Fundação de Amparo a Pesquisa no Estado do Rio Grande do Sul / On the last decades, amphibian populations have been suffering a global decline, and different factors can be related to this process. Parallel observations between the decrease of stratospheric ozone concentration in the late 1970s and amphibian decline in early 1980s aroused interest to study the possible association among increased incidence of ultraviolet radiation (UV) and amphibian decline. The UV radiation has important biological impact on living organisms due to their ability to induce lesions in the DNA molecule, which may result in the induction of mutations or cell death. Photoreactivation is an important DNA repair mechanism that promotes the reversal of UV-induced DNA damage by photolyase enzymes after the absorption of UVA and visible light photons. In this study, we evaluated the biolocial effects of UVB and UVA through morphological, histological, locomotor and survival of Hypsiboas pulchellus (Anura: Hylidae) tadpoles. Tadpoles kept in the laboratory were submitted to acute and chronic treatments, composed of different doses of UVB and UVA exposures. The results of survival curves indicate that the H. pulchellus is very sensitive to UVB radiation comparative to UVA. However, despite the high tadpole survival after UVA, they showed serious malformations after metamorphosis. Tadpoles body weight also suffered influence of different UV radiation doses, however the body length was bit affected. The locomotor capacity (horizontal and vertical speed) of UVB-exposed tadpoles has been significantly changed. In addition, UVB radiation had severe impact on the skin (stratum corneum) and mouth (rows of teeth and jaw sheaths) keratin structures of tadpoles, indicating that these should be important impacts of solar UV radiation in reducing the performance of these organisms. In parallel, it was also possible to observe the extreme importance of activation of photolyases for the repair of DNA damage after treatment with UVB but not UVA. Therefore, in this study, we present a wide characterization of the biological effects of solar UVB and UVA on the performance of H. pulchellus tadpoles. / Durante as últimas décadas, as populações de anfíbios vêm sofrendo um declínio generalizado e diferentes fatores são sugeridos como responsáveis por esse efeito. Observações paralelas entre o rápido decréscimo da concentração do ozônio estratosférico no final da década de 1970, com o declínio de anfíbios no início da década de 1980, despertaram grande interesse para se estudar as possíveis associações entre o aumento da incidência de radiação ultravioleta (UV) na superfície e a redução do número de espécies de anfíbios. Sabe-se que a radiação UV solar tem importante impacto biológico na vida dos organismos devido a sua grande capacidade de induzir lesões na molécula de DNA, que podem levar a indução de mutações ou morte celular. Um dos principais mecanismos de reparo de DNA é a fotorreativação que ocorre por meio das enzimas fotoliases, as quais promovem reversão dessas lesões ao absorver fótons de luz UVA e luz visível. Neste projeto, avaliou-se a ação biológica da radiação UVB e UVA a partir de dados morfológicos, histológicos, locomotores e de sobrevivência de girinos da espécie Hypsiboas pulchellus (Anura: Hylidae). Girinos coletados e mantidos no laboratório foram submetidos a tratamentos agudos e crônicos, compostos por exposições a diferentes doses de luz UVB e UVA. Os resultados de sobrevivência indicam que os girinos de H. pulchellus são muito sensíveis à radiação UVB em relação à UVA. Entretanto, apesar da alta sobrevivência dos indivíduos submetidos à radiação UVA, estes apresentaram sérias malformações em longo prazo. A massa corporal dos girinos também sofreu influência das diferentes doses de radiação UV aplicadas, entretanto o comprimento total foi pouco influenciado. A capacidade locomotora (vertical e horizontal) dos organismos expostos à luz UV foi bastante alterada, onde se destaca a grave redução da atividade locomotora dos indivíduos tratados com radiação UVB. Adicionalmente, a radiação UVB teve impacto severo nas estruturas de queratina da pele (estrato córneo) e da boca (queratodontes e mandíbula) dos girinos, indicando que esses devem ser impactos principais da radiação UV solar na redução da performance desses organismos. Em paralelo, também foi possível observar a extrema importância da ativação das enzimas fotoliases para a reparação dos danos de DNA, assim como os seus efeitos após os tratamentos com radiação UVB, mas não com UVA. Portanto, no presente trabalho, foi possível apresentar uma ampla caracterização dos efeitos biológicos da radiação UVB e UVA solar na performance de girinos de H. pulchellus.

