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1.
J Transl Med ; 20(1): 557, 2022 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-36463222

RESUMO

BACKGROUND: Lymph node metastasis (LNM) is one of the most important factors affecting the prognosis of breast cancer. The accurate evaluation of lymph node status is useful to predict the outcomes of patients and guide the choice of cancer treatment. However, there is still lack of a low-cost non-invasive method to assess the status of axillary lymph node (ALN). Gene expression signature has been used to assess lymph node metastasis status of breast cancer. In addition, nucleosome footprint of cell-free DNA (cfDNA) carries gene expression information of its original tissues, so it may be used to evaluate the axillary lymph node status in breast cancer. METHODS: In this study, we found that the cfDNA nucleosome footprints between the ALN-positive patients and ALN-negative patients showed different patterns by implementing whole-genome sequencing (WGS) to detect 15 ALN-positive and 15 ALN-negative patients. In order to further evaluate its potential for assessing ALN status, we developed a classifier with multiple machine learning models by using 330 WGS data of cfDNA from 162 ALN-positive and 168 ALN-negative samples to distinguish these two types of patients. RESULTS: We found that the promoter profiling between the ALN-positive patients and ALN-negative patients showed distinct patterns. In addition, we observed 1071 genes with differential promoter coverage and their functions were closely related to tumorigenesis. We found that the predictive classifier based on promoter profiling with a support vector machine model, named PPCNM, produced the largest area under the curve of 0.897 (95% confidence interval 0.86-0.93). CONCLUSIONS: These results indicate that promoter profiling can be used to distinguish ALN-positive patients from ALN-negative patients, which may be helpful to guide the choice of cancer treatment.


Assuntos
Neoplasias da Mama , Ácidos Nucleicos Livres , Humanos , Feminino , Neoplasias da Mama/genética , Metástase Linfática/genética , Nucleossomos , Linfonodos , Ácidos Nucleicos Livres/genética
2.
J Fluoresc ; 27(1): 309-316, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27878521

RESUMO

In this paper, a novel time-resolved fluorescence immunoassay (TRFIA) is described that allows the simultaneous quantitative detection of hepatitis B virus surface antigen (HBsAg) and hepatitis B e antigen (HBeAg) in human serum to aid the diagnosis and monitoring of hepatitis B virus infection. The proposed method was developed based on a two-step sandwich immunoassay protocol in which monoclonal antibodies against HBsAg and HBeAg were co-coated in 96 microtitration wells, then tracer polyclonal antibodies against HBsAg labeled with samarium and tracer monoclonal antibodies against HBeAg labeled with europium chelates were used for detection. The detection range was 0.1-150 IU/mL for HBsAg and 0.5-160 PEIU/mL for HBeAg, and the detection limits were 0.03 IU/L and 0.09 PEIU/ml, respectively. The intra- and inter-assay coefficients of variation were below 8 % for both virus antigens. The dilution linearity and accuracy of the assay were satisfactory. No statistically significant differences were observed in sensitivity or specificity for the serum samples between the dual-label TRFIA and a commercial single-label TRFIA. These results demonstrate that an effective, reliable and convenient HBsAg/HBeAg dual-label TRFIA was successfully developed that may be clinically applicable for blood screening to monitor the course of hepatitis B virus infection and predict treatment responses.


Assuntos
Fluorimunoensaio/métodos , Antígenos de Superfície da Hepatite B/sangue , Vírus da Hepatite B/isolamento & purificação , Hepatite B/diagnóstico , China/epidemiologia , Hepatite B/epidemiologia , Hepatite B/virologia , Humanos , Indicadores e Reagentes
3.
J Fluoresc ; 26(3): 987-96, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27034063

RESUMO

The isoenzyme creatine kinase MB is very important for diagnosis of acute myocardial infarction (AMI). Some CK-MB immunoassays are sensitive, accurate and available for clinical application, but they are expensive and time-consuming procedures. Furthermore, conventional fluorescence immunochromatographic assays (FL-ICAs) have suffered from background fluorescence interference and low analytical sensitivity. A rapid and simple FL-ICA with Eu (III) chelate polystyrene microparticles was developed to determine CK-MB in 50uL serum samples using a portable test strip reader by measuring the fluorescence peak heights of the test line (HT) and the control line (HC) in 12 min. The assay was reliable with a good correlation coefficient between HT/HC ratio and CK-MB concentration in samples. A linear range was 0.85-100.29 ng/mL for CK-MB, and the LOD was 0.029 ng/mL. The intra- and inter-assay coefficients of variation (CV) were both <10 % and the average recoveries were from 90.17 % -112.63 % for CK-MB. The system performed well in interference experiments. Furthermore, a highly significant correlation (r = 0.9794, P < 0.001) between this method and the commercially available bioMérieux mini VIDAS system were attained for measuring 120 CK-MB samples. These results indicated that the Eu (III) chelate microparticles-based FL-ICA is simple, fast, highly sensitive, reliable, and reproducible for point-of-care testing of CK-MB concentrations in serum. Graphical Abstract ᅟ.


