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1

Experimental and numerical analysis of blood flow in roughness impact-R test

Kopernik Magdalena, Kruczek Dawid, Kurtyka Przemysław, Pomorska Małgorzata, Major Roman

Acta of Bioengineering and Biomechanics

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2022

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Vol. 24, no. 3

120--133

EN

The present paper covers simulation of blood flow in a roughness impact-R test model to anticipate the hemodynamic conditions of adhesion of blood elements to the modified surface. It was performed using numerical modelling of this process. The aim of these simulations was to create a surface morphology that stimulates the adhesion of blood elements to the surface of base plate of impact-R test. Methods: The morphology of base plate of impact-R test was developed using a vacuum powder sintering of commercial purity titanium powder (CP-Ti) on Ti6Al7Nb substrate. The finite volume method (FVM) and disperse particle method (DPM) were applied to develop the target model of a roughness impact-R test. The morphology of modified surfaces was documented with digital microscope and SEM (scanning electron microscopy). Results: The impact-R test developed using the two-phase blood model performed on regularly structured base plate resulted in shear stress values higher than the analogous for the model lacking such modification. The most significant reduction in maximum values of shear stress occurred in case of the DPM model and especially in the model with regular structures. Conclusions: The proposed models are very effective in modeling of the analysis of blood flow in roughness impact-R test.

2

Discrete phase model of blood flow in a roughness microchannel simulating the formation of pseudointima

Kopernik Magdalena, Dyrda Karina, Kurtyka Przemysław, Major Roman

Acta of Bioengineering and Biomechanics

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2022

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Vol. 24, no. 1

132--144

EN

The goal of the present study was the development of discrete phase model to simulate the phenomenon of backfilling a morphologically complex surface by red blood cells (RBCs) in a flow microchannel and to anticipate the conditions of forming a pseudointima. The objective of the experimental studies that inspired the development of the simulation was to create a surface that stimulates the formation of the pseudointima layer. Methods: The finite volume method (FVM) and discrete particle method (DPM) were applied to develop the target model. In addition, a mixture model and a roughness model of bottom layer were tested in the present study to show their influence on simulation the phenomenon of backfilling a morphologically complex surface by RBCs in a flow microchannel. Results: Numerical models were developed including: a) FVM models to compare the effect of applying boundary conditions with/without roughness and cubes, as well as the analysis of their influence on blood velocity and shear stress; b) mixture models to compare the effect of applying different boundary conditions and cubes on computed results; c) DPM models to compare the effect of applying and not applying roughness as a boundary condition; d) DPM models with a morphologically complex surface and RBCs collisions to present RBCs concentration, velocity and time distributions during flow in a channel. Conclusions: The analysis carried out for the developed numerical models indicates that DPM model with cubes computes the best results. It also shows the backfilling of a morphologically complex surface of the bottom microchannel with RBCs.

3

Separation of Cells From Plasma by Means of Ultrasonics

Włoch Andrzej, Czyż Henryka, Jasiński Tadeusz

Archives of Acoustics

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2019

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Vol. 44, No. 2

357--363

EN

This paper presents an analysis of use of ultrasonic standing wave in cell separation from bodily fluids based on the example of erythrocyte separation from plasma. It describes movement of red blood cells in plasma under the influence of the acoustic field (whose forces result from interaction of red blood cells with plasma as the vibrating medium) and under the influence of resistance forces in Stokes’ and Oseen’s approximation. The general properties of solutions of the motion equation are given. The solutions for the parameters of the ultrasonic wave and blood cells which are interesting in terms of practical applications in medical diagnostics are discussed. Time constants of the cell transportation to the regions of stable equilibrium in the field of ultrasonic standing wave are estimated. The formulas which determine the time needed to obtain the assumed concentration increase in plasma in nodes and/or anti-nodes of the standing wave are derived.

4

The fractal dimension of red blood cell aggregates in dextran 70 solutions

Bosek M., Szołna-Chodór A., Antonova N., Grzegorzewski B.

Optica Applicata

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2018

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Vol. 48, nr 3

477--488

EN

Fractal dimension of three dimensional red blood cell aggregates were determined by measurement of their size and sedimentation velocity. The sedimentation of the aggregates was investigated with red blood cells suspended in dextran 70 solutions at concentrations from 2 to 5 g/dL, at hematocrit 5% and 10%. The aggregate velocity and size were measured using an image analysis technique. The velocity vs. radius dependence of the aggregates exhibited a scaling behavior. This behavior showed the fractal structure of the aggregates. It is shown that the fractal dimension of the three dimensional red blood cell aggregates depends on the dextran concentration in the suspension. This parameter exhibited a minimum at dextran concentration between 3 and 4 g/dL. Thus the fractal dimensions increased as the aggregation extent decreased. The obtained results show that the sedimentation experiment together with image analysis is a promising technique to determine the fractal dimension of the three dimensional red blood cell aggregates.

5

A short review of blood flow modelling methods: from macro- to microscales

Kaczorowska K., Tesch K.

TASK Quarterly : scientific bulletin of Academic Computer Centre in Gdansk

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2017

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Vol. 21, No 1

5--16

EN

The aim of this paper it to review various scale approaches to the blood flow modelling. Blood motion may be described by three types of mathematical models according to the observed scales or resolutions, namely microscopic, mesoscopic and macroscopic descriptions. The above approaches are discussed together with their advantages and disadvantages. Several results of mesoscopic simulations are presented with particular attention paid to mesoscale semi-continuum models suitable for real-time blood flow visualisation.

6

Biomechanical properties of the thin PVD coatings defined by red blood cells

Trembecka-Wojciga K., Major R., Lackner J. M., Bruckert F., Jasek E., Major B.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2015

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Vol. 63, nr 3

697--705

EN

The measurement of the strength of bonds between biomaterials and cells is a major challenge in biotribology since it allows for the identification of different species in adhesion phenomena. Biomaterials, such as diamond-like carbon (DLC), titanium, and titanium nitride, seem to be good candidates for future blood-contact applications. These materials were deposited as thin films by the hybrid pulsed laser deposition (PLD) technique to examine the influence of such surfaces on cell behavior. The biomaterial examinations were performed in static conditions with red blood cells and then subjected to a dynamical test to observe the cell detachment kinetics. The tests revealed differences in behavior with respect to the applied coating material. The strongest cell-biomaterial interaction was observed for the carbon-based materials compared to the titanium and titanium nitride. Among many tests, a radial flow interaction analysis gives the opportunity to analyze cell adhesion to the applied material with the high accuracy. Analysis of concentrates helped to select materials for further dynamic tests on blood using an aortic flow simulator. In this case, the platelet adhesion to the surface and their degree of activation was analyzed. The quality of the selected coating was tested using a scratch test. The analyses of the microstructure were done using high resolution transmission electron microscopy. The phase composition and the residual stress were analyzed using X-ray diffraction methods.

7

Zastosowanie spektrometrii absorpcji atomowej w analizie pierwiastkowej próbek klinicznych (krwi)

Długaszek M.

Prace Instytutu Elektrotechniki

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2014

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Z. 266

29--37

PL

Spektrometria absorpcji atomowej (AAS) jest instrumentalną metodą analityczną pozwalającą na oznaczanie śladowych ilości pierwiastków w próbkach o różnym charakterze, także klinicznych. Metoda ta należy do optycznych metod spektroskopowych i bada oddziaływanie promieniowania z zakresu UV i VIS na atomy. W metodzie tej wykorzystywane jest zjawisko absorpcji atomowej. W pracy zbadano i opisano korelacje między ilością pierwiastków w surowicy krwi i krwinkach czerwonych. Zawartość pierwiastków oznaczono stosując płomieniową i bezpłomieniową spektrometrię absorpcji atomowej. Analizę korelacji wykonano w odniesieniu do takich pierwiastków, jak wapń (Ca), magnez (Mg), cynk (Zn), miedź (Cu), żelazo (Fe), glin (Al), ołów (Pb), kadm (Cd) i chrom (Cr).

EN

Atomic absorption spectrometry (AAS) is an instrumental analytical method dedicated for the determination of trace amounts of elements in samples of different nature, including clinical trials. It belongs to the optical spectroscopic methods and examines the impact of UV and VIS radiation on atoms. This method utilizes an atomic absorption phenomenon. In the study, correlations between the number of elements in the blood serum and red blood cells are described. The content of elements was determined using the flame and flameless atomic absorption spectrometry. The correlation analysis was performed with respect to such elements as calcium (Ca), magnesium (Mg), zinc (Zn), copper (Cu), iron (Fe), aluminium (Al), lead (Pb), cadmium (Cd), and chromium (Cr).

8

Opposite effects of electroporation of red blood cell membranes under the influence of zinc ions

Kozlova. E., Chernysh A., Moroz V., Sergunova V., Gudkova O., Fedorova M., Kuzovlev A.