Submitted by Simone Souza (simonecgsouza@hotmail.com) on 2017-06-27T16:05:01Z No. of bitstreams: 1 DISS_2014_Debora Dutra Pinheiro.pdf: 3947317 bytes, checksum: 0edc41cec3b2b34e95c3eb17e581e4ff (MD5) / Approved for entry into archive by Jordan (jordanbiblio@gmail.com) on 2017-06-28T16:44:36Z (GMT) No. of bitstreams: 1 DISS_2014_Debora Dutra Pinheiro.pdf: 3947317 bytes, checksum: 0edc41cec3b2b34e95c3eb17e581e4ff (MD5) / Made available in DSpace on 2017-06-28T16:44:36Z (GMT). No. of bitstreams: 1 DISS_2014_Debora Dutra Pinheiro.pdf: 3947317 bytes, checksum: 0edc41cec3b2b34e95c3eb17e581e4ff (MD5) Previous issue date: 2014-09-29 / A Educação de Jovens e Adultos configurou-se ao longo do tempo como meio de fornecer as pessoas, que não tiveram oportunidade de iniciar, ou progredir, seus estudos, retornarem a escola para aprimorarem e efetivarem seu direito a educação. Historicamente os alunos desta modalidade educativa são do proletariado e, em sua maioria, buscavam a alfabetização. É mandatório oferecer, não só, aos alunos da educação de jovens e adultos a alfabetização, mas também um ensino médio de qualidade, com as metodologias e práticas educacionais voltadas para a modalidade. O produto educacional “Sapiando” foi elaborado para fornecer ao professor de Biologia arcabouço teórico e didático para o ensino da anfibiofauna, conteúdo referente ao currículo do ensino médio. Além de propor um produto educacional na teoria da aprendizagem significativa, foi realizado neste trabalho um levantamento histórico sobre a modalidade , além dos dados sobre o estado da arte das pesquisas sobre o ensino de Biologia. Com os resultados obtidos a partir das análises qualitativas dos dados oriundos da aplicação do produto “Sapiando” inferimos que o produto educacional contribui efetivamente para a aprendizagem significativa. / The young and adult education established across time, as a mean to provide to people that did not had opportunity to start or progress their studies, to return to school to improve and actualize their right to education. Historically, the students of this educational method are workers and often sought literacy. Is required to provide both literacy and a good high school, with specific methodologies and educational practices. In this work it was proposed an educational product grounding in the andragogy principles and in the significantly learning theory . The educational product “Sapiando” was produced to give to the teacher of Biology a theoretical and didactic framework to the instruction about the amphibian fauna, content of the high school curriculum. Furthermore, a historical review and the state of art of Biology teaching research was evaluated. With the qualitative analysis of the results of “Sapiando” application in the classroom, it is possible to infer that the educational product effectively contribute to the significantly learning.

Submitted by Mario BC (mario@bc.ufrpe.br) on 2016-08-12T12:35:52Z No. of bitstreams: 1 Narciso Silva Leite Junior.pdf: 964909 bytes, checksum: d234d1169d74d0400bfd6c1088a39c58 (MD5) / Made available in DSpace on 2016-08-12T12:35:52Z (GMT). No. of bitstreams: 1 Narciso Silva Leite Junior.pdf: 964909 bytes, checksum: d234d1169d74d0400bfd6c1088a39c58 (MD5) Previous issue date: 2012-02-10 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The Atlantic forest is the biome with the greatest concentration of endemic species in the world and is under severe threat of extinction. In the group of vertebrates amphibians occupy a prominent place in the number of endemism, with more than half of all species as being unique to that biome. The study was conducted in the Reserva Estadual de Gurjaú (RESG), which is located south of the city of Recife, within the limits of three municipalities (Jaboatão dos Guararapes, Cabo de Santo Agostinho and Moreno). The RESG has a total area of 1,077.10 ha, of which 400 ha are made up of forest areas. Since its inception Pernambuco is administered by the Company of Water and Sanitation (COMPESA), which has a treatment plant installed in the reserve while eliminating its chemical waste downstream of water intake. The frogs during their life cycle are subject to exposure in various types of environment, opposite as important bioindicators of polluted areas and environmentally abused. In order to confirm the harmful effect of disposing of waste in the environment, between January and December 2004 were collected weekly by active search in a 1km stretch of the River Gurjaú, 500m and 500m upstream and downstream of the point of eliminating pollutants. The results show that the 25 species listed for the RESG, six were seen near the river, namely: Hypsiboas