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1.
Molecules ; 29(10)2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38792181

RESUMO

This study investigates the utilisation of organometallic network frameworks composed of fourth-period transition metals and tetrahydroxyquinone (THQ) in electrocatalytic CO2 reduction. Density functional theory (DFT) calculations were employed in analysing binding energies, as well as the stabilities of metal atoms within the THQ frameworks, for transition metal TM-THQs ranging from Y to Cd. The findings demonstrate how metal atoms could be effectively dispersed and held within the THQ frameworks due to sufficiently high binding energies. Most TM-THQ frameworks exhibited favourable selectivity towards CO2 reduction, except for Tc and Ru, which experienced competition from hydrogen evolution reaction (HER) and required solution environments with pH values greater than 5.716 and 8.819, respectively, to exhibit CO2RR selectivity. Notably, the primary product of Y, Ag, and Cd was HCOOH; Mo produced HCHO; Pd yielded CO; and Zr, Nb, Tc, Ru, and Rh predominantly generated CH4. Among the studied frameworks, Zr-THQ displayed values of 1.212 V and 1.043 V, corresponding to the highest limiting potential and overpotential, respectively, while other metal-organic frameworks displayed relatively low ranges of overpotentials from 0.179 V to 0.949 V. Consequently, it is predicted that the TM-THQ framework constructed using a fourth-period transition metal and tetrahydroxyquinone exhibits robust electrocatalytic reduction of CO2 catalytic activity.

2.
Molecules ; 29(12)2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38930961

RESUMO

Metal-organic frameworks have demonstrated great capacity in catalytic CO2 reduction due to their versatile pore structures, diverse active sites, and functionalization capabilities. In this study, a novel electrocatalytic framework for CO2 reduction was designed and implemented using 2D coordination network-type transition metal-hexahydroxytricyclic quinazoline (TM-HHTQ) materials. Density functional theory calculations were carried out to examine the binding energies between the HHTQ substrate and 10 single TM atoms, ranging from Sc to Zn, which revealed a stable distribution of metal atoms on the HHTQ substrate. The majority of the catalysts exhibited high selectivity for CO2 reduction, except for the Mn-HHTQ catalysts, which only exhibited selectivity at pH values above 4.183. Specifically, Ti and Cr primarily produced HCOOH, with corresponding 0.606 V and 0.236 V overpotentials. Vanadium produced CH4 as the main product with an overpotential of 0.675 V, while Fe formed HCHO with an overpotential of 0.342 V. Therefore, V, Cr, Fe, and Ti exhibit promising potential as electrocatalysts for carbon dioxide reduction due to their favorable product selectivity and low overpotential. Cu mainly produces CH3OH as the primary product, with an overpotential of 0.96 V. Zn primarily produces CO with a relatively high overpotential of 1.046 V. In contrast, catalysts such as Sc, Mn, Ni, and Co, among others, produce multiple products simultaneously at the same rate-limiting step and potential threshold.

