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1.
Talanta ; 238(Pt 2): 123070, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34808565

RESUMO

Molecularly imprinted polymers endowed with photo-luminescent properties have attracted wide research interest in many fields such as biological analysis and diseases diagnosis. Herein, we illustrate a versatile method for the construction of surface protein-imprinted nanoparticles based on metal coordination and anchored carbon dots (CDs) for enhanced fluorescence detection of the target protein. As the fluorescent nanosupports for surface imprinting, CDs-attached SiO2 nanoparticles were synthesized via thiol-ene click chemistry. With histidine (His)-exposed protein as templates, imprinted nanoshells were formed over the nanosupports via copolymerization of a Cu2+-chelating monomer and an oligo (ethylene glycol) monomer, hence producing high-quality imprinted cavities because of both the relatively strong coordination and inhibited non-specific binding. Using lysozyme as a model His-exposed template, the imprinted nanoparticles showed fluorescence enhancement while binding the target protein, and exhibited significantly increased specific fluorescence response than the controls without the metal coordination. They achieved a high imprinting factor of 5.8 and a low limit of detection of 10.1 nM. Furthermore, such sensors were applied to determine lysozyme in diluted chicken egg-white samples with satisfactory recoveries at three spiking levels ranging from 97.9 to 101.4%. Human serum albumin was also used as another template protein for preliminary confirming the generality of the presented strategy.


Assuntos
Impressão Molecular , Nanoconchas , Pontos Quânticos , Carbono , Humanos , Proteínas de Membrana , Dióxido de Silício
2.
Talanta ; 234: 122690, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34364488

RESUMO

Epitope imprinting has proved to be an effective way for fabricating artificial receptors for protein recognition. Surface imprinting over sacrificial supports is particularly favorable for generating high-quality epitope-imprinted cavities, but obtaining nanomaterials by this way is still a challenge. Herein, we propose a method for the synthesis of oriented surface epitope-imprinted open-mouthed polymer nanocapsules (OM-MIP NCs) by sacrificing asymmetric template-modified Janus nanocores. Amine/aldehyde functionalized SiO2 Janus nanoparticles were prepared via the molten-wax-in-water Pickering emulsion approach, an easy scale-up technique. Epitope templates and vinyl groups were coupled to the aldehyde-bearing major side, whereas polyethylene glycol (PEG) chains were grafted to the amine-modified side. Incomplete imprinted shells were then generated principally on the non-PEGylated side via aqueous precipitation polymerization, hence affording OM-MIP NCs after etching the SiO2 nanocores. With a C-terminus nonapeptide of bovine serum albumin (BSA) chosen as a model epitope and polymerizable carbon dots added to the pre-polymerization solution, fluorescent OM-MIP NCs were synthesized for sensing of BSA. Such NCs reached maximal fluorescent response within 15 min, greatly faster than the closed imprinted NCs within 130 min, proving good accessibility of their inner-surface imprinted cavities thanks to the open mouths. Furthermore, they showed excellent target protein detection performance, with an imprinting factor of 7.8, a limit of detection of 43.8 nM and a linear range of 0.2-6 µM. The recoveries in bovine serum samples at four spiking levels ranged from 99.2 to 107.2%, with relative standard deviations of 1.2-5.9%.


Assuntos
Impressão Molecular , Nanocápsulas , Animais , Bovinos , Epitopos , Polímeros , Soroalbumina Bovina , Dióxido de Silício
3.
J Phys Chem A ; 125(19): 4126-4132, 2021 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-33961432

RESUMO

Since the discovery of metal-doped boron clusters attracted great significance to create a new class of materials, research interests have been directed to chemical bonding and structural evolution of lanthanide boride clusters. Here, we perform an extensive ground-state structure search for the CeBn and CeBn- clusters in the size range from 9 to 18 using the Crystal structure AnaLYsis by Particle Swarm Optimization method and density functional theory optimization. It is found that the ground-state structures in both neutral and anionic series possess half-sandwich geometry. The host boron moiety in neutral series has a tendency to form borophene-like geometry. The pentagonal and hexagonal holes are more common in the larger anionic CeBn- series. The theoretical photoelectron spectroscopy has been simulated by applying time-dependent density functional theory calculations. The neutral CeB14 cluster is identified as a magic cluster on the basis of its robust relative stability with respect to its neighbors. Electronic structure and chemical bonding analyses reveal that the CeB14 cluster possesses a large HOMO-LUMO gap and enhanced stability with strong delocalized π and δ bonding via interactions between the Ce 5d- and B 2p-AOs.

