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1.
Transl Cancer Res ; 13(5): 2372-2386, 2024 May 31.
Article in English | MEDLINE | ID: mdl-38881946

ABSTRACT

Background: Chidamide (CHI) is a subtype-selective histone deacetylase inhibitor (HDACI) developed in China and approved as a second-line treatment combined with the aromatase inhibitor for hormone receptor-positive (HR+)/human epidermal growth factor receptor 2-negative (HER2-) advanced breast cancer. However, drug resistance is commonly occurred after a long period of medication. This study aimed to investigate the characterization of induced resistance to CHI and explore the potential cross-resistance to chemotherapeutic agents. Methods: CHI with gradually increasing concentrations was added to breast cancer MCF7 cells to establish a CHI-resistant MCF7 (MCF7-CHI-R) cell line. Cell counting kit-8 (CCK-8) assays were performed to detect half-maximal inhibitory concentration (IC50) of CHI. Colony formation was used to determine the proliferation inhibition rate. Western blot analysis was conducted to detect expressions of protein related with cell cycle, apoptosis, ferroptosis, and histone deacetylase (HDAC). Flow cytometry was used to analyze apoptosis and cell cycle. Results: The IC50 value of CHI of MCF7-CHI-R cells was increased in comparison with MCF7 cells. And CHI led to cell cycle arrest and ferroptosis, which were not exhibited in MCF7-CHI-R cells. Moreover, HDAC activity decreased in MCF7-CHI-R cells in comparison with MCF7 cells, and HDAC1 and HDAC10 might be involved in the resistance to CHI. In addition, MCF7-CHI-R cells were resistant to gemcitabine (GEM), doxorubicin (ADM), docetaxel (DXT), albumin-bound paclitaxel (nab-PTX) and paclitaxel (PTX). Conclusions: The MCF7-CHI-R was established and the anti-ferroptosis pathway activation was involved in the resistance of MCF-CHI-R cells. Also, MCF7-CHI-R cells were resistant to GEM, ADM, DXT, nab-PTX and PTX.

2.
J Gastrointest Oncol ; 15(2): 630-640, 2024 Apr 30.
Article in English | MEDLINE | ID: mdl-38756629

ABSTRACT

Background: After the failure of standard first- and second-line treatments, including oxaliplatin, irinotecan, and 5-fluorouracil (5-FU) combined with targeted drugs, the currently recommended third-line regimens for metastatic colorectal cancer (mCRC) include TAS-102, regorafenib, and fruquintinib. However, these regimens have the drawbacks of mediocre efficacy, substantive side effects, and high cost. Therefore, more effective, economical regimens with fewer side effects are needed in clinical practice. In this study, we assessed the efficacy and safety of gemcitabine plus raltitrexed or S-1 as a third- or later-line treatment in comparison to those of standard third-line therapies for patients with mCRC. Methods: Patients with previous failures of at least two lines of standard therapy with oxaliplatin, 5-FU, irinotecan, or capecitabine combined with targeted drugs were included. The participants received standard third-line therapies (including TAS-102, regorafenib, and fruquintinib) or gemcitabine plus raltitrexed or S-1 until disease progression, death, or intolerable toxicity arose. Imaging follow-up was performed every 3 months during their treatment. Progression-free survival (PFS) and overall survival (OS) were recorded. Cox regression analysis was used to investigate the potential predictors of survival. Results: From April 2018 to October 2022, 60 patients with mCRC were enrolled in our study. The numbers of patients in the chemotherapy, fruquintinib, regorafenib, and TAS-102 groups were 13, 15, 17, and 15, respectively; the median OS of the four groups was 7.4, 6.1, 8.3, and 6.7 months (P=0.384), respectively; the median PFS was 4.1, 3.4, 4.4, and 2.3 months (P=0.656), respectively; the overall response rate was 7.69%, 6.67%, 0.00%, and 13.33%, respectively; and the disease control rate was 61.54%, 60.00%, 70.59%, and 60.00%, respectively. Additionally, multivariate analysis revealed that primary lesion located in the rectum was adverse independent prognostic factors for OS. A typical case is presented in this article. Conclusions: The gemcitabine plus raltitrexed or S-1 regimen is a potential regimen with tolerable adverse reactions and low cost for patients with mCRC.

