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1.
Molecules ; 29(13)2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38999010

RESUMEN

Hypochlorite (ClO-) and viscosity both affect the physiological state of mitochondria, and their abnormal levels are closely related to many common diseases. Therefore, it is vitally important to develop mitochondria-targeting fluorescent probes for the dual sensing of ClO- and viscosity. Herein, we have explored a new fluorescent probe, XTAP-Bn, which responds sensitively to ClO- and viscosity with off-on fluorescence changes at 558 and 765 nm, respectively. Because the emission wavelength gap is more than 200 nm, XTAP-Bn can effectively eliminate the signal crosstalk during the simultaneous detection of ClO- and viscosity. In addition, XTAP-Bn has several advantages, including high selectivity, rapid response, good water solubility, low cytotoxicity, and excellent mitochondrial-targeting ability. More importantly, probe XTAP-Bn is successfully employed to monitor the dynamic change in ClO- and viscosity levels in the mitochondria of living cells and zebrafish. This study not only provides a reliable tool for identifying mitochondrial dysfunction but also offers a potential approach for the early diagnosis of mitochondrial-related diseases.


Asunto(s)
Colorantes Fluorescentes , Ácido Hipocloroso , Mitocondrias , Pez Cebra , Ácido Hipocloroso/análisis , Colorantes Fluorescentes/química , Animales , Mitocondrias/metabolismo , Viscosidad , Humanos , Imagen Óptica/métodos , Células HeLa
2.
Molecules ; 29(15)2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39125064

RESUMEN

In the human body, carboxylesterases (CEs) play crucial roles in xenobiotic metabolism and lipid homeostasis. But abnormal expression of CEs is highly associated with some diseases, such as hyperlipidemia, diabetes, and liver cancer. Therefore, it is of great importance to develop an efficient tool for the accurate detection of CEs in living organisms. Herein, an innovative near-infrared (NIR) fluorescent probe, TTAP-AB, was designed for CE detection based on the aggregation-induced emission (AIE) mechanism. This probe exhibits rapid response (2 min), excellent sensitivity (limit of detection = 8.14 × 10-6 U/mL), and high selectivity to CEs. Additionally, owing to its good biocompatibility, the TTAP-AB probe enables the monitoring of dynamic changes in CE levels under drug-induced modulation in living cells and zebrafish. More importantly, the TTAP-AB probe was successfully employed to image liver tumors and assist in tumor resection through the real-time monitoring of CEs, indicating that TTAP-AB is promising to guide liver cancer surgery. Therefore, the TTAP-AB probe can not only enrich the strategies for CE detection in biological systems but also has great potential for some clinical imaging applications, including medical diagnosis, preclinical research, and imaging-guided surgery.


Asunto(s)
Hidrolasas de Éster Carboxílico , Colorantes Fluorescentes , Pez Cebra , Animales , Colorantes Fluorescentes/química , Ratones , Humanos , Hidrolasas de Éster Carboxílico/metabolismo , Imagen Óptica/métodos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/diagnóstico por imagen , Línea Celular Tumoral
3.
Analyst ; 147(22): 5011-5017, 2022 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-36278793

RESUMEN

Graphene nanosheets (GS) were prepared by ultrasonic exfoliation of bulk graphite in N-methyl-2-pyrrolidone with the assistance of sodium pyrophosphate. The obtained GS suspension was modified on a glassy carbon electrode (GS/GCE), and then functionalized at different voltages (e.g. 1.0, 1.4 and 1.6 V) for 2 min in pH 7.0 phosphate buffer. The electrochemically functionalized GS/GCE (i.e. EGS/GCE) possesses more oxygen-containing groups and a higher defect level. More importantly, the active response area, electron transfer ability and interface adsorption capacity of the EGS/GCE enhanced remarkably. The possible mechanism of the performance enhancement is discussed, and the sensing application of the EGS/GCE in the detection of nitrofurazone (NFZ) is investigated. Compared with the GS/GCE, the EGS/GCE is much more active for NFZ oxidation and greatly increases the detection sensitivity. As a result, a highly sensitive electrochemical detection method has been developed for NFZ, with a detection limit of 2.1 nM. The practical application of the EGS/GCE was tested in fish meat samples, showing good accuracy and feasibility.


