BjSP, a novel serine protease from Bothrops jararaca snake venom that degrades fibrinogen without forming fibrin clots.

Snake venom serine proteases (SVSPs) are commonly described as capable of affecting hemostasis by interacting with several coagulation system components. In this study, we describe the isolation and characterization of BjSP from Bothrops jararaca snake venom, a serine protease with distinctive properties. This enzyme was isolated by three consecutive chromatographic steps and showed acidic character (pI 4.4), molecular mass of 28 kDa and N-carbohydrate content around 10%. Its partial amino acid sequence presented 100% identity to a serine protease cDNA clone previously identified from B. jararaca venom gland, but not yet isolated or characterized. BjSP was significantly inhibited by specific serine protease inhibitors and showed high stability at different pH values and temperatures. The enzyme displayed no effects on washed platelets, but was able to degrade fibrin clots in vitro and also the Aα and Bß chains of fibrinogen differently from thrombin, forming additional fibrinopeptides derived from the Bß chain, which should be related to its inability to coagulate fibrinogen solutions or platelet-poor plasma. In the mapping of catalytic subsites, the protease showed high hydrolytic specificity for tyrosine, especially in subsite S1. Additionally, its amidolytic activity on different chromogenic substrates suggests possible effects on other factors of the coagulation cascade. In conclusion, BjSP is a serine protease that acts nonspecifically on fibrinogen, generating different Bß fibrinopeptides and thus not forming fibrin clots. Its distinguished properties in comparison to most SVSPs stimulate further studies in an attempt to validate its potential as a defibrinogenating agent.

Hormonal and ultrasonographic characterization of the seasonal reproductive cycle of male and female Crotalus durissus terrificus.

Research concerning to characterize seasonal reproductive cycle in males and females of Crotalus durissus terrificus by ultrasound and hormonal measurement. Reproductive aspects (follicular and testicular cycles, and pregnancy) from 28 adult snakes (14 males and 14 females) during different months of the years were studied. Snakes housed individually in cages in an environment with controlled luminosity and humidity, and fed monthly. Females were examined by ultrasound during quiescence and active follicular phase, and pregnancy for follicular and embryo/fetal development. Males were evaluated to testicular echotexture and measurements during reproductive and non-reproductive season. The blood samples were collected from males and females for serum testosterone and progesterone determination, respectively. In 77% males the testes were identified by ultrasound and found increased size during summer, decreased serum testosterone in winter, and positive correlation between serum testosterone and testes size. There was no change in testicular echotexture in according to season. Testosterone concentration was decreased during winter and it was positively correlated with testes size. In 71% females, were observed follicular development (vitellogenesis) and gestation since winter to spring by ultrasonography. Parturition occurred mainly in summer. Pregnancy length was 123.0 ± 11.4 days, with mean 6.9 ± 1.5 newborns/female, and there was gradual increase of serum progesterone during this period. There was no variation in progesterone concentration in non-gravid females. Males and females Tropical Rattlesnake show seasonal variation of reproductive cycle and was clear a biennial cycle in female. The ultrasonography can be considered an essential tool to accomplish the follicular development, pregnancy and testicular alterations in Tropical Rattlesnake.

Strains of the Group I Lineage of Acidovorax citrulli, the Causal Agent of Bacterial Fruit Blotch of Cucurbitaceous Crops, are Predominant in Brazil.

