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1.
J Cell Physiol ; 235(12): 9370-9377, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32346889

RESUMO

The aim is to investigate the correlation between computed tomography (CT) features and insulin resistance levels in patients with type 2 diabetes mellitus (T2DM) complicated with primary pulmonary tuberculosis (PTB). Nearly, 268 untreated PTB patients complicated with T2DM were divided into two groups according to the optimal cutoff value of HOMA-IR score for the Chinese population: HOMA-IR ≤ 2.69 (Group I: 74 patients), >2.69 (Group II: 194 patients). The basic characteristics and changes of CT manifestations were analyzed. In the two groups, the detection rate of large segmented leafy shadow was 39.2% and 78.9%; the air bronchogram sign detection rate was 40.5% and 80.9%; the discovery rate of mouth-eaten cavity was 33.8% and 73.7%; the thin-walled cavity detection rate was 2.7% and 16.0%; the rate of multiple cavities was 35.1% and 69.6%; and bronchial tuberculosis was found in 4.1% and 35.6%, respectively. The detection rates of lesions in Group II were significantly higher than in Group I (p < .05). HOMA-IR was found independently associated with large segmented leafy shadow, air bronchial sign, thin-walled cavity, and bronchial tuberculosis. The level of insulin resistance can effectively reflect the severity of PTB patients with T2DM. CT scan can directly provide image information in clinics. These two examinations can guide clinicians to accurately formulate subsequent treatment plans.


Assuntos
Diabetes Mellitus Tipo 2/complicações , Resistência à Insulina/fisiologia , Tuberculose Pulmonar/complicações , Tuberculose Pulmonar/metabolismo , Adulto , Glicemia/metabolismo , Feminino , Teste de Tolerância a Glucose/métodos , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X/métodos
2.
Environ Sci Technol ; 47(6): 2886-91, 2013 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-23425130

RESUMO

Polyvinyl pyrrolidone polymer (PVP) has been widely applied in biological and medical fields. A few in vitro studies indicated that PVP might cause toxicity. However, the underlying mechanism is poorly understood. In this work, we found that PVP directly induced strand breakages of various DNA molecules, implicating a cleavage activity. Moreover, reactive oxygen species (ROS) scavenging analysis shows that DNA cleavage activity of PVP is not related to ROS-induced oxidation. As revealed by gel electrophoresis and liquid chromatography/mass spectrometry analysis, the major cleavage products of DNA were identified as two purine bases, guanine and adenine, suggesting that PVPs have a novel depurination activity. The selective depurination and DNA cleavage activity of PVPs were further confirmed by studying the interaction of PVP with four nucleosides and four well-designed oligodeoxynucleotides probes containing specific nucleotides. This study may provide insights into PVP-DNA interactions and resultant genotoxicity and may also open a new way for DNA study.


Assuntos
Clivagem do DNA/efeitos dos fármacos , DNA/química , Mutagênicos/toxicidade , Povidona/toxicidade , Purinas/química , Espécies Reativas de Oxigênio/metabolismo , Sequência de Bases , DNA/genética , Modelos Moleculares
3.
Huan Jing Ke Xue ; 42(11): 5193-5200, 2021 Nov 08.
Artigo em Zh | MEDLINE | ID: mdl-34708958

RESUMO

The emission characteristics of VOCs from three typical rubber manufacture industries were studied by GC-MS/FID. Maximum incremental reactivity(MIR) and fractional aerosol coefficient(FAC) were employed to evaluate the ozone formation potential(OFP) and secondary organic aerosol(SOA) formation potential. The results show that the VOC types emitted from the manufacturing of rubber products mainly include alkanes, ketones, aldehydes, alcohols, and benzene series. For traditional rubber products manufactured through rubber mixing and vulcanization, the main pollutants are ketones and alcohols, whereas for production processes involving gluing and painting, the main pollutants belong to the benzene series. In terms of ozone impact, the traditional processes contribute to ozone formation mainly through oxygenated hydrocarbons. In industries that utilize adhesives and paints, the extensive use of these organic solvents lead to a significantly higher contribution of the benzene series than other VOC species to ozone formation; the benzene series account for 82.9% of the total contribution. In terms of SOA impact, the benzene series are the main contributor to SOA, whereas the contribution of VOCs from traditional processes is small; hence, SOA primarily originates from the gluing and painting processes. Therefore, in traditional production of rubber products through rubber mixing and vulcanization, the emission of oxygenated hydrocarbons should be preferentially controlled, whereas for rubber industries utilizing gluing and painting processes, the emission of benzene series should be preferentially controlled.


