31 results on '"Váradi C"'
Search Results
2. AB0023 Combination of Igg N-Glycomics and Corresponding Transcriptomics Data to Identify Anti-Tnf-Alpha Treatment Responders in Rheumatoid Arthritis and Inflammatory Bowel Disease
- Author
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Váradi, C., primary, Guttman, A., additional, Hollό, Z., additional, Poliska, S., additional, Nagy, L., additional, Szekanecz, Z., additional, Váncsa, A., additional, and Palatka, K., additional
- Published
- 2015
- Full Text
- View/download PDF
3. F-038REAL-TIME, IN-VIVO TISSUE IDENTIFICATION DURING THORACIC SURGERY
- Author
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Enyedi, Attila, primary, Takacs, I., additional, Váradi, C., additional, Veres, L., additional, Szabo, K.G., additional, Végh, T., additional, Balog, J., additional, and Takáts, Z., additional
- Published
- 2013
- Full Text
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4. The Impact of Protein Glycosylation on the Identification of Patients with Pediatric Appendicitis.
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Dojcsák D, Farkas F, Farkas T, Papp J, Garami A, Viskolcz B, and Váradi C
- Subjects
- Humans, Glycosylation, Child, Male, Female, Adolescent, Polysaccharides metabolism, Polysaccharides blood, Biomarkers blood, Child, Preschool, Appendicitis diagnosis, Appendicitis blood, Appendicitis metabolism
- Abstract
The identification of pediatric appendicitis is challenging due to the lack of specific markers thereby several factors are included in the diagnostic process such as abdominal pain, ultrasonography and altered laboratory parameters (C reactive protein, absolute neutrophil cell number and white blood cell number). The glycosylation pattern of serum N-glycome was analyzed in this study of 38 controls and 40 patients with pediatric appendicitis. The glycans were released by enzymatic deglycosylation followed by fluorescent labeling and solid-phase extraction. The prepared samples were analyzed by hydrophilic interaction liquid chromatography with fluorescence and mass-spectrometric detection. The generated data were analyzed by multiple statistical tests involving the most important laboratory parameters as well. Significant differences associated with the examined patient groups were revealed suggesting the potential use of glycosylation analysis supporting the detection of pediatric appendicitis.
- Published
- 2024
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- View/download PDF
5. Get reliable laboratory findings - how to recognize the deceptive effects of angiotensin-converting enzyme inhibitor therapy in the laboratory diagnostics of sarcoidosis?
- Author
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Szabó AÁ, Enyedi EE, Altorjay IT, Hajnal P, Pintér TB, Mányiné IS, Váradi C, Bányai E, Tóth A, Papp Z, and Fagyas M
- Subjects
- Humans, Male, Female, Middle Aged, Retrospective Studies, Adult, Biomarkers blood, Angiotensin-Converting Enzyme Inhibitors therapeutic use, Sarcoidosis drug therapy, Sarcoidosis diagnosis, Sarcoidosis blood, Peptidyl-Dipeptidase A blood
- Abstract
Objectives: Serum angiotensin-converting enzyme (ACE) is the only biomarker routinely used in the laboratory diagnostics of sarcoidosis, and ACE inhibitor (ACEi) drugs are among the most prescribed drugs worldwide. Taking ACEi can mislead medical teams by lowering ACE activity, delaying diagnosis and giving a false impression of disease activity of sarcoidosis. We aimed to develop a simple method to detect the presence of ACEi drugs in samples, to investigate the ACEi medication-caused interference and consequences in a retrospective study., Methods: ACE activity and the level of ACE inhibition were determined for 1823 patients with suspected sarcoidosis. These values were compared with the therapeutic information at the first and follow-up visits., Results: A total of 302 patients had biochemical evidence of an ACEi drug effect during diagnostic ACE activity testing. In their case, ACE activity was significantly lower (median(IQR): 4.41 U/L(2.93-6.72)) than in patients not taking ACEi (11.32 U/L(8.79-13.92), p<0.01). In 62 sarcoidosis patients, the ACEi reduced ACE activity to the reference range or below. Only in 40 % of the cases was the medication list recorded in the outpatient chart and only in 3 cases was low ACE activity associated with ACEi use. 67 % of the repeated ACE activity measurements were also performed during ACEi therapy., Conclusions: Our study revealed that the use of ACEi is common in patients with suspected sarcoidosis. The ACE activity lowering effect of ACEi drugs may escape the attention of medical teams which can lead to diagnostic errors and unnecessary tests. Nevertheless, these pitfalls can be avoided by using a method suggested by our team., (© 2024 the author(s), published by De Gruyter, Berlin/Boston.)
- Published
- 2024
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6. Simplified Synthesis of the Amine-Functionalized Magnesium Ferrite Magnetic Nanoparticles and Their Application in DNA Purification Method.
