Expression of angiogenic factors in placenta of stressed rats

The aim of the present study was to analyse the influence of stress on pregnant rats, particularly in terms of maternal, placental and fetal weight, placental morphology and placental gene expression of the angiogenic factors Vegfa and Pgf and their receptors. The parameters were evaluated on gestation Day 20. Maternal, fetal and placental weights were statistically lower in stressed animals than controls, suggesting abnormalities in gestational physiology. Morphologically the placentas of rats subjected to stress were reduced in size and weight, with few glycogen cells and a significant increase in the number of apoptotic cells. Stress caused an increase in placental gene expression of Vegfa (P < 0.05) and a reduction in Pgf, Flt1 and Kdr expression (P < 0.05). It has been suggested that increased VEGF is associated with vasodilatation and hypotension, but in this model persistent hypertension was present. This study suggests that the limited hypotensive Vegfa response to stress-induced hypertension could result from reduced expression of Flt1/Kdr disrupting specific VEGF pathways. These findings may elucidate one of the multiple possible factors underlying how stress modulates placental physiology, and could aid the understanding of stress-induced gestational disorders.

A radioenzymatic assay to identify three groups of phospholipase A(2) in platelets

Phospholipases A(2) (PLA(2)) are key enzymes in membrane metabolism. The release of fatty acids and lysophospholipids by PLA(2) activates several intra-cellular second messenger cascades that regulate a wide variety of physiological responses. The aim of the present study is to describe a radioenzymatic assay to determine the activity of three main PLA(2) subtypes in platelets, namely extracellular calcium-dependent PLA(2) (sPLA(2)) and intracellular calcium-dependent (cPLA(2)) and calcium-independent PLA(2) (iPLA(2)). The differentiation of these distinct PLA(2) subtypes was based on the enzyme substrate preference (arachdonic acid or palmitoyl acid) and calcium concentration. Our results indicate that this new assay is feasible, precise and specific to measure the activity of the aforementioned subtypes of PLA(2). Therefore, this protocol can be used to investigate modifications of PLA(2) homeostasis in distinct biological models addressing the pathophysiology of many medical and neuropsychiatric disorders such as schizophrenia and Alzheimer's disease. (C) 2012 Elsevier Ltd. All rights reserved.

Regulation of neurogenesis and gliogenesis of retinoic acid-induced P19 embryonal carcinoma cells by P2X2 and P2X7 receptors studied by RNA interference

Embryonic carcinoma cells are widely used models for studying the mechanisms of proliferation and differentiation occurring during early embryogenesis. We have now investigated how down-regulation of P2X2 and P2X7 receptor expression by RNA interference (RNAi) affects neural differentiation and phenotype specification of P19 embryonal carcinoma cells. Wild-type P19 embryonal carcinoma cells or cells stably expressing shRNAs targeting P2X2 or P2X7 receptor expression were induced to differentiate into neurons and glial cells in the presence of retinoic acid. Silencing of P2X2 receptor expression along differentiation promoted cell proliferation and an increase in the percentage of cells expressing glial-specific GFAP, while the presence of beta-3 tubulin-positive cells diminished at the same time. Proliferation induction in the presence of stable anti-P2X2 receptor RNAi points at a mechanism where glial proliferation is favored over growth arrest of progenitor cells which would allow neuronal maturation. Differently from the P2X2 receptor, inhibition of P2X7 receptor expression during neural differentiation of P19 cells resulted in a decrease in cell proliferation and GFAP expression, suggesting the need of functional P2X7 receptors for the progress of gliogenesis. The results obtained in this study indicate the importance of purinergic signaling for cell fate determination during neural differentiation, with P2X2 and P2X7 receptors promoting neurogenesis and gliogenesis, respectively. The shRNAs down-regulating P2X2 or P2X7 receptor gene expression, developed during this work, present useful tools for studying mechanisms of neural differentiation in other stem cell models. (C) 2012 ISDN. Published by Elsevier Ltd. All rights reserved.

Antioxidant and inflammatory aspects of lipoprotein-associated phospholipase A2 (Lp-PLA2 ): a review

The association of cardiovascular events with Lp-PLA2 has been studied continuously today. The enzyme has been strongly associated with several cardiovascular risk markers and events. Its discovery was directly related to the hydrolysis of the platelet-activating factor and oxidized phospholipids, which are considered protective functions. However, the hydrolysis of bioactive lipids generates lysophospholipids, compounds that have a pro-inflammatory function. Therefore, the evaluation of the distribution of Lp-PLA2 in the lipid fractions emphasized the dual role of the enzyme in the inflammatory process, since the HDL-Lp-PLA2 enzyme contributes to the reduction of atherosclerosis, while LDL-Lp-PLA2 stimulates this process. Recently, it has been verified that diet components and drugs can influence the enzyme activity and concentration. Thus, the effects of these treatments on Lp-PLA2 may represent a new kind of prevention of cardiovascular disease. Therefore, the association of the enzyme with the traditional assessment of cardiovascular risk may help to predict more accurately these diseases.

