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1.
Sci Rep ; 14(1): 16331, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39009689

RESUMEN

To determine the independent risk factors of cardiopulmonary exercise test (CPET) parameters related to adverse prognostic events within 5 years in patients undergoing percutaneous coronary intervention (PCI) for acute myocardial infarction (AMI), and establish a prediction model for the occurrence of adverse events within 5 years to provide a reference for cardiac rehabilitation training. From August 2015 to December 2021, patients who underwent PCI for AMI and completed CPET within 1-2 weeks after surgery before discharge from the Department of Cardiovascular Medicine of Zhengzhou Central Hospital Affiliated to Zhengzhou University, Henan Provincial Hospital of Traditional Chinese Medicine, and Anyang District Hospital were selected as participants. Univariate and multivariate analyses were used to screen for independent risk factors associated with 5-year adverse events. Feature importance was interpreted using SHapley Additive exPlanations (SHAP), and a logistic regression model was established for prediction. A receiver operating characteristic (ROC) curve was constructed to evaluate the performance of the prediction model. Calibration was assessed by the Hosmer-Lemeshow test and the calibration curve. In total, 375 patients met the inclusion criteria. Based on whether adverse events occurred during the 5-year follow-up period, the patients were divided into two groups: the event group (n = 53) and the non-event group (n = 322). Peak oxygen uptake (peakVO2), carbon dioxide ventilation equivalent slope (VE/VCO2slop), and peak end-tidal carbon dioxide partial pressure (PETCO2) were three independent risk factors for re-acute myocardial infarction (re-AMI), heart failure (HF), and even death after PCI for AMI (P < 0.05). The SHAP plots demonstrated that the significant contributors to model performance were related to peakVO2, VE/VCO2slop, and PETCO2. The risk of adverse events was significantly reduced when the peakVO2 was ≥ 20 mL/kg/min and the VE/VCO2slop was < 33. The ROC curves of the three models were drawn, including the no-event and event groups, re-AMI group, and HF group, which performed well, with AUC of 0.894, 0.760, and 0.883, respectively. The Hosmer-Lemeshow test showed that the three models were a good fit (P > 0.05). The calibration curve of the three models was close to the ideal diagonal lines. CPET parameters can predict the prognosis of adverse events within 5 years after PCI in patients with AMI and provide a theoretical basis for cardiac rehabilitation training.


Asunto(s)
Prueba de Esfuerzo , Infarto del Miocardio , Intervención Coronaria Percutánea , Humanos , Intervención Coronaria Percutánea/efectos adversos , Masculino , Femenino , Persona de Mediana Edad , Infarto del Miocardio/fisiopatología , Infarto del Miocardio/diagnóstico , Pronóstico , Prueba de Esfuerzo/métodos , Anciano , Factores de Riesgo , Curva ROC
2.
PLoS One ; 19(5): e0303148, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38753690

RESUMEN

BACKGROUND: As a geriatric syndrome, sarcopenia has a high prevalence in the old population and represents an impaired state of health with adverse health outcomes. A strong clinical interest in its relationship with venous thromboembolism (VTE), which is a complex trait disease with a heterogeneous annual incidence rate in different countries, has emerged. The relationship between sarcopenia and venous thromboembolism has been reported in observational studies but the causality from sarcopenia to VTE remained unclarified. We aimed to assess the causal effect of sarcopenia on the risk of VTE with the two-sample Mendelian randomization (MR) method. METHODS: Two sets of single-nucleotide polymorphisms (SNPs), derived from two published genome-wide association study (GWAS) meta-analyses and genetically indexing muscle weakness and lean muscle mass separately, were pooled into inverse variance weighted (IVW), weighted median and MR-Egger analyses. RESULTS: No evidence was found for the causal effect of genetically predicted muscle weakness (IVW: OR = 0.90, 95% CI = 0.76-1.06, p = 0.217), whole body lean mass (IVW: OR = 1.01, 95% CI = 0.87-1.17, p = 0.881) and appendicular lean mass (IVW: OR = 1.13, 95% CI = 0.82-1.57, p = 0.445) on the risk of VTE. However, both genetically predicted whole-body lean mass and appendicular lean mass can causally influence diabetes mellitus (IVW of whole-body lean mass: OR = 0.87, 95% CI = 0.78-0.96, p = 0.008; IVW of appendicular lean mass: OR = 0.71, 95% CI = 0.54-0.94, p = 0.014) and hypertension (IVW of whole-body lean mass: OR = 0.92, 95% CI = 0.87-0.98, p = 0.007; IVW of appendicular lean mass: OR = 0.84, 95% CI = 0.73-0.96, p = 0.013). CONCLUSIONS: Genetically predicted sarcopenia does not causally influence VTE directly, but it might still have an indirect effect on VTE incidence via diabetes mellitus and hypertension.


