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1.
Phys Chem Chem Phys ; 25(34): 22565-22582, 2023 Aug 30.
Article in English | MEDLINE | ID: mdl-37608735

ABSTRACT

In the last decade, oil-based titanium dioxide nanofluids (TiO2 NFs) have gained immense interest due to their unique insulating properties and excellent thermal performance, which endow them with the potential for application in the field of modified insulating oils. A timely comparison, analysis and summary of recent advances in the preparation, characterization, and properties of different oil-based TiO2 NFs for oil-immersed power transformers will contribute to provide a useful reference for the subsequent development of such materials. Preparation methods are reviewed along with their merits and demerits. Characterization techniques including scanning electron microscopy (SEM), transmission electron microscopy (TEM), optical microscopy (OM), X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDX), dynamic light scattering (DLS), Fourier transform infrared (FTIR) spectroscopy, thermally stimulated current (TSC), pulse electroacoustic technique (PEA), finite element analysis (FEA), fluorescence spectroscopy, Raman spectroscopy and zeta potential analysis are all applied to determine the crystal structure, particle size, surface function, surface charge and stability. Stabilization mechanisms are also discussed in detail. Some critical properties of oil-based TiO2 NFs under the application of different influencing factors such as base oils, crystal structure, size of nanoparticles, surface modifiers, mixing percentage, and aging environment are highlighted. Finally, the existing challenges and perspectives are presented for future research.

2.
Polymers (Basel) ; 15(13)2023 Jun 28.
Article in English | MEDLINE | ID: mdl-37447498

ABSTRACT

A series of epoxy resins containing various trifluoromethyl groups were synthesized and thermally cured with diaminodiphenylmethane (DDM) and aminophenyl sulfone (DDS). All epoxy resins exhibited excellent thermal stability with the glass transition temperatures of above 128 °C and 5% weight loss temperatures of above 300 °C. DDS-cured epoxy resins possessed higher thermal stability than that of DDM-cured epoxy resins, while DDM-cured epoxy resins showed better mechanical, dielectric, and hydrophobic properties. Additionally, DDM-cured epoxy resins with different locations and numbers of trifluoromethyl groups showed flexural strength in the range of 95.55~152.36 MPa, flexural modulus in the range of 1.71~2.65 GPa, dielectric constant in the range of 2.55~3.05, and water absorption in the range of 0.49~0.95%. These results indicate that the incorporation of trifluoromethyl pendant groups into epoxy resins can be a valid strategy to improve the dielectric and hydrophobic performance.

3.
J Pain Res ; 16: 1169-1183, 2023.
Article in English | MEDLINE | ID: mdl-37064955

ABSTRACT

Background and Purpose: Epidemiological studies on low back pain in residents living in mountainous areas are scarce. The study was aimed at investigating the prevalence and associated factors of low back pain in Chongqing, relatively impoverished mountainous areas of China. Materials and Methods: This was a cross-sectional study conducted at selected community or village health service centers in Chongqing over a 2-month period (May 2021 to June 2021), which included adults of Chongqing aged >18 years with or without low back pain (N=1820) chosen by stratified, cluster-sampling. Associated factors of low back pain including sociodemographic characteristics, lifestyle, and occupational features were collected, along with medical history, Oswestry Disability Questionnaire (ODI), and Numerical Rating Scale (NRS) of patients with low back pain, and carried out for at least 20 minutes per respondent. Univariate and multivariate logistic regression models were utilized for statistical analysis. Results: Overall, 30.5% of 1704 respondents presented with low back pain, with 26.3% living in flat areas and 35.6% in mountainous areas. The associated factors of low back pain were mountainous area residence (OR 1.4, 95% CI 1.1-1.8), advanced age (OR 1.8, 95% CI 1.3-2.5 for those aged 45-59 years, OR 2.3, 95% CI 1.6-3.4 for those aged 60-74 years, and OR 2.1, 95% CI 1.2-3.6 for those aged ≥75 years), married or remarried (OR 1.9, 95% CI 1.1-3.2), divorced or widowed (OR 2.7, 95% CI 14-5.4), moderate labor intensity (OR 1.4, 95% CI 1.1-1.8), frequent stoop (OR 1.6, 95% CI 1.1-2.4), and depressed mood (OR 1.6, 95% CI 1.2-2.1). Residents in the mountainous areas had a higher score on Oswestry Disability Questionnaire (8.3 [SD 6.3] vs 6.2 [SD 4.3]) than those in flat areas. Conclusion: Mountainous areas in Chongqing had higher prevalence of low back pain as 35.6%, compared with 26.3% in flat areas, with more severe dysfunction in low back pain patients. Multifactorial analysis found that the factors associated with low back pain in Chongqing residents included mountain residence, labor intensity, stoop, psychological factors and frequency of exercise.

