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1.
Chemosphere ; 339: 139704, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37536542

RESUMO

Cooking oil fumes (COFs) comprised of a mixture of cancer-causing volatile organic aldehydes (VOAs), particularly trans, trans-2,4-decadienal (t,t-DDE), 4-hydroxy-hexenal (4-HHE), and 4-hydroxy-nonenal (4-HNE). Monitoring toxic VOAs levels in people exposed to different cooking conditions is vital to predicting the cancer risk. For this purpose, we developed a fast tissue extraction (FaTEx) technique combined with UHPLC-MS/MS to monitor three toxic VOAs in mice lung tissue samples. FaTEx pre-treatment protocol was developed by combining two syringes for extraction and clean-up process. The various procedural steps affecting the FaTEx sample pre-treatment process were optimized to enhance the target VOAs' extraction efficiency from the sample matrix. Under the optimal experimental conditions, results exhibit good correlation coefficient values > 0.99, detection limits were between 0.5-3 ng/g, quantification limits were between 1-10 ng/g, and the matrix effect was <18.1%. Furthermore, the extraction recovery values of the spiked tissue exhibited between 88.9-109.6% with <8.6% of RSD. Cooking oil fume (containing t,t-DDE) treated mice at various time durations were sacrificed to validate the developed technique, and it was found that t,t-DDE concentrations were from 14.8 to 33.8 µg/g. The obtained results were found to be a fast, reliable, and semi-automated sample pre-treatment technique with good extraction efficiency, trace level detection limit, and less matrix effect. Therefore, this method can be applied as a potential analytical method to determine the VOAs in humans exposed to long-term cooking oil fumes.


Assuntos
Aldeídos , Neoplasias , Humanos , Camundongos , Animais , Aldeídos/toxicidade , Aldeídos/análise , Espectrometria de Massas em Tandem , Gases , Pulmão/química , Culinária
2.
J Food Sci Technol ; 60(7): 1992-2000, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37206414

RESUMO

Identifying the risk of ochratoxin A in our daily food has become fundamental because of its toxicity. In this work, we report a novel semi-automated in-syringe-based fast mycotoxin extraction (IS-FaMEx) technique coupled with direct-injection electrospray-ionization tandem mass spectrometer (ESI-MS/MS) detection for the quantification of ochratoxin A in coffee and tea samples. Under the optimized conditions, the results reveal that the developed method's linearity was more remarkable, with a correlation coefficient of > 0.999 and > 92% extraction recovery with a precision of 6%. The detection and quantification limits for ochratoxin A were 0.2 and 0.8 ng g-1 for the developed method, respectively, which is lower than the European Union regulatory limit of toxicity for ochratoxin-A (5 ng g-1) in coffee. Furthermore, the newly developed modified IS-FaMEx-ESI-MS/MS exhibited lower signal suppression of 8% with a good green metric score of 0.64. In addition, the IS-FaMEx-ESI-MS/MS showed good extraction recovery, matrix elimination, good detection, and quantification limits with high accuracy and precision due to the fewer extraction steps with semi-automation. Therefore, the presented method can be applied as a potential methodology for the detection of mycotoxins in food products for food safety and quality control purposes. Supplementary Information: The online version contains supplementary material available at 10.1007/s13197-023-05733-z.

3.
Chemosphere ; 329: 138667, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37059207

RESUMO

Assessing the impact of human exposure to environmental toxicants is often crucial to biomonitoring the exposed dose. In this work, we report a novel fast urinary metabolites extraction (FaUMEx) technique coupled with UHPLC-MS/MS analysis for the highly sensitive and simultaneous biomonitoring of the five major urinary metabolites (thiodiglycolic acid, s-phenylmercapturic acid, t,t-muconic acid, mandelic acid, and phenyl glyoxylic acid) of common volatile organic compounds' (VOCs) exposure (vinyl chloride, benzene, styrene, and ethylbenzene) in human. FaUMEx technique comprises of two-steps, liquid-liquid microextraction was performed first in an extraction syringe using 1 mL of methanol (pH 3) as an extraction solvent and then, the extractant was passed through a clean-up syringe (pre-packed-with various sorbents including 500 mg anhydrous MgSO4, 50 mg C18, and 50 mg SiO2) to obtain the high order of matrice clean-up and preconcentration efficiency. The developed method displayed excellent linearity, and the correlation coefficients were >0.998 for all the target metabolites with detection and quantification limits of 0.02-0.24 ng mL-1 and 0.05-0.72 ng mL-1, respectively. Furthermore, the matrix effects were < ±5%, and inter and intra-day precision were <9%. Moreover, the presented method was applied and validated to real sample analysis for biomonitoring of VOC's exposure levels. The results showed that the developed FaUMEx-UHPLC-MS/MS method is fast, simple, low-cost, low-solvent consumption, high sensitivity with good accuracy and precision for five targeted urinary VOCs' metabolites. Therefore, the presented dual-syringe mode FaUMEx strategy with UHPLC-MS/MS technique can be applied to biomonitoring of various urinary metabolites to assess human exposure to environmental toxicants.


Assuntos
Espectrometria de Massas em Tandem , Compostos Orgânicos Voláteis , Humanos , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida de Alta Pressão/métodos , Monitoramento Biológico , Seringas , Dióxido de Silício
4.
Food Chem ; 417: 135951, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-36934712

RESUMO

In this study, we demonstrated a novel semi-automated in-syringe-based coagulant-assisted liquid-liquid microextraction (IS-CGA-LLME) as fast mycotoxin extraction (FaMEx) technique coupled with ultra-high-performance liquid chromatography connected with a tandem-mass spectrometer (UHPLC-MS/MS) for the quantification of mycotoxin (Ochratoxin A, OT-A) in coffee and tea samples. IS-CGA-LLME is a three-step extraction process that includes extraction of OT-A from sample matrix using low-volume solvent extraction, then the extractant was cleaned-up using a coagulation process, and finally, the decolorized/matrix removed sample solution was processed for LLME for target analyte's pre-concentration. The final extractant was analyzed using UHPLC-MS/MS for OT-A quantification. Under the optimized experimental conditions, highly sensitive detection and quantification limits were obtained at 0.001 and 0.003 ng g-1 for OT-A with excellent extraction recovery (93-111%) and precision <10%. These results proved that the developed method is a simple, highly sensitive, semi-automated, low-matrix effect and efficient procedure for the determination of mycotoxins in food samples.


Assuntos
Micotoxinas , Micotoxinas/análise , Cromatografia Líquida de Alta Pressão/métodos , Café/química , Espectrometria de Massas em Tandem/métodos , Seringas , Chá
5.
Environ Res ; 217: 114787, 2023 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-36410459

RESUMO

Nicotine is the most prominent psychoactive/addictive chemical substance consumed worldwide among young players in team sports. Moreover, urinary nicotine discharge and nicotine-based products disposal in environmental waters has been unavoidable in recent years. Therefore, sensitive monitoring of nicotine content in environmental waters and human urine samples is essential. In this study, we developed a miniaturized novel green, low-cost, sensitive, in-syringe-based semi-automated fast drug extraction (FaDEx) protocol coupled with gas chromatography-flame ionization detection (GC-FID) for the efficient environmental and bio-monitoring of nicotine in aqueous samples. The FaDEx method consists of two steps; firstly, the target analyte was extracted using dimethyl carbonate (a green solvent) and extraction salts. After that, the extraction solvent was passed automatically through the solid-phase extraction cartridge at a constant flow rate for the cleanup process to achieve the sensitive nicotine analysis by GC-FID. Under optimized experimental conditions, the developed method showed excellent linearity over the concentration ranges between 20-2000 ng mL-1 with a correlation coefficient >0.99. The detection and quantification limits were 4 and 20 ng mL-1, respectively. The presented method was applied to monitor and assess nicotine exposure in sports-persons' urine and environmental water samples. The method accuracy and precision in terms of relative recovery and relative standard deviation (for triplicate analysis) were 85.4-110.2% and ≤8%, respectively. Finally, the impact of our procedure on the environment from a green analytical chemistry view was assessed using a novel metric system called AGREE, and obtained the greenness score of 0.87, indicating its an efficient alternative green analytical protocol for routine environmental and bio-monitoring of nicotine in environmental and biological samples.


