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1.
Proc Natl Acad Sci U S A ; 121(9): e2317435121, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38377211

RESUMO

Creating efficient catalysts for simultaneous H2O2 generation and pollutant degradation is vital. Piezocatalytic H2O2 synthesis offers a promising alternative to traditional methods but faces challenges like sacrificial reagents, harsh conditions, and low activity. In this study, we introduce a cobalt-loaded ZnO (CZO) piezocatalyst that efficiently generates H2O2 from H2O and O2 under ultrasonic (US) treatment in ambient aqueous conditions. The catalyst demonstrates exceptional performance with ~50.9% TOC removal of phenol and in situ generation of 1.3 mM H2O2, significantly outperforming pure ZnO. Notably, the CZO piezocatalyst maintains its H2O2 generation capability even after multiple cycles, showing continuous improvement (from 1.3 mM to 1.8 mM). This is attributed to the piezoelectric electrons promoting the generation of dynamic defects under US conditions, which in turn promotes the adsorption and activation of oxygen, thereby facilitating efficient H2O2 production, as confirmed by EPR spectrometry, XPS analysis, and DFT calculations. Moreover, the CZO piezocatalysts maintain outstanding performance in pollutant degradation and H2O2 production even after long periods of inactivity, and the deactivated catalyst due to metal ion dissolution could be rejuvenated by pH adjustment, offering a sustainable solution for wastewater purification.

2.
Proc Natl Acad Sci U S A ; 120(7): e2218813120, 2023 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-36745798

RESUMO

Efficient H2 harvesting from wastewater instead of pure water can minimize fresh water consumption, which is expected to solve the problem of water shortage in H2 production process and contribute to carbon neutrality in the environmental remediation, but the inevitable electron depletion caused by electron-consuming pollutants will result in an exhausted H2 evolution reaction (HER) performance. In this paper, by coupling piezocatalysis and advanced oxidation processes (AOPs) by a MoS2/Fe0/peroxymonosulfate (PMS) ternary system, extensive types of wastewater achieved considerable H2 generation, which exceeded the yield in pure water with synchronous advanced degradation of organic pollutants. In addition, profiting from the crucial bridging role of PMS, the H2 yield in nitrobenzene wastewater after the introduction of PMS-based AOPs increased 3.37-fold from 267.7 µmol·g-1·h-1 to 901.0 µmol·g-1·h-1 because the presence of PMS both thermodynamically benefited MoS2 piezocatalytic H2 evolution and eliminated the electron depletion caused by organic pollutants. By this way, the original repressed H2 evolution performance in substrate of wastewater not only was regained but even showed a significant enhancement than that in pure water (505.7 µmol·g-1·h-1). Additionally, the cyclonic piezoelectric reactor was preliminarily designed for future industrialization. This strategy provided a valuable path for the recycling of actual wastewater by fuel production and synchronous advanced treatment.

3.
Proc Natl Acad Sci U S A ; 120(29): e2305933120, 2023 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-37428912

RESUMO

Single-atom catalysts (SACs) are a promising area in environmental catalysis. We report on a bimetallic Co-Mo SAC that shows excellent performance in activating peroxymonosulfate (PMS) for sustainable degradation of organic pollutants with high ionization potential (IP > 8.5 eV). Density Functional Theory (DFT) calculations and experimental tests demonstrate that the Mo sites in Mo-Co SACs play a critical role in conducting electrons from organic pollutants to Co sites, leading to a 19.4-fold increase in the degradation rate of phenol compared to the CoCl2-PMS group. The bimetallic SACs exhibit excellent catalytic performance even under extreme conditions and show long-term activation in 10-d experiments, efficiently degrading 600 mg/L of phenol. Moreover, the catalyst has negligible toxicity toward MDA-MB-231, Hela, and MCF-7 cells, making it an environmentally friendly option for sustainable water treatment. Our findings have important implications for the design of efficient SACs for environmental remediation and other applications in biology and medicine.

