Science.gov

Sample records for nonleukoreduced red blood

  1. Natural antioxidants improve red blood cell "survival" in non-leukoreduced blood samples.

    PubMed

    Kucherenko, Yuliya V; Bernhardt, Ingolf

    2015-01-01

    Blood collected in an anticoagulant can be kept refrigerated in an unmodified state within 5 - 6 weeks. Oxidative damage is considered to be a one of the major factors contributing to the development of storage lesions. Lipid and membrane proteins oxidation results in changes in cation gradients that affect the cell survival. In the present study we used the natural antioxidants and ion channels blockers (L-carnosine, spermine, phloretin and their mixtures) to prolong "survival" of red blood cells (RBCs), measured as the lack of PS exposure and cell hemolysis, in the Alsever's preservative solution upon hypothermic storage. We show that the mixture of carnosine (20 mM), spermine (20 µM) and phloretin (100 µM) effectively blunted phosphatidylserine (PS) exposure, Ca(2+) accumulation and RBCs hemolysis in non-leukoreduced low (∼ 2%) hematocrit samples after 36 days of storage as well as after 1 day of post-storage incubation of the stored cells in physiological saline solution. In addition, a slight but significant decrease in PS exposure was observed in non-leukoreduced high (∼ 20%) hematocrit samples after 36 days of storage with the mixture of substances. We conclude that the use of the mixture of natural antioxidants (carnosine, spermine, and phloretin) as an additive to blood preservative solution provides better RBCs storage and "survival". © 2015 S. Karger AG, Basel.

  2. Induction of platelet white blood cell (WBC) aggregate formation by platelets and WBCs in red blood cell units.

    PubMed

    Keating, Friederike K; Fung, Mark K; Schneider, David J

    2008-06-01

    Transfusion of red blood cell (RBC) preparations is independently associated with adverse clinical outcomes in patients with acute cardiovascular disease. This study was designed to define mechanisms potentially contributing. The presence of platelets (PLTs), activated PLTs (PLTs expressing P-selectin), PLT-monocyte aggregates (PMAs), and PLT-neutrophil aggregates (PNAs) was determined in vitro with the use of flow cytometry in whole blood from healthy volunteers, in RBCs, and in whole blood after adding aliquots of RBCs. Both prestorage leukoreduced and nonleukoreduced RBCs were analyzed. Nonleukoreduced RBCs were subfractionated with the use of centrifugation and filtration to obtain a RBC-free and a cell-free fraction. Formation of PMAs and PNAs was determined in whole blood after the addition of aliquots of these subfractions. Nonleukoreduced RBCs contained 50 +/- 18 percent of the PLTs found in whole blood from healthy volunteers, and 43 +/- 16 percent of the PLTs were activated. Leukoreduced RBCs contained few PLTs (0.2 +/- 0.1% of volunteer blood). The majority (>60%) of white blood cells (WBCs) in nonleukoreduced RBCs were associated with PLTs. The formation of PMAs and PNAs in whole blood was increased approximately fivefold after addition of nonleukoreduced-RBCs (p < 0.0001) and by less than twofold with leukoreduced RBCs (p = 0.01). Addition of the essentially cell-free fraction of nonleukoreduced RBCs did not increase the formation of PNA or PMA in whole blood significantly. RBC preparations, particularly nonleukoreduced RBCs, contain activated PLTs and PLT-WBC aggregates and induce formation of PLT-WBC aggregates. This may be one mechanism contributing to adverse outcomes linked to transfusions in patients with cardiovascular disease.

  3. Red blood cell production

    MedlinePlus

    ... to one part of the body or another. Red blood cells are an important element of blood. Their job ... is carried to and eliminated by the lungs. Red blood cells are formed in the red bone marrow of ...

  4. Routine use of a rapid test to detect bacteria at the time of issue for nonleukoreduced, whole blood-derived platelets.

    PubMed

    Harm, Sarah K; Delaney, Meghan; Charapata, Michael; Aubuchon, James P; Triulzi, Darrell J; Yazer, Mark H

    2013-04-01

    The Pan Genera detection (PGD) test is used to screen platelet (PLT) products for bacterial contamination. We report the experience of using the PGD test on whole blood-derived PLTs (WBPs) at two large centralized transfusion services (CTS). Records of PGD test results were retrospectively reviewed. The PGD test was performed on individual WBP units or pools of WBPs ranging in size from 2 to 6 units at the time of issue. Bacterial culture was performed on PLT products with positive PGD tests, and at one CTS, the available cocomponents. A total of 70,561 WBP pools were screened with the PGD test. There were seven true-positive PGD tests and 242 false-positive tests (positive predictive value of PGD test, 2.81%). The overall contamination rate was 99 per 10(6) WBP pools (1:10,080; 95% confidence interval [CI], 40-204), and the false-positive rate was 3430 per 10(6) WBP pools (1:292; 95% CI, 3011-3890). All seven bacterial isolates were Gram positive. The median age of the individual WBP units in the seven contaminated pools was 5 days (range, 3-5 days) compared to 4 days (range, 1-5 days) in the false-positive pools (p=0.0012). The same bacteria isolated from a positive PLT pool also grew in one red blood cell cocomponent. After testing more than 70,000 WBP pools at two large CTSs, the rate of contaminated WBP pools detected by the PGD test was 99 per 10(6) pools (1:10,080). © 2012 American Association of Blood Banks.

  5. Red blood cell alloimmunization among sickle cell Kuwaiti Arab patients who received red blood cell transfusion.

    PubMed

    Ameen, Reem; Al Shemmari, Salem; Al-Bashir, Abdulaziz

    2009-08-01

    Sickle cell disease (SCD) is common in the Arabian Gulf region. Most cases require a red blood cell (RBC) transfusion, increasing the potential for RBC alloantibody development. The incidence of RBC alloimmunization among Kuwaiti Arab SCD patients is not yet known. This study retrospectively assessed the effect of using two different matching protocols on the incidence of alloimmunization among multiply transfused Kuwaiti Arab SCD patients. A total of 233 Kuwaiti Arab SCD patients were divided into two groups: Group 1 (n = 110) received RBC transfusion through standard ABO- and D-matched nonleukoreduced blood; Group 2 (n = 123) received RBCs matched for ABO, Rh, and K1 poststorage-leukoreduced blood. Multivariate analysis was performed on the factors associated with RBC alloimmunization and antibody specificity. Sixty-five percent of patients in Group 1 developed clinically significant RBC alloantibody with an increased prevalence in females; in patients in Group 2, 23.6% developed RBC alloantibodies (p = 0.01). In Group 1, 72 patients (65.5%) had alloantibodies directed against Rh and Kell systems (p = 0.01). Multivariate analysis further confirmed the results, showing that blood transfusion type and sex have significant effects on the rate of alloimmunizations. This study confirms the importance of selecting RBCs matched for Rh and Kell to reduce the risk of alloimmunizations among Kuwaiti Arab SCD patients.

  6. High Red Blood Cell Count

    MedlinePlus

    Symptoms High red blood cell count By Mayo Clinic Staff A high red blood cell count is an increase in oxygen-carrying cells in your bloodstream. Red blood cells transport oxygen from your lungs to tissues throughout ...

  7. Red Blood Cell Supernatant Potentiates LPS-Induced Proinflammatory Cytokine Response From Peripheral Blood Mononuclear Cells

    PubMed Central

    Nydam, Trevor L.; Clarke, Jason H.; Banerjee, Anirban; Silliman, Christopher C.; McCarter, Martin D.

    2009-01-01

    Allogeneic blood transfusion has an immunomodulatory capacity on its recipients through accumulation of immunologically active substances with blood storage, and prestorage leukoreduction reduces many of these mediators. We investigated lipopolysaccharide (LPS)-induced cytokine response of peripheral blood mononuclear cells (PBMCs) exposed to packed red blood cell (PRBC) supernatants from leukoreduced (LR) or non-leukoreduced (NLR) units with variable duration of storage. PRBC units were collected with or without leukoreduction on Day 0 before routine storage. The plasma fraction (supernatant) was isolated from LR and NLR units after 1 day (D1) or 42 days (D42) of storage and exposed to PBMCs versus control media for 24 h, then with LPS for an additional 24 h. Cell supernatants were analyzed for IL-1β, IL-6, IL-8, IL-10, and TNF-α by cytokine bead array. IL-1β, TNF-α, and IL-6 were significantly elevated in PRBC groups versus control. D42 NLR PRBC supernatant significantly increased secretion of IL-1β and IL-6 compared to D1 NLR PRBC supernatant. LR significantly attenuated the cytokine response of IL-1β. Thus, PRBC supernatant potentiates proinflammatory LPS-induced cytokine secretion from PBMCs. This response is accentuated with storage duration and partially attenuated with leukoreduction. These findings may partially explain the immune activation seen clinically after blood transfusion. PMID:19441884

  8. Red Blood Cell Antibody Identification

    MedlinePlus

    ... name: Red Blood Cell Antibody Identification Related tests: Direct Antiglobulin Test ; RBC Antibody Screen ; Blood Typing ; Type ... a positive RBC antibody screen or a positive direct antiglobulin test (DAT) . It is used to identify ...

  9. Dog Red Blood Cells

    PubMed Central

    Parker, John C.

    1973-01-01

    Dog red blood cells (RBC) lack a ouabain-sensitive sodium pump, and yet they are capable of volume regulation in vivo. The present study was designed to find in vitro conditions under which dog RBC could transport sodium outward, against an electrochemical gradient. Cells were first loaded with sodium chloride and water by preincubation in hypertonic saline. They were then incubated at 37°C in media containing physiologic concentrations of sodium, potassium, chloride, bicarbonate, glucose, and calcium. The cells returned to a normal salt and water content in 16–20 h. Without calcium in the medium the cells continued slowly to accumulate sodium. Removal of glucose caused rapid swelling and lysis, whether or not calcium was present. The net efflux of sodium showed a close relationship to medium calcium over a concentration range from 0 to 5 mM. Extrusion of salt and water was also demonstrated in fresh RBC (no hypertonic preincubation) when calcium levels in the media were sufficiently raised. The ion and water movements in these experiments were not influenced by ouabain or by removal of extracellular potassium. Magnesium could not substitute for calcium. It is concluded that dog RBC have an energy-dependent mechanism for extruding sodium chloride which requires external calcium and is quite distinct from the sodium-potassium exchange pump. PMID:4722565

  10. Red blood cells, spherocytosis (image)

    MedlinePlus

    Spherocytosis is a hereditary disorder of the red blood cells (RBCs), which may be associated with a mild anemia. Typically, the affected RBCs are small, spherically shaped, and lack the light centers seen ...

  11. Red blood cells, multiple sickle cells (image)

    MedlinePlus

    Sickle cell anemia is an inherited disorder in which abnormal hemoglobin (the red pigment inside red blood cells) is produced. The abnormal hemoglobin causes red blood cells to assume a sickle shape, like the ones seen in this photomicrograph.

  12. Red blood cells, sickle cell (image)

    MedlinePlus

    ... is an inherited blood disease in which the red blood cells produce abnormal pigment (hemoglobin). The abnormal hemoglobin causes deformity of the red blood cells into crescent or sickle-shapes, as seen in ...

  13. The effects of storage of red blood cells on the development of postoperative infections after noncardiac surgery.

    PubMed

    Spadaro, Savino; Taccone, Fabio Silvio; Fogagnolo, Alberto; Fontana, Vito; Ragazzi, Riccardo; Verri, Marco; Valpiani, Giorgia; Greco, Pantaleo; Bianconi, Margherita; Govoni, Maurizio; Reverberi, Roberto; Volta, Carlo Alberto

    2017-08-07

    Prolonged storage of red blood cells (RBCs) is a potential risk factor for postoperative infections. The objective of this study was to examine the effect of age of RBCs transfused on development of postoperative infection. In this prospective, double-blind randomized trial, 199 patients undergoing elective noncardiac surgery and requiring RBC transfusion were assigned to receive nonleukoreduced RBCs stored for not more than 14 days ("fresh blood" group, n = 101) or for more than 14 days ("old blood" group, n = 98). The primary outcome was occurrence of infection within 28 days after surgery; secondary outcomes were postoperative acute kidney injury (AKI), in-hospital and 90-day mortality, admission to intensive care unit, and hospital length of stay (LOS). As older blood was not always available, an "as-treated" (AT) analysis was also performed according to actual age of the RBCs transfused. The median [interquartile range] storage time of RBCs was 6 [5-10] and 15 [11-20] days in fresh blood and in old blood groups, respectively. The occurrence of postoperative infection did not differ between groups (fresh blood 22% vs. old blood 25%; relative risk [RR], 1.17; confidence interval [CI], 0.71-1.93), although wound infections occurred more frequently in old blood (15% vs. 5%; RR, 3.09; CI, 1.17- 8.18). Patients receiving older units had a higher rate of AKI (24% vs. 6%; p < 0.001) and, according to AT analysis, longer LOS (mean difference, 3.6 days; CI, 0.6-7.5). Prolonged RBC storage time did not increase the risk of postoperative infection. However, old blood transfusion increased wound infections rate and incidence of AKI. © 2017 The Authors Transfusion published by Wiley Periodicals, Inc. on behalf of AABB.

  14. 21 CFR 640.10 - Red Blood Cells.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 7 2011-04-01 2010-04-01 true Red Blood Cells. 640.10 Section 640.10 Food and... ADDITIONAL STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Red Blood Cells § 640.10 Red Blood Cells. The proper name of this product shall be Red Blood Cells. The product is defined as red blood cells...

  15. 21 CFR 640.10 - Red Blood Cells.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 7 2010-04-01 2010-04-01 false Red Blood Cells. 640.10 Section 640.10 Food and... ADDITIONAL STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Red Blood Cells § 640.10 Red Blood Cells. The proper name of this product shall be Red Blood Cells. The product is defined as red blood cells...

  16. 21 CFR 640.10 - Red Blood Cells.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 7 2014-04-01 2014-04-01 false Red Blood Cells. 640.10 Section 640.10 Food and... ADDITIONAL STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Red Blood Cells § 640.10 Red Blood Cells. The proper name of this product shall be Red Blood Cells. The product is defined as red blood cells...

  17. 21 CFR 640.10 - Red Blood Cells.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 7 2012-04-01 2012-04-01 false Red Blood Cells. 640.10 Section 640.10 Food and... ADDITIONAL STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Red Blood Cells § 640.10 Red Blood Cells. The proper name of this product shall be Red Blood Cells. The product is defined as red blood cells...

  18. 21 CFR 640.10 - Red Blood Cells.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 7 2013-04-01 2013-04-01 false Red Blood Cells. 640.10 Section 640.10 Food and... ADDITIONAL STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Red Blood Cells § 640.10 Red Blood Cells. The proper name of this product shall be Red Blood Cells. The product is defined as red blood cells...

  19. Uptake of carnitine by red blood cells

    SciTech Connect

    Campa, M.; Borum, P.

    1986-05-01

    A significant amount of blood carnitine (70% of cord blood and 40% of blood from healthy adults) is partitioned into the red blood cell compartment of whole blood. Data indicate that the plasma compartment and the red blood cell compartment of whole blood represent different metabolic pools of carnitine. There are no data to indicate that red blood cells synthesize carnitine, but our understanding of the uptake of carnitine by red blood cells is negligible. Red blood cells were obtained from healthy adults, washed twice with normal saline, and used for uptake experiments. When the cells were incubated at 37/sup 0/C in the presence of /sup 14/C-carnitine, radioactivity was found both in the soluble cytosolic and membrane fractions of the cells following lysis. The uptake was dependent upon the time of incubation, temperature of incubation, and carnitine concentration in the incubation medium. Washed red blood cell membranes incubated with /sup 14/C-carnitine showed specific binding of radioactivity. These data are consistent with the hypothesis that red blood cells have an uptake mechanism for L-carnitine.

  20. Red blood cell decreases of microgravity

    NASA Technical Reports Server (NTRS)

    Johnson, P. C.

    1985-01-01

    Postflight decreases in red blood cell mass (RBCM) have regularly been recorded after exposure to microgravity. These 5-25 percent decreases do not relate to the mission duration, workload, caloric intake or to the type of spacecraft used. The decrease is accompanied by normal red cell survivals, increased ferritin levels, normal radioactive iron studies, and increases in mean red blood cell volume. Comparable decreases in red blood cell mass are not found after bed rest, a commonly used simulation of the microgravity state. Inhibited bone marrow erythropoiesis has not been proven to date, although reticulocyte numbers in the peripheral circulation are decreased about 50 percent. To date, the cause of the microgravity induced decreases in RBCM is unknown. Increased splenic trapping of circulating red blood cells seem the most logical way to explain the results obtained.

  1. Red blood cell decreases of microgravity

    NASA Technical Reports Server (NTRS)

    Johnson, P. C.

    1985-01-01

    Postflight decreases in red blood cell mass (RBCM) have regularly been recorded after exposure to microgravity. These 5-25 percent decreases do not relate to the mission duration, workload, caloric intake or to the type of spacecraft used. The decrease is accompanied by normal red cell survivals, increased ferritin levels, normal radioactive iron studies, and increases in mean red blood cell volume. Comparable decreases in red blood cell mass are not found after bed rest, a commonly used simulation of the microgravity state. Inhibited bone marrow erythropoiesis has not been proven to date, although reticulocyte numbers in the peripheral circulation are decreased about 50 percent. To date, the cause of the microgravity induced decreases in RBCM is unknown. Increased splenic trapping of circulating red blood cells seem the most logical way to explain the results obtained.

  2. Human spleen and red blood cells

    NASA Astrophysics Data System (ADS)

    Pivkin, Igor; Peng, Zhangli; Karniadakis, George; Buffet, Pierre; Dao, Ming

    2016-11-01

    Spleen plays multiple roles in the human body. Among them is removal of old and altered red blood cells (RBCs), which is done by filtering cells through the endothelial slits, small micron-sized openings. There is currently no experimental technique available that allows us to observe RBC passage through the slits. It was previously noticed that people without a spleen have less deformable red blood cells, indicating that the spleen may play a role in defining the size and shape of red blood cells. We used detailed RBC model implemented within the Dissipative Particle Dynamics (DPD) simulation framework to study the filter function of the spleen. Our results demonstrate that spleen indeed plays major role in defining the size and shape of the healthy human red blood cells.

  3. Freeze-Dried Human Red Blood Cells.

    DTIC Science & Technology

    1992-07-15

    instructed not to consume any alcohol -containing beverage during the period from seven days prior to phlebotomy to the completion of the follow-up...over the heart, spleen and liver at 4 hours and 24 hours post-infusion to determine the organ distribution of the radiolabeled reconstituted red blood...cells. 4. External probe counts taken over the heart, liver and spleen to determine the distribution of the lyophilized red blood cells at 4 hours and

  4. Sickle red blood cells accumulate in tumor.

    PubMed

    Brown, S L; Ewing, J R; Nagaraja, T N; Swerdlow, P S; Cao, Y; Fenstermacher, J D; Kim, J H

    2003-12-01

    The preferential accumulation of sickle blood cells in tumor vasculature is demonstrated noninvasively using MRI and sickle red blood cells loaded with Gd-DTPA and invasively by two other techniques. The distribution of red blood cells in rat brain tumors relative to normal brains were measured using three separate techniques: MRI of Gd-DTPA loaded cells, fluorescent microscopy detection of Oregon Green 488 fluorescence conjugated to a streptavidin-biotin complex that binds to red blood cell surface proteins, and autoradiography using a technetium (99m)Tc-labeling kit. Labeled red cells were infused intravenously in rats with brain tumors. Sickle cells preferentially accumulated in tumor relative to normal brain, with highest concentrations near the tumor / normal tissue boundary, whereas control normal red cells did not preferentially aggregate at the tumor periphery. This demonstrates the potential of sickle red blood cells to accumulate in the abnormal tumor vessel network, and the ability to detect their aggregation noninvasively and at high spatial resolution using MRI. The application of the noninvasive measurement of sickle cells for imaging tumor neovasculature, or as a delivery tool for therapy, requires further study. Copyright 2003 Wiley-Liss, Inc.

  5. Prolonged storage of packed red blood cells for blood transfusion.

    PubMed

    Martí-Carvajal, Arturo J; Simancas-Racines, Daniel; Peña-González, Barbra S

    2015-07-14

    A blood transfusion is an acute intervention, used to address life- and health-threatening conditions on a short-term basis. Packed red blood cells are most often used for blood transfusion. Sometimes blood is transfused after prolonged storage but there is continuing debate as to whether transfusion of 'older' blood is as beneficial as transfusion of 'fresher' blood. To assess the clinical benefits and harms of prolonged storage of packed red blood cells, in comparison with fresh, on recipients of blood transfusion. We ran the search on 1st May 2014. We searched the Cochrane Injuries Group Specialized Register, Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library), MEDLINE (OvidSP), Embase (OvidSP), CINAHL (EBSCO Host) and two other databases. We also searched clinical trials registers and screened reference lists of the retrieved publications and reviews. We updated this search in June 2015 but these results have not yet been incorporated. Randomised clinical trials including participants assessed as requiring red blood cell transfusion were eligible for inclusion. Prolonged storage was defined as red blood cells stored for ≥ 21 days in a blood bank. We did not apply limits regarding the duration of follow-up, or country where the study took place. We excluded trials where patients received a combination of short- and long-stored blood products, and also trials without a clear definition of prolonged storage. We independently performed study selection, risk of bias assessment and data extraction by at least two review authors. The major outcomes were death from any cause, transfusion-related acute lung injury, and adverse events. We estimated relative risk for dichotomous outcomes. We measured statistical heterogeneity using I(2). We used a random-effects model to synthesise the findings. We identified three randomised clinical trials, involving a total of 120 participants, comparing packed red blood cells with ≥ 21 days storage

  6. Inflight Assay of Red Blood Cell Deformability

    NASA Technical Reports Server (NTRS)

    Ingram, M.; Paglia, D. E.; Eckstein, E. C.; Frazer, R. E.

    1985-01-01

    Studies on Soviet and American astronauts have demonstrated that red blood cell production is altered in response to low gravity (g) environment. This is associated with changes in individual red cells including increased mean cell volume and altered membrane deformability. During long orbital missions, there is a tendency for the red cell mass deficit to be at least partly corrected although the cell shape anomalies are not. Data currently available suggest that the observed decrease in red cell mass is the result of sudden suppression of erythropoieses and that the recovery trend observed during long missions reflects re-establishment of erythropoietic homeostasis at a "set point" for the red cell mass that is slightly below the normal level at 1 g.

  7. Inflight Assay of Red Blood Cell Deformability

    NASA Technical Reports Server (NTRS)

    Ingram, M.; Paglia, D. E.; Eckstein, E. C.; Frazer, R. E.

    1985-01-01

    Studies on Soviet and American astronauts have demonstrated that red blood cell production is altered in response to low gravity (g) environment. This is associated with changes in individual red cells including increased mean cell volume and altered membrane deformability. During long orbital missions, there is a tendency for the red cell mass deficit to be at least partly corrected although the cell shape anomalies are not. Data currently available suggest that the observed decrease in red cell mass is the result of sudden suppression of erythropoieses and that the recovery trend observed during long missions reflects re-establishment of erythropoietic homeostasis at a "set point" for the red cell mass that is slightly below the normal level at 1 g.

  8. Anesthetics and red blood cell rheology

    NASA Astrophysics Data System (ADS)

    Aydogan, Burcu; Aydogan, Sami

    2014-05-01

    There are many conditions where it is useful for anesthetists to have a knowledge of blood rheology. Blood rheology plays an important role in numerous clinical situations. Hemorheologic changes may significantly affect the induction and recovery times with anesthetic agents. But also, hemorheologic factors are directly or indirectly affected by many anesthetic agents or their metabolites. In this review, the blood rheology with special emphasis on its application in anesthesiology, the importance hemorheological parameters in anesthesiology and also the effect of some anesthetic substances on red blood cell rheology were presented.

  9. Red blood cell transfusion in newborn infants

    PubMed Central

    Whyte, Robin K; Jefferies, Ann L

    2014-01-01

    Red blood cell transfusion is an important and frequent component of neonatal intensive care. The present position statement addresses the methods and indications for red blood cell transfusion of the newborn, based on a review of the current literature. The most frequent indications for blood transfusion in the newborn are the acute treatment of perinatal hemorrhagic shock and the recurrent correction of anemia of prematurity. Perinatal hemorrhagic shock requires immediate treatment with large quantities of red blood cells; the effects of massive transfusion on other blood components must be considered. Some guidelines are now available from clinical trials investigating transfusion in anemia of prematurity; however, considerable uncertainty remains. There is weak evidence that cognitive impairment may be more severe at follow-up in extremely low birth weight infants transfused at lower hemoglobin thresholds; therefore, these thresholds should be maintained by transfusion therapy. Although the risks of transfusion have declined considerably in recent years, they can be minimized further by carefully restricting neonatal blood sampling. PMID:24855419

  10. Blood Shortage Prompts Red Cross Call for Donations

    MedlinePlus

    ... html Blood Shortage Prompts Red Cross Call for Donations Says decline in donors seen over holidays To ... 2017 FRIDAY, Jan. 6, 2017 (HealthDay News) -- Blood donations to the American Red Cross have slumped recently, ...

  11. Interferometric phase microscopy of red blood cells

    NASA Astrophysics Data System (ADS)

    Xue, Liang; Sun, Nan; Tang, Xian; Wang, Yin; Wang, Shouyu

    2013-12-01

    Quantitative phase imaging of cells with high accuracy in a completely noninvasive manner is a challenging task. To provide a proper solution to this important need, interferometric phase microscopy is described which relies on the off-axis interferometry, confocal microscopy and high-speed image capture technology. Phase retrieval from the single interferogram is done by algorithms based on the fast Fourier transform, traditional Hilbert transform and two-step Hilbert transform, respectively. Furthermore, a phase aberrations compensation approach is applied to correct the phase distribution of the red blood cells obtained via the three methods mentioned before without the pre-known knowledge for removing the wave front curvature introduced by the microscope objectives, off-axis imaging, etc., which otherwise hinders the phase reconstruction. The improved results reveal the better inner structures of the red blood cells. The development of quantitative phase imaging technique is shedding light on their future directions and applications for basic and clinical research.

  12. Freeze-Dried Human Red Blood Cells

    DTIC Science & Technology

    1992-04-15

    chromium labelled mRBC via an intravenous catheter in the peripheral saphenous vein . Following administration of labelled mRBC into each monkey, 0.2ml...with a single dose of autologous , lyophilized and reconstituted, 5 1Cr-labelled packed erythrocytes via an intravenous catheter in a peripheral vein ...study site, at which time a 25 ml aliquot of reconstituted 51-Cr labeled autologous red blood cells will be infused intravenously into a large arm vein

  13. 21 CFR 660.30 - Reagent Red Blood Cells.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 7 2011-04-01 2010-04-01 true Reagent Red Blood Cells. 660.30 Section 660.30 Food... ADDITIONAL STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Reagent Red Blood Cells § 660.30 Reagent Red Blood Cells. (a) Proper name and definition. The proper name of the product shall be Reagent...

  14. 21 CFR 660.30 - Reagent Red Blood Cells.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 7 2010-04-01 2010-04-01 false Reagent Red Blood Cells. 660.30 Section 660.30...) BIOLOGICS ADDITIONAL STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Reagent Red Blood Cells § 660.30 Reagent Red Blood Cells. (a) Proper name and definition. The proper name of the product shall...

  15. 21 CFR 660.30 - Reagent Red Blood Cells.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 7 2012-04-01 2012-04-01 false Reagent Red Blood Cells. 660.30 Section 660.30...) BIOLOGICS ADDITIONAL STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Reagent Red Blood Cells § 660.30 Reagent Red Blood Cells. (a) Proper name and definition. The proper name of the product shall...

  16. 21 CFR 660.30 - Reagent Red Blood Cells.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 7 2014-04-01 2014-04-01 false Reagent Red Blood Cells. 660.30 Section 660.30...) BIOLOGICS ADDITIONAL STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Reagent Red Blood Cells § 660.30 Reagent Red Blood Cells. (a) Proper name and definition. The proper name of the product shall...

  17. 21 CFR 660.30 - Reagent Red Blood Cells.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 7 2013-04-01 2013-04-01 false Reagent Red Blood Cells. 660.30 Section 660.30...) BIOLOGICS ADDITIONAL STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Reagent Red Blood Cells § 660.30 Reagent Red Blood Cells. (a) Proper name and definition. The proper name of the product shall...

  18. 21 CFR 864.7100 - Red blood cell enzyme assay.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Red blood cell enzyme assay. 864.7100 Section 864...) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Kits and Packages § 864.7100 Red blood cell enzyme assay. (a) Identification. Red blood cell enzyme assay is a device used to measure the activity in...

  19. 21 CFR 864.7100 - Red blood cell enzyme assay.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Red blood cell enzyme assay. 864.7100 Section 864...) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Kits and Packages § 864.7100 Red blood cell enzyme assay. (a) Identification. Red blood cell enzyme assay is a device used to measure the activity in...

  20. 21 CFR 864.7100 - Red blood cell enzyme assay.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Red blood cell enzyme assay. 864.7100 Section 864...) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Kits and Packages § 864.7100 Red blood cell enzyme assay. (a) Identification. Red blood cell enzyme assay is a device used to measure the activity in...

  1. 21 CFR 864.7100 - Red blood cell enzyme assay.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Red blood cell enzyme assay. 864.7100 Section 864...) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Kits and Packages § 864.7100 Red blood cell enzyme assay. (a) Identification. Red blood cell enzyme assay is a device used to measure the activity in...

  2. Red blood cells in retinal vascular disorders.

    PubMed

    Agrawal, Rupesh; Sherwood, Joseph; Chhablani, Jay; Ricchariya, Ashutosh; Kim, Sangho; Jones, Philip H; Balabani, Stavroula; Shima, David

    2016-01-01

    Microvascular circulation plays a vital role in regulating physiological functions, such as vascular resistance, and maintaining organ health. Pathologies such as hypertension, diabetes, or hematologic diseases affect the microcirculation posing a significant risk to human health. The retinal vasculature provides a unique window for non-invasive visualisation of the human circulation in vivo and retinal vascular image analysis has been established to predict the development of both clinical and subclinical cardiovascular, metabolic, renal and retinal disease in epidemiologic studies. Blood viscosity which was otherwise thought to play a negligible role in determining blood flow based on Poiseuille's law up to the 1970s has now been shown to play an equally if not a more important role in controlling microcirculation and quantifying blood flow. Understanding the hemodynamics/rheology of the microcirculation and its changes in diseased states remains a challenging task; this is due to the particulate nature of blood, the mechanical properties of the cells (such as deformability and aggregability) and the complex architecture of the microvasculature. In our review, we have tried to postulate a possible role of red blood cell (RBC) biomechanical properties and laid down future framework for research related to hemorrheological aspects of blood in patients with retinal vascular disorders.

  3. Mechanosensing Dynamics of Red blood Cells

    NASA Astrophysics Data System (ADS)

    Wan, Jiandi

    2015-11-01

    Mechanical stress-induced deformation of human red blood cells (RBCs) plays important physiopathological roles in oxygen delivery, blood rheology, transfusion, and malaria. Recent studies demonstrate that, in response to mechanical deformation, RBCs release adenosine-5'-triphosphate (ATP), suggesting the existence of mechanotransductive pathways in RBCs. Most importantly, the released ATP from RBCs regulates vascular tone and impaired release of ATP from RBCs has been linked to diseases such as type II diabetes and cystic fibrosis. To date, however, the mechanisms of mechanotransductive release of ATP from RBCs remain unclear. Given that RBCs experience shear stresses continuously during the circulation cycle and the released ATP plays a central role in vascular physiopathology, understanding the mechanotransductive release of ATP from RBCs will provide not only fundamental insights to the role of RBCs in vascular homeostasis but also novel therapeutic strategies for red cell dysfunction and vascular disease. This talk describes the main research in my group on integrating microfluidic-based approaches to study the mechanosensing dynamics of RBCs. Specifically, I will introduce a micro?uidic approach that can probe the dynamics of shear-induced ATP release from RBCs with millisecond resolution and provide quantitative understandings of the mechanosensitive ATP release processes in RBCs. Furthermore, I will also describe our recent findings about the roles of the Piezo1 channel, a newly discovered mechanosensitive cation channel in the mechanotransductive ATP release in RBCs. Last, possible functions of RBCs in the regulation of cerebral blood flow will be discussed.

  4. Red Blood Cell Count Automation Using Microscopic Hyperspectral Imaging Technology.

    PubMed

    Li, Qingli; Zhou, Mei; Liu, Hongying; Wang, Yiting; Guo, Fangmin

    2015-12-01

    Red blood cell counts have been proven to be one of the most frequently performed blood tests and are valuable for early diagnosis of some diseases. This paper describes an automated red blood cell counting method based on microscopic hyperspectral imaging technology. Unlike the light microscopy-based red blood count methods, a combined spatial and spectral algorithm is proposed to identify red blood cells by integrating active contour models and automated two-dimensional k-means with spectral angle mapper algorithm. Experimental results show that the proposed algorithm has better performance than spatial based algorithm because the new algorithm can jointly use the spatial and spectral information of blood cells.

  5. Red blood cell transfusion in clinical practice.

    PubMed

    Klein, Harvey G; Spahn, Donat R; Carson, Jeffrey L

    2007-08-04

    Every year, about 75 million units of blood are collected worldwide. Red blood cell (RBC) transfusion is one of the few treatments that adequately restore tissue oxygenation when oxygen demand exceeds supply. Although the respiratory function of blood has been studied intensively, the trigger for RBC transfusion remains controversial, and doctors rely primarily on clinical experience. Laboratory assays that indicate failing tissue oxygenation would be ideal to guide the need for transfusion, but none has proved easy, reproducible, and sensitive to regional tissue hypoxia. The clinical importance of the RBCs storage lesion (ie, the time-dependent metabolic, biochemical, and molecular changes that stored blood cells undergo) is poorly understood. RBCs can be filtered, washed, frozen, or irradiated for specific indications. Donor screening and testing have dramatically reduced infectious risks in the developed world, but infection remains a major hazard in developing countries, where 13 million units of blood are not tested for HIV or hepatitis viruses. Pathogen inactivation techniques are in clinical trials for RBCs, but none is available for use. Despite serious immunological and non-immunological complications, RBC transfusion holds a therapeutic index that exceeds that of many common medications.

  6. [Immunological blood transfusion safety and selection of red blood cells issued from hospital blood banks].

    PubMed

    Py, J-Y

    2010-12-01

    Allogeneic red blood cells transfusion is always an immunological challenge and the choice of the blood products is crucial for the patient safety. But this choice may be hampered by the quality or the quantity of the available supply. In the end, the lack of transfusion may be more harmful than transfusion. The balance between patients' needs and blood centres supplying is always delicate. The conditions are not the same for all blood groups. Things are easier for the KEL1 phenotype, where the supply must ensure only 92.5% of KEL: -1 red blood cells instead of the 91% expected. More complicated is the situation for group O red blood cells with 47 versus 43%. But the major problem concerns RH: -1 red blood cells, for which the needs reach 20.1 versus 15%. These challenges require a lot of efforts from blood centres staffs to influence blood donors' recruitment and appointments. A justified and carefully selected blood products issuing may be of great help, especially for group O RH: -1 red blood cells. Therefore, hospital blood banks must have ad hoc procedures and a trained staff to put them into practice.

  7. Multiscale simulation of red blood cell aggregation

    NASA Astrophysics Data System (ADS)

    Bagchi, P.; Popel, A. S.

    2004-11-01

    In humans and other mammals, aggregation of red blood cells (RBC) is a major determinant to blood viscosity in microcirculation under physiological and pathological conditions. Elevated levels of aggregation are often related to cardiovascular diseases, bacterial infection, diabetes, and obesity. Aggregation is a multiscale phenomenon that is governed by the molecular bond formation between adjacent cells, morphological and rheological properties of the cells, and the motion of the extra-cellular fluid in which the cells circulate. We have developed a simulation technique using front tracking methods for multiple fluids that includes the multiscale characteristics of aggregation. We will report the first-ever direct computer simulation of aggregation of deformable cells in shear flows. We will present results on the effect of shear rate, strength of the cross-bridging bonds, and the cell rheological properties on the rolling motion, deformation and subsequent breakage of an aggregate.

  8. Optical analysis of red blood cell suspension

    NASA Astrophysics Data System (ADS)

    Szołna, Alicja A.; Grzegorzewski, Bronisław

    2008-12-01

    The optical properties of suspensions of red blood cells (RBCs) were studied. Fresh human venues blood was obtained from adult healthy donors. RBCs were suspended in isotonic salt solution, and in autologous plasma. Suspensions with haematocrit 0.25 - 3% were investigated. Novel technique was proposed to determine the scattering coefficient μs for the suspensions. The intensity of He-Ne laser light transmitted through a wedge-shape container filled with a suspension was recorded. To find the dependence of the intensity on the thickness of the sample the container was moved horizontally. The dependence of μs on the haematocrit was determined for RBCs suspended in the isotonic salt solution. RBCs suspended in plasma tend to form rouleaux. For the RBCs suspended in plasma, the scattering coefficient as a function of time was obtained. It is shown that this technique can be useful in the study of rouleaux formation.

  9. Hemodynamic effects of red blood cell aggregation.

    PubMed

    Baskurt, Oguz K; Meiselman, Herbert J

    2007-01-01

    The influence of red blood cell (RBC) aggregation on blood flow in vivo has been under debate since early 1900's, yet a full understanding has still has not been reached. Enhanced RBC aggregation is well known to increase blood viscosity measured in rotational viscometers. However, it has been demonstrated that RBC aggregation may decrease flow resistance in cylindrical tubes, due to the formation of a cell-poor zone near the tube wall which results from the enhanced central accumulation of RBC. There is also extensive discussion regarding the effects of RBC aggregation on in vivo blood flow resistance. Several groups have reported increased microcirculatory flow resistance with enhanced RBC aggregation in experiments that utilized intravital microscopy. Alternatively, whole organ studies revealed that flow resistance may be significantly decreased if RBC aggregation is enhanced. Recently, new techniques have been developed to achieve well-controlled, graded alterations in RBC aggregation without influencing suspending phase properties. Studies using this technique revealed that the effects of RBC aggregation are determined by the degree of aggregation changes, and that this relationship can be explained by different hemodynamic mechanisms.

  10. Red blood cell storage and cell morphology.

    PubMed

    Blasi, B; D'Alessandro, A; Ramundo, N; Zolla, L

    2012-04-01

    In this study, we performed weekly assessment of morphology-related parameters through monitoring of CPD-SAGM leuco-filtered erythrocyte concentrates from blood withdrawal until the 42nd day of storage. Liquid storage of red blood cells (RBCs) delivers a blood-derived therapeutic, which is safe, available, effective and affordable for most patients who need transfusion therapy in developed countries. However, a growing body of accumulating controversial evidences, from either biochemical or retrospective clinical studies, prompted safety concerns about longer stored RBCs. Statistical image analysis through scanning electron microscope was coupled to osmotic fragility and erythrocyte sedimentation rate. We could observe that by day 21 more than 50% of RBCs displayed non-discocyte phenotypes. This observation was related to an increase in osmotic fragility, which was totally overlapped in day 0 controls and day 7 RBCs while only slightly augmented in day 14 samples. Cation dysregulation (pH internal/external alteration and potassium) might both reflect and trigger a negative feedback loop with metabolic fluxes and membrane cation pumps. Morphology parameters suggest that significant alterations to RBC morphology over storage duration occur soon after the 14th day of storage, as to become significant enough within the 21st day. © 2012 The Authors. Transfusion Medicine © 2012 British Blood Transfusion Society.

  11. Understanding red blood cell alloimmunization triggers.

    PubMed

    Hendrickson, Jeanne E; Tormey, Christopher A

    2016-12-02

    Blood group alloimmunization is "triggered" when a person lacking a particular antigen is exposed to this antigen during transfusion or pregnancy. Although exposure to an antigen is necessary for alloimmunization to occur, it is not alone sufficient. Blood group antigens are diverse in structure, function, and immunogenicity. In addition to red blood cells (RBCs), a recipient of an RBC transfusion is exposed to donor plasma, white blood cells, and platelets; the potential contribution of these elements to RBC alloimmunization remains unclear. Much attention in recent years has been placed on recipient factors that influence RBC alloantibody responses. Danger signals, identified in murine and human studies alike as being risk factors for alloimmunization, may be quite diverse in nature. In addition to exogenous or condition-associated inflammation, autoimmunity is also a risk factor for alloantibody formation. Triggers for alloimmunization in pregnancy are not well-understood beyond the presence of a fetal/maternal bleed. Studies using animal models of pregnancy-induced RBC alloimmunization may provide insight in this regard. A better understanding of alloimmunization triggers and signatures of "responders" and "nonresponders" is needed for prevention strategies to be optimized. A common goal of such strategies is increased transfusion safety and improved pregnancy outcomes.

  12. Red blood cell replacement, or nanobiotherapeutics with enhanced red blood cell functions?

    PubMed

    Chang, Thomas Ming Swi

    2015-06-01

    Why is this important? Under normal circumstances, donor blood is the best replacement for blood. However, there are exceptions: During natural epidemics (e.g., HIV, Ebola, etc.) or man-made epidemics (terrorism, war, etc.), there is a risk of donor blood being contaminated, and donors being disqualified because they have contracted disease. Unlike red blood cells (RBCs), blood substitutes can be sterilized to remove infective agents. Heart attack and stroke are usually caused by obstruction of arterial blood vessels. Unlike RBCs, which are particulate, blood substitutes are in the form of a solution that can perfuse through obstructed vessels with greater ease to reach the heart and brain, as has been demonstrated in animal studies. Severe blood loss from injuries sustained during accidents, disasters, or war may require urgent blood transfusion that cannot wait for transportation to the hospital for blood group testing. Unlike RBCs, blood substitutes do not have specific blood groups, and can be administered on the spot. RBCs have to be stored under refrigeration for up to 42 days, and are thus difficult to transport and store in times of disaster and at the battlefront. Blood substitutes can be stored at room temperature for more than 1 year, compared to the RBC shelf life of 1 day, at room temperature. In cases of very severe hemorrhagic shock, there is usually a safety window of 60 min for blood replacement, beyond which there could be problems related to irreversible shock. Animal studies show that a particular type of blood substitute, with enhanced RBC enzymes, may be able to prolong the duration of the safety window.

  13. Reversibility of red blood cell deformation

    NASA Astrophysics Data System (ADS)

    Zeitz, Maria; Sens, P.

    2012-05-01

    The ability of cells to undergo reversible shape changes is often crucial to their survival. For red blood cells (RBCs), irreversible alteration of the cell shape and flexibility often causes anemia. Here we show theoretically that RBCs may react irreversibly to mechanical perturbations because of tensile stress in their cytoskeleton. The transient polymerization of protein fibers inside the cell seen in sickle cell anemia or a transient external force can trigger the formation of a cytoskeleton-free membrane protrusion of μm dimensions. The complex relaxation kinetics of the cell shape is shown to be responsible for selecting the final state once the perturbation is removed, thereby controlling the reversibility of the deformation. In some case, tubular protrusion are expected to relax via a peculiar “pearling instability.”

  14. Reversibility of red blood cell deformation.

    PubMed

    Zeitz, Maria; Sens, P

    2012-05-01

    The ability of cells to undergo reversible shape changes is often crucial to their survival. For red blood cells (RBCs), irreversible alteration of the cell shape and flexibility often causes anemia. Here we show theoretically that RBCs may react irreversibly to mechanical perturbations because of tensile stress in their cytoskeleton. The transient polymerization of protein fibers inside the cell seen in sickle cell anemia or a transient external force can trigger the formation of a cytoskeleton-free membrane protrusion of μm dimensions. The complex relaxation kinetics of the cell shape is shown to be responsible for selecting the final state once the perturbation is removed, thereby controlling the reversibility of the deformation. In some case, tubular protrusion are expected to relax via a peculiar "pearling instability."

  15. Fluorometric assay for red blood cell antibodies

    SciTech Connect

    Schreiber, A.B.; Lambermont, M.; Strosberg, A.D.; Wybran, J.

    1981-03-01

    A fluorometric assay is described for the detection of red blood cell antibodies. The assay reveals as little as 600 molecules of bound, fluoroesceinated rabbit anti-human IgG antibodies per erythrocyte. Eleven patients with possible autoimmune erythrocyte disorder and negative direct antiglobulin test were studied by the fluorometric assay. The outcome of the fluorometric assay was compared with that of the human allogeneic rosette test. Results obtained by the two methods were in complete agreement. Five of the patients were shown to possess unexpectedly high levels of erythrocyte-bound IgG in spite of a negative, direct antiglobulin test. These findings and the validity of the fluorometric assay are discussed.

  16. Red blood cell volume in preterm neonates

    SciTech Connect

    Quaife, M.A.; Dirksen, J.W.; Paxson, C.L. Jr.; McIntire, R.H. Jr.

    1981-10-01

    In the high-risk neonate, the direct determination of the red cell volume by radionuclide dilution technique appears to be the singularly definitive method of defining treatment efficacy, and is thus a useful evaluation and management tool for the pediatrician. For effective patient management, the red blood cell(RBC) volume of 69 preterm and term neonates was determined. The method utilized, Tc-99m-labeled RBCs, provided a fast and accurate answer with a large reduction in the absorbed radiation dose. In the population studied within a high-risk newborn ICU, the mean RBC volumes between the preterm and term neonates were without significant difference. Grouping and analysis of the RBC volume data with respect to birth weight, gestational ages, and 1- and 5-minute Apgar scores revealed on statistical difference. The mean value found in our population, 32.2 +/- 9.2 ml/kg, however, does differ from those previously reported in which the determinations were made using an indirect estimation from the plasma compartment.

  17. Microconfined flow behavior of red blood cells.

    PubMed

    Tomaiuolo, Giovanna; Lanotte, Luca; D'Apolito, Rosa; Cassinese, Antonio; Guido, Stefano

    2016-01-01

    Red blood cells (RBCs) perform essential functions in human body, such as gas exchange between blood and tissues, thanks to their ability to deform and flow in the microvascular network. The high RBC deformability is mainly due to the viscoelastic properties of the cell membrane. Since an impaired RBC deformability could be found in some diseases, such as malaria, sickle cell anemia, diabetes and hereditary disorders, there is the need to provide further insight into measurement of RBC deformability in a physiologically relevant flow field. Here, RBCs deformability has been studied in terms of the minimum apparent plasma-layer thickness by using high-speed video microscopy of RBCs flowing in cylindrical glass capillaries. An in vitro systematic microfluidic investigation of RBCs in micro-confined conditions has been performed, resulting in the determination of the RBCs time recovery constant, RBC volume and surface area and RBC membrane shear elastic modulus and surface viscosity. It has been noticed that the deformability of RBCs induces cells aggregation during flow in microcapillaries, allowing the formation of clusters of cells. Overall, our results provide a novel technique to estimate RBC deformability and also RBCs collective behavior, which can be used for the analysis of pathological RBCs, for which reliable quantitative methods are still lacking.

  18. Effects of red blood cells on hemostasis.

    PubMed

    Roeloffzen, Wilfried W H; Kluin-Nelemans, Hanneke C; Bosman, Lotte; de Wolf, Joost Th M

    2010-07-01

    Currently there is no sensitive laboratory test to establish the influence of red blood cells (RBCs) on hemostasis. As thromboelastography (TEG) measures hemostasis in whole blood, taking into account the interactions of all cellular elements, we used this instrument to investigate the role that RBCs play in hemostasis. In 29 patients with chemotherapy-induced anemia we studied the effect of progressive anemia on the coagulation profile. In 24 patients with chronic anemia we studied the effect of transfusion of RBCs on coagulation. Finally, in 18 patients we evaluated whether storage time of RBCs has additional effects on hemostasis. We observed a significant negative correlation between hemoglobin and TEG variables related to both clot strength and elasticity (p < 0.05). Moreover, anemia was associated with a delay in the initiation of the coagulation cascade. Correction of anemia by RBC transfusion resulted in significant shortening of this initiation phase with now the opposite effect on clot strength and elasticity. The negative effects on clot quality were significantly worse when fresh RBCs were transfused compared to longer-stored RBCs. Furthermore, in contrast to the longer-stored RBCs, fresh RBCs did not enhance initial fibrin formation. In this study we found that anemia was associated with a delay in the initiation of the coagulation cascade with a finally formed clot with superior strength and viscoelastic properties. Transfusion of RBCs was associated with impaired clot quality, with even worse effects on the initial fibrin build-up and clot quality by fresh RBCs.

  19. Red blood cell storage duration and trauma.

    PubMed

    Sparrow, Rosemary L

    2015-04-01

    Numerous retrospective clinical studies suggest that transfusion of longer stored red blood cells (RBCs) is associated with an independent risk of poorer outcomes for certain groups of patients, including trauma, intensive care, and cardiac surgery patients. Large multicenter randomized controlled trials are currently underway to address the concern about RBC storage duration. However, none of these randomized controlled trials focus specifically on trauma patients with hemorrhage. Major trauma, particularly due to road accidents, is the leading cause of critical injury in the younger-than-40-year-old age group. Severe bleeding associated with major trauma induces hemodynamic dysregulation that increases the risk of hypoxia, coagulopathy, and potentially multiorgan failure, which can be fatal. In major trauma, a multitude of stress-associated changes occur to the patient's RBCs, including morphological changes that increase cell rigidity and thereby alter blood flow hemodynamics, particularly in the microvascular vessels, and reduce RBC survival. Initial inflammatory responses induce deleterious cellular interactions, including endothelial activation, RBC adhesion, and erythrophagocytosis that are quickly followed by profound immunosuppressive responses. Stored RBCs exhibit similar biophysical characteristics to those of trauma-stressed RBCs. Whether transfusion of RBCs that exhibit storage lesion changes exacerbates the hemodynamic perturbations already active in the trauma patient is not known. This article reviews findings from several recent nonrandomized studies examining RBC storage duration and clinical outcomes in trauma patients. The rationale for further research on RBC storage duration in the trauma setting is provided. Copyright © 2015 Elsevier Inc. All rights reserved.

  20. Destruction of newly released red blood cells in space flight

    NASA Technical Reports Server (NTRS)

    Alfrey, C. P.; Udden, M. M.; Huntoon, C. L.; Driscoll, T.

    1996-01-01

    Space flight results in a rapid change in total blood volume, plasma volume, and red blood cell mass because the space to contain blood is decreased. The plasma volume and total blood volume decreases during the first hours in space and remain at a decreased level for the remainder of the flight. During the first several hours following return to earth, plasma volume and total blood volume increase to preflight levels. During the first few days in space recently produced red blood cells disappear from the blood resulting in a decrease in red blood cell mass of 10-15%. Red cells 12 d old or older survive normally and production of new cells continues at near preflight levels. After the first few days in space, the red cell mass is stable at the decreased level. Following return to earth the hemoglobin and red blood cell mass concentrations decrease reflecting the increase in plasma volume. The erythropoietin levels increase responding to "postflight anemia"; red cell production increases, and the red cell mass is restored to preflight levels after several weeks.

  1. Destruction of newly released red blood cells in space flight

    NASA Technical Reports Server (NTRS)

    Alfrey, C. P.; Udden, M. M.; Huntoon, C. L.; Driscoll, T.

    1996-01-01

    Space flight results in a rapid change in total blood volume, plasma volume, and red blood cell mass because the space to contain blood is decreased. The plasma volume and total blood volume decreases during the first hours in space and remain at a decreased level for the remainder of the flight. During the first several hours following return to earth, plasma volume and total blood volume increase to preflight levels. During the first few days in space recently produced red blood cells disappear from the blood resulting in a decrease in red blood cell mass of 10-15%. Red cells 12 d old or older survive normally and production of new cells continues at near preflight levels. After the first few days in space, the red cell mass is stable at the decreased level. Following return to earth the hemoglobin and red blood cell mass concentrations decrease reflecting the increase in plasma volume. The erythropoietin levels increase responding to "postflight anemia"; red cell production increases, and the red cell mass is restored to preflight levels after several weeks.

  2. Characterization of red blood cell deformability change during blood storage.

    PubMed

    Zheng, Yi; Chen, Jun; Cui, Tony; Shehata, Nadine; Wang, Chen; Sun, Yu

    2014-02-07

    Stored red blood cells (RBCs) show progressive deformability changes during blood banking/storage. Their deformability changes over an 8 weeks' storage period were measured using a microfluidic device. Hydrodynamic focusing controls the orientation and position of individual RBCs within the microchannel. High-speed imaging (5000 frames s(-1)) captures the dynamic deformation behavior of the cells, and together with automated image analysis, enables the characterization of over 1000 RBCs within 3 minutes. Multiple parameters including deformation index (DI), time constant (shape recovery rate), and RBC circularity were quantified. Compared to previous studies on stored RBC deformability, our results include a significantly higher number of cells (>1000 cells per sample vs. a few to tens of cells per sample) and, for the first time, reveal deformation changes of stored RBCs when traveling through human-capillary-like microchannels. Contrary to existing knowledge, our results demonstrate that the deformation index of RBCs under folding does not change significantly over blood storage. However, significant differences exist in time constants and circularity distribution widths, which can be used to quantify stored RBC quality or age.

  3. 21 CFR 864.7100 - Red blood cell enzyme assay.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Red blood cell enzyme assay. 864.7100 Section 864.7100 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Kits and Packages § 864.7100 Red blood...

  4. Red blood cells in sports: effects of exercise and training on oxygen supply by red blood cells.

    PubMed

    Mairbäurl, Heimo

    2013-01-01

    During exercise the cardiovascular system has to warrant substrate supply to working muscle. The main function of red blood cells in exercise is the transport of O2 from the lungs to the tissues and the delivery of metabolically produced CO2 to the lungs for expiration. Hemoglobin also contributes to the blood's buffering capacity, and ATP and NO release from red blood cells contributes to vasodilation and improved blood flow to working muscle. These functions require adequate amounts of red blood cells in circulation. Trained athletes, particularly in endurance sports, have a decreased hematocrit, which is sometimes called "sports anemia." This is not anemia in a clinical sense, because athletes have in fact an increased total mass of red blood cells and hemoglobin in circulation relative to sedentary individuals. The slight decrease in hematocrit by training is brought about by an increased plasma volume (PV). The mechanisms that increase total red blood cell mass by training are not understood fully. Despite stimulated erythropoiesis, exercise can decrease the red blood cell mass by intravascular hemolysis mainly of senescent red blood cells, which is caused by mechanical rupture when red blood cells pass through capillaries in contracting muscles, and by compression of red cells e.g., in foot soles during running or in hand palms in weightlifters. Together, these adjustments cause a decrease in the average age of the population of circulating red blood cells in trained athletes. These younger red cells are characterized by improved oxygen release and deformability, both of which also improve tissue oxygen supply during exercise.

  5. Red blood cells in sports: effects of exercise and training on oxygen supply by red blood cells

    PubMed Central

    Mairbäurl, Heimo

    2013-01-01

    During exercise the cardiovascular system has to warrant substrate supply to working muscle. The main function of red blood cells in exercise is the transport of O2 from the lungs to the tissues and the delivery of metabolically produced CO2 to the lungs for expiration. Hemoglobin also contributes to the blood's buffering capacity, and ATP and NO release from red blood cells contributes to vasodilation and improved blood flow to working muscle. These functions require adequate amounts of red blood cells in circulation. Trained athletes, particularly in endurance sports, have a decreased hematocrit, which is sometimes called “sports anemia.” This is not anemia in a clinical sense, because athletes have in fact an increased total mass of red blood cells and hemoglobin in circulation relative to sedentary individuals. The slight decrease in hematocrit by training is brought about by an increased plasma volume (PV). The mechanisms that increase total red blood cell mass by training are not understood fully. Despite stimulated erythropoiesis, exercise can decrease the red blood cell mass by intravascular hemolysis mainly of senescent red blood cells, which is caused by mechanical rupture when red blood cells pass through capillaries in contracting muscles, and by compression of red cells e.g., in foot soles during running or in hand palms in weightlifters. Together, these adjustments cause a decrease in the average age of the population of circulating red blood cells in trained athletes. These younger red cells are characterized by improved oxygen release and deformability, both of which also improve tissue oxygen supply during exercise. PMID:24273518

  6. Red blood cell membrane fragments but not intact red blood cells promote calcium oxalate monohydrate crystal growth and aggregation.

