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1.
Environ Res ; 252(Pt 1): 118768, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38521355

RESUMO

Chlorinated paraffins (CPs) are hazardous to humans, and dietary intake acts as the primary pathway for human exposure to CPs. Takeout food is popular worldwide, but the presence of CPs in takeout food and its packaging is unclear. In this study, the concentrations and distributions of short- and median-chain CPs (SCCPs and MCCPs, respectively) were measured in 97 samples of four categories of takeout food and 33 samples of three types of takeout packaging. The SCCP and MCCP median concentrations for the takeout food samples were 248 and 339, 77.2 and 98.2, 118 and 258, 42.9 and 64.4 ng/g wet weight in meat, starch, half meat/half starch, and vegetables, respectively. Takeout food contained higher concentrations of SCCPs than MCCPs. The dominant SCCP and MCCP congener groups in takeout food were C10Cl6-7 and C14Cl7-8, respectively. The CP concentrations in takeout food were lower than those in packaging. The SCCP and MCCP median concentrations, respectively, in packaging were 9750 and 245 ng/g in polypropylene, 2830 and 135 ng/g in paper, and 2060 and 119 ng/g in aluminum foil. The concentrations of SCCPs and MCCPs were comparable in aluminum foil, whereas the concentrations of SCCPs were higher than those of MCCPs in polypropylene and paper. Correlations between CP concentrations in the takeout food and packaging indicated that CPs in packaging were potentially an important source of CPs in the takeout food. A dietary exposure risk assessment showed the takeout food posed a low risk for human exposure to CPs; however, high-frequency consumption may pose a health risk. This study clarified the current contamination situation in takeout food in Beijing, China. The resulting data could be used to prevent human exposure to CPs through dietary intake and to facilitate the market's control over the quality of takeout food.


Assuntos
Exposição Dietética , Contaminação de Alimentos , Embalagem de Alimentos , Parafina , Exposição Dietética/análise , Contaminação de Alimentos/análise , Parafina/análise , Humanos , Medição de Risco , Pequim , Hidrocarbonetos Clorados/análise , China
2.
J Environ Manage ; 354: 120343, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38364541

RESUMO

Soil aggregates are essential functional units involved in soil carbon sequestration, particularly in saline-sodic soils prone to severe carbon loss. In the present study, the distribution of aggregate-associated carbon fractions and their influencing factors were investigated after artificial utilization of saline soil in the Songnen Plain, Northeast China. Physicochemical properties, enzymatic activities, and bacterial communities were measured in various hierarchical aggregates among two natural land-use types (saline wasteland and degraded grassland) and three anthropogenic land-use types (artificial forest, upland field, and paddy field). The results indicated that, compared to saline wasteland, anthropogenic land use was witnessed an increase in macroaggregate proportions, and PF in large macroaggregates increased the most, while UF and FL were mainly increased in small macroaggregates. After transforming from natural land to anthropogenic land, the aggregate-associated carbon fractions (total organic carbon, readily soluble organic carbon, dissolved organic carbon, and microbial biomass carbon) increased, especially in small macroaggregates. All enzyme activities increased after artificial utilization, hydrolase (urease, amylase, and invertase), catalase, and ß-glucosidase activities were highest in the small macroaggregates. Bacterial biomass was increased in all three aggregate types compared to natural land. Due to the influence of various factors on soil carbon storage, through partial least squares path modeling revealed that large macroaggregates were conducive to carbon storage. These findings suggested that artificial utilization of saline soil can increase large macroaggregate proportions and the abundance of aggregate-associated carbon, resulting in increased soil carbon stocks, with PF having the greatest carbon sequestration capacity.


