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1.
Biomed Chromatogr ; 38(2): e5779, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38050189

RESUMO

To clarify the residue behavior and possible dietary risk of abamectin in fresh corn, bitter melon, and Fritillaria, a method was developed for the simultaneous determination of abamectin residues in fresh corn, bitter melon, and Fritillaria by QuEChERS (quick, easy, cheap, effective, rugged, safe) ultra-performance liquid chromatography-tandem mass spectrometry. The mean recovery of abamectin in fresh corn, bitter melon, and Fritillaria was 86.48%-107.80%, and the relative standard deviation was 2.07%-10.12%. The detection rates of abamectin residues in fresh corn, bitter melon, and Fritillaria were 62.50%, 87.50%, and 80.00%, respectively. The residues of abamectin in fresh corn, bitter melon, and Fritillaria were not more than 0.020, 0.019, and 0.087 mg/kg, respectively. Based on these results, dietary risk assessment showed that the risk content of abamectin residues in long- and short-term dietary exposure for Chinese consumers was 61.57% and 0.41%-1.11%, respectively, indicating that abamectin in fresh corn, bitter melon, and Fritillaria in the market would not pose a significant risk to consumers.


Assuntos
Fritillaria , Ivermectina/análogos & derivados , Momordica charantia , Resíduos de Praguicidas , Momordica charantia/química , Zea mays , Medição de Risco , Resíduos de Praguicidas/análise
2.
J Environ Sci Health B ; 59(4): 152-159, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38347689

RESUMO

Picoxystrobin is a systemic fungicide widely used on potato, citrus fruit, and Dendrobium officinale. To provide information for the risk assessment of potato, citrus, and Dendrobium officinale, field experiments combined with QuEChERS and HPLC-MS/MS were performed to detect picoxystrobin. Picoxystrobin had good linearity (R2 > 0.99), the average recovery rate was 75 - 102%, and the relative standard deviation was 1 - 11%. Picoxystrobin was utilized as the test agent in field experiments, and samples were evaluated and analyzed at various times after the final application utilizing random sampling. The results showed that picoxystrobin residuals in potato and citrus (orange meat) were ˂ 0.01 mg kg-1, whereas those in citrus whole fruit, D. officinale (fresh), and D. officinale (dried) were < 0.05 - 0.084, 0.16 - 3.82, and 0.34 - 9.05 mg kg-1, respectively. Based on these results, both the acute risk quotient (2.77%) and chronic risk quotient (8.7%) were ˂100%, and the dietary risk assessment indicated that the intake of picoxystrobin residues in potato, citrus fruit, and D. officinale did not pose a health risk. This study can guide the reasonable use of picoxystrobin in potato, citrus fruit, and D. officinale.


Assuntos
Citrus , Dendrobium , Solanum tuberosum , Estrobilurinas , Espectrometria de Massas em Tandem/métodos , Medição de Risco
3.
Brief Bioinform ; 22(6)2021 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-34160582

RESUMO

Elucidation of cell subpopulations at high resolution is a key and challenging goal of single-cell ribonucleic acid (RNA) sequencing (scRNA-seq) data analysis. Although unsupervised clustering methods have been proposed for de novo identification of cell populations, their performance and robustness suffer from the high variability, low capture efficiency and high dropout rates which are characteristic of scRNA-seq experiments. Here, we present a novel unsupervised method for Single-cell Clustering by Enhancing Network Affinity (SCENA), which mainly employed three strategies: selecting multiple gene sets, enhancing local affinity among cells and clustering of consensus matrices. Large-scale validations on 13 real scRNA-seq datasets show that SCENA has high accuracy in detecting cell populations and is robust against dropout noise. When we applied SCENA to large-scale scRNA-seq data of mouse brain cells, known cell types were successfully detected, and novel cell types of interneurons were identified with differential expression of gamma-aminobutyric acid receptor subunits and transporters. SCENA is equipped with CPU + GPU (Central Processing Units + Graphics Processing Units) heterogeneous parallel computing to achieve high running speed. The high performance and running speed of SCENA combine into a new and efficient platform for biological discoveries in clustering analysis of large and diverse scRNA-seq datasets.


