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1.
Angew Chem Int Ed Engl ; : e202404763, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38588210

RESUMO

The electrochemical CO2 reduction reaction (eCO2RR) to multicarbon products has been widely recognized for Cu-based catalysts. However, the structural changes in Cu-based catalysts during the eCO2RR pose challenges to achieving an in-depth understanding of the structure-activity relationship, thereby limiting catalyst development. Herein, we employ constant-potential density functional theory calculations to investigate the sintering process of Cu single atoms of Cu-N-C single-atom catalysts into clusters under eCO2RR conditions. Systematic constant-potential ab initio molecular dynamics simulations revealed that the leaching of Cu-(CO)x moieties and subsequent agglomeration into clusters can be facilitated by synergistic adsorption of H and eCO2RR intermediates (e.g., CO). Increasing the Cu2+ concentration or the applied potential can efficiently suppress Cu sintering. Both microkinetic simulations and experimental results further confirm that sintered Cu clusters play a crucial role in generating C2 products. These findings provide significant insights into the dynamic evolution of Cu-based catalysts and the origin of their activity toward C2 products during the eCO2RR.

2.
Respiration ; 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38588649

RESUMO

INTRODUCTION: Endobronchial ultrasound-guided transbronchial mediastinal cryobiopsy (EBUS-TMC), a novel technique, has been reported to improve the diagnostic value of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) for mediastinal lesions in recent studies. Current literature suggests that this procedure has greater diagnostic efficacy compared to conventional EBUS-TBNA. This systematic review and meta-analysis aimed to evaluate the diagnostic yield and complications associated with EBUS-TMC in comparison to EBUS-TBNA, thereby exploring the potential of this novel technique in enhancing the diagnostic utility for mediastinal lesions. METHODS: A comprehensive literature review was conducted by searching the PubMed, Embase, and Google Scholar databases for articles published from inception to December 31, 2023. The objective of this review was to evaluate the utilization of EBUS-TMC in diagnosing mediastinal disease, while also assessing the quality of each study using the QUADAS-2 tool. The diagnostic yield estimates were subjected to a meta-analysis utilizing inverse variance weighting. Furthermore, a comprehensive analysis of the complications associated with this procedure was performed. RESULTS: The meta-analysis included 10 studies involving a total of 538 patients. The findings of the meta-analysis demonstrated that EBUS-TMC yielded an overall diagnostic rate of 89.59% (482/538), while EBUS-TBNA yielded a rate of 77.13% (415/538). The calculated inverse variance-weighted odds ratio was 2.63 (95% confidence interval, 1.86-3.72; p<0.0001), and I2 value was 11%, indicating a statistically significant difference between the two techniques. The associated complications consisted of pneumothorax, pneumomediastinum, mediastinitis and bleeding, with an incidence of 0.74% (4/538), 0.37% (2/538), 0.0% (0/538), and 1.12% (6/538), respectively. Moreover, the funnel plot displayed no discernible publication bias. Further subgroup analysis revealed a notable improvement in the diagnosis value for lymphoma (86.36% vs. 27.27%, p=0.0006) and benign disorder (87.62% vs. 60.00%, p<0.0001). CONCLUSION: This review of the current available studies indicated that EBUS-TMC enhanced overall diagnostic yields compared to EBUS-TBNA, particularly for diagnosing benign disease and lymphoma. This procedure was not associated with any serious complications.

3.
BMC Pulm Med ; 24(1): 176, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38609879

RESUMO

BACKGROUND: Studies have shown that mitochondrial function and macrophages may play a role in the development of idiopathic pulmonary fibrosis (IPF). However, the understanding of the interactions and specific mechanisms between mitochondrial function and macrophages in pulmonary fibrosis is still very limited. METHODS: To construct a prognostic model for IPF based on Macrophage- related genes (MaRGs) and Mitochondria-related genes (MitoRGs), differential analysis was performed to achieve differentially expressed genes (DEGs) between IPF and Control groups in the GSE28042 dataset. Then, MitoRGs, MaRGs and DEGs were overlapped to screen out the signature genes. The univariate Cox analysis and the least absolute shrinkage and selection operator (LASSO) algorithm were implemented to achieve key genes. Furthermore, the independent prognostic analysis was employed. The ingenuity pathway analysis (IPA) was employed to further understand the molecular mechanisms of key genes.Next, the immune infiltration analysis was implemented to identify differential immune cells between two risk subgroups. RESULTS: There were 4791 DEGs between IPF and Control groups. Furthermore, 26 signature genes were achieved by the intersection processing. Three key genes including ALDH2, MCL1, and BCL2A1 were achieved, and the risk model based on the key genes was created. In addition, a nomogram for survival forecasting of IPF patients was created based on riskScore, Age, and Gender, and we found that key genes were associated with classical pathways including 'Apoptosis Signaling', 'PI3K/AKT Signaling', and so on. Next, two differential immune cells including Monocytes and CD8 T cells were identified between two risk subgroups. Moreover, we found that MIR29B2CHG and hsa-mir-1-3p could regulate the expression of ALDH2. CONCLUSION: We achieved 3 key genes including ALDH2, MCL1,, and BCL2A1 associated with IPF, providing a new theoretical basis for clinical treatment of IPF.


Assuntos
Fibrose Pulmonar Idiopática , Fosfatidilinositol 3-Quinases , Humanos , Prognóstico , Proteína de Sequência 1 de Leucemia de Células Mieloides , Macrófagos , DNA Mitocondrial , Fibrose Pulmonar Idiopática/genética , Mitocôndrias/genética , Aldeído-Desidrogenase Mitocondrial
4.
Sci Total Environ ; 927: 172268, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38583629

RESUMO

Due to the inappropriate disposal of waste materials containing lead (Pb) and irrigation with sewage containing Pb, the migration of Pb2+ within the soil profile has been extensively investigated. The conventional Pb2+ block method is challenging to implement due to its complex operational procedures and high construction costs. To address this issue, this study introduces the microbial-induced carbonate precipitation (MICP) technique as a novel approach to impede the migration of Pb2+ in the soil profile. Soil acclimatization with urea resulted in an increased proportion of urease-producing microorganisms, including Bacillus, Paenibacillus, and Planococcaceae, along with heightened expression of urea-hydrolyzing genes (UreA, UreB, UreC, and UreG). This indicates that urea-acclimatized soil (Soil-MICP) possesses the potential to induce carbonate precipitation. Batch Pb2+ fixation experiments confirmed that the fixation efficiency of Soil-MICP on Pb2+ exceeded that of soil without MICP, attributed to the MICP process within the Soil-MICP group. Dynamic migration experiments revealed that the MICP reaction transformed exchangeable lead into carbonate-bound Pb, effectively impeding Pb2+ migration in the soil profile. Additionally, the migration rate of Pb2+ in Soil-MICP was influenced by varying urea amounts, pH levels, and pore flow rates, leading to a slowdown in migration. The Two-site sorption model aptly described the Pb2+ migration process in the Soil-MICP column. This study aims to elucidate the MICP biomineralization process, uncover the in-situ blocking mechanism of MICP on lead in soil, investigate the impact of Pb on key genes involved in urease metabolism, enhance the comprehension of the chemical morphology of lead mineralization products, and provide a theoretical foundation for MICP technology in preventing the migration of Pb2+ in soil profiles.


Assuntos
Carbonatos , Chumbo , Microbiologia do Solo , Poluentes do Solo , Solo , Solo/química , Urease/metabolismo , Precipitação Química
5.
Angew Chem Int Ed Engl ; : e202404574, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38638104

RESUMO

The electrocatalytic CO2 reduction reaction (CO2RR) is a sustainable route for converting CO2 into value-added fuels and feedstocks, advancing a carbon-neutral economy. The electrolyte critically influences CO2 utilization, reaction rate and product selectivity. While typically conducted in neutral/alkaline aqueous electrolytes, the CO2RR faces challenges due to (bi)carbonate formation and its crossover to the anolyte, reducing efficiency and stability. Acidic media offer promise by suppressing these processes, but the low Faradaic efficiency, especially for multicarbon (C2+) products, and poor electrocatalyst stability persist. The effective regulation of the reaction environment at the cathode is essential to favor the CO2RR over the competitive hydrogen evolution reaction (HER) and improve long-term stability. This review examines progress in the acidic CO2RR, focusing on reaction environment regulation strategies such as electrocatalyst design, electrode modification and electrolyte engineering to promote the CO2RR. Insights into the reaction mechanisms via in situ/operando techniques and theoretical calculations are discussed, along with critical challenges and future directions in acidic CO2RR technology, offering guidance for developing practical systems for the carbon-neutral community.

7.
Hortic Res ; 11(4): uhae041, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38638682

RESUMO

Long non-coding RNAs (lncRNAs) play essential roles in various biological processes, such as chromatin remodeling, post-transcriptional regulation, and epigenetic modifications. Despite their critical functions in regulating plant growth, root development, and seed dormancy, the identification of plant lncRNAs remains a challenge due to the scarcity of specific and extensively tested identification methods. Most mainstream machine learning-based methods used for plant lncRNA identification were initially developed using human or other animal datasets, and their accuracy and effectiveness in predicting plant lncRNAs have not been fully evaluated or exploited. To overcome this limitation, we retrained several models, including CPAT, PLEK, and LncFinder, using plant datasets and compared their performance with mainstream lncRNA prediction tools such as CPC2, CNCI, RNAplonc, and LncADeep. Retraining these models significantly improved their performance, and two of the retrained models, LncFinder-plant and CPAT-plant, alongside their ensemble, emerged as the most suitable tools for plant lncRNA identification. This underscores the importance of model retraining in tackling the challenges associated with plant lncRNA identification. Finally, we developed a pipeline (Plant-LncPipe) that incorporates an ensemble of the two best-performing models and covers the entire data analysis process, including reads mapping, transcript assembly, lncRNA identification, classification, and origin, for the efficient identification of lncRNAs in plants. The pipeline, Plant-LncPipe, is available at: https://github.com/xuechantian/Plant-LncRNA-pipline.

8.
New Phytol ; 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38515251

RESUMO

MicroRNAs are essential in plant development and stress resistance, but their specific roles in drought stress require further investigation. Here, we have uncovered that a Populus-specific microRNAs (miRNA), miR6445, targeting NAC (NAM, ATAF, and CUC) family genes, is involved in regulating drought tolerance of poplar. The expression level of miR6445 was significantly upregulated under drought stress; concomitantly, seven targeted NAC genes showed significant downregulation. Silencing the expression of miR6445 by short tandem target mimic technology significantly decreased the drought tolerance in poplar. Furthermore, 5' RACE experiments confirmed that miR6445 directly targeted NAC029. The overexpression lines of PtrNAC029 (OE-NAC029) showed increased sensitivity to drought compared with knockout lines (Crispr-NAC029), consistent with the drought-sensitive phenotype observed in miR6445-silenced strains. PtrNAC029 was further verified to directly bind to the promoters of glutathione S-transferase U23 (GSTU23) and inhibit its expression. Both Crispr-NAC029 and PtrGSTU23 overexpressing plants showed higher levels of PtrGSTU23 transcript and GST activity while accumulating less reactive oxygen species (ROS). Moreover, poplars overexpressing GSTU23 demonstrated enhanced drought tolerance. Taken together, our research reveals the crucial role of the miR6445-NAC029-GSTU23 module in enhancing poplar drought tolerance by regulating ROS homeostasis. This finding provides new molecular targets for improving the drought resistance of trees.

9.
Nucleic Acids Res ; 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38554114

RESUMO

Transcriptional pausing aids gene regulation by cellular RNA polymerases (RNAPs). A surface-exposed domain inserted into the catalytic trigger loop (TL) of Escherichia coli RNAP, called SI3, modulates pausing and is essential for growth. Here we describe a viable E. coli strain lacking SI3 enabled by a suppressor TL substitution (ß'Ala941→Thr; ΔSI3*). ΔSI3* increased transcription rate in vitro relative to ΔSI3, possibly explaining its viability, but retained both positive and negative effects of ΔSI3 on pausing. ΔSI3* inhibited pauses stabilized by nascent RNA structures (pause hairpins; PHs) but enhanced other pauses. Using NET-seq, we found that ΔSI3*-enhanced pauses resemble the consensus elemental pause sequence whereas sequences at ΔSI3*-suppressed pauses, which exhibited greater association with PHs, were more divergent. ΔSI3*-suppressed pauses also were associated with apparent pausing one nucleotide upstream from the consensus sequence, often generating tandem pause sites. These '-2 pauses' were stimulated by pyrophosphate in vitro and by addition of apyrase to degrade residual NTPs during NET-seq sample processing. We propose that some pauses are readily reversible by pyrophosphorolysis or single-nucleotide cleavage. Our results document multiple ways that SI3 modulates pausing in vivo and may explain discrepancies in consensus pause sequences in some NET-seq studies.

10.
Biol Trace Elem Res ; 2024 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-38492120

RESUMO

Exposure to metal mixtures compromises the immune system, with the complement system connecting innate and adaptive immunity. Herein, we sought to explore the relationships between blood cell metal mixtures and the third and fourth components of serum complement (C3, C4). A total of 538 participants were recruited in November 2017, and 289 participants were followed up in November 2021. We conducted a cross-sectional analysis at baseline and a longitudinal analysis over 4 years. Least Absolute Shrinkage and Selection Operator (LASSO) was employed to identify the primary metals related to serum C3, C4; generalized linear model (GLM) was further used to evaluate the cross-sectional associations of the selected metals and serum C3, C4. Furthermore, participants were categorized into three groups according to the percentage change in metal concentrations over 4 years. GLM was performed to assess the associations between changes in metal concentrations and changes in serum C3, C4 levels. At baseline, each 1-unit increase in log10-transformed in magnesium, manganese, copper, rubidium, and lead was significantly associated with a change in serum C3 of 0.226 (95% CI: 0.146, 0.307), 0.055 (95% CI: 0.022, 0.088), 0.113 (95% CI: 0.019, 0.206), - 0.173 (95% CI: - 0.262, - 0.083), and - 0.020 (95% CI: - 0.039, - 0.001), respectively. Longitudinally, decreased copper concentrations were negatively associated with an increment in serum C3 levels, while decreased lead concentrations were positively associated with an increment in serum C3 levels. However, no metal was found to be primarily associated with serum C4 in LASSO, so we did not further explore the relationship between them. Our research indicates that copper and lead may affect complement system homeostasis by influencing serum C3 levels. Further investigation is necessary to elucidate the underlying mechanisms.

11.
Nano Lett ; 24(13): 3961-3970, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38526195

RESUMO

Developing a high-performance membrane electrode assembly (MEA) poses a formidable challenge for fuel cells, which lies in achieving both high metal loading and efficient catalytic activity concurrently for MEA catalysts. Here, we introduce a porous Co@NC carrier to synthesize sub-4 nm PtCo intermetallic nanocrystals, achieving an impressive Pt loading of 27 wt %. The PtCo-CoNC catalyst demonstrates exceptional catalytic activity and remarkable stability for the oxygen reduction reaction. Advanced characterization techniques and theoretical calculations emphasize the synergistic effect between PtCo alloys and single Co atoms, which enhances the desorption of the OH* intermediate. Furthermore, the PtCo-CoNC-based cathode delivers a high power density of 1.22 W cm-2 in the MEA test owing to the enhanced mass transport, which is verified by the simulation results of the O2 distributions and current density inside the catalyst layer. This study lays the groundwork for the design of efficient catalysts with practical applications in fuel cells.

12.
Pharmacol Rep ; 76(2): 263-272, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38472637

RESUMO

Renal tubulointerstitial fibrosis (RTIF) is a common feature and inevitable consequence of all progressive chronic kidney diseases, leading to end-stage renal failure regardless of the initial cause. Although research over the past few decades has greatly improved our understanding of the pathophysiology of RTIF, until now there has been no specific treatment available that can halt the progression of RTIF. Norcantharidin (NCTD) is a demethylated analogue of cantharidin, a natural compound isolated from 1500 species of medicinal insect, the blister beetle (Mylabris phalerata Pallas), traditionally used for medicinal purposes. Many studies have found that NCTD can attenuate RTIF and has the potential to be an anti-RTIF drug. This article reviews the recent progress of NCTD in the treatment of RTIF, with emphasis on the pharmacological mechanism of NCTD against RTIF.


Assuntos
Nefropatias , Humanos , Nefropatias/tratamento farmacológico , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Compostos Bicíclicos Heterocíclicos com Pontes/uso terapêutico , Fibrose
13.
Child Abuse Negl ; 151: 106736, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38522146

RESUMO

BACKGROUND: Although people strive for meaning in life, life is full of experiences that challenge meaning. According to Bowen's family systems theory, the family is both a relational and an emotional system in which family members influence and are influenced by each other. Invalidating environment, reflecting a deficient family emotional setting, may be a key influencing factor in diminishing meaning in life. Existing studies have not directly explored the effects of the invalidating environment on meaning in life and its underlying mechanism. OBJECTIVE: Guided by Bowen's family systems theory, this study aims to explore the relationship between invalidating environment and meaning in life, as well as the mediating effects of regulatory emotional self-efficacy and the satisfaction of basic psychological needs. METHODS: A sample of 555 university students (62.5 % female, 37.5 % male; Mage =19.13 years old, SD = 1.72) completed questionnaires regarding demographics, invalidating environment, meaning in life, regulatory emotional self-efficacy, and basic psychological needs satisfaction. RESULTS: Results revealed that: (a) invalidating environment negatively predicts meaning in life; (b) regulatory emotional self-efficacy and basic psychological needs satisfaction serve as both independent and chain mediators between invalidating environment and meaning in life. CONCLUSION: Invalidating environment affects meaning in life through regulatory emotional self-efficacy and basic psychological needs satisfaction. This finding has significant theoretical implications and provides a feasible pathway to improve children's meaning in life at both the parent and child levels.


Assuntos
Família , Autoeficácia , Criança , Humanos , Masculino , Feminino , Adulto Jovem , Adulto , Emoções , Satisfação Pessoal , Pais
14.
J Org Chem ; 89(7): 4877-4887, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38457276

RESUMO

General and convenient visible-light-promoted alkylsulfonylation and cyanoalkylsulfonylation of MBH adducts have been developed through the multicomponent insertion of sulfur dioxide, enabling the assembly of two C-S bonds to generate structurally diverse allylic alkylsulfones (43 examples in total). The reaction of MBH adducts with potassium alkyltrifluoroborates and 1,4-diazabicyclo[2.2.2]octane bis(sulfur dioxide) adduct afforded sulfones with generally good yields. Notably, the addition of N,N,N',N'-tetramethylethylenediamine as a base into the photocatalytic system led to yielding an alkyl sulfonyl unit and cyano group-anchored trisubstituted alkenes by utilizing cycloketone oxime esters as C-radical precursors. Both of these reactions have constructed two C-S bonds, and all desired products were obtained in moderate to excellent yields with complete stereospecificity.

18.
Angew Chem Int Ed Engl ; 63(16): e202319936, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38372428

RESUMO

Revealing the dynamic reconstruction process and tailoring advanced copper (Cu) catalysts is of paramount significance for promoting the conversion of CO2 into ethylene (C2H4), paving the way for carbon neutralization and facilitating renewable energy storage. In this study, we initially employed density functional theory (DFT) and molecular dynamics (MD) simulations to elucidate the restructuring behavior of a catalyst under electrochemical conditions and delineated its restructuring patterns. Leveraging insights into this restructuring behavior, we devised an efficient, low-coordination copper-based catalyst. The resulting synthesized catalyst demonstrated an impressive Faradaic efficiency (FE) exceeding 70 % for ethylene generation at a current density of 800 mA cm-2. Furthermore, it showed robust stability, maintaining consistent performance for 230 hours at a cell voltage of 3.5 V in a full-cell system. Our research not only deepens the understanding of the active sites involved in designing efficient carbon dioxide reduction reaction (CO2RR) catalysts but also advances CO2 electrolysis technologies for industrial application.

19.
Artigo em Inglês | MEDLINE | ID: mdl-38409719

RESUMO

BACKGROUND: As a malignant tumor, osteosarcoma (OS) ranks first place among adolescent cancers and is susceptible to developing resistance to chemotherapeutic agents. Differently, traditional Chinese medicine (TCM) has multiple pharmacodynamic targets and complex biological components, which can inhibit tumor survival and drug resistance and gradually play an important role in the treatment of sarcoma. METHODS: This study is to systematically evaluate the safety and efficacy of TCM combined with chemotherapy performed in the clinical treatment of OS. Based on multiple mainstream databases, eleven articles on the relationship between natural products and chemotherapy involving 656 patients were selected from all the literature published as of June 2022. Revman 5.4 software was used for a comprehensive search analysis, supplemented by established exclusion criteria, the Jadad scale, and the evaluation methods provided by Cochrane. RESULTS: The efficiency of TCM combined with chemotherapy was significantly increased compared with chemical drugs alone [OR=2.56, 95% CI (1.36,4.79), Z=2.92, P=0.003]. Meanwhile, the adverse reactions such as nausea and vomiting, hepatotoxicity, and hematological changes caused by chemical drugs were alleviated correspondingly. CONCLUSION: This study indicates that the mode of TCM combined with chemotherapy sheds light on the clinical treatment of OS, which is much better than the one-way mode.

20.
Molecules ; 29(4)2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38398533

RESUMO

We present the first example of visible-light-mediated multicomponent annulation of 1,7-diynes by taking advantage of quadruple cleavage olf carbon-halogen bonds of BrCCl3 to generate a C1 synthon, which was adeptly applied to the preparation of skeletally diverse 3-benzoyl-quinolin-2(1H)-one acetates in moderate to good yields. Controlled experiments demonstrated that H2O acted as both oxygen and hydrogen sources, and gem-dichlorovinyl carbonyl compound exhibited as a critical intermediate in this process. The mechanistic pathway involves Kharasch-type addition/6-exo-dig cyclization/1,5-(SN")-substitution/elimination/binucleophilic 1,6-addition/proton transfer/tautomerization sequence.

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