3.
J Cardiovasc Magn Reson ; 24(1): 61, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-36451198

RESUMO

BACKGROUND: Cardiovascular magnetic resonance (CMR) offers comprehensive right ventricular (RV) evaluation in pulmonary arterial hypertension (PAH). Emerging four-dimensional (4D) flow CMR allows visualization and quantification of intracardiac flow components and calculation of phasic blood kinetic energy (KE) parameters but it is unknown whether these parameters are associated with cardiopulmonary exercise test (CPET)-assessed exercise capacity, which is a surrogate measure of survival in PAH. We compared 4D flow CMR parameters in PAH with healthy controls, and investigated the association of these parameters with RV remodelling, RV functional and CPET outcomes. METHODS: PAH patients and healthy controls from two centers were prospectively enrolled to undergo on-site cine and 4D flow CMR, and CPET within one week. RV remodelling index was calculated as the ratio of RV to left ventricular (LV) end-diastolic volumes (EDV). Phasic (peak systolic, average systolic, and peak E-wave) LV and RV blood flow KE indexed to EDV (KEIEDV) and ventricular LV and RV flow components (direct flow, retained inflow, delayed ejection flow, and residual volume) were calculated. Oxygen uptake (VO2), carbon dioxide production (VCO2) and minute ventilation (VE) were measured and recorded. RESULTS: 45 PAH patients (46 ± 11 years; 7 M) and 51 healthy subjects (46 ± 14 years; 17 M) with no significant differences in age and gender were analyzed. Compared with healthy controls, PAH had significantly lower median RV direct flow, RV delayed ejection flow, RV peak E-wave KEIEDV, peak VO2, and percentage (%) predicted peak VO2, while significantly higher median RV residual volume and VE/VCO2 slope. RV direct flow and RV residual volume were significantly associated with RV remodelling, function, peak VO2, % predicted peak VO2 and VE/VCO2 slope (all P < 0.01). Multiple linear regression analyses showed RV direct flow to be an independent marker of RV function, remodelling and exercise capacity. CONCLUSION: In this 4D flow CMR and CPET study, RV direct flow provided incremental value over RVEF for discriminating adverse RV remodelling, impaired exercise capacity, and PAH with intermediate and high risk based on risk score. These data suggest that CMR with 4D flow CMR can provide comprehensive assessment of PAH severity, and may be used to monitor disease progression and therapeutic response. TRIAL REGISTRATION NUMBER: https://www. CLINICALTRIALS: gov . Unique identifier: NCT03217240.


Assuntos
Hipertensão Arterial Pulmonar , Humanos , Hipertensão Arterial Pulmonar/diagnóstico por imagem , Valor Preditivo dos Testes , Ventrículos do Coração , Biomarcadores , Remodelação Ventricular , Espectroscopia de Ressonância Magnética
4.
Heart Lung Circ ; 31(1): 128-135, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34116941

RESUMO

BACKGROUND: Paradoxical low-flow (LF) severe aortic stenosis (AS) despite preserved left ventricular (LV) ejection fraction (LVEF) has been shown to be distinct from normal-flow (NF) AS, with a poorer prognosis. Relative valve load (RVL) is a novel echocardiographic haemodynamic index based on the ratio of transaortic mean pressure gradient to the global valvulo-arterial impedance (Zva) in order to estimate the contribution of the valvular afterload to the global LV load. We aimed to determine the usefulness of RVL in LF AS versus NF AS. METHOD: A total of 450 consecutive patients with medically managed severe AS (aortic valve area <1.0 cm2) with preserved LVEF (>50%) were studied. Patients were divided into LF (stroke volume index <35 mL/m2) or NF, and high RVL or low RVL. Baseline clinical and echocardiographic profiles, as well as clinical outcomes, were compared. RESULTS: There were 149 (33.1%) patients with LF. Despite higher global impedance in LF (Zva 6.3±2.4 vs 3.9±0.9 mmHg/mL/m2; p<0.001) compared with NF, the RVL in LF AS was significantly lower (5.4±2.7 vs 9.8±5.1 mL/m2; p<0.001). On multivariable analysis, low RVL (≤7.51) remained independently associated with poor clinical outcomes on Cox regression (hazard ratio, 1.31; 95% confidence interval, 1.03-1.68), with 53.2% sensitivity and 70.3% specificity. This was comparable to other prognostic indices in AS. Kaplan-Meier curves demonstrated that low RVL was associated with increased mortality. CONCLUSIONS: Increased systemic arterial afterload may be important in the pathophysiology of LF AS. Low RVL was an independent predictor of poor clinical outcomes in medically managed severe AS. There may be a greater role in the attenuation of systemic arterial afterload in AS to improve outcomes.


Assuntos
Estenose da Valva Aórtica , Função Ventricular Esquerda , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/cirurgia , Estenose da Valva Aórtica/diagnóstico , Estenose da Valva Aórtica/cirurgia , Humanos , Estudos Retrospectivos , Índice de Gravidade de Doença , Volume Sistólico
5.
Medicina (Kaunas) ; 58(7)2022 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-35888687

RESUMO

Currently, no consensus exists regarding Sotos syndrome in the Chinese population. Here, we present a case of neonatal Sotos syndrome, followed by a retrospective analysis of five cases of neonatal Sotos syndrome, reported in China. The study subject was a twin premature infant, heavier than gestational age, with characteristic facial features, limb shaking, and hypertonia. Transient hypoglycemia, abnormal cranial magnetic resonance imaging, multiple nodules in polycystic kidneys and liver, abnormal hearing, patent ductus arteriosus, and an atrial septal defect were also noted. The subject showed overgrowth and developmental retardation at 3 months of age. Sequencing revealed a novel missense mutation, c.5000C>A, in the nuclear receptor binding the SET domain protein 1 gene, resulting in an alanine-to-glutamate substitution. The bioinformatics analysis suggested high pathogenicity at this site. This study provides insights into diagnosis of neonatal Sotos syndrome based on specific phenotypes. Subsequent treatment and follow-up should focus on developmental retardation, epilepsy, and scoliosis.


