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1.
Mol Ecol ; 32(7): 1639-1655, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36626136

RESUMO

Understanding the evolutionary processes that shape the landscape of genetic variation and influence the response of species to future climate change is critical for biodiversity conservation. Here, we sampled 27 populations across the distribution range of a dominant forest tree, Quercus acutissima, in East Asia, and applied genome-wide analyses to track the evolutionary history and predict the fate of populations under future climate. We found two genetic groups (East and West) in Q. acutissima that diverged during Pliocene. We also found a heterogeneous landscape of genomic variation in this species, which may have been shaped by population demography and linked selections. Using genotype-environment association analyses, we identified climate-associated SNPs in a diverse set of genes and functional categories, indicating a model of polygenic adaptation in Q. acutissima. We further estimated three genetic offset metrics to quantify genomic vulnerability of this species to climate change due to the complex interplay between local adaptation and migration. We found that marginal populations are under higher risk of local extinction because of future climate change, and may not be able to track suitable habitats to maintain the gene-environment relationships observed under the current climate. We also detected higher reverse genetic offsets in northern China, indicating that genetic variation currently present in the whole range of Q. acutissima may not adapt to future climate conditions in this area. Overall, this study illustrates how evolutionary processes have shaped the landscape of genomic variation, and provides a comprehensive genome-wide view of climate maladaptation in Q. acutissima.


Assuntos
Mudança Climática , Quercus , Árvores , Florestas , Estudo de Associação Genômica Ampla , Genômica , Quercus/genética , Árvores/genética
2.
Pest Manag Sci ; 79(1): 105-113, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36088646

RESUMO

BACKGROUND: Plants respond to attackers by triggering phytohormones signaling associated metabolites, including herbivore-induced plant volatiles (HIPVs). HIPVs can indirectly act against herbivory by recruitment of natural enemies and priming of neighboring plants. Ostrinia furnacalis and Mythimna separata are important insect herbivores of maize plants that have a devastating influence on yield. However, little is known about how maize temporally reconfigures its defense systems against these herbivores and variation of neighboring plant resistance. RESULTS: This study investigated the effects of HIPVs on the behavior of the dominant predatory beetle Harmonia axyridis and priming in neighboring maize defense against O. furnacalis and M. separata over time. The results showed that maize damaged by either O. furnacalis or M. separata enhanced the release of volatiles including terpenes, aldehydes, alkanes and an ester, which elicited an increased attractive response to H. axyridis after 3 and 12 h, respectively. O. furnacalis damage resulted in accumulations of leaf jasmonic acid (JA) and salicylic acid in maize after 6 and 3 h, respectively, while M. separata damage only raised the JA level after 3 h. Furthermore, HIPVs were able to prime neighboring plants through the accumulation of JA after 24 h. Both larvae showed a significant decrease in weight accumulation after 48 h of feeding on the third leaves of the primed plant. CONCLUSION: Taken together, the findings provide a dynamic overview of how attacked maize reconfigures its volatiles and phytohormones to defend against herbivores, as well as priming of neighboring plants against oncoming attacks. © 2022 Society of Chemical Industry.


Assuntos
Zea mays
3.
Dermatol Ther ; 35(12): e15928, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36222320

RESUMO

This meta-analysis aimed to assess the efficacy of omalizumab in the treatment of refractory-to-antihistamines chronic induced urticaria (CIndU) in comparison with that of refractory-to-antihistamines chronic spontaneous urticaria (CSU). We retrieved interventional studies and observational studies on omalizumab efficacy to CIndU patients and efficacy comparison between CSU and CIndU both refractory to H1-antihistamines in electronic databases (accessed till May 2022). The odd ratio (OR) and 95% confidence interval (CI) was calculated with a random-effect model in this meta-analysis. The majority of patients with different CIndU subtypes gained complete or partial response and good safety after omalizumab treatment. A total of five studies with 355 CSU patients and 103 CIndU patients were included for the meta-analysis. There was no significant difference in the efficacy of omalizumab in the treatment of CSU and CIndU (OR -0.83, 95% CI [0.84, 2.21], P > 0.05). Based on the validity of omalizumab in the treatment of various CIndU subtypes and non-differential efficacy between CSU and CIndU, it is reasonable to list omalizumab as a third-line treatment of refractory CIndU.


