13 research outputs found

    Oxidative stress in pregnancy and fertility pathologies

    Get PDF
    Oxidative stress designates the state of imbalance between reactive oxygen species (ROS) production and antioxidant levels. In a healthy placenta, there is an increase in ROS production, due to formation of new tissues and inherent metabolism, but this is balanced by higher levels of antioxidants. However, this balance is lost in some situations, with a consequent increase in oxidative stress levels. Oxidative stress has been implicated in several placental disorders and pregnancy pathologies. The present review intends to summarize what is known about the relationship between oxidative stress and well-known pregnancy disorders

    Hidrófitas fanerogâmicas de ecossistemas aquáticos temporários da planície costeira do Estado do Rio de Janeiro, Brasil Phanerogamic hydrophytes from the temporary swampy environments of coastal plains of northern Rio de Janeiro State, Brazil

    No full text
    Foi realizado o levantamento florístico das hidrófitas fanerogâmicas de ambientes aquáticos temporários da planície costeira do norte fluminense. O material botânico foi coletado em 27 expedições entre setembro/1998 a julho/2001, herborizado e identificado segundo a metodologia tradicional. As exsicatas foram depositadas no Herbário da Universidade do Rio de Janeiro (HUNI). Foram encontrados 113 táxons, distribuídos em 40 famílias. Os ambientes estudados podem ser caracterizados floristicamente pela família Cyperaceae, representada por 23 táxons (cerca de 20%); seguida pelas famílias Fabaceae e Onagraceae (sete táxons), Poaceae (seis táxons), Asteraceae e Scrophulariaceae (cinco táxons) e Apiaceae, Lentibulariaceae e Polygonaceae (quatro táxons). Estes ambientes sofrem alterações fitofisionômicas marcantes relacionadas com a hidrogeologia. Algumas espécies são anuais, desaparecendo completamente na estiagem; outras suportam a seca, mas têm a população profundamente reduzida, alterando substancialmente a paisagem. Algumas espécies consideradas exclusivamente aquáticas foram encontradas em solo úmido, inclusive em floração. Isto demonstra a necessidade da inclusão de espécies anfíbias nos estudos da flora aquática pois, algumas vezes, a delimitação dos tipos biológicos não é muito definida, além de caracterizar de forma mais adequada estes ambientes.<br>A floristic inventory of phanerogamic hydrophytes from the temporary swampy environments of coastal plains of northern of Rio de Janeiro State was made. The botanical vouchers were collected in 27 expeditions between September/1998 and July/2001. They were herborized and identified by the traditional methodology. The exsicatae were deposited in the UNIRIO herbarium (HUNI). One hundred and thirteen taxa, distributed among 40 families were found. The environment analyzed could be floristically characterized by the Cyperaceae, represented by 23 taxa (ca. 20%), followed by Fabaceae and Onagraceae (seven taxa), Poaceae (six taxa), Asteraceae and Scrophulariaceae (five taxa) and Apiaceae, Lentibulariaceae and Polygonaceae (four taxa). These environments have great phytophysionomic changes according to hydrogeology. Some species are annual, disappearing completely in the dry season; another species tolerates the dryness but the population reduce drastically, changing substantially the landscape. Some species regarded as strictly aquatic were found in humid soil, producing flowers. This shows the necessity to include amphibious species on the aquatic flora studies because sometimes the boundaries between the biological types were not well defined
    corecore