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1.
Analyst ; 146(17): 5357-5361, 2021 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-34333580

RESUMO

Nitrogen doped carbon dots (N-CDs) were synthesized by a one-step hydrothermal method with dopamine and ethylenediamine. The as-prepared N-CDs were characterized via transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), fluorescence spectrophotometer, UV-Vis spectrophotometry and Fourier transform infrared spectroscopy (FTIR). The average particle dimension of the as-prepared N-CDs was 2.68 nm, and the best excitation and emission wavelengths were 405 nm and 535 nm, separately. N-CDs exhibits excellent selectivity and sensitivity to detect the curcumin (Cur), attaining a wider linear range of 97.5 nM-67.9 µM and a limit of detection (LOD) of as low as 94 nM. Interestingly, N-CDs can also give responsive signals of a visible colour change (yellow to red). Moreover, a novel fluorescent/colorimetric dual-mode method has been successfully employed for the determination of Cur in real samples with good recoveries (94%-110%) and precision (RSD = 0.3-2.9%).


Assuntos
Curcumina , Pontos Quânticos , Carbono , Colorimetria , Corantes Fluorescentes , Nitrogênio , Espectrometria de Fluorescência
2.
J Int Med Res ; 49(8): 3000605211036847, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34407687

RESUMO

A 57-year-old woman was diagnosed with IDH-wildtype (IDHwt) astrocytoma (World Health Organization grade II) with the molecular characteristics of glioblastoma. She underwent concurrent radiotherapy and chemotherapy according to the Stupp protocol in combination with a multi-target antiangiogenic drug and additional intrathecal chemotherapy using methotrexate. During treatment, the patient's tumor showed rapid progression. The chemotherapy with temozolomide was stopped and replaced with radiotherapy combined with tumor treating fields (TTF), the poly (adenosine diphosphate-ribose) polymerase (PARP) inhibitor niraparib, and anlotinib. After the radiotherapy was completed, the symptoms of increased intracranial pressure and epilepsy were well controlled. Considering the patient's tolerance to the treatment, the combined therapy of TTF and anlotinib was continued, and osimertinib, a third-generation epidermal growth factor receptor-tyrosine kinase inhibitor with good permeability of the blood-brain barrier, was added. The patient was regularly followed up and had no obvious adverse drug reactions. Head magnetic resonance imaging (plain scan + enhanced scan) suggested that the lesions were stable. For rapidly progressing glioblastomas or histological grade II/III IDHwt astrocytomas, the combination of TTF and a PARP inhibitor during radiotherapy may have a synergistic effect on tumor control and is well tolerated by patients.


Assuntos
Astrocitoma , Neoplasias Encefálicas , Glioblastoma , Difosfato de Adenosina , Astrocitoma/diagnóstico por imagem , Astrocitoma/tratamento farmacológico , Astrocitoma/radioterapia , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/radioterapia , Feminino , Humanos , Pessoa de Meia-Idade , Ribose
3.
Spectrochim Acta A Mol Biomol Spectrosc ; 256: 119751, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-33819765

RESUMO

The B,N dual-doped carbon dots (B,N-CDs) for ratiometric fluorescence detection the morin were prepared from sodium tetraborate and polyethyleneimine through the single-step hydrothermal method. The B,N-CDs exhibited the optimum excitation and emission wavelength at 340 nm and 467 nm, respectively. Interestingly, the intensities of emission peak at 467 nm of B,N-CDs reduced meanwhile a new peak emerged at 560 nm with the continuous addition of morin, which revealed the ratio fluorescence characteristic between F560nm/F467nm and morin concentration with the linearity range and detection limit of 14.5-32.5 µmol/L and 0.3 µmol/L (S/N = 3), respectively. The interference of common antibiotics and remedies could be ignored when the concentration of morin was detected by the B,N-CDs, which demonstrating the outstanding selectivity. Furthermore, the proposed fluorescence method is used to detect morin in urine with recoveries are 99.8-104.5%. The results of this research indicate the feasibility and practicality of B,N-CDs as an effective fluorescent probe for the determination of morin.


Assuntos
Carbono , Pontos Quânticos , Flavonoides , Fluorescência
4.
J Agric Food Chem ; 69(9): 2836-2844, 2021 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-33621092

RESUMO

In this work, we synthesized carbon nanodots (CNDs) by a one-pot hydrothermal method to carbonize precursors of dry carnation petals and polyethylenimine. The obtained CNDs possess favorable photostability, good biocompatibility, and excellent water solubility, which can serve as a dual-responsive nanosensor for the determination of vitamin B2 (VB2) and pH. A unique ratiometric fluorescence resonance energy transfer probe was developed through a strong interaction between VB2 and surface moieties of CNDs. CNDs emitted at 470 nm; however, in the presence of VB2, an enhanced emission peak was clearly observed at 532 nm. The value of I532/I470 exhibits a stable response to the VB2 concentration from 0.35 to 35.9 µM with a detection limit of 37.2 nM, which has been used for VB2 detection in food and medicine samples and ratiometric imaging of VB2 in living cells with satisfying performance. In addition, the proposed CNDs also displayed pH-sensitive behavior and can be a turn-off fluorescent sensor to monitor pH. The fluorescent intensity at 470 nm is a good linear response against pH values from 3.6 to 8, affording the capability as a single-emissive nanoprobe for intracellular pH sensing.


Assuntos
Carbono , Pontos Quânticos , Corantes Fluorescentes , Concentração de Íons de Hidrogênio , Riboflavina , Vitaminas
5.
Nanoscale ; 12(39): 20482-20490, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-33026004

RESUMO

Green-emissive N,S-self-doped carbon nanodots (N,S-self-CNDs) with an ultrahigh fluorescence (FL) quantum yield (QY) of 60% were synthesized using methyl blue as the only source by a facile hydrothermal approach. The -NH- and -SOx- groups of methyl blue were simultaneously used as nitrogen and sulfur co-dopants to dope into CNDs. The prepared N,S-self-CNDs have an extremely large Stokes shift (∼130 nm) and excitation-independent fluorescence, and are demonstrated to have multiple applications for H2S sensing, bioimaging and anti-counterfeiting. Taking advantage of their excellent optical properties, N,S-self-CNDs could act as a label-free nanoprobe for the detection of H2S. The FL of N,S-self-CNDs could be significantly quenched by H2S because of dynamic quenching, along with excellent selectivity toward H2S from 0.5-15 µM with a detection limit of 46.8 nM. They were successfully employed for the analysis of H2S content in actual samples. Additionally, the nanoprobe was extended to bioimaging in both living PC12 cells and zebrafish, and monitoring H2S in live cells. Furthermore, N,S-self-CNDs have been used to prepare highly fluorescent polymer films by incorporating N,S-self-CNDs in polyvinyl alcohol (PVA). The as-prepared N,S-self-CNDs/PVA films show a prominent dual-mode FL property, implying that they are potential nanomaterials in the anti-counterfeiting field.


Assuntos
Carbono , Nanoestruturas , Animais , Fluorescência , Nitrogênio , Peixe-Zebra
6.
BMC Ophthalmol ; 20(1): 207, 2020 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-32450821

RESUMO

BACKGROUND: The traditional view is that there are no vessels in the foveal avascular zone. The two cases we report show microvessels crossing the foveal avascular zone. CASE PRESENTATION: A man and a woman, both 25 years old, were both incidentally found on optical coherence tomography angiography (OCTA) to have unilateral aberrant microvessels crossing the foveal avascular zone in their left eyes. Visual acuity was preserved in both patients. The vessel density (VD) and perfusion density (PD) of the eyes with the aberrant microvessels were all higher than those of the contralateral eyes. Nevertheless, measurements of foveal avascular zone (FAZ) dimensions, including its area, perimeter and circularity, were smaller in the left eyes than in the right eyes. No complications were recorded. CONCLUSIONS: To date, aberrant microvessels crossing the foveal avascular zone have not been found to impair visual function. OCTA is a non-invasive and quick method that does not require dilation or the use of fluorescein dye. It is a reliable tool for the detection of aberrant microvessels crossing the foveal avascular zone.


