PubMed Health⌕ Search

Biomedical subjects

Qing Peng

Publications and source records attributed to Qing Peng.

At least 19 recordsLinked to original sources
PubMed2026

Screening of core targets for Di(2-ethylhexyl) Phthalate-related gastric cancer based on machine learning, molecular docking, and SHAP analysis.

PURPOSE: Given the existing uncertainties regarding the link between Di(2-ethylhexyl) phthalate (DEHP) exposure and gastric cancer (GC) progression, this study aimed to clarify their association, identify the toxic targets of DEHP, and elucidate the underlying molecular mechanisms. METHODS: Multiple integrated approaches were employed, including Gene Expression Omnibus (GEO) data analysis, network toxicology, molecular docking, and machine learning. STRING and Cytoscape tools were utilized to identify key targets, while Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were performed to explore the functional enrichment of intersecting targets. Machine learning and SHAP analysis were applied to screen core targets in GC. Molecular docking was performed to evaluate the binding affinity of DEHP toward core targets, and 200 ns molecular dynamics simulations were further conducted for representative complexes to validate their dynamic stability. RESULTS: A total of 18 key targets were identified using STRING and Cytoscape. GO and KEGG enrichment analyses demonstrated that these intersecting targets were primarily enriched in the extracellular region, as well as the Calcium signaling pathway and cAMP signaling pathway. Through machine learning analyses, 7 key genes (ADRB2, ESRRG, GRIA4, IL13RA2, NR3C2, PLA2G1B, and SULT2A1) were identified as core targets in GC through machine learning analyses. Molecular docking simulations revealed strong binding specificity between DEHP and the target proteins. Among them, NR3C2 and ADRB2 exhibited relatively high predictive importance in the machine learning models. DEHP showed favorable binding affinity toward these core targets, and molecular dynamics simulations further confirmed that ADRB2-DEHP and NR3C2-DEHP complexes maintained stable conformations throughout the simulation. CONCLUSIONS: Our findings identified GC associated genes that were computationally predicted as potential targets of DEHP. These results indicated structural compatibility between DEHP and its target proteins but did not prove that DEHP exposure accounts for the gene expression changes in GC.

Molecular Docking Simulation↗
PubMed2006

Hydrothermal synthesis of rare-earth fluoride nanocrystals.

In this paper, a hydrothermal synthetic route has been developed to prepare a class of rare-earth fluoride nanocrystals, which have shown gradual changes in growth modes with decreasing ionic radii and may serve as a model system for studying the underlying principle in the controlled growth of rare-earth nanocrystals. Furthermore, we demonstrate the functionalization of these nanocrystals by means of doping, which have shown visible-to-the-naked-eye green up-conversion emissions and may find application in biological labeling fields.

Fluorides↗
PubMed2006

Synthesis and characterization of sulfide and selenide colloidal semiconductor nanocrystals.

In this paper, we demonstrate the synthesis of sulfide and selenide nanocrystals in a water-ethanol mixed solution system. This synthetic way was based on the direct reactions between metal ions and S(2-)/Se. Linoleic acid was adopted to protect the nanocrystals from agglomeration. Without involving extreme experimental conditions, this less toxic synthetic route can be expected to bring more opportunities to nanocrystal-related research and application fields.

Journal Article↗
PubMed2006

Synthesis of CdSe, ZnSe, and ZnxCd1-xSe nanocrystals and their silica sheathed core/shell structures.

Uniform ZnxCd1-xSe nanocrystals have been prepared at the artificially designed water-oil interface using Na2SeO3, Cd(NO3)2, and Zn(NO3)2 as precursors. The chemical composition and band gap of the ZnxCd1-xSe nanocrystals can be adjusted via different combinations of source material. The coating of a SiO2 shell could transform the hydrophobic particles into hydrophilic particles. An advantage of this method is that a water phase could be added to the oleic acid (OLEA) synthesis system, which could be extended to make the synthesis of various nanocrystals more simple and flexible.

