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1.
RSC Adv ; 14(20): 14202-14213, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38690107

RESUMO

In the search for pharmaceutically active compounds from natural products, it is crucial and challenging to develop separation methods that target not only structurally similar compounds but also a class of compounds with desired pharmaceutical functions. To achieve both structure-oriented and function-oriented selectivity, the choice of functional monomers with broad interactions or even biomimetic roles towards targeted compounds is essential. In this work, an imidazole (IM)-functionalized paper membrane was synthesized to realize selectivity. The IM was selected based on its capability to provide multiple interactions, participation in several bioprocesses, and experimental verification of adsorption performance. Using gallic acid as a representative component of Pomegranate Peel, the preparation conditions and extraction parameters were systematically investigated. The optimal membrane solid-phase extraction (MSPE) method allowed for enrichment of gallic acid from the complex matrix of Pomegranate Peel, enabling facile quantitative analysis with a limit of detection (LOD) of 0.1 ng mL-1. Furthermore, with the aid of cheminformatics, the extracted compounds were found to be similar in both their structures and pharmaceutical functions. This work offers a novel approach to preparing a readily synthesized extraction membrane capable of isolating compounds with similar structures and pharmaceutical effects, and provides an MSPE-based analytical method for natural products.

2.
ACS Appl Mater Interfaces ; 15(30): 36822-36830, 2023 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-37467423

RESUMO

Despite the rapid development of versatile metal-organic frameworks (MOFs), the synthesis of water-stable MOFs remains challenging, which significantly limits their practical applications. Herein, a novel engineering strategy was developed to prepare superhydrophobic MOFs by an in situ fluorinated microporous organic network (FMON) coating. Through controllable modification, the resulting MOF@FMON retained the porosity and crystallinity of the pristine MOFs. Owing to the superhydrophobicity of the FMON and the feasibility of MOF synthesis, the FMON coating could be in situ integrated with various water-sensitive MOFs to provide superhydrophobicity. The coating thickness and hydrophobicity of the MOF@FMON composites were easily regulated by changing the FMON monomer concentration. The MOF@FMON composites exhibited excellent oil/water separation and catalytic activities and enhanced durability in aqueous solutions. This study provides a general approach for the synthesis of superhydrophobic MOFs, expanding the application scope of MOFs.

3.
ACS Appl Mater Interfaces ; 14(1): 2102-2112, 2022 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-34968035

RESUMO

Composite adsorbents based on metal-organic frameworks (MOFs) are excellent candidates for solid-phase extraction (SPE) due to their diverse chemical functionality and multilevel porosity. MOF superstructures based on self-assembly at room temperature (RT) could have less energy consumption and easier manipulation due to the larger complex geometry. The π-π stacking of the benzene ring could not only enhance the interaction toward hydrophobic or plane-structured targets but also be expected to promote the formation of the MOF superstructure. In this work, in the established RT self-assembly synthesis system, several factors were investigated to see how to obtain functional MOF superstructures with a regular geometry, among which the number of benzene rings in the ligand was mainly tested for its impact on self-assembly and adsorption capacity. By means of adsorption experiments and computational fluid dynamics (CFD) simulation, the relationship between structure and activity (SARs) was further explored. Interestingly, the MOF unit with the lowest specific surface area performed the best in adsorption. Then, the selected functional MOF superstructure and ionic liquid were used to produce the composite paper membrane facilely applied in the SPE device. After optimization of the preparation conditions and operation parameters, the established SPE-HPLC-UV method could selectively analyze tetracycline-like antibiotics in the range of 16.6-833.3 ng/g (ppb) in a meat sample. This work provided an RT synthesis method to produce a microsize MOF superstructure, with experimental and theoretical insights into the SARs, which could be expanded in the design of other MOF-based SPE composite membranes toward one group of analogues.


Assuntos
Antibacterianos/análise , Líquidos Iônicos/química , Produtos da Carne/análise , Estruturas Metalorgânicas/química , Papel , Extração em Fase Sólida , Adsorção , Materiais Biocompatíveis/química , Teste de Materiais , Estrutura Molecular , Tamanho da Partícula , Propriedades de Superfície , Temperatura
4.
Allergy Asthma Clin Immunol ; 17(1): 39, 2021 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-33865434