Asunto(s)
Grafito , Animales , Nitrofurazona , Técnicas Electroquímicas/métodos , Electrodos , Oxidación-Reducción , Carbono
4.
Pestic Biochem Physiol ; 188: 105287, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36464340

RESUMEN

The application of fungicide mixture is one of the most important measures to extend the service life of highly selective fungicides. Pyraclostrobin (PYR), which has been extensively used to control plant diseases by inhibiting mitochondrial respiration of pathogenic fungi, is at a high risk of resistance development. In this study, the potential of PYR alone or in combination with cystamine, an inhibitor of microbial transglutaminase, to suppress Fusarium graminearum was tested in vitro and in vivo. A synergistic effect of PYR/CYS mixture was observed both in vitro and when applied to etiolated wheat coleoptile. The control effect of PYR/CYS mixture on F. graminearum was better than that of PYR alone, which was reflected by the increased protection effect. The discrepancies of membrane permeability and the redox-physiological state were observed between PYR and PYR/CYS treatments, suggesting that an increased PYR availability in F. graminearum mycelia could be related with the observed synergistic action. Moreover, a synergistic profile was observed between PYR and CYS in regard of massive autophagosomes in mycelia, indicating that enhanced autophagy could be involved in the mode of action of PYR/CYS mixture. The differential content of mitochondrial metabolites between PYR and PYR/CYS treatments also provided evidence for CYS contribution to the fungicidal action of PYR/CYS mixture. The results provide insight into the synergistic mechanism of action of PYR/CYS mixture and an effective way to enhance the efficiency of PYR to combat F. graminearum.


Asunto(s)
Cistamina , Fungicidas Industriales , Autofagia , Fungicidas Industriales/farmacología , Permeabilidad
5.
Entropy (Basel) ; 23(9)2021 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-34573797

RESUMEN

Combined with the B-P (breakpoint) test and VAR-DCC-GARCH model, the relationship between WTI crude oil futures and S&P 500 index futures or CSI 300 index futures was investigated and compared. The results show that breakpoints exist in the relationship in the mean between WTI crude oil futures market and Chinese stock index futures market or US stock index futures market. The relationship in mean between WTI crude oil futures prices and S&P 500 stock index futures, or CSI 300 stock index futures is weakening. Meanwhile, there is a decreasing dynamic conditional correlation between the WTI crude oil futures market and Chinese stock index futures market or US stock index futures market after the breakpoint in the price series. The Chinese stock index futures are less affected by short-term fluctuations in crude oil futures returns than US stock index futures.

6.
Mikrochim Acta ; 187(2): 142, 2020 01 21.
Artículo en Inglés | MEDLINE | ID: mdl-31965326

RESUMEN

A sol-gel method is presented to synthesize molecularly imprinted polymers (MIPs) composed with a copper-based metal-organic framework (referred to as MIP/HKUST-1) on a paper support to selectively recognize tetrabromobisphenol A (TBBPA). The imprinting factor is 7.6 and the maximum adsorption capacity is 187.3 mg g-1. This is much better than data for other MIPs. The degradation of TBBPA is introduced in the procedure. Due to the selective recognition by the MIP, the enzyme-mimicking properties of HKUST-1 under the MIP layer became weak due to the decrease of residue imprinted cavities. And adsorbed TBBPA can be degraded under consumption of hydrogen peroxide (H2O2). The combined effect of H2O2 and HKUST-1 cause the coloration caused by catalytic oxidation of 3,3',5,5'-tetramethylbenzidine to become less distinct. This amplification strategy is used for the ultrasensitive and highly selective colorimetric determination of TBBPA. The gray intensity is proportional to the logarithm concentration of TBBPA in the range of 0.01-10 ng g-1. The limit of detection is as low as 3 pg g-1, and the blank intensities caused by TBBPA analogues are <1% of that caused by TBBPA at the same concentration, this implying excellent selectivity. The spiked recoveries ranged from 94.4 to 106.6% with relative standard deviation values that were no more than 8.6%. Other features include low costs, rapid response, easy operation and on-site testing. Graphical abstractSchematic representation of colorimetric determination of tetrabromobisphenol A (TBBPA) by paper-based metal-organic framework-based molecularly imprinted polymers (MIP/HKUST-1 composites) using 3,3',5,5'-tetramethylbenzidine (TMB) as a substrate.