Assuntos
Carbono , Solo , Carbono/análise , Solo/química , Sequestro de Carbono , China , Florestas
3.
J Environ Sci (China) ; 139: 138-149, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38105042

RESUMO

Soil acidification is a major threat to agricultural sustainability in tropical and subtropical regions. Biodegradable and environmentally friendly materials, such as calcium lignosulfonate (CaLS), calcium poly(aspartic acid) (PASP-Ca), and calcium poly γ-glutamic acid (γ-PGA-Ca), are known to effectively ameliorate soil acidity. However, their effectiveness in inhibiting soil acidification has not been studied. This study aimed to evaluate the effect of CaLS, PASP-Ca, and γ-PGA-Ca on the resistance of soil toward acidification as directly and indirectly (i.e., via nitrification) caused by the application of HNO3 and urea, respectively. For comparison, Ca(OH)2 and lignin were used as the inorganic and organic controls, respectively. Among the materials, γ-PGA-Ca drove the substantial improvements in the pH buffering capacity (pHBC) of the soil and exhibited the greatest potential in inhibiting HNO3-induced soil acidification via protonation of carboxyl, complexing with Al3+, and cation exchange processes. Under acidification induced by urea, CaLS was the optimal one in inhibiting acidification and increasing exchangeable acidity during incubation. Furthermore, the sharp reduction in the population sizes of ammonia-oxidizing bacteria (AOB) and ammonia-oxidizing archaea (AOA) confirmed the inhibition of nitrification via CaLS application. Therefore, compared to improving soil pHBC, CaLS may play a more important role in suppressing indirect acidification. Overall, γ-PGA-Ca was superior to PASP-Ca and CaLS in enhancing the soil pHBC and the its resistance to acidification induced by HNO3 addition, whereas CaLS was the best at suppressing urea-driven soil acidification by inhibiting nitrification. In conclusion, these results provide a reference for inhibiting soil re-acidification in intensive agricultural systems.


Assuntos
Cálcio , Solo , Nitrificação , Amônia , Archaea , Ureia , Microbiologia do Solo , Concentração de Íons de Hidrogênio , Oxirredução
4.
Cell Mol Biol (Noisy-le-grand) ; 69(15): 132-135, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-38279474

RESUMO

This study aimed to analyze the expression of lymphocyte ratio (LY%) in different stages and clinical staging of COVID-19 and explore the relationship between peripheral blood lymphocyte (PBL) ratio and COVID-19 severity to provide reference for early intervention. For this purpose, a total of 125 patients with COVID-19 admitted to Hebei Provincial People's Hospital from February 1, 2020, to March 1, 2022, were reviewed and divided into moderate, severe, and critical groups by the severity to analyze and compare peripheral lymphocyte ratios of patients with different clinical typing. Results showed that lymphocyte count, lymphocyte percentage, CD3+ T-lymphocyte count, CD4+ T-lymphocyte count, and CD8+ T-lymphocyte count all decreased gradually with increasing severity (F = 27.84, P<0.05; F = 15.28, P<0.05; F = 46.12, P<0.05; F = 34.65, P<0.05); the absolute numbers of CD3+, CD4+ and CD8+ cells in peripheral blood were higher in the recovery phase than in the acute phase (P<0.05). In conclusion, COVID-19 may cause a decrease in the number of lymphocytes, and the decrease in the number of lymphocytes and T-lymphocyte subsets may predict the severity of the disease. The fewer lymphocytes there are, the more likely they are to progress to the severe type and the worse the prognosis.


Assuntos
COVID-19 , Humanos , Subpopulações de Linfócitos T , Linfócitos T CD8-Positivos , Contagem de Linfócitos , Hospitalização
5.
Luminescence ; 38(10): 1729-1737, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37400417

RESUMO

Glyphosate, the most used herbicide in the world, has a residue problem that cannot be ignored. However, glyphosate itself does not have fluorescence emission and lacks the conditions for fluorescence detection. In this work, a rapid and selective fluorescence detection method of glyphosate was designed by an 'on-off-on' fluorescent switch based on a luminous covalent organic framework (L-COF). Only the fixed concentration of Fe3+ as an intermediate could trigger the fluorescent switch and no incubation step was required. The proposed method showed good accuracy with a correlation coefficient of 0.9978. The method's limits of detection and quantitation were 0.88 and 2.93 µmol/L, which were lower than the maximum allowable residue limits in some regulations. Environmental water samples and tomatoes were selected as actual samples to verify the application in a complex matrix. A satisfactory mean recovery from 87% to 106% was gained. Furthermore, Fe3+ could induce fluorescence quenching of L-COF through the photo-induced electron transfer (PET) effect, while the addition of glyphosate could block the PET effect to achieve detection. These results demonstrated the proposed method had abilities to detect glyphosate and broaden the application of L-COF.