semilineatus (Spix, 1824), Leptodactylus gr. marmoratus (Steindachner, 1867), Scinax x-signatus (Spix, 1824), Lithobates palmipes (Spix, 1824), Leptodactylus vastus (Spix, 1824) and Pseudopaludicola gr. falcipes (Hensel, 1867). Comparing the frequency of species in sampling sites with data from biochemical analysis of the water, we can conclude that the discharge of waste made COMPESA characterized by a potentially harmful action to the environment. / Os anfíbios anuros durante seu ciclo de vida estão sujeitos a exposição em diversos tipos de ambientes, contracenando como importantes bioindicadores de áreas poluídas e ambientalmente agredidas. No grupo dos vertebrados, os anfíbios ocupam lugar de destaque em relação ao número de endemismo, apresentando mais de metade do total de espécies como sendo exclusivas do bioma brasileiro mata atlântica. Objetivando confirmar o efeito nocivo da eliminação dos dejetos no ambiente, entre janeiro e dezembro de 2004 foram realizadas coletas semanais por busca ativa, em uma extensão de um (1) km à margem do Rio Gurjaú, sendo 500m a montante e 500m a jusante do ponto de eliminação dos poluentes. O trabalho foi desenvolvido na Reserva Estadual de Gurjaú (RESG), que está localizada ao sul da cidade do Recife, dentro dos limites de três municípios (Jaboatão dos Guararapes, Cabo de Santo Agostinho e Moreno). A RESG possui uma área total de 1.077,10 ha, dos quais 400 ha são compostos por áreas de floresta. Desde a sua criação é administrada pela Companhia Pernambucana de Saneamento e Águas (COMPESA), a qual possui uma estação de tratamento instalada na reserva, que elimina seus dejetos químicos a jusante da captação de água. Os resultados mostram que das 25 espécies listadas para a RESG, seis foram observadas nas proximidades do rio, a saber: Hypsiboas semilineatus (Spix, 1824), Leptodactylus gr. marmoratus (Steindachner, 1867), Scinax x-signatus (Spix, 1824), Lithobates palmipes (Spix, 1824), Leptodactylus vastus (Spix, 1824) e Pseudopaludicola gr. falcipes (Hensel,1867). Comparando a frequência das espécies nos pontos amostrados com os dados de análises bioquímicas da água, podemos concluir que a descarga de resíduos efetuada pela COMPESA caracteriza-se uma ação potencialmente danosa ao ambiente.

Orientadores: Paulo Inacio de Knegt Lopez de Prado, Carlos Roberto Sorensen Dutra da Fonseca / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-08T17:25:56Z (GMT). No. of bitstreams: 1 Becker_CarlosGuilherme_M.pdf: 2929831 bytes, checksum: 6d4d242a4fbe6aac18c4546b538bce05 (MD5) Previous issue date: 2007 / Resumo: O nicho dos anfíbios muda drasticamente ao longo da ontogenia, forçando larvas e pós-metamórficos a ocuparem dois hábitats distintos. Em áreas desmatadas, sítios reprodutivos aquáticos e fragmentos florestais podem ser muito desconectados, isolando o hábitat dos girinos do hábitat dos adultos, em um padrão de fragmentação que chamamos de desconexão de hábitats. Neste estudo, avaliamos os impactos da desconexão de hábitats sobre os anfíbios (i) através de migrações reprodutivas e de padrões de abundância populacional dos anfíbios com larva aquática entre fragmentos com e sem riachos em uma paisagem fragmentada de Mata Atlântica; (ii) através do uso diferencial de hábitat por diferentes guildas nesta mesma paisagem; (iii) por meio de uma análise macroecológica avaliando o efeito da desconexão entre riachos e fragmentos florestais sobre anfíbios de serrapilheira ao longo de 13 pontos na Mata Atlântica. Em nível populacional, detectamos um forte padrão de migração dos anfíbios florestais com desenvolvimento larval aquático entre fragmentos sem riachos e os riachos da matriz de pastagem. Estas espécies foram dramaticamente mais abundantes em fragmentos com riachos do que sem riachos. A estrutura de comunidades variou consistentemente entre hábitats, sendo a guilda das espécies florestais de desenvolvimento larval aquático a mais prejudicada pela desconexão. Tratando-se de grande escala geográfica, a desconexão de hábitat foi o único atributo da paisagem afetando negativamente a riqueza de espécies com desenvolvimento larval aquático, enquanto que a perda de habitat teve influência negativa somente nas espécies com desenvolvimento direto. Estes resultados sugerem que paisagens com altas taxas de desconexão entre fragmentos florestais e sítios reprodutivos têm maior chance de sofrerem declínios populacionais, especialmente de anfíbios associados à floresta e com desenvolvimento larval aquático. Estratégias de conservação em qualquer país devem considerar o fortalecimento das leis, tendo em mente a importância das matas de galeria e a configuração de cada paisagem, minimizando a desconexão entre