3.
Transl Cancer Res ; 12(10): 2806-2822, 2023 Oct 31.
Article in English | MEDLINE | ID: mdl-37969383

ABSTRACT

Background: Hepatocellular carcinoma (HCC) is one of the most common malignancies worldwide, with the highest incidence in East Asia, and hepatitis B virus (HBV) infection is the most common cause of HCC in Asian population. The immune system is closely related to the development of HCC and plays an important role in the treatment of this disease. In this study, we analyzed the data of HCC from The Cancer Genome Atlas (TCGA) database and constructed a risk-score prognostic model based on immune genes of an Asian HCC population, aiming to provide new perspectives for clinical treatment and management of HCC in Asian population. Methods: Data concerning clinical attributes and transcriptomic profiles of individuals in the Asian population diagnosed with HCC were retrieved from the TCGA database. Concurrently, immune-related genes were sourced from the Immport database for incorporation into our analysis. A total of 265 immune-related genes displaying differential expression were identified through wilcoxTest analysis in R. Further refinement using univariate and multivariate Cox regression analysis led to the identification of 15 genes that exhibited strong associations with prognosis. MICB/PSMD14/TRAF3/SP1/NDRG1/HDAC1/HRAS/NRAS/SEMA5B/GMFB/ACVR2B/BRD8/MMP12/KITLG/DCK, and a prognostic risk score model was constructed based on the above genes. Results: The findings demonstrated notable differences in survival rates between the low-risk and high-risk groups, as depicted by the Kaplan-Meier (K-M) survival curves (P<0.001). Furthermore, the model's predictive capability was evidenced by receiver operating characteristic (ROC) curves, with area under the curve (AUC) =0.901. Finally, the relationship of the model with each clinical trait and immune cells was assessed by correlation analysis. Conclusions: The prognostic risk score model constructed by immune genes based on the Asian HCC population has certain predictive capacity.

4.
J Cell Mol Med ; 27(23): 3928-3938, 2023 12.
Article in English | MEDLINE | ID: mdl-37799103

ABSTRACT

Major depressive disorder (MDD) is a severe mental disorder associated with high rates of morbidity and mortality. Current first-line pharmacotherapies for MDD are based on enhancement of monoaminergic neurotransmission, but these antidepressants are still insufficient and produce significant side-effects. Consequently, the development of novel antidepressants and therapeutic targets is desired. Engeletin, a natural Smilax glabra rhizomilax derivative, is a compound with proven efficacy in treating ischemic stroke, yet its therapeutic effects and mechanisms for depression remain unexplored. The effects of engeletin were assessed in the forced swimming test (FST) and tail suspension test (TST) in mice. Engeletin was also investigated in the chronic restraint stress (CRS) mouse model of depression with fluoxetine (FLX) as the positive control. Changes in prefrontal cortex (PFC) spine density, synaptic plasticity-linked protein expressions and the brain-derived neurotrophic factor (BDNF)-tyrosine kinase B (TrkB)- mammalian target of rapamycin complex 1 (mTORC1) signalling pathway after chronic stress and engeletin treatment were then investigated. The TrkB and mTORC1 selective inhibitors, ANA-12 and rapamycin, respectively, were utilized to assess the engeletin's antidepressive mechanisms. Our data shows that engeletin exhibited antidepressant-like activity in the FST and TST in mice without affecting locomotor activity. Furthermore, it exhibited efficiency against the depression of CRS model. Moreover, it enhanced the BDNF-TrkB-mTORC1 pathway in the PFC during CRS and altered the reduction in dendritic spine density and levels of synaptic plasticity-linked protein induced by CRS. In conclusion, engeletin has antidepressant activity via activation of the BDNF-TrkB-mTORC1 signalling pathway and upregulation of PFC synaptic plasticity.


Subject(s)
Depressive Disorder, Major , Neuronal Plasticity , Receptor, trkB , Animals , Humans , Mice , Antidepressive Agents/pharmacology , Antidepressive Agents/therapeutic use , Brain-Derived Neurotrophic Factor/drug effects , Brain-Derived Neurotrophic Factor/metabolism , Depressive Disorder, Major/drug therapy , Hippocampus/metabolism , Mammals/metabolism , Mechanistic Target of Rapamycin Complex 1/drug effects , Mechanistic Target of Rapamycin Complex 1/metabolism , Protein-Tyrosine Kinases/metabolism , Stress, Psychological/drug therapy , Stress, Psychological/metabolism , Neuronal Plasticity/drug effects , Receptor, trkB/drug effects , Receptor, trkB/metabolism
5.
BMC Genomics ; 24(1): 357, 2023 Jun 27.
Article in English | MEDLINE | ID: mdl-37370041

