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1.
J Virol ; 98(5): e0019824, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38591879

RESUMEN

The involvement of secreted phospholipase A2s in respiratory diseases, such as asthma and respiratory viral infections, is well-established. However, the specific role of secreted phospholipase A2 group IIE (PLA2G2E) during influenza virus infection remains unexplored. Here, we investigated the role of PLA2G2E during H1N1 influenza virus infection using a targeted mouse model lacking Pla2g2e gene (Pla2g2e-/-). Our findings demonstrated that Pla2g2e-/- mice had significantly lower survival rates and higher viral loads in lungs compared to wild-type mice following influenza virus infection. While Pla2g2e-/- mice displayed comparable innate and humoral immune responses to influenza virus challenge, the animals showed impaired influenza-specific cellular immunity and reduced T cell-mediated cytotoxicity. This indicates that PLA2G2E is involved in regulating specific T cell responses during influenza virus infection. Furthermore, transgenic mice expressing the human PLA2G2E gene exhibited resistance to influenza virus infection along with enhanced influenza-specific cellular immunity and T cell-mediated cytotoxicity. Pla2g2e deficiency resulted in perturbation of lipid mediators in the lung and T cells, potentially contributing to its impact on the anti-influenza immune response. Taken together, these findings suggest that targeting PLA2G2E could hold potential as a therapeutic strategy for managing influenza virus infections.IMPORTANCEThe influenza virus is a highly transmissible respiratory pathogen that continues to pose a significant public health concern. It effectively evades humoral immune protection conferred by vaccines and natural infection due to its continuous viral evolution through the genetic processes of antigenic drift and shift. Recognition of conserved non-mutable viral epitopes by T cells may provide broad immunity against influenza virus. In this study, we have demonstrated that phospholipase A2 group IIE (PLA2G2E) plays a crucial role in protecting against influenza virus infection through the regulation of T cell responses, while not affecting innate and humoral immune responses. Targeting PLA2G2E could therefore represent a potential therapeutic strategy for managing influenza virus infection.


Asunto(s)
Subtipo H1N1 del Virus de la Influenza A , Pulmón , Infecciones por Orthomyxoviridae , Animales , Ratones , Infecciones por Orthomyxoviridae/inmunología , Infecciones por Orthomyxoviridae/virología , Subtipo H1N1 del Virus de la Influenza A/inmunología , Pulmón/virología , Pulmón/inmunología , Pulmón/patología , Humanos , Fosfolipasas A2 Grupo II/genética , Fosfolipasas A2 Grupo II/inmunología , Linfocitos T/inmunología , Ratones Noqueados , Inmunidad Celular , Ratones Endogámicos C57BL , Ratones Transgénicos , Carga Viral , Modelos Animales de Enfermedad , Inmunidad Humoral , Inmunidad Innata , Gripe Humana/inmunología , Gripe Humana/virología , Femenino
2.
Biomed Chromatogr ; 37(9): e5659, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37081728

RESUMEN

A QuEChERS (quick, easy, cheap, effective, rugged, and safe) technique using ultrahigh-performance liquid chromatography with tandem mass spectrometry for the analysis of spinosad (spinosyn A + spinosyn D), thiocyclam, and nereistoxin in cucumber was developed with mean recoveries of 93-104%, relative standard deviations of ≤9%, and limits of quantification of 0.01 mg/kg. Field trials of spinosad and thiocyclam were performed in 12 representative cultivating areas in China. Field trial results indicate that spinosyn A and spinosyn D easily dissipated in cucumber with half-lives of 2.48-6.24 and <3 days, respectively. Nereistoxin was produced after thiocyclam application and was more persistent than its parent. The terminal residues of spinosad were all below the maximum residue limits (0.2 mg/kg) in China, whereas the terminal concentration of nereistoxin (calculated as the stoichiometric equivalent of thiocyclam), which was much higher than that of thiocyclam, was far beyond the maximum residue limits of thiocyclam in cucumber (0.01 mg/kg) established by the European Union. The predicted no-effect concentrations of spinosyn A, spinosyn D, thiocyclam, and nereistoxin leaching into groundwater were estimated using China-PEARL (Pesticide Emission Assessment at Regional and Local scales) models after application. However, the dietary (food and water) exposure risk quotient for different populations was below 1 with a preharvest interval set at 5 days after the last application, indicating that the application of spinosad and thiocyclam in cucumber was unlikely to pose unacceptable risk for human health. This study provides data for the safe use of spinosad and thiocyclam in cucumber ecosystem.


