Publications by authors named "Bowen Yang"

131 Publications

Autophagy Blockade by Ai Du Qing Formula Promotes Chemosensitivity of Breast Cancer Stem Cells Via GRP78/β-Catenin/ABCG2 Axis.

Front Pharmacol 2021 3;12:659297. Epub 2021 Jun 3.

The Research Center for Integrative Medicine, School of Basic Medical Sciences, Guangzhou University of Chinese Medicine, Guangzhou, China.

Accumulating evidence suggests that the root of drug chemoresistance in breast cancer is tightly associated with subpopulations of cancer stem cells (CSCs), whose activation is largely dependent on taxol-promoting autophagy. Our pilot study identified GRP78 as a specific marker for chemoresistance potential of breast CSCs by regulating Wnt/β-catenin signaling. Ai Du Qing (ADQ) is a traditional Chinese medicine formula that has been utilized in the treatment cancer, particularly during the consolidation phase. In the present study, we investigated the regulatory effects and molecular mechanisms of ADQ in promoting autophagy-related breast cancer chemosensitivity. ADQ with taxol decreasing the cell proliferation and colony formation of breast cancer cells, which was accompanied by suppressed breast CSC ratio, limited self-renewal capability, as well as attenuated multi-differentiation. Furthermore, autophagy in ADQ-treated breast CSCs was blocked by taxol regulation of β-catenin/ABCG2 signaling. We also validated that autophagy suppression and chemosensitizing activity of this formula was GRP78-dependent. In addition, GRP78 overexpression promoted autophagy-inducing chemoresistance in breast cancer cells by stabilizing β-catenin, while ADQ treatment downregulated GRP78, activated the Akt/GSK3β-mediated proteasome degradation of β-catenin ubiquitination activation, and consequently attenuated the chemoresistance-promoted effect of GRP78. In addition, both mouse breast cancer xenograft and zebrafish xenotransplantation models demonstrated that ADQ inhibited mammary tumor growth, and the breast CSC subpopulation showed obscure adverse effects. Collectively, this study not only reveals the chemosensitizating mechanism of ADQ in breast CSCs, but also highlights the importance of GRP78 in mediating autophagy-promoting drug resistance β-catenin/ABCG2 signaling.
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http://dx.doi.org/10.3389/fphar.2021.659297DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8210424PMC
June 2021

Metformin Adjunct With Antineoplastic Agents for the Treatment of Lung Cancer: A Meta-Analysis of Randomized Controlled Trials and Observational Cohort Studies.

Front Pharmacol 2021 3;12:639016. Epub 2021 Jun 3.

Department of Pharmacy, The First Hospital of China Medical University, Shenyang, China.

Resistance to anticancer agents ensures a poor prognosis in patients with lung cancer. Metformin could enhance the anticancer effects of standard antineoplastic agents [traditional chemotherapy drugs, epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs), or immune checkpoint inhibitors (ICIs)]; however, it is unclear whether metformin can be combined with antineoplastic agents in the treatment of lung cancer. To explore the efficacy of combinational strategies, we performed a systematic review and meta-analysis for diabetic and non-diabetic patients with lung cancer. An electronic literature search was performed to obtain relevant randomized controlled trials (RCTs) and observational cohort studies. Hazard ratios (HR) with 95% confidence intervals (CI) of overall survival (OS) and progression-free survival (PFS) outcomes were extracted. Subgroup analysis by antineoplastic agents, study type, histology and clinical stage were investigated. 14 studies (three RCTs and eleven observational cohort studies) consisting 3,856 patients were included in the meta-analysis. Compared to standard antineoplastic agents alone (traditional chemotherapy drugs, EGFR-TKIs or ICIs), the antineoplastic agents combined with metformin significantly improved OS (HR 0.73, 95% CI 0.66-0.81, < 0.00001) and PFS (HR 0.72, 95% CI 0.59-0.88, = 0.001); a similar association was found in observational evidence. Limited data from RCTs showed no differences in OS or PFS. Metformin plus antineoplastic agents may improve survival outcomes of patients with lung cancer. Further investigation is needed.
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http://dx.doi.org/10.3389/fphar.2021.639016DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8209491PMC
June 2021

Duramycin radiosensitization of MCA-RH 7777 hepatoma cells through the elevation of reactive oxygen species.

J Cancer Res Ther 2021 Apr-Jun;17(2):543-546

Department of Radiology, Northwestern University, Chicago, Illinois, USA.

Objective: The objective of this study is to explore the radiosensitization effects of duramycin against the liver cancer hepatoma cells and relationship to reactive oxygen species (ROS) generation.

Materials And Methods: MCA-RH 7777 cells were treated with various combinations of duramycin concentrations and radiation doses. After the treatment, cell viabilities were determined by a cell proliferation assay; intracellular ROS levels were detected with the flow cytometric method.

Results: MCA-RH 7777 cell viability was found significantly reduced after combining duramycin and radiation exposure (comparing to that of either treatment alone). Increased intracellular ROS levels were observed in cells treated with combinations of duramycin and radiation.

Conclusion: Duramycin increased the intracellular ROS generation and also increased the radiosensitivity of MCA-RH 7777 cells.
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http://dx.doi.org/10.4103/jcrt.JCRT_284_18DOI Listing
June 2021

Comparative Analysis and in vitro Experiments of Signatures and Prognostic Value of Immune Checkpoint Genes in Colorectal Cancer.

Onco Targets Ther 2021 31;14:3517-3534. Epub 2021 May 31.

Department of Medical Oncology, The First Hospital of China Medical University, Shenyang, 110001, People's Republic of China.

Purpose: Immune checkpoints, as pivotal regulators of immune escape in cancer, can motivate the emergence of immune checkpoint inhibitors (ICIs). The aim of this study is to identify the expression of the immune checkpoint genes (ICGs) in colorectal cancer (CRC) and to relate their individual as well as combined expression to prognosis and therapeutic effectiveness in CRC.

