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1.
Aging (Albany NY) ; 11(13): 4463-4477, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31326963

RESUMO

T helper 17 (Th17) cells are regarded as key factors in the pathogenesis of multiple sclerosis (MS). Although the involvement of certain microRNAs (miRNAs) in the development of MS has been reported, their roles in Th17 cell differentiation and MS pathogenesis remain elusive. In this study, we identified that let-7f-5p expression is significantly downregulated in CD4+ T cells from MS patients and during the process of Th17 differentiation. The overexpression of let-7f-5p suppressed Th17 differentiation, whereas the knockdown of let-7f-5p expression enhanced this progress. We then explored the molecular mechanism through which let-7f-5p suppressed Th17 differentiation and identified signal transducer and activator of transcription 3 (STAT3), a pivotal transcription factor of Th17 cells, as a direct target of let-7f-5p. In contrast to the downregulated expression of let-7f-5p, STAT3 and p-STAT3 protein levels were dramatically upregulated and inversely correlated with let-7f-5p in peripheral blood CD4+ T cells from MS patients. In conclusion, let-7f-5p functions as a potential inhibitor of Th17 differentiation in the pathogenesis of MS by targeting STAT3 and may serve as a new therapeutic target.

2.
Phytomedicine ; 58: 152866, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30831464

RESUMO

BACKGROUND: Herbal compatibility of compound formulas can enhance therapeutic effects or reduce side effects of the monarch drugs, but majority of compatibility mechanisms are still unknown. Sangju-Yin, a well-known Chinese compound formula, is currently used to treat common cold in clinical. PURPOSE: In this study, we proposed a strategy to explore the compatibility mechanism of Sangju-Yin by investigating P450 enzymes-based metabolic interactions between monarch drugs and the other constituent herbs. METHODS: Under the guidance of traditional Chinese medicine theory, the constituent herbs of Sangju-Yin were divided into four groups, including monarch drugs, monarch drugs with addition of minister drugs, monarch drugs with addition of minister and adjuvant drugs, as well as the whole recipe, namely monarch drugs with addition of minister, adjuvant and conductant drugs. Their effects on rats in vivo P450 (CYP1A2, CYP2A3, CYP2C6, CYP2C11 and CYP3A1) activities after oral administration were evaluated using probe drug assay based on LC-MS/MS. Moreover, effects of the four groups of herbs on mRNA expression of P450 enzymes after oral administration, as well as in vitro P450 activities after co-incubation, were investigated to explore the underlying mechanisms. RESULTS: Comparing with monarch drugs, addition of different constituent herbs significantly enhanced CYP1A2 and CYP2C6 activities, and inhibited CYP2A3 and CYP3A1 activities, indicating their possible influences on plasma concentrations of active constituents in the monarch drugs. Mechanism study suggested that these herbs affected P450 activities by transcriptional regulation and/or direct interaction with the enzymes. CONCLUSION: This study clarified the compatibility mechanism of Sangju-Yin from the aspect of P450 enzymes-based metabolic interactions, which would benefit better understanding of the therapeutic basis of Sangju-Yin.


Assuntos
Sistema Enzimático do Citocromo P-450/efeitos dos fármacos , Composição de Medicamentos , Interações de Medicamentos , Medicamentos de Ervas Chinesas/administração & dosagem , Medicina Tradicional Chinesa , Animais , Cromatografia Líquida , Sistema Enzimático do Citocromo P-450/metabolismo , Medicamentos de Ervas Chinesas/química , Masculino , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Espectrometria de Massas em Tandem
3.
J Antimicrob Chemother ; 74(6): 1511-1516, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-30820562

