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Lucy E. Ridding Adrian C. Newton Sally A. Keith Robin M. Walls Anita Diaz Richard F. Pywell James M. Bullock 《Ecography》2021,44(1):33-43
The extinction debt, delayed species extinctions following landscape degradation, is a widely discussed concept. But a consensus about the prevalence of extinctions debts is hindered by a multiplicity of methods and a lack of comparisons among habitats. We applied three contrasting species–area relationship methods to test for plant community extinction debts in three habitats which had different degradation histories over the last century: calcareous grassland, heathland and woodland. These methods differ in their data requirements, with the first two using information on past and current habitat area alongside current species richness, whilst the last method also requires data on past species richness. The most data‐intensive, and hence arguably most reliable method, identified extinction debts across all habitats for specialist species, whilst the other methods did not. All methods detected an extinction debt in calcareous grassland, which had undergone the most severe degradation. We conclude that some methods failed to detect an extinction debt, particularly in habitats that have undergone moderate degradation. Data on past species numbers are required for the most reliable method; as such data are rare, extinction debts may be under‐reported. 相似文献
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Alice Toso Simona Schifano Charlotte Oxborough Krista McGrath Luke Spindler Anabela Castro Lucy Evangelista Vanessa Filipe Maria José Gonçalves Antonio Marques Inês Mendes da Silva Raquel Santos Maria João Valente Iona McCleery Michelle Alexander 《American journal of physical anthropology》2021,176(2):208-222
45.
Elizabeth E. Hieb Edem A. Eniang Lucy W. Keith-Diagne Ruth H. Carmichael 《The Journal of wildlife management》2021,85(4):674-685
Globally, increasing coastal development requires construction and maintenance of transportation infrastructure that affects terrestrial and aquatic ecosystems. Construction of bridges as part of transportation networks introduces a series of risks to aquatic species near construction zones. We reviewed relevant literature and obtained exemplary case studies to synthesize potential effects of bridge construction on the West Indian manatee (Trichechus manatus), a nearshore megafauna species vulnerable to human activities. Stages of bridge construction including dredging, pile driving, and installation and assembly of bridge components each involve potential direct and indirect effects on manatees. Direct effects such as vessel interactions, entanglement or ingestion, and entrainment may result in acute physical injury or mortality. Indirect effects from construction such as habitat obstruction or degradation and increased noise from construction activities can alter behavior and intraspecies communication and reduce access to essential resources. Some effects of construction may be immediately difficult to quantify, but cumulative effects through time can result in major habitat and species loss. To prevent large-scale negative effects of construction on manatees and other aquatic species, use and evaluation of mitigation strategies should be implemented pre-, during, and post-construction. As the global human population increasingly occupies coastal zones, effective planning of coastal development, including bridge and other in-water construction, will be essential to support conservation and recovery efforts for manatees and other species at risk in these areas. © 2021 The Wildlife Society. 相似文献
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Kiran Nistala Hemlata Varsani Helmut Wittkowski Thomas Vogl Petra Krol Vanita Shah Kamel Mamchaoui Paul A Brogan Johannes Roth Lucy R Wedderburn 《Arthritis research & therapy》2013,15(5):R131
Introduction
The aetiopathogenesis of juvenile dermatomyositis (JDM) remains poorly understood. In particular the contribution of monocytes or macrophages, which are frequently observed to be an infiltrate within muscle tissue very early in the disease process, is unknown. We hypothesised that these cells secrete the pro-inflammatory myeloid related protein (MRP) 8/14 which may then contribute to muscle pathology in JDM.Methods
In this study of 56 JDM patients, serum MRP8/14 levels were compared with clinical measures of disease activity. Muscle biopsies taken early in disease were assessed by immunohistochemistry to determine the frequency and identity of MRP-expressing cells. The effects of MRP stimulation and endoplasmic reticulum (ER) stress on muscle were tested in vitro. Serum or supernatant levels of cytokines were analyzed by multiplex immunoassay.Results
Serum MRP8/14 correlated with physician’s global assessment of disease activity in JDM (R = 0.65, p = 0.0003) and muscle strength/endurance, childhood myositis assessment score (CMAS, R = −0.55, p = 0.004). MRP8/14 was widely expressed by CD68+ macrophages in JDM muscle tissue. When cultured with human myoblasts, MRP8 led to the secretion of MCP-1 and IL-6, which was enhanced by ER stress. Both inflammatory mediators were detected in significantly higher levels in the serum of JDM patients compared to healthy controls.Conclusions
This study is the first to identify serum MRP8/14 as a potential biomarker for disease activity in JDM. We propose that tissue infiltrating macrophages secreting MRP8/14 may contribute to myositis, by driving the local production of cytokines directly from muscle. 相似文献47.
William B. Parker Sue C. Shaddix Lucy M. Rose Phuong T. Pham Mei Hua Robert Vince 《Nucleosides, nucleotides & nucleic acids》2013,32(4):795-804
Abstract The metabolism of O6-propyl-carbovir and N6-propyl-carbovir, two selective inhibitors of HIV replication, has been evaluated in CEM cells. Both compounds were phosphorylated in intact cells to carbovir-5′-triphosphate. The metabolism of these two agents was inhibited by deoxycoformycin and mycophenolic acid, but not erythro-9-(2-hydroxy-3-nonyl)adenine. No evidence of the 5′-triphosphate of either compound was detected in CEM cells. 相似文献
48.
Lucy R. Stewart Md. Ashraful Haque Mark W. Jones Margaret G. Redinbaugh 《Molecular breeding : new strategies in plant improvement》2013,31(2):289-297
Maize dwarf mosaic disease is one of the most important viral diseases of maize (Zea mays L.) throughout the world. It is caused by several virus species in the family Potyviridae, genus Potyvirus, including Maize dwarf mosaic virus (MDMV), Sugarcane mosaic virus (SCMV), Johnsongrass mosaic virus (JGMV) and Sorghum mosaic virus (SrMV). Resistance to another member of the family Potyviridae, Wheat streak mosaic virus (WSMV), is conferred by three alleles (Wsm1, Wsm2, Wsm3) in the maize inbred line Pa405, and these or closely linked genes were previously shown to confer resistance to the potyviruses MDMV and SCMV. In this study, we assessed whether Wsm alleles are linked to resistance to JGMV and SrMV. Near isogenic lines (NILs) carrying one or two of the Wsm alleles introgressed into the susceptible line Oh28 and F1 progeny from NIL × Oh28 were tested for their response to JGMV and SrMV. Our results indicate that Wsm1 provides resistance to both JGMV and SrMV in a dose-dependent manner. Wsm2 and Wsm3 each provide limited resistance, and combining Wsm alleles enhances that resistance. 相似文献
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Carly Rich Marco Geraci Lucy Griffiths Francesco Sera Carol Dezateux Mario Cortina-Borja 《PloS one》2013,8(6)