4.
Micromachines (Basel) ; 14(2)2023 Jan 28.
Article in English | MEDLINE | ID: mdl-36838036

ABSTRACT

The neuromorphic network based on artificial neurons and synapses can solve computational difficulties, and its energy efficiency is incomparable to the traditional von Neumann architecture. As a new type of circuit component, nonvolatile memristors are very similar to biological synapses in structure and function. Only one memristor can simulate the function of a synapse. Therefore, memristors provide a new way to build hardware-based artificial neural networks. To build such an artificial neural network, in addition to the artificial synapses, artificial neurons are also needed to realize the distribution of information and the adjustment of synaptic weights. As the VO2 volatile local active memristor is complementary to nonvolatile memristors, it can be used to simulate the function of neurons. However, determining how to better realize the function of neurons with simple circuits is one of the current key problems to be solved in this field. This paper considers the influence of distribution parameters on circuit performance under the action of high-frequency and high-speed signals. Two Mott VO2 memristor units are connected and coupled with microstrip lines to simulate the Hodgkin-Huxley neuron model. It is found that the proposed memristor neuron based on microstrip lines shows the characteristics of neuron action potential: amplification and threshold.

5.
J Sci Food Agric ; 103(1): 400-410, 2023 Jan 15.
Article in English | MEDLINE | ID: mdl-36373789

ABSTRACT

BACKGROUND: Mango anthracnose is among the most severe diseases impacting mango yields and quality. While this disease can be effectively controlled through chemical means, it is vital that appropriate field efficacy and fate determination studies be conducted when applying pesticides to crops in order to appropriately gauge the ecological and health risks associated with the use of these agents. RESULTS: GAP field trials were conducted to explore the efficacy, dissipation, and terminal residues associated with the application of mefentrifluconazole and pyraclostrobin to mango crops in six locations throughout China. These analyses revealed that three applications of mefentrifluconazole [160 mg active ingredient (a.i.) kg-1 ] in combination with pyraclostrobin mixture achieved satisfactory disease control efficacy. To simultaneously detect mefentrifluconazole and pyraclostrobin residues on mangoes, a 'quick, easy, cheap, effective, rugged and safe' (QuEChERS) high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS)-based approach was established. The initial mefentrifluconazole and pyraclostrobin concentrations ranged from 0.18 to 0.34 mg kg-1 , and these two compounds exhibited respective half-lives of 5.6 to 10.8 days and 5.5 to 9.0 days. At 21 days following foliage application, the terminal mefentrifluconazole and pyraclostrobin residue concentrations were 0.02-0.04 and 0.01-0.04 mg kg-1 , with these concentrations being below the maximum residue limit (MRL) established for pyraclostrobin. Both short-term [acute reference dose percent (ARfD%) 0.78-2.36% and 2.0-6.08%] and chronic [acceptable daily intake percent (ADI%) 0.08-0.47% and 0.09-0.55%] dietary intake risk assessments for mefentrifluconazole and pyraclostrobin indicated that these terminal residue concentrations are acceptable for the general population. CONCLUSION: Mefentrifluconazole and pyraclostrobin in mango was rapidly degraded following first-order kinetics models. The dietary risk of mefentrifluconazole and pyraclostrobin through mango was negligible to consumers. The application of a 400 g L-1 mefentrifluconazole-pyraclostrobin suspension concentrate mixture represents a highly efficacious fungicidal approach to controlling mango anthracnose that exhibits significant potential for development as it is easily degraded and associated with low residual concentrations after application. © 2022 Society of Chemical Industry.


Subject(s)
Fungicides, Industrial , Mangifera , Pesticide Residues , Humans , Mangifera/metabolism , Tandem Mass Spectrometry/methods , Pesticide Residues/analysis , Fungicides, Industrial/chemistry , China , Risk Assessment
6.
Molecules ; 27(17)2022 Sep 05.
Article in English | MEDLINE | ID: mdl-36080501

ABSTRACT

This study established a QuEChERS high-performance liquid chromatography/tandem triple-quadrupole mass spectrometry method for determining azoxystrobin, pyraclostrobin, picoxystrobin, difenoconazole, chlorantraniliprole, imidacloprid, and cyantraniliprole and its metabolite (IN-J9Z38) in litchi and longan, and applied this method to the real samples. The residues in samples were extracted with acetonitrile and purified with nano-ZrO2, C18, and PSA. The samples were then detected with multireactive ion monitoring and electrospray ionization in the positive ion mode and quantified using the external matrix-matched standard method. The results showed good linearities for the eight analytes in the range of 1−100 µg/L, with correlation coefficients (r2) of >0.99. The limit of quantification was 1−10 µg/kg, and the limit of detection was 0.3−3 µg/kg. Average recovery from litchi and longan was 81−99%, with the relative standard deviation of 3.5−8.4% at fortified concentrations of 1, 10, and 100 µg/kg. The developed method is simple, rapid, efficient, and sensitive. It allowed the rapid screening, monitoring, and confirming of the aforementioned seven pesticides and a metabolite in litchi and longan.


