Picometer-Scale Atomic Shifts Governing Subdisordered Structures in Diamond.

Diamond is considered the most promising next-generation semiconductor material due to its excellent physical characteristics. It has been more than three decades since the discovery of a special structure named n-diamond. However, despite extensive efforts, its crystallographic structure and properties are still unclear. Here, we show that subdisordered structures in diamond provide an explanation for the structural feature of n-diamond. Monocrystalline diamond with subdisordered structures is synthesized via the chemical vapor deposition method. Atomic-resolution scanning transmission electron microscopy characterizations combined with the picometer-precision peak finder technology and diffraction simulations reveal that picometer-scale shifts of atoms within cells of diamond govern the subdisordered structures. First-principles calculations indicate that the bandgap of diamond decreases rapidly with increasing shifting distance, in accordance with experimental results. These findings clarify the crystallographic structure and electronic properties of n-diamond and provide new insights into the bandgap adjustment in diamond.

Ultra-Large Compressive Plasticity of E-Ga2 O3 Thin Films at the Submicron Scale.

Gallium oxide (Ga2 O3 ) usually fractures in the brittle form, and achieving large plastic deformability to avoid catastrophic failure is in high demand. Here, ε-Ga2 O3 thin films with columnar crystals and partial unoccupied Ga sites are synthesized, and it is demonstrated that the ε-Ga2 O3 at the submicron scale can be compressed to an ultra-large plastic strain of 48.5% without cracking. The compressive behavior and related mechanisms are investigated by in situ transmission electron microscope nanomechanical testing combined with atomic-resolution characterizations. The serrated plastic flow and large strain burst are two major deformation forms of ε-Ga2 O3 during compression, which are attributed to the dislocation nucleation and avalanches, formation of new grains, and amorphization. The ultra-large compressive plasticity of ε-Ga2 O3 thin films at the submicron scale can inspire new applications of Ga2 O3 in micro- or nano- electronic and optoelectronic devices, especially those that require impact resistance during processing or service.

San Jie Tong Mai Fang Protects Against Atherosclerosis Progression by Regulating Macroautophagy through the PI3K/AKT/mTOR Signaling Pathway.

ABSTRACT: Many studies have confirmed that macrophage autophagy injury negatively impacts the pathogenesis of atherosclerosis (AS). Meanwhile, the phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) signaling pathway affects AS progression by regulating macrophage autophagy. We previously reported that the herbal formula San Jie Tong Mai Fang (SJTMF) elicits lipid regulatory and anti-inflammatory properties. Hence, the current study used an ApoE -/- high-fat diet-fed mouse model to determine whether SJTMF elicits protective effects against AS progression by means of the regulation of macrophage autophagy through the PI3K/AKT/mTOR signaling pathway. Our results show that SJTMF reduced the number of atherosclerotic plaques, foam cell formation, and intimal thickness in mouse aorta. In addition, SJTMF improved blood lipid metabolism and inflammatory levels in mice. We also observed that SJTMF caused macrophages to be polarized toward the M2 phenotype through the inhibition of the PI3K/AKT/mTOR signaling pathway. In addition, the abundances of LC3-II/I and beclin1 proteins-key autophagy molecules-were increased, whereas that of p62 was decreased, resulting in the promotion of macrophage autophagy. Taken together, these findings indicate that SJTMF may regulate the polarization of macrophages by inhibiting the PI3K/AKT/mTOR signaling pathway, thereby reducing atherosclerotic plaque damage in ApoE -/- mice, thereby promoting macrophage autophagy and eliciting a significant antiarteriosclerosis effect. Hence, SJTMF may represent a promising new candidate drug for the treatment of AS.

Hierarchically Engineered Manganite Thin Films with a Wide-Temperature-Range Colossal Magnetoresistance Response.

Colossal magnetoresistance is of great fundamental and technological significance in condensed-matter physics, magnetic memory, and sensing technologies. However, its relatively narrow working temperature window is still a severe obstacle for potential applications due to the nature of the material-inherent phase transition. Here, we realized hierarchical La0.7Sr0.3MnO3 thin films with well-defined (001) and (221) crystallographic orientations by combining substrate modification with conventional thin-film deposition. Microscopic investigations into its magnetic transition through electron holography reveal that the hierarchical microstructure significantly broadens the temperature range of the ferromagnetic-paramagnetic transition, which further widens the response temperature range of the macroscopic colossal magnetoresistance under the scheme of the double-exchange mechanism. Therefore, this work puts forward a method to alter the magnetic transition and thus to extend the magnetoresistance working window by nanoengineering, which might be a promising approach also for other phase-transition-related effects in functional oxides.

Evaluation of the effectiveness and safety of acupuncture in the treatment of premature ventricular contractions: A protocol for systematic review and meta-analysis.

BACKGROUND: Premature ventricular contractions are the most common type of arrhythmia. The clinical symptoms are mainly palpitations. In severe cases, syncope, angina pectoris and heart failure may occur, which seriously affect people's lives and ability to work. Antiarrhythmic drugs have many side effects and should not be taken for long periods. Acupuncture has a significant effect on the treatment of premature ventricular contractions. Therefore, to evaluate the effectiveness and safety of acupuncture in the treatment of premature ventricular contractions, we conducted this study, with the goal of providing a scientific methodology for this alternative treatment. METHODS: We searched PubMed, Embase, Web of Science, Cochrane Library, China National Knowledge Infrastructure, Wanfang Database, China Science Journal Database, and China Biomedical Literature Database. We selected all randomized clinical trials related to the use of acupuncture in the treatment of premature ventricular contractions published on or before October 10, 2021, and we will conduct literature screening and data extraction based on specific inclusion and exclusion criteria. We will use the bias risk assessment tool from the Cochrane Systematic Review Manual to evaluate the quality of the research selected for inclusion in our study. RevMan5.3 software will be used to perform statistical analysis on the data. RESULTS: The results of this study will provide evidence for the effectiveness and safety of acupuncture in the treatment of premature ventricular contractions. CONCLUSION: The purpose of this study is to explore the efficacy of acupuncture in the treatment of patients with premature ventricular contractions and to provide an effective reference for clinicians and patients on its use. INPLASY REGISTRATION NUMBER: INPLASY2021100040.

An in situ TEM nanoindentation-induced new nanostructure in cadmium zinc telluride.

Phase transformations occurring in a solid govern the structural and physical properties significantly. Nevertheless, deformation-induced phase transition in a soft-brittle solid has not been demonstrated yet. Soft-brittle cadmium zinc telluride (CZT) based instruments have produced technological breakthroughs in the semiconductor industry, and therefore their phase transformations have been widely investigated during the past 60 years. In this study, in situ transmission electron microscopy (TEM) nanoindentation was performed on CZT, and it was found that no brittle fracture occurred at a peak load of 41.9 µN, corresponding to a stress of 1.75 GPa. A new nanostructure induced by in situ TEM nanoindentation was observed, consisting of a single crystal, slip bands, stacking faults, a superlattice, a new tetragonal phase, and Moiré fringes. The new tetragonal phase was formed by partial Cd and Te atoms in the (111[combining macron]) plane slipping along the [1[combining macron]21[combining macron]] orientation, which was elucidated by ab initio simulations. It belongs to a tetragonal crystal system, and the lattice distances along the X and Y axes were 0.382 and 0.376 nm, respectively. Our findings provide new insights into the deformation-induced phase transformation for a soft-brittle solid, and have application potential in solar cells, radiation detectors, and medical imaging, quantum, flexible electronic and optoelectronic devices.

Dynamics of the charging-induced imaging instability in transmission electron microscopy.

Revolutionary microscopy technologies for aberration correction in spatial and energy aspects have exhibited continuous progress, pushing forward the information limit of materials research down to a scale of sub-angstrom and milli-electron voltage. Nevertheless, imaging quality could still suffer due to sample instability, e.g. the charging effect, which always comes along with electron microscopy characterizations. Herein, using a defocus estimation algorithm and an in situ image feature tracking method, we quantitatively studied the image drifting dynamics induced by the charging on transmission electron microscopy (TEM) carrier grids with tunable electrical conductivity. Experimental evidence clarifies the debate about the charge types, proving that the irradiation of the electron beam induces a positive charge on the grid sample of poor electrical conductivity. Such charge accumulation accounts for subsequent imaging instability, including the increase of defocus and the drift of lateral images. Particularly, the competition between charging and discharging was found to dynamically modulate the propagation of electron beam, resulting in a periodically reciprocating movement on TEM images. These findings enrich understanding on the dynamic principle of charging effects as well as the details of image drifting behaviors. It also suggests specific attention on the importance of conductivity control on a TEM specimen, beyond all the efforts for instrumental improvements.

Self-healing on mismatched fractured composite surfaces of SiC with a diameter of 180 nm.

Self-healing on fractured surfaces of silicon carbide (SiC) is highly desirable, to avoid the catastrophic failure of high-performance devices working at extreme environments. Nevertheless, self-healing on a fractured surface of an amorphous and crystalline (AAC) composite structure of a brittle nanowire (NW) has not been demonstrated. In this study, self-healing is demonstrated on mismatched fractured surfaces of the AAC composite structure of a brittle solid for a SiC NW with a diameter of 187 nm. Fracture strength is 10.18 GPa for the AAC structure, recovering 11.7% after self-healing on its mismatched fractured surfaces. To the best of our knowledge, we firstly report the self-healing on mismatched fractured surfaces of the AAC structure for a brittle NW. This is a breakthrough of the previous prediction that self-healing could not be realized on a brittle NW with a diameter over 150 nm. A growth of 3 nm was found after self-healing on the gap induced by mismatched fractured surfaces, which is different from previous reports for pure amorphous and monocrystalline brittle NWs. To reduce the potential energy, coherent rebonding and debonding were performed to realize the atomic migration to fill the gap, resulting in the growth of gap of 3 nm to perform self-healing. Our findings shed light on the potential of self-healing for design and fabrication of next-generation high-performance SiC devices used in the vacuum and aerospace industries.

Xuan Bi Tong Yu Fang Promotes Angiogenesis via VEGF-Notch1/Dll4 Pathway in Myocardial Ischemic Rats.

OBJECTIVE: To investigate the effect of Xuan Bi Tong Yu Fang (XBTYF) on angiogenesis via the vascular endothelial growth factor- (VEGF-) Notch1/delta-like 4 (Dll4) pathway. Materials and Methods. Sixty Sprague-Dawley rats were randomly divided into six groups: control, sham-operated, myocardial ischemia model, and XBTYF treatment at 3.2, 1.6, and 0.8 g/kg. Electrocardiography was performed to evaluate the successful establishment of the model. Hematoxylin-eosin staining and transmission electron microscopy were carried out to observe the morphology and mitochondrial structure in myocardial cells, respectively. TUNEL staining was performed to assess the degree of cell apoptosis. The expression of VEGF-A, Notch1, Dll4, Bcl2, Bax, caspase 3, caspase 9, and cytochrome-c (Cyt-c) was observed by western blot. RESULTS: XBTYF inhibited changes to the morphology and mitochondrial structure in cardiomyocyte and reduced cell apoptosis. Compared with the model group, XBTYF at all doses (3.2, 1.6, and 0.8 g/kg) reduced the expression of Notch1, Dll4, Bax, caspase 3, caspase 9, and Cyt-c, whereas expression of VEGF-A and Bcl2 was increased. CONCLUSION: XBTYF attenuated mitochondrial damage and cell apoptosis while promoting the angiogenesis of cardiomyocyte. The associated mechanism may be related to the VEGF-Notch1/Dll4 pathway.

Unprecedented Piezoresistance Coefficient in Strained Silicon Carbide.

Reports reveal that the piezoresistance coefficients of silicon carbide (SiC) nanowires (NWs) are 2 to 4 times smaller than those of their corresponding bulk counterparts. It is a challenge to eliminate contamination in adhering NWs onto substrates. In this study, a new setup was developed, in which NWs were manipulated and fixed by a goat hair and conductive silver epoxy in air, respectively, in the absence of any depositions. The goat hair was not consumed during manipulation of the NWs. The process took advantage of the stiffness and tapered tip of the goat hair, which is unlike the loss issue of beam sources in depositions. With the new fixing method, in situ transmission electron microscopy (TEM) electromechanical coupling measurements were performed on pristine SiC NWs. The piezoresistance coefficient and carrier mobility of SiC NW are -94.78 × 10-11 Pa-1 and 30.05 cm2 V-1 s-1, respectively, which are 82 and 527 times respectively greater than those of SiC NWs reported previously. We, for the first time, report that the piezoresistance coefficient of SiC NW is 17 times those of its bulk counterparts. These findings provide new insights to develop high performance SiC devices and to help avoid catastrophic failure when working in harsh environments.

Enhanced Thermal Conductivity of Epoxy Composites Filled with 2D Transition Metal Carbides (MXenes) with Ultralow Loading.

With the development of electronic devices such as integrated circuits toward the continual increase in power density and consumption, the efficient heat dissipation and low thermal expansion of materials become one of the most important issue. However, conventional polymers have the problem of poor thermal dissipation performance, which hinder application for electronic devices. In this work, the two-dimensional material, MXene (Ti3C2), is used as the reinforcement additive to optimize the thermal properties of polymers. We reported the preparation of multilayer Ti3C2 MXene by HF etching method and obtained few-layer Ti3C2 MXene by simple ultrasonication. Meanwhile, Ti3C2/epoxy composites were prepared by a solution blending method. The results show that the thermal properties of the composites are improved in comparison with the neat epoxy. Thermal conductivity value (0.587 W/mK) of epoxy composite with only 1.0 wt% Ti3C2 MXene fillers, is increased by 141.3% compared with that of neat epoxy. In addition, the composite presents an increased glass transition temperature, high thermal stability and lower coefficient of thermal expansion. This work is of great significance for the research of high-performance composite materials.

Ultrahigh Recovery of Fracture Strength on Mismatched Fractured Amorphous Surfaces of Silicon Carbide.

Nanowires (NWs) have been envisioned as building blocks of nanotechnology and nanodevices. In this study, NWs were manipulated using a weasel hair and fixed by conductive silver epoxy, eliminating the contaminations and damages induced by conventional beam depositions. The fracture strength of the amorphous silicon carbide was found to be 8.8 GPa, which was measured by in situ transmission electron microscopy nanomechanical testing, approaching the theoretical fracture limit. Here, we report that self-healing of mismatched fractured amorphous surfaces of brittle NWs was discovered. The fracture strength was found to be 5.6 GPa on the mismatched fractured surfaces, recovering 63.6% of that of pristine NWs. This is an ultrahigh recovery, due to the limits of reconstruction of dangling bonds on the fractured amorphous surfaces and the mismatched areas. Simulation by molecular dynamics showed fracture strength recovery of 65.9% on the mismatched fractured amorphous surfaces, which is in good agreement with the experimental results. Healing on the mismatched fractured amorphous surfaces is by reorganization of Si-C bonds forming Si-C and Si-Si bonds. The potential energy increases 2.6 eV in the reorganized Si-C bonds and decreases by 3.2 and 1.9 eV, respectively, in the formed Si-C and Si-Si bonds. These findings provide insights for the reliability, design, and fabrication of high performance NW-based devices, to avoid catastrophic failure working in harsh and extreme environments.

Deformation induced new pathways in silicon.

No in situ nanomechanical tests on damaged brittle materials have been demonstrated. This means that the transition route in damaged silicon (Si) under deformation is elusive. A gap is formed between abrasive machining and present nanomechanical tests, due to the unmatched nanostructure produced. In this study, a Si wedge is fabricated with a plateau of 80 nm in thickness. In situ dynamic nanoindentation is performed in a transmission electron microscope (TEM) on the damaged Si wedge, using a developed cube corner indenter with a tip radius of 66 nm. Nanotwins, slip bands and intersected stacking faults are observed in Si, which bridge the gap between abrasive machining and nanomechanical tests. A transition from Si-I to Si-VI is demonstrated by in situ atomic characterization, which is a new pathway in Si induced by in situ TEM nanoindentation. Ab initio calculations are conducted to elucidate the transition mechanism from Si-I to Si-VI. In the transition, the average potential energy is increased by 1.21 eV, and the average force exerted on an atom is 2.444 nN through compression and rotation. The findings propose new insights into the fabrication of high-performance devices and nanostructures in the electronics industry.

High Density Static Charges Governed Surface Activation for Long-Range Motion and Subsequent Growth of Au Nanocrystals.

How a heavily charged metal nanocrystal, and further a dual-nanocrystals system behavior with continuous electron charging? This refers to the electric dynamics in charged particles as well as the crystal growth for real metal particles, but it is still opening in experimental observations and interpretations. To this end, we performed an in-situ electron-beam irradiation study using transmission electron microscopy (TEM) on the Au nanocrystals that freely stand on the nitride boron nanotube (BNNT). Au nanocrystalline particles with sizes of 2⁻4 nm were prepared by a well-controlled sputtering method to stand on the BNNT surface without chemical bonding interactions. Au nanoparticles presented the surface atomic disorder, diffusion phenomena with continuous electron-beam irradiation, and further, the long-range motion that contains mainly the three stages: charging, activation, and adjacence, which are followed by final crystal growth. Firstly, the growth process undergoes the lattice diffusion and subsequently the surface-dominated diffusion mechanism. These abnormal phenomena and observations, which are fundamentally distinct from classic cases and previous reports, are mainly due to the overcharging of Au nanoparticle that produces a surface activation state in terms of high-energy plasma. This work therefore brings about new observations for both a single and dual-nanocrystals system, as well as new insights in understanding the resulting dynamics behaviors.

NRAGE is a potential diagnostic biomarker of hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is one of the most common cancers and a leading cause of cancer-related deaths worldwide. Early diagnosis of HCC remains a great challenge in clinic. Novel and effective biomarkers are in urgent need in early diagnosis of HCC.Serum levels of neurotrophin-receptor-interacting melanoma antigen-encoding gene homolog (NRAGE) were measured for 107 patients with HCC, 98 patients with benign liver diseases, and 89 healthy controls using quantitative real-time polymerase chain reaction. Receiver operating characteristic curve was applied to evaluate the diagnostic capacity of serum NRAGE in HCC.NRAGE expression was significantly higher in patients with HCC than in controls (all, P < .05). Moreover, its expression was tightly correlated with TNM stage (P = .004). NRAGE could distinguish patients with HCC from healthy controls with the area under the curve (AUC) of 0.874, yielding a sensitivity of 81.3% and a specificity of 78.7%. Additionally, in differentiation between benign liver diseases and HCC, the AUC value of NRAGE was 0.726, with a sensitivity of 63.6% and a specificity of 73.5%. Meanwhile, alpha-fetoprotein also could distinguish patients with HCC from benign liver disease cases, with an AUC of 0.677, a sensitivity of 64.4%, and a specificity of 60.2%.NRAGE could be a potential biomarker for HCC early diagnosis.

New Deformation-Induced Nanostructure in Silicon.

Nanostructures in silicon (Si) induced by phase transformations have been investigated during the past 50 years. Performances of nanostructures are improved compared to that of bulk counterparts. Nevertheless, the confinement and loading conditions are insufficient to machine and fabricate high-performance devices. As a consequence, nanostructures fabricated by nanoscale deformation at loading speeds of m/s have not been demonstrated yet. In this study, grinding or scratching at a speed of 40.2 m/s was performed on a custom-made setup by an especially designed diamond tip (calculated stress under the diamond tip in the order of 5.11 GPa). This leads to a novel approach for the fabrication of nanostructures by nanoscale deformation at loading speeds of m/s. A new deformation-induced nanostructure was observed by transmission electron microscopy (TEM), consisting of an amorphous phase, a new tetragonal phase, slip bands, twinning superlattices, and a single crystal. The formation mechanism of the new phase was elucidated by ab initio simulations at shear stress of about 2.16 GPa. This approach opens a new route for the fabrication of nanostructures by nanoscale deformation at speeds of m/s. Our findings provide new insights for potential applications in transistors, integrated circuits, diodes, solar cells, and energy storage systems.

In situ TEM observation of rebonding on fractured silicon carbide.

Silicon carbide (SiC) is widely used in harsh environments and under extreme conditions, including at high-power, high-temperature, high-current, high-voltage and high-frequency. The rebonding and self-matching of stack faults (SFs) is highly desirable to avoid catastrophic failure for SiC devices, especially for specific applications in the aerospace and nuclear power industries. In this study, a novel approach was developed using an eyebrow hair to pick up and transfer nanowires (NWs), in order to obtain in situ transmission electron microscope (TEM) images of the rebonding and self-matching of SFs at atomic resolution. During rebonding and healing, the electron beam was shut off. Rebonding on the fractured surfaces of monocrystalline and amorphous SiC NWs was observed by in situ TEM at room temperature. The fracture strength was 1.7 GPa after crack-healing, restoring 12.9% of that of a single crystal NW. Partial recrystallization along the <111> orientation and the self-matching of SFs are responsible for the rebonding of the monocrystalline NW. In comparison, the fracture strengths were 6.7 and 5.5 GPa for the first and second rebonding, respectively recovering 67% and 55% of that of an amorphous NW. Atomic diffusion contributed enormously to the rebonding on fractured surfaces of an amorphous NW, resulting in a healed surface consisting of an amorphous phase and crystallites. This rebonding function provides new insight into the fabrication of high-performance SiC devices for the aerospace, optoelectronic and semiconductor industries.

Enhanced thermal conductivity of epoxy composites filled with tetrapod-shaped ZnO.

Epoxy composites with ZnO powders characterized by different structures as inclusion are prepared and their thermal properties are studied. The experimental results demonstrate that the epoxy resins filled by tetrapod-shaped ZnO (T-ZnO) whiskers have the superior thermal transport property in comparison to ZnO micron particles (ZnO MPs). The thermal conductivity of ZnO/epoxy and T-ZnO/epoxy composites in different mass fraction (10, 20, 30, 40, 50 wt%) are respectively investigated and the suitable models are compared to explain the enhancement effect of thermal conductivity. The thermal conductivity of T-ZnO/epoxy composites with 50 wt% filler reaches 4.38 W m-1 K-1, approximately 1816% enhancement as compared to neat epoxy. In contrast, the same mass fraction of ZnO MPs are incorporated into epoxy matrix showed less improvement on thermal conduction properties. This is because T-ZnO whiskers act as a thermal conductance bridge in the epoxy matrix. In addition, the other thermal properties of T-ZnO/epoxy composites are also improved. Furthermore, the T-ZnO/epoxy composite also presents a much reduced coefficient of thermal expansion (∼28.1 ppm K-1) and increased glass transition temperature (215.7 °C). This strategy meets the requirement for the rapid development of advanced electronic packaging.

In Situ TEM Study of Interaction between Dislocations and a Single Nanotwin under Nanoindentation.

Nanotwinned (nt) materials exhibit excellent mechanical properties, and have been attracting much more attention of late. Nevertheless, the fundamental mechanism of interaction between dislocations and a single nanotwin is not understood. In this study, in situ transmission electron microscopy (TEM) nanoindentation is performed, on a specimen of a nickel (Ni) alloy containing a single nanotwin of 89 nm in thickness. The specimen is prepared using focused ion beam (FIB) technique from an nt surface, which is formed by a novel approach under indentation using a developed diamond panel with tips array. The stiffness of the specimen is ten times that of the pristine counterparts during loading. The ultrahigh stiffness is attributed to the generation of nanotwins and the impediment of the single twin to the dislocations. Two peak loads are induced by the activation of a new slip system and the penetration of dislocations over the single nanotwin, respectively. One slip band is parallel to the single nanotwin, indicating the slip of dislocations along the nanotwin. In situ TEM observation of nanoindentation reveals a new insight for the interaction between dislocations and a single nanotwin. This paves the way for design and preparation of high-performance nt surfaces of Ni alloys used for aircraft engines, gas turbines, turbocharger components, ducts, and absorbers.

miR-497 accelerates oxidized low-density lipoprotein-induced lipid accumulation in macrophages by repressing the expression of apelin.

microRNAs (miRNAs) play important roles in the pathogenesis of atherosclerosis. A previous study has reported that miR-497 is elevated in advanced atherosclerotic lesions in an apoE-deficient (apoE-/-) mouse model. The purpose of this study is to test whether miR-497 can modulate macrophage foam cell formation, an initiating event in atherosclerosis. We found that miR-497 was upregulated in THP-1 macrophages after treatment with oxidized low-density lipoprotein (oxLDL). Enforced expression of miR-497 promoted lipid accumulation and decreased cholesterol efflux in oxLDL-exposed THP-1 macrophages. In contrast, downregulation of miR-497 suppressed oxLDL-induced lipid accumulation in THP-1 macrophages. Apelin was identified to be a downstream target of miR-497. Overexpression of miR-497 significantly reduced the expression of apelin in THP-1 macrophages. Interestingly, delivery of a miR-497-resistant variant of apelin significantly inhibited lipid accumulation and enhanced cholesterol efflux in miR-497-overexpressing THP-1 macrophages in response to oxLDL. In addition, miR-497 expression was increased and negatively correlated with apelin protein expression in human atherosclerotic lesions. In conclusion, miR-497 contributes to oxLDL-induced lipid deposition in macrophages largely via targeting of apelin and thus represents a potential therapeutic target for atherosclerosis.