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51.
Muscular dystrophies are among the most common human genetic diseases and are characterized by progressive muscle degeneration. Muscular dystrophies result from genetic defects in components of the dystrophin-glycoprotein complex (DGC), a multimeric complex found in the muscle cell plasma membrane. The DGC links the intracellular cytoskeleton to the extracellular matrix and is thought to be important for maintaining the mechanical integrity of muscles and organizing signalling molecules. The exact role of the DGC in the pathogenesis of disease has, however, remained uncertain. Mutations in Caenorhabditis elegans DGC genes lead to specific defects in coordinated movement and can also cause muscle degeneration. Here we show that mutations in the gene snf-6 result in phenotypes indistinguishable from those of the DGC mutants, and that snf-6 encodes a novel acetylcholine/choline transporter. SNF-6 mediates the uptake of acetylcholine at neuromuscular junctions during periods of increased synaptic activity. SNF-6 also interacts with the DGC, and mutations in DGC genes cause a loss of SNF-6 at neuromuscular junctions. Improper clearing of acetylcholine and prolonged excitation of muscles might contribute to the pathogenesis of muscular dystrophies. 相似文献
52.
53.
Hellström M Phng LK Hofmann JJ Wallgard E Coultas L Lindblom P Alva J Nilsson AK Karlsson L Gaiano N Yoon K Rossant J Iruela-Arispe ML Kalén M Gerhardt H Betsholtz C 《Nature》2007,445(7129):776-780
In sprouting angiogenesis, specialized endothelial tip cells lead the outgrowth of blood-vessel sprouts towards gradients of vascular endothelial growth factor (VEGF)-A. VEGF-A is also essential for the induction of endothelial tip cells, but it is not known how single tip cells are selected to lead each vessel sprout, and how tip-cell numbers are determined. Here we present evidence that delta-like 4 (Dll4)-Notch1 signalling regulates the formation of appropriate numbers of tip cells to control vessel sprouting and branching in the mouse retina. We show that inhibition of Notch signalling using gamma-secretase inhibitors, genetic inactivation of one allele of the endothelial Notch ligand Dll4, or endothelial-specific genetic deletion of Notch1, all promote increased numbers of tip cells. Conversely, activation of Notch by a soluble jagged1 peptide leads to fewer tip cells and vessel branches. Dll4 and reporters of Notch signalling are distributed in a mosaic pattern among endothelial cells of actively sprouting retinal vessels. At this location, Notch1-deleted endothelial cells preferentially assume tip-cell characteristics. Together, our results suggest that Dll4-Notch1 signalling between the endothelial cells within the angiogenic sprout serves to restrict tip-cell formation in response to VEGF, thereby establishing the adequate ratio between tip and stalk cells required for correct sprouting and branching patterns. This model offers an explanation for the dose-dependency and haploinsufficiency of the Dll4 gene, and indicates that modulators of Dll4 or Notch signalling, such as gamma-secretase inhibitors developed for Alzheimer's disease, might find usage as pharmacological regulators of angiogenesis. 相似文献
54.
Greenman C Stephens P Smith R Dalgliesh GL Hunter C Bignell G Davies H Teague J Butler A Stevens C Edkins S O'Meara S Vastrik I Schmidt EE Avis T Barthorpe S Bhamra G Buck G Choudhury B Clements J Cole J Dicks E Forbes S Gray K Halliday K Harrison R Hills K Hinton J Jenkinson A Jones D Menzies A Mironenko T Perry J Raine K Richardson D Shepherd R Small A Tofts C Varian J Webb T West S Widaa S Yates A Cahill DP Louis DN Goldstraw P Nicholson AG Brasseur F Looijenga L Weber BL Chiew YE DeFazio A 《Nature》2007,446(7132):153-158
Cancers arise owing to mutations in a subset of genes that confer growth advantage. The availability of the human genome sequence led us to propose that systematic resequencing of cancer genomes for mutations would lead to the discovery of many additional cancer genes. Here we report more than 1,000 somatic mutations found in 274 megabases (Mb) of DNA corresponding to the coding exons of 518 protein kinase genes in 210 diverse human cancers. There was substantial variation in the number and pattern of mutations in individual cancers reflecting different exposures, DNA repair defects and cellular origins. Most somatic mutations are likely to be 'passengers' that do not contribute to oncogenesis. However, there was evidence for 'driver' mutations contributing to the development of the cancers studied in approximately 120 genes. Systematic sequencing of cancer genomes therefore reveals the evolutionary diversity of cancers and implicates a larger repertoire of cancer genes than previously anticipated. 相似文献
55.
