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1.
Environ Sci Pollut Res Int ; 31(16): 24282-24301, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38438641

RESUMO

Exposure to metals increases the risk of many diseases and has become a public health concern. However, few studies have focused on the effect of metal on abdominal aortic calcification (AAC), especially the combined effects of metal mixtures. In this study, we aim to investigate the combined effect of metals on AAC risk and determine the key components in the multiple metals. We tried to investigate the relationship between multiple metal exposure and AAC risk. Fourteen urinary metals were analyzed with five statistical models as follows: generalized linear regression, weighted quantile sum regression (WQS), quantile g-computation (Qgcomp), and Bayesian kernel machine regression (BKMR) models. A total of 838 participants were involved, of whom 241 (28.8%) had AAC. After adjusting for covariates, in multiple metal exposure logistic regression, cadmium (Cd) (OR = 1.364, 95% CI = 1.035-1.797) was positively associated with AAC risk, while cobalt (Co) (OR = 0.631, 95% CI = 0.438-0.908) was negatively associated with AAC risk. A significant positive effect between multiple metal exposure and AAC risk was observed in WQS (OR = 2.090; 95% CI = 1.280-3.420, P < 0.01), Qgcomp (OR = 1.522, 95% CI = 1.012-2.290, P < 0.05), and BKMR models. It was found that the positive association may be driven primarily by Cd, lead (Pb), uranium (U), and tungsten (W). Subgroups analysis showed the association was more significant in participants with BMI ≥ 25 kg/m2, abdominal obesity, drinking, and smoking. Our study shows that exposure to multiple metals increases the risk of AAC in adults aged ≥ 40 years in the USA and that Cd, Pb, U, and W are the main contributors. The association is stronger in participants who are obese, smoker, or drinker.


Assuntos
Cádmio , Metais Pesados , Adulto , Humanos , Teorema de Bayes , Chumbo , Inquéritos Nutricionais , Cobalto , Obesidade
2.
Huan Jing Ke Xue ; 44(12): 6653-6663, 2023 Dec 08.
Artigo em Chinês | MEDLINE | ID: mdl-38098392

RESUMO

Cities are the center of energy consumption. Electrification integrates urban energy structure and achieves the efficient use of clean energy. Exploring the urban impact of accelerated electrification under the low-carbon path is crucial to reducing urban pollution and carbon. Based on the Long-range Energy Alternative Planning System(LEAP-DG), this study set up three scenarios, including the baseline, low-carbon, and accelerated electrification scenarios, to evaluate the emission reduction potential of electrification under different power structures, quantify the contribution of key sectors, and discuss the coordinated emission reduction effect of Dongguan, a typical manufacturing city in Guangdong. The results showed that accelerated electrification under the low-carbon path would reduce the emission intensity of power pollutants, and in 2050, Dongguan will further reduce CO2, NOx, VOC, and CO by 7.35×106, 1.28×104, 1.62×104, and 8.13×104 t; SO2 and PM2.5 emission reductions on the consumption side and increased emissions on the production side had been balanced. Accelerated electrification in the industrial and transportation sectors would reduce CO2 and air pollutant emissions at the same time, and the transportation sector would benefit from the high conversion efficiency of fuel vehicles and electric vehicles, reducing CO2, CO, VOC, and NOx by 5.42×106, 7.76×104, 1.43×104, and 1.06×104 t, respectively, in 2050. In the building sector with high electrification rates, coal power was higher in extra electricity, increasing CO2 and pollutant emissions. Under the optimization of power supply structure, cities can reasonably adjust the electrification of different departments to achieve targeted pollution prevention and control.

