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1.
Exp Parasitol ; 182: 45-53, 2017 Nov.
Article in English | MEDLINE | ID: mdl-28942050

ABSTRACT

Transforming growth factor-ß (TGF-ß) signaling pathway is documented to participate in liver fibrosis via multifactorial mechanisms. microRNA Let-7b (Let-7b) has been proved to alleviate cell fibrosis through regulating TGF-ß receptor I (TßRI), but whether it is involved in Schistosomiasis liver fibrosis (SLF) has not been determined. In the present, SLF mice model was used to investigate Let-7b's function and mechanism in SLF. We found that hepatic let-7b expression was continuously declined in SLF, accompanied by the induction of TGF-ß pathway molecules (TGF-ß1, TßRI), profibrogenic mediators (α-SMA, colla I), and Th1/Th2 cells response factors (IFN-γ, IL-4). When recombinant Lentivirus of let-7b (Lenti-let-7b) was transfected into S. japonicum-infected mice, the mice hepatic fibrosis was distinctly ameliorated, and TGF-ß1, TßRI, α-SMA, and colla I expressions were remarkly decreased, mice serum IL-4 and IFN-γ levels were reduced. Similarly, over-expression of let-7b down-regulated the expression of TßRI in THP-1 cells transfected with let-7b mimics, while TßRI was up-regulated after treated with let-7b inhibitor. These findings suggested that let-7b is a negative regulator to SLF through downregulating TßRI, and inhibits Th1 and Th2 type cell immune response. This provides a novel potential therapeutic strategy for SFL prevention.


Subject(s)
Lentivirus/metabolism , Liver Cirrhosis/prevention & control , MicroRNAs/metabolism , Schistosomiasis japonica/genetics , Animals , Cell Line , Cytokines/metabolism , Disease Models, Animal , Down-Regulation , Enzyme-Linked Immunosorbent Assay , Female , Gene Expression Regulation , Humans , Interferon-gamma/blood , Interleukin-4/blood , Lentivirus/genetics , Liver/metabolism , Liver/pathology , Liver Cirrhosis/parasitology , Mice , Mice, Inbred BALB C , MicroRNAs/genetics , Real-Time Polymerase Chain Reaction , Receptors, Transforming Growth Factor beta/genetics , Receptors, Transforming Growth Factor beta/metabolism , Schistosomiasis japonica/metabolism , Specific Pathogen-Free Organisms , Transforming Growth Factor beta/metabolism , Up-Regulation
2.
J Mol Model ; 28(11): 339, 2022 Oct 03.
Article in English | MEDLINE | ID: mdl-36190570

ABSTRACT

The geometric structure, energy properties, and electronic properties of the aerogen-bonding interaction formed by C2H4 and NgOX2 (Ng = Kr, Xe; X = F, Cl, Br) have been studied at the B2PLYP-D3(BJ)/ aug-cc-pVTZ (PP) level. Two kinds of aerogen-bonding interactions were observed among the title systems: the σ-hole and the π-hole complexes. The σ-hole aerogen-bonding complex has a binding energy in the range of - 6.29 ~ - 8.17 kcal/mol, which is the most stable. The binding energies of C2H4···NgOX2 increased as X = F < Cl < Br and Ng = KrOX2 < XeOX2 for the σ/π-hole aerogen-bonding complexes. The atoms in molecules (AIM), the non-covalent interaction (NCI) index, and the LMO-EDA energy decomposition analysis were adopted to study the nature of the σ/π-hole aerogen-bonding interaction. The results show that the electrostatic term contributes the most to the total interaction energy for the σ/π-hole aerogen-bonding complexes.

3.
Guang Pu Xue Yu Guang Pu Fen Xi ; 31(11): 3149-53, 2011 Nov.
Article in Zh | MEDLINE | ID: mdl-22242537

ABSTRACT

During the spectral imaging course of interference imaging spectrometers, satellite platform's instability will bring serious impact on the imaging quality. Based on studying the degradation mechanism, a differential dynamic imaging simulation method is proposed here to simulate the process of spectral imaging degradation. And in this method, the mean ratio of doping is put forward, which combines the satellite motion parameters with the impacts on spectral imaging. And the quantitative relationship between them is deduced in detail With environmental resources satellite as an example, the degraded result is simulated, showing that the vibration affects the spectral imaging not only in the spatial resolution but also in spectrum, with the region of rich species having more serious influence. And through the simulation and analysis, the satellite attitudes' stability is requested accurately, below which the impacts of satellite vibration on spectral imaging should be significant and it's necessary to adopt corresponding compensation measures.