Assuntos
Nicotina , Água , Humanos , Nicotina/análise , Monitoramento Biológico , Limite de Detecção , Extração em Fase Sólida/métodos , Solventes , Psicotrópicos/análise
6.
Environ Res ; 217: 114823, 2023 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-36402184

RESUMO

In this work, we demonstrated a new, environmental-friendly and effective sample preparation strategy named 'in-syringe-assisted fast pesticides extraction (FaPEx)' technique coupled with LC-MS/MS for the rapid identification and monitoring of emerging pollutant fipronil and its metabolite fipronil sulfone in chicken egg and environmental soil samples. FaPEx strategy comprising of two simple steps. Firstly, the sample was placed in the syringe and extracted using low-volume acetonitrile with NaCl and anhydrous MgSO4 salts. Secondly, the extractant was passed through in-syringe-based solid-phase extraction (SPE) kit containing cleanup sorbents and salt combinations (C18, primary secondary amine, and anhydrous MgSO4) for the cleanup process. Then, the obtained clean extractant was injected into LC-MS/MS for the quantification of target analytes. Various important parameters influencing the FaPEx performances, such as solvent type, salt type, salt amount, sorbent type, and amount, were examined and optimized. The method validation results showed excellent linearity with high correlation coefficients were ≥ 0.99. The estimated LODs were between 0.05-0.07 µg/kg, and LOQs ranged between 0.1-0.25 µg/kg for target analytes in both egg and soil sample matrices, and precision values were ≤7.90%. The developed method was applied to commercial chicken egg samples and environmental soil samples analysis. Spiked recoveries ranged between 88.75-110.91% for egg samples with RSDs ≤7.42% and 82.47-107.46% for soil samples with RSDs <7.37%. These results proved that the developed sample preparation method is a simple, fast, green, low-cost, and efficient method for the analysis of fipronil and its metabolites in food and environmental samples. Thus, this method can be applied as an alternative analytical methodology in routine and standard food and environmental testing laboratories.


Assuntos
Poluentes Ambientais , Praguicidas , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida , Cromatografia Líquida de Alta Pressão/métodos , Extração em Fase Sólida/métodos , Solo
7.
J Microbiol Immunol Infect ; 54(4): 658-664, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32507618

RESUMO

BACKGROUND: Shewanella algae is a zoonotic pathogen that poses a serious health threat to immunocompromised hosts. Treatment of S. algae infections is challenging due to the pathogen's intrinsic resistance to a variety of ß-lactam antibiotics. Therapeutic options have become further limited by the emergence of quinolone-resistant strains. Currently, there are few studies concerning the genetic and molecular mechanisms underlying acquired quinolones resistance in S. algae. qnrA was once proposed as the candidate gene related to quinolones resistance in S. algae. However, recent studies demonstrated qnrA are highly conservative and does not confer resistance to quinolones in S. algae. METHODS: A total of 27 non-duplicated isolates of S. algae strains were examined. MICs of ciprofloxacin were determined using Vitek 2. Whole genome sequencing was performed using MiSeq platform. Comprehensive Antibiotic Resistance Database and ResFinder were used for annotation of quinolones resistance genes. Multiple sequence alignment by EMBOSS Clustal Omega were used to identified mutation in quinolone resistance-determining regions. To investigation of the alteration of protein structure induced by mutation, in silico molecular docking studies was conducted using Accryl Discovery studio visualizer. RESULTS: All S. algae harbored the quinolone-resistance associated genes (qnrA, gyrA, gyrB, parC, and parE) regardless its resistance to ciprofloxacin. Comparison of these genomes identified a nonsynonymous mutation (S83V) in chromosome-encoded gyrase subunits (GyrA) in quinolone-resistant strain. We found this mutation disrupts the water-metal ion bridge, reduces the affinity of the quinolone-enzyme complex for the metal ions and therefore decrease the capability of quinolones to stabilize cleavage complexes. CONCLUSIONS: The study provides insight into the quinolone resistance mechanisms in S. algae, which would be helpful for the evolution of antibiotic resistance in this bacterium.


