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1.
Trials ; 25(1): 254, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38605413

RESUMO

BACKGROUND AND PURPOSE: Research to date has lacked definitive evidence to determine whether mirror therapy promotes the recovery of upper extremity function after stroke. Considering that previous studies did not stratify patients based on structural retention, this may be one of the reasons for the negative results obtained in many trials. The goal evaluates the efficacy of TBMT (utilizing an innovatively designed mirror) versus standard occupational therapy for stroke patient's upper limb functionality. METHODS AND ANALYSIS: This single-center randomized controlled trial will involve 50 patients with stroke. All patients will be randomly assigned to either the task-based mirror therapy or the control group. The interventions will be performed 5 days per week for 4 weeks. The primary outcomes will be the mean change in scores on both the FMA-UE and modified Barthel Index (MBI) from baseline to 4 weeks intervention and at 12 weeks follow-up between the two groups and within groups. The other outcomes will include the Action Research Arm Test (ARAT), the Nine Hole Peg Test (9HPT), the Functional Independence Measure, and MRI. DISCUSSION: This trial will not only to establish that task-based mirror therapy (TBMT) could improve the recovery of hand function after stroke but also to explore the underlying mechanisms. We expect that this finding will clarify the brain activation and brain network mechanisms underlying the improvement of hand function with task-oriented mirror therapy and lead to new ideas for stroke hand function rehabilitation. TRIAL REGISTRATION: URL: https://www.chictr.org.cn ; Unique identifier: ChiCTR2300068855. Registered on March 1, 2023.


Assuntos
Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Humanos , Terapia de Espelho de Movimento , Hemiplegia/diagnóstico , Hemiplegia/etiologia , Recuperação de Função Fisiológica/fisiologia , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/terapia , Extremidade Superior , Reabilitação do Acidente Vascular Cerebral/métodos , Resultado do Tratamento , Ensaios Clínicos Controlados Aleatórios como Assunto
2.
Artigo em Inglês | MEDLINE | ID: mdl-38082924

RESUMO

Long-term electrocardiogram (ECG) monitoring is an important and widely-used technique in the clinic that helps with the diagnosis of possible diseases that cannot be detected in a short time monitoring. However, the clinically used electrode needs conductive gel to reduce the impedance between the skin and the electrodes, which easily causes the possibility of allergy. Moreover, as the conductive gel becomes dry, the signal's quality will decrease accordingly. In this paper, we proposed a novel adhesive Carbon Paste Electrode (CPE) to achieve convenient and long-term ECG monitoring. By comparing the time-domain waveforms, the R-R peak intervals difference, and the Signal-to-Noise Ratio (SNR) of ECG with the traditional conductive gel-based electrode (Gel) in fixed and unfixed conditions, the performance of the proposed CPE was investigated. The results showed that the CPE could achieve similar ECG monitoring both in fixed and unfixed conditions. When on Day 2, the quality acquired by Gel began to decrease while CPE was still stable, which was obvious especially in unfixed condition. The R-R peak intervals showed that on Day 2, the Gel was unreliable with some abnormal points occurring. Besides, the results of SNR and average heart rate (AHR) also confirmed that the CPE could achieve similar results as Gel on Day 1 and outperformed Gel on Day 2. It is believed that the proposed CPE opens a window of high-quality long-term ECG monitoring with more convenience.


Assuntos
Adesivos , Carbono , Projetos Piloto , Eletrocardiografia/métodos , Eletrodos
3.
Mol Plant Pathol ; 24(12): 1495-1509, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37746915

RESUMO

Chitin is a long-chain polymer of ß-1,4-linked N-acetylglucosamine that forms rigid microfibrils to maintain the hyphal form and protect it from host attacks. Chitin oligomers are first recognized by the plant receptors in the apoplast region, priming the plant's immune system. Here, seven polysaccharide deacetylases (PDAs) were identified and their activities on chitin substrates were investigated via systematic characterization of the PDA family from Fusarium graminearum. Among these PDAs, FgPDA5 was identified as an important virulence factor and was specifically expressed during pathogenesis. ΔFgpda5 compromised the pathogen's ability to infect wheat. The polysaccharide deacetylase structure of FgPDA5 is essential for the pathogenicity of F. graminearum. FgPDA5 formed a homodimer and accumulated in the plant apoplast. In addition, FgPDA5 showed a high affinity toward chitin substrates. FgPDA5-mediated deacetylation of chitin oligomers prevented activation of plant defence responses. Overall, our results identify FgPDA5 as a polysaccharide deacetylase that can prevent chitin-triggered host immunity in plant apoplast through deacetylation of chitin oligomers.


