Geographical genetics of Pseudoplatystoma punctifer (Castelnau, 1855) (Siluriformes, Pimelodidae) in the Amazon Basin.

Geographical genetics allows the evaluation of evolutionary processes underlying genetic variation within and among local populations and forms the basis for establishing more effective strategies for biodiversity conservation at the population level. In this study, we used explicit spatial analyses to investigate molecular genetic variation (estimated using 7 microsatellite markers) of Pseudoplatystoma punctifer, by using samples obtained from 15 localities along the Madeira River and Solimões, Amazon Basin. A high genetic diversity was observed associated with a relatively low FST (0.057; P < 0.001), but pairwise FST values ranged from zero up to 0.21 when some pairs of populations were compared. These FST values have a relatively low correlation with geographic distances (r = 0.343; P = 0.074 by Mantel test), but a Mantel correlogram revealed that close populations (up to 80 km) tended to be more similar than expected by chance (r = 0.360; P = 0.015). The correlogram also showed a exponential-like decrease of genetic similarity with distance, with a patch-size of around 200 km, compatible with isolation-by-distance and analogous processes related to local constraints of dispersal and spatially structured levels of gene flow. The pattern revealed herein has important implications for establishing strategies to maintain genetic diversity in the species, especially considering the threats due to human impacts caused by building large dams in this river system.

Heterologous amplification and characterization of microsatellite markers in the Neotropical fish Leporinus friderici.

Leporinus friderici, native to the Amazon Basin and popularly known as "piau-três-pintas", has great ecological and economic importance; it is widely fished and consumed throughout much of tropical South America. Knowledge of the genetic diversity of this native species is important to support management and conservation programs. We evaluated microsatellite loci amplification, using heterologous primers, in 31 individuals of L. friderici. These samples were collected from natural populations of the Araguaia River basin, in central Brazil, and the DNA was extracted from samples of muscle tissue. Eight loci were successfully analyzed. Six of them were polymorphic, and the number of alleles ranged from three to 10. Values of expected heterozygosities for these polymorphic loci ranged from 0.488 to 0.795. Exclusion probability (0.983), the identity probability (0.000073), and the mean genetic diversity values were high, showing that these microsatellite markers are suitable for assessing the genetic variability of L. friderici populations. There is a growing interest in studies that evaluate the genetic variability of natural populations for various purposes, such as conservation. Here, we showed that a viable alternative to the costly development of specific primers for fish populations is simply testing for heterologous amplification of microsatellite markers available from research on other species.

Development of microsatellite markers for Hoplias malabaricus (Erythrinidae).

We identified 14 microsatellite loci for the wolf fish, Hoplias malabaricus (Erythrinidae), from a genomic shotgun library. Twenty-five primers were designed, and 48 individuals of H. malabaricus from four localities of northwest Goiás, in central Brazil, were genotyped to characterize the polymorphism at each locus. Fourteen primers amplified clearly interpretable products using a single PCR protocol; six loci were polymorphic, but with a low number of alleles per locus (2 or 3). Expected heterozygosities for polymorphic loci ranged from 0.136 to 0.505. Combined paternity exclusion probability (0.638) was low and combined genetic identity (0.056) was high in studies of parentage. The low polymorphism may be due to the small microsatellite size and the large size of the motifs.

Isolation and characterization of microsatellite markers in the armored catfish Hypostomus gymnorhynchus (Loricariidae).

We isolated and characterized 10 microsatellite loci in the armored catfish (Hypostomus gymnorhynchus, Loricariidae), using a genomic shotgun library to obtain the repetitive sequences. Twenty-four primers were designed and 14 individuals of H. gymnorhynchus from the Caiapó River, in central Brazil, were genotyped using these primers to analyze the polymorphism at each locus. All loci showed low polymorphism, with a low number of alleles per locus (1 or 2), except locus Hg_E19, which had 11 alleles. Expected heterozygosities for polymorphic loci ranged from 0.182 to 0.901. Combined paternity exclusion probability (0.857) was low and combined genetic identity (0.0026) was high, when we examined parentage. The low degree of polymorphism that we detected may be due to the small sample size and the small microsatellite size, despite the large motif size.

Genetic diversity in populations of the viper Bothrops moojeni Hoge, 1966 in Central Brazil using RAPD markers.

Bothrops moojeni is an abundant venomous snake responsible for most of the snakebite cases in the Central region of Brazil and as a result of the anthropogenic habitat disturbance, such as the increase in extensive farming, the range of B. moojeni has been greatly fragmented. Here, we obtained genomic DNA from a total of 75 snakes belonging to four populations. Genetic variability evaluated for five RAPD primers was low (He = 0.20) and was not spatially structured. We found evidence of significant genetic divergence among B. moojeni populations that were isolated (PhiST values of 0.21 and 0.25), while populations more proximal exhibited less divergence (PhiST values of 0.04 and 0.08). We found only moderate divergence (PhiST value of 0.12) between two populations greatly isolated (851.83 km apart) along with great differentiation (0.24) between two proximal populations (290 km apart). Even though these populations are close to each other, they occur in an urbanized area that is almost completely covered by extensive crops, representing an obstruction to the mobility of this viper. Molecular variance analysis (AMOVA) showed some degree of subdivision in these populations, with a PhiST value of 0.16, significant to the level of 1% by 1000 random permutations. We also performed a Bayesian analysis that confirmed the AMOVA results and found a value of thetaB = 0.14 and an f = 0.27, suggesting a high level of endogamy. This is the first study that characterizes genetic variability for this important species of the Bothrops genus, and our data are of significant importance in terms of classifying populations in relation to their conservational value and management strategies. Thus, given the high levels of population structure found in this case, we recommend sampling as many populations as possible to maximize the genetic variability to be preserved when aiming for in situ conservation. The same should be done to perform samplings toward ex situ conservation.

Protein from Hevea brasiliensis "Hev b 13" latex attenuates systemic inflammatory response and lung lesions in rats with sepsis.

Sepsis induces a severe systemic inflammatory response that may result in multiple organ dysfunction and death. Studies using a protein derived from natural Hevea brasiliensis (rubber tree) latex, denominated Hev b 13, have demonstrated important anti-inflammatory effects, but no data have been published regarding its effects on sepsis. The aim of this study was to investigate the effects of Hev b 13 on the inflammatory response and lung lesions of septal rats. Male Wistar rats were submitted to cecal ligation and puncture (CLP), randomized into groups and treated with subcutaneously administered doses of 0.5/2.0/3.0 mg/Kg of Hev b 13. Next, animals were subdivided into three different points in time (1, 6 and 24 hours after treatments) for collection of blood samples and euthanasia accompanied by organ removal. Total and differential leukocyte counts, cytokine dosage and histological assessment were analyzed. Treatment with Hev b 13 resulted in a significant decline in total and differential leukocytes as well as suppression of TNF-α and IL-6 production, associated with the increase in IL-10 and IL-4 in plasma and lung tissue. Moreover, it reduced morphological and pathological changes found in the lungs, including neutrophil infiltration, edema and alveolar thickening. The present study concluded that Hev b 13 exerts anti-inflammatory effects and attenuates lung lesions in septal rats, showing potential for clinical application.

Angiogenic activity of latex from Euphorbia tirucalli Linnaeus 1753 (Plantae, Euphorbiaceae).

To assess the pro-angiogenic activity of Euphorbia tirucalli, commonly known as "avelós" plant, we performed a series of tests by applying an aqueous E. tirucalli latex solution (10 mg/mL) to the chorioallantoic membranes (CAMs) of 80 fertilized chicken eggs incubated in a temperature- and humidity-controlled automatic incubator. The results indicated that the aqueous latex solution increased vascular network formation compared to that with the negative control (p < 0.05) and the inhibitor control (p < 0.05). This suggests that under the experimental conditions tested, the aqueous latex solution induced an inflammatory response leading to neoangiogenesis.

