MAGNETOHYDRODYNAMIC EFFECTS ON THE GRANULAR TEMPERATURE OF RED BLOOD CELLS IN MICROVASCULATURE

2017 ◽  
Vol 17 (01) ◽  
pp. 1750003
Author(s):  
MICHALIS XENOS ◽  
ANASTASIOS RAPTIS
Keyword(s):  
Magnetic Field ◽  
Kinetic Theory ◽  
Red Blood Cells ◽  
Blood Cells ◽  
Volume Fraction ◽  
Granular Temperature ◽  
Temperature Profiles ◽  
Migration Process ◽  
Wall Cell ◽  
The Mean

The migration of Red Blood Cells (RBCs) from the wall towards the center of a narrow vessel is the result of the Fahraeus–Lindqvist effect which contemplates the dependence of viscosity and diameter. The kinetic theory explains the formation of the near-wall cell-depleted layer introducing the granular temperature that is defined as the mean square of RBCs fluctuations. The proposed mathematical model elucidates the effect of an externally applied magnetic field on the velocity and granular temperature of RBCs in a microvasculature. The effect of the volume fraction of RBCs on the velocity and granular temperature profiles is also presented and discussed. Based on the insight of the kinetic theory, the application of a stronger static magnetic field probably leads to a restriction of the migration process of RBCs towards the center of the microvessel.

scholarly journals Haemorheology in dilute, semi-dilute and dense suspensions of red blood cells

2019 ◽  
Vol 872 ◽  
pp. 818-848 ◽  
Author(s):  
Naoki Takeishi ◽  
Marco E. Rosti ◽  
Yohsuke Imai ◽  
Shigeo Wada ◽  
Luca Brandt
Keyword(s):  
Red Blood Cells ◽  
Intrinsic Viscosity ◽  
Blood Cells ◽  
Volume Fraction ◽  
Relative Viscosity ◽  
Shear Plane ◽  
Constitutive Law ◽  
Stable Mode ◽  
Volume Fractions ◽  
Wide Range

We present a numerical analysis of the rheology of a suspension of red blood cells (RBCs) in a wall-bounded shear flow. The flow is assumed as almost inertialess. The suspension of RBCs, modelled as biconcave capsules whose membrane follows the Skalak constitutive law, is simulated for a wide range of viscosity ratios between the cytoplasm and plasma,$\unicode[STIX]{x1D706}=0.1$–10, for volume fractions up to$\unicode[STIX]{x1D719}=0.41$and for different capillary numbers ($Ca$). Our numerical results show that an RBC at low$Ca$tends to orient to the shear plane and exhibits so-called rolling motion, a stable mode with higher intrinsic viscosity than the so-called tumbling motion. As$Ca$increases, the mode shifts from the rolling to the swinging motion. Hydrodynamic interactions (higher volume fraction) also allow RBCs to exhibit tumbling or swinging motions resulting in a drop of the intrinsic viscosity for dilute and semi-dilute suspensions. Because of this mode change, conventional ways of modelling the relative viscosity as a polynomial function of$\unicode[STIX]{x1D719}$cannot be simply applied in suspensions of RBCs at low volume fractions. The relative viscosity for high volume fractions, however, can be well described as a function of an effective volume fraction, defined by the volume of spheres of radius equal to the semi-middle axis of a deformed RBC. We find that the relative viscosity successfully collapses on a single nonlinear curve independently of$\unicode[STIX]{x1D706}$except for the case with$Ca\geqslant 0.4$, where the fit works only in the case of low/moderate volume fraction, and fails in the case of a fully dense suspension.

scholarly journals The Quality Assessment of Stored Red Blood Cells Probed Using Atomic-Force Microscopy

2014 ◽  
Vol 2014 ◽  
pp. 1-5 ◽  
Author(s):  
I. M. Lamzin ◽  
R. M. Khayrullin
Keyword(s):  
Red Blood Cells ◽  
Blood Cells ◽  
Morphological Characteristics ◽  
High Increase ◽  
Mean Values ◽  
Force Microscopy ◽  
Atomic Force ◽  
The Mean ◽  
The Moment

At the moment the suitability of stored red blood cells (sRBC) for transfusion is checked by routine methods such as haemoglobin estimation and the level of haemolysis. These methods cannot characterize directly the quality of the membranes of sRBC. The aim of this work is to assess the quality of sRBC based on such criteria as the membrane’s stiffness and the size and the form of sRBC. Materials and Methods. We have investigated 5 series of dry cytosmears of the sRBC which had been kept in blood bank in a period from 1 to 35 days. After AFM imaging, in every specimen, 5 RBC were chosen at random; the diameter, the height, and the stiffness were measured on each of them. Results. The present study shows high increase of the mean values of YM and height of RBC after 35 days of storage and decrease of the mean values of their diameter. Conclusion. Statistically significant high increase of the mean values of YM indicates the decrease of the elasticity of the cells in the course of storing of the RBC. This parameter along with the morphological characteristics can be used as criterion for assessment of applicability of the sRBC for blood transfusion.

