626 research outputs found

    Autoimmune neurological conditions associated with Zika virus infection

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    Zika virus (ZIKV) is an emerging flavivirus rapidly spreading throughout the tropical Americas. mosquitoes is the principal way of transmission of the virus to humans. ZIKV can be spread by transplacental, perinatal, and body fluids. ZIKV infection is often asymptomatic and those with symptoms present minor illness after 3 to 12 days of incubation, characterized by a mild and self-limiting disease with low-grade fever, conjunctivitis, widespread pruritic maculopapular rash, arthralgia and myalgia. ZIKV has been linked to a number of central and peripheral nervous system injuries such as Guillain-Barré syndrome (GBS), transverse myelitis (TM), meningoencephalitis, ophthalmological manifestations, and other neurological complications. Nevertheless, mechanisms of host-pathogen neuro-immune interactions remain incompletely elucidated. This review provides a critical discussion about the possible mechanisms underlying the development of autoimmune neurological conditions associated with Zika virus infection

    Seroprevalencia de las infecciones por el virus Diarrea Vírica Bovina en ganado bovino en Andalucía

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    Se ha realizado un estudio seroepidemiológico frente al virus de la Diarrea Vírica Bovina (vDVB) en la cabaña bovina andaluza, utilizando para ello un ELISA indirecto para la detección de anticuerpos frente a una proteína altamente conservada (p80). Después de eliminar los animales vacunados, la encuesta se realizó sobre 4.768 individuos pertenecientes a 227 colectivos no vacunados frente al vDVB, mediante muestreo estadístico para un nivel de confianza del 95 por ciento. La seropositividad obtenida ha sido del 42,3 por ciento de los individuos analizados, mientras que la prevalencia estimada de rebaños seropositivos alcanzó el 70,9 por ciento. La proporción de bovinos persistentemente infectados (IP) encontrada en la muestra (0,063 % de los individuos y 1,32 de los colectivos), ha sido más baja de la esperada en función de la alta seroprevalencia detectada, hecho que demuestra que la supervivencia de estos animales lógicamente está condicionada

    Surveillance of Influenza Viruses in Waterfowl Used As Decoys in Andalusia, Spain

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    A longitudinal study was carried out to determine the seroprevalence of avian influenza viruses (AIVs) in waterfowl used as decoys in Andalusia, southern Spain. A total of 2319 aquatic birds from 193 flocks were analyzed before and after the hunting season 2011–2012. In the first sampling, 403 out of 2319 (18.0%, CI95%: 15.8–19.0) decoys showed antibodies against AIVs by ELISA. The AI seroprevalence was significantly higher in geese (21.0%) than in ducks (11.7%) (P,0.001). Besides, the spatial distribution of AIVs was not homogeneous as significant differences among regions were observed. The prevalence of antibodies against AIVs subtypes H5 and H7 were 1.1% and 0.3%, respectively, using hemagglutination inhibition test (HI). The overall and H5 seroprevalences slightly increased after the hunting period (to 19.2% and 1.4%, respectively), while the H7 seroprevalence remained at the same level (0.3%). The proportion of flocks infected by AIVs was 65.3%, while 11.2% and 4.9% of flocks were positive for H5 and H7, respectively. Viral shedding was not detected in any of the 47 samples positive by both ELISA and HI, tested by RRT-PCR. The individual incidence after the hunting season was 3.4%. The fact that 57 animals seroconverted, 15 of which were confirmed by HI (12 H5 and 3 H7), was indication of contact with AIVs during the hunting period. The results indicate that waterfowl used as decoys are frequently exposed to AIVs and may be potentially useful as sentinels for AIVs monitoring. The seroprevalence detected and the seropositivity against AIVs H5 and H7, suggest that decoys can act as reservoirs of AIVs, which may be of animal and public health concer

    A multiple-trait analysis of ecohydrological acclimatisation in a dryland phreatophytic shrub