Assuntos
Quelantes/química , Cromatografia de Afinidade/métodos , Creatina Quinase Forma MB/metabolismo , Európio/química , Microesferas , Cromatografia de Afinidade/instrumentação , Poliestirenos/química , Fitas Reagentes/química , Valores de Referência , Espectrometria de Fluorescência , Fatores de Tempo
4.
J Fluoresc ; 26(1): 317-22, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26563227

RESUMO

The unique photoproperties of quantum dots are promising for potential application in bioassays. In the present study, quantum dots were applied to a luminescent oxygen channeling assay. The reaction system developed in this study was based on interaction of biotin with streptavidin. Carboxyl-modified polystyrene microspheres doped with quantum dots were biotinylated and used as acceptors. Photosensitizer-doped carboxyl-modified polystyrene microspheres were conjugated with streptavidin and used as donors. The results indicated that the singlet oxygen that was released from the donor beads diffused into the acceptor beads. The acceptor beads were then exited via thioxene, and were subsequently fluoresced. To avoid generating false positives, a high concentration (0.01 mg/mL) of quantum dots is required for application in homogeneous immunoassays. Compared to a conventional luminescent oxygen channeling assay, this quantum dots-based technique requires less time, and would be easier to automate and miniaturize because it requires no washing to remove excess labels.


Assuntos
Fluorescência , Corantes Fluorescentes/química , Imunoensaio , Medições Luminescentes , Oxigênio/química , Pontos Quânticos , Corantes Fluorescentes/síntese química , Estrutura Molecular
5.
J Clin Lab Anal ; 30(5): 719-26, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27228385

RESUMO

BACKGROUND: Because of the life-consuming treatment and severe consequences associated with thalassemia, it is more effective to prevent than cure thalassemia. Rapid and sensitive detection is critical for controlling thalassemia. In this study, we developed a rapid and accurate test to genotype nondeletional α- and ß-thalassemia mutations by an electrochemical DNA sensor. METHODS: Screen-printed electrodes were used as electrochemical transducers for the sensor, in which the capture probe DNA was attached to the golden surface of the working electrode via an S-Au covalent bond, which is highly suitable for immobilizing the biological element. In addition, two types of ferrocene with varying redox potentials for modified signal probe DNA were adopted. The hybridization signal is detected by alternating current voltammetry when the capture probe and signal probe hybridize with the target DNA. RESULTS: With this technique, 12 types of nondeletional α- and ß-thalassemia mutations were detected, which constitute more than 90% of all the nondeletional types of thalassemia mutation determinants found in China, including the CD142 (TAA>CAA) Constand spring, CD125 (CTG>CCG) Quonsze, CD122 (CAC>CAG) Weastmead, -28 (A>G), Cap+1 (A>C), initiation codon (ATG>AGG), CD17 (AAG>TAG), CD26 (GAG>AAG), CD31(-C), CD41-42 (-CTTT), CD71-72 (+A), and IVS-II-654 (C>T) mutations. Concordance levels were 100% within the 20 blood samples of homozygous wild-type individuals and 238 blood samples of heterozygous mutant individuals. CONCLUSIONS: The electrochemical DNA sensor developed here can be applied for rapid genotyping of thalassemia or other clinical genotyping applications and is useful for early screening of thalassemia in high-risk groups by minimizing the time and investment cost.


Assuntos
Técnicas Biossensoriais/instrumentação , DNA/análise , Eletroquímica/instrumentação , Eletroquímica/métodos , Talassemia alfa/diagnóstico , Talassemia beta/diagnóstico , China , Primers do DNA/metabolismo , Compostos Ferrosos/química , Homozigoto , Humanos , Metalocenos , Sensibilidade e Especificidade
6.
J Med Virol ; 87(11): 1940-5, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26129643

