Retention-time prediction
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Para Red (PR) and Sudan dyes have been illegally used as colorants to adulterate certain foods by enhancing their red/orange colour. In addition, they are toxic and carcinogenic. This work presents the development of a simple flow injection chromatographic method combined with chemometric tools to perform the determination of PR, Sudan I (SI) and Sudan II (SII) in food samples. The flow chromatographic system consisted of a low-pressure manifold coupled to a reverse phase monolithic column. A Partial Least Square (PLS) model was applied to resolve overlapped absorption spectra registered for each dye at the corresponding retention time. The relative errors of calibration (RMSECV, %) were 0.49, 0.85 and 0.23, and the relative errors of prediction (RMSEP, %) were 1.12, 0.75 and 0.33 for PR, SI and SII, respectively. The residual predictive deviation (RPD) values obtained were higher than 3.00 for all analytes. The method was successfully applied to quantify the dyes in six different commercial spices samples. The results were compared with the HPLC reference method concluding that there were no significant differences at the studied confidence level (α = 0.05). The proposed method can be used to rapidly determine the analytes in a simple, reliable, low-cost and environmentally-friendly manner.Supplementary Information: The online version contains supplementary material available at 10.1007/s13197-021-05299-8.
- Publikační typ
- časopisecké články MeSH
Analysis of protein glycosylation is challenging due to micro- and macro-heterogeneity of the attached glycans. Hydrophilic interaction liquid chromatography (HILIC) is a mode of choice for separation of intact glycopeptides, which are inadequately resolved by reversed phase chromatography. In this work, we propose an easy-to-use model to predict retention time windows of glycopeptides in HILIC. We constructed this model based on the parameters derived from chromatographic separation of six differently glycosylated peptides obtained from tryptic digests of three plasma proteins: haptoglobin, hemopexin, and sex hormone-binding globulin. We calculated relative retention times of different glycoforms attached to the same peptide to the bi-antennary form and showed that the character of the peptide moiety did not significantly change the relative retention time differences between the glycoforms. To challenge the model, we assessed chromatographic behavior of fetuin glycopeptides experimentally, and their retention times all fell within the calculated retention time windows, which suggests that the retention time window prediction model in HILIC is sufficiently accurate. Relative retention time windows provide complementary information to mass spectrometric data, and we consider them useful for reliable determination of protein glycosylation in a site-specific manner.
Arteriální hypertenze (AH) a obezita patří mezi šestici nejvýznamnějších rizikových faktorů, které vedou k úmrtí ve světě. Oba rizikové faktory zvyšují riziko nejenom kardiovaskulárních onemocnění, ale i riziko nádorů a chronického ledvinového onemocnění. Existuje úzké obousměrné propojení obezity a AH. Obezita zvyšuje riziko vzniku AH dvoj- až trojnásobně a u obézních pacientů bývá obtížnější dosáhnout kontroly tlaku krve. Na druhé straně pozitivní rodinná anamnéza AH predikuje vznik centrální obezity. Současně osoby s vyšším krevním tlakem mají vyšší riziko vzestupu hmotnosti než osoby s nižším tlakem. Ústředním motivem elevace krevního tlaku při obezitě je zvýšená retence sodíku a vody způsobená aktivací systému renin‐angiotenzin a zvýšenou aktivitou sympatiku. Recentní analýza dat z reálné praxe poukazuje na účinnost, bezpečnost a metabolickou neutralitu fixní kombinace Perindopril/Indapamid u osob s AH a obezitou, diabetes mellitus 2. typu nebo metabolickým syndromem.
Arterial hypertension (AH) and obesity are among the six most important risk factors leading to death in the world. Both risk factors increase the risk not only of cardiovascular disease, but also the risk of cancer and chronic kidney disease. There are close two-way links between obesity and AH. Obesity increases the risk of developing AH two to threefold and in obese patients, blood pressure control is more difficult to achieve. On the other hand, a positive family history of AH predicts development of central obesity. At the same time, people with higher blood pressure have a higher risk of weight gain than people with lower blood pressure. The central motif of blood pressure elevation in obesity is increased sodium and water retention due to renin-angiotensin system activation and increased sympathetic activity. Recent analysis of data from real practice points to efficiency and safety and metabolic neutrality of the fixed combination Perindopril/Indapamide in subjects with AH and obesity, type 2 diabetes mellitus or metabolic syndrome.