Erythroplateletapheresis: A New Strategy in the Global Apheresis Program

1998 ◽  
Vol 21 (6_suppl) ◽  
pp. 17-19
Author(s):  
G. Menichella ◽  
M. Ciarli ◽  
R. Serafini ◽  
L. Pierelli ◽  
M. Vittori ◽  
...  
Keyword(s):  
Blood Cell ◽  
Red Blood Cells ◽  
Plasma Volume ◽  
Blood Cells ◽  
Storage Time ◽  
Blood Donation ◽  
Mean Values ◽  
Packed Red Blood Cells ◽  
New Strategy ◽  
The Mean

Blood donation allowed by cell separators can offer higher performance and higher yield to guarantee better quality and pureness of collected products. New systems for the collection of platelet concentrate (PC) and packed red blood cells (PRBC) are currently available. The aim of our work was to test the possibility of preparing PC routinely from normal apheresis donors in a minimum amount of time while providing a second product. Over a 3-month period we performed 40 procedures using the Hemonetics MCS3P blood cell separator and the Dideco Excel. The mean values of platelet yield were 2.8 x 1011 (range 1.4-4.1) with the MCS3P and 3.49 x 1011 (range 2.9-3.9) with the Excel, in a plasma volume of 240 ml and 215 ml respectively; the PRBC units were added with SAG-Mannitol allowing a storage time of 42 days. Collection times were 71’ and 48’ respectively. Donor tolerance was analogous to phateletapheresis or plasmapheresis.

Catechol O-Methyltransferase in Red Blood Cells of Schizophrenic, Depressed, and Normal Human Subjects

1976 ◽  
Vol 128 (2) ◽  
pp. 184-187 ◽  
Author(s):  
Helen L. White ◽  
Malcolm N. McLeod ◽  
Jonathan R. T. Davidson
Keyword(s):  
Red Blood Cells ◽  
Blood Cells ◽  
Human Subjects ◽  
Normal Subjects ◽  
Enzyme Preparations ◽  
Human Red Blood Cells ◽  
Schizophrenic Patients ◽  
Normal Human ◽  
The Mean ◽  
Isoelectric Ph

SummaryCatechol O-methyltransferase of lysed human red blood cells was assayed under optimal conditions, using saturating concentrations of the substrates, S-adenosyl-L-methionine and 3,4-dihydroxybenzoic acid. The mean enzyme activity found in 24 normal subjects was 29.2 nmol/hr/ml RBC. The mean activity in blood of 33 female unipolar depressives was not significantly different from normal. However, higher enzyme activities were observed in the blood of 11 schizophrenic patients (38.9 nmol/hr/ml RBC). Partially purified enzyme preparations from blood of normal and schizophrenic individuals were indistinguishable with respect to substrate specificities, isoelectric pH values, and ratios of the two O-methylated products. Therefore it is unlikely that any defect in O-methylation which may occur in schizophrenia can be attributed to a change in the intrinsic properties of erythrocyte catechol O-methyltransferase.

A survey of the potassium concentration in the red blood cells of British breeds of sheep

1957 ◽  
Vol 48 (4) ◽  
pp. 433-437 ◽  
Author(s):  
John V. Evans ◽  
M. S. Mounib
Keyword(s):  
Red Blood Cells ◽  
Whole Blood ◽  
Blood Cells ◽  
Potassium Concentration ◽  
High Potassium ◽  
The Mean ◽  
High Level ◽  
Mean Concentration ◽  
Representative Samples

The concentrations of potassium in the whole blood of representative samples of sixteen British breeds of sheep have been studied.The proportion of sheep with a high level of potassium in the whole blood (high potassium or HK type) was found to differ significantly between breeds. It ranged from 0% in the English Leicester to 73% in the Rough Fell.There were significant differences between breeds in the mean concentration of potassium in the whole blood of both the LK and HK sheep.

scholarly journals Biological Pathotyping of Newcastle Disease Viruses in Sudan 2008–2013

2014 ◽  
Vol 2014 ◽  
pp. 1-4 ◽  
Author(s):  
Egbal Sidahmed Abdelrahim Bilal ◽  
Iman Mohammed Elnasri ◽  
Aymen Mohamed Alhassan ◽  
Khalda Abdelaziz Khalifa ◽  
Jedddha Ibrahim Elhag ◽  
...  
Keyword(s):  
Newcastle Disease Virus ◽  
Red Blood Cells ◽  
Disease Virus ◽  
Newcastle Disease ◽  
Blood Cells ◽  
Biological Properties ◽  
Elution Time ◽  
Death Time ◽  
The Mean ◽  
Chicken Erythrocytes

The biological properties and pathogenicity of seven Newcastle disease virus field isolates were studied. These isolates were recovered from different outbreaks in Sudan (5 from chickens and 2 from pigeons) during 2008–2013. Based on intracerebral pathogenicity index, four NDV isolates were characterized as velogenic (their ICPI ranged 2.0–1.6) and three isolates were characterized as mesogenic (ICPI ranged 1.2–1.3). The mean death time for all isolates ranged from 54 to 76.8 hours. The elution time of the viruses from chicken erythrocytes and the ability to haemagglutinate mammalian red blood cells differed considerably in their reactions.

Disaggregation of stacked red blood cells under strong pulse magnetic field

2015 ◽  
Vol 117 (17) ◽  
pp. 17D156 ◽  
Author(s):  
Do-Guwn Hwang ◽  
Hyeji Park ◽  
Woori Kim ◽  
Jinyoung Lee ◽  
Hyun Sook Lee
Keyword(s):  
Magnetic Field ◽  
Red Blood Cells ◽  
Blood Cells ◽  
Pulse Magnetic Field
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