3.
Huan Jing Ke Xue ; 44(8): 4262-4270, 2023 Aug 08.
Artigo em Chinês | MEDLINE | ID: mdl-37694621

RESUMO

Quantifying the contribution of transport processes to air pollution events has been a prominent challenge and an important need in regional air pollution prevention and control. The WRF-Chem model was used to simulate a typical regional ozone (O3) pollution event in Foshan, and the four-dimensional flux method was applied to quantify the transport fluxes of ozone and its precursors from the surrounding areas to Foshan and to clarify the contributions of the direct transport of ozone and transport of precursors. The average ozone flux from the surrounding areas to Foshan was 120.3 t·h-1, the volatile organic compound (VOCs) flux was 30.2 t·h-1, and the corresponding ozone formation potential (OFP) was 114.8 t·h-1. By counting the transport fluxes of each ozone pollution event, it was found that the city with the largest ozone flux into Foshan during the pollution period was Guangzhou (contributed 44%); the city with the largest input VOCs flux was Zhaoqing (contributed 48%). The analysis of ozone generation potential due to transported VOCs emissions found that oxygenated volatile organic compounds (OVOCs) contributed the most to OFP, accounting for 47% of the "maximum input events." OVOCs and aromatic hydrocarbons such as formaldehyde, xylenes, aldehydes, acetone, and phenols were the top five species contributing to the OFP, contributing more than 50% of the total OFP, mainly from industrial solvent sources.

4.
Front Psychol ; 14: 1135808, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37089730

RESUMO

Recently, hip-hop pedagogy or Hip-Hop Based Education (HHBE) have become buzz words in the academic and public debate around hip-hop. However, we found that most definitions of hip-hop pedagogy are missing the concept of pedagogy itself. One consequence of failing to adequately explain the concept of pedagogy is that it may lead future hip-hop researchers, students, and teachers inadvertently to disseminate misinformation or foster unclear thinking by using "hip-hop pedagogy" in inaccurate or vague ways. For these reasons, it is important to have a shared understanding of hip-hop pedagogy. In this article, we present three updated, expanded definitions of hip-hop pedagogy with the potential for widespread acceptance. These definitions aim to convey in the simplest terms what hip-hop pedagogy is for the purpose of informing educators and preparing them to use data.

5.
Front Psychol ; 13: 952124, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35865684

RESUMO

This article reports on the evolution of breakdance. Given the inclusion of breakdancing in the 2024 Olympic Games in Paris, France, scholars have generated substantial international research related to breakdance teaching in recent years. However, few researchers have focused on the impact of formal formative assessment on breakdance teachers' teaching and students' learning. We wish to contribute to the quality of breakdance teaching and learning by identifying the positive impact of recent research on formative assessment on student learning and designing a formal formative assessment task related to breakdance. This article lays out a framework of formal formative assessment tasks and identifies the positive impact of formative assessment on dance education. Although our work is far from perfect, it does provide a general methodological framework for assessing breakdance students' abilities in formal educational settings.

6.
Huan Jing Ke Xue ; 41(8): 3621-3628, 2020 Aug 08.
Artigo em Chinês | MEDLINE | ID: mdl-33124335

RESUMO

In order to explore the spatial and temporal characteristics of the phytoplankton community structure and its influencing factors in Shanghai rivers, the water quality and phytoplankton community structure at 44 river channel sites in a central urban area, new town area, and rural area in Shanghai were investigated from September to October 2018 (autumn) and July to August 2019 (summer). The results showed that:① Chlorophyta was the dominant phyla during the autumn and summer, and was followed by Cyanobacteria and Bacillariophyta. Cyanobacteria dominated the phytoplankton community in terms of density. The number of species and density of phytoplankton were 24% and 2.77 times higher, respectively, than those during the summer and autumn. The dominance of Microcystis sp. was obvious during the autumn (Y=0.16), but there was no absolute dominant species during the summer. ② The difference in the number of phytoplankton species among the three regions was not significant, and the density of the total phytoplankton and cyanobacteria species showed a similar spatial pattern:rural area > new town area > central urban area. Additionally, no significant difference was observed in the total phytoplankton and Cyanobacteria density among the three regions during the autumn (P>0.05), whereas it was 1.82 and 1.93 times higher, respectively, in the rural area in comparison to the central urban area during the summer (P<0.05). Montecarlo test results revealed that the main factors affecting the phytoplankton community structure during the autumn were secchi disk transparency (SD), total phosphorus (TP), total nitrogen (TN), and turbidimetry (Turb), whereas these were TN, Turb, SD, and pH during the summer. ③ The results of a redundancy analysis (RDA) indicated that during the autumn, the phytoplankton in the rivers of the new town area were mainly affected by Turb, TN, and TP, while the rural rivers were mainly affected by SD. During the summer, the phytoplankton in the rivers of the new town and rural areas were mainly affected by TN and Turb. The influencing factors in the central urban area were complex.


