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1.
Proc Natl Acad Sci U S A ; 119(12): e2118709119, 2022 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-35290128

RESUMO

Triterpenoids are biologically active metabolites synthesized from a common linear precursor catalyzed by 2,3-oxidosqualene cyclases (OSCs) to form diverse triterpenoid skeletons. OSCs corresponding to many discovered triterpene alcohols in nature have not been functionally and mechanistically characterized due to the diversity of chemical structures and complexity of the cyclization mechanism. We carried out a genome-wide investigation of OSCs from Avena strigosa and discovered two triterpene synthases, namely, AsHS1 and AsHS2, using a Nicotiana benthamiana expression system. These synthases produce hopenol B and hop-17(21)-en-3ß-ol, which are components of surface wax in oat panicles and sheathes, respectively. We demonstrated that substitutions of two to three amino acid residues in AsHS1 with corresponding residues from AsHS2 allowed it to be completely converted into a hop-17(21)-en-3ß-ol synthase. AsHS2 mutants with a substitution at site 410 could synthesize hopenol B alone or mixed with a side product isomotiol. The combined quantum mechanics and molecular mechanics calculation demonstrated that the side chain size of the residue at site 410 regulated the relative orientations between the hopyl C22 cation and Phe257, leading to a difference in deprotonation positions through providing or not providing cation­π interaction between the aromatic ring of F257 and the carbocation intermediate. A similar mechanism could be applied to a hopenol B synthase from a dicotyledonous plant Aquilegia. This study provided mechanistic insight into triterpenoid synthesis and discovered key amino acid residues acting on hydride transfer and a deprotonation site to differentiate between hopane-type scaffolds in diverse plant species.


Assuntos
Transferases Intramoleculares , Triterpenos , Avena/genética , Transferases Intramoleculares/genética , Plantas
2.
J Org Chem ; 89(14): 10180-10196, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-38963050

RESUMO

Presented herein are novel syntheses of CF3-isoquinolinones and imidazole fused CF3-isoquinolinones based on the cascade reactions of 2-aryloxazolines with trifluoromethyl imidoyl sulfoxonium ylides. The formation of CF3-isoquinolinone involves an intriguing cascade process including oxazolinyl group-assisted aryl alkylation through C(sp2)-H bond metalation, carbene formation, migratory insertion, and proto-demetalation followed by intramolecular condensation and water-promoted oxazolinyl ring-scission. With this method, the isoquinolinone scaffold tethered with valuable functional groups was effectively constructed. By taking advantage of the functional groups embedded therein, the products thus obtained could be readily transformed into imidazole-fused CF3-isoquinolinones or coupled with some clinical drugs to furnish hybrid compounds with potential applications in drug development. In general, the developed protocols feature expeditious and convenient formation of valuable CF3-heterocyclic skeletons, broad substrate scope, and ready scalability. In addition, studies on the activity of selected products against some human cancer cell lines demonstrated their potential as lead compounds for the development of novel anticancer drugs.

3.
Lipids Health Dis ; 23(1): 220, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39039525

RESUMO

BACKGROUND: Proprotein convertase subtilisins/kexin 6 (PCSK6) polymorphisms have been shown to be associated with atherosclerosis progression. This research aimed to evaluate the relationship of PCSK6 rs1531817 polymorphisms with coronary stenosis and the prognosis in premature myocardial infarction (PMI) patients. METHODS: This prospective cohort analysis consecutively included 605 PMI patients who performed emergency percutaneous coronary intervention (PCI) at Tianjin Chest Hospital sequentially between January 2017 and August 2022, with major adverse cardiovascular events (MACEs) as the outcome. Analyses assessed the relationships among PCSK6 rs1531817 polymorphism, Gensini score (GS), triple vessel disease (TVD), and MACEs. RESULTS: 92 (16.8%) patients experienced MACEs with an average follow-up of 25.7 months. Logistic analysis revealed that the PCSK6 rs1531817 CA + AA genotype was an independent protective factor against high GS and TVD. Cox analysis revealed that the PCSK6 rs1531817 CA + AA genotype was an independent protective factor against MACEs. The mediation effect results showed that apolipoprotein A1/apolipoprotein B (ApoA1/ApoB) partially mediated the association between PCSK6 rs1531817 polymorphism and coronary stenosis and that total cholesterol/high-density lipoprotein (TC/HDL) and TVD partially and in parallel mediated the association between the PCSK6 rs1531817 polymorphism and MACEs. CONCLUSION: Patients with the PCSK6 CA + AA genotype have milder coronary stenosis and a better long-term prognosis; according to the mediation model, ApoA1/ApoB and TC/HDL partially mediate. These results may provide a new perspective on clinical therapeutic strategy for anti-atherosclerosis and improved prognosis in PMI patients.


