RESUMO

Geographical barriers like mountain ranges impede genetic exchange among populations, promoting diversification. The effectiveness of these barriers in limiting gene flow varies between lineages due to each species' dispersal modes and capacities. Our understanding of how the Andes orogeny contributes to species diversification comes from well-studied vertebrates and a few arthropods and plants, neglecting organisms unable to fly or walk long distances. Some arachnids, such as Gasteracantha cancriformis, have been hypothesized to disperse long distances via ballooning (i.e. using their silk to interact with the wind). Yet, we do not know how the environment and geography shape its genetic diversity. Therefore, we tested whether the Andes contributed to the diversification of G. cancriformis acting as an absolute or semi-permeable barrier to genetic connectivity between populations of this spider at opposite sides of the mountain range. We sampled thousands of loci across the distribution of the species and implemented population genetics, phylogenetic, and landscape genetic analyses. We identified two genetically distinct groups structured by the Central Andes, and a third less structured group in the Northern Andes that shares ancestry with the previous two. This structure is largely explained by the altitude along the Andes, which decreases in some regions, possibly facilitating cross-Andean dispersal and gene flow. Our findings support that altitude in the Andes plays a major role in structuring populations in South America, but the strength of this barrier can be overcome by organisms with long-distance dispersal modes together with altitudinal depressions.

Las barreras geográficas como las cordilleras montañosas impiden el intercambio genético entre poblaciones, promoviendo la diversificación. La efectividad de estas barreras para limitar el flujo genético varía entre linajes debido a los modos y capacidades de dispersión de cada especie. Nuestra comprensión de cómo la orogenia de los Andes contribuye a la diversificación de especies proviene de vertebrados y algunos artrópodos y plantas bien estudiados, descuidando a los organismos incapaces de volar o caminar grandes distancias. Se ha hipotetizado que algunas arañas, como Gasteracantha cancriformis, se dispersan a grandes distancias mediante la técnica de "ballooning" (es decir, utilizando su seda para interactuar con el viento). Sin embargo, no sabemos cómo el entorno y la geografía han dado forma a su diversidad genética. Por lo tanto, probamos si los Andes contribuyeron a la diversificación de G. cancriformis actuando como una barrera absoluta o permeable para la conectividad genética entre poblaciones de esta araña en lados opuestos de la cordillera. Muestreamos miles de loci a través de la distribución de la especie e implementamos análisis de genética de poblaciones, filogenéticos y de genética del paisaje. Identificamos dos grupos genéticamente distintos estructurados por los Andes Centrales, y un tercer grupo menos estructurado en los Andes del Norte que comparte ascendencia con los dos anteriores. Esta estructura se explica en gran medida por la altitud a lo largo de los Andes, que disminuye en algunas regiones, posiblemente facilitando la dispersión y el flujo genético a través de los Andes. Nuestros hallazgos apoyan que la altitud en los Andes juega un papel importante en la estructuración de las poblaciones en América del Sur, pero la fuerza de esta barrera puede ser superada por organismos con modos de dispersión a larga distancia junto con depresiones altitudinales.

Assuntos

RESUMO

A new species of Mummuciidae, Mummucina huaripampae sp. nov., from Huaripampa, between 3352 and 3568 m a.s.l. in the department of Junín, central Peru, is described and illustrated. This is the first Mummucina species registered for Junín, and the fourth for Peru. With this description, the number of known Mummucina species rises to seven.

Una nueva especie de Mummuciidae, Mummucina huaripampae sp. nov. colectada en Huaripampa, entre 3352 y 3568 m de altitud en el departamento de Junín, en el Perú central, es descrita e ilustrada. Esta es la primera especie de Mummucina registrada para Junín y la cuarta para Perú. Con esta descripción, el número de especies conocidas de Mummucina asciende a siete.

