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1.
Nano Lett ; 24(26): 8071-8079, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38901035

RESUMO

Single-atom nanozymes (SANs) are considered to be ideal substitutes for natural enzymes due to their high atom utilization. This work reported a strategy to manipulate the second coordination shell of the Ce atom and reshape the carbon carrier to improve the oxidase-like activity of SANs. Internally, S atoms were symmetrically embedded into the second coordination layer to form a Ce-N4S2-C structure, which reduced the energy barrier for O2 reduction, promoted the electron transfer from the Ce atom to O atoms, and enhanced the interaction between the d orbital of the Ce atom and p orbital of O atoms. Externally, in situ polymerization of mussel-inspired polydopamine on the precursor helps capture metal sources and protects the 3D structure of the carrier during pyrolysis. On the other hand, polyethylene glycol (PEG) modulated the interface of the material to enhance water dispersion and mass transfer efficiency. As a proof of concept, the constructed PEG@P@Ce-N/S-C was applied to the multimodal assay of butyrylcholinesterase activity.


Assuntos
Cério , Cério/química , Polietilenoglicóis/química , Oxirredutases/química , Oxirredutases/metabolismo , Butirilcolinesterase/química , Butirilcolinesterase/metabolismo , Polímeros/química , Indóis/química , Oxigênio/química , Oxirredução
2.
Nano Lett ; 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39007697

RESUMO

The technology of combining multiple emission centers to exploit white-light-emitting (WLE) materials by taking advantage of porous metal-organic frameworks (MOFs) is mature, but preparing undoped WLE MOFs remains a challenge. Herein, a pressure-treated strategy is reported to achieve efficient white photoluminescence (PL) in undoped [Zn(Tdc)(py)]n nanocrystals (NCs) at ambient conditions, where the Commission International del'Eclairage coordinates and color temperature reach (0.31, 0.37) and 6560 K, respectively. The initial [Zn(Tdc)(py)]n NCs exhibit weak-blue PL consisting of localized excited (LE) and planarized intramolecular charge transfer (PLICT) states. After pressure treatment, the emission contributions of LE and PLICT states are balanced by increasing the planarization of subunits, thereby producing white PL. Meanwhile, the reduction of nonradiative decay triggered by the planarized structure results in 5-fold PL enhancement. Phosphor-converted light-emitting diodes based on pressure-treated samples show favorable white-light characteristics. The finding provides a new platform for the development of undoped WLE MOFs.

3.
Small ; : e2400541, 2024 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-38644221

RESUMO

The high crystalline covalent triazine framework-1 (CTF-1), composed of alternating triazine and phenylene, has emerged as an efficient photocatalyst for solar-driven hydrogen evolution reaction (HER). However, it is of great challenge to further improve photocatalytic HER performance via increasing crystallinity due to its near-perfect crystallization. Herein, an alternative strategy of scaffold functionalization is employed to optimize the energy band structure of crystalline CTF-1 for boosting hydrogen-evolving activity. Guided by the computational predictions, versatile CTF-based polymer photocatalysts are prepared with different functional groups (OH, NH2, COOH) using binary polymerization for practical hydrogen production. Experiment evidence verifies that the introduction of a limited number of electron-donating groups is sufficient to maintain high crystallinity in CTF, modulate the band structure, broaden visible light absorption, and consequently enhance its photophysical properties. Notably, the functionalization with OH exhibits the most positive effect on CTF-1, delivering a photocatalytic activity with a hydrogen-producing rate exceeding 100 µmol h-1.

4.
J Nat Prod ; 87(2): 297-303, 2024 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-38308643

RESUMO

Three nor-sesquiterpenes, phellinharts A-C (1-3), isolated from Phellinus hartigii, exhibited unprecedented protoilludane and cerapicane-type structures. The structures of compounds 1-3 were elucidated via spectroscopic analysis, quantum chemical calculations, and X-ray diffraction. Potential biogenic pathways involving demethylation, ring cleavage, and rearrangement were proposed. Compounds 1-3 displayed potent anti-hypertrophic activities with low cytotoxicity (CC50 > 50 µM) in rat cardiomyocytes, underscoring their therapeutic potential.


