18 research outputs found
Multimodality imaging of intermediate lesions: Data from fractional flow reserve, optical coherence tomography, near-infrared spectroscopy-intravascular ultrasound
Background: Fractional flow reserve (FFR) assesses a functional impact of the atheroma on the myocardial ischemia, but it does not take into account the morphology of the lesion. Previous optical coherence tomography (OCT), intravascular ultrasound (IVUS) and near-infrared spectroscopy (NIRS) studies presented their potential to detect vulnerable plaques, which is not possible by FFR assessment. With the following study, the intermediate lesions were assessed by FFR, OCT and combined NIRS-IVUS imaging to identify plaque vulnerability.
Methods: Thirteen intermediate lesions were analyzed simultaneously by FFR, OCT and combined NIRS-IVUS imaging.
Results: Two lesions were found to have FFR ≤ 0.80 (0.65 and 0.76). The other 11 lesions had FFR > 0.80 with a mean FFR 0.88 ± 0.049. Two lesions with FFR ≤ 0.80 had plaque burden (PB) > 70% and minimal lumen area (MLA) < 4 mm2, but neither of these 2 lesions were identified as OCT defined thin fibrous cap atheroma (TCFA), or NIRS-IVUS possible TCFA. Among the other 11 lesions with FFR > 0.80, 8 were identified as OCT-defined TCFA, 4 had PB > 70%, 6 had MLA < 4 mm2, 2 had both PB > 70% and MLA < 4 mm2, 3 lesions were identified as NIRS-IVUS possible TCFA, and 4 lesions had lipid core burden index > 400.
Conclusions: The FFR-negative lesions pose traits of vulnerability as assessed simultaneously by IVUS, OCT and NIRS imaging.
In Vitro Photodynamic Therapy with Chlorin e6 Leads to Apoptosis of Human Vascular Smooth Muscle Cells
Percutaneous coronary intervention has become the most common and widely implemented method of heart revascularization. However, the development of restenosis remains the major limitation of this method. Photodynamic therapy (PDT) recently emerged as a new and promising method for the prevention of arterial restenosis. Here the efficacy of chlorin e6 in PDT was investigated in vitro using human vascular smooth muscle cells (TG/HA-VSMCs) as one of the cell types crucial in the development of restenosis. PDT-induced cell death was studied on many levels, including annexin V staining, measurement of the generation reactive oxygen species (ROS) and caspase-3 activity, and assessment of changes in mitochondrial membrane potential and fragmentation of DNA. Photosensitization of TG/HA-VSMCs with a 170 μM of chlorin e6 and subsequent illumination with the light of a 672-nm diode laser (2 J/cm2) resulted in the generation of ROS, a decrease in cell membrane polarization, caspase-3 activation, as well as DNA fragmentation. Interestingly, the latter two apoptotic events could not be observed in photosensitized and illuminated NIH3T3 fibroblasts, suggesting different outcomes of the model of PDT in various types of cells. The results obtained with human VSMCs show that chlorin e6 may be useful in the PDT of aerial restenosis, but its efficacy still needs to be established in an animal model
Strategie radzenia sobie z nieznanym słownictwem podczas czytania stosowane przez uczniów szkoły średniej
Czytanie w języku obcym bardzo często sprawia czytelnikom wiele problemów ze względu na występowanie w tekstach nieznanych im słów. Problem ten jest szczególnie widoczny wśród uczniów, którzy z tego powodu bardzo niechętnie korzystają z obcojęzycznych tekstów. Praca miała na celu identyfikację strategii radzenia sobie z nieznanym słownictwem wśród grupy uczniów szkoły średniej oraz zbadanie wpływu treningu na używanie wyżej wspomnianych strategii podczas czytania. Na potrzeby tej pracy strategie zostały zdefiniowane jako działania ukierunkowane na odkrycie znaczenia poszczególnych słów z wykorzystaniem wiedzy ogólnej i wskazówek ukrytych w tekście. Grupę badanych stanowiło 5 uczniów, którzy wzięli udział w sesji głośnego myślenia. Ich zadaniem było przeczytanie tekstu w j. angielskim i opisanie sposobu radzenia sobie z nieznanymi wyrazami w tekście. Następnie został przeprowadzony trening użycia strategii radzenia sobie z nieznanym słownictwem, w którym wzięło udział 18 uczniów, w tym 5 uczestników sesji głośnego myślenia. Po treningu konieczne było ponowne przeprowadzenie sesji w celu porównania użycia strategii podczas czytania. Analiza zebranych wyników wykazała, że uczniowie stosują różne strategie radzenia sobie z nieznanym słownictwem, wykorzystując nie tylko wskazówki ukryte w kontekście, ale także wiedzę ogólną oraz znajomość języków obcych. Przeprowadzenie treningu znacząco wpłynęło na to w jaki sposób uczniowie radzili sobie z nieznanym słownictwem, o czym świadczy wielokrotne i świadome używanie nieznanych im wcześniej strategii wprowadzonych w ramach treningu podczas drugiej sesji głośnego myślenia. Ponadto zaobserwowano zjawisko łączenia kilku strategii przez uczniów w przypadku, gdy jedna strategia nie gwarantowała powodzenia w odgadnięciu znaczenia danego słowa.Due to the presence of the unknown vocabulary items, reading in a foreign language may pose a problem. However, it seems that applying strategies for dealing with unknown words may be a good solution for it. This particular study is aimed at examining the senior secondary learners’ use of discovery strategies and providing them with a training, which should develop their ability to use the already known strategies and acquaint them with the new ones.The research was based on the data obtained during the two think aloud sessions, which were held before and after the strategy training. The participants of the strategy training were 18 senior secondary school students, out of which 5 were invited to take part in the think aloud sessions. The results of the study showed that before the training the students subconsciously used a lot of strategies. Their habit was to look for the discourse clues and the local context clues. They were also referring to their background knowledge about the world and other languages they knew. After the training, the number of the strategies used during the second think aloud session increased significantly. It was caused by the fact that they began to use a combination of strategies for the particular word meaning construction in order to be sure of the correctness of their guess. What is more, they started to use some new strategies which they had learned during the training. All in all, the training significantly influenced their use of strategies and it seems to be worthy of recommendation for all senior secondary schools
Is it possible to defect unstable atheromatous plaque? New experimental methods tested in catheterisation laboratory
Telemedicine in Cardiology: Modern Technologies to Improve Cardiovascular Patients’ Outcomes—A Narrative Review
The registration of physical signals has long been an important part of cardiological diagnostics. Current technology makes it possible to send large amounts of data to remote locations. Solutions that enable diagnosis and treatment without direct contact with patients are of enormous value, especially during the COVID-19 outbreak, as the elderly require special protection. The most important examples of telemonitoring in cardiology include the use of implanted devices such as pacemakers and defibrillators, as well as wearable sensors and data processing units. The arrythmia detection and monitoring patients with heart failure are the best studied in the clinical setting, although in many instances we still lack clear evidence of benefits of remote approaches vs. standard care. Monitoring for ischemia is less well studied. It is clear however that the economic and organizational gains of telemonitoring for healthcare systems are substantial. Both patients and healthcare professionals have expressed an enormous demand for the further development of such technologies. In addition to these subjects, in this paper we also describe the safety concerns associated with transmitting and storing potentially sensitive personal data
In vitro photodynamic diagnosis of atherosclerotic wall changes with the use of mono-l-aspartyl chlorin e6. A preliminary report
Background: Although several methods for atherosclerosis detection are available, none of them seems to be accurate enough to identify the vulnerable atheromatous plaque. Photodynamic diagnosis (PDD) and therapy (PDT) - a new method evaluated for neoplasm treatment, is a modern approach for detecting and treating atherosclerosis.Aim: To asses in vitro the capability of PDD with the use of chlorin e6 to detect atherosclerotic plaque and the usefulness of this method as a feedback system for photoangioplasty treatment.Methods: 30 specimens of human aorta and 15 specimens of human coronary arteries were examined. The samples were soaked with chlorin e6 and then washed out. The luminescence spectra were then collected. All samples were examined with light microscopy.Results: Tissue fluorescence is seen as green light. We noted a very strong red fluorescence of chlorin e6 originating from lipid-rich plaque. We established a quantitative factor (R) which is the ratio of chlorin e6 red intensity in its 660 nm maximum to the area of green luminescence centred at 515 nm. The highest value of R was reached at the atheromatous samples, followed by calcified and normal ones R2=3.51±0.62, R3=1.63±0.31, and R1=1.51±0.15, respectively. A statistically significant difference was noted between groups two and one, and between groups two and three (R2=3.51±0.62 vs. R3=1.63±0.31,
Production, Mechanical Properties and Biomedical Characterization of ZrTi-Based Bulk Metallic Glasses in Comparison with 316L Stainless Steel and Ti6Al4V Alloy
Microstructure, mechanical properties, corrosion resistance, and biocompatibility were studied for rapidly cooled 3 mm rods of Zr40Ti15Cu10Ni10Be25, Zr50Ti5Cu10Ni10Be25, and Zr40Ti15Cu10Ni5Si5Be25 (at.%) alloys, as well as for the reference 316L stainless steel and Ti-based Ti6Al4V alloy. Microstructure investigations confirm that Zr-based bulk metallic samples exhibit a glassy structure with minor fractions of crystalline phases. The nanoindentation tests carried out for all investigated composite materials allowed us to determine the mechanical parameters of individual phases observed in the samples. The instrumental hardness and elastic to total deformation energy ratio for every single phase observed in the manufactured Zr-based materials are higher than for the reference materials (316L stainless steel and Ti6Al4V alloy). A scratch tester used to determine the wear behavior of manufactured samples and reference materials revealed the effect of microstructure on mechanical parameters such as residual depth, friction force, and coefficient of friction. Electrochemical investigations in simulated body fluid performed up to 120 h show better or comparable corrosion resistance of Zr-based bulk metallic glasses in comparison with 316L stainless steel and Ti6Al4V alloy. The fibroblasts viability studies confirm the good biocompatibility of the produced materials. All obtained results show that fabricated biocompatible Zr-based materials are promising candidates for biomedical implants that require enhanced mechanical properties
Impact of Liposomal Drug Formulations on the RBCs Shape, Transmembrane Potential, and Mechanical Properties
Liposomal technologies are used in order to improve the effectiveness of current therapies or to reduce their negative side effects. However, the liposome–erythrocyte interaction during the intravenous administration of liposomal drug formulations may result in changes within the red blood cells (RBCs). In this study, it was shown that phosphatidylcholine-composed liposomal formulations of Photolon, used as a drug model, significantly influences the transmembrane potential, stiffness, as well as the shape of RBCs. These changes caused decreasing the number of stomatocytes and irregular shapes proportion within the cells exposed to liposomes. Thus, the reduction of anisocytosis was observed. Therefore, some nanodrugs in phosphatidylcholine liposomal formulation may have a beneficial effect on the survival time of erythrocytes
Częstość występowania nadwagi i otyłości u kobiet i mężczyzn w wielu 20-74 lat. Wyniki programu WOBASZ
Antibody CD133 Biofunctionalization of Ammonium Acryloyldimethyltaurate and Vinylpyrrolidone Co-Polymer-Based Coating of the Vascular Implants
Current vascular stents, such as drug eluting stents (DES), have some serious drawbacks, like in stent restenosis and thrombosis. Therefore, other solutions are sought to overcome these post-implantations complications. These include the strategy of biofunctionalization of the stent surface with antibodies that facilitate adhesion of endothelial cells (ECs) or endothelial progenitor cells (EPCs). Rapid re-endothelialization of the surface minimizes the risk of possible complications. In this study, we proposed ammonium acryloyldimethyltaurate/vinylpyrrolidone co-polymer-based surface (AVC), which was mercaptosilanized in order to expose free thiol groups. The presence of free thiol groups allowed for the covalent attachment of CD133 antibodies by disulfide bridges formation between mercaptosilanized surface and cysteine of the protein molecule thiol groups. Various examinations were performed in order to validate the procedure, including attenuated total reflection–Fourier transform infrared spectroscopy (ATR-FTIR) and Fourier transform Raman spectroscopy (FT-Raman), atomic force microscopy (AFM) and scanning electron microscopy (SEM). By means of ATR-FTIR spectroscopy presence of the CD133 antibody within coating was confirmed. In vitro studies proved good biocompatibility for blood cells without induction of hemolytic response. Thus, proposed biofunctionalized CD133 antibody AVC surface has shown sufficient stability for adapting as cardiovascular implant coating and biocompatibility. According to conducted in vitro studies, the modified surface can be further tested for applications in various biological systems