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1.
Environ Res ; 241: 117619, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-37952855

RESUMO

Multi-walled carbon nanotube (MWCNT) exposure was observed to cause damages on the viability of ocular cells, however, the underlying mechanisms remain not well understood. Epigenetic alterations that regulate gene expression have been identified as a major responsiveness to environmental challenge. Thus, the aim of this study was to screen methylation-regulated genes involved in MWCNT exposure. The Illumina Human Methylation 850 K array was employed to determine the genome-wide DNA methylation profile of human retinal pigment epithelial cell line (ARPE-19) exposed to 50% inhibition concentration of MWCNTs (100 µg/ml) for 24 h or without (n = 3 for each group). Then, the transcriptome data obtained by high-throughput RNA sequencing previously were integrated with DNA methylome to identify the overlapped genes. As a result, the integrative bioinformatics analysis identified that compared with controls, FA complementation group C (FANCC) was hypermethylated and downregulated in MWCNT-exposed ARPE-19 cells. Quantitative real-time polymerase chain reaction analysis confirmed the mRNA expression level of FANCC was significantly decreased following MWCNT treatment and the addition of DNA methylation inhibitor 5-Aza-deoxycytidine (10 µM) reversed this decrease. Pyrosequencing analysis further validated the hypermethylation status at the 5'-untranslated promoter region of FANCC (cg14583550) in MWCNT-exposed ARPE-19 cells. Protein-protein interaction network and function analyses predicted that FANCC may contribute to MWCNT-induced cytotoxicity by interacting with heat shock protein 90 beta family member 1 and then upregulating cytokine interleukin-6 and apoptosis biomarker caspase 3. In conclusion, the present study links the epigenetic modification of FANCC with the pathogenesis of MWCNT-induced retinal toxicity.


Assuntos
Metilação de DNA , Nanotubos de Carbono , Humanos , Nanotubos de Carbono/toxicidade , Células Epiteliais , Epigênese Genética , Linhagem Celular , Proteína do Grupo de Complementação C da Anemia de Fanconi/metabolismo
2.
Environ Res ; 247: 118106, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38224941

RESUMO

Exposure to large-size particulate air pollution (PM2.5 or PM10) has been reported to increase risks of aging-related diseases and human death, indicating the potential pro-aging effects of airborne nanomaterials with ultra-fine particle size (which have been widely applied in various fields). However, this hypothesis remains inconclusive. Here, a meta-analysis of 99 published literatures collected from electronic databases (PubMed, EMBASE and Cochrane Library; from inception to June 2023) was performed to confirm the effects of nanomaterial exposure on aging-related indicators and molecular mechanisms in model animal C. elegans. The pooled analysis by Stata software showed that compared with the control, nanomaterial exposure significantly shortened the mean lifespan [standardized mean difference (SMD) = -2.30], reduced the survival rate (SMD = -4.57) and increased the death risk (hazard ratio = 1.36) accompanied by upregulation of ced-3, ced-4 and cep-1, while downregulation of ctl-2, ape-1, aak-2 and pmk-1. Furthermore, multi-transcriptome data associated with nanomaterial exposure were retrieved from Gene Expression Omnibus (GSE32521, GSE41486, GSE24847, GSE59470, GSE70509, GSE14932, GSE93187, GSE114881, and GSE122728) and bioinformatics analyses showed that pseudogene prg-2, mRNAs of abu, car-1, gipc-1, gsp-3, kat-1, pod-2, acdh-8, hsp-60 and egrh-2 were downregulated, while R04A9.7 was upregulated after exposure to at least two types of nanomaterials. Resveratrol (abu, hsp-60, pod-2, egrh-2, acdh-8, gsp-3, car-1, kat-1, gipc-1), naringenin (kat-1, egrh-2), coumestrol (egrh-2) or swainsonine/niacin/ferulic acid (R04A9.7) exerted therapeutic effects by reversing the expression levels of target genes. In conclusion, our study demonstrates the necessity to use phytomedicines that target hub genes to delay aging for populations with nanomaterial exposure.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Animais , Poluentes Atmosféricos/toxicidade , Poluição do Ar/análise , Caenorhabditis elegans/genética , Exposição Ambiental/análise , Longevidade/genética , Material Particulado/análise , Transcriptoma
3.
Artigo em Inglês | MEDLINE | ID: mdl-38843411

