RESUMEN

Angiostrongylus vasorum is a metastrongylid parasite infecting wild canids and domestic dogs. Its patchy distribution, high pathogenicity and taxonomical classification makes the evolutionary history of A. vasorum intriguing and important to study. First larval stages of A. vasorum were recovered from feces of two grey foxes, Urocyon cinereoargenteus, from Costa Rica. Sequencing and phylogenetic and haplotypic analyses of the ITS2, 18S and cytochrome oxidase subunit 1 (cox1) fragments were performed. Then p- and Nei´s genetic distance, nucleotide substitution rates and species delimitation analyses were conducted with cox1 data of the specimens collected herein and other Angiostrongylus spp. Cophylogenetic congruence and coevolutionary events of Angiostrongylus spp. and their hosts were evaluated using patristic and phenetic distances and maximum parsimony reconciliations. Specimens from Costa Rica clustered in a separate branch from European and Brazilian A. vasorum sequences in the phylogenetic and haplotype network analyses using the ITS2 and cox1 data. In addition, cox1 p-distance of the sequences derived from Costa Rica were up to 8.6 % different to the ones from Europe and Brazil, a finding mirrored in Nei´s genetic distance PCoA. Species delimitation analysis supported a separate group with the sequences from Costa Rica, suggesting that these worms may represent cryptic variants of A. vasorum, a new undescribed taxon or Angiocaulus raillieti, a synonym species of A. vasorum described in Brazil. Moreover, nucleotide substitution rates in A. vasorum were up to six times higher than in the congener Angiostrongylus cantonensis. This finding and the long time elapsed since the last common ancestor between both species may explain the larger diversity in A. vasorum. Finally, cophylogenetic congruence was observed between Angiostrongylus spp. and their hosts, with cospeciation events occurring at deeper taxonomic branching of host order. Altogether, our data suggest that the diversity of the genus Angiostrongylus is larger than expected, since additional species may be circulating in wild canids from the Americas.

Asunto(s)

Angiostrongylus , Filogenia , Animales , Angiostrongylus/genética , Angiostrongylus/clasificación , Angiostrongylus/aislamiento & purificación , Costa Rica , Variación Genética , Infecciones por Strongylida/parasitología , Infecciones por Strongylida/veterinaria , Infecciones por Strongylida/epidemiología , Análisis de Secuencia de ADN , Heces/parasitología , Zorros/parasitología , Complejo IV de Transporte de Electrones/genética , ADN de Helmintos/genética , Haplotipos , ADN Espaciador Ribosómico/genética , Américas , Perros

RESUMEN

Angiostrongylus costaricensis is a zoonotic parasitic nematode described for the first time in 1971 by Pedro Morera and Rodolfo Céspedes in Costa Rica. This parasite causes an infection known as abdominal angiostrongyliasis, affecting mainly school-aged children and young adults. Infection with A. costaricensis has been associated with a myriad of rodent and mollusk species in the Americas and the Caribbean, as its natural hosts and reservoirs. In this commemorative review, we highlight the extensive research collected through a 50-year journey, which includes ecological, pathological, and molecular studies on A. costaricensis and its implicated disease. We also identify major knowledge gaps in its evolutionary history, the ecological role of imported and invasive mollusk species, and immune response. We propose that the advent of -omics analyses will allow us to gather novel information regarding A. costaricensis biology and infection dynamics, as well as to promote the design of much-needed sensitive and specific diagnostic tools.

Asunto(s)

Angiostrongylus/clasificación , Reservorios de Enfermedades/parasitología , Moluscos/parasitología , Enfermedades de los Roedores/parasitología , Infecciones por Strongylida/parasitología , Américas/epidemiología , Angiostrongylus/genética , Angiostrongylus/inmunología , Angiostrongylus/fisiología , Animales , Región del Caribe/epidemiología , Especificidad del Huésped , Humanos , Inmunidad , Especies Introducidas , Larva , Estadios del Ciclo de Vida , Roedores , Infecciones por Strongylida/diagnóstico , Infecciones por Strongylida/epidemiología , Infecciones por Strongylida/patología , Zoonosis