hábitats florestais e os sítios reprodutivos dos anfíbios / Abstract: The niche of amphibians changes drastically along the ontogeny, forcing larvae and post-metamorphics to occupy two distinct habitats. In deforested areas, aquatic breeding sites and forest fragments can be far apart, isolating the habitat of tadpoles from the habitat of adults, in a landscape pattern we call habitat-split. In this study, we evaluated the impacts of habitat-split on amphibians (i) through breeding migrations and abundance patterns of species with aquatic larvae between fragments with and without streams in a severely fragmented landscape of Brazilian Atlantic Forest; (ii) by the habitat use of different guilds in this landscape; (iii) through a macroecological analysis, evaluating the effect of habitat-split on litter-amphibians throughout 13 Atlantic Forest sites. At the population level, we detected a migration pattern for the stream-breeding forest amphibians between the fragments without streams and the streams of adjacent grass fields. These species were dramatically more abundant in fragments with streams than in fragments without streams. The community structure varied consistently across habitats, being the guild of forest-associated species with aquatic larvae the most affected by habitat-split. At a larger geographic scale, habitat-split was the only landscape attribute negatively affecting the richness of species with aquatic larval stage, whereas habitat loss had negative influences on direct development species only. These results suggest that landscapes with high mismatches between forest fragments and breeding sites are more prone to experience population declines, especially of forest-associated amphibians with aquatic larval stage. Conservation strategies in any country must regard the law reinforcement, considering the importance of riparian buffers and the configuration of each landscape, minimizing the mismatch between non-reproductive habitats and breeding sites for amphibians / Mestrado / Ecologia / Mestre em Ecologia

Dans un contexte de changement climatique, il est essentiel de prévoir comment les organismes peuvent être affectés dans leurs relations physiques avec l'environnement. Les amphibiens représentent le groupe des vertébrés le plus sensible aux changements environnementaux, en raison d'une perte en eau par évaporation transépidermique (PEET) permanente. Ma thèse vise à mettre en place des approches pour mesurer et modéliser avec précision les surfaces de la peau contribuant à la PEET; établir les lois de transfert d'eau amphibien-environnement; et fournir une meilleure compréhension des réponses physiologiques face au pathogène Batrachochytrium dendrobatidis. Ces expériences ont été réalisées sur des tritons palmés (Lissotriton helveticus) mâles adultes en phase terrestre. Nos résultats suggèrent que L. helveticus ne présente aucune adaptation physiologique pour limiter la PEET, les moyens étant limités à l'expression d'une posture en forme de "$". Une méthode de reconstruction 3D basée sur l'lmagerie par Résonance Magnétique a été utilisée pour générer des géométries 3D des tritons utilisables pour mesurer leur surface, et à des fins de simulation. Nous avons ainsi réalisé une analyse numérique en 3D des PEET, et avons proposé une relation pour estimer cette perte dans une large gamme de conditions climatiques. Enfin, nos résultats supportent l'hypothèse de dysfonctionnement épidermique, suggérant que B. dendrobatidis compromet la capacité des amphibiens à se réhydrater. Ma thèse devrait contribuer à développer de nouvelles approches en sciences des relations eau-amphibiens, et à améliorer nos connaissances sur les effets des changements environnementaux sur les organismes / Ln a context of climate change, it is critical to predict how organisms might be affected in their physical relations with environment. Amphibians are among the vertebrate groups the most affected by ecological changes, because of permanent transepidermal evaporative water loss (TEWL) through their skin. My thesis aims at setting up approaches to measure and model accurately the functional skin surface areas that contribute to TEWL, establishing laws of water transfer between an amphibian and its physical environment, and providing understanding on physiological responses to the skin pathogen Batrachochytrium dendrobatidis. We conducted experiments on adult males of the palmate newt (Lissotriton helveticus) during their terrestrial phase. Our results suggest that L. helveticus did not show any physiological adaptations to restrain TEWL. The ways to reduce TEWL result essentially in the expression of a stereotyped "$"-shaped water-conserving posture. We used a Magnetic Resonance lmaging-based 3D reconstruction method to generate 3D geometries of newt that is suitable for measuring skin surface areas, and for simulation purposes. We successfully performed 3D numerical analysis of TEWL, and proposed an original relationship to estimate TEWL rates in a large range of temperature and humidity. Finally, our results support the epidermal dysfunction hypothesis, which suggests that B. dendrobatidis compromises the ability of amphibians to rehydrate. My thesis would contribute to open new approaches to the science of amphibian water relations, and improve our knowledge of the effects of ecological changes on organisms