RESUMO

BACKGROUNDS: Chronic urticaria is a common disorder of the skin, characterised by recurrent skin wheals and angioedema. Recent reports have shown that altered diversity and composition of the gut microbiota may lead to imbalances in immune regulation, a causal factor in the occurrence of chronic urticaria. OBJECTIVE: This study aimed to evaluate the efficacy of the Yimingjia® probiotic formula in the adjuvant treatment of chronic urticaria in children. METHODS: We enrolled 206 children with confirmed diagnoses of chronic urticaria and randomly assigned them to the treatment (n = 104) or placebo group (n = 102). The children in each group were treated with desloratadine dry suspension, and those in the treatment group also received Yimingjia®. Clinical efficacy was evaluated at 1, 2 and 4 weeks. RESULTS: Clinical symptom scores did not differ significantly at weeks 1 and 2 (p > 0.05), but at 4 weeks, wheal size and attack frequency were significantly reduced in the treatment group (p = 0.049 and 0.03, respectively). The overall response rate (significant improvement + complete response) significantly differed between the treatment (80.8%) and placebo groups (62.5%) (χ2 = 4.20, p = 0.04). CONCLUSION: Adjunct therapy with Yimingjia® was safe and effective at 4 weeks in the treatment of chronic urticaria in children. The study was registered under trial number NCT03328897.

5.
Med Sci Monit ; 22: 3056-61, 2016 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-27571235

RESUMO

BACKGROUND This study aimed to investigate the role of miR-184 in the proliferation and apoptosis of keratinocyte (HaCaT cells). MATERIAL AND METHODS HaCaT cells were cultured in a growth medium. The miR-184 was transfected with siRNA, then cell viability and apoptosis were assayed by MTT and flow cytometry, respectively. The colony-forming efficacy of HaCaT cells were detected as well. mRNA expressions of basic fibroblast growth factor (bFGF) and transforming growth factor (TGF)-ß1 were measured with RT-PCR. The expressions of apoptosis-related proteins caspase-3 and Bcl-x in HaCaT cells were determined by Western blot. RESULTS After miR-184 was transfected with siRNA, cell viability and colony forming ability decreased significantly, and apoptosis was significantly increased. The expressions of growth factors TGF-ß1 and bFGF mRNAs, as well as apoptosis-related proteins Bcl-x, in HaCaT cells declined significantly after miR-184 was transfected with siRNA. In addition, the expression of pro-apoptotic protein caspase-3 increased significantly. CONCLUSIONS Our results suggest distinct roles of miR-184 during the growth, proliferation, and apoptosis of keratinocytes.


Assuntos
Queratinócitos/fisiologia , MicroRNAs/genética , MicroRNAs/metabolismo , Apoptose/fisiologia , Proteínas Reguladoras de Apoptose/metabolismo , Caspase 3/metabolismo , Linhagem Celular , Proliferação de Células/genética , Sobrevivência Celular/genética , Fator 2 de Crescimento de Fibroblastos/genética , Fator 2 de Crescimento de Fibroblastos/metabolismo , Humanos , Queratinócitos/citologia , Queratinócitos/metabolismo , RNA Interferente Pequeno/administração & dosagem , RNA Interferente Pequeno/genética , Transfecção , Fator de Crescimento Transformador beta1/genética , Fator de Crescimento Transformador beta1/metabolismo
6.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 35(8): 975-80, 2015 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-26485914

RESUMO

OBJECTIVE: To observe the effect of Wenyang Huazhuo Tongluo Recipe (WYHZTLR) on the proportion of T helper 17 cells (Thl7)/regulatory T cells (Treg), and serum levels of IL-17 and IL-10 in peripheral blood of systemic sclerosis (SSc) patients with yang qi insufficiency and turbidity induced collaterals blockage syndrome (YQITICBS). METHODS: Totally 82 SSc patients were randomly assigned to the Western medicine group (as the control group) and the integrated Chinese and Western medicine group (as the treatment group), 41 cases in each group. All patients took methotrexate (MTX) tablet and prednisone tablet. Patients in the treatment group additionally took WYHZTLR. The treatment course for all was six consecutive months. Besides, another 70 healthy volunteers were recruited as a healthy control group (as the healthy group). Percentages of Th17 and Treg in peripheral blood were detected by flow cytometry. Serum levels of IL-17, IL-10, von Willebrand factor (vWF), aminoterminal propeptide of type l procollagen (PIIINP), and cross-linked carboxyterminal telopeptide of type I collagen ( I CTP) were measured by double antibody sandwich ELISA. The correlations between Th17/Treg and levels of vWF, PIIINP, I CTP, skin score, and disease activity index were observed by Pearson correlation analysis. RESULTS: The percentage of Th17 in peripheral blood, ratios of Th17/Treg, and the serum level of IL-17 were significantly higher, but the percentage of Treg and the serum level of IL-10 were significantly lower in SSc patients, when compared with those of the healthy group (P <0. 05, P <0. 01). Compared with the same group before treatment, the percentage of Thl7, ratios of Thl7/Treg, and levels of IL-17, vWF, and PIIINP all decreased in the two groups after treatment (P <0.05, P <0.01), but the percentage of Treg and the IL-10 level increased (P <0. 05, P <0. 01). Meanwhile,the level of I CTP was higher in the treatment group after treatment (P <0. 05). The improvement of all indices except the percentage of Th17 was more obvious in the treatment group than in the control group (P <0. 05, P <0. 01). The ratio of Th17/Treg was positively correlated with levels of vWF, PIIINP, skin score, and disease activity index before and after treatment respectively (P <0. 01), but with no obvious correlation with the level of I CTP (P >0. 05). CONCLUSION: WYHZTLR could achieve its therapeutic effect on SSc patients by regulating Th17/Treg imbalance, lowering levels of vWF and PIIINP, and elevating the level of I CTP.