Background: In most of Taiwan's medical institutions, congestion is a serious problem for emergency departments. Due to a lack of hospital beds, patients spend more time in emergency retention zones, which make it difficult to detect cardiac arrest. Objective: We seek to develop a Drug Early Warning Scoring Model (DEWSM), including drug injections and vital signs as these research important features. We use it to predict cardiac arrest in emergency departments via drug classification and medical experts' suggestion. Methods: We propose this new model for detecting cardiac arrest via drug classification and by using a sliding window, and apply learning-based algorithms to time-series data for a DEWSM. To evaluate the proposed model, we use the area under the receiver operating characteristic curve (AUROC). Results: We identify the two important drug predictors: bits (intravenous therapy), and replenishers and regulators of water and electrolytes (fluid and electrolyte supplement). Weverify feature selection, in which accounting for drugs to improve the accuracy and demonstrate that thus accounting for the drugs significantly affects prediction. Also, we show that CPR events can be predicted four hours before the event. Conclusion: Our study used a sliding window to account for dynamic time-series data consisting of the patient's vital signs and drug injections. The experimental results of adding the drug injections were better than only vital signs. In addition, we using LSTM method as the main processing time series data, it was the bases for comparison of this research.
BACKGROUND: Meropenem dosing for septic critically patients is difficult due to pathophysiological changes associated with sepsis as well as supportive symptomatic therapies. A prospective single-center study assessed whether fluid retention alters meropenem pharmacokinetics and the achievement of the pharmacokinetic/pharmacodynamic (PK/PD) targets for efficacy. METHODS: Twenty-five septic ICU patients (19 m, 6f) aged 32-86 years with the mean APACHE II score of 20.2 (range 11-33), suffering mainly from perioperative intra-abdominal or respiratory infections and septic shock (n = 18), were investigated over three days after the start of extended 3-h i.v. infusions of meropenem q8h. Urinary creatinine clearance (CLcr) and cumulative fluid balance (CFB) were measured daily. Plasma meropenem was measured, and Bayesian estimates of PK parameters were calculated. RESULTS: Eleven patients (9 with peritonitis) were classified as fluid overload (FO) based on a positive day 1 CFB of more than 10% body weight. Compared to NoFO patients (n = 14, 11 with pneumonia), the FO patients had a lower meropenem clearance (CLme 8.5 ± 3.2 vs 11.5 ± 3.5 L/h), higher volume of distribution (V1 14.9 ± 3.5 vs 13.5 ± 4.1 L) and longer half-life (t1/2 1.4 ± 0.63 vs 0.92 ± 0.54 h) (p < 0.05). Over three days, the CFB of the FO patients decreased (11.7 ± 3.3 vs 6.7 ± 4.3 L, p < 0.05) and the PK parameters reached the values comparable with NoFO patients (CLme 12.4 ± 3.8 vs 11.5 ± 2.0 L/h, V1 13.7 ± 2.0 vs 14.0 ± 5.1 L, t1/2 0.81 ± 0.23 vs 0.87 ± 0.40 h). The CLcr and Cockroft-Gault CLcr were stable in time and comparable. The correlation with CLme was weak to moderate (CLcr, day 3 CGCLcr) or absent (day 1 and 2 CGCLcr). Dosing with 2 g meropenem q8h ensured adequate concentrations to treat infections with sensitive pathogens (MIC 2 mg/L). The proportion of pre-dose concentrations exceeding the MIC 8 mg/L and the fraction time with a target-exceeding concentration were higher in the FO group (day 1-3 f Cmin > MIC: 67 vs 27%, p < 0.001; day 1%f T > MIC: 79 ± 17 vs 58 ± 17, p < 0.05). CONCLUSIONS: These findings emphasize the importance of TDM and a cautious approach to augmented maintenance dosing of meropenem to patients with FO infected with less susceptible pathogens, if guided by population covariate relationships between CLme and creatinine clearance.
