RESUMEN
The physiological system of molluscs, particularly pro-oxidant and antioxidant mechanisms, could be altered by pollutants and induce disturbance on health status and productive parameters of aquatic organisms, such as oyster. Therefore, the aim of this study was to evaluate the chemical contamination in water (total metals and polycyclic aromatic hydrocarbons) and oxidative stress parameters in oysters (Crassostrea corteziensis) in Camichin estuary, located in Mexican Tropical Pacific. The results obtained showed the presence of arsenic, lead and zinc, as well as naphthalene, pyrene and benzo[a]pyrene in concentrations relatively higher than criteria established by local and international guidelines. Regarding the biomarkers of oxidative stress response (H2O2 and O2 concentration, catalase activity, lipid peroxidation, and hydroperoxide concentration), differences between oyster from estuary and control group were significant. These results indicate that these pollutants could be related with oxidative stress detected in oyster.
Asunto(s)
Antioxidantes/metabolismo , Estrés Oxidativo , Especies Reactivas de Oxígeno/metabolismo , Contaminantes Químicos del Agua , Animales , Monitoreo del Ambiente , Estuarios , Peróxido de Hidrógeno/metabolismo , Peroxidación de Lípido , México , Ostreidae/efectos de los fármacos , Ostreidae/metabolismoRESUMEN
Chlorpyrifos and methyl parathion are among the most widely used insecticides in the world. Human populations are constantly exposed to low doses of both due to their extensive use and presence in food and drinking water. Glutathione S-transferase (GST) catalyzes the conjugation of glutathione on electrophilic substrates and is an important line of defense in the protection of cellular components from reactive species. GST alpha1 (GSTA1) is the predominant isoform of GST expressed in the human liver; thus, determining the effect of insecticides on GSTA1 transcription is very important. In the present study, we analyzed the effects of methyl parathion and chlorpyrifos on GSTA1 gene expression in HepG2 cells using real time PCR, and activity and immunoreactive protein assays. The results demonstrated that exposure to methyl parathion and chlorpyrifos increased the level of GSTA1 mRNA, GSTA1 immunoreactive protein and GST activity relative to a control. These results demonstrated that these insecticides can increase the expression of GSTA1. In conclusion, HepG2 cell cultures treated with methyl parathion and chlorpyrifos could be a useful model for studying the function of GSTA1 and its role in the metabolism of xenobiotics in the liver.
Asunto(s)
Cloropirifos/toxicidad , Glutatión Transferasa/genética , Células Hep G2/efectos de los fármacos , Metil Paratión/toxicidad , Plaguicidas/toxicidad , Supervivencia Celular/efectos de los fármacos , Expresión Génica/efectos de los fármacos , Glutatión/genética , Glutatión/metabolismo , Glutatión Transferasa/metabolismo , Células Hep G2/enzimología , Humanos , Hígado/efectos de los fármacos , Hígado/metabolismo , ARN Mensajero/metabolismo , Reacción en Cadena en Tiempo Real de la PolimerasaRESUMEN
Endosulfan is a hazardous organochlorine pesticide banned or restricted in several countries. However, it has been found in the environment and in animal samples. To study a potential way to bioremediate soils contaminated with this pesticide, two plant species of the genus Ocimum were studied: Ocimum basilicum L. and Ocimum minimum L., since they are economically feasible and well adapted to the climatic conditions of the Nayarit zone (Mexican pacific coast). Young plants were transplanted into soil experimentally polluted with endosulfan. Growth of both species was not affected by endosulfan, the plants grew, flourished, and produced seeds; 30 days later, endosulfan concentration was lower in the soil with O. basilicum than in the soil without plants. On day 90, no differences in endosulfan concentrations were found between soil with or without O. minimum. At day 1, plants in the polluted soil showed lipoperoxidation, as measured by thiobarbituric acid-reactive species (TBARS). Interestingly, a higher TBARS value was observed at day 3 in transplanted plants as compared to non-transplanted plants. In conclusion, both species can endure endosulfan pollution (as high as 1 g kg(-1)) in soils. O. basilicum seems to be an adequate candidate for bioremediation of soils polluted with endosulfan.
