Influence of size, sex and age on venom yield of em Bothrops leucurus em (Serpentes, Viperidae) in captivity conditions

The breeding of medically important snakes is of great value, not only for the production of serums, but also for scientific studies aimed at the maintenance and well-being of animals in captivity. The present study aimed to establish the correlation between body size, sex and age in the venom production of Bothrops leucurus snakes, when manually milked under intensive captivity conditions, for one year. Were used 31 specimens kept in the Herpetology laboratory of Instituto Butantan, grouped by sex and age (young, adult and old). Biometric data (weight and length) and solid and liquid weight of venoms extracted from each fang were recorded, totaling 106 extractions in the period. We evaluated the electrophoretic profile (SDS-PAGE) under reducing conditions, the 50% lethal dose (LD50) and the minimum coagulant dose (DMC) of the extracted venoms. The body size was positively correlated with venom production in B. leucurus snakes. Regardless of sex and age, the venom showed no differences between liquid and solid composition or between right and left fang, however, the production of venom in females was twice the one found in males and more lethal. The clotting ability was lost as the animals aged, indicating that older snakes are not the best choice for venom pools in the production of antivenoms. These results are important to choose of serum production animals, and to understand the composition of snake venoms under captive conditions.

Epidemiology of accidents involving venomous animals in the State of Ceará, Brazil (2007-2019).

INTRODUCTION: Envenomation remains a neglected public health problem in most tropical countries. Epidemiological studies on accidents caused by venomous animals are scarce in the Northeast region of Brazil, mainly in the state of Ceará. The present study aimed to describe the epidemiological features of envenomation cases involving venomous animals in the State of Ceará, Northeastern Brazil, from 2007 to 2019. METHODS: The online Notifiable Diseases Information System was consulted for data on all envenomation cases involving venomous terrestrial animals. Data collected were evaluated for the number of accidents/year, number of accidents/zoological group, antivenom therapy, zone of occurrence, sex, age-group distribution, and deaths. RESULTS: A total of 54,980 cases were recorded, with the highest incidence being that of scorpion stings (67.2%), predominantly in women (52.4%; odds ratio=3.6; 95% confidence interval=3.5-3.8), equally affecting people aged 10-19 years and 40-59 years (21.4%), in the urban areas (odds ratio=10.3; 95% confidence interval=9.9-10.8), especially in the rainy months. Snakebites (16.7%) had an incidence of 8.1/100,000 inhabitants, but the highest case-fatality rates were observed in bee stings (1.3%) and spider bites (0.5%). Regarding therapeutic variables, a small percentage of people had access to serotherapy (5.3%). CONCLUSIONS: This study highlights the accidents caused by terrestrial venomous animals as a public health problem that must be monitored in Ceará. Thus, our findings suggest that preventive actions against scorpion and bee stings should be intensified during the months of higher incidence to improve public policies for patient care.

Epidemiology of accidents involving venomous animals in the State of Ceará, Brazil (2007-2019)

Abstract INTRODUCTION: Envenomation remains a neglected public health problem in most tropical countries. Epidemiological studies on accidents caused by venomous animals are scarce in the Northeast region of Brazil, mainly in the state of Ceará. The present study aimed to describe the epidemiological features of envenomation cases involving venomous animals in the State of Ceará, Northeastern Brazil, from 2007 to 2019. METHODS: The online Notifiable Diseases Information System was consulted for data on all envenomation cases involving venomous terrestrial animals. Data collected were evaluated for the number of accidents/year, number of accidents/zoological group, antivenom therapy, zone of occurrence, sex, age-group distribution, and deaths. RESULTS: A total of 54,980 cases were recorded, with the highest incidence being that of scorpion stings (67.2%), predominantly in women (52.4%; odds ratio=3.6; 95% confidence interval=3.5-3.8), equally affecting people aged 10-19 years and 40-59 years (21.4%), in the urban areas (odds ratio=10.3; 95% confidence interval=9.9-10.8), especially in the rainy months. Snakebites (16.7%) had an incidence of 8.1/100,000 inhabitants, but the highest case-fatality rates were observed in bee stings (1.3%) and spider bites (0.5%). Regarding therapeutic variables, a small percentage of people had access to serotherapy (5.3%). CONCLUSIONS This study highlights the accidents caused by terrestrial venomous animals as a public health problem that must be monitored in Ceará. Thus, our findings suggest that preventive actions against scorpion and bee stings should be intensified during the months of higher incidence to improve public policies for patient care.

Renal effects of venoms of Mexican coral snakes Micrurus browni and Micrurus laticollaris.

