231 research outputs found

    Proposal of an iELISA for Mycoplasma bovis diagnosis in dairy cattle and associated risk factors.

    Get PDF
    Mycoplasma bovis is a highly contagious agent associated with several pathologies in cattle. The detection of reactive antibodies to M. bovis by Indirect Enzyme-Linked Immunosorbent Assay (iELISA) identifies if there was an exposure to the microorganism. The current study aimed to optimize an iELISA from M. bovis total cell antigen, applying it to bovine serum samples, and to evaluate risk factors. Serum samples were obtained from 400 cows from 17 herds from Southeast Brazil. In the optimization of iELISA, the following was established: 2 ?g/mL of antigen, sera dilution 1:300, and conjugate dilution 1:15000. The frequency was 62.3% (249/400) of reactive animals and 100% (17/17) of reactive herds. Risk factors were: herds with more than 100 animals (OR= 3.1; CI= 95%); Holstein breed (OR= 72.5; CI= 95%); cows (OR= 29.7; CI= 95%); intensive breeding system (OR= 3.3; CI= 95%); associated small ruminant production (OR= 4.4; CI= 95%); milk production above 500L (OR= 2.9; CI= 95%); no quarantine (OR= 1.5; CI= 95%); mechanical milking (OR= 5.5; CI= 95%) and cases of mastitis (OR=5.5; CI= 95%). The proposed iELISA was able to detect antibodies reactive to M. bovis in bovine serum. Knowledge of these risk factors can assist in the implementation of prophylactic measures

    Biodiversity conservation: history, protected areas and hotspots

    Get PDF
    Angola is a large country of great physiographic, climatic and habitat diversity, with a corresponding richness in animal and plant species. Legally protected areas (National Parks and Game Reserves) were established from the 1930s and occupied 6% of the country’s terrestrial area at the time of independence in 1975. As a consequence of an extended war, the Protected Areas were exposed to serious neglect, poaching and land invasions. Many habitats of biogeographic importance, and many rare and endemic species came under threat. The recently strengthened administration gives cause for optimism that a new era for biodiversity conservation is at hand. The Protected Areas system was greatly expanded in 2011, and increasing resources are being made available towards achieving management effectivenessinfo:eu-repo/semantics/publishedVersio

    Relative impact of key sources of systematic noise in Affymetrix and Illumina gene-expression microarray experiments

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Systematic processing noise, which includes batch effects, is very common in microarray experiments but is often ignored despite its potential to confound or compromise experimental results. Compromised results are most likely when re-analysing or integrating datasets from public repositories due to the different conditions under which each dataset is generated. To better understand the relative noise-contributions of various factors in experimental-design, we assessed several Illumina and Affymetrix datasets for technical variation between replicate hybridisations of Universal Human Reference (UHRR) and individual or pooled breast-tumour RNA.</p> <p>Results</p> <p>A varying degree of systematic noise was observed in each of the datasets, however in all cases the relative amount of variation between standard control RNA replicates was found to be greatest at earlier points in the sample-preparation workflow. For example, 40.6% of the total variation in reported expressions were attributed to replicate extractions, compared to 13.9% due to amplification/labelling and 10.8% between replicate hybridisations. Deliberate probe-wise batch-correction methods were effective in reducing the magnitude of this variation, although the level of improvement was dependent on the sources of noise included in the model. Systematic noise introduced at the chip, run, and experiment levels of a combined Illumina dataset were found to be highly dependant upon the experimental design. Both UHRR and pools of RNA, which were derived from the samples of interest, modelled technical variation well although the pools were significantly better correlated (4% average improvement) and better emulated the effects of systematic noise, over all probes, than the UHRRs. The effect of this noise was not uniform over all probes, with low GC-content probes found to be more vulnerable to batch variation than probes with a higher GC-content.</p> <p>Conclusions</p> <p>The magnitude of systematic processing noise in a microarray experiment is variable across probes and experiments, however it is generally the case that procedures earlier in the sample-preparation workflow are liable to introduce the most noise. Careful experimental design is important to protect against noise, detailed meta-data should always be provided, and diagnostic procedures should be routinely performed prior to downstream analyses for the detection of bias in microarray studies.</p