- Author
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Ilosvai ÁM, Gerzsenyi TB, Sikora E, Harasztosi L, Kristály F, Viskolcz B, Váradi C, Szőri-Dorogházi E, and Vanyorek L
- Subjects
- Physical Phenomena, Ethanolamine, Amines, Magnetite Nanoparticles
- Abstract
For pathogens identification, the PCR test is a widely used method, which requires the isolation of nucleic acids from different samples. This extraction can be based on the principle of magnetic separation. In our work, amine-functionalized magnesium ferrite nanoparticles were synthesized for this application by the coprecipitation of ethanolamine in ethylene glycol from Mg(II) and Fe(II) precursors. The conventional synthesis method involves a reaction time of 12 h (MgFe
2 O4 -H&R MNP); however, in our modified method, the reaction time could be significantly reduced to only 4 min by microwave-assisted synthesis (MgFe2 O4 -MW MNP). A comparison was made between the amine-functionalized MgFe2 O4 samples prepared by two methods in terms of the DNA-binding capacity. The experimental results showed that the two types of amine-functionalized magnesium ferrite magnetic nanoparticles (MNPs) were equally effective in terms of their DNA extraction yield. Moreover, by using a few minutes-long microwave synthesis, we obtained the same quality magnesium ferrite particles as those made through the long and energy-intensive 12-h production method. This advancement has the potential to improve and expedite pathogen identification processes, helping to better prevent the spread of epidemics.- Published
- 2023
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7. Preparation and Optical Study of 1-Formamido-5-Isocyanonaphthalene, the Hydrolysis Product of the Potent Antifungal 1,5-Diisocyanonaphthalene.
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Kopcsik E, Mucsi Z, Kontra B, Vanyorek L, Váradi C, Viskolcz B, and Nagy M
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- Hydrolysis, Water, Cyanides, Antifungal Agents pharmacology, Fluorescent Dyes chemistry
- Abstract
Aromatic isocyanides have gained a lot of attention lately as promising antifungal and anticancer drugs, as well as high-performance fluorescent analytical probes for the detection of toxic metals, such as mercury, even in vivo. Since this topic is relatively new and aromatic isocyanides possess unique photophysical properties, the understanding of structure-behavior relationships and the preparation of novel potentially biologically active derivatives are of paramount importance. Here, we report the photophysical characterization of 1,5-diisocyanonaphthalene (DIN) backed by quantum chemical calculations. It was discovered that DIN undergoes hydrolysis in certain solvents in the presence of oxonium ions. By the careful control of the reaction conditions for the first time, the nonsymmetric product 1-formamido-5-isocyanonaphthalene (ICNF) could be prepared. Contrary to expectations, the monoformamido derivative showed a significant solvatochromic behavior with a ~50 nm range from hexane to water. This behavior was explained by the enhanced H-bond-forming ability of the formamide group. The significance of the hydrolysis reaction is that the isocyano group is converted to formamide in living organisms. Therefore, ICNF could be a potential drug (for example, antifungal) and the reaction can be used as a model for the preparation of other nonsymmetric formamido-isocyanoarenes. In contrast to its relative 1-amino-5-iscyanonaphthalene (ICAN), ICNF is highly fluorescent in water, enabling the development of a fluorescent turnoff probe.
- Published
- 2023
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8. The Alterations of Serum N-glycome in Response to SARS-CoV-2 Vaccination.
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Dojcsák D, Kardos Z, Szabó M, Oláh C, Körömi Z, Viskolcz B, and Váradi C
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- Humans, COVID-19 Vaccines, SARS-CoV-2, Vaccination, RNA, Messenger, COVID-19 prevention & control
- Abstract
The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has caused a global concern since its outbreak in 2019, with one of the main solutions being vaccination. Altered glycosylation has been described in patients after SARS-CoV-2 infection, while the effect of vaccination on serum glycoproteins remained unexplored. In this study, total serum glycosylation was analyzed in patients after SARS-CoV-2 infection and/or mRNA vaccination in order to identify potential glycosylation-based alterations. Enzyme-linked immunosorbent assay was applied to identify post-COVID-19 and post-Vaccinated patients and rule out potential outliers. Serum samples were deglycosylated by PNGase F digestion, and the released glycans were fluorescently derivatized using procainamide labeling. Solid-phase extraction was used to purify the labeled glycans followed by the analysis of hydrophilic-interaction liquid chromatography with fluorescence and mass-spectrometric detection. Alterations of serum N-glycome in response to SARS-CoV-2 infection and mRNA vaccination were revealed by linear discriminant analysis.
- Published
- 2023
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9. A Simplified and Efficient Method for Production of Manganese Ferrite Magnetic Nanoparticles and Their Application in DNA Isolation.
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Gerzsenyi TB, Ilosvai ÁM, Szilágyi G, Szőri M, Váradi C, Viskolcz B, Vanyorek L, and Szőri-Dorogházi E
- Subjects
- Sodium Chloride, Manganese Compounds, Ferric Compounds, DNA, Bacterial, Magnetite Nanoparticles
- Abstract
A simplified, fast, and effective production method has been developed for the synthesis of manganese ferrite (MnFe
2 O4 ) magnetic nanoparticles (MNPs). In addition to the wide applicability of MnFe2 O4 MNPs, this work also reports their application in DNA isolation for the first time. An ultrasonic-cavitation-assisted combustion method was applied in the synthesis of MnFe2 O4 MNPs at different furnace temperatures (573 K, 623 K, 673 K, and 773 K) to optimize the particles' properties. It was shown that MnFe2 O4 nanoparticles synthesized at 573 K consist of a spinel phase only with adequate size and zeta potential distributions and superparamagnetic properties. It was also demonstrated that superparamagnetic manganese ferrite nanoparticles bind DNA in buffer with a high NaCl concentration (2.5 M), and the DNA desorbs from the MNPs by decreasing the NaCl concentration of the elution buffer. This resulted in a DNA yield comparable to that of commercial DNA extraction products. Both the DNA concentration measurements and electrophoresis confirmed that a high amount of isolated bacterial plasmid DNA (pDNA) with adequate purity can be extracted with MnFe2 O4 (573 K) nanoparticles by applying the DNA extraction method proposed in this article.- Published
- 2023
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10. NH 2 -Functionalized Magnetic Nanoparticles for the N -Glycomic Analysis of Patients with Multiple Sclerosis.
- Author
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Dojcsák D, Ilosvai ÁM, Vanyorek L, Gilányi I, Oláh C, Horváth L, and Váradi C
- Subjects
- Glycomics methods, Glycosylation, Humans, Polysaccharides chemistry, Magnetite Nanoparticles, Multiple Sclerosis
- Abstract
Glycosylation is vital for well-functioning glycoproteins and is reportedly altered in chronic inflammatory disorders, including multiple sclerosis (MS). High-throughput quantitative measurement of protein glycosylation is challenging, as glycans lack fluorophore groups and require fluorescent labeling. The attachment of fluorescent tags to each glycan moiety necessitates sample clean-up for reliable quantitation. The use of magnetic particles in glycan sample preparation is reportedly an easy-to-use solution to accomplish large-scale biomarker discovery studies. In this study, NH
2 -funtionalized magnetic nanoparticles were synthetized, characterized and applied for the glycosylation analysis of serum samples from patients diagnosed with multiple sclerosis and corresponding healthy controls. Serum samples were PNGase F digested and labeled by procainamide via reductive amination, followed by magnetic nanoparticle-based purification. The prepared samples were analyzed by hydrophilic interaction liquid chromatography, allowing for the relative quantitation of the individual glycan species. Significant glycosylation alterations were detected between MS patients and healthy controls, especially when analyzing the different gender groups.- Published
- 2022
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11. Sonochemical Combined Synthesis of Nickel Ferrite and Cobalt Ferrite Magnetic Nanoparticles and Their Application in Glycan Analysis.
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Ilosvai AM, Dojcsak D, Váradi C, Nagy M, Kristály F, Fiser B, Viskolcz B, and Vanyorek L
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- Cobalt chemistry, Ferric Compounds chemistry, Humans, Oxides, Spectroscopy, Fourier Transform Infrared, Magnetite Nanoparticles, Nickel chemistry
- Abstract
The combination of the sonochemical activation of Ni(NO
3 )2 and Co(NO3 )2 in the presence of Fe(NO3 )3 and polyethylene glycol and consecutive heat treatment of the formed metal hydroxides offers a cheap and efficient method for the preparation of nickel ferrite and cobalt ferrite magnetic nanoparticles, which can be successfully applied in the selective capture of fluorescently derivatized N-glycans from human serum. XRD measurement revealed that, besides the ferrite phase, nickel and cobalt oxides also form during heat treatment. The amount of simple metal oxides can be well controlled by the temperature of the heat treatment, since increasing temperature yielded higher spinel content. For both nickel and cobalt, the best heat treatment temperature was found to be 673 K, where the samples contained 84.1% nickel ferrite, and in the case of cobalt, almost pure (99.6%) cobalt ferrite could be prepared. FT-IR and zeta potential measurements indicated the presence of surface OH groups, which aided in the dispersion of the particles in water and, in addition, can promote the adsorption of polar compounds. The practical applicability of the magnetic nanopowders was demonstrated in the purification of fluorescently derivatized N-glycans (from human serum). Cobalt ferrite was found to be the most effective. Owing to the easy preparation and the simplicity of the magnetic separation the pure cobalt ferrite, magnetic nanoparticles could be efficient tools for the selective enrichment of serum N-glycans in HPLC measurements.- Published
- 2022
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12. A debreceni mellkassebészet: múlt és jelen.
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Takács I, Enyedi A, Váradi C, Kóder G, Mudriczki G, and Tóth D
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- 2022
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13. Human Tissue Angiotensin Converting Enzyme (ACE) Activity Is Regulated by Genetic Polymorphisms, Posttranslational Modifications, Endogenous Inhibitors and Secretion in the Serum, Lungs and Heart.
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Bánhegyi V, Enyedi A, Fülöp GÁ, Oláh A, Siket IM, Váradi C, Bottyán K, Lódi M, Csongrádi A, Umar AJ, Fagyas M, Czuriga D, Édes I, Pólos M, Merkely B, Csanádi Z, Papp Z, Szabó G, Radovits T, Takács I, and Tóth A
- Subjects
- Aged, Female, Humans, Lung metabolism, Male, Middle Aged, Myocardium metabolism, Peptidyl-Dipeptidase A analysis, Peptidyl-Dipeptidase A blood, Peptidyl-Dipeptidase A genetics, Polymorphism, Genetic, Protein Processing, Post-Translational, Peptidyl-Dipeptidase A metabolism
- Abstract
Objective: Inhibitors of the angiotensin converting enzyme (ACE) are the primarily chosen drugs to treat heart failure and hypertension. Moreover, an imbalance in tissue ACE/ACE2 activity is implicated in COVID-19. In the present study, we tested the relationships between circulating and tissue (lung and heart) ACE levels in men. Methods: Serum, lung ( n = 91) and heart ( n = 72) tissue samples were collected from Caucasian patients undergoing lung surgery or heart transplantation. ACE I/D genotype, ACE concentration and ACE activity were determined from serum and tissue samples. Clinical parameters were also recorded. Results: A protocol for ACE extraction was developed for tissue ACE measurements. Extraction of tissue-localized ACE was optimal in a 0.3% Triton-X-100 containing buffer, resulting in 260 ± 12% higher ACE activity over detergent-free conditions. SDS or higher Triton-X-100 concentrations inhibited the ACE activity. Serum ACE concentration correlated with ACE I/D genotype (II: 166 ± 143 ng/mL, n = 19, ID: 198 ± 113 ng/mL, n = 44 and DD: 258 ± 109 ng/mL, n = 28, p < 0.05) as expected. In contrast, ACE expression levels in the lung tissue were approximately the same irrespective of the ACE I/D genotype (II: 1423 ± 1276 ng/mg, ID: 1040 ± 712 ng/mg and DD: 930 ± 1273 ng/mg, p > 0.05) in the same patients (values are in median ± IQR). Moreover, no correlations were found between circulating and lung tissue ACE concentrations and activities (Spearman's p > 0.05). In contrast, a significant correlation was identified between ACE activities in serum and heart tissues (Spearman's Rho = 0.32, p < 0.01). Finally, ACE activities in lung and the serum were endogenously inhibited to similar degrees (i.e., to 69 ± 1% and 53 ± 2%, respectively). Conclusion: Our data suggest that circulating ACE activity correlates with left ventricular ACE, but not with lung ACE in human. More specifically, ACE activity is tightly coordinated by genotype-dependent expression, endogenous inhibition and secretion mechanisms.
- Published
- 2021
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14. The Analysis of Human Serum N-Glycosylation in Patients with Primary and Metastatic Brain Tumors.
- Author
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Váradi C, Hajdu V, Farkas F, Gilányi I, Oláh C, and Viskolcz B
- Abstract
The identification of patients with different brain tumors is solely built on imaging diagnostics, indicating the need for novel methods to facilitate disease recognition. Glycosylation is a chemical modification of proteins, reportedly altered in several inflammatory and malignant diseases, providing a potential alternative route for disease detection. In this paper, we report the quantitative analysis of serum N-glycosylation of patients diagnosed with primary and metastatic brain tumors. PNGase-F-digested and procainamide-labeled serum glycans were purified by magnetic nanoparticles, followed by quantitative liquid chromatographic analysis. The glycan structures were identified by the combination of single quad mass spectrometric detection and exoglycosidase digestions. Linear discriminant analysis provided a clear separation of different disease groups and healthy controls based on their N-glycome pattern. Altered distribution of biantennary neutral, sialylated but nonfucosylated, and sialylated-fucosylated structures were found to be the most significant changes. Our results demonstrate that serum glycosylation monitoring could improve the detection of malignancy.
- Published
- 2021
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15. Clinical Features of Parkinson's Disease: The Evolution of Critical Symptoms.
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Váradi C
- Abstract
Parkinson's disease (PD) is a multi-attribute neurodegenerative disorder combining motor and nonmotor symptoms without well-defined diagnostic clinical markers. The presence of primary motor features (bradykinesia, rest tremor, rigidity and loss of postural reflexes) are the most characteristic signs of PD that are also utilized to identify patients in current clinical practice. The successful implementation of levodopa treatment revealed that nonmotor features are the main contributors of patient disability in PD, and their occurrence might be earlier than motor symptoms during disease progression. Targeted detection of prodromal PD symptoms can open up new possibilities in the identification of PD patients and provide potential patient populations for developing novel neuroprotective therapies. In this review, the evolution of critical features in PD diagnosis is described with special attention to nonmotor symptoms and their possible detection.
- Published
- 2020
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16. Analysis of cetuximab N-Glycosylation using multiple fractionation methods and capillary electrophoresis mass spectrometry.
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Váradi C, Jakes C, and Bones J
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- Amino Acid Sequence, Binding Sites, Biosensing Techniques, Chemical Fractionation, Chromatography, Reverse-Phase, Electrophoresis, Capillary, Glycoside Hydrolases chemistry, Glycosylation, Mass Spectrometry, Peptide Mapping methods, Protein Binding, Protein Conformation, Cetuximab chemistry, Galactose chemistry, Neuraminic Acids chemistry, Polysaccharides chemistry
- Abstract
Site-specific glycosylation of Cetuximab was characterized in this study using multiple fractionation methods and capillary electrophoresis coupled to mass spectrometry (CE-MS) based glycomics. IdeS digested Cetuximab with subsequent reduction was fractionated using reversed-phase chromatography resulting in 3 fragments; Fd, Lc and Fc/2. Glycan release of the different fragments was performed in
18 O enriched water providing the possible quantification of site occupancy. 2-AA labelled glycan structures were annotated by CE-MS profiling in combination with exoglycosidase sequencing, revealing potential structures with terminal α-galactose and N-glycolyl-neuraminic acid (NGNA) mainly originating from the Fd fragment. Glycosylation analysis was also performed on different charge variants of Cetuximab that were separated using pH gradient cation-exchange chromatography to investigate the impact of glycosylation on the net charge of the protein., Competing Interests: Declaration of Competing Interest The authors declare no conflict of interest., (Copyright © 2019 Elsevier B.V. All rights reserved.)- Published
- 2020
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17. Combined application of angiotensin converting enzyme and chitotriosidase analysis improves the laboratory diagnosis of sarcoidosis.
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Enyedi A, Csongrádi A, Altorjay IT, Beke GL, Váradi C, Enyedi EE, Kiss DR, Bányai E, Kalina E, Kappelmayer J, Tóth A, Papp Z, Takács I, and Fagyas M
- Subjects
- Adult, Female, Humans, Male, Middle Aged, Blood Chemical Analysis, Hexosaminidases blood, Peptidyl-Dipeptidase A blood, Sarcoidosis blood, Sarcoidosis diagnosis
- Abstract
Establishing the diagnosis of sarcoidosis most often requires biopsy and histopathologic evaluation, since there is no single marker with sufficient specificity and sensitivity for the disease. Our aims were to determine and compare the diagnostic accuracies of several potential biomarkers and to develop a combined biomarker analysis tool for the diagnosis of sarcoidosis. 133 healthy individuals and 104 patients with suspected sarcoidosis and diagnostic thoracic surgery were enrolled into this study. Histopathologic results were contrasted to biomarker levels of chitotriosidase (CTO), serum amyloid-A (SAA), soluble interleukin-2 receptor (sIL-2R), lysozyme (LZM) or angiotensin converting enzyme (ACE). Sarcoidosis was confirmed by histopathology in 69 patients. CTO activity, sIL-2R concentration and ACE activity could discriminate between sarcoidosis and control patients, while SAA and LZM concentrations could not. A new combined parameter, which was derived from the multiplication of ACE by CTO activities (double product) showed the best diagnostic accuracy in this clinical study: (AUC = 0.898, sensitivity: 90.5%, specificity: 79.3%, positive and negative predictive values: 90.5% and 79.3%, respectively). Sarcoidosis can be diagnosed with the combined analysis of ACE and CTO activities more accurately than with single serum biomarkers in the absence of invasive biopsy in the majority of cases with pulmonary manifestation of sarcoidosis., (Copyright © 2019 Elsevier B.V. All rights reserved.)
- Published
- 2020
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18. Purification of Fluorescently Derivatized N-Glycans by Magnetic Iron Nanoparticles.
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Váradi C, Sikora E, Vanyorek L, and Viskolcz B
- Abstract
A novel glycoanalytical approach was developed in this study for the purification of fluorescently derivatized N-glycans. Polyethylene glycol (PEG) modified iron-nanoparticles were synthetized by the combination of sonochemical treatment and combustion method. The prepared nanomaterials were applied for a systematic clean-up optimization to maximize purification efficiency of 2-AA labelled glycans. PEG 1000 modified iron-oxalate was found to be the most effective for the selective enrichment of serum N-glycans providing high reproducibility. Different acetonitrile percentages for binding and washing steps were also tested to ensure the same relative peak areas compared to the unpurified sample. The generated novel clean-up strategy provides a potential route to use in-house synthetized magnetic nanoparticles for glycan sample preparation.
- Published
- 2019
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19. Serum N-Glycosylation in Parkinson's Disease: A Novel Approach for Potential Alterations.
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Váradi C, Nehéz K, Hornyák O, Viskolcz B, and Bones J
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- Algorithms, Electrophoresis, Capillary, Glycosylation, Humans, Tandem Mass Spectrometry, Parkinson Disease metabolism, Support Vector Machine
- Abstract
In this study, we present the application of a novel capillary electrophoresis (CE) method in combination with label-free quantitation and support vector machine-based feature selection (support vector machine-estimated recursive feature elimination or SVM-RFE) to identify potential glycan alterations in Parkinson's disease. Specific focus was placed on the use of neutral coated capillaries, by a dynamic capillary coating strategy, to ensure stable and repeatable separations without the need of non-mass spectrometry (MS) friendly additives within the separation electrolyte. The developed online dynamic coating strategy was applied to identify serum N-glycosylation by CE-MS/MS in combination with exoglycosidase sequencing. The annotated structures were quantified in 15 controls and 15 Parkinson's disease patients by label-free quantitation. Lower sialylation and increased fucosylation were found in Parkinson's disease patients on tri-antennary glycans with 2 and 3 terminal sialic acids. The set of potential glycan alterations was narrowed by a recursive feature elimination algorithm resulting in the efficient classification of male patients.
- Published
- 2019
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20. Multi-site N-Glycan mapping study 2: UHPLC.
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Szekrényes Á, Park SS, Cosgrave E, Jones A, Haxo T, Kimzey M, Pourkaveh S, Szabó Z, Sosic Z, Feng P, Sejwal P, Dent K, Michels D, Freckleton G, Qian J, Lancaster C, Duffy T, Schwartz M, Luo JK, van Dyck J, Leung PK, Olajos M, Kowle R, Gao K, Wang W, Wegstein J, Tep S, Domokos A, Váradi C, and Guttman A
- Subjects
- Benzamides chemistry, Binding Sites, Electrophoresis, Capillary methods, Glycosylation, Humans, Limit of Detection, Reproducibility of Results, Spectrometry, Fluorescence methods, Chromatography, High Pressure Liquid methods, Fluorescent Dyes chemistry, Polysaccharides analysis
- Abstract
In the first part of this publication, the results from an international study evaluating the precision (i.e., repeatability and reproducibility) of N-glycosylation analysis using capillary electrophoresis of APTS-labeled N-glycans were presented. The corresponding results from ultra-high performance liquid chromatography (UHPLC) with fluorescence detection are presented here from 12 participating sites. All participants used the same lot of samples, reagents, and columns to perform the assays. Elution time, peak area and peak area percent values were determined for all peaks ≥0.1% peak area, and statistical analysis was performed following ISO 5725-2 guideline principles. The results demonstrated adequate reproducibility, within any given site as well across all sites, indicating that standard UHPLC-based N-glycan analysis platforms are appropriate for general use., (© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)
- Published
- 2018
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21. Quantitative glycomics using liquid phase separations coupled to mass spectrometry.
- Author
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Smith J, Mittermayr S, Váradi C, and Bones J
- Subjects
- Glycosylation, Polysaccharides, Glycomics, Glycoproteins chemistry, Mass Spectrometry
- Abstract
Post-translational modification of proteins by the attachment of glycans is governed by a variety of highly specific enzymes and is associated with fundamental impacts on the parent protein's physical, chemical and biological properties. The inherent connection between cellular physiology and specific glycosylation patterns has been shown to offer potential for diagnostic and prognostic monitoring of altered glycosylation in the disease state. Conversely, glycoprotein based biopharmaceuticals have emerged as dominant therapeutic strategies in the treatment of intricate diseases. Glycosylation present on these biopharmaceuticals represents a major critical quality attribute with impacts on both pharmacokinetics and pharmacodynamics. The structural variety of glycans, based upon their non-template driven assembly, poses a significant analytical challenge for both qualitative and quantitative analysis. Labile monosaccharide constituents, isomeric species and often low sample availability from biological sources necessitates meticulous sample handling, ultra-high-resolution analytical separation and sensitive detection techniques, respectively. In this article a critical review of analytical quantitation approaches using liquid phase separations coupled to mass spectrometry for released glycans of biopharmaceutical and biomedical significance is presented. Considerations associated with sample derivatisation strategies, ionisation, relative quantitation through isotopic as well as isobaric labelling, metabolic/enzymatic incorporation and targeted analysis are all thoroughly discussed.
- Published
- 2017
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22. Stable Isotope Quantitative N-Glycan Analysis by Liquid Separation Techniques and Mass Spectrometry.
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Mittermayr S, Albrecht S, Váradi C, Millán-Martín S, and Bones J
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- Aniline Compounds chemistry, Animals, Humans, Isotope Labeling methods, Isotopes chemistry, Polysaccharides chemistry, ortho-Aminobenzoates chemistry, Chromatography, Liquid methods, Electrophoresis, Capillary methods, Mass Spectrometry methods, Polysaccharides analysis, Polysaccharides isolation & purification
- Abstract
Liquid phase separation analysis and subsequent quantitation remains a challenging task for protein-derived oligosaccharides due to their inherent structural complexity and diversity. Incomplete resolution or co-detection of multiple glycan species complicates peak area-based quantitation and associated statistical analysis when optical detection methods are used. The approach outlined herein describes the utilization of stable isotope variants of commonly used fluorescent tags that allow for mass-based glycan identification and relative quantitation following separation by liquid chromatography (LC) or capillary electrophoresis (CE). Comparability assessment of glycoprotein-derived oligosaccharides is performed by derivatization with commercially available isotope variants of 2-aminobenzoic acid or aniline and analysis by LC- and CE-mass spectrometry. Quantitative information is attained from the extracted ion chromatogram/electropherogram ratios generated from the light and heavy isotope clusters.
- Published
- 2017
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23. Quantitative twoplex glycan analysis using 12 C 6 and 13 C 6 stable isotope 2-aminobenzoic acid labelling and capillary electrophoresis mass spectrometry.
- Author
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Váradi C, Mittermayr S, Millán-Martín S, and Bones J
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- Antibodies, Monoclonal chemistry, Antibodies, Monoclonal isolation & purification, Carbohydrate Sequence, Carbon Isotopes, Glycoproteins chemistry, Glycoproteins isolation & purification, Hydrogen-Ion Concentration, Oligosaccharides chemistry, Electrophoresis, Capillary methods, Isotope Labeling methods, Mass Spectrometry methods, Oligosaccharides isolation & purification, ortho-Aminobenzoates chemistry
- Abstract
Capillary electrophoresis (CE) offers excellent efficiency and orthogonality to liquid chromatographic (LC) separations for oligosaccharide structural analysis. Combination of CE with high resolution mass spectrometry (MS) for glycan analysis remains a challenging task due to the MS incompatibility of background electrolyte buffers and additives commonly used in offline CE separations. Here, a novel method is presented for the analysis of 2-aminobenzoic acid (2-AA) labelled glycans by capillary electrophoresis coupled to mass spectrometry (CE-MS). To ensure maximum resolution and excellent precision without the requirement for excessive analysis times, CE separation conditions including the concentration and pH of the background electrolyte, the effect of applied pressure on the capillary inlet and the capillary length were evaluated. Using readily available
12/13 C6 stable isotopologues of 2-AA, the developed method can be applied for quantitative glycan profiling in a twoplex manner based on the generation of extracted ion electropherograms (EIE) for12 C6 'light' and13 C6 'heavy' 2-AA labelled glycan isotope clusters. The twoplex quantitative CE-MS glycan analysis platform is ideally suited for comparability assessment of biopharmaceuticals, such as monoclonal antibodies, for differential glycomic analysis of clinical material for potential biomarker discovery or for quantitative microheterogeneity analysis of different glycosylation sites within a glycoprotein. Additionally, due to the low injection volume requirements of CE, subsequent LC-MS analysis of the same sample can be performed facilitating the use of orthogonal separation techniques for structural elucidation or verification of quantitative performance.- Published
- 2016
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24. Multi-Site N-glycan mapping study 1: Capillary electrophoresis - laser induced fluorescence.
