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1.
DNA Cell Biol ; 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38829105

RESUMEN

This study aimed to determine the function of angiopoietin-related protein 4 (ANGPTL4) and bone morphogenetic protein 7 (BMP7) on hepatocellular carcinoma (HCC). Overexpressing plasmids were cotransfected into HepG2 cells to determine the interaction between ANGPTL4 and BMP7. The effect of ANGPTL4 on the stability of BMP7 is examined by detecting the expression and ubiquitination levels. In vitro and in vivo experiments of knocking down ANGPTL4 while overexpressing BMP7 were performed to investigate whether the effects of ANGPTL4 on HCC proliferation, migration, and downstream signaling pathways were dependent on BMP7. ANGPTL4 is able to interact with BMP7, and knockdown of ANGPTL4 increased BMP7 expression and ubiquitination. Overexpression of BMP7 reversed the inhibition of HCC proliferation and migration as well as the decrease in the expression levels of Smad1/5/8 and MAPK14 caused by knockdown of ANGPTL4. ANGPTL4 promotes the proliferation and migration of HCC by inhibiting the ubiquitination degradation of BMP7 and the Smad/MAPK pathway, providing a novel mechanism and a potential therapeutic target for the treatment of HCC.

2.
DNA Cell Biol ; 43(4): 175-184, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38466955

RESUMEN

To investigate the functional differences of angiopoietin-related protein 4 (ANGPTL4) transcripts in hepatocellular carcinoma (HCC) cells. By transfecting ANGPTL4-Transcript 1 and ANGPTL4-Transcript 3 overexpression vectors into HepG2 and Huh7 cell lines with ANGPTL4 knockdown, the effects of overexpression of two transcripts on cell viability, invasion, migration, and apoptosis were analyzed. The expression of two transcripts was compared in human liver cancer tissue, and their effects on tumor development were validated in vivo experiments in mice. Compared with control, the overexpression of ANGPTL4-Transcript 1 had no significant effect on viability, invasion, healing, and apoptosis of HepG2 and Huh7 cells. However, these two cell lines overexpressing ANGPTL4-Transcript 3 showed remarkably enhanced cell viability, invasive and healing ability, and decreased apoptosis ability. Furthermore, the mRNA level of ANGPTL4-Transcript 3 was significantly increased in human HCC tissues and promoted tumor growth compared with Transcript 1. Different transcripts of gene ANGPTL4 have distinct effects on HCC. The abnormally elevated Transcript 3 with the specific ability of promoting HCC proliferation, infiltration, and migration is expected to become a new biological marker and more precise intervention target for HCC.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Animales , Ratones , Neoplasias Hepáticas/patología , Carcinoma Hepatocelular/patología , Proteína 4 Similar a la Angiopoyetina/genética , Proteína 4 Similar a la Angiopoyetina/metabolismo , Línea Celular Tumoral , Movimiento Celular/genética , Apoptosis/genética , Proliferación Celular/genética , Regulación Neoplásica de la Expresión Génica
3.
Dalton Trans ; 53(11): 5051-5063, 2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38375864

RESUMEN

The accurate and rapid detection of antibiotics and heavy-metal-based toxic oxo-anions in water media employing coordination polymers (CPs) as luminescent probes has attracted a lot of attention. Three new Cd(II)-based ternary CPs derived from first-presented L ligands, including [Cd(DCTP)(L)(OH)]n (1), [Cd(TBTA)(L)(OH)]n (2), and [Cd(NPHT)(L)(H2O)]n (3) (L = 2-((1H-imidazol-1-yl)methyl)-5,6-dimethyl-1H-benzo[d]imidazole, H2DCTP = 2,5-dichloroterephthalic acid, H2TBTA = tetrabromoterephthalic acid and H2NPHT = 3-nitrophthalic acid), were successfully assembled and characterized. 1 and 2 show 2D hcb layers, which can be further extended into a 3D supramolecular framework via classic hydrogen bonding interactions. 3 features a 1D double chain that ultimately spreads into a 2D network through weak hydrogen bonding interactions. With the advantages of high stability and excellent luminescent properties, the three CPs display high sensitivity, selectivity, and good anti-interference for the sensing of pefloxacin (PEF) and Cr2O72- ions (LOD values toward PEF: 3.82 × 10-7 mol L-1 for 1, 4.06 × 10-7 mol L-1 for 2, and 1.36 × 10-8 mol L-1 for 3, and toward Cr2O72- ions: 5.97 × 10-7 mol L-1 for 1, 5.87 × 10-7 mol L-1 for 2, and 8.21 × 10-8 mol L-1 for 3). These CPs are the first examples of bifunctional luminescent sensors to detect PEF and Cr2O72- in aqueous solutions. The luminescence quenching mechanisms are explored in detail.