Asunto(s)
Cucumis sativus , Agua Subterránea , Residuos de Plaguicidas , Humanos , Exposición Dietética/análisis , Grupos de Población , Ecosistema , Residuos de Plaguicidas/análisis , Medición de Riesgo , China
3.
Biomed Chromatogr ; 36(1): e5229, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34414593

RESUMEN

Phenthoate is a chiral organophosphate pesticide with a pair of enantiomers which differ in toxicity, behavior and insecticidal activity, and its acute toxicity on human health owing to the inhibition of acetylcholinesterase highlights the need for enantioselective detection of enantiomers. Therefore, this study aimed to establish a simple rapid method for separation and detection of phenthoate enantiomers in fruits, vegetables and grains. The enantiomers were separated using reversed-phase high-performance liquid chromatography-tandem mass spectrometry for the first time. Rapid chiral separation (within 9 min) of the target compound was achieved on a chiral OJ-RH column with the mobile phase of methanol-water = 85:15(v/v), at a flow rate of 1 ml/min and a column temperature of 30°C. Acetonitrile and graphitized carbon black were used as the extractant and sorbent for pretreatment, respectively. This method provides excellent linearity (correlation coefficient ≥0.9986), high sensitivity (limit of quantification 5 µg/kg and limit of detection <0.25 µg/kg), satisfactory mean recoveries (76.2-91.0%) and relative standard deviation (intra-day RSDs ranged from 2.0 to 7.9% and inter-day RSDs ranged from 2.4 to 8.4%). In addition, a field trial to explore the stereoselective degradation of phenthoate enantiomers in citrus showed that (-)-phenthoate degraded faster than its antipode, resulting in the relative accumulation of (+)-phenthoate.


Asunto(s)
Cromatografía de Fase Inversa/métodos , Compuestos Organotiofosforados , Residuos de Plaguicidas , Plantas Comestibles/química , Espectrometría de Masas en Tándem/métodos , Cromatografía Líquida de Alta Presión/métodos , Frutas/química , Límite de Detección , Modelos Lineales , Compuestos Organotiofosforados/análisis , Compuestos Organotiofosforados/química , Residuos de Plaguicidas/análisis , Residuos de Plaguicidas/química , Reproducibilidad de los Resultados , Estereoisomerismo
4.
J Virol ; 94(20)2020 09 29.
Artículo en Inglés | MEDLINE | ID: mdl-32796071

RESUMEN

Since the first outbreak in 2013, the influenza A (H7N9) virus has continued emerging and has caused over five epidemic waves. Suspected antigenic changes of the H7N9 virus based on hemagglutination inhibition (HI) assay during the fifth outbreak have prompted the update of H7N9 candidate vaccine viruses (CVVs). In this study, we comprehensively compared the serological cross-reactivities induced by the hemagglutinins (HAs) of the earlier CVV A/Anhui/1/2013 (H7/AH13) and the updated A/Guangdong/17SF003/2016 (H7/GD16). We found that although H7/GD16 showed poor HI cross-reactivity to immune sera from mice and rhesus macaques vaccinated with either H7/AH13 or H7/GD16, the cross-reactive neutralizing antibodies between H7/AH13 and H7/GD16 were comparably high. Passive transfer of H7/AH13 immune sera also provided complete protection against the lethal challenge of H7N9/GD16 virus in mice. Analysis of amino acid mutations in the HAs between H7/AH13 and H7/GD16 revealed that L226Q substitution increases the HA binding avidity to sialic acid receptors on red blood cells, leading to decreased HI titers against viruses containing HA Q226 and thus resulting in a biased antigenic evaluation based on HI assay. These results suggest that amino acids located in the receptor-binding site could mislead the evaluation of antigenic variation by solely impacting the receptor-binding avidity to red blood cells without genuine contribution to antigenic drift. Our study highlighted that viral receptor-binding avidity and combination of multiple serological assays should be taken into consideration in evaluating and selecting a candidate vaccine virus of H7N9 and other subtypes of influenza viruses.IMPORTANCE The HI assay is a standard method for profiling the antigenic characterization of influenza viruses. Suspected antigenic changes based on HI divergency in H7N9 viruses during the 2016-2017 wave prompted the recommendation of new H7N9 candidate vaccine viruses (CVVs). In this study, we found that the L226Q substitution in HA of A/Guangdong/17SF003/2016 (H7/GD16) increased the viral receptor-binding avidity to red blood cells with no impact on the antigenicity of H7N9 virus. Although immune sera raised by an earlier vaccine strain (H7/AH13) showed poor HI titers against H7/GD16, the H7/AH13 immune sera had potent cross-neutralizing antibody titers against H7/GD16 and could provide complete passive protection against H7N9/GD16 virus challenge in mice. Our study highlights that receptor-binding avidity might lead to biased antigenic evaluation by using the HI assay. Other serological assays, such as the microneutralization (MN) assay, should be considered a complementary indicator for analysis of antigenic variation and selection of influenza CVVs.