Assuntos
Quitina , Fusarium , Virulência , Plantas , Imunidade Vegetal , Doenças das Plantas
4.
Front Immunol ; 13: 936667, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36341464

RESUMO

Background: Even after complete surgical treatment or chemotherapy, Non-Small Cell Lung Cancer (NSCLC) patients are also at substantial risk for recurrence and spread trend. Therapeutic cancer vaccination could increase the anti-tumor immune response and prevent tumor relapse. This study aimed to assess the characteristics of NSCLC therapeutic vaccines registered on ClinicalTrials.gov. Methods: We conducted a cross-sectional, descriptive study of clinical trials for Non-Small Cell Lung Cancer Therapeutic Vaccines Registered on ClinicalTrials.gov (https://clinicaltrials.gov/) through March 17, 2022. Results: This study encompassed 117 registered trials included for data analysis. The number of trials was significantly correlated with a beginning year (r = 0.504, P < 0.010). Of these trials, 45.30% were completed, 12.82% were terminated, and 8.55% were withdrawn. More than half of trials (52.99%) were funded by industry, and more than half of trials (52.14%) were located in economically developed North America. Regarding study designs of these trials, 27.35% were randomized, 52.14% were single group assignment, 83.76% were without masking, 35.90% were phase 1, and more than half of the trials (56.41%) recruited less than 50 participants. The highest proportion of vaccine types was protein/peptide vaccines (41.88%). Regarding TNM staging, the highest proportion of the trials is stage III-IV (26.50%). Conclusion: The number of clinical trials about the cancer therapeutic vaccines was sustained an increase in recent years. The main characteristic of clinical trials for NSCLC therapeutic vaccines is lack of randomized control, lack of mask, and recruiting less than 50 participants. In recent years, the protein/peptide vaccines for NSCLC active immunotherapy have been well studied.


Assuntos
Vacinas Anticâncer , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/patologia , Estudos Transversais , Recidiva Local de Neoplasia/tratamento farmacológico , Vacinas Anticâncer/uso terapêutico , Vacinas de Subunidades Antigênicas/uso terapêutico
5.
Mol Plant Pathol ; 23(12): 1751-1764, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35998056

RESUMO

Fusarium head blight is a destructive disease caused by Fusarium species. Little is known about the pathogenic molecular weapons of Fusarium graminearum. The gene encoding a small secreted protein, Fg02685, in F. graminearum was found to be upregulated during wheat head infection. Knockout mutation of Fg02685 reduced the growth and development of Fusarium in wheat spikes. Transient expression of Fg02685 or recombinant protein led to plant cell death in a BAK1- and SOBIR1-independent system. Fg02685 was found to trigger plant basal immunity by increasing the deposition of callose, the accumulation of reactive oxygen species (ROS), and the expression of defence-related genes. The Fg02685 signal peptide was required for the plant's apoplast accumulation and induces cell death, indicating Fg02685 is a novel conserved pathogen-associated molecular pattern. Moreover, its homologues are widely distributed in oomycetes and fungal pathogens and induced cell death in tobacco. The conserved α-helical motif at the N-terminus was necessary for the induction of cell death. Moreover, a 32-amino-acid peptide, Fg02685 N-terminus peptide 32 (FgNP32), was essential for the induction of oxidative burst, callose deposition, and mitogen-activated protein kinase signal activation in plants. Prolonged exposure to FgNP32 enhanced the plant's resistance to Fusarium and Phytophthora. This study provides new approaches for an environment-friendly control strategy for crop diseases by applying plant immune inducers to strengthen broad-spectrum disease resistance in crops.