Methods: RNA expression of 47 ICGs and clinical information of CRC patients were collected from two public databases to elucidate the expression levels and prognostic values of these ICGs in CRC. Then, the Shapiro-Wilk normality test was used to determine the normality of variables. Overall survival (OS) rates of each subset were found by Kaplan-Meier method, and the statistical significance was determined by the Log rank test ( < 0.05).

Results: The expression of 13 and 9 ICGs was significantly associated with CRC prognosis in The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) cohorts. A series of ICGs was found to be significantly associated with TMB, neoantigens and MMR in CRC indicating that the combination of immunotherapy treatment biomarkers and ICGs may achieve accurate prognostic stratification of CRC, and potentially identify CRC cases that might respond to checkpoint inhibitors (CPIs). The subsets of high or low PD1/PD-L1/IDO1 expression stratified by CD48 were accurately associated with prognosis in CRC. In addition, in vitro experiments confirmed that VTCN1(B7-H4)-KD increases anti-PD-L1-mediated NK cell cytotoxicity on CRC tumor cells.

Conclusion: Although the expression of a single immune-checkpoint molecule does not predict the efficacy of immunotherapy in CRC, our findings infer that subsets defined by ICGs are associated with prognosis and imply the possibility that VTCN1 and CD48 serve as new immunotherapeutic targets.
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http://dx.doi.org/10.2147/OTT.S304297DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8180296PMC
May 2021

Polyketide pesticides from actinomycetes.

Curr Opin Biotechnol 2021 Jun 5;69:299-307. Epub 2021 Jun 5.

State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China. Electronic address:

Natural product derived pesticides have increased in popularity worldwide because of their high efficacy, eco-friendly nature and favorable safety profile. The development of polyketide pesticides from actinomycetes reflects this increase in popularity in the past decades. These pesticides, which include avermectins, spinosyns, polynactins, tetramycin and their analogues, have been successfully applied in crop protection. Moreover, the advance of biotechnology has led to continuous improvement in the discovery and production processes. In this review, we summarize these polyketide pesticides, their activities and provide insight into their development. We also discuss engineering strategies and the current status of industrial production for these pesticides. Given that actinomycetes are known to produce a wide range of bioactive secondary metabolites, the description of pesticide development and high yield strain improvement presented herein will facilitate further development of these valuable polyketide pesticides from actinomycetes.
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http://dx.doi.org/10.1016/j.copbio.2021.05.006DOI Listing
June 2021

Intratumoral synthesis of nano-metalchelate for tumor catalytic therapy by ligand field-enhanced coordination.

Nat Commun 2021 06 7;12(1):3393. Epub 2021 Jun 7.

State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, 200050, People's Republic of China.

The iron gall ink-triggered chemical corrosion of hand-written documents is a big threat to Western cultural heritages, which was demonstrated to result from the iron gall (GA-Fe) chelate-promoted reactive oxygen species generation. Such a phenomenon has inspired us to apply the pro-oxidative mechanism of GA-Fe to anticancer therapy. In this work, we construct a composite cancer nanomedicine by loading gallate into a Fe-engineered mesoporous silica nanocarrier, which can degrade in acidic tumor to release the doped Fe and the loaded gallate, forming GA-Fe nanocomplex in situ. The nanocomplex with a highly reductive ligand field can promote oxygen reduction reactions generating hydrogen peroxide. Moreover, the resultant two-electron oxidation form of GA-Fe is an excellent Fenton-like agent that can catalyze hydrogen peroxide decomposition into hydroxyl radical, finally triggering severe oxidative damage to tumors. Such a therapeutic approach by intratumoral synthesis of GA-Fe nano-metalchelate may be instructive to future anticancer researches.
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http://dx.doi.org/10.1038/s41467-021-23710-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8184762PMC
June 2021

Development and validation of a nomogram for predicting stroke risk in rheumatoid arthritis patients.

Aging (Albany NY) 2021 Jun 3;13(11):15061-15077. Epub 2021 Jun 3.

Department of Clinical Epidemiology and Evidence-Based Medicine, The First Affiliated Hospital, China Medical University, Shenyang, China.

We developed and validated a nomogram to predict the risk of stroke in patients with rheumatoid arthritis (RA) in northern China. Out of six machine learning algorithms studied to improve diagnostic and prognostic accuracy of the prediction model, the logistic regression algorithm showed high performance in terms of calibration and decision curve analysis. The nomogram included stratifications of sex, age, systolic blood pressure, C-reactive protein, erythrocyte sedimentation rate, total cholesterol, and low-density lipoprotein cholesterol along with the history of traditional risk factors such as hypertensive, diabetes, atrial fibrillation, and coronary heart disease. The nomogram exhibited a high Hosmer-Lemeshow goodness-for-fit and good calibration ( > 0.05). The analysis, including the area under the receiver operating characteristic curve, the net reclassification index, the integrated discrimination improvement, and clinical use, showed that our prediction model was more accurate than the Framingham risk model in predicting stroke risk in RA patients. In conclusion, the nomogram can be used for individualized preoperative prediction of stroke risk in RA patients.
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http://dx.doi.org/10.18632/aging.203071DOI Listing
June 2021

Structural Monoclinicity and Its Coupling to Layered Magnetism in Few-Layer CrI.

ACS Nano 2021 Jun 2. Epub 2021 Jun 2.

Department of Physics, University of Michigan, 450 Church Street, Ann Arbor, Michigan 48109, United States.

Using polarization-resolved Raman spectroscopy, we investigate layer number, temperature, and magnetic field dependence of Raman spectra in one- to four-layer CrI. Layer-number-dependent Raman spectra show that in the paramagnetic phase a doubly degenerated E mode of monolayer CrI splits into one A and one B mode in -layer ( > 1) CrI due to the monoclinic stacking. Their energy separation increases in thicker samples until an eventual saturation. Temperature-dependent measurements further show that the split modes tend to merge upon cooling but remain separated until 10 K, indicating a failed attempt of the monoclinic-to-rhombohedral structural phase transition that is present in the bulk crystal. Magnetic-field-dependent measurements reveal an additional monoclinic distortion across the magnetic-field-induced layered antiferromagnetism-to-ferromagnetism phase transition. We propose a structural change that consists of both a lateral sliding toward the rhombohedral stacking and a decrease in the interlayer distance to explain our experimental observations.
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http://dx.doi.org/10.1021/acsnano.1c02868DOI Listing
June 2021

Interfacial Bulk Properties of Hole-Transporting Materials for Perovskite Solar Cells: Isomeric Triphenylamine-Based Enamines Spiro-OMeTAD.

