Showing papers by "Michael Schumacher published in 2008"

Etifoxine improves peripheral nerve regeneration and functional recovery

Abstract: Peripheral nerves show spontaneous regenerative responses, but recovery after injury or peripheral neuropathies (toxic, diabetic, or chronic inflammatory demyelinating polyneuropathy syndromes) is slow and often incomplete, and at present no efficient treatment is available. Using well-defined peripheral nerve lesion paradigms, we assessed the therapeutic usefulness of etifoxine, recently identified as a ligand of the translocator protein (18 kDa) (TSPO), to promote axonal regeneration, modulate inflammatory responses, and improve functional recovery. We found by histologic analysis that etifoxine therapy promoted the regeneration of axons in and downstream of the lesion after freeze injury and increased axonal growth into a silicone guide tube by a factor of 2 after nerve transection. Etifoxine also stimulated neurite outgrowth in PC12 cells, and the effect was even stronger than for specific TSPO ligands. Etifoxine treatment caused a marked reduction in the number of macrophages after cryolesion within the nerve stumps, which was rapid in the proximal and delayed in the distal nerve stumps. Functional tests revealed accelerated and improved recovery of locomotion, motor coordination, and sensory functions in response to etifoxine. This work demonstrates that etifoxine, a clinically approved drug already used for the treatment of anxiety disorders, is remarkably efficient in promoting acceleration of peripheral nerve regeneration and functional recovery. Its possible mechanism of action is discussed, with reference to the neurosteroid concept. This molecule, which easily enters nerve tissues and regulates multiple functions in a concerted manner, offers promise for the treatment of peripheral nerve injuries and axonal neuropathies.

CASCOM: Intelligent Service Coordination in the Semantic Web

Abstract: This book presents the design, implementation and validation of a value-added supportive infrastructure for Semantic Web based business application services across mobile and fixed networks, applied to an emergency healthcare application. This infrastructure has been realized by the CASCOM European research project. For end users, the CASCOM framework provides seamless access to semantic Web services anytime, anywhere, by using any mobile computing device. For service providers, CASCOM offers an innovative development platform for intelligent and mobile business application services in the Semantic Web. The essential approach of CASCOM is the innovative inter-disciplinary combination of intelligent agent, Semantic Web, peer-to-peer, and mobile computing technology. Conventional peer-to-peer computing environments are extended with components for mobile and wireless communication. Semantic Web services are provided by peer software agents, which exploit the coordination infrastructure to efficiently operate in highly dynamic environments. The generic coordination support infrastructure includes efficient communication means, support for context-aware adaptation techniques, as well as flexible, resource-efficient service discovery, execution, and composition planning. The book has three main parts. First, the state-or-the-art is reviewed in related research fields. Then, a full proof-of-concept design and implementation of the generic infrastructure is presented. Finally, quantitative and qualitative analysis is presented on the basis of the field trials of the emergency application.

Modeling and Design of an Agent-Based Micro-simulation of the Swiss Highway Network

Abstract: Multiagent simulations can be elegantly modeled and designed by enhancing the role of the environment in which agents evolve, called the agent environment. In particular, the agent environment may have the role of a governing infrastructure that regulates with laws or norms the actions taken by the agents. The focus of modeling and design is thus shifted from a subjective view of agents towards a more objective view of the whole multiagent system. In this paper, we apply the idea of a governing environment to model and design a multi-agent system for a micro-simulation of the Swiss highway network. The goal of the simulation is to show how traffic jams and accordion phenomena may be handled with appropriate local regulations on speed limits. A natural modeling would give segments the capacity to regulate the speed based on observed local events. We developed the simulation platform from scratch in order to accommodate our design choices and a realistic complexity. This paper presents in details our modeling and design choices, and first experimental results.

Extending peer-to-peer networks for approximate search

Abstract: This paper proposes a way to enable approximate queries in a peer-to-peer network by using a special encoding function and error correcting codes. The encoding function maintains neighborhood relationships so that two similar inputs will result in two similar outputs. The error correcting code is then used to group the similar encoded values around special codewords. In this manner, similar content is located as close as possible in the network. The algorithm is tested in a simulated environment on a HyperCube network overlay.

Distributed Directories of Web Services

Abstract: This chapter presents WSDir, the federated directory system used in CASCOM. Its main functionality is to let heterogeneous Semantic Web Service descriptions be registered and searched by certain clients. As such, it realizes a lookup function with basic retrieval schemes.