Herbert J Meiselman

University of Southern California, Los Ángeles, California, United States

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Publications (302)790.9 Total impact

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    Robert Elsner · Herbert J. Meiselman · Oguz K. Baskurt

    Full-text · Dataset · Jan 2016
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    Dataset: marine
    Robert Elsner · Herbert J. Meiselman · Oguz K. Baskurt

    Full-text · Dataset · Jan 2016
  • Zhang Zhengwen · Herbert J Meiselman · Björn Neu
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    ABSTRACT: Background: Cell-cell and cell-surface adhesion modulated by water-soluble polymers continues to be of current interest, especially since prior reports have indicated a role for depletion-mediated attractive forces. Objective: To determine the effects of concentration and molecular mass of the neutral polymer dextran (40 kDa to 28 MDa) on the adhesion of human red blood cells (RBC) to coated glass coverslips. Methods: Confocal-reflection interference contrast microscopy (C-IRM), in conjunction with phase contrast imaging, was utilized to measure the adhesion dynamics and contact mechanics of RBC during the initial stages of cell contact with several types of substrates. Results: Adhesion is markedly increased in the presence of dextran with a molecular mass ⩾ 70 kDa. This increased adhesiveness is attributed to reduced surface concentration of the large polymers and hence increased attractive forces due to depletion interaction. The equilibrium deformation of adhering RBC was modeled as a truncated sphere and the calculated adhesion energies were in close agreement with theoretical results. Conclusions: These results clearly demonstrate that polymer depletion can promote RBC adhesion to artificial surfaces and suggest that this phenomenon may play a role in other specific and non-specific cell-cell interactions, such as rouleau formation and RBC-endothelial cell adhesion.
    No preview · Article · Nov 2015 · Biorheology
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    ABSTRACT: Sickle cell disease (SCD) is characterized by sudden onset of painful vaso-occlusive crises (VOC), which occur on top of the underlying chronic blood disorder. The mechanisms that trigger VOC remain elusive, but recent work suggests that autonomic dysfunction may be an important predisposing factor. Heart-rate variability has been employed in previous studies, but the derived indices have provided only limited univariate information about autonomic cardiovascular control in SCD. To circumvent this limitation, a time-varying modeling approach was applied to investigate the functional mechanisms relating blood pressure (BP) and respiration to heart rate and peripheral vascular resistance in healthy controls, untreated SCD subjects and SCD subjects undergoing chronic transfusion therapy. Measurements of respiration, heart rate, continuous noninvasive BP and peripheral vascular resistance were made before, during and after the application of cold face stimulation (CFS), which perturbs both the parasympathetic and sympathetic nervous systems. Cardiac baroreflex sensitivity estimated from the model was found to be impaired in nontransfused SCD subjects, but partially restored in SCD subjects undergoing transfusion therapy. Respiratory-cardiac coupling gain was decreased in SCD and remained unchanged by chronic transfusion. These results are consistent with autonomic dysfunction in the form of impaired parasympathetic control and sympathetic overactivity. As well, CFS led to a significant reduction in vascular resistance baroreflex sensitivity in the nontransfused SCD subjects but not in the other groups. This blunting of the baroreflex control of peripheral vascular resistance during elevated sympathetic drive could be a potential factor contributing to the triggering of VOC in SCD. © 2015 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of the American Physiological Society and The Physiological Society.
    Preview · Article · Jul 2015
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    ABSTRACT: Tricuspid regurgitant (TR) jet velocity and its relationship to pulmonary hypertension has been controversial in sickle cell disease (SCD). Plasma free hemoglobin is elevated in SCD patients and acutely impairs systemic vascular reactivity. We postulated that plasma free hemoglobin would be negatively associated with both systemic and pulmonary endothelial function, assessed by flow mediated dilation (FMD) of the brachial artery and TR jet velocity, respectively. Whole blood viscosity, plasma free hemoglobin, TR jet and FMD were measured in chronically transfused SCD pre and post-transfusion(N=25), in non-transfused SCD(N=26), and in ethnicity-matched control subjects(N=10). We found increased TR jet velocity and decreased FMD in non-transfused SCD patients, compared to the other two groups. TR jet velocity was inversely correlated with FMD. There was a striking non-linear relationship between plasma free hemoglobin and both TR jet velocity and FMD. A single transfusion in the chronically transfused cohort improved FMD. In our patient sample, TR jet velocity and FMD were most strongly associated with plasma free hemoglobin and transfusion status (transfusions being protective), and thus consistent with the hypothesis that intravascular hemolysis and increased endogenous erythropoeisis damage vascular endothelia. Copyright © 2015 American Society of Hematology.