Assuntos
Miócitos Cardíacos , Phellinus , Sesquiterpenos Policíclicos , Sesquiterpenos , Animais , Ratos , Estrutura Molecular , Sesquiterpenos/química
5.
Molecules ; 29(2)2024 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-38276602

RESUMO

A series of reported Pt(II) carbene complexes possibly have the ability to serve as the new generation of blue emitters in luminescent devices because of their narrow emission spectra, high photoluminescence quantum yields (PLQYs), and rigid molecular skeleton. However, the combination of all carbene ligands with different multidentate structures will affect the overall planarity and horizontal dipole ratio to varying degrees, but the specific extent of this effect has not previously been analyzed in detail. In this work, density functional computation is used to study a class of platinum tetracarbene bidentate complexes with similar absorption and emission band characteristics, which is the main reason for the remarkable difference in quantum efficiency due to subtle differences in electronic states caused by different ligands. From the calculation results, the major reason, which results in significantly decrease in quantum efficiency for [Pt(cyim)2]2+, is that [Pt(cyim)2]2+ can reach the non-radiative deactivation metal-centered d-d excited state through an easier pathway compared with [Pt(meim)2]2+. The result, based on changes in the dihedral angle between ligands, can achieve the goal of improving and designing materials by adjusting the degree of the dihedral angle. (meim: bis(1,1'-dimethyl-3,3'-methylene-diimidazoline-2,2'-diylidene); cyim: bis(1,1'-dicyclohexyl-3,3'-methylene-diimidazoline-2,2'-diylidene).

6.
Inorg Chem ; 62(35): 14216-14227, 2023 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-37615424

RESUMO

Novel endohedral metallofullerenes (EMFs), namely, Er2C2@C2v(5)-C80, Er2C2@Cs(6)-C82, Er2C2@Cs(15)-C84, Er2C2@C2v(9)-C86, Er2C2@Cs(15)-C86, and Er2C2@Cs(32)-C88, had been experimentally synthesized, and the unique structures and many fascinating properties had also been widely explored. Nevertheless, the position of the Er atoms inside the cage shows a severe disorder within the stable EMF monomer, which is difficult to understand and explain from the experimental point of view. In this work, based on the density functional theoretical calculations, the Er2C2@Cs(6)-C82 has 73 directional isomers and 2 Er atoms that are far beyond from Er-Er single bonding and tend to be close to the cage side (marked as "shell"), and the core (Er2C2 units) takes on a butterfly shape as generally revealed. The energy difference between any two of the isomers is in the range of 0.05 to 25.6 kcal/mol, indicating a relatively easy thermodynamic transition between the isomers. The other five Er carbide cluster EMFs (Er2C2@C2v(5)-C80, Er2C2@Cs(15)-C84, Er2C2@C2v(9)-C86, Er2C2@Cs(15)-C86, and Er2C2@Cs(32)-C88) are also studied in the same way, and 30, 37, 39, and 43 most stable Er-oriented sites inside the cage, respectively, are obtained. In addition, the shape of the Er2C2 gradually changed from butterfly to linear. Moreover, the electronic structure and molecular orbital analyses show that it is easy for Er2C2@C80-88 to form a charge transfer state of [Er2C2]4+@[C80-88]4- via the dynamic core-shell coordination equilibrium. Er2C2 with a steep drop in chemical stability is restricted to forming varying degrees of metastable states in the shell, determined by the shell size, to ensure the overall stability. The lowest unoccupied molecular orbital energy level of these EMFs is increased by 0.5-1.1 eV compared with fullerenes C80-88, potentially providing favorable conditions for suitable energy level matching with EMF as an electron acceptor used in organic solar cell devices.

7.
Phys Chem Chem Phys ; 25(37): 25871-25879, 2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37725156

RESUMO

Tri-(2,4,6-trichlorophenyl)methyl (TTM) based radicals can be promising in providing relatively high fluorescence quantum efficiency. In this study, we have evaluated the photoluminescence properties of a series of TTM-based radicals by means of DFT and TD-DFT methods. The optimized structures of the ground states (D0) and the first excited states (D1) of all the radicals are calculated and the computed emission bands are comparable with previous experimental results. knr is determined from transition dipole moments (µ12) and the energy gaps between D0 and D1 (ΔE), both of which can be regulated by the conjugated structures from the substituent groups. knr was derived from the mode-averaging method and is consistent with the experimental results. Factors influencing kr and knr, including the potential energy differences (ΔG0), the vibrational reorganization energies (λ) and the electron coupling term (Hab), are discussed. By comparing kr and knr in solvents with different polarities (cyclohexane, toluene, and chloroform), TTM based radicals in cyclohexane exhibit the most promising fluorescence efficiencies. Besides, two substituted radicals, namely 2Br-TTM-3PCz and 2F-TTM-3PCz, have been fabricated. The results show that fluorine atoms are able to increase ΔG0 and a considerably small knr has been predicted. We expect that our calculation can benefit the design of light-emitting molecules in further experiments.