4.
Proc Natl Acad Sci U S A ; 119(9)2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-35217599

RESUMO

Percolation theory has been widely used to study phase transitions in network systems. It has also successfully explained various macroscopic spreading phenomena across different fields. Yet, the theoretical frameworks have been focusing on direct interactions among nodes, while recent empirical observations have shown that indirect interactions are common in many network systems like social and ecological networks, among others. By investigating the detailed mechanism of both direct and indirect influence on scientific collaboration networks, here we show that indirect influence can play the dominant role in behavioral influence. To address the lack of theoretical understanding of such indirect influence on the macroscopic behavior of the system, we propose a percolation mechanism of indirect interactions called induced percolation. Surprisingly, our model exhibits a unique anisotropy property. Specifically, directed networks show first-order abrupt transitions as opposed to the second-order continuous transition in the same network structure but with undirected links. A mix of directed and undirected links leads to rich hybrid phase transitions. Furthermore, a unique feature of the nonmonotonic pattern is observed in network connectivities near the critical point. We also present an analytical framework to characterize the proposed induced percolation, paving the way to further understanding network dynamics with indirect interactions.

5.
Nano Lett ; 24(21): 6337-6343, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38742772

RESUMO

The bulk photovoltaic effect (BPVE) offers an interesting approach to generate a steady photocurrent in a single-phase material under homogeneous illumination, and it has been extensively investigated in ferroelectrics exhibiting spontaneous polarization that breaks inversion symmetry. Flexoelectricity breaks inversion symmetry via a strain gradient in the otherwise nonpolar materials, enabling manipulation of ferroelectric order without an electric field. Combining these two effects, we demonstrate active mechanical control of BPVE in suspended 2-dimensional CuInP2S6 (CIPS) that is ferroelectric yet sensitive to electric field, which enables practical photodetection with an order of magnitude enhancement in performance. The suspended CIPS exhibits a 20-fold increase in photocurrent, which can be continuously modulated by either mechanical force or light polarization. The flexoelectrically engineered photodetection device, activated by air pressure and without any optimization, possesses a responsivity of 2.45 × 10-2 A/W and a detectivity of 1.73 × 1011 jones, which are superior to those of ferroelectric-based photodetection and comparable to those of the commercial Si photodiode.

6.
Anal Chem ; 96(28): 11205-11215, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-38967035

RESUMO

Lipid nanoparticles (LNPs) are emerging as one of the most promising drug delivery systems. The long-circulating effect of intact LNPs (i-LNPs) is the key to efficacy and toxicity in vivo. However, the significant challenge is specific and sensitive detection of i-LNPs. Herein, a dual-recognition fluorescence enzyme-linked immunosorbent assay (DR-FELISA) was developed to directly isolate and detect i-LNPs by combining dual-recognition separation with a one-step signal amplification strategy. The microplates captured and enriched i-LNPs through antibody-antigen reaction. Dual-chol probes were spontaneously introduced into the lipid bilayer of captured i-LNPs, converting the detection of i-LNPs into the detection of double-cholesterol probes. Finally, the end of the dual-chol probes initiated the localized scaffolding autocatalytic DNA circuits (SADC) system for further signal amplification. The SADC system provides a sensitive and efficient amplifier through localized network structures and self-assembled triggers. Simultaneous recognition of i-LNPs surface PEG-lipid and lipid bilayer structures significantly eliminates interference from biological samples. i-LNPs were detected with high selectivity, ranging from 0.2 to 1.25 mg/mL with a limit of detection of 0.1 mg/mL. Moreover, this method allows the isolation and quantitative analysis of different formulations of i-LNPs in serum samples with a satisfactory recovery rate ranging from 94.8 to 116.3%. Thus, the DR-FELISA method provides an advanced platform for the exclusive and sensitive detection of i-LNPs, providing new insights for the study of the quality and intracorporal process of complex formulations.


