Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 75
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Phytochemistry ; 177: 112429, 2020 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-32559488

RESUMO

Ellagitannins have a marked antioxidant effect and can prevent liver injury induced by free radicals. An undescribed ellagitannin named styphelioidin was isolated from Melaleuca styphelioides Sm. The structure of styphelioidin was elucidated by using various spectroscopic methods. The hepatoprotective activity of styphelioidin (25, 50, and 100 µM) was tested using the CCl4-challenged HepG2 cell model by measuring alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels in HepG2 cells treated with styphelioidin for 1 h followed by 40 mM CCl4. Glutathione (GSH), superoxide dismutase activity (SOD) and lipid peroxidation (MDA) were evaluated to determine the mechanisms of the hepatoprotective activity. Styphelioidin significantly reduced the levels of ALT, AST, and MDA at all tested concentrations. Moreover, it conferred a marked increase in the GSH levels and the SOD activity compared to the CCl4-treated groups. Styphelioidin also exerted DPPH· radical-scavenging effects with an IC50 value of 3.67 µM. Results indicated the hepatoprotective therapeutic potential of styphelioidin comparable to silymarin. Moreover, anti-inflammatory activity was assessed and styphelioidin inhibited fMLF/CB-induced elastase release in human neutrophils with IC50 2.51 µM. Cell-free experiments with human neutrophil elastase indicated a direct enzymatic inhibitory effect of styphelioidin on the enzyme activity (IC50 2.58 µM). The potential of styphelioidin to interact with human neutrophil elastase binding sites was further confirmed by molecular docking of styphelioidin into human neutrophil elastase crystal structure using AutoDock 4.2. Styphelioidin represents a potent hepatoprotective and antioxidant agent with effects on ALT, AST, MDA, GSH, and SOD comparable to silymarin. The beneficial anti-elastase properties hold the potential for drug development against elastase-related inflammatory diseases. This study highlights a promising natural hepatoprotective and anti-inflammatory candidate derived from M. styphelioides.

2.
Redox Biol ; 34: 101571, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32446175

RESUMO

Recurrence and metastasis remain the major cause of cancer mortality. Even for early-stage lung cancer, adjuvant chemotherapy yields merely slight increase to patient survival. EF-hand domain-containing protein D2 (EFHD2) has recently been implicated in recurrence of patients with stage I lung adenocarcinoma. In this study, we investigated the correlation between EFHD2 and chemoresistance in non-small cell lung cancer (NSCLC). High expression of EFHD2 was significantly associated with poor overall survival of NSCLC patients with chemotherapy in in silica analysis. Ectopic EFHD2 overexpression increased cisplatin resistance, whereas EFHD2 knockdown improved chemoresponse. Mechanistically, EFHD2 induced the production of NADPH oxidase 4 (NOX4) and in turn the increase of intracellular reactive oxygen species (ROS), consequently activating membrane expression of the ATP-binding cassette subfamily C member 1 (ABCC1) for drug efflux. Non-steroidal anti-inflammatory drug (NSAID) ibuprofen suppressed EFHD2 expression by leading to the proteasomal and lysosomal degradation of EFHD2 through a cyclooxygenase (COX)-independent mechanism. Combining ibuprofen with cisplatin enhanced antitumor responsiveness in a murine xenograft model in comparison with the individual treatment. In conclusion, we demonstrate that EFHD2 promotes chemoresistance through the NOX4-ROS-ABCC1 axis and therefore developing EFHD2-targeting strategies may offer a new avenue to improve adjuvant chemotherapy of lung cancer.

3.
Sensors (Basel) ; 20(7)2020 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-32230996

RESUMO

Cancer has been one of the leading causes of death globally, with metastases and recurrences contributing to this result. The detection of circulating tumor cells (CTCs), which have been implicated as a major population of cells that is responsible for seeding and migration of tumor sites, could contribute to early detection of metastasis and recurrences, consequently increasing the chances of cure. This review article focuses on the current progress in microfluidics technology in CTCs diagnostics, extending to the use of nanomaterials and surface modification techniques for diagnostic applications, with an emphasis on the importance of integrating microchannels, nanomaterials, and surface modification techniques in the isolating and detecting of CTCs.