Subject(s)
Litchi , Pesticide Residues , Pesticides , Chromatography, High Pressure Liquid , Pesticide Residues/analysis , Pesticides/analysis , Sapindaceae , Tandem Mass Spectrometry
7.
Aging (Albany NY) ; 13(8): 11411-11432, 2021 04 04.
Article in English | MEDLINE | ID: mdl-33839698

ABSTRACT

Atherosclerosis (AS)-related diseases remain among the leading causes of death worldwide. Modified Xiaoyaosan (also called Tiaogan-Liqi prescription, TGLQ), a traditional Chinese medical formulation, has been widely applied in the treatment of AS-related diseases. The aim of this study was to investigate the underlying pharmacological mechanisms of TGLQ in acting on AS. A total of 548 chemical compounds contained in TGLQ, and 969 putative targets, were collected from the Computation Platform for Integrative Pharmacology of Traditional Chinese Medicine, while 1005 therapeutic targets for the treatment of AS were obtained from the DisGeNET, TTD and CTD databases. Moreover, the 63 key targets were screened by the intersection of the targets above, and by network topological analysis. Further functional enrichment analysis showed that the key targets were significantly associated with regulation of the immune system and inflammation, improvement of lipid and glucose metabolism, regulation of the neuroendocrine system and anti-thrombosis effect. The in vivo experiments confirmed that TGLQ could reduce plasma lipid profiles and plasma inflammatory cytokines, and also inhibit AS plaque formation, within the AS model ApoE-/- mice. The in vitro experiments validated the hypothesis that TGLQ could significantly reduce intracellular lipid accumulation, suppress the production of inflammatory cytokines of macrophages induced by oxidized-LDL, and inhibit the protein expression of heat shock protein 90 and toll-like receptor 4. This study identified a list of key targets of TGLQ in the treatment of AS by applying an integrative pharmacology approach, which was validated by in vivo and in vitro experimentation.


Subject(s)
Atherosclerosis/drug therapy , Drugs, Chinese Herbal/pharmacology , Animals , Aorta/drug effects , Aorta/pathology , Atherosclerosis/blood , Atherosclerosis/immunology , Atherosclerosis/pathology , Cytokines/metabolism , Disease Models, Animal , Disease Progression , Drugs, Chinese Herbal/therapeutic use , Humans , Inflammation/blood , Inflammation/drug therapy , Inflammation/immunology , Inflammation/pathology , Lipid Metabolism/drug effects , Lipids/blood , Male , Mice , Mice, Knockout, ApoE , RAW 264.7 Cells , Rats
8.
Zhongguo Zhong Yao Za Zhi ; 45(12): 2966-2974, 2020 Jun.
Article in Chinese | MEDLINE | ID: mdl-32627474

ABSTRACT

To systematically review the efficacy and safety of Zhibitai Capsules combined with chemical drugs versus chemical drugs alone in regulating blood lipid of patients of coronary heart disease, so as to provide evidence-based reference for clinical treatment. In this study, PubMed, EMbase, Cochrane Library, China Knowledge Network Database(CNKI), Technology Journal Database(VIP) and WanFang Database(WanFang) were retrieved to find the randomized controlled trials(RCT) about therapeutic efficacy of Zhibitai Capsules combined with statins(experimental group)versus statins alone(control group)in the treatment of regulating blood lipid of patients with coronary heart disease. The retrieval time was restricted to be from the inception to October 2019. The data were extracted from the randomized controlled trials. Meta-analysis was conducted by RevMan 5.3 statistical software after quality evaluation by Cochrane 5.1.0 quality evaluation tool(blood lipid level, inflammation indicators, traditional Chinese medicine syndrome score and adverse reactions). A total of 11 RCT were included, involving 1 538 patients. The results of Meta-analysis showed that in terms of decrease of total cholesterol(MD=-0.15,95%CI[-0.25,-0.05],P=0.004), decrease of triglycerides improvement(MD=-0.16,95%CI[-0.23,-0.10],P<0.000 01), decrease of low-density lipoprotein(MD=-0.08,95%CI[-0.15,-0.01],P=0.03), and increase of high-density lipoprotein(MD=0.06,95%CI[0.03,0.10],P=0.000 2), experimental group was better than control group. At the same time, the incidence of adverse reactions were low in the experimental group(OR=0.40,95%CI[0.18,0.85],P=0.02). As a result, in treatment of coronary heart disease, the therapeutic efficacy of Zhibitai Capsules combined with statins is better than statins alone in lowering total cholesterol level, triglyceride level, low-density lipoprotein level, and increasing high-density lipoprotein level. Patients in the experimental group had a low incidence of adverse events, but the heterogeneity was slightly higher, and the result had a poor stability. However, due to the small sample size of studies included, some experimental designs were not perfect, which reduces the recommendation level and evidence intensity of this system evaluation. Therefore, high-quality multi-center, large-sample, randomized, double-blind randomized controlled trials are needed for providing more reliable basis.