Assuntos
DNA , Ensaio de Imunoadsorção Enzimática , Nanopartículas , Nanopartículas/química , DNA/química , Limite de Detecção , Lipídeos/química , Fluorescência , Catálise , Lipossomos
7.
Mol Cell Biochem ; 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38700746

RESUMO

Acute myeloid leukemia (AML) is a rare and heterogeneous disease. Over the past few decades, patient prognosis has improved with continuous improvements in treatment, but outcomes for some patients with primary drug resistance or relapse after treatment remain poor. Additional therapies to improve outcomes for these patients are urgently needed. FYB1 expression differs substantially between AML tissues and normal tissues. High FYB1 expression is correlated with poorer overall survival (OS), indicating that FYB1 may regulate AML progression. Therefore, understanding the effect of FYB1 on AML could improve the success rate of therapeutic approaches and prognosis for patients with AML. In this study, through analysis of large databases and both in vivo and in vitro experiments, we assessed the expression and role of FYB1 in AML and the relationship of FYB with patient prognosis. Downstream targets of the FYB1 gene were analyzed by RNA-seq. Database mining and in vitro experiments were used to further clarify the effect of the downstream target gelsolin-like actin-capping protein (CAPG) on AML cells and its relationship with patient prognosis. FYB1 expression was significantly higher in AML tissue and corresponded with a poor prognosis. FYB1 knockdown inhibited AML cell proliferation, promoted cell apoptosis, reduced cell adhesion capability and significantly reduced the tumor formation rate in mice. In addition, FYB1 knockdown induced a notable decrease in CAPG expression. The suppression of CAPG significantly inhibited cell proliferation and increased cell apoptosis. The conclusions of this study underscore the pivotal role of the FYB1/CAPG axis in promoting AML. We propose that the FYB1/CAPG axis could serve as a new thread in the development of therapeutic strategies for AML.

8.
Bioorg Chem ; 148: 107488, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38797066

RESUMO

Progressive loss of dopaminergic neurons leads to the depletion of the striatal neurotransmitter dopamine, which is the main cause of Parkinson's disease (PD) motor symptoms. Simultaneous inhibition of the two key dopamine metabolic enzymes, catechol-O-methyltransferase (COMT) and monoamine oxidase B (MAO-B), could potentially be a breakthrough in achieving clinical efficacy. Representative compound C12 exhibits good COMT inhibitory activity (IC50 = 0.37 µM), metal chelation ability, and BBB permeability. Furthermore, results from in vivo biological activity evaluations indicate that C12 can improve dopamine levels and ameliorate MPTP-induced PD symptoms in mice. Preliminary in vivo and in vitro study results highlight the potential of compound C12 in PD treatment.


Assuntos
Dopamina , Inibidores da Monoaminoxidase , Monoaminoxidase , Doença de Parkinson , Animais , Camundongos , Dopamina/metabolismo , Relação Estrutura-Atividade , Monoaminoxidase/metabolismo , Estrutura Molecular , Inibidores da Monoaminoxidase/farmacologia , Inibidores da Monoaminoxidase/química , Inibidores da Monoaminoxidase/síntese química , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/metabolismo , Catecol O-Metiltransferase/metabolismo , Camundongos Endogâmicos C57BL , Masculino , Inibidores de Catecol O-Metiltransferase/farmacologia , Inibidores de Catecol O-Metiltransferase/química , Inibidores de Catecol O-Metiltransferase/síntese química , Humanos , Relação Dose-Resposta a Droga , Antiparkinsonianos/farmacologia , Antiparkinsonianos/química , Antiparkinsonianos/síntese química , Antiparkinsonianos/uso terapêutico
9.
J Reprod Dev ; 2024 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-39010238

RESUMO

Calcium ions (Ca2+) play crucial roles in sperm motility and fertilization. The copine (CPNE) family comprises several Ca2+-dependent phospholipid-binding proteins. Of these, CPNE1 is extensively expressed in mammalian tissues; however, its precise role in testicular development and spermatogenesis is yet to be fully characterized. In this study, we used proteomics to analyze testicular biopsies and found that levels of CPNE1 were significantly reduced in patients with non-obstructive azoospermia (defective spermatogenesis) compared to those in patients with obstructive azoospermia (physiological spermatogenesis). In mice, CPNE1 is expressed at various stages of germ cell development and is associated with the Golgi apparatus. Ultimately, CPNE1 is expressed in the flagella of mature sperms. To further examine the role of CPNE1, we developed a Cpne1 knockout mouse model. Analysis showed that the loss of Cpne1 did not impair testicular development, spermatogenesis, or sperm morphology and motility in physiological conditions. When treated with gadolinium (III) chloride or 2-aminoethoxydiphenyl borate, known inhibitors of store-operated Ca2+ entry, Ca2+ signals and sperm motility were significantly compromised in wild-type mice; however, both mechanisms were conserved in KO mice. These results suggested that CPNE1 is dispensable for testicular development, spermatogenesis or sperm motility in physiological conditions. In addition, CPNE1 may represent a target of Ca2+ channel inhibitors and may therefore be implicated in the regulation of Ca2+ signaling and sperm motility.