Bacterial fruit blotch (BFB), caused by the seedborne bacterium Acidovorax citrulli, is an economically important threat to cucurbitaceous crops worldwide. Since the first report of BFB in Brazil in 1990, outbreaks have occurred sporadically on watermelon and, more frequently, on melon, resulting in significant yield losses. At present, the genetic diversity and the population structure of A. citrulli strains in Brazil remain unclear. A collection of 74 A. citrulli strains isolated from naturally infected tissues of different cucurbit hosts in Brazil between 2000 and 2014 and 18 A. citrulli reference strains from other countries were compared by pulsed-field gel electrophoresis (PFGE), multilocus sequence analysis (MLSA) of housekeeping and virulence-associated genes, and pathogenicity tests on seedlings of different cucurbit species. The Brazilian population comprised predominantly group I strains (98%), regardless of the year of isolation, geographical region, or host. Whole-genome restriction digestion and PFGE analysis revealed that three unique and previously unreported A. citrulli haplotypes (assigned as haplotypes B22, B23, and B24) occurred in Brazil. The greatest diversity of A. citrulli (four haplotypes) was found among strains collected from the northeastern region of Brazil, which accounts for more than 90% of the country's melon production. MLSA clearly distinguished A. citrulli strains into two well-supported clades, in agreement with observations based on PFGE analysis. Five Brazilian A. citrulli strains, representing different group I haplotypes, were moderately aggressive on watermelon seedlings compared with four group II strains that were highly aggressive. In contrast, no significant differences in BFB severity were observed between group I and II A. citrulli strains on melon and squash seedlings. Finally, we observed a differential effect of temperature on in vitro growth of representative group I and II A. citrulli haplotypes. Specifically, of 18 group II strains tested, all grew at 40 and 41°C, whereas only 3 of 15 group I strains (haplotypes B8[P], B3[K], and B15) grew at 40°C. Three strains representing haplotype B8(P) were the only group I strains that grew at 41°C. These results contribute to a better understanding of the genetic diversity of A. citrulli associated with BFB outbreaks in Brazil, and reinforce the efficiency of MLSA and PFGE analysis for assessing population structure. This study also provides the first evidence to suggest that temperature might be a driver in the ecological adaptation of A. citrulli populations.

Evaluation of alternative dispositives to the face-bow for mounting casts in semi-adjustable articulator / Avaliação de dispositivo alternativo ao arco facial para montagem de modelos em articulador semi ajustável

Objective. The aim of this study was to evaluate an alternative technique to face-bow for mounting casts in semi-adjustable articulators. Material and methods. Nine students from the 8th and 10th periods of the Federal University of Goias, aged over 18 years and whom presented complete natural dentition were included in the study. The four cast maxillaries of each subject were mounted in a single semi-adjustable articulator, using one of the following mounting techniques: face-bow, universal mounting jig of 0º, of 15º or universal mounting jig of 20º. On each side of the articulator three points were defined: one in the articulator (A, in the condylar region) and two in the cast (B and C). Images were obtained on each side of the articulator. Using Image J software, "the angle" "?" formed by the intersection of the line segments AB/BC was acquired. The level of significance was set at ? = 0.05. Results. Only the universal mounting jig of 15 degrees was not significantly different to the face-bow. Whereas, the universal jigs of zero and 20 degrees, showed differences to the face-bow and the 15º universal jig (p < 0.05). Conclusions. The universal mounting jig could represent an alternative to the face-bow and might encourage the use of a semi-adjustable articulator, which has been shown to be indispensable in a large number of clinical situations.

Objetivo. O objetivo deste estudo foi avaliar uma técnica alternativa ao arco facial para montagem de modelos em articuladores semi-ajustáveis. Material e métodos. Nove estudantes do 8º e 10º períodos da Faculdade de Odontologia da Universidade Federal de Goiás, com mais de 18 anos e que apresentou dentição natural completa foram incluídos no estudo. Quatro modelos do arco superior de cada sujeito foram montados em um único articulador semi-ajustável, usando uma das seguintes técnicas de montagem: arco facial, plano de camper de 0º, 15º ou 20º. Em cada lado do articulador foram definidos três pontos: um no articulador (A, na região do côndilo) e dois no moldelo (B e C). As imagens foram obtidas em cada um dos lados do articulador. Usando o software Image J, o "?" ângulo formado pela intersecção dos segmentos de linha AB / BC foi adquirido. O nível de significância foi estabelecido em ? = 0,05. Resultados. Apenas o plano de camper de 15º, não foi significativamente diferente do arco facial. Enquanto que, os plano de camper de zero e 20º, mostraram diferenças para o arco facial e o plano de 15º (p <0,05). Conclusões. O plano de camper pode representar uma alternativa para o arco facial e pode encorajar o uso de um articulador semi-ajustável, o qual tem sido mostrado ser indispensável num grande número de situações clínicas.

