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1.
Dev Comp Immunol ; 119: 104013, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33465381

RESUMO

Programmed cell death 4 (PDCD4) in mammals, a gene closely associated with apoptosis, is involved in many biological processes, such as cell aging, differentiation, regulation of cell cycle, and inflammatory response. In this study, grouper Epinephelus coioides PDCD4, EcPDCD4-1 and EcPDCD4-2, were obtained. The open reading frame (ORF) of EcPDCD4-1 is 1413 bp encoding 470 amino acids with a molecular mass of 52.39 kDa and a theoretical pI of 5.33. The ORF of EcPDCD4-2 is 1410 bp encoding 469 amino acids with a molecular mass of 52.29 kDa and a theoretical pI of 5.29. Both EcPDCD4-1 and EcPDCD4-2 proteins contain two conserved MA3 domains, and their mRNA were detected in all eight tissues of E. coioides by quantitative real-time PCR (qRT-PCR) with the highest expression in liver. The expressions of two EcPDCD4s were significantly up-regulated after Singapore grouper iridovirus (SGIV) or Vibrio alginolyticus infection. In addition, over-expression of EcPDCD4-1 or EcPDCD4-2 can inhibit the activity of the nuclear factor-κB (NF-κB) and activator protein-1 (AP-1), and regulate SGIV-induced apoptosis. The results demonstrated that EcPDCD4s might play important roles in E. coioides tissues during pathogen-caused inflammation.

2.
Dev Comp Immunol ; 119: 104020, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33476669

RESUMO

Mitogen-activated protein kinase 4 (MKK4), a member of the MAP kinase family, play important roles in response to many environmental and cellular stresses in mammals. In this study, three MKK4 subtypes, EcMKK4-1, EcMKK4-2 and EcMKK4-3, were obtained from grouper Epinephelus coioides. The open reading frame (ORF) of EcMKK4s are obtained and the EcMKK4s proteins contain highly conserved domains: a S_TKc domain, a canonical diphosphorylation group and two conserved MKKK ATP binding motifs, Asp-Phe-Gly (DFG) and Ala-Pro-Glu (APE). EcMKK4s could be found both in the cytoplasmic and nuclear. The EcMKK4s mRNA were detected in all E. coioides tissues examined with the different expression levels, and the expression were up-regulated during SGIV (Singapore grouper iridescent virus) or Vibrio alginolyticus infection. EcMKK4 could significantly reduce the activation of AP-1 reporter gene. The results suggested that EcMKK4s might play important roles in pathogen-caused inflammation.

4.
Huan Jing Ke Xue ; 41(5): 2247-2256, 2020 May 08.
Artigo em Chinês | MEDLINE | ID: mdl-32608842

RESUMO

The safety of water quantity and quality caused by large-scale blackwater in reservoirs with Eucalyptus plantation is currently a point of great interest. Eucalyptus is largely planted in southern China, especially in Nanning, Guangxi, where more than 90% of the drinking water source reservoirs are surrounded by Eucalyptus, and different degrees of blackwater often occur in many reservoirs. Recent research has demonstrated that reservoir sediments play an important role in the migration and transformation of Fe2+, Mn2+, S2-, and dissolved organic carbon (DOC) in the overlying water. It is of great significance to explore the distribution characteristics and migration rules of pollutants in the sediment-water interface to reveal the mechanism of blackwater in reservoirs. Experiments were carried out three times in a typical blackwater reservoir (Tianbao Reservoir) in southern China from July to December 2018. The distribution characteristics and seasonal variations of iron, manganese, sulfide, and organic matter in sediments were analyzed, focusing mainly on the profile distribution and migration direction of Fe2+, Mn2+, S2- and DOC in pore water during blackwater periods. The results showed that:① The content of iron and manganese in sediments of reservoirs with Eucalyptus plantation is high, far exceeding the background value of soil content in China. The content of iron, manganese, and total organic carbon (TOC) in the surface sediments increases simultaneously, mainly caused by the input and settlement of the material (litter, decomposed liquids. and soil particles) in the Eucalyptus forest around the reservoir. ② The concentration of Fe2+(16.99 mg·L-1) and the content of DOC (36.80%) in pore water during the blackwater period are significantly higher than those in Taihu Lake during the black bloom (12.15 mg·L-1, 10.78%). The mean concentrations of Fe2+ and Mn2+ are more than 300 times higher than that of S2-, and the reduction conditions in the sediments are dominated by iron and manganese oxides. ③ The diffusion flux of Fe2+ is 27.4-33.5 mg·(m2·d)-1, which is 32.6, 4.9, and 30.8 times higher than those of Taihu Lake, Aha Reservoir, and Hongfeng Lake, respectively. This implies strong Fe2+ release ability from sediments to the overlying water. As a positive correction exists between Fe2+ and DOC, the complex reaction between Fe2+ and organic matter is one of the most important causes of blackwater in reservoirs with Eucalyptus plantation.