ACS Appl Mater Interfaces 2021 May 29;13(18):21320-21330. Epub 2021 Apr 29.

Department of Polymer Chemistry and Technology, Kaunas University of Technology, Radvilenu Road 19, LT, 50245 Kaunas, Lithuania.

Here, we report on three new triphenylamine-based enamines synthesized by condensation of an appropriate primary amine with 2,2-diphenylacetaldehyde and characterized by experimental techniques and density functional theory (DFT) computations. Experimental results allow highlighting attractive properties including solid-state ionization potential in the range of 5.33-5.69 eV in solid-state and hole mobilities exceeding 10 cm/V·s, which are higher than those in spiro-OMeTAD at the same electric fields. DFT-based analysis points to the presence of several conformers close in energy at room temperature. The newly synthesized hole-transporting materials (HTMs) were used in perovskite solar cells and exhibited performances comparable to that of spiro-OMeTAD. The device containing one newly synthesized hole-transporting enamine was characterized by a power conversion efficiency of 18.4%. Our analysis indicates that the perovskite-HTM interface dominates the properties of perovskite solar cells. PL measurements indicate smaller efficiency for perovskite-to-new HTM hole transfer as compared to spiro-OMeTAD. Nevertheless, the comparable power conversion efficiencies and simple synthesis of the new compounds make them attractive candidates for utilization in perovskite solar cells.
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http://dx.doi.org/10.1021/acsami.1c03000DOI Listing
May 2021

Construction of mannose-modified polyethyleneimine-block-polycaprolactone cationic polymer micelles and its application in acute lung injury.

Drug Deliv Transl Res 2021 Apr 23. Epub 2021 Apr 23.

Key Laboratory of Drug Targeting and Drug Delivery Systems, West China School of Pharmacy, Sichuan University, Chengdu, 610041, China.

This study evaluated the D-mannose modified polyethyleneimine-block-polycaprolactone biomacromolecule copolymer micelles (PCL-PEI-mannose) as a targeted delivery of the glucocorticoid dexamethasone (DXM) to lung inflammation tissues and enhances the vehicle for its anti-inflammatory effects. Dexamethasone was encapsulated in the hydrophobic core of cationic polymer micelles by solvent evaporation. The polymeric micelles exhibited sustained-release within 48 h, good blood compatibility, and colloidal stability in vitro. The cellular uptake of mannose-modified micelles was higher compared with the non-modified micelles. And drug-loaded targeted micelles could inhibit the production of inflammatory factors in activated RAW264.7 cells. The distribution results indicated that drug-loaded targeted micelles highly improved the lung targeting ability, reduced the wet/dry ratio of injured lung tissue, and relieved the lung inflammation, accompanied by the decrease of inflammatory cell infiltration, myeloperoxidase activity, and inflammatory mediator levels in bronchoalveolar lavage fluid. These findings suggested that PCL-PEI-mannose delivery system could facilitate the lung-specific delivery and inhibit the inflammatory response. Collectively, PCL-PEI-mannose polymer micelles could be used as a potential delivery system for the treatment of acute lung injury (ALI).
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http://dx.doi.org/10.1007/s13346-021-00976-9DOI Listing
April 2021

Mechanism and Model for Optimizing Polytetrafluoroethylene Distribution to Improve the Electrical and Thermal Conductivity of Treated Carbon Fiber Paper in Fuel Cells.

ACS Appl Mater Interfaces 2021 Mar 22;13(12):14207-14220. Epub 2021 Mar 22.

School of Automotive Studies, Tongji University, Shanghai 201804, China.

Employing polytetrafluoroethylene (PTFE)-treated carbon fiber paper (CFP) as the substrate of the gas diffusion layer (GDL) is a common practice to improve water management in proton exchange membrane fuel cells (PEMFCs), but the resulting increase in electrical and thermal resistance is a critical problem that restricts the performance output of PEMFCs. Hence, studying the mechanism and prediction model for both the electrical and thermal conductivity in CFP is essential. This work established a mathematical graph theory model for CFP electrical and thermal conductivity prediction based on the observation and abstraction of the CFP characteristic structures. For the PTFE-treated CFP, the electrical and thermal conductivity of CFP can be effectively increased by optimizing the PTFE distribution in CFP. A "filter net effect" mechanism was proposed to reasonably explain PTFE distribution's influence on the CFP performance. Finally, the equivalent effect of multiple factors on conductivity was revealed using contour maps, which provides inspiration for further reducing the electrical and thermal resistance in CFP.
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http://dx.doi.org/10.1021/acsami.0c22930DOI Listing
March 2021

A Prognostic Nomogram of Colon Cancer With Liver Metastasis: A Study of the US SEER Database and a Chinese Cohort.

Front Oncol 2021 26;11:591009. Epub 2021 Feb 26.

Department of Medical Oncology, The First Hospital of China Medical University, Shenyang, China.

Background: Among colon cancer patients, liver metastasis is a commonly deadly phenomenon, but there are few prognostic models for these patients.

Methods: The clinicopathologic data of colon cancer with liver metastasis (CCLM) patients were downloaded from the Surveillance, Epidemiology and End Results (SEER) database. All patients were randomly divided into training and internal validation sets based on the ratio of 7:3. A prognostic nomogram was established with Cox analysis in the training set, which was validated by two independent validation sets.