Asunto(s)
Colorimetría/métodos , Estructuras Metalorgánicas/química , Impresión Molecular , Imitación Molecular , Bifenilos Polibrominados/análisis , Polímeros/química , Adsorción , Bencidinas/metabolismo , Enzimas , Peróxido de Hidrógeno/química , Límite de Detección
7.
J Sep Sci ; 41(22): 4096-4104, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30230241

RESUMEN

A simple, cost-effective, sensitive, and quick method for the determination of nitenpyram and its metabolite 6-chloronicotinic acid in environmental samples was developed by coupling an ion chromatograph with a fluorescence detector and a post-column photochemical reactor. This developed analytical method involved a rapid sample extraction by modified and miniaturized quick, easy, cheap, effective, rugged, and safe method followed by isocratic ion chromatographic separation of nitenpyram and 6-chloronicotinic acid into an IonPac™ AS11-HC column protected by IonPac™ AG11A guard column by running 30 mM NaOH + 10% acetonitrile mobile phase. A homemade post-column photochemical reactor was also integrated with the ion chromatographic system for online transformation of both analytes into their respective highly fluorescent photoproduct in basic media without using an extra pump. The developed method was validated by following SANTE/11945/2015 guidelines on analytical quality control and validation procedures. The method showed a good linear response (r > 0.999), improved limit of detection (0.101-0.132 µg/L), minimum or no matrix effect, excellent recoveries (90.2-100.10%) and relative standard deviations were found to be ≤6.50%.


Asunto(s)
Contaminantes Ambientales/química , Neonicotinoides/análisis , Ácidos Nicotínicos/análisis , Cromatografía por Intercambio Iónico , Monitoreo del Ambiente , Estructura Molecular , Procesos Fotoquímicos , Espectrometría de Fluorescencia
8.
J Cell Mol Med ; 18(7): 1334-43, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24758696

RESUMEN

Beta-adrenoceptor (ß-AR) exerts critical regulation of cardiac function. MicroRNAs (miRNAs) are potentially involved in a variety of biological and pathological processes. This study aimed to investigate the role of miRNA let-7e in the up-regulation of ß(1) -AR and arrhythmogenesis in acute myocardial infarction (AMI) in rats. ß(1) -AR expression was significantly up-regulated and let-7a, c, d, e and i were markedly down-regulated in the infarcted heart after 6 and 24 hrs myocardial infarction. Forced expression of let-7e suppressed ß(1) -AR expression at the protein level, without affecting ß(1) -AR mRNA level, in neonatal rat ventricular cells (NRVCs). Silencing of let-7e by let-7e antisense inhibitor (AMO-let-7e) enhanced ß(1) -AR expression at the protein level in NRVCs. Administration of the lentivirus vector containing precursor let-7e (len-pre-let-7e) significantly inhibited ß(1) -AR expression in rats, whereas len-AMO-let-7e up-regulated ß(1) -AR relative to the baseline control level, presumably as a result of depression of tonic inhibition of ß(1) -AR by endogenous let-7e. Len-negative control (len-NC) did not produce significant influence on ß(1) -AR expression. Len-pre-let-7e also profoundly reduced the up-regulation of ß(1) -AR induced by AMI and this effect was abolished by len-AMO-let-7e. Importantly, len-pre-let-7e application significantly reduced arrhythmia incidence after AMI in rats and its anti-arrhythmic effect was cancelled by len-AMO-let-7e. Notably, anti-arrhythmic efficacy of len-pre-let-7e was similar to propranolol, a non-selective ß-AR blocker and metoprolol, a selective ß(1) -AR blocker. Down-regulation of let-7e contributes to the adverse increase in ß(1) -AR expression in AMI and let-7e supplement may be a new therapeutic approach for preventing adverse ß(1) -AR up-regulation and treating AMI-induced arrhythmia.


Asunto(s)
Antiarrítmicos , Arritmias Cardíacas/prevención & control , MicroARNs/genética , Infarto del Miocardio/prevención & control , Miocitos Cardíacos/metabolismo , Receptores Adrenérgicos beta 1/química , Regiones no Traducidas 3'/genética , Animales , Arritmias Cardíacas/genética , Arritmias Cardíacas/patología , Biomarcadores/análisis , Western Blotting , Células Cultivadas , Perfilación de la Expresión Génica , Regulación de la Expresión Génica , Frecuencia Cardíaca , Masculino , Infarto del Miocardio/genética , Infarto del Miocardio/patología , Miocitos Cardíacos/patología , ARN Mensajero/genética , Ratas , Ratas Wistar , Reacción en Cadena en Tiempo Real de la Polimerasa , Receptores Adrenérgicos beta 1/genética , Receptores Adrenérgicos beta 1/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
9.
Pharmaceutics ; 16(1)2024 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-38276519

RESUMEN

The unique properties of ionic liquids (ILs), such as structural tunability, good solubility, chemical/thermal stability, favorable biocompatibility, and simplicity of preparation, have led to a wide range of applications in the pharmaceutical and biomedical fields. ILs can not only speed up the chemical reaction process, improve the yield, and reduce environmental pollution but also improve many problems in the field of medicine, such as the poor drug solubility, product crystal instability, poor biological activity, and low drug delivery efficiency. This paper presents a systematic and concise analysis of the recent advancements and further applications of ILs in the pharmaceutical field from the aspects of drug synthesis, drug analysis, drug solubilization, and drug crystal engineering. Additionally, it explores the biomedical field, covering aspects such as drug carriers, stabilization of proteins, antimicrobials, and bioactive ionic liquids.

10.
Cell Physiol Biochem ; 32(6): 1818-29, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24356076

RESUMEN

BACKGROUND: Arsenic trioxide (As2O3), an ancient drug used in traditional Chinese medicine, has substantial anticancer activities, especially in the treatment of patients suffering from acute promyelocytic leukemia (APL); however the underlying mechanisms are not well understood. METHODS: MTT assay was used to detect the cell viability. Flow Cytometry analysis and caspase-3 activity assay were used to measure apoptosis of APL cells. Caspase-3 and Bax levels were analyzed by western blot and let-7d and miR-766 levels were determined by real-time RT-PCR. RESULTS: As2O3 significantly inhibited cell viability and induced apoptosis in APL cells. Several microRNAs, including let-7d and miR-766, were dysregulated in APL cells treated with As2O3. The expression of caspase-3 and Bax, which are targets of let-7d and miR-766, respectively, were up-regulated in As2O3 treated cells. Transfection of let-7d and miR-766 into NB4 cells decreased the expression of caspase-3 and Bax, respectively. Correspondingly, transfection of these microRNAs increased NB4 cell viability. As2O3 induced degradation of promyelocytic leukemia (PML), and then induced the down-regulation of both let-7d and miR-766 in NB4 cells. CONCLUSIONS: We construct a dysregulated microRNA network involved in As2O3-induced apoptosis in APL. Targeting this network may be a new strategy for the prevention of side effects associated with APL treatment with As2O3.


Asunto(s)
Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Arsenicales/farmacología , MicroARNs/metabolismo , Óxidos/farmacología , Regiones no Traducidas 3' , Trióxido de Arsénico , Secuencia de Bases , Caspasa 3/genética , Caspasa 3/metabolismo , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Fragmentación del ADN/efectos de los fármacos , Regulación hacia Abajo/efectos de los fármacos , Células HL-60 , Humanos , Leucemia Promielocítica Aguda/metabolismo , Leucemia Promielocítica Aguda/patología , ARN Mensajero/química , ARN Mensajero/metabolismo , Alineación de Secuencia , Regulación hacia Arriba/efectos de los fármacos , Proteína X Asociada a bcl-2/genética , Proteína X Asociada a bcl-2/metabolismo
11.
J AOAC Int ; 96(1): 1-6, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23513948

