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1.
Vet Microbiol ; 240: 108511, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31902508

RESUMO

Since late 2010, highly virulent PEDV G2-genotype strains have emerged globally extracting heavy losses on the pork industries of numerous countries. We investigated the characteristics of a field strain of PEDV (PEDV strain SH) isolated from a piglet with severe diarrhea on a farm in Shanghai China. Whole genome sequencing and analysis revealed that the SH strain belonged to subtype G2b and has a unique 12-aa deletion (aa 399-410) including the antigenic epitope NEP-1C9 (aa 398-406) of the N protein. PEDV SH strain is highly pathogenic to challenged newborn piglets, resulting in 100 % morbidity and mortality. Pathological examination revealed significant villus atrophy in the jejuna of infected piglets. Mice inoculated with inactivated PEDV SH produced antibodies against the N protein, but no antibodies against the deletions. These results illustrated that deletion of the NEP-1C9 epitope had no effect on the immunogenicity or pathogenicity of PEDV, providing evidence of the necessity to monitor the genetic diversity of the virus. Our study also contributes to development of candidate for vaccines and diagnostics that could differentiate pigs seropositive due to vaccination by conventional strains from wild virus infection.

2.
ACS Appl Mater Interfaces ; 11(12): 11699-11705, 2019 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-30839190

RESUMO

Carbon nanotube (CNT) thin-film transistors are expected to be promising for use in flexible electronics including flexible and transparent integrated circuits and in wearable chemical and physical sensors and for driving the circuits of flexible display panels. However, current devices based on CNT channels suffer from poor performance uniformity and low manufacturing yield; therefore, they are still far from being practical. This is usually caused by nonuniform deposition of the semiconducting CNTs and the rough surface of flexible substrates. Here, we report CNT thin-film transistors (TFTs) driving a flexible 64 × 64 pixel active matrix light-emitting diode display (AMOLED) by improving the formation of uniform CNT films and developing a new pretreatment technique for flexible substrates. The achieved AMOLED has uniform brightness and a high yield of 99.93% in its 4096 pixels. More than 8000 TFTs with high-purity semiconducting CNTs as the channel material show an average on-off current ratio of ∼107 and a carrier mobility of 16 cm2 V-1 s-1. The standard deviations of the on-state current and the carrier mobility are 4.1 and 6.5%, respectively. Our result shows that the panel driven by high-purity semiconducting CNTs is a promising strategy for the development of next-generation flexible, large-area displays.

3.
Cell Physiol Biochem ; 47(4): 1453-1464, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29940559

RESUMO

BACKGROUND/AIMS: Uncaria rhynchophylla, known as "Gou-teng", is a traditional Chinese medicine (TCM) used to extinguish wind, clear heat, arrest convulsions, and pacify the liver. Although U. rhynchophylla has a long history of being often used to treat central nervous system (CNS) diseases, its efficacy and potential mechanism are still uncertain. This study investigated neuroprotective effect and the underlying mechanism of U. rhynchophylla extract (URE) in MPP+-induced SH-SY5Y cells and MPTP-induced mice. METHODS: MPP+-induced SH-SY5Y cells and MPTP-induced mice were used to established Parkinson's disease (PD) models. Quantitative proteomics and bioinformatics were used to uncover proteomics changes of URE. Western blotting was used to validate main differentially expressed proteins and test HSP90 client proteins (apoptosis-related, autophagy-related, MAPKs, PI3K, and AKT proteins). Flow cytometry and JC-1 staining assay were further used to confirm the effect of URE on MPP+-induced apoptosis in SH-SY5Y cells. Gait analysis was used to detect the behavioral changes in MPTP-induced mice. The levels of dopamine (DA) and their metabolites were examined in striatum (STR) by HPLC-EC. The positive expression of tyrosine hydroxylase (TH) was detected by immunohischemical staining and Western blotting. RESULTS: URE dose-dependently increased the cell viability in MPP+-induced SH-SY5Y cells. Quantitative proteomics and bioinformatics results confirmed that HSP90 was an important differentially expressed protein of URE. URE inhibited the expression of HSP90, which further reversed MPP+-induced cell apoptosis and autophagy by increasing the expressions of Bcl-2, Cyclin D1, p-ERK, p-PI3K p85, PI3K p110α, p-AKT, and LC3-I and decreasing cleaved caspase 3, Bax, p-JNK, p-p38, and LC3-II. URE also markedly decreased the apoptotic ratio and elevated mitochondrial transmembrane potential (DΨm). Furthermore, URE treatment ameliorated behavioral impairments, increased the contents of DA and its metabolites and elevated the positive expressions of TH in SN and STR as well as the TH protein. CONCLUSIONS: URE possessed the neuroprotective effect in vivo and in vitro, regulated MAPK and PI3K-AKT signal pathways, and inhibited the expression of HSP90. U. rhynchophylla has potentials as therapeutic agent in PD treatment.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Proteínas de Choque Térmico HSP90/biossíntese , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Transtornos Parkinsonianos , Uncaria/química , Animais , Linhagem Celular Tumoral , Medicamentos de Ervas Chinesas/química , Humanos , Camundongos , Fármacos Neuroprotetores/química , Transtornos Parkinsonianos/tratamento farmacológico , Transtornos Parkinsonianos/metabolismo , Transtornos Parkinsonianos/patologia , Proteômica
4.
Talanta ; 167: 158-165, 2017 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-28340706