4.
Cancer Immunol Immunother ; 69(8): 1493-1504, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32285170

RESUMO

Though therapy that promotes anti-tumor response about CD8+ tumor-infiltrating lymphocytes (TILs) has shown great potential, clinical responses to CD8+ TILs immunotherapy vary considerably, largely because of different subpopulation of CD8+ TILs exhibiting different biological characters. To define the relationship between subpopulation of CD8+ TILs and the outcome of antitumor reaction, the phenotype and function of CD103+ CD8+ TILs in esophageal squamous cell carcinoma (ESCC) were investigated. CD103+ CD8+ TILs were presented in ESCC, which displayed phenotype of tissue-resident memory T cells and exhibited high expression of immune checkpoints (PD-1, TIM-3). CD103+ CD8+ TILs were positively associated with the overall survivals of ESCC patients. This population of cells elicited potent proliferation and cytotoxic cytokine secretion potential. In addition, CD103+ CD8+ TILs were elicited potent anti-tumor immunity after anti-PD-1 blockade and were not affected by chemotherapy. This study emphasized the feature of CD103+ CD8+ TILs in immune response and identified potentially new targets in ESCC patients.


Assuntos
Antígenos CD/metabolismo , Linfócitos T CD8-Positivos/imunologia , Neoplasias Esofágicas/imunologia , Neoplasias Esofágicas/metabolismo , Cadeias alfa de Integrinas/metabolismo , Linfócitos do Interstício Tumoral/imunologia , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Microambiente Tumoral/imunologia , 4-Nitroquinolina-1-Óxido/toxicidade , Adulto , Idoso , Animais , Anticorpos Monoclonais/farmacologia , Antígenos CD/imunologia , Biomarcadores Tumorais , Carcinógenos/toxicidade , Estudos de Coortes , Neoplasias Esofágicas/induzido quimicamente , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/induzido quimicamente , Carcinoma de Células Escamosas do Esôfago/imunologia , Carcinoma de Células Escamosas do Esôfago/metabolismo , Carcinoma de Células Escamosas do Esôfago/patologia , Feminino , Seguimentos , Humanos , Cadeias alfa de Integrinas/imunologia , Masculino , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Prognóstico , Receptor de Morte Celular Programada 1/imunologia , Taxa de Sobrevida , Células Tumorais Cultivadas
5.
Int J Mol Sci ; 21(8)2020 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-32331417

RESUMO

Retinal prosthesis has recently emerged as a treatment strategy for retinopathies, providing excellent assistance in the treatment of age-related macular degeneration (AMD) and retinitis pigmentosa. The potential application of graphene oxide (GO), a highly biocompatible nanomaterial with superior physicochemical properties, in the fabrication of electrodes for retinal prosthesis, is reviewed in this article. This review integrates insights from biological medicine and nanotechnology, with electronic and electrical engineering technological breakthroughs, and aims to highlight innovative objectives in developing biomedical applications of retinal prosthesis.

6.
Biomed Res Int ; 2020: 8914953, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32280705

RESUMO

Background: How to effectively control the postoperative pain of patients is extremely important to clinicians. Transversus abdominis plane (TAP) block is a novel analgesic method reported to greatly decrease postoperative pain. However, in many areas, there still exists a phenomenon of surgeons using wound infiltration (WI) with conventional local anesthetics (not liposome anesthetics) as the main means to decrease postoperative pain because of traditional wisdom or convenience. Here, we compared the analgesic effectiveness of the two different methods to determine which method is more suitable for adult patients. Materials and methods. A systematic review and meta-analysis of randomized controlled trials (RCTs) comparing TAP block and WI without liposome anesthetics in adult patients were performed. Frequently used databases were extensively searched. The main outcomes were postoperative pain scores in different situations (at rest or during movement) and the time until the first use of rescue analgesics. The secondary outcomes were postoperative nausea and vomiting (PONV) incidence and patient satisfaction scores. Results: Fifteen studies with 983 participants met the inclusion criteria and were included in the present study. The heterogeneity in the final analysis regarding the pain score was low to moderate. The major results of the sensitivity analysis were stable. WI had the same analgesic effect as TAP block only at the one-hour postoperative time point (mean difference = -0.32, 95% confidence interval (-0.87, 0.24), P = 0.26) and was associated with a shorter time until the first rescue analgesic and poorer patient satisfaction. Conclusion: TAP block results in a more effective and steady analgesic effect than WI with conventional local anesthetics in adult patients from the early postoperative period and obtains higher patient satisfaction.

