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1.
Environ Monit Assess ; 192(11): 692, 2020 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-33037524

RESUMO

Residue levels of seven commonly used pesticides were determined in random samples of tomatoes, French beans, and kale collected from horticultural farms in Buuri, Imenti North, and Imenti South sub-counties in Meru, Kenya, just before delivery to the consumers. QuEChERS method for extraction followed by LC-MS/MS was used to determine the concentrations. The concentrations (µg kg-1 wet weight) in French beans, kale, and tomatoes ranged from below detection limit (BDL): BDL-48.65 (carbendazim), BDL-290.76 (imidacloprid), BDL-2.81 (acetamiprid), BDL-25.76 (azoxystrobin), BDL-105.18 (metalaxyl), BDL-0.15 (diazinon), and BDL-0.17(chlorpyrifos). The maximum residue levels determined in the horticultural produce from the three regions were 290 µg kg-1 for imidacloprid in tomatoes from Buuri and 25.76 µg kg-1for azoxystrobin in French beans from Imenti South. The pesticide residue levels generally were extremely low and met the MRLs set by EU and other countries, except for carbendazim and metalaxyl in French beans, and posed no concern to human health. The estimated daily intakes (EDI) (mg kg-1 BW/day) for the population of Meru County were very low ranging from 1.685 × 10-8 (acetamiprid) to 2.381 × 10-5 (imidacloprid) in tomatoes, 2.849 × 10-9 (metalaxyl) to 3.633 × 10-7 (azoxystrobin) in French beans, and 1.392 × 10-8 (diazinon) in kale, respectively. The health risk indices were subsequently extremely low for the detectable pesticide residues, ranging from 6.74 × 10-7 (acetamiprid) to 3.97 × 10-4 (imidacloprid) in tomatoes, 3.56 × 10-8 (metalaxyl) to 5.52 × 10-5 (chlorpyrifos) in French beans, and 6.96 × 10-5 (diazinon) in kale, respectively, indicating no health risk in the population, but their presence in these vegetables cannot be ignored as long-term exposure can still cause health risks.


Assuntos
Brassica , Lycopersicon esculentum , Resíduos de Praguicidas , Praguicidas , Cromatografia Líquida , Monitoramento Ambiental , Contaminação de Alimentos/análise , Humanos , Quênia , Resíduos de Praguicidas/análise , Praguicidas/análise , Espectrometria de Massas em Tandem
2.
J Environ Qual ; 49(3): 762-768, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-33016392

RESUMO

Sulfur (S) and sulfate (SO4 2- ) in fine particulate matter (PM2.5 ) are monitored by the Interagency Monitoring of Protected Visual Environments (IMPROVE) network at remote and rural sites across the United States. Within the IMPROVE network, S is determined from X-ray fluorescence (XRF) spectroscopy from a Teflon filter, and SO4 2- is determined via ion chromatography (IC) from a nylon filter. Differences in S and SO4 2- estimates may indicate the presence of organosulfur (OS) species or biases between sampling and analytical methods. To reduce potential biases, an inductively coupled plasma-optical emission spectroscopy (ICP-OES) method was developed to allow for analysis of SO4 2- and S from a single filter extract. Sulfur (ICP-OES) and SO4 2- (IC) estimates from 2016 IMPROVE filters correlated strongly, suggesting that, on average, ICP-OES accurately estimated S. However, observed differences between slopes suggested the presence of water-soluble OS species, especially during summer. Organosulfur species are important indicators of secondary organic aerosols formed through reactions of biogenic and anthropogenic pollutants and can be quantified through laboratory techniques such as reverse-phase liquid chromatography (RPLC) or hydrophilic liquid interaction chromatography (HILIC) coupled to electrospray ionization-high-resolution tandem mass spectrometry (RPLC/ESI-HR-MS/MS and HILIC/ESI-HR-MS/MS, respectively), and field techniques using Aerodyne aerosol mass spectrometry (AMS). However, these methods are costly and introduce relatively large uncertainties when scaled for large networks such as IMPROVE. The method described in this report provides an inexpensive complement to XRF, which measures total S (insoluble and water-soluble S) to estimate water-soluble S and OS concentrations in PM.


Assuntos
Nylons , Espectrometria de Massas em Tandem , Aerossóis , Análise Espectral , Enxofre , Estados Unidos
3.
Wei Sheng Yan Jiu ; 49(5): 809-814, 2020 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-33070828

RESUMO

OBJECTIVE: To establish a quantitative analysis method for sennoside A, sennoside B and physcion by ultra-high performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS). METHODS: The sample was extracted by methanol-2 mmol/L ammonium formate(9∶1) at 40 ℃ for 1 h. The separation was performed using Agilent Eclipse Plus C_(18 )(2. 1 mm × 50 mm, 1. 8 µm) column with gradient elution. The mobile phase was consisted of 0. 1% formic acid and methanol. Qualitative and quantitative analysis was conducted with an electrospray ionization source operated in the negative ionization(ESI~-) mode and multiple reaction monitoring(MRM) mode. RESULTS: The linear range of three compounds were from 0. 1 to 10 µg/mL with the correlation coefficients(r) above 0. 995. The spiked recoveries were in the range of 81. 9% to 114. 5% at the concentrations of 0. 02, 0. 15 and 1. 60 mg/g with relative standard devisions(RSDs) ranged from 0. 30% to 3. 43%(n=6). The detection limits of sennoside A and sennoside B were 1. 2 µg/g. The detection limit of physcion was 2. 4 µg/g. Sennoside A, sennoside B or physcion were detected in 19 out of 40 batches of samples. The content of sennoside A ranged from 0. 184 to 6. 33 mg/g and the content of sennoside B ranged from 0. 202 to 7. 23 mg/g. The content of physcion ranged from 0. 042 to 0. 79 mg/g. CONCLUSION: The method is simple, accurate and suitable for the determination of sennoside A, sennoside B and physcion.


Assuntos
Senosídeos , Espectrometria de Massas em Tandem , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Emodina/análogos & derivados
4.
Wei Sheng Yan Jiu ; 49(5): 815-822, 2020 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-33070829

RESUMO

OBJECTIVE: The screening method was established for pesticide residues in substitutional teas such as orange peel, lotus leaf, pueraria lobata and Pangdahai using data base. The method for analyzing of 26 pesticide residues was confirmed in four substitutional teas with gas chromatography-tandem mass spectrometry(GC-MS/MS) and dispersive solid-phase extraction(d-SPE) for sample preparation. METHODS: The 26 types of pesticides were selected as target compounds, including screened out, commonly used in substitutional tea planting and forbidden in agriculture planting. The samples extracted with acetonitrile, and purified by adsorbent(e. g PSA, GCB, C_(18)), the purification solutions were separated on DB-5 MS UI column((15 m+PUU+15 m)×0. 25 mm×0. 25 µm) with programmed temperature and determined by GC-MS/MS in multi-reaction monitoring(MRM) model. The external standard method was applied to quantify the pesticides. RESULTS: The method showed a good linearity(r≥0. 995)in concentration range(2-100 µg/L) for 26 kinds of pesticides. The limits of quantification(LOQ) were 3-40 µg/kg. The average recoveries range were 71. 9%-114. 4% in three add levels of 10, 50, 200 µg/kg, and relative standard deviations of 1. 0%-16. 0%(n=6). In the four matrixes, the pesticides were detected concentrating on orange peel, and there were kinds of residues. CONCLUSION: This method is simple, fast, sensitive, selective and can satisfy the request of pesticide screening and simultaneous analysis of multiple pesticide residues in orange peel, lotus leaf, pueraria lobata and Pangdahai.


Assuntos
Citrus sinensis , Lotus , Resíduos de Praguicidas , Pueraria , Medicamentos de Ervas Chinesas , Cromatografia Gasosa-Espectrometria de Massas , Resíduos de Praguicidas/análise , Espectrometria de Massas em Tandem , Chá
5.
Wei Sheng Yan Jiu ; 49(5): 829-867, 2020 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-33070831

RESUMO

OBJECTIVE: To establish an analytical method for determination of 20 kinds of ß-receptor blockers residues in animal foods by ultra high performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS). METHODS: The samples of animal foods were enzymatic hydrolysis by trichloroacetic acid(TCA), purified by MCX column. The separation was performed on a Waters ACQUITYTM BEH C_(18 )column(100 mm×2. 1 mm, 1. 7 µm), then the target compounds were detected by UPLC-MS/MS with ESI positive ion scan in mode of multiple reaction monitoring(MRM) and quantified by matrix matched external standard method. RESULTS: At the spiked level of 1, 2 and 4 µg/kg, the recoveries of each compound were in the range of 61. 9%-119. 1% with the relative standard deviations of 1. 5%-28. 4%(n=6). The qualitative limits of detections were 0. 01-0. 15 µg/kg and the quantitative limits were 0. 03-0. 50 µg/kg for the 20 targets compounds. By using the established method, the target compounds in 30 animal foods were detected, and no excessive veterinary drug residue were detected. CONCLUSION: The established method is simple, rapid, high sensitivity and good stability, with a wide variety and a certain development. It can provide more convenient and fast detection method support for the daily monitoring of veterinary drug residues in animal foods.


Assuntos
Contaminação de Alimentos , Espectrometria de Massas em Tandem , Ração Animal , Animais , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Contaminação de Alimentos/análise
6.
Nat Commun ; 11(1): 4935, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-33004797

RESUMO

Gramicidin A (1) is a peptide antibiotic that disrupts the transmembrane ion concentration gradient by forming an ion channel in a lipid bilayer. Although long used clinically, it is limited to topical application because of its strong hemolytic activity and mammalian cytotoxicity, likely arising from the common ion transport mechanism. Here we report an integrated high-throughput strategy for discovering analogues of 1 with altered biological activity profiles. The 4096 analogue structures are designed to maintain the charge-neutral, hydrophobic, and channel forming properties of 1. Synthesis of the analogues, tandem mass spectrometry sequencing, and 3 microscale screenings enable us to identify 10 representative analogues. Re-synthesis and detailed functional evaluations find that all 10 analogues share a similar ion channel function, but have different cytotoxic, hemolytic, and antibacterial activities. Our large-scale structure-activity relationship studies reveal the feasibility of developing analogues of 1 that selectively induce toxicity toward target organisms.


Assuntos
Antibacterianos/farmacologia , Descoberta de Drogas/métodos , Gramicidina/análogos & derivados , Ensaios de Triagem em Larga Escala/métodos , Animais , Antibacterianos/química , Linhagem Celular Tumoral , Química Farmacêutica , Eritrócitos , Estudos de Viabilidade , Bactérias Gram-Positivas/efeitos dos fármacos , Gramicidina/química , Gramicidina/farmacologia , Hemólise/efeitos dos fármacos , Concentração Inibidora 50 , Camundongos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Coelhos , Relação Estrutura-Atividade , Espectrometria de Massas em Tandem
7.
Zhongguo Zhong Yao Za Zhi ; 45(15): 3726-3739, 2020 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-32893565

RESUMO

This study is to explore the effect of Qingfei Paidu Decoction(QPD) on the host metabolism and gut microbiome of rats with metabolomics and 16 S rDNA sequencing. Based on 16 S rDNA sequencing of gut microbiome and metabolomics(GC-MS and LC-MS/MS), we systematically studied the serum metabolites profile and gut microbiota composition of rats treated with QPD for continued 5 days by oral gavage. A total of 23 and 43 differential metabolites were identified based on QPD with GC-MS and LC-MS/MS, respectively. The involved metabolic pathways of these differential metabolites included glycerophospholipid metabolism, linoleic acid metabolism, TCA cycle and pyruvate metabolism. Meanwhile, we found that QPD significantly regulated the composition of gut microbiota in rats, such as enriched Romboutsia, Turicibacter, and Clostridium_sensu_stricto_1, and decreased norank_f_Lachnospiraceae. Our current study indicated that short-term intervention of QPD could significantly regulate the host metabolism and gut microbiota composition of rats dose-dependently, suggesting that the clinical efficacy of QPD may be related with the regulation on host metabolism and gut microbiome.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Microbioma Gastrointestinal/efeitos dos fármacos , Animais , Bactérias/classificação , Cromatografia Líquida , Metabolômica , Ratos , Espectrometria de Massas em Tandem
8.
PLoS One ; 15(9): e0238381, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32881942

RESUMO

Small fructans improve plant tolerance for cold stress. However, the underlying molecular mechanisms are poorly understood. Here, we have demonstrated that the small fructan tetrasaccharide nystose improves the cold stress tolerance of primary rice roots. Roots developed from seeds soaked in nystose showed lower browning rate, higher root activity, and faster growth compared to seeds soaked in water under chilling stress. Comparative proteomics analysis of nystose-treated and control roots identified a total of 497 differentially expressed proteins. GO classification and KEGG pathway analysis documented that some of the upregulated differentially expressed proteins were implicated in the regulation of serine/threonine protein phosphatase activity, abscisic acid-activated signaling, removal of superoxide radicals, and the response to oxidative stress and defense responses. Western blot analysis indicated that nystose promotes the growth of primary rice roots by increasing the level of RSOsPR10, and the cold stress-induced change in RSOsPR10levelis regulated by jasmonate, salicylic acid, and abscisic acid signaling pathways in rice roots. Furthermore, OsMKK4-dependentmitogen-activated protein kinase signaling cascades may be involved in the nystose-induced cold tolerance of primary rice roots. Together, these results indicate that nystose acts as an immunostimulator of the response to cold stress by multiple signaling pathways.


Assuntos
Resposta ao Choque Frio/efeitos dos fármacos , Oligossacarídeos/farmacologia , Oryza/metabolismo , Proteínas de Plantas/metabolismo , Proteômica/métodos , Transdução de Sinais/efeitos dos fármacos , Ácido Abscísico/metabolismo , Cromatografia Líquida de Alta Pressão , Resposta ao Choque Frio/genética , Ciclopentanos/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Oryza/efeitos dos fármacos , Oryza/crescimento & desenvolvimento , Oxilipinas/metabolismo , Fenótipo , Proteínas de Plantas/genética , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Ácido Salicílico/metabolismo , Transdução de Sinais/genética , Espectrometria de Massas em Tandem
9.
Nan Fang Yi Ke Da Xue Xue Bao ; 40(7): 995-1000, 2020 Jul 30.
Artigo em Chinês | MEDLINE | ID: mdl-32895151

RESUMO

OBJECTIVE: To study the plasma concentration and pharmacokinetics of 3, 29-Dibenzoyl Karounitriol (3, 29-DK) from sustained- release pellets and extracts of Trichosanthes at different time points in rats using high-performance liquid chromatography- tandem mass spectrometry (LC-MS/MS). METHODS: Healthy male SD rats were given a single gavage of Trichosanthes sustained-release pellets or Trichosanthes extract, and orbital blood samples were taken at different time points within 48 h after drug administration in the pellet group and within 5 h in Trichosanthes extract group for determination of the plasma concentrations of 3, 29-DK using LC-MS/MS. The standard curve of 3, 29-DK content was established, and the specificity, minimum detection limit, precision and accuracy, extraction recovery, stability and matrix effect of LC-MS/MS analysis were assessed. The mean plasms levels of 3, 29-DK at different time points after the drug administration were determined and its pharmacokinetic parameters were calculated using Das 2.0 software. RESULTS: LC-MS/MS analysis showed a good linearity of 3, 29-DK concentration within the range of 0.5-32 ng/mL, and the results of methodological validation confirmed the validity of this method for biological sample determination. Trichosanthes sustained-release pellets and Trichosanthes extract showed significant differences in their AUC(0-t), AUC(0-∞), MRT(0-t), MRT(0-∞), t1/2z and Tmax of 3, 29-DK after administration in rats (P < 0.05). CONCLUSIONS: Trichosanthes sustained-release pellets are capable of sustained-release of 3, 29-DK in rats, and thus provides a basis for the study of new dosage forms of Trichosanthes.


Assuntos
Trichosanthes , Animais , Cromatografia Líquida de Alta Pressão , Preparações de Ação Retardada , Masculino , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem
10.
Zhongguo Zhong Yao Za Zhi ; 45(16): 3826-3836, 2020 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-32893577

RESUMO

Magnolia officinalis is a traditional Chinese medicine,with many years of cultivating process, M. officinalis leaves show more differentiation types due to the exchange of seeds from different provenances. "Da Ao"(DA), "Xiao Ao"(XA), "Chuan Hou"(CH),and "Liu Ye"(LY)are the main types of M. officinalis in Sichuan province of China,and there were obvious differences in growth rate,chemical composition,leaf shape and leaf colour. This study selected different types of M. officinalis leaves(DA,XA,LY and CH)from Sichuan to determine their chlorophyll content. Transcriptomic level sequencing of different types of M. officinalis leaf tissues was by high-throughput sequencing analysis and proteomics used an integrated approach involving TMT labelling and LC-MS/MS to quantify the dynamic changes of the whole proteome of M. officinalis. The results showed that CH had the lowest chlorophyll content while DA had the highest chlorophyll content. Furthermore,transcriptome and proteomics results showed that chlorophyll synthesis pathway in DA glutamine-tRNA reductase,urinary porphyrins decarboxylase(UROD),oxygen-dependent protoporphyrin(ODCO),the original-Ⅲ oxidase protoporphyrin oxidase(PPO),magnesium chelating enzyme subunit ChlD,protoporphyrin magnesium Ⅸ monomethyl ester [oxidative] cyclase(MPPMC)were significantly higher than CH,XA and LY,consistent in the results of determination of chlorophyll content(chlorophyll content was highest of 37.56 mg·g~(-1) FW). Some rate-limiting enzymes related to the chlorophyll synthesis,such as ODCO,PPO and MPPMC were tested by Parallel Reaction Monitoring(PRM),and the results showed that the rate-limiting enzyme content in DA was higher than that in other three types. Therefore,based on the differences in leaf color of four types of M. officinalis,the research conducted a preliminary study on the chlorophyll metabolism pathway in leaves of different types of M. officinalis,and explored relevant genes and proteins causing leaf color differences from the molecular level,so as to lay a foundation for studying the differences in growth and development of different types of M. officinalis.


Assuntos
Magnolia , China , Clorofila , Cromatografia Líquida , Folhas de Planta , Proteoma , Espectrometria de Massas em Tandem , Transcriptoma
11.
Zhongguo Zhong Yao Za Zhi ; 45(16): 3890-3899, 2020 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-32893586

RESUMO

By using multivariate statistical analysis to evaluate essential quality, and provide scientific basis for their comprehensive utilization, we established an UHPLC-QTRAP-MS/MS method for the fast, precise, efficient determination of 21 kinds of amino acids and 10 kinds of nucleosides in different species of Dendrobium. The analysis was performed on a Waters XBridge Amide column(2.1 mm×100 mm,3.5 µm) with elution by mobile phase of 0.2% formic acid in water-0.2% formic acid in acetonitrile at a flow rate of 0.2 mL·min~(-1) with the column temperature at 30 ℃. The target compounds were analyzed by the positive ion multiple reaction monitoring(MRM) mode. The comprehensive evaluation of different species of Dendrobium was carried out by PCA and TOPSIS analysis. All 21 kinds of amino acids and 10 nucleosides showed good linearity among certain concentration range(r>0.999), the RSDs of the stability, precision, and repeatability tests were less than 3.0%. The recovery rate was in the range from 93.31% to 107.5%, and RSD was in the range of 1.1%-3.7%. The comprehensive evaluation index obtained with PCA showed that D. huoshanense was significantly higher than others regarding amino acids and D. officinale has higher nucleosides than other species. The biggest C_i difference of TOPSIS was 68.7%, and comprehensive evaluation showed that D. huoshanense produced the highest comprehensive quality. The method is precise, fast and efficient and can provide reliable basis for further researches and intrinsic quality control of Dendrobium.


Assuntos
Dendrobium , Espectrometria de Massas em Tandem , Aminoácidos , Cromatografia Líquida de Alta Pressão , Nucleosídeos
12.
Zhongguo Zhong Yao Za Zhi ; 45(16): 3900-3907, 2020 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-32893587

RESUMO

A highly sensitive monoclonal antibody against aflatoxin B_1(AFB_1) was prepared and an indirect competition enzyme-linked immunosorbent assay(ic-ELISA) was established based on the antibody which was used for high-throughput and rapid screening of AFB_1 contamination in Chinese herbal medicines to ensure the safety of medication. In this study, the structure of AFB_1 was modified by improved oxime method, and the carrier protein was coupled by EDC-NHS method to obtain the complete antigen of AFB_1, which was more convenient and environmental friendly. The Balb/c female mice were immunized using increasing the immunization dose and various ways of injection, and finally the AFB_1 monoclonal antibody was prepared. The AFB_1 monoclonal antibody belongs to IgG_(2 b) immunoglobulin by identifying its immunological characteristics, and its sensitivity(IC_(50)) can reach 0.15 µg·L~(-1), and the affi-nity is 2.81×10~8 L·mol~(-1). The cross-reaction rates of AFB_2, AFG_1, and AFG_2 were 35.07%, 8.75%, and 1.15%, respectively, and there was almost no cross-reactivity with other mycotoxins. Based on the high sensitivity and specificity of the antibody, an ic-ELISA method was established and applied to the determination of AFB_1 contamination in Ziziphi Spinosae Semen. According to the matrix matching standard curve, the linear concentration range for AFB_1 was 0.05-0.58 µg·L~(-1)(R~2=0.992), the recoveries were 88.00%-119.0%, and the detection limit was 1.69 µg·kg~(-1). The AFB_1 in 33 batches of Ziziphi Spinosae Semen samples was determined by ic-ELISA, and the contamination level was 3.62-206.58 µg·kg~(-1). The linear correlation coefficient between the detection results of ic-ELISA and UHPLC-MS/MS was 0.996, and there were no false positive and false negative cases. It indicates that the established ic-ELISA is accurate and reliable, and could provide a simple and effective technique for fast screening of AFB_1 contamination in Ziziphi Spinosae Semen, and also could be considered as the reference for the detection and monitoring of AFB_1 contamination in other Chinese herbal medicines.


Assuntos
Aflatoxina B1/análise , Sêmen/química , Animais , Anticorpos Monoclonais , Contaminação de Medicamentos , Ensaio de Imunoadsorção Enzimática , Feminino , Camundongos , Espectrometria de Massas em Tandem
13.
Sci Total Environ ; 740: 139696, 2020 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-32927529

RESUMO

China has the world's largest burden of Hepatitis B virus (HBV) infection, with 86 million HBV carriers, including 32 million chronic Hepatitis B patients. To monitor the HBV prevalence in near real-time, a wastewater-based epidemiology (WBE) method by using lamivudine as a biomarker was conducted in 19 cities in the Southern part of China. LC-MS/MS was utilized to quantify lamivudine in sewage, and satisfactory method validation results were achieved. The average concentration of lamivudine in sewage was 156.4 ±â€¯107.1 ng/L, and the daily consumption was 30.1 ±â€¯19.8 mg/day/1000inh in average ranging from 0.4 to 105.5 mg/day/1000inh. The prevalence of chronic Hepatitis B was estimated to be 2.5% ±â€¯1.7% based on the prevalence of lamivudine usage, which was 0.035% ±â€¯0.023%. Besides, the estimated HBV prevalence in population aged over 15 years in 19 cities was 6.8% ±â€¯4.5% and was consistent with the previous statistical data of 7% in 2018. This research demonstrated that the estimation of HBV prevalence by WBE with lamivudine as a biomarker is feasible in big cities in Southern China.


Assuntos
Antivirais , Vírus da Hepatite B , Adolescente , China , Cromatografia Líquida , Cidades , Hepatite B , Vírus da Hepatite B/isolamento & purificação , Humanos , Prevalência , Espectrometria de Massas em Tandem , Vigilância Epidemiológica Baseada em Águas Residuárias
14.
Wei Sheng Yan Jiu ; 49(4): 564-568, 2020 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-32928346

RESUMO

OBJECTIVE: In order to investigate the effect of yeast on reducing mycotoxin damage in dried fish. METHODS: A strain of Meyerozyma guilliermondii MH 211588. 1(MG-81) was mixed and fermented 48 h with dried Lutjanus erythopterus which contaminated aflatoxin B_1(AFB_1) and T-2 toxin(T-2). The toxin concentration in fermentation at different time was detected by LC-MS/MS, and fermentation was fed with mice by intragastric administration(7 d). Blood routine and four liver function enzymes were measured by hematology analyzer and microplate spectrophotometer respectively. The elimination effect of MG-81 isolate on mycotoxin damage in dried fish was evaluated by the toxin concentration at different time and its toxic effect on mice. RESULTS: The removal rates of AFB_1 and T-2 in dried fish fermentation showed a parabolic linear growth trend with the prolongation of fermentation time. The removal rates of AFB_1 and T-2 in dried fish fermentation broth tended to be stable at 36 h(the removal rates of AFB_1 and T-2 were 83. 7%±1. 3% and 78. 5%±0. 8%). This indicated that 36 h was the optimal time for MG-81 to remove mycotoxins in dried fish. At the same time, it was found that there was no significant change in the indexes of MG-81 dried fish fermentation compared with the control group(P>0. 05), while the same dose of AFB_1 and T-2 dried fish fermentation(without MG-81), the leucocytes, lymphocytes, erythrocyte, hemoglobin, platelet and mean platelet volume of mice were significantly lower than those of control group(P>0. 05), showing obvious hemotoxicity and immunotoxicity. The activity of four liver enzymes was increased significantly(P<0. 05), showing obvious hepatotoxicity. CONCLUSION: The fermentation of MG-81 for 36 h can effectively remove AFB_1 and T-2 from dried fish and eliminate their hazards.


Assuntos
Saccharomycetales , Toxina T-2 , Aflatoxina B1/análise , Animais , Cromatografia Líquida , Camundongos , Espectrometria de Massas em Tandem
15.
Wei Sheng Yan Jiu ; 49(4): 591-602, 2020 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-32928350

RESUMO

OBJECTIVE: To establish an analytical method for determination of 6 kinds of α_2-agonists in animal foods by ultra high performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS). METHODS: The samples of animal food were enzymatic hydrolysis by ß-glucosidase/arylsulfatase, purified by MCX column. The separation was performed on a Dikma leapsil C_(18) column(2. 1 mm×100 mm, 2. 7 µm), then the target compound were detected by ultra high performance liquid chromatography-tandem mass spectrometry with electron spray ionization(ESI) positive ion scan in mode of multiple reaction monitoring(MRM) and quantified by matrix matched external standard method. RESULTS: At the spiked level of 1, 2 and 4 µg/kg, the recoveries of each compound were in the range of 70. 4%-111. 2% with the relative standard deviations of 2. 3%-18. 8%. The qualitative limits of detections were 0. 06-0. 3 µg/kg and the quantitative limits were 0. 2-1. 0 µg/kg for the 6 targets compounds. By using the established method, the target compound in 30 samples including pork, pig liver, pig kidney, beef and mutton were detected, and no excessive veterinary drug residue were detected. CONCLUSION: The established method is simple, rapid, high sensitivity and good stability, with a wide variety and a certain development. It can provide more convenient and fast detection method support for the daily monitoring of veterinary drug residues in animal food.


Assuntos
Resíduos de Drogas/análise , Espectrometria de Massas em Tandem , Animais , Bovinos , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Contaminação de Alimentos/análise , Suínos
16.
Wei Sheng Yan Jiu ; 49(4): 597-602, 2020 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-32928351

RESUMO

OBJECTIVE: To establish a method for analysis of 25-hydroxylvitamin D_2(25(OH)D_2), 25-hydroxylvitamin D_3(25(OH)D_3)and vitamin K_1 in serum by ultra-performance liquid chromatography tandem mass spectrometry(UPLC-MS/MS), which can be applied in diagnosis of vitamin deficiency and estimation on the nutritional status of people. METHODS: Serum samples mixed with d_6-25(OH)D_3, d_7-vitamin K_1(internal standard)were precipitated with acetonitrile and extracted with n-hexane. The sample solution was separated using BEH C_(18) column(2. 1 mm×100 mm, 1. 7 µm) with gradient elution using methanol-water containing 0. 1% formic acid as mobile phase. The target molecule was detected in positive electrospray ionization(ESI~+) and multiple reaction monitoring. RESULTS: The concentration of 25(OH)D_2, 25(OH)D_3 and vitamin K_1 showed good linearity in the range 5. 0-75. 0 ng/mL, 2. 0-81. 5 ng/mL and 0. 3-12. 0 ng/mL, respectively, with the correlation coefficients greater than 0. 995. The limits of detection(LOD) of 25(OH)D_2, 25(OH)D_3 and vitamin K_1 were 1, 0. 25 and 0. 1 ng/mL, and the limits of quantification(LOQ) for 25(OH)D_2, 25(OH)D_3 and vitamin K_1were 3, 0. 75 and 0. 3 ng/mL, respectively. The recoveries of three levels in the matrix were 98. 5%-104. 3%, the relative standard deviation(RSD) were all less than 5. 0%(n=6). CONCLUSION: An UPLC-MS/MS method for analysis of 25(OH)D_2, 25(OH)D_3 and vitamin K_1 in serum is sensitive, rapid, accurate and suitable for the nutritional surveillance of vitamin D and K_1 in the population.


Assuntos
Espectrometria de Massas em Tandem , Vitamina K 1 , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Vitamina D/análogos & derivados
17.
Chemosphere ; 258: 127367, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32947676

RESUMO

Due to their important roles in salt-producing acid-base reactions, new particle formation (NPF), and as precursors in secondary organic aerosol (SOA) producing reactions, the atmospheric concentrations of particulate volatile amines (dimethylamine (DMA), ethylamine, diethylamine (DEA), propylamine, and butylamine) at Seoul were analyzed and evaluated. To quantify the presence of volatile amines in particulate matter with aerodynamic diameters less than or equal to a nominal 2.5 µm (PM2.5), an efficient and rapid analytical method based on in-matrix ethyl chloroformate (ECF) derivatization followed by headspace solid-phase microextraction (HS-SPME) was developed and validated using gas chromatography coupled with tandem mass spectrometry (GC-MS/MS) in the multiple reaction monitoring (MRM) mode. The annual mean concentration of the total 5 target amines was 5.56±2.76 ng/m3 and the seasonal difference was small. The concentrations of particulate amines measured in this study were lower than those observed in Zongludak, Turkey, Nanjing, China, and Jeju, Korea but slightly higher than that reported in Kobe, Japan. The concentrations of the nitrosamines (nitrosodimethylamine (NDMA) and nitrosodiethylamine (NDEA)), and of the nitramines (dimethylnitramine (DMN) and diethylnitramine (DEN)) measured along with those of the target amines were used in a simple linear regression analysis. It indicates the contribution of DMA to the formation of NDMA in all seasons (except the fall) and DEA to the formation of NDEA in the summer, while DMA and DEA did not significantly contribute to the formation of nitramines.


Assuntos
Poluentes Atmosféricos/análise , Aminas/análise , Monitoramento Ambiental , China , Dietilnitrosamina , Dimetilaminas , Dimetilnitrosamina/análise , Etilaminas , Cromatografia Gasosa-Espectrometria de Massas/métodos , Nitrosaminas/análise , Material Particulado/análise , República da Coreia , Seul , Microextração em Fase Sólida/métodos , Espectrometria de Massas em Tandem
18.
Chemosphere ; 258: 127387, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32947680