Triclosan and triclocarban are antimicrobials found in numerous consumer products, while caffeine is the most commonly consumed stimulant by humans. This study was undertaken to determine the effects of triclosan, triclocarban, and caffeine on the development and physiology of amphibian larvae. LC50 values of triclosan and triclocarban were determined after 96 hours for three North American larval species: Acris crepitans blanchardii, Bufo woodhousii woodhousii, Rana sphenocephala, and for a common amphibian developmental model: Xenopus laevis. Amphibian larvae were most sensitive to triclosan and triclocarban exposure during early development based upon 96-hour LC50 values. Heart rates for X. laevis and North American larvae exposed to triclosan were variable throughout development. However, significantly lower heart rates were observed in all larvae exposed to triclocarban. Metabolic rates of X. laevis and R. sphenocephala larvae exposed to triclosan were significantly affected in larvae exposed to ½ LC50 and the LC50 concentration. Metabolic rates of X. laevis larvae exposed to triclocarban were significantly affected by exposure to ½ LC50 concentrations in three of four stages investigated. No significant differences were observed in North American larvae exposed to triclocarban. Tissue uptake, lipid uptake, tissue bioconcentration factor (BCF) and lipid BCF of triclosan and triclocarban were investigated in three developmental stages of X. laevis, and in one developmental stage of B. woodhousii woodhousii, and R. sphenocephala. For most tissue and lipid uptake values, a significant increase was observed as exposure concentration increased. Tissue and lipid BCF values were dependent upon both stage and species. Chronic and acute effects of caffeine were determined in X. laevis larvae. Acute 96-hour LC50 values in four developmental stages were > 75,000 ug L-1 caffeine and heart rates were significantly different at the two earliest developmental stages. Larvae chronically exposed to caffeine reached metamorphosis at the same time as controls. Changes in chronic heart rate were dependent upon stage of development and exposure concentration. This research indicates that the toxicity of amphibian larvae exposed to triclosan, triclocarban, and caffeine appears to be dependent upon species and developmental stage, with early developmental stages being most sensitive to contaminant exposure.

Previously melittin, the α-helical basic honey bee venom peptide, was shown to inhibit F1-ATPase by binding at the β-subunit DELSEED motif of F1Fo-ATP synthase. Herein, we present the inhibitory effects of the basic α-helical amphibian antimicrobial peptides, ascaphin-8, aurein 2.2, aurein 2.3, carein 1.8, carein 1.9, citropin 1.1, dermaseptin, maculatin 1.1, maganin II, MRP, or XT-7, on purified F1 and membrane bound F1Fo Escherichia coli ATP synthase. We found that the extent of inhibition by amphibian peptides is variable. Whereas MRP-amide inhibited ATPase essentially completely (∼96% inhibition), carein 1.8 did not inhibit at all (0% inhibition). Inhibition by other peptides was partial with a range of ∼13-70%. MRP-amide was also the most potent inhibitor on molar scale (IC50 ∼3.25 μM). Presence of an amide group at the c-terminal of peptides was found to be critical in exerting potent inhibition of ATP synthase (∼20-40% additional inhibition). Inhibition was fully reversible and found to be identical in both F1Fo membrane preparations as well as in isolated purified F1. Interestingly, growth of E. coli was abrogated in the presence of ascaphin-8, aurein 2.2, aurein 2.3, citropin 1.1, dermaseptin, magainin II-amide, MRP, MRP-amide, melittin, or melittin-amide but was unaffected in the presence of carein 1.8, carein 1.9, maculatin 1.1, magainin II, or XT-7. Hence inhibition of F1-ATPase and E. coli cell growth by amphibian antimicrobial peptides suggests that their antimicrobial/anticancer properties are in part linked to their actions on ATP synthase.