Subject(s)
Coronary Disease , Drugs, Chinese Herbal , Hydroxymethylglutaryl-CoA Reductase Inhibitors , Capsules , China , Humans , Lipids
9.
Medicine (Baltimore) ; 98(51): e18375, 2019 Dec.
Article in English | MEDLINE | ID: mdl-31860998

ABSTRACT

BACKGROUND: A growing number of studies suggest that Gualou Xiebai Banxia (GLXBBX) decoction, a well-known Chinese herbal formula, has beneficial effects on eliminating angina pectoris symptoms and improving condition of stable angina pectoris (SAP) patients. However, whether this treatment is effective and safe for SAP or not, evidence supporting the effectiveness and safety of this treatment is still incomplete. Besides, there is lack of systematic review to assess the detailed situation (including risk of bias and methodology) of current related clinical studies. This study aimed to evaluate the effectiveness and safety of GLXBBX in treating SAP. METHODS: The major databases (MEDLINE, Embase, the Cochrane Library, China National Knowledge Infrastructure (CNKI), Chinese Scientific Journals Database (VIP) Database, Chinese Biomedical Database (CBM), Chinese Biomedical Literature Service System (SinoMed), and Wanfang Database) were searched from inception to March 2019. Randomized controlled trials (RCTs) of GLXBBX alone or combined with conventional drugs against conventional drugs for SAP were identified. Two assessors reviewed each trial independently. The methodological quality of the eligible studies was evaluated according to the Cochrane Collaboration's tool for assessing risk of bias. Both the data extraction and the literature quality screening evaluation were conducted independently by 2 researchers. RESULT: Totally 17 clinical RCTs were included in this study, involving 1676 patients. Due to the high probability of bias of the included studies, it was inappropriate to undertake a meta-analysis. Thus, we only conducted a systematic review and mainly discussed the methodology and limitation of the included studies. CONCLUSION: Although the current evidence prompted that GLXBBX might benefit SAP patients in improvement of angina pectoris, ECG, and blood lipid on a certain extent, this systematic review revealed no definite conclusion about the application of GLXBBX for SAP due to the poor methodological quality, high risk of bias, and inadequate reporting on clinical data. More rigorous, multicenter, sufficient-sample, and double-blind randomized clinical trials are warranted.


Subject(s)
Angina, Stable/drug therapy , Drugs, Chinese Herbal/therapeutic use , Electrocardiography , Humans , Lipids/blood , Randomized Controlled Trials as Topic
10.
BMC Cancer ; 19(1): 1159, 2019 Nov 29.
Article in English | MEDLINE | ID: mdl-31783821

ABSTRACT

BACKGROUND: Breast cancer is one of the most commonly diagnosed cancers in women, with high morbidity and mortality. Tumor metastasis is implicated in most breast cancer deaths; thus, inhibiting metastasis may provide a therapeutic direction for breast cancer. In the present study, pyropheophorbide-α methyl ester-mediated photodynamic therapy (MPPa-PDT) was used to inhibit metastasis in MCF-7 breast cancer cells. METHODS: Uptake of MPPa was detected by fluorescence microscopy. Cell viability was evaluated by the Cell Counting Kit-8 (CCK-8). ROS generation was detected by 2',7'-dichlorodihydrofluorescein diacetate (DCFH-DA). The migration of cells was assessed by wound healing assay, and invasion ability was assessed by Matrigel invasion assay. Levels of MMP2 and MMP9 were measured by PCR. Akt, phospho-Akt (Ser473), phospho-NF-κB p65 (Ser536) and NF-κB p65 were measured by western blotting. The F-actin cytoskeleton was observed by immunofluorescence. Lung tissue was visualized by hematoxylin and eosin staining. RESULTS: Following MPPa-PDT, migration and invasion were decreased in the MCF-7 cells. MPPa-PDT downregulated the expression of MMP2 and MMP9, which are responsible for the initiation of metastasis. MPPa-PDT reduced the phosphorylation of Akt and NF-κB. MPPa-PDT also reduced the expression of F-actin in cytoskeleton in MCF-7 cells. These effects were blocked by the reactive oxygen species scavenger NAC or the Akt activator SC79, while the PI3K inhibitor LY294002 or the Akt inhibitor triciribine enhanced these effects. Moreover, MPPa-PDT inhibited tumor metastasis and destroyed F-actin in vivo. CONCLUSION: Taken together, these results demonstrate that MPPa-PDT inhibits the metastasis of MCF-7 cells both in vitro and in vivo and may be involved in the Akt/NF-κB-dependent MMP-9 signaling pathway. Thus, MPPa-PDT may be a promising treatment to inhibit metastasis.


Subject(s)
Breast Neoplasms/pathology , Matrix Metalloproteinase 9/genetics , Photochemotherapy , Photosensitizing Agents/pharmacology , Porphyrins/pharmacology , Reactive Oxygen Species/metabolism , Signal Transduction/drug effects , Actins/genetics , Animals , Breast Neoplasms/drug therapy , Breast Neoplasms/metabolism , Cell Movement/drug effects , Cell Survival/drug effects , Female , Gene Expression Regulation, Neoplastic/drug effects , Humans , MCF-7 Cells , Mice, Nude , Neoplasm Invasiveness , Neoplasm Metastasis , Phosphatidylinositol 3-Kinases/metabolism , Phosphorylation , Proto-Oncogene Proteins c-akt/metabolism , Transcription Factor RelA/metabolism , Xenograft Model Antitumor Assays
11.
J Chromatogr B Analyt Technol Biomed Life Sci ; 1118-1119: 55-62, 2019 Jun 15.
Article in English | MEDLINE | ID: mdl-31029034

