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1.
J Phys Condens Matter ; 36(30)2024 May 03.
Article in English | MEDLINE | ID: mdl-38653326

ABSTRACT

Monolayer semiconductors with unique mechanical responses are promising candidates for novel electromechanical applications. Here, through first-principles calculations, we discover that the monolayerß-TeO2, a high-mobilityp-type and environmentally stable 2D semiconductor, exhibits an unusual out-of-plane negative Poisson's ratio (NPR) when a uniaxial strain is applied along the zigzag direction. The NPR originates from the unique six-sublayer puckered structure and hinge-like Te-O bonds in the 2Dß-TeO2. We further propose that the sign of the Raman frequency change under uniaxial tensile strain could assist in determining the lattice orientation of monolayerß-TeO2, which facilitates the experimental study of the NPR. Our results is expected to motivate further experimental and theoretical studies of the rich physical and mechanical properties of monolayerß-TeO2.

2.
World J Gastrointest Surg ; 15(11): 2525-2536, 2023 Nov 27.
Article in English | MEDLINE | ID: mdl-38111763

ABSTRACT

BACKGROUND: Few studies have simultaneously compared the predictive value of various frailty assessment tools for outcome measures in patients undergoing gastrointestinal cancer surgery. Therefore, it is difficult to determine which assessment tool is most relevant to the prognosis of this population. AIM: To investigate the predictive value of three frailty assessment tools for patient prognosis in patients undergoing gastrointestinal cancer surgery. METHODS: This single-centre, observational, prospective cohort study was conducted at the Affiliated Lianyungang Hospital of Xuzhou Medical University from August 2021 to July 2022. A total of 229 patients aged ≥ 18 years who underwent surgery for gastrointestinal cancer were included in this study. We collected baseline data on the participants and administered three scales to assess frailty: The comprehensive geriatric assessment (CGA), Fried phenotype and FRAIL scale. The outcome measures were the postoperative severe complications and increased hospital costs. RESULTS: The prevalence of frailty when assessed with the CGA was 65.9%, 47.6% when assessed with the Fried phenotype, and 34.9% when assessed with the FRAIL scale. Using the CGA as a reference, kappa coefficients were 0.398 for the Fried phenotype and 0.291 for the FRAIL scale (both P < 0.001). Postoperative severe complications and increased hospital costs were observed in 29 (12.7%) and 57 (24.9%) patients, respectively. Multivariate logistic analysis confirmed that the CGA was independently associated with increased hospital costs (odds ratio = 2.298, 95% confidence interval: 1.044-5.057; P = 0.039). None of the frailty assessment tools were associated with postoperative severe complications. CONCLUSION: The CGA was an independent predictor of increased hospital costs in patients undergoing surgery for gastrointestinal cancer.

3.
Phys Chem Chem Phys ; 25(46): 31747-31753, 2023 Nov 29.
Article in English | MEDLINE | ID: mdl-37964736

ABSTRACT

Intrinsic one-dimensional (1D) helix chain materials are extremely rare in inorganic chemistry due to their novel structural features and complex syntheses. Herein, we report a class of inborn 1D helix chains, namely 1D SbSX (X = Cl, Br, I), that can exist stably. Through ab initio calculations, we demonstrate that the formation of this helical feature is facilitated by the lone pairs in antimony atoms. Owing to the different chemical bonds induced by the lone pairs, a phase transition between different helix chain phases can occur by applying extra elongation strain. More importantly, 1D SbSX helix chains possess superior flexibility. Under large elongation strains, the elastic energy is stored via bond angle redistributions, while the average bond lengths can remain invariant. Our work not only enriches the family of intrinsic 1D helical materials, but also provides a novel avenue for the diversification of low-dimensional phase change and flexible materials.

4.
Nanotechnology ; 34(50)2023 Oct 06.
Article in English | MEDLINE | ID: mdl-37703834

ABSTRACT

ß-FeOOH nanorods were prepared via the urea hydrolysis process with the average length of 289.1 nm and average diameter of 61.2 nm, while magneticα-Fe2O3/Fe3O4heterostructure nanorods were prepared via the urea calcination process withß-FeOOH nanorods as precursor, and the optimum conditions were the calcination temperature of 400 °C, the calcination time of 2 h, theß-FeOOH/urea mass ratio of 1:6. The average length, diameter, and the saturation magnetization of the heterostructure nanorods prepared under the optimum conditions were 328.8 nm, 63.4 nm and 42 emu·g-1, respectively. The Prussian blue test demonstrated that the heterostructure nanorods could be taken up by HepG2 cells, and cytotoxicity tests proved that the heterostructure nanorods had no significant effect on the viabilities of LO2 and HepG2 cells within 72 h in the range of 100-1600µg·ml-1. Therefore, magneticα-Fe2O3/Fe3O4heterostructure nanorods had better biocompatibility with LO2 and HepG2 cells.

