Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 11 de 11
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Int J Pharm ; 660: 124349, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38885778

RESUMO

The clinical application of doxorubicin (DOX) is mainly restricted by its serious side effects, poor drug delivery efficiency, and limited immunogenic death (ICD) effect. To improve DOX-based chemotherapy and ameliorate its adverse effects, we utilized 3LL cell-derived extracellular vesicles to encapsulate DOX and sodium nitroprusside (SNP) to obtain DOX/SNP@CM, which could effectively target the tumor site by harnessing the inherent homologous targeting property of tumor cell membranes. DOX performed its role on chemotherapy, and SNP successfully respond to the intracellular GSH to continuously generate nitric oxide (NO). The in situ-produced NO upregulated the Fas expression on the tumor cell surface, thereby sensitizing the Fas/FasL pathway-mediated tumor cell apoptosis of DOX. Furthermore, NO also boosted the intratumoral infiltration of cytotoxic T cells by promoted ICD effect towards tumor cells. Importantly, the anti-tumor immunity tightly cooperated with Fas/FasL mediated tumor cell apoptosis by NO-mediated manipulation on Fas/FasL interaction, collectively making DOX/SNP@CM exert significant tumor growth inhibition with low-dose DOX. Remarkably, DOX and SNP both are widely used clinical medicines, ensuring DOX/SNP@CM a potential opportunity for future practical applications.

2.
BMC Nurs ; 23(1): 104, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38321427

RESUMO

BACKGROUND: Nursing students require improvement in their intravenous infusion therapy management skills, yet traditional training models possess deficiencies. The Teaching for Understanding (TfU) Framework can enhance the teaching-learning process and support quality education. Therefore, utilizing TfU framework for training may promote the performance of nurses. METHODS: Utilizing a non-synchronized design, 102 nurses were recruited using a convenience sampling method. Fifty-one student nurses from August 2019 to January 2021 were designated as the control group, and 51 student nurses from February 2021 to July 2022 were included as the intervention group. The control group received traditional teaching methods, while the intervention group was trained based on TfU framework. The impact was gauged through medical education environment perception, theory and practice assessments, and learning satisfaction surveys. RESULTS: After the training, there was no significant difference between the control group and the intervention group in the theory assessment. However, the practice assessment scores of the intervention group were significantly higher than those of the control group. Compared with the control group, the learning satisfaction scores of the trained nurses in the intervention group were significantly higher, exhibiting significant differences, particularly in communication ability, teamwork cooperation, summing up capability, and interest in learning improvement. Furthermore, the scores of the learning perceptions, atmosphere, social self-perceptions, and total scores of the intervention group were significantly higher. CONCLUSION: Training using TfU framework can heighten students' understanding and command over knowledge and skills, fuel their learning fervor, and enhance their communication and collaboration abilities. TfU framework should be disseminated in medical education to improve the quality of education.

3.
J Environ Manage ; 351: 119602, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38061093

RESUMO

This paper provides a comprehensive overview of research works on in-situ thermal conductive heating (TCH), including heat transfer in soil, desorption behavior of pollutants, and mass transfer mechanism within the site. Each stage influences the effectiveness of subsequent stages. Comparison of simulation and experimental results demonstrates that heat transfer and temperature rise in soil are related to the hydrogeological conditions, wells layout and pollutants contents. Thermal desorption of pollutants from soil particles can be influenced by four aspects: energy input, pollutant properties, soil characteristics, and the binding state of pollutant in soil. The exponential decay kinetic model exhibits better applicability for fitting thermal desorption processes. After desorption, the pollutants migrate in soil driven by high temperature and extraction pressure, while hydrogeological conditions of the site determine the actual migration path and rate. Applying convection-dispersion model allows for quantitatively describing the complex migration behavior of pollutants in heterogeneous sites. Future research should focus more on the composite effects of multiple factors in TCH and develop multi-field coupling models through the combination of numerical simulation and in-situ experiments. Accurate characterization and prediction of entire TCH process can improve remediation efficiency, reduce energy costs, and achieve sustainable low-carbon remediation.