RESUMO

Enzyme-linked immunosorbent assay (ELISAs) specific for Epstein-Barr virus nuclear antigen 1 (EBNA1)-immunoglobulin A (IgA) are most commonly used in the clinical diagnosis of EBV infection. But they have a low sensitivity and the enzyme-labeled antibodies are unstable. In this study, a novel immunoassay based on an indirect time-resolved fluoroimmunoassay (TRFIA) was developed. Microtiter plates were coated with recombinant EBNA1. We used Eu(3) (+)-labeled anti-human IgA as probe. The precision, sensitivity, specificity, and stability were evaluated, and comparison with traditional and commercially available ELISAs was also made. The cut-off value for our TRFIA was 2.7. Intra- and inter-assay coefficients of variation for the TRFIA were 1.56-4.99% and 3.92-6.95%, respectively; whereas those for the ELISA were 4.54-8.16% and 7.07-10.52%, respectively. Sensitivity was obviously better than traditional ELISA when diluted positive samples serially. Additionally, stability, specificity test and comparison of sensitivity and specificity between the TRFIA and commercial ELISAs all proved satisfactory. In conclusion, the results demonstrated that EBNA1 IgA TRFIA was a sensitive immunoassay and had potential value in large-scale screening of human serum samples in developing countries.


Assuntos
Anticorpos Antivirais/sangue , Infecções por Vírus Epstein-Barr/diagnóstico , Antígenos Nucleares do Vírus Epstein-Barr/imunologia , Imunofluorescência/métodos , Herpesvirus Humano 4/imunologia , Imunoglobulina A/sangue , Infecções por Vírus Epstein-Barr/imunologia , Humanos , Sensibilidade e Especificidade , Soro/química
7.
Luminescence ; 30(5): 649-54, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25377426

RESUMO

Enzyme-linked immunosorbent assays (ELISA) specific for anti-HSV glycoprotein G (gG) are most commonly used in the clinical diagnosis of HSV infection. But most of them are qualitative and with narrow detection ranges. A novel time-resolved fluoroimmunoassay (TRFIA) methodology was developed for the quantitative determination of HSV IgG in human serum. The assay was based on an indirect immunoassay format, and performed in 96-well microtiter plates. HSV-1 and HSV-2 were used as the coating antigens. Eu(3+)-labeled goat anti-(human IgG) polyclonal antibodies were used as tracers. The fluorescence intensity of each well was measured and serum HSV IgG levels quantified against a calibration curve. The detection range of the novel TRFIA was between 5 and 500 AU/mL. Assay sensitivity was 0.568 AU/mL. The intra- and inter-assay coefficients of variation were 0.59-3.63% and 3.65-6.81%, respectively. Analytical recovery, dilution tests and serum panel tests were performed using TRFIA and the results proved satisfactory. There were no statistically significant differences in sensitivity and specificity between the TRFIA and commercial ELISAs. An effective, sensitive and accurate quantitative HSV type 1 and type 2 IgG TRFIA was successfully developed and provided diagnostic value in clinical use.


Assuntos
Anticorpos Antivirais/sangue , Fluorimunoensaio/métodos , Herpesvirus Humano 1/imunologia , Herpesvirus Humano 2/imunologia , Ensaio de Imunoadsorção Enzimática , Herpes Simples/sangue , Herpes Simples/virologia , Humanos , Imunoglobulina G , Sensibilidade e Especificidade
8.
Luminescence ; 29(6): 591-7, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24136927

RESUMO

Current clinically assays, such as enzyme-linked immunosorbent assay and chemiluminescence immunoassay, for hepatitis B surface antigen (HBsAg) are inferior in terms of either sensitivity and accuracy or rapid and high-throughput analysis. A novel assay based on magnetic beads and time-resolved fluoroimmunoassay was developed for the quantitative determination of HBsAg in human serum. HBsAg was captured using two types of anti-HBsAg monoclonal antibodies (B028, S015) immobilized on to magnetic beads and detected using europium-labeled anti-HBsAg polyclonal detection antibody. Finally, the assay yielded a high sensitivity (0.02 IU/mL) and a wide dynamic range (0.02-700 IU/mL) for HBsAg when performed under optimal conditions. Satisfactory accuracy, recovery and specificity were also demonstrated. The intra- and interassay coefficients of variation were 4.7-8.7% and 3.8-7.5%, respectively. The performance of this assay was further assessed against a well-established commercial chemiluminescence immunoassay kit with 399 clinical serum samples. It was revealed that the test results for the two methods were in good correlation (Y = 1.182X - 0.017, R = 0.989). In the current study, we demonstrated that this novel time-resolved fluoroimmunoassay could be used: as a highly sensitive, automated and high-throughput immunoassay for the diagnosis of acute or chronic hepatitis B virus infection; for the screening of blood or organ donors; and for the surveillance of persons at risk of acquiring or transmitting hepatitis B virus.