Assuntos
Algoritmos , Análise por Conglomerados , Biologia Computacional/métodos , RNA-Seq , Análise de Célula Única/métodos , Bases de Dados Genéticas , Reprodutibilidade dos Testes , Navegador
4.
Cell Commun Signal ; 21(1): 121, 2023 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-37231451

RESUMO

BACKGROUND: It is well-established that most Hepatocellular carcinoma (HCC) patients die of metastasis, yet the potential mechanisms orchestrating metastasis remain poorly understood. Current evidence suggests that the dysregulation of METTL3-mediated m6A methylation modification is closely associated with cancer progression. STAT3 is an oncogenic transcription factor that reportedly plays a central role in the occurrence and development of HCC. However, the relationship between METTL3 and STAT3 in HCC metastasis remains unclear. METHODS: The relationship between METTL3 expression and the survival of HCC patients was assessed by online tools GEPIA and Kaplan-Meier Plotter. Western blotting, Tissue microarray (TMA), and immunohistochemistry (IHC) staining were used to evaluate the expression levels of METTL3 and STAT3 in HCC cell lines and metastatic and non-metastatic tissues. Methylated RNA immunoprecipitation (MeRIP), MeRIP sequencing (MeRIP-seq), qRT-PCR, RNA immunoprecipitation (RIP), Western blotting and luciferase reporter gene assay were utilized to clarify the mechanism of METTL3 regulating STAT3 expression. Immunofluorescence staining, Western blotting, qRT-PCR, Co-immunoprecipitation (Co-IP), IHC staining, TMA and Chromatin immunoprecipitation (ChIP) assay were performed to explore the mechanism of STAT3 modulating METTL3 localization. Cell viability, wound healing and transwell assay, and orthotopic xenograft model were used to evaluate the role of METTL3-STAT3 feedback loop in the promotion of HCC metastasis in vitro and in vivo. RESULTS: METTL3 and STAT3 are both abundantly expressed in high-metastatic HCC cells and tissues. Moreover, a positive correlation was found between the expression of STAT3 and METTL3 in HCC tissues. Mechanistically, METTL3 could induce the m6A modification of STAT3 mRNA, and then promote the translation of m6A-contained STAT3 mRNA by interacting with the translation initiation machinery. In contrast, STAT3 promoted nuclear localization of METTL3 via transcriptionally upregulating WTAP, a vital member of the methyltransferase complex, and facilitated the methyltransferase function of METTL3. METTL3 and STAT3 form a positive feedback loop to accelerate HCC metastasis in vitro and in vivo. CONCLUSIONS: Our findings reveal a novel mechanism of HCC metastasis and uncover the METTL3-STAT3 feedback signaling as a potential target for the anti-metastatic treatment of HCC. Video Abstract.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Retroalimentação , Linhagem Celular Tumoral , Metiltransferases/genética , RNA , RNA Mensageiro/genética , Fator de Transcrição STAT3/metabolismo
5.
Ecotoxicol Environ Saf ; 263: 115272, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37473704

RESUMO

Pyriclobenzuron 1(PBU) is a novel molluscicide developed to control Pomacea canaliculate, and little information on its environmental fate has been published. In this study, the photolysis of PBU in an aqueous environment was simulated using a xenon lamp. Results showed that the photolysis of PBU in water followed first-order kinetics, exhibiting a t0.5 of 95.1 h and 83.6 h in Milli-Q water and river water, respectively. Two main photolysis products 2(PPs) were detected by HPLC-UV and identified by UPLC-Q/TOF MS, which were formed via the hydroxylation and photocatalytic hydro-dehalogenation of PBU, respectively. The initial relative abundance of photolysis product 1 3(PP-1) in Milli-Q water was 1.55 times higher than that in river water. PP-1 was detected at 26.5 % and 76.8 % of the maximum relative abundance in the river water and Milli-Q water after 720 h, respectively. Photolysis product 2 4(PP-2) was stable in water because of its weak hydrophilicity. The PP-2 detected after 720 h in Milli-Q water and river water was 93.7 % and 93.5 % of the maximum relative abundance, respectively. Finally, ECOSAR software was used to evaluate the acute aquatic toxicity of PBU and its PPs, revealing that the PPs had lower toxicity levels to non-target aquatic organisms.


Assuntos
Luz Solar , Poluentes Químicos da Água , Cinética , Água , Fotólise , Poluentes Químicos da Água/toxicidade
6.
Molecules ; 28(6)2023 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-36985589

RESUMO

A simple and sensitive method for the simultaneous quantitation of prohexadione-Ca and uniconazole in the field experiment of Oryza sativa L. and Citrus reticulata Blanco was established using solid-phase extraction (SPE) with polymer anion exchange (PAX) and Florisil followed by LC-MS/MS. The method demonstrated excellent linearity (R2 > 0.999 0), trueness (recoveries between 95~105%), precision (CVs between 0.8~12%), sensitivity, and repeatability (LOQ of 0.05 and 0.01 mg/kg, respectively). Residue tests were conducted in the field at 12 representative sites in China, revealing final concentrations of prohexadione-Ca and uniconazole in brown rice, rice hull, and rice straw to be below 0.05 mg/kg, while in whole citrus fruit and citrus pulp, they were below 0.01 mg/kg. These were below the maximum residue limits specified in China. The chronic dietary risks of prohexadione-Ca and uniconazole in rice crops and citrus fruits were calculated to be 0.48% and 0.91%, respectively. Our research suggests that the chronic risk associated with the daily consumption of rice crops and citrus fruit at the recommended dosage is acceptable.