8.
J Comput Assist Tomogr ; 47(6): 856-863, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37948359

RESUMO

OBJECTIVES: The aim of this study was to investigate the computed tomography (CT) features of recurrent acute pancreatitis (RAP) in the early phase and late phase. METHODS: Recurrent acute pancreatitis data were obtained over the past 5 years. Recurrent acute pancreatitis patients were divided into 2 groups according to the time from RAP onset to performing CT examination: the early phase (first week) and late phase (after the first week) based on the 2012 revised Atlanta classification (RAC). Evaluation and comparison of patients' demographic data, RAC, CT findings, CT severity index (CTSI) score, and extrapancreatic inflammation on CT (EPIC) score were conducted in the 2 groups. RESULTS: Hypertriglyceridemia was the most common cause of RAP in 679 of 686 patients (positive CT rate: 98.98%). Among 679 CT-positive patients, interstitial edematous pancreatitis and necrotizing pancreatitis accounted for 61.71% (419/679) and 38.29% (260/679), respectively. The CTSI and EPIC scores were higher in the late phase than in the early phase (both P 's < 0.05). The proportion of moderately severe and severe RAP patients based on RAC was higher in the late phase than in the early phase ( P < 0.05). Early-stage EPIC score was more accurate than CTSI and Acute Physiology and Chronic Health Evaluation (APACHE) II scores in predicting clinically severe RAP (EPIC vs CTSI; EPIC vs APACHE II, both P 's < 0.05). CONCLUSIONS: Recurrent acute pancreatitis is more severe in the late phase than in the early phase. The EPIC score is more indicative of clinically severe RAP than CTSI and APACHE II scores in the early phase of RAP.


Assuntos
Pancreatite Necrosante Aguda , Humanos , Doença Aguda , Índice de Gravidade de Doença , Tomografia Computadorizada por Raios X , Estudos Retrospectivos , Valor Preditivo dos Testes
9.
Mar Drugs ; 21(5)2023 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-37233493

RESUMO

Numerous compounds present in the ocean are contributing to the development of the biomedical field. Agarose, a polysaccharide derived from marine red algae, plays a vital role in biomedical applications because of its reversible temperature-sensitive gelling behavior, excellent mechanical properties, and high biological activity. Natural agarose hydrogel has a single structural composition that prevents it from adapting to complex biological environments. Therefore, agarose can be developed into different forms through physical, biological, and chemical modifications, enabling it to perform optimally in different environments. Agarose biomaterials are being increasingly used for isolation, purification, drug delivery, and tissue engineering, but most are still far from clinical approval. This review classifies and discusses the preparation, modification, and biomedical applications of agarose, focusing on its applications in isolation and purification, wound dressings, drug delivery, tissue engineering, and 3D printing. In addition, it attempts to address the opportunities and challenges associated with the future development of agarose-based biomaterials in the biomedical field. It should help to rationalize the selection of the most suitable functionalized agarose hydrogels for specific applications in the biomedical industry.


Assuntos
Materiais Biocompatíveis , Hidrogéis , Sefarose/química , Hidrogéis/química , Materiais Biocompatíveis/química , Engenharia Tecidual , Sistemas de Liberação de Medicamentos
10.
Int J Mol Sci ; 24(9)2023 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-37175416