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    Water is the main limiting factor for groundwater-dependent ecosystems (GDEs) in drylands. Predicted climate change (precipitation reductions and temperature increases) and anthropogenic activities such as groundwater drawdown jeopardise the functioning of these ecosystems, presenting new challenges for their management. We developed a trait-based analysis to examine the spatiotemporal variability in the ecophysiology of Ziziphus lotus, a long-lived phreatophyte that dominates one of the few terrestrial GDEs of semiarid regions in Europe. We assessed morpho-functional traits and stem water potential along a naturally occurring gradient of depth-to-groundwater (DTGW, 2–25 m) in a coastal aquifer, and throughout the species-growing season. Increasing DTGW and salinity negatively affected photosynthetic and transpiration rates, increasing plant water stress (lower predawn and midday water potential), and positively affected Huber value (sapwood cross-sectional area per leaf area), reducing leaf area and likely, plant hydraulic demand. However, the species showed greater salt-tolerance at shallow depths. Despite groundwater characteristics, higher atmospheric evaporative demand in the study area, which occurred in summer, fostered higher transpiration rates and water stress, and promoted carbon assimilation and water loss more intensively at shallow water tables. This multiple-trait analysis allowed us to identify plant ecophysiological thresholds related to the increase in salinity, but mostly in DTGW (13 m), and in the evaporative demand during the growing season. These findings highlight the existence of tipping points in the functioning of a long-lived phreatophyte in drylands and can contribute to the sustainable management of GDEs in southern Europe, paving the way for further studies on phreatophytic species

    A Mathematical Model to Optimize the Neoadjuvant Chemotherapy Treatment Sequence for Triple-Negative Locally Advanced Breast Cancer

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    Background: Triple-negative locally advanced breast cancer is an aggressive tumor type. Currently, the standard sequence treatment is applied, administering anthracyclines first and then a taxane plus platinum. Clinical studies for all possible treatment combinations are not practical or affordable, but mathematical modeling of the active mitotic cell population is possible. Our study aims to show the regions with the tumor’s most substantial cellular population variation by utilizing all possible values of the parameters () that define the annihilatory drug capacity according to the proposed treatment. Method: A piecewise linear mathematical model was used to analyze the cell population growth by applying four treatments: standard sequences of 21 days (SS21) and 14 days (SS14), administering anthracyclines first, followed by a taxane plus platinum, and inverted sequences of 21 days (IS21) and 14 days (IS14), administering a taxane plus platinum first then anthracyclines. Results: The simulation showed a higher effect of IS14 over SS14 when the rate of drug resistance was larger in the cell population during DNA synthesis (G1 and S) compared to cells in mitosis (G2 and M). However, if the proportion of resistant cells in both populations was equivalent, then treatments did not differ. Conclusions: When resistance is considerable, IS14 is more efficient than SS14, reducing the tumor population to a minimum

    Analysis of the Yield of Radish (Raphanus Sativus L.) Fertilized with Compost Based on Organic Waste from Markets and its Relationship with its Stomatal Density

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    For higher yields in vegetable cultivation, the availability of soil nutrients must be improved. Therefore, the aim of this research was to establish the relationship between stomatal density and the yield of the radish crop fertilized with compost made from organic market waste. A completely randomized block design was used, which consisted of 3 blocks and 5 treatments, which were T1, T2, T3, T4 and T5 with 00, 10, 15, 15, 20 and 25 g compost/plant respectively. The physical characteristics of the plants were evaluated from sowing to harvest and the data obtained were processed by analysis of variance and Duncan's test. Chemical analysis of the compost and soil was carried out, as well as a foliar analysis to determine the nutrient concentration by treatment. The results determined that the treatment (T4) stood out in plant length with 28.96 cm, plant weight with 43.33 g, yield of 10.82 t/ha and bulb diameter of 3.92 cm; likewise, in the concentration of nutrients in the leaves, the treatment (T5) highlighted in N with 5.94%, Ca 4.84%, Mg 1.29%, Zn 64.58 ppm and a stomatal density of 642 stomas/mm2. It is concluded that, at an adequate dose of compost, the concentration of nutrients increases, as well as the stomatal density, resulting in higher yields
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