2,576 research outputs found
High prevalence of porcine Hokovirus in German wild boar populations
Porcine Hokovirus (PHoV) was recently discovered in Hong Kong. This new Parvovirus of pigs is closely related to the human Parvoviruses 4 and 5 (PARV4/5) and bovine Hokovirus (BHoV). So far, nothing is known about the presence and prevalence of PHoV in regions of the world other than Hong Kong. A study was initiated to investigate PHoV in German wild boars from five different geographical regions, using a newly established quantitative real-time PCR assay. Analysis of collected liver and serum samples revealed high overall prevalence (32.7%; 51/156) of PHoV in wild boars. The prevalence differed between the regions and increased with age. Two near full-length genomes and a large fragment for three additional isolates from different regions were sequenced and used for phylogenetic analysis. The German PHoV sequences from wild boars showed a close relationship with sequences of isolates from Hong Kong
Iatrogenic Subtotal Stenosis of the Right Subclavian Artery Treated With Percutaneous Transluminal Angioplasty
This report describes a rare vascular complication of surgical placement of a marking clip and a possible approach to problem solving. A 55-year-old patient presented with loss of sensation in the fingers and loss of peripheral pulsations in the right arm 4 days after right upper lobectomy for a pT2N1 moderately differentiated adenocarcinoma of the lung. Duplex examination and computed tomography were performed the same day and showed a subtotal stenosis of the right subclavian artery, which was caused by the surgical placement of a metal clip to mark the surgical boundary. Selective angiography was subsequently performed. Percutaneous transluminal angioplasty (PTA) successfully dilated the stenosis and pushed the clip off. Flow in the right subclavian artery (RSA) was completely restored as were neurology and peripheral pulses. In conclusion, arterial stenosis by a surgical (marking) clip may be feasibly treated with PTA
Using zeta-potential measurements to quantify peptide partition to lipid membranes
© The Author(s) 2011. This article is published with open access at Springerlink.com.Open Access: This article is distributed under the terms of the Creative Commons Attribution Noncommercial License which permits any noncommercial use, distribution, and reproduction in any medium, provided the original author(s) and source are credited.Many cellular phenomena occur on the biomembranes. There are plenty of molecules (natural or xenobiotics) that interact directly or partially with the cell membrane. Biomolecules, such as several peptides (e.g., antimicrobial peptides) and proteins, exert their effects at the cell membrane level. This feature makes necessary investigating their interactions with lipids to clarify their mechanisms of action and side effects necessary. The determination of molecular lipid/water partition constants (Kp) is frequently used to quantify the extension of the interaction. The determination of this parameter has been achieved by using different methodologies, such as UV-Vis absorption spectrophotometry, fluorescence spectroscopy and ζ-potential measurements. In this work, we derived and tested a mathematical model to determine the Kp from ζ-potential data. The values obtained with this method were compared with those obtained by fluorescence spectroscopy, which is a regular technique used to quantify the interaction of intrinsically fluorescent peptides with selected biomembrane model systems. Two antimicrobial peptides (BP100 and pepR) were evaluated by this new method. The results obtained by this new methodology show that ζ-potential is a powerful technique to quantify peptide/lipid interactions of a wide variety of charged molecules, overcoming some of the limitations inherent to other techniques, such as the need for fluorescent labeling.This work was partially supported by project PTDC/QUI/ 69937/2006 from Fundação para a Ciência e Tecnologia-Ministério da Ciência, Tecnologia e Ensino Superior (FCT-MCTES, Portugal), and by Fundação Calouste Gulbenkian (Portugal). JMF and MMD also thank FCT-MCTES for grants IMM/BT/37-2010 and SFRH/BD/41750/2007, respectively
Minimal Flavour Violation with hierarchical squark masses
In a supersymmetric model with hierarchical squark masses we analyze a
pattern of flavour symmetry breaking centered on the special role of the top
Yukawa coupling and, by extension, of the full Yukawa couplings for the up-type
quarks. For sufficiently heavy squarks of the first and second generation this
leads to effective Minimal Flavour Violation of the Flavour Changing Neutral
Current amplitudes. For this to happen we determine the bounds on the masses of
