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1.
J Cell Physiol ; 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-32020591

RESUMO

Long noncoding RNAs (lncRNAs) have been reported to dysregulate and involve in the pathology of hepatocellular carcinoma (HCC). Nonetheless, the functional role of lncRNA T cell leukemia/lymphoma 6 (TCL6) and its underlying mechanism in HCC remain unclear. Herein, we analyzed the expression of TCL6 and elucidated its mechanistic involvement in HCC. Bioinformatics analyses indicated TCL6 was evidently downregulated in HCC tissues compared with normal controls. TCL6 was downregulated while microRNA-106a-5p (miR-106a-5p) was upregulated in HCC cell lines. Moreover, knockdown or overexpression of TCL6 significantly raised or diminished the expression level of miR-106a-5p in HCC cells, similar to the effect of miR-106a-5p on TCL6 expression. Functionally, TCL6 inhibited the proliferative, migratory, and invasive potentials of HCC cells as analyzed by cell counting kit-8, scratch wound healing, and transwell assays, respectively. Conversely, miR-106a-5p exerted an opposite effect on the proliferative, migratory, and invasive potentials of HCC. RNA immune precipitation and luciferase reporter assays revealed TCL6 directly bound to miR-106a-5p and luciferase reporter assay verified phosphatase and tensin homolog (PTEN) was a target gene of miR-106a-5p. Mechanistically, TCL6 knockdown evidently reduced PTEN expression at both messenger RNA and protein levels, and miR-106a-5p inhibitor partially rescued this reduction effect in HCC cells. Additionally, western blot assays demonstrated miR-106a-5p downregulation or TCL6 overexpression promoted the protein level of PTEN, and suppressed the phosphorylation level of AKT, the protein level of phosphatidylinositol 3-kinase (PI3K). Collectively, these results revealed TCL6 as a tumor-suppressive lncRNA regulates PI3K/AKT signaling pathway via directly binding to miR-106a-5p in HCC. This mechanism provides a theoretical basis for HCC pathogenesis and a potential therapeutic strategy for HCC treatment.

2.
Dig Dis Sci ; 2020 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-31974911

RESUMO

BACKGROUND AND AIMS: Acute pancreatitis (AP) is a severe pancreatic disorder that remains associated with high mortality due to a lack of effective drugs and management strategies. This study aimed to investigate the molecular pathogenic mechanisms of AP involving p53 and endoplasmic reticulum (ER) stress pathways. METHODS: Expression of PRSS1 and p53 in human AP tissues was detected by immunohistochemistry and Western blotting. AP was induced with caerulein in humanized PRSS1 transgenic mice, and its severity was verified by histological imaging, evaluation of edema, serum amylase, and trypsin activity assays. A transferase-mediated d-UTP nick end-labeling assay was performed to evaluate acinar cell apoptosis associated with AP. The expression of ER stress genes was assessed by quantitative RT-PCR (qRT-PCR) and Western blotting. RESULTS: PRSS1 and p53 were highly expressed in human AP tissues. Expression of human PRSS1 in caerulein-treated mice induced significant acinar cell apoptosis and AP progression. P53 knockout significantly suppressed AP progression in humanized PRSS1 transgenic mice. The ER stress pathway was activated by PRSS1 and mediated the progression of AP in mouse pancreatic tissues. Application of a p53 inhibitor effectively ameliorated caerulein-induced AP in PRSS1 transgenic mice, while a p53 activator promoted the progression of AP. CONCLUSION: P53, which was activated by the ER stress pathway, promoted the progression of AP in mice expressing PRSS1 by inducing acinar cell apoptosis.