4.
Cardiovasc Ther ; 2019: 8563717, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31772619

RESUMO

Background: Fibrinogen levels have been associated with coronary plaque vulnerability in experimental studies. However, it has yet to be determined if serum fibrinogen levels are independently associated with coronary plaque vulnerability as detected by optical coherence tomography (OCT) in patients with coronary heart disease. Methods: Patients with coronary heart disease (CHD) who underwent coronary angiography and OCT in our department from January 2015 to August 2018 were included in this study. Coronary lesions were categorized as ruptured plaque, nonruptured with thin-cap fibroatheroma (TCFA), and nonruptured and non-TCFA. Presence of ruptured plaque and nonruptured with TCFA was considered to be vulnerable lesions. Determinants of coronary vulnerability were evaluated by multivariable logistic regression analyses. Results: A total of 154 patients were included in this study; 17 patients had ruptured plaques, 15 had nonruptured plaques with TCFA, and 122 had nonruptured plaques with non-TCFA. Results of univariate analyses showed that being male, diabetes, current smoking, high body mass index (BMI), and clinical diagnosis of acute coronary syndrome (ACS) were associated with coronary vulnerability. No significant differences were detected in patient characteristics, coronary angiographic findings, and OCT results between patients with higher and normal fibrinogen. Results of multivariate logistic analyses showed that diabetes and ACS were associated with TCFA, while diabetes, higher BMI, and ACS were associated with plaque rupture. Conclusions: Diabetes, higher BMI, and ACS are independently associated with coronary vulnerability as detected by OCT. Serum fibrinogen was not associated with coronary vulnerability in our cohort.


Assuntos
Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/diagnóstico por imagem , Vasos Coronários/diagnóstico por imagem , Fibrinogênio/análise , Placa Aterosclerótica , Tomografia de Coerência Óptica , Síndrome Coronariana Aguda/sangue , Síndrome Coronariana Aguda/diagnóstico por imagem , Adulto , Idoso , Biomarcadores/sangue , Índice de Massa Corporal , Angiografia Coronária , Doença da Artéria Coronariana/patologia , Vasos Coronários/patologia , Diabetes Mellitus/sangue , Diabetes Mellitus/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Ruptura Espontânea
5.
Phys Chem Chem Phys ; 21(39): 21746-21752, 2019 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-31552405

RESUMO

A theoretical study of geometrical structures and electronic properties of niobium-doped boron clusters is performed using the CALYPSO approach for the global minimum search followed by density functional theory calculations. It is found that the global minima obtained for the neutral clusters correspond to the half-sandwich structures at n = 10-17 and the tubular-type structures at n = 18-20. The geometrical patterns in the anion series are more complex. The geometries undergo a transformation from the wheel-like structure of NbB10- to the half-sandwich ones beginning at n = 11 and finally to the drum-shaped structures at n ≥ 18. A fascinating NbB12- cluster is uncovered by our structural search, which shows robust stability and can be considered as a new member of the half-sandwich transition metal doped boron clusters. The chemical bond analysis indicates that the high stability is due to the strong interactions between the Nb atom and the B12 host as well as to the strong B-B covalent bonds. Our study will enrich the database of geometrical structures of transition metal doped boron clusters and will stimulate future synthesis of boron-based nanomaterials.

6.
J Phys Condens Matter ; 31(48): 485302, 2019 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-31412328

RESUMO

Doping of boron-based materials with transition metal atoms allows one to tune or modify the properties and structure of the materials. In this work, an extensive search for the global minima on potential energy surfaces of ScB n and ScB[Formula: see text] clusters has been performed using the CALYPSO method. The structural evolution of scandium doped boron clusters of this range is found to proceed in three steps; namely, the formation of half-sandwich type structures is followed by the formation of drum-like structures with the Sc atom located at the center and terminates with the cage-like structures. It is also found that highly symmetrical geometric structures are more common for the smaller size range of [Formula: see text]. The neutral ScB13 cluster is identified as magic on the basis of an analysis of relative stabilities in the ScB n series. Our analysis of chemical bonding has shown that the stability of this cluster is mainly due to the formation of several delocalized [Formula: see text]-bonding molecular orbitals composed of Sc 3d and B 2s atomic orbitals. These bonds appear to be responsible for the enhanced stability of ScB13 with respect to other Sc-doped boron clusters.

7.
BMC Cardiovasc Disord ; 19(1): 128, 2019 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-31142268

RESUMO

BACKGROUND: The association between mean platelet volume (MPV) and coronary plaque vulnerability in patients with non-ST-elevation ACS (NSTE-ACS) has not been investigated. We performed a retrospective study to evaluate the association between MPV and plaque vulnerability using optical coherence tomography (OCT). METHODS: Consecutive NSTE-ACS patients who underwent pre-intervention OCT examination in our center were included in this study. Features of coronary plaques in the culprit arteries were classified as rupture, nonrupture with thin-cap fibroatheroma (TCFA), and nonrupture and non-TCFA. ROC analyses were used to determine the predictive efficacy of MPV for plaque rupture, and multivariate logistic regression analysis was performed to evaluate the potential independent predictors of plaque vulnerability. RESULTS: Overall, 94 patients were included in this study. We identified 17 patients with plaque rupture, 10 with nonrupture with TCFA, and 67 with nonrupture and non-TCFA. ROC analyses showed that MPV ≥ 10.5 fL was predictive of plaque rupture in NSTE-ACS patients. Univariate analyses indicated that patients with higher MPV (≥ 10.5 fL) had higher body mass index and poorer lipid profiles compared to those with lower MPV. Moreover, those with higher MPV had higher incidences of plaque rupture and thrombosis (both P < 0.05). Results of multivariate analyses showed that diabetes and higher platelet distribution width (PDW) were independent risk factors of TCFA (P = 0.032 and 0.046, respectively), while diabetes, higher BMI, higher PDW, and higher MPV were independent determinants of plaque rupture in our cohorts (P all < 0.05). CONCLUSIONS: Higher MPV is independently associated with higher risk of plaque rupture as evidenced by OCT in our cohort of NSTE-ACS patients.