Assuntos
Fusarium , Fusarium/genética , Resistência à Doença , Doenças das Plantas/microbiologia , Triticum/microbiologia
6.
Front Neurosci ; 16: 900146, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35747208

RESUMO

Electrocardiogram (ECG) is a critical physiological indicator that contains abundant information about human heart activities. However, it is a kind of weak low-frequency signal, which is easy to be interfered by various noises. Therefore, wearable biosensors (WBS) technique is introduced to overcome this challenge. A flexible non-contact electrode is proposed for wearable biosensors (WBS) system, which is made up of flexible printed circuits materials, and can monitor the ECG signals during exercise for a long time. It uses the principle of capacitive coupling to obtain high-quality signals, and reduces the impact of external noise through active shielding; The results showed that the proposed non-contact electrode was equivalent to a medical wet electrode. The correlation coefficient was as high as 99.70 ± 0.30% when the subject was resting, while it was as high as 97.53 ± 1.80% during exercise. High-quality ECG could still be collected at subjects walking at 7 km/h. This study suggested that the proposed flexible non-contact electrode would be a potential tool for wearable biosensors for medical application on long-term monitoring of patients' health and provide athletes with physiological signal measurements.

7.
Sci Total Environ ; 819: 153160, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35051466

RESUMO

Organophosphate flame retardants (OPFRs) have been ubiquitously detected in dust and air which could cause damage to human health through inhalation. Currently the understanding of their adverse effects and potential mechanisms on the lung are still limited. In this study, human non-small cell lung cancer cell line NCI-H1975 was used to investigate the cytotoxicity, oxidative stress, cellular apoptosis of 9 typical OPFRs with concentrations varied from 0 to 200 µM, and their toxic mechanism associated with molecular structure was compared. After 72 h, tris(1,3-dichloro-2-propyl) phosphate (TDCIPP) displayed the highest cytotoxicity, followed by 2-ethylhexyl diphenyl phosphate (EHDPP), tris(2-butoxyethyl) phosphate (TBOEP) and tris(2-chloroisopropyl) phosphate (TCIPP), while tris(2-chloroethyl) phosphate (TCEP) and tris(2-ethylhexyl) phosphate (TEHP) exhibited the least suppression on cell viability. These results indicated that the variation of cytotoxicity on OPFRs could only be partially explained by their ester linkage. Moreover, the overexpression of intracellular reactive oxygen species (ROS), free Ca2+ and cellular apoptosis suggested that exposure to OPFRs can lead to apoptosis related to oxidative stress. Six genes associated with oxidative stress and apoptosis were upregulated dramatically compared with the control, demonstrating OPFRs induced Chop/Caspase 3-related apoptosis by activating Sod1/p53/Map3k6/Fkbp5 expression in NCI-H1975 cells. This is the first study to investigate cytotoxicity and related mechanism on commonly-used OPFRs in NCI-H1975 cells.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Retardadores de Chama , Neoplasias Pulmonares , Apoptose , Caspase 3 , Monitoramento Ambiental , Retardadores de Chama/análise , Retardadores de Chama/toxicidade , Humanos , Organofosfatos/toxicidade , Compostos Organofosforados , Estresse Oxidativo , Superóxido Dismutase-1 , Proteína Supressora de Tumor p53
8.
Annu Int Conf IEEE Eng Med Biol Soc ; 2021: 6767-6770, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34892661

RESUMO

Electrocardiography (ECG) and Electromyogram (EMG) are widely used to help physicians to diagnose various diseases. Besides, long-term physiological signals monitoring is of great significance for circumstances where certain diseases may not be observed in short-term monitoring. At present, wet electrodes are widely used in the clinic and are considered as a standard method to acquire physiological signals in high fidelity. However, current wet electrodes achieve high-quality signal acquisition by using conductive gel which will dry up as time elapses and finally leads to degradation of the signal quality. Therefore, an anhydrous viscoplastic electrode was proposed in this paper to solve the abovementioned problem. The proposed electrode, which is anhydrous and viscoplastic, enables high quality physiological signal acquisition with firm contact with the skin and it will not dry up within a long period of time. The results showed that the impedance of the proposed viscoplastic electrode could maintain relative stability after two days while that of the gel electrodes would increase significantly due to the gel dried up. Besides, the proposed electrode obtained physiological signals with high quality in both ECG and EMG tasks. After 24 hours of monitoring, the signal quality of the proposed electrode remained unchanged, indicated by the clearly recognizable time-domain signals. However, the signal waveform completely submerged in noise after the gel dried up. Moreover, the superior performance of the viscoplastic electrodes could be confirmed by the SNR difference between the two days, SNR further confirmed the superiority of the, with -2.03±2.10 dB and -3.40±8.27 dB for ECG and EMG respectively, and the SNR difference of gel electrodes were -7.59 ± 5.70 dB and -35.39±15.71 dB respectively. The proposed electrodes could be a great candidate for long-term physiological signal monitoring in risk management of healthcare.Clinical Relevance- The proposed electrode could achieve long-term physiological signals monitoring with high quality.


