Effects of microplastics on key reproductive and biochemical endpoints of the freshwater microcrustacean Daphnia magna.

Human activities have directly impacted the environment, causing significant ecological imbalances. From the different contaminants resulting from human activities, plastics are of major environmental concern. Due to their high use and consequent discharge, plastics tend to accumulate in aquatic environments. There, plastics can form smaller particles (microplastics, MPs), due to fragmentation and weathering, which are more prone to interact with aquatic organisms and cause deleterious effects, including at the basis of different food webs. This study assessed the effects of two microplastics (polyethylene terephthalate, PET; and polypropylene, PP; both of common domestic use) in the freshwater cladoceran species Daphnia magna. Toxic effects were assessed by measuring reproductive traits (first brood and total number of offspring), and activities of biomarkers involved in xenobiotic metabolism (phase I: cytochrome P-450 isoenzymes CYP1A1, 1A2 and 3A4; phase II/conjugation: glutathione S-transferases; and antioxidant defense (catalase)). Both MPs showed a potential to significantly reduce reproductive parameters in D. magna. Furthermore, PET caused a significant increase in some isoenzymes of CYP450 in acutely exposed organisms, but this effect was not observed in chronically exposed animals. Similarly, the activity of the antioxidant defense (CAT) was significantly increased in acutely exposed animals, but not in chronically exposed organisms. This pattern of effects suggests a possible mechanism of long-term adaptation to the presence of the tested MPs. In conclusion, the herein tested MPs have shown the potential to induce deleterious effects on D. magna mainly observed in terms of the reproductive outcomes. Changes at the biochemical level seems transient and are not likely to occur in long term, environmentally exposed crustaceans.

Evolução da força de trabalho em enfermagem no município de Uberlândia no período de 1994 a 2002 / Changes in nursing staff in the town of Uberlândia, state of Minas Gerais, Brazil from 1994 to 2002 / Evolución de la fuerza de trabajo en enfermería en la ciudad de Uberlandia de 1994 a 2002

Este estudo apresenta a evolução da força de trabalho da enfermagem em Uberlândia-MG, no período de 1994 a 2002. Buscou caracterizar as mudanças de aspectos relevantes ocorridas nos últimos oito anos. Os dados foram colhidos por meio de um formulário preenchido pelos profissionais das diversas instituições. Dentre as principais conclusões se destacam as seguintes: crescimento no número de enfermeiros, técnicos e auxiliares e decréscimo no de atendentes; manutenção da prevalência feminina; maior inserção de profissionais jovens; o setor público é o maior empregador; existem poucos profissionais irregulares com o COREN-MG; melhoria na titulação dos enfermeiros; aumento do duplo vínculo; rotatividade estável.

This study examines the Nursing personnel in the town of Uberlândia, state of Minas Gerais, Brazil, in the period from 1994 to 2002. It intends to describe relevant changes that occurred during these eight years. The data was collected through a form filled out by nurses in various institutions. Some of the main conclusions: growth of the number of nurses, nursing technicians and nursing auxiliaries, and reduction of the number of "nursing attendants"; prevalence of women continues; greater number of young workers; public sector is greatest employer; there are few nurses not properly registered with the official licensing agency - COREN-MG; nurses are better qualified; more workers have more than one job; turnover is unaltered.

Este análisis, que muestra la evolución de la fuerza de trabajo de enfermería en Uberlândia, Estado de Minas Gerais, entre 1994 y 2002, busca caracterizar los cambios de aspectos relevantes durante los últimos ocho años. Los datos se recopilaron en una planilla completada por profesionales de distintas instituciones. Entre las principales conclusiones se destacan: aumenta el número de enfermeros, técnicos y auxiliares y disminuye el de ayudantes; se mantiene la preponderancia femenina; más inserción de profesionales jóvenes; el sector público es el principal empleador; pocos profesionales en situación irregular con COREN-MG; mejora la titulación de los enfermeros; aumenta el doble vínculo laboral y se mantiene estable la rotatividad..