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1.
Ecotoxicol Environ Saf ; 265: 115511, 2023 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-37774542

RESUMEN

Glyphosate is an herbicide extensively used worldwide that can remain in the soil. Phytoremediation to decontaminate polluted water or soil requires a plant that can accumulate the target compound. Vulpia myuros is an annual fescue that can be used as a heavy mental phytoremediation strategy. Recently, it has been used to intercrop with tea plant to prohibit the germination and growth of other weeds in tea garden. In order to know whether it can be used an decontaminating glyphosate' plant in water or soil, in this study, glyphosate degradation behavior was investigated in Vulpia myuros cultivated in a hydroponic system. The results showed that the concentration of glyphosate in the nutrient solution decreased from 43.09 µg mL-1 to 0.45 µg mL-1 in 30 days and that 99% of the glyphosate molecules were absorbed by V. myuros. The contents of glyphosate in the roots reached the maximum (224.33 mg kg-1) on day 1 and then decreased. After 3 days, the content of glyphosate in the leaves reached the highest value (215.64 mg kg-1), while it decreased to 156.26 mg kg-1 in the roots. The dissipation dynamics of glyphosate in the whole hydroponic system fits the first-order kinetic model C = 455.76e-0.21 t, with a half-life of 5.08 days. Over 30 days, 80% of the glyphosate was degraded. The contents of the glyphosate metabolite amino methyl phosphoric acid (AMPA), ranged from 0.103 mg kg-1 on day 1-0.098 mg kg-1 on day 30, not changing significantly over time. The Croot/solution, Cleaf/solution and Cleaf/root were used to express the absorption, transfer, and distribution of glyphosate in V. myuros. These results indicated that glyphosate entered into the root system through free diffusion, which was influenced by both the log Kow and the concentration of glyphosate in the nutrient solution, and that glyphosate was either easily transferred to the leaves through the transpiration stream, accumulated, or degraded. The degradation of glyphosate in V. myuros indicated that it has potential as a remediating plant for environmental restoration.


Asunto(s)
Festuca , Herbicidas , Contaminantes del Suelo , Contaminantes del Suelo/análisis , Biodegradación Ambiental , Festuca/metabolismo , Suelo , Herbicidas/análisis , Agua , , Glifosato
2.
Anal Chem ; 94(21): 7528-7535, 2022 05 31.
Artículo en Inglés | MEDLINE | ID: mdl-35581026

RESUMEN

High-throughput surface-enhanced Raman scattering (SERS) reader, especially for liquid sample testing, is of great significance and huge demand in biology, environment, and other analytical fields. Inspired by the principle of microplate reader, herein, we developed a microplate-SERS reader for semiautomatic and high-throughput assays by virtue of three-dimensional liquid interfacial arrays (LIAs). For the first time, the formation of LIA in oil-in-water state, water-in-oil state, and two-dimensional plane state is realized by operating the hydrophilicity (contact angle) of the container. Through the force analysis of LIA, the effect of organic (O) phase density on the relative position of LIA was quantified. In addition, the optimized reader offers fast and continuous semiautomatic detection of 12 samples below 10 min with great signal reproducibility (calibration with the characteristic peak of O phase as the internal standard). The isolated wells in the microplate prevent analyte cross talk, allowing accurate quantification of each sample. Multiplex analysis capability highlights that this reader has the ability of rapid identification and quantification of samples containing various analytes and concentrations. The results demonstrate high-resolution dual and triple analyte detection with fully preserved signal and Raman features of individual analytes in a mixture, which implies that it also has excellent anticounterfeiting applications. This microplate-SERS reader combines the superior advantages of the LIA, microplate, and SERS techniques to retrieve the molecular vibrational fingerprints of various chemicals in complex media.