5.
Materials (Basel) ; 16(7)2023 Mar 28.
Article in English | MEDLINE | ID: mdl-37048996

ABSTRACT

It has been found that the mechanic-electric response of cement-based piezoelectric composites under impact loading is nonlinear. Herein, we prepared a 2-2 cement-based piezoelectric composite material using cutting, pouring, and re-cutting. Then, we obtained the stress-strain and stress-electric displacement curves for this piezoelectric composite under impact loading using a modified split Hopkinson pressure bar (SHPB) experimental apparatus and an additional electrical output measurement system. Based on the micromechanics of the composite materials, we assumed that damage occurred only in the cement paste. The mechanical response relationship of the piezoelectric composite was calculated as the product of the viscoelastic constitutive relationship of the cement paste and a constant, where the constant was determined based on the reinforcement properties of the mechanical response of the piezoelectric composite. Using a modified nonlinear viscoelastic Zhu-Wang-Tang (ZWT) model, we characterized the stress-strain curves of the piezoelectric composite with different strain rates. The dynamic sensitivity and stress threshold of the linear response of the samples were calibrated and fitted. Thus, a mechanic-electric response equation was established for the 2-2 type cement-based piezoelectric composite considering the strain rate effects.

6.
Mikrochim Acta ; 190(5): 189, 2023 04 21.
Article in English | MEDLINE | ID: mdl-37083854

ABSTRACT

The CYP2C19*2 gene carriers and non-carriers are closely related to the dosage of clopidogrel. To correctly guide the use of clopidogrel and promote individualized therapy, an ultra-sensitive electrochemical biosensor was developed for the detection of CYP2C19*2 gene. The heterogeneous α-Fe2O3/Fe3O4 nanosheets were prepared via the hydrothermal-calcination process, and the preparation parameters were optimized. The average diameter and thickness of the nanosheets were approximately 150 nm and 53 nm, respectively; and the saturation magnetization was 80.2 emu/g. The α-Fe2O3/Fe3O4@Au nanosheets were prepared by sodium borohydride reduction method, and self-assembled to the electrode surface with magnetic field. Ultra-sensitive detection of CYP2C19*2 gene was realized through the recognition ability of strong single base mismatching of peptide nucleic acid and signal amplification effect of magnetic α-Fe2O3/Fe3O4@Au nanosheets. Under optimal detection conditions, the current had a good linear correlation with the negative logarithm of CYP2C19*2 gene concentration in the range 1 pM-1 nM, and the detection limit was 0.64 pM (S/N = 3). Meanwhile, the electrochemical signals of target DNA and incomplete complementary DNA were detected. The constructed biosensor exhibited good selectivity, reproducibility, and stability, providing a promising strategy for the detection of other gene mutations by electrochemical biosensors.


Subject(s)
Peptide Nucleic Acids , Cytochrome P-450 CYP2C19 , Clopidogrel , Reproducibility of Results , DNA
7.
Adv Mater ; 35(22): e2300450, 2023 Jun.
Article in English | MEDLINE | ID: mdl-36868783

ABSTRACT

Phase engineering by strain in 2D semiconductors is of great importance for a variety of applications. Here, a study of the strain-induced ferroelectric (FE) transition in bismuth oxyselenide (Bi2 O2 Se) films, a high-performance (HP) semiconductor for next-generation electronics, is presented. Bi2 O2 Se is not FE at ambient pressure. At a loading force of ≳400 nN, the piezoelectric force responses exhibit butterfly loops in magnitude and 180° phase switching. By carefully ruling out extrinsic factors, these features are attributed to a transition to the FE phase. The transition is further supported by the appearance of a sharp peak in optical second-harmonic generation under uniaxial strain. In general, solids with paraelectrics at ambient pressure and FE under strain are rare. The FE transition is discussed using first-principles calculations and theoretical simulations. The switching of FE polarization acts as a knob for Schottky barrier engineering at contacts and serves as the basis for a memristor with a huge on/off current ratio of 106 . This work adds a new degree of freedom to HP electronic/optoelectronic semiconductors, and the integration of FE and HP semiconductivity paves the way for many exciting functionalities, including HP neuromorphic computing and bulk piezophotovoltaics.