3.
Biosens Bioelectron ; 137: 222-228, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31121459

RESUMO

Electrochemically active bacteria (EAB) use extracellular electron transfer (EET) to exchange electron with extracellular acceptors. Previous studies regarding the measurement of EAB were based on either extracellular reduction or oxidation. In this work, we developed a simple electrochemiluminescence (ECL) assay for the identification and detection of EAB. The results of this proposed method revealed that EET of EAB influenced the content of dissolved oxygen and the formation of Ru(bpy)32+• thus leading to qualitative changes of the ECL signal. EAB with the ability of extracellular reduction (such as Shewanella oneidensis MR-1) gave enhanced signal on ECL emission while those displaying the ability of extracellular oxidation (i.e., Sulfobacillus acidophilus) showed the opposite effect on ECL emission, but non-EAB (i.e., Escherichia coli) did not. These changes in ECL intensity were also proportional to the cell density that could be quantitatively detected in the concentration range of (1.1 ±â€¯1) × 105-212 ±â€¯2 CFU/mL (i.e. Shewanella oneidensis MR-1). Moreover, the measurement of the ability of EAB using this approach was in agreement with measurements using the dissimilatory Fe(III) reduction method. Compared to previous reports, this method displayed a continual and steady ECL signal that allowed accurate measurements of EAB. Most important, only a low cell density was needed in this Ru(bpy)32+ - based ECL method, which is beneficial for cell detection.


Assuntos
Técnicas Biossensoriais , Contagem de Células/métodos , Compostos Férricos/química , Shewanella/isolamento & purificação , Técnicas Eletroquímicas , Transporte de Elétrons , Medições Luminescentes , Fotometria , Shewanella/química
4.
Biosens Bioelectron ; 131: 274-279, 2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-30849727

RESUMO

Nucleic acid nanoswitches have a status that cannot be ignored in the field of biosensing due to the excellent biocompatibility and flexibility of design. In our current research, we have constructed a new electrochemical platform based on self-assembled pH-sensitive continuous circular DNA nanoswitch for miRNA-21 detection. We elaborately designed an inside ring probe (IRP) which could form a circle when complemented with an outside ring probe (ORP). Under the weakly acidic condition, IRPs and ORPs are self-assembled into continuous annular DNA, meanwhile, the nanoswitch is activated. However, if it is not a weakly acidic environment with a pH equal to 6, these circles are separated and the nanoswitch cannot be triggered. Therefore, the biosensor doesn't work. Only when the pH is 6, can the nanoswitch be activated. Consequently, a large number of RuHex will accumulate on the continuous annular DNA, which leads to highly sensitive detection of miRNA-21, with concentration ranged from 10-15 to 10-8 M and limit of detection down to 0.84 fM. More importantly, this nanoswitch-based biosensor can directly detect the target microRNA in human serum without pretreatment. Therefore, the proposed novel electrochemical DNA nanoswitch will have broad application prospects in biomarker detection and clinical diagnosis.


Assuntos
Técnicas Biossensoriais , DNA Circular/química , Técnicas Eletroquímicas , MicroRNAs/isolamento & purificação , Humanos , Concentração de Íons de Hidrogênio , Limite de Detecção , MicroRNAs/química
5.
Talanta ; 191: 277-282, 2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30262063

RESUMO

Detection of specific genes related to drug action can provide scientific guidance for personalized medicine. Taking the detection of a single-nucleotide polymorphism (SNP) genotyping related to the chronic hepatitis B virus (HBV) therapy as an example, a novel biosensor with high sensitivity and selectivity was developed based on the hyperbranched rolling circle amplification (HRCA) in this work. The single-base mutant DNA (mutDNA) sequence can perfectly hybridize with the specially designed discrimination padlock probe and initiate the HRCA reaction. Subsequently, a great abundant of double-strand DNA sequences were released and a strong fluorescence signal can be detected after adding SYBR Green I. In particular, the enhanced fluorescence intensity exhibits a linear relationship with the logarithm of mutDNA concentration ranging from 0.1 nM to 40 nM with a low detection limit of 0.05 nM. However, when there was even a single base mismatch in the target DNA, the HRCA was suppressed and fluorescence response process could not occur, resulting in a high selectivity of this biosensor. Moreover, this detection strategy also performs well in human serums, demonstrating its potential application in detecting SNPs in real biological samples.


Assuntos
Técnicas Biossensoriais/métodos , Fluorescência , Técnicas de Genotipagem/métodos , Hepatite B Crônica/genética , Hepatite B Crônica/terapia , Técnicas de Amplificação de Ácido Nucleico , Polimorfismo de Nucleotídeo Único , Humanos , Limite de Detecção
7.
J Huazhong Univ Sci Technolog Med Sci ; 35(2): 278-282, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25877365

