Epilepsy, affecting over 50 million people globally, presents a significant neurological challenge. Effective prevention of epileptic seizures relies on proper administration and monitoring of Anti-Seizure Medication (ASMs). Therapeutic Drug Monitoring (TDM) ensures optimal dosage adjustment, minimizing adverse effects and potential drug interactions. While traditional venous blood collection for TDM may be stressful, emerging alternative sampling methods, particularly Dried Blood Spot (DBS) or oral fluid offer less invasive way of sampling. This study aimed to develop and validate an analytical method for the determination of lamotrigine in such alternative samples. The sample, either DBS or oral fluid, was subjected to extraction, evaporation, and reconstitution in 15 % acetonitrile containing 0.1 % formic acid. A Kinetex C18 Polar column was used for liquid chromatographic separation and MS in ESI+ mode was used for detection and quantitation of lamotrigine using an isotopically labelled internal standard according to EMA guidelines. The calibration range of the developed method enables the determination of lamotrigine in the concentration range of 1-30 μg/mL in DBS and 0.5-20 μg/mL in oral fluid. Oral fluid and DBS samples from patients treated with lamotrigine analysed by the developed method were compared to plasma concentrations measured by the hospital's accredited laboratory. Preliminary results indicate a promising potential for these alternative matrices in clinical TDM applications. By offering a less invasive sampling approach, this method improves the accessibility and safety of pharmacotherapy for epilepsy patients. The results of this study lay the foundation for further clinical applications by implementing alternative matrix TDM, which may significantly advance personalized care in epilepsy management.
- MeSH
- Anticonvulsants * analysis blood MeSH
- Chromatography, Liquid methods MeSH
- Epilepsy drug therapy MeSH
- Calibration MeSH
- Liquid Chromatography-Mass Spectrometry MeSH
- Lamotrigine * analysis blood MeSH
- Humans MeSH
- Limit of Detection MeSH
- Drug Monitoring * methods MeSH
- Reproducibility of Results MeSH
- Saliva * chemistry MeSH
- Tandem Mass Spectrometry methods MeSH
- Dried Blood Spot Testing * methods MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Validation Study MeSH
The semi-synthetic cannabinoid hexahydrocannabinol (HHC) has become a highly discussed topic in forensic toxicology since 2022 due to its legal availability at this time and its psychoactive effects. This study aimed to investigate the pharmacokinetics, effects, and immunological detectability of HHC after oral (25 mg HHC fruit gum) and inhalative (three puffs from HHC vape) consumption with three participants per group. Serum (up to 48 h), urine (up to five days), and saliva (up to 48 h) samples were collected at different relevant time points and analyzed by HPLC-MS/MS for (9R)/(9S)-HHC, 11-hydroxy-HHC, and (9R)/(9S)-HHC carboxylic acid with a fully validated method. Additionally, immunological detectability was investigated with three different commercially available tests. To address the psychoactive effects, the subjective "high" feeling (scale 0-10) was monitored and different psychophysical tests (e.g. modified Romberg test, walk and turn) were conducted. Overall, the pharmacokinetics and effects of HHC were comparable to tetrahydrocannabinol (THC). However, the route of administration as well as inter-individual factors played a crucial role regarding maximum concentrations, pharmacokinetic profiles, and psychoactive effects.
