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971.
972.
Agnieszka M. Szemiel Andres Merits Richard J. Orton Oscar A. MacLean Rute Maria Pinto Arthur Wickenhagen Gauthier Lieber Matthew L. Turnbull Sainan Wang Wilhelm Furnon Nicolas M. Suarez Daniel Mair Ana da Silva Filipe Brian J. Willett Sam J. Wilson Arvind H. Patel Emma C. Thomson Massimo Palmarini Alain Kohl Meredith E. Stewart 《PLoS pathogens》2021,17(9)
Remdesivir (RDV), a broadly acting nucleoside analogue, is the only FDA approved small molecule antiviral for the treatment of COVID-19 patients. To date, there are no reports identifying SARS-CoV-2 RDV resistance in patients, animal models or in vitro. Here, we selected drug-resistant viral populations by serially passaging SARS-CoV-2 in vitro in the presence of RDV. Using high throughput sequencing, we identified a single mutation in RNA-dependent RNA polymerase (NSP12) at a residue conserved among all coronaviruses in two independently evolved populations displaying decreased RDV sensitivity. Introduction of the NSP12 E802D mutation into our SARS-CoV-2 reverse genetics backbone confirmed its role in decreasing RDV sensitivity in vitro. Substitution of E802 did not affect viral replication or activity of an alternate nucleoside analogue (EIDD2801) but did affect virus fitness in a competition assay. Analysis of the globally circulating SARS-CoV-2 variants (>800,000 sequences) showed no evidence of widespread transmission of RDV-resistant mutants. Surprisingly, we observed an excess of substitutions in spike at corresponding sites identified in the emerging SARS-CoV-2 variants of concern (i.e., H69, E484, N501, H655) indicating that they can arise in vitro in the absence of immune selection. The identification and characterisation of a drug resistant signature within the SARS-CoV-2 genome has implications for clinical management and virus surveillance. 相似文献
973.
Vitamin C modulates glutamate transport and NMDA receptor function in the retina 总被引:1,自引:0,他引:1 下载免费PDF全文
Ivan Domith Renato Socodato Camila C. Portugal Andressa F. Munis Aline T. Duarte‐Silva Roberto Paes‐de‐Carvalho 《Journal of neurochemistry》2018,144(4):408-420
974.
Behavioural response of Lucilia sericata to a decaying body infested by necrophagous insects 下载免费PDF全文
Numerous insect species are necrophagous, with Dipterans and Coleopterans being the most abundant on a corpse. Whether the presence of necrophageous species on a corpse affects the attraction of adult blowflies to the corpse is sparsely studied. We test the hypothesis that Lucilia sericata can discriminate the odour of a noncolonized cadaver from the odour of a cadaver on which conspecific and/or heterospecific necrophagous insects are feeding. The volatile organic compounds are collected from decomposing rats under four modalities: (i) in the absence of insects; (ii) in the presence of L. sericata adults; (iii) in the presence of Dermestes frischii adults; (iv) and in the presence of both D. frischii adults and L. sericata adults. During a multiple‐choice bioassay, blowflies are exposed to the four odour samples, and are shown to prefer the odour of a corpse where conspecific larvae are present. We also expect blowflies to avoid cadavers on which predators where present, although L. sericata are not repulsed by the odour of a cadaver colonized by hide beetles. We then compare the average quantities of all 61 volatile molecules identified, finding that the presence of necrophagous insects impacts some of them. However, none of the volatile organic compounds previously reported in the literature as being attractive for L. sericata adults are impacted by the presence of necrophagous insects. The results of the present study suggest that blowfly larvae modify the volatilome of a corpse, enabling adults to discriminate a colonized from a noncolonized corpse. 相似文献
975.
Patrícia Maria Pinto Poliana Cristina Spricigo Simone Rodrigues da Silva Steven Alonzo Sargent Angelo Pedro Jacomino 《Acta Physiologiae Plantarum》2018,40(12):205
Camu–camu, a native fruit from the Amazon region, is a rich source of bioactive compounds. However, its intense metabolic activity and high-water content limit the fruit’s postharvest storage and marketing. The aim of this study, conducted in two parts, was to evaluate the effects of 1-MCP and storage temperature on the physiology and postharvest preservation of camu–camu fruit. In part 1 of the study, fruit harvested at maturity stage 3 were divided into groups: control, 1-methylcyclopropene (1-MCP; 900 nL L?1; 12 h) and ethylene (1000 µL L?1; 24 h) and were stored at 22?±?1 °C and 85?±?5% RH for 9 days. In part 2, fruit harvested at maturity stage 3 were stored at 5, 10, 15, 20, or 25?±?1 °C and 85?±?5% RH for 9 days. During storage, fruit were evaluated daily for decay, mass loss, respiratory activity, and ethylene production, and every 3 days they were evaluated for peel color, pulp firmness, soluble solids content, total titratable acidity, ascorbic acid, total chlorophyll, and total anthocyanins. Fruit treated with 1-MCP exhibited delayed ripening due to lower metabolic activity, as evidenced by delay to softening, reduced mass loss and no decay. Storage at 5 °C prevented ethylene production, mass loss, color changes, and maintained pulp firmness, while did not affect soluble solids content. The results indicated that storage of camu–camu fruit at 5 °C or at 25 °C following application of 900 nL L?1 1-MCP were effective strategies to delay ripening and maintain fruit quality up to 9 days. 相似文献
976.