ABSTRACT

BACKGROUND AND OBJECTIVE: Hepatocellular carcinoma (HCC), which has a complex pathogenesis and poor prognosis, is one of the most common malignancies worldwide. Hepatitis virus B infection is the most common cause of HCC in Asian patients. Autophagy is the process of digestion and degradation, and studies have shown that autophagy-associated effects are closely related to the development of HCC. In this study, we aimed to construct a prognostic model based on autophagy-related genes (ARGs) for the Asian HCC population to provide new ideas for the clinical management of HCC in the Asian population. METHODS: The clinical information and transcriptome data of Asian patients with HCC were downloaded from The Cancer Genome Atlas (TCGA) database, and 206 ARGs were downloaded from the human autophagy database (HADB). We performed differential and Cox regression analyses to construct a risk score model. The accuracy of the model was validated by using the Kaplan-Meier (K-M) survival curve, receiver operating characteristic (ROC) curve, and univariate and multivariate Cox independent prognostic analyses. The results Thirteen ARGs that were significantly associated with prognosis were finally identified by univariate and multivariate Cox regression analyses. The K-M survival curves showed that the survival rate of the low-risk group was significantly higher than that of the high-risk group (p < 0.001), and the multi-indicator ROC curves further demonstrated the predictive ability of the model (AUC = 0.877). CONCLUSION: The risk score model based on ARGs was effective in predicting the prognosis of Asian patients with HCC.


Subject(s)
Carcinoma, Hepatocellular , Liver Neoplasms , Humans , Asian , Autophagy/genetics , Carcinoma, Hepatocellular/genetics , Liver Neoplasms/genetics , Prognosis
6.
Int J Biol Markers ; 38(1): 37-45, 2023 Mar.
Article in English | MEDLINE | ID: mdl-36377344

ABSTRACT

OBJECTIVES: Non-small cell lung cancer (NSCLC) is a leading type of lung cancer with a high mortality rate worldwide. Although many procedures for the diagnosis and prognosis assessment of lung cancer exist, they are often laborious, expensive, and invasive. This study aimed to develop an ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS)-based analysis method for the plasma biomarkers of NSCLC with the potential to indicate the stages and progression of this malignancy conveniently and reliably. METHODS: A total of 53 patients with NSCLC in early stages (I-III) and advanced stage (IV) were classified into the early and advanced groups based on the tumor node metastasis staging system. A comprehensive metabolomic analysis of plasma from patients with NSCLC was performed via UPLC-MS/MS. Principal component analysis and partial least squares-discriminant analysis were conducted for statistical analysis. Potential biomarkers were evaluated and screened through receiver operating characteristic analyses and correlation analysis. Main differential metabolic pathways were also identified by utilizing metaboanalyst. RESULTS: A total of 129 differential metabolites were detected in accordance with the criteria of VIP ≥ 1 and a P-value of ≤ 0.05. The receiver operating characteristic curves indicated that 11 of these metabolites have the potential to be promising markers of disease progression. Apparent correlated metabolites were also filtered out. Furthermore, the 11 most predominant metabolic pathways with alterations involved in NSCLC were identified. CONCLUSION: Our study focused on the plasma metabolomic changes in patients with NSCLC. These changes may be used for the prediction of the stage and progression of NSCLC. Moreover, we discussed the metabolic pathways wherein the altered metabolites were mainly enriched.


Subject(s)
Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Humans , Carcinoma, Non-Small-Cell Lung/pathology , Lung Neoplasms/diagnosis , Chromatography, Liquid , Tandem Mass Spectrometry , Biomarkers
7.
Mol Psychiatry ; 27(12): 5195-5205, 2022 12.
Article in English | MEDLINE | ID: mdl-36065016

