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1.
Cell Prolif ; 53(7): e12822, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32530560

RESUMO

Breast cancer has seriously been threatening physical and mental health of women in the world, and its morbidity and mortality also show clearly upward trend in China over time. Through inquiry, we find that survival rate of patients with early-stage breast cancer is significantly higher than those with middle- and late-stage breast cancer, hence, it is essential to conduct research to quickly diagnose breast cancer. Until now, many methods for diagnosing breast cancer have been developed, mainly based on imaging and molecular biotechnology examination. These methods have great contributions in screening and confirmation of breast cancer. In this review article, we introduce and elaborate the advances of these methods, and then conclude some gold standard diagnostic methods for certain breast cancer patients. We lastly discuss how to choose the most suitable diagnostic methods for breast cancer patients. In general, this article not only summarizes application and development of these diagnostic methods, but also provides the guidance for researchers who work on diagnosis of breast cancer.


Assuntos
Neoplasias da Mama/diagnóstico , Detecção Precoce de Câncer/métodos , Feminino , Humanos , Programas de Rastreamento/métodos
2.
J Biomed Nanotechnol ; 14(1): 20-43, 2018 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-29463364

RESUMO

Materials derived from biological sources not only offer biocompatibility but also adjust with the disease for elongated treatments and more effective therapies. These materials can be utilized as building blocks to construct state of the art drug delivery vehicles like nanoparticles, hydrogels, and nanofibers capable of dramatically enhancing the therapeutic efficiency in cancer treatment. New emerging trends in drug delivery design are constantly reported in recent literature using carbohydrates like cellulose, chitosan, and alginate and proteins like albumin, collagen, gelatin, and zein. In addition, drug vehicles with combination of carbohydrates and proteins have proved extremely effective. This article reviews carbohydrate and protein-based materials in fabrication of cutting edge drug delivery systems and clarifies their future impact in therapeutic methods to cure cancer.


Assuntos
Carboidratos , Sistemas de Liberação de Medicamentos , Nanopartículas , Proteínas , Quitosana
3.
J Nanosci Nanotechnol ; 15(7): 4815-28, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26373042

RESUMO

China is one of the countries with the highest incidence of gastric cancer, and accounts for over 40% of all new gastric cancer cases in the world. Genetic factors as well as environmental factors play a role in development of gastric cancer. To investigate the independent roles of single nucleotide polymorphisms (SNPs) in base excision repair (BER) genes (APE1 and NEIL2), carcinogen metabolism gene (CYP2E1) and tumor suppressor pathway gene (MDM2) for gastric cancer susceptibility in a Chinese population, we conducted a hospital based case-control study to evaluate the potential association between these polymorphisms and susceptibility to gastric cancer in a Northern Jiangsu population. We also associated the NEIL-2 mRNA expression with the studied NEIL2 SNP genotypes to assess whether the genotypes have influence on the NEIL2 mRNA (hence protein) expression. Five SNPs, APE 1 (rs2275008), NEIL 2 (rs804270), MDM2 (rs2279744), and CYP 2E1 (rs2480256 and rs2031920), were genotyped by TaqMan assays in 105 gastric cancer cases and 118 controls. Genotype frequency distribution showed that the APE 1 SNP (rs2275008), NEIL 2 SNP (rs804270), MDM2 SNP (rs2279744), and CYP 2E1 SNP (rs2031920) had more mutant alleles in gastric cancer cases than controls (76.19, 68.57, 54.29, and 43.81%, respectively), while CYP 2E1 SNP (rs2480256) had large percentage of both alleles (43.81%). Risk analysis revealed that there was increased risk for gastric cancer in subjects with mutant alleles in APE 1 (rs2275008: OR 5.49, 95% CI = 2.6-5.7, p <.0001), NEIL 2 (rs804270: OR 2.3, 95% CI = 1.22-4.3, p=0.01), MDM2 (rs2279744: OR 14.65, 95% CI = 5.63-8.15, p < .0001), and CYP 2E1 (rs2031920: OR 8.385, 95% CI = 3.2-5.3, p < .0001) SNPs. Moreover, the NEIL2 mRNA expression analysis showed that there was significant differential expression of NEIL2 mRNA among the randomly tested NEIL2 genotypes (p = 0.005), with low expression seen in variant genotypes than in other genotypes. In conclusion, variant alleles in the NEIL2 (rs804270), APE1 (rs2275008), CYP2E1 (rs2031920) and MDM2 (rs2279744) SNPs may independently influence susceptibility to gastric cancer in a Northern Jiangsu Chinese population. The genotypes may also independently influence their respective gene mRNA expression, as seen in our study, where there was differential expression of the NEIL2 mRNA among the genotypes, with low NEIL2 mRNA expression seen in the variant genotype.


