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1.
Mol Neurobiol ; 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38724867

RESUMEN

Helicid (HEL) has been found to possess antidepressant pharmacological activity. The paper was to testify to the precise molecular mechanism through which HEL regulates lncRNA-NONRATT030918.2 to exert an antidepressant impression in depression models. A depression model stimulated using chronic unpredictable mild stress (CUMS) was created in rats, and the depressive state of the rats was assessed through behavioral experiments. Additionally, an in vitro model of PC12 cells induced by corticosterone (CORT) was established, and cytoactive was tested using the CCK8. The subcellular localization of the NONRATT030918.2 molecule was confirmed through a fluorescence in situ hybridization experiment. The relationship between NONRATT030918.2, miRNA-128-3p, and Prim1 was analyzed using dual-luciferase reporter gene assay, RNA Binding Protein Immunoprecipitation assay, and RNA pull-down assay. The levels of NONRATT030918.2, miRNA-128-3p, and Prim1 were tested using Q-PCR. Furthermore, the levels of Prim1, Bax, Bcl-2, and caspase3 were checked through Western blot. The HEL can alleviate the depression-like behavior of CUMS rats (P < 0.05), and reduce the mortality of hippocampal via downregulating the level of NONRATT030918.2 (P < 0.05). In CORT-induced PC12 cells, intervention with HEL led to decreased expression of NONRATT030918.2 and Prim1 (P < 0.05), as well as increased expression of miRNA-128-3p (P < 0.05). This suggests that HEL regulates the expression of NONRATT030918.2 to upregulate miRNA-128-3p (P < 0.05), which in turn inhibits CORT-induced apoptosis in PC12 cells by targeting Prim1 (P < 0.05). The NONRATT030918.2/miRNA-128-3p/Prim1 axis could potentially serve as a crucial regulatory network for HEL to exert its neuroprotective effects.

2.
J Hazard Mater ; 441: 129920, 2023 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-36099739

RESUMEN

Phenanthrene (PTH) and 9-phenanthrol (9-PTH) exhibited severe health threats and ecological hazards, for this reason, exploring a high-efficient removing strategy for PTH and 9-PTH could be considered of great urgency. Herein the 4,4'-biphenyldicarboxaldehyde m-phenylenediamine Schiff base magnetic polymer (magnetic BIPH-PHEN) was successfully fabricated via Schiff base polycondensation reaction and the subsequently one-pot embedded method. The mutual aromatic nucleus of BIPH-PHEN polymer and PTH/9-PTH could form π-π interaction, thus improving the capture ability, the embedded Fe3O4 nanoparticles provided the possibility for rapid separation. The physical and chemical properties of the magnetic BIPH-PHEN were systematically characterized. The removal rate of magnetic BIPH-PHEN towards PTH and 9-PTH was 85.65 % and 98.52 %, respectively (PTH or 9-PTH: 8 mg/L; Adsorbent: 0.2 g/L). The DFT calculations including energy calculations and electrostatic potential distribution analyzed the different bonding modes and proposed the most possible bonding modes in the adsorbent/adsorbate system. Moreover, the LUMO and HOMO orbits combined with energy gaps analysis proved the existence and specific types of the π-π interaction. The monolayer adsorption occurred on the homogeneous magnetic BIPH-PHEN surface, simultaneously the chemisorption was dominant. This work not only proposed new sights on assembling magnetic Schiff base polymer for removing polycyclic aromatic hydrocarbons, but also provided a deeper understanding of intramolecular interactions.


Asunto(s)
Fenantrenos , Hidrocarburos Policíclicos Aromáticos , Adsorción , Teoría Funcional de la Densidad , Fenilendiaminas , Hidrocarburos Policíclicos Aromáticos/análisis , Polímeros/química , Bases de Schiff/química , Electricidad Estática
3.
Phys Chem Chem Phys ; 25(1): 759-767, 2022 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-36508170

RESUMEN

The structural phase transition (SPT) and metal-insulator phase transition (MIT) always occur simultaneously upon heating from the low-temperature insulator M1 phase to the high-temperature metal R phase in vanadium dioxide, and it is still unclear which one of Mott correlation and Peierls distortion plays a decisive role in the thermally induced phase transition (PT) since 1959. Our density functional theory (DFT)-based calculations revealed that the intermediate phase in the PT, the so-called monoclinic metal phase, is a zero indirect band gap semimetal (P21/c space group) with a pseudo gap (199 meV). From the M1 phase to the monoclinic metal phase, the band gap decreases gradually to zero, and the bonding lengths between vanadium-vanadium atoms remain nearly constant. The SPT and MIT from the intermediate structure to the R phase occur simultaneously with a sudden change of bonding lengths between vanadium-vanadium atoms, in which electrons can jump down rather than jump up to the conduction band minimum (CBM) from the valence band maximum (VBM) under thermal fluctuation in order to lower the total energy of the system to push forward the occurrence of PT. The electron jumping does not require additional energy from Coulomb repulsion between electrons even though it is always present. This SPT is a typical Peierls PT or a pseudo Mott PT rather than an actual Mott PT in the each of the two stages. Our conclusions provide a new understanding of SPT and MIT in vanadium dioxide that has been debated for more than 80 years.