8.
Drug Deliv ; 30(1): 64-82, 2023 Dec.
Article in English | MEDLINE | ID: mdl-36474448

ABSTRACT

Magnetic Fe3O4 nanoparticles were prepared via a simple hydrothermal method and utilized to load paclitaxel. The average particle size of Fe3O4 nanoparticles was found to be 20.2 ± 3.0 nm, and the calculated saturation magnetization reached 129.38 emu/g, verifying superparamagnetism of nanomaterials. The specific surface area and pore volume were 84.756 m2/g and 0.265 cm3/g, respectively. Subsequently, Fe3O4@mSiO2 nanoparticles were successfully fabricated using the Fe3O4 nanoparticles as precursors with an average size of 27.81 nm. The relevant saturation magnetization, zeta potential, and specific surface area of Fe3O4@mSiO2-NH2-FA were respectively 76.3 emu/g, -14.1 mV, and 324.410 m2/g. The pore volume and average adsorption pore size were 0.369 cm3/g and 4.548 nm, respectively. Compared to free paclitaxel, the solubility and stability of nanoparticles loaded with paclitaxel were improved. The drug loading efficiency and drug load of the nanoformulation were 44.26 and 11.38%, respectively. The Fe3O4@mSiO2-NH2-FA nanocomposites were easy to construct with excellent active targeting performance, pH sensitivity, and sustained-release effect. The nanoformulation also showed good biocompatibility, where the cell viability remained at 73.8% when the concentration reached 1200 µg/mL. The nanoformulation induced cell death through apoptosis, as confirmed by AO/EB staining and flow cytometry. Western blotting results suggested that the nanoformulation could induce iron death by inhibiting Glutathione Peroxidase 4 (GPX4) activity or decreasing Ferritin Heavy Chain 1 (FTH1) expression. Subsequently, the expression of HIF-1α was upregulated owing to the accumulation of reactive oxygen species (ROS), thus affecting the expression of apoptosis-related proteins regulated by p53, inducing cell apoptosis.


Subject(s)
Magnetic Phenomena , Paclitaxel , Humans , MCF-7 Cells , Paclitaxel/pharmacology
9.
Bioelectrochemistry ; 148: 108255, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36096074

ABSTRACT

A label-free electrochemical aptasensor based on magnetic α-Fe2O3/Fe3O4 heterogeneous hollow nanorods was developed for the detection of cancer antigen 125 (CA125). Magnetic α-Fe2O3/Fe3O4 heterogeneous hollow nanorods were successfully prepared by the hydrolysis-calcination method, functionalized with polyethyleneimine (PEI), and modified with HAuCl4 to form magnetic α-Fe2O3/Fe3O4-Au nanocomposites with a layer of 5 nm gold nanoparticles (Au NPs) on the surface. The magnetic α-Fe2O3/Fe3O4-Au nanocomposites were used to fix the DNA-aptamer probe to amplify the current signal. The intensity of the current signal was proportional to the concentration of CA125, indicating that the sensor was a turn-on sensor. The linear range of the electrochemical aptasensor was 5-125 U/mL (R2 = 0.9975), and the limit of detection (LOD) was 2.99 U/mL. The electrochemical aptasensor exhibited favorable specificity, reproducibility, and stability. The analytical performance of the aptasensor in real serum samples was also investigated.


Subject(s)
Aptamers, Nucleotide , Biosensing Techniques , Metal Nanoparticles , Nanotubes, Carbon , Neoplasms , Biosensing Techniques/methods , CA-125 Antigen , DNA , Electrochemical Techniques/methods , Gold , Humans , Limit of Detection , Magnetic Phenomena , Polyethyleneimine , Reproducibility of Results
10.
Biomater Adv ; 136: 212783, 2022 May.
Article in English | MEDLINE | ID: mdl-35929317

ABSTRACT

In this work, the magnetic α-Fe2O3/Fe3O4 heterogeneous nanotubes were successfully prepared by solvent hydrothermal-controlled calcination method. The effects of additive concentration, hydrothermal temperature and time on morphology of products were investigated. The α-Fe2O3/Fe3O4 nanotubes with a saturation magnetization of 50 emu/g were prepared calcinated at 600 °C for 4 h using 0.8 g of glucose. Their average length, the outer and inner diameters were around 240 nm, 178 nm and 145 nm, respectively. The α-Fe2O3/Fe3O4 heterogeneous nanotubes coated with water-soluble liposome were applied for targeted delivery of curcumin. The release of curcumin inside the hollow structure of the nanocomposites could be triggered and effectively sustained represented a process of slow release. The encapsulation efficiency of curcumin in the α-Fe2O3/Fe3O4-CUR@LIP nanocomposites reached 82.1 ± 0.9%. MTT assays demonstrated that blank carriers had excellent biocompatibility and application of magnetic field significantly elevated the cytotoxicity of α-Fe2O3/Fe3O4-CUR@LIP nanocomposites on MCF-7 cell. Electrochemical experiment and Prussian blue staining indicated that the α-Fe2O3/Fe3O4@LIP nanocomposites could aggregate in cells to promote the internalization of curcumin. Magnetic α-Fe2O3/Fe3O4-CUR@LIP nanocomposites and curcumin enhanced the expression of reactive oxygen species in MCF-7 cells and induced apoptosis by fluorescence detection. Flow cytometry and western blot verified that the α-Fe2O3/Fe3O4@LIP nanocomposites under magnetic field enhanced cells late-apoptosis by adjusting the expression of apoptosis-related proteins.


