Reelin Controls Progenitor Cell Migration in the Healthy and Pathological Adult Mouse Brain

Understanding the signals that control migration of neural progenitor cells in the adult brain may provide new therapeutic opportunities. Reelin is best known for its role in regulating cell migration during brain development, but we now demonstrate a novel function for reelin in the injured adult brain. First, we show that Reelin is upregulated around lesions. Second, experimentally increasing Reelin expression levels in healthy mouse brain leads to a change in the migratory behavior of subventricular zone-derived progenitors, triggering them to leave the rostral migratory stream (RMS) to which they are normally restricted during their migration to the olfactory bulb. Third, we reveal that Reelin increases endogenous progenitor cell dispersal in periventricular structures independently of any chemoattraction but via cell detachment and chemokinetic action, and thereby potentiates spontaneous cell recruitment to demyelination lesions in the corpus callosum. Conversely, animals lacking Reelin signaling exhibit reduced endogenous progenitor recruitment at the lesion site. Altogether, these results demonstrate that beyond its known role during brain development, Reelin is a key player in post-lesional cell migration in the adult brain. Finally our findings provide proof of concept that allowing progenitors to escape from the RMS is a potential therapeutic approach to promote myelin repair

HB 24, Making an Appropriation for a Review of the Environmental Review Process - Statement for House Committee on Planning, Energy and Environmental Protection Public Hearing - February 2, 1989

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Agroforestry in the Pacific Islands: Systems for Sustainability

The replacement of forest with human domesticates figures as one of the most ancient relationships between humanity and the environment. What is new is the rate and scale at which forests are being cleared to make way for agriculture. With the possibility looming of a total loss of tropical forests, there is now a lively interest in making the place where farming and forests meet more harmonious. Agroforestry - which, simply expressed, might be understood to refer to farming with trees rather than without - represents a powerful harmonizer between the two competitors. This book describes the diverse traditional agroforestry systems that have evolved over thousands of years in the Pacific islands. Based on extensive field observations and a wide range of published sources, this study of the agroforestry systems and their hundreds of component trees - including detailed data on 100 of the most useful trees in the Pacific - of Polynesia, Micronesia and Melanesia shows how these systems and their component trees have contributed environmental stability and profound utilitarian value to Pacific Island societies for millennia and thus argues convincingly for the wisdom of protecting and using the existing systems and trees in current forestry, agricultural, and agroforestry development projects, rather than replacing them with introduced systems and plants or allowing them to deteriorate because of commercial pressures or ignorance. As the most comprehensive single source on agroforestry to date, this book will be a must for scholars as well as development agents, planners, aid officials, and foresters.United Nations University, Japan1. Introduction, R.R. Thaman and W.C. Clarke 2. Pacific Island Agroforestry: Functional and Utilitarian Diversity, R.R. Thaman and W.C. Clarke 3. Agroforestry in Melanesia: Case-Studies from Papua New Guinea and the Solomon Islands, W.C. Clarke, R.R. Thaman and H.I. Manner 4. Agroforestry in Melanesia: Case-Studies from Vanuatu and Fiji, R.R. Thaman and W.C. Clarke 5. Agroforestry in Polynesia, R.R. Thaman, W.C. Clarke and B. Decker 6. Agroforestry in Micronesia, H.I. Manner, W.C. Clarke and R.R. Thaman 7. Pacific Island Urban Agroforestry, R.R. Thaman 8. Agroforestry on Smallholder Sugar-Cane Farms in Fiji, R.R. Thaman 11.Appendix: One Hundred Pacific Island Agroforestry Trees, R.R. Thama