Assuntos
Diatomáceas , Fitoplâncton , China , Monitoramento Ambiental , Nitrogênio/análise , Fósforo/análise , Rios , Estações do Ano
7.
Environ Sci Pollut Res Int ; 27(29): 36913-36919, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32577963

RESUMO

Manure-based fertilizer is usually applied to agricultural soils to increase soil fertility and improve soil quality. However, this practice has an impact on the soil environment, e.g., increasing heavy metal contents. The aim of this study was to evaluate and estimate the accumulation tendencies of eight heavy metals, including arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), mercury (Hg), lead (Pb), manganese (Mn), and zinc (Zn) in a soil fertilized continuously with dairy manure through a 5 years' field-scale experiment. Contents of the As, Cd, Cr, Cu, Mn, and Zn gradually increased with the fertilization time of dairy manure at the stable rate of around 326 t hm-2 year-1, leading to annual mean increases of 3.6%, 2.4%, 3.9%, 3.8%, 4.2%, and 6.1%, respectively. Based on the prediction of a dynamic mass balance model using the current practice, the contents of Cd and Zn in the fertilized soil would reach the Chinese standard values for agricultural soils in 48 and 35 years. The mitigation measures, such as lower application rates, for the environmental risk of heavy metal accumulation should be considered.


Assuntos
Metais Pesados/análise , Poluentes do Solo/análise , China , Monitoramento Ambiental , Fertilizantes , Esterco/análise , Solo
8.
J Phys Condens Matter ; 32(41): 415603, 2020 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-32503012

RESUMO

In this paper, we study theoretically the doping evolution behaviors of the magnetic excitations (MEs) in the monolayer CuO2 grown on Bi2Sr2CaCu2O8+δ substrate. For the undoped system, the MEs exhibit the low energy commensurate behavior around (π, π). They turn to be incommensurate when the system is slightly hole-doped. In the intermediate doping regime, the low energy MEs diminish gradually. They turn to be dominated by the high energy modes. With further doping, an exotic structure transition of the MEs occurs in the heavily hole-doped regime which is directly related to the Lifshitz transition. Distinct MEs are separated by the transition point around which the low energy MEs exhibit the ring-like structure around (0, 0). Before the transition, the MEs are dominated by the broad particle-hole continuum at very high energies. In contrast, across the transition point, two new low energy modes develop around (0, 0) and (π, π) attributing to the intrapocket and interpocket particle-hole scatterings, respectively.

9.
Huan Jing Ke Xue ; 40(10): 4647-4653, 2019 Oct 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854834

RESUMO

Pot-culture experiments were carried out in Shanghai to screen crop varieties with low bioaccumulation properties with respect to cadmium (Cd). Eight common crops, such as green pepper, cucumber, cowpea, spinach, cauliflower, tomatoes, rice, and wheat, were planted in contaminated soil with different Cd concentrations of 0.23, 0.6, 1.2, 1.8, 2.4, and 3.0 mg·kg-1 to investigate the effects on biomass, Cd accumulation characteristics, and edible risk safety. The results indicated that:① With the increase in soil Cd content, the aboveground biomass of crops increased firstly and then decreased. The different crop types had different tolerance to Cd, with green pepper showed the strongest tolerance and spinach and tomato showed the least tolerance. ② The bioaccumulation factor of Cd in the edible parts of eight crops ranged in order of wheat > spinach > rice > green pepper > cauliflower > tomato > cucumber > cowpea. ③ Total Cd content in soil was significantly correlated with Cd content in the crops (P<0.05), and the order of the correlation coefficients was spinach > wheat > tomato > cucumber > green pepper > rice > cauliflower > cowpea. ④ The risk threshold value of Cd in soil based on the edible safety of different crops ranged in order of cowpea > cucumber > cauliflower > green pepper > tomato > rice > spinach > wheat. Cucumber, cowpea, and cauliflower were selected as the low-Cd-accumulating varieties according to their tolerance to soil Cd, bioaccumulation capacity, and edible risk threshold values.

10.
J Mater Chem B ; 3(37): 7377-7385, 2015 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-32262764

RESUMO

Tetrapod gold nanocrystals, to be the core of surface-enhanced Raman spectroscopy (SERS) nanoprobes, with tunable localized surface plasmon resonance (LSPR) from 650 nm to 785 nm in the Vis-NIR region have been successfully prepared by a facile seeded growth approach. The local electromagnetic field distribution and the huge extinction cross section of the tetrapod gold nanocrystals were simulated by a finite-difference time-domain method. Both the calculated and experimental results reveal that the LSPR property of the tetrapod gold nanocrystals is closely dependent on the morphology features of their tips, where a strong field enhancement appears. These tetrapod nanocrystals have exhibited a good capability not only for Raman signal enhancement but also when successfully utilized as NIR SERS bioimaging nanoprobes. In vitro SERS imaging of stained breast cancer cells has also been demonstrated. The tetrapod gold nanocrystals developed here with a precisely tunable LSPR offer advantages of enhanced signal quality, good stability and better biocompatibility in SERS imaging, which has great potential for various biomedical applications.

11.
Scand J Clin Lab Invest ; 74(8): 693-9, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25223598

RESUMO

OBJECTIVE: To develop a gold nanoparticle-based visual DNA microarray for simple and rapid screening of EGFR gene mutations. METHODS: The DNA fragments contain epidermal growth factor receptor (EGFR) exons 18, 19, 20 and 21 were amplified by polymerase chain reaction (PCR) using biotin-modified primers. The amino-modified oligonucleotides were immobilized on glass surface, which were used as the capturing probes to bind the complement biotinylated target DNA. After the PCR product has been hybridized to the immobilized capture probe DNA on the glass slides, the Streptavidin-conjugated gold nanoparticles were introduced to the microarray via specific binding to 5'-end biotin of the PCR products. The hybridization signal on array spots was enhanced and visualized by silver amplification. The EGFR mutation in 286 clinical samples from cancer patients were tested using the gold nanoparticle-based microarray and verified with Sanger DNA sequencing method. RESULTS: A novel visual DNA microarray has been developed to detect EGFR mutations in tumor tissue specimens rapidly; its limit of detection (LOD) is up to 10(-9) mol/L and distinguishes power to detect 5% gene mutation in the mixture samples. CONCLUSION: For its high specificity and sensitivity, simplicity, lower price and higher speed, the present visual mutation detecting technique has potential application in clinical fields.


Assuntos
Análise Mutacional de DNA/métodos , Receptores ErbB/genética , Sequência de Bases , Carcinoma Pulmonar de Células não Pequenas/genética , Análise Mutacional de DNA/normas , Ouro/química , Humanos , Limite de Detecção , Neoplasias Pulmonares/genética , Nanopartículas Metálicas/química , Mutação , Análise de Sequência com Séries de Oligonucleotídeos
12.
Contrast Media Mol Imaging ; 9(5): 349-54, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24729581

