448 research outputs found
Investment intermediaries in economic development: Linking public pension funds to urban revitalization
It is difficult for large investors, such as pension funds, to make investments in EDMs because they must make very large investments. The investments in communities of need, however, are usually small. The most successful strategy to overcome these two problems is for investors to work in concert with intermediaries that can aggregate the investments and community partners that understand both the need of communities and know how to tell “the story” to investors.
Cellular and molecular interactions after peripheral and central nerve injury
Injuries to the central nervous system (CNS) result in virtually irreversible neurologic deficits compared to the peripheral nervous system (PNS) where injuries may be followed by some functional recovery. This sharp difference in the regenerative capacity of CNS and PNS is attributed to intrinsic properties of the injured neurons, and the glial cells, specifically the Schwann cell of PNS and the oligodendrocyte of CNS. The myriad of cellular and molecular changes that result following nerve injury are intimately related to whether a regenerative-permissive environment is provided to injured neurons. In this review, we highlight some of the key injury-related cell-molecular changes that are triggered in neurons and glia and how these changes may be related to the promotion of axonal regeneration of injured PNS compared to CNS.Biomedical Reviews 2003; 14: 51-62
The peripheral nervous system: injury and disease
Poor functional outcomes are frequent after peripheral nerve injuries despite the regenerative support of Schwann cells. Whilst motoneurons and to a lesser extent, sensory neurons survive the injuries, outgrowth of axons across the injury site is slow and the neuronal regenerative capacity is progressively reduced when neurons remain without targets and chronically denervated Schwann cells fail to support axon growth. Strategies including brief low frequency electrical stimulation that accelerates axon outgrowth and, in turn, target reinnervation and functional recovery, have excellent potential for translation to human patients. Other strategies including the insertion of cross-bridges between a donor nerve and a recipient denervated nerve stump, are effective in promoting functional outcomes after complete injuries. During muscle reinnervation the properties of the motoneurons and muscle fibers that they supply are rematched that provide some control of muscle force even when regenerating axons are misdirected to foreign targets. Axon sprouting from intact nerves is effective, although limited, in reinnervating denervated muscle fibers after incomplete injuries and in poliomyelitis. Studies in mouse models of amyotrophic lateral sclerosis however, indicate that sprouting is very limited with rapid and preferential loss of the largest and fastest contracting motor units during the asymptomatic phase of the disease
Hydroxychloroquine for chronic myeloid leukemia: complete cure on the horizon?
No abstract available
Cross-boundary collaboration: Key to the conservation puzzle
Conservation science is advancing rapidly, yet the majority of research overlooks a key factor that can play a major role in shaping the outcomes of conservation initiatives: collaboration. Here, we review the importance, benefits and limitations of incorporating collaboration into conservation and specifically into systematic conservation planning, providing a general framework for considering collaboration in conservation planning. Recent work shows that cross-boundary collaboration can have both positive and negative impacts on the outcomes of conservation and management efforts for protected areas, ecosystems, threatened and invasive species. The feasibility of collaboration, its likely effects and associated trade-offs should therefore be explicitly incorporated into conservation science and planning. This will ensure that conservation decisions avoid wasted funding when collaboration is infeasible, promoting collaboration when the benefits outweigh the costs
Long-Term Denervated Rat Schwann Cells Retain Their Capacity to Proliferate and to Myelinate Axons in vitro
Functional recovery is poor after peripheral nerve injury and delayed surgical repair or when nerves must regenerate over long distances to reinnervate distant targets. A reduced capacity of Schwann cells (SCs) in chronically denervated distal nerve stumps to support and interact with regenerating axons may account for the poor outcome. In an in vitro system, we examined the capacity of adult, long-term denervated rat SCs to proliferate and to myelinate neurites in co-cultures with fetal dorsal root ganglion (DRG) neurons. Non-neuronal cells were counted immediately after their isolation from the distal sciatic nerve stumps that were subjected to acute denervation of 7 days or chronic denervation of either 7 weeks or 17 months. Thereafter, equal numbers of the non-neural cells were co-cultured with purified dissociated DRG neurons for 5 days. The co-cultures were then treated with 3H-Thymidine for 24 h to quantitate SC proliferation with S100 immunostaining and autoradiography. After a 24-day period of co-culture, Sudan Black staining was used to visualize and count myelin segments that were elaborated around DRG neurites by the SCs. Isolated non-neural cells from 7-week chronically denervated nerve stumps increased 2.5-fold in number compared to ~2 million in 7 day acutely denervated stumps. There were only <0.2 million cells in the 17-week chronically denervated stumps. Nonetheless, these chronically denervated SCs maintained their proliferative capacity although the capacity was reduced to 30% in the 17-month chronically denervated distal nerve stumps. Moreover, the chronically denervated SCs retained their capacity to myelinate DRG neurites: there was extensive myelination of the neurites by the acutely and chronically denervated SCs after 24 days co-culture. There were no significant differences in the extent of myelination. We conclude that the low numbers of surviving SCs in chronically denervated distal nerve stumps retain their ability to respond to axonal signals to divide and to elaborate myelin. However, their low numbers consequent to their poor survival and their reduced capacity to proliferate account, at least in part, for the poor functional recovery after delayed surgical repair of injured nerve and/or the repair of injured nerves far from their target organs
The Forum: Spring 2004
Spring 2004 journal of the Honors Program at the University of North Dakota. The issue includes stories, poems, essays and art by undergraduate students.https://commons.und.edu/und-books/1054/thumbnail.jp
Systems for grading the quality of evidence and the strength of recommendations I: Critical appraisal of existing approaches The GRADE Working Group
BACKGROUND: A number of approaches have been used to grade levels of evidence and the strength of recommendations. The use of many different approaches detracts from one of the main reasons for having explicit approaches: to concisely characterise and communicate this information so that it can easily be understood and thereby help people make well-informed decisions. Our objective was to critically appraise six prominent systems for grading levels of evidence and the strength of recommendations as a basis for agreeing on characteristics of a common, sensible approach to grading levels of evidence and the strength of recommendations. METHODS: Six prominent systems for grading levels of evidence and strength of recommendations were selected and someone familiar with each system prepared a description of each of these. Twelve assessors independently evaluated each system based on twelve criteria to assess the sensibility of the different approaches. Systems used by 51 organisations were compared with these six approaches. RESULTS: There was poor agreement about the sensibility of the six systems. Only one of the systems was suitable for all four types of questions we considered (effectiveness, harm, diagnosis and prognosis). None of the systems was considered usable for all of the target groups we considered (professionals, patients and policy makers). The raters found low reproducibility of judgements made using all six systems. Systems used by 51 organisations that sponsor clinical practice guidelines included a number of minor variations of the six systems that we critically appraised. CONCLUSIONS: All of the currently used approaches to grading levels of evidence and the strength of recommendations have important shortcomings
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