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1.
J Am Chem Soc ; 146(2): 1619-1626, 2024 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-38166387

RESUMEN

Operation of rechargeable batteries at ultralow temperature is a significant practical problem because of poor kinetics of the electrode. Here, we report for the first time stabilized multiphase conversions for fast kinetics and long-term durability in ultralow-temperature, organic-sodium batteries. We establish that disodium rhodizonate organic electrode in conjunction with single-layer graphene oxide obviates consumption of organic radical intermediates, and demonstrate as a result that the newly designed organic electrode exhibits excellent electrochemical performance of a highly significant capacity of 130 mAh g-1 at -50 °C. We evidence that the full-cell configuration coupled with Prussian blue analogues exhibits exceptional cycling stability of >7000 cycles at -40 °C while maintaining a discharge capacity of 101 mAh g-1 at a high current density 300 mA g-1. We show this is among the best reported ultralow-temperature performance for nonaqueous batteries, and importantly, the pouch cell exhibits a continuous power supply despite conditions of -50 °C. This work sheds light on the distinct energy storage characteristics of organic electrode and opens up new avenues for the development of reliable and sustainable ultralow-temperature batteries.

2.
Environ Sci Technol ; 58(32): 14585-14593, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39072735

RESUMEN

Alcohols are promising fuels for direct alcohol fuel cells and are common scavengers to identify reactive oxygen species (ROS) in electro-Fenton (EF) systems. However, the side impacts of alcohols on oxygen reduction reactions and ROS generation are controversial due to the complex interactions between electrodes and alcohol-containing electrolytes. Herein, we employed synchrotron-Fourier-transform infrared spectroscopy and electron paramagnetic resonance technologies to directly observe the changes of chemical species and electrochemical properties on the electrode surface. Our studies suggested that alcohols exhibited different limiting degrees on proton (H+) mass transfer toward the catalytic surface, following an order of methanol < ethanol < isopropanol < tert-butyl alcohol (TBA). In addition, the formation of hydrophobic TBA clusters at high concentrations (>400 mM) resulted in a significant reduction in ionic conductivity and an elevation in charge transfer resistance, which impedes H+ mass transfer and raises the energy barrier for 2e- oxygen reduction reaction processes. Moreover, the organic radical •CH2(CH3)2CH2OH produced by the interaction of Fe3+ and •OH with the alcohol in the EF system serves as a crucial intermediate in facilitating H2O2 regeneration, which complicates the quenching effect of alcohols on •OH identification. Therefore, it is recommended that methanol should be used as the scavenger instead of TBA and the concentration should be less than 400 mM in EF systems.


Asunto(s)
Alcoholes , Peróxido de Hidrógeno , Peróxido de Hidrógeno/química , Alcoholes/química , Oxidación-Reducción , Hierro/química , Especies Reactivas de Oxígeno/química
3.
Environ Sci Technol ; 2024 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-39276341

RESUMEN

Organic contaminants with lower Hammett constants are typically more prone to being attacked by reactive oxygen species (ROS) in advanced oxidation processes (AOPs). However, the interactions of an organic contaminant with catalytic centers and participating ROS are complex and lack an in-depth understanding. In this work, we observed an abnormal phenomenon in AOPs that the degradation of electron-rich phenolics, such as 4-methoxyphenol, acetaminophen, and 4-presol, was unexpectedly slower than electron-deficient phenolics in a Mn(II)/nitrilotriacetic acid/peroxymonosulfate (Mn(II)/NTA/PMS) system. The established quantitative structure-activity relationship revealed a volcano-type dependence of the degradation rates on the Hammett constants of pollutants. Leveraging substantial analytical techniques and modeling analysis, we concluded that the electron-rich phenolics would inhibit the generation of both primary (Mn(III)NTA) and secondary (Mn(V)NTA) high-valent manganese species through complexation and competition effects. Specifically, the electron-rich phenolics would form a hydrogen bond with Mn(II)/NTA/PMS through outer-sphere interactions, thereby reducing the electrophilic reactivity of PMS to accept the electron transfer from Mn(II)NTA, and slowing down the generation of reactive Mn(III)NTA. Furthermore, the generated Mn(III)NTA is more inclined to react with electron-rich phenolics than PMS due to their higher reaction rate constants (8314 ± 440, 6372 ± 146, and 6919 ± 31 M-1 s-1 for 4-methoxyphenol, acetaminophen, and 4-presol, respectively, as compared with 671 M-1 s-1 for PMS). Consequently, the two-stage inhibition impeded the generation of Mn(V)NTA. In contrast, the complexation and competition effects are insignificant for electron-deficient phenolics, leading to declined reaction rates when the Hammett constants of pollutants increase. For practical applications, such complexation and competition effects would cause the degradation of electron-rich phenolics to be more susceptible to water matrixes, whereas the degradation of electron-deficient phenolics remains largely unaffected. Overall, this study elucidated the intricate interaction mechanisms between contaminants and reactive metal species at both the electronic and kinetic levels, further illuminating their implications for practical treatment.

4.
J Appl Microbiol ; 134(1)2023 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-36626730

RESUMEN

AIMS: To provide valuable information for a comprehensive understanding of the multicellular behavior of Bacillus velezensis Bs916 regulated by surfactin and other natural signals by Transcriptome. METHODS AND RESULTS: Transcriptomics revealed a distinct effect on gene expression alterations caused by disruption of the surfactin gene cluster(Δsrf) and 100 µg/ml surfactin addition(Δsrf + SRF). A total of 1573 differential expression genes were identified among Bs916, Δsrf, and Δsrf + SRF and grouped into eight categories based on their expression profiles. RT-qPCR analysis of 30 candidate genes showed high consistency with those of transcriptome. Additionally, the expression of eight candidate genes regulated by surfactin in a dose-dependent manner was revealed by lacZ fusion. Based on the above evidence, we proposed that surfactin can act as an extracellular signal for monitoring biofilm formation in Bs916 by directly regulating the expression of AbrB, DegS-degU, and SinI-SinR, and indirectly regulating the phosphorylation of ComA and Spo0A. CONCLUSIONS: The biofilm of Δsrf was unable to restore significantly by surfactin addition, combined inclusion of surfactin (SRF), exopolysaccharide (EPS), and γ-poly-dl-glutamic acid (γ-PGA), results in significant restoration of Δsrf biofilm formation, thereby a preliminary model was presented about the molecular mechanism by which the signaling molecule surfactin regulates Bs916 multicellular behavior.


Asunto(s)
Bacillus , Transcriptoma , Bacillus/fisiología , Perfilación de la Expresión Génica , Familia de Multigenes , Biopelículas , Bacillus subtilis/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Regulación Bacteriana de la Expresión Génica , Lipopéptidos/farmacología , Lipopéptidos/metabolismo
5.
Adv Mater ; 36(32): e2401454, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38685794

RESUMEN

Single atom catalysts (SACs) are atomic-level-engineered materials with high intrinsic activity. Catalytic centers of SACs are typically the transition metal (TM)-nonmetal coordination sites, while the functions of coexisting non-TM-bonded functionalities are usually overlooked in catalysis. Herein, the scalable preparation of carbon-supported cobalt-anchored SACs (CoCN) with controlled Co─N sites and free functional N species is reported. The role of metal- and nonmetal-bonded functionalities in the SACs for peroxymonosulfate (PMS)-driven Fenton-like reactions is first systematically studied, revealing their contribution to performance improvement and pathway steering. Experiments and computations demonstrate that the Co─N3C coordination plays a vital role in the formation of a surface-confined PMS* complex to trigger the electron transfer pathway and promote kinetics because of the optimized electronic state of Co centers, while the nonmetal-coordinated graphitic N sites act as preferable pollutant adsorption sites and additional PMS activation sites to accelerate electron transfer. Synergistically, CoCN exhibits ultrahigh activity in PMS activation for p-hydroxybenzoic acid oxidation, achieving complete degradation within 10 min with an ultrahigh turnover frequency of 0.38 min-1, surpassing most reported materials. These findings offer new insights into the versatile functions of N species in SACs and inspire rational design of high-performance catalysts in complicated heterogeneous systems.

6.
Genome ; 56(5): 273-81, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23789995

RESUMEN

Heat shock proteins (Hsps) are an evolutionarily conserved group of molecules present in all eukaryotic and prokaryotic organisms. Hsp10 and Hsp60 were originally described as the essential mitochondrial proteins involved in protein folding. Recent studies demonstrate that Hsp10 has additional roles including immune modulation. In our study, an homologous Hsp10 (Sp-Hsp10) was identified in the mud crab Scylla paramemosain, and its genomic DNA organization was determined. The cDNA sequence of Sp-Hsp10 contains an open reading frame of 309 bp, encoding a putative protein of 102 amino acid residues with approximately 10 kDa. The Sp-Hsp10 gene is located next to the Sp-Hsp60 gene and shares a 1916-bp intergenic region. The promoter activity of the Sp-Hsp10 flanking gene was analyzed using luciferase reporter assays in transfected endothelial progenitor cells. The upregulation of Sp-Hsp10 expression was detected after exposure of hemocytes to a heat shock of 1 h at 37 °C compared with unstressed hemocytes raised at 20 °C. To our knowledge, this is the first report characterizing the genomic organization of a new Hsp10 in a crustacean.


Asunto(s)
Braquiuros/genética , Chaperonina 10/genética , Regiones Promotoras Genéticas , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Chaperonina 10/metabolismo , Chaperonina 60/genética , Datos de Secuencia Molecular , Sistemas de Lectura Abierta , Filogenia , Análisis de Secuencia de ADN , Transcripción Genética
7.
Front Psychiatry ; 14: 1242367, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38025419

RESUMEN

Depression has long been considered a disease involving immune hyperactivation. The impact of pro-inflammatory cytokines such as TNF-α, IL-1ß, IL-6, and IL-8 on depression has been widely studied. However, the effect of IL-33, another pro-inflammatory cytokine, has been less researched. Currently, research on the correlation between IL-33 and depression risk is inconsistent. In response to these divergent results, we conducted a review and meta-analysis aimed at resolving published research on the correlation between IL-33 and depression risk, and understanding the potential role of IL-33 in the development and treatment of depression. After searching different databases, we analyzed 8 studies. Our meta-analysis showed that IL-33 had a positive correlation with reduced risk of depression. The pooled standard mean differences (SMD) = 0.14, 95% confidence interval (CI): 0.05-0.24. Subgroup analysis results showed that IL-33 and ST2 levels in cerebrospinal fluid and serum is positive correlated with reduced risk of major depressive disorder (MDD) and bipolar disorder (BD). According to the characteristics of the included literature, the results mainly focuses on Caucasian. Furthermore, according to the subgroup analysis of depression-related data sources for disease or treatment, the correlation between IL-33 and depression risk is reflected throughout the entire process of depression development and treatment. Therefore, the change of IL-33 level in serum and cerebrospinal fluid can serve as useful indicators for assessing the risk of depression, and the biomarker provides potential treatment strategies for reducing the burden of the disease.

8.
Front Pharmacol ; 14: 1172447, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38318311

RESUMEN

Introduction: During the coronavirus disease 2019 (COVID-19) pandemic, a large number of critically ill and severe COVID-19 patients meet the diagnostic criteria for sepsis and even septic shock. The treatments for COVID-19 patients with sepsis are still very limited. For sepsis, improving ventilation is one of the main treatments. Nitric oxide (NO) and almitrine have been reported to improve oxygenation in patients with "classical" sepsis. Here, we conducted a systematic review and meta-analysis to evaluate the efficacy and safety of NO, almitrine, and the combination of both for COVID-19 (at the edge of sepsis) patients. Method: A systematic search was performed on Embase, PubMed, the Cochrane Library, the Web of Science, Wanfang Data, and China National Knowledge Infrastructure. Randomized clinical trials, cohort studies, cross-sectional studies, case-control studies, case series, and case reports in COVID-19 patients with suspected or confirmed sepsis were performed. Study characteristics, patient demographics, interventions, and outcomes were extracted from eligible articles. Results: A total of 35 studies representing 1,701 patients met eligibility criteria. Inhaled NO did not affect the mortality (OR 0.96, 95% CI 0.33-2.8, I2 = 81%, very low certainty), hospital length of stay (SMD 0.62, 95% CI 0.04-1.17, I2 = 83%, very low certainty), and intubation needs (OR 0.82, 95% CI 0.34-1.93, I2 = 56%, very low certainty) of patients with COVID-19 (at the edge of sepsis). Meanwhile, almitrine did not affect the mortality (OR 0.44, 95% CI 0.17-1.13, low certainty), hospital length of stay (SMD 0.00, 95% CI -0.29-0.29, low certainty), intubation needs (OR 0.94, 95% CI 0.5-1.79, low certainty), and SAEs (OR 1.16, 95% CI 0.63-2.15, low certainty). Compared with pre-administration, the PaO2/FiO2 of patients with NO (SMD-0.87, 95% CI -1.08-0.66, I2 = 0%, very low certainty), almitrine (SMD-0.73, 95% CI-1.06-0.4, I2 = 1%, very low certainty), and the combination of both (SMD-0.94, 95% CI-1.71-0.16, I2 = 47%, very low certainty) increased significantly. Conclusion: Inhaled NO, almitrine, and the combination of the two drugs improved oxygenation significantly, but did not affect the patients' mortality, hospitalization duration, and intubation needs. Almitrine did not significantly increase the patients' SAEs. Well-designed high-quality studies are needed for establishing a stronger quality of evidence. Systematic Review Registration: https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=367667, identifier CRD42022367667.

9.
Research (Wash D C) ; 6: 0213, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37614364

RESUMEN

Marine organisms perform a sea of diel rhythmicity. Planktonic diel dynamics have been shown to be driven by light, energy resources, circadian rhythms, and the coordinated coupling of photoautotrophs and heterotrophic bacterioplankton. Here, we explore the diel fluctuation of viral production and decay and their impact on the total and active bacterial community in the coastal and open seawaters of the South China Sea. The results showed that the night-production diel pattern of lytic viral production was concurrent with the lower viral decay at night, contributing to the accumulation of the viral population size during the night for surface waters. The diel variations in bacterial activity, community composition, and diversity were found highly affected by viral dynamics. This was revealed by the finding that bacterial community diversity was positively correlated to lytic viral production in the euphotic zone of the open ocean but was negatively related to lysogenic viral production in the coastal ocean. Such distinct but contrasting correlations suggest that viral life strategies can not only contribute to diversifying bacterial community but also potentially piggyback their host to dominate bacterial community, suggesting the tightly synchronized depth-dependent and habitat-specific diel patterns of virus-host interactions. It further implies that viruses serve as an ecologically important driver of bacterial diel dynamics across the ocean, highlighting the viral roles in bacterial ecological and biogeochemical processes in the ocean.

10.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 6): o1759, 2012 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-22719542

RESUMEN

In the title compound, C(11)H(13)BrOS, the thio-ether unit and the phenyl ring adopt an essentially planar conformation, with a maximum deviation of 0.063 Å. In the crystal, mol-ecules are linked by C-H⋯O hydrogen bonds, extending in zigzag chains along the b axis. A weak intra-molecular C-H⋯Br hydrogen bond is also observed, which forms an S(6) ring motif.

11.
Kaohsiung J Med Sci ; 36(4): 265-273, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31889432

RESUMEN

Wilms tumor (WT) is the most common solid childhood tumors all over the world. MicroRNAs (miRs) contribute to tumorigenesis of various cancers through targeting gene. The present study investigated the vital role of miR-194-5p and its underlying mechanism in the progression of WT. Immunohistochemistry and quantitative real-time polymerase chain reaction (qRT-PCR) assay indicated downregulation of miR194-5p and upregulation of Crk, in WT tissues compared to adjacent normal tissues. Transfection with miR-194-5p mimics into nephroblastoma cells showed a significant decline in cell migration and invasion, which was detected by Transwell assay. Luciferase assay confirmed that Crk was a direct target gene of miR-194-5p. More important, the mesenchymal to epithelial transition (EMT) biomarkers containing E-cadherin, N-cadherin and Zeb1 were examined by Western blot, and revealed that miR-194-5p mimics decreased the levels of N-cadherin and Zeb1 but increased E-cadherin, which suggested that miR-194-5p inhibited EMT. Crk knockdown could reverse the increased nephroblastoma cell invasion, migration and EMT caused by miR-194-5p inhibitor. Interestingly, qRT-PCR and Western blot analysis showed that overexpression of miR-194-5p deactivated HGF/c-Met/Scr signaling pathway via targeting Crk. In conclusion, miR-194-5p inhibited nephroblastoma cell metastasis and EMT in the progression of WT by targeting Crk. Thus, miR-194-5p might be a potential target in WT particularly for the prevention of metastasis and EMT.


Asunto(s)
Transición Epitelial-Mesenquimal , MicroARNs/metabolismo , Proteínas Proto-Oncogénicas c-crk/metabolismo , Tumor de Wilms/genética , Tumor de Wilms/patología , Secuencia de Bases , Línea Celular Tumoral , Preescolar , Regulación hacia Abajo/genética , Transición Epitelial-Mesenquimal/genética , Femenino , Regulación Neoplásica de la Expresión Génica , Factor de Crecimiento de Hepatocito/metabolismo , Humanos , Lactante , Masculino , MicroARNs/genética , Metástasis de la Neoplasia , Fosforilación , Proteínas Proto-Oncogénicas c-met/metabolismo , Familia-src Quinasas/metabolismo
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