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811.
Lazzeri D Larcher L Nicoli F Campisi C Agostini T 《Plastic and reconstructive surgery》2012,130(2):369e-370e; author reply 370e
812.
van Meeteren LA Thorikay M Bergqvist S Pardali E Stampino CG Hu-Lowe D Goumans MJ ten Dijke P 《The Journal of biological chemistry》2012,287(22):18551-18561
Genetic and molecular studies suggest that activin receptor-like kinase 1 (ALK1), a transforming growth factor β (TGF-β) type I receptor, and endoglin, a TGF-β co-receptor, play an essential role in vascular development and pathological angiogenesis. Several agents that interfere with ALK1 and endoglin function are currently in clinical trials for antiangiogenic activity in cancer therapy. One of these agents, PF-03446962 (anti-hALK1 antibody), shows promising results in the clinic. However, its effects on endothelial cell function and mechanism of action are unclear. Here we demonstrate that anti-hALK1 antibody selectively recognizes human ALK1. The anti-hALK1 antibody interfered with bone morphogenetic protein 9 (BMP9)-induced signaling in endothelial cells. Consistent with this notion, anti-hALK1 antibody was found to compete highly efficiently with the binding of the ALK1 ligand BMP9 and TGF-β to ALK1. Moreover, it prevented BMP9-dependent recruitment of co-receptor endoglin into this angiogenesis-mediating signaling complex. In addition, we demonstrated that anti-hALK1 antibody inhibited endothelial cell sprouting but did not directly interfere with vascular endothelial growth factor (VEGF) signaling, VEGF-induced proliferation, and migration of endothelial cells. Finally, we demonstrated that BMP9 in serum is essential for endothelial sprouting and that anti-hALK1 antibody inhibits this potently. Our data suggest that both the VEGF/VEGF receptor and the BMP9/ALK1 pathways are essential for stimulating angiogenesis, and targeting both pathways simultaneously may be an attractive strategy to overcome resistance to antiangiogenesis therapy. 相似文献
813.
Maria Sporbert Helge Bruelheide Gunnar Seidler Petr Keil Ute Jandt Gunnar Austrheim Idoia Biurrun Juan Antonio Campos Andra arni Milan Chytrý Jnos Csiky Els De Bie Jürgen Dengler Valentin Golub John‐Arvid Grytnes Adrian Indreica Florian Jansen Martin Jirouek Jonathan Lenoir Miska Luoto Corrado Marcen Jesper Erenskjold Moeslund Aaron Prez‐Haase Solvita Rsia Vigdis Vandvik Kiril Vassilev Erik Welk 《植被学杂志》2019,30(4):620-632
814.
815.
Alessandra Trinchera Corrado Ciaccia Elena Testani Valentina Baratella Gabriele Campanelli Fabrizio Leteo Stefano Canali 《Ecology and evolution》2019,9(10):5593-5604
The mycorrhizal fungi are symbiotic organisms able to provide many benefits to crop production by supplying a set of ecosystem functions. A recent ecological approach based on the ability of the fungi community to influence plant–plant interactions by extraradical mycelium development may be applied to diversified, herbaceous agroecosystems. Our hypothesis is that the introduction of a winter cereal cover crop (CC) as arbuscular mycorrhizal fungi (AMF)–host plant in an organic rotation can boosts the AMF colonization of the other plants, influencing crop–weed interference. In a 4‐years organic rotation, the effect of two winter cereal CC, rye and spelt, on weed density and AMF colonization was evaluated. The AMF extraradical mycelium on CC and weeds roots was observed by scanning electron microscopy analysis. By joining data of plant density and mycorrhization, we built the mycorrhizal colonization intensity of the Agroecosystem indicator (MA%). Both the CC were colonized by soil AMF, being the mycorrhizal colonization intensity (M%) affected by environmental conditions. Under CC, the weed density was reduced, due to the increase of the reciprocal competition in favor of CC, which benefited from mycorrhizal colonization and promoted the development of AMF extraradical mycelium. Even though non‐host plants, some weed species showed an increased mycorrhizal colonization in presence of CC respect to the control. Under intense rainfall, the MA% was less sensitive to the CC introduction. On the opposite, under highly competitive conditions, both the CC boosted significantly the mycorrhization of coexistent plants in the agroecosystem. The proposed indicator measured the agroecological service provided by the considered CCs in promoting or inhibiting the overall AMF colonization of the studied agroecosystems, as affected by weed selection and growth: It informs about agroecosystem resilience and may be profitably applied to indicate the extent of the linkage of specific crop traits to agroecosystem services, contributing to further develop the functional biodiversity theory. 相似文献
816.
817.
Akaitz Dorronsoro Fernando E. Santiago Diego Grassi Tianpeng Zhang Ruenn Chai Lai Sara J. McGowan Luise Angelini Mitra Lavasani Lana Corbo Aiping Lu Robert W. Brooks Marta GarciaContreras Donna B. Stolz Antonio Amelio Siddaraju V. Boregowda Mohammad Fallahi Adrian Reich Camillo Ricordi Donald G. Phinney Johnny Huard Sai Kiang Lim Laura J. Niedernhofer Paul D. Robbins 《Aging cell》2021,20(4)
Aging drives progressive loss of the ability of tissues to recover from stress, partly through loss of somatic stem cell function and increased senescent burden. We demonstrate that bone marrow‐derived mesenchymal stem cells (BM‐MSCs) rapidly senescence and become dysfunctional in culture. Injection of BM‐MSCs from young mice prolonged life span and health span, and conditioned media (CM) from young BM‐MSCs rescued the function of aged stem cells and senescent fibroblasts. Extracellular vesicles (EVs) from young BM‐MSC CM extended life span of Ercc1 −/− mice similarly to injection of young BM‐MSCs. Finally, treatment with EVs from MSCs generated from human ES cells reduced senescence in culture and in vivo, and improved health span. Thus, MSC EVs represent an effective and safe approach for conferring the therapeutic effects of adult stem cells, avoiding the risks of tumor development and donor cell rejection. These results demonstrate that MSC‐derived EVs are highly effective senotherapeutics, slowing the progression of aging, and diseases driven by cellular senescence. 相似文献
818.
Giuliano Fanelli Corrado Battisti Rachele Malavasi 《Wetlands Ecology and Management》2014,22(5):565-569
In a Mediterranean patchy wetland of central Italy, we analyzed the relationship between the number of bird species, expressed in terms of bird alpha diversity, and plant alpha diversity, expressed as Hill number. This number (the exponential of the Shannon entropy) is considered one of the most strong and reliable indexes of alpha-diversity, synthesizing the information on evenness, richness and diversity in one single metric. We observed a progressive increase of the mean values of bird alpha diversity when plant alpha diversity increases along Hill number. Bird alpha diversity shows an abrupt increase between the first and the second of four categories of plant alpha diversity (0–1, >1–2, >2–3, >3), indicating a threshold response in all the groups considered (breeding, wintering and total bird assemblages). This marked decline of bird species richness at around 1 in the Hill index should represent an alarm for managers: wetland sites at or below this level of plant alpha diversity are likely to be experiencing a drastic decrease in bird species richness, both in spring (breeding birds) and in winter (wintering birds). 相似文献
819.
820.