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1.
J Ethnopharmacol ; 330: 118224, 2024 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-38642623

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Sophorae tonkinensis Radix et Rhizoma (STR) is an extensively applied traditional Chinese medicine (TCM) in southwest China. However, its clinical application is relatively limited due to its hepatotoxicity effects. AIM OF THE STUDY: To understand the material foundation and liver injury mechanism of STR. MATERIALS AND METHODS: Chemical compositions in STR and its prototypes in mice were profiled by ultra-performance liquid chromatography coupled quadrupole-time of flight mass spectrometry (UPLC-Q/TOF MS). STR-induced liver injury (SILI) was comprehensively evaluated by STR-treated mice mode. The histopathologic and biochemical analyses were performed to evaluate liver injury levels. Subsequently, network pharmacology and multi-omics were used to analyze the potential mechanism of SILI in vivo. And the target genes were further verified by Western blot. RESULTS: A total of 152 compounds were identified or tentatively characterized in STR, including 29 alkaloids, 21 organic acids, 75 flavonoids, 1 quinone, and 26 other types. Among them, 19 components were presented in STR-medicated serum. The histopathologic and biochemical analysis revealed that hepatic injury occurred after 4 weeks of intragastric administration of STR. Network pharmacology analysis revealed that IL6, TNF, STAT3, etc. were the main core targets, and the bile secretion might play a key role in SILI. The metabolic pathways such as taurine and hypotaurine metabolism, purine metabolism, and vitamin B6 metabolism were identified in the STR exposed groups. Among them, taurine, hypotaurine, hypoxanthine, pyridoxal, and 4-pyridoxate were selected based on their high impact value and potential biological function in the process of liver injury post STR treatment. CONCLUSIONS: The mechanism and material foundation of SILI were revealed and profiled by a multi-omics strategy combined with network pharmacology and chemical profiling. Meanwhile, new insights were taken into understand the pathological mechanism of SILI.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Medicamentos de Ervas Chinesas , Rizoma , Animais , Doença Hepática Induzida por Substâncias e Drogas/patologia , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Camundongos , Masculino , Medicamentos de Ervas Chinesas/farmacologia , Sophora/química , Fígado/efeitos dos fármacos , Fígado/patologia , Fígado/metabolismo , Metabolômica , Cromatografia Líquida de Alta Pressão , Farmacologia em Rede , Multiômica , Animais não Endogâmicos
2.
Anal Chem ; 96(16): 6366-6372, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38598690

RESUMO

Sensitive detection of small molecules with biological and environmental interests is important for many applications, such as food safety, disease diagnosis, and environmental monitoring. Herein, we propose a highly selective antibody-bridged DNAzyme walker to sensitively detect small molecules. The antibody-bridged DNAzyme walker consists of a track, small-molecule-labeled DNAzyme walking strand, and antibody against small molecules. The track is built by co-modifying fluorophore-labeled substrates and small-molecule-labeled DNA linkers onto a gold nanoparticle (AuNP). In the absence of the target molecule, the antibody binds small molecule labels at the DNAzyme walking strand and the DNA linker, driving the DNAzyme walking strand on the surface of the AuNP. The attached DNAzyme walking strand moves along the track and cleaves substrates to generate high fluorescence signals to achieve signal amplification. As target molecules exist, they competitively bind with antibody to displace the small-molecule-labeled linker and DNAzyme walking strand, rendering the DNAzyme walker inactive in substrate cleavage and causing weak fluorescence. By using this antibody-bridged DNAzyme walker, we achieved sensitive detection of two biologically important small molecules, digoxin and folic acid. This work provides a new paradigm by combining the signal amplification strategy of a DNA walker and immunorecognition for sensitive and selective detection of small molecules.