- MeSH
- Cannabinoid Receptor Agonists pharmacokinetics pharmacology MeSH
- Administration, Inhalation * MeSH
- Administration, Oral * MeSH
- Adult MeSH
- Emotions drug effects MeSH
- Pharmacokinetics * MeSH
- Immunologic Tests MeSH
- Cannabinoids * analysis blood pharmacokinetics pharmacology urine MeSH
- Liquid Chromatography-Mass Spectrometry MeSH
- Humans MeSH
- Psychophysiology * MeSH
- Psychotropic Drugs * analysis blood pharmacokinetics pharmacology urine MeSH
- Saliva chemistry MeSH
- Dronabinol pharmacokinetics pharmacology MeSH
- Check Tag
- Adult MeSH
- Humans MeSH
- Male MeSH
- Female MeSH
- Publication type
- Journal Article MeSH
The precise and unambiguous detection and quantification of internal RNA modifications represents a critical step for understanding their physiological functions. The methods of direct RNA sequencing are quickly developing allowing for the precise location of internal RNA marks. This detection is, however, not quantitative and still presents detection limits. One of the biggest remaining challenges in the field is still the detection and quantification of m6A, m6Am, inosine, and m1A modifications of adenosine. The second intriguing and timely question remaining to be addressed is the extent to which individual marks are coregulated or potentially can affect each other. Here, we present a methodological approach to detect and quantify several key mRNA modifications in human total RNA and in mRNA, which is difficult to purify away from contaminating tRNA. We show that the adenosine demethylase FTO primarily targets m6Am marks in noncoding RNAs in HEK293T cells. Surprisingly, we observe little effect of FTO or ALKBH5 depletion on the m6A mRNA levels. Interestingly, the upregulation of ALKBH5 is accompanied by an increase in inosine level in overall mRNA.
- MeSH
- Adenosine * analogs & derivatives metabolism genetics analysis MeSH
- AlkB Homolog 5, RNA Demethylase * metabolism genetics MeSH
- Chromatography, Liquid methods MeSH
- Alpha-Ketoglutarate-Dependent Dioxygenase FTO * metabolism genetics MeSH
- HEK293 Cells MeSH
- Inosine * metabolism genetics MeSH
- Liquid Chromatography-Mass Spectrometry MeSH
- Humans MeSH
- RNA, Messenger * genetics metabolism MeSH
- RNA Processing, Post-Transcriptional MeSH
- Tandem Mass Spectrometry * methods MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
Východiska: Hledání účinných biomarkerů pro včasnou diagnostiku ovariálního karcinomu (ovarian cancer – OC) patří k naléhavým úkolům moderní onkogynekologie. Metabolické profilování pomocí ultra vysokoúčinné kapalinové chromatografie a hmotnostní spektrometrie (ultraigh performance liquid chromatography and mass spectrometry – UHPLC-MS) poskytuje informace o souhrnu všech nízkomolekulárních metabolitů vzorku biologických tekutin pacienta, které odrážejí procesy probíhající v těle. Cílem studie bylo prozkoumat metabolomický profil krevní plazmy a moči pacientek se serózním ovariálním adenokarcinomem pomocí UHPLC-MS. Materiál a metody: K provedení metabolomické analýzy bylo odebráno 60 vzorků krevní plazmy a 60 vzorků moči pacientek s diagnózou serózního karcinomu vaječníků a 20 vzorků zdravých dobrovolníků. Chromatografická separace byla provedena na chromatografu Vanquish Flex UHPLC System (Thermo Scientific, Německo). Analýza hmotnostní spektrometrií byla provedena na Orbitrap Exploris 480 (Thermo Scientific, Německo) vybaveném elektrosprejovým ionizačním zdrojem. Bioinformatická analýza byla provedena pomocí Compound Discoverer Software (Thermo Fisher Scientific, USA), statistická analýza dat byla provedena v programovacím jazyce Python pomocí knihovny SciPy. Výsledky: Pomocí UHPLC-MS bylo v krevní plazmě identifikováno 1 049 metabolitů různých tříd. U pacientek s OC mělo 8 metabolitů významně nižší koncentraci (p < 0,01) ve srovnání se zdravými dárci, zatímco u 19 látek byly zjištěny vyšší hladiny (p < 0,01). Během metabolomického profilování vzorků moči bylo identifikováno 417 metabolitů: 12 látek mělo významně nižší koncentraci ve srovnání se zjevně zdravými jedinci a u 14 látek byly hladiny vyšší (p < 0,01). U pacientek se serózním adenokarcinomem vaječníků byla zjištěna významná změna v metabolomu krevní plazmy a moči, vyjádřená abnormálními koncentracemi lipidů a jejich derivátů, mastných kyselin a jejich derivátů, acylkarnitinů, fosfolipidů, aminokyselin a jejich derivátů, derivátů dusíkatých bází a steroidů. Mezi nejslibnější markery tohoto onemocnění přitom patří kynurenin, kyselina myristová, lysofosfatidylcholin a L-oktanoylkarnitin. Závěr: Odhalené změny v metabolomu se mohou stát základem pro zlepšení přístupů k diagnostice serózního ovariálního adenokarcinomu.