RESUMEN

Currently, there are 21 species of Angiostrongylus that parasitize the pulmonary or mesenteric arteries of wild and domestic rodents, felids, canids and human. Species of Angiostrongylus have cosmopolitan distribution covering tropical, subtropical and temperate regions. The procyonid Nasua nasua (coati) is a reservoir host for a wide variety of parasites that may be harmful to its populations or may contain etiological agents with zoonotic potential. In urban areas, coatis are usually found in close association with humans and domestic animals. We morphologically and molecularly characterized a new species of Angiostrongylus found in N. nasua in a protected area within Belo Horizonte, Brazil. The new species of Angiostrongylus differs from other species of the same genus in terms of the length and bifurcation level of the lateral and ventral rays, the length of spicules and female tail morphology. Molecular phylogenetic results based on the mitochondrial cytochrome c oxidase subunit 1 gene suggest that the newly identified species belongs to a genetic lineage that is separate from other species of Angiostrongylus. This new species was collected from the mesenteric arteries of N. nasua. It was named Angiostrongylus minasensis n. sp..

Asunto(s)

Angiostrongylus , Procyonidae/parasitología , Angiostrongylus/anatomía & histología , Angiostrongylus/clasificación , Angiostrongylus/genética , Animales , Brasil , Femenino , Masculino , Filogenia , Reacción en Cadena de la Polimerasa , Población Urbana

RESUMEN

Abstract Currently, there are 21 species of Angiostrongylus that parasitize the pulmonary or mesenteric arteries of wild and domestic rodents, felids, canids and human. Species of Angiostrongylus have cosmopolitan distribution covering tropical, subtropical and temperate regions. The procyonid Nasua nasua (coati) is a reservoir host for a wide variety of parasites that may be harmful to its populations or may contain etiological agents with zoonotic potential. In urban areas, coatis are usually found in close association with humans and domestic animals. We morphologically and molecularly characterized a new species of Angiostrongylus found in N. nasua in a protected area within Belo Horizonte, Brazil. The new species of Angiostrongylus differs from other species of the same genus in terms of the length and bifurcation level of the lateral and ventral rays, the length of spicules and female tail morphology. Molecular phylogenetic results based on the mitochondrial cytochrome c oxidase subunit 1 gene suggest that the newly identified species belongs to a genetic lineage that is separate from other species of Angiostrongylus. This new species was collected from the mesenteric arteries of N. nasua. It was named Angiostrongylus minasensis n. sp..

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Resumo Existem 21 espécies de Angiostrongylus que parasitam as artérias pulmonares ou mesentéricas de roedores silvestres e domésticos, felídeos, canídeos e homem. Espécies de Angiostrongylus têm uma distribuição cosmopolita que abrange regiões tropicais, subtropicais e temperadas. O procionídeo Nasua nasua (quati) é hospedeiro de vários parasitos que podem ser prejudiciais para suas populações ou conter agentes etiológicos com potencial zoonótico. Nas áreas urbanas, os quatis podem ser encontrados em estreita associação com seres humanos e animais domésticos. Nós caracterizamos morfológica e molecularmente uma nova espécie de Angiostrongylus encontrada em N. nasua de uma área protegida na cidade de Belo Horizonte, Brasil. A nova espécie de Angiostrongylus difere de outras espécies do mesmo gênero pelo comprimento e nível de bifurcação dos raios lateral e ventral, o comprimento dos espículos e a morfologia da cauda da fêmea. Resultados moleculares e filogenéticos baseados no gene mitocondrial citocromo c oxidase subunidade 1 indicam que a espécie recém-identificada pertence a uma linhagem genética separada de outras espécies de Angiostrongylus. O presente relato descreve uma nova espécie de Angistrongylus coletada das artérias mesentéricas de N. nasua, denominada Angiostrongylus minasensis n. sp..

Asunto(s)

Animales , Masculino , Femenino , Procyonidae/parasitología , Angiostrongylus/anatomía & histología , Angiostrongylus/clasificación , Angiostrongylus/genética , Filogenia , Población Urbana , Brasil , Reacción en Cadena de la Polimerasa

RESUMEN

Many molluscs may be infected with angiostrongylid larvae. Following the histopathological diagnosis of abdominal angiostrongyliasis in a grape farmer from southern Brazil, molluscs in the area were investigated. During a nocturnal search, 245 specimens of slugs were collected and identified as the invasive Chinese slug Meghimatium pictum. Angiostrongylus costaricensis worms were recovered from mice that were experimentally infected with larvae obtained from 11 (4.5%) of the molluscs. This study presents the first report of M. pictum being identified as an intermediate host for A. costaricensis. Most of the slugs were collected from grape plants, which suggests that transmission may be associated with grape consumption.

