ABSTRACT
Some Lymnaeid snails are intermediate hosts of the liver fluke Fasciola hepatica, the causal agent of fasciolosis, a zoonotic parasitic disease. Human and livestock fasciolosis has been reported in a highland community located in the Chimborazo Province of the Ecuadorian Andes. However, no previous study has been carried out to identify which snail species act as intermediate host/s of F. hepatica. This study first aimed to identify the intermediate snail species and secondly to determine the prevalence of natural infection with F. hepatica in 230 lymnaeid snails sampled from irrigation and drainage canals in this area. The first objective entailed observations of shell morphology and internal organs as well as sequencing of the cytochrome oxidase subunit 1 (COI) gene. For the second objective, we used classic parasitological methods (observation of rediae and cercarial emission) and PCR amplification specie-specific to F. hepatica. COI haplotype networks were built to elucidate phylogeographic relationships between the snail populations from this highland community with other American and worldwide populations. We identified two lymnaeid Galba cousini and Galba schirazensis and found high infection rates of F. hepatica in G. cousini, but these differed according to the method used, with PCR showing a higher rate (61 ± 20%) compared to rediae observation (29 ± 17%). F. hepatica in G. schirazensis was identified only by DNA amplification. G. cousini populations were genetically structured by geographic distance whereas G. schirazensis populations showed very low genetic diversity. The higher abundance and infection rate of G. cousini compared to G. schirazensis suggests that the former is likely the specie responsible for F. hepatica transmission in this region.
Subject(s)
Fasciola hepatica/isolation & purification , Snails/parasitology , Animals , Disease Vectors , Ecuador , Species SpecificityABSTRACT
BACKGROUND: Performance of migrating birds can be affected by a number of intrinsic and extrinsic factors like morphology, meteorological conditions and migration strategies. We compared travel speeds of four raptor species during their crossing of the Sahara desert. Focusing the analyses on this region allows us to compare different species under equivalent conditions in order to disentangle which factors affect migratory performance. METHODOLOGY/PRINCIPAL FINDING: We tracked raptors using GPS satellite transmitters from Sweden, Spain and Italy, and evaluated their migratory performance at both an hourly and a daily scale. Hourly data (flight speed and altitude for intervals of two hours) were analyzed in relation to time of day, species and season, and daily data (distance between roosting sites) in relation to species, season, day length and tailwind support. CONCLUSIONS/SIGNIFICANCE: Despite a clear variation in morphology, interspecific differences were generally very small, and did only arise in spring, with long-distance migrants (>5000 km: osprey and Western marsh-harrier) being faster than species that migrate shorter distances (Egyptian vulture and short-toed eagle). Our results suggest that the most important factor explaining hourly variation in flight speed is time of day, while at a daily scale, tailwind support is the most important factor explaining variation in daily distance, raising new questions about the consequences of possible future changes in worldwide wind patterns.
Subject(s)
Animal Migration/physiology , Raptors/physiology , Seasons , Africa, Northern , AnimalsABSTRACT
Objetivo: analizar las formas de presentacion, los diferentes abordajes y los resultados quirurgicos de cada malformacion. Metodo: entre diciembre de 1990 y diciembre de 2001 fueron operados en nuestro años (rango 6 dias a 18 años). El debut fue hemorragico en 32, diagnosticadas en el estudio de convulsiones 4; 4 presentaron cefaleas como unica manifestacion previa y 1 fue un hallazgo asintomatico debido a un traumatismo craneoencefalico. Seis pacientes requirieron manejo de su hidrocefalia aguda con ventriculostomia transitoria y 4 necesitaron derivacion permanente. La embolizacion preoperatoria se realizo en 4 pacientes. Veinte pacientes portaban MAV grado I de Spetzler - Martin, 17 grado II y 2 grado III. Dos pacientes de hallazgo intraoperatorio no puedieron ser categorizados. Resultados: La exeresis completa se obtuvo en 40 casos: 2 pacientes con dos procedimientos, uno con tres y un paciente presento "recidiva" de una MAV pericallosa luego de 3 años del control angiografico postoperatorio sin evidencia de malformacion. La aparicion de nuevo deficit postoperatorio se constato en 4 pacientes, no se registraron hemorragias postoperatorias inmediatas ni mortalidad operatoria. El tiempo de seguimiento fue de 6 meses a 10 años (AU)
Subject(s)
Humans , Adult , Intracranial Hemorrhages , Arteriovenous Malformations , Cerebral AngiographyABSTRACT
Objetivo: analizar las formas de presentacion, los diferentes abordajes y los resultados quirurgicos de cada malformacion. Metodo: entre diciembre de 1990 y diciembre de 2001 fueron operados en nuestro años (rango 6 dias a 18 años). El debut fue hemorragico en 32, diagnosticadas en el estudio de convulsiones 4; 4 presentaron cefaleas como unica manifestacion previa y 1 fue un hallazgo asintomatico debido a un traumatismo craneoencefalico. Seis pacientes requirieron manejo de su hidrocefalia aguda con ventriculostomia transitoria y 4 necesitaron derivacion permanente. La embolizacion preoperatoria se realizo en 4 pacientes. Veinte pacientes portaban MAV grado I de Spetzler - Martin, 17 grado II y 2 grado III. Dos pacientes de hallazgo intraoperatorio no puedieron ser categorizados. Resultados: La exeresis completa se obtuvo en 40 casos: 2 pacientes con dos procedimientos, uno con tres y un paciente presento "recidiva" de una MAV pericallosa luego de 3 años del control angiografico postoperatorio sin evidencia de malformacion. La aparicion de nuevo deficit postoperatorio se constato en 4 pacientes, no se registraron hemorragias postoperatorias inmediatas ni mortalidad operatoria. El tiempo de seguimiento fue de 6 meses a 10 años
