Scorpions from the primeval subgenus Archaeotityus produce putative homologs of Tityus serrulatus toxins active on voltage-gated sodium channels

It has been proposed that the subgenus Archaeotityus comprises the most ancient species group within the medically important scorpion genus Tityus. cDNA encoding sodium-channel active toxins from the type species of this subgenus, Tityus clathratus (central Venezuela), have been isolated and sequenced. Two cDNAs were retrieved that encoded 61 amino acid-long putative neurotoxins named Tcl1 and Tcl2. Sequence identity was highest (87%) when both were compared with -toxin Ts1 from the Brazilian scorpion Tityus serrulatus and its homologs from T. bahiensis, T. stigmurus, and T. costatus. A Bayesian analysis indicated statistical support for the grouping of T. clathratus Tcl1 and Tcl2 with Brazilian gamma-like -toxins, reinforcing previous phylogenetic studies which suggested an evolutionary relationship between the subgenus Archaeotityus and scorpion species inhabiting southeast South America belonging to the subgenus Tityus.

Scorpions from the primeval subgenus Archaeotityus produce putative homologs of Tityus serrulatus toxins active on voltage-gated sodium channels

It has been proposed that the subgenus Archaeotityus comprises the most ancient species group within the medically important scorpion genus Tityus. cDNA encoding sodium-channel active toxins from the type species of this subgenus, Tityus clathratus (central Venezuela), have been isolated and sequenced. Two cDNAs were retrieved that encoded 61 amino acid-long putative neurotoxins named Tcl1 and Tcl2. Sequence identity was highest (87%) when both were compared with -toxin Ts1 from the Brazilian scorpion Tityus serrulatus and its homologs from T. bahiensis, T. stigmurus, and T. costatus. A Bayesian analysis indicated statistical support for the grouping of T. clathratus Tcl1 and Tcl2 with Brazilian gamma-like -toxins, reinforcing previous phylogenetic studies which suggested an evolutionary relationship between the subgenus Archaeotityus and scorpion species inhabiting southeast South America belonging to the subgenus Tityus.

Second record of Tityus bahiensis (Scorpiones, Buthidae) from Venezuela: epidemiological implications

This work reports the second record of the scorpion Tityus bahiensis Perty from Venezuela. The specimen was found alive in a wardrobe at a hotel resort in Margarita Island, northeastern Venezuela. Morphological characterization allowed its assignment to the Tityus bahiensis population inhabiting the southernmost area of the species' geographic range, e.g. the state of São Paulo in Brazil, northern Argentina and Paraguay. The fact that the only available Venezuelan antiscorpion (anti-Tityus discrepans) serum does not neutralize the effects of alpha- and beta-toxin from Tityus serrulatus venom (which resembles in composition that of T. bahiensis) constitutes a warning to local clinicians confronted with envenomations by noxious species transported to Venezuela from Brazil by human agency.

Felino doméstico como transmissor da esporotricose em trabalhador rural- relato de caso

ABSTRACT Sporotrichosis is a mycosis caused by the geophilic fungus Sporothrixschenckii that can infect different species of animals, including humans. The mycosis has a worldwide distribution, mainly in the tropical and subtropical regions. The infection is usually associated with the traumatic inoculation of soil, vegetables or organic materials contaminated by the fungus, being, therefore, considered an occupational mycosis, affecting mainly rural workers. The zoonotic potential of the domestic feline has been recognized since the 1980s, due to the presence of a great number of microorganisms present in this animal species. Concerning the important epidemiological role of the domestic feline, this study describes a case of cutaneous sporotrichosis with ascendant lymphangitis in a rural worker contaminated by an asymptomatic feline. One 40-year-old human male presented nodular injuries 15 days after being scratched by a cat. Samples of lesion exudates were collected for mycological analysis, which resulted in the isolation of the S. schenckii. After the diagnostic confirmation of sporotrichosis, treatment with cetoconazol was started, which resulted in the regression of the lesions. This study emphasizes the importance of the domestic feline as an important carrier of the sporotrichosis agent for humans.

RESUMO A esporotricose é uma micose causada pelo fungo geofílico Sporothrix schenckii que pode infectar diferentes espécies de animais, inclusive o homem. A micose tem distribuição mundial, principalmente nas regiões tropicais e subtropicais. A infecção está, normalmente, associada com a inoculação traumática de solo, vegetais ou materiais orgânicos contaminados pelo fungo, sendo, portanto, considerada uma micose ocupacional, afetando, principalmente trabalhadores rurais. O potencial zoonótico do felino doméstico tem sido reconhecido desde a década de 80, possivelmente devido ao grande número do organismo presente nessa espécie animal. Em vista do importante papel epidemiológico do felino doméstico, este estudo descreve um caso de esporotricose cutânea com linfangite ascedente em um trabalhador rural contaminado por um felino assintomático. Um humano, com 40 anos, do sexo masculino, apresentou lesões nodulares 15 dias após ter sido arranhado por um gato hígido. Foram coletadas amostras de exsudato das lesões para análise micológica, a qual resultou no isolamento do S. schenckii. Após a confirmação do diagnóstico de esporotricose, foi iniciado o tratamento com o cetoconazol que resultou na regressão das lesões. O estudo ressalta a importância do felino doméstico como importante carreador do agente da esporotricose para o homem.

The first report of Tityus (Scorpiones: Buthidae) in Anzoátegui State, Venezuela: a new species

Tityus gonzalespongai n. sp. is a species endemic to the high mountains of Anzoátegui State, Venezuela. It is found between 1,600 and 2,200 m in ''La Laguna'' mountain. Its habitat includes the area of ''Bosque Húmedo Montano Bajo'' with the type of vegetation of ''Bosque Ombrófilo Montano Siempreverde'' (''Bosques Nublados Costeros'' that includes the ''Subpáramos Arbustivos''). It is distinguished from other Tityus species (T. caripitensis, T. monaguensis, and T. nororientalis) by the following characteristics: 1- the disposition of the trichobothria in the pedipalps; 2- ventral keels of the caudal segments of the metasoma (segment II, double and parallel in the proximal two thirds, then convergent and finally divergent in the base; segments III and IV, double and parallel in the basal third, then convergent in a single keel that divides in the base); 3- the number of lines of denticles of the movable finger of the right pedipalp (male = 14; female = 14); 4- pectineous teeth (right/left: male = 15/15: female = 16/15); 5- color: movable and fixed fingers dark brown; prosoma and metasoma, ochre; caudal segment IV, slightly darker than the previous ones; V and the telson, dark brown. T. gonzalespongai belongs to the ''androcottoides'' group and presents a marked sexual dimorphism. It is the first species of the Tityus genus described and reported in Anzoátegui State, expanding this taxa distribution in Venezuela.