Assuntos
Poluentes Ambientais , Recuperação e Remediação Ambiental , Poluentes do Solo , Solo/química , Calefação , Poluentes do Solo/química
4.
Sci Total Environ ; 807(Pt 3): 151042, 2022 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-34673074

RESUMO

The misuse of both antibiotics and plastics significantly increases the environmental pollution problems associated with these contaminants. Moreover, microplastics can adsorb other pollutants in the environment. However, the mechanisms of antibiotic adsorption by degradable and nondegradable microplastics are not completely understood. In this study, we investigated the environmental behavior of norfloxacin (NOR) using polybutylene succinate (PBS), which is a degradable microplastic, and compared it with conventional microplastics, polystyrene (PS) and polyethylene (PE). The order of adsorption capacity was PS > PBS â‰« PE. The adsorption behavior fitted well with the pseudo-second-order kinetic and Langmuir isotherm models, indicating monolayer adsorption. The process is thermodynamically endothermic and non-spontaneous and is controlled by chemical and physical mechanisms, including π-π conjugation, hydrogen bonds, ion exchange, and electrostatic interactions. The adsorption capacity of microplastics was higher when the solution pH was around the pKa value of NOR than at other pH values. Ionic strength and dissolved organic matter inhibited the adsorption process. For PS and PBS, the amount of NOR adsorbed onto MPs initially decreased and then increased with the increase of coexisting heavy metal ions. Zn2+ and Pb2+ could promote the adsorption of NOR by PE. This study reveals the interaction mechanisms between microplastics and antibiotics and provides a more comprehensive theoretical basis for an ecological environmental risk assessment of different microplastics.


Assuntos
Microplásticos , Plásticos , Adsorção , Antibacterianos , Matéria Orgânica Dissolvida , Norfloxacino , Polietileno
5.
J Cell Physiol ; 236(9): 6391-6406, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33554336

RESUMO

Breast cancer, a common malignancy for women, preferentially metastasizes to bone and obesity elevates the chance of its progression. While mechanical loading can suppress obesity and tumor-driven osteolysis, its effect on bone-metastasized obese mice has not been investigated. Here, we hypothesized that mechanical loading can lessen obesity-associated bone degradation in tumor-invaded bone by regulating the fate of bone marrow-derived cells. In this study, the effects of mechanical loading in obese mice were evaluated through X-ray imaging, histology, cytology, and molecular analyses. Tumor inoculation to the tibia elevated body fat composition, osteolytic lesions, and tibia destruction, and these pathologic changes were stimulated by the high-fat diet (HFD). However, mechanical loading markedly reduced these changes. It suppressed osteoclastogenesis by downregulating receptor activator of nuclear factor Kappa-B ligand and cathepsin K and promoted osteogenesis, which was associated with the upregulation of OPG and downregulation of C/enhancer-binding protein alpha and proliferator-activated receptor gamma for adipogenic differentiation. Furthermore, it decreased the levels of tumorigenic genes such as Rac1, MMP9, and interleukin 1ß. In summary, this study demonstrates that although a HFD aggravates bone metastases associated with breast cancer, mechanical loading significantly protected tumor-invaded bone by regulating the fate of bone marrow-derived cells. The current study suggests that mechanical loading can provide a noninvasive, palliative option for alleviating breast cancer-associated bone metastasis, in particular for obese patients.


Assuntos
Medula Óssea/patologia , Neoplasias Ósseas/secundário , Neoplasias da Mama/patologia , Microambiente Celular , Adipócitos/patologia , Adipogenia , Tecido Adiposo , Animais , Peso Corporal , Osso Esponjoso/patologia , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Camundongos Endogâmicos BALB C , Camundongos Obesos , Osteoblastos/patologia , Osteoclastos/patologia , Osteogênese , Osteólise/complicações , Osteólise/patologia , Suporte de Carga
6.
Inorg Chem ; 59(10): 6808-6814, 2020 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-32330019

RESUMO

With the trigonal linker 4,4',4″-s-triazine-2,4,6-triyltribenzoic acid as a building block, porous cobalt metal-organic frameworks (named as PCN) have been successfully prepared and directly utilized as active materials in alkaline battery-type devices. For comparison, their carbon-supported hybrids (CNFs/PCN) have also been employed as battery-type electrodes. We found that the pristine PCN displayed a better performance than the CNFs/PCN composite electrode in electrochemical cells. To further investigate their electrochemical performances, alkaline battery-supercapacitor hybrid (BSH) devices with these materials as positive electrodes and activated carbon (AC) as the negative electrode were fabricated. The results indicate that the PCN//AC BSH devices delivered a maximum energy density of 16.0 Wh kg-1 at a power density of 749 W kg-1 within the voltage range of 0-1.5 V, which are much higher than those of CNFs/PCN//AC devices (12.4 Wh kg-1 at 753 W kg-1).