Asunto(s)
Endosulfano/toxicidad , Restauración y Remediación Ambiental/métodos , Ocimum/fisiología , Contaminantes del Suelo/toxicidad , Endosulfano/metabolismo , Peroxidación de Lípido , Ocimum/crecimiento & desarrollo , Contaminantes del Suelo/metabolismoRESUMEN
Substantial efforts have been devoted to developing and applying biomarkers for ecological risk assessment. Bivalve mollusks, such as mussels and oysters, are commonly used in environmental monitoring programs because of their wide geographical distribution, great sensitivity to environmental pollutants, and ability to accumulate anthropogenically derived chemicals at a high rate. Acetylcholinesterase (AChE) activity and metallothionein (MT's) content are representative specific biomarkers that indicate the presence of anticholinesterasic compounds (like organophosphorus and carbamate pesticides) and metals, respectively. The aim of this study was to evaluate AChE activity and MT's content in Crassostrea corteziensis from Boca de Camichín estuary. The results obtained here showed that AChE activity was 65% lower in oysters from Boca de Camichín than in control organisms. In contrast, MT's content in collected organisms was not statistically different from that in control organisms. AChE activity and MT's content in oysters could be used as early biomarkers of effects and exposure to pesticides and heavy metals, respectively, in aquatic environments.
Asunto(s)
Acetilcolinesterasa/metabolismo , Crassostrea/efectos de los fármacos , Monitoreo del Ambiente/métodos , Branquias/efectos de los fármacos , Metalotioneína/metabolismo , Contaminantes Químicos del Agua/toxicidad , Animales , Biomarcadores/metabolismo , Crassostrea/enzimología , Branquias/enzimología , México , Océano Pacífico , Medición de Riesgo , Agua de Mar/química , Contaminantes Químicos del Agua/análisisRESUMEN
The effect of endosulfan (6,7,8,9,10,10-hexachloro-1,5,5a,6,9,9a-hexahydro-6,9-methano-2,4,3-benzodioxathiepin-3-oxide), an organochlorine pesticide, was evaluated on phagocytic (phagocytic index and percentage of active cells) and hematological parameters in Nile tilapia. Experimental data showed that an acute exposure to endosulfan (4.0 and 7.0 microg/L) induces a significant decrease in the phagocytic index and the percentage of active cells in peripherical blood of Nile tilapia. However, hemoglobin concentration (Hb), hematocrit (Hto), red blood cell count (RBC), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), and mean corpuscular hemoglobin concentration (MCHC) were not significantly altered in fish exposed to endosulfan compared with control group.
Asunto(s)
Células Sanguíneas/efectos de los fármacos , Endosulfano/toxicidad , Insecticidas/toxicidad , Fagocitosis/efectos de los fármacos , Animales , CíclidosRESUMEN
OBJECTIVES: To assess the frequency of carotid atherosclerosis and its relation to cardiovascular risk factors in a general elderly population of Mexico City. MATERIAL AND METHODS: B-mode ultrasonography was performed to investigate carotid atherosclerosis in 145 CUPA (a research project) participants, between July 1993 and January 1996. The outcome was then related to cardiovascular risk factors. RESULTS: Prevalence of ultrasound-detected carotid atherosclerosis was 64.8%. Intimal-medial thickening was detected in 64 subjects (44.1%) and carotid plaques in 82 (56.5%); Fifty-two subjects had both intimal-medial thickening and plaques. However, only 8 subjects had carotid plaques with severe stenosis (5.5%). There were no significant differences in the prevalence of atherosclerotic lesions (male 61.9%, female 66.0%). Carotid atherosclerosis was significantly associated with age (p < 0.0001), high blood pressure (p < 0.001), isolated systolic hypertension (p = 0.01), hypercholesterolemia (p = 0.04), and diabetes mellitus (p = 0.06). Prevalence of carotid atherosclerosis increased progressively with the number of vascular risk factors. CONCLUSIONS: There was a high prevalence of carotid atherosclerosis in this general elderly population of Mexico City, and was almost equal to that reported in developed western countries. Age, hypertension, hypercholesterolemia, and diabetes were the strongest predictors of atherosclerosis.