ABSTRACT

Antipsychotic-induced metabolic syndrome (APs-induced Mets) is the most common adverse drug reaction, which affects more than 60% of the psychiatric patients. Although the etiology of APs-induced Mets has been extensively investigated, there is a lack of integrated analysis of the genetic and epigenetic factors. In this study, we performed genome-wide, whole-exome sequencing (WES) and epigenome-wide association studies in schizophrenia (SCZ) patients with or without APs-induced Mets to find the underlying mechanisms, followed by in vitro and in vivo functional validations. By population-based omics analysis, we revealed that rare functional variants across in the leptin and peroxisome proliferator-activated receptors (PPARs) gene sets were imbalanced with rare functional variants across the APs-induced Mets and Non-Mets cohort. Besides, we discovered that APs-induced Mets are hypermethylated in ABCG1 (chr21:43642166-43642366, adjusted P < 0.05) than Non-Mets, and hypermethylation of this area was associated with higher TC (total cholesterol) and TG (triglycerides) levels in HepG2 cells. Candidate genes from omics studies were furtherly screened in C. elegans and 17 gene have been verified to associated with olanzapine (OLA) induced fat deposit. Among them, several genes were expressed differentially in Mets cohort and APs-induced in vitro/in vivo models compared to controls, demonstrating the validity of omics study. Overexpression one of the most significant gene, PTPN11, exhibited compromised glucose responses and insulin resistance. Pharmacologic inhibition of PTPN11 protected HepG2 cell from APs-induced insulin resistance. These findings provide important insights into our understanding of the mechanism of the APs-induced Mets.


Subject(s)
Antipsychotic Agents , Leptin , Metabolic Syndrome , Peroxisome Proliferator-Activated Receptors , Animals , Humans , Antipsychotic Agents/adverse effects , ATP Binding Cassette Transporter, Subfamily G, Member 1/genetics , Caenorhabditis elegans , Insulin Resistance/genetics , Leptin/genetics , Metabolic Syndrome/chemically induced , Metabolic Syndrome/complications , Metabolic Syndrome/genetics , Multiomics , Peroxisome Proliferator-Activated Receptors/genetics
8.
J Endourol ; 36(9): 1199-1205, 2022 09.
Article in English | MEDLINE | ID: mdl-35509258

ABSTRACT

Background: In traditional laparoscopic orchiopexy for inguinal undescended testis (UDT) surgery, the testicles are pulled back into the abdominal cavity by grasping and cephalad retracting the testicle and the cord. If this fails, a subsequent open inguinal incision is made to complete orchiopexy. To improve the orchiolysis and avoid extra open inguinal incision, we describe our early experience with and illustrate the surgical procedure of a novel anatomical laparoscopic orchiopexy (ALO) and hybrid transscrotal orchiopexy as required in high palpable UDT. Methods: From March 2018 to April 2020, ALO was performed in 140 consecutive patients (158 testes) with high inguinal UDT. After blunt and bloodless dissection of the inter-tunica vaginalis-cremasteric fascia plane, tunica vaginalis enveloping the testis was brought into the abdominal cavity as a whole. When the tunica vaginalis was unable to be brought into the abdominal cavity, given that the orchiolysis had already been partially carried out, the testis could be brought out of the external ring and descended when converting to transscrotal surgery. Results: The mean age in this study was 1.88 years (standard deviation ±1.95). The position of the testis assessed at surgery was peeping (58, 36.7%) and canalicular (100, 63.3%). In 128 testes (81.1%), ALO brought the UDT into the abdominal cavity; the remaining 30 testes (18.9%) required a hybrid transscrotal technique. All testes were descended without conversion to open inguinal procedure. The mean operative time was 43.9 ± 9.2 minutes. All patients had follow-up within a median of 17.8 months, with satisfactory results in relation to viability and location of the testis. Conclusions: ALO was shown to be not only safe, feasible, and effective for high inguinal UDT but also facilitated subsequent hybrid transscrotal orchiopexy; when the testis failed to be pulled into the abdominal cavity, the conversion to open inguinal orchiopexy could be obviated.


Subject(s)
Abdominal Cavity , Cryptorchidism , Laparoscopy , Abdominal Cavity/surgery , Cryptorchidism/surgery , Humans , Infant , Laparoscopy/methods , Male , Orchiopexy/methods , Testis/surgery , Treatment Outcome
9.
Hereditas ; 158(1): 48, 2021 Dec 18.
Article in English | MEDLINE | ID: mdl-34922634

