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1.
Pharmaceutics ; 16(1)2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38276519

RESUMO

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.

2.
Chemosphere ; 319: 137995, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36731669

RESUMO

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.


Assuntos
Poluentes Atmosféricos , Compostos Orgânicos Voláteis , Catálise , Oxirredução , Óxidos
3.
Pestic Biochem Physiol ; 188: 105287, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36464340

RESUMO

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.


Assuntos
Cistamina , Fungicidas Industriais , Autofagia , Fungicidas Industriais/farmacologia , Permeabilidade
4.
Analyst ; 147(22): 5011-5017, 2022 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-36278793

RESUMO

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.


Assuntos
Grafite , Animais , Nitrofurazona , Técnicas Eletroquímicas/métodos , Eletrodos , Oxirredução , Carbono
5.
J Chromatogr A ; 1682: 463505, 2022 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-36152484

RESUMO

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.


Assuntos
Drogas Ilícitas , Estruturas Metalorgânicas , Benzeno , Cromatografia Líquida , Estruturas Metalorgânicas/química , Microesferas , Poliestirenos/química , Extração em Fase Sólida/métodos , Espectrometria de Massas em Tandem , Compostos de Vinila , Águas Residuárias/química
6.
Environ Sci Pollut Res Int ; 29(51): 77724-77736, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35687289

RESUMO

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.


Assuntos
Dióxido de Carbono , Desenvolvimento Econômico , Humanos , Carbono , Causalidade
7.
Entropy (Basel) ; 23(9)2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34573797

RESUMO

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.

8.
J Anal Methods Chem ; 2021: 8878247, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33489420

RESUMO

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.

9.
J Chromatogr A ; 1635: 461765, 2021 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-33285418

RESUMO

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.


Assuntos
Técnicas de Química Analítica/métodos , Estruturas Metalorgânicas/química , Fenóis/isolamento & purificação , Têxteis , Adsorção , Cromatografia Líquida , Limite de Detecção , Extração em Fase Sólida , Espectrometria de Massas em Tandem
10.
Sci Rep ; 10(1): 17846, 2020 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-33082472

RESUMO

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.


Assuntos
Betacoronavirus/genética , Infecções por Coronavirus/diagnóstico , Fezes/virologia , Gastroenteropatias/diagnóstico , Pneumonia Viral/diagnóstico , Betacoronavirus/isolamento & purificação , COVID-19 , Criança , Infecções por Coronavirus/complicações , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/virologia , Diarreia/complicações , Diarreia/diagnóstico , Diarreia/epidemiologia , Gastroenteropatias/complicações , Gastroenteropatias/epidemiologia , Humanos , Pandemias , Pneumonia Viral/complicações , Pneumonia Viral/epidemiologia , Pneumonia Viral/virologia , Prevalência , Prognóstico , RNA Viral/metabolismo , SARS-CoV-2
11.
Medicine (Baltimore) ; 99(34): e21860, 2020 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-32846837

RESUMO

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.


Assuntos
Antibacterianos/efeitos adversos , Infecções Bacterianas/tratamento farmacológico , Fluoroquinolonas/efeitos adversos , Sistema Musculoesquelético/efeitos dos fármacos , Adolescente , Antibacterianos/uso terapêutico , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Fluoroquinolonas/uso terapêutico , Humanos , Lactente , Recém-Nascido , Levofloxacino/efeitos adversos , Levofloxacino/uso terapêutico , Masculino , Naftiridinas/efeitos adversos , Naftiridinas/uso terapêutico , Estudos Retrospectivos , Sensibilidade e Especificidade , Inibidores da Topoisomerase II/efeitos adversos , Inibidores da Topoisomerase II/uso terapêutico
12.
Mikrochim Acta ; 187(2): 142, 2020 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-31965326

RESUMO

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.


Assuntos
Colorimetria/métodos , Estruturas Metalorgânicas/química , Impressão Molecular , Mimetismo Molecular , Bifenil Polibromatos/análise , Polímeros/química , Adsorção , Benzidinas/metabolismo , Enzimas , Peróxido de Hidrogênio/química , Limite de Detecção
13.
J Ethnopharmacol ; 246: 112225, 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31509781

