http://www.recercat.cat:80/handle/2072/179320 Thu, 20 Jun 2013 06:42:02 GMT 2013-06-20T06:42:02Z http://www.recercat.cat:80/bitstream/id/44942/ http://www.recercat.cat:80/handle/2072/179320 http://www.recercat.cat:80/handle/2072/202533 Heavy metal accumulation by intestinal helminths of vertebrates Torres Martínez, Jordi; Eira, Catarina; Miquel Colomé, Jordi; Feliu José, Carlos The relevancy of parasites as potential indicators of environmental quality has been increasing over the last years, mostly due to the variety of ways in which they respond to anthropogenic pollution. The use of fish parasites as bioindicators of heavy metal pollution in aquatic ecosystems has been widely studied. However, little information concerning terrestrial habitats is presently available. In fact, in the last two decades several studies have been performed worldwide in different habitats and/or conditions (theoretically both in polluted and unpolluted terrestrialecosystems, but mainly in aquatic ecosystems) in order to investigate heavy metal pollution using parasitological models. Different groups of vertebrates (mainly fish, mammals and birds) and several parasitological models have been tested involving acanthocephalans mostly, but also cestodes and nematodes. It is not the aim of this chapter to do a complete revision of the availabledata concerning this subject. Instead, we emphasize some general aspects and compile a mini-review of the work performed in this field by our research group. The results obtained until now allow confirming several parasitic models as promising bioindicator systems to evaluate environmental cadmium and mainly lead pollution in terrestrial non-urban habitats, as it was already demonstrated for aquatic ecosystems. The present knowledge also allows confirming that parasites can reveal environmental impact. Environmental parasitology is an interdisciplinary field, which needs simultaneous expertise from toxicology, environmental chemistry and parasitology. Furthermore, environmental parasitology should be taken into account in order to increase the efficiency of environmental monitoring programs. http://www.recercat.cat:80/handle/2072/202533 http://www.recercat.cat:80/handle/2072/202158 Advances in the research of new biosurfactants and their potential use in the biomedical and pharmaceutical industry Burgos-Díaz, César; Piqué i Clusella, Núria; Manresa Presas, Ma. Ángeles (María Ángeles); Marqués Villavecchia, Ana Ma. Biosurfactants (BS) are a structurally diverse group of surface-active substances produced by microorganisms. Interest inBS production has markedly increased during the past decade, although large-scale production has not been possible because oflow production yields and high total costs. At present, BS have gained importance in environmental applications, while newapplications in the pharmaceutical, biomedical, cosmetic and foodindustry, with a high added value, are still developing. This article describes classical and new BS producer bacteria together withtheir new BS applications. With these specialized and costeffectiveapplications, BS can be considered as an interesting option for the near future. http://www.recercat.cat:80/handle/2072/202158 http://www.recercat.cat:80/handle/2072/179521 Cryptosporidium sp. in public swimming pools in Barcelona Gómez, María Soledad; Gracenea Zugarramurdi, Mercedes; Ángel Ripoll, Laia; Beneyto, Vicenç The presence of Cryptosporidium oocysts in swimming pools in Barcelona was studied. The possible influence of the different parameters related to water conditions, pool structure and users has also been analyzed. Cryptosporidium oocysts were detected in 54% of the swimming pools analyzed and in 85% of the sport centers checked. Oocysts concentrations ranged from 0 to 30 oocysts/L. Among parameters related to water conditions, there was no relationship between oocyst presence and water pH, but the influence of temperature was statistically significant (p"MENOR QUE"0.05) (¿2=0.024). Among parameters related to pool structure, the filter backwash water samples revealed a higher percentage of parasitation (58.8%) than the prefilter ones (42.9%). With the medium volume pools (100-500 m3), the percentage was higher (80%). Covered and uncovered pools presented similar prevalences for Cryptosporidium oocysts. Looking at two of the user related parameters, swimming pools with more users and children's swimming pools showed http://www.recercat.cat:80/handle/2072/179521 http://www.recercat.cat:80/handle/2072/179520 Crystallization and resolution of the lipoxygenase of Pseudomonas aeruginosa 42A2 and phylogenetic study of the subfamilies of the lipoxygenases Garreta, Albert; Carpena i Vilella, Xavi; Busquets Abió, Montserrat; Fusté Munné, M. Carme; Fita Rodríguez, Ignasi; Manresa Presas, Ma. Ángeles (María Ángeles) Lipoxygenases are non-heme iron enzymes essential in eukaryotes, where they catalyze the formation of the fatty acid hydroperoxides that are required by a large diversity of biological and pathological processes. In prokaryotes, most of them totally lacking in polyunsaturated fatty acids, the possible biological roles oflipoxygenases have remained obscure. In this study, it is reported the crystallization of a lipoxygenase of Pseudomonas aeruginosa (Pa_LOX), the first from a prokaryote. High resolution data has been acquired which is expected to yield structural clues to the questions adressed. Besides, a preliminar phylogenetic analysis using 14 sequences has confirmed the existence of this subfamily of bacterial lipoxygenases, on one side, and a greater diversity than in the corresponding eukaryotic ones, on the other. Finally, an evolutionary study of bacteriallipoxygenases on the same set of lipoxygenases, show a selection pressure of a basically purifying or neutral character except for a single aminoacid, which would have been selected after a positive selection event.; Podeu consultar el llibre complet a: http://hdl.handle.net/2445/32392 http://www.recercat.cat:80/handle/2072/179520