RESUMO

BACKGROUND: IS26-flanked transposons played an increasingly important part in the mobilization and development of resistance determinants. Heterogeneous resistance-encoding plasmid clusters with polymorphic MDR regions (MRRs) conferred by IS26 in an individual Escherichia coli isolate have not yet been detected. OBJECTIVES: To characterize the complete sequence of a novel blaCTX-M-65- and fosA3-carrying IncZ-7 plasmid with dynamic MRRs from an E. coli isolate, and to depict the mechanism underlying the spread of resistance determinants and genetic polymorphisms. METHODS: The molecular characterization of a strain carrying blaCTX-M-65 and fosA3 was analysed by antimicrobial susceptibility testing and MLST. The transferability of a plasmid bearing blaCTX-M-65 and fosA3 was determined by conjugation assays, and the complete structure of the plasmid was obtained by Illumina, PacBio and conventional PCR mapping, respectively. The circular forms derived from IS26-flanked transposons were detected by reverse PCR and sequencing. RESULTS: A novel IncZ-7 plasmid pEC013 (∼118kb) harbouring the blaCTX-M-65 and fosA3 genes was recovered from E. coli isolate EC013 belonging to D-ST117. The plasmid was found to have heterogeneous and dynamic MRRs in an individual strain and the IS26-flanked composite transposon-derived circular intermediates were identified and characterized in pEC013. CONCLUSIONS: The heterogeneous MRRs suggested that a single plasmid may actually be a cluster of plasmids with the same backbone but varied MRRs, reflecting the plasmid's heterogeneity and the survival benefits of having a response to antimicrobial-related threatening conditions in an individual strain.

4.
Mol Divers ; 22(3): 609-626, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29556864

RESUMO

Triethylamine-promoted cycloaddition reactions of N-phenacyl and N-alkoxycarbonylmethylbenzothiazolium bromides with aromatic aldehydes and malononitrile (ethyl cyanoacetate, pivaloylacetonitrile) in ethanol afforded functionalized tetrahydrobenzo[d]pyrrolo[2,1-b]thiazoles in good yields and various diastereoselectivity. The oxidation reaction of the functionalized tetrahydrobenzo[d]pyrrolo[2,1-b]thiazoles with DDQ in different solvents resulted in diverse benzothiazole derivatives and benzo[d]pyrrolo[2,1-b]thiazoles. The reaction mechanism and the stereochemistry of this tandem [3 [Formula: see text] 2] cycloaddition reaction and sequential oxidation reaction are illustrated based on analysis of the reactive intermediates and obtained products.


Assuntos
Benzotiazóis/síntese química , Acetatos/química , Benzotiazóis/química , Reação de Cicloadição , Etanol/química , Etilaminas/química , Nitrilos/química , Oxirredução , Solventes/química
5.
Drug Dev Ind Pharm ; 44(4): 563-569, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29148846

RESUMO

OBJECTIVE: Curcumin being used to treat various chronic diseases while its poor bioavailability issue limited its wide clinical application as a therapeutic agent. The aim of this work was to prepare curcumin-loaded self-assembled micelles using soluplus and solutol®HS15 (SSCMs) to enhance curcumin's solubility and thus oral bioavailability. METHODS: Optimum formulation was investigated and the optimized ratio of drugs and excipients was obtained and the SSCMs were prepared via ethanol solvent evaporation method. The optimal SSCMs were characterized by transmission electron microscopy, drug content analysis including loading efficiency (LE%) and entrapment efficiency (EE%), and the cumulative amount of curcumin released from the micelles were all calculated using HPLC method. The in vitro cytotoxicity and the permeability of SSCMs were measured by Caco-2 cell monolayers and the oral bioavailability was evaluated by SD rats. KEY FINDINGS: The solubility of curcumin in self-assembled micelles was dramatically increased by 4200 times as compared to free curcumin. Caco-2 cells transport experiment exhibited that while soluplus and solutol®HS15 were self-assembled into micelles, it could not only promote the permeability of curcumin across membrane for better absorption, but also could restrain the curcumin pumped outside due to the role of P-gp efflux mechanism of soluplus and solutol®HS15. Furthermore, the prepared SSCMs formulation was almost nontoxic and had safety performance on Caco-2 cells model. Moreover, curcumin's oral bioavailability of SSCMs formulation in SD rats had doubled than that of free curcumin. CONCLUSIONS: The prepared SSCMs were characterized by PS, PDI, LE%, EE% data analysis. After the soluplus and solutol®HS15 were self assembled into micelles, both the solubility and membrane permeability of curcumin were evaluated to have been enhanced, as well as the effect of efflux pump of curcumin was inhibited, hence to promote oral absorption and generate an increased bioavailability.


Assuntos
Curcumina/administração & dosagem , Animais , Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Disponibilidade Biológica , Células CACO-2 , Sobrevivência Celular , Curcumina/química , Curcumina/farmacocinética , Composição de Medicamentos , Excipientes , Humanos , Micelas , Polietilenoglicóis , Polivinil , Ratos , Ratos Sprague-Dawley , Solubilidade , Solventes
6.
Zhongguo Zhong Yao Za Zhi ; 42(19): 3764-3769, 2017 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-29235293

RESUMO

The present work is to study the chemical constituents from petroleum ether fraction of Tibetan medicine Swertia chirayita by column chromatography and recrystallization. The structures were identified by physical and chemical properties and spectral data as swerchirin (1), decussatin (2), 1,8-dihydroxy-3,5,7-trimethoxyxanthone (3), 1-hydroxy-3,5,7,8-tetramethoxyxanthone (4), bellidifolin (5), 1-hydroxy-3, 7-dimethoxyxanthone (6), methylswertianin (7), 1-hydroxy-3,5-dimethoxyxanthone (8), erythrodiol (9), oleanolic acid (10), gnetiolactone (11), scopoletin (12), sinapaldehyde (13), syringaldehyde (14), and ß-sitosterol (15). Compounds 3, 4, 9, 11-14 were isolated from S. chirayita for the first time. Compounds 9 and 12 were firstly isolated from the genus Swertia. The cytotoxic activities of compounds 1, 2, 5, 7 and 8 against human pancreatic cancer cell lines SW1990 and BxPC-3,and the protective effects of these compounds against hydrogen peroxide (H2O2)-induced oxidative stress in human endothelium-derived EA.hy926 were investigated in vitro. The results showed no obvious effect at the high concentration of 50 µmol•L⁻¹.

7.
J Pharm Biomed Anal ; 146: 68-78, 2017 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-28854404

RESUMO

Ginkgo biloba extract (GBE), derived from the leaves of Ginkgo biloba L., is one of the most widely used traditional Chinese medicines worldwide. Due to high structural diversity and low abundance of chemical constituents in GBE, conventional reversed-phase liquid chromatography has limited power to meet the needs of its quality control. In this study, an off-line hydrophilic interaction×reversed-phase two-dimensional liquid chromatography (HILIC×RP 2D-LC) system coupled with diode array detection (DAD) and quadrupole time-of-flight mass spectrometry (qTOF-MS) was established to comprehensively analyze the chemical constituents of GBE. After optimizing the chromatographic columns and mobile phase of 2D-LC, a Waters XBridge Amide column using acetonitrile/water/formic acid as the mobile phase was selected as the first dimension to fractionate GBE, and the obtained fractions were further separated on an Agilent Zorbax XDB-C18 column with methanol/water/formic acid as the mobile phase. As a result, a total of 125 compounds were detected in GBE. The orthogonality of the 2D-LC system was 69.5%, and the practical peak capacity was 3864 and 2994, respectively, calculated by two different methods. The structures of 104 compounds were tentatively characterized by qTOF-MS analysis, and 21 of them were further confirmed by comparing with reference standards. This established HILIC×RP 2D-LC-qTOF/MS system can greatly improve the separation and characterization of natural products in GBE or other complicated herbal extracts.


