RESUMEN
Cystic echinococcosis (CE), a parasitic disease caused by the cestode Echinococcus granulosus sensu lato (s.l.), is a worldwide zoonotic infection. Although endemic in Chile, information on the molecular characteristics of CE in livestock remains scarce. Therefore we aimed to describe the status of infection with E. granulosus s.l. in cattle from central Chile and also to contribute to the study of the molecular epidemiology of this parasite. According to our results, the prevalence of CE is 18.84% in cattle, similar to previous reports from Chile, suggesting that the prevalence in Santiago Metropolitan area has not changed in the last 30 years. Most of the cysts were found only in lungs (51%), followed by concurrent infection in liver and lungs (30%), and only liver (19%). Molecular characterization of the genetic diversity and population structure of E. granulosus s.l. from cattle in central Chile was performed using a section of the cytochrome c oxidase subunit 1 (cox1) mitochondrial gene. E. granulosus sensu stricto (s.s.) (G1-G3 genotypes) was confirmed by RFLP-PCR to be the dominant species affecting cattle (284 samples/290 samples); we also report for the first time in Chile the presence of E. ortleppi (G5 genotype) (2 samples/61 samples). The Chilean E. granulosus s.s. parsimony network displayed 1 main haplotype. Additional studies using isolates from many locations across Chile and different intermediate hosts will provide more data on the molecular structure of E. granulosus s.s. within this region. Likewise, investigations of the importance of E. ortleppi in human infection in Chile deserve future attention.
Asunto(s)
Enfermedades de los Bovinos/parasitología , Equinococosis/veterinaria , Echinococcus/aislamiento & purificación , Animales , Bovinos , Enfermedades de los Bovinos/epidemiología , Chile/epidemiología , ADN de Helmintos/análisis , Equinococosis/epidemiología , Equinococosis/parasitología , Echinococcus/clasificación , Echinococcus/fisiología , Femenino , Fertilidad , Genes de Helminto , Genes Mitocondriales , Haplotipos , Masculino , Mutación , Especificidad de Órganos , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , Prevalencia , Alineación de SecuenciaRESUMEN
The objective of the research was to determine the percentage of echinococcosis infection in swine, cystic fertility and associated factors. Cross-sectional study. The population was formed by 579 pigs slaughtered in the slaughterhouse of Huancarama. Hydatid cysts were detected by postmortem evaluation. Fertility was determined by measuring the diameter of the cysts and microscopically observing the germinative membrane in search of protoscoleces. The percentage of cystic echinococcosis infection was 76.7% (CI 95%: 73.2-80.3). Pigs older than two years were more likely to have cysts (RP 1.03; CI 95%: 1.0-1.1; (P < 0.01), as well as those coming from the Andahuaylas district (RP 1.2; CI 95%: 1.1-1.4; P < 0.01). Lung cysts showed a lower percentage of infection than hepatic ones. We examined 346 hydatid cysts of 334 pigs, a total fertility of 42.8% was found (CI 95%: 37.4-48.1).
El objetivo de la investigación fue determinar el porcentaje de infección de equinococosis en porcinos, fertilidad quística y factores asociados. Estudio de corte transversal. La población estuvo conformada por 579 porcinos faenados en el matadero de Huancarama. Los quistes hidatídicos fueron detectados mediante evaluación post mórtem. La fertilidad se determinó midiendo el diámetro de los quistes y observando microscópicamente la membrana germinativa en busca de protoescólices. El porcentaje de infección de equinococosis quística fue de 76,7% (IC95%: 73,2-80,3). Los porcinos mayores a dos años tuvieron más oportunidad de presentar quistes (RP 1,03; IC95%:1,0-1,1; p<0,01), al igual que los provenientes del distrito de Andahuaylas (RP 1,2; IC95%: 1,1-1,4; p<0,01). Los quistes pulmonares presentaron menor porcentaje de infección que los hepáticos. Se examinaron 346 quistes hidatídicos de 334 porcinos, se encontró una fertilidad total de 42,8% (IC95%: 37,4-48,1).