RESUMO

A new method for imaging the tumor human vascular endothelial growth factor 165 (VEGF 165) is presented. A magnetic resonance imaging (MRI) probe was prepared by crosslinking ultrasmall superparamagnetic iron oxide (USPIO) nanoparticles to the aptamer for tumor vascular endothelial growth factor 165 (VEGF165-aptamer). The molecular probe was evaluated for its in vitro and in vivo activities toward VEGF165. Enzyme-linked immunosorbent assay showed that the VEGF165-aptamer-USPIO nanoparticles conjugate specifically binds to VEGF165 in vitro. A cell proliferation test showed that VEGF165-aptamer-USPIO seems to block the proliferation of human umbilical vein endothelial cells induced by free VEGF165, suggesting that VEGF165 is an effective target of this molecular probe. In xenograft mice carrying liver cancer that expresses VEGF165, T2-weighted imaging of the tumor displayed marked negative enhancement 3 h after the intravenous administration of VEGF165-aptamer-USPIO. The enhancement disappeared 6 h after administration of the probe. These results suggest the targeted imaging effect of VEGF165-aptamer-USPIO probe in vivo for VEGF165-expressing tumors. This is the first report of a targeted MRI molecular probe based on USPIO and VEGF165-aptamer.


Assuntos
Meios de Contraste , Imageamento por Ressonância Magnética , Sondas Moleculares/química , Fator A de Crescimento do Endotélio Vascular/isolamento & purificação , Animais , Aptâmeros de Nucleotídeos , Aptâmeros de Peptídeos/química , Linhagem Celular Tumoral , Meios de Contraste/química , Dextranos/química , Células Endoteliais da Veia Umbilical Humana , Humanos , Nanopartículas de Magnetita/química , Camundongos
13.
Huan Jing Ke Xue ; 33(7): 2419-26, 2012 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-23002621

RESUMO

The physicochemical properties of water-washed fly ash (FA) and acid modified fly ash (M-FA) were investigated. The adsorption of methylene blue by FA and M-FA were studied by batch experiments. Two methods, Fenton-drive oxidation regeneration and thermal regeneration, were used for regeneration of the used FA and M-FA. The result showed that the rate of adsorption process followed the second order kinetics and the adsorption followed Langmuir isotherms. The adsorption equilibrium time was 30 min, and the equilibrium adsorption capacity of FA and M-FA were 4.22 mg x g(-1) and 5.98 mg x g(-1) respectively. The adsorption capability of M-FA was higher than that of FA. In the range of pH 2-12, the adsorption capacity of M-FA increased with the increase of pH, whereas the adsorption capacity of FA decreased slowly until the pH 8 and then increased. Electrostatic adsorption was the major factor on the adsorption capacity. Around 61% and 55% percentage regeneration (PR) were obtained for FA and M-FA respectively when 78.4 mmol x L(-1) H2O2 and 0.72 mmol x L(-1) Fe2+ were used. When the condition of thermal regeneration was 400 degrees C and 2 h, a positive correlation can be found between the PRs of FA and regeneration times, the PRs were 102%, 104% and 107% in three cycles of adsorption-thermal regeneration process. However a negative correlation can be found between the PRs of M-FA and regeneration times, the PRs were 82%, 75% and 74% in three cycles of adsorption-thermal regeneration process. The PR of FA was higher than that of M-FA, and thermal regeneration was superior to Fenton-drive regeneration.


Assuntos
Cinza de Carvão/química , Azul de Metileno/isolamento & purificação , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química , Adsorção , Peróxido de Hidrogênio , Ferro , Azul de Metileno/química , Oxirredução , Centrais Elétricas , Termodinâmica
14.
Prostate ; 66(8): 858-66, 2006 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-16491483

RESUMO

BACKGROUND: Raising selectivity to tumor cells is a major challenge for most chemotherapy drugs. One of approaches to realizing this goal is antibody-directed enzyme prodrug therapy (ADEPT). This study was done to investigate the curative effect of a new ADEPT system for the treatment of prostate cancer. METHODS: Methotrexate (MTX) prodrugs were synthesized and anti-seminoprotein (SM) single-chain antibody/human carboxypeptidase-A fusion protein (scFv/hCPA) was prepared. Therapeutic effects of this ADEPT system were evaluated. RESULTS: The synthesis of prodrugs was successful and the prodrugs were confirmed no cytotoxicity, but hydrolysis with tumor-targeted scFv/hCPA fusion protein gave 1,000-fold higher cytotoxicity than MTX-alpha-Phe only. Cell cycle assays showed that tumor cells were arrested in the S phase after ADEPT treatment; furthermore, tumors were inhibited significantly in scFv/hCPA and MTX-alpha-Phe treated mice. CONCLUSIONS: Our results suggest that targeted activation cytotoxicity against established prostate cancer by scFv/hCPA mediated ADEPT is tumor-specific and has no systemic toxicity in vitro and in vivo.


