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OBJECTIVE: To develop a method which is used for rapid determination of 16 kinds of polycyclic aromatic hydrocarbons(PAHs) and 16 kinds of phthalates(PAEs) in tap water by stirring rod adsorption extraction(SBSE) combined with gas chromatography-mass spectrometry(GC-MS). METHODS: The twister mixing rod coated with polydimethylsiloxane(PDMS) and ethylene glycol-polydimethylsiloxane(EG-silicone) was used to enrich analyte from 50 mL tap water. The twister mixing rod coated with EG-silicone was directly placed into the sample bottle containing 50 mL of tap water, while fixing the PDMS stir bar on the inner wall of the sample bottle and immersing it in the liquid. Add 5%(W/V) sodium chloride to the sample bottle, followed by adding 5% methanol. Stir at room temperature for 2 hours for extraction. Next, remove the mixing stick and dry its surface. The pre-prepared SBSE was analyzed by TD-GC/MS, with the optimized thermal desorption conditions: desorption temperature 275 â, desorption time 15 min, cryofocusing temperature-40 â. RESULTS: Regression equations revealed acceptable linearity(correlation coefficients >0.986) across the working-standard range from 200-2000 ng/L for the 32 analytes. The limits of detection(LODs)were further evaluated were from 1.13-121 ng/L. With the optimized pretreatment method, the spiked recoveries of tap samples(200 and 2000 ng/L)were in the range of 62.5%-98.4% with the relative standard deviations(RSDs) of 3.5%-25.3%. CONCLUSION: The established method can realize the rapid detection of high throughput in the laboratory, it is simple, convenient to operate, and the extraction and analysis time is short.
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Cromatografía de Gases y Espectrometría de Masas , Ácidos Ftálicos , Hidrocarburos Policíclicos Aromáticos , Contaminantes Químicos del Agua , Cromatografía de Gases y Espectrometría de Masas/métodos , Hidrocarburos Policíclicos Aromáticos/análisis , Contaminantes Químicos del Agua/análisis , Ácidos Ftálicos/análisis , Adsorción , Agua Potable/análisis , Agua Potable/químicaRESUMEN
Candida albicans (C. albicans) is an opportunistic pathogen increasingly causing candidiasis worldwide. This study aims to investigate the pattern of systemic immune responses triggered by C. albicans with disease associated variation of Sap2, identifying the novel evasion strategies utilized by clinical isolates. Specifically, a variation in clinical isolates is identified at nucleotide position 817 (G to T). This homozygous variation causes the 273rd amino acid exchange from valine to leucine, close to the proteolytic activation center of Sap2. The mutant (Sap2-273L) generated from SC5314 (Sap2-273V) background carrying the V273L variation within Sap2 displays higher pathogenicity. In comparison to mice infected with Sap2-273V strain, mice infected with Sap2-273L exhibit less complement activation indicated by less serum C3a generation and weaker C3b deposition in the kidney. This inhibitory effect is mainly achieved by Sap2273L -mediated stronger degradation of C3 and C3b. Furthermore, mice infected with Sap2-273L strain exhibit more macrophage phenotype switching from M0 to M2-like and more TGF-ß release which further influences T cell responses, generating an immunosuppressed cellular microenvironment characterized by more Tregs and exhausted T cell formation. In summary, the disease-associated sequence variation of Sap2 enhances pathogenicity by complement evasion and M2-like phenotype switching, promoting a more efficient immunosuppressed microenvironment.
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Candida albicans , Proteínas Fúngicas , Animales , Ratones , Candida albicans/genética , Proteínas Fúngicas/genética , Macrófagos , Fenotipo , Virulencia/genéticaRESUMEN
Myocardial infarction (MI) is one of the diseases with high fatality rate. Berberine (BBR) is a monomer compound with various biological functions. And some studies have confirmed that BBR plays an important role in alleviating cardiomyocyte injury after MI. However, the specific mechanism is unclear. In this study, we induced a model of MI by ligation of the left anterior descending coronary artery and we surprisingly found that BBR significantly improved ventricular remodeling, with a minor inflammatory and oxidative stress injury, and stronger angiogenesis. Moreover, BBR inhibited the secretion of Wnt5a/ß-catenin pathway in macrophages after MI, thus promoting the differentiation of macrophages into M2 type. In summary, BBR effectively improved cardiac function of mice after MI, and the potential protective mechanism was associated with the regulation of inflammatory responses and the inhibition of macrophage Wnt5a/ß-catenin pathway in the infarcted heart tissues. Importantly, these findings supported BBR as an effective cardioprotective drug after MI.