Assuntos
Estenose Coronária , Infarto do Miocárdio , Polimorfismo de Nucleotídeo Único , Humanos , Feminino , Masculino , Estudos Prospectivos , Infarto do Miocárdio/genética , Pessoa de Meia-Idade , Prognóstico , Estenose Coronária/genética , Adulto , Apolipoproteína A-I/genética , Intervenção Coronária Percutânea , Serina Endopeptidases/genética , Genótipo , Apolipoproteína B-100/genética , Predisposição Genética para Doença
4.
Int J Mol Sci ; 24(3)2023 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-36768882

RESUMO

Gametogenesis is an essential step for malaria parasite transmission and is activated in mosquito by signals including temperature drop, pH change, and mosquito-derived xanthurenic acid (XA). Recently, a membrane protein gametogenesis essential protein 1 (GEP1) was found to be responsible for sensing these signals and interacting with a giant guanylate cyclase α (GCα) to activate the cGMP-PKG-Ca2+ signaling pathway for malaria parasite gametogenesis. However, the molecular mechanisms for this process remain unclear. In this study, we used AlphaFold2 to predict the structure of GEP1 and found that it consists of a conserved N-terminal helical domain and a transmembrane domain that adopts a structure similar to that of cationic amino acid transporters. Molecular docking results showed that XA binds to GEP1 via a pocket similar to the ligand binding sites of known amino acid transporters. In addition, truncations of this N-terminal sequence significantly enhanced the expression, solubility, and stability of GEP1. In addition, we found that GEP1 interacts with GCα via its C-terminal region, which is interrupted by mutations of a few conserved residues. These findings provide further insights into the molecular mechanism for the XA recognition by GEP1 and the activation of the gametogenesis of malaria parasites through GEP1-GCα interaction.


Assuntos
Malária , Parasitos , Animais , Guanilato Ciclase/metabolismo , Parasitos/metabolismo , Simulação de Acoplamento Molecular , Transdução de Sinais , Gametogênese , GMP Cíclico/metabolismo , Malária/parasitologia
5.
Molecules ; 28(4)2023 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-36838854

RESUMO

Supported Pt-based catalysts have been identified as highly selective catalysts for CO oxidation, but their potential for applications has been hampered by the high cost and scarcity of Pt metals as well as aggregation problems at relatively high temperatures. In this work, nanorod structured (TiO2-Pt)/CeO2 catalysts with the addition of 0.3 at% Pt and different atomic ratios of Ti were prepared through a combined dealloying and calcination method. XRD, XPS, SEM, TEM, and STEM measurements were used to confirm the phase composition, surface morphology, and structure of synthesized samples. After calcination treatment, Pt nanoparticles were semi-inlayed on the surface of the CeO2 nanorod, and TiO2 was highly dispersed into the catalyst system, resulting in the formation of (TiO2-Pt)/CeO2 with high specific surface area and large pore volume. The unique structure can provide more reaction path and active sites for catalytic CO oxidation, thus contributing to the generation of catalysts with high catalytic activity. The outstanding catalytic performance is ascribed to the stable structure and proper TiO2 doping as well as the combined effect of Pt, TiO2, and CeO2. The research results are of importance for further development of high catalytic performance nanoporous catalytic materials.


