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1.
Wei Sheng Yan Jiu ; 50(1): 116-142, 2021 Jan.
Artículo en Chino | MEDLINE | ID: mdl-33517972

RESUMEN

OBJECTIVE: A method utilizing liquid chromatography-tandem mass spectrometry(LC-MS/MS) coupled with dispersive solid phase extraction for quantitative analysis of domoic acid in four kinds of shellfish was established. METHODS: The sample of 0. 1 g was extracted with 25% methanol aqueous solution, the extract was purified by dispersive solid phase extraction with 50 mg HLB and 5 mg GCB, and then filtered through a PTFE membrane. The analytes were separated on a C_(18) column(100 mm×2. 1 mm, 1. 9 µm), and detected in selected reaction monitoring(SRM) mode via positive electrospray ionization. The matrix matching and external standard method was used for quantitation. RESULTS: Domoic acid showed good linearity in the concentration range between 1. 0 ng/mL and 50. 0 ng/mL with correlation coefficients higher than 0. 9994. The detection limits of domoic acid in shellfish was 5 µg/kg. The inter-and intra-day recoveries were 91. 6%-109. 2% and 90. 9%-109. 3%, respectively. The inter-and intra-day ralitive standard deviations(RSDs) were lower than 8. 2% at spiked concentrations of 20, 50 and 100 µg/kg. CONCLUSION: The method is accurate, fast, easy to operate, which can satisfy the requirements of public health emergency testing or routine testing.


Asunto(s)
Extracción en Fase Sólida , Espectrometría de Masas en Tándem , Cromatografía Líquida de Alta Presión , Cromatografía Liquida , Ácido Kaínico/análogos & derivados , Mariscos/análisis
2.
Wei Sheng Yan Jiu ; 50(1): 121-128, 2021 Jan.
Artículo en Chino | MEDLINE | ID: mdl-33517973

RESUMEN

OBEJECTIVE: To develop a method for the determination of 13 antibiotics in 8 classes for desinfection products by ulta-high perfomance chromatography-tandem mass spectrometry(UPLC-MS/MS). METHODS: Samples were extracted by methanol or acetonitrile. The target compouds were separated on a Waters HSS T3 column(100 mm×2. 1 mm, 1. 8 µm), and detected by triple quadrupole tandem mass spectrometer. RESULTS: The 13 selected antibiotics showed good linear relationships in the range of 4-100 µg/L and the correlation coefficients(r~2) were all above 0. 991. The limits of detection ranged from 2 to 25 µg/kg. The recovery rates at three spiked levels(low, medium and high) in three dosage forms of disinfection products were in the range of 71. 2%-130. 4%, and the relative standard deviations(RSD) were all less than 11. 3%, which could meet the detection requirements of illegal addition of antibiotics in disinfection products. Ofloxacin at a concentration of 21. 1 mg/kg was found in a cream disinfection product by the developed method, and no related drugs were detected in other samples. CONCLUSION: This method is simple, reliable, reproducible, which covers a wide range of antibiotics, and provides technical support for monitoring the illegal addition of antibiotics in disinfection products.


Asunto(s)
Antibacterianos , Espectrometría de Masas en Tándem , Cromatografía Líquida de Alta Presión , Cromatografía Liquida , Desinfección
3.
Sci Rep ; 11(1): 3061, 2021 02 04.
Artículo en Inglés | MEDLINE | ID: mdl-33542252

RESUMEN

The outbreak of COVID-19 has raised interest in the kinin-kallikrein system. Viral blockade of the angiotensin-converting enzyme 2 impedes degradation of the active kinin des-Arg(9)-bradykinin, which thus increasingly activates bradykinin receptors known to promote inflammation, cough, and edema-symptoms that are commonly observed in COVID-19. However, lean and reliable investigation of the postulated alterations is currently hindered by non-specific peptide adsorption, lacking sensitivity, and cross-reactivity of applicable assays. Here, an LC-MS/MS method was established to determine the following kinins in respiratory lavage fluids: kallidin, bradykinin, des-Arg(10)-kallidin, des-Arg(9)-bradykinin, bradykinin 1-7, bradykinin 2-9 and bradykinin 1-5. This method was fully validated according to regulatory bioanalytical guidelines of the European Medicine Agency and the US Food and Drug Administration and has a broad calibration curve range (up to a factor of 103), encompassing low quantification limits of 4.4-22.8 pg/mL (depending on the individual kinin). The application of the developed LC-MS/MS method to nasal lavage fluid allowed for the rapid (~ 2 h), comprehensive and low-volume (100 µL) determination of kinins. Hence, this novel assay may support current efforts to investigate the pathophysiology of COVID-19, but can also be extended to other diseases.


Asunto(s)
Bradiquinina/análisis , Sistema Calicreína-Quinina , Líquido del Lavado Nasal/química , Adulto , Cromatografía Liquida , Femenino , Voluntarios Sanos , Humanos , Masculino , Espectrometría de Masas en Tándem , Adulto Joven
4.
Nat Commun ; 12(1): 1020, 2021 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-33589611

RESUMEN

The extracellular matrix (ECM) is unique to each tissue and capable of guiding cell differentiation, migration, morphology, and function. The ECM proteome of different developmental stages has not been systematically studied in the human pancreas. In this study, we apply mass spectrometry-based quantitative proteomics strategies using N,N-dimethyl leucine isobaric tags to delineate proteome-wide and ECM-specific alterations in four age groups: fetal (18-20 weeks gestation), juvenile (5-16 years old), young adults (21-29 years old) and older adults (50-61 years old). We identify 3,523 proteins including 185 ECM proteins and quantify 117 of them. We detect previously unknown proteome and matrisome features during pancreas development and maturation. We also visualize specific ECM proteins of interest using immunofluorescent staining and investigate changes in ECM localization within islet or acinar compartments. This comprehensive proteomics analysis contributes to an improved understanding of the critical roles that ECM plays throughout human pancreas development and maturation.


Asunto(s)
Proteínas de la Matriz Extracelular/genética , Regulación del Desarrollo de la Expresión Génica , Páncreas/metabolismo , Proteoma/genética , Adolescente , Adulto , Niño , Preescolar , Cromatografía Liquida , Matriz Extracelular/genética , Matriz Extracelular/metabolismo , Proteínas de la Matriz Extracelular/clasificación , Proteínas de la Matriz Extracelular/metabolismo , Femenino , Feto , Técnica del Anticuerpo Fluorescente , Ontología de Genes , Humanos , Masculino , Persona de Mediana Edad , Anotación de Secuencia Molecular , Organogénesis/genética , Páncreas/crecimiento & desarrollo , Proteoma/clasificación , Proteoma/metabolismo , Proteómica/métodos , Espectrometría de Masas en Tándem
5.
Environ Monit Assess ; 192(Suppl 1): 812, 2021 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-33443728

RESUMEN

An analytical method was developed by using LC-ESI(-ve)-MS/MS to investigate the residue dynamics of 2,4-D (2,4-dichlorophenoxyacetic acid) in green tea leaves, processed tea, tea liquor, and tea-cropped soil at Singhiajhora Tea Estate and Putinbari Tea Estate at Terai Region, Darjeeling District, West Bengal, India. In this method, an acidified methanol was used for extraction and subsequent clean-up was done by HLB (hydrophilic lipophilic balanced) cartridges. The method was validated as per SANTE guideline (SANTE/11813/2017). The limit of quantification (LOQ) of 2,4-D was 0.05 mgkg-1 and average % recoveries were in the range from 88.05 to 113.28 with relative standard deviation (RSD) 3.46 to 6.43. The dissipation of 2,4-D followed the 1st-order reaction kinetics with a half-life (T1/2) of 1.51-1.61 day at the recommended dose and 2.50-2.72 day for doubled recommended dose in tea for both locations. This method can be applied successfully for the determination of 2,4 D residues in/on tea matrix and subsequent studies on safety evaluation showed that the use of 2,4-D in tea is safe.


Asunto(s)
Camellia sinensis , Residuos de Plaguicidas , Ácido 2,4-Diclorofenoxiacético , Cromatografía Liquida , Monitoreo del Ambiente , India , Residuos de Plaguicidas/análisis , Espectrometría de Masas en Tándem ,
6.
BMC Infect Dis ; 21(1): 99, 2021 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-33482745

RESUMEN

BACKGROUND: Treatment monitoring of drug-resistant tuberculosis (DR-TB) in resource-limited settings is challenging. We developed a multi-analyte assay for eleven anti-TB drugs in small hair samples as an objective metric of drug exposure. METHODS: Small hair samples were collected from participants at various timepoints during directly observed RR-TB treatment at an inpatient tertiary referral facility in South Africa (DR-TB cohort). We assessed qualitative determination (i.e., detection above limit of detection) of bedaquiline, linezolid, clofazimine, pretomanid, levofloxacin, moxifloxacin, pyrazinamide, isoniazid, ethambutol, ethionamide, and prothionamide in an LC-MS/MS index panel assay against a reference standard of inpatient treatment records. Because treatment regimens prior to hospitalization were not available, we also analyzed specificity (for all drugs except isoniazid) using an external cohort of HIV-positive patients treated for latent TB infection with daily isoniazid (HIV/LTBI cohort) in Uganda. RESULTS: Among the 57 DR-TB patients (58% with pre-XDR/XDR-TB; 70% HIV-positive) contributing analyzable hair samples, the sensitivity of the investigational assay was 94% or higher for all drugs except ethionamide (58.5, 95% confidence interval [CI], 40.7-99.9). Assay specificity was low across all tested analytes within the DR-TB cohort; conversely, assay specificity was 100% for all drugs in the HIV/LTBI cohort. CONCLUSIONS: Hair drug concentrations reflect long-term exposure, and multiple successive regimens commonly employed in DR-TB treatment may result in apparent false-positive qualitative and falsely elevated quantitative hair drug levels when prior treatment histories within the hair growth window are not known.


Asunto(s)
Antituberculosos/análisis , Monitoreo de Drogas/métodos , Cabello/química , Rifampin/farmacología , Tuberculosis Resistente a Múltiples Medicamentos/tratamiento farmacológico , Adulto , Antituberculosos/uso terapéutico , Cromatografía Liquida , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mycobacterium tuberculosis/efectos de los fármacos , Sensibilidad y Especificidad , Espectrometría de Masas en Tándem , Tuberculosis/tratamiento farmacológico
7.
Sci Rep ; 11(1): 2291, 2021 01 27.
Artículo en Inglés | MEDLINE | ID: mdl-33504824

RESUMEN

Coronavirus disease 2019 (COVID-19) pandemic is affecting millions of patients worldwide. The consequences of initial exposure to SARS-CoV-2 go beyond pulmonary damage, with a particular impact on lipid metabolism. Decreased levels in HDL-C were reported in COVID-19 patients. Since HDL particles display antioxidant, anti-inflammatory and potential anti-infectious properties, we aimed at characterizing HDL proteome and functionality during COVID-19 relative to healthy subjects. HDLs were isolated from plasma of 8 severe COVID-19 patients sampled at admission to intensive care unit (Day 1, D1) at D3 and D7, and from 16 sex- and age-matched healthy subjects. Proteomic analysis was performed by LC-MS/MS. The relative amounts of proteins identified in HDLs were compared between COVID-19 and controls. apolipoprotein A-I and paraoxonase 1 were confirmed by Western-blot analysis to be less abundant in COVID-19 versus controls, whereas serum amyloid A and alpha-1 antitrypsin were higher. HDLs from patients were less protective in endothelial cells stiumalted by TNFα (permeability, VE-cadherin disorganization and apoptosis). In these conditions, HDL inhibition of apoptosis was blunted in COVID-19 relative to controls. In conclusion, we show major changes in HDL proteome and decreased functionality in severe COVID-19 patients.


Asunto(s)
/sangre , Lipoproteínas HDL/sangre , Apolipoproteína A-I/sangre , Arildialquilfosfatasa/análisis , Arildialquilfosfatasa/sangre , /patología , Estudios de Casos y Controles , Cromatografía Liquida/métodos , Células Endoteliales/patología , Femenino , Francia/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Pandemias , Proteoma/metabolismo , Proteómica/métodos , Proteína Amiloide A Sérica/metabolismo , Espectrometría de Masas en Tándem/métodos , Factor de Necrosis Tumoral alfa/sangre , alfa 1-Antitripsina/sangre
8.
J Chromatogr A ; 1637: 461733, 2021 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-33385745

RESUMEN

A hydrophilic interaction (HILIC) ultra-high performance liquid chromatography (UHPLC) with triple quadrupole tandem mass spectrometry (MS/MS) method was developed and validated for the quantification of 21 free amino acids (AAs). Compared to published reports, our method renders collectively improved sensitivity with lower limit of quantification (LLOQ) at 0.5~42.19 ng/mL with 0.3 µL injection volume (or equivalently 0.15~12.6 pg injected on column), robust linear range from LLOQ up to 3521~5720 ng/mL (or 1056 ~ 1716 pg on column) and a high throughput with total time of 6 min per sample, as well as easier experimental setup, less maintenance and higher adaptation flexibility. Ammonium formate in the mobile phase, though commonly used in HILIC, was found unnecessary in our experimental setup, and its removal from mobile phase was key for significant improvement in sensitivity (4~74 times higher than with 5 mM ammonium formate). Addition of 10 (or up to100 mM) hydrochloric acid (HCl) in the sample diluent was crucial to keep response linearity for basic amino acids of histidine, lysine and arginine. Different HCl concentration (10~100 mM) in sample diluent also excreted an effect on detection sensitivity, and it is of importance to keep the final prepared sample and calibrators in the same HCl level. Leucine and isoleucine were distinguished using different transitions. Validated at seven concentration levels, accuracy was bound within 75~125%, matrix effect generally within 90~110%, and precision error mostly below 2.5%. Using this newly developed method, the free amino acids were then quantified in a total of 544 African indigenous vegetables (AIVs) samples from African nightshades (AN), Ethiopian mustards (EM), amaranths (AM) and spider plants (SP), comprising a total of 8 identified species and 43 accessions, cultivated and harvested in USA, Kenya and Tanzania over several years, 2013~2018. The AN, EM, AM and SP were distinguished based on free AAs profile using machine learning methods (ML) including principle component analysis, discriminant analysis, naïve Bayes, elastic net-regularized logistic regression, random forest and support vector machine, with prediction accuracy achieved at ca. 83~97% on the test set (train/test ratio at 7/3). An interactive ML platform was constructed using R Shiny at https://boyuan.shinyapps.io/AIV_Classifier/ for modeling train-test simulation and category prediction of unknown AIV sample(s). This new method presents a robust and rapid approach to quantifying free amino acids in plants for use in evaluating plants, biofortification, botanical authentication, safety, adulteration and with applications to nutrition, health and food product development.


Asunto(s)
Aminoácidos/análisis , Cromatografía Líquida de Alta Presión/métodos , Aprendizaje Automático , Espectrometría de Masas en Tándem/métodos , Verduras/química , Teorema de Bayes , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Análisis de Componente Principal , Reproducibilidad de los Resultados
9.
J Chromatogr A ; 1637: 461836, 2021 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-33422795

RESUMEN

The interest in the therapeutic values of natural compounds from plants is growing worldwide because the development of modern synthetic drugs has not lived up to expectations. The tree Ficus religiosa native to India, China and Southeast Asia is traditionally used for curing almost 50 ailments, although the majority of the individual active compounds are not known. Hence, a hyphenated high-performance thin-layer chromatography (HPTLC) method was newly developed. It allowed a physicochemical, but especially effect-directed profiling of individual compounds present in Ficus religiosa leaves obtained from four locations (in India and Germany). Extracts of different polarities were screened for bioactivity responses and most bioactivities were found in the ethyl acetate extracts. A multi-imaging via 26 different detection modes was performed, i. e. UV/Vis/FLD, 11 microchemical derivatizations and 12 effect-directed assays (EDA). By HPTLC-UV/Vis/FLD-EDA, antibiotics against Gram-positive and Gram-negative bacteria as well as acetylcholinesterase, butyrylcholinesterase, tyrosinase, α-amylase, α-glucosidase and ß-glucosidase inhibitors and radical scavenging compounds were detected. Estrogen-like or gentotoxic compounds were not detected at higher extract amounts of even 5 mg/band applied. For further characterization of three most important, multipotent, bioactive compound zones, HPTLC was hyphenated with heated electrospray ionization high-resolution mass spectrometry including fragmentation (HPTLC-HESI-HRMS/MS). Multipotent bioactive compounds discovered in the extracts were equivalently calculated in reference to well-known reference inhibitors.


Asunto(s)
Antibacterianos/aislamiento & purificación , Ficus/química , Extractos Vegetales/farmacología , Hojas de la Planta/química , Antibacterianos/farmacología , Cromatografía en Capa Delgada/métodos , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Espectrometría de Masa por Ionización de Electrospray/métodos , Espectrometría de Masas en Tándem/métodos
10.
Food Chem ; 346: 128898, 2021 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-33453579

RESUMEN

In 2016, the European Commission recommended the Member States to monitor the content of Δ9-tetrahydrocannabinol and other cannabinoids in food and feed derived from hemp and in food of animal origin for possible transfer from feed. Thus, the Italian Ministry of Health implemented a monitoring plan. To this aim, nine cannabinoids in beverages and food for human consumption and in feed were determined. The method applied, based on rapid clean-up and LC-MS/MS determination, was previously developed and in-house validated, evaluating the analytical performance in the concentration ranges 2-50 µg/L for beverages, 0.020-0.500 mg/kg for food and 0.100-10.0 mg/kg for feed. Then, it was applied to determine the cannabinoids in 78 food, 16 beverage and 6 feed samples, collected from the Italian market since 2017. The results are herein reported, for evaluation of both product characteristics and compliance to national maximum limits. Some study cases are also described.


Asunto(s)
Alimentación Animal/análisis , Bebidas/análisis , Cromatografía Liquida , Dronabinol/análisis , Análisis de los Alimentos/métodos , Espectrometría de Masas en Tándem , Animales , Cannabis/química , Humanos , Italia
11.
Sci Total Environ ; 764: 143963, 2021 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-33385644

RESUMEN

Consumption of licit and/or illicit compounds during sporting events has traditionally been monitored using population surveys, medical records, and law enforcement seizure data. This pilot study evaluated the temporal and geospatial patterns in drug consumption during a university football game from wastewater using liquid chromatography tandem mass spectrometry (LC-MS/MS). Untreated wastewater samples were collected from three locations within or near the same football stadium every 30 min during a university football game. This analysis leveraged two LCMS/ MS instruments (Waters Acquity TQD and a Shimadzu 8040) to analyze samples for 58 licit or illicit compounds and some of their metabolites. Bayesian multilevel models were implemented to estimate mass load and population-level drug consumption, while accounting for multiple instrument runs and concentrations censored at the lower limit of quantitation. Overall, 29 compounds were detected in at least one wastewater sample collected during the game. The 10 most common compounds included opioids, anorectics, stimulants, and decongestants. For compounds detected in more than 50% of samples, temporal trends in median mass load were correlated with the timing of the game; peak loads for cocaine and tramadol occurred during the first quarter of the game and for phentermine during the third quarter. Stadium-wide estimates of the number of doses of drugs consumed were rank ordered as follows: oxycodone (n = 3246) > hydrocodone (n = 2260) > phentermine (n = 513) > cocaine (n = 415) > amphetamine (n = 372) > tramadol (n = 360) > pseudoephedrine (n = 324). This analysis represents the most comprehensive assessment of drug consumption during a university football game and indicates that wastewater-based epidemiology has potential to inform public health interventions focused on reducing recreational drug consumption during large-scale sporting events.


Asunto(s)
Aguas Residuales , Contaminantes Químicos del Agua , Teorema de Bayes , Cromatografía Liquida , Humanos , Proyectos Piloto , Detección de Abuso de Sustancias , Espectrometría de Masas en Tándem , Universidades , Aguas Residuales/análisis , Contaminantes Químicos del Agua/análisis
12.
Environ Pollut ; 271: 116406, 2021 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-33412445

RESUMEN

As an emerging brominated flame retardant (BFR), tetrabromobisphenol S (TBBPS) has been frequently detected in the environmental media and organisms. Knowledges on the transformation and fate of TBBPS in both environment and engineering systems are essential to its ecological risk assessment. Herein, we reported the photochemical decomposition of TBBPS in aqueous solution upon 254 nm ultraviolet irradiation (UV254). Results show that TBBPS was highly photoreactive, most likely due to the presence of four ortho-bromine substituents. The molar absorption coefficient and quantum yield of TBBPS were found to be pH-dependent, with the monoanionic form being most photoreactive. A series of photoproducts were identified by solid phase extraction (SPE) combined with liquid chromatography-electrospray ionization-triple quadrupole mass spectrometry (LC-ESI(+)-MS/MS. The photolysis of TBBPS likely proceeded through photonucleophilic substitution, photoreductive debromination, and ß-scission reactions. A ketocarbene, possibly derived from the lower lying excited triplet state, was proposed to be involved in the photolysis of TBBPS. Ion chromatography analysis revealed that debromination occurred quickly, and the yield of bromide (Br-) approached 100% after 90 min irradiation. The presence of SRNOM and MRNOM inhibited the photodegradation rate of TBBPS, which is likely due to the light-screening and physical quenching effects of natural organic matter (NOM). Our results reveal that photolysis is an important process for the attenuation of TBBPS in aquatic system; however, naturally occurring species such as NOM can appreciably retard the decay of TBBPS.


Asunto(s)
Retardadores de Llama , Bifenilos Polibrominados , Fotólisis , Espectrometría de Masas en Tándem
13.
Sheng Wu Gong Cheng Xue Bao ; 37(1): 276-289, 2021 Jan 25.
Artículo en Chino | MEDLINE | ID: mdl-33501808

RESUMEN

Different microorganisms can cause intraperitoneal infection. This study was to distinguish different microbial infections by urine analysis. Rats were intraperitoneally injected with Escherichia coli, Staphylococcus aureus, and Candida albicans, separately. Urine samples were collected from rats at 0, 12, 36 and 72 h after infection. Urinary proteins were profiled using liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). Compared with the control (without infection), a total of 69 differential proteins were identified in rats injected with E. coli. A total of 31 differences proteins were identified in rats injected with S. aureus. A total of 38 differential proteins were identified in rats injected with C. albicans. Urine proteome was different when rats were infected by different microorganisms, suggesting that urine may have the potential for differential diagnosis of different intraperitoneal infections.


Asunto(s)
Proteoma , Espectrometría de Masas en Tándem , Animales , Cromatografía Liquida , Escherichia coli , Ratas , Staphylococcus aureus
14.
Water Res ; 190: 116752, 2021 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-33385875

RESUMEN

The occurrence and removal patterns of 24 antimicrobial agents and antimicrobial resistant determinants namely 6 antibiotic resistance genes (ARGs) and 2 mobile genetic elements (MGEs), and the fecal indicator E. coli were investigated in three full-scale wastewater treatment plants. Their waterlines and biosolids lines (including secondary treatment based on both granular and activated sludge) were sampled monthly throughout one year. Samples were analyzed by means of LC-MS/MS, qPCR and cell enumeration, respectively. The influence of rainfall, temperature, and turbidity on the occurrence and removal of the aforementioned agents was assessed through statistical linear mixed models. Ten of the antimicrobial agents (macrolides, fluoroquinolones, tetracyclines, and sulfonamides) were commonly found in influent in concentrations of 0.1-2 µg L-1, and the predominant ARGs were ermB and sul1 (6.4 and 5.9 log10 mL-1 respectively). Warmer temperatures slightly reduced gene concentrations in influent whilst increasing that of E. coli and produced an uneven effect on the antimicrobial concentrations across plants. Rainfall diluted both E. coli (-0.25 logs, p < 0.001) and antimicrobials but not genes. The wastewater treatment reduced the absolute abundance of both genes (1.86 logs on average) and E. coli (2.31 logs on average). The antimicrobials agents were also partly removed, but 8 of them were still detectable after treatment, and 6 accumulated in the biosolids. ARGs were also found in biosolids with patterns resembling those of influent. No significant differences in the removal of antimicrobials, genes and E. coli were observed when comparing conventional activated sludge with aerobic granular sludge. Irrespective of the type of sludge treatment, the removal of genes was significantly reduced with increasing hydraulic loads caused by rainfall (-0.35 logs per ∆ average daily flow p < 0.01), and slightly decreased with increasing turbidity (-0.02 logs per ∆1 nephelometric turbidy unit p < 0.05) .


Asunto(s)
Genes Bacterianos , Aguas del Alcantarillado , Antibacterianos , Cromatografía Liquida , Escherichia coli/genética , Espectrometría de Masas en Tándem , Eliminación de Residuos Líquidos , Aguas Residuales
15.
Ecotoxicol Environ Saf ; 210: 111853, 2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-33422838

RESUMEN

A multi-residue analysis of six diacylhydrazine insecticides in water, sediment, and aquatic products was established by liquid chromatography triple quadrupole tandem mass spectrometry (LC-MS/MS). The water sample was extracted with acetonitrile by low-temperature enrichment liquid-liquid extraction technology. The sediment and aquatic products were prepared using QuEChERS technique. Method validation showed perfect linearity with correlation coefficients (R) more than 0.9992 for all insecticides, and the matrix effects were nearly negligible (-1.42% to -0.27%) for water, sediment and aquatic products. The recoveries were 80.0-99.7% at three spiked levels (0.02 ng·mL-1, 0.1 ng·mL-1, 0.5 ng·mL-1; 2.0, 10, and 50 ng·g-1) and the precisions (intra-day and inter-day precision) were lower than 5.28%, with the low LODs (3.8 ~ 9.6 pg·mL-1; 0.38-0.96 ng·g-1) and LOQs (12.7 ~ 32.0 pg·mL-1; 1.27-3.20 ng·g-1) for water, sediment, and aquatic products, indicating the good accuracy and precision of the proposed method. The applicability, efficiency, and sensitivity of this method have been proved in the analysis of six diacylhydrazine insecticides in water, sediment, and crucian carp in Rice- crucian carp - integrated planting system.


Asunto(s)
Hidrazinas/análisis , Insecticidas/análisis , Contaminantes Químicos del Agua/análisis , Animales , Carpas , Cromatografía Líquida de Alta Presión/métodos , Monitoreo del Ambiente , Sedimentos Geológicos/análisis , Límite de Detección , Oryza , Espectrometría de Masa por Ionización de Electrospray , Espectrometría de Masas en Tándem/métodos
16.
Ecotoxicol Environ Saf ; 211: 111908, 2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-33440265

RESUMEN

Hexavalent chromium [Cr(VI)] is a common heavy metal pollutant that can cause a number of human disease, including inflammation and cancer. Senescent cells can secrete a variety of molecules known as senescence-associated secretory phenotype (SASP). Our previous studies have confirmed that Cr(VI) can induce premature senescence in L02 hepatocytes, but the composition and the function of the related SASP are still unknown. In order to understand the components of SASP secreted by senescent L02 hepatocytes under the action of Cr(VI), we applied LC-MS/MS-based label-free protein quantification. We found that three SASP components including Coactosin-like protein 1 (COTL1), Alpha-enolase (ENO1), and Peroxiredoxin 2 (PRDX2) were up-regulated, which were confirmed by western blotting and qRT-PCR. Evidence suggested that SASP may promote the development of tumor through chronic inflammatory response, therefore we identified and analyzed the potential biological functions and signaling pathways of these three SASP components using GO and KEGG methods. The interaction between SASP components was analyzed by STRING, and verified by Co-IP. We also found that ENO1 and PRDX2, which have direct interaction, can inhibit the growth and proliferation of wildtype hepatocytes and premature senescent hepatocytes, but can promote the proliferation and behavioral changes of liver tumor cells. The present study provides valuable clues for elucidation of the carcinogenic mechanism of Cr(VI), especially for further prevention and targeted treatment of Cr(VI)-related cancer.


Asunto(s)
Senescencia Celular , Cromo/toxicidad , Línea Celular , Cromatografía Liquida , Hepatocitos/metabolismo , Humanos , Proteínas de Microfilamentos/metabolismo , Fenotipo , Transducción de Señal , Espectrometría de Masas en Tándem , Regulación hacia Arriba
17.
Water Res ; 192: 116833, 2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-33486287

RESUMEN

Pharmaceutically active compounds (PhACs) widely present in urban wastewater effluents pose a threat to ecosystems in the receiving aquatic environment. In this work, efficiency of granular activated carbon (GAC) - based catalytic processes, namely catalytic wet peroxide oxidation (CWPO), peroxymonosulfate oxidation (PMS/GAC) and peroxydisulfate oxidation (PDS/GAC) at ambient temperature and pressure were studied for removal of 22 PhACs (ng L-1 level) that were present in secondary effluents of real urban wastewater. Concentrations of PhACs were measured using Ultra Performance Liquid Chromatography - Triple Quadrupole Mass Spectrometry (UPLC-QqQ-MS/MS). Catalytic experiments were conducted in discontinuous mode using up-flow fixed bed reactors with granular activated carbon (GAC) as a catalyst. The catalyst was characterized by means of N2 adsorption-desorption isotherm, mercury intrusion porosimetry (MIP), elemental analysis, X-ray fluorescence spectroscopy (WDXRF), X-ray diffraction (XRD), thermal gravimetry and differential temperature analyses coupled mass spectrometry (TGA-DTA-MS). Results indicate that the highest efficiency in terms of TOC removal was achieved during CWPO performed at optimal operational conditions (stoichiometric dose of H2O2; TOC removal ~ 82%) followed by PMS/GAC (initial PMS concentration 100 mg L-1; TOC removal ~73.7%) and PDS/GAC (initial PDS concentration 100 mg L-1; TOC removal ~ 67.9%) after 5 min of contact time. Full consumption of oxidants was observed in all cases for CWPO and PDS/GAC at contact times of 2.5 min, while for PMS/GAC it was 1.5 min. In general, for 18 out of 22 target PhACs, very high removal efficiencies (> 92%) were achieved in all tested processes (including adsorption) performed at optimal operational conditions during 5 min of contact time. However, moderate (40 - 70%) and poor (< 40%) removal efficiencies were achieved for salicylic acid, ofloxacin, norfloxacin and ciprofloxacin, which can be possibly attributed to insufficient contact time. Despite high efficiency of all studied processes for PhACs elimination from urban wastewater effluent, CWPO seems to be more promising for continuous operation.


Asunto(s)
Contaminantes Químicos del Agua , Purificación del Agua , Adsorción , Carbón Orgánico , Ecosistema , Peróxido de Hidrógeno , Espectrometría de Masas en Tándem , Eliminación de Residuos Líquidos , Aguas Residuales , Contaminantes Químicos del Agua/análisis
18.
Water Res ; 192: 116835, 2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-33486289

RESUMEN

The complexity of production process and chemical compositions of soluble microbial products (SMPs) largely limits the understanding of membrane fouling in membrane bioreactors (MBRs). Herein, we used a model single-strain Escherichia coli to better understand the chemical natures of SMPs and their roles in membrane fouling. The effects of carbon source and growth phase on the chemical compositions of SMPs were identified at both the compound and molecular levels by using advanced techniques including excitation emission matrix and parallel factor analysis (EEM-PARAFAC), size exclusion chromatography coupled with organic carbon detection (LC-OCD), and untargeted ultra-performance liquid chromatography - Q-Exactive - mass spectrometry (UPLC-Q-Exactive-MS). Subsequently, the roles of SMPs in the propensity of membrane fouling during ultrafiltration (UF) were studied. The results showed that the chemical compositions and fouling potentials of SMPs were carbon source- and growth phase-dependent. In the exponential phase, SMPs mainly consisted of utilization-associated products (UAPs) and remaining substrates. As the microorganism progressed into the stationary and senescent phases, UAPs and biomass-associated products (BAPs) were the main components, respectively. The SMP contents generated in glucose medium were higher than those generated in acetate medium, and higher abundances of humic fluorescent components were observed in glucose-fed SMPs. Van Krevelen diagrams of the UPLC-MS results revealed that acetate-fed SMPs contained more carboxylic-rich alicyclic molecules, peptides-like, aromatic, and carbohydrates-like components than glucose-fed SMPs in the stationary and senescent phases. These components played a significant role in irreversible membrane fouling, as evidenced in UF experiments. Standard blocking and cake filtration were the main fouling mechanisms for the filtration of SMPs collected in the exponential and stationary/senescent phases, respectively. Our findings highlight linkages between SMP compositions and membrane fouling at both the compound and molecular levels and suggest that both the carbon source and growth phase strongly determine the production potential, chemical nature, and fouling behavior of SMPs.


Asunto(s)
Membranas Artificiales , Aguas del Alcantarillado , Reactores Biológicos , Cromatografía Liquida , Escherichia coli , Espectrometría de Masas en Tándem
19.
J Chromatogr A ; 1638: 461867, 2021 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-33485029

RESUMEN

Considering that neurotransmitters (NTs) and amino acids (AAs) exert pivotal roles in various neurological diseases, global detection of these endogenous metabolites is of great significance for the treatment of nervous system diseases. Herein, a workflow that could cope with various challenges was proposed to establish an extendable all-in-one injection liquid chromatography-tandem mass spectrometry (LC-MS/MS) assay for analyzing these small molecular metabolites with high coverage. To obtain a qualified blank biological matrix for the preparation of standard curves and quality control samples, different absorption solvents, including activated carbon (AC), calcite (Cal) and montmorillonite (Mnt) were systematically evaluated for efficient absorption of endogenous substances with minimum residue. We also firstly proposed a "Collision Energy Defect (CED)" strategy to solve the huge difference of mass signal strength caused by different properties and concentrations of 11 NTs and 17 AAs. The quantitative results were validated by LC-MS/MS. Sensitivity, accuracy, and recovery meeting generally accepted bioanalytic guidelines were observed in a concentration span of at least 100 to 500 times for each analyte. Then the temporal changes of intracerebral and peripheral NTs and AAs in ischemic stroke model and sham operated rats were successfully produced and compared using the described method. All these results suggested that the currently developed assay was powerful enough to simultaneously monitor a large panel of endogenous small molecule metabolites, which was expected to be widely used in the research of various diseases mediated by NTs and AAs.


Asunto(s)
Aminoácidos/química , Cromatografía Liquida , Neurotransmisores/química , Espectrometría de Masas en Tándem , Adsorción , Animales , Masculino , Ratas
20.
Phytochemistry ; 183: 112643, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33421889

RESUMEN

Phytochelatins (PCs) are peptides that play an important role in homeostasis and detoxification of heavy metal in plants. Furthermore, they have been proposed as earlier potential biomarkers of aquatic pollution by heavy metals. Nowadays, several researchers have reported on current methods for quantification of glutathione (GSH) and the PCs (phytochelatin 2, phytochelatin 3, phytochelatin 4) quantification in plants. However, no method has reported the uncertainty of the measurement, which helps to improve the accuracy and quality assurance in the PC quantification. In this work, a new methodology using ultra-high-performance liquid chromatography coupled to mass spectrometry (UPLC-MS) to measure with high precision and accuracy the PCs in aquatic plants, was validated. Selectivity, linearity, limit of detection, limit of quantification, precision, trueness and uncertainty estimation were examined as parts of the method validation. The described method shows excellent linearity in different ranges for all analytes with coefficients of determination higher than 0.99. The relative standard deviation for intra-day precision was <3% and for inter-day <10%. All LOD and LOQ analytes ranged from 0.02 to 0.08 µg ml-1, and from 0.03 to 0.09 µg ml-1, respectively. The recoveries varied from 61% to 89%. In order to obtain an interval of results with the highest confidence levels, the uncertainty associated with the measurements was evaluated. The calibration curve (>50%) and recovery (19-44%) were the most important contributors to the total uncertainty. The proposed method was applied to quantify GSH and PCs in the aquatic plants Lemna gibba L., Myriophyllum heterophyllum Michx., Arenaria paludicola and Hydrocotyle ranunculoides L. fil., showing statistical differences in the mass fraction of the analytes.


Asunto(s)
Fitoquelatinas , Espectrometría de Masas en Tándem , Cromatografía Líquida de Alta Presión , Cromatografía Liquida , Incertidumbre
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