Assuntos
Medicamentos de Ervas Chinesas/química , Ginkgo biloba/química , Extratos Vegetais/química , Acetonitrilos/química , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia de Fase Reversa/métodos , Flavonoides/química , Formiatos/química , Interações Hidrofóbicas e Hidrofílicas , Medicina Tradicional Chinesa/métodos , Folhas de Planta/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Água/química
8.
Biochem Biophys Res Commun ; 485(3): 569-576, 2017 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-27913295

RESUMO

Alzheimer's disease (AD) is a neurodegenerative disorder that is the most common cause of dementia in the elderly, and intracellular neurofibrillary tangles (NFTs) are one of the pathological features of AD. Recent studies have suggested long noncoding RNAs (lncRNAs) play important roles in AD. Competing endogenous RNAs (ceRNAs) is a mechanism that has recently been proposed, in which lncRNAs compete for common miRNA-binding sites with mRNAs. However, the roles of lncRNAs and ceRNA in AD NFTs is limited. In this study, we constructed a global triple network based on ceRNA theory, then an AD NFT lncRNA-mRNA network (NFTLMN) was generated. By analyzing the NFTLMN, three lncRNAs (AP000265.1, KB-1460A1.5 and RP11-145M9.4), which are highly related with AD NFTs were identified. To further explore the cross-talk between mRNAs and lncRNAs, a clustering module analysis was performed on the NFTLMN and two AD NFT related modules were identified. Our study provides a better understanding of the molecular basis of AD NFTs and may offer novel treatment strategies for AD.

9.
J Chromatogr Sci ; 55(3): 334-345, 2017 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-27913377

RESUMO

Chromatographic separation is still a critical subject for the quality control of traditional Chinese medicine. In this study, three different high performance liquid chromatographic (HPLC) systems employing commercially available columns packed with 1.8, 3.5 and 5.0 µm particles were respectively developed and optimized for the combinative fingerprint analysis and multi-ingredients quantification of Sangju Ganmao tablet (SGT). Chromatographic parameters including the repeatability of retention time and peak area, symmetry factor, resolution, number of theoretical plates and peak capacity were used to assess the chromatographic performance of different HPLC systems. The optimal chromatographic system using Agilent ZORBAX SB-C18 column (2.1 mm × 100 mm, 3.5 µm) as stationary phase was respectively coupled with diode array detector or mass spectrometry detector for the chromatographic fingerprint analysis and simultaneous quantification or identification of nine compounds of SGT. All the validation data conformed to the acceptable requirements. For the fingerprint analysis, 31 peaks were selected as the common peaks to evaluate the similarities of SGT from 10 different manufacturers using heatmap, hierarchical cluster analysis and principal component analysis. The results demonstrated that the combinations of the quantitative and chromatographic fingerprint analysis offer an efficient way to evaluate the quality consistency of SGT.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/química , Espectrometria de Massas/métodos , Análise por Conglomerados , Limite de Detecção , Modelos Lineares , Análise de Componente Principal , Reprodutibilidade dos Testes , Comprimidos
10.
Curr HIV Res ; 15(1): 15-22, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27758709

RESUMO

BACKGROUND: Sterile alpha motif and histidine aspartate domain containing deoxynucleoside triphosphate triphosphohydrolase 1 (SAMHD1) is one of the novel restriction factors that potently supresses HIV-1 infection in myeloid cells at an early stage in the viral replication cycle. SAMHD1 activity is blocked by the action of viral accessory protein x (Vpx), which targets and recruits SAMHD1 for proteasomal degradation, in the SIVsm/HIV-2 lineage. METHODS: The impact of SAMHD1 polymorphisms on viral replication in Chinese-origin rhesus macaques (CR) and cynomolgus macaques of Vietnamese origin (CM) have not been reported until now. Therefore, we aimed to explore the polymorphisms, as well as the impact of polymorphisms, on HIV- 2 and SIV infections among CR and CM. RESULTS: We found two variants, T168C and T320C, located in the SAM domain of CR SAMHD1, which were significantly correlated with the HIV-2ROD/SIVmac239 virus load, suggesting that T168C and T320C probably affected HIV-2ROD and anti-SIVmac239 replication in CR, respectively. Conversely, T320C possibly affected CM SAMHD1-mediated HIV-2ROD restriction. However, none of the variants were correlated with CM SAMHD1-mediated SIVmac239 restriction. CONCLUSION: Based on these results, we concluded that SAMHD1 polymorphisms did not affect SIVmac239 replication in CM, but perhaps altered HIV-2ROD infection; however, different sites of the SAM domain of SAMHD1 were responsible for restricting the replication of different viruses in CR.


