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Fine particulate matter (PM2.5) harms human health and hinders normal human life. Considering the serious complexity and obvious regional characteristics of PM2.5 pollution, it is urgent to fill in the comprehensive overview of regional characteristics and interannual evolution of PM2.5. This review studied the PM2.5 pollution in six typical areas between 2014 and 2022 based on the data published by the Chinese government and nearly 120 relevant literature. We analyzed and compared the characteristics of interannual and quarterly changes of PM2.5 concentration. The Beijing-Tianjin-Hebei region (BTH), Yangtze River Delta (YRD) and Pearl River Delta (PRD) made remarkable progress in improving PM2.5 pollution, while Fenwei Plain (FWP), Sichuan Basin (SCB) and Northeast Plain (NEP) were slightly inferior mainly due to the relatively lower level of economic development. It was found that the annual average PM2.5 concentration change versus year curves in the three areas with better pollution control conditions can be merged into a smooth curve. Importantly, this can be fitted for the accurate evaluation of each area and provide reliable prediction of its future evolution. In addition, we analyzed the factors affecting the PM2.5 in each area and summarize the causes of air pollution in China. They included primary emission, secondary generation, regional transmission, as well as unfavorable air dispersion conditions. We also suggested that the PM2.5 pollution control should target specific industries and periods, and further research need to be carried out on the process of secondary production. The results provided useful assistance such as effect prediction and strategy guidance for PM2.5 pollution control in Chinese backward areas.
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Poluentes Atmosféricos , Poluição do Ar , Monitoramento Ambiental , Material Particulado , Material Particulado/análise , China , Poluição do Ar/análise , Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Melhoria de Qualidade , Tamanho da PartículaRESUMO
BACKGROUND: With the outbreak of COVID-19, it has become very important to improve biosafety measures taken by medical staff. Fewer pretreatment steps correspond to lower chances of infection. The authors established a direct injection technique to analyze levetiracetam (LEV) concentrations in human serum and studied its application in therapeutic drug monitoring. METHODS: Serum samples were prepared by hollow fiber centrifugal ultrafiltration and the filtrate was directly injected into a ultra-high performance liquid chromatography apparatus (Waters UPLC BEH C18 column: 50 × 2.1 mm, 1.7 µm) for analysis. The mobile phase consisted of acetonitrile and water (8:92) at a flow rate of 1.0 mL/min. The column temperature was maintained at 30°C. The detected wavelength was 210 nm. RESULTS: A linear relationship was obtained for LEV from 0.625 to 80 mcg/mL (r2 = 0.999). The limit of detection for the analysis of LEV was 0.125 mcg/mL. The analysis time was shortened to 4 minutes. The recovery rate of LEV based on the current method was 96.6%-100.1%, whereas the absolute recovery rate was 93.2%-96.8%. The relative SD of intraday and interday precision was <7.3%. Stability was achieved at room temperature for 24 hours after 3 freeze-thaw cycles and at -80°C for 21 days. The method was successfully applied to determine LEV concentrations in the serum of 19 patients. CONCLUSIONS: The present method is simple, accurate, and sensitive, and can improve biosafety with the direct injection technique. It is suitable for the analysis of LEV concentrations in therapeutic drug monitoring.
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Coleta de Amostras Sanguíneas/métodos , COVID-19/epidemiologia , Monitoramento de Medicamentos/métodos , Levetiracetam/sangue , Cromatografia Líquida de Alta Pressão , Humanos , Reprodutibilidade dos Testes , SARS-CoV-2 , Fatores de TempoRESUMO
The presence of reduced aminothiols, including homocysteine (Hcy), cysteine (Cys), cysteinyl-glycine (CG), and glutathione (GSH), is significantly increased in the pathological state. However, there have been no reports on the relationship between reduced aminothiols (Hcy, Cys, CG, and GSH) and different genders, ages, and drug combinations in human blood. The accurate quantification of these reduced thiols in biological fluids is important for monitoring some special pathological conditions of humans. However, the published methods typically not only require cumbersome and technically challenging processing procedures to ensure reliable measurements, but are also laborious and time-consuming, which may disturb the initial physiological balance and lead to inaccurate results. We developed a hollow fiber centrifugal ultrafiltration (HFCF-UF) method for sample preparation coupled with a high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method and used it to determine four reduced aminothiols (Hcy, Cys, CG, and GSH) in human blood for the first time. A total of 96 clinical patients were enrolled in our study. The influence of different genders, ages, and drug combinations on the levels of four reduced thiols in human blood was also discussed by SPSS 24.0. The sample preparation was simplified to a single 5 min centrifugation step in a sealed system that did not disturb the physiological environment. The validation parameters for the methodological results were excellent. The procedure was successfully applied to monitoring the concentrations of four reduced aminothiols (Hcy, Cys, CG, and GSH) in 96 clinical blood samples. There were no significant differences in Hcy, Cys, CG, or GSH for the different genders, ages, or combinations with methotrexate or vancomycin (P > 0.05). However, there was a significant increase in Hcy concentration in patients treated with valproic acid who were diagnosed with epilepsy (p=0.0007). It is advisable to measure reduced Hcy level in patients taking valproic acid. The developed HFCF-UF method was simple and accurate. It can be easily applied in clinical research to evaluate oxidative stress in further study.
