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1.
J Chromatogr A ; 1730: 465130, 2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-38955130

RESUMO

This study describes the preparation of a cylindrical polymer foam column termed Chitosan/ß-Cyclodextrin/MIL-68(Al) (CS/ß-CD/MIL-68(Al)). An ice template-freeze drying technique was employed to prepare the CS/ß-CD/MIL-68(Al) foam column by embedding MIL-68(Al) in a polymer matrix comprising cross-linked chitosan (CS) and ß-cyclodextrin (ß-CD). The cylindrical CS/ß-CD/MIL-68(Al) foam was subsequently inserted into a syringe to develop a solid phase extraction (SPE) device. Without the requirement for an external force, the sample solution passed easily through the SPE column thanks to the porous structure of the CS/ß-CD/MIL-68(Al) foam column. Moreover, the CS/ß-CD/MIL-68(Al) foam column was thought to be a superior absorbent for SPE since it included the adsorptive benefits of CS, ß-CD, and MIL-68(Al). The SPE was utilized in conjunction with high-performance liquid chromatography to analyze six sulfonamides found in milk, urine, and water. With matrix effects ranging from 80.49 % to 104.9 % with RSD values of 0.4-14.0 %, the method showed high recoveries ranging from 80.6 to 107.4 % for water samples, 93.4-105.2 % for urine, and 87.4-100.9 % for milk. It also demonstrated good linearity in the range of 10-258 ng·mL-1 with the limits of detection ranging from 1.88 to 2.58 ng·mL-1. The cylindrical CS/ß-CD/MIL-68(Al) foam column prepared in this work offered several advantages, including its simple fabrication, excellent water stability, absence of pollutants, biodegradability, and reusability. It is particularly well-suited for SPE. Furthermore, the developed SPE method, employing CS/ß-CD/MIL-68(Al) foam column, is straightforward and precise, and its benefits, including affordability, ease of preparation, lack of specialized equipment, and solvent economy, underline its broad applicability for the pretreatment of aqueous samples.

2.
Molecules ; 29(12)2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38930797

RESUMO

Pueraria lobata (P. lobata), a traditional anti-diabetic medicine mainly composed of flavonoids and isoflavones, has a long history in diabetes treatment in China. However, the anti-diabetic active component is still unclear. Recently, protein tyrosine phosphatase 1B (PTP1B) has been a hot therapeutic target by negatively regulating insulin signaling pathways. In this study, the spectrum-effect relationship analysis method was first used to identify the active components of P. lobata that inhibit PTP1B. The fingerprints of 12 batches of samples were established using high-performance liquid chromatography (HPLC), and sixty common peaks were identified. Meanwhile, twelve components were identified by a comparison with the standards. The inhibition of PTP1B activity was studied in vitro by using the p-nitrophenol method, and the partial least squares discriminant analysis, grey relational analysis, bivariate correlation analysis, and cluster analysis were used to analyze the bioactive compounds in P. lobata. Peaks 6, 9 (glycitin), 11 (genistin), 12 (4'-methoxypuerarin), 25, 34, 35, 36, 53, and 59 were considered as potentially active substances that inhibit PTP1B. The in vitro PTP1B inhibitory activity was confirmed by glycitin, genistin, and 4'-methoxypuerarin. The IC50s of the three compounds were 10.56 ± 0.42 µg/mL, 16.46 ± 0.29 µg/mL, and 9.336 ± 0.56 µg/mL, respectively, indicating the obvious PTP1B inhibitory activity. In brief, we established an effective method to identify PTP1B enzyme inhibitors in P. lobata, which is helpful in clarifying the material basis of P. lobata on diabetes. Additionally, it is evident that the spectrum-effect relationship method serves as an efficient approach for identifying active compounds, and this study can also serve as a reference for screening bioactive constituents in traditional Chinese medicine.