Asunto(s)
Espectrometría Raman , Agua , Interacciones Hidrofóbicas e Hidrofílicas , Reproducibilidad de los Resultados , Espectrometría Raman/métodos
3.
Food Chem ; 370: 130846, 2022 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-34536785

RESUMEN

Ensuring the safety of tea requires effective methods for the simultaneous analysis of pesticide residues in the product. A sensitive and reliable method to scan for 134 pesticide residues in tea was developed that employs a novel Multi-Functional Filter (MFF) based on d-SPE extraction and ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry. The adsorption material was developed by porous polyvinylpolypyrrolidone (PVPP) for the removal of polyphenols. Acetonitrile extraction was passed through a syringe and then detected by UPLC-Q-TOF-MS. Method validation revealed satisfactory linearity with correlation coefficients higher than 0.985 for all pesticides. All limits of quantification were below 10 µg/kg. The matrix effects of 133 of the pesticides were nearly negligible (<20%), except for Sebutylazine (=22%). The recoveries at two spiked levels (50, 100 µg/kg) were 66.83-118.33%, and the Relative standard deviation (RSD) was lower than 20%, indicating accuracy and precision of the new method.


Asunto(s)
Residuos de Plaguicidas , Plaguicidas , Cromatografía Líquida de Alta Presión , Contaminación de Alimentos/análisis , Espectrometría de Masas , Residuos de Plaguicidas/análisis , Extracción en Fase Sólida ,
4.
J Int Med Res ; 49(10): 3000605211053557, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34686095

RESUMEN

A chondroma is a common benign cartilaginous tumor. However, a primary soft tissue chondroma of the posterior mediastinum is very rare. We herein report a case involving a 51-year-old man with a posterior mediastinal mass. The mass was dissected by thoracoscopy through the eighth intercostal space. Pathological examination led to a definitive diagnosis of a primary mediastinal chondroma with no criteria of malignancy. Preoperative diagnosis of a posterior mediastinal soft tissue chondroma is not easy because of its rarity and lack of typical features other than calcification. When a posterior mediastinal well-circumscribed soft tissue mass contains calcification and shows no obvious enhancement, the possibility of a soft tissue chondroma should be considered.


Asunto(s)
Condroma , Neoplasias del Mediastino , Neoplasias de Tejido Conjuntivo , Neoplasias de los Tejidos Blandos , Condroma/diagnóstico por imagen , Condroma/cirugía , Humanos , Masculino , Neoplasias del Mediastino/diagnóstico por imagen , Neoplasias del Mediastino/cirugía , Mediastino , Persona de Mediana Edad , Neoplasias de los Tejidos Blandos/diagnóstico por imagen , Neoplasias de los Tejidos Blandos/cirugía
5.
BMC Plant Biol ; 21(1): 337, 2021 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-34271878

RESUMEN

BACKGROUND: Pesticide residue and its poor utilization remains problematic in agricultural development. To address the issue, a nano-pesticide has been developed by incorporating pesticide acetamiprid in porous silica nanoparticles. RESULTS: This nano-pesticide had an acetamiprid loading content of 354.01 mg g-1. Testing LC50 value against tea aphids of the commercial preparation was three times that of the nano-pesticide. In tea seedlings (Camellia sinensis L.), acetamiprid was transported upward from the stem to the young leaves. On day 30, the average retained concentrations in tea leaves treated with the commercial preparation were about 1.3 times of that in the nano-pesticide preparation. The residual concentrations of dimethyl-acetamiprid in leaves for plants treated with the commercial preparation were about 1.1 times of that in the nano-pesticide preparation. Untargeted metabolomics of by LC-MS on the young leaves of tea seedlings under nano-pesticide and commercial pesticide treatments showed significant numbers of differentially expressed metabolites (P < 0.05 and VIP > 1). Between the nano-pesticide treatment group and the commercial preparation treatment group there were 196 differentially expressed metabolites 2 h after treatment, 200 (7th day), 207 (21st day), and 201 (30th day) in negative ion mode, and 294 (2nd h), 356 (7th day), and 286 (30th day) in positive ion mode. Preliminary identification showed that the major differentially expressed metabolites were glutamic acid, salicylic acid, p-coumaric acid, ribonic acid, glutamine, naringenin diglucoside, sanguiin H4, PG (34:2) and epiafzelechin. CONCLUSIONS: This work demonstrated that our nano-pesticide outperformed the conventional pesticide acetamiprid in terms of insecticidal activity and pesticide residue, and the absorption, transportation and metabolism of nano-pesticide in tea plant were different, which pave a new pathway for pest control in agricultural sector.