Assuntos
Nanopartículas , Nanotubos , Oxirredução , Catálise
6.
Biochem Biophys Res Commun ; 620: 173-179, 2022 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-35803173

RESUMO

Separase is a giant cysteine protease and has multiple crucial functions. The most well-known substrate of separase is the kleisin subunit of cohesin, the cleavage of which triggers chromosome segregation during cell division (Uhlmann et al., 1999; Kamenz and Hauf, 2016) [1,2]. Recently, separase has also been found to cleave MCL-1 or BCL-XL proteins to trigger apoptosis (Hellmuth and Stemmann, 2020) [3]. Although substrate recognition through a short sequence right upstream of the cleavage site is well established, recent studies suggested that sequence elements outside this minimum cleavage site are required for optimal cleavage activity and specificity (Rosen et al., 2019; Uhlmann et al., 2000) [4,5]. However, the sequences and their underlying mechanism are largely unknown. To further explore the substrate determinants and recognition mechanism, we carried out sequence alignments and found a conserved motif downstream of the cleavage site in budding yeast. Using Alphafold2 and molecular dynamics simulations, we found this motif is recognized by separase in a conserved cleft near the binding groove of its inhibitor securin. Their binding is mutually exclusive and requires conformation changes of separase. These findings provide deeper insights into substrate recognition and activation of separase, and paved the way for discovering more substrates of separase.


Assuntos
Saccharomyces cerevisiae , Saccharomycetales , Proteínas de Ciclo Celular/metabolismo , Segregação de Cromossomos , Endopeptidases/metabolismo , Simulação de Dinâmica Molecular , Saccharomyces cerevisiae/metabolismo , Saccharomycetales/metabolismo , Securina/química , Securina/genética , Securina/metabolismo , Separase/genética
7.
Nanotechnology ; 30(23): 235402, 2019 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-30743256

RESUMO

In this work, NiCo2S4 nanoparticles for supercapacitors are successfully synthesized with a top-down strategy, using a novel dealloying method with an ion exchange reaction. The surface morphology and x-ray diffraction investigations demonstrated that NiCo2S4 nanoparticles are interconnected by ligaments of the synthesized sample. The dealloyed NiCo2S4 shows an enhanced electrochemical performance of about 1132.5 F g-1 at 0.5 A g-1; kinetic analysis implies a surface-controlled contribution from NiCo2S4 (53.86% capacitive contributions). Notably, the NiCo2S4//AC (active carbon) device displays a comparatively high energy density (22.83 Wh kg-1), maximum power density (1327.1 W kg-1) and superior cycling performance (capacitance retention of 108% after 30 000 cycles).

8.
Angew Chem Int Ed Engl ; 57(35): 11257-11261, 2018 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-29998625

RESUMO

Heterogeneous metal interfaces play a key role in determining the mechanism and performance of catalysts. However, in situ characterization of such interfaces at the molecular level is challenging. Herein, two model interfaces, Pd and Pt overlayers on Au single crystals, were constructed. The electronic structures of these interfaces as well as effects of crystallographic orientation on them were analyzed by shell-isolated nanoparticle-enhanced Raman spectroscopy (SHINERS) using phenyl isocyanide (PIC) as a probe molecule. A clear red shift in the frequency of the C≡N stretch (νNC ) was observed, which is consistent with X-ray photoelectron spectroscopy (XPS) data and indicates that the ultrathin Pt and Pd layers donate their free electrons to the Au substrates. Furthermore, in situ electrochemical SHINERS studies showed that the electronic effects weaken Pt-C/Pd-C bonds, leading to improved surface activity towards CO electrooxidation.

9.
Analyst ; 141(12): 3925, 2016 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-27082242

RESUMO

Correction for 'Shell-isolated nanoparticle-enhanced Raman spectroscopy study of the adsorption behaviour of DNA bases on Au(111) electrode surfaces' by Bao-Ying Wen et al., Analyst, 2016, DOI: 10.1039/c6an00180g.