5.
Fish Shellfish Immunol ; 97: 125-134, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31809835

RESUMO

Heat shock protein 22 (Hsp22) is an important regulatory factor response to various stresses in mammals. In this study, the full length cDNA of Epinephelus coioides Hsp22, which was 1680bp in length, with a 289 bp 5' UTR, a 725 bp 3'UTR, and a 666 bp open reading frame encoding 221 amino acids, was obtained. E. coioides Hsp22 contains a highly conserved α-crystallin domain. E. coioides Hsp22 mRNA was detected in all tissues examined by quantitative real-time PCR, with the highest expression in blood, followed by the spleen, skin, gill, head kidney, muscle, heart, liver, trunk kidney, stomach, pyloric caeca, intestine, brain and thymus. The expression patterns of E. coioides Hsp22 response to infection with Singapore grouper iridovirus (SGIV) and Vribro alginolyticus, the important pathogens of E. coioides, were studied. The expression levels of the gene were up-regulated in the tissues examined. Subcellular localization analysis demonstrated that E. coioides Hsp22 was distributed in both the cytoplasm and nucleus. In addition, E. coioides Hsp22 significantly inhibited the SGIV-induced cell apoptosis. In summary, the E. coioides Hsp22 might play a critical role in pathogenic stimulation.


Assuntos
Bass/imunologia , Proteínas de Peixes/genética , Proteínas de Choque Térmico/genética , Vibrioses/veterinária , Viroses/veterinária , Animais , Bass/microbiologia , Bass/virologia , Clonagem Molecular , Doenças dos Peixes/imunologia , Doenças dos Peixes/microbiologia , Doenças dos Peixes/virologia , Expressão Gênica , Proteínas de Choque Térmico/imunologia , Iridovirus , Vibrioses/imunologia , Vibrio alginolyticus , Viroses/imunologia
6.
Med Sci Monit ; 25: 2687-2694, 2019 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-30977468

RESUMO

BACKGROUND Research interest in endothelial nitric oxide synthase(eNOS) polymorphisms and atrial fibrillation (AF) has grown in last recent years, but the results of individual studies are inconsistent due to their small sample sizes. MATERIAL AND METHODS We searched databases for eligible studies on eNOS and AF, extracted the relevant data, and rigorously screened them according to inclusion and exclusion criteria. Then, we evaluated the study quality according to the Newcastle-Ottawa scale score, and we pooled the odds ratios (ORs) and 95% confidence intervals (CIs) by using a random-effects model or fixed-effects model based on inter-study heterogeneity. In addition, we performed subgroup analysis and sensitivity analysis and assessed publication bias. RESULTS According to the inclusion and exclusion criteria, we finally found 8 studies in this search. The recessive (OR=0.81; 95% CI=0.67 to 0.97; p=0.988; I²=0.0%) model showed that the eNOS 786T/C polymorphism was relevant to AF. We also found that the eNOS 786T/C polymorphism decreases the risk of AF, especially in white people (OR=0.81; 95% CI=0.67 to 0.97; P=0.023 for recessive model) and in the control population (OR=0.79; 95% CI=0.65 to 0.97; P=0.022 for recessive model). We found no obvious publication bias. CONCLUSIONS The eNOS gene loci 786T/C polymorphism is relevant to the risk of AF. Our results suggest that the 786T/C polymorphism significantly decreases AF risks in white people and control populations. Larger studies are required for further evaluation.


