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1.
ACS Appl Mater Interfaces ; 12(19): 21748-21760, 2020 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-32294381

RESUMO

Cost-effective nitrogen-doped monolithic hierarchical carbon cryogels with excellent mechanical properties and carbon dioxide (CO2) adsorption performance were prepared from phenol, melamine, and formaldehyde (PMF) by the sol-gel, freeze-drying, and then, pyrolysis processes under an inert atmosphere. The morphology, mechanical properties, pore structure, and chemical characteristics of these cryogels were investigated. The results showed that the dilution ratio played a crucial role in the preparation of nitrogen-doped PMF carbon cryogels with controlled structures. The prepared carbon cryogels were a kind of monolithic materials composed of a hierarchical pore structure and had high compression properties (0.67 and 9.4 MPa for strength and modulus), porosity (97.6%), surface area (1406 m2/g), and heteroatom nitrogen content (0.98-2.09%). CO2 adsorption capacities up to 5.75 mmol/g at 0 °C and 4.50 mmol/g at 25 °C under 1 bar were obtained, which is at a high level among N-doped carbon materials and far better than resorcinol-based carbon gels reported. These superior CO2 adsorption capacities, high isosteric adsorption heat (Qst), and good CO2/N2 adsorption selectivity were ascribed to the synergistic effect of high surface area, appropriate pore size, and also heteroatom doping.

2.
J Pharm Biomed Anal ; 166: 30-39, 2019 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-30599279

RESUMO

Diabetic nephropathy (DN) is one of the leading causes of death in diabetes mellitus (DM). Early warning and therapy has significant clinical value for DN. This research sought to find biomarkers to predict the occurrence and development of DN and the intervention of Ginkgo biloba leaves extract (GBE) by quantifying fatty acids, amino acids, and nucleosides and nucleobases in rat plasma. Samples were respectively collected at the weekend of 5-10 weeks after diabetic rats induced by streptozotocin were defined. Plasma fasting blood-glucose, kidney index, blood urea nitrogen, creatinine, urine albumin excretion and ultrastructural morphology of kidney were measured or observed. Fatty acids, amino acids and nucleosides and nucleobases in rat plasma were analyzed by gas chromatography or liquid phase chromatography and mass spectrometry, respectively. From the biochemical index and morphological change of kidney, the rats from the 5th to 7th week were in the stage of DM while from the begin of 8th week the rats were suggested in the early stage of DN. The results of quantitative metabolomics showed that 16 differential metabolites were related to the progression of DN, and oleic acid, glutamate and guanosine might be the potential biomarkers of kidney injury. 14 differential metabolites were related to GBE against the progression of DN, while oleic acid and glutamate might be the potential biomarkers of GBE against kidney injury. Those findings potentially promote the understanding of the pathogenic progression of DN and reveal the therapeutic mechanism of GBE against DN.


Assuntos
Aminoácidos/sangue , Nefropatias Diabéticas/sangue , Ácidos Graxos/sangue , Metabolômica , Nucleosídeos/sangue , Extratos Vegetais/uso terapêutico , Albuminúria , Animais , Biomarcadores/sangue , Glicemia/metabolismo , Nitrogênio da Ureia Sanguínea , Creatinina/sangue , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/patologia , Nefropatias Diabéticas/complicações , Nefropatias Diabéticas/tratamento farmacológico , Ginkgo biloba , Rim/patologia , Rim/ultraestrutura , Masculino , Ratos
3.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 40(1): 41-51, 2018 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-29532780

RESUMO

Objective To compare the efficacy and safety of tacrolimus with those of cyclosporine in treating idiopathic membranous nephropathy (IMN) via network meta-analysis. Methods Databases including PubMed,Embase,CENTRAL (Cochrane),Wanfang Database,CNKI,and VIP citation database were searched for relevant studies according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Package Meta 4.5.0 and Gemtc 0.8.1 in R 3.3.1 were used to analyze the included studies. Results In this network meta-analysis,the complete remission rate (RR=0.98,95% CI:0.70-1.40)and the total remission rate (RR=1.00,95% CI:0.90-1.20)of idiopathic membranous nephropathy did not differ significantly between IMN patients treated with cyclosporine A or tacrolimusand,nor did the incidences of hepatic dysfunction(RR=1.40,95% CI:0.52-4.00),infection(RR=0.75,95% CI:0.18-3.10),or gastrointestinal syndrome(RR=2.1,95% CI:0.36-28.00). Conclusion Cyclosporine A seems to have similar effectiveness and safety to tacrolimus in treating IMN.