ABSTRACT

In this study, a coordination imprinted polymer (CIP) solid-phase extraction (SPE) method was developed to determine the residues of flumequine (FLU) in fish samples. Silanized graphene oxide-doped CIP (SGO-CIP) monolithic column was prepared using FLU-Zn2+ as template in the presence of SGO. The synthesis conditions of SGO-CIP column were optimized by the response surface methodology. Under the optimum conditions, this column showed high specificity to FLU, and the adsorption capacity reached 61.74 ng mg-1. The enrichment factor of the monolithic column was over 40-fold. Various factors affecting the extraction efficiency of SGO-CIP column during SPE were tested to achieve optimal enrichment and to reduce non-specific adsorption. FLU in fish was detected by using a high-performance liquid chromatography-fluorescence detection system. The detection limit was as low as 0.32 ng g-1 and the recovery was as high as 95.2%, with relative standard deviations of below 5.9%. This simple and sensitive method may be applicable to the determination of FLU residues in foods.


Subject(s)
Drug Residues/analysis , Fluoroquinolones/analysis , Molecular Imprinting/methods , Seafood/analysis , Solid Phase Extraction/methods , Animals , Chromatography, High Pressure Liquid/methods , Fishes , Graphite/chemistry , Limit of Detection , Linear Models , Reproducibility of Results
12.
Technol Cancer Res Treat ; 17: 1533033818785512, 2018 01 01.
Article in English | MEDLINE | ID: mdl-30068242

ABSTRACT

Photodynamic therapy is a clinically used, minimally invasive therapeutic procedure that involves the application of photosensitizers which can locate in target cells and so be irradiated at a corresponding wavelength. Laser light irradiation activation of photosensitizers generates free reactive oxygen species, which induces selective cytotoxic activity in target cells. Within recent years, aloe-emodin as a photosensitizer has been successfully applied in photodynamic therapy applications. Angiogenesis plays an important role in tumor growth and metastasis; thus, the development of a novel target treatment for angiogenesis is essential in order to improve treatment therapeutics for cancer treatment. An essential step in angiogenesis involves the formation of tube-like structures during matrix degradation, rearrangement, and apoptosis of endothelial cells. In the present study, we investigated the mechanisms of photocytotoxicity induced by aloe-emodin in human umbilical vein endothelial cells. Analysis of cell proliferation results noted a significant decrease in cultured cells which received various concentrations of aloe-emodin and photodynamic therapy-induced light doses. Additionally, mitochondrial mechanisms of apoptotic cell death were observed in aloe-emodin photodynamic therapy-treated cells, as tube formation assays noted angiogenesis suppression after treatment. The capacity of migration and invasion of human umbilical vein endothelial cells was measured using the transwell assay and demonstrated that aloe-emodin photodynamic therapy significantly inhibited the migration and invasion of human umbilical vein endothelial cells. The expression of p38, extracellular signal-regulated kinase, the c-Jun N-terminal kinases, and vascular endothelial growth factor suggested that the cellular metastasis was related to mitogen-activated protein kinase signal pathway. Furthermore, disorganization of F action cytoskeleton components was observed after aloe-emodin photodynamic therapy. Overall, the findings from this study suggest that aloe-emodin photodynamic therapy inhibited angiogenesis and cellular metastasis in human umbilical vein endothelial cells by activating the mitogen-activated protein kinase apoptotic signaling cell death pathway.


Subject(s)
Anthraquinones/pharmacology , Mitogen-Activated Protein Kinases/genetics , Neovascularization, Pathologic/drug therapy , Photochemotherapy , Apoptosis/drug effects , Cell Proliferation/drug effects , Cytoskeleton/drug effects , Gene Expression Regulation/drug effects , Human Umbilical Vein Endothelial Cells/drug effects , Humans , JNK Mitogen-Activated Protein Kinases/genetics , Neoplasm Metastasis , Neovascularization, Pathologic/genetics , Neovascularization, Pathologic/pathology , Signal Transduction/drug effects
13.
Cancer Med ; 7(5): 1908-1920, 2018 05.
Article in English | MEDLINE | ID: mdl-29577663

