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1.
Brain Behav ; 14(10): e70051, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39350628

RESUMO

BACKGROUND: Epilepsy, a complex neurological disorder, is closely linked with structural and functional irregularities in the brain. However, the causal relationship between brain imaging-derived phenotypes (IDPs) and epilepsy remains unclear. This study aimed to investigate this relationship by employing a two-sample bidirectional Mendelian randomization (MR) approach. METHODS: The analysis involved 3935 cerebral IDPs from the UK Biobank and all documented cases of epilepsy (all epilepsies) cohorts from the International League Against Epilepsy, with further validation through replication and meta-analyses using epilepsy Genome-Wide Association Studies datasets from the FinnGen database. Additionally, a multivariate MR analysis framework was utilized to assess the direct impact of IDPs on all epilepsies. Furthermore, we performed a bidirectional MR analysis to investigate the relationship between the IDPs identified in all epilepsies and the 15 specific subtypes of epilepsy. RESULTS: The study identified significant causal links between four IDPs and epilepsy risk. Decreased fractional anisotropy in the left inferior longitudinal fasciculus was associated with a higher risk of epilepsy (odds ratio [OR]: 0.89, p = 3.31×10-5). Conversely, increased mean L1 in the left posterior thalamic radiation (PTR) was independently associated with a heightened epilepsy risk (OR: 1.14, p = 4.72×10-5). Elevated L3 in the left cingulate gyrus was also linked to an increased risk (OR: 1.09, p = .03), while decreased intracellular volume fraction in the corpus callosum was correlated with higher epilepsy risk (OR: 0.94, p = 1.15×10-4). Subtype analysis revealed that three of these IDPs are primarily associated with focal epilepsy (FE). Notably, increased L1 in the left PTR was linked to an elevated risk of hippocampal sclerosis (HS) and lesion-negative FE, whereas elevated L3 in the left cingulate gyrus was associated with HS-related FE. CONCLUSIONS: Our research offers genetic evidence for a causal link between brain IDPs and epilepsy. These results enhance our understanding of the structural brain changes associated with the onset and progression of epilepsy.


Assuntos
Epilepsia , Análise da Randomização Mendeliana , Humanos , Epilepsia/genética , Epilepsia/diagnóstico por imagem , Epilepsia/fisiopatologia , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Estudo de Associação Genômica Ampla , Imageamento por Ressonância Magnética , Masculino , Feminino , Fenótipo , Neuroimagem/métodos , Adulto , Pessoa de Meia-Idade
2.
ChemSusChem ; : e202401552, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39135510

RESUMO

Fe single atoms (Fe SAs) based catalysts have received much attention in electrocatalytic oxygen reduction reaction (ORR) due to its low-cost and high activity. Yet, the facile synthesis of efficient and stable Fe SAs catalysts are still challenging. Here, we reported a Fe SAs anchored on N-doped mesoporous carbon microspheres (NC) catalyst via spraying drying and pyrolysis processes. The highly active Fe SAs are uniformly distributed on the NC matrix, which prevented the aggregation benefiting from the enhanced Fe-N bonds. Also, the mesoporous carbon structure is favorable for fast electron and mass transfer. The optimized Fe@NC-2-900 catalyst shows positive half wave potential (E1/2 = 0.86 V vs reversible hydrogen electrodes (RHE)) and starting potential (Eonset = 0.98 V vs RHE) in ORR, which is comparable to the commercial Pt/C catalyst (E1/2= 0.87 V, Eonset = 1.08 V). Outstanding stability with a current retention rate of 92.5% for 9 hours and good methanol tolerance are achieved. The assembled zinc-air batteries showed good stability up to 500 hours at a current density of 5 mA cm-2. This work shows potentials of Fe SAs based catalysts for the practical application in ORR and pave a new avenue for promoting their catalytic performances.

3.
PLoS Pathog ; 20(7): e1012410, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39038066

RESUMO

One of the greatest challenges encountered by enteric pathogens is responding to rapid changes of nutrient availability in host. However, the mechanisms by which pathogens sense gastrointestinal signals and exploit available host nutrients for proliferation remain largely unknown. Here, we identified a two-component system in Vibrio parahaemolyticus, TtrRS, which senses environmental tetrathionate and subsequently activates the transcription of the ttrRS-ttrBCA-tsdBA gene cluster to promote V. parahaemolyticus colonization of adult mice. We demonstrated that TsdBA confers the ability of thiosulfate oxidation to produce tetrathionate which is sensed by TtrRS. TtrRS autoregulates and directly activates the transcription of the ttrBCA and tsdBA gene clusters. Activated TtrBCA promotes bacterial growth under micro-aerobic conditions by inducing the reduction of both tetrathionate and thiosulfate. TtrBCA and TsdBA activation by TtrRS is important for V. parahaemolyticus to colonize adult mice. Therefore, TtrRS and their target genes constitute a tetrathionate-responsive genetic circuit to exploit the host available sulfur compounds, which further contributes to the intestinal colonization of V. parahaemolyticus.