Asunto(s)
Estudio de Asociación del Genoma Completo , Análisis de la Aleatorización Mendeliana , Polimorfismo de Nucleótido Simple , Sarcopenia , Tromboembolia Venosa , Humanos , Sarcopenia/genética , Sarcopenia/epidemiología , Sarcopenia/complicaciones , Tromboembolia Venosa/genética , Tromboembolia Venosa/etiología , Tromboembolia Venosa/epidemiología , Factores de Riesgo
3.
Artículo en Inglés | MEDLINE | ID: mdl-38592862

RESUMEN

Polymer nanofibers have established a robust foundation and possess immense potential in various emerging fields such as sensors and biotechnology. In this study, aqueous dispersions of aramid nanofibers (ANFs) were successfully prepared by using tannic acid (TA). Morphological analysis revealed that TA effectively prevented self-aggregation of ANFs, and preserved the nanofiber structure during TA-assisted solvent exchange. Subsequently, the ANF and TA/ANF films were fabricated using casting and vacuum-assisted filtration techniques. Notably, the tensile strength of the casting TA/ANF film reached 393.8 MPa, exhibiting a remarkable improvement of 41.3% compared to that of the pure ANF film. These exceptional mechanical properties can be attributed to the well-dispersed nanostructures, hydrogen-bonding interactions, zigzag structures, and fiber-bridging effects. Furthermore, the TA/ANF film demonstrated superior ultraviolet (UV) shielding capabilities, visible transparency properties, and excellent resistance to chemical reagents. The above-mentioned interesting findings demonstrate its potential as a nanofiber-reinforced material for poly(vinyl alcohol) (PVA) composites.

4.
ACS Appl Mater Interfaces ; 15(47): 55150-55162, 2023 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-37967290

RESUMEN

The integration of ultraflexible and mechanically robust films with electric heaters and camouflage technology provides a promising platform for the development of wearable devices, especially for aerospace and military applications. Herein, we present a facile and efficient one-step vacuum-assisted filtration method for fabricating Janus films based on aramid nanofibers (ANF) and Ti3C2Tx (MXene). The ANF/MXene nanocomposite film exhibits remarkable properties, including high conductivity (23809.5 S/m), excellent mechanical strength (102.54 MPa), and outstanding thermal stability (575 °C). Most notably, the Janus ANF/MXene composite film demonstrates superior Joule heating performance with a low driving voltage (1-5 V), high heating temperature (30-276 °C), and rapid response time (within 5 s). Additionally, the film exhibits effective thermal camouflage (72 °C for objects with temperatures above 163 °C) and excellent electromagnetic interference shielding properties (SSE/t = 32475.6 dB cm2/g). These results demonstrate that Janus ANF/MXene films possess a unique combination of thermal camouflage, Joule heating, and electromagnetic interference shielding properties, making them highly promising for wearable devices, high-performance electrical heating, infrared stealth, and security protection applications.

