Inflammation and Wnt signaling: target for immunomodulatory therapy?

Wnt proteins comprise a large family of highly conserved glycoproteins known for their role in development, cell fate specification, tissue regeneration, and tissue homeostasis. Aberrant Wnt signaling is linked to developmental defects, malignant transformation, and carcinogenesis as well as to inflammation. Mounting evidence from recent research suggests that a dysregulated activation of Wnt signaling is involved in the pathogenesis of chronic inflammatory diseases, such as neuroinflammation, cancer-mediated inflammation, and metabolic inflammatory diseases. Recent findings highlight the role of Wnt in the modulation of inflammatory cytokine production, such as NF-kB signaling and in innate defense mechanisms as well as in the bridging of innate and adaptive immunity. This sparked the development of novel therapeutic treatments against inflammatory diseases based on Wnt modulation. Here, we summarize the role and function of the Wnt pathway in inflammatory diseases and focus on Wnt signaling as underlying master regulator of inflammation that can be therapeutically targeted.Stemcel biology/Regenerative medicine (incl. bloodtransfusion

Quasispecies Spatial Models for RNA Viruses with Different Replication Modes and Infection Strategies

Empirical observations and theoretical studies suggest that viruses may use different replication strategies to amplify their genomes, which impact the dynamics of mutation accumulation in viral populations and therefore, their fitness and virulence. Similarly, during natural infections, viruses replicate and infect cells that are rarely in suspension but spatially organized. Surprisingly, most quasispecies models of virus replication have ignored these two phenomena. In order to study these two viral characteristics, we have developed stochastic cellular automata models that simulate two different modes of replication (geometric vs stamping machine) for quasispecies replicating and spreading on a two-dimensional space. Furthermore, we explored these two replication models considering epistatic fitness landscapes (antagonistic vs synergistic) and different scenarios for cell-to-cell spread, one with free superinfection and another with superinfection inhibition. We found that the master sequences for populations replicating geometrically and with antagonistic fitness effects vanished at low critical mutation rates. By contrast, the highest critical mutation rate was observed for populations replicating geometrically but with a synergistic fitness landscape. Our simulations also showed that for stamping machine replication and antagonistic epistasis, a combination that appears to be common among plant viruses, populations further increased their robustness by inhibiting superinfection. We have also shown that the mode of replication strongly influenced the linkage between viral loci, which rapidly reached linkage equilibrium at increasing mutations for geometric replication. We also found that the strategy that minimized the time required to spread over the whole space was the stamping machine with antagonistic epistasis among mutations. Finally, our simulations revealed that the multiplicity of infection fluctuated but generically increased along time

Two-level HARQ for turbo coded cooperation

International audienceWireless networks can exploit an implicit distributed diversity by the use of cooperative systems thanks to the broadcast nature of the radio link. Cooperation leads to improvements in terms of throughput and/or performance and decreases the sensitivity to channel variations. In this paper, a practical approach for a two-user cooperative wireless network is proposed based on a particular hybrid automatic repeat request (HARQ) protocol and turbo coded cooperation. In particular, we propose a two-level ARQ protocol where decision on retransmission is conditioned by two levels; first by the feedback from the destination and second by the feedback from the partner node. The proposed two-level ARQ protocol, combined with turbo coded cooperation, is designed to guarantee inter-user channel improvement through the relay-level ARQ, and consequently better overall system performance and higher throughput by controlling retransmission at destination side

Two-Level HARQ for turbo coded cooperation: system retransmission gain and optimal time allocation

International audienceHybrid automatic repeat request (HARQ) is a wellknown technique for improving system throughput and link performance of wireless communication systems, including cooperative communication systems. In this paper, we exploit the limited feedback applied to the two-source turbo coded cooperation scheme to define a particular cooperative HARQ protocol, called two-level HARQ, where the decision on retransmission at each node is conditioned by two levels: first by the feedback from the destination and second by the feedback from the partner node. To evaluate the performance improvement of this cooperative HARQ system over the original turbo coded cooperation system in terms of frame error probability, we define the system retransmission gain. This gain serves as a decision parameter to determine the conditions under which the cooperative HARQ protocol is useful. Finally, optimal time resource allocation is explored, offering sizable performance improvements

Two-level HARQ for turbo coded cooperation

International audienceWireless networks can exploit an implicit distributed diversity by the use of cooperative systems thanks to the broadcast nature of the radio link. Cooperation leads to improvements in terms of throughput and/or performance and decreases the sensitivity to channel variations. In this paper, a practical approach for a two-user cooperative wireless network is proposed based on a particular hybrid automatic repeat request (HARQ) protocol and turbo coded cooperation. In particular, we propose a two-level ARQ protocol where decision on retransmission is conditioned by two levels; first by the feedback from the destination and second by the feedback from the partner node. The proposed two-level ARQ protocol, combined with turbo coded cooperation, is designed to guarantee inter-user channel improvement through the relay-level ARQ, and consequently better overall system performance and higher throughput by controlling retransmission at destination side

Volatile and phenolic contents and antioxidant and antibacterial properties of Tunisian milk thistle and mastic oils

The present study examined the chemical compositions as well as the antioxidant and antimicrobial activities of the vegetal oils of milk thistle (Silybum marianum) (MTO) and mastic (Pistacia lentiscus) (MO). The mastic oil extract was shown to have higher total phenolic and flavonoid contents than the oil extract of the milk thistle. The fatty acid and sterol compositions of the oil extracts were determined using gas chromatography coupled to flame ionization detection (GC-FID). The main fatty acids identified were palmitic, oleic, and linoleic acids. The main sterols found in milk thistle oil were beta-sitosterol and campesterol, followed by Delta-7-stigmastenol, stigmasterol, Delta-7-avenasterol, and Delta-5-avenasterol. The most abundant sterol in mastic oil was beta-sitosterol, followed by campesterol, Delta-5-avenasterol, and stigmasterol. The volatile compounds of the two vegetal oils were evaluated by headspace solid-phase microextraction (HS-SPME). In both oils, monoterpenes and non-terpenes were found to be the dominant volatile compounds in the mastic and milk thistle vegetal oils. 1,8-Cineole, methylpyrazine, 2,5-dimethylpyrazine, and hexanal were found to be the major volatile compounds of milk thistle oil, whereas myrcene and alpha-pinene were the major volatile compounds found in mastic oil. The antioxidant activities of the oil extracts were evaluated using various methods, such as DPPH, the ferric reducing power, the iron-chelating effect, and the beta-carotene bleaching assay. In all methods, mastic oil exhibited a higher activity than milk thistle oil. Furthermore, both oils exhibited antibacterial activity, but mastic oil was the most potent, particularly against Gram-negative bacteria. Given their high total phenolic and flavonoid contents, the presence of volatile bioactive compounds, and their sterol and fatty acid compositions, the two oil extracts possess high potential for pharmaceutical and cosmetic applications and for utilization as natural preservative ingredients in food

Purification and Characterization of two novel hemiscorpius Lepturus Scorpion venom-Derived Phospolipases A(2) which inhibit angiogenesis un vitro

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MIMO systems for turbo coded cooperation over orthogonal and non-orthogonal channels

International audienceMultiple-input multiple-output (MIMO) systems can be adopted in cooperative wireless networks to bring further space diversity or/and to improve the throughput of the system. In this paper, we evaluate the performance of MIMO applied to a turbo coded cooperation system. The considered system is studied under two scenarios where the sources transmit over either orthogonal channels or non-orthogonal channels. For the latter,interleave-division multiple-access (IDMA) is used for multi-source detection. We evaluate the performance improvement in terms of reliability (frame error rate) and efficiency (throughput efficiency), and determine the channel conditions where adopting MIMO in addition to cooperation is beneficial