7.
Talanta ; 186: 104-109, 2018 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-29784336

RESUMO

A sensitive and artful colorimetric immunosensor based on horseradish peroxidase (HRP) was designed by labelling metal-organic frameworks (Cu-MOFs) on the second antibody (Cu-MOFs@Ab2) as signal amplification for the detection of trace dibutyl phthalate (DBP). In this system, when Cu-MOFs@Ab2 was captured by antigen- primary antibody (Ab1) complex, tremendous Cu(II) will be released from Cu-MOFs in the presence of nitric acid (HNO3), and Cu(II) will be further reduced to Cu(I) after the addition of sodium ascorbate (SA), consequently, inhibiting the HRP to catalyse the colorless 3,3',5,5'-tetramethylbenzidine (TMB) into blue oxidized TMB (ox TMB). Under the optimized conditions, the limit of detection (LOD) was 1 µg L-1, which was almost 60 times lower than that using a conventional ELISA with the same antibody. In addition, our method showed good accuracy and reproducibility (recoveries of 87.73-103.4%; CV values of 1.46-5.95%) through a spike-recovery analysis. The proposed immunosensor indicated great potential for trace DBP determination from environmental and food samples.


Assuntos
Colorimetria , Dibutilftalato/análise , Poluentes Ambientais/química , Contaminação de Alimentos/análise , Peroxidase do Rábano Silvestre/química , Imunoensaio , Estruturas Metalorgânicas/química , Anticorpos/química , Anticorpos/imunologia , Cobre/química , Cobre/imunologia , Peroxidase do Rábano Silvestre/metabolismo , Estruturas Metalorgânicas/síntese química , Estruturas Metalorgânicas/imunologia , Tamanho da Partícula
8.
J Agric Food Chem ; 66(11): 2996-3002, 2018 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-28762732

RESUMO

On the basis of H2O2-mediated growth of gold nanoparticle (AuNPs), a novel plasmonic enzyme-linked immunosorbent assay (pELISA) was developed with a polyclonal antibody for the ultrasensitive simultaneous naked-eye detection of tetrabromobisphenol A bis(2-hydroxyetyl) ether (TBBPA DHEE) and tetrabromobisphenol A mono(hydroxyethyl) ether (TBBPA MHEE), one of the major derivatives and byproducts of tetrabromobisphenol A (TBBPA), respectively. In this modified indirect competitive pELISA, glucose oxidase (GOx) played an important role leading to the growth of AuNPs through a reaction between GOx and glucose to produce hydrogen peroxide (H2O2). In addition, further signal amplification was achieved via a large number of GOx molecules, which were immobilized on silica nanoparticles carrying poly brushes (SiO2@PAA) to increase the enzyme load, and the whole complex was conjugated on the second antibody. Under the optimized conditions, 10-3 µg/L TBBPA DHEE can be distinguished via the observation of a colored solution, and the limit of detection (LOD) of the method using a microplate reader reaches 3.3 × 10-4 µg/L. In contrast, the sensitivity of the method was 3 orders of magnitude higher than that using conventional colorimetric ELISA with the same antibody. Furthermore, the proposed approach showed good repeatability and reliability after a recovery test fortified with a variety of targets was performed (recoveries, 78.00-102.79%; coefficient of variation (CV), 4.38-9.87%). To our knowledge, this is the first case in which pELISA was applied for the detection of small molecules via the production of H2O2 from GOx and glucose. The method will be widely used for the investigation of TBBPA DHEE and TBBPA MHEE in real environments.