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Our previous research found that Sangguayin (SGY) deccoction made by four dietary and medicinal plant components (Leaf of Morus alba L., Root of Pueraria lobata (Willd.) Ohwi., Root of Dioscorea opposita Thunb. and Fruit of Momordica charantia L.) showed significant anti-diabetic effects on db/db mice and high fat diet induced obese mice. Nevertheless, it remained unclear what the role of gut microbiota in the hypoglycaemia effects of SGY. AIMS OF THE STUDY: This study aimed to examine the beneficial effects of Sangguayin Deccoction against metabolic syndrome and and its regulating role in gut microbiota and hepatic metabolome. MATERIALS AND METHODS: C57BL/6J mice were divided to a normal chow diet (NCD), high-fat diet (HFD), and high-fat diet with Sangguayin Decoction (HFD-SGY, oral dose of 250 mg/kg/d) for 16 weeks. Next generation sequencing was applied for analyzing the gut microbial community of colonic contents. Further, untargeted metabolomic analysis based on LC-MS was used for determining the changes of hepatic metabolites. Hepatic genes expression were measured by quantitative PCR. RESULTS: SGY supplement decreased blood glucose level and glucose intolerance. Illumina MiSeq sequencing revealed that SGY increased Verrucomicrobia phylum, resulting in a bloom of Akkermansia, and eventually upregulated the contents of Lachoclostridium and Roseburia. Additionally, dietary SGY decreased bacteria including Faecalibaculum, and Blautia. Moreover, the hepatic lipid metabolism was notably altered by SGY treatment. The oxidation of glutamione metabolism idecreasees, production of poly-unsaturated fatty acid (PUFA) got significant increase in liver tissue. The reversion of PUFA metabolism by SGY may act through PPARα mediated Fads1 and Fads2 gene expression. The altered metabolites in liver showed intimate correlatship with modified genera. CONCLUSION: Data indicated that SGY reshaped gut microbial structure and improved PUFA metabolism. These functions of SGY may alter hepatic lipid metabolism, conferring preventative effects against high-fat diet induced metabolic syndrome.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Microbioma Gastrointestinal/efeitos dos fármacos , Obesidade/induzido quimicamente , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Animais , Bactérias/classificação , Bactérias/efeitos dos fármacos , Dieta Hiperlipídica , Medicamentos de Ervas Chinesas/química , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fitoterapia , Extratos Vegetais/química
14.
Sci Total Environ ; 706: 135961, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31841851

RESUMO

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.


Assuntos
Cosméticos , Cromatografia Líquida de Alta Pressão , Impressão Molecular , Parabenos , Polímeros
15.
J Chromatogr B Analyt Technol Biomed Life Sci ; 1126-1127: 121708, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31437773

RESUMO

Analysis of acidic pharmaceuticals in complex biological samples is a challenging and formidable task due to the existence of interfering constituents within the sample matrices. Therefore, in order to avoid analytical column clogging and suppression/enhancement of signals of the analyte of interest, herein a simple, cost-effective and quick online ion chromatography based clean-up setup was introduced. This system was further coupled with a cost-effective homemade photochemically induced fluorimetric (PIF) setup for direct online conversion of non-fluorescent acidic pharmaceutical drugs into their respective fluorescent species. This advantageous system was favorably applied for the determination of four non-fluorescent acidic compounds in two complex biological samples (human serum and oral fluid) with minimum labor and organic solvent consumption. At optimized conditions, the developed method has shown good sensitivity, selectivity, satisfactory recoveries (88.68-102.14%) and low limits of detection (0.35-8.10 µg/L) with minimum or zero matrix effect.


Assuntos
Cromatografia por Troca Iônica/métodos , Fluorometria/métodos , Preparações Farmacêuticas/análise , Ácidos/análise , Ácidos/sangue , Ácidos/química , Corantes Fluorescentes/química , Humanos , Limite de Detecção , Modelos Lineares , Preparações Farmacêuticas/sangue , Preparações Farmacêuticas/química , Reprodutibilidade dos Testes , Saliva/química
16.
J Sep Sci ; 41(22): 4096-4104, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30230241

RESUMO

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%.


Assuntos
Poluentes Ambientais/química , Neonicotinoides/análise , Ácidos Nicotínicos/análise , Cromatografia por Troca Iônica , Monitoramento Ambiental , Estrutura Molecular , Processos Fotoquímicos , Espectrometria de Fluorescência
17.
Sci Rep ; 8(1): 12327, 2018 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-30120273