RESUMEN

The systemicity of chlorantraniliprole was investigated and evidence was collected for formulating strategies in controlling vegetable or rice pests. Systemicity of chlorantraniliprole was investigated through chlorantraniliprole application on velvetleaf (Abutilon theophrasti) leaves as well as through hydroponic experiments. The roots of velvetleaf were incubated in chlorantraniliprole solution with a concentration of 50 microg/mL; the concentrations of chlorantraniliprole in xylem above the solution parts were 3.14, 5.67, and 6.89 microg/g at 24, 48, and 72 h after treatment. When the roots were incubated in chlorantraniliprole solution with a concentration of 200 microg/mL, the concentrations of chlorantraniliprole in xylem above the solution reached 6.48, 8.76, and 10.55 microg/g at 24, 48, and 72 h after treatment. Chlorantraniliprole was not detected in the phloem above the solution after these two treatments. When chlorantraniliprole solution with a concentration of 100 microg/mL was applied on mature leaves, chlorantraniliprole was found in xylem above the mature leaves at concentrations of 0.55, 0.74, and 0.92 microg/g at 24, 48, and 72 h after the treatment. No chlorantraniliprole was detected in the leaves below the mature leaves or the phloem above them. When chlorantraniliprole solution with a concentration of 100 microg/mL was applied on apical leaves, no chlorantraniliprole was detected in the xylem or phloem below them. These results indicated that chlorantraniliprole can be transported through xylem only upward, but chlorantraniliprole has no phloem mobility in velvetleaf.


Asunto(s)
Insecticidas/análisis , Malvaceae/química , ortoaminobenzoatos/análisis , Cromatografía Líquida de Alta Presión , Floema/química , Espectrometría de Masas en Tándem , Xilema/química
12.
Chemosphere ; 319: 137995, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36731669

RESUMEN

Volatile organic compound (VOC) removal by photocatalytic oxidation (PCO) is the practical and economical process to reduce air pollutants. Many conditions, such as temperature, initial concentration of VOC, relative humidity, gas flow rate, and light intensity, affected this process. Therefore, finding the optimal operating conditions for the PCO process can increase the efficiency of the process and also operate the process more economically. Also, it is possible to scale up the process with more confidence by the kinetics modeling of the process and finding the rate constants. In this study, the effect of gas flow rate, light intensity, and VOC inlet concentration were investigated. The results show that the flow rate of 15 lit/min is more efficient, and the effect of the pollutant input concentration and light intensity directly affects the conversion percentage. The kinetic study of acetaldehyde removal was investigated in the fluidized bed reactor, and the best kinetic model was proposed based on reactor model regression on the outlet concentration data. The best model describes a langmuir-hynshelwood type model with adsorbed acetaldehyde's inhibition effect on the catalyst's surface. The R2 coefficient for the best kinetic type is 0.98.


Asunto(s)
Contaminantes Atmosféricos , Compuestos Orgánicos Volátiles , Catálisis , Oxidación-Reducción , Óxidos
13.
Bull Environ Contam Toxicol ; 89(5): 1021-6, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22983724

RESUMEN

Flubendiamide, which belongs to the new chemical class of phthalic acid diamides, is widely used against lepidopteron pests in a variety of vegetable and rice pests. It provides superior plant protection against a broad range of economically important lepidopterous pests, including Spodoptera exigua and Plutella xylostella. A determination method of flubendiamide in the cabbage was established in this paper. Flubendiamide in the cabbage was extracted with acetonitrile and ultrasonic extraction, and was purified by QuEChERS and analyzed by LC-MS/MS (liquid chromatography-tandem mass spectrometry). The results indicated that the average recovery of flubendiamide in the cabbage was 81.27%-91.45%, the coefficient of variation was 1.79%-4.81%, and the lowest detection concentration was 0.3 µg/kg. The extraction of flubendiamide from the cabbage and its analysis was in accordance with the pesticide residue criterion, i.e., simple, rapid, accurate, reproducible, stable, separatory, and convenient. It identifies and quantifies trace-level flubendiamide residues in the cabbage extracts using LC-MS/MS in the ESI negative mode coupled with the QuEChERS method.


Asunto(s)
Benzamidas/análisis , Brassica/química , Contaminación de Alimentos/análisis , Insecticidas/análisis , Residuos de Plaguicidas/análisis , Sulfonas/análisis , Cromatografía Liquida , Espectrometría de Masas en Tándem
14.
J Chromatogr A ; 1682: 463505, 2022 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-36152484