Assuntos
Síndrome de Sotos , Histona Metiltransferases/genética , Histona-Lisina N-Metiltransferase/genética , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Mutação , Mutação de Sentido Incorreto/genética , Proteínas Nucleares/química , Proteínas Nucleares/genética , Estudos Retrospectivos , Síndrome de Sotos/genética
6.
J Cardiovasc Magn Reson ; 23(1): 38, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33789701

RESUMO

BACKGROUND: Parameters of myocardial deformation may provide improved insights into right ventricular (RV) dysfunction. We quantified RV longitudinal myocardial function using a fast, semi-automated method and investigated its diagnostic and prognostic values in patients with repaired tetralogy of Fallot (rTOF) and pulmonary arterial hypertension (PAH), who respectively exemplify patients with RV volume and pressure overload conditions. METHODS: The study enrolled 150 patients (rTOF, n = 75; PAH, n = 75) and 75 healthy controls. RV parameters of interest were fast global longitudinal strain (GLS) and strain rates during systole (GLSRs), early diastole (GLSRe) and late diastole (GLSRa), obtained by tracking the distance from the medial and lateral tricuspid valve insertions to the RV epicardial apex on cine cardiovascular magnetic resonance (CMR). RESULTS: The RV fast GLS exhibited good agreement with strain values obtained by conventional feature tracking approach (bias - 4.9%, error limits (± 2·standard deviation) ± 4.3%) with fast GLS achieving greater reproducibility and requiring reduced analysis time. Mean RV fast GLS was reduced in PAH and rTOF groups compared to healthy controls (PAH < rTOF < healthy controls: 15.1 ± 4.9 < 19.3 ± 2.4 < 24.4 ± 3.0%, all P < 0.001 in pairwise comparisons). In rTOF patients, RV fast GLS was significantly associated with metabolic equivalents, peak oxygen consumption (PVO2) and percentage of predicted PVO2 achieved during cardiopulmonary exercise testing. Lower RV fast GLS was associated with subnormal exercise capacity in rTOF (area under the curve (AUC) = 0.822, sensitivity = 72%, specificity = 91%, cut-off = 19.3%). In PAH patients, reduced RV fast GLS was associated with RV decompensated hemodynamics (AUC = 0.717, sensitivity = 75%, specificity = 58%, cut-off = 14.6%) and higher risk of clinical worsening (AUC = 0.808, sensitivity = 79%, specificity = 70 %, cut-off = 16.0%). CONCLUSIONS: Quantitative RV fast strain and strain rate parameters assessed from CMR identify abnormalities of RV function in rTOF and PAH and are predictive of exercise capacity, RV decompensation and clinical risks in these patients. Trial registry Clinicaltrials.gov: NCT03217240.


Assuntos
Interpretação de Imagem Assistida por Computador , Imagem Cinética por Ressonância Magnética , Hipertensão Arterial Pulmonar/diagnóstico por imagem , Tetralogia de Fallot/diagnóstico por imagem , Disfunção Ventricular Direita/diagnóstico por imagem , Função Ventricular Direita , Pressão Ventricular , Adulto , Automação , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Hipertensão Arterial Pulmonar/complicações , Hipertensão Arterial Pulmonar/fisiopatologia , Reprodutibilidade dos Testes , Tetralogia de Fallot/fisiopatologia , Tetralogia de Fallot/cirurgia , Disfunção Ventricular Direita/etiologia , Disfunção Ventricular Direita/fisiopatologia , Adulto Jovem
7.
J Environ Manage ; 282: 111951, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33461088