Assuntos
Antígenos de Superfície da Hepatite B/sangue , Imunoensaio , Fenômenos Magnéticos , Humanos , Luminescência , Fatores de Tempo
9.
Analyst ; 138(13): 3697-704, 2013 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-23671904

RESUMO

In this paper, a novel time-resolved fluoroimmunoassay (TRFIA) protocol using magnetic particles for the simultaneous determination of α-fetoprotein (AFP) and the free ß-subunit of human chorionic gonadotropin (free ß-hCG) in human serum is described. The new approach uses magnetic particles as an immobilization matrix and means of separation, while the luminescent europium and samarium chelates are used as probes. The proposed method was evaluated via a single-step, sandwich-type TRFIA immunoassay of AFP and free ß-hCG as model analytes in serum. With the advantages of magnetic particles, the TRFIA immunoassay exhibited a wide dynamic range for AFP of 0.1-750 ng mL(-1), with a lower detection limit of 0.05 ng mL(-1). The dynamic range for free ß-hCG was 0.16-450 ng mL(-1), with a lower detection limit of 0.08 ng mL(-1). Satisfactory specificity, reproducibility, and recovery of the immunoassay were demonstrated. Good correlations were obtained in the analysis of 446 human serum samples between the proposed method and a commercial TRFIA kit. These results demonstrate the feasibility and potential of the new method as a rapid and highly sensitive immunoassay that could be developed into a platform for multi-analyte determinations in clinical practice.


Assuntos
Gonadotropina Coriônica Humana Subunidade beta/análise , Fluorimunoensaio/métodos , Imãs , alfa-Fetoproteínas/análise , Biomarcadores/sangue , Gonadotropina Coriônica Humana Subunidade beta/sangue , Feminino , Humanos , Gravidez , Reprodutibilidade dos Testes , Fatores de Tempo
10.
J Fluoresc ; 23(4): 649-57, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23471623

RESUMO

Quantum dots are not widely used in clinical diagnosis. However, the homogeneous time-resolved fluorescence assay possesses many advantages over current methods for the detection of carcinoembryonic antigen (CEA), a primary marker for many cancers and diseases. Therefore, a novel luminescent terbium chelates- (LTCs) and quantum dots-based homogeneous time-resolved fluorescence assay was developed to detect CEA. Glutathione-capped quantum dots (QDs) were prepared from oil-soluble QDs with a 565 nm emission peak. Conjugates (QDs-6 F11) were prepared with QDs and anti-CEA monoclonal antibody. LTCs were prepared and conjugates (LTCs-S001) were prepared with another anti-CEA monoclonal antibody. The fluorescence lifetime of QDs was optimized for sequential analysis. The Förster distance (R0) was calculated as 61.9 Å based on the overlap of the spectra of QDs-6 F11 and LTCs-S001. Using a double-antibody sandwich approach, the above antibody conjugates were used as energy acceptor and donor, respectively. The signals from QDs were collected in time-resolved mode and analyzed for the detection of CEA. The results show that the QDs were suitable for time-resolved fluoroassays. The spatial distance of the donor-acceptor pair was calculated to be 61.9 Å. The signals from QDs were proportional to CEA concentration. The standard curve was LogY = 2.75566 + 0.94457 LogX (R = 0.998) using the fluorescence counts (Y) of QDs and the concentrations of CEA (X). The calculated sensitivity was 0.4 ng/mL. The results indicate that water-soluble QDs are suitable for the homogenous immunoassay. This work has expanded future applications of QDs in homogeneous clinical bioassays. Furthermore, a QDs-based homogeneous multiplex immunoassay will be investigated as a biomarker for infectious diseases in future research.


Assuntos
Antígeno Carcinoembrionário/análise , Fluorimunoensaio/métodos , Pontos Quânticos , Água/química , Animais , Quelantes/química , Transferência Ressonante de Energia de Fluorescência , Corantes Fluorescentes/química , Solubilidade , Térbio/química , Fatores de Tempo
11.
J Clin Lab Anal ; 27(4): 277-83, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23852784