Assuntos
Anormalidades do Olho/diagnóstico por imagem , Fóvea Central/irrigação sanguínea , Vasos Retinianos/anormalidades , Malformações Vasculares/diagnóstico por imagem , Adulto , Feminino , Angiofluoresceinografia , Humanos , Pressão Intraocular/fisiologia , Masculino , Microvasos/anormalidades , Imagem Multimodal , Fotografação , Estudos Retrospectivos , Tomografia de Coerência Óptica , Acuidade Visual/fisiologia , Campos Visuais/fisiologia
7.
Talanta ; 216: 120943, 2020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-32456917

RESUMO

A novel ratiometric emission N, S dual-doped carbon dots (N, S-CDs) were facilely developed for pH visual sensing via one-step hydrothermal method. The proposed N, S-CDs displayed intrinsic pH-sensitive behavior and exhibited ratiometric fluorescence emission (F563 nm/F645 nm) characteristic with the variation of pH values. Interestingly, a significant red shift of emission wavelength can be observed at 645 nm along with the emission at 563 nm decreased accordingly when the pH changed from 3.0 to 1.0. Simultaneously, the fluorescence of N, S-CDs aqueous solution was visually varied from yellow to red. The ratiometric pH linear response was in the region of 3.6 to 2.4 and the pKa was 2.90. Moreover, the N, S-CDs hold unique optical properties, good reversibility, superior biocompatibility and low cytotoxicity, which was further employed to monitor the intracellular pH fluctuations through the visible fluorescence changes between yellow and red. All these findings demonstrated that N, S-CDs can be utilized as the visual biosensor platform for tracking pH variations in extremely acidic environments such as gastric juice, which provided novel insights for clinical medical disease diagnosis (e.g., stomach disease detection) and other biomedical fields.


Assuntos
Carbono/química , Corantes Fluorescentes/química , Imagem Óptica , Pontos Quânticos/química , Técnicas Biossensoriais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/farmacologia , Humanos , Concentração de Íons de Hidrogênio , Tamanho da Partícula , Espectrometria de Fluorescência , Propriedades de Superfície
8.
J Mater Chem B ; 8(23): 5089-5095, 2020 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-32406457

RESUMO

Multifunctional N-doped carbon nanodots (N-CNDs) with a fluorescence (FL) quantum yield (QY) of 13.6% have been synthesized via a facile one-step hydrothermal process using Artemisia annua and 1,2-ethylenediamine as precursors. As-prepared N-CNDs showed excellent FL properties and were developed as a multifunctional sensing platform for vitamin B12 (VB12) and Co2+ determination, and bioimaging in living cells and zebrafish. The FL of N-CNDs is quenched efficiently in the presence of VB12 on the basis of the inner filter effect (IFE) or Co2+ by static quenching, respectively. EDTA as a masking agent enables Co2+ to be effectively eliminated and N-CNDs were used to selectively detect VB12 in the presence of both VB12 and Co2+. The present FL nanosensor can detect VB12 and Co2+ in the linear ranges of 0.5-35 µM and 2.5-25 µM with the corresponding detection limits of 47.4 nM and 230.5 nM, respectively. The study proved that the determination of Co2+ was based on the static quenching to form a complex between the amino group of N-CNDs and Co2+. Inspired by these outstanding properties, practical applications of this nanosensor for the detection of VB12 in actual samples (human serum, egg yolk, VB12 tablets and VB12 injection) and Co2+ in water samples were further verified with satisfactory results. The as-constructed N-CNDs have negligible toxicity and good biocompatibility, which facilitates utilization of N-CNDs in bioimaging of A549 cells and zebrafish, and sensing VB12 in living cells.