Asunto(s)

Angiostrongylus/aislamiento & purificación , Gastrópodos/parasitología , Infecciones por Strongylida/parasitología , Vitis/parasitología , Angiostrongylus/clasificación , Angiostrongylus/genética , Animales , Brasil , Gastrópodos/clasificación , Humanos , Especies Introducidas , Ratones , Infecciones por Strongylida/transmisión

RESUMEN

BACKGROUND Angiostrongyliasis is an infection caused by nematode worms of the genus Angiostrongylus. The adult worms inhabit the pulmonary arteries, heart, bronchioles of the lung, or mesenteric arteries of the caecum of definitive host. Of a total of 23 species of Angiostrongylus cited worldwide, only nine were registered in the American Continent. Two species, A. cantonensis and A. costaricensis, are considered zoonoses when the larvae accidentally parasitise man. OBJECTIVES In the present study, geographical and chronological distribution of definitive hosts of Angiostrongylus in the Americas is analysed in order to observe their relationship with disease reports. Moreover, the role of different definitive hosts as sentinels and dispersers of infective stages is discussed. METHODS The study area includes the Americas. First records of Angiostrongylus spp. in definitive or accidental hosts were compiled from the literature. Data were included in tables and figures and were matched to geographic information systems (GIS). FINDINGS Most geographical records of Angiostrongylus spp. both for definitive and accidental hosts belong to tropical areas, mainly equatorial zone. In relation to those species of human health importance, as A. cantonensis and A. costaricensis, most disease cases indicate a coincidence between the finding of definitive host and disease record. However, in some geographic site there are gaps between report of definitive host and disease record. In many areas, human populations have invaded natural environments and their socioeconomic conditions do not allow adequate medical care. MAIN CONCLUSIONS Consequently, many cases for angiostrongyliasis could have gone unreported or unrecognised throughout history and in the nowadays. Moreover, the population expansion and the climatic changes invite to make broader and more complete range of observation on the species that involve possible epidemiological risks. This paper integrates and shows the current distribution of Angiostrongylus species in America, being this information very relevant for establishing prevention, monitoring and contingency strategies in the region.

Asunto(s)

Infecciones por Strongylida/parasitología , Infecciones por Strongylida/epidemiología , Angiostrongylus/clasificación , Reservorios de Enfermedades , Notificación de Enfermedades , Sistemas de Información Geográfica

RESUMEN

BACKGROUND: Angiostrongyliasis is an infection caused by nematode worms of the genus Angiostrongylus. The adult worms inhabit the pulmonary arteries, heart, bronchioles of the lung, or mesenteric arteries of the caecum of definitive host. Of a total of 23 species of Angiostrongylus cited worldwide, only nine were registered in the American Continent. Two species, A. cantonensis and A. costaricensis, are considered zoonoses when the larvae accidentally parasitise man. OBJECTIVES: In the present study, geographical and chronological distribution of definitive hosts of Angiostrongylus in the Americas is analysed in order to observe their relationship with disease reports. Moreover, the role of different definitive hosts as sentinels and dispersers of infective stages is discussed. METHODS: The study area includes the Americas. First records of Angiostrongylus spp. in definitive or accidental hosts were compiled from the literature. Data were included in tables and figures and were matched to geographic information systems (GIS). FINDINGS: Most geographical records of Angiostrongylus spp. both for definitive and accidental hosts belong to tropical areas, mainly equatorial zone. In relation to those species of human health importance, as A. cantonensis and A. costaricensis, most disease cases indicate a coincidence between the finding of definitive host and disease record. However, in some geographic site there are gaps between report of definitive host and disease record. In many areas, human populations have invaded natural environments and their socioeconomic conditions do not allow adequate medical care. MAIN CONCLUSIONS: Consequently, many cases for angiostrongyliasis could have gone unreported or unrecognised throughout history and in the nowadays. Moreover, the population expansion and the climatic changes invite to make broader and more complete range of observation on the species that involve possible epidemiological risks. This paper integrates and shows the current distribution of Angiostrongylus species in America, being this information very relevant for establishing prevention, monitoring and contingency strategies in the region.