4.
Discov Med ; 36(180): 173-181, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38273757

RESUMEN

BACKGROUND: Hepatocellular carcinoma (HCC) is a malignant tumor that impacts individuals worldwide and is particularly prevalent in Asia. Angiopoietin-like protein 4 (ANGPTL4) plays an important role in regulating glucose and lipid metabolism in mouse liver. We sought to explore the effects of the ANGPTL4 gene on cell viability, migration, invasive capacity, and apoptosis of HCC cells. METHODS: The expression of ANGPTL4 in HCC and paracancerous tissues was determined by immunohistochemistry and immunofluorescence assays. The ANGPTL4 knockdown cells were established by shRNA transfection. The effect of ANGPTL4 knockdown on HepG2 and Huh7 cells was determined by Cell Count Kit-8 (CCK-8), wound healing and transwell assays. Cell apoptosis was determined by flow cytometry. RESULTS: The ANGPTL4 expression was dramatically enhanced in HCC tissues than in paracancerous tissues (p < 0.001). HCC cell lines HepG2 and Huh7 with knockdown of ANGPTL4 gene showed lower cell viability, migration, and invasion ability while inducing higher apoptosis levels than the control group (p < 0.001). CONCLUSIONS: High expression of ANGPTL4 is closely related to HCC. Knockdown of ANGPTL4 significantly inhibits the proliferation of HCC cells. This study provides a rationale for the ANGPTL4 gene, a molecular marker of HCC.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animales , Ratones , Carcinoma Hepatocelular/patología , Neoplasias Hepáticas/patología , Proteína 4 Similar a la Angiopoyetina/genética , Proteína 4 Similar a la Angiopoyetina/metabolismo , Línea Celular Tumoral , Apoptosis/genética , Proliferación Celular/genética , Movimiento Celular/genética , Regulación Neoplásica de la Expresión Génica
5.
Oncol Lett ; 26(3): 388, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37559583

RESUMEN

The utilization of immune checkpoint inhibitors in oncological treatment has increased in recent years. The therapeutic strategy of targeting the programmed death-1 (PD-1)/programmed death-ligand 1 (PD-L1) pathway has altered the management of advanced non-small cell lung carcinoma (NSCLC). Tislelizumab, a novel anti-PD-1 monoclonal antibody developed in China, has demonstrated efficacy in treating advanced NSCLC. However, its potential role as a neoadjuvant therapy for locally advanced NSCLC has not been definitively established. Current guidelines do not specify which patient populations may gain the most benefit from neoadjuvant immunotherapy coupled with chemotherapy, nor do they indicate the optimal timing, dose or duration of adjuvant maintenance therapy post-NSCLC surgery. Similarly, data concerning the safety and practicability of surgical resection following neoadjuvant tislelizumab treatment for NSCLC remain limited. The present study describes the case of a patient diagnosed with stage IIIB NSCLC, which was initially deemed unresectable. A preoperative biopsy of the tumor mass revealed squamous cell carcinoma and a negative PD-L1 gene test. Notably, after two cycles of neoadjuvant tislelizumab treatment coupled with chemotherapy, the tumor exhibited marked shrinkage. This permitted the patient to undergo thoracoscopic radical lung cancer resection, which resulted in a pathological complete response. Postoperative pathology identified a large infiltration of lymphoplasmacytic cells and foamy histiocytes. The patient experienced grade 2 myelosuppression, a condition that was successfully addressed with the administration of recombinant human granulocyte colony-stimulating factor. The present case indicates the safety and feasibility of neoadjuvant immunotherapy integrated with chemotherapy for patients with locally advanced, PD-L1-negative NSCLC prior to surgical intervention. Moreover, the case suggests the potential of this therapeutic combination to alter the tumor microenvironment. However, the generalization of these findings necessitates further validation through randomized multicenter trials.