Asunto(s)
Camellia sinensis/metabolismo , Insecticidas , Nanopartículas , Neonicotinoides , Hojas de la Planta/metabolismo , Neonicotinoides/metabolismo , Residuos de Plaguicidas
6.
J Agric Food Chem ; 69(28): 7969-7978, 2021 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-34232658

RESUMEN

The tea shrub is grown in long-standing orchards, an environment that is suitable for persistent weed growth, which is increasingly controlled by herbicides. Therefore, there is increasing concern that tea consumers may be exposed to herbicide residues. In this study, the levels of glufosinate-ammonium (GLU), glyphosate [N-(phosphonomethyl) glycine; PMG], and its metabolite aminomethyl phosphoric acid (AMPA) were determined in tea samples by HPLC-MS/MS using several current purification methods and a new method that we developed herein. The matrix effect of our proposed method was between -27.3 and 27.7%, which was lower than that in other methods, indicating that this method effectively reduced the interference of tea matrix in the mass spectrometry process. This method was used to determine the levels of PMG, GLU, and AMPA in 780 samples, including six traditional Chinese teas (green tea, black tea, oolong tea, dark tea, white tea, and yellow tea) and a floral tea, from 14 provinces of China. Probability estimates showed that the 95th percentile risk entropy values of the three pesticide residues were far below the acceptable risk level. The risk assessment results showed that exposure to PMG, GLU, and AMPA caused by drinking tea beverages poses no significant risk to human health.


Asunto(s)
Herbicidas , Espectrometría de Masas en Tándem , Aminobutiratos , China , Cromatografía Líquida de Alta Presión , Glicina/análogos & derivados , Herbicidas/análisis , Humanos , Ácidos Fosfóricos , Medición de Riesgo , , Glifosato
7.
Sensors (Basel) ; 21(5)2021 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-33668245

RESUMEN

Automatic modulation recognition (AMR) is a significant technology in noncooperative wireless communication systems. This paper proposes a deep complex network that cascades the bidirectional long short-term memory network (DCN-BiLSTM) for AMR. In view of the fact that the convolution operation of the traditional convolutional neural network (CNN) loses the partial phase information of the modulated signal, resulting in low recognition accuracy, we first apply a deep complex network (DCN) to extract the features of the modulated signal containing phase and amplitude information. Then, we cascade bidirectional long short-term memory (BiLSTM) layers to build a bidirectional long short-term memory model according to the extracted features. The BiLSTM layers can extract the contextual information of signals well and address the long-term dependence problems. Next, we feed the features into a fully connected layer. Finally, a softmax classifier is used to perform classification. Simulation experiments show that the performance of our proposed algorithm is better than that of other neural network recognition algorithms. When the signal-to-noise ratio (SNR) exceeds 4 dB, our model's recognition rate for the 11 modulation signals can reach 90%.

8.
Food Chem ; 344: 128579, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33199115

RESUMEN

The absorption, distribution, metabolism and primary risk evaluation data of four neonicotinoids and two organophosphate insecticides in tea plant (Camellia sinensis L.) were compared. 22 neonicotinoid metabolites and 2 organophosphate metabolites were identified. The amount ratio of each neonicotinoid metabolite to its corresponding parent (M/P) was lower than 0.076 in the treated time. The organophosphates (omethoate and methamidophos) increased sharply, with M/Ps as high as 1.111 and 0.612. The risks evaluation of insecticides and their metabolites in treated leaves on day seven showed that the chronic risk was from the lowest 0.0759 (clothianidin) to highest 43.6409% (dimethoate), and the acute risk was highest 0.0370 for all targets. The calculated combined toxicity of leaves treated with acephate reached 1.5 folds in mature, 1.5 folds in tender leaves than no metabolites, and which of dimethoate were 2.1 folds in mature and 3.7 folds in tender leaves.