Assuntos
Estruturas Metalorgânicas , Estruturas Metalorgânicas/química , Espectrometria de Fluorescência , Corantes , Glicina/química , Glifosato
6.
Molecules ; 28(12)2023 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-37375277

RESUMO

Terbinafine, an inhibitor of squalene epoxidase in ergosterol biosynthesis, is chiefly utilized as an antifungal medication with potential uses in pesticide applications. This study explores the fungicidal efficacy of terbinafine against prevalent plant pathogens and confirms its effectiveness. To augment its water solubility, five ionic salts of terbinafine were synthesized by pairing them with organic acids. Among these salts, TIS 5 delivered the most impressive results, amplifying the water solubility of terbinafine by three orders of magnitude and lessening its surface tension to facilitate better dispersion during spraying. The in vivo experiments on cherry tomatoes showed that TIS 5 had a superior therapeutic activity compared to its parent compound and two commonly used broad-spectrum fungicides, pyraclostrobin and carbendazim. The results highlight the potential of terbinafine and its ionic salts, particularly TIS 5, for use as fungicides in agriculture due to their synergistic effects with furan-2-carboxylate.


Assuntos
Fungicidas Industriais , Sais , Terbinafina/farmacologia , Sais/farmacologia , Fungicidas Industriais/farmacologia , Naftalenos/farmacologia , Antifúngicos/farmacologia , Água
7.
Angew Chem Int Ed Engl ; 62(44): e202310671, 2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-37700683

RESUMO

By resorting to the principle of remote activation, we herein demonstrate the first photoredox catalyzed (3+3) dipolar cycloaddition of nitrones with aryl cyclopropanes. Key to the fidelity of the reaction resides in a facile manner of substrate activation by single-electron transfer (SET) oxidation with photoredox catalysis, and the reaction takes place through a stepwise cascade encompassing a three-electron-type nucleophilic substitution triggered cyclopropane ring-opening and a diastereoselective 6-endo-trig radical cyclization manifold. The reaction proceeds under mild conditions with excellent regio- and stereoselectivity, nicely complementing the well-developed Lewis acid catalyzed cycloaddition of donor-acceptor cyclopropanes. Other merits of the protocol include wide scope of aryl cyclopropanes with diversified substitution patterns and good functional-group compatibility. A mechanism involving an aryl radical cation promoted remote activation mode was also proposed and supported by mechanistic experiments.

8.
J Sep Sci ; 45(4): 908-918, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34897993

RESUMO

In this study, a 4-formylphenylboronic acid-modified cross-linked chitosan magnetic nanoparticle (FPBA@CCHS@Fe3 O4 ) was fabricated. The synthesized material was utilized as the magnetic solid-phase extraction adsorbent for the enrichment of six benzoylurea pesticides. In addition to B-N coordination, FPBA@CCHS@Fe3 O4 interacts with benzoylureas through hydrogen bonds and π-π stacking interaction on account of rich active groups (amino and hydroxyl) and aromatic rings in structure. Compared to traditional extraction methods, less adsorbent (20 mg) and reduced extraction time (3 min) were achieved. The adsorbent also exhibited good reusability (no less than 10 times). Coupled with a high-performance liquid chromatography-diode array detector, satisfactory recoveries (89.1-103.9%) and an acceptable limit of detection (0.2-0.7 µg/L) were obtained. Under optimized conditions, the established method was successfully applied to the tea infusion samples from six major tea categories with acceptable recoveries ranging from 76.8 to 110%, indicating its application potential for the quantitative detection of pesticides in complex matrices.