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Análise Química do Sangue/métodos , Cisteína/sangue , Dipeptídeos/sangue , Glutationa/sangue , Homocisteína/sangue , Ultrafiltração/métodos , Antibacterianos/sangue , Antibacterianos/química , Cromatografia Líquida de Alta Pressão/métodos , Cisteína/química , Dipeptídeos/química , Inibidores Enzimáticos/sangue , Inibidores Enzimáticos/química , Congelamento , Glutationa/química , Homocisteína/química , Humanos , Limite de Detecção , Metotrexato/sangue , Metotrexato/química , Estrutura Molecular , Espectrometria de Massas em Tandem/métodos , Temperatura , Ácido Valproico/sangue , Ácido Valproico/química , Vancomicina/sangue , Vancomicina/químicaRESUMO
Stress-related alterations in brain-derived neurotrophic factor (BDNF) expression, a neurotrophin that plays a key role in synaptic plasticity, are believed to contribute to the pathophysiology of depression. Here, we show that in a chronic mild stress (CMS) model of depression the Gαi1 and Gαi3 subunits of heterotrimeric G proteins are down-regulated in the hippocampus, a key limbic structure associated with major depressive disorder. We provide evidence that Gαi1 and Gαi3 (Gαi1/3) are required for the activation of TrkB downstream signaling pathways. In mouse embryonic fibroblasts (MEFs) and CNS neurons, Gαi1/3 knockdown inhibited BDNF-induced tropomyosin-related kinase B (TrkB) endocytosis, adaptor protein activation, and Akt-mTORC1 and Erk-MAPK signaling. Functional studies show that Gαi1 and Gαi3 knockdown decreases the number of dendrites and dendritic spines in hippocampal neurons. In vivo, hippocampal Gαi1/3 knockdown after bilateral microinjection of lentiviral constructs containing Gαi1 and Gαi3 shRNA elicited depressive behaviors. Critically, exogenous expression of Gαi3 in the hippocampus reversed depressive behaviors in CMS mice. Similar results were observed in Gαi1/Gαi3 double-knockout mice, which exhibited severe depressive behaviors. These results demonstrate that heterotrimeric Gαi1 and Gαi3 proteins are essential for TrkB signaling and that disruption of Gαi1 or Gαi3 function could contribute to depressive behaviors.