Assuntos
Carbono/química , Cobalto/análise , Nanopartículas/química , Imagem Óptica , Pontos Quânticos/química , Vitamina B 12/análise , Células A549 , Animais , Humanos , Tamanho da Partícula , Propriedades de Superfície , Peixe-Zebra
9.
Talanta ; 206: 120243, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31514864

RESUMO

A facile and rapid synthesis of multifunctional carbon nanodots (CNDs) was developed by using the acid-base neutralization spontaneous heat with glucose as precursor, 1,2-ethylenediamine (EDA) and concentrated nitric acid as dual N-dopants. The CND has a tremendous antioxidant potency, which represents effective inhibitory concentrations of reactive oxygen species that are significantly lower than ascorbic acid. Furthermore, minimum inhibitory concentration (MIC) assay revealed CNDs possessed significant antimicrobial activity for Gram-positive S. aureus and Gram-negative E. coli. Moreover, the CNDs are endowed with favorable fluorescence (FL) behaviors including the quantum yield (QY) of 14.2% and stable FL within a wide range of pH and high tolerance to external ionic strength, rendering them applicable in quercetin (QCT) detection as a FL nanoprobe. The CNDs were effectively quenched by QCT due to static quenching which takes place by the electrostatic interaction between basic groups of CNDs and QCT of 3-hydroxyl. This nanoprobe had profitable selectivity and sensitivity towards QCT with a linearity ranging from 1 µM to 47 µM and a low detection limit of 172.4 nM and were successfully performed for QCT detection in human serum and urine samples.


Assuntos
Antibacterianos/farmacologia , Carbono/química , Corantes Fluorescentes/farmacologia , Sequestradores de Radicais Livres/farmacologia , Pontos Quânticos/química , Quercetina/análise , Antibacterianos/síntese química , Antibacterianos/química , Bacillus subtilis/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/química , Sequestradores de Radicais Livres/síntese química , Sequestradores de Radicais Livres/química , Humanos , Limite de Detecção , Quercetina/sangue , Quercetina/urina , Espectrometria de Fluorescência/métodos , Staphylococcus aureus/efeitos dos fármacos
10.
Ann Palliat Med ; 8(5): 752-757, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31865735

RESUMO

Apatinib, a novel tyrosine kinase inhibitor, has anti-angiogenetic effect just as bevacizumab. Although bevacizumab has been used successfully in treating cerebral radiation necrosis, there has yet not any report on that apatinib can treat pseudoprogression with symptoms. Here we report a case of glioblastoma multiforme (GBM) patient with pseudoprogression after receiving the concurrent chemoradiotherapy, which was successfully treated by apatinib. A 51-year-old woman had multiple intracranial lesions (left parietal and right frontal), the primary left parietal lesion was surgically removed and was pathologically confirmed as glioblastoma (WHO grade IV). Then the patient received postoperative temozolomide with concurrent chemoradiotherapy. Three weeks after the radiotherapy, the patient experienced increased intracranial pressure and seizure. Magnetic resonance imaging (MRI) T1 enhancement examination showed an increase of abnormal enhancement range in the area of irradiation. After multiple disciplinary team (MDT) discussion, the patient was diagnosed with pseudoprogression after radiotherapy. Then she was given apatinib for 8 weeks at a dose of 500 mg qd. During the treatment period, the clinical symptoms and corresponding nerve images of the patient have been rapidly improved. In 12 months after the radiotherapy, progression of tumor in the primary site has not been discovered. Apatinib showed a good therapeutic effect and tolerance for the development of pseudoprogression advances with obvious symptoms.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Glioblastoma/tratamento farmacológico , Piridinas/uso terapêutico , Neoplasias Encefálicas/patologia , Feminino , Glioblastoma/patologia , Humanos , Pessoa de Meia-Idade
11.
Opt Express ; 27(19): 27046-27061, 2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31674573

RESUMO

We present an efficient and faithful hyperentanglement purification protocol (hyper-EPP) for three-photon system in mixed hyperentangled Greenberger-Horne-Zeilinger states with bit-flip errors in both spatial-mode and polarization degrees of freedom (DOFs), resorting to the fidelity-robust quantum gates and hyperentanglement link. Our high-efficiency hyper-EPP comes from two aspects. One is to pump the higher-fidelity hyperentanglement from different three-photon systems into the same three-photon system with fidelity-robust swap gates, the other is to reproduce some hyperentangled three-photon systems from hyperentangled two-photon subsystems based on hyperentanglement link. Moreover, as the infidelity originating from imperfect single-photon scattering can be heralded as a failure by triggering a detector, our hyper-EPP operates faithfully with the present quantum circuits. Furthermore, our hyper-EPP can be directly extended to purify multiple photon systems entangled in one DOF or hyperentangled in multiple DOFs.

12.
Analyst ; 144(22): 6729-6735, 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31612877

RESUMO

The conjugation of ligands to nanoparticles as drug delivery systems that target specific cells is a promising approach for the delivery of therapeutic agents to tumor cells. Herein, we prepared green-emission fluorescent carbon nanodots (CNDs) by a facile hydrothermal method with d-(+)-glucosamine hydrochloride and l-aspartic acid as the precursors, then covalently conjugated with folate (FA), polyethyleneimine (PEI) and hyaluronic acid (HA) to develop dual ligand-decorated nanocarriers (FA-PEI-HA-CNDs) for the targeted imaging of cancer cells. FA-PEI-HA-CNDs integrated the excellent fluorescence property of CNDs, and can be used for the real-time and noninvasive location tracking of cancer cells. The cellular uptake study demonstrated that FA-PEI-HA-CNDs markedly improved the internalization efficiency in A-549 cells via folate/CD44 receptor-mediated endocytosis in comparison with that of the A549 cells pretreated with excess FA, HA, and FA and HA. Therefore, these dual folate/CD44 receptor-targeted CNDs (FA-PEI-HA-CNDs) show promising potential for cancer detection, drug delivery, and individualized treatment as performance platforms.


Assuntos
Corantes Fluorescentes/química , Pontos Quânticos/química , Células A549 , Carbono/química , Carbono/toxicidade , Endocitose/efeitos dos fármacos , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/toxicidade , Receptores de Folato com Âncoras de GPI/metabolismo , Ácido Fólico/análogos & derivados , Ácido Fólico/síntese química , Ácido Fólico/toxicidade , Humanos , Receptores de Hialuronatos/metabolismo , Ácido Hialurônico/análogos & derivados , Ácido Hialurônico/síntese química , Ácido Hialurônico/toxicidade , Ligantes , Microscopia Confocal/métodos , Microscopia de Fluorescência/métodos , Polietilenoimina/análogos & derivados , Polietilenoimina/síntese química , Polietilenoimina/toxicidade , Pontos Quânticos/toxicidade
13.
Opt Express ; 27(13): 17493-17506, 2019 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-31252708

RESUMO

The two or more degrees of freedoms (DOFs) of photon systems are very useful in hyperparallel photonic quantum computing to accomplish more quantum logic gate operations with less resource, and depress photonic dissipation noise in quantum information processing. We present some flexible and adjustable schemes for hybrid hyper-controlled-not (hyper-CNOT) gates assisted by low-Q cavities, on the two-photon systems in both the spatial-mode and the polarization DOFs. These hybrid spatial-polarization hyper-CNOT gates consume less quantum resource and are more robust against photonic dissipation noise, compared with the integration of two cascaded CNOT gates in one DOF. Besides, simultaneous counter-propagation of two photons economize extremely the operation time in the whole process of our schemes. Moreover, these quantum logic gates are more feasible for fast quantum operations in the weak-coupling region of the low-Q cavities with current experimental technology, which are much different from strong-coupling cases of the high-Q ones.

14.
Artigo em Inglês | MEDLINE | ID: mdl-30822735

RESUMO

A fluorescent sulfur and nitrogen dual-doped carbon dots (S,N-CDs) was prepared by a simple and one-step acid-base neutralization and exothermic carbonization method. Hexavalent chromium (Cr(VI)) could effectively quench the fluorescence of S,N-CDs based on inner filter effect (IFE) and dynamic quenching, whereas ascorbic acid (AA) could recover the fluorescence of S,N-CDs/Cr(VI) because of IFE weakening. So an "on-off-on" and label-free nano-probe consecutive determination of Cr(VI) and AA was constructed. This nano-probe system demonstrated excellent selectivity and sensitivity to Cr(VI) and AA with linear range of 0.065-198 µmol/L (3.38-10,296 µg/L) and 6.6-892 µmol/L (1.16-157 mg/L), respectively. Meanwhile, the as-prepared S,N-CDs possess low toxicity and could be used for multi-color cell imaging in SMMC 7721 cells. More importantly, this nano-probe was successfully employed for detection of Cr(VI) in tap water and AA in food samples. In view of its simple detection condition, rapid response, wide linear range, low detection limit and inexpensive instrument, the as-constructed nano-probe system could have a wide range of potential application, including water quality monitoring and evaluation, food inspection and testing and biomedical analysis.


Assuntos
Ácido Ascórbico/análise , Cromo/análise , Pontos Quânticos/química , Espectrometria de Fluorescência/métodos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Frutas/química , Humanos , Limite de Detecção , Modelos Lineares , Pontos Quânticos/toxicidade , Reprodutibilidade dos Testes
15.
ACS Biomater Sci Eng ; 5(9): 4692-4699, 2019 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-33448841

RESUMO

Because of the demand for precision medicine, the investigatation on the application of carbon-dots-based nanosystems in the field of biomedicine is attracting more and more attention. Therefore, we have built a multifunctional nanosystem based on sulforaphane-conjugated carbon dots (SFN-CDs) with thiourea skeleton and applied for EGFR-overexpressing cancer cells targeted imaging and inhibiting. The SFN-CDs are formed by grafting sulforaphane on the amino-rich yellow fluorescent carbon dots, which have excellent optical stability and can be distinguished from normal cells for targeted imaging of cancer cells. The vitro toxicity experiments demonstrated that the SFN-CDs can effectively inhibit EGFR-overexpressing cancer cell proliferation at concentrations below 100 µg mL-1. All these results validated that SFN-CDs nanoparticles with integration of diagnostic and therapeutic functions can be used as a potential nanodurg in early stage of cancer control. Moreover, this work provides useful insight into targeted nanoparticle design in the biological nanomedicine field.

16.
Talanta ; 179: 554-562, 2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29310274

RESUMO

A fluorescent nanoprobe based on nitrogen-doped carbon dots (N-CDs) with green fluorescent emission have been fabricated through a facile one-step hydrothermal treatment using catechol and triethylene tetramine as precursors. The obtained N-CDs with excellent luminescent properties and superior biocompatibility have been applied for the development of a bifunctional sensor for the detection of Fe3+ and ascorbic acid (AA). Fe3+ that are tightly chelating the surface of N-CDs can induce fluorescence (FL) quenching of N-CDs through photo-induced electron transfer (PET). Meanwhile, the addition of AA serves to shelter the CDs effectively from being quenched by Fe3+ due to AA, as an antioxidant, enable easy-conversion of Fe3+ to reduced states (i.e. Fe3+ and Fe2+). The N-CDs are used as a facile and label-free "on-off-on" fluorescent nanoprobe for the determination of Fe3+ and AA with detection limits of 58.82nM and 0.236µM with the corresponding linear ranges of 25-200µM and 25-300µM, respectively. According to this phenomenon, an "AND" logic gate based on the novel N-CDs has been constructed. As-prepared N-CDs with negligible toxicity and perfect biocompatibility were expanded for cellular imaging and sensing Fe3+ and AA in living cell, which enlarges the application range of the N-CDs. Most importantly, the as-constructed fluorescent sensing system was successfully applied to detection of Fe3+ in tap water and the analyses of AA in fresh fruits with satisfactory results.


Assuntos
Ácido Ascórbico/análise , Técnicas Biossensoriais , Água Potável/química , Frutas/química , Ferro/análise , Pontos Quânticos/química , Actinidia/química , Carbono/química , Catecóis/química , Citrus sinensis/química , Corantes Fluorescentes/química , Limite de Detecção , Nanoestruturas/química , Nitrogênio/química , Oxirredução , Espectrometria de Fluorescência/métodos , Trientina/química , Vitis/química
17.
Sci Rep ; 6: 35922, 2016 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-27804973

RESUMO

Entanglement concentration protocol (ECP) is used to extract the maximally entangled states from less entangled pure states. Here we present a general hyperconcentration protocol for two-photon systems in partially hyperentangled Bell states that decay with the interrelation between the time-bin and the polarization degrees of freedom (DOFs), resorting to an input-output process with respect to diamond nitrogen-vacancy centers coupled to resonators. We show that the resource can be utilized sufficiently and the success probability is largely improved by iteration of the hyper-ECP process. Besides, our hyper-ECP can be directly extended to concentrate nonlocal partially hyperentangled N-photon Greenberger-Horne-Zeilinger states, and the success probability remains unchanged with the growth of the number of photons. Moreover, the time-bin entanglement is a useful DOF and it only requires one path for transmission, which means it not only economizes on a large amount of quantum resources but also relaxes from the path-length dispersion in long-distance quantum communication.

18.
Biochem Pharmacol ; 118: 18-30, 2016 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-27520484

RESUMO

It is believed that tumor cells can give rise to endothelial cells and tumor endothelium has a neoplastic origin. Yet, the stimuli and underlying mechanism remain unclear. Here, we demonstrate that adriamycin or paclitaxel, first-line chemotherapy agent, induced breast cancer cells to generate morphological, phenotypical and functional features of endothelial cells in vitro. In xenografts models, challenges from adriamycin or paclitaxel induced cancer cells to generate the majority of microvessels. Importantly, in breast cancer specimens from patients with neoadjuvant anthracycline-based or taxane-based chemotherapy, tumor-derived endothelial microvessels, lined by EGFR-amplified or/and TP53+-CD31+ endothelial cells, was significantly higher in patients with progressive or stable disease (PD/SD) than in those with a partial or complete response (PR/CR). Further, exposure to the Notch signaling inhibitor and gene silencing studies showed that Notch signaling inhibition or silencing Nothc4/Dll3 decreased endothelial markers and function of tumor-derived endothelial cells under chemotherapy treatment, which may be through VEGFR3. Thus, our findings demonstrate that chemotherapy induces functional tumor-derived endothelial microvessels by mediating Notch signaling and VEGF signaling, and may provide new targets for anti-angiogenesis therapy in breast cancer.


Assuntos
Antineoplásicos/efeitos adversos , Neoplasias da Mama/tratamento farmacológico , Endotélio Vascular/efeitos dos fármacos , Proteínas de Neoplasias/agonistas , Neovascularização Patológica/induzido quimicamente , Receptores Notch/agonistas , Transdução de Sinais/efeitos dos fármacos , Animais , Antraciclinas/efeitos adversos , Antraciclinas/uso terapêutico , Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/toxicidade , Biomarcadores/metabolismo , Neoplasias da Mama/irrigação sanguínea , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Hidrocarbonetos Aromáticos com Pontes/efeitos adversos , Hidrocarbonetos Aromáticos com Pontes/uso terapêutico , Doxorrubicina/efeitos adversos , Doxorrubicina/uso terapêutico , Endotélio Vascular/metabolismo , Endotélio Vascular/patologia , Feminino , Humanos , Células MCF-7 , Camundongos Nus , Microvasos/efeitos dos fármacos , Microvasos/metabolismo , Microvasos/patologia , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Neovascularização Patológica/metabolismo , Neovascularização Patológica/patologia , Paclitaxel/efeitos adversos , Paclitaxel/uso terapêutico , Interferência de RNA , Receptores Notch/antagonistas & inibidores , Receptores Notch/genética , Receptores Notch/metabolismo , Organismos Livres de Patógenos Específicos , Taxoides/efeitos adversos , Taxoides/uso terapêutico , Ensaios Antitumorais Modelo de Xenoenxerto
19.
Oncol Lett ; 9(6): 2675-2679, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26137127

RESUMO

Colon cancer has a high incidence in individuals >60-years-old. The commonly used chemotherapeutic agent, 5-fluorouracil (5-FU), has gradually lost its potency in treating colorectal cancer following the acquisition of resistance. Drug resistance is usually associated with epithelial-mesenchymal transitions (EMTs) in cancer cells. In the present study, the EMT phenotypes of two colon cancer cell lines, wild-type (HCT-8/WT) and 5-FU-resistant (HCT-8/5-FU), were characterized following the analysis of cellular migration, proliferation, morphology and molecular changes. In order to further clarify the mechanism of EMT in HCT-8/5-FU cells, the effect of EMT pathway inhibitors upon drug sensitivity was investigated. The results revealed that the Hedgehog signaling pathway inhibitor, GDC0449, reversed drug resistance. Therefore, inhibition of the Hedgehog pathway may provide a novel chemotherapeutic strategy for the treatment of patients with 5-FU-resistant colon cancer.

20.
Biomed Rep ; 3(4): 543-548, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26171163

RESUMO

O6-methylguanine-DNA methyltransferase (MGMT) promoter methylation is a conventional technique to predict the prognosis or individualized treatment of glioma in tumor tissue following surgery or biopsy. However, the technique cannot be applied in those glioma patients with concomitant neurological dysfunctions or advanced age. The present study aimed to find a new minimally invasive and efficient alternative method for the detection of MGMT promoter methylation. The expression of MGMT promoter methylation was assessed in peripheral blood and cerebrospinal fluid (CSF), and compared to the corresponding tumor tissue from glioma patients. The 89 patients in the study [32 World Health Organization (WHO) grade II, 19 WHO grade III and 38 WHO grade IV) were pathologically-diagnosed glioma and received radiation therapy following sample collection. The resected glioma tumor tissue (89), corresponding serum (89) and CSF (78) samples were collected for the detection of MGMT promoter methylation using methylation-specific polymerase chain reaction. The sensitivity and specificity of detecting MGMT promoter methylation in CSF and serum were compared. Among the tumor tissue samples, 51/89 (57.3%) showed MGMT promoter methylation. The specificity of the detection in the CSF and serum samples reached 100%. The sensitivity of MGMT promoter methylation detection in CSF and serum were 26/40 (65.0%) and 19/51 (37.3%), respectively (P<0.05). In the WHO II, III and IV subgroups, the sensitivities of MGMT promoter methylation detection using CSF were 8/12 (66.7%), 11/18 (61.1%) and 7/10 (70.0%), respectively, which were significantly higher than the sensitivities using serum (7/21, 33.3%; 7/19, 36.8%; and 5/11, 45.5%, respectively P<0.05). Among patients with residual postoperative tumors, the sensitivities of detecting MGMT promoter methylation using CSF and serum were 18/25 (72.0%) and 10/24 (41.7%), respectively, both of which were significantly higher than the corresponding values for patients without residual tumors (8/15, 53.3% and 6/19, 31.6%, respectively; P<0.05). The detection of MGMT promoter methylation in CSF specimens shows higher sensitivity compared to the serum for glioma patients. Assessment of MGMT promoter methylation in CSF may provide a promising clinical methodology for early diagnosis, individual treatment, monitoring of recurrence and prognosis for glioma patients.

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