4.
Guang Pu Xue Yu Guang Pu Fen Xi ; 31(7): 1762-6, 2011 Jul.
Article in Zh | MEDLINE | ID: mdl-21942019

ABSTRACT

All-reflection Fourier transform imaging spectrometer (ARFTIS) is a novel imaging spectrometer. The specialty is not only high spectrum resolution, but also wide band and non-chromatism. It is good for remote sensing field of wide band imaging. Single spectrum calibration, average calibration and weighted average calibration are three common calibration methods. However, they all are limited. Because they cannot meet the demand on both convenience and high precision. In the present paper, the authors propose a novel model for spectrum calibration. It can work in high precision with single spectrum calibration. At the same time, the method is steady, and the average error is less than 5% with multi-bands calibration. It provides a convenient way for the non-professional calibration situation and outer simply calibration work.

5.
Article in English | MEDLINE | ID: mdl-19062332

ABSTRACT

Eu(3+) (or Tb(3+)) of 3,5-dinitrobenzoic acid and 1,10-phenanthroline ternary rare earth complexes were synthesized and characterized by thermal analysis, infrared spectroscopy, elemental analysis and fluorescence spectroscopy. In this study an organic-inorganic combined device indium tin oxide/poly(N-vinylcar-bazole):RE(3,5-DNBA)(3)Phen:TiO(2)/Al was fabricated. The nano-TiO(2) has been used in the luminescence layer to change the electroluminescence property of RE(3,5-DNBA)(3) Phen (RE=Eu(3+)or Tb(3+)).


Subject(s)
Europium/chemistry , Luminescence , Nanostructures/chemistry , Nitrobenzoates/chemistry , Phenanthrolines/chemistry , Titanium/chemistry , Differential Thermal Analysis , Ligands , Spectrophotometry, Infrared , Thermogravimetry
6.
J Chem Phys ; 129(19): 194902, 2008 Nov 21.
Article in English | MEDLINE | ID: mdl-19026084

ABSTRACT

Noise-induced oscillation (NIO) was investigated in a model of an oil-water membrane oscillator. First, we analyzed an unexcitable region and an excitable region of the system by proposing a critical threshold of NIO appearance and found a linearlike relation between the critical threshold and noise intensity. Then the phenomenon of noise-induced coherence resonance was investigated by calculating the signal-to-noise ratio. Furthermore, it was found that an optimal noise intensity range could most improve the appearance of effective oscillation (EO). The presence of EO regions made the stochastic model show EO at a more extended region than the deterministic description.


Subject(s)
Membranes, Artificial , Noise , Oils/chemistry , Water/chemistry
7.
Article in English | MEDLINE | ID: mdl-17913576

ABSTRACT

The binary complex of Tb(III) with N-phenylanthranilic acid (N-HPA) was synthesized, and the ternary complexes were synthesized by introducing 1,10-phenanthroline (Phen), 2,2'-dipyridyl (Bipy), trioctylphosphine oxide (TPPO) as the second ligand, respectively. These complexes were characterized by infrared spectra, UV spectra and fluorescence spectra. The effect and mechanism of different second ligands on the fluorescent intensity of the terbium N-phenylanthranilic acid complexes was discussed. It showed that all the complexes exhibited ligand-sensitized green emission. The luminescence intensity increased in the sequence of Tb(N-PA)(3)Phen

Subject(s)
Luminescence , Terbium/chemistry , Ligands , Spectrometry, Fluorescence , Spectrophotometry, Infrared , Spectrophotometry, Ultraviolet
8.
Article in English | MEDLINE | ID: mdl-17826310

ABSTRACT

Rare-earth ternary complexes Tb(1-x)Eu(x)(m-NBA)(3)Phen (X=1, 0.25, 0.5, 0.75, 1.0) were synthesized and characterized by IR, DTA-TG, UV, fluorescent spectra and elemental analysis. It was found that luminescence of Eu(3+) complex was enhanced by doped with Tb(3+). It is proved by TG curve that the complexes are stable, ranging from ambient temperature to 360 degrees C in air. The organic-inorganic combined structural device was fabricated, and the electroluminescence intensity of the combined structural device was improved compared with the device of the purely organic components.


