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1.
Colloids Surf B Biointerfaces ; 183: 110414, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31404790

RESUMO

Pickering emulsions have received widespread attention for encapsulating lipophilic guests in the biomedical and food fields. However, control of the stabilities and demulsification of Pickering emulsions to allow the release of encapsulated species remains a challenge in gastrointestinal conditions. In this work, phosphatidylcholine-kaolinite was prepared by modification of natural kaolinite with phosphatidylcholine and was used as an emulsifier to stabilize medium-chain triglyceride (MCT)/water Pickering emulsions for encapsulating curcumin, a natural antioxidant drug. Simulated gastric and intestinal digestion and a cell uptake assay were implemented for the curcumin-loaded MCT/water Pickering emulsion to study its demulsification and the bioavailability of curcumin. The results revealed that the wettability of phosphatidylcholine-kaolinite could be tailored by controlling the modification temperature so that it could control the emulsion stability. The prepared phosphatidylcholine-kaolinite, with a three-phase contact angle of 123°, was an optimal emulsifier for the enhanced stabilization of the MCT/water Pickering emulsion, especially in the presence of gastric acid. The phosphatidylcholine-kaolinite distributed at the water-oil interface and formed a dense shell structure on the surfaces of the emulsion droplets, controlling the demulsification efficiency to release the encapsulated curcumin. Only 18.9% of the curcumin was released in the simulated gastric conditions after 120 min of digestion due to the demulsification of the MCT/water Pickering emulsion, while it was completely released after 150 min of digestion in simulated intestinal conditions, as expected. This Pickering emulsion stabilized by phosphatidylcholine-kaolinite is a promising delivery system for lipophilic foods or drugs to enhance their bioavailability.

2.
Mitochondrial DNA A DNA Mapp Seq Anal ; 30(2): 222-225, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-29790807

RESUMO

Mammalian mitochondrial A1555G and C1494T mutations are the most common causes of aminoglycoside-induced and non-syndromic hearing loss. However, these two mutations always are studied in the subject of pedigrees analysis. In the present study, we aimed to investigate the genetic characteristic of the A1555G and C1494T mutations on the population-level sampling, and to study the A1555G pattern of maternal transmission in three heteroplasmic families. Four thousand two hundred and ten unrelated women with normal hearing were enrolled as subjects. We used a mutation detection kit to screen the prevalence of these two mutations and used denaturing high performance liquid chromatography (DHPLC) and DNA sequencing to detect three A1555G heteroplasmic pedigrees. The carrier rate of A1555G was 0.33%, and the carrier rate of C1494T was 0.02% in our cohort, but the rate of heteroplasmy in A1555G mutant carriers reached 21.4%. Mitochondrial A1555G mutation rate was significantly decreased during maternal transmission of the mutant. Strong purifying selection may determine the fate of mtDNA A1555G in the transmission of human population.


Assuntos
DNA Mitocondrial/genética , Perda Auditiva Neurossensorial/genética , Herança Materna , Mutação de Sentido Incorreto , RNA Ribossômico/genética , Adulto , Aminoglicosídeos/toxicidade , Feminino , Perda Auditiva Neurossensorial/induzido quimicamente , Humanos , Taxa de Mutação , Polimorfismo Genético
4.
Wei Sheng Wu Xue Bao ; 52(5): 645-53, 2012 May 04.
Artigo em Chinês | MEDLINE | ID: mdl-22803351

RESUMO

OBJECTIVE: In order to study the characteristic of nitrogen transport, the community structure and diversity of related microorganisms in aquaculture water of the Pearl River Delta. METHODS: We established an artificial aquaculture ecosystem to study the microbial community of 15N-stable isotope probing (15N-SIP) labeled nitrogen transport microorganisms. The 15N-labeled DNA was separated by CsCl-ethidium bromide density gradient centrifugation, and was used to construct 16S rRNA gene clone libraries of bacteria and archaea. RESULTS: Phylogenetic analysis shows that 19 Operational Taxonomic Units (OTUs) from bacterial library were clustered in Proteobacteria and Planctomycetes. Proteobacteria (99.2%) was the dominant group, mainly consisted of Comamonas (15.7%), Nitrosomonas (12.4%), Enterobacteriaceae (11.5%) and Nitrobacter (11.5%). From archaeal library 9 OTUs were divided into 3 phyla: Thaumarchaeota, Crenarchaeota and Euryarchaeota. CONCLUSION: We successfully elucidated the microbial community of nitrogen transport microorganisms in aquaculture water of Pearl River Delta by using 15N-SIP. The data of the community will provide essential information for isolating nitrogen degrading microorganism, and provide scientific basis for creating a healthy aquaculture environment.