RESUMO

BACKGROUND: Cytokeratin 19 fragment antigen (CYFRA 21-1) is used to diagnose and monitor neoplasms. However, the main disadvantages of the currently available CYFRA 21-1 assays include heterogenous technology, being time-consuming, and having low through-put with low insensitivity. This study investigated the use of amplified luminescent proximity homogeneous immunoassay (AlphaLISA) for the quantization of CYFRA 21-1 in human serum. METHODS: The AlphaLISA kit was developed based on AlphaScreen detection technology with two different anti-CYFRA 21-1 monoclonal antibodies. One was coated on AlphaLISA acceptor beads and the other was biotinylated. Donor beads were coated with streptavidin. The test conditions were optimized and analytical performance was studied. RESULTS: The measurement range of AlphaLISA CYFRA 21-1 kit was 0.08-500 ng/ml. Assay detection limit was 0.08 ng/ml. The intra- and interassay coefficients of variation were 3.00-9.00% and 4.00-10.00%, respectively. There was no cross-reaction to alpha-fetoprotein (AFP), carcinoembryonic antigen (CEA), neuron-specific enolase (NSE), cancer antigen 19-9 (CA19-9), cytokeratins 8 (CK8), and cytokeratins 18 (CK18). The correlation coefficient of blood samples involved was 0.974 between CYFRA 21-1-AlphaLISA assay and a commercial electrochemiluminescence immunoassay (ECLIA) CYFRA 21-1 kit (Roche). CONCLUSIONS: The AlphaLISA CYFRA 21-1 kit developed in this study had favorable performance characteristics for clinical application with acceptable analytical sensitivity, specificity, and accuracy.


Assuntos
Antígenos de Neoplasias/sangue , Imunoensaio/métodos , Queratina-19/sangue , Medições Luminescentes/métodos , Biomarcadores Tumorais/sangue , Humanos , Neoplasias Pulmonares/diagnóstico , Kit de Reagentes para Diagnóstico , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
12.
Luminescence ; 28(3): 401-6, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-22715159

RESUMO

Time-resolved fluorometry of lanthanide chelates is one of the most useful non-isotopic detection techniques and has been used in numerous applications in biomedical science. We developed a time-resolved fluoroimmunoassay (TRFIA) to quantify α-fetoprotein (AFP) and hepatitis B virus surface antigen (HBsAg) in human serum. Based on a two-site sandwich protocol, monoclonal antibodies (McAbs) against AFP and HBsAg were co-coated in 96 microtitration wells and tracer McAbs against HBsAg and AFP were labeled with europium (Eu) and samarium (Sm) chelates, respectively. After application of diluted serum samples, Eu(3+)- and Sm(3+)-McAbs were added and fluorescence signals of Sm(3+) and Eu(3+) tracers were collected. Detection limits of AFP and HBsAg were 0.09 mIU/L and 0.01 µg/L, respectively. Measurement ranges of AFP-TRFIA and HBsAg-TRFIA were 1-1000 mIU/L and 0.2-150 µg/L, respectively. Intra- and inter-assay coefficients of variation of AFP-TRFIA were 3.3-4.1% and 5.7-7.2% and for HBsAg-TRFIA were 2.9-3.9% and 4.9-6.8%, respectively. Linear correlation of TRFIA and chemiluminescence immunoassay measurements resulted in a correlation coefficient of 0.9949 for AFP and 0.9940 for HBsAg. For the endurance test, Eu-labeled McAbs were stable for at least one year at -20°C and the results of the TRFIA with the same reagents were also reproducible after one year. The availability of a highly sensitive, reliable and convenient AFP/HBsAg TRFIA will allow the quantification of both AFP and HBsAg, thereby providing diagnostic value in various clinical conditions and could be applied for clinical use.


Assuntos
Fluorimunoensaio/métodos , Antígenos de Superfície da Hepatite B/sangue , Vírus da Hepatite B/química , alfa-Fetoproteínas/análise , Fluorimunoensaio/instrumentação , Hepatite B/sangue , Hepatite B/virologia , Humanos
13.
J Immunoassay Immunochem ; 34(2): 134-48, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23537299

RESUMO

Measurement of the free ß subunit of human chorionic gonadotropin (free ß-hCG) in serum is useful for prenatal screening. Concentrations of free ß-hCG vary in different races. Conventional assays used for such measurements have limitations. We applied the AlphaLISA to measure levels of free ß-hCG in maternal serum during 8-20 weeks of gestation in women from southern China. Two anti-free ß-hCG antibodies were used: one was coated on AlphaLISA acceptor beads and the one was biotinylated. The assay also contained donor beads coated with streptavidin. The AlphaLISA assay detection limit was 0.11 ng/mL, and the analytical range was 0.11-200 ng/mL. The intra- and interassay coefficients of variation were 1.32%-2.50% and 3.44%-5.45%, respectively. The correlation with commercial Eu(3+)-labeled free ß-HCG-TRFIA assay was good (y = 1.045x + 1.580, r(2) = 0.978). Median levels of free ß-hCG in maternal serum at 8-20 weeks gestation were higher in women from southern China compared with those reported in women from other countries. The AlphaLISA for free ß-HCG could become the assay of choice for applications in clinical diagnostics. The established median value of free ß-HCG is helpful in clinical diagnosis specific for southern Chinese women.