Background: The search for effective biomarkers for ovarian cancer (OC) early diagnosis is an urgent task of modern oncogynecology. Metabolic profiling by ultra-high performance liquid chromatography and mass spectrometry (UHPLC-MS) provides information on the totality of all low molecular weight metabolites of patient’s biological fluids sample, reflecting the processes occurring in the body. The aim of the study was to research blood plasma and urine metabolomic profile of patients with serous ovarian adenocarcinoma by UHPLC-MS. Material and methods: To perform metabolomic analysis, 60 blood plasma samples and 60 urine samples of patients diagnosed with serous ovarian carcinoma and 20 samples of apparently healthy volunteers were taken. Chromatographic separation was performed on a Vanquish Flex UHPLC System chromatograph (Thermo Scientific, Germany). Mass spectrometric analysis was performed on an Orbitrap Exploris 480 (Thermo Scientific, Germany) equipped with an electrospray ionization source. Bioinformatic analysis was performed using Compound Discoverer Software (Thermo Fisher Scientific, USA), statistical data analysis was performed in the Python programming language using the SciPy library. Results: Using UHPLC-MS, 1,049 metabolites of various classes were identified in blood plasma. In patients with OC, 8 metabolites had a significantly lower concentration (P < 0.01) compared with conditionally healthy donors, while the content of 19 compounds, on the contrary, increased (P < 0.01). During the metabolomic profiling of urine samples, 417 metabolites were identified: 12 compounds had a significantly lower concentration compared to apparently healthy individuals, the content of 14 compounds increased (P < 0.01). In patients with ovary serous adenocarcinoma, a significant change in the metabolome of blood plasma and urine was found, expressed in abnormal concentrations of lipids and their derivatives, fatty acids and their derivatives, acylcarnitines, phospholipids, amino acids and their derivatives, derivatives of nitrogenous bases and steroids. At the same time, kynurenine, myristic acid, lysophosphatidylcholine and L-octanoylcarnitine are the most promising markers of this disease. Conclusion: The revealed changes in the metabolome can become the basis for improving approaches to the diagnosis of serous ovarian adenocarcinoma.
While the use of food additives is common manufacturing practice, the levels used in food have to be compliant with the prescribed legislation. For fast control of present levels of food additives in products, ultra-high performance liquid chromatography coupled to tandem mass spectrometry with a triple quadrupole linear ion trap (QTRAP) mass analyser was applied to develop a method for the simultaneous determination of 41 frequently added food additives and flavourings, including 16 water-soluble colourants, 14 illegal dyes, 7 sweeteners, 2 preservatives, and 2 purine alkaloids. The method was validated using energy drink, chilli powder, condiment, and jelly sweets as food sample matrices. The average recovery values were in the range of 70‒120%, and the relative standard deviations were less than 10% for the majority of the analytes. The validated method was applied for the analysis of 134 samples from the Czech market.
