Hiding in the lianas of the tree of life: Molecular phylogenetics and species delimitation reveal considerable cryptic diversity of New World Vine Snakes.

The Brown Vine Snake, Oxybelis aeneus, is considered a single species despite the fact its distribution covers an estimated 10% of the Earth's land surface, inhabiting a variety of ecosystems throughout North, Central, and South America and is distributed across numerous biogeographic barriers. Here we assemble a multilocus molecular dataset (i.e. cyt b, ND4, cmos, PRLR) derived from Middle American populations to examine for the first time the evolutionary history of Oxybelis and test for evidence of cryptic lineages using Bayesian and maximum likelihood criteria. Our divergence time estimates suggest that Oxybelis diverged from its sister genus, Leptophis, approximately 20.5 million years ago (Ma) during the lower-Miocene. Additionally, our phylogenetic and species delimitation results suggest O. aeneus is likely a complex of species showing relatively deep species-level divergences initiated during the Pliocene. Finally, ancestral area reconstructions suggest a Central American origin and subsequent expansion into North and South America.

Induction of systemic inflammation and thickening of subepicardiac arteries in an animal model of uremia.

UNLABELLED: Although renal dysfunction is a known risk factor for cardiovascular disease (CVD), there are few experimental studies investigating the cardiovascular consequences of this condition. OBJECTIVE: To analyze the impact of the induction of renal dysfunction on biomarkers of cardiovascular risk and on the histology of subepicardial vessels. METHODS: This experimental study involved thirty Wistar male rats, which were divided into two groups. One (chronic kidney disease - CKD group) underwent renal ablation, and the other (SHAM group) was submitted to kidney manipulation only. Both groups were followed up for eight weeks. During follow-up, serum levels of urea, phosphorus and TNF-α were measured. Heart tissue was processed for histological analysis. RESULTS: The CKD group had increased levels of urea and phosphorus, in comparison with the SHAM group. The levels of TNF-α were increased in the CKD group and undetectable in the SHAM group (p < 0.05). Thickness of the middle layer of the subepicardial vessels of the CKD group was significantly higher than that of the SHAM group (p = 0.011). CONCLUSION: Induction of renal dysfunction in rats increased the biomarkers of cardiovascular risk and led to a thickening of the subepicardial vessels when compared with normal controls.

Indução de resposta inflamatória sistêmica e espessamento de artérias subepicárdicas em um modelo animal de uremia / Induction of systemic inflammation and thickening of subepicardiac arteries in an animal model of uremia

A disfunção renal é um fator de risco para doença cardiovascular (DCV). Estudos experimentais controlados que possam analisar o impacto da disfunção renal no sistema cardiovascular, isolando esses fatores relacionados à uremia dos fatores de risco tradicionais, que são altamente prevalentes na população com doença renal crônica (DRC), ainda são escassos. OBJETIVO: Analisar o impacto cardiovascular em ratos com disfunção renal, analisando biomarcadores de risco cardiovascular e a histologia das artérias subepicárdicas desses animais. MÉTODOS: Estudo experimental envolvendo trinta ratos machos Wistar, divididos em dois grupos. Um grupo foi submetido à ablação renal e o outro grupo SHAM (grupo controle) à manipulação do pedículo renal. Ambos os grupos foram acompanhados por oito semanas, período em que foram feitas dosagens de ureia, fósforo e do fator de necrose tumoral alfa (TNF-α). Lâminas obtidas de cortes do miocárdio foram confeccionadas para análise das características das arteríolas subepicárdicas. RESULTADOS: O grupo DRC apresentou níveis elevados de uréia e fósforo em relação ao grupo SHAM. Já os níveis de TNF-α, em todas as análises, foram indetectáveis nos animais do grupo SHAM, em contraste com o grupo DRC, onde se observaram elevados níveis de TNF-α (p < 0,05). A espessura da camada média dos vasos subepicárdicos do grupo DRC foi significativamente maior do que em relação ao grupo SHAM (p = 0,011). CONCLUSÃO: A indução de disfunção renal determinou alterações em biomarcadores de risco cardiovascular e um aumento na espessura dos vasos subepicárdicos estudados em comparação aos animais com função renal normal.

Although renal dysfunction is a known risk factor for cardiovascular disease (CVD), there are few experimental studies investigating the cardiovascular consequences of this condition. OBJECTIVE: To analyze the impact of the induction of renal dysfunction on biomarkers of cardiovascular risk and on the histology of subepicardial vessels. METHODS: This experimental study involved thirty Wistar male rats, which were divided into two groups. One (chronic kidney disease - CKD group) underwent renal ablation, and the other (SHAM group) was submitted to kidney manipulation only. Both groups were followed up for eight weeks. During follow-up, serum levels of urea, phosphorus and TNF-α were measured. Heart tissue was processed for histological analysis. RESULTS: The CKD group had increased levels of urea and phosphorus, in comparison with the SHAM group. The levels of TNF-α were increased in the CKD group and undetectable in the SHAM group (p < 0.05). Thickness of the middle layer of the subepicardial vessels of the CKD group was significantly higher than that of the SHAM group (p = 0.011). CONCLUSION: Induction of renal dysfunction in rats increased the biomarkers of cardiovascular risk and led to a thickening of the subepicardial vessels when compared with normal controls,.