Assuntos
Antialérgicos , Urticária Crônica , Urticária , Humanos , Omalizumab/efeitos adversos , Antialérgicos/efeitos adversos , Urticária/tratamento farmacológico , Urticária/induzido quimicamente , Doença Crônica , Urticária Crônica/tratamento farmacológico , Antagonistas dos Receptores Histamínicos/uso terapêutico , Resultado do Tratamento
4.
Nat Commun ; 13(1): 1320, 2022 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-35288565

RESUMO

Northern Hemisphere forests changed drastically in the early Eocene with the diversification of the oak family (Fagaceae). Cooling climates over the next 20 million years fostered the spread of temperate biomes that became increasingly dominated by oaks and their chestnut relatives. Here we use phylogenomic analyses of nuclear and plastid genomes to investigate the timing and pattern of major macroevolutionary events and ancient genome-wide signatures of hybridization across Fagaceae. Innovation related to seed dispersal is implicated in triggering waves of continental radiations beginning with the rapid diversification of major lineages and resulting in unparalleled transformation of forest dynamics within 15 million years following the K-Pg extinction. We detect introgression at multiple time scales, including ancient events predating the origination of genus-level diversity. As oak lineages moved into newly available temperate habitats in the early Miocene, secondary contact between previously isolated species occurred. This resulted in adaptive introgression, which may have further amplified the diversification of white oaks across Eurasia.


Assuntos
Genomas de Plastídeos , Quercus , Ecossistema , Florestas , Genomas de Plastídeos/genética , Filogenia
5.
Brain Sci ; 12(2)2022 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-35204003

RESUMO

BACKGROUND: Developmental dyslexia (DD) is a specific learning disorder concerning reading acquisition that may has a lifelong negative impact on individuals. A reliable estimate of the prevalence of DD serves as the basis for diagnosis, intervention, and evidence-based health resource allocation and policy-making. Hence, the present meta-analysis aims to generate a reliable prevalence estimate of DD worldwide in primary school children and explore the potential variables related to that prevalence. METHODS: Studies from the 1950s to June 2021 were collated using a combination of search terms related to DD and prevalence. Study quality was assessed using the STROBE guidelines according to the study design, with study heterogeneity assessed using the I2 statistic, and random-effects meta-analyses were conducted. Variations in the prevalence of DD in different subgroups were assessed via subgroup meta-analysis and meta-regression. RESULTS: The pooled prevalence of DD was 7.10% (95% CI: 6.27-7.97%). The prevalence in boys was significantly higher than that in girls (boys: 9.22%, 95%CI, 8.07-10.44%; girls: 4.66%, 95% CI, 3.84-5.54%; p < 0.001), but no significant difference was found in the prevalence across different writing systems (alphabetic scripts: 7.26%, 95%CI, 5.94-8.71%; logographic scripts: 6.97%, 95%CI, 5.86-8.16%; p > 0.05) or across different orthographic depths (shallow: 7.13%, 95% CI, 5.23-9.30%; deep: 7.55%, 95% CI, 4.66-11.04%; p > 0.05). It is worth noting that most articles had small sample sizes with diverse operational definitions, making comparisons challenging. CONCLUSIONS: This study provides an estimation of worldwide DD prevalence in primary school children. The prevalence was higher in boys than in girls but was not significantly different across different writing systems.

6.
ACS Appl Bio Mater ; 5(3): 1222-1229, 2022 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-35167266

RESUMO

The immobilization of enzymes has received much attention. Metal-organic framework (MOF) as the adsorbent for enzyme encapsulation provides an effective strategy. However, the encapsulation efficacy is not dependent solely on the specific surface area. Though leading into appropriate substrate with negative charge would enhance the encapsulation efficacy. Polyoxometalates (POMs) as the electron sponge would donate electrons without any structural change. In this study, Keggin-type phosphotungstic acid (PW12) was encapsulated in Zirconium metal-organic framework (PW12@UiO-67) as a heterogeneous adsorbent for the encapsulation of enzyme. Our following data proved that this composite cluster could enhance the adsorption of enzyme and the stability of MP-11 was then significantly improved after immobilization.


Assuntos
Estruturas Metalorgânicas , Ânions , Enzimas Imobilizadas/química , Estruturas Metalorgânicas/química , Oligopeptídeos , Polieletrólitos
7.
New Phytol ; 233(1): 555-568, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34637540

RESUMO

Natural selection shapes genome-wide patterns of diversity within species and divergence between species. However, quantifying the efficacy of selection and elucidating the relative importance of different types of selection in shaping genomic variation remain challenging. We sequenced whole genomes of 101 individuals of three closely related oak species to track the divergence history, and to dissect the impacts of selective sweeps and background selection on patterns of genomic variation. We estimated that the three species diverged around the late Neogene and experienced a bottleneck during the Pleistocene. We detected genomic regions with elevated relative differentiation ('FST -islands'). Population genetic inferences from the site frequency spectrum and ancestral recombination graph indicated that FST -islands were formed by selective sweeps. We also found extensive positive selection; the fixation of adaptive mutations and reduction neutral diversity around substitutions generated a signature of selective sweeps. Prevalent negative selection and background selection have reduced genetic diversity in both genic and intergenic regions, and contributed substantially to the baseline variation in genetic diversity. Our results demonstrate the importance of linked selection in shaping genomic variation, and illustrate how the extent and strength of different selection models vary across the genome.