Assuntos
Eletrocardiografia , Eletrodos , Eletromiografia , Monitorização Fisiológica , Projetos Piloto
9.
J Hazard Mater ; 412: 125145, 2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-33516109

RESUMO

While ammonia (NH3) is one of the primary hazardous emissions from sludge aerobic composting plants, it has the potential to be recycled as an energy source or nitrogen fertilizer. Recently, an NH3 molecularly imprinted polymer (NH3-MIP) was developed that efficiently separated NH3 from other compounds, but its adsorption capacity required improvement. This study improved both NH3 adsorption capacity and separation of the NH3-MIP using acid hydrolysis optimization. NH3 adsorption capacity increased 13-fold and remained between 5.59 and 7.84 mmol·g-1 during simulated sludge aerobic composting. Separation factors for NH3/methyl sulfide (DMS) (i.e. NH3 adsorption capacity/DMS adsorption capacity) and NH3/dimethyl disulfide both increased more than 15-fold. Results showed that hydrolysis of the ester crosslinker, ethylene glycol dimethacrylate, on the NH3-MIPs produced chemical adsorption sites (‒COOH and epoxides) and increased hydrogen bonds (‒COOH and alcohol hydroxyl), which promoted NH3 adsorption and separation. It is expected that this will be a beneficial strategy for elimination of odors and NH3 recovery during sludge aerobic composting.

10.
Sensors (Basel) ; 20(19)2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-33023183

RESUMO

Inter-satellite laser communication (Is-OWC) is one of the main space optical communication technologies currently studied in various countries. In recent years, a kind of Is-OWC communication terminal without independent beacon light has appeared. Such terminals do not have a separate beacon laser with a large divergence angle, but use a narrower communication beam to complete space capture and tracking. Therefore, the energy of the light beam divided by the acquisition, tracking, and aiming (ATP) system is greatly reduced. How to perform high-precision spot position detection under extremely low signal-to-noise ratio (SNR) is a problem that must be faced. Aiming to resolve this problem, this article proposes to use a cosine signal to modulate the intensity of the signal light, so as to convert the problem of detecting a weak light signal into the problem of detecting a line spectrum signal. The authors used the time reversal convolution (TRC) algorithm with a window function to suppress noise and enhance the spectrum line, so as to accurately detect the amplitudes of the weak photocurrents. Finally, by calculating the ratio of the photocurrent amplitude values, the precise spot position is obtained. In the experiment, when the output SNR of the four-quadrant detector (QD) is as low as -17.86 dB, the proposed method can still detect the spot position and the absolute error is limited within 0.0238 mrad.

11.
Soft Matter ; 16(16): 4074, 2020 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-32270157

RESUMO

Correction for 'Preparation of electrospray ALG/PDA-PVP nanocomposites and their application in cancer therapy' by Yangjie Xu et al., Soft Matter, 2020, 16, 132-141.

12.
Bioresour Technol ; 300: 122670, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31901512

RESUMO

Ammonia (NH3) is the predominant harmful odor emitted from sludge aerobic composting plants, however, this NH3 could be recycled and used as energy or nitrogen fertilizer. Therefore, the aim of this study was to use molecular imprinting technology to prepare an adsorbent that could separate NH3 from mixed gases. An NH3 molecular imprinted polymer (NH3-MIP) was prepared by precipitation polymerization and optimal synthesis was determined by testing several different ratios of reaction components. NH3 adsorption capacity of the optimal NH3-MIP was 1.62 times that of non-imprinted material. NH3 separation factors increased from 154 (dimethyl sulfides) and 217 (dimethyl disulfides) for non-imprinted material, to 213 (dimethyl sulfides) and 302 (dimethyl disulfides) for the NH3-MIP. The adsorption mechanism was identified as physical adsorption and hydrogen bonding between H-O on the -COOH in NH3-MIP and the nitrogen in NH3. Effective desorption at 150 °C with vacuum maintained over 95% of the NH3 adsorption capacity.


