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ElFihry Raouia Elmessaoudi-Idrissi Mohcine Jadid Fatima-Zahra Zaidane Imane Chihab Hajar Tahiri Mohamed Kabine Mostafa Badre Wafaa Chemin Isabelle Marchio Agnes Pineau Pascal Ezzikouri Sayeh Benjelloun Soumaya 《中国病毒学》2020,35(5):566-574
Virologica Sinica - Hepatitis C virus (HCV) is still one of the main causes of liver disease worldwide. Metabolic disorders, including non-alcoholic fatty liver disease (NAFLD), induced by HCV have... 相似文献
76.
Marijn Bauters Sofie Meeus Matti Barthel Piet Stoffelen Hannes P. T. De Deurwaerder Flicien Meunier Travis W. Drake Quentin Ponette Jerme Ebuy Pieter Vermeir Hans Beeckman Francis wyffels Samuel Bod Hans Verbeeck Filip Vandelook Pascal Boeckx 《Global Change Biology》2020,26(8):4449-4461
Forests exhibit leaf‐ and ecosystem‐level responses to environmental changes. Specifically, rising carbon dioxide (CO2) levels over the past century are expected to have increased the intrinsic water‐use efficiency (iWUE) of tropical trees while the ecosystem is gradually pushed into progressive nutrient limitation. Due to the long‐term character of these changes, however, observational datasets to validate both paradigms are limited in space and time. In this study, we used a unique herbarium record to go back nearly a century and show that despite the rise in CO2 concentrations, iWUE has decreased in central African tropical trees in the Congo Basin. Although we find evidence that points to leaf‐level adaptation to increasing CO2—that is, increasing photosynthesis‐related nutrients and decreasing maximum stomatal conductance, a decrease in leaf δ13C clearly indicates a decreasing iWUE over time. Additionally, the stoichiometric carbon to nitrogen and nitrogen to phosphorus ratios in the leaves show no sign of progressive nutrient limitation as they have remained constant since 1938, which suggests that nutrients have not increasingly limited productivity in this biome. Altogether, the data suggest that other environmental factors, such as increasing temperature, might have negatively affected net photosynthesis and consequently downregulated the iWUE. Results from this study reveal that the second largest tropical forest on Earth has responded differently to recent environmental changes than expected, highlighting the need for further on‐ground monitoring in the Congo Basin. 相似文献
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Suzanne M. Marselis Katharine Abernethy Alfonso Alonso John Armston Timothy R. Baker Jean‐Francois Bastin Jan Bogaert Doreen S. Boyd Pascal Boeckx David F. R. P. Burslem Robin Chazdon David B. Clark David Coomes Laura Duncanson Steven Hancock Ross Hill Chris Hopkinson Elizabeth Kearsley James R. Kellner David Kenfack Nicolas Labrire Simon L. Lewis David Minor Herv Memiaghe Abel Monteagudo Reuben Nilus Michael O'Brien Oliver L. Phillips John Poulsen Hao Tang Hans Verbeeck Ralph Dubayah 《Global Ecology and Biogeography》2020,29(10):1799-1816
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Johanna Marin‐Carbonne Vincent Busigny Jennyfer Miot Claire Rollion‐Bard Elodie Muller Nadja Drabon Damien Jacob Sylvain Pont Martin Robyr Tomaso R. R. Bontognali Camille Franois Stephanie Reynaud Mark Van Zuilen Pascal Philippot 《Geobiology》2020,18(3):306-325
On the basis of phylogenetic studies and laboratory cultures, it has been proposed that the ability of microbes to metabolize iron has emerged prior to the Archaea/Bacteria split. However, no unambiguous geochemical data supporting this claim have been put forward in rocks older than 2.7–2.5 giga years (Gyr). In the present work, we report in situ Fe and S isotope composition of pyrite from 3.28‐ to 3.26‐Gyr‐old cherts from the upper Mendon Formation, South Africa. We identified three populations of microscopic pyrites showing a wide range of Fe isotope compositions, which cluster around two δ56Fe values of ?1.8‰ and +1‰. These three pyrite groups can also be distinguished based on the pyrite crystallinity and the S isotope mass‐independent signatures. One pyrite group displays poorly crystallized pyrite minerals with positive Δ33S values > +3‰, while the other groups display more variable and closer to 0‰ Δ33S values with recrystallized pyrite rims. It is worth to note that all the pyrite groups display positive Δ33S values in the pyrite core and similar trace element compositions. We therefore suggest that two of the pyrite groups have experienced late fluid circulations that have led to partial recrystallization and dilution of S isotope mass‐independent signature but not modification of the Fe isotope record. Considering the mineralogy and geochemistry of the pyrites and associated organic material, we conclude that this iron isotope systematic derives from microbial respiration of iron oxides during early diagenesis. Our data extend the geological record of dissimilatory iron reduction (DIR) back more than 560 million years (Myr) and confirm that micro‐organisms closely related to the last common ancestor had the ability to reduce Fe(III). 相似文献