RESUMO

The factors influencing the incidence of common complications (pneumothorax and pulmonary hemorrhage) of CT-guided percutaneous needle biopsy of lumps near pulmonary hilum were investigated. CT-guided percutaneous needle biopsy of lumps near pulmonary hilum was performed on 48 patients. The complications of pneumothorax and pneumorrhagia as well as the contributing factors were analyzed statistically. The major complications associated with CT-guided needle biopsy included pneumothorax (13 cases, 27.1%) and pulmonary hemorrhage (14 cases, 20.24%). χ(2) test revealed that pneumothorax was associated with the lesion size and depth of needle penetration, and pulmonary hemorrhage with the depth of needle penetration and needle retention time with a significant P value. Pneumothorax was observed in 7 cases (17.5%) out of 40 cases with diameter of mass greater than 3 cm, and in 6 cases (60%) out of 10 cases with depth of needle penetration greater than 4 cm. Additionally, pulmonary hemorrhage was identified in 12 cases (41.4%) out of 29 cases with needle retention time longer than 15 min, and pulmonary hemorrhage in 7 cases (70%) out of 10 cases with depth of needle penetration greater than 4 cm. CT-guided percutaneous needle biopsy of lumps near pulmonary hilum is safe and effective. The key factors to prevent the complications include correct evaluation of lesion size, depth of needle penetration and the needle retention time before the operation.


Assuntos
Biópsia por Agulha/efeitos adversos , Neoplasias Pulmonares/patologia , Biópsia por Agulha/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Tomografia Computadorizada por Raios X
8.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(11): 3092-5, 2015 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-26978915

RESUMO

Chrysoidin is a kind of banned food dye, and it has been illegally used for coloring food. A rapid detection and quantification method is developed and applied in analysis chrysoidin in yuba. Gold nanoparticles are synthesized by using hexadecyl trimethyl ammonium bromide (CTAB) as the bifunctional ligand to link the solid substrate and the AuNPs. The laser wavelength used for quantitative is 1594 cm⁻¹. Significant differences between different concentrations of chrysoidin are verified by multiple variable analysis. A relationship between the logarithm of the concentrations and the intensity of laser is proved using univariate analysis method. The calibration curves showed good linearity in the range of 0.001-0.5 mmol · L⁻¹ with correlation coefficients r = 0.995. The method is successfully applied to the determination of chrysoidin in yuba. The average recoveries of the drugs spiked at 50 and 500 µg · g⁻¹ levels are 82.4% and 116.9%, and the relative standard deviations (RSD) are 3.8% and 4.0%. The method is simple, rapid, sensitive and accurate in the determination of chrysoidin.


Assuntos
Corantes de Alimentos/análise , Ouro/química , Nanopartículas Metálicas/química , p-Aminoazobenzeno/análogos & derivados , Análise Espectral Raman , p-Aminoazobenzeno/análise
9.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(3): 656-9, 2014 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-25208385

RESUMO

The present paper presented a fast and non-destructive method for the discrimination of minnan oolong tea varieties by near-infrared spectroscopy technology. Two hundred ten samples including Tieguanyin, Huangjingui, Benshan, Maoxie and Meizhan were collected in different tea plantations of Minnan. NIR spectra of 1,100-1,300 nm and 1,640-2,498 nm were successfully obtained. Prediction model was built by principal component analysis (PCA), and the effects of multiplicative scatter correction (MSC) and standard normal variate (SNV) on the model were observed and compared. It was indicated that the effect of MSC on the model was superior for the effect of SNV because the classification accuracy of model for the calibration samples reached 96%, and this number to the prediction samples was about 90%. These results demonstrated that the near-infrared spectroscopy method established could be an efficient and accurate way for the discrimination of minnan oolong teas and would have a strong practical value.


Assuntos
Análise de Alimentos , Espectroscopia de Luz Próxima ao Infravermelho , Chá/classificação , Modelos Teóricos , Análise de Componente Principal
10.
World J Pediatr ; 10(1): 10-6, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24464658

RESUMO

BACKGROUND: Neuroblastoma (NB) is the most common extracranial solid tumor in childhood and displays remarkable heterogeneity in clinical behaviors, ranging from spontaneous regression to rapid progression or resistance to multimodal treatment. Recent evidence has shown that microRNAs (miRNAs), a class of small non-coding RNAs, are involved in tumor development and progression. This article aimed to review recent advances in investigating the roles of miRNAs in NB. METHODS: We searched the PubMed/MEDLINE database for articles about the expression profile, functions and target genes of miRNAs in NB. RESULTS: We reviewed the most recent evidence regarding the functional roles of oncogenic and tumor suppressive miRNAs in NB and application of novel miRNA-based methods for diagnostic, prognostic and therapeutic purposes. CONCLUSIONS: Deregulation of miRNAs is associated with the development and progression of NB, suggesting that miRNAs may serve as novel targets for the treatment of high-risk NB patients. However, their precise functions and underlying mechanisms still warrant further studies.