Asunto(s)
Equinococosis/veterinaria , Echinococcus/fisiología , Animales , Estudios Transversales , Equinococosis/epidemiología , Equinococosis/parasitología , Femenino , Masculino , Perú/epidemiología , PorcinosRESUMEN
El objetivo de la investigación fue determinar el porcentaje de infección de equinococosis en porcinos, fertilidad quística y factores asociados. Estudio de corte transversal. La población estuvo conformada por 579 porcinos faenados en el matadero de Huancarama. Los quistes hidatídicos fueron detectados mediante evaluación post mórtem. La fertilidad se determinó midiendo el diámetro de los quistes y observando microscópicamente la membrana germinativa en busca de protoescólices. El porcentaje de infección de equinococosis quística fue de 76,7% (IC95%: 73,2-80,3). Los porcinos mayores a dos años tuvieron más oportunidad de presentar quistes (RP 1,03; IC95%:1,0-1,1; p<0,01), al igual que los provenientes del distrito de Andahuaylas (RP 1,2; IC95%: 1,1-1,4; p<0,01). Los quistes pulmonares presentaron menor porcentaje de infección que los hepáticos. Se examinaron 346 quistes hidatídicos de 334 porcinos, se encontró una fertilidad total de 42,8% (IC95%: 37,4-48,1).
The objective of the research was to determine the percentage of echinococcosis infection in swine, cystic fertility and associated factors. Cross-sectional study. The population was formed by 579 pigs slaughtered in the slaughterhouse of Huancarama. Hydatid cysts were detected by postmortem evaluation. Fertility was determined by measuring the diameter of the cysts and microscopically observing the germinative membrane in search of protoscoleces. The percentage of cystic echinococcosis infection was 76.7% (CI 95%: 73.2-80.3). Pigs older than two years were more likely to have cysts (RP 1.03; CI 95%: 1.0-1.1; (P < 0.01), as well as those coming from the Andahuaylas district (RP 1.2; CI 95%: 1.1-1.4; P < 0.01). Lung cysts showed a lower percentage of infection than hepatic ones. We examined 346 hydatid cysts of 334 pigs, a total fertility of 42.8% was found (CI 95%: 37.4-48.1).
Asunto(s)
Animales , Femenino , Masculino , Equinococosis/veterinaria , Echinococcus/fisiología , Perú/epidemiología , Porcinos , Estudios Transversales , Equinococosis/parasitología , Equinococosis/epidemiologíaRESUMEN
The cystic echinococcosis (CE) is an important zoonotic disease caused by the parasite Echinococcus spp. In Brazil, this parasite is present in Rio Grande do Sul (RS) state, border with Argentina and Uruguay, causing several damages to human and animal health. This study aimed to identify Echinococcus spp. in hydatid cysts of swine and evaluate the similarity of the genotypes through the phylogenetic analysis. A total of 3,101,992 swine were slaughtered in the central/northern region of RS/Brazil, during 2008-2012. Five isolates were characterized as hydatid cyst by molecular analysis, based on the mitochondrial gene cytochrome c oxidase subunit I (cox-I). The genotypes E. granulosus sensu stricto (G1) (n=2) and E. canadensis (G7) (n=3) were identified in the hydatid cysts. The swine represents a potential intermediate host for different genotypes of Echinococcus spp., besides it can contribute to the perpetuation of the parasite's life cycle in rural areas.