Assuntos
Medicamentos de Ervas Chinesas/uso terapêutico , Escleroderma Sistêmico/tratamento farmacológico , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Humanos , Interleucina-10 , Interleucina-17 , Metotrexato , Fragmentos de Peptídeos , Pró-Colágeno , Linfócitos T Reguladores , Células Th17
7.
Anal Chem ; 87(8): 4442-7, 2015 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-25816054

RESUMO

Lectin array is an important tool in the fields of carbohydrate chemistry, glycobiology, and glycomics. Because natural lectins are associated with some apparent disadvantages such as tedious purification and easy loss of activity, artificial materials are applied to overcome such shortages by mimicking and replacing lectins in an artificial lectin array, among which boronate affinity-based materials are very outstanding and widely used. However, complicated synthetic works are often involved to design and create boronate affinity-based lectin-mimics. In this work, a facile and novel method was proposed to establish a virtual lectin array based on boronate affinity-based pH-featured encoding for discrimination of monosaccharides by pattern recognition. The dependence of boronate affinity on environmental pH was selected to encode each monosaccharide for feature generation, and the pH-featured encoding was used to construct the virtual lectin array. On the basis of the virtual array, pattern recognition algorithms were applied for data analysis. Monosaccharides were discriminated by principal component analysis, and the relations in the virtual lectin array were unraveled by cluster analysis. In this proof-of-concept work, without complicated synthesis or preparation, the proposed method was successful in mimicking lectin array and discriminating nine elementary monosaccharides found in nature, and it was also a new way of encoding in expanding the applications of boronate affinity-based materials and methods in the field of biomimetics.


Assuntos
Ácidos Borônicos/química , Lectinas/química , Monossacarídeos/análise , Algoritmos , Concentração de Íons de Hidrogênio , Análise de Componente Principal
8.
Anal Chem ; 86(24): 12382-9, 2014 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-25405946

RESUMO

Enzyme activity assay is an important method in clinical diagnostics. However, conventional enzyme activity assay suffers from apparent interference from the sample matrix. Herein, we present a new format of enzyme activity assay that can effectively eliminate the effects of the sample matrix. The key is a 96-well microplate modified with molecularly imprinted polymer (MIP) prepared according to a newly proposed method called boronate affinity-based oriented surface imprinting. Alkaline phosphatase (ALP), a glycoprotein enzyme that has been routinely used as an indicator for several diseases in clinical tests, was taken as a representative target enzyme. The prepared MIP exhibited strong affinity toward the template enzyme (with a dissociation constant of 10(-10) M) as well as superb tolerance for interference. Thus, the enzyme molecules in a complicated sample matrix could be specifically captured and cleaned up for enzyme activity assay, which eliminated the interference from the sample matrix. On the other hand, because the boronate affinity MIP could well retain the enzymatic activity of glycoprotein enzymes, the enzyme captured by the MIP was directly used for activity assay. Thus, additional assay time and possible enzyme or activity loss due to an enzyme release step required by other methods were avoided. Assay of ALP in human serum was successfully demonstrated, suggesting a promising prospect of the proposed method in real-world applications.


