Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 6.981
Filtrar
1.
Adv Exp Med Biol ; 1131: 73-91, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31646507

RESUMO

Imaging techniques may overcome the limitations of electrode techniques to measure locally not only membrane potential changes, but also ionic currents. Here, we review a recently developed approach to image native neuronal Ca2+ currents from brain slices. The technique is based on combined fluorescence recordings using low-affinity Ca2+ indicators possibly in combination with voltage sensitive dyes. We illustrate how the kinetics of a Ca2+ current can be estimated from the Ca2+ fluorescence change and locally correlated with the change of membrane potential, calibrated on an absolute scale, from the voltage fluorescence change. We show some representative measurements from the dendrites of CA1 hippocampal pyramidal neurons, from olfactory bulb mitral cells and from cerebellar Purkinje neurons. We discuss the striking difference in data analysis and interpretation between Ca2+ current measurements obtained using classical electrode techniques and the physiological currents obtained using this novel approach. Finally, we show how important is the kinetic information on the native Ca2+ current to explore the potential molecular targets of the Ca2+ flux from each individual Ca2+ channel.


Assuntos
Canais de Cálcio , Neuroimagem , Animais , Cálcio/metabolismo , Canais de Cálcio/fisiologia , Dendritos/fisiologia , Humanos , Potenciais da Membrana/fisiologia , Imagem Óptica , Células Piramidais/fisiologia
2.
Braz Oral Res ; 33: e0088, 2019 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-31531566

RESUMO

The main of the study was quantify the effect of two ceramics with two underlying resin cements on apparent fluorescence levels. Buccal surfaces of two bovine incisors were ground flat producing one enamel and one dentin substrate. The veneers were fabricated (0.5 and 1.0 mm thickness) using two ceramics (IPSe.max Press and IPSe.max Zirpress, Ivoclar Vivadent). Veneers were cemented using either light-cured (Variolink II, Ivoclar Vivadent) or self-adhesive dual (Rely X U200, 3M ESPE) cement. The layered Control group materials had no cement application. Semi-quantitative fluorescence image analysis (Matlabs software, Matworks) involved processing the images as captured under each daylight (DL, Gretagmacbeth) and ultraviolet illuminants (UVA, Sylvania) within a neutral-gray lightbox (Macbeth Spectral Light). Statistical analysis of the quantitative fluorescence values was performed using two-way ANOVA and Tukey's test (p < 0.05). The e.max Zirpress on the dentin substrate produced greater fluorescence (p < 0.05) when subjected to UV illumination and more fluorescence (p < 0.05) than e.max Press in both cement groups. Light-cured cement produced higher (p < 0.05) fluorescence than the dual-cement with e.max Press on enamel under UV illumination. The fluorescence for e.max Press on the dentin substrate was greater (p < 0.05) than for e.max Zirpress using dual self-adhesive cement subjected to daylight illumination. Thus, it is possible to conclude that the combination of ceramic and cement produce definite, significant effects on the apparent fluorescence, vital quality for restorative dentistry.


Assuntos
Cerâmica/química , Facetas Dentárias , Imagem Óptica/métodos , Cimentos de Resina/química , Animais , Bovinos , Esmalte Dentário/química , Esmalte Dentário/efeitos dos fármacos , Dentina/química , Dentina/efeitos dos fármacos , Luz , Teste de Materiais , Valores de Referência , Reprodutibilidade dos Testes , Propriedades de Superfície
3.
Nihon Yakurigaku Zasshi ; 154(3): 121-127, 2019.
Artigo em Japonês | MEDLINE | ID: mdl-31527361

RESUMO

Hydrogen sulfide (H2S) has been reported to play an important role in biological systems. More recently, sulfane sulfur (sulfur with 0 or -1 charge) molecules have been also reported to be involved in various biological phenomena such as regulation of redox signaling and antioxidant functions. Fluorescent probes are one of the important chemical tools because it is easy to use and enable the real-time detection of the target molecules in living cells and tissues. We have successfully developed a highly selective H2S-detecting fluorescent probe, HSip-1. HSip-1 has been designed on the basis of the facts that the macrocyclic polyamine ligands form a stable complex with Cu2+, and Cu2+ also reacts with H2S and make a stable CuS complex. SSip-1 is a fluorescent probe for detecting sulfane sulfur and this fluorescent probe is designed on the basis of the unique feature of sulfane sulfur to bind reversibly to other sulfur atoms and the intramolecular spirocyclization reaction of xanthene dyes. SSip-1 is a highly selective fluorescent probe and can detect sulfane sulfur reversibly. Both HSip-1 and SSip-1 were able to be used for the live-cell fluorescence imaging. Further, we applied HSip-1 to the high-throughput screening (HTS) for the inhibitors of 3-mercaptopyruvate sulfurtransferase (3MST), one of the reactive sulfur species (RSS)-generating enzymes. We successfully found new 3MST inhibitors by screening of 174,118 compounds. We expect that these fluorescent probes and inhibitors would be useful to elucidate new functions of RSS and RSS-generating enzymes.