Assuntos
Citrus , Oryza , Resíduos de Praguicidas , Cromatografia Líquida/métodos , Oryza/química , Espectrometria de Massas em Tandem/métodos , Citrus/química , Resíduos de Praguicidas/análise , Cromatografia Líquida de Alta Pressão/métodos , Medição de Risco
7.
Ecotoxicol Environ Saf ; 232: 113270, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35124423

RESUMO

Pesticides are currently extensively used in agriculture, forestry, animal husbandry, and environmental hygiene, and their residues have become a global environmental problem, which can easily form combined pollution with heavy metals. The present study examined the effects of chronic (28 days) aqueous exposure of chiral penflufen (rac-penflufen, R-(-)-penflufen and S-(+)-penflufen), a widely used fungicide, with/without cadmium (Cd), a highly toxic heavy metal in zebrafish (Danio rerio). After rac-penflufen individual or combined exposure with Cd, the bioaccumulation and residual levels of S-(+)-penflufen were significantly higher than R-(-)-penflufen, and the effects of Cd were insignificantly. But for penflufen enantiomer, the effects of Cd were more serious for R-(-)-penflufen, which could increase the bioaccumulation (up to1.73 times), inhibit the dissipation (up to 32.3%) and enhance the residue (up to 5.35 times) of R-(-)-penflufen in zebrafish, decreasing the enantioselectivity. However, significant increase of S-(+)-penflufen concentrations was only found in viscera under co-exposure of Cd. The tissue distribution of penflufen enantiomers were not affected by the presence of Cd, and no interconversion of the two enantiomers occurred regardless of the presence of Cd. These findings indicated that co-contamination with Cd could increase the persistence of R-(-)-penflufen in zebrafish, thus increasing the environmental risks. The significant differences of Cd effects on chiral pesticide enantiomer and racemate indicated that the combined pollution of heavy metal and chiral pesticide might have enantiomer-specific, which should raise concern, and the enantioselective mechanism deserve further study.


Assuntos
Cádmio , Peixe-Zebra , Anilidas , Animais , Bioacumulação , Cádmio/toxicidade , Estereoisomerismo
8.
Ecotoxicol Environ Saf ; 222: 112534, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34311429

RESUMO

Penflufen fungicide is widely used as a racemate, which has potential ecological risks to aquatic organisms, while its enantioselective toxicity data is limited. This study aimed to differentiate the enantioselective toxicity difference of penflufen enantiomers, and illuminate the enantioselective mechanism from the insight of enantiomer-protein specific binding. The semipreparative separation and absolute configuration of penflufen enantiomers were conducted. The acute toxicity of S-(+)-penflufen was 54 times higher than R-(-)-penflufen to Danio rerio, and the coexistence of R-(-)-penflufen could increase the exposure risk of S-(+)-penflufen. For chronic toxicity, after low-dose long-term exposure, rac-penflufen and S-(+)-penflufen inducted more serious oxidative stress than R-(-)-penflufen in D. rerio, and inhibited the succinate dehydrogenase (SDH) activity significantly. For target phytopathogen, the toxicity difference of S-(+)-penflufen and R-(-)-penflufen was up to 148 times for Rhizoctonia solani. Based on the toxic unit analysis, the toxic interactions of antagonistic effect and concentration addition were found between penflufen enantiomers, indicating the coexistence of R-(-)-penflufen could increase overuse and environmental risks. Computational chemistry was used to illuminate the enantioselectivity mechanism, and the lower binding energy between the active site of SDH and S-(+)-penflufen contributed to the higher toxicity. The higher target toxicity might be due to the hydrophobic pocket of CybL in R. solani was more benefited to S-(+)-penflufen binding SDH than Botrytis cinerea. These results could be helpful for further understanding the potential risk of chiral penflufen in the environment, demonstrating the importance of understanding the enantioselective difference of chiral pesticides, and providing a new insight for analyzing the enantioselective mechanism.