Assuntos
Gonadotropina Coriônica Humana Subunidade beta/sangue , Imunoensaio/normas , Primeiro Trimestre da Gravidez/sangue , Primeiro Trimestre da Gravidez/etnologia , Adulto , Povo Asiático , Feminino , Humanos , Limite de Detecção , Gravidez , Diagnóstico Pré-Natal
14.
Med Phys ; 39(8): 5060-4, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22894431

RESUMO

PURPOSE: Recently, greater attention has been paid to interactions between biomolecules particularly at the single-molecular level. Due to their novel properties, integrated lab-on-a-chip (LOC) devices and fluorescence correlation spectroscopy (FCS) are in high demand. METHODS: The LOC was manufactured using the technique of proton beam writing. The biomolecule fluorescein was used to probe flow profiles in the micro∕nanochannels on the LOC by FCS. The FCS optical system was based on a confocal microscopy setup. At different locations on the LOC, the numbers and traveling time of the fluorescein fluidic solution were investigated. RESULTS: From calibrations, ω(0) and τ(D) were 217 nm and 2.2 × 10(-5) s, respectively. Particle number and duration in passing through the detect volume, τ(F), were investigated. Results indicated that particle number was proportional to the size of micro∕nanochannels in the LOC. The particle number distribution and speed of the flow were mirror-symmetric in the two parallel (inlet∕outlet) microchannels. The distribution of the fluidic particles remained stable and the speed of the flow was nearly symmetrical when being transferred in the nanochannels. CONCLUSIONS: The results were realistic and in line with the hydromechanics, indicating that in multidisciplinary areas measurements of flow profiles by FCS are possible inside the LOC channels. This study paves the way to investigate biomolecular interactions at the single-molecular level.


Assuntos
Técnicas Analíticas Microfluídicas/métodos , Espectrometria de Fluorescência/métodos , Algoritmos , Calibragem , DNA/química , Difusão , Desenho de Equipamento , Fluoresceína/química , Humanos , Microscopia Confocal/métodos , Modelos Estatísticos , Óptica e Fotônica , Proteínas/química , Prótons , Reprodutibilidade dos Testes
15.
J Mater Chem B ; 9(9): 2314-2322, 2021 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-33616590

RESUMO

Nano-radiosensitizers provide a powerful tool for cancer radiation therapy. However, their limited tumor retention/penetration and the inherent or adaptive radiation resistance of tumor cells hamper the clinical success of radiation therapy. Herein, we report a synergistic strategy for potentiated cancer radiation/gene therapy based on transformable gold nanocluster aggregates loaded with antisense oligonucleotide-targeting survivin mRNA (named AuNC-ASON). AuNC-ASON exhibited acidic pH-triggered structure splitting from a gold nanocluster aggregate (around 80 nm) to gold nanocluster (<2 nm), leading to the tumor microenvironment-responsive size transformation of the nano-radiosensitizer and activated release of the loaded antisense oligonucleotides to perform gene silencing. The in vitro experiments demonstrated that AuNC-ASON could amplify and improve the radio-sensitivity of tumor cells (the sensitization enhancement ratio was about 1.81) as a result of the synergistic effect of the transformable gold nanocluster radiosensitizer and survivin gene interference. Remarkably, the size transformation capability realized the high tumor retention/penetration and renal metabolism of AuNC-ASON in vivo and boosted the radio-susceptibility of cancer cells with the assistance of survivin gene interference, synergistically achieving potentiated tumor radiation/gene therapy. The proposed concept of transformable nano-radiosensitizer aggregate-based synergistic therapy can be utilized as a general strategy to guide the design of activatable multifunctional nanosystems for cancer theranostics.