RESUMEN

A novel nano petal-shaped covalent organic frameworks modified magnetic polystyrene-divinylbenzene-glycidylmethacrylate (NP-COF@Mag-PS/DVB/GMA) microsphere has been synthesized. It is a perfect combination of high productivity of PS/DVB/GMA microspheres and excellent enrichment efficiency of COF particles, and the excellent properties of NP-COF@Mag-PS/DVB/GMA microspheres are characterized by scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET) and X-ray photoelectron spectroscopy (XPS). The sorbent can extract illicit drugs via the reverse-phase interactions provided by benzene ring on the polymer backbone and the hydrogen bonding interactions provided by functional group (-NH-) on the COF particles. Based on using NP-COF@Mag-PS/DVB/GMA as sorbents, an easiness-to-handle of magnetic dispersive solid phase extraction (Mag-dSPE) procedure is proposed for the simultaneous preconcentration of 12 illicit drugs from wastewater. The obtained results show high extraction efficiency of NP-COF@Mag-PS/DVB/GMA to illicit drugs with recoveries between 81.6 and 116%. Furthermore, a liquid chromatography-tandem quadrupole mass spectrometry (LC-MS/MS) method for the determination of 12 illicit drugs from wastewater at sub-ppt levels has been proposed and validated with the pretreatment of samples by Mag-dSPE. The limits of quantification (LOQs) for the 12 illicit drugs are between 0.40 and 4.90 ng/L. Validation results on linearity, specificity, trueness and precision, as well as on application to the analysis of 12 illicit drugs in ten real samples demonstrate the applicability to environment monitoring analysis.


Asunto(s)
Drogas Ilícitas , Estructuras Metalorgánicas , Benceno , Cromatografía Liquida , Estructuras Metalorgánicas/química , Microesferas , Poliestirenos/química , Extracción en Fase Sólida/métodos , Espectrometría de Masas en Tándem , Compuestos de Vinilo , Aguas Residuales/química
15.
Environ Sci Pollut Res Int ; 29(51): 77724-77736, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35687289

RESUMEN

This study examines the dynamic causality between the carbon emission market and the clean energy market, using an information flow-based, quantitative Liang causality analysis which is firmly grounded on physics and derived from first principles. The dynamic causal relationships between European Union Allowance (EUA) prices and clean energy index allow us to explore whether the causality in return or in variance from CO2 emission allowances to the clean energy index is time-varying. The results show that the causal relationships in return and in variance between EUA and Clean Energy Index (CEI) are drastically time-varying. For the causality in return, a significant unidirectional long-term and stable causality from CEI to EUA is identified after March 2020. For that in variance, a bidirectional causality is found after March 2020, but values after 2020 are opposite to those in return. It seems when fluctuations in the clean energy market are low, the clean energy market has a weak causal effect on the carbon emission market but when volatility in the clean energy market is increasing, causalities between the two markets are significantly strengthened. These results obtained through this rigorous causality analysis can serve as a reference for academics, market participants, and policymakers to understand the underlying links between EUA prices and clean energy index.


Asunto(s)
Dióxido de Carbono , Desarrollo Económico , Humanos , Carbono , Causalidad
16.
J Anal Methods Chem ; 2021: 8878247, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33489420

RESUMEN

An analysis method was established to determine 14 organophosphorus ester (OPE) flame retardants in fall protection equipment by combining accelerated solvent extraction (ASE) and solid-phase extraction (SPE) with high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). The ASE parameters were optimized as follows: static extraction with acetonitrile at 80°C for 5 min for two cycles. The combined extract was purified with the ENVI-18 cartridge before further analysis. A HILIC column was used to separate the OPEs using an acetonitrile/water mixture as the mobile phase with the detection by the electrospray ionization mass spectrometry, which was operated under the positive mode. Under optimized conditions, the limit of detection for the target OPEs ranged in 0.015-1.33 ng/g, with a spike recovery of 71.6%-114% and a relative standard deviation of 0.8%-11.2%. The developed method was used to analyze OPEs in fall protection equipment (safety helmets and ropes), where OPEs were all detectable. Safety ropes displayed a higher concentration of OPEs than ones in safety helmets, with the pollutants being mainly triphenyl phosphate, 2-ethylhexyl diphenyl phosphate (EHDPP), tri(2-ethylhexyl) phosphate, and tri-n-butyl phosphate in the range of 11.07 ng/g‒815.53 ng/g. The EHDPP was the dominant compound in safety helmets with the concentration from 26.84 to 95.29 ng/g, while the other OPEs in safety helmets were lower than 5.136 ng/g. The potential health and environmental risks of these fall protection equipment during their use and disposal call for further attention.