Asunto(s)

Angiostrongylus/clasificación , Interacciones Huésped-Parásitos , Infecciones por Strongylida/parasitología , Américas/epidemiología , Distribución Animal , Animales , Notificación de Enfermedades , Reservorios de Enfermedades , Sistemas de Información Geográfica , Humanos , Infecciones por Strongylida/epidemiología

RESUMEN

Angiostrongylus costaricensis is a zoonotic parasitic nematode that causes abdominal or intestinal angiostrongyliasis in humans. It is endemic to the Americas. Although the mitochondrial genome of the Brazil taxon has been published, there is no available mitochondrial genome data on the Costa Rica taxon. We report here the complete mitochondrial genome of the Costa Rica taxon and its genetic differentiation from the Brazil taxon. The whole mitochondrial genome was obtained from next-generation sequencing of genomic DNA. It had a total length of 13,652 bp, comprising 36 genes (12 protein-coding genes-PCGs, 2 rRNA and 22 tRNA genes) and a control region (A + T rich non-coding region). It is longer than that of the Brazil taxon (13,585 bp). The larger mitogenome size of the Costa Rica taxon is due to the size of the control region as the Brazil taxon has a shorter length (265 bp) than the Costa Rica taxon (318 bp). The size of 6 PCGs and the start codon for ATP6, CYTB and NAD5 genes are different between the Costa Rica and Brazil taxa. Additionally, the two taxa differ in the stop codon of 6 PCGs. Molecular phylogeny based on 12 PCGs was concordant with two rRNA, 22 tRNA and 36 mitochondrial genes. The two taxa have a genetic distance of p = 16.2% based on 12 PCGs, p = 15.3% based on 36 mitochondrial genes, p = 13.1% based on 2 rRNA genes and p = 10.7% based on 22 tRNA genes, indicating status of sibling species. The Costa Rica and Brazil taxa of A. costaricensis are proposed to be accorded specific status as members of a species complex.

Asunto(s)

Angiostrongylus/genética , Genoma Mitocondrial , Angiostrongylus/clasificación , Animales , Brasil , Filogenia

RESUMEN

Angiostrongylus costaricensis is a parasitic nematode that can cause severe gastrointestinal disease, known as abdominal angiostrongiliasis, in humans. This paper presents the characterization of first- and third-stage larvae and male and female adult worms of A. costaricensis by scanning electron and light microscopy. Several novel anatomical structures were identified by scanning electron microscopy, including details of the cuticular striations of the spicules in male worms and a protective flap of the cuticle covering the vulvar aperture in female worms. Other taxonomic features revealed by light microscopy include the gubernaculum and the esophageal-intestinal valve. The use of two microscopy techniques allowed a detailed characterization of the morphology of this nematode. A number of previously identified taxonomic features, such as the striated nature of the spicules and the lateral alae were confirmed; however, the use of scanning electron microscopy resulted in a reassessment of the correct number of papillae distributed around the oral opening and behind the cloacal opening. These observations, in combination with light microscopy-based characterization of the gubernaculum and esophageal valves, have allowed a more detailed description of this nematode taxonomy.

Asunto(s)

Angiostrongylus/ultraestructura , Microscopía Electrónica de Rastreo , Angiostrongylus/clasificación , Animales , Femenino , Masculino

RESUMEN

Angiostrongylus felineus n. sp. (Nematoda, Metastrongyloidea), parasitic in Puma (Herpailurus) yagouaroundi (É. Geoffroy, 1803) (Carnivora, Felidae) from the municipality of Juiz de Fora, Minas Gerais state, Brazil, is described and illustrated herein. Angiostrongylus felineus n. sp. differs from all congeneric species by having the anterior extremity with accentuated cuticular expansion and by smaller size of spicules. This study describes for the first time a species of Angiostrongylus in a wild Felidae in Brazil.