Journal Article↗
PubMed2006

Near monodisperse TiO2 nanoparticles and nanorods.

Highly crystalline, near monodisperse TiO2 nanoparticles, nanorods and their metal-ion-doped (Sn4+, Fe3+, Co2+, and Ni2+, etc.) derivatives have been prepared by well-controlled solvothermal reactions. Through adjusting the reaction parameters, such as reaction temperature, duration, and concentration of the reactants, the size, shape, and dispersibility of the products can be controlled. A possible reaction mechanism can be proposed based on experimental evidence.

Journal Article↗
PubMed2005

Controlled hydrothermal synthesis and structural characterization of a nickel selenide series.

A series of nickel selenides (NiSe2 microcrystals, Ni(1-x)Se and Ni3Se2 microspheres) has been successfully synthesized through a convenient, low-temperature hydrothermal method. A good nucleation and growth environment has been created by forming a uniform and transparent solution reaction system. The compositions (including the x value of Ni(1-x)Se), phase structures, as well as the morphologies of nickel selenides, can be controlled by adjusting the Ni/Se ratio of the raw materials, the pH, the reaction temperatures and times, and so forth. The newly produced Se microspheres in the system have been used as both reactant and in situ template to the Ni(1-x)Se microspheres. It is found that Ni(1-x)Se microspheres act as the intermediate precursor during the formation of Ni3Se2 microspheres. Under certain conditions, hexagonal NiSe microspheres can be converted into rhombohedral NiSe nanowires in solution. The formation mechanisms of a series of nickel selenides has been investigated in detail by means of X-ray diffraction (XRD) and scanning electron microscopy (SEM) analyses. This work has provided a general, simple, and effective method to control the composition, phase structure, and morphology of metal selenides in aqueous solution, which will be important for inorganic synthesis methodology and further applications of selenides.

Journal Article↗
PubMed2005

Chromate nanorods/nanobelts: general synthesis, characterization, and properties.

A general synthesis route to a family of single-crystal chromate nanorods/nanobelts has been established. The effects of pH and surfactant on phase and morphology of these microcrystalline materials have been investigated. The physical properties of the as-synthesized chromate nanocrystals such as dielectric, electrochemical, UV-vis absorbance, and photoluminescent properties have also been studied. The present general synthesis of various low-dimensional chromate nanomaterials provides useful information on the possible synthesis of other microcrystalline transition metal oxysalts.

Journal Article↗
PubMed2005

Controlled hydrothermal synthesis of bismuth oxyhalide nanobelts and nanotubes.

Ternary bismuth oxyhalide crystalline nanobelts (such as Bi24O31Br10, Bi3O4Br, Bi12O17Br2, BiOCl, and Bi24O31Cl10) and nanotubes (such as Bi24O31Br10) have been synthesized by using convenient hydrothermal methods. The composition and morphologies of the bismuth oxyhalides could be controlled by adjusting some growth parameters, including reaction pH, time, and temperature. All the nanostructures were characterized by using various methods including X-ray diffraction, transmission electron microscopy, high-resolution TEM, electron diffraction, and energy-dispersive X-ray analysis. The possible reaction mechanism and growth of the crystals are discussed based on the experimental results.

Bismuth↗
PubMed2005

Synthesis and characterization of Mn2P2S6 single-crystal nanorods and nanotubes.

Mn2P2S6 single-crystal nanorods with diameters 20-40 nm and lengths up to 1 microm and nanotubes with diameters 40-50 nm and lengths ranging between 110 and 170 nm have been prepared through a low-temperature solvothermal method. They have been characterized by X-ray diffraction, transmission electron microscopy (TEM), high-resolution (HR) TEM, electron diffraction, energy-dispersive spectrometry analysis, X-ray photoelectron spectroscopy, and Raman spectroscopy.

Journal Article↗
PubMed2005

A general strategy for nanocrystal synthesis.