Assuntos
HIV-2/isolamento & purificação , Leucócitos Mononucleares/virologia , Polimorfismo Genético , Proteína 1 com Domínio SAM e Domínio HD/genética , Vírus da Imunodeficiência Símia/isolamento & purificação , Carga Viral , Animais , Interações Hospedeiro-Patógeno , Macaca fascicularis , Macaca mulatta
11.
Proc Biol Sci ; 283(1840)2016 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-27733547

RESUMO

Viral selection pressure has acted on restriction factors that play an important role in the innate immune system by inhibiting the replication of viruses during primate evolution. Tripartite motif-containing (TRIM) family members are some of these restriction factors. It is becoming increasingly clear that gene expression differences, rather than protein-coding regions changes, could play a vital role in the anti-retroviral immune mechanism. Increasingly, recent studies have created genome-scale catalogues of DNase I hypersensitive sites (DHSs), which demark potentially functional regulatory DNA. To improve our understanding of the molecular evolution mechanism of antiviral differences between species, we leveraged 14 130 DHSs derived from 145 cell types to characterize the regulatory landscape of the TRIM region. Subsequently, we compared the alignments of the DHSs across six primates and found 375 DHSs that are conserved in non-human primates but exhibit significantly accelerated rates of evolution in the human lineage (haDHSs). Furthermore, we discovered 31 human-specific potential transcription factor motifs within haDHSs, including the KROX and SP1, that both interact with HIV-1 Importantly, the corresponding haDHS was correlated with antiviral factor TRIM23 Thus, our results suggested that some viruses may contribute, through regulatory DNA differences, to organismal evolution by mediating TRIM gene expression to escape immune surveillance.


Assuntos
Evolução Molecular , Primatas/genética , Sequências Reguladoras de Ácido Nucleico , Seleção Genética , Proteínas com Motivo Tripartido/genética , Animais , Proteínas de Ligação ao GTP/genética , Genoma , HIV-1 , Humanos
12.
Int J Clin Exp Med ; 8(9): 16564-70, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26629185

RESUMO

Nasopharyngeal Carcinoma (NPC) patients' end-of-treatment survival status has drawn more attention in recent years. Telephone follow-up, as a most operative approach among all the clinical follow-ups, is an effective means to extend medical service to patients' home and is thus widely used in clinical practice. This study aimed to analyze the post-radiotherapy NPC patients' phone response rate and its factors, and to discuss the independent prognostic factors of NPC patients' radiotherapy. We prospectively designed a nurses-led telephone follow-up to include 2520 NPC patients who received simple radical radiotherapy between Jan. 2007 and Jun. 2012 at Sun Yat-sen University Cancer Center. The patients' response rate and its factors were calculated. Survival analysis was used to estimate the patients' survival and the influencing factors. The overall response rate was 90.5%; Patients with reserved contact type of mobile + landlinephone or landline phone had higher follow-up response rate than patients with mobile contact only; patients with 2 or more reserved contacts, and family cancer history had higher response rate than patients with only 1 number and those without family history. Patients' cumulative survival rate of 1, 3 and 5 years were 98.9%, 75.3%, 50.3%, respectively. T-staging, N-staging, higher clinical staging, with basicranial invasion were the influencing factors of the patients' poor prognosis. The telephone follow-up response was affected by reserved contact type, number of contacts and family medical history; T-staging, N-staging, higher clinical staging, with basicranial invasion were the influencing factors of the patients' poor prognosis. This study provides a scientific basis for increasing the NPC patients' end-of-treatment response and promoting the individualized clinical treatment.