Results: A total of 5,700 CCLM patients were included. Age, race, tumor size, tumor site, histological type, grade, AJCC N status, carcinoembryonic antigen (CEA), lung metastasis, bone metastasis, surgery, and chemotherapy were independently associated with the overall survival (OS) of CCLM in the training set, which were used to establish a nomogram. The AUCs of 1-, 2- and 3-year were higher than or equal to 0.700 in the training, internal validation, and external validation sets, indicating the favorable effects of our nomogram. Besides, whether in overall or subgroup analysis, the risk score calculated by this nomogram can divide CCLM patients into high-, middle- and low-risk groups, which suggested that the nomogram can significantly determine patients with different prognosis and is suitable for different patients.

Conclusion: Higher age, the race of black, larger tumor size, higher grade, histological type of mucinous adenocarcinoma and signet ring cell carcinoma, higher N stage, RCC, lung metastasis, bone metastasis, without surgery, without chemotherapy, and elevated CEA were independently associated with poor prognosis of CCLM patients. A nomogram incorporating the above variables could accurately predict the prognosis of CCLM.
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http://dx.doi.org/10.3389/fonc.2021.591009DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7962604PMC
February 2021

Molecular dynamics-guided receptor-dependent 4D-QSAR studies of HDACs inhibitors.

Mol Divers 2021 Feb 24. Epub 2021 Feb 24.

Department of Medicinal Chemistry, School of Pharmaceutical Science, NanChang University, Nanchang, 330006, China.

Histone deacetylases (HDACs) were highlighted as a novel category of anticancer targets. Several HDACs inhibitors were approved for therapeutic use in cancer treatment. Comparatively, receptor-dependent 4D-QSAR, LQTA-QSAR, is a new approach which generates conformational ensemble profiles of compounds by molecular dynamics simulations at binding site of enzyme. This work describes a receptor-dependent 4D-QSAR studies on hydroxamate-based HDACs inhibitors. The 4D-QSAR model was generated by multiple linear regression method of QSARINS. Leave-N-out cross-validation (LNO) and Y-randomization were performed to analysis of the independent test set and to verify the robustness of the model. Best 4D-QSAR model showed the following statistics: R = 0.8117, Q = 0.6881, Q = 0.6830, R = 0.884. The results may be used for further virtual screening and design for novel HDACs inhibitors. The receptor dependent 4D-QSAR model was developed for the hydroxamate derivatives as HDAC inhibitors by making use of molecular dynamics simulation to obtain conformational ensemble profile for each compound. The multiple linear regression method was used to generate 4D-QSAR model with the suitable predictive ability and the excellent statistical parameters.
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http://dx.doi.org/10.1007/s11030-021-10181-yDOI Listing
February 2021

Density Functional Theory-Assisted Synthesis of Self-Curing Epoxy-Acrylic Resin.

Front Chem 2020 20;8:595954. Epub 2021 Jan 20.

Shaanxi Key Laboratory of Chemical Additives for Industry, Shaanxi University of Science and Technology, Xi'an, China.

A density functional theory-assisted synthesis of self-curing epoxy-acrylic resin (EMPA) is described. The calculated quantum chemistry reaction index of the reacting monomer in the basic state, i.e., the radical reaction index (), is used as a guide to optimize the synthesis conditions. The reliability of the -assisted synthesis method is confirmed after evaluating the physical appearance, mechanical properties after curing, and thermal stability of the obtained EMPA. The special functional groups of the resin are characterized by Fourier transform infrared spectroscopy to prove the rationality of the reaction mechanism. The cross-sectional morphology characteristics of the cured resin are observed by field-emission scanning electron microscopy. The results show that the closer the molar ratio of monomers in the reaction to the ratio of of the reacting monomers, the better the polymerization performance.
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http://dx.doi.org/10.3389/fchem.2020.595954DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7855980PMC
January 2021

Hierarchical Image Segmentation Based on Nonsymmetry and Anti-Packing Pattern Representation Model.

IEEE Trans Image Process 2021 28;30:2408-2421. Epub 2021 Jan 28.

Image segmentation is the foundation of high-level image analysis and image understanding. How to effectively segment an image into regions that are "meaningful" to the human visual perception and ensure that the segmented regions are consistent at different resolutions is still a very challenging issue. Inspired by the idea of the Nonsymmetry and Anti-packing pattern representation Model in the Lab color space (NAMLab) and the "global-first" invariant perceptual theory, in this paper, we propose a novel framework for hierarchical image segmentation. Firstly, by defining the dissimilarity between two pixels in the Lab color space, we propose an NAMLab-based color image representation approach that is more in line with the human visual perception characteristics and can make the image pixels fast and effectively merge into the NAMLab blocks. Then, by defining the dissimilarity between two NAMLab-based regions and iteratively executing NAMLab-based merging algorithm of adjacent regions into larger ones to progressively generate a segmentation dendrogram, we propose a fast NAMLab-based algorithm for hierarchical image segmentation. Finally, the complexities of our proposed NAMLab-based algorithm for hierarchical image segmentation are analyzed in details. The experimental results presented in this paper show that our proposed algorithm when compared with the state-of-the-art algorithms not only can preserve more details of the object boundaries, but also it can better identify the foreground objects with similar color distributions. Also, our proposed algorithm can be executed much faster and takes up less memory and therefore it is a better algorithm for hierarchical image segmentation.
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http://dx.doi.org/10.1109/TIP.2021.3052359DOI Listing
January 2021

Enhanced up-conversion luminescence and temperature-sensing of GdVO:Ln with dual-wavelength excitation.

Dalton Trans 2021 Feb;50(6):2112-2122

College of Chemistry, Zhengzhou University, Green Catalysis Center, and College of Chemistry, Zhengzhou University Zhengzhou, Henan 450001, China.