9.
BMC Infect Dis ; 21(1): 549, 2021 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-34112084

RESUMO

BACKGROUND: Due to the latent onset of novel coronavirus disease 2019 (COVID-19), it is important to identify patients with increased probabilities for disease progression early in order to implement timely medical strategies. This study aimed to identify the factors associated with increased COVID-19 severity and evaluate the current antiviral drugs, especially in severe patients. METHODS: This was a retrospective observational study performed at the No. 7 Hospital of Wuhan (Wuhan, China) with hospitalized patients confirmed with COVID-19 from January 11 to March 13, 2020. Multivariable logistic regression analysis was used to identify the associated factors of severe COVID. Treatments of antivirus drugs were collected and evaluated. RESULTS: Of the 550 patients, 292 (53.1%) were female and 277 (50.4%) were > 60 years old. The most common symptom was fever (n = 372, 67.7%), followed by dry cough (n = 257, 46.7%), and dyspnea (n = 237, 43.1%), and fatigue (n = 224, 40.7%). Among the severe patients, 20.2% required invasive ventilator support and 18.0% required non-invasive ventilator. The identified risk factors for severe cases were: age ≥ 60 years (odds ratio (OR) =3.02, 95% confidence interval (CI): 1.13-8.08, P = 0.028), D-dimer > 0.243 µg/ml (OR = 2.734, 95%CI: 1.012-7.387, P = 0.047), and low oxygenation index (OR = 0.984, 95%CI: 0.980-0.989, P < 0.001). In severe cases, the benefits (relief of clinical symptoms, clinical outcome, and discharge rate) of arbidol alone was 73.3%, which was better than ribavirin (7/17, 41.2%, P = 0.029). CONCLUSIONS: Age > 60 years, D-dimer > 0.243 µg/ml, and lower oxygenation index were associated with severe COVID-19. Arbidol might provide more clinical benefits in treating patients with severe COVID-19 compared with ribavirin.


Assuntos
Antivirais/uso terapêutico , Tratamento Farmacológico da COVID-19 , COVID-19/diagnóstico , Adulto , Idoso , COVID-19/patologia , COVID-19/fisiopatologia , China/epidemiologia , Feminino , Hospitais , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , SARS-CoV-2 , Índice de Gravidade de Doença
10.
J Sep Sci ; 44(15): 2957-2964, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34021970

RESUMO

Magnetic hyperbranched polyamideamine was carboxylated using succinic anhydride and modified further with 1-octyl-3-methylimidazole hexafluorophosphate successively. The morphology and chemical composition of the prepared material was characterized by transmission electron microscopy, scanning electron microscopy, Fourier transform infrared spectroscopy, Brunauer-Emmett-Teller measurement, X-ray photoelectron spectroscopy, etc. 1-Octyl-3-methylimidazole hexafluorophosphate modified magnetic hyperbranched polyamideamine was used as sorbent in the magnetic solid-phase extraction for the separation and enrichment of five pyrethroid insecticides from tea infusion. The magnetic solid-phase extraction method proposed in this article has low method detection limits (0.53-0.71 ng/mL), acceptable coefficient of determination (0.9992-0.9998), wide linear ranges (2.5-500.0 ng/mL), and good repeatability (intraday: 1.2-6.3%; interday: 1.6-5.4%). In the detection of five pyrethroid insecticides in tea infusion, relative recoveries were in the range from 87.7 to 114.7% with satisfactory relative standard deviations (0.2-7.4%). With the aid of quantum chemistry calculations, the interaction energy between the sorbent and five pyrethroid insecticides was calculated, which proved the necessity of the modification of 1-octyl-3-methylimidazole hexafluorophosphate.


Assuntos
Imidazóis/química , Inseticidas/isolamento & purificação , Magnetismo , Poliaminas/química , Piretrinas/isolamento & purificação , Chá/química , Espectroscopia Fotoeletrônica , Teoria Quântica
11.
J Sep Sci ; 44(20): 3830-3839, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34431614