Assuntos
Compostagem , Impressão Molecular , Adsorção , Amônia , Esgotos
13.
Soft Matter ; 16(1): 132-141, 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31774105

RESUMO

In this study, sodium alginate (ALG)/poly dopamine (PDA)-polyvinylpyrrolidone (PVP) nanocomposites was synthesized via a one-step electrostatic spraying method. The spinning solution of ALG and dopamine was electrostatically sprayed into an alkaline solution of PVP, calcium chloride and tris buffer (pH = 8.5), in which the gelation of ALG and the polymerization of dopamine could be simultaneously triggered. PDA hence produced possesses a high photothermal conversion efficiency, while the PVP that was facilely conjugated onto the surface of nanocomposites improves the colloidal stability and compatibility of the material. Moreover, the ALG renders the nanocomposite excellent drug (doxorubicine, DOX) loading capacity. Promisingly, the temperature increment during the PTT process could promote the DOX release, thus enhancing its therapeutic effect. The in vitro/in vivo biosafety and tumor treatment experiments further corroborate that the ALG/PDA-PVP nanocomposites have remarkable biocompatibility and synergism for tumor hyperthermia and chemotherapy. Consequently, such a one-step electrospray strategy provides a new way for designing nanomaterials and is expected to significantly promote the development of organic photothermal therapeutic agents with excellent bio-compatibility.


Assuntos
Alginatos/química , Dopamina/química , Nanocompostos/química , Neoplasias/tratamento farmacológico , Povidona/química , Animais , Antineoplásicos/química , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Materiais Biocompatíveis/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/química , Doxorrubicina/metabolismo , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Humanos , Hipertermia Induzida , Raios Infravermelhos , Camundongos , Neoplasias/patologia , Neoplasias/terapia , Fototerapia , Distribuição Tecidual
14.
Sensors (Basel) ; 19(16)2019 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-31412562

RESUMO

In the adaptive optics (AO) system, to improve the effectiveness and accuracy of wavefront sensing-less technology, a phase-based sensing approach using machine learning is proposed. In contrast to the traditional gradient-based optimization methods, the model we designed is based on an improved convolutional neural network. Specifically, the deconvolution layer, which reconstructs unknown input by measuring output, is introduced to represent the phase maps of the point spread functions at the in focus and defocus planes. The improved convolutional neural network is utilized to establish the nonlinear mapping between the input point spread functions and the corresponding phase maps of the optical system. Once well trained, the model can directly output the aberration map of the optical system with good precision. Adequate simulations and experiments are introduced to demonstrate the accuracy and real-time performance of the proposed method. The simulations show that even when atmospheric conditions D/r0 = 20, the detection root-mean-square of wavefront error of the proposed method is 0.1307 λ, which has a better accuracy than existing neural networks. When D/r0 = 15 and 10, the root-mean-square error is respectively 0.0909 λ and 0.0718 λ. It has certain applicative value in the case of medium and weak turbulence. The root-mean-square error of experiment results with D/r0 = 20 is 0.1304 λ, proving the correctness of simulations. Moreover, this method only needs 12 ms to accomplish the calculation and it has broad prospects for real-time wavefront sensing.

15.
Sensors (Basel) ; 19(17)2019 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-31450765

RESUMO

In this paper, an improved method of measuring wavefront aberration based on image with machine learning is proposed. This method had better real-time performance and higher estimation accuracy in free space optical communication in cases of strong atmospheric turbulence. We demonstrated that the network we optimized could use the point spread functions (PSFs) at a defocused plane to calculate the corresponding Zernike coefficients accurately. The computation time of the network was about 6-7 ms and the root-mean-square (RMS) wavefront error (WFE) between reconstruction and input was, on average, within 0.1263 waves in the situation of D/r0 = 20 in simulation, where D was the telescope diameter and r0 was the atmospheric coherent length. Adequate simulations and experiments were carried out to indicate the effectiveness and accuracy of the proposed method.