Assuntos
MicroRNAs/genética , Neuroblastoma/genética , Criança , Progressão da Doença , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , MicroRNAs/metabolismo , Neuroblastoma/metabolismo , Prognóstico
11.
Guang Pu Xue Yu Guang Pu Fen Xi ; 33(3): 690-3, 2013 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-23705434

RESUMO

Based on the initial near-infrared spectrum of edible essence samples and its mixture with DEHP and DINP, we chose the wavelength ranges of 8,800 - 8,540 and 7,500 - 5,085 cm-1 to use the principal component analysis (PCA) method to distinguish these three types of samples. The correct rate of the identification is proved to be 100%. Meanwhile, we measured the content of DEHP and DINP (with the concentration ranging between 0 and 100 mg.kg-1) in the edible essence and established the quantitative analysis model by using partial least squares (PLS). It was found that the relative errors of the prediction results of DEHP and DINP are -1.23% - 3% and -1% - 3.6%, respectively, and the relative root-mean-square errors of prediction (RRMSEP) of them are 1.39 and 0.98, respectively. This study provides a simple, rapid and accurate method to detect the additive dosage of plasticizing agents in edible essence in the food industry.


Assuntos
Contaminação de Alimentos/análise , Óleos Voláteis/química , Plastificantes/análise , Espectrofotometria Infravermelho/métodos , Análise dos Mínimos Quadrados , Análise de Componente Principal , Espectrofotometria Infravermelho/instrumentação
12.
Biosens Bioelectron ; 41: 168-71, 2013 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-22959013

RESUMO

In this paper, we reported a convenient fluorescence method for the detection of genetically modified organisms (GMOs). As it is known that the cauliflower mosaic virus (CaMV) 35S promoter is widely used in most transgenic plants (Schnurr and Guerra, 2000), we thus design a simple method based on the detection of a section target DNA (DNA-T) from the transgene CaMV 35S promoter. In this method, the full-length guanine-rich single-strand sequences were split into fragments (Probe 1 and 2) and each part of the fragment possesses two GGG repeats. In the presence of K(+) ion and berberine, if a complementary target DNA of the CaMV 35S promoter was introduced to hybridize with Probe 1 and 2, a G-quadruplex-berberine complex was thus formed and generated a strong fluorescence signal. The generation of fluorescence signal indicates the presence of CaMV 35S promoter. This method is able to identify and quantify Genetically Modified Organisms (GMOs), and it shows wide linear ranges from 5.0×10(-9) to 9.0×10(-7) mol/L with a detection limit of 2.0×10(-9) mol/L.


Assuntos
Técnicas Biossensoriais/instrumentação , Caulimovirus/genética , DNA de Plantas/genética , DNA Viral/genética , Plantas Geneticamente Modificadas/classificação , Plantas Geneticamente Modificadas/genética , Regiões Promotoras Genéticas/genética , Espectrometria de Fluorescência/instrumentação , DNA de Plantas/análise , DNA Viral/análise , Desenho de Equipamento , Análise de Falha de Equipamento , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Transgenes/genética
13.
Chem Commun (Camb) ; 47(5): 1437-9, 2011 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-21165489

RESUMO

A novel fluorescent sensor for detection of genetically modified organisms was developed, and in the sensor G-quadruplex DNAzyme (G-quadruplex-hemin complex) was used as the turn on switch.


Assuntos
DNA Catalítico/química , Quadruplex G , Hemina/química , Organismos Geneticamente Modificados , Dicroísmo Circular , Fluorescência , Espectrofotometria Ultravioleta
14.
J Control Release ; 144(2): 190-5, 2010 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-20184932