Assuntos
Fibrilação Atrial/enzimologia , Fibrilação Atrial/genética , Predisposição Genética para Doença , Óxido Nítrico Sintase Tipo III/genética , Polimorfismo de Nucleotídeo Único/genética , Alelos , Estudos de Casos e Controles , Humanos , Modelos Genéticos , Viés de Publicação , Fatores de Risco
7.
Int Heart J ; 60(3): 656-664, 2019 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-31019168

RESUMO

The issue that genetic polymorphism of tumor necrosis factor-α (TNF-α) is associated with dilated cardiomyopathy (DCM) is debatable. We sought to investigate the potential role of TNF-α gene polymorphism (G-308A) in the susceptibility to dilated cardiomyopathy.We retrieved PubMed, EMBASE, and CNKI to collect all articles which reported on the association between TNF-α G-308A polymorphism and dilated cardiomyopathy. Two authors used the Newcastle-Ottawa Scale (NOS) checklist to assess the quality of the included studies. The odds ratio (OR) with 95% confidence intervals (CI) were pooled in a specific genetic model to assess the association and Stata version 14.0 software was used.A total of 9 studies with 1338 patients and 1677 controls were included in this study. The results from this meta-analysis indicated that TNF-α G-308A polymorphism significantly increased the risk of dilated cardiomyopathy in heterozygous comparison (GA versus GG: OR = 1.87; 95%CI = 1.03-3.40; P < 0.05). The increased risk of DCM was also found in Asian populations using a dominant model and heterozygous comparison (GA+AA versus GG: OR = 2.00, 95%CI = 1.02-3.92, P < 0.05; GA versus GG: OR = 1.94, 95%CI = 1.23-3.06, P < 0.05).The current meta-analysis revealed that TNF-α gene polymorphism (G-308A) may be associated with the susceptibility to DCM.


Assuntos
Cardiomiopatia Dilatada/genética , Estudos de Associação Genética/métodos , Polimorfismo de Nucleotídeo Único , Fator de Necrose Tumoral alfa/genética , Cardiomiopatia Dilatada/etnologia , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Estudos Observacionais como Assunto
8.
Medicine (Baltimore) ; 98(9): e14716, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30817614

RESUMO

BACKGROUND: Rapid progress has been made in research of cadmium-zinc-telluride (CZT) technology in the last few years, which might serve as a new method to diagnose coronary artery disease. However, compared with coronary angiography, the diagnostic value of CZT is still controversial. We aimed to evaluate diagnosis value of coronary angiography versus CZT in coronary artery disease. METHODS: We searched the database for eligible researches associated with CZT- myocardial perfusion imaging (MPI) and invasive coronary angiography, extracted the relevant data, and rigorously screened it according to the inclusion and exclusion criteria. The accuracy indicators included sensitivity, specificity, accuracy, positive and negative likelihood ratios. RESULTS: According to the inclusion and exclusion criteria, we finally found 20 studies containing 2350 patients in this search. Pooled results showed that sensitivity of CZT-MPI was 0.84% and 95% confidence interval (95% CI): 0.78 to 0.89, specificity was 0.72, 95% CI (0.62-0.76), the specificity was lower apparently. The positive likelihood ratio was 3.0, 95% CI (2.4-3.8), the negative likelihood ratio was 0.22, 95% CI (0.16-0.31), diagnostic odds ratio was 14, 95% CI (7.84-17.42). CONCLUSION: This meta-analysis showed that CZT-MPI had satisfactory sensitivity and specificity for diagnosing coronary artery disease. Larger studies are required for further evaluation.


Assuntos
Angiografia Coronária/métodos , Doença da Artéria Coronariana/diagnóstico , Imagem de Perfusão do Miocárdio/métodos , Angiografia Coronária/normas , Doença da Artéria Coronariana/diagnóstico por imagem , Humanos , Imagem de Perfusão do Miocárdio/normas , Sensibilidade e Especificidade
9.
Exp Ther Med ; 17(2): 1321-1329, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30680009