RESUMO

Neurofilament light chain (NF-L) plays critical roles in synapses that are relevant to neuropsychiatric diseases. Despite postmortem evidence that NF-L is decreased in opiate abusers, its role and underlying mechanisms remain largely unknown. We found that the microinjection of the histone deacetylase (HDAC) inhibitor Trichostatin A (TSA) into the ventrolateral orbital cortex (VLO) attenuated chronic morphine-induced behavioral sensitization. The microinjection of TSA blocked the chronic morphine-induced decrease of NF-L. However, our chromatin immunoprecipitation (ChIP)-qPCR results indicated that this effect was not due to the acetylation of histone H3-Lysine 9 and 14 binding to the NF-L promotor. In line with the behavioral phenotype, the microinjection of TSA also blocked the chronic morphine-induced increase of p-ERK/p-CREB/p-NF-L. Finally, we compared chronic and acute morphine-induced behavioral sensitization. We found that although both chronic and acute morphine-induced behavioral sensitization were accompanied by an increase of p-CREB/p-NF-L, TSA exhibited opposing effects on behavioral phenotype and molecular changes at different addiction contexts. Thus, our findings revealed a novel role of NF-L in morphine-induced behavioral sensitization, and therefore provided some correlational evidence of the involvement of NF-L in opiate addiction.


Assuntos
Filamentos Intermediários , Morfina , Ratos , Animais , Morfina/farmacologia , Fosforilação , Ratos Sprague-Dawley , Aprendizagem , Inibidores de Histona Desacetilases/farmacologia
11.
Mol Pain ; 18: 17448069221087583, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35240891

RESUMO

Knee osteoarthritis (KOA) is a highly prevalent, chronic joint disorder, and it is a typical disease which can develop chronic pain. Our previous study has proved that endocannabinoid (2-AG)-CB1R-GABA-5-HT pathway is involved in electroacupuncture (EA) mediated inhibition of chronic pain. However, it is still unclear which among the 5-HT receptor subtype is involved in EA evoked 5-HT mediated inhibition of chronic pain in the dorsal spinal cord. 5-HT2A is a G protein-coupled receptor and it is involved in 5-HT descending pain modulation system. We found that EA treatment at frequency of 2 Hz +1 mA significantly increased the expression of 5-HT2A receptor in the dorsal spinal cord and intrathecal injection of 5-HT2A receptor antagonist or agonist reversed or mimicked the analgesic effect of EA in each case respectively. Intrathecal injection of a selective GABAA receptor antagonist Bicuculline also reversed the EA effect on pain hypersensitivity. Additionally, EA treatment reversed the reduced expression of GABAA receptor and KCC2 in the dorsal spinal cord of KOA mice. Furthermore, we demonstrated that intrathecal 5-HT2A receptor antagonist/agonist reversed or mimicked the effect of EA up-regulate of KCC2 expression, respectively. Similarly, intrathecal injection of PLC and PKC inhibitors prevented both anti-allodynic effect and up-regulation of KCC2 expression by EA treatment. Our data suggest that EA treatment up-regulated KCC2 expression through activating 5-HT2A-Gq-PLC-PKC pathway and enhanced the inhibitory function of GABAA receptor, thereby inhibiting chronic pain in a mouse model of KOA.


Assuntos
Dor Crônica , Eletroacupuntura , Osteoartrite do Joelho , Simportadores , Animais , Dor Crônica/metabolismo , Dor Crônica/terapia , Camundongos , Osteoartrite do Joelho/metabolismo , Ratos , Ratos Sprague-Dawley , Receptor 5-HT2A de Serotonina/metabolismo , Receptores de GABA-A/metabolismo , Serotonina/metabolismo , Medula Espinal/metabolismo , Simportadores/metabolismo
12.
Small ; 18(11): e2107268, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35038228

RESUMO

It is an effective strategy to develop novel electrocatalysts with controllable defects to enhance their electrocatalytic activity and stability. However, how to precisely design these catalysts on the atom scale remains very difficult. Herein, several vacancy-dependent CoZnx Mn2-x O4 catalysts are prepared through tailoring the concentration of Zn ions. The in situ activation of the obtained products accelerates the surface reconstruction. The superior electrocatalytic performance can be ascribed to the formations of MOOH (Mn, Co) active species and abundant oxygen vacancies, which are comparable to noble IrO2 and Pt/C catalysts. Zn-CoMn2 O4 -1.5 catalyst delivers a cell voltage of 1.63 V and long durability. Density functional theory calculations demonstrate that the appropriate Zn ion doping can improve the density states of p electron on the surface of catalysts significantly and benefit the d-band center closing to Fermi level, suggesting their high charge carrier density and low adsorption energy.