There exists a tendency in the research of up-conversion materials to shift the excitation from 980 nm to multiple excitation wavelengths. A series of GdVO4:Ln3+ with similar sizes and irregular prism morphology were successfully prepared by a co-precipitation technique. A wide multi-color emission corresponding to different Ln3+ doping was also obtained under single excitation. It is worth pointing out that among all the studied samples, only the emission intensity of GdVO4:Yb3+/Er3+ excited at two-wavelengths (980 nm + 1550 nm) simultaneously was enhanced by a factor of 1.87, compared to the sum of emission intensities excited at two single-wavelengths separately. Moreover, to further enhance the up-conversion luminescence intensity, cation ions (Lu3+/Y3+) and anion ions (PO43-) were also doped into the host, and the luminous intensity was also improved to a certain extent. A possible mechanism for energy transfer and possible transitions were also suggested and discussed in detail using an energy level diagram. In addition, not only a high record value of Sa (0.0069 K-1) but also a high Sr (1.13% K-1) is achieved for GdVO4:Yb3+/Er3+ in the physiological temperature range (273-453 K). Combining a much intensified dual-wavelength up-conversion signal and good temperature-sensing properties, this work can be extended to the surges of other lanthanide ion doped systems pumped by using multiple-wavelength lasers, and can also open new possibilities for up-conversion color displays and anti-counterfeiting applications.
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http://dx.doi.org/10.1039/d0dt04159aDOI Listing
February 2021

Research trends in pharmacological modulation of tumor-associated macrophages.

Clin Transl Med 2021 01;11(1):e288

The Research Center for Integrative Medicine, School of Basic Medical Sciences, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, China.

As one of the most abundant immune cell populations in the tumor microenvironment (TME), tumor-associated macrophages (TAMs) play important roles in multiple solid malignancies, including breast cancer, prostate cancer, liver cancer, lung cancer, ovarian cancer, gastric cancer, pancreatic cancer, and colorectal cancer. TAMs could contribute to carcinogenesis, neoangiogenesis, immune-suppressive TME remodeling, cancer chemoresistance, recurrence, and metastasis. Therefore, reprogramming of the immune-suppressive TAMs by pharmacological approaches has attracted considerable research attention in recent years. In this review, the promising pharmaceutical targets, as well as the existing modulatory strategies of TAMs were summarized. The chemokine-chemokine receptor signaling, tyrosine kinase receptor signaling, metabolic signaling, and exosomal signaling have been highlighted in determining the biological functions of TAMs. Besides, both preclinical research and clinical trials have suggested the chemokine-chemokine receptor blockers, tyrosine kinase inhibitors, bisphosphonates, as well as the exosomal or nanoparticle-based targeting delivery systems as the promising pharmacological approaches for TAMs deletion or reprogramming. Lastly, the combined therapies of TAMs-targeting strategies with traditional treatments or immunotherapies as well as the exosome-like nanovesicles for cancer therapy are prospected.
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http://dx.doi.org/10.1002/ctm2.288DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7805405PMC
January 2021

Prediction of KRAS, NRAS and BRAF status in colorectal cancer patients with liver metastasis using a deep artificial neural network based on radiomics and semantic features.

Am J Cancer Res 2020 1;10(12):4513-4526. Epub 2020 Dec 1.

Department of Medical Oncology, The First Hospital of China Medical University 110001, Liaoning, China.

There is a critical need for development of improved methods capable of accurately predicting the RAS (KRAS and NRAS) and BRAF gene mutation status in patients with advanced colorectal cancer (CRC). The purpose of this study was to investigate whether radiomics and/or semantic features could improve the detection accuracy of RAS/BRAF gene mutation status in patients with colorectal liver metastasis (CRLM). In this retrospective study, 159 patients who had been diagnosed with CRLM in two hospitals were enrolled. All patients received lung and abdominal contrast-enhanced CT (CECT) scans prior to radiation therapy and chemotherapy. Semantic features were independently assessed by two radiologists. Radiomics features were extracted from the portal venous phase (PVP) of the CT scan for each patient. Seven machine learning algorithms were used to establish three scores based on the semantic, radiomics and the combination of both features. Two semantic and 851 radiomics features were used to predict the mutation status of RAS and BRAF using an artificial neural network method (ANN). This approach performed best out of the seven tested algorithms. We constructed three scores which were based on radiomics, semantic features and the combined scores. The combined score could distinguish between wild-type and mutant patients with an AUC of 0.95 in the primary cohort and 0.79 in the validation cohort. This study proved that the application of radiomics together with semantic features can improve non-invasive assessment of the gene mutation status of RAS (KRAS and NRAS) and BRAF in CRLM.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7783758PMC
December 2020

L. Suppresses Triple-Negative Breast Cancer Metastasis by Inhibiting Late-Phase Autophagy via Hif-1α/Caveolin-1 Signaling.

Front Pharmacol 2020 14;11:591400. Epub 2020 Dec 14.

Integrative Research Laboratory of Breast Cancer, The Second Clinical College, Guangzhou University of Chinese Medicine, Guangdong, China.

L. (SA) is a common herb for cancer treatment in the clinic, particularly during the consolidation phase to prevent occurrence or metastasis. Nevertheless, there are limited studies reporting the molecular mechanisms about its anti-metastatic function. It is well demonstrated that autophagy is one of the critical mechanisms accounting for metastasis and anti-cancer pharmacological actions of Chinese herbs. On the threshold, the regulatory effects and molecular mechanisms of SA in suppressing autophagy-related breast cancer metastasis were investigated in this study. findings demonstrated that SA potently suppressed the proliferation, colony formations well as metastasis process in triple-negative breast cancer. Network and biological analyses predicted that SA mainly targeted caveolin-1 (Cav-1) to induce anti-metastatic effects, and one of the core mechanisms was regulation of autophagy. Further experiments-including western blotting, transmission electron microscopy, GFP-mRFP-LC3 immunofluorescence, and lysosomal-activity detection-validated SA as a potent late-stage autophagic inhibitor by increasing microtubule-associated light chain 3-II (LC3-II) conversion, decreasing acidic vesicular-organelle formation, and inducing lysosomal dysfunction even under conditions of either starvation or hypoxia. Furthermore, the anti-autophagic and anti-metastatic activity of SA was Cav-1-dependent. Specifically, Cav-1 knockdown significantly facilitated SA-mediated inhibition of autophagy and metastasis. Furthermore, hypoxia inducible factor-1α (Hif-1α) overexpression attenuated the SA-induced inhibitory activities on Cav-1, autophagy, and metastasis, indicating that SA may have inhibited autophagy-related metastasis Hif-1α/Cav-1 signaling. In both mouse breast cancer xenograft and zebrafish xenotransplantation models, SA inhibited breast cancer growth and inhibited late-phase autophagy , which was accompanied by suppression of Hif-1α/Cav-1 signaling and the epithelial-mesenchymal transition. Overall, our findings not only indicate that SA acts as a novel late-phase autophagic inhibitor with anti-metastatic activities in triple-negative breast cancer, but also highlight Cav-1 as a regulator in controlling late-phase autophagic activity.
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http://dx.doi.org/10.3389/fphar.2020.591400DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7768086PMC
December 2020

Discovery of a series of 1H-pyrrolo[2,3-b]pyridine compounds as potent TNIK inhibitors.

