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1.
Inorg Chem ; 62(22): 8626-8634, 2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37219523

RESUMO

In situ fabrication of lead halide perovskite quantum dots (PQDs) is important for narrow-band emitters for LED displays due to the simple work procedure and convenient usability; however, the growth of PQDs is not readily controllable in the preparation, resulting in low quantum efficiency and environmental instability of PQDs. Here, we demonstrate an effective strategy to controllably prepare CsPbBr3 PQDs in polystyrene (PS) under the regulation of methylammonium bromide (MABr) via electrostatic spinning and thermal annealing techniques. MA+ slowed down the growth of CsPbBr3 PQDs and acted as a surface defect passivation reagent, which was proved by Gibbs free energy simulation, static fluorescence spectra, transmission electron microscopy, and time-resolved photoluminescence (PL) decay spectra. Among a series of prepared Cs1-xMAxPbBr3@PS (0 ≤ x ≤ 0.2) nanofibers, Cs0.88MA0.12PbBr3@PS shows the regular particle morphology of CsPbBr3 PQDs and the highest photoluminescence quantum yield of up to 39.54%. The PL intensity of Cs0.88MA0.12PbBr3@PS is 90% of the initial intensity after immersing in water for 45 days and 49% of the initial value after persistent ultraviolet (UV) irradiation for 27 days. A high color gamut containing 127% of the National Television Systems Committee standard with long-time working stability was also obtained on light-emitting diode package measurements. These results demonstrate that MA+ can effectively control the morphology, humidity, and optical stability of CsPbBr3 PQDs in the PS matrix.

2.
Gerontology ; 69(11): 1347-1357, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37725916

RESUMO

INTRODUCTION: Early-life factors were reported to exert influence on the health condition of individuals in the long-term. However, limited research explored the connection between early-life factors and multimorbidity in later years. METHODS: We utilized the data from the China Health and Retirement Longitudinal Study to assess this possible association in the present cross-sectional study. Multimorbidity was determined based on 14 common chronic diseases included in the study. Logistic regression was employed to examine the link between early-life factors and subsequent multimorbidity. RESULTS: Out of 7,578 participants who met the inclusion criteria for analysis, 3,765 (49.68%) were females. The mean age was 68.25 ± 6.70 years. Participants who rated their health during childhood as average (odds ratio [OR] 0.78, 95% confidence interval [CI] 0.63-0.96) or better [OR 0.72, 95% CI 0.57-0.91] were significantly less likely to experience multimorbidity in older life. By contrast, experiencing violence from two of the family members was significantly associated with future multimorbidity (OR [95% CI], 1.29 [1.04-1.60]). A superior family financial situation was also negatively associated with multimorbidity, with average (OR [95% CI], 0.72 [0.63-0.83]) and better off than average (OR [95% CI], 0.76 [0.62-0.93]). DISCUSSION: Individuals with poor health status, inferior family socioeconomic status, or experienced violence from family members in childhood were more likely to suffer from multimorbidity in later life. Enhanced social monitoring of potentially adverse conditions in youngsters and targeted interventions could help mitigate the progression of multimorbidity in later life.


Assuntos
Multimorbidade , Classe Social , Feminino , Humanos , Idoso , Masculino , Estudos Transversais , Estudos Longitudinais , Doença Crônica , China/epidemiologia
3.
Analyst ; 147(9): 1976-1985, 2022 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-35419580