Assuntos
Portadores de Fármacos/química , Terapia Genética , Ouro/química , Nanoestruturas/química , Neoplasias/genética , Neoplasias/radioterapia , Linhagem Celular Tumoral , Terapia Combinada , Liberação Controlada de Fármacos , Inativação Gênica , Humanos , Concentração de Íons de Hidrogênio , Oligonucleotídeos Antissenso/química , Oligonucleotídeos Antissenso/genética , Radiossensibilizantes/química , Radiossensibilizantes/farmacologia , Radiossensibilizantes/uso terapêutico
16.
Front Oncol ; 11: 752651, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34900700

RESUMO

Breast cancer is the second cause of cancer-associated death among women and seriously endangers women's health. Therefore, early identification of breast cancer would be beneficial to women's health. At present, circular RNA (circRNA) not only exists in the extracellular vesicles (EVs) in plasma, but also presents distinct patterns under different physiological and pathological conditions. Therefore, we assume that circRNA could be used for early diagnosis of breast cancer. Here, we developed classifiers for breast cancer diagnosis that relied on 259 samples, including 144 breast cancer patients and 115 controls. In the discovery stage, we compared the genome-wide long RNA profiles of EVs in patients with breast cancer (n=14) and benign breast (n=6). To further verify its potential in early diagnosis of breast cancer, we prospectively collected plasma samples from 259 individuals before treatment, including 144 breast cancer patients and 115 controls. Finally, we developed and verified the predictive classifies based on their circRNA expression profiles of plasma EVs by using multiple machine learning models. By comparing their circRNA profiles, we found 439 circRNAs with significantly different levels between cancer patients and controls. Considering the cost and practicability of the test, we selected 20 candidate circRNAs with elevated levels and detected their levels by quantitative real-time polymerase chain reaction. In the training cohort, we found that BCExoC, a nine-circRNA combined classifier with SVM model, achieved the largest AUC of 0.83 [95% CI 0.77-0.88]. In the validation cohort, the predictive efficacy of the classifier achieved 0.80 [0.71-0.89]. Our work reveals the application prospect of circRNAs in plasma EVs as non-invasive liquid biopsies in the diagnosis and management of breast cancer.

17.
Anal Chim Acta ; 1093: 106-114, 2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-31735203

RESUMO

Single nucleotide polymorphism (SNP) was associated with many human diseases, therefore, SNP detection was important for early diagnosis and clinical prognosis. Herein, a simple and accurate method for visual detection SNP sites (A/A, G/G, A/G) in CYP1A1 gene related to cancers based on colloidal gold nucleic acid strip biosensor and primer-specific polymerase chain reaction (PCR) was established. This method could directly distinguish SNP sites on strip biosensor by introducing twice PCR amplifications. The second PCR (primer-specific PCR) was performed using specific product of the first PCR as template, thus this twice PCR could reduce non-specific amplification greatly and obtain target product. In addition, single-strand or double-strand DNA (ssDNA or dsDNA) was accurately produced by introducing mismatched base at the 3' end of forward primers in primer-specific PCR. The designed strip biosensor could only combine with the ssDNA, thus visual detection of SNP could be achieved within 10 min by color difference of a pair of strips. 61 human blood samples by this method were identical with those of pyrosequencing. This method had the advantages of rapid, visual and low-cost and was expected to be applied in medical diagnosis.


Assuntos
Técnicas Biossensoriais/métodos , Citocromo P-450 CYP1A1/genética , DNA/sangue , Coloide de Ouro/química , Polimorfismo de Nucleotídeo Único , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/genética , Colorimetria/métodos , DNA/genética , Sondas de DNA/química , Ouro/química , Humanos , Nanopartículas Metálicas/química , Reação em Cadeia da Polimerase/métodos
18.
Database (Oxford) ; 20202020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-32047888

RESUMO

RNA-binding proteins (RBPs) play important roles in regulating the expression of genes involved in human physiological and pathological processes, especially in cancers. Many RBPs have been found to be dysregulated in cancers; however, there was no tool to incorporate high-throughput data from different dimensions to systematically identify cancer-related RBPs and to explore their causes of abnormality and their potential functions. Therefore, we developed a database named RBPTD to identify cancer-related RBPs in humans and systematically explore their functions and abnormalities by integrating different types of data, including gene expression profiles, prognosis data and DNA copy number variation (CNV), among 28 cancers. We found a total of 454 significantly differentially expressed RBPs, 1970 RBPs with significant prognostic value, and 53 dysregulated RBPs correlated with CNV abnormality. Functions of 26 cancer-related RBPs were explored by analysing high-throughput RNA sequencing data obtained by crosslinking immunoprecipitation, and the remaining RBP functions were predicted by calculating their correlation coefficient with other genes. Finally, we developed the RBPTD for users to explore functions and abnormalities of cancer-related RBPs to improve our understanding of their roles in tumorigenesis. Database URL: http: //www.rbptd.com.