Bioorg Med Chem Lett 2021 02 24;33:127749. Epub 2020 Dec 24.

Department of Medicinal Chemistry, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zuchongzhi Road, Shanghai 201203, China. Electronic address:

In an in-house screening, 1H-pyrrolo[2,3-b]pyridine scaffold was found to have high inhibition on TNIK. Several series of compounds were designed and synthesized, among which some compounds had potent TNIK inhibition with IC values lower than 1 nM. Some compounds showed concentration-dependent characteristics of IL-2 inhibition. These results provided new applications of TNIK inhibitors and new prospects of TNIK as a drug target.
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http://dx.doi.org/10.1016/j.bmcl.2020.127749DOI Listing
February 2021

Ascorbate Tumor Chemotherapy by An Iron-Engineered Nanomedicine-Catalyzed Tumor-Specific Pro-Oxidation.

J Am Chem Soc 2020 12 14;142(52):21775-21785. Epub 2020 Dec 14.

State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, P. R. China.

Ascorbate, a kind of polyhydroxy compound with a long history, has been extensively considered as an efficient antioxidant. However, only in the past several decades its pro-oxidation characteristic in the presence of transition metal catalysts has been gradually uncovered, attracting broad attention from researchers in chemistry and biology for benefiting various practical applications, such as anticancer therapy. In this work, we report catalytic ascorbate oxidation and reactive oxygen species generation for efficient tumor chemotherapy by an iron-engineered and ascorbate-loaded hollow mesoporous silica nanomedicine. The -Si-O-Fe- hybrid framework of nanomedicine not only enables acidity-triggered degradability and ascorbate release capability but also provides an abundant Fe ion source for catalyzing ascorbate oxidation, hydrogen peroxide formation, and subsequent Fenton reactions. The detailed chemical mechanism of Fe-catalyzed ascorbate oxidation has been explored in detail as two one-electron reaction processes, between which the first one involves the sequential Fe and O captures by ascorbate to form a metal-ascorbate-oxygen ternary complex favoring hydrogen peroxide generation. Both in vitro and in vivo results demonstrate the significantly enhanced anticancer efficacy of ascorbate oxidation catalyzed by the composite nanomedicine, demonstrating high feasibility of this synergistic therapeutic concept. It is expected that such a nanomedicine design would be beneficial to future advances in the field of ascorbate.
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http://dx.doi.org/10.1021/jacs.0c09984DOI Listing
December 2020

Could microtubule inhibitors be the best choice of therapy in gastric cancer with high immune activity: mutant DYNC1H1 as a biomarker.

Aging (Albany NY) 2020 11 20;12(24):25101-25119. Epub 2020 Nov 20.

Department of Medical Oncology, The First Hospital of China Medical University, Shenyang 110001, China.

Immune checkpoint blockade (ICB) has achieved unprecedented breakthroughs in various cancers, including gastric cancer (GC) with high immune activity (MSI-H or TMB-H), yet clinical benefits from ICB were moderate. Here we aimed to identify the most appropriate drugs which can improve outcomes in GC. We firstly compared MSI-H and TMB-H GC samples with normal samples in TCGA-STAD cohort, respectively. After that, Connectivity Map database repurposed nine candidate drugs (CMap score < -90). Then, microtubule inhibitors (MTIs) were screened as the significant candidate drugs with their representative gene sets strongly enriched ( < 0.05) via GSEA. GDSC database validated higher activities of some MTIs in GC cells with MSI-H and TMB-H ( < 0.05). Furthermore, some MTIs activities were positively associated with mutant Dynein Cytoplasmic 1 Heavy Chain 1 (DYNC1H1) ( < 0.05) based on NCI-60 cancer cell line panel. DYNC1H1 was high frequently alteration in GC and was positively associated with TMB-H and MSI-H. Mutant DYNC1H1 may be accompanied with down-regulation of MTIs-related genes in GC or change the binding pocket to sensitize MTIs. Overall, this study suggested that some MTIs may be the best candidate drugs to treat GC with high immune activity, especially patients with DYNC1H1 mutated.
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http://dx.doi.org/10.18632/aging.104084DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7803585PMC
November 2020

Systematic analysis of the molecular mechanisms of methotrexate therapy for rheumatoid arthritis using text mining.

Clin Exp Rheumatol 2020 Oct 17. Epub 2020 Oct 17.

Department of Medical Record Management Center, the First Af liated Hospital, China Medical University, Shenyang, China.

Objectives: The purpose of this study was to determine the expression of related genes in patients with rheumatoid arthritis (RA) treated with methotrexate (MTX), to identify hub genes, and to systematically analyse the functions, pathways, and networks of these genes.

Methods: The PubMed identifiers (PMIDs) of relevant publications were obtained from the PubMed database, and gene data were extracted from these documents using the text mining software PubTator. The Database for Annotation, Visualization and Integrated Discovery (DAVID) was used to obtain enriched Gene Ontology (GO) terms and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway information. In addition, the STRING database was used to construct a protein-protein interaction (PPI) network. Genes with which at least 10 other genes interacted were identified as hub genes.