RESUMO

BMP-2 is one of the most important growth factors of bone regeneration. Polylactide-co-glycolic acid (PLGA), which is used as a biodegradable scaffold for delivering therapeutic agents, has been intensively investigated. In previous studies, we synthesized a novel BMP-2-related peptide (designated P24) and found that it could enhance the osteoblastic differentiation of bone marrow stromal cells (BMSCs). The objective of this study was to construct a biomimetic composite by incorporating P24 into a modified PLGA-(PEG-ASP)n copolymer to promote bone formation. In vitro, our results demonstrated that PLGA-(PEG-ASP)n scaffolds were shown to be an efficient system for sustained release of P24. Significantly more BMSCs attached to the P24/PLGA-(PEG-ASP)n and PLGA-(PEG-ASP)n membranes than to PLGA, and the cells in the two groups subsequently proliferated more vigorously than those in the PLGA group. The expression of osteogenic markers in P24/PLGA-(PEG-ASP)n group was stronger than that in the PLGA-(PEG-ASP)n and PLGA groups. Radiographic and histological examination, Western blotting and RT-PCR showed that P24/PLGA-(PEG-ASP)n scaffold could induce more effective ectopic bone formation in vivo, as compared with PLGA-(PEG-ASP)n or gelatin sponge alone. It is concluded that the PLGA-(PEG-ASP)n copolymer is a good P24 carrier and can serve as a good scaffold for controlled release of P24. This novel P24/PLGA-(PEG-ASP)n composite promises to be an excellent biomaterial for inducing bone regeneration.


Assuntos
Regeneração Óssea/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Animais , Asparaginase , Materiais Biocompatíveis/metabolismo , Biomimética , Proteína Morfogenética Óssea 2 , Osso e Ossos/metabolismo , Diferenciação Celular/efeitos dos fármacos , Durapatita/metabolismo , Glicolatos , Masculino , Células-Tronco Mesenquimais/metabolismo , Peptídeos/metabolismo , Poliésteres , Polietilenoglicóis , Polímeros/metabolismo , Distribuição Aleatória , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase Via Transcriptase Reversa
15.
J Chromatogr A ; 1177(1): 195-8, 2008 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-18061199

RESUMO

A capillary electrophoresis (CE) method coupled with electrochemiluminescence (ECL) detection for the analysis of glyphosate (GLY) and its major metabolite aminomethylphosphonic acid (AMPA) is presented. Complete separation of GLY and AMPA was achieved in 8 min using a background electrolyte of 20 mM sodium phosphate (pH 9.0) and a separation voltage of 21 kV. ECL detection was performed with an indium tin oxide (ITO) working electrode bias at 1.6 V (vs. a Pt-wire reference) in a 30 0mM sodium phosphate buffer (pH 8.0) containing 3.5mM Ru(bpy)3 2+ (where bpy=2.2'-bipyridyl). Linear correlation (r>or=0.997) between ECL intensity and analyte concentration was obtained in the ranges 0.169-16.9 and 5.55-111 microg ml(-1) for GLY and AMPA, respectively. The limits of detection (LODs) for GLY and AMPA in water were 0.06 microg ml(-1) and 4.04 microg ml(-1), respectively. The developed method was applied to the analysis of GLY in soybeans. The LOD of GLY in soybean was 0.6 microg g(-1). Total analysis time including sample pretreatment was less than 1h.


Assuntos
Eletroforese Capilar/métodos , Glicina/análogos & derivados , Organofosfonatos/análise , Calibragem , Glicina/análise , Isoxazóis , Luminescência , Plantas Geneticamente Modificadas , Reprodutibilidade dos Testes , Soja/química , Tetrazóis
16.
Guang Pu Xue Yu Guang Pu Fen Xi ; 26(11): 1996-9, 2006 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-17260740

RESUMO

The present paper reports the establishment of an electrochemi-luminescence (ECL) sensor by using screen-printed electrodes(SPE) which contain Ru(bpy)3(2+). The method of making the SPE and the fix of Ru(bpy)3(2+) were studiedin detail. The characters of the sensor were studied. The sensor has been applied to detect C2O4(2-) in solution. Under optimised conditions, at 1.55 V vs. Ag/AgCl, in 0.2 mol x L(-1) phosphate buffer solution (pH 6.0), the linger range extends from 3.0 x 10(-7) mol x L(-1) to 1.0 x 10(-5) mol x L(-1), the detection limit is 1.2 x 10(-7) mol x L(-1) (S/N=3). The sensors have good stability and reproductivity. It should be noted that based on the same principle, the sensors can be applied to detect many other compounds, such as amino acids, TprA and NAD. If the screen machine is used to make the SPE, the reproductivity and stability of the SPEs can be improved further.

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