RESUMO

Among the 40 genera of Barychelidae, only nine genera are described from the African continent. Thorell (1899) described Ammonius Thorell, 1899 based on a male from Cameroon. In 1965 Benoit added more information from the holotype, with detailed illustrations of the male palp bulb and the eye group. Since then, few taxonomic revisions or new species of Barychelidae have been proposed from the African continent. Ammonius can be distinguished by the strongly pronounced retrolateral lobe of the male cymbium and the aspect of the bilobed spermathecae of the female. We redescribe the holotype male of A. pupulus Thorell, 1899 and describe the female for the first time. Additionally, a new species is described: Ammonius benoiti sp. nov., from Ivory Coast. The morphology of the tarsal setae is presented through SEM photographs. New distribution records of the genus are provided.

RESUMO

The process of discovering and developing new drugs costs billions of dollars and can take more than ten years. The search for new drugs begins with some form of screening of libraries of chemical compounds that often contain a variety of natural products. Venoms contain toxins with extremely specific functions, therefore being a secretion of great potential in the search for new bioactive compounds. In the era of Next Generation Sequencing and shotgun proteomics, a large number of data of toxins and venom protein sequences from venomous animals have been generated. Thus, there is great interest in applying computational methodologies to facilitate parts of the screening of peptide and proteins for biological activity. To assist in the characterization and search for new toxins and antiviral peptides in arachnid venoms, two computational methods were developed: ArachnoFamTox and EnAVPClass. ArachnoFamTox performs the prediction and classification of arachnid toxins and venom proteins with an approach that uses evolutionary conservation information with Position Specific Scoring Matrices and Hidden Markov Models and is the most specific predictor of toxins among the existing methods and one of the few that classify toxins in families. EnAVPClass predicts antiviral peptides and classifies them according to their mechanism of action. The method uses an approach based on Supervised Machine Learning with Random Forest and Support Vector Machines models and Deep Learning with Long Short Term Memory neural networks. As an example of application of the developed tools, transcriptomes of seven tick species were processed and assembled de novo and the ArachnoFamTox and EnAVPClass tools were used for the prediction and classification of toxins and prediction of Antivirals. A total of 2.069 toxins and venom proteins classified in 13 different families were identified and 47.160 peptides were generated, of which 3.559 antiviral peptides (7.54%) were predicted. Of these, 1.765 were identified as Antivirals that act on virus membranes, 755 on viral replication and 64 on viral assembly. The results show the importance of ticks as promising organisms in the discovery of new antiviral compounds based on their saliva and venom proteins. The tools developed in this work will be available as packages open source in https://github.com/yutakajr after publication and will help in the process of discovering new drugs in silico, classifying families of toxins in arachnids and in the development of new tools.

O processo de descoberta e desenvolvimento de novas drogas tem um custo de bilhões de dólares e pode durar décadas. A procura por novas drogas começa com alguma forma de screening de bibliotecas de compostos químicos que geralmente contém uma variedade de produtos naturais. Os venenos contém toxinas com funções extremamente específicas sendo uma secreção de grande potencial na procura por novos compostos bioativos. Na era do Sequenciamento de Nova Geração e proteômica shotgun, é gerado um grande número de dados de sequências de toxinas e proteínas de veneno de animais venenosos. Assim há um grande interesse em aplicar metodologias computacionais para agilizar partes do processo de screening de sequências de peptídeos e proteínas que possam ter atividade biológica e potencial para serem desenvolvidos novos medicamentos. Para auxiliar na caracterização e busca por novas toxinas e peptídeos antivirais em venenos de aracnídeos, foram desenvolvidos dois métodos computacionais: o ArachnoFamTox e o EnAVPClass. O ArachnoFamTox realiza a predição e classificação de toxinas e proteínas de veneno de aracnídeos com uma abordagem que utiliza informações da conservação evolutiva com Position Specific Scoring Matrices e Hidden Markov Models e é o preditor de toxinas com maior especificidade dentre os métodos existentes e um dos únicos a classificar em famílias de toxinas. O EnAVPClass faz a predição de peptídeos antivirais e classifica-os de acordo com seu mecanismo de ação. O método utiliza uma abordagem baseada em Aprendizagem de Máquina Clássico com modelos de Random Forest e Support Vector Machines e Aprendizagem Profunda com redes neurais do tipo Long Short Term Memory. Como exemplo de aplicação das ferramentas desenvolvidas, foram processados e montados de novo transcriptomas de sete espécies de carrapatos e utilizadas as ferramentas ArachnoFamTox e EnAVPClass para a predição e classificação de toxinas e predição de Antivirais. Foram identificadas 2.069 toxinas e proteínas de veneno classificadas em 13 diferentes famílias e gerados 47.160 peptídeos dos quais foram preditos 3.559 peptídeos antivirais (7.54%). Desses, 1.765 foram identificados como Antivirais que agem nas membranas dos vírus, 755 na replicação viral e 64 na montagem viral. Os resultados evidenciam a importância dos carrapatos como organismos promissores na descoberta de novos compostos antivirais baseados em suas proteínas de saliva e veneno. As ferramentas desenvolvidas neste trabalho ficarão disponíveis como pacotes open source https://github.com/yutakajr após publicação e auxiliarão no processo de descoberta de novas drogas in silico, classificação de famílias de toxinas em aracnídeos e no desenvolvimento de novas ferramentas.