- Author
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Szekrényes Á, Park SS, Santos M, Lew C, Jones A, Haxo T, Kimzey M, Pourkaveh S, Szabó Z, Sosic Z, Feng P, Váradi C, de l'Escaille F, Falmagne JB, Sejwal P, Niedringhaus T, Michels D, Freckleton G, Hamm M, Manuilov A, Schwartz M, Luo JK, van Dyck J, Leung PK, Olajos M, Gu Y, Gao K, Wang W, Wegstein J, Tep S, and Guttman A
- Subjects
- Chromatography, High Pressure Liquid methods, Electrophoresis, Capillary, Humans, Polysaccharides analysis, Fluorescence, Lasers, Polysaccharides chemistry
- Abstract
An international team that included 20 independent laboratories from biopharmaceutical companies, universities, analytical contract laboratories and national authorities in the United States, Europe and Asia was formed to evaluate the reproducibility of sample preparation and analysis of N-glycans using capillary electrophoresis of 8-aminopyrene-1,3,6-trisulfonic acid (APTS)-labeled glycans with laser induced fluorescence (CE-LIF) detection (16 sites) and ultra high-performance liquid chromatography (UHPLC, 12 sites; results to be reported in a subsequent publication). All participants used the same lot of chemicals, samples, reagents, and columns/capillaries to run their assays. Migration time, peak area and peak area percent values were determined for all peaks with >0.1% peak area. Our results demonstrated low variability and high reproducibility, both, within any given site as well across all sites, which indicates that a standard N-glycan analysis platform appropriate for general use (clone selection, process development, lot release, etc.) within the industry can be established.
- Published
- 2016
- Full Text
- View/download PDF
25. Comparative glycoprofiling of HIV gp120 immunogens by capillary electrophoresis and MALDI mass spectrometry.
- Author
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Guttman M, Váradi C, Lee KK, and Guttman A
- Subjects
- Glycosylation, HIV Envelope Protein gp120 immunology, Carbohydrates analysis, Electrophoresis, Capillary methods, HIV Envelope Protein gp120 chemistry, Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization methods, Vaccines, Synthetic chemistry
- Abstract
The human immunodeficiency virus (HIV) envelope glycoprotein (Env) is the primary antigenic feature on the surface of the virus and is of key importance in HIV vaccinology. Vaccine trials with the gp120 subunit of Env are ongoing, with the recent RV144 trial showing moderate efficacy. gp120 is densely covered with N-linked glycans that are thought to help evade the host's humoral immune response. To assess how the global glycosylation patterns vary between gp120 constructs, the glycan profiles of several gp120s were examined by CE with LIF detection and MALDI-MS. The glycosylation profiles were found to be similar for chronic versus transmitter/founder isolates and only varied moderately between gp120s from different clades. This study revealed that the addition of specific tags, such as the herpes simplex virus glycoprotein D tag used in the RV144 trial, had significant effects on the overall glycosylation patterns. Such effects are likely to influence the immunogenicity of various Env immunogens and should be considered for future vaccine strategies, emphasizing the importance of the glycosylation analysis approach described in this paper., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)
- Published
- 2015
- Full Text
- View/download PDF
26. Combination of IgG N-glycomics and corresponding transcriptomics data to identify anti-TNF-α treatment responders in inflammatory diseases.
- Author
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Váradi C, Holló Z, Póliska S, Nagy L, Szekanecz Z, Váncsa A, Palatka K, and Guttman A
- Subjects
- Adult, Arthritis, Rheumatoid immunology, Crohn Disease immunology, Female, Fluorescent Dyes chemistry, Glycomics, Humans, Male, Treatment Outcome, Arthritis, Rheumatoid drug therapy, Crohn Disease drug therapy, Immunoglobulin G chemistry, Transcriptome, Tumor Necrosis Factor-alpha antagonists & inhibitors
- Abstract
Prediction of responsiveness in biological therapies is an important and challenging issue in different diseases. Analyzing glycosylation pattern changes of key serum glycoproteins is one of the possible avenues to follow disease remission. The aim of this study was to investigate the changes of serum IgG glycoforms in Crohn's disease (CD) and rheumatoid arthritis patients in response to antitumor necrosis factor alpha (anti-TNF-α) treatment. IgG was isolated from patient serum samples using Protein A affinity pull-down, followed by the release of N-glycans with peptide-N-glycosidase F. The released glycans were fluorescently tagged with 8-aminopyrene-1,3,6-trisulfonate and analyzed by CGE with laser-induced fluorescent detection. Significant alterations were detected between responders and nonresponders in both disease groups. In CD patients, disease-specific alteration was found in response to anti-TNF-α therapy, which was also confirmed by transcriptomics data analysis of the corresponding glycosyltransferases and glycosidases., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)
- Published
- 2015
- Full Text
- View/download PDF
27. Rapid magnetic bead based sample preparation for automated and high throughput N-glycan analysis of therapeutic antibodies.
- Author
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Váradi C, Lew C, and Guttman A
- Subjects
- Electrophoresis, Capillary, Antibodies chemistry, Automation, High-Throughput Screening Assays, Magnetics, Polysaccharides analysis
- Abstract
Full automation to enable high throughput N-glycosylation profiling and sequencing with good reproducibility is vital to fulfill the contemporary needs of the biopharmaceutical industry and requirements of national regulatory agencies. The most prevalently used glycoanalytical methods of capillary electrophoresis and hydrophilic interaction liquid chromatography, while very efficient, both necessitate extensive sample preparation and cleanup, including glycoprotein capture, N-glycan release, fluorescent derivatization, purification, and preconcentration steps during the process. Currently used protocols to fulfill these tasks require multiple centrifugation and vacuum-centrifugation steps, making liquid handling robot mediated automated sample preparation difficult and expensive. In this paper we report on a rapid magnetic bead based sample preparation approach that enables full automation including all the process phases just in a couple of hours without requiring any centrifugation and/or vacuum centrifugation steps. This novel protocol has been compared to conventional glycan sample preparation strategies using standard glycoproteins (IgG, fetuin, and RNase B) and featured rapid processing time, high release and labeling efficiency, good reproducibility, and the potential of easy automation.
- Published
- 2014
- Full Text
- View/download PDF
28. Analysis of haptoglobin N-glycome alterations in inflammatory and malignant lung diseases by capillary electrophoresis.
- Author
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Váradi C, Mittermayr S, Szekrényes Á, Kádas J, Takacs L, Kurucz I, and Guttman A
- Subjects
- Biomarkers blood, Biomarkers chemistry, Glycoside Hydrolases blood, Glycoside Hydrolases metabolism, Glycosylation, Haptoglobins chemistry, Haptoglobins metabolism, Humans, Male, Middle Aged, Polysaccharides metabolism, Statistics, Nonparametric, Electrophoresis, Capillary methods, Haptoglobins analysis, Lung Diseases blood, Polysaccharides blood, Polysaccharides chemistry
- Abstract
A CE-based method was introduced to compare the N-glycosylation profile of haptoglobin in normal and pathologic conditions. To assess the biomarker potential of glycosylation changes in various lung diseases, haptoglobin was isolated from plasma samples of healthy, pneumonia, chronic obstructive pulmonary disease, and lung cancer patients by means of two haptoglobin-specific monoclonal antibodies. Haptoglobin N-glycans were then enzymatically released, fluorescently labeled, and profiled by CE. Disease-associated changes of core and antennary fucosylation were identified by targeted exoglycosidase digestions and their levels were compared in the different patient groups. Terms such as core- and arm-fucosylation degree, as well as branching degree, were introduced for easier characterization of the changes and statistical analysis was used to examine which structures were responsible for the observed differences. Increased level of α1-6 fucosylated tri-antennary glycans was found in all disease groups compared to the control. Elevated amounts of core- and arm-fucosylation on tetra-antennary glycans were detected in the lung cancer group compared to the chronic obstructive pulmonary disease group. A larger scale study is necessary to confirm and validate these preliminary findings in the glycosylation changes of haptoglobin, so could then be used as biomarkers in the diagnosis of malignant and inflammatory lung diseases., (© 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)
- Published
- 2013
- Full Text
- View/download PDF
29. [Our experience with patients operated after neoadjuvant therapy].
- Author
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Juhász M, Egri G, Váradi C, Mészáros Z, and Keszler P
- Subjects
- Antineoplastic Combined Chemotherapy Protocols therapeutic use, Carcinoma, Non-Small-Cell Lung drug therapy, Carcinoma, Non-Small-Cell Lung mortality, Carcinoma, Non-Small-Cell Lung pathology, Carcinoma, Non-Small-Cell Lung radiotherapy, Carcinoma, Non-Small-Cell Lung surgery, Chemotherapy, Adjuvant, Female, Humans, Hungary, Lung Neoplasms drug therapy, Lung Neoplasms mortality, Lung Neoplasms pathology, Lung Neoplasms radiotherapy, Lung Neoplasms surgery, Lymphatic Metastasis, Male, Middle Aged, Neoplasm Staging, Radiotherapy, Adjuvant, Remission Induction, Retrospective Studies, Carcinoma, Non-Small-Cell Lung therapy, Lung Neoplasms therapy, Neoadjuvant Therapy, Pneumonectomy adverse effects, Pneumonectomy methods, Pneumonectomy mortality
- Abstract
The authors performed thoracotomies on 47 patients because of NSCLC between 1 January 2000 and 31 December 2003. All patients had neoadjuvant therapy which was indicated by IIIA stage NSCLC with N2 nodal status. After the neoadjuvant therapy almost all tumors (92.7%) became resectable. The combinations of therapy types, the operations type and the surgical complications are analysed. Long term outcome proves, that multimodal therapy of NSCLC (in IIIA stage) is an effective treatment method.
- Published
- 2004
30. [Simultaneous occurrence of small intestine mesenchymoma and rectal carcinoma].
- Author
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Tasi R, Váradi C, Szabó MM, and Réfi M
- Subjects
- Adenocarcinoma pathology, Adenocarcinoma surgery, Female, Humans, Ileal Neoplasms pathology, Ileal Neoplasms surgery, Intestinal Neoplasms pathology, Intestinal Neoplasms surgery, Jejunal Neoplasms diagnosis, Jejunal Neoplasms pathology, Jejunal Neoplasms surgery, Mesenchymoma pathology, Mesenchymoma surgery, Middle Aged, Neoplasms, Multiple Primary pathology, Neoplasms, Multiple Primary surgery, Rectal Neoplasms pathology, Rectal Neoplasms surgery, Sigmoid Neoplasms diagnosis, Sigmoid Neoplasms pathology, Sigmoid Neoplasms surgery, Adenocarcinoma diagnosis, Intestinal Neoplasms diagnosis, Mesenchymoma diagnosis, Neoplasms, Multiple Primary diagnosis, Rectal Neoplasms diagnosis
- Abstract
The authors report the presentation of a rare small bowel mesenchymoma at the jejuno-ileal transition found during the operation of an adenocarcinoma of the recto-sigmoid junction. They discuss the pathology and clinic of the benign mesenchymal tumors of the small intestine.
- Published
- 1997
31. [Therapy of obesity].
- Author
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Dóczy P, Váradi C, Bartel G, Róna L, and Sass I
- Subjects
- Appetite Depressants therapeutic use, Diet, Reducing, Hormones therapeutic use, Humans, Obesity therapy
- Published
- 1965
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