Asunto(s)
Enfermedades Cardiovasculares/diagnóstico por imagen , Enfermedades de las Arterias Carótidas/diagnóstico por imagen , Distribución por Edad , Anciano , Anciano de 80 o más Años , Enfermedades Cardiovasculares/epidemiología , Enfermedades de las Arterias Carótidas/epidemiología , Femenino , Humanos , Masculino , México/epidemiología , Persona de Mediana Edad , Prevalencia , Factores de Riesgo , Sensibilidad y Especificidad , Ultrasonografía Doppler de Pulso/métodos , Ultrasonografía Doppler de Pulso/estadística & datos numéricos , Población Urbana/estadística & datos numéricosRESUMEN
To evaluate the information about prevalence of hypertension at a national level, several articles published either within or outside Mexico from 1933 to 1995 were reviewed. Variables about criteria and methodology were considered: the BP readings, method used, cutting points to define hypertension, year for screen. There were 30 papers out of 7 states, 16 reporting the Federal District of Mexico, 3 from Jalisco, 3 from Yucatán and 2 from Tamaulipas, there was only one referring to the State of Mexico, one to Veracruz, one to Michoacán and another referring to Mexicans in USA; as whole population there were two, one by the Instituto Mexicano del Seguro Social and another by Secretaría de Salud. A wide variation in prevalence was found (0.47 to 30.9%) mainly attributed to different sampling, measurements and reporting methodology. Few information was disclosed regarding female and elderly populations. The trend is slightly increasing, as expected accordingly to other information sources, but the problem might actually be masked by bias interference. Most of the studies performed have contributed so far to explore the gross prevalence, but may not reach scientific evidence to base evaluations of preventive interventions. The problem may not just be happening in this country. Variability may be partially controlled following the international recommendations to record arterial blood pressure, but still, there is a lack of recommendations to uniform epidemiological reports. Otherwise the values of hypertension prevalence may not be useful for hypertension surveillance.
Asunto(s)
Hipertensión/epidemiología , Adolescente , Adulto , Distribución por Edad , Anciano , Niño , Femenino , Humanos , Masculino , México/epidemiología , Persona de Mediana Edad , Morbilidad/tendencias , PrevalenciaRESUMEN
In order to investigate the prevalence of atherosclerosis in Mexico, high resolution ultrasound and color Doppler flow imaging of carotid arteries were carried out in a group of participants in CUPA project, a cohort study started in 1989 among persons 60 years and older living permanently in a high rise in México City. Imaging studies included identification of 4 atherosclerosis related abnormalities: 1) intima media thickness; 2) kinkings and tortuousness; 3) non-stenosing plaques; and 4) significant carotid stenosis (> 50%). Analysis of 198 Doppler ultrasonographic studies in 56 males and 142 females showed an overall prevalence of atherosclerosis related lesions of 65.6%, with increasing frequency by age groups: 33% in younger than 65 year-old, 71% in 65-74 years, and up to 88% in the 75 years and older group. The prevalence of high grade stenosis was low (6%) whereas the overall frequency of non-stenosing plaques and intima-media thickness was higher than 60%. Intima-media thickness was more common in males while non-stenosing plaques and high grade stenosis were more frequent in females. However, there were not significant differences among women and men when atherosclerotic lesions were analyzed by age groups. This is the first report on the prevalence of atherosclerosis in a Mexican population using ultrasonography. Findings of the investigation document the high prevalence of atherosclerosis among elderly resident in Mexico City.