RESUMO

Cell-penetrating peptides (CPPs) comprise a class of short polypeptides that possess the ability to selectively interact with the cytoplasmic membrane of certain cell types, translocate across plasma membranes and accumulate in the cell cytoplasm, organelles (e.g., the nucleus and mitochondria) and other subcellular compartments. CPPs are either of natural origin or de novo designed and synthesized from segments and patches of larger proteins or designed by algorithms. With such intrinsic properties, along with membrane permeation, translocation and cellular uptake properties, CPPs can intracellularly convey diverse substances and nanomaterials, such as hydrophilic organic compounds and drugs, macromolecules (nucleic acids and proteins), nanoparticles (nanocrystals and polyplexes), metals and radionuclides, which can be covalently attached via CPP N- and C-terminals or through preparation of CPP complexes. A cumulative number of studies on animal toxins, primarily isolated from the venom of arthropods and snakes, have revealed the cell-penetrating activities of venom peptides and toxins, which can be harnessed for application in biomedicine and pharmaceutical biotechnology. In this review, I aimed to collate examples of peptides from animal venoms and toxic secretions that possess the ability to penetrate diverse types of cells. These venom CPPs have been chemically or structurally modified to enhance cell selectivity, bioavailability and a range of target applications. Herein, examples are listed and discussed, including cysteine-stabilized and linear, α-helical peptides, with cationic and amphipathic character, from the venom of insects (e.g., melittin, anoplin, mastoparans), arachnids (latarcin, lycosin, chlorotoxin, maurocalcine/imperatoxin homologs and wasabi receptor toxin), fish (pardaxins), amphibian (bombesin) and snakes (crotamine and cathelicidins).

Assuntos

RESUMO

The genus Camillina Berland, 1919 includes 75 valid species which are mainly distributed in South America. However, in Brazil, the knowledge regarding Camillina remains limited and a few contributions to the taxonomy of the genus have been made in the last two decades. Camillina belongs to Zelotinae, a group of gnaphosid spiders which diagnostic character is a preening comb on metatarsi III and IV, and the genus can be recognized by the presence of a prolaterally situated, bifid terminal apophysis and medially situated, recessed embolar base on the male palp and a median epigynal plate. Here, we describe the males and females of three new species: C. suya sp. nov. and C. kuarup sp. nov., both from Fazenda Tanguro, Querência, state of Mato Grosso, Brazil and C. bonaldoi sp. nov. from Parque Nacional de Sete Cidades, Piracuruca, state of Piauí, Brazil.