Assuntos
Inibidores Enzimáticos , Proteína Tirosina Fosfatase não Receptora Tipo 1 , Pueraria , Proteína Tirosina Fosfatase não Receptora Tipo 1/antagonistas & inibidores , Proteína Tirosina Fosfatase não Receptora Tipo 1/metabolismo , Pueraria/química , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/química , Cromatografia Líquida de Alta Pressão , Isoflavonas/farmacologia , Isoflavonas/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Hipoglicemiantes/farmacologia , Hipoglicemiantes/química , Humanos
3.
Molecules ; 28(21)2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37959757

RESUMO

In this study, TpDMB-COPs, a specific class of covalent organic polymers (COPs), was synthesized using Schiff-base chemistry and incorporated into a polyvinylidene fluoride (PVDF) polymer for the first time to prepare COPs mixed matrix membranes (TpDMB-COPs-MMM). A membrane solid-phase extraction (ME) method based on the TpDMB-COPs-MMM was developed to extract trace levels of six sulfonamides from human urine identified by high-performance liquid chromatography (HPLC). The key factors affecting the extraction efficiency were investigated. Under the optimum conditions, the proposed method demonstrated an excellent linear relationship in the range of 3.5-25 ng/mL (r2 ≥ 0.9991), with the low limits of detection (LOD) between 1.25 ng/mL and 2.50 ng/mL and the limit of quantification (LOQ) between 3.50 ng/mL and 7.00 ng/mL. Intra-day and inter-day accuracies were below 5.0%. The method's accuracy was assessed by recovery experiments using human urine spiked at three levels (7-14 ng/mL, 10-15 ng/mL, and 16-20 ng/mL). The recoveries ranged from 87.4 to 112.2% with relative standard deviations (RSD) ≤ 8.7%, confirming the applicability of the proposed method. The developed ME method based on TpDMB-COPs-MMM offered advantages, including simple operation, superior extraction affinity, excellent recycling performance, and easy removal and separation from the solution. The prepared TpDMB-COPs-MMM was demonstrated to be a promising adsorbent for ME in the pre-concentration of trace organic compounds from complex matrices, expanding the application of COPs and providing references for other porous materials in sample pre-treatment.


Assuntos
Polímeros , Sulfonamidas , Humanos , Polímeros/análise , Sulfonamidas/análise , Extração em Fase Sólida/métodos , Cromatografia Líquida de Alta Pressão , Limite de Detecção
4.
ACS Omega ; 8(35): 32017-32026, 2023 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-37692232

RESUMO

A multifunctional cylindrical hybrid foam column, referred to as the chitosan/cyclodextrin/MIL-68(Al) (CS/CD/MIL-68(Al)) foam column, was prepared for the first time. The prepared foam column could be used for the adsorption/removal of hydrophilic and hydrophobic contaminants by different forms. Here, it was placed in hydrophilic dye solutions to investigate the adsorption behavior of methylene blue and trypan blue. The adsorption process followed the pseudo-second-order kinetic model with R2 ranging from 0.9983 to 0.9998 for methylene blue and from 0.9993 to 1.0000 for trypan blue, and the adsorption process was consistent with the Langmuir isothermal model with R2 greater than 0.96. The RL values for methylene blue and trypan blue were 0.8871 and 0.5366, respectively, which were present between 0 and 1, indicating that the adsorption behaviors of the two dyes onto the CS/CD/MIL-68(Al) foam column were favorable. The maximum adsorption capacities (Qm) of methylene blue and trypan blue were 60.61 and 454.55 mg/g at 298 K, respectively. Also, the CS/CD/MIL-68(Al) foam column was spun into a syringe and used to adsorb trace hydrophobic sulfonamides from water in the form of filtration. The porous structure impeded the need for any external force and equipment, allowing the water sample to pass through the foam column smoothly. The conditions of the CS/CD/MIL-68(Al) foam column were optimized. The adsorption was carried out under the condition of pH = 4, the amount of the adsorbent was two foam columns, and no salt was added. It was found that the removal rate of the CS/CD/MIL-68(Al) foam column for six sulfonamides was 100%, and it could be reused at least five times. Therefore, this CS/CD/MIL-68(Al) foam column had a simple preparation method, offered a flexible and diverse form of use, was nonpolluting, biodegradable, and reusable, and could have a wider application in the field of environmental pollutant removal and adsorption.

