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1.
Anal Biochem ; 638: 114496, 2022 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-34838816

RESUMEN

LC-MS/MS has recently emerged as the best practice for simultaneous analysis of 2, 4, 6 Trinitrotoluene (TNT) and its metabolites. We have developed and validated an LC-MS/MS method for simultaneous quantification of 2, 4, 6 Trinitrotoluene (TNT) and its metabolites 4-ADNT, 2-ADNT, 2,4-DNT, and 2,6-DNT in urine samples. These four metabolites were acid hydrolyzed using 1 mL of urine followed by extraction using n-Hexane and ethyl acetate as an extracting solvent. Separation was achieved by centrifugation, and the supernatant was dried under nitrogen, reconstituted with water and acetonitrile, and then filtered. Chromatographic separation was achieved on Agilent Poroshel 120 EC-C18 column (2.1 mm × 75 mm × 2.7 µm) utilizing two mobile phases 0.1% formic acid in water and 0.1% formic acid in acetonitrile in gradient flow. The validated AMR of TNT and its metabolites was 7.8-1000 ng/mL. The method showed an excellent correlation (>0.99) for TNT and its metabolites. Accuracy and within/between day precision of TNT and its metabolites were within ±15%. The integrity of diluted samples was maintained for each dilution factor. The method was found stable after storage and freeze-thaw cycle. The presented method can be used for TNT screening in occupationally exposed ordnance factory workers.


Asunto(s)
Cromatografía Liquida/métodos , Espectrometría de Masas en Tándem/métodos , Trinitrotolueno/orina , Diseño de Equipo , Humanos , Trinitrotolueno/metabolismo
2.
Endocr J ; 69(1): 45-54, 2022 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-34305069

RESUMEN

A commutability confirmation test for the blood aldosterone measurement was performed on liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS) as a designated comparison method (DCM) and four chemiluminescent enzyme immunoassay (CLEIA) measurement procedures based on metrological traceability. A conventional radioimmunoassay (RIA) and two measurement procedures of CLEIA which obtains RIA equivalent values were also compared. The relationship between the DCM value and the CLEIA value with respect to 120 pg/mL of the RIA value, which is the screening criterion of primary aldosteronism (PA) was clarified. For the correlation test, 75 samples of patient serum and plasma were used. Regression analysis revealed that the standardized LC-MS/MS and four CLEIA measurement procedures were in good agreement. This is the effect of measurement specificity and calibration using by certified reference material (CRM). The median of the LC-MS/MS corresponding to 120 pg/mL of RIA was 48.5 pg/mL. In the mean of standardized four CLEIA values corresponding to the 48.5 pg/mL of LC-MS/MS value was 47.51 pg/mL and the standard deviation (SD) was 2.93 pg/mL. However, the correlation between the RIA value and the RIA equivalent of the two measurement procedures by CLEIA differed depending on the measurement procedure. This is due to the influence of RIA measurement performance. Standardized CLEIA measurements are suitable for routine measurement procedure. When converting the LC-MS/MS equivalent value by the standardized CLEIA to the conventional RIA value, it is necessary to use the conversion formula.


Asunto(s)
Aldosterona , Espectrometría de Masas en Tándem , Cromatografía Liquida/métodos , Humanos , Técnicas para Inmunoenzimas , Radioinmunoensayo/métodos , Espectrometría de Masas en Tándem/métodos
3.
J Cell Biochem ; 121(1): 125-134, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31232490