Assuntos
Ciclosporina/uso terapêutico , Glomerulonefrite Membranosa/tratamento farmacológico , Imunossupressores/uso terapêutico , Metanálise em Rede , Tacrolimo/uso terapêutico , Humanos
4.
Artigo em Inglês | MEDLINE | ID: mdl-26113453

RESUMO

The mesangial cell (MC) cultured with high glucose has been used to observe the protective effect of Ginkgo biloba extract (GBE) against diabetic nephropathy (DN), but the compounds interacting with cell are still unknown, which may be potential bioactive components. Based on this, the determination of GBE in MC lysates was proposed by high performance liquid chromatography tandem mass spectrometry (LC-MS/MS) in this study. The MC was cultured with normal or high glucose with GBE for 4, 8, 12, 16, 24 and 48h. The harvested cell was extracted with 40% acetic acid in water and further analyzed by LC-MS/MS. All the validation data including linearity, intra-day and inter-day precision, limit of detection and quantification, matrix effect, and stability were within the required limits. The validated method was successfully applied to quantify 11 compounds of GBE in cell lysates. The results showed that high glucose prolonged the peak time of all observed 11 compounds and peak concentrations of bilobalide, ginkgolide C, ginkgolide B, quercetin, luteolin, kaempferol, isorhamnetin and genkwanin in cell lysates, which hinted that these compounds may be the potential bioactive components of GBE with preventive effect against DN.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Ginkgo biloba/química , Células Mesangiais/metabolismo , Extratos Vegetais/análise , Extratos Vegetais/metabolismo , Espectrometria de Massas em Tandem/métodos , Técnicas de Cultura de Células , Nefropatias Diabéticas , Glucose/metabolismo , Humanos , Reprodutibilidade dos Testes
5.
Biomed Chromatogr ; 29(12): 1819-25, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26018907

RESUMO

A novel UPLC-DAD method was developed and validated for the simultaneous determination of baicalin (baicalein-7-glucuronide, BG), oroxylin A-7-O-glucuronide (OAG) and wogonoside (WG) in rat plasma using rutin as the internal standard. Plasma samples were precipitated using acetonitrile containing 0.1% formic acid. Separation was performed on an Agilent Eclipse Plus C18 column (2.1 × 50 mm, 1.8 µm) using gradient acetonitrile and 0.2% formic acid water solution as mobile phase. The flow-rate was set at 0.4 mL/min and the eluate was detected at 275 nm. The method was linear over the ranges of 0.075-17.50, 0.050-12.60 and 0.056-14.10 µg/mL for BG, OAG and WG, respectively. The intra- and inter-day precisions were respectively <4.8% and 6.4%. All of the limits of detection of three analytes in rat plasma were 0.01 µg/mL, whereas the limits of quantification were, respectively, 0.035, 0.025 and, 0.025 µg/mL. This assay has been successfully applied to pharmacokinetics of BG, OAG and WG in rats after oral administration of Yinhuang granule (YHG) and comparative pharmacokinetics of BG in rats following oral administration of the pure BG, Radix Scutellariae (RS) or YHG. We speculate that some co-existing ingredients in RS or YHG may increase the absorption and elimination of BG in rat. This work may be helpful for the quality control of Yinhuang granule.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Flavonoides/sangue , Flavonoides/farmacocinética , Administração Oral , Animais , Medicamentos de Ervas Chinesas/administração & dosagem , Flavonoides/química , Limite de Detecção , Modelos Lineares , Masculino , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Scutellaria baicalensis
6.
Anal Bioanal Chem ; 407(14): 4143-53, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25855151

RESUMO

The quantitative analysis of taurine and edaravone in biological sample is critical in pharmaceutical studies. Although each of them can be individually analyzed by different approaches, concurrent quantification is still a highly challenging task with respect to their great polarity variation and the complex composition of tissue sample. In the present study, to simultaneously determine taurine and edaravone in rat tissue, the sample preparation and chromatographic separation conditions were evaluated and discussed in detail. As for the sample preparation, four kinds of solvent and the volume ratio of the optimal solvent to biological sample were both tested and evaluated based on the chromatographic profile, extraction recovery, and matrix effect (ME). The chromatographic separation was performed in a reverse phase (RP) and two hydrophilic interaction liquid chromatography (HILIC) modes, and the corresponding separation efficiencies were assessed using chromatographic parameters like half-width (W 1/2 ), tailing factor (f t), theoretical plates number (N), and ME. Furthermore, adopted composition of two mobile phase systems and the concentrations of the additives in the optimum buffer system were also investigated on an Atlantis HILIC silica column according to the resultant chromatographic profiles and peak areas of the analytes. The optimal results were obtained when the biological samples were deproteined by 4-fold volume of methanol/acetonitrile (1:3, v/v) and separated on a HILIC column with a gradient elution of acetonitrile/water containing 0.2 % formic acid and 10 mM ammonium formate. The proposed approach was validated and successfully applied to the parallel determination of the tissue distribution of edaravone and taurine in rat tissues.


Assuntos
Antipirina/análogos & derivados , Cromatografia Líquida/métodos , Espectrometria de Massas em Tandem/métodos , Taurina/química , Animais , Antipirina/química , Química Encefálica , Edaravone , Rim/química , Fígado/química , Miocárdio/química , Ratos , Baço/química
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