Assuntos
Citocromo P-450 CYP2E1/genética , DNA Glicosilases/genética , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/genética , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único , Proteínas Proto-Oncogênicas c-mdm2/genética , Neoplasias Gástricas/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Povo Asiático , Estudos de Casos e Controles , China/epidemiologia , Citocromo P-450 CYP2E1/biossíntese , DNA Glicosilases/biossíntese , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/biossíntese , Feminino , Regulação da Expressão Gênica , Frequência do Gene , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas Proto-Oncogênicas c-mdm2/biossíntese , Neoplasias Gástricas/epidemiologia , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia
4.
J Nanosci Nanotechnol ; 15(2): 1123-9, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26353621

RESUMO

In this research, a novel method for relative fluorescent quantification of DNA based on Fe3O4@SiO2@Au gold-coated magnetic nanocomposites (GMNPs) and multiplex ligation- dependent probe amplification (MLPA) has been developed. With the help of self-assembly, seed-mediated growth and chemical reduction method, core-shell Fe3O4@SiO2@Au GMNPs were synthesized. Through modified streptavidin on the GMNPs surface, we obtained a bead chip which can capture the biotinylated probes. Then we designed MLPA probes which were tagged with biotin or Cy3 and target DNA on the basis of human APP gene sequence. The products from the thermostable DNA ligase induced ligation reactions and PCR amplifications were incubated with SA-GMNPs. After washing, magnetic separation, spotting, the fluorescent scanning results showed our method can be used for the relative quantitative analysis of the target DNA in the concentration range of 03004~0.5 µM.


Assuntos
DNA/análise , DNA/genética , Nanopartículas Metálicas/química , Microscopia de Fluorescência/instrumentação , Reação em Cadeia da Polimerase Multiplex/instrumentação , Nanocompostos/ultraestrutura , Sequência de Bases , Técnicas Biossensoriais/instrumentação , Técnicas Biossensoriais/métodos , Desenho de Equipamento , Análise de Falha de Equipamento , Ouro/química , Nanopartículas Metálicas/ultraestrutura , Microscopia de Fluorescência/métodos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase Multiplex/métodos , Nanocompostos/química , Análise de Sequência de DNA/instrumentação , Análise de Sequência de DNA/métodos , Dióxido de Silício/química
5.
Theranostics ; 5(1): 71-85, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25553099

RESUMO

A novel system for copy number variation (CNV) analysis was developed in the present study using a combination of magnetic separation and chemiluminescence (CL) detection technique. The amino-modified probes were firstly immobilized onto carboxylated magnetic nanoparticles (MNPs) and then hybridized with biotin-dUTP products, followed by amplification with ligation-dependent polymerase chain reaction (PCR). After streptavidin-modified alkaline phosphatase (STV-AP) bonding and magnetic separation, the CL signals were then detected. Results showed that the quantification of PCR products could be reflected by CL signal values. Under optimum conditions, the CL system was characterized for quantitative analysis and the CL intensity exhibited a linear correlation with logarithm of the target concentration. To validate the methodology, copy numbers of six genes from the human genome were detected. To compare the detection accuracy, multiplex ligation-dependent probe amplification (MLPA) and MNPs-CL detection were performed. Overall, there were two discrepancies by MLPA analysis, while only one by MNPs-CL detection. This research demonstrated that the novel MNPs-CL system is a useful analytical tool which shows simple, sensitive, and specific characters which are suitable for CNV analysis. Moreover, this system should be improved further and its application in the genome variation detection of various diseases is currently under further investigation.