Assuntos
Archaea/isolamento & purificação , Bactérias/isolamento & purificação , Nitrogênio/metabolismo , Rios/microbiologia , Aquicultura , Archaea/genética , Archaea/metabolismo , Bactérias/genética , Bactérias/metabolismo , China , Ecossistema , Ciclo do Nitrogênio , Filogenia
5.
Exp Physiol ; 97(10): 1105-18, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22562809

RESUMO

Intermittent hypobaric hypoxia (IHH) is an effective protective strategy against myocardial ischaemia-reperfusion (I/R) injury, but the precise mechanisms are far from clear. To understand the overall effects of IHH on the myocardial proteins during I/R, we analysed functional performance and the protein expression profile in isolated hearts from normoxic rats and from rats adapted to IHH (5000 m, 4 h day(-1), 4 weeks) following I/R injury (30 min/45 min). Intermittent hypobaric hypoxia significantly improved the postischaemic recovery of left ventricular function compared with the recovery in time-matched normoxic control hearts. Two-dimensional electrophoresis with matrix-assisted laser desorption/ionization and time-of-flight mass spectrometric analysis was then used to assess protein alterations in left ventricles from normoxic and IHH groups, with or without I/R. The expressions of 16 proteins changed by over fivefold; nine of these proteins are involved in energy metabolism. Immunoblot and real-time PCR analysis confirmed the IHH-increased expressions of the ATP synthase subunit ß, mitochondrial aldehyde dehydrogenase and heat shock protein 27 in left ventricles. Furthermore, IHH significantly attenuated the reduction of myocardial ATP content, mitochondrial ATP synthase activity, membrane potential and respiratory control ratios due to I/R. In addition, inhibition of mitochondrial ATP synthase by oligomycin (1 µmol l(-1)) abolished the IHH-induced improvements in three parameters: postischaemic recovery of left ventricular function, mitochondrial membrane potential and respiratory control ratios. These results suggest that an improvement in mitochondrial energy metabolism makes an important contribution to the cardioprotection afforded by IHH against postischaemic myocardial dysfunction.


Assuntos
Hipóxia/metabolismo , Mitocôndrias Cardíacas/metabolismo , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Trifosfato de Adenosina/metabolismo , Aldeído Desidrogenase/metabolismo , Animais , Metabolismo Energético , Proteínas de Choque Térmico HSP27/metabolismo , Ventrículos do Coração/metabolismo , Masculino , Potencial da Membrana Mitocondrial , ATPases Mitocondriais Próton-Translocadoras/metabolismo , Infarto do Miocárdio/metabolismo , Miocárdio/metabolismo , Proteoma/metabolismo , Ratos , Ratos Sprague-Dawley , Função Ventricular Esquerda/fisiologia
6.
Guang Pu Xue Yu Guang Pu Fen Xi ; 32(11): 2962-5, 2012 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-23387158

RESUMO

To simplify the model and improve the precision of prediction model, latent projective graph (LPG) was used for variable selection. The original spectrum was processed by continuous wavelet transform (CWT), LPG was obtained by principal component analysis (PCA), and based on the assumption that collinear wavelengths might have the same contribution to the modeling, a few latent spectral variables were selected for establishing prediction model. The root mean square error of prediction (RMSEP) model was 0. 3454, better than other modeling methods. This work proved that variable selection with LPG could simplify the near-infrared spectral model effectively, and improve the precision of prediction model.


Assuntos
Modelos Teóricos , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Triticum/química , Previsões , Proteínas de Plantas/química , Análise de Componente Principal/métodos , Máquina de Vetores de Suporte , Análise de Ondaletas
7.
Am J Physiol Heart Circ Physiol ; 301(4): H1695-705, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21821784