Assuntos
Poluentes Atmosféricos , Ozônio , Compostos Orgânicos Voláteis , Poluentes Atmosféricos/análise , China , Monitoramento Ambiental , Ozônio/análise , Borracha , Compostos Orgânicos Voláteis/análise
4.
J Agric Food Chem ; 68(14): 4277-4283, 2020 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-32182058

RESUMO

Ochratoxin A (OTA), a common mycotoxin, has attracted great concern as many foodstuffs can suffer from OTA contamination; OTA causes harmful effects on human and animals. Rapid and sensitive detection of OTA is demanded in many fields for agricultural product quality, food safety, and health. Aptamer fluorescence polarization/anisotropy (FP/FA) assays integrate advantages of nucleic acid aptamers (e.g., easy preparation, high stability, and low cost) and FP/FA analysis (e.g., high sensitivity, rapidity, simplicity, and robustness). Here, we report the preparation of lissamine rhodamine B labeled OTA and developed competitive aptamer fluorescence anisotropy (FA) assays for OTA with signal-off or signal-on responses by using this fluorescently labeled probe. In the signal-off FA assay, the binding between the fluorescent probe and aptamer gave a large FA signal due to molecular volume increase, and the fluorescent probe was displaced from the aptamer in the presence of OTA target, causing FA to decrease. To further enhance the FA change in the signal-off assay, large-sized streptavidin was conjugated on the aptamer, and this assay allowed for a detection limit of 2.5 nM and a more remarkable FA decrease. Furthermore, we found that the fluorescent probe could interact with Tween 20, which caused the fluorescent probe to show a higher FA value than that of the aptamer-fluorescent probe complex. A signal-on FA assay was achieved in the binding buffer containing 0.1% Tween 20, with a detection limit of 10 nM. Signal-off and signal-on FA methods both were selective and enabled detection of OTA spiked in red wine samples, showing capability for target analysis in complex sample matrix.


Assuntos
Aptâmeros de Nucleotídeos/química , Corantes Fluorescentes/química , Ocratoxinas/análise , Rodaminas/química , Ligação Competitiva , Técnicas Biossensoriais , Polarização de Fluorescência/métodos , Contaminação de Alimentos/prevenção & controle , Humanos , Limite de Detecção , Polissorbatos/química , Sensibilidade e Especificidade , Estreptavidina/química , Vinho/análise
5.
Electrophoresis ; 29(22): 4454-62, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19035400

RESUMO

Multiple labeling of nucleic acids by intercalative dyes is a promising method for ultrasensitive nucleic acid assays. The properties of the fast dissociation and instability of dye-DNA complexes may prevent from their wide applications in CE-LIF nucleic acid analysis. Here, we describe an optimum CE focusing method by using appropriately paired sample and separation buffers, Tris-glycine buffer and Tris-glycine-acetic acid buffer. The developed method was applied in both uncoated and polyacrylamide coated fused-silica capillary-based CE-LIF analysis while the sample and separation buffers were conversely used. The complexes of intercalative dye benzoxazolium-4-pyridinium dimer and dsDNA were greatly focused (separation efficiency: 1.8 million theoretical plates per meter) by transient isotachophoresis mechanism in uncoated capillary, and moderately focused by transient isotachophoresis in combination of field amplified sample stacking and further stabilized by the paired buffer in polyacrylamide coated capillary. Based on the developed focusing strategy, an ultrasensitive DNA assay was developed for quantitation of calf thymus dsDNA (from 0.02 to 2.14 pM). By the use of an excitation laser power as low as 1 mW, the detection limits of calf thymus dsDNA (3.5 kb) are 7.9 fM in concentration and 2.4x10(-22) mol (150 molecules) in mass. We further demonstrate that the non-gel sieving CE-LIF analysis of DNA fragments can be enhanced by the same strategy. Since the presented strategy can be applied to uncoated and coated capillaries and does not require special device, it is also reasonable to extend to the applications in chip-based CE DNA analysis.


Assuntos
Benzoxazóis/química , DNA/análise , Eletroforese Capilar/métodos , Substâncias Intercalantes/química , Resinas Acrílicas/química , Animais , Soluções Tampão , Bovinos , Celulose/análogos & derivados , Celulose/química , DNA/química , Eletroforese Capilar/instrumentação , Fluorescência , Sensibilidade e Especificidade , Timo/química
6.
Chem Commun (Camb) ; (44): 4614-6, 2007 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-17989809

RESUMO

We have found a new way, a metal-organic coordination gel template method, to generate polymer monoliths with an essentially macropore size, in which the pores are organized spontaneously into continuous networks; furthermore, the resulting macroporous monoliths have potential applications in high-throughput and high-efficiency separation of proteins.


