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1.
Anal Chem ; 92(19): 13118-13125, 2020 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-32841018

RESUMO

As an important biomarker for early diagnosis of cancers, sensitive detection and high-resolution imaging of microRNA-21 in cancer cells have become important and challengeable. In this work, highly sensitive detection and spatial imaging of intracellular microRNA-21 were realized by the reduced signal background through vertical polarization excitation with a polarizer. The lateral local surface plasmon resonance property of gold nanorods (AuNRs) displayed a pronounced green color with low scattering intensity, which was adjusted to red color with strong scattering intensity when the core-satellite gold nanoparticle (AuNP) assembly was constructed on the side of AuNRs through a catalyzed hairpin assembly (CHA) circuit in the presence of microRNA-21. This unique approach allows for effectively reducing the strong background signal to improve the sensitivity of detection. Additionally, the proposed strategy can not only realize the sensitive detection of microRNA-21 with the limit of detection as low as 2 pM (3σ) but also achieve the high spatial imaging of cancer cells, which provided a specific strategy for the construction and imaging of intracellular imaging probes. It is believed that the simple and sensitive approach on the basis of lateral local surface plasmon resonance property of anisotropic AuNRs with excellent sensitivity combined with high spatial imaging holds promising potentials to visualize intracellular microRNAs with low abundance.


Assuntos
Técnicas Biossensoriais , Ouro/química , Nanopartículas Metálicas/química , MicroRNAs/análise , Imagem Óptica , Ressonância de Plasmônio de Superfície , Anisotropia , Células Cultivadas , Células Hep G2 , Humanos
2.
Biosens Bioelectron ; 202: 114001, 2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35078141

RESUMO

As the common hepatitis viruses, hepatitis B virus (HBV) and hepatitis C virus (HCV) are important causes of liver diseases, which greatly threaten human health and public hygiene. Furthermore, due to the similar transmission routes of HBV and HCV, it is highly susceptible to suffer from the cross-infection of HBV and HCV when humans are infected by hepatitis viruses. So it is urgent to develop strategies with high sensitivity to distinguish HBV/HCV and detect their overlapping infection. Herein, a new biosensor named "hepatitis virus indicator" for simultaneous detection of HBV and HCV based on the automatic particle enumeration was developed by the combination of Exo III assisted signal amplification strategy and particle counting technology with a dark-field microscopy. The limit of detections (LOD) were as low as 0.194 pM for HBV and 0.169 pM for HCV, respectively. In addition, the proposed method was capable of simultaneously detecting HBV and HCV based on the colorful light scattering from plasmonic nanoparticles. The proposed assay was simple, sensitive and selective for the simultaneous detection of HBV and HCV, which provided a new idea for the early diagnosis of diseases, such as hepatitis A virus (HAV), hepatitis D virus (HDV) and hepatitis E virus (HEV).


Assuntos
Técnicas Biossensoriais , Hepatite B , Hepatite C , Hepatite Viral Humana , Hepacivirus , Hepatite B/diagnóstico , Vírus da Hepatite B , Hepatite C/diagnóstico , Vírus de Hepatite , Hepatite Viral Humana/diagnóstico , Humanos
3.
Org Biomol Chem ; 9(20): 6917-9, 2011 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-21879136

RESUMO

One multifunctional small molecule can undergo a natural condensation reaction under the control of reducing agent to generate amphiphilic oligomers which quickly self-assemble supramolecular nanoparticles or form crosslinked, reversibly degradable polymers.

4.
ACS Appl Bio Mater ; 4(4): 3469-3475, 2021 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-35014431

RESUMO

MicroRNAs, as one kind of significant biomarkers, play indispensable roles in the diagnosis and treatment of cancers. Yet, owing to low expression and high sequence homology, high sensitivity and specificity for microRNA detection are greatly challenging. Herein, a sensitive sensing platform with high specificity was developed for microRNA-27a (miRNA-27a) based on the miRNA-27a-triggered chemical etching of gold nanorods to a smaller size, which was accompanied by a significant blue shift and a large decrease of intensity in the localized surface plasmon resonance (LSPR) scattering and remarkable color variability from red to green. When combined with strand displacement reactions as well as liposome signal amplification and transduction, the proposed bioassay presented high selectivity toward miRNA-27a in a dynamic range from 100 fM to 3 pM and a low limit of detection of 16.5 fM (3σ/k) by dark-field microscopy. Additionally, the remarkable discrimination of single nucleotide difference suggested superior selectivity and was able to detect miRNA-27a extracted from breast cancer cells. The strategy put forward is universal, presenting amusing application prospects in the early diagnosis of various cancers by adapting the corresponding nucleotide sequences.


Assuntos
Materiais Biocompatíveis/química , Neoplasias da Mama/diagnóstico , Ouro/química , MicroRNAs/análise , Nanotubos/química , Ressonância de Plasmônio de Superfície , Neoplasias da Mama/metabolismo , Humanos , Teste de Materiais , MicroRNAs/metabolismo , Tamanho da Partícula
5.
J Ethnopharmacol ; 101(1-3): 324-9, 2005 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-16099120

RESUMO

This research aims to study the metabolism and pharmacokinetics of phytoestrogen kobophenol A (1), the main active compound of Caragana sinica (Buc'hoz) Rehd. (Fabaceae), in rats. Metabolites of 1 in rats' feces were isolated and purified by multi-chromatograph techniques; three new metabolites of 1, named koboquinone A (M1), koboquinone B (M2) and koboquinone C (M3), were isolated, purified from rats' feces after they being orally administered with 1. Structure identification of the metabolites was fulfilled by spectroscopic analysis. M1 and M2 are structurally different to those natural occurring stilbene tetramers, which also have para-quinone structure. M1 also showed the activity of stimulating the proliferation of cultured osteoblasts. The pharmacokinetics of 1 in rats could be described by a two-compartmental model (P<0.05). The half-life was 0.68 h for i.v. administration and 5.78 h for oral administration. The oral bioavailability of 1 was calculated to be 2.0%; rats tissue distribution experiments show that 1 was prominently concentrated in livers. Both of the low oral bioavailability and the rapid reduction of 1 in blood indicated a suitable formulation is needed while it is developed as a new drug.