13.
Phytomedicine ; 22(12): 1088-95, 2015 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-26547531

RESUMO

BACKGROUND: The aerial parts of Peganum harmala L. (APP) is a well-known and effective herbal medicine in China, and has been commonly used for treating various ailments, including cough and asthma. OBJECTIVES: To evaluate the antitussive, expectorant, and bronchodilating effects of the quinazoline alkaloids (±)-vasicine (VAS), deoxyvasicine (DVAS) (both isolated from the alkaloid fraction of APP) and (±)-vasicinone (VAO) (synthesized from VAS). METHODS: The three quinazoline alkaloids were tested as antitussive on cough models in mice and guinea pigs. VAO was synthesized from VAS via the oxidation of hydrogen peroxide. VAS, VAO, and DVAS were orally administered at dosages of 5, 15, and 45 mg/kg. Cough in these models was induced by ammonia, capsaicin, and citric acid. Phenol red secretion experiments in mice were performed to evaluate the expectorant activity of the alkaloids. Bronchodilating effects were evaluated by using a bronchoconstrictive induced by acetylcholine chloride and histamine in guinea pigs. RESULTS: In antitussive tests, VAS, VAO, and DVAS significantly inhibited coughing frequency and prolonged the cough latency period in animals. At the highest doses tested (45 mg/kg), they showed antitussive activities similar to codeine phosphate (30 mg/kg) in mice and guinea pigs. Expectorant evaluation showed that VAS, VAO, and DVAS could significantly increase phenol red secretion in mice by 0.54-, 0.79- and 0.97-fold, by 0.60-, 0.99-, and 1.06-fold, and by 0.46-, 0.73-, and 0.96-fold, respectively, at dosages of 5, 15, and 45 mg/kg compared with the control (0.5% CMC-Na, 20 ml/kg). Ammonium chloride at 1500 mg/kg increased phenol red secretion in mice by 0.97-fold compared with the control. Bronchodilation tests showed that VAS, VAO, and DVAS prolonged the pre-convulsive time for 28.59%, 57.21%, and 29.66%, respectively, at a dose of 45 mg/kg in guinea pigs, whereas aminophylline prolonged the pre-convulsive time by 46.98% compared with pretreatment. CONCLUSIONS: Quinazoline alkaloids VAS, VAO, and DVAS have significant antitussive, expectorant, and bronchodilating activities. VAS, VAO, and DVAS are the active ingredients in APP, which can be used to treat respiratory disease.


Assuntos
Alcaloides/farmacologia , Antitussígenos/farmacologia , Broncodilatadores/farmacologia , Expectorantes/farmacologia , Peganum/química , Quinazolinas/farmacologia , Alcaloides/isolamento & purificação , Animais , Antitussígenos/isolamento & purificação , Broncoconstrição/efeitos dos fármacos , Broncodilatadores/isolamento & purificação , Tosse/tratamento farmacológico , Medicamentos de Ervas Chinesas/química , Expectorantes/isolamento & purificação , Feminino , Cobaias , Masculino , Camundongos , Estrutura Molecular , Componentes Aéreos da Planta/química , Plantas Medicinais/química , Quinazolinas/isolamento & purificação
14.
Biomed Chromatogr ; 29(12): 1791-7, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26033261

RESUMO

Folium Eriobotryae effective fraction (FEA), the extract of Folium Eriobotryae, had been used as anti-hyperglycemia and anti-hyperlipemia medicine in China. A previous study indicated that euscaphic acid, maslinic acid, corosolic acid, oleanolic acid and ursolic acid, the five structurally similar triterpene acids (containing two groups of structural isomers), are the major components of FEA. In the present study, we developed a specific and reliable LC-MS method for simultaneous determination of the five triterpene acids in rat plasma, and further investigated their pharmacokinetic properties after oral administration of FEA. Following a simple sample preparation, chromatographic separation was achieved on a C18 column with a mobile phase composed of methanol-0.1% ammonium acetate (80:20, v/v). Quantification was achieved by monitoring the selected ions at m/z 487.6 for euscaphic acid, m/z 471.5 for maslinic acid and corosolic acid, m/z 455.5 for oleanolic acid and ursolic acid and m/z 469.5 for internal standard. The method was validated to be specific, accurate and precise over the concentration ranges of 10-3000 ng/mL with limits of detections of 5 ng/mL for the five triterpene acids. Finally, the method was successfully applied to the pharmacokinetic study of the five structurally similar triterpene acids in rats after oral administration of FEA.