RESUMO

Perfluoro octanoic acid was modified on the surface of magnetic hyperbranched polyamideamine by acid amine condensation. The morphology and chemical composition of perfluoro octanoic acid-modified magnetic hyperbranched polyamideamine was characterized by transmission electron microscopy, Fourier transform infrared spectroscopy, zeta potential, particle size analysis, Brunauer-Emmett-Teller measurement, and X-ray photoelectron spectroscopy. Perfluoro octanoic acid-modified magnetic hyperbranched polyamideamine was applied in magnetic solid phase extraction for the separation and enrichment of four fluorine-containing pesticides (indoxacarb, metaflumizone, cyflumetofen, and cyhalothrin). The magnetic solid phase extraction method based on perfluoro octanoic acid-modified magnetic hyperbranched polyamideamine has low method detection limits (0.30-0.49 µg/L), a satisfactory coefficient of determination (0.9995-0.9999), wide linear ranges (2.5-250 µg/L), and good repeatability (intraday: 2.6-4.7%; interday: 1.1-7.9%). The enrichment factors and extraction efficiences varied from 55 to 76 and 69 to 96%, respectively. The sorbent-to-sorbent reproducibility was in the range of 3.2-7.6%, indicating that the synthesis of the sorbent was reliable. For the detection of actual water samples, the relative recoveries were in the range from 80.1 to 114.4% with relative standard deviations less than 9.6%. The calculation results of quantum chemistry calculations showed that after the modification of perfluoro octanoic acid, the interaction between the sorbent and four fluorine-containing pesticides was stronger.

12.
J Sep Sci ; 44(9): 1931-1938, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33533566

RESUMO

Herein, a novel hyperbranched aromatic polyamide-coated magnetic sorbent was prepared by in situ polymerization on the surface of amino-functionalized Fe3 O4 nanoparticles. The magnetic sorbent was characterized by transmission electron microscopy, Fourier transform infrared spectroscopy, elemental analysis, Brunauer-Emmett-Teller measurement, and X-ray photoelectron spectroscopy, etc. The new magnetic sorbent was used in the magnetic solid-phase extraction for the detection of seven benzoylurea insecticides. Under optimum conditions, low method detection limits (0.56-1.20 ng/mL), acceptable coefficient of determination (0.9967-0.9996), wide linear ranges (2.5-500.0 ng/mL), and good repeatability (intraday: 2.0-7.3%; interday: 1.9-9.2%) were achieved. The magnetic solid-phase extraction method based on the new magnetic sorbent showed good reliability in the analysis of seven benzoylurea insecticides in real water samples, as the relative recoveries were in the range from 80.1 to 116.3% with satisfactory RSDs (0.1-9.8%). By means of density functional theory and semiempirical quantum mechanical, the binding configuration and interaction energy of hyperbranched aromatic polyamide and benzoylurea insecticides were calculated. The result of theoretical calculation revealed that the adsorption of benzoylurea insecticides by hyperbranched aromatic polyamide was derived from hydrogen bonding and π-π stacking. The contribution of π-π stacking was greater than that of hydrogen bond, which was confirmed by energy decomposition analysis.

13.
J Sep Sci ; 44(7): 1529-1536, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33506992

RESUMO

In this study, a novel method using a phosphonium-based deep eutectic solvent coupled with vortex-assisted liquid-liquid microextraction was investigated for the enrichment and separation of five benzoylurea insecticides in olive oil. The experimental factors affecting the extraction efficiency, including the extractant type, deep eutectic solvent volume, extraction time, and extraction mode, were optimized. Under optimal conditions, good linearity was observed for all target analytes, with correlation coefficients (r) ranging from 0.9971 to 0.9998; the limits of detection were in the range of 1.5 to 7.5 µg/L, and the recoveries of analytes using the proposed method ranged between 66.9 and 111.0%. The simple, rapid, and effective method was successfully applied for detecting target analytes in olive oil sample.


