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1.
Plant Physiol ; 191(2): 1272-1287, 2023 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-36437699

RESUMO

Increasing planting density is one of the most effective ways to improve crop yield. However, one major factor that limits crop planting density is the weakened immunity of plants to pathogens and insects caused by dim light (DL) under shade conditions. The molecular mechanism underlying how DL compromises plant immunity remains unclear. Here, we report that DL reduces rice (Oryza sativa) resistance against brown planthopper (BPH; Nilaparvata lugens) by elevating ethylene (ET) biosynthesis and signaling in a Phytochrome B (OsPHYB)-dependent manner. The DL-reduced BPH resistance is relieved in osphyB mutants, but aggravated in OsPHYB overexpressing plants. Further, we found that DL reduces the nuclear accumulation of OsphyB, thus alleviating Phytochrome Interacting Factor Like14 (OsPIL14) degradation, consequently leading to the up-regulation of 1-Aminocyclopropane-1-Carboxylate Oxidase1 (OsACO1) and an increase in ET levels. In addition, we found that nuclear OsphyB stabilizes Ethylene Insensitive Like2 (OsEIL2) by competitively interacting with EIN3 Binding F-Box Protein (OsEBF1) to enhance ET signaling in rice, which contrasts with previous findings that phyB blocks ET signaling by facilitating Ethylene Insensitive3 (EIN3) degradation in other plant species. Thus, enhanced ET biosynthesis and signaling reduces BPH resistance under DL conditions. Our findings provide insights into the molecular mechanism of the light-regulated ET pathway and host-insect interactions and potential strategies for sustainable insect management.


Assuntos
Etilenos , Hemípteros , Oryza , Fitocromo B , Animais , Etilenos/metabolismo , Hemípteros/metabolismo , Oryza/metabolismo , Fitocromo B/genética , Fitocromo B/metabolismo
2.
J Sci Food Agric ; 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38501369

RESUMO

BACKGROUND: Fried foods are favored for their unique crispiness, golden color and flavor, but they also face great challenge because of their high oil content, high calories and the existence of compounds such as acrylamide and polycyclic aromatic hydrocarbons. Long-term consumption of fried foods may adversely affect health. Therefore, it is necessary to explore fried foods with lower oil contents and a high quality to meet the demand. RESULTS: A method of enzyme treatment was explored to investigate the effects of maltogenic amylase (MA), transglutaminase (TG) and bromelain (BRO) on the physicochemical properties of the batter and the quality of fried spring roll wrapper (FSRW). The results showed that the MA-, TG- or BRO-treated batters had a significant shear-thinning behavior, especially with an increase in viscosity upon increasing TG contents. FSRW enhanced its fracturability from 419.19 g (Control) to 616.50 g (MA-6 U g-1), 623.49 g (TG-0.75 U g-1) and 644.96 g (BRO-10 U g-1). Meanwhile, in comparison with BRO and MA, TG-0.5 U g-1 endowed batter with the highest density and thermal stability. MA-15 U g-1 and TG-0.5 U g-1 displayed FSRW with uniform and dense pores, and significantly reduced its oil content by 18.05% and 25.02%, respectively. Moreover, compared to MA and TG, BRO-50 U g-1 improved the flavor of FSRW. CONCLUSION: MA, TG or BRO played a key role in affecting the physicochemical properties of the batter and the quality of FSRW. TG-0.5 U g-1 remarkly reduced the oil content of FSRW with a great potential in practical application. © 2024 Society of Chemical Industry.

3.
J Org Chem ; 88(17): 12658-12667, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37595016

RESUMO

A photocatalytic synthesis of difluoromethylated selenides from selenosulfonates is described here. Bench-stable difluoromethyl phosphonium salt [Ph3PCF2H]Br reacts smoothly with selenosulfonates to give a series of functionalized difluoromethylated selenides in moderate to good yields via a radical process. This protocol is free of a stoichiometric base and reductant, has tolerance of functional groups, and has successful late-stage modification of bioactive molecules, which provides facile access to molecules of pharmaceutical relevance.