    Afasia y depresión post-ictus: una relación predictiva

    Get PDF
    Introducción/objetivos: La depresión se ha mostrado como la complicación psiquiátrica postictus más común, y la que se asocia con un pronóstico peor. Todavía existe incerteza en cuanto a su etiología y factores de riesgo. Algunos factores son reconocidos: gravedad del ictus, grado de discapacidad y déficit cognitivo. Por ello, es urgente definir nuevos factores que faciliten un diagnóstico temprano, lo cual puede disminuir los efectos negativos sobre el proceso de rehabilitación. Objetivos: Determinar la incidencia de la depresión post-ictus (DPI) y estudiar las variables descritas en la literatura como posibles factores predictores de la DPI: sexo, edad, tipo de ictus, lateralidad, territorio vascular y presencia de afasia. Material y métodos: Estudio longitudinal retrospectivo incluyendo a todos los pacientes admitidos en una planta de Medicina Física y Rehabilitación con el diagnóstico de ictus de novo durante dos a˜nos. Inicialmente se incluyeron 144 pacientes. Los criterios de exclusión fueron «ictus previo», «enfermedad psiquiátrica previa con alteración del humor» y «medicación antidepresiva en el momento del ictus». La n final fue de 111 pacientes. Resultados: La incidencia de DPI fue de 38,7%. La presencia de afasia se mostró asociada significativamente con la depresión (p = 0,05). No hubo relación con el tipo de afasia. Los otros predictores analizados no mostraron correlación estadísticamente significativa. Conclusiones: Este estudio establece la afasia como un factor predictivo de DPI. La elevada incidencia de la DPI en esta población concuerda con los estudios existentes. Adicionalmente se necesitan más estudios, no solo para aumentar el conocimiento de los factores de riesgo para la DPI, sino también para mejorar los resultados de los programas de rehabilitación

    Polycyclic aromatic hydrocarbons bioaccessibility in seafood: Culinary practices effects on dietary exposure

    Get PDF
    This work aimed to determine the effect of culinary practices on the contamination level and bioaccessibility of polycyclic aromatic hydrocarbons (PAHs) in seafood. The selected farmed seafood species (marine shrimp, clams and seaweed) were commercially available in Portugal. The mean concentrations of PAHs varied between 0.23 and 51.8 µg kg-1, with the lowest value being observed in raw shrimp and the highest in dried seaweed. The number of compounds detected in seaweed and clams (naphthalene, acenaphthene, fluorene, phenanthrene, benzo(b)fluoranthene and benzo(j)fluoranthene) were higher than in shrimp (fluorene and pyrene). Among the PAHs measured, fluorene was the predominant one. There was a significant interaction effect between species and culinary treatment (p < 0.05), thus boiled and dried seaweed samples presented the lowest and the highest levels of fluorene (0.13 and 1.8 µg kg-1), respectively. The daily intake of PAHs decreased with bioaccessibility, varying from 22% for benzo(k)fluoranthene (in raw clam) to 84% for phenanthrene (in steamed clam). According to the potency equivalent concentrations, screening values and bioaccessibility of PAHs, the consumption of marine shrimp, clam and seaweed is considered as safe for consumers.This work received financial support from European (FEDER funds through COMPETE) and Portuguese funds (Fundação para a Ciência e Tecnologia Project UID/QUI/50006/2013). The Portuguese Foundation for Science and Technology supported the Ph.D. Grant of ALM (SFRH/BD/103569/2014) as well as the post-doc Grant of P.A. (SFRH/BPD/100728/2014) and the IF2014 contract of AM.info:eu-repo/semantics/publishedVersio
    corecore