RESUMO

Purpose: This research was conducted to construct an ankle pump motion counter and system with orthopedic characteristics and analyze the impacts of fast-track surgery on postoperative deep venous thrombosis (DVT) among patients with lower limb fractures. Methods: First, an ankle pump motion counter system was set up to detect postoperative rehabilitation training (Hardware design: This involves components such as an accelerometer sensor, microcontroller, circuit design, power supply, and wireless module. The accelerometer sensor is used to monitor key points and capture motion signals, while the microcontroller handles frequency calculations and generates alerts for abnormal ankle pump motion parameters. Circuit design ensures the proper functioning of the device, and the power supply meets the requirements of the ankle pump motion counter. The wireless module is used for data transmission and communication with other devices. Software design: This includes software design for both the patient and doctor sides. The software design involves defining software requirements and module divisions, designing data acquisition and filtering programs, developing programs for data parameter reading and writing, implementing communication protocols, designing data communication programs, and creating rehabilitation training plans and training record programs). Then, a retrospective analysis was carried out for the subjects (100 patients with lower limb fractures treated in Zhejiang Hospital between June 2021 and June 2022. They were randomly enrolled into control and experimental groups (50 cases each). The ankle pump motion counter was utilized for the patients in the experimental group. Before surgery, gender, age, the incidence of venous thromboembolism (VTE), and the muscle strength of both lower limbs of the two groups were recorded. After surgery, numerical rating scale (NRS) pain scores, D-dimer (D-D), and average length of hospitalization 3 d after surgery and venous thrombosis of both lower limbs 5 d after surgery of two groups were compared. Results: D-D of the control group was significantly higher than that of the experimental group 3 days after surgery (P < .05), while the NRS pain score was relatively lower (P < .05). The average hospitalization length for the experimental group was 10.2 days versus 16.2 days for the control group. The incidence of VTE 5 days after the surgery was 2% for the experimental group compared to 6% for the control group (P < .05). Conclusion: The ankle pump motion counter system has the potential to improve VTE prevention, enhance patient compliance, streamline healthcare delivery, standardize care, and enable data-driven decision-making at a wider clinical level. By accurately monitoring ankle pump exercises and providing real-time feedback, this system can contribute to better patient outcomes, save time for healthcare providers, and facilitate evidence-based practices in the prevention of postoperative DVT among patients with lower limb fractures.

4.
World J Microbiol Biotechnol ; 40(8): 246, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38902402

RESUMO

Saccharomyces cerevisiae, the primary microorganism involved in ethanol production, is hindered by the accumulation of ethanol, leading to reduced ethanol production. In this study, we employed histidine-modified Fe3O4 nanoparticles (His-Fe3O4) for the first time, to the best of our knowledge, as a method to enhance ethanol yield during the S. cerevisiae fermentation process. The results demonstrated that exposing S. cerevisiae cells to Fe3O4 nanoparticles (Fe3O4 NPs) led to increased cell proliferation and glucose consumption. Moreover, the introduction of His-Fe3O4 significantly boosted ethanol content by 17.3% (p < 0.05) during fermentation. Subsequent findings indicated that the increase in ethanol content was associated with enhanced ethanol tolerance and improved electron transport efficiency. This study provided evidence for the positive effects of His-Fe3O4 on S. cerevisiae cells and proposed a straightforward approach to enhance ethanol production in S. cerevisiae fermentation. The mediation of improved ethanol tolerance offers significant potential in the fermentation and bioenergy sectors.


Assuntos
Etanol , Fermentação , Glucose , Histidina , Saccharomyces cerevisiae , Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/crescimento & desenvolvimento , Etanol/metabolismo , Histidina/metabolismo , Glucose/metabolismo , Transporte de Elétrons/efeitos dos fármacos , Nanopartículas de Magnetita
5.
Mikrochim Acta ; 190(9): 344, 2023 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-37542665

RESUMO

A novel MIL-88-NH2@COF composite was produced by in situ growth of covalent organic framework (COF) on the metal-organic framework (MOF) surface. To obtain a coating fiber for solid-phase microextraction (SPME), the MIL-88-NH2@COF composite physically adhered to the stainless steel wire. Combined with gas chromatography-flame ionization detection (GC-FID), various analytes such as chlorophenols (CPs), phthalates (PAEs), and polycyclic aromatic hydrocarbons (PAHs) were extracted and determined to evaluate the extraction performance of MIL-88-NH2@COF coated fibers and explore their extraction mechanism. This composite exhibit excellent extraction performance and adsorption capacity for various analytes, especially for PAHs with enrichment factor up to 9858. The SPME-GC-FID method based on MIL-88-NH2@COF fiber was established for the determination of five PAHs after the main extraction conditions were optimized. Under optimal conditions, the proposed technique showed a wide linear range (1-150 ng mL-1) with a low limit of detection (0.019 ng mL-1) and a high coefficient of determination (R2 > 0.99). The developed SPME-GC-FID method was used to determine PAHs in green tea and black tea samples, with good recoveries of 51.70-103.64% and 68.56-103.64%, respectively. It is worth mentioning that this is the first time MIL-88-NH2@COF composites have been prepared and applied to SPME. The preparation method of the composite provides a new idea in adsorbent preparation, which will contribute to the field of SPME.