Assuntos
Quercus , Variação Genética , Genética Populacional , Genoma , Genômica , Quercus/genética , Seleção Genética
8.
Dalton Trans ; 49(29): 10156-10161, 2020 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-32662802

RESUMO

Focusing on renewable energy, we are devoted to developping efficient, robust and low cost water reduction catalysts (WRCs). Two new Cu-based borate catalysts, namely H2Na2K2[(µ4-O)Cu4@B20O32(OH)8]·21H2O (1) and H2Rb1.6K2.4[(µ4-O)Cu4@B20O32 (OH)8]·15H2O (2), with cubic supramolecular cages were synthesized under a hydrothermal condition. Moreover, new copper complexes were applied as water reduction catalysts (WRCs) in the presence of [Ir(ppy)2(dtbbpy)][PF6] as photosensitizer and triethanolamine (TEOA) as the sacrificial electron donor. Nevertheless, the main active place is attributed to the centre of Borates [(µ4-O)Cu4@B20O32(OH)8], and the atomic radius of the counter cation would be the critical factor of the photocatalytic activity. Increasing the atomic radius from the Na atom to the Rb atom, causes the photocatalytic activity to decrease efficiently. The experimental results match well with the density functional theory (DFT) conclusion. It is noteworthy to mention that our research not only enriches the Cu-based borate chemistry, but also investigates the photocatalytic activity of Cu-based borates. This would guide us through the borate synthesis and to develop their applications toward energy and the environment.

9.
J Hazard Mater ; 310: 56-67, 2016 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-26897575

RESUMO

Quorum sensing inhibitors (QSIs) are considered to be promising antibiotic alternatives and will be increasingly exposed to the environment together with antibiotics after their research and development process; it is therefore necessary to study the joint effects of QSIs and antibiotics. In this study, single and mixed toxicity of sulfonamide (SAs) and QSIs under acute and chronic conditions and their corresponding toxicity mechanisms were investigated. The results indicated that the acute joint effect was extremely complex, ranging from an antagonistic to synergistic response, while the chronic joint effect was primarily an antagonistic response. Using a molecular docking and regression model, we found that the acute joint effect could be determined by the hydrion's, ability to be oxidized, as well as the binding energy. The chronic joint effect was primarily an antagonistic response, which was due to the QSI competing against AHL for luxR generated by SAs, leading to negative effects of the QSI-luxR complexes on luxI. This phenomenon eventually weakened the stimulatory effect caused by SAs. Finally, the main differences between acute and chronic mixtures were analyzed: (1) The target protein was different between acute and chronic toxicity mixtures, and (2) effective concentration in acute and chronic toxicity mixtures was also different. These deep insights into mixed toxicity mechanisms will play an important role in the study of antibiotic resistance genes in response to antibiotic replacements.


Assuntos
Aliivibrio fischeri/efeitos dos fármacos , Antibacterianos/toxicidade , Percepção de Quorum/efeitos dos fármacos , Sulfonamidas/toxicidade , Proteínas de Bactérias/metabolismo , Modelos Moleculares , Proteínas Repressoras/metabolismo , Transativadores/metabolismo
10.
Chemosphere ; 150: 159-167, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26901472

RESUMO

The 50% effect level of a single chemical in the real environment is almost impossible to determine at the low exposure concentration, and the prediction of the concentration of a mixture at the 50% effect level from the concentration of a single chemical at the low effect level is even more difficult. The current literature does not address this problem. Thus, to determine solutions for this question, single/mixture chronic toxicities of sulfonamides (SAs) and quorum-sensing inhibitors (QSIs) were determined using Gram-negative bacteria (Vibrio fischeri and E. coli.) and Gram-positive bacteria (B. subtilis) as the target organisms. The results showed that the joint effects of SAs and QSIs were primarily antagonistic responses. In addition, the toxicity mechanisms of mixtures of SAs and QSIs were investigated further, and the results revealed that the chronic joint effects were primarily an antagonistic response due to the QSI competing against acyl-homoserine lactones (AHL) for luxR in V. fischeri and SdiA in E. coli generated by the SAs, leading to negative effects exerted by the QSI-luxR or QSI-SdiA complexes on luxI in V. fischeri or FtsZ in E. coli. This phenomenon eventually weakened the stimulatory effect caused by the SAs. Based on the mixture toxicity mechanism, the relationship between the mixture toxicity and the simulation effect was formulated.


Assuntos
Antibacterianos/toxicidade , Poluentes Ambientais/toxicidade , Bactérias Gram-Negativas/efeitos dos fármacos , Hormese/efeitos dos fármacos , Percepção de Quorum/efeitos dos fármacos , Sulfonamidas/toxicidade , Aliivibrio fischeri/efeitos dos fármacos , Antibacterianos/química , Bacillus subtilis/efeitos dos fármacos , Proteínas de Bactérias/química , Antagonismo de Drogas , Sinergismo Farmacológico , Poluentes Ambientais/química , Escherichia coli/efeitos dos fármacos , Simulação de Acoplamento Molecular , Relação Quantitativa Estrutura-Atividade , Sulfonamidas/química , Testes de Toxicidade Crônica , Transativadores/química
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