RESUMO

The popularity of capillary electrochromatography (CEC) has led to an increasing number of studies on the development and evaluation of enantioselective CEC systems. Herein, a novel, simple, and economical method for the preparation of chiral stationary phases for enantioselective open tubular capillary electrochromatography (OTCEC) was reported for the first time. This novel capillary column was fabricated through layer-by-layer self-assembly of GNPs on a 3-mercaptopropyl-trimethoxysilane (MPTMS)-modified fused-silica capillary and subsequent surface functionalization of the GNPs through self-assembly of thiols ß-cyclodextrin (SH-ß-CD). With this method, monolayer and multilayer GNPs film capillary columns were prepared and evaluated using meptazinol and its three intermediate enantiomers as templates. Consequently, the three-layer GNPs capillary column was found to exhibit favorable enantioseparation performance. Factors that influence the chiral separation resolution were examined. Under the optimized conditions, enantioselectivity was obtained for meptazinol and its three intermediate enantiomers (intermediates Ⅱ, Ⅲ and Ⅳ) in less than 20min with resolutions of 2.05, 0.36, 1.67, 1.53, respectively. The proposed column revealed adequate repeatability concerning run-to-run and day-to-day. In brief, these results confirmed the use of GNPs as the electrochromatographic support can enhance the phase ratio of OTC column in capillary electrochromatography (CEC). Then, this proposed method was well validated with good linearity (≥0.999), recovery (92.0-94.5%) and repeatability, and was successfully used for enantioseparation of meptazinol in spiked urine samples, which indicated the new column's potential usage in biological analysis.


Assuntos
Eletrocromatografia Capilar/métodos , Ouro/química , Nanopartículas Metálicas/química , Compostos de Sulfidrila/química , beta-Ciclodextrinas/química , Álcoois Graxos/química , Concentração de Íons de Hidrogênio , Dióxido de Silício/química , Estereoisomerismo
5.
J Virol Methods ; 234: 96-100, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27091097

RESUMO

The stable HBV-replicating cell lines, which carry replication-competent HBV genome stably integrated into the genome of host cell, are widely used to evaluate the effects of antiviral agents. However, current methods to generate HBV-replicating cell lines, which are mostly dependent on random integration of foreign DNA via plasmid transfection, are less-efficient and time-consuming. To address this issue, we constructed an all-in-one Sleeping Beauty transposon system (denoted pTSMP-HBV vector) for robust generation of stable cell lines carrying replication-competent HBV genome of different genotype. This vector contains a Sleeping Beauty transposon containing HBV 1.3-copy genome with an expression cassette of the SV40 promoter driving red fluorescent protein (mCherry) and self-cleaving P2A peptide linked puromycin resistance gene (PuroR). In addition, a PGK promoter-driven SB100X hyperactive transposase cassette is placed in the outside of the transposon in the same plasmid.The HBV-replicating stable cells could be obtained from pTSMP-HBV transfected HepG2 cells by red fluorescence-activated cell sorting and puromycin resistant cell selection within 4-week. Using this system, we successfully constructed four cell lines carrying replication-competent HBV genome of genotypes A-D. The replication and viral protein expression profiles of these cells were systematically characterized. In conclusion, our study provides a high-efficiency strategy to generate HBV-replicating stable cell lines, which may facilitate HBV-related virological study.