17.
J Chromatogr A ; 1635: 461765, 2021 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-33285418

RESUMEN

In the design of highly ordered (covalent organic frameworks) COFs with "ordered domains size and orientation" construction in a well-defined arrangement, the molecular monomers are the key factors. Here, the effect of molecular monomers on the construction of COFs has been studied, and two kinds of molecular monomers, i.e., ethanediamine (flexible amine ligand) and 4,4'-diaminobiphenyl (rigid amine ligand) have been used for developing sheet-like COFs-I and sheet-like COFs-II, respectively. Furthermore, they have been evaluated in the dispersive solid phase extraction (dSPE) procedure for textiles prior to the analysis of alkylphenol by liquid chromatography-tandem quadrupole mass spectrometry (LC-MS/MS). The results showed that, the optimal usage amount of sheet-like COFs-II used in the dSPE procedure was less than that of sheet-like COFs-I, which may be explained by much higher adsorption capacity of sheet-like COFs via hydrogen-bonding and π-π stacking interactions. Rectilinear calibration graphs were obtained for 4-(tert-octyl)-phenol (4-tOP) and 4-nonylphenol (4-NP) in the range 0.2-20 µg/kg with determination coefficient (r2) higher than 0.9990, and the limits of detection (LODs) of 4-tOP and 4-NP were 0.039 µg/kg and 0.048 µg/kg, respectively. The developed method has been successfully applied to analysis of 50 textile samples, in which 4-tOP and 4-NP were found in six samples with concentrations in the range of 1.6 µg/kg-20.9 µg/kg.


Asunto(s)
Técnicas de Química Analítica/métodos , Estructuras Metalorgánicas/química , Fenoles/aislamiento & purificación , Textiles , Adsorción , Cromatografía Liquida , Límite de Detección , Extracción en Fase Sólida , Espectrometría de Masas en Tándem
18.
Sci Rep ; 10(1): 17846, 2020 10 20.
Artículo en Inglés | MEDLINE | ID: mdl-33082472

RESUMEN

In order to understand the clinical manifestations and incidence of gastrointestinal symptoms of coronavirus disease (COVID-19) in children and discuss the importance of fecal nucleic acid testing.We retrospectively analyzed studies on gastrointestinal symptoms and fecal nucleic acid detection in pediatric COVID-19 patients from January 1, 2020 to August 10, 2020, including prospective clinical studies and case reports. The results of fecal nucleic acid detection were analyzed systematically. Stata12.0 software was used for meta-analysis.The results showed that the most common gastrointestinal symptoms in children with COVID-19 were vomiting and diarrhea, with a total incidence of 17.7% (95% Cl 13.9-21.5%). However, the prevalence of gastrointestinal symptoms in other countries (21.1%, 95% CI 16.5-25.7%) was higher compared to China (12.9%, 95% CI 8-17.7%). In Wuhan, the pooled prevalence was much higher (41.3%, 95% CI 3.2-79.4%) compared to areas outside Wuhan in China (7.1%, 95% CI 4.0-10.3%). The positive rate of fecal nucleic acid testing in COVID-19 children was relatively high at 85.8% (91/106). Additionally, 71.2% (52/73) were still positive for fecal nucleic acid after respiratory tract specimens turned negative. One and two weeks after the respiratory tract specimens turned nucleic acid-negative, 45.2% (33/73) and 34.2% (25/73) patients, respectively, remained fecal nucleic acid-positive. The longest interval between the respiratory tract specimens turning negative and fecal specimens turning negative exceeded 70 days. Conclusions and relevance: gastrointestinal symptoms in pediatric COVID-19 are relatively common. Attention should be paid to the detection of fecal nucleic acids in children. Fecal nucleic acid-negative status should be considered as one of the desegregation standards.