Results: A total of 216 genes were identified as being associated with treatment efficacy for MTX, of which 14 pathways exhibited significant correlation (p<0.05, FDR<0.05). In addition, the constructed MTX treatment-related network consisted of 267 interactions. Fourteen genes were found to interact with at least 10 other genes (p<0.05, FDR<0.05) and identified as hub genes in the PPI network. These genes were JAK1, MAPK1, JUN, AKT1, MAPK14, MAPK8, FGB, FN1, ALB, B2M, IL2RB, GGH, IL2RA, and TP53.

Conclusions: This study will assist in elucidating the molecular mechanisms associated with the treatment efficacy of MTX for RA and provide a scientific rationale for guiding patient medication. However, the relationship between particular genes and the efficacy of MTX treatment for RA patients requires additional investigation.
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October 2020

Understanding the Activity of Single-Atom Catalysis from Frontier Orbitals.

Phys Rev Lett 2020 Oct;125(15):156001

Department of Physics and Astronomy, University of California, Irvine, California 92697-4575, USA.

The d-band center and charge states are often used to analyze the catalytic activity of noble or transition metal surfaces and clusters, but their applicability for single-atom catalysts (SACs) is unsure. This work suggests that the spatial structure and orientation of frontier orbitals which are closest to the Fermi level of SACs play a vital role. Taking adsorption of several molecules and CO oxidization on C_{3}N-supported single-atom Au as examples, we demonstrate that adsorption and catalytic activities are well correlated with the characteristics of frontier orbitals. This work provides an effective guidance for understanding the performance of single-atom catalysts.
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http://dx.doi.org/10.1103/PhysRevLett.125.156001DOI Listing
October 2020

AcrDB: a database of anti-CRISPR operons in prokaryotes and viruses.

Nucleic Acids Res 2021 01;49(D1):D622-D629

Nebraska Food for Health Center, Department of Food Science and Technology, University of Nebraska - Lincoln, Lincoln, NE 68588, USA.

CRISPR-Cas is an anti-viral mechanism of prokaryotes that has been widely adopted for genome editing. To make CRISPR-Cas genome editing more controllable and safer to use, anti-CRISPR proteins have been recently exploited to prevent excessive/prolonged Cas nuclease cleavage. Anti-CRISPR (Acr) proteins are encoded by (pro)phages/(pro)viruses, and have the ability to inhibit their host's CRISPR-Cas systems. We have built an online database AcrDB (http://bcb.unl.edu/AcrDB) by scanning ∼19 000 genomes of prokaryotes and viruses with AcrFinder, a recently developed Acr-Aca (Acr-associated regulator) operon prediction program. Proteins in Acr-Aca operons were further processed by two machine learning-based programs (AcRanker and PaCRISPR) to obtain numerical scores/ranks. Compared to other anti-CRISPR databases, AcrDB has the following unique features: (i) It is a genome-scale database with the largest collection of data (39 799 Acr-Aca operons containing Aca or Acr homologs); (ii) It offers a user-friendly web interface with various functions for browsing, graphically viewing, searching, and batch downloading Acr-Aca operons; (iii) It focuses on the genomic context of Acr and Aca candidates instead of individual Acr protein family and (iv) It collects data with three independent programs each having a unique data mining algorithm for cross validation. AcrDB will be a valuable resource to the anti-CRISPR research community.
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http://dx.doi.org/10.1093/nar/gkaa857DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7778997PMC
January 2021

Identification of CTLA-4 associated with tumor microenvironment and competing interactions in triple negative breast cancer by co-expression network analysis.

J Cancer 2020 9;11(21):6365-6375. Epub 2020 Sep 9.

Department of Medical Oncology, the First Hospital of China Medical University, Shenyang, China.

The study of CTLA-4 inhibitors has been one of the hot spots in the field of tumor immunotherapy. As the most immunogenic subtype of breast cancer, Triple negative breast cancer (TNBC) has a great potential in the treatment strategy. The aim of this study was to explore the relevant genes and pathways of CTLA-4 in TNBC and to explore the prognostic value, so as to provide a theoretical basis for clinical studies. We used the data from The Cancer Genome Atlas (TCGA) to analyze the expression of CTLA-4 in different types of breast cancer, and analyzed the TNBC data of CTLA-4 related co-expression genes by WGCNA and enrichment analysis. LncRNA-miRNA-CTLA-4 network was constructed to explore the immune infiltration and immune checkpoint associated with CTLA-4. The effect of CTLA-4 on clinical outcomes in TNBC patients was also evaluated. Finally, we used data from GEO database to verify the differences of CTLA-4 in different molecular types of breast cancer and related prognostic results. CTLA-4 was significantly higher in TNBC than in Luminal subtype and Her-2 + subtype (0.019 and 0.001, separately), and was significantly higher in ER and PR negative samples than in ER and PR positive samples (0.001). CTLA-4 related genes mainly enriched in biological process of leukocyte differentiation, regulation of leukocyte activation and T cell activation. Hsa-mir-92a was found to be a survival significance marker associated with CTLA-4 and lncRNA-miRNA-CTLA-4 network was constructed. The results of immune infiltration analysis showed that CTLA-4 was mainly related with T cell (0.74). For immune checkpoints analysis, CTLA-4 was mainly related to PDCD1(0.72) and CD28(0.64). In TNBC, high expression of CTLA-4 is related to good survival (0.0061). Results consistent with previous analysis were obtained in the GEO database, the expression of CTLA-4 in TNBC was significantly higher than that in non-TNBC (0.001), CTLA-4 was associated with favorable survival of TNBC (0.001). Among all types of breast cancer, the expression of CTLA-4 was the highest in TNBC.CTLA-4 in TNBC can be regulated by hsa-mir-92a to form ceRNA networks and influence the prognosis of TNBC patients through the leukocyte differentiation, regulation of leukocyte activation and T cell activation pathway.
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http://dx.doi.org/10.7150/jca.46301DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7532512PMC
September 2020

Molecular characterization, expression and immune functions of two C-type lectin from Venerupis philippinarum.

Fish Shellfish Immunol 2020 Dec 5;107(Pt A):260-268. Epub 2020 Oct 5.

