52 research outputs found
Field evaluation of the enhanced MM3-COPRO ELISA test for the diagnosis of Fasciola hepatica infection in sheep
Fasciolosis is a severe zoonosis responsible for major economic losses in livestock. The enhanced MM3-COPRO test (eMM3-COPRO) and the commercial version BIO K 201 (Bio-X Diagnostics, Rochefort, Belgium) are widely used as immunodiagnostic tools for the specific detection of coproantigens released by Fasciola during the late prepatent and patent stages of infection. However, performance of the eMM3-COPRO has never been evaluated under field conditions. To address this gap, a large number of ovine faecal samples, collected in a region where fasciolosis is endemic (Galicia, NW Spain), were analyzed. Two groups of sheep flocks were selected according to the Fasciola infection status: ‘Fasciola-free’ and ‘Fasciola-infected’ flocks. ‘Fasciola-free’ flocks were seronegative flocks with no history of fasciolosis detected by either coproscopy or necropsy in the last 5 years. Faecal samples from these sheep were used to calculate a cut-off value for infection (OD = 0.021). The cut-off was calculated using a bootstrap resampling method that enables estimation of the sampling distribution of the statistical parameters without making assumptions about the underlying data distribution. ‘Fasciola-infected’ flocks were characterized by high seroprevalence, a history of fasciolosis and periodical treatment with flukicides. Samples from these flocks were used to estimate the diagnostic accuracy of the eMM3-COPRO relative to coproscopy, which although limited by poor sensitivity is the only reference test available for diagnosing fasciolosis in vivo. To overcome this limitation, all animals classified positive by eMM3-COPRO were treated with triclabendazole and then retested. The eMM3-COPRO displayed higher sensitivity than coproscopy, as it detected coproantigens in all samples with positive coproscopy and in 12% of samples with negative coproscopy. The test also proved highly specific as coproantigens disappeared after the treatment. The eMM3-COPRO was less time consuming than coproscopy, particularly when the procedure involved numerous samples, and showed promise as a tool for monitoring flukicide efficacyS
Transmission of Calicophoron daubneyi and Fasciola hepatica in Galicia (Spain): Temporal follow-up in the intermediate and definitive hosts
Background
Paramphistomosis caused by Calicophoron daubneyi and fasciolosis caused by Fasciola hepatica are common parasitic diseases of livestock animals. Transmission of the diseases depends on the presence of intermediate hosts, i.e. freshwater gastropods such as lymnaeids. We carried out a 2-year-long study of the dynamics of the snail population acting as the intermediate host for these parasites, considering the population structure in terms of size/age and infection status. In addition, we determined the kinetics of trematode egg excretion in grazing cows. Generalized Additive Models (GAMs) were used to analyze the associations between different response variables and snail size, sampling month and weather-related variables.
Results
Of the molluscan species examined, Galba truncatula, Radix peregra, Anisus (Anisus) leucostoma and Pisidium casertanum (n = 2802), only G. truncatula was infected with C. daubneyi or F. hepatica, at prevalence rates of 8.2% and 4.4% respectively. The probability of infection with C. daubneyi or F. hepatica was linearly related to snail size, although in different ways (negative for C. daubneyi and positive for F. hepatica). The total snail population increased in winter, when specimens of all size classes were found. Infected snails were more abundant during spring-autumn. Mature cercariae of both parasites were found in most seasons. In the statistical models, the sampling month accounted for a high percentage (71.9–78.2%) of the observed variability in snail abundance. The inclusion of climatic variables in the models moderately increased the percentage of deviance explained (77.7–91.9%). Excretion of C. daubneyi eggs in cow faeces was always higher than that of F. hepatica eggs.