Assuntos
Bases de Dados de Proteínas , Neoplasias , Proteínas de Ligação a RNA , Software , Sistemas de Gerenciamento de Base de Dados , Humanos , Neoplasias/genética , Neoplasias/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo
19.
ACS Appl Mater Interfaces ; 12(36): 40052-40066, 2020 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-32806885

RESUMO

Ameliorated therapy based on the tumor microenvironment is becoming increasingly popular, yet only a few methods have achieved wide recognition. Herein, targeting multifunctional hydrophilic nanomicelles, AgBiS2@DSPE-PEG2000-FA (ABS-FA), were obtained and employed for tumor treatment. In a cascade amplification mode, ABS-FA exhibited favorable properties of actively enhancing computed tomography/infrared (CT/IR) imaging and gently relieving ambient oxygen concentration by cooperative photothermal and sonodynamic therapy. Compared with traditional Bi2S3 nanoparticles, the CT imaging capability of the probe was augmented (43.21%), and the photothermal conversion efficiency was increased (33.1%). Furthermore, remarkable ultrasonic dynamic features of ABS-FA were observed, with increased generation of reactive oxygen species (24.3%) being obtained compared to Ce6, a commonly used sonosensitizer. Furthermore, ABS-FA exhibited obvious inhibitory effects on HeLa cell migration at 6 µg/mL, which to some extent, demonstrated its suppressive effect on tumor growth. A lower dose, laser and ultrasonic power, and shorter processing time endowed ABS-FA with excellent photothermal and sonodynamic effects. By mild cascade mode, the hypoxic condition of the tumor site was largely improved, and a suitable oxygen-rich environment was provided, thereby endowing ABS-FA with a superior synergistically enhanced treatment effect compared with the single-mode approach, which ultimately realized the purpose of "one injection, multiple treatment". Moreover, our data showed that ABS-FA was given with a biological safety profile while harnessing in vivo. Taken together, as a synergistically enhanced medical diagnosis and treatment method, the one-for-all nanoplatform will pave a new avenue for further clinical applications.


Assuntos
Antineoplásicos/farmacologia , Ácido Fólico/farmacologia , Neoplasias Experimentais/terapia , Terapia Fototérmica , Compostos de Prata/farmacologia , Sulfetos/farmacologia , Terapia por Ultrassom , Animais , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Ácido Fólico/química , Células HeLa , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias Experimentais/patologia , Tamanho da Partícula , Compostos de Prata/química , Sulfetos/química , Propriedades de Superfície
20.
Theranostics ; 9(25): 7666-7679, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31695793

RESUMO

Despite burgeoning development of nanoplatform made in the past few years, it remains a challenge to produce drug nanocarrier that enables requested on/off drug release. Thus, this study aimed to develop an ideal near-infrared light-triggered smart nanocarrier for targeted imaging-guided treatment of cancer that tactfully integrated photothermal therapy with chemotherapy to accurately control drug release time and dosage. Methods: This delivery system was composed of Ag2S QD coating with dendritic mesoporous silica (DMSN), which acted as nanocarrier of doxorubicin localized inside pores. To provide the nanocarrier with controlled release capability, a polypeptide-engineered that structure was reversible to photothermal effect of Ag2S QD, was covalently grafted to the external surface of drug-loaded DMSN. Results: This nanocarrier with the size of 40~60 nm had satisfactory biocompatibility and photothermal conversion efficiency up to 28.35%. Due to acidity-triggered charge reversal of polypeptide, which significantly extended circulation time and improved targeting ability, fluorescence and photoacoustic signals were still obvious at tumor site post-24 h by tail vein injection and chemo-photothermal synergistic therapy obviously enhanced antitumor efficacy. Mild PTT with multiple short-term exposures not only reduced the side effect of overdose drug but also avoided skin damage caused by long-term irradiation. Conclusion: By adjusting irradiation time and on/off cycle, multiple small amount local drug release reduced the side effect of overdose drug and skin damage. This novel approach provided an ideal near-infrared light-triggered nanocarrier with accurate control of area, time, and especially dosage.


Assuntos
Portadores de Fármacos/química , Nanopartículas/química , Peptídeos/química , Animais , Linhagem Celular Tumoral , Terapia Combinada/métodos , Doxorrubicina/química , Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos/efeitos dos fármacos , Fluorescência , Células HeLa , Humanos , Raios Infravermelhos , Células MCF-7 , Camundongos , Camundongos Nus , Neoplasias/tratamento farmacológico , Neoplasias/terapia , Técnicas Fotoacústicas/métodos , Fototerapia/métodos , Dióxido de Silício/química
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