Human envenomation by the South American opisthoglyph Clelia clelia plumbea (Wied).

A 4-year-old girl was hospitalized 10 hr after having been envenomated by a 1.4 m Clelia clelia plumbea, a colubrid. Although the patient exhibited pronounced edema and local hemorrhage, she did not manifest systemic symptoms. Because the attending physician viewed the case as a possible Bothrops bite, anti-Bothrops antivenom (FUNED) was administered. All local symptoms disappeared gradually over a period of 3 days.

Experimental myonecrosis induced by the venoms of South American Micrurus (coral snakes).

Venoms from 11 taxa of Micrurus (coral snakes) from Brazil and Colombia were tested for myotoxic activity in mice. All venoms, except that of M. surinamensis, induced myotoxicity as judged by the increase in plasma creatine kinase levels and by histological analysis. Qualitatively, these venoms induced a similar necrotic pattern, although there were conspicuous quantitative differences between them.

Toxins isolated from the venom of the Brazilian coral snake (Micrurus frontalis frontalis) include hemorrhagic type phospholipases A2 and postsynaptic neurotoxins.

Toxins isolated from the venom of the Brazilian coral snake (Micrurus frontalis frontalis) include hemorrhagic type phospholipases A2 and postsynaptic neurotoxins. Toxicon 35, 1193-1203, 1997.-Two sets of proteins have been purified from the venom of the Brazilian coral snake, Micrurus frontalis frontalis. One set has mol. wts, as shown by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), in the 8000-13,000 range and includes some proteins which are toxic to mice and others which are not. These proteins appear to be isoforms of postsynaptic toxins. The other set shows phospholipase A2 (PLA2) activity and the toxic members of this set promote hemorrhage in mice in a manner closely resembling that produced by PLA2s isolated from the venom of the Australian tiger snake (Notechis scutatus scutatus). These PLA2s migrate on SDS-PAGE with apparent mol. wts in the 18,000-22,000 range which is characteristic of PLA2s that have an alpha-helix D similar to pancreatic PLA2s. Elapid venom PLA2s of the type which typically migrate on SDS-PAGE with mol. wts in the 13,000-16,000 range and do not have alpha-helix D have not been detected in M. f. frontalis venom.

Protein from Hevea brasiliensis "Hev b 13" latex attenuates systemic inflammatory response and lung lesions in rats with sepsis / Proteína do latex de Hevea brasiliensis "Hev b 13" atenua resposta inflamatória sistêmica e lesão pulmonar de ratos com sepse

Abstract Sepsis induces a severe systemic inflammatory response that may result in multiple organ dysfunction and death. Studies using a protein derived from natural Hevea brasiliensis (rubber tree) latex, denominated Hev b 13, have demonstrated important anti-inflammatory effects, but no data have been published regarding its effects on sepsis. The aim of this study was to investigate the effects of Hev b 13 on the inflammatory response and lung lesions of septal rats. Male Wistar rats were submitted to cecal ligation and puncture (CLP), randomized into groups and treated with subcutaneously administered doses of 0.5/2.0/3.0 mg/Kg of Hev b 13. Next, animals were subdivided into three different points in time (1, 6 and 24 hours after treatments) for collection of blood samples and euthanasia accompanied by organ removal. Total and differential leukocyte counts, cytokine dosage and histological assessment were analyzed. Treatment with Hev b 13 resulted in a significant decline in total and differential leukocytes as well as suppression of TNF-α and IL-6 production, associated with the increase in IL-10 and IL-4 in plasma and lung tissue. Moreover, it reduced morphological and pathological changes found in the lungs, including neutrophil infiltration, edema and alveolar thickening. The present study concluded that Hev b 13 exerts anti-inflammatory effects and attenuates lung lesions in septal rats, showing potential for clinical application.

Resumo Sepse induz uma resposta inflamatória sistêmica grave podendo resultar em disfunção de múltiplos órgãos e morte. Pesquisas utilizando uma proteína derivada do látex natural de Hevea brasiliensis (seringueira), denominada Hev b 13 tem demonstrado importantes efeitos anti-inflamatórios, mas nenhum dado foi publicado dos seus efeitos na sepse. O objetivo deste estudo foi investigar os efeitos da Hev b 13 na resposta inflamatória e na lesão pulmonar de ratos com sepse. Ratos machos da linhagem Wistar foram submetidos a ligação e perfuração do ceco (LPC), randomizados em grupos e tratados com as doses 0,5/2,0/3,0 mg/Kg de Hev b 13 subcutâneo. Após subdividiu-se os animais em três pontos diferentes de tempo (1, 6 e 24 horas após os tratamentos) para coleta de amostras sanguíneas e eutanásia com remoção dos órgãos. Contagem total e diferencial de leucócitos, dosagem de citocinas e avaliação histológica foram analisadas. O tratamento com a Hev b 13 resultou em diminuição significativa de leucócitos totais e diferenciais bem como suprimiu a produção de TNF-α e IL-6, associado ao aumento de IL-10 e IL-4 no plasma e tecido pulmonar. Além disso, reduziu as alterações morfológicas e patológicas encontradas nos pulmões, incluindo infiltrado de neutrófilos, edema e espessamento alveolar. Este estudo concluiu que a Hev b 13 tem efeitos anti-inflamatórios e atenua lesões pulmonares em ratos com sepse, apresentando potencialidades para aplicabilidade clínica.

Geographical patterns and partition of turnover and richness components of beta-diversity in faunas from Tocantins river valley.

There has been a resurging interest in patterns of ß-diversity, especially by the mechanisms driving broad-scale, continental and global patterns, and how partitioning ß-diversity into richness (or nestedness) and turnover components can be linked with such mechanisms. Here we compared two recent methodologies to find richness and turnover components of ß-diversity, using a large regional scale dataset of mammal, bird, reptiles and amphibian species found in seven regions of Central, North and Northeastern Brazil. As well as a simple comparison of the metrics available, we analyzed spatial patterns (i.e., distance-decay similarity) and the effects of biome type in these components using raw and partial Mantel tests. Our analyses revealed that turnover estimated using Baselga's (2010) approach is slightly higher than the estimate using Carvalho's et al. (2012) approach, but all analyses show consistent spatial patterns in species turnover using both methods. Spatial patterns in ß-diversity revealed by Mantel tests are also consistent with expectations based on differential dispersal abilities. Our results also reinforce that spatial patterns in ß-diversity, mainly in the turnover components expressing faunal differentiation, are determined by a mix or broad scale environmental effects and short distance spatially-structured dispersal.

Comparative chromatography of Brazilian coral snake (Micrurus) venoms.

1. Elution profiles of 11 coral snake venoms, including those of Micrurus albicinctus, M. corallinus, M. frontalis altirostris, M. f. brasiliensis, M. f. frontalis, M. fulvius fulvius, M. ibiboboca, M. lemniscatus ssp., M. rondonianus, M. spixii spixii and M. surinamensis surinamensis, were compared using high performance gel filtration and reverse phase media. 2. Micrurus venom profiles were compared with those of "outgroup" taxa Bothrops moojeni, Naja naja kaouthia and Bungarus multicinctus. 3. Purified elapid venom constituents were also chromatographed under identical conditions in order to suggest possible identities of Micrurus venom constituents. 4. Masses of various components were confirmed by mass spectrometry. 5. Phospholipase constituents in three venoms were positively identified based on their reverse phase chromatograms. 6. Venoms of M. rondonianus and M. s. surinamensis are shown to be significantly different in their peptide composition from other Micrurus venoms.