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101.
Emma B. Hodcroft Robert Dyrdak Cristina Andrs Adrian Egli Josiane Reist Diego García Martínez de Artola Julia Alcoba-Flrez Hubert G. M. Niesters Andrs Antn Randy Poelman Marijke Reynders Elke Wollants Richard A. Neher Jan Albert 《PLoS pathogens》2022,18(5)
Worldwide outbreaks of enterovirus D68 (EV-D68) in 2014 and 2016 have caused serious respiratory and neurological disease. We collected samples from several European countries during the 2018 outbreak and determined 53 near full-length genome (‘whole genome’) sequences. These sequences were combined with 718 whole genome and 1,987 VP1-gene publicly available sequences. In 2018, circulating strains clustered into multiple subgroups in the B3 and A2 subclades, with different phylogenetic origins. Clusters in subclade B3 emerged from strains circulating primarily in the US and Europe in 2016, though some had deeper roots linking to Asian strains, while clusters in A2 traced back to strains detected in East Asia in 2015-2016. In 2018, all sequences from the USA formed a distinct subgroup, containing only three non-US samples. Alongside the varied origins of seasonal strains, we found that diversification of these variants begins up to 18 months prior to the first diagnostic detection during a EV-D68 season. EV-D68 displays strong signs of continuous antigenic evolution and all 2018 A2 strains had novel patterns in the putative neutralizing epitopes in the BC- and DE-loops. The pattern in the BC-loop of the USA B3 subgroup had not been detected on that continent before. Patients with EV-D68 in subclade A2 were significantly older than patients with a B3 subclade virus. In contrast to other subclades, the age distribution of A2 is distinctly bimodal and was found primarily among children and in the elderly. We hypothesize that EV-D68’s rapid evolution of surface proteins, extensive diversity, and high rate of geographic mixing could be explained by substantial reinfection of adults. Better understanding of evolution and immunity across diverse viral pathogens, including EV-D68 and SARS-CoV-2, is critical to pandemic preparedness in the future. 相似文献
102.
Pau-Roblot C Petit E Sarazin C Courtois J Courtois B Barbotin JN Séguin JP 《Biopolymers》2002,64(1):34-43
Partially acetylated, high molecular weight glucuronans were produced by a Sinorhizobium meliloti mutant strain. Two native glucuronan samples with various degrees of acetylation were sonicated to obtain lower molecular weight samples and with low viscosity suitable for chemical modification and (13)C NMR experiments. The average degree of substitution (DS) of the polymer was estimated by Fourier transform infrared (FTIR) and NMR. (13)C NMR spectra were obtained and used to suggest a complete assignment of the signals. The nuclear Overhauser effect spectroscopy (NOESY) and heteronuclear multi-bond coherence (HMBC) experiments were used to elucidate connectivities between the various residues and deduce the linkage of these residues within the polysaccharide. 相似文献
103.
Carotenoids modulate the trade-off between egg production and resistance to oxidative stress in zebra finches 总被引:4,自引:0,他引:4
The allocation of resources to reproduction and survival is a central question of studies of life history evolution. Usually,
increased allocation to current reproduction is paid in terms of reduced future reproduction and/or decreased survival. However,
the proximal mechanisms underlying the cost of reproduction are poorly understood. Recently, it has been shown that increased
susceptibility to oxidative stress might be one of such proximate links between reproduction and self-maintenance. Organisms
possess a range of antioxidant defenses, including endogenously produced molecules (e.g., enzymes) and compounds ingested
with food (e.g., carotenoids). If reproductive effort increases the production of reactive oxygen species, the availability
of antioxidant defenses may partly or fully counteract the free-radical damages. One could, therefore, expect that the trade-off
between reproduction and oxidative stress is modulated by the availability of antioxidant defenses. We tested this hypothesis
in zebra finches. We manipulated reproductive effort by either allowing or preventing pairs to breed. Within each breeding
or non-breeding group, the availability of antioxidant compounds was manipulated by supplementing or not supplementing the
drinking water with carotenoids. We found that although birds in the breeding and non-breeding groups did not differ in their
resistance to oxidative stress (the breakdown of red blood cells submitted to a controlled free-radical attack), one aspect
of breeding effort (i.e., the number of eggs laid by birds in both breeding and non-breeding groups) was negatively correlated
with resistance to oxidative stress only in birds that did not benefit from a carotenoid-supplemented diet. This result therefore
suggests that carotenoid availability can modulate the trade-off between reproduction and resistance to oxidative stress. 相似文献
104.
