Ewa Stepien

Ewa Stepien
Jagiellonian University | UJ · Institute of Physics

Professor

About

241
Publications
49,944
Reads
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3,375
Citations
Introduction
I am a leading scientist in fields of laboratory medicine and nanomedicine. I am a head of Department of Medical Physics in the Institute of Physics at Jagiellonian University. Joining my experience as a clinical scientist (specialty in laboratory medical genetics) with molecular biology background, I conduct my activity in the Extracellular Vesicle (EV) field for diagnostics and treatment. In basic research, my group aims to reveal mechanisms of EV internalization to endothelial cells. We are working on the development of new tools for EV detection and characterization in vascular medicine. In collaboration with nuclear physicists, I am working on the application of molecular imaging (PALS) methods for cancer research. We are successfully using miRNomic, metabolomic and glycomic methods.
Additional affiliations
October 2017 - present
Jagiellonian University
Position
  • Head of Department
August 2014 - present
Jagiellonian University
Position
  • Professor (Associate)
Description
  • my activity treats nanotechnology in laboratory medicine
October 2013 - August 2014
Jagiellonian University
Position
  • Professor (Assistant)
Description
  • my current project treats the role of intercellular communication in diabetic vascular complications
Education
October 2009 - May 2011
Poznan University of Medical Sciences
Field of study
  • laboratory genetics
October 1992 - February 1997
Jagiellonian University
Field of study
  • postgraduate studies in cell biology, "Factors influencing neutites outgrowth” promoter: Prof. Włodzimierz Korohoda
October 1987 - June 1992
Jagiellonian University
Field of study
  • graduate studies in molecular biology, “Evaluation of methods for neurons isolation and culturing” promoter: Prof. Włodzimierz Korohoda

Publications

Publications (241)
Article
Full-text available
The aim of this study was to check the relationship between the density of urinary EVs, their size distribution, and the progress of early renal damage in type 2 diabetic patients (DMt2). Patients were enrolled to this study, and glycated hemoglobin (HbA1c) below 7% was a threshold for properly controlled diabetic patients (CD) and poorly controlle...
Article
Full-text available
Among the various biomarkers that are used to diagnose or monitor disease, extracellular vesicles (EVs) represent one of the most promising targets in the development of new therapeutic strategies and the application of new diagnostic methods. The detection of circulating platelet-derived microvesicles (PMVs) is a considerable challenge for laborat...
Article
Elevated levels of circulating microparticles (MPs) have been reported in patients with acute myocardial infarction (AMI) and coronary artery disease. Platelet activation and inflammation have been recognized during AMI and stable angina (SA). We hypothesize that the origin and count of MPs in AMI and SA patients are related to markers of inflammat...
Article
Full-text available
Disruption of the intercellular interactions between endothelial cells leads to endothelial dysfunction. The role of nanoparticles in plasma membrane stability, actin cytoskeleton organization and intercellular junctions is unclear. Human umbilical vein endothelial cells were treated with zinc oxide NPs in vitro. Cell shape, adhesiveness and plasma...
Article
Full-text available
Background: Coronary artery occlusion is not always manifested with ST-elevation and some patients can have patent coronary vessel. Aims: We evaluated circulating microRNA profile to discriminate subjects with infarctrelated artery (IRA) occlusion. Methods and results: Patients (n = 43) with uncomplicated ACS and positive troponins were classified...
Article
Objective: This paper reports on the implementation and shows examples of the use of the ProTheRaMon framework for simulating the delivery of proton therapy treatment plans and range monitoring using positron emission tomography (PET). ProTheRaMon offers complete processing of proton therapy treatment plans, patient CT geometries, and intra-treatm...
Article
Full-text available
The image of positronium properties created in the patient’s body during PET examination tells about the inter- and intra-molecular structure of the tissue and the concentration of bio-active molecules in the tissue [ 2 – 4 ]. In this article, we advocate the opinion that total-body PET systems, thanks to their high imaging sensitivity and high tim...
Article
Full-text available
Extracellular vesicles, especially the larger fraction (LEVs – large extracellular vesicles), are believed to be an important means of intercellular communication. Earlier studies on LEVs have shown their healing properties, especially in the vascular cells of diabetic patients. Uptake of LEVs by endothelial cells and internalization of their cargo...
Article
Full-text available
Time-of-flight secondary ion mass spectrometry (TOF-SIMS) with the Bi3⁺ liquid metal ion gun was used to investigate the content of lipids and amino acids (Aas) in extracellular vesicles (EVs). We induced metabolic changes in human pancreatic β-cells by stimulation with high glucose concentrations (35 mM) and tested the hypothesis of hyperglycemia...
Article
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Micro-computed tomography (micro-CT) provides numerous opportunities in biomedical research. It allows the examination of samples in a non-destructive manner and visualization of the inner structures of various biological and nonbiological objects. This study was conducted to evaluate the potential of micro-CT scanner in the assessment of heavy met...
Preprint
It was recently demonstrated that newly invented positronium imaging may be used for improving cancer diagnostics by providing additional information about tissue pathology with respect to the standardized uptake value currently available in positron emission tomography (PET). Positronium imaging utilizes the properties of positronium atoms, which...
Preprint
It was recently demonstrated that newly invented positronium imaging may be used for improving cancer diagnostics by providing additional information about tissue pathology with respect to the standardized uptake value currently available in positron emission tomography (PET). Positronium imaging utilizes properties of a positronium atoms, which ar...
Article
Full-text available
In this review article, we present arguments demonstrating that the advent of high sensitivity total-body PET systems and the invention of the method of positronium imaging , open realistic perspectives for the application of positronium as a biomarker for in-vivo assessment of the degree of hypoxia. Hypoxia is a state or condition, in which the av...
Article
Full-text available
Extracellular vesicles (EVs) are nano- and micro-sized double-layered membrane entities derived from most cell types and released into biological fluids. Biological properties (cell-uptake, biocompatibility), and chemical (composition, structure) or physical (size, density) characteristics make EVs a good candidate for drug delivery systems (DDS)....
Article
Full-text available
Positron emission tomography (PET) imaging is the most quantitative modality for assessing disease activity at the molecular and cellular levels, and therefore, it allows monitoring its course and determining the efficacy of various therapeutic interventions. In this scientific communication, we describe the unparalleled and revolutionary impact of...
Preprint
Full-text available
In vivo assessment of cancer and precise location of altered tissues at initial stages of molecular disorders are important diagnostic challenges. Positronium is copiously formed in the free molecular spaces in the patient's body during positron emission tomography (PET). The positronium properties vary according to the size of inter- and intramole...
Preprint
Full-text available
Extracellular vesicles, namely those larger ones - Ectosomes (Ect), are thought to be important cell-to-cell communication medium. Ect are considered as a potential therapeutic for type-1 and type-2 diabetes mellitus. Ect can be internalized by endothelial cells and, owing to their cargo, they modulate targeted cell behavior. Under hyperglycemic co...
Article
In vivo assessment of cancer and precise location of altered tissues at initial stages of molecular disorders are important diagnostic challenges. Positronium is copiously formed in the free molecular spaces in the patient’s body during positron emission tomography (PET). The positronium properties vary according to the size of inter- and intramole...
Article
Background/Introduction Positron Emission Tomography (PET), also a standard in cardiovascular imaging, enables semi-quantitative myocardial perfusion evaluation and assessment of atherosclerosis. PET is based on positron-electro annihilation inside a patient's body and in about 40% events it proceeds via formation of positronium. Positronium is an...
Article
Full-text available
In this study, we verified the hypothesis that Raman signature of urinary extracellular vesicles (UEVs) can be used to stratify patients with diabetes at various stages of chronic kidney disease (CKD). Patients with type 2 diabetes diagnosed with different stages of CKD and healthy subjects were enrolled in the study. UEVs were isolated using low-v...
Article
Full-text available
Charged lepton system symmetry under combined charge, parity, and time-reversal transformation (CPT) remains scarcely tested. Despite stringent quantum-electrodynamic limits, discrepancies in predictions for the electron–positron bound state (positronium atom) motivate further investigation, including fundamental symmetry tests. While CPT noninvari...
Article
Full-text available
For this study, we tested and optimized silicon surface functionalization procedures for capturing urinary extracellular vesicles (uEVs). The influence of the silane type (APTES or GOPS) and protein concentration on the efficiency of uEVs binding was investigated. Human lactadherin protein (LACT) was used to capture uEVs. We applied surface charact...
Preprint
Full-text available
Here, positronium imaging is presented to determine cardiac myxoma (CM) extracted from patients undergoing urgent cardiac surgery due to unexpected atrial masses. Positronium is an atom build from an electron and a positron, produced copiously in intra-molecular voids during the PET imaging. CM, the most common cardiac tumor in adults, accounts for...
Preprint
Full-text available
We perform a parametric study of the newly developed time-of-flight (TOF) image reconstruction algorithm, proposed for the real-time imaging in total-body Jagiellonian PET (J-PET) scanners. The asymmetric 3D filtering kernel is applied at each most likely position of electron-positron annihilation, estimated from the emissions of back-to-back $\gam...
Article
Full-text available
The purpose of the presented research is estimation of the performance characteristics of the economic Total-Body Jagiellonian-PET system (TB-J-PET) constructed from plastic scintillators. The characteristics are estimated according to the NEMA NU-2-2018 standards utilizing the GATE package. The simulated detector consists of 24 modules, each built...
Preprint
Full-text available
The purpose of the presented research is estimation of the performance characteristics of the economic Total-Body Jagiellonian-PET system (TB-J-PET) constructed from plastic scintillators. The characteristics are estimated according to the NEMA NU-2-2018 standards utilizing the GATE package. The simulated detector consists of 24 modules, each built...
Article
Full-text available
We perform a parametric study of the newly developed time-of-flight (TOF) image reconstruction algorithm, proposed for the real-time imaging in total-body Jagiellonian PET (J-PET) scanners. The asymmetric 3D filtering kernel is applied at each most likely position of electron-positron annihilation, estimated from the emissions of back-to-back γ-pho...
Article
Full-text available
Protein content of extracellular vesicles (EVs) can modulate different processes during carcinogenesis. Novel proteomic strategies have been applied several times to profile proteins present in exosomes released by urothelial bladder cancer (UBC) cells. However, similar studies have not been conducted so far on another population of EVs, i.e., ecto...
Article
Background: Mild therapeutic hypothermia (MTH) is believed to reduce the effectiveness of antiplatelet drugs. Effective dual-antiplatelet therapy after percutaneous coronary intervention (PCI) is mandatory to avoid acute stent thrombosis (ST). The effectiveness of ticagrelor in MTH-treated out-of-hospital cardiac arrest (OHCA) survivors is still a...
Article
The J-PET tomograph is constructed from plastic scintillator strips arranged axially in concentric cylindrical layers. It enables investigations of positronium decays by measurement of the time, position, polarization and energy deposited by photons in the scintillators, in contrast to studies conducted so far with crystal and semiconductor based d...
Article
Full-text available
Background Melanoma cells release extracellular vesicles (EVs) subpopulations which differ in size, phenotype and molecular content. Melanoma derived EVs play a role in the development and progression of cancer by delivering surface receptors and bioactive (proteins, lipids, nucleic acids) or signaling molecules to target cells. Methods We applied...
Preprint
Full-text available
Charged lepton system symmetry under combined charge, parity, and time-reversal transformation (CPT) remains scarcely tested. Despite stringent quantum-electrodynamic limits, discrepancies in predictions for the electron–positron bound state (positronium atom) motivate further investigation, including fundamental symmetry tests. While CPT noninvari...
Article
Full-text available
Microvesicles (MVs) are found in several types of body fluids and are promising disease biomarkers and therapeutic targets. This study aimed to develop a novel biofunctionalized surface for binding plasma microvesicles (PMVs) based on a lab-on-a-chip (LOC) approach. A new lactadherin (LACT)-functionalized surface was prepared and examined for monit...
Article
Full-text available
Recent years have brought great focus on the development of drug delivery systems based on extracellular vesicles (EVs). Considering the possible applications of EVs as drug carriers, the isolation process is a crucial step. To solve the problems involved in EV isolation, we developed and validated a new EV isolation method-low-vacuum filtration (L...
Preprint
Full-text available
Research conducted in the framework of the J-PET project aims to develop a cost-effective total-body positron emission tomography scanner. As a first step on the way to construct a full-scale J-PET tomograph from long strips of plastic scintillators, a 24-strip prototype was built and tested. The prototype consists of detection modules arranged axi...
Article
Research conducted in the framework of the Jagiellonian-PET (J-PET) project aims to develop a cost-effective total-body positron emission tomography scanner. As a first step on the way to construct a full-scale J-PET tomograph from long strips of plastic scintillators, a 24-strip prototype was built and tested. The prototype consists of detection m...
Preprint
Recent years brought great focus in the field of development of extracellular vesicles (EVs) based drug-delivery systems. Considering possible applications of EVs as a drug carriers the isolation process is a crucial step. To solve problems related with EV isolation, we created and validated a new EVs isolation method – Low Vacuum Filtration (LVF)...
Article
Three-dimensional (3D) spheroids mimic important properties of tumors and may soon become a reasonable substitute for animal models and human tissue, eliminating numerous problems related to in vivo and ex vivo experiments and pre-clinical drug trials. Currently, various imaging methods including X-ray microtomography (micro-CT), exist but their sp...
Article
Full-text available
Total-body PET opens a new diagnostic paradigm with prospects for personalized disease treatment, yet the high cost of the current crystal-based PET technology limits dissemination of total-body PET in hospitals and even in research clinics. The J-PET tomography system is based on axially arranged low-cost plastic scintillator strips. It constitute...
Article
Full-text available
Purpose: In living organisms, the positron-electron annihilation (occurring during the PET imaging) proceeds in about 30% via creation of a metastable ortho-positronium atom. In the tissue, due to the pick-off and conversion processes, over 98% of ortho-positronia annihilate into two 511 keV photons. In this article, we assess the feasibility for...
Preprint
Full-text available
The J-PET tomograph is constructed from plastic scintillator strips arranged axially in concentric cylindrical layers. It enables investigations of positronium decays by measurement of the time, position, polarization and energy deposited by photons in the scintillators, in contrast to studies conducted so far with crystal and semiconductor based d...
Article
Full-text available
Purpose: The time-over-threshold (TOT) technique is being used widely due to itsimplications in developing the multi-channel readouts, mainly when fast signal processing is required. Using the TOT technique, as a measure of energy loss instead of charge integration methods, significantly reduces the signal readout costs by combining the time and e...
Article
Full-text available
Cutaneous melanoma (CM) is an aggressive type of skin cancer for which effective biomarkers are still needed. Recently, the protein content of extracellular vesicles (ectosomes and exosomes) became increasingly investigated in terms of its functional role in CM and as a source of novel biomarkers; however, the data concerning the proteome of CM-der...
Article
Full-text available
Background: Epidemiologic studies suggest that diabetes is associated with an increased risk of cancer. Concurrently, clinical trials have shown that metformin, which is a first-line antidiabetic drug, displays anticancer activity. The underlying mechanisms for these effects are, however, still not well recognized. Methods: Methods based on atom...
Article
Full-text available
In contrast to standard 2D cell cultures, spheroids are three-dimensional (3D) models which can mimic natural conditions of cancer growth and metabolism. Their complex structure can be investigated and analyzed using fluorescence microscopy and micro-tomographic imaging (micro-CT) as a new technique. In this study, we show application of two differ...
Article
Full-text available
Positron Annihilation Lifetime Spectroscopy (PALS) is a technique based on the analysis of the lifetime of positronium emitted from implanted or delivered positronium donors. This technique employs the lifetime and intensity dependence on the structure of analyzed material. Due to this specific features, PALS might be used in further research proto...
Article
Full-text available
The effect of frailty on short and long term results of interventional treatment of coronary heart disease is not well defined. The evaluation of frailty may be helpful in appointment of most suitable treatment option and timing of patient follow-up. The frailty syndrome in daily practice of interventional cardiology ward (FRAPICA) study objective...
Article
Full-text available
The uPAR protein is one of the most important elements in fibrinolysis. uPAR is associated with many biological processes, such as cell invasion, angiogenesis and cell proliferation. Because of its multifunctional character, it is difficult to produce an effective inhibitor of uPA-uPAR interactions. The present paper shows the current state of know...
Article
Full-text available
Introduction Diabetes mellitus (DM) is the most common metabolic disease. A WHO report from 2016 indicates that 422 million people worldwide suffer from DM or hyperglycaemia because of impaired glucose metabolism. Chronic hyperglycaemia leads to micro- and macrovessel damage, which may result in life-threatening complications. The Wnt pathway regul...
Article
Full-text available
Introduction: RANTES regulates leukocyte recruitment to areas affected by the inflammatory process. Microvesicles (MVs) belong to a subpopulation of extracellular vesicles and show proangiogenic potential by transferring bioactive molecules to target cells. Objectives: the aim of this study was to determine the relationship between circulating p...
Preprint
Full-text available
Time-Over-Threshold (TOT) technique is being used widely due to its implications in developing the multi channel readouts mainly when fast signal processing is required. Using TOT technique as a measure of energy loss instead of charge integration methods significantly reduces the signals readout cost by combining the time and energy information. T...
Article
Full-text available
Background and aims: Diabetic foot ulcers (DFUs) are linked to amputations and premature deaths. Negative pressure wound therapy (NPWT) has been used for DFUs. The mechanism of NPWT's action may be associated with its influence on circulating molecules. We assessed NPWT's effect on the plasma levels of angiopoietin-2 (Ang2), a key regulator of ang...