Michelli F. Santos Isis G. B. Souza Sulimary O. Gomes Geice R. Silva Paul Bentzen Fabio M. Diniz 《Journal of genetics》2018,97(1):25-33
Okra’s (Abelmoschus esculentus (L.) Moench) commercial cultivation is threatened in the tropics due to high incidence of yellow vein mosaic virus (YVMV) disease. Okra geneticists across the world tried to understand the inheritance pattern of YVMV disease tolerance without much success. Therefore, the inheritance pattern of YVMV disease in okra was revisited by employing six generations (\(\hbox {P}_{1}\), \(\hbox {P}_{2}\), \(\hbox {F}_{1}\), \(\hbox {F}_{2}\), \(\hbox {BC}_{1}\) and \(\hbox {BC}_{2}\)) of four selected crosses (one tolerant \(\times \) tolerant, two tolerant \(\times \) susceptible and one susceptible \(\times \) susceptible) using two tolerant (BCO-1 and Lal Bhendi) and two susceptible (Japanese Jhar Bhendi and PAN 2127) genotypes. Qualitative genetic analysis was done on the basis of segregation pattern of tolerant and susceptible plants in \(\hbox {F}_{2}\) and backcross generations of all the four crosses. It revealed that a single dominant gene along with some minor factors governed the disease tolerant trait in both the tolerant parents used. However, it was observed that genes governing disease tolerance identified in both the tolerant variety used was different. It could be concluded that the gene governing YVMV disease tolerance in okra was genotype specific. Further, duplicate gene action as evident from an approximate ratio of 15 : 1 (tolerant : susceptible) in the \(\hbox {F}_{2}\) population in the cross of two tolerant varieties gave a scope of increasing the tolerance level of the hybrid plants when both the tolerant genes are brought together. However, generation mean analysis revealed involvement of both additive and nonadditive effects in the inheritance of disease tolerance. Thus, the present study confirms that a complicated genetic inheritance pattern is involved in the disease tolerance against YVMV trait. The major tolerance genes could be transferred to other okra varieties, but the tolerance breaking virus strains might not allow them to achieve tolerance in stable condition. Therefore, accumulation of additional genes may be needed for a sustainable tolerance phenotype in okra. 相似文献
977.
Ines Pires da Silva Isabella C. Glitza Lauren E. Haydu Romany Johnpulle Patricia D. Banks George D. Grass Simone M. A. Goldinger Jessica L. Smith Ashlyn S. Everett Peter Koelblinger Rachel Roberts‐Thomson Michael Millward Victoria G. Atkinson Alexander Guminski Rony Kapoor Robert M. Conry Matteo S. Carlino Wei Wang Mark J. Shackleton Zeynep Eroglu Serigne Lo Angela M. Hong Georgina V. Long Douglas B. Johnson Alexander M. Menzies 《Pigment cell & melanoma research》2019,32(4):553-563
978.
Funck Graciele Daiana de Lima Marques Juliana da Silva Dannenberg Guilherme dos Santos Cruxen Claudio Eduardo Sehn Carla Pohl Prigol Marina Silva Márcia Rósula Poetini da Silva Wladimir Padilha Fiorentini Ângela Maria 《Probiotics and antimicrobial proteins》2020,12(1):91-101
Probiotics and Antimicrobial Proteins - This study aimed to characterize, evaluate toxicity and optimize the conditions for the growth and production of bacteriocin-like substances by Lactobacillus... 相似文献
979.
Xiaoning Han Michael Chen Fushun Wang Martha Windrem Su Wang Steven Shanz Qiwu Xu Nancy Ann Oberheim Lane Bekar Sarah Betstadt Alcino J. Silva Takahiro Takano Steven A. Goldman Maiken Nedergaard 《Cell Stem Cell》2013,12(3):342-353
Download : Download video (32MB) 相似文献
980.
Jih-Pai Lin Samuel M. Gon III James G. Gehling Loren E. Babcock Yuan-Long Zhao Xing-Liang Zhang 《Historical Biology》2013,25(1):33-45
Constraining the origin of animal groups is allowed, to some extent, by discoveries of Cambrian Lagerstätten that preserve both mineralizing and nonmineralizing organisms. A new species is reported here of the Cambrian arthropod Skania, which bears an exoskeleton that shares homologies with the Neoproterozoic (Ediacaran) organism Parvancorina and firmly establishes a Precambrian root for arthropods. A new monophyletic group, Parvancorinomorpha, is proposed as the first clade within the arthropod crown group demonstrably ranging across the Neoproterozoic–Paleozoic transition. The Parvancorinomorpha is interpreted to be the sister group of the Arachnomorpha. Incipient cephalization in Skania and related genera represents a step in the progression toward division of a cephalon from a large posterior trunk as shown in Cambrian arachnomorphs such as naraoiids and the addition of a pygidium and thoracic tergites as shown in the arachnomorph clade basal to trilobites. This evidence can serve as a new calibration point for estimating the divergence time for the last common ancestor of arthropods and priapulids based on molecular clock methods. 相似文献