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The Changes of Elongation Index of erythrocytes caused by storage of blood at low temperature

Dylong Iwona, Dolibog Paweł, Mularz Tomasz, Młynarski Jacek, Grzegorczyn Sławomir

Polish Journal of Medical Physics and Engineering

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2023

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Vol. 29, Iss. 1

35--41

EN

Introduction: An important parameter characterizing the ability of erythrocytes to deform depending on the blood flow conditions is the Elongation Index (EI), and it is a parameter defined by the shape of the erythrocyte obtained as a diffraction pattern of erythrocytes at different values of shear stresses. Material and methods: EI measurements at different shear stress were performed by Laser-assisted Optical Rotational Cell Analyzer (LORRCA) for erythrocytes derived from Tissue Bank in Katowice. Measurements were performed immediately after receiving them from Tissue Bank and after 2, 9, and 28 days of storage of samples at the temperature of 4°C in solution with the anticoagulant. Results: An increase in the erythrocytes Elongation Index in the first 9 days of storing samples at low temperatures was observed in the entire range of applied shear stresses. This indicates an increase in the elasticity of erythrocytes during short-term storage at 4°C. In turn, on the 28th day of erythrocyte storage, a significant decrease in the Elongation Index for shear stresses greater than 1 Pa was observed, which indicates the stiffening of the erythrocyte membrane structure, reducing their elasticity. The relative decrease in the Elongation Index of erythrocytes stored for 28 days compared to erythrocytes measured at the beginning was similar and slightly greater than 30% for shear stresses greater than 3 Pa. For shear stresses lower than 3 Pa, the relative change in elongation index was smaller than for shear stresses greater than 3 Pa and increased with the increase in shear stress. Conclusions: The elongation index of erythrocytes stored in the anticoagulant solution at 4°C, initially increases in the entire range of applied shear stresses in the first few days from the moment of blood collection and preparation at the Tissue Bank, and then decreases, but on the ninth day of storage the elongation index is still higher than for blood immediately after collection.

2

Theory of Red Blood Cell Oscillations in an Ultrasound Field

Johansen K., Kimmel E., Postema M.

Archives of Acoustics

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2017

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Vol. 42, No. 1

121--126

EN

Manipulating particles in the blood pool with noninvasive methods has been of great interest in therapeutic delivery. Recently, it was demonstrated experimentally that red blood cells can be forced to translate and accumulate in an ultrasound field. This acoustic response of the red blood cells has been attributed to sonophores, gas pockets that are formed under the influence of a sound field in the inner-membrane leaflets of biological cells. In this paper, we propose a simpler model: that of the compressible membrane. We derive the spatio-temporal cell dynamics for a spherically symmetric single cell, whilst regarding the cell bilayer membrane as two monolayer Newtonian viscous liquids, separated by a thin gas void. When applying the newly-derived equations to a red blood cell, it is observed that the void inside the bilayer expands to multiples of its original thickness, even at clinically safe acoustic pressure amplitudes. For causing permanent cell rupture during expansion, however, the acoustic pressure amplitudes needed would have to surpass the inertial cavitation threshold by a factor 10. Given the incompressibility of the inner monolayer, the radial oscillations of a cell are governed by the same set of equations as those of a forced antibubble. Evidently, these equations must hold for liposomes under sonication, as well.

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Detection of Erythrocyte Cells in Microscopy Images

Frejlichowski D.

Przegląd Elektrotechniczny

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2012

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R. 88, nr 10b

264-267

EN

In the paper an algorithm for automatic detection of red blood cells in microscopic images is described and investigated. For this purpose digital microscopic images stained by means of the MGG (May-Grunwald-Giemsa) method are applied. This method consists in three main stages. The first one is composed of the conversion to binary image using the modified histogram thresholding. The second one comprises the localisation and extraction of each separate object. The last stage covers the selection of erythrocytes and the rejection of other cells. The method described in the paper method gave the average efficiency above 83%, which is a promising result considering the specific characteristics of the investigated data as well as the large number of cells within an image.