8.
Nanomaterials (Basel) ; 9(12)2019 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-31816919

RESUMO

Liquid biopsies use blood or urine as test samples, which are able to be continuously collected in a non-invasive manner. The analysis of cancer-related biomarkers such as circulating tumor cells (CTCs), circulating tumor DNA (ctDNA), microRNA, and exosomes provides important information in early cancer diagnosis, tumor metastasis detection, and postoperative recurrence monitoring assist with clinical diagnosis. However, low concentrations of some tumor markers, such as CTCs, ctDNA, and microRNA, in the blood limit its applications in clinical detection and analysis. Nanomaterials based on graphene oxide have good physicochemical properties and are now widely used in biomedical detection technologies. These materials have properties including good hydrophilicity, mechanical flexibility, electrical conductivity, biocompatibility, and optical performance. Moreover, utilizing graphene oxide as a biosensor interface has effectively improved the sensitivity and specificity of biosensors for cancer detection. In this review, we discuss various cancer detection technologies regarding graphene oxide and discuss the prospects and challenges of this technology.

9.
Front Cell Dev Biol ; 7: 275, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31788472

RESUMO

Current research has enabled the use of microphysiological systems and creation of models for alveolar and pulmonary diseases. However, bottlenecks remain in terms of medium- and long-term regulation of cell cultures and their functions in microchannel systems, as well as in the enhancement of in vitro representation of alveolar models and reference values of the data. Currently used systems also require on-chip manufacturing of complex units, such as pumps, tubes, and other cumbersome structures for maintaining cells in culture. In addition, system simplification and minimization of all external and human factors major challenges facing the establishment of in vitro alveolar models. In this study, a magnetically driven dynamic alveolus cell-culture system has been developed to use controlled magnetic force to drive a magnetic film on the chip, thereby directing the fluid within it to produce a circulating flow. The system has been confirmed to be conducive with regard to facilitating uniform attachment of human alveolar epithelial cells and long-term culture. The cell structure has been recapitulated, and differentiation functions have been maintained. Subsequently, reactions between silica nanoparticles and human alveolar epithelial cells have been used to validate the effects and advantages of the proposed dynamic chip-based system compared to a static environment. The innovative concept of use of a magnetic drive has been successfully employed in this study to create a simple and controllable yet dynamic alveolus cell-culture system to realize its functions and advantages with regard to in vitro tissue construction.

10.
Onco Targets Ther ; 12: 9421-9434, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31807021

RESUMO

Background: Previous studies have investigated the expression of miR-133b in non-small cell lung cancer (NSCLC); however, its underlying mechanism in relation to the pathogenesis of NSCLC remains unclear. Methods: The aim of this study was to investigate the correlation between miR-133b expression and clinical parameters based on the Cancer Genome Atlas (TCGA) and real-time quantitative real-time PCR (RT-qPCR) data. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were performed to identify the biological function of miR-133b. A protein-protein interaction (PPI) network was constructed to screen for hub genes. The Gene Expression Profiling Interaction Analysis (GEPIA) and the Human Protein Atlas databases (HPAD) were employed to validate the hub genes. The cBioPortal database was used to identify neighboring genes with alteration frequencies greater than 20% gene alterations. Results: miR-133b was downregulated in NSCLC tissues, and expression was correlated with lymph node metastasis (P < 0.05). A total of 362 genes were considered as the potential targets of miR-133b in NSCLC. These candidate target genes highly enriched in various key pathways such as the PI3K-Akt pathways, P53 signal pathways, and ECM-receptor interaction. PPI revealed 10 genes as hub genes with node degrees ≥10. Conclusion: The study validated that miR-133b is downregulated in NSCLC. In addition, miR-133b might function as a biomarker for the diagnosis and prognosis of NSCLC. Bioinformatics analysis revealed that miR-133b could be involved in NSCLC metastasis.