6.
Cancer Genet ; 268-269: 37-45, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36152512

RESUMEN

BACKGROUND: The aim of this paper is to explore the correlation between circulating tumor DNA (ctDNA) methylation and mutations and its value in clinical early cancer screening. METHODS: We performed target region methylation sequencing and genome sequencing on plasma samples. Methylation models to distinguish cancer from healthy individuals have been developed using hypermethylated genes in tumors and validated in training set and prediction set. RESULTS: We found that patients with cancer had higher levels of ctDNA methylation compared to healthy individuals. The level of ctDNA methylation in cell cycle, p53, Notch pathway in pan-cancer was significantly correlated with the number of mutations, and mutation frequency. Methylation burden in some tumors was significantly correlated with tumor mutational burden (TMB), microsatellite instability (MSI) and PD-L1. The ctDNA methylation differences in cancer patients were mainly concentrated in the Herpes simplex virus 1 infection pathway. The area under curve (AUC) of the training and prediction sets of the methylation model distinguishing cancer from healthy individuals were 0.93 and 0.92, respectively. CONCLUSION: Our study provides a landscape of methylation levels of important pathways in pan-cancer. ctDNA methylation significantly correlates with mutation type, frequency and number, providing a reference for clinical application of ctDNA methylation in early cancer screening.


Asunto(s)
ADN Tumoral Circulante , Neoplasias , Humanos , ADN Tumoral Circulante/genética , Metilación , Neoplasias/genética , Biomarcadores de Tumor/genética , Mutación
7.
Dis Markers ; 2022: 1844352, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35692877

RESUMEN

Background: Hepatocellular carcinoma (HCC) is highly aggressive with a poor prognosis and survival rate. Certain ANGPTL members have been implicated in tumor progression. However, the relevance of the ANGPTL gene family to HCC remains poorly understood. In this study, we explored the role of ANGPTLs in the prognosis of HCC. Methods: From the CCLE database, we studied the expression of ANGPTLs in a range of cancer cell lines. The UCSC, HCCDB, and Human Protein Atlas databases were used to analyze the differences in mRNA and protein expression of ANGPTLs in HCC tissues. Additionally, the correlation between ANGPTL mRNA and methylation levels and clinicopathological features were assessed in the TCGA database. The correlation between ANGPTL mRNA and overall survival was determined by the Kaplan-Meier plotter. cBioPortal database was used to analyze ANGPTL genomic alterations. Genes associated with ANGPTLs were determined by enrichment with KEGG. Moreover, the differentially expressed genes of ANGPTLs were analyzed by the LinkedOmics database, and the KEGG pathway and miRNA targets of ANGPTLs were also enriched. Results: There was a significant correlation between the ANGPTL members (excluding ANGPTL2) and the prognosis of HCC patients according to the Kaplan-Meier plotter analysis (p < 0.05). ANGPTL1 was the gene with the highest mutation frequency. ANGPTLs are involved in certain pathways that may influence the development of HCC. Conclusion: In summary, the expression of some members of ANGPTLs was significantly correlated with HCC prognosis, suggesting that the ANGPTL gene family members may be promising molecular markers for HCC treatment and prognosis.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Proteína 2 Similar a la Angiopoyetina , Proteínas Similares a la Angiopoyetina/genética , Biomarcadores de Tumor/genética , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Familia , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Pronóstico , ARN Mensajero
8.
Anticancer Drugs ; 33(7): 686-690, 2022 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-35324515

RESUMEN

Thymic lymphoepithelioma-like carcinoma (LELC) is a rare primary malignant neoplasm originating from the thymus. Thymic LELC diagnosis is often terminal when diagnosed, some patients have lost the opportunity for surgery. Platinum- and anthracycline-based systemic chemotherapy are the first-line treatment plan; however, there is no clear consensus on therapy when first-line treatment fails because of the lack of cases of advanced thymic LELC. Here was a rare case of advanced thymic LELC with bone marrow metastasis at relapse, which is reported in a patient who responded well to toripalimab combined with anlotinib therapy. The treatment showed tolerable toxicity with good antitumor activity in the patient. As far as we know, this is the first case that the combination of toripalimab with anlotinib is effective in controlling advanced thymic LELC with bone marrow metastasis. The case reports represent an essential means by which an effective therapy for advanced thymic LELC may not be practical given the low frequency of a thymic LELC with multiple metastases.