6.
Analyst ; 147(11): 2549-2557, 2022 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-35546319

RESUMO

The group specific assay of total aflatoxins (AFs) often requires specific antibodies. A controllable staining colorimetric method was proposed to determine AFs by exploiting controllable electrostatic-staining of carboxylated cellulose membranes (CCMs) with Hg2+-capped gold nanoparticles (AuNPs). Under electrostatic force, Hg2+ connects AuNPs and CCMs like a bridge, causing CCMs to be stained by AuNPs. The two adjacent carbonyl groups in the AF structure can chelate Hg2+. When AFs are present, Hg2+ and AFs will form complexes, which reduces the attachment of AuNPs on the CCMs. Therefore, the different degrees of electrostatic-staining of CCMs show different color changes. Based on this phenomenon, a naked-eye colorimetric detection assay of AFs was designed. The visual limit of detection (VLOD) reached 10 ppb, which makes it easily and effectively complete the early-warning and semi-quantitative detection of AFs. To our knowledge, this is the first method for colorimetric detection of AFs based on the controllable electrostatic-staining mechanism, which can be used for the determination of AFs in actual water samples such as beer and beverages. Besides, the colorimetric sensing method based on the controllable electrostatic-staining mechanism provides a novel methodology for early-warning and semi-quantitative detection of toxic and hazardous substances.


Assuntos
Aflatoxinas , Mercúrio , Nanopartículas Metálicas , Aflatoxinas/análise , Ácidos Carboxílicos , Celulose , Colorimetria/métodos , Ouro/química , Nanopartículas Metálicas/química , Coloração e Rotulagem , Água
7.
Mikrochim Acta ; 189(12): 449, 2022 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-36396739

RESUMO

A highly fluorinated porphyrin-based covalent organic frameworks magnetic adsorbent (FPy-COF@PDA@Fe3O4) was fabricated by using polydopamine (PDA) grafting Fe3O4 nanospheres as magnetic core and FPy-COF as shell for magnetic solid phase extraction (MSPE) of fluoroquinolones (FQs). FPy-COF was constructed by using 5,15-bis(4-aminophenyl)-10,20-bis(perfluorophenyl)porphyrin and 4,4'-biphenyldicarboxaldehyde as two building blocks. PDA as a bridge grafting on the surface of Fe3O4 nanospheres facilitated the growth of FPy-COF. The morphology and structure of FPy-COF@PDA@Fe3O4 adsorbent were characterized in detail. The prepared magnetic adsorbent exhibited good extraction capability to amphiphilic FQs due to their superior chemical affinities such as fluorophilic interaction and hydrogen-bond interaction from nitrogen-rich skeleton. Under the optimized conditions, the MSPE method combined with high performance liquid chromatography with ultraviolet detection (HPLC-UV) was developed to sensitively quantify trace level of six FQs in milk samples. The developed MSPE-HPLC method showed good linearity with wide concentration range, precision, and low limits of detection (S/N = 3) for six FQs as low as 2.3 ngꞏmL-1 in milk. The extraction recoveries of different spiked concentrations were in the range 77.8-110.4% for milk samples with RSD less than 9.7%.


Assuntos
Estruturas Metalorgânicas , Nanosferas , Porfirinas , Estruturas Metalorgânicas/química , Fluoroquinolonas/análise , Extração em Fase Sólida/métodos , Fenômenos Magnéticos
8.
Mikrochim Acta ; 189(10): 384, 2022 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-36125580

RESUMO

A new iron porphyrin-based organic polymer (Fe-POP) was synthesized through the William ether reaction. The as-prepared Fe-POP presented high chemical stability, wide pore distribution, high iron content, and strong affinity with 3,3',5,5'-tetramethylbenzidine (TMB) and hydrogen peroxide (H2O2), which contributed to its excellent peroxidase-mimicking performance. In the presence of H2O2, Fe-POP could catalyze the transparent TMB into blue ox-TMB, which could be easily distinguished by the naked eyes. Moreover, glutathione (GSH) and ascorbic acid (AA) could convert blue ox-TMB into colorless TMB due to the inhibitory effect of GSH/AA to the catalytic oxidation of TMB. Based on this phenomenon, a rapid and sensitive colorimetric method for the assay of H2O2, GSH, and AA was developed using Fe-POP as sensor. The detection limits of H2O2, GSH, and AA  were 1.37, 0.44, and 0.33 µM, respectively. Finally, the colorimetric method based on Fe-POP was used to evaluate the GSH and AA content in real samples, which provided the guidance for GSH and AA supplements in our daily diet, suggesting the significant potential of Fe-POP in practical applications.