4.
World J Surg ; 47(5): 1153-1162, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36745198

RESUMO

BACKGROUND: Facilitating the recurrence of spontaneous voiding is considered to be a way to prevent urinary retention after surgery, which is of great importance in cholecystectomy. This study aimed to assess the effect of transcutaneous electrical acupoint stimulation (TEAS) on spontaneous voiding recovery after laparoscopic cholecystectom. METHODS: Participants who underwent elective laparoscopic cholecystectomy were randomly assigned to either the TEAS group or the sham group. Active TEAS or sham TEAS at specific acupuncture points was conducted intraoperatively and postoperatively. The primary outcome was the recovery speed of spontaneous voiding ability after surgery and secondary outcomes included postoperative urinary retention (POUR), voiding dysfunction, pain, anxiety and depression, and early recovery after surgery. RESULTS: A total of 1,948 participants were recruited and randomized to TEAS (n = 975) or sham (n = 973) between August 2018 and June 2020. TEAS shortens the time delay of the first spontaneous voiding after laparoscopic cholecystectomy (5.6 h [IQR, 3.7-8.1 h] in the TEAS group vs 7.0 h [IQR, 4.7-9.7 h] in the sham group) (p < 0.001). The TEAS group experienced less POUR (p = 0.020), less voiding difficulty (p < 0.001), less anxiety and depression (p < 0.001), reduced pain (p = 0.007), and earlier ambulation (p = 0.01) than the sham group. CONCLUSIONS: Our results showed that TEAS is an effective approach to accelerate the recovery of spontaneous voiding and reduce POUR which facilitates recovery for patients after laparoscopic cholecystectomy.


Assuntos
Colecistectomia Laparoscópica , Estimulação Elétrica Nervosa Transcutânea , Retenção Urinária , Humanos , Colecistectomia Laparoscópica/efeitos adversos , Estimulação Elétrica Nervosa Transcutânea/métodos , Retenção Urinária/etiologia , Retenção Urinária/terapia , Pontos de Acupuntura , Complicações Pós-Operatórias , Dor
5.
J Chem Phys ; 158(4): 044122, 2023 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-36725492

RESUMO

The nonadiabatic phenomena, which are characterized by a strong coupling between electronic and nuclear motions, are ubiquitous. The nonadiabatic effect of the studied system can be significantly affected by the surrounding environment, such as solvents, in which such nonadiabatic process takes place. It is essential to develop the theoretical models to simulate these processes while accurately modeling the solvent environment. The time-dependent density functional theory (TDDFT) is currently the most efficient approach to describe the electronic structures and dynamics of complex systems, while the polarizable continuum model (PCM) represents one of the most successful examples among continuum solvation models. Here, we formulate the first-order derivative couplings (DCs) between the ground and excited states as well as between two excited states by utilizing time-independent equation of motion formalism within the framework of both linear response and spin flip formulations of TDDFT/CPCM (the conductor-like PCM), and implement the analytical DCs into the Q-CHEM electronic structure software package. The analytic implementation is validated by the comparison of the analytical and finite-difference results, and reproducing geometric phase effect in the protonated formaldimine test case. Taking 4-(N,N-dimethylamino)benzonitrile and uracil in the gas phase and solution as an example, we demonstrate that the solvent effect is essential not only for the excitation energies of the low-lying excited-states but also for the DCs between these states. Finally, we calculate the internal conversion rate of benzophenone in a solvent with DC being used. The current implementation of analytical DCs together with the existing analytical gradient and Hessian of TDDFT/PCM excited states allows one to study the nonadiabatic effects of relatively large systems in solutions with low computational cost.