Subject(s)
Luminescence , Metals, Rare Earth/chemistry , Sulfides/chemistry , Zinc Compounds/chemistry , Differential Thermal Analysis , Electrochemistry , Elements , Ligands , Spectrometry, Fluorescence , Spectrophotometry, Infrared , Spectrophotometry, Ultraviolet , Thermogravimetry
9.
J Colloid Interface Sci ; 307(1): 94-100, 2007 Mar 01.
Article in English | MEDLINE | ID: mdl-17188288

ABSTRACT

A novel cetyltrimethyl ammonium silver bromide (CTASB) complex has been prepared simply through the reaction of silver nitrate with cetyltrimethyl ammonium bromide (CTAB) in aqueous solution at room temperature by controlling the concentration of CTAB and the molar ratio of CTAB to silver nitrate in the reaction solution, in which halogen in CTAB is used as surfactant counterion. The structure and thermal behavior of cetyltrimethyl ammonium silver bromide have been investigated by using X-ray diffraction (XRD), infrared spectroscopy (IR), X-ray photoelectron spectroscopy (XPS), UV/vis spectroscopy, thermal analysis (TG-DTA), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). The results show that the complex possesses a metastable layered structure. Upon heating the CTASB aqueous dispersion to above 80 degrees C, the structure change of the complex took place and CTAB-capped nanosized silver bromide particles further formed.

10.
Article in English | MEDLINE | ID: mdl-17329150

ABSTRACT

Rare-earth ternary complexes Eu(X)Y(1-X)(TTA)3Dipy {X=0, 0.1, 0.25, 0.5, 0.75, 0.9, 1.0, using thenoyltrifluoroacetone (TTA) as ligand and 2,2'-dipyridyl (Dipy) as synergic agent} were synthesized. Characterization with X-ray diffraction (XRD), IR and elemental analysis had also been carried out. The photophysical properties of these complexes were studied in detail with ultraviolet absorption spectra and fluorescent spectra. It is found that the enhanced luminescence of Eu(3+) ions by Y(3+) ions occurs in ternary complexes. And we monitored the spectra of Eu(X)Y(1-X)(TTA)3Dipy (PVK:Eu/BCP/AlQ/Al) at the different rate (rpm). The results showed that the Y(3+) ion acts as an energy transfer bridge that helps energy transfer from PVK to Eu(3+).


Subject(s)
2,2'-Dipyridyl/chemistry , Europium/chemistry , Organometallic Compounds/chemistry , Thenoyltrifluoroacetone/chemistry , Yttrium/chemistry , Electrochemistry , Ligands , Luminescence , Spectrometry, Fluorescence , Spectrophotometry, Infrared , Spectrophotometry, Ultraviolet , X-Ray Diffraction
11.
Guang Pu Xue Yu Guang Pu Fen Xi ; 27(5): 850-3, 2007 May.
Article in Zh | MEDLINE | ID: mdl-17655087

ABSTRACT

The new complex Tb0.5 Eu0.5 (TTA)3Dipy was synthesized. By doping polymer PVK with Tb0.5 Eu0.5 (TTA)3Dipy, the EL device was fabricated with the structure of ITO/PVK: Tb0.5 Eu0.5 (TTA)3Dipy/PBD/Al using PVK: Tb0.5 Eu0.5 (TTA)3Dipy as the emitting layer. Compared with the blend PVK: Eu(TTA)3, the Tb3+ acts as an energy transfer bridge, which enhances the energy transfer efficiency between PVK and Tb0.5 Eu0.5 (TTA)3Dipy. As a result, the emission of Eu3+ is enhanced with the quenching of the emission of PVK. The process of energy transfer was studied.


Subject(s)
Organometallic Compounds/analysis , Spectrometry, Fluorescence/methods , Energy Transfer , Europium , Molecular Structure , Terbium
12.
J Environ Sci (China) ; 17(2): 350-2, 2005.
Article in English | MEDLINE | ID: mdl-16295920

ABSTRACT

A series of TiO2-MoO3 nano-composite photocatalysts were prepared by supercritical fluid dry method (SCFD) and an impregnation technique with TiCl4 and (NH4)6Mo7O24.4H2O as the starting materials. The catalysts were characterized by the means of XRD, TEM and UV-Vis. Methyl orange was used as model compound for the evaluation of their catalytic activities. The results indicated that the photo-catalyst prepared by SCFD had the advantages of small size (12.84 nm), narrow distribution and good dispersivity. The presence of small amount of Mo in composite catalyst gives rise to the red shift of its absorbance wavelength, decrease of its energy gap and increase of the utility of visible light. Furthermore, higher surface acidity of the photo-catalyst was obtained as the result of the addition of MoO3. Compared with pure TiO2, the catalytic activity of the TiO2-MoO3 nano-composite photo-catalyst was improved significantly. As the doping concentration of the composite catalysts was controlled at 0.6% (molar percentage), 100% degradation of methyl orange was achieved with in 1.2 h irradiation time.


