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61.
Scott Klasek Marta E. Torres Douglas H. Bartlett Madeline Tyler Wei-Li Hong Frederick Colwell 《Environmental microbiology》2020,22(5):1829-1846
Anaerobic methanotrophic archaea (ANME) consume methane in marine sediments, limiting its release to the water column, but their responses to changes in methane and sulfate supplies remain poorly constrained. To address how methane exposure may affect microbial communities and methane- and sulfur-cycling gene abundances in Arctic marine sediments, we collected sediments from offshore Svalbard that represent geochemical horizons where anaerobic methanotrophy is expected to be active, previously active, and long-inactive based on reaction-transport biogeochemical modelling of porewater sulfate profiles. Sediment slurries were incubated at in situ temperature and pressure with different added methane concentrations. Sediments from an active area of seepage began to reduce sulfate in a methane-dependent manner within months, preceding increased relative abundances of anaerobic methanotrophs ANME-1 within communities. In previously active and long-inactive sediments, sulfur-cycling Deltaproteobacteria became more dominant after 30 days, though these communities showed no evidence of methanotrophy after nearly 8 months of enrichment. Overall, enrichment conditions, but not methane, broadly altered microbial community structure across different enrichment times and sediment types. These results suggest that active ANME populations may require years to develop, and consequently microbial community composition may affect methanotrophic responses to potential large-scale seafloor methane releases in ways that provide insight for future modelling studies. 相似文献
62.
Daniele Novarina Georges E. Janssens Koen Bokern Tim Schut Noor C. van Oerle Hinke G. Kazemier Liesbeth M. Veenhoff Michael Chang 《Aging cell》2020,19(2)
To ensure proper transmission of genetic information, cells need to preserve and faithfully replicate their genome, and failure to do so leads to genome instability, a hallmark of both cancer and aging. Defects in genes involved in guarding genome stability cause several human progeroid syndromes, and an age‐dependent accumulation of mutations has been observed in different organisms, from yeast to mammals. However, it is unclear whether the spontaneous mutation rate changes during aging and whether specific pathways are important for genome maintenance in old cells. We developed a high‐throughput replica‐pinning approach to screen for genes important to suppress the accumulation of spontaneous mutations during yeast replicative aging. We found 13 known mutation suppression genes, and 31 genes that had no previous link to spontaneous mutagenesis, and all acted independently of age. Importantly, we identified PEX19, encoding an evolutionarily conserved peroxisome biogenesis factor, as an age‐specific mutation suppression gene. While wild‐type and pex19Δ young cells have similar spontaneous mutation rates, aged cells lacking PEX19 display an elevated mutation rate. This finding suggests that functional peroxisomes may be important to preserve genome integrity specifically in old cells. 相似文献
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dos Santos Fernanda Marcelia Pflüger Pricila Fernandes Lazzarotto Leticia Uczay Mariana de Aguida Wesley Roberto da Silva Lisiane Santos Boaretto Fernanda Brião Menezes de Sousa Jayne Torres Picada Jaqueline Nascimento da Silva Torres Iraci Lucena Pereira Patrícia 《Neurochemical research》2021,46(8):2066-2078
Neurochemical Research - Gamma-decanolactone (GD) has been shown to reduce epileptic behavior in different models, inflammatory decreasing, oxidative stress, and genotoxic parameters. This study... 相似文献
65.
de Sousa Sylvia Morais de Oliveira Christiane Abreu Andrade Daniele Luiz de Carvalho Chainheny Gomes Ribeiro Vitória Palhares Pastina Maria Marta Marriel Ivanildo Evódio de Paula Lana Ubiraci Gomes Gomes Eliane Aparecida 《Journal of Plant Growth Regulation》2021,40(2):867-877
Journal of Plant Growth Regulation - The rising demand for agricultural commodities in developing countries has put increasing pressure on land resources for higher yields, with associated growth... 相似文献
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Alberto Cornejo Julio Caballero Mario Simirgiotis Vanessa Torres Luisa Snchez Nicols Díaz Marcela Guimaraes Marcos Hernndez Carlos Areche Sergio Alfaro Leonardo Caballero Francisco Melo 《Journal of enzyme inhibition and medicinal chemistry》2021,36(1):154
Parkinson''s disease (PD) is a neurodegenerative disorder that affects adult people whose treatment is palliative. Thus, we decided to test three dammarane triterpenes 1, 1a, 1b, and we determined that 1 and 1a inhibit β-aggregation through thioflavine T rather than 1b. Since compound 1 was most active, we determined the interaction between α-synuclein and 1 at 50 µM (Kd) through microscale thermophoresis. Also, we observed differences in height and diameter of aggregates, and α-synuclein remains unfolded in the presence of 1. Also, aggregates treated with 1 do not provoke neurites'' retraction in N2a cells previously induced by retinoic acid. Finally, we studied the potential sites of interaction between 1 with α-synuclein fibrils using molecular modelling. Docking experiments suggest that 1 preferably interact with the site 2 of α-synuclein through hydrogen bonds with residues Y39 and T44. 相似文献
69.
Agna R.S. Rodrigues Jorge B. Torres Herbert A.A. Siqueira Daniel P.A. Lacerda 《Biological Control》2013,64(3):217-224
Lambda-cyhalothrin is a pyrethroid insecticide widely used to control pests in various crop ecosystems, in which the lady beetle occurs naturally. Therefore, lady beetle populations are exposed to lambda-cyhalothrin sprays that may foster tolerance to this insecticide. This study was conducted to confirm the occurrence of resistance in the lady beetle Eriopis connexa (Germar) (Coleoptera: Coccinellidae) to lambda-cyhalothrin and to characterize the inheritance of resistance after eight progressive selection with insecticide dosages based on the LD50 determined for the F1 generation. Dose–mortality curves were determined for parental populations, F1 hybrids and backcross progenies. Parameters regarding the heritability of resistance to lambda-cyhalothrin in E. connexa allow estimating 10-fold increase in the initial LD50 after 54.5 generations of successive selections. The resistance of E. connexa to lambda-cyhalothrin was characterized as autosomally inherited and incompletely dominant, and influenced by a major gene with possible influence of secondary genes. Additionally, the resistance in E. connexa varies from functionally dominant to functionally recessive depending on the dose used. These findings indicate that insecticide resistance in E. connexa can be selected in the field as determined for field-collected individuals, and subsequently enhanced under laboratory conditions. Its characterization presented here is an important step toward linking biological and chemical control within pest management regarding the lady beetle and lambda-cyhalothrin targeting different pest groups. 相似文献
70.
Matthew Oldfield Daniele Dini Gianpaolo Giordano Ferdinando Rodriguez y Baena 《Computer methods in biomechanics and biomedical engineering》2013,16(5):530-543
Detailed finite element modelling of needle insertions into soft tissue phantoms encounters difficulties of large deformations, high friction, contact loading and material failure. This paper demonstrates the use of cohesive elements in high-resolution finite element models to overcome some of the issues associated with these factors. Experiments are presented enabling extraction of the strain energy release rate during crack formation. Using data from these experiments, cohesive elements are calibrated and then implemented in models for validation of the needle insertion process. Successful modelling enables direct comparison of finite element and experimental force–displacement plots and energy distributions. Regions of crack creation, relaxation, cutting and full penetration are identified. By closing the loop between experiments and detailed finite element modelling, a methodology is established which will enable design modifications of a soft tissue probe that steers through complex mechanical interactions with the surrounding material. 相似文献