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Light and sound are the most ubiquitous forms of waves, associated with a variety of phenomena and physical effects such as rainbows and echoes. Light and sound, both categorized as classical waves, have lately been brought into unexpected connections with exotic topological phases of matter. We are currently witnessing the onset of a second wave of active research into this topic. The past decade has been marked by fundamental advances comprising two-dimensional quantum Hall insulators and quantum spin and valley Hall insulators, whose topological properties are characterized using linear band topology. Here, going beyond these conventional topological systems, we focus on the latest frontiers, including non-Hermitian, nonlinear and non-Abelian topology as well as topological defects, for which the characterization of the topological features goes beyond the standard band-topology language. In addition to an overview of the current state of the art, we also survey future research directions for valuable applications.
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Building upon the bulk-boundary correspondence in topological phases of matter, disclinations have recently been harnessed to trap fractionally quantized density of states (DOS) in classical wave systems. While these fractional DOS have associated states localized to the disclination's core, such states are not protected from deconfinement due to the breaking of chiral symmetry, generally leading to resonances which, even in principle, have finite lifetimes and suboptimal confinement. Here, we devise and experimentally validate in acoustic lattices a paradigm by which topological states bind to disclinations without a fractional DOS but which preserve chiral symmetry. The preservation of chiral symmetry pins the states at the midgap, resulting in their protected maximal confinement. The integer DOS at the defect results in twofold degenerate states that, due to symmetry constraints, do not gap out. Our study provides a fresh perspective about the interplay between symmetry protection in topological phases and topological defects, with possible applications in classical and quantum systems alike.
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Weyl points-topological monopoles of quantized Berry flux-are predicted to spread to Weyl exceptional rings in the presence of non-Hermiticity. Here, we use a one-dimensional Aubry-Andre-Harper model to construct a Weyl semimetal in a three-dimensional parameter space comprising one reciprocal dimension and two synthetic dimensions. The inclusion of non-Hermiticity in the form of gain and loss produces a synthetic Weyl exceptional ring (SWER). The topology of the SWER is characterized by both its topological charge and non-Hermitian winding numbers. We experimentally observe the SWER and synthetic Fermi arc in a one-dimensional phononic crystal with the non-Hermiticity introduced by active acoustic components. Our findings pave the way for studying the high-dimensional non-Hermitian topological physics in acoustics.
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We report a three-dimensional (3D) topological insulator (TI) formed by stacking identical layers of Chern insulators in a hybrid real-synthetic space. By introducing staggered interlayer hopping that respects mirror symmetry, the bulk bands possess an additional Z_{2} topological invariant along the stacking dimension, which, together with the nontrivial Chern numbers, endows the system with a Z×Z_{2} topology. A 4-tuple topological index characterizes the system's bulk bands. Consequently, two distinct types of topological surface modes (TSMs) are found localized on different surfaces. Type-I TSMs are gapless and are protected by Chern numbers, whereas type-II gapped TSMs are protected by Z_{2} bulk polarization in the stacking direction. Remarkably, each type-II TSM band is also topologically nontrivial, giving rise to second-order topological hinge modes (THMs). Both types of TSMs and the THMs are experimentally observed in an elastic metacrystal.
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Topological notions in physics often emerge from adiabatic evolution of states. It not only leads to fundamental insight of topological protection but also provides an important approach for the study of higher-dimensional topological phases. In this work, we first demonstrate the transfer of topological boundary states (TBSs) across the bulk to the opposite boundary in an acoustic waveguide system. By exploring the finite-size induced minigap between two TBS bands, we unveil the quantitative condition for the breakdown of adiabaticity in the system by demonstrating the Landau-Zener transition with both theory and experiments. Our results not only serve as a foundation of future studies of dynamic state transfer but also inspire applications leveraging nonadiabatic transitions as a new degree of freedom.