RESUMEN

Escherichia coli is frequently exploited for genetic manipulations and heterologous gene expression studies. We have evaluated the metabolic profile of E. coli strain BL21 (DE3) RIL CodonPlus after genetic modifications and subjecting to the production of recombinant protein. Three genetically variable E. coli cell types were studied, normal cells (susceptible to antibiotics) cultured in simple LB medium, cells harboring ampicillin-resistant plasmid pET21a (+), grown under antibiotic stress, and cells having recombinant plasmid pET21a (+) ligated with bacterial lactate dehydrogenase gene grown under ampicillin and standard isopropyl thiogalactoside (IPTG)-induced gene expression conditions. A total of 592 metabolites were identified through liquid chromatography-mass spectrometry/mass spectrometry analysis, feature and peak detection using XCMS and CAMERA followed by precursor identification by METLIN-based procedures. Overall, 107 metabolites were found differentially regulated among genetically modified cells. Quantitative analysis has shown a significant modulation in DHNA-CoA, p-aminobenzoic acid, and citrulline levels, indicating an alteration in vitamin K, folic acid biosynthesis, and urea cycle of E. coli cells during heterologous gene expression. Modulations in energy metabolites including NADH, AMP, ADP, ATP, carbohydrate, terpenoids, fatty acid metabolites, diadenosine tetraphosphate (Ap4A), and l-carnitine advocate major metabolic rearrangements. Our study provides a broader insight into the metabolic adaptations of bacterial cells during gene manipulation experiments that can be prolonged to improve the yield of heterologous gene products and concomitant production of valuable biomolecules.


Asunto(s)
Escherichia coli/metabolismo , Perfilación de la Expresión Génica , Regulación Bacteriana de la Expresión Génica , Metaboloma , Ácido 4-Aminobenzoico/farmacología , Ampicilina/farmacología , Antibacterianos/farmacología , Carbohidratos/química , Cromatografía por Intercambio Iónico , Cromatografía Liquida , Citrulina/metabolismo , Citrulina/farmacología , Codón , Coenzima A/metabolismo , Farmacorresistencia Bacteriana , Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Ácido Fólico/metabolismo , Isopropil Tiogalactósido/farmacología , Metabolómica , Oxo-Ácido-Liasas/metabolismo , Proteínas Recombinantes/metabolismo , Espectrometría de Masas en Tándem , Terpenos/metabolismo , Urea/metabolismo , Vitamina K/metabolismo
4.
Tumour Biol ; 41(3): 1010428319827223, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30907281

RESUMEN

Prostate cancer represents a major cause of cancer death in men worldwide. Novel non-invasive methods are still required for differentiation of non-aggressive from aggressive tumors. Recently, changes in prostate-specific antigen glycosylation pattern, such as core-fucosylation, have been described in prostate cancer. The objective of this study was to evaluate whether the core-fucosylation determinant of serum prostate-specific antigen may serve as refined marker for differentiation between benign prostate hyperplasia and prostate cancer or identification of aggressive prostate cancer. A previously developed liquid chromatography-mass spectrometry/mass spectrometry-based strategy was used for multiplex analysis of core-fucosylated prostate-specific antigen (fuc-PSA) and total prostate-specific antigen levels in sera from 50 benign prostate hyperplasia and 100 prostate cancer patients of different aggressiveness (Gleason scores, 5-10) covering the critical gray area (2-10 ng/mL). For identification of aggressive prostate cancer, the ratio of fuc-PSA to total prostate-specific antigen (%-fuc-PSA) yielded a 5%-8% increase in the area under the curve (0.60) compared to the currently used total prostate-specific antigen (area under the curve = 0.52) and %-free prostate-specific antigen (area under the curve = 0.55) tests. However, our data showed that aggressive prostate cancer (Gleason score > 6) and non-aggressive prostate cancer (Gleason score ≤ 6) could not significantly (p-value = 0.08) be differentiated by usage of %-fuc-PSA. In addition, both non-standardized fuc-PSA and standardized %-fuc-PSA had no diagnostic value for differentiation of benign prostate hyperplasia from prostate cancer. The %-fuc-PSA serum levels could not improve the differentiation of non-aggressive and aggressive prostate cancer compared to conventional diagnostic prostate cancer markers. Still, it is unclear whether these limitations come from the biomarker, the used patient cohort, or the imprecision of the applied method itself. Therefore, %-fuc-PSA should be further investigated, especially by more precise methods whether it could be clinically used in prostate cancer diagnosis.