10.
Analyst ; 141(12): 3731-6, 2016 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-27001527

RESUMO

For the first time, we used the electrochemical shell-isolated nanoparticle-enhanced Raman spectroscopy (EC-SHINERS) technique to in situ characterize the adsorption behaviour of four DNA bases (adenine, guanine, thymine, and cytosine) on atomically flat Au(111) electrode surfaces. The spectroscopic results of the various molecules reveal similar features, such as the adsorption-induced reconstruction of the Au(111) surface and the drastic Raman intensity reduction of the ring breathing modes after the lifting reconstruction. As a preliminary study of the photo-induced charge transfer (PICT) mechanism, the in situ spectroscopic results obtained on single crystal surfaces are excellently illustrated with electrochemical data.


Assuntos
DNA/química , Ouro , Nanopartículas , Análise Espectral Raman , Adsorção , Eletrodos
11.
Chirality ; 28(8): 612-7, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27428019

RESUMO

This study discusses the choice of different simplified models used in computations of electronic circular dichroism (ECD) spectra and other chiroptical characteristics used to determine the absolute configuration (AC) of the complex natural product sibiricumin A. Sections of molecules containing one chiral center with one near an aromatic group have large effects on the ECD spectra. Conversely, when the phenyl group is present on a substituent without a nonstereogenic center, removal of this section will have little effect on ECD spectra. However, these nonstereogenic-center-containing sections have large effects on calculated optical rotations (OR) values since the OR value is more sensitive to the geometries of sections in a molecule. In this study, the wrong AC of sibiricumin A was reassigned as (7R,8S,1'R,7'R,8'S)-. Chirality 28:612-617, 2016. © 2016 Wiley Periodicals, Inc.


Assuntos
Lignanas/química , Modelos Moleculares , Compostos de Espiro/química , Dicroísmo Circular , Estereoisomerismo
12.
Apoptosis ; 20(9): 1229-41, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26049256

RESUMO

In this study, we investigated the anticancer activity of icariin (ICA) against human lung adenocarcinoma cells in vitro and in vivo and explored the role of endoplasmic reticulum (ER) stress (ERS) signaling in this process. ICA treatment resulted in a dose- and time-dependent decrease in the viability of human lung adenocarcinoma A549 cells. Additionally, ICA exhibited potent anticancer activity, as evidenced by reductions in A549 cell adhesion, migration and intracellular glutathione (GSH) levels and increases in the apoptotic index, Caspase 3 activity, and reactive oxygen species. Furthermore, ICA treatment increased the expression of ERS-related molecules (p-PERK, ATF6, GRP78, p-eIF2α, and CHOP), up-regulated the apoptosis-related protein PUMA and down-regulated the anti-apoptosis-related protein Bcl2. The down-regulation of ERS signaling using PERK siRNA desensitized lung adenocarcinoma cells to ICA treatment, whereas the up-regulation of ERS signaling using thapsigargin (THA) sensitized lung adenocarcinoma cells to ICA treatment. Additionally, ICA inhibited the growth of human lung adenocarcinoma A549 cell xenografts by increasing the expression of ERS-related molecules (p-PERK and CHOP), up-regulating PUMA, and down-regulating Bcl2. These data indicate that ICA is a potential inhibitor of lung adenocarcinoma cell growth by targeting ERS signaling and suggest that the activation of ERS signaling may represent a novel therapeutic intervention for lung adenocarcinoma.


Assuntos
Adenocarcinoma/metabolismo , Antineoplásicos/farmacologia , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Flavonoides/farmacologia , Neoplasias Pulmonares/metabolismo , Adenocarcinoma de Pulmão , Animais , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/metabolismo , Caspase 3/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Chaperona BiP do Retículo Endoplasmático , Inibidores Enzimáticos/farmacologia , Glutationa/metabolismo , Xenoenxertos , Humanos , Masculino , Camundongos Nus , RNA Interferente Pequeno/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Tapsigargina/farmacologia
13.
Artigo em Inglês | MEDLINE | ID: mdl-38683422