5.
Biomed Chromatogr ; 36(11): e5454, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35853840

RESUMO

In this work, MIL-53(Al), as an inorganic "filler" component, was embedded in polyvinylidene difluoride (PVDF) and polystyrene-block-polybutadiene (SBS) matrices to prepare two mixed-matrix membranes (MMMs), using a simpler method than that previously reported. The PVDF and SBS membranes retained much of the properties of PVDF, SBS, and native MIL-53(Al). The prepared MMMs were then placed in a vortex-stirred sample solution to develop a membrane solid-phase extraction method to extract estrogens and parabens, which were determined by high-performance liquid chromatography with fluorescence detection. The extraction efficiencies of the two membranes were compared, with the PVDF membrane exhibiting superior performance. In addition, the PVDF membrane was more freestanding and flexible, and its preparation method was also more facile and simple. The extraction conditions were optimized, and the analytical method showed low limits of detection (0.005-0.18 ng/mL), good linearity, and high accuracy, with recoveries ranging from 90.7% to 102.5%. As a result, this membrane solid-phase extraction method indicated its potential for application in aqueous sample pretreatment. For metal-organic framework-based MMM used in this method, in addition to being durable, freestanding, mechanically stable, and possessing a large area, it should also exhibit high metal-organic framework incorporation, good flexibility, and appropriate thickness and weight.


Assuntos
Estruturas Metalorgânicas , Parabenos , Butadienos , Cromatografia Líquida de Alta Pressão/métodos , Elastômeros , Estrogênios , Polímeros de Fluorcarboneto , Estruturas Metalorgânicas/química , Parabenos/análise , Poliestirenos/análise , Polivinil , Extração em Fase Sólida/métodos
6.
J Sep Sci ; 45(4): 845-855, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34931462

RESUMO

Selenium-bridged bis(ß-cyclodextrin)s organic-inorganic hybrid silica material with regular spherical shape as new type of chiral stationary phase was directly synthesized under the one-pot hydrothermal synthesis method, and the chiral stationary phase was further characterized by infrared spectroscopy, scanning electron microscopy, thermogravimetry, and elemental analysis. The results of chiral separation showed that eight chiral compounds including various types of chiral alcohols and flavanone were successfully separated in the reversed-phase separation mode by high performance liquid chromatography, which showed the better chiral resolution effect than that on the C2 position of single ß-cyclodextrin. The mechanism of chiral separation was likely due to multiple interactions such as inclusion, hydrogen bonding, electrostatic interaction, dipole-dipole interaction, and the synergistic effect of two cyclodextrins during the chiral resolution process. The synergy of the two cyclodextrins has great potential for development in chiral resolution.

7.
J Cancer ; 12(10): 3011-3023, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33854601

RESUMO

Background: Cancer-associated fibroblasts (CAFs) are principal constituents of the tumor microenvironment (TME) and play a critical role in tumor progression. The CXCL12/CXCR4 axis regulates multiple facets of the TME. The aim of this study was to determine the relationship between CXCL12 expression in CAFs and the malignant progression of gastric cancer (GC). Methods: In the GEO (Gene Expression Omnibus) database, we performed transcriptome analysis on paired gastric cancer RNA sequencing samples, and scRNA analysis was performed on advanced malignant GC samples from the scRNA sequencing data set. Fibroblast cells were co-cultured with GC cells, and invasion, migration, epithelial-mesenchymal transformation (EMT) were determined. After blocking the expression of fibroblast CXCL12, cells were co-cultured with a GC cell line. Detection of GC cell line invasion, migration, EMT and CXCR4, Wnt5a and ß-Catenin expression levels was performed. Primary CAFs and gastric normal fibroblasts were isolated and CXCL12 mRNA and protein expression were determined. In addition, a cohort of 285 GC cases was established, protein expression was evaluated immunohistochemically, and prognostic results were analyzed. Results: GC transcriptome analysis suggested that cytokine-cytokine receptor interaction and the Wnt signaling pathway in GC tissues were significantly up-regulated. scRNA analysis of advanced malignant GC samples showed that severe intestinal metaplasia (SIM) in GC specimens of different malignant grades had obvious fibroblast clusters compared to non-atrophic gastritis (NAG) and early gastric cancer (EGC). In the SIM group, fibroblast cluster, CXCL12, CXCR4, and Wnt5a were overexpressed. Co-culturing with fibroblast cells significantly increased the invasion, migration, and EMT of GC cells, and blocking CXCL12 in CAFs disturbed the expression of Wnt5a and ß-catenin. In our cohort of GC patients, high CXCL12 expression in CAFs significantly correlated with histological grade (P = 0.012) and TNM stage (P = 0.014), as well as with poor overall survival (p = 0.0107). Conclusion: High expression of CXCL12 in CAFs in a GC microenvironment can affect the migration, invasion, and EMT of GC cells. Furthermore, it can cause poor prognosis in patients with GC.

