New data on spiders (Arachnida, Araneae) of Türkiye, with descriptions of four new species

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  New data on spiders (Arachnida, Araneae) of Türkiye, with descriptions of four new species Abstract New taxonomic and faunistic data on Turkish spiders are presented. Four species are described as new to science: Cybaeus anatolicus sp. nov . (♀; Konya) [ Cybaeidae ], Dictyna caligaformis sp. nov . (♂♀; Bursa) [ Dictynidae ], Leptonetela ayvaensis sp. nov . (♂♀; Bursa), and L. oylatensis sp. nov . (♂; Bursa) [ Leptonetidae ]. Except for Cybaeus anatolicus sp. nov ., the remaining new species were collected in caves. Additionally, Drassodes robatus Roewer, 1961 [ Gnaphosidae ] is recorded from Türkiye for the first time, and an unusual variation in the shape of the retrolateral tibial apophysis is documented in an unidentified congener. Additional illustrations are provided for Cataleptoneta aydintopcui Demircan, 2020 [ Leptonetidae ] and Pterotricha kochi (O. Pickard-Cambridge, 1872) [ Gnaphosidae ], for which new localities in Türkiye are reported, as well as for ...

In vivo biodistribution of Loxosceles intermedia venom in animal models with different pathological outcomes

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In vivo biodistribution of Loxosceles intermedia venom in animal models with different pathological outcomes

Abstract

Spiders of the Loxosceles spp. genus have a wide geographic distribution and are among the main causes of arachnidism in Brazil. Despite advances in venom characterization, fundamental aspects such as its in vivo kinetics and biodistribution remain little understood. This study aimed to investigate the biodistribution of Loxosceles intermedia spider venom through radiolabeling with technetium-99 metastable (99ᵐTc). Radiolabeling efficiency was evaluated using paper chromatography and C18 column, and effectiveness was assessed by SDS-PAGE. Biological activity after radiolabeling was verified through an in vitro sphingomyelinase activity assay and by evaluating dermonecrotic and edematogenic effects in rabbits. The results showed that most venom proteins were efficiently radiolabeled and that the venom remained biologically active after radiolabeling, allowing its distribution to be tracked in mice and rabbits. In both models, the venom concentrated at the injection site and was predominantly biodistributed to the kidneys and bladder. These findings are relevant given the distinct pathophysiological profiles of the animal models used. This is the first study to evaluate, in real time and in live animals, the biodistribution of L. intermedia venom through radiolabeling, and it may provide valuable data for understanding its mechanisms of action and improved the diagnostic of loxoscelism.
Da Silva Moreira, R., Pires, L. O., Cardoso Cunha, L., Fiorini de Carvalho, I. A., Chávez-Olórtegui, C., Minozzo, J. C., Rocha, M. N., Cardoso, V. N., Antunes Fernandes, S. O., & Felicori, L. F. (2025). In vivo biodistribution of Loxosceles intermedia venom in animal models with different pathological outcomes. Toxicon, 108619. https://doi.org/10.1016/j.toxicon.2025.108619