Assuntos
Cromatografia Líquida/métodos , Espectrometria de Massas/métodos , Triterpenos/sangue , Triterpenos/farmacocinética , Administração Oral , Animais , Estabilidade de Medicamentos , Medicamentos de Ervas Chinesas/administração & dosagem , Limite de Detecção , Modelos Lineares , Masculino , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Triterpenos/química , Triterpenos/isolamento & purificação
15.
Anal Chem ; 87(3): 1499-502, 2015 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-25569205

RESUMO

The lysosome-targetable OFF-ON type pH sensor that does not emit at pH = 4.0 is adopted for the selective detection of cancer cells, and the acidity difference of lysosomes in cancer and normal cells is verified. Three pH probes based on Darrow Red derivatives were designed and prepared that were demonstrated to be lysosome-specific biomarkers with inducible emission at 580-850 nm by the comparable in cellular imaging assays using HeLa, KB, and V79 cells. Of these, a pyridineium-2-yl Darrow Red analogue with a pKa of 2.4 was found to be a lysosome tracker for cancer cells, it is a unique pH sensor for the optical identification and distinction of cancer cells from normal cells and has potential application as a fluorescent biomaker of cancer cells in in vitro assays.


Assuntos
Benzoxazinas , Corantes Fluorescentes , Lisossomos/patologia , Neoplasias/diagnóstico , Imagem Óptica , Benzoxazinas/química , Linhagem Celular Tumoral , Corantes Fluorescentes/química , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Microscopia Confocal
16.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(8): 2229-33, 2014 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-25474967

RESUMO

It's significant to study the algorithm of endmember extraction, which is the key for pixel unmixing,in the fields of feature identification, abundance inversion, quantitative remote sensing and so on. Based on the theory of shannon entropy and Gaussian distribution function, a new algorithm, named spectral minimum shannon entropy (SMSE) method for extracting end-members of hyperspectral images, is proposed in the present paper after analyzing the characteristics of spectra of the hyperspectral images. This algorithm was applied to extract the endmembers of an AVRIRS hyperspectral image, it was found that these extracted endmember spectra have higher precision by matching with the spectral library of United States Geological Survey (USGS). At the same time, it was also found that the SMSE algorithm has better efficiency and accuracy for extracting endmember spectra through comparing and analyzing comprehensively the results of endmember extraction of the experimental data by using the methods of SMSE, pixel purity index (PPI), sequential maximum angle convex cone (SMACC) and so on. In addition, the SMACC and SMSE are used to extract the endmembers in a Hyperion hyperspectral image, and it is concluded that the results of the SMSE is better than the SMACC's. Thus, the SMSE algorithm can be thought to have a certain degree of universal applicability.

17.
Open Biomed Eng J ; 8: 142-6, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25852784

RESUMO

OBJECTIVE: In this paper, we have done Bayes Discriminant analysis to EEG data of experiment objects which are recorded impersonally come up with a relatively accurate method used in feature extraction and classification decisions. METHODS: In accordance with the strength of α wave, the head electrodes are divided into four species. In use of part of 21 electrodes EEG data of 63 people, we have done Bayes Discriminant analysis to EEG data of six objects. Results In use of part of EEG data of 63 people, we have done Bayes Discriminant analysis, the electrode classification accuracy rates is 64.4%. CONCLUSIONS: Bayes Discriminant has higher prediction accuracy, EEG features (mainly αwave) extract more accurate. Bayes Discriminant would be better applied to the feature extraction and classification decisions of EEG data.