The Micrurus snake venoms mainly cause systemic complications, essentially neurotoxicity. Previous studies, however, have described that they are involved in the occurrence of acute kidney injury (AKI) in animal models. AKI pathogenesis in snakebites is multifactorial and involves immunological reactions, hemodynamic disturbances, and direct nephrotoxicity. The aim of this study was to compare the nephrotoxic effects of coral snake venoms from M. browni (MbV) and M. laticollaris (MlV) on the proximal tubular epithelial cell line (LLC-MK2) and isolated perfused kidney. Using an MTT assay, both venoms significantly reduced cell viability at higher concentrations (25-100 µg/mL). MlV (10 µg/mL) increased the perfusion pressure (PP) at 60, 90 and 120 min, while the MbV did it only at 90 and 120 min. Renal vascular resistance (RVR) decreased at 60 min and increased at 120 min with MbV, but decreased at 60, 90 and 120 min with MlV. Urinary flow (UF) alterations were not observed with MlV, but MbV elevated them at 90 and 120 min. Both venoms significantly decreased the glomerular filtration rate (GFR), %TNa+, %TK+ and %TCl- levels as of 60 min of perfusion. Oxidative stress analysis revealed that both venoms behaved similarly, reducing glutathione and increasing malondialdehyde levels. Kidney injury is not usually described in clinical cases of Micrurus snakebites. However, the potential for nephrotoxicity should be considered in the overall picture of envenomation.

Sexual and ontogenetic variation of Bothrops leucurus venom

Various factors, such as geographical origin, climate, sex, age and diet can influence the composition and pathophysiological activities of snake venoms. In this study, we examined the sexual and ontogenetic variations in the venom of Bothrops leucurus, a pitviper responsible for more than 80% of the snakebites in the state of Bahia, northeastern Brazilian. The venoms of 31 snakes were pooled according to sex and age (young, adult and old) and screened by SDS-PAGE (in reducing and non-reducing conditions), reverse-phase high performance liquid chromatography (RP-HPLC), gelatin zymography, and immunoblotting with therapeutic bothropic antivenom (BAV) from the Instituto Butantan. The electrophoretic and chromatographic profiles showed intraspecific ontogenetic variation, whereas sexual variations were less evident. All venoms showed gelatinolytic activity associated with 50–75 kDa protein bands. In addition, all venoms, regardless of the snakes' sex and age, cross-reacted to similar extents with BAV. Our findings show that B. leucurus venom changes during ontogenetic development and demonstrate sexual differences in its composition, indicating differences in biological activity.

Sexual and ontogenetic variation of Bothrops leucurus venom

Various factors, such as geographical origin, climate, sex, age and diet can influence the composition and pathophysiological activities of snake venoms. In this study, we examined the sexual and ontogenetic variations in the venom of Bothrops leucurus, a pitviper responsible for more than 80% of the snakebites in the state of Bahia, northeastern Brazilian. The venoms of 31 snakes were pooled according to sex and age (young, adult and old) and screened by SDS-PAGE (in reducing and non-reducing conditions), reverse-phase high performance liquid chromatography (RP-HPLC), gelatin zymography, and immunoblotting with therapeutic bothropic antivenom (BAV) from the Instituto Butantan. The electrophoretic and chromatographic profiles showed intraspecific ontogenetic variation, whereas sexual variations were less evident. All venoms showed gelatinolytic activity associated with 50–75 kDa protein bands. In addition, all venoms, regardless of the snakes' sex and age, cross-reacted to similar extents with BAV. Our findings show that B. leucurus venom changes during ontogenetic development and demonstrate sexual differences in its composition, indicating differences in biological activity.

O mosaico inflamatório nos subtipos de carcinoma basocelular / The Inflammatory Mosaic in the Histological Subtypes of Basal Cell Carcinoma / Mosaico Inflamatorio en los Subtipos de Carcinoma de Células Basales

Introdução: O carcinoma basocelular (CBC) é definido como um tumor localmente invasivo e de progressão lenta. À medida que ele se espalha, inicia-se um processo inflamatório crônico com recrutamento de diversos tipos celulares. Objetivo: Caracterizar o infiltrado inflamatório, nos diferentes subtipos de CBC, através da identificação e quantificaçãode suas células. Método: Foi realizado estudo retrospectivo de 71 blocos de parafina de pacientes diagnosticadoscom CBC não recorrente. As análises imuno-histoquímicas foram realizadas pela técnica de estreptoavidina-biotinaperoxidase (CD3, CD20, CD68, CD8, CD4, Ki-67 e MAST cell), além da técnica do azul de toluidina para mastócitos. Resultados: Os subtipos mais frequentes foram o infiltrativo (26%) e o superficial (23%). Na composição do infiltrado inflamatório, os linfócitos TCD 4+ corresponderam à população mais numerosa (216,2±22,23), seguida por mastócitos(111,0±7,88), linfócitos TCD 8+ (57,38± 5,94), linfócitos B (55,9± 6,83) e macrófagos (21,18±2,58). Houve uma baixa atividade proliferativa celular total (47,61±7,48), no entanto em formas mais agressivas esse dado foi inverso e com infiltrado rico em mastócitos. O subtipo adenoide apresentou o mais denso infiltrado, enquanto o cístico apresentouo mais discreto. Observou-se relação inversa entre o número de mastócitos e de linfócitos T, sem correlação comagressividade. Conclusão: No CBC, o infiltrado inflamatório peritumoral sugere uma resposta imunológica mediada por células TCD 4+ e composição variando de acordo com o tipo de tumor. Sugere-se que as características de cada tumor possam promover diferenças no microambiente tecidual, induzindo alterações na composição do infiltrado que poderiam tanto auxiliar quanto impedir o crescimento tumoral