Conclusions
Particular care should be taken to prevent pastures and the surrounding environment being contaminated with parasite eggs during winter-spring, when the number of snails susceptible to miracidial infections is maximal. This is therefore the optimal time for treating grazing animals. Nevertheless, control of trematodosis based only on chemotherapy is difficult in an area such as the study area, where environmental factors favour the regular appearance of snail populations harbouring mature cercariaeThe present study was financially supported by the Ministerio de Economía y Competitividad (AGL2011-30563-C03-03). The funders did not have any role in the study design, data collection and analyses, decision to publish or preparation of the manuscriptS
Formation of Indanone from an Iridanaphthalene Complex
The first example of evolution of an iridanaphthalene into an indanone through an intermediate indenyl is reported, serving as a good example of starting material to obtain indanones. Two new iridanaphthalenes are obtained by intramolecular C–H activation of a phenyl ring of a carbene ligand in [IrCp*{C(OMe)CHCPh2}(L)]PF6 (L = PPh2Me, PMe3) complexes. It is demonstrated that these iridanaphthalene complexes can undergo a thermal reaction to give indenyl complexes and 3-phenylindanone
Electronic effects of substituents on the stability of the iridanaphthalene compound [IrCp*{=C(OMe)CH=C(o–C6H4)(Ph)}(PMe3)]PF6
How do the substituents on the naphthalene skeleton affect the stability of the iridanaphthalene complex [IrCp*{C(OMe)CHC(
o
-C
6
H
4
)(Ph)}(PMe
3
)]PF
6
?Iridanaphthalene complexes are synthesized from the corresponding methoxy(alkenyl)carbeneiridium compounds. The electronic character of the substituents on the 6-position of the metallanaphthalene ring is crucial from the point of view of the stability of the iridanaphthalene, [IrCp*{C(OMe)CHC(
o
-C
6
H
4
)(Ph)}(PMe
3
)]PF
6
,
vs.
its transformation to the corresponding indanone derivatives. Stability studies of the iridanaphthalene compounds revealed that strong electron donor substituents (–OMe) stabilize the iridanaphthalene, while weak electron donor (–Me) and electron withdrawing (–NO
2
) groups favor the formation of indanone derivatives. Two possible indanone isomers can be obtained in the conversion of the unstable iridanaphthalene complexes and a mechanism for the formation of these isomers is proposed
Nucleophilic Attack in Methoxycarbenes: Heterolytic Cleavage of the Carbon (sp 3 )–Oxygen Bond versus Aminolysis
The iridium methoxycarbene [IrCp*Cl{C(OMe)CHCPh2}(PPh2Me)]PF6 (3) can undergo a clean attack by nucleophiles at least by two different pathways: (1) an unusual nucleophilic attack of primary, secondary, and tertiary amines at the sp3 carbon–oxygen bond, which gives an acyl complex and amine alkylation and (2) a nucleophilic attack of the ammonia at the carbenic carbon, which forms a primary aminocarbene
Endogenous transplacental transmission of Neospora caninum during successive pregnancies across three generations of naturally infected sheep
[EN] Endogenous transplacental transmission, which occurs during pregnancy as the result of reactivation of a latent infection in the dam, is the main mechanism of propagation of Neospora caninum within cattle herds. However, the importance of this propagation mechanism has not yet been evaluated in relation to ovine neosporosis. In this study, involving three generations of ewes naturally infected by N. caninum, we demonstrated that endogenous transplacental transmission may also be highly efficient in the ovine host since transmission of infection occurred in 96.6% of gestations and the congenital infection rate ranged between 66.7 and 93%. Nevertheless, parasite burdens decreased gradually in consecutive generations. Reactivation of latent infections had a strong impact on the pregnancy outcome, with high mortality rates recorded in the offspring of the two first generations of ewes (21.4-46.1%). Histological examination of the brain revealed that all aborted foetuses had characteristic lesions of neosporosis (necrotic glial foci) and a few parasite cysts, whereas most stillborn and newborn lambs that died shortly after birth had non-specific lesions (mild glial foci without necrosis) and parasite cysts were more frequent. Microsatellite analysis revealed scarce genetic variability in the N. caninum population, in accordance with a scenario in which infections were of a single origin and were exclusively maintained by clonal propagation through endogenous transplacental transmissionSIThe present study was supported by the Ministerio de Ciencia, Innovación y Universidades of Spain (INIA project RTA2014-00013
Competiciones de programación. Estímulo y salida laboral para los alumnos
Las competiciones de programación son un estímulo
importante para los alumnos de informática. Durante
los últimos años ha crecido el número de estas competiciones
en su mayoría promovidas por grandes empresas
con el propósito de reclutar alumnos brillantes.
La International Collegiate Programming Contest
es la más antigua de ellas, promovida por la ACM y
patrocinada por IBM. A la final mundial van los mejores
equipos de cada una de las más de 90 competiciones
regionales que tienen lugar por todo el mundo.
La regional en la que pueden participar las universidades
españolas es la Southwestern Europe Regional
Contest (España, Italia, Portugal, Suiza, Francia y Austria).
Esta regional fue organizada por la Escola Tècnica
Superior d’Enginyeria Informàtica de la Universitat
Politècnica de València en su edición de 2012 y lo será
también en 2013.
En este trabajo se presenta la experiencia de planificación
de una regional, tanto a nivel organizativo como
de planteamiento de los problemas para la competición.