18.
Nan Fang Yi Ke Da Xue Xue Bao ; 29(8): 1629-31, 2009 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-19726313

RESUMO

OBJECTIVE: To investigate the effects of co-exposure of LPS and heat on TNF-alpha expression in rat kidneys. METHODS: Male pathogen-free Wistar rats were randomly assigned in saline-injected normothermic control (C group), saline-injected heat exposure (H group), LPS-injected normothermic control (L group), and LPS-injected heat exposure (HL group). The rats in H and HL groups were exposed in a chamber at an ambient dry bulb temperature (Tdb) of 35.0-/+0.5 degrees, and those in C and L groups were exposed to a Tdb of 26-/+0.5 degrees. The rats in L and HL groups were given an intravenous injection of LPS (10 mg/kg) via the tail vein to induce endotoxemia, and equivalent normal saline was injected in C and H groups. TNF-alpha expression in the kidney was detected by immunohistochemical SABC method, and the renal damage was evaluated histologically at 120 min after the treatment. RESULTS: Co-exposure of the rats with LPS and heat caused significantly enhanced TNF-alpha expression and histopathological damage in the kidneys. CONCLUSION: LPS combined with heat exposure causes renal toxicity, while is closely associated with the expression of TNF-alpha in the kidneys.


Assuntos
Regulação da Expressão Gênica , Temperatura Alta , Rim/efeitos dos fármacos , Rim/metabolismo , Lipopolissacarídeos/farmacologia , Estresse Fisiológico/efeitos dos fármacos , Fator de Necrose Tumoral alfa/metabolismo , Animais , Imuno-Histoquímica , Interleucinas/metabolismo , Rim/patologia , Masculino , Ratos , Ratos Wistar
19.
Shock ; 32(5): 524-9, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19295493

RESUMO

The present study was attempted to assess the prophylactic and the therapeutic effect of human recombinant activated protein C (APC; drotrecogin-alpha, activated) in experimental heat stroke. Anesthetized rats were divided into two groups and given vehicle solution 1 h before the start or immediately after the termination of heat stress (isotonic sodium chloride solution, 2 mL kg(-1) of body weight, i.v.) or APC (1-10 mg in 2 mL of isotonic sodium chloride solution per kilogram of body weight, i.v.). They were exposed to ambient temperature of 40 degrees C for 100 min to induce heat stroke. When the vehicle-pretreated rats underwent heat stress, their survival time values were found to be 57 to 71 min. Pretreatment or treatment with APC significantly increased survival time (122-221 min). All vehicle-pretreated heat stroke animals displayed systemic inflammation (evidenced by increased TNF-alpha, IL-1alpha, and IL-6) and activated coagulation (evidenced by increased levels of activated partial thromboplastin time, prothrombin time, and D-dimer and decreased levels of both platelet count and protein C). Biochemical assay also revealed that both renal and hepatic dysfunction (e.g., increased plasma levels of blood urea nitrogen, creatinine, adenine aminotransferase, aspartate aminotransferase, and alkaline phosphatase) were noted during heat stroke. A significant decrease in both cerebral blood flow and partial pressure of oxygen in hypothalamus were also observed in vehicle-pretreated heat stroke animals. These heat stroke reactions were all significantly reduced by pretreatment or treatment with human recombinant APC. The results indicate that human recombinant APC can be used as a prophylactic and a therapeutic agent for experimental heat stroke by ameliorating systemic inflammation, hypercoagulable state, and multiple organ dysfunction.


Assuntos
Anti-Infecciosos/farmacologia , Golpe de Calor , Inflamação/prevenção & controle , Proteína C/farmacologia , Fosfatase Alcalina/metabolismo , Aminoidrolases/metabolismo , Animais , Aspartato Aminotransferases/metabolismo , Coagulação Sanguínea/efeitos dos fármacos , Febre/prevenção & controle , Golpe de Calor/tratamento farmacológico , Golpe de Calor/imunologia , Humanos , Hipotensão/prevenção & controle , Interleucina-1alfa/metabolismo , Interleucina-6/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley , Proteínas Recombinantes/farmacologia , Fator de Necrose Tumoral alfa/metabolismo
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