5.
Int J Biol Macromol ; 241: 124657, 2023 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-37119893

RESUMEN

Electrochromic materials have attracted extensive attention recently due to their versatile applications in smart windows, displays, antiglare rearview mirrors, and so on. Herein we report a new electrochromic composite prepared from collagen and polyaniline (PANI) through a self-assembly assisted co-precipitation method. The introduction of hydrophilic collagen macromolecules into PANI nanoparticles makes the collagen/PANI (C/PANI) nanocomposite obtain excellent dispersibility in water, which provides good environmental-friendly solution processability. Furthermore, the C/PANI nanocomposite exhibits excellent film-forming properties and adhesion to the ITO glass matrix. The resulting electrochromic film of the C/PANI nanocomposite displays significantly improved cycling stability compared with the pure PANI film after 500 coloring-bleaching cycles. On the other hand, the composite films also exhibit yellow, green and blue polychromatic properties at different applied voltages and high average transmittance at the bleaching state. The C/PANI electrochromic material illustrates scaling potential for the application of electrochromic devices.


Asunto(s)
Compuestos de Anilina , Nanocompuestos , Colágeno , Ácido Hipocloroso , Compuestos de Sodio
6.
Biotechnol Genet Eng Rev ; : 1-20, 2023 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-36823969

RESUMEN

This research is to test whether the combination model (CM) (combining cardiac rehabilitation (CR) with other cardiovascular medical services) impact patients' readmissions, physical and psychological outcomes. We found that CM significantly enhances patients' exercise ability and psychological condition and reduces readmission rates after discharged from the hospital, compared to patients that are admitted to non-CM. Departments' physical resources weaken the impact of CM on patients' physical outcomes and readmission rates while increasing patients' psychological conditions. Human resources strengthen the impact of CM on patients' readmission rates while reducing the impact on patients' physical outcomes. Our results provide empirical evidence for hospital resource constraints puzzle and reallocation. These results provide a possibility of introducing CM as a way to deal with CR implementing challenges.


What we already knowThe impact of service models (such as healthcare integrations) on hospital- and patient-level outcomes has been empirically verified.Scholars demonstrate that cardiac rehabilitation (CR) can improve secondary prevention outcomes with comprehensive risk reduction and long-term care, but there are still barriers and challenges to implement CR.Prior studies show hospital resources have significant impacts on practices implementing, patients' satisfaction and readmission rates.What this article addsWe extend the research on service providing field. Patients choose combination model (CM), which significantly enhances their exercise ability and psychological condition. Their readmission rates are also reduced.Higher departments' physical resources diminish the reduction of patients' admission rates, and human resources strengthen the reduction of patients' readmission rates.These results suggest that CM benefits patients' outcomes, and department resources favor certain outcomes.

7.
J Mol Graph Model ; 100: 107663, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32659629

RESUMEN

A series of novel antifolates (32 compounds) were used to study the interactions with folate receptors α and ß. The compounds had different sizes of methyl (-CH3), carboxyl (-COOH), hydroxyl (-OH), and amino groups (-NH2). The binding properties of the complexes were studied by molecular docking, molecular dynamic (MD) simulations, and MM/PBSA free energy calculations. The docked binding energies and modes were analyzed to identify compounds with good recognition of FRα from FRß. The stable conformers, root mean square displacement, root mean square fluctuation free binding energy, and contribution of residues to the binding energy of the complexes were further analyzed to illustrate the interactions between the novel compounds and folate receptors. The data show that introducing long functional groups in folate will increase the binding affinity with FRα but will decrease the binding affinity with FRß. The results provide a strategy for the design of novel antifolates targeted to FRα.


Asunto(s)
Antagonistas del Ácido Fólico , Ácido Fólico , Antagonistas del Ácido Fólico/farmacología , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular
8.
ACS Appl Mater Interfaces ; 12(30): 33989-33998, 2020 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-32610011