Assuntos
Proteínas de Bactérias , Vibrioses , Vibrio parahaemolyticus , Vibrio parahaemolyticus/metabolismo , Vibrio parahaemolyticus/genética , Animais , Camundongos , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Compostos de Enxofre/metabolismo , Regulação Bacteriana da Expressão Gênica , Feminino , Camundongos Endogâmicos C57BL
4.
J Am Chem Soc ; 146(10): 6753-6762, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38412236

RESUMO

High-temperature rechargeable batteries are essential for energy storage in elevated-temperature situations. Due to the resource abundance of potassium, high-temperature K-ion batteries are drawing increasing research interest. However, raising the working temperature would aggravate the chemical and mechanical instability of the KIB anode, resulting in very fast capacity fading, especially when high capacity is pursued. Here, we demonstrated that a porous conductive metal-organic framework (MOF), which is constructed by N-rich aromatic molecules and CuO4 units via π-d conjugation, could provide multiple accessible redox-active sites and promised robust structure stability for efficient potassium storage at high temperatures. Even working at 60 °C, this MOF anode could deliver high initial capacity (455 mAh g-1), impressive rate, and extraordinary cyclability (96.7% capacity retention for 1600 cycles), which is much better than those of reported high-temperature KIB anodes. The mechanistic study revealed that C═N groups and CuO4 units contributed abundant redox-active sites; the synergistic effect of π-d conjugated character and reticular porous architecture facilitated the K+/e- transport and ensured an insoluble electrode with small volume deformation, thus achieving stable high-capacity potassium storage.

5.
Rev Sci Instrum ; 94(6)2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37862513

RESUMO

Absolute x-ray ultraviolet diagnostics ensures 2D coverage of the radiation emission region that enables tomographic reconstruction. However, retrieving the local emissivity via tomography remains a challenge due to its ill-posed nature. Tikhonov regularization with smoothness operation generally performs well but tends to over-smooth regions with steep gradients and local structure in the radiation profile and may introduce artifacts. In this paper, a tomography method based on compressive sensing theory with Tikhonov regularization terms is developed. Experimental results on multiple phantom sets show that the proposed method improves the reconstruction accuracy and quality in regions with steep gradients compared with the Tikhonov regularization method and suppresses the unphysical negative emissivity. The analysis of reconstruction uncertainty shows that the dictionary learning process provides more accurate prior information about steep gradients to improve the quality of reconstructed images, and compressive sensing has the denoising capability to reduce the impact of noise. Finally, the method is validated by data from the Sino-UNIted Spherical Tokamak, showing fewer artifacts and more reliable reconstruction images than the earlier method.

6.
Behav Sci (Basel) ; 13(8)2023 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-37622757

RESUMO

Previous studies suggested that athletes' psychological capital level is related to life stress and burnout. Therefore, the purpose of this study was to explore the influences of university baseball athletes' psychological capital on their life stress and burnout and provide practical suggestions for athletes and coaches to reduce their life stress and burnout. In this study, we used athletes' control variables (grade, year of training experience, and training days per week) and psychological capital (self-efficacy, hope, optimism, and resilience) to predict their life stress and burnout. A total of 428 division I baseball athletes from 16 teams of the national college baseball sports league in Taiwan participated in this survey, with a return rate of 89.2%. Partial least squares structural equation modeling was used to test the relationships among the above-mentioned variables. The results showed that the athletes demographics such as grade (ß = 0.03, p > 0.05) and years of baseball training experience (ß = 0.00, p > 0.05) had no significant influences on athlete burnout, while the days of baseball training per week (ß = 0.32, p < 0.05) had a positive influence on athlete burnout. As for psychological capital, self-efficacy (ß = -0.09, p < 0.05), hope (ß = -0.27, p < 0.05), and optimism (ß = -0.20, p < 0.05) had negative influences on life stress, while resilience (ß = -0.07, p > 0.05) had no significant influences on life stress. Hope (ß = -0.20, p < 0.05) had negative influences on athlete burnout, while self-efficacy (ß = -0.00, p > 0.05), optimism (ß = -0.06, p > 0.05), and resilience (ß = -0.01, p > 0.05) had no significant influences on athlete burnout. Life stress (ß = 0.52, p < 0.05) had significant influences on the burnout. Based on our research findings, suggestions were made to reduce the athletes' life stress and athlete burnout.