Asunto(s)
Biomarcadores de Tumor/química , Antígeno Prostático Específico/química , Hiperplasia Prostática/diagnóstico , Hiperplasia Prostática/patología , Neoplasias de la Próstata/diagnóstico , Neoplasias de la Próstata/patología , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/sangre , Cromatografía Liquida , Diagnóstico Diferencial , Glicosilación , Humanos , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Próstata/patología , Antígeno Prostático Específico/sangre , Espectrometría de Masas en Tándem
5.
Alcohol Clin Exp Res ; 42(11): 2094-2099, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30091144

RESUMEN

BACKGROUND: The purpose of this study was to characterize the pharmacokinetics of the phosphatidylethanol (PEth) 16:0/20:4 homolog in uncoagulated human blood samples taken from 18 participants in a clinical laboratory setting after consumption of 2 standard doses of ethanol (EtOH). METHODS: Male and female participants received either 0.4 or 0.8 g/kg oral doses of EtOH during a 15-minute period. Blood samples were collected before and throughout 6 hours immediately after alcohol administration and then again at days 2, 4, 7, 11, and 14 of the follow-up period. PEth 16:0/20:4 levels were quantified by high-performance liquid chromatography with tandem mass spectrometry detection. RESULTS: (i) The increase in PEth 16:0/20:4 from baseline to maximum concentration was less than that of PEth 16:0/18:1 or PEth 16:0/18:2 homologs during the 6-hour period after EtOH administration; (ii) the mean half-life of PEth 16:0/20:4 was 2.1 ± 3 (SD) days, which was shorter than the mean half-life of either PEth 16:0/18:1 or PEth 16:0/18:2, 7.6 ± 3 (SD) or 6.8 ± 4 (SD) days, respectively. CONCLUSIONS: The pharmacokinetics of PEth 16:0/20:4 in whole blood samples is detectable after alcohol consumption and differs in amount synthesized and rate of elimination versus PEth 16:0/18:1 and 16:0/18:2. Measuring the concentrations of these 3 homologs has the potential to provide more information about the amount and time frame of alcohol consumption than any one alone.


Asunto(s)
Depresores del Sistema Nervioso Central/farmacología , Etanol/farmacología , Glicerofosfolípidos/sangre , Glicerofosfolípidos/farmacocinética , Adulto , Consumo de Bebidas Alcohólicas , Cromatografía Líquida de Alta Presión , Femenino , Semivida , Humanos , Masculino , Persona de Mediana Edad , Espectrometría de Masas en Tándem , Adulto Joven
6.
Chirality ; 30(3): 302-309, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29314267

RESUMEN

A supramolecular solvent composed of decanol in tetrahydrofuran/water was utilized for the simultaneous microextraction of chiral triadimefon and triadimenol in beer samples. Supramolecular solvents are nanostructured amphiphilic liquids that contain aqueous cavities, and the size of those cavities can be adjusted by the ratio of decanol, tetrahydrofuran, and water. The target analytes were mixed into the matrix sample and extracted in the supramolecular solvent phase, which was followed by separation and quantification by chiral liquid chromatography-mass spectrometry. The influences of some analytical parameters and matrix components were all examined. Under the optimized conditions, the method detection limits were in the range of 0.24 to 0.98 µg L-1 (at a signal/noise of 3), with relative standard deviations between 1.6 and 5.7%. The linearities of the calibration plots were between 0.5 to 50 (triadimenol) and 1.0 to 100 µg L-1 (triadimefon). When this method was applied to a spiked beer sample, the recoveries ranged from 84 to 100%.