- MeSH
- Food Analysis * methods MeSH
- Flavoring Agents analysis MeSH
- Liquid Chromatography-Mass Spectrometry MeSH
- Food Contamination * analysis MeSH
- Humans MeSH
- Limit of Detection MeSH
- Beverages * analysis MeSH
- Food Additives * analysis MeSH
- Reproducibility of Results MeSH
- Tandem Mass Spectrometry methods MeSH
- Chromatography, High Pressure Liquid MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Validation Study MeSH
- Geographicals
- Czech Republic MeSH
Microflow liquid chromatography interfaced with mass spectrometry (μLC-MS/MS) is increasingly applied for high-throughput profiling of biological samples and has been proven to have an acceptable trade-off between sensitivity and reproducibility. However, lipidomics applications are scarce. We optimized a μLC-MS/MS system utilizing a 1 mm inner diameter × 100 mm column coupled to a triple quadrupole mass spectrometer to establish a sensitive, high-throughput, and robust single-shot lipidomics workflow. Compared to conventional lipidomics methods, we achieve a ∼4-fold increase in response, facilitating quantification of 351 lipid species from a single iPSC-derived cerebral organoid during a 15 min LC-MS analysis. Consecutively, we injected 303 samples over ∼75 h to prove the robustness and reproducibility of the microflow separation. As a proof of concept, μLC-MS/MS analysis of Alzheimer's disease patient-derived iPSC cerebral organoid reveals differential lipid metabolism depending on APOE phenotype (E3/3 vs E4/4). Microflow separation proves to be an environmentally friendly and cost-effective method as it reduces the consumption of harmful solvents. Also, the data demonstrate robust, in-depth, high-throughput performance to enable routine clinical or biomedical applications.
- MeSH
- Apolipoproteins E MeSH
- Chromatography, Liquid methods MeSH
- Phenotype MeSH
- Liquid Chromatography-Mass Spectrometry * MeSH
- Humans MeSH
- Lipidomics MeSH
- Reproducibility of Results MeSH
- Tandem Mass Spectrometry * methods MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
Galactooligosaccharides (GOS) are lactose-derived functional ingredients applied in food products and have great potential in health protection. The conversion of lactose to GOS commonly occurs using β-galactosidases of mould, yeast and bacterial origin. The yield and structure of the resulting GOS depend on the enzyme used and the reaction conditions. This work focuses on the structural analysis of the products obtained with four commercial β-galactosidases Maxilact LGI 5000 (ML), Maxilact A4 MG (MA), Saphera 2600 L (SA) and NOLA Fit 5500 (NL) to evaluate their efficiency and specificity. HPLC, ESI-MS and NMR spectroscopy were applied to characterise the GOS preparations. GOS were separated from the reaction mixture using activated charcoal treatment. HPLC analysis confirmed that most of the monosaccharides and a part of the lactose, but also some other disaccharides, probably allolactose and 6-galactobiose, were retained by charcoal. In all the products, ESI-MS analysis detects oligosaccharides up to hexamers. NMR spectra confirmed the presence of GOS of various configurations and polymerisation degrees and evaluated the specificity of used enzymes. MA preferably forms 1,6- and 1,4-glycosidic bonds, and bacterial enzymes NL and SA also form 1,2- and 1,3- glycosidic bonds, while yeast enzyme ML cannot produce new 1,4-glycosidic bonds. The mould enzyme MA showed the highest trans-galactosylation activity, forming longer GOS oligomers than the other enzymes.
- MeSH
- beta-Galactosidase * metabolism chemistry MeSH
- Galactose chemistry metabolism MeSH
- Spectrometry, Mass, Electrospray Ionization * methods MeSH
- Lactose metabolism chemistry MeSH
- Magnetic Resonance Spectroscopy * methods MeSH
- Oligosaccharides * chemistry metabolism MeSH
- Chromatography, High Pressure Liquid methods MeSH
- Publication type
- Journal Article MeSH
- Comparative Study MeSH
The increasing contamination of cereals by micromycetes and mycotoxins during malting still poses an unresolved food safety problem. This study characterises the potential of the novel, rapidly developing food production technology of Pulsed Electric Field (PEF) to reduce the viability of Fusarium fungi and the production of mycotoxins during malting. Barley, artificially inoculated with four Fusarium species, was treated by PEF with two different intensities and then malted using a standard Pilsner-type technology. Concentrations of fungi were quantified by RT-PCR, expression of fungal growth-related genes was assessed using mRNA sequencing, and mycotoxin levels were analysed by U-HPLC-HRMS/MS. Despite the different trends for micromycetes and mycotoxins after application of variously intense PEF conditions, significant reductions were generally observed. The greatest decrease was for F. sporotrichioides and F. poae, where up to six fold lower levels were achieved for malts produced from the PEF-treated barley when compared to the control. For F. culmorum and F. graminearum, up to a two-fold reduction in the PEF-generated malts was observed. These reductions mostly correlated with a decrease in relevant mycotoxins, specifically type A trichothecenes.