RESUMO

In the present study, a novel p-hydroxycinnamic amide (E)-3-(4-hydroxyphenyl)-N-(4-(N-(5-meth oxypyrimidin-2-yl)-sulfamoyl)phenyl)acrylamide (HMSP) was synthesized and confirmed. In vitro cytotoxic assays indicated that HMSP was able to inhibit the proliferation of various cancer cell lines. The interaction between HMSP and human serum albumin (HSA) was examined by fluorescence, UV-Vis and circular dichroism (CD) spectra, in addition to molecular simulation. The fluorescence and UV-Vis spectra data indicated that the binding of HMSP with HSA was a static process. According to the fluorescence quenching calculation, the corresponding thermodynamic parameters, bimolecular quenching rate constant and apparent quenching constants were calculated. Van der Walls forces and hydrogen bonds were vital in the binding of HMSP on HSA. The distances between HSA and its derivatives were obtained. Furthermore, competitive experiments and molecular modeling results suggested that the binding of the compound on HSA mainly occurred in site I (sub-domain IIA). Changes in HSA conformation were observed from synchronous fluorescence and CD spectra, which were further investigated by molecular dynamic simulations.

10.
Medicine (Baltimore) ; 97(48): e13436, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30508957

RESUMO

BACKGROUND: More susceptibility genes have been proved to be associated with coronary heart disease (CHD). The goal of our study is to evaluate the association between the R262W polymorphism of SH2B3 gene and risk of CHD. METHODS: A systematic search was conducted using PubMed, Embase, Web of Science, CNKI, and WanFang databases up to March of 2018. The data of individual study were individually performed by 2 reviewers. The meta-analysis was performed by Stata software and expressed by the pooled odds ratio (OR) and the 95% confidence interval (CI), which were calculated by specific model according to heterogeneity. RESULTS: Our research was based on 12 studies involving 25,845 patients and 68,910 healthy controls. Significant association between the variant R262W and CHD were found in overall populations (OR = 1.12, 95%CI = 1.09-1.15, P = .389, I = 5.4%), but not found in Asian (OR = 1.05, 95%CI = 0.98-1.12, I = 0.0%) in subgroup analysis by ethnicity. In another subgroup analysis, when classified into CHD and myocardial infarction (MI), there was a significance association between R262W and CHD (OR = 1.11,95% CI = 1.07-1.15, I = 13.5%) and MI (OR = 1.13, 95%CI = 1.08-1.18, I = 0.0%). The Begg's funnel plot revealed no significant publication bias. CONCLUSIONS: The R262W polymorphism is associated with risk of CHD or MI in Europeans, but not in Asians.


Assuntos
Doença das Coronárias/genética , Polimorfismo de Nucleotídeo Único , Proteínas/genética , Proteínas Adaptadoras de Transdução de Sinal , Estudos de Casos e Controles , Doença das Coronárias/metabolismo , Predisposição Genética para Doença , Humanos , Peptídeos e Proteínas de Sinalização Intracelular
11.
Hypertens Res ; 41(12): 1073, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30310170

RESUMO

The authors are retracting this article [1]. In their recent work the authors have found that the degree of fibrosis in the different walls of the left atrium in pigs with hypertensive cardiomyopathy is the same. Sirius Red staining (another method to test for fibrosis) showed that there was no difference between the different walls. The authors are unable to explain this inconsistency. All authors agree with this retraction.

12.
Biol Open ; 7(1)2018 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-29212797

RESUMO

Generation of human cardiomyocytes from cells derived from various sources, including skin biopsy, has been made possible by breakthrough advances in stem cell research. However, it is attractive to build up a negligibly invasive way to create induced pluripotent stem (iPS) cells. In this study, we created iPS cells from human urine-derived epithelial cells by gene transduction using lentiviral vectors in a totally noninvasive manner. Then, we induced the differentiation of iPS cells into functional cardiomyocytes both in vitro and in vivo Action potentials were recorded in putative cardiomyocytes and spontaneous beating cells were observed. Our results offered an alternative method to generate cardiomyocytes in a totally noninvasive manner from an easily accessible source. The availability of urine and its potent reprogramming characteristics will provide opportunities for the use of cells with specific genotypes to study the pathogenesis and molecular mechanisms of disease in vitro.