Assuntos
Antibacterianos/farmacologia , DNA Girase/genética , Farmacorresistência Bacteriana/genética , Genômica/métodos , Mutação , Quinolonas/farmacologia , Shewanella/genética , Infecções por Bactérias Gram-Negativas/microbiologia , Humanos , Testes de Sensibilidade Microbiana , Shewanella/patogenicidade , Sequenciamento Completo do Genoma/métodos
9.
11.
Int J Emerg Med ; 3(4): 381-4, 2010 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-21373309

RESUMO

BACKGROUND: There are many combinations of treatments for pyogenic liver abscess (PLA). Different treatments are indicated for different clinical courses of PLA. AIMS: To realize the current prevalence, clinical course, trend of treatment, and prognosis of pyogenic liver abscess (PLA) in Taiwan. METHODS: We retrospectively reviewed the medical records of 126 patients with PLA. We divided them into four groups: M, MD, MS, and MDS, represented as parenteral antibiotic only, parenteral antibiotic with drainage, parenteral antibiotic with surgical intervention, and parenteral antibiotic with surgical drainage. We analyzed data by commercial statistical software (SPSS for Windows, version 11.0, SPSS Ltd., Chicago, IL). We used Student's t-test and χ(2) test for statistical analyses, and significance was set at a p value less than 0.05. RESULTS: PLA patients who were treated only with parenteral antibiotics had early diagnosis of PLA with a mean fever period of 3.3 days (p = 0.043). Patients who needed surgical drainage were highly associated with shock presentation in the clinical course (35.7% versus 14.3%, p = 0.007). CONCLUSION: The earlier we can diagnose PLA, the shorter the patient's hospital stay (20.6 days) will be. In PLA patients with shock, a higher rate of surgical intervention is mandatory to save their lives.

12.
Cell Signal ; 21(6): 881-91, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19385050

RESUMO

Neuro-2a (N2a) cells are derived from spontaneous neuroblastoma of mouse and capable to differentiate into neuronal-like cells. Recently, P2X7 receptor has been shown to sustain growth of human neuroblastoma cells but its role during neuronal differentiation remains unexamined.We characterized the role of P2X7 receptors in the retinoic acid (RA)-differentiated N2a cells. RA induced N2a cells differentiation into neurite bearing and neuronal specific proteins, microtubule-associated protein 2 (MAP2) and neuronal specific nuclear protein (NeuN), expressing neuronal-like cells. Interestingly, the RA-induced neuronal differentiation was associated with decreases in the expression and function of P2X7 receptors. Functional inhibition of P2X7 receptors by P2X7 receptor selective antagonists, 5'-triphosphate, periodate-oxidized 2',3'-dialdehyde ATP (oATP), brilliant blue G (BBG) or A438079 induced neurite outgrowth. In addition, RA and oATP treatment stimulated the expression of neuron-specific class III beta-tubulin (TuJ1), and knockdown of P2X7 receptor expression by siRNA induced neurite outgrowth. To elucidate the possible mechanism, we found the levels of basal intracellular Ca2+ concentrations ([Ca2+]i) were decreased in either RA- or oATP-differentiated or P2X7receptor knockdown N2a cells. Simply cultured N2a cells in low Ca2+ medium induced a 2-fold increase in neurite length. Treatment of N2a cells with ATP hydrolase apyrase and the P2X7 receptors selective antagonist oATP or BBG decreased cell viability and cell number. Nevertheless, oATP but not BBG decreased cell proliferation and cell cycle progression. These results suggest for the first time that decreases in expression/function of P2X7 receptors are involved in neuronal differentiation.We provide additional evidence shown that the ATP release-activated P2X7 receptor is important in maintaining cell survival of N2a neuroblastoma cells.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Neuroblastoma/metabolismo , Neuroblastoma/patologia , Neurônios/citologia , Neurônios/efeitos dos fármacos , Receptores Purinérgicos P2/metabolismo , Tretinoína/farmacologia , Trifosfato de Adenosina/análogos & derivados , Trifosfato de Adenosina/farmacologia , Animais , Sinalização do Cálcio/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Camundongos , Neuritos/efeitos dos fármacos , Neuritos/metabolismo , Antagonistas do Receptor Purinérgico P2 , RNA Interferente Pequeno/metabolismo , Receptores Purinérgicos P2X7
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