13.
Phys Chem Chem Phys ; 24(9): 5690-5699, 2022 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-35187550

RESUMO

To combine both electride and alkalide characteristics in one molecular switch, it is shown herein that the phenalenyl radical and the M3 ring (M3-PHY, M = Li, Na, and K) stacked with parallel and vertical geometries are good candidates. The former geometry is the superalkali electride e-⋯M3+-PHY while the latter geometry is the superalkalide Mδ--M2(1-δ)+-PHY-. The superalkalide Mδ--M2(1-δ)+-PHY- may isomerize to the superalkali electride e-⋯M3+-PHY (M = Li, Na, and K) using suitable long-wavelength irradiation, while the latter may isomerize to the former with suitable short-wavelength irradiation. Also, applying suitable oriented external electric fields can drive the superalkalide Mδ-M2(1-δ)+-PHY- to change into the superalkali electride e-⋯M3+-PHY (M = Li, Na, and K). The differences in the static and dynamic first hyperpolarizability (ß0) values between them were also studied.

14.
Mar Drugs ; 20(2)2022 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-35200655

RESUMO

As an important enzyme involved in the marine carbon cycle, alginate lyase has received extensive attention because of its excellent degradation ability on brown algae, which is widely utilized for alginate oligosaccharide preparation or bioethanol production. In comparison with endo-type alginate lyases (PL-5, PL-7, and PL-18 families), limited studies have focused on PL-17 family alginate lyases, especially for those with special characteristics. In this study, a novel PL-17 family alginate lyase, Aly23, was identified and cloned from the marine bacterium Pseudoalteromonas carrageenovora ASY5. Aly23 exhibited maximum activity at 35 °C and retained 48.93% of its highest activity at 4 °C, representing an excellent cold-adaptation property. Comparative molecular dynamics analysis was implemented to explore the structural basis for the cold-adaptation property of Aly23. Aly23 had a high substrate preference for poly ß-D-mannuronate and exhibited both endolytic and exolytic activities; its hydrolysis reaction mainly produced monosaccharides, disaccharides, and trisaccharides. Furthermore, the enzymatic hydrolyzed oligosaccharides displayed good antioxidant activities to reduce ferric and scavenge radicals, such as hydroxyl, ABTS+, and DPPH. Our work demonstrated that Aly23 is a promising cold-adapted biocatalyst for the preparation of natural antioxidants from brown algae.


Assuntos
Antioxidantes/farmacologia , Oligossacarídeos/farmacologia , Polissacarídeo-Liases/metabolismo , Pseudoalteromonas/metabolismo , Antioxidantes/metabolismo , Dissacarídeos/metabolismo , Sequestradores de Radicais Livres/metabolismo , Sequestradores de Radicais Livres/farmacologia , Hidrólise , Simulação de Dinâmica Molecular , Monossacarídeos/metabolismo , Oligossacarídeos/metabolismo , Polissacarídeo-Liases/isolamento & purificação , Temperatura , Trissacarídeos/metabolismo
15.
Mar Drugs ; 20(12)2022 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-36547930

RESUMO

κ-carrageenases are members of the glycoside hydrolase family 16 (GH16) that hydrolyze sulfated galactans in red algae, known as κ-carrageenans. In this study, a novel κ-carrageenase gene from the marine bacterium Rhodopirellula sallentina SM41 (RsCgk) was discovered via the genome mining approach. There are currently no reports on κ-carrageenase from the Rhodopirellula genus, and RsCgk shares a low identity (less than 65%) with κ- carrageenase from other genera. The RsCgk was heterologously overexpressed in Escherichia coli BL21 and characterized for its enzymatic properties. RsCgk exhibited maximum activity at pH 7.0 and 40 °C, and 50% of its initial activity was retained after incubating at 30 °C for 2 h. More than 70% of its activity was maintained after incubation at pH 6.0-8.0 and 4 °C for 24 h. As a marine derived enzyme, RsCgk showed excellent salt tolerance, retaining full activity in 1.2 M NaCl, and the addition of NaCl greatly enhanced its thermal stability. Mass spectrometry analysis of the RsCgk hydrolysis products revealed that the enzyme had high degradation specificity and mainly produced κ-carrageenan disaccharide. Comparative molecular dynamics simulations revealed that the conformational changes of tunnel-forming loops under salt environments may cause the deactivation or stabilization of RsCgk. Our results demonstrated that RsCgk could be utilized as a potential tool enzyme for efficient production of κ-carrageenan oligosaccharides under high salt conditions.


Assuntos
Tolerância ao Sal , Cloreto de Sódio , Carragenina/química , Bactérias/metabolismo , Glicosídeo Hidrolases/metabolismo , Proteínas de Bactérias/metabolismo
16.
Fa Yi Xue Za Zhi ; 38(3): 355-359, 2022 Jun 25.
Artigo em Inglês, Zh | MEDLINE | ID: mdl-36221830

RESUMO

OBJECTIVES: To analyze the Nogo-P3 component of event-related potential (ERP) in the process of visual acuity processing, to provide electrophysiological evidence for objective evaluation of visual acuity. METHODS: Twenty-six subjects with no other ocular diseases except for ametropia were recruited, and all subjects had uncorrected visual acuity both eyes 1/10 (evaluated using Monoyer chart). Block letter E with different visual angles and directions were used as graphic stimuli. The Go/Nogo paradigm was used for ERP studies. The visual angle of Go stimulation angle was 1°15', Nogo stimuli were 1°15', 55', 24' and 15'. The visual acuity test was performed on each of the two naked eyes separately in all subjects, and the characteristics of the Nogo-P3 component were analyzed. RESULTS: The latency of Nogo-P3 showed no difference between the stimuli of 1°15' and 55', and between Nogo stimulation angle 24' and 15'. There was significant difference between Nogo stimulation angle 1°15' and 24', and between Nogo stimulation angle 1°15' and 15' (P<0.05). There was significant difference between Nogo stimulation angle 55' and 24', and between Nogo stimulation angle 55' and 15' (P<0.05). No significant differences were observed in the Nogo-P3 amplitude among Nogo stimulation. CONCLUSIONS: In the Go/Nogo paradigm, Nogo-P3 can reflect the cognitive response of subjects to Nogo stimulation, which can be used for objective evaluation of visual acuity.


Assuntos
Eletroencefalografia , Erros de Refração , Potenciais Evocados/fisiologia , Humanos , Estimulação Luminosa , Tempo de Reação/fisiologia , Acuidade Visual
17.
BMC Plant Biol ; 21(1): 443, 2021 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-34592922

RESUMO

BACKGROUND: Tiller number is a factor determining panicle number and grain yield in wheat (Triticum aestivum). Auxin plays an important role in the regulation of branch production. PIN-FORMED 1 (PIN1), an auxin efflux carrier, plays a role in the regulation of tiller number in rice (Oryza sativa); however, little is known on the roles of PIN1 in wheat. RESULTS: Nine homologs of TaPIN1 genes were identified in wheat, of which TaPIN1-6 genes showed higher expression in the stem apex and young leaf in wheat, and the TaPIN1-6a protein was localized in the plasma membrane. The down-expression of TaPIN1s increased the tiller number in TaPIN1-RNA interference (TaPIN1-RNAi) transgenic wheat plants, indicating that auxin might mediate the axillary bud production. By contrast, the spikelet number, grain number per panicle, and the 1000-grain weight were decreased in the TaPIN1-RNAi transgenic wheat plants compared with those in the wild type. In summary, a reduction of TaPIN1s expression increased the tiller number and grain yield per plant of wheat. CONCLUSIONS: Phylogenetic analysis and protein structure of nine TaPIN1 proteins were analyzed, and subcellular localization of TaPIN1-6a was located in the plasma membrane. Knock-down expression of TaPIN1 genes increased the tiller number of transgenic wheat lines. Our study suggests that TaPIN1s is required for the regulation of grain yield in wheat.