7.
Ann Clin Biochem ; 61(5): 406-409, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38779860

RESUMEN

BACKGROUND: Non-alcoholic fatty liver disease is classified into simple steatosis (SS) and non-alcoholic steatohepatitis (NASH) according to histological findings from liver biopsies. Phosphatidylcholine (PC), the main component of phospholipids in serum lipoproteins, is easily oxidized to phosphatidylcholine hydroperoxide (PC-OOH). Although a lipid composition in the low-density lipoproteins (LDL) from patients with NASH could be abnormal, it remains unclear. Here, to better understand the characteristics of lipids in the LDL from NASH and SS, we compared the composition of PC and PC-OOH species in LDL particles (LDL-PC, LDL-PCOOH) from these patients, then clarified the association between these lipids and NASH severity. METHODS: The serum samples from patients with NASH (female, n = 9) and SS (female, n = 4; male, n = 2) were used for isolation of LDL. Total lipids were extracted from isolated LDL, and the species of PC and PC-OOH were measured using liquid chromatography-mass spectrometry/mass spectrometry. RESULTS: The sum of LDL-PC and the sum of LDL-PCOOH were significantly higher in NASH than in SS. Several LDL-PC (PC 32:0, 32:1, 32:2, 34:3, 36:2, sum of PC with saturated fatty acyl chains and sum of LDL-PC with polyunsaturated fatty acyl chains) and several LDL-PCOOH (34:2, 36:2, 36:3 and total) were increased significantly with increasing fibrosis score. In particular, a series of LDL-PCOOH were more reflective of the severity of fibrosis score. CONCLUSIONS: LDL-PC and LDL-PCOOH species were strongly correlated with the fibrosis score in NASH, which suggests that abnormal LDL is involved in the development of liver fibrosis.


Asunto(s)
Lipoproteínas LDL , Enfermedad del Hígado Graso no Alcohólico , Fosfatidilcolinas , Humanos , Femenino , Enfermedad del Hígado Graso no Alcohólico/sangre , Masculino , Fosfatidilcolinas/sangre , Lipoproteínas LDL/sangre , Persona de Mediana Edad , Adulto , Anciano
8.
Foods ; 13(12)2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38928829

RESUMEN

The purpose of this study was to evaluate and validate methylene blue migration from printed time-temperature indicators (TTIs) into food. It also highlights the importance of establishing regulatory measures and safety standards for food packaging, suggesting that this can contribute to improving food packaging safety. Liquid chromatography-mass spectrometry (LC-MS/MS) was used to quantify methylene blue migration in various food simulant and food matrix samples. The results show that the level of methylene blue migration varies significantly depending on the chemical properties of the food mimetic and the composition of the food matrix. The established method demonstrated a high sensitivity, with limits of detection (LODs) of 0.0019-0.0706 µg/L (kg) and limits of quantification (LOQs) of 0.0057-0.2138 µg/L (kg). This study highlights the need for a regulatory framework to mitigate the health risks associated with methylene blue in intelligent packaging systems and argues that regulatory thresholds should be set to ensure food safety and quality.

9.
Artículo en Inglés | MEDLINE | ID: mdl-36657458

RESUMEN

Pesticide use is indispensable for combating diseases occurring during olive cultivation. However, this has led to challenges of pesticide residues in consumer products as a result of pesticide application errors and the methods used during processing and preservation. This work aimed to identify the effects of table olive processing and preservation techniques on the concentrations of malathion and its degradation product malaoxon. For this purpose, olive trees in an experimental olive orchard were sprayed homogeneously with malathion at a dose of 975 mg L-1 and processed as (i) vacuum-packed, (ii) alkali treated and (iii) directly brined for natural fermentation. The changes in microbial growth, pH-acidity and pesticide (malathion and malaoxon) concentrations were monitored regularly during the experiment. Lactic acid bacteria, yeast and mould growth were not detected in any of the treatments. Mesophilic aerobic bacteria and enterobacteria were the dominant microbial groups in all non-sprayed treatments, but no enterobacteria growth was detected in sprayed treatments. Lower pH values were observed in the brines of natural fermentation treatments of both sprayed and non-sprayed olives. The independent effects of time and processing method and their interactions on malathion and malaoxon concentrations were found significant (p < .05). During the experiments, the highest reduction in malathion concentration was observed in alkali treated samples (95-99%), followed by naturally fermented (77-88%) and vacuum-packed samples (74-76%). Processing factors for all treatments were lower than 1.