Asunto(s)
Equinococosis/veterinaria , Echinococcus granulosus/fisiología , Echinococcus/fisiología , Enfermedades de los Porcinos/parasitología , Animales , Brasil , Equinococosis/parasitología , Echinococcus/clasificación , Echinococcus/genética , Echinococcus granulosus/clasificación , Echinococcus granulosus/genética , Complejo IV de Transporte de Electrones/genética , Genotipo , Interacciones Huésped-Parásitos , Datos de Secuencia Molecular , Filogenia , PorcinosRESUMEN
PURPOSE OF REVIEW: Tissue parasites of humans are still prevalent in most regions of the world, and are also seen more frequently in developed countries due to increasing travel patterns. In particular, Echinococcus infections still account for hepatic and pulmonary pathology, cysticercosis is a major cause of seizures and epilepsy, and fascioliasis also causes significant liver pathology. This review summarizes current knowledge on clinical and epidemiologic aspects of zoonotic disease caused by tissue helminths. RECENT FINDINGS: Tissue helminth infections remain as a public health concern. Recent research has provided new insights into clinical disease in humans and improved methods for diagnosis, treatment and control, arising mostly from the application of new techniques for immune and molecular diagnosis, availability of data from controlled trials, and development of new vaccines. Specific antiparasitic therapies are now better characterized, and new control tools are available. SUMMARY: Recent research has provided new diagnostic technologies applicable to diagnosis, treatment and control, but effective interventions to reduce transmission are rarely applied. Despite some progress in their control, these zoonoses continue to be a major public health problem in many regions both in developing countries and in some more developed ones.
Asunto(s)
Cisticercosis , Equinococosis , Fascioliasis , Animales , Cisticercosis/diagnóstico , Cisticercosis/prevención & control , Cisticercosis/terapia , Equinococosis/diagnóstico , Equinococosis/epidemiología , Equinococosis/prevención & control , Equinococosis/terapia , Echinococcus/fisiología , Fasciola/fisiología , Fascioliasis/diagnóstico , Fascioliasis/epidemiología , Fascioliasis/prevención & control , Fascioliasis/terapia , Humanos , Taenia solium/fisiología , ZoonosisRESUMEN
Echinococcus granulosus is a parasitic platyhelminth, which causes cystid hydatid disease, a major zoonosis involving canids as definitive hosts, and both human and herbivorous domestic animals as intermediate hosts. The disease is caused in intermediate hosts by hydatid cysts, formed upon ingestion of E. granulosus eggs excreted by canids. Protoscoleces, the developmental forms of the parasite infective to canids, are formed in the germinal cellular layer of hydatid cysts. We have found that protoscoleces develop from patches of proliferating cells present in the germinal layer of the hydatid cyst, while most of the other cells of the germinal layer are in a resting state. Further, patches of proliferating cells form buds, which elongate and develop a separate population of cycling cells. In these elongated buds, cell differentiation leads to the main structures of the protoscolex. Protein synthesis is very active among cells of early buds and coincides with their proliferating activity. By contrast, protein synthesis presents a much lower activity in the resting cells of the germinal layer surrounding the growing protoscoleces. In elongated buds at different stages of development, protein synthesis is found mainly close to cellular territories in which cell differentiation occurs. In free infective protoscoleces, cells in DNA synthesis are concentrated in the body of the larva while protein synthesis occurs in the entire larva. This is the first description of the regionalization of DNA and protein synthesis in developing stages of E. granulosus.
Asunto(s)
ADN Protozoario/biosíntesis , Equinococosis Pulmonar/parasitología , Echinococcus/fisiología , Proteínas Protozoarias/biosíntesis , Animales , Bovinos , Diferenciación Celular , División Celular , Replicación del ADN , Equinococosis Hepática/parasitología , Echinococcus/aislamiento & purificación , Caballos , Larva/crecimiento & desarrollo , Leucina/metabolismo , Timidina/metabolismoRESUMEN
Hydatidosis (cystic echinococcosis) constitutes a serious public health problem in the Province of Rio Negro, Argentina. In the present work it was intended to evaluate the prevalence of the canine echinococcosis in rural areas of the Province of Rio Negro and studied the reinfection rate in dogs after treatment with Praziquantel during the period 1980-1997. A total of 496 dogs were studied in 18 canine concentrations in order to establish the initial prevalence rate which was 42.3%. From 1980 onward dogs should have been systematically treated with anthelmintic every 2 months in rural areas and every 6 months in urban areas. We estimated that approximately 65% of dogs were treated. To determine the reinfection rate, 476 dogs (1984) and 598 dogs (1996) were studied after anthelmintic treatment during two sequential time periods (0-45; 46-90 days). In both cases treated animals were compared with untreated dogs. Prevalences were 3.5%, 6.7% and 21.3% in 1984 and 0.8%, 4.0% and 10.0% in 1996. For the purpose of surveillance a total number of 21,444 dogs were studied during 18 years. Prevalence of Echinococcus granulosus decreased significantly in the first year from 42.3% to 6.1%.
