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1.
Sci Bull (Beijing) ; 69(11): 1653-1659, 2024 Jun 15.
Article in English | MEDLINE | ID: mdl-38641514

ABSTRACT

Topological band theory has conventionally been concerned with the topology of bands around a single gap. Only recently non-Abelian topologies that thrive on involving multiple gaps were studied, unveiling a new horizon in topological physics beyond the conventional paradigm. Here, we report on the first experimental realization of a topological Euler insulator phase with unique meronic characterization in an acoustic metamaterial. We demonstrate that this topological phase has several nontrivial features: First, the system cannot be described by conventional topological band theory, but has a nontrivial Euler class that captures the unconventional geometry of the Bloch bands in the Brillouin zone. Second, we uncover in theory and probe in experiments a meronic configuration of the bulk Bloch states for the first time. Third, using a detailed symmetry analysis, we show that the topological Euler insulator evolves from a non-Abelian topological semimetal phase via. the annihilation of Dirac points in pairs in one of the band gaps. With these nontrivial properties, we establish concretely an unconventional bulk-edge correspondence which is confirmed by directly measuring the edge states via. pump-probe techniques. Our work thus unveils a nontrivial topological Euler insulator phase with a unique meronic pattern and paves the way as a platform for non-Abelian topological phenomena.

2.
Sci Bull (Beijing) ; 67(20): 2069-2075, 2022 Oct 31.
Article in English | MEDLINE | ID: mdl-36546106

ABSTRACT

Topological phases of matter have been extensively investigated in solid-state materials and classical wave systems with integer dimensions. However, topological states in non-integer dimensions remain almost unexplored. Fractals, being self-similar on different scales, are one of the intriguing complex geometries with non-integer dimensions. Here, we demonstrate fractal higher-order topological states with unprecedented emergent phenomena in a Sierpinski acoustic metamaterial. We uncover abundant topological edge and corner states in the acoustic metamaterial due to the fractal geometry. Interestingly, the numbers of the edge and corner states depend exponentially on the system size, and the leading exponent is the Hausdorff fractal dimension of the Sierpinski carpet. Furthermore, the results reveal the unconventional spectrum and rich wave patterns of the corner states with consistent simulations and experiments. This study thus unveils unconventional topological states in fractal geometry and may inspire future studies of topological phenomena in non-Euclidean geometries.

3.
Front Oncol ; 12: 843250, 2022.
Article in English | MEDLINE | ID: mdl-36387083

ABSTRACT

In this study, we aim to investigate the predictive value of serum vascular endothelial growth factor (VEGF) in evaluating treatment efficacy and long-term prognosis for patients with non-surgical esophageal squamous cell carcinoma (ESCC). The patients diagnosed with ESCC by histopathology who didn't receive surgical treatment were retrospectively analyzed. Through follow-up and prognostic analysis, we explored the value of serum VEGF changes before, during, and after radiotherapy for predicting treatment efficacy, and identified important indicators to construct the predictive model. Eighty-four patients were enrolled in this study, and the objective response rate (ORR) after treatment was 75.0%. The serum VEGF before, during and after radiotherapy were 108.2 ± 38.4, 98.6 ± 20.3 and 96.9 ± 20.0pg/ml, respectively. Staging and serum VEGF during radiotherapy were the independent factors affecting the treatment efficacy of non-surgical ESCC patients (OR=0.182 and 0.959, P<0.05). The median overall survival (OS) and progression-free survival (PFS) were 24.4 and 15.8 months. The 3-year, 5-year, 10-year OS rates and PFS rates were 35.7%, 26.2%, 14.4%, and 26.2%, 22.6%, 12.3%, respectively. By performing COX regression analysis, we found that the TNM stage, changes of VEGF after radiotherapy (∆VEGF2), and endoscopic histopathological response were the independent prognostic factors for OS and PFS (P<0.05). The R2 of the constructed prediction model was 0.328 and 0.362, and the C-index was 0.697 and 0.708, respectively. The follow-up time-dependent AUC showed that the predicted AUC was stable and greater than 0.7 as the follow-up time increased. For patients with non-surgical ESCC, those with low VEGF levels during radiotherapy had better treatment efficacy, and those with significant VEGF reduction after radiotherapy had a better prognosis. In summary, our results demonstrate that it is feasible to construct a model to evaluate and predict the efficacy and prognosis of patients with non-surgical ESCC based on serum VEGF measurement.