Asunto(s)
Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , Glicoproteínas Hemaglutininas del Virus de la Influenza , Subtipo H7N9 del Virus de la Influenza A , Mutación Missense , Infecciones por Orthomyxoviridae , Sustitución de Aminoácidos , Animales , Perros , Femenino , Glicoproteínas Hemaglutininas del Virus de la Influenza/genética , Glicoproteínas Hemaglutininas del Virus de la Influenza/inmunología , Subtipo H7N9 del Virus de la Influenza A/genética , Subtipo H7N9 del Virus de la Influenza A/inmunología , Vacunas contra la Influenza/genética , Vacunas contra la Influenza/inmunología , Macaca mulatta , Células de Riñón Canino Madin Darby , Ratones , Ratones Endogámicos BALB C , Infecciones por Orthomyxoviridae/genética , Infecciones por Orthomyxoviridae/inmunología
5.
Ecotoxicol Environ Saf ; 225: 112719, 2021 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-34478976

RESUMEN

Dissipation of imidacloprid (IMI) and its metabolites (urea, olefin, 5-hydroxy, guanidine, 6-chloronicotinic acid) in Chinese prickly ash (CPA) was investigated using QuEChERS combined with UPLC-MS/MS. Good linearity (r2 ≥0.9963), accuracy (recoveries of 71.8-104.3%), precision (relative standard deviations of 0.9-9.4%), and sensitivity (limit of quantification ≤0.05 mg kg-1) were obtained. After application of IMI at dosage of 467 mg a.i. L-1 for three times with interval of 7 d, the dissipation dynamics of IMI in CPA followed first-order kinetics, with half-life of 6.48-7.29 d. IMI was the main compound in CPA, followed by urea and guanidine with small amounts of olefin, 5-hydroxy, and 6-chloronicotinic acid. The terminal residues of total IMI and its metabolites at PHI of 14-21 d were 0.16-7.80 mg kg-1 in fresh CPA and 0.41-10.44 mg kg-1 in dried CPA, with the median processing factor of 3.62. Risk assessment showed the acute (RQa) and chronic dietary risk quotients (RQc) of IMI in CPA were 0.020-0.083% and 0.052-0.334%, respectively. Based on the dietary structures of different genders and ages of Chinese people, the whole dietary risk assessment indicated that RQc was less than 100% for the general population except for 2- to 7-year-old children (RQc of 109.9%), implying the long-term risks of IMI were acceptable to common consumers except for children.


Asunto(s)
Insecticidas , Residuos de Plaguicidas , Zanthoxylum , Niño , Preescolar , China , Cromatografía Liquida , Humanos , Insecticidas/análisis , Neonicotinoides/análisis , Nitrocompuestos/análisis , Residuos de Plaguicidas/análisis , Medición de Riesgo , Espectrometría de Masas en Tándem
6.
Ecotoxicol Environ Saf ; 228: 112958, 2021 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-34773845

RESUMEN

The present study was carried out to profile the dissipation patterns and residues of five pesticides (triazophos, profenofos, chlorpyrifos, etoxazole and bifenthrin) on kumquat using QuEChERS method coupled with HPLC-MS/MS. The corresponding dietary health risks were also estimated. In the method validation, satisfactory results of good linearity (r2 ≥ 0.9956), sensitivity (limits of quantification ≤0.01 mg/kg), recoveries (71.0-95.7%) with relative standard deviations (0.70-9.4%) were obtained. The half-lives of the five pesticides in kumquat were 13.6-38.5 d under field conditions according to first-order kinetics. Based on the final residue experiment, dietary exposure risks of profenofos, chlorpyrifos, etoxazole and bifenthrin were all acceptably low, with RQc and RQa values of 0.00199-0.122 and 0.00145-0.200, respectively. However, exposure intake of triazophos posed unacceptable acute and chronic health risks for Chinese residents, especially for children with RQa and RQc up to 4.25 and 2.19. Forbidden use suggestion of triazophos and recommended MRLs of profenofos and bifenthrin were put forward in kumquat for safe production and consumption. This work was significant in providing guidance on appropriate application and MRL establishment of pesticides in kumquat.