Insatisfação corporal, prática de dietas e comportamentos de risco para transtornos alimentares em mães residentes em Santos

OBJETIVO: Avaliar a insatisfação corporal, a prática de dietas e os comportamentos de risco para transtornos alimentares em uma amostra de mães residentes no município de Santos. MÉTODOS: Foi realizado um estudo transversal, de base populacional, com 453 mães de filhos com até 10 anos de idade. As mães responderam ao Teste de Atitudes Alimentares (EAT-26), à Escala de Figuras de Stunkard e a uma questão sobre a prática atual de dietas. RESULTADOS: Das mães, 29,9% apresentaram escore positivo para os comportamentos de risco para transtornos alimentares e 21,8% estavam fazendo dieta para emagrecer no momento da entrevista. No tocante à imagem corporal, 17,5% das mães estavam satisfeitas com o seu tamanho corporal, 71,5% gostariam de diminuir seu tamanho corporal e 11,0% gostariam de aumentá-lo. Os comportamentos de risco para transtornos alimentares foram mais frequentes nas mães insatisfeitas com seus tamanhos corporais (p < 0,0001). CONCLUSÃO: A maioria das mães investigadas estava insatisfeita com os seus tamanhos corporais. A frequência de mães que praticavam dietas ou tinham comportamentos de risco para transtornos alimentares foi similar ou superior aos demais estudos nacionais, conduzidos, em sua maioria, com populações consideradas de risco, como meninas adolescentes e jovens universitárias.

Zearalenone, an estrogenic mycotoxin, is an immunotoxic compound

The aim of this study was to assess the toxic effects of zearalenone (ZEA) on the immune function. Ovariectomised rats were treated daily by gavage with 3.0 mg/kg of ZEA for 28 days. Body weight gain, food consumption, haemotological parameters, lymphoid organs, and their cellularities were evaluated. Moreover, acquired immune responses and macrophage activity were also assessed. ZEA promoted reduction in body weight gain, which is not fully explained by diminished food consumption. Despite no effect on haematological parameters, ZEA caused thymic atrophy with histological and thymocyte phenotype changes and decrease in the B cell percentage in the spleen. With respect to acquired and innate immune responses, no statistically significant differences in delayed-type hypersensitivity were noticed; however, in the ZEA-treated rats, antibody production and peroxide release by macrophages were impaired. The observed results could be related to ZEA activity on ERs; thus, ZEA is an immunotoxic compound similar to estrogen and some endocrine disruptors.

Referencing geostrophic velocities using ADCP data at 24.5 ºN

Diploma de Estudios Avanzados

Mujer y Romancero: claves del protagonismo femenino en el género romancístico

Reúne esta intervención, someramente expuestas, algunas de las conclusiones de la Tesis doctoral de la autora denominada "Formas y funciones del personaje mujer en el Romancero tradicional (Sobre el ejemplo del Romancero de Gran Canaria)", obra digitalizada, ISBN: 9788469170854 (Repositorio institucional ULPGC). El repertorio romancístico analizado evidencia el enorme interés por plasmar el mundo personal, especialmente desde la óptica sentimental, de las protagonistas femeninas de los relatos.

Referencing geostrophic velocities using ADCP data at 24.5°N (North Atlantic)

[EN] Acoustic Doppler Current Profilers (ADCPs) have proven to be a useful oceanographic tool in the study of ocean dynamics. Data from D279, a transatlantic hydrographic cruise carried out in spring 2004 along 24.5°N, were processed, and lowered ADCP (LADCP) bottom track data were used to assess the choice of reference velocity for geostrophic calculations. The reference velocities from different combinations of ADCP data were compared to one another and a reference velocity was chosen based on the LADCP data. The barotropic tidal component was subtracted to provide a final reference velocity estimated by LADCP data. The results of the velocity fields are also shown. Further studies involving inverse solutions will include the reference velocity calculated here.

The Azores Current System and the Canary Current from CTD and ADCP data

Se han eliminado páginas en blanco

La aparicion de los misterios mitraicos en el marco religioso del Imperio Romano

[ES] El dios Mitra procedía del panteón iranio, donde era adorado como protector de los contratos y de los juramentos. En el siglo I d.c. aparece su culto dentro de las fronteras del Imperio Romano asociado a unas prácticas religiosas enmarcadas dentro de la nueva religiosidad que impera en ese momento. Mitra, junto con Isis o Cibeles, recibe un culto mistérico encaminado a proporcionar una experiencia particular y escatológica a los fieles que sean iniciados en su adoración. Se describen en este artículo los elementos que definen estas religiones denominadas mistéricas y el papel desempeñado por el Mitraísmo en el marco religioso romano del Alto Imperio

La tetralogía de Ramón Pérez de Ayala : aspectos ético-estéticos, lectorales y genéricos

Programa de Doctorado: Filología Hispánica

El ilustrado canario José Viera y Clavijo (1731-1813) y su afición por las ciencias

[ES] La conferencia estará centrada en la trayectoria intelectual del ilustrado y polifacético canario José de Viera y Clavijo, con el fin de conocer a fondo su vertiente científica. En ella se dará una visión general del personaje, mencionando todos los campos que abordó a lo largo de su vida. Se analizarán someramente los distintos aspectos científico-naturalistas tratados por él, tanto en sus estudios como en su producción: astronómicos, físicos, químicos, geológicos, botánicos, zoológicos, agrícolas, geográficos y ecológicos.

El eterno devenir de la existencia humana en el film Despedidas de Yojiro Takita

[ES] Este artículo pretende abordar las interrelaciones simbólicas existentes entre la vida y la muerte en la película Despedidas del director japonés Yojiro Takita. El protagonista de este filme es un joven que abandona su trabajo como violonchelista y se convierte en “nokanshi”, amortajador profesional. A través de su trabajo, este personaje descubre la muerte en todas sus facetas, lo que le permite comenzar una nueva etapa en su vida y al mismo tiempo encontrar en este oficio una forma de realización personal.