    No preview · Article · Jun 2015 · Blood
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    ABSTRACT: Objective: To test the hypothesis that abnormal hemorheology and chronic low-grade inflammation are more prevalent in Lewis negative individuals, possibly contributing to premature atherosclerosis. Methods and results: We enrolled 223 healthy subjects (154 females, mean age: 64yrs). Conventional risk factors, markers of inflammation and hemorheological profiles were measured; Lewis blood group was determined by serology. Conventional risk factors (age, gender, BMI, blood pressure, lipid profile, smoking habit) did not differ among Lewis phenotypes. However, markers of inflammation (WBC, hs-CRP, ESR) were significantly elevated and rheological parameters (RBC aggregation, plasma viscosity) were abnormal in Lewis negative subjects, especially when compared to the Le(a-b+) group. Conclusions: With a prevalence of 33% in select populations, our data support the hypothesis that Le(a-b-) represents a pro-inflammatory phenotype that may contribute to the elevated cardiovascular risk in this group.
    No preview · Article · Mar 2015 · Atherosclerosis
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    ABSTRACT: The glucose transporter GLUT1 at the blood-brain barrier (BBB) mediates glucose transport into the brain. Alzheimer's disease is characterized by early reductions in glucose transport associated with diminished GLUT1 expression at the BBB. Whether GLUT1 reduction influences disease pathogenesis remains, however, elusive. Here we show that GLUT1 deficiency in mice overexpressing amyloid β-peptide (Aβ) precursor protein leads to early cerebral microvascular degeneration, blood flow reductions and dysregulation and BBB breakdown, and to accelerated amyloid β-peptide (Aβ) pathology, reduced Aβ clearance, diminished neuronal activity, behavioral deficits, and progressive neuronal loss and neurodegeneration that develop after initial cerebrovascular degenerative changes. We also show that GLUT1 deficiency in endothelium, but not in astrocytes, initiates the vascular phenotype as shown by BBB breakdown. Thus, reduced BBB GLUT1 expression worsens Alzheimer's disease cerebrovascular degeneration, neuropathology and cognitive function, suggesting that GLUT1 may represent a therapeutic target for Alzheimer's disease vasculo-neuronal dysfunction and degeneration.
    No preview · Article · Mar 2015 · Nature Neuroscience
  • Samar Rad · Herbert J Meiselman · Björn Neu
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    ABSTRACT: A theoretical framework based on macromolecular depletion has been utilized in order to examine the energetics of red blood cell interactions. Three different glycocalyx structures are considered and cell-cell affinities are calculated by superposition of depletion, steric and electrostatic interactions. The theoretical model predicts a non-monotonic dependence of the interaction energies on polymer size. Further, our results indicate that the glycocalyx segment distribution has a large impact on adhesion energies between cells: a linear segment distribution induces the strongest adhesion between cells followed by pseudo-tail and uniform distributions. Our approach confirms the concept of a depletion mechanism for RBC aggregation, and also provides new insights that may eventually help to understand and quantify cellular factors that control red blood cell interactions in health and disease.