6.
J Phys Chem A ; 126(2): 239-248, 2022 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-34989581

RESUMO

Assessing and improving the performance of organic light-emitting diode (OLED) materials require quantitative prediction of rate coefficients for the intersystem crossing (ISC) and reverse ISC (RISC) processes, which are determined not only by the energy gap and the direct spin-orbit coupling (SOC) between the first singlet and triplet excited-states at a thermal equilibrium position of the initial electronic state but also by the non-Condon effects such as the Herzberg-Teller-like vibronic coupling (HTVC) and the spin-vibronic coupling (SVC). Here we apply the time-dependent correlation function approaches to quantitatively calculate the vibrationally resolved absorption and fluorescence spectra and ISC/RISC rates of a newly synthesized multiple-resonance-type (MR-type) thermally activated delayed fluorescence (TADF) emitter, 7-phenylquinolino[3,2,1-de]acridine-5,9-dione (7-PhQAD), with the inclusion of the Franck-Condon (FC), HTVC, and Duschinsky rotation (DR) effects. The SVC effect on the rates has also been approximately evaluated. We find that the experimentally measured ISC rates of 7-PhQAD originate predominantly from the vibronic coupling, consistent with the previous reports on other MR-type TADF emitters. The SVC effect on ISC rates is about 10 times larger than the HTVC effect, and the latter increases the ISC rates by more than 1 order of magnitude while it slightly affects the vibrationally resolved absorption and fluorescence spectra. The discrepancy between the theoretical and experimental results is attributed to inaccurately describing excited-states calculated by the time-dependent density functional theory as well as to not fully accounting for the complex experimental conditions. This work provides a demonstration of what proportion of ISC and RISC rate coefficients of a MR-type TADF emitter can be covered by the HTVC effect, and it opens design routes that go beyond the FC approximation for the future development of high-performance OLED devices.

7.
J Chem Phys ; 156(21): 210901, 2022 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-35676148

RESUMO

Time-dependent density functional theory (TDDFT) based approaches have been developed in recent years to model the excited-state properties and transition processes of the molecules in the gas-phase and in a condensed medium, such as in a solution and protein microenvironment or near semiconductor and metal surfaces. In the latter case, usually, classical embedding models have been adopted to account for the molecular environmental effects, leading to the multi-scale approaches of TDDFT/polarizable continuum model (PCM) and TDDFT/molecular mechanics (MM), where a molecular system of interest is designated as the quantum mechanical region and treated with TDDFT, while the environment is usually described using either a PCM or (non-polarizable or polarizable) MM force fields. In this Perspective, we briefly review these TDDFT-related multi-scale models with a specific emphasis on the implementation of analytical energy derivatives, such as the energy gradient and Hessian, the nonadiabatic coupling, the spin-orbit coupling, and the transition dipole moment as well as their nuclear derivatives for various radiative and radiativeless transition processes among electronic states. Three variations of the TDDFT method, the Tamm-Dancoff approximation to TDDFT, spin-flip DFT, and spin-adiabatic TDDFT, are discussed. Moreover, using a model system (pyridine-Ag20 complex), we emphasize that caution is needed to properly account for system-environment interactions within the TDDFT/MM models. Specifically, one should appropriately damp the electrostatic embedding potential from MM atoms and carefully tune the van der Waals interaction potential between the system and the environment. We also highlight the lack of proper treatment of charge transfer between the quantum mechanics and MM regions as well as the need for accelerated TDDFT modelings and interpretability, which calls for new method developments.


Assuntos
Simulação de Dinâmica Molecular , Teoria Quântica , Teoria da Densidade Funcional
8.
J Chem Phys ; 157(16): 164110, 2022 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-36319412

RESUMO

This work is devoted to deriving and implementing analytic second- and third-order energy derivatives with respect to the nuclear coordinates and external electric field within the framework of the hybrid quantum mechanics/molecular mechanics method with induced charges and dipoles (QM/DIM). Using these analytic energy derivatives, one can efficiently compute the harmonic vibrational frequencies, infrared (IR) and Raman scattering (RS) spectra of the molecule in the proximity of noble metal clusters/nanoparticles. The validity and accuracy of these analytic implementations are demonstrated by the comparison of results obtained by the finite-difference method and the analytic approaches and by the full QM and QM/DIM calculations. The complexes formed by pyridine and two sizes of gold clusters (Au18 and Au32) at varying intersystem distances of 3, 4, and 5 Å are used as the test systems, and Raman spectra of 4,4'-bipyridine in the proximity of Au2057 and Ag2057 metal nanoparticles (MNP) are calculated by the QM/DIM method and compared with experimental results as well. We find that the QM/DIM model can well reproduce the IR spectra obtained from full QM calculations for all the configurations, while although it properly enhances some of the vibrational modes, it artificially overestimates RS spectral intensities of several modes for the systems with very short intersystem distance. We show that this could be improved, however, by incorporating the hyperpolarizability of the gold metal cluster in the evaluation of RS intensities. Additionally, we address the potential impact of charge migration between the adsorbate and MNPs.