RESUMO

Hypochlorous acid (HOCl) is widely used in daily production and life because of its green and strongly oxidizing properties. Additionally, as a vital reactive oxygen species (ROS), it is an innate immune system weapon and performs a critical function in many pathophysiology processes. In this paper, a novel water-soluble fluorescent probe, BMH, with excellent performance is designed and synthesized by simple condensation of benzocoumarin and 2-mercaptoethanol. BMH has specific selectivity, excellent sensitivity, ultra-fast response (<3 s), and a wide pH detection range. The fluorescence intensity of BMH has an excellent linear correlation with the concentration of HOCl in the scope of 0-10 µM, and the calculated detection limit (DL) is 2.45 nM. The intramolecular charge transfer (ICT) sensing mechanism of BL has been verified by fluorescence, UV, and MS studies as well as density functional theory (DFT) calculations. Furthermore, BMH can be incorporated into a solid-state visual sensor to detect HOCl conveniently. BMH was applied to detect HOCl-spiked actual water samples and achieved satisfying recovery rates. Also, the low-toxicity BMH can be successfully used to track changes in endogenous/exogenous HOCl in living cells. In short, BL provides a robust and reliable monitoring tool to reveal the biological functions of HOCl and ensure its safe use.


Assuntos
Corantes Fluorescentes , Ácido Hipocloroso , Fluorescência , Corantes Fluorescentes/química , Corantes Fluorescentes/toxicidade , Ácido Hipocloroso/química , Água/química
4.
Inorg Chem ; 61(17): 6493-6499, 2022 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-35436089

RESUMO

Introduction of chiral ligands has been regarded as an effective strategy to obtain nanoclusters with optical purity. However, how the chiral ligands work is still unclear due to the lack of structural comparison between racemic nanoclusters and the corresponding optically active ones. In this work, three structurally related Au24Cd2 nanoclusters, including one racemic and two homochiral nanoclusters, were synthesized, and their crystal structures were characterized using single-crystal X-ray crystallography (SC-XRD). Based on their crystal structures, the origin of the chirality in Au24Cd2 was found to be the twist of the kernel and the chiral arrangement of the metal-ligand surface. Au24Cd2 protected with chiral ligands exhibits a more twisted kernel than the racemic one. Therefore, the chirality of chiral diphosphine was found to transfer from the ligands to the metal-ligand interface and then to the metal core, inducing its distortion to produce enhanced chirality. In addition, the optical properties including optical absorption and circular dichroism of these structurally related Au24Cd2 nanoclusters were compared.

5.
Inorg Chem ; 61(46): 18450-18457, 2022 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-36351042

RESUMO

Structural transformation in nanoclusters is important not only in obtaining functional nanoclusters controllably but also in understanding their structural evolution. This study investigated the role of Cu2+ ions in structural transformation. It was revealed that Cu2+ exhibits two different functions, doping and oxidation, in determining the final products. Starting with a new silver nanocluster, [Ag25(2,5-DMBT)16(DPPF)3]+ (Ag25), a doping process would occur when no more than 0.5 equiv of Cu2+ was added, resulting in the formation of [Ag25-xCux(2,5-DMBT)16(DPPF)3]+ (Ag25-xCux). When 1 equiv of Cu2+ was introduced to Ag25, a structural transformation process would occur instead, forming [Ag22-xCux(2,5-DMBT)12(DPPF)4Cl4]2+ (Ag22-xCux). Considering the similar Cu doping amounts in Ag25-xCux and Ag22-xCux, an oxidation process induced by Cu2+ in the solution can account for this transformation process, which was further demonstrated by the addition of other oxidant substitutions. On the other hand, the role of other valence states of copper in the transformation of the Ag25 cluster was explored. It was found that copper powder can hardly change Ag25 and Cu+ can only proceed the doping process, both of which are different from the role of Cu2+. Overall, this work explores the role of copper in the transformation of the Ag25 cluster in detail, including its concentrations and valence states.