3.
Nat Prod Res ; : 1-7, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38289060

RESUMO

Searching for new anti-ischemic stroke (anti-IS) drugs has always been a hot topic in the pharmaceutical industry. Natural products are an important source of discovering anti-IS drugs. The aim of the present study is to extract, rapidly prepare and explore the neuroprotective effect of texasin, a main active constituent from Caragana jubata (Pall.) Poir., which is a kind of Tibetan medicine with a clear anti-IS effect. The results showed that 95% ethanol was the optimal extraction solvent. A three-step rapid preparation method for texasin was successfully established, with a purity of 99.2%. Texasin at the concentration of 25-100 µM had no effect on the viability of normal cultured PC12 cells; 12.5 and 25 µM texasin could enhance the viability of PC12 cells damaged by oxygen and glucose deprivation/reoxygenation (OGD/R), and their effects are comparable to the positive drug edaravone at the concentration of 50 µM. Compared with the normal group, the expression of Bcl-2 protein in OGD/R-injured PC12 cells was downregulated (p < 0.01), and that of PERK, eIF2α, ATF4, CHOP, Bax and Cleaved caspase-3 proteins were upregulated (p < 0.01, p < 0.001). Compared with the OGD/R group, 25 µM texasin could upregulate the expression of Bcl-2 protein (p < 0.01), and downregulate that of PERK, eIF2α, ATF4, CHOP, Bax and Cleaved caspase-3 proteins (p < 0.01, p < 0.001). The 7-OH and 1-O of texasin formed H-bonds with residues Cys891 of the hinge ß-strand of PERK, which is crucial for kinase inhibitors. The above results suggest that the method established in the present study achieved rapid preparation of high-purity texasin. Texasin might inhibit neuronal apoptosis via the regulation of endoplasmic reticulum stress PERK/eIF2α/ATF4/CHOP signalling pathway to exert a protective effect on OGD/R-injured PC12 cells. Aiding by molecular docking, texasin was assumed to be a potential PERK inhibitor.

4.
Nano Lett ; 23(24): 11727-11733, 2023 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-38014963

RESUMO

We demonstrated optical bistability in an amorphous silicon Mie resonator with a size of ∼100 nm and Q-factor as low as ∼4 by utilizing photothermal and thermo-optical effects. We not only experimentally confirmed the steep intensity transition and the hysteresis in the scattering response from silicon nanocuboids but also established a physical model to numerically explain the underlying mechanism based on temperature-dependent competition between photothermal heating and heat dissipation. The transition between the bistable states offered particularly steep superlinearity of scattering intensity, reaching an effective nonlinearity order of ∼100th power over excitation intensity, leading to the potential of advanced optical switching devices and super-resolution microscopy.

5.
Nat Prod Res ; : 1-7, 2023 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-37661314

RESUMO

2,7,2'-Trihydroxy-3,4,4'7'-tetramethoxy-1,1'-biphenanthrene (1), a previously undescribed biphenanthrene, and five known phenanthrenes, i.e. 2,5-dihydroxy-4-methoxy-9,10-dihydroxyphenanthrene (2), 2,4-dihydroxy -7-methoxy-9,10-dihydroxyphenanthrene (3), 7-hydroxy-2-methoxy-phenanthrene-1,4-dione (4), 7-hydroxy-2-methoxy-9,10-dihydro-phenanthrene-1,4-dione (5), and 4,4',7,7'-tetrahydroxy-2,2'-dimethoxy-9,9',10,10'-tetrahydro-1,1'-biphenanthrene (6) were isolated from the whole plant (stems, leaves, roots and fruits) of Liparis nervosa (Thunb.) Lindl., which is a medicinal plant of the genus Liparis in the Orchidaceae family. The structures of isolates were identified using spectroscopic methods, including NMR and mass spectrometry. Additionally, the cytotoxic potency of all the isolates against human lung cancer A549 cell line was evaluated by an MTT assay. All the isolated compounds showed cytotoxic activities with IC50 values in the range of 10.20 ± 0.81 to 42.41 ± 2.34 µM. The obtained data highlight the importance of L. nervosa as a source of natural lead compounds for cancer therapy.

6.
J Colloid Interface Sci ; 652(Pt A): 23-33, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37591080

RESUMO

The oxygen evolution reaction (OER) is an important semi-reaction in the electrocatalytic water splitting for hydrogen energy production, and the development of efficient and low-cost electrocatalysts to solve the problem of slow 4-electron transport kinetics in the OER process is key. In this work, a pre-electrocatalyst with the heterogeneous interfacial structure, Prussian blue-modified nickel sulfide with sulfur vacancies (PB/NS-Sv), was designed and then converted to iron-nickel bilayer hydroxyl oxides in oxygen-rich vacancies (FeOOH/NiOOH-Ov@NS) through electrochemical oxidative reconstruction to obtain a truly stable and efficient active material. The study utilized in situ Raman to observe the transition from PB/NS-Sv to FeOOH/NiOOH-Ov@NS during the reaction. The electronic density of states in FeOOH/NiOOH-Ov@NS is regulated by the bilayer hydroxyl metal oxide synergistic effect and the abundant oxygen defect of Mental-OOH-Ov, which significantly improves OER catalytic performance. FeOOH/NiOOH-Ov@NS requires a low overpotential of only 257 mV in 1 mol/L KOH at 100 mA cm-2 current density, has a small Tafel slope of 35.2 mV dec-1 and has excellent stability for 150 h at 100 mA cm-2 current density, making it a promising candidate for industrial applications.