- MeSH
- Electricity MeSH
- Fusarium * metabolism genetics growth & development MeSH
- Hordeum * microbiology MeSH
- Edible Grain * microbiology MeSH
- Food Contamination prevention & control MeSH
- Food Handling methods MeSH
- Mycotoxins * biosynthesis metabolism MeSH
- Food Microbiology MeSH
- Publication type
- Journal Article MeSH
As organoids and organ-on-chip (OoC) systems move toward preclinical and clinical applications, there is an increased need for method validation. Using a liquid chromatography-mass spectrometry (LC-MS)-based approach, we developed a method for measuring small-molecule drugs and metabolites in the cell medium directly sampled from liver organoids/OoC systems. The LC-MS setup was coupled to an automatic filtration and filter flush system with online solid-phase extraction (SPE), allowing for robust and automated sample cleanup/analysis. For the matrix, rich in, e.g., protein, salts, and amino acids, no preinjection sample preparation steps (protein precipitation, SPE, etc.) were necessary. The approach was demonstrated with tolbutamide and its liver metabolite, 4-hydroxytolbutamide (4HT). The method was validated for analysis of cell media of human stem cell-derived liver organoids cultured in static conditions and on a microfluidic platform according to Food and Drug Administration (FDA) guidelines with regards to selectivity, matrix effects, accuracy, precision, etc. The system allows for hundreds of injections without replacing chromatography hardware. In summary, drug/metabolite analysis of organoids/OoCs can be performed robustly with minimal sample preparation.
- MeSH
- Chromatography, Liquid methods MeSH
- Solid Phase Extraction MeSH
- Mass Spectrometry methods MeSH
- Liver * metabolism MeSH
- Liquid Chromatography-Mass Spectrometry MeSH
- Small Molecule Libraries analysis metabolism chemistry MeSH
- Lab-On-A-Chip Devices MeSH
- Pharmaceutical Preparations metabolism analysis MeSH
- Humans MeSH
- Organoids * metabolism cytology MeSH
- Tolbutamide metabolism analysis MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Validation Study MeSH
Saxitoxins (STXs) are potent neurotoxins produced by marine dinoflagellates or freshwater cyanobacteria known to cause acute and eventually fatal human intoxications, which are classified as paralytic shellfish poisonings (PSPs). Rapid analysis of STXs in blood plasma can be used for a timely diagnosis and confirmation of PSPs. We developed a fast and simple method of STX extraction based on plasma sample acidification and precipitation by acetonitrile, followed by quantification using liquid chromatography-tandem mass spectrometry (LC-MS-MS). Our approach provides the results ≤30 min, with a limit of detection of 2.8 ng/mL and a lower limit of quantification of 5.0 ng/mL. Within-run and between-run precision experiments showed good reproducibility with ≤15% values. Standard curves for calibration were linear with correlation coefficients ≥0.98 across the assay calibration range (5-200 ng/mL). In an interlaboratory analytical exercise, the method was found to be 100% accurate in determining the presence or absence of STX in human plasma specimens, with recovery values of 86-99%. This simple method for STX determination in animal or human plasma can quickly and reliably diagnose STX exposures and confirm suspected PSP cases to facilitate patient treatment or expedite necessary public health or security actions.