13.
Medicine (Baltimore) ; 96(25): e7253, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28640127

RESUMO

BACKGROUND: Previous case-control studies on association between KCNE1 G38S polymorphism and risk of atrial fibrillation (AF) have been published but because of the conflicting results and small sample size of individual studies, the consolidated result is still controversial. OBJECTIVES: The aim of this study was to explore the relationship between KCNE1 G38S polymorphism and risk of AF. METHODS: We performed a comprehensive literature search on PubMed, Embase, OVID, Web of Science, Wan Fang, and CNKI databases up to March 10, 2017 in English and Chinese languages. Two of the authors individually extracted study data and assessed the study quality using Newcastle-Ottawa scale. Odds ratios (ORs) and 95% confidence intervals (CIs) were combined in different genetic models for evaluation using a random-effect model or fixed-effect model according to interstudy heterogeneity. RESULTS: There were totally 14 independent case-control studies of 2810 patients and 3080 healthy controls included. Significant associations were found between KCNE1 G38S polymorphism and AF in overall population under all genetic models: allelic (OR: 1.34, 95% CI: 1.24-1.45, P < .001), homozygous (OR: 1.90, 95% CI: 1.61-2.24, P < .001), heterozygous (OR: 1.43, 95% CI: 1.21-1.68, P < .001), recessive (OR: 1.42, 95% CI: 1.20-1.69, P < .001), dominant genetic model (OR: 1.62, 95% CI: 1.39-1.89, P < .001). Subgroup analyses indicated similar association in Chinese and white. CONCLUSIONS: The G38S polymorphism in the KCNE1 gene can significantly increase the risk of AF in both Chinese and white.


Assuntos
Fibrilação Atrial/genética , Predisposição Genética para Doença , Polimorfismo Genético , Canais de Potássio de Abertura Dependente da Tensão da Membrana/genética , Fibrilação Atrial/etnologia , Humanos
14.
Medicine (Baltimore) ; 96(24): e7179, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28614256

RESUMO

Recently a large number of investigations have implicated the association between the chemokine CXC ligand 12 gene polymorphism (rs1746048) and risk of coronary heart disease (CHD), but the results remain debatable. The aim of our study was to provide more compelling evidence for the relationship between rs1746048 and CHD risk. Studies eligible for this meta-analysis were identified through electronic search of PubMed, EMBASE, and CNKI. Two authors performed independent literature review and study quality assessment by using the Newcastle-Ottawa Scale checklist. The odds ratios (ORs) with 95% confidence intervals (CIs) were pooled in a specific genetic model to assess the association. The meta-analysis of 48,852 patients and 64,386 controls from 12 studies showed that patients with rs1746048 had 1.11 times of high risk in developing CHD (OR = 1.11; 95% CI = 1.09-1.14; P < .005; I = 35.8%). The increased risk of CHD was also found in both Asian (OR = 1.07; 95%CI = 1.02-1.12; P < .005; I = 40.6%) and Caucasian populations (OR = 1.14; 95% CI = 1.10-1.18; P < .005; I = 22.2%). The results of our meta-analysis suggested that chemokine CXC ligand 12 gene polymorphism (rs1746048) may be linked with susceptibility to CHD.


Assuntos
Quimiocina CXCL12/genética , Doença das Coronárias/genética , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único , Doença das Coronárias/etnologia , Humanos , Estudos Observacionais como Assunto
15.
Hypertens Res ; 40(5): 450-456, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28003648

RESUMO

Heart failure with preserved ejection fraction (HFpEF), which is a primary driver of morbidity and mortality, accounts for approximately half of all heart failure cases. Therefore, it is essential to develop preclinical animal models for HFpEF pharmacological treatment strategies. We created a porcine model of severe hypertension and hyperlipidemia by using a combination of deoxycorticosterone acetate (DOCA, 100 mg kg-1), Western diet (WD) and angiotensin II infusion. Systolic blood pressure, echocardiography and invasive pressure-volume loop were assessed at baseline, 12 weeks and 18 weeks. A detailed histological assessment was also performed to determine the cardiac structural remodeling. Compared with controls (n=10), hypertensive animals (n=10) showed markedly higher systolic blood pressure (181 vs. 86 mm Hg) at 18 weeks. Concentric remodeling, characterized by a normal chamber size with a thicker wall, was observed in hypertensive animals. Left ventricle diastolic function showed a tendency toward decline, according to the echocardiographic data. Hemodynamic data showed that the end-diastolic pressure-volume relationship was elevated without changes in the end-systolic pressure-volume relationship. Histological results revealed that the fibrotic area in hypertensive animals (P<0.05 vs. controls) and the fibrotic area in the posterior wall of hypertensive animals' left atria were larger than other sites of the left atria (P<0.05 vs. other sites). This model can mimic clinical HFpEF to some degree. We found that the posterior wall of the left atrium is more susceptible to atrial remodeling associated with hypertension compared with other regions of the left atrium.


