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1.
Proc Natl Acad Sci U S A ; 119(13): e2201665119, 2022 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-35316136

RESUMO

SignificanceAdjusting the floating states when objects float on water shows great potential for assembly, mineral flotation, nanostructured construction, and floating robot design, but the real-time regulation of floating states is challenging. Inspired by the different floating states of a falling fruit, we propose a facile strategy to transform the object between different floating states based on a three-segment three-phase contact line evolution. In addition, the potential of floating state transformation in solar-powered water evaporation, interface catalysis, and drug delivery is demonstrated. These findings provide insights into floating regulation and show great potential for floating-related applications.


Assuntos
Sistemas de Liberação de Medicamentos , Nanoestruturas , Água
2.
BMC Genomics ; 25(1): 2, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38166565

RESUMO

BACKGROUND: The infection of carbapenem-resistant organisms was a huge threat to human health due to their global spread. Dealing with a carbapenem-resistant Serratia marcescens (CRSM) infection poses a significant challenge in clinical settings. This study aims to provide insights into strategies for controlling CRSM infection by exploring the transformation mechanism of carbapenem-resistance. METHODS: We used whole genome sequencing (WGS) to investigate the mechanism of carbapenem resistance in 14 S. marcescens isolates in vivo. The expression level of related genes and the minimum inhibitory concentration of meropenem (MICMEM) were also evaluated to confirm the mechanism of carbapenem resistance. RESULTS: Seven groups of S. marcescens, each consisting of two strains, were collected from a hospital and displayed a shift in MICMEM from low to high levels. Homology analysis revealed that the isolates in five groups were significantly different from the remaining two. WGS and experimental evidence indicated that four groups of strains developed carbapenem resistance by acquiring the blaKPC (obtaining group), while two groups (persisting group) increased the expression level of the blaKPC. In contrast, isolates in the last group (missing group) did not carry the blaKPC. All strains possessed multiple ß-lactamase genes, including blaCTX-M-14, blaSRT-1, and blaSRT-2. However, only in the missing group, the carbapenem-resistant strain lost an outer membrane protein-encoding gene, leading to increased blaCTX-M-14 expression compared to the carbapenem-susceptible strain. CONCLUSION: The study findings suggest that S. marcescens strains developed diverse carbapenem resistance in vivo through the evolution of drug resistance, rather than through clone replacement. We hypothesize that carbapenem resistance in S. marcescens was due to certain clonal types with a distinct mechanism.


Assuntos
Carbapenêmicos , Serratia marcescens , Humanos , Carbapenêmicos/farmacologia , Meropeném/farmacologia , beta-Lactamases/genética , beta-Lactamases/metabolismo , Testes de Sensibilidade Microbiana , Antibacterianos/farmacologia
3.
Environ Sci Technol ; 58(26): 11695-11706, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38877970

RESUMO

Aminophenyl sulfone compounds (ASCs) are widely used in various fields, such as the pharmaceutical and textile industries. ASCs and their primary acetylation products are inevitably discharged into the environment. However, the high toxicity of ASCs could be released from the deacetylation of acetylation products. Still, the occurrence and ecological risks of ASCs and their acetylation products remain largely unknown. Here, we integrated all of the existing ASCs based on the core structure, together with their potential acetylation products, to establish a database covering 1105 compounds. By combining the database with R programming, 45 ASCs, sulfonamides, and their acetylation products were identified in the influent and effluent of 19 municipal wastewater treatment plants in 4 cities of China. 13 of them were detected for the first time in the aquatic environment, and 12 acetylation products were newly identified. The cumulative concentrations of 45 compounds in the influent and effluent were in the range of 231-9.96 × 103 and 26-2.70 × 103 ng/L, respectively. The proportion of the unrecognized compounds accounted for 60.6% of the influent and 62.8% of the effluent. Furthermore, nearly half of the ASCs (46.7%), other sulfonamides (49.9%), and their acetylation products (46.2%) were discharged from the effluent, posing a low-to-medium risk to aquatic organisms. The results provide a guideline for future monitoring programs, particularly for sulfadiazine and dronedarone, and emphasize that the ecological risk of ASCs, sulfonamides, and their acetylation products needs to be considered in the aquatic environment.


