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1.
Anal Chem ; 91(21): 13433-13438, 2019 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-31571483

RESUMO

Proton transport plays an important role in many biological and technological processes. Numerous experiments and molecular dynamics simulations have proved the increase of proton mobility in confined nanostructures. In this work, we studied the proton transport across flow-through silica nanochannel membranes (SNMs) with vertically aligned channels, uniform diameter (∼2.3 nm), high porosity (16.7%), and ultrasmall thickness (88 nm). Taking into account both the mutual interaction between nanochannels and the contribution of surface conductance, a new theoretical model of ion conductance for SNMs was derived by modifying the conductance model reported previously with a correction factor. The correction factor was estimated by closely matching the experimental conductance of SNMs in KCl and NaCl solutions with the theoretical one calculated by the model. Then the measured conductance of SNMs in HCl solutions was found to be at least four times higher than the calculated value by the model. Given the total conductance across SNMs is dominated by the access conductance instead of channel conductance, the difference between experimental and theoretical conductance values implies either that the theoretical model does not capture the real physics of access conductance or that the two-dimensional nanoconfinement effect exists at the nanochannel entrances. The latter effect likely arises from mutual interaction of neighboring nanochannel entrances.

2.
J Am Chem Soc ; 140(46): 15904-15915, 2018 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-30380848

RESUMO

Electrochemiluminescence (ECL) is a highly successful technique used in commercial immunoassays for clinical diagnosis. Developing an ECL-based multiplex immunoassay, with the potential to enable high-throughput detection of multiple biomarkers simultaneously, remains a current research interest yet is limited by a narrow choice of ECL luminophores. Herein we report the synthesis, photophysics, electrochemistry, and ECL of several new ruthenium(II) and iridium(III) complexes, three of which are eventually used as signal reporters for multiplex immunoassay. The ECL behaviors of individual luminophores and their mixtures were investigated in multiple modes, including light intensity, spectrum, and image measurements. The spectral peak separation between Ru(bpy)2(dvbpy)2+ (bpy = 2,2'-bipyridine, dvbpy = 4,4'-bis(4-vinylphenyl)-2,2'-bipyridine), and Ir(dFCF3ppy)2(dtbbpy)+ (dFCF3ppy = 3,5-difluoro-2-[5-(trifluoromethyl)-2-pyridinyl]phenyl, dtbbpy = 4,4'-bis( tert-butyl)-2,2'-bipyridine) was up to 145 nm, thus providing the spectrum-resolved possibility of identifying light signals. The potential-resolved ECL signals were achieved for the mixtures of Ir(ppy)3 (ppy = 2-phenylpyridine) with either Ru(bpy)2(dvbpy)2+ or Ir(dFCF3ppy)2(dtbbpy)+, due to the self-annihilation ECL of Ir(ppy)3 at higher potentials, as confirmed by electrochemistry-coupled mass spectrometry. A multiplex immunoassay free of spatial spotting antibodies on plates or substrates was ultimately devised by combining luminophore-loaded polymer beads with the homogeneous sandwich immunoreaction. Using potential and spectrum dual-resolved ECL as the readout signal, simultaneous recognition of three antigens, namely, carcinoembryonic antigen (CEA), alpha-fetoprotein (AFP), and beta-human chorionic gonadotropin (ß-HCG), was demonstrated in a single run for a sample volume of 300 µL. These results contribute to the understanding of ECL generation by multiple luminophores and devising spot-free multiplex immunoassays with less sample consumption.


Assuntos
Antígeno Carcinoembrionário/análise , Gonadotropina Coriônica/análise , Técnicas Eletroquímicas , Imunoensaio , Medições Luminescentes , alfa-Fetoproteínas/análise , Complexos de Coordenação/química , Humanos , Irídio/química , Rutênio/química
4.
Pediatr Cardiol ; 35(4): 711-8, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24272170

RESUMO

It is documented that exercise can increase serum cardiac troponins in adults and adolescents; however, there is a lack of related studies concerning the release of cardiac troponins in children. This study investigated the influence of table tennis training on cardiac biomarkers in children. Twenty-eight male children performed six 10-min forehand exercise sessions with 5-min recovery intervals. Serum cardiac troponin T (cTnT) and I (cTnI), and creatinine kinase isoenzyme MB (CK-MB) were assessed before exercise, immediately after the last 10 min of exercise (PEI), 4 h post-exercise (PE4), 24 h post-exercise (PE24), and 48 h post-exercise (PE48). Cardiac function was measured using an ultrasound system (GE Vivid7 Dimension) at rest state. Serum cTnT, cTnI, and CK-MB were significantly elevated from the PEI sample point, and returned to baseline at the PE48 sample point in children. Serum cTnT in four (14.29%), nine (32.14%), and two (7.14%) subjects at the PEI, PE4, and PE24 sample points, respectively, exceeded the cutoff for myocardial injury. At the PE4 sample point, cTnT in five subjects (17.86%) exceeded the cutoff for acute myocardial infarction. Serum cTnI in two (14.29%), seven (25%), and two (7.14 %) subjects at the PEI, PE4, and PE24 timepoints, respectively, exceeded the cutoff for myocardial injury. cTnI in two subjects (7.14%) exceeded the cutoff for acute myocardial infarction at the PE4 timepoint in children. Repeated bouts of table tennis forehand training can significantly increase the release of serum cardiac troponins in some children.