Assuntos
Fungicidas Industriais , Anilidas , Botrytis , Química Computacional , Fungicidas Industriais/toxicidade , Rhizoctonia , Estereoisomerismo
9.
Zhongguo Dang Dai Er Ke Za Zhi ; 22(4): 294-298, 2020 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-32312364

RESUMO

OBJECTIVE: To study the clinical features of children with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. METHODS: A retrospective analysis was performed for the clinical data of 13 children with SARS-CoV-2 infection who hospitalized in a Changsha hospital. RESULTS: All 13 children had the disease onset due to family aggregation. Of the 13 children, 2 had no symptoms, and the other 11 children had the clinical manifestations of fever, cough, pharyngeal discomfort, abdominal pain, diarrhea, convulsions, or vomiting. As for clinical typing, 7 had mild type, 5 had common type, and 1 had severe type. The median duration of fever was 2 days in 6 children. All 13 children had normal levels of peripheral blood lymphocyte counts, immunoglobulins, CD4, CD8, and interleukin-6. The median time to clearance of SARS-CoV-2 was 13 days in the nasopharyngeal swabs of the 13 children. Three children presented false negatives for RT-PCR of SARS-CoV-2. SARS-CoV-2 RNA remained detectable in stools for 12 days after the nasopharyngeal swab test yielded a negative result. Abnormal CT findings were observed in 6 children. All 13 children were cured and discharged and they were normal at 2 weeks after discharge. CONCLUSIONS: Intra-family contact is the main transmission route of SARS-CoV-2 infection in children, and there is also a possibility of fecal-oral transmission. Mild and common types are the major clinical types in children with SARS-CoV-2 infection, and cytokine storm is not observed. Children with SARS-CoV-2 infection tend to have a good short-term prognosis, and follow-up is needed to observe their long-term prognosis. Multiple nucleic acid tests should be performed for patients with SARS-CoV-2 infection and their close contacts by multiple site sampling.


Assuntos
Betacoronavirus , Infecções por Coronavirus , Pandemias , Pneumonia Viral , Dor Abdominal/etiologia , Doenças Assintomáticas , Betacoronavirus/patogenicidade , Biomarcadores/análise , COVID-19 , Teste para COVID-19 , Criança , China , Técnicas de Laboratório Clínico , Infecções por Coronavirus/complicações , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/transmissão , Tosse/etiologia , Diarreia/etiologia , Fezes/virologia , Febre/etiologia , Humanos , Contagem de Linfócitos , Pneumonia Viral/complicações , Pneumonia Viral/diagnóstico , Pneumonia Viral/imunologia , Pneumonia Viral/transmissão , RNA Viral/análise , Estudos Retrospectivos , SARS-CoV-2 , Convulsões/etiologia , Tomografia Computadorizada por Raios X
10.
Environ Sci Technol ; 52(3): 1320-1329, 2018 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-29287146

RESUMO

Exploring the migration behaviors of selenium in granite is critical for the safe disposal of radioactive waste. The matrix diffusion and sorption of 75Se(IV) (analogue for 79Se) in granite were systematically studied to set reliable parameters in this work. Through-diffusion and batch sorption experiments were conduct with four types of Beishan granite. The magnitudes of the obtained apparent diffusion coefficient (Da) values are of the following order: monzogranite > granodiorite-2 > granodiorite-1, which is opposite to the sequence of the Kd values obtained from both the diffusion model and batch sorption experiments. The EPMA results of the granitic flakes showed that there was no obvious enrichment of Se(IV) on quartz, microcline and albite. Only biotite showed a weak affinity for Se(IV). Macroscopic sorption behaviors of Se(IV) on the four types of granite were identical with the sequence of the granitic biotite contents. Quantitative fitting results were also provided. XPS and XANES spectroscopy data revealed that bidentate inner-sphere complexes were formed between Se(IV) and Fe(III). Our results indicate that biotite can be representative of the Se(IV) sorption in complex mineral assemblages such as granite, and the biotite contents are critically important to evaluate Se(IV) transport in granite.


Assuntos
Compostos Férricos , Selênio , Adsorção , Difusão , Dióxido de Silício
11.
J Sep Sci ; 41(11): 2419-2431, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29510467

RESUMO

As a key representative organism, earthworms can directly illustrate the influence of pesticides on environmental organisms in soil ecosystems. The present work aimed to develop a high-throughput multipesticides residue analytical method for earthworms using solid-liquid extraction with acetonitrile as the solvent and magnetic material-based dispersive solid-phase extraction for purification. Magnetic Fe3 O4 nanoparticles were modified with a thin silica layer to form Fe3 O4 -SiO2 nanoparticles, which were fully characterized by field-emission scanning electron microscopy, transmission electron microscopy, Fourier-transform infrared spectroscopy, X-ray diffractometry, and vibrating sample magnetometry. The Fe3 O4 -SiO2 nanoparticles were used as the separation media in dispersive solid-phase extraction with primary secondary amine and ZrO2 as the cleanup adsorbents to eliminate matrix interferences. The amounts of nanoparticles and adsorbents were optimized for the simultaneous determination of 44 pesticides and six metabolites in earthworms by liquid chromatography with tandem mass spectrometry. The method performance was systematically validated with satisfactory results. The limits of quantification were 20 µg/kg for all analytes studied, while the recoveries of the target analytes ranged from 65.1 to 127% with relative standard deviation values lower than 15.0%. The developed method was subsequently utilized to explore the bioaccumulation of bitertanol in earthworms exposed to contaminated soil, verifying its feasibility for real sample analysis.