Assuntos
Sulfonamidas , Águas Residuárias , Poluentes Químicos da Água , Águas Residuárias/química , Sulfonamidas/análise , Acetilação , Antibacterianos , Eliminação de Resíduos Líquidos , China , Sulfonas , Monitoramento Ambiental
4.
J Nat Prod ; 87(7): 1778-1785, 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-38949068

RESUMO

Ten undocumented carbazole derivatives (2-11) along with the reported analogue (1) were isolated from the mangrove-derived Streptomyces sp. OUCMDZ-5511, cultured with NaBr-supplemented liquid medium. Compounds 1-7 are brominated carbazoles, and 8, 10, and 11 feature an additional thiazole or 2,3-dihydro-1,4-oxathiine rings, respectively. Their structures were identified through spectroscopic techniques, computational chemistry, and X-ray crystallography. Notably, compounds 6 and 8 effectively inhibited immune cell migration, indicating anti-inflammatory activity in vivo, potentially via Myd88/Nf-κB pathways, as suggested for compound 6.


Assuntos
Carbazóis , Streptomyces , Streptomyces/química , Carbazóis/química , Carbazóis/farmacologia , Carbazóis/isolamento & purificação , Estrutura Molecular , Cristalografia por Raios X , Bromo/química , Enxofre/química , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Biologia Marinha , NF-kappa B/antagonistas & inibidores , NF-kappa B/metabolismo , Animais
5.
Environ Res ; 247: 118276, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38246299

RESUMO

Ambient PM2.5 exposure has been recognized as a major health risk and related to aging, cardiovascular, respiratory and neurologic diseases, and cancer. However, underlying mechanism of epigenetic alteration and regulated pathways still remained unclear. The study on methylome effect of PM2.5 exposure was quite limited in Chinese population, and cohort-based study was absent. The study included blood-derived DNA methylation for 3365 Chinese participants from the NSPT cohort. We estimated individual PM2.5 exposure level of short-medium-, medium- and long-term, based on a validated prediction model. We preformed epigenome-wide association studies to estimate the links between PM2.5 exposure and DNA methylation change, as well as stratification and sensitive analysis to examined the robustness of the association models. A systematic review was conducted to obtain the previously published CpGs and examined for replication. We also conducted comparison on the DNA methylation variation corresponding to different time windows. We further conducted gene function analysis and pathway enrichment analysis to reveal related biological response. We identified a total of 177 CpGs and 107 DMRs associated with short-medium-term PM2.5 exposure, at a strict genome-wide significance (P < 5 × 10-8). The effect sizes on most CpGs tended to cease with the exposure of extended time scale. Associated markers and aligned genes were related to aging, immunity, inflammation and carcinogenesis. Enriched pathways were mostly involved in cell cycle and cell division, signal transduction, inflammatory pathway. Our study is the first EWAS on PM2.5 exposure conducted in large-scale Han Chinese cohort and identified associated DNA methylation change on CpGs and regions, as well as related gene functions and pathways.

6.
Nano Lett ; 23(20): 9367-9374, 2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37807279

RESUMO

CuOx/C catalysts have been used in the selective catalytic reduction of NOx because of the exceptional low-temperature denitration (de-NOx) activity. A fundamental understanding of the reaction between CuO and C is critical for controlling the component of CuOx/C and thus optimizing the catalytic performance. In this study, a transmission electron microscope equipped with an in situ heating device was utilized to investigate the atomic-scale reaction between CuO and C. We report two reaction mechanisms relying on the volume ratio between C and CuO: (1) The reduction from CuO to Cu2O (when the ratio is < ∼31%); (2) the reduction of CuO into polycrystalline Cu (when the ratio is > ∼34%). The atomistic reduction pathway can be well interpreted by considering the diffusion of O vacancy through the first-principle calculations. The atomic-scale exploration of CuO/C offers ample prospects for the design of industrial de-NOx catalysts in the future.