Asunto(s)
Olea , Plaguicidas , Malatión , Fermentación
10.
Food Chem X ; 14: 100302, 2022 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-35434600

RESUMEN

Kombucha, originated in China 2000  years ago, is a sour and sweet-tasted drink, prepared traditionally through fermentation of black tea. During the fermentation of kombucha, consisting of mainly acidic compounds, microorganisms, and a tiny amount of alcohol, a biofilm called SCOBY forms. The bacteria in kombucha has been generally identified as Acetobacteraceae. Kombucha is a noteworthy source of B complex vitamins, polyphenols, and organic acids (mainly acetic acid). Nowadays, kombucha is tended to be prepared with some other plant species, which, therefore, lead to variations in its composition. Pre-clinical studies conducted on kombucha revealed that it has desired bioactivities such as antimicrobial, antioxidant, hepatoprotective, anti-hypercholestorelomic, anticancer, anti-inflammatory, etc. Only a few clinical studies have been also reported. In the current review, we aimed to overhaul pre-clinical bioactivities reported on kombucha as well as its brief compositional chemistry. The literature data indicate that kombucha has valuable biological effects on human health.

11.
Gynecol Minim Invasive Ther ; 10(4): 226-234, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34909380

RESUMEN

OBJECTIVES: Ovulation is such a critical physiological process that its noninvasive detection based on salivary constituents has several advantages in humans. Hence, the present study is proposed to identify the ovulatory-specific proteins in saliva in order to detect ovulation phase. MATERIALS AND METHODS: Samples were collected from women volunteers. The procedure adopted was approved by the Institutional Human Ethical Committee (DM/2014/101/38), Bharathidasan University. The saliva samples were collected from thirty healthy female volunteers, with a prior written consent. One-way analysis of variance was used to calculate protein concentration and band intensity using SPSS 16 software (SPSS Inc., Cary, NC, USA). The salivary protein expression pattern during different phases of menstrual cycle was analyzed using gel-based high resolution-liquid chromatography-mass spectrometry/mass spectrometry and matrix-assisted laser desorption ionization-time of flight/time of flight. Further, bioinformatics tools were adopted to annotate the proteins identified at various phases of menstrual cycle. RESULTS: As many as 530 proteins showed up in the saliva during ovulatory phase, whereas there were only 251 proteins identified during postovulatory phase. The functional annotation of salivary proteins revealed that the proteins got assigned to the class of "extracellular proteins" which are concerned with regulatory functions. The 16 unique and/or differentially expressed protein spots appeared during ovulatory phase, among which Cystatin-S, Prolactin-inducible protein, Cystatin-A, Cystatin-SN, BPI fold-containing family A member 2, Alpha-tubulin N-acetyltransferase 1, Carbonic anhydrase-6, Protein LEG1 homolog, Hemoglobin subunit beta, and Pancreatic alpha-amylase were identified. CONCLUSION: Total salivary proteome profile has been listed with respect to various phases of menstrual cycle. Among the protein listed, Cystatin-S offers a biomarker protein and/or indicator of ovulatory phase. However, extensive validation is required before arriving to a candidate bio-marker protein.

12.
J Forensic Sci ; 66(1): 272-277, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33027535

RESUMEN

Testing for drugs in hair raises several difficulties. Among them is the interpretation of the final concentration(s). In a post-mortem case, analyses revealed the presence of furosemide (12 ng/mL) in femoral blood, although it was not part of the victim's treatment. The prosecutor requested our laboratory to undertake an additional analysis in hair to obtain information about the use of furosemide. A specific method was therefore developed and validated to identify and quantify furosemide in hair by UHPLC-MS/MS. After decontamination of 30 mg of hair, incubation in acidic condition, extraction with ethyl acetate, the samples were analyzed by UHPLC-MS/MS. Furosemide was found in the victim's hair at 225 pg/mg. However, it was not possible to interpret this concentration due to the absence of data in the literature. Therefore, the authors performed a controlled study in two parts. In order to establish the basis of interpretation, several volunteers were tested (four after a single 20 mg administration and twenty-four under daily treatment). The first part indicated that a single dose is not detectable in hair using our method. The second part demonstrated concentrations ranging from 5 to 1110 pg/mg with no correlation between dosage and hair concentrations. The decedent's hair result was interpreted as repeated exposures. In the case of furosemide analysis, hair can provide information about its presence but cannot give information about dosage or frequency of use.