Assuntos
Corantes Fluorescentes , Enxofre/análise , Sulfurtransferases/antagonistas & inibidores , Ensaios de Triagem em Larga Escala , Humanos , Sulfeto de Hidrogênio , Imagem Óptica , Transdução de Sinais
4.
Chem Commun (Camb) ; 55(75): 11263-11266, 2019 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-31475257

RESUMO

A reversible fluorescent probe (NP) for sensing SO2 and FA was rationally constructed. With the outstanding attributes of NP, the fluctuation of endogenous SO2 and FA was successfully traced, not only at the cellular level, but also in living mice for the first time. Significantly, it was first found that the interaction of SO2 and FA can attenuate the cytotoxicity.


Assuntos
Corantes Fluorescentes/química , Formaldeído/análise , Dióxido de Enxofre/análise , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Corantes Fluorescentes/administração & dosagem , Corantes Fluorescentes/síntese química , Formaldeído/farmacologia , Células HeLa , Humanos , Injeções Intraperitoneais , Camundongos , Estrutura Molecular , Imagem Óptica , Espectrometria de Fluorescência , Dióxido de Enxofre/farmacologia
6.
Chem Commun (Camb) ; 55(76): 11358-11361, 2019 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-31482158

RESUMO

We report on a dual ratiometric two-photon fluorescent probe for in situ sensing of mitochondrial CE activity and pH. Using the probe it is possible to visualize the CE-mediated acidification of hepatoma cells and hepatic tissues during medication with antipyretic anti-inflammatory drugs.


Assuntos
Carboxilesterase/análise , Corantes Fluorescentes/química , Mitocôndrias/metabolismo , Imagem Óptica , Fótons , Anti-Inflamatórios não Esteroides/farmacologia , Antipiréticos/farmacologia , Carboxilesterase/metabolismo , Proliferação de Células/efeitos dos fármacos , Células Hep G2 , Humanos , Concentração de Íons de Hidrogênio , Fígado/efeitos dos fármacos , Fígado/metabolismo , Mitocôndrias/efeitos dos fármacos
7.
Medicine (Baltimore) ; 98(36): e16935, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31490376

RESUMO

BACKGROUND: Although several previous studies demonstrated the feasibility and efficacy of indocyanine green (ICG) for thyroid cancer surgery, ICG was administered through venous injection and focused on parathyroid gland protection. We thus aimed to study the feasibility of imaging using ICG combined with carbon nanoparticles (CNs) in the identification of sentinel lymph nodes (SLNs) in patients diagnosed with papillary thyroid microcarcinoma (PTMC). METHODS: Two approaches were applied to detect lymph nodes in PTMC surgery. Patients were randomized into 2 groups. ICG and CNs were injected into the thyroid in Group A. In Group B, only CNs was injected. Black-stained or fluorescent nodes observed using near-infrared fluorescence imaging systems were defined as SLNs. SLN and central lymph node (CLN) dissection was completed in both groups. The pathological and postoperative outcomes were compared between 2 groups. RESULTS: There were 40 patients in Group A and 60 in Group B. A total of 138 SLNs were identified; 72 and 66 SLNs were detected and dissected in Groups A and B, respectively. The number of SLNs identified (per patient) in Group A was higher than that in Group B (P = .027). The number of harvested CLNs was 161 and 192 in Groups A and B, respectively, out of which 45 and 48 lymph nodes with metastasis were confirmed by permanent pathology. The CLN metastatic rate in Group A was higher than that in Group B (P = .048). CONCLUSION: Imaging using ICG combined CNs is feasible and safe for SLN identification in PTMC patients. Compared with using only CNs, more SLNs can be removed and more metastatic lymph nodes can be confirmed when using the combined method. Although the combined method appears to accurately stage tumors, further research is needed.