4.
Am J Transl Res ; 13(5): 4152-4166, 2021.
Article in English | MEDLINE | ID: mdl-34150005

ABSTRACT

Esophageal squamous cell carcinoma (ESCC) increases at fast rate of all cancer types in China, which urges the investigations of its potential mechanism. In this research, a highly expressed kinesin superfamily protein 22 (KIF22) was founded both in ESCC tissues and cancer cell lines. The following experiments pointed out that down-regulation of KIF22 remarkably restrained the malignant progression of ESCC cells. Besides, KIF22 knockdown promoted ESCC cells apoptosis and arrested cells in G0/G1 phase, while KIF22 also regulated the expression of cell cycle- and EMT-related proteins. Previous research revealed that the aberrant expressions of microRNAs (miRNAs) are related to tumors development. Based on the predict result, KIF22 was considered as the target of miR-122, which was demonstrated by luciferase reporter assay. miR-122 inhibitor could significantly reverse the function of KIF22 knockdown, including cell proliferation, migration and invasion. Furthermore, down-expressed miR-122 altered the function of KIF22 knockdown on cell cycle- and EMT-related proteins. In a word, this work illustrated the regulatory function of KIF22/miR-122 axis in ESSC and provided potential targets for potential targets for ESSC treatment.

5.
J Invest Dermatol ; 141(6): 1438-1449.e9, 2021 06.
Article in English | MEDLINE | ID: mdl-33333125

ABSTRACT

Non-neuronal acetylcholine (Ach) plays important roles in various aspects of cell biology and homeostasis outside the neural system. Keratinocytes (KCs) have a functional cholinergic mechanism, suggesting that they respond to Ach. However, the physiological role and mechanism by which Ach modulates wound KC behavior in both nondiabetic and diabetic conditions are unexplored. We found an enrichment in neurotransmitter-related pathways in microdissected-migrating nondiabetic and diabetic KCs. We showed that Ach upregulated TGFßRII through Src-extracellular signal‒regulated kinase 1/2 pathway to potentiate TGFß1-mediated epithelial‒mesenchymal transition in normoglycemic condition. Unexpectedly, KCs were nonresponsive to the elevated endogenous Ach in a hyperglycemic environment. We further showed that the activation of p38 MAPK in high glucose condition interferes with Src-extracellular signal‒regulated kinase 1/2 signaling, resulting in Ach resistance that could be rescued by inhibiting p38 MAPK. A better understanding of the cholinergic physiology in diabetic KCs could improve wound management and care. The finding suggests that mitigating the inhibitory effect of diabetic wound microenvironment has a direct clinical implication on the efficacy and safety of various wound healing agents to improve chronic diabetic wounds.


Subject(s)
Acetylcholine/metabolism , Diabetic Foot/drug therapy , Hyperglycemia/complications , Protein Kinase Inhibitors/pharmacology , p38 Mitogen-Activated Protein Kinases/antagonists & inhibitors , Animals , Blood Glucose/metabolism , Cell Line , Diabetes Mellitus, Experimental/blood , Diabetes Mellitus, Experimental/chemically induced , Diabetes Mellitus, Experimental/complications , Diabetes Mellitus, Experimental/metabolism , Diabetic Foot/blood , Diabetic Foot/etiology , Diabetic Foot/pathology , Epithelial-Mesenchymal Transition/drug effects , Humans , Hyperglycemia/blood , Hyperglycemia/chemically induced , Hyperglycemia/metabolism , Keratinocytes/pathology , MAP Kinase Signaling System/drug effects , Male , Mice , Protein Kinase Inhibitors/therapeutic use , Skin/cytology , Skin/drug effects , Skin/pathology , Streptozocin/administration & dosage , Wound Healing/drug effects , p38 Mitogen-Activated Protein Kinases/metabolism
6.
Med Sci Monit ; 26: e927221, 2020 Nov 27.
Article in English | MEDLINE | ID: mdl-33243967