Asunto(s)
Betacoronavirus/genética , Infecciones por Coronavirus/diagnóstico , Heces/virología , Enfermedades Gastrointestinales/diagnóstico , Neumonía Viral/diagnóstico , Betacoronavirus/aislamiento & purificación , COVID-19 , Niño , Infecciones por Coronavirus/complicaciones , Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/virología , Diarrea/complicaciones , Diarrea/diagnóstico , Diarrea/epidemiología , Enfermedades Gastrointestinales/complicaciones , Enfermedades Gastrointestinales/epidemiología , Humanos , Pandemias , Neumonía Viral/complicaciones , Neumonía Viral/epidemiología , Neumonía Viral/virología , Prevalencia , Pronóstico , ARN Viral/metabolismo , SARS-CoV-2
19.
Medicine (Baltimore) ; 99(34): e21860, 2020 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-32846837

RESUMEN

BACKGROUND: The use of fluoroquinolone antibiotics has been restricted in children because of their potential to cause adverse musculoskeletal events. This study was performed to systematically evaluate whether there is a difference between fluoroquinolone and non-fluoroquinolone antibiotics in terms of their associated risk of adverse musculoskeletal events in children. METHODS: Cochrane Library, Embase, and PubMed databases were used to retrieve studies related to fluoroquinolone and non-fluoroquinolone-induced musculoskeletal adverse events in children. A meta-analysis was performed using Stata 11. RESULTS: A total of 10 studies were included in the analysis. The combined results showed that there was no statistical difference between fluoroquinolone and non-fluoroquinolone groups in terms of musculoskeletal adverse events in children (risk ratio = 1.145, 95% confidence interval = 0.974 - 1.345, P = .101). Subgroup analysis was performed using a random-effects model. Here, the effects on the trovafloxacin and levofloxacin groups were significantly different from that of the control group. However, musculoskeletal adverse events due to either drug was not reported after long-term follow-up. CONCLUSIONS: The results showed that fluoroquinolone and non-fluoroquinolone antibiotics were not different in terms of their ability to cause musculoskeletal adverse events in children. For this reason, fluoroquinolone antibiotics can be used in children as appropriate. PROSPERO REGISTRATION NUMBER: CRD42019133900.


Asunto(s)
Antibacterianos/efectos adversos , Infecciones Bacterianas/tratamiento farmacológico , Fluoroquinolonas/efectos adversos , Sistema Musculoesquelético/efectos de los fármacos , Adolescente , Antibacterianos/uso terapéutico , Estudios de Casos y Controles , Niño , Preescolar , Femenino , Fluoroquinolonas/uso terapéutico , Humanos , Lactante , Recién Nacido , Levofloxacino/efectos adversos , Levofloxacino/uso terapéutico , Masculino , Naftiridinas/efectos adversos , Naftiridinas/uso terapéutico , Estudios Retrospectivos , Sensibilidad y Especificidad , Inhibidores de Topoisomerasa II/efectos adversos , Inhibidores de Topoisomerasa II/uso terapéutico
20.
Sci Total Environ ; 706: 135961, 2020 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-31841851

RESUMEN

Personal care and cosmetic products (PCPs) are the primary exposure pathway of humans to parabens and their safety has become a public concern. However, sample pretreatment of PCPs is a great challenge due to their complexities and diversity. In this study, epoxide modified molecularly imprinted polymers (MIPs) were synthesized using ethylparaben as a template, methacrylic acid and isobutyl vinyl ether as co-monomers and glycidilmethacrylate as a post-modified monomer. MIP layer open-tubular tubes were prepared by modifying branched polyethylenimine and then grafting MIPs onto the inner surface of Teflon capillary tubes. The tube was coiled to effectively increase mass transfer and coupled to an HPLC-UV system for parabens detection in PCPs. Matrix interference was significantly decreased while efficient enrichment and recoveries were obtained. Under optimized conditions, the linear range for parabens detection was 0.5-600 ng mL-1 with detection limits of 0.2 to 0.3 ng mL-1. The system was used to study the contents of parabens in popular PCPs. The concentrations of parabens in 108 PCPs ranged from <0.5 ng g-1 to 2856 µg g-1 with geometric mean of 250.3 µg g-1. Almost all of the products contained at least one kind of parabens; methyl paraben (geometric mean: 182.9 µg g-1) and n-propyl paraben (geometric mean: 42.5 µg g-1) were the predominant compounds had been found in the samples. This method could be useful for human exposure assessment towards parabens.


Asunto(s)
Cosméticos , Cromatografía Líquida de Alta Presión , Impresión Molecular , Parabenos , Polímeros
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