Assuntos
Regulação para Baixo , Proteínas de Membrana Transportadoras/metabolismo , Caules de Planta/crescimento & desenvolvimento , Sementes/crescimento & desenvolvimento , Triticum/crescimento & desenvolvimento , Triticum/genética , Triticum/metabolismo , Grão Comestível/genética , Grão Comestível/crescimento & desenvolvimento , Grão Comestível/metabolismo , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Caules de Planta/genética , Caules de Planta/metabolismo , Sementes/genética , Sementes/metabolismo
18.
Bioorg Med Chem Lett ; 43: 128079, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-33940136

RESUMO

In the current study, the interaction of SARS-CoV-2 protein (A and B chains of nsp13) with different recently synthesized phenolic compounds (Sreenivasulu et al., Synthetic Communications, 2020, 112-122) has been studied. The interactions have been investigated by using molecular docking, quantum chemical and molecular dynamics simulations methods. The molecular structures of all the ligands are studied quantum chemically in terms of their optimized structures, 3-D orbital distributions, global chemical descriptors, molecular electrostatic potential plots and HOMO-LUMO orbital energies. All the ligands show reasonably good binding affinities with nsp-13 protein. The ligand L2 shows to have better binding affinities to Chain A and Chain B of nsp13 protein, which are -6.7 and -6.4 kcal/mol. The study of intermolecular interactions indicates that L2 shows different hydrophobic and hydrogen bond interactions with both chains. Furthermore, molecular dynamic simulations of the nsp13-L2 complex are obtained over a time scale of 60 ns, which indicates its stability and flexibility behavior as assessed in terms of its RMSD and RMSF graphs. The ADMET analysis also shows no violation of Lipinski rule (RO5) by studied phenolic compounds. We believe that the current findings will be further confirmed by in vitro and in vivo studies of these recent phenolic compounds for their potential as inhibitors for SARS-Co-V-2 virus.


Assuntos
Antivirais/farmacologia , Tratamento Farmacológico da COVID-19 , COVID-19/virologia , Fenóis/farmacologia , SARS-CoV-2/efeitos dos fármacos , Antivirais/química , Humanos , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Estrutura Molecular , Fenóis/química , Teoria Quântica , SARS-CoV-2/isolamento & purificação , SARS-CoV-2/metabolismo
19.
Inorg Chem ; 60(3): 1480-1490, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33427451

RESUMO

Graphene materials with particular properties are proved to be beneficial to photoelectric devices, but there are rare reports on a positive effect by graphene on emissive layer materials of organic light-emitting diodes (OLEDs) previously. On the basis of the latest important experiments, an OLED device with the aid of graphene quantum dots shows the dawn of their application for luminescent materials. The luminescence performance has been improved, but the understanding of the internal excited-state radiation mechanism of the material needs further study. In this work, the Pt(II)-coordinated graphene quantum dot coplanar structures with different shapes are studied theoretically in detail, and the results present the improvement in phosphorescence under the promoted radiative decay and suppressed nonradiative decay. This composite combines the advantages of transition metal complexes and graphene quantum dots and also exhibits excellent properties in the light absorption region and carrier transportation for the OLED. This comprehensive theoretical calculation research can provide a comprehensive basis of the material design in the future.

20.
Phys Chem Chem Phys ; 23(8): 4681-4689, 2021 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-33595565

RESUMO

Computational analyses of the solid-state properties of triazasumanene (TAS), a C3-symmetric nitrogen-doped sumanene derivative, were carried out in this work. The present studies are mainly divided into two parts. In the first part, we demonstrated the differences in the interactions of the crystal packing between the racemic and the homochiral structures: the former having perpendicular columnar packing and the latter forming slipped helical packing. Two geometries of the TAS monomer, a theoretically optimized structure under vacuum and an X-ray crystal structure in experiment, were compared. It can be found that it is not the total interaction energy, but the local interactions (mainly the electrostatic interactions) of the molecular dimer that dominate the columnar stacking conformation. The second part involves the investigation of the potential charge transport properties of the crystals according to the semiclassical Marcus theory with the hopping mechanism using the simple dimer model. The charge transfer integrals of the two sets of dimers, racemic and homochiral dimer models, were compared as well. The calculation results show that the TAS racemic crystal was predicted to have an advantage of hole transport properties. The perpendicular columnar stacking of the homochiral conformation should essentially have better charge transport properties than the racemic conformation. It is reasonable to employ the simple dimer model built using optimized monomers under vacuum for the purpose of the prediction of the molecular packing conformation by IES calculation and the charge transport properties of the perpendicular columnar-stacking crystal. Our work provides a simple approach to the deep understanding of the structure-property relationship of bowl-shaped molecular systems in theory. It can help to facilitate the design and preparation of heteroatom-doped sumanene derivatives with perpendicular columnar stacking crystals as novel organic semiconductor materials.

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