Asunto(s)
Camellia sinensis/química , Insecticidas/análisis , Neonicotinoides/análisis , Organofosfatos/análisis , Camellia sinensis/metabolismo , Cromatografía Líquida de Alta Presión , Humanos , Insecticidas/metabolismo , Neonicotinoides/química , Neonicotinoides/metabolismo , Nitrocompuestos/química , Nitrocompuestos/metabolismo , Organofosfatos/metabolismo , Hojas de la Planta/química , Hojas de la Planta/metabolismo , Raíces de Plantas/química , Raíces de Plantas/metabolismo , Tallos de la Planta/química , Tallos de la Planta/metabolismo , Riesgo , Espectrometría de Masas en Tándem , Tiametoxam/análisis , Tiametoxam/metabolismo
9.
Int J Mol Med ; 46(5): 1743-1754, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33000222

RESUMEN

Long non­coding RNAs (lncRNAs) have recently gained attention due to their important roles in human cancer types, such as breast and gastric cancer. The present study measured alterations in muskelin 1 antisense RNA (MKLN1­AS) expression in hepatocellular carcinoma (HCC) and evaluated its clinical value in patients with HCC. Additionally, the current study investigated the effects of MKLN1­AS on the malignant features of HCC cells. The detailed molecular mechanisms underlying the cancer­promoting activities of MKLN1­AS in HCC cells were also elucidated. MKLN1­AS expression in HCC tissues and cell lines was detected using reverse­transcription quantitative PCR (RT­qPCR). Cell Counting Kit­8 assays and flow cytometry were used to determine the roles of MKLN1­AS in HCC cell proliferation and apoptosis. Migration and invasion assays, as well as tumor xenograft experiments were conducted to analyze migration and invasion in vitro and tumor growth in vivo, respectively. The interaction among microRNA­654­3p (miR­654­3p), MKLN1­AS and hepatoma­derived growth factor (HDGF) in HCC was investigated using luciferase reporter assay, RNA immunoprecipitation assay, RT­qPCR, western blotting and rescue experiments. MKLN1­AS was upregulated in HCC tissues and cell lines, and a high MKLN1­AS expression was associated with shorter overall survival and disease­free survival in patients with HCC. Functionally, the knockdown of MKLN1­AS impaired HCC cell proliferation, migration and invasion, as well as induced cell apoptosis in vitro. Knockdown of MKLN1­AS expression also inhibited cell proliferation in vivo. The results indicated that MKLN1­AS functioned as a competing endogenous RNA by sponging miR­654­3p in HCC cells. Additionally, miR­654­3p targeting of HDGF was positively modulated by MKLN1­AS, and miR­654­3p knockdown partially abrogated this effect. Rescue experiments demonstrated that knockdown of miR­654­3p and overexpression of HDGF both abolished MKLN1­AS knockdown­induced cellular processes in HCC. In summary, MKLN1­AS induced pro­oncogenic effects during HCC progression by serving as a molecular sponge for miR­654­3p to increase HDGF expression. Therefore, the MKLN1­AS/miR­654­3p/HDGF axis may offer a novel target for the diagnosis, prognosis, prevention and treatment of HCC.


Asunto(s)
Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patología , Progresión de la Enfermedad , Péptidos y Proteínas de Señalización Intercelular/genética , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patología , MicroARNs/metabolismo , ARN Largo no Codificante/metabolismo , Animales , Apoptosis/genética , Secuencia de Bases , Carcinogénesis/genética , Carcinogénesis/patología , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , Regulación Neoplásica de la Expresión Génica , Técnicas de Silenciamiento del Gen , Humanos , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Masculino , Ratones Endogámicos BALB C , Ratones Desnudos , MicroARNs/genética , Invasividad Neoplásica , Pronóstico , ARN Largo no Codificante/genética , Regulación hacia Arriba/genética
10.
J Sci Food Agric ; 100(13): 4921-4929, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32472940