7.
Scand J Immunol ; 91(1): e12814, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31419843

RESUMEN

Tumour-associated macrophages (TAMs) play an important role in the tumour environment and were reported to be associated with poor prognosis in several tumours. However, the prognostic significance of TAMs in Non-Hodgkin's Lymphoma (NHL) remains controversial. Consequently, we aimed to evaluate the relationship between subpopulations of TAMs and clinical outcomes in NHL patients. We did a comprehensive search of the PubMed, elsevier ScienceDirect, and Cochrane databases and extracted hazard ratio (HR) and their corresponding 95% confidence intervals (95% CIs) from eligible studies. Pooling total effect value by the stata statistical software and analysing correlation of TAMs with overall survival (OS) and progression-free survival (PFS). Furthermore, subgroup analysis and sensitivity analysis were also conducted. We deemed eleven studies, including 1211 NHL patients. Our study demonstrated that high-density CD68+ TAMs are associated with poor OS (HR: 1.17; 95% CI, 0.81-1.54; P = .000) and poor PFS (HR: 1.15; 95% CI, 0.63-1.67; P = .000) compared with low-density CD68+ TAMs in the tumour microenvironment. Similarly, high-density CD163+ TAMs can also predict poor OS (HR: 1.52; 95% CI, 1.11-1.92; P = .000) and shorter PFS (HR: 1.52; 95% CI, 0.73-2.30; P = .000). In addition, the high CD163+ /CD68+ TAMs ratio is significantly correlated with poor OS (HR: 3.59; 95% CI, 0.77-6.40; P = .013). However, in our subgroup analysis, high-density CD68+ TAMs in the tumour microenvironment is associated with better OS (HR: 0.75; 95% CI, 0.41-1.09; P = .000) in NHL patients treated with rituximab chemotherapy. Our results suggest that TAMs are a robust predictor of outcomes in NHL.


Asunto(s)
Linfoma no Hodgkin/etiología , Linfoma no Hodgkin/mortalidad , Macrófagos/inmunología , Microambiente Tumoral/inmunología , Animales , Antígenos CD/metabolismo , Antígenos de Diferenciación Mielomonocítica/metabolismo , Biomarcadores , Recuento de Células , Humanos , Inmunofenotipificación , Linfoma no Hodgkin/metabolismo , Linfoma no Hodgkin/patología , Macrófagos/metabolismo , Macrófagos/patología , Pronóstico , Sesgo de Publicación , Receptores de Superficie Celular/metabolismo
8.
FASEB J ; 33(7): 8241-8248, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30916998

RESUMEN

Type 1 diabetes (T1D) is an autoimmune disease characterized by the immune-mediated destruction of insulin-producing ß cells. Recent studies showed that in addition to malaria, artemisinin and its derivative, artesunate (AS), could alleviate several autoimmune diseases. However, whether AS has a role in the prevention or treatment of T1D is still unknown. Therefore, in this study we administrated AS or DMSO in the drinking water of nonobese diabetic (NOD) mice, a mouse model of T1D. We found that AS administration significantly prevented the incidence of T1D. The frequency of IL-4-producing CD4+ single-positive T cells and CD8+ T cells was significantly elevated, and IFN-γ-producing T cells were reduced in the spleen and pancreatic lymph nodes. In the pancreas, the skewing to IL-4-producing T cells was also observed. In addition, more regulatory T cells were found in the pancreas. mRNA levels of proinflammatory cytokines, including TNF-α and IL-6, were decreased. In addition, AS administration promoted the functional maturity of ß cells in vitro. Our findings demonstrate that AS administration can prevent T1D in NOD mice mainly by reducing autoimmune T cells and increasing protective T cells. Our data constitute the first functional study of AS in T1D, which may provide a new rationale for future translational studies.-Li, Z., Shi, X., Liu, J., Shao, F., Huang, G., Zhou, Z., Zheng, P. Artesunate prevents type 1 diabetes in NOD mice mainly by inducing protective IL-4-producing T cells and regulatory T cells.


Asunto(s)
Artesunato/farmacología , Diabetes Mellitus Experimental/prevención & control , Diabetes Mellitus Tipo 1/prevención & control , Células Secretoras de Insulina/inmunología , Interleucina-4/inmunología , Linfocitos T Reguladores/inmunología , Animales , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/patología , Diabetes Mellitus Experimental/inmunología , Diabetes Mellitus Experimental/patología , Diabetes Mellitus Tipo 1/inmunología , Diabetes Mellitus Tipo 1/patología , Células Secretoras de Insulina/patología , Interferón gamma/inmunología , Interleucina-6/inmunología , Ratones , Ratones Endogámicos NOD , Linfocitos T Reguladores/patología , Factor de Necrosis Tumoral alfa/inmunología
9.
Phys Chem Chem Phys ; 22(16): 9074-9085, 2020 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-32297886