Assuntos

RESUMO

RESUMEN Presentamos el caso clínico de un paciente adulto joven que consultó por picaduras de araña loxosceles y sus crías, con antecedentes personales importantes de trastorno de ansiedad generalizada y alergia tipo anafilaxia severa por sulfas y AINES. El proceso presentó evolución tórpida inicial con aparición de nuevas lesiones incluso 15 días después del accidente y a pesar de haber utilizado varias alternativas farmacológicas reportadas en la literatura como útiles (colchicina, antihistamínicos, esteroides, anticoagulantes, antibióticos) no había tenido respuesta, hasta la utilización de oxigeno por cámara hiperbárica con la cual frenó la aparición de nuevas lesiones y mejoró la reepitelialización sin necesidad de intervenciones quirúrgicas, con evolución exitosa.

SUMMARY We report the case of a young adult patient who presented bites by Loxosceles spider and its hatchlings with a history of importance of such allergy anaphylaxis severe by sulfa drugs and NSAIDs, generalized anxiety disorder, who presented initial torpid with new lesions even 15 days after the accident and despite having used several pharmacological alternatives reported in the literature as useful (colchicine , antihistamines, steroids, blood thinners, antibiotics) had not been answered, to the use of oxygen for hyperbaric chamber with which brake the appearance of new and improved reepithelialization injury without surgery, with successful evolution.

Assuntos

RESUMO

Spiders of the family Sicariidae pose a serious threat to affected populations, and Loxosceles laeta (Nicolet) is considered the most venomous species. Development of nontoxic olfaction-based spider repellents or traps is hindered by a current lack of knowledge regarding olfactory system function in arachnids. In the present study, general plant odorants and conspecific odors were tested for behavioral responses in L. laeta. Although general odorants triggered neither attraction nor aversion, conspecific odor of the opposite sex caused aversion in females, and attraction in males. These results support the presence of a specific olfactory system for the detection of conspecifics in L. laeta, but suggest the absence of a broadly tuned system for general odorant detection in this species.

Assuntos

RESUMO

Urbanization has a great impact on the diversity of living organisms. Spiders, for example, have been shown to respond negatively (some orb weaving species) and positively (ground dwelling species) to urbanization. The effects of urbanization on crab spiders (Thomisidae) (sit-and-wait predators that generally ambush their prey on flowers and leaves) are not sufficiently known. This paper describes the Thomisidae community that inhabits green patches in a temperate Neotropical city, Cordoba, Argentina, and its surroundings, and ascertains whether there are differences in species richness, abundance and composition between urban and exurban sites. Samples were collected from 30 sites during the summer and spring of 2013 and 2014, using the garden-vacuum method. We compared the abundance, richness and composition of Thomisidae among three habitat categories (urban, suburban and external). Seven species in three genera, Misumenops, Wechselia and Tmarus, were detected. Misumenops was the most abundant genus in Córdoba, and Tmarus elongates Mello-Leitão, 1929 was collected in Argentina for the first time. The abundance, richness and composition of thomisid spiders did not differ between habitat categories, indicating that urbanization does not have a negative effect on the communities of these spiders in open green spaces. Site variability, on the other hand, does, suggesting that local factors may be more relevant than broad-scale factors to explain community patterns in this family.(AU)

Assuntos

RESUMO

Urbanization has a great impact on the diversity of living organisms. Spiders, for example, have been shown to respond negatively (some orb weaving species) and positively (ground dwelling species) to urbanization. The effects of urbanization on crab spiders (Thomisidae) (sit-and-wait predators that generally ambush their prey on flowers and leaves) are not sufficiently known. This paper describes the Thomisidae community that inhabits green patches in a temperate Neotropical city, Cordoba, Argentina, and its surroundings, and ascertains whether there are differences in species richness, abundance and composition between urban and exurban sites. Samples were collected from 30 sites during the summer and spring of 2013 and 2014, using the garden-vacuum method. We compared the abundance, richness and composition of Thomisidae among three habitat categories (urban, suburban and external). Seven species in three genera, Misumenops, Wechselia and Tmarus, were detected. Misumenops was the most abundant genus in Córdoba, and Tmarus elongates Mello-Leitão, 1929 was collected in Argentina for the first time. The abundance, richness and composition of thomisid spiders did not differ between habitat categories, indicating that urbanization does not have a negative effect on the communities of these spiders in open green spaces. Site variability, on the other hand, does, suggesting that local factors may be more relevant than broad-scale factors to explain community patterns in this family.