Assuntos
Inseticidas/análise , Azeite de Oliva/química , Compostos Organofosforados/química , Compostos de Fenilureia/análise , Microextração em Fase Líquida , Solventes/química
14.
Med Sci Monit ; 27: e930909, 2021 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-34873140

RESUMO

BACKGROUND Fine particulate matter (PM2.5) is the air pollutant that most threatens global public health. The purpose of this study was to observe the inflammatory and oxidative stress injury of multiple organs induced by PM2.5 in rats and to explore the tissue-protective effect of erdosteine. MATERIAL AND METHODS We randomly divided 40 male Wistar rats into a blank control group, a saline group, a PM2.5 exposure group, and an erdosteine intervention group. We assessed changes in organs tissue homogenate and biomarkers of inflammation and oxidative stress in serum and bronchoalveolar lavage fluid (BALF). RESULTS (1) The expressions of IL-6, IL-1ß, TNF-alpha, 8-OHdG, 4-HNE, and PCC in serum and BALF of the PM2.5 exposure group increased, but decreased after treatment with erdosteine, suggesting that erdosteine treatment attenuates inflammatory and oxidative stress injury. (2) The expression of γ-GCS in serum and lungs in the PM2.5 exposure group increased, but did not change significantly after treatment with erdosteine. This suggests that PM2.5 upregulates the level of γ-GCS, while erdosteine does not affect this protective response. (3) The expression of T-AOC in serum, lungs, spleens, and kidneys of the PM2.5 exposure group decreased, but increased after treatment with erdosteine. Our results suggest that PM2.5 can cause imbalance of oxidation/anti-oxidation in multiple organs, and erdosteine can alleviate this imbalance. CONCLUSIONS PM2.5 exposure can lead to inflammatory and oxidative stress damage in serum and organ tissues of rats. Erdosteine may be an effective anti-inflammatory and antioxidant that can reduce this injury.


Assuntos
Inflamação/prevenção & controle , Rim/efeitos dos fármacos , Lesão Pulmonar/prevenção & controle , Estresse Oxidativo/efeitos dos fármacos , Material Particulado/efeitos adversos , Baço/efeitos dos fármacos , Tioglicolatos/farmacologia , Tiofenos/farmacologia , Animais , Antioxidantes/farmacologia , Biomarcadores/metabolismo , Líquido da Lavagem Broncoalveolar , Modelos Animais de Doenças , Expectorantes , Masculino , Ratos , Ratos Wistar
15.
Cell Mol Biol (Noisy-le-grand) ; 66(6): 93-97, 2020 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-33040792

RESUMO

Lung cancer is a disease characterized by the uncontrolled growth of cells in lung tissue. If left untreated, cell growth can spread beyond the lungs to a process called metastasis and reach surrounding tissues or other organs. This experiment was set up to discuss and analyze the research value of joint detection of tumor markers including carcino-embryonic antigen (CEA), cytokeratin 19 fragments (CYFRA21-1) and neuron-specific enolase (NSE) in the diagnosis and pathological type of lung cancer. From November 2016 to February 2018, 378 cases of patients with lung cancer treated in our hospital and 200 cases of people with healthy physical examinations were collected. The electrochemical immunoluminescence method was adopted to detect the CEA, CYFRA21-1 and NSE. The detected positive rate and the concentration of CEA, CYFRA21-1 and NSE of lung cancer group were higher than that of the healthy physical examination group. The differences were of statistical significance (P<0.05); the detected positive rate of CEA and CYFRA21-1 and the concentration of CEA, CYFRA21-1 and NSE of squamous carcinoma group were higher than that of the adenocarcinoma group. The differences were of statistical significance (P<0.05). The CEA, CYFRA21-1 and NSE are related to the pathological type of lung cancer and can be regarded as related indicators to diagnose lung cancer.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/metabolismo , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos de Neoplasias/metabolismo , Antígeno Carcinoembrionário/metabolismo , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/metabolismo , Diagnóstico Diferencial , Feminino , Humanos , Queratina-19/metabolismo , Masculino , Pessoa de Meia-Idade
16.
J Sep Sci ; 43(2): 496-504, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31671238

RESUMO

Hyperbranched polytriazine functionalized with humic acid was prepared and developed as new sorbents for dispersive solid-phase extraction of three acaricides (clofentezine, fenpyroximate, and pyridaben) in tea samples combined with high-performance liquid chromatography detection. The sorbents were characterized by scanning electron microscopy, energy dispersive spectroscopy, Zeta-potential, and Fourier transform infrared spectroscopy. The extraction parameters (extraction time, ionic strength, desorption conditions) were optimized. The adsorption mechanism was evaluated utilizing Fourier transform infrared spectra. Under optimum conditions, satisfactory analytical performances were achieved, which included high precision (1.33-9.62%), low limits of detection (0.19-3.54 µg/L), and wide linear range (2.5-500 µg/L) for the analysis of the acaricides. Moreover, the proposed method proved highly effective for the determination of acaricides in tea samples, with the relative recoveries in the range of 65.20-108.13% and relative standard deviations < 9.87%. The method has great application potential for the detection of acaricides in tea samples.


