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Metazoan parasite assemblages of Pagrus pagrus inhabiting the southwestern Atlantic were analysed with the aim of identifying the existence of different stocks and to comparatively assess the value of different parasite guilds as indicators of zoogeographical regions. A total of 186 fish was examined. Samples were obtained from three Brazilian and one Argentine localities, distributed in three different biogeographic districts of the Argentine Zoogeographical Province. Pagrus pagrus harboured 26 metazoan parasite species distributed in three guilds, ectoparasites (10 species), long-lived larval endoparasites and short-lived gastrointestinal endoparasites (eight species each). Prevalence and abundance values of the former two guilds allowed analysing them comparatively to assess their value as biological indicators of both host population structure and zoogeography. Results of analyses on long-lived parasites evidenced the existence of three stocks, one in the regions of Rio de Janeiro and Sao Paulo, other in southern Brazil (Rio Grande do Sul) and a third in northern Argentina (Mar del Plata), responding to the differential environmental conditions characteristic of three zoogeographical ecoregions. Ectoparasite assemblages exhibited significant differences between all pairs of samples, including those considered as a single stock according to data on persistent parasites. Assemblages of long-lived larval parasites are considered as better indicators for stock assessment purposes than ectoparasites, whose population parameters were variable temporally and heterogeneous at small spatial scales. The distributional variability of persistent parasites of P. pagrus along large scales provides valuable information to help defining robust biogeographical patterns, applicable to stock identification and fishery management of this species.

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The high incidence of wounds by second intention and the high costs associated with their treatment give rise to the need for the development of wound dressings that protect not only the wounds themselves but that are also able to promote cell proliferation and skin regeneration. Moreover, it is also very important that no damage to the new regenerated tissue is generated while removing the dressing. In this work, a novel wound dressing, which would be able to favor tissue repair and be removed at an appropriate scheduled moment by means of an external stimulus without promoting extensive damage to the new tissue, was produced and tested. Polyurethane membranes were modified by grafting polymers based on poly(n-isopropylacrylamide) (P-N-IPAAm). P-N-IPAAm undergoes a phase transition at approximately 32°C, which changes its behavior from hydrophilic (below 32°C) to hydrophobic. It was hypothesized that, by reducing the temperature near the wound dressing to values lower than 32°C, the detachment of the dressing would become more effective. The wound dressings containing P-N-IPAAm grafts were tested in vivo by covering excisional wounds produced in mice. The produced dressings were placed in direct contact with the lesions for 3 days. Results showed that the hypothermia due to anesthesia required to remove the dressings from mice lowered the local temperature to 28°C and favored the detachment of the wound dressings containing P-N-IPAAm grafts. Histological analyses showed that lesions covered by dressings presented less intense inflammatory events and denser connective tissue than did the wounds without dressings. The wounds covered by polyurethane membranes with P-N-IPAAm grafts showed signs of more intense re-epithelization and angiogenesis than did the lesions covered by polyurethane without grafts.

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ABSTRACT FUNGI IN THE BIOREMEDIATION OF DEGRADED AREAS. The increase in industrial ac tivities has intensified environmental pollution, promoting the improper disposal of household and industrial waste, especially hazardous waste, resulting in contamination of soil, air, surface water and groundwater resources. One of the technologies used in the recovery of these degraded areas is bioremediation, which uses microorganisms as recovery agents. Therefore, this review aims to address the main aspects of bioremediation by fungi mycoremediation of contaminated soil based on various previously published studies available in major databases such as SciELO, LILACS, HighWire, PubMed. This biotechnology has been used for years in other countries, and in some cases has lower cost and higher efficiency in removal of contaminants than the physical and chemical techniques that are currently used on a commercial scale in the treatment of various wastes and the remediation of degraded areas. It is therefore necessary to develop further studies to understand the mechanisms of bioremediation mediated by microorganisms, as a biological tool in fighting pollution.

RESUMO O aumento das atividades industriais tem intensificado a poluição ambiental, promovendo a disposição inadequada de resíduos domésticos e industriais, principalmente resíduos perniciosos, implicando na contaminação do solo, ar, recursos hídricos superficiais e subterrâneos. Dentre as tecnologias mais utilizadas na recuperação dessas áreas degradadas, destaca-se a biorremediação, que tem, como agentes recuperadores, os micro-organismos. Portanto, o presente trabalho de revisão tem por objetivo abordar os principais aspectos da biorremediação por fungos micorremediação de solos contaminados baseados nas diversas pesquisas já publicadas e disponíveis nos principais bancos de dados, tais como SciELO, LILACS, HighWire e PubMed. Essa biotecnologia vem sendo utilizada há vários anos em outros países e, em certos casos, apresenta menor custo e maior eficiência na remoção dos contaminantes do que as técnicas físicas e químicas que são atualmente utilizadas em escala comercial no tratamento de diversos resíduos e na remediação de áreas degradadas. Diante disso, é necessário que sejam realizados mais estudos para compreender os mecanismos de biorremediação mediada por micro-organismos, como ferramenta biológica no combate a poluição.

RESUMO

O aumento das atividades industriais tem intensificado a poluição ambiental, promovendo a disposição inadequada de resíduos domésticos e industriais, principalmente resíduos perniciosos, implicando na contaminação do solo, ar, recursos hídricos superficiais e subterrâneos. Dentre as tecnologias mais utilizadas na recuperação dessas áreas degradadas, destaca-se a biorremediação, que tem, como agentes recuperadores, os micro-organismos. Portanto, o presente trabalho de revisão tem por objetivo abordar os principais aspectos da biorremediação por fungos ­ micorremediação de solos contaminados baseados nas diversas pesquisas já publicadas e disponíveis nos principais bancos de dados, tais como SciELO, LILACS, HighWire e PubMed. Essa biotecnologia vem sendo utilizada há vários anos em outros países e, em certos casos, apresenta menor custo e maior eficiência na remoção dos contaminantes do que as técnicas físicas e químicas que são atualmente utilizadas em escala comercial no tratamento de diversos resíduos e na remediação de áreas degradadas. Diante disso, é necessário que sejam realizados mais estudos para compreender os mecanismos de biorremediação mediada por micro-organismos, como ferramenta biológica no combate a poluição.

The increase in industrial ac tivities has intensified environmental pollution, promoting the improper disposal of household and industrial waste, especially hazardous waste, resulting in contamination of soil, air, surface water and groundwater resources. One of the technologies used in the recovery of these degraded areas is bioremediation, which uses microorganisms as recovery agents. Therefore, this review aims to address the main aspects of bioremediation by fungi ­ mycoremediation of contaminated soil based on various previously published studies available in major databases such as SciELO, LILACS, HighWire, PubMed. This biotechnology has been used for years in other countries, and in some cases has lower cost and higher efficiency in removal of contaminants than the physical and chemical techniques that are currently used on a commercial scale in the treatment of various wastes and the remediation of degraded areas. It is therefore necessary to develop further studies to understand the mechanisms of bioremediation mediated by microorganisms, as a biological tool in fighting pollution.

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