ABSTRACT

BACKGROUND: Indian Hedgehog (IHH), an important cell signaling protein, plays a key regulatory role in development of cartilage and chondrogenesis. Earlier studies have shown that heterozygous missense mutations in IHH gene may cause brachydactyly type A1 (BDA1), an autosomal dominant inheritance disease characterized by apparent shortness or absence of the middle phalanges of all digits. MicroRNAs (miRNAs) have been found to be significant post-transcriptional regulators of gene expression and significantly influence the process of bone-development. Therefore, it is possible that miRNAs are involved in the mechanism underlying the development of BDA1. However, the relationship between miRNAs and the pathogenesis of BDA1 remains unclear. METHODS: In this study, we used microarray-based miRNA profiling to investigate the role of miRNAs in BDA1 by characterization of differentially expressed miRNAs in C3H10T1/2 cell line induced by wild type (WT) and p.E95K mutant (MT) IHH signaling. RESULTS: Our results identified 6 differentially expressed miRNAs between WT and control (CT) group and 5 differentially expressed miRNAs between MT and CT groups. In particular, miR-135a-1-3p was found to be a significantly differentially expressed miRNA between WT and CT group. Results of dual-luciferase reporter gene experiment successfully discovered Hoxd10 was one of the target gene of miR-135a-1-3p. Additionally, our pathway analysis revealed that the targets of these miRNAs of interest were highly involved with Runx1/2, Notch and collagen-related pathways. CONCLUSIONS: Taken together, our findings provided important clue for future study of the process of miRNA-regulation in IHH signaling and novel insights into the regulatory role of miRNA in pathogenesis of BDA1.


Subject(s)
Brachydactyly , Hedgehog Proteins , MicroRNAs , Animals , Cell Line , Gene Expression Profiling , Hedgehog Proteins/genetics , Heterozygote , Mice , MicroRNAs/genetics , Signal Transduction
10.
Int J Mol Sci ; 22(23)2021 Nov 26.
Article in English | MEDLINE | ID: mdl-34884615

ABSTRACT

Human cytochrome P450 (CYP) enzymes, as membrane-bound hemoproteins, play important roles in the detoxification of drugs, cellular metabolism, and homeostasis. In humans, almost 80% of oxidative metabolism and approximately 50% of the overall elimination of common clinical drugs can be attributed to one or more of the various CYPs, from the CYP families 1-3. In addition to the basic metabolic effects for elimination, CYPs are also capable of affecting drug responses by influencing drug action, safety, bioavailability, and drug resistance through metabolism, in both metabolic organs and local sites of action. Structures of CYPs have recently provided new insights into both understanding the mechanisms of drug metabolism and exploiting CYPs as drug targets. Genetic polymorphisms and epigenetic changes in CYP genes and environmental factors may be responsible for interethnic and interindividual variations in the therapeutic efficacy of drugs. In this review, we summarize and highlight the structural knowledge about CYPs and the major CYPs in drug metabolism. Additionally, genetic and epigenetic factors, as well as several intrinsic and extrinsic factors that contribute to interindividual variation in drug response are also reviewed, to reveal the multifarious and important roles of CYP-mediated metabolism and elimination in drug therapy.


Subject(s)
Cytochrome P-450 Enzyme System/metabolism , Inactivation, Metabolic , Pharmaceutical Preparations/metabolism , Xenobiotics/metabolism , Animals , Cytochrome P-450 Enzyme System/genetics , Humans , Metabolic Clearance Rate , Polymorphism, Genetic
11.
Medicine (Baltimore) ; 100(29): e26202, 2021 Jul 23.
Article in English | MEDLINE | ID: mdl-34397999

ABSTRACT

INTRODUCTION: Previous research indicates that the platelet-to-lymphocyte ratio (PLR) may be an indicator of poor prognosis in many tumor types. However, the PLR is rarely described in patients undergoing neoadjuvant chemotherapy (NAC) for solid tumors. Thus, we performed a meta-analysis to investigate the prognostic value of this ratio for patients with solid tumors treated by NAC. METHODS: A comprehensive search of the literature was conducted using the PubMed, EMBASE, Cochrane Library, and Web of Science databases, followed by a manual search of references from the retrieved articles. Pooled hazard ratios (HRs) with 95% confidence interval (CIs) were used to evaluate the association between PLR and 3 outcomes, namely, overall survival, disease-free survival, and pathological complete response rate after NAC. RESULTS: Eighteen studies published no earlier than 2014 were included in our study. A lower PLR was associated with better overall survival (HR = 1.46, 95% CI, 1.11-1.92) and favorable disease-free survival (HR = 1.81, 95% CI, 1.27-2.59). A PLR that was higher than a certain cutoff was associated with a lower pathological complete response rate in patients with cancer who received NAC (Odds ratio = 1.93, 95% CI, 1.40-2.87). CONCLUSION: Elevated PLR is associated with poor prognosis in various solid tumors. PLR may be a useful biomarker in delineating those patients with poorer prognoses who may benefit from neoadjuvant therapies.