7.
J Colloid Interface Sci ; 646: 503-516, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37209550

RESUMO

Stress engineering can improve catalytic performance by straining the catalyst lattice. An electrocatalyst, Co3S4/Ni3S2-10%Mo@NC, was prepared with abundant lattice distortion to boost oxygen evolution reaction (OER). With the assistance of the intramolecular steric hindrance effect of metal-organic frameworks, slow dissolution by MoO42- of the Ni substrate and recrystallization of Ni2+ was observed in the process of Co(OH)F crystal growth with mild temperature and short time reaction. The lattice expansion and stacking faults created defects inside the Co3S4 crystal, improved the material conductivity, optimized the valence band electron distribution of the material, and promoted the rapid conversion of the reaction intermediates. The presence of reactive intermediates of the OER under catalytic conditions was investigated using operando Raman spectroscopy. The electrocatalysts exhibited super high performance, a current density of 10 mA cm-2 at an overpotential of 164 mV and 100 mA cm-2 at 223 mV, which were comparable to those of integrated RuO2. Our work for the first time demonstrates that the dissolution-recrystallization triggered by strain engineering is a good modulation approach to adjust the structure and surface activity of catalyst, suggesting promising industrial application.

8.
J Colloid Interface Sci ; 644: 358-367, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37120884

RESUMO

Inorganic-organic hybrids are promising anode catalysts to realize high activity and stability. Herein, an amorphous-dominated transition metal hydroxide-organic framework (MHOF) with isostructural mixed-linker was successfully synthesized on nickel foam (NF) substrate. The designed IML24-MHOF/NF exhibited remarkable electrocatalytic activity with an ultralow overpotential of 271 mV for oxygen evolution reaction (OER) and a potential of 1.29 V vs. reversible hydrogen electrode for urea oxidation reaction (UOR) at 10 mA·cm-2. Furthermore, the IML24-MHOF/NF||Pt-C cell required only 1.31 V for urea electrolysis at 10 mA·cm-2, which was much smaller than traditional water splitting (1.50 V). When coupled with UOR, the hydrogen yield rate was faster (1.04 mmol·h-1) than with OER (0.32 mmol·h-1) at 1.6 V. The structure characterizations, together with operando monitoring, including operando Raman, Fourier transform infrared, electrochemical impedance spectroscopy, and alcohol molecules probe, revealed that: (1) amorphous IML24-MHOF/NF prefers self-adaptive reconstruction into active intermediate species against the external stimulus; (2) pyridine-3,5-dicarboxylate-incorporation into parent framework reconfigures electronic structure of system, thus mediating the absorption of oxygen-containing reactants during anodic oxidation reactions, such as O* and COO*. This work provides a new approach for boosting the catalytic activity of anodic electro-oxidation reactions by trimming the structure of MHOF-based catalysts.

9.
J Colloid Interface Sci ; 640: 1-14, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-36827844

RESUMO

Metal-organic frameworks (MOFs) with conjugation carboxylate ligands as electrocatalysts can significantly improve oxygen evolution reaction (OER), but the role of π-interaction on the reactive sites of OER is often neglected. We intend to unravel the mechanism of how π-interaction enhances OER performance. The results of Rietveld refinement, density functional theory (DFT) calculations, and in-situ Raman spectra show that π-interaction can efficiently modulate the local spin configuration of metal centers, facilitate γ-Ni1-xFexOOH active species with high-valence Ni sites modified by high-spin Fe, accelerate electron transfer, optimize the d-band center together with the beneficial rate-determining step of OER. NiFe-BPDC MOFs/NF with 0.8559 eV π-interaction energy generated γ-Ni1-xFexOOH in only 60 s at 1.4 V, demonstrating that π-interaction promotes the rapid generation of highly active reactive sites. Furthermore, the results of in-situ Raman and electron paramagnetic resonance (EPR) spectra reveal that the deprotonation and deoxygenation steps of OER are accompanied by changes in the oxidation state of metal ions and the generation of oxygen vacancies on the surface of catalysts. In addition, NiFe-BPDC MOFs/NF rapidly completes the deprotonation and deoxygenation steps, and it requires only 288 mV overpotential to reach 100 mA/cm2 with 100 h of stability, suggesting promising industrial application.