    No preview · Article · Sep 2014 · Colloids and surfaces B: Biointerfaces
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    Michael J Simmonds · Nazli Atac · Oguz K Baskurt · Herbert J Meiselman · Ozlem Yalcin
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    ABSTRACT: Background: Previous studies have demonstrated that red blood cells (RBC) either lyse or at least experience mechanical damage following prolonged exposure to high shear stress (≥100 Pa). Conversely, prolonged shear stress exposure within the physiological range (5-20 Pa, 300 s) was recently reported to improve RBC deformability. This study investigated the relationships between shear stress and RBC deformability to determine the breakpoint between beneficial vs. detrimental exposure to shear stress (i.e., "subhemolytic threshold"). A second aim of the study was to determine whether the frequency of intermittent application of shear stress influenced the subhemolytic threshold. Methods: RBC were exposed to various levels of shear stress (0-100 Pa) in a Couette type shearing system for 300 s. RBC deformability was then immediately measured via ektacytometry. Parallel experiments were conducted at the same shear stresses, except the application time differed while keeping constant the total exposure time: shear stress was applied either for 30 s and repeated 10 times (10×30 s) or applied for 15 s and repeated 20 times (20×15 s). Results: For a range of donors, the subhemolytic threshold with constant shear stress application was between 30-40 Pa. When physiological shear stress was applied in an intermittent manner, more frequent applications tended to improve (i.e., increase) RBC deformability. However, when supra-physiological shear stress was applied, both continuous and intermittent protocols damaged RBC. Changes of RBC mechanical behavior occurred without increases of hemoglobin in the suspending media, thus attesting to the absence of hemolysis. Conclusion: Shear stress has a biphasic effect on the mechanical properties of RBC, with the duration and rate of exposure appearing to have minimal impact on the subhemolytic threshold when compared with the magnitude of applied shear stress.
    Full-text · Article · Jun 2014 · Biorheology
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    Michael J Simmonds · Nazli Atac · Oguz K Baskurt · Herbert J Meiselman · Ozlem Yalcin
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    ABSTRACT: BACKGROUND: Previous studies have demonstrated that red blood cells (RBC) either lyse or at least experience mechanical damage following prolonged exposure to high shear stress (≥100 Pa). Conversely, prolonged shear stress exposure within the physiological range (5–20 Pa, 300 s) was recently reported to improve RBC deformability. This study investigated the relationships between shear stress and RBC deformability to determine the breakpoint between beneficial vs. detrimental exposure to shear stress (i.e., “subhemolytic threshold”). A second aim of the study was to determine whether the frequency of intermittent application of shear stress influenced the subhemolytic threshold. METHODS: RBC were exposed to various levels of shear stress (0–100 Pa) in a Couette type shearing system for 300 s. RBC deformability was then immediately measured via ektacytometry. Parallel experiments were conducted at the same shear stresses, except the application time differed while keeping constant the total exposure time: shear stress was applied either for 30 s and repeated 10 times (10×30 s) or applied for 15 s and repeated 20 times (20×15 s). RESULTS: For a range of donors, the subhemolytic threshold with constant shear stress application was between 30–40 Pa. When physiological shear stress was applied in an intermittent manner, more frequent applications tended to improve (i.e., increase) RBC deformability. However, when supra-physiological shear stress was applied, both continuous and intermittent protocols damaged RBC. Changes of RBC mechanical behavior occurred without increases of hemoglobin in the suspending media, thus attesting to the absence of hemolysis. CONCLUSION: Shear stress has a biphasic effect on the mechanical properties of RBC, with the duration and rate of exposure appearing to have minimal impact on the subhemolytic threshold when compared with the magnitude of applied shear stress.
    Full-text · Article · Jun 2014 · Biorheology
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    ABSTRACT: Sickle cell disease (SCD) is characterized by decreased erythrocyte deformability, microvessel occlusion, and severe painful infarctions of different organs. Ektacytometry of SCD red blood cells (RBC) is made difficult by the presence of rigid, poorly-deformable irreversibly sickled cells (ISC) that do not align with the fluid shear field and distort the elliptical diffraction pattern seen with normal RBC. In operation, the computer software fits an outline to the diffraction pattern, then reports an elongation index (EI) at each shear stress based on the length and width of the fitted ellipse: EI=(length-width)/(length+width). Using a commercial ektacytometer (LORCA, Mechatronics Instruments, Netherlands) we have approached the problem of ellipse fitting in two ways: (1) altering the height of the diffraction image on a computer monitor using an aperture within the camera lens; (2) altering the light intensity level (gray level) used by the software to fit the image to an elliptical shape. Neither of these methods affected deformability results (elongation index-shear stress relations) for normal RBC but did markedly affect results for SCD erythrocytes: (1) decreasing image height by 15% and 30% increased EI at moderate to high stresses; (2) progressively increasing the light level increased EI over a wide range of stresses. Fitting data obtained at different image heights using the Lineweaver-Burke routine yielded percentage ISC results in good agreement with microscopic cell counting. We suggest that these two relatively simple approaches allow minimizing artifacts due to the presence of rigid discs or ISC and also suggest the need for additional studies to evaluate the physiological relevance of deformability data obtained via these methods.