Assuntos
Carboxipeptidases A/uso terapêutico , Sistemas de Liberação de Medicamentos , Metotrexato/análogos & derivados , Fenilalanina/análogos & derivados , Pró-Fármacos/uso terapêutico , Neoplasias da Próstata/tratamento farmacológico , Proteínas Recombinantes de Fusão/uso terapêutico , Animais , Anticorpos Antineoplásicos/administração & dosagem , Anticorpos Antineoplásicos/farmacologia , Anticorpos Antineoplásicos/uso terapêutico , Carboxipeptidases A/administração & dosagem , Carboxipeptidases A/imunologia , Carboxipeptidases A/farmacologia , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Região Variável de Imunoglobulina/administração & dosagem , Região Variável de Imunoglobulina/farmacologia , Região Variável de Imunoglobulina/uso terapêutico , Masculino , Metotrexato/administração & dosagem , Metotrexato/imunologia , Metotrexato/farmacologia , Metotrexato/uso terapêutico , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Transplante de Neoplasias , Células-Tronco Neoplásicas , Fenilalanina/administração & dosagem , Fenilalanina/imunologia , Fenilalanina/farmacologia , Fenilalanina/uso terapêutico , Pró-Fármacos/administração & dosagem , Pró-Fármacos/farmacologia , Antígeno Prostático Específico/imunologia , Neoplasias da Próstata/imunologia , Neoplasias da Próstata/patologia , Proteínas Recombinantes de Fusão/administração & dosagem , Proteínas Recombinantes de Fusão/farmacologia , Transplante Heterólogo
15.
Sheng Li Xue Bao ; 57(5): 643-7, 2005 Oct 25.
Artigo em Chinês | MEDLINE | ID: mdl-16220204

RESUMO

To identify up-regulated genes in adult rat cardiac fibroblasts (CF) induced by angiotensin II (Ang II), suppression subtractive hybridization (SSH) was performed between the CF stimulated by Ang II (tester) and unstimulated CF (driver) to generate subtractive cDNA library. The library was screened with dot blots hybridization to further verify the differentially expressed cDNA clones. Partial positive clones (19 up-regulated genes) were sequenced and BLAST analyzed. Twelve up-regulated genes related to extracellular matrix, cell cycle, intracellular signal transduction, cell cytoskeleton, cell metabolism and 7 new expressed sequence tags (EST) were acquired (GenBank accession number: CN382808, CN382809, CN382810, CN382811, CN382812, CN382813, CN382814). Our data reveal that SSH is a powerful technique of high sensitivity for the detection and cloning of up-regulated genes expressed in CF induced by Ang II, which may be helpful to clarify the mechanism of cardiac remodeling.


Assuntos
Angiotensina II/farmacologia , Fibroblastos/citologia , Regulação da Expressão Gênica , Miocárdio/citologia , Animais , Células Cultivadas , DNA Complementar/genética , Etiquetas de Sequências Expressas , Masculino , Ratos , Ratos Sprague-Dawley , Regulação para Cima , Remodelação Ventricular/genética
16.
Zhonghua Jie He He Hu Xi Za Zhi ; 28(5): 297-300, 2005 May.
Artigo em Chinês | MEDLINE | ID: mdl-15949307