10.
Bioresour Technol ; 361: 127710, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35905877

RESUMO

Due to the potential ecological risks of organic pollution in sediments, aquatic ecosystems are currently facing substantial environmental threats. Assessing and controlling sediment pollution has become a huge challenge. Therefore, this study proposes a novel strategy for predicting organic pollution indicators for sediment, as well as an effective resource-utilization method. Contaminated sediments were converted into catalysts for sulfate radical advanced oxidation technologies by a one-step calcination method. The results revealed that the catalyst excelled in activating peroxymonosulfate to degrade tetracycline via a non-radical pathway. Most importantly, a predictive model of organic pollution indicators was established by machine learning. This study provides a novel approach for resource utilization and a strategy for assessing organic pollution in sediments.


Assuntos
Sedimentos Geológicos , Poluentes Químicos da Água , Ecossistema , Monitoramento Ambiental , Poluição Ambiental , Aprendizado de Máquina , Poluentes Químicos da Água/análise
11.
Front Pharmacol ; 13: 794277, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35355711

RESUMO

Zanthoxylum nitidum (Roxb.) DC. (ZN), with strong effects of anti-inflammation and antioxidant activities is treated as a core herb in traditional Chinese medicine (TCM) preparation for treating stomachache, toothache, and rheumatoid arthritis. However, the active ingredients of ZN are not fully clarified due to its chemical complexity. In the present study, a double spectrum-effect analysis strategy was developed and applied to explore the bioactive components in herbs, and ZN was used as an example. Here, the chemical components in ZN were rapidly and comprehensively profiled based on the mass defect filtering-based structure classification (MDFSC) and diagnostic fragment-ion-based extension approaches. Furthermore, the fingerprints of 20 batches of ZN samples were analyzed by high-performance liquid chromatography, and the anti-inflammatory and antioxidant activities of the 20 batches of ZN samples were studied. Finally, the partial least squares regression (PLSR), gray relational analysis models, and Spearman's rank correlation coefficient (SRCC) were applied to discover the bioactive compounds in ZN. As a result, a total of 48 compounds were identified or tentatively characterized in ZN, including 35 alkaloids, seven coumarins, three phenolic acids, two flavonoids, and one lignan. The results achieved by three prediction models indicated that peaks 4, 12, and 17 were the potential anti-inflammatory compounds in ZN, whereas peaks 3, 5, 7, 12, and 13 were involved in the antioxidant activity. Among them, peaks 4, 5, 7, and 12 were identified as nitidine, chelerythrine, hesperidin, and oxynitidine by comparison with the standards and other references. The data in the current study achieved by double spectrum-effect analysis strategy had great importance to improve the quality standardization of ZN, and the method might be an efficiency tool for the discovery of active components in a complex system, such as TCMs.

12.
Nanoscale ; 14(4): 1370-1379, 2022 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-35018403

RESUMO

Lattice distortion is an important way to improve the electrocatalytic performance and stability of two-dimensional transition metal materials (2d-TMSs). Herein, a lattice distortion nickel-molybdenum sulfide electrocatalyst on foam nickel (NiMoS4-12/NF) has been synthesized through a novel, simple, and effective crystalline-amorphous strategy. The electrocatalyst only requires 1.47 V to obtain 10 mA cm-2 for overall water splitting (OWS) and can function stably for 100 h at a current density of 100 mA cm-2, demonstrating an excellent electrocatalytic performance and stability. From the results of the transmission electron microscopy (TEM) and electron paramagnetic resonance spectroscopy (EPR), it can be seen that the (104) crystal lattice of NiMoS4-12 undergoes interface strain under the crystalline-amorphous state, resulting in rich sulfur defects caused by lattice distortion, which could improve the intrinsic catalytic activity of NiMoS4-12. According to the differential charge density analysis, around the sulfur defects, the Mo and Ni atoms with abundant lone pairs of electrons acted as libraries of lone pairs of electrons to enable an efficient hydrogen evolution reaction (HER). From the total density of states (TDOS) and the Gibbs free energy of hydrogen adsorption (ΔGH*), the libraries of lone pairs of electrons not only effectively optimized the distribution of the surface electron density of states at the Fermi level, but also reduced the ΔGH*, thereby improving the intrinsic HER electrocatalytic performance. The in situ Raman test results demonstrate that during the oxygen evolution reaction (OER), the surface of the nickel molybdenum sulfide was reconstructed, and highly active Ni-OOH was generated. From the calculated free energy diagrams, the Ni-OOH could optimize the reaction barrier of the rate-determining step (RDS) for the OER to enhance the slow oxygen evolution reaction kinetics. This work will contribute to the rational design of a 2d-TMSs electrocatalyst, as well as investigation of the catalytic mechanism.