RESUMO

Intermittent hypobaric hypoxia (IHH) protects hearts against ischemia-reperfusion (I/R) injury, but the underlying mechanisms are far from clear. ROS are paradoxically regarded as a major cause of myocardial I/R injury and a trigger of cardioprotection. In the present study, we investigated whether the ROS generated during early reperfusion contribute to IHH-induced cardioprotection. Using isolated perfused rat hearts, we found that IHH significantly improved the postischemic recovery of left ventricular (LV) contractile function with a concurrent reduction of lactate dehydrogenase release and myocardial infarct size (20.5 ± 5.3% in IHH vs. 42.1 ± 3.8% in the normoxic control, P < 0.01) after I/R. Meanwhile, IHH enhanced the production of protein carbonyls and malondialdehyde, respective products of protein oxidation and lipid peroxidation, in the reperfused myocardium and ROS generation in reperfused cardiomyocytes. Such effects were blocked by the mitochondrial ATP-sensitive K(+) channel inhibitor 5-hydroxydecanoate. Moreover, the IHH-improved postischemic LV performance, enhanced phosphorylation of PKB (Akt), PKC-ε, and glycogen synthase kinase-3ß, as well as translocation of PKC-ε were not affected by applying H(2)O(2) (20 µmol/l) during early reperfusion but were abolished by the ROS scavengers N-(2-mercaptopropionyl)glycine (MPG) and manganese (III) tetrakis (1-methyl-4-pyridyl)porphyrin. Furthermore, IHH-reduced lactate dehydrogenase release and infarct size were reversed by MPG. Consistently, inhibition of Akt with wortmannin and PKC-ε with εV1-2 abrogated the IHH-improved postischemic LV performance. These findings suggest that IHH-induced cardioprotection depends on elevated ROS production during early reperfusion.


Assuntos
Hipóxia/fisiopatologia , Contração Miocárdica/fisiologia , Isquemia Miocárdica/fisiopatologia , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Reperfusão Miocárdica , Transdução de Sinais/fisiologia , Pressão do Ar , Animais , Antioxidantes/farmacologia , Sobrevivência Celular/fisiologia , Cistina/análogos & derivados , Cistina/farmacologia , Ativação Enzimática/fisiologia , Canais KATP/metabolismo , L-Lactato Desidrogenase/metabolismo , Peroxidação de Lipídeos , Masculino , Mitocôndrias Cardíacas/metabolismo , Mitocôndrias Cardíacas/fisiologia , Infarto do Miocárdio/patologia , Miócitos Cardíacos/fisiologia , Proteína Oncogênica v-akt/metabolismo , Proteína Oncogênica v-akt/fisiologia , Oxirredução , Proteína Quinase C-épsilon/metabolismo , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Recuperação de Função Fisiológica
8.
Cardiovasc Res ; 79(3): 500-8, 2008 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-18397962

RESUMO

AIMS: Heat shock protein 27 (Hsp27) renders cardioprotection from ischaemia/reperfusion (I/R) injury, but little is known about its role in myofilaments. We proposed that increased expression of Hsp27 may improve post-ischaemic contractile dysfunction by preventing I/R-induced cardiac troponin I (cTnI) and troponin T (cTnT) degradation. METHODS AND RESULTS: Adenovirus-mediated Hsp27 overexpression improved contractile function in perfused rat hearts subjected to global no-flow I/R (30-min/30-min). Such improvement was further confirmed in Hsp27-overexpressing cardiomyocytes subjected to simulated I/R (20-min/30-min). Moreover, these cells showed restored myofilament response to Ca(2+) but not intracellular Ca(2+) transients. The protection correlated with attenuation of I/R-induced cTnI and cTnT degradation. Confocal microscopy revealed co-localization of Hsp27 with these proteins. Co-immunoprecipitation and pull-down assays further confirmed that Hsp27 interacted with the COOH-terminus of cTnI and the NH(2)-terminus of cTnT and that Hsp27 overexpression decreased the interaction between mu-calpain (a protease mediating proteolysis of cTnI and cTnT) and cTnI or cTnT under I/R. CONCLUSION: The findings reveal a novel role of Hsp27 in the protection of cTnI and cTnT from I/R-induced degradation by preventing their proteolytic cleavage via interacting with these proteins. Such protection may result in restored post-ischaemic myofilament response to Ca(2+) and improved post-ischaemic contractile function.


Assuntos
Proteínas de Choque Térmico HSP27/biossíntese , Contração Miocárdica , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Miocárdio/metabolismo , Troponina I/metabolismo , Troponina T/metabolismo , Função Ventricular Esquerda , Citoesqueleto de Actina/metabolismo , Adenoviridae/genética , Animais , Sinalização do Cálcio , Calpaína/metabolismo , Células Cultivadas , Modelos Animais de Doenças , Vetores Genéticos , Proteínas de Choque Térmico HSP27/genética , Humanos , Masculino , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Perfusão , Ratos , Ratos Sprague-Dawley , Fatores de Tempo , Transdução Genética
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