8.
Cancer Manag Res ; 12: 5147-5158, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32636677

RESUMO

PURPOSE: To investigate the diagnostic efficacy of diffusion kurtosis imaging (DKI) and conventional diffusion-weighted imaging (DWI) for pathological grading. METHODS: From December 2015 to January 2017, consecutive patients suspected of having hepatocellular carcinoma (HCC) without prior treatment were prospectively enrolled in this study. MRI examinations were performed before surgical treatment. HCC patients confirmed by surgical pathology were included in the study. The mean diffusivity (MD) values, mean kurtosis (MK) values, and apparent diffusion coefficient (ADC) were calculated. The differences and correlations of these parameters among different pathological grades were analyzed. The diagnostic efficiency of DKI and DWI for predicting high-grade HCC was evaluated by receiver operating characteristic (ROC) curves. Logistic regression analyses were used to evaluate the predictive factors for pathological grade. RESULTS: A total of 128 patients (79 males and 49 females, age: 56.9±10.9 years, range, 32-80) with primary HCC were included: grade I: 22 (17.2%) patients, grade II: 37 (28.9%) patients, grade III: 43 (33.6%) patients, grade IV: 26 (20.3%) patients. The MK values of stage I, II, III, and IV were 0.86±0.13, 1.06±0.11, 1.27±0.17, and 1.57±0.13, respectively. The MK values were significantly higher in the high-grade group than in the low-grade group and were positively correlated with pathological grade (rho =0.7417, P<0.001). The MK value demonstrated a larger area under the curve (AUC), with a value of 0.93 than the MD value, which had an AUC of 0.815 (P<0.001), and ADC, which had an AUC of 0.662 (P=0.01). The MK value (>1.19), ADC (≤1.29×10-3 mm2/s), and HBV (+) were independent predictors for the pathological grade of HCCs. CONCLUSION: The MK values derived from DKI and the ADC values obtained from traditional DWI were more valuable than the MD values in predicting the histological grade of HCCs and could potentially guide clinical treatment before surgery.

9.
Med Sci Monit ; 26: e922618, 2020 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-32562415

RESUMO

BACKGROUND The multi-arterial CAIPIRINHA-Dixon-TWIST-volume-interpolated breath-hold examination (MA-CDT-VIBE) sequence has the advantage of detecting hypervascular lesions during the arterial phase of magnetic resonance imaging (MRI) of the liver. Liver cirrhosis may be associated with dysplastic nodules. This study aimed to compare the use of routine liver MRI sequences with the MA-CDT-VIBE sequence to identify dysplastic liver nodules in patients with liver cirrhosis. MATERIAL AND METHODS Between February 2016 and March 2017, there were 21 patients with liver cirrhosis who had 33 dysplastic liver nodules, which were detected by comprehensive multisequence MRI as the reference standard for nodule imaging. Liver MRI using edge sharpness assessment by parametric (ESAP) modeling was compared with five dynamic arterial subphases that were included in the MA-CDT-VIBE sequence with a temporal resolution of 2.8 s and an acquisition time of 20 s during one breath-hold. RESULTS In the 21 patients included in the study, the MA-CDT-VIBE technique (30/33 for the first reading and 33/33 for the second reading) showed an improved lesion detection rate compared with the ESAP technique (27/33 for the first reading and 29/33 for the second reading), and for 73% of the patients, MA-CDT-VIBE imaging showed improved arterial parenchyma contrast. There was a high degree of interobserver agreement between the two reads (kappa: 0.68-0.91; P<0.001). CONCLUSIONS The MA-CDT-VIBE sequence of MRI liver imaging improved the detection of dysplastic nodules in cirrhosis of the liver compared with routine liver MRI sequences.