Assuntos
Cardiomiopatias/patologia , Hipertensão/patologia , Miocárdio/patologia , Animais , Cardiomiopatias/diagnóstico por imagem , Acetato de Desoxicorticosterona , Dieta Hiperlipídica , Ecocardiografia , Feminino , Fibrose/patologia , Hemodinâmica , Hiperlipidemias/induzido quimicamente , Hiperlipidemias/complicações , Hiperlipidemias/patologia , Hipertensão/diagnóstico por imagem , Suínos
16.
Huan Jing Ke Xue ; 37(11): 4428-4436, 2016 Nov 08.
Artigo em Chinês | MEDLINE | ID: mdl-29964701

RESUMO

In the present study, nonylphenol (NP) was selected as the target pollutant to investigate the effect of biochar produced from wheat residue at different temperatures on loess soil based on the batch experiments. The research basically included adsorption kinetic, thermodynamic and some influencing factors such as biochar with different pyrolysis temperature, particle size and pH value. The results showed that the adsorption reaction of NP onto loess soil without biochar was 10 h during fast reaction, and after the addition of biochar into loess soil, the fast reaction time of NP adsorption was shortened. Meanwhile, in the fast stage the adsorption reaction of NP onto loess soil with biochar was significantly higher than loess soil without biochar, while the difference of adsorption capacity was small at different carbonization temperatures. The adsorption reaction of NP onto loess soil by adding biochar could be well described by the pseudo-second-order kinetics model and reached equilibrium in 16 h. The kinetic data showed that the adsorption of NP accorded well with the Freundlich isotherm model. The saturated adsorption capacity was improved as temperature increased with or without biochar. Thermodynamic parameter analysis indicated Gibbs free energy ΔGθ<0, entropy ΔHθ>0 and enthalpy ΔSθ>0, demonstrating it was a spontaneous, endothermic and chaos-increasing adsorption process. At the same temperature, the adsorption capacity of NP in loess soils increased dramatically with the increase of carbonization temperature. The smaller particle size of the loess with the addition of biochar, the better the adsorption of NP. When the pH value was 4 to 7, the adsorption capacity of NP onto loess soil by adding biochar showed an increasing trend; in the pH range of 7 to 10, the adsorption saturation capacity decreased with the increase of pH value. Therefore, the adsorption of NP on loess with the addition of biochar had the best adsorption effect in the neutral range. Acid and alkalinity were not conducive to the adsorption of NP.


Assuntos
Carvão Vegetal/química , Fenóis/química , Solo/química , Adsorção , China , Concentração de Íons de Hidrogênio , Cinética , Temperatura , Termodinâmica
17.
Huan Jing Ke Xue ; 37(9): 3453-3459, 2016 Sep 08.
Artigo em Chinês | MEDLINE | ID: mdl-29964780