Assuntos
Magnetismo/métodos , Nanopartículas de Magnetita/química , Oligoquetos/química , Resíduos de Praguicidas/isolamento & purificação , Extração em Fase Sólida/métodos , Adsorção , Animais , Cromatografia Líquida de Alta Pressão , Magnetismo/instrumentação , Resíduos de Praguicidas/análise , Dióxido de Silício/química , Extração em Fase Sólida/instrumentação
12.
Ecotoxicol Environ Saf ; 165: 476-483, 2018 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-30218971

RESUMO

Systematically evaluation of the metabolism, distribution and effect of imidacloprid in Chinese lizards (Eremias argus) were carried out following oral exposure. Imidacloprid-olefin-guanidine was prone to accumulate in the brain and caused potential neurotoxicity. Percutaneous and excretory excretions were the primary ways for the elimination of imidacloprid and its metabolites. Liver was the main site for hydroxy reduction and nitro-reduction metabolism of imidacloprid. The metabolism of imidacloprid was a complex process in which many metabolic enzymes participated. Aldehyde oxidase and CYP2C9 were the key enzymes in nitro-reduction process. CYP3A4 dominated the process of hydroxylation and desaturation. The increase in Glutathione S-transferase expression may be related to the removal of imidacloprid, but also related to the oxidative stress reaction that imidacloprid may cause in tissues, especially in the kidney. The findings enrich and supplement the knowledge of the environmental fate of imidacloprid in reptiles.


Assuntos
Inseticidas , Lagartos/metabolismo , Neonicotinoides , Neurotoxinas , Nitrocompostos , Administração Oral , Aldeído Oxidase/metabolismo , Animais , Hidrocarboneto de Aril Hidroxilases/metabolismo , Encéfalo/metabolismo , Família 3 do Citocromo P450/metabolismo , Glutationa Transferase/metabolismo , Inseticidas/metabolismo , Inseticidas/toxicidade , Rim/metabolismo , Fígado/metabolismo , Neonicotinoides/metabolismo , Neonicotinoides/toxicidade , Neurotoxinas/metabolismo , Neurotoxinas/toxicidade , Nitrocompostos/metabolismo , Nitrocompostos/toxicidade , Reação em Cadeia da Polimerase
13.
Ecotoxicol Environ Saf ; 163: 63-68, 2018 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-30036758

RESUMO

Effective and safe acaricides based on scientific data are needed for that no chemical acaricides has been registered for the control of two-spotted spider mite in strawberry crops in China. To identify suitable acaricides, the efficacy, persistence, and toxicity of eight acaricides (hexythiazox, fenpyroximate, chlorfenapyr, propargite, etoxazole, bifenazate, spirodiclofen, and pyridaben) on greenhouse strawberries were tested. The eight acaricides were ranked, from highest average efficacy at the recommended dosage to lowest, as follows: etoxazole > bifenazate > fenpyroximate > propargite > spirodiclofen > pyridaben > hexythiazox> chlorfenapyr. The average recoveries of the eight acaricides at the spiking levels of 0.05 and 0.5 mg/L ranged from 72.4% to 108.1% (relative standard deviation, 1.3-8.8%). The concentrations of hexythiazox, fenpyroximate, etoxazole, bifenazate, spirodiclofen, and pyridaben at 5 days after application were lower than the maximum residue limits (MRLs) specified by China, the European Union (EU), the Codex Alimentarius Commission, and Japan, but those of chlorfenapyr and propargite residues were 8.8 and 1.9 times higher than the MRLs in the EU. Only propargite posed a high chronic dietary risk to humans. Pyridaben and chlorfenapyr showed unacceptable ecotoxicology risks for honeybees (hazard quotient values of > 50). The recommended acaricides to control spider mites in greenhouse-grown strawberry crops are etoxazole, bifenazate, fenpyroximate, spirodiclofen, and hexythiazox based on the efficacy, persistence and toxicity.


