1,721,082 research outputs found
Does youth mean vigorous and age, feeble biological repair mechanisms?
All living creatures are subject to aging, but our understanding of what governs aging is limited. In the course of a lifetime, with the constant renewal of the organic substance of living creatures errors arise, e.g. in the formation, disposal, and reproduction of DNA, proteins and lipids or in the constant substitution of aging cells in the organs. These errors are recognized and generally counterbalanced by appropriate repair mechanisms. This process is obviously determined partly by environmental influences (e.g. UV radiation, oxidizing influences, thermal shock) and genetic factors (such as the significance of so-called survival genes and gene mutations). In this paper the authors both explain and test the hypothesis that the aging of organs and organisms is the consequence of and not the reason for a progressive weakening of the repair mechanisms throughout life
NEURONAL PROTECTION IN NEUROLOGICAL DISEASE
Several types of lesions of the mature central nervous system (CNS), such as craniocerebral trauma or spinal cord trauma, may initiate secondary cascades, which may cause damage to primarily uninjured neurons. The exact mechanisms which cause neuronal cell death are still unknown. It has been suggested that retrogradely transported target-derived neurotrophic factors which are neccessary for neuronal survival might be lacking after certain types of lesions. On the other hand, neurons might be damaged by calcium-overload resulting from excessive release of excitatory amino acids (EAAs) after trauma. The present review summarizes current concepts of post-traumatic neuronal cell damage with a focus on the putative neuroprotective role of calcium channel blockers and their interaction with glutamate mediated cytotoxicity, neurotrophic factors and free radicals
Gene therapy of neurological disorders. Experimental paradigms and clinical perspectives
So far, it has not been possible to treat many neurological conditions causally. However, in the past few years underlying genetic defects have been characterized for a substantial number of neurodegenerative disorders. Experimental methods have been developed that allow for efficient gene transfer into defined regions of the mammalian CNS. Such techniques can be applied to deliver genes into target cells of a recipient organism or to transfer genetically modified cells into defined regions of the CNS. Candidate genes for gene therapy are those encoding for neurotrophins and neurotransmitters for symptomatic therapy and, in the case of neurodegenerative disorders with localized gene defects, the wild-type allele as a causal treatment approach. In this review article, we describe some of the most widely used strategies for gene transfer to the CNS. We also report on the results obtained with animal models for human disease, and discuss both the chances and problems of gene therapy approaches in clinical medicine
NEURONAL PROTECTION IN NEUROLOGICAL DISEASE
Several types of lesions of the mature central nervous system (CNS), such as craniocerebral trauma or spinal cord trauma, may initiate secondary cascades, which may cause damage to primarily uninjured neurons. The exact mechanisms which cause neuronal cell death are still unknown. It has been suggested that retrogradely transported target-derived neurotrophic factors which are neccessary for neuronal survival might be lacking after certain types of lesions. On the other hand, neurons might be damaged by calcium-overload resulting from excessive release of excitatory amino acids (EAAs) after trauma. The present review summarizes current concepts of post-traumatic neuronal cell damage with a focus on the putative neuroprotective role of calcium channel blockers and their interaction with glutamate mediated cytotoxicity, neurotrophic factors and free radicals
Gene therapy of neurological disorders. Experimental paradigms and clinical perspectives
So far, it has not been possible to treat many neurological conditions causally. However, in the past few years underlying genetic defects have been characterized for a substantial number of neurodegenerative disorders. Experimental methods have been developed that allow for efficient gene transfer into defined regions of the mammalian CNS. Such techniques can be applied to deliver genes into target cells of a recipient organism or to transfer genetically modified cells into defined regions of the CNS. Candidate genes for gene therapy are those encoding for neurotrophins and neurotransmitters for symptomatic therapy and, in the case of neurodegenerative disorders with localized gene defects, the wild-type allele as a causal treatment approach. In this review article, we describe some of the most widely used strategies for gene transfer to the CNS. We also report on the results obtained with animal models for human disease, and discuss both the chances and problems of gene therapy approaches in clinical medicine
Mechanisms underlying recovery of eye-head coordination following bilateral labyrinthectomy in monkeys
Biological effects of low-dose TBI on chronic-progressive MS patients: preliminary results of a double blind study.
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