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AIM: As one of the most common and lethal carcinomas, hepatocellular carcinoma (HCC) is a global health concern and affects millions of people worldwide. Current treatments for HCC are very limited due to its unclear pathogenesis. Here, we aim to further investigate the role of circCMTM3/microRNA (miR)-3619-5p in HCC. METHODS: Human blood samples were collected from HCC patients and healthy people. Quantitative reverse transcription-polymerase chain reaction and western blot analysis were undertaken to measure levels of circCMTM3, miR-3619-5p, SOX9, and exosome markers. The MTT, colony formation, and Transwell assays were used to examine the viability, migration, and invasion of human umbilical vein endothelial cells (HUVECs), respectively. Tube formation assay was used to assess angiogenesis. Dual luciferase assay was used to validate circCMTM3/miR-3619-5p and miR-3619-5p/SOX9 interactions. A nude mouse xenograft model was used to test the role of circCMTM3 in HCC in vivo. RESULTS: Levels of circCMTM3 in exosomes from HCC patients and cells were elevated. Knockdown of circCMTM3 greatly decreased viability, migration, and invasion of HUVECs, as well as angiogenesis. CircCMTM3 acted as a miR-3619-5p sponge and miR-3619-5p inhibitor reversed the effects of si-circCMTM3 on angiogenesis. MiR-3619-5p directly targeted SOX9 and modulated angiogenesis through SOX9. Furthermore, knockdown of circCMTM3 suppressed angiogenesis and HCC tumor growth in vivo. CONCLUSION: The exosome circCMTM3/miR-3619-5p/SOX9 axis from HCC cells promotes angiogenesis and thus contributes to HCC tumorigenesis.
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We report the first realization of a three-dimensional (3D) acoustic double-zero-index medium (DZIM) made of a cubic lattice of metal rods. While the past decade has seen several realizations of 2D DZIM, achieving such a medium in 3D has remained an elusive challenge. Here, we show how a fourfold degenerate point with conical dispersion can be induced at the Brillouin zone center, such that the material becomes a 3D DZIM with the effective mass density and compressibility simultaneously acquiring near-zero values. To demonstrate the functionalities of this new medium, we have fabricated an acoustic waveguide of 3D DZIM in form of a "periscope" with two 90° turns and observed tunneling of a normally incident planar wave through the waveguide yielding undistorted planar wave front at the waveguide exit. Our findings establish a practical route to realize 3D DZIM as an effective acoustic "void space" that offers unprecedented control over acoustic wave propagation.
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For classical waves, phase matching is vital for enabling efficient energy transfer in many scenarios, such as waveguide coupling and nonlinear optical frequency conversion. Here, we propose a temporal quasi-phase matching method and realize robust and complete acoustical energy transfer between arbitrarily detuned cavities. In a set of three cavities, A, B, and C, the time-varying coupling is established between adjacent elements. Analogy to the concept of stimulated Raman adiabatic passage, amplitudes of the two couplings are modulated as time-delayed Gaussian functions, and the couplings' signs are periodically flipped to eliminate temporal phase mismatching. As a result, robust and complete acoustic energy transfer from A to C is achieved. The non-reciprocal frequency conversion properties of our design are demonstrated. Our research takes a pivotal step towards expanding wave steering through time-dependent modulations and is promising to extend the frequency conversion based on state evolution in various linear Hermitian systems to nonlinear and non-Hermitian regimes.
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As a metabolic disruptor, bisphenol A (BPA) has been widely reported to disrupt lipid balance. Moreover, BPA has gained significant attention due to its estrogenic activity. While both ferroptosis and the G-protein-coupled estrogen receptor (GPER) have been implicated in lipid metabolism, their link to BPA-induced lipid accumulation remains unclear. In this study, chickens were randomly assigned to three groups and housed them for 4 weeks: a control group (0 µg/L BPA), a low dose group (50 µg/L BPA) and a high dose group (5000 µg/L BPA) to investigate the underlying mechanism of BPA-induced hepatotoxicity. Our results showed that BPA exposure significantly increased the contents of TG, TC, and LDL-C while decreasing HDL-C levels. We also found that BPA treatment altered the levels of genes involved in fatty acid ß-oxidation (ampkα, cpt-1, and ppaα), synthesis (acc, fas, scd-1, and srebp-1) and absorption (lpl and cd36). Moreover, the results showed that the BPA group had higher levels of IL-1ß, IL-18 and TNF-α. These results indicated that BPA exposure disrupted lipid metabolism and induced inflammation in the liver. We also demonstrated that BPA caused hepatic ferroptosis by raising iron content and the expression of genes related to lipid peroxidation (lpcat3, acsl4 and alox15), while reducing the expression of antioxidant system-associated genes (gpx4, slc7a11 and slc3a2). Importantly, BPA remarkably activated GPER expression in the liver. Interestingly, inhibition of GPER remarkably ameliorated BPA-induced lipid metabolism disorder, inflammatory response, and ferroptosis, indicating the crucial role of GPER in BPA-induced liver abnormalities. These findings highlight the link between GPER and ferroptosis in BPA-induced hepatotoxicity, providing new insights into the potential hazard of BPA.
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Enfermedad Hepática Inducida por Sustancias y Drogas , Ferroptosis , Animales , Receptores de Estrógenos/genética , Receptores de Estrógenos/metabolismo , Metabolismo de los Lípidos , Pollos/metabolismo , Hígado/metabolismo , Estrógenos/metabolismo , Compuestos de Bencidrilo/metabolismo , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Proteínas de Unión al GTP/metabolismo , LípidosRESUMEN
The durability of bioprosthetic heart valves is always compromised by the inherent antigenicity of biomaterials. Decellularization has been a promising approach to reducing the immunogenicity of biological valves. However, current methods are insufficient in eliminating all immunogenicity from the biomaterials, necessitating the exploration of novel techniques. In this study, we investigated using a novel detergent, fatty alcohol polyoxyethylene ether sodium sulfate (AES), to remove antigens from bovine pericardium. Our results demonstrated that AES treatment achieved a higher pericardial antigen removal rate than traditional detergent treatments while preserving the mechanical properties and biocompatibility of the biomaterials. Moreover, we observed excellent immune tolerance in the in vivo rat model. Overall, our findings suggest that AES treatment is a promising method for preparing biological valves with ideal clinical application prospects.
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To establish a model based on inflammation index and tumor burden score (TBS) to predict recurrence of hepatocellular carcinoma (HCC) after liver resection. A retrospective study was performed on 217 patients who diagnosed HCC underwent liver resection at Xiangya Hospital Central South University from June 1, 2017 to June 1, 2019. According to the receiver operating characteristic (ROC) curve, the optimal cut-off value of inflammatory index and the TBS was determined by the Youden index. Prediction performance was compared by the area under the receiver operating characteristic curve (AUC). Cox regression analysis was used to determine the risk factors for the recurrence of HCC after liver resection. According to the independent risk factors of the patients, a prediction model for HCC was established based on inflammation index and tumor burden score (TBS).The prediction performance of the model was compared with single index (TBS group and NLR group) and traditional HCC stage models (TNM stage and BCLC stage). MLR = 0.39, NLR = 2.63, PLR = 134, SII = 428 and TBS = 8.06 are the optimal cut-off values. AUC of SII, PLR, NLR, MLR and TBS were 0.643, 0.642, 0.642, 0.618 and 0.724respectively. MVI (P = 0.005), satellite nodule (P = 0.017), BCLC B-C stage (P = 0.013), NLR > 2.63 (P = 0.013), TBS > 8.06 (P = 0.017) are independent risk factors for the recurrence of HCC after liver resection. According to this study, the optimal inflammatory index NLR combined with TBS was obtained. The AUC of NLR-TBS model was 0.762, not only better than NLR group (AUC = 0.630) and TBS group (AUC = 0.671), also better than traditional BCLC (AUC = 0.620) and TNM (AUC = 0.587) stage models. Interestingly, we found that NLR and TBS should be good prognostic factor for recurrence of HCC after liver resection. The NLR-TBS model based the best inflammatory index (NLR) and TBS have a better prediction performance and the prediction performance of NLR-TBS model not only better than NLR group and TBS group, but better than BCLC and TNM stage models.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Carcinoma Hepatocelular/patología , Humanos , Inflamación/patología , Neoplasias Hepáticas/patología , Linfocitos/patología , Neutrófilos/patología , Pronóstico , Estudios Retrospectivos , Carga TumoralRESUMEN
Bioprosthetic heart valves (BHVs) used in clinics are fabricated via glutaraldehyde (GLUT) crosslinking, which results in cytotoxicity and causes eventual valve calcification after implantation into the human body; therefore, the average lifetime and application of BHVs are limited. To address these issues, the most commonly used method is modification with amino acids, such as glycine (GLY), which is proven to effectively reduce toxicity and calcification. In this study, we used the l-glutathione (GSH) in a new modification treatment based on GLUT-crosslinked bovine pericardium (BP) as the GLUT + GSH group, BPs crosslinked with GLUT as GLUT-BP (control group), and GLY modification based on GLUT-BP as the GLUT + GLY group. We evaluated the characteristics of BPs in different treatment groups in terms of biomechanical properties, cell compatibility, aldehyde group content detection, and the calcification content. Aldehyde group detection tests showed that the GSH can completely neutralize the residual aldehyde group of GLUT-BP. Compared with that of GLUT-BP, the endothelial cell proliferation rate of the GLUT + GSH group increased, while its hemolysis rate and the inflammatory response after implantation into the SD rat were reduced. The results show that GSH can effectively improve the cytocompatibility of the GLUT-BP tissue. In addition, the results of the uniaxial tensile test, thermal shrinkage temperature, histological and SEM evaluation, and enzyme digestion experiments proved that GSH did not affect the ECM stability and biomechanics of the GLUT-BP. The calcification level of GLUT-BP modified using GSH technology decreased by 80%, indicating that GSH can improve the anti-calcification performance of GLUT-BP. Compared with GLUT-GLY, GLUT + GSH yielded a higher cell proliferation rate and lower inflammatory response and calcification level. GSH can be used as a new type of anti-calcification agent in GLUT crosslinking biomaterials and is expected to expand the application domain for BHVs in the future.
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Small-diameter vascular grafts (diameter <6 mm) are in high demand in clinical practice. Neointimal hyperplasia, a common complication after implantation of small-diameter vascular grafts, is one of the common causes of graft failure. Modulation of local inflammatory responses is a promising strategy to attenuates neointimal hyperplasia. Vascular endothelial growth factor (VEGF) is an angiogenesis stimulator that also induces macrophage polarization and modulates inflammatory responses. In the present study, we evaluated the effect of VEGF on the neointima hyperplasia and local inflammatory responses of decellularized vascular grafts. In the presence of rhVEGF-165 in RAW264.6 macrophage culture, rhVEGF-165 induces RAW264.6 macrophage polarization to M2 phenotype. Decellularized bovine internal mammary arteries were implanted into the subcutaneous and infrarenal abdominal aorta of New Zealand rabbits, with rhVEGF-165 applied locally to the adventitial of the grafts. The vascular grafts were removed en-bloc and submitted to histological and immunofluorescence analyses on days 7 and 28 following implantation. The thickness of the fibrous capsule and neointima was thinner in the VEGF group than that in the control group. In the immunofluorescence analysis, the number of M2 macrophages and the ratio of M2/M1 macrophages in vascular grafts in the VEGF group were higher than those in the control group, and the proinflammatory factor IL-1 was expressed less than in the control group, but the anti-inflammatory factor IL-10 was expressed more. In conclusion, local VEGF administration attenuates neointimal hyperplasia in decellularized small-diameter vascular grafts by inducing macrophage M2 polarization and modulating the inflammatory response.
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The recent discovery and realizations of higher-order topological insulators enrich the fundamental studies on topological phases. Here, we report three-dimensional (3D) wave-steering capabilities enabled by topological boundary states at three different orders in a 3D phononic crystal with nontrivial bulk topology originated from the synergy of mirror symmetry of the unit cell and a non-symmorphic glide symmetry of the lattice. The multitude of topological states brings diverse possibilities of wave manipulations. Through judicious engineering of the boundary modes, we experimentally demonstrate two functionalities at different dimensions: 2D negative refraction of sound wave enabled by a first-order topological surface state with negative dispersion, and a 3D acoustic interferometer leveraging on second-order topological hinge states. Our work showcases that topological modes at different orders promise diverse wave steering applications across different dimensions.
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OBJECTIVES: Pancreatic carcinoma (PC) has become the fourth leading cause of cancer deaths. Long noncoding RNA DUXAP8 has also been reported to play a regulatory role in PC progression. However, its molecular mechanism in PC is not fully elucidated. METHODS: Quantitative real-time polymerase chain reaction was used to detect the levels of DUXAP8, microRNA (miR)-448, Wilms tumor 1-associating protein (WTAP), focal adhesion kinase (Fak), and matrix metallopeptidase 2/9. Western blotting was carried out to detect matrix metallopeptidase 2/9, WTAP, Fak, and p-Fak. The interaction between DUXAP8 and miR-448 as well as WTAP and miR-448 was validated by bioinformatics and dual-luciferase reporter assays. Transwell assay was used to analyze cell invasion and migration. 3-[4,5-Dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide assay was used to analyze cell proliferation. RESULTS: DUXAP8 was upregulated, whereas miR-448 was downregulated in PC tissue and cells. Meanwhile, DUXAP8 knockdown or miR-448 overexpression inhibited migration, invasion, and proliferation of PC cells. DUXAP8 directly targeted miR-448, and miR-448 directly bound to WTAP. Downregulation of miR-448 reversed the inhibition of migration and invasion of PC cells by DUXAP8 knockdown. CONCLUSIONS: DUXAP8 sponges miR-448 to modulate migration, invasion, and proliferation of PC cells, indicating a novel mechanistic role of DUXAP8 in the regulation of PC progression.
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Proteínas de Ciclo Celular/genética , Movimiento Celular/genética , Quinasa 1 de Adhesión Focal/genética , Regulación Neoplásica de la Expresión Génica , MicroARNs/genética , Neoplasias Pancreáticas/genética , Factores de Empalme de ARN/genética , ARN Largo no Codificante/genética , Secuencia de Bases , Proteínas de Ciclo Celular/metabolismo , Línea Celular , Línea Celular Tumoral , Proliferación Celular/genética , Quinasa 1 de Adhesión Focal/metabolismo , Células HEK293 , Humanos , Invasividad Neoplásica , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patología , Factores de Empalme de ARN/metabolismo , Homología de Secuencia de Ácido Nucleico , Transducción de Señal/genéticaRESUMEN
BACKGROUND: Antineoplastic activity of atractylenolide III (ATL) has been reported in several malignant tumors. However, its activity has not been completely clarified in hepatocellular carcinoma (HCC). Herein, anticancer effects and underlying molecular mechanisms of ATL were investigated in HCC cells in vitro. METHODS: Cell viability was evaluated by CCK-8 assay. Cell migration and invasion were evaluated using the transwell assay. TUNEL staining was performed to evaluate cell apoptosis. Protein expression was measured by western blotting analysis. Online database TargetScan and luciferase reporter gene analysis were performed to validate FGFR1 as a target of miR-195-5p. RESULTS: HepG2 and SMMC7721 cell growth, migration, and invasion were inhibited by ATL treatment in a dose-dependent pattern. ATL treatment-induced apoptosis of HepG2 and SMMC7721 cells. Intriguingly, ATL treatment unexpectedly inhibited FGFR1 protein expression in HepG2 and SMMC7721 cells. Knockdown of FGFR1 inhibited proliferation, migration, and invasion, and evoked apoptosis of HepG2 and SMMC7721 cells. We also found that ATL treatment could increase the expression of miR-195-5p, which as a posttranscriptional targeted FGFR1. In HCC tissues, miR-195-5p expression is negatively correlated with FGFR1. Furthermore, the antiproliferative and proapoptotic roles of miR-195-5p were neutralized by overexpressed FGFR1 in HCC cells. CONCLUSION: ATL effectively repressed growth and induced apoptosis of human HCC cells through the upregulation of miR-195-5p to downregulate FGFR1 expression. PRACTICAL APPLICATIONS: Atractylenolide III as a bioactive anticancer adjuvant medication will provide chemosensitization strategy for reversing the drug resistance of HCC.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , MicroARNs , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/genética , Línea Celular Tumoral , Regulación Neoplásica de la Expresión Génica , Células Hep G2 , Humanos , Lactonas , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/genética , MicroARNs/genética , Receptor Tipo 1 de Factor de Crecimiento de Fibroblastos/genética , SesquiterpenosRESUMEN
BACKGROUND: Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related deaths worldwide, but there is a shortage of effective biomarkers for its diagnosis. AIM: To explore blood exosomal micro ribonucleic acids (miRNAs) as potential biomarkers for HCC diagnosis. RESULTS: The principal component analysis suggested that daily alcohol consumption could alter the blood exosomal miRNA profiles of hepatitis B virus positive non-HCC patients through miR-3168 and miR-223-3p. The miRNA profiles also revealed the tumor stages of HCC patients. High expression of miR-455-5p and miR-30c-5p, which significantly correlated with better overall survival in tumor tissues, could also be detected in blood exosomes. Two pairs of miRNAs (miR-584-5p/miR-106-3p and miR-628-3p/miR-941) showed a 94.1% sensitivity and 68.4% specificity to differentiate HCC patients from non-HCC patients. The specificity of the combination was substantially influenced by alcohol consumption habits. CONCLUSION: This study suggested that blood exosomal miRNAs can be used as new non-invasive diagnostic tools for HCC. However, their accuracy could be affected by tumor stage and alcohol consumption habits.
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We present a design of acoustic frequency filter based on a two-dimensional anisotropic phononic crystal. The anisotropic band structure exhibits either a directional or a combined (global + directional) bandgap at certain frequency regions, depending on the geometry. When the time-reversal symmetry is broken, it may introduce a topologically nontrivial bandgap. The induced nontrivial bandgap and the original directional bandgap result in various interesting wave propagation behaviors, such as frequency filter. We develop a tight-binding model to characterize the effective Hamiltonian of the system, from which the contribution of anisotropy is explicitly shown. Different from the isotropic cases, the Zeeman-type splitting is not linear and the anisotropic bandgap makes it possible to achieve anisotropic propagation characteristics along different directions and at different frequencies.
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We propose a simple two-dimensional acoustic crystal to realize topologically protected edge states for acoustic waves. The acoustic crystal is composed of a triangular array of core-shell cylinders embedded in a water host. By utilizing the point group symmetry of two doubly degenerate eigenstates at the Γ point, we can construct pseudo-time-reversal symmetry as well as pseudo-spin states in this classical system. We develop an effective Hamiltonian for the associated dispersion bands around the Brillouin zone center, and find the inherent link between the band inversion and the topological phase transition. With numerical simulations, we unambiguously demonstrate the unidirectional propagation of acoustic edge states along the interface between a topologically nontrivial acoustic crystal and a trivial one, and the robustness of the edge states against defects with sharp bends. Our work provides a new design paradigm for manipulating and transporting acoustic waves in a topologically protected manner. Technological applications and devices based on our design are expected in various frequency ranges of interest, spanning from infrasound to ultrasound.