    No preview · Article · Jun 2014 · Biorheology
  • Björn Neu · Herbert J Meiselman
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    ABSTRACT: If a surface is in contact with a solution containing macromolecules or proteins, and the loss of configurational entropy of these molecules at the surface is not balanced by adsorption energy, a polymer-poor layer will develop near the surface. If two such layers overlap, an attractive force develops due to the osmotic pressure difference between these depletion zones and the bulk phase. Recent studies have shown that depletion interaction plays a major role in red blood cell (RBC) aggregation and hence it is a major determinate of blood flow stability; depletion interaction also markedly affects RBC adhesion to vascular endothelial cells. Understanding and quantitating factors that regulate depletion in vivo are thus of importance, yet made difficult since only very small changes of the cell surface (e.g., glycocalyx thickness) such as seen during RBC aging can lead to massive changes of depletion interaction and hence cell-cell adhesion. It is suggested that insight into the in vivo relevance of depletion mechanisms may lead to an improved understanding of how and why blood flow is altered in many diseases, and may also provide new biomarkers (e.g., surface properties) that will aid in the development of novel or improved diagnostic and therapeutic tools.
    No preview · Article · May 2014 · Biorheology
  • Pinar Ulker · Filiz Gunduz · Herbert J. Meiselman · Oguz K. Baskurt
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    ABSTRACT: Red blood cells (RBC) possess a functional nitric oxide synthase (NOS) enzyme located in the cell membrane and cytoplasm. It has previously been observed that shear stress acting on RBC activates NOS and causes enhanced NO export. The aim of the present study was to investigate the physiological importance (e. g., in local blood flow regulation) of RBC-derived NO stimulated by application of shear stress. Blood samples and arterial vessel segments were obtained from Wistar rats; RBC suspensions were adjusted to a hematocrit of 0.1 l/l using Krebs solution. In order to apply shear stress to the RBC suspensions they were continuously flowed through a small-bore glass tube for 20 minutes at a wall shear stress of 2 Pa. The RBC suspensions were then perfused through endothelium denuded small mesenteric arteries having a diameter of similar to 300 mu m under both high oxygen (PO2 similar to 130 mmHg) and hypoxic conditions. Perfusion of vessel segments with sheared RBC suspensions caused a significant dilation response under hypoxic conditions but not at high oxygen levels. Incubation of RBC suspensions with the non-specific NOS inhibitor L-NAME (10(-3) M) prior to shear stress application abolished this dilation response. Our results indicate that NO released from RBC due to shear stress activation of NOS results in vasodilation of vessel segments under hypoxic conditions, and strongly suggest that NO originating from RBC may have a functional role in local blood flow regulation.
    No preview · Article · Oct 2013 · Clinical hemorheology and microcirculation
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    Yang Yang · Stephanie Koo · Li Tze Heng · Herbert J Meiselman · Björn Neu
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    ABSTRACT: Abnormal adhesion of red blood cells (RBCs) to vascular endothelium is often associated with reduced levels of sialic acid on RBC membranes and with elevated levels of pro-adhesive plasma proteins. However, the synergistic effects of these two factors on the adhesion are not clear. In this work, we tested the hypothesis that macromolecular depletion interaction originating from non-adsorbing macromolecules can promote the adhesion of RBC with reduced sialic acid content to the endothelium. RBCs are treated with neuraminidase to specifically remove sialic acids from their surface followed by the evaluation of their deformability, zeta potential and membrane proteins. The adhesion of these enzyme-treated RBCs to cultured human umbilical vein endothelial cells (ECs) is studied in the presence of 70 or 500 kDa dextran with a flow chamber assay. Our results demonstrate that removal of sialic acids from RBC surface can induce erythrocyte adhesion to endothelial cells and that such adhesion is significantly enhanced in the presence of high molecular weight dextran. The adhesion-promoting effect of dextran exhibits a strong dependence on dextran concentration and molecular mass, and it is concluded to originate from macromolecular depletion interaction. These results suggest that elevated levels of non-adsorbing macromolecules in plasma might play a significant role in promoting endothelial adhesion of erythrocytes with reduced sialic acids. Our findings should therefore be of great value in understanding abnormal RBC-EC interactions in pathophysiological conditions (e.g., sickle cell disease and diabetes) and after blood transfusions.
    Full-text · Article · Sep 2013 · Biochimica et Biophysica Acta
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    ABSTRACT: The role of membrane fluidity in determining red blood cell (RBC) deformability has been suggested by a number of studies. The present investigation evaluated alterations of RBC membrane fluidity, deformability and stability in the presence of four linear alcohols (methanol, ethanol, propanol and butanol) using ektacytometry and electron paramagnetic resonance (EPR) spectroscopy. All alcohols had a biphasic effect on deformability such that it increased then decreased with increasing concentration; the critical concentration for reversal was an inverse function of molecular size. EPR results showed biphasic changes of near-surface fluidity (i.e., increase then decrease) and a decreased fluidity of the lipid core; rank order of effectiveness was butanol > propanol > ethanol > methanol, with a significant correlation between near-surface fluidity and deformability (r = 0.697; p<0.01). The presence of alcohol enhanced the impairment of RBC deformability caused by subjecting cells to 100 Pa shear stress for 300 s, with significant differences from control being observed at higher concentrations of all four alcohols. The level of hemolysis was dependent on molecular size and concentration, whereas echinocytic shape transformation (i.e., biconcave disc to crenated morphology) was observed only for ethanol and propanol. These results are in accordance with available data obtained on model membranes. They document the presence of mechanical links between RBC deformability and near-surface membrane fluidity, chain length-dependence of the ability of alcohols to alter RBC mechanical behavior, and the biphasic response of RBC deformability and near-surface membrane fluidity to increasing alcohol concentrations.
    Full-text · Article · Sep 2013 · PLoS ONE
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    Michael J Simmonds · Herbert J Meiselman · Oguz K Baskurt
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    ABSTRACT: The flow properties of blood play significant roles in tissue perfusion by contributing to hydrodynamic resistance in blood vessels. These properties are influenced by pathophysiological processes, thereby increasing the clinical relevance of blood rheology information. There is well-established clinical evidence for impaired blood fluidity in humans of advanced age, including enhanced plasma and whole blood viscosity, impaired red blood cell (RBC) deformability and enhanced RBC aggregation. Increased plasma fibrinogen concentration is a common finding in many studies owing to the pro-inflammatory condition of aged individuals; this finding of increased fibrinogen concentration explains the higher plasma viscosity and RBC aggregation in elderly subjects. Enhanced oxidant stress in advanced age is also known to contribute to altered blood fluidity, with RBC deformability being an important determinant of blood viscosity. Several studies have shown that physical activity may improve the hemorheological picture in elderly subjects, yet well-designed observational and mechanistic studies are required to determine the specific effects of regular exercise on hemorheological parameters in healthy and older individuals.
    Full-text · Article · Sep 2013 · Journal of Geriatric Cardiology
  • Ece Meram · Bahar D Yilmaz · Ceren Bas · Nazlı Atac · O Yalcin · Herbert J Meiselman · Oguz K Baskurt
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    ABSTRACT: Classically, it is known that red blood cell (RBC) deformability is determined by the geometric and material properties of these cells. Experimental evidence accumulated during the last decade has introduced the concept of active regulation of RBC deformability. This regulation is mainly related to altered associations between membrane skeletal proteins and integral proteins, with the latter serving to anchor the skeleton to the lipid matrix. It has been hypothesized that shear stress induces alterations of RBC deformability: the current study investigated the dynamics of the transient improvement in deformability induced by shear stress at physiologically-relevant levels. RBC were exposed to various levels of shear stress (SS) in a Couette type shearing system that is part of an ektacytometer, thus permitting the changes in RBC deformability during the application of SS to be monitored. Initial studies showed that there is an increase in deformability of the RBC subjected to SS in the range of 5-20 Pa, with kinetics characterized by time constants of a few seconds. Such improvement in deformability, expressed by an elongation index (EI), was faster with higher levels of SS and hence yielded shorter time constants: absolute values of EI increased by 3-8% of the starting level. Upon the removal of the shear stress, this response by RBC was reversible with a slower time course compared to the increase in EI during application of SS. Increased calcium concentration in the RBC suspending medium prevented the improvement of deformability. It is suggested that the improvement of RBC deformability by shear forces may have significant effects on blood flow dynamics, at least in tissues supplied by blood vessels with impaired vasomotor reserve, and may therefore serve as a compensating mechanism for the maintenance of adequate microcirculatory perfusion.
    No preview · Article · Jul 2013 · Biorheology
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    ABSTRACT: Autologous hematopoietic stem cell gene therapy is an approach to treating sickle cell disease (SCD) patients that may result in lower morbidity than allogeneic transplantation. We examined the potential of a lentiviral vector (LV) (CCL-βAS3-FB) encoding a human hemoglobin (HBB) gene engineered to impede sickle hemoglobin polymerization (HBBAS3) to transduce human BM CD34+ cells from SCD donors and prevent sickling of red blood cells produced by in vitro differentiation. The CCL-βAS3-FB LV transduced BM CD34+ cells from either healthy or SCD donors at similar levels, based on quantitative PCR and colony-forming unit progenitor analysis. Consistent expression of HBBAS3 mRNA and HbAS3 protein compromised a fourth of the total β-globin-like transcripts and hemoglobin (Hb) tetramers. Upon deoxygenation, a lower percentage of HBBAS3-transduced red blood cells exhibited sickling compared with mock-transduced cells from sickle donors. Transduced BM CD34+ cells were transplanted into immunodeficient mice, and the human cells recovered after 2-3 months were cultured for erythroid differentiation, which showed levels of HBBAS3 mRNA similar to those seen in the CD34+ cells that were directly differentiated in vitro. These results demonstrate that the CCL-βAS3-FB LV is capable of efficient transfer and consistent expression of an effective anti-sickling β-globin gene in human SCD BM CD34+ progenitor cells, improving physiologic parameters of the resulting red blood cells.
    Full-text · Article · Jul 2013 · The Journal of clinical investigation
  • Oguz K Baskurt · Herbert J Meiselman
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    ABSTRACT: Red blood cells (RBC) are exposed to various levels of shear stress (SS) during their flow in the circulatory system, yet no significant damage occurs if their mechanical stability is not impaired. Alternatively, normal RBC may be damaged during flow in non-physiological environments and under extreme SS (e.g., extracorporeal circulation, ventricular assist devices). The shear-induced damage may result in hemolysis or altered mechanical properties of RBC that, in turn, reduces the ability of RBC to withstand further damage by SS. An ektacytometer employing a Couette shearing system was used to apply 100 Pa constant level of SS for 300 seconds as a model of sub-hemolytic mechanical stress. The degree of cellular damage during and after the application was assessed by diffraction pattern analysis. The area of the diffraction pattern was found to correlate with the number of RBC in the sheared suspension. Monitoring the ellipse area during the application of gradually increasing SS provides the concentration of the remaining intact RBC, therefore can be used to estimate the hemolytic threshold as a measure of RBC mechanical stability. Hemolytic threshold determined after the mechanical stress application was found to be ~150 Pa, while it was ~250 Pa in the same samples before the SS application. Additionally, SS-elongation index curves recorded before and after the application of the sub-hemolytic SS significantly differed from each other, indicating the impairment in deformability following the mechanical stress. The Couette type ektacytometer can be used as a tool to assess the sub-hemolytic damage to RBC in testing the biomedical equipment.