Gabriela Viegas Haute Carolina Luft Géssica Luana Antunes Josiane Silva Silveira Bruno de Souza Basso Mariana Severo da Costa Vitor Giancarlo Schneider Levorse Daniela Benvenutti Kaiber Márcio Vinícius Fagundes Donadio Jordi Gracia-Sancho Jarbas Rodrigues de Oliveira 《Journal of cellular physiology》2020,235(9):6073-6084
Acute lung injury (ALI) is an inflammatory process, and has high incidence and mortality. ALI and the acute respiratory distress syndrome are two common complications worldwide that result in acute lung failure, sepsis, and death. Pro-inflammatory substances, such as cytokines and chemokines, are responsible for activating the body's defense mechanisms and usually mediate inflammatory processes. Therefore, the research of substances that decrease the uncontrolled response of organism is seen as potential for patients with ALI. Octyl gallate (OG) is a phenolic compound with therapeutic actions namely antimicrobial, antiviral, and antifungal. In this study, we evaluated its action on lipopolysaccharide (LPS)-activated alveolar macrophages RAW 264.7 cells and ALI in male mice. Our results demonstrated protective effects of OG in alveolar macrophages activated with LPS and mice with ALI. The OG treatment significantly decreased the inflammatory markers in both studies in vitro and in vivo. The data suggested that OG can act as an anti-inflammatory agent for ALI. 相似文献
105.
Daniel Rodrigues Blanco Marcelo Ricardo Vicari Roberto Laridondo Lui Roberto Ferreira Artoni Mara Cristina de Almeida Josiane Baccarin Traldi Vladimir Pavan Margarido Orlando Moreira-Filho 《Genetica》2014,142(2):119-126
Harttia is a genus in the subfamily Loricariinae that accommodates fishes popularly known as armored catfishes. They show extensive karyotypic diversity regarding interspecific numerical/structural variation of the karyotypes, with the presence of the XX/XY1Y2 multiple sex chromosome system, as found in H. carvalhoi. In this context, this study aimed to characterize Harttia punctata chromosomally, for the first time, and to infer the rearrangements that originated the X1X1X2X2/X1X2Y multiple sex chromosome system present in this species. The data obtained in this study, with classical (Giemsa, C-banding and AgNORs) and molecular methodologies (fluorescence in situ hybridization) and chromosome microdissection, indicated that a translocation between distinct acrocentric chromosomes bearing rRNA genes, accompanied by deletions in both chromosomes, might have originated the neo-Y chromosome in this species. The data also suggest that the multiple sex chromosome systems present in H. carvalhoi and H. punctata had an independent origin, evidencing the recurrence of chromosome alterations in species from this genus. 相似文献
106.
Josiane Ribolli Cláudio Manoel Rodrigues de Melo Evoy Zaniboni-Filho 《Genetics and molecular biology》2012,35(4):761-769
Freshwater fish present unique challenges when one attempts to understand the factors that determine the structure of their populations. Habitat fragmentation is a leading cause of population decline that threatens ecosystems worldwide. In this study, we investigated the conservation status of genetic variability in the Neotropical catfish (Pimelodus maculatus). Specifically, we examined the structure and genetic diversity of this species in a region of the Upper Uruguay River fragmented by natural barriers and dams. There was no genetic structure among the four sites analyzed, indicating the existence of only one population group. A combination of environmental management and genetic monitoring should be used to minimize the impact of impoundment on panmitic populations of migratory fish species. 相似文献
107.