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Fator Neurotrófico Derivado do Encéfalo/metabolismo , Depressão/metabolismo , Subunidade alfa Gi2 de Proteína de Ligação ao GTP/biossíntese , Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/biossíntese , Hipocampo/metabolismo , Animais , Dendritos/metabolismo , Dendritos/patologia , Espinhas Dendríticas/metabolismo , Espinhas Dendríticas/patologia , Depressão/patologia , Transtorno Depressivo Maior/metabolismo , Transtorno Depressivo Maior/patologia , Regulação para Baixo , Feminino , Subunidade alfa Gi2 de Proteína de Ligação ao GTP/genética , Subunidade alfa Gi2 de Proteína de Ligação ao GTP/metabolismo , Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/genética , Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/metabolismo , Camundongos , Camundongos Knockout , Neurônios/metabolismo , Neurônios/patologia , Transdução de Sinais/efeitos dos fármacos , Estresse Fisiológico/fisiologiaRESUMO
The difference of the patients bearing hepatocellular carcinoma (HCC) with and without cirrhosis at clinical level has not been completely determined. This study compared their differences in clinicopathological traits and prognostic factors for relapse-free survival (RFS) and overall survival (OS). Animal model was established to validate the result of clinical observation. As a result, 82 patients bearing HCC with no cirrhosis (HCC-NC) and 146 patients bearing HCC with cirrhosis (HCC-C) were included. HCC-NC exhibited shorter prothrombin time and higher plasma albumin than HCC-C. In HCC-NC, satellite nodule was an independent risk factor for OS, and high γ-glutamyl transpeptidase was an independent risk factor for RFS. In HCC-C, female sex was an independent risk factor for OS. Stratified analysis showed the OS and RFS of HCC-NC were better than HCC-C in conditions like without cancer embolus (in the portal vein or bile duct), without lymphadenopathy in hepatic portal, without satellite nodule and with small or high-differentiated tumor. Animal model analysis showed HCC-NC had a higher liver/body weight ratio, less tumor count and smaller max tumor volume than HCC-C. In conclusion, clinicopathological traits and risk factors influencing postoperative OS and RFS differed between patients with HCC-C and HCC-NC.
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Carcinoma Hepatocelular/patologia , Cirrose Hepática/complicações , Neoplasias Hepáticas/patologia , Recidiva Local de Neoplasia/patologia , Animais , Apoptose , Carcinoma Hepatocelular/etiologia , Carcinoma Hepatocelular/metabolismo , Proliferação de Células , Feminino , Humanos , Neoplasias Hepáticas/etiologia , Neoplasias Hepáticas/metabolismo , Masculino , Camundongos , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/etiologia , Recidiva Local de Neoplasia/metabolismo , Prognóstico , Taxa de Sobrevida , Carga Tumoral , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
In this study, we developed a novel liquid fermentation medium of Cordyceps militaris using pupa powder and wheat bran as nitrogen resources instead of the traditionally used peptone. This process not only reduced the cost by approximately 50%, but increased production by over 30%. Then, we explored a method to extract and purify cordycepin by combining hydrothermal reflux extraction with macroporous resin adsorption, which is inexpensive and suitable for the industrial production. The optimum conditions for hydrothermal reflux were extracting three times at 95 °C with 1:10 sample-to-water ratio, and the cordycepin purity with macroporous resin HPD-100 reached 95.23%.[Formula: see text].
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Cordyceps , Desoxiadenosinas , Fermentação , Estrutura MolecularRESUMO
In pathogenesis of Parkinson's disease (PD), mitochondrial dysfunction causes substantial reactive oxygen species (ROS) production and oxidative stress, leading to dopaminergic (DA) neuronal cell death. Mitochondrial toxins, including MPP+ (1-methyl-4-phenylpyridinium ion) and rotenone, induce oxidative injury in cultured DA neuronal cells. The current study tested the potential effect of SC79, a first-in-class small-molecule Akt activator, against the process. In SH-SY5Y cells and primary murine DA neurons, SC79 significantly attenuated MPP+- and rotenone-induced viability reduction, cell death, and apoptosis. SC79 activated Akt signaling in DA neuronal cells. Akt inhibition (by LY294002 and MK-2206) or CRISPR-Cas9-mediated Akt1 knockout completely abolished SC79-induced DA neuroprotection against MPP+. Further studies demonstrated that SC79 attenuated MPP+- and rotenone-induced ROS production, mitochondrial depolarization, and lipid peroxidation in SH-SY5Y cells and primary DA neurons. Moreover, upregulation of Nrf2-dependent genes (HO1 and NQO1) and Nrf2 protein stabilization were detected in SC79-treated SH-SY5Y cells and primary DA neurons. Together we show that SC79 protects DA neuronal cells from mitochondrial toxins possibly via activation of Akt-Nrf2 signaling.