RESUMO

It is well known that serum is an ideal and potential choice to reflect the toxicity of fluoride. However, the effects of fluoride on serum metabolome have not been reported until now. In this study, the models of 3-week-old rats exposed fluoride by breast milk and 11-week-old rats exposed fluoride via breast milk and drinking water containing sodium fluoride (100 mg/L) were established. Using Ultra Performance Liquid Chromatography-Mass Spectrometry/Mass Spectrometry (UPLC-MS/MS), as compared with control group, 28 negative (NEG) and 52 positive (POS) metabolites were significantly up-regulated, meanwhile 30 NEG and 21 POS significantly down-regulated metabolites were found in serum of 3-week-old rats exposed to fluoride. For 11-week-old fluorosis rats, there were 119 NEG and 65 POS metabolites significantly increased, and 7 NEG, 5 POS metabolites were obviously decreased. Importantly, nicotinamide, adenosine, 1-Oleoyl-sn-glycero-3-phosphocholine (OGPC), and 1-Stearoyl-sn-glycerol 3-phosphocholine (SGPC) were shared by two models. The metabolites of urea cycle, such as urea and N2-Acetyl-l-ornithine, betaine as a methyl donor, were regarded to reflect the fluorosis degree. These metabolites could be the potential markers of fluorosis, contributing to the prevention and treatment of fluorosis.


Assuntos
Fluoretos/toxicidade , Metaboloma/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Betaína , Cromatografia Líquida , Água Potável/química , Feminino , Humanos , Masculino , Metabolômica , Leite/metabolismo , Ratos , Fluoreto de Sódio , Espectrometria de Massas em Tandem
19.
Parasitol Res ; 119(9): 2837-2850, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32757109

RESUMO

Fasciola hepatica (F. hepatica) is a well-known zoonotic parasite that is crucial for economic and public health worldwide. Quantitative proteomics studies have been performed on proteins expressed by F. hepatica to investigate the differential expression of proteomes in different growth phases. And the screening of several marker proteins for use as early diagnostic antigens is essential. In this study, high-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) was conducted to analyze the differences in the expression of F. hepatica somatic proteins in different growth phases. Furthermore, gene ontology (GO) functional annotation, KEGG metabolic pathway, and clustering analyses were also performed. LC-MS/MS identified 629, 2286, 2254, and 2192 proteins in metacercariae, juvenile flukes 28dpi, immature flukes 59dpi, and adult phases, respectively. GO analysis revealed that differentially expressed proteins (DEPs) were mainly involved in transport, localization, metabolism, enzyme regulation, protein folding and binding, and nucleoside and nucleotide binding. The DEPs were enriched in cells, intracellular components, organelles, cytoplasm, vesicles, and membranes. KEGG pathway annotation results showed that the DEPs were involved in metabolism, genetic information processing, environmental information processing, cellular processes, organismal systems, and other processes. These findings provide a theoretical basis for vaccine development and establishing early diagnostic methods in the future.


Assuntos
Fasciola hepatica/crescimento & desenvolvimento , Fasciola hepatica/genética , Proteoma/análise , Animais , Cromatografia Líquida , Análise por Conglomerados , Biologia Computacional , Fasciolíase/parasitologia , Perfilação da Expressão Gênica , Proteoma/genética , Proteômica/métodos , Espectrometria de Massas em Tandem
20.
Sci Total Environ ; 745: 141036, 2020 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-32758732

RESUMO

Pesticide and veterinary drug residues are one of the stress factors affecting bee health and mortality. To investigate the occurrence, the concentration and the toxicity risk to bees of pesticide residues in four different types of beeswax (brood comb wax, recycled comb wax, honey comb wax, and cappings wax), 182 samples were collected from apiaries located all over the Belgian territories, during spring 2016 and analysed by LC-MS/MS and GC-MS/MS for the presence of 294 chemical residues. The toxicity risk to bees expressed as the Hazard Quotient (HQ) was calculated for each wax sample, according to two scenarios with different tau-fluvalinate LD50 values. Residues showing the highest prevalence were correlated to bee mortality in a multivariate logistic regression model and a risk-based model was used to predict colony bee mortality. Altogether, 54 different pesticide and veterinary drug residues were found in the four types of beeswax. The residues with a higher likelihood to be retained in beeswax are applied in-hive or with a high lipophilic nature. The multivariate logistic regression model showed a statistically significant influence of chlorfenvinphos on bee mortality. All our results indicated that cappings wax was substantially less contaminated. This national survey on beeswax contamination provides guidelines on the re-use of beeswax by beekeepers and shows the necessity to introduce maximum residue levels for global trade in beeswax. An online tool was developed to enable beekeepers and wax traders to estimate the risk to honey bee health associated with contaminated wax.


Assuntos
Resíduos de Praguicidas/análise , Resíduos de Praguicidas/toxicidade , Praguicidas/análise , Drogas Veterinárias , Animais , Abelhas , Bélgica , Cromatografia Líquida , Espectrometria de Massas em Tandem , Ceras
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