RESUMO

Algal organic matter (AOM) and natural organic matter (NOM) from a typical eutrophic lake were comprehensively investigated in terms of their physico-chemical property, components and disinfection byproduct formation potentials (DBPFPs). The relationships between specific chemical properties of AOM and NOM with their corresponding DBPFPs were further evaluated during chlorination. Results indicated that AOM had lower specific UV absorbance (SUVA) but richer organic nitrogen contents than NOM. Fluorescence excitation emission matrix spectroscopy further demonstrated that AOM were chiefly composed of aromatic protein-like and soluble microbial byproduct-like matters, while NOM were mainly contributed from humic acid-like and soluble microbial byproduct-like substances. Although the molecular weight (MW) distribution of AOM and NOM showed no significant difference, size-exclusion chromatography with organic carbon as well as organic nitrogen detection (LC-OCD-OND) revealed that AOM were concentrated with the fraction of building blocks and NOM had higher concentrations of biopolymers and humics (HS). Moreover, AOM displayed higher DBPFPs than NOM, especially for nitrogenous DBPFP (N-DBPFP). MW < 1 kDa fractions both in AOM and NOM contributed the largest proportion to the formation of carbonaceous disinfection byproducts (C-DBPs). In addition, Pearson correlation analysis showed that bulk parameter SUVA was significantly relevant to the formation potentials of trihalomethane both in AOM and NOM, but was ineffective for carbonaceous DBPFP (C-DBPFP) prediction. Dissolved organic nitrogen contents in biopolymer and HS characterized by LC-OCD-OND had strong correlations with N-DBPFPs from AOM and NOM, indicating that LC-OCD-OND quantitative analysis could improve the prediction accuracy of the DBP formation than bulk parameters during NOM and AOM chlorination.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Desinfecção , Halogenação , Nitrogênio/análise , Trialometanos/análise , Poluentes Químicos da Água/análise
8.
BMC Med Genet ; 21(1): 51, 2020 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-32171285

RESUMO

INTRODUCTION: The AP4B1 gene encodes a subunit of adaptor protein complex-4 (AP4), a component of intracellular transportation of proteins which plays important roles in neurons. Bi-allelic mutations in AP4B1 cause autosomal recessive spastic paraplegia-47(SPG47). CASE PRESENTATION: Here we present a Chinese patient with spastic tetraplegia, moderate psychomotor development delay and febrile seizures plus. Brain MRIs showed dilated supratentorial ventricle, thin posterior and splenium part of corpus callosum. The patient had little progress through medical treatments and rehabilitating regimens. Whole exome sequencing identified novel compound heterozygous truncating variants c.1207C > T (p.Gln403*) and c.52_53delAC (p.Cys18Glnfs*7) in AP4B1 gene. Causal mutations in AP4B1 have been reported in 29 individuals from 22 families so far, most of which are homozygous mutations. CONCLUSIONS: Our study enriched the genetic and phenotypic spectrum of SPG47. Early discovery, diagnosis and proper treatment on the conditions generally increase chances of improvement on the quality of life for patients.


Assuntos
Complexo 4 de Proteínas Adaptadoras/genética , Subunidades beta do Complexo de Proteínas Adaptadoras/genética , Proteínas de Ligação a DNA/genética , Transtornos Psicomotores/genética , Quadriplegia/genética , Proteínas de Ligação a RNA/genética , Convulsões Febris/genética , Povo Asiático , Criança , China , Códon sem Sentido , Heterozigoto , Humanos , Masculino , Fenótipo , Subunidades Proteicas/genética , Transtornos Psicomotores/complicações , Quadriplegia/complicações , Convulsões Febris/complicações , Sequenciamento do Exoma
9.
Acta Pharmacol Sin ; 41(5): 730, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32081978