RESUMO

OBJECTIVE: To develop a pyrosequencing approach to rapid detection of rifampin resistance in Mycobacterium tuberculosis based on characterization of all possible mutations in the 81 bp core region. METHODS: Two pyrosequencing sequencing primers and 1 pair of PCR primers were chosen for pyrosequencing analysis. The sensitivity of the pyrosequencing approach was determined by assaying PCR products generated from 10-fold serial dilutions of the DNA from Mycobacterium tuberculosis H(37) Rv strains. The efficacy of the pyrosequencing approach was evaluated by analyzing clinical Mycobacterium tuberculosis isolates with known antibiotic phenotypes. RESULTS: Rifampin resistance could be determined within 2 hours after PCR amplification and single-stranded template preparation by using only two pyrosequencing reactions. About 50 fg DNA/reaction was required in order to get sufficient PCR product for producing a long, clear and accurate pyrosequencing pattern. A total of 41 Mycobacterium tuberculosis isolates were tested and the results were concordant with those based on drug susceptibility testing and conventional DNA sequencing. CONCLUSION: The pyrosequencing technique is simple to perform and can be used as a rapid, high-throughput and efficient method for detecting rifampin resistance in Mycobacterium tuberculosis.


Assuntos
Antituberculosos/farmacologia , Farmacorresistência Bacteriana , Mycobacterium tuberculosis/efeitos dos fármacos , Rifampina/farmacologia , Análise de Sequência de DNA/métodos , DNA Bacteriano/genética , Testes de Sensibilidade Microbiana , Mutação , Mycobacterium tuberculosis/genética , Reação em Cadeia da Polimerase/métodos
17.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 21(3): 371-4, 2005 May.
Artigo em Chinês | MEDLINE | ID: mdl-15862161

RESUMO

AIM: To develop a new method for antibody detection based on fluorescence polarization (FP) technique. METHODS: BALB/c mice were immunized with single epitope synthetic 8 branches peptide antigen (SVEVGKVADL)8 of Helicobacter pylori (Hp) UreB protein. FP values of the corresponding linear peptide antigen labeled with FITC in different concentration were measured to determine the optimal concentration of the antigen. The antigenicity of the synthetic linear peptide was identified by FP assay. Then, the antibody-positive and negative murine sera were used in FP assay to determine the optimal dilution factor of serum samples. To apply FP technique in Hp antibody detection, 126 human serum samples were detected either by FPIA (fluorescence polarized immunoassay) using the single epitope linear synthetic peptide as antigen or by a commercial ELISA kit. Then, receiver operating characteristic (ROC) curve analysis was performed on the FPIA results by MedCalc software. RESULTS: The UreB single epitope peptide had strong antigenicity. 1.0 nmol/L of the synthetic linear peptide labeled with FITC was the optimal concentration of the antigen and the optimal dilution factor of serum sample was 1:25. In 77 Hp antibody-positive serum samples detected by ELISA, 66 samples were positive by FP detection method. The sensitivity and specificity of the FPIA assay was 85.7% and 98%, respectively. CONCLUSION: The single epitope synthetic peptide antigen can be used in FP method for rapid detection of serum antibody against Hp UreB. The established FP assay for antibody detection may be used in clinical diagnosis in the future.


Assuntos
Anticorpos Antibacterianos/análise , Antígenos de Bactérias/imunologia , Proteínas de Bactérias/imunologia , Epitopos/imunologia , Imunoensaio de Fluorescência por Polarização/métodos , Helicobacter pylori , Peptídeos/síntese química , Animais , Anticorpos Antibacterianos/imunologia , Antígenos de Bactérias/metabolismo , Ensaio de Imunoadsorção Enzimática , Epitopos/metabolismo , Fluoresceína-5-Isotiocianato/metabolismo , Modelos Lineares , Camundongos , Peptídeos/imunologia , Peptídeos/metabolismo
18.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 22(1): 61-4, 2005 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-15696482