Assuntos
Acaricidas/análise , Substâncias Húmicas/análise , Polímeros/química , Extração em Fase Sólida , Chá/química , Triazinas/química , Estrutura Molecular , Tamanho da Partícula , Propriedades de Superfície
17.
J Sep Sci ; 43(12): 2419-2428, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32175682

RESUMO

In this work, a novel extraction technique based on the effervescence-assisted dispersion and magnetic recovery of attapulgite/polypyrrole sorbents was developed for determining the concentrations of five pyrethroids in honey samples. The magnetic nanoparticles were synthesized by a one-pot method. Several experimental parameters that affected the extraction efficiency, including the dispersion conditions, pH, ionic strength, and desorption conditions, were investigated. Under optimal conditions, the calibration curves for the five pyrethroids in honey samples exhibited good linearity, with r2 values ranging from 0.9979 to 0.9990. The limits of detection varied between 0.21 and 0.34 µg/L. Satisfactory recoveries of 81.42-106.73% with intra- and interday relative standard deviations of less than 6.94 and 10.89%, respectively, were obtained. Moreover, the sorbents exhibited acceptable batch-to-batch repeatability in the range of 5.06-15.01%, and each sorbent could be reused for up to four extraction cycles without a significant loss in the extraction recovery.


Assuntos
Mel/análise , Compostos de Magnésio/química , Nanocompostos/química , Polímeros/química , Piretrinas/análise , Pirróis/química , Compostos de Silício/química , Extração em Fase Sólida , Adsorção , Fenômenos Magnéticos , Tamanho da Partícula , Propriedades de Superfície
18.
J Adv Nurs ; 76(12): 3623-3630, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32951241

RESUMO

AIM: This study aims to evaluate the safety and analgesic efficacy of pre-mixed nitrous oxide/oxygen mixture treatment of pain induced by dressing change for perianal abscess. DESIGN: This protocol is a randomized, double-blind, placebo-controlled trial. METHODS: This study will be implemented in the Hospital of Traditional Chinese Medicine. Subjects enrolled in this study are hospitalized patients who suffered from moderate to severe pain due to dressing change after incision and drainage. Two hundred patients will be selected and randomly assigned to either an intervention or a control group. The intervention group will get routine pain treatment plus pre-mixed nitrous oxide/oxygen mixture treatment and the control group will be treated with routine pain management plus medical air treatment. All these patients, medical staff and investigators are blind to the nature of the gas in each cylinder, which is randomized. Data will be collected at baseline (T0), 5 min (T1) after the starting of intervention and 5 min post intervention (T2) for each group. The primary outcome is the level of pain relief at T1 and T2. The secondary outcomes cover physiological parameters, adverse events, satisfaction of patients and health professionals and the acceptance from patients. DISCUSSION: Results of this study will be discussed and the safety and effect of nitrous oxide/oxygen treatment of pain induced by dressing change will be proven. IMPACT: When the finding of this study has an active effect on the treatment of pain caused by dressing change, it may provide more options for nursing staff to choose nurse-led analgesia techniques and then improving the level and quality of pain care as well as patients' overall satisfaction with the Anorectal Department in China.