Assuntos
Caragana/química , Fitoestrógenos/farmacocinética , Estilbenos/farmacocinética , Animais , Masculino , Ratos , Ratos Sprague-Dawley , Distribuição Tecidual
6.
Sci Rep ; 3: 1024, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23289066

RESUMO

Herein we developed a new "smart" Gd-based MR contrast agent (i.e., 1) which is susceptive to furin, a protease overexpressed in tumor. Under the action of furin, 1 condenses to form dimers (1-Ds) and the latter self-assemble into gadolinium nanparticles (Gd-NPs). Relaxivity of 1-D is more than 2 folds of those of 1 and magnevist at 1.5 T, and 1.4 folds of that of 1 at 3 T. Intracellular condensation of 1 in furin-overexpressed MDA-MB-468 cells was proven with direct two-photon laser microscopy (TPLM) fluorescence imaging of the cells incubated with the europium analog of 1 (i.e., 2). Intracellular Gd-NPs of 1 were uncovered and characterized for the first time. MRI of MDA-MB-468 tumors showed that 1 has enhanced MR contrast within the tumors than that of its scrambled control 1-Scr.


Assuntos
Meios de Contraste/química , Gadolínio/química , Nanopartículas Metálicas/química , Animais , Linhagem Celular Tumoral , Meios de Contraste/síntese química , Dimerização , Európio/química , Furina/metabolismo , Humanos , Imageamento por Ressonância Magnética , Nanopartículas Metálicas/ultraestrutura , Camundongos , Camundongos Nus , Microscopia Confocal , Neoplasias/diagnóstico por imagem , Radiografia , Transplante Heterólogo
7.
Sci Rep ; 3: 1848, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23673405

RESUMO

Herein, we report the rational design of a DEVD-based heptapeptide hydrogelator 1 which is susceptible to caspase-3 (CASP3), and its isomeric control hydrogelator 2 with a DEDV-based heptapeptide sequence. Self-assembly of 1 in water results in flexuous, long nanofibers to form supramolecular hydrogel I with higher mechanical strength than that of hydrogel II which is composed of rigid, short nanofibers of 2. In vitro enzymatic analysis indicated that 1 is susceptive to CASP3 while 2 is not. 3-(4,5-dimethylthiazol-2-yl) 2,5 diphenyl tetrazolium bromide (MTT) and Western blot analyses indicated that DEDV-based hydrogelator 2 induces cell death via apoptotic pathway while the DEVD-based hydrogelator 1 minimizes cellular apoptosis induction.


Assuntos
Apoptose/efeitos dos fármacos , Carcinoma Hepatocelular/patologia , Caspase 3/metabolismo , Proliferação de Células/efeitos dos fármacos , Hidrogéis/farmacologia , Neoplasias Hepáticas/patologia , Fragmentos de Peptídeos/farmacologia , Western Blotting , Carcinoma Hepatocelular/tratamento farmacológico , Caspase 3/química , Células HeLa , Humanos , Hidrogéis/química , Neoplasias Hepáticas/tratamento farmacológico , Nanofibras/química , Oligopeptídeos/farmacologia , Fragmentos de Peptídeos/química , Células Tumorais Cultivadas
8.
Chem Commun (Camb) ; 47(37): 10320-2, 2011 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-21853204

RESUMO

A caspase-3 controlled condensation was applied to self-assemble biotinylated nanoparticles for capturing FITC-labelled streptavidin and subsequently turning on the fluorescence signal.


Assuntos
Caspase 3/metabolismo , Nanopartículas/química , Biotinilação , Fluoresceína-5-Isotiocianato/química , Corantes Fluorescentes/química , Proteínas Imobilizadas/química , Proteínas Imobilizadas/metabolismo , Espectrometria de Fluorescência , Estreptavidina/química , Estreptavidina/metabolismo
9.
Chem Pharm Bull (Tokyo) ; 53(11): 1387-91, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16272718

RESUMO

Nineteen new derivatives of the naturally occurring compound, goniothalamin, were prepared by chemical modification and semi-synthetic methods. The antitumor activities of these derivatives and goniothalamin were evaluated in vitro against human tumor cell lines, and most of them showed an inhibitory effect against HL-60 cancer cells. The derivatives 10-nitro-goniothalamin and 10-amino-goniothalamin gave selective inhibition concentration (IC50) of 1.10 and 1.14 microg/ml, respectively, against human stomach cancer SGC-7901 cells, while that of etoposide (vp-16) as the positive control was 6.07 microg/ml. Finally, the partition coefficients, logP (pi values), of these derivative molecules, were evaluated by calculating the additive approximate organic fragment logP value.


Assuntos
Annonaceae/química , Antineoplásicos Fitogênicos/síntese química , Antineoplásicos Fitogênicos/farmacologia , Lactonas/síntese química , Lactonas/farmacologia , Estirenos/síntese química , Estirenos/farmacologia , Linhagem Celular Tumoral , Cromatografia em Camada Fina , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Indicadores e Reagentes , Espectroscopia de Ressonância Magnética , Folhas de Planta/química , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Espectrofotometria Ultravioleta
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