42 research outputs found

    Fisheries rehabilitation in post-tsunami Aceh: Status and needs from participatory appraisals

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    The widespread and long-term nature of the tsunami damage in Aceh province, Indonesia has threatened the continued use of coastal and fisheries resources. This article describes the application of the Rapid Appraisal of Fisheries Management System (RAFMS) methodology and presents key findings from the participatory appraisals in 15 study sites. The focus is on changes in the number and types of fishing boats and fishing effort, consumption and marketing flow patterns and community perspectives on livelihood options. The level of aid (for new boats), mainly from international organizations, has been unevenly distributed with the number of boats in 13 of 15 villages still being well below the pre-tsunami levels. A focus on supplying small vessels may put increased fishing pressure on the near-shore zone. Consumption data and marketing flows suggest that most fishing villages are supplying outside markets and adding considerably to the wider food security of the province. Despite the tsunami, marine fisheries-related livelihoods are still preferred, although there are indications for the potential expansion of livelihoods into the culture of new species. Alternative resource-based livelihoods need to be tested and refined to fit the needs of the current conditions in Aceh to provide viable options for eliminating hunger and reducing poverty

    Fisheries rehabilitation in post-tsunami Aceh: Status and needs from participatory appraisals

    Get PDF
    The widespread and long-term nature of the tsunami damage in Aceh province, Indonesia has threatened the continued use of coastal and fisheries resources. This article describes the application of the Rapid Appraisal of Fisheries Management System (RAFMS) methodology and presents key findings from the participatory appraisals in 15 study sites. The focus is on changes in the number and types of fishing boats and fishing effort, consumption and marketing flow patterns and community perspectives on livelihood options. The level of aid (for new boats), mainly from international organizations, has been unevenly distributed with the number of boats in 13 of 15 villages still being well below the pre-tsunami levels. A focus on supplying small vessels may put increased fishing pressure on the near-shore zone. Consumption data and marketing flows suggest that most fishing villages are supplying outside markets and adding considerably to the wider food security of the province. Despite the tsunami, marine fisheries-related livelihoods are still preferred, although there are indications for the potential expansion of livelihoods into the culture of new species. Alternative resource-based livelihoods need to be tested and refined to fit the needs of the current conditions in Aceh to provide viable options for eliminating hunger and reducing poverty.Disaster, Tsunami

    Design of a five-axis ultra-precision micro-milling machine—UltraMill. Part 1: Holistic design approach, design considerations and specifications

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    High-accuracy three-dimensional miniature components and microstructures are increasingly in demand in the sector of electro-optics, automotive, biotechnology, aerospace and information-technology industries. A rational approach to mechanical micro machining is to develop ultra-precision machines with small footprints. In part 1 of this two-part paper, the-state-of-the-art of ultra-precision machines with micro-machining capability is critically reviewed. The design considerations and specifications of a five-axis ultra-precision micro-milling machine—UltraMill—are discussed. Three prioritised design issues: motion accuracy, dynamic stiffness and thermal stability, formulate the holistic design approach for UltraMill. This approach has been applied to the development of key machine components and their integration so as to achieve high accuracy and nanometer surface finish

    COX-2 Induces Breast Cancer Stem Cells via EP4/PI3K/AKT/NOTCH/WNT Axis

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    Cancer stem-like cells (SLC) resist conventional therapies, necessitating searches for SLC-specific targets. We established that cyclo-oxygenase(COX)-2 expression promotes human breast cancer progression by activation of the prostaglandin(PG)E-2 receptor EP4. Present study revealed that COX-2 induces SLCs by EP4-mediated NOTCH/WNT signaling. Ectopic COX-2 over-expression in MCF-7 and SKBR-3 cell lines resulted in: increased migration/invasion/proliferation, epithelial-mesenchymal transition (EMT), elevated SLCs (spheroid formation), increased ALDH activity and colocalization of COX-2 and SLC markers (ALDH1A, CD44, β-Catenin, NANOG, OCT3/4, SOX-2) in spheroids. These changes were reversed with COX-2-inhibitor or EP4-antagonist (EP4A), indicating dependence on COX-2/EP4 activities. COX-2 over-expression or EP4-agonist treatments of COX-2-low cells caused up-regulation of NOTCH/WNT genes, blocked with PI3K/AKT inhibitors. NOTCH/WNT inhibitors also blocked COX-2/EP4 induced SLC induction. Microarray analysis showed up-regulation of numerous SLC-regulatory and EMT-associated genes. MCF-7-COX-2 cells showed increased mammary tumorigenicity and spontaneous multiorgan metastases in NOD/SCID/IL-2Rγ-null mice for successive generations with limiting cell inocula. These tumors showed up-regulation of VEGF-A/C/D, Vimentin and phospho-AKT, down-regulation of E-Cadherin and enrichment of SLC marker positive and spheroid forming cells. MCF-7-COX-2 cells also showed increased lung colonization in NOD/SCID/GUSB-null mice, an effect reversed with EP4-knockdown or EP4A treatment of the MCF-7-COX-2 cells. COX-2/EP4/ALDH1A mRNA expression in human breast cancer tissues were highly correlated with one other, more marked in progressive stage of disease. In situ immunostaining of human breast tumor tissues revealed co-localization of SLC markers with COX-2, supporting COX-2 inducing SLCs. High COX-2/EP4 mRNA expression was linked with reduced survival. Thus, EP4 represents a novel SLC-ablative target in human breast cancer. Stem Cells 2016;34:2290–2305