RESUMO

BACKGROUND: In recent years, 5-Methoxytryptophan (5-MTP) has been identified as an endothelial factor with vaso-protective and anti-inflammatory properties. METHODS: In this prospective cohort study, a total of 407 patients with acute myocardial infarction (AMI) who underwent percutaneous coronary intervention (PCI) successfully were enrolled. A 1-year follow-up Kaplan-Meier survival analysis was used for evaluating the correlation between 5-MTP and major adverse cardiovascular event (MACE) while Cox proportional-hazards regression was used to identify predictive values of 5-MTP on MACE after AMI. RESULTS: Increased 5-MTP level led to a significant downtrend in the incidence of MACE (All Log-rank p < 0.05). Thus, a high baseline 5-MTP could reduce the 1-year incidence of MACE (HR = 0.33, 95%Cl 0.17-0.64, p = 0.001) and heart failure (HF) (HR = 0.28, 95% Cl 0.13-0.62, p = 0.002). Subgroup analysis indicated the predictive value of 5-MTP was more significant in patients aged ≤ 65 years and those with higher baseline NT-proBNP, T2DM, STEMI, and baseline HF with preserved LVEF (HFpEF) characteristics. CONCLUSIONS: Plasma 5-MTP is an independent and protective early biomarker for 1-year MACE and HF events in patients with AMI, especially in younger patients and those with T2DM, STEMI, and baseline HFpEF characteristics.

14.
Front Cell Infect Microbiol ; 13: 1068809, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36909732

RESUMO

Background: Multiple regimens have been widely used in the eradication treatment of Helicobacter pylori infection in children. However, there is a lack of comparison and evaluation of their effectiveness in different regions of the world. Methods: Randomized controlled trials were retrieved. Review Manager 5.4, Stata SE 15 and R 4.0.4 statistical software were used to analyze date. The ranking probability is assessed according to the surfaces under cumulative ranking (SUCRA). Results: 163 studies were eligible for this study, involving 336 arms and 18,257 children, and 10 different interventions. The results showed that the eradication rates of sequential therapy with probiotics (SP), bismuth-containing quadruple (Quadruple) therapy, concomitant therapy and PCN therapy were at least 90%. Cumulative ranking showed that SP therapy had the best eradication effect (SUCRA 92.7%) whereas Bismuth-containing triple therapy (B) had the worst (SUCRA 3.5%). Subgroup analysis suggested that SP therapy ranked first in China and other regions, and the ranking of Triple therapy with probiotics therapy (TP) was equally stable (SUCRA 72.0% vs 76.4% respectively). The security of the SP and TP therapy had great advantages. Conclusions: As for the eradication treatment of Helicobacter pylori infection in children, SP therapy ranks highest. SP and TP therapies are most safe.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Humanos , Criança , Bismuto/uso terapêutico , Antibacterianos/uso terapêutico , Metanálise em Rede , Quimioterapia Combinada , Resultado do Tratamento
15.
RSC Adv ; 13(5): 2811-2819, 2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36756418

RESUMO

Nanorod-supported (Pt-Pd)/CeO2 catalysts were synthesized by a simple method of dealloying Al91.7Ce8 Pt X Pd0.3-X (X = 0, 0.075, 0.1, 0.15, 0.2, 0.3) alloy ribbons. SEM and TEM characterization implied that after calcination treatment, the achieved resultants exhibited interspersed nanorod structures with a rich distribution of nanopores. Catalytic tests showed that the (Pt0.1-Pd0.2)/CeO2 catalyst calcined at 300 °C exhibited the highest catalyst activity for CO oxidation when compared with other catalysts prepared at different noble metal ratios or calcined at other temperatures, whose complete reaction temperature was as low as 100 °C. The outstanding catalytic performance is ascribed to the stable framework structure, rich gas pathways and collaborative effect between the noble Pt and Pd bimetals.

16.
ACS Omega ; 8(13): 11889-11896, 2023 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-37033829

RESUMO

The nanorod-structured (Au-Pd)/CeO2 catalysts with different Au/Pd ratios were prepared from Al-Ce-Au-Pd precursor alloys through combined dealloying and calcination treatment. XRD, SEM, TEM, XPS, Raman spectroscopy, and N2 adsorption-desorption measurements were applied to test the structure and physicochemical properties of samples. Catalytic evaluation results imply that the (Pd0.15-Au0.15)/CeO2 catalyst calcined at 500 °C possesses optimal catalytic activity for CO oxidation when compared with other catalysts with different Au/Pd ratios or (Pd0.15-Au0.15)/CeO2 calcined at other temperatures, whose 50% and 99% reaction temperature can be reached as low as 50 and 85 °C, respectively. This superior catalytic property is attributed to their robust nanorod structure and the introduction of noble bimetal Pd and Au, which can construct a nanoscale interface to access fast electron motion, thus enhancing catalytic efficiency.

