European Journal of Clinical and Experimental Medicine T.15, z. 2 (2017)

URI dla tej Kolekcjihttp://repozytorium.ur.edu.pl/handle/item/3184

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19F MRI As a tool for imaging drug delivery to tissue and individual cells
(Wydawnictwo Uniwersytetu Rzeszowskiego, 2017) Bober, Zuzanna; Aebisher, David; Ożóg, Łukasz; Tabarkiewicz, Jacek; Tutka, Piotr; Bartusik-Aebisher, Dorota
Over the past few decades, magnetic resonance imaging (MRI) has proven to be extremely successful in medical applications. More recently, the biomedical applications of MRI have been gaining more use in the field of clinical pharmacy. In 1977, perfluorocarbon compounds (PFC), which form emulsions that can carry drugs, were analyzed by 19F MRI and emulsified PFC compounds have been investigated as potential blood substitutes since the early 1960s and now a wide variety of PFC compounds are currently available as 19F MRI biomarkers. Molecules with 19F substituents are particularly attractive for use in drug tracking by 19F MRI due to 100% 19F abundance, high 19F MRI sensitivity (0.83 relative to 1H MRI) and an impressively large chemical shift range (400 ppm). Another benefit in the use of 19F MRI is a zero background signal in biological samples due to lack of endogenous fluorine. Therefore, drugs containing fluorine atom have potential for 19F MRI imaging drug delivery to tissue. This article will review recent developments in the use of 19F MRI in imaging drug delivery to tissue and individual cells.
ASL (Arterial Spin Labeling) – historical and current perfusion MR methods
(Wydawnictwo Uniwersytetu Rzeszowskiego, 2017) Guz, Wiesław; Bober, Zuzanna; Ożóg, Łukasz; Truszkiewicz, Adrian; Przypek, Aneta; Aebisher, David; Bartusik-Aebisher, Dorota; Urbanik, Andrzej
Despite continuous scientific and technological advances in MR imaging, MR perfusion methods have not yet been widely deployed for routine clinical diagnostics. This is especially true for ASL (arterial spin labelling) methods used to evaluate cerebral perfusion. This method does not require a contrast agent, as new discoveries about gadolinium accumulation in the cerebellum and brain nucleus appear to be a valuable asset and provide the opportunity to be more widely deployed in clinical practice. The aim of this paper is to present the historical determinants of the development of MR perfusion techniques, the disadvantages and advantages and possible clinical applications and prospects of ASL development. Both historical articles published on MR in the 1990s and current research between 2006-2016 have been reviewed. The authors present in the work the MR perfusion method focusing on issues related to arterial spin labeling (ASL). Historically CASL (continuous ASL) and PCSL (pulsed ASL) techniques have been described and the pseudocontinuous ASL (pseudocontinuous ASL) 3D technique presents its technical and methodological considerations, advantages and disadvantages over previous methods. The methods of test protocol optimization and accompanying artifacts, as well as possible clinical applications and development perspectives, have been described.
Chemiluminescence-driven Dye Excitation for Dark Photodynamic Therapy
(Wydawnictwo Uniwersytetu Rzeszowskiego, 2017) Ożóg, Łukasz; Tabarkiewicz, Jacek; Aebisher, David
Photodynamic therapy is a treatment that uses a combination of light-absorbing photosensitizers and dissolved oxygen to kill cancer. One specific limitation of photodynamic therapy is that the visible light used for photosensitizer excitation has a short tissue penetration depth of several millimeters. This limits the application of photodynamic therapy to surface cancers in the absence of a technique to illuminate deeper tissue. Efforts to extend tissue depth to which photodynamic therapy can be applied have been attempted with use of up-conversion and persistent-luminescent nanoparticles that absorb near infrared light and emit visible light for photosensitizer excitation, yet an initial excitation with an external light source is still required. More recently, systems employing chemiluminescence as an excitation energy source designed to bypass the use of external light have been developed and investigated as potential agents that could overcome the problem of achieving photodynamic therapy in deep tissue. We wish to provide an overview of several systems that have been recently reported that employ both radiative and non-radiative chemiluminescent energy transfer for photosensitizer excitation that have been developed in the hope of achieving “dark” photodynamic therapy. This article reviews several of these important new developments in the design of photodynamic therapeutic systems that utilize chemiluminescence.
Clinical application of advanced neuroimaging techniques – Magnetic Resonance Spectroscopy
(Wydawnictwo Uniwersytetu Rzeszowskiego, 2017) Guz, Wiesław; Bober, Zuzanna; Ożóg, Łukasz; Truszkiewicz, Adrian; Przypek, Aneta; Aebisher, David; Bartusik-Aebisher, Dorota; Urbanik, Andrzej
Continuous scientific research and the increasing saturation of the medical market in Poland implements the possibilities of using advanced MR techniques including MRS in everyday practice. This method, which has so far been used primarily for research purposes, can bring measurable benefits to patients not only in terms of clarifying diagnosis and narrowing differential diagnosis, but also monitoring the course of various diseases and their treatment. Here we present the basic principles of performing and interpreting spectroscopic spectra and possible clinical applications and development prospects of MRS. The literature reviewed both Polish and foreign articles both historically and in the past 10 years. The paper presents methodological issues related to the proper performance of magnetic resonance spectroscopy (MRS) and spectral composition and the role of major metabolites, as well as current clinical applications and directions of MRS development.
Functional MRI – how does it work?
(Wydawnictwo Uniwersytetu Rzeszowskiego, 2017) Truszkiewicz, Adrian; Aebisher, David; Przypek, Aneta; Guz, Wiesław; Bartusik-Aebisher, Dorota
Magnetic Nuclear Resonance (MRI) is a non-invasive tissue imaging method. This technique is based on the influence of a strong magnetic field and electromagnetic wave of strictly defined frequency on the nucleus of elements with non-zero spin. The study describes one of the variants of functional MRI, (fMRI), which has become a key technique in brain imaging. This technique has excellent spatial and temporal resolution and involves a changing signal intensity depending on the degree of oxygenation of the blood. Blood oxygenation levels are known to vary in accordance with neural activity and these differences can be used to detect brain activity. This is due to increased demand for energy and oxygen in the area of increased neural activity. The basis of this imaging is the so-called Blood Oxygenation-Level Dependent (BLOD) effect. The aim of this paper is to present the scope of fMRI as a diagnostic method in neurology and in neurosurgery. This paper presents the principles of fMRI, methods of application, research result development, and suggests areas of possible medical applications. The limitations of fMRI as a clinical tool in medical applications will also be addressed. Studies presented in this paper are based on clinical fMRI experience and a literature review.
Investigation of pharmaceuticals by nuclear magnetic resonance imaging and spectroscopy
(Wydawnictwo Uniwersytetu Rzeszowskiego, 2017) Bober, Zuzanna; Aebisher, David; Tabarkiewicz, Jacek; Guz, Wiesław; Tutka, Piotr; Bartusik-Aebisher, Dorota
Currently, new and easier ways of analyzing pharmaceutical drug forms and drug delivery mechanisms are being sought. Magnetic resonance imaging (MRI) is a non-invasive imaging technique that images drug forms such as tablets, liquids and topicals and drug form behavior in living organisms on both the tissue and cellular scale. The advantages of MRI include noninvasiveness, variable sample capacity and ease of transfer of phantom results to in vitro and in vivo studies. This review concerns the usefulness of clinical MRI that cannot be understated as this technique provides non-invasive and non-destructive insight into the properties of drug delivery systems. The research discussed here concerns the use of magnetic resonance, spectroscopy and chromatography to investigate selected pharmaceuticals and covers work of selecting drugs and antibodies for modification by synthesis for evaluation by MRI. Modifications have been aimed at improving therapeutic efficacy, delivery, and MRI. Modification conditions such as (pH, concentration, temperature, and the influence of other components present in the solutions) will be discussed to understand drug delivery system improvements and the reliability and repeatability of the results obtained. We hope to explore and expand the scope of pharmaceutical imaging with MRI for application in clinical medicine.
Magnetic Resonance Elastography – noninvasive method to assess liver disease
(Wydawnictwo Uniwersytetu Rzeszowskiego, 2017) Ożóg, Łukasz; Aebisher, David; Bober, Zuzanna; Bartusik-Aebisher, Dorota; Guz, Wiesław; Cholewa, Marian
Currently, liver disease is widespread and the awareness of these diseases is low. Early symptoms of liver disease do not necessarily indicate problems with this organ and patients are usually informed of their problems when the stage of the disease is already advanced. Invasive biopsies are the clinical diagnostic method most commonly used in the evaluation of liver disease. A biopsy is associated with a high risk of false results and additional complications. Finding new non-invasive imaging methods has led to the discovery of a new method called Magnetic Resonance Elastography (MRE). This technique allows one to evaluate the mechanical properties of tissues and to distinguish between pathological states. Testing using this technique can be performed on a conventional magnetic resonance system by using few additional components and properly prepared software. Studies have shown that there is a strong correlation between MRE-measured liver stiffness and the degree of fibrosis. MRE is also useful in characterizing liver tumors. Studies show that this technique is highly credible in both health volunteers and patients with liver fibrosis. MRE has tremendous diagnostic potential. The described technique is not currently widely used and has the potential to serve as a safe and accurate alternative in clinical diagnostics in the future.

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Przeglądanie European Journal of Clinical and Experimental Medicine T.15, z. 2 (2017) według Autor "Aebisher, David"