Norbert Weidner

Bio: Norbert Weidner is an academic researcher from University Hospital Heidelberg. The author has contributed to research in topics: Spinal cord injury & Spinal cord. The author has an hindex of 36, co-authored 143 publications receiving 5404 citations. Previous affiliations of Norbert Weidner include University of California, San Diego & Heidelberg University.

Doublecortin expression levels in adult brain reflect neurogenesis.

Abstract: Progress in the field of neurogenesis is currently limited by the lack of tools enabling fast and quantitative analysis of neurogenesis in the adult brain Doublecortin (DCX) has recently been used as a marker for neurogenesis However, it was not clear whether DCX could be used to assess modulations occurring in the rate of neurogenesis in the adult mammalian central nervous system following lesioning or stimulatory factors Using two paradigms increasing neurogenesis levels (physical activity and epileptic seizures), we demonstrate that quantification of DCX-expressing cells allows for an accurate measurement of modulations in the rate of adult neurogenesis Importantly, we excluded induction of DCX expression during physiological or reactive gliogenesis and excluded also DCX re-expression during regenerative axonal growth Our data validate DCX as a reliable and specific marker that reflects levels of adult neurogenesis and its modulation We demonstrate that DCX is a valuable alternative to techniques currently used to measure the levels of neurogenesis Importantly, in contrast to conventional techniques, analysis of neurogenesis through the detection of DCX does not require in vivo labelling of proliferating cells, thereby opening new avenues for the study of human neurogenesis under normal and pathological conditions

Spontaneous corticospinal axonal plasticity and functional recovery after adult central nervous system injury.

Abstract: Although it is believed that little recovery occurs after adult mammalian spinal cord injury, in fact significant spontaneous functional improvement commonly occurs after spinal cord injury in humans. To investigate potential mechanisms underlying spontaneous recovery, lesions of defined components of the corticospinal motor pathway were made in adult rats in the rostral cervical spinal cord or caudal medulla. Following complete lesions of the dorsal corticospinal motor pathway, which contains more than 95% of all corticospinal axons, spontaneous sprouting from the ventral corticospinal tract occurred onto medial motoneuron pools in the cervical spinal cord; this sprouting was paralleled by functional recovery. Combined lesions of both dorsal and ventral corticospinal tract components eliminated sprouting and functional recovery. In addition, functional recovery was also abolished if dorsal corticospinal tract lesions were followed 5 weeks later by ventral corticospinal tract lesions. We found extensive spontaneous structural plasticity as a mechanism correlating with functional recovery in motor systems in the adult central nervous system. Experimental enhancement of spontaneous plasticity may be useful to promote further recovery after adult central nervous system injury.

Systemic administration of epothilone B promotes axon regeneration after spinal cord injury

Abstract: After central nervous system (CNS) injury, inhibitory factors in the lesion scar and poor axon growth potential prevent axon regeneration Microtubule stabilization reduces scarring and promotes axon growth However, the cellular mechanisms of this dual effect remain unclear Here, delayed systemic administration of a blood-brain barrier–permeable microtubule-stabilizing drug, epothilone B (epoB), decreased scarring after rodent spinal cord injury (SCI) by abrogating polarization and directed migration of scar-forming fibroblasts Conversely, epothilone B reactivated neuronal polarization by inducing concerted microtubule polymerization into the axon tip, which propelled axon growth through an inhibitory environment Together, these drug-elicited effects promoted axon regeneration and improved motor function after SCI With recent clinical approval, epothilones hold promise for clinical use after CNS injury

Isolation and Characterization of Tumorigenic, Stem-like Neural Precursors from Human Glioblastoma

Abstract: Transformed stem cells have been isolated from some human cancers. We report that, unlike other brain cancers, the lethal glioblastoma multiforme contains neural precursors endowed with all of the critical features expected from neural stem cells. Similar, yet not identical, to their normal neural stem cell counterpart, these precursors emerge as unipotent (astroglial) in vivo and multipotent (neuronal-astroglial-oligodendroglial) in culture. More importantly, these cells can act as tumor-founding cells down to the clonal level and can establish tumors that closely resemble the main histologic, cytologic, and architectural features of the human disease, even when challenged through serial transplantation. Thus, cells possessing all of the characteristics expected from tumor neural stem cells seem to be involved in the growth and recurrence of adult human glioblastomas multiforme.

わかりやすい障害者の権利条約 : 知的障害のある人の権利のために = Convention on the rights of persons with disabilities

Abstract: The present report is submitted in response to General Assembly resolution 61/106, by which the Assembly adopted the Convention on the Rights of Persons with Disabilities and the Optional Protocol thereto. As requested by the Assembly, a brief overview of the status of the Convention as at 3 August 2007 is presented. The report also contains a brief description of technical arrangements on staff and facilities made necessary for the effective performance of the functions of the Conference of States Parties and the Committee under the Convention and the Optional Protocol, and a description on the progressive implementation of standards and guidelines for the accessibility of facilities and services of the United Nations system. Recent efforts of the United Nations and agencies to disseminate information on the Convention and the Optional Protocol are also described.