99 results on '"Gasparics, A."'
Search Results
2. The effect of an additional pre-extubational loading dose of caffeine citrate on mechanically ventilated preterm infants (NEOKOFF trial): Study protocol for a multicenter randomized clinical trial.
- Author
-
Kinga Kovács, Rita Nagy, Lilla Andréka, Brigitta Teutsch, Miklós Szabó, Péter Varga, Péter Hegyi, Péter Hársfalvi, Nándor Ács, Ágnes Harmath, Csaba Nádor, and Ákos Gasparics
- Subjects
Medicine ,Science - Abstract
BackgroundMinimizing the duration of mechanical ventilation is one of the most important therapeutic goals during the care of preterm infants at neonatal intensive care units (NICUs). The rate of extubation failure among preterm infants is between 16% and 40% worldwide. Numerous studies have been conducted on the assessment of extubation suitability, the optimal choice of respiratory support around extubation, and the effectiveness of medical interventions. Since the Caffeine Therapy for Apnea of Prematurity (CAP) trial, caffeine has become one of the essential drugs at NICUs. However, the optimal dosage and timing for adequate effectiveness still need to be more conclusive. Previous studies suggest that higher doses of caffeine treatment increase the success rate of extubation. Therefore, we aim to determine whether using a single additional loading dose of caffeine citrate one hour prior to extubation impacts the success rate of extubation.MethodsThe study is an open-label, multicenter randomized clinical trial testing the effectiveness and safety of pre-extubational loading dose of caffeine citrate. Inclusion criteria will be infants born before the 32nd gestational week, before the first extubation attempt after at least 48 hours of mechanical ventilation, and a signed parental informed consent. A total of 226 patients will be randomly allocated to either the experimental or control group. The randomization will be stratified by gestational age and antenatal steroid prophylaxis. Preterm infants in the experimental group will receive an additional intravenous (IV) loading dose (20 mg/kg) of caffeine citrate one hour before the first planned extubation, in addition to the standard dosing regimen (20 mg/kg caffeine citrate IV on the first day of life and 5 to 10 mg/kg IV or orally caffeine citrate each consecutive day). Preterm infants in the control group will receive the standard dosing regimen. The primary outcome will be reintubation within 48 hours.DiscussionA pre-extubational loading dose of caffeine citrate can reduce extubation failure. Obtaining evidence on this feature has the potential to contribute to finding the optimal dosing regimen.Trial registration numberThe study protocol was approved by the Hungarian Ethics Committee for Clinical Pharmacology of the Medical Research Council and National Institute of Pharmacy and Nutrition (OGYÉI/6838-11/2023). ClinicalTrials.gov identifier NCT06401083 Registered 06. May 2024.; EudraCT number: 2022-003202-77.
- Published
- 2025
- Full Text
- View/download PDF
3. Cesarean delivery is associated with lower neonatal mortality among breech pregnancies: a systematic review and meta-analysis of preterm deliveries ≤32 weeks of gestation
- Author
-
Unger, Vivien, Gasparics, Ákos, Nagy, Zsuzsanna, Hernádfői, Márk, Nagy, Rita, Walter, Anna, Farkas, Nelli, Szabó, Miklós, Hegyi, Péter, Garami, Miklós, and Varga, Péter
- Published
- 2024
- Full Text
- View/download PDF
4. The histologic fetal inflammatory response and neonatal outcomes: systematic review and meta-analysis
- Author
-
Kovács, Kinga, Kovács, Őzike Zsuzsanna, Bajzát, Dorina, Imrei, Marcell, Nagy, Rita, Németh, Dávid, Kói, Tamás, Szabó, Miklós, Fintha, Attila, Hegyi, Péter, Garami, Miklós, and Gasparics, Ákos
- Published
- 2024
- Full Text
- View/download PDF
5. The effect of an additional pre-extubational loading dose of caffeine citrate on mechanically ventilated preterm infants (NEOKOFF trial): Study protocol for a multicenter randomized clinical trial.
- Author
-
Kovács, Kinga, Nagy, Rita, Andréka, Lilla, Teutsch, Brigitta, Szabó, Miklós, Varga, Péter, Hegyi, Péter, Hársfalvi, Péter, Ács, Nándor, Harmath, Ágnes, Nádor, Csaba, and Gasparics, Ákos
- Subjects
NEONATAL intensive care units ,RESEARCH protocols ,APNEA of prematurity ,PHARMACOLOGY ,ESSENTIAL drugs ,PREMATURE infants - Abstract
Background: Minimizing the duration of mechanical ventilation is one of the most important therapeutic goals during the care of preterm infants at neonatal intensive care units (NICUs). The rate of extubation failure among preterm infants is between 16% and 40% worldwide. Numerous studies have been conducted on the assessment of extubation suitability, the optimal choice of respiratory support around extubation, and the effectiveness of medical interventions. Since the Caffeine Therapy for Apnea of Prematurity (CAP) trial, caffeine has become one of the essential drugs at NICUs. However, the optimal dosage and timing for adequate effectiveness still need to be more conclusive. Previous studies suggest that higher doses of caffeine treatment increase the success rate of extubation. Therefore, we aim to determine whether using a single additional loading dose of caffeine citrate one hour prior to extubation impacts the success rate of extubation. Methods: The study is an open-label, multicenter randomized clinical trial testing the effectiveness and safety of pre-extubational loading dose of caffeine citrate. Inclusion criteria will be infants born before the 32
nd gestational week, before the first extubation attempt after at least 48 hours of mechanical ventilation, and a signed parental informed consent. A total of 226 patients will be randomly allocated to either the experimental or control group. The randomization will be stratified by gestational age and antenatal steroid prophylaxis. Preterm infants in the experimental group will receive an additional intravenous (IV) loading dose (20 mg/kg) of caffeine citrate one hour before the first planned extubation, in addition to the standard dosing regimen (20 mg/kg caffeine citrate IV on the first day of life and 5 to 10 mg/kg IV or orally caffeine citrate each consecutive day). Preterm infants in the control group will receive the standard dosing regimen. The primary outcome will be reintubation within 48 hours. Discussion: A pre-extubational loading dose of caffeine citrate can reduce extubation failure. Obtaining evidence on this feature has the potential to contribute to finding the optimal dosing regimen. Trial registration number: The study protocol was approved by the Hungarian Ethics Committee for Clinical Pharmacology of the Medical Research Council and National Institute of Pharmacy and Nutrition (OGYÉI/6838-11/2023). ClinicalTrials.gov identifier NCT06401083 Registered 06. May 2024.; EudraCT number: 2022-003202-77. [ABSTRACT FROM AUTHOR]- Published
- 2025
- Full Text
- View/download PDF
6. Investigation of Potential Material Inhomogeneity in the Magnetically Detected Neutron-Irradiation-Generated Structural Degradation of Nuclear Reactor Pressure Vessel Steel
- Author
-
Gábor Vértesy, Antal Gasparics, and Ildikó Szenthe
- Subjects
neutron irradiation ,reactor pressure vessel steel ,magnetic nondestructive evaluation ,magnetic adaptive testing ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
A novel nondestructive method called magnetic adaptive testing has been previously applied to detect the neutron-irradiation-generated structural changes in reactor pressure vessel steel material. This method has been found to be a useful tool for this purpose, and good correlation—as a tendency—has been found between the estimated ductile-to-brittle transition temperature and magnetic parameters. However, a significant scattering of measured points was also observed for the investigated set of Charpy specimens. The main result of the work was that by magnetic selection of samples, the scatter can be notably reduced. As a conclusion, the magnetically measured parameters seemed to be precise and reliable for the detection of embrittlement of the reactor pressure vessel steel, with lower scattering of points than in the conventionally used destructive mechanical characteristics (ductile-to-brittle transition temperature). This result is surprising and needs further verification. The purpose of the present work is to repeat the measurement on irradiated reactor steel blocks. In this work, instead of the DBTT transition temperature, individually measured Vickers hardness (VH) data were used to help characterize the mechanical properties of the material. The so-called “property transformation” is a known and applied technique in the nuclear industry. The mechanical property characterized by the transition temperature cannot be determined individually for each specimen; instead, it can be obtained only on a set of samples by statistical fitting. Therefore, the individually measured Vickers hardness values can be utilized in order to predict the individual transition temperature values by the help of the property transformation technique. In this paper, however, not these derived transition temperature values, but their origins, the Vickers hardness values, are studied in a direct manner. The same behavior of blocks was observed as in the case of Charpy specimens, which is considered to validate the previously published results. As a possible reason for the scattering of points, large magnetic inhomogeneity of samples cut even from the same block was also proved. The magnetic parameters and Vickers hardness correlate well with each other. This result justifies the potential future application of magnetic techniques in practice aimed at the regular inspection of nuclear reactors.
- Published
- 2022
- Full Text
- View/download PDF
7. Machine-Learning Approach to Determine Surface Quality on a Reactor Pressure Vessel (RPV) Steel
- Author
-
James M. Griffin, Jino Mathew, Antal Gasparics, Gábor Vértesy, Inge Uytdenhouwen, Rachid Chaouadi, and Michael E. Fitzpatrick
- Subjects
electro-magnetic ,Barkhausen Noise ,MAT ,surface quality ,imputation ,augmentation ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
Surface quality measures such as roughness, and especially its uncertain character, affect most magnetic non-destructive testing methods and limits their performance in terms of an achievable signal-to-noise ratio and reliability. This paper is primarily focused on an experimental study targeting nuclear reactor materials manufactured from the milling process with various machining parameters to produce varying surface quality conditions to mimic the varying material surface qualities of in-field conditions. From energising a local area electromagnetically, a receiver coil is used to obtain the emitted Barkhausen noise, from which the condition of the material surface can be inspected. Investigations were carried out with the support of machine-learning algorithms, such as Neural Networks (NN) and Classification and Regression Trees (CART), to identify the differences in surface quality. Another challenge often faced is undertaking an analysis with limited experimental data. Other non-destructive methods such as Magnetic Adaptive Testing (MAT) were used to provide data imputation for missing data using other intelligent algorithms. For data reinforcement, data augmentation was used. With more data the problem of ‘the curse of data dimensionality’ is addressed. It demonstrated how both data imputation and augmentation can improve measurement datasets.
- Published
- 2022
- Full Text
- View/download PDF
8. Investigation of the Influence of Neutron Irradiation on Cladded Nuclear Reactor Pressure Vessel Steel Blocks by Magnetic Adaptive Testing
- Author
-
Gábor Vértesy, Antal Gasparics, Ildikó Szenthe, and Inge Uytdenhouwen
- Subjects
neutron irradiation ,reactor pressure vessel steel ,magnetic nondestructive evaluation ,magnetic adaptive testing ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
The influence of neutron irradiation degradation on reactor pressure vessel steel was investigated. Large blocks were irradiated by neutrons in the BR2 reactor at a low irradiation temperature. They were measured by a nondestructive magnetic method, magnetic adaptive testing, before and after the neutron irradiation. It was shown that the modification of the magnetic parameters due to the neutron irradiation was well detectable by this nondestructive method. It was also shown that the influence of neutron irradiation could be detected with a reasonable signal-to-noise ratio through the cladding. The present results are considered as a first step towards the application of magnetic adaptive testing in the nuclear industry.
- Published
- 2022
- Full Text
- View/download PDF
9. Morbidity and mortality trends in very–very low birth weight premature infants in light of recent changes in obstetric care
- Author
-
Varga, Péter, Berecz, Botond, Gasparics, Ákos, Dombi, Zsófia, Varga, Zsuzsa, Jeager, Judit, Magyar, Zsófia, Rigó, János, Jr., Joó, József Gábor, and Kornya, László
- Published
- 2017
- Full Text
- View/download PDF
10. Evaluation of the Embrittlement in Reactor Pressure-Vessel Steels Using a Hybrid Nondestructive Electromagnetic Testing and Evaluation Approach.
- Author
-
Vértesy, Gábor, Rabung, Madalina, Gasparics, Antal, Uytdenhouwen, Inge, Griffin, James, Algernon, Daniel, Grönroos, Sonja, and Rinta-Aho, Jari
- Subjects
ELECTROMAGNETIC testing ,NONDESTRUCTIVE testing ,ADAPTIVE testing ,TRANSITION temperature ,STEEL ,PRESSURIZED water reactors ,NUCLEAR reactors ,EMBRITTLEMENT - Abstract
The nondestructive determination of the neutron-irradiation-induced embrittlement of nuclear reactor pressure-vessel steel is a very important and recent problem. Within the scope of the so-called NOMAD project funded by the Euratom research and training program, novel nondestructive electromagnetic testing and evaluation (NDE) methods were applied to the inspection of irradiated reactor pressure-vessel steel. In this review, the most important results of this project are summarized. Different methods were used and compared with each other. The measurement results were compared with the destructively determined ductile-to-brittle transition temperature (DBTT) values. Three magnetic methods, 3MA (micromagnetic, multiparameter, microstructure and stress analysis), MAT (magnetic adaptive testing), and Barkhausen noise technique (MBN), were found to be the most promising techniques. The results of these methods were in good agreement with each other. A good correlation was found between the magnetic parameters and the DBTT values. The basic idea of the NOMAD project is to use a multi-method/multi-parameter approach and to focus on the synergies that allow us to recognize the side effects, therefore suppressing them at the same time. Different types of machine-learning (ML) algorithms were tested in a competitive manner, and their performances were evaluated. The important outcome of the ML technique is that not only one but several different ML techniques could reach the required precision and reliability, i.e., keeping the DBTT prediction error lower than a ±25 °C threshold, which was previously not possible for any of the NDE methods as single entities. A calibration/training procedure was carried out on the merged outcome of the testing methods with excellent results to predict the transition temperature, yield strength, and mechanical hardness for all investigated materials. Our results, achieved within the NOMAD project, can be useful for the future potential introduction of this (and, in general, any) nondestructive evolution method. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
11. Alterations in SCAI Expression during Cell Plasticity, Fibrosis and Cancer
- Author
-
Gasparics, Ákos, Kökény, Gábor, Fintha, Attila, Bencs, Rita, Mózes, Miklós M., Ágoston, Emese Irma, Buday, Anna, Ivics, Zoltán, Hamar, Péter, Győrffy, Balázs, Rosivall, László, and Sebe, Attila
- Published
- 2018
- Full Text
- View/download PDF
12. Therapeutic Targeting of Fibrotic Epithelial-Mesenchymal Transition–An Outstanding Challenge
- Author
-
Attila Fintha, Ákos Gasparics, László Rosivall, and Attila Sebe
- Subjects
epithelial to mesenchymal transition ,fibrosis ,myofibroblast ,repair ,chronic injury ,Therapeutics. Pharmacology ,RM1-950 - Abstract
Back in 1995, a landmark paper was published, which shaped the fibrosis literature for many years to come. During the characterization of a fibroblast-specific marker (FSP1) in the kidneys, an observation was made, which gave rise to the hypothesis that “fibroblasts in some cases arise from the local conversion of epithelium.” In the following years, epithelial-mesenchymal transition was in the spotlight of fibrosis research, especially in the kidney. However, the hypothesis came under scrutiny following some discouraging findings from lineage tracing experiments and clinical observations. In this review, we provide a timely overview of the current position of the epithelial-mesenchymal transition hypothesis in the context of fibrosis (with a certain focus on renal fibrosis) and highlight some of the potential hurdles and pitfalls preventing therapeutic breakthroughs targeting fibrotic epithelial-mesenchymal transition.
- Published
- 2019
- Full Text
- View/download PDF
13. Interpretation of Nondestructive Magnetic Measurements on Irradiated Reactor Steel Material
- Author
-
Gábor Vértesy, Antal Gasparics, Ildikó Szenthe, and Inge Uytdenhouwen
- Subjects
neutron irradiation embrittlement ,reactor pressure vessel ,magnetic nondestructive evaluation ,magnetic adaptive testing ,ductile to brittle transition temperature ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
Neutron irradiation-generated embrittlement of nuclear pressure vessel steel was inspected by a nondestructive magnetic method, called magnetic adaptive testing (MAT). This method is based on systematic measurement and evaluation of minor magnetic hysteresis loops. Result of MAT measurement was compared with the result of the traditional Charpy measurement. Good correlation was found between these parameters. One of the main findings of the present work is that the considerable part of scatter of points obtained by magnetic measurement can be attributed to local material inhomogeneity. Another important conclusion is that the embrittlement highly depends on the initial local material conditions, i.e., the initial microstructure, which are very different even within the same block of reactor steel material. By taking this into account, the magnetic descriptors obtain more precise determination of the local embrittlement than the traditionally used destructive mechanical parameters from Charpy data.
- Published
- 2021
- Full Text
- View/download PDF
14. Micromagnetic Characterization of Operation-Induced Damage in Charpy Specimens of RPV Steels
- Author
-
Madalina Rabung, Melanie Kopp, Antal Gasparics, Gábor Vértesy, Ildikó Szenthe, Inge Uytdenhouwen, and Klaus Szielasko
- Subjects
neutron irradiation embrittlement ,reactor pressure vessel ,magnetic nondestructive evaluation ,micromagnetic multiparameter microstructure and stress analysis 3MA ,magnetic adaptive testing ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
The embrittlement of two types of nuclear pressure vessel steel, 15Kh2NMFA and A508 Cl.2, was studied using two different methods of magnetic nondestructive testing: micromagnetic multiparameter microstructure and stress analysis (3MA-X8) and magnetic adaptive testing (MAT). The microstructure and mechanical properties of reactor pressure vessel (RPV) materials are modified due to neutron irradiation; this material degradation can be characterized using magnetic methods. For the first time, the progressive change in material properties due to neutron irradiation was investigated on the same specimens, before and after neutron irradiation. A correlation was found between magnetic characteristics and neutron-irradiation-induced damage, regardless of the type of material or the applied measurement technique. The results of the individual micromagnetic measurements proved their suitability for characterizing the degradation of RPV steel caused by simulated operating conditions. A calibration/training procedure was applied on the merged outcome of both testing methods, producing excellent results in predicting transition temperature, yield strength, and mechanical hardness for both materials.
- Published
- 2021
- Full Text
- View/download PDF
15. The Effect of Additional Whole-Body Vibration on Musculoskeletal System in Children with Cerebral Palsy: A Systematic Review and Meta-Analysis of Randomized Clinical Trials.
- Author
-
Pulay, Márk Ágoston, Nagy, Rita, Kói, Tamás, Harnos, Andrea, Zimonyi, Nóra, Garami, Miklós, Gasparics, Ákos, Hegyi, Péter, Túri, Ibolya, and Feketéné Szabó, Éva
- Subjects
CHILDREN with cerebral palsy ,WHOLE-body vibration ,MUSCULOSKELETAL system ,CLINICAL trials ,PEOPLE with cerebral palsy ,CONSTRAINT-induced movement therapy - Abstract
Nowadays, whole-body vibration (WBV) has become increasingly popular as an additional therapy in the intervention of patients with cerebral palsy (CP). However, the impact of WBV remains a subject of debate. Consequently, a systematic review and meta-analysis were undertaken to evaluate the effects of WBV on the musculoskeletal system in children with CP. Randomized controlled trials (RCTs) were sought in the most frequent databases. The intervention studied was WBV combined with conventional physiotherapy (PT) compared with conventional PT as the control; the main outcomes were changes in the musculoskeletal system. Weighted mean differences with 95%CIs were calculated. A random-effects model was applied, and the publication bias was checked using funnel plots. On the basis of the inclusion and exclusion criteria, 16 articles, including 414 patients, were considered in the final analysis. The improvement in walking performance (speed and step length) was statistically significant (p < 0.05), and although there were no significant differences in the further outcomes, a clear positive tendency was visible in the case of improved muscle strength, decreased spasticity, enhanced gross motor functions, and overall stability. Based on the findings, a clear assessment of the usefulness of this intervention cannot be made; nonetheless, due to the promising results, it would be worthwhile to conduct additional RCTs to enhance the available evidence in this field. Due to the wide range of vibration configurations, including varying durations and intensities, it is suggested to establish guidelines and a strategy for the incorporation of this additional treatment. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
16. Analysis of Surface Roughness Influence in Non-Destructive Magnetic Measurements Applied to Reactor Pressure Vessel Steels
- Author
-
Gábor Vértesy, Antal Gasparics, James M. Griffin, Jino Mathew, Michael E. Fitzpatrick, and Inge Uytdenhouwen
- Subjects
magnetic nondestructive evaluation ,magnetic adaptive testing ,magnetic Barkhausen noise measurement ,steel degradation ,surface roughness ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
The influence of surface roughness on magnetic measurements of Reactor Pressure Vessel Steels was investigated by applying two types of magnetic, non-destructive measurement on nuclear reactor pressure vessel steel samples: magnetic adaptive testing (MAT) and magnetic Barkhausen noise measurement (MBN). The surface roughness was modified by primary and secondary machine cutting forces. Different settings of machine cutting produced different surface conditions. It was found that for both measurements a monotonic correlation was found to exist between magnetic parameters and surface roughness. Results of the MAT measurements found that the correlation depends on the speed (i.e., on the applied slew rate) of the magnetizing current. In a similar fashion, results from the MBN method show good agreement with MAT, where the response diminishes with an increase in surface roughness. The results show the importance of accounting for surface condition in the interpretation of results of non-destructive magnetic testing.
- Published
- 2020
- Full Text
- View/download PDF
17. Nondestructive Investigation of Neutron Irradiation Generated Structural Changes of Reactor Steel Material by Magnetic Hysteresis Method
- Author
-
Gábor Vértesy, Antal Gasparics, Inge Uytdenhouwen, Ildikó Szenthe, Ferenc Gillemot, and Rachid Chaouadi
- Subjects
steel degradation ,nuclear reactor pressure vessel ,magnetic NDT ,magnetic adaptive testing ,neutron irradiation ,Mining engineering. Metallurgy ,TN1-997 - Abstract
The neutron irradiation embrittlement of four different types of nuclear pressure vessel materials (three base metals and one weld material) were investigated by a magnetic nondestructive testing method, magnetic adaptive testing (MAT). The method is based on the measurement of minor magnetic hysteresis loops on Charpy specimens irradiated by neutrons in the BR2 reactor. Due to the neutron irradiation, the structure of the material was modified. The Charpy impact method is suitable for destructive characterization of material embrittlement. The results of Charpy impact test measurements at SCK CEN Belgian Nuclear Research Centre were compared with the nondestructively measured magnetic parameters. A definite correlation was found between magnetic descriptors and the ductile-to-brittle transition temperature (DBTT), regardless of the type of material or irradiation condition. The results suggest that this “calibration curve“ can be used to estimate the DBTT from non-destructive measurements.
- Published
- 2020
- Full Text
- View/download PDF
18. Inspection of Local Wall Thinning by Different Magnetic Methods
- Author
-
Vértesy, G., Gasparics, A., and Tomáš, I.
- Published
- 2018
- Full Text
- View/download PDF
19. Characterization and Role of SCAI during Renal Fibrosis and Epithelial-to-Mesenchymal Transition
- Author
-
Fintha, Attila, Gasparics, Ákos, Fang, Lilla, Erdei, Zsuzsa, Hamar, Péter, Mózes, Miklós M., Kökény, Gábor, Rosivall, László, and Sebe, Attila
- Published
- 2013
- Full Text
- View/download PDF
20. Corrigendum to ‘The histologic fetal inflammatory response and neonatal outcomes: systematic review and meta-analysis’: American Journal of Obstetrics and Gynecology, 230/5, (2024), 493-511
- Author
-
Kovács, Kinga, Kovács, Őzike Zsuzsanna, Bajzát, Dorina, Imrei, Marcell, Nagy, Rita, Németh, Dávid, Kói, Tamás, Szabó, Miklós, Fintha, Attila, Hegyi, Péter, Garami, Miklós, and Gasparics, Ákos
- Published
- 2024
- Full Text
- View/download PDF
21. Analysis of Magnetic Nondestructive Measurement Methods for Determination of the Degradation of Reactor Pressure Vessel Steel
- Author
-
Ildikó Szenthe, Gábor Vértesy, Madalina Rabung, James M. Griffin, Antal Gasparics, Melanie Kopp, and Publica
- Subjects
Work (thermodynamics) ,Technology ,micromagnetic multiparameter microstructure and stress analysis 3MA ,Materials science ,Charpy impact test ,02 engineering and technology ,01 natural sciences ,Article ,0103 physical sciences ,General Materials Science ,neutron irradiation embrittlement ,Composite material ,Reactor pressure vessel ,Embrittlement ,010302 applied physics ,Microscopy ,QC120-168.85 ,ductile to brittle transition temperature ,Scattering ,Transition temperature ,QH201-278.5 ,steel degradation ,021001 nanoscience & nanotechnology ,Engineering (General). Civil engineering (General) ,Pressure vessel ,magnetic nondestructive evaluation ,TK1-9971 ,reactor pressure vessel ,Descriptive and experimental mechanics ,Barkhausen noise measurement ,Electrical engineering. Electronics. Nuclear engineering ,magnetic adaptive testing ,TA1-2040 ,0210 nano-technology ,Material properties - Abstract
Nondestructive magnetic measurement methods can be successfully applied to determine the embrittlement of nuclear pressure vessel steel caused by neutron irradiation. It was found in previous works that reasonable correlation could be obtained between the nondestructively measured magnetic parameters and destructively determined ductile-to-brittle transition temperature. However, a large scatter of the measurement points was detected even in the cases of the non-irradiated reference samples. The reason for their scattering was attributed to the local inhomogeneity of material. This conclusion is verified in the present work by applying three different magnetic methods on two sets of Charpy samples made of two different reactor steel materials. It was found that by an optimal magnetic pre-selection of samples, a good, linear correlation can be found between magnetic parameters as well as the ductile-to-brittle transition temperature with low scattering of points. This result shows that neutron irradiation embrittlement depends very much on the local material properties.
- Published
- 2021
22. Numerical calibration of fluxset probe for quantitative eddy current testing
- Author
-
Pávó, József and Gasparics, Antal
- Published
- 1999
- Full Text
- View/download PDF
23. B‐H characteristic extraction using devices with non‐uniform field
- Author
-
Ioan, Daniel, Rebican, Mihai, and Gasparics, Antal
- Published
- 1999
- Full Text
- View/download PDF
24. Endothelial-mesenchymal transition of brain endothelial cells: possible role during metastatic extravasation.
- Author
-
István A Krizbai, Ákos Gasparics, Péter Nagyőszi, Csilla Fazakas, Judit Molnár, Imola Wilhelm, Rita Bencs, László Rosivall, and Attila Sebe
- Subjects
Medicine ,Science - Abstract
Cancer progression towards metastasis follows a defined sequence of events described as the metastatic cascade. For extravasation and transendothelial migration metastatic cells interact first with endothelial cells. Yet the role of endothelial cells during the process of metastasis formation and extravasation is still unclear, and the interaction between metastatic and endothelial cells during transendothelial migration is poorly understood. Since tumor cells are well known to express TGF-β, and the compact endothelial layer undergoes a series of changes during metastatic extravasation (cell contact disruption, cytoskeletal reorganization, enhanced contractility), we hypothesized that an EndMT may be necessary for metastatic extravasation. We demonstrate that primary cultured rat brain endothelial cells (BEC) undergo EndMT upon TGF-β1 treatment, characterized by the loss of tight and adherens junction proteins, expression of fibronectin, β1-integrin, calponin and α-smooth muscle actin (SMA). B16/F10 cell line conditioned and activated medium (ACM) had similar effects: claudin-5 down-regulation, fibronectin and SMA expression. Inhibition of TGF-β signaling during B16/F10 ACM stimulation using SB-431542 maintained claudin-5 levels and mitigated fibronectin and SMA expression. B16/F10 ACM stimulation of BECs led to phosphorylation of Smad2 and Smad3. SB-431542 prevented SMA up-regulation upon stimulation of BECs with A2058, MCF-7 and MDA-MB231 ACM as well. Moreover, B16/F10 ACM caused a reduction in transendothelial electrical resistance, enhanced the number of melanoma cells adhering to and transmigrating through the endothelial layer, in a TGF-β-dependent manner. These effects were not confined to BECs: HUVECs showed TGF-β-dependent SMA expression when stimulated with breast cancer cell line ACM. Our results indicate that an EndMT may be necessary for metastatic transendothelial migration, and this transition may be one of the potential mechanisms occurring during the complex phenomenon known as metastatic extravasation.
- Published
- 2015
- Full Text
- View/download PDF
25. Forward Genetic Screens as Tools to Investigate Role and Mechanisms of EMT in Cancer.
- Author
-
Gasparics, Ákos and Sebe, Attila
- Subjects
- *
WOUND healing , *GENETIC mutation , *ONCOGENES , *GENETIC testing , *DRUG resistance , *EPITHELIAL-mesenchymal transition , *GENOMES , *TUMOR suppressor genes , *CRISPRS , *PHENOTYPES - Abstract
Simple Summary: Forward genetic screens link genome modifications to phenotypes, and have been successfully employed to identify oncogenes, tumor suppressor genes and genes involved in metastasis or therapy resistance. In particular, transposon-based insertional mutagenesis screens and CRISPR-based screens are versatile and easy-to-use tools employed in recent years to discover and identify novel cancer-related mechanisms. In this review, we present the contribution of forward genetic screens to our understanding of how EMT is regulated and how it is involved in various aspects of cancer. Epithelial–mesenchymal transition (EMT) is a process of cellular plasticity regulated by complex signaling networks. Under physiological conditions, it plays an important role in wound healing and organ repair. Its importance for human disease is given by its central role in chronic fibroproliferative diseases and cancer, which represent leading causes of death worldwide. In tumors, EMT is involved in primary tumor growth, metastasis and therapy resistance. It is therefore a major requisite to investigate and understand the role of EMT and the mechanisms leading to EMT in order to tackle these diseases therapeutically. Forward genetic screens link genome modifications to phenotypes, and have been successfully employed to identify oncogenes, tumor suppressor genes and genes involved in metastasis or therapy resistance. In particular, transposon-based insertional mutagenesis screens and CRISPR-based screens are versatile and easy-to-use tools applied in recent years to discover and identify novel cancer-related mechanisms. Here, we review the contribution of forward genetic screens to our understanding of how EMT is regulated and how it is involved in various aspects of cancer. Based on the current literature, we propose these methods as additional tools to investigate EMT. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
26. Investigation of Potential Material Inhomogeneity in the Magnetically Detected Neutron-Irradiation-Generated Structural Degradation of Nuclear Reactor Pressure Vessel Steel.
- Author
-
Vértesy, Gábor, Gasparics, Antal, and Szenthe, Ildikó
- Subjects
NUCLEAR pressure vessels ,NUCLEAR reactors ,RESEARCH reactors ,MECHANICAL behavior of materials ,TRANSITION temperature ,VICKERS hardness ,ADAPTIVE testing ,EMBRITTLEMENT - Abstract
A novel nondestructive method called magnetic adaptive testing has been previously applied to detect the neutron-irradiation-generated structural changes in reactor pressure vessel steel material. This method has been found to be a useful tool for this purpose, and good correlation—as a tendency—has been found between the estimated ductile-to-brittle transition temperature and magnetic parameters. However, a significant scattering of measured points was also observed for the investigated set of Charpy specimens. The main result of the work was that by magnetic selection of samples, the scatter can be notably reduced. As a conclusion, the magnetically measured parameters seemed to be precise and reliable for the detection of embrittlement of the reactor pressure vessel steel, with lower scattering of points than in the conventionally used destructive mechanical characteristics (ductile-to-brittle transition temperature). This result is surprising and needs further verification. The purpose of the present work is to repeat the measurement on irradiated reactor steel blocks. In this work, instead of the DBTT transition temperature, individually measured Vickers hardness (VH) data were used to help characterize the mechanical properties of the material. The so-called "property transformation" is a known and applied technique in the nuclear industry. The mechanical property characterized by the transition temperature cannot be determined individually for each specimen; instead, it can be obtained only on a set of samples by statistical fitting. Therefore, the individually measured Vickers hardness values can be utilized in order to predict the individual transition temperature values by the help of the property transformation technique. In this paper, however, not these derived transition temperature values, but their origins, the Vickers hardness values, are studied in a direct manner. The same behavior of blocks was observed as in the case of Charpy specimens, which is considered to validate the previously published results. As a possible reason for the scattering of points, large magnetic inhomogeneity of samples cut even from the same block was also proved. The magnetic parameters and Vickers hardness correlate well with each other. This result justifies the potential future application of magnetic techniques in practice aimed at the regular inspection of nuclear reactors. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
27. Local Structure and Eddy Current Loss on the Surface of Carbon-steels in the Vicinity of Laser Marking
- Author
-
Kalincsák, Z., Takács, J., Vértesy, G., and Gasparics, A.
- Published
- 2004
- Full Text
- View/download PDF
28. Transient eddy current analysis of pulsed eddy current testing by finite element method
- Author
-
Tsuboi, Hajime, Seshima, Norio, Sebestyen, Imre, Pavo, Josef, Gyimothy, Szabolcs, and Gasparics, Antal
- Subjects
Electromagnetism -- Research ,Business ,Electronics ,Electronics and electrical industries - Abstract
Transient eddy current analysis of pulsed eddy current testing was performed by time-stepping method and Fourier transform method. The characteristics of two methods were evaluated by using a simple model. The accuracy was examined by the comparison of calculated and measured data. The calculated results of the two methods provided good agreement with measured data. However, it was clear that the Fourier transform method provided higher accuracy of amplitude than the time-stepping method. As a three-dimensional problem of pulsed eddy current testing, the TEAM Workshop Problem 27 was analyzed by an edge-element finite element method. Index Terms--Eddy current analysis, eddy current testing, finite element method (FEM).
- Published
- 2004
29. Machine-Learning Approach to Determine Surface Quality on a Reactor Pressure Vessel (RPV) Steel.
- Author
-
Griffin, James M., Mathew, Jino, Gasparics, Antal, Vértesy, Gábor, Uytdenhouwen, Inge, Chaouadi, Rachid, and Fitzpatrick, Michael E.
- Subjects
MACHINE learning ,PRESSURE vessels ,NUCLEAR reactor materials ,DATA augmentation ,MAGNETIC testing - Abstract
Surface quality measures such as roughness, and especially its uncertain character, affect most magnetic non-destructive testing methods and limits their performance in terms of an achievable signal-to-noise ratio and reliability. This paper is primarily focused on an experimental study targeting nuclear reactor materials manufactured from the milling process with various machining parameters to produce varying surface quality conditions to mimic the varying material surface qualities of in-field conditions. From energising a local area electromagnetically, a receiver coil is used to obtain the emitted Barkhausen noise, from which the condition of the material surface can be inspected. Investigations were carried out with the support of machine-learning algorithms, such as Neural Networks (NN) and Classification and Regression Trees (CART), to identify the differences in surface quality. Another challenge often faced is undertaking an analysis with limited experimental data. Other non-destructive methods such as Magnetic Adaptive Testing (MAT) were used to provide data imputation for missing data using other intelligent algorithms. For data reinforcement, data augmentation was used. With more data the problem of 'the curse of data dimensionality' is addressed. It demonstrated how both data imputation and augmentation can improve measurement datasets. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
30. Investigation of the Influence of Neutron Irradiation on Cladded Nuclear Reactor Pressure Vessel Steel Blocks by Magnetic Adaptive Testing.
- Author
-
Vértesy, Gábor, Gasparics, Antal, Szenthe, Ildikó, and Uytdenhouwen, Inge
- Subjects
NUCLEAR pressure vessels ,ADAPTIVE testing ,MAGNETIC testing ,NEUTRON irradiation ,NUCLEAR industry ,PRESSURE vessels - Abstract
The influence of neutron irradiation degradation on reactor pressure vessel steel was investigated. Large blocks were irradiated by neutrons in the BR2 reactor at a low irradiation temperature. They were measured by a nondestructive magnetic method, magnetic adaptive testing, before and after the neutron irradiation. It was shown that the modification of the magnetic parameters due to the neutron irradiation was well detectable by this nondestructive method. It was also shown that the influence of neutron irradiation could be detected with a reasonable signal-to-noise ratio through the cladding. The present results are considered as a first step towards the application of magnetic adaptive testing in the nuclear industry. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
31. Calibration of Fluxset sensors for the measurement of spatially strongly inhomogeneous magnetic fields
- Author
-
Pávó, József, Gasparics, Antal, Sebestyén, Imre, and Vértesy, Gábor
- Published
- 2004
- Full Text
- View/download PDF
32. Seasonal changes of fulvic acid, Ca and Mg concentrations of water samples collected above and in the Béke Cave of the Aggtelek karst system (Hungary)
- Author
-
Tatár, Enikö, Mihucz, Victor G., Zámbó, László, Gasparics, Tibor, and Záray, Gyula
- Published
- 2004
- Full Text
- View/download PDF
33. Hyphenated technique for investigation of nickel complexation by citric acid in xylem sap of cucumber plants
- Author
-
Gasparics, Tibor, Mihucz, Victor G, Tatár, Enikö, and Záray, Gyula
- Published
- 2002
- Full Text
- View/download PDF
34. Interpretation of Nondestructive Magnetic Measurements on Irradiated Reactor Steel Material.
- Author
-
Vértesy, Gábor, Gasparics, Antal, Szenthe, Ildikó, Uytdenhouwen, Inge, Invernizzi, Stefano, and Lacidogna, Giuseppe
- Subjects
NUCLEAR reactor materials ,MAGNETIC measurements ,NUCLEAR pressure vessels ,STEEL walls ,MAGNETIC testing ,NEUTRON irradiation ,NUCLEAR reactors ,EMBRITTLEMENT - Abstract
Featured Application: In this paper, the application of a nondestructive magnetic testing method is analyzed for neutron irradiation-generated embrittlement of nuclear pressure vessel materials. It was found that in spite of the big scatter of measurement points, the degradation of reactor pressure vessel steel can be successfully predicted by this technique. Furthermore, it turned out that the embrittlement highly depends on the local material conditions, which was found to be very different even within the same block of reactor steel material. This implicates different trajectories of their neutron irradiation induced degradation, as well as identifiable differences in the outcomes of their nondestructive evaluation. The magnetic descriptor results add reliable and precise determination of local embrittlement in the material than the traditionally used destructive mechanical parameters, so the results can be helpful for the future practical application of this technique for regular inspection of nuclear reactors. Neutron irradiation-generated embrittlement of nuclear pressure vessel steel was inspected by a nondestructive magnetic method, called magnetic adaptive testing (MAT). This method is based on systematic measurement and evaluation of minor magnetic hysteresis loops. Result of MAT measurement was compared with the result of the traditional Charpy measurement. Good correlation was found between these parameters. One of the main findings of the present work is that the considerable part of scatter of points obtained by magnetic measurement can be attributed to local material inhomogeneity. Another important conclusion is that the embrittlement highly depends on the initial local material conditions, i.e., the initial microstructure, which are very different even within the same block of reactor steel material. By taking this into account, the magnetic descriptors obtain more precise determination of the local embrittlement than the traditionally used destructive mechanical parameters from Charpy data. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
35. Micromagnetic Characterization of Operation-Induced Damage in Charpy Specimens of RPV Steels.
- Author
-
Rabung, Madalina, Kopp, Melanie, Gasparics, Antal, Vértesy, Gábor, Szenthe, Ildikó, Uytdenhouwen, Inge, Szielasko, Klaus, Lee, Jinyi, and Lee, Hoyong
- Subjects
NEUTRON irradiation ,NUCLEAR pressure vessels ,MAGNETIC testing ,DEGRADATION of steel ,NUCLEAR reactors ,ADAPTIVE testing ,EMBRITTLEMENT - Abstract
Featured Application: In this study, the influence of neutron irradiation on the mechanical properties of nuclear pressure vessel materials is investigated using two independent methods of nondestructive magnetic testing. A correlation was found between magnetic characteristics and neutron irradiation-induced damage, regardless of the applied measurement technique. Additionally, by merging the outcome of both testing methods and applying a calibration/training procedure, the damage to reactor steel was successfully predicted. The results are helpful for the potential future practical application of these techniques to the regular inspection of nuclear reactors. The embrittlement of two types of nuclear pressure vessel steel, 15Kh2NMFA and A508 Cl.2, was studied using two different methods of magnetic nondestructive testing: micromagnetic multiparameter microstructure and stress analysis (3MA-X8) and magnetic adaptive testing (MAT). The microstructure and mechanical properties of reactor pressure vessel (RPV) materials are modified due to neutron irradiation; this material degradation can be characterized using magnetic methods. For the first time, the progressive change in material properties due to neutron irradiation was investigated on the same specimens, before and after neutron irradiation. A correlation was found between magnetic characteristics and neutron-irradiation-induced damage, regardless of the type of material or the applied measurement technique. The results of the individual micromagnetic measurements proved their suitability for characterizing the degradation of RPV steel caused by simulated operating conditions. A calibration/training procedure was applied on the merged outcome of both testing methods, producing excellent results in predicting transition temperature, yield strength, and mechanical hardness for both materials. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
36. High sensitivity magnetic field sensor
- Author
-
Vértesy, G, Gasparics, A, and Szöllősy, J
- Published
- 2000
- Full Text
- View/download PDF
37. Influence of the core material polishing on the Fluxset sensor's operation
- Author
-
Vértesy, G, Gasparics, A, Vértesy, Z, and Tóth-Kádár, E
- Published
- 2000
- Full Text
- View/download PDF
38. Determination of trace elements in Antarctic krill samples by inductively coupled atomic emission and graphite furnace atomic absorption spectrometry
- Author
-
Gasparics, Tibor, Martı́nez, Rosa Marı́a Garcinuño, Caroli, Sergio, and Záray, Gyula
- Published
- 2000
- Full Text
- View/download PDF
39. Analysis of Surface Roughness Influence in Non-Destructive Magnetic Measurements Applied to Reactor Pressure Vessel Steels.
- Author
-
Vértesy, Gábor, Gasparics, Antal, Griffin, James M., Mathew, Jino, Fitzpatrick, Michael E., and Uytdenhouwen, Inge
- Subjects
SURFACE roughness ,PRESSURE vessels ,MAGNETIC measurements ,SURFACE analysis ,STEEL walls ,NUCLEAR pressure vessels ,PRESSURIZED water reactors ,NUCLEAR reactors - Abstract
Featured Application: In this paper, the influence of surface roughness is analyzed using two methods (Magnetic adaptive testing and Barkhausen noise measurement) of magnetic non-destructive testing (NDT). The influence of surface roughness can present a serious problem in magnetic NDT, when degradation of structural components of machineries is tested. Our purpose was to investigate the influence of surface roughness on the magnetic parameters, but in the light of our result—considering the unambiguous monotonic correlation between these quantities—it would also be possible to derive the surface roughness from magnetic parameters and to substitute the measurements of R
a . Our results can be helpful for the future practical application of this technique. The influence of surface roughness on magnetic measurements of Reactor Pressure Vessel Steels was investigated by applying two types of magnetic, non-destructive measurement on nuclear reactor pressure vessel steel samples: magnetic adaptive testing (MAT) and magnetic Barkhausen noise measurement (MBN). The surface roughness was modified by primary and secondary machine cutting forces. Different settings of machine cutting produced different surface conditions. It was found that for both measurements a monotonic correlation was found to exist between magnetic parameters and surface roughness. Results of the MAT measurements found that the correlation depends on the speed (i.e., on the applied slew rate) of the magnetizing current. In a similar fashion, results from the MBN method show good agreement with MAT, where the response diminishes with an increase in surface roughness. The results show the importance of accounting for surface condition in the interpretation of results of non-destructive magnetic testing. [ABSTRACT FROM AUTHOR]- Published
- 2020
- Full Text
- View/download PDF
40. The Prognosis of Preterm Infants Born at the Threshold of Viability: Fog Over the Gray Zone - Population-Based Studies of Extremely Preterm Infants.
- Author
-
Fanczal, Eszter, Berecz, Botond, Szijártó, Annamária, Gasparics, Ákos, and Varga, Péter
- Published
- 2020
- Full Text
- View/download PDF
41. Survival and early complications of preterm infants with birthweight less than 500 grams during a 10-year period in Hungary.
- Author
-
Varga, Péter, Berecz, Botond, Magyar, Zsófia, Pete, Barbara, Romicsné Görbe, Éva, Dombi, Zsófia Anna, Sassi, Lilla, Fanczal, Eszter, Ács, Nándor, Kornya, László, Joó, József Gábor, Valek, Andrea, Harmath, Ágnes, and Gasparics, Ákos
- Subjects
PREMATURE infants ,BIRTH weight ,DATA analysis ,GESTATIONAL age ,STEROIDS - Abstract
Background: There are limited data available on the survival and early complications of preterm infants with less than 500 g birthweight. To estimate the outcomes for these infants, it is important for caregivers to be aware of perinatal factors that may affect survival.Objectives: We assessed the mortality and certain early complications of preterm infants born with less than 500 g in Hungary between 2006 and 2015.Methods: We reviewed data of 486 infants from the database of the Hungarian Central Statistical Office and in parallel of 407 infants from the "NICU database." The study period was divided into two epochs: 2006-2010 and 2011-2015.Results: The survival was 27.1% in the first epoch and 39.1% in the second epoch, and the incidence of early complications was slightly higher in the second epoch. In the surviving group (first and second epoch combined), gestational age (25.1 vs 23.7 weeks), birthweight (458 vs 447 g) antenatal steroid treatment (66.3% vs 52.3%), surfactant therapy (95.1% vs 84.3%), median Apgar scores (6 vs 3 and 8 vs 5 at 1 and 5 minutes, respectively) and proportion of caesarean delivery (89.3% versus 68.5%) were higher than in the non-surviving group (first and second epoch combined). The proportion of multiple births was lower in the surviving group (15.7% vs 33.4%).Conclusions: Survival of infants with less than 500 g improved between 2006-2010 and 2011-2015 in Hungary. The slightly higher occurrence of early complications might be associated with improving survival. [ABSTRACT FROM AUTHOR]- Published
- 2020
- Full Text
- View/download PDF
42. Therapeutic Targeting of Fibrotic Epithelial-Mesenchymal Transition–An Outstanding Challenge.
- Author
-
Fintha, Attila, Gasparics, Ákos, Rosivall, László, and Sebe, Attila
- Subjects
RENAL fibrosis ,FIBROSIS ,KIDNEYS - Abstract
Back in 1995, a landmark paper was published, which shaped the fibrosis literature for many years to come. During the characterization of a fibroblast-specific marker (FSP1) in the kidneys, an observation was made, which gave rise to the hypothesis that "fibroblasts in some cases arise from the local conversion of epithelium." In the following years, epithelial-mesenchymal transition was in the spotlight of fibrosis research, especially in the kidney. However, the hypothesis came under scrutiny following some discouraging findings from lineage tracing experiments and clinical observations. In this review, we provide a timely overview of the current position of the epithelial-mesenchymal transition hypothesis in the context of fibrosis (with a certain focus on renal fibrosis) and highlight some of the potential hurdles and pitfalls preventing therapeutic breakthroughs targeting fibrotic epithelial-mesenchymal transition. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
43. Endothelial-mesenchymal transition of brain endothelial cells: possible role during metastatic extravasation
- Author
-
Attila Sebe, Judit Molnár, Csilla Fazakas, Péter Nagyőszi, Imola Wilhelm, Rita Bencs, Ákos Gasparics, László Rosivall, and István A. Krizbai
- Subjects
Pathology ,Gene Expression ,lcsh:Medicine ,Metastasis ,Mice ,Phosphorylation ,Neoplasm Metastasis ,lcsh:Science ,Melanoma ,Cells, Cultured ,Multidisciplinary ,biology ,Tight junction ,Brain ,Adherens Junctions ,Extravasation ,Up-Regulation ,Benzamides ,MCF-7 Cells ,Signal Transduction ,Research Article ,medicine.medical_specialty ,Epithelial-Mesenchymal Transition ,Down-Regulation ,Dioxoles ,Cell Line ,Adherens junction ,Transforming Growth Factor beta1 ,Cell Line, Tumor ,medicine ,Human Umbilical Vein Endothelial Cells ,Animals ,Humans ,Epithelial–mesenchymal transition ,Rats, Wistar ,Mesenchymal stem cell ,lcsh:R ,Transendothelial and Transepithelial Migration ,Correction ,Endothelial Cells ,medicine.disease ,Actins ,Rats ,Fibronectin ,Gene Expression Regulation ,Cell culture ,Culture Media, Conditioned ,biology.protein ,Cancer research ,lcsh:Q - Abstract
Cancer progression towards metastasis follows a defined sequence of events described as the metastatic cascade. For extravasation and transendothelial migration metastatic cells interact first with endothelial cells. Yet the role of endothelial cells during the process of metastasis formation and extravasation is still unclear, and the interaction between metastatic and endothelial cells during transendothelial migration is poorly understood. Since tumor cells are well known to express TGF-β, and the compact endothelial layer undergoes a series of changes during metastatic extravasation (cell contact disruption, cytoskeletal reorganization, enhanced contractility), we hypothesized that an EndMT may be necessary for metastatic extravasation. We demonstrate that primary cultured rat brain endothelial cells (BEC) undergo EndMT upon TGF-β1 treatment, characterized by the loss of tight and adherens junction proteins, expression of fibronectin, β1-integrin, calponin and α-smooth muscle actin (SMA). B16/F10 cell line conditioned and activated medium (ACM) had similar effects: claudin-5 down-regulation, fibronectin and SMA expression. Inhibition of TGF-β signaling during B16/F10 ACM stimulation using SB-431542 maintained claudin-5 levels and mitigated fibronectin and SMA expression. B16/F10 ACM stimulation of BECs led to phosphorylation of Smad2 and Smad3. SB-431542 prevented SMA up-regulation upon stimulation of BECs with A2058, MCF-7 and MDA-MB231 ACM as well. Moreover, B16/F10 ACM caused a reduction in transendothelial electrical resistance, enhanced the number of melanoma cells adhering to and transmigrating through the endothelial layer, in a TGF-β-dependent manner. These effects were not confined to BECs: HUVECs showed TGF-β-dependent SMA expression when stimulated with breast cancer cell line ACM. Our results indicate that an EndMT may be necessary for metastatic transendothelial migration, and this transition may be one of the potential mechanisms occurring during the complex phenomenon known as metastatic extravasation.
- Published
- 2015
44. Trends in Mortality and Morbidity in Infants Under 500 Grams Birthweight: Observations from Our Neonatal Intensive Care Unit (NICU).
- Author
-
Varga, Péter, Berecz, Botond, Pete, Barbara, Kollár, Tímea, Magyar, Zsófia, Jeager, Judit, Görbe, Éva Romicsné, Rigó, János, Joó, Gábor József, and Gasparics, Ákos
- Published
- 2018
- Full Text
- View/download PDF
45. MRTFs‐ master regulators of EMT.
- Author
-
Gasparics, Ákos and Sebe, Attila
- Abstract
Recent evidence implicates the myocardin‐related transcription factors (MRTFs) as key mediators of the phenotypic plasticity leading to the conversion of various cell types into myofibroblasts. This review highlights the function of MRTFs during development, fibrosis and cancer, and the role of MRTFs during epithelial–mesenchymal transitions (EMTs) underlying these processes. EMT is a sequentially orchestrated process where cells undergo a rearrangement of their cell contacts and activate a fibrogenic and myogenic expression program. MRTFs interact with and regulate the major signaling pathways and the expression of key markers and transcription factors involved in EMT. These functions indicate a central role for MRTFs in controlling the process of EMT.
Developmental Dynamics 247:396–404, 2018 . © 2017 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]- Published
- 2018
- Full Text
- View/download PDF
46. 2. Hungarian in Slovenia: An Overview of a Language in Context
- Author
-
Kolláth, Anna, Horvat, Livija, Gróf, Annamária, Gasparics, Judit, Laakso, Johanna, and Berényi-Kiss, Hajnalka
- Subjects
European Projects -- FP7 (euprojects1) -- OpenAire (euprojects1.1) -- Socio-economic sciences and the humanities (euprojects1.1.7) ,Hungarian in Slovenia, Hungarian, language contact, multilingualism, minority language - Abstract
During the initial stage of the research project ELDIA (European Language Diversity for All) in 2010, "structured context analyses" of each speaker community at issue were prepared. These context analyses will act as a starting point for further deepened research by linguists, sociologists and lawyers. Thus, they will form the basis of further case-specific reports and the comparative report which will be the main outcome of the whole project. However, as these will be available for interested readers only at the end of the project, we wanted to publish shorter versions summarising our work so far already at this stage, thus providing up-to-date information for both the academic community and stakeholder groups. This paper, based on the context analysis by Anna Kolláth, Judit Gasparics, Annamária Gróf and Livija Horvat, gives a brief and up-to-date overview of the status of and research about Hungarian in Slovenia. As all papers appearing in the series Working Papers in European Language Diversity, these context analyses have been subject to an anonymous peer-reviewing process. Whenever the present document is referred to, due reference to the author and the ELDIA project should be made. For more information about the ELDIA project see http://www.eldia-project.org/.
- Published
- 2011
47. Inspection of diesel engine injectors by several electromagnetic nondestructive methods.
- Author
-
Vértesy, G., Gasparics, A., Balassa, P., Mészáros, I., and Tomáš, I.
- Subjects
- *
ELECTROMAGNETIC testing , *NONDESTRUCTIVE testing , *DIESEL motors , *EDDY current testing , *MAGNETIC hysteresis - Abstract
Improved eddy current techniques and a method of magnetic hysteresis measurement were applied for nondestructive inspection of thickness of the hardened surface layer of the steel injectors of diesel engines. A monotonic correlation was found with enough sensitivity and acceptable signal/noise ratio between the electromagnetic parameters and the thickness of the layer. Both the hysteresis and the eddy current methods show very similar types of the correlation. Based on these results, practical application of these novel methods can be realized instead of the presently used destructive tests for inspection of the steel injectors of diesel engines. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
48. Defect Reconstruction in ECT via Neural Networks
- Author
-
FORMISANO, Alessandro, A. GASPARICS, F. C. MORABITO, Formisano, Alessandro, A., Gasparic, and F. C., Morabito
- Published
- 1999
49. High Frequency Models for the NDT Magnetic Field Sensors
- Author
-
D. IOAN, A. GASPARICS, I. MUNTEANU, M. REBICAN, FORMISANO, Alessandro, D. Lesselier and A. Razek, D., Ioan, Formisano, Alessandro, A., Gasparic, I., Munteanu, and M., Rebican
- Subjects
electromagnetic analysis ,Eddy Current Testing - Abstract
The following effects of an NDT magnetic field sensor were modeled: internal impedance of the driving source, capacitive effects between coils, ohmic resistance of coils, voltage induced in coils, magnetic flux leakage between coils, nonlinear magnetic characteristic of the core including hysteresis, 3D non-uniformity of the magnetic field and eddy currents in the core. The paper presented an effective parameter extraction procedure for each effect mentioned above. The main original contribution of the paper consists in the method to model simultaneously eddy currents, hysteresis and parasitic capacitive effects which become important at high frequency in all electromagnetic devices. A SPICE nonlinear equivalent circuit of the FLUXSET sensor incorporating all these effects is proposed. The lumped circuit parameters are extracted from the field equations solution. Eddy currents are modeled by an RL chain magnetic scheme and hysteresis, which in this case prevails, is modeled by an electric inductance computed with the Chua-Stromsmoe method. For the capacitive effects, instead of the classical II approximation of a distributed RC line, based on two transverse capacitances C/2 connected at the two terminals, a more sophisticated approximation is proposed in the paper. Using SPICE simulation of the extracted circuit, good agreement with the experimental data was obtained. The proposed method is able to determine the frequency bandwidth of a newly designed FLUXSET sensor.
- Published
- 1999
50. Detection of low density magnetic nanoparticles by Fluxset type magnetic probe.
- Author
-
Vértesy, Gábor, Gasparics, Antal, Pávó, József, and Gyimóthy, Szabolcs
- Subjects
- *
MAGNETIC sensors , *MAGNETIC nanoparticles , *WEAK interactions (Nuclear physics) , *SIGNAL-to-noise ratio , *MAGNETIZATION - Abstract
Fluxset magnetic sensor based probes with a double exciting coil system have been developed for detecting weakly interacting, low mass and small size magnetic particles for biomedical application. The probe measures the magnetic response of particles to an AC excitation. Measurements were carried out on samples containing 20, 30 and 40 nm size nanoparticles, which were embedded in a cylinder containing aguar-aguar. It was shown that the probe can detect nanoparticles of 20 nm size if their concentration is at least 0.06 mg/mm3 from a distance of 1 mm with reliable signal to noise ratio. The probe detection was found to be improved after magnetization of particles. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.