9.
J Chem Phys ; 156(12): 124104, 2022 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-35364897

RESUMO

Following the formulation of cavity quantum-electrodynamical time-dependent density functional theory (cQED-TDDFT) models [Flick et al., ACS Photonics 6, 2757-2778 (2019) and Yang et al., J. Chem. Phys. 155, 064107 (2021)], here, we report the derivation and implementation of the analytic energy gradient for polaritonic states of a single photochrome within the cQED-TDDFT models. Such gradient evaluation is also applicable to a complex of explicitly specified photochromes or, with proper scaling, a set of parallel-oriented, identical-geometry, and non-interacting molecules in the microcavity.

10.
Hereditas ; 159(1): 44, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36451177

RESUMO

BACKGROUND: Nonalcoholic Fatty Liver Disease (NAFLD) is a chronic Liver Disease prevalent all over the world. It has become more and more common in Japan, China and most western developed countries. The global prevalence rate is 25.24%, and the trend is increasing year by year. Related studies have shown that Cynarine has certain liver protection, lipid lowering and immune intervention effects. So, this study to systematically predict and analyze the mechanism of Cynarine in the treatment of non-alcoholic fatty liver disease (NAFLD) based on the integration of network pharmacology, molecular docking, and cell experiment. METHODS: We performed Heatmap and Venn diagram analyses to identify genes and targets in Cynarine treat NAFLD. The network of Cynarine-therapeutic targets and the protein-protein interaction network (PPI) was constructed. We used gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses to visualize associated functional pathways. The Sybyl tool was used to dock the Cynarine with key therapeutic targets molecularly. Finally, cell experiments were applied to validate the role of Cynarine in the treatment of NAFLD. RESULTS: The Cynarine could act on 48 targets of NAFLD, and the role of CASP3, TP53, MMP9, ELANE, NOTCH1 were more important. The PPI network showed that immune and inflammation-related targets played a pivotal role. The KEGG analysis found that the PI3K-Akt signaling pathway, cell cycle and MAPK signaling pathway may be the main pathways for Cynarine to prevent and treat NAFLD. Molecular docking studies confirmed that Cynarine has good binding activity with therapeutic targets. Cynarine reduced the fat deposition ability of NAFLD model cells, and effectively reduced the levels of ALT and AST released by liver cells due to excessive lipid accumulation. We also found that Cynarine inhibited the expression of AKT1 and MAPK1. CONCLUSIONS: This study revealed that Cynarine could significantly reduce the fat deposition ability of NAFLD model cells, which may be closely related to the effective regulation of AKT1 and MAPK1 expression by Cynarine.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Humanos , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/genética , Simulação de Acoplamento Molecular , Farmacologia em Rede , Fosfatidilinositol 3-Quinases , Lipídeos
11.
Molecules ; 27(17)2022 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-36080154

RESUMO

Radix Asteris (RA), also known as 'Zi Wan', is the dried root and rhizome of Aster tataricus L. f., which has been used to treat cough and asthma in many countries such as China, Japan, Korea and Vietnam. This article summarizes the available information on RA in ancient Chinese medicine books and modern research literature: its botanical properties, traditional uses, chemical composition, pharmacological activity, toxicity and quality control. Studies have shown that RA extracts contain terpenes, triterpenoid saponins, organic acids, peptides and flavonoids, and have various pharmacological activities such as anti-inflammatory, anti-tumor, anti-oxidation, and anti-depression. RA is considered to be a promising medicinal plant based on its traditional use, chemical constituents and pharmacological activities. However, there are few studies on its toxicity and the consistency of its components, which indicates the need for further in-depth studies on the toxicity and quality control of RA and its extracts.


Assuntos
Aster , Medicamentos de Ervas Chinesas , Plantas Medicinais , Anti-Inflamatórios , Medicamentos de Ervas Chinesas/química , Etnofarmacologia , Medicina Tradicional Chinesa , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/uso terapêutico , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico
12.
Molecules ; 27(24)2022 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-36558095