Gakovic M Ragimbeau J Francois V Constantinescu SN Pellegrini S 《The Journal of biological chemistry》2008,283(27):18522-18529
Tyk2 is a Jak family member involved in cytokine signaling through heterodimeric-type receptors. Here, we analyzed the impact of the Val(678)-to-Phe substitution on Tyk2 functioning. This mutation is homologous to the Jak2 Val(617)-to-Phe mutation, implicated in myeloproliferative disorders. We studied ligand-independent and ligand-dependent Jak/Stat signaling in cells expressing Tyk2 V678F. Moreover, the effect of Tyk2 V678F was monitored in the context of the native heterodimeric interferon alpha receptor and in the context of a homodimeric receptor chimera, EpoR/R1, containing the ectodomain of the erythropoietin receptor. We show that Tyk2 V678F has increased catalytic potential in vivo and in vitro and more so when it is anchored to the homodimeric receptor. Tyk2 V678F leads to constitutive Stat3 phosphorylation but has no notable effect on the canonical interferon alpha-induced signaling. However, if anchored to the homodimeric EpoR/R1, the mutant confers to the cell increased sensitivity to erythropoietin. Thus, despite the catalytic gain of function of Tyk2 V678F, the effect on ligand-induced signaling is manifest only when two mutant enzymes are juxtaposed via the homodimeric receptor. 相似文献
108.
Costa JC Neves JS de Souza MV Siqueira RA Romeiro NC Boechat N e Silva PM Martins MA 《Bioorganic & medicinal chemistry letters》2008,18(3):1162-1166
The present structure-activity relationship (SAR) study focused on chemical modifications of the structure of the local anesthetic lidocaine, and indicated analogues having reduced anesthetic potency, but with superior potency relative to the prototype in preventing anaphylactic or histamine-evoked ileum contraction. From the SAR analysis, 2-(diethylamino)-N-(trifluoromethyl-phenyl) and 2-(diethylamino)-N-(dimethyl-phenyl) acetamides were selected as the most promising compounds. New insights into the applicability of non-anesthetic lidocaine derivatives as templates in drug discovery for allergic syndromes are provided. 相似文献
109.
Yang C Mwaikambo BR Zhu T Gagnon C Lafleur J Seshadri S Lachapelle P Lavoie JC Chemtob S Hardy P 《American journal of physiology. Regulatory, integrative and comparative physiology》2008,294(2):R467-R476
Recent studies have demonstrated that lymphocyte-derived microparticles (LMPs) impair endothelial cell function. However, no data currently exist regarding the contribution of LMPs in the regulation of angiogenesis. In the present study, we investigated the effects of LMPs on angiogenesis in vivo and in vitro and demonstrated that LMPs strongly suppressed aortic ring microvessel sprouting and in vivo corneal neovascularization. In vitro, LMPs considerably diminished human umbilical vein endothelial cell survival and proliferation in a concentration-dependent manner. Mechanistically, the antioxidants U-74389G and U-83836E were partially protective against the antiproliferative effects of LMPs, whereas the NADPH oxidase (NOX) inhibitors apocynin and diphenyleneiodonium significantly abrogated these effects. Moreover, LMPs increased not only the expression of the NOX subunits gp91(phox), p22(phox), and p47(phox), but also the production of ROS and NOX-derived superoxide (O(2)(-)). Importantly, LMPs caused a pronounced augmentation in the protein expression of the CD36 antiangiogenic receptor while significantly downregulating the protein levels of VEGF receptor type 2 and its downstream signaling mediator, phosphorylated ERK1/2. In summary, LMPs potently suppress neovascularization in vivo and in vitro by augmenting ROS generation via NOX and interfering with the VEGF signaling pathway. 相似文献
110.
De Caro J Eydoux C Chérif S Lebrun R Gargouri Y Carrière F De Caro A 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》2008,151(1):1-9
Birds maintain higher plasma glucose concentrations (P(Glu)) than other vertebrates of similar body mass and, in most cases, appear to store comparatively very little glucose intracellularly as glycogen. In general, birds are insensitive to the regulation of P(Glu) by insulin. However, there appears to be no phylogenetic or dietary pattern in the avian response to exogenous insulin. Moreover, the high levels of P(Glu) do not appear to lead to significant oxidative stress as birds are longer-lived compared to mammals. Glucose is absorbed by the avian gastrointestinal tract by sodium-glucose co-transporters (SGLTs; apical side of cells) and glucose transport proteins (GLUTs; basolateral side of cells). In the kidney, both types of glucose transporters appear to be upregulated as no glucose appears in the urine. Data also indicate that the avian nervous system utilizes glucose as a metabolic substrate. In this review, we have attempted to bring together information from a variety of sources to portray how glucose serves as a metabolic substrate for birds by considering each organ system involved in glucose homeostasis. 相似文献