Assuntos
Colorimetria , Porfirinas , Ácido Ascórbico/química , Benzidinas , Colorimetria/métodos , Corantes/química , Éteres , Glutationa/química , Peróxido de Hidrogênio/química , Ferro , Oxirredutases , Peroxidase , Peroxidases/química , Polímeros , Porosidade , Porfirinas/química
9.
Int J Mol Sci ; 23(22)2022 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-36430949

RESUMO

Organic nanomaterials have attracted considerable attention in the area of photodynamic and photothermal therapy, owing to their outstanding biocompatibility, potential biodegradability, well-defined chemical structure, and easy functionalization. However, it is still a challenge to develop a single organic molecule that obtains both photothermal and photodynamic effects. In this contribution, we synthesized a new boron-dipyrromethene (BODIPY)-based derivative (DPBDP) with an acceptor-donor-acceptor (A-D-A) structure by coupling 3,6-di(2-thienyl)-2,5-dihydropyrrolo [3,4-c] pyrrole-1,4-dione (DPP) and BODIPY. To enhance the hydrophilicity of the BODIPY derivative, the polyethylene glycol (PEG) chains were introduced to the meso- position of BODIPY core. The amphiphilic DPBDP was then self-assembled into related nanoparticles (DPBDP NPs) with improved hydrophilicity and enhanced absorbance in the NIR region. DPBDP NPs could simultaneously generate the singlet oxygen (1O2) and heat under the irradiation of a single laser (690 nm). The 1O2 quantum yield and photothermal conversion efficiency (PCE) of DPBDP NPs were calculated to be 14.2% and 26.1%, respectively. The biocompatibility and phototherapeutic effect of DPBDP NPs were evaluated through cell counting kit-8 (CCK-8) assay. Under irradiation of 690 nm laser (1.0 W/cm2), the half maximal inhibitory concentration (IC50) of DPBDP NPs was calculated to be 16.47 µg/mL. Thus, the as-prepared DPBDP NPs could be acted as excellent candidates for synergistic photodynamic/photothermal therapy.


Assuntos
Nanopartículas , Neoplasias , Humanos , Boro , Células HeLa , Nanopartículas/química , Neoplasias/tratamento farmacológico
10.
Int J Mol Sci ; 23(16)2022 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-36012486

RESUMO

Carbon dots (CDs) show great potential in bioimaging and biosensing because of their good biocompatibility and excellent optical properties. However, CDs with intense red emissions for sensitive and selective detection are rarely reported. Herein, we prepared the red-emissive carbon dots (RCDs) through a facile hydrothermal method using tetra (4-carboxyphenyl) porphyrin (TCPP) and thiourea as starting materials. The obtained RCDs were characterized by TEM, XRD, and XPS. RCDs exhibited high water solubility and strong red emission (λem = 650 nm), with the fluorescence quantum yield as high as 26.7%, which was greatly higher than that of TCPP. Moreover, the as-prepared RCDs could be acted as a highly selective and sensitive probe for the detection of Hg2+ and glutathione (GSH) through the fluorometric titration method. The detection limits of Hg2+ and GSH were calculated to be 1.73 and 1.6 nM, respectively. The cellular experiments demonstrated the good biocompatibility of RCDs and their feasibility in bioimaging. Thus, this work provided a simple strategy to design and synthesize the highly red-emissive carbon dots, which showed promising application in biological and environmental assays.


Assuntos
Mercúrio , Pontos Quânticos , Carbono , Corantes Fluorescentes , Glutationa , Nitrogênio , Espectrometria de Fluorescência/métodos , Enxofre
11.
Int J Mol Sci ; 23(18)2022 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-36142164

RESUMO

A series of N-arylsulfonyl-indole-2-carboxamide derivatives have been identified as potent fructose-1,6-bisphosphatase (FBPase) inhibitors (FBPIs) with excellent selectivity for the potential therapy of type II diabetes mellitus. To explore the structure-activity relationships (SARs) and the mechanisms of action of these FBPIs, a systematic computational study was performed in the present study, including three-dimensional quantitative structure-activity relationship (3D-QSAR) modeling, pharmacophore modeling, molecular dynamics (MD), and virtual screening. The constructed 3D-QSAR models exhibited good predictive ability with reasonable parameters using comparative molecular field analysis (q2 = 0.709, R2 = 0.979, rpre2 = 0.932) and comparative molecular similarity indices analysis (q2 = 0.716, R2 = 0.978, rpre2 = 0.890). Twelve hit compounds were obtained by virtual screening using the best pharmacophore model in combination with molecular dockings. Three compounds with relatively higher docking scores and better ADME properties were then selected for further studies by docking and MD analyses. The docking results revealed that the amino acid residues Met18, Gly21, Gly26, Leu30, and Thr31 at the binding site were of great importance for the effective bindings of these FBPIs. The MD results indicated that the screened compounds VS01 and VS02 could bind with FBPase stably as its cognate ligand in dynamic conditions. This work identified several potential FBPIs by modeling studies and might provide important insights into developing novel FBPIs.