11.
Sci Rep ; 9(1): 19917, 2019 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-31882775

RESUMO

Circulating tumor cells (CTC) play important roles in various cancers; however, few studies have assessed their clinical utility in neuroendocrine tumors. This study aimed to prospectively evaluate the prognostic value of CTC counts in Asian patients with neuroendocrine tumors before and during anti-cancer therapy. Patients who were diagnosed with unresectable histological neuroendocrine tumors between September 2011 and September 2017 were enrolled. CTC testing was performed before and during anti-cancer therapy using a negative selection protocol. Chromogranin A levels were also assessed. Univariate and multivariate Cox's proportional hazard model with forward LR model was performed to investigate the impact of independent factors on overall survival and progression-free survival. Kaplan-Meier method with log-rank tests were used to determine the difference among different clinicopathological signatures and CTC cutoff. The baseline CTC detection rate was 94.3% (33/35). CTC counts were associated with cancer stages (I-III vs. IV, P = 0.015), liver metastasis (P = 0.026), and neuroendocrine tumor grading (P = 0.03). The median progression-free survival and overall survivals were 12.3 and 30.4 months, respectively. In multivariate Cox regression model, neuroendocrine tumors grading and baseline CTC counts were both independent prognostic factors for progression-free survival (PFS, P = 0.005 and 0.015, respectively) and overall survival (OS, P = 0.018 and 0.023, respectively). In Kaplan-Meier analysis, lower baseline chromogranin A levels were associated with longer PFS (P = 0.024). Baseline CTC counts are associated with the clinicopathologic features of neuroendocrine tumors and are an independent prognostic factor for this malignancy.

12.
Chemistry ; 25(60): 13748-13758, 2019 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-31400031

RESUMO

Solid-state light-emitting electrochemical cells (LECs) have several advantages, such as low-voltage operation, compatibility with inert metal electrodes, large-area flexible substrates, and simple solution-processable device architectures. However, most of the studies on saturated red LECs show low or moderate device efficiencies (external quantum efficiency (EQE) <3.3 %). In this work, we demonstrate a series of five red-emitting cationic iridium complexes (RED1--RED5) with 2,2'-biquinoline ligands and test their electroluminescence (EL) characteristics in LECs. The Commission Internationale de l'Eclairage (CIE) 1931 coordinates for the LECs based on these complexes are all beyond the National Television System Committee (NTSC) red standard point (0.67, 0.33). The maximal EQE of the neat-film RED1-based LECs reaches 7.4 %. The reddest complex, RED3, is doped in the blue-emitting host complex, BG, to fabricate host-guest LECs. The maximal EQE of the host-guest LECs (1 wt % complex RED3) reaches 9.4 %, which is among the highest reported for the saturated red LECs.

13.
Int J Biol Macromol ; 138: 37-48, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31295491

RESUMO

Evidence suggests that amyloid fibril mitigation/inhibition is considered a promising approach toward treating amyloid diseases. In this work, we first examined how amyloid fibrillogenesis of lysozyme was affected by BBG, a safe triphenylmethane compound with nice blood-brain-barrier-permeability, and found that shorter fibrillar species were formed in the lysozyme samples treated with BBG. Next, alterations in the features including the secondary as well as tertiary structure, extent of aggregation, and molecular distribution of lysozyme triggered by the addition of BBG were examined by various spectroscopic techniques, right-angle light scattering, dynamic light scattering, and SDS-PAGE. In addition, we have investigated how BBG affected the lysozyme fibril-induced cytotoxicity in SH-SY5Y cells. We found that a large quantity of shorter fibrillar species and more lysozyme monomers were present in the samples treated with BBG. Also, the addition of BBG rescued SH-SY5Y cells from cell death induced by amyloid fibrils of lysozyme. Finally, information about the binding sites and interacting forces involved in the BBG-lysozyme interaction was further explored using synchronous fluorescence and molecular docking approaches. Molecular docking results revealed that, apart from the hydrophobic interaction(s), hydrogen bonding, electrostatic interactions, and van der Waal forces may also be involved in the binding interaction.