RESUMO

This study investigated the optimization of ultrasonic-assisted aqueous two-phase synchronous extraction of carbohydrates and polyphenols present in artichoke bud, evaluated their antioxidant activities in vitro, and analyzed the composition of carbohydrates and polyphenols by high-performance liquid chromatography (HPLC). The powder mass, ultrasonic time, ammonium sulfate concentration, and alcohol-water ratio were considered the influencing factors based on the single-factor experiment results, and a dual-response surface model was designed to optimize the synchronous extraction process to extract carbohydrates and polyphenols. The antioxidant activity was evaluated by measuring the scavenging capacity of ABTS+· and DPPH· and the reducing capacity of Fe3+. The optimal process conditions in this study were as follows: the powder mass of 1.4 g, ammonium sulfate concentration of 0.34 g/mL, alcohol-water ratio of 0.4, and ultrasonic time of 43 min. The polyphenol content in artichoke bud was 5.32 ± 0.13 mg/g, and the polysaccharide content was 74.78 ± 0.11 mg/g. An experiment on in vitro antioxidant activity showed that both carbohydrates and polyphenols had strong antioxidant activities, and the antioxidant activity of polyphenols was stronger than that of carbohydrates. The HPLC analysis revealed that the carbohydrates in artichoke bud were mannose, rhamnose, glucuronic acid, galacturonic acid, glucose, galactose, and arabinose, and the molar ratio was 10.77:25.22:2.37:15.74:125.39:48.62:34.70. The polyphenols comprised chlorogenic acid, 4-dicaffeoylquinic acid, caffeic acid, 1,3-dicaffeoylqunic acid, isochlorogenic acid B, isochlorogenic acid A, cynarin, and isochlorogenic acid C, and the contents were 0.503, 0.029, 0.022, 0.017, 0.008, 0.162, 1.621, 0.030 mg/g, respectively. This study also showed that the carbohydrates and polyphenols in artichoke bud could be important natural antioxidants, and the composition analysis of HPLC provided directions for their future research. Carbohydrates and polyphenols in artichoke buds can be separated and enriched using the optimized process technology, and it is an effective means of extracting ingredients from plants.


Assuntos
Antioxidantes , Cynara scolymus , Antioxidantes/química , Polifenóis/análise , Cynara scolymus/química , Sulfato de Amônio , Pós , Galactose/química , Água , Extratos Vegetais/farmacologia , Extratos Vegetais/química
13.
Medicina (Kaunas) ; 58(9)2022 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-36143853

RESUMO

Background and objective: Lonicera japonica Flos (LJF) is a well-known traditional herbal medicine that has been used as an anti-inflammatory, antibacterial, antiviral, and antipyretic agent. The potent anti-inflammatory and other ethnopharmacological uses of LJF make it a potential medicine for the treatment of nonalcoholic fatty liver disease (NAFLD). This research is to explore the mechanisms involved in the activity of LJF against NAFLD using network integration and experimental pharmacology. Materials and methods: The possible targets of LJF involved in its activity against NAFLD were predicted by matching the targets of the active components in LJF with those targets involved in NAFLD. The analysis of the enrichment of GO functional annotations and KEGG pathways using Metascape, followed by constructing the network of active components-targets-pathways using Cytoscape, were carried out to predict the targets. Molecular docking studies were performed to further support the involvement of these targets in the activity of LJF against NAFLD. The shortlisted targets were confirmed via in vitro studies in an NAFLD cell model. Results: A total of 17 active components in LJF and 29 targets related to NAFLD were predicted by network pharmacology. Molecular docking studies of the main components and the key targets showed that isochlorogenic acid B can stably bind to TNF-α and CASP3. In vitro studies have shown that LJF down-regulated the TNF-α and CASP3 expression in an NAFLD cell model. Conclusions: These results provide scientific evidence for further investigations into the role of LJF in the treatment of NAFLD.


Assuntos
Antipiréticos , Medicamentos de Ervas Chinesas , Lonicera , Hepatopatia Gordurosa não Alcoólica , Antibacterianos/uso terapêutico , Antipiréticos/uso terapêutico , Antivirais/uso terapêutico , Caspase 3 , Medicamentos de Ervas Chinesas/uso terapêutico , Humanos , Simulação de Acoplamento Molecular , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Fator de Necrose Tumoral alfa
14.
Phys Chem Chem Phys ; 23(14): 8936, 2021 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-33876053

RESUMO

Correction for 'Analysis and visualization of energy densities. I. Insights from real-time time-dependent density functional theory simulations' by Junjie Yang et al., Phys. Chem. Chem. Phys., 2020, 22, 26838-26851, DOI: .