RESUMEN

The intermolecular dynamics in the THz frequency range of the ionic liquids n-butyl-trimethylammonium bis(trifluoromethanesulfonyl)imide, [N1114][NTf2], and methyl-tributylammonium bis(trifluoromethanesulfonyl)imide, [N1444][NTf2], were investigated by a combined usage of inelastic neutron scattering (INS), Raman, and far-infrared (FIR) spectroscopies and the power spectrum calculated by molecular dynamics (MD) simulations. The collective dynamics of the simulated systems is also discussed by the calculation of time correlation functions of charge and mass currents that are projected onto acoustic- and optic-like motions. The INS and Raman measurements have been performed as a function of temperature in the glassy, crystalline, and liquid phases. The excess in the vibrational density of states over the expectation of the Debye theory, the so-called boson peak, is found in the INS and Raman spectra as a peak at ∼2 meV (∼16 cm-1) and also in the direct measurement of heat capacity at very low temperatures (4-20 K). This low-frequency vibration is incorporated into the curve fits of Raman, FIR, and MD data at room temperature. Fits of spectra from these different sources in the range below 100 cm-1 are consistently achieved with three components at ca. 25, 50, and 80 cm-1, but with distinct relative intensities among the different techniques. It is proposed as the collective nature of the lowest-frequency component and the anion-cation intermolecular vibration nature of the highest-frequency component. The MD results indicate that there is no clear distinction between acoustic and optic vibrations in the spectral range investigated in this work for the ionic liquids [N1114][NTf2] and [N1444][NTf2]. The analysis carried out here agrees in part, but not entirely, with other propositions in the literature, mainly from optical Kerr effect (OKE) and FIR spectroscopies, concerning the intermolecular dynamics of ionic liquids.

10.
J Am Chem Soc ; 141(20): 8041-8046, 2019 05 22.
Artículo en Inglés | MEDLINE | ID: mdl-31074276

RESUMEN

The development of models to describe structure and dynamics of nonaqueous electrolyte solutions is challenging, and experimental observations are needed to form a foundation. Here, neutron scattering is used to probe molecular dynamics in nonaqueous organic electrolytes. Two solutions were compared: one contained symmetrical electrolyte molecules prone to crystallize, and one contained desymmetrized electrolyte molecules preferring disordered states. For the latter, calorimetry and neutron data show that a disordered fluid persists to very low temperatures at high concentrations. Upon heating, localized cold crystallization occurs, leading to burst nucleation of microcrystalline solids within fluid phases. Our findings indicate molecular clustering and point to solvation inhomogeneities and molecular crowding in these concentrated fluids.


Asunto(s)
Anisoles/química , Electrólitos/química , Soluciones/química , Tiadiazoles/química , Rastreo Diferencial de Calorimetría , Cristalización , Hidrocarburos Fluorados/química , Imidas/química , Transición de Fase , Dispersión de Radiación , Termodinámica
11.
J Chem Phys ; 150(14): 144506, 2019 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-30981243

RESUMEN

The competition between Coulomb and van der Waals interactions brings forth unique dynamic features and broad applications to ionic liquids. Herein, we present a combined calorimetric, X-ray diffraction, incoherent elastic, and quasi-elastic neutron scattering study, over a wide temperature range (180-340 K), of the relaxational dynamics of the liquid, supercooled liquid, crystalline, glassy, and glacial states of two model ionic liquids: tributylmethylammonium (a good glass-former) and butyltrimethylammonium (a good crystal-former) cations and the bis(trifluoromethanesulfonyl)imide anion. In both systems, we observed two distinct relaxation processes. The Q-dependence of the respective relaxation time shows that the α-process is diffusive, while the ß-process is modulated by the structure of the liquids.

12.
Diabetes Metab Res Rev ; 34(7): e3043, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-29929213

RESUMEN

Type 1 diabetes (T1D) is an autoimmune disease, which is characterized by the destruction of islet ß cells in the pancreas triggered by genetic and environmental factors. In past decades, extensive familial and genome-wide association studies have revealed more than 50 risk loci in the genome. However, genetic susceptibility cannot explain the increased incidence of T1D worldwide, which is very likely attributed by the growing impact of environmental factors, especially gut microbiome. Recently, the role of gut microbiome in the pathogenesis of T1D has been uncovered by the increasing evidence from both human subjects and animal models, strongly indicating that gut microbiome might be a pivotal hub of T1D-triggering factors, especially environmental factors. In this review, we summarize the current aetiological and mechanism studies of gut microbiome in T1D. A better understanding of the role of gut microbiome in T1D may provide us with powerful prognostic and therapeutic tools in the near future.