Asunto(s)

Angiostrongylus/clasificación , Arteria Pulmonar/parasitología , Puma/parasitología , Infecciones por Strongylida/veterinaria , Angiostrongylus/anatomía & histología , Angiostrongylus/ultraestructura , Animales , Brasil/epidemiología , Femenino , Masculino , Caracteres Sexuales , Infecciones por Strongylida/epidemiología , Infecciones por Strongylida/parasitología

RESUMEN

Angiostrongylus costaricensis is a nematode that causes abdominal angiostrongyliasis, a widespread human parasitism in Latin America. This study aimed to characterize the protease profiles of different developmental stages of this helminth. First-stage larvae (L1) were obtained from the faeces of infected Sigmodon hispidus rodents and third-stage larvae (L3) were collected from mollusks Biomphalaria glabrata previously infected with L1. Adult worms were recovered from rodent mesenteric arteries. Protein extraction was performed after repeated freeze-thaw cycles followed by maceration of the nematodes in 40 mM Tris base. Proteolysis of gelatin was observed by zymography and found only in the larval stages. In L3, the gelatinolytic activity was effectively inhibited by orthophenanthroline, indicating the involvement of metalloproteases. The mechanistic class of the gelatinases from L1 could not be precisely determined using traditional class-specific inhibitors. Adult worm extracts were able to hydrolyze haemoglobin in solution, although no activity was observed by zymography. This haemoglobinolytic activity was ascribed to aspartic proteases following its effective inhibition by pepstatin, which also inhibited the haemoglobinolytic activity of L1 and L3 extracts. The characterization of protease expression throughout the A. costaricensis life cycle may reveal key factors influencing the process of parasitic infection and thus foster our understanding of the disease pathogenesis.

Asunto(s)

Angiostrongylus/enzimología , Proteolisis , Angiostrongylus/clasificación , Animales , Heces/parasitología , Femenino , Larva/enzimología , Masculino , Sigmodontinae

RESUMEN

Angiostrongylus costaricensis is a nematode that causes abdominal angiostrongyliasis, a widespread human parasitism in Latin America. This study aimed to characterize the protease profiles of different developmental stages of this helminth. First-stage larvae (L1) were obtained from the faeces of infected Sigmodon hispidus rodents and third-stage larvae (L3) were collected from mollusks Biomphalaria glabrata previously infected with L1. Adult worms were recovered from rodent mesenteric arteries. Protein extraction was performed after repeated freeze-thaw cycles followed by maceration of the nematodes in 40 mM Tris base. Proteolysis of gelatin was observed by zymography and found only in the larval stages. In L3, the gelatinolytic activity was effectively inhibited by orthophenanthroline, indicating the involvement of metalloproteases. The mechanistic class of the gelatinases from L1 could not be precisely determined using traditional class-specific inhibitors. Adult worm extracts were able to hydrolyze haemoglobin in solution, although no activity was observed by zymography. This haemoglobinolytic activity was ascribed to aspartic proteases following its effective inhibition by pepstatin, which also inhibited the haemoglobinolytic activity of L1 and L3 extracts. The characterization of protease expression throughout the A. costaricensis life cycle may reveal key factors influencing the process of parasitic infection and thus foster our understanding of the disease pathogenesis.

Asunto(s)

Animales , Femenino , Masculino , Angiostrongylus/enzimología , Proteolisis , Angiostrongylus/clasificación , Heces/parasitología , Larva/enzimología , Sigmodontinae

RESUMEN

This note describes the sudden death of a dog by the rupture of the thoracic aorta caused by the presence of Angiostrongylus vasorum. A female mongrel canine with a history of weight loss and exhaustion died two hours after clinical examination. At necropsy, performed one hour after death, showed the presence of clotted blood in the thoracic cavity. Haemothorax was diagnosed. The thoracic aorta wall was thin, congested and an abnormal hole in the wall was detected approximately 0.5 cm from the entrance to the diaphragm. From clotted blood collected from the thoracic cavity, 224 first stage larvae (L1) and 15 adults of Angiostrongylus vasorum were recovered alive. Also, from a blood clot found in the aorta, four adult females and 47 L1 larvae were recovered alive. Possibly, this parasite was responsible for the aortic rupture and death of the animal.