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Berberina , Infarto del Miocardio , Ratones , Animales , Berberina/farmacología , beta Catenina/metabolismo , Miocardio , Infarto del Miocardio/tratamiento farmacológico , Miocitos Cardíacos , Macrófagos/metabolismoRESUMEN
Ulcerative colitis (UC) is a chronic inflammatory bowel disease caused by many factors including colonic inflammation and microbiota dysbiosis. Previous studies have indicated that celastrol (CSR) has strong anti-inflammatory and immune-inhibitory effects. Here, we investigated the effects of CSR on colonic inflammation and mucosal immunity in an experimental colitis model, and addressed the mechanism by which CSR exerts the protective effects. We characterized the therapeutic effects and the potential mechanism of CSR on treating UC using histological staining, intestinal permeability assay, cytokine assay, flow cytometry, fecal microbiota transplantation (FMT), 16S rRNA sequencing, untargeted metabolomics, and cell differentiation. CSR administration significantly ameliorated the dextran sodium sulfate (DSS)-induced colitis in mice, which was evidenced by the recovered body weight and colon length as well as the decreased disease activity index (DAI) score and intestinal permeability. Meanwhile, CSR down-regulated the production of pro-inflammatory cytokines and up-regulated the amount of anti-inflammatory mediators at both mRNA and protein levels, and improved the balances of Treg/Th1 and Treg/Th17 to maintain the colonic immune homeostasis. Notably, all the therapeutic effects were exerted in a gut microbiota-dependent manner. Furthermore, CSR treatment increased the gut microbiota diversity and changed the compositions of the gut microbiota and metabolites, which is probably associated with the gut microbiota-mediated protective effects. In conclusion, this study provides the strong evidence that CSR may be a promising therapeutic drug for UC.
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Colitis Ulcerosa , Colitis , Microbioma Gastrointestinal , Ratones , Animales , Colitis Ulcerosa/inducido químicamente , Colitis Ulcerosa/tratamiento farmacológico , Sulfato de Dextran/efectos adversos , ARN Ribosómico 16S/genética , Colitis/tratamiento farmacológico , Colitis/metabolismo , Antiinflamatorios/efectos adversos , InflamaciónRESUMEN
Increasing evidence indicates that the tumor microenvironment appears to play an increasingly important role in cancer progression and therapeutic resistance. Several types of cells within the tumor stroma had distinct impacts on cancer progression, either promoting or inhibiting cancer cell growth. Mesenchymal stem cells (MSCs) are a distinct type of cells that is linked to tumor development. MSCs are recognized for homing to tumor locations and promoting or inhibiting cancer cell proliferation, angiogenesis and metastasis. Moreover, emerging studies suggests that MSCs are also involved in therapeutic resistance. In this review, we analyzed the existing researches and elaborate on the functions of MSCs in cancer progression and anticancer therapeutic resistance, demonstrating that MSCs may be a viable cancer therapeutic target.
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Interleukin-22 (IL-22), a member of the IL-10 family of cytokines, is produced by a number of immune cells involved in the immune microenvironment of the body. IL-22 plays its pivotal roles by binding to the IL-22 receptor complex (IL-22R) and subsequently activating the IL-22R downstream signalling pathway. It has recently been reported that IL-22 also contributes to the pathogenesis of many connective tissue diseases (CTDs). In this review, we will discuss the role of IL-22 in several CTDs, such as system lupus erythematosus, rheumatoid arthritis, Sjögren's syndrome, systemic sclerosis and dermatomyositis, suggesting that IL-22 may be a potential therapeutic target in CTDs.