RESUMO

OBJECTIVE: To develop a new method that can determine the apolipoprotein E(apoE) genotypes rapidly in high throughput. METHODS: Genome DNA samples were extracted from the anticoagulated peripheral blood samples of 79 patients with Alzheimer's disease(AD) and 63 healthy individuals, and the 492 bp apoE gene fragments including 112 and 158 codons were amplified by polymerase chain reaction (PCR). With one PCR product, three recombined alleles (epsilon 2, epsilon 3 and epsilon 4) of apoE gene as controls were obtained by cloning and site-directed mutagenesis. The excess primers and dNTPs in all PCR products were removed by treatment with clean up reagents, then template-directed dye-terminator incorporation reaction (TDI) was performed and R110 or TAMRA labeled Acyclo-terminators were added into the mutation sites specifically. Fluorescence polarization value (FP) was measured using victor 2 multilabel counter and the polymorphisms in 112 and 158 condons of apoE gene were investigated. RESULTS: The apoE genotypes in recombined plasmid controls and all serum samples were analyzed using the authors' TDI-FP method, and the reliability and specificity were confirmed by DNA sequencing. The frequency of epsilon 4 allele in patients was significantly higher than that in controls, suggesting that apoE epsilon 4 allele gene is a risk factor for late-onset AD. CONCLUSION: TDI-FP is an easy, reliable and high throughput technology in analyzing polymorphism of apoE gene; it can be used in the prediction of susceptibility to AD in elderly individuals. Furthermore, it is an ideal method for large-scale screening and for studying the relationship between the allelic and genotypic frequencies of apoE and other diseases.


Assuntos
Apolipoproteínas E/genética , Reação em Cadeia da Polimerase/métodos , Idoso , Alelos , Doença de Alzheimer/genética , Frequência do Gene , Genótipo , Humanos , Pessoa de Meia-Idade , Polimorfismo Genético , Reprodutibilidade dos Testes
19.
Diagn Microbiol Infect Dis ; 51(2): 135-7, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15698720

RESUMO

Rifampin resistance in Mycobacterium tuberculosis could be determined within 2 h by using pyrosequencing-based approach. Pyrosequencing results of rifampin-resistant (n = 21) and rifampin-susceptible (n = 20) M. tuberculosis isolates were concordant with those based on drug susceptibility testing and conventional DNA sequencing. Results showed pyrosequencing-based approach is a rapid, sensitive, and efficient detection method of rifampin-resistant M. tuberculosis.


Assuntos
Antibióticos Antituberculose/farmacologia , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/isolamento & purificação , Reação em Cadeia da Polimerase/métodos , Rifampina/farmacologia , Sequência de Bases , DNA Bacteriano/análise , Farmacorresistência Bacteriana , Feminino , Humanos , Indicadores e Reagentes , Masculino , Testes de Sensibilidade Microbiana , Dados de Sequência Molecular , Técnicas de Amplificação de Ácido Nucleico , Estudos de Amostragem , Sensibilidade e Especificidade
20.
World J Gastroenterol ; 11(4): 508-10, 2005 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-15641135

RESUMO

AIM: To develop a real-time PCR for detecting hepatitis B virus (HBV) DNA based on TaqMan technology using a new MGB probe. METHODS: Plasmid containing the sequence of X gene (1414-1744 nt) was constructed as HBV-DNA standard for quantitative analysis. A TaqMan-MGB probe between primers for amplification was designed to detect PCR products. The interested sequence contained in the plasmid and in clinical specimens was quantitatively measured. RESULTS: The detection limit of the assay for HBV DNA was 1 genome equivalent per reaction. A linear standard curve was obtained between 10(0) and 10(9) DNA copies/reaction (r>0.990). None of the negative control samples showed false-positive reactions in duplicate. HBV DNA was detected in 100% (50/50) of HBV patients with HbeAg, and in 72.0% (36/50) with HBsAg, HBeAb and HBcAb. The coefficient of variation for both intra- and inter-experimental variability demonstrated high reproducibility and accuracy. CONCLUSION: Real-time PCR based on TaqMan-MGB probe technology is an excellent method for detection of HBV DNA.


Assuntos
Vírus da Hepatite B/genética , Vírus da Hepatite B/isolamento & purificação , Hepatite B Crônica/diagnóstico , Reação em Cadeia da Polimerase/métodos , Taq Polimerase , Sequência de Bases , Sondas de DNA/genética , DNA Viral/análise , Humanos , Dados de Sequência Molecular , Plasmídeos , Reação em Cadeia da Polimerase/normas , Proteínas Recombinantes/genética , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
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