Asunto(s)
Diuréticos/análisis , Furosemida/análisis , Cabello/química , Anciano , Anciano de 80 o más Años , Cromatografía Líquida de Alta Presión , Femenino , Toxicología Forense/métodos , Humanos , Masculino , Espectrometría de Masas , Persona de Mediana Edad
13.
Toxicol Rep ; 8: 1657-1664, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34584850

RESUMEN

The current study sought to assess the residual levels of neonicotinoid insecticides (NEO) in organic and conventional green tea leaves produced in Japan. A total of 103 tea leaves (thus, 42 organic and 61 conventional), were sampled from grocery stores in Japan. Concentrations of NEOs in the tea leaves were quantified using LC-MS/MS; and the data was used to estimate maximum daily intakes of NEOs within the Japanese population. Seven native NEO compounds and one NEO metabolite were detected in both organic and conventional tea leaves. Detection frequencies (%Dfs) of NEOs in the tea samples (n = 103) were found in the decreasing order; thiacloprid (84.47 %) > dinotefuran (74.76 %) > imidacloprid (69.90 %) ≈ clothianidin (69.90 %) > dm-acetamiprid (63.11 %) > thiamethoxam (58.25 %) > acetamiprid (4.85 %) > nitenpyram (1.94 %). About 94.20 % of the tea leaves contained two or more NEO compounds simultaneously. The %Dfs of NEOs were relatively lower in organic tea leaves, compared to the conventional tea leaves. Various percentile concentrations of NEOs were far lower in organic tea leaves, compared to the conventional tea leaves. The maximum daily intakes of NEOs through consumption of tea (MDIgt) were also lower for organic tea leaves, compared to the conventional tea samples.

14.
J Bone Oncol ; 26: 100337, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33240786

RESUMEN

Breast cancer (BC) is the most frequent malignancy and the first cause of cancer-related death in women. The majority of patients with advanced BC develop skeletal metastases which may ultimately lead to serious complications, termed skeletal-related events, that often dramatically impact on quality of life and survival. Therefore, the identification of biomarkers able to stratify BC patient risk to develop bone metastases (BM) is fundamental to define personalized diagnostic and therapeutic strategies, possibly at the earliest stages of the disease. In this regard, the advent of "omics" sciences boosted the investigation of several putative biomarkers of BC osteotropism, including deregulated genes, proteins and microRNAs. The present review revisits the current knowledge on BM development in BC and the most recent studies exploring potential BM-predicting biomarkers, based on the application of omics sciences to the study of primary breast malignancies.

15.
Data Brief ; 31: 105860, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32637480

RESUMEN

Patient-derived scaffolds (PDSs) generated from primary breast cancer tumors can be used to model the tumor microenvironment in vitro. Patient-derived scaffolds are generated by repeated detergent washing, removing all cells. Here, we analyzed the protein composition of 15 decellularized PDSs using liquid chromatography-mass spectrometry/mass spectrometry. One hundred forty-three proteins were detected and their relative abundance was calculated using a reference sample generated from all PDSs. We performed heatmap analysis of all the detected proteins to display their expression patterns across different PDSs together with pathway enrichment analysis to reveal which processes that were connected to PDS protein composition. This protein dataset together with clinical information is useful to investigators studying the microenvironment of breast cancers. Further, after repopulating PDSs with either MCF7 or MDA-MB-231 cells, we quantified their gene expression profiles using RNA sequencing. These data were also compared to cells cultured in conventional 2D conditions, as well as to cells cultured as xenografts in immune-deficient mice. We investigated the overlap of genes regulated between these different culture conditions and performed pathway enrichment analysis of genes regulated by both PDS and xenograft cultures compared to 2D in both cell lines to describe common processes associated with both culture conditions. Apart from our described analyses of these systems, these data are useful when comparing different experimental model systems. Downstream data analyses and interpretations can be found in the research article "Patient-derived scaffolds uncover breast cancer promoting properties of the microenvironment" [1].