Serological investigation and PCR in detection of pathogenic leptospires in snakes / Investigação sorológica e PCR na detecção de leptospiras patogênicas em serpentes

Detection of Leptospira by PCR had not yet been described in snakes. This study investigated, by microscopic agglutination test (MAT) and PCR, the presence of antibodies to Leptospira spp. and Leptospira spp., respectively, in venomous and non-venomous wildlife and captivity snakes. All snakes were divided into three groups to be compared: Group 1 (wildlife snakes - WS); Group 2 (snakes in intensive captivity - IC), and Group 3 (collective semi-extensive captivity -CC). Of the 147 snakes studied, 52 (35.4 percent) were positive for leptospirosis by MAT, 8 (15.4 percent) belonging to Group 1 (WS), 34 (65.4 percent) to Group 2 (IC) and 10 (19.2 percent) to Group 3 (CC). Jararaca (Bothrops jararaca) presented the highest average titer (66.7 percent, N=22/33) among the three group studied, and Hardjo prajtino was the most prevalent serovar (88.5 percent, N=46/52), with titers varying from 100 to 3200. Leptospira interrogans was revealed by PCR in kidney and liver of caiçaca (Bothrops moojeni) and jararaca-pintada (Bothrops pauloensis), showing 100 percent and 93 percent identity respectively. Future studies should be carried out for better understanding of the role of snakes as a reservoir of Leptospira in nature.

A detecção de Leptospira pela técnica de PCR não havia sido descrita em serpentes. Este estudo investigou pelo teste de aglutinação microscópica (MAT) e PCR, a presença de anticorpos anti-Leptospira spp. e Leptospira spp., respectivamente, em serpentes peçonhentas e não peçonhentas de vida livre e de cativeiro. As serpentes foram divididas em três grupos para comparação: Grupo 1 (serpentes recém-chegadas da natureza - WS); Grupo 2 (serpentes em regime de cativeiro intensivo -IC) e Grupo 3 (serpentes em regime de cativeiro coletivo semi-extensivo - CC). Do total de 147 serpentes estudadas, 52 (35,4 por cento) foram positivas para leptospirose pelo MAT, as quais 8 (15,4 por cento) pertenciam ao Grupo 1 (WS), 34 (65,4 por cento) ao Grupo 2 (IC) e 10 (19,2 por cento) ao Grupo 3 (CC). Das espécies estudadas, a jararaca (Bothrops jararaca) apresentou maior soropositividade (66,7 por cento, N=22/33). O sorovar mais prevalente foi o Hardjo prajtino (88,5 por cento, N=46/52) e os títulos variaram de 100 a 3200. Leptospira interrogans foi revelada por PCR nos rins e no fígado de caiçaca (Bothrops moojeni) e de jararaca-pintada (Bothrops pauloensis), mostrando 100 por cento e 93 por cento de identidade, respectivamente. Futuros estudos devem ser realizados para melhor compreensão do papel das serpentes como reservatório de leptospiras na natureza.

Africanized honey bee (Apis mellifera) venom profiling: Seasonal variation of melittin and phospholipase A(2) levels.

Apis mellifera venom is comprised basically of melittin, phospholipase A(2), histamine, hyaluronidase, catecholamine and serotonin. Some of these components have been associated with allergic reactions, amongst several other symptoms. On the other hand, bee mass stinging, caused by Africanized honey bee (AHB), is increasingly becoming a serious public health issue in Brazil; therefore, the development of efficient serum-therapies has become necessary. In this work, we have analyzed the venom composition of AHB in Brazil through one year. In order to verify the homogeneity of this venom, one specific hive was selected and the correlation with climatic parameters was assessed. It was possible to perceive a seasonal variation on the venom contents of melittin and phospholipase A(2). Moreover, both compounds presented a synchronized variation of their levels, with an increased production in the same months. This variation does not correlate or synchronize with any climatic parameter. Data on the variation of the AHB venom composition is necessary to guide future intra and inter species studies.