4.
J Hazard Mater ; 422: 126948, 2022 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-34449349

RESUMEN

Phenanthrene (PHE), as one of representative polycyclic aromatic hydrocarbons (PAHs) can cause serious adverse effects on human health, developing effective adsorbents to alleviate PHE contamination is in urgent demand. A novel Fe3O4-SiO2-Dimethoxydiphenylsilane (Fe3O4-SiO2-2DMDPS) nanocomposite was fabricated from encapsulation and grafting process. Magnetic Fe3O4 nanoparticles were served as preliminary matrix material, SiO2 was used to link the magnetic oxide and provide hydroxyl groups for proceeding the silane coupling reaction subsequently, and the aromatic rings in DMDPS could provide active sites for PHE adsorption via π-π interaction. SEM-EDS, TEM, BET, VSM, XRD, FTIR, Raman, Zeta potential, and XPS techniques were used to characterize magnetic nanocomposite. The prepared Fe3O4-SiO2-2DMDPS exhibited an excellent adsorption performance towards PHE, it could maintain 75.97% adsorption capacity after four regeneration cycles. Homogeneous adsorption acted crucial role in the whole adsorption process and film diffusion was the rate-controlling procedure. Theoretical calculations put forward the most favorable bonding modes between Fe3O4-SiO2-2DMDPS and PHE molecules, confirmed the π-π interaction was valid and it usually existed in the form of parallel-displaced. This work might aid us to develop effective modification strategy for Fe3O4 nanoparticles and expand its application in the PAHs removing field.


Asunto(s)
Nanocompuestos , Fenantrenos , Contaminantes Químicos del Agua , Adsorción , Humanos , Modelos Teóricos , Compuestos de Organosilicio , Dióxido de Silicio , Contaminantes Químicos del Agua/análisis
5.
J Healthc Eng ; 2021: 7168397, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34931140

RESUMEN

Background: Increasing evidence has shown that apoptosis in the hippocampus is closely related to depressive-like behavior. We previously reported that helicid had good antidepressant activities, which manifested as the alleviation of depression-like behaviors and the reversal of the high expression of neurocalcin delta (NCALD) in chronic unpredictable mild stress (CUMS) rats. The aim of this study was, therefore, to characterize the antidepressant-like effects and underlying mechanism of helicid on CUMS rats by silencing NCALD and using rescue experiments. Methods: We developed the CUMS rat model using CUMS stimulation from week 0 to week 6. The rats were treated with helicid, or NCALD silenced, then we overexpressed NCALD using adeno-associated virus. We also measured the protein levels of sGCα1, sGCß1, PKG1/2, and cleaved caspase-3 in hippocampal tissues using western blotting and measured cGMP using an ELISA. Results: Treating CUMS rats by silencing NCALD or by the administration of helicid improved the depressive-like behavior. The levels of proteins, including sGC, PKG, cleaved caspase-3, and cGMP, in hippocampus all decreased. NCALD overexpression reversed these decreases and reversed the alleviation of depression-like behaviors in CUMS rats. Limitation. We only detected the antidepressant effects of helicid in the hippocampus; therefore, other parts of brain should also be studied. Conclusions: Inhibition of NCALD, as well as helicid administration, alleviated antidepressant-like behavior by regulating the expressions of apoptotic cytokines and the sGC/cGMP/PKG signaling pathway. Overexpressing NCALD reversed the amelioration effects of silenced NCALD and helicid administration.


Asunto(s)
Depresión , Neurocalcina , Animales , Benzaldehídos , Depresión/tratamiento farmacológico , Neurocalcina/metabolismo , Ratas , Ratas Sprague-Dawley , Transducción de Señal , Estrés Psicológico/metabolismo , Estrés Psicológico/terapia
6.
Phys Chem Chem Phys ; 21(29): 16213-16222, 2019 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-31298246

RESUMEN

The electronic structure and magnetic properties of ten formamidinium transition metal iodides in the ground state and under strain have been studied. These formamidinium transition metal iodides have a stable cubic perovskite structure. In the ground state, FAVI3 is a spin gapless semiconductor, and FAScI3, FATiI3, FACrI3, FAFeI3, FACoI3 and FANiI3 are ferromagnetic half-metals. They all have 100% spin polarization and integer total magnetic moment. Under the action of strain, the high spin polarization of some formamidinium transition metal iodides can still be well maintained, and several novel spin gapless semiconductors such as FATiI3, FAFeI3 and FACoI3 have been discovered. Magnetic studies show that these formamidinium transition metal iodides with half-metal, semiconductor and spin-gapless semiconductor properties have integral total magnetic moments under strain ranging from -10.0% to 10.0%. These newly discovered half-metallic ferromagnetic materials and spin gapless semiconductors have broad application prospects in the field of spintronics due to their high spin polarization.