Subject(s)
Curcumin , Nanotubes , Apoptosis , Curcumin/pharmacology , Humans , MCF-7 Cells , Magnetic Phenomena
11.
J Am Chem Soc ; 144(10): 4541-4549, 2022 Mar 16.
Article in English | MEDLINE | ID: mdl-35235335

ABSTRACT

High-mobility layered semiconductors have the potential to enable the next-generation electronics and computing. This paper demonstrates that the ultrahigh electron mobility observed in the layered semiconductor Bi2O2Se originates from an incipient ferroelectric transition that endows the material with a robust protection against mobility degradation by Coulomb scattering. Based on first-principles calculations of electron-phonon interaction and ionized impurity scattering, it is shown that the electron mobility of Bi2O2Se can reach 104 to 106 cm2 V-1 s-1 over a wide range of realistic doping concentrations. Furthermore, a small elastic strain of 1.7% can drive the material toward a unique interlayer ferroelectric transition, resulting in a large increase in the dielectric permittivity and a giant enhancement of the low-temperature electron mobility by more than an order of magnitude. These results establish a new route to realize high-mobility layered semiconductors via phase and dielectric engineering.

12.
ACS Appl Mater Interfaces ; 14(3): 4230-4241, 2022 Jan 26.
Article in English | MEDLINE | ID: mdl-35025197

ABSTRACT

On account of the high theoretical capacity and preferable electrochemical reversibility, tin selenides have emerged as potential anode materials in the field of sodium ion batteries (SIBs). Unfortunately, the large volume changes, low electrical conductivity, and shuttling effect of polyselenides have impeded their real application. In this work, we present a spatially confined reaction approach for controllable fabrication of SnSe spheres, which are embedded in polydopamine (PDA)-derived N, Se dual-doped carbon networks (SnSe@NSC) through a one-step carbonization and selenization method. The NSC shell can not only buffer the volume changes during the cycling but also ensure strong coupling interaction between the SnSe core and carbon shell through Sn-C bonds, leading to excellent conductivity and structural integrity of the composite. Meanwhile, DFT theory calculations confirm that N, Se codoping in the carbon shell can endow the composite with enhanced adsorption energy and accelerated transfer ability of Na+. Consequently, the SnSe@NSC anode exhibits a high discharge capacity of 302.6 mA h g-1 over 500 cycles at 1 A g-1 and a competitive rate capability of 285.3 mA h g-1 at 10 A g-1. Additionally, a sodium ion full battery is assembled by coupling the SnSe@NSC anode with the cathode of Na3V2(PO4)3 and verified with good cycling durability (190 mA h g-1 at 1 A g-1 over 500 cycles) and high energy density (204.3 W h kg-1). Our scalable and facile design of heterostructured SnSe@NSC provides a new avenue to develop novel advanced anode materials for SIBs.

13.
Biomed Pharmacother ; 143: 112181, 2021 Nov.
Article in English | MEDLINE | ID: mdl-34649337

ABSTRACT

Jiangzhi Granule is a commonly used traditional Chinese medicine for treating non-alcoholic fatty liver disease. However, its key ingredients and underlying mechanisms for attenuating nonalcoholic steatohepatitis (NASH) remain unclear. To address this issue, UPLC-TOF-MS based chemical profiling, network pharmacology and animal experimental validation were employed. First, a total of 56 main ingredients of Jiangzhi Granule and 38 ingredients in the blood and liver (after oral administration) were identified. Then, 170 potential targets of the absorbed ingredients and 50 targets of NASH were identified, and 10 overlapped genes were identified as candidate targets of Jiangzhi Granule for NASH treatment. A Jiangzhi Granule-ingredients-targets-disease network was constructed using Cytoscape software, which included eight main ingredients (such as emodin, resveratrol and quercetin) and 10 candidate targets (such as TNF, IL6 and CCL2). Functional enrichment indicated that the candidate targets were enriched in multiple pathways (such as the TNF signaling pathway). Furthermore, a NASH mice model was constructed and intervened with Jiangzhi Granule. The results revealed that Jiangzhi Granule could ameliorate NASH characteristics, such as histopathological changes and liver cholesterol level. Meanwhile, Jiangzhi Granule significantly decreased the mRNA and protein expression of TNFα in NASH mice liver, suppressed NFκB activation, and inhibited the expression of macrophage activation marker F4/80 and M1-type polarization marker CD11b/CD11c. ELISA assay indicated that Jiangzhi Granule reduced pro-inflammatory cytokines (including TNFα, IL-1ß and IL-6) in the liver. Collectively, our results suggested that Jiangzhi Granule could attenuate NASH by suppressing TNF/NFκB signaling mediated macrophage M1-type polarization.


Subject(s)
Drugs, Chinese Herbal/pharmacology , Liver/drug effects , Macrophages/drug effects , NF-kappa B/metabolism , Network Pharmacology , Non-alcoholic Fatty Liver Disease/prevention & control , Phytochemicals/pharmacology , Tumor Necrosis Factor-alpha/metabolism , Animals , Chromatography, High Pressure Liquid , Disease Models, Animal , Liver/immunology , Liver/metabolism , Liver/pathology , Macrophages/immunology , Macrophages/metabolism , Male , Mice, Inbred C57BL , Non-alcoholic Fatty Liver Disease/immunology , Non-alcoholic Fatty Liver Disease/metabolism , Non-alcoholic Fatty Liver Disease/pathology , Phenotype , Protein Interaction Maps , Signal Transduction , Spectrometry, Mass, Electrospray Ionization , Tandem Mass Spectrometry
14.
Article in English | MEDLINE | ID: mdl-34158817

ABSTRACT

Alcoholic liver disease (ALD) is a liver disease caused by long-term alcohol consumption. ROS-mediated oxidative stress is the leading cause of ALD. Pien-Tze-Huang (PZH), a traditional formula, is famous in China. This study was designed to evaluate the effects and explore the potential mechanisms of PZH in ALD. Forty mice were randomly divided into five groups: control group (normal diet + vehicle), model group (ethanol diet + vehicle), PZH-L group (ethanol diet + PZH (0.125 g/kg)), PZH-M group (ethanol diet + PZH (0.25 g/kg)), and PZH-H group (ethanol diet + PZH (0.5 g/kg)). The mice were sacrificed, and their liver and blood samples were preserved. Liver steatosis, triglyceride (TG), total cholesterol, serum alanine aminotransferase (ALT), and aspartate aminotransferase (AST) levels were assayed. Malondialdehyde (MDA), glutathione peroxidase (GSH-PX), and total superoxide dismutase were identified using commercial kits. Oxylipins were profiled, and the data were analyzed. The AMPK/ACC/CPT1A pathway was identified using real-time polymerase chain reaction and western blotting. The PZH-H intervention significantly alleviated hepatic steatosis and injury and reduced the levels of liver TG and serum ALT and AST. In addition, MDA levels were markedly reduced, and GSH-PX activity significantly increased after PZH-H intervention. Finally, PZH-H increased the levels of 17-HETE, 15-HEPE, 9-HOTrE, 13-HOTrE, and 5,6-dihydroxy-8Z,11Z,14Z,17Z-eicosatetraenoic acid, and reduced PGE2 levels. PZH-H intervention also promoted the phosphorylation of AMPK and ACC, and the expression of CPT1A. In conclusion, PZH reduced oxidative stress and alleviated hepatic steatosis and injury. The mechanism was correlated with the oxylipin metabolites/AMPK/ACC/CPT1A axis.

15.
Zhen Ci Yan Jiu ; 45(10): 835-8, 2020 Oct 25.
Article in Chinese | MEDLINE | ID: mdl-33788451

ABSTRACT

According to the operative characteristics, the stimulated site and the curative effect-emerged site of bloodletting therapy, its clinical characteristics may be divided into three categories: a) local stimulation induced focus-local effect, b) local stimulation induced effect of the distal target organ (point-to-point distal effect), and c) special point stimulation induced broader effect of the whole body. Accordingly, the underlying mechanisms of clinical outcomes mainly involve the improvement of the local microcirculation and secondary changes of inflammatory substances for the first category (local focus). The point-to-point distal effect might mainly involve the innervation of nerve segments, while the broad effect of specific acupoint stimulation might involve multiple levels of the neuro-endocrine-immune system. The future research on the mechanisms of bloodletting should starts from its specific effects and the type of disease, which should not be generalized.


Subject(s)
Acupuncture Points , Bloodletting , Microcirculation , Treatment Outcome
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