Araceli Amaya-Chávez

Oxidative stress induced on Cyprinus carpio by contaminants present in the water and sediment of Madin Reservoir.

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 Atizapán, 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.

Dificultades en la clasificación del síndrome metabólico. El ejemplo de los adolescentes en México

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

An integrated electrocoagulation-phytoremediation process for the treatment of mixed industrial wastewater.

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.

Prescripción de medicamentos en una clínica odontológica de una universidad mexicana

Resumen Objetivo Evaluar la prescripcion de medicamentos en una clinica odontologica de una universidad mexicana. Metodo Mediante un estudio observacional y descriptivo, se analizaron 698 prescripciones odontologicas en 14 servicios clinicos que conforman la clinica en estudio, enfocados a la conservacion y restauracion de la salud bucal en enero-junio 2005. Se registraron criterios como: medicamento prescrito, indicacion, dosis, intervalo de dosificacion, individualizacion de la terapia, duracion de tratamiento y presencia de interacciones farmacologicas potenciales. Para determinar la inadecuacion en los criterios de prescripcion se comparo la informacion obtenida en recetas y expedientes clinicos, con la de la literatura especializada. Resultados Los medicamentos mas prescritos fueron paracetamol, naproxeno, ampicilina y dicloxacilina en 43,26, 15,38, 7,45 y 7,02%. La indicacion, dosis e intervalo de dosificacion fueron los criterios con mayor inadecuacion en la prescripcion. Las principales interacciones potenciales fueron entre los antiinflamatorios no esteroideos con el captopril y la amoxicilina. Conclusiones Con lo anterior, se determino que el 37,25% de las prescripciones fueron inadecuadas. A traves de este estudio se establecieron estrategias que permitiran en un futuro tener una politica de uso racional de los medicamentos empleados.

Effects of a physical activity program on markers of endothelial dysfunction, oxidative stress, and metabolic status in adolescents with metabolic syndrome.

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.

Responses of three benthic organisms (Hyallela azteca, Limnodrillus hoffmeisteri and Stagnicola attenuata) to natural sediment spiked with zinc when exposed in single or multi-species test systems

In order to determine the influence of the presence of one or more species in a system on Zn toxic response, acute (LC50 at 72 h) and sublethal toxicity (Zn uptake kinetics, and quantification of total protein content and lipid peroxidation levels) were evaluated in three benthic organisms (Hyallela azteca, Limnodrillus hoffmeisteri and Stagnicola attenuata). They were exposed either singly or together (single or multi-species test systems) to Zn-spiked sediment from Ignacio Ramírez Reservoir. Both assays showed that Zn-spiked sediments from Ignacio Ramírez Reservoir were toxic to S. attenuata, L. hoffmeisteri and H. azteca, and that toxic response was modified according to the number of species in the system. These differences may be due to multiple factors: such as benthic bioturbation which modifies physical and chemical characteristics of sediments and affects the fate and partitioning of sediment-bond contaminants, such as spiked Zn or other pollutants in sediments from Ignacio Ramírez Reservoir. In addition, the presence of more than one species in the system may lead to microenvironmental changes (pH, temperature, and organic matter and metabolic waste content), which can also contribute to toxic response differences. Also, particular characteristics of each of the species involved in the study became evident. The snail and amphipod are facultative benthic organisms, while the worm is obligate. Such way of life differences may have modified the bioavailability of contaminants, determining their toxicity.

Removal of Pb, Cu, Cd, and Zn Present in Aqueous Solution Using Coupled Electrocoagulation-Phytoremediation Treatment

This study presents the results of a coupled electrocoagulation-phytoremediation treatment for the reduction of copper, cadmium, lead, and zinc, present in aqueous solution. The electrocoagulation was carried out in a batch reactor using aluminum electrodes in parallel arrangement; the optimal conditions were current density of 8 mA/cm2 and operating time of 180 minutes. For phytoremediation the macrophytes, Typha latifolia L., were used during seven days of treatment. The results indicated that the coupled treatment reduced metal concentrations by 99.2% Cu, 81.3% Cd, and 99.4% Pb, while Zn increased due to the natural concentrations of the plant used.

Tolerance and hyperaccumulation of a mixture heavy metals (Cu, Pb, Hg and Zn) by four aquatic macrophytes.

ABSTRACT In the present investigation, four macrophytes, namely Typha latifolia (L.), Lemna minor (L.), Eichhornia crassipes (Mart.) Solms-Laubach, and Myriophyllum aquaticum (Vell.) Verdc, were evaluated for their heavy metal (Cu, Pb, Hg, and Zn) hyperaccumulation potential under laboratory conditions. Tolerance analyses were performed for 7 days of exposure at five different treatments of the metals mixture (Cu+2, Hg+2, Pb+2, and Zn+2). The production of chlorophyll and carotenoids was determined at the end of each treatment. L. minor revealed to be sensitive, because it did not survive in all the tested concentrations after 72 hours of exposure. E. crassipes and M. aquaticum displayed the highest tolerance to the metals mixture. For the most tolerant species of aquatic macrophytes, The removal kinetics of E. crassipes and M. aquaticum was carried out, using the following mixture of metals: Cu (0.5 mg/L) and Hg, Pb, and Zn 0.25 mg/L. The obtained results revealed that E. crassipes can remove 99.80% of Cu, 97.88% of Pb, 99.53% of Hg, and 94.37% of Zn. M. aquaticum withdraws 95.2% of Cu, 94.28% of Pb, 99.19% of Hg, and 91.91% of Zn. The obtained results suggest that these two species of macrophytes could be used for the phytoremediation of this mixture of heavy metals from the polluted water bodies.