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1-Metil-4-fenilpiridínio/toxicidade , Acetatos/farmacologia , Benzopiranos/farmacologia , Neurônios Dopaminérgicos/patologia , Ativadores de Enzimas/farmacologia , Fármacos Neuroprotetores/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Rotenona/toxicidade , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Neurônios Dopaminérgicos/efeitos dos fármacos , Humanos , Camundongos Endogâmicos C57BL , Neuroproteção/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacosRESUMO
BACKGROUND/AIMS: Glioma causes significant human mortalities annually. Molecularly-targeted therapy is a focus of glioma research. METHODS: Grb2-associated binding 1 (Gab1) expression and microRNA-29a-3p ("miR-29a-3p") expression in human glioma cells and tissues were tested by Western blotting assay and qRT-PCR assay. shRNA/siRNA strategy was applied to silence Gab1 in human glioma cells. miR-29a or anti-sense miR-29a construct was transfected to human glioma cells. Cell proliferation was tested by BrdU ELISA assay and cell counting assay. RESULTS: We show that expression of Gab1 was significantly elevated in human glioma tissues and cells, which correlated with downregulation of its putative microRNA: miR-29a-3p. In A172 glioma cells and primary human glioma cells, Gab1 shRNA/siRNA inhibited Akt-Erk activation and cell proliferation. Forced-expression of miR-29a-3p downregulated Gab1, inhibiting glioma cell proliferation, whereas miR-29a-3p was in-effective on cell proliferation in Gab1-silenced A172 cells. Furthermore, introduction of a 3'-untranslated region (3'-UTR) mutant Gab1 (UTR-G160A) blocked miR-29a-3p-induced inhibition on Akt signaling and A172 cell proliferation. CONCLUSIONS: miR-29a-3p downregulation leads to Gab1 upregulation to promote glioma cell proliferation.
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Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Glioma/patologia , MicroRNAs/metabolismo , Regiões 3' não Traduzidas , Proteínas Adaptadoras de Transdução de Sinal/antagonistas & inibidores , Proteínas Adaptadoras de Transdução de Sinal/genética , Antagomirs/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Regulação para Baixo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Glioma/metabolismo , Humanos , MicroRNAs/antagonistas & inibidores , MicroRNAs/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Transdução de SinaisRESUMO
Volatile oil in Chrysanthemum morifolium Ramat (C. morifolium) was extracted by the method of water vapor distillation and its chemical components was identified by gas-chromatography coupled with mass spectrometry (GC-MS). The volatile oil are evaluated for antibacterial activity against Escherichia coli, Staphylococcus aureus, Salmonella enteritids, Pseudomonas aeruginosa and Bacillus subtilis. Effects of surfactant, temperature, pH and ultraviolet light on antibacterial activity stability of volatile oil were analyzed too. Total 56 compounds were identified in C. morifolium volatile oil. The main constituents in C. morifolium volatile oil were monoterpenes and sesquiterpenes compounds, including hydrocarbons, esters, aldehydes, ketones, phenols and organic acids. α-curcumene was the most abundant volatile component (12.55%). The volatile oil showed promising antibacterial activity against 5 selected strains. The inhibitory effect on P. aeruginosa exhibited maximum inhibition zone diameter 20.43 mm, and E. coli showed 12.29 mm. The volatile oil treated with surfactant Tween 20 showed the strongest antibacterial activity, followed by Tween 80 and the SDS lowest, which showed the lowest. pH also had different effect on antibacterial activity stability of the C. morifolium volatile oil. No significant difference effect on antibacterial activity stability of volatile oil was observed with temperature and UV treatment.
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Here we reported that co-administration of docetaxel and a cell-permeable short-chain ceramide (C6) resulted in a striking increase in growth inhibition and apoptosis in primary and transformed breast cells (MCF-7 and MDA-231), which were associated with mitochondrial permeability transition pore (mPTP) opening, a significant reactive oxygen species (ROS) production and the pro-apoptotic AMP-Protein Kinase (AMPK) as well as c-Jun N-terminal kinases (JNK) activations. Contrarily, the mPTP blocker sanglifehrin A (SfA) or the ROS scavenger N-acetyl-l-cysteine (NAC) largely inhibited co-administration-induced cytotoxicity. Further, cyclosporin A (CsA), the inhibitor of cyclophilin-D (Cyp-D, the key mPTP component), as well as Cyp-D RNA silencing also suppressed breast cancer cell death by the co-treatment, while cells overexpressing Cyp-D showed hypersensitivity to docetaxel. Meanwhile, JNK and AMPK inhibition alleviated cell death induced by the co-administration in cultured breast cancer cells. Significantly, C6 ceramide plus docetaxel caused dramatic human epidermal growth factor receptor (HER)-1/-2 degradation and downstream Akt/Erk inhibition in HER-2 expressing MDA-231 cells. These in vitro findings provide confidence in support of further development of C6 ceramide as an adjunct of docetaxel for the treatment of the metastatic breast cancer.