Subject(s)
Lymphocyte Count/standards , Neoadjuvant Therapy/methods , Neoplasms/pathology , Platelet Count/standards , Prognosis , Blood Platelets/classification , Blood Platelets/pathology , Humans , Lymphocyte Count/methods , Lymphocytes/classification , Lymphocytes/pathology , Neoplasms/physiopathology , Neoplasms/therapy , Platelet Count/methods
12.
Int J Mol Sci ; 20(17)2019 Aug 27.
Article in English | MEDLINE | ID: mdl-31461846

ABSTRACT

Affinity maturation and rational design have a raised importance in the application of nanobody (VHH), and its unique structure guaranteed these processes quickly done in vitro. An anti-CD47 nanobody, Nb02, was screened via a synthetic phage display library with 278 nM of KD value. In this study, a new strategy based on homology modeling and Rational Mutation Hotspots Design Protocol (RMHDP) was presented for building a fast and efficient platform for nanobody affinity maturation. A three-dimensional analytical structural model of Nb02 was constructed and then docked with the antigen, the CD47 extracellular domain (CD47ext). Mutants with high binding affinity are predicted by the scoring of nanobody-antigen complexes based on molecular dynamics trajectories and simulation. Ultimately, an improved mutant with an 87.4-fold affinity (3.2 nM) and 7.36 °C higher thermal stability was obtained. These findings might contribute to computational affinity maturation of nanobodies via homology modeling using the recent advancements in computational power. The add-in of aromatic residues which formed aromatic-aromatic interaction plays a pivotal role in affinity and thermostability improvement. In a word, the methods used in this study might provide a reference for rapid and efficient in vitro affinity maturation of nanobodies.


Subject(s)
Antibody Affinity , CD47 Antigen/chemistry , Molecular Docking Simulation , Single-Chain Antibodies/chemistry , Binding Sites, Antibody , CD47 Antigen/genetics , CD47 Antigen/immunology , Humans , Mutation , Single-Chain Antibodies/genetics , Single-Chain Antibodies/immunology
13.
ChemSusChem ; 12(4): 795-800, 2019 Feb 21.
Article in English | MEDLINE | ID: mdl-30628203

ABSTRACT

Two-dimensional tungsten sulfide is widely applied in electrocatalysis. However, WS2 possesses catalytic active sites located at the layer edge and an inert surface for catalysis. Therefore, increasing the exposure of active sites at the edge and effectively activating the inert sites on the surface is an important challenge. Here, an edge/defect-rich and oxygen-heteroatom-doped WS2 (ED-O-WS2 ) superstructure was synthesized. The power-conversion efficiency (PCE) of dye-sensitized solar cells (DSCs) based on an ED-O-WS2 counter electrode reached 10.36 % (under 1 sun, AM 1.5, 100 mW cm-2 ) and 11.19 % (under 40 mW cm-2 ). These values are, to our knowledge, the highest reported efficiency for DSCs based on Pt-free counter electrodes in I3 - /I- electrolytes. Analysis of the micro/nano structure and the electrocatalytic mechanism indicate that ED-O-WS2 exhibits metallic properties in the electrolyte, and that abundant edges and defects as well as oxygen doping in ED-O-WS2 play an important role in improving the catalytic activity of WS2 . Moreover, ED-O-WS2 displays better catalytic reversibility for I3 - /I- electrolytes than Pt.

14.
R Soc Open Sci ; 5(8): 180897, 2018 Aug.
Article in English | MEDLINE | ID: mdl-30225079

ABSTRACT

Resulting from the drastic increase of atmospheric CO2 concentration day by day, global warming has become a serious environmental issue nowadays. The fixation of CO2 to obtain desirable, economically competitive chemicals has recently received considerable attention. This work investigates the fixation of CO2 along with three bromopyridines via a facile electrochemical method using a silver cathode to synthesize picolinic acids, which are important industrial and fine chemicals. Cyclic voltammetry is employed to investigate the cyclic voltammetric behaviour of bromopyridines. In addition, systematic study is conducted to study the relationships between the picolinic acids' yield and the electrolysis conditions and intrinsic parameters. The results show that the target picolinic acids' yields are strongly dependent on various conditions such as solvent, supporting electrolyte, current density, cathode material, charge passed, temperature and the nature of the substrates. Moreover, in the studied electrode materials such as Ag, Ni, Ti, Pt and GC, electrolysis and cyclic voltammetry show that Ag has a good electrocatalytic effect on the reduction and carboxylation of bromopyridine. This facile electrochemical route for fixation of CO2 provides an indispensable reference for the conversion and utilization of CO2 under mild conditions.

