Search results for "snake"
showing 10 items of 41 documents
Species- and Subtype-Specific Recognition by Antibody WF6 of a Sequence Segment Forming an α-Bungarotoxin Binding Site on the Nicotinic Acetylcholine…
1992
The monoclonal antibody WF6 competes with acetylcholine and alpha-bungarotoxin (alpha-BGT) for binding to the Torpedo nicotinic acetylcholine receptor (nAChR) alpha 1 subunit. Using synthetic peptides corresponding to the complete Torpedo nAChR alpha 1 subunit, we previously mapped a continuous epitope recognized by WF6, and the prototope for alpha-BGT, to the sequence segment alpha 1(181-200). Single amino acid substitution analogs have been used as an initial approach to determine the critical amino acids for WF6 and alpha-BGT binding. In the present study, we continue our analysis of the structural features of the WF6 epitope by comparing its cross-reactivity with synthetic peptides corr…
El «apareamiento oral» (oris coitus) de las serpientes y su simbología en la literatura emblemática neolatina
2009
Este artículo trata del denominado «apareamiento por la boca» (oriscoitus) de las serpientes y su simbología en los libros de emblemas latinos de los siglos XVI y XVII, revisando las diferentes interpretaciones que los autores ofrecen de este ancestral argumento e identificando las fuentes (literarias y gráficas) clásicas, medievales y renacentistas. Asimismo, se establecen las curiosas imbricaciones que presenta tal metáfora con arquetipos míticos. This paper is about the so called «oral mating» (oris coitus) of the serpents and its symbolism in the books of Latin emblems of the XVIth and XVIIth century, revising the different interpretations that the authors offer of this ancient argument…
Il tarantismo in Sicilia
2017
Il testo prende in esame il complesso di materiali editi e inediti (fonti storiche e archivistiche, documenti musicali, testimonianze etnografiche) che attestano la presenza del tarantismo in Sicilia dalla metà del Seicento alla fine dell’Ottocento. Il caso siciliano viene quindi inquadrato nell’ambito dell’ampia letteratura che ruota intorno al fenomeno, a partire dal classico studio di Ernesto De Martino fino al dibattito sull’interpretazione del fenomeno fra i poli dell’esorcismo e della possessione, dovuto soprattutto all’etnomusicologo francese Gilber Rouget. L’analisi viene quindi estesa alla tradizione dei guaritori dei morsi di serpenti (i ciaràuli), che con il tarantismo condividon…
Feeding habits of the Short-toed Eagle Circaetus gallicus during the breeding period in Central Italy
2022
Short-toed Eagle Circaetus gallicus is the only snake eagle that nests in the Palearctic. Its diet has been studied in several European countries and it is essentially based on reptiles. The aims of this work were to characterise the feeding habits of Short-toed Eagle breeding in the Tolfa Mountains (Central Italy) including a comparison of the diet with that of other populations. Moreover, we assessed changes in the diet of the former population using published data collected more than 35 years ago. We monitored five nests and three roosts between 2020 and 2021. Using camera traps and the collection and analysis of feeding remains, a total of 247 prey items were identified. The diet of the…
Two fungal lanostane derivatives as phospholipase A2 inhibitors.
1996
The hydroalcoholic extract of Poria cocos and two lanostane derivatives isolated from it, pachymic acid (1) and dehydrotumulosic acid (2), were active as inhibitors of phospholipase A2 from snake venom when a polarographic method was used. Dehydrotumulosic acid exhibited an IC50 of 0.845 mM. These two compounds are structurally related to certain triterpenoids from Ganoderma and Schinus that have previously been described as competitive inhibitors of phospholipase A2. These comprise a new group of natural potential antiinflammatory agents due to their interaction with that enzyme.
Comments on Guimarães & Sawaya. Pretending to be venomous: is a snake's head shape a trustworthy signal to a predator?
2011
Several species of non-venomous snake are known to flatten their heads when disturbed, and this behaviour has been suggested to be a mimicry of vipers (Arnold & Ovenden 2002, Hailey & Davies 1986, Young et al. 1999). Using plasticine models, Guimaraes & Sawaya (2011) tested the antipredatory function of a triangular head shape in snakes. Their article presents the first published empirical experiment testing the adaptive significance of vipers’ triangular head shape. Guimaraes & Sawaya (2011) found no support for the viper mimicry hypothesis. Accordingly, they concluded that ‘the shape of [the] head seemed not to confer advantage itself’. Although the use of plasticine models is a generally…
The "olfactostriatum" of snakes: a basal ganglia vomeronasal structure in tetrapods.
2005
The olfactostriatum is a portion of the basal ganglia of snakes situated ventromedially to the nucleus accumbens proper. It receives a major vomeronasal input from the nucleus sphericus, the primary target of accessory olfactory bulb efferents. Recently, the ophidian olfactostriatum has been characterized on the basis of chemoarchitecture (distribution of serotonin, neuropeptide Y and tyrosine hydroxylase) and hodology (afferent and efferent connections). In contrast to the nucleus accumbens proper, the olfactostriatum is densely immunoreactive for serotonin and neuropeptide Y and sparsely immunoreactive for tyrosine hydroxylase. The nucleus accumbens proper and the olfactostriatum share mo…
Un groupe statuaire complexe à Autun : essai d’identification
2012
Au cours d’un diagnostic réalisé au nord-ouest de la ville d’Autun, à proximité du rempart d’origine augustéenne, un fragment de groupe statuaire a été trouvé au croisement de deux rues antiques. Reposant sur le sol de circulation, il semble avoir été abandonné au cours de l’Antiquité tardive ou du haut Moyen Age. Il se compose d’un personnage cuirassé (cuirasse musclée) vraisemblablement représenté de dos. Il s’agirait d’une gigantomachie, en ronde-bosse (sculpté sur trois cotés), la face principale a été délitée par la cassure de l’arkose taillée en délit (les bancs géologiques locaux sont impuissants à fournir la hauteur nécessaire à ce groupe). Sur ce drapé, on voit se lover dans une at…
Formation and function of a complement-activating enzyme generated from factors of guinea pig serum and cobra venom
1971
An enzymatic complex can be formed by factors from guinea pig serum and cobra venom, which is able to activate C3 bypassing C1, C4 and C2. Formation and action of the enzyme are described. The action on C3 results in an activation of the terminal complement components and in membrane destruction provided suitable membrane receptors are available.
Protective coloration of European vipers throughout the predation sequence
2020
Antipredator adaptations in the form of animal coloration are common and often multifunctional. European vipers (genus Vipera) have a characteristic dorsal zigzag pattern, which has been shown to serve as a warning signal to potential predators. At the same time, it has been suggested to decrease detection risk, and to cause a motion dazzle or flicker-fusion effect during movement. We tested these hypotheses by asking whether (1) the zigzag pattern decreases detection risk and (2) the detection is dependent on the base coloration (grey or brown) or the snake's posture (coiled, basking form or S-shaped, active form). Additionally, (3) we measured the fleeing speed of adders, Vipera berus, an…