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Axons undergo Wallerian degeneration distal to a point of injury. Experimental investigations have documented many of the cellular and molecular events that underlie this behaviour. Since relatively little is known about such events in human CNS pathologies and current experimental intervention strategies indicate the possibility of significant axon regeneration along the original degenerated fibre tract, we performed an immunohistochemical investigation of the dynamics of Wallerian degeneration in post mortem spinal cords of patients who died 2 days to 30 years after either cerebral infarction or traumatic spinal cord injury. Neurofilament (NF) staining demonstrated a spatio-temporal pattern of axonal loss within degenerating descending nerve fibre tracts that could be detected close to the lesion as early as 12 days after injury and progressed to an almost complete loss of NF immunoreactivity at survival times of 1 year and longer. Immunohistochemistry for glial fibrillary acidic protein revealed a late astrocytic reaction starting at 4 months after injury in the degenerating tracts, leading to the long-term deposition of a dense astrocytic scar. These events were accompanied by the gradual reduction of myelin basic protein in affected nerve fibre tracts, leading to almost complete loss by 3 years after injury. Since the extracellular matrix molecule chondroitin sulphate proteoglycan (CSPG) is known to be strongly inhibitory for axonal regeneration and to be a major component of gliotic scar tissues, we investigated the possible deposition of CSPG within the degenerating nerve fibre tracts. Apart from a local up-regulation close to the lesion site, our results show no enhanced CSPG expression within degenerated tracts at any survival time. This suggests that despite the apparent lack of CSPG in Wallerian degeneration, the slow reduction of CNS myelin and the long-term deposition of a dense astrocytic scar may present an environment that is non-supportive for axon regrowth

Application of indicators exemplified by the prescribing conduct of physicians in a specific region of northern Germany showing deficits before implementation of the new GSG (Health Structure Law). The prescriptions of physicians in a specific region of northern Germany were examined to see whether the quality of drug therapy in this region, which showed deficits before the implementation of the GSG, had been influenced by this law. After encoding the prescription data the 100 most often prescribed drugs were identified as physician-related the resulting costs determined and arranged in order of precedence ("medicine charts"). The indicators were defined as to which "medicine-chart" drug they related, to facilitate a qualitative analysis of the prescriptions. The indicators were: Drugs, whose therapeutic advantage is not proven Drugs based on obsolete therapeutic concepts Drugs with lower-priced and/or therapeutic equal alternatives Standard-Therapeutics.