New strategies for materials fabrication are of fundamental importance in the advancement of science and technology. Organometallic and other organic solution phase synthetic routes have enabled the synthesis of functional inorganic quantum dots or nanocrystals. These nanomaterials form the building blocks for new bottom-up approaches to materials assembly for a range of uses; such materials also receive attention because of their intrinsic size-dependent properties and resulting applications. Here we report a unified approach to the synthesis of a large variety of nanocrystals with different chemistries and properties and with low dispersity; these include noble metal, magnetic/dielectric, semiconducting, rare-earth fluorescent, biomedical, organic optoelectronic semiconducting and conducting polymer nanoparticles. This strategy is based on a general phase transfer and separation mechanism occurring at the interfaces of the liquid, solid and solution phases present during the synthesis. We believe our methodology provides a simple and convenient route to a variety of building blocks for assembling materials with novel structure and function in nanotechnology.

Journal Article↗
PubMed2005

Crystal structures, anisotropic growth, and optical properties: controlled synthesis of lanthanide orthophosphate one-dimensional nanomaterials.

The fundamental understanding of the relationship between crystal structure and the dynamic processes of anisotropic growth on the nanoscale, and exploration of the key factors governing the evolution of physical properties in functional nanomaterials, have become two of the most urgent and challenging issues in the fabrication and exploitation of functional nanomaterials with designed properties and the development of nanoscale devices. Herein, we show how structural and kinetic factors govern the tendency for anisotropic growth of such materials under hydrothermal conditions, and how the crystal structure and morphology influence the optical properties of Ln3+-doped nanocrystals. The synthesis of phase-pure and single-crystalline monoclinic, hexagonal, and tetragonal one-dimensional LnPO4 nanostructures of different aspect ratios by means of kinetically controlled hydrothermal growth processes is demonstrated. It is shown that the tendency for anisotropic growth under hydrothermal conditions can be enhanced simply by modifying the chemical potentials of species in the reaction solution through the use of carefully selected chelating ligands. A systematic study of the photoluminescence of various Eu3+-doped lanthanide phosphates has revealed that the optical properties of these nanophosphors are strongly dependent on their crystal structures and morphologies.

Journal Article↗
PubMed2005

Orthogonal PbS nanowire arrays and networks and their Raman scattering behavior.

Three-dimensional, orthogonal lead sulfide (PbS) nanowire arrays and networks have been prepared by using a simple, atmospheric pressure chemical vapor deposition (APCVD) method. These uniform nanowires (average diameter 30 nm) grow epitaxially from the surface of the initial PbS crystal seeds and form orthogonal arrays and networks in space. The growth mechanism has been explored, and the process was classified as homogeneous, epitaxial growth in the 200 directions. Furthermore, Raman spectra of PbS nanowires are reported here, and their characteristic Raman peak (190 cm(-1), no shoulder) could be used as a unique probe for the study of PbS nanomaterials.

Journal Article↗
PubMed2004

Synthesis and characterization of bismuth single-crystalline nanowires and nanospheres.

A facile solution-phase process has been demonstrated for the selective preparation of single-crystalline bismuth nanowires and nanospheres by reducing sodium bismuthate with ethylene glycol in the presence of poly(vinyl pyrrolidone) (PVP) or acetone. Bismuth nanobelts and Bi/Bi(2)O(3) nanocables could be also obtained by changing some reaction parameters. Various techniques such as XRD, EDXA, SEM, TEM, HRTEM, and FT-IR have been used to investigate the physical characteristics of these low-dimensional bismuth nanostructures.

Journal Article↗
PubMed2003

Synthesis of uniform CoTe and NiTe semiconductor nanocluster wires through a novel coreduction method.

A novel coreduction method was developed to synthesize uniform one-dimensional CoTe and NiTe nanocluster wires. In the synthesis, soluble Na(2)TeO(3) was used to supply a highly reactive Te source and N(2)H(4).H(2)O was used both as reducing agent and as complexing agent. The as-prepared samples were characterized by XRD, TEM, and HRTEM. The probable formation mechanism of the nanowires is discussed.

Journal Article↗