Assuntos
Dosagem de Genes , Separação Imunomagnética , Reação em Cadeia da Ligase/métodos , Luminescência , Nanopartículas , Feminino , Humanos , Masculino
6.
J Nanosci Nanotechnol ; 14(5): 3348-55, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24734551

RESUMO

A novel and simple emulsifier-free emulsion polymerization technique was developed for preparation of mono-dispersed amino functionalized polymer microspheres with well defined diameters (about 400 nm). Various characterization methods demonstrated that the obtained amino microspheres had a uniform size and good dispersity which were confirmed by scanning electron microscope (SEM). Zeta potential and Fourier transform infrared spectrometer (FT-IR) demonstrated that amino groups have been successfully introduced to the microsphere surface. These functionalized microspheres have been shown to be efficient and controllable carriers capable of immobilizing and enriching monoclonal antibodies. Moreover, a newest chemiluminescent enzyme-linked immunoassay (ELISA) approach has been developed for human Hepatitis B virus surface antigen (HBsAg) detection. HBsAg was sandwiched between goat anti-HBsAg polyclonal antibody and mouse anti-HBsAg antibody. Alkaline phosphatase (ALP) conjugated horse anti-mouse immunnogloblin was used to bond with monoclonal antibody. Finally, chemiluminesent (CL) signals were recorded after adding 3-(2-spiroadamantane)-4-methoxy-4-(3-phosphoryloxy) phenyl-1,2-dioxetane (AMPPD) which was used as a chemiluminescent substrate reagent of ALP. This novel chemiluminescent ELISA assay was proved to be of excellent specificity and high sensitivity when using ALP and AMPPD luminescence systems for specific HBsAg detection.


Assuntos
Antígenos de Superfície da Hepatite B/análise , Microesferas , Ensaio de Imunoadsorção Enzimática , Humanos , Limite de Detecção , Microscopia Eletrônica de Varredura , Nanopartículas , Espectroscopia de Infravermelho com Transformada de Fourier
7.
J Nanosci Nanotechnol ; 14(1): 932-45, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24730310

RESUMO

New and emerging technologies, such as nanotechnology, have the potential to advance nutrition science by assisting in the discovery, development, and delivery of several intervention strategies to improve health and reduce the risk and complications of several diseases, including gastric cancer. This article reviews gastric cancer in relation to nutrition, discussing gastric carcinogenesis in-depth in relation to prevention of the disease by nutrition, as well as current detection approaches using nanotechnology. The current status of molecular nutritional biomarkers for gastric cancer is also discussed, as well as future strategies for the tailored management of gastric cancer.


Assuntos
Dietoterapia/métodos , Análise de Alimentos/métodos , Imagem Molecular/métodos , Nanopartículas/uso terapêutico , Neoplasias Gástricas/dietoterapia , Neoplasias Gástricas/diagnóstico , Humanos , Nanotecnologia/métodos
8.
J Nanosci Nanotechnol ; 13(5): 3204-13, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23858832

RESUMO

Magnetic nanoparticles (MNPs), especially superparamagnetic iron oxide nanoparticles (SPIONs), have long been studied as contrast agents for magnetic resonance imaging (MRI). Owing to recent progress in synthesis and surface modification, many new avenues have opened for this class of biomaterials. Such nanoparticles are not merely tiny magnetic crystals, but potential platforms with large surface-to-volume ratios. By taking advantage of the well developed surface chemistry of MNPs, a wide range of functionalities, such as targeting, imaging, detection and therapeutic features, can be loaded onto their surfaces. This property makes magnetic nanoparticles excellent biomaterials for molecular detection of infectious agents and cancer. This short review thus discusses current advances on magnetic nanoparticles as molecular detection agents for infectious agents and cancer.