17.
Ann Med ; 55(1): 2232369, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37453928

RESUMO

BACKGROUND: Bile acids play crucial roles in various metabolisms, as well as Lactobacillus in the intestine. But studies on their roles in acute coronary syndrome (ACS) are still insufficient. The aim of this study was to investigate their role and potential association with the severity of coronary lesions and the prognosis of ACS. METHODS: Three hundred and sixty ACS patients were selected. Detection of gut Lactobacillus levels was done through 16S rDNA sequence analysis. Evaluation of the extent of lesions was done using the SYNTAX (SS) score. Mediation analysis was used to assess the relationship between serum total bile acid (TBA), Lactobacillus, atherosclerotic lesions and prognosis of ACS. RESULTS: Logistic regressive analysis disclosed that serum TBA and Lactobacillus were independent predictors of coronary lesions (high vs. low SS: serum TBA adjusted odds ratio (aOR) = 0.8, 95% confidence interval (CI): 0.6-0.9, p < .01; Lactobacillus: aOR = 0.9, 95% CI: 0.9-1.0, p = .03). According to multivariate Cox regression analysis, they were negatively correlated with the overall risk of all-cause death (serum TBA: adjusted hazard ratio (aHR) = 0.1, 95% CI: 0.0-0.6, p = .02; Lactobacillus: aHR = 0.6, 95% CI: 0.4-0.9, p = .01), especially in acute myocardial infarction (AMI) but not in unstable angina pectoris (UAP). Ulteriorly, mediation analysis showed that serum TBA played an important role as a mediation effect in the following aspects: Lactobacillus (17.0%, p < .05) â†’ SS association (per 1 standard deviation (SD) increase), Lactobacillus (43.0%, p < .05) â†’ all-cause death (per 1 SD increase) and Lactobacillus (45.4%, p < .05) â†’ cardiac death (per 1 SD increase). CONCLUSIONS: The lower serum TBA and Lactobacillus level in ACS patients, especially in AMI, was independently linked to the risk of coronary lesions, all-cause death and cardiac death. In addition, according to our mediation model, serum TBA served as a partial intermediate in predicting coronary lesions and the risk of death by Lactobacillus, which is paramount to further exploring the mechanism of Lactobacillus and bile acids in ACS.KEY MESSAGESLower level of serum total bile acid (TBA) was highly associated with the severity of coronary lesions, myocardial damage, inflammation and gut Lactobacillus in acute coronary syndrome (ACS) patients, especially in acute myocardial infarction (AMI).Lower level of serum TBA was highly associated with mortality (including all-cause death and cardiac death) in patients with ACS, especially with AMI.Serum TBA had a partial mediating effect rather than regulating effect between gut Lactobacillus and coronary lesions and prognosis of ACS.


Assuntos
Síndrome Coronariana Aguda , Aterosclerose , Infarto do Miocárdio , Humanos , Ácidos e Sais Biliares , Prognóstico , Aterosclerose/complicações , Morte
18.
Foods ; 11(13)2022 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-35804786

RESUMO

In China, food has become safer over the past five years, especially commonly consumed foods. Food supervision sampling has played an important role in improving food safety. However, consumer acceptance of the results of food safety supervision have not kept pace. Communicating actual food safety risks to consumers and improving the public trust in food safety supervision sampling inspection has become an important issue. This study focused on food safety surveillance sampling of commonly consumed foods. In total, 4408 adult consumers were surveyed between August and October 2021. Structural equation modeling was performed for data analysis. This study found significant differences along gender lines and across different cities and levels of education with respect to evaluating competence trust and care trust on food supervision sampling inspection. This study identified the public's competence trust, care trust, and perception of food safety as factors that significantly affect one's attitude toward supervision sampling inspection. Care trust showed a more pronounced effect on trust enhancement than competence trust. The present study also provides some practical measures for food safety supervisors to improve public trust in the national food inspection. Specifically, the sampling process should be open and transparent.

19.
Phytomedicine ; 100: 154073, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35397285

RESUMO

BACKGROUND: The evolution of resistance to antimicrobials is a ubiquitous phenomenon. The evolution of antibiotic resistance in Staphylococcus aureus suggests that there is no remedy with sustaining effectiveness against this pathogen. The limited number of antibacterial drug classes and the common occurrence of cross-resistant bacteria reinforce the urgent need to discover new compounds targeting novel cellular functions. Natural products are a potential source of novel antibacterial agents. Anti-MRSA (methicillin-resistant S. aureus) bioactive compounds from Streptomyces and the anti-MRSA activity of a series of plant extracts have been reviewed respectively. However, there has been no detailed review of the precise bioactive components from plants. PURPOSE: The present review aimed to summarize the phytochemicals that have been reported with anti-MRSA activities, analyze their structure-activity relationship and novel anti-MRSA mechanisms. METHODS: Data contained in this review article are compiled from the authoritative databases PubMed, Web of Science, Google Scholar, and so on. RESULTS: This review summarizes 100 phytochemicals (27 flavonoids, 23 alkaloids, 17 terpenes and 33 others) that have been tested for their anti-MRSA activity. Among these phytochemicals, 39 compounds showed remarkable anti-MRSA activity with MIC values less than 10 µg/ml, 14 compounds with MIC ranges including values < 10 µg/ml, 5 compounds with MIC values less than 5 µM; 11 phytochemicals show synergism anti-MRSA effects in combination with antibiotics. Phytochemicals exerted anti-MRSA activities mainly by destroying the membrane structure and inhibiting the efflux pump. CONCLUSIONS: The 58 compounds with excellent anti-MRSA activity the 11 compounds with synergistic anti-MRSA effect, especially cannabinoids, xanthones and fatty acids should be further studied in vitro. Novel targets, such as cell membrane and efflux pump could be promising alternatives to develop antibacterial drugs in the future in order to prevent drug resistance.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Antibacterianos/farmacologia , Sinergismo Farmacológico , Humanos , Testes de Sensibilidade Microbiana , Compostos Fitoquímicos/farmacologia , Infecções Estafilocócicas/microbiologia
20.
Front Pharmacol ; 13: 870928, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36059973

RESUMO

Background: Necroptosis and inflammation are closely related to the pathogenesis of respiratory syncytial virus (RSV). Acteoside (AC), a natural phenylpropanoid glycoside from Kuding Tea, has significant anti-RSV effect. However, the roles of AC on RSV-induced lung necroptosis and inflammation are yet to be elucidated. Methods: The effects of AC were investigated in BALB/c mice and A549 cells. Lung histopathology was observed through H&E staining. The viral titer was assessed via plaque assay. The RSV-F expression was determined by RT-qPCR and immunohistochemistry assay. The levels of cytokines were detected by ELISA and RT-qPCR. The necroptosis rate and mitochondrial membrane potential were evaluated via flow cytometry. The expressions of HMGB1/NF-κB and RIP1/RIP3/MLKL/PGAM5/DRP1 were detected by western blot. Additionally, untargeted metabolomics was conducted to investigate the metabolic profiles and related metabolic pathways via Gas Chromatography-Mass Spectrometry. Results: The results showed that compared with the RSV-infected group, AC treatment significantly attenuated lung pathological damage, virus replication, and cytokines levels. AC also alleviated RSV-induced necroptosis and mitochondrial dysfunction in vitro and in vivo. Moreover, AC treatment down-regulated the expression of HMGB1, p-Iκbα/Iκbα, p-p65/p65, RIP1, RIP3, MLKL, PGAM5, and DRP1. Furthermore, metabolomic analyses suggested that the perturbations in major metabolites of AC therapy were related to variations in amino acid and energy metabolism. Conclusion: Our findings validated the beneficial effects of AC in suppressing necroptosis and regulating metabolism, suggesting AC may be a new drug candidate for RSV infection.

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