    PubMed

    Chutipongtanate, Somchai; Thongboonkerd, Visith

    2010-08-01

    Cell membranes are thought to promote calcium oxalate kidney stone formation but to our knowledge the modulating effect of red blood cell membranes on calcium oxalate crystals has not been previously investigated. Thus, we examined the effects of red blood cell membrane fragments on calcium oxalate monohydrate and calcium oxalate dihydrate crystal growth and aggregation. Calcium oxalate monohydrate and calcium oxalate dihydrate crystals were treated with red blood cell membrane fragments or intact red blood cells from a healthy donor. Phase contrast microscopy was performed to evaluate crystal morphology and aggregation. We used ImageMaster 2D Platinum software to evaluate crystal size and spectrophotometric oxalate depletion assay to monitor crystal growth. Red blood cell membrane fragments had significant promoting activity on calcium oxalate monohydrate crystal growth with an approximately 75% increase in size and aggregation with an approximately 2.5-fold increase in aggregate number compared to the control without membrane fragments or cells. Approximately 50% of calcium oxalate monohydrate crystals were adhered by red blood cell membrane fragments. Intact red blood cells had no significant effect on calcium oxalate monohydrate crystal growth or aggregation but they could transform calcium oxalate monohydrate to calcium oxalate dihydrate crystals. Red blood cell membrane fragments and intact red blood cells had no effect on calcium oxalate dihydrate crystals. The promoting activity of red blood cell membrane fragments on calcium oxalate monohydrate crystal growth was successfully confirmed by spectrophotometric oxalate depletion assay. To our knowledge our data provide the first direct evidence that red blood cell membrane fragments are a promoting factor for calcium oxalate monohydrate crystal growth and aggregation. Thus, they may aggravate calcium oxalate stone formation. Copyright (c) 2010 American Urological Association Education and Research, Inc

  7. Squeezing red blood cells on an optical waveguide to monitor cell deformability during blood storage.

    PubMed

    Ahluwalia, Balpreet Singh; McCourt, Peter; Oteiza, Ana; Wilkinson, James S; Huser, Thomas R; Hellesø, Olav Gaute

    2015-01-07

    Red blood cells squeeze through micro-capillaries as part of blood circulation in the body. The deformability of red blood cells is thus critical for blood circulation. In this work, we report a method to optically squeeze red blood cells using the evanescent field present on top of a planar waveguide chip. The optical forces from a narrow waveguide are used to squeeze red blood cells to a size comparable to the waveguide width. Optical forces and pressure distributions on the cells are numerically computed to explain the squeezing process. The proposed technique is used to quantify the loss of blood deformability that occurs during blood storage lesion. Squeezing red blood cells using waveguides is a sensitive technique and works simultaneously on several cells, making the method suitable for monitoring stored blood.

  8. Osmotic parameters of red blood cells from umbilical cord blood.

    PubMed

    Zhurova, Mariia; McGann, Locksley E; Acker, Jason P

    2014-06-01

    The transfusion of red blood cells from umbilical cord blood (cord RBCs) is gathering significant interest for the treatment of fetal and neonatal anemia, due to its high content of fetal hemoglobin as well as numerous other potential benefits to fetuses and neonates. However, in order to establish a stable supply of cord RBCs for clinical use, a cryopreservation method must be developed. This, in turn, requires knowledge of the osmotic parameters of cord RBCs. Thus, the objective of this study was to characterize the osmotic parameters of cord RBCs: osmotically inactive fraction (b), hydraulic conductivity (Lp), permeability to cryoprotectant glycerol (Pglycerol), and corresponding Arrhenius activation energies (Ea). For Lp and Pglycerol determination, RBCs were analyzed using a stopped-flow system to monitor osmotically-induced RBC volume changes via intrinsic RBC hemoglobin fluorescence. Lp and Pglycerol were characterized at 4°C, 20°C, and 35°C using Jacobs and Stewart equations with the Ea calculated from the Arrhenius plot. Results indicate that cord RBCs have a larger osmotically inactive fraction compared to adult RBCs. Hydraulic conductivity and osmotic permeability to glycerol of cord RBCs differed compared to those of adult RBCs with the differences dependent on experimental conditions, such as temperature and osmolality. Compared to adult RBCs, cord RBCs had a higher Ea for Lp and a lower Ea for Pglycerol. This information regarding osmotic parameters will be used in future work to develop a protocol for cryopreserving cord RBCs.

  9. Light scattering by aggregated red blood cells

    NASA Astrophysics Data System (ADS)

    Tsinopoulos, Stephanos V.; Sellountos, Euripides J.; Polyzos, Demosthenes

    2002-03-01

    In low flow rates, red blood cells (RBCs) fasten together along their axis of symmetry and form a so-called rouleaux. The scattering of He-Ne laser light by a rouleau consisting of n (2 less-than-or-equal n less-than-or-equal 8) average-sized RBCs is investigated. The interaction problem is treated numerically by means of an advanced axisymmetric boundary element--fast Fourier transform methodology. The scattering problem of one RBC was solved first, and the results showed that the influence of the RBC's membrane on the scattering patterns is negligible. Thus the rouleau is modeled as an axisymmetric, homogeneous, low-contrast dielectric cylinder, on the surface of which appears, owing to aggregated RBCs, a periodic roughness along the direction of symmetry. The direction of the incident laser light is considered to be perpendicular to the scatterer's axis of symmetry. The differential scattering cross sections in both perpendicular and parallel scattering planes and for all the scattering angles are calculated and presented in detail.

  10. Developmental Plasticity of Red Blood Cell Homeostasis

    PubMed Central

    Golub, Mari S.; Hogrefe, Casey E.; Malka, Roy; Higgins, John M.

    2014-01-01

    Most human physiologic set points like body temperature are tightly regulated and show little variation between healthy individuals. Red blood cell (RBC) characteristics such as hematocrit (HCT) and mean cell volume (MCV) are stable within individuals but can vary by 20% from one healthy person to the next. The mechanisms for the majority of this inter-individual variation are unknown and do not appear to involve common genetic variation. Here we show that environmental conditions present during development, namely in utero iron availability, can exert long-term influence on a set point related to the RBC life cycle. In a controlled study of rhesus monkeys and a retrospective study of humans, we use a mathematical model of in vivo RBC population dynamics to show that in utero iron deficiency is associated with a lowered threshold for RBC clearance and turnover. This in utero effect is plastic, persisting at least two years after birth and after the cessation of iron deficiency. Our study reports a rare instance of developmental plasticity in the human hematologic systems and also shows how mathematical modeling can be used to identify cellular mechanisms involved in the adaptive control of homeostatic set points. PMID:24415575

  11. Polypeptide multilayer nanofilm artificial red blood cells.

    PubMed

    Palath, Naveen; Bhad, Sujaykumar; Montazeri, Reza; Guidry, Christopher A; Haynie, Donald T

    2007-04-01

    Reliable encapsulation of hemoglobin (Hb) within polypeptide multilayer nanofilms has been achieved by a template-based approach, and protein functionality has been demonstrated postencapsulation. The method is general in scope and could be useful for many other encapsulants. Met-Hb was adsorbed onto 5 microm-diameter CaCO3 microparticles, and the Hb-coated particles were encapsulated within a multilayer nanofilm of poly(L-glutamic acid) (PLGA) and poly(L-lysine) (PLL) by layer-by-layer assembly. The CaCO3 templates were then dissolved within the PLGA/PLL nanofilms by addition of ethylenediaminetetraacetic acid. Encapsulation of Hb was proved by fluorescence microscopy, the pH-dependence of retention of Hb was determined by visible wavelength absorbance, and conversion of the encapsulated met-Hb to deoxy-Hb and oxy-Hb was demonstrated by spectroscopic analysis of the Soret absorption peak under various conditions. It thus has been shown that control of Hb oxygenation within polypeptide multilayer nanofilm artificial cells is possible, and that Hb thus encapsulated can bind, release, and subsequently rebind molecular oxygen. This work therefore represents an advance in the development of polypeptide multilayer film artificial red blood cells. (c) 2006 Wiley Periodicals, Inc.

  12. Red blood cell vesiculation in hereditary hemolytic anemia

    PubMed Central

    Alaarg, Amr; Schiffelers, Raymond M.; van Solinge, Wouter W.; van Wijk, Richard

    2013-01-01

    Hereditary hemolytic anemia encompasses a heterogeneous group of anemias characterized by decreased red blood cell survival because of inherited membrane, enzyme, or hemoglobin disorders. Affected red blood cells are more fragile, less deformable, and more susceptible to shear stress and oxidative damage, and show increased vesiculation. Red blood cells, as essentially all cells, constitutively release phospholipid extracellular vesicles in vivo and in vitro in a process known as vesiculation. These extracellular vesicles comprise a heterogeneous group of vesicles of different sizes and intracellular origins. They are described in literature as exosomes if they originate from multi-vesicular bodies, or as microvesicles when formed by a one-step budding process directly from the plasma membrane. Extracellular vesicles contain a multitude of bioactive molecules that are implicated in intercellular communication and in different biological and pathophysiological processes. Mature red blood cells release in principle only microvesicles. In hereditary hemolytic anemias, the underlying molecular defect affects and determines red blood cell vesiculation, resulting in shedding microvesicles of different compositions and concentrations. Despite extensive research into red blood cell biochemistry and physiology, little is known about red cell deformability and vesiculation in hereditary hemolytic anemias, and the associated pathophysiological role is incompletely assessed. In this review, we discuss recent progress in understanding extracellular vesicles biology, with focus on red blood cell vesiculation. Also, we review recent scientific findings on the molecular defects of hereditary hemolytic anemias, and their correlation with red blood cell deformability and vesiculation. Integrating bio-analytical findings on abnormalities of red blood cells and their microvesicles will be critical for a better understanding of the pathophysiology of hereditary hemolytic anemias. PMID

  13. Red blood cell vesiculation in hereditary hemolytic anemia.

    PubMed

    Alaarg, Amr; Schiffelers, Raymond M; van Solinge, Wouter W; van Wijk, Richard

    2013-12-13

    Hereditary hemolytic anemia encompasses a heterogeneous group of anemias characterized by decreased red blood cell survival because of inherited membrane, enzyme, or hemoglobin disorders. Affected red blood cells are more fragile, less deformable, and more susceptible to shear stress and oxidative damage, and show increased vesiculation. Red blood cells, as essentially all cells, constitutively release phospholipid extracellular vesicles in vivo and in vitro in a process known as vesiculation. These extracellular vesicles comprise a heterogeneous group of vesicles of different sizes and intracellular origins. They are described in literature as exosomes if they originate from multi-vesicular bodies, or as microvesicles when formed by a one-step budding process directly from the plasma membrane. Extracellular vesicles contain a multitude of bioactive molecules that are implicated in intercellular communication and in different biological and pathophysiological processes. Mature red blood cells release in principle only microvesicles. In hereditary hemolytic anemias, the underlying molecular defect affects and determines red blood cell vesiculation, resulting in shedding microvesicles of different compositions and concentrations. Despite extensive research into red blood cell biochemistry and physiology, little is known about red cell deformability and vesiculation in hereditary hemolytic anemias, and the associated pathophysiological role is incompletely assessed. In this review, we discuss recent progress in understanding extracellular vesicles biology, with focus on red blood cell vesiculation. Also, we review recent scientific findings on the molecular defects of hereditary hemolytic anemias, and their correlation with red blood cell deformability and vesiculation. Integrating bio-analytical findings on abnormalities of red blood cells and their microvesicles will be critical for a better understanding of the pathophysiology of hereditary hemolytic anemias.

  14. Effects of helicopter transport on red blood cell components

    PubMed Central

    Otani, Taiichi; Oki, Ken-ichi; Akino, Mitsuaki; Tamura, Satoru; Naito, Yuki; Homma, Chihiro; Ikeda, Hisami; Sumita, Shinzou

    2012-01-01

    Background There are no reported studies on whether a helicopter flight affects the quality and shelf-life of red blood cells stored in mannitol-adenine-phosphate. Materials and methods Seven days after donation, five aliquots of red blood cells from five donors were packed into an SS-BOX-110 container which can maintain the temperature inside the container between 2 °C and 6 °C with two frozen coolants. The temperature of an included dummy blood bag was monitored. After the box had been transported in a helicopter for 4 hours, the red blood cells were stored again and their quality evaluated at day 7 (just after the flight), 14, 21 and 42 after donation. Red blood cell quality was evaluated by measuring adenosine triphosphate, 2,3-diphosphoglycerate, and supernatant potassium, as well as haematocrit, intracellular pH, glucose, supernatant haemoglobin, and haemolysis rate at the various time points. Results During the experiment the recorded temperature remained between 2 and 6 °C. All data from the red blood cells that had undergone helicopter transportation were the same as those from a control group of red blood cell samples 7 (just after the flight), 14, 21, and 42 days after the donation. Only supernatant Hb and haemolysis rate 42 days after the donation were slightly increased in the helicopter-transported group of red blood cell samples. All other parameters at 42 days after donation were the same in the two groups of red blood cells. Discussion These results suggest that red blood cells stored in mannitol-adenine-phosphate are not significantly affected by helicopter transportation. The differences in haemolysis by the end of storage were small and probably not of clinical significance. PMID:22153688

  15. Effects of helicopter transport on red blood cell components.

    PubMed

    Otani, Taiichi; Oki, Ken-ichi; Akino, Mitsuaki; Tamura, Satoru; Naito, Yuki; Homma, Chihiro; Ikeda, Hisami; Sumita, Shinzou

    2012-01-01

    There are no reported studies on whether a helicopter flight affects the quality and shelf-life of red blood cells stored in mannitol-adenine-phosphate. Seven days after donation, five aliquots of red blood cells from five donors were packed into an SS-BOX-110 container which can maintain the temperature inside the container between 2 °C and 6 °C with two frozen coolants. The temperature of an included dummy blood bag was monitored. After the box had been transported in a helicopter for 4 hours, the red blood cells were stored again and their quality evaluated at day 7 (just after the flight), 14, 21 and 42 after donation. Red blood cell quality was evaluated by measuring adenosine triphosphate, 2,3-diphosphoglycerate, and supernatant potassium, as well as haematocrit, intracellular pH, glucose, supernatant haemoglobin, and haemolysis rate at the various time points. During the experiment the recorded temperature remained between 2 and 6 °C. All data from the red blood cells that had undergone helicopter transportation were the same as those from a control group of red blood cell samples 7 (just after the flight), 14, 21, and 42 days after the donation. Only supernatant Hb and haemolysis rate 42 days after the donation were slightly increased in the helicopter-transported group of red blood cell samples. All other parameters at 42 days after donation were the same in the two groups of red blood cells. These results suggest that red blood cells stored in mannitol-adenine-phosphate are not significantly affected by helicopter transportation. The differences in haemolysis by the end of storage were small and probably not of clinical significance.

  16. Born approximation model for light scattering by red blood cells.

    PubMed

    Lim, Joonoh; Ding, Huafeng; Mir, Mustafa; Zhu, Ruoyu; Tangella, Krishnarao; Popescu, Gabriel

    2011-10-01

    The primary role of a red blood cell (RBC) is delivering oxygen throughout our body. Abnormalities of this basic function lead to anemia and are caused by numerous diseases such as malaria and sickle cell anemia. As prompt and inexpensive tests for blood screening are in demand, we have developed a faster and reliable way to measure morphological parameters associated with the structure of red blood cells and the size distribution of the cells in a whole blood smear. Modeling the RBC shape under Born approximation, we are able to determine parameters of clinical relevance, such as the diameter, thickness and dimple size. From a measured quantitative phase image of a blood smear, we can determine the average and standard deviation of the red blood cell volume simultaneously, i.e., without analyzing each cell individually. This approach may open the door for a new generation of label-free, high-throughput blood testing.

  17. [Regularity of sugar-uptake in human red blood cells].

    PubMed

    Quan, Guo-Bo; Lü, Cui-Cui; Liu, Min-Xia; Hu, Wen-Bo; Wang, Yan; Han, Ying

    2006-06-01

    Lyophilization of human red blood cells has important significance in clinical application. Some sugars, especially trehalose, can be more tolerant of some organism or cells to dry environments, But, how to bring sugars into cells is a challenge. This study was aimed to investigate the regularity of sugar-uptake in human red blood cells. The absorption rate of trehalose and glucose in red blood cells, free hemoglobin level and erythrocyte deformation index were determined at different incubation temperature (4, 25 and 37 degrees C), different sugar concentration (0, 0.2, 0.4, 0.6, 0.8 and 1 mol/L) and different incubation time (1, 3, 5, 7 and 9 hours). The results showed that with increase of temperature and extracellular sugar concentration, the uptake of sugar in red blood cells also increased, the intracellular trehalose and glucose concentrations were over 30 mmol/L and 40 mmol/L respectively. The effects of incubation time on uptake of trehalose and glucose were different. With prolonging of incubation time, the uptake of trehalose showed firstly increase and then decrease, however, the uptake of glucose showed a constant increase. But the loading process had side-effect on free hemoglobin and maximum deformation index (MAXDI) of red blood cells, especially for trehalose, which mainly come from high osmotic pressure. It is concluded that the uptake of sugars in red blood cells is closely dependent on incubation temperature, extracellular sugar concentration and incubation time. In certain condition, the efficiency of sugar uptake is very high, but this process also damages red blood cells so as to affect the application of sugars in lyophilization of red blood cells. The research in the future should focus on how to deal with the relation between cell injury and uptake efficiency of sugar in red blood cells.

  18. Technetium-99m-labeled red blood cell imaging

    SciTech Connect

    Front, D.; Israel, O.; Groshar, D.; Weininger, J.

    1984-07-01

    Red blood cells labeled with 99mTc constitute a suitable intravascular agent for imaging of vascular abnormalities. Hemangiomas are characterized by low perfusion and a high blood pool. This ''perfusion blood-pool mismatch,'' not encountered in other lesions, may help in the specific diagnosis of this tumor. This is particularly so in cavernous hemangiomas of the liver where three-phase 99mTc-labeled red blood cell scintigraphy should precede liver biopsy. Red cell scintigraphy also is useful for establishing the vascular nature of hemangiomas of the head and neck and the skin and for diagnosis of venous occlusion. Heat-damaged red blood cells provide a specific spleen imaging agent. This should be used when patients with suspected splenic pathology have equivocal colloid scintigraphy.

  19. Kit for the selective labeling of red blood cells in whole blood with [sup 99]Tc

    DOEpatents

    Srivastava, S.C.; Babich, J.W.; Straub, R.; Richards, P.

    1992-05-26

    Disclosed herein are a method and kit for the preparation of [sup 99m]Tc labeled red blood cells using whole blood in a closed sterile system containing stannous tin in a form such that it will enter the red blood cells and be available therein for reduction of technetium. No Drawings

  20. Kit for the selective labeling of red blood cells in whole blood with .sup.9 TC

    DOEpatents

    Srivastava, Suresh C.; Babich, John W.; Straub, Rita; Richards, Powell

    1992-01-01

    Disclosed herein are a method and kit for the preparation of .sup.99m Tc labeled red blood cells using whole blood in a closed sterile system containing stannous tin in a form such that it will enter the red blood cells and be available therein for reduction of technetium.

  1. [Effects of infusion media on human red blood cell morphology].

    PubMed

    Burova, O O; Gusev, A A; Petrikov, S S; Gusev, S A; Basyreva, L Iu

    2006-01-01

    The effect of various infusion media on the structure of human red blood cells was evaluated in vitro and in vivo. The in vitro experiments used 10% sodium chloride (NaCl) solution, 10% glucose solution, 20% albumin solution, Rheopolyglucin, HyperHAES solution (18 g of NaCl in combination with 60 g of hydroxyethylstarch (HES), 200/0.5), Voluven (HES 130/0.4/9:1), and a combination of hypertensive NaCl solution and Rheopolyglucin. The morphofunctional response of red blood cells was studied in the clinical setting when 6% Voluven solution (HES 130/0.4/ 9:1) and hypertensive NaCl and glucose solutions were used. It was established that 10% NaCl solution caused considerable changes in the morphology of red blood cells both in the experiment and in patients with severe brain injury. The magnitude of structural changes increased as blood NaCl concentrations became higher. 10% glucose solution, Voluven, Rheopolyglucin, and albumin did not virtually affect the structure of red blood cells. Infusion of Voluven (500 ml of 6% solution for 40 minutes) induced no changes in the morphology of red blood cells in the clinical setting. Among the test solutions used to correct intracranial hypertension (HyperHAES, 10% NaCl, a combination of rheopolyglucin and 10% NaCl), HyperHAES exerted the least effect on the morphology of red blood cells.

  2. Models for the Red Blood Cell Lifespan

    PubMed Central

    Shrestha, Rajiv P.; Horowitz, Joseph; Hollot, Christopher V.; Germain, Michael J.; Widness, John A.; Mock, Donald M.; Veng-Pedersen, Peter; Chait, Yossi

    2016-01-01

    The lifespan of red blood cells (RBCs) plays an important role in the study and interpretation of various clinical conditions. Yet, confusion about the meanings of fundamental terms related to cell survival and their quantification still exists in the literature. To address these issues, we started from a compartmental model of RBC populations based on an arbitrary full lifespan distribution, carefully defined the residual lifespan, current age, and excess lifespan of the RBC population, and then derived the distributions of these parameters. For a set of residual survival data from biotin-labeled RBCs, we fit models based on Weibull, gamma, and lognormal distributions, using nonlinear mixed effects (NLME) modeling and parametric bootstrapping. From the estimated Weibull, gamma, and lognormal parameters we computed the respective population mean full lifespans (95% confidence interval): 115.60 (109.17–121.66), 116.71 (110.81–122.51), and 116.79 (111.23–122.75) days together with the standard deviations of the full lifespans: 24.77 (20.82–28.81), 24.30 (20.53–28.33), and 24.19 (20.43–27.73). We then estimated the 95th percentiles of the lifespan distributions (a surrogate for the maximum lifespan): 153.95 (150.02–158.36), 159.51 (155.09–164.00), and 160.40 (156.00–165.58) days, the mean current ages (or the mean residual lifespans): 60.45 (58.18–62.85), 60.82 (58.77–63.33), and 57.26 (54.33–60.61) days, and the residual half-lives: 57.97 (54.96–60.90), 58.36 (55.45–61.26), and 58.40 (55.62–61.37) days, for the Weibull, gamma, and lognormal models respectively. Corresponding estimates were obtained for the individual subjects. The three models provide equally excellent goodness-of-fit, reliable estimation, and physiologically plausible values of the directly interpretable RBC survival parameters. PMID:27039311

  3. Models for the red blood cell lifespan.

    PubMed

    Shrestha, Rajiv P; Horowitz, Joseph; Hollot, Christopher V; Germain, Michael J; Widness, John A; Mock, Donald M; Veng-Pedersen, Peter; Chait, Yossi

    2016-06-01

    The lifespan of red blood cells (RBCs) plays an important role in the study and interpretation of various clinical conditions. Yet, confusion about the meanings of fundamental terms related to cell survival and their quantification still exists in the literature. To address these issues, we started from a compartmental model of RBC populations based on an arbitrary full lifespan distribution, carefully defined the residual lifespan, current age, and excess lifespan of the RBC population, and then derived the distributions of these parameters. For a set of residual survival data from biotin-labeled RBCs, we fit models based on Weibull, gamma, and lognormal distributions, using nonlinear mixed effects modeling and parametric bootstrapping. From the estimated Weibull, gamma, and lognormal parameters we computed the respective population mean full lifespans (95 % confidence interval): 115.60 (109.17-121.66), 116.71 (110.81-122.51), and 116.79 (111.23-122.75) days together with the standard deviations of the full lifespans: 24.77 (20.82-28.81), 24.30 (20.53-28.33), and 24.19 (20.43-27.73). We then estimated the 95th percentiles of the lifespan distributions (a surrogate for the maximum lifespan): 153.95 (150.02-158.36), 159.51 (155.09-164.00), and 160.40 (156.00-165.58) days, the mean current ages (or the mean residual lifespans): 60.45 (58.18-62.85), 60.82 (58.77-63.33), and 57.26 (54.33-60.61) days, and the residual half-lives: 57.97 (54.96-60.90), 58.36 (55.45-61.26), and 58.40 (55.62-61.37) days, for the Weibull, gamma, and lognormal models respectively. Corresponding estimates were obtained for the individual subjects. The three models provide equally excellent goodness-of-fit, reliable estimation, and physiologically plausible values of the directly interpretable RBC survival parameters.

  4. Control of red blood cell mass during spaceflight

    NASA Technical Reports Server (NTRS)

    Lane, H. W.; Alfrey, C. P.; Driscoll, T. B.; Smith, S. M.; Nyquist, L. E.

    1996-01-01

    Data are reviewed from twenty-two astronauts from seven space missions in a study of red blood cell mass. The data show that decreased red cell mass in all astronauts exposed to space for more than nine days, although the actual dynamics of mass changes varies with flight duration. Possible mechanisms for these changes, including alterations in erythropoietin levels, are discussed.

  5. Control of red blood cell mass during spaceflight

    NASA Technical Reports Server (NTRS)

    Lane, H. W.; Alfrey, C. P.; Driscoll, T. B.; Smith, S. M.; Nyquist, L. E.

    1996-01-01

    Data are reviewed from twenty-two astronauts from seven space missions in a study of red blood cell mass. The data show that decreased red cell mass in all astronauts exposed to space for more than nine days, although the actual dynamics of mass changes varies with flight duration. Possible mechanisms for these changes, including alterations in erythropoietin levels, are discussed.

  6. Malaria and Human Red Blood Cells

    PubMed Central

    Mohandas, Narla; An, Xiuli

    2013-01-01

    Invasion by the malaria parasite, P. falciparum brings about extensive changes in the host red cells. These include loss of the normal discoid shape, increased rigidity of the membrane, elevated permeability to a wide variety of ionic and other species, and increased adhesiveness, most notably to endothelial surfaces. These effects facilitate survival of the parasite within the host cell and tend to increase the virulence of disease that include cerebral malaria and anemia. Numerous proteins secreted by the internalized parasite and interaction with red cell membrane proteins are responsible for the changes occurring to the host cell. Anemia a serious clinical manifestation of malaria is due to increased destruction of both infected and uninfected red cells due to membrane alterations, as well as ineffective erythropoiesis. There is very good evidence that various red cell disorders including hemoglobinopathies and hereditary ovalocytosis decrease the virulence of disease following parasite infection. A number of mechanism(s) are likely responsible for the protective effect of various red cell abnormalities including decreased invasion, impaired intraerythrocytic development of the parasites and altered interaction between exported parasite proteins and the red cell membrane skeleton. PMID:22965173

  7. Malaria and human red blood cells.

    PubMed

    Mohandas, Narla; An, Xiuli

    2012-11-01

    Invasion by the malaria parasite, Plasmodium falciparum, brings about extensive changes in the host red cells. These include loss of the normal discoid shape, increased rigidity of the membrane, elevated permeability to a wide variety of ionic and other species and increased adhesiveness, most notably to endothelial surfaces. These effects facilitate survival of the parasite within the host cell and tend to increase the virulence of disease that includes cerebral malaria and anemia. Numerous proteins secreted by the internalized parasite and interacting with red cell membrane proteins are responsible for the changes occurring to the host cell. Anemia, a serious clinical manifestation of malaria, is due to increased destruction of both infected and uninfected red cells due to membrane alterations, as well as ineffective erythropoiesis. There is very good evidence that various red cell disorders including hemoglobinopathies and hereditary ovalocytosis decrease the virulence of disease following parasite infection. A number of mechanism(s) are likely responsible for the protective effect of various red cell abnormalities including decreased invasion, impaired intraerythrocytic development of the parasites and altered interaction between exported parasite proteins and the red cell membrane skeleton.

  8. Quantification of red blood cells using atomic force microscopy.

    PubMed

    O'Reilly, M; McDonnell, L; O'Mullane, J

    2001-01-01

    For humans the sizes and shapes of their red blood cells are important indicators of well being. In this study, the feasibility of using the atomic force microscope (AFM) to provide the sizes and shapes of red blood cells has been investigated. An immobilisation procedure has been developed that enabled red blood cells to be reliably imaged by contact AFM in air. The shapes of the red blood cells were readily apparent in the AFM images. Various cell quantification parameters were investigated, including thickness, width, surface area and volume. Excellent correlation was found between the AFM-derived immobilised mean cell volume (IMCV) parameter and the mean cell volume (MCV) parameter used in current haematological practice. The correlation between MCV and IMCV values has validated the immobilisation procedure by demonstrating that the significant cell shrinkage that occurs during immobilisation and drying does not introduce quantification artifacts. Reliable IMCV values were obtained by quantifying 100 red blood cells and this typically required 3-5 AFM images of 100 microm x 100 microm area. This work has demonstrated that the AFM can provide in a single test the red blood cell size and shape data needed in the assessment of human health.

  9. Hypoalbuminemia causes high blood viscosity by increasing red cell lysophosphatidylcholine.

    PubMed

    Joles, J A; Willekes-Koolschijn, N; Koomans, H A

    1997-09-01

    Albumin deficiency is accompanied by a reduction in red cell deformability and blood hyperviscosity. Albumin deficiency increases plasma fibrinogen and triglyceride levels and may alter red cell membrane lipid composition. These options, which could all contribute to reduced red cell deformability (RCD) and hyperviscosity, were studied in the Nagase analbuminemic rat (NAR), a mutant Sprague Dawley rat (CON), characterized by normal total protein levels, with an absolute deficiency of albumin, but elevated levels of non-albumin proteins and hyperlipidemia. Plasma protein-binding of the polar phopholipid lysophosphatidylcholine (LPC) was markedly decreased. LPC comprised only 26 +/- 1% of total plasma phospholipids as compared to 42 +/- 2% in CON. NAR red cells in CON plasma had a viscosity that was similar to CON red cells in CON plasma. Conversely, CON red cells in NAR plasma show an increased viscosity as compared to CON red cells in CON plasma. The maximum deformation index of both NAR and CON red cells was markedly decreased in NAR plasma as compared to either NAR or CON cells in CON plasma (0.04 +/- 0.03 and 0.02 +/- 0.02 vs. 0.22 +/- 0.06 and 0.15 +/- 0.04, respectively; P < 0.05). Thus, plasma composition causes hyperviscosity and reduced RCD in NAR. Fibrinogen is not responsible since red cells in serum and red cells in plasma had a similar viscosity and differences in viscosity and RCD between NAR and CON were maintained. Plasma triglycerides are also not responsible since the viscosity of red cells in serum with a 50% reduction in triglycerides was not reduced. LPC levels in red cells were increased in NAR (8.7 +/- 0.2 vs. 5.5 +/- 0.3% of total phospholipids; P < 0.01). Adding albumin to NAR blood dose-dependently decreased whole blood viscosity, despite marked increases in plasma viscosity, and increased RCD of NAR cells (from 0.04 +/- 0.03 to 0.21 +/- 0.01; P < 0.05). There was also some effect on CON RCD of similar albumin addition to CON blood (from 0

  10. Modification of red blood cells for laboratory quality control use.

    PubMed

    Henry, Stephen M

    2009-11-01

    This review describes the current state-of-the-art with respect to the modification of red blood cells for creating quality controls for use in immunohaematology. The author has identified five technologies able to create modified red blood cells potentially suitable for use in quality control. Two of the technologies use enzymes, glycosidases or glycosyltransferases, to modify red blood cells and create ABO quality control cells. A third technology uses polyethylene glycol to reduce antigen expression by masking epitopes, whereas a fourth technology is speculative and involves the in-vitro generation of genetically modified erythroid cells. None of these four technologies are in routine use to make commercially available quality controls. A fifth commercially available technology creates quality controls by adding synthetic blood group A and B antigens (FSLs) to group O red blood cells, creating what are referred to as 'kodecytes'. This technology is also being used to add blood group peptides onto red cells for use in the future in a range of diagnostic applications. Transducing cell-derived erythroid populations with blood group encoding or silencing vectors, and the use of FSLs to create kodecytes, are two technologies with the potential to provide quality controls for laboratory use.

  11. Computational Biomechanics of Human Red Blood Cells in Hematological Disorders.

    PubMed

    Li, Xuejin; Li, He; Chang, Hung-Yu; Lykotrafitis, George; Em Karniadakis, George

    2017-02-01

    We review recent advances in multiscale modeling of the biomechanical characteristics of red blood cells (RBCs) in hematological diseases, and their relevance to the structure and dynamics of defective RBCs. We highlight examples of successful simulations of blood disorders including malaria and other hereditary disorders, such as sickle-cell anemia, spherocytosis, and elliptocytosis.

  12. Red blood cell aggregate flux in a bifurcating microchannel.

    PubMed

    Kaliviotis, E; Pasias, D; Sherwood, J M; Balabani, S

    2017-10-01

    Red blood cell aggregation plays a key role in microcirculatory flows, however, little is known about the transport characteristics of red blood cell aggregates in branching geometries. This work reports on the fluxes of red blood cell aggregates of various sizes in a T-shaped microchannel, aiming to clarify the effects of different flow conditions in the outlet branches of the channel. Image analysis techniques, were utilised, and moderately aggregating human red blood cell suspensions were tested in symmetric (∼50-50%) and asymmetric flow splits through the two outlet (daughter) branches. The results revealed that the flux decreases with aggregate size in the inlet (parent) and daughter branches, mainly due to the fact that the number of larger structures is significantly smaller than that of smaller structures. However, when the flux in the daughter branches is examined relative to the aggregate size flux in the parent branch an increase with aggregate size is observed for a range of asymmetric flow splits. This increase is attributed to size distribution and local concentration changes in the daughter branches. The results show that the flow of larger aggregates is not suppressed downstream of a bifurcation, and that blood flow is maintained, for physiological levels of red blood cell aggregation. Copyright © 2017 IPEM. Published by Elsevier Ltd. All rights reserved.

  13. Red blood cell nitric oxide synthase modulates red blood cell deformability in sickle cell anemia.

    PubMed

    Mozar, Anaïs; Connes, Philippe; Collins, Bianca; Hardy-Dessources, Marie-Dominique; Romana, Marc; Lemonne, Nathalie; Bloch, Wilhelm; Grau, Marijke

    2016-11-04

    Sickle cell anemia (SCA) is an inherited red blood cells (RBC) disorder characterized by significantly decreased RBC deformability. The present study aimed to assess whether modulation of RBC Nitric Oxide Synthase (RBC-NOS) activation could affect RBC deformability in SCA.Blood of twenty-five SCA patients was treated for 1 hour at 37°C with Phosphate Buffered Saline (PBS) or PBS containing 1% of Dimethylsulfoxyde as control, L-arginine or N(5)-(1-Iminoethyl)-L-ornithine (L-NIO) to directly stimulate or inhibit RBC-NOS, insulin or wortmannin to indirectly stimulate or inhibit RBC-NOS through their effects on the PI3 Kinase/Akt pathway, and sodium nitroprusside (SNP) and 2-(4-Carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (cPTIO) as NO donor and NO scavenger, respectively. RBC deformability was measured by ektacytometry at 3 Pa.RBC deformability significantly increased after insulin treatment and significantly decreased after L-NIO and wortmannin incubation. The other conditions did not affect deformability. Significantly increased nitrotyrosine levels, a marker of enhanced free radical generation, were detected by immunohistochemistry in SNP and insulin treated samples.These data suggest that RBC deformability of SCA can be modulated by RBC-NOS activity but also that oxidative stress may impair effectiveness of RBC-NOS produced NO.

  14. Quantification of Depletion-Induced Adhesion of Red Blood Cells

    NASA Astrophysics Data System (ADS)

    Steffen, P.; Verdier, C.; Wagner, C.

    2013-01-01

    Red blood cells (RBCs) are known to form aggregates in the form of rouleaux due to the presence of plasma proteins under physiological conditions. The formation of rouleaux can also be induced in vitro by the addition of macromolecules to the RBC suspension. Current data on the adhesion strength between red blood cells in their natural discocyte shapes mostly originate from indirect measurements such as flow chamber experiments, but data is lacking at the single cell level. Here, we present measurements on the dextran-induced aggregation of red blood cells using atomic force microscopy-based single cell force spectroscopy. The effects of dextran concentration and molecular weight on the interaction energy of adhering RBCs were determined. The results on adhesion energy are in excellent agreement with a model based on the depletion effect and previous experimental studies. Furthermore, our method allowed to determine the adhesion force, a quantity that is needed in theoretical investigations on blood flow.

  15. Mechanisms linking red blood cell disorders and cardiovascular diseases.

    PubMed

    Mozos, Ioana

    2015-01-01

    The present paper aims to review the main pathophysiological links between red blood cell disorders and cardiovascular diseases, provides a brief description of the latest studies in this area, and considers implications for clinical practice and therapy. Anemia is associated with a special risk in proatherosclerotic conditions and heart disease and became a new therapeutic target. Guidelines must be updated for the management of patients with red blood cell disorders and cardiovascular diseases, and targets for hemoglobin level should be established. Risk scores in several cardiovascular diseases should include red blood cell count and RDW. Complete blood count and hemorheological parameters represent useful, inexpensive, widely available tools for the management and prognosis of patients with coronary heart disease, heart failure, hypertension, arrhythmias, and stroke. Hypoxia and iron accumulation cause the most important cardiovascular effects of sickle cell disease and thalassemia. Patients with congenital chronic hemolytic anemia undergoing splenectomy should be monitored, considering thromboembolic and cardiovascular risk.

  16. Quantification of depletion-induced adhesion of red blood cells.

    PubMed

    Steffen, P; Verdier, C; Wagner, C

    2013-01-04

    Red blood cells (RBCs) are known to form aggregates in the form of rouleaux due to the presence of plasma proteins under physiological conditions. The formation of rouleaux can also be induced in vitro by the addition of macromolecules to the RBC suspension. Current data on the adhesion strength between red blood cells in their natural discocyte shapes mostly originate from indirect measurements such as flow chamber experiments, but data is lacking at the single cell level. Here, we present measurements on the dextran-induced aggregation of red blood cells using atomic force microscopy-based single cell force spectroscopy. The effects of dextran concentration and molecular weight on the interaction energy of adhering RBCs were determined. The results on adhesion energy are in excellent agreement with a model based on the depletion effect and previous experimental studies. Furthermore, our method allowed to determine the adhesion force, a quantity that is needed in theoretical investigations on blood flow.

  17. Mechanisms Linking Red Blood Cell Disorders and Cardiovascular Diseases

    PubMed Central

    2015-01-01

    The present paper aims to review the main pathophysiological links between red blood cell disorders and cardiovascular diseases, provides a brief description of the latest studies in this area, and considers implications for clinical practice and therapy. Anemia is associated with a special risk in proatherosclerotic conditions and heart disease and became a new therapeutic target. Guidelines must be updated for the management of patients with red blood cell disorders and cardiovascular diseases, and targets for hemoglobin level should be established. Risk scores in several cardiovascular diseases should include red blood cell count and RDW. Complete blood count and hemorheological parameters represent useful, inexpensive, widely available tools for the management and prognosis of patients with coronary heart disease, heart failure, hypertension, arrhythmias, and stroke. Hypoxia and iron accumulation cause the most important cardiovascular effects of sickle cell disease and thalassemia. Patients with congenital chronic hemolytic anemia undergoing splenectomy should be monitored, considering thromboembolic and cardiovascular risk. PMID:25710019

  18. In vivo red blood cell compatibility testing using indium-113m tropolone-labeled red blood cells

    SciTech Connect

    Morrissey, G.J.; Gravelle, D.; Dietz, G.; Driedger, A.A.; King, M.; Cradduck, T.D.

    1988-05-01

    In vivo radionuclide crossmatch is a method for identifying compatible blood for transfusion when allo- or autoantibodies preclude the use of conventional crossmatching techniques. A technique for labeling small volumes of donor red blood cells with (/sup 113m/In)tropolone is reported. The use of /sup 113m/In minimizes the accumulation of background radioactivity and the radiation dose especially so when multiple crossmatches are performed. Labeling red cells with (/sup 113m/In)tropolone is faster and easier to perform than with other radionuclides. Consistently high labeling efficiencies are obtained and minimal /sup 113m/In activity elutes from the labeled red blood cells. A case study involving 22 crossmatches is presented to demonstrate the technique. The radiation dose equivalent from /sup 113m/In is significantly less than with other radionuclides that may be used to label red cells.

  19. Freeze-Dried Human Red Blood Cells

    DTIC Science & Technology

    1992-01-15

    outlined in our November progress report had been successfully used to repair damage incurred by RBC during hypotonic lysis ( referencesl and 2). The...reconstitution. Figures IA-IF show the osmotic deformability profiles of our thawed red cell preparation. Note the well defined hypotonic and hypertonic...upon rehydration. The osmotic deformability profiles of the reconstituted lyophilized cells are also nearly normal with well defined hypotonic and

  20. Cryopreservation of Autologous Blood (Red Blood Cells, Platelets and Plasma)

    NASA Astrophysics Data System (ADS)

    Ebine, Kunio

    Prevention of post-transfusion hepatitis is still a problem in cardiovascular surgery. We initiated the cryopreservation of autologous blood for the transfusion in elective cardiovascular surgery since 1981. This study includes 152 surgical cases in which autologous frozen, allogeneic frozen, and/or allogeneic non-frozen blood were used. In the 152 surgical cases, there were 69 cases in which autologous blood only (Group I) was used; 12 cases with autologous and allogeneic frozen blood (Group II); 46 cases with autologous and allgeneic frozen plus allogeneic non-frozen blood (Group III); and 25 cases with allogeneic frozen plus allogeneic non-frozen blood (Group IV). No hepatitis developed in Groups I (0%) and II (0%), but there was positive hepatitis in Groups III (4.3%) and IV (8.0%) . In 357 cases of those who underwent surgery with allogeneic non-frozen whole blood during the same period, the incidence rate of hepatitis was 13.7% (49/357). Patients awaiting elective surgery can store their own blood in the frozen state. Patients who undergo surgery with the cryoautotransfusion will not produce any infections or immunologic reactions as opposed to those who undergo surgery with the allogeneic non-frozen blood.

  1. Spatial Distributions of Red Blood Cells Significantly Alter Local Haemodynamics

    PubMed Central

    Sherwood, Joseph M.; Holmes, David; Kaliviotis, Efstathios; Balabani, Stavroula

    2014-01-01

    Although bulk changes in red blood cell concentration between vessels have been well characterised, local distributions are generally overlooked. Red blood cells aggregate, deform and migrate within vessels, forming heterogeneous distributions which have considerable effect on local haemodynamics. The present study reports data on the local distribution of human red blood cells in a sequentially bifurcating microchannel, representing the branching geometry of the microvasculature. Imaging methodologies with simple extrapolations are used to infer three dimensional, time-averaged velocity and haematocrit distributions under a range of flow conditions. Strong correlation between the bluntness of the velocity and haematocrit profiles in the parent branch of the geometry is observed and red blood cell aggregation has a notable effect on the observed trends. The two branches of the first bifurcation show similar characteristics in terms of the shapes of the profiles and the extent of plasma skimming, despite the difference in geometric configuration. In the second bifurcation, considerable asymmetry between the branches in the plasma skimming relationship is observed, and elucidated by considering individual haematocrit profiles. The results of the study highlight the importance of considering local haematocrit distributions in the analysis of blood flow and could lead to more accurate computational models of blood flow in microvascular networks. The experimental approaches developed in this work provide a foundation for further examining the characteristics of microhaemodynamics. PMID:24950214

  2. Cryopreserved red blood cells are superior to standard liquid red blood cells.

    PubMed

    Hampton, David A; Wiles, Connor; Fabricant, Loïc J; Kiraly, Laszlo; Differding, Jerome; Underwood, Samantha; Le, Dinh; Watters, Jennifer; Schreiber, Martin A

    2014-07-01

    Liquid preserved packed red blood cell (LPRBC) transfusions are used to treat anemia and increase end-organ perfusion. Throughout their storage duration, LPRBCs undergo biochemical and structural changes collectively known as the storage lesion. These changes adversely affect perfusion and oxygen off-loading. Cryopreserved RBCs (CPRBC) can be stored for up to 10 years and potentially minimize the associated storage lesion. We hypothesized that CPRBCs maintain a superior biochemical profile compared with LPRBCs. This was a prospective, randomized, double-blinded study. Adult trauma patients with an Injury Severity Score (ISS) greater than 4 and an anticipated 1-U to 2-U transfusion of PRBCs were eligible. Enrolled patients were randomized to receive either CPRBCs or LPRBCs. Serum proteins (haptoglobin, serum amyloid P, and C-reactive protein), proinflammatory and anti-inflammatory cytokines, d-dimer, nitric oxide, and 2,3-DPG concentrations were analyzed. Mann-Whitney U-test and Wilcoxon rank sum test were used to assess significance (p < 0.05). Fifty-seven patients were enrolled (CPRBC, n = 22; LPRBC, n = 35). The LPRBC group's final interleukin 8, tumor necrosis factor α, and d-dimer concentrations were elevated compared with their pretransfusion values (p < 0.05). After the second transfused units, 2,3-DPG was higher in the patients receiving CPRBCs (p < 0.05); this difference persisted throughout the study. Finally, serum protein concentrations were decreased in the transfused CPRBC units compared with LPRBC (p < 0.01). CPRBC transfusions have a superior biochemical profile: an absent inflammatory response, attenuated fibrinolytic state, and increased 2,3-DPG. A blood banking system using both storage techniques will offer the highest-quality products to critically injured patients virtually independent of periodic changes in donor availability and transfusion needs. Therapeutic study, level II.

  3. Red blood cells transfusion in intensive care unit.

    PubMed

    Volpato, Solange Emanuelle; Ferreira, Jovino Dos Santos; Ferreira, Vera Lúcia Paes Cavalcanti; Ferreira, David Cavalcanti

    2009-12-01

    The anemia is a common problem upon admission of the patients in the intensive care unit being the red blood cell transfusion a frequent therapeutic. The causes of anemia in critical patients who under go red blood cell transfusion are several: acute loss of blood after trauma, gastrointestinal hemorrhage, surgery amongst others. Currently, few studies are available regarding the use of blood components in patients at intensive care unit. Although blood transfusions are frequent in intensive care unit, the optimized criteria for handling are not clearly defined, with no available guidelines. To analyze the clinical indications of the use of the red blood cell in the intensive care unit. The clinical history of the patients admitted in the intensive care unit were analyzed, revisiting which had have red blood cell transfusion in the period between January 1st 2005 and December 31 2005. The study was accepted by the Research Ethics Committee - Comitê de Ética em Pesquisa (CEP) - of the University of South of Santa Catarina (UNISUL). The transfusion rate was 19,33, and the majority of the patients were of the male gender. Their age prevalence was of 60 years old or older. The mortality rate among patients who under went red blood cell transfusion died was of 38,22%. The transfusions criterias were low serum hemoglobin (78%) and the hemoglobin pre - transfusion was 8,11 g/dL. Politrauma and sepsis/sepsis chock were the pre diagnosis criteria. A low hemoglobin level is the main clinical criteria with average hemoglobin pre - transfusion was 8,11 g/dL.

  4. Reflectance confocal microscopy of red blood cells: simulation and experiment.

    PubMed

    Zeidan, Adel; Yelin, Dvir

    2015-11-01

    Measuring the morphology of red blood cells is important for clinical diagnosis, providing valuable indications on a patient's health. In this work, we have simulated the appearance of normal red blood cells under a reflectance confocal microscope and discovered unique relations between the morphological parameters and the resulting characteristic interference patterns of the cell. The simulation results showed good agreement with in vitro reflectance confocal images of red blood cells, acquired using spectrally encoded flow cytometry that imaged the cells in a linear flow without artificial staining. By matching the simulated patterns to confocal images of the cells, this method could be used for measuring cell morphology in three dimensions and for studying their physiology.

  5. Method for determining properties of red blood cells

    SciTech Connect

    Gourley, Paul L.

    2001-01-01

    A method for quantifying the concentration of hemoglobin in a cell, and indicia of anemia, comprises determining the wavelength of the longitudinal mode of a liquid in a laser microcavity; determining the wavelength of the fundamental transverse mode of a red blood cell in the liquid in the laser microcavity; and determining if the cell is anemic from the difference between the wavelength of the longitudinal mode and the fundamental transverse mode. In addition to measuring hemoglobin, the invention includes a method using intracavity laser spectroscopy to measure the change in spectra as a function of time for measuring the influx of water into a red blood cell and the cell's subsequent rupture.

  6. Photoacoustic response of suspended and hemolyzed red blood cells

    NASA Astrophysics Data System (ADS)

    Saha, Ratan K.; Karmakar, Subhajit; Roy, Madhusudan

    2013-07-01

    The effect of confinement of hemoglobin molecules on photoacoustic (PA) signal is studied experimentally. The PA amplitudes for samples with suspended red blood cells (SRBCs) and hemolyzed red blood cells (HRBCs) were found to be comparable at each hematocrit for 532 nm illumination. The difference between the corresponding amplitudes increased with increasing hematocrit for 1064 nm irradiation. For example, the PA amplitude for the SRBCs was about 260% higher than that of the HRBCs at 40% hematocrit. This observation may help to develop a PA method detecting hemolysis noninvasively.

  7. Fibrinogen, red blood cells, and factor XIII in venous thrombosis.

    PubMed

    Walton, B L; Byrnes, J R; Wolberg, A S

    2015-06-01

    Cardiovascular disease is the leading cause of death and disability worldwide. Among cardiovascular causes of death, venous thrombosis (VT) is ranked third most common in the world. Venous thrombi have high red blood cell and fibrin content; however, the pathophysiologic mechanisms that contribute to venous thrombus composition and stability are still poorly understood. This article reviews biological, biochemical, and biophysical contributions of fibrinogen, factor XIII, and red blood cells to VT, and new evidence suggesting interactions between these components mediate venous thrombus composition and size.

  8. Backward elastic light scattering of malaria infected red blood cells

    NASA Astrophysics Data System (ADS)

    Lee, Seungjun; Lu, Wei

    2011-08-01

    We investigated the backward light scattering pattern of healthy and malaria (Plasmodium falciparum) parasitized red blood cells. The spectrum could clearly distinguish between predominant ring stage infected blood cells and healthy blood cells. Further, we found that infected samples mixed with different stages of P. falciparum showed different signals, suggesting that even variance in parasite stages could also be detected by the spectrum. These results together with the backward scattering technique suggest the potential of non-invasive diagnosis of malaria through light scattering of blood cells near the surface of human body, such as using eyes or skin surface.

  9. Freeze-Dried Human Red Blood Cells

    DTIC Science & Technology

    1991-07-12

    cells with 5 1Cr sodium chromate, collection of urine and peripheral blood samples, 5 1Cr organ uptake, whole body gamma imaging, and calculation of whole...7. Subject does not have a history of: - Renal disorders or BUN, creatinine, uric acid, sodium , potassium or chloride values outside the...uric acid, calcium, inorganic phosphorus, glucose, sodium , potassium, chloride, bicarbonate. Coagulation: prothrombin time (subject and control) and

  10. Image classification of unlabeled malaria parasites in red blood cells.

    PubMed

    Zheng Zhang; Ong, L L Sharon; Kong Fang; Matthew, Athul; Dauwels, Justin; Ming Dao; Asada, Harry

    2016-08-01

    This paper presents a method to detect unlabeled malaria parasites in red blood cells. The current "gold standard" for malaria diagnosis is microscopic examination of thick blood smear, a time consuming process requiring extensive training. Our goal is to develop an automate process to identify malaria infected red blood cells. Major issues in automated analysis of microscopy images of unstained blood smears include overlapping cells and oddly shaped cells. Our approach creates robust templates to detect infected and uninfected red cells. Histogram of Oriented Gradients (HOGs) features are extracted from templates and used to train a classifier offline. Next, the ViolaJones object detection framework is applied to detect infected and uninfected red cells and the image background. Results show our approach out-performs classification approaches with PCA features by 50% and cell detection algorithms applying Hough transforms by 24%. Majority of related work are designed to automatically detect stained parasites in blood smears where the cells are fixed. Although it is more challenging to design algorithms for unstained parasites, our methods will allow analysis of parasite progression in live cells under different drug treatments.

  11. Image analysis of nucleated red blood cells.

    PubMed

    Zajicek, G; Shohat, M; Melnik, Y; Yeger, A

    1983-08-01

    Bone marrow smears stained with Giemsa were scanned with a video camera under computer control. Forty-two cells representing the six differentiation classes of the red bone marrow were sampled. Each cell was digitized into 70 X 70 pixels, each pixel representing a square area of 0.4 micron2 in the original image. The pixel gray values ranged between 0 and 255. Zero stood for white, 255 represented black, while the numbers in between stood for the various shades of gray. After separation and smoothing the images were processed with a Sobel operator outlining the points of steepest gray level change in the cell. These points constitute a closed curve denominated as inner cell boundary, separating the cell into an inner and an outer region. Two types of features were extracted from each cell: form features, e.g., area and length, and gray level features. Twenty-two features were tested for their discriminative merit. After selecting 16, the discriminant analysis program classified correctly all 42 cells into the 6 classes.

  12. Red blood cell and iron metabolism during space flight

    NASA Technical Reports Server (NTRS)

    Smith, Scott M.

    2002-01-01

    Space flight anemia is a widely recognized phenomenon in astronauts. Reduction in circulating red blood cells and plasma volume results in a 10% to 15% decrement in circulatory volume. This effect appears to be a normal physiologic adaptation to weightlessness and results from the removal of newly released blood cells from the circulation. Iron availability increases, and (in the few subjects studied) iron stores increase during long-duration space flight. The consequences of these changes are not fully understood.

  13. Red blood cell and iron metabolism during space flight

    NASA Technical Reports Server (NTRS)

    Smith, Scott M.

    2002-01-01

    Space flight anemia is a widely recognized phenomenon in astronauts. Reduction in circulating red blood cells and plasma volume results in a 10% to 15% decrement in circulatory volume. This effect appears to be a normal physiologic adaptation to weightlessness and results from the removal of newly released blood cells from the circulation. Iron availability increases, and (in the few subjects studied) iron stores increase during long-duration space flight. The consequences of these changes are not fully understood.

  14. Theory of non-Newtonian viscosity of red blood cell suspension: effect of red cell deformation.

    PubMed

    Murata, T

    1983-01-01

    The effects of the deformation of red blood cells on non-Newtonian viscosity of a concentrated red cell suspension are investigated theoretically. To simplify the problem an elastic spherical shell filled with an incompressible Newtonian fluid is considered as a model of a normal red cell. The equation of the surface of the shell suspended in a steady simple shear flow is calculated on the assumption that the deformation from a spherical shape is very small. The relative viscosity of a concentrated suspension of such particles is obtained based on the "free surface cell" method proposed by Happel. It is shown that the relative viscosity decreases as the shear rate increases.

  15. Observation of dynamic subdomains in red blood cells.

    PubMed

    Popescu, Gabriel; Badizadegan, Kamran; Dasari, Ramachandra R; Feld, Michael S

    2006-01-01

    We quantify the nanoscale structure and low-frequency dynamics associated with live red blood cells. The membrane displacements are measured using quantitative phase images provided by Fourier phase microscopy, with an average path-length stability of 0.75 nm over 45 min. The results reveal the existence of dynamic, independent subdomains across the cells that fluctuate at various dominant frequencies.

  16. Shape of red blood cells in contact with artificial surfaces.

    PubMed

    Grzhibovskis, Richards; Krämer, Elisabeth; Bernhardt, Ingolf; Kemper, Björn; Zanden, Carl; Repin, Nikolay V; Tkachuk, Bogdan V; Voinova, Marina V

    2017-03-01

    The phenomenon of physical contact between red blood cells and artificial surfaces is considered. A fully three-dimensional mathematical model of a bilayer membrane in contact with an artificial surface is presented. Numerical results for the different geometries and adhesion intensities are found to be in agreement with experimentally observed geometries obtained by means of digital holographic microscopy.

  17. Surface Enhanced Raman Scattering of Whole Human Blood, Blood Plasma and Red Blood Cells: Cellular Processes and Bioanalytical Sensing

    PubMed Central

    Premasiri, W. R.; Lee, J. C.; Ziegler, L. D.

    2013-01-01

    SERS spectra of whole human blood, blood plasma and red blood cells on Au nanoparticle SiO2 substrates excited at 785 nm have been observed. For the sample preparation procedure employed here, the SERS spectrum of whole blood arises from the blood plasma component only. This is in contrast to the normal Raman spectrum of whole blood excited at 785 nm and open to ambient air, which is exclusively due to the scattering of oxyhemoglobin. The SERS spectrum of whole blood shows a storage time dependence that is not evident in the non-SERS Raman spectrum of whole blood. Hypoxanthine, a product of purine degradation, dominates the SERS spectrum of blood after ~10 – 20 hours of storage at 8 °C. The corresponding SERS spectrum of plasma isolated from the stored blood shows the same temporal release of hypoxanthine. Thus, blood cellular components (red blood cells, white blood cells and/or platelets) are releasing hypoxanthine into the plasma over this time interval. The SERS spectrum of red blood cells (RBCs) excited at 785 nm is reported for the first time and exhibits well known heme group marker bands, as well as other bands that may be attributed to cell membrane components or protein denaturation contributions. SERS, as well as normal Raman spectra, of oxy- and met-RBCs are reported and compared. These SERS results can have significant impact in the area of clinical diagnostics, blood supply management and forensics. PMID:22780445

  18. Deformability of red blood cells and its relation to blood trauma in rotary blood pumps.

    PubMed

    Watanabe, Nobuo; Sakota, Daisuke; Ohuchi, Katsuhiro; Takatani, Setsuo

    2007-05-01

    In this study, mechanical trauma to red blood cells was evaluated by conventional hemolysis test and a newly developed cyclically reversing shear flow generator. The fresh porcine blood obtained from a local slaughterhouse was subjected to the conventional hemolysis test using a commercial centrifugal blood pump for the duration of 8 h. The measurements consisted of (i) plasma-free hemoglobin based on the standard optical measurement and (ii) the deformability of red blood cells (RBCs) using a cyclically reversing shear flow generator and microscope image acquisition system. The deformability of RBCs was expressed by the L/W value where L and W were the longer and shorter axes of the elongated RBCs' images. Although the plasma-free hemoglobin level increased with the pumping duration, the L/W remained unchanged for the duration of 8 h of pumping to indicate no alteration in the deformability. It was speculated that (i) although RBCs might have been circulated for so many times through the test pump, after each exposure to mechanical stress, RBCs might have recovered, and net effect due to shear stress-exposure time might have been small; and (ii) RBCs' deformability might be maintained near normal until sudden burst or membrane rupture, or the hemoglobin might have continuously leaked through the pores of the thinned membrane created by the mechanical stress. The deformability testing under a fluctuating shear flow could be a new method to quantify subhemolytic mechanical damage that has been accumulated in the RBCs' membrane and that may not be assessed by the conventional hemolysis test.

  19. Antigen negative red blood cell inventory of Indian blood donors.

    PubMed

    Kulkarni, Swati; Vasantha, K; Ghosh, Kanjaksha

    2016-08-01

    Screening the donor population for clinically important antigens and creating a database of phenotyped donors will eliminate the tedious task of large scale screening for antigen negative units. The aim of the present study is to identify donors lacking common antigens and a combination of common antigens to establish an antigen negative inventory. Blood samples of 1221 regular blood donors were phenotyped for the clinically important common antigens of the Rh, Duffy, Kell, Kidd and MNS blood group systems using standard tube technique. Out of 1221 total donors tested, we observed that 261 donors lacked a combination of clinically important common antigens (C, D, e, Fya, Jka, s). After excluding the RhD negative donors in this study 15.56% lacked a combination of two or three common antigens. Of all donors, 3.2% lacked Fya and Jka antigens, 1.96% Fya and s, 1.88% Jka and s antigens and 0.57% lacked three common antigens. An antigen negative inventory of donors who lack a single common antigen or a combination of common antigens was prepared from regular donors which will prove useful for efficient management of transfusion therapy in patients with multiple antibodies against common antigens. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Full dynamics of a red blood cell in shear flow.

    PubMed

    Dupire, Jules; Socol, Marius; Viallat, Annie

    2012-12-18

    At the cellular scale, blood fluidity and mass transport depend on the dynamics of red blood cells in blood flow, specifically on their deformation and orientation. These dynamics are governed by cellular rheological properties, such as internal viscosity and cytoskeleton elasticity. In diseases in which cell rheology is altered genetically or by parasitic invasion or by changes in the microenvironment, blood flow may be severely impaired. The nonlinear interplay between cell rheology and flow may generate complex dynamics, which remain largely unexplored experimentally. Under simple shear flow, only two motions, "tumbling" and "tank-treading," have been described experimentally and relate to cell mechanics. Here, we elucidate the full dynamics of red blood cells in shear flow by coupling two videomicroscopy approaches providing multidirectional pictures of cells, and we analyze the mechanical origin of the observed dynamics. We show that contrary to common belief, when red blood cells flip into the flow, their orientation is determined by the shear rate. We discuss the "rolling" motion, similar to a rolling wheel. This motion, which permits the cells to avoid energetically costly deformations, is a true signature of the cytoskeleton elasticity. We highlight a hysteresis cycle and two transient dynamics driven by the shear rate: an intermittent regime during the "tank-treading-to-flipping" transition and a Frisbee-like "spinning" regime during the "rolling-to-tank-treading" transition. Finally, we reveal that the biconcave red cell shape is highly stable under moderate shear stresses, and we interpret this result in terms of stress-free shape and elastic buckling.

  1. Red Blood Cell Polymorphism and Susceptibility to Plasmodium vivax

    PubMed Central

    Zimmerman, Peter A.; Ferreira, Marcelo U.; Howes, Rosalind E.; Mercereau-Puijalon, Odile

    2013-01-01

    Resistance to Plasmodium vivax blood-stage infection has been widely recognised to result from absence of the Duffy (Fy) blood group from the surface of red blood cells (RBCs) in individuals of African descent. Interestingly, recent studies from different malaria-endemic regions have begun to reveal new perspectives on the association between Duffy gene polymorphism and P. vivax malaria. In Papua New Guinea and the Americas, heterozygous carriers of a Duffy-negative allele are less susceptible to P. vivax infection than Duffy-positive homozygotes. In Brazil, studies show that the Fya antigen, compared to Fyb, is associated with lower binding to the P. vivax Duffy-binding protein and reduced susceptibility to vivax malaria. Additionally, it is interesting that numerous studies have now shown that P. vivax can infect RBCs and cause clinical disease in Duffy-negative people. This suggests that the relationship between P. vivax and the Duffy antigen is more complex than customarily described. Evidence of P. vivax Duffy-independent red cell invasion indicates that the parasite must be evolving alternative red cell invasion pathways. In this chapter, we review the evidence for P. vivax Duffy-dependent and Duffy-independent red cell invasion. We also consider the influence of further host gene polymorphism associated with malaria endemicity on susceptibility to vivax malaria. The interaction between the parasite and the RBC has significant potential to influence the effectiveness of P. vivax-specific vaccines and drug treatments. Ultimately, the relationships between red cell polymorphisms and P. vivax blood-stage infection will influence our estimates on the population at risk and efforts to eliminate vivax malaria. PMID:23384621

  2. Red blood cell-derived microparticles: An overview.

    PubMed

    Westerman, Maxwell; Porter, John B

    2016-07-01

    The red blood cell (RBC) is historically the original parent cell of microparticles (MPs). In this overview, we describe the discovery and the early history of red cell-derived microparticles (RMPs) and present an overview of the evolution of RMP. We report the formation, characteristics, effects of RMP and factors which may affect RMP evaluation. The review examines RMP derived from both normal and pathologic RBC. The pathologic RBC studies include sickle cell anemia (SCA), sickle cell trait (STr), thalassemia intermedia (TI), hereditary spherocytosis (HS), hereditary elliptocytosis (HE), hereditary stomatocytosis (HSt) and glucose-6-phosphate dehydrogenase deficiency (G6PD). Copyright © 2016 Elsevier Inc. All rights reserved.

  3. Identification and red blood cell automated counting from blood smear images using computer-aided system.

    PubMed

    Acharya, Vasundhara; Kumar, Preetham

    2017-08-17

    Red blood cell count plays a vital role in identifying the overall health of the patient. Hospitals use the hemocytometer to count the blood cells. Conventional method of placing the smear under microscope and counting the cells manually lead to erroneous results, and medical laboratory technicians are put under stress. A computer-aided system will help to attain precise results in less amount of time. This research work proposes an image-processing technique for counting the number of red blood cells. It aims to examine and process the blood smear image, in order to support the counting of red blood cells and identify the number of normal and abnormal cells in the image automatically. K-medoids algorithm which is robust to external noise is used to extract the WBCs from the image. Granulometric analysis is used to separate the red blood cells from the white blood cells. The red blood cells obtained are counted using the labeling algorithm and circular Hough transform. The radius range for the circle-drawing algorithm is estimated by computing the distance of the pixels from the boundary which automates the entire algorithm. A comparison is done between the counts obtained using the labeling algorithm and circular Hough transform. Results of the work showed that circular Hough transform was more accurate in counting the red blood cells than the labeling algorithm as it was successful in identifying even the overlapping cells. The work also intends to compare the results of cell count done using the proposed methodology and manual approach. The work is designed to address all the drawbacks of the previous research work. The research work can be extended to extract various texture and shape features of abnormal cells identified so that diseases like anemia of inflammation and chronic disease can be detected at the earliest.

  4. Partitioning of red blood cell aggregates in bifurcating microscale flows

    NASA Astrophysics Data System (ADS)

    Kaliviotis, E.; Sherwood, J. M.; Balabani, S.

    2017-03-01

    Microvascular flows are often considered to be free of red blood cell aggregates, however, recent studies have demonstrated that aggregates are present throughout the microvasculature, affecting cell distribution and blood perfusion. This work reports on the spatial distribution of red blood cell aggregates in a T-shaped bifurcation on the scale of a large microvessel. Non-aggregating and aggregating human red blood cell suspensions were studied for a range of flow splits in the daughter branches of the bifurcation. Aggregate sizes were determined using image processing. The mean aggregate size was marginally increased in the daughter branches for a range of flow rates, mainly due to the lower shear conditions and the close cell and aggregate proximity therein. A counterintuitive decrease in the mean aggregate size was apparent in the lower flow rate branches. This was attributed to the existence of regions depleted by aggregates of certain sizes in the parent branch, and to the change in the exact flow split location in the T-junction with flow ratio. The findings of the present investigation may have significant implications for microvascular flows and may help explain why the effects of physiological RBC aggregation are not deleterious in terms of in vivo vascular resistance.

  5. Partitioning of red blood cell aggregates in bifurcating microscale flows

    PubMed Central

    Kaliviotis, E.; Sherwood, J. M.; Balabani, S.

    2017-01-01

    Microvascular flows are often considered to be free of red blood cell aggregates, however, recent studies have demonstrated that aggregates are present throughout the microvasculature, affecting cell distribution and blood perfusion. This work reports on the spatial distribution of red blood cell aggregates in a T-shaped bifurcation on the scale of a large microvessel. Non-aggregating and aggregating human red blood cell suspensions were studied for a range of flow splits in the daughter branches of the bifurcation. Aggregate sizes were determined using image processing. The mean aggregate size was marginally increased in the daughter branches for a range of flow rates, mainly due to the lower shear conditions and the close cell and aggregate proximity therein. A counterintuitive decrease in the mean aggregate size was apparent in the lower flow rate branches. This was attributed to the existence of regions depleted by aggregates of certain sizes in the parent branch, and to the change in the exact flow split location in the T-junction with flow ratio. The findings of the present investigation may have significant implications for microvascular flows and may help explain why the effects of physiological RBC aggregation are not deleterious in terms of in vivo vascular resistance. PMID:28303921

  6. Color contrast of red blood cells on solid substrate

    NASA Astrophysics Data System (ADS)

    Paiziev, Adkham A.

    2013-02-01

    In present study we developed the new method of colour visualization of red blood cells without using any chemical staining. The method based on physical phenomena a white light interference on thin transparent films. It is shown that in the case of thin human blood smears colour interference contrast occurs on solid polished substrates. The best contrast shows substrates with maximal refractive index (Mo, W, Si). These materials have been selected as substrate instead of ordinary microscopic slide in reflected light microscopy. It is shown that reflection of incident white light from blood cell surface and boundary cell-substrate generate two coherent lights. The second one (object signal) after passing through red blood cell gathers additional phase and after interference interaction with reference signal (light reflected from outer cell surface) enables cell image in colour. Number of blood smears of healthy persons (control) and patients who were diagnosed with cancer are presented. It is concluded that the offered method may be used as an effective diagnostic tool to detect early stage blood cells lesion by its interference painting in white light. Offered method may be used in research laboratories, hospitals, diagnostic centres, emergency medicine and other as complementary diagnostic tool to present convenient optical and electron microscopy technique.

  7. Quantification of red blood cell deformation at high-hematocrit blood flow in microvessels.

    PubMed

    Alizadehrad, Davod; Imai, Yohsuke; Nakaaki, Keita; Ishikawa, Takuji; Yamaguchi, Takami

    2012-10-11

    The deformation of red blood cells in microvessels was investigated numerically for various vessel diameters, hematocrits, and shear rates. We simulated blood flow in circular channels with diameters ranging from 9 to 50 μm, hematocrits from 20% to 45%, and shear rates from 20 to 150 s(-1) using a particle-based model with parallel computing. The apparent viscosity predicted by the simulation was in good agreement with previous experimental results. We quantified the deformation of red blood cells as a function of radial position. The numerical results demonstrated that because of the shape transition in response to local shear stress and the wall effect, the radial variation of red blood cell deformation in relatively large microvessels could be classified into three different regions: near-center, middle, and near-wall regions. Effects of the local shear stress and wall varied with vessel diameter, hematocrit, and shear rate. Copyright © 2012 Elsevier Ltd. All rights reserved.

  8. Platelet and red blood cell indices in Harris platelet syndrome.

    PubMed

    Naina, Harris V K; Harris, Samar

    2010-01-01

    Inherited thrombocytopenias, including inherited giant platelet disorders (IGPD) or macro thrombocytopenias are relatively rare, but their prevalence is likely underestimated from complexities of diagnosis and a spectrum of subclinical phenotypes. Harris platelet syndrome (HPS) is the most common IGPD reported from the Indian subcontinent. Of note there are an increased number of hemoglobinopathies reported from the geographic location. We analysed red blood cell and platelet indices of blood donors with HPS from the north eastern part of India and compared them with blood indices of blood donors of south India. We found a statistically significant lower platelet count in blood donors with HPS (median, range) 132 (71-267) vs. 252 (160-478) as compared to donors from south India (P < 0.001). Mean platelet volume (MPV) was higher in donors with HPS 13.1, (range 12-21.9 fl) as compared to donors from south India 7.35 (range 6-9.2 fl) (P < 0.001). This study showed that blood donors with HPS had a low median platelet bio-mass 0.17 (0.10-0.38%) vs. 0.19 (0.13-0.28%) in donors from south India. The platelet distribution width (PDW) was 17.4 (14.9-19.6) in donors with HPS vs. 16.38 (15.2-18.5) in south Indian blood donors (P < 0.001). Thirty-three donors with HPS had a normal platelet count with MPV more than 12 fL. Only donors with HPS had giant platelets and thrombocytopenia on peripheral blood smear examination. None of these donors had Dohle body inclusion in their leukocytes. Compared to donors from south India, donors with HPS had a significantly lower hemoglobin 13.8 (12-16.3 gm/dL) vs. 14.8 (12-18) respectively (P < 0.001) while red distribution width (RDW) was higher in HPS 13.6 (11.5-16.7) vs. 12.8 (11.4-15.1). However we did not find any statistically significant difference in MCV, MCH, MCHC between the two groups. Peripheral blood smear did not show any obvious abnormal red blood cell morphology. In the blood donors with HPS we found a statistically higher MPV

  9. Low frequency electrorotation of fixed red blood cells.

    PubMed Central

    Georgieva, R; Neu, B; Shilov, V M; Knippel, E; Budde, A; Latza, R; Donath, E; Kiesewetter, H; Bäumler, H

    1998-01-01

    Electrorotation of fixed red blood cells has been investigated in the frequency range between 16 Hz and 30 MHz. The rotation was studied as a function of electrolyte conductivity and surface charge density. Between 16 Hz and 1 kHz, fixed red blood cells undergo cofield rotation. The maximum of cofield rotation occurs between 30 and 70 Hz. The position of the maximum depends weakly on the bulk electrolyte conductivity and surface charge density. Below 3.5 mS/m, the cofield rotation peak is broadened and shifted to higher frequencies accompanied by a decrease of the rotation speed. Surface charge reduction leads to a decrease of the rotation speed in the low frequency range. These observations are consistent with the recently developed electroosmotic theory of low frequency electrorotation. PMID:9545070

  10. Aggregation of red blood cells: From rouleaux to clot formation

    NASA Astrophysics Data System (ADS)

    Wagner, Christian; Steffen, Patrick; Svetina, Saša

    2013-06-01

    Red blood cells are known to form aggregates in the form of rouleaux. This aggregation process is believed to be reversible, but there is still no full understanding on the adhesion mechanism. There are at least two competing models, based either on bridging or on depletion. We review recent experimental results on the single cell level and theoretical analyses of the depletion model and of the influence of the cell shape on the adhesion strength. Another important aggregation mechanism is caused by activation of platelets. This leads to clot formation which is life-saving in the case of wound healing, but also a major cause of death in the case of a thrombus induced stroke. We review historical and recent results on the participation of red blood cells in clot formation.

  11. Magnetic nanoparticle effects on the red blood cells

    NASA Astrophysics Data System (ADS)

    Creangă, D. E.; Culea, M.; Nădejde, C.; Oancea, S.; Curecheriu, L.; Racuciu, M.

    2009-05-01

    In vitro tests on magnetite colloidal nanoparticles effects upon animal red blood cells were carried out. Magnetite cores were stabilized with citric acid in the form of biocompatible magnetic fluid administrated in different dilutions in the whole blood samples. The hemolysis extent was found increased up to 2.75 in horse blood and respectively up to 2.81 in the dog blood. The electronic transitions assigned to the heme group were found shifted with about 500 cm-1 or, respectively, affected by supplementary vibronic structures. The Raman vibrations assigned to oxyhemoglobin were much diminished in intensity probably due to the bonding of OH group from citrate shell to the heme iron ion.

  12. Red blood cells flows in rectilinear microfluidic chip.

    PubMed

    Anandan, P; Ortiz, D; Intaglietta, M; Cabrales, P J; Bucolo, M

    2015-01-01

    The red blood cells flow in a controlled environment as a microfluidic chip with a rectilinear geometry was investigated. The optical monitoring performed by an automatic Particle Image Velocimetry procedure has allowed a quantitative analysis on flow features. Various parameters such as velocity, shear rate, strain rate, vorticity, divergence were extracted. The comparisons of the results obtained from the different experiments was used for the overall understanding of the RBC movements in different conditions and the establishment of the analysis procedure.

  13. My passion and passages with red blood cells.

    PubMed

    Hoffman, Joseph F

    2008-01-01

    This article mainly presents, in sequential panels of time, an overview of my professional involvements and laboratory experiences. I became smitten with red blood cells early on, and this passion remains with me to this day. I highlight certain studies, together with those who performed the work, recognizing that it was necessary to limit the details and the topics chosen for discussion. I am uncertain of the interest a personal account has for others, but at least it's here for the record.

  14. Characterization of red blood cells (RBCs) using dual Brillouin/Raman micro-spectroscopy

    NASA Astrophysics Data System (ADS)

    Meng, Zhaokai; Bustamante-Lopez, Sandra C.; Yakovlev, Vladislav V.; Meissner, Kenith E.

    2016-04-01

    Erythrocytes, or red blood cells, transport oxygen to and carbon dioxide from the body's tissues and organs. Red blood cell mechanical properties are altered in a number of diseases such as sickle cell anaemia and malaria. Additionally, mechanically modified red blood cell ghosts are being considered as a long-term, biocompatible carrier for drug delivery and for blood analyte sensing. Brillouin spectroscopy enables viscoelastic characterization of samples at the microscale. In this report, Brillouin spectroscopy is applied to characterize the mechanical properties of red blood cells and red blood cell ghosts.

  15. Microvascular blood flow resistance: Role of red blood cell migration and dispersion.

    PubMed

    Katanov, Dinar; Gompper, Gerhard; Fedosov, Dmitry A

    2015-05-01

    Microvascular blood flow resistance has a strong impact on cardiovascular function and tissue perfusion. The flow resistance in microcirculation is governed by flow behavior of blood through a complex network of vessels, where the distribution of red blood cells across vessel cross-sections may be significantly distorted at vessel bifurcations and junctions. In this paper, the development of blood flow and its resistance starting from a dispersed configuration of red blood cells is investigated in simulations for different hematocrit levels, flow rates, vessel diameters, and aggregation interactions between red blood cells. Initially dispersed red blood cells migrate toward the vessel center leading to the formation of a cell-free layer near the wall and to a decrease of the flow resistance. The development of cell-free layer appears to be nearly universal when scaled with a characteristic shear rate of the flow. The universality allows an estimation of the length of a vessel required for full flow development, lc ≲ 25D, for vessel diameters in the range 10 μm < D < 100 μm. Thus, the potential effect of red blood cell dispersion at vessel bifurcations and junctions on the flow resistance may be significant in vessels which are shorter or comparable to the length lc. Aggregation interactions between red blood cells generally lead to a reduction of blood flow resistance. The simulations are performed using the same viscosity for both external and internal fluids and the RBC membrane viscosity is not considered; however, we discuss how the viscosity contrast may affect the results. Finally, we develop a simple theoretical model which is able to describe the converged cell-free-layer thickness at steady-state flow with respect to flow rate. The model is based on the balance between a lift force on red blood cells due to cell-wall hydrodynamic interactions and shear-induced effective pressure due to cell-cell interactions in flow. We expect that these results can

  16. Photosensitized inactivation of infectious agents for sterilization of red blood cell concentrates and whole blood

    NASA Astrophysics Data System (ADS)

    Judy, Millard M.; Matthews, James Lester; Sogandares-Bernal, Franklin M.; Newman, Joseph T.; Chanh, Tran C.; Marengo-Rowe, Alain J.

    1992-06-01

    More than 10 million units of human blood components are transfused annually in the United States. Although donor screening and testing have greatly lowered the risk of transmission of viral and protozoan infectious agents, additional sterilization procedures which also preserve blood component function would be of significant value. Use of visible-light-range photosensitizers for sterilization of red blood cells is currently being aggressively investigated in laboratory-scale optical-mechanical systems. Both the photochemical sterilization process and the optical-mechanical system must operate without introducing significant alteration in the properties of the red cells. With successful demonstration of the efficacy and safety of these sterilization techniques, implementation in the blood bank setting will require scale-up to optical-mechanical systems capable of handling approximately 50,000 units daily in 500 - 1,000 blood banks in the United States.

  17. Blood flow simulation on a role for red blood cells in platelet adhesion

    NASA Astrophysics Data System (ADS)

    Shimizu, Kazuya; Sugiyama, Kazuyasu; Takagi, Shu

    2016-11-01

    Large-scale blood flow simulations were conducted and a role for red blood cells in platelet adhesion was discussed. The flow conditions and hematocrit values were set to the same as corresponding experiments, and the numerical results were compared with the measurements. Numerical results show the number of platelets adhered on the wall is increased with the increase in hematocrit values. The number of adhered platelets estimated from the simulation was approximately 28 (per 0.01 square millimeter per minute) for the hematocrit value of 20%. These results agree well with the experimental results qualitatively and quantitatively, which proves the validity of the present numerical model including the interaction between fluid and many elastic bodies and the modeling of platelet adhesion. Numerical simulation also reproduces the behavior of red blood cells in the blood flow and their role in platelet adhesion. Red blood cells deform to a flat shape and move towards channel center region. In contrast, platelets are pushed out and have many chances to contact with the wall. As a result, the large number of adhered platelets is observed as hematocrit values becomes high. This result indicates the presence of red blood cells plays a crucial role in platelet adhesion.

  18. Rheology of red blood cell aggregation by computer simulation

    NASA Astrophysics Data System (ADS)

    Liu, Yaling; Liu, Wing Kam

    2006-12-01

    The aggregation of red blood cells (RBC) induced by the interactions between RBCs is a dominant factor of the in vitro rheological properties of blood, and existing models of blood do not contain full cellular information. In this work, we introduce a new three-dimensional model that couples Navier-Stokes equations with cell interactions to investigate RBC aggregation and its effect on blood rheology. It consists of a depletion mediated aggregation model to describe the interactions of RBCs and an immersed continuum model to track the deformation/motion of RBCs in blood plasma. To overcome the large deformation of RBCs, the meshfree method is used to model the RBCs. Three important phenomena in blood rheology are successfully captured and studied via this approach: the shear rate dependence of blood viscosity, the influence of cell rigidity on blood viscosity, and the Fahraeus-Lindqvist effect. As a microscopic illustration of the shear-rate dependence of the blood's viscoelasticity, the disaggregation of an RBC rouleau at shear rates varying between 0.125 and 24 s -1 is modeled. Lower RBC deformability and higher shear rates above 0.5 s -1 are found to facilitate disaggregation. The effective viscosities at different shear rates and for cells with different deformabilities are simulated. The numerical results are shown to agree with the reported experimental measurements. The Fahraeus-Lindqvist effect is, for the first time, studied through three-dimensional numerical simulations of blood flow through tubes with different diameters and is shown to be directly linked to axial-migration of deformable cells. This study shows that cell-cell interaction and cell deformability have significant effects on blood rheology in capillaries.

  19. Lysophosphatidylcholines: bioactive lipids generated during storage of blood components.

    PubMed

    Maślanka, Krystyna; Smoleńska-Sym, Gabriela; Michur, Halina; Wróbel, Agnieszka; Lachert, Elżbieta; Brojer, Ewa

    2012-02-01

    Transfusion-related acute lung injury (TRALI) is suggested to be a "two hit" event, resulting from priming and activation of pulmonary neutrophils. It is known that neutrophil activation may result from infusion of lysophosphatidylcholines (LysoPCs) accumulated during storage of blood components. The aim of our study was to verify whether the LysoPCs are released into the storage medium of blood components. We measured the LysoPCs concentration in the supernatants from stored apheresis platelet concentrates (PLTs), packed non-leukoreduced red blood cell concentrates (RBCs), leukoreduced red blood cell concentrates (L-RBCs), fresh frozen plasma (FFP) and donor plasma (control). Lipids were separated on high-performance thin-layer chromatography, detected by primulin spray and quantified by photodensitometric scanning. The LysoPCs concentration in donor plasma was similar to that in FFP. During storage the LysoPCs content in PLTs increased almost two-fold as compared to the fresh isolated platelets. In RBCs and L-RBCs the LysoPC level was very low or below detection limit and did not increase throughout the storage period. According to our observations bioactive LysoPCs may be considered a neutrophil-activating factor only following PLT transfusions but not RBCs transfusions.

  20. Structural analysis of red blood cell aggregates under shear flow.

    PubMed

    Chesnutt, J K W; Marshall, J S

    2010-03-01

    A set of measures of red blood cell (RBC) aggregates are developed and applied to examine the aggregate structure under plane shear and channel flows. Some of these measures are based on averages over the set of red blood cells which are in contact with each other at a given time. Other measures are developed by first fitting an ellipse to the planar projection of the aggregate, and then examining the area and aspect ratio of the fit ellipse as well as the orientations of constituent RBCs with respect to the fit ellipse axes. The aggregate structural measures are illustrated using a new mesoscale computational model for blood cell transport, collision and adhesion. The sensitivity of this model to change in adhesive surface energy density and shear rate on the aggregate structure is examined. It is found that the mesoscale model predictions exhibit reasonable agreement with experimental and theoretical data for blood flow in plane shear and channel flows. The new structural measures are used to examine the differences between predictions of two- and three-dimensional computations of the aggregate formation, showing that two-dimensional computations retain some of the important aspects of three-dimensional computations.

  1. Metabolic pathways that correlate with post-transfusion circulation of stored murine red blood cells

    PubMed Central

    de Wolski, Karen; Fu, Xiaoyoun; Dumont, Larry J.; Roback, John D.; Waterman, Hayley; Odem-Davis, Katherine; Howie, Heather L.; Zimring, James C.

    2016-01-01

    Transfusion of red blood cells is a very common inpatient procedure, with more than 1 in 70 people in the USA receiving a red blood cell transfusion annually. However, stored red blood cells are a non-uniform product, based upon donor-to-donor variation in red blood cell storage biology. While thousands of biological parameters change in red blood cells over storage, it has remained unclear which changes correlate with function of the red blood cells, as opposed to being co-incidental changes. In the current report, a murine model of red blood cell storage/transfusion is applied across 13 genetically distinct mouse strains and combined with high resolution metabolomics to identify metabolic changes that correlated with red blood cell circulation post storage. Oxidation in general, and peroxidation of lipids in particular, emerged as changes that correlated with extreme statistical significance, including generation of dicarboxylic acids and monohydroxy fatty acids. In addition, differences in anti-oxidant pathways known to regulate oxidative stress on lipid membranes were identified. Finally, metabolites were identified that differed at the time the blood was harvested, and predict how the red blood cells perform after storage, allowing the potential to screen donors at time of collection. Together, these findings map out a new landscape in understanding metabolic changes during red blood cell storage as they relate to red blood cell circulation. PMID:26921359

  2. Metabolic pathways that correlate with post-transfusion circulation of stored murine red blood cells.

    PubMed

    de Wolski, Karen; Fu, Xiaoyoun; Dumont, Larry J; Roback, John D; Waterman, Hayley; Odem-Davis, Katherine; Howie, Heather L; Zimring, James C

    2016-05-01

    Transfusion of red blood cells is a very common inpatient procedure, with more than 1 in 70 people in the USA receiving a red blood cell transfusion annually. However, stored red blood cells are a non-uniform product, based upon donor-to-donor variation in red blood cell storage biology. While thousands of biological parameters change in red blood cells over storage, it has remained unclear which changes correlate with function of the red blood cells, as opposed to being co-incidental changes. In the current report, a murine model of red blood cell storage/transfusion is applied across 13 genetically distinct mouse strains and combined with high resolution metabolomics to identify metabolic changes that correlated with red blood cell circulation post storage. Oxidation in general, and peroxidation of lipids in particular, emerged as changes that correlated with extreme statistical significance, including generation of dicarboxylic acids and monohydroxy fatty acids. In addition, differences in anti-oxidant pathways known to regulate oxidative stress on lipid membranes were identified. Finally, metabolites were identified that differed at the time the blood was harvested, and predict how the red blood cells perform after storage, allowing the potential to screen donors at time of collection. Together, these findings map out a new landscape in understanding metabolic changes during red blood cell storage as they relate to red blood cell circulation.

  3. Red blood cell damage by shear stress for different blood types

    NASA Astrophysics Data System (ADS)

    Arwatz, Gilad; Bedkowski, Katherine; Smits, Alexander

    2011-11-01

    In surgical practice, blood damage caused by medical devices is often a limiting factor in the duration of an acute procedure or in chronic exposures such as hemodialysis. In order to establish guidelines for designing medical devices, a study was conducted to determine the relationship between shear stress and damage to red blood cells using a concentric Couette device. By measuring the hemolysis level for various shear stresses and exposure times, a non-dimensional relationship between shear stress and blood damage for different blood types was established. Funding provided by Princeton University's Project X.

  4. Red blood cell transport mechanisms in polyester thread-based blood typing devices.

    PubMed

    Nilghaz, Azadeh; Ballerini, David R; Guan, Liyun; Li, Lizi; Shen, Wei

    2016-02-01

    A recently developed blood typing diagnostic based on a polyester thread substrate has shown great promise for use in medical emergencies and in impoverished regions. The device is easy to use and transport, while also being inexpensive, accurate, and rapid. This study used a fluorescent confocal microscope to delve deeper into how red blood cells were behaving within the polyester thread-based diagnostic at the cellular level, and how plasma separation could be made to visibly occur on the thread, making it possible to identify blood type in a single step. Red blood cells were stained and the plasma phase dyed with fluorescent compounds to enable them to be visualised under the confocal microscope at high magnification. The mechanisms uncovered were in surprising contrast with those found for a similar, paper-based method. Red blood cell aggregates did not flow over each other within the thread substrate as expected, but suffered from a restriction to their flow which resulted in the chromatographic separation of the RBCs from the liquid phase of the blood. It is hoped that these results will lead to the optimisation of the method to enable more accurate and sensitive detection, increasing the range of blood systems that can be detected.

  5. Depletion induced clustering of red blood cells in microchannels

    NASA Astrophysics Data System (ADS)

    Wagner, Christian; Brust, Mathias; Podgorski, Thomas; Coupier, Gwennou

    2012-11-01

    The flow properties of blood are determined by the physical properties of its main constituents, the red blood cells (RBC's). At low shear rates RBC's form aggregates, so called rouleaux. Higher shear rates can break them up and the viscosity of blood shows a shear thinning behavior. The physical origin of the rouleaux formation is not yet fully resolved and there are two competing models available. One predicts that the adhesion is induced by bridging of the plasma (macromolecular) proteins in-between two RBC's. The other is based on the depletion effect and thus predicts the absence of macromolecules in-between the cells of a rouleaux. Recent single cell force measurements by use of an AFM support strongly the depletion model. By varying the concentration of Dextran at different molecular weights we can control the adhesions strength. Measurements at low hematocrit in a microfluidic channel show that the number of size of clusters is determined by the depletion induced adhesion strength.

  6. Considerations of red blood cell molecular testing in transfusion medicine.

    PubMed

    Svensson, Annika M; Delaney, Meghan

    2015-01-01

    The field of transfusion medicine is on the threshold of a paradigm shift, as the technology for genotyping of red blood cell antigens, including US FDA-approved arrays, is now moving into standard practice. Access to cost-efficient, high-resolution genotyping has the potential to increase the quality of care by decreasing the risk for alloimmunization and incompatible transfusions in individuals on long-term blood transfusion protocols, including patient groups with hemoglobinopathies and other chronic diseases. Current and future applications of molecular methods in transfusion medicine and blood banking are discussed, with emphasis on indications for genotyping in various clinical scenarios. Furthermore, limitations of the current gold standard methodology and serology, as well as of contemporary molecular methodology, are examined.

  7. Image-based red cell counting for wild animals blood.

    PubMed

    Mauricio, Claudio R M; Schneider, Fabio K; Dos Santos, Leonilda Correia

    2010-01-01

    An image-based red blood cell (RBC) automatic counting system is presented for wild animals blood analysis. Images with 2048×1536-pixel resolution acquired on an optical microscope using Neubauer chambers are used to evaluate RBC counting for three animal species (Leopardus pardalis, Cebus apella and Nasua nasua) and the error found using the proposed method is similar to that obtained for inter observer visual counting method, i.e., around 10%. Smaller errors (e.g., 3%) can be obtained in regions with less grid artifacts. These promising results allow the use of the proposed method either as a complete automatic counting tool in laboratories for wild animal's blood analysis or as a first counting stage in a semi-automatic counting tool.

  8. Mobility Enhancement of Red Blood Cells with Biopolymers

    NASA Astrophysics Data System (ADS)

    Tahara, Daiki; Oikawa, Noriko; Kurita, Rei

    2016-03-01

    Adhesion of red blood cells (RBC) to substrates are one of crucial problems for a blood clot. Here we investigate the mobility of RBC between two glass substrates in saline with polymer systems. We find that RBCs are adhered to the glass substrate with PEG, however the mobility steeply increases with fibrinogen and dextran, which are biopolymers. We also find that the mobility affects an aggregation dynamics of RBCs, which is related with diseases such as influenza, blood clot and so on. The Brownian motion helps to increase probability of contact with each other and to find a more stable condition of the aggregation. Thus the biopolymers play important roles not only for preventing the adhesion but also for the aggregation.

  9. [Simplified preparation of test-red blood cells for ABO blood grouping in a laboratory in Madagascar].

    PubMed

    Rasamiravaka, T; Andrianarivelo, A M; Ramarison, G; Rakoto-Alson, A O; Rasamindrakotroka, A

    2011-10-01

    To ensure self-sufficiency and lower costs associated with reagent red blood cells, some medical laboratories produce their own test-red blood cells for plasma ABO blood grouping. However, given the vital importance of blood goup testing, it is essential to verify the reliability of these cells. The purpose of this study was to assess the quality of laboratory-made ABO test-red blood cells. This study comparing house made and commercially available test-red blood cells was carried out at the Medical Biology Training and Research Laboratory in Madagascar. This laboratory is attended by people wishing to obtain their blood group card. In this population, no discrepancy was found between the red cell and plasma tests. Comparison of test-red blood cells with commercially available reagent red blood cells showed no difference in reactivity in the first four days of conservation. However a decrease in the reactivity of house made cells appeared on the 5th day. House made red blood cells are costless than commercially available reagent red blood cells mainly due to the simplified method of preparation. However, since laboratory-made cells progressivley lose antigenic reactivity quicly, production must be repeated regularly and good internal quality control is necessary to ensure reliability.

  10. Red blood cell transfusion for people undergoing hip fracture surgery.

    PubMed

    Brunskill, Susan J; Millette, Sarah L; Shokoohi, Ali; Pulford, E C; Doree, Carolyn; Murphy, Michael F; Stanworth, Simon

    2015-04-21

    The incidence of hip fracture is increasing and it is more common with increasing age. Surgery is used for almost all hip fractures. Blood loss occurs as a consequence of both the fracture and the surgery and thus red blood cell transfusion is frequently used. However, red blood cell transfusion is not without risks. Therefore, it is important to identify the evidence for the effective and safe use of red blood cell transfusion in people with hip fracture. To assess the effects (benefits and harms) of red blood cell transfusion in people undergoing surgery for hip fracture. We searched the Cochrane Bone, Joint and Muscle Trauma Group Specialised Register (31 October 2014), the Cochrane Central Register of Controlled Trials (The Cochrane Library, 2014, Issue 10), MEDLINE (January 1946 to 20 November 2014), EMBASE (January 1974 to 20 November 2014), CINAHL (January 1982 to 20 November 2014), British Nursing Index Database (January 1992 to 20 November 2014), the Systematic Review Initiative's Transfusion Evidence Library, PubMed for e-publications, various other databases and ongoing trial registers. Randomised controlled trials comparing red blood cell transfusion versus no transfusion or an alternative to transfusion, different transfusion protocols or different transfusion thresholds in people undergoing surgery for hip fracture. Three review authors independently assessed each study's risk of bias and extracted data using a study-specific form. We pooled data where there was homogeneity in the trial comparisons and the timing of outcome measurement. We used GRADE criteria to assess the quality (low, moderate or high) of the evidence for each outcome. We included six trials (2722 participants): all compared two thresholds for red blood cell transfusion: a 'liberal' strategy to maintain a haemoglobin concentration of usually 10 g/dL versus a more 'restrictive' strategy based on symptoms of anaemia or a lower haemoglobin concentration, usually 8 g/dL. The exact

  11. Quality of red blood cells isolated from umbilical cord blood stored at room temperature.

    PubMed

    Zhurova, Mariia; Akabutu, John; Acker, Jason

    2012-01-01

    Red blood cells (RBCs) from cord blood contain fetal hemoglobin that is predominant in newborns and, therefore, may be more appropriate for neonatal transfusions than currently transfused adult RBCs. Post-collection, cord blood can be stored at room temperature for several days before it is processed for stem cells isolation, with little known about how these conditions affect currently discarded RBCs. The present study examined the effect of the duration cord blood spent at room temperature and other cord blood characteristics on cord RBC quality. RBCs were tested immediately after their isolation from cord blood using a broad panel of quality assays. No significant decrease in cord RBC quality was observed during the first 65 hours of storage at room temperature. The ratio of cord blood to anticoagulant was associated with RBC quality and needs to be optimized in future. This knowledge will assist in future development of cord RBC transfusion product.

  12. Quality of Red Blood Cells Isolated from Umbilical Cord Blood Stored at Room Temperature

    PubMed Central

    Zhurova, Mariia; Akabutu, John; Acker, Jason

    2012-01-01

    Red blood cells (RBCs) from cord blood contain fetal hemoglobin that is predominant in newborns and, therefore, may be more appropriate for neonatal transfusions than currently transfused adult RBCs. Post-collection, cord blood can be stored at room temperature for several days before it is processed for stem cells isolation, with little known about how these conditions affect currently discarded RBCs. The present study examined the effect of the duration cord blood spent at room temperature and other cord blood characteristics on cord RBC quality. RBCs were tested immediately after their isolation from cord blood using a broad panel of quality assays. No significant decrease in cord RBC quality was observed during the first 65 hours of storage at room temperature. The ratio of cord blood to anticoagulant was associated with RBC quality and needs to be optimized in future. This knowledge will assist in future development of cord RBC transfusion product. PMID:24089645

  13. Expression of blood group antigens on red cell microvesicles.

    PubMed

    Oreskovic, R T; Dumaswala, U J; Greenwalt, T J

    1992-01-01

    The purpose of this study was to determine whether epitopes of the A, B, D, Fya, M, N, S, s, and K blood group antigens are present on microvesicle membranes shed by red cells during storage. Vesicles were isolated from outdated units of blood having and lacking the specified antigens. Diluted antisera were absorbed with fixed quantities of vesicles from red cells with the test antigen and red cells lacking that antigen (controls). The adsorbed and unadsorbed antisera were titrated and scored by using panel cells from persons known to be heterozygous for all the non-AB antigens. The mean titration scores following adsorption with the vesicles from A, B, D, M+N-, M-N+, S+s-, S-s+, and Fy(a+b-) units were appreciably lower than the control scores (0, 0, 3, 2, 2, 0, 4, and 4 vs. 19, 23, 34, 13, 12, 16, 18, and 29, respectively), which indicated the presence of these epitopes on the membrane of shed vesicles. The results following adsorption with K:1,2 vesicles were equivocal.

  14. Utilization and quality of cryopreserved red blood cells in transfusion medicine.

    PubMed

    Henkelman, S; Noorman, F; Badloe, J F; Lagerberg, J W M

    2015-02-01

    Cryopreserved (frozen) red blood cells have been used in transfusion medicine since the Vietnam war. The main method to freeze the red blood cells is by usage of glycerol. Although the usage of cryopreserved red blood cells was promising due to the prolonged storage time and the limited cellular deterioration at subzero temperatures, its usage have been hampered due to the more complex and labour intensive procedure and the limited shelf life of thawed products. Since the FDA approval of a closed (de) glycerolization procedure in 2002, allowing a prolonged postthaw storage of red blood cells up to 21 days at 2-6°C, cryopreserved red blood cells have become a more utilized blood product. Currently, cryopreserved red blood cells are mainly used in military operations and to stock red blood cells with rare phenotypes. Yet, cryopreserved red blood cells could also be useful to replenish temporary blood shortages, to prolong storage time before autologous transfusion and for IgA-deficient patients. This review describes the main methods to cryopreserve red blood cells, explores the quality of this blood product and highlights clinical settings in which cryopreserved red blood cells are or could be utilized.

  15. Method and kit for the selective labeling of red blood cells in whole blood with Tc-99m

    DOEpatents

    Srivastava, S.C.; Babich, J.W.; Straub, R.; Richards, P.

    1988-07-05

    Disclosed herein are a method and kit for the preparation of [sup 99m]Tc labeled red blood cells using whole blood in a closed sterile system containing stannous tin in a form such that it will enter the red blood cells and be available for the reduction of technetium. No Drawings

  16. Method and kit for the selective labeling of red blood cells in whole blood with TC-99M

    DOEpatents

    Srivastava, Suresh C.; Babich, John W.; Straub, Rita; Richards, Powell

    1988-01-01

    Disclosed herein are a method and kit for the preparation of .sup.99m Tc labeled red blood cells using whole blood in a closed sterile system containing stannous tin in a form such that it will enter the red blood cells and be available therein for the reduction of technetium.

  17. Flow of Red Blood Cells in Stenosed Microvessels

    PubMed Central

    Vahidkhah, Koohyar; Balogh, Peter; Bagchi, Prosenjit

    2016-01-01

    A computational study is presented on the flow of deformable red blood cells in stenosed microvessels. It is observed that the Fahraeus-Lindqvist effect is significantly enhanced due to the presence of a stenosis. The apparent viscosity of blood is observed to increase by several folds when compared to non-stenosed vessels. An asymmetric distribution of the red blood cells, caused by geometric focusing in stenosed vessels, is observed to play a major role in the enhancement. The asymmetry in cell distribution also results in an asymmetry in average velocity and wall shear stress along the length of the stenosis. The discrete motion of the cells causes large time-dependent fluctuations in flow properties. The root-mean-square of flow rate fluctuations could be an order of magnitude higher than that in non-stenosed vessels. Several folds increase in Eulerian velocity fluctuation is also observed in the vicinity of the stenosis. Surprisingly, a transient flow reversal is observed upstream a stenosis but not downstream. The asymmetry and fluctuations in flow quantities and the flow reversal would not occur in absence of the cells. It is concluded that the flow physics and its physiological consequences are significantly different in micro- versus macrovascular stenosis. PMID:27319318

  18. Flow of Red Blood Cells in Stenosed Microvessels

    NASA Astrophysics Data System (ADS)

    Vahidkhah, Koohyar; Balogh, Peter; Bagchi, Prosenjit

    2016-06-01

    A computational study is presented on the flow of deformable red blood cells in stenosed microvessels. It is observed that the Fahraeus-Lindqvist effect is significantly enhanced due to the presence of a stenosis. The apparent viscosity of blood is observed to increase by several folds when compared to non-stenosed vessels. An asymmetric distribution of the red blood cells, caused by geometric focusing in stenosed vessels, is observed to play a major role in the enhancement. The asymmetry in cell distribution also results in an asymmetry in average velocity and wall shear stress along the length of the stenosis. The discrete motion of the cells causes large time-dependent fluctuations in flow properties. The root-mean-square of flow rate fluctuations could be an order of magnitude higher than that in non-stenosed vessels. Several folds increase in Eulerian velocity fluctuation is also observed in the vicinity of the stenosis. Surprisingly, a transient flow reversal is observed upstream a stenosis but not downstream. The asymmetry and fluctuations in flow quantities and the flow reversal would not occur in absence of the cells. It is concluded that the flow physics and its physiological consequences are significantly different in micro- versus macrovascular stenosis.

  19. Blood

    MedlinePlus

    ... The liquid part, called plasma, is made of water, salts, and protein. Over half of your blood is plasma. The solid part of your blood contains red blood cells, white blood cells, and platelets. Red ...

  20. Phosphatidylserine exposure on stored red blood cells as a parameter for donor-dependent variation in product quality.

    PubMed

    Dinkla, Sip; Peppelman, Malou; Van Der Raadt, Jori; Atsma, Femke; Novotný, Vera M J; Van Kraaij, Marian G J; Joosten, Irma; Bosman, Giel J C G M

    2014-04-01

    Exposure of phosphatidylserine on the outside of red blood cells contributes to recognition and removal of old and damaged cells. The fraction of phosphatidylserine-exposing red blood cells varies between donors, and increases in red blood cell concentrates during storage. The susceptibility of red blood cells to stress-induced phosphatidylserine exposure increases with storage. Phosphatidylserine exposure may, therefore, constitute a link between donor variation and the quality of red blood cell concentrates. In order to examine the relationship between storage parameters and donor characteristics, the percentage of phosphatidylserine-exposing red blood cells was measured in red blood cell concentrates during storage and in fresh red blood cells from blood bank donors. The percentage of phosphatidylserine-exposing red blood cells was compared with red blood cell susceptibility to osmotic stress-induced phosphatidylserine exposure in vitro, with the regular red blood cell concentrate quality parameters, and with the donor characteristics age, body mass index, haemoglobin level, gender and blood group. Phosphatidylserine exposure varies between donors, both on red blood cells freshly isolated from the blood, and on red blood cells in red blood cell concentrates. Phosphatidylserine exposure increases with storage time, and is correlated with stress-induced phosphatidylserine exposure. Increased phosphatidylserine exposure during storage was found to be associated with haemolysis and vesicle concentration in red blood cell concentrates. The percentage of phosphatidylserine-exposing red blood cells showed a positive correlation with the plasma haemoglobin concentration of the donor. The fraction of phosphatidylserine-exposing red blood cells is a parameter of red blood cell integrity in red blood cell concentrates and may be an indicator of red blood cell survival after transfusion. Measurement of phosphatidylserine exposure may be useful in the selection of donors and

  1. Clustering of red blood cells using digital holographic microscopy

    NASA Astrophysics Data System (ADS)

    Jaferzadeh, K.; Ahmadzadeh, E.; Moon, I.; Gholami, S.

    2017-05-01

    Digital holographic microscopy can provide quantitative phase images (QPIs) of 3D profile of red blood cell (RBC) with nanometer accuracy. In this paper we propose applying k-means clustering method to cluster RBCs into two groups of young and old RBCs by using a four-dimensional feature vector. The features are RBC thickness average, surface area-volume ratio, sphericity coefficient and RBC perimeter that can be obtained from QPIs. The proposed features are related to the morphology of RBC. The experimental result shows that by utilizing the proposed method two groups of sphero-echinocytes (old RBCs) and non-spheroechinocytes RBCs can be perfectly clustered.

  2. Nanomechanical characterization of red blood cells using optical tweezers.

    PubMed

    Li, Chuan; Liu, K K

    2008-04-01

    Deformation behaviours of red blood cells (RBCs) have been studied by applying stretching forces via optical tweezers. Combined with finite-element analyses (FEA), the RBCs' mechanical properties are determined quantitatively based on a best fitting between the experimental deformed geometries and the simulated counterparts. Experimentally, a silica beads attached erythrocyte is optical-mechanically stretched to different lengths. On the theoretical front, a large deformation model with Mooney-Rivlin constitutive equations has been simulated by using FEA to predict the cell deformation geometries. The numerically simulated transverse and longitudinal strains which are in a good agreement with the experimental measurements facilitate the determination of elastic constants of the cells.

  3. Red Blood Cell Membrane-Cloaked Nanoparticles For Drug Delivery

    NASA Astrophysics Data System (ADS)

    Carpenter, Cody Westcott

    Herein we describe the development of the Red Blood Cell coated nanoparticle, RBC-NP. Purified natural erythrocyte membrane is used to coat drug-loaded poly(lacticco-glycolic acid) (PLGA). Synthetic PLGA co-polymer is biocompatible and biodegradable and has already received US FDA approval for drug-delivery and diagnostics. This work looks specifically at the retention of immunosuppressive proteins on RBC-NPs, right-sidedness of natural RBC membranes interfacing with synthetic polymer nanoparticles, sustained and retarded drug release of RBC-NPs as well as further surface modification of RBC-NPs for increased targeting of model cancer cell lines.

  4. Multiscale Modeling of Red Blood Cells Squeezing through Submicron Slits

    NASA Astrophysics Data System (ADS)

    Peng, Zhangli; Lu, Huijie

    2016-11-01

    A multiscale model is applied to study the dynamics of healthy red blood cells (RBCs), RBCs in hereditary spherocytosis, and sickle cell disease squeezing through submicron slits. This study is motivated by the mechanical filtration of RBCs by inter-endothelial slits in the spleen. First, the model is validated by comparing the simulation results with experiments. Secondly, the deformation of the cytoskeleton in healthy RBCs is investigated. Thirdly, the mechanisms of damage in hereditary spherocytosis are investigated. Finally, the effects of cytoplasm and membrane viscosities, especially in sickle cell disease, are examined. The simulations results provided guidance for future experiments to explore the dynamics of RBCs under extreme deformation.

  5. Cytoskeleton confinement and tension of red blood cell membranes.

    PubMed

    Gov, N; Zilman, A G; Safran, S

    2003-06-06

    We analyze theoretically both the static and dynamic fluctuation spectra of the red blood cell in a unified manner, using a simple model of the composite membrane. In this model, the two-dimensional spectrin network that forms the cytoskeleton is treated as a rigid shell, located at a fixed, average distance from the lipid bilayer. The cytoskeleton thereby confines both the static and dynamic fluctuations of the lipid bilayer. The sparse connections of the cytoskeleton and bilayer induce a surface tension, for wavelengths larger than the bilayer persistence length. The predictions of the model give a consistent account for both the wave vector and frequency dependence of the experimental data.

  6. Home improvements: malaria and the red blood cell.

    PubMed

    Foley, M; Tilley, L

    1995-11-01

    In real-estate agent's terms, the red blood cell is a renovator's dream. The mature human erythrocyte has no internal organelles, no protein synthesis machinery and no infrastructure for protein trafficking. The malaria parasite invades this empty shell and effectively converts the erythrocyte back into a fully functional eukaryotic cell. In this article, Michael Foley and Leann Tilley examine the Plasmodium falciparum proteins that interact with the membrane skeleton at different stages of the infection and speculate on the roles of these proteins in the remodelling process.

  7. Red blood cell adhesion on a solid/liquid interface

    PubMed Central

    Lavalle, Ph.; Stoltz, J.-F.; Senger, B.; Voegel, J.-C.; Schaaf, P.

    1996-01-01

    Red blood cells (RBCs), previously fixed with glutaraldehyde, adhere to glass slides coated with fibrinogen. The RBC deposition process on the horizontal glass surface is investigated by analyzing the relative surface covered by the RBCs, as well as the variance of this surface coverage, as a function of the concentration of particles. This study is performed by optical microscopy and image analysis. A model, derived from the classical random sequential adsorption model, has been developed to account for the experimental results. This model highlights the strong influence of the hydrodynamic interactions during the deposition process. PMID:8986776

  8. The nature of multiphoton fluorescence from red blood cells

    NASA Astrophysics Data System (ADS)

    Saytashev, Ilyas; Murphy, Michael; Osseiran, Sam; Spence, Dana M.; Evans, Conor L.; Dantus, Marcos

    2016-03-01

    We report on the nature of multiphoton excited fluorescence observed from human erythrocytes (red blood cells RBC's) and their "ghosts" following 800nm sub-15 fs excitation. The detected optical signal is assigned as two-photon excited fluorescence from hemoglobin. Our findings are supported by wavelength-resolved fluorescence lifetime decay measurements using time-correlated single photon counting system from RBC's, their ghosts as well as in vitro samples of various fluorophores including riboflavin, NADH, NAD(P)H, hemoglobin. We find that low-energy and short-duration pulses allow two-photon imaging of RBC's, but longer more intense pulses lead to their destruction.

  9. Photoacoustic tomography of unlabelled red blood cell at the nanoscale

    NASA Astrophysics Data System (ADS)

    Samant, Pratik; Chen, Jian; Xiang, Liangzhong

    2016-09-01

    In this letter, we present the principle behind nanoscale photoacoustic tomography (nPAT), in addition to simulation results demonstrating the thermal safety and the diagnostic potential of such a modality. Nanoscale photoacoustic tomography is a novel biomedical imaging modality that can allow for the 3D imaging of cells at nanometer resolutions. This modality also allows for the imaging of single red blood cells (RBCs) such that the hemoglobin concentration quantities can be visualized within the cell. As a result, we believe that nPAT can allow for diagnostic information at unprecedented resolutions and enable the visualization of previously unseen phenomenon in RBCs.

  10. Measuring skewness of red blood cell deformability distribution by laser ektacytometry

    NASA Astrophysics Data System (ADS)

    Nikitin, S. Yu; Priezzhev, A. V.; Lugovtsov, A. E.; Ustinov, V. D.

    2014-08-01

    An algorithm is proposed for measuring the parameters of red blood cell deformability distribution based on laser diffractometry of red blood cells in shear flow (ektacytometry). The algorithm is tested on specially prepared samples of rat blood. In these experiments we succeeded in measuring the mean deformability, deformability variance and skewness of red blood cell deformability distribution with errors of 10%, 15% and 35%, respectively.

  11. Measuring skewness of red blood cell deformability distribution by laser ektacytometry

    SciTech Connect

    Nikitin, S Yu; Priezzhev, A V; Lugovtsov, A E; Ustinov, V D

    2014-08-31

    An algorithm is proposed for measuring the parameters of red blood cell deformability distribution based on laser diffractometry of red blood cells in shear flow (ektacytometry). The algorithm is tested on specially prepared samples of rat blood. In these experiments we succeeded in measuring the mean deformability, deformability variance and skewness of red blood cell deformability distribution with errors of 10%, 15% and 35%, respectively. (laser biophotonics)

  12. Photodynamic treatment of red blood cell concentrates for virus inactivation enhances red blood cell aggregation: protection with antioxidants.

    PubMed

    Ben-Hur, E; Barshtein, G; Chen, S; Yedgar, S

    1997-10-01

    Photodynamic treatment (PDT) using phthalocyanines and red light appears to be a promising procedure for decontamination of red blood cell (RBC) concentrates for transfusion. A possible complication of this treatment may be induced aggregation of RBC. The production of RBC aggregates was measured with a novel computerized cell flow properties analyzer (CFA). The PDT of RBC concentrates with sulfonated aluminum phthalocyanine (AIPcS4) and the silicon phthalocyanine Pc 4 under virucidal conditions markedly enhanced RBC aggregation and higher shear stress was required to disperse these aggregates. The clusters of cells were huge and abnormally shaped, unlike the rouleaux formed by untreated RBC. This aggregation was prevented when a mixture of antioxidants was included during PDT. Addition of the antioxidants after PDT reduced aggregation only partially. It is concluded that inclusion of antioxidants during PDT of RBC concentrates prior to transfusion may reduce or eliminate the hemodynamic risk that the virucidal treatment may present to the recipient.