Assuntos
Doenças Transmissíveis/diagnóstico , Nanopartículas de Magnetita/química , Imagem Molecular/métodos , Neoplasias/diagnóstico , Animais , Humanos
9.
J Nanosci Nanotechnol ; 13(8): 5859-63, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23882849

RESUMO

In this study, we present the synthesis of ZnO nanowire by hydrothermal process through reutilization of sludge from soy sauce wastewater electrochemical treatment. The influences of floc content and caramel pigment concentration on the morphologies of ZnO were studied. The products were characterized by XRD and SEM. The results showed that ZnO powder was of hexagonal wurtzite structure and well crystallized with high purity. Floc content and caramel pigment concentration played an important role in the final morphologies of ZnO nanowires. On the basis of these results, a possible growth mechanism for the formation of ZnO nanowires was described. These findings not only may contribute to control the synthesis of ZnO, but also present a novel method for the disposal of wastewater treatment sludge.


Assuntos
Nanofios/química , Esgotos/química , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química , Óxido de Zinco/química , Técnicas Eletroquímicas , Floculação , Alimentos de Soja
10.
J Biomed Nanotechnol ; 8(6): 938-43, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23030002

RESUMO

With the wide application of nanomaterials in biomedical detection in recent years, hybridization methods which use nanoparticles as solid phase hybridization carriers have emerged. However, commercial equipments, such as conventional thermal cyclers and hybridization ovens are usually not appropriate for DNA hybridization on the surface of nanoparticles. We designed and improved a total temperature micro-volume blended incubating and hybridizing apparatus (TTMHA), which can be used for blending and suspending of nanoparticles in a small volume and liquid phase environment. This device highlights the mechanical rotation structure which can not only provide a uniform temperature field, but also makes the liquid flow fully in the reaction system and improves DNA hybridization efficiency significantly. A complex PID control algorithm, including Bang-Bang control and Fuzzy-PID control algorithm, was applied in this research project to improve the control accuracy and stability. Furthermore, a model detection experiment using ssDNA (single strand DNA) sequence was conducted in thermal cyclers and TTMHA respectively to verify the optimal hybridization efficiency of the TTMHA.


Assuntos
DNA/genética , Nanopartículas/química , Nanotecnologia/métodos , Hibridização de Ácido Nucleico , Algoritmos , Sequência de Bases , DNA de Cadeia Simples/genética , Desenho de Equipamento , Lógica Fuzzy , Humanos , Dados de Sequência Molecular , Nanomedicina/métodos , Oligonucleotídeos/genética , Reprodutibilidade dos Testes , Temperatura , Fatores de Tempo
11.
J Nanosci Nanotechnol ; 12(3): 2028-36, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22755016

RESUMO

ZnO microstructures with various morphologies have been controllably synthesized by hydrothermal route using different precipitant and zinc source in liquid solution. X-ray diffraction (XRD) and scanning electron microscopy (SEM) were used to characterize the ZnO2, Zn(OH)2 and ZnO structures to understand the role of precipitant and precursors in the growth of various morphologies. The nucleation and growth process can regulate by changing the precipitant. When H2O2 was used as precipitant, ZnO particles with a rather uniform particle size of -500 nm and a rather rough surface was obtained. While, ZnO synthesized in this polyvinyl pyrrolidone (PVP) solution has the same granular morphology with particle size of 300-1000 nm. In contrast, ZnO sunflower and polyhedron aggregates composed of several smaller polyhedron were formed, when ammonium hydroxide and NH4HCO3 was applied, respectively. Meanwhile, precursors play an important role in the determination of the morphology of ZnO. Sunflower and dumbbell like ZnO composed of nanosheets were obtained, when different centrifugal component of Zn(OH)2 suspension was applied as zinc source. In contrast, sunflower and dumbbell like ZnO composed of nanorods and ZnO rods were obtained, when different centrifugal components of ZnO2 suspension were used as zinc sources. The growth mechanism of ZnO nanostructures fabricated by the hydrothermal process using different zinc sources was tentatively investigated.


Assuntos
Óxido de Zinco/síntese química , Microscopia Eletrônica de Varredura , Difração de Raios X
12.
J Nanosci Nanotechnol ; 12(3): 2858-65, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22755135

RESUMO

Solid-state NMR has the potential to contribute to the quality of monitoring of the in growth of synthetic biomaterials in bone related tissue engineering. Severe experimental difficulties arise from the morphological diversity of bone, from the coexistence, interrelationship and great complexity of its organic and inorganic components, and lastly, from the substantial sensitivity of bone samples to physical and chemical effects. High-resolution solid-state NMR gives us the opportunity to look specifically at selected magnetic nuclei in whole bone without any chemical pretreatment, thus avoiding interference with bone structure. Solid-state NMR spectroscopy is thus an excellent tool to obtain such high-resolution information on bone samples not subjected to any chemical pretreatment. This short review has thus discussed current application of solid-state NMR in characterization of bone related tissue engineering.


Assuntos
Osso e Ossos , Espectroscopia de Ressonância Magnética/métodos , Engenharia Tecidual , Próteses e Implantes , Medicina Regenerativa
13.
J Nanosci Nanotechnol ; 12(1): 267-73, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22523975

RESUMO

We present a systematic study on the preparation, characteration and potential application of Fe3O4 and Fe3O4@SiO2 nanoparticles. Fe3O4 nanoparticles of controllable diameters were successfully synthesized by solvothermal system with tuning pH. The magnetic properties of nanoparticles were measured by vibration sample magnetometer. Fe3O4@ SiO2 nanoparticles were obtained via classic Stöber process. Streptavidin coated Fe3O4@SiO2 nanoparticles were prepared by covalent interaction. The quantity of streptavidin bound to nanoparticles was determined by UV-Vis spectrometer. To evaluate the binding efficiency and capacity of nucleic acid on nanoparticles, the capture of biotinylated oligonucleotide on streptavidin coated Fe3O4@SiO2 nanoparticles at different concentration was estimated by fluorescence detection. Both Fe3O4 and Fe3O4@SiO2 nanoparticles exhibited well crystallization and magnetic properties. The maximal amount of streptavidin immobilized onto the Fe3O4@SiO2 nanoparticles was 29.3 microg/mg. The saturation ratio of biotinylated oligonucleotides captured on streptavidin coated Fe3O4@SiO2 nanoparticles was 5 microM/mg within 20 minutes, indicating that FeO4@SiO2 nanoparticles immobilized by streptavidin were excellent carriers in nucleic acid analysis due to their convenient magnetic-separation property. Therefore, the synthesized Fe3O4 and Fe3O4@SiO2 nanoparticles with controllable size and high magnetic saturation have shown great application potentials in nucleic acid research.


Assuntos
Técnicas Biossensoriais/métodos , Nanopartículas de Magnetita/análise , Nanopartículas de Magnetita/química , Ácidos Nucleicos/análise , Ácidos Nucleicos/química , Dióxido de Silício/química , Teste de Materiais
14.
J Nanosci Nanotechnol ; 11(12): 10295-301, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22408901

RESUMO

An improved procedure was described for preparation of monodisperse Fe3O4@SiO2 core-shell magnetic microspheres via solvothermal method followed by a modified Stöber process. The magnetic composite microspheres were characterized with TEM, SEM, FTIR and VSM. Genomic DNA was then extracted from human whole blood using the as synthesized magnetic microspheres on the Eppendorf epMotion5075 workstation. The quality of eluted DNA was evaluated by PCR. The method was very expeditious without using toxic compounds such as phenol or chloroform and can be used for further molecular biology experiments.


