Biology subjects

Pacheco da Silva, V.

Publications and source records attributed to Pacheco da Silva, V..

2 recordsLinked to original sources

bioRxiv2026

Increasing threat: Rhynchophorus ferrugineus invaded mainland America through Uruguay.

Rhynchophorus ferrugineus (Olivier) (Coleoptera: Curculionidae) is one of the most dangerous palm pests worldwide. Here we report the invasion process of R. ferrugineus in Uruguay. Beyond morphological and molecular identification, we infer the geographic origin of the invasive population, describe the succession of introduced and native palms attacked, provide an easy-to-use key to differentiate the invader R. ferrugineus from the native Rhynchophorus palmarum, and model the ecological niche of R. ferrugineus in Uruguay and neighboring countries. First detected in 2022, the Uruguayan population of the weevil is the first to establish on mainland America, following the earlier island records from Curacao and Aruba. Phylogenetic analysis showed that the Uruguayan R. ferrugineus sequences clustered within a single clade, most closely related to sequences from southern China, and clearly distinct from the sequences of Curacao and Aruba, indicating at least two independent introduction events into the Americas from different source regions. After four years, R. ferrugineus has spread across an area of nearly 80,000 square kilometers and in January 2026 it reached Argentina, invading two points near the border with Uruguay. Over the first two years after the invasion, attacks focused on Phoenix canariensis, yet the three most common native palms in Uruguay, Butia odorata, Butia yatay, and Syagrus romanzoffiana, are currently being attacked. The diagnostic key to differentiate the pair R. palmarum / R. ferrugineus is based on three characters: the tip of the rostrum, the tegminal plate, and the ratio between the interocular space and the width of the rostrum at the base. Niche models showed that Uruguay and the neighboring areas of Argentina and Brazil are suitable for R. ferrugineus, and these are precisely the areas where both the highly susceptible P. canariensis and the native B. odorata, B. yatay, and S. romanzoffiana are present. Neighboring countries should therefore be prepared for the expansion of R. ferrugineus in the short term.

zoology↗

bioRxiv2023

EXTRANEURAL RABIES VIRUS INFECTION LEADS TO TISSUE DAMAGE AND CELL DEATH IN MICE

Rabies, a fatal neurological disease caused by Lyssavirus rabies (RABV), poses a significant threat to public health globally. Despite extensive studies on RABV-induced neuropathology, the involvement of extraneural organs during rabies pathogenesis and the tropisms of wild-type strains to different organs remain largely unknown. Here, we investigated the tropism of a dog and bat RABV variant to three different extraneural tissues (kidneys, lungs and liver) and characterized cellular and tissue damage associated with infection in mice over 30 days. Our results reveal that RABV may have a tropism for the kidneys and cause tissue-specific cellular damage. Furthermore, we propose that RABV spreads to extraneural tissues simultaneously with central nervous system (CNS) infection. Understanding the involvement of extraneural organs in rabies pathogenesis may contribute to the development of effective treatment strategies of this fatal disease. AUTHOR SUMMARYRabies is a lethal viral infection that targets the nervous system and generally can be transmitted to humans by bites of infected animals. While there has been significant research focused on how the virus damages the brain, little is known about how the infection affects other organs in the periphery. To address this knowledge gap, we conducted an experimental study to investigate the effects of two distinct wild strains of the virus, one isolated from dogs and the other from bats, on the lungs, liver, and kidneys in mice model of infection. Our findings suggest that the rabies virus infection leads to cell death and produces specific lesions in each of these organs, and we hypothesize that rabies virus may spread to these tissues at the same time as the brain, which possible contributes to the disease outcome. These findings enhance our understanding on how rabies virus targets organs outside the nervous system and its pathology in these different systems.

immunology↗