Antioxidantes naturales y su efecto contra el estrés oxidante provocado por la contaminación por material particulado / Natural Antioxidants and their Effect Against Oxidative Stress Caused by Particulate Matter Pollution

Resumen La contaminación ambiental es uno de los factores que favorece el estrés oxidante, ya que expone al organismo a materiales diversos que generan radicales libres y afectan al sistema respiratorio, cardiovascular, inmunológico y nervioso de las personas más vulnerables como los niños, adultos mayores y personas con enfermedades crónicas. Para prevenir o reducir el estrés oxidante, el cual es un desequilibrio entre la producción de radicales libres y la capacidad del organismo de neutralizarlo, se recomienda consumir una dieta equilibrada y rica en antioxidantes naturales los cuales se encuentran diversos alimentos, especialmente en frutas y verduras con colores intensos, en las semillas y las especias. En las últimas décadas se ha demostrado la eficacia del consumo de antioxidantes naturales como: el resveratrol vino, el café, la curcumina, el ajo, la vitamina C, la vitamina E y el té verde que presentan efectos benéficos como: proteger membranas celulares, regular la expresión de genes relacionados con la inflamación, prevenir o reducir el daño endotelial, disminuir la frecuencia o severidad de enfermedades neurodegenerativas, hepáticas y pulmonares, así como estimular al sistema inmunológico.

Abstract Environmental pollution can promote oxidative stress by exposing the body to various elements and substances that generate free radicals, such as lead and vanadium. These free radicals can negatively impact the respiratory, cardiovascular, immune, and neurological systems of vulnerable populations, including children, the elderly, and those with chronic diseases. To prevent or reduce oxidative stress, it is recommended to consume a balanced diet rich in natural antioxidants. These antioxidants can be found in various foods, especially in fruits and vegetables with intense colors, seeds, and spices. In recent decades, the effectiveness of consuming natural antioxidants such as resveratrol found in wine, coffee, curcumin, garlic, vitamin C, vitamin E, and green tea has been demonstrated. These antioxidants have beneficial effects on the body, including the protection of cell membranes, regulation of gene expression associated with inflammation, prevention or reduction of endothelial damage, and the decrease or diminished severity of neurodegeneration, liver, and pulmonary disorders. Additionally, they stimulate the immune response.

EEG Dynamics of Error Processing and Associated Behavioral Adjustments in Preschool Children.

Preschool children show neural responses and make behavioral adjustments immediately following an error. However, there is a lack of evidence regarding how neural responses to error predict subsequent behavioral adjustments during childhood. The aim of our study was to explore the neural dynamics of error processing and associated behavioral adjustments in preschool children from unsatisfied basic needs (UBN) homes. Using EEG recordings during a go/no-go task, we examined within-subject associations between the error-related negativity (ERN), frontal theta power, post-error slowing, and post-error accuracy. Post-error accuracy increased linearly with post-error slowing, and there was no association between the neural activity of error processing and post-error accuracy. However, during successful error recovery, the frontal theta power, but not the ERN amplitude, was associated positively with post-error slowing. These findings indicated that preschool children from UBN homes adjusted their behavior following an error in an adaptive form and that the error-related theta activity may be associated with the adaptive forms of post-error behavior. Furthermore, our data support the adaptive theory of post-error slowing and point to some degree of separation between the neural mechanisms represented by the ERN and theta.

Seroepidemiología del paludismo en un grupo de migrantes en tránsito (Chiapas, 2008)

OBJETIVO: Conocer la prevalencia del paludismo y los factores asociados con la infección de migrantes en la frontera sur de México, durante 2008. MATERIAL Y MÉTODOS: En 706 migrantes, se investigó la infección activa mediante prueba rápida y PCR o pasada, mediante serología y se aplicó un cuestionario para investigar las condiciones asociadas con la infección. RESULTADOS: 85.6% provenía de Centroamérica. Ninguno presentó infección activa; 4.2% fue seropositivo y la mayoría provenía de los países con mayor incidencia de paludismo en la región. La seropositividad se asoció con el número de episodios previos de paludismo (RM=1.44; IC95% 1.04-2.00), años de permanencia en su comunidad de origen (RM=1.03; IC95% 1.00 -1.07) y conocimiento y automedicación con antipalúdicos (RM=3.38; IC95% 1.48-7.67). CONCLUSIONES: La exposición previa de migrantes al paludismo y las dificultades para su detección indican la necesidad de nuevas estrategias para la vigilancia epidemiológica para estas poblaciones.

OBJECTIVE: To know the prevalence of malaria and the factors associated with the infection in migrants in the southern border of Mexico, during 2008. MATERIALS AND METHODS: In 706 migrants, active malaria infection was investigated using a rapid diagnostic test and PCR and past infection using serology. A questionnaire was applied to investigate the conditions associated to infection. RESULTS: 85.6% originated from Central America, none presented an active infection, although 4.2% were seropositive, most of these came from the countries with the highest malaria incidence in the region. Seropositivity was associated with the number of previous malaria episodes (OR=1.44; IC95% 1.04-2.00), years living in their community of origin (OR=1.03; IC95% 1.00-1.07), and knowledge and self-medication with anti-malaria drugs (OR=3.38; IC95% 1.48-7.67). CONCLUSIONS:. The previous exposure of migrants and the difficulties for their detection indicate the need of new strategies for the epidemiological surveillance for these populations.

The extended fronto-striatal model of obsessive compulsive disorder: convergence from event-related potentials, neuropsychology and neuroimaging.

In this work, we explored convergent evidence supporting the fronto-striatal model of obsessive-compulsive disorder (FSMOCD) and the contribution of event-related potential (ERP) studies to this model. First, we considered minor modifications to the FSMOCD model based on neuroimaging and neuropsychological data. We noted the brain areas most affected in this disorder -anterior cingulate cortex (ACC), basal ganglia (BG), and orbito-frontal cortex (OFC) and their related cognitive functions, such as monitoring and inhibition. Then, we assessed the ERPs that are directly related to the FSMOCD, including the error-related negativity (ERN), N200, and P600. Several OCD studies present enhanced ERN and N2 responses during conflict tasks as well as an enhanced P600 during working memory (WM) tasks. Evidence from ERP studies (especially regarding ERN and N200 amplitude enhancement), neuroimaging and neuropsychological findings suggests abnormal activity in the OFC, ACC, and BG in OCD patients. Moreover, additional findings from these analyses suggest dorsolateral prefrontal and parietal cortex involvement, which might be related to executive function (EF) deficits. Thus, these convergent results suggest the existence of a self-monitoring imbalance involving inhibitory deficits and executive dysfunctions. OCD patients present an impaired ability to monitor, control, and inhibit intrusive thoughts, urges, feelings, and behaviors. In the current model, this imbalance is triggered by an excitatory role of the BG (associated with cognitive or motor actions without volitional control) and inhibitory activity of the OFC as well as excessive monitoring of the ACC to block excitatory impulses. This imbalance would interact with the reduced activation of the parietal-DLPC network, leading to executive dysfunction. ERP research may provide further insight regarding the temporal dynamics of action monitoring and executive functioning in OCD.