  13. SEM analysis of red blood cells in aged human bloodstains.

    PubMed

    Hortolà, P

    1992-08-01

    Mammal red blood cells (RBC) in bloodstains have been previously detected by light microscopy on stone tools from as early as 100,000 +/- 25,000 years ago. In order to evaluate the degree of morphological preservation of erythrocytes in bloodstains, an accidental human blood smear on white chert and several experimental bloodstains on hard substrates (the same stone-white chert; another type of stone-graywacke; a non-stone support-stainless steel), were stored in a room, in non-sterile and fluctuating conditions, for lengths of time ranging from 3 to 18 months. Afterwards, the specimens were coated with gold and examined by a Cambridge Stereoscan 120 scanning electron microscope. Results revealed a high preservation of RBC integrity, with the maintenance of several discocytary shapes, a low tendency to echinocytosis and a frequent appearance of a moon-like erythrocytary shape in the thinner areas of the bloodstains.

  14. Automatic tracking of labeled red blood cells in microchannels.

    PubMed

    Pinho, Diana; Lima, Rui; Pereira, Ana I; Gayubo, Fernando

    2013-09-01

    The current study proposes an automatic method for the segmentation and tracking of red blood cells flowing through a 100- μm glass capillary. The original images were obtained by means of a confocal system and then processed in MATLAB using the Image Processing Toolbox. The measurements obtained with the proposed automatic method were compared with the results determined by a manual tracking method. The comparison was performed by using both linear regressions and Bland-Altman analysis. The results have shown a good agreement between the two methods. Therefore, the proposed automatic method is a powerful way to provide rapid and accurate measurements for in vitro blood experiments in microchannels. Copyright © 2012 John Wiley & Sons, Ltd.

  15. Vesicles, capsules and red blood cells under flow

    NASA Astrophysics Data System (ADS)

    Misbah, Chaouqi

    2012-12-01

    Blood flow is dictated by the dynamics of red blood cells (RBCs), which constitute by far the major component. RBCs are made of a a two dimensional fluid bilayer of phospholipids, having underneath a network of proteins conferring to them shear elasticity, and they possess many membrane and transmembrane proteins (like ion channels). Simplified systems, like vesicles (made of a pure bilayer of phospholipid) and capsules (made of an extensible polymer shell) are used as models for RBCs. Both systems reproduce several features known for RBCs under flow. Their interest lies, besides some simplicity, in the fact that they can be fabricated in the laboratory, and their properties (size, stiffness, internal content....) can be varied in a wide range allowing thus to explore a quite significant parameter space that is essential to test predictions and discriminate between different models. We shall review the main recent achievement in this field, both for a single entity, collective effects and the impact on rheology.

  16. Automatic analysis of microscopic images of red blood cell aggregates

    NASA Astrophysics Data System (ADS)

    Menichini, Pablo A.; Larese, Mónica G.; Riquelme, Bibiana D.

    2015-06-01

    Red blood cell aggregation is one of the most important factors in blood viscosity at stasis or at very low rates of flow. The basic structure of aggregates is a linear array of cell commonly termed as rouleaux. Enhanced or abnormal aggregation is seen in clinical conditions, such as diabetes and hypertension, producing alterations in the microcirculation, some of which can be analyzed through the characterization of aggregated cells. Frequently, image processing and analysis for the characterization of RBC aggregation were done manually or semi-automatically using interactive tools. We propose a system that processes images of RBC aggregation and automatically obtains the characterization and quantification of the different types of RBC aggregates. Present technique could be interesting to perform the adaptation as a routine used in hemorheological and Clinical Biochemistry Laboratories because this automatic method is rapid, efficient and economical, and at the same time independent of the user performing the analysis (repeatability of the analysis).

  17. Simulation of red blood cell aggregation in shear flow.

    PubMed

    Lim, B; Bascom, P A; Cobbold, R S

    1997-01-01

    A simulation model has been developed for red blood cell (RBC) aggregation in shear flow. It is based on a description of the collision rates of RBC, the probability of particles sticking together, and the breakage of aggregates by shear forces. The influence of shear rate, hematocrit, aggregate fractal dimension, and binding strength on aggregation kinetics were investigated and compared to other theoretical and experimental results. The model was used to simulate blood flow in a long large diameter tube under steady flow conditions at low Reynolds numbers. The time and spatial distribution of the state of aggregation are shown to be in qualitative agreement with previous B-mode ultrasound studies in which a central region of low echogenicity was noted. It is suggested that the model can provide a basis for interpreting prior measurements of ultrasound echogenicity and may help relate them to the local state of aggregation.

  18. Method using CO for extending the useful shelf-life of refrigerated red blood cells

    DOEpatents

    Bitensky, Mark W.

    1995-01-01

    Method using CO for extending the useful shelf-life of refrigerated red blood cells. Carbon monoxide is utilized for stabilizing hemoglobin in red blood cells to be stored at low temperature. Changes observed in the stored cells are similar to those found in normal red cell aging in the body, the extent thereof being directly related to the duration of refrigerated storage. Changes in cell buoyant density, vesiculation, and the tendency of stored cells to bind autologous IgG antibody directed against polymerized band 3 IgG, all of which are related to red blood cell senescence and increase with refrigerated storage time, have been substantially slowed when red blood cells are treated with CO. Removal of the carbon monoxide from the red blood cells is readily and efficiently accomplished by photolysis in the presence of oxygen so that the stored red blood cells may be safely transfused into a recipient.

  19. Method using CO for extending the useful shelf-life of refrigerated red blood cells

    DOEpatents

    Bitensky, M.W.

    1995-12-19

    A method is disclosed using CO for extending the useful shelf-life of refrigerated red blood cells. Carbon monoxide is utilized for stabilizing hemoglobin in red blood cells to be stored at low temperature. Changes observed in the stored cells are similar to those found in normal red cell aging in the body, the extent thereof being directly related to the duration of refrigerated storage. Changes in cell buoyant density, vesiculation, and the tendency of stored cells to bind autologous IgG antibody directed against polymerized band 3 IgG, all of which are related to red blood cell senescence and increase with refrigerated storage time, have been substantially slowed when red blood cells are treated with CO. Removal of the carbon monoxide from the red blood cells is readily and efficiently accomplished by photolysis in the presence of oxygen so that the stored red blood cells may be safely transfused into a recipient. 5 figs.

  20. Measurement of Retinal Blood Flow Using Fluorescently Labeled Red Blood Cells1,2,3

    PubMed Central

    Kornfield, Tess E.

    2015-01-01

    Abstract Blood flow is a useful indicator of the metabolic state of the retina. However, accurate measurement of retinal blood flow is difficult to achieve in practice. Most existing optical techniques used for measuring blood flow require complex assumptions and calculations. We describe here a simple and direct method for calculating absolute blood flow in vessels of all sizes in the rat retina. The method relies on ultrafast confocal line scans to track the passage of fluorescently labeled red blood cells (fRBCs). The accuracy of the blood flow measurements was verified by (1) comparing blood flow calculated independently using either flux or velocity combined with diameter measurements, (2) measuring total retinal blood flow in arterioles and venules, (3) measuring blood flow at vessel branch points, and (4) measuring changes in blood flow in response to hyperoxic and hypercapnic challenge. Confocal line scans oriented parallel and diagonal to vessels were used to compute fRBC velocity and to examine velocity profiles across the width of vessels. We demonstrate that these methods provide accurate measures of absolute blood flow and velocity in retinal vessels of all sizes. PMID:26082942

  1. Red Cell Properties after Different Modes of Blood Transportation

    PubMed Central

    Makhro, Asya; Huisjes, Rick; Verhagen, Liesbeth P.; Mañú-Pereira, María del Mar; Llaudet-Planas, Esther; Petkova-Kirova, Polina; Wang, Jue; Eichler, Hermann; Bogdanova, Anna; van Wijk, Richard; Vives-Corrons, Joan-Lluís; Kaestner, Lars

    2016-01-01

    Transportation of blood samples is unavoidable for assessment of specific parameters in blood of patients with rare anemias, blood doping testing, or for research purposes. Despite the awareness that shipment may substantially alter multiple parameters, no study of that extent has been performed to assess these changes and optimize shipment conditions to reduce transportation-related artifacts. Here we investigate the changes in multiple parameters in blood of healthy donors over 72 h of simulated shipment conditions. Three different anticoagulants (K3EDTA, Sodium Heparin, and citrate-based CPDA) for two temperatures (4°C and room temperature) were tested to define the optimal transportation conditions. Parameters measured cover common cytology and biochemistry parameters (complete blood count, hematocrit, morphological examination), red blood cell (RBC) volume, ion content and density, membrane properties and stability (hemolysis, osmotic fragility, membrane heat stability, patch-clamp investigations, and formation of micro vesicles), Ca2+ handling, RBC metabolism, activity of numerous enzymes, and O2 transport capacity. Our findings indicate that individual sets of parameters may require different shipment settings (anticoagulants, temperature). Most of the parameters except for ion (Na+, K+, Ca2+) handling and, possibly, reticulocytes counts, tend to favor transportation at 4°C. Whereas plasma and intraerythrocytic Ca2+ cannot be accurately measured in the presence of chelators such as citrate and EDTA, the majority of Ca2+-dependent parameters are stabilized in CPDA samples. Even in blood samples from healthy donors transported using an optimized shipment protocol, the majority of parameters were stable within 24 h, a condition that may not hold for the samples of patients with rare anemias. This implies for as short as possible shipping using fast courier services to the closest expert laboratory at reach. Mobile laboratories or the travel of the patients to

  2. Non-invasive spectroscopy of transfusable red blood cells stored inside sealed plastic blood-bags.

    PubMed

    Buckley, K; Atkins, C G; Chen, D; Schulze, H G; Devine, D V; Blades, M W; Turner, R F B

    2016-03-07

    After being separated from (donated) whole blood, red blood cells are suspended in specially formulated additive solutions and stored (at 4 °C) in polyvinyl chloride (PVC) blood-bags until they are needed for transfusion. With time, the prepared red cell concentrate (RCC) is known to undergo biochemical changes that lower effectiveness of the transfusion, and thus regulations are in place that limit the storage period to 42 days. At present, RCC is not subjected to analytical testing prior to transfusion. In this study, we use Spatially Offset Raman Spectroscopy (SORS) to probe, non-invasively, the biochemistry of RCC inside sealed blood-bags. The retrieved spectra compare well with conventional Raman spectra (of sampled aliquots) and are dominated by features associated with hemoglobin. In addition to the analytical demonstration that SORS can be used to retrieve RCC spectra from standard clinical blood-bags without breaking the sterility of the system, the data reveal interesting detail about the oxygenation-state of the stored cells themselves, namely that some blood-bags unexpectedly contain measurable amounts of deoxygenated hemoglobin after weeks of storage. The demonstration that chemical information can be obtained non-invasively using spectroscopy will enable new studies of RCC degeneration, and points the way to a Raman-based instrument for quality-control in a blood-bank or hospital setting.

  3. Cytomegalovirus in Australian blood donors: seroepidemiology and seronegative red blood cell component inventories.

    PubMed

    Lancini, Daniel V; Faddy, Helen M; Ismay, Sue; Chesneau, Stuart; Hogan, Chris; Flower, Robert L

    2016-06-01

    Cytomegalovirus (CMV) can lead to severe disease in high-risk subpopulations. To prevent transfusion-transmitted CMV in these patient groups, the Australian Red Cross Blood Service maintains inventories of CMV-seronegative fresh blood components. Donor demographic data and CMV seroscreening results for all blood donations and blood components issued in Australia between financial years (FYs) 2008/09 to 2012/13 inclusive were obtained. Population estimates were also extracted for the calculation of age-weighted seroprevalence estimates. Linear regression was used to model trends in red blood cell (RBC) component acquisition and demand. The estimated age-weighted seroprevalence of CMV in 20- to 69-year old Australians was 76.12 ± 0.13%, with higher seroprevalence in females and older age groups. Seroprevalence decreased over the study period, while the demand for CMV-seronegative RBC components increased. It was predicted that component acquisition may be insufficient by FY 2017/18 if current trends persist. These findings represent an evaluation of CMV seroepidemiology in Australia and form a basis to predict the future status of CMV-seronegative RBC component inventories. The results will serve to guide Blood Service operations and inform current international debate on CMV-safe blood components. © 2016 AABB.

  4. [Evaluation of riboflavin photochemical inactivation efficacy of virus in red blood cells by using animal models].

    PubMed

    Yang, Peng; Zhang, Xun-Shan; Cheng, Yue; Zhao, Jun; Wang, Ming-Li

    2011-02-01

    This study was aimed to evaluate the efficacy of riboflavin photochemical inactivation of virus in red blood cells by using animal models. human cytomegalovirus (HCMV) plus red blood cells were used as indicator, 30 BALA/c mice were divided into the experimental group (n = 10), virus control group (n = 10), visible light control group (n = 5) and red blood cell control group (n = 5). Mice in experimental group were inoculated with red blood cells inactive by the riboflavin photochemical, mice in virus control group was injected with red blood cells without riboflavin photochemical inactivation treatment, and mice in light control group was infused with red blood cells irradiated by visible light, and mice in red blood cells control group was injected with normal red blood cells. The virus was isolated in vitro from mice of various groups, the HCMV UL83 gene was detected by PCR, the PP65 antigen was identified by indirect immunofluorescence. The results indicated that the virus isolation, PCR detection and indirect immunofluorescence identification all showed positive in virus control group and visible light control group, while the results of detection in experimental and red blood cell control groups were negative. It is concluded that riboflavin photochemical viral inactivation of red blood cells is effective.

  5. Attenuation of Red Blood Cell Storage Lesions with Vitamin C.

    PubMed

    Sanford, Kimberly; Fisher, Bernard J; Fowler, Evan; Fowler, Alpha A; Natarajan, Ramesh

    2017-07-12

    Stored red blood cells (RBCs) undergo oxidative stress that induces deleterious metabolic, structural, biochemical, and molecular changes collectively referred to as "storage lesions". We hypothesized that vitamin C (VitC, reduced or oxidized) would reduce red cell storage lesions, thus prolonging their storage duration. Whole-blood-derived, leuko-reduced, SAGM (saline-adenine-glucose-mannitol)-preserved RBC concentrates were equally divided into four pediatric storage bags and the following additions made: (1) saline (saline); (2) 0.3 mmol/L reduced VitC (Lo VitC); (3) 3 mmol/L reduced VitC (Hi VitC); or (4) 0.3 mmol/L oxidized VitC (dehydroascorbic acid, DHA) as final concentrations. Biochemical and rheological parameters were serially assessed at baseline (prior to supplementation) and Days 7, 21, 42, and 56 for RBC VitC concentration, pH, osmotic fragility by mechanical fragility index, and percent hemolysis, LDH release, glutathione depletion, RBC membrane integrity by scanning electron microscopy, and Western blot for β-spectrin. VitC exposure (reduced and oxidized) significantly increased RBC antioxidant status with varying dynamics and produced trends in reduction in osmotic fragility and increases in membrane integrity. VitC partially protects RBC from oxidative changes during storage. Combining VitC with other antioxidants has the potential to improve long-term storage of RBC.

  6. Tension of red blood cell membrane in simple shear flow.

    PubMed

    Omori, T; Ishikawa, T; Barthès-Biesel, D; Salsac, A-V; Imai, Y; Yamaguchi, T

    2012-11-01

    When a red blood cell (RBC) is subjected to an external flow, it is deformed by the hydrodynamic forces acting on its membrane. The resulting elastic tensions in the membrane play a key role in mechanotransduction and govern its rupture in the case of hemolysis. In this study, we analyze the motion and deformation of an RBC in a simple shear flow and the resulting elastic tensions on the membrane. The large deformation of the red blood cell is modelled by coupling a finite element method to solve the membrane mechanics and a boundary element method to solve the flows of the internal and external liquids. Depending on the capillary number Ca, ratio of the viscous to elastic forces, we observe three kinds of RBC motion: tumbling at low Ca, swinging at larger Ca, and breathing at the transitions. In the swinging regime, the region of the high principal tensions periodically oscillates, whereas that of the high isotropic tensions is almost unchanged. Due to the strain-hardening property of the membrane, the deformation is limited but the membrane tension increases monotonically with the capillary number. We have quantitatively compared our numerical results with former experimental results. It indicates that a membrane isotropic tension O(10{-6} N/m) is high enough for molecular release from RBCs and that the typical maximum membrane principal tension for haemolysis would be O(10{-4} N/m). These findings are useful to clarify not only the membrane rupture but also the mechanotransduction of RBCs.

  7. Vibrational modes of hemoglobin in red blood cells.

    PubMed

    Martel, P; Calmettes, P; Hennion, B

    1991-02-01

    Equine red blood cells were washed in saline heavy water (2H2O) to exchange the hydrogen atoms of the non-hemoglobin components with deuterons. This led to novel neutron scattering measurements of protein vibrations within a cellular system and permitted a comparison with inelastic neutron scattering measurements on purified horse hemoglobin, either dry or wetted with 2H2O. As a function of wavevector transfer Q and the frequency transfer v the neutron response typified by the dynamic structure factor S(Q, v) was found to be similar for extracted and cellular hemoglobin at low and high temperatures. At 77 K, in the cells, a peak in S(Q, v) due to the protein was found near 0.7 THz, approximately half the frequency of a strong peak in the aqueous medium. Measurements at higher temperatures (170 and 230 K) indicated similar small shifts downwards in the peak frequencies of both components. At 260 K the low frequency component became predominantly quasielastic, but a significant inelastic component could still be ascribed to the aqueous scattering. Near 295 K the frequency responses of both components were similar and centered near zero. When scattering due to water is taken into account it appears that the protein neutron response in, or out of, red blood cells is little affected by hydration in the low frequency regime where Van der Waals forces are thought to be effective.

  8. Vibrational modes of hemoglobin in red blood cells.

    PubMed Central

    Martel, P; Calmettes, P; Hennion, B

    1991-01-01

    Equine red blood cells were washed in saline heavy water (2H2O) to exchange the hydrogen atoms of the non-hemoglobin components with deuterons. This led to novel neutron scattering measurements of protein vibrations within a cellular system and permitted a comparison with inelastic neutron scattering measurements on purified horse hemoglobin, either dry or wetted with 2H2O. As a function of wavevector transfer Q and the frequency transfer v the neutron response typified by the dynamic structure factor S(Q, v) was found to be similar for extracted and cellular hemoglobin at low and high temperatures. At 77 K, in the cells, a peak in S(Q, v) due to the protein was found near 0.7 THz, approximately half the frequency of a strong peak in the aqueous medium. Measurements at higher temperatures (170 and 230 K) indicated similar small shifts downwards in the peak frequencies of both components. At 260 K the low frequency component became predominantly quasielastic, but a significant inelastic component could still be ascribed to the aqueous scattering. Near 295 K the frequency responses of both components were similar and centered near zero. When scattering due to water is taken into account it appears that the protein neutron response in, or out of, red blood cells is little affected by hydration in the low frequency regime where Van der Waals forces are thought to be effective. PMID:1849028

  9. Effects of ethanol on red blood cell rheological behavior.

    PubMed

    Rabai, M; Detterich, J A; Wenby, R B; Toth, K; Meiselman, H J

    2014-01-01

    Consumption of red wine is associated with a decreased risk of several cardiovascular diseases (e.g., coronary artery disease, stroke), but unfortunately literature reports regarding ethanol's effects on hemorheological parameters are not concordant. In the present study, red blood cell (RBC) deformability was tested via laser ektacytometry (LORCA, 0.3-30 Pa) using two approaches: 1) addition of ethanol to whole blood at 0.25%-2% followed by incubation and testing in ethanol-free LORCA medium; 2) addition of ethanol to the LORCA medium at 0.25%-6% then testing untreated native RBC in these media. The effects of ethanol on deformability for oxidatively stressed RBC were investigated as were changes of RBC aggregation (Myrenne Aggregometer) for cells in autologous plasma or 3% 70 kDa dextran. Significant dose-related increases of RBC deformability were observed at 0.25% (p < 0.05) and higher concentrations only if ethanol was in the LORCA medium; no changes occurred for cells previously incubated with ethanol then tested in ethanol-free medium. The impaired deformability of cells pre-exposed to oxidative stress was improved only if ethanol was in the LORCA medium. RBC aggregation decreased with concentration at 0.25% and higher for cells in both autologous plasma and dextran 70. Our results indicate that ethanol reversibly improves erythrocyte deformability and irreversibly decreases erythrocyte aggregation; the relevance of these results to the health benefits of moderate wine consumption require further investigation.

  10. Challenges for red blood cell biomarker discovery through proteomics.

    PubMed

    Barasa, Benjamin; Slijper, Monique

    2014-05-01

    Red blood cells are rather unique body cells, since they have lost all organelles when mature, which results in lack of potential to replace proteins that have lost their function. They maintain only a few pathways for obtaining energy and reducing power for the key functions they need to fulfill. This makes RBCs highly sensitive to any aberration. If so, these RBCs are quickly removed from circulation, but if the RBC levels reduce extremely fast, this results in hemolytic anemia. Several causes of HA exist, and proteome analysis is the most straightforward way to obtain deeper insight into RBC functioning under the stress of disease. This should result in discovery of biomarkers, typical for each source of anemia. In this review, several challenges to generate in-depth RBC proteomes are described, like to obtain pure RBCs, to overcome the wide dynamic range in protein expression, and to establish which of the identified/quantified proteins are active in RBCs. The final challenge is to acquire and validate suited biomarkers unique for the changes that occur for each of the clinical questions; in red blood cell aging (also important for transfusion medicine), for thalassemias or sickle cell disease. Biomarkers for other hemolytic anemias that are caused by dysfunction of RBC membrane proteins (the RBC membrane defects) or RBC cytosolic proteins (the enzymopathies) are sometimes even harder to discover, in particular for the patients with RBC rare diseases with unknown cause. This article is part of a Special Issue entitled: Biomarkers: A Proteomic Challenge.

  11. Transport of diseased red blood cells in the spleen

    NASA Astrophysics Data System (ADS)

    Peng, Zhangli; Pivkin, Igor; Dao, Ming

    2012-11-01

    A major function of the spleen is to remove old and diseased red blood cells (RBCs) with abnormal mechanical properties. We investigated this mechanical filtering mechanism by combining experiments and computational modeling, especially for red blood cells in malaria and sickle cell disease (SCD). First, utilizing a transgenic line for 3D confocal live imaging, in vitro capillary assays and 3D finite element modeling, we extracted the mechanical properties of both the RBC membrane and malaria parasites for different asexual malaria stages. Secondly, using a non-invasive laser interferometric technique, we optically measured the dynamic membrane fluctuations of SCD RBCs. By simulating the membrane fluctuation experiment using the dissipative particle dynamics (DPD) model, we retrieved mechanical properties of SCD RBCs with different shapes. Finally, based on the mechanical properties obtained from these experiments, we simulated the full fluid-structure interaction problem of diseased RBCs passing through endothelial slits in the spleen under different fluid pressure gradients using the DPD model. The effects of the mechanical properties of the lipid bilayer, the cytoskeleton and the parasite on the critical pressure of splenic passage of RBCs were investigated separately. This work is supported by NIH and Singapore-MIT Alliance for Science and Technology (SMART).

  12. Reduction of prion infectivity in packed red blood cells

    SciTech Connect

    Morales, Rodrigo; Buytaert-Hoefen, Kimberley A.; Gonzalez-Romero, Dennisse; Castilla, Joaquin; Hansen, Eric T.; Hlavinka, Dennis; Goodrich, Raymond P.; Soto, Claudio

    2008-12-12

    The link between a new variant form of Creutzfeldt-Jakob disease (vCJD) and the consumption of prion contaminated cattle meat as well as recent findings showing that vCJD can be transmitted by blood transfusion have raised public health concerns. Currently, a reliable test to identify prions in blood samples is not available. The purpose of this study was to evaluate the possibility to remove scrapie prion protein (PrP{sup Sc}) and infectivity from red blood cell (RBC) suspensions by a simple washing procedure using a cell separation and washing device. The extent of prion removal was assessed by Western blot, PMCA and infectivity bioassays. Our results revealed a substantial removal of infectious prions ({>=}3 logs of infectivity) by all techniques used. These data suggest that a significant amount of infectivity present in RBC preparations can be removed by a simple washing procedure. This technology may lead to increased safety of blood products and reduce the risk of further propagation of prion diseases.

  13. Red blood cells as carriers in magnetic particle imaging.

    PubMed

    Antonelli, Antonella; Sfara, Carla; Rahmer, Jürgen; Gleich, Bernhard; Borgert, Jörn; Magnani, Mauro

    2013-12-01

    Red blood cells (RBCs) represent intravascular carriers for drugs, biologics, and other therapeutic agents, characterized by their unique longevity in the bloodstream, availability, considerable surface and volume, high biocompatibility, and natural mechanisms for safe elimination. Recently, the potential of RBCs loaded with superparamagnetic iron oxide (SPIO) nanoparticles as a tracer material for magnetic particle imaging (MPI) to realize a blood-pool tracer agent with longer blood retention time for imaging of the circulatory system, has been investigated. MPI is a new tomographic imaging approach that can quantitatively map magnetic nanoparticle distributions in vivo. However, SPIO contrast agents, such as Resovist, have a short blood half-life due to rapid uptake by the reticuloendothelial system, which limits the applicability of such compounds for certain applications such as long-term monitoring. Here, we report the in vitro magnetic characterization study of human SPIO-loaded RBCs and the first MPI results obtained after intravenous injection of murine SPIO-loaded RBCs in an in vivo MPI experiment.

  14. Dynamic deformability of sickle red blood cells in microphysiological flow.

    PubMed

    Alapan, Y; Matsuyama, Y; Little, J A; Gurkan, U A

    2016-06-01

    In sickle cell disease (SCD), hemoglobin molecules polymerize intracellularly and lead to a cascade of events resulting in decreased deformability and increased adhesion of red blood cells (RBCs). Decreased deformability and increased adhesion of sickle RBCs lead to blood vessel occlusion (vaso-occlusion) in SCD patients. Here, we present a microfluidic approach integrated with a cell dimensioning algorithm to analyze dynamic deformability of adhered RBC at the single-cell level in controlled microphysiological flow. We measured and compared dynamic deformability and adhesion of healthy hemoglobin A (HbA) and homozygous sickle hemoglobin (HbS) containing RBCs in blood samples obtained from 24 subjects. We introduce a new parameter to assess deformability of RBCs: the dynamic deformability index (DDI), which is defined as the time-dependent change of the cell's aspect ratio in response to fluid flow shear stress. Our results show that DDI of HbS-containing RBCs were significantly lower compared to that of HbA-containing RBCs. Moreover, we observed subpopulations of HbS containing RBCs in terms of their dynamic deformability characteristics: deformable and non-deformable RBCs. Then, we tested blood samples from SCD patients and analyzed RBC adhesion and deformability at physiological and above physiological flow shear stresses. We observed significantly greater number of adhered non-deformable sickle RBCs than deformable sickle RBCs at flow shear stresses well above the physiological range, suggesting an interplay between dynamic deformability and increased adhesion of RBCs in vaso-occlusive events.

  15. Zeroing in on red blood cell unit expiry.

    PubMed

    Ayyalil, Fathima; Irwin, Greg; Ross, Bryony; Manolis, Michael; Enjeti, Anoop K

    2017-09-20

    Expiry of red blood cell (RBC) units is a significant contributor to wastage of precious voluntary donations. Effective strategies aimed at optimal resource utilization are required to minimize wastage. This retrospective study analyzed the strategic measures implemented to reduce expiry of RBC units in an Australian tertiary regional hospital. The measures, which included inventory rearrangement, effective stock rotation, and the number of emergency courier services required during a 24-month period, were evaluated. There was no wastage of RBC units due to expiry over the 12 months after policy changes. Before these changes, approximately half of RBC wastage (261/511) was due to expiry. The total number of transfusions remained constant in this period and there was no increase in the use of emergency couriers. Policy changes implemented were decreasing the RBC inventory level by one-third and effective stock rotation and using a computerized system to link the transfusion services across the area. Effective stock rotation resulted in a reduction in older blood (>28 days) received in the main laboratory rotated from peripheral hospitals, down from 6%-41% to 0%-2.5%. Age-related expiry of blood products is preventable and can be significantly reduced by improving practices in the pathology service. This study provides proof of principle for "zero tolerance for RBC unit expiry" across a large networked blood banking service. © 2017 The Authors Transfusion published by Wiley Periodicals, Inc. on behalf of AABB.

  16. Simultaneous measurement of red blood cell aggregation and whole blood coagulation using high-frequency ultrasound.

    PubMed

    Nam, Kweon-Ho; Yeom, Eunseop; Ha, Hojin; Lee, Sang Joon

    2012-03-01

    This study aims to investigate the feasibility of using high-frequency ultrasound (HFUS) for simultaneous monitoring of blood coagulation and red blood cell (RBC) aggregation. Using a 35-MHz ultrasound scanner, ultrasound speckle data were acquired from whole blood samples of three experimental groups of rats, including 4,4'-diisothiocyanatostilbene-2,2'-disulfonic acid (DIDS)-treated, noncoagulation and normal control groups. The variations of blood echogenicity, the shape parameters of probability distribution of speckle intensity (skewness and kurtosis) and the correlation coefficient between two consecutive speckle data were calculated as a function of time starting from immediately after taking blood. The blood echogenicity increases rapidly to plateaus at the early stage of measurement for all the experimental groups caused by the formation of RBC aggregates. The DIDS-treated group exhibits the lowest echogenicity level due to the inhibitory effect of DIDS on RBC aggregation. The correlation analysis between consecutive speckle patterns seems to be useful to examine the variation of blood fluidity and the progress of clot formation. Whole blood coagulation is observed to be accelerated by DIDS treatment. In addition, the results of skewness and kurtosis analysis indicated that RBC aggregates may be disrupted during blood coagulation. The present study suggests that HFUS has good potential for simultaneous monitoring of RBC aggregation and blood coagulation to examine the relationship between them. Copyright © 2012 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

  17. The deformation behavior of multiple red blood cells in a capillary vessel.

    PubMed

    Gong, Xiaobo; Sugiyama, Kazuyasu; Takagi, Shu; Matsumoto, Yoichiro

    2009-07-01

    The deformation of multiple red blood cells in a capillary flow was studied numerically. The immersed boundary method was used for the fluid red blood cells interaction. The membrane of the red blood cell was modeled as a hyperelastic thin shell. The numerical results show that the apparent viscosity in the capillary flow is more sensitive to the change of shear coefficient of the membrane than the bending coefficient and surface dilation coefficient, and the increase in the shear coefficient results in an increase in the pressure drop in the blood flow in capillary vessels in order to sustain the same flux rate of red blood cells.

  18. Erythropoietin reduces storage lesions and decreases apoptosis indices in blood bank red blood cells.

    PubMed

    Penuela, Oscar Andrés; Palomino, Fernando; Gómez, Lina Andrea

    2016-01-01

    Recent evidence shows a selective destruction of the youngest circulating red blood cells (neocytolysis) trigged by a drop in erythropoietin levels. The aim of this study was to evaluate the effect of recombinant human erythropoietin beta on the red blood cell storage lesion and apoptosis indices under blood bank conditions. Each one of ten red blood cell units preserved in additive solution 5 was divided in two volumes of 100mL and assigned to one of two groups: erythropoietin (addition of 665IU of recombinant human erythropoietin) and control (isotonic buffer solution was added). The pharmacokinetic parameters of erythropoietin were estimated and the following parameters were measured weekly, for six weeks: Immunoreactive erythropoietin, hemolysis, percentage of non-discocytes, adenosine triphosphate, glucose, lactate, lactate dehydrogenase, and annexin-V/esterase activity. The t-test or Wilcoxon's test was used for statistical analysis with significance being set for a p-value <0.05. Erythropoietin, when added to red blood cell units, has a half-life >6 weeks under blood bank conditions, with persistent supernatant concentrations of erythropoietin during the entire storage period. Adenosine triphosphate was higher in the Erythropoietin Group in Week 6 (4.19±0.05μmol/L vs. 3.53±0.02μmol/L; p-value=0.009). The number of viable cells in the Erythropoietin Group was higher than in the Control Group (77%±3.8% vs. 71%±2.3%; p-value <0.05), while the number of apoptotic cells was lower (9.4%±0.3% vs. 22%±0.8%; p-value <0.05). Under standard blood bank conditions, an important proportion of red blood cells satisfy the criteria of apoptosis. Recombinant human erythropoietin beta seems to improve storage lesion parameters and mitigate apoptosis. Copyright © 2015 Associação Brasileira de Hematologia, Hemoterapia e Terapia Celular. Published by Elsevier Editora Ltda. All rights reserved.

  19. Erythropoietin reduces storage lesions and decreases apoptosis indices in blood bank red blood cells

    PubMed Central

    Penuela, Oscar Andrés; Palomino, Fernando; Gómez, Lina Andrea

    2015-01-01

    Background Recent evidence shows a selective destruction of the youngest circulating red blood cells (neocytolysis) trigged by a drop in erythropoietin levels. Objective The aim of this study was to evaluate the effect of recombinant human erythropoietin beta on the red blood cell storage lesion and apoptosis indices under blood bank conditions. Methods Each one of ten red blood cell units preserved in additive solution 5 was divided in two volumes of 100 mL and assigned to one of two groups: erythropoietin (addition of 665 IU of recombinant human erythropoietin) and control (isotonic buffer solution was added). The pharmacokinetic parameters of erythropoietin were estimated and the following parameters were measured weekly, for six weeks: Immunoreactive erythropoietin, hemolysis, percentage of non-discocytes, adenosine triphosphate, glucose, lactate, lactate dehydrogenase, and annexin-V/esterase activity. The t-test or Wilcoxon's test was used for statistical analysis with significance being set for a p-value <0.05. Results Erythropoietin, when added to red blood cell units, has a half-life >6 weeks under blood bank conditions, with persistent supernatant concentrations of erythropoietin during the entire storage period. Adenosine triphosphate was higher in the Erythropoietin Group in Week 6 (4.19 ± 0.05 μmol/L vs. 3.53 ± 0.02 μmol/L; p-value = 0.009). The number of viable cells in the Erythropoietin Group was higher than in the Control Group (77% ± 3.8% vs. 71% ± 2.3%; p-value <0.05), while the number of apoptotic cells was lower (9.4% ± 0.3% vs. 22% ± 0.8%; p-value <0.05). Conclusions Under standard blood bank conditions, an important proportion of red blood cells satisfy the criteria of apoptosis. Recombinant human erythropoietin beta seems to improve storage lesion parameters and mitigate apoptosis. PMID:26969770

  20. Isolation of nucleated red blood cells in maternal blood for Non-invasive prenatal diagnosis.

    PubMed

    Byeon, Yeongje; Ki, Chang-Seok; Han, Ki-Ho

    2015-12-01

    This paper introduces a two-step cascade enrichment method for isolating nucleated red blood cells (NRBCs) in maternal blood. The two-step enrichment platform consists of a positive enrichment process based on a red blood cell (RBC) hyperaggregation method and a negative enrichment process using microfluidic technology. An analytical evaluation using blood samples from patients with leukemia showed that the while blood cell (WBC) depletion and NRBC loss rates of the positive enrichment process were 93.98 % and 6.02 %, respectively. Through the two-step cascade enrichment method, 1-396 NRBCs and only 0-6 WBCs were isolated from 1 mL of 18 maternal blood samples. Experimental results also showed that the WBC depletion rate of the proposed two-step method was more than 625,000-fold, and the purity of enriched NRBCs ranged from 20 % to 100 %. Furthermore, SRY (the sex-determining region of the Y chromosome) genes were detected in enriched NRBCs, thereby demonstrating that enriched NRBCs contain fetus-derived NRBCs.

  1. Anemia and red blood cell transfusion in neurocritical care

    PubMed Central

    Kramer, Andreas H; Zygun, David A

    2009-01-01

    Introduction Anemia is one of the most common medical complications to be encountered in critically ill patients. Based on the results of clinical trials, transfusion practices across the world have generally become more restrictive. However, because reduced oxygen delivery contributes to 'secondary' cerebral injury, anemia may not be as well tolerated among neurocritical care patients. Methods The first portion of this paper is a narrative review of the physiologic implications of anemia, hemodilution, and transfusion in the setting of brain-injury and stroke. The second portion is a systematic review to identify studies assessing the association between anemia or the use of red blood cell transfusions and relevant clinical outcomes in various neurocritical care populations. Results There have been no randomized controlled trials that have adequately assessed optimal transfusion thresholds specifically among brain-injured patients. The importance of ischemia and the implications of anemia are not necessarily the same for all neurocritical care conditions. Nevertheless, there exists an extensive body of experimental work, as well as human observational and physiologic studies, which have advanced knowledge in this area and provide some guidance to clinicians. Lower hemoglobin concentrations are consistently associated with worse physiologic parameters and clinical outcomes; however, this relationship may not be altered by more aggressive use of red blood cell transfusions. Conclusions Although hemoglobin concentrations as low as 7 g/dl are well tolerated in most critical care patients, such a severe degree of anemia could be harmful in brain-injured patients. Randomized controlled trials of different transfusion thresholds, specifically in neurocritical care settings, are required. The impact of the duration of blood storage on the neurologic implications of transfusion also requires further investigation. PMID:19519893

  2. [Red Blood Cells Raman Spectroscopy Comparison of Type Two Diabetes Patients and Rats].

    PubMed

    Wang, Lei; Liu, Gui-dong; Mu, Xin; Xiao, Hong-bin; Qi, Chao; Zhang, Si-qi; Niu Wen-ying; Jiang, Guang-kun; Feng, Yue-nan; Bian, Jing-qi

    2015-10-01

    By using confocal Raman spectroscopy, Raman spectra were measured in normal rat red blood cells, normal human red blood cells, STZ induced diabetetic rats red blood cells, Alloxan induced diabetetic rats red blood cells and human type 2 diabetes red blood cells. Then principal component analysis (PCA) with support vector machine (SVM) classifier was used for data analysis, and then the distance between classes was used to judge the degree of close to two kinds of rat model with type 2 diabetes. The results found significant differences in the Raman spectra of red blood cell in diabetic and normal red blood cells. To diabetic red blood cells, the peak in the amide VI C=O deformation vibration band is obvious, and amide V N-H deformation vibration band spectral lines appear deviation. Belong to phospholipid fatty acyl C-C skeleton, the 1 130 cm(-1) spectral line is enhanced and the 1 088 cm(-1) spectral line is abated, which show diabetes red cell membrane permeability increased. Raman spectra of PCA combined with SVM can well separate 5 types of red blood cells. Classifier test results show that the classification accuracy is up to 100%. Through the class distance between the two induced method and human type 2 diabetes, it is found that STZ induced model is more close to human type 2 diabetes. In conclusion, Raman spectroscopy can be used for diagnosis of diabetes and rats STZ induced diabetes method is closer to human type 2 diabetes.

  3. Effect of storage levels of nitric oxide derivatives in blood components

    PubMed Central

    Schechter, Alan N

    2012-01-01

    Background: Potential deleterious effects of red blood cell (RBC) transfusions, especially from blood kept at length, have been ascribed to biochemical changes during storage, including those of nitric oxide (NO) metabolism. Study methods and design: In this study, NO metabolites, nitrite and nitrate, were quantified in RBCs and whole blood with time of storage. Whole blood (WB), leukoreduced (LR), and non-leukoreduced (NLR) components were obtained from healthy volunteer donors and stored in polyvinyl chloride bags for 42 days. Nitrite and nitrate were measured using reductive gas-phase chemiluminescence. Results: Nitrite concentrations initially decreased rapidly from about 150nmol/L, but stabilized at about 44nmol/L in room air for up to 42 days. Nitrate concentrations remained stable during storage at about 35µmol/L. Cells from bags maintained in an argon chamber showed decreased nitrite levels compared to those maintained in room air. Inhibition of enzymes implicated in the NO cycle did not alter nitrite levels. Conclusion: As erythrocytes may contribute to the control of blood flow and oxygen delivery through reduction of nitrite to NO under hypoxic conditions, the present findings provide insight into possible effects of blood transfusion. These measurements may explain some adverse effects of RBC transfusion and suggest ways of optimizing the preservation of stored blood. PMID:24358838

  4. Duration of red blood cell storage and outcomes in pediatric cardiac surgery: an association found for pump prime blood.

    PubMed

    Ranucci, Marco; Carlucci, Concetta; Isgrò, Giuseppe; Boncilli, Alessandra; De Benedetti, Donatella; De la Torre, Teresa; Brozzi, Simonetta; Frigiola, Alessandro

    2009-01-01

    Cardiac surgery using cardiopulmonary bypass in newborns, infants and small children often requires intraoperative red blood cell transfusions to prime the circuit and oxygenator and to replace blood lost during surgery. The purpose of this study was to investigate the influence of red blood cell storage time prior to transfusion on postoperative morbidity in pediatric cardiac operations. One hundred ninety-two consecutive children aged five years or less who underwent cardiac operations using cardiopulmonary bypass and who received red blood cells for priming the cardiopulmonary bypass circuit comprised the blood-prime group. Forty-seven patients receiving red blood cell transfusions after cardiopulmonary bypass were separately analyzed. Patients in the blood-prime group were divided into two groups based on the duration of storage of the red blood cells they received. The newer blood group included patients who received only red blood cells stored for less than or equal to four days and the older blood group included patients who received red blood cells stored for more than four days. Patients in the newer blood group had a significantly lower rate of pulmonary complications (3.5% versus 14.4%; P = 0.011) as well as a lower rate of acute renal failure (0.8% versus 5.2%; P = 0.154) than patients in the older blood group. Major complications (calculated as a composite score based on pulmonary, neurological, and gastroenterological complications, sepsis and acute renal failure) were found in 6.9% of the patients receiving newer blood and 17.1% of the patients receiving older blood (P = 0.027). After adjusting for other possible confounding variables, red blood cell storage time remained an independent predictor of major morbidity. The same association was not found for patients receiving red blood cell transfusions after cardiopulmonary bypass. The storage time of the red blood cells used for priming the cardiopulmonary bypass circuit in cardiac operations on

  5. Storage of red blood cells in a novel polyolefin blood container: a pilot in vitro study.

    PubMed

    Gulliksson, H; Meinke, S; Ravizza, A; Larsson, L; Höglund, P

    2017-01-01

    The present general plasticizer di-2-ethylhexyl-phthalate in polyvinylchloride (PVC) blood bags is only physically dispersed in PVC and will therefore leach into blood components. The objective of this study was to perform a first preliminary red blood cell (RBC) storage evaluation in a new blood bag manufactured of polyolefin without any inclusion of potentially migrating substances. This is a RBC storage study for 42 days. Blood collection was performed in a polyolefin-based PVC-free blood bag. RBCs were prepared within 8 h. Two different RBC additive solutions were used, either PAGGS-M or PAGGG-M. We weekly measured pH, K(+) , glucose, lactate, haemolysis, red cell ATP and 2,3-DPG. RBC storage in PAGGS-M resulted in high haemolysis levels already after 21 days, exceeding the European maximum limit of 0·8%, and low ATP levels by the end of the storage period. With PAGGG-M, haemolysis exceeded 0·8% after 28 days of storage. For additional parameters, the results were comparable to those of previous studies in conventional blood bags. This is a first preliminary study of RBC storage in a new type of blood bags. PAGGG-M gave encouraging results except for its inability to prevent increased haemolysis. There will be room for further development of RBC additive solutions to address the haemolysis problems. Plasma should also be tested regarding the stability of coagulation and activation pathway variables. There may also be a potential for future use of the bag for preparation of pooled buffy-coat-derived platelets. © 2016 International Society of Blood Transfusion.

  6. Remote ischemia preconditioning increases red blood cell deformability through red blood cell-nitric oxide synthase activation.

    PubMed

    Grau, Marijke; Kollikowski, Alexander; Bloch, Wilhelm

    2016-09-12

    Remote ischemia preconditioning (rIPC), short cycles of ischemia (I) and reperfusion (R) of a region remote from the heart, protects against myocardial I/R injury. This effect is triggered by endothelial derived nitric oxide (NO) production. Red blood cells (RBC) are also capable of NO production and it is hypothesized that the beneficial effect of rIPC in terms of cardioprotection is strengthened by increased RBC dependent NO production and improved RBC function after rIPC maneuver. For this purpose, twenty male participants were subjected to four cycles of no-flow ischemia with subsequent reactive hyperemia within the forearm. Blood sampling and measurement of blood pressures and heart rate were carried out pre intervention, after each cycle and 15 min post intervention at both the non-treated and treated arm. These are the first results that show improved RBC deformability in the treated arm after rIPC cycles 1- 4 caused by significantly increased RBC-NO synthase activation. This in turn was associated to increased NO production in both arms after rIPC cycles 3 + 4. Also, systolic and diastolic blood pressures were decreased after rIPC. The findings lead to the conclusion that the cardioprotective effects associated with rIPC include improvement of the RBC-NOS/NO signaling in RBC.

  7. Biochemistry of malaria parasite infected red blood cells by X-ray microscopy.

    PubMed

    Kapishnikov, S; Leiserowitz, L; Yang, Y; Cloetens, P; Pereiro, E; Awamu Ndonglack, F; Matuschewski, K; Als-Nielsen, J

    2017-04-11

    Red blood cells infected by the malaria parasite Plasmodium falciparum are correlatively imaged by tomography using soft X-rays as well as by scanning hard nano-X-ray beam to obtain fluorescence maps of various elements such as S and Fe. In this way one can deduce the amount of Fe bound either in hemoglobin or in hemozoin crystals in the digestive vacuole of the malaria parasite as well as determine the hemoglobin concentrations in the cytosols of the red blood cell and of the parasite. Fluorescence map of K shows that in the parasite's schizont stage the K concentration in the red blood cell cytosol is diminished by a factor of seven relative to a pristine red blood cell but the total amount of K in the infected red blood cell is the same as in the pristine red blood cell.

  8. Effects of pegylated hamster red blood cells on microcirculation.

    PubMed

    Chen, Peter C Y; Huang, Wei; Stassinopoulos, Adonis; Cheung, Anthony T W

    2008-01-01

    The objective of this study was to examine the effects of polyethylene glycol (PEG) treated red blood cells (RBCs) on the microcirculation in a hamster back skin window chamber model. Donor hamster RBCs were PEGylated through an incubation with an activated PEG solution, washed, resuspended, and infused through a 10% volume top loading procedure into the carotid artery in an awake Syrian Golden hamster. Eight hamster groups were treated with activated PEG different sizes and concentrations: 0.05 mM-5 kDa PEG, 0.5 mM-5 kDa PEG, 1.1 mM-5 kDa PEG, 2.2 mM-5 kDa PEG, 22 mM-5 kDa PEG, 0.05 mM-20 kDa PEG, 0.5 mM-20 kDa PEG, and 5 mM-20 kDa PEG. Non-treated RBCs were used as control. The microvascular bed under observation was videotaped 30 min before the infusion and followed for 30 min post infusion. The diameter of individual blood vessels and blood flow velocities in selected vessels was measured. Hematocrit and hemoglobin concentration were recorded before infusion and at the end of experiment. Tissue pO(2) was also monitored. Results showed the hamsters tolerated the PEGylated RBCs without apparent ill effects. No significant changes were recorded for the hematocrit, the hemoglobin concentration, the blood vessel diameters, blood flow velocities, and the interstitial partial oxygen pressure (pO(2)) before, during, and after the injections of PEG-RBCs (P > 0.05). Unlike most hemoglobin-based oxygen carrying compounds, which can cause vasoconstriction, the PEGylated RBCs did not produce any measurable vasoactivity. Together with the absence of rouleaux formation and the fact that PEG molecules can mask the surface antigens on RBCs, PEGylation appeared promising as a circulation enhancement treatment.

  9. Axial dispersion in flowing red blood cell suspensions

    NASA Astrophysics Data System (ADS)

    Podgorski, Thomas; Losserand, Sylvain; Coupier, Gwennou

    2016-11-01

    A key parameter in blood microcirculation is the transit time of red blood cells (RBCs) through an organ, which can influence the efficiency of gas exchange and oxygen availability. A large dispersion of this transit time is observed in vivo and is partly due to the axial dispersion in the flowing suspension. In the classic Taylor-Aris example of a solute flowing in a tube, the combination of molecular diffusion and parabolic velocity profile leads to enhanced axial dispersion. In suspensions of non-Brownian deformable bodies such as RBCs, axial dispersion is governed by a combination of shear induced migration and shear-induced diffusion arising from hydrodynamic interactions. We revisit this problem in the case of RBC pulses flowing in a microchannel and show that the axial dispersion of the pulse eventually saturates with a final extension that depends directly on RBC mechanical properties. The result is especially interesting in the dilute limit since the final pulse length depends only on the channel width, exponent of the migration law and dimensionless migration velocity. In continuous flow, the dispersion of transit times is the result of complex cell-cell and cell-wall interactions and is strongy influenced by the polydispersity of the blood sample. The authors acknowledge support from LabEx TEC21 and CNES.

  10. The buckling instability of aggregating red blood cells.

    PubMed

    Flormann, Daniel; Aouane, Othmane; Kaestner, Lars; Ruloff, Christian; Misbah, Chaouqi; Podgorski, Thomas; Wagner, Christian

    2017-08-11

    Plasma proteins such as fibrinogen induce the aggregation of red blood cells (RBC) into rouleaux, which are responsible for the pronounced shear thinning behavior of blood, control the erythrocyte sedimentation rate (ESR) - a common hematological test - and are involved in many situations of physiological relevance such as structuration of blood in the microcirculation or clot formation in pathological situations. Confocal microscopy is used to characterize the shape of RBCs within rouleaux at equilibrium as a function of macromolecular concentration, revealing the diversity of contact zone morphology. Three different configurations that have only been partly predicted before are identified, namely parachute, male-female and sigmoid shapes, and quantitatively recovered by numerical simulations. A detailed experimental and theoretical analysis of clusters of two cells shows that the deformation increases nonlinearly with the interaction energy. Models indicate a forward bifurcation in which the contacting membrane undergoes a buckling instability from a flat to a deformed contact zone at a critical value of the interaction energy. These results are not only relevant for the understanding of the morphology and stability of RBC aggregates, but also for a whole class of interacting soft deformable objects such as vesicles, capsules or cells in tissues.

  11. Synthetic glycolipid modification of red blood cell membranes.

    PubMed

    Frame, Tom; Carroll, Tim; Korchagina, Elena; Bovin, Nicolai; Henry, Stephen

    2007-05-01

    Glycolipids have a natural ability to insert into red cell (RBC) membranes. Based on this concept the serology of RBCs modified with synthetic analogs of blood group glycolipids (KODE technology) was developed, which entails making synthetic glycolipid constructs engineered to have specific performance criteria. Such synthetic constructs can be made to express a potentially unlimited range of carbohydrate blood group determinants. Synthetic constructs incorporating A, B, acquired-B, and Le(a) blood group determinants were constructed and used to modify RBCs. Modified cells were assessed by routine serologic methods using a range of commercially available monoclonal antibodies. RBCs modified with different concentrations of synthetic glycolipids were able to give controllable serologic results. Synthetic A and B modified cells were able to be created to represent the serology of "weak" subgroups. Specialized cells such as those bearing synthetic acquired-B antigen reacted as expected, but also exhibited extended features due to the cells bearing only specific antigen. Synthetic Le(a)-modified cells reacted as expected with anti-Le(a) reagents, but unexpectedly, were also able to detect the chemical anti-Le(ab) specificity of serologic monoclonal anti-Le(b) reagents. RBCs can be created to express normal and novel carbohydrate profiles by inserting synthetic glycolipids into them. Such cells will be useful in creating specialized antigen panels and for quality control purposes.

  12. Measuring osmosis and hemolysis of red blood cells.

    PubMed

    Goodhead, Lauren K; MacMillan, Frances M

    2017-06-01

    Since the discovery of the composition and structure of the mammalian cell membrane, biologists have had a clearer understanding of how substances enter and exit the cell's interior. The selectively permeable nature of the cell membrane allows the movement of some solutes and prevents the movement of others. This has important consequences for cell volume and the integrity of the cell and, as a result, is of utmost clinical importance, for example in the administration of isotonic intravenous infusions. The concepts of osmolarity and tonicity are often confused by students as impermeant isosmotic solutes such as NaCl are also isotonic; however, isosmotic solutes such as urea are actually hypotonic due to the permeant nature of the membrane. By placing red blood cells in solutions of differing osmolarities and tonicities, this experiment demonstrates the effects of osmosis and the resultant changes in cell volume. Using hemoglobin standard solutions, where known concentrations of hemoglobin are produced, the proportion of hemolysis and the effect of this on resultant hematocrit can be estimated. No change in cell volume occurs in isotonic NaCl, and, by placing blood cells in hypotonic NaCl, incomplete hemolysis occurs. By changing the bathing solution to either distilled water or isosmotic urea, complete hemolysis occurs due to their hypotonic effects. With the use of animal blood in this practical, students gain useful experience in handling tissue fluids and calculating dilutions and can appreciate the science behind clinical scenarios. Copyright © 2017 the American Physiological Society.

  13. Efficacy of fresh packed red blood transfusion in organophosphate poisoning

    PubMed Central

    Bao, Hang-xing; Tong, Pei-jian; Li, Cai-xia; Du, Jing; Chen, Bing-yu; Huang, Zhi-hui; Wang, Ying

    2017-01-01

    Abstract The mortality rate caused by organophosphate (OP) poisoning is still high, even the standard treatment such as atropine and oxime improves a lot. To search for alternative therapies, this study was aimed to investigate the effects of packed red blood cell (RBC) transfusion in acute OP poisoning, and compare the therapeutic effects of RBCs at different storage times. Patients diagnosed with OP poisoning were included in this prospective study. Fresh RBCs (packed RBCs stored less than 10 days) and longer-storage RBCs (stored more than 10 days but less than 35 days) were randomly transfused or not into OP poisoning patients. Cholinesterase (ChE) levels in blood, atropine usage and durations, pralidoxime durations were measured. We found that both fresh and longer-storage RBCs (200–400 mL) significantly increased blood ChE levels 6 hours after transfusion, shortened the duration for ChE recovery and length of hospital stay, and reduced the usage of atropine and pralidoxime. In addition, fresh RBCs demonstrated stronger therapeutic effects than longer-storage RBCs. Packed RBCs might be an alternative approach in patients with OP poisoning, especially during early stages. PMID:28296779

  14. Red Blood Cells Play a Role in Reverse Cholesterol Transport

    PubMed Central

    Hung, Kimberly T.; Berisha, Stela Z.; Ritchey, Brian M.; Santore, Jennifer; Smith, Jonathan D.

    2012-01-01

    Objective Reverse cholesterol transport (RCT) involves the removal of cholesterol from peripheral tissue for excretion in the feces. Here, we determined whether red blood cells (RBCs) can contribute to RCT. Methods and Results We performed a series of studies in apoAI-deficient mice where the HDL-mediated pathway of RCT is greatly diminished. RBCs carried a higher fraction of whole blood cholesterol than plasma in apoAI-deficient mice, and as least as much of the labeled cholesterol derived from injected foam cells appeared in RBCs compared to plasma. To determine if RBCs mediate RCT to the fecal compartment, we measured RCT in anemic and control apoAI-deficient mice and found that anemia decreased RCT to the feces by over 35% after correcting for fecal mass. Transfusion of [3H]cholesterol labeled RBCs led to robust delivery of the labeled cholesterol to the feces in apoAI-deficient hosts. In wild type mice, the majority of the blood cholesterol mass, as well as [3H]cholesterol derived from the injected foam cells, was found in plasma, and anemia did not significantly alter RCT to the feces after correction for fecal mass. Conclusion The RBC cholesterol pool is dynamic and facilitates RCT of peripheral cholesterol to the feces, particularly in the low HDL state. PMID:22499994

  15. Three-dimensional simulation of red blood cells in microcirculation

    NASA Astrophysics Data System (ADS)

    Zhao, Hong; Freund, Jonathan

    2007-11-01

    The hydrodynamic interactions between blood cells are critical for understanding the hemodynamics in microcirculations. We perform a three-dimensional simulation based on the Stokes-flow boundary integral equations to study such systems. The red blood cells are modeled as three-dimensional elastic shells, being highly resistant to any surface dilatation but compliant to bending. The cell shape is approximated by truncated series of spherical harmonics; this spectral representation results in high numerical accuracy and rigorous dealiasing without adding any numerical dissipation. The moving velocities of cell surfaces are solved from a boundary integral equation. The periodic Stokes-flow Green's function is decomposed into a short-range point-to-point-interaction part and a long-range smooth Fourier part; the computational cost is made O(NN) by using a P^3M method. The no-slip boundary condition on the vessel wall is imposed by a penalty method, which enables simulating complex geometries with simple periodic Green's functions. Preliminary results include the deformation of a single cell in a shear flow and multiple cells through a blood vessel.