7.
Int J Mol Sci ; 25(14)2024 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-39062956

RESUMO

Exosomes are small vesicles containing proteins, nucleic acids, and biological lipids, which are responsible for intercellular communication. Studies have shown that exosomes can be utilized as effective drug delivery vehicles to accurately deliver therapeutic substances to target tissues, enhancing therapeutic effects and reducing side effects. Mesenchymal stem cells (MSCs) are a class of stem cells widely used for tissue engineering, regenerative medicine, and immunotherapy. Exosomes derived from MSCs have special immunomodulatory functions, low immunogenicity, the ability to penetrate tumor tissues, and high yield, which are expected to be engineered into efficient drug delivery systems. Despite the promising promise of MSC-derived exosomes, exploring their optimal preparation methods, drug-loading modalities, and therapeutic potential remains challenging. Therefore, this article reviews the related characteristics, preparation methods, application, and potential risks of MSC-derived exosomes as drug delivery systems in order to find potential therapeutic breakthroughs.


Assuntos
Sistemas de Liberação de Medicamentos , Exossomos , Células-Tronco Mesenquimais , Exossomos/metabolismo , Humanos , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/citologia , Sistemas de Liberação de Medicamentos/métodos , Animais , Portadores de Fármacos/química , Neoplasias/terapia
8.
J Am Chem Soc ; 145(22): 11959-11968, 2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-37216562

RESUMO

In the pursuit of a highly reversible lithium-oxygen (Li-O2) battery, control of reaction sites to maintain stable conversion between O2 and Li2O2 at the cathode side is imperatively desirable. However, the mechanism involving the reaction site during charging remains elusive, which, in turn, imposes challenges in recognition of the origin of overpotential. Herein, via combined investigations by in situ atomic force microscopy (AFM) and electrochemical impedance spectroscopy (EIS), we propose a universal morphology-dictated mechanism of efficient reaction sites for Li2O2 decomposition. It is found that Li2O2 deposits with different morphologies share similar localized conductivities, much higher than that reported for bulk Li2O2, enabling the reaction site not only at the electrode/Li2O2/electrolyte interface but also at the Li2O2/electrolyte interface. However, while the mass transport process is more enhanced at the former, the charge-transfer resistance at the latter is sensitively related to the surface structure and thus the reactivity of the Li2O2 deposit. Consequently, for compact disk-like deposits, the electrode/Li2O2/electrolyte interface serves as the dominant decomposition site, which causes premature departure of Li2O2 and loss of reversibility; on the contrary, for porous flower-like and film-like Li2O2 deposits bearing a larger surface area and richer surface-active structures, both the interfaces are efficient for decomposition without premature departure of the deposit so that the overpotential arises primarily from the sluggish oxidation kinetics and the decomposition is more reversible. The present work provides instructive insights into the understanding of the mechanism of reaction sites during the charge process, which offers guidance for the design of reversible Li-O2 batteries.