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Olivo Miotto Makoto Sekihara Shin-Ichiro Tachibana Masato Yamauchi Richard D. Pearson Roberto Amato Sonia Gonalves Somya Mehra Rintis Noviyanti Jutta Marfurt Sarah Auburn Ric N. Price Ivo Mueller Mie Ikeda Toshiyuki Mori Makoto Hirai Livingstone Tavul Manuel W. Hetzel Moses Laman Alyssa E. Barry Pascal Ringwald Jun Ohashi Francis Hombhanje Dominic P. Kwiatkowski Toshihiro Mita 《PLoS pathogens》2020,16(12)
The rapid and aggressive spread of artemisinin-resistant Plasmodium falciparum carrying the C580Y mutation in the kelch13 gene is a growing threat to malaria elimination in Southeast Asia, but there is no evidence of their spread to other regions. We conducted cross-sectional surveys in 2016 and 2017 at two clinics in Wewak, Papua New Guinea (PNG) where we identified three infections caused by C580Y mutants among 239 genotyped clinical samples. One of these mutants exhibited the highest survival rate (6.8%) among all parasites surveyed in ring-stage survival assays (RSA) for artemisinin. Analyses of kelch13 flanking regions, and comparisons of deep sequencing data from 389 clinical samples from PNG, Indonesian Papua and Western Cambodia, suggested an independent origin of the Wewak C580Y mutation, showing that the mutants possess several distinctive genetic features. Identity by descent (IBD) showed that multiple portions of the mutants’ genomes share a common origin with parasites found in Indonesian Papua, comprising several mutations within genes previously associated with drug resistance, such as mdr1, ferredoxin, atg18 and pnp. These findings suggest that a P. falciparum lineage circulating on the island of New Guinea has gradually acquired a complex ensemble of variants, including kelch13 C580Y, which have affected the parasites’ drug sensitivity. This worrying development reinforces the need for increased surveillance of the evolving parasite populations on the island, to contain the spread of resistance. 相似文献
80.
Kvin Magne Shengbin Liu Sophie Massot Marion Dalmais Halima Morin Richard Sibout Abdelhafid Bendahmane Pascal Ratet 《The Plant journal : for cell and molecular biology》2020,103(2):645-659
In cultivated grasses, tillering, spike architecture and seed shattering represent major agronomical traits. In barley, maize and rice, the NOOT‐BOP‐COCH‐LIKE (NBCL) genes play important roles in development, especially in ligule development, tillering and flower identity. However, compared with dicots, the role of grass NBCL genes is underinvestigated. To better understand the role of grass NBCLs and to overcome any effects of domestication that might conceal their original functions, we studied TILLING nbcl mutants in the non‐domesticated grass Brachypodium distachyon. In B. distachyon, the NBCL genes BdUNICULME4 (CUL4) and BdLAXATUM‐A (LAXA) are orthologous, respectively, to the barley HvUniculme4 and HvLaxatum‐a, to the maize Zmtassels replace upper ears1 and Zmtassels replace upper ears2 and to the rice OsBLADE‐ON‐PETIOLE1 and OsBLADE‐ON‐PETIOLE2/3. In B. distachyon, our reverse genetics study shows that CUL4 is not essential for the establishment of the blade–sheath boundary but is necessary for the development of the ligule and auricles. We report that CUL4 also exerts a positive role in tillering and a negative role in spikelet meristem activity. On the other hand, we demonstrate that LAXA plays a negative role in tillering, positively participates in spikelet development and contributes to the control of floral organ number and identity. In this work, we functionally characterized two new NBCL genes in a context of non‐domesticated grass and highlighted original roles for grass NBCL genes that are related to important agronomical traits. 相似文献