20 research outputs found

    Validation of a multilocus genotyping scheme for subtyping Cryptosporidium parvum for epidemiological purposes

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    We would like to thank Prof. Giovanni Widmer and Dr. Willie Weir for their helpful advice on data analysis and Dr. Harriet Risby for her assistance with the manuscript formatting and additional laboratory testing. This work was part funded by the European Union Seventh Framework Programme ( [FP7/2007-2013] [FP7/2007-2011] under Grant agreement no: 311846) .Subtyping Cryptosporidium parvum for outbreak investigations or epidemiological surveillance usually relies on DNA sequence analysis of a gene coding for a 60 KDa glycoprotein (gp60). Although gp60 can be useful for allelic discrimination and to help investigate sources and routes of transmission, the presence of common subtypes and recombination during the parasite's sexual life-cycle demand a multilocus-based method for more discriminatory genotyping. While whole genome sequencing would provide the ultimate approach, it is a time consuming and expensive option for faecal parasites such as Cryptosporidium that occur at low density and are difficult to propagate routinely. In this study, we selected and evaluated a panel of previously identified variable-number tandem-repeat (VNTR) markers, to establish a multilocus genotyping scheme based on fragment sizing, appropriate for inter-laboratory surveillance and outbreak investigations. Seven VNTR markers were validated in vitro and demonstrated typeability of 0.85 and discriminatory power of 0.99. The discriminatory power was much greater than the currently used gp60 sequencing (0.74), which identified 26 subtypes, compared to 100 different MLVA profiles within the same sample set. The assay was robust, with repeatable results and reproducibility across three laboratories demonstrating the scheme was suitable for inter-laboratory comparison of C. parvum subtypes. As the majority of genotypes (79%) were unique among epidemiologically unrelated samples, there was efficiency to infer linkage, and epidemiological concordance was observed in historical outbreaks. We propose that the multilocus variable number of tandem repeats analysis scheme is suitable to assist outbreak investigations.European Commission 31184

    Procesamiento de muestras fecales en el estudio de Cryptosporidium sp. mediante PCR

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    The present paper describes a protocol applied to fecal samples of cattle for the isolation and purification of Cryptosporidium sp. oocysts and the possible use of the same ones for genetic studies by means of PCR.El presente trabajo describe un protocolo aplicado a muestras de heces de ganado bovino para el aislamiento y purificación de ooquistes de Cryptosporidium sp. y el eventual uso de los mismos para estudios genéticos mediante PCR

    Hallazgo de Blastocystis sp. en bivalvos del género Donax

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    Although commonly detected in humans, microorganisms identified as Blastocystis have also been isolated from a wide range of animals, such as primates, pigs, cattle, birds, amphibians and, less frequently, rodents and insects. In the present paper, we describe the detection of Blastocystis sp. in bivalve mollusks of the genus Donax from the Peruvian northern coast. This finding extends the host range of this pathogen, opening the possibility of Blastocytis transmission to human beings by marine mollusks.Aunque es detectado generalmente en seres humanos, los microorganismos identificados como Blastocystis han sido aislados de un amplio rango de hospedadores, tales como primates, cerdos, ganado, aves, anfibios y menos frecuentemente roedores e insectos.En el presente trabajo, se describe la detección de Blastocystis sp. en bivalvos del género Donax de la costa norteña peruana. Este hallazgo amplía el espectro de hospedadores para este enteropatógeno y abre la posibilidad de considerar la posible transmisión de Blastocystis en el hombre a partir de moluscos marinos

    Effects of Enteromyxum spp. (Myxozoa) infection in the regulation of intestinal E‐cadherin: Turbot against gilthead sea bream

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    This is the peer reviewed version of the following article: Ronza, P, Estensoro, I, Bermúdez, R, et al. Effects of Enteromyxum spp. (Myxozoa) infection in the regulation of intestinal E‐cadherin: Turbot against gilthead sea bream. J Fish Dis. 2020; 43: 337– 346, which has been published in final form at https://doi.org/10.1111/jfd.13130. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived VersionsEnteromyxoses are relevant diseases for turbot and gilthead sea bream aquaculture. The myxozoan parasites invade the intestinal mucosa, causing a cachectic syndrome associated with intestinal barrier alteration; nonetheless, their pathological impact is different. Turbot infected by Enteromyxum scophthalmi develop more severe intestinal lesions, reaching mortality rates of 100%, whereas in E. leei‐infected gilthead sea bream, the disease progresses slowly, and mortality rates are lower. The mechanisms underlying the different pathogenesis are still unclear. We studied the distribution and expression changes of E‐cadherin, a highly conserved protein of the adherens junctions, in the intestine of both species by immunohistochemistry and quantitative PCR, using the same immunohistochemical protocol and common primers. The regular immunostaining pattern observed in control fish turned into markedly irregular in parasitized turbot, showing an intense immunoreaction at the host–parasite interface. Nevertheless, E‐cadherin gene expression was not significantly modulated in this species. On the contrary, no evident changes in the protein distribution were noticed in gilthead sea bream, whereas a significant gene downregulation occurred in advanced infection. The results contribute to the understanding of the different host–parasite interactions in enteromyxoses. Host and parasite cells appear to establish diverse relationships in these species, which could underlie the different pathological pictureThis work has been funded by the Spanish Ministry of Economy and Competitiveness and the European Regional Development Fund (ERDF) through the projects AGL2015‐67039‐C3‐1‐R, AGL2015‐67039‐C3‐3‐R and AGL‐2013‐48560‐R and by the Horizon 2020 Framework Programme through ParaFishControl Project (634429). I.E. was contracted under APOSTD/2016/037 grant by the “Generalitat Valenciana” and G.P.‐C. under the “Juan de la Cierva” programme, granted by the Spanish Ministry of Science and Innovation (JCI‐2011‐09438)S