RESUMEN

Poly(vinylidene fluoride) (PVDF)-based piezoelectric materials are promising candidates for sensors, transducers, and actuators, due to several distinctive characteristics such as good flexibility, easy processability, and high mechanical resistance. In the present work, PVDF-based nanocomposites loaded with BaTiO3 nanoparticles (NPs) of various weight fractions were prepared by the electrospinning technique and used for the fabrication of a flexible piezoelectric pressure tactile sensor (PPTS). The addition (5, 10, and 20 wt %) of piezoelectric BaTiO3 NPs improves the piezoelectric performance, especially the ß phase crystals of PVDF/BaTiO3 (10 wt %) nanocomposites that can reach 91.0%. In addition, the mechanical strength of PVDF/BaTiO3 nanocomposites is up to 26.7 MPa, which is an increase of 66% compared to neat PVDF. It should be emphasized that the elongation at break continuously increases from 71% to 153% with increasing BaTiO3 NPs. More importantly, the PPTS (piezoelectric pressure tactile sensor) with the combination of electrospun PVDF/BaTiO3 nanocomposite membranes and polydimethylsiloxane (PDMS) displays excellent flexibility and linear response to external mechanical force. The flexible PPTS devices capable of detecting different music sounds have potential uses in wide fields, such as voice recognition, speech therapy, and ultrasound imaging.

9.
Chemistry ; 25(41): 9665-9669, 2019 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-31066939

RESUMEN

Two base-promoted quadruple domino reactions between thioaurones and allylic phosphonium salts have been developed to synthesize benzothiophene-fused oxa[6.6.5]tricyclic skeletons in moderate to good yields with excellent stereoselectivity and broad functional-group tolerance. This is a simple and useful protocol for the rapid construction of the umbrella-like oxa[6.6.5]tricyclic skeleton.

10.
ACS Appl Mater Interfaces ; 11(24): 21610-21618, 2019 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-31117468

RESUMEN

Billions of tonnes of thick waste streams with highly concentrated colloidal suspensions from different origins have accumulated worldwide, exampled as over 220 km2 mature fine tailings (MFT) from oil sands production in north Alberta. Current treatment technologies are limited by slow yet insufficient water release and sludge consolidation. Herein, a self-healing composite hydrogel system is designed to convert concentrated aqueous colloidal suspensions (e.g., MFT with colloidal solid content >30 wt %) into a dynamic double cross-linked network for rapid dewatering and consolidation. The resultant composite hydrogel demonstrates an excellent dewatering performance so that over 50% of water could be rapidly released within 30 min by vacuum filtration. Furthermore, the formed infinite cross-linked network with self-healing ability can effectively trap fine particles of all sizes and capture small flocs during mechanical mixing, thereby enabling a low solid content at the ppm level in the released water. This new strategy outperforms all the previously reported treatment methods; under mechanical compression, over 80% of water is removed from the MFT, thereby generating a stackable material with >70 wt % solids within an hour. These results demonstrate a highly effective approach and provide insight into the development of advanced materials to tackle the challenging environmental slurry issues.

11.
J Biomed Nanotechnol ; 15(5): 857-877, 2019 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-30890220

RESUMEN

The possibility of composite nanofibers being able to regenerate bone is an attractive proposition. Adenosine, which occurs naturally in humans, has been shown to promote the osteogenic differentiation of mesenchymal stem cells (MSCs) and osteoprogenitor cells. In this study, electrospun nanofibers of poly(3-hydroxybutyrate-co-3-hydroxybutyrate) (PHBV) doped with adenosine were demonstrated to exhibit excellent capacity for bone regeneration, after optimization of the electrospinning process. The biomechanical properties, hydrophilicity, biocompatibility, cellular performance of the nanofibers and adenosine release profile from the composite nanofibers were evaluated. The osteogenic capacity of the composite nanofibers in vitro and in vivo was systematically studied. Electrospun adenosine/PHBV nanofibers demonstrated excellent tissue biocompatibility. In addition, adenosine-loaded/PHBV electrospun nanofibers exhibited substantial bone regeneration capacity in vitro and in critical-sized rabbit cranial defects in vivo, which was greater than that of bone marrow MSC (BMSC)-loaded/PHBV electrospun nanofibers. Additionally, BMSCs/PHBV electrospun nanofibers required culture with BMSCs for a period of time prior to surgery, whereas the adenosine/PHBV electrospun nanofibers could be implanted directly. To date, there is seldom no studies have evaluated the capability of bone regeneration of electrospun nanofibers doped with adenosine. Using a simple fabrication process and with a structure similar to that of natural extracellular matrix (ECM), electrospun adenosine/PHBV nanofibers exhibited excellent biocompatibility and osteogenic capacity. In addition, adenosine is inexpensive, straightforward to obtain and store and so holds huge practical potential in bone tissue engineering applications.