In this review we discuss the inhibitory effects of dietary polyphenols and amphibian antimicrobial/antitumor peptides on ATP synthase. In the beginning general structural features highlighting catalytic and motor functions of ATP synthase will be described. Some details on the presence of ATP synthase on the surface of several animal cell types, where it is associated with multiple cellular processes making it an interesting drug target with respect to dietary polyphenols and amphibian antimicrobial peptides will also be reviewed. ATP synthase is known to have distinct polyphenol and peptide binding sites at the interface of α/β subunits. Molecular interaction of polyphenols and peptides with ATP synthase at their respective binding sites will be discussed. Binding and inhibition of other proteins or enzymes will also be covered so as to understand the therapeutic roles of both types of molecules. Lastly, the effects of polyphenols and peptides on the inhibition of Escherichia coli cell growth through their action on ATP synthase will also be presented.

Dans les zones humides, un déclin dramatique des populations d’amphibiens a été observé au niveau mondial depuis les années 80. Malgré de nombreuses études suggérant que les amphibiens sont très sensibles aux pressions anthropiques cumulées, le rôle joué par les perturbateurs endocriniens dans le déclin de leurs populations reste incertain. Parmi les perturbateurs endocriniens contaminants les zones humides, le benzo[a]pyrène (BaP) et le triclosan (TCS) sont couramment retrouvés. Au cours de ce travail, nous avons étudié la réponse physiologique de xénopes (Xenopus tropicalis) exposés à court terme (24 heures) et à long terme (du têtard à l’adulte mature) au BaP et au TCS à des concentrations réalistes d’un point de vue environnemental. En combinant une approche transcriptomique à haut débit et une caractérisation des modifications cellulaires et physiologiques, nous avons mis en évidence que le BaP, le TCS et leur mélange perturbent la physiologie globale du foie. Ce trouble est caractérisé par un phénotype semblable à de l’insulino-résistance et à une stéatopathie non alcoolique (NAFLD) associé à une hépatotoxicité médiée par une altération du métabolisme lipidique. Outre les effets directs sur le métabolisme des individus exposés, il apparaît que les perturbateurs endocriniens étudiés affectent également le succès reproducteur de ces individus et le développement de leur descendance. Prises dans leur ensemble, nos observations apportent ainsi des débuts de réponse quant aux rôles de la contamination chronique des milieux sur le déclin des populations d’amphibiens. / In wetlands, dramatic decline in amphibian populations have been described worldwide since the 80s. Despite numerous studies suggesting that amphibians are highly sensitive to cumulative anthropogenic stresses, the role played by endocrine disruptors in the decline of amphibian populations remains unclear. Among the endocrine disruptors contaminating wetlands, benzo[a]pyrene (BaP) and triclosan (TCS) are recurrently found. In this work, we studied the physiological response of Xenopus tropicalis exposed to environmentally realistic concentrations of BaP and TCS during a short-term (24 hours) and long-term (from tadpole to mature adult) period. By combining a high throughput transcriptomic approach and a characterization of cellular and physiological modifications, we showed that BaP, TCS and their mixture disrupt overall liver physiology highlighted by insulin resistance-like and non-alcoholic fatty liver disease (NAFLD)-like phenotypes together with hepatotoxicity due to the impairment of lipid metabolism. Additionally to direct metabolic impact observed on exposed individuals, the studied endocrine disruptors affected their fitness and their progeny development. Altogether, our observations bring new insights into the role plays by chronic contamination of wetlands on amphibian population decline.

No description available.