Asunto(s)
Enfermedades de los Perros/epidemiología , Equinococosis/veterinaria , Animales , Argentina/epidemiología , Enfermedades de los Perros/parasitología , Perros , Equinococosis/epidemiología , Echinococcus/fisiología , Prevalencia , Recurrencia , Estudios Retrospectivos , Salud RuralRESUMEN
We used the PCR-SSCP method followed by sequencing in order to assess the genetic variability of coding and noncoding parts of the genome of Echinococcus granulosus (Cestoda; Taeniidae) and to test whether or not the parasite populations are mainly self-fertilizing. For this, we analysed a sample of 110 E. granulosus metacestode isolates collected from different geographical regions (Southern Brazil, Europe and Australia) and from different intermediate hosts (ovine, bovine, human, macropod, swine and equine). Using appropriate controls, we were able to identify 4 strains in that sample (sheep, cattle, pig and horse strains). The high degree of genetic differentiation between strains, but not within, and the monomorphism found in most loci (EgAg4, EgActII, EgHbx2 and EgAg6-non-coding-EgAgB/1 and EgND1-coding) indicated that they are largely selfed. On the other hand, outcrossing was also shown to occur, since 5 potential hybrid genotypes between cattle and sheep strains were found in populations of Southern Brazil, but absent in other geographical areas. We suggest that both processes are adaptive. The article also reports, for the first time, the occurrence of the E. granulosus cattle strain in South America.
Asunto(s)
Echinococcus/genética , Endogamia , Animales , Bovinos , Echinococcus/fisiología , Variación Genética/genética , Genética de Población , Genotipo , Caballos/parasitología , Reacción en Cadena de la Polimerasa/métodos , Alineación de Secuencia , Ovinos/parasitología , Porcinos/parasitologíaRESUMEN
A 107-pS (symmetrical 150 mM KCl), nonselective cation channel was reconstituted from a microsomal membrane fraction of the larval stage of the tapeworm Echinococcus granulosus. Most of the time, it displayed a high open probability (>>0.95) irrespective of either the applied voltage, Ca2+, Ba2+, or tetraethylammonium concentration. Nevertheless, in contrast with this "leaklike" behavior, less frequently this "all-the-time-open" channel reversibly entered two different kinetic modes. One of them was characterized by lower Po values and some voltage sensitivity (V(1/2) congruent with 129 mV, and an equilibrium constant for channel closing changing e-fold per 63-mV change) the kinetic analysis revealing that it resulted from the appearance of voltage-sensitivity in the mean closed times and a sixfold increase in the equilibrium constant for channel closing at 0 mV. The other mode was characterized by a very fast open-close activity leading to poorly resolved current levels and a Po around 0.6-0.7 which, occasionally and in a voltage-sensitive manner, entered a long-lived nonconducting state. However, the rare nature of these mode-shifting transitions precluded a more detailed analysis of their kinetics. The conductive properties of the channel were not affected by these switches. Model gating alone does not seem to ensure any physiological role of this channel and, instead, some other channel changes must occur if this phenomenon were to be of regulatory importance in vivo. Thus, mode-shifting might constitute an alternative target for channel activity modulation also in tapeworms.