Assuntos
Doença da Artéria Coronariana/diagnóstico por imagem , Vasos Coronários/diagnóstico por imagem , Volume Plaquetário Médio , Infarto do Miocárdio sem Supradesnível do Segmento ST/diagnóstico por imagem , Placa Aterosclerótica , Tomografia de Coerência Óptica , Adulto , Idoso , Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/patologia , Vasos Coronários/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio sem Supradesnível do Segmento ST/sangue , Infarto do Miocárdio sem Supradesnível do Segmento ST/patologia , Valor Preditivo dos Testes , Prognóstico , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Ruptura Espontânea
8.
Biomed Res Int ; 2019: 9602783, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30984786

RESUMO

Background: Gamma-glutamyl transferase (GGT) has been detected in coronary plaques. However, the association between serum GGT levels and coronary atherosclerotic plaque vulnerability in patients with coronary artery disease (CAD) as detected by optical coherence tomography (OCT) has not been investigated. Methods: We performed a retrospective study of consecutively enrolled CAD patients undergoing preintervention OCT examination during coronary angiography. Plaque vulnerability was defined as the presence of ruptured plaques or thin-cap fibroatheroma (TCFA) upon OCT. The association between serum GGT levels and coronary plaque vulnerability was evaluated using multivariate logistic regression analysis. Results: A total of 142 patients were included in our analysis. OCT examination detected ruptured plaques in 16 patients, nonruptured plaques with TCFA in 17 patients, and nonruptured plaques and non-TCFA in 109 patients. Univariate analyses showed that gender, diabetes, Apolipoprotein A1 (ApoA1) and high-density lipoprotein cholesterol (HDL-c), and diagnosis of acute coronary syndrome (ACS) were associated with plaque vulnerability (P all < 0.05). Patients grouped according to serum GGT tertiles did not differ statistically in baseline characteristics or OCT findings. Results of multivariate logistic analyses showed that diabetes and diagnosis of ACS were associated with plaque rupture and TCFA (P < 0.05). Conclusions: GGT serum levels were not associated with OCT detected coronary vulnerability in our cohort of CAD patient.


Assuntos
Doença da Artéria Coronariana/sangue , Placa Aterosclerótica/patologia , Tomografia de Coerência Óptica , gama-Glutamiltransferase/sangue , Síndrome Coronariana Aguda/sangue , Síndrome Coronariana Aguda/diagnóstico por imagem , Síndrome Coronariana Aguda/patologia , Idoso , Apolipoproteína A-I/sangue , HDL-Colesterol/sangue , Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/patologia , Vasos Coronários/diagnóstico por imagem , Vasos Coronários/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Placa Aterosclerótica/diagnóstico por imagem , Estudos Retrospectivos
9.
Biosci Rep ; 39(4)2019 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-30910844

RESUMO

The acute coronary syndrome (ACS) is a complex disease where genetic and environmental factors are involved. NF-κB, a central regulator of inflammation, is involved in various inflammatory diseases. The aim of the present study was to explore the association between NFKB1 gene rs28362491 (-94ATTGins/del) polymorphism and ACS. A total of 778 ACS patients and 1112 healthy subjects were included in our study. The TaqMan SNP genotyping assays was used to analyze the rs28362491 polymorphism. The lesion extent of coronary artery was assessed by Gensini Score and lesion vessel number in ACS patients. For total and males, the frequencies of the mutant DD genotype and D allele were significantly higher in ACS patients than that in control subjects (total: DD genotype: 18.0 vs 14.1%, P=0.009, D allele: 43.0 vs 37.9%, P=0.002, males: DD genotype: 20.6 vs 15.3%, P=0.042, D allele: 44.2 vs 38.8%, P=0.013). After multivariate logistic regression analysis, we found that individuals with mutant DD genotype had 1.329-fold higher risk of ACS compared with individuals with ID and II genotypes. Moreover, ACS patients with DD genotype were worse stenosis of coronary artery compared with patients carrying II or ID genotype. In conclusion, our study demonstrated that the mutant DD genotype of NFKB1 gene was associated with the risk and severity of ACS in Han population in Xinjiang, northwest of China.


Assuntos
Síndrome Coronariana Aguda/genética , Subunidade p50 de NF-kappa B/genética , Polimorfismo de Nucleotídeo Único , Síndrome Coronariana Aguda/epidemiologia , Idoso , China/epidemiologia , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade
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