Asimismo, se destaca la importancia de este
tipo de competiciones en cuanto al desarrollo de habilidades
y destrezas en los alumnos, pues su dedicación
a solucionar distintos tipos de problemas, combinando
conocimientos de matemáticas con técnicas algorítmicas,
les da una formación adicional que saben apreciar
las grandes empresas. Algunos alumnos de la ETSInf
que han participado en estas competiciones están en
proceso o ya han sido contratados por empresas del
sector como es Google.SUMMARY -- Programming contests are a good stimulus for computer
engineering students. These contests have experienced
an expansion during last years thanks to the interest
of big companies for hiring brilliant students.
The International Collegiate Programming Contest
is the oldest one, promoted by ACM and sponsored by
IBM. The ACM-ICPC World Final takes place every
year, only the best teams can participate, which are selected
from the ones who compete in the more than 90
regional contests celebrated around the world. Spanish
universities can participate in the Southwestern Europe
Regional Contest (Spain, Italy, Portugal, France and
Austria). The 2012 edition of this regional contest took
place in Valencia, organised by the School of Computer
Engineering at the Universitat Politècnica de València.
The 2013 edition will be organised in Valencia as
well.
In this paper it is presented the experience of planning
a regional contest, both from the point of view of
organisation as from posing the problems. Additionally,
it is pointed out the value of this sort of programming
contests as they foster the development of some
abilities and skills in students, because the time they
spend solving problems where the knowledge of mathematical
concepts and of algorithmic techniques is
very important. This fact gives students a special training
very appreciated by big software companies. Some
former students from ETSInf who participated in
international programming contests were hired or are
in process of being hired by Google
Paramphistomosis bovina en Galicia
Las paramphistomosis son infecciones producidas por trematodos de la familia Paramphistomidae Fischoeder, 1901, que incluye diferentes géneros y especies que parasitan el tracto gastrointestinal de rumiantes. Los animales se infectan al ingerir pastos contaminados con metacercarias producidas tras el enquistamiento de las fases larvarias emitidas por moluscos que actúan como hospedadores intermediarios. En Galicia, donde también se han detectado explotaciones con altas prevalencias de infección, se desconocían aspectos básicos sobre la epidemiología de estas parasitosis. En consecuencia, se ha realizado un amplio estudio en el que se han abordado muchos aspectos
Whole genome sequencing of turbot (Scophthalmus maximus; Pleuronectiformes):a fish adapted to demersal life
12 páginas, 5 figuras.-- Antonio Figueras ... et al.-- This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0/), which permits non-commercial re-use, distribution, and reproduction in any medium, provided the original work is properly citedThe turbot is a flatfish (Pleuronectiformes) with increasing commercial value, which has prompted active genomic research aimed at more efficient selection. Here we present the sequence and annotation of the turbot genome, which represents a milestone for both boosting breeding programmes and ascertaining the origin and diversification of flatfish. We compare the turbot genome with model fish genomes to investigate teleost chromosome evolution. We observe a conserved macrosyntenic pattern within Percomorpha and identify large syntenic blocks within the turbot genome related to the teleost genome duplication. We identify gene family expansions and positive selection of genes associated with vision and metabolism of membrane lipids, which suggests adaptation to demersal lifestyle and to cold temperatures, respectively. Our data indicate a quick evolution and diversification of flatfish to adapt to benthic life and provide clues for understanding their controversial origin. Moreover, we investigate the genomic architecture of growth, sex determination and disease resistance, key traits for understanding local adaptation and boosting turbot production, by mapping candidate genes and previously reported quantitative trait loci. The genomic architecture of these productive traits has allowed the identification of candidate genes and enriched pathways that may represent useful information for future marker-assisted selection in turbotThis work was funded by the Spanish Government: projects Consolider
Ingenio: Aquagenomics (CSD2007-00002) and Metagenoma
de la Península Ibérica (CSD2007-00005), Ministerio de Economía
y Competitividad and European Regional Development Funds
(AGL2012-35904), and Ministerio de Economía y Competitividad
(AGL2014-51773 and AGL2014-57065-R); and Local Government
Xunta de Galicia (GRC2014/010). P.P. and D.R. gratefully acknowledge
the Spanish Ministerio de Educación for their FPU fellowships
(AP2010-2408, AP2012-0254). Funding to pay the Open Access publication
charges for this article was provided by the Ministerio de
Economía y Competitividad (AGL2014-51773) and Xunta de Galicia
(GRC2014/010)Peer reviewe
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