RESUMO

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

10.
Ecotoxicol Environ Saf ; 194: 110392, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32171965

RESUMO

The sensitivity of individual organisms towards toxic agents is an important indicator of environmental pollution. However, organism-specific quantification of sensitivity towards pollutants remains a challenge. In this study, we determined the sensitivity of Chlorella vulgaris (C. vulgaris) and Scenedesmus quadricauda (S. quadricauda) towards three ionic liquids (ILs), 1-alkyl-3-methyl-imidazolium chlorides [Cnmim][Cl] (n = 4,6,8). We kept all external parameters constant to identify the biotic parameters responsible for discrepancies in species sensitivity, and used flow cytometry to determine four conventional endpoints to characterise cell viability and cell vitality. Our results demonstrate that after exposure to the ILs, cell proliferation was inhibited in both species. At the same time, the cell size, complexity and membrane permeability of both algae also increased. However, while Chl a synthesis by S. quadricauda was inhibited, that of C. vulgaris was enhanced. S. quadricauda has evolved a metabolic defense that can counteract the decreased esterase activity that has been shown to occur in the presence of ILs. While it is likely that S. quadricauda was less sensitive than C. vulgaris to the ILs because of this metabolic defense, this alga may also exhibit better membrane resistance towards ILs.


Assuntos
Chlorella vulgaris/efeitos dos fármacos , Líquidos Iônicos/toxicidade , Scenedesmus/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Sobrevivência Celular/efeitos dos fármacos , Chlorella vulgaris/citologia , Chlorella vulgaris/metabolismo , Citometria de Fluxo , Scenedesmus/citologia , Scenedesmus/metabolismo , Especificidade da Espécie
11.
Analyst ; 144(6): 1916-1922, 2019 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-30681671

RESUMO

Antibiotics have been noted as an important class of emerging contaminants in the environment. Metal-organic frameworks (MOFs), which have been intensely investigated as a novel kind of sensing material, have been tentatively applied to the detection of antibiotics in recent years. In this work, a nanoscale MOF (In-sbdc) with a strong (quantum yield = 13%) and stable emission in water was synthesized. With its effective spectral overlap with tetracyclines, adsorption preconcentration and the usage of a masking agent, In-sbdc gave sensitive responses to a series of tetracycline antibiotics (tetracycline, chlorotetracycline and oxytetracycline) with detection limits of 0.28-0.30 µM, but another eight tested kinds of antibiotics did not cause a remarkable change in its emission (<10% of the response caused by an equal amount of tetracyclines). This MOF-based sensing system was successfully applied to tetracyclines detection in a series of actual water and food samples.


Assuntos
Antibacterianos/análise , Técnicas Biossensoriais , Monitoramento Ambiental/métodos , Análise de Alimentos/métodos , Estruturas Metalorgânicas/química , Tetraciclinas/análise , Poluentes Químicos da Água/análise , Fluorescência , Limite de Detecção
12.
Cell Physiol Biochem ; 45(6): 2506-2515, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29554650

RESUMO

BACKGROUND/AIMS: Low back pain has become one of the most common musculoskeletal diseases in the world. Studies have shown that intervertebral disc degeneration (IDD) is an important factor leading to low back pain, but the mechanisms underlying IDD remain largely unknown. Research over the past decade has suggested critical roles for microRNAs (miRNAs) in natural growth and disease progression. However, it remains poorly understood whether circular RNAs participate in IDD. METHODS: Clinical IDD samples were collected from 20 patients who underwent discectomy. Weighted gene co-expression network analysis was used to identify the co-expression miRNA network modules (highly co-expressed clusters of miRNAs) that were associated with IDD grade. RESULTS: miR-3150a-3p was the most significantly up-regulated miRNA in module "Blue." Notably, aggrecan (ACAN) was identified as a direct target gene of miR-3150a-3p and ACAN expression was regulated by miR-3150a-3p. Overexpression of miR-3150a-3p decreased ACAN expression in nucleus pulposus cells, whereas inhibition of miR-3150a-3p increased ACAN expression. In addition, ACAN expression was negatively correlated with IDD grade. CONCLUSION: Our study suggests that the reduction of ACAN expression induced by the upregulation of miR-3150a-3p might participate in the development of IDD.