7.
Microbiol Spectr ; 11(4): e0092123, 2023 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-37409954

RESUMO

Soil is an essential part of the animal habitat and has a large diversity of microbiota, while the animal body was colonized by a complex bacterial community; so far, the relationship between the animal host microbial community and the soil microbial ecosystem remains largely unknown. In this study, 15 white rhinoceros from three different captive grounds were selected and the bacterial community of the gut, skin, and environment of these rhinoceros were analyzed by 16S rRNA sequencing technology. Our results showed that Firmicutes and Bacteroidota were the predominant phyla in the gut microbiome, whereas skin and environment samples share similar microbiome profiles and are dominated by the phyla of Actinobacteriota, Chloroflexi, and Proteobacteria. Although the bacterial composition of the gut differs from that of the skin and environment, the Venn diagrams showed that there were 22 phyla and 186 genera shared by all the gut, skin, and environmental microbes in white rhinoceroses. Further cooccurrence network analysis indicated a bacterial linkage based on a complex interaction was established by the bacterial communities from the three different niches. In addition, beta diversity and bacterial composition analysis showed that both the captive ground and host ages induced shifts in the microbial composition of white rhinoceroses, which suggested that the bacterial linkage between the captive white rhinoceros and its environment is dynamic. Overall, our data contribute to a better understanding of the bacterial community of the captive white rhinoceros, especially for the relationship between the environment and animal bacterial communities. IMPORTANCE The white rhinoceros is one of the world's most endangered mammals. The microbial population plays a key role in animal health and welfare; however, studies regarding the microbial communities of the white rhinoceros are relatively limited. As the white rhinoceros has a common behavior of mud baths and thus is in direct contact with the environment, a relationship between the animal microbial community and the soil microbial ecosystem appears possible, but it remains unclear. Here, we described the characteristics and interaction of bacterial communities of the white rhinoceros in three different niches, including gut, skin, and environment. We also analyzed the effects of captive ground and age on the composition of the bacterial community. Our findings highlighted the relationship among the three niches and may have important implications for the conservation and management of this threatened species.


Assuntos
Bactérias , Microbiota , Animais , RNA Ribossômico 16S/genética , Bactérias/genética , Microbiota/genética , Perissodáctilos , Mamíferos , Sequenciamento de Nucleotídeos em Larga Escala
8.
Appl Environ Microbiol ; 89(7): e0056123, 2023 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-37404138

RESUMO

Vibrio cholerae is the causative agent of cholera. Effective intestinal colonization is a key step for V. cholerae pathogenicity and transmission. In this study, we found that deleting mshH, a homolog of the Escherichia coli CsrD protein, caused a V. cholerae colonization defect in the intestine of adult mice. By analyzing the RNA levels of CsrB, CsrC, and CsrD, we found that deleting mshH increased the levels of CsrB and CsrD but decreased the level of CsrC. However, deleting CsrB and -D not only recovered the mshH deletion mutant colonization defect but also recovered CsrC to wild-type levels. These results indicated that controlling the RNA levels of CsrB, -C, and -D is crucial for V. cholerae colonization of adult mice. We further demonstrated that the RNA levels of CsrB and CsrD were mainly controlled by MshH-dependent degradation, yet the level of CsrC was mainly determined by the CsrA-dependent stabilization. Our data show that V. cholerae differentially controls CsrB, -C, and -D abundance through the MshH-CsrB/C/D-CsrA regulatory pathway to finely regulate the activity of CsrA targets such as ToxR, so as to better survive in adult mouse intestine. IMPORTANCE The ability of V. cholerae to colonize the intestine is a key factor for its fitness and transmissibility between hosts. Here, we investigated the mechanism of V. cholerae colonization of adult mammal intestine and found that precisely controlling the CsrB, -C, and -D contents by MshH and CsrA plays an essential role for V. cholerae colonization in the adult mouse intestine. These data expand our knowledge on the mechanism of V. cholerae controlling the RNA level of CsrB, -C, and -D and highlight the importance that the different strategies used by V. cholerae to regulate the RNA level of CsrB, -C, and -D confer the bacterium with a survival advantage.