Assuntos
Acaricidas/toxicidade , Contaminação de Alimentos/análise , Fragaria/metabolismo , Tetranychidae/efeitos dos fármacos , Adulto , Animais , Abelhas , China , Fragaria/parasitologia , Humanos , Medição de Risco , Tetranychidae/fisiologia
14.
Ecotoxicol Environ Saf ; 160: 127-133, 2018 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-29793201

RESUMO

Methylated vegetable oil adjuvants can enhance initial deposition and decrease the required dosages of pesticides sprayed on plants, so an oil adjuvant mixed with fungicides were used to prevent and control gray mold in greenhouse strawberry. As the persistence and dietary exposure risks from fungicides on strawberries after using adjuvants have not been assessed, the efficacy, dissipation and safety of pyrimethanil and boscalid in the presence and absence of a methylated vegetable oil adjuvant were evaluated. To better describe the actual use of fungicides in greenhouse strawberry, twice repeated application of fungicides were conducted follower by an optimized QuEChERS pre-treatment method. When applied at 60% of their recommended dosages with the adjuvant, the efficacy of pyrimethanil and boscalid for gray mold was similar to that shown by the treatment of 100% fungicides in absence of the adjuvant based on Duncan's Multiple-Range test, and their average residues increased to 89.0% and 89.3%, respectively. The adjuvant enhanced the accumulation effect of pyrimethanil residue by 31.7% after repeated applications, and the half-lives were similar (5.2 and 4.2 d). The adjuvant had comparable accumulation effects (1.75 and 1.83) and similar half-lives (5.4 and 5.5 d) for boscalid. In absence of adjuvant, the risk quotients (RQs) of pyrimethanil (0.41 and 0.33) and boscalid (0.49 and 0.63) after twice applications at pre-harvest interval were lower than 1. Adding the methylated vegetable oil adjuvant to fungicides would result in unprolonging half-life and acceptably low dietary exposure risk on strawberries, but lower dosage of fungicides were used.


Assuntos
Compostos de Bifenilo/administração & dosagem , Fragaria , Fungicidas Industriais/administração & dosagem , Niacinamida/análogos & derivados , Resíduos de Praguicidas/análise , Óleos de Plantas/administração & dosagem , Pirimidinas/administração & dosagem , Compostos de Bifenilo/análise , Botrytis/efeitos dos fármacos , Fragaria/química , Fragaria/microbiologia , Fungicidas Industriais/análise , Niacinamida/administração & dosagem , Niacinamida/análise , Doenças das Plantas/prevenção & controle , Óleos de Plantas/análise , Pirimidinas/análise
15.
BMC Cancer ; 17(1): 477, 2017 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-28693517

RESUMO

BACKGROUND: Jumonji C domain 2A (JMJD2A), as a histone demethylases, plays a vital role in tumorigenesis and progression. But, its functions and underlying mechanisms of JMJD2A in nasopharyngeal carcinoma (NPC) metabolism are remained to be clarified. In this study, we investigated glycolysis regulation by JMJD2A in NPC and the possible mechanism. METHODS: JMJD2A expression was detected by Western blotting and Reverse transcription quantitative real-time PCR analysis. Then, we knocked down and ectopically expressed JMJD2A to detect changes in glycolytic enzymes. We also evaluated the impacts of JMJD2A-lactate dehydrogenase A (LDHA) signaling on NPC cell proliferation, migration and invasion. ChIP assays were used to test whether JMJD2A bound to the LDHA promoter. Finally, IHC was used to verify JMJD2A and LDHA expression in NPC tissue samples and analyze their correlation between expression and clinical features. RESULTS: JMJD2A was expressed at high levels in NPC tumor tissues and cell lines. Both JMJD2A and LDHA expression were positively correlated with the tumor stage, metastasis and clinical stage. Additionally, the level of JMJD2A was positively correlated with LDHA expression in NPC patients, and higher JMJD2A and LDHA expression predicted a worse prognosis. JMJD2A alteration did not influence most of glycolytic enzymes expression, with the exception of PFK-L, PGAM-1, LDHB and LDHA, and LDHA exhibited the greatest decrease in expression. JMJD2A silencing decreased LDHA expression and the intracellular ATP level and increased LDH activity, lactate production and glucose utilization, while JMJD2A overexpression produced the opposite results. Furthermore, JMJD2A could combine to LDHA promoter region and regulate LDHA expression at the level of transcription. Activated JMJD2A-LDHA signaling pathway promoted NPC cell proliferation, migration and invasion. CONCLUSIONS: JMJD2A regulated aerobic glycolysis by regulating LDHA expression. Therefore, the novel JMJD2A-LDHA signaling pathway could contribute to the Warburg effects in NPC progression.