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Antineoplásicos/farmacologia , Apoptose , Ceramidas/farmacologia , Taxoides/farmacologia , Adenilato Quinase/metabolismo , Neoplasias da Mama , Sobrevivência Celular/efeitos dos fármacos , Cisplatino/farmacologia , Docetaxel , Sinergismo Farmacológico , Receptores ErbB/metabolismo , Feminino , Células HEK293 , Humanos , Ácidos Hidroxâmicos/farmacologia , MAP Quinase Quinase 4/metabolismo , Células MCF-7 , Alvo Mecanístico do Complexo 1 de Rapamicina , Complexos Multiproteicos/metabolismo , Paclitaxel/farmacologia , Proteólise , Serina-Treonina Quinases TOR/metabolismo , VorinostatRESUMO
An automated online solid-phase extraction with restricted-access material combined with high-performance liquid chromatography and tandem mass spectrometry was developed and validated for the simultaneous quantification of vanillin and its vanillic acid metabolite in human plasma. After protein precipitation by methanol, which contained the internal standards, the supernatant of plasma samples was injected to the system, the endogenous large molecules were flushed out, and target analytes were trapped and enriched on the adsorbent, resulting in a minimization of sample complexity and ion suppression effects. Calibration curves were linear over the concentrations of 5-1000 ng/mL for vanillin and 10-5000 ng/mL for vanillic acid with a coefficient of determination >0.999 for the determined compounds. The lower limits of quantification of vanillin and vanillic acid were 5.0 and 10.0 ng/mL, respectively. The intra- and inter-run precisions expressed as the relative standard deviation were 2.6-8.6 and 3.2-10.2%, respectively, and the accuracies expressed as the relative error were in the range of -6.1 to 7.3%. Extraction recoveries of analytes were between 89.5 and 97.4%. There was no notable matrix effect for any analyte concentration. The developed method was proved to be sensitive, repeatable, and accurate for the quantification of vanillin and its vanillic acid metabolite in human plasma.
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Automação/métodos , Benzaldeídos/sangue , Cromatografia Líquida de Alta Pressão/métodos , Plasma/química , Espectrometria de Massas em Tandem/métodos , Ácido Vanílico/sangue , HumanosRESUMO
BACKGROUND: Free drug analysis is increasingly becoming popular in therapeutic drug monitoring (TDM). Centrifugal ultrafiltration (CF-UF) is the primary method to separate free drug from that of bound drug. However, the volume ratio of ultrafiltrate to sample solution (Vu/Vs) affects the accuracy of CF-UF, which highly depends on the different plasma conditions. Plasma protein concentrations in patients are different from those observed in healthy subjects, and there are also significant differences among patients with different diseases. Only very few studies have reported on the effect of protein concentration on the analysis methodology of free drug by CF-UF. METHODS: In this study, valproic acid was used as the representative drug, and plasma samples with different albumin concentrations were analyzed by CF-UF and hollow fiber centrifugal ultrafiltration (HFCF-UF). RESULTS: There was no significant difference of free drug concentrations by HFCF-UF and CF-UF when plasma albumin concentrations ranged 40-60 g/L. However, at low albumin concentrations (<40 g/L), a considerable difference was detected, and the difference was increased with the decrease of plasma albumin concentration. When the albumin concentration was as low as 10 g/L, the free drug concentration was 17.3 mcg/mL by CF-UF, whereas it was 10.2 mcg/mL by HFCF-UF. CONCLUSIONS: The accuracy of free drug measurement by CF-UF was albumin concentration dependent. However, such an effect was not observed when samples were prepared by HFCF-UF, which was more suitable for TDM of plasma samples from different patients. Therefore, this method could be readily applied to the measurement of free valproic acid plasma concentrations for TDM in patients.