Assuntos
Cólera , Proteínas de Escherichia coli , RNA Longo não Codificante , Vibrio cholerae , Animais , Camundongos , Vibrio cholerae/genética , Vibrio cholerae/metabolismo , Proteínas Repressoras/genética , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , RNA Bacteriano/metabolismo , Escherichia coli/genética , Regulação Bacteriana da Expressão Gênica , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Mamíferos , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Proteínas de Escherichia coli/genética
9.
Microbiol Spectr ; 11(4): e0011023, 2023 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-37310220

RESUMO

Pecan (Carya illinoinensis) and Chinese hickory (Carya cathayensis) are important commercially cultivated nut trees. They are phylogenetically closely related plants; however, they exhibit significantly different phenotypes in response to abiotic stress and development. The rhizosphere selects core microorganisms from bulk soil, playing a pivotal role in the plant's resistance to abiotic stress and growth. In this study, we used metagenomic sequencing to compare the selection capabilities of seedling pecan and seedling hickory at taxonomic and functional levels in bulk soil and the rhizosphere. We observed that pecan has a stronger capacity to enrich rhizosphere plant-beneficial microbe bacteria (e.g., Rhizobium, Novosphingobium, Variovorax, Sphingobium, and Sphingomonas) and their associated functional traits than hickory. We also noted that the ABC transporters (e.g., monosaccharide transporter) and bacterial secretion systems (e.g., type IV secretion system) are the core functional traits of pecan rhizosphere bacteria. Rhizobium and Novosphingobium are the main contributors to the core functional traits. These results suggest that monosaccharides may help Rhizobium to efficiently enrich this niche. Novosphingobium may use a type IV secretion system to interact with other bacteria and thereby influence the assembly of pecan rhizosphere microbiomes. Our data provide valuable information to guide core microbial isolation and expand our knowledge of the assembly mechanisms of plant rhizosphere microbes. IMPORTANCE The rhizosphere microbiome has been identified as a fundamental factor in maintaining plant health, helping plants to fight the deleterious effects of diseases and abiotic stresses. However, to date, studies on the nut tree microbiome have been scarce. Here, we observed a significant "rhizosphere effect" on the seedling pecan. We furthermore demonstrated the core rhizosphere microbiome and function in the seedling pecan. Moreover, we deduced possible factors that help the core bacteria, such as Rhizobium, to efficiently enrich the pecan rhizosphere and the importance of the type IV system for the assembly of pecan rhizosphere bacterial communities. Our findings provide information for understanding the mechanism of the rhizosphere microbial community enrichment process.


Assuntos
Carya , Rizosfera , Carya/microbiologia , Sistemas de Secreção Tipo IV , Bactérias/genética , Fenótipo , Solo , Microbiologia do Solo
10.
Mol Microbiol ; 120(2): 241-257, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37330634

RESUMO

Vibrio parahaemolyticus is a significant food-borne pathogen that is found in diverse aquatic habitats. Quorum sensing (QS), a signaling system for cell-cell communication, plays an important role in V. parahaemolyticus persistence. We characterized the function of three V. parahaemolyticus QS signal synthases, CqsAvp , LuxMvp , and LuxSvp , and show that they are essential to activate QS and regulate swarming. We found that CqsAvp , LuxMvp , and LuxSvp activate a QS bioluminescence reporter through OpaR. However, V. parahaemolyticus exhibits swarming defects in the absence of CqsAvp , LuxMvp , and LuxSvp , but not OpaR. The swarming defect of this synthase mutant (termed Δ3AI) was recovered by overexpressing either LuxOvp D47A , a mimic of dephosphorylated LuxOvp mutant, or the scrABC operon. CqsAvp , LuxMvp , and LuxSvp inhibit lateral flagellar (laf) gene expression by inhibiting the phosphorylation of LuxOvp and the expression of scrABC. Phosphorylated LuxOvp enhances laf gene expression in a mechanism that involves modulating c-di-GMP levels. However, enhancing swarming requires phosphorylated and dephosphorylated LuxOvp which is regulated by the QS signals that are synthesized by CqsAvp , LuxMvp , and LuxSvp . The data presented here suggest an important strategy of swarming regulation by the integration of QS and c-di-GMP signaling pathways in V. parahaemolyticus.


Assuntos
Percepção de Quorum , Vibrio parahaemolyticus , Percepção de Quorum/genética , Vibrio parahaemolyticus/fisiologia , Regulação Bacteriana da Expressão Gênica , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Transdução de Sinais
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