13.
Phytomedicine ; 96: 153911, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35026505

RESUMO

BACKGROUND: Yindan Xinnaotong soft capsule (YDXNT) is a clinically effective herbal prescription used for the treatment of cardiovascular and cerebrovascular diseases. Since Chinese medicines (CMs) exert their effects via a "multiple-components and multiple-targets" mode, discovery of the active compounds with interactive effects may contribute to reveal their mechanisms of action. PURPOSE: This study aimed to establish an image-based fingerprint-efficacy screening strategy to identify active compounds with interaction effects from CM prescription, using YDXNT to inhibit microglia-mediated neuroinflammation as an instance. METHODS: A multi-component random content-oriented chemical library of YDXNT was constructed by uniform design, and their chemical fingerprint was profiled by liquid chromatography-mass spectrometry (LC-MS) and gas chromatography-mass spectrometry (GC-MS) methods. Then the neuroinflammation activities of chemical library members of YDXNT were determined by image-based dual phenotypic quantification. Subsequently, fingerprint-efficacy correlation and random forest analysis were applied to predict the potentially active compounds with interactive effects. Finally, the interactive effects among the active compounds were confirmed by quantitative polymerase chain reaction (qPCR) and apoptosis analysis, and network pharmacology was applied to explore the possible mechanisms. RESULTS: Image-based fingerprint-efficacy correlation analysis revealed that six tanshinones (TNs) and four flavonoids (FAs) were potential anti-neuroinflammatory compounds. The inter-family of TNs and FAs possessed obvious interactive effects (combination index ≤ 0.825). Moreover, the combination of scutellarein and tanshinone I (2:1, w/w) was discovered as the possible interactive combinatorial components, which, comparing with individual scutellarein or tanshinone I, shown more powerful effects on anti-inflammatory and anti-apoptotic effects in lipopolysaccharide (LPS)-induced BV2 cells. Network pharmacology showed that the active compounds might suppress microglia-mediated neuroinflammation via multiple targets in the T cell receptor, Jak-STAT, and Toll-like receptor signaling pathways. CONCLUSION: The image-based fingerprint-efficacy strategy simplifies the screening process of efficacious component combinations in CMs for complex diseases, which also offers a promising approach to explore the integrative therapeutic mechanisms of CMs.


Assuntos
Medicamentos de Ervas Chinesas , Anti-Inflamatórios , Cromatografia Líquida , Medicamentos de Ervas Chinesas/farmacologia , Humanos , Farmacologia em Rede , Doenças Neuroinflamatórias
14.
J Pharm Biomed Anal ; 202: 114140, 2021 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-34015592

RESUMO

A rapid ultra-high performance liquid chromatography coupled with triple quadrupole tandem mass spectrometry (UHPLC-QqQ MS/MS) approach with high sensitivity and selectivity was developed for the quantification of twenty compounds, including 9 saponins, 8 flavonoids, 2 oligosaccharide esters and 1 phenolic acid, in rat plasma and brain, which was administrated intragastrically with Jia-Wei-Qi-Fu-Yin (JWQFY), Mass spectrometric detection was operated under multiple reaction monitoring (MRM) mode. All calibration curves possessed good linearity with correlation coefficients ( r2) higher than 0.9916 in their respective linear ranges. For intra- and inter-day precision, all the relative standard deviations (RSDs) at different levels were less than 14.68 %. Based on the UHPLC-QqQ MS/MS quantitative results, pharmacokinetic study and brain distribution of multiple components in JWQFY was then successfully performed. As a result, constituents with discrepancy structures showed diverse pharmacokinetic and distribution characteristics. For instance, ferulic acid (phenolic acid), 3, 6'-disinapoyl sucrose and tenuifoliside A (oligosaccharide esters) showed short Tmax (< 10 min), whereas the Tmax of ginsenosides Rb1, Rb2 and Rc (ppd-type terpenoid saponins) were much longer (> 4 h). Besides, ferulic acid, epimedin C, icariin, glycyrrhizin, ginsenoside Rb1 and ginsenoside Rg1 were considered as the potential effective ingredients of JWQFY because of their relatively high exposure to blood and brain. Our study would provide relevant information for discovery of pharmacodynamic ingredients, as well as further action mechanisms investigations of JWQFY.