Assuntos
Carcinoma Hepatocelular/diagnóstico por imagem , Cirrose Hepática/diagnóstico por imagem , Neoplasias Hepáticas/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Adulto , Idoso , Artérias , Suspensão da Respiração , Carcinoma Hepatocelular/irrigação sanguínea , Meios de Contraste , Feminino , Humanos , Aumento da Imagem , Processamento de Imagem Assistida por Computador , Hepatopatias/diagnóstico por imagem , Neoplasias Hepáticas/irrigação sanguínea , Masculino , Pessoa de Meia-Idade
10.
Anal Chim Acta ; 1023: 35-43, 2018 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-29754605

RESUMO

A vortex-assisted membrane extraction (VA-ME) method based on several metal-organic framework mixed-matrix membranes (MOF-MMMs) was firstly developed and applied for the analysis of four estrogens in human urine. The MOF-MMMs, with high MOF loading (∼67 wt%), were prepared using a facile approach by embedding the MOFs in a polyvinylidene difluoride matrix. The method was suitable for a wide variety of MOF materials, and the incorporated MOFs retained their unique properties. Being model analytes, the estrogens became adsorbed on the MOFs in the vortex-stirred sample solutions and were subsequently desorbed in methanol and analyzed using high-performance liquid chromatography with fluorescence detection. The performance and durability of MIL-53(Al)-MMM was particularly noteworthy and was therefore selected to extract estrone, 17ß-estradiol, estriol, and ethinylestradiol from the urine of children and postmenopausal women. Various extraction conditions were optimized, and the analytical method showed good linearity in the range of 0.02-200 ng mL-1, recoveries ranging from 80.4% to 102.7% (RSD≤11.4%), and low limits of detection (0.005-1 ng mL-1). VA-ME is a simple, accurate, and cost-effective pretreatment method, and its advantages such as good adsorption performance, simple operation, and straightforward removal and separation from solution highlight its broad utility for aqueous sample pretreatment.


Assuntos
Estrogênios/urina , Extração Líquido-Líquido , Estruturas Metalorgânicas/química , Criança , Cromatografia Líquida de Alta Pressão , Feminino , Voluntários Saudáveis , Humanos , Masculino , Conformação Molecular
11.
Talanta ; 180: 358-367, 2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29332823

RESUMO

In this work, computational and experimental methods were used to study the adsorption of estrogens and glucocorticoids on metal-organic frameworks (MOFs). Computer-aided molecular simulation was applied to predict the adsorption of eight analytes on four MOFs (MIL-101(Cr), MIL-100(Fe), MIL-53(Al), and UiO-66(Zr)) by examining molecular interactions and calculating free binding energies. Subsequently, the four water-stable MOFs were synthesized and evaluated as adsorbents for the target hormones in aqueous solution. As the MOF exhibiting the highest adsorption capacity in both computations and experiments, MIL-53(Al) was chosen as a sorbent to develop a dispersive micro-solid-phase extraction procedure coupled to ultra-performance liquid chromatography tandem mass spectrometry for simultaneous determination of the target analytes in water and human urine samples. Experimental parameters affecting the extraction recoveries, including pH, ionic strength, MIL-53(Al) amount, extraction time, desorption time, and desorption solvent, were optimized. The optimized method provided a linear range of 0.005025-368.6µg/L with good correlation coefficients (0.9982 ≤ r2 ≤ 0.9992), and limits of detection (S/N = 3) and quantification (S/N = 10) of 0.0015-1.0µg/L and 0.005-1.8µg/L, respectively. The analyte recoveries were in the range of 80.6-98.4% in water samples and 88.4-93.2% in urine samples. Furthermore, MIL-53(Al) showed good stability over 10 extraction cycles (RSD < 10.0%). Good agreement between experimental measurements and computational results showed the potential of this approach for elucidating adsorption mechanisms and predicating extraction efficiencies for MOFs and targets, providing new directions for the development and utilization of MOFs.


Assuntos
Estrogênios/análise , Estrogênios/urina , Glucocorticoides/análise , Glucocorticoides/urina , Estruturas Metalorgânicas/química , Microextração em Fase Sólida/métodos , Água/análise , Cromatografia Líquida de Alta Pressão/métodos , Simulação por Computador , Estrogênios/isolamento & purificação , Glucocorticoides/isolamento & purificação , Humanos , Limite de Detecção , Modelos Moleculares , Espectrometria de Massas em Tandem/métodos , Termodinâmica
13.
J Pharm Biomed Anal ; 141: 262-269, 2017 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-28372900

RESUMO

Juglone (JL), as one of the major bioactive components present in the bark of Juglans mandshruica Maxim, exhibits versatile bioactivities, especially anti-cancer activity. To better understand the pharmacokinetic properties of juglone, the protein binding rate of juglone was determined by ultrafiltration method, and the binding affinity and mechanism between JL and human serum albumin (HSA) was investigated in vitro through multi-spectroscopic, thermodynamic, and molecular modeling methods. The binding degree of JL was measured more than 99.0% which suggested that JL had high binding ability to serum albumin. Fluorescence data showed that juglone quench the intrinsic fluorescence of HSA upon forming the JL-HSA nonfluorescent complex at 1:1 stoichiometric proportion, and the complex formation had a high affinity of 104 L·mol-1. Meanwhile, the site marker competitive experiments and the thermodynamic parameters (ΔG=-26.08 kJ·mol-1, ΔH=-16.34 kJ·mol-1, ΔS=32.69 J·mol-1·K-1) indicated that juglone could spontaneously bound to the site I (subdomain IIA) of HAS through hydrophobic and hydrogen bonding interactions. As further revealed by the synchronous fluorescence, three-dimensional fluorescence, Fourier transform infrared (FT-IR) and circular dichroism (CD) spectroscopy, JL could cause conformational and structural alterations of HSA. Additionally, molecular docking was employed to further define the specific binding site and the result was in accordance with the conclusion of experimental analysis. The present work provided reasonable models helping us further understand the pharmacokinetics, pharmacological and toxic effects of JL in vivo and supplied an important insight for the applications of JL in the clinical research.


Assuntos
Naftoquinonas/análise , Sítios de Ligação , Dicroísmo Circular , Humanos , Modelos Moleculares , Simulação de Acoplamento Molecular , Ligação Proteica , Albumina Sérica , Espectrometria de Fluorescência , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica , Ultrafiltração
14.
Zhong Yao Cai ; 35(4): 648-50, 2012 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-23019915

RESUMO

OBJECTIVE: To optimize the extraction technology of total triterpenoids from Hypodematium sinense. METHODS: With 5% vanillin-glacial acetic acid solution and 72% sulfuric acid as chromogenic agent and the content of total tripenoids as index,using single factor experiment and orthogonal test,the optimal extraction condition was determined. RESULTS: The optimal conditions were solid-liquid ratio 1:12, 60% ethanol concentration, and ultrasonic extraction time of 60 min at 60 degrees C. CONCLUSION: The extraction technology is feasible and can be used as extraction process of total triterpenoids from Hypodematium sinense.


Assuntos
Gleiquênias/química , Tecnologia Farmacêutica/métodos , Triterpenos/isolamento & purificação , Ultrassom , Medicamentos de Ervas Chinesas/análise , Medicamentos de Ervas Chinesas/isolamento & purificação , Etanol/química , Componentes Aéreos da Planta/química , Solventes , Temperatura , Fatores de Tempo , Triterpenos/análise
15.
ACS Appl Mater Interfaces ; 4(3): 1186-93, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22304446

RESUMO

Chelating groups are successfully linked to graphene oxide (GO) surfaces through a silanization reaction between N-(trimethoxysilylpropyl) ethylenediamine triacetic acid (EDTA-silane) and hydroxyl groups on GO surface. EDTA-GO was found to be an ideal adsorbent for Pb(II) removal with a higher adsorption capacity. EDTA-modification enhances the adsorption capacity of GO because of the chelating ability of ethylene diamine triacetic acid. This study investigates the adsorption and desorption behaviors of heavy metal cations and the effects of solution conditions such as pH on Pb(II) removal. The adsorption capacity for Pb(II) removal was found to be 479 ± 46) mg/g at pH 6.8, and the adsorption process was completed within 20 min. The Langmuir adsorption model agrees well with the experimental data. The experimental results suggest that EDTA-GO can be reused after washed with HCl, suggesting potential applications in the environmental cleanup.