ABSTRACT

Autophagy and ER stress participated in the inhibition of MPPa-PDT on tumor growth, but the molecular links between them remain undefined. We just explore the molecular mechanism between them in vitro and vivo. CCK-8 assay and flow cytometer were used to detect the cytotoxicity and mode of cell death after MPPa-PDT. Furthermore, the role of autophagy was verified in MPPa-PDT. Confocal microscopy was used to show the intracellular distribution of MPPa. ER stress markers and PERK signaling pathway were detected by western blot. While in vivo, tumor histology and immunohistochemistry were performed to show the effect of MPPa-PDT in mice. After MPPa-PDT, cells viability decreased in dose-dependent manner. Besides, the cell apoptosis increased along with the increasing of Beclin-1and LC3B II but declining of P62. When pretreated with 3-MA, LC3B II formation and the cytotoxicity declined. MPPa-PDT caused increasing of ER stress markers (GRP78, CHOP) as MPPa accumulated in ER. However, pretreatment with ER stress inhibitor 4PBA, the expression of GRP78 and LC3B II was blocked but the PERK signaling pathway activated and the expression of P62 increased. In vivo, the tumor growth was significantly inhibited by MPPa-PDT. Besides, the appearance of ER stress and autophagy was further demonstrated by immunohistochemistry. Our findings demonstrate that autophagy mediated by MPPa-PDT was regulated by ER stress, via PERK signaling pathway, to kill MDA-MB-231 cells in vitro and vivo.


Subject(s)
Breast Neoplasms/drug therapy , Photochemotherapy/methods , Porphyrins/administration & dosage , eIF-2 Kinase/metabolism , Animals , Autophagy , Breast Neoplasms/metabolism , Cell Line, Tumor , Cell Proliferation/drug effects , Cell Survival/drug effects , Endoplasmic Reticulum Chaperone BiP , Endoplasmic Reticulum Stress , Female , Gene Expression Regulation, Neoplastic/drug effects , Humans , Mice , Porphyrins/pharmacology , Signal Transduction/drug effects , Xenograft Model Antitumor Assays
14.
J Pharm Biomed Anal ; 149: 258-264, 2018 Feb 05.
Article in English | MEDLINE | ID: mdl-29127907

ABSTRACT

In this study, a novel method was proposed to sensitively determine aflatoxin B1 (AFB1) in peanut sample by using a carbon quantum dots-coated dummy molecularly imprinted polymer (CDs-DMIP) monolithic column for pretreatment coupled with high performance liquid chromatography-fluorescence detection (HPLC-FLD). The CDs-DMIP monolithic column was prepared by in-situ polymerization in a water bath using 5,7-dimethoxycoumarin as dummy template molecule. The CDs-DMIP monolithic column was applied to determine AFB1 by HPLC-FLD. Satisfactory linearity was obtained over 0.5-2000ngmL-1, with a high correlation coefficient of 0.9999. The recoveries of AFB1 in peanut sample ranged from 79.5% to 91.2%, and the intraday and interday relative standard deviation ranged from 1.2% to 4.9%. Limit of detection (S/N=3) and limit of quantitation (S/N=10) were 0.118ngmL-1 and 0.393ngmL-1, respectively. Under the optimized conditions, the enrichment factor was over 71-fold. AFB1 in peanut sample and even some other samples could be sensitively determined by CDs-DMIP-HPLC-FLD method.


Subject(s)
Aflatoxin B1/analysis , Arachis/chemistry , Food Contamination/analysis , Poisons/analysis , Solid Phase Extraction/methods , Aflatoxin B1/chemistry , Aflatoxin B1/toxicity , Arachis/toxicity , Carbon/chemistry , Chromatography, High Pressure Liquid/instrumentation , Chromatography, High Pressure Liquid/methods , Coumarins/chemistry , Fluorescence , Food Contamination/prevention & control , Methacrylates/chemistry , Microscopy, Electron, Scanning , Molecular Imprinting/methods , Nitriles/chemistry , Poisons/chemistry , Poisons/toxicity , Polymers/chemistry , Quantum Dots/chemistry , Sensitivity and Specificity , Spectroscopy, Fourier Transform Infrared
15.
Oncol Lett ; 13(5): 3431-3436, 2017 May.
Article in English | MEDLINE | ID: mdl-28521449

ABSTRACT

The aim of the present study was to explore the effect of aloe-emodin (AE)-induced photodynamic activity in human gastric cancer cells. AE was used as a photosensitizer to explore the effect of photodynamic therapy (PDT) in human gastric cancer cells (SGC-7901). An MTT assay was used to detect the effect of AE-induced PDT in optimal concentrations and illumination energy densities in human gastric cancer cells. Following AE-induced PDT, morphological changes of the cells and the rate of cell death were evaluated by TUNEL assay and flow cytometry, respectively. The expression levels of caspase-9 and caspase-3 were determined by western blot analysis. The AE and AE-induced PDT demonstrated a significant inhibitive effect on the proliferation of human gastric cancer cells in dose-dependent and energy-dependent manners. For subsequent experiments, 10 µM AE and 12.8 J/cm2 illumination energy density were used. Typical morphological changes of apoptosis were observed in the cells using a TUNEL assay 12 h subsequent to AE-induced PDT. The percentage of apoptotic cells treated with AE-induced PDT significantly increased when compared with the control group, the 10 µM AE group and the illumination group (P<0.05). Upregulation of caspase-9 and caspase-3 protein levels was also observed following AE-induced PDT. The present study revealed that 10 µM AE-induced PDT had an inhibitory effect on human gastric cancer cells, and it may induce cell apoptosis by upregulating caspase-9 and caspase-3, which indicated that the mitochondrial pathway may be involved. AE-induced PDT has the potential to be a novel therapy for the treatment of human gastric cancer. However, further investigations are required.