Subject(s)
Environmental Pollution/prevention & control , Molybdenum/chemistry , Nanostructures/chemistry , Nanotechnology/methods , Titanium/chemistry , Azo Compounds/chemistry , Catalysis , Kinetics , Microscopy, Electron, Transmission , Nanostructures/ultrastructure , Nanotechnology/instrumentation , Photolysis , Spectrophotometry, Ultraviolet
13.
J Chem Theory Comput ; 3(1): 95-102, 2007 Jan.
Article in English | MEDLINE | ID: mdl-26627156

ABSTRACT

The interactions of the first-row hydrides (HF, H2O, and NH3) with ClF have been investigated by performing calculations at the second-order perturbation theory based on the Møller-Plesset partition of the Hamiltonian with the aug-cc-pVTZ basis set. The geometries and vibrational frequencies in the present study were obtained by carrying out explicit counterpoise-corrected optimization. In order to understand that the Cl-X-type (X = F, O, and N) structure is more stable than the corresponding hydrogen-bonded structure in these complexes, the electronic properties were also investigated. Furthermore, the symmetry-adapted perturbation theory calculations were performed to gain more insight into the nature of the hydrogen-bond and Cl-X-type interactions. The analysis of the interaction energy components indicates that, in contrast to the hydrogen-bonded complexes, the inductive and dispersive interaction is the most important term in the Cl-X-type complexes, as we progress from HF to NH3.

14.
J Chem Phys ; 127(17): 175102, 2007 Nov 07.
Article in English | MEDLINE | ID: mdl-17994852

ABSTRACT

The nature of interactions of furan with various hydrides (Y) (Y=HF,HCl,H2O,H2S,NH3,PH3) is investigated using ab initio calculations. The contribution of attractive (electrostatic, inductive, and dispersive) and repulsive (exchange) components to the interactions energy is analyzed. HF, H2O, and NH3 favor sigma o-type H bonding, while HCl, H2S, and PH3 favor pi-type H bonding. Interaction energy decomposition reveals that sigma o-type complexes interactions are predominantly electrostatic in nature, while the dispersion and electrostatic interactions dominate the pi-type complexes.

15.
J Chem Phys ; 126(13): 134301, 2007 Apr 07.
Article in English | MEDLINE | ID: mdl-17430026

ABSTRACT

Equilibrium geometries, interaction energies, atomic charge, and charge transfer for the intermolecular interactions between furan and dihalogen molecules XY(X; Y=F,Cl,Br) were studied at the MP2aug-cc-pVDZ level. Three types of geometry are observed in these interactions: the pi-type geometry (I), in which the XY lies above the furan ring and almost perpendicularly to the C4-C5 bond of furan; the sigma-type geometry (II), where the X atom is pointed toward the nonbonding electron pair (n pair) of oxygen atom in furan; and the chi-type geometry (III), describing a blueshift hydrogen bond formed between the hydrogen atom of furan and dihalogen molecules XY. The calculated interaction energies show that the pi-type structures are more stable than the corresponding sigma-type and chi-type structures. To study the nature of the intermolecular interactions, an energy decomposition analysis was carried out and the results indicate that both the pi-type and sigma-type interactions are dominantly inductive energy in nature, while dispersion energy governs the chi-type interactions.

16.
J Chem Phys ; 126(14): 144301, 2007 Apr 14.
Article in English | MEDLINE | ID: mdl-17444706

ABSTRACT

Using ab initio calculations, the authors' predicted for the first time that the halogen-bonded complex FBrdelta+...delta+BrF and hydrogen-bonded complex FBrdelta+...delta+HF formed by the interactions between two positively charged atoms of different polar molecules can be stable in gas phase. It shows that halogen bond or hydrogen bond not only exists between oppositely charged atoms but also between like-charged atoms. That the attraction arising from the special halogen bond or hydrogen bond can exceed the electrostatic repulsion between two contact positively charged atoms stabilizes the complex. Of course, from the point of view of physics they can consider the interactions in FBrdelta+...delta+BrF and FBrdelta+...delta+HF as mainly the sum of the long range molecular interactions, namely, electrostatic, induction, and dispersion with some short-range repulsion. They found that the intermolecular electron correlation contribution representing dispersion interaction plays a crucial role in the stabilities of seemingly repulsive complexes FBrdelta+...delta+BrF and FBrdelta+...delta+HF.


Subject(s)
Halogens/chemistry , Models, Chemical , Models, Molecular , Binding Sites , Computer Simulation , Energy Transfer , Hydrogen Bonding , Hydrophobic and Hydrophilic Interactions , Static Electricity
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