RESUMO

In order to study the adsorption behavior of organic pollutants in sediment of the Yellow River in Lanzhou, p-hydroxy biphenyl (PHB) was selected as the typical organic pollutants to understand the adsorption kinetics and thermodynamics of PHB onto sediment of the Yellow River in Lanzhou based on the batch experiments. Meanwhile, the effects of systemic temperature, such as the particle size, the initial concentration of PHB, pH value, and the ionic strength, were also investigated for the adsorption of PHB onto sediment of the Yellow River. The results indicated that the adsorption kinetics of PHB onto sediment of the Yellow River could be better described by Pseudo-second-order model, and the boundary layer and intraparticle diffusion were both involved in the adsorption kinetic process. The adsorption thermodynamics of PHB onto sediment of the Yellow River were fitted well with the Langmuir model(R2>0.974), which was a single molecular layer adsorption process. The average adsorption free energy E ranged from 0.913 to 1.00 kJ·mol-1 when the systemic temperatures increased from 25℃ to 45℃, suggesting a physical adsorption. Thermodynamic parameter analysis indicated that Gibbs free energy (ΔGθ) and Entropy (ΔHθ) were less than zero, but Enthalpy (ΔSθ) was more than zero in the adsorption process, which tended to prove the spontaneous nature of the adsorption process, the endothermic nature of the adsorption process and the increased randomness at the sediment surface. Furthermore, the smaller the particle size, the greater the adsorption capacity of the PHB. The adsorption capacity was increased with the increase of the initial concentration of PHB. When the pH value in a range of 4.23 to 7.00, the adsorption capacity of PHB showed a slow decreasing trend, while the decreasing was sharp when pH value was greater than 7.00, and the adsorption capacity was almost zero when pH value was about 10.3. With the increase of ionic strength, the adsorption amount of PHB was also increased, but when the ionic strength increased to a certain value, due to the competitive adsorption, the adsorption of PHB onto sediments would be inhibited, resulting in decreased amount of adsorption.

18.
Huan Jing Ke Xue ; 37(12): 4857-4866, 2016 Dec 08.
Artigo em Chinês | MEDLINE | ID: mdl-29965329

RESUMO

The primary objective of this study was to investigate the effect of biochar, produced from maize and pine needles residue at different temperatures, on the adsorption of diuron onto loess soil. Meanwhile, the effect of the systemic temperature, pH values and the initial concentration of diuron were also investigated for the adsorption of diuron onto losses soil. And Kinetic parameters, such as rate constants, equilibrium adsorption capacities and related correlation coefficients were also calculated and discussed. The results showed that the adsorption of diuron onto loess soil by adding biochar could be described by the pseudo-second-order kinetic model, and followed the intraparticle diffusion model, but diffusion was not only the rate-controlling step. The adsorption process was divided into fast (0-8 h) and slow (8-12 h) adsorption stages, and equilibrium was reached at around 12 h. The adsorption thermodynamics of diuron onto loess soil was nonlinear by nature, and well fitted with the Freundlich isothermal model. Thermodynamic parameter analysis of diuron onto loess soil by adding biochar showed that Gibbs free energy (ΔGθ) was less than zero, while Enthalpy (ΔSθ) and Entropy (ΔHθ) were greater than zero, indicating a spontaneous endothermic adsorption, which increased the degree of disorder during the process. And Thermodynamic parameter analysis of diuron onto loess soil without adding biochar showed that Gibbs free energy (ΔGθ) and Entropy (ΔHθ) were less than zero, while Enthalpy (ΔSθ) was greater than zero. The average adsorption free energy E was in range of 1.29-5.00 kJ·mol-1 when the temperatures increased from 25 to 45℃, indicated that adsorption of diuron onto loess was a physical adsorption. The results also suggested that the influencing factors of diuron had significant effects on the adsorptive behaviors of diuron on loess soil. With increasing pyrolysis temperature of biochar, the equilibrium concentration of diuron in water decreased, while the amount of adsorption on loess soil increased. When the initial concentration of diuron increased from 0.5 mg·L-1 to 6 mg·L-1, the adsorption capacity of diuron onto loess soil by adding biochar showed a rapidly increasing trend. When the initial concentration increased. the adsorption capacity showed a slow increasing trend and gradually tended to be stable. In the pH range of 3 to 10, the adsorption capacity of diuron onto loess soil by adding biochar changed a little.


Assuntos
Carvão Vegetal , Diurona/análise , Solo/química , Temperatura , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Pinus , Termodinâmica , Zea mays
19.
Environ Geochem Health ; 38(1): 243-53, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25980560

RESUMO

The primary objective of this study was to investigate the effect of biochar, produced from wheat residue at different temperatures, on the adsorption of diesel oil by loess soil. Kinetic and equilibrium data were processed to understand the adsorption mechanism of diesel by biochar-affected loess soil; dynamic and thermodynamic adsorption experiments were conducted to characterize this adsorption. The surface features and chemical structure of biochar, modified at varying pyrolytic temperatures, were investigated using surface scanning electron microscopy and Fourier transform infrared analysis. The kinetic data showed that the adsorption of diesel oil onto loess soil could be described by a pseudo-second-order kinetic model, with the rate-controlling step being intraparticle diffusion. However, in the presence of biochar, boundary layer control and intraparticle diffusion were both involved in the adsorption. Besides, the adsorption equilibrium data were well described by the Freundlich isothermal model. The saturated adsorption capacity weakened as temperature increased, suggesting a spontaneous exothermic process. Thermodynamic parameter analysis showed that adsorption was mainly a physical process and was enhanced by chemical adsorption. The adsorption capacity of loess soil for diesel oil was weakened with increasing pH. The biochar produced by pyrolytic wheat residue increased the adsorption behavior of petroleum pollutants in loess soil.


Assuntos
Carvão Vegetal/química , Gasolina/análise , Temperatura Alta , Incineração , Poluentes do Solo/química , Adsorção , China , Cinética , Triticum/química
20.
Asian Pac J Cancer Prev ; 16(16): 7205-10, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26514513

RESUMO

BACKGROUND: In this study, influence caused by expression plasmids of connective tissue growth factor (CTGF) and tissue inhibitor of metalloproteinase-1 (TIMP-1) short hairpin RNA (shRNA) on mRNA expression of CTGF,TIMP-1,procol-α1 and PCIII in hepatic tissue with hepatic fibrosis, a precancerous condition, in rats is analyzed. MATERIALS AND METHODS: To screen and construct shRNA expression plasimid which effectively interferes RNA targets of CTGF and TIMP-1 in rats. 50 cleaning Wistar male rats are allocated randomly at 5 different groups after precancerous fibrosis models and then injection of shRNA expression plasimids. Plasmid psiRNA-GFP-Com (CTGF and TIMP-1 included), psiRNA-GFP-CTGF, psiRNA-GFP-TIMP-1 and psiRNA- DUO-GFPzeo of blank plasmid are injected at group A, B, C and D, respectively, and as model control group that none plasimid is injected at group E. In 2 weeks after last injection, to hepatic tissue at different groups, protein expression of CTGF, TIMP-1, procol-α1and PC III is tested by immunohistochemical method and,mRNA expression of CTGF,TIMP-1,procol-α1 and PCIII is measured by real-time PCR. One-way ANOVA is used to comparison between-groups. RESULTS: Compared with model group, there is no obvious difference of mRNA expression among CTGF,TIMP-1,procol-α1,PC III and of protein expression among CTGF, TIMP-1, procol-α1, PC III in hepatic tissue at group injected with blank plasmid. Expression quantity of mRNA of CTGF, TIMP-1, procol-α1 and PCIII at group A, B and C decreases, protein expression of CTGF, TIMP-1, procol-α1, PC III in hepatic tissue is lower, where the inhibition of combination RNA interference group (group A) on procol-α1 mRNA transcription and procol-α1 protein expression is superior to that of single interference group (group B and C) (P<0.01 or P<0.05). CONCLUSIONS: RNA interference on CTGF and/or TIMP-1 is obviously a inhibiting factor for mRNA and protein expression of CTGF, TIMP-1, procol-α1 and PCIII. Combination RNA interference on genes of CTGF and TIMP-1 is superior to that of single RNA interference, and this could be a contribution for prevention of precancerous condition.


Assuntos
Fator de Crescimento do Tecido Conjuntivo/antagonistas & inibidores , Cirrose Hepática/prevenção & controle , Plasmídeos/administração & dosagem , Lesões Pré-Cancerosas/prevenção & controle , RNA Interferente Pequeno/genética , Inibidor Tecidual de Metaloproteinase-1/antagonistas & inibidores , Animais , Fator de Crescimento do Tecido Conjuntivo/genética , Cirrose Hepática/genética , Cirrose Hepática/patologia , Masculino , Lesões Pré-Cancerosas/genética , Lesões Pré-Cancerosas/patologia , RNA Mensageiro/genética , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase em Tempo Real , Inibidor Tecidual de Metaloproteinase-1/genética
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