9.
Anal Chem ; 95(15): 6458-6466, 2023 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-37027511

RESUMO

The (5 × 5) Moiré pattern resulting from coadsorption of Cu atoms and chloride ions on the Au(111) electrode is one of the most classical structures for underpotential deposition (UPD) in electrochemical surface science. Although two models have been proposed to describe the pattern, the details of the structure remain ambiguous and controversial, leading to a question that remains to be answered. In this work, we investigate the UPD behaviors of Cu on the Au(111) electrode in a chloride-based deep eutectic solvent ethaline by in situ scanning tunneling microscopy (STM). Benefiting from the properties of the ultraconcentrated electrolyte, we directly image not only Cu but also Cl adlayers by finely tuning tunneling conditions. The structure is unambiguously determined for both Cu and Cl adlayers, where an incommensurate Cu layer is adsorbed on the Au(111) surface with a Cu coverage of 0.64, while the Cl coverage is 0.32 (only half of the expected value); i.e., the atomic arrangement of the observed (5 × 5) Moiré pattern in ethaline matches neither of the models proposed in the literature. Meanwhile, STM results confirm the origin of the cathodic peak in the cyclic voltammogram, which indicates that the underpotential shift of Cu UPD in ethaline indeed increases by ca. 0.40 V compared to its counterpart in a sulfuric acid solution, resulting in a significant deviation from the linear relation between the underpotential shift and the difference in work functions proposed in the literature. The unconventional electrochemical behaviors of Cu UPD reveal the specialty of both the bulk and the interface in the chloride-based deep eutectic solvent.

10.
Small ; 19(21): e2206380, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36828786

RESUMO

Deformation twinning merits attention because of its intrinsic importance as a mode of energy dissipation in solids. Herein, through the atomistic electron microscopy observations, the size-dependent twinning mechanisms in refractory body-centered cubic molybdenum nanocrystals (NCs) under tensile loading are shown. Two distinct twinning mechanisms involving the nucleation of coherent and inclined twin boundaries (TBs) are uncovered in NCs with smaller (diameter < ≈5 nm) and larger (diameter > ≈5 nm) diameters, respectively. Interestingly, the ultrahigh pseudo-elastic strain of ≈41% in sub-5 nm-sized crystals is achieved through the reversible twinning mechanism. A typical TB cross-transition mechanism is found to accommodate the NC re-orientation during the pseudo-elastic deformation. More importantly, the effects of different types of TBs on the electrical conductivity based on the repeatable experimental measurements and first-principles calculations are quantified. These size-dependent mechanical and electrical properties may prove essential in advancing the design of next-generation flexible nanoelectronics.

11.
J Nanobiotechnology ; 21(1): 489, 2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-38111035

RESUMO

Orthotopic advanced hepatic tumor resection without precise location and preoperative downstaging may cause clinical postoperative recurrence and metastasis. Early accurate monitoring and tumor size reduction based on the multifunctional diagnostic-therapeutic integration platform could improve real-time imaging-guided resection efficacy. Here, a Near-Infrared II/Photoacoustic Imaging/Magnetic Resonance Imaging (NIR-II/PAI/MRI) organic nanoplatform IRFEP-FA-DOTA-Gd (IFDG) is developed for integrated diagnosis and treatment of orthotopic hepatic tumor. The IFDG is designed rationally based on the core "S-D-A-D-S" NIR-II probe IRFEP modified with folic acid (FA) for active tumor targeting and Gd-DOTA agent for MR imaging. The IFDG exhibits several advantages, including efficient tumor tissue accumulation, good tumor margin imaging effect, and excellent photothermal conversion effect. Therefore, the IFDG could realize accurate long-term monitoring and photothermal therapy non-invasively of the hepatic tumor to reduce its size. Next, the complete resection of the hepatic tumor in situ lesions could be realized by the intraoperative real-time NIR-II imaging guidance. Notably, the preoperative downstaging strategy is confirmed to lower the postoperative recurrence rate of the liver cancer patients under middle and advanced stage effectively with fewer side effects. Overall, the designed nanoplatform demonstrates great potential as a diagnostic-therapeutic integration platform for precise imaging-guided surgical navigation of orthotopic hepatic tumors with a low recurrence rate after surgery, providing a paradigm for diagnosing and treating the advanced tumors in the future clinical translation application.


Assuntos
Neoplasias Hepáticas , Nanopartículas , Cirurgia Assistida por Computador , Humanos , Fototerapia , Imageamento por Ressonância Magnética/métodos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/cirurgia , Linhagem Celular Tumoral
12.
Neurosurg Rev ; 46(1): 118, 2023 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-37166553

RESUMO

The novel robot-assisted (RA) technique has been utilized increasingly to improve the accuracy of cervical pedicle screw placement. Although the clinical application of the RA technique has been investigated in several case series and comparative studies, the superiority and safety of RA over conventional freehand (FH) methods remain controversial. Meanwhile, the intra-pedicular accuracy of the two methods has not been compared for patients with cervical traumatic conditions. This study aimed to compare the rate and risk factors of intra-pedicular accuracy of RA versus the conventional FH approach for posterior pedicle screw placement in cervical traumatic diseases. A total of 52 patients with cervical traumatic diseases who received cervical screw placement using RA (26 patients) and FH (26 patients) techniques were retrospectively included. The primary outcome was the intra-pedicular accuracy of cervical pedicle screw placement according to the Gertzbin-Robbins scale. Secondary outcome parameters included surgical time, intraoperative blood loss, postoperative drainage, postoperative hospital stay, and complications. Moreover, the risk factors that possibly affected intra-pedicular accuracy were assessed using univariate analyses. Out of 52 screws inserted using the RA method, 43 screws (82.7%) were classified as grade A, with the remaining 7 (13.5%) and 2 (3.8%) screws classified as grades B and C. In the FH cohort, 60.8% of the 79 screws were graded A, with the remaining screws graded B (21, 26.6%), C (8, 10.1%), and D (2, 2.5%). The RA technique showed a significantly higher rate of optimal intra-pedicular accuracy than the FH method (P = 0.008), but there was no significant difference between the two groups in terms of clinically acceptable accuracy (P = 0.161). Besides, the RA technique showed remarkably longer surgery time, less postoperative drainage, shorter postoperative hospital stay, and equivalent intraoperative blood loss and complications than the FH technique. Furthermore, the univariate analyses showed that severe obliquity of the lateral atlantoaxial joint in the coronal plane (P = 0.003) and shorter width of the lateral mass at the inferior margin of the posterior arch (P = 0.014) were risk factors related to the inaccuracy of C1 screw placement. The diagnosis of HRVA (P < 0.001), severe obliquity of the lateral atlantoaxial joint in the coronal plane (P < 0.001), short pedicle width (P < 0.001), and short pedicle height (P < 0.001) were risk factors related to the inaccuracy of C2 screw placement. RA cervical pedicle screw placement was associated with a higher rate of optimal intra-pedicular accuracy to the FH technique for patients with cervical traumatic conditions. The severe obliquity of the lateral atlantoaxial joint in the coronal plane independently contributed to high rates of the inaccuracy of C1 and C2 screw placements. RA pedicle screw placement is safe and useful for cervical traumatic surgery.


Assuntos
Articulação Atlantoaxial , Parafusos Pediculares , Robótica , Fusão Vertebral , Humanos , Parafusos Pediculares/efeitos adversos , Estudos Retrospectivos , Vértebras Cervicais/cirurgia , Fusão Vertebral/métodos
13.
Pestic Biochem Physiol ; 196: 105606, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37945228

RESUMO

Metalaxyl (MTL), a germicidal agent, is widely used in agriculture. Due to the biological amplification effect, MTL entering the ecological environment would result in a threat to human health through the food chain. MTL is reportedly accumulated in liver. The objectives of the study included investigating the metabolic activation of MTL in liver and defining the mechanisms participating in the hepatotoxicity of MTL. The corresponding glutathione (GSH), N-acetylcysteine (NAC) conjugate, and cysteine conjugates were observed in liver microsomes, prepared from liver tissues of mice, containing MTL and GSH, NAC or cysteine. These conjugates were also detected in urine and bile of rats receiving MTL. Apparently, MTL was biotransformed to a quinone imine intermediate dose-dependently attacking the thiols and cysteine residues of protein. The bioactivation of MTL required cytochrome P450 enzymes, and CYP3A dominated the bio-activation of MTL.


Assuntos
Praguicidas , Ratos , Humanos , Camundongos , Animais , Ativação Metabólica , Praguicidas/toxicidade , Praguicidas/metabolismo , Cisteína/metabolismo , Cisteína/farmacologia , Microssomos Hepáticos/metabolismo , Glutationa/metabolismo
14.
Anal Chem ; 94(27): 9775-9784, 2022 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-35759408

RESUMO

Near-infrared (NIR) photothermal transduction agents (PTAs) with large rigid π-extended and planar structures are prone to aggregate in a physiological environment where their emission is often quenched due to the strong intermolecular dipole-dipole or π-π interactions. This aggregation-caused quenching effect greatly impedes their applications in image-guided photothermal theranostics. Herein, we made an interesting finding that engineering a bioinspired protein corona (PC), once thermodynamically stabilized in preferred orientations on PTA nanoaggregates, can produce brilliant NIR fluorescence with a high quantum yield (∼6.2%) without compromising their photothermal properties. Both experimental data and computational modeling suggest that the mechanism of fluorescence enhancement is due to the high-affinity binding of nano-sized PTA to albumin, which regulates the molecular conformation and aggregation state of PTA. High spatial and temporal resolution imaging of albumin PC-coated PTA aggregates enables image-guided photothermal therapy for cancer cells in sentinel lymph nodes to remarkably inhibit pulmonary metastasis. Such a treatment combined with the surgical removal of the primary tumor can prolong animal survival, which is a promising candidate for clinical applications in the treatment of advanced metastatic cancers.


Assuntos
Neoplasias , Coroa de Proteína , Albuminas/química , Animais , Linhagem Celular Tumoral , Fluorescência , Neoplasias/terapia , Imagem Óptica , Fototerapia , Nanomedicina Teranóstica/métodos
15.
Small ; 18(18): e2200875, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35385220

RESUMO

Nonlinear elastic materials are significant for engineering and micromechanics. Droplets with the merits of easy-accessibility, diversity, and energy-absorption capability exhibit a variety of non-Hookean elastic behaviors. Herein, benefiting from the confinement of heterogeneous-wettable parallel plates, the non-Hookean mechanics of the droplet-based spring are systematically investigated. Experimental results and theoretical analysis reveal that the force generated by the spring varies nonlinearly with its deformation, and a force model is accordingly built to depict the mechanics of springs with different sized/numbered droplets and confined by different wettability patterns. Importantly, for the droplet-based spring, the droplet-plate contact area expands nonlinearly with the pressing force, which is employed to optimize the output performance of the droplet-based triboelectric nanogenerator to 226% compared with the control test. This finding deepens the understanding of the non-Hookean behavior of droplet-based springs, and sheds light on applications in energy harvesting, micromechanics, and miniature optic/electric devices.


Assuntos
Molhabilidade , Fenômenos Físicos
16.
Toxicol Appl Pharmacol ; 449: 116110, 2022 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-35688186

RESUMO

Protein phosphorylation is the most common type of post-translational modification where serine, threonine or tyrosine are reversibly bound to the phosphate group of ATP in a reaction catalyzed by protein kinases. Phosphorylation plays an important role in regulation of cell homeostasis, including but not limited to signal perception and transduction, gene expression and function of proteins. Protein phosphorylation happens on a fast time scale and represents an energy-efficient way for the cell to adapt to exposure to chemical stressors. To understand the cascade of cellular signaling induced by exposure to chemicals, we have exposed HepG2 cells to three chemicals with different modes of action, namely, caffeine, coumarin, and quercetin in a concentration and time response manner. Significantly upregulated and downregulated phosphosites were screened to analyze the activation/deactivation of signaling pathways by protein kinases. In total, 69, 44 and 12 signaling pathways were found enriched in caffeine, coumarin and quercetin treated cells, respectively, of which 9 pathways were co-enriched with 11 jointly responded kinases. Among identified co-responded kinases, CDK1, MAPK1 and MAPK3 play important roles in cell cycle and insulin signaling pathways. Quantitative phosphoproteomics can sensitively distinguish the effects of different chemicals on cells, allowing the assessment of chemical safety through changes in substrates and metabolic pathways at the cellular level, which is important for the development of non-animal approaches for chemical safety assessment.


Assuntos
Cafeína , Cumarínicos , Quercetina , Cafeína/farmacologia , Cumarínicos/farmacologia , Células Hep G2 , Humanos , Fosforilação , Proteínas Quinases/metabolismo , Proteômica , Quercetina/farmacologia
17.
Faraday Discuss ; 233(0): 190-205, 2022 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-34889342

RESUMO

Copper is the most widely used substrate for Li deposition and dissolution in lithium metal anodes, which is complicated by the formation of solid electrolyte interphases (SEIs), whose physical and chemical properties can affect Li deposition and dissolution significantly. However, initial Li nucleation and growth on bare Cu creates Li nuclei that only partially cover the Cu surface so that SEI formation could proceed not only on Li nuclei but also on the bare region of the Cu surface with different kinetics, which may affect the follow-up processes distinctively. In this paper, we employ in situ atomic force microscopy (AFM), together with X-ray photoelectron spectroscopy (XPS), to investigate how SEIs formed on a Cu surface, without Li participation, and on the surface of growing Li nuclei, with Li participation, affect the components and structures of the SEIs, and how the formation sequence of the two kinds of SEIs, along with Li deposition, affect subsequent dissolution and re-deposition processes in a pyrrolidinium-based ionic liquid electrolyte containing a small amount of water. Nanoscale in situ AFM observations show that sphere-like Li deposits may have differently conditioned SEI-shells, depending on whether Li nucleation is preceded by the formation of the SEI on Cu. Models of integrated-SEI shells and segmented-SEI shells are proposed to describe SEI shells formed on Li nuclei and SEI shells sequentially formed on Cu and then on Li nuclei, respectively. "Top-dissolution" is observed for both types of shelled Li deposits, but the integrated-SEI shells only show wrinkles, which can be recovered upon Li re-deposition, while the segmented-SEI shells are apparently top-opened due to mechanical stresses introduced at the junctions of the top regions and become "dead" SEIs, which forces subsequent Li nucleation and growth in the interstice of the dead SEIs. Our work provides insights into the impact mechanism of SEIs on the initial stage Li deposition and dissolution on foreign substrates, revealing that SEIs could be more influential on Li dissolution and that the spatial integration of SEI shells on Li deposits is important to improving the reversibility of deposition and dissolution cycling.

18.
Neurourol Urodyn ; 41(3): 765-776, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35170809

RESUMO

INTRODUCTION: Ketamine-induced cystitis (KIC) is a disease caused by ketamine that can cause lower urinary tract symptoms (LUTS). Its end-stage is bladder contracture, which is related to bladder fibrosis and poses a serious burden to patient lives. METHODS: We established a KIC model in female Sprague Dawley rats and verified bladder fibrosis in the model by Masson trichrome staining and western blot analysis. The bladders of the rats from the ketamine and control groups were used to perform transcriptome analysis. In particular, association analysis with metabolomics was also used to determine the potential mechanisms of ketamine-induced bladder fibrosis. RESULTS: A total of 685 differentially expressed messenger RNAs, 71 differentially expressed long noncoding RNAs, 23 differentially expressed microRNAs, and 68 differentially expressed circular RNAs were identified. We found that ribosome, Wnt signaling, vascular endothelial growth factor signaling, cytoskeleton organization, and cytoskeletal protein binding may be potential pathways in ketamine-induced bladder fibrosis as identified by Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses. In addition, the mitogen-activated protein kinase pathway appeared to be closely related to the development of ketamine-induced bladder fibrosis according to association analysis. CONCLUSIONS: In this study, using transcriptomic and correlation analyses of metabolomics, we identified pathways that may be potential targets for the prevention and treatment of ketamine-induced bladder fibrosis.


Assuntos
Cistite , Ketamina , Animais , Cistite/induzido quimicamente , Feminino , Fibrose , Perfilação da Expressão Gênica , Humanos , Ketamina/toxicidade , Masculino , Ratos , Ratos Sprague-Dawley , Transcriptoma , Bexiga Urinária/metabolismo , Fator A de Crescimento do Endotélio Vascular/efeitos adversos , Fator A de Crescimento do Endotélio Vascular/metabolismo
19.
Clin Lab ; 68(8)2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35975488

RESUMO

BACKGROUND: Ischemic stroke refers to ischemic necrosis or softening of limited brain tissue caused by ischemia and hypoxia due to impaired blood circulation in the brain. Ischemic stroke is a major classification of cerebrovascular disease, accounting for about 80% of patients with cerebrovascular disease in China, with a high rate of disability and death. Recently, miRNAs were reported to participate in ischemic stroke pathogenesis and development. In the study, we aimed to study the role and underlying mechanism of miR-641 in ischemic stroke. METHODS: Serum samples were extracted from acute ischemic stroke (AIS) patients and healthy controls. The oxygen-glucose deprivation/reoxygenation (OGD/R) method was used to treat SH-SY5Y cells to construct an ischemic stroke in vitro model. Real-time quantitative polymerase chain reaction (qRT-PCR) assay and western blot analysis were conducted to detect miR-641 and MCL-1 expressions. The targeted relationship between miR-641 and MCL-1 was confirmed by dual-luciferase reporter, RNA pull-down, and rescue assays. CCK-8, flow cytometry, and ELISA assays were performed to measure cell viability, apoptosis, and inflammation. The activation of the Wnt/ß-catenin pathway was verified by western blot assay. RESULTS: MiR-641 was increased while MCL-1 was decreased in serum samples from AIS patients, serving as highly-sensitive biomarkers in AIS diagnosis. After OGD/R treatment, SH-SY5Y cell viability, and MCL-1 expression were decreased, along with increased miR-641 expression, cell apoptosis, and inflammation. MiR-641 aggravated while MCL-1 mitigated OGD/R-triggered injury and inflammation in SH-SY5Y cells. MCL-1 was a downstream target of miR-641, which could be negatively regulated by miR-641. Finally, miR-641 exacerbated the progression of OGD/R-triggered SH-SY5Y cell injury via the MCL-1/Wnt/ß-catenin pathway. CONCLUSIONS: MiR-641 may be a novel therapeutic agent for ischemic stroke by modulating the MCL-1/Wnt/ß-catenin axis on neuronal damage in brain tissue in the ischemic region after ischemic stroke.


Assuntos
AVC Isquêmico , MicroRNAs , Proteína de Sequência 1 de Leucemia de Células Mieloides , Via de Sinalização Wnt , Apoptose/genética , Glucose/metabolismo , Humanos , Inflamação , AVC Isquêmico/genética , MicroRNAs/genética , Proteína de Sequência 1 de Leucemia de Células Mieloides/genética , Oxigênio , beta Catenina/genética
20.
Angew Chem Int Ed Engl ; 61(34): e202207255, 2022 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-35715387

RESUMO

Owing to unique alkyne-rich structure, graphdiyne (GDY) has been proven to be a superb support for anchoring metal catalysts. Herein we demonstrate a new role of GDY as the wettability modifier for enhanced hydrogenation catalysis. After loading a certain amount GDY nanospheres, the silica mesoporous channels become superaerophilic, which allows gaseous H2 to be directly stored inside, thus significantly increasing the H2 concentration around the palladium nanoparticles (NPs). At the same time, GDY nanospheres also alter the electronic structure of the Pd NPs via a strong d-π interaction. Combining these two roles of GDY, allows the hydrogenation of benzaldehyde to proceed under ambient H2 pressure in water, with an impressive 4.3-fold enhancement compared to the unmodified Pd/mSiO2 catalyst. This study demonstrates a new role of GDY in constructing wettability matched catalysts for gas-liquid-solid tri-phase reactions.

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