    Purification and biochemical characterization of four iron superoxide dismutases in Trypanosoma cruzi

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    Four superoxide dismutase (SOD) activities (SOD I, II, III, and IV) have been characterized in the epimastigote form of Trypanosoma cruzi . The total extract was subjected to two successive ammonium sulphate additions between 35 and 85%, and the resulting fraction was purified using two continuous chromatography processes (ion exchange and filtration). Enzymes were insensitive to cyanide but sensitive to hydrogen peroxide, properties characteristic of iron-containing SODs. The molecular masses of the different SODs were 20 kDa (SOD I), 60 kDa (SOD II), 50 kDa (SOD III) and 25 kDa (SOD IV), whereas the isoelectric points were 6.9, 6.8, 5.2 and 3.8, respectively. Subcellular location and digitonin experiments have shown that these SODs are mainly cytosolic, with small amounts in the low- mass organelles (SOD II and SOD I) and the mitochondrion (SOD III), where these enzymes play an important role in minimizing oxidative damage.Financial support: CGL2006-27889-E/BOS, Ministerio de Ciencia y Tecnología

    Discovery of new variable number tandem repeat loci in multiple Cryptosporidium parvum genomes for the surveillance and investigation of outbreaks of cryptosporidiosis

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    Cryptosporidium parvum is a protozoan parasite causing gastro-intestinal disease (cryptosporidiosis) in humans and animals. The ability to investigate sources of contamination and routes of transmission by characterisation and comparison of isolates in a cost- and time-efficient manner will help surveillance and epidemiological investigations, but as yet there is no standardised multi-locus typing scheme. To systematically identify variable number tandem repeat (VNTR) loci, which have been shown to provide differentiation in moderately conserved species, we interrogated the reference C. parvum Iowa II genome and seven other C. parvum genomes using a tandem repeat finder software. We identified 28 loci that met criteria defined previously for robust typing schemes for inter-laboratory surveillance, that had potential for generating PCR amplicons analysable on most fragment sizing platforms: repeats ≥6 bp, occurring in tandem in a single repeat region, and providing a total amplicon size of <300 bp including 50 bp for the location of the forward and reverse primers. The qualifying loci will be further investigated in vitro for consideration as preferred loci in the development of a robust VNTR scheme

    Protection of Spanish Ibex (Capra pyrenaica) against Bluetongue Virus Serotypes 1 and 8 in a Subclinical Experimental Infection

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    Many wild ruminants such as Spanish ibex (Capra pyrenaica) are susceptible to Bluetongue virus (BTV) infection, which causes disease mainly in domestic sheep and cattle. Outbreaks involving either BTV serotypes 1 (BTV-1) and 8 (BTV-8) are currently challenging Europe. Inclusion of wildlife vaccination among BTV control measures should be considered in certain species. In the present study, four out of fifteen seronegative Spanish ibexes were immunized with a single dose of inactivated vaccine against BTV-1, four against BTV-8 and seven ibexes were non vaccinated controls. Seven ibexes (four vaccinated and three controls) were inoculated with each BTV serotype. Antibody and IFN-gamma responses were evaluated until 28 days after inoculation (dpi). The vaccinated ibexes showed significant (P<0.05) neutralizing antibody levels after vaccination compared to non vaccinated ibexes. The non vaccinated ibexes remained seronegative until challenge and showed neutralizing antibodies from 7 dpi. BTV RNA was detected in the blood of non vaccinated ibexes from 2 to the end of the study (28 dpi) and in target tissue samples obtained at necropsy (8 and 28 dpi). BTV-1 was successfully isolated on cell culture from blood and target tissues of non vaccinated ibexes. Clinical signs were unapparent and no gross lesions were found at necropsy. Our results show for the first time that Spanish ibex is susceptible and asymptomatic to BTV infection and also that a single dose of vaccine prevents viraemia against BTV-1 and BTV-8 replication

    A922 Sequential measurement of 1 hour creatinine clearance (1-CRCL) in critically ill patients at risk of acute kidney injury (AKI)

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