Assuntos
Ácido Edético/química , Grafite/química , Chumbo/isolamento & purificação , Adsorção , Carvão Vegetal/química , Concentração de Íons de Hidrogênio , Modelos Químicos , Espectrometria por Raios X , Eletricidade Estática , Temperatura , Fatores de Tempo
16.
Zhonghua Fu Chan Ke Za Zhi ; 45(3): 191-6, 2010 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-20450755

RESUMO

OBJECTIVE: To investigate the association between polymorphism of cytochrome P450 subfamily XIA polypeptide 1 (CYP11A1) gene and polycystic ovarian syndrome (PCOS) in Chinese population. METHODS: From May 2005 to Dec. 2008, 290 PCOS cases treated in the First affiliated hospital of Anhui Medical University matched with 344 reproductive women as controls were enrolled in this study. Genotypes of 7 tagging single nucleotide polymorphisms (tSNP, rs12438594, rs4077582, rs9806234, rs16968477, rs4887139, rs1843090, rs11632698) covering CYP11A1 gene (r(2) > or = 0.8) and 3 microsatellite markers (D15S1547, D16S520, D15S1546) were chosed from the phase II database of Han population in HapMap data. Genotype and frequency of allele were detected by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and haplotype of gene polymorphism were analyzed in 290 PCOS cases and 344 controls. RESULTS: Among 7 tSNPs and 3 microsatellite markers, the frequency of rs4077582, D15S1547, D15S1546 and rs11632698 between two groups reached statistical difference (P = 0.010, 0.044, 0.018 and 0.026). The allele frequency of rs4077582, rs4887139, rs1843090, D15S1547 and D16S520 showed significant difference between two groups (P = 0.002, 0.048, 0.030, 0.001 and 0.024). Among 5 haplotype of CYP11A1 (ACGCA13/6/9AG, ACGTA16/6/11AA, GCACG12/8/8AA, GTACA14/4/7GG, GTGCA13/6/7AG), the frequency of GTACA14/4/7GG and ACGCA13/6/9AG were 7.8% (45/580) and 25.3% (147/580) in PCOS group and 11.9% and 19.6% in control group, which showed statistical difference (P < 0.05). There was no significant difference in the level of serum androgen at difference genotype from rs4077582 between two groups (P > 0.05). CONCLUSION: The polymorphism of CYP11A1 gene was associated with PCOS, however, the relationship between gene sequence covered by tSNP/microsatellite markers and hyperandrogenism of PCOS should be further investigated.


Assuntos
Enzima de Clivagem da Cadeia Lateral do Colesterol/genética , Repetições de Microssatélites , Síndrome do Ovário Policístico/genética , Polimorfismo de Nucleotídeo Único , Adulto , Alelos , Estudos de Casos e Controles , China/etnologia , Primers do DNA , Estradiol/sangue , Feminino , Frequência do Gene , Estudos de Associação Genética , Predisposição Genética para Doença , Genótipo , Humanos , Síndrome do Ovário Policístico/etnologia , Reação em Cadeia da Polimerase/métodos , Testosterona/sangue , Adulto Jovem
17.
Reprod Biol Endocrinol ; 7: 141, 2009 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-19948072

RESUMO

BACKGROUND: Polycystic ovary syndrome (PCOS) is a common endocrine disorder associated with an increased risk of type II diabetes mellitus. The results of previous research about the association of the VNTR polymorphism in 5-prime flanking region of the insulin (INS) gene with PCOS have been inconsistent. The present study was to investigate the association of the INS-VNTR polymorphism with PCOS in a Han Chinese population. METHODS: The -23/HphI polymorphism as a surrogate marker of the INS-VNTR length polymorphism was genotyped by polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP) in 216 PCOS patients and 192 non-PCOS women as a control group. Allelic and genotypic frequencies were compared between patients and controls, and these results were analyzed in respect to clinical test data. RESULTS: No significant differences were observed between the cases and controls groups either in allele (P = 0.996) or genotype (P = 0.802) frequencies of INS-VNTR polymorphism; Regarding anthropometric data and hormone levels, there were no significant differences between INS-VNTR genotypes in the PCOS group, as well as in the non-PCOS group. CONCLUSION: The present study demonstrated for the first time that the INS-VNTR polymorphism is not a key risk factor for sporadic PCOS in the Han Chinese women. Further studies are needed to give a global view of this polymorphism in pathogenesis of PCOS in a large-scale sample, family-based association design or well-defined subgroups of PCOS.