the heavy squarks with QCD corrections taken into account, properly including
previously neglected effects. We believe that the view presented in this paper
altogether strengthens the case for hierarchical sfermions.Comment: 13 pages, 1 figure. v2: an equation correcte
Effect of parasympathetic stimulation on brain activity during appraisal of fearful expressions
Autonomic nervous system activity is an important component of human emotion. Mental processes influence bodily physiology, which in turn feeds back to influence thoughts and feelings. Afferent cardiovascular signals from arterial baroreceptors in the carotid sinuses are processed within the brain and contribute to this two-way communication with the body. These carotid baroreceptors can be stimulated non-invasively by externally applying focal negative pressure bilaterally to the neck. In an experiment combining functional neuroimaging (fMRI) with carotid stimulation in healthy participants, we tested the hypothesis that manipulating afferent cardiovascular signals alters the central processing of emotional information (fearful and neutral facial expressions). Carotid stimulation, compared with sham stimulation, broadly attenuated activity across cortical and brainstem regions. Modulation of emotional processing was apparent as a significant expression-by-stimulation interaction within left amygdala, where responses during appraisal of fearful faces were selectively reduced by carotid stimulation. Moreover, activity reductions within insula, amygdala, and hippocampus correlated with the degree of stimulation-evoked change in the explicit emotional ratings of fearful faces. Across participants, individual differences in autonomic state (heart rate variability, a proxy measure of autonomic balance toward parasympathetic activity) predicted the extent to which carotid stimulation influenced neural (amygdala) responses during appraisal and subjective rating of fearful faces. Together our results provide mechanistic insight into the visceral component of emotion by identifying the neural substrates mediating cardiovascular influences on the processing of fear signals, potentially implicating central baroreflex mechanisms for anxiolytic treatment targets
Cognitive reserve in granulin-related frontotemporal dementia: from preclinical to clinical stages
OBJECTIVE
Consistent with the cognitive reserve hypothesis, higher education and occupation attainments may help persons with neurodegenerative dementias to better withstand neuropathology before developing cognitive impairment. We tested here the cognitive reserve hypothesis in patients with frontotemporal dementia (FTD), with or without pathogenetic granulin mutations (GRN+ and GRN-), and in presymptomatic GRN mutation carriers (aGRN+).
METHODS
Education and occupation attainments were assessed and combined to define Reserve Index (RI) in 32 FTD patients, i.e. 12 GRN+ and 20 GRN-, and in 17 aGRN+. Changes in functional connectivity were estimated by resting state fMRI, focusing on the salience network (SN), executive network (EN) and bilateral frontoparietal networks (FPNs). Cognitive status was measured by FTD-modified Clinical Dementia Rating Scale.
RESULTS
In FTD patients higher level of premorbid cognitive reserve was associated with reduced connectivity within the SN and the EN. EN was more involved in FTD patients without GRN mutations, while SN was more affected in GRN pathology. In aGRN+, cognitive reserve was associated with reduced SN.
CONCLUSIONS
This study suggests that cognitive reserve modulates functional connectivity in patients with FTD, even in monogenic disease. In GRN inherited FTD, cognitive reserve mechanisms operate even in presymptomatic to clinical stages
Tearing Out the Income Tax by the (Grass)Roots
Landscapes are increasingly fragmented, and conservation programs have started to look at network approaches for maintaining populations at a larger scale. We present an agent-based model of predator–prey dynamics where the agents (i.e. the individuals of either the predator or prey population) are able to move between different patches in a landscaped network. We then analyze population level and coexistence probability given node-centrality measures that characterize specific patches. We show that both predator and prey species benefit from living in globally well-connected patches (i.e. with high closeness centrality). However, the maximum number of prey species is reached, on average, at lower closeness centrality levels than for predator species. Hence, prey species benefit from constraints imposed on species movement in fragmented landscapes since they can reproduce with a lesser risk of predation, and their need for using anti-predatory strategies decreases.authorCount :
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