Assuntos
Metais Pesados/química , Metilmetacrilatos/química , Compostos Organometálicos/química , Ácidos Tricarboxílicos/química , Géis/síntese química , Géis/química , Modelos Moleculares , Compostos Organometálicos/síntese química , Tamanho da Partícula , Porosidade , Propriedades de Superfície , Temperatura , Fatores de Tempo
7.
Huan Jing Ke Xue ; 35(7): 2503-7, 2014 Jul.
Artigo em Zh | MEDLINE | ID: mdl-25244830

RESUMO

Volatile organic compounds (VOCs) play an important role in urban air pollution. Activities of industries including the packaging and printing industries are regarded as the major sources. How to select the suitable treating techniques is the major problem for emission control. In this article, based on the VOCs emission characteristics of the packaging and printing industry and the existing treatment technologies, using the analytic hierarchy process (AHP) model, an evaluation system for VOCs selection was established and all the technologies used for treatment were assessed. It showed that the priority selection was in the following order: Carbon Fiber Adsorption-Desorption > Granular Carbon Adsorption-Desorption > Thermal Combustion > Regenerative Combustion > Catalytic combustion > Rotary adsorption-concentration and combustion > Granular Carbon adsorption-concentration and combustion. Carbon Fiber Adsorption-Desorption was selected as the best available technology due to its highest weight among those technologies.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/prevenção & controle , Compostos Orgânicos Voláteis/análise , Gerenciamento de Resíduos/métodos , Adsorção , Carbono , Fibra de Carbono , Catálise , Indústrias
8.
Artigo em Inglês | MEDLINE | ID: mdl-22841745

RESUMO

A DNA aptamer based high-performance affinity chromatography is developed for selective extraction and screening of a basic protein lysozyme. First, a poly(glycidyl methacrylate-co-ethylene dimethacrylate) monolithic column was synthesized in situ by thermally initiated radical polymerization, and then an anti-lysozyme DNA aptamer was covalently immobilized on the surface of the monolith through a 16-atom spacer arm. The target protein lysozyme but non-target proteins can be trapped by the immobilized anti-lysozyme DNA aptamer. In contrast, lysozyme cannot be trapped by the immobilized oligodeoxynucleotide that does not contain the sequence of the anti-lysozyme DNA aptamer. The study clearly demonstrates the trapping of lysozyme by the immobilized anti-lysozyme DNA aptamer is mainly due to specific recognition rather than simple electrostatic interaction of positively charged protein and the negatively charged DNA. The inter-day precision was determined as 0.8% for migration time and 4.2% for peak area, respectively. By the use of aptamer affinity monolith, a screening strategy is developed to selectively extract lysozyme from chicken egg white, showing the advantages of high efficiency, low cost and ease-of-operation.


Assuntos
Aptâmeros de Nucleotídeos/química , Cromatografia de Afinidade/métodos , Cromatografia Líquida de Alta Pressão/métodos , Muramidase/isolamento & purificação , Animais , Aptâmeros de Nucleotídeos/metabolismo , Galinhas , Metilmetacrilatos , Muramidase/análise , Muramidase/metabolismo , Porosidade , Ligação Proteica , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
9.
ACS Nano ; 5(5): 3937-42, 2011 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-21452888

RESUMO

We report on the preparation of all-silica colloidosomes with adjustable size, shell structure, mechanical strength, and permeability. Our approach is based on the coassembly at the water/oil interface of silica nanoparticles and a silica precursor polymer-hyperbranched polyethoxysiloxane-which acts as a binder for particles as well as an additional interfacial component. Remarkably, the shell of colloidosomes can be fine-tuned from a particle monolayer up to a bilayer bound with a sandwiched thin silica film. This method presents a facile approach toward multiscale production of microcapsules which have a high potential in encapsulation technology and in smart coating formulations.


Assuntos
Coloides/química , Cristalização/métodos , Membranas Artificiais , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Dióxido de Silício/química , Substâncias Macromoleculares/química , Teste de Materiais , Conformação Molecular , Tamanho da Partícula , Propriedades de Superfície
10.
Electrophoresis ; 29(14): 3038-46, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18551715

RESUMO

The measurement of protein binding of highly hydrophobic molecules is challenging due to poor solubility and strong adsorption, and further complicated by the competition of lipophilic partition in biological systems. Here, an attempt is presented to simultaneously simulate protein binding and lipophilic partition of hydrophobic molecules in a single system using CE. In this system, the incorporated biocompatible micelles also facilitate the protein binding study of hydrophobic molecules by enhancing their solubility (27 to 10(4) times) and eliminating the problematic adsorption. An equation is derived to describe the competition of protein binding and lipophilic partition and to estimate the protein binding constants in nonmicellar aqueous solution. Five polycyclic aromatic hydrocarbons (PAHs) and HSA were used as model hydrophobic compounds and protein, respectively. The study of the competition between lipophilic partition and protein binding reveals that the binding of the PAHs to HSA is governed by hydrophobic interactions and such binding (except naphthalene) can be eliminated by the lipophilic partition in the nonionic surfactant Tween-20. The developed method may be extended to evaluate the interactions of various macromolecules (receptors, enzymes, proteins, and DNA/RNA) and hydrophobic molecules.


Assuntos
Eletroforese Capilar/métodos , Micelas , Ligantes , Compostos Policíclicos/isolamento & purificação , Compostos Policíclicos/metabolismo , Polissorbatos , Ligação Proteica , Albumina Sérica/metabolismo
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