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Monitoramento de Medicamentos/métodos , Albumina Sérica/metabolismo , Ultrafiltração/métodos , Ácido Valproico/farmacocinética , Adolescente , Adulto , Idoso , Centrifugação/métodos , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Adulto JovemRESUMO
A high-performance liquid chromatography method with on-line precolumn enzymatic reaction for the screening of xanthine oxidase inhibitors in natural extracts was developed. In this method, the enzymatic reaction occurred at the capillary inlet during a predetermined waiting period, after which the reaction product, uric acid, was separated and detected by liquid chromatography using ultraviolet absorption at 295 nm. Enzyme inhibition can be read out directly from the reduced peak area of uric acid in comparison to a reference chromatogram obtained in the absence of any inhibitor. In the present study, the availability of on-line precolumn enzymatic reaction with ultraviolet detection was firstly evaluated by determining the inhibitory mechanism and IC50 values of allopurinol, a commercially available positive drug. Then, the newly developed method was applied to screening of ten natural extracts from traditional Chinese medicine and as a result, the extract of Epimedium sagittatum (Sieb. et Zucc.) Maxim was found to be most positive for xanthine oxidase inhibition. The results obtained were compared with those obtained by offline enzyme assay and the effectiveness of the present method was confirmed. A rapid, low-cost, and fully automated method for xanthine oxidase inhibitor screening was proposed.
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The hydrotalcite with the properties of flame-retardant, eliminating smoke, filling and thermostability is a new kind of inorganic flame retardant. In the work, the MgAl hydrotalcite as flame retardant with Mg/Al molar ratio of 4 (MgAl-LDH) was prepared by using urea as the precipitating agent. The thermolysis behavior of the MgAl-LDH flame retardant was investigated by X-ray diffraction (XRD), fourier transform infrared spectroscopy (FT-IR) and thermogravimetry-differential scanning calorimetry (TG-DSC) as well as self deconvolution and curve-fitting analyses. Thermal phase transition of the MgAl-LDH was clarified, especially the characteristics of the hydroxyl groups (-OH) in the brucite-like layers and the changes in coordinate of the carbonate (CO3(2-)) from the interlayers. Based on thermodynamic data, thermal decomposition process was discussed. By.XRD analysis; it was found that the phase change took place when the decomposition temperature increased. The MgAl-LDH was decarbonated basically to MgAl mixed metal oxides (Mg-Al-O) at 500 °C, and impurity MgAl204 phase formed at 600 °C. According to the analyses of FT-IR, TG-DSC and curve-fitting technique, the hydroxyl groups (-OH) in the brucite-like layers possessed three the ligands such as [Al-OH-Al], [Al-OH-Mg] and [Mg-OH-Mg] modes. Dehydroxylation of the brucite-like layers based on the binding forces, where the [Mg-OH-Mg] among the three modes was the most difficult to be re- moved during the pyrolysis process. In the same way, the CO3(2-) ligands also possessed three modes such as H2O-bridged CO3(2-), monodentate and bidentate coordination modes. Based on the thermodynamic analysis, the thermodynamic properties of the hydrotalcite as flame retardant were evaluated, and the expressions of the Gibbs free energy, (ΔrGθT), as a function of temperature, were derived for the Mg8Al2 (OH)20CO3 crystal. Thermodynamic analysis showed that the removal of -OH from the brucite-like layers was spontaneous process, when the Gibbs free energy (ΔrGθT) was under zero at the temperature (T) above 228. 65 °C. The result and datum were close to the experimental result from the TG-DSC analyses, indicating that the relationship between the Gibbs free energy (ΔrGθT) and temperature (T) from thermodynamic analysis was reliable.
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Patients with age related macular degeneration (AMD) will develop vision loss in the center of the visual field. Reactive oxygen species (ROS)-mediated retinal pigment epithelium (RPE) cell apoptosis is an important contributor of AMD. In this study, we explored the pro-survival effect of α-melanocyte stimulating hormone (α-MSH) on oxidative stressed RPE cells. We found that α-MSH receptor melanocortin 1 receptor (MC1R) was functionally expressed in primary and transformed RPE cells. RPE cells were response to α-MSH stimulation. α-MSH activated Akt/mammalian target of rapamycin (mTOR) and Erk1/2 signalings in RPE cells, which were inhibited by MC1R siRNA knockdown. α-MSH protected RPE cells from hydrogen peroxide (H2O2)-induced apoptosis, an effect that was almost abolished when MC1R was depleted by siRNA. α-MSH-mediated S6K1 activation and pro-survival effect against H2O2 was inhibited by Akt inhibitors (perifosine, MK-2206 and LY294002). Further, mTOR inhibition by rapamycin, or by mTOR siRNA knockdown, diminished α-MSH's pro-survival effect in RPE cells. Thus, Akt and its downstream mTOR signaling mediates α-MSH-induced survival in RPE cells. In summary, we have identified a new α-MSH-MC1R physiologic pathway that reduces H2O2-induced RPE cell damage, and might minimize the risk of developing AMD.