Assuntos
Agrecanas/genética , Degeneração do Disco Intervertebral/genética , MicroRNAs/metabolismo , Adulto , Regulação para Baixo , Feminino , Humanos , Degeneração do Disco Intervertebral/patologia , Masculino , MicroRNAs/genética , Pessoa de Meia-Idade , Núcleo Pulposo/metabolismo , Núcleo Pulposo/patologia , Regulação para Cima
13.
J Clin Rheumatol ; 24(1): 18-24, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29200018

RESUMO

OBJECTIVES: Interleukin 23 (IL-23) pathway and IL-1 cluster genes play prominent role in the etiopathology of ankylosing spondylitis (AS). The aim of this study was to investigate the diagnostic and prognostic role of 5 single-nucleotide polymorphisms related to IL-23 pathway and IL-1 cluster genes in AS patients. METHODS: Four hundred thirty-one patients with AS and 206 age- and sex-matched healthy controls were recruited in this prospective cohort study. Five potential single-nucleotide polymorphisms (IL-23R [rs11209026], IL-12B [rs6871626], TYK2 [rs6511701], IL-6R [rs4129267], and IL-1R2 [rs2192752]) related to IL-23 pathway and IL-1 cluster genes by analyzing previous studies were genotyped. Among 431 total AS patients, 198 active cases were treated and followed up for 24 weeks. RESULTS: Frequencies of IL-12B AA (rs6871626) and IL-6R TT (rs4129267) genotypes were increased in AS patients compared with healthy controls (both P < 0.001), and IL-12B A (rs6871626) as well as IL-6R T (rs4129267) allele increased the risk of AS independently (both P < 0.001). The Bath Ankylosing Spondylitis Disease Activity Index score was found to be elevated in AS patients with IL-12B AA (rs6871626) compared with patients with the CA and CC genotypes (P = 0.002 and P < 0.001, respectively), and the Bath Ankylosing Spondylitis Functional Index score was also increased in AS patents with IL-12B AA (rs6871626) than in those with the CA and CC genotypes (P = 0.001 and P < 0.001). In addition, IL-6R T (rs4129267) allele could predict a worse ASAS-20 (Assessment of SpondyloArthritis international Society) response at week 24 as an independent factor by multivariate logistic regression analysis with additive model (P = 0.011). CONCLUSIONS: Interleukin 12B (rs6871626) and IL-6R (rs4129267) gene polymorphisms could serve as promising biomarkers for diagnosis and prognosis in AS patients.


Assuntos
Subunidade p40 da Interleucina-12/genética , Receptores de Interleucina-6/genética , Espondilite Anquilosante , Adulto , China/epidemiologia , Estudos de Coortes , Feminino , Marcadores Genéticos , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Prognóstico , Estudos Prospectivos , Espondilite Anquilosante/diagnóstico , Espondilite Anquilosante/epidemiologia , Espondilite Anquilosante/genética , Espondilite Anquilosante/imunologia
14.
Chemistry ; 23(27): 6562-6569, 2017 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-28133823

RESUMO

Metal-organic frameworks (MOFs) are emerging in recent years as a kind of versatile fluorescent sensing materials, but their application to enzyme assays has rarely been studied. Here, the first example of a MOF-based label-free enzyme assay system is reported. A luminescent MOF was synthesized and applied to the activity analysis of polyphenol oxidase (PPO). With its distinct responses to the phenolic substrate and o-quinone product, this MOF could transduce the extent of PPO-catalyzed oxidation to fluorescence signal and enable the real-time monitoring of this reaction. Wide substrate adaptability and high sensitivity (detection limit=0.00012 U mL-1 ) were exhibited by this method, which meets the requirement of common bioanalysis. Interestingly, by the comparison with molecular capturing reagents, the heterogeneous nature of this MOF-based assay effectively preventing the interaction with the enzyme was proven, thus ensuring the authenticity of results.


Assuntos
Catecol Oxidase/metabolismo , Estruturas Metalorgânicas/química , Agaricales/enzimologia , Biocatálise , Ensaios Enzimáticos , Ligantes , Limite de Detecção , Oxirredução , Quinonas/química , Quinonas/metabolismo , Solanum tuberosum/enzimologia , Espectrometria de Fluorescência , Especificidade por Substrato
15.
Chemistry ; 23(61): 15498-15504, 2017 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-28836296

RESUMO

As novel fluorescent-sensing materials, metal-organic frameworks (MOFs) have shown great potential in environmental monitoring. However, most of the researches are limited to traditional pollutants, whereas the application of MOFs to the detection of the pollutants with more complicated structures, such as endocrine disrupting chemicals (EDCs), has rarely been explored. The difficulties faced in the sensing of EDCs include their electronic stability and the structural similarity among homologues, which could be overcome by the incorporation of enzymatic reaction. In this work, the first example of enzyme-assisted MOF-fluorescent-sensing was developed for the analysis of diethylstilbestrol (DES, a synthetic estrogen). In this system, DES is first oxidized by HRP/H2 O2 quantitatively to its quinone form, and then the quinone product is selectively captured by a stilbene based luminescent MOF to induce fluorescence response. By the tandem sensitization and filtration of enzymatic reaction and MOF adsorption, this method shows high sensitivity (DL=89 nm) and can distinguish DES from other similar-structured EDCs.