Asunto(s)
Neoplasias de la Médula Ósea , Neoplasias Óseas , Carcinoma de Células Escamosas , Humanos , Inmunoterapia , Platino (Metal)
9.
Dalton Trans ; 50(43): 15743-15753, 2021 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-34700330

RESUMEN

Two luminescent Cd(II)-organic frameworks [Cd2(L1)(tdc)2(H2O)]n (1) and [Cd(L2)0.5(tdc)]n (2) (L1 = 1,5-bis(1-(pyridine-4-ylmethyl)-1H-benzo[d]imidazol-2-yl)pentane, L2 = 1,6-bis(1-(pyridine-4-ylmethyl)-1H-benzo[d]imidazol-2-yl)hexane, and H2tdc = 2,5-thiophenedicarboxylic acid) were hydrothermally synthesized and characterized. 1 displays a rare binodal (3,4)-connected 2D cem-d network, while 2 exhibits a 3D mog (moganite) framework. The two MOFs are highly thermally durable and water-stable in a wide pH range from 3 to 12. Interestingly, 1 and 2 represent the first reported examples of multi-responsive probes based on MOFs for selectively detecting levofloxacin, benzaldehyde, and Fe3+ ions with reusability. The luminescence sensing mechanisms of the two CPs were explored in detail.


Asunto(s)
Cadmio
10.
Front Oncol ; 11: 715541, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34540685

RESUMEN

BACKGROUND: Hepatocellular carcinoma (HCC) is known for its poor prognosis. Long noncoding RNAs (lncRNAs) are critical in the pathogenesis of various types of cancers. We tried to explore the role of lncRNA in the development of HCC. METHODS: We identified the role of lncRNA AC007639.1 in the pathogenesis of HCC through bioinformatics and biological experiments in HepG2, Hep3B, and SMMC-7721 cells as well as the nude mice xenograft model. RESULTS: We found that lncRNA AC007639.1 was overexpressed in hepatocellular carcinoma. Knocking down of lncRNA AC007639.1 by specific siRNAs or shRNAs promoted cancer cell death. The growth of mouse xenograft tumor created using lncRNA AC007639.1 deficient HepG2 cells was significantly slowed down. Furthermore, the knockdown of lncRNA AC007639.1 in HCC cells led to the increased expression of p53 and decreased expression of angiopoietin-like 4. CONCLUSION: LncRNA AC007639.1 was involved in the pathogenesis and progression of hepatocellular carcinoma by inhibition of apoptosis and increasing HCC resistance to chemotherapy.

11.
Dalton Trans ; 50(29): 10180-10186, 2021 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-34231598

RESUMEN

There has been broad attention to the recognition and detection of ions and organic small molecules due to their essential roles in environmental systems. However, dual-functional probes have seldom been developed for sensing organic constituents and lanthanide ions. A new 3D pillared Zn(ii)-organic framework [Zn3(L)(DCTP)3]n (1) (L = 1,4-di(1H-benzo[d]imidazol-2-yl)butane and H2DCTP = 2,5-dichloroterephthalic acid) was hydrothermally synthesized and structurally characterized, and features a unique 3D 4,4,4,6-connected framework containing approximately 9.99 × 9.78 Å2 cubic channels. 1 displays excellent thermal and pH stability and can act as a novel "turn-on" fluorescent probe for highly selectively sensitizing Tb3+ ions through an "antenna effect". Furthermore, 1 is a dual-response fluorescent sensor for monitoring acetylacetone and Tb3+ ions with rapid response times (within 1 min), low limits of detection (LOD) (5.02 × 10-6/1.15 × 10-8 M, separately) and great anti-interference ability and recyclability towards the analytes. The related sensing mechanisms for detecting analytes are also investigated in detail.

12.
Inorg Chem ; 58(23): 15696-15699, 2019 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-31718161

RESUMEN

A cobalt(II) coordination polymer with an unusual 4,4,4-connected network was hydrothermally synthesized and observed with high thermal, solvent, and pH stabilities. This polymer can serve as the first dual-responsive fluorescent chemosensor for the selective detection of acetylacetone and Cr2O72- ion (pH 3.0) in aqueous systems.

13.
Acta Cir Bras ; 34(2): e201900204, 2019 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-30843937

RESUMEN

PURPOSE: To investigate the protective effects of salvianolic acid A (SAA) on renal damage in rats with chronic renal failure (CRF). METHODS: The five-sixth nephrectomy model of CRF was successfully established in group CRF (10 rats) and group CRF+SAA (10 rats). Ten rats were selected as sham-operated group (group S), in which only the capsules of both kidneys were removed. The rats in group CRF+SAA were intragastrically administrated with 10 mg/kg SAA for 8 weeks. The blood urine nitrogen (BUN), urine creatinine (Ucr), creatinine clearance rate (Ccr), and serum uperoxide dismutase (SOD) and malondialdehyde (MDA) were tested. The expressions of transforming growth factor-ß1 (TGF-ß1), bone morphogenetic protein 7 (BMP-7) and Smad6 protein in renal tissue were determined. RESULTS: After treatment, compared with group CRF, in group CRF+SAA the BUN, Scr, serum MDA and kidney/body weight ratio were decreased, the Ccr and serum SOD were increased, the TGF-ß1 protein expression level in renal tissue was decreased, and the BMP-7 and Smad6 protein levels were increased (all P < 0.05). CONCLUSION: SAA can alleviate the renal damage in CRF rats through anti-oxidant stress, down-regulation of TGF-ß1 signaling pathway and up-regulation of BMP-7/Smad6 signaling pathway.


Asunto(s)
Proteína Morfogenética Ósea 7/metabolismo , Ácidos Cafeicos/uso terapéutico , Fallo Renal Crónico/tratamiento farmacológico , Lactatos/uso terapéutico , Proteína smad6/metabolismo , Factor de Crecimiento Transformador beta1/metabolismo , Animales , Modelos Animales de Enfermedad , Regulación hacia Abajo , Fallo Renal Crónico/inducido químicamente , Fallo Renal Crónico/metabolismo , Pruebas de Función Renal , Masculino , Nefrectomía , Ratas , Ratas Sprague-Dawley , Regulación hacia Arriba
14.
Acta cir. bras ; 34(2): e201900204, 2019. tab, graf
Artículo en Inglés | LILACS | ID: biblio-989051

RESUMEN

Abstract Purpose: To investigate the protective effects of salvianolic acid A (SAA) on renal damage in rats with chronic renal failure (CRF). Methods: The five-sixth nephrectomy model of CRF was successfully established in group CRF (10 rats) and group CRF+SAA (10 rats). Ten rats were selected as sham-operated group (group S), in which only the capsules of both kidneys were removed. The rats in group CRF+SAA were intragastrically administrated with 10 mg/kg SAA for 8 weeks. The blood urine nitrogen (BUN), urine creatinine (Ucr), creatinine clearance rate (Ccr), and serum uperoxide dismutase (SOD) and malondialdehyde (MDA) were tested. The expressions of transforming growth factor-β1 (TGF-β1), bone morphogenetic protein 7 (BMP-7) and Smad6 protein in renal tissue were determined. Results: After treatment, compared with group CRF, in group CRF+SAA the BUN, Scr, serum MDA and kidney/body weight ratio were decreased, the Ccr and serum SOD were increased, the TGF-β1 protein expression level in renal tissue was decreased, and the BMP-7 and Smad6 protein levels were increased (all P < 0.05). Conclusion: SAA can alleviate the renal damage in CRF rats through anti-oxidant stress, down-regulation of TGF-β1 signaling pathway and up-regulation of BMP-7/Smad6 signaling pathway.


Asunto(s)
Animales , Masculino , Ratas , Ácidos Cafeicos/uso terapéutico , Proteína smad6/metabolismo , Factor de Crecimiento Transformador beta1/metabolismo , Proteína Morfogenética Ósea 7/metabolismo , Fallo Renal Crónico/tratamiento farmacológico , Lactatos/uso terapéutico , Regulación hacia Abajo , Regulación hacia Arriba , Ratas Sprague-Dawley , Modelos Animales de Enfermedad , Fallo Renal Crónico/inducido químicamente , Fallo Renal Crónico/metabolismo , Pruebas de Función Renal , Nefrectomía
15.
Ultrason Sonochem ; 48: 127-135, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30080535

RESUMEN

Two new Ag(I) coordination polymers (CPs), namely, Ag(L)(Htp) (1) and [Ag(L)]·(Htp)·2H2O (2) were synthesized from the long flexible ligand of 1,6-bis(2-methylbenzimidazolyl)hexane (L), terephthalic acid (H2tp) and different silver(I) salts using hydrothermal and sonochemical methods, These CPs were characterized by elemental analysis, IR spectra, scanning electron microscopy, single-crystal and powder X-ray diffraction analysis. 1 features a uninodal 3-connected 2D hcb layered structure, while 2 exhibits an infinite 1D linear chain and ultimately extended into 3D supramolecular framework via O-H⋯O and Ag⋯O interactions. In addition, the effect of various sonication concentrations of the initial reagents, ultrasonic time and power of ultrasound irradiation on the size and morphology of nanostructured 1 and 2 were evaluated. Nano-sized 1 and 2 exhibit relatively high performance as UV light driven photocatalysts for the degradation of methylene blue.

16.
Dalton Trans ; 46(48): 16911-16924, 2017 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-29171847

RESUMEN

Herein, a nickel coordination polymer (CP 1), {Ni(1,4-bib)1.5(TPA-Cl2)·H2O}n (1,4-bib = 1,4-bis(1H-imidazol-1-yl)benzene, H2TPA-Cl2 = 2,5-dichloro-terephthalic acid), has been synthesized under solvothermal conditions. The structure of CP 1 is a 3D 3-fold interpenetrating framework with the sqc12 topology. The thermal stability and luminescence properties of CP 1 were investigated. Scanning electron microscopy (SEM) images of this material display that it possesses an irregular block 3D structure. Interestingly, CP 1 can serve as a multifunctional material via its luminescence sensing, electrochemical sensing, and photocatalytic properties. The experimental results indicate that CP 1 is an efficient luminescent sensor for the detection of Fe3+ ions in an aqueous solution. In addition, CP 1 exhibits a sensitive and rapid electrochemical response to nitrite ions in water solution. The photocatalytic activities of CP 1 were evaluated in the degradation of different dye contaminants (MB, RhB, and MO), and the results demonstrate that its photocatalytic efficiency for the degradation of MB is highest (92.1% for MB, 85.7% for RhB, and 86.2% for MO). The effects of different dyes, different powers of UV light, and different amounts of catalyst CP 1 on the photocatalytic efficiency were also explored. Finally, the mechanism of the luminescence quenching effect toward Fe3+ ions, electroreduction of nitrite ions, and photocatalytic degradation of different dyes have been investigated in detail.

17.
Ultrason Sonochem ; 39: 837-844, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28733013

RESUMEN

Nanostructures of a new Co(II) coordination polymer (CP), [Co(Hbibp)(nbta)]n (1), (bibp=4,4'-bis(1-imidazolyl)biphenyl, H3nbta=5-nitro-1,2,3-benzenetricarboxylic acid) was synthesized by a sonochemical method. The nano-sized CP 1 was characterized by elemental analysis, IR spectroscopy, X-ray powder diffraction and scanning electron microscopy (SEM). Structural analysis show that CP 1 exhibits a 1D chain structure with a 3-connected SP 1-periodic net (4,4)(0,2) topology, which can be further extended into a 2D supramolecular layer by the NH⋯O hydrogen bond interactions. The thermal stability for CP 1 as bulk and nanoparticles were investigated. The photoluminescence properties and electrochemical behavior for nano-sized CP 1 have also been explored. Moreover, nano-sized CP 1 shows high photocatalytic activities for the degradation of MB under UV irradiation and the photodegradation process is mainly caused by OH radicals. Effects of the sonication time and ultrasonic power on the morphology and size of nanoparticles were studied.

18.
Dalton Trans ; 46(9): 2892-2903, 2017 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-28194471

RESUMEN

The hydrothermal reactions of 1,2,4,5-cyclohexanetetracarboxylic acid (H4L) with CoCl2·2H2O and rigid or semi-rigid bis(imidazole) ligands were able to generate two Co(ii) coordination polymers (CPs), {[Co5(L)2(1,4-bimb)(µ3-OH)2(H2O)8]·2H2O}n (1), {[Co(L)0.5(1,4-bib)]·H2O}n (2) (1,4-bimb = 1,4-bis(imidazol-1-ylmethyl)benzene, 1,4-bib = 1,4-bis(1H-imidazol-1-yl)benzene). CPs 1 and 2 were structurally characterized by elemental analysis, IR spectroscopy, X-ray powder diffraction and single crystal X-ray diffraction. CP 1 features a 3D 3,3,4,4,5-connected framework with an unprecedented {42·8·102·12}{43·6·86}2{43}2{46}2{62·8}2 topology, which represents the first example of CPs with such a topology. CP 2 possesses a three-fold interpenetration 3D framework with mog topology. The distinct structures of the two CPs may result from diverse coordination modes of the (L)4- ligands and different structural characteristics of rigid or semi-rigid N-donor ligands. The thermal stabilities, photoluminescence properties and electrochemical behavior in the solid state for CPs 1 and 2 have been investigated. The photophysical studies indicated that CPs 1 and 2 are potential semiconductive materials. Moreover, both CPs 1 and 2 show high photocatalytic efficiency for the degradation of methylene blue (MB) under UV light irradiation and exhibit good stability and recyclability. A possible photocatalytic mechanism is speculated by introducing t-butyl alcohol (TBA) as a widely used ˙OH scavenger.

19.
Dalton Trans ; 45(43): 17474-17484, 2016 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-27739548

RESUMEN

Two Cu(i) cyanide coordination polymers (CPs), namely, [Cu2(L1)(CN)2]n (1) and [Cu2(L2)(CN)2]n (2) (L1 = 4,4'-bis(2-methylbenzimidazol-1-ylmethyl)biphenyl, L2 = 4,4'-bis(5,6-dimethylbenzimidazol-1-ylmethyl)biphenyl) were synthesized and structurally characterized by single crystal X-ray diffraction, IR spectroscopy, X-ray powder diffraction and elemental analysis. The cyanide ligands in these CPs are generated in situ from the C-C bond cleavage of acetonitrile under solvothermal conditions, which is environmentally friendly and used conveniently. CP 1 features a three-fold interpenetration 3D framework consisting of Cu10(CN)6(L1)4 rings, which represents the first investigation on introducing bis(benzimidazole) ligands into copper(i) cyanide CPs with ThSi2 topology, while CP 2 exhibits a two-dimensional (6,3) layered structure containing Cu6(CN)4(L2)2 rings. The thermal stabilities, and photoluminescence and electrochemical behavior in the solid state of CPs 1 and 2 have been investigated in detail. Moreover, both CP 1 and CP 2 manifest promising photocatalytic activities (photodegradation efficiency using CP 1 is 90.8% and using CP 2 is 87.2%) for the degradation of methylene blue (MB) under UV light irradiation. A possible photocatalytic mechanism is suggested by introducing t-butyl alcohol (TBA) as a widely used ˙OH scavenger.

20.
Dalton Trans ; 45(6): 2426-9, 2016 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-26786714

RESUMEN

A 3D 4-coordinated self-catenated metal-organic framework {[Co(bibp)(1,4-chdc)]·2H2O}n (1) (bibp = 4,4'-bis(1-imidazolyl)biphenyl, 1,4-H2chdc = 1,4-cyclohexanedicarboxylic acid) has been synthesized by hydrothermal reaction and its structure has been determined. This framework buries an unprecedented 4-coordinated self-catenated net that can be represented as an array of honeycomb-like units catenated in an inclined mode, with the highest topological density among the 4-coordinated nets that occur in crystal structures. Additionally, the thermogravimetric, photo-catalytic and electrochemical behaviors have been investigated.

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