RESUMO

Nowadays, there are rising concerns about the extensive use of the antibiotics such as chloramphenicol (CAP), has threatened the human life in the form of various vicious diseases. The limited selectivity and sensitivity of confirmatory techniques (UV and electrochemical) and non-fluorescence property of CAP make its determination a challenging task in the modern pharmaceutical analysis. In order to redeem the selective, sensitive and cost-effective fluorescence methodology, here by the dual role of synthesized porous SnO2 nanoparticles were exploited; (i) a porous sorbent in a µ-QuEChERS based sample preparation and as (ii) a stimulant for the transformation of non-fluorescent analytes namely CAP and p-nitrophenol (p-NP) into their respective fluorescent product. We report a green, simple, selective and cost effective ion chromatographic method for CAP sensitive determination in three complex matrices including milk, human urine and serum. The synthesized sorbent not only selectively adsorbed and degraded the matrix/interferences but also selectively reduced the non-fluorescent antibiotic CAP into a fluorescent species. This developed ion chromatographic method exhibited good selectivity, linearity (r2 ≥ 0.996) and limit of detection (LOD) was in the range 0.0201-0.0280 µg/kg. The inter- and intraday precisions were also satisfactory having a relative standard deviation (RSDs) less than 14.96% and excellent recoveries of CAP in the range of 78.3-100.2% were retrieved in various complex samples.


Assuntos
Antibacterianos/análise , Cloranfenicol/análise , Cromatografia por Troca Iônica , Nanopartículas/química , Animais , Humanos , Limite de Detecção , Metabolômica/métodos , Leite/química , Porosidade , Reprodutibilidade dos Testes
18.
RSC Adv ; 8(17): 9277-9286, 2018 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-35541852

RESUMO

There are increasing concerns about the dietary risks of neonicotinoids (NNIs); therefore their sensitive and accurate determination in dietary products is indispensable. However, the complex composition of agricultural food matrixes makes their extraction and quantitative determination a challenging task. Realizing this need, we herein report a simple, cost-effective, selective and sensitive fluorescence analytical workflow for analyses of two non-fluorescent neonicotinoids imidacloprid (IMI) and clothianidin (CLT) in six complex food samples (honey, ginger, durian, apple, tomato, cucumber) by online clean-up of sample extracts using two-dimensional ion chromatography (2D-IC) and a subsequent online post column UV induced fluorescence detection system. This online clean-up setup has proven advantageous to improve the limit of detection, potentially diminish matrix effects, and reduce analysis time and labor. The developed method showed excellent analytical figures of merit including linearity, selectivity, repeatability, recovery, and resolution for analysis of IMI and CLT in food samples.

19.
Blood Coagul Fibrinolysis ; 26(5): 564-71, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25828970

RESUMO

The aim of this study was to investigate causative mutations of two unrelated symptomatic Chinese children with dysfibrinogenemia and their family members.Fibrinogen genes, including FGA, FGB and FGG of all participants were PCR-amplified, followed by direct sequencing. Precipitated plasma fibrinogen of some family members was analyzed by western blotting, fibrin polymerization and scanning electron microscopy (SEM).Proband 1 associated with frequent epistaxis was identified to harbor a heterozygous Arg275Cys mutation in FGG, along with a polymorphism Arg448Lys in FGB. Proband 2 with apparently prolonged thrombin time and very low functional fibrinogen had undergone both spontaneous intracranial hemorrhages and deep venous thrombosis. Sequencing of all proximal promoters, coding regions, introns and 3'-untranslated region using genomic DNA of Proband 2 yielded no mutation in three fibrinogen genes. Western blotting of this patient's precipitated plasma fibrinogen detected no truncated protein. Fibrinogen polymerization curve showed prolonged lag phase and severely decreased final turbidity, and SEM observations of fibrin clots made from Proband 2 revealed an abnormal sponge-like mass with large pores. We speculate that other underlying mechanisms responsible for dysfibrinogenemia such as abnormal posttranscriptional processing or posttranslational modification, which are independent of detectable mutations in the genomic DNA sequence, may exist.


Assuntos
Afibrinogenemia/genética , Fibrinogênio/genética , Povo Asiático , Pré-Escolar , Humanos , Masculino , Mutação
20.
J Cell Mol Med ; 18(7): 1334-43, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24758696

RESUMO

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.


Assuntos
Antiarrítmicos , Arritmias Cardíacas/prevenção & controle , MicroRNAs/genética , Infarto do Miocárdio/prevenção & controle , Miócitos Cardíacos/metabolismo , Receptores Adrenérgicos beta 1/química , Regiões 3' não Traduzidas/genética , Animais , Arritmias Cardíacas/genética , Arritmias Cardíacas/patologia , Biomarcadores/análise , Western Blotting , Células Cultivadas , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Frequência Cardíaca , Masculino , Infarto do Miocárdio/genética , Infarto do Miocárdio/patologia , Miócitos Cardíacos/patologia , RNA Mensageiro/genética , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase em Tempo Real , Receptores Adrenérgicos beta 1/genética , Receptores Adrenérgicos beta 1/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
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