Assuntos
Carbono/administração & dosagem , Carcinoma Papilar/patologia , Verde de Indocianina/administração & dosagem , Excisão de Linfonodo/métodos , Nanopartículas/administração & dosagem , Linfonodo Sentinela/cirurgia , Neoplasias da Glândula Tireoide/patologia , Adulto , Carbono/química , Carcinoma Papilar/cirurgia , Corantes/administração & dosagem , Estudos de Viabilidade , Feminino , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Nanopartículas/química , Imagem Óptica/métodos , Linfonodo Sentinela/patologia , Neoplasias da Glândula Tireoide/cirurgia , Tireoidectomia/métodos
8.
Zhonghua Zhong Liu Za Zhi ; 41(9): 654-658, 2019 Sep 23.
Artigo em Chinês | MEDLINE | ID: mdl-31550854

RESUMO

Objective: This study aims to explore the clinical value of fusion indocyanine green fluorescence imaging (FIGFI) in total laparoscopic radical resection for right colon cancer. Methods: From October, 2018 to December, 2018, 15 patients who underwent total laparoscopic radical resection for right colon cancer using FIGFI in Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College were retrospectively enrolled in this study. Data regarding surgical outcomes, postoperative recovery, pathological outcomes and complications were collected and analyzed. Results: All patients successfully underwent total laparoscopic radical resection for right colon cancer using FIGFI. 1 patients (6.7%) received extended resection of bowel due to poor blood supply after mesentery excision. The average operation time was 133.7 minutes and intraoperative blood loss was 26.7 ml. The average time to ground activities, fluid diet intake, first flatus and postoperative hospitalization were 19.1 h, 11.7 h, 32.5 h and 5.0 d, respectively. The average length of tumor was 4.5 cm. The average proximal and distal resection margins were 14.9 cm and 12.1 cm, respectively. The average number of lymph nodes retrieved was 29.3 per patient. Only one patient suffered from incisional fat liquefaction after surgery and was managed effectively by regular dressing change. No severe complications such as indocyanine green allergy, anastomotic stenosis, anastomotic leakage, abdominal bleeding, bowel obstruction, pulmonary infection, and abdominal infection occurred in any patients. Conclusions: FIGFI is helpful to judge the blood supply of intestinal segments and anastomotic stoma in total laparoscopic radical resection for right colon cancer quickly. It is a safe and feasible technique with satisfactory short-term effect.


Assuntos
Anastomose Cirúrgica/métodos , Colectomia/métodos , Colo/irrigação sanguínea , Neoplasias do Colo/cirurgia , Corantes/administração & dosagem , Verde de Indocianina/administração & dosagem , Imagem Óptica/métodos , Fístula Anastomótica/prevenção & controle , Colo/cirurgia , Procedimentos Cirúrgicos do Sistema Digestório/métodos , Estudos de Viabilidade , Humanos , Laparoscopia/métodos , Estudos Retrospectivos , Resultado do Tratamento
9.
Chem Commun (Camb) ; 55(82): 12308-12311, 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31556426

RESUMO

Herein, we developed a dual-channel and light-up near-infrared fluorescent probe for ratiometric sensing of ß-galactosidase (ß-gal) activity. The well-designed probe, which shows ratiometric optical response with a significant red-shift (from 575 nm to 730 nm), was successfully applied to detect endogenous ß-gal activity in SKOV-3 cells and tumor-bearing mice.


Assuntos
Corantes Fluorescentes/análise , Corantes Fluorescentes/química , beta-Galactosidase/análise , beta-Galactosidase/metabolismo , Animais , Linhagem Celular Tumoral , Células Hep G2 , Humanos , Raios Infravermelhos , Camundongos , Camundongos Nus , Estrutura Molecular , Neoplasias Experimentais/diagnóstico por imagem , Imagem Óptica
10.
Chem Commun (Camb) ; 55(82): 12352-12355, 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31559405

RESUMO

We report a new biofunctionalized nanoplatform based on hyaluronic acid-coated gold-nano-dot-decorated hollow carbon nanospheres (AuHCNs-HA) for microRNA imaging in living cells. Importantly, the HA-coated nanoplatform could be internalized into target cells via CD44 receptor-mediated endocytosis. It can be further applied for intracellular miR-21 imaging in CD44-positive colorectal cancer cells.


Assuntos
Neoplasias Colorretais/metabolismo , Ouro/química , Nanopartículas Metálicas/química , MicroRNAs/análise , Imagem Óptica/métodos , Receptores de Hialuronatos/metabolismo , Ácido Hialurônico/química , Imagem Óptica/instrumentação , Tamanho da Partícula , Porosidade , Propriedades de Superfície
11.
Inorg Chem ; 58(18): 12422-12432, 2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31483641

RESUMO

Fluorescence imaging is a powerful tool in biomedical research. It has been frequently used to uncover or better understand physiological mechanisms in disease-related processes such as cancer. The majority of chromophores used for imaging are based on a 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene (BODIPY) scaffold. However, their applications are limited due to their poor water solubility as well as poor cancer cell selectivity. To circumvent these drawbacks, we present herein the use of bis(dipyrrinato)zinc(II) complexes. As this class of compounds is associated with a quenching effect of the excited state in water, the lead compound of this study (3) was encapsulated in a polymer matrix with biotin as a targeting moiety (3-NP). This encapsulation improved the water solubility, overcame the quenching effects in water, as well as allowed selective accumulation in the lysosomes with a bright fluorescence signal in monolayer cells as well as 3D multicellular tumor spheroids (MCTS). As a benefit from the biotin targeting moiety, the nanoparticles were majorly taken up by the sodium dependent multivitamin transporter (SMVT) which is overexpressed in various cancers cells and selectively accumulated in cancerous cells over noncancerous cells.


Assuntos
Corantes Fluorescentes/química , Lisossomos/patologia , Nanopartículas/química , Neoplasias/patologia , Polímeros/química , Pirróis/química , Zinco/química , Células A549 , Linhagem Celular , Complexos de Coordenação/química , Células HeLa , Humanos , Lisossomos/ultraestrutura , Microscopia Confocal/métodos , Neoplasias/diagnóstico por imagem , Imagem Óptica/métodos
12.
Chem Commun (Camb) ; 55(67): 9967-9970, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31367705

RESUMO

Herein, a seesaw ratiometric (SR) probe is designed which integrates fluorescence and surface enhanced Raman scattering (SERS) technology. Fluorescence imaging enables tracking of the spatiotemporal dynamic behaviour of telomerase. Meanwhile, SERS reverse ratiometric measurement can enable sensitive detection of telomerase activity in single living cells.


Assuntos
Corantes/química , Imagem Óptica/métodos , Análise de Célula Única/métodos , Análise Espectral Raman/métodos , Telomerase/metabolismo , DNA/química , Transferência Ressonante de Energia de Fluorescência/métodos , Ouro/química , Humanos , Células MCF-7 , Nanopartículas Metálicas/química
13.
Chem Commun (Camb) ; 55(67): 10015-10018, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31378791

RESUMO

We report the first neutral and water-soluble polymer capable of strong mitochondrial targeting in vitro and in vivo, zwitterionic poly[2-(N-oxide-N,N-diethylamino)ethyl methacrylate] (OPDEA). OPDEA is quickly internalized via macropinocytosis by various cancer cells and transferred into the mitochondria, which slightly lowers the mitochondrial membrane potential as determined by the JC-1 assay.


Assuntos
Mitocôndrias/metabolismo , Ácidos Polimetacrílicos/química , Animais , Linhagem Celular Tumoral , Corantes Fluorescentes/química , Humanos , Concentração de Íons de Hidrogênio , Potencial da Membrana Mitocondrial , Camundongos , Imagem Óptica/métodos , Permeabilidade , Ácidos Polimetacrílicos/metabolismo , Solubilidade , Água
14.
Anticancer Res ; 39(8): 4065-4071, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31366489

RESUMO

BACKGROUND: Surgical orthotopic implantation of human colon cancer tissue to the ceca of mice has been used to mimic behavior of cancer in human patients for the development of precision cancer medicine. However, with the current method of serosal surface implantation (SSI) of pieces of human colon cancer tissue, cancer cells are exposed to the peritoneum, which can artificially increase the rate of peritoneal carcinomatosis (PC) during the disease course. The objective of the present study was to introduce a tumor-sealing method (TSM) and compare it with SSI for the ability to produce clinically-relevant metastases without artificial PC. MATERIALS AND METHODS: HCT116 colon cancer cells transfected with green fluorescence protein (GFP) were cultured and then injected into the subcutaneous layer of athymic nude mice. Subcutaneous tumors were allowed to grow sufficiently to supply adequate tumor for orthotopic implantation. For SSI, a 1 mm3-sized tumor fragment was sutured to partially torn serosa of the cecum. For TSM, the blind end of the cecum was folded over the tumor fragment and sealed with sutures. At 20 days after implantation, all mice were opened to visualize PC by intravital fluorescence imaging. At necropsy, distant metastasis was investigated using frozen section of whole blocks of organs. RESULTS: At 20 days after implantation, PC rates in the SSI group and the TSM group were 80% (12/15) and 20% (3/15), respectively (p<0.001). The liver metastasis rate was 41.7% (5/12) in the SSI group and 50% (5/10) in the TSM group (p=0.696). The lung metastasis rate was 0% (0/12) in the SSI group and 10% (1/10) in the TSM group (p=0.201). The mean survival of mice without PC on the 20th day was significantly longer than that of mice with PC on the 20th day (69.1±14.7 vs. 44.5±12.4 days, p=0.001). CONCLUSION: These results suggest that TSM might be a more patient-like and useful method as a model of metastatic colon cancer than SSI.


Assuntos
Carcinogênese/genética , Neoplasias do Colo/patologia , Neoplasias Hepáticas/patologia , Neoplasias Pulmonares/patologia , Animais , Neoplasias do Colo/genética , Neoplasias do Colo/cirurgia , Modelos Animais de Doenças , Proteínas de Fluorescência Verde/química , Células HCT116 , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/secundário , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/secundário , Camundongos , Metástase Neoplásica , Transplante de Neoplasias/métodos , Imagem Óptica , Neoplasias Peritoneais/genética , Neoplasias Peritoneais/patologia , Ensaios Antitumorais Modelo de Xenoenxerto
15.
Chem Commun (Camb) ; 55(72): 10740-10743, 2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31432813

RESUMO

We constructed a two-photon fluorescence ratio probe (CST) for in situ quantitative real-time detection of mitochondrial O2˙-. Fluorescence imaging showed that O2˙- was over-generated from mitochondria and conveyed to the cytoplasm via voltage-dependent anion channels in hepatic ischemia-reperfusion mice, damaging the important functional protein aconitase in the cytoplasm.


Assuntos
Fígado/metabolismo , Mitocôndrias/química , Imagem Óptica , Fótons , Traumatismo por Reperfusão/metabolismo , Superóxidos/química , Animais , Ânions/química , Ânions/metabolismo , Transporte Biológico , Corantes Fluorescentes/química , Camundongos , Mitocôndrias/metabolismo , Estrutura Molecular , Superóxidos/metabolismo
16.
Chem Commun (Camb) ; 55(72): 10768-10771, 2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31432821

RESUMO

By covalent combination of a chiral amino acid, lipid, and achiral phenothiazine derivative, a reaction-based chiroptical probe, PTZ-D, was obtained. PTZ-D could self-assemble into a chiral organogel realizing the chirality transformation from a chiral amino acid to a self-assembled system and displaying unprecedented chiroptical monitoring of ClO- with switchable CPL signals.


Assuntos
Aminoácidos/química , Ácido Hipocloroso/análise , Luminescência , Imagem Óptica , Géis/síntese química , Géis/química , Estrutura Molecular , Tamanho da Partícula
19.
Chem Commun (Camb) ; 55(71): 10615-10618, 2019 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-31428753

RESUMO

A programmable molecular beacon (MB) with a good discrimination capability for mature and precursor microRNAs was loaded onto the surface of Mo2C quantum dots (QDs) for accurate detection of intracellular mature microRNAs.


Assuntos
Corantes Fluorescentes/química , MicroRNAs/análise , Molibdênio/química , Pontos Quânticos/química , Animais , Técnicas Biossensoriais/métodos , Linhagem Celular Tumoral , Humanos , Limite de Detecção , Camundongos , Imagem Óptica/métodos , Precursores de RNA/análise , Propriedades de Superfície
20.
Chem Commun (Camb) ; 55(71): 10627-10630, 2019 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-31429450

RESUMO

We report the synthesis of a novel hydroxyl-functionalised heteroleptic bis-NHC gold(i) complex that permits conjugation to various amines via carbamate bond formation. The resulting derivatives were studied in vitro using cell proliferation assays and fluorescent microscopic imaging of human cancer cell lines.


Assuntos
Aminas/química , Antineoplásicos/síntese química , Carbamatos/química , Complexos de Coordenação/síntese química , Corantes Fluorescentes/síntese química , Ouro/química , Células A549 , Antineoplásicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Complexos de Coordenação/farmacologia , Doxorrubicina/química , Humanos , Imagem Óptica , Tiorredoxina Dissulfeto Redutase/antagonistas & inibidores , Triazóis/química
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA