143 research outputs found

    Maternal antibodies postpone hantavirus infection and enhance individual breeding success

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    The transfer of maternal antibodies from mother to progeny is a well-known phenomenon in avian and mammalian species. Optimally, they protect the newborn against the pathogens in the environment. The effect of maternal antibodies on microparasite transmission dynamics may have important consequences for both the fitness of the host and the epizootic processes of the pathogens. However, there is a scarcity of studies examining these effects in free-living wild species. We studied the influence of maternal antibodies against the zoonotic Puumala hantavirus (PUUV) on the fitness of bank voles (Clethrionomys glareolus) and on PUUV transmission by exposing young maternal antibody-positive (MatAb+) and negative (MatAb−) bank voles (n=160) to PUUV in experimental populations. PUUV-specific maternal antibodies delayed the timing of infection. Females were more susceptible to PUUV infection than males. Interestingly, both the females and the males with maternal antibodies matured earlier than the other individuals in the population. Our results highlight the significance of maternal antibodies in the transmission of a pathogen and in the breeding success of the carriers

    Can number and size of offspring increase simultaneously? - a central life-history trade-off reconsidered

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    Background: To maximize their fitness, parents are assumed to allocate their resources optimally between number and size of offspring. Although this fundamental life-history trade-off has been subject to long standing interest, its genetic basis, especially in wild mammals, still remains unresolved. One important reason for this problem is that a large multigenerational pedigree is required to conduct a reliable analysis of this trade-off. Results: We used the REML-animal model to estimate genetic parameters for litter size and individual birth size for a common Palearctic small mammal, the bank vole (Myodes glareolus). Even though a phenotypic trade-off between offspring number and size was evident, it was not explained by a genetic trade-off, but rather by negative correlations in permanent and temporary environmental effects. In fact, even positive genetic correlations were estimated between direct genetic effects for offspring number and size indicating that genetic variation in these two traits is not necessarily antagonistic in mammals. Conclusions: Our results have notable implications for the study of the life-history trade-off between offspring number and size in mammals. The estimated genetic correlations suggest that evolution of offspring number and size in polytocous mammals is not constrained by the trade-off caused by antagonistic selection responses per se, but rather by the opposing correlative selection responses in direct and maternal genetic effects for birth size.peerReviewe

    The WMO SPICE snow-on-ground intercomparison: an overview of sensor assessment and recommendations on best practices

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    Comunicación presentada en: TECO-2016 (Technical Conference on Meteorological and Environmental Instruments and Methods of Observation) celebrada en Madrid, del 27 al 30 de septiembre de 2016.One of the objectives of the WMO Solid Precipitation Intercomparison Experiment (SPICE) was to assess the performance and capabilities of automated sensors for measuring snow on the ground (SoG), including sensors that measure snow depth and snow water equivalent (SWE). The intercomparison focused on five snow depth sensors (models SHM30, SL300, SR50A, FLS-CH 10 and USH-8) and two SWE sensors (models CS725 and SSG1000) over two winter seasons (2013/2014 and 2014/2015). A brief discussion of the measurement reference(s) and an example of the intercomparisons are included. Generally, each of the sensors under test operated according to the manufacturer’s specifications and compared well with the site references, exhibiting high correlations with both the manual and automated reference measurements. The use of natural and artificial surface targets under snow depth sensors were examined in the context of providing a stable and representative surface for snow depth measurements. An assessment of sensor derived measurement quality and sensor return signal strength, where available as an output option, were analysed to help explain measurement outliers and sources of uncertainty with the goal of improving data quality and maximizing the sensor capabilities. Finally, where possible, relationships are established between the gauge measurement of solid precipitation and the measurement of snow on the ground. This paper will provide a brief summary of these results with more detail included in the WMO SPICE Final Report

    Systemic blockade of ACVR2B ligands prevents chemotherapy-induced muscle wasting by restoring muscle protein synthesis without affecting oxidative capacity or atrogenes

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    Doxorubicin is a widely used and effective chemotherapy drug. However, cardiac and skeletal muscle toxicity of doxorubicin limits its use. Inhibiting myostatin/activin signalling can prevent muscle atrophy, but its effects in chemotherapy-induced muscle wasting are unknown. In the present study we investigated the effects of doxorubicin administration alone or combined with activin receptor ligand pathway blockade by soluble activin receptor IIB (sACVR2B-Fc). Doxorubicin administration decreased body mass, muscle size and bone mineral density/content in mice. However, these effects were prevented by sACVR2B-Fc administration. Unlike in many other wasting situations, doxorubicin induced muscle atrophy without markedly increasing typical atrogenes or protein degradation pathways. Instead, doxorubicin decreased muscle protein synthesis which was completely restored by sACVR2B-Fc. Doxorubicin administration also resulted in impaired running performance without effects on skeletal muscle mitochondrial capacity/function or capillary density. Running performance and mitochondrial function were unaltered by sACVR2B-Fc administration. Tumour experiment using Lewis lung carcinoma cells demonstrated that sACVR2B-Fc decreased the cachectic effects of chemotherapy without affecting tumour growth. These results demonstrate that blocking ACVR2B signalling may be a promising strategy to counteract chemotherapy-induced muscle wasting without damage to skeletal muscle oxidative capacity or cancer treatment.Peer reviewe

    CHEK2 c.1100delC mutation is associated with an increased risk for male breast cancer in Finnish patient population

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    Background: Several susceptibility genes have been established for female breast cancer, of which mutations in BRCA1 and especially in BRCA2 are also known risk factors for male breast cancer (MBC). The role of other breast cancer genes in MBC is less well understood.Methods: In this study, we have genotyped 68 MBC patients for the known breast or ovarian cancer associated mutations in the Finnish population in CHEK2, PALB2, RAD51C, RAD51D, and FANCM genes.Results: CHEK2 c.1100delC mutation was found in 4 patients (5.9%), which is significantly more frequent than in the control population (OR: 4.47, 95% CI 1.51-13.18, p = 0.019). Four CHEK2 I157T variants were also detected, but the frequency did not significantly differ from population controls (p = 0.781). No RAD51C, RAD51D, PALB2, or FANCM mutations were found.Conclusions: These data suggest that the CHEK2 c.1100delC mutation is associated with an increased risk for MBC in the Finnish population

    Analysis of single-Alter-shielded and unshielded measurements of mixed and solid precipitation from WMO-SPICE

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    Precipitation measurements were combined from eight separate precipitation testbeds to create multi-site transfer functions for the correction of unshielded and single-Alter-shielded precipitation gauge measurements. Site-specific errors and more universally applicable corrections were created from these WMO-SPICE measurements. The importance and magnitude of such wind speed corrections were demonstrated.This research was funded by the Korean Ministry of Land, Infrastructure and Transport through a grant (16AWMP-B079625-03) from the Water Management Research Program
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