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Estresse Oxidativo/fisiologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor Tipo 1 de Melanocortina/metabolismo , Epitélio Pigmentado da Retina/citologia , Epitélio Pigmentado da Retina/metabolismo , Transdução de Sinais/fisiologia , alfa-MSH/farmacologia , Animais , Linhagem Celular , Sobrevivência Celular , Humanos , Camundongos , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Epitélio Pigmentado da Retina/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacosRESUMO
BACKGROUND: Hepatocellular carcinoma (HCC), the primary liver cancer, is one of the most malignant human tumors with extremely poor prognosis. The aim of this study was to investigate the anti-cancer effect of berberine in a human hepatocellular carcinoma cell line (HepG2), and to study the underlying mechanisms by focusing on the AMP-activated protein kinase (AMPK) signaling cascade. RESULTS: We found that berberine induced both apoptotic and autophagic death of HepG2 cells, which was associated with a significant activation of AMPK and an increased expression of the inactive form of acetyl-CoA carboxylase (ACC). Inhibition of AMPK by RNA interference (RNAi) or by its inhibitor compound C suppressed berberine-induced caspase-3 cleavage, apoptosis and autophagy in HepG2 cells, while AICAR, the AMPK activator, possessed strong cytotoxic effects. In HepG2 cells, mammalian target of rapamycin complex 1 (mTORC1) activation was important for cell survival, and berberine inhibited mTORC1 via AMPK activation. CONCLUSIONS: Together, these results suggested that berberine-induced both apoptotic and autophagic death requires AMPK activation in HepG2 cells.
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BACKGROUND: Pancreatic cancer is one of the most aggressive human malignancies with a extremely low 5-year survival rate. Hence, the search for more effective anti-pancreatic cancer agents is urgent. METHODS: PaTu8988 pancreatic cancer cells were treated with different concentrations of suberoylanilide hydroxamic acid (SAHA), cell survival, proliferation, migration and vasculogenic mimicry (VM) were analyzed. Associated signaling changes were also analyzed by RT-PCR and Western blots. RESULTS: Here, we reported that SAHA, a histone deacetylase inhibitor (HDACi), exerted significant inhibitory efficiency against pancreatic cancer cell survival, proliferation, migration and VM. SAHA dose-dependently inhibited PaTu8988 pancreatic cancer cell growth with the IC-50 of 3.4 ± 0. 7 µM. Meanwhile, SAHA suppressed PaTu8988 cell cycle progression through inducing G2/M arrest, which was associated with cyclin-dependent kinase 1 (CDK-1)/cyclin-B1 degradation and p21/p27 upregulation. Further, SAHA induced both apoptotic and non-apoptotic death of PaTu8988 cells. Significantly, SAHA suppressed PaTu8988 cell in vitro migration and cell-dominant tube formation or VM, which was accompanied by semaphorin-4D (Sema-4D) and integrin-ß5 down-regulation. Our evidences showed that Akt activation might be important for Sema-4D expression in PaTu8988 cells, and SAHA-induced Sema-4D down-regulation might be associated with Akt inhibition. CONCLUSIONS: This study is among the first to report the VM formation in cultured human pancreatic cancer cells. And we provided strong evidence to suggest that SAHA executes significant anti-VM efficiency in the progressive pancreatic cancer cells. Thus, SAHA could be further investigated as a promising anti-pancreatic cancer agent.
Assuntos
Inibidores de Histona Desacetilases/administração & dosagem , Histona Desacetilases/biossíntese , Ácidos Hidroxâmicos/administração & dosagem , Neoplasias Pancreáticas/tratamento farmacológico , Apoptose/efeitos dos fármacos , Proteína Quinase CDC2/genética , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica , Histona Desacetilases/genética , Humanos , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/genética , Neovascularização Patológica/patologia , Neoplasias Pancreáticas/patologia , VorinostatRESUMO
OBJECTIVE: To establish a high-performance liquid chromatography-tandem mass spectrometry method (HPLC-MS/MS) to simultaneously determine colistin sulfate and tigecycline in human plasma. METHODS: Polymyxin B1 internal standard (20 µL) was added into 200 µL of plasma sample. The samples were treated with methanol-5% trichloroacetic acid (50:50, V/V) solution, and the protein precipitation method was adopted for post-injection analysis. The chromatographic column was a Dikma C18 (4.6 mm × 150 mm, 5 µm). For the mobile phase, 0.1% formic acid in aqueous solution was used for phase A, 0.1% formic acid in acetonitrile solution for phase B, and gradient elution was also applied. The flow rate was 0.8 mL/min, the column temperature was 40 °C, and the injection volume was 10 µL; Electrospray ionization and multiple reaction ion monitoring were adopted and scanned by the HPLC-MS/MS positive ion mode. RESULTS: The endogenous impurities in the plasma had no interference in the determination of the analytes. There existed a good linear relationship of colistin sulfate within the range of 0.1-10 µg/mL (R2 = 0.9986), with the lower limit of quantification (LLOQ) of 0.1 µg/mL. There existed a good linear relationship of tigecycline within the range of 0.05-5 µg/ mL (R2 = 0.9987), with the LLOQ of 0.05 µg/mL. The intra- and inter-day relative standard deviations of colistin sulfate and tigecycline were both less than 15%, and the accuracy was between 88.21% and 108.24%. The extraction had good stability, the extraction recovery rate was 87.75-91.22%, and the matrix effect was 99.40-105.26%. CONCLUSION: This study successfully established a method for simultaneously detecting colistin sulfate and tigecycline plasma concentrations. The method was simple, rapid, and highly sensitive and could be applied for therapeutic medication monitoring.
RESUMO
The pharmacological effects of flavonoids in Oroxylum indicum (L.) Kurz against inflammation, bacterial, and oxidation have been well-documented. Additionally, it is commonly consumed as tea. However, the in vivo mechanism of its main compounds has not been well elucidated. In this study, a highly selective and sensitive UHPLC-Q-TOF-MS method combined with Mass Spectrum-based Orthogonal Projection (MSOP) theory and four-step analytical strategy was established and validated to identify metabolites in rats following oral administration Oroxylum indicum (L.) Kurz extract. Furthermore, a sensitive LC-MS/MS method was developed and validated for the first time to analyze the pharmacokinetics of ten main flavonoids in rats. Notably, a total of 47 metabolites were identified in blood, bile, urine, and feces samples. The maximum plasma concentration (Cmax) values for oroxin A, oroxin B, baicalin, chrysin, baicalein, scutellarein, apigenin, quercetin oroxylin A and isorhamnetin were 2945.1 ± 11.23 ng/mL, 3123.9 ± 16.37 ng/mL, 130.40 ± 27.52 ng/mL, 117.20 ± 28.54 ng/mL, 64.12 ± 19.33 ng/mL, 97.22 ± 24.27 ng/mL, 145.22 ± 29.92 ng/mL, 45.19 ± 18.84 ng/mL, 67.32 ± 15.78 ng/mL and 128.44 ± 26.42 ng/mL. A double peak was observed in the drug-time curve of apigenin, due to enterohepatic recirculation. This study demonstrated that MSOP method provided more technical support for the identification of flavonoid metabolites in complex system than traditional methods.
RESUMO
Lithium metal batteries (LMBs) must have both long cycle life and calendar life to be commercially viable. However, "trial and error" methodologies remain prevalent in contemporary research endeavors to identify favorable electrolytes. Here, a guiding principle for the selection of solvents for LMBs is proposed, which aims to achieve high Coulombic efficiency while minimizing the corrosion. For the first time, this study reveals that the dipole moment and orientation of solvent molecules have significant impacts on lithium metal reversibility and corrosion. Solvents with high dipole moments are more likely to adsorb onto lithium metal surfaces, which also influence the solid electrolyte interphase. Using this principle, the use of LiNO3 is demonstrated as the sole salt in LiNi0.8Co0.1Mn0.1O2/Li cells can achieve excellent cycling stability. Overall, this work bridges the molecular structure of solvents to the reversibility and corrosion of lithium metal, and these concepts can be extended to other metal-based batteries.