Muping Coastal Environment Research Station, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai, 264003, PR China; Center for Ocean Mega-science, Chinese Academy of Sciences, Qingdao, Shandong, 266071, PR China. Electronic address:

In the present study, two C-type lectins (designated as VpClec-3 and VpClec-4) were identified and characterized from the manila clam Venerupis philippinarum. Multiple alignment and phylogenetic relationship analysis strongly suggested that VpClec-3 and VpClec-4 belong to the C-type lectin family. In nonstimulated clams, the VpClec-3 transcript was dominantly expressed in the hepatopancreas, while the VpClec-4 transcript was mainly expressed in gill tissues. Both VpClec-3 and VpClec-4 mRNA expression was significantly upregulated following Vibrio anguillarum challenge. Recombinant VpClec-4 (rVpClec-4) was shown to bind lipopolysaccharide (LPS) and glucan in vitro, whereas recombinant VpClec-3 (rVpClec-3) only bound to glucan. In addition, rVpClec-3 and rVpClec-4 displayed broad agglutination activities towards Vibrio harveyi, Vibrio splendidus and V. anguillarum, while no agglutination activities towards Enterobacter cloacae or Aeromonas hydrophila were observed in rVpClec-3. Moreover, hemocyte phagocytosis was significantly enhanced by rVpClec-3 and rVpClec-4. All the results showed that VpClecs function as pattern recognition receptors (PRRs) with distinct recognition spectra and are potentially involved in the innate immune responses of V. philippinarum.
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http://dx.doi.org/10.1016/j.fsi.2020.10.006DOI Listing
December 2020

Chemistry of Advanced Nanomedicines in Cancer Cell Metabolism Regulation.

Adv Sci (Weinh) 2020 Sep 7;7(18):2001388. Epub 2020 Aug 7.

State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai 200050 P. R. China.

Tumors reprogram their metabolic pathways to meet the bioenergetic and biosynthetic demands of cancer cells. These reprogrammed activities are now recognized as the hallmarks of cancer, which not only provide cancer cells with unrestricted proliferative and metastatic potentials, but also strengthen their resistance against stress conditions and therapeutic challenges. Although recent progress in nanomedicine has largely promoted the developments of various therapeutic modalities, such as photodynamic therapy, photothermal therapy, nanocatalytic therapy, tumor-starving/suffocating therapy, etc., the therapeutic efficacies of nanomedicines are still not high enough to achieve satisfactory tumor-suppressing effects. Therefore, researchers are obliged to look back to the essence of cancer cell biology, such as metabolism, for tailoring a proper therapeutic regimen. In this work, the characteristic metabolic pathways of cancer cells, such as aerobic respiration, glycolysis, autophagy, glutaminolysis, etc. are reviewed, to summarize the very recent advances in the smart design of nanomedicines that can regulate tumor metabolism for enhancing conventional therapeutic modalities. The underlying chemistry of these nanomedicines by which tumor metabolism is harnessed, is also discussed in a comprehensive manner. It is expected that by harnessing tumor metabolism cancer nanotherapeutics will be substantially improved in the future.
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http://dx.doi.org/10.1002/advs.202001388DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7509697PMC
September 2020

Tunable layered-magnetism-assisted magneto-Raman effect in a two-dimensional magnet CrI.

Proc Natl Acad Sci U S A 2020 Oct 23;117(40):24664-24669. Epub 2020 Sep 23.

Department of Physics, University of Michigan, Ann Arbor, MI 48109;

We used a combination of polarized Raman spectroscopy experiment and model magnetism-phonon coupling calculations to study the rich magneto-Raman effect in the two-dimensional (2D) magnet CrI We reveal a layered-magnetism-assisted phonon scattering mechanism below the magnetic onset temperature, whose Raman excitation breaks time-reversal symmetry, has an antisymmetric Raman tensor, and follows the magnetic phase transitions across critical magnetic fields, on top of the presence of the conventional phonon scattering with symmetric Raman tensors in -layer CrI We resolve in data and by calculations that the first-order phonon of the monolayer splits into an -fold multiplet in -layer CrI due to the interlayer coupling [Formula: see text] and that the phonons within the multiplet show distinct magnetic field dependence because of their different layered-magnetism-phonon coupling. We further find that such a layered-magnetism-phonon coupled Raman scattering mechanism extends beyond first-order to higher-order multiphonon scattering processes. Our results on the magneto-Raman effect of the first-order phonons in the multiplet and the higher-order multiphonons in -layer CrI demonstrate the rich and strong behavior of emergent magneto-optical effects in 2D magnets and underline the unique opportunities of spin-phonon physics in van der Waals layered magnets.
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http://dx.doi.org/10.1073/pnas.2012980117DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7547278PMC
October 2020

Observation of the polaronic character of excitons in a two-dimensional semiconducting magnet CrI.

Nat Commun 2020 Sep 22;11(1):4780. Epub 2020 Sep 22.

Department of Physics, University of Michigan, 450 Church Street, Ann Arbor, MI, 48109, USA.

Exciton dynamics can be strongly affected by lattice vibrations through electron-phonon coupling. This is rarely explored in two-dimensional magnetic semiconductors. Focusing on bilayer CrI, we first show the presence of strong electron-phonon coupling through temperature-dependent photoluminescence and absorption spectroscopy. We then report the observation of periodic broad modes up to the 8th order in Raman spectra, attributed to the polaronic character of excitons. We establish that this polaronic character is dominated by the coupling between the charge-transfer exciton at 1.96 eV and a longitudinal optical phonon at 120.6 cm. We further show that the emergence of long-range magnetic order enhances the electron-phonon coupling strength by ~50% and that the transition from layered antiferromagnetic to ferromagnetic order tunes the spectral intensity of the periodic broad modes, suggesting a strong coupling among the lattice, charge and spin in two-dimensional CrI. Our study opens opportunities for tailoring light-matter interactions in two-dimensional magnetic semiconductors.
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http://dx.doi.org/10.1038/s41467-020-18627-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7508859PMC
September 2020