Janet McIntyre-Mills 《Systemic Practice and Action Research》2017,30(5):447-469
The paper responds to the 2030 Development Agenda and suggests a way to enhance representation and accountability by extending the Millennium Goals and UN Sustainable Development Agenda. It summarises the content of a forthcoming volume for the Contemporary Systems Series entitled: Towards a Planetary passport for Representation, Accountability and Re-generation’. The paper reflect on studies of alternative architectures for democracy and governance and suggests a way to extend local engagement in social, economic and environmental decision making. The paper discusses a new architectures for democracy and better governance through:
相似文献
- Addressing the issue of a priori norms and a posteriori measures for transformation towards re-generative living
- Finding ways to match social, cultural, economic and environmental decisions to perceived needs with a focus on food, energy and water security
- Narrowing the gap between perceived needs and the way resources are distributed and the way it impacts on service outcomes.
56.
Janet McIntyre-Mills Lisman Manurung Hetifah Sjaifudian Sumarto Yuyu Komariya 《Systemic Practice and Action Research》2009,22(3):149-171
Balancing individual and collective interests is the challenge in Indonesia and in Australia, where the challenge is (a) to
enable decentralised involvement in decisions to enhance a sense of attachment to an inclusive democracy and (b) achieve careful
evidence based policy to guide the use of resources for the common good.
相似文献
Yuyu KomariyaEmail: |
57.
Janet McIntyre-Mills 《Systemic Practice and Action Research》2009,22(3):127-137
This volume reflects on the program of research undertaken by members and associates of the International Sociological Association’s
Joint Session of Research Committee 10 on Participation and Research Committee 51 on sociocybernetics and the graduates and
contributors to the Flinders University research cluster on user centric design to enhance representation and accountability
for a sustainable future.
相似文献
Janet McIntyre-MillsEmail: |
58.
The genome of woodland strawberry (Fragaria vesca) 总被引:3,自引:0,他引:3
Shulaev V Sargent DJ Crowhurst RN Mockler TC Folkerts O Delcher AL Jaiswal P Mockaitis K Liston A Mane SP Burns P Davis TM Slovin JP Bassil N Hellens RP Evans C Harkins T Kodira C Desany B Crasta OR Jensen RV Allan AC Michael TP Setubal JC Celton JM Rees DJ Williams KP Holt SH Ruiz Rojas JJ Chatterjee M Liu B Silva H Meisel L Adato A Filichkin SA Troggio M Viola R Ashman TL Wang H Dharmawardhana P Elser J Raja R Priest HD Bryant DW Fox SE Givan SA Wilhelm LJ Naithani S Christoffels A Salama DY 《Nature genetics》2011,43(2):109-116
59.
Tarpey PS Raymond FL Nguyen LS Rodriguez J Hackett A Vandeleur L Smith R Shoubridge C Edkins S Stevens C O'Meara S Tofts C Barthorpe S Buck G Cole J Halliday K Hills K Jones D Mironenko T Perry J Varian J West S Widaa S Teague J Dicks E Butler A Menzies A Richardson D Jenkinson A Shepherd R Raine K Moon J Luo Y Parnau J Bhat SS Gardner A Corbett M Brooks D Thomas P Parkinson-Lawrence E Porteous ME Warner JP Sanderson T Pearson P Simensen RJ Skinner C Hoganson G Superneau D Wooster R Bobrow M 《Nature genetics》2007,39(9):1127-1133
60.
This paper presents a conceptual framework for using energy as a vehicle for holistic development to address: poverty, gender discrimination, community involvement in decision making on social, economic, and environmental issues. The approach is systemic and participatory ironically, energy is always seen or considered in fragmentation from other areas and as a technical subject, without considering it in less literal and more metaphorical terms as an end and means of communication. Energy should be seen holistically. Holism is based on a profound understanding of the interconnectedness of the various parts and their relationship to the whole. The point made in this paper is that, by adding energy to the development plan, we solve nothing unless we also consider community mobilization, participatory approaches, and the role of gender in development. Pradhan's research in Nepal has demonstrated that if one thinks of energy only in technical terms and development projects strive to provide more electricity, the interventions can paradoxically just add more drudgery to the lives of women, unless policies consider energy within the context of the whole social, political, economic, and environmental system. Energy provision is more than merely a technical intervention. Participation uses human energy and the creative energy of human beings in a different way. The heart of participatory development is co-creating (in the sense used by Reason, 1988, 2002) understanding based on communication that is generative in the sense used by Paulo Freire. Generative understanding provides a different kind of energy, based on resonance. So this is a play on words when we place energy in a technical sense and energy in a human sense at the center of development. Also, physicists would argue that energy needs to be considered far wore widely as a basis for communication and life. Some also argue that energy is the basis of all organic and inorganic matter in the universe; it is the communication across subatomic matter. 相似文献