Assuntos
Amiloide/química , Muramidase/química , Agregados Proteicos/efeitos dos fármacos , Corantes de Rosanilina/farmacologia , Amiloide/toxicidade , Sítios de Ligação , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Simulação de Acoplamento Molecular , Muramidase/toxicidade , Conformação Proteica
14.
Int J Mol Sci ; 20(12)2019 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-31216691

RESUMO

Graphene and its derivatives such as graphene oxide (GO) and reduced GO (rGO) offer excellent electrical, mechanical and electrochemical properties. Further, due to the presence of high surface area, and a rich oxygen and defect framework, they are able to form nanocomposites with metal/semiconductor nanoparticles, metal oxides, quantum dots and polymers. Such nanocomposites are becoming increasingly useful as electrochemical biosensing platforms. In this review, we present a brief introduction on the aforementioned graphene derivatives, and discuss their synthetic strategies and structure-property relationships important for biosensing. We then highlight different nanocomposite platforms that have been developed for electrochemical biosensing, introducing enzymatic biosensors, followed by non-enzymatic biosensors and immunosensors. Additionally, we briefly discuss their role in the emerging field of biomedical cell capture. Finally, a brief outlook on these topics is presented.


Assuntos
Técnicas Biossensoriais , Técnicas Eletroquímicas , Grafite/química , Nanocompostos/química , Grafite/síntese química , Modelos Moleculares , Conformação Molecular , Nanocompostos/ultraestrutura
15.
Mater Sci Eng C Mater Biol Appl ; 102: 85-95, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31147057

RESUMO

Bacterial infections are often treated inadequately. Sepsis, being one of its most severe forms, is a multi-layered, life-threatening syndrome induced by rampant immune responses, like cytokine storms, that leads to high morbidity and death of infected patients. Particularly, the current increment in resistant bacterial strains and the lack of creative antibiotics to counter such menace are central reasons to the worsening of the situation. To avoid the said crisis, the antimicrobial peptides (AMPs) were used to target cell wall components, such as lipopolysaccharides (LPS), seems to have the most promise. These combine the ability of broad-spectrum bactericidal activity with low potential for induction of resistance. Inhibition of cytokine storms induced by activated immune cells has been considered a feasible treatment for in sepsis. One of the therapeutic approaches widely utilized in inducing apoptosis in inflammatory cells is the use of tumor necrosis factor (TNF)-related apoptosis-inducing ligands (TRAIL), which trigger an extrinsic apoptotic pathway via death receptors. Herein, we report TRAIL encapsulated in a bactericidal polypeptide-crosslinked nanogel that suppressed Klebsiella pneumoniae infection and overactive macrophages. Of interest, nanogel and TRAIL-nanogel treatments were more toxic towards LPS-activated cells than to naïve cells in cell viability assays. Treatment with TRAIL-nanogel significantly prolonged survival in septic mice and reduced bacterial numbers in circulation. As such, TRAIL-nanogel may be promising as a therapeutic agent for treating bacteria-infected diseases.


Assuntos
Anti-Inflamatórios/uso terapêutico , Reagentes para Ligações Cruzadas/química , Klebsiella pneumoniae/efeitos dos fármacos , Peptídeos/química , Polietilenoglicóis/química , Polietilenoimina/química , Sepse/tratamento farmacológico , Ligante Indutor de Apoptose Relacionado a TNF/uso terapêutico , Animais , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Anti-Inflamatórios/farmacologia , Apoptose/efeitos dos fármacos , Citocinas/metabolismo , Humanos , Hidrodinâmica , Mediadores da Inflamação/metabolismo , Rim/efeitos dos fármacos , Rim/lesões , Rim/patologia , Klebsiella pneumoniae/crescimento & desenvolvimento , Lipopolissacarídeos/farmacologia , Pulmão/efeitos dos fármacos , Pulmão/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Nanogéis , Tamanho da Partícula , Peptídeos/síntese química , Peptídeos/farmacologia , Espectroscopia de Prótons por Ressonância Magnética , Células RAW 264.7 , Sepse/microbiologia , Sepse/patologia , Eletricidade Estática , Análise de Sobrevida
16.
Materials (Basel) ; 12(10)2019 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-31100917