Assuntos
Carcinoma/genética , Carcinoma/metabolismo , Regulação Neoplásica da Expressão Gênica , Histona Desmetilases com o Domínio Jumonji/metabolismo , L-Lactato Desidrogenase/genética , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/metabolismo , Trifosfato de Adenosina/metabolismo , Adulto , Idoso , Biomarcadores , Carcinoma/mortalidade , Carcinoma/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células , Progressão da Doença , Ativação Enzimática , Feminino , Expressão Gênica , Genes Reporter , Glucose/metabolismo , Glicólise , Humanos , Isoenzimas/genética , Isoenzimas/metabolismo , Estimativa de Kaplan-Meier , L-Lactato Desidrogenase/metabolismo , Lactato Desidrogenase 5 , Ácido Láctico/metabolismo , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/mortalidade , Neoplasias Nasofaríngeas/patologia , Gradação de Tumores , Estadiamento de Neoplasias , Transdução de Sinais , Transcrição Gênica
16.
J Sep Sci ; 40(11): 2438-2450, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28426177

RESUMO

We aimed to develop an efficient cleanup method for multi-pesticides residue analysis in complex plant matrices, shallot, ginger, garlic, onion, leek, and celery. Column chromatography was used as the cleanup method and fabricated with florisil and graphitized carbon black as the adsorbents. The amount of the graphitized carbon black adsorbent and the choice of the elution solvent were systematically investigated for exploring the best combination. The target pesticides covered organochlorine, pyrethroid, and organophosphorus pesticides, and were 38 in total. The method validation and comparison were performed to verify its feasibility and advantages in operation convenience and purification efficiency. The method limit of quantitation varied from 0.01 to 0.03 mg/kg, which depends on the pesticides and the sample matrices. The recoveries of the pesticides ranged from 60.5 to 128% (RSD ≤ 19.0%) at the spiked concentration level of 0.01 (or 0.03) mg/kg and 62.9 to 130% (RSD ≤ 13.0%) at 0.1 mg/kg. Compared with the commercial cleanup solid-phase extraction cartridges, the present adsorbent combination displayed better purification effect and shorter sample pretreatment time, demonstrating potential application prospect in the complex matrix sample analysis.


Assuntos
Contaminação de Alimentos/análise , Resíduos de Praguicidas/análise , Verduras/química , Cromatografia Gasosa-Espectrometria de Massas , Extração em Fase Sólida
17.
Tumour Biol ; 37(2): 1919-31, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26330294

RESUMO

Cyclopamine (CPM) showed promise as a human cancer chemotherapy agent. However, limitations such as stomach acid instability and low solubility impair its clinical application. In this study, we synthesized a novel CPM analogue, isocyclopamine (ICPM), which had comparative bioactivity with CPM and improved stability and solubility. ICPM reversed doxorubicin resistance and had potent synergy with doxorubicin in MCF-7/ADR cells. We further demonstrated that the synergistic mechanism was related to the increased intracellular accumulation of doxorubicin in the cells and the downregulation of the cancer stem-like cells via modulation on both ABCB1 and ABCG2 transporters with independence of Smoothened. The present study identified ICPM as a novel derivative of CPM with better stability and solubility, which provided a useful tool for the biological and medicinal studies, as well as a novel agent for the development of new cancer chemotherapy with improved efficacy.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Regulação para Baixo/efeitos dos fármacos , Doxorrubicina/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Células-Tronco Neoplásicas/efeitos dos fármacos , Alcaloides de Veratrum/farmacologia , Células A549 , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células HCT116 , Células HeLa , Humanos , Células MCF-7 , Células-Tronco Neoplásicas/metabolismo
18.
Tumour Biol ; 37(5): 6227-38, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26615422

RESUMO

13-Oxyingenol dodecanoate (13OD) is an ingenol derivative prepared from Chinese traditional medicine Euphorbia kansui without any report about its bioactivity. The present study demonstrated for the first time that 13OD displayed potent cytotoxicity against chronic myeloid leukemia K562 cells in vitro. 13OD inhibited proliferation, induced G2/M phase arrest, and exhibited potent apoptotic activity in K562 cells. In K562 cells, 13OD disrupted the mitochondrial membrane potential and induced high level of ROS, which played an indispensable role in 13OD-induced apoptosis. Further investigations on the molecular mechanisms revealed that total Akt protein level was decreased in a caspase-dependent way after treatment with 13OD; in addition, ERK was activated by 13OD, and this activation played a protective role in 13OD stimulation. Altogether, these results revealed that the cytotoxic ingenol derivative 13OD induced apoptosis with novel mechanisms for the proapoptotic function in cancer cells, and suggested that 13OD may serve as a lead template for rational drug design and for future anticancer agent development.