RESUMEN

BACKGROUND: The use of pesticides during tea plant cultivation helps agricultural production and prevents and controls pests, diseases and weeds. It is of the utmost importance to balance pesticide application with tea quality, safety and consumer health. The uptake of pesticides into plants may lead to the presence of residues that are hazardous to human health, especially for some foliar-applied insecticides. The movability or penetration behavior of a pesticide remains unknown after it has been sprayed on a tea leaf. RESULTS: Two organophosphate (acephate, trichlorfon) and three neonicotinoid pesticides (imidacloprid, thiamethoxam and acetamiprid) were confirmed with respect to their removal from the treated fresh leaves of tea saplings via washing in a phytotron. Four of the targets have little penetrative ability into tea leaves, mainly existing (> 92%) on the tea leaf surface, except for trichlorfon (> 70%), for 30 days. With higher vapor pressures, trichlorfon and acetamiprid had relatively higher penetration ratios of 8.63-29.60% and 0.28-8.03% respectively. Two organophosphate insecticides were found to degrade more quickly, with lower final amounts of residues on and in the whole leaf compared to the neonicotinoid pesticides. In a field test, these residues could be reduced by 45-72% after a pre-harvest interval of 3 days, and by 16-89% after 7 days, when the fresh tea shoots were sprayed with 2 or 4 L m-2 water. CONCLUSION: Pesticides with different structures have different penetration abilities on the tea leaf surface, and some pesticides in commercial tea can be reduced by spraying with water before fresh leaves are picked. © 2020 Society of Chemical Industry.


Asunto(s)
Riego Agrícola/métodos , Insecticidas/análisis , Residuos de Plaguicidas/análisis , Hojas de la Planta/química , Camellia sinensis/química , Contaminación de Alimentos/análisis , Neonicotinoides/análisis , Nitrocompuestos/análisis , Té/química , Tiametoxam/análisis , Agua/análisis
11.
Food Chem ; 308: 125648, 2020 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-31670191

RESUMEN

The tenderness of the fresh tea leaves can affect the quality of tea products. It is important to develop a mechanized, accurate way to evaluate the quality of fresh leaves that avoids the uncertainty of a subjective evaluation. Herein, an in-situ, ultra-rapid Raman microscopy strategy to quantify carotenoids in tea leaves was established. The Raman microscopy of carotenoids distribution in leaves from new branches of 22 representative tea varieties showed that the average carotenoid signals increased from a low level in the bud to a high level in the fourth leaf, which represent different developmental stages. The concentration of carotenoids in the bud to fourth leaf, which were from 69.1 ng mg-1 to 199.5 ng mg-1, respectively. These results demonstrate that Raman imaging can serve as an in-situ, non-destructive and ultra-rapid technology for determining the tenderness of fresh tea leaves and be used in quality control for tea processing.


Asunto(s)
Carotenoides/análisis , Espectrometría Raman/métodos , Té/química , Hojas de la Planta/química , Factores de Tiempo
12.
J Agric Food Chem ; 67(19): 5384-5393, 2019 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-30350971

RESUMEN

Rinsing dried tea leaves before brewing is a traditional way of preparing rolled oolong tea in China. This study analyzes how rinsing green, black, and oolong tea before brewing affects the levels of pesticide residues in the tea infusion. Eight representative insecticides of different polarities were tracked, namely, three neonicotinoids (acetamiprid, imidacloprid, and thiamethoxam), two organophosphates (dimethoate and malathion), and three pyrethroids (bifenthrin, ß-cypermethrin, and fenvalerate). The results showed that the eight pesticides transferred into the rinse water at rates between 0.2 and 24% after 5, 10, 20, or 30 s. Rinsing tea before brewing reduced the pesticide risk levels by 5-59% in the tea infusion. Five functional components, such as epigallocatechin gallate and caffeine, were reduced by 0-11% in the tea infusion. The results can be used to develop an effective method of rinsing tea before brewing that reduces pesticide exposure risks.