RESUMO

In this study, we sought to enhance the photovoltaic performance of silicon solar cells by coating them (via the spin-on film technique) with a layer of SiO2 containing plasmonic indium-tin-oxide nanoparticles (ITO-NPs) of various concentrations. We demonstrated that the surface plasmon resonance absorption, surface morphology, and transmittance of the ITO-NPs dispersed in SiO2 layer at various concentrations (1-7 wt%). We also assessed the plasmonic scattering effects of ITO-NPs within a layer of SiO2 with and without a sub-layer of ITO in terms of optical reflectance, external quantum efficiency, and photovoltaic current-voltage under air mass (AM) 1.5G solar simulation. Compared to an uncoated reference silicon solar cell, applying a layer of SiO2 containing 3 wt% ITO-NPs improved efficiency by 17.90%, whereas applying the same layer over a sub-layer of ITO improved efficiency by 33.27%, due to the combined effects of anti-reflection and plasmonic scattering.

17.
Nanomaterials (Basel) ; 9(4)2019 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-30987307

RESUMO

Autophagy is the spontaneous degradation of intracellular proteins and organelles in response to nutrient deprivation. The phagocytosis of iron oxide nanoparticles (IONPs) results in intracellular degradation that can be exploited for use in cancer treatment. Non-invasive magnetic control has emerged as an important technology, with breakthroughs achieved in areas such as magneto-thermal therapy and drug delivery. This study aimed to regulate autophagy in mouse B-lymphoma cells (A20) through the incorporation of IONPs-quantum dots (QDs). We hypothesized that with the application of an external magnetic field after phagocytosis of IONPs-QDs, autophagy of intracellular IONPs-QDs could be regulated in a non-invasive manner and subsequently modulate the regulation of inflammatory responses. The potential of this approach as a cancer treatment method was explored. The application of IONPs and an external magnetic force enabled the non-invasive regulation of cell autophagy and modulation of the self-regulatory function of cells. The combination of non-invasive magnetic fields and nanotechnology could provide a new approach to cancer treatment.

18.
ACS Sens ; 4(4): 1023-1031, 2019 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-30892019

RESUMO

Point-of-care (POC) application for monitoring of breath ammonia (BA) in hemodialysis (HD) patients has emerged as a promising noninvasive health monitoring approach. In this context, many organic gas sensors have been reported for BA detection. However, one of the major challenges for its integration with affordable household POC application is to achieve stable performance for accuracy and high operational current at low voltage for low-cost read-out circuitry. Herein, we exploited the stability of the Donor-Acceptor polymer on the cylindrical nanopore structure to realize the sensors with a high sensitivity and stability. Then, we proposed a double active layer (DL) strategy that exploits an ultrathin layer of Poly(3-hexylthiophene-2,5-diyl) (P3HT) to serve as a work function buffer to enhance the operational current. The DL sensor exhibits a sustainable enhanced operational current of microampere level and a stable sensing response even with the presence of P3HT layer. This effect is carefully examined with different aspects, including vertical composition profile of DL configuration, lifetime testing on different sensing layer, morphological analysis, and the versatility of the DL strategy. Finally, we utilize the DL sensor to conduct a tracing of BA concentration in two HD patients before and after HD, and correlate it with the blood urea nitrogen (BUN) levels. A good correlation coefficient of 0.96 is achieved. Moreover, the feasibility of DL sensor integrated into a low-cost circuitry was also verified. The results demonstrate the potential of this DL strategy to be used to integrate organic sensor for affordable household POC devices.


Assuntos
Amônia/análise , Testes Respiratórios/métodos , Diálise Renal , Nitrogênio da Ureia Sanguínea , Humanos , Nanoporos , Testes Imediatos , Polímeros/química , Polivinil/química , Tiofenos/química , Compostos de Estanho/química
19.
Chemistry ; 25(21): 5489-5497, 2019 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-30762257

