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Background

Mallard ducks and other waterfowl represent the most important reservoirs of low pathogenic avian influenza viruses (LPAIV). In addition, mallards are the most abundant duck species in Eurasia that migrate over long distances. Despite extended wild bird monitoring studies over the past decade in many Eurasian countries and investigating hundreds of thousands of wild bird samples, no mallard duck was found to be positive for avian influenza virus of subtype H16 in faecal, cloacal or oropharyngeal samples. Just three cases of H16 infections in Anseriformes species were described worldwide. In contrast, H16 viruses have been repeatedly isolated from birds of the Laridae family.

Objective

Here, we tested the hypothesis that mallards are less permissive to infection with H16 viruses.

Methods

Groups of mallard ducks of different age were inoculated via the oculo-nasal-oral route with different infectious doses of an H16N3 AIV.

Results

The ducks did not show any clinical symptoms, and no virus shedding was evident from cloacal and respiratory routes after experimental infection as shown by negative RT-qPCR results. In addition, all serum samples taken on days 8, 21 and 24 post-inoculation were negative by competitive NP-ELISA.

Conclusions

This study provided evidence that mallards are resistant to infection with H16N3 LPAIV.  相似文献   
74.
In Belgium, and in other OECD countries, there is a growing awareness about the importance of informal home care for the elderly’s well-being. Informal care is considered as an intrinsically valuable social phenomenon. Public authorities in Belgium have been advocating an active policy of support for informal carers. In 2007, an extensive survey was carried out in the Belgian municipality of Kruibeke in order to establish a better picture of the various needs of the elderly in their home situation, but also to better understand the way in which informal care is provided and perceived by care receivers and care givers. The study points to the need for support for the difficult burden of informal care and highlights the need for a coordinated and integrated approach to elderly care.  相似文献   
75.
The Kv2.1 voltage‐gated K+ channel is widely expressed throughout mammalian brain, where it contributes to dynamic activity‐dependent regulation of intrinsic neuronal excitability. Here we show that somatic plasma membrane Kv2.1 clusters are juxtaposed to clusters of intracellular ryanodine receptor (RyR) Ca2+‐release channels in mouse brain neurons, most prominently in medium spiny neurons (MSNs) of the striatum. Electron microscopy–immunogold labeling shows that in MSNs, plasma membrane Kv2.1 clusters are adjacent to subsurface cisternae, placing Kv2.1 in close proximity to sites of RyR‐mediated Ca2+ release. Immunofluorescence labeling in transgenic mice expressing green fluorescent protein in specific MSN populations reveals the most prominent juxtaposed Kv2.1:RyR clusters in indirect pathway MSNs. Kv2.1 in both direct and indirect pathway MSNs exhibits markedly lower levels of labeling with phosphospecific antibodies directed against the S453, S563, and S603 phosphorylation site compared with levels observed in neocortical neurons, although labeling for Kv2.1 phosphorylation at S563 was significantly lower in indirect pathway MSNs compared with those in the direct pathway. Finally, acute stimulation of RyRs in heterologous cells causes a rapid hyperpolarizing shift in the voltage dependence of activation of Kv2.1, typical of Ca2+/calcineurin‐dependent Kv2.1 dephosphorylation. Together, these studies reveal that striatal MSNs are distinct in their expression of clustered Kv2.1 at plasma membrane sites juxtaposed to intracellular RyRs, as well as in Kv2.1 phosphorylation state. Differences in Kv2.1 expression and phosphorylation between MSNs in direct and indirect pathways provide a cell‐ and circuit‐specific mechanism for coupling intracellular Ca2+ release to phosphorylation‐dependent regulation of Kv2.1 to dynamically impact intrinsic excitability. J. Comp. Neurol. 522:3555–3574, 2014. © 2014 Wiley Periodicals, Inc.  相似文献   
76.

Aims

Only limited data exist about the role of point of care CYP2C19 testing in the acute setting in the early phase of acute coronary syndromes (ACS). Therefore, the present study was designed to investigate the impact of CYP2C19 loss-of–function point-of-care (POC) genotyping in patients presenting with acute coronary syndromes (ACS) and treated with dual antiplatelet therapy in the emergency setting.

Methods and Results

137 subjects with ACS scheduled for percutaneous coronary intervention were consecutively enrolled. Pre- and on-treatment platelet aggregation was assessed by multiple electrode aggregometry (MEA) after stimulation with adenosine diphosphate (ADP). Patients were loaded according to current guideline adherent indications and contraindications for use of P2Y12 inhibitors in ACS. POC genotyping for CYP2C19*2 was performed in the emergency room after obtaining a buccal swab using the Spartan RX CYP2C19 system and obtaining patient’s informed consent. Prasugrel and ticagrelor treated patients had significantly lower PR compared to clopidogrel-treated patients. The benefits of prasugrel and ticagrelor compared to clopidogrel treated patients in terms of platelet inhibition were more pronounced in CYP2C19*2 carriers. Non-carriers showed similar inhibition regardless of particular P2Y12 inhibitor treatment. Statistical analyses adjusting for factors associated with response (e.g. smoking) revealed that CYP2C19*2 allele carrier status and loading with different type of P2Y12 receptor blockers were significant predictors of on-treatment platelet reactivity in the early phase of ACS.

Conclusion

The results of this pilot study of treatment of patients in the early phase of ACS indicate that CYP2C19*2 POC genotyping might help to identify patients at risk with poor response to clopidogrel treatment, thereby benefiting from reloading and switching to alternative P2Y12 receptor inhibition.  相似文献   
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Commensal microbiota plays a key role in the health and disease of the host. The innate immune system comprises an essential functional component of the intestinal mucosal barrier, maintaining hyporesponsiveness to omnipresent harmless commensals in the lumen, but rapidly recognizing and combating invading bacteria through diverse antimicrobial mechanisms. Interactions between commensals and innate immune cells are constant, multidimensional and entirely context-dependent. Environment, genetics and host defense differentially modulate commensal-innate immune effects and functions in the intestinal mucosa. In IBD, dysbiosis, mucus layer disruption, impairment in bacterial clearance, intestinal epithelial cell barrier dysfunction and/or immune cell deregulation may lead to commensal-innate immune miscommunication, which critically drives mucosal inflammation and associated cancer.  相似文献   
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