Asunto(s)
Células Madre Mesenquimatosas , Nanofibras , Adenosina , Animales , Regeneración Ósea , Proliferación Celular , Osteogénesis , Poliésteres , Conejos , Ingeniería de Tejidos , Andamios del Tejido
12.
Spectrochim Acta A Mol Biomol Spectrosc ; 213: 263-271, 2019 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-30703709

RESUMEN

Filamentous bacteria, particularly Microthrix parvicella, are mainly responsible for bulking or foaming of activated sludge. Based on the affinity of M. parvicella to the hydrophobic characteristics of long-chain fatty acids, a novel bisoctyl rhodamine B (BORB) and a novel fluorescence resonance energy transfer (FRET) complex probe were prepared herein to study their properties. When the FRET probe was used in in situ activated sludge, M. parvicella was clearly labeled at 20 nmol/L, which was a reduction of 50 times compared to that of the BORB (1 µmol/L) alone and 500 times compared to the carbazole-quinoline probe reported previously. Compared with fluorescence in situ hybridization, M. parvicella could be clearly labeled using BORB and the FRET probe in situ without requiring complicated pretreatments (i.e., shock and broken process, fixed sample, digestion, and lysozyme treatment). This study discusses the facile approach developed for labeling M. parvicella in early warning expansion, thereby inhibiting and controlling sludge bulking in situ.


Asunto(s)
Actinobacteria/metabolismo , Transferencia Resonante de Energía de Fluorescencia , Colorantes Fluorescentes/química , Rodaminas/química , Coloración y Etiquetado , Actinobacteria/citología , Rodaminas/síntesis química , Aguas del Alcantarillado/microbiología , Solventes/química , Espectrofotometría Ultravioleta
13.
J Mol Graph Model ; 87: 121-128, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30537642

RESUMEN

Twenty novel compounds with different functional groups (-COOH, -OH, -NH2 and -CH3) were designed to study the interaction mechanism of ligands with folate receptors (FRs). The optimized structure and the dipole moment of the novel compounds were calculated by a density functional tight-binding method (DFTB). The binding mechanism of the compounds with FRs was studied by molecular docking, molecular dynamic (MD) simulations and MM/PBSA free energy calculations. The binding energies, root mean square displacement and root mean square fluctuation of the complexes were analyzed to further illustrate the effect of the functional groups. The functional groups play important roles in stabilizing the bound complexes. Compared to other groups, -OH is more stably linked with the compound. These data provide a theoretical basis for the design of novel compounds targeted with FRs.


Asunto(s)
Receptores de Folato Anclados a GPI/química , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Receptores de Folato Anclados a GPI/antagonistas & inhibidores , Ácido Fólico/química , Ligandos , Estructura Molecular , Unión Proteica , Conformación Proteica , Relación Estructura-Actividad
14.
ACS Appl Mater Interfaces ; 10(49): 42992-43002, 2018 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-30456954

RESUMEN

Strengthened poly(lactic acid) (PLA)-based materials with improved mechanical performance and improved thermal resistance, notably, are prepared by introducing stereocomplex crystallite (SC), an ideal filler, into the materials. Owing to the intermolecular hydrogen bond among the stereoisomer chains, the melting point of the special crystallite is up to 200 °C, which is 50 °C higher than the isostatic crystallite. The modulus of the PLA-based materials can be enhanced to several 100 MPa because of the integrated polymer chain arrangement. In this study, we electrospun hybrid nanofibers consisted of PLA stereoisomers and induced the stereocomplex crystallization under a mild condition (65 °C for 1 h). The mild warming is favorable for the protection of chlorogenic acid (CA) that was selected as the antibacterial agent. Both of Gram-positive and Gram-negative bacteria were efficiently cleared away using the warmed nanofibers that released CA rapidly within just a few hours. Used as filters, the SC electrospinning membrane also presented a potent filtering effect, leaving no bacteria retained in the filtrates. Attributing to SC, the PLA-based nanofibers showed extremely increased melting temperature over 200 °C and improved Young's modulus up to 270.0 MPa. The durable nanofibers prepared in present study are meaningful for enlarging the application of PLA-based materials, for example, as filters, masks, and packages.