Acta of Bioengineering and Biomechanics

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2012

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Vol. 14, no. 1

3-13

EN

The goal of the study was to investigate the effects of zinc ions of various concentrations on the nanostructure of membrane of red blood cells in in vitro experiment. The suspension of red blood cells extracted from whole human blood was used. The calibrated electroporation and the atomic force microscopy (AFM) were used to analyse damage to membrane nanostructure. We studied the haemolysis after the electroporation at different zinc concentrations. A low concentration of zinc (0.15-0.5 mM) increased significantly the rate of haemolysis and reduced the residual level of non-haemolyzed cells. At high concentrations of zinc ions (0.5-10 mM), the rate constant was sharply reduced, at the same time the residual level increased. The relationship between haemoglobin coagulants and the zinc concentration was examined. High concentration of zinc caused haemoglobin aggregation. It was shown by AFM that the membrane nanostructure was essentially changed. It was experimentally established that there existed a special point of zinc concentration C = 0.5 +- 0.1 mM at which the course of the conjugate processes on the membranes of red blood cells was changed.

9

Assessment of tissue viability by polarization spectroscopy

Nilsson G., Anderson C., Henricson J., Leahy M., O'Doherty J., Sjöberg F.

Opto-Electronics Review

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2008

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Vol. 16, No. 3

309-313

EN

A new and versatile method for tissue viability imaging based on polarization spectroscopy of blood in superficial tissue structures such as the skin is presented in this paper. Linearly polarized light in the visible wavelength region is partly reflected directly by the skin surface and partly diffusely backscattered from the dermal tissue matrix. Most of the directly reflected light preserves its polarization state while the light returning from the deeper tissue layers is depolarized. By the use of a polarization filter positioned in front of a sensitive CCD-array, the light directly reflected from the tissue surface is blocked, while the depolarized light returning from the deeper tissue layers reaches the detector array. By separating the colour planes of the detected image, spectroscopic information about the amount of red blood cells (RBCs) in the microvascular network of the tissue under investigation can be derived. A theory that utilizes the differences in light absorption of RBCs and bloodless tissue in the red and green wavelength region forms the basis of an algorithm for displaying a colour coded map of the RBC distribution in a tissue. Using a fluid model, a linear relationship (cc. = 0.99) between RBC concentration and the output signal was demonstrated within the physiological range 0-4%. In-vivo evaluation using transepidermal application of acetylcholine by the way of iontophoresis displayed the heterogeneity pattern of the vasodilatation produced by the vasoactive agent. Applications of this novel technology are likely to be found in drug and skin care product development as well as in the assessment of skin irritation and tissue repair processes and even ultimately in a clinic case situation.

10

Photodynamic therapy of virus-contaminated red blood cell concentrates

Ziółkowski P., Bonnett R., Valles M., Piasecki E., Jeleń M., Bronowicz A., Ziółkowska J., Symonowicz K.

Acta Bio-Optica et Informatica Medica. Inżynieria Biomedyczna

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2005

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Vol. 11, nr 3-4

75-77

PL

Terapia fotodynamiczna (PDT) jest obiecującą metodą leczenia nowotworów u ludzi. Ostatnio wiele uwagi poświęcono jej zastosowaniu w niszczeniu drobnoustrojów i dzięki temu sterylizacji krwi lub jej produktów do celów transfuzji. Materiały i metody. Fotouczulacze: pochodne liematoporfiryny (HpD), ftalocyjanina zawierająca gal (BON-6) i mesoketol, pochodna chlorynów. Wirusy: wirus zapalenia pęcherzykowego jamy ustnej (VSV) oraz opryszczki zwykłej (HSV-1). Źródło światła: lampa halogenowa. Rozmazy krwi: po PDT pobierano 5-6 mikrolltrów krwi (z wirusem i fotouczulaczem) i wykonywano standardowe rozmazy. Oceny dokonywało niezależnie dwóch patologów. Kryteria oceny: wielkość i kształt krwinek czerwonych -1, prawidłowe; lekko uszkodzone (0,75) i ciężko uszkodzone - 0,5. Agregacja, hemoliza i zwyrodnienie ziarniste były określane w procentach w stosunku do wszystkich komórek. Poniżej 5% - wynik bardzo dobry, krwinki nadające się do transfuzji, 5-10% - dobry, prawdopodobnie nadają się do transfuzji i powyżej 20% - zły, nie nadające się do zastosowania. Wyniki. Wykazały, że oba nowe fotouczulacze są aktywniejsze w zabijaniu wirusów niż HpD. Ponadto, BON-6 i mesoketol w mniejszym stopniu uszkadzają krwinki czerwone. Wniosek. W odniesieniu do chemicznej struktury fotouczulacza, wydaje się, że pewien stopień amfifllności jest niezbędny do fotoinaktywacji wirusów z grupy okopertowanych.