ABSTRACT

BACKGROUND Esophageal cancer is a common gastrointestinal malignancy in China. We evaluated the efficacy and safety of adding Apatinib to concurrent chemoradiotherapy in patients with locally advanced esophageal squamous cell carcinoma. MATERIAL AND METHODS In this single-center retrospective study, we compared short-term efficacy, long-term efficacy, and adverse events between patients who received Apatinib and concurrent chemoradiotherapy (Apatinib group), and those who received only concurrent chemoradiotherapy (CCRT group). RESULTS Sixty-five patients with stage II and III esophageal squamous cell carcinoma were enrolled (31 in the Apatinib group, 34 in the CCRT group). After treatment, the therapy response rate (the sum of the complete and partial remission rates) was significantly higher in the Apatinib group than in the CCRT group (P=0.045); the complete remission rate was particularly higher in the Apatinib group. Median progression-free survival in the Apatinib group (12 months) was higher than that of the CCRT group (7 months), and the 1- and 2-year progression-free survival rates were significantly higher in the Apatinib group than in the CCRT group (47.0% vs. 30.3% and 20.2% vs. 12.1%, respectively; P=0.040). The main adverse effects of Apatinib treatment were elevated blood pressure, proteinuria, hand-foot syndrome, fatigue, and oral mucositis, all of which were level 1-2. Cox multivariate regression analysis indicated T stage and short-term efficacy were independent prognostic factors for overall and progression-free survival. CONCLUSIONS For patients with locally advanced esophageal squamous cell carcinoma, combining Apatinib with concurrent chemoradiotherapy can improve patient survival and significantly prolong progression-free survival, with tolerable adverse reactions.


Subject(s)
Chemoradiotherapy , Esophageal Neoplasms/pathology , Esophageal Neoplasms/therapy , Esophageal Squamous Cell Carcinoma/pathology , Esophageal Squamous Cell Carcinoma/therapy , Pyridines/adverse effects , Pyridines/therapeutic use , Aged , Esophageal Neoplasms/epidemiology , Esophageal Squamous Cell Carcinoma/epidemiology , Female , Humans , Incidence , Male , Multivariate Analysis , Neoplasm Staging , Nomograms , Prognosis , Proportional Hazards Models , Survival Analysis , Time Factors , Treatment Outcome
7.
Medicine (Baltimore) ; 99(37): e22194, 2020 Sep 11.
Article in English | MEDLINE | ID: mdl-32925794

ABSTRACT

DNA methylation is an important epigenetic regulatory mechanism in esophageal carcinoma (EC) and is associated with genomic instability and carcinogenesis. In the present study, we aimed to identify tumor biomarkers for predicting prognosis of EC patients.We downloaded mRNA expression profiles and DNA methylation profiles associated with EC from the Gene Expression Omnibus database. Differentially expressed and differentially methylated genes between tumor tissues and adjacent normal tissue samples were identified. Functional enrichment analyses were performed, followed by the construction of protein-protein interaction networks. Data were validated based on methylation profiles from The Cancer Genome Atlas. Candidate genes were further verified according to survival analysis and Cox regression analysis.We uncovered multiple genes with differential expression or methylation in tumor samples compared with normal samples. After taking the intersection of 3 differential gene sets, we obtained a total of 232 overlapping genes. Functional enrichment analysis revealed that these genes are related to pathways such as "glutathione metabolism," "p53 signaling pathway," and "focal adhesion." Furthermore, 8 hub genes with inversed expression and methylation correlation were identified as candidate genes. The abnormal expression levels of MSN, PELI1, and MTHFD2 were correlated with overall survival times in EC patients (P < .05). Only MTHFD2 was significantly associated with a pathologic stage according to univariate analysis (P = .037) and multivariate analysis (P = .043).Our study identified several novel EC biomarkers with prognostic value by integrated analysis of transcriptomic data and methylation profiles. MTHFD2 could serve as an independent biomarker for predicting prognosis and pathological stages of EC.