Assuntos
Ácidos Borônicos/química , Enzimas/química , Glicoproteínas/química , Impressão Molecular
9.
Anal Chem ; 86(1): 959-66, 2014 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-24345219

RESUMO

Molecularly imprinted polymers (MIPs), as inexpensive and stable substitutes of antibodies, have shown great promise in immunoassays. Glycoproteins are of significant diagnostic value. To facilitate the application of MIPs in clinical diagnostics, a general and facile imprinting method toward glycoproteins oriented for an enzyme-linked immunosorbent assay (ELISA) in the form of a 96-well microplate is essential but has not been fully explored yet. In this study, a new method called boronate affinity-based oriented surface imprinting was proposed for facile preparation of glycoprotein-imprinted microplates. A template glycoprotein was first immobilized by a boronic acid-modified microplate through boronate affinity binding, and then, a thin layer of polyaniline was formed to cover the microplate surface via in-water self-copolymerization. After the template was removed by an acidic solution, 3D cavities that can rebind the template were fabricated on the microplate surface. Using horseradish peroxidase (HRP) as a model target, the effects of imprinting conditions as well as the properties and performance of the prepared MIPs were investigated. α-Fetoprotein (AFP)-imprinted microplate was then prepared, and thereby, a MIP-based ELISA method was established. The prepared MIPs exhibited several highly favorable features, including excellent specificity, widely applicable binding pH, superb tolerance for interference, high binding strength, fast equilibrium kinetics, and reusability. The MIP-based ELISA method was finally applied to the analysis of AFP in human serum. The result was in good agreement with that by radioimmunoassay, showing a promising prospect of the proposed method in clinical diagnostics.


Assuntos
Ácidos Bóricos/análise , Glicoproteínas/química , Impressão Molecular/métodos , Ácidos Bóricos/metabolismo , Ensaio de Imunoadsorção Enzimática/métodos , Glicoproteínas/metabolismo , Humanos , Propriedades de Superfície
10.
Electrophoresis ; 33(16): 2591-7, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22899268

RESUMO

Manufacturing materials are an essential element for the fabrication of microfluidic chips. PDMS, the most widely used polymeric material, is associated with apparent disadvantages such as hydrophobic nature, while other materials also suffer from some limitations. In this paper, a new soft lithographic route was proposed for the facile manufacturing of hydrophilic sandwich microchips, using bisphenol A based epoxy acrylate (BABEA) as a new patterning material. The BABEA copolymers are hydrophilic, highly transparent in visible range while highly untransparent when the wavelength is less than 290 nm, and of high replication fidelity. By combining with appropriate monomers, including glycidyl methacrylate, methylmethacrylate, and acrylic acid, the copolymers contain active functional groups, which allows for easy postmodification for desirable functional units. A fabrication procedure was proposed for manufacturing hybrid quartz/BABEA copolymer/quartz microchips. In the procedure, no micromachining equipments, wet etching, or imprinting techniques were involved, making the fabrication approach applicable in ordinary chemistry laboratories. The performance of the prepared microchips was demonstrated in terms of CIEF with UV-whole channel imaging detection. The hydrophilic microchannel ensures stable focusing while the polymeric middle layer acts as a perfectly aligned optical slit for whole channel UV absorbance detection.


Assuntos
Eletroforese Capilar/métodos , Focalização Isoelétrica/métodos , Técnicas Analíticas Microfluídicas/instrumentação , Compostos Benzidrílicos , Resinas Epóxi/química , Interações Hidrofóbicas e Hidrofílicas , Ácidos Polimetacrílicos/química , Espectrofotometria Ultravioleta
11.
Analyst ; 137(17): 4016-22, 2012 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-22785350

RESUMO

Detection is an essential aspect in analytical approaches. In liquid phase separations, many attempts have been focused on the capability to detect a partial or an entire column. However, detection in both spatial and temporal resolutions has not gained much attention yet. Here we present the concept of spatio-temporally resolved detection (STRD) and a proof-of-the-concept microchip electrophoresis (MCE)-STRD system. The MCE-STRD system was mainly composed of a microchip and an STRD unit, which were designed completely based on the requirements for spatial and temporal resolutions. In the STRD unit, a linear light beam expanded from a UV LED light source was employed to illuminate the whole separation channel of the microchip while a linear CCD sensor that has an identical effective length as the separation channel and more pixels per unit length was used to detect the absorbance signals through the separation channel. As each pixel of the CCD sensor can detect a corresponding channel space in real time, the CCD provides both spatial and temporal resolutions. A significant advantage of STRD over conventional detection schemes is its capability for monitoring the dynamic processes of molecular events occurring in the separation channel. This was demonstrated through the monitoring of the dynamic processes of protein-DNA and protein-drug interactions in chip isoelectric focusing (chip IEF). The MCE-STRD system provided not only whole pictures of the entire dynamic processes at-a-glance but also quantitative kinetic information (dissociation rate constants) of the dynamic processes. With further development, we anticipate that STRD could be a promising tool for the characterization of biomolecular interactions and the observation of migration behaviours of analytes.

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