Asunto(s)
Antibacterianos/química , Bacterias Gramnegativas/crecimiento & desarrollo , Bacterias Grampositivas/crecimiento & desarrollo , Nanofibras/química , Poliésteres/química
15.
J Mol Graph Model ; 85: 40-47, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-30055477

RESUMEN

Nine novel fluorescent antifolates, 1-9, were designed and docked with FRα and FRß. The binding energies of the bound complexes were determined by molecular docking and MM-PBSA studies. The structural properties of the complexes FR-FOL, FR-7, FR-8 and FR-9 were analyzed in detail via molecular docking and molecular dynamics studies. We further calculated the root mean square displacement and root mean square fluctuation of the bound complexes using molecular dynamics simulations. Since compounds 7, 8 and 9 are promising candidate in distinguishing FRα from FRß, the hydrogen bond properties of complexes FRα-7, FRα-8 and FRα-9 were studied by a dispersion complemented density functional tight-binding method. The purpose of this study is to provide a rationale for the design of novel fluorescent antifolates targeted with FRα and FRß.


Asunto(s)
Teoría Funcional de la Densidad , Receptor 1 de Folato/química , Antagonistas del Ácido Fólico/química , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Receptor 1 de Folato/antagonistas & inhibidores , Antagonistas del Ácido Fólico/farmacología , Enlace de Hidrógeno , Conformación Molecular , Estructura Molecular , Relación Estructura-Actividad Cuantitativa
16.
Oncol Rep ; 40(3): 1243-1250, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29956815

RESUMEN

Kank1, an important member of the Kank gene family, plays an important role in the development of many malignant tumors. As a brand new tumor-suppressor gene, the expression of Kank1 gene has been revealed to be downregulated or absent in many malignant tumors. However, there is no study concerning the specific role of Kank1 in the development and progression of lung cancer. In the present study, we found that the Kankl gene was significantly downregulated in human lung cancer and lung cancer cells. When the Kankl gene was upregulated, we found that the proliferation of lung cancer cells was significantly inhibited, the cells were arrested in the G0/G1 phase, the apoptosis of cells was observed, the expression of the caspase family of genes was altered with mainly the activation of caspase-3 and -9, and Bcl-2/Bax ratio was significantly imbalanced. In addition, we also found that upregulation of the Kankl gene resulted in the inhibition of tumor cell invasion and metastasis. Concurrently, in vivo nude mice experiments also confirmed that upregulation of Kank1 expression led to reduced tumor formation in nude mice and significantly reduced tumor volume. These results revealed that upregulation of the Kankl gene inhibited the progression of lung cancer both in vitro and in vivo, and its mechanism was closely related to cell apoptosis as well as tumor invasion and metastasis.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Movimiento Celular , Proliferación Celular , Regulación Neoplásica de la Expresión Génica , Neoplasias Pulmonares/patología , Proteínas Supresoras de Tumor/metabolismo , Proteínas Adaptadoras Transductoras de Señales , Animales , Apoptosis , Biomarcadores de Tumor/genética , Ciclo Celular , Proteínas del Citoesqueleto , Progresión de la Enfermedad , Humanos , Técnicas In Vitro , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Masculino , Ratones , Ratones Desnudos , Invasividad Neoplásica , Células Tumorales Cultivadas , Proteínas Supresoras de Tumor/genética , Ensayos Antitumor por Modelo de Xenoinjerto
17.
Spectrochim Acta A Mol Biomol Spectrosc ; 191: 180-188, 2018 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-29032342

RESUMEN

As its significant role, the selective recognition of G-quadruplex with specific structures and functions is important in biological and medicinal chemistry. Carbazole derivatives have been reported as a kind of fluorescent probe with many excellent optical properties. In the present study, the fluorescence of the dye (carbazole TO) increased almost 70 fold in the presence of bcl-2 2345 G4 compared to that alone in aqueous buffer condition with almost no fluorescence and 10-30 fold than those in the presence of other DNAs. The binding study results by activity inhibition of G4/Hemin peroxidase experiment, NMR titration and molecular docking simulation showed the high affinity and selectivity to bcl-2 2345 G4 arises from its end-stacking interaction with G-quartet. It is said that a facile approach with excellent sensitive, good selectivity and quick response for bcl-2 2345 G-quadruplex was developed and may be used for antitumor recognition or antitumor agents.


Asunto(s)
Carbazoles/química , ADN/química , Colorantes Fluorescentes/química , G-Cuádruplex , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Secuencia de Bases , Dicroismo Circular , Humanos , Conformación Molecular , Simulación del Acoplamiento Molecular , Espectroscopía de Protones por Resonancia Magnética , Teoría Cuántica , Espectrometría de Fluorescencia , Factores de Tiempo
18.
RSC Adv ; 8(62): 35855-35862, 2018 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-35547900

RESUMEN

Microthrix parvicella (M. parvicella) is a filamentous bacterium that induces bulking in activated sludge. Here, we used the affinity of long-chain fatty acids (LCFA) for M. parvicella to create a novel fluorescent probe of carbazole modified by LCFA. The structure was characterized by 1H NMR spectroscopy and mass spectrometry. The spectral properties, photostability, and hydrophobic properties of the probe were also characterized. Fluorescent-labeling results showed that it can label M. parvicella in situ and could be biodegraded via metabolism. The stable docking mode of carbazole probes with different fatty acid chains and lipases was also docked by the density functional tight-binding (DFTB) method.

19.
ACS Appl Mater Interfaces ; 9(19): 16426-16434, 2017 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-28447775

RESUMEN

On the basis of nanocellulose obtained by acidic swelling and ultrasonication, rodlike nanocellulose/polyaniline nanocomposites with a core-shell structure have been prepared via in situ polymerization. Compared to pure polyaniline, the nanocomposites show superior film-forming properties, and the prepared nanocomposite films demonstrate excellent electrochemical and electrochromic properties in electrolyte solution. Nanocomposite films, especially the one prepared with 40% polyaniline coated nanocomposite, exhibited faster response time (1.5 s for bleaching and 1.0 s for coloring), higher optical contrast (62.9%), higher coloration efficiency (206.2 cm2/C), and more remarkable switching stability (over 500 cycles). These novel nanocellulose-based nanorod network films are promising novel electrochromic materials with excellent properties.

20.
J Fluoresc ; 26(4): 1511-20, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27307022

RESUMEN

A novel fluorescent dye, 1-(2-hydroxyethyl)-4-((E)-2-(3-benzothiazol-2yl-9-ethyl-carbazole-3yl)vinyl) pyridinium bromide, was synthesized for determination of protein and its structure was characterized by (1)H NMR. Photophysics of the new probe in different solvents has been delineated in this paper, the new fluorescent molecular dye exhibited a large stokes-shifted and fluorescence quantum yields in organic solvent. The photostability and thermostability of the new dye were also studied and the results suggested the stable was excellent. The interactions of the dye with bovine serum albumin (BSA) , Human serumal bumin (HSA) and calf thymus deoxyribonucleic acid (ctDNA) were studied by fluorescence and absorption spectroscopy. The binding constant for BSA, HSA and DNA were calculated to be 8.91 × 10(7), 1.86 × 10(6) and 2.9 × 10(4), respectively. The experimental results indicated a potential value of the new dye for biomarker.


Asunto(s)
Benzotiazoles/química , Benzotiazoles/síntesis química , Compuestos de Piridinio/química , Compuestos de Piridinio/síntesis química , Albúmina Sérica Bovina/análisis , Albúmina Sérica Bovina/química , Albúmina Sérica Humana/análisis , Albúmina Sérica Humana/química , Animales , Bovinos , Técnicas de Química Sintética , ADN/análisis , ADN/química , Colorantes Fluorescentes/síntesis química , Colorantes Fluorescentes/química , Humanos , Temperatura
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