Assuntos
DNA/sangue , Compostos Férricos/química , Magnetismo , Microesferas , Dióxido de Silício/química , Sequência de Bases , DNA/isolamento & purificação , Primers do DNA , Eletroforese em Gel de Ágar , Humanos , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Espectroscopia de Infravermelho com Transformada de Fourier
15.
Breast Cancer Res ; 9(1): R7, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17244352

RESUMO

INTRODUCTION: Tamoxifen therapy reduces the risk of recurrence and prolongs the survival of oestrogen-receptor-positive patients with breast cancer. Even if most patients benefit from tamoxifen, many breast tumours either fail to respond or become resistant. Because tamoxifen is extensively metabolised by polymorphic enzymes, one proposed mechanism underlying the resistance is altered metabolism. In the present study we investigated the prognostic and/or predictive value of functional polymorphisms in cytochrome P450 3A5 CYP3A5 (*3), CYP2D6 (*4), sulphotransferase 1A1 (SULT1A1; *2) and UDP-glucuronosyltransferase 2B15 (UGT2B15; *2) in tamoxifen-treated patients with breast cancer. METHODS: In all, 677 tamoxifen-treated postmenopausal patients with breast cancer, of whom 238 were randomised to either 2 or 5 years of tamoxifen, were genotyped by using PCR with restriction fragment length polymorphism or PCR with denaturing high-performance liquid chromatography. RESULTS: The prognostic evaluation performed in the total population revealed a significantly better disease-free survival in patients homozygous for CYP2D6*4. For CYP3A5, SULT1A1 and UGT2B15 no prognostic significance was observed. In the randomised group we found that for CYP3A5, homozygous carriers of the *3 allele tended to have an increased risk of recurrence when treated for 2 years with tamoxifen, although this was not statistically significant (hazard ratio (HR) = 2.84, 95% confidence interval (CI) = 0.68 to 11.99, P = 0.15). In the group randomised to 5 years' tamoxifen the survival pattern shifted towards a significantly improved recurrence-free survival (RFS) among CYP3A5*3-homozygous patients (HR = 0.20, 95% CI = 0.07 to 0.55, P = 0.002). No reliable differences could be seen between treatment duration and the genotypes of CYP2D6, SULT1A1 or UGT2B15. The significantly improved RFS with prolonged tamoxifen treatment in CYP3A5*3 homozygotes was also seen in a multivariate Cox model (HR = 0.13, CI = 0.02 to 0.86, P = 0.03), whereas no differences could be seen for CYP2D6, SULT1A1 and UGT2B15. CONCLUSION: The metabolism of tamoxifen is complex and the mechanisms responsible for the resistance are unlikely to be explained by a single polymorphism; instead it is a combination of several mechanisms. However, the present data suggest that genetic variation in CYP3A5 may predict response to tamoxifen therapy.


Assuntos
Antineoplásicos Hormonais/farmacologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Sistema Enzimático do Citocromo P-450/genética , Tamoxifeno/metabolismo , Tamoxifeno/farmacologia , Idoso , Idoso de 80 Anos ou mais , Arilsulfotransferase/genética , Arilsulfotransferase/metabolismo , Citocromo P-450 CYP2D6/genética , Citocromo P-450 CYP2D6/metabolismo , Citocromo P-450 CYP3A , Sistema Enzimático do Citocromo P-450/metabolismo , Intervalo Livre de Doença , Feminino , Glucuronosiltransferase/genética , Glucuronosiltransferase/metabolismo , Humanos , Pessoa de Meia-Idade , Polimorfismo Genético , Pós-Menopausa , Resultado do Tratamento
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