  16. Analysis of Red Blood Cell Behavior in a Narrow Tube

    NASA Astrophysics Data System (ADS)

    Hosaka, Haruki; Omori, Toshihiro; Imai, Yohsuke; Yamaguchi, Takami; Ishikawa, Takuji

    2012-11-01

    Red Blood Cell (RBC) is a main component of blood accounting for 40 percent in volume, and enclosed by a twodimensional hyper elastic membrane. RBCs strongly influence rheological properties and mass transport of blood. The deformation of RBCs in capillary and at narrowing is also important in considering mechano-transduction of RBCs and hemolysis, though it has not been clarified in detail. Thus, in this study, we investigated the behavior of a RBC flowing in a narrow tube. To carry out the fluid-structure interaction analysis, we coupled a boundary element method to analyze the velocity of the internal and external fluid with a finite element method to analyze the deformation of the membrane. The boundary element method has good calculation accuracy and its computational cost is low because three-dimensional flow filed can be calculated by a two-dimensional computational mesh. The background flow in a tube is pressure-driven Poiseuille flow. Additionally, to reduce the computational time, we implemented massive parallel computation by using GPUs. The results show that the deformation of a RBC is strongly affected by the Capillary number, which is the ratio of viscous force to the elastic force, radius of the tube, and the initial orientation.

  17. Fibrinogen and red blood cells in venous thrombosis.

    PubMed

    Aleman, Maria M; Walton, Bethany L; Byrnes, James R; Wolberg, Alisa S

    2014-05-01

    Deep vein thrombosis and pulmonary embolism, collectively termed venous thromboembolism (VTE), affect over 1 million Americans each year. VTE is triggered by inflammation and blood stasis leading to the formation of thrombi rich in fibrin and red blood cells (RBCs). However, little is known about mechanisms regulating fibrin and RBC incorporation into venous thrombi, or how these components mediate thrombus size or resolution. Both elevated circulating fibrinogen (hyperfibrinogenemia) and abnormal fibrin(ogen) structure and function, including increased fibrin network density and resistance to fibrinolysis, have been observed in plasmas from patients with VTE. Abnormalities in RBC number and/or function have also been associated with VTE risk. RBC contributions to VTE are thought to stem from their effects on blood viscosity and margination of platelets to the vessel wall. More recent studies suggest RBCs also express phosphatidylserine, support thrombin generation, and decrease fibrinolysis. RBC interactions with fibrin(ogen) and cells, including platelets and endothelial cells, may also promote thrombus formation. The contributions of fibrin(ogen) and RBCs to the pathophysiology of VTE warrants further investigation.

  18. Measurement of interaction forces between red blood cells in aggregates by optical tweezers

    SciTech Connect

    Maklygin, A Yu; Priezzhev, A V; Karmenian, A; Nikitin, Sergei Yu; Obolenskii, I S; Lugovtsov, Andrei E; Kisun Li

    2012-06-30

    We have fabricated double-beam optical tweezers and demonstrated the possibility of their use for measuring the interaction forces between red blood cells (erythrocytes). It has been established experimentally that prolonged trapping of red blood cells in a tightly focused laser beam does not cause any visible changes in their shape or size. We have measured the interaction between red blood cells in the aggregate, deformed by optical tweezers.

  19. Duration of red blood cell storage and inflammatory marker generation

    PubMed Central

    Sut, Caroline; Tariket, Sofiane; Chou, Ming Li; Garraud, Olivier; Laradi, Sandrine; Hamzeh-Cognasse, Hind; Seghatchian, Jerard; Burnouf, Thierry; Cognasse, Fabrice

    2017-01-01

    Red blood cell (RBC) transfusion is a life-saving treatment for several pathologies. RBCs for transfusion are stored refrigerated in a preservative solution, which extends their shelf-life for up to 42 days. During storage, the RBCs endure abundant physicochemical changes, named RBC storage lesions, which affect the overall quality standard, the functional integrity and in vivo survival of the transfused RBCs. Some of the changes occurring in the early stages of the storage period (for approximately two weeks) are reversible but become irreversible later on as the storage is extended. In this review, we aim to decipher the duration of RBC storage and inflammatory marker generation. This phenomenon is included as one of the causes of transfusion-related immunomodulation (TRIM), an emerging concept developed to potentially elucidate numerous clinical observations that suggest that RBC transfusion is associated with increased inflammatory events or effects with clinical consequence. PMID:28263172

  20. Geometric localization of thermal fluctuations in red blood cells

    PubMed Central

    Evans, Arthur A.; Bhaduri, Basanta; Popescu, Gabriel; Levine, Alex J.

    2017-01-01

    The thermal fluctuations of membranes and nanoscale shells affect their mechanical characteristics. Whereas these fluctuations are well understood for flat membranes, curved shells show anomalous behavior due to the geometric coupling between in-plane elasticity and out-of-plane bending. Using conventional shallow shell theory in combination with equilibrium statistical physics we theoretically demonstrate that thermalized shells containing regions of negative Gaussian curvature naturally develop anomalously large fluctuations. Moreover, the existence of special curves, “singular lines,” leads to a breakdown of linear membrane theory. As a result, these geometric curves effectively partition the cell into regions whose fluctuations are only weakly coupled. We validate these predictions using high-resolution microscopy of human red blood cells (RBCs) as a case study. Our observations show geometry-dependent localization of thermal fluctuations consistent with our theoretical modeling, demonstrating the efficacy in combining shell theory with equilibrium statistical physics for describing the thermalized morphology of cellular membranes. PMID:28242681

  1. Autoimmune Hemolytic Anemia and Red Blood Cell Autoantibodies.

    PubMed

    Quist, Erin; Koepsell, Scott

    2015-11-01

    Autoimmune hemolytic anemia is a rare disorder caused by autoreactive red blood cell (RBC) antibodies that destroy RBCs. Although autoimmune hemolytic anemia is rare, RBC autoantibodies are encountered frequently and can complicate transfusion workups, impede RBC alloantibody identification, delay distribution of compatible units, have variable clinical significance that ranges from benign to life-threatening, and may signal an underlying disease or disorder. In this review, we discuss the common presenting features of RBC autoantibodies, laboratory findings, ancillary studies that help the pathologist investigate the clinical significance of autoantibodies, and how to provide appropriate patient care and consultation for clinical colleagues. Pathologists must be mindful of, and knowledgeable about, this entity because it not only allows for direct clinical management but also can afford an opportunity to preemptively treat an otherwise silent malignancy or disorder.

  2. Numerical studies of a red blood cell in rectangular microchannels

    NASA Astrophysics Data System (ADS)

    Ye, Ting; Shi, Huixin; Peng, Lina; Li, Yu

    2017-08-01

    The study of red blood cells (RBCs) flowing through rectangular microchannels has attracted an increasing interest, because most of the current microfluidic chips are designed as rectangular microchannels for the purpose of easy fabrication. In this paper, we numerically investigate the 3D motion and deformation of a RBC in rectangular microchannels, by using the smoothed dissipative particle dynamics to model the fluid flow and coupling the immersed boundary method to treat the fluid-RBC interaction. We have considered several fundamental questions concerned in experiments, including the effect of the mechanical properties of RBC, the initial position and orientation of RBC, as well as the asymmetry of the microchannel. In addition, we have demonstrated the differences among the fully 3D, axisymmetric, and 2D simulations of a RBC in microchannels.

  3. Atomic force microscopy: From red blood cells to immunohaematology.

    PubMed

    Yeow, Natasha; Tabor, Rico F; Garnier, Gil

    2017-05-11

    Atomic force microscopy (AFM) offers complementary imaging modes that can provide morphological and structural details of red blood cells (RBCs), and characterize interactions between specific biomolecules and RBC surface antigen. This review describes the applications of AFM in determining RBC health by the observation of cell morphology, elasticity and surface roughness. Measurement of interaction forces between plasma proteins and antibodies against RBC surface antigen using the AFM also brought new information to the immunohaematology field. With constant improvisation of the AFM in resolution and imaging time, the reaction of RBC to changes in the physico-chemistry of its environment and the presence of RBC surface antigen specific-biomolecules is achievable. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Stretching Behavior of Red Blood Cells at High Strain Rates

    NASA Astrophysics Data System (ADS)

    Mancuso, Jordan; Ristenpart, William

    2016-11-01

    Most work on the mechanical behavior of red blood cells (RBCs) has focused on simple shear flows. Relatively little work has examined RBC deformations in the physiologically important extensional flow that occurs at the entrance to a constriction. In particular, previous work suggests that RBCs rapidly stretch out and then retract upon entering the constriction, but to date no model predicts this behavior for the extremely high strain rates typically experienced there. In this work, we use high speed video to perform systematic measurements of the dynamic stretching behavior of RBCs as they enter a microfluidic constriction. We demonstrate that a simple viscoelastic model captures the observed stretching dynamics, up to strain rates as high as 1000 s-1. The results indicate that the effective elastic modulus of the RBC membrane at these strain rates is an order of magnitude larger than moduli measured by micropipette aspiration or other low strain rate techniques.

  5. Red blood cell clustering in Poiseuille microcapillary flow

    NASA Astrophysics Data System (ADS)

    Tomaiuolo, Giovanna; Lanotte, Luca; Ghigliotti, Giovanni; Misbah, Chaouqi; Guido, Stefano

    2012-05-01

    Red blood cells (RBC) flowing in microcapillaries tend to associate into clusters, i.e., small trains of cells separated from each other by a distance comparable to cell size. This process is usually attributed to slower RBCs acting to create a sequence of trailing cells. Here, based on the first systematic investigation of collective RBC flow behavior in microcapillaries in vitro by high-speed video microscopy and numerical simulations, we show that RBC size polydispersity within the physiological range does not affect cluster stability. Lower applied pressure drops and longer residence times favor larger RBC clusters. A limiting cluster length, depending on the number of cells in a cluster, is found by increasing the applied pressure drop. The insight on the mechanism of RBC clustering provided by this work can be applied to further our understanding of RBC aggregability, which is a key parameter implicated in clotting and thrombus formation.

  6. Shape anisotropy induces rotations in optically trapped red blood cells

    NASA Astrophysics Data System (ADS)

    Bambardekar, Kapil; Dharmadhikari, Jayashree A.; Dharmadhikari, Aditya K.; Yamada, Toshihoro; Kato, Tsuyoshi; Kono, Hirohiko; Fujimura, Yuichi; Sharma, Shobhona; Mathur, Deepak

    2010-07-01

    A combined experimental and theoretical study is carried out to probe the rotational behavior of red blood cells (RBCs) in a single beam optical trap. We induce shape changes in RBCs by altering the properties of the suspension medium in which live cells float. We find that certain shape anisotropies result in the rotation of optically trapped cells. Indeed, even normal (healthy) RBCs can be made to rotate using linearly polarized trapping light by altering the osmotic stress the cells are subjected to. Hyperosmotic stress is found to induce shape anisotropies. We also probe the effect of the medium's viscosity on cell rotation. The observed rotations are modeled using a Langevin-type equation of motion that takes into account frictional forces that are generated as RBCs rotate in the medium. We observe good correlation between our measured data and calculated results.

  7. Measurement of red blood cell mechanics during morphological changes.

    PubMed

    Park, YongKeun; Best, Catherine A; Badizadegan, Kamran; Dasari, Ramachandra R; Feld, Michael S; Kuriabova, Tatiana; Henle, Mark L; Levine, Alex J; Popescu, Gabriel

    2010-04-13

    The human red blood cell (RBC) membrane, a fluid lipid bilayer tethered to an elastic 2D spectrin network, provides the principal control of the cell's morphology and mechanics. These properties, in turn, influence the ability of RBCs to transport oxygen in circulation. Current mechanical measurements of RBCs rely on external loads. Here we apply a noncontact optical interferometric technique to quantify the thermal fluctuations of RBC membranes with 3 nm accuracy over a broad range of spatial and temporal frequencies. Combining this technique with a new mathematical model describing RBC membrane undulations, we measure the mechanical changes of RBCs as they undergo a transition from the normal discoid shape to the abnormal echinocyte and spherical shapes. These measurements indicate that, coincident with this morphological transition, there is a significant increase in the membrane's shear, area, and bending moduli. This mechanical transition can alter cell circulation and impede oxygen delivery.

  8. Trapping red blood cells in living animals using optical tweezers.

    PubMed

    Zhong, Min-Cheng; Wei, Xun-Bin; Zhou, Jin-Hua; Wang, Zi-Qiang; Li, Yin-Mei

    2013-01-01

    The recent development of non-invasive imaging techniques has enabled the visualization of molecular events underlying cellular processes in live cells. Although microscopic objects can be readily manipulated at the cellular level, additional physiological insight is likely to be gained by manipulation of cells in vivo, which has not been achieved so far. Here we use infrared optical tweezers to trap and manipulate red blood cells within subdermal capillaries in living mice. We realize a non-contact micro-operation that results in the clearing of a blocked microvessel. Furthermore, we estimate the optical trap stiffness in the capillary. Our work expands the application of optical tweezers to the study of live cell dynamics in animals.

  9. Active elastic network: cytoskeleton of the red blood cell.

    PubMed

    Gov, Nir S

    2007-01-01

    In red blood cells there is a cortical cytoskeleton; a two-dimensional elastic network of membrane-attached proteins. We describe, using a simple model, how the metabolic activity of the cell, through the consumption of ATP, controls the stiffness of this elastic network. The unusual mechanical property of active strain softening is described and compared to experimental data. As a by-product of this activity there is also an active contribution to the amplitude of membrane fluctuations. We model this membrane as a field of independent "curvature motors," and calculate the spectrum of active fluctuations. We find that the active cytoskeleton contributes to the amplitude of the membrane height fluctuations at intermediate wavelengths, as observed experimentally.

  10. Geometric localization of thermal fluctuations in red blood cells.

    PubMed

    Evans, Arthur A; Bhaduri, Basanta; Popescu, Gabriel; Levine, Alex J

    2017-03-14

    The thermal fluctuations of membranes and nanoscale shells affect their mechanical characteristics. Whereas these fluctuations are well understood for flat membranes, curved shells show anomalous behavior due to the geometric coupling between in-plane elasticity and out-of-plane bending. Using conventional shallow shell theory in combination with equilibrium statistical physics we theoretically demonstrate that thermalized shells containing regions of negative Gaussian curvature naturally develop anomalously large fluctuations. Moreover, the existence of special curves, "singular lines," leads to a breakdown of linear membrane theory. As a result, these geometric curves effectively partition the cell into regions whose fluctuations are only weakly coupled. We validate these predictions using high-resolution microscopy of human red blood cells (RBCs) as a case study. Our observations show geometry-dependent localization of thermal fluctuations consistent with our theoretical modeling, demonstrating the efficacy in combining shell theory with equilibrium statistical physics for describing the thermalized morphology of cellular membranes.

  11. Red blood cell dynamics: from cell deformation to ATP release.

    PubMed

    Wan, Jiandi; Forsyth, Alison M; Stone, Howard A

    2011-10-01

    The mechanisms of red blood cell (RBC) deformation under both static and dynamic, i.e., flow, conditions have been studied extensively since the mid 1960s. Deformation-induced biochemical reactions and possible signaling in RBCs, however, were proposed only fifteen years ago. Therefore, the fundamental relationship between RBC deformation and cellular signaling dynamics i.e., mechanotransduction, remains incompletely understood. Quantitative understanding of the mechanotransductive pathways in RBCs requires integrative studies of physical models of RBC deformation and cellular biochemical reactions. In this article we review the physical models of RBC deformation, spanning from continuum membrane mechanics to cellular skeleton dynamics under both static and flow conditions, and elaborate the mechanistic links involved in deformation-induced ATP release.

  12. Anisotropic light scattering of individual sickle red blood cells

    NASA Astrophysics Data System (ADS)

    Kim, Youngchan; Higgins, John M.; Dasari, Ramachandra R.; Suresh, Subra; Park, YongKeun

    2012-04-01

    We present the anisotropic light scattering of individual red blood cells (RBCs) from a patient with sickle cell disease (SCD). To measure light scattering spectra along two independent axes of elongated-shaped sickle RBCs with arbitrary orientation, we introduce the anisotropic Fourier transform light scattering (aFTLS) technique and measured both the static and dynamic anisotropic light scattering. We observed strong anisotropy in light scattering patterns of elongated-shaped sickle RBCs along its major axes using static aFTLS. Dynamic aFTLS analysis reveals the significantly altered biophysical properties in individual sickle RBCs. These results provide evidence that effective viscosity and elasticity of sickle RBCs are significantly different from those of the healthy RBCs.

  13. [Morphometry and electrophoretic mobility of red blood cells from patients with asthma in the intravenous blood laser irradiation].

    PubMed

    Sarycheva, T G; Tsybzhitova, E B; Popova, O V; Aleksandrov, O V

    2009-03-01

    The morphometry and electrophoretic mobility of red blood cells from patients with infection-dependent asthma were comparatively studied prior to and following treatment. The patients who had underwent intravenous laser irradiation of blood (ILIB) in addition to conventional therapy had better morphofunctional parameters of red blood cells, by restoring their normal forms, decreasing their transitional ones, and increasing their electrophoretic mobility to normal values. Those who received traditional drug therapy showed no considerable morphofunctional changes of erythrocytes. Thus, in asthmatic patients, the changes in the morphology and function of red blood cells may suggest their membranous structural changes for whose correction ILIB should used.

  14. Quantitative measurement of red blood cell central pallor and hypochromasia.

    PubMed

    Bacus, J W

    1980-06-01

    A quantitataive definition and techniques of measurement for central pallor of red blood cells are proposed. These are based on high-resolution measurements of absorbance across the center of the cell. Thus, the measurements reflect both variations in cell thickness and hemoglobin concentration. Although contributions of thickness and concentration may differ in individual cells, to a first approximation, a specific cell may be considered as having a similar concentration of hemoglobin throughout, and thus the major contribution to the central pallor is that due to the difference in thickness between the edges of the cell and the center. The definition proposed expresses central pallor as the percentage volume of indentation, comparing the red cell to a disc of uniform absorbance equal to the maximum found at the cell edges. Population distributions of central pallor then provide a basis for quantitation of hypochromasia. The mean and standard deviation of such distributions are proposed as quantitative descriptors. Sample distributions from 27 normal persons, 8 patients with spherocytic anemia and 26 patients with iron deficiency anemia were studied.

  15. Red blood cells ageing markers: a multi-parametric analysis

    PubMed Central

    Bardyn, Manon; Rappaz, Benjamin; Jaferzadeh, Keyvan; Crettaz, David; Tissot, Jean-Daniel; Moon, Inkyu; Turcatti, Gerardo; Lion, Niels; Prudent, Michel

    2017-01-01

    Background Red blood cells collected in citrate-phosphate-dextrose can be stored for up to 42 days at 4 °C in saline-adenine-glucose-mannitol additive solution. During this controlled, but nevertheless artificial, ex vivo ageing, red blood cells accumulate lesions that can be reversible or irreversible upon transfusion. The aim of the present study is to follow several parameters reflecting cell metabolism, antioxidant defences, morphology and membrane dynamics during storage. Materials and methods Five erythrocyte concentrates were followed weekly during 71 days. Extracellular glucose and lactate concentrations, total antioxidant power, as well as reduced and oxidised intracellular glutathione levels were quantified. Microvesiculation, percentage of haemolysis and haematologic parameters were also evaluated. Finally, morphological changes and membrane fluctuations were recorded using label-free digital holographic microscopy. Results The antioxidant power as well as the intracellular glutathione concentration first increased, reaching maximal values after one and two weeks, respectively. Irreversible morphological lesions appeared during week 5, where discocytes began to transform into transient echinocytes and finally spherocytes. At the same time, the microvesiculation and haemolysis started to rise exponentially. After six weeks (expiration date), intracellular glutathione was reduced by 25%, reflecting increasing oxidative stress. The membrane fluctuations showed decreased amplitudes during shape transition from discocytes to spherocytes. Discussion Various types of lesions accumulated at different chemical and cellular levels during storage, which could impact their in vivo recovery after transfusion. A marked effect was observed after four weeks of storage, which corroborates recent clinical data. The prolonged follow-up period allowed the capture of deep storage lesions. Interestingly, and as previously described, the severity of the changes differed among

  16. Red blood cells serve as intravascular carriers of myeloperoxidase.

    PubMed

    Adam, Matti; Gajdova, Silvie; Kolarova, Hana; Kubala, Lukas; Lau, Denise; Geisler, Anne; Ravekes, Thorben; Rudolph, Volker; Tsao, Philip S; Blankenberg, Stefan; Baldus, Stephan; Klinke, Anna

    2014-09-01

    Myeloperoxidase (MPO) is a heme enzyme abundantly expressed in polymorphonuclear neutrophils. MPO is enzymatically capable of catalyzing the generation of reactive oxygen species (ROS) and the consumption of nitric oxide (NO). Thus MPO has both potent microbicidal and, upon binding to the vessel wall, pro-inflammatory properties. Interestingly, MPO - a highly cationic protein - has been shown to bind to both endothelial cells and leukocyte membranes. Given the anionic surface charge of red blood cells, we investigated binding of MPO to erythrocytes. Red blood cells (RBCs) derived from patients with elevated MPO plasma levels showed significantly higher amounts of MPO by flow cytometry and ELISA than healthy controls. Heparin-induced MPO-release from patient-derived RBCs was significantly increased compared to controls. Ex vivo experiments revealed dose and time dependency for MPO-RBC binding, and immunofluorescence staining as well as confocal microscopy localized MPO-RBC interaction to the erythrocyte plasma membrane. NO-consumption by RBC-membrane fragments (erythrocyte "ghosts") increased with incrementally greater concentrations of MPO during incubation, indicating preserved catalytic MPO activity. In vivo infusion of MPO-loaded RBCs into C57BL/6J mice increased local MPO tissue concentrations in liver, spleen, lung, and heart tissue as well as within the cardiac vasculature. Further, NO-dependent relaxation of aortic rings was altered by RBC bound-MPO and systemic vascular resistance significantly increased after infusion of MPO-loaded RBCs into mice. In summary, we find that MPO binds to RBC membranes in vitro and in vivo, is transported by RBCs to remote sites in mice, and affects endothelial function as well as systemic vascular resistance. RBCs may avidly bind circulating MPO, and act as carriers of this leukocyte-derived enzyme. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. Procoagulant activity in stored units of red blood cells.

    PubMed

    Aleshnick, Maya; Foley, Jonathan H; Keating, Friederike K; Butenas, Saulius

    2016-06-10

    The procoagulant activity (PA) of stored units of red blood cells (RBC) increases over time, which is related to the expression/exposure of tissue factor (TF). However, there is a discrepancy between the TF measured and changes in PA observed, suggesting that other blood components contribute to this activity. Our goal was to evaluate changes in PA of stored RBCs and to determine possible contributors to it. RBC units from 4 healthy donors were prepared and stored at 4 °C. On selected days, RBC aliquots were reconstituted with autologous plasma and tested in the thromboelastography assay. Corresponding supernatants were tested in a clotting assay. For all donors, the clotting time (CT) of reconstituted RBC units decreased from ∼3000-4000s on day 1 to ∼1000-1600s on day 30, with the most dramatic changes occurring between days 1 and 5. Anti-TF antibody slightly prolonged the CT. The concentration of TF did not change significantly over time and was within the range of 0.3-2.3 pM. Bovine lactadherin (LTD) prolonged the CT of the RBC (by 2.4-3.4-fold in days 3-5 and by 1.3-1.8-fold at day 30). Anti-TF antibody together with LTD had a cumulative effect on the CT prolongation. CT of supernatants responded to both anti-TF and anti-FXIa antibodies. Three contributors to the PA of stored RBC were identified, i.e. FXIa in solution and phosphatidylserine and TF exposed on blood cells and microparticles. Failure of LTD and antibodies to completely eliminate PA suggests that other components of blood could contribute to it. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. Mortality outcomes in patients transfused with fresher versus older red blood cells: a meta-analysis.

    PubMed

    Chai-Adisaksopha, C; Alexander, P E; Guyatt, G; Crowther, M A; Heddle, N M; Devereaux, P J; Ellis, M; Roxby, D; Sessler, D I; Eikelboom, J W

    2017-04-01

    Among transfused patients, the effect of the duration of red blood cell storage on mortality remains unclear. This study aims to compare the mortality of patients who were transfused with fresher versus older red blood cells. We performed an updated systematic search in the CENTRAL, MEDLINE, EMBASE and CINAHL databases, from January 2015 to October 2016. RCTs of hospitalized patients of any age comparing transfusion of fresher versus older red blood cells were eligible. We used a random-effects model to calculate pooled risk ratios (RRs) with corresponding 95% confidence interval (CI). We identified 14 randomized trials that enrolled 26 374 participants. All-cause mortality occurred in 1219 of 9531 (12·8%) patients who received a transfusion of fresher red blood cells and 1810 of 16 843 (10·7%) in those who received older red blood cells (RR: 1·04, 95% CI: 0·98-1·12, P = 0·90, I(2) = 0%, high certainty for ruling out benefit of fresh blood, moderate certainty for ruling out harm of fresh blood). In six studies, in-hospital death occurred in 691 of 7479 (9·2%) patients receiving fresher red cells and 1291 of 14 757 (8·8%) receiving older red cells (RR: 1·06, 95% CI: 0·97-1·15, P = 0·81, I(2) = 0%, high certainty for ruling out benefit of fresh blood, moderate certainty for ruling out harm of fresh blood). Transfusion of fresher red blood cells does not reduce overall or in-hospital mortality when compared with older red blood cells. Our results support the practice of transfusing patients with the oldest red blood cells available in the blood bank. © 2017 International Society of Blood Transfusion.

  19. Changes of red blood cell surface markers in a blood doping model of neocytolysis.

    PubMed

    Chang, Chung-Che; Chen, Yayan; Modi, Kapil; Awar, Omar; Alfrey, Clarence; Rice, Lawrence

    2009-06-01

    Neocytolysis, the selective hemolysis of young circulating red blood cells (RBCs), contributes to the physiologic control of red cell mass and to pathophysiologic phenomena such as anemia of renal disease, anemia after spaceflight, and blood doping by athletes. Progress in understanding the process is hampered by the lack of established markers to distinguish young from older RBC. Twelve potentially informative RBC surface markers were assayed by flow cytometry in normal blood samples, and 4 were preferentially expressed in young RBC. To create a model of neocytolysis, 3 normal volunteers had recombinant human erythropoietin (rhEpo) administered until mild erythrocytosis occurred, then were studied upon rhEpo withdrawal. Neocytolysis ensued that most evident from a rapid rise in serum ferritin as the iron from young RBC was transferred back to stores. Five additional volunteers had surface markers monitored during and after rhEpo administration. Three subjects with marginal baseline iron stores had blunted response to rhEpo, no significant neocytolysis, and no change in RBC surface marker expression. Two subjects with adequate baseline iron stores developed erythrocytosis followed by neocytolysis. Decreased expression of CD44 (homing-associated cell adhesion molecule) and CD71 (transferrin receptor) seemed to correlate best with neocytolysis; CD35 (complement receptor) less so. Of note, further studies are needed to determine if these changes are causative of red cell destruction. This study begins to establish a human model of neocytolysis, to establish markers differentiating young and old RBC, and to establish a basis for better definition of the process. Although our study is preliminary, the results support the possibility that flow could be useful to detect blood doping because neocytolysis should predictably occur in athletes who surreptitiously blood dope.

  20. Regulation of red blood cell deformability is independent of red blood cell-nitric oxide synthase under hypoxia.

    PubMed

    Grau, Marijke; Lauten, Alexander; Hoeppener, Steffen; Goebel, Bjoern; Brenig, Julian; Jung, Christian; Bloch, Wilhelm; Suhr, Frank

    2016-09-12

    The aim was to study impacts of mild to severe hypoxia on human red blood cell (RBC)-nitric oxide synthase (NOS)-dependent NO production, protein S-nitrosylation and deformability.Ambient air oxygen concentration of 12 healthy subjects was step-wisely reduced from 20.95% to 16.21%, 12.35%, 10% and back to 20.95%. Additional in vitro experiments involved purging of blood (±sodium nitrite) with gas mixtures corresponding to in vivo intervention.Vital and hypoxia-associated parameters showed physiological adaptation to changing demands. Activation of RBC-NOS decreased with increasing hypoxia. RBC deformability, which is influenced by RBC-NOS activation, decreased under mild hypoxia, but surprisingly increased at severe hypoxia in vivo and in vitro. This was causatively induced by nitrite reduction to NO which increased S-nitrosylation of RBC α- and β-spectrins -a critical step to improve RBC deformability. The addition of sodium nitrite prevented decreases of RBC deformability under hypoxia by sustaining S-nitrosylation of spectrins suggesting compensatory mechanisms of non-RBC-NOS-produced NO.The results first time indicate a direct link between maintenance of RBC deformability under severe hypoxia by non-enzymatic NO production because RBC-NOS activation is reduced. These data improve our understanding of physiological mechanisms supporting adequate blood and, thus, oxygen supply to different tissues under severe hypoxia.

  1. [Production of mature red blood cell by using peripheral blood mononuclear cells].

    PubMed

    Jia, Yan-Jun; Liu, Jiang; Zhang, Ke-Ying; Shang, Xiao-Yan; Li, Wei; Wang, Li-Jun; Liu, Na; Wang, Lin; Cui, Shuang; Ni, Lei; Zhao, Bo-Tao; Wang, Dong-Mei; Gao, Song-Ming; Zhang, Zhi-Xin

    2014-10-01

    Most protocols for in vitro producing red blood cells (RBC) use the CD34(+) cells or embryonic stem cells from cord blood, bone marrow or peripheral blood as the start materials. This study was purposed to produce the mature RBC in vitro by using peripheral blood mononuclear cells as start material. The peripheral blood mononuclear cells (PBMNC) were isolated from buffy coat after blood leukapheresis, the mature red blood cells (RBC) were prepared by a 4-step culture protocol. The results showed that after culture by inducing with the different sets of cytokines and supporting by mouse MS-5 cell line, the expansion of PBMNC reached about 1000 folds at the end of the culture. About 90% of cultured RBC were enucleated mature cells which had the comparable morphological characteristics with normal RBC. Colony-forming assays showed that this culture system could stimulate the proliferation of progenitors in PBMNC and differentiate into erythroid cells. The structure and function analysis indicated that the mean cell volume of in vitro cultured RBC was 118 ± 4 fl, which was slight larger than that of normal RBC (80-100 fl); the mean cell hemoglobin was 36 ± 1.2 pg, which was slight higher than that of normal RBC (27-31 pg); the maximal deformation index was 0.46, which approachs level of normal RBC; the glucose-6-phosphate dehydrogenase and pyrurvate kinase levels was consistant with young RBC. It is concluded that PBMNC are feasble, convenient and low-cost source for producing cultured RBC and this culture system is suitable to generate the RBC from PBMNC.

  2. Red blood cell tracking using optical flow methods.

    PubMed

    Guo, Dongmin; van de Ven, Anne L; Zhou, Xiaobo

    2014-05-01

    The investigation of microcirculation is an important task in biomedical and physiological research because the microcirculation information, such as flow velocity and vessel density, is critical to monitor human conditions and develop effective therapies of some diseases. As one of the tasks of the microcirculation study, red blood cell (RBC) tracking presents an effective approach to estimate some parameters in microcirculation. The common method for RBC tracking is based on spatiotemporal image analysis, which requires the image to have high qualification and cells should have fixed velocity. Besides, for in vivo cell tracking, cells may disappear in some frames, image series may have spatial and temporal distortions, and vessel distribution can be complex, which increase the difficulties of RBC tracking. In this paper, we propose an optical flow method to track RBCs. It attempts to describe the local motion for each visible point in the frames using a local displacement vector field. We utilize it to calculate the displacement of a cell in two adjacent frames. Additionally, another optical flow-based method, scale invariant feature transform (SIFT) flow, is also presented. The experimental results show that optical flow is quite robust to the case where the velocity of cell is unstable, while SIFT flow works well when there is a large displacement of the cell between two adjacent frames. Our proposed methods outperform other methods when doing in vivo cell tracking, which can be used to estimate the blood flow directly and help to evaluate other parameters in microcirculation.

  3. Chromium-51 labeling of sheep red blood cells.

    PubMed

    Morrissey, G J; Gravelle, D R; Lo, J; Powe, J E

    1992-02-01

    The failure of sheep red blood cells (RBCs) labeled with Chromium-51 (Cr-51) using the ascorbic acid technique to act as a suitable intravascular marker of blood volume in a septic sheep model prompted us to investigate the technique of radiolabeling sheep erythrocytes with this isotope. Consequently, we studied thirteen sheep in which the labeling efficiency of Cr-51 as sodium chromate and hemoglobin typing was determined for each animal. Mean Cr-51 labeling efficiency of sheep RBCs was 67.5% (n = 13). Although 5 of the 13 sheep were discovered to have two types of hemoglobin (Hb) as determined by electrophoresis, overall labeling efficiency of sheep RBCs was determined to be independent of the type of hemoglobin present. However, when two types of Hb were present (Hb-A and Hb-B), Cr-51 had a higher affinity for Hb-B (80%) than Hb-A (20%) even though both Hb types are present in similar proportions (Hb-A = 53%, Hb-B = 46%). The results of this study indicate that sheep RBCs express a lower labeling efficiency for Cr-51 than do human RBCs and that Cr-51 has a higher affinity for Hb-B than for Hb-A when both hemoglobin types are present. This difference is noteworthy when interpreting Cr-51 RBC data in experimental sheep models. Furthermore, caution should be exercised when extrapolating established human protocols to animal models.

  4. Red blood cell-mimicking synthetic biomaterial particles.

    PubMed

    Doshi, Nishit; Zahr, Alisar S; Bhaskar, Srijanani; Lahann, Joerg; Mitragotri, Samir

    2009-12-22

    Biomaterials form the basis of current and future biomedical technologies. They are routinely used to design therapeutic carriers, such as nanoparticles, for applications in drug delivery. Current strategies for synthesizing drug delivery carriers are based either on discovery of materials or development of fabrication methods. While synthetic carriers have brought upon numerous advances in drug delivery, they fail to match the sophistication exhibited by innate biological entities. In particular, red blood cells (RBCs), the most ubiquitous cell type in the human blood, constitute highly specialized entities with unique shape, size, mechanical flexibility, and material composition, all of which are optimized for extraordinary biological performance. Inspired by this natural example, we synthesized particles that mimic the key structural and functional features of RBCs. Similar to their natural counterparts, RBC-mimicking particles described here possess the ability to carry oxygen and flow through capillaries smaller than their own diameter. Further, they can also encapsulate drugs and imaging agents. These particles provide a paradigm for the design of drug delivery and imaging carriers, because they combine the functionality of natural RBCs with the broad applicability and versatility of synthetic drug delivery particles.

  5. Piezo1 links mechanical forces to red blood cell volume.

    PubMed

    Cahalan, Stuart M; Lukacs, Viktor; Ranade, Sanjeev S; Chien, Shu; Bandell, Michael; Patapoutian, Ardem

    2015-05-22

    Red blood cells (RBCs) experience significant mechanical forces while recirculating, but the consequences of these forces are not fully understood. Recent work has shown that gain-of-function mutations in mechanically activated Piezo1 cation channels are associated with the dehydrating RBC disease xerocytosis, implicating a role of mechanotransduction in RBC volume regulation. However, the mechanisms by which these mutations result in RBC dehydration are unknown. In this study, we show that RBCs exhibit robust calcium entry in response to mechanical stretch and that this entry is dependent on Piezo1 expression. Furthermore, RBCs from blood-cell-specific Piezo1 conditional knockout mice are overhydrated and exhibit increased fragility both in vitro and in vivo. Finally, we show that Yoda1, a chemical activator of Piezo1, causes calcium influx and subsequent dehydration of RBCs via downstream activation of the KCa3.1 Gardos channel, directly implicating Piezo1 signaling in RBC volume control. Therefore, mechanically activated Piezo1 plays an essential role in RBC volume homeostasis.

  6. Regulation of phosphatidylserine exposure in red blood cells.

    PubMed

    Nguyen, Duc Bach; Wagner-Britz, Lisa; Maia, Sara; Steffen, Patrick; Wagner, Christian; Kaestner, Lars; Bernhardt, Ingolf

    2011-01-01

    The exposure of phosphatidylserine (PS) on the outer membrane leaflet of red blood cells (RBCs) serves as a signal for eryptosis, a mechanism for the RBC clearance from blood circulation. The process of PS exposure was investigated as function of the intracellular Ca(2+) content and the activation of PKCα in human and sheep RBCs. Cells were treated with lysophosphatidic acid (LPA), 4-bromo-A23187, or phorbol-12 myristate-13 acetate (PMA) and analysed by flow cytometry, single cell fluorescence video imaging, or confocal microscopy. For human RBCs, no clear correlation existed between the number of cells with an elevated Ca(2+) content and PS exposure. Results are explained by three different mechanisms responsible for the PS exposure in human RBCs: (i) Ca(2+)-stimulated scramblase activation (and flippase inhibition) by LPA, 4-bromo-A23187, and PMA; (ii) PKC activation by LPA and PMA; and (iii) enhanced lipid flop caused by LPA. In sheep RBCs, only the latter mechanism occurs suggesting absence of scramblase activity. Copyright © 2011 S. Karger AG, Basel.

  7. A system for counting fetal and maternal red blood cells.

    PubMed

    Ge, Ji; Gong, Zheng; Chen, Jun; Liu, Jun; Nguyen, John; Yang, Zongyi; Wang, Chen; Sun, Yu

    2014-12-01

    The Kleihauer-Betke (KB) test is the standard method for quantitating fetal-maternal hemorrhage in maternal care. In hospitals, the KB test is performed by a certified technologist to count a minimum of 2000 fetal and maternal red blood cells (RBCs) on a blood smear. Manual counting suffers from inherent inconsistency and unreliability. This paper describes a system for automated counting and distinguishing fetal and maternal RBCs on clinical KB slides. A custom-adapted hardware platform is used for KB slide scanning and image capturing. Spatial-color pixel classification with spectral clustering is proposed to separate overlapping cells. Optimal clustering number and total cell number are obtained through maximizing cluster validity index. To accurately identify fetal RBCs from maternal RBCs, multiple features including cell size, roundness, gradient, and saturation difference between cell and whole slide are used in supervised learning to generate feature vectors, to tackle cell color, shape, and contrast variations across clinical KB slides. The results show that the automated system is capable of completing the counting of over 60,000 cells (versus ∼2000 by technologists) within 5 min (versus ∼15 min by technologists). The throughput is improved by approximately 90 times compared to manual reading by technologists. The counting results are highly accurate and correlate strongly with those from benchmarking flow cytometry measurement.

  8. A strategy to reduce inappropriate red blood cell transfusion.

    PubMed

    Brandis, K; Richards, B; Ghent, A; Weinstein, S

    1994-06-06

    To evaluate the effectiveness of policies intended to decrease unnecessary packed red cell transfusions. The transfusion records of a 550-bed acute care facility were obtained and two six-month periods, one before and one after the introduction of new transfusion policies, were compared. Meaningful reductions were seen in crossmatch requests, number of units crossmatched and units transfused. After standardising for rising patient numbers, units transfused per 1000 admissions fell by 28.8%. Units crossmatched fell by slightly more than did units transfused, resulting in lower crossmatch-to-transfusion ratios, and indicating more effective use of resources. Total requests fell while "group-and-screen" requests rose, showing a shift toward more appropriate ordering in the face of increasing workload. The transfusion policies have succeeded in curtailing unnecessary transfusion practices. They included the lowering of "transfusion-triggering" haemoglobin levels, registrar or consultant approval of transfusions and enforcement of patient consent and chart documentation of transfusion indications, verified by the laboratory. The surgical blood ordering schedule was reviewed under the overall direction of the transfusion committee. A strong institutional commitment is required to lift the profile of blood transfusion.

  9. Introduction to porcine red blood cells: implications for xenotransfusion.

    PubMed

    Zhu, A

    2000-04-01

    Advances in the field of xenotransplantation raise the intriguing possibility of using porcine red blood cells (pRBCs) as an alternative source for blood transfusion. The domestic pig is considered the most likely donor species for xenotransplantation. However, identification of xenoantigens on porcine erythrocytes and elucidation of their possible roles in antibody-mediated RBC destruction are necessary for developing clinical strategies to circumvent immunological incompatibility between humans and pigs. Although the alphaGal epitope (Galalpha1,3Galbeta1,4GIcNAc-R) is the major xenoantigen on porcine erythrocytes and is responsible for the binding of the majority of human natural antibodies, other non-alphaGal xenoantigens have been identified. The importance of these non-alphaGal xenoantigens in binding human natural antibodies and subsequently triggering immunological responses cannot be underestimated. Our data suggest that non-alphaGal xenoantigen(s) identified on the porcine erythrocyte membrane are not only recognized by xenoreactive human natural antibodies but are also involved in complement-mediated hemolysis.

  10. Red blood cell as an adaptive optofluidic microlens.

    PubMed

    Miccio, L; Memmolo, P; Merola, F; Netti, P A; Ferraro, P

    2015-03-11

    The perspective of using live cells as lenses could open new revolutionary and intriguing scenarios in the future of biophotonics and biomedical sciences for endoscopic vision, local laser treatments via optical fibres and diagnostics. Here we show that a suspended red blood cell (RBC) behaves as an adaptive liquid-lens at microscale, thus demonstrating its imaging capability and tunable focal length. In fact, thanks to the intrinsic elastic properties, the RBC can swell up from disk volume of 90 fl up to a sphere reaching 150 fl, varying focal length from negative to positive values. These live optofluidic lenses can be fully controlled by triggering the liquid buffer's chemistry. Real-time accurate measurement of tunable focus capability of RBCs is reported through dynamic wavefront characterization, showing agreement with numerical modelling. Moreover, in analogy to adaptive optics testing, blood diagnosis is demonstrated by screening abnormal cells through focal-spot analysis applied to an RBC ensemble as a microlens array.

  11. Neonatal nucleated red blood cells in G6PD deficiency.

    PubMed

    Yeruchimovich, Mark; Shapira, Boris; Mimouni, Francis B; Dollberg, Shaul

    2002-05-01

    The objective of this study is to study the absolute number of nucleated red blood cells (RBC) at birth, an index of active fetal erythropoiesis, in infants with G6PD deficiency and in controls. We tested the hypothesis that hematocrit and hemoglobin would be lower, and absolute nucleated RBC counts higher, in the G6PD deficient and that these changes would be more prominent in infants exposed passively to fava bean through maternal diet. Thirty-two term infants with G6PD deficiency were compared with 30 term controls. Complete blood counts with manual differential counts were obtained within 12 hours of life. Absolute nucleated RBC and corrected leukocyte counts were computed from the Coulter results and the differential count. G6PD deficient patients did not differ from controls in terms of gestational age, birth weight, or Apgar scores or in any of the hematologic parameters studied, whether or not the mother reported fava beans consumption in the days prior to delivery. Although intrauterine hemolysis is possible in G6PD deficient fetuses exposed passively to fava beans, our study supports that such events must be very rare.

  12. Vitamin E nanoemulsion activity on stored red blood cells.

    PubMed

    Silva, C A L; Azevedo Filho, C A; Pereira, G; Silva, D C N; Castro, M C A B; Almeida, A F; Lucena, S C A; Santos, B S; Barjas-Castro, M L; Fontes, A

    2017-06-01

    Stored red blood cells (RBCs) undergo numerous changes that have been termed RBC storage lesion, which can be related to oxidative damage. Vitamin E is an important antioxidant, acting on cell lipids. Thus, this study aimed to investigate vitamin E activity on stored RBCs. We prepared a vitamin E nanoemulsion that was added to RBC units and stored at 4 °C. Controls, without vitamin E, were kept under the same conditions. Reactive oxygen species (ROS) production was monitored for up to 35 days of storage. RBC elasticity was also evaluated using an optical tweezer system. Vitamin E-treated samples presented a significant decrease in ROS production. Additionally, the elastic constant for vitamin E-treated RBCs did not differ from the control. Vitamin E decreased the amount of ROS in stored RBCs. Because vitamin E acts on lipid oxidation, results suggest that protein oxidation should also be considered a key factor for erythrocyte elastic properties. Thus, further studies combining vitamin E with protein antioxidants deserve attention, aiming to better preserve overall stored RBC properties. © 2017 British Blood Transfusion Society.

  13. Perioperative Red Blood Cell Transfusion: What We Do Not Know

    PubMed Central

    Lei, Chong; Xiong, Li-Ze

    2015-01-01

    Objective: Blood transfusion saves lives but may also increase the risk of injury. The objective of this review was to evaluate the possible adverse effects related to transfusion of red blood cell (RBC) concentrates stored for prolonged periods. Data Sources: The data used in this review were mainly from PubMed articles published in English up to February 2015. Study Selection: Clinical and basic research articles were selected according to their relevance to this topic. Results: The ex vivo changes to RBC that occur during storage are collectively called storage lesion. It is still inconclusive if transfusion of RBC with storage lesion has clinical relevance. Multiple ongoing prospective randomized controlled trials are aimed to clarify this clinical issue. It was observed that the adverse events related to stored RBC transfusion were prominent in certain patient populations, including trauma, critical care, pediatric, and cardiac surgery patients, which leads to the investigation of underlying mechanisms. It is demonstrated that free hemoglobin toxicity, decreasing of nitric oxide bioavailability, and free iron-induced increasing of inflammation may play an important role in this process. Conclusion: It is still unclear whether transfusion of older RBC has adverse effects, and if so, which factors determine such clinical effects. However, considering the magnitude of transfusion and the widespread medical significance, potential preventive strategies should be considered, especially for the susceptible recipients. PMID:26315088

  14. Red blood cell as an adaptive optofluidic microlens

    NASA Astrophysics Data System (ADS)

    Miccio, L.; Memmolo, P.; Merola, F.; Netti, P. A.; Ferraro, P.

    2015-03-01

    The perspective of using live cells as lenses could open new revolutionary and intriguing scenarios in the future of biophotonics and biomedical sciences for endoscopic vision, local laser treatments via optical fibres and diagnostics. Here we show that a suspended red blood cell (RBC) behaves as an adaptive liquid-lens at microscale, thus demonstrating its imaging capability and tunable focal length. In fact, thanks to the intrinsic elastic properties, the RBC can swell up from disk volume of 90 fl up to a sphere reaching 150 fl, varying focal length from negative to positive values. These live optofluidic lenses can be fully controlled by triggering the liquid buffer’s chemistry. Real-time accurate measurement of tunable focus capability of RBCs is reported through dynamic wavefront characterization, showing agreement with numerical modelling. Moreover, in analogy to adaptive optics testing, blood diagnosis is demonstrated by screening abnormal cells through focal-spot analysis applied to an RBC ensemble as a microlens array.

  15. Manipulation of red blood cells with electric field

    NASA Astrophysics Data System (ADS)

    Saboonchi, Hossain; Esmaeeli, Asghar

    2009-11-01

    Manipulation of bioparticles and macromolecules is the central task in many biological and biotechnological processes. The current methods for physical manipulation takes advantage of different forces such as acoustic, centrifugal, magnetic, electromagnetic, and electric forces, as well as using optical tweezers or filtration. Among all these methods, however, the electrical forces are particularly attractive because of their favorable scale up with the system size which makes them well-suited for miniaturization. Currently the electric field is used for transportation, poration, fusion, rotation, and separation of biological cells. The aim of the current research is to gain fundamental understanding of the effect of electric field on the human red blood cells (RBCs) using direct numerical simulation. A front tracking/finite difference technique is used to solve the fluid flow and electric field equations, where the fluid in the cell and the blood (plasma) is modeled as Newtonian and incompressible, and the interface separating the two is treated as an elastic membrane. The behavior of RBCs is investigated as a function of the controlling parameters of the problem such as the strength of the electric field.

  16. Calcium in Red Blood Cells—A Perilous Balance

    PubMed Central

    Bogdanova, Anna; Makhro, Asya; Wang, Jue; Lipp, Peter; Kaestner, Lars

    2013-01-01

    Ca2+ is a universal signalling molecule involved in regulating cell cycle and fate, metabolism and structural integrity, motility and volume. Like other cells, red blood cells (RBCs) rely on Ca2+ dependent signalling during differentiation from precursor cells. Intracellular Ca2+ levels in the circulating human RBCs take part not only in controlling biophysical properties such as membrane composition, volume and rheological properties, but also physiological parameters such as metabolic activity, redox state and cell clearance. Extremely low basal permeability of the human RBC membrane to Ca2+ and a powerful Ca2+ pump maintains intracellular free Ca2+ levels between 30 and 60 nM, whereas blood plasma Ca2+ is approximately 1.8 mM. Thus, activation of Ca2+ uptake has an impressive impact on multiple processes in the cells rendering Ca2+ a master regulator in RBCs. Malfunction of Ca2+ transporters in human RBCs leads to excessive accumulation of Ca2+ within the cells. This is associated with a number of pathological states including sickle cell disease, thalassemia, phosphofructokinase deficiency and other forms of hereditary anaemia. Continuous progress in unravelling the molecular nature of Ca2+ transport pathways allows harnessing Ca2+ uptake, avoiding premature RBC clearance and thrombotic complications. This review summarizes our current knowledge of Ca2+ signalling in RBCs emphasizing the importance of this inorganic cation in RBC function and survival. PMID:23698771

  17. Piezo1 links mechanical forces to red blood cell volume

    PubMed Central

    Cahalan, Stuart M; Lukacs, Viktor; Ranade, Sanjeev S; Chien, Shu; Bandell, Michael; Patapoutian, Ardem

    2015-01-01

    Red blood cells (RBCs) experience significant mechanical forces while recirculating, but the consequences of these forces are not fully understood. Recent work has shown that gain-of-function mutations in mechanically activated Piezo1 cation channels are associated with the dehydrating RBC disease xerocytosis, implicating a role of mechanotransduction in RBC volume regulation. However, the mechanisms by which these mutations result in RBC dehydration are unknown. In this study, we show that RBCs exhibit robust calcium entry in response to mechanical stretch and that this entry is dependent on Piezo1 expression. Furthermore, RBCs from blood-cell-specific Piezo1 conditional knockout mice are overhydrated and exhibit increased fragility both in vitro and in vivo. Finally, we show that Yoda1, a chemical activator of Piezo1, causes calcium influx and subsequent dehydration of RBCs via downstream activation of the KCa3.1 Gardos channel, directly implicating Piezo1 signaling in RBC volume control. Therefore, mechanically activated Piezo1 plays an essential role in RBC volume homeostasis. DOI: http://dx.doi.org/10.7554/eLife.07370.001 PMID:26001274

  18. Skeleton deformation of red blood cells during tank treading motions

    NASA Astrophysics Data System (ADS)

    Zhu, Qiang; Peng, Zhangli

    2012-11-01

    By coupling a fluid-structure interaction algorithm with a three-level multiscale structural model, we simulate the tank treading responses of erythrocytes (red blood cells, or RBC) in shear flows. The fluid motion is depicted within the Stokes-flow framework, and is mathematically formulated with the boundary integral equations. The structural model takes into account the flexible connectivity between the lipid bilayer and the protein skeleton as well as the viscoelastic responses. The concentration of this study is on the transient process involving the development of the local area deformation of the protein skeleton. Under the assumption that the protein skeleton is stress-free in the natural biconcave configuration, our simulations indicate the following properties: (1) During tank treading motions it takes long time for significant area deformations to establish. For cells with diminished connectivity between the lipid bilayer and the protein skeleton (e.g. cells with mutations or defects), the relaxation time will be greatly reduced; (2) Deformations of the skeleton depend on the initial orientation of the cell with respect to the incoming flow; (3) The maximum area expansion occurs around the regions corresponding to the dimples in the original biconcave state; (4) Oscillations in cell geometry (breathing) and orientation (e.g. swinging) are observed. This work was supported by the National Heart, Lung, and Blood Institute under award number R01HL092793.

  19. Viable Bacteria Associated with Red Blood Cells and Plasma in Freshly Drawn Blood Donations

    PubMed Central

    Damgaard, Christian; Magnussen, Karin; Enevold, Christian; Nilsson, Martin; Tolker-Nielsen, Tim; Holmstrup, Palle; Nielsen, Claus Henrik

    2015-01-01

    Objectives Infection remains a leading cause of post-transfusion mortality and morbidity. Bacterial contamination is, however, detected in less than 0.1% of blood units tested. The aim of the study was to identify viable bacteria in standard blood-pack units, with particular focus on bacteria from the oral cavity, and to determine the distribution of bacteria revealed in plasma and in the red blood cell (RBC)-fraction. Design Cross-sectional study. Blood were separated into plasma and RBC-suspensions, which were incubated anaerobically or aerobically for 7 days on trypticase soy blood agar (TSA) or blue lactose plates. For identification colony PCR was performed using primers targeting 16S rDNA. Setting Blood donors attending Capital Region Blood Bank, Copenhagen University Hospital, Rigshospitalet, Hvidovre, Denmark, October 29th to December 10th 2013. Participants 60 donors (≥50 years old), self-reported medically healthy. Results Bacterial growth was observed on plates inoculated with plasma or RBCs from 62% of the blood donations. Growth was evident in 21 (35%) of 60 RBC-fractions and in 32 (53%) of 60 plasma-fractions versus 8 of 60 negative controls (p = 0.005 and p = 2.6x10-6, respectively). Propionibacterium acnes was found in 23% of the donations, and Staphylococcus epidermidis in 38%. The majority of bacteria identified in the present study were either facultative anaerobic (59.5%) or anaerobic (27.8%) species, which are not likely to be detected during current routine screening. Conclusions Viable bacteria are present in blood from donors self-reported as medically healthy, indicating that conventional test systems employed by blood banks insufficiently detect bacteria in plasma. Further investigation is needed to determine whether routine testing for anaerobic bacteria and testing of RBC-fractions for adherent bacteria should be recommended. PMID:25751254

  20. Modeling the potential impact on the US blood supply of transfusing critically ill patients with fresher stored red blood cells.

    PubMed

    Simonetti, Arianna; Ezzeldin, Hussein; Menis, Mikhail; McKean, Stephen; Izurieta, Hector; Anderson, Steven A; Forshee, Richard A

    2017-01-01

    Although some studies have suggested that transfusion recipients may have better medical outcomes if transfused with red blood cell units stored for a short time, the overall body of evidence shows mixed results. It is important to understand how using fresher stored red blood cell units for certain patient groups may affect blood availability. Based on the Stock-and-Flow simulation model of the US blood supply developed by Simonetti et al. 2014, we evaluated a newly implemented allocation method of preferentially transfusing fresher stored red blood cell units to a subset of high-risk group of critically ill patients and its potential impact on supply. Simulation results showed that, depending on the scenario, the US blood total supply might be reduced between 2-42%, when compared to the standard of care in transfusion medicine practice. Among our simulated scenarios, we observed that the number of expired red blood cell units modulated the supply levels. The age threshold of the required red blood cell units was inversely correlated with both the supply levels and the number of transfused units that failed to meet that age threshold. To our knowledge, this study represents the first attempt to develop a comprehensive framework to evaluate the impact of preferentially transfusing fresher stored red blood cells to the higher-risk critically ill patients on supply. Model results show the difficulties to identify an optimal scenario.

  1. Modeling the potential impact on the US blood supply of transfusing critically ill patients with fresher stored red blood cells

    PubMed Central

    Ezzeldin, Hussein; Menis, Mikhail; McKean, Stephen; Izurieta, Hector; Anderson, Steven A.; Forshee, Richard A.