Subject(s)
Aminohydrolases/biosynthesis , Esophageal Neoplasms/genetics , Esophageal Neoplasms/pathology , Methylenetetrahydrofolate Dehydrogenase (NADP)/biosynthesis , Multifunctional Enzymes/biosynthesis , Biomarkers, Tumor , DNA Methylation , Databases, Genetic , Gene Expression Profiling , Genes, Neoplasm/physiology , Humans , Prognosis , Protein Interaction Maps , RNA, Messenger , Regression Analysis , Survival Analysis
8.
Oncol Lett ; 17(2): 1609-1616, 2019 Feb.
Article in English | MEDLINE | ID: mdl-30675220

ABSTRACT

To determine the radiosensitizing effect of apatinib on esophageal cancer cells, and to preliminarily investigate the underlying mechanism, KYSE-150 cells were treated with apatinib, x-ray or apatinib combined with x-ray, and compared with a blank control. It was observed that apatinib significantly inhibited vascular endothelial growth factor (VEGF) secretion and the proliferation of KYSE-150 cells in a dose-dependent manner. As the concentration of apatinib increased, the radiobiological parameters inactivation dose (D0), quasi domain does (Dq) and survival fraction (SF2) of KYSE-150 cells decreased, while the sensitization enhancement ratio SERD0 increased. The rate of apoptosis in cells treated with apatinib and x-ray was markedly higher compared with those of the blank control, x-ray and apatinib alone groups (P<0.05). The proportion of cells in the G2/M phase was significantly increased in the apatinib, x-ray and combination groups compared with the blank control group (P<0.05). Compared with the control and x-ray groups, combination treatment did not significantly alter the expression level of polyADP-ribose polymerase (PARP), although it significantly increased the expression of cleaved-PARP (P<0.05). Moreover, the expression of cell serine/threonine-protein kinase-2 (CHK2) was downregulated (P<0.05), whilst expression of the phosphorylated form, pCHK2, was significantly increased (P<0.05) in the combination group when compared with the control and x-ray groups. In conclusion, the present study suggested that apatinib increases the radiosensitivity of KYSE-150 esophageal cancer cells by inhibiting VEGF secretion and cell proliferation, and promoting apoptosis and cell cycle redistribution.

9.
Neurochem Res ; 43(8): 1587-1598, 2018 Aug.
Article in English | MEDLINE | ID: mdl-29948727

ABSTRACT

Arachidonic acid and docosahexaenoic acid (DHA) released by the action of phospholipases A2 (PLA2) on membrane phospholipids may be metabolized by lipoxygenases to the anti-inflammatory mediators lipoxin A4 (LXA4) and resolvin D1 (RvD1), and these can bind to a common receptor, formyl-peptide receptor 2 (FPR2). The contribution of this receptor to axonal or dendritic outgrowth is unknown. The present study was carried out to elucidate the distribution of FPR2 in the rat CNS and its role in outgrowth of neuronal processes. FPR2 mRNA expression was greatest in the brainstem, followed by the spinal cord, thalamus/hypothalamus, cerebral neocortex, hippocampus, cerebellum and striatum. The brainstem and spinal cord also contained high levels of FPR2 protein. The cerebral neocortex was moderately immunolabelled for FPR2, with staining mostly present as puncta in the neuropil. Dentate granule neurons and their axons (mossy fibres) in the hippocampus were very densely labelled. The cerebellar cortex was lightly stained, but the deep cerebellar nuclei, inferior olivary nucleus, vestibular nuclei, spinal trigeminal nucleus and dorsal horn of the spinal cord were densely labelled. Electron microscopy of the prefrontal cortex showed FPR2 immunolabel mostly in immature axon terminals or 'pre-terminals', that did not form synapses with dendrites. Treatment of primary hippocampal neurons with the FPR2 inhibitors, PBP10 or WRW4, resulted in reduced lengths of axons and dendrites. The CNS distribution of FPR2 suggests important functions in learning and memory, balance and nociception. This might be due to an effect of FPR2 in mediating arachidonic acid/LXA4 or DHA/RvD1-induced axonal or dendritic outgrowth.


Subject(s)
Axons/metabolism , Brain/metabolism , Dendrites/metabolism , Receptors, Lipoxin/biosynthesis , Spinal Cord/metabolism , Animals , Axons/chemistry , Axons/ultrastructure , Brain/ultrastructure , Brain Chemistry/physiology , Cell Survival/physiology , Central Nervous System/chemistry , Central Nervous System/metabolism , Central Nervous System/ultrastructure , Dendrites/chemistry , Dendrites/ultrastructure , Male , Rats , Rats, Wistar , Receptors, Lipoxin/analysis , Spinal Cord/chemistry , Spinal Cord/ultrastructure
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