Asunto(s)
Diabetes Mellitus Tipo 1/inmunología , Diabetes Mellitus Tipo 1/microbiología , Microbioma Gastrointestinal/fisiología , Animales , Diabetes Mellitus Tipo 1/diagnóstico , Diabetes Mellitus Tipo 1/terapia , Susceptibilidad a Enfermedades , Humanos
13.
Regul Toxicol Pharmacol ; 97: 152-162, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29909271

RESUMEN

The presence of pesticide residues in fruit has been of extensive concern worldwide. In this paper, pesticide residues in peach samples in China and their dietary exposure risks for the Chinese general population and children were evaluated. Thirty-nine different pesticides were detected, and 92.3% of samples contained one or more pesticide residues. The most frequently detected pesticide was carbendazim with a detection rate of 60.6%. Residues for eight pesticides in 3.2% of the samples exceeded their MRLs with the highest exceedance of 345%. The results demonstrated that the chronic dietary risks were extremely low for both the general population and children in China. Acute risks from carbendazim, chlorpyrifos, cyhalothrin, cypermethrin, pyridaben and triazophos exposures for children and triazophos for the general population exceeded the acceptable level in the worst case scenario. Only %ARfD of triazophos exceeded 100 when intakes were calculated at the 97.5th percentile of residue level distribution. The risk scoring scheme showed nine pesticides that were considered to pose a higher risk. Different use suggestions for the 39 detected pesticides were proposed to protect the health of consumers. More strictly controlled management of banned pesticides and those suggested for gradually diminished use until banned is highly recommended.


Asunto(s)
Dieta , Contaminación de Alimentos/análisis , Residuos de Plaguicidas/análisis , China , Dieta/efectos adversos , Frutas/química , Humanos , Residuos de Plaguicidas/efectos adversos , Medición de Riesgo , Encuestas y Cuestionarios
14.
Water Sci Technol ; 2017(3): 770-781, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30016295

RESUMEN

A magnetic cation-exchange resin (MCER) was prepared by copolymerization of oleic acid-grafted magnetite with styrene, divinylbenzene (DVB), and triallylisocyanurate (TAIC) for removing Cd(II) from wastewater. A non-magnetic cation-exchange polystyrene resin (CEPR) was also prepared as a reference. Structural and morphological analyses revealed that the MCER and CEPR were mesoporous microspheres; the MCER contained about 25% Fe3O4. The influence of temperature, pH, contact time, and the initial concentration of Cd(II) on the adsorption of Cd(II) was investigated. The maximum adsorption capacity of the MCER reached 88.56 mg/g, which was achieved at 343 K using a Cd(II) initial concentration of 200 mg/L. The adsorption processes attained equilibrium within 120 min for the MCER and 300 min for the CEPR, and were well described by a pseudo-second-order kinetic model. Furthermore, the equilibrium adsorption data fitted the Freundlich isotherm model better than the Langmuir model. The superior magnetic response and regeneration of the MCER make it a good candidate as an adsorbent for removing Cd(II) from wastewater.


Asunto(s)
Cadmio/química , Resinas de Intercambio de Catión/química , Poliestirenos/química , Aguas Residuales/química , Contaminantes Químicos del Agua/química , Adsorción , Cationes/análisis , Óxido Ferrosoférrico , Concentración de Iones de Hidrógeno , Cinética , Temperatura , Purificación del Agua/métodos
15.
Anal Bioanal Chem ; 409(21): 5065-5072, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28664336

RESUMEN

In this study, we have successfully synthesized a forchlorfenuron (CPPU)-imprinted polymer in dimethyl sulfoxide by molecular imprinting technique. In the molecular imprinting, ß-cyclodextrin was used as the monomer with 1,6-hexamethylene diisocyanate (HMDI) as the cross-linking agent that formed a complex with forchlorfenuron by inclusion interactions. The adsorption equilibrium was attained in approximately 30 min and the maximum binding capacity was 26.79 mg/g, which indicated that the adsorption kinetics was relatively fast. The results of adsorption and selectivity experiments have shown that the imprinted polymer was able to bind forchlorfenuron specifically and reversibly. The specific recognition of the imprinted polymer for forchlorfenuron resulted from the cooperative effects of inclusion interaction and hydrophobic interaction. This imprinted polymer was also used to accurately determine forchlorfenuron residue in real fruit samples. In the standard spiked strawberry sample, the adsorption recoveries for forchlorfenuron were as high as 90.3, 84.5, and 90.8%, respectively. The binding specificity of the imprinted polymer for forchlorfenuron resulted from the imprinting effect. Therefore, as a reusable material possessing high affinity and selectivity, the imprinted polymer is promising in application to detect pesticide residues in fruit samples. In addition, because ß-cyclodextrin is water soluble and can include neutral compounds, this molecularly imprinted polymer can be used to recognize pesticides in aqueous solutions. Graphical abstract Schematic demonstration of molecular imprinting and re-binding of forchlorfenuron.