10.
Anal Chem ; 95(34): 12893-12902, 2023 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-37589895

RESUMO

Genotoxic impurities (GTIs) occurred in drugs, and food and environment pose a threat to human health. Accurate and sensitive evaluation of GTIs is of significance. Ames assay is the existing gold standard method. However, the pathogenic bacteria model lacks metabolic enzymes and requires mass GTIs, leading to insufficient safety, accuracy, and sensitivity. Whole-cell microbial sensors (WCMSs) can use normal strains to simulate the metabolic environment, achieving safe, sensitive, and high-throughput detection and evaluation for GTIs. Here, based on whether GTIs causing DNA alkylation required metabolic enzymes or not, two DNA repair-responsive engineered WCMS systems were constructed including Escherichia coli-WCMS and yeast-WCMS. A DNA repair-responsive promoter as a sensing element was coupled with an enhanced green fluorescent protein as a reporter to construct plasmids for introduction into WCMS. The ada promoter was screened out in the E. coli-WCMS, while the MAG1 promoter was selected for the yeast-WCMS. Different E. coli and yeast strains were modified by gene knockout and mutation to eliminate the interference and enhance the GTI retention in cells and further improved the sensitivity. Finally, GTI consumption of WCMS for the evaluation of methyl methanesulfonate (MMS) and nitrosamines was decreased to 0.46-8.53 µg and 0.068 ng-2.65 µg, respectively, decreasing 2-3 orders of magnitude compared to traditional methods. This study provided a novel approach to measure GTIs with different DNA damage pathways at a molecular level and facilitated the high-throughput screening and sensitive evaluation of GTIs.


Assuntos
Ensaios de Triagem em Larga Escala , Saccharomyces cerevisiae , Humanos , Saccharomyces cerevisiae/genética , Escherichia coli/genética , Reparo do DNA , Dano ao DNA
11.
Anal Chem ; 95(15): 6312-6322, 2023 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-37000898

RESUMO

The γH2AX is a type of confined target in nuclei which is highly expressed around the damaged DNA during genotoxicity and has therefore been identified as a marker of genotoxicity. Convenient and intuitive in situ real-time detection of γH2AX is crucial for an accurate assessment of genotoxicity. Selective and nondestructive surface-enhanced Raman spectroscopy (SERS) is suitable to achieve this goal. However, the detection of substances in the nucleus by SERS is still limited due to the contradiction of probes between the nuclei entry efficiency and signal enhancement. This study utilized the characteristics of γH2AX as a confined target and constructed a γH2AX immunosensor based on gold nanoprobes with a small size (15 nm), which was modified with the TAT nuclear targeting peptide to ensure high nuclei entry efficiency. Once DNA damage was induced, the local overexpression of γH2AX further recruited the probe through immune recognition, so that hot spots could be assembled in situ to generate strong Raman signals, which were applied to evaluate the genotoxicity of drug impurities. This study proposed a novel SERS detection strategy, characterized by confined target-induced size conversion and hot spot formation, for in situ real-time analysis of intranuclear targets at the single-living-cell level, which intelligently simplified the structure of SERS probes and the operation process.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Imunoensaio , Análise Espectral Raman/métodos , Ouro/química , Nanopartículas Metálicas/química
12.
Cancer Immunol Immunother ; 72(9): 3079-3095, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37351605