Assuntos
Vírus da Hepatite B/fisiologia , Transposases/genética , Replicação Viral , Técnicas de Cultura , Replicação do DNA , Citometria de Fluxo , Técnicas de Transferência de Genes , Vetores Genéticos , Células HeLa , Células Hep G2 , Vírus da Hepatite B/genética , Humanos , Proteínas Luminescentes
6.
J Virol Methods ; 228: 55-9, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26615806

RESUMO

Hepatitis B virus surface antigen (HBsAg) is an important biomarker used in the diagnosis of hepatitis B virus (HBV) infection, but false-negative results are still reported in the detection of HBsAg using commercial assays. In this study, we evaluated the qualitative properties of a novel HBsAg chemiluminescence enzyme immunoassay (CLEIA) assay--WTultra. WHO standard sample dilution series and samples from low-level HBsAg carriers (<1 ng/mL) were used to evaluate the sensitivity of the WTultra assay. Boston Biomedica, Inc. (BBI) hepatitis B seroconversion panels were used to assess the ability of the WTultra assay to detect the window period. In addition, dilution series of 22 serum samples with different genotypes, serotypes and HBsAg mutations were used to assess the WTultra assay, and these were compared with other commercial assays. The lower detection limit of the WTultra assay was 0.012 IU/mL, and it showed a high sensitivity (97.52%, 95% CI, 94.95-99.00) in the detection of 282 low-level HBsAg carriers (<1 ng/mL). In samples with various HBV genotypes, serotypes and HBsAg mutations, the WTultra assay yielded 117 positive results in 132 samples, which was significantly higher than the results with the other four commercial assays (89, 83, 65 and 45, respectively, p<0.01). In the assays of mutant strains, the WTultra assay detected 82 positive results in 90 samples, which was significantly better than the results for the Hepanostika HBsAg Ultra (58 positive) and Architect (55 positive) (p<0.01) assays, which in turn were significantly better than the Murex V.3 (41 positive, p=0.026) and AxSYM V2 (29 positive, p<0.01) assays. However, in the detection of 42 samples of wild-type strains with various genotypes and serotypes, no significant differences were observed among the WTultra (35 positive), Architect (28 positive) and Hepanostika HBsAg Ultra (31 positive) assays. However, the WTultra assay detected significantly more samples than the Murex V.3 (24 positive, p<0.01) and AxSYM V2 (16 positive, p<0.01) assays. In conclusion, the WTultra HBsAg assay has a high detection sensitivity and presents excellent results for the detection of mutants.


Assuntos
Antígenos de Superfície da Hepatite B/sangue , Hepatite B/diagnóstico , Técnicas Imunoenzimáticas , DNA Viral/genética , Genótipo , Hepatite B/virologia , Antígenos de Superfície da Hepatite B/genética , Antígenos de Superfície da Hepatite B/imunologia , Vírus da Hepatite B/imunologia , Humanos , Técnicas Imunoenzimáticas/instrumentação , Técnicas Imunoenzimáticas/métodos , Limite de Detecção , Medições Luminescentes/instrumentação , Medições Luminescentes/métodos , Mutação , Sensibilidade e Especificidade , Sorogrupo
7.
Anal Chem ; 87(10): 5173-80, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25892477

RESUMO

Hepatitis B virus (HBV) genotyping plays an important role in the clinical management of chronic hepatitis B (CHB) patients. However, the current nucleic acid based techniques are expensive, time-consuming, and inconvenient. Here, we developed a novel DNA-independent HBV genotyping tool based on a one-step fluorescent lateral flow immunoassay (LFIA). Epitope-targeting immunization and screening techniques were used to develop HBV genotype specific monoclonal antibodies (mAbs). These mAbs were used to develop a multitest LFIA with a matched scanning luminoscope for HBV genotyping (named the GT-LFIA). The performance of this novel assay was carefully evaluated in well-characterized clinical cohorts. The GT-LFIA, which can specifically differentiate HBV genotypes A, B, C, and D in a pretreatment-free single test, was successfully developed using four genotype specific mAbs. The detection limits of the GT-LFIA for HBV genotypes A, B, C, and D were 2.5-10.0 IU HBV surface antigen/mL, respectively. Among the sera from 456 CHB patients, 439 (96.3%; 95% confidence interval (CI), 94.1-97.8%) were genotype-differentiable by the GT-LFIA and 437 (99.5%; 95% CI, 98.4-99.9%) were consistent with viral genome sequencing. In the 21 patients receiving nucleos(t)ide analogue therapy, for end-of-treatment specimens that were HBV DNA undetectable and were not applicable for DNA-dependent genotyping, the GT-LFIA presented genotyping results that were consistent with those obtained in pretreatment specimens by viral genome sequencing and the GT-LFIA. In conclusion, the novel GT-LFIA is a convenient, fast, and reliable tool for differential HBV genotyping, especially in patients with low or undetectable HBV DNA levels.