16.
J Adv Pharm Technol Res ; 11(4): 207-212, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33425706

RESUMEN

A reliable method has been validated using ultra-performance liquid chromatography mass spectrometry (MS)/MS for simultaneous evaluation of human plasma concentration of mycophenolic acid (MPA) and its major metabolites both total and free form. All analytes were extracted from plasma by simple protein precipitation procedure with methanol. Samples for determination of their free form concentration require a preanalytic spin through an ultrafiltration system. The chromatographic separation was completed using C18column at 0.3 ml/min with a gradient condition. Method validation was performed as the United State Food and Drug Administration guidelines for bio-analytical methods concerning precision, accuracy, linearity, selectivity, recovery, and matrix effect. Linearity was obtained over concentration of 0.05-4, 0.5-60, and 0.025-3 µg/ml for total MPA, mycophenolic acid glucuronide (MPAG) and mycophenolic acid acyl-glucuronide (AcMPAG), respectively. The linearity of the method for free form of analytes was confirmed in the range of 10-500, 125-10,000, and 0.5-300 ng/ml for MPA, MPAG, and AcMPAG, respectively. The intra- and interday accuracy ranged from 85.73%-102.01% for total form, and 87.23%-111.89% for free form, and the precisions of all analytes were lower than 15%. The mean recoveries of the analytes ranged from 85.54% to 94.76% and the matrix factor ranged from 0.88-1.06. The developed method is rapid, sensitive and convenient for pharmacokinetic study or therapeutic drug monitoring in patients after oral administration of enteric-coated mycophenolate sodium or mycophenolate mofetil.

17.
J Chromatogr A ; 1625: 461294, 2020 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-32709337

RESUMEN

It is significant to precisely isolate potential active compounds from medicinal herbs containing multiple compounds. Herein, a new strategy for precise separation of lysine-specific demethylase 1 (LSD1) inhibitors from the rhizome of Corydalis yanhusuo (RCY) using counter-current chromatography (CCC) guided by molecular docking and liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS) analysis was established. First, representative alkaloids from RCY were docked with LSD1 for screening active skeleton compounds. Simultaneously, the crude extract of RCY was preliminarily separated via pH-zone refining CCC. Subsequently, guided by LC-MS/MS analysis of the fragmentation pathways, three potential active fractions were obtained, followed by further online-storage and recycling CCC separation. Finally, three high-purity target quaternary alkaloids compound 3 (dehydrocorydaline), 7 (coptisine), and 8 (columbamine) were successfully isolated as a new class of potential natural LSD1 inhibitors by only one CCC instrument with multiple modes. Compound 3, with the highest LSD1 inhibition ratio of 2.44 µM, was tested for its ability to inhibit tumor invasion and metastasis in U2OS cells. Therefore, the CCC separation guided by virtual screening is a promising method for the targeted isolation of enzyme inhibitors from medicinal herbs.


Asunto(s)
Corydalis/química , Distribución en Contracorriente/métodos , Evaluación Preclínica de Medicamentos , Inhibidores Enzimáticos/aislamiento & purificación , Histona Demetilasas/antagonistas & inhibidores , Interfaz Usuario-Computador , Bioensayo , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Cromatografía Líquida de Alta Presión , Inhibidores Enzimáticos/química , Histona Demetilasas/metabolismo , Humanos , Concentración de Iones de Hidrógeno , Simulación del Acoplamiento Molecular , Solventes , Espectrometría de Masas en Tándem
18.
Toxicon X ; 8: 100062, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33163957