    2017-01-01

    Background Although some studies have suggested that transfusion recipients may have better medical outcomes if transfused with red blood cell units stored for a short time, the overall body of evidence shows mixed results. It is important to understand how using fresher stored red blood cell units for certain patient groups may affect blood availability. Methods Based on the Stock-and-Flow simulation model of the US blood supply developed by Simonetti et al. 2014, we evaluated a newly implemented allocation method of preferentially transfusing fresher stored red blood cell units to a subset of high-risk group of critically ill patients and its potential impact on supply. Results Simulation results showed that, depending on the scenario, the US blood total supply might be reduced between 2-42%, when compared to the standard of care in transfusion medicine practice. Among our simulated scenarios, we observed that the number of expired red blood cell units modulated the supply levels. The age threshold of the required red blood cell units was inversely correlated with both the supply levels and the number of transfused units that failed to meet that age threshold. Conclusion To our knowledge, this study represents the first attempt to develop a comprehensive framework to evaluate the impact of preferentially transfusing fresher stored red blood cells to the higher-risk critically ill patients on supply. Model results show the difficulties to identify an optimal scenario. PMID:28319164

  2. Cryopreserved packed red blood cells in surgical patients: past, present, and future.

    PubMed

    Chang, Alex; Kim, Young; Hoehn, Richard; Jernigan, Peter; Pritts, Timothy

    2016-09-08

    Since the advent of anticoagulation and component storage of human blood products, allogeneic red blood cell transfusion has been one of the most common practices in modern medicine. Efforts to reduce the biochemical effects of storage, collectively known as the red blood cell storage lesion, and prolong the storage duration have led to numerous advancements in erythrocyte storage solutions. Cryopreservation and frozen storage of red blood cells in glycerol have been successfully utilised by many civilian and military institutions worldwide. Through progressive improvements in liquid storage of erythrocytes in novel storage solutions, the logistical need for cryopreserved red blood cells in the civilian setting has diminished. A growing body of current literature is focused on the clinical consequences of packed red blood cell age. Modern cryopreservation techniques show promise as a cost-effective method to ameliorate the negative effect of the red blood cell storage lesion, while meeting the technical and logistical needs of both civilian and military medicine. This review outlines the history of red blood cell cryopreservation, the clinical impact of red cell storage, and highlights the current literature on frozen blood and its impact on modern transfusion.

  3. Raman spectroscopy of stored red blood cells: evaluating clinically-relevant biochemical markers in donated blood

    NASA Astrophysics Data System (ADS)

    Atkins, Chad G.; Buckley, Kevin; Chen, Deborah; Schulze, H. G.; Devine, Dana V.; Blades, Michael W.; Turner, Robin F. B.

    2015-07-01

    Modern transfusion medicine relies on the safe, secure, and cost-effective delivery of donated red blood cells (RBCs). Once isolated, RBCs are suspended in a defined additive solution and stored in plastic blood bags in which, over time, they undergo chemical, physiological, and morphological changes that may have a deleterious impact on some patients. Regulations limit the storage period to 42 days and the cells do not routinely undergo analytical testing before use. In this study, we use Raman spectroscopy to interrogate stored RBCs and we identify metabolic and cell-breakdown products, such as haemoglobin and membrane fragments, that build-up in the blood bags as the cells age. Our work points the way to the development of an instrument which could quickly and easily assess the biochemical nature of stored RBC units before they are transfused.

  4. Trends in US minority red blood cell unit donations.

    PubMed

    Yazer, Mark H; Delaney, Meghan; Germain, Marc; Karafin, Matthew S; Sayers, Merlyn; Vassallo, Ralph; Ziman, Alyssa; Shaz, Beth

    2017-05-01

    To provide the appropriately diverse blood supply necessary to support alloimmunized and chronically transfused patients, minority donation recruitment programs have been implemented. This study investigated temporal changes in minority red blood cell (RBC) donation patterns in the United States. Data on donor race and ethnicity from 2006 through 2015, including the number of unique donors, collections, RBCs successfully donated, and average annual number of RBC donations per donor (donor fraction), were collected from eight US blood collectors. Minority donors were stratified into the following groups: Asian, black or African American, Hispanic or Latino, Native Indian or Alaska Native, Native Hawaiian or other Pacific Islander, white, multiracial/other, and no answer/not sure. Over the 10-year period, white donors annually constituted the majority of unique donors (range, 70.7%-73.9%), had the greatest proportion of collections (range, 76.1%-79.8%), and donated the greatest proportion of RBC units (range, 76.3%-80.2%). These donors also had the highest annual donor fraction (range, 1.82-1.91 units per donor). Black or African American donors annually constituted between 4.9 and 5.2% of all donors during the study period and donated between 4.0 and 4.3% of all RBC units. Linear regression analysis revealed decreasing numbers of donors, collections, and donated RBC units from white donors over time. Although the US population has diversified, and minority recruitment programs have been implemented, white donors constitute the majority of RBC donors and donations. Focused and effective efforts are needed to increase the proportion of minority donors. © 2017 AABB.

  5. Mechanical properties of stored red blood cells using optical tweezers

    NASA Astrophysics Data System (ADS)

    Fontes, Adriana; Alexandre de Thomaz, Andre; de Ysasa Pozzo, Liliana; de Lourdes Barjas-Castro, Maria; Brandao, Marcelo M.; Saad, Sara T. O.; Barbosa, Luiz Carlos; Cesar, Carlos Lenz

    2005-08-01

    We have developed a method for measuring the red blood cell (RBC) membrane overall elasticity μ by measuring the deformation of the cells when dragged at a constant velocity through a plasma fluid by an optical tweezers. The deformability of erythrocytes is a critical determinant of blood flow in the microcirculation. We tested our method and hydrodynamic models, which included the presence of two walls, by measuring the RBC deformation as a function of drag velocity and of the distance to the walls. The capability and sensitivity of this method can be evaluated by its application to a variety of studies, such as, the measurement of RBC elasticity of sickle cell anemia patients comparing homozygous (HbSS), including patients taking hydroxyrea (HU) and heterozygous (HbAS) with normal donors and the RBC elasticity measurement of gamma irradiated stored blood for transfusion to immunosupressed patients as a function of time and dose. These studies show that the technique has the sensitivity to discriminate heterozygous and homozygous sickle cell anemia patients from normal donors and even follow the course of HU treatment of Homozygous patients. The gamma irradiation studies show that there is no significant change in RBC elasticity over time for up to 14 days of storage, regardless of whether the unit was irradiated or not, but there was a huge change in the measured elasticity for the RBC units stored for more than 21 days after irradiation. These finds are important for the assessment of stored irradiated RBC viability for transfusion purposes because the present protocol consider 28 storage days after irradiation as the limit for the RBC usage.

  6. Rat red blood cell storage lesions in various additive solutions.

    PubMed

    Jani, Vivek P; Yalcin, Ozlem; Williams, Alexander T; Popovsky, Mark A; Cabrales, Pedro

    2017-06-03

    Small rodent models are routinely used to evaluate the safety and efficacy of blood transfusions. Limited comprehensive literature exists about effect of different storage solutions in rat red blood cells (RBCs) characteristics. RBCs undergo time dependent biochemical and biophysical changes during storage known as hypothermic storage lesions (HSLs). This study evaluates the effects of RBC additive solutions (AS) during storage of rat RBCs. Blood was leukoreduced and stored as per manufacturer instructions at 4°C up to 42-days. Three solutions, CPDA-1; AS-1; and AS-7 (SOLX), were evaluated. Biochemical parameters measured included extracellular K +, pH, hemolysis, 2,3-diphosphoglycerate (2,3-DPG), oxygen affinity, ATP, and lactate. Mechanical properties measured included RBC deformability, elongation index (EI), RBC membrane shear elastic modulus (SEM), mean corpuscular volume (MCV), viscosity, and aggregability. There were no differences in biochemical or mechanical parameters at baseline or after one week of storage. However, after two weeks, AS-7 preserved biochemical and mechanical properties as compared to CPDA-1 and AS-1. Changes were observed to be significant after 14-days of storage. AS-7 prevented extracellular K + increase, reduced acidosis, showed lower hemolysis, preserved ATP and 2,3-DPG levels (consequently oxygen affinity), and reduced lactate. AS-7, when compared to CPDA-1 and AS-1, prevented the reduction in RBC deformability and was found to preserve the EI at multiple shear stresses, the membrane SEM, the aggregability and viscosity. Rat RBCs stored with AS-7 presented reduced changes in biochemical and mechanical parameters, when compared with rat RBCs stored in CPDA-1 and AS-1, after as early as two weeks of storage.

  7. Mechanisms of red blood cells agglutination in antibody-treated paper.

    PubMed

    Jarujamrus, Purim; Tian, Junfei; Li, Xu; Siripinyanond, Atitaya; Shiowatana, Juwadee; Shen, Wei

    2012-05-07

    Recent reports on using bio-active paper and bio-active thread to determine human blood type have shown a tremendous potential of using these low-cost materials to build bio-sensors for blood diagnosis. In this work we focus on understanding the mechanisms of red blood cell agglutination in the antibody-loaded paper. We semi-quantitatively evaluate the percentage of antibody molecules that are adsorbed on cellulose fibres and can potentially immobilize red blood cells on the fibre surface, and the percentage of the molecules that can desorb from the cellulose fibre surface into the blood sample and cause haemagglutination reaction in the bulk of a blood sample. Our results show that 34 to 42% of antibody molecules in the papers treated with commercial blood grouping antibodies can desorb from the fibre surface. When specific antibody molecules are released into the blood sample via desorption, haemagglutination reaction occurs in the blood sample. The reaction bridges the red cells in the blood sample bulk to the layer of red cells immobilized on the fibre surface by the adsorbed antibody molecules. The desorbed antibody also causes agglutinated lumps of red blood cells to form. These lumps cannot pass through the pores of the filter paper. The immobilization and filtration of agglutinated red cells give reproducible identification of positive haemagglutination reaction. Results from this study provide information for designing new bio-active paper-based devices for human blood typing with improved sensitivity and specificity.

  8. Nanoparticle encapsulation in red blood cells enables blood-pool magnetic particle imaging hours after injection

    NASA Astrophysics Data System (ADS)

    Rahmer, J.; Antonelli, A.; Sfara, C.; Tiemann, B.; Gleich, B.; Magnani, M.; Weizenecker, J.; Borgert, J.

    2013-06-01

    Magnetic particle imaging (MPI) is a new medical imaging approach that is based on the nonlinear magnetization response of super-paramagnetic iron oxide nanoparticles (SPIOs) injected into the blood stream. To date, real-time MPI of the bolus passage of an approved MRI SPIO contrast agent injected into the tail vein of living mice has been demonstrated. However, nanoparticles are rapidly removed from the blood stream by the mononuclear phagocyte system. Therefore, imaging applications for long-term monitoring require the repeated administration of bolus injections, which complicates quantitative comparisons due to the temporal variations in concentration. Encapsulation of SPIOs into red blood cells (RBCs) has been suggested to increase the blood circulation time of nanoparticles. This work presents first evidence that SPIO-loaded RBCs can be imaged in the blood pool of mice several hours after injection using MPI. This finding is supported by magnetic particle spectroscopy performed to quantify the iron concentration in blood samples extracted from the mice 3 and 24 h after injection of SPIO-loaded RBCs. Based on these results, new MPI applications can be envisioned, such as permanent 3D real-time visualization of the vessel tree during interventional procedures, bleeding monitoring after stroke, or long-term monitoring and treatment control of cardiovascular diseases.

  9. Effect of red blood cell aggregation and sedimentation on optical coherence tomography signals from blood samples

    NASA Astrophysics Data System (ADS)

    Kirillin, M. Yu; Priezzhev, A. V.; Tuchin, V. V.; Wang, R. K.; Myllylä, R.

    2005-08-01

    In this work, Monte Carlo simulation is used to obtain model optical coherence tomography (OCT) signals from a horizontally orientated blood layer at different stages of red blood cell (RBC) aggregation and sedimentation processes. The parameters for aggregating and sedimenting blood cells were chosen based on the data available from the literature and our earlier experimental studies. We consider two different cases: a suspension of washed RBCs in physiological solution (where aggregation does not take place) and RBCs in blood plasma (which provides necessary conditions for aggregation). Good agreement of the simulation results with the available experimental data shows that the chosen optical parameters are reasonable. The dependence of the numbers of photons contributing to the OCT signal on the number of experienced scattering events was analysed for each simulated signal. It was shown that the maxima of these dependences correspond to the peaks in the OCT signals related to the interfaces between the layers of blood plasma and blood cells. Their positions can be calculated from the optical thicknesses of the layers, and the absorption and scattering coefficients of the media.

  10. Isolation of fetal nucleated red blood cells from maternal blood in normal and aneuploid pregnancies.

    PubMed

    Prieto, Belén; Cándenas, Mercedes; Venta, Rafael; Ladenson, Jack H; Alvarez, Francisco V

    2002-07-01

    Fetal nucleated red blood cells (NRBC) have been widely reported in maternal blood during pregnancy. However, there is no consensus with regard to their presence in all pregnancies. Therefore, the usefulness of developing a fetal NRBC-based noninvasive method suitable for clinical prenatal diagnosis remains uncertain. Fluorescence in situ hybridization (FISH) method was used to evaluate the ability of one of our own monoclonal antibodies (mAb), 2B7.4, to isolate fetal NRBC from maternal blood by magnetic activated cell sorting (MACS). Our mAb was able to isolate from 25 to 822 NRBC from all of the 45 maternal blood samples included in this study. A correct diagnosis was achieved in 21 out of 24 pregnancies carrying trisomic fetuses (87.5%), with a fetal/maternal NRBC frequency of 8.4%. In contrast, a significantly lower percentage of fetal NRBC (0.2%) was observed in 22% of pregnancies carrying a chromosomally normal male fetus, that were correctly predicted. In conclusion, using 2B7.4 mAb we succeeded in isolating NRBC from the maternal blood samples, but most of the isolated cells were maternal in origin. Nevertheless, a higher number of fetal NRBC was found in the peripheral blood of pregnant women carrying aneuploid fetuses, which could allow development of a screening method for prenatal diagnosis of fetal aneuploidies.

  11. Bio-inspired Cryo-ink Preserves Red Blood Cell Phenotype and Function during Nanoliter Vitrification

    PubMed Central

    Assal, Rami El; Guven, Sinan; Gurkan, Umut Atakan; Gozen, Irep; Shafiee, Hadi; Dalbeyber, Sedef; Abdalla, Noor; Thomas, Gawain; Fuld, Wendy; Illigens, Ben M.W.; Estanislau, Jessica; Khoory, Joseph; Kaufman, Richard; Zylberberg, Claudia; Lindeman, Neal; Wen, Qi; Ghiran, Ionita; Demirci, Utkan

    2014-01-01

    Current red blood cell cryopreservation methods utilize bulk volumes, causing cryo-injury of cells, which results in irreversible disruption of cell morphology, mechanics, and function. An innovative approach to preserve human red blood cell morphology, mechanics, and function following vitrification in nanoliter volumes is developed using a novel cryo-ink integrated with a bio-printing approach. PMID:25047246

  12. Nucleated red blood cell count in term and preterm newborns: reference values at birth.

    PubMed

    Perrone, S; Vezzosi, P; Longini, M; Marzocchi, B; Tanganelli, D; Testa, M; Santilli, T; Buonocore, G

    2005-03-01

    The prognostic value of nucleated red blood cell count at birth in relation to neonatal outcome has been established. However, reference values were needed to usefully interpret this variable. The normal range of reference values for absolute nucleated red blood cell count in 695 preterm and term newborns is reported.

  13. Healthy and unhealthy red blood cell detection in human blood smears using neural networks.

    PubMed

    Elsalamony, Hany A

    2016-04-01

    One of the most common diseases that affect human red blood cells (RBCs) is anaemia. To diagnose anaemia, the following methods are typically employed: an identification process that is based on measuring the level of haemoglobin and the classification of RBCs based on a microscopic examination in blood smears. This paper presents a proposed algorithm for detecting and counting three types of anaemia-infected red blood cells in a microscopic coloured image using circular Hough transform and morphological tools. Anaemia cells include sickle, elliptocytosis, microsite cells and cells with unknown shapes. Additionally, the resulting data from the detection process have been analysed by a prevalent data analysis technique: the neural network. The experimental results for this model have demonstrated high accuracy for analysing healthy/unhealthy cells. This algorithm has achieved a maximum detection of approximately 97.8% of all cells in 21 microscopic images. Effectiveness rates of 100%, 98%, 100%, and 99.3% have been achieved using neural networks for sickle cells, elliptocytosis cells, microsite cells and cells with unknown shapes, respectively. Copyright © 2016. Published by Elsevier Ltd.

  14. P2X and P2Y receptor signaling in red blood cells.

    PubMed

    Sluyter, Ronald

    2015-01-01

    Purinergic signaling involves the activation of cell surface P1 and P2 receptors by extracellular nucleosides and nucleotides such as adenosine and adenosine triphosphate (ATP), respectively. P2 receptors comprise P2X and P2Y receptors, and have well-established roles in leukocyte and platelet biology. Emerging evidence indicates important roles for these receptors in red blood cells. P2 receptor activation stimulates a number of signaling pathways in progenitor red blood cells resulting in microparticle release, reactive oxygen species formation, and apoptosis. Likewise, activation of P2 receptors in mature red blood cells stimulates signaling pathways mediating volume regulation, eicosanoid release, phosphatidylserine exposure, hemolysis, impaired ATP release, and susceptibility or resistance to infection. This review summarizes the distribution of P2 receptors in red blood cells, and outlines the functions of P2 receptor signaling in these cells and its implications in red blood cell biology.

  15. Effect of warming and flow rate conditions of blood warmers on red blood cell integrity.

    PubMed

    Poder, T G; Pruneau, D; Dorval, J; Thibault, L; Fisette, J-F; Bédard, S K; Jacques, A; Beauregard, P

    2016-11-01

    Fluid warmers are routinely used to reduce the risk of hypothermia and cardiac complications associated with the infusion of cold blood products. However, warming blood products could generate haemolysis. This study was undertaken to compare the impact of temperature of blood warmers on the per cent haemolysis of packed red blood cells (RBCs) heated at different flow rates as well as non-flow conditions. Infusion warmers used were calibrated at 41·5°C ± 0·5°C and 37·5°C ± 0·5°C. Cold RBC units stored at 4°C in AS-3 (n = 30), aged 30-39 days old, were divided into half units before being allocated under two different scenarios (i.e. infusion pump or syringe). Blood warmers were effective to warm cold RBCs to 37·5°C or 41·5°C when used in conjunction with an infusion pump at flow rate up to 600 ml/h. However, when the warmed blood was held in a syringe for various periods of time, such as may occur in neonatal transfusions, the final temperature was below the expected requirements with measurement as low as 33·1°C. Increasing the flow with an infusion pump increased haemolysis in RBCs from 0·2% to up to 2·1% at a flow rate of 600 ml/h regardless of the warming device used (P < 0·05). No relevant increase of haemolysis was observed using a syringe. The use of a blood warmer adjusted to 41·5°C is probably the best choice for reducing the risk of hypothermia for the patient without generating haemolysis. However, we should be cautious with the use of an infusion pump for RBC transfusion, particularly at high flow rates. © 2016 International Society of Blood Transfusion.

  16. Photoacoustic measurements of red blood cell oxygen saturation in blood bags in situ

    NASA Astrophysics Data System (ADS)

    Pinto, Ruben N.; Bagga, Karan; Douplik, Alexandre; Acker, Jason P.; Kolios, Michael C.

    2017-03-01

    Red blood cell (RBC) transfusion is a critical component of the health care services. RBCs are stored in blood bags in hypothermic temperatures for a maximum of 6 weeks post donation. During this in vitro storage period, RBCs have been documented to undergo changes in structure and function due to mechanical and biochemical stress. Currently, there are no assessment methods that monitor the quality of RBCs within blood bags stored for transfusion. Conventional assessment methods require the extraction of samples, consequently voiding the sterility of the blood bags and potentially rendering them unfit for transfusions. It is hypothesized that photoacoustic (PA) technology can provide a rapid and non-invasive indication of RBC quality. In this study, a novel PA setup was developed for the acquisition of oxygen saturation (SO2) of two blood bags in situ. These measurements were taken throughout the lifespan of the blood bags (42 days) and compared against the clinical gold standard method of the blood gas analyzer (BGA). SO2 values of the blood bags increased monotonically throughout the storage period. A strong correlation between PA SO2 and BGA SO2 was found, however, PA values were on average 3.5% lower. Both techniques found the bags to increase by an SO2 of approximately 20%, and measured very similar rates of SO2 change. Future work will be focused on determining the cause of discrepancy between SO2 values acquired from PA versus BGA, as well as establishing links between the measured SO2 increase and other changes in RBC in situ.

  17. Blood volume and red cell life span (M113), part C

    NASA Technical Reports Server (NTRS)

    Johnson, P. C., Jr.

    1973-01-01

    Prechamber, in-chamber, and postchamber blood samples taken from Skylab simulation crewmembers did not indicate significant shortening of the red cell life span during the mission. This does not suggest that the space simulation environment could not be associated with red cell enzyme changes. It does show that any changes in enzymes were not sufficiently great to significantly shorten red cell survival. There was no evidence of bone marrow erythropoetic suppression nor was there any evidence of increased red cell destruction.

  18. Blood volume and red cell life span (M113), part C

    NASA Technical Reports Server (NTRS)

    Johnson, P. C., Jr.

    1973-01-01

    Prechamber, in-chamber, and postchamber blood samples taken from Skylab simulation crewmembers did not indicate significant shortening of the red cell life span during the mission. This does not suggest that the space simulation environment could not be associated with red cell enzyme changes. It does show that any changes in enzymes were not sufficiently great to significantly shorten red cell survival. There was no evidence of bone marrow erythropoetic suppression nor was there any evidence of increased red cell destruction.

  19. Novel, high-yield red blood cell production methods from CD34-positive cells derived from human embryonic stem, yolk sac, fetal liver, cord blood, and peripheral blood.

    PubMed

    Olivier, Emmanuel; Qiu, Caihong; Bouhassira, Eric E

    2012-08-01

    The current supply of red blood cells expressing rare blood groups is not sufficient to cover all the existing transfusion needs for chronically transfused patients, such as sickle cell disease homozygous carriers, because of alloimmunization. In vitro production of cultured red blood cells is slowly emerging as a possible complement to the existing collection-based red blood cell procurement system. The yield of cultured red blood cells can theoretically be maximized by amplifying the stem, progenitor, or precursor compartment. Here, we combined methods designed to expand these three compartments to optimize the yield of cultured red blood cells and found that exposing CD34(+) cells to a short pulse of cytokines favorable for erythroid differentiation prior to stem cell expansion followed by progenitor expansion produced the highest yield of erythroid cells. This novel serum-free red blood cell production protocol was efficient on CD34(+) cells derived from human embryonic stem cells, 6-8-week yolk sacs, 16-18-week fetal livers, cord blood, and peripheral blood. The yields of cells obtained with these new protocols were larger by an order of magnitude than the yields observed previously. Globin expression analysis by high-performance liquid chromatography revealed that these expansion protocols generally yielded red blood cells that expressed a globin profile similar to that expected for the developmental age of the CD34(+) cells.

  20. Novel, High-Yield Red Blood Cell Production Methods from CD34-Positive Cells Derived from Human Embryonic Stem, Yolk Sac, Fetal Liver, Cord Blood, and Peripheral Blood

    PubMed Central

    Olivier, Emmanuel; Qiu, Caihong

    2012-01-01

    The current supply of red blood cells expressing rare blood groups is not sufficient to cover all the existing transfusion needs for chronically transfused patients, such as sickle cell disease homozygous carriers, because of alloimmunization. In vitro production of cultured red blood cells is slowly emerging as a possible complement to the existing collection-based red blood cell procurement system. The yield of cultured red blood cells can theoretically be maximized by amplifying the stem, progenitor, or precursor compartment. Here, we combined methods designed to expand these three compartments to optimize the yield of cultured red blood cells and found that exposing CD34+ cells to a short pulse of cytokines favorable for erythroid differentiation prior to stem cell expansion followed by progenitor expansion produced the highest yield of erythroid cells. This novel serum-free red blood cell production protocol was efficient on CD34+ cells derived from human embryonic stem cells, 6–8-week yolk sacs, 16–18-week fetal livers, cord blood, and peripheral blood. The yields of cells obtained with these new protocols were larger by an order of magnitude than the yields observed previously. Globin expression analysis by high-performance liquid chromatography revealed that these expansion protocols generally yielded red blood cells that expressed a globin profile similar to that expected for the developmental age of the CD34+ cells. PMID:23197866

  1. Vesiculation of healthy and defective red blood cells

    NASA Astrophysics Data System (ADS)

    Li, He; Lykotrafitis, George

    2015-07-01

    Vesiculation of mature red blood cells (RBCs) contributes to removal of defective patches of the erythrocyte membrane. In blood disorders, which are related to defects in proteins of the RBC membrane, vesiculation of the plasma membrane is intensified. Several hypotheses have been proposed to explain RBC vesiculation but the exact underlying mechanisms and what determines the sizes of the vesicles are still not completely understood. In this work, we apply a two-component coarse-grained molecular dynamics RBC membrane model to study how RBC vesiculation is controlled by the membrane spontaneous curvature and by lateral compression of the membrane. Our simulation results show that the formation of small homogeneous vesicles with a diameter less than 40 nm can be attributed to a large spontaneous curvature of membrane domains. On the other hand, compression on the membrane can cause the formation of vesicles with heterogeneous composition and with sizes comparable with the size of the cytoskeleton corral. When spontaneous curvature and lateral compression are simultaneously considered, the compression on the membrane tends to facilitate formation of vesicles originating from curved membrane domains. We also simulate vesiculation of RBCs with membrane defects connected to hereditary elliptocytosis (HE) and to hereditary spherocytosis (HS). When the vertical connectivity between the lipid bilayer and the membrane skeleton is elevated, as in normal RBCs, multiple vesicles are shed from the compressed membrane with diameters similar to the cytoskeleton corral size. In HS RBCs, where the connectivity between the lipid bilayer and the cytoskeleton is reduced, larger-size vesicles are released under the same compression ratio as in normal RBCs. Lastly, we find that vesicles released from HE RBCs can contain cytoskeletal filaments due to fragmentation of the membrane skeleton while vesicles released from the HS RBCs are depleted of cytoskeletal filaments.

  2. Colloidal Properties of Nanoerythrosomes Derived from Bovine Red Blood Cells.

    PubMed

    Kuo, Yuan-Chia; Wu, Hsuan-Chen; Hoang, Dao; Bentley, William E; D'Souza, Warren D; Raghavan, Srinivasa R

    2016-01-12

    Liposomes are nanoscale containers that are typically synthesized from lipids using a high-shear process such as extrusion or sonication. While liposomes are extensively used in drug delivery, they do suffer from certain problems including limited colloidal stability and short circulation times in the body. As an alternative to liposomes, we explore a class of container structures derived from erythrocytes (red blood cells). The procedure involves emptying the inner contents of these cells (specifically hemoglobin) and resuspending the empty structures in buffer, followed by sonication. The resulting structures are termed nanoerythrosomes (NERs), i.e., they are membrane-covered nanoscale containers, much like liposomes. Cryo-transmission electron microscopy (cryo-TEM) and small-angle neutron scattering (SANS) are employed for the first time to study these NERs. The results reveal that the NERs are discrete spheres (∼110 nm diameter) with a unilamellar membrane of thickness ∼4.5 nm. Remarkably, the biconcave disc-like shape of erythrocytes is also exhibited by the NERs under hypertonic conditions. Moreover, unlike typical liposomes, NERs show excellent colloidal stability in both buffer as well as in serum at room temperature, and are also able to withstand freeze-thaw cycling. We have explored the potential for using NERs as colloidal vehicles for targeted delivery. Much like conventional liposomes, NER membranes can be decorated with fluorescent or other markers, solutes can be encapsulated in the cores of the NERs, and NERs can be targeted to specifically bind to mammalian cells. Our study shows that NERs are a promising and versatile class of nanostructures. NERs that are harvested from a patient's own blood and reconfigured for nanomedicine can potentially offer several benefits including biocompatibility, minimization of immune response, and extended circulation time in the body.

  3. Understanding thread properties for red blood cell antigen assays: weak ABO blood typing.

    PubMed

    Nilghaz, Azadeh; Zhang, Liyuan; Li, Miaosi; Ballerini, David R; Shen, Wei

    2014-12-24

    "Thread-based microfluidics" research has so far focused on utilizing and manipulating the wicking properties of threads to form controllable microfluidic channels. In this study we aim to understand the separation properties of threads, which are important to their microfluidic detection applications for blood analysis. Confocal microscopy was utilized to investigate the effect of the microscale surface morphologies of fibers on the thread's separation efficiency of red blood cells. We demonstrated the remarkably different separation properties of threads made using silk and cotton fibers. Thread separation properties dominate the clarity of blood typing assays of the ABO groups and some of their weak subgroups (Ax and A3). The microfluidic thread-based analytical devices (μTADs) designed in this work were used to accurately type different blood samples, including 89 normal ABO and 6 weak A subgroups. By selecting thread with the right surface morphology, we were able to build μTADs capable of providing rapid and accurate typing of the weak blood groups with high clarity.

  4. Red blood cells radial dispersion in blood flowing through microchannels: The role of temperature.

    PubMed

    Pinho, Diana; Rodrigues, Raquel O; Faustino, Vera; Yaginuma, Tomoko; Exposto, José; Lima, Rui

    2016-07-26

    The behavior of suspensions of individual blood cells, such as red blood cells (RBCs), flowing through microvessels and microfluidic systems depend strongly on the hematocrit (Hct), microvessel topology and cell properties. Although it is well known that blood rheological properties are temperature dependent, to the best of our knowledge no work has studied the role of the temperature on the RBCs dispersion. A powerful way to investigate this latter effect is through a high-speed video microscopy system, which provides detailed flow measurements of each individual RBC. Hence, the effect of temperature on the RBCs dispersion flowing through a 100μm glass capillary was examined by means of a confocal micro-PTV system. Hundreds of labeled RBCs were tracked at moderate Hct (12%) and at four different temperatures, i.e., 25°C, 32°C, 37°C and 42°C. The results yielded an enhancement of the RBCs diffusion as the temperature increases. Hence, our findings show that RBCs radial dispersion is temperature dependent and as a result the temperature should not be ignored in future blood flow studies. We believe that this finding is important for a better understanding of blood mass transport mechanisms under both physiological and pathological conditions. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Polyphenols enhance total oxidant-scavenging capacities of human blood by binding to red blood cells.

    PubMed

    Koren, Erez; Kohen, Ron; Ginsburg, Isaac

    2010-06-01

    The present study offers a new look at the role of erythrocytes and of erythrocytes-polyphenol complexes as potent 'sinks' for reactive oxygen species. We hereby show that human erythrocytes have the capacity not only to carry oxygen, but also to bind avidly to their surfaces a large variety of polyphenol antioxidants, which endows upon such complexes enhanced total oxidant-scavenging capacities (TOSC). This was proven by using confocal microscopy, 2,2-diphenyl-1-picrylhydrazyl radical, Folin-Ciocalteu's reagent, cyclic voltammetry and chemiluminescence techniques. The results presented suggest that the true TOSC of blood is the sum of intracellular antioxidants of red blood cells and other blood cells (mainly due to catalase), the polyphenols bound to their surfaces and the antioxidant agents present in plasma. Since erythrocytes can avidly bind and rapidly remove circulating polyphenols, the rule of the thumb to quantify antioxidants in health and disease processes exclusively in plasma as customary in clinical settings, does not represent the true TOSC of whole blood. We also postulate that circulating erythrocytes and possibly also other blood cells might be constantly coated by polyphenols from supplemented nutrients, which act as antioxidant depots and can thus act as protectors against the harmful consequences of oxidative stress. Further studies are needed to determine the faith of polyphenols in the circulation and their sequestration in the spleen.

  6. Abnormal red blood cells detection using adaptive neuro-fuzzy system.

    PubMed

    Babazadeh Khameneh, Nahid; Arabalibeik, Hossein; Salehian, Piruz; Setayeshi, Saeed

    2012-01-01

    Features like size, shape, and volume of red blood cells are important factors in diagnosing related blood disorders such as iron deficiency and anemia. This paper proposes a method to detect abnormality in red blood cells using cell microscopic images. Adaptive local thresholding and bounding box methods are used to extract inner and outer diameters of red cells. An adaptive network-based fuzzy inference system (ANFIS) is used to classify blood samples to normal and abnormal. Accuracy of the proposed method and area under ROC curve are 96.6% and 0.9950 respectively.

  7. Chronic red blood cell exchange to prevent clinical complications in sickle cell disease.

    PubMed

    Cabibbo, Sergio; Fidone, Carmelo; Garozzo, Giovanni; Antolino, Agostino; Manenti, Giovanna Oriella; Bennardello, Francesco; Licitra, Vincenzo; Calabrese, Salvatore; Costantino, Francesco; Travali, Simone; Distefano, Roberto; Bonomo, Pietro

    2005-06-01

    We tracked the results of 394 manual or automatic red blood cell exchanges done with a cell separator in 20 sickle cell patients at high risk for recurrent complications. Over an average of 6 years, none of the patients developed complications related to the procedure or to the increased blood use. It was safe and effective in preventing complications of sickle cell disease, and if done automatically, reduced iron overload. Ferritin levels also decreased in patients treated with automatic red blood cell exchange. Furthermore, using Single Donor Red Blood Cell units (SDRC) we reduced the potential exposure to transfusion transmitted infectious diseases (TTI).

  8. A smart core-sheath nanofiber that captures and releases red blood cells from the blood

    NASA Astrophysics Data System (ADS)

    Shi, Q.; Hou, J.; Zhao, C.; Xin, Z.; Jin, J.; Li, C.; Wong, S.-C.; Yin, J.

    2016-01-01

    A smart core-sheath nanofiber for non-adherent cell capture and release is demonstrated. The nanofibers are fabricated by single-spinneret electrospinning of poly(N-isopropylacrylamide) (PNIPAAm), polycaprolactone (PCL) and nattokinase (NK) solution blends. The self-assembly of PNIPAAm and PCL blends during the electrospinning generates the core-sheath PCL/PNIPAAm nanofibers with PNIPAAm as the sheath. The PNIPAAm-based core-sheath nanofibers are switchable between hydrophobicity and hydrophilicity with temperature change and enhance stability in the blood. When the nanofibers come in contact with blood, the NK is released from the nanofibers to resist platelet adhesion on the nanofiber surface, facilitating the direct capture and isolation of red blood cells (RBCs) from the blood above phase-transition temperature of PNIPAAm. Meanwhile, the captured RBCs are readily released from the nanofibers with temperature stimuli in an undamaged manner. The release efficiency of up to 100% is obtained while maintaining cellular integrity and function. This work presents promising nanofibers to effectively capture non-adherent cells and release for subsequent molecular analysis and diagnosis of single cells.A smart core-sheath nanofiber for non-adherent cell capture and release is demonstrated. The nanofibers are fabricated by single-spinneret electrospinning of poly(N-isopropylacrylamide) (PNIPAAm), polycaprolactone (PCL) and nattokinase (NK) solution blends. The self-assembly of PNIPAAm and PCL blends during the electrospinning generates the core-sheath PCL/PNIPAAm nanofibers with PNIPAAm as the sheath. The PNIPAAm-based core-sheath nanofibers are switchable between hydrophobicity and hydrophilicity with temperature change and enhance stability in the blood. When the nanofibers come in contact with blood, the NK is released from the nanofibers to resist platelet adhesion on the nanofiber surface, facilitating the direct capture and isolation of red blood cells (RBCs) from

  9. [Establishment of Method for Detecting Red Blood Cell Osmotic Fragility by Flow Cytometry].

    PubMed

    Zhu, Hong-Yan; Meng, Qiang; Ouyan, Hong-Mei; Dong, Ting; Zhang, Qiong-Yue; Zhou, You-Quan; Ping, Zhu-Xian

    2016-02-01

    To establish a new method for detection of red blood cell osmotic fragility by using flow cytometry. The hypotension salt solution of different concentrations (0.70 ml normal saline+0.3 ml deionized water, 0.60 ml normal saline+0.40 ml deionized water and 0.55 ml normal saline+0.45 ml deionized water) were prepared with normal saline and deionized water, in which the red blood cells were suspended, and the residual red blood cells were detected by flow cytometer. There was no significant difference in percentage of residual red blood cells between different time points detected by flow cytometer in 3 different hypotonic salt solutions. The percentage of residual red blood cells in B+C+D+E+F+G detected time region was different among 3 NaCl dilution groups. The percentage of residual red blood cells in normal control was lower than that in hemoglobinopathy group. The percentage of residual red blood cells in hereditary spherocytosis (HS) group was obviously lower than that in hemoglobinopathy and normal control groups. The comparison of 3 different dilution concentrations found that the second concentration (0.60 ml normal saline+0.40 ml deionized water) is more suitable to screen HS by FC500 flow cytometer. The detection of red cell osmotic fragility by using flow cytometry is a simple, rapid, objective and economic way that can be an effective screening method for diagnose the HS.

  10. A particle dynamic model of red blood cell aggregation kinetics.

    PubMed

    Fenech, Marianne; Garcia, Damien; Meiselman, Herbert J; Cloutier, Guy

    2009-11-01

    To elucidate the relationship between microscopic red blood cell (RBC) interactions and macroscopic rheological behavior, we propose a two-dimensional particle model capable of mimicking the main characteristics of RBC aggregation kinetics. The mechanical model of RBCs sheared in Couette flow is based on Newton law. We assumed a hydrodynamic force to move particles, a force to describe aggregation and an elasticity force. The role of molecular mass and concentration of neutral polymers on aggregation [Neu, B., and H. J. Meiselman. Biophys. J. 83:2482-2490, 2002] could be mimicked. Specifically, it was shown that for any shear rate (SR), the mean aggregate size (MAS) grew with time until it reached a constant value, which is consistent with in vitro experiments. It was also demonstrated that we could mimic the modal relationship between MAS and SR and the occurrence of maximum aggregation at about 0.1 s(-1). As anticipated, simulations indicated that an increase in aggregation force augmented MAS. Further, augmentation of the depletion layer thickness influenced MAS only for SR close to zero, which is a new finding. To conclude, our contribution reveals that the aggregation force intensity and SR influence the steady state MAS, and that the depletion and layer thickness affect the aggregation speed.

  11. Premature red blood cells have decreased aggregation and enhanced aggregability.

    PubMed

    Arbell, D; Orkin, B; Bar-Oz, B; Barshtein, G; Yedgar, S

    2008-06-01

    Preterm infants are highly susceptible to ischemic damage. This damage is most obvious in the brain, retina, and gastrointestinal tract. Studies focusing on the rheological properties of premature red blood cells (pRBCs) have consistently shown minimal or no RBC aggregation. Previously, measurements of pRBC aggregation kinetics indicated that specific plasma properties are responsible for the decreased RBC aggregation observed in the neonates, but that their specific RBC properties do not affect it. However, the strength of interaction in the pRBC aggregates as a function of medium composition has not been tested. In our previous research, we described clinically relevant parameters, that is, the aggregate resistance to disaggregation by flow. With the help of a cell flow property analyzer (CFA), we can monitor RBC aggregation by direct visualization of its dynamics during flow. We used the CFA to examine pRBC (from 9 premature babies) in the natural plasma and in PBS buffer supplemented with dextran (500 kDa) to distinguish between RBC intrinsic-cellular and plasma factors. pRBCs suspended in the native plasma showed minimal or no aggregation in comparison to normal adult RBC. When we transferred pRBCs from the same sample to the dextran solution, enhanced resistance to disaggregation by flow was apparent.

  12. Aggregation of red blood cells in patients with Gaucher disease.

    PubMed

    Adar, Tomer; Ben-Ami, Ronen; Elstein, Deborah; Zimran, Ari; Berliner, Shlomo; Yedgar, Saul; Barshtein, Gershon

    2006-08-01

    Gaucher disease is associated with increased red blood cell (RBC) aggregation, but the pathophysiological significance of this phenomenon and its correlation with disease manifestations are unclear. RBC aggregation was evaluated in 43 patients with Gaucher disease and 53 healthy controls. Dynamic RBC aggregation was examined in a narrow-gap flow chamber at varying shear stress. Compared with the controls, RBC aggregation in Gaucher disease was increased by 25%. Comparison of RBC aggregation in autologous plasma and in dextran (500 kDa) showed an increase both in plasma-dependent (extrinsic) and -independent (intrinsic) RBC aggregation. Subgroup analysis revealed that increased RBC aggregation was limited to patients with an intact spleen. RBC aggregation in patients did not correlate with plasma fibrinogen concentration, disease severity, enzyme replacement therapy or genotype. We conclude that RBC aggregation is increased in patients with Gaucher disease and an intact spleen, possibly reflecting the accumulation of glucocerebroside and other substances in the plasma and RBC membranes of these patients. Our results do not support a role for RBC aggregation in the pathogenesis of vascular complications of Gaucher disease.

  13. 3D morphometry of red blood cells by digital holography.

    PubMed

    Memmolo, Pasquale; Miccio, Lisa; Merola, Francesco; Gennari, Oriella; Netti, Paolo Antonio; Ferraro, Pietro

    2014-12-01

    Three dimensional (3D) morphometric analysis of flowing and not-adherent cells is an important aspect for diagnostic purposes. However, diagnostics tools need to be quantitative, label-free and, as much as possible, accurate. Recently, a simple holographic approach, based on shape from silhouette algorithm, has been demonstrated for accurate calculation of cells biovolume and displaying their 3D shapes. Such approach has been adopted in combination with holographic optical tweezers and successfully applied to cells with convex shape. Nevertheless, unfortunately, the method fails in case of specimen with concave surfaces. Here, we propose an effective approach to achieve correct 3D shape measurement that can be extended in case of cells having concave surfaces, thus overcoming the limit of the previous technique. We prove the new procedure for healthy red blood cells (RBCs) (i.e., discocytes) having a concave surface in their central region. Comparative analysis of experimental results with a theoretical 3D geometrical model of RBC is discussed in order to evaluate accuracy of the proposed approach. Finally, we show that the method can be also useful to classify, in terms of morphology, different varieties of RBCs.

  14. Deformation of red blood cells using acoustic radiation forces.

    PubMed

    Mishra, Puja; Hill, Martyn; Glynne-Jones, Peter

    2014-05-01

    Acoustic radiation forces have been used to manipulate cells and bacteria in a number of recent microfluidic applications. The net force on a cell has been subject to careful investigation over a number of decades. We demonstrate that the radiation forces also act to deformcells. An ultrasonic standing wave field is created in a 0.1 mm glass capillary at a frequency of 7.9 MHz. Using osmotically swollen red-blood cells, we show observable deformations up to an aspect ratio of 1.35, comparable to deformations created by optical tweezing. In contrast to optical technologies, ultrasonic devices are potentially capable of deforming thousands of cells simultaneously. We create a finite element model that includes both the acoustic environment of the cell, and a model of the cell membrane subject to forces resulting from the non-linear aspects of the acoustic field. The model is found to give reasonable agreement with the experimental results, and shows that the deformation is the result of variation in an acoustic force that is directed outwards at all points on the cell membrane. We foresee applications in diagnostic devices, and in the possibility of mechanically stimulating cells to promote differentiation and physiological effects.

  15. Chaotic dynamics of red blood cells in oscillating shear flow

    NASA Astrophysics Data System (ADS)

    Bagchi, Prosenjit; Cordasco, Daniel

    2015-11-01

    A 3D computational study of deformable red blood cells in dilute suspension and subject to sinusoidally oscillating shear flow is considered. It is observed that the cell exhibits either a periodic motion or a chaotic motion. In the periodic motion, the cell reverses its orientation either about the flow direction or about the flow gradient, depending on the initial conditions. In certain parameter range, the initial conditions are forgotten and the cells become entrained in the same sequence of horizontal reversals. The chaotic dynamics is characterized by a nonperiodic sequence of horizontal and vertical reversals, and swings. The study provides the first conclusive evidence of the chaotic dynamics of fully deformable cells in oscillating flow using a deterministic numerical model without the introduction of any stochastic noise. An analysis of the chaotic dynamics shows that chaos is only possible in certain frequency bands when the cell membrane can rotate by a certain amount allowing the cells to swing near the maximum shear rate. We make a novel observation that the occurrence of the vertical or horizontal reversal depends only on whether a critical angle, that is independent of the flow frequency, is exceeded at the instant of flow reversal.

  16. Stretching and relaxation of malaria-infected red blood cells.

    PubMed

    Ye, Ting; Phan-Thien, Nhan; Khoo, Boo Cheong; Lim, Chwee Teck

    2013-09-03

    The invasion of red blood cells (RBCs) by malaria parasites is a complex dynamic process, in which the infected RBCs gradually lose their deformability and their ability to recover their original shape is greatly reduced with the maturation of the parasites. In this work, we developed two types of cell model, one with an included parasite, and the other without an included parasite. The former is a representation of real malaria-infected RBCs, in which the parasite is treated as a rigid body. In the latter, where the parasite is absent, the membrane modulus and viscosity are elevated so as to produce the same features present in the parasite model. In both cases, the cell membrane is modeled as a viscoelastic triangular network connected by wormlike chains. We studied the transient behaviors of stretching deformation and shape relaxation of malaria-infected RBCs based on these two models and found that both models can generate results in agreement with those of previously published studies. With the parasite maturation, the shape deformation becomes smaller and smaller due to increasing cell rigidity, whereas the shape relaxation time becomes longer and longer due to the cell's reduced ability to recover its original shape. Copyright © 2013 Biophysical Society. Published by Elsevier Inc. All rights reserved.

  17. Continuum modeling of deformation and aggregation of red blood cells.

    PubMed

    Yoon, Daegeun; You, Donghyun

    2016-07-26

    In order to gain better understanding for rheology of an isolated red blood cell (RBC) and a group of multiple RBCs, new continuum models for describing mechanical properties of cellular structures of an RBC and inter-cellular interactions among multiple RBCs are developed. The viscous property of an RBC membrane, which characterizes dynamic behaviors of an RBC under stress loading and unloading processes, is determined using a generalized Maxwell model. The present model is capable of predicting stress relaxation and stress-strain hysteresis, of which prediction is not possible using the commonly used Kelvin-Voigt model. Nonlinear elasticity of an RBC is determined using the Yeoh hyperelastic material model in a framework of continuum mechanics using finite-element approximation. A novel method to model inter-cellular interactions among multiple adjacent RBCs is also developed. Unlike the previous modeling approaches for aggregation of RBCs, where interaction energy for aggregation is curve-fitted using a Morse-type potential function, the interaction energy is analytically determined. The present aggregation model, therefore, allows us to predict various effects of physical parameters such as the osmotic pressure, the thickness of a glycocalyx layer, the penetration depth, and the permittivity, on the depletion and electrostatic energy among RBCs. Simulations for elongation and recovery deformation of an RBC and for aggregation of multiple RBCs are conducted to evaluate the efficacy of the present continuum modeling methods. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Mechanochemistry of single red blood cells monitored using Raman tweezers.

    PubMed

    Raj, Saurabh; Marro, Mónica; Wojdyla, Michal; Petrov, Dmitri

    2012-04-01

    Two microparticles were biochemically attached to a red blood cell at diametrically opposite parts and held by optical traps allowing to impose deformations. The cell deformation was monitored from the microscopy images. Raman spectra of the cell under tunable deformations were studied. Vibrational spectra analysis at different stretching states was supported with two statistical methods. Principal Component Analysis distinguishes the most prominent changes in spectra while 2D correlation technique monitors the evolution of Raman bands during stretching. The measurements show significant changes in the cell chemical structure with stretching however the changes saturate above 20% of cell deformation. Mechanical deformation of the cell mainly affects the bands corresponding to hemoglobin but contributions from spectrin and membrane proteins can not be excluded. The saturation of bands at higher deformations suggests some structural relaxation that RBC has to undergo to bear extra load. The results confirm widely accepted belief that spectrin released from membrane proteins allows for significant shape changes of the cells. We therefore tentatively suggest that interaction between membrane and cytoskeleton during deformation can be efficiently probed by confocal Raman spectroscopy, in particular via the peak around 1035 cm(-1).

  19. Deformation of red blood cells using acoustic radiation forces

    PubMed Central

    Mishra, Puja; Hill, Martyn; Glynne-Jones, Peter

    2014-01-01

    Acoustic radiation forces have been used to manipulate cells and bacteria in a number of recent microfluidic applications. The net force on a cell has been subject to careful investigation over a number of decades. We demonstrate that the radiation forces also act to deform cells. An ultrasonic standing wave field is created in a 0.1 mm glass capillary at a frequency of 7.9 MHz. Using osmotically swollen red-blood cells, we show observable deformations up to an aspect ratio of 1.35, comparable to deformations created by optical tweezing. In contrast to optical technologies, ultrasonic devices are potentially capable of deforming thousands of cells simultaneously. We create a finite element model that includes both the acoustic environment of the cell, and a model of the cell membrane subject to forces resulting from the non-linear aspects of the acoustic field. The model is found to give reasonable agreement with the experimental results, and shows that the deformation is the result of variation in an acoustic force that is directed outwards at all points on the cell membrane. We foresee applications in diagnostic devices, and in the possibility of mechanically stimulating cells to promote differentiation and physiological effects. PMID:25379070

  20. Mechanical modeling of red blood cells during optical stretching.

    PubMed

    Tan, Youhua; Sun, Dong; Huang, Wenhao

    2010-04-01

    Mechanical properties of red blood cells (RBCs) play an important role in regulating cellular functions. Many recent researches suggest that the cell properties or deformability may be used as a diagnostic indicator for the onset and progression of some human diseases. Although optical stretcher (OS) has emerged as an effective tool to investigate the cell mechanics of RBCs, little is known about the deformation behavior of RBCs in an OS. To address this problem, the mechanical model proposed in our previous work is extended in this paper to describe the mechanical responses of RBCs in the OS. With this model, the mechanical responses, such as the tension distribution, the effect of cell radius, and the deformed cell shapes, can be predicted. It is shown that the results obtained from our mechanical model are in good agreement with the experimental data, which demonstrates the validity of the developed model. Based on the derived model, the mechanical properties of RBCs can be further obtained. In conclusion, this study indicates that the developed mechanical model can be used to predict the deformation responses of RBCs during optical stretching and has potential biomedical applications such as characterizing cell properties and distinguishing abnormal cells from normal ones.

  1. Dynamic modes of red blood cells in oscillatory shear flow.

    PubMed

    Noguchi, Hiroshi

    2010-06-01

    The dynamics of red blood cells (RBCs) in oscillatory shear flow was studied using differential equations of three variables: a shape parameter, the inclination angle θ, and phase angle ϕ of the membrane rotation. In steady shear flow, three types of dynamics occur depending on the shear rate and viscosity ratio. (i) tank-treading (TT): ϕ rotates while the shape and θ oscillate. (ii) tumbling (TB): θ rotates while the shape and ϕ oscillate. (iii) intermediate motion: both ϕ and θ rotate synchronously or intermittently. In oscillatory shear flow, RBCs show various dynamics based on these three motions. For a low shear frequency with zero mean shear rate, a limit-cycle oscillation occurs, based on the TT or TB rotation at a high or low shear amplitude, respectively. This TT-based oscillation well explains recent experiments. In the middle shear amplitude, RBCs show an intermittent or synchronized oscillation. As shear frequency increases, the vesicle oscillation becomes delayed with respect to the shear oscillation. At a high frequency, multiple limit-cycle oscillations coexist. The thermal fluctuations can induce transitions between two orbits at very low shear amplitudes. For a high mean shear rate with small shear oscillation, the shape and θ oscillate in the TT motion but only one attractor exists even at high shear frequencies. The measurement of these oscillatory modes is a promising tool for quantifying the viscoelasticity of RBCs, synthetic capsules, and lipid vesicles.

  2. Dynamic modes of red blood cells in oscillatory shear flow

    NASA Astrophysics Data System (ADS)

    Noguchi, Hiroshi

    2010-06-01

    The dynamics of red blood cells (RBCs) in oscillatory shear flow was studied using differential equations of three variables: a shape parameter, the inclination angle θ , and phase angle ϕ of the membrane rotation. In steady shear flow, three types of dynamics occur depending on the shear rate and viscosity ratio. (i) tank-treading (TT): ϕ rotates while the shape and θ oscillate. (ii) tumbling (TB): θ rotates while the shape and ϕ oscillate. (iii) intermediate motion: both ϕ and θ rotate synchronously or intermittently. In oscillatory shear flow, RBCs show various dynamics based on these three motions. For a low shear frequency with zero mean shear rate, a limit-cycle oscillation occurs, based on the TT or TB rotation at a high or low shear amplitude, respectively. This TT-based oscillation well explains recent experiments. In the middle shear amplitude, RBCs show an intermittent or synchronized oscillation. As shear frequency increases, the vesicle oscillation becomes delayed with respect to the shear oscillation. At a high frequency, multiple limit-cycle oscillations coexist. The thermal fluctuations can induce transitions between two orbits at very low shear amplitudes. For a high mean shear rate with small shear oscillation, the shape and θ oscillate in the TT motion but only one attractor exists even at high shear frequencies. The measurement of these oscillatory modes is a promising tool for quantifying the viscoelasticity of RBCs, synthetic capsules, and lipid vesicles.

  3. Hemoglobin dynamics in red blood cells: correlation to body temperature.

    PubMed

    Stadler, A M; Digel, I; Artmann, G M; Embs, J P; Zaccai, G; Büldt, G

    2008-12-01

    A transition in hemoglobin behavior at close to body temperature has been discovered recently by micropipette aspiration experiments on single red blood cells (RBCs) and circular dichroism spectroscopy on hemoglobin solutions. The transition temperature was directly correlated to the body temperatures of a variety of species. In an exploration of the molecular basis for the transition, we present neutron scattering measurements of the temperature dependence of hemoglobin dynamics in whole human RBCs in vivo. The data reveal a change in the geometry of internal protein motions at 36.9 degrees C, at human body temperature. Above that temperature, amino acid side-chain motions occupy larger volumes than expected from normal temperature dependence, indicating partial unfolding of the protein. Global protein diffusion in RBCs was also measured and the findings compared favorably with theoretical predictions for short-time self-diffusion of noncharged hard-sphere colloids. The results demonstrated that changes in molecular dynamics in the picosecond time range and angstrom length scale might well be connected to a macroscopic effect on whole RBCs that occurs at body temperature.

  4. Diamond Blackfan anemia: a disorder of red blood cell development.

    PubMed

    Ellis, Steven R; Lipton, Jeffrey M

    2008-01-01

    Diamond Blackfan anemia (DBA) is an inherited hypoplastic anemia that typically presents in the first year of life. The genes identified to date that are mutated in DBA encode ribosomal proteins, and in these cases ribosomal protein haploinsufficiency gives rise to the disease. The developmental timing of DBA presentation suggests that the changes in red blood cell production that occur around the time of birth trigger a pathophysiological mechanism, likely linked to defective ribosome synthesis, which precipitates the hematopoietic phenotype. Variable presentation of other clinical phenotypes in DBA patients indicates that other developmental pathways may also be affected by ribosomal protein haploinsufficiency and that the involvement of these pathways is influenced by modifier genes. Understanding the molecular basis for the developmental timing of DBA presentation promises to shed light on a number of baffling features of this disease. This chapter also attempts to demonstrate how the marriage of laboratory and clinical science may enhance each and permit insights into human disease that neither alone can accomplish.

  5. Dynamics of Red Blood Cells through submicronic splenic slits

    NASA Astrophysics Data System (ADS)

    Helfer, Emmanuele; Gambhire, Priya; Atwell, Scott; Bedu, Frederic; Ozerov, Igor; Viallat, Annie; Charrier, Anne; Badens, Catherine; Centre de reference Thalassemie, Badens Team; Physics; Engineering of Living Systems Team

    2016-11-01

    Red Blood Cells (RBCs) are periodically monitored for changes in their deformability by the spleen, and are entrapped and destroyed if unable to pass through the splenic interendothelial slits (IESs). In particular, in sickle cell disease (SCD), where hemoglobin form fibers inside the RBCs, and in hereditary spherocytosis (HS), where RBCs are more spherical and membrane-cytoskekeleton bonds are weakened, the loss of RBC deformability leads to spleen dysfunction. By combining photolithography and anisotropic wet etching techniques, we developed a new on-chip PDMS device with channels replicating the submicronic physiological dimensions of IESs to study the mechanisms of deformation of the RBCs during their passage through these biomimetic slits. For the first time, with HS RBCs, we show the disruption of the links between the RBC membrane and the underlying spectrin network. In the case of SCD RBCs we show the appearance of a tip at the front of the RBC with a longer time relaxation due to the increased cytoplasmic viscosity. This work has been carried out thanks to the support of the A*MIDEX project (n° ANR-11-IDEX-0001-02) funded by the «Investissements d'Avenir». French Government program, managed by ANR.

  6. Red Blood Cell Dysfunction Induced by High-Fat Diet

    PubMed Central

    Unruh, Dusten; Srinivasan, Ramprasad; Benson, Tyler; Haigh, Stephen; Coyle, Danielle; Batra, Neil; Keil, Ryan; Sturm, Robert; Blanco, Victor; Palascak, Mary; Franco, Robert S.; Tong, Wilson; Chatterjee, Tapan; Hui, David Y.; Davidson, W. Sean; Aronow, Bruce J.; Kalfa, Theodosia; Manka, David; Peairs, Abigail; Blomkalns, Andra; Fulton, David J.; Brittain, Julia E.; Weintraub, Neal L.; Bogdanov, Vladimir Y.

    2015-01-01

    Background High-fat diet (HFD) promotes endothelial dysfunction and proinflammatory monocyte activation, which contribute to atherosclerosis in obesity. We investigated whether HFD also induces the dysfunction of red blood cells (RBCs), which serve as a reservoir for chemokines via binding to Duffy antigen receptor for chemokines (DARC). Methods and Results A 60% HFD for 12 weeks, which produced only minor changes in lipid profile in C57/BL6 mice, markedly augmented the levels of monocyte chemoattractant protein-1 bound to RBCs, which in turn stimulated macrophage migration through an endothelial monolayer. Levels of RBC-bound KC were also increased by HFD. These effects of HFD were abolished in DARC−/− mice. In RBCs from HFD-fed wild-type and DARC−/− mice, levels of membrane cholesterol and phosphatidylserine externalization were increased, fostering RBC-macrophage inflammatory interactions and promoting macrophage phagocytosis in vitro. When labeled ex vivo and injected into wild-type mice, RBCs from HFD-fed mice exhibited ≈3-fold increase in splenic uptake. Finally, RBCs from HFD-fed mice induced increased macrophage adhesion to the endothelium when they were incubated with isolated aortic segments, indicating endothelial activation. Conclusions RBC dysfunction, analogous to endothelial dysfunction, occurs early during diet-induced obesity and may serve as a mediator of atherosclerosis. These findings may have implications for the pathogenesis of atherosclerosis in obesity, a worldwide epidemic. PMID:26467254

  7. Functional 20S proteasomes in mature human red blood cells.

    PubMed

    Neelam, Sudha; Kakhniashvili, David G; Wilkens, Stephan; Levene, Stephen D; Goodman, Steven R

    2011-05-01

    The purpose of the present study was to investigate whether functional 20S and/or 26S proteasomes are present within mature human red blood cells (RBCs; depleted of reticulocytes and leukocytes). Double-immunofluorescence confocal microscopy showed the presence of immunoreactive 20S and 19S proteasomal subunit proteins and their partial co-localization within mature RBCs. Proteasomes isolated from mature RBCs displayed 20S activity in vitro; atomic-force and transmission electron microscopy of isolated proteasomes revealed abundant 20S core particles and very few 26S particles. A two-dimensional differential in-gel electrophoresis (2D-DIGE) approach was used to determine if proteasome-dependent protein degradation occurs within mature RBCs. Twenty-eight proteins were identified with altered protein content in response to lactacystin. Seven cytosolic proteins showed an increase and 16 showed a decrease; five membrane proteins showed a decrease. We conclude that the proteins showing increased abundance are either primary or secondary targets of the 20S proteasome and that putatively degraded proteins are secondary targets. Therefore, functional 20S proteasomes exist within mature RBCs. Our study did not detect 26S proteasome activity using the 2D-DIGE approach.

  8. Lytic resistance of fibrin containing red blood cells.

    PubMed

    Wohner, Nikolett; Sótonyi, Péter; Machovich, Raymund; Szabó, László; Tenekedjiev, Kiril; Silva, Marta M C G; Longstaff, Colin; Kolev, Krasimir

    2011-10-01

    Arterial thrombi contain variable amounts of red blood cells (RBCs), which interact with fibrinogen through an eptifibatide-sensitive receptor and modify the structure of fibrin. In this study, we evaluated the modulator role of RBCs in the lytic susceptibility of fibrin. If fibrin is formed at increasing RBC counts, scanning electron microscopy evidenced a decrease in fiber diameter from 150 to 96 nm at 40% (v/v) RBCs, an effect susceptible to eptifibatide inhibition (restoring 140 nm diameter). RBCs prolonged the lysis time in a homogeneous-phase fibrinolytic assay with tissue plasminogen activator (tPA) by up to 22.7±1.6%, but not in the presence of eptifibatide. Confocal laser microscopy using green fluorescent protein-labeled tPA and orange fluorescent fibrin showed that 20% to 40% (v/v) RBCs significantly slowed down the dissolution of the clots. The fluorescent tPA variant did not accumulate on the surface of fibrin containing RBCs at any cell count above 10%. The presence of RBCs in the clot suppressed the tPA-induced plasminogen activation, resulting in 45% less plasmin generated after 30 minutes of activation at 40% (v/v) RBCs. RBCs confer lytic resistance to fibrin resulting from modified fibrin structure and impaired plasminogen activation through a mechanism that involves eptifibatide-sensitive fibrinogen-RBC interactions.

  9. Light scattering by adjacent red blood cells: a mathematical model

    NASA Astrophysics Data System (ADS)

    Uzunoglou, Nikolaos K.; Stamatakos, Georgios; Koutsouris, Dimitrios; Yova-Loukas, Dido M.

    1995-01-01

    Simple approximate scattering theories such as the Rayleigh-Gans theory are not generally applicable to the case of light scattering by red blood cell (RBC) aggregates, including thrombus. This is mainly due to the extremely short distance separating erythrocytes in the aggregates (of the order of 25 nm) as well as to the substantial size of the aggregates. Therefore, in this paper a new mathematical model predicting the electromagnetic field produced by the scattering of a plane electromagnetic wave by a system of two adjacent RBCs is presented. Each RBC is modeled as a homogeneous dielectric ellipsoid of complex index of refraction surrounded by transparent plasma. The relative position and orientation of the ellipsoids are arbitrary. Scattering is formulated in terms of an integral equation which, however, contains two singular kernels. The singular equation is transformed into a pair of nonsingular integral equations for the Fourier transform of the internal field of each RBC. The latter equations are solved by reducing them by quadrature into a matrix equation. The resulting solutions are used to estimate the scattering amplitude. Convergence aspects concerning the numerical calculation of the matrix elements originating from the interaction between the RBCs are also presented.

  10. Influence of space flight on red blood cells.

    PubMed

    Talbot, J M; Fisher, K D

    1986-08-01

    Losses of red blood cell mass (RCM) averaging 10-15% have been observed consistently in astronauts after space flight; postflight recovery of RCM requires 4-6 wk. Although apparently not harmful to the health and effectiveness of crews during uncomplicated flights, decreased RCM could compromise health and performance in the event of illness, injury, or partial malfunction of the life support system. Whether the loss of RCM would worsen or stabilize in missions longer than 7 months is unknown. As a biological response, it is a significant, predictable reaction whose etiology, biological mechanisms, and potential operational significance are inadequately defined. Weightlessness is probably the primary cause; however, contributory factors may include hypokinesia/hypodynamia, bone loss, muscle atrophy, altered hemodynamics, stress, and metabolic disturbances. Space medical specialists consider other possible influences such as hypoxia, hypobaria, radiation, toxic contaminants, and launch and reentry accelerations as less likely factors. Because the data base on loss of RCM is insufficient for the National Aeronautics and Space Administration's space medical responsibilities, the Life Sciences Research Office ad hoc Working Group on Space Anemia suggested research approaches ranging form fundamental topics such as utilization of erythropoietin and oxygen in target organs and cell-cell interactions, through possible splenic and vascular dysfunctions, metabolic disturbances, and inhibitors of erythropoiesis, to methodology and models.

  11. Glutaraldehyde fixation of sodium transport in dog red blood cells

    SciTech Connect

    Parker, J.C.

    1984-11-01

    The large increase in passive Na flux that occurs when dog red blood cells are caused to shrink is amiloride sensitive and inhibited when Cl is replaced by nitrate or thiocyanate. Activation and deactivation of this transport pathway by manipulation of cell volume is reversible. Brief treatment of the cells with 0.01-0.03% glutaraldehyde can cause the shrinkage-activated transporter to become irreversibly activated or inactivated, depending on the volume of the cells at the time of glutaraldehyde exposure. Thus, if glutaraldehyde is applied when the cells are shrunken, the amiloride-sensitive Na transporter is activated and remains so regardless of subsequent alterations in cell volume. If the fixative is applied to swollen cells, no amount of subsequent shrinkage will turn on the Na pathway. In its fixed state, the activated transporter is fully amiloride sensitive, but it is no longer inhibited when Cl is replaced by thiocyanate. The action of glutaraldehyde thus allows one to dissect the response to cell shrinkage into two phases. Activation of the pathway is affected by anions and is not prevented by amiloride. Once activated and fixed, the anion requirement disappears. Amiloride inhibits movement of Na through the activated transporter. These experiments demonstrate how a chemical cross-linking agent may be used to study the functional properties of a regulable transport pathway.

  12. Twisting of Red Blood Cells Entering a Constriction

    NASA Astrophysics Data System (ADS)

    Zeng, Nancy; Ristenpart, William

    2014-11-01

    Most work on the dynamic response of red blood cells (RBCs) to hydrodynamic stress has focused on linear velocity profiles. Relatively little experimental work has examined how individual RBCs respond to pressure driven flow in more complex geometries, such as the flow at the entrance of a capillary. Here, we establish the mechanical behaviors of healthy RBCs undergoing a sudden increase in shear stress at the entrance of a narrow constriction. We pumped RBCs through a constriction in an ex vivo microfluidic device and used high speed video to visualize and track the flow behavior of more than 4,400 RBCs. We show that approximately 85% of RBCs undergo one of four distinct modes of motion: stretching, twisting, tumbling, or rolling. Intriguingly, a plurality of cells (~30%) exhibited twisting (rotation around the major axis parallel to the flow direction), a mechanical behavior that is not typically observed in linear velocity profiles. We examine the mechanical origin of twisting using, as a limiting case, the equations of motion for rigid ellipsoids, and we demonstrate that the observed rotation is qualitatively consistent with rigid body theory.

  13. Smoking and Red Blood Cell Phospholipid Membrane Fatty Acids

    PubMed Central

    Murff, H.J.; Tindle, H.A.; Shrubsole, M.J.; Cai, Q.; Smalley, W.; Milne, G.L.; Swift, L.L.; Ness, R. M.; Zheng, W.

    2016-01-01

    Smoking is associated with lower n-3 long chain polyunsaturated fatty acids (LCPUFA) concentrations; however, limited studies have accounted for dietary PUFA intake or whether tobacco dose or smoking duration influences this association. We measured red blood cell phospholipid (RBC) membrane concentrations of fatty acids in 126 current smokers, 311 former smokers, and 461 never smokers using gas liquid chromatography and tandem mass spectrometry. Smokers had lower RBC membrane percentages of total n-3 LCPUFAs compared to former smokers or never smokers (median percent: 5.46, [interquartile range (IQR) 4.52, 6.28] versus 6.39; [IQR: 5.18, 7.85] versus 6.59; [IQR 5.34, 8.01]) (p < 0.001) and this association remained after adjusting for dietary PUFA intake. Duration of smoking and cigarettes per day were not associated with RBC membrane n-3 LCPUFA differences. Smoking is associated with lower n-3 LCPUFA RBC membrane percentages and this association was not influenced by diet or smoking dose or duration. PMID:27637337

  14. Smoking and red blood cell phospholipid membrane fatty acids.

    PubMed

    Murff, H J; Tindle, H A; Shrubsole, M J; Cai, Q; Smalley, W; Milne, G L; Swift, L L; Ness, R M; Zheng, W

    2016-09-01

    Smoking is associated with lower n-3 long chain polyunsaturated fatty acids (LCPUFA) concentrations; however, limited studies have accounted for dietary PUFA intake or whether tobacco dose or smoking duration influences this association. We measured red blood cell phospholipid (RBC) membrane concentrations of fatty acids in 126 current smokers, 311 former smokers, and 461 never smokers using gas liquid chromatography and tandem mass spectrometry. Smokers had lower RBC membrane percentages of total n-3 LCPUFAs compared to former smokers or never smokers (median percent: 5.46, [interquartile range (IQR) 4.52, 6.28] versus 6.39; [IQR: 5.18, 7.85] versus 6.59; [IQR 5.34, 8.01]) (p<0.001) and this association remained after adjusting for dietary PUFA intake. Duration of smoking and cigarettes per day were not associated with RBC membrane n-3 LCPUFA differences. Smoking is associated with lower n-3 LCPUFA RBC membrane percentages and this association was not influenced by diet or smoking dose or duration. Published by Elsevier Ltd.

  15. Red blood cell lifespan, erythropoiesis and hemoglobin control.

    PubMed

    Kruse, Anja; Uehlinger, Dominik E; Gotch, Frank; Kotanko, Peter; Levin, Nathan W

    2008-01-01

    Erythropoietin (EPO) and iron deficiency as causes of anemia in patients with limited renal function or end-stage renal disease are well addressed. The concomitant impairment of red blood cell (RBC) survival has been largely neglected. Properties of the uremic environment like inflammation, increased oxidative stress and uremic toxins seem to be responsible for the premature changes in RBC membrane and cytoskeleton. The exposure of antigenic sites and breakdown of the phosphatidylserine asymmetry promote RBC phagocytosis. While the individual response to treatment with EPO-stimulating agents (ESA) depends on both the RBC's lifespan and the production rate, uniform dosing algorithms do not meet that demand. The clinical use of mathematical models predicting ESA-induced changes in hematocrit might be greatly improved once independent estimates of RBC production rate and/or lifespan become available, thus making the concomitant estimation of both parameters unnecessary. Since heme breakdown by the hemoxygenase pathway results in carbon monoxide (CO) which is exhaled, a simple CO breath test has been used to calculate hemoglobin turnover and therefore RBC survival and lifespan. Future research will have to be done to validate and implement this method in patients with kidney failure. This will result in new insights into RBC kinetics in renal patients. Eventually, these findings are expected to improve our understanding of the hemoglobin variability in response to ESA.

  16. The heritability of hemolysis in stored human red blood cells

    PubMed Central

    van ‘t Erve, Thomas J.; Wagner, Brett A.; Martin, Sean M.; Knudson, C. Michael; Blendowski, Robyn; Keaton, Mignon; Holt, Tracy; Hess, John R.; Buettner, Garry R.; Ryckman, Kelli K.; Darbro, Benjamin W.; Murray, Jeffrey C.; Raife, Thomas J.

    2015-01-01

    Background The transfusion of red blood cells (RBCs) with maximum therapeutic efficacy is a major goal in transfusion medicine. One of the criteria used in determining stored RBC quality is end of storage hemolysis. Between donors, a wide range of hemolysis is observed under identical storage conditions. Here, a potential mechanism for this wide range is investigated. We hypothesize that the magnitude of hemolysis is a heritable trait. Also, we investigated correlations between hemolysis and RBC metabolites; this will establish pathways influencing hemolysis as future targets for genetic analysis. Study Design and Methods Units of RBCs from identical and non-identical twins were collected and stored under standard conditions for 56 days. Hemolysis, ATP, and total glutathione were measured throughout storage. Non-targeted metabolic analyses were performed on RBCs that had been stored for 28 days. Heritability was determined by comparing values between identical and non-identical twins. Results Hemolysis was found to be heritable (mean >45 %) throughout the storage period. Correlations were observed between hemolysis and metabolites from the amino acid, sugar, and purine metabolism, lipid metabolism and transport, and glycolysis pathways. Three metabolites also exhibited heritability (> 20%). No correlation was found with ATP or total glutathione. Conclusion The susceptibility of RBCs to lysis during storage is partly determined by inheritance. We have also uncovered several pathways that are candidate targets for future genome wide association studies. These findings will aid in the design of better storage solutions and the development of donor screening tools that minimize hemolysis during storage. PMID:25644965

  17. Imaging red blood cell dynamics by quantitative phase microscopy.

    PubMed

    Popescu, Gabriel; Park, YoungKeun; Choi, Wonshik; Dasari, Ramachandra R; Feld, Michael S; Badizadegan, Kamran

    2008-01-01

    Red blood cells (RBCs) play a crucial role in health and disease, and structural and mechanical abnormalities of these cells have been associated with important disorders such as Sickle cell disease and hereditary cytoskeletal abnormalities. Although several experimental methods exist for analysis of RBC mechanical properties, optical methods stand out as they enable collecting mechanical and dynamic data from live cells without physical contact and without the need for exogenous contrast agents. In this report, we present quantitative phase microscopy techniques that enable imaging RBC membrane fluctuations with nanometer sensitivity at arbitrary time scales from milliseconds to hours. We further provide a theoretical framework for extraction of membrane mechanical and dynamical properties using time series of quantitative phase images. Finally, we present an experimental approach to extend quantitative phase imaging to 3-dimensional space using tomographic methods. By providing non-invasive methods for imaging mechanics of live cells, these novel techniques provide an opportunity for high-throughput analysis and study of RBC mechanical properties in health and disease.

  18. Modeling of Red Blood Cells and Related Spleen Function

    NASA Astrophysics Data System (ADS)

    Peng, Zhangli; Pivkin, Igor; Dao, Ming

    2011-11-01

    A key function of the spleen is to clear red blood cells (RBCs) with abnormal mechanical properties from the circulation. These abnormal mechanical properties may be due to RBC aging or RBC diseases, e.g., malaria and sickle cell anemia. Specifically, 10% of RBCs passing through the spleen are forced to squeeze into the narrow slits between the endothelial cells, and stiffer cells which get stuck are killed and digested by macrophages. To investigate this important physiological process, we employ three different approaches to study RBCs passage through these small slits, including analytical theory, Dissipative Particle Dynamics (DPD) simulation and Multiscale Finite Element Method (MS-FEM). By applying the analytical theory, we estimate the critical limiting geometries RBCs can pass. By using the DPD method, we study the full fluid-structure interaction problem, and compute RBC deformation under different pressure gradients. By employing the MS-FEM approach, we model the lipid bilayer and the cytoskeleton as two distinct layers, and focus on the cytoskeleton deformation and the bilayer-skeleton interaction force at the molecular level. Finally the results of these three approaches are compared to each other and correlated to the experimental observations.

  19. Hemoglobin Dynamics in Red Blood Cells: Correlation to Body Temperature

    PubMed Central

    Stadler, A. M.; Digel, I.; Artmann, G. M.; Embs, J. P.; Zaccai, G.; Büldt, G.

    2008-01-01

    A transition in hemoglobin behavior at close to body temperature has been discovered recently by micropipette aspiration experiments on single red blood cells (RBCs) and circular dichroism spectroscopy on hemoglobin solutions. The transition temperature was directly correlated to the body temperatures of a variety of species. In an exploration of the molecular basis for the transition, we present neutron scattering measurements of the temperature dependence of hemoglobin dynamics in whole human RBCs in vivo. The data reveal a change in the geometry of internal protein motions at 36.9°C, at human body temperature. Above that temperature, amino acid side-chain motions occupy larger volumes than expected from normal temperature dependence, indicating partial unfolding of the protein. Global protein diffusion in RBCs was also measured and the findings compared favorably with theoretical predictions for short-time self-diffusion of noncharged hard-sphere colloids. The results demonstrated that changes in molecular dynamics in the picosecond time range and angstrom length scale might well be connected to a macroscopic effect on whole RBCs that occurs at body temperature. PMID:18708462

  20. A multiscale model for red blood cell mechanics.

    PubMed

    Hartmann, Dirk

    2010-02-01

    The objective of this article is the derivation of a continuum model for mechanics of red blood cells via multiscale analysis. On the microscopic level, we consider realistic discrete models in terms of energy functionals defined on networks/lattices. Using concepts of Gamma-convergence, convergence results as well as explicit homogenisation formulae are derived. Based on a characterisation via energy functionals, appropriate macroscopic stress-strain relationships (constitutive equations) can be determined. Further, mechanical moduli of the derived macroscopic continuum model are directly related to microscopic moduli. As a test case we consider optical tweezers experiments, one of the most common experiments to study mechanical properties of cells. Our simulations of the derived continuum model are based on finite element methods and account explicitly for membrane mechanics and its coupling with bulk mechanics. Since the discretisation of the continuum model can be chosen freely, rather than it is given by the topology of the microscopic cytoskeletal network, the approach allows a significant reduction of computational efforts. Our approach is highly flexible and can be generalised to many other cell models, also including biochemical control.

  1. Red cell exchange to mitigate a delayed hemolytic transfusion reaction in a patient transfused with incompatible red blood cells.

    PubMed

    Irani, Mehraboon S; Karafin, Matthew S; Ernster, Luke

    2017-02-01

    A red cell exchange was performed to prevent a potentially fatal hemolytic transfusion reaction in a patient with anti-e who was transfused with e-antigen unscreened red blood cells during liver transplant surgery. A 64-year-old woman with cirrhosis due to hepatitis C was scheduled to receive a liver transplant. She had a previously documented anti-e, an antibody to the Rh(e)-antigen that is known to cause delayed hemolytic transfusion reactions. Pre-operatively and intra-operatively, she had massive hemorrhage which required transfusion of 34 e-antigen unscreened red blood cells (RBCs) most of which were incompatible. The hemoglobin dropped from 9.1 g/dL on post-operative day (POD)1 to 6.6 g/dL on POD6, with no evidence of blood loss. The bilirubin also increased from 5.0 mg/dL on POD 1 to 11.0 mg/dL on POD 6. As she was also becoming more hemodynamically unstable, a red cell exchange with 10 units of e-negative RBCs was performed on POD 6. She improved clinically and was extubated the following day. A few residual transfused e-positive red cells were detected after the red cell exchange until POD 13. This case illustrates how a red cell exchange can mitigate the potentially harmful effects of a delayed hemolytic transfusion reaction caused by red cell antibodies. With massive intraoperative blood loss it may not be possible to have antigen-negative RBCs immediately available, particularly for the e-antigen, which is present in 98% of the donor population. The ability to perform such a procedure may be life-saving in such patients. J. Clin. Apheresis 32:59-61, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  2. Elevated red blood cell distribution width is associated with intrahepatic cholestasis of pregnancy.

    PubMed

    Vural Yilmaz, Zehra; Gencosmanoglu Turkmen, Gulenay; Daglar, Korkut; Yılmaz, Elif; Kara, Ozgur; Uygur, Dilek

    2017-01-01

    Intrahepatic cholestasis of pregnancy is the most common pregnancy specific liver disease and related with adverse maternal and perinatal outcome. Red blood cell distribution width, an anisocytosis marker in a complete blood count, has been used as an inflammation marker in various diseases. However the association of red blood cell distribution width with intrahepatic cholestasis of pregnancy is unknown. We aimed to evaluate the relationship between red blood cell distribution width and intrahepatic cholestasis of pregnancy. Ninety pregnant women with intrahepatic cholestasis of pregnancy and ninety healthy pregnant women were included in the study. Their clinical and laboratory characteristics including red blood cell distribution width, liver function tests, fasting and postprandial bile acid concentrations were analyzed. Serum red blood cell distribution width cell levels were significantly higher in pregnants with intrahepatic cholestasis of pregnancy than healthy pregnants. We also demonstrated that red blood cell distribution Width levels were higher in severe disease than mild disease and was significantly correlated with fasting and postprandial bile acid concentration in intrahepatic cholestasis of pregnancy group. Our study showed that red blood cell distribution width, an easy and inexpensive marker; were associated with intrahepatic cholestasis of pregnancy and can be used as a diagnostic and prognostic marker in intrahepatic cholestasis of pregnancy.

  3. Red Blood Cell Volume, Plasma Volume and Total Blood Volume in Healthy Elderly Men and Women Aged 64 to 100

    DTIC Science & Technology

    2007-11-02

    had an adeguate oxygen supply to the tissues. The deficiency in red blood cell volume in our elderly subjects was consistent with an adaptive and... ELDERLY MEN AND WOMEN AGED 64 TO 100 BY C.R. VALERI, L.E. PIVACEK, H. SIEBENS, and M.D. ALTSCHULE NAVAL BLOOD RESEARCH LABORATORY BOSTON...TITLE (and Submit) RED BLOOD CELL VOLUME, PLASMA VOLUME AND TOTAL BLOOD VOLUME IN HEALTHY ELDERLY MEN AND WOMEN AGED 64 TO 100 7. AUTHORf»J C

  4. An innovative shape equation to quantify the morphological characteristics of parasitized red blood cells by Plasmodium falciparum and Plasmodium vivax.

    PubMed

    Karimi, Alireza; Navidbakhsh, Mahdi; Motevalli Haghi, Afsaneh; Faghihi, Shahab

    2013-04-01

    The morphology of red blood cells is affected significantly during maturation of malaria parasites, Plasmodium falciparum and Plasmodium vivax. A novel shape equation is presented that defines shape of parasitized red blood cells by P. falciparum (Pf-red blood cells) and P. vivax (Pv-red blood cells) at four stages of infection. The Giemsa-stained thin blood films are prepared using blood samples collected from healthy donors, patients having P. falciparum and P. vivax malaria. The diameter and thickness of healthy red blood cells plus Pf-red blood cells and Pv-red blood cells at each stage of infection are measured from their optical images using Olysia and Scanning Probe Image Processor softwares, respectively. Using diameters and thicknesses of parasitized red blood cells, a shape equation is fitted and relative two-dimensional shapes are plotted using MATHEMATICA. The shape of Pf-red blood cell drastically changes at ring stage as its thickness increases by 82%, while Pv-red blood cell remains biconcave (30% increase in thickness). By trophozoite and subsequent schizont stage, the Pf-red blood cell entirely loses its biconcave shape and becomes near spherical (diameter and thickness of ~8 µm). The Pv-red blood cell remains biconcave throughout the parasite development even though its volume increases. These results could have practical use for faster diagnosis, prediction, and treatment of human malaria and sickle-cell diseases.

  5. Temperature-dependent haemolytic propensity of CPDA-1 stored red blood cells vs whole blood - Red cell fragility as donor signature on blood units.

    PubMed

    Tzounakas, Vassilis L; Anastasiadi, Alkmini T; Karadimas, Dimitrios G; Zeqo, Redisa A; Georgatzakou, Hara T; Pappa, Olga D; Papatzitze, Olga A; Stamoulis, Konstantinos E; Papassideri, Issidora S; Antonelou, Marianna H; Kriebardis, Anastasios G

    2017-09-01

    To preserve cellular integrity and avoid bacterial growth, storage and transfer of blood and blood products follow strict guidelines in terms of temperature control. We evaluated the impact of ineligible warming of whole blood donations on the quality of blood components. One-hundred and twenty units of whole blood (WB) from eligible blood donors were collected in CPDA-1 and stored at 4±2 °C. During shipment to the blood processing centre, a gradual warming up to 17 °C was recorded within a period of less than eight hours. The warmed units were processed to packed red blood cells (PRBCs) or stored as WB units at 4±2 °C. In-bag haemolysis, osmotic fragility (mean corpuscular fragility, MCF) and bacterial growth were assessed in blood and blood components throughout the storage period. Normal basal and early storage levels of haemolysis were recorded in both PRBC and WB units. Thereafter, PRBCs exhibited higher average in-bag haemolysis and MCF index compared to the WB units throughout the storage. Moreover, 14.3 and 52.4% of the PRBC units exceeded the upper permissible limit of 0.8% haemolysis at the middle (1.220±0.269%) or late (1.754±0.866%) storage period, respectively. MCF index was similar in all PRBCs at the middle of storage but significantly lower in the non-haemolysed compared to the haemolysed units of PRBCs on the last days. The fragility of stored RBCs was proportional to the donor-related values of day 2 samples (r=0.861, p<10(-32)). In the qualified PRBCs, MCF was correlated with haemolysis at every time point of the storage period (r=0.332, p<0.050). Bacterial growth was detected by blood culture in two units of PRBCs. Transient, gradient warming of whole blood from 4 to 17 °C led to increased incidence of in-bag haemolysis in PRBC but not in WB units. Haemolysis is a multi-parametric phenotype of stored blood, and MCF is a donor-related and highly dynamic measure that can, in part, predict the storage lesion.

  6. Scanning electron microscopy of glomerular and non glomerular red blood cells.

    PubMed

    Fassett, R G; Horgan, B; Gove, D; Mathew, T H

    1983-07-01

    Phase contrast microscopic examination of the urine has been recently shown to be of value in predicting whether hematuria is due to glomerulonephritis or lesions of the lower urinary tract. Glomerular red cells show variations in size and shape and have distorted surfaces. Non glomerular red cells are uniform in size and shape and have smooth surfaces. Scanning electron microscopy was performed on urine sediment containing either glomerular or non glomerular red cells to better define their surface characteristics. Glomerular red cells exhibited a variety of forms, most cells having lumpy projections from the surface, some showing fragmentation of the membrane and others showing gross distortion. In contrast non glomerular red cells show smooth surfaces and usually maintain the normal biconcave disc shape of peripheral red blood cells. Scanning electron microscopy can better define surface structural abnormalities of urinary glomerular and non glomerular red blood cells.

  7. Separation of White Blood Cells from Red Blood Cells in a Microfabricated Lattice

    NASA Astrophysics Data System (ADS)

    Austin, Robert H.; Chan, Shirley S.

    1996-03-01

    Leukocytes (WBCs) are relatively rare in a healthy person: approximately 1 out of every thousand cells in the blood are WBCs, the rest are predominantly the un-nucleated erythrocytes (RBCs). Chemotactic control of WBC invasion of small openings (one micron or less) is a critical element in understanding, and perhaps someday controlling, the invasive and lethal transformation of WBCs in leukemia. Quantitative study and understanding of the physical phenomena involved in chemotaxis requires the ability to both capture from blood the relatively rare WBCs and then to challenge them with a precise array of variable sized openings in the presence of a known chemical gradient. We have recently been able to show that a suitably chosen opening in microlithographically constructed array structures can with 100% efficiency sort rare white blood cells from red blood cells and hold them for optical observation under a transparent glass lid. We have developed sensitive fluorescence and dark-field techniques to observe the signal transduction and motile response to both hydrodynamic shear fields and chemotactic patterns. Videos of this work will be shown.

  8. A smart core-sheath nanofiber that captures and releases red blood cells from the blood.

    PubMed

    Shi, Q; Hou, J; Zhao, C; Xin, Z; Jin, J; Li, C; Wong, S-C; Yin, J

    2016-01-28

    A smart core-sheath nanofiber for non-adherent cell capture and release is demonstrated. The nanofibers are fabricated by single-spinneret electrospinning of poly(N-isopropylacrylamide) (PNIPAAm), polycaprolactone (PCL) and nattokinase (NK) solution blends. The self-assembly of PNIPAAm and PCL blends during the electrospinning generates the core-sheath PCL/PNIPAAm nanofibers with PNIPAAm as the sheath. The PNIPAAm-based core-sheath nanofibers are switchable between hydrophobicity and hydrophilicity with temperature change and enhance stability in the blood. When the nanofibers come in contact with blood, the NK is released from the nanofibers to resist platelet adhesion on the nanofiber surface, facilitating the direct capture and isolation of red blood cells (RBCs) from the blood above phase-transition temperature of PNIPAAm. Meanwhile, the captured RBCs are readily released from the nanofibers with temperature stimuli in an undamaged manner. The release efficiency of up to 100% is obtained while maintaining cellular integrity and function. This work presents promising nanofibers to effectively capture non-adherent cells and release for subsequent molecular analysis and diagnosis of single cells.

  9. Pleomorphic Structures in Human Blood Are Red Blood Cell-Derived Microparticles, Not Bacteria

    PubMed Central

    Mitchell, Adam J.; Gray, Warren D.; Schroeder, Max; Yi, Hong; Taylor, Jeannette V.; Dillard, Rebecca S.; Ke, Zunlong; Wright, Elizabeth R.; Stephens, David; Roback, John D.; Searles, Charles D.

    2016-01-01

    Background Red blood cell (RBC) transfusions are a common, life-saving therapy for many patients, but they have also been associated with poor clinical outcomes. We identified unusual, pleomorphic structures in human RBC transfusion units by negative-stain electron microscopy that appeared identical to those previously reported to be bacteria in healthy human blood samples. The presence of viable, replicating bacteria in stored blood could explain poor outcomes in transfusion recipients and have major implications for transfusion medicine. Here, we investigated the possibility that these structures were bacteria. Results Flow cytometry, miRNA analysis, protein analysis, and additional electron microscopy studies strongly indicated that the pleomorphic structures in the supernatant of stored RBCs were RBC-derived microparticles (RMPs). Bacterial 16S rDNA PCR amplified from these samples were sequenced and was found to be highly similar to species that are known to commonly contaminate laboratory reagents. Conclusions These studies suggest that pleomorphic structures identified in human blood are RMPs and not bacteria, and they provide an example in which laboratory contaminants may can mislead investigators. PMID:27760197

  10. Pleomorphic Structures in Human Blood Are Red Blood Cell-Derived Microparticles, Not Bacteria.

    PubMed

    Mitchell, Adam J; Gray, Warren D; Schroeder, Max; Yi, Hong; Taylor, Jeannette V; Dillard, Rebecca S; Ke, Zunlong; Wright, Elizabeth R; Stephens, David; Roback, John D; Searles, Charles D

    2016-01-01

    Red blood cell (RBC) transfusions are a common, life-saving therapy for many patients, but they have also been associated with poor clinical outcomes. We identified unusual, pleomorphic structures in human RBC transfusion units by negative-stain electron microscopy that appeared identical to those previously reported to be bacteria in healthy human blood samples. The presence of viable, replicating bacteria in stored blood could explain poor outcomes in transfusion recipients and have major implications for transfusion medicine. Here, we investigated the possibility that these structures were bacteria. Flow cytometry, miRNA analysis, protein analysis, and additional electron microscopy studies strongly indicated that the pleomorphic structures in the supernatant of stored RBCs were RBC-derived microparticles (RMPs). Bacterial 16S rDNA PCR amplified from these samples were sequenced and was found to be highly similar to species that are known to commonly contaminate laboratory reagents. These studies suggest that pleomorphic structures identified in human blood are RMPs and not bacteria, and they provide an example in which laboratory contaminants may can mislead investigators.

  11. Blood banking-induced alteration of red blood cell oxygen release ability

    PubMed Central

    Li, Yaojin; Xiong, Yanlian; Wang, Ruofeng; Tang, Fuzhou; Wang, Xiang

    2016-01-01

    Background Current blood banking procedures may not fully preserve red blood cell (RBC) function during storage, contributing to the decrease of RBC oxygen release ability. This study was undertaken to evaluate the impact of routine cold storage on RBC oxygen release ability. Materials and methods RBC units were collected from healthy donors and each unit was split into two parts (whole blood and suspended RBC) to exclude possible donor variability. Oxygen dissociation measurements were performed on blood units stored at 4 °C during a 5-week period. 2,3-diphosphoglycerate levels and fluorescent micrographs of erythrocyte band 3 were also analysed. Results P50 and oxygen release capacity decreased rapidly during the first 3 weeks, and then did not change significantly. In contrast, the kinetic properties (PO2-t curve and T*50) of oxygen release changed slowly during the first 3 weeks of storage, but then decreased significantly in the last 2 weeks. 2,3-diphosphoglycerate decreased quickly during the first 3 weeks of storage to almost undetectable levels. Band 3 aggregated significantly during the last 2 weeks of storage. Discussion RBC oxygen release ability appears to be sensitive to routine cold storage. The thermodynamic characteristics of RBC oxygen release ability changed mainly in the first 3 weeks of storage, due to the decrease of 2,3-diphosphoglycerate, whereas the kinetic characteristics of RBC oxygen release ability decreased significantly at the end of storage, probably affected by alterations of band 3. PMID:26674824

  12. Blood banking-induced alteration of red blood cell oxygen release ability.

    PubMed

    Li, Yaojin; Xiong, Yanlian; Wang, Ruofeng; Tang, Fuzhou; Wang, Xiang

    2016-05-01

    Current blood banking procedures may not fully preserve red blood cell (RBC) function during storage, contributing to the decrease of RBC oxygen release ability. This study was undertaken to evaluate the impact of routine cold storage on RBC oxygen release ability. RBC units were collected from healthy donors and each unit was split into two parts (whole blood and suspended RBC) to exclude possible donor variability. Oxygen dissociation measurements were performed on blood units stored at 4 °C during a 5-week period. 2,3-diphosphoglycerate levels and fluorescent micrographs of erythrocyte band 3 were also analysed. P50 and oxygen release capacity decreased rapidly during the first 3 weeks, and then did not change significantly. In contrast, the kinetic properties (PO2-t curve and T*50) of oxygen release changed slowly during the first 3 weeks of storage, but then decreased significantly in the last 2 weeks. 2,3-diphosphoglycerate decreased quickly during the first 3 weeks of storage to almost undetectable levels. Band 3 aggregated significantly during the last 2 weeks of storage. RBC oxygen release ability appears to be sensitive to routine cold storage. The thermodynamic characteristics of RBC oxygen release ability changed mainly in the first 3 weeks of storage, due to the decrease of 2,3-diphosphoglycerate, whereas the kinetic characteristics of RBC oxygen release ability decreased significantly at the end of storage, probably affected by alterations of band 3.

  13. Effect of red blood cell rigidity on tumor blood flow: increase in viscous resistance during hyperglycemia.

    PubMed

    Sevick, E M; Jain, R K

    1991-05-15

    Elevated glucose level and low pH have been shown to increase red blood cell (RBC) rigidity. This increased rigidity has been proposed as one factor which mediates the tumor blood flow (TBF) reduction during hyperglycemia by (a) causing RBC entrapment and hence increasing geometric resistance and (b) increasing viscous resistance to blood flow. However, due to the inability to measure these resistances in vivo in tumors directly, the relative contribution of RBC rigidity in TBF reduction has not been quantified. In the present study, blood flow resistance was measured in "tissue-isolated" mammary adenocarcinoma R3230AC perfused ex vivo with (a) normally deformable, (b) glutaraldehyde-hardened, and (c) glucose-incubated RBC suspensions. Flow resistance measured during tumor perfusion with Krebs-Henseleit buffer prior to and following perfusion with the glutaraldehyde-hardened RBC suspensions showed no significant change, suggesting constant geometric resistance and lack of RBC entrapment. Instead, our measurements indicated increased viscous resistance with loss of deformability due to glutaraldehyde and glucose incubation even though glucose incubation did not significantly alter the apparent blood viscosity measured in vitro. Thus, the TBF reduction during hyperglycemia may be due to subtle changes in RBC deformability. These results suggest the development of strategies to increase the delivery of drugs or oxygen must take into account any changes in intratumor viscous resistance. For example, the increase in the oxygen-carrying capacity of blood using RBC transfusion or fluorocarbon emulsions may be offset by the increase in viscous resistance and the corresponding reduction in TBF.

  14. Poly-N-acetyl glucosamine-mediated red blood cell interactions.

    PubMed

    Thatte, Hemant S; Zagarins, Sofija E; Amiji, Mansoor; Khuri, Shukri F

    2004-07-01

    Investigations were performed to assess the effect of poly-N-acetyl glucosamine (p-GlcNAc) fiber slurry-mediated hemostasis by interactions with red blood cells. Red blood cell aggregation studies were performed using test material-coated microscope slides and multiphoton microscopic measurements. Enzymatic removal of red blood cell surface proteins was achieved using trypsin and neuraminidase treatment. Zeta-potential measurements (surface charge) were performed. Red blood cells interact directly with poly-N-acetyl glucosamine polymers through ionic interactions and cell-surface proteins. The effective concentration of poly-N-acetyl glucosamine fiber material for 50% red blood cell aggregation was 0.28 mg/mL. The p-GlcNAc beta-configuration fibers and an alpha-configuration structural modification of the fibers both produced maximal responses because of their zeta-potentials, whereas other chemically modified p-GlcNAcs and chitosans were ineffective. Poly-N-acetyl glucosamine-induced red blood cell aggregation is mediated by interactions with red blood cell surface charges.

  15. Red Blood Cell Susceptibility to Pneumolysin: CORRELATION WITH MEMBRANE BIOCHEMICAL AND PHYSICAL PROPERTIES.

    PubMed

    Bokori-Brown, Monika; Petrov, Peter G; Khafaji, Mawya A; Mughal, Muhammad K; Naylor, Claire E; Shore, Angela C; Gooding, Kim M; Casanova, Francesco; Mitchell, Tim J; Titball, Richard W; Winlove, C Peter

    2016-05-06

    This study investigated the effect of the biochemical and biophysical properties of the plasma membrane as well as membrane morphology on the susceptibility of human red blood cells to the cholesterol-dependent cytolysin pneumolysin, a key virulence factor of Streptococcus pneumoniae, using single cell studies. We show a correlation between the physical properties of the membrane (bending rigidity and surface and dipole electrostatic potentials) and the susceptibility of red blood cells to pneumolysin-induced hemolysis. We demonstrate that biochemical modifications of the membrane induced by oxidative stress, lipid scrambling, and artificial cell aging modulate the cell response to the toxin. We provide evidence that the diversity of response to pneumolysin in diabetic red blood cells correlates with levels of glycated hemoglobin and that the mechanical properties of the red blood cell plasma membrane are altered in diabetes. Finally, we show that diabetic red blood cells are more resistant to pneumolysin and the related toxin perfringolysin O relative to healthy red blood cells. Taken together, these studies indicate that the diversity of cell response to pneumolysin within a population of human red blood cells is influenced by the biophysical and biochemical status of the plasma membrane and the chemical and/or oxidative stress pre-history of the cell.

  16. On the shape memory of red blood cells

    NASA Astrophysics Data System (ADS)

    Cordasco, Daniel; Bagchi, Prosenjit

    2017-04-01

    Red blood cells (RBCs) undergo remarkably large deformations when subjected to external forces but return to their biconcave discoid resting shape as the forces are withdrawn. In many experiments, such as when RBCs are subjected to a shear flow and undergo the tank-treading motion, the membrane elements are also displaced from their original (resting) locations along the cell surface with respect to the cell axis, in addition to the cell being deformed. A shape memory is said to exist if after the flow is stopped the RBC regains its biconcave shape and the membrane elements also return to their original locations. The shape memory of RBCs was demonstrated by Fischer ["Shape memory of human red blood cells," Biophys. J. 86, 3304-3313 (2004)] using shear flow go-and-stop experiments. Optical tweezer and micropipette based stretch-relaxation experiments do not reveal the complete shape memory because while the RBC may be deformed, the membrane elements are not significantly displaced from their original locations with respect to the cell axis. Here we present the first three-dimensional computational study predicting the complete shape memory of RBCs using shear flow go-and-stop simulations. The influence of different parameters, namely, membrane shear elasticity and bending rigidity, membrane viscosity, cytoplasmic and suspending fluid viscosity, as well as different stress-free states of the RBC is studied. For all cases, the RBCs always exhibit shape memory. The complete recovery of the RBC in shear flow go-and-stop simulations occurs over a time that is orders of magnitude longer than that for optical tweezer and micropipette based relaxations. The response is also observed to be more complex and composed of widely disparate time scales as opposed to only one time scale that characterizes the optical tweezer and micropipette based relaxations. We observe that the recovery occurs in three phases: a rapid compression of the RBC immediately after the flow is stopped

  17. Targeted erythropoietin selectively stimulates red blood cell expansion in vivo

    PubMed Central

    Burrill, Devin R.; Vernet, Andyna; Collins, James J.; Silver, Pamela A.; Way, Jeffrey C.

    2016-01-01

    The design of cell-targeted protein therapeutics can be informed by natural protein–protein interactions that use cooperative physical contacts to achieve cell type specificity. Here we applied this approach in vivo to the anemia drug erythropoietin (EPO), to direct its activity to EPO receptors (EPO-Rs) on red blood cell (RBC) precursors and prevent interaction with EPO-Rs on nonerythroid cells, such as platelets. Our engineered EPO molecule was mutated to weaken its affinity for EPO-R, but its avidity for RBC precursors was rescued via tethering to an antibody fragment that specifically binds the human RBC marker glycophorin A (huGYPA). We systematically tested the impact of these engineering steps on in vivo markers of efficacy, side effects, and pharmacokinetics. huGYPA transgenic mice dosed with targeted EPO exhibited elevated RBC levels, with only minimal platelet effects. This in vivo selectivity depended on the weakening EPO mutation, fusion to the RBC-specific antibody, and expression of huGYPA. The terminal plasma half-life of targeted EPO was ∼28.3 h in transgenic mice vs. ∼15.5 h in nontransgenic mice, indicating that huGYPA on mature RBCs acted as a significant drug sink but did not inhibit efficacy. In a therapeutic context, our targeting approach may allow higher restorative doses of EPO without platelet-mediated side effects, and also may improve drug pharmacokinetics. These results demonstrate how rational drug design can improve in vivo specificity, with potential application to diverse protein therapeutics. PMID:27114509

  18. Microvascular response to red blood cell transfusion in trauma patients.

    PubMed

    Weinberg, Jordan A; MacLennan, Paul A; Vandromme-Cusick, Marianne J; Angotti, Jonathan M; Magnotti, Louis J; Kerby, Jeffrey D; Rue, Loring W; Barnum, Scott R; Patel, Rakesh P

    2012-03-01

    Trauma patients are often transfused allogeneic red blood cells (RBCs) in an effort to augment tissue oxygen delivery. However, the effect of RBC transfusion on microvascular perfusion in this patient population is not well understood. To this end, we investigated the effect of RBC transfusion on sublingual microvascular perfusion in trauma patients. Sublingual microcirculation was imaged at bedside with a sidestream dark-field illumination microscope before and after transfusion of one RBC unit in hemodynamically stable, anemic trauma patients. The perfused proportion of capillaries (PPC) before and after transfusion was determined, and the percent change in capillary perfusion following transfusion (ΔPPC) calculated. Sublingual microcirculation was observed in 30 patients. Mean age was 47 (SD, 21) years, mean Injury Severity Score was 29 (SD, 16), and mean pretransfusion hemoglobin was 7.5 (SD, 0.9) g/dL. No patients had a mean arterial pressure of less than 65 mmHg (mean, 89 [SD, 17] mmHg) or lactate of greater than 2.5 mmol/L (mean, 1.1 [SD, 0.3] mmol/L). Following transfusion, ΔPPC ranged from +68% to -36% and was found to inversely correlate significantly with pretransfusion PPC (Spearman r = -0.63, P = 0.0002). Pretransfusion PPC may be selectively deranged in otherwise stable trauma patients. Patients with relatively altered baseline PPC tend to demonstrate improvement in perfusion following transfusion, whereas those with relatively normal perfusion at baseline tend to demonstrate either no change or, in fact, a decline in PPC. Bedside sublingual imaging may have the potential to detect subtle perfusion defects and ultimately inform clinical decision making with respect to transfusion.

  19. Microvascular Response to Red Blood Cell Transfusion in Trauma Patients

    PubMed Central

    Weinberg, Jordan A.; MacLennan, Paul A.; Vandromme–Cusick, Marianne J.; Angotti, Jonathan M.; Magnotti, Louis J.; Kerby, Jeffrey D.; Rue, Loring W.; Barnum, Scott R.; Patel, Rakesh P.

    2014-01-01

    Background Trauma patients are often transfused allogeneic red blood cells (RBCs) in an effort to augment tissue oxygen delivery. However, the effect of RBC transfusion on microvascular perfusion in this patient population is not well understood. To this end, we investigated the effect of RBC transfusion on sublingual microvascular perfusion in trauma patients. Methods Sublingual microcirculation was imaged at bedside with a sidestream dark field illumination microscope before and after transfusion of one RBC unit in hemodynamically stable, anemic trauma patients. The proportion of perfused capillaries (PPC) pre- and post-transfusion was determined, and the percent change in capillary perfusion following transfusion (ΔPPC) calculated. Results Sublingual microcirculation was observed in 30 patients. Mean age was 47 (SD=21), mean ISS was 29 (SD=16), and mean pre-transfusion hemoglobin was 7.5 g/dL (SD=0.9). No patients had MAP < 65 mm Hg (mean 89 mm Hg, SD 17) or lactate > 2.5 mmol/L (mean 1.1 mmol/L, SD 0.3). Following transfusion, ΔPPC ranged from +68% to -36% and was found to inversely correlate significantly with pre-transfusion PPC (Spearman r= -0.63, p=0.0002). Conclusions Pre-transfusion PPC may be selectively deranged in otherwise stable trauma patients. Patients with relatively altered baseline PPC tend to demonstrate improvement in perfusion following transfusion, while those with relatively normal perfusion at baseline tend to demonstrate either no change or, in fact, a decline in PPC. Bedside sublingual imaging may have the potential to detect subtle perfusion defects and ultimately inform clinical decision making with respect to transfusion. PMID:22344313

  20. Measuring red blood cell aggregation forces using double optical tweezers.

    PubMed

    Fernandes, Heloise P; Fontes, Adriana; Thomaz, André; Castro, Vagner; Cesar, Carlos L; Barjas-Castro, Maria L

    2013-04-01

    Classic immunohematology approaches, based on agglutination techniques, have been used in manual and automated immunohematology laboratory routines. Red blood cell (RBC) agglutination depends on intermolecular attractive forces (hydrophobic bonds, Van der Walls, electrostatic forces and hydrogen bonds) and repulsive interactions (zeta potential). The aim of this study was to measure the force involved in RBC aggregation using double optical tweezers, in normal serum, in the presence of erythrocyte antibodies and associated to agglutination potentiator solutions (Dextran, low ionic strength solution [LISS] and enzymes). The optical tweezers consisted of a neodymium:yattrium aluminium garnet (Nd:YAG) laser beam focused through a microscope equipped with a minicam, which registered the trapped cell image in a computer where they could be analyzed using a software. For measuring RBC aggregation, a silica bead attached to RBCs was trapped and the force needed to slide one RBC over the other, as a function of the velocities, was determined. The median of the RBC aggregation force measured in normal serum (control) was 1 × 10(-3) (0.1-2.5) poise.cm. The samples analyzed with anti-D showed 2 × 10(-3) (1.0-4.0) poise.cm (p < 0.001). RBC diluted in potentiator solutions (Dextran 0.15%, Bromelain and LISS) in the absence of erythrocyte antibodies, did not present agglutination. High adherence was observed when RBCs were treated with papain. Results are in agreement with the imunohematological routine, in which non-specific results are not observed when using LISS, Dextran and Bromelain. Nevertheless, false positive results are frequently observed in manual and automated microplate analyzer using papain enzyme. The methodology proposed is simple and could provide specific information with the possibility of meansuration regarding RBC interaction.

  1. Targeted erythropoietin selectively stimulates red blood cell expansion in vivo.

    PubMed

    Burrill, Devin R; Vernet, Andyna; Collins, James J; Silver, Pamela A; Way, Jeffrey C

    2016-05-10

    The design of cell-targeted protein therapeutics can be informed by natural protein-protein interactions that use cooperative physical contacts to achieve cell type specificity. Here we applied this approach in vivo to the anemia drug erythropoietin (EPO), to direct its activity to EPO receptors (EPO-Rs) on red blood cell (RBC) precursors and prevent interaction with EPO-Rs on nonerythroid cells, such as platelets. Our engineered EPO molecule was mutated to weaken its affinity for EPO-R, but its avidity for RBC precursors was rescued via tethering to an antibody fragment that specifically binds the human RBC marker glycophorin A (huGYPA). We systematically tested the impact of these engineering steps on in vivo markers of efficacy, side effects, and pharmacokinetics. huGYPA transgenic mice dosed with targeted EPO exhibited elevated RBC levels, with only minimal platelet effects. This in vivo selectivity depended on the weakening EPO mutation, fusion to the RBC-specific antibody, and expression of huGYPA. The terminal plasma half-life of targeted EPO was ∼28.3 h in transgenic mice vs. ∼15.5 h in nontransgenic mice, indicating that huGYPA on mature RBCs acted as a significant drug sink but did not inhibit efficacy. In a therapeutic context, our targeting approach may allow higher restorative doses of EPO without platelet-mediated side effects, and also may improve drug pharmacokinetics. These results demonstrate how rational drug design can improve in vivo specificity, with potential application to diverse protein therapeutics.

  2. Mechanism of faster NO scavenging by older stored red blood cells.

    PubMed

    Liu, Chen; Liu, Xiaohua; Janes, John; Stapley, Ryan; Patel, Rakesh P; Gladwin, Mark T; Kim-Shapiro, Daniel B

    2014-01-01

    The blood storage lesion involves morphological and biochemical changes of red blood cells (RBCs) that occur during storage. These include conversion of the biconcave disc morphology to a spherical one, decreased mean corpuscular hemoglobin concentration, varied mean corpuscular volume, reduced integrity of the erythrocyte membrane with formation of microparticles, and increased cell-free hemoglobin. We studied the extent that older stored red blood cells scavenge nitric oxide (NO) faster than fresher stored red blood cells. Using electron paramagnetic resonance spectroscopy and stopped-flow absorption spectroscopy to measure the rate of NO uptake and reaction with hemoglobin in red cells, we found that older stored red blood cells scavenge NO about 1.8 times faster than fresher ones. Based on these experimental data, we simulated NO scavenging by fresher or older stored red blood cells with a biconcave or spherical geometry, respectively, in order to explore the mechanism of NO scavenging related to changes that occur during blood storage. We found that red blood cells with a spherical geometry scavenges NO about 2 times slower than ones with a biconcave geometry, and a smaller RBC hemoglobin concentration or volume increases NO scavenging by red blood cells. Our simulations demonstrate that even the most extreme possible changes in mean corpuscular hemoglobin concentration and mean corpuscular volume that favor increased NO scavenging are insufficient to account for what is observed experimentally. Therefore, RBC membrane permeability must increase during storage and we find that the permeability is likely to increase between 5 and 70 fold. Simulations using a two-dimensional blood vessel show that even a 5-fold increase in membrane permeability to NO can reduce NO bioavailability at the smooth muscle. Transfusion of older stored blood may be harmful. Older stored red blood cells scavenge nitric oxide more than fresher cells. As stored red blood cells age

  3. The flow of red blood cells in stenosed microvessels and the influence of red blood cells on wall-bounded rolling motion of microparticles

    NASA Astrophysics Data System (ADS)

    Vahidkhah, Koohyar; Balogh, Peter; Bagchi, Prosenjit

    2015-11-01

    In the first part of this work, we consider a 3D computational study of the flow of deformable red blood cells in stenosed microvessels. We observe that the apparent viscosity of blood increases by several folds, and the rate of increase with increasing vessel diameter is also higher than that in non-stenosed vessels, implying an enhancement of the well-known Fahraeus-Lindqvist effect. The flow of the red blood cells causes time-dependent fluctuations in the blood flow rate. The RMS of the flow rate oscillations in the stenosed vessel is observed to be significantly higher than that in the non-stenosed vessel. Furthermore, several folds increase in the Eulerian velocity fluctuations and a transient flow reversal upstream the stenosed region are also observed, which would not occur in absence of the cells. In the second part, we consider the adhesive rolling motion of wall-bounded microparticles in presence of flowing red blood cells in microvessels. We observe two contradictory role of the red blood cells: On one hand, the cells facilitate the establishment of the particle-wall contact, and, thereby, initiation of adhesion. On the other hand, they augment the rolling velocity of the particles. Implications of these results on the optimal design of drug carriers are discussed.

  4. Effect of aggregation and shear rate on the dispersion of red blood cells flowing in venules.

    PubMed

    Bishop, Jeffrey J; Popel, Aleksander S; Intaglietta, Marcos; Johnson, Paul C

    2002-11-01

    Previous in vitro studies of blood flow in small glass tubes have shown that red blood cells exhibit significant erratic deviations in the radial position in the laminar flow regime. The purpose of the present study was to assess the magnitude of this variability and that of velocity in vivo and the effect of red blood cell aggregation and shear rate upon them. With the use of a gated image intensifier and fluorescently labeled red blood cells in tracer quantities, we obtained multiple measurements of red blood cell radial and longitudinal positions at time intervals as short as 5 ms within single venous microvessels (diameter range 45-75 microm) of the rat spinotrapezius muscle. For nonaggregating red blood cells in the velocity range of 0.3-14 mm/s, the mean coefficient of variation of velocity was 16.9 +/- 10.5% and the SD of the radial position was 1.98 +/- 0.98 microm. Both quantities were inversely related to shear rate, and the former was significantly lowered on induction of red blood cell aggregation by the addition of Dextran 500 to the blood. The shear-induced random movements observed in this study may increase the radial transport of particles and solutes within the bloodstream by orders of magnitude.

  5. The energy-less red blood cell is lost: erythrocyte enzyme abnormalities of glycolysis.

    PubMed

    van Wijk, Richard; van Solinge, Wouter W

    2005-12-15

    The red blood cell depends solely on the anaerobic conversion of glucose by the Embden-Meyerhof pathway for the generation and storage of high-energy phosphates, which is necessary for the maintenance of a number of vital functions. Many red blood cell enzymopathies have been described that disturb the erythrocyte's integrity, shorten its cellular survival, and result in hemolytic anemia. By far the majority of these enzymopathies are hereditary in nature. In this review, we summarize the current knowledge regarding the genetic, biochemical, and structural features of clinically relevant red blood cell enzymopathies involved in the Embden-Meyerhof pathway and the Rapoport-Luebering shunt.

  6. Theoretical models for near forward light scattering by a Plasmodium falciparum infected red blood cell

    NASA Astrophysics Data System (ADS)

    Sharma, S. K.

    2012-12-01

    A number of experimental elastic light scattering studies have been performed in the past few years with the aim of developing automated in vivo tools for differentiating a healthy red blood cell from a Plasmodium falciparum infected cell. This paper examines some theoretical aspects of the problem. An attempt has been made to simulate the scattering patterns of healthy as well as infected individual red blood cells. Two models, namely, a homogeneous sphere model and a coated sphere model have been considered. The scattering patterns predicted by these models are examined. A possible method for discriminating infected red blood cells from healthy ones has been suggested.

  7. Washing stored red blood cells in an albumin solution improves their morphological and hemorheological properties

    PubMed Central

    Reinhart, Walter H.; Piety, Nathaniel Z.; Deuel, Jeremy W.; Makhro, Asya; Schulzki, Thomas; Bogdanov, Nikolay; Goede, Jeroen S.; Bogdanova, Anna; Abidi, Rajaa; Shevkoplyas, Sergey S.

    2015-01-01

    BACKGROUND Prolonged storage of red blood cells leads to storage lesions, which may impair clinical outcomes after transfusion. A hallmark of storage lesions is progressive echinocytic shape transformation, which can be partially reversed by washing in albumin solutions. Here we have investigated the impact of this shape recovery on biorheological parameters. METHODS Red blood cells stored hypothermically for 6–7 weeks were washed in a 1% human serum albumin solution. Red cell deformability was measured with osmotic gradient ektacytometry. The viscosity of red cell suspensions were measured with a Couette-type viscometer. The flow behaviour of red cells suspended at 40% hematocrit was tested with an artificial microvascular network. RESULTS Washing in 1% albumin reduced higher degrees of echinocytes and increased the frequency of discocytes, thereby shifting the morphological index towards discocytosis. Washing also reduced red cell swelling. This shape recovery was not seen after washing in saline, buffer or plasma. Red cell shape normalisation did not improve cell deformability measured by ektacytometry, but it tended to decrease suspension viscosities at low shear rates and improved the perfusion of an artificial microvascular network. CONCLUSIONS Washing of stored red blood cells in a 1% human serum albumin solution specifically reduces echinocytosis, and this shape recovery has a beneficial effect on microvascular perfusion in vitro. Washing in 1% albumin may represent a new approach to improving the quality of stored red cells, and thus potentially reducing the likelihood of adverse clinical outcomes associated with transfusion of blood stored for longer periods of time. PMID:25752902

  8. Endothelial Lu/BCAM glycoproteins are novel ligands for red blood cell alpha4beta1 integrin: role in adhesion of sickle red blood cells to endothelial cells.

    PubMed

    El Nemer, Wassim; Wautier, Marie-Paule; Rahuel, Cécile; Gane, Pierre; Hermand, Patricia; Galactéros, Frédéric; Wautier, Jean-Luc; Cartron, Jean-Pierre; Colin, Yves; Le Van Kim, Caroline

    2007-04-15

    The Lutheran (Lu) blood group and basal cell adhesion molecule (BCAM) antigens are both carried by 2 glycoprotein isoforms of the immunoglobulin superfamily representing receptors for the laminin alpha(5) chain. In addition to red blood cells, Lu/BCAM proteins are highly expressed in endothelial cells. Abnormal adhesion of red blood cells to the endothelium could potentially contribute to the vaso-occlusive episodes in sickle cell disease. Considering the presence of integrin consensus-binding sites in Lu/BCAM proteins, we investigated their potential interaction with integrin alpha(4)beta(1), the unique integrin expressed on immature circulating sickle red cells. Using cell adhesion assays under static and flow conditions, we demonstrated that integrin alpha(4)beta(1) expressed on transfected cells bound to chimeric Lu-Fc protein. We showed that epinephrine-stimulated sickle cells, but not control red cells, adhered to Lu-Fc via integrin alpha(4)beta(1) under flow conditions. Antibody-mediated activation of integrin alpha(4)beta(1) induced adhesion of sickle red cells to primary human umbilical vein endothelial cells; this adhesion was inhibited by soluble Lu-Fc and vascular cell adhesion molecule-1 (VCAM-1)-Fc proteins. This novel interaction between integrin alpha(4)beta(1) in sickle red cells and endothelial Lu/BCAM proteins could participate in sickle cell adhesion to endothelium and potentially play a role in vaso-occlusive episodes.

  9. Cocaine induces a reversible stomatocytosis of red blood cells and increases blood viscosity.

    PubMed

    Cagienard, F; Schulzki, T; Furlong, P; Reinhart, W H

    2013-01-01

    Severe side effects of cocaine consumption are vasoocclusive events such as myocardial infarction and stroke. We have hypothesized that cocaine could affect red blood cells (RBCs) and alter the rheological behaviour of blood. Heparinized blood from healthy volunteers was incubated with a final hematocrit of 45% with increasing cocaine concentrations: 0, 10, 100, 1000, and 10'000 μmol/L plasma. Time dependence of the shape change was tested in phosphate buffered saline containing cocaine. RBCs were fixed in 1% glutaraldehyde for morphological analysis. Blood viscosity was measured with a Couette Viscometer (Contraves LS 30) at 37°C and a shear rate of 69.5 s⁻¹. RBC aggregation was assessed with a Myrenne aggregometer. Cocaine induced a dose-dependent stomatocytic shape transformation of RBCs, which was more pronounced in buffer than in plasma (plasma protein binding of the drug). Stomatocytosis occurs when a drug intercalates preferentially in the inner half of the membrane lipid bilayer. It was a time-dependent process with two components, an almost instant shape change occurring within 1 s, followed by a gradual further shape change during 10 min. Stomatocytosis was reversible by resuspension of the RBCs in cocaine-free buffer. This stomatocytic shape change increased whole blood viscosity at high shear rate from 5.69±0.31 mPa.s to 6.39±0.34 mPa.s for control and 10'000 μmol/L cocaine, respectively (p<0.01). RBC aggregation was not affected by the shape change. These effects occurred at a cocaine concentration, which is several-fold above those measured in vivo. Therefore, it is unlikely that hemorheological factors are involved in vascular events after cocaine consumption.

  10. Multiscale Modeling of Red Blood Cell Mechanics and Blood Flow in Malaria

    PubMed Central

    Fedosov, Dmitry A.; Lei, Huan; Caswell, Bruce; Suresh, Subra; Karniadakis, George E.

    2011-01-01

    Red blood cells (RBCs) infected by a Plasmodium parasite in malaria may lose their membrane deformability with a relative membrane stiffening more than ten-fold in comparison with healthy RBCs leading to potential capillary occlusions. Moreover, infected RBCs are able to adhere to other healthy and parasitized cells and to the vascular endothelium resulting in a substantial disruption of normal blood circulation. In the present work, we simulate infected RBCs in malaria using a multiscale RBC model based on the dissipative particle dynamics method, coupling scales at the sub-cellular level with scales at the vessel size. Our objective is to conduct a full validation of the RBC model with a diverse set of experimental data, including temperature dependence, and to identify the limitations of this purely mechanistic model. The simulated elastic deformations of parasitized RBCs match those obtained in optical-tweezers experiments for different stages of intra-erythrocytic parasite development. The rheological properties of RBCs in malaria are compared with those obtained by optical magnetic twisting cytometry and by monitoring membrane fluctuations at room, physiological, and febrile temperatures. We also study the dynamics of infected RBCs in Poiseuille flow in comparison with healthy cells and present validated bulk viscosity predictions of malaria-infected blood for a wide range of parasitemia levels (percentage of infected RBCs with respect to the total number of cells in a unit volume). PMID:22144878

  11. Quantitative photoacoustic assessment of red blood cell aggregation under pulsatile blood flow: experimental and theoretical approaches

    NASA Astrophysics Data System (ADS)

    Bok, Tae-Hoon; Hysi, Eno; Kolios, Michael C.

    2017-03-01

    In the present paper, the optical wavelength dependence on the photoacoustic (PA) assessment of the pulsatile blood flow was investigated by means of the experimental and theoretical approaches analyzing PA radiofrequency spectral parameters such as the spectral slope (SS) and mid-band fit (MBF). For the experimental approach, the pulsatile flow of human whole blood at 60 bpm was imaged using the VevoLAZR system (40-MHz-linear-array probe, 700-900 nm illuminations). For the theoretical approach, a Monte Carlo simulation for the light transmit into a layered tissue phantom and a Green's function based method for the PA wave generation was implemented for illumination wavelengths of 700, 750, 800, 850 and 900 nm. The SS and MBF for the experimental results were compared to theoretical ones as a function of the illumination wavelength. The MBF increased with the optical wavelength in both theory and experiments. This was expected because the MBF is representative of the PA magnitude, and the PA signal from red blood cell (RBC) is dependent on the molar extinction coefficient of oxyhemoglobin. On the other hand, the SS decreased with the wavelength, even though the RBC size (absorber size which is related to the SS) cannot depend on the illumination wavelength. This conflicting result can be interpreted by means of the changes of the fluence pattern for different illumination wavelengths. The SS decrease with the increasing illumination wavelength should be further investigated.

  12. Spring-network-based model of a red blood cell for simulating mesoscopic blood flow.

    PubMed

    Nakamura, Masanori; Bessho, Sadao; Wada, Shigeo

    2013-01-01

    We developed a mechanical model of a red blood cell (RBC) that is capable of expressing its characteristic behaviors in shear flows. The RBC was modeled as a closed shell membrane consisting of spring networks in the framework of the energy minimum concept. The fluid forces acting on RBCs were modeled from Newton's viscosity law and the conservation of momentum. In a steady shear flow, the RBC model exhibited various behaviors, depending on the shear rate; it tumbled, tank-treaded, or both. The transition from tumbling to tank-treading occurred at a shear rate of 20 s( - 1). The simulation of an RBC in steady and unsteady parallel shear flows (Couette flows) showed that the deformation parameters of the RBC were consistent with experimental results. The RBC in Poiseuille flow migrated radially towards the central axis of the flow channel. Axial migration became faster with an increase in the viscosity of the media, qualitatively consistent with experimental results. These results demonstrate that the proposed model satisfies the essential conditions for simulating RBC behavior in blood flow. Finally, a large-scale RBC flow simulation was implemented to show the capability of the proposed model for analyzing the mesoscopic nature of blood flow.

  13. Multiscale modeling of red blood cell mechanics and blood flow in malaria.

    PubMed

    Fedosov, Dmitry A; Lei, Huan; Caswell, Bruce; Suresh, Subra; Karniadakis, George E

    2011-12-01

    Red blood cells (RBCs) infected by a Plasmodium parasite in malaria may lose their membrane deformability with a relative membrane stiffening more than ten-fold in comparison with healthy RBCs leading to potential capillary occlusions. Moreover, infected RBCs are able to adhere to other healthy and parasitized cells and to the vascular endothelium resulting in a substantial disruption of normal blood circulation. In the present work, we simulate infected RBCs in malaria using a multiscale RBC model based on the dissipative particle dynamics method, coupling scales at the sub-cellular level with scales at the vessel size. Our objective is to conduct a full validation of the RBC model with a diverse set of experimental data, including temperature dependence, and to identify the limitations of this purely mechanistic model. The simulated elastic deformations of parasitized RBCs match those obtained in optical-tweezers experiments for different stages of intra-erythrocytic parasite development. The rheological properties of RBCs in malaria are compared with those obtained by optical magnetic twisting cytometry and by monitoring membrane fluctuations at room, physiological, and febrile temperatures. We also study the dynamics of infected RBCs in Poiseuille flow in comparison with healthy cells and present validated bulk viscosity predictions of malaria-infected blood for a wide range of parasitemia levels (percentage of infected RBCs with respect to the total number of cells in a unit volume).

  14. Application of the ADVIA cerebrospinal fluid assay to count residual red blood cells in blood components.

    PubMed

    Culibrk, B; Stone, E; Levin, E; Weiss, S; Serrano, K; Devine, D V

    2012-10-01

    There is no automated, accurate assay for the enumeration of residual red blood cells (rRBCs) in non-RBC components for transfusion, despite the potential risk of allo-immunization when mismatched components are transfused. The automated ADVIA 120 cerebrospinal fluid (CSF) assay, which is approved to count RBCs and WBCs in CSF samples, was optimized and tested to measure rRBC in platelet concentrate (PC) and plasma components. Sample dilution, incubation time and reagent volume were optimized for use with non-RBC blood products. The assay was linear (R(2) = 0·99), even at low rRBCs counts. Intra- and inter-assay variation gave coefficients of variance (CV) between 2·2 and 9·4% and 2·6 and 14·9%, respectively, depending on rRBC levels. Good correlation (r = 0·995) was found between the automated assay and manual counting, which is considered the gold standard. Using the automated assay, the range of rRBCs (count/unit) in buffy-coat platelet concentrate (PCs) was 27-5505 × 10(6) and in apheresis PCs was 1-361 × 10(6). The ADVIA CSF assay is a sensitive, precise and accurate means to assess rRBC counts in non-RBC components. © 2012 The Author(s). Vox Sanguinis © 2012 International Society of Blood Transfusion.

  15. Cinnamomum zeylanicum extract on the radiolabelling of blood constituents and the morphometry of red blood cells: in vitro assay.

    PubMed

    Benarroz, M O; Fonseca, A S; Rocha, G S; Frydman, J N G; Rocha, V C; Pereira, M O; Bernardo-Filho, M

    2008-02-01

    Effects of Cinnamomum zeylanicum (cinnamon) on the labelling of blood constituents with technetium-99m(99mTc) and on the morphology of red blood cells were studied. Blood samples from Wistar rats were incubated with cinnamon extract for 1 hour or with 0.9% NaCl, as control. Labelling of blood constituents with 99mTc was performed. Plasma (P) and blood cells (BC), soluble (SF-P and SF-BC) and insoluble (IF-P and IF-BC) fractions were separated. The radioactivity in each fraction was counted and the percentage of radioactivity incorporated (%ATI) was calculated. Blood smears were prepared, fixed, stained and the qualitative and quantitative morphological analysis of the red blood cells was evaluated. The data showed that the cinnamon extract decreased significantly (p<0.05) the %ATI on BC, IF-P and IF-BC. No modifications were verified on shape of red blood cells. Cinnamon extracts could alter the labelling of blood constituents with 99mTc, and although our results were obtained with animals, precaution is suggested in interpretations of nuclear medicine examinations involving the labelling of blood constituents in patients who are using cinnamon.

  16. Linoleic acid induces red blood cells and hemoglobin damage via oxidative mechanism.

    PubMed

    Yuan, Tao; Fan, Wen-Bin; Cong, Yu; Xu, Hai-Dong; Li, Cheng-Jun; Meng, Jia; Bao, Ni-Rong; Zhao, Jian-Ning

    2015-01-01

    Hidden blood loss typically occurs following total hip arthroplasty (THA) and total knee arthroplasty (TKA) and is thought to be related to free fatty acid (FFA). To study the effect of linoleic acid on red blood cells and to examine the pathogenesis of hidden blood loss in vivo, we generated an animal model by injecting linoleic acid into the tail veins of rats. We collected blood samples and determined red blood cell count (RBC) and levels of hemoglobin (Hb), as well as the oxidation and reducing agents in the blood, including glutathione peroxidase (GSH-PX), total superoxide dismutase (T-SOD), hydrogen peroxide (H2O2), and ferryl hemoglobin (Fe4+=O2-), which is generated by the oxidation of Hb. Hidden blood loss occurred when linoleic acid was administered at a concentration of 60 mmol/L; RBC and Hb levels were significantly reduced by 24 h post-injection. This was followed by erythrocyte deformation, reduced activity of GSH-PX and T-SOD, and decreased levels of H2O2. This was accompanied by an increase in ferryl species, which likely contributes to oxidative stress in vivo. Our findings suggest that linoleic acid enhances acute red blood cell injury. Hb and RBC began to increase by 72 h, potentially resulting from linoleic acid metabolism. Thus, elevated levels of linoleic acid in the blood cause acute oxidative damage to red blood cells, eventually leading to partial acute anemia. These findings highlight the pathophysiology underlying hidden blood loss.

  17. Red Blood Cell Hematocrit Influences Platelet Adhesion Rate in a Microchannel

    NASA Astrophysics Data System (ADS)

    Spann, Andrew; Campbell, James; Fitzgibbon, Sean; Rodriguez, Armando; Shaqfeh, Eric

    2014-11-01

    The creation of a blood clot to stop bleeding involves platelets forming a plug at the site of injury. Red blood cells indirectly play a role in ensuring that the distribution of platelets across the height of the channel is not uniform - the contrast in deformability and size between platelets and red blood cells allows the platelets to preferentially marginate close to the walls. We perform 3D boundary integral simulations of a suspension of platelets and red blood cells in a periodic channel with a model that allows for platelet binding at the walls. The relative rate of platelet activity with varying hematocrit (volume fraction of red blood cells) is compared to experiments in which red blood cells and platelets flow through a channel coated with von Willebrand factor. In the simulations as well as the experiments, a decrease in hematocrit of red blood cells is found to reduce the rate at which platelets adhere to the channel wall in a manner that is both qualitatively and quantitatively similar. We conclude with a discussion of the tumbling and wobbling motions of platelets in 3D leading up to the time at which the platelets bind to the wall. Funded by Stanford Army High Performance Computing Research Center, experiments by US Army Institute of Surgical Research.

  18. [Preparation of transfusable human universal red blood cell with recombinant alpha-galactosidase].

    PubMed

    Gong, Feng; Lü, Qiu-Shuang; You, Ying; Gao, Hong-Wei; Bao, Guo-Qiang; Gao, Xin; Li, Su-Bo; Li, Li-Li; Wang, Ying-Li; Tian, Shu-Guang; Zhang, Zhi-Xin; Zhang, Ping; Zhang, Yang-Pei

    2005-04-01

    In order to meet the demand for safe transfusion in special conditions and to utilize the donated blood supply efficiently, technology has been developed to convert erythrocytes from type A, B, or AB to "universal donor" blood. Conversion of blood type B to O was performed by means of recombinant alpha-galactosidase digestion. The results showed that blood type B to O was converted successfully, 1 transfusion unit of red cells of group B (100 ml totally) could converted to universal blood cells in the optimal conditions including pH 5.6, 26 degrees C, 2 hours, obturation and sterilization. It is concluded that the universal red blood cells converted from group B to group O are conformed to demand of identification rules of biological products, no harmful effects of alpha-galactosidase on cell structure and function are observed. The converted red cells can stored in 4 degrees C for 21 days.

  19. Polymer/hemoglobin assemblies: biodegradable oxygen carriers for artificial red blood cells.

    PubMed

    Li, Taihang; Jing, Xiabin; Huang, Yubin

    2011-07-07

    In routine clinical procedures, blood transfusion is now suffering from the defects of the blood products, like cross-matching, short storage time and virus infection. Various blood substitutes have been designed by researchers through continual efforts. With recent progress in nanotechnology, new types of artificial red blood cells with cellular structure are available. This article aims to describe some artificial red blood cells which encapsulate or conjugate hemoglobin molecules through various approaches, especially the nanoscale self-assembly technique, to mitigate the adverse effects of free hemoglobin molecules. These types of artificial red blood cell systems, which make use of biodegradable polymers as matrix materials, show advantages over the traditional types. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Lattice Boltzmann Simulation of Healthy and Defective Red Blood Cell Settling in Blood Plasma.

    PubMed

    Hashemi, Z; Rahnama, M; Jafari, S

    2016-05-01

    In this paper, an attempt has been made to study sedimentation of a red blood cell (RBC) in a plasma-filled tube numerically. Such behaviors are studied for a healthy and a defective cell which might be created due to human diseases, such as diabetes, sickle-cell anemia, and hereditary spherocytosis. Flow-induced deformation of RBC is obtained using finite-element method (FEM), while flow and fluid-membrane interaction are handled using lattice Boltzmann (LB) and immersed boundary methods (IBMs), respectively. The effects of RBC properties as well as its geometry and orientation on its sedimentation rate are investigated and discussed. The results show that decreasing frontal area of an RBC and/or increasing tube diameter results in a faster settling. Comparison of healthy and diabetic cells reveals that less cell deformability leads to slower settling. The simulation results show that the sicklelike and spherelike RBCs have lower settling velocity as compared with a biconcave discoid cell.

  1. Research opportunities in loss of red blood cell mass in space flight

    NASA Technical Reports Server (NTRS)

    Talbot, J. M.; Fisher, K. D.

    1985-01-01

    Decreases of red blood cell mass and plasma volume have been observed consistently following manned space flights. Losses of red cell mass by United States astronauts have averaged 10 to 15% (range: 2 to 21%). Based on postflight estimates of total hemoglobin, Soviet cosmonauts engaged in space missions lasting from 1 to 7 months have exhibited somewhat greater losses. Restoration of red cell mass requires from 4 to 6 weeks following return to Earth, regardless of the duration of space flight.

  2. Temporal sequence of major biochemical events during Blood Bank storage of packed red blood cells

    PubMed Central

    Karon, Brad S.; van Buskirk, Camille M.; Jaben, Elizabeth A.; Hoyer, James D.; Thomas, David D.

    2012-01-01

    Background. We used sensitive spectroscopic techniques to measure changes in Band 3 oligomeric state during storage of packed red blood cells (RBC); these changes were compared to metabolic changes, RBC morphology, cholesterol and membrane protein loss, phospholipid reorganisation of the RBC membrane, and peroxidation of membrane lipid. The aim of the study was to temporally sequence major biochemical events occurring during cold storage, in order to determine which changes may underlie the structural defects in stored RBC. Materials and methods. Fifteen RBC units were collected from normal volunteers and stored under standard blood bank conditions; both metabolic changes and lipid parameters were measured by multiple novel assays including a new mass spectrometric measurement of isoprostane (lipid peroxidation) and flow cytometric assessment of CD47 expression. Band 3 oligomeric state was assessed by time-resolved phosphorescence anisotropy, and RBC morphology by microscopy of glutaraldehyde-fixed RBC. Results. Extracellular pH decreased and extracellular potassium increased rapidly during cold storage. Band 3 on the RBC membrane aggregated into large oligomers early in the storage period and coincident with changes in RBC morphology. Membrane lipid changes, including loss of unesterified cholesterol, lipid peroxidation and expression of CD47, also changed early during the storage period. In contrast loss of acetylcholinesterase activity and haemolysis of RBC occurred late during storage. Discussion. Our results demonstrate that changes in the macromolecular organisation of membrane proteins on the RBC occur early in storage and suggest that lipid peroxidation and/or oxidative damage to the membrane are responsible for irreversible morphological changes and loss of function during red cell storage. PMID:22507860

  3. Multi-omics Evidence for Inheritance of Energy Pathways in Red Blood Cells.

    PubMed

    Weisenhorn, Erin M M; van T Erve, Thomas J; Riley, Nicholas M; Hess, John R; Raife, Thomas J; Coon, Joshua J

    2016-12-01

    Each year over 90 million units of blood are transfused worldwide. Our dependence on this blood supply mandates optimized blood management and storage. During storage, red blood cells undergo degenerative processes resulting in altered metabolic characteristics which may make blood less viable for transfusion. However, not all stored blood spoils at the same rate, a difference that has been attributed to variable rates of energy usage and metabolism in red blood cells. Specific metabolite abundances are heritable traits; however, the link between heritability of energy metabolism and red blood cell storage profiles is unclear. Herein we performed a comprehensive metabolomics and proteomics study of red blood cells from 18 mono- and di-zygotic twin pairs to measure heritability and identify correlations with ATP and other molecular indices of energy metabolism. Without using affinity-based hemoglobin depletion, our work afforded the deepest multi-omic characterization of red blood cell membranes to date (1280 membrane proteins and 330 metabolites), with 119 membrane protein and 148 metabolite concentrations found to be over 30% heritable. We demonstrate a high degree of heritability in the concentration of energy metabolism metabolites, especially glycolytic metabolites. In addition to being heritable, proteins and metabolites involved in glycolysis and redox metabolism are highly correlated, suggesting that crucial energy metabolism pathways are inherited en bloc at distinct levels. We conclude that individuals can inherit a phenotype composed of higher or lower concentrations of these proteins together. This can result in vastly different red blood cells storage profiles which may need to be considered to develop precise and individualized storage options. Beyond guiding proper blood storage, this intimate link in heritability between energy and redox metabolism pathways may someday prove useful in determining the predisposition of an individual toward metabolic

  4. Recurrent thymoma with stiff-person syndrome and pure red blood cell aplasia.

    PubMed

    Kobayashi, Rei; Kaji, Masahiro; Horiuchi, Sho; Miyahara, Naofumi; Hino, Yumi; Suemasu, Keiichi

    2014-05-01

    Stiff-person syndrome (formerly known as stiff-man syndrome) is a very rare autoimmune and neurogenic disorder, thought to present as a paraneoplastic variant in association with thymoma. Pure red blood cell aplasia is also a paraneoplastic disorder associated with thymoma. Although separate cases of stiff-person syndrome and pure red blood cell aplasia have been reported, we describe here what is to our knowledge the first case of recurrent thymoma with both stiff-person syndrome and pure red blood cell aplasia. We describe the successful treatment of the neurogenic symptoms of stiff-person syndrome and the progressive anemia associated with pure red blood cell aplasia by tumor excision.

  5. Numerical analysis on cell-cell interaction of red blood cells during sedimentation

    NASA Astrophysics Data System (ADS)

    Shi, Xing

    2017-07-01

    The long-range hydrodynamic interaction among red blood cells plays an important role on the macroscopic behaviors, however, the molecular interaction at such scale is much weaker. In this paper, the sedimentations under external body force of two red blood cells are numerical simulated to investigate the hydrodynamic interaction between cells. The flow is solved by lattice Boltzmann method and the membrane of red blood cell is model by the spring model where the fluid-membrane interaction is coupled by fictitious domain method. It is found that the cells have the tendency to aggregate and may be aligned in a line along the sediment direction. Compared to the properties of a single cell under the same conditions, the sediment velocity of red blood cell group is larger; the leading cell deforms less and the following cell endures larger deformation.

  6. Safe extension of red blood cell storage life at 4{degree}C

    SciTech Connect

    Bitensky, M.; Yoshida, Tatsuro

    1996-04-01

    The project sought to develop methods to extend the storage life of red blood cells. Extended storage would allow donor to self or autologous transfusion, expand and stabilize the blood supply, reduce the cost of medical care and eliminate the risk of transfusion related infections, including a spectrum of hepatitides (A, B and C) and HIV. The putative cause of red blood cell spoilage at 4 C has been identified as oxidative membrane damage resulting from deoxyhemoglobin and its denaturation products including hemichrome, hemin and Fe{sup 3+}. Trials with carbon monoxide, which is a stabilizer of hemoglobin, have produced striking improvement of red blood cell diagnostics for cells stored at 4 C. Carbonmonoxy hemoglobin is readily converted to oxyhemoglobin by light in the presence of oxygen. These findings have generated a working model and an approach to identify the best protocols for optimal red cell storage and hemoglobin regeneration.

  7. The effect of cyanide on the uptake of gold by red blood cells.

    PubMed

    Graham, G G; Haavisto, T M; Jones, H M; Champion, G D

    1984-04-15

    Cyanide markedly increased the rate of uptake of gold by red blood cells when incubated with sodium aurothiomalate, a polymeric gold complex. Thiocyanate had no significant effect on gold uptake. The effect of cyanide was demonstrated to be due to the conversion of aurothiomalate to the complexion, aurocyanide, which is rapidly taken up by red blood cells. At a low ratio (1:20) of cyanide to aurothiomalate, cyanide appeared to act as a shuttle to carry gold into red blood cells. Tobacco smoking is known to increase the concentrations of gold in red blood cells in patients treated with aurothiomalate. The present data indicate that this effect of smoking is most likely due to cyanide inhaled in tobacco smoke and not to thiocyanate, a circulating metabolite of cyanide. An effect of cyanide on the uptake of polymeric gold complexes to target cells such as polymorphonuclear leukocytes and monocytes is suggested.

  8. A new dihydrochalcone from dragon's blood, red resin of Dracaena cochinchinensis.

    PubMed

    Yong, Ke-Lan; Lv, Jing-Ci; Zhang, Tian-Bao; Xu, Lu-Rong; Chen, Xu

    2008-12-01

    A new dihydrochalcone, 4'-hydroxy-4,2'-dimethoxy-dihydrochalcone, was isolated from Chinese dragon's blood, the red resin of Dracaena cochinchinensis. Its structure was established by spectrum analysis.

  9. Visualization of cutaneous hemangioma with Tc-99m tagged red blood cells

    SciTech Connect

    Gordon, L.; Vujic, I.; Spicer, K.M.

    1981-10-01

    Scintigraphy with Tc-99m labeled red blood cells (RBCs) was used to evaluate a patient with a large cutaneous hemangioma. The usefulness of this procedure when combined with arteriography is discussed.

  10. Evaluation of a volumetric intravenous fluid infusion pump for transfusion of blood components containing red cells.

    PubMed

    Thompson, H W; Lasky, L C; Polesky, H F

    1986-01-01

    A method was devised to evaluate the suitability of an infusion pump for transfusing components containing red cells. With simulated transfusions of units of whole blood tested before or after the expiration date there was no increase in the plasma hemoglobin level in pumped blood compared with blood that was put through a standard blood transfusion set. With outdated units of red cells there was an increased level of plasma hemoglobin after pumping. The increases were greatest at maximum pump rates, but were not statistically or clinically significant. The authors' evaluation indicates that this pump causes minimal damage to the red cells, although care should be exercised when rapidly transfusing red cells with high hematocrit values.

  11. Role molecular signaling pathways in changes of red blood cell deformability.

    PubMed

    Muravyov, Alexei V; Tikhomirova, Irina A

    2013-01-01

    This study was designed to investigate the dependency of the red blood cell deformability upon activation of extra- and intracellular signaling pathways. Exposures of red blood cells (RBCs) to catecholamines and to insulin led to positive change in the RBC deformability. When forskolin, a stimulator of adenylyl cyclase (AC), was added to RBC suspension, the RBC deformability was increased. Somewhat more significant deformability rise appeared after RBC incubation with dB-AMP. The inhibitors of phosphodiesterase (PDE) activity increased red cell deformability. These results revealed a considerable role of the AC-cAMP signaling system in the regulation of red blood cell deformability. The rise of the red blood cell Ca(2+) influx, stimulated by mechanical loading or A23187 was accompanied by a marked lowering of RBC deformability. At the same time blocking of Ca(2+) entry into RBC by verapamil or Ca(2+) chelating by EGTA led to significant deformability rise. The comparison of the effect of the different protein kinases on the red blood cell deformability showed that it was altered more considerable under PKA activation by forskolin or dB-cAMP than by other protein kinases. There was a lesser but quite statistically significant effect of tyrosine protein kinase (TPK) on RBC microrheology. Whereas the microrheological effect of PKC was not so considerable. The problem of the short-term regulation of red blood cell microrheology is examined. The latter includes: the modes of activation of extra- and intracellular molecular signaling pathways, ligand - receptor interaction, second messengers, membrane protein phosphorylation. On the whole the total data clearly show that the red cell deformability changes are connected with activation of different extra - and intracellular signaling pathways. It seems reasonable to suppose that red blood cell deformability changes were mainly associated with activation of the AC-cAMP-PKA pathway, and with decrease of Ca(2+) entry into

  12. Hydrogen ion dynamics in human red blood cells.

    PubMed

    Swietach, Pawel; Tiffert, Teresa; Mauritz, Jakob M A; Seear, Rachel; Esposito, Alessandro; Kaminski, Clemens F; Lew, Virgilio L; Vaughan-Jones, Richard D

    2010-12-15

    Our understanding of pH regulation within red blood cells (RBCs) has been inferred mainly from indirect experiments rather than from in situ measurements of intracellular pH (pH(i)). The present work shows that carboxy-SNARF-1, a pH fluorophore, when used with confocal imaging or flow cytometry, reliably reports pH(i) in individual, human RBCs, provided intracellular fluorescence is calibrated using a 'null-point' procedure. Mean pH(i) was 7.25 in CO(2)/HCO(3)(-)-buffered medium and 7.15 in Hepes-buffered medium, and varied linearly with extracellular pH (slope of 0.77). Intrinsic (non-CO(2)/HCO(3)(-)-dependent) buffering power, estimated in the intact cell (85 mmol (l cell)(-1) (pH unit)(-1) at resting pH(i)), was somewhat higher than previous estimates from cell lysates (50-70 mmol (l cell)(-1) (pH unit)(-1)). Acute displacement of pH(i) (superfusion of weak acids/bases) triggered rapid pH(i) recovery. This was mediated via membrane Cl(-)/HCO(3)(-) exchange (the AE1 gene product), irrespective of whether recovery was from an intracellular acid or base load, and with no evident contribution from other transporters such as Na(+)/H(+) exchange. H(+)-equivalent flux through AE1 was a linear function of [H(+)](i) and reversed at resting pH(i), indicating that its activity is not allosterically regulated by pH(i), in contrast to other AE isoforms. By simultaneously monitoring pH(i) and markers of cell volume, a functional link between membrane ion transport, volume and pH(i) was demonstrated. RBC pH(i) is therefore tightly regulated via AE1 activity, but modulated during changes of cell volume. A comparable volume-pH(i) link may also be important in other cell types expressing anion exchangers. Direct measurement of pH(i) should be useful in future investigations of RBC physiology and pathology.

  13. [Trehalose loading red blood cells and freeze-drying preservation].

    PubMed

    Chen, Yan; Lu, Zhi-Gang; Han, Ying

    2006-06-01

    This study was aimed to investigate the feasibility of cryopreserving red blood cells (RBCs) by loading with trehalose and to evaluate the effect of trehalose on lyophilized RBCs. Based on the thermal properties of RBC plasma membrane, the RBCs were incubated in 0.8 mol/L trehalose solution at 37 degrees C for 7 hours, and RBCs incubated in phosphate-buffered saline were used as control. The morphology of RBCs was observed by light and scanning electron microscopy, the hemolysis rate of loaded RBCs was detected by using cyanohemoglobin kit, the intracellular trehalose levels were assayed by sulfate anthrone method, the intracellular ATP and 2, 3-DPG levels were determined by bioluminescence assay and 2, 3-DPG kit respectively, meanwhile the deformation and osmotic fragility of RBCs were measured. The results showed that the intracellular trehalose concentration was 36.56 +/- 7.95 mmol/L, the electronical microscopic images of trehalose-loaded RBCs showed the membrane integrity, the hemolysis rate in trehalose-loaded RBCs was 15.663 +/- 3.848%, while hemolysis rate in controlled RBC was 5.03 +/- 1.85% (P < 0.05). Maximum index of deformation in trehalose-loaded RBC was 0.0289 +/- 0.00738, while maximum index of deformation in control group was 0.1200 +/- 0.0121 (P < 0.05), The level of ATP in trehalose-loaded RBC was 2.67 +/- 0.54 micromol/gHb, while the level of ATP in control group was 5.22 +/- 1.10 micromol/gHb (P > 0.05). Osmotic fragility data showed that trehalose exerted osmotic protection on RBC. During loading period the level of 2, 3-DPG in trehalose-loaded RBC was maintained close to the level in control. When trehalose-loaded RBCs were lyophilized and rehydrated, the recovery rate of hemoglobin was about 46.44 +/- 4.14% and that in control was 8.33 +/- 2.34% (P < 0.001). The recovery rate of hemoglobin of trehalose-loaded RBC was higher than that of control. It is concluded that trehalose can be integrated in the membrane of RBC in lyophilization state

  14. Characterization of Microvesicles Released from Human Red Blood Cells.

    PubMed

    Nguyen, Duc Bach; Ly, Thi Bich Thuy; Wesseling, Mauro Carlos; Hittinger, Marius; Torge, Afra; Devitt, Andrew; Perrie, Yvonne; Bernhardt, Ingolf

    2016-01-01

    Extracellular vesicles (EVs) are spherical fragments of cell membrane released from various cell types under physiological as well as pathological conditions. Based on their size and origin, EVs are classified as exosome, microvesicles (MVs) and apoptotic bodies. Recently, the release of MVs from human red blood cells (RBCs) under different conditions has been reported. MVs are released by outward budding and fission of the plasma membrane. However, the outward budding process itself, the release of MVs and the physical properties of these MVs have not been well investigated. The aim of this study is to investigate the formation process, isolation and characterization of MVs released from RBCs under conditions of stimulating Ca2+ uptake and activation of protein kinase C. Experiments were performed based on single cell fluorescence imaging, fluorescence activated cell sorter/flow cytometer (FACS), scanning electron microscopy (SEM), atomic force microscopy (AFM) and dynamic light scattering (DLS). The released MVs were collected by differential centrifugation and characterized in both their size and zeta potential. Treatment of RBCs with 4-bromo-A23187 (positive control), lysophosphatidic acid (LPA), or phorbol-12 myristate-13 acetate (PMA) in the presence of 2 mM extracellular Ca2+ led to an alteration of cell volume and cell morphology. In stimulated RBCs, exposure of phosphatidylserine (PS) and formation of MVs were observed by using annexin V-FITC. The shedding of MVs was also observed in the case of PMA treatment in the absence of Ca2+, especially under the transmitted bright field illumination. By using SEM, AFM and DLS the morphology and size of stimulated RBCs, MVs were characterized. The sizes of the two populations of MVs were 205.8 ± 51.4 nm and 125.6 ± 31.4 nm, respectively. Adhesion of stimulated RBCs and MVs was observed. The zeta potential of MVs was determined in the range from - 40 mV to - 10 mV depended on the solutions and buffers used. An

  15. Optical evaluation of red blood cell geometry using micropipette aspiration.

    PubMed

    Engström, K G; Möller, B; Meiselman, H J

    1992-01-01

    Although red blood cell (RBC) geometry has been extensively studied by micropipette aspiration, the small size of RBC and pipettes vs. the optical resolution of light microscopy suggests the need to consider potential errors. The present study addressed such difficulties and investigated four specific problems: (1) use of exact equations to calculate RBC membrane area and volume; (2) calibration of the pipette internal diameter (PID); (3) correction for a noncylindrical pipette barrel; (4) diffraction distortion of the RBC image. The observed PID represents a cylinder lens enlargement that can be theoretically derived from the glass/buffer refractive index ratio (1.49/1.33 = 1.12). This enlargement was experimentally confirmed by: (1) studying pipettes bent to allow measurement through the barrel (horizontal) and at the orifice (vertical), with a resulting diameter ratio of 1.12 +/- 0.01; (2) and by replacing the surrounding buffer with immersion oil and hence abolishing the lens phenomenon (ratio = 1.12 +/- 0.02). In addition, use of aspirated oil droplets demonstrated a 3.2 +/- 0.2% error when the PID is focused at a sharp, maximum diameter. The average pipette cone angle was 1.49 +/- 0.09 degrees and varied considerably with pipette pulling procedures; calculated tongue geometry inside the pipette was affected by the noncylindrical pipette barrel. The RBC diffraction error, demonstrated by touching two aspirated cells held by opposing pipettes, was 0.091 +/- 0.002 microns. The PID, cone angle, and diffraction artifacts significantly (p < 0.001) affected calculated RBC geometry (average errors up to 5.4% for area and 9.6% for volume). Two new methods to calculate, rather than directly measure, the PID from images of a single RBC, during either osmotic or pressure manipulation, were evaluated; the osmotic method closely predicted the PID, whereas the pressure method markedly underestimated the PID. Our results thus confirm the need to consider the above

  16. Perturbation of red blood cell membrane rigidity by extracellular ligands.

    PubMed

    Paulitschke, M; Nash, G B; Anstee, D J; Tanner, M J; Gratzer, W B

    1995-07-01

    It is known that binding of extracellular antibodies against the major sialoglycoprotein, glycophorin A, reduced the deformability of the red blood cell membrane. This has been taken to result from new or altered interactions between the glycophorin A and the membrane skeleton. We have shown by means of the micropipette aspiration technique that antibodies against the preponderant transmembrane protein, band 3, induce similar effects. A definite but much smaller reduction in elasticity of the membrane is engendered by univalent Fab fragments of the anti-band 3 antibodies. By examining cells genetically devoid of glycophorin A or containing a variant of this constituent, truncated at the inner membrane surface, we have shown that the anti-band 3 antibodies do not act through the band 3-associated glycophorin A. We examined the effect of anti-glycophorin A antibodies on homozygous Wr(a+b-) cells, in which an amino acid replacement in band 3 annihilates the Wright b (Wrb) epitope (comprising sequence elements of glycophorin A and band 3) and thus, by implication disrupts or perturbs the band 3-glycophorin A interaction; these cells show a much smaller response to an anti-glycophorin A antibody than do normal controls. We infer that in this case anti-glycophorin A antibodies exert their rigidifying effect through the associated band 3. Another anti-glycophorin A antibody, directed against an epitope remote from the membrane surface, however, increases the rigidity of both Wr(a+b-) and normal cells. This implies that not all antibodies act in the same manner in modifying the membrane mechanical properties. The effect exerted by anti-band 3 antibodies appears not to be transmitted through the band 3-ankyrin-spectrin pathway because the rigidifying effect of the intact antibody persists at alkaline pH, at which there is evidence that the ankyrin-band 3 link is largely dissociated. The large difference between the effects of saturating concentrations of the divalent and

  17. Lowering of blood pressure by increasing hematocrit with non nitric oxide scavenging red blood cells.

    PubMed

    Salazar Vázquez, Beatriz Y; Cabrales, Pedro; Tsai, Amy G; Johnson, Paul C; Intaglietta, Marcos

    2008-02-01

    Isovolemic exchange transfusion of 40% of the blood volume in awake hamsters was used to replace native red blood cells (RBCs) with RBCs whose hemoglobin (Hb) was oxidized to methemoglobin (MetHb), MetRBCs. The exchange maintained constant blood volume and produced different final hematocrits (Hcts), varying from 48 to 62% Hct. Mean arterial pressure (MAP) did not change after exchange transfusion, in which 40% of the native RBCs were replaced with MetRBCs, without increasing Hct. Increasing Hct with MetRBCs lowered MAP by 12 mm Hg when Hct was increased 12% above baseline. Further increases of Hct with MetRBCs progressively returned MAP to baseline, which occurred at 62% Hct, a 30% increase in Hct from baseline. These observations show a parabolic "U" shaped distribution of MAP against the change in Hct. Cardiac index, cardiac output divided by body weight, increased between 2 and 17% above baseline for the range of Hcts tested. Peripheral vascular resistance (VR) was decreased 18% from baseline when Hct was increased 12% from baseline. VR and MAP were above baseline for increases in Hct higher than 30%. However, vascular hindrance, VR normalized by blood viscosity (which reflects the contribution of vascular geometry), was lower than baseline for all the increases in Hct tested with MetRBC, indicating prevalence of vasodilation. These suggest that acute increases in Hct with MetRBCs increase endothelium shear stress and stimulate the production of vasoactive factors (e.g., nitric oxide [NO]). When MetRBCs were compared with functional RBCs, vasodilation was augmented for MetRBCs probably due to the lower NO scavenging of MetHb. Consequently, MetRBCs increased the viscosity related hypotension range compared with functional RBCs as NO shear stress vasodilation mediated responses are greater.

  18. Discrimination between red blood cell and platelet components of blood clots by MR microscopy.

    PubMed

    Vidmar, Jernej; Sersa, Igor; Kralj, Eduard; Tratar, Gregor; Blinc, Ales

    2008-09-01

    Magnetic resonance imaging (MRI) of pulmonary emboli obtained ex vivo, verified by immunohistochemistry, showed that platelet layers display brighter signal intensity than areas containing predominantly red blood cells (RBC) in T1-weighted MRI. These results were surprising since platelets do not contain paramagnetic haemoglobin that would enhance magnetic relaxation. Our assumption was that the fibrin meshwork areas with entrapped RBC retain abundant extracellular space filled with serum, whereas platelets regroup into tight aggregates lacking serum, essentially mimicking solid tissue structure, rich with cellular proteins that enhance T1-relaxation. Our hypothesis was examined by MRI and NMR relaxometry of in vitro RBC suspensions and sedimented platelets, as well as by MRI of model clots and pulmonary emboli obtained ex vivo. Pure sedimented platelets exhibited shorter proton spin lattice relaxation times (T1 = 874 +/- 310 ms) than those of venous blood of a healthy male with 40% haematocrit (T1 = 1277 +/- 66 ms). T1-values of RBC samples containing high haematocrit (> or = 80%) resembled T1 of platelet samples. In T1-weighted spin-echo MRI echo time and repetition time (TE/TR = 10/120 ms) the ratio of signal intensities between a non-retracted whole blood clot (with a haematocrit of 35%) and a pure platelet clot was 3.0, and the ratio between a retracted whole blood clot with an estimated haematocrit of about 58% and a pure platelet clot was 2.6. We conclude that T1-weighted MRI can discriminate between platelet layers of thrombi and RBC-rich areas of thrombi that are not compacted to a haematocrit level of > or = 80%.

  19. Statistical dynamics of flowing red blood cells by morphological image processing.

    PubMed

    Higgins, John M; Eddington, David T; Bhatia, Sangeeta N; Mahadevan, L

    2009-02-01

    Blood is a dense suspension of soft non-Brownian cells of unique importance. Physiological blood flow involves complex interactions of blood cells with each other and with the environment due to the combined effects of varying cell concentration, cell morphology, cell rheology, and confinement. We analyze these interactions using computational morphological image analysis and machine learning algorithms to quantify the non-equilibrium fluctuations of cellular velocities in a minimal, quasi-two-dimensional microfluidic setting that enables high-resolution spatio-temporal measurements of blood cell flow. In particular, we measure the effective hydrodynamic diffusivity of blood cells and analyze its relationship to macroscopic properties such as bulk flow velocity and density. We also use the effective suspension temperature to distinguish the flow of normal red blood cells and pathological sickled red blood cells and suggest that this temperature may help to characterize the propensity for stasis in Virchow's Triad of blood clotting and thrombosis.

  20. Comparative study of red blood cell method in rat and calves blood as alternatives of Draize eye irritation test.

    PubMed

    Lagarto, A; Vega, R; Vega, Y; Guerra, I; González, R

    2006-06-01

    Red blood cell assay (RBC) is used to estimate potential irritation of tensioactive agents and detergents. Cell membrane lysis and cell protein denaturation are measured photometrically. This study was aimed to determine if rat blood cells can be used to predict eye potential irritation in the same way of calves blood cells in RBC assay. We evaluated 20 cosmetic formulations using rat and calves blood according to INVITOX protocol No 37. Data of media hemolysis concentration, denaturation index and the ratio of both parameters were compared with in vivo data of eye irritancy. There was a significant difference (p<0.01) between H50 value when evaluated the standard SDS with red blood cell method in rat and calves blood. According to the exact probability of Fisher taking as approach the acceptance or rejection of the substance there are no significant differences between in vitro assay with calves blood and in vivo results. Not happening the same way for the RBC assay with rat blood where significant differences were obtained (p<0.01) among the classification of in vitro and in vivo test. The RBC assay using calves blood showed better results. Several test substances were false negatives with rat blood. This high false negative rate would be correctly identified by the animal test but it may also lead to increased animal consumption. For that RBC assay with calf blood cells is preferable to the employment of rat blood as screening method with a reduction and refinement strategy.

  1. A Stability Result on the Orientation of Red Blood Cells in the Venule Network

    NASA Astrophysics Data System (ADS)

    Munganga, J. M. W.; Maritz, R.

    2011-06-01

    We model blood as a non-Newtonian fluid. Red blood cells, white blood cells and platelets immersed in plasma, are modeled as a suspension where the particles, erythrocyte cell aggregates, are assumed to be in the shape of a rigid cylinder. The orientation of these particles is affected by various factors. In this article we look at the effect of magnetic fields on the orientation of these red blood cell particles. A proof of stability of solutions is given, under the assumption that the body is subjected to the effect of magnetic fields.

  2. Particle Method Computation of the Red Blood Cell Motion in Malaria Infection

    NASA Astrophysics Data System (ADS)

    Yamaguchi, Takami; Imai, Yosuke; Ishikawa, Takuji

    2010-09-01

    We developed a numerical model of blood flow in malaria infection. Our model was based on a particle method. All the components of blood were represented by finite number of particles. The membrane of red blood cells was modeled by triangular network of membrane particles. Stretch resistance and bending resistance were considered. The force generated by the deformation of membrane was substituted into the force term of Navier-Stokes equations only for membrane particles. The malaria parasite was assumed as a rigid object. Some interesting behavior of the infected and healthy red blood cells were simulated.

  3. Direct In Vivo Electrochemical Detection of Haemoglobin in Red Blood Cells

    NASA Astrophysics Data System (ADS)

    Toh, Rou Jun; Peng, Weng Kung; Han, Jongyoon; Pumera, Martin

    2014-08-01

    The electrochemical behavior of iron ion in haemoglobin provides insight to the chemical activity in the red blood cell which is important in the field of hematology. Herein, the detection of haemoglobin in human red blood cells on glassy carbon electrode (GC) was demonstrated. Red blood cells or raw blood cells was immobilized on a glassy carbon electrode surface with Nafion films employed to sandwich the layer of biological sample firmly on the electrode surface. Cyclic voltammetry (CV) analyses revealed a well-defined reduction peak for haemoglobin at about -0.30 V (vs. Ag/AgCl) at the red blood cell (GC-Nf-RBC-3Nf) and blood (GC-Nf-B-3Nf) film modified GCE in a pH 3.5 phosphate buffer solution. We further demonstrated that the complex biological conditions of a human red blood cell displayed no interference with the detection of haemoglobin. Such findings shall have an implication on the possibilities of studying the electrochemical behaviour of haemoglobin directly from human blood, for various scientific and clinical purposes.

  4. Direct in vivo electrochemical detection of haemoglobin in red blood cells.

    PubMed

    Toh, Rou Jun; Peng, Weng Kung; Han, Jongyoon; Pumera, Martin

    2014-08-28

    The electrochemical behavior of iron ion in haemoglobin provides insight to the chemical activity in the red blood cell which is important in the field of hematology. Herein, the detection of haemoglobin in human red blood cells on glassy carbon electrode (GC) was demonstrated. Red blood cells or raw blood cells was immobilized on a glassy carbon electrode surface with Nafion films employed to sandwich the layer of biological sample firmly on the electrode surface. Cyclic voltammetry (CV) analyses revealed a well-defined reduction peak for haemoglobin at about -0.30 V (vs. Ag/AgCl) at the red blood cell (GC-Nf-RBC-3Nf) and blood (GC-Nf-B-3Nf) film modified GCE in a pH 3.5 phosphate buffer solution. We further demonstrated that the complex biological conditions of a human red blood cell displayed no interference with the detection of haemoglobin. Such findings shall have an implication on the possibilities of studying the electrochemical behaviour of haemoglobin directly from human blood, for various scientific and clinical purposes.

  5. Direct In Vivo Electrochemical Detection of Haemoglobin in Red Blood Cells

    PubMed Central

    Toh, Rou Jun; Peng, Weng Kung; Han, Jongyoon; Pumera, Martin

    2014-01-01

    The electrochemical behavior of iron ion in haemoglobin provides insight to the chemical activity in the red blood cell which is important in the field of hematology. Herein, the detection of haemoglobin in human red blood cells on glassy carbon electrode (GC) was demonstrated. Red blood cells or raw blood cells was immobilized on a glassy carbon electrode surface with Nafion films employed to sandwich the layer of biological sample firmly on the electrode surface. Cyclic voltammetry (CV) analyses revealed a well-defined reduction peak for haemoglobin at about −0.30 V (vs. Ag/AgCl) at the red blood cell (GC-Nf-RBC-3Nf) and blood (GC-Nf-B-3Nf) film modified GCE in a pH 3.5 phosphate buffer solution. We further demonstrated that the complex biological conditions of a human red blood cell displayed no interference with the detection of haemoglobin. Such findings shall have an implication on the possibilities of studying the electrochemical behaviour of haemoglobin directly from human blood, for various scientific and clinical purposes. PMID:25163492

  6. Platelet and red blood cell utilization and transfusion independence in umbilical cord blood and allogeneic peripheral blood hematopoietic cell transplants.

    PubMed

    Solh, Melhem; Brunstein, Claudio; Morgan, Shanna; Weisdorf, Daniel

    2011-05-01

    Allogeneic hematopoietic cell transplantation (HCT) recipients have substantial transfusion requirements. Factors associated with increased transfusions and the extent of blood product use in umbilical cord blood (UCB) recipients are uncertain. We reviewed blood product use in 229 consecutive adult recipients of allogeneic HCT at the University of Minnesota: 147 with leukemia, 82 lymphoma or myeloma; 58% received unrelated UCB and 43% sibling donor peripheral blood stem cell (PBSC) grafts. Although neutrophil recovery was prompt (UCB median 17, range: 2-45 days, and PBSC 14, range: 3-34 days), only 135 of 229 (59% cumulative incidence) achieved red blood cell (RBC) independence and 157 (69%) achieved platelet independence by 6 months. Time to platelet independence was prolonged in UCB recipients (median UCB 41 versus PBSC 14 days) and in patients who had received a prior transplant (median 48 versus 32 days). Patients who received UCB grafts required more RBC through day 60 post-HCT (mean UCB 7.8 (95% confidence interval [CI] 6.7-8.9) versus PBSC 5.2 (3.7-6.7) transfusions, P = .04), and more platelet transfusions (mean 25.2 (95% CI 22.1-28.2) versus 12.9 (9.4-16.4), P < .01) compared to PBSC recipients. Patients receiving myeloablative (MA) conditioning required more RBC and platelet transfusions during the first 2 months post-HCT compared to reduced-intensity conditioning (RIC) (7.4 versus 6.2, P = .30 for RBC; 23.2 versus 17.5, P = .07 for platelets). Despite prompt neutrophil engraftment, UCB recipients had delayed platelet recovery as well as more prolonged and costly blood product requirements. Enhanced approaches to accelerate multilineage engraftment could limit the transfusion-associated morbidity and costs accompanying UCB allotransplantation.

  7. Bio-inspired cryo-ink preserves red blood cell phenotype and function during nanoliter vitrification.

    PubMed

    El Assal, Rami; Guven, Sinan; Gurkan, Umut Atakan; Gozen, Irep; Shafiee, Hadi; Dalbeyler, Sedef; Abdalla, Noor; Thomas, Gawain; Fuld, Wendy; Illigens, Ben M W; Estanislau, Jessica; Khoory, Joseph; Kaufman, Richard; Zylberberg, Claudia; Lindeman, Neal; Wen, Qi; Ghiran, Ionita; Demirci, Utkan

    2014-09-03

    Current red-blood-cell cryopreservation methods utilize bulk volumes, causing cryo-injury of cells, which results in irreversible disruption of cell morphology, mechanics, and function. An innovative approach to preserve human red-blood-cell morphology, mechanics, and function following vitrification in nanoliter volumes is developed using a novel cryo-ink integrated with a bioprinting approach. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. A role for activated endothelial cells in red blood cell clearance: implications for vasopathology.

    PubMed

    Fens, Marcel H A M; van Wijk, Richard; Andringa, Grietje; van Rooijen, Karlijn L; Dijstelbloem, Hilde M; Rasmussen, Jan T; de Vooght, Karen M K; Schiffelers, Raymond M; Gaillard, Carlo A J M; van Solinge, Wouter W

    2012-04-01

    Phosphatidylserine exposure by red blood cells is acknowledged as a signal that initiates phagocytic removal of the cells from the circulation. Several disorders and conditions are known to induce phosphatidylserine exposure. Removal of phosphatidylserine-exposing red blood cells generally occurs by macrophages in the spleen and liver. Previously, however, we have shown that endothelial cells are also capable of erythrophagocytosis. Key players in the erythrophagocytosis by endothelial cells appeared to be lactadherin and α(v)-integrin. Phagocytosis via the phosphatidylserine-lactadherin-α(v)-integrin pathway is the acknowledged route for removal of apoptotic innate cells by phagocytes. Endothelial cell phagocytosis of red blood cells was further explored using a more (patho)physiological approach. Red blