluated for OCP determination in milk. Almost all the methodologies analyzed in this review presented good performance characteristics according to the performance acceptability criteria set in SANCO's procedure. Comparison between limits of quantification (LOQ) and detection (LOD), for the reported methodologies, is not always possible due to the heterogeneity of the units. Thus, researchers should take into account an homogenization of LOD and LOQ units, according to the international regulations and MRLs established. Finally, more research is necessary to obtain the ideal methodology for OCPs determination in milk, which comprises the environmentally friendly characteristics of the new techniques and the reliability of the traditional methodologies.

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Cardiovascular disease is originated in the vascular endothelium, which controls the homeostasis and the filtration and diffusion of molecules from blood to the tissues. The classical cardiovascular risk factors (CRFs) act directly on the endothelium through an increase in the production of reactive oxygen species, promoting an endothelial activation mediated by the expression of adhesion and proinflammatory molecules, which lead to endothelial dysfunction, the progression of the atherosclerotic plaque, and the onset of cardiovascular disease. The objective of this study was to analyze the association of superoxide dismutase, catalase, gluthatione peroxidase, and lipoperoxidation with fibrinogen, interleukin (IL)-6, tumor necrosis factor-α, and vascular cell adhesion molecule (VCAM)-1 in subjects with cardiovascular risk (CVR) and CRF. This was a cross-sectional study of 114 individuals; oxidative stress (superoxide dismutase, catalase, gluthatione peroxidase, and lipoperoxidation) and inflammatory (fibrinogen, IL-6, tumor necrosis factor-α, and VCAM-1) biomarkers were measured; a CVR score (Framingham) and its CRF were taken into consideration to classify the participants. Twenty-nine subjects out of a total of 114 had high CVR. Smokers and subjects with diabetes (43 subjects) were excluded from the low CVR group. Significant decreases in lipoperoxidation, IL-6, and VCAM-1 and an increase in SOD were found in the high CVR group (P ≤ 0.05). Individual analysis of each CRF in the 114 subjects revealed a different pattern in the biomarkers' statistical differences. Concluding that the biomarkers show statistical differences in each CRF, especially IL-6, VCAM-1, and SOD; therefore, these are highly recommended to be used as biomarkers of the oxidative stress and inflammatory status in CVR.

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The metabolic syndrome (MetS) is a precursor of diabetes. Physical activity (PA) improves endothelial dysfunction and may benefit patients with MetS. Aims. To evaluate the effect of a physical activity (PA) program on markers of endothelial dysfunction and oxidative stress in adolescents with (MetS). Methods. We carried out a cohort study of 38 adolescents with and without MetS (18 females and 20 males). All participants completed a 3-month PA program. All variables of the MetS as well as markers of endothelial dysfunction and oxidative stress tests were evaluated. Results. Females with and without MetS showed significant differences for almost all components of the MetS, whereas males were significantly different in half of the components. After the PA program, components of the MetS were not different from baseline values except for HDL-C levels. Some baseline endothelial dysfunction markers were significantly different among adolescents with and without MetS; however, after the PA program, most of these markers significantly improved in subjects with and without MetS. Conclusion. PA improves the markers of endothelial dysfunction in adolescents with MetS although other changes in the components of the MetS were not observed. Perhaps the benefits of PA on all components of MetS would appear after a PA program with a longer duration.

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The elimination of organic contaminants in highly complex wastewater was tested using a combination of the techniques: electrocoagulation with aluminum electrodes and phytoremediation with Myriophyllum aquaticum. Under optimal operating conditions at a pH of 8 and a current density of 45.45 A m(-2), the electrochemical method produces partial elimination of contaminants, which was improved using phytoremediation as a polishing technique. The combined treatment reduced chemical oxygen demand (COD) by 91%, color by 97% and turbidity by 98%. Initial and final values of contaminants in wastewaters were monitored using UV-vis spectrometry and cyclic voltammetry. Finally, the morphology and the elemental composition of the biomass were characterized with using scanning electron microscopy (SEM) and energy dispersion spectroscopy (EDS). The presence of Al in the roots of plants in the system indicates that the aluminum present in the test solution could be absorbed.

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OBJETIVO. Determinar la diferencia entre las definiciones del National Cholesterol Education Program Adult Treatment Panel (ATPIII) y de la International Diabetes Federation (IDF) para síndrome metabólico (SM) en adolescentes mexicanos. MATERIAL Y MÉTODOS. Estudio transversal en 575 adolescentes de 14 a 16 años. Se utilizaron pruebas t de Student, ji cuadrada y correlación de Spearman. RESULTADOS. La prevalencia de SM fue mayor por ATPIII (18.6 por ciento) versus IDF (8.2 por ciento) (p<0.001), con 41.1 por ciento de concordancia. CONCLUSIONES. Existe una diferencia estadística de la prevalencia del SM en adolescentes mexicanos entre las dos definiciones.

OBJECTIVE. Determine the difference between the National Cholesterol Education Program Adult Treatment Panel (ATPIII) definition of the diagnosis of metabolic syndrome (MS) in Mexican adolescents and that by the International Diabetes Federation (IDF). MATERIAL AND METHODS. We conducted a cross-sectional study of 575 adolescents aged 14 to 16 years using the student's t test, chi square and Spearman correlation. RESULTS. The prevalence of MS was higher by ATPIII (18.6 percent) than by IDF (8.2 percent) (p <0.001) and there was a concordance of 41.1 percent. CONCLUSIONS. There is a statistical difference in the prevalence of MS depending on the definition.

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Madin Reservoir (MR), located in the State of Mexico, is fed mainly by the Rio Tlalnepantla. MR supplies potable water to the municipalities of Naucalpan and Atizapan, and various recreational activities take place in its vicinity, such as sailing and the fishing of diverse species including the common carp Cyprinus carpio. The purpose of this study was to determine the toxic effects of contaminants present in MR water and sediment on C. carpio. Five sampling stations were selected (those considered to have the most problems due to discharges). Water and sediment samples were taken and toxicity studies were performed, including acute toxicity (lethality) and subacute toxicity assays. The biomarkers used in the subacute assays were lipid peroxidation (LPX) and activity of the antioxidant enzymes superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX) in the liver and brain of test organisms. These biomarkers were also evaluated in local carp, i.e. carp with chronic exposure in situ to reservoir contaminants. Results show that contaminants in the water and sediment of the different sampling stations induce oxidative stress, this toxicity being more evident in samples from stations near the entry point of the Rio Tlalnepantla tributary and in local carp. This may be due to high contaminant levels as well as the fact that the physicochemical characteristics of the matrices might favor their bioavailability. Thus, both the water and sediment of this reservoir are contaminated with xenobiotics hazardous to C. carpio, a species consumed by the local human population.

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Several studies of fish have shown that aluminum may induce hypoxia, hypercapnia, metabolic acidosis, and respiratory failure. In lymphocytes, morphologic abnormalities and reduced immune activity have been observed. Nevertheless, there is little data on oxidative stress and such data are essential in order to identify its mechanism of action. The common carp Cyprinus carpio, an omnivorous fish commonly used in commercial aquaculture, has been proposed as a test organism in toxicologic assays due to its economic importance and wide geographic distribution. The aim of this work was to evaluate Al-induced oxidative stress in lymphocytes of the common carp C. carpio. Specimens were exposed to three different concentrations of Al (0.05, 120, and 239 mg/l) in a static exposure system for 96 h. At the end of the exposure period, blood was collected and lymphocytes were separated. Lipid peroxidation, oxidized protein content and the activity of superoxide dismutase, catalase, and glutathione peroxidase were measured. Results show that the tested Al concentrations modified the activity of antioxidant enzymes and elicited higher levels of lipid peroxidation and oxidized proteins. The degree of damage induced was concentration and tissue dependent.

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OBJECTIVE: Determine the difference between the National Cholesterol Education Program Adult Treatment Panel (ATPIII) definition of the diagnosis of metabolic syndrome (MS) in Mexican adolescents and that by the International Diabetes Federation (IDF). MATERIAL AND METHODS: We conducted a cross-sectional study of 575 adolescents aged 14 to 16 years using the student's t test, chi square and Spearman correlation. RESULTS: The prevalence of MS was higher by ATPIII (18.6%) than by IDF (8.2%) (p <0.001) and there was a concordance of 41.1%. CONCLUSIONS: There is a statistical difference in the prevalence of MS depending on the definition.

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