15.
J Thromb Thrombolysis ; 52(3): 941-948, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33544285

RESUMO

We highlight two distinct cases of myocardial infarction occurring concurrently with anaphylaxis at our centre in Singapore. The first case had cardiac symptoms and electrocardiogram changes concomitant with his anaphylaxis presentation, suggestive of Kounis syndrome, while the second case presented with anaphylaxis and only developed cardiac symptoms and electrocardiogram changes after treatment with intramuscular epinephrine, suggestive of epinephrine-induced myocardial infarction. Both these conditions are uncommon and under-recognised, and we review the current literature to compare the similarities and differences in their clinical manifestations, pathophysiology, and management. Kounis syndrome occurs secondary to mast cell degranulation ultimately resulting in coronary vasospasm, platelet activation and inflammatory response, whereas epinephrine causes platelet aggregation. Therefore, treatment priorities of Kounis syndrome are treatment of allergy, treatment of vasospasm, and treatment with anti-platelet therapy and revascularization if coronary plaques are present. For epinephrine-induced myocardial infarction, after epinephrine treatment is discontinued, considerations in management are re-vascularisation or pharmacotherapy. Further research will help with better understanding of both conditions and formulation of clinical management guidelines.


Assuntos
Anafilaxia , Síndrome de Kounis , Infarto do Miocárdio , Anafilaxia/induzido quimicamente , Eletrocardiografia , Epinefrina , Humanos , Síndrome de Kounis/tratamento farmacológico , Infarto do Miocárdio/induzido quimicamente , Infarto do Miocárdio/tratamento farmacológico
16.
J Chem Phys ; 155(6): 064107, 2021 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-34391367

RESUMO

Inspired by the formulation of quantum-electrodynamical time-dependent density functional theory (QED-TDDFT) by Rubio and co-workers [Flick et al., ACS Photonics 6, 2757-2778 (2019)], we propose an implementation that uses dimensionless amplitudes for describing the photonic contributions to QED-TDDFT electron-photon eigenstates. This leads to a Hermitian QED-TDDFT coupling matrix that is expected to facilitate the future development of analytic derivatives. Through a Gaussian atomic basis implementation of the QED-TDDFT method, we examined the effect of dipole self-energy, rotating-wave approximation, and the Tamm-Dancoff approximation on the QED-TDDFT eigenstates of model compounds (ethene, formaldehyde, and benzaldehyde) in an optical cavity. We highlight, in the strong coupling regime, the role of higher-energy and off-resonance excited states with large transition dipole moments in the direction of the photonic field, which are automatically accounted for in our QED-TDDFT calculations and might substantially affect the energies and compositions of polaritons associated with lower-energy electronic states.

17.
Phys Chem Chem Phys ; 22(46): 26852-26864, 2020 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-33216085

RESUMO

Inspired by the analysis of Kohn-Sham energy densities by Nakai and coworkers, we extended the energy density analysis to linear-response time-dependent density functional theory (LR-TDDFT) calculations. Using ethylene-tetrafluoroethylene and oxyluciferin-water complexes as examples, distinctive distribution patterns were demonstrated for the excitation energy densities of local excitations (within a molecular fragment) and charge-transfer excitations (between molecular fragments). It also provided a simple way to compute the effective energy of both hot carriers (particle and hole) from charge-transfer excitations via an integration of the excitation energy density over the donor and acceptor grid points.

18.
Phys Chem Chem Phys ; 22(46): 26838-26851, 2020 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-33170198

RESUMO

In this article, we report a scheme to analyze and visualize the energy density fluctuations during the real-time time-dependent density functional theory (RT-TDDFT) simulations. Using Ag4-N2 complexes as examples, it is shown that the grid-based Kohn-Sham energy density can be computed at each time step using a procedure from Nakai and coworkers. Then the instantaneous energy of each molecular fragment (such as Ag4 and N2) can be obtained by partitioning the Kohn-Sham energy densities using Becke or fragment-based Hirshfeld (FBH) scheme. A strong orientation-dependence is observed for the energy flow between the Ag4 cluster and a nearby N2 molecule in the RT-TDDFT simulations. Future applications of such an energy density analysis in electron dynamics simulations are discussed.