RESUMO

Photodynamic therapy (PDT) is an emerging clinical treatment that is expected to become an important adjuvant strategy for the immunotherapeutic cancer treatment. Recently, numerous works have reported combination strategies. However, clinical data showed that the anti-tumor immune response of PDT was not lasting though existing. The immune activation effect will eventually turn to immunosuppressive effect and get aggravated at the late stage post-PDT. So far, the mechanism is still unclear, which limits the design of specific correction strategies and further development of PDT. Several lines of evidence suggest a role for TGF-ß1 in the immunosuppression associated with PDT. Herein, this study systematically illustrated the dynamic changes of immune states post-PDT within the tumor microenvironment. The results clearly demonstrated that high-light-dose PDT, as a therapeutic dose, induced early immune activation followed by late immunosuppression, which was mediated by the activated TGF-ß1 upregulation. Then, the mechanism of PDT-induced TGF-ß1 accumulation and immunosuppression was elucidated, including the ROS/TGF-ß1/MMP-9 positive feedback loop and CD44-mediated local amplification, which was further confirmed by spatial transcriptomics, as well as by the extensive immune inhibitory effect of local high concentration of TGF-ß1. Finally, a TGF-ß blockade treatment strategy was presented as a promising combinational strategy to reverse high-light-dose PDT-associated immunosuppression. The results of this study provide new insights for the biology mechanism and smart improvement approaches to enhance tumor photodynamic immunotherapy.


Assuntos
Neoplasias , Fotoquimioterapia , Humanos , Fator de Crescimento Transformador beta1 , Fotoquimioterapia/métodos , Terapia de Imunossupressão , Neoplasias/tratamento farmacológico , Fator de Crescimento Transformador beta , Linhagem Celular Tumoral , Microambiente Tumoral
13.
Bioorg Chem ; 139: 106702, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37390634

RESUMO

The selective AChE inhibitor donepezil has been approved by the FDA as a first-line drug for the treatment of mild to moderate AD. However, many peripheral side effects were observed in patients taking donepezil. Our main objective here is to provide insight into the opportunities and challenges associated with development of AChE inhibitors with high brain exposure and low peripheral side effects. In this study, we have for the first time revealed a series of novel thiazole salt AChE inhibitors, which exhibit a nanomolar inhibitory effect on human AChE. We further developed thiamine disulfide prodrugs based on optimized thiazole salt AChE inhibitors, which are reduced in the brain to form thiazole salt AChE inhibitors. In vivo experiments have confirmed that the representative prodrug Tap4 (i.p., 10 mg/kg) can be converted into the thiazole salt AChE inhibitor Tat2 and shows high brain exposure, reaching 500 ng/g. Further, the inhibitory effect of the prodrug Tap4 on AChE is obviously stronger in the brain than that on intestinal AChE of ICR mice. Our study provides a possible basis for centrally targeted thiazole salt inhibitors in the treatment of neurodegenerative diseases.


Assuntos
Doença de Alzheimer , Pró-Fármacos , Camundongos , Animais , Humanos , Donepezila/farmacologia , Tiazóis/farmacologia , Tiazóis/uso terapêutico , Inibidores da Colinesterase/farmacologia , Inibidores da Colinesterase/uso terapêutico , Pró-Fármacos/farmacologia , Pró-Fármacos/uso terapêutico , Camundongos Endogâmicos ICR , Encéfalo/metabolismo , Acetilcolinesterase/metabolismo , Doença de Alzheimer/tratamento farmacológico
14.
Bioorg Chem ; 136: 106545, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37087849

RESUMO

Tetracyclic oxindole alkaloids (TOAs), main active ingredients of Uncaria rhynchophylla (UR), has inspired the interest of pharmacologists and chemists because of its great potential in the treatment of the diseases of the nervous system and cardiovascular system and its special spirooxindole scaffold, but the biosynthetic pathway of this compounds is still unknown. In this work, the metabolomics and transcriptomics of hook, leaf and stem of UR were analyzed, and 31 alkaloids and 47,423 unigenes were identified, as well as the relative contents of these alkaloids were evaluated. Based on the above results and literatures, a proposal biosynthetic pathway for TOAs was devised. Furthermore, three unigenes were suggested mediating the biosynthesis of TOAs through the integrated analysis of metabolomics and transcriptomics, and three enzymes, tryptophan decarboxylase, strictosidine synthase and strictosidine-ß-d-glucosidase, were identified as important catalytic enzymes for the synthesis of tryptamine, strictosidine (7) and 4,21-dehydrogeissochizine, respectively, which are considered as the important precursors of TOAs.