Asunto(s)

Aorta Torácica/parasitología , Rotura de la Aorta/veterinaria , Muerte Súbita/veterinaria , Enfermedades de los Perros/parasitología , Infecciones por Strongylida/veterinaria , Angiostrongylus/clasificación , Angiostrongylus/aislamiento & purificación , Animales , Aorta Torácica/patología , Rotura de la Aorta/parasitología , Autopsia/veterinaria , Muerte Súbita/etiología , Diagnóstico Diferencial , Enfermedades de los Perros/diagnóstico , Enfermedades de los Perros/patología , Perros , Resultado Fatal , Heces/parasitología , Femenino , Larva , Masculino , Infecciones por Strongylida/complicaciones , Infecciones por Strongylida/diagnóstico

RESUMEN

Achatina fulica, também conhecido como caramujo africano, é um molusco terrestre que pode atuar como hospedeiro intermediário de vários helmintos, entre eles alguns com importância médica e veterinária como Angiostrongylus cantonensis e Angiostrongylus costaricensis, nematódeos responsáveis pela meningoencefalite eosinofílica e pela angiostrongilose abdominal, respectivamente. Este estudo objetivou conhecer a distribuição deste molusco no estado de Goiás e pesquisar a ocorrência de larvas de nematódeos de interesse parasitológico. Detectado, inicialmente, em 2003 no município de Morrinhos, A. fulica teve sua distribuição geográfica ampliada e encontra-se atualmente presente em 39,5por cento, dos municípios de Goiás. A pesquisa da helmintofauna,realizada pela técnica de digestão artificial das amostras obtidas em Caldas Novas, Morrinhos e BelaVista de Goiás, resultou no encontro de larvas de Aelurostrongylus abstrusus (prevalência de 35por cento), Rhabditis sp. (47,5por cento), Strongyluris sp. (15por cento) e de outros metastrongilídeos (2,5por cento). Este estudo ampliou o conhecimento da distribuição geográfica de A. fulica em Goiás e reforçou a participação deste molusco em ciclos biológicos de helmintos, indicando a necessidade de controle e vigilância epidemiológica em áreas urbanas com grande densidade deste molusco em razão da facilidade de contato com as populações humanas e de animais domésticos, o que propicia a transmissão de zoonoses.

Asunto(s)

Humanos , Animales , Angiostrongylus/clasificación , Caracoles , Metastrongyloidea/clasificación , Nematodos , Monitoreo Epidemiológico , Brasil/epidemiología , Demografía

RESUMEN

Angiostrongylus lenzii n. sp. (Nematoda: Metastrongyloidea) is described and illustrated from the pulmonary artery of the wild rodent Akodon montensis Thomas, 1913, collected in the municipality of Teresopólis, Rio de Janeiro State, Brazil. It represents the 17th species of the genus and the 2nd in South America as parasites in rodents. This new species is the most similar morphologically to Angiostrongylus vasorum, Angiostrongylus gubernaculatus, Angiostrongylus schmidti, and Angiostrongylus morerai. It can be distinguished from them by the morphology of the caudal bursa, ventral rays 2 and 3 with conspicuous knobs, differences in width and length of lateral and dorsal rays, presence of rays 8, and length of spicules.

Asunto(s)

Angiostrongylus/clasificación , Enfermedades de los Roedores/parasitología , Sigmodontinae/parasitología , Infecciones por Strongylida/veterinaria , Angiostrongylus/anatomía & histología , Angiostrongylus/aislamiento & purificación , Animales , Brasil/epidemiología , Femenino , Masculino , Prevalencia , Arteria Pulmonar/parasitología , Enfermedades de los Roedores/epidemiología , Infecciones por Strongylida/epidemiología , Infecciones por Strongylida/parasitología

RESUMEN

Angiostrongylus vasorum is a nematode parasite of sylvan and domestic species of the family Canidae. It has a broad but patchy distribution worldwide, and there is evidence for geographical spread and increasing incidence of infection in recent years. While historically Angiostrongylus-like nematodes identified in dogs and foxes have been described as A. vasorum in Europe and Angiocaulus raillieti in South America, more recent taxonomic revision has amalgamated these into a single species, A. vasorum. Here we report, for the first time, the molecular characterization of isolates of A. vasorum from Germany, Portugal, Denmark and the United Kingdom on the basis of the mitochondrial COI gene and the second ribosomal internal transcribed spacer. When compared with isolates from Brazil, sequence analysis revealed 2 distinct genotypes. Estimated rates of evolution based on COI sequences for both nematode and host are consistent with the hypothesis that the presence of A. vasorum in South America is a result of an ancient evolutionary event. Angiostrongylus vasorum in South America potentially represents a separate species to that observed in Europe.