16.
Lasers Surg Med ; 49(7): 719-726, 2017 09.
Article in English | MEDLINE | ID: mdl-28370217

ABSTRACT

BACKGROUND AND OBJECTIVE: To study the mechanisms of human glioblastoma cell resistance to methyl ester pyropheophorbide-a-mediated photodynamic therapy (MPPa-PDT) and the relationship between the cells and adenosine triphosphate-binding cassette superfamily G member 2 (ABCG2). STUDY DESIGN/MATERIALS AND METHODS: The sensitivity of four human glioma cell lines (U87, A172, SHG-44, and U251) to MPPa-PDT was detected with a CCK-8 assay. Cell apoptosis, intracellular MPPa, and singlet oxygen were tested with flow cytometry. The mRNA and protein expression of ATP-binding cassette transporters (ABCG2, MRP1, and MDR1) were detected by PCR and Western blot, respectively. RESULTS: Both the sensitivity to MPPa-PDT and intracellular MPPa in A172 were the lowest among the four cell lines, while expression of ABCG2 mRNA and protein in A172 were the highest. The intracellular MPPa and ROS in A172 receiving MPPa-PDT significantly increased after using the ABCG2 inhibitor fumitremorgin C (FTC). Both cell viability and apoptosis in A172 cells undergoing MPPa-PDT were significantly improved with FTC. CONCLUSIONS: ABCG2 plays a significant role in the resistance of A172 to MPPa-PDT. Lasers Surg. Med. 49:719-726, 2017. © 2017 Wiley Periodicals, Inc.


Subject(s)
ATP Binding Cassette Transporter, Subfamily G, Member 2/antagonists & inhibitors , Drug Resistance, Neoplasm/physiology , Glioma/drug therapy , Neoplasm Proteins/antagonists & inhibitors , Photochemotherapy/methods , Photosensitizing Agents/therapeutic use , Porphyrins/therapeutic use , ATP Binding Cassette Transporter, Subfamily G, Member 2/metabolism , Apoptosis/drug effects , Biomarkers/metabolism , Blotting, Western , Cell Line, Tumor , Cell Survival/drug effects , Glioblastoma/drug therapy , Glioblastoma/metabolism , Glioma/metabolism , Humans , Neoplasm Proteins/metabolism , Photosensitizing Agents/pharmacology , Porphyrins/pharmacology , Random Allocation , Real-Time Polymerase Chain Reaction
17.
Cancer Med ; 5(2): 361-9, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26686868

ABSTRACT

Gastric carcinoma (GC) has high incidence and mortality rates in China. Surgery and chemotherapy are the main treatments. Photodynamic therapy (PDT) has become a new treatment modality, appearing in recent experimental studies and clinical trials in various tumors. This study explores the combined effect of gene transfection with PDT on GC cells using aloe emodin (AE)-encapsulated nanoliposomes, which acted as gene carrier as well as one photosensitizer (PS). AE-encapsulated nanoliposomes (nano-AE) were prepared by reverse evaporation method. Electron microscopy and nano-ZS90 analyzer were used to detect its morphology, size, and wavelength. Western blot was used to detect the expression of the caspase-3 after transfection. MTT assay and flow cytometry were employed to determine the cytotoxic and apoptotic rates, respectively. Hoechst 33342 staining was adopted to detect the morphological changes in death gastric cancer cells. Cellular reactive oxygen species (ROS) contents were measured by DCFH-DA staining. Outcomes demonstrated that the nano-AE has good properties as gene delivery carriers as well as a PS. The group in which the recombinant plasmid of r-caspase-3 was transfected had higher protein expression of the caspase-3 than controls, meanwhile the proliferation rates of the transfected cells were inhibited by the nano-AE-mediated PDT in an energy-dependent manner. In addition, in the transfected cells, the death rate increased to 77.3% as assessed 12 h after PDT (6.4 J/cm(2) ). Hochest 33342 staining also revealed that the death rate increased significantly in the transfected group compared with other groups. Compared to control groups, the production of ROS in nano-AE PDT group had quadrupled in SGC-7901 cells as early as 1 h after PDT, while it is similar to the group of nano-AE transfection and PDT. Nano-AE-mediated r-caspase-3 gene transfection coupled with PDT could inhibit the proliferation rate and increase the apoptotic rate remarkably in human gastric cancer cells.