RESUMO

Solid-state near-infrared (NIR) light-emitting devices have recently received considerable attention as NIR light sources that can penetrate deep into human tissue and are suitable for bioimaging and labeling. In addition, solid-state NIR light-emitting electrochemical cells (LECs) have shown several promising advantages over NIR organic light-emitting devices (OLEDs). However, among the reported NIR LECs based on ionic transition-metal complexes (iTMCs), there is currently no iridium-based LEC that displays NIR electroluminescence (EL) peaks near to or above 800 nm. In this report we demonstrate a simple method for adjusting the energy gap between the highest-occupied molecular orbital (HOMO) and the lowest-unoccupied molecular orbital (LUMO) of iridium-based iTMCs to generate NIR emission. We describe a series of novel ionic iridium complexes with very small energy gaps, namely NIR1-NIR6, in which 2,3-diphenylbenzo[g]quinoxaline moieties mainly take charge of the HOMO energy levels and 2,2'-biquinoline, 2-(quinolin-2-yl)quinazoline, and 2,2'-bibenzo[d]thiazole moieties mainly control the LUMO energy levels. All the complexes exhibited NIR phosphorescence, with emission maxima up to 850 nm, and have been applied as components in LECs, showing a maximum external quantum efficiency (EQE) of 0.05 % in the EL devices. By using a host-guest emissive system, with the iridium complex RED as the host and the complex NIR3 or NIR6 as guest, the highest EQE of the LECs can be further enhanced to above 0.1 %.

20.
Phytomedicine ; 54: 109-119, 2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30668360

RESUMO

BACKGROUND: Phytochemical naphtho[1,2-b] furan-4,5­dione (NFD) presenting in Avicennia marina exert anti-cancer effects, but little is known regarding about DNA damage-mediated apoptosis in non-small-cell lung carcinoma (NSCLC). PURPOSE: To examine whether NFD-induced apoptosis of NSCLC cells is correlated with the induction of DNA damage, and to investigate its underlying mechanism. STUDY DESIGN: The anti-proliferative effects of NFD were assessed by MTS Assay Kit FACS assay, and in vivo nude mice xenograft assay. The DNA damage related proteins, the Bcl-2 family and pro-apoptotic factors were examined by immunofluorescence assay, q-PCR, and western blotting. The activity of NF-κB p65 in nuclear extracts was detected using a colorimetric DNA-binding ELISA assay. The inhibitory activity of topoisomerase II (TOPO II) was evaluated by molecular docking and TOPO II catalytic assay. RESULTS: NFD exerted selective cytotoxicity against NSCLC H1299, H1437 and A549 cells rather than normal lung-embryonated cells MRC-5. Remarkably, we found that NFD activated the hull marker and modulator of DNA damage repairs such as γ-H2AX, ATM, ATR, CHK1, and CHK2 probably caused by the accumulation of intracellular reactive oxygen species (ROS) and inhibition of TOPO II activity. Furthermore, the suppression of transcription factor NF-κB by NFD resulted in significantly decreased levels of pro-survival proteins including Bcl-2 family Bcl-2, Bcl-xL and Mcl-1 and the endogenous inhibitors of apoptosis XIAP and survivin in H1299 cells. Moreover, the nude mice xenograft assay further validated the suppression of H1299 growth by NFD, which is the first report for evaluating the anti-cancer effect of NFD in vivo. CONCLUSION: These findings provide a novel mechanism indicating the inhibition of TOPO II activity and NF-κB signaling by NFD, leading to DNA damage and apoptosis of NSCLC tumor cells.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Dano ao DNA/efeitos dos fármacos , DNA Topoisomerases Tipo II/metabolismo , Furanos/farmacologia , Neoplasias Pulmonares/tratamento farmacológico , Naftoquinonas/farmacologia , Proteínas de Ligação a Poli-ADP-Ribose/metabolismo , Animais , Antineoplásicos Fitogênicos/química , Apoptose/efeitos dos fármacos , Carcinoma Pulmonar de Células não Pequenas/genética , Linhagem Celular Tumoral , DNA Topoisomerases Tipo II/química , Feminino , Furanos/química , Humanos , Neoplasias Pulmonares/genética , Camundongos Nus , Simulação de Acoplamento Molecular , NF-kappa B/metabolismo , Naftoquinonas/química , Proteínas de Ligação a Poli-ADP-Ribose/antagonistas & inibidores , Proteínas de Ligação a Poli-ADP-Ribose/química , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA