Estudos estruturais por difração de raios X de fosfolipases A2 em presença de íons com importância funcional

Snakes from Bothrops genus are responsible for more than 90% of the ophidian accidents in Brazil. One of the main complications from this kind of accident is muscular necrosis, which is related to the action of phospholipases A2 and metalloproteases, two groups of enzymes found in the venom of these animals. Although this complication cannot be solved by serum therapy administration, a great number of studies have been performed with the attempt to know the pharmacological sites of these toxins aiming, in the future, the development of complementary treatments to serum therapy. This work proposes structural studies of bothropic phospholipases A2 (PLA2s) in the presence of ions relevant to their activity, using the X-ray crystallography technique. Recently, it was demonstrated ions, as manganese, calcium and others, interfere in the biological activity of the PLA2s. Particularly, Lys49-PLA2s in the presence of manganese ions have miotoxicity reduced. Asp49-PLA2s show catalytic activity dependent of calcium, although structural studies with a miotoxic Asp49-PLA2, BthTX-II, suggest a possible catalytic mechanism independent of calcium. Therefore, co-crystallization of BthTX-II in the presence of calcium ions and of PrTX-I in the presence of manganese ions were performed. Comparative structural studies among obtained results and others already published in the literature were performed aiming a better understanding of the structure-function relationship of these toxins. The BthTX-II with the presence of calcium do not show this ion in the loop of coordination of calcium, presence necessary to develop the catalyses. After comparison of this model with the native one, only one distortion was found, but no apparent relationship with the residues responsible for its activity. In the PrTX-I structure, regions candidates of manganese ions were also found... (Complete abstract click electronic access below)

Levantamento das espécies de serpentes de Botucatu

Throughout the analysis of the collections JJ, CEVAP, IBSP, ZUEC and UEL, a study on the ophiofauna of Botucatu was made. We present a preliminary list of the species of snakes here found, with small comments on their natural history. The number of specimens studied was 943. We registered, for Botucatu, 51 species of snakes, distributed in 31 genera and 6 families. The families here found were Anomalepididae (1 spp.), Boidae (1 spp.), Colubridae (7 spp.), Dipsadidae (32 spp.), Elapidae (3 spp.) and Viperidae (7 spp.). The analysis of the relative abundance shows that Dipsadidae was the most abundant family, with n=425 (44,83%), followed by Viperidae, with n=388 (40,93%), Boidae, n=62 (6,54%), Colubridae, n=57 (6,01%), Elapidae, n=15 (1,6%) and, at last, Anomalepididae, with n=1 (0,1%). The five more representative species were Crotalus durissus (n=135, 14,31%), Oxyrhopus guibei (n=123, 12,8%) Bothropoides jararaca (N=121, 12,6%), Bothropoides neuwiedi (N=95, 9,88%) and Sibynomorphus mikani (N=65, 6,76%). A higher number of individuals collected was registered for the months of january to april that, together, sum up to almost 50% of the total. The months of june to september registered a lower number of individuals. The spacial distribution analysis shows that a higher number of snakes was found on the country areas of Botucatu (n=270, 41,54%), specially on pastures. Due to the lack of studies of Botucatu’s ophiofauna, this list is probably underestimated. It is mandatory that future studies approaching this group and its ecological components on this region are made, using appropriate sampling methodologies, in order to form an accurate list of the species of snakes of Botucatu

Efeito da interação entre Bothropstoxina-I e Crotapotina na junção neuromuscular de camundongos “in vitro”: estágio em iniciação científica

A bothropstoxina-I (BthTX-I) é uma fosfolipase A2 (PLA2) Lys49 miotóxica isolada do veneno da Bothrops jararacussu. Embora seja desprovida de atividade neurotóxica in vivo, esta toxina bloqueia a transmissão neuromuscular in vitro. A relação entre as atividades miotóxica e paralisante da BthTX-I ainda não está esclarecida. A crotapotina corresponde à subunidade não-enzimática da crotoxina, principal fração tóxica do veneno da Crotalus durissus terrificus. Isoladamente a crotapotina é atóxica, porém atua como carreadora da PLA2 Asp49 da crotoxina, potencializando sua ação neurotóxica. Esta proteína também é capaz de se complexar com outras PLA2s (Asp49 ou Lys49) de venenos ofídicos, alterando suas toxicidades. Neste trabalho avaliamos a influência da crotapotina sobre o bloqueio neuromuscular e a atividade miotóxica da BthTX-I in vitro. Preparações do nervo frênico-músculo diafragma de camundongos machos foram montadas em cubas para o registro das contrações musculares evocadas direta e indiretamente. Cortes transversais do músculo foram submetidos à coloração por hematoxilina e eosina para a avaliação do padrão morfológico. A BthTX-I (1 μM) isoladamente, ou pré-incubada com crotapotina (2 M) à 35 ºC por 30 minutos, foram adicionadas às preparações. A análise dos dados foi realizada por testes não paramétricos (p<0.05). A BthTX-I induziu bloqueio irreversível e tempo-dependente das contrações musculares diretas e indiretas. O tempo para o bloqueio de 50% das contrações indiretas (18,98 ± 1,94 min, n=4) foi significativamente menor que o das diretas (45,97 ± 5,61 min, n=5). A pré-incubação com a crotapotina não alterou de forma significativa o bloqueio das contrações diretas ou indiretas induzidos pela BthTX-I. Isoladamente, a crotapotina não afetou as contrações... (Resumo completo, clicar acesso eletrônico abaixo)

Critérios técnicos e de participação social para a recuperação florestal: quais as diferenças na definição de áreas prioritárias?

The Jararaca River Basin suffers significative environmental impacts caused by inaccurate land use. In Brazil, the areas for permanent preservation are defined and protected by the 2012 Federal Law 12.651. These areas are located in the bank side and other specific places. The objective of this paper was to analyze the results of possible alternatives in function of different procedures used in the proposal elaboration. The methodology used was the elaboration of a priority map for the recovery of these areas using the Geographic Information System with multicriterial analyses and comparing it with the guidelines from the Jararaca River Basin Management Plan. As a result, there were identified differences in the priorities defined by technical issues from the priorities defined by public consultation process.

Bothropoides pauloensis venom effects on isolated perfused kidney and cultured renal tubular epithelial cells

Coordenadação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Production, characterization and structural analysis of proteins from Corynebacterium pseudotuberculosis and snake venoms

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Caracterização por espectrometria de massas e investigação das atividades anti-inflamatória e gastroprotetora do extrato etanólico e diterpenos clerodânicos de folhas de Casearia sylvestris Swartz

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)