Asunto(s)
Camellia sinensis/química , Manipulación de Alimentos/métodos , Residuos de Plaguicidas/análisis , China , Contaminación de Alimentos/análisis , Hojas de la Planta/química , Té/química
13.
Food Chem ; 237: 305-311, 2017 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-28764001

RESUMEN

To investigate the degradation and penetration behaviors of the organophosphate insecticide dimethoate applied on spinach leaves, in situ SERS and LC-MS methods were used to detect dimethoate residue on&in spinach leaves picked on different days after treatment (DAT). The SERS and LC-MS methods determined that the dimethoate degradation rate followed first-order kinetics, with a half-life of 3.56 or 4.13days, depending on the respective method. The correlation coefficient of quantification value of these two methods was 0.9562. With the SERS method, we detected most of the penetrated dimethoate in the depth of 60-110µm. With the LC-MS method, we detected dimethoate up to 0.17ng in leaves and that the dimethoate on:in ratio of spinach leaves ranged from 562.25 on 0 DAT to 5.23 on 14 DAT. The combination of these two methods facilitated a better understanding of the behavior and biological fate of pesticides in a complex biological system.


Asunto(s)
Spinacia oleracea/química , Cromatografía Liquida , Dimetoato , Espectrometría de Masas , Plaguicidas
14.
J Agric Food Chem ; 65(35): 7638-7646, 2017 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-28795804

RESUMEN

The uptake, translocation, metabolism, and distribution behavior of glyphosate in nontarget tea plant were investigated. The negative effects appeared to grown tea saplings when the nutrient solution contained glyphosate above 200 mg L-1. Glyphosate was highest in the roots of the tea plant, where it was also metabolized to aminomethyl phosphonic acid (AMPA). The glyphosate and AMPA in the roots were transported through the xylem or phloem to the stems and leaves. The amount of AMPA in the entire tea plant was less than 6.0% of the amount of glyphosate. The glyphosate level in fresh tea shoots was less than that in mature leaves at each day. These results indicated that free glyphosate in the soil can be continuously absorbed by, metabolized in, and transported from the roots of the tea tree into edible leaves, and therefore, free glyphosate residues in the soil should be controlled to produce teas free of glyphosate.


Asunto(s)
Camellia sinensis/metabolismo , Glicina/análogos & derivados , Herbicidas/metabolismo , Contaminantes del Suelo/metabolismo , Transporte Biológico , Camellia sinensis/química , Camellia sinensis/crecimiento & desarrollo , Glicina/análisis , Glicina/metabolismo , Herbicidas/análisis , Floema/química , Floema/metabolismo , Hojas de la Planta/química , Hojas de la Planta/metabolismo , Raíces de Plantas/química , Raíces de Plantas/metabolismo , Contaminantes del Suelo/análisis , Glifosato
15.
J Virol Methods ; 202: 87-94, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24642240

RESUMEN

In vitro studies related to various viral pathogenesis in swine have been hampered by the lack of relevant porcine cell lines. The susceptibility to porcine rotavirus infection was evaluated by using a newly established porcine intestinal epithelial cell line. Immunohistochemical staining for cytokeratin confirmed that the cultured cells were epithelial cells. Measurement of cell viability and detection of infected cells confirmed that these epithelial cells were susceptible to porcine rotavirus infection. This study describes the cytopathic changes in cultured porcine intestinal epithelial cells during virus invasion. Following infection with porcine rotavirus, the cell cultures contained viral protein at 16 h post-infection as detected by direct immunofluorescence. The epithelial cell cultures provided competent target cells for studying host cell responses to porcine rotavirus and a homologous system for investigating the response of intestinal epithelial cells during viral infection.


Asunto(s)
Células Epiteliales/virología , Rotavirus/crecimiento & desarrollo , Animales , Línea Celular , Supervivencia Celular , Células Epiteliales/química , Inmunohistoquímica , Queratinas/análisis , Porcinos , Cultivo de Virus/métodos
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