19.
J Cell Mol Med ; 23(10): 6554-6564, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31402547

RESUMO

Osteoarthritis (OA) is a prevalent degenerative joint disease whose pathogenesis remains unclear. The research aims to investigate the roles of Circ_0136474/miR-127-5p/MMP-13 axis in OA. Differentially expressed circRNAs and miRNAs in OA cartilage tissue were screened out and visualized by R project based on RNA-seq data and microarray data respectively. qRT-PCR was carried out for detection of relative expression levels of Circ_0136474, miR-127-5p, MMP-13 and other inflammatory factors and Western blot analysis was conducted to detect the protein expression level of MMP-13. CCK-8 assay and flow cytometry were conducted to determine cell proliferation and cell apoptotic ability respectively. RNA-fluorescence in situ hybridization (RNA-FISH) experiments were conducted to confirm the immune-localization of the Circ_0136474 and MMP-13 in human tissues. Targeted relationships were predicted by bioinformatic analysis and verified by dual-luciferase reporter assay. Our findings revealed that the expression levels of both Circ_0136474 and MMP-13 in OA cartilage tissue were significantly higher than that in normal cartilage tissue. Circ_0136474 could suppress cell proliferation by facilitating MMP-13 expression and suppressing miR-127-5p expression in OA. Overexpression of miR-127-5p negatively regulated MMP-13 expression to enhance cell proliferation. Our study demonstrated that Circ_0136474 and MMP-13 suppressed cell proliferation, while enhanced cell apoptosis by competitive binding to miR-127-5p in OA, which may well provide us with a new therapeutic strategy for osteoarthritis.


Assuntos
Cartilagem/metabolismo , Metaloproteinase 13 da Matriz/metabolismo , MicroRNAs/metabolismo , Osteoartrite/metabolismo , RNA Circular/metabolismo , Apoptose/genética , Ligação Competitiva , Proliferação de Células/genética , Células Cultivadas , Colágeno Tipo II/metabolismo , Inativação Gênica , Humanos , Hibridização in Situ Fluorescente , Interleucina-17/metabolismo , Interleucina-1beta/metabolismo , Metaloproteinase 13 da Matriz/genética , MicroRNAs/genética , Análise de Sequência com Séries de Oligonucleotídeos , Osteoartrite/enzimologia , Osteoartrite/genética , RNA Circular/genética , RNA-Seq , Fator de Necrose Tumoral alfa/metabolismo , Regulação para Cima
20.
J Gene Med ; 21(11): e3115, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31348845

RESUMO

BACKGROUND: Genome editing using the CRISPR/Cas9 system is now well documented in basic studies and is expected to be applied to gene therapy. Simultaneous expression of multiplex guide RNA (gRNA) and Cas9/Cas9 derivative is attractive for the efficient knockout of genes and a safe double-nicking strategy. However, such use is limited because highly multiplex gRNA-expressing units are difficult to maintain stably in plasmids as a result of deletion via homologous recombination. METHODS: Lambda in vitro packaging was used instead of transformation for the construction and preparation of large, cos-containing plasmid (cosmid). Polymerase chain reaction fragments containing multiplex gRNA units were obtained using the Four-guide Tandem method. Transfection was performed by lipofection. RESULTS: We constructed novel cosmids consisting of linearized plasmid-DNA fragments containing up to 16 copies of multiplex gRNA-expressing units as trimer or tetramer (polygonal cosmids). These cosmids behaved as if they were monomer plasmids, and multiplex units could stably be maintained and amplified with a lack of deletion. Surprisingly, the deleted cosmid was removed out simply by amplifying the cosmid stock using lambda packaging. The DNA fragments containing multiplex gRNA-units and Cas9 were transfected to 293 cells and were found to disrupt the X gene of hepatitis B virus by deleting a large region between the predicted sites. CONCLUSIONS: We present a simple method for overcoming the problem of constructing plasmids stably containing multiplex gRNA-expressing units. The method may enable the production of very large amounts of DNA fragments expressing intact, highly-multiplex gRNAs and Cas9/Cas9 derivatives for safe and efficient genome-editing therapy using non-viral vectors.


Assuntos
Sistemas CRISPR-Cas , Cosmídeos/genética , Amplificação de Genes , Edição de Genes , Expressão Gênica , RNA Guia de Cinetoplastídeos , Bacteriófago lambda/genética , Ordem dos Genes , Marcação de Genes , Vírus da Hepatite B/genética , Humanos , Deleção de Sequência , Transfecção
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