Asunto(s)
Frutas/química , Impresión Molecular/métodos , Compuestos de Fenilurea/análisis , Reguladores del Crecimiento de las Plantas/análisis , Polímeros/química , Piridinas/análisis , beta-Ciclodextrinas/química , Adsorción , Cinética , Límite de Detección , Microscopía Electrónica de Rastreo , Reproducibilidad de los Resultados
16.
Transp Res Part C Emerg Technol ; 76: 132-149, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30220823

RESUMEN

Under the Connected Vehicle environment where vehicles and road-side infrastructure can communicate wirelessly, the Advanced Driver Assistance Systems (ADAS) can be adopted as an actuator for achieving traffic safety and mobility optimization at highway facilities. In this regard, the traffic management centers need to identify the optimal ADAS algorithm parameter set that leads to the optimization of the traffic safety and mobility performance, and broadcast the optimal parameter set wirelessly to individual ADAS-equipped vehicles. Once the ADAS-equipped drivers implement the optimal parameter set, they become active agents that work cooperatively to prevent traffic conflicts, and suppress the development of traffic oscillations into heavy traffic jams. Measuring systematic effectiveness of this traffic management requires am analytic capability to capture the quantified impact of the ADAS on individual drivers' behaviors and the aggregated traffic safety and mobility improvement due to such an impact. To this end, this research proposes a synthetic methodology that incorporates the ADAS-affected driving behavior modeling and state-of-the-art microscopic traffic flow modeling into a virtually simulated environment. Building on such an environment, the optimal ADAS algorithm parameter set is identified through a multi-objective optimization approach that uses the Genetic Algorithm. The developed methodology is tested at a freeway facility under low, medium and high ADAS market penetration rate scenarios. The case study reveals that fine-tuning the ADAS algorithm parameter can significantly improve the throughput and reduce the traffic delay and conflicts at the study site in the medium and high penetration scenarios. In these scenarios, the ADAS algorithm parameter optimization is necessary. Otherwise the ADAS will intensify the behavior heterogeneity among drivers, resulting in little traffic safety improvement and negative mobility impact. In the high penetration rate scenario, the identified optimal ADAS algorithm parameter set can be used to support different control objectives (e.g., safety improvement has priority vs. mobility improvement has priority).

17.
New Phytol ; 206(3): 1101-1115, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25644034

RESUMEN

Aphids are important pests of wheat (Triticum aestivum) that affect crop production globally. Herbivore-induced emission of sesquiterpenes can repel pests, and farnesyl pyrophosphate synthase (FPS) is a key enzyme involved in sesquiterpene biosynthesis. However, fps orthologues in wheat and their functional roles in sesquiterpene synthesis and defence against aphid infestation are unknown. Here, two fps isoforms, Tafps1 and Tafps2, were identified in wheat. Quantitative real-time polymerase chain reaction (qRT-PCR) and in vitro catalytic activity analyses were conducted to investigate expression patterns and activity. Heterologous expression of these isoforms in Arabidopsis thaliana, virus-induced gene silencing (VIGS) in wheat and aphid behavioural assays were performed to understand the functional roles of these two isoforms. We demonstrated that Tafps1 and Tafps2 played different roles in induced responses to aphid infestation and in sesquiterpene synthesis. Heterologous expression in A. thaliana resulted in repulsion of the peach aphid (Myzus persicae). Wheat plants with these two isoforms transiently silenced were significantly attractive to grain aphid (Sitobion avenae). Our results provide new insights into induced defence against aphid herbivory in wheat, in particular, the different roles of the two Tafps isoforms in both sesquiterpene biosynthesis and defence against aphid infestation.


Asunto(s)
Áfidos/fisiología , Geraniltranstransferasa/química , Sesquiterpenos/metabolismo , Triticum/enzimología , Secuencia de Aminoácidos , Animales , Arabidopsis/genética , Arabidopsis/metabolismo , Silenciador del Gen , Geraniltranstransferasa/genética , Herbivoria , Interacciones Huésped-Parásitos/genética , Isoenzimas/química , Isoenzimas/genética , Datos de Secuencia Molecular , Plantas Modificadas Genéticamente/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa , Alineación de Secuencia , Análisis de Secuencia de Proteína , Triticum/genética
18.
J Sci Food Agric ; 95(10): 2047-52, 2015 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-25242114