Assuntos
Atletas , Biomarcadores/sangue , Isquemia Miocárdica/sangue , Aptidão Física , Tênis/fisiologia , Criança , Creatina Quinase Forma MB/sangue , Ecocardiografia , Seguimentos , Humanos , Masculino , Isquemia Miocárdica/diagnóstico , Isquemia Miocárdica/fisiopatologia , Valor Preditivo dos Testes , Valores de Referência , Reprodutibilidade dos Testes , Troponina/sangue
5.
Anaerobe ; 16(4): 402-4, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20452448

RESUMO

Fusobacterium necrophorum is the main pathogen that causes numerous necrobacilloses. Hemolysin is one of the major virulence factors involved in fusobacterial infections. In order to investigate the genetic basis of hemolytic activity and the regulation mechanism of the hemolysin expression, a genomic library was constructed from F. necrophorum DNA by ligating DNA fragments generated by partial HindIII digestion with pUC18 vector. The screening of the genomic library with polymerase chain reaction, DNA sequencing and sequence assembly led to a 7.45 kb sequence which includes the putative hly gene and upstream sequence. Clustered putative genes encoding short chain acyl-CoA dehydrogenase (Scad) and electron transfer flavoprotein (Etf) alpha and beta subunits locate upstream of hly. A 535 bp non-coding sequence, possibly with some cis-regulatory elements involved in the regulation of the hemolysin expression in F. necrophorum, locates between etf-beta and hly. The nucleotide sequence of the hly gene indicates it encodes hemolysin. It is the first characterized hemolysin coding gene in F. necrophorum.


Assuntos
DNA Bacteriano/genética , Fusobacterium necrophorum/genética , Proteínas Hemolisinas/biossíntese , Proteínas Hemolisinas/genética , Sequência de Aminoácidos , Biblioteca Gênica , Ordem dos Genes , Genes Bacterianos , Dados de Sequência Molecular , Análise de Sequência de DNA
6.
Chemosphere ; 104: 1-6, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24287266

RESUMO

Aluminum (Al) is present in the daily life of all humans. With the incidence of Al contamination increased in recent years, the toxicity of Al on the immune function has attracted more attention. Even with this increased attention, the mechanism of Al immunotoxicity still remains unclear. The mechanism of Al immunotoxicity reviewed herein focused on the effects of Al on the splenic trace elements, the status of α-naphthyl acetate esterase (ANAE) cells, cytokines, complement and immunoglobulins, as well as macrophages. The studies in the literature showed that Al decreased splenic iron (Fe) and zinc (Zn) levels, but the effects of Al on splenic copper (Cu) level was ambiguous and controversial. Al exposure inhibited levels of ANAE(+) cells, the production of interleukin (IL)-2 and the functions of macrophages. With respect to other key cytokines, studies showed that Al suppressed the production of tumor necrosis factor (TNF)-α in vitro; effects of Al on TNF-α formation in vivo were less overt. Al exposure reduced complement 3 (C3) level, but effects of Al exposure on complement 4 (C4) level were not as clear-cut. Lastly, the effects of Al exposure on the IgG, IgM and IgA levels were conflicting. Taken in totality, the results of several studies in the literature demonstrated that Al could impart adverse effects on immune function.


Assuntos
Alumínio/imunologia , Alumínio/toxicidade , Animais , Cobre/imunologia , Citocinas/imunologia , Humanos , Ferro/imunologia , Baço/efeitos dos fármacos , Baço/imunologia , Oligoelementos/imunologia , Fator de Necrose Tumoral alfa/imunologia
7.
Hepatol Int ; 8(3): 425-35, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26202644

RESUMO

AIM: The aim of this study is to investigate the effect of pre-endurance training on the prevention of alcohol-induced acute hepatic injury and on hepatic mitophagy. METHODS: Forty-eight male Sprague-Dawley rats were randomly divided into four groups: (1) control group, (2) 12-week exercise training group, (3) 5-day alcohol intake group, and (4) 12-week exercise training plus 5-day alcohol intake group. The rats were examined to determine the following: BCL2/adenovirus E1B 19 kDa protein-interacting protein 3 (BNIP3), hypoxia-inducible factor-1α (HIF-1α), cytochrome P450 2E1 (CYP2E1), alcohol dehydrogenase (ADH), microtubule-associated protein 1 light chain 3 (LC3II), Beclin1 mRNA and protein expressions, mitochondrial reactive oxygen species (ROS) production, mitochondrial thiobarbituric acid-reactive substances (TBARS) level, aconitase and ATP synthase activities, mitochondrial inner membrane potential, NADH/NAD(+) ratio, triglyceride (TG), the number of mtDNA and mitochondrial respiration functions in liver tissue, and serum ALT and AST. RESULTS: Pre-endurance training attenuated acute alcohol treatment-induced increase in mitochondrial TBARS, ROS production, NADH/NAD(+) ratio, state 4 respiration rate, TG, serum ALT and AST, as well as BNIP3, HIF-1α, LC3II, and Beclin 1 mRNA and protein levels, however, CYP2E1 and ADH mRNA and protein levels unchanged. Meanwhile, it attenuated the acute alcohol intake-induced decrease in aconitase activity, inner mitochondrial membrane potential (Δψ), ATP synthase activity, state 3 respiration rate, respiratory control ratio, and the number of mtDNA. CONCLUSION: Pre-endurance training can decrease acute alcohol intake-induced damaged mitochondria accumulation and reduced acute alcohol intake-induced mitophagy, which built a new balance between mitophagy and damaged mitochondria accumulation.

8.
Bing Du Xue Bao ; 26(3): 238-43, 2010 May.
Artigo em Zh | MEDLINE | ID: mdl-20572347

RESUMO

Bovine viral diarrhea virus (BVDV) is a member of the genus Pestivirus, which is a widespread problem for beef and dairy herds, and has given rise to a significant loss in the livestock industry all over the world. The BVDV strain JZ05-1 isolated from cattle in Jilin, China generated cytopathic effect (CPE) in MDBK cells. Eight overlapped gene fragments were amplified by RT-PCR and sequenced, the complete genom sequence of BVDV strain JZ05-1 was assembled. According to the results, the JZ05-1 genome was composed of 12285 nucleotides in length (GenBank accession No. GQ888686), which could be divided into three regions: a 387 nt 5'-untranslated region (UTR), a 11694 nt single large open reading frame encoding a polyprotein, and a 204 nt 3'-UTR. The 5'-UTR and genome sequences were analyzed by sequence alignment and construction of phylogenetic trees. The strain JZ05-1 was classified as BVDV type 2a. The BVDV-2 strain JZ05-1 genome showed high similarity to the p11Q isolated in Canada and the XJ-04 isolated in China, with 90% and 91% identity in nucleotide sequence, respectively. Compared with the similarity within the BVDV-2 genotype (96%), the JZ05-1 had low sequence similarity to other BVDV-2 strains.


Assuntos
Vírus da Diarreia Viral Bovina Tipo 2/genética , Vírus da Diarreia Viral Bovina Tipo 2/isolamento & purificação , Genoma Viral/genética , Regiões 5' não Traduzidas/genética , Animais , Bovinos , China , Vírus da Diarreia Viral Bovina Tipo 2/classificação , Genótipo , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA
9.
Asia Pac J Clin Nutr ; 16 Suppl 1: 193-5, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17392103

RESUMO

This study was designed to determine whether combined treatments with soybean isoflavone dosage and moderate exercise would exhibit synergistically effects on bone metabolism following the onset of menopause. Fifty 12 wk-old female Wistar rats were assigned to five groups: 1) Sham operated (Sham), 2) ovariectomized (OVX), 3) OVX received soybean isoflavone (OVX-IF), 4) OVX exercised (OVX-EXE) and 5) OVX treated with both soybean isoflavone and exercise (OVX-IF-EXE). All rats were fed a normal diet ad libitum. Daily soybean isoflavone dosage was 50 mg/kg body weight. The vehicle was given in Sham, OVX and OVX-EXE groups. The drugs were all oral administered using a stomach tube. Exercising rats were trained on an uphill treadmill at 20 m/min for 1h/day, 5 days/week. The experimental duration consisted of the adaptation periods of 2 weeks and treatment periods of 8 weeks. The results showed that the uterus relative weights in OVX-EXE, OVX-IF and OVX-IF-EXE groups were all lower than those in Sham, they were higher than those in the OVX group. Serum alkaline phosphates (AKP) activities of OVX was significantly increased as compared to that of Sham (p<0.01). OVX-IF and OVX-IF-EXE respectively decreased the Serum alkaline phosphates activities, as compared to that of OVX (p<0.01). The tartrate-resistant acid phosphatase (TRAP) value of OVX was significantly increased as compared to that of Sham (p<0.05). OVX-IF decreased the TRAP as compared to that of OVX (p<0.05). These results suggest soybean isoflavone and resistance exercise both can restrain ovx-induced bone loss. But their mechanisms may be different.


Assuntos
Densidade Óssea/efeitos dos fármacos , Osso e Ossos , Glycine max/química , Isoflavonas/farmacologia , Osteoporose/prevenção & controle , Condicionamento Físico Animal/fisiologia , Fosfatase Alcalina/sangue , Fosfatase Alcalina/metabolismo , Animais , Biomarcadores/sangue , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/metabolismo , Relação Dose-Resposta a Droga , Feminino , Tamanho do Órgão/efeitos dos fármacos , Ovariectomia , Distribuição Aleatória , Ratos , Ratos Wistar
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