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Ángel G. Polanco Rodríguez M. Inmaculada Riba López T. Ángel DelValls Casillas Patrizia Quattrocchi Fernando J. Álvarez Cervera Francisco J. Solorio Sánchez 《人类与生态风险评估》2015,21(7):1960-1979
In order to analyze risk perception related to the use and handling of organochlorine pesticides (OCP) in agricultural and livestock activities among Maya communities of Yucatan, Mexico, and to study their impact on public health and the environment, we conducted an analytical study applying 274 semi-structured interviews in 11 municipalities in the zone called “Ring of Cenotes.” The harmful effects of agrochemicals on water supplies, soils, air, and human health were considered, including the indoor use of pesticides to preserve harvest products. Recent studies showed high levels of OCP in groundwater. A generalized low risk perception related to human health and the environment due to pesticide use was found. Likewise, social parameters were analyzed, including the educational level, as well as risk factors related to groundwater karst vulnerability. Pesticides that have been banned by international conventions are still in use. The occurrence of some diseases such as cervical cancer, with a very high prevalence at the national level, and the practice of obtaining drinking water from polluted wells and sinkholes, may be associated with this low risk perception and with poor social conditions. Establishing programs on health education, agro-ecological production alternatives, and water chemical quality monitoring is recommended. 相似文献
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González-Fernández E de-los-Santos-Álvarez N Lobo-Castañón MJ Miranda-Ordieres AJ Tuñón-Blanco P 《Biosensors & bioelectronics》2011,26(5):2354-2360
An RNA aptamer is proposed as a recognition element for the detection of tobramycin in human serum. A displacement assay was developed using faradaic-electrochemical impedance spectroscopy (F-EIS) as a detection technique. Two modified aptamers, a partially (ATA) and a fully O-methylated aptamer (FATA) were evaluated and compared. The affinity constant, K(D), for both aptamers was estimated by F-EIS resulting virtually identical within the experimental error. The selectivity towards other aminoglycosides was also studied. The analytical characteristics were evaluated in aqueous solution using both aptamers and FATA was selected for human serum experiments. Using a 1:0.5 dilution of the serum, a linear range between 3 μM and 72.1 μM was obtained, which included the therapeutic range of the antibiotic. 相似文献
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Galofré JC Gómez-Sáez JM álvarez Escola C álvarez García E Anda Api?aniz E Calleja A Donnay S Lucas-Martin A Menéndez Torre E Navarro González E Pereg V Pérez Corral B Santamaría Sandi J Riesco Eizaguirre G Zafón Llopis C;Toma de posición del Grupo de Trabajo de Cáncer de Tiroides de la Sociedad Espa?ola de Endocrinología y Nutrición 《Endocrinología y nutrición》2011,58(8):381-386
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Alvarado-Esquivel C Urbina-Álvarez JD Estrada-Martínez S Torres-Castorena A Molotla-de-León G Liesenfeld O Dubey JP 《Parasitology international》2011,60(2):151-155
There are conflicting reports concerning the association of Toxoplasma gondii infection and schizophrenia in humans. Therefore, we determined such association in a Mexican population of Mestizo ethnicity. Through a case-control study design, 50 schizophrenic patients and 150 control subjects matched by gender, age, residence place, and ethnicity were examined with enzyme-linked immunoassays for the presence and levels of T. gondii IgG antibodies and for the presence of T. gondii IgM antibodies. Schizophrenic patients attended a public psychiatric hospital in Durango City, Mexico, and the control group consisted of individuals of the general population of the same city. Socio-demographic, clinical and behavioral characteristics from the study subjects were also obtained. Both the seroprevalence and the level of T.gondii IgG antibodies were higher in schizophrenic patients (10/50; 20%) than in control subjects (8/150; 5.3%) (OR=4.44; 95% CI: 1.49-13.37; P=0.003). The IgG T. gondii levels higher than 150 IU/ml were more frequently observed in patients than in controls (10% versus 2%, respectively; P=0.02). One (50%) of the two patients with recently diagnosed schizophrenia and none of the controls had T. gondii IgM antibodies (P=0.01). T. gondii seropositivity was significantly higher in patients with a history of cleaning cat excrement (P=0.005), and suffering from simple schizophrenia (ICD-10 classification: F20.6) (P=0.03) than patients without these characteristics. Toxoplasma seroprevalence was also significantly higher in patients with simple schizophrenia (F20.6) than in those with paranoid schizophrenia (F20.0) (P=0.02). This study provides elements to clarify the controversial information on the association of T. gondii infection and schizophrenia. 相似文献
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There is increasing evidence that several reversible oxidative post-translational modifications of protein cysteines participate in cell signalling. Specific proteomic techniques are required to identify these modifications and to study their regulation in different cell processes, that are collectively known as thiol redox proteomics. Recently, fluorescence derivatization methods have been developed that enable these post-translational modifications to be studied using proteomic workflows based on two-dimensional electrophoresis, which is a relatively accessible and affordable technique. As well as enabling a large number of samples to be processed, two-dimensional electrophoresis has the advantage that it does not rely on the intensive use of mass spectrometers. This methodology allows to "visualise" redox changes in a broad context and, although identification of the modified residues is not so straightforward, complementary derivatization can overcome this drawback. Here we review the different derivatization strategies that have been employed in these studies, comparing their advantages and potential limitations. We also review the applications and results obtained, with particular emphasis on those involving (patho)physiological stimuli, thereby showing the potential of these techniques to study the thiol redox proteome. 相似文献
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Avila-Ríos S García-Morales C Garrido-Rodríguez D Ormsby CE Hernández-Juan R Andrade-Villanueva J González-Hernández LA Torres-Escobar I Navarro-Álvarez S Reyes-Terán G;Mexican HIV Molecular Epidemiology Project Group 《PloS one》2011,6(11):e27812