Asunto(s)
Activación del Canal Iónico/fisiología , Animales , Echinococcus/química , Echinococcus/fisiología , Cinética , Membrana Dobles de Lípidos/química , Canales de Potasio/análisis , Canales de Potasio/fisiologíaAsunto(s)
Cisticercosis/epidemiología , Cisticercosis/prevención & control , Equinococosis/epidemiología , Equinococosis/prevención & control , Echinococcus/fisiología , Taenia/fisiología , África Oriental/epidemiología , Animales , China/epidemiología , Cisticercosis/diagnóstico , Cisticercosis/transmisión , Equinococosis/diagnóstico , Equinococosis/transmisión , Equinococosis Pulmonar/diagnóstico , Equinococosis Pulmonar/epidemiología , Equinococosis Pulmonar/prevención & control , Equinococosis Pulmonar/transmisión , Interacciones Huésped-Parásitos , Humanos , Japón/epidemiología , Tamizaje Masivo , Nepal/epidemiología , América del Sur/epidemiología , Reino Unido/epidemiología , Estados Unidos/epidemiología , ZoonosisRESUMEN
Upon microelectrode impalements of the tegument of Echinococcus granulosus protoscoleces incubated in Ringer Krebs solution, electrical potential differences of -49 +/- 1 mV, using procedure I, and -53 +/- 1 mV, using procedure II, were recorded. The changes in the electrical potential difference as well as the structural alterations produced by sodium deoxicholate indicate that the observed potentials are established across the apical membrane of the syncytial tegument. The electrical potential difference is primarily dependent on the K+ gradient across the tegumental membrane: a 10-fold increase in the external K+ causes a 30-mV change in the electrical potential. External Na+ concentration changes also affected the electrical potential difference, but altering the external Cl- has no detectable effect. Amiloride, a very well-known blocker of Na+ epithelia channels, produced a reversible hyperpolarization that reached the maximum response at 10(-3) M. Ouabain, 10(-4) M, caused a depolarization in both fresh and Na-rich protoscoleces, although this depolarization was greater and showed a faster onset under the latter condition. It is concluded that the electrical potential difference of E. granulosus protoscolex is generated at the apical tegumental membrane and that it can be experimentally divided into two main components: One of them depends on ionic gradients and membrane permeabilities in accordance with the electrodiffusion predicted by the Goldman, Hodgkin, and Katz equation, while the other depends on the electrogenicity of an active Na+/K+ transport system.
Asunto(s)
Echinococcus/fisiología , Amilorida/farmacología , Animales , Cloruros/farmacología , Ácido Desoxicólico/farmacología , Relación Dosis-Respuesta a Droga , Echinococcus/efectos de los fármacos , Conductividad Eléctrica , Electrofisiología , Potenciales de la Membrana , Microelectrodos , Ouabaína/farmacología , Potasio/farmacología , Sodio/farmacologíaRESUMEN
En Colombia el huesped intermediario natural de Echinococcus vogeli Rausch y Bernstein, 1972 es la guagua, Cuniculus paca l. (Rodentia : Dasyproctidae). El cestodo larvario se desarrolla en el higado del huesped, donde casi siempre se lo ve parcialmente expuesto bajo la capsula de Glisson. La larva infectiva esta constituida por una vesicula llena de liquido entre subesferica y asimetrica, con mas de 30 mm de diametro, envuelta por una membrana laminada gruesa. Su lumen contiene numerosas cavidades, que a menudo se interconectan, y que se producen por proliferacion endogena de tejido germinal y laminado, dentro del cual se originan a partir de la capa germinal las vesiculas hijas de distribucion irregular. No se observo crecimiento invasivo, por proliferacion exogena, tipica de las infecciones en el hombre. Se describe el desarrollo del cestodo larvario con base en material de guaguas, suplementado mediante la observacion de lesiones iniciales en nutrias experimentalmente infectadas. Miocastor coypus (Molina) (Rodentia : Capromyidae). En el huesped intermediario, que tiene una vida comparativamente larga, se observa el estadio larvario temprano, el maduro (infectivo), y las larvas que sufren degeneracion. Cada uno con una respuesta tisular diferente. Ademas de las diferencias descritas antes sobre tamanos y formas de los ganchos rostelares, se han definido otras caracteristicas..