    No preview · Article · Feb 2013 · Clinical hemorheology and microcirculation
  • A Toth · J Papp · M Rabai · P Kenyeres · Zs Marton · G Kesmarky · I Juricskay · H J Meiselman · K Toth
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    ABSTRACT: Cardiovascular diseases (CVD) are the most frequent cause of death throughout the world. The coronary vessel system is a special part of the circulation since there is a continuous change in blood flow, perfusion pressure and shear rate during each cardiac cycle. It is also the place of the narrowest capillaries in the human body, therefore the role of rheological alterations may be of greater importance than in the other parts of the circulatory system. During the past decades, our group has investigated hemorheological parameters (HP) in over 1,000 patients diagnosed with various forms of ischemic heart disease (IHD). In one prospective study, we measured the HP of patients with acute coronary syndrome (ACS). On admission, all examined variables were significantly worse than those of control subjects. During the hospital phase, some of the HP showed further deterioration, and HP remained in the pathologic range during the follow-up period. In another study, we showed that HP are in close correlation with the severity of coronary artery disease. In patients treated with percutaneous coronary intervention, changes in HP were very similar to those observed in subjects with ACS. In a recent study, we analyzed HP in patients undergoing CABG surgery. Our data suggest a hemorheological advantage of off-pump surgery. In another study low Hct/WBV ratio can be regarded as a risk factor of cardiac death in IHD. Our data indicate that rheological parameters are significantly altered in patients with IHD: the extent of the alterations is in excellent correlation with the clinical severity of the disease. Our findings prove that HP play a critical role in the pathogenesis of myocardial ischemia. In recent in vitro and in vivo studies we have investigated the effects of red wine on hemorheological parameters. Our results show that moderate red wine consumption has beneficial effects on hemorheological parameters which may contribute to the French paradox.
    No preview · Article · Feb 2013 · Clinical hemorheology and microcirculation

Publication Stats

7k Citations
790.90 Total Impact Points

Institutions

  • 1983-2015
    • University of Southern California
      • • Keck School of Medicine
      • • Department of Physiology and Biophysics
      • • Department of Medicine
      Los Ángeles, California, United States
  • 1978-2015
    • University of California, Los Angeles
      • Department of Medicine
      Los Ángeles, California, United States
  • 1981-2014
    • Keck School of Medicine USC
      Los Ángeles, California, United States
  • 1996-2012
    • Children's Hospital Los Angeles
      • • Division of Cardiology
      • • Division of Hematology-Oncology
      Los Angeles, California, United States
  • 2011
    • Koc University
      • School of Medicine
      İstanbul, Istanbul, Turkey
  • 2009
    • University of Debrecen
      • Department of Operative Techniques and Surgical Research
      Debreczyn, Hajdú-Bihar, Hungary
  • 2001-2009
    • Akdeniz University
      • • Faculty of Medicine
      • • Department of Physiology
      Antalya, Antalya, Turkey
    • Humboldt-Universität zu Berlin
      • Department of Biology
      Berlín, Berlin, Germany
  • 2007
    • Nanyang Technological University
      • School of Chemical and Biomedical Engineering
      Tumasik, Singapore
  • 2006
    • University of Alaska Fairbanks
      • Institute of Marine Science
      Fairbanks, Alaska, United States
  • 2000-2004
    • Ben-Gurion University of the Negev
      • Department of Chemistry
      Be'er Sheva`, Southern District, Israel
  • 2002
    • Yaroslavl State Pedagogical University
      Jaroslawl, Jaroslavl, Russia
  • 2000-2002
    • Jules Stein Eye Institute
      Maryland, United States
  • 1992-1997
    • Umeå University
      Umeå, Västerbotten, Sweden
  • 1990-1994
    • Universität Heidelberg
      • Department of Neonatology
      Heidelburg, Baden-Württemberg, Germany
    • Long Beach Memorial Medical Center
      Long Beach, California, United States
  • 1993
    • Helsinki University Central Hospital
      Helsinki, Southern Finland Province, Finland
  • 1991
    • University of Birmingham
      Birmingham, England, United Kingdom