15.
ACS Omega ; 3(10): 14021-14026, 2018 Oct 31.
Article in English | MEDLINE | ID: mdl-31458097

ABSTRACT

In this study, all-inorganic copper halide salt K2Cu2Cl6 single-crystal and thin films were prepared. The single-crystal diffraction data belonged to the monoclinic K2Cu2Cl6 (space group = P 2(1)/C, unit cell parameters of a = 4.0340 Å, b = 13.7987 Å, c = 8.7445 Å, α = 90.000, ß = 97.123, and γ = 90.000). As far as we know, this is the first study of the copper halide salt K2Cu2Cl6 for optoelectronic applications. The band gap of K2Cu2Cl6 is calculated to be approximately 1.85 eV. A low-cost photodetector based on the K2Cu2Cl6 thin film was efficient under different monochromatic light from 330 to 390 nm with different chopping frequencies (1.33-30 Hz). Density functional theory (DFT) computational results indicate that the valence bands (VBs) and conduction bands (CBs) are shifted up in energy using the orbital-dependent correction to the DFT energy. Partial density of states reveals that the VBs and narrow CBs are derived from the hybrid orbitals of Cu2+ 3d and Cl- p, respectively.

16.
RSC Adv ; 8(51): 29089-29095, 2018 Aug 14.
Article in English | MEDLINE | ID: mdl-35548024

ABSTRACT

All-inorganic lead halide perovskite CsPbBr3 has important applications in photoelectronic devices such as photodetectors, LEDs and photovoltaic devices. However, preparing high-quality CsPbBr3 thin films has proven to be challenging. In this study, we prepared all-inorganic lead halide perovskite CsPbBr3 thin films with micron-grains (MG-CsPbBr3-TF) via a heat-spraying process (HSP) using a CsPbBr3-saturated solution (CsPbBr3-SS), and the films exhibited large area, low defects and high stability. The grain size of MG-CsPbBr3-TF was about 1-5 microns. The micron-sized grains in MG-CsPbBr3-TF enabled the absorption cutoff edge to be extended from 537 to 545 nm. In addition, the presence of fewer boundaries in MG-CsPbBr3-TF reduced the defects in MG-CsPbBr3-TF (the blue shift of luminescence). The response wavelengths of a low-cost and self-driven (zero-biased) photodetector based on MG-CsPbBr3-TF were from 330 to 600 nm. CsPbBr3 thin films having a large area (10 cm × 10 cm) and micron-sized grains were also prepared by HSP and exhibited excellent stability (1944 h) in air (T = 298 K, 40% humidity). To the best of our knowledge, this is the first study of high-quality CsPbBr3 thin films prepared by HSP. The results are of great interest for both fundamental research and practical applications of CsPbBr3 in photodetectors, LEDs and photovoltaic devices.

17.
Soft Matter ; 13(6): 1171-1181, 2017 Feb 08.
Article in English | MEDLINE | ID: mdl-28098305

ABSTRACT

The phase behaviour of a ternary system composed of cationic gemini surfactant 2-hydroxypropyl-1,3-bis(myristyldimethylammonium chloride) (14-3(OH)-14(2Cl)), nonionic surfactant polyoxyethylene laurel ether (C12H25(OCH2CH2)10OH, Brij-30) and H2O was studied and its phase diagram was determined. In several different phase regions identified in the phase diagram, the viscoelastic worm-like micellar solution region was investigated. The focus of the investigation was the increase in the viscosity of the micellar solution with the temperature and the Brij-30 content, as suggested by a partial region of the triangular phase diagram. With an increase in the Brij-30 content or temperature, one-dimensional micellar growth occurred, and a maximum appeared in the zero-shear viscosity, η0, versus Brij-30 content or temperature curves; this was true for mixed solutions containing 14-3(OH)-14(2Cl) and Brij-30 in different mass ratios (WBrij-30/W14-3(OH)-14(2Cl)). After the maximum point, the decrease in viscosity is the result of the micellar shortening in the size with Brij-30 content and of the micellar branching in the network structure with temperature. This rheological analysis was performed to investigate the structural changes in different solutions as well as the effects of various factors on micellar growth. Various techniques were used to study the phase-transition processes occurring in this system, including cryogenic transmission electron microscopy, small-angle X-ray scattering measurements, and differential scanning calorimetry. The transition mechanisms of the aggregates were analysed on the basis of the obtained results.

18.
R Soc Open Sci ; 4(12): 171409, 2017 Dec.
Article in English | MEDLINE | ID: mdl-29308262

ABSTRACT

Three-dimensional (3D) graphene composites have drawn increasing attention in energy storage/conversion applications due to their unique structures and properties. Herein, we synthesized 3D honeycomb-like Ni3S2@graphene oxide composite (3D honeycomb-like Ni3S2@GO) by a one-pot hydrothermal method. We found that positive charges of Ni2+ and negative charges of NO3- in Ni(NO3)2 induced a transformation of graphene oxide with smooth surface into graphene oxide with wrinkled surface (w-GO). The w-GO in the mixing solution of Ni(NO3)2/thioacetamide/H2O evolved into 3D honeycomb-like Ni3S2@GO in solvothermal process. The GO effectively inhibited the aggregation of Ni3S2 nanoparticles. Photoelectrochemical cells based on 3D Ni3S2@GO synthesized at 60 mM l-1 Ni(NO3)2 exhibited the best energy conversion efficiency. 3D Ni3S2@GO had smaller charge transfer resistance and larger exchange current density than pure Ni3S2 for iodine reduction reaction. The cyclic stability of 3D honeycomb-like Ni3S2@GO was good in the iodine electrolyte. Results are of great interest for fundamental research and practical applications of 3D GO and its composites in solar water-splitting, artificial photoelectrochemical cells, electrocatalysts and Li-S or Na-S batteries.

19.
ACS Appl Mater Interfaces ; 8(41): 28187-28193, 2016 Oct 19.
Article in English | MEDLINE | ID: mdl-27686006

ABSTRACT

Organic-inorganic lead perovskite materials show impressive performance in photovoltaics, photodetectors, light-emitting diodes, lasers, sensors, medical imaging devices, and other applications. Although organic-inorganic lead perovskites have shown good performance in numerous fields, they contain toxic Pb, which is expected to cause environmental pollution in future large-scale applications. Thus, the photoelectric properties of Pb-free organic-inorganic perovskite materials should be developed and studied. In this paper, we report on the photoresponse of Pb-free organic-inorganic hybrid manganese perovskite (CH3NH3)2MnCl4. To the best of our knowledge, this study demonstrates the first time that organic-inorganic hybrid manganese perovskites are used for this type of application. We found that the solution-processed MA2MnCl4 thin film tends to be oriented along the b-axis direction on the TiO2 surface. The evident photoresponse of the FTO/TiO2/MA2MnCl4/carbon electrode devices was observed under 10-30 Hz flashlight frequencies and a 330 nm light beam. This simple, green, and low-cost photoresponsive device is beneficial for the future industrial production of optical recorders and optical memory devices.

20.
ACS Appl Mater Interfaces ; 8(8): 5314-9, 2016 Mar 02.
Article in English | MEDLINE | ID: mdl-26838272

ABSTRACT

The scarcity and noble indium and platinum (Pt) are important elements in photoelectric nanomaterials. Therefore, development of low cost alternative materials to meet different practical applications is an urgent need. Two-dimensional (2D) layered graphene (GE) with unique physical, mechanical, and electrical properties has recently drawn a great deal of attention in various optoelectronic fields. Herein, the large scale (21 cm × 15 cm) high-quality single layer graphene (SLG) and multilayer graphene on a flexible plastic substrate PET were controllably prepared through layer-by-layer (LBL) transfer using the thermal release adhesive transfer method (TRA-TM). Transmission and antibending performance based on PET/GE were superior to traditional PET/ITO. The square resistance of a nine-layer graphene electrode reached approximately 58 Ω. Combined with our newly developed and highly effective Fe3O4@RGO (reduced graphene oxide) catalyst, the power conversion efficiency of the dye-sensitized solar cell (DSC) using flexible PET/GE conductive substrate was comparable to that of the DSC using the PET/ITO substrate. The desirable performance of PET/GE/Fe3O4@RGO counter electrodes (low-cost indium- and platinum-free counter electrodes) is attributed to the interfacial compatibility between 2D graphene composite catalyst (Fe3O4@RGO) and 2D PET/GE conductive substrate. In addition, DSCs that use only PET/GE (without Fe3O4@RGO catalyst) as counter electrodes can also achieve a photocurrent density of 6.30 mA cm(-2). This work is beneficial for fundamental research and practical applications of graphene and graphene composite in photovoltaics, photocatalytic water splitting, supercapacitors.

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