Subject(s)
Anthraquinones/administration & dosage , Caspase 3/genetics , Drug Compounding , Liposomes , Nanocomposites , Photochemotherapy , Stomach Neoplasms/genetics , Apoptosis/drug effects , Cell Line, Tumor , Humans , Light , Liposomes/chemistry , Nanocomposites/chemistry , Nanocomposites/ultrastructure , Particle Size , Reactive Oxygen Species/metabolism , Stomach Neoplasms/drug therapy , Stomach Neoplasms/metabolism , Transfection
18.
Article in English | MEDLINE | ID: mdl-25254055

ABSTRACT

Objectives. To evaluate the comparative analgesia effectiveness and safety of postoperative continuous femoral nerve block (CFNB) with patient controlled intravenous analgesia (PCIA) and their impact on knee function and chronic postoperative pain. Methods. Participants were randomly allocated to receive postoperative continuous femoral nerve block (group CFNB) or intravenous patient controlled analgesia (group PCIA). Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores for knee and incidence of chronic postoperative pain at 3, 6, and 12 months postoperatively were compared. postoperative pain and salvage medication at rest or during mobilization 24 hours, 48 hours, and 7 days postoperatively were also recorded. Results. After discharge from the hospital and rehabilitation of joint function, patients in group CFNB reported significantly improved knee flexion and less incidence of chronic postoperative pain at 3 months and 6 months postoperatively (P < 0.05). Analgesic rescue medications were significantly reduced in patients receiving CFNB (P < 0.001 and P = 0.031, resp.). Conclusion. With standardized rehabilitation therapy, continuous femoral nerve block analgesia reduced the incidence of chronic postoperative pain, improved motility of replaced joints, and reduced the dosages of rescue analgesic medications, suggesting a recovery-enhancing effect of peripheral nerve block analgesia.

19.
Se Pu ; 31(2): 170-3, 2013 Feb.
Article in Chinese | MEDLINE | ID: mdl-23697184

ABSTRACT

A dispersive solid phase extraction-high performance liquid chromatographic (HPLC) method was established for the simultaneous determination of 2,4-D, thiabendazole, 2-naphthol, o-phenyl phenol, diphenyl ether and biphenyl in the fruits and vegetables. The samples were vortexed for extraction with acetonitrile containing sodium chloride and anhydrous magnesium sulfate. The acetonitrile extraction was purified by acidic alumina dispersed solid phase extraction. The analysis was performed on an Agilent TC C18 column (250 mm x 4.6 mm, 5 microm) and an ultraviolet detector at 235 nm with a mobile phase of methanol-0.02 mol/L (pH 6) potassium dihydrogen phosphate solution, at a flow rate of 1.0 mL/min with gradient elution. Good linearities were observed in the range of 0.5-20 mg/L with correlation coefficients greater than 0.99. The average recoveries of the six preservatives in fruits and vegetables were in the range of 84.2% -99. 1% at three spiked levels of 1, 2 and 10 mg/kg (n = 6) and the relative standard deviations (RSDs) were in the range of 1.67%-10.3%. The limits of quantification were 1 mg/kg. This method is simple, accurate and suitable for the determination of the six preservatives in fruits and vegetables.


Subject(s)
Chromatography, High Pressure Liquid/methods , Food Preservatives/analysis , Fruit/chemistry , Solid Phase Microextraction/methods , Vegetables/chemistry , Biphenyl Compounds/analysis , Food Contamination/analysis , Naphthols/analysis , Phenols/analysis , Phenyl Ethers/analysis
20.
Rheumatol Int ; 32(12): 3771-7, 2012 Dec.
Article in English | MEDLINE | ID: mdl-22167163

ABSTRACT

Recent studies have shown a positive correlation between the degree of severity of OA and the number of apoptotic chondrocytes. The purpose of our study was to determine the effect of therapeutic ultrasound on apoptosis in articular cartilage of rabbits with knee osteoarthritis (KOA). Thirty 3-month New Zealand White rabbits were randomizingly divided into three groups, 10 in each group. Two groups underwent anterior cruciate ligament transaction in the right knee and another group left intact. Six weeks later, one group of the operated rabbits (OA-US) underwent ultrasound therapy (300 mW/cm(2), 1 MHz, 20% duty cycle, 10 min each day) for 2 weeks, while the other two groups (OA-Control and Normal Control) left untreated. Eight weeks after transection, all animals were killed. Microscopic morphologic grading was made for histological assessment. The caspases expressions and chondrocytes apoptosis were tested using the immunohistochemistry and TUNEL assessment, respectively. The mean grading of OA-US group was significantly higher than Normal Control group (P = 0.002), but significantly lower than OA-Control group (P = 0.002). Percentage of apoptosis and the optic density of cells expressing caspase-3 and caspase-8 in the three groups showed no statistical significances. Therapeutic ultrasound (300 mW/cm(2), 1 MHz, and 20% duty cycle) could relieve the degree of severity of induced KOA, while it had no effect on apoptosis and the expression of caspase-3 and caspase-8. These findings may provide a certain support for therapeutic ultrasound as an effective access to managing KOA.


Subject(s)
Apoptosis/physiology , Arthritis, Experimental/therapy , Caspase 3/metabolism , Caspase 8/metabolism , Chondrocytes/pathology , Osteoarthritis, Knee/therapy , Ultrasonic Therapy , Animals , Arthritis, Experimental/metabolism , Arthritis, Experimental/pathology , Cartilage, Articular/metabolism , Cartilage, Articular/pathology , Chondrocytes/metabolism , Female , Male , Osteoarthritis, Knee/metabolism , Osteoarthritis, Knee/pathology , Rabbits , Treatment Outcome
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