Assuntos
Alcaloides , Uncaria , Oxindóis , Alcaloides/metabolismo , Folhas de Planta/metabolismo
15.
BMC Pediatr ; 23(1): 431, 2023 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-37641081

RESUMO

INTRODUCTION: Mycobacterium abscessus is a rapidly growing mycobacterium commonly identified in adults with underlying pulmonary diseases but is rarely observed in children. A better understanding of this pathogen in children is essential. CASE PRESENTATION: We report the case of a 49-month-old female child without previous underlying pulmonary diseases but with acute lymphoblastic leukemia (ALL). The patient was complicated with pneumonia during chemotherapy, which was primarily characterized by spontaneous pneumomediastinum and subcutaneous emphysema on chest computed tomography (CT). M. abscessus sequences were detected by metagenomic next-generation sequencing in bronchoalveolar lavage fluid. With mechanical ventilation, closed thoracic drainage, and anti-infective therapy for 6 months, the patient's infection was controlled. The patient completed 2.5 years of treatment for ALL, and the drugs were discontinued. The patient currently remains in complete hematologic remission. DISCUSSION: We reviewed the literature on 33 children with M. abscessus pulmonary disease. These children mostly had underlying immunodeficiency. Chest CT most often showed nodular shadows, consolidation, and bronchiectasis. Spontaneous pneumomediastinum and subcutaneous emphysema were not reported as major manifestations. CONCLUSION: Spontaneous pneumomediastinum and subcutaneous emphysema were our patient's main characteristics on chest CT, and this study enriches the knowledge regarding possible imaging changes in M. abscessus pulmonary disease in children. This case report reflects good clinical experience in maintaining the balance between chemotherapy and anti-infective therapy in childhood ALL.


Assuntos
Pneumopatias , Enfisema Mediastínico , Mycobacterium abscessus , Leucemia-Linfoma Linfoblástico de Células Precursoras , Enfisema Subcutâneo , Adulto , Criança , Feminino , Humanos , Pré-Escolar , Enfisema Mediastínico/diagnóstico por imagem , Enfisema Mediastínico/etiologia , Enfisema Subcutâneo/diagnóstico por imagem , Enfisema Subcutâneo/etiologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/complicações
16.
Chem Biodivers ; 20(1): e202200822, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36527339

RESUMO

The traditional Chinese medicine of fermented medicine may be under the involvement of multiple strains and the interaction between these microorganisms. Liu Shenqu (Massa Medicata Fermentata, MMF) is one of the most widely used fermented medicines, whose potential processing mechanism is still unclear. In this work, UPLC/MS and GNPS methods were employed to rapidly predict chemical compositions in MMF. Moreover, the dynamic changes of strains, chemical compositions and anti-inflammatory activity of MMF during fermentation process were investigated, and subsequently strains-chemical compositions-efficacy interactions were revealed by Pearson correlation analysis and partial least squares regression (PLSR) analysis. As a result, 24 components were identified, and the potential strains including Bacillus, Burkholderia_Caballeronia_Paraburkholderia, Enterobacter, Aspergillus heterocaryoticus, Rhizopus arrhizus, Kazachstania bulderi, which related to the production of anti-inflammatory active ingredients were exposed. These results demonstrated chemical compositions-strains-efficacy interactions during fermentation of MMF, and provide reference for the exploration of the processing mechanism of MMF.


Assuntos
Medicamentos de Ervas Chinesas , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/química , Medicina Tradicional Chinesa/métodos , Anti-Inflamatórios/farmacologia
17.
Bioorg Chem ; 127: 106004, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35843015

RESUMO

Cardiac glycosides (CGs) show potential broad-spectrum antiviral activity by targeting cellular host proteins. Herein are reported the isolation of five new (1-5) and eight known (7-13) CGs from the roots of Streblus asper Lour. Of these compounds 1 and 7 exhibited inhibitory action against EBV early antigen (EA) expression, with half-maximal effective concentration values (EC50) being less than 60 nM, and they also showed selectivity, with selectivity index (SI) values being 56.80 and 103.17, respectively. Preliminary structure activity relationships indicated that the C-10 substituent, C-5 hydroxy groups, and C-3 sugar unit play essential roles in the mediation of the inhibitory activity of CGs against EBV. Further enzyme experiments demonstrated that these compounds might inhibit ion pump function and thereby change the intracellular signal transduction pathway by binding to Na+/K+-ATPase, as validated by simulated molecular docking. This study is the first report that CGs can effectively limit EBV lytic replication, and the observations made in this study may be of value for lead compound development.


Assuntos
Glicosídeos Cardíacos , Infecções por Vírus Epstein-Barr , Moraceae , Glicosídeos Cardíacos/química , Infecções por Vírus Epstein-Barr/tratamento farmacológico , Herpesvirus Humano 4/metabolismo , Simulação de Acoplamento Molecular , Moraceae/química
18.
Mikrochim Acta ; 189(8): 293, 2022 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-35881205

RESUMO

CuO nanorods bearing Au nanoparticles (Au/CuO nanocomposites) were prepared by a solution-phase synthesis and exhibited efficient hydroquinone (HQ)-oxidase activity with good specificity. The Au/CuO nanocomposites effectively catalyzed the oxidation of colorless HQ to brown benzoquinone with an absorbance maximum at 376 nm but did not catalyze the conversions of catechol or resorcinol. Kinetic studies indicated that the Au/CuO nanocomposites exhibited a strong affinity for HQ, with a Michaelis-Menten constant of Km = 0.33 mM. Owing to the high catalytic activity and specificity, a strong color was observed at low concentrations of HQ. Quantitative measurement of HQ was performed via colorimetric analysis, which yielded a detection limit of 3 µM with a linear range of 5-200 µM. This colorimetric sensor was successfully applied to an HQ assay of real water samples with satisfactory results.


Assuntos
Nanopartículas Metálicas , Nanocompostos , Colorimetria/métodos , Cobre , Ouro , Hidroquinonas , Cinética
19.
Sensors (Basel) ; 22(21)2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36366075

RESUMO

Automated inspection technology based on computer vision is now widely used in the manufacturing industry with high speed and accuracy. However, metal parts always appear in high gloss or shadow on the surface, resulting in the overexposure of the captured images. It is necessary to adjust the light direction and view to keep defects out of overexposure and shadow areas. However, it is too tedious to adjust the position of the light direction and view the variety of parts' geometries. To address this problem, we design a photometric-stereo-based defect detection system (PSBDDS), which combines the photometric stereo with defect detection to eliminate the interference of highlights and shadows. Based on the PSBDDS, we introduce a photometric-stereo-based defect detection framework, which takes images captured in multiple directional lights as input and obtains the normal map through the photometric stereo model. Then, the detection model uses the normal map as input to locate and classify defects. Existing learning-based photometric stereo methods and defect detection methods have achieved good performance in their respective fields. However, photometric stereo datasets and defect detection datasets are not sufficient for training and testing photometric-stereo-based defect detection methods, thus we create a photometric stereo defect detection (PSDD) dataset using our PSBDDS to eliminate gaps between learning-based photometric stereo and defect detection methods. Furthermore, experimental results prove the effectiveness of the proposed PSBBD and PSDD dataset.


Assuntos
Algoritmos , Fotogrametria , Fotogrametria/métodos , Fotometria
20.
Angew Chem Int Ed Engl ; 61(42): e202209542, 2022 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-35909082

RESUMO

The universal limit on the pH conditions is disturbing peroxymonosulfate (PMS)-triggered high-valent iron-oxo systems in environmental applications. Here, we propose for the first time the construction of a neutral microenvironment on the surface of Zn-Fe layered double hydroxide (ZnFe-LDH) by using the amphoteric properties of zinc hydroxide, which continuously generates ≡FeIV =O over a wide pH range of 3.0-11.0 in activating PMS. The ≡Zn(OH)2 moiety offers a neutral microenvironment at the phase interface, which mitigates the self-decomposition of ≡FeIV =O by protons and the hydrolysis reaction of iron by hydroxyl groups, which is supported by the Mossbauer spectra, density functional theory calculations and designed experiments. Consequently, ZnFe-LDH/PMS can satisfy the stability in long-term experiments, selectivity under conditions with high salinity or natural organic matter and efficient treatment of actual wastewater.

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