Assuntos
Técnicas de Genotipagem/métodos , Vírus da Hepatite B/genética , Imunoensaio/métodos , Sequência de Aminoácidos , Anticorpos Monoclonais/química , Anticorpos Monoclonais/imunologia , Especificidade de Anticorpos , Antígenos de Superfície da Hepatite B/análise , Antígenos de Superfície da Hepatite B/imunologia , Vírus da Hepatite B/imunologia , Vírus da Hepatite B/fisiologia , Hepatite B Crônica/virologia , Humanos , Dados de Sequência Molecular , Espectrometria de Fluorescência , Fatores de Tempo
8.
Theranostics ; 5(3): 218-26, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25553110

RESUMO

A recent study revealed that quantitative hepatitis B core antibody (qAnti-HBc) level could serve as a novel marker for predicting treatment response. In the present study, we further investigated the predictive value of qAnti-HBc level in HBeAg-positive patients undergoing PEG-IFN therapy. A total of 140 HBeAg-positive patients who underwent PEG-IFN therapy for 48 weeks and follow-up for 24 weeks were enrolled in this study. Serum samples were taken every 12 weeks post-treatment. The predictive value of the baseline qAnti-HBc level for treatment response was evaluated. Patients were further divided into 2 groups according to the baseline qAnti-HBc level, and the response rate was compared. Additionally, the kinetics of the virological and biochemical parameters were analyzed. Patients who achieved response had a significantly higher baseline qAnti-HBc level (serological response [SR], 4.52±0.36 vs. 4.19±0.58, p=0.001; virological response [VR], 4.53±0.35 vs. 4.22±0.57, p=0.005; combined response [CR], 4.50±0.36 vs. 4.22±0.58, p=0.009)). Baseline qAnti-HBc was the only parameter that was independently correlated with SR (p=0.008), VR (p=0.010) and CR(p=0.019). Patients with baseline qAnti-HBc levels ≥30,000 IU/mL had significantly higher response rates, more HBV DNA suppression, and better hepatitis control in PEG-IFN treatment. In conclusion, qAnti-HBc level may be a novel biomarker for predicting treatment response in HBeAg-positive patients receiving PEG-IFN therapy.


Assuntos
Monitoramento de Medicamentos/métodos , Anticorpos Anti-Hepatite B/sangue , Antígenos do Núcleo do Vírus da Hepatite B/imunologia , Antígenos E da Hepatite B/sangue , Hepatite B Crônica/diagnóstico , Hepatite B Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Adulto , Biomarcadores/sangue , DNA Viral/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Carga Viral , Adulto Jovem
9.
Clin Vaccine Immunol ; 21(11): 1521-7, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25209557

RESUMO

Hepatitis B surface antigen (HBsAg) quantification has garnered attention because of its high predictive value in determining treatment responses. The HBsAg quantification assays, such as Architect and Elecsys, are commercially available, and more assays are in development. We aimed to compare the results of the Architect and Elecsys assays with those of a new assay, WTultra. The WTultra HBsAg assay is a sandwich chemiluminescent microplate enzyme immunoassay and provides an alternative choice which is more cost-effective and potentially applicable in developing or resource-constrained countries and areas. A total of 411 serum samples were collected from patients during various phases of chronic hepatitis B (CHB) infection. The samples were assessed using the three assays, and the results were compared and analyzed. The results for the Architect, Elecsys, and WTultra assays were well correlated according to the overall results for the samples (correlation coefficients, rArchitect versus WTultra = 0.936, rArchitect versus Elecsys = 0.952, and rWTultra versus Elecsys = 0.981) and the various infection phases (rArchitect versus WTultra ranging from 0.67 to 0.975, rArchitect versus Elecsys ranging from 0.695 to 0.982, and rWTultra versus Elecsys ranging from 0.877 to 0.99). Additionally, consistent results were observed according to genotype (genotype B: rArchitect versus WTultra = 0.976, rArchitect versus Elecsys = 0.978, and rWTultra versus Elecsys = 0.979; genotype C: rArchitect versus WTultra = 0.950, rArchitect versus Elecsys = 0.963, and rWTultra versus Elecsys = 0.981) and hepatitis B virus (HBV) DNA levels (rArchitect = 0.540, rWTultra = 0.553, and rElecsys = 0.580). In conclusion, the Elecsys and WTultra assays were well correlated with the Architect assay, irrespective of the CHB infection phase or genotype. All of these assays are reliable for HBsAg quantification.


Assuntos
Antígenos de Superfície da Hepatite B/sangue , Hepatite B Crônica/virologia , Medições Luminescentes/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Feminino , Humanos , Imunoensaio/métodos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
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