6.
Exp Eye Res ; 207: 108585, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33887222

RESUMO

Diabetic retinopathy (DR), characterized by intraretinal vessel formation, is a major complication in diabetes. Neovascularization is an important characteristic of DR, but its formation mechanism remains unclear. In this research, Malat1, miR-205-5p, and VEGF-A levels in high glucose (HG) treat-human retinal microvascular endothelial cells (hRMECs) was detected with qRT-PCR. CCK-8 assay, transwell assay, and tube formation assay was applied to access hRMEC viability, migration, and angiogenesis. Expression level of endothelial-mesenchymal transition (EndMT) markers (VE-cadherin, FSP1, and α-SMA) was detected by western blotting assay. Interaction among Malat1, miR-205-5p, and VEGF-A was confirmed by dual-luciferase reporter assay. Furthermore, in vivo DR mouse model was induced, and the effect of Malat1 on DR and EndMT markers was confirmed through hematoxylin-eosin (HE) staining and western blotting. As a result, Malat1 and VEGF-A was upregulated while miR-205-5p was suppressed under HG conditions. Malat1 could sponge miR-205-5p to regulate VEGF-A expression. Malat1 knockdown inhibited hRMEC proliferation, migration, and tube formation by targeting miR-205-5p under HG conditions. Furthermore, inhibition of Malat1 prevented the HG-induced EndMT process. In summary, Malat1 knockdown diminished hRMEC dysfunctions by regulating miR-205-5p/VEGF-A, providing a useful insight for exploring new therapeutic target for DR.


Assuntos
Retinopatia Diabética/prevenção & controle , Regulação da Expressão Gênica/fisiologia , Técnicas de Silenciamento de Genes , Glucose/farmacologia , MicroRNAs/genética , RNA Longo não Codificante/genética , Neovascularização Retiniana/prevenção & controle , Fator A de Crescimento do Endotélio Vascular/genética , Actinas/metabolismo , Animais , Antígenos CD/metabolismo , Western Blotting , Caderinas/metabolismo , Células Cultivadas , Retinopatia Diabética/genética , Retinopatia Diabética/metabolismo , Modelos Animais de Doenças , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Humanos , Camundongos Endogâmicos C57BL , MicroRNAs/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Neovascularização Retiniana/genética , Neovascularização Retiniana/metabolismo , Vasos Retinianos/citologia , Proteína A4 de Ligação a Cálcio da Família S100/metabolismo , Transfecção , Fator A de Crescimento do Endotélio Vascular/metabolismo
7.
Angew Chem Int Ed Engl ; 57(23): 6786-6790, 2018 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-29660210

RESUMO

Fingerprint fluorescence imaging has become one of the most prominent technologies in the field of forensic medicine, but it seldom considers the security protection of detection information, which is of great importance in modern society. Herein we demonstrate that luminescent TbIII -carboxymethyl cellulose (CMC) complex binding aptamer hydrogels that are reversibly responsive to ClO- /SCN- can be used for the selective detection, protection, and storage of fingerprint information. The imaging information of the fingerprint can be quenched and recovered by ClO- /SCN- regulation, respectively, resulting in reversible on/off conversion of the luminescence signals for the encryption and decryption of multiple levels of information. The present study opens new avenues for multilevel imaging, data recording, and security protection of fingerprint information with tunable fluorescent hydrogels.


Assuntos
Carboximetilcelulose Sódica/química , Dermatoglifia , Hidrogéis/química , Substâncias Luminescentes/química , Térbio/química , Ânions/química , Aptâmeros de Nucleotídeos/química , Humanos , Luminescência , Medições Luminescentes/métodos , Imagem Óptica/métodos
8.
Anal Chem ; 89(15): 8140-8147, 2017 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-28682588

RESUMO

Portable, low-cost, and quantitative detection of cancer cells at home and in the field has the potential to revolutionize medical diagnostics. We first report the design and synthesis of highly efficient folic-acid-conjugated hydrogen-generation tube-in-tube CuO/Co3O4 heterojunction nanofibers for highly sensitive and rapid recognition of cancer cells through a pressure signal under visible-light irradiation. The resultant nanofibers can dramatically enhance the hydrogen-generation activity of ammonia borane under visible-light irradiation. Such hydrogen-generation reaction can translate a molecular recognition event between folic acid and folate receptor to measurable pressure signal readout through a low-cost and portable pressure meter for target cancer cell detection. Limits of detection (LODs) down to 50 cells mL-1 in only 15 min can be achieved. This result is superior to those of the other reported methods, indicating the superiority of the new pressure-based sensor in terms of sensitivity. The present study establishes the pressure meter as a useful tool for early clinical point-of-care cancer diagnosis.