16.
Acta Pharmacol Sin ; 38(1): 29-40, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27840407

RESUMO

Recent studies focus on promoting neurite outgrowth to remodel the central nervous network after brain injury. Currently, however, there are few drugs treating brain diseases in the clinic by enhancing neurite outgrowth. In this study, we established an NGF-induced PC12 differentiation model to screen novel compounds that have the potential to induce neuronal differentiation, and further characterized 4,10-Aromadendranediol (ARDD) isolated from the dried twigs of the Baccharis gaudichaudiana plant, which exhibited the capability of promoting neurite outgrowth in neuronal cells in vitro. ARDD (1, 10 µmol/L) significantly enhanced neurite outgrowth in NGF-treated PC12 cells and N1E115 cells in a time-dependent manner. In cultured primary cortical neurons, ARDD (5, 10 µmol/L) not only significantly increased neurite outgrowth but also increased the number of neurites on the soma and the number of bifurcations. Further analyses showed that ARDD (10 µmol/L) significantly increased the phosphorylation of ERK1/2 and the downstream GSK-3ß, subsequently induced ß-catenin expression and up-regulated the gene expression of the Wnt ligands Fzd1 and Wnt3a in neuronal cells. The neurite outgrowth-promoting effect of ARDD in neuronal cells was abolished by pretreatment with the specific ERK1/2 inhibitor PD98059, but was partially reversed by XAV939, an inhibitor of the Wnt/ß-catenin pathway. ARDD also increased the expression of BDNF, CREB and GAP-43 in N1E115 cells, which was reversed by pretreatment with PD98059. In N1E115 cells subjected to oxygen and glucose deprivation (OGD), pretreatment with ARDD (1-10 µmol/L) significantly enhanced the phosphorylation of ERK1/2 and induced neurite outgrowth. These results demonstrated that the natural product ARDD exhibits neurite outgrowth-inducing activity in neurons via activation of the ERK signaling pathway, which may be beneficial to the treatment of brain diseases.


Assuntos
Proteína GAP-43/biossíntese , Proteína GAP-43/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Neuritos/efeitos dos fármacos , Sesquiterpenos/farmacologia , Animais , Fator Neurotrófico Derivado do Encéfalo/biossíntese , Células Cultivadas , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/biossíntese , Flavonoides/farmacologia , Compostos Heterocíclicos com 3 Anéis/farmacologia , Camundongos , Fator de Crescimento Neural/farmacologia , Neuritos/metabolismo , Neuritos/ultraestrutura , Fosforilação/efeitos dos fármacos , Cultura Primária de Células , Ratos , Sesquiterpenos/antagonistas & inibidores , Sesquiterpenos de Guaiano
17.
Luminescence ; 32(6): 908-912, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28071869

RESUMO

CaSnO3 :Bi3+ blue-emitting phosphor was synthesized using a high-temperature solid-state reaction method in air. The crystal structures and luminescence properties were investigated. A broad emission band peaking at ~448 nm upon excitation at 262 and 308 nm was observed in the range 330-680 nm at room temperature due to 3 P1  â†’ 1 S0 transition of the Bi3+ ion. The chromaticity coordinate was (0.1786, 0.1665). The optimal Bi3+ ion concentration was ~0.6 mol% in CaSnO3 :Bi3+ phosphor. The emission spectrum of CaSnO3 :Bi3+ phosphor showed a blue-shift with increasing temperature from 50 to 300 K due to the influence of temperature on the electron transition of the Bi3+ ion. The emission intensity of CaSnO3 :Bi3+ phosphor may be increased ~1.45 times by co-doping Li+ ions as a charge compensator and fluxing agent. The luminescence mechanism is explained by a configurational coordinate diagram of Bi3+ ion in CaSnO3 :Bi3+ phosphor.


Assuntos
Bismuto/química , Lítio/química , Substâncias Luminescentes/síntese química , Cor , Luminescência , Substâncias Luminescentes/química , Medições Luminescentes
18.
Reproduction ; 149(2): 163-70, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25385720

RESUMO

Tri-ortho-cresyl phosphate (TOCP) has been widely used as plasticizers, plastic softeners, and flame retardants in industry and reported to have a deleterious effect on the male reproductive system in animals besides delayed neurotoxicity. Our preliminary results found that TOCP could disrupt the seminiferous epithelium in the testis and inhibit spermatogenesis, but the precise mechanism is yet to be elucidated. This study shows that TOCP inhibited viability of rat spermatogonial stem cells in a dose-dependent manner. TOCP could not lead to cell cycle arrest in the cells; the mRNA levels of p21, p27, p53, and cyclin D1 in the cells were also not affected by TOCP. Meanwhile, TOCP did not induce apoptosis of rat spermatogonial stem cells. After treatment with TOCP, however, both LC3-II and the ratio of LC3-II/LC3-I were markedly increased; autophagy proteins ATG5 and beclin 1 were also increased after treatment with TOCP, indicating that TOCP could induce autophagy in the cells. Ultrastructural observation under the transmission electron microscopy indicated that autophagic vesicles in the cytoplasm containing extensively degraded organelles such as mitochondria and endoplasmic reticulum increased significantly after the cells were treated with TOCP. In summary, we have shown that TOCP can inhibit viability of rat spermatogonial stem cells and induce autophagy of the cells, without affecting cell cycle and apoptosis.


Assuntos
Autofagia/efeitos dos fármacos , Espermatogônias/efeitos dos fármacos , Células-Tronco/efeitos dos fármacos , Tritolil Fosfatos/farmacologia , Animais , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/análise , Proteína 5 Relacionada à Autofagia , Proteína Beclina-1 , Ciclo Celular/efeitos dos fármacos , Células Cultivadas , Masculino , Microscopia Eletrônica de Transmissão , Proteínas/análise , Ratos , Espermatogônias/química , Espermatogônias/ultraestrutura , Células-Tronco/química , Células-Tronco/ultraestrutura
19.
Phys Rev Lett ; 114(24): 245502, 2015 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-26196985

RESUMO

The observation of phonons in graphene by inelastic electron tunneling spectroscopy has been met with limited success in previous measurements arising from weak signals and other spectral features which inhibit a clear distinction between phonons and miscellaneous excitations. Utilizing a back-gated graphene device that allows adjusting the global charge carrier density, we introduce an averaging method where individual tunneling spectra at varying charge carrier density are combined into one representative spectrum. This method improves the signal for inelastic transitions while it suppresses dispersive spectral features. We thereby map the total graphene phonon density of states, in good agreement with density functional calculations. Unexpectedly, an abrupt change in the phonon intensity is observed when the graphene charge carrier type is switched through a variation of the back-gate electrode potential. This sudden variation in phonon intensity is asymmetric in the carrier type, depending on the sign of the tunneling bias.

20.
Bioorg Med Chem Lett ; 25(17): 3592-6, 2015 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-26152428

RESUMO

Au, Se and porphyrin are widely used components in the design of anticancer drugs, but their combination has never been referred to. In this work, a Se-modified porphyrin Au(III) complex, [AuTPP-Se]Cl, was designed and synthesized as a potential anticancer agent. This compound exhibits remarkable antiproliferative activity on all the six tested cancer cells. Its potency on HepG2 is even ten times higher than that of CDDP. The synergistic action among Au, Se and porphyrin components was validated. Mechanism study showed that both the induction of mitochondria-dependent apoptosis and the arrest of cell cycle contribute to the anticancer activity of [AuTPP-Se]Cl.


Assuntos
Antineoplásicos/química , Compostos Organoáuricos/química , Porfirinas/química , Compostos de Selênio/química , Antineoplásicos/farmacologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/patologia , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Compostos Organoáuricos/farmacologia , Porfirinas/farmacologia , Compostos de Selênio/farmacologia
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