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BACKGROUND: The available treatments for refractory hyperkeratotic eczema are inadequate with frustrating results. We, therefore, incorporated Calcipotriol and Betamethasone Dipropionate (Daivobet®), and Viaminate into the mainstay treatment to improve the clinical symptoms. The study aimed to evaluate the efficacy of Daivobet ® and Viaminate as a potential treatment alternative for refractory hyperkeratotic eczema. PATIENTS AND METHODS: Between 2013 and 2015, 61 patients diagnosed with refractory hyperkeratotic eczema (RHE) who had shown inadequate response to conventional therapies were pooled from a single center. Besides, they were all treated with Daivobet ® , Viaminate, and an occlusive dressing mixture containing 5% salicylic acid ointment and 25% zinc oxide paste following inadequate response to conventional therapies (corticosteroids plus 25% zinc oxide paste and 5% salicylic acid ointment). Investigators Global Assessment (IGA) and Patient-Oriented Eczema Measure (POEM) assessed baseline and outcome measures for the degree of hyperkeratinization (0-clear; 3-moderate; 4-severe). RESULTS: Of the 61 patients, 49 (80.3%) patients presented with moderate RHE and 12 (19.7%) with severe RHE. After 24 weeks of treatment, the period for loss of keratinization was significantly lower in patients with moderate RHE (3.9±1.9 weeks) than those with severe RHE (10.8±1.0 weeks) with a P-value <0.01. Furthermore, they required a significantly shorter total treatment duration (10.6 ± 4.3 weeks) than those with severe RHE (20.3±3.6 weeks) with a P-value of <0.01. However, there were no significant differences in post hoc analysis at week 36 with P-values of 0.46 and 1.00 for IGA and POEM, respectively. CONCLUSION: Our results showed that the incorporation of Viaminate and Daivobet® into mainstay treatment was effective and safe for the long-term management of RHE.
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Background: Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) induced Coronavirus Disease 2019 (COVID-19) has posed a global threat to public health. The immune system is crucial in defending and eliminating the virus and infected cells. However, immune dysregulation may result in the rapid progression of COVID-19. Here, we evaluated the subsets, phenotypic and functional characteristics of natural killer (NK) and T cells in patients with COVID-19 and their associations with disease severity. Methods: Demographic and clinical data of COVID-19 patients enrolled in Wuhan Union Hospital from February 25 to February 27, 2020, were collected and analyzed. The phenotypic and functional characteristics of NK cells and T cells subsets in circulating blood and serum levels of cytokines were analyzed via flow cytometry. Then the LASSO logistic regression model was employed to predict risk factors for the severity of COVID-19. Results: The counts and percentages of NK cells, CD4+ T cells, CD8+ T cells and NKT cells were significantly reduced in patients with severe symptoms. The cytotoxic CD3-CD56dimCD16+ cell population significantly decreased, while the CD3-CD56dimCD16- part significantly increased in severe COVID-19 patients. More importantly, elevated expression of regulatory molecules, such as CD244 and programmed death-1 (PD-1), on NK cells and T cells, as well as decreased serum cytotoxic effector molecules including perforin and granzyme A, were detected in patients with COVID-19. The serum IL-6, IL-10, and TNF-α were significantly increased in severe patients. Moreover, the CD3-CD56dimCD16- cells were screened out as an influential factor in severe cases by LASSO logistic regression. Conclusions: The functional exhaustion and other subset alteration of NK and T cells may contribute to the progression and improve the prognosis of COVID-19. Surveillance of lymphocyte subsets may in the future enable early screening for signs of critical illness and understanding the pathogenesis of this disease.
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Linfocitos T CD8-positivos/citología , COVID-19/sangre , Células Asesinas Naturales/citología , SARS-CoV-2/fisiología , Adulto , Anciano , Linfocitos T CD8-positivos/inmunología , COVID-19/epidemiología , COVID-19/inmunología , COVID-19/virología , China/epidemiología , Femenino , Citometría de Flujo , Humanos , Células Asesinas Naturales/inmunología , Recuento de Leucocitos , Masculino , Persona de Mediana Edad , Pandemias , Pronóstico , SARS-CoV-2/genética , Subgrupos de Linfocitos T/citología , Subgrupos de Linfocitos T/inmunologíaRESUMEN
BACKGROUND: Since December 2019, novel coronavirus (SARS-CoV-2)-induced pneumonia (COVID-19) occurred in Wuhan, and rapidly spread throughout China. COVID-19 patients demonstrated significantly different outcomes in clinic. We aimed to figure out whether obesity is a risk factor influencing the progression and prognosis of COVID-19. METHODS: 95 patients with COVID-19 were divided into obesity group and non-obesity group according to their body mass index (BMI). The demographic data, clinical characteristics, laboratory examination, and chest computed tomography (CT) were collected, analyzed and compared between two groups. RESULTS: Our data showed that COVID-19 patients with obesity had more underlying diseases and higher mortality rate compared to those without obesity. Furthermore, patients with obesity also demonstrated more severe pathological change in lung and higher blood lymphocytes, triglycerides, IL-6, CRP, cystatin C, alanine aminotransferase (ALT), erythrocyte sedimentation rate (ESR), which may greatly influence disease progression and poor prognosis of COVID-19. CONCLUSIONS: It suggest that obesity contributes to clinical manifestations and may influence the progression and prognosis of COVID-19 and it is considered as a potential risk factor of the prognosis of COVID-19. Special medical care and appropriate intervention should be performed in obesity patients with COVID-19 during hospitalization and later clinical follow-up, especially for those with additional other comorbidities.
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COVID-19/fisiopatología , Obesidad/virología , COVID-19/sangre , COVID-19/epidemiología , COVID-19/patología , Citocinas/sangre , Humanos , Pulmón/diagnóstico por imagen , Pulmón/patología , Obesidad/sangre , Obesidad/epidemiología , Obesidad/fisiopatología , Pandemias , Factores de Riesgo , SARS-CoV-2/aislamiento & purificación , Tomografía Computarizada por Rayos XRESUMEN
OBJECTIVE: To establish a rapid method for simultaneous determination of 16 polycyclic aromatic hydrocarbons(PAHs) in source water and tap water by performance liquid chromatography(HPLC) with ultraviolet detector(UV) tandem fluorescence detector(FLR). METHODS: Source water was filtered by GF/C glass fiber filters and tap water were added ascorbic acid of 60 mg per liter to remove the residual chlorine when sampling. 500 mL water sample were sampled and adjusted pH 2 with phosphoric acid, then 10 mL methanol were added. Then samples were concentrated by styrene stilbene polymer solid phase extraction column, after loading samples, 50 percent methanol aqueous solution adjust pH 2 were used for washing bottle and the washed solution were continuum loaded. Then 80 percent methanol aqueous solution was used for removing impurity interference and elution with dichloromethane. The eluent was nitrogen blow to near dry after adding 100 µL 10 percent tween-20 methanol solutions(m/V). Acetonitrile was used for reconstitution, and then separated by PAH chromatography column using acetonitrile and pure water at gradient elution, and detected by UV tandem FLR detector. RESULTS: The linear ranges of 16 PAHs were 0. 5 to 500 ng/mL and the correlation coefficients were greater than 0. 999. The method detection limit and limits of quantification were 0. 3 to 5. 0 ng/L and 1. 2 to 20. 0 ng/L, respectively. The recoveries were in the range of 67. 2%-114. 1% with the relative standard deviations ranging from 1. 5%-14. 0%(n=6). Then the established method was used for the determination of 17 water samples, 8 kinds, 6 kinds and 7 kinds of PAHs were detected in source water, tap water and pipe net tap water, respectively. CONCLUSION: The method is rapid, sensitive and selective, and has been successfully applied for determination of 16 PAHs in source water and tap water.
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Hidrocarburos Policíclicos Aromáticos/análisis , Contaminantes Químicos del Agua/análisis , Cromatografía Líquida de Alta Presión , Cromatografía Liquida , Extracción en Fase Sólida , AguaRESUMEN
The outbreak of COVID-19, caused by severe acute respiratory syndrome coronavirus 2, started in December 2019, Wuhan, China. We aimed to figure out the time-point and duration of using antiviral drugs for receiving the maximal effects in patients with COVID-19. In this study, we enrolled 129 confirmed COVID-19 mild to moderate patients who had been treated with antiviral drugs during their hospitalization in Wuhan Union Hospital China. The patients were divided into an early antiviral treatment group and late antiviral treatment group. The demographic data, laboratory tests, the virus clearance time, chest computed tomography scans, and so forth were extracted, calculated, and compared between two groups. Our data showed that the median time from illness onset to initiation of antiviral treatment was 6 days in all patients. The group with early antiviral treatment demonstrated 7 days shorter in the virus clearance time when compared to the group with late antiviral treatment. After virus clearance, the group with early antiviral treatment showed milder illness than the group with late antiviral treatment. Early antiviral treatment could effectively shorten the virus clearance time, and prevent the rapid progression of COVID-19. Therefore, the COVID-19 patients should receive combined therapies with antiviral treatment at an early stage.
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Antivirales/uso terapéutico , Tratamiento Farmacológico de COVID-19 , Carga Viral/efectos de los fármacos , Adulto , Anciano , Anciano de 80 o más Años , Antivirales/administración & dosificación , China , Comorbilidad , Esquema de Medicación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Tórax/diagnóstico por imagen , Factores de Tiempo , Tomografía Computarizada por Rayos X , Adulto JovenRESUMEN
BACKGROUND AND AIM: A novel coronavirus severe acute respiratory syndrome corona virus 2 (SARS-CoV-2) caused pneumonia, Coronavirus Disease 2019 (COVID-19), broke out in Wuhan, China in December 2019, and spread all over the world. Patients with COVID-19 showed huge differences in the hospital stay, progression, and prognosis. As reported, the comorbidities may play an important role in COVID-19. Here, we aim to address the role of cardiovascular disease (CVD) in the progression and prognosis of COVID-19. METHODS AND RESULTS: Eighty-three confirmed COVID-19 patients were divided into CVD (n = 42) and non-CVD (n = 41) group according to their medical history. Medical records including demographic data, medical history, clinical characteristics, laboratory examinations, chest computed tomography (CT), and treatment measures were collected, analyzed, and compared between the two groups. COVID-19 patients with CVD showed (1) more severe pathological changes in the lungs, (2) elevated injury-related enzymes including α-hydroxybutyrate dehydrogenase (HDBH), lactic dehydrogenase (LDH), γ-glutamyltransferase (GGT), creatine kinase (CK), and alanine aminotransferase (ALT), (3) significantly increased uncontrolled inflammation related markers, such as c-reactive protein (CRP), interleukin (IL)-6, serum ferritin, erythrocyte sedimentation rate (ESR), and serum amyloid A (SAA), (4) serious hypercoagulable status reflected by increased D-dimer and serum fibrinogen (FIB), and (5) higher mortality, compared to COVID-19 patients without CVD. CONCLUSIONS: Our data indicated that CVD is a strong risk factor for rapid progression and bad prognosis of COVID-19. More intensive medical care should be applied to patients with CVD to prevent rapid deterioration of the disease.
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Betacoronavirus , Enfermedades Cardiovasculares/epidemiología , Causas de Muerte , Infecciones por Coronavirus/epidemiología , Brotes de Enfermedades/estadística & datos numéricos , Progresión de la Enfermedad , Neumonía Viral/epidemiología , Adulto , Anciano , Biomarcadores/sangre , Análisis Químico de la Sangre , Proteína C-Reactiva/metabolismo , COVID-19 , Enfermedades Cardiovasculares/diagnóstico , Enfermedades Cardiovasculares/terapia , China/epidemiología , Estudios de Cohortes , Comorbilidad , Infecciones por Coronavirus/diagnóstico , Infecciones por Coronavirus/terapia , Bases de Datos Factuales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pandemias , Neumonía Viral/diagnóstico , Neumonía Viral/terapia , Valores de Referencia , Estudios Retrospectivos , SARS-CoV-2 , Análisis de Supervivencia , Tomografía Computarizada por Rayos X/métodosRESUMEN
BACKGOUND: To figure out whether diabetes is a risk factor influencing the progression and prognosis of 2019 novel coronavirus disease (COVID-19). METHODS: A total of 174 consecutive patients confirmed with COVID-19 were studied. Demographic data, medical history, symptoms and signs, laboratory findings, chest computed tomography (CT) as well the treatment measures were collected and analysed. RESULTS: We found that COVID-19 patients without other comorbidities but with diabetes (n = 24) were at higher risk of severe pneumonia, release of tissue injury-related enzymes, excessive uncontrolled inflammation responses and hypercoagulable state associated with dysregulation of glucose metabolism. Furthermore, serum levels of inflammation-related biomarkers such as IL-6, C-reactive protein, serum ferritin and coagulation index, D-dimer, were significantly higher (P < .01) in diabetic patients compared with those without, suggesting that patients with diabetes are more susceptible to an inflammatory storm eventually leading to rapid deterioration of COVID-19. CONCLUSIONS: Our data support the notion that diabetes should be considered as a risk factor for a rapid progression and bad prognosis of COVID-19. More intensive attention should be paid to patients with diabetes, in case of rapid deterioration.
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A rapid and sensitive method was developed to determine 131 pesticides in tea by on-line gel permeation chromatography-gas chromatography tandem mass spectrometer (on-line GPC-GC-MS/MS) using graphitized multi-walled carbon nanotubes (MWCNTs) as dispersive solid phase extraction (DSPE) sorbent in sample pretreatment. Sample clean-up performance of various functionalized MWCNTs and their influences to recoveries were investigated. In the method validation, good linearity correlation coefficients (R2) were obtained, which were higher than 0.99 for all pesticides. The percent recoveries were 78.2%-113.9% at the spiked concentration levels of 20, 50 and 200⯵g/kg with relative standard deviations (RSDs, nâ¯=â¯6) lower than 15.8%. Limits of detections (LODs) were in the range of 0.5-5.0⯵g/kg. This method is simple and fast with relatively high sensitivity and can achieve the requirements of pesticides analysis.
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Nanotubos de Carbono/química , Residuos de Plaguicidas/análisis , Plaguicidas/química , Té/química , Cromatografía en Gel , Cromatografía de Gases y Espectrometría de Masas/métodos , Límite de Detección , Residuos de Plaguicidas/aislamiento & purificación , Reproducibilidad de los Resultados , Extracción en Fase Sólida , Té/metabolismoRESUMEN
A reliable and rapid method was developed to determine benzobicyclon residue in different soil and sediment samples. After extraction via a modified quick, easy, cheap, effective, rugged, and safe method, samples were purified by SPE cleanup with HLB cartridges. Quantitative determination was performed by ultra-HPLC (UPLC)-tandem MS (MS/MS) in electrospray positive ionization and multiple reaction monitoring modes. When samples were fortified at concentrations of 5, 50, and 500 µg/L, recoveries of 80.2 to 114.5% were obtained, with the repeatability (intraday RSDr) and reproducibility (interday RSDR) <14.1 and <21.4%, respectively. The instrumental LODs and LOQs for matrix-matched standards and the method LOQs for sample test were 0.19-1.34 µg/L, 0.64-4.48 µg/L, and 0.32-2.24 µg/kg, respectively. The linear range was 5-1000 µg/L (R2 > 0.99). The established UPLC-MS/MS method was applied in the detection of benzobicyclon in real soil samples, which were collected during the supervised field trial. Results showed that the maximum concentration of benzobicyclon in the soil was 4.87 mg/kg and its degradation half-life (t0.5) was 6.7 days. Generally, the proposed method could be an effective tool for controlling and monitoring the risks posed by benzobicyclon to human health and environmental safety.
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Compuestos Bicíclicos con Puentes/análisis , Sedimentos Geológicos/química , Residuos de Plaguicidas/análisis , Suelo/química , Sulfonas/análisis , Cromatografía Líquida de Alta Presión , Espectrometría de Masas en TándemRESUMEN
In order to better assess their environmental risks, the sorption and degradation of triphenyltin hydroxide, azocyclotin and fenbutatin oxide were studied in two sediments under varying laboratory conditions in this study. An analytical method for simultaneous determination of the three organotins in environmental samples was firstly developed using high performance liquid chromatography-inductively coupled plasma-mass spectrometry (HPLC-ICP-MS). The limit of detection and limit of quantification for standards ranged from 0.13 to 1.46 µg/L. Fortification study showed that when spiked at 2-250 µg/kg the mass recoveries were 73.7-119.6%. Sorption isotherm experiments indicated that the organotins could be strongly adsorbed by the sediments, and organotin sorption kinetics obeyed the pseudo second-order kinetic model. The sorption affinity was inversely related to their water solubility. All isotherms fitted with the Henry mode fairly well (r(2) > 0.96) with distribution coefficients (Kd) ranging from 746.1 to 2465.2 mL/g. The three organotins could rapidly move from the upper water layer to the lower sediment layer, and they were all of moderate degradation compounds with the degradation half lives varying from 38.3 to 84.5d in anaerobic and aerobic water-sediment systems. The degradation rate seemed to be positively related to organic matter content of sediment. Result inferred that the three organotins had the low risks to pollute groundwater when applied on dry land and could moderately degrade in water-sediment system. However, more attention should still be paid to these organotins due to the wide application on agricultural field.
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Cromatografía Líquida de Alta Presión , Plaguicidas , Adsorción , Agua Dulce , Sedimentos Geológicos/química , Espectrometría de MasasRESUMEN
In order to provide the scientific basis for the environmental risk assessment of cycloxaprid and 6-Cl-PMNI (intermediate of cycloxaprid), the degradation properties of 6-Cl-PMNI in aerobic, anaerobic and/or sterile soil, as well as in water with different pH values at different temperature were explored under laboratory conditions using HPLC for its kinetics study and UPLC-MS/MS for the identification of its metabolites/degradation products. Fortification study showed that the recoveries of 71.4-100.5% with the maximum coefficient variation (CV) of 7.47% were obtained. The linear range was 0.1-10 mg/L with the good linearity of R(2) = 0.9990. For standard, the method LOD (limit of detection) and LOQ (limit of quantification) was 0.03 mg/L and 0.1 mg/L, respectively. Results demonstrated the good performance of the developed method. Kinetics study indicated that the degradation half-lives (t0.5) in pH 3-pH 10 buffers varied from 111.8 d to 288.8 d at 25 °C but rapidly shortened to 1.6-25.7 d at 70 °C. Good negative linear ships (R(2) ≥ 0.8423) between half life and temperature were found. 6-Cl-PMNI could be readily degraded in non-sterile soil (t0.5 0.8-7.5 d) while slowly degraded in sterile soil (t0.5 64.8-91.2 d). Three hydrolytic products and one metabolite of 6-Cl-PMNI in aerobic soil were identified. The CC olefinic bond reacted with H2O by Markovnikov Additive Reaction and the split of C-Cl were mainly proposed as the possible reaction pathway for 6-Cl-PMNI degradation in water and in soil, respectively.
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Compuestos Heterocíclicos con 3 Anillos/metabolismo , Insecticidas/metabolismo , Piridinas/metabolismo , Contaminantes del Suelo/metabolismo , Contaminantes Químicos del Agua/metabolismo , Biodegradación Ambiental , Cromatografía Líquida de Alta Presión , Semivida , Concentración de Iones de Hidrógeno , Hidrólisis , Cinética , Microbiología del Suelo , Espectrometría de Masas en Tándem , Temperatura , Microbiología del AguaRESUMEN
A reliable and rapid method has been optimized to determine the residue of amicarthiazol in soil and environmental water samples. After extraction and evaporation, the extraction was carried out with solid phase extraction (SPE) cleanup using HLB cartridge (only soil samples) and for the quantitative determination by ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The resulting residues of amicarthiazol were analyzed by a gradient separation performed on a UPLC system with a C18 column, methanol and water containing 0.1% (v v(-1)) formic acid as the mobile phase in the mode of electrospray positive ionization (ESI(+)) and multiple reaction monitoring (MRM). Results showed that the recoveries for spiked samples were 74.4-97.1% and 72.1-109.9% for soil and water, respectively, with the relative standard deviation (RSD) less than 10.2% when fortified at 10, 100 and 1000µgL(-1). The limits of detection (LODs) and the limits of quantification (LOQs) for matrix matched standards ranged from 0.073-0.425µgL(-1) and 0.243-1.42µgL(-1). The intra-day precision (n=5) and the inter-day precision over 10 days (n=10) for the amicarthiazol in soils and water samples spiked at 100µgL(-1) was 7.9% and 15.9%, respectively. Results indicated that the developed method could be a helpful tool for the controlling and monitoring of the risks posed by amicarthiazol to human health and environment safety.
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Anilidas/análisis , Cromatografía Liquida/métodos , Contaminantes del Suelo/análisis , Espectrometría de Masas en Tándem/métodos , Tiazoles/análisis , Contaminantes Químicos del Agua/análisis , Residuos de Medicamentos/análisis , Fungicidas Industriales/análisis , Extracción en Fase SólidaRESUMEN
Saflufenacil is a new protoporphyrinogen-IX-oxidase inhibitor herbicide. When used, it can enter the soil and has a high risk to reach and contaminate groundwater and aquatic systems. A rapid and sensitive method of ultra-performance LC with MS/MS was developed for the simultaneous determination of saflufenacil and its two metabolites in soil samples. A modified quick, easy, cheap, effective, rugged, and safe method was applied as the pretreatment procedure. The method was validated by five types of soil samples collected from several regions of China, which all showed good linearity (R(2) ≥ 0.9914) and precision (RSD ≤ 26.2%). The average recoveries of the three analytes ranged between 74.1 and 118.9% at spiking levels of 3-300 µg/kg. The method limits of detection (S/N 3:1) and method limits of quantification (S/N 10:1) achieved are in the ranges of 0.25-2.75 and 0.83-9.16 µg/kg, respectively. This indicated that the developed ultra-performance LC with MS/MS method is a promising analytical tool for monitoring the environmental risks posed by saflufenacil.