16.
Opt Express ; 27(11): 16058-16070, 2019 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-31163792

RESUMO

The pistons of sparse aperture systems need to be controlled within a fraction of a wavelength for the system's optimal imaging performance. In this paper, we demonstrate that deep learning is capable of performing piston sensing with a single wide-band image after appropriate training. Taking the sensing issue as a fitting task, the deep learning-based method utilizes a deep convolutional neural network to learn complex input-output mapping relations between the broadband intensity distributions and corresponding piston values. Given a trained network and one broadband focal intensity image as the input, the piston can be obtained directly and the capture range achieving the coherence length of the broadband light is available. Simulations and experiments demonstrate the validity of the proposed method. Using only in-focused broadband images as the inputs without defocus division and wavelength dispersion, obviously relaxes the optics complexity. In view of the efficiency and superiority, it's expected that the method proposed in this paper may be widely applied in multi-aperture imaging.

17.
Waste Manag ; 77: 593-602, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29907364

RESUMO

The emission of volatile sulfur compounds (VSCs) causing strong odors is a major problem in municipal sewage sludge composting plants (MSSACPs). Improving the knowledge on characteristics of VSCs emission in MSAACPs is of particular significance to elimate odors, but the studies conducted on-site to identify them are scarce. To this purpose, characteristics of VSCs emission were studied on-site from a MSSACP during different ambient temperatures corresponding with seasonal variations. Results reveal that (1) the total emission of VSCs which included methyl disulfide (DMDS), methyl sulfide (DMS), carbon disulfide, methyl mercaptan, and hydrogen sulfide (H2S) was 561.89 mg/dry kg in summer, 358.45 mg/dry kg in spring, and 215.52 mg/dry kg in winter, and the greatest amounts of VSCs were emitted during the mesophilic and pre-thermophilic phases; (2) although DMDS and DMS contributed the most towards total VSCs emissions during winter (81.93%), spring (82.55%), and summer (83.90%), their odor contributions were less than that of H2S; (3) in summer, the odor nuisance of total VSCs was higher than that in winter and spring; (4) sulfur loss in the form of VSCs emissions and total sulfur loss both increased with rising ambient temperatures during the sewage sludge aerobic composting. Results obtained in this study will be beneficial towards the elimation of odors released from MSSACPs.


Assuntos
Compostagem , Esgotos , Compostos de Enxofre/análise , Poluentes Atmosféricos , Odorantes
18.
Anticancer Drugs ; 29(4): 334-340, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29420338

RESUMO

The objective of this study was to investigate the effect and the mechanism by which curcumin reverses irinotecan-induced chemotherapy resistance in colon cancer. Construction of irinotecan-resistant colon cancer model LoVo/CPT-11R cells was performed by increasing drug concentration. The Cell Counting Kit-8 assay was used to detect inhibition of proliferation; cell morphology was observed by an optical microscope. Quantitative RT-PCR and western blotting were performed to detect molecular marker expressions during epithelial-mesenchymal transition (EMT); drug-resistant cells were treated with curcumin at different concentrations and Cell Counting Kit-8 was reperformed to detect cell proliferation after treatments. Drug-resistant cells were then divided into four groups: control group, irinotecan group, curcumin group, and irinotecan+curcumin group; quantitative RT-PCR and western blotting were performed to detect molecular marker expressions during epithelial-mesenchymal transition. Flow cytometry was used to detect cell apoptosis after grouping, and apoptosis-related protein was detected by western blotting. LoVo/CPT-11R cells could survive in culture medium containing irinotecan at 60 µg/ml and the drug-resistance index was 5.69; the drug-resistant cells had a larger volume than normal cells and were poorly connected to each other. E-cadherin expression was downregulated, whereas vimentin and N-cadherin expressions were upregulated. After curcumin treatment, drug-resistant cell proliferation was significantly inhibited; in the curcumin+irinotecan treatment group, E-cadherin expression was upregulated, whereas vimentin and N-cadherin expressions were downregulated. Curcumin could significantly increase cell apoptosis. EMT is involved in the development of irinotecan resistance and curcumin can reverse this drug resistance through reversion of the EMT process.


Assuntos
Antineoplásicos/farmacologia , Neoplasias do Colo/tratamento farmacológico , Curcumina/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Irinotecano/farmacologia , Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Caderinas/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Curcumina/uso terapêutico , Interações Medicamentosas , Transição Epitelial-Mesenquimal/fisiologia , Humanos , Irinotecano/uso terapêutico , Vimentina/metabolismo
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