Assuntos
Ensaio de Imunoadsorção Enzimática/métodos , Retardadores de Chama/análise , Ouro/química , Bifenil Polibromatos/análise , Ensaio de Imunoadsorção Enzimática/instrumentação , Glucose Oxidase/química , Limite de Detecção , Nanopartículas Metálicas/química , Bifenil Polibromatos/química
9.
Environ Pollut ; 229: 431-438, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28622663

RESUMO

Tetrabromobisphenol A bis(2-hydroxyethyl) ether (TBBPA DHEE), as one of the TBBPA derivatives, is frequently applied as a flame retardant. To date, however, little evidence has been gathered regarding its environmental behavior and fate. This is mainly attributed to the lack of an analytical approach available to measure it. Mass spectrometry cannot determine levels of TBBPA DHEE. LC-MS could not ionize TBBPA DHEE to yield enough fragments, while GC-MS could not be applied for the analysis either, due to the thermal degradation of TBBPA DHEE. We here designed a novel hapten, then conjugated it with a carrier protein and produced a type of polyclonal antibody capable of recognizing TBBPA DHEE. Based on this approach, a sensitive and high-throughput indirect competitive enzyme-linked immunosorbent assay (ELISA) was established. The respective detection limit (LOD, based on 90% B/B0) and IC50 calculated from the standard curve were 0.702 and 9.868 ng/mL for TBBPA DHEE. And the established method showed good tolerance to various matrix interferents. Using our ELISA, we measured the concentrations of these substances from environmental water samples with no pretreatment other than filtration. We found the presence of TBBPA DHEE in environmental water samples collected in Jiangsu province, and the detected concentrations ranging from 1.5 to 7.7 ng/mL. Our proposed method here could be applied to completely and systematically investigate TBBPA DHEE and TBBPA MHEE concentrations in environmental samples.


Assuntos
Monitoramento Ambiental/métodos , Ensaio de Imunoadsorção Enzimática , Bifenil Polibromatos/análise , Poluentes Químicos da Água/análise , Cromatografia Líquida , Éteres , Retardadores de Chama/análise , Cromatografia Gasosa-Espectrometria de Massas , Limite de Detecção , Espectrometria de Massas
10.
Bioresour Technol ; 233: 191-199, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28279912

RESUMO

This study was conducted to explore enhancement of the complete autotrophic nitrogen removal over nitrite (CANON) process in a modified single-stage subsurface vertical flow constructed wetland (VSSF) with saturated zone, and nitrogen transformation pathways in the VSSF treating digested swine wastewater were investigated at four different saturated zone depths (SZDs). SZD significantly affected nitrogen transformation pathways in the VSSF throughout the experiment. As the SZD was 45cm, the CANON process was enhanced most effectively in the system owing to the notable enhancement of anammox. Correspondingly, the VSSF had the best TN removal performance [(76.74±7.30)%] and lower N2O emission flux [(3.50±0.22)mg·(m2·h)-1]. It could be concluded that autotrophic nitrogen removal via CANON process could become a primary route for nitrogen removal in the VSSF with optimized microenvironment that developed as a result of the appropriate SZD.


Assuntos
Nitrogênio/metabolismo , Animais , Processos Autotróficos , Desnitrificação , Nitritos , Suínos , Eliminação de Resíduos Líquidos , Áreas Alagadas
11.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 25(4): 412-4, 2007 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-17896506

RESUMO

OBJECTIVE: To study the change of Ca2+ density in cultured osteoclast-like cells in response to fluid shear stress. METHODS: Laser scanning confocal microscope and fluorescent probe were used to detect the free Ca2+ in osteoclast-like cells before and after undergoing fluid shear stress. The images were analyzed and compared with image software. RESULTS: At 37 degrees C the free Ca2+ in osteoclast-like cells could be labelled effectively with 10 micromol/L Fluo-3/AM. Compared with contol group, the average intensity of Ca2+ fluorescent signal in osteoclast-like cells undergoing fluid shear stress increased significantly. CONCLUSION: The Cal2+ concentration in bone-marrow derived osteoclast-like cells is sensitive to fluid shear stress, which suggests osteoclast-like cells modulate their function in response to fluid shear stress through the change of free Ca2+ concentration.


Assuntos
Medula Óssea , Osteoclastos , Compostos de Anilina , Células da Medula Óssea , Cálcio , Células Cultivadas , Estresse Mecânico , Xantenos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...