Assuntos
Cobalto/química , Cobre/química , Técnicas Eletroquímicas , Hidrogênio/análise , Nanofibras/química , Óxidos/química , Animais , Catálise , Ácido Fólico/química , Células HeLa , Humanos , Hidrogênio/metabolismo , Limite de Detecção , Camundongos , Microscopia Confocal , Células NIH 3T3 , Pressão , Teoria Quântica
9.
Neurol Sci ; 37(8): 1327-33, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27146810

RESUMO

We purposed to identify underlying functional pathway cross-talk in Parkinson's disease (PD) through Monte Carlo cross-validation analysis. Microarray data set of E-GEOD-6613 was downloaded from ArrayExpress database. First, the identification of differentially expressed genes (DEGs) was implemented, following by extracting the potential disrupted pathway enriched by DEGs. In addition, a discriminating score (DS) was computed based on the distribution of gene expression levels by quantifying their pathway cross-talk for each pair of pathways. Furthermore, random forest (RF) classification model was utilized to identify the top ten paired pathways with high AUC between PD and healthy control samples using the tenfold cross-validation method. Finally, Monte Carlo cross-validation was repeated 50 times to explore the best pairs of pathways. After quantile normalization, a total of 9331 genes with higher than 0.25-fold quantile average across all samples were obtained. Totally, 42 DEGs and 19 differential pathways enriched from DEGs were identified. We then ranked each pathway according to their AUC values, the pair of pathways, phosphatidylcholine biosynthesis I, and PPAR signaling obtained the best AUC value of 0.942. Moreover, the paired pathways of mTOR signaling and CD28 signaling in T helper cells had higher AUC value of 0.837 in five bootstraps. Two paired pathways, including phosphatidylcholine biosynthesis I and PPAR signaling, as well as mTOR signaling and CD28 signaling in T helper cells were able to accurately classify PD and healthy control samples. Significantly, these paired pathways might be underlying biomarkers for early diagnosis and therapy of PD.


Assuntos
Método de Monte Carlo , Doença de Parkinson/genética , Transdução de Sinais/fisiologia , Área Sob a Curva , Antígenos CD28/genética , Bases de Dados Genéticas , Feminino , Perfilação da Expressão Gênica , Humanos , Masculino , Análise de Sequência com Séries de Oligonucleotídeos , Receptores Ativados por Proliferador de Peroxissomo/genética , Reprodutibilidade dos Testes , Serina-Treonina Quinases TOR/genética , Transferases (Outros Grupos de Fosfato Substituídos)
10.
Chemistry ; 20(36): 11549-55, 2014 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-25048270

RESUMO

Low cost, high activity and selectivity, convenient separation, and increased reusability are the main requirements for noble-metal-nanocatalyst-catalyzed reactions. Despite tremendous efforts, developing noble-metal nanocatalysts to meet the above requirements remains a significant challenge. Here we present a general strategy for the preparation of strongly coupled Fe(3)O(4) and palladium nanoparticles (PdNPs) to graphene sheets by employing polyethyleneimine as the coupling linker. Transmission electron microscopic images show that Pd and Fe(3)O(4) nanoparticles are highly dispersed on the graphene surface, and the mean particle size of Pd is around 3 nm. This nanocatalyst exhibits synergistic catalysis by Pd nanoparticles supported on reduced graphene oxide (rGO) and a tertiary amine of polyethyleneimine (Pd/Fe(3)O(4)/PEI/rGO) for the Tsuji-Trost reaction in water and air. For example, the reaction of ethyl acetoacetate with allyl ethyl carbonate afforded the allylated product in more than 99 % isolated yield, and the turnover frequency reached 2200 h(-1). The yield of allylated products was 66 % for Pd/rGO without polyethyleneimine. The catalyst could be readily recycled by a magnet and reused more than 30 times without appreciable loss of activity. In addition, only about 7.5 % of Pd species leached off after 20 cycles, thus rendering this catalyst safer for the environment.

11.
J Fluoresc ; 23(6): 1239-45, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23828513

RESUMO

In the paper, a novel rhodamine6G based fluorescent chemosensor bearing 3-carbaldehyde chromone was designed and synthesized. According to the fluorescence behavior toward several metal ions, it showed highly selectivity and sensitivity to Zn(II) over other commonly coexistent metal ions (Cu(II), Cd(II), Hg(II), Mg(II), K(I), Pb(II), Fe(III) and Cr(III)) in aqueous environment (pH = 7.4). Meanwhile the binding constant between Zn(II) and chemosensor achieved 6.21 × 10(11) M(-1) in aqueous media. Moreover, according to the Job plot, 1:1 stoichiometry between Zn(II) and sensor was deduced in aqueous media (pH = 7.4). The good selectivity and sensitivity in aqueous media effectively enhanced the application value of the fluorescent chemosensor for Zn(II).


Assuntos
Corantes Fluorescentes/química , Rodaminas/química , Zinco/análise , Corantes Fluorescentes/síntese química , Íons/análise , Modelos Moleculares , Estrutura Molecular , Rodaminas/síntese química , Espectrometria de Fluorescência , Água/química
12.
J BUON ; 18(4): 908-14, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24344016

RESUMO

PURPOSE: Cyclooxygenase-2 (COX-2), one isoform of cyclooxygenase proinflammatory enzymes, plays an important role in tumor development and progression. Researches of human cancers have revealed high expression levels of COX-2 in a variety of cancers including lung cancer. The mechanism of COX-2 in the pathogenesis of non-small cell lung cancer (NSCLC) cells is not well understood. METHODS: We constructed a lentivirus vector mediated RNA interference (RNAi) targeting COX-2 for the treatment of human NSCLC cells. RNAi technology was used to knockdown the expression of COX-2 in NSCLC cell lines. The efficiency and specificity was validated by quantitative real-time PCR and western blotting. The cell growth and cell cycle were determined by MTT and flow cytometry assay, respectively. Cell cycle-regulated gene expression, including cyclin D1, p21 and survivin, whose expression was modulated by COX-2, was also examined. RESULTS: LV-COX-2-silencing (si)RNA lentivirus vector was effective and its inhibitory effects on COX-2 mRNA and protein expression was efficient and specific. Gene knockdown of COX-2 by LV-COX-2-siRNA significantly inhibited the growth and induced cell cycle arrest of NSCLC cell lines. In addition, silence of COX-2 mediated by LV-COX-2-siRNA modulated the expression of cell cycle-regulated gene, upregulating p21 and downregulating cyclin D1 and survivin. CONCLUSIONS: Our findings imply that COX-2 and its signaling pathway may provide a novel therapeutic target for the treatment of NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/enzimologia , Proliferação de Células , Ciclo-Oxigenase 2/metabolismo , Vetores Genéticos , Lentivirus/genética , Neoplasias Pulmonares/enzimologia , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Ciclo Celular , Linhagem Celular Tumoral , Ciclina D1/genética , Ciclina D1/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Ciclo-Oxigenase 2/genética , Técnicas de Silenciamento de Genes , Humanos , Proteínas Inibidoras de Apoptose/genética , Proteínas Inibidoras de Apoptose/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Transdução de Sinais , Survivina , Transfecção
13.
Diabetol Metab Syndr ; 15(1): 239, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37993958

RESUMO

BACKGROUND: Irisin plays a key role in metabolic diseases, including type 2 diabetes mellitus (T2DM). However, the mechanism underlying the link between irisin and the development of T2DM, particularly in pancreatic islet ß-cells, remains unknown. METHODS: In vitro, Min6 cells were treated with high glucose (HG) to generate T2DM cell models. GSDMD-N staining, Western blotting assays, and ELISA were performed to measure the expression levels of GSDMD, caspase 1, IL-1ß, and IL-18. Next, the NLRP3 stimulator, ATP, was used to assess the effect of irisin on NLRP3 inflammasome. To evaluate the function of the Nrf2-TrX/TXNIP signaling axis, the Nrf2 inhibitor ML385 was used. For in vivo assessment, we first established T2DM model mice. Then, hematoxylin and eosin (H&E) staining was performed to observe the islet morphology, and the immunofluorescence technique was used to examine the mass of α and ß cells. To confirm the role of the Nrf2-TrX/TXNIP signaling axis, ML385 was injected into the mice. Immunofluorescence of Nrf2, caspase 1, and GSDMD was detected in the islet cells of the model mice to verify the results. RESULTS: We found that irisin treatment significantly decreased the expression of GSDMD-N (P31) and cleaved caspase-1 (p20), decreased caspase1 activity, and inhibited the secretion of IL-1ß and IL-18 in HG-treated Min6 cells. We also found that irisin inhibited oxidative stress and NLRP3 expression by activating the Nrf2-TrX/TXNIP signaling axis. Additionally, in the T2DM model mice, irisin enhanced the function of islet cells, decreased insulin resistance, and preserved the morphology of pancreatic islets. CONCLUSION: We showed in this study that irisin can be used for treating pyroptosis in HG-induced islet ß-cells and T2DM model mice. We also found that irisin inhibits pyroptosis and oxidative stress by inhibiting the NLRP3-GSDMD pathway and activating the Nrf2-TrX/TXNIP signaling axis.

14.
Endokrynol Pol ; 74(3): 277-284, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37335063

RESUMO

INTRODUCTION: Irisin is closely related to type 2 diabetes mellitus (T2DM) and other metabolic diseases. It can improve the homeostasis of T2DM. MiR-133a-3p is decreased in the peripheral blood of patients with T2DM. Forkhead box protein O1 (FOXO1) is widely expressed in beta-cells and affects the occurrence of diabetes through transcriptional regulation and signalling pathway regulation. MATERIAL AND METHODS: The miR-133a-3p inhibitor was constructed to verify the effect of irisin on pyroptosis through miR-133a-3p. Next, we predicted the presence of targeted binding sequences between FOXO1 and miR-133a-3p by bioinformatics software, which was then confirmed with a double fluorescence assay. Finally, the FOXO1 overexpression vector was used to further verify the effect of irisin through the miR-133a-3p/FOXO1 axis. RESULTS: We first observed that irisin inhibited the protein levels of N-terminal gasdermin D (GSDMD-N) and cleaved caspase-1 and the secretion of interleukins (IL): IL-1beta and IL-18 in Min6 cells treated with high glucoes (HG). Irisin inhibited pyroptosis of Min6 cells treated with HG by reinforcing miR-133a-3p. Then, FOXO1 was validated to be the target gene of miR-133a. Both miR-133a-3p inhibitor and overexpression of FOXO1 restrained the force of irisin on pyroptosis in HG-induced Min6 cells. CONCLUSION: We explored the protective effect of irisin on HG-induced pyroptosis of islet b-cells in vitro and explained its mechanism of inhibiting pyroptosis through the miR-133a-3p/FOXO1 axis, to provide a theoretical basis for finding new molecular targets to delay beta-cell failure and the treatment of T2DM.


Assuntos
Diabetes Mellitus Tipo 2 , Células Secretoras de Insulina , MicroRNAs , Humanos , Piroptose , MicroRNAs/metabolismo , Fibronectinas , Células Secretoras de Insulina/metabolismo , Glucose , Proteína Forkhead Box O1/genética , Proteína Forkhead Box O1/metabolismo
15.
J Fluoresc ; 21(3): 1091-102, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21161345

RESUMO

A novel Schiff base ligand, chromone-3-carbaldehyde-aminophenazone (L) and its Ln(III) (Ln = La, Yb) complexes were synthesized and characterized by physicochemical methods. The interaction between the ligand, Ln(III) complexes and calf thymus DNA in physiological buffer (pH=7.10) was investigated by using UV-vis spectroscopy, fluorescence spectra, ethidium bromide experiments and viscosity measurements, indicating that the studied compounds can all bind to DNA via an intercalation binding mode and the complexes have stronger binding affinity than the free ligand alone. Furthermore, antioxidant activity of the ligand and its complexes was determined by superoxide and hydroxyl radical scavenging methods in vitro, suggesting that Ln(III) complexes inhibit stronger antioxidant activity than the ligand alone and some standard antioxidants, such as mannitol and vitamin C.


Assuntos
Antioxidantes/química , DNA/química , Elementos da Série dos Lantanídeos/química , Bases de Schiff/química , Aminopirina , Cromonas/química , DNA/metabolismo , Ligantes
16.
Chem Commun (Camb) ; 57(38): 4682-4685, 2021 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-33977990

RESUMO

Herein, surface engineering was delicately performed to assemble two new Au-Cd alloy nanoclusters, including [Cd2Au17(S-c-C6H11)12(DPPP)2](BPh4) and Cd2Au29(TBBT)17(DPPF)2. Both the Au13 (in Cd2Au17) and Au25 (in Cd2Au29) cores were covered by two identical Au2Cd(SR)6 motifs and two diphosphine ligands. In addition, their optical properties were explored to give clues on the kernel- and surface-dependent electronic structures.

17.
Biosens Bioelectron ; 190: 113417, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34134071

RESUMO

The development of highly sensitive and simple detection methods for cancer cells is an important challenge to achieve early cancer diagnosis and effective treatment. In this paper, folic acid (FA)-conjugated platinum (IV) methylene blue (MB) coordination polymers nanorods (denoted as FA-PtCPs NRs) were developed by the photochemical method. The structure of the PtCPs NRs was investigated using the meta-dynamics and genetic algorithms (MTD-GC) method, and it was found that the coordination bond was formed between platinum (IV) and N atoms of MB. The field emission scanning electron microscope (FE-SEM) and transmission electron microscope (TEM) indicated that the morphology of PtCPs NRs was rod-like. The resulting FA-PtCPs NRs was used for the specific and ultra-sensitive temperature detection of cancer cells based on PtCPs NRs as a signal trigger unit and FA as a target recognition tool. After three-step reaction, oxidized 3,3',5,5'-tetramethylbenzidine (ox-TMB) with photothermal effect was obtained. Under 660 nm laser irradiation, such detection platform can convert the molecular recognition signal between FA and folate receptor (FR) of cancer cells into readable temperature value, which can be directly read by an ordinary thermometer, with a detection limit as low as 2 cells/mL. In addition, FA-PtCPs NRs could be used as fluorescent probes for in-situ bioimaging. Therefore, this photothermal sensing platform has a broad prospect in the field of point-of-care detection of cancer cells.


Assuntos
Técnicas Biossensoriais , Nanotubos , Neoplasias , Ácido Fólico , Neoplasias/diagnóstico , Platina , Polímeros
18.
Chem Sci ; 11(33): 8817-8827, 2020 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-34123135

RESUMO

Carrying out the in vivo syntheses of drugs toxic to tumors based on the specific features of the tumor microenvironment is critical for ensuring specific antitumor efficacy. However, achieving in situ high-yield synthetic toxic drugs from non-toxic agents and reducing their drug resistance in hypoxic tumors remain challenges. Herein we created a tumor-microenvironment-responsive porous Pt/Pt(iv) methylene blue coordination polymer nanoshuttle (Pt/PtMBCPNS) photosensitizer with spatiotemporally controlled O2 and singlet oxygen (1O2) self-sufficient for the in vivo high-yield synthesis of drugs and efficient hypoxic tumor therapy. After being endocytosed, the nanophotosensitizer as a cascade catalyst was observed to effectively catalyze the conversion of endogenous H2O2 to O2, and was hence found to play a dual role in the enhanced tumor therapy. PtMBCPNSs, upon being irradiated with red light, efficiently converted O2 into 1O2. Subsequently, 1O2 oxidized non-toxic 1,5-dihydroxynaphthalene to form the anticancer agent juglone with a high yield. In addition, O2 was found to be able to improve the hypoxic microenvironment without light irradiation, thus enhancing the antitumor efficacy of the produced drugs and reducing drug resistance. As a result, by enhancing the synergistic effect of the treatment, this nanophotosensitizer significantly inhibited the growth of tumors and avoided damage to normal tissues/organs. Collectively, this work highlights a robust nanoplatform with the spatiotemporally controlled in vivo high-yield synthesis of drugs and generation of O2 to help overcome the current limitations of chemical-based therapies against hypoxic tumors.

19.
ACS Appl Mater Interfaces ; 11(47): 44664-44672, 2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31692318

RESUMO

Covalent organic frameworks (COFs) have been proposed as alternative candidates for "smart" materials due to their ordered π-columnar structures. However, it remains a challenge to develop external-stimuli-responsive luminescent COFs for confidential information protection. Here, we have designed and synthesized a water-dispersible and smart responsive luminescent carboxymethyl cellulose-COF hydrogel encapsulated 5-(dimethylamino)-N,N-bis (pyridin-2-ylmethyl) napthalene-1-sulfonamide, named CMC-COF-LZU1⊃DPYNS, for latent fingerprint imaging and encryption. We show that the fluorescence of CMC-COF-LZU1⊃DPYNS is reversibly switchable upon addition of Cu2+/H2O. This effect endows potential applications of tunable luminescent COFs based hydrogel as an invisible security probe for imaging, recording, storage, and security of latent fingerprint information. It is shown that the latent fingerprint information incubated by the aptamer-functionalized CMC-COF-LZU1⊃DPYNS hydrogel is invisible in the presence of Cu2+, but three levels of fingerprint features with high-resolution patterns could be readable upon addition of H2O under UV light. The design strategy provides a promising platform for the development of smart responsive luminescent COFs and their detection and protection of valuable latent fingerprint information.

20.
Dalton Trans ; 48(17): 5735-5740, 2019 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-30972392

RESUMO

At present, though calcium (Ca) reagents with high calcium contents are widely synthesized, their wide application is limited due to their low absorption rates and poor bioavailability. Here we use a carboxymethyl cellulose (CMC) derivative with high water solubility and biocompatibility as a ligand to bind Ca2+. The resulting CaCMC complex exhibits remarkable solubility and absorbability under both basic and acidic conditions as well as in stomach mimicking and the gastrointestinal tract. Importantly, this Ca reagent shows high in vivo calcium bioavailability. Data from osteoporosis mouse models show that the CaCMC complex is superior to calcium carbonate in the treatment of osteoporosis. Therefore, the resulting CaCMC complex is used as a new, highly effective and desirable Ca supplement for daily life and clinical applications.


Assuntos
Materiais Biocompatíveis/farmacocinética , Cálcio/metabolismo , Cálcio/uso terapêutico , Carboximetilcelulose Sódica/química , Carboximetilcelulose Sódica/farmacocinética , Osteoporose/tratamento farmacológico , Osteoporose/metabolismo , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/metabolismo , Disponibilidade Biológica , Cálcio/administração & dosagem , Cálcio/farmacocinética , Carboximetilcelulose Sódica/metabolismo , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Tamanho da Partícula , Solubilidade , Propriedades de Superfície
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