EN

Photodynamic therapy (PDT) is a promising method of treatment of tumors in human. It Is based on application of certain chemicals called as photosensitlzers. Recently, much interest was directed towards antimicrobial use of PDT and thus, possible sterilization of blood or blood products for transfusion. Materials and methods. Photosensltizers: hematoporphyrin derivative (HpD), hydroxygalllum (III). phthalocyanine tetra-sulphonic acid tetrasodium salt (BON-6) and chlorin derivative, mesocetol (mesok). Viruses: vesicular stomatitis virus (VSV) and herpes simplex virus-1 (HSV-1). Light source: halogen lamps were used to sensitize photosensltizers. Blood smears: after PDT was completed 5-6 I of blood (containing sensitizer and virus) were taken, placed on glass slides In order to make smears. After the routine fixation and staining they were evaluated by two Independent pathologists. Evaluation criteria: size and shape of RBC: normal (1), slightly affected (0.75), strongly affected (0.5); aggregation, hemolysis and granular degeneration In % to the total number of cells: < 5% - excellent and suitable for transfusion, 5-10% - good, possible application for transfusion, 10-20% - poor, not suitable and > 20% - bad. Results. They showed that both new photosensitlzers are more active than HpD in photokilling of viruses. Beside It, BON-6 and mesok showed to be less damaging to RBC. Conclusion. With respect to the photosensitlzer structure, we hope at this moment, that a certain degree of amphiphilic character is required to photoinactivate enveloped viruses.

11

Pomiary płynności i mikrolepkości elementów morfotycznych krwi u osób ze sztuczną zastawką serca

Szyller-Tracz M., Żakowska I., Jóźwik K.

Inżynieria Biomateriałów

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2004

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R. 7, nr 35-36

56-61

PL

Warstwa Nanokrystalicznego Diamentu (NCD) została wykorzystana w przypadku protez/urządzeń mających kontakt z komórkami krwi (np. sztuczne zastawki serca). Warstwy węglowe wykazują dobre właściwości biozgodności oraz hemozgodności. W prezentowanych badaniach użyta została technika spektroskopii elektronowego rezonansu paramagnetycznego (EPR) do pomiarów płynności i lepkości wnętrza elementów morfotycznych, w szczególności erytrocytów. Parametry (opisujące płynność lipidów błonowych) ostały określone na podstawie widm EPR. Zmiany w płynności lipidów błonowych i lepkości wnętrza krwinek czerwonych zostały zbadane przy pomocy spektroskopii EPR przy użyciu znaczników spinowych: trzech kwasów tłuszczowych (kwasów 5-, 12-, 16-doksylostearynowych) oraz Tempaminy. Celem niniejszej pracy było przedstawienie metod pomiaru parametrów krwinek czerwonych oraz opracowanie statystyczne uzyskanych wyników. Prezentowane metody mogą zostać użyte do zbadania oddziaływań warstw NCD z komórkami krwi. Przepływ przez sztuczną zastawkę serca jest związany z występowaniem większych wartości naprężeń ścinających działających na powierzchnię komórek oraz w konsekwencji zmian w strukturze lipidów i białek plazmatycznych. Zmiany w płynności lipidów błonowych krwinek czerwonych (RBC) mogą obniżać ich deformację oraz zwiększać ich agregację, a w konsekwencji mogą prowadzić do zmian właściwości reologicznych krwi ludzkiej.

EN

Nanocrystalline Diamond Coatings (NCD) have been developed for blood cell contacting-implants/devices (e.g. artificial heart valves). Carbon surfaces have good biocompatibility and haemocompatibility. In this study the technique of electron paramagnetic resonance (EPR) spectroscopy was used for measurements of fluidity and internal viscosity of morphotic elements, especially erythrocytes. Parameters (describing the membrane lipid fluidity) were determined using EPR spectra. Changes in the membrane lipid fluidity and internal viscosity of red blood cells were examined by means of EPR spectroscopy using spin labelled: three fatty acids (5-, 12-, 16-doxylstearic acids) and Tempamine. The aim of this study was to present the method of measurements of red blood cells and the statistical post-processing of the obtained results. These methods could be used to examine interactions between a NCD layer and blood cells. The blood flow through an artificial heart valve is connected with high values of the shear stress as acting on cell surfaces and, in consequence, by changes in the structure of membrane of lipids and proteins. Changes in plasma membranes of red blood cells (RBC) can decrease their deformation and increase their aggregation and, in consequence can lead to alterations in the rheological properties of human blood.