Africanized honey bee (Apis mellifera) venom profiling: Seasonal variation of melittin and phospholipase A2 levels

AbstractApis mellifera venom is comprised basically of melittin, phospholipase A2, histamine, hyaluronidase, catecholamine and serotonin. Some of these components have been associated with allergic reactions, amongst several other symptoms. On the other hand, bee mass stinging, caused by Africanized honey bee (AHB), is increasingly becoming a serious public health issue in Brazil; therefore, the development of efficient serum-therapies has become necessary. In this work, we have analyzed the venom composition of AHB in Brazil through one year. In order to verify the homogeneity of this venom, one specific hive was selected and the correlation with climatic parameters was assessed. It was possible to perceive a seasonal variation on the venom contents of melittin and phospholipase A2. Moreover, both compounds presented a synchronized variation of their levels, with an increased production in the same months. This variation does not correlate or synchronize with any climatic parameter. Data on the variation of the AHB venom composition is necessary to guide future intra and inter species studies.

Comparison of wildlife and captivity rattlesnakes (Crotalus durissus terrificus) microbiota / Comparação da microbiota de cascavéis (Crotalus durissus terrificus) de vida-livre e cativeiro

The study evaluated and compared the aerobic microbiota from the oral cavity, cloaca and venom of Crotalus durissus terrificus snakes, recently caught from the wild and kept under quarantine (WQ), individual captivity (IC) and collective captivity (CC). Antimicrobial drug effectiveness on isolated agents also was assayed. From group I, II and III were isolated, respectively, 29 (63.04 percent), 38 (90.48 percent) and 21 (42.86 percent) microorganisms from the cloaca; 15 (32.61 percent), 3 (7.14 percent) and 25 (51.02 percent) microorganisms from the oral cavity; and, 2 (4.35 percent), 1 (2.38 percent) and 3 (6.12 percent) microorganisms from venom. The most frequent bacteria were Pseudomonas aeruginosa, Proteus vulgaris and Morganella morganii, with sensitivity to amikacin, gentamicin, norfloxacin, sulfazotrin and tobramycin. Snakes kept in semi-open captivity exhibited the fewest microorganisms in oral cavities, perhaps due to the environment in captivity, with different temperature gradients, running water, absence of daily handling, circulating air, possibility of moving around, daily cleaning, and sunlight access.

Este estudo avaliou e comparou a microflora aeróbica da cavidade oral, cloaca e veneno de serpentes Crotalus durissus terrificus recém-capturadas da natureza e mantidas sob quarentena (WQ), mantidas em cativeiro coletivo (CC) e em cativeiro individual (IC). A eficácia de drogas antimicrobianas de agentes isolados foi também avaliada. Foram isolados microorganismos dos grupos I, II e III respectivamente: 29 (63.04 por cento), 38 (90.48 por cento) e 21 (42.86 por cento) da cloaca; 15 (32.61 por cento), 3 (7.14 por cento) e 25 (51.02 por cento) da cavidade oral, e finalmente 2 (4.35 por cento), 1 (2.38 por cento) e 3 (6.12 por cento) do veneno. As bactérias mais frequentes foram Pseudomonas aeruginosa, Proteus vulgaris e Morganella morganii, com sensibilidade para amikacina, gentamicina, norfloxacina, sulfazotrina e tobramicina. Serpentes mantidas no cativeiro semi-aberto mostraram menor número de agentes infecciosos em cavidade oral, talvez devido ao ambiente de cativeiro com diferentes gradientes de temperatura, água corrente, ausência de manejo diário, ampla circulação de ar, possibilidade de movimentação pelos animais, limpeza diária e acesso ao Sol.