Assuntos
Diabetes Mellitus Tipo 2 , Frutose-Bifosfatase , Aminoácidos , Frutose , Humanos , Indóis/farmacologia , Ligantes , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Relação Quantitativa Estrutura-Atividade
12.
Toxicol Appl Pharmacol ; 412: 115391, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33387576

RESUMO

Long-term exposure to carbon nanotubes (CNTs) has been reported to induce malignant transformation. This study aimed to screen candidate biomarkers for monitoring occupational workers to prevent the development of lung cancer. mRNA (GSE56104) and methylation (GSE153246) profiles of lung epithelial BEAS-2B cells exposed to malignant transformation dose of single-walled CNTs or control medium were downloaded from Gene Expression Omnibus database. A total of 1513 differentially expressed genes (DEGs) and 912 differentially methylated genes (DMGs) were identified using LIMMA method. The weighted correlation network analysis identified blue and turquoise modules were associated with malignant transformation of BEAS-2B cells, 124 DMGs of which were overlapped with DEGs. The mRNA and methylation levels of four methylation-driven DEGs were validated in both lung adenocarcinoma (LUAD) and squamous cell carcinomas (LUSC) of The Cancer Genome Atlas dataset and they were associated with overall survival of LUAD patients. Downregulation of PXMP4 and MCOLN2, while upregulation of MET was confirmed in both LUSC and LUAD via Human Protein Atlas analysis. PXMP4 and MET protein levels were also supported in the proteomic analysis of LUAD. Receiver operating characteristic (ROC) curve analysis showed the combination of four genes may be the optimal biomarker for predicting lung cancer, with the area under ROC curve >0.9. Function analysis revealed BARX2 may interact with CCND1 to regulate cell cycle; MET and PXMP4/MCOLN2 may positively correlate with CCR5/IL-6 or GATA3/HLA-DPB1/HLA-DPA1 to involve immune regulation. In conclusion, these four methylation-driven genes may be candidate prognostic and diagnostic biomarkers for single-walled CNT-related lung cancer.


Assuntos
Biomarcadores Tumorais/genética , Transformação Celular Neoplásica/induzido quimicamente , Metilação de DNA , Células Epiteliais/efeitos dos fármacos , Neoplasias Pulmonares/induzido quimicamente , Pulmão/efeitos dos fármacos , Nanotubos de Carbono/toxicidade , Biomarcadores Tumorais/metabolismo , Linhagem Celular , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Transformação Celular Neoplásica/patologia , Bases de Dados Genéticas , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , Humanos , Pulmão/metabolismo , Pulmão/patologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Exposição Ocupacional/efeitos adversos , Prognóstico , Mapas de Interação de Proteínas , Transcriptoma
13.
Anal Bioanal Chem ; 413(2): 613-624, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33159212

RESUMO

The development of metal nanoparticles (MNP) combined with a metal-organic framework (MOF) has received more and more attention due to its excellent synergistic catalytic ability, which can effectively broaden the scope of catalytic reactions and enhance the catalytic ability. In this work, we developed a novel ternary nanocomposite named Cu2O-mediated Au nanoparticle (Au NP) grown on MIL-53(Fe) for real-time monitoring of hydrogen peroxide (H2O2) released from living cells. First, Cu2O-MIL-53(Fe) was prepared by redox assembly technology, which provided the growth template, and active sites for AuCl4-. Au@Cu2O-MIL-53(Fe)/GCE biosensor was prepared by further loading nano-Au uniformly on the surface of Cu2O by electrochemical deposition. Compared to individual components, the hybrid nanocomposite showed superior electrochemical properties as electrode materials due to the synergistic effect between AuNPs, Cu2O, and MIL-53(Fe). Electrochemical measurement showed that the Au@Cu2O-MIL-53(Fe)/GCE biosensor presented a satisfactory catalytic activity towards H2O2 with a low detection limit of 1.01 µM and sensitivity of 351.57 µA mM-1 cm-2 in the linear range of 10-1520 µM. Furthermore, this biosensor was successfully used for the real-time monitoring of dynamic H2O2 activated by PMA released from living cells. And the great results of confocal fluorescence microscopy of the co-culture cells with PMA and Au@Cu2O-MIL-53(Fe) verified the reliability of the biosensor, suggesting its potential application to the monitoring of critical pathological processes at the cellular level.