7.
J Chem Phys ; 140(9): 094301, 2014 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-24606355

RESUMEN

The first theoretical exploration of superhalogen properties of polynuclear structures based on pseudohalogen ligand is reported here via a case study on eight triply-bridged [Mg2(CN)5](-) clusters. From our high-level ab initio results, all these clusters are superhalogens due to their high vertical electron detachment energies (VDE), of which the largest value is 8.67 eV at coupled-cluster single double triple (CCSD(T)) level. Although outer valence Green's function results are consistent with CCSD(T) in most cases, it overestimates the VDEs of three anions dramatically by more than 1 eV. Therefore, the combined usage of several theoretical methods is important for the accuracy of purely theoretical prediction of superhalogen properties of new structures. Spatial distribution of the extra electron of high-VDE anions here indicates two features: remarkable aggregation on bridging CN units and non-negligible distribution on every CN unit. These two features lower the potential and kinetic energies of the extra electron respectively and thus lead to high VDE. Besides superhalogen properties, the structures, relative stabilities and thermodynamic stabilities with respect to detachment of CN(-1) were also investigated for these anions. The collection of these results indicates that polynuclear structures based on pseudohalogen ligand are promising candidates for new superhalogens with enhanced properties.

8.
J Chem Phys ; 139(5): 054305, 2013 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-23927260

RESUMEN

The structures, relative stabilities, vertical electron detachment energies, and magnetic properties of a series of trinuclear clusters are explored via combined broken-symmetry density functional theory and ab initio study. Several exchange-correlation functionals are utilized to investigate the effects of different halogen elements and central atoms on the properties of the clusters. These clusters are shown to possess stronger superhalogen properties than previously reported dinuclear superhalogens. The calculated exchange coupling constants indicate the antiferromagnetic coupling between the transition metal ions. Spin density analysis demonstrates the importance of spin delocalization in determining the strengths of various couplings. Spin frustration is shown to occur in some of the trinuclear superhalogens. The coexistence of strong superhalogen properties and spin frustration implies the possibility of trinuclear superhalogens working as the building block of new materials of novel magnetic properties.

9.
Huan Jing Ke Xue ; 34(4): 1340-4, 2013 Apr.
Artículo en Chino | MEDLINE | ID: mdl-23798111

RESUMEN

In order to discuss the potential ecological risk of heavy metals of the typical dredged mud in Shanghai, the Hakanson potential ecological risks method was used to analyse and assess the potential ecological risks of heavy metals, including Hg, Cd, Cu, Pb, As,Cr and Zn in dredged mud from the following three areas-the dock apron of Huangpu River, the mouth of the Yangtze River and inland waterways. The results showed that the mean values of ecological risk index (Er(i)) of the seven heavy metals are 20.05, 17.49, 8.82, 5.71, 4.68, 1.74 and 1.13, respectively, all of which belonged to the low ecological risk; Cd (one location in inland waterways) and Hg (three locations in the mouth of the Yangtze River and one location in inland waterways) are the most hazardous elements, with the Er(i) > 40, which belonged to the medium ecological risk or the high ecological risk, and other elements belonged to the low ecological risk. From the results of ecological risk indices(ERI) of the heavy metals in Shanghai dredged mud, the risk of the heavy metals belonged to the low ecological risk. The ERI of inland waterways, the mouth of the Yangtze River and the dock apron of the Huangpu River were 81.4, 57.7 and 52.5, respectively, which all belong to the low ecological risk.


Asunto(s)
Ecosistema , Sedimentos Geológicos/química , Metales Pesados/análisis , Agua de Mar/análisis , Contaminantes Químicos del Agua/análisis , China , Ciudades , Monitoreo del Ambiente/métodos , Océanos y Mares , Medición de Riesgo
10.
Guang Pu Xue Yu Guang Pu Fen Xi ; 31(7): 1804-8, 2011 Jul.
Artículo en Chino | MEDLINE | ID: mdl-21942028

RESUMEN

To understand the relationship between the vibrational spectra and the geometry structure of 3-amino-2, 5-dichlorobenzoic acid (3A2, 5DBA) essentially, geometry optimizations and vibrational frequencies calculation of 3A2, 5DBA were performed at Hartree-Fock (HF) and Becke's three-parameter hybrid functional (B3) for the exchange part and the Lee-Yang-Parr (LYP) correlation function (B3LYP) level using 6-311G(d, p) basis set, respectively. The structural information and 45-complete normal vibrational modes of 3A2, 5DBA were obtained. Comparing the computational geometric parameters of 3A2, 5DBA with the values observed in experimental measurement of benzoic acid as well as the computed vibrational frequencies of 3A2, 5DBA with the reported data of pertinent literature, it was revealed that the results coming from B3LYP/6-311G(d, p) are more reasonable than those by HF/6-311G(d, p). Taking into account the difference between the computed 3A2, 5DBA molecule and the experimental measured sample, the calculated vibrational frequencies were reasonably scaled. Under the B3LYP/6-311G(d, p) method, the scale factor was 1.0013 for the vibrational frequencies with wave numbers <800 cm(-1), while the scale factor was 0.9613 for the vibrational frequencies with wave numbers >800 cm(-1). With the help of Gaussian View software package, the theoretically calculated vibrational frequencies were assigned much more accurately. In addition, the vibrational analysis of substitutive groups and main functional groups of 3A2, 5DBA was carried out. Through the comparison of the calculated vibrational frequencies with the frequencies of 3A2, 5DBA observed in FTIR experiment, the authors found that the theoretically calculated vibrational frequencies scaled reasonably were in excellent agreement with the data coming from experimental measurements. Meanwhile, according to the related literature reports, it was shown that our work done in the paper about vibrational assignments and vibrational analysis of 3A2, 5DBA turned out to be reasonable.

11.
Guang Pu Xue Yu Guang Pu Fen Xi ; 31(1): 95-9, 2011 Jan.
Artículo en Chino | MEDLINE | ID: mdl-21428065

RESUMEN

Vanadium oxide films were deposited at different substrate temperatures up to 400 degrees C by DC magnetron sputtering, and through the method of the X-ray diffraction, electron scanning microscopy, infrared and Raman spectra, the present paper studies the structure properties of those films, and through the method of spectrum measuring and fitting, this paper studies the optical properties of the films. At low temperature of preparation the optical films have high optical transmittance. The films prepared at low substrate temperature (lower than 200 degrees C) have amorphous structure and some films prepared at high substrate temperatures (higher than 200 degrees C) have polycrystalline structure. The films' optical parameters were achieved by using classic model to fit the characteristic of transmittance.

12.
Guang Pu Xue Yu Guang Pu Fen Xi ; 31(12): 3190-3, 2011 Dec.
Artículo en Chino | MEDLINE | ID: mdl-22295757

RESUMEN

The authors synthesized the core-shell nanoparticles of SiO2-coated SiO2:Tb3+ by using sol-gel method (SiO2:Tb3+ @SiO2), and studied the influence of core-shell ratio and preparation craftwork on its luminescence properties. The photograph of TEM and EDS showed that SiO2:Tb3+ were coated successfully by SiO2. The authors found that the samples of SiO2:Tb3+ @SiO2 prepared by mixing of core and shell after shell aging with the ratio of core/shell being 1.2 g/25 mL had the stronger fluorescence intensity. Time-resolved spectra showed that the SiO2:Tb3+ @SiO2 had longer fluorescence life time than SiO2:Tb3+.

13.
J Phys Condens Matter ; 21(27): 275401, 2009 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-21828485

RESUMEN

Elastic properties of NaXH(4) (X = B, Al) have been studied by first-principles calculations using a projected augmented plane-wave approach. The calculated elastic constants compare favorably with experimental values. Our calculations show that the theoretically calculated elastic constants and bulk moduli have small values compared with those of typical metals and intermetallic compounds, which indicates that NaXH(4) (X = B, Al) are highly compressible. Comparison of bulk moduli B of different complex hydrides shows a correlation between B and the decomposition temperatures. Also, we calculated the elastic anisotropies and the Debye temperatures from the elastic constants.

14.
J Chem Phys ; 123(20): 204315, 2005 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-16351264

RESUMEN

Various structural possibilities for Al(n)B(m) (n=1-7, m=1-2) neutral isomers were investigated using B3LYP6-311G(d) and CCSD(T)6-311G(d) methods. Our calculations predicted the existence of a number of previously unknown isomers. The B atom favors to locate over/inside of all clusters in this series. All structures of the Al(n)B (n=2-7) may be derived from capping/putting a B atom over/inside the Al(n) cluster. All Al(n)B(2) (n=1-5) may be understood as two substitutions of Al atoms by B atoms in the Al(n+2) molecule. The strong B-B bond is a dominant factor in the building-up principle of mixed Al(n)B(2) neutral clusters. The second difference in energy showed that the Al(n)B(m) clusters with even n+m are more stable than those with odd n+m. Our results and analyses revealed that the mixed Al-B clusters exhibit aromatic behaviors.

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