RESUMEN

BACKGROUND: To understand the effect of low-molecular-weight (LMW) glutenin alleles at the Glu-A3 locus on sodium dodecyl sulfate (SDS) sedimentation volume and solvent retention capacity (SRC) values, 244 accessions of Chinese wheat (Triticum aestivum L.) mini core collections were investigated. In this study the significant differences in wholemeal flour SDS sedimentation volume and SRC values associated with specific glutenin alleles at the Glu-A3 locus were explained. RESULTS: Seven glutenin alleles at the Glu-A3 locus were confirmed by locus-specific polymerase chain reaction (PCR). SDS sedimentation volume and lactic acid SRC value were significantly affected by alleles Glu-A3b and Glu-A3g. Based on total average values, 28 varieties carrying Glu-A3b had significantly higher means of SDS sedimentation volume and lactic acid SRC value, whereas 19 varieties carrying Glu-A3g had significantly lower means. Alleles Glu-A3d and Glu-A3f significantly increased only SDS sedimentation volume and sucrose SRC value respectively. Correlation analysis showed that SDS sedimentation volume was uncorrelated with lactic acid SRC and sucrose SRC values. CONCLUSION: The Glu-A3 LMW glutenin subunit could predict 12.8% of the variance in SDS sedimentation volume, 4.7% in lactic acid SRC and 6.4% in sucrose SRC.


Asunto(s)
Regulación de la Expresión Génica de las Plantas/fisiología , Glútenes/química , Glútenes/genética , Dodecil Sulfato de Sodio/química , Triticum/metabolismo , Alelos , Harina/análisis , Análisis de los Alimentos , Genotipo , Glútenes/metabolismo , Solventes , Triticum/genética
19.
Zhongguo Zhong Yao Za Zhi ; 40(2): 339-45, 2015 Jan.
Artículo en Zh | MEDLINE | ID: mdl-26080570

RESUMEN

A systematic review was undertaken, including studies that evaluated the incidence of the blood system adverse events of Tripterygium wilfordii (TWP). Medline, Embase and the Cochrane library were searched for relevant studies, including RCT, cohort studies and case series, of patients treated with TWP published in English and Chinese from inception up until May 25th, 2013 with the keywords including "Tripterygium wilfordii", "toxicity", "reproductive", "side effect", "adverse", "safety" and "tolerability". Relevant information was extracted and the incidence of the blood system adverse events was pooled with MetaAnalyst software. Besides, subgroup and sensitivity analyses were performed based on age, mode of medicine, observation time and disease system. According to inclusion and exclusion criteria, a total of 49 articles were included in the meta-analysis, they were split into 54 researches incorporated in the analysis. There is a large degree of heterogeneity among the studies, so data was analyzed using random-effects model and the summary estimates of incidence of the blood system adverse events was 6.1%. The weighted combined incidence of three major blood system adverse events were white-blood cells decreasing 5.6% (95% CI, 4.3% - 7.3%), hemoglobin decreasing 1.7% (95% CI, 0.5% - 5.0%) and platelet decreasing 1.8% (95% CI, 1.0% - 3.1%), respectively . Sensitivity analyses based on 45 studies with high quality showed the combined value was close to the summary estimate of total 54 studies. The current evidence indicates that the incidence of the blood system adverse events induced by TWP was high; attentions should be paid on to the prevention and treatment of the blood system adverse events.


Asunto(s)
Células Sanguíneas/efectos de los fármacos , Tripterygium/efectos adversos , Hemoglobinas/análisis , Humanos
20.
J Mater Sci Mater Med ; 25(2): 453-9, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24186151

RESUMEN

Bone cement containing alumina particles with a specific crystalline structure exhibits the ability to bond with bone. These particles (AL-P) are mainly composed of delta-type alumina (δ-Al2O3). It is likely that some of the proteins present in the body environment are adsorbed onto the cement and influence the expression of its bioactivity. However, the effect that this adsorption of proteins has on the bone-bonding mechanism of bone cement has not yet been elucidated. In this study, we investigated the characteristics of the adsorption of bovine serum albumin (BSA) onto AL-P and compared them with those of its adsorption onto hydroxyapatite (HA), which also exhibits bone-bonding ability, as well as with those of adsorption onto alpha-type alumina (α-Al2O3), which does not bond with bone. The adsorption characteristics of BSA onto AL-P were very different from those onto α-Al2O3 but quite similar to those onto HA. It is speculated that BSA is adsorbed onto AL-P and HA by interionic interactions, while it is adsorbed onto α-Al2O3 by electrostatic attraction. The results suggest that the specific adsorption of albumin onto implant materials might play a role in the expression of the bone-bonding abilities of the materials.


Asunto(s)
Óxido de Aluminio/química , Albúmina Sérica Bovina/química , Adsorción , Cristalización , Electroforesis en Gel de Poliacrilamida , Microscopía Electrónica de Rastreo , Estructura Molecular , Proteolisis
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