PL

W artykule przedstawiono i omówiono algorytm przeznaczony do automatycznej detekcji czerwonych krwinek na obrazach mikroskopowych. Do tego celu użyto cyfrowych obrazów mikroskopowych, barwionych metodą MGG (May-Grunwald-Giemsa). Metoda opiera się na trzech głównych etapach. Pierwszy to konwersja do obrazu binarnego przy użyciu zmodyfikowanego progowania histogramowego. Drugi to lokalizacja i ekstrakcja każdego obiektu oddzielnie. Ostatni to selekcja erytrocytów i odrzucenie pozostałych komórek krwi. Opisywana w artykule metoda dała średnią skuteczność przekraczającą 83 %, co jest obiecującym wynikiem, biorąc pod uwagę specyficzne cechy badanych danych oraz dużą liczbę komórek na obrazie.

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Biologiczne aspekty heterofazowej struktury krwi i jej znaczenie w procesie miażdżycowym

Wasilewski J., Kiljański T.

Inżynieria i Aparatura Chemiczna

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2012

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Nr 6

398-399

PL

Krew stanowi układ dwufazowy pośredni między zawiesiną i emulsją. Obecność erytrocytów oraz ich wzajemne oddziaływanie powoduje nadawanie krwi własności nienewtonowskich, determinujących hydrodynamikę i funkcje biologiczne krwi. Heterofazowa struktura krwi ma istotne znaczenie w powstawaniu zmian miażdżycowych, prowadzących do zwężenia tętnic. Tworzą się one w miejscach powstawania przepływów zaburzonych, gdzie krwiopochodne cząsteczki przechodzą do ściany tętnicy inicjując powstawanie złogów.

EN

Blood is a two-phase medium situated between suspension and emulsion. The presence of erythrocytes and their interaction gives blood non-Newtonian properties, which determine the hydrodynamics and biological functions of blood. The two-phase blood structure plays an essential role in the formation of atherosclerotic plaques which leads subsequently to arterial stenosis. Plaques preferentially develops at specific sites with disturbed flow, where the blood-borne particles penetrate the arterial wall initiating plaque formation.

5

The criteria of life and aging from a molecular viewpoint. The role of protein aggregation in the process of aging

Spólnik P., Konieczny L., Piekarska B., Rybarska J., Stopa B., Zemanek G.

Bio-Algorithms and Med-Systems

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2011

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Vol. 7, no. 1

23--30

EN

Biological knowledge is expanding rapidly, delving deep into nature’s mechanisms. However, the essence of life as a molecular process still remains unclear. Organized and independently operating biological systems are commonly thought to be living. Unfortunately, these characteristics are too general and altogether insufficient to accurately delimit the boundaries of life. The problem of the relation of many primitive biological entities to the living world is still open. The properties of self-dependent biological systems clearly derive from their highly organized automatic nature. The comparative analysis of genomes of primitive biological organisms seems to be the most promising approach, which may eventually lead to the understanding of life at the molecular level and its definition. The erythrocyte appears to be of particular interest as a model of a living system that is at a boundary. Its biological origin, automatically controlled metabolism, and programmed death sharply defined in time qualify it as the living structure, even though it is completely deprived of a genetic apparatus. However, its membership among living systems seems to be well-founded. Protein aggregation is one of the common characteristics of aging. It is a consequence of abnormalities of protein structure induced by destructive actions but also by abnormalities of synthesis. Aggregation of membrane proteins probably affects the activity of certain enzymes or transport proteins, which are important as energy providers for aging erythrocytes. After the erythrocyte has passed through the vascular system a given number of times, it is not able to undergo a certain set of indispensable metabolic rearrangements. A living thing is then a form of animated nature which has the features of independence as a result of automation and possesses its own compatible with nature program of action which is time-limited beforehand.

6

The Application of Magnesium Ion Selective Electrode in Clinical Analysis

Malon A., Brockmann Ch., Fijalkowska-Morawska J., Rob P., Maj-Zurawska M.

Polish Journal of Chemistry

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2004

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Vol. 78 / nr 9

1619-1625

EN

The role of magnesium is primarily that of a cofactor in intracellular biochemical reactions, therefore, the concentration of intracellular ionized magnesium is much more physiologically relevant. The determination of the ionized magnesium (iMge) in erythrocytes by ion-selective electrode for routine clinical measurements was first time investigated. Intracellular and extracellular magnesium concentration in critically ill postoperative patients and in dialyzed patients was compared with healthy individuals. Of the investigated parameters, iMge seems to be the best magnesium parameter to observe hypo- or hypermagnesemia for both groups of patients. The correlation that was found between extracellular and intracellular magnesium concentrations can be also used to evaluate the magnesium status.