Assuntos
Insulina/genética , Repetições Minissatélites/genética , Síndrome do Ovário Policístico/genética , Polimorfismo Genético/fisiologia , Adulto , Alelos , China/epidemiologia , DNA/genética , Etnicidade , Feminino , Genótipo , Hormônios Esteroides Gonadais/sangue , Humanos , Técnicas In Vitro , Pessoa de Meia-Idade , Síndrome do Ovário Policístico/epidemiologia , Polimorfismo Genético/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
18.
J Pharm Biomed Anal ; 48(3): 562-7, 2008 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-18585883

RESUMO

A novel method based on ultra-performance liquid chromatography with photo diode array and electrospray ionization tandem mass spectrometry detection (UPLC-PDA-ESI-MS/MS) was developed for the qualitative and quantitative analysis of flavonoids in the leaves of Isatis indigotica Fort. (Daqingye). The separation was carried out on an Acquity UPLC BEH C(18) column with 0.1% formic acid and methanol as the mobile phase under gradient conditions. Eight flavone C-glucosides were identified and their mass spectrometric fragmentation patterns were studied. Among them, the fragmentation pathways of three flavone 6-C-diglucosides with the rare 1-->3 interglycosidic linkage were investigated for the first time. In addition, a quantitative analytical method for six flavone C-glucosides in Daqingye by UPLC-ESI-MS/MS was established and applied for the determination of commercial Daqingye samples from different resources.


Assuntos
Cromatografia Líquida/métodos , Flavonoides/análise , Isatis/química , Folhas de Planta/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodos , Flavonoides/química , Estrutura Molecular
19.
Artigo em Chinês | MEDLINE | ID: mdl-17094606

RESUMO

Following the requirements of the "National survey on the current status of the major human parasitic diseases", the investigation was conducted in June-October 2002 in 5 districts (counties) of Beijing with a sample of 7912 people. The overall prevalence rate of intestinal parasites was 2.9%, significantly lower than the result from the first survey in 1988-1989 (34.8%) (chi2=3 227.45, P<0.05), revealing that intestinal parasitic infections are not an important risk for people in Beijing Municipality in general.


Assuntos
Enteropatias Parasitárias/epidemiologia , Criança , China/epidemiologia , Humanos , Contagem de Ovos de Parasitas , Prevalência , Inquéritos e Questionários
20.
Zhonghua Liu Xing Bing Xue Za Zhi ; 26(7): 503-6, 2005 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-16335001

RESUMO

OBJECTIVE: To evaluate the safety and immunogenicity of Canada split influenza virus vaccine. METHODS: Cluster samples were by randomly chosen and divided into split vaccination group and homoimported influenza vaccination group. RESULTS: After injection, fever-reaction and local reaction rates of 'trial' group were found as 3.69% and 1.75% respectively, but no statistical significance was found when compared with 'control' group. However the antibody positive rates of 'trail' and 'control' groupsappeared statistically significant (H1N1: 96.8% vs. 92.3%, H3N2: 95.8% vs. 90.2%, B: 52.3% vs. 62.3%). For geometric mean titer (GMT) of type H1N1, H3H2 and B antibody, 'trial' group and 'control' group increased 22.4, 16.8, 8.2 and 21.2, 12.5 and 7.4 times respectively. The antibody protective rates of type H1N1, H3N2 and B were 99%, 99% and 53.9% for 'trial' group, and 96.2%, 98.4% and 62.3% for 'control' but with no statistically significant difference. CONCLUSION: Influenza split vaccine made in Shire company in Canada was safe and with good immunogenicity.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/imunologia , Orthomyxoviridae/imunologia , Vacinas Virais/efeitos adversos , Vacinas Virais/imunologia , Adolescente , Adulto , Fatores Etários , Formação de Anticorpos/imunologia , Canadá , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Injeções , Masculino , Pessoa de Meia-Idade , Fatores de Tempo , Vacinas Virais/administração & dosagem , Adulto Jovem
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