RESUMEN

Spiders use their venom for defence and to capture prey. These venoms contain a cocktail of biologically active compounds that display several different biological activities, such as large molecules and small molecules including peptides, proteins/enzymes, and other components. Thus, venom constituents have attracted the attention of biochemists and pharmacologists over the years. The brown widow spider (Latrodectus geometricus) is a venomous spider found worldwide, including in Thailand. This spider causes human injuries, and the venom has many potential applications. In this study, we investigated the complexity and pharmacology of brown widow spider venom. Spider crude venom was investigated using partial proteome techniques and enzymatic activity, toxicity, and antibacterial activity assessments. We found that crude venom displayed a wide range of molecular masses from 19 to over 97 kDa, with molecular masses of 66 kDa intensely stained. Peptides and proteins were identified by liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS), which showed that the crude venom contained a variety of substances, including latrotoxins, apolipophorins, hemocyanins, chitinases, arginine kinase, allergen antigen 5-like protein, astacin-like metalloproteases, and serine proteases. High hyaluronidase activity was observed based on the turbidimetric method. The venom presented toxicity in crickets (PD50 = 0.73 ± 0.10 µg/g body weight), and substantial envenomation symptoms, such as slow-motion movement, paralysis, and even death, were noted. Moreover, this venom exhibited potential antibacterial activity against the gram-positive Bacillus subtilis but not the gram-negative Pseudomonas aeruginosa. Spider venom contains numerous molecules with biological activity, such as latrotoxins, which affect insects, and enzymes. In addition to latrotoxins, certain enzymes in venom are hypothesized to exhibit toxicity and antimicrobial activity. This study provides important information for the further development of natural compounds or insecticidal toxins.

19.
J Forensic Sci ; 64(2): 643-646, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30132893

RESUMEN

In several medico-legal cases, bone samples analysis may provide the only source of toxicological information. This case study reports the analysis of a human bone specimen, belonging to a 46-year-old man, found 3 months after his death due to cervical-thoracic injuries in a motorcycle accident. Bone specimen was the only available material for toxicological analysis, among few skull hair and rotten skin. Analysis was performed by a newly developed and validated ultra-high-pressure liquid chromatography-mass spectrometry/mass spectrometry (UHPLC-MS/MS) method, following simple and efficient sample pretreatment. The results were in accordance with the man's medical record: Alprazolam and zolpidem were found at 2.2 and 5.4 ng/g of bone, respectively. Both these drugs were prescribed to the deceased.


Asunto(s)
Alprazolam/análisis , Restos Mortales , Cambios Post Mortem , Detección de Abuso de Sustancias , Zolpidem/análisis , Accidentes de Tránsito , Cromatografía Líquida de Alta Presión , Fémur/química , Cabello/química , Humanos , Hipnóticos y Sedantes/análisis , Masculino , Espectrometría de Masas , Persona de Mediana Edad , Motocicletas , Piel/química , Trastornos Relacionados con Sustancias/diagnóstico
20.
Transl Cancer Res ; 8(6): 2371-2379, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35116989

RESUMEN

BACKGROUND: Targeted metabolomics was utilized in case studies of non-small cell lung cancer (NSCLC) to develop and test metabolite classifiers in serum as potential biomarkers for new lung cancer diagnostic strategies, cancer staging, and subtype determination in the Chinese population. METHODS: A total of 77 samples, including 45 NSCLC patients from stage I to IV, and 32 healthy controls were included in this study. After serum extraction, metabolic assays based on a wide range of targeted metabolome technologies and the UPLC-MS-MS detection platform were performed to detect metabolites in them. Custom database and multivariate statistical analysis were utilized to evaluate the difference of metabolome between different arms. RESULTS: A total of 296 metabolites were detected in all samples, of which 81 were found differentially expressed among lung cancer patients and controls. While the principal component analysis indicated that the metabolome analysis is clearly powerful in differentiating lung cancer patients from normal controls, no significant differences in the serum metabolites between different lung cancer stages or between adenocarcinoma and squamous cell carcinoma were observed. CONCLUSIONS: This study showed the power of the novel UPLC-MS/MS platform in serum metabolic profiling for the detection of NSCLC, which might provide new potential tumor biomarkers and can accelerate the development of new diagnostic strategies in NSCLC.

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