Assuntos
Cobre/análise , Nanopartículas Metálicas/química , Estruturas Metalorgânicas/química , Células A549 , Técnicas Biossensoriais , Catálise , Técnicas de Cocultura , Técnicas Eletroquímicas/métodos , Eletroquímica/métodos , Eletrodos , Galvanoplastia , Ouro/química , Grafite/química , Humanos , Peróxido de Hidrogênio/química , Limite de Detecção , Microscopia Confocal , Microscopia de Fluorescência , Nanocompostos/química , Oxirredução , Reprodutibilidade dos Testes
14.
Mikrochim Acta ; 188(5): 160, 2021 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-33834299

RESUMO

A novel electrochemical sensor based on Cu-hemin metal-organic-frameworks nanoflower/three-dimensional reduced graphene oxide (Cu-hemin MOFs/3D-RGO) was constructed to detect H2O2 released from living cells. The nanocomposite was synthesized via a facile co-precipitation method using hemin as the ligand, then decorated with 3D-RGO. The prepared Cu-hemin MOFs showed a 3D hollow spherical flower-like structure with a large specific surface area and mesoporous properties, which could load more biomolecules and greatly enhance the stability by protecting the activity of hemin. In addition, the introduction of 3D-RGO effectively enhanced the conductivity of Cu-hemin MOFs. Thus, the proposed sensor (Cu-hemin MOFs/3D-RGO/GCE) showed excellent electrochemical performances towards H2O2 with a wide linear range (10-24,400 µM), high sensitivity (207.34 µA mM-1 cm-2), low LOD (0.14 µM), and rapid response time (less than 3 s). Most importantly, we prepared a Cu-hemin MOFs/3D-RGO/ITO electrode with cells growing on it. Compared with detecting H2O2 in cell suspension by GCE-based electrode, adhesion of cells on ITO could shorten the diffusion distance of H2O2 from solution to the surface of the electrode and achieve in situ and a real-time monitor of H2O2 released by living cells. This self-supported sensing electrode showed great potential applications in monitoring the pathological and physiological dynamics of cancer cells.


Assuntos
Grafite/química , Peróxido de Hidrogênio/sangue , Estruturas Metalorgânicas/química , Nanocompostos/química , Células A549 , Cobre/química , Técnicas Eletroquímicas/instrumentação , Técnicas Eletroquímicas/métodos , Eletrodos , Hemina/química , Humanos , Limite de Detecção , Reprodutibilidade dos Testes
15.
Int J Mol Sci ; 22(17)2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34502550

RESUMO

The ionotropic GABAA receptor (GABAAR) has been proven to be an important target of atypical antipsychotics. A novel series of imidazo [1,2-a]-pyridine derivatives, as selective positive allosteric modulators (PAMs) of α1-containing GABAARs with potent antipsychotic activities, have been reported recently. To better clarify the pharmacological essentiality of these PAMs and explore novel antipsychotics hits, three-dimensional quantitative structure-activity relationships (3D-QSAR), molecular docking, pharmacophore modeling, and molecular dynamics (MD) were performed on 33 imidazo [1,2-a]-pyridines. The constructed 3D-QSAR models exhibited good predictive abilities. The dockings results and MD simulations demonstrated that hydrogen bonds, π-π stackings, and hydrophobic interactions play essential roles in the binding of these novel PAMs in the GABAAR binding pocket. Four hit compounds (DS01-04) were then screened out by the combination of the constructed models and computations, including the pharmacophore model, Topomer Search, molecular dockings, ADME/T predictions, and MD simulations. The compounds DS03 and DS04, with higher docking scores and better predicted activities, were also found to be relatively stable in the binding pocket by MD simulations. These results might provide a significant theoretical direction or information for the rational design and development of novel α1-GABAAR PAMs with antipsychotic activities.


Assuntos
Regulação Alostérica , Simulação por Computador , Piridinas/metabolismo , Receptores de GABA-A/metabolismo , Esquizofrenia/metabolismo , Humanos , Ligação de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Ligantes , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Estrutura Molecular , Ligação Proteica , Conformação Proteica , Piridinas/química , Piridinas/farmacologia , Relação Quantitativa Estrutura-Atividade , Receptores de GABA-A/química , Esquizofrenia/tratamento farmacológico
16.
Int J Mol Sci ; 22(15)2021 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-34360886