Assuntos
Abscesso , Óxido Nitroso , Abscesso/terapia , Bandagens , China , Método Duplo-Cego , Humanos , Oxigênio , Dor/tratamento farmacológico , Dor/etiologia , Medição da Dor , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
19.
Exp Lung Res ; 45(1-2): 1-12, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31032652

RESUMO

Objective: To study the role of miR-34c-5p targeting CCL22 in affecting the progression of chronic obstructive pulmonary disease (COPD). Methods: The dual-luciferase reporter gene assay was applied to verify the targeting relationship of miR-34c-5p and CCL22. The rats were randomly assigned into Control, COPD, COPD + empty plasmids, COPD + agomir, COPD + CCL22 shRNA and COPD + agomir + CCL22 groups. COPD model was built by using cigarette smoke exposure and LPS instillation. After 28 days, the pulmonary function was examined. ELISA method was used to detect TNF-α and IL-8 levels in bronchoalveolar lavage fluid (BALF), HE staining and Masson staining to observe the pathomorphological changes of lung tissues, qRT-PCR and/or Western blot to determine miR-34c-5p and CCL22 levels, and immunohistochemical staining to measure the expression of MMP-9 and TIMP-1. Results: MiR-34c-5p could target CCL22 to down-regulate its expression. Both miR-34c-5p agomir and CCL22 shRNA could reduce breathing frequency (f), airway resistance (RI), and the levels of IL-8 and TNF-α in BALF of COPD rats with increased Cydn (dynamic lung compliance) and PIF (peak inspiratory flow). Besides, the inflammatory cell infiltration, rupture of partial alveolus, enlarged alveolar cavity, and increased deposition of collagen fibers were observed in COPD rat tissues, with rise in mean linear intercept (MLI) and reduction in mean alveolar number (MAN), which could be reversed by miR-34c-5p agomir or CCL22 shRNA. Conclusion: MiR-34c-5p may promote inflammation response and maintain the protease-antiprotease balance via targeting CCL22, which provides scientific basis for the clinical treatment of COPD.


Assuntos
Quimiocina CCL22/antagonistas & inibidores , MicroRNAs/farmacologia , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Animais , Líquido da Lavagem Broncoalveolar/química , Quimiocina CCL22/efeitos dos fármacos , Modelos Animais de Doenças , Inflamação , Substâncias Protetoras/farmacologia , Doença Pulmonar Obstrutiva Crônica/genética , Ratos , Fumaça/efeitos adversos
20.
J Sep Sci ; 42(8): 1610-1619, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30770622

RESUMO

In this work, a method for the analysis of benzoylurea insecticides, including hexaflumuron, flufenoxuron, lufenuron and chlorfluazuron, in tea samples by high-performance liquid chromatography with Fe3 O4 -hyperbranched polyester nanocomposite as the adsorbent for magnetic solid-phase extraction was developed. The magnetic nanocomposite was prepared and characterized by infrared spectroscopy, vibrating sample magnetometry, and scanning electron microscopy. The as-prepared nanocomposite was used as a sorbent for the extraction and preconcentration of pesticide residues in tea samples. The extraction and desorption conditions, including mass ratios of raw materials, amount of sorbent, pH value, extraction time, and desorption time, were investigated. Under the final conditions chosen for the analysis, good linearity was obtained for all the tested compounds, with R2 values of at least 0.9979. The limits of detection were determined in the range of 0.15-0.3 µg/L. The recovery obtained from the analysis of tea samples with various spiked concentrations was between 90.7 and 98.4%, with relative standard deviations (n = 4) lower than 4.1%. Furthermore, the present approach was successfully applied to the quantitative determination of residues of benzoylurea insecticides in real samples.


Assuntos
Benzamidas/isolamento & purificação , Cromatografia Líquida de Alta Pressão/métodos , Contaminação de Alimentos/análise , Inseticidas/isolamento & purificação , Compostos de Fenilureia/isolamento & purificação , Piridinas/isolamento & purificação , Extração em Fase Sólida/métodos , Chá/química , Adsorção , Benzamidas/análise , Inseticidas/análise , Magnetismo , Nanopartículas de Magnetita/química , Nanocompostos/química , Resíduos de Praguicidas/análise , Resíduos de Praguicidas/isolamento & purificação , Compostos de Fenilureia/análise , Poliésteres/química , Piridinas/análise , Extração em Fase Sólida/instrumentação
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