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71.
Damien Y. Duveau Xin Hu Martin J. Walsh Suneet Shukla Amanda P. Skoumbourdis Matthew B. Boxer Suresh V. Ambudkar Min Shen Craig J. Thomas 《Bioorganic & medicinal chemistry letters》2013,23(3):682-686
The importance of the trifluoromethyl group in the polypharmacological profile of nilotinib was investigated. Molecular editing of nilotinib led to the design, synthesis and biological evaluation of analogues where the trifluoromethyl group was replaced by a proton, fluorine and a methyl group. While these analogues were less active than nilotinib toward Abl, their activity toward Kit was comparable, with the monofluorinated analogue being the most active. Docking of nilotinib and of analogues 2a–c to the binding pocket of Abl and of Kit showed that the lack of shape complementarity in Kit is compensated by the stabilizing effect from its juxtamembrane region. 相似文献
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Fine‐tuning for the tropics: application of eDNA technology for invasive fish detection in tropical freshwater ecosystems 下载免费PDF全文
Heather L. A. Robson Tansyn H. Noble Richard J. Saunders Simon K. A. Robson Damien W. Burrows Dean R. Jerry 《Molecular ecology resources》2016,16(4):922-932
Invasive species pose a major threat to aquatic ecosystems. Their impact can be particularly severe in tropical regions, like those in northern Australia, where >20 invasive fish species are recorded. In temperate regions, environmental DNA (eDNA) technology is gaining momentum as a tool to detect aquatic pests, but the technology's effectiveness has not been fully explored in tropical systems with their unique climatic challenges (i.e. high turbidity, temperatures and ultraviolet light). In this study, we modified conventional eDNA protocols for use in tropical environments using the invasive fish, Mozambique tilapia (Oreochromis mossambicus) as a detection model. We evaluated the effects of high water temperatures and fish density on the detection of tilapia eDNA, using filters with larger pores to facilitate filtration. Large‐pore filters (20 μm) were effective in filtering turbid waters and retaining sufficient eDNA, whilst achieving filtration times of 2–3 min per 2‐L sample. High water temperatures, often experienced in the tropics (23, 29, 35 °C), did not affect eDNA degradation rates, although high temperatures (35 °C) did significantly increase fish eDNA shedding rates. We established a minimum detection limit for tilapia (1 fish/0.4 megalitres/after 4 days) and found that low water flow (3.17 L/s) into ponds with high fish density (>16 fish/0.4 megalitres) did not affect eDNA detection. These results demonstrate that eDNA technology can be effectively used in tropical ecosystems to detect invasive fish species. 相似文献
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Benoit de Thoisy Hervé Bourhy Marguerite Delaval Dominique Pontier Laurent Dacheux Edith Darcissac Damien Donato Amandine Guidez Florence Larrous Rachel Lavenir Arielle Salmier Vincent Lacoste Anne Lavergne 《PLoS neglected tropical diseases》2016,10(1)
Introduction
In addition to the commonly accepted importance of the vampire bat in the maintenance and transmission of the rabies virus (RABV) in South America, RABV infection of other species is widely evidenced, challenging their role in the viral cycle.Methodology / Principles findings
To identify the bioecological drivers of RABV circulation in neotropical bat communities, we conducted a molecular and serological survey on almost 1,000 bats from 30 species, and a 4-year longitudinal survey in two colonies of vampire bats in French Guiana. RABV was molecularly detected in a common vampire and in a frugivorous bat. The sequences corresponded to haematophagous bat-related strains and were close to viruses circulating in the Brazilian Amazon region. Species’ seroprevalence ranged from 0 to 20%, and the risk of seropositivity was higher in bats with a haematophagous diet, living in monospecific colonies and in dense forests. The longitudinal survey showed substantial temporal fluctuations, with individual waves of seroconversions and waning immunity. The high prevalences observed in bat communities, in most habitats and in species that do not share the same microhabitats and bioecological patterns, the temporal variations, and a rather short period of detectable antibodies as observed in recaptured vampires suggest (i) frequent exposure of animals, (ii) an ability of the infected host to control and eliminate the virus, (iii) more relaxed modes of exposure between bats than the commonly assumed infection via direct contact with saliva of infected animals, all of which should be further investigated.Conclusions / significance
We hypothesize that RABV circulation in French Guiana is mainly maintained in the pristine forest habitats that may provide sufficient food resources to allow vampire bats, the main prevalent species, to survive and RABV to be propagated. However, on the forest edge and in disturbed areas, human activities may induce more insidious effects such as defaunation. One of the ecological consequences is the disappearance of resources for tertiary or secondary consumers. Populations of vampires may then shift to alternative resources such as cattle, domestic animals and humans. Therefore, a good forest status, allowing both a dilution effect in highly rich bat communities and the maintenance of large populations of medium-sized and large mammals used as prey by vampires, should prevent their migration to anthropized areas. 相似文献75.
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The macroecology of infectious diseases: a new perspective on global‐scale drivers of pathogen distributions and impacts 下载免费PDF全文
Patrick R. Stephens Sonia Altizer Katherine F. Smith A. Alonso Aguirre James H. Brown Sarah A. Budischak James E. Byers Tad A. Dallas T. Jonathan Davies John M. Drake Vanessa O. Ezenwa Maxwell J. Farrell John L. Gittleman Barbara A. Han Shan Huang Rebecca A. Hutchinson Pieter Johnson Charles L. Nunn David Onstad Andrew Park Gonzalo M. Vazquez‐Prokopec John P. Schmidt Robert Poulin 《Ecology letters》2016,19(9):1159-1171
Identifying drivers of infectious disease patterns and impacts at the broadest scales of organisation is one of the most crucial challenges for modern science, yet answers to many fundamental questions remain elusive. These include what factors commonly facilitate transmission of pathogens to novel host species, what drives variation in immune investment among host species, and more generally what drives global patterns of parasite diversity and distribution? Here we consider how the perspectives and tools of macroecology, a field that investigates patterns and processes at broad spatial, temporal and taxonomic scales, are expanding scientific understanding of global infectious disease ecology. In particular, emerging approaches are providing new insights about scaling properties across all living taxa, and new strategies for mapping pathogen biodiversity and infection risk. Ultimately, macroecology is establishing a framework to more accurately predict global patterns of infectious disease distribution and emergence. 相似文献
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Research on embryo donation and receipt continues to grow, highlighting how specific national contexts shape views and experiences. The present article reports on a qualitative study on embryo donation and receipt in Australia. Interviews were conducted with 15 participants: embryo donors and those seeking to donate (6), embryo recipients and those seeking donors (3), people with embryos in storage or previously in storage (5), and egg donors where resulting embryos were donated to a third party (1). A deductive thematic analysis identified four key themes: understandings of embryos as cells, potential children, and/or children; a focus on relationships between “siblings”; importance of language and “family words” in discussing relationships; and extended family members having difficulty understanding the concept of embryo donation. The article concludes with a consideration of the implications of the findings in terms of the practice of embryo donation and the policies that surround it. 相似文献