    Co-Expression of α9β1 Integrin and VEGF-D Confers Lymphatic Metastatic Ability to a Human Breast Cancer Cell Line MDA-MB-468LN

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    INTRODUCTION AND OBJECTIVES: Lymphatic metastasis is a common occurrence in human breast cancer, mechanisms remaining poorly understood. MDA-MB-468LN (468LN), a variant of the MDA-MB-468GFP (468GFP) human breast cancer cell line, produces extensive lymphatic metastasis in nude mice. 468LN cells differentially express α9β1 integrin, a receptor for lymphangiogenic factors VEGF-C/-D. We explored whether (1) differential production of VEGF-C/-D by 468LN cells provides an autocrine stimulus for cellular motility by interacting with α9β1 and a paracrine stimulus for lymphangiogenesis in vitro as measured with capillary-like tube formation by human lymphatic endothelial cells (HMVEC-dLy); (2) differential expression of α9 also promotes cellular motility/invasiveness by interacting with macrophage derived factors; (3) stable knock-down of VEGF-D or α9 in 468LN cells abrogates lymphangiogenesis and lymphatic metastasis in vivo in nude mice. RESULTS: A comparison of expression of cyclo-oxygenase (COX)-2 (a VEGF-C/-D inducer), VEGF-C/-D and their receptors revealed little COX-2 expression by either cells. However, 468LN cells showed differential VEGF-D and α9β1 expression, VEGF-D secretion, proliferative, migratory/invasive capacities, latter functions being stimulated further with VEGF-D. The requirement of α9β1 for native and VEGF-D-stimulated proliferation, migration and Erk activation was demonstrated by treating with α9β1 blocking antibody or knock-down of α9. An autocrine role of VEGF-D in migration was shown by its impairment by silencing VEGF-D and restoration with VEGF-D. 468LN cells and their soluble products stimulated tube formation, migration/invasiveness of HMVEC-dLy cell in a VEGF-D dependent manner as indicated by the loss of stimulation by silencing VEGF-D in 468LN cells. Furthermore, 468LN cells showed α9-dependent stimulation of migration/invasiveness by macrophage products. Finally, capacity for intra-tumoral lymphangiogenesis and lymphatic metastasis in nude mice was completely abrogated by stable knock-down of either VEGF-D or α9 in 468LN cells. CONCLUSION: Differential capacity for VEGF-D production and α9β1 integrin expression by 468LN cells jointly contributed to their lymphatic metastatic phenotype

    Differential regulation of β2-adrenoceptor and adenosine A2B receptor signalling by GRK and arrestin proteins in arterial smooth muscle

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    Generation of cAMP through Gs-coupled G protein-coupled receptor (GPCR) [e.g. β2-adrenoceptor (β2AR), adenosine A2B receptor (A2BR)] activation, induces arterial smooth muscle relaxation, counteracting the actions of vasoconstrictors. Gs-coupled GPCR signalling is regulated by G protein-coupled receptor kinases (GRK) and arrestin proteins, and dysregulation of Gs/GPCR signalling is thought play a role in the development of hypertension, which may be a consequence of enhanced GRK2 and/or arrestin expression. However, despite numerous studies indicating that β2AR and A2BR can be substrates for GRK/arrestin proteins, currently little is known regarding GRK/arrestin regulation of these endogenous receptors in arterial smooth muscle. Here, endogenous GRK isoenzymes and arrestin proteins were selectively depleted using RNA-interference in rat arterial smooth muscle cells (RASM) and the consequences of this for β2AR- and A2BR-mediated adenylyl cyclase (AC) signalling were determined by assessing cAMP accumulation. GRK2 or GRK5 depletion enhanced and prolonged β2AR/AC signalling, while combined deletion of GRK2/5 has an additive effect. Conversely, activation of AC by A2BR was regulated by GRK5, but not GRK2. β2AR desensitization was attenuated following combined GRK2/GRK5 knockdown, but not by depletion of individual GRKs, arrestins, or by inhibiting PKA. Arrestin3 (but not arrestin2) depletion enhanced A2BR-AC signalling and attenuated A2BR desensitization, while β2AR-AC signalling was regulated by both arrestin isoforms. This study provides a first demonstration of how different complements of GRK and arrestin proteins contribute to the regulation of signalling and desensitization of these important receptors mediating vasodilator responses in arterial smooth muscle
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