- MeSH
- antibakteriální látky metabolismus farmakokinetika MeSH
- APACHE MeSH
- Bayesova věta MeSH
- dospělí MeSH
- farmakokinetika * MeSH
- jednotky intenzivní péče organizace a řízení statistika a číselné údaje MeSH
- kritický stav terapie MeSH
- lidé středního věku MeSH
- lidé MeSH
- meropenem metabolismus farmakokinetika MeSH
- prospektivní studie MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- sepse farmakoterapie patofyziologie MeSH
- vodní a elektrolytová rovnováha účinky léků MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Česká republika MeSH
BACKGROUND: Apicomplexa is a diverse phylum comprising unicellular endobiotic animal parasites and contains some of the most well-studied microbial eukaryotes including the devastating human pathogens Plasmodium falciparum and Cryptosporidium hominis. In contrast, data on the invertebrate-infecting gregarines remains sparse and their evolutionary relationship to other apicomplexans remains obscure. Most apicomplexans retain a highly modified plastid, while their mitochondria remain metabolically conserved. Cryptosporidium spp. inhabit an anaerobic host-gut environment and represent the known exception, having completely lost their plastid while retaining an extremely reduced mitochondrion that has lost its genome. Recent advances in single-cell sequencing have enabled the first broad genome-scale explorations of gregarines, providing evidence of differential plastid retention throughout the group. However, little is known about the retention and metabolic capacity of gregarine mitochondria. RESULTS: Here, we sequenced transcriptomes from five species of gregarines isolated from cockroaches. We combined these data with those from other apicomplexans, performed detailed phylogenomic analyses, and characterized their mitochondrial metabolism. Our results support the placement of Cryptosporidium as the earliest diverging lineage of apicomplexans, which impacts our interpretation of evolutionary events within the phylum. By mapping in silico predictions of core mitochondrial pathways onto our phylogeny, we identified convergently reduced mitochondria. These data show that the electron transport chain has been independently lost three times across the phylum, twice within gregarines. CONCLUSIONS: Apicomplexan lineages show variable functional restructuring of mitochondrial metabolism that appears to have been driven by adaptations to parasitism and anaerobiosis. Our findings indicate that apicomplexans are rife with convergent adaptations, with shared features including morphology, energy metabolism, and intracellularity.
Glycosphingolipids (GSL) represent a highly heterogeneous class of lipids with many cellular functions, implicated in a wide spectrum of human diseases. Their isolation, detection, and comprehensive structural analysis is a challenging task due to the structural diversity of GSL molecules. In this work, GSL subclasses are isolated from human plasma using an optimized monophasic ethanol-water solvent system capable to recover a broad range of GSL species. Obtained deproteinized plasma is subsequently purified and concentrated by C18-based solid-phase extraction (SPE). The hydrophilic interaction liquid chromatography coupled to electrospray ionization linear ion trap tandem mass spectrometry (HILIC-ESI-LIT-MS/MS) is used for GSL analysis in the human plasma extract. Our results provide an in-depth profiling and structural characterization of glycosphingolipid and some phospholipid subclasses identified in the human plasma based on their retention times and the interpretation of tandem mass spectra. The structural composition of particular lipid species is readily characterized based on the detailed interpretation of mass spectrometry (MS) and tandem mass spectrometry (MS/MS) spectra and further confirmed by specific fragmentation behavior following predictable patterns, which yields to the unambiguous identification of 154 GSL species within 7 lipid subclasses and 77 phospholipids representing the highest number of GSL species ever reported in the human plasma. The developed HILIC-ESI-MS/MS method can be used for further clinical and biological research of GSL in the human blood or other biological samples.
- Publikační typ
- časopisecké články MeSH
Detection of peptides lies at the core of bottom-up proteomics analyses. We examined a Bayesian approach to peptide detection, integrating match-based models (fragments, retention time, isotopic distribution, and precursor mass) and peptide prior probability models under a unified probabilistic framework. To assess the relevance of these models and their various combinations, we employed a complete- and a tail-complete search of a low-precursor-mass synthetic peptide library based on oncogenic KRAS peptides. The fragment match was by far the most informative match-based model, while the retention time match was the only remaining such model with an appreciable impact--increasing correct detections by around 8 %. A peptide prior probability model built from a reference proteome greatly improved the detection over a uniform prior, essentially transforming de novo sequencing into a reference-guided search. The knowledge of a correct sequence tag in advance to peptide-spectrum matching had only a moderate impact on peptide detection unless the tag was long and of high certainty. The approach also derived more precise error rates on the analyzed combinatorial peptide library than those estimated using PeptideProphet and Percolator, showing its potential applicability for the detection of homologous peptides. Although the approach requires further computational developments for routine data analysis, it illustrates the value of peptide prior probabilities and presents a Bayesian approach for their incorporation into peptide detection.
Závěrečná zpráva o řešení grantu Agentury pro zdravotnický výzkum MZ ČR
Nestr.
Vývoj diagnostických a terapeutických prostředků pro nádorová onemocnění je prioritou současného farmaceutického výzkumu. Hlavním cílem projektu je vyvinutí koncepčně nových dvoufázových nanoradiodiagnostik pro neinvazívní zobrazování pevných nádorů na principu EPR efektu pro zlepšení péče o onkologické pacienty a personalizaci péče. Dále ověříme výhodnost systému pro předpověď efektivity antiangiogenní léčby bevacizumabem na in vivo myším nádorovém modelu. Systém umožní kombinovat klinicky zavedené radionuklidy s relativně krátkým poločasem rozpadu (18-F, 68-Ga a 99m-Tc), které jen málo radiačně zatěžují pacienta, s EPR cílícím efektem, který je nejefektivnější po delší době, která není přímo kompatibilní s poločasem rozpadu těchto radionuklidů.; Development of diagnostic and therapeutic tools for cancer applications represents the top priority of the contemporary pharmaceutical research. The principial aim of the project is the deveĺopment of conceptually new two-staged nanoradiodiagnostics for the noninvasive Enhanced Permeability and Retention (EPR) effect-based imaging of solid tumors to improve care about oncological patients and enable to personalize therapy of solid tumors. We will also prove on an in vivo murine cancer model whether this system has predictive value for further treatment efficacy with antiangiogenic therapy with bevacizumab. The system will allow to combine relatively short half-life radionuclides 18-F, 68-Ga and 99m-Tc (well established in diagnostics and with low whole-body radiation burden for the patient) with the EPR effect, which works best after longer time not directly compatible with half-life of these radionuclides.
- MeSH
- biokompatibilní materiály MeSH
- inhibitory angiogeneze MeSH
- lidé MeSH
- modely nemocí na zvířatech MeSH
- myši MeSH
- nádory diagnostické zobrazování MeSH
- nanočástice MeSH
- polymery MeSH
- radiofarmaka MeSH
- radiografie metody MeSH
- výsledek terapie MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- myši MeSH
- zvířata MeSH
- Konspekt
- Patologie. Klinická medicína
- NLK Obory
- onkologie
- farmacie a farmakologie
- radiologie, nukleární medicína a zobrazovací metody
- NLK Publikační typ
- závěrečné zprávy o řešení grantu AZV MZ ČR
A device with four parallel channels was designed and manufactured by 3D printing in titanium. A simple experimental setup allowed splitting of the mobile phase in four parallel streams, such that a single sample could be analysed four times simultaneously. The four capillary channels were filled with a monolithic stationary phase, prepared using a zwitterionic functional monomer in combination with various dimethacrylate cross-linkers. The resulting stationary phases were applicable in both reversed-phase and hydrophilic-interaction retention mechanisms. The mobile-phase composition was optimized by means of a window diagram so as to obtain the highest possible resolution of dopamine precursors and metabolites on all columns. Miniaturized electrochemical detectors with carbon fibres as working electrodes and silver micro-wires as reference electrodes were integrated in the device at the end of each column. Experimental separations were successfully compared with those predicted by a three-parameter retention model. Finally, dopamine was determined in human urine to further confirm applicability of the developed device.