Assuntos
Apoptose/efeitos dos fármacos , Diterpenos/administração & dosagem , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Proteínas Proto-Oncogênicas c-akt/genética , Caspases/genética , Proliferação de Células/efeitos dos fármacos , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Humanos , Células K562 , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos
19.
J Clin Lab Anal ; 30(6): 1175-1182, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27291965

RESUMO

BACKGROUND: Many anesthesia methods have been studies in hepatocellular carcinoma (HCC). We aimed to explore the effects of combined intravenous and inhalation anesthesia and combined general and epidural anesthesia on cellular immune function and neuroendocrine function in patients with HCC before and after surgery. METHODS: Between September 2012 and April 2014, 72 patients who underwent a hepatectomy in our hospital were enrolled. RESULTS: Compared with the combined intravenous and inhalation anesthesia group, the combined general and epidural anesthesia group demonstrated increased CD4+ /CD8+ T cells 0 hr after surgery, increased CD3+ , CD4+ , CD4+ /CD8+ cells, and IFN-γ levels 12 hr after surgery, and increased CD3+ , CD4+ , and CD4+ /CD8+ cells 24 hr after surgery (all P < 0.05). At 72 hr after surgery, the levels of ACTH and Cor in the combined general and epidural anesthesia group, and the levels of CD3+ , CD4+ , CD4+ /CD8+ cells, and IFN-γ in both the combined intravenous and inhalation anesthesia and the combined general and epidural anesthesia groups decreased to pre-surgery levels. Significant differences were observed in the comparisons of CD3+ , IL-6, and IL-10 between the combined intravenous and inhalation anesthesia and the combined general and epidural anesthesia groups 72 hr after surgery (all P < 0.05). CONCLUSION: Our results revealed that combined general and epidural anesthesia plays a crucial role in hepatectomy via the mitigation of the inhibition of immunologic function in HCC patients during the perioperative period. Combined general and epidural anesthesia also hastens the recovery of immunologic suppression after surgery, which can provide a certain reference for the selection of clinical anesthesia in the treatment of HCC.


Assuntos
Anestesia/métodos , Carcinoma Hepatocelular , Sistema Endócrino/efeitos dos fármacos , Hepatectomia/métodos , Imunidade Celular/efeitos dos fármacos , Resultado do Tratamento , Hormônio Adrenocorticotrópico/sangue , Adulto , Idoso , Carcinoma Hepatocelular/sangue , Carcinoma Hepatocelular/imunologia , Carcinoma Hepatocelular/terapia , Citocinas/sangue , Feminino , Humanos , Hidrocortisona/sangue , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Estudos Retrospectivos , Subpopulações de Linfócitos T/patologia
20.
Pharm Biol ; 53(1): 1-9, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25026337

RESUMO

CONTEXT: The rizoma of Pulsatilla chinensis (Bunge) Regel has been used as a traditional Chinese medicinal herb for thousands of years. Total saponins from P. chinensis can induce the apoptosis of solid cancer cells; however, their activity on chronic myeloid leukemia and the mechanisms remains unknown. OBJECTIVE: To study the activity of total saponins and the main active fractions from P. chinensis saponins on chronic myeloid leukemia, and to illustrate the mechanisms underlying the anticancer activities. MATERIALS AND METHODS: The cytotoxic activity were assayed by MTT; cell cycle arrest and apoptosis were tested by flow cytometry system; changes in the mitochondrial membrane potential were determined using JC-1; and the apoptosis signaling pathway was determined by western blotting. RESULTS: We demonstrated that total P. chinensis saponin displayed cytotoxic activity against K562 cell line. In addition, we identified 23-hydroxybetulinic acid (HBA), pulchinenoside A (PA), and anemoside B4 (AB4) from the total saponins, with the most cytotoxic compound HBA. Glycosylation at C3 and C28 of HBA significantly reduces its cytotoxicity. HBA could promote cell cycle arrest at S phase and induce apoptosis via intrinsic pathway. HBA disrupts mitochondrial membrane potential significantly (p < 0.01) and selectively downregulates the levels of Bcl-2, survivin and upregulates Bax, cytochrome C, cleaved caspase-9 and -3. DISCUSSION AND CONCLUSION: Total saponins from P. chinensis may be effective natural products against human chronic myelogenous leukemia; HBA is one of the bioactive components responsible for its anticancer activity, and could be further investigated as an alternative therapeutic drug for leukemia.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Medicamentos de Ervas Chinesas/farmacologia , Pulsatilla/química , Saponinas/química , Triterpenos/farmacologia , Antineoplásicos Fitogênicos/isolamento & purificação , Ciclo Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Medicamentos de Ervas Chinesas/isolamento & purificação , Citometria de Fluxo , Humanos , Células K562 , Leucemia Mielogênica Crônica BCR-ABL Positiva/metabolismo , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Estrutura Molecular , Rizoma/química , Fase S/efeitos dos fármacos , Triterpenos/isolamento & purificação
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