Asunto(s)

Angiostrongylus/clasificación , Canidae/parasitología , Filogenia , Angiostrongylus/genética , Animales , Secuencia de Bases , ADN Espaciador Ribosómico/genética , Complejo IV de Transporte de Electrones/genética , Europa (Continente) , Variación Genética , Datos de Secuencia Molecular , Alineación de Secuencia , América del Sur

RESUMEN

Angiostrongylus morerai n. sp. (Nematoda: Angiostrongylidae) is described from the pulmonary arteries of Azara's grass mouse Akodon azarae (Rodentia: Cricetidae) in Argentina. It is distinguished from its congeners principally by the morphology of the dorsal ray, which is as long, or longer, than the externodorsals and has 2 long branches; the spicule lengths are also greater (400-465 microm). This is the first record of a metastrongyloid from sigmodontine rodents in Argentina.

Asunto(s)

Angiostrongylus/clasificación , Arteria Pulmonar/parasitología , Enfermedades de los Roedores/parasitología , Sigmodontinae/parasitología , Infecciones por Strongylida/veterinaria , Angiostrongylus/anatomía & histología , Angiostrongylus/ultraestructura , Animales , Argentina , Femenino , Masculino , Microscopía Electrónica de Rastreo/veterinaria , Infecciones por Strongylida/parasitología

RESUMEN

In life cycle of Angiostrongylus costaricensis, veronicellidae mollusks participate as the invertebrate host while rodents as the main vertebrate host. The current work shows a sequential larval development of A. costaricensis in Sarasinula marginata, individually killed and digested from day 1 to 43, post infection. Some larvae, recovered from sedimentation, were submitted to selective staining after paraffin embedded or inclusion in JB-4 to study inner structures. As control, four slugs were used, two killed at the beginning of infection and the others at the end of the experiment. At day 2 post infection, larvae were motionless and thick, presenting initial retention of granules. At day 4, L2 were detected, persisting until 43 days post infection. Larvae L2 displayed a large amount of granules rich in lipids and carbohydrates through its overall body, with more accumulation at the medial third corresponding to the esophagus-intestine transition site. Lipid granules, the main energetic source, were located at the basal and apical regions of intestinal cells. Both L1 and L3 presented bilateral alae, which is also common in other nematodes. Transition forms between L2 to L3 molts were also observed.

Asunto(s)

Angiostrongylus/fisiología , Interacciones Huésped-Parásitos , Moluscos/parasitología , Angiostrongylus/clasificación , Angiostrongylus/crecimiento & desarrollo , Animales , Larva/química , Larva/crecimiento & desarrollo , Estadios del Ciclo de Vida , Lípidos/análisis , Moluscos/ultraestructura , Muda

RESUMEN

Angiostrongylus cantonensis, A. costaricensis, and A. vasorum are etiologic agents of human parasitic diseases. Their identification, at present, is only possible by examining the adult worm after a 40-day period following infection of vertebrate hosts with the third-stage larvae. In order to obtain a diagnostic tool to differentiate larvae and adult worm from the three referred species, polymerase chain reaction-restriction fragment length polymorphism was carried out. The rDNA second internal transcribed spacer (ITS2) and mtDNA cytochrome oxidase I regions were amplified, followed by digestion of fragments with the restriction enzymes RsaI, HapII, AluI, HaeIII, DdeI and ClaI. The enzymes RsaI and ClaI exhibited the most discriminating profiles for the differentiation of the regions COI of mtDNA and ITS2 of rDNA respectively. The methodology using such regions proved to be efficient for the specific differentiation of the three species of Angiostrongylus under study.

Asunto(s)

Angiostrongylus/genética , Angiostrongylus/clasificación , Angiostrongylus/enzimología , Animales , Enzimas de Restricción del ADN/análisis , ADN Mitocondrial/análisis , Marcadores Genéticos , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , ARN Ribosómico/análisis , Especificidad de la Especie

Asunto(s)

Angiostrongylus/clasificación , Infecciones por Strongylida/historia , Animales , Costa Rica , Historia del Siglo XX , Humanos , Infecciones por Strongylida/parasitología , Terminología como Asunto