Assuntos
Medicamentos de Ervas Chinesas , Espectrometria de Massas em Tandem , Administração Oral , Animais , Encéfalo , Cromatografia Líquida de Alta Pressão , Ratos , Reprodutibilidade dos Testes
15.
Artigo em Inglês | MEDLINE | ID: mdl-33029181

RESUMO

The present study aims to investigate the roles of herb pairs containing Angelicae Sinensis Radix (Danggui) in Xin-Sheng-Hua Granule (XSHG) on hemolytic and aplastic anemia (HAA) mice. HAA model mice were induced by acetyl phenylhydrazine and cyclophosphamide; then the samples of XSHG and its decomposed recipes (DY, DC, DT, DH, DJ, and DZ) were orally administrated to these mice. Indicators of peripheral blood routine, organ index, and ATPase activities were tested. Moreover, the main effective components in these samples were also analyzed by UHPLC-TQ-MS/MS. Clear separation between the control and model groups from score plot of principal component analysis (PCA) was easily seen, indicating that HAA model was successfully conducted. Afterwards, relative distance calculation method between dose groups and control group from PCA score plot was adopted to evaluate the integrated effects of hematinic function of different samples. And the orders of hematinic effects were as follows: XHSG > DJ > DT > DZ > DH > DC > DY. Further analysis of these samples by UHPLC-TQ-MS/MS revealed that XSHG underwent complicated changes when herb pairs containing Danggui were excluded from XSHG, respectively. Compared with XSHG, the vast majority of active compounds in sample DY (formula minus herb pair Danggui-Yimucao) decreased significantly, which could partly explain why herb pair Danggui-Yimucao made great contribution to XSHG. These findings showed that withdrawal analysis method is a valuable tool to analyze the impacts of herb pairs containing Danggui on XSHG, which could lay foundation to reveal the compatibility rules of this formula.

17.
Nat Commun ; 11(1): 4101, 2020 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-32796839

RESUMO

Silicon photonics have attracted significant interest because of their potential in integrated photonics components and all-dielectric meta-optics elements. One major challenge is to achieve active control via strong photon-photon interactions, i.e. optical nonlinearity, which is intrinsically weak in silicon. To boost the nonlinear response, practical applications rely on resonant structures such as microring resonators or photonic crystals. Nevertheless, their typical footprints are larger than 10 µm. Here, we show that 100 nm silicon nano-resonators exhibit a giant photothermal nonlinearity, yielding 90% reversible and repeatable modulation from linear scattering response at low excitation intensities. The equivalent nonlinear index is five-orders larger compared with bulk, based on Mie resonance enhanced absorption and high-efficiency heating in thermally isolated nanostructures. Furthermore, the nanoscale thermal relaxation time reaches nanosecond. This large and fast nonlinearity leads to potential applications for GHz all-optical control at the nanoscale and super-resolution imaging of silicon.

18.
J Pharm Biomed Anal ; 189: 113467, 2020 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-32683191

RESUMO

Jia-Wei-Qi-Fu-Yin (JWQFY) is a newly developed anti-Alzheimer's disease (AD) prescription modified from a classical traditional Chinese medicine formula, Qi-Fu-Yin (QFY). However, a systematic understanding of its chemical constituents and molecular mechanisms is still elusive. To address this problem, comprehensive chemical profiling followed by network pharmacology-based analysis of JWQFY was performed. Firstly, a total of 136 compounds were characterized by high performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry (HPLC-QTOF MS), 17 of them were specifically identified in JWQFY comparing with QFY. Seventy compounds were further quantified via a validated HPLC coupled with triple quadrupole tandem mass spectrometry (QQQ MS) method. Then the protein targets of the seventy compounds were gathered from public databases for network construction. As a result, fifty-seven compounds were filtered, which interacted with 655 targets. Thirty-four of them were mapped into the KEGG pathway of AD, indicating JWQFY might exert anti-AD effects by anti-inflammation, neuronal apoptosis intervening, Aß production inhibition and phosphorylating tau protein moderating. Furthermore, in the compound-target-AD network, a list of hub compounds and hub targets was identified based on their topological features, including the degree, node betweenness and closeness. Four of the hub compounds were specifically originated from JWQFY, supporting the modification rationality of this formula. This study provided a scientific basis for understanding the bioactive compounds and the multi-target mechanism of JWQFY.


Assuntos
Doença de Alzheimer , Medicamentos de Ervas Chinesas , Doença de Alzheimer/tratamento farmacológico , Cromatografia Líquida de Alta Pressão , Humanos , Espectrometria de Massas em Tandem
19.
J Pharm Biomed Anal ; 174: 376-385, 2019 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-31202880

RESUMO

Alkaloids, the principal constituents in the caulis of Sinomenium acutum, have gained an increasing interest over the past decades since they are widely employed as a clinical treatment for rheumatoid arthritis. In the present study, an integrated characterization strategy by combining mass defect filtering-based structure classification (MDFSC) and diagnostic fragment-ion-based extension (DFIBE) was firstly proposed for rapid profiling of alkaloids in Sinomenii Caulis (SC) via ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry (UPLC-QTOF/MS). The rectangular MDFSC window could more accurately screen the target alkaloids of different types, and the DFIBE could facilitate the acquisition of characteristic fragment ions for structural elucidation of alkaloids. High-performance liquid chromatography (HPLC) fingerprints with principal component analysis (PCA) and hierarchical clustering analysis (HCA) was established for identifying the chemical markers and simultaneous determination of sinomenine, magnoflorine, menisperine, stepharanine and ehydrodiscretine. A total of 91 alkaloids, including 82 targeted ones (26 morphinans, 22 aporphines, 20 protoberberines and 14 benzylisoquinolines) were unambiguously identified or tentatively characterized in SC, and 14 of them were reported for the first time. Sinomenine and magnoflorine could be selected as chemical markers to evaluate the quality of SC from different localities. In conclusion, the proposed method provided a potential approach for chemical profiling and holistic quality control of herbal medicines.


Assuntos
Alcaloides/análise , Sinomenium/química , Aporfinas/análise , Artrite Reumatoide/tratamento farmacológico , Cromatografia Líquida de Alta Pressão , Análise por Conglomerados , Medicamentos de Ervas Chinesas/química , Humanos , Inflamação , Limite de Detecção , Espectrometria de Massas , Modelos Teóricos , Plantas Medicinais/química , Análise de Componente Principal , Controle de Qualidade
20.
J Chromatogr A ; 1601: 288-299, 2019 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-31138441

RESUMO

Discovering effective combinational components (ECCs) and quality control markers of TCMs is still facing challenges because the holistic healing system comprises hundreds of compounds. Here, taking Yindan Xinnaotong soft capsule (YDXNT), a TCMs preparation composed by 8 herbs, as a case, a strategy that integrated multiple chromatographic analysis and bioactivity assay was proposed for potential ECCs of neuroprotection discovery. Firstly, ultra-high performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry (UHPLC-QTOF MS) and gas chromatography-mass spectrometry (GC-MS) were applied for comprehensive profiling of the chemical constituents in YDXNT. Given the fact that the complex matrix interference makes it more difficult to identify potentially active compounds, we proposed a structure-diagnostic ions-oriented strategy to remove interference ions from the raw UHPLC-MS data. The proposed strategy consisted of different filtering methods, including diagnostic fragment ions filtering (DFIF), mass defect filtering (MDF) and neutral loss (NL). Using this strategy, a total of 124 compounds were rapidly identified. Among them, 62 non-volatile and 5 volatile constituents in 30 batches of YDXNT were quantified by UHPLC tandem triple quadrupole mass spectrometry (QQQ-MS) and GC-MS methods, respectively. In order to facilitate the quality control of YDXNT, candidate ECCs were selected based on the threshold setting of absolute -contents, and their neuroprotective effects were examined. Finally, a combination of 16 compounds, accounts for 2.80% (w/w) of original YDXNT, was identified as its potential ECCs, which could be considered for the improvement of quality standardization of YDXNT.


Assuntos
Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/farmacologia , Animais , Linhagem Celular , Células/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Células PC12 , Controle de Qualidade , Ratos , Espectrometria de Massas em Tandem
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