Assuntos

RESUMO

Abstract: Acute generalized exanthematous pustulosis (AGEP) is an acute febrile rash, usually induced by drugs, which recently has been linked to spider bite. We report a case of a male patient, 48 years old, with an erythematous rash accompanied by fever and small non-follicular pustules. He reported previous pain in the buttock with the onset of a necrotic plaque. The lesion was compatible with spider bite of the genus Loxosceles. According to the EuroSCAR group instrument, the patient scored +10 indicating definite diagnosis of AGEP. As the patient had a compatible lesion and had no other triggers of AGEP, in an Loxosceles endemic area, the AGEP would be associated with spider bite, as described in other publications.

Assuntos

RESUMO

BACKGROUND: Scorpionism is a public health problem in various regions of the world, being Mexico the country with the highest number of cases. Clinical manifestations range from local symptoms to severe disease with an impact on cardiovascular, respiratory and neurological level, and even death. There are no reports of acute flaccid paralysis as a manifestation of the clinical picture of the scorpion sting of the Centruroides gender, Family Buthidae, highly toxic, causes high rates of morbidity and mortality in our region. CLINICAL CASE: We documented a case of scorpionism, caused by a scorpion gender Buthidae, Centruroides family, which caused acute flaccid paralysis, after resolution of other severe manifestations. There is only one case report of scorpionism that produces acute flaccid paralysis in the literature, but it is related to the Parabuthus scorpion, endemic of South Africa. CONCLUSIONS: The knowledge of this complication, new for our region, will maximize efforts to diagnose and appropriately manage this symptoms, with the adequate application of the specific fabotherapy and advanced life support for proper survival in the patients with compromise of vital functions and imminent risk of death mainly by respiratory failure.

Introducción: el alacranismo es un problema de salud pública en diversas regiones del mundo, siendo México el país que tiene mayor número de casos. Las manifestaciones clínicas oscilan desde sintomatología local hasta cuadros graves con repercusiones a nivel cardiovascular, respiratorio y neurológico, e incluso la muerte. No existen reportes de parálisis flácida como una manifestación del cuadro clínico por picadura del alacrán del género Centruroides, familia Buthidae, especie altamente tóxica, endémica y causante de altos índices de morbimortalidad en nuestra región. Caso clínico: documentamos un caso de alacranismo grave, provocado por escorpión de la familia Buthidae del género Centruroides, que causó parálisis flácida aguda, posterior a resolución de otras manifestaciones severas. Solo existe un reporte de caso de alacranismo que produce parálisis flácida aguda en la literatura médica, pero relacionado con el escorpión de la familia Parabuthus, endémico de Sudáfrica, el cual no es endémico en México. Conclusiones: conocer esta complicación, nueva para nuestra región, permitirá maximizar esfuerzos para diagnosticar y manejar oportunamente esta entidad con la aplicación temprana de faboterápico específico y soporte vital avanzado.

Assuntos

RESUMO

Arachnida is the largest class among the arthropods, constituting over 60,000 described species (spiders, mites, ticks, scorpions, palpigrades, pseudoscorpions, solpugids and harvestmen). Many accidents are caused by arachnids, especially spiders and scorpions, while some diseases can be transmitted by mites and ticks. These animals are widely dispersed in urban centers due to the large availability of shelter and food, increasing the incidence of accidents. Several protein and non-protein compounds present in the venom and saliva of these animals are responsible for symptoms observed in envenoming, exhibiting neurotoxic, dermonecrotic and hemorrhagic activities. The phylogenomic analysis from the complementary DNA of single-copy nuclear protein-coding genes shows that these animals share some common protein families known as neurotoxins, defensins, hyaluronidase, antimicrobial peptides, phospholipases and proteinases. This indicates that the venoms from these animals may present components with functional and structural similarities. Therefore, we described in this review the main components present in spider and scorpion venom as well as in tick saliva, since they have similar components. These three arachnids are responsible for many accidents of medical relevance in Brazil. Additionally, this study shows potential biotechnological applications of some components with important biological activities, which may motivate the conducting of further research studies on their action mechanisms.(AU)

Assuntos

RESUMO

Arachnida is the largest class among the arthropods, constituting over 60,000 described species (spiders, mites, ticks, scorpions, palpigrades, pseudoscorpions, solpugids and harvestmen). Many accidents are caused by arachnids, especially spiders and scorpions, while some diseases can be transmitted by mites and ticks. These animals are widely dispersed in urban centers due to the large availability of shelter and food, increasing the incidence of accidents. Several protein and non-protein compounds present in the venom and saliva of these animals are responsible for symptoms observed in envenoming, exhibiting neurotoxic, dermonecrotic and hemorrhagic activities. The phylogenomic analysis from the complementary DNA of single-copy nuclear protein-coding genes shows that these animals share some common protein families known as neurotoxins, defensins, hyaluronidase, antimicrobial peptides, phospholipases and proteinases. This indicates that the venoms from these animals may present components with functional and structural similarities. Therefore, we described in this review the main components present in spider and scorpion venom as well as in tick saliva, since they have similar components. These three arachnids are responsible for many accidents of medical relevance in Brazil. Additionally, this study shows potential biotechnological applications of some components with important biological activities, which may motivate the conducting of further research studies on their action mechanisms.

RESUMO

Arachnida is the largest class among the arthropods, constituting over 60,000 described species (spiders, mites, ticks, scorpions, palpigrades, pseudoscorpions, solpugids and harvestmen). Many accidents are caused by arachnids, especially spiders and scorpions, while some diseases can be transmitted by mites and ticks. These animals are widely dispersed in urban centers due to the large availability of shelter and food, increasing the incidence of accidents. Several protein and non-protein compounds present in the venom and saliva of these animals are responsible for symptoms observed in envenoming, exhibiting neurotoxic, dermonecrotic and hemorrhagic activities. The phylogenomic analysis from the complementary DNA of single-copy nuclear protein-coding genes shows that these animals share some common protein families known as neurotoxins, defensins, hyaluronidase, antimicrobial peptides, phospholipases and proteinases. This indicates that the venoms from these animals may present components with functional and structural similarities. Therefore, we described in this review the main components present in spider and scorpion venom as well as in tick saliva, since they have similar components. These three arachnids are responsible for many accidents of medical relevance in Brazil. Additionally, this study shows potential biotechnological applications of some components with important biological activities, which may motivate the conducting of further research studies on their action mechanisms.(AU)

Assuntos

RESUMO

Arachnida is the largest class among the arthropods, constituting over 60,000 described species (spiders, mites, ticks, scorpions, palpigrades, pseudoscorpions, solpugids and harvestmen). Many accidents are caused by arachnids, especially spiders and scorpions, while some diseases can be transmitted by mites and ticks. These animals are widely dispersed in urban centers due to the large availability of shelter and food, increasing the incidence of accidents. Several protein and non-protein compounds present in the venom and saliva of these animals are responsible for symptoms observed in envenoming, exhibiting neurotoxic, dermonecrotic and hemorrhagic activities. The phylogenomic analysis from the complementary DNA of single-copy nuclear protein-coding genes shows that these animals share some common protein families known as neurotoxins, defensins, hyaluronidase, antimicrobial peptides, phospholipases and proteinases. This indicates that the venoms from these animals may present components with functional and structural similarities. Therefore, we described in this review the main components present in spider and scorpion venom as well as in tick saliva, since they have similar components. These three arachnids are responsible for many accidents of medical relevance in Brazil. Additionally, this study shows potential biotechnological applications of some components with important biological activities, which may motivate the conducting of further research studies on their action mechanisms.

Assuntos