RESUMO

Xanthine oxidase (XO) is an important target for the effective treatment of hyperuricemia-associated diseases. A series of novel 2-substituted 6-oxo-1,6-dihydropyrimidine-5-carboxylic acids (ODCs) as XO inhibitors (XOIs) with remarkable activities have been reported recently. To better understand the key pharmacological characteristics of these XOIs and explore more hit compounds, in the present study, the three-dimensional quantitative structure-activity relationship (3D-QSAR), molecular docking, pharmacophore modeling, and molecular dynamics (MD) studies were performed on 46 ODCs. The constructed 3D-QSAR models exhibited reliable predictability with satisfactory validation parameters, including q2 = 0.897, R2 = 0.983, rpred2 = 0.948 in a CoMFA model, and q2 = 0.922, R2 = 0.990, rpred2 = 0.840 in a CoMSIA model. Docking and MD simulations further gave insights into the binding modes of these ODCs with the XO protein. The results indicated that key residues Glu802, Arg880, Asn768, Thr1010, Phe914, and Phe1009 could interact with ODCs by hydrogen bonds, π-π stackings, or hydrophobic interactions, which might be significant for the activity of these XOIs. Four potential hits were virtually screened out using the constructed pharmacophore model in combination with molecular dockings and ADME predictions. The four hits were also found to be relatively stable in the binding pocket by MD simulations. The results in this study might provide effective information for the design and development of novel XOIs.


Assuntos
Ácidos Carboxílicos/química , Inibidores Enzimáticos/química , Simulação de Acoplamento Molecular/métodos , Simulação de Dinâmica Molecular , Xantina Oxidase/antagonistas & inibidores , Xantina Oxidase/química , Desenho de Fármacos , Inibidores Enzimáticos/uso terapêutico , Humanos , Ligação de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Hiperuricemia/tratamento farmacológico , Estrutura Molecular , Ligação Proteica , Relação Quantitativa Estrutura-Atividade
17.
Bioconjug Chem ; 31(3): 663-672, 2020 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-31884782

RESUMO

Light-activated phototherapy, including photothermal and photodynamic therapy, has become a new way for spatiotemporal control and noninvasive treatment of cancer. In this study, two new organic porphyrin molecules (NI-Por and NI-ZnPor) with donor (D)-acceptor (A) structure were designed and synthesized. The donor-acceptor pairs facilitated the intermolecular electron transfer, resulting in the enhancement of near-infrared (NIR) absorbance and nonradiative heat generation. After self-assembling, the nanoparticles were formed with the size around 60 nm. Relative to that of organic molecules, the absorption of NI-Por NPs and NI-ZnPor NPs broadened and red-shifted to the near-infrared region. Moreover, the porphyrin-containing nanoparticles can generate heat and reactive oxygen species (ROS) simultaneously induced by a single laser (635 nm). The intracellular reactive oxygen species production of NI-Por NPs and NI-ZnPor NPs was confirmed using DCFH-DA as an indicator. Furthermore, the localization of NI-Por NP and NI-ZnPor NP in HeLa cells was verified by fluorescence confocal laser microscopy. The photocytoxicity of two nanoparticles against HeLa cells was evaluated through the CCK-8 method. The IC50 of NI-Por NPs and NI-ZnPor NPs upon 635 nm laser irradiation was calculated to be 6.92 µg/mL and 5.86 µg/mL, respectively. Furthermore, the PDT/PTT synergistic effect of NPs under a 635 nm laser was verified through different treatment groups in vitro. All these results demonstrated that the as-prepared porphyrin-based nanoparticles are promising nanoagents for PDT/PTT in clinic.


Assuntos
Nanoestruturas/química , Naftalimidas/química , Fotoquimioterapia/métodos , Terapia Fototérmica/métodos , Porfirinas/química , Porfirinas/farmacologia , Células HeLa , Humanos , Espaço Intracelular/efeitos dos fármacos , Espaço Intracelular/metabolismo , Espaço Intracelular/efeitos da radiação , Porfirinas/uso terapêutico , Oxigênio Singlete/metabolismo
18.
Ophthalmic Res ; 63(6): 564-571, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32305986

RESUMO

PURPOSE: GATA4 has emerged as a novel regulator that plays a critical role in mediating senescence. However, the role of GATA4 in age-related cataract (ARC), the leading cause of visual impairment, requires further elucidation. METHODS: GATA4 expression was measured by quantitative RT-PCR and capillary Western immunoassay (WES). The MTT assay, EdU assay, and rhodamine-123/Hoechst and calcein-AM/propidium iodide double staining were used to investigate the role of GATA4 in the viability, proliferation, and apoptosis of cultured human lens epithelial cells (HLECs). RESULTS: HLECs were subjected to 3 different treatment models, including prolonged exposure to low-dose H2O2, UVB irradiation, and mild heating, to simulate senescence and apoptosis. GATA4 expression was significantly increased in these models in a time- and dose-dependent manner. Overexpression of GATA4 reduced cell viability, accelerated apoptosis development, and reduced the proliferation of HLECs. Furthermore, the expression of GATA4 from ARC was up-regulated at both mRNA and at protein level compared with clear lenses. CONCLUSION: GATA4 is up-regulated in all 3 models of HLECs in vitro and the cells from ARC lenses in vivo. Up-regulation of GATA4 mediates HLEC dysfunction. GATA4-mediated effects in HLECs would provide a novel insight into the pathogenesis of ARC.


Assuntos
Catarata/genética , Células Epiteliais/metabolismo , Fator de Transcrição GATA4/genética , Regulação da Expressão Gênica , Estresse Oxidativo , RNA/genética , Regulação para Cima , Idoso , Apoptose , Catarata/metabolismo , Catarata/patologia , Proliferação de Células , Sobrevivência Celular , Células Cultivadas , Células Epiteliais/patologia , Fator de Transcrição GATA4/biossíntese , Humanos , Pessoa de Meia-Idade , Transdução de Sinais , Dedos de Zinco
19.
Mikrochim Acta ; 187(6): 341, 2020 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-32444888

RESUMO

N-Doped silicon quantum dots (N-SiQD) were synthesized using N-[3-(trimethoxysily)propyl]-ethylenediamine and citric acid as silicon source and reduction agent, respectively. The N-SiQD shows a strong blue fluorescence with a high quantum yield of about 53%. It is found that a selective static quenching process occurs between N-SiQDs and Cu2+. Glyphosate can inhibit this phenomenon and trigger the rapid fluorescence enhancement of the quenched N-SiQDs/Cu2+ system due to the specific interaction between Cu2+ and glyphosate. With such a design, a turn-on fluorescent nanoprobe based on N-SiQD/Cu2+ system was established for rapid determination of glyphosate. The determination signal of N-SiQD/Cu2+ was measured at the optimum emission wavelength of 460 nm after excitation at 360 nm. Under optimal conditions, the turn-on nanoprobe showed a linear relationship between fluorescent response and glyphosate concentrations in the range 0.1 to 1 µg mL-1. The limit of determination was calculated to 7.8 ng mL-1 (3σ/S). Satisfactory recoveries were obtained in the determination of spiked water samples, indicating the potential use for environmental monitoring. Graphical abstract Schematic representation of N-SiQD/Cu2+ system for glyphosate determination. Fluorescence quenching of N-SiQDs induced by copper ions and the succedent fluorescent "turn on" triggered by glyphosate.


Assuntos
Corantes Fluorescentes/química , Glicina/análogos & derivados , Pontos Quânticos/química , Cobre/química , Fluorescência , Glicina/análise , Lagos/análise , Nitrogênio/química , Rios/química , Silício/química , Espectrometria de Fluorescência/métodos , Poluentes Químicos da Água/análise , Glifosato
20.
Anal Chem ; 91(24): 15461-15468, 2019 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-31710204

RESUMO

High-purity cellulose membranes prepared via a green pathway were used to attempt to enhance their performance of glucose detection compared with that of traditional filter paper. In this work, cellulose-based strips (CBS) for the low concentration of glucose detection have been designed based on a fast, sensitive, and easy enzyme colorimetric assay from porous and high-purity cellulose membranes (CM). Different from the traditional paper-based sensors that were made of commercially available filter paper, the cellulose-based membranes matrix was fabricated by a "green" route in that cellulose was dissolved in an aqueous NaOH/urea solution, and then modified by the sodium periodate oxidation method to immobilize the glucose oxidase (GOX) and horseradish peroxidase (HRP) with Schiff-base reaction. The structure and properties of CM and CBS were characterized by scanning electron microscopy (SEM), energy-dispersive X-ray mapping (EDS), Fourier-transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), etc. SEM images showed a porous, interpenetrating structure of CM, which benefited the enzyme immobilization and enzymatic reaction. When glucose solution was dropped onto the CBS, the color change from colorless to blue was only 5 min. The limit of detection (LOD) is 0.45 mM in the linear range of glucose from 1 to 11 mM. Moreover, the CBS had also been successfully used for glucose determination in real urine samples, and the color changes can be easily recorded by a simple camera to achieve the semiquantitative detection of glucose. This work provided a new design strategy for the cellulose-based functional materials which could be applied in biosensors, drug carriers, and biomedicine.


Assuntos
Celulose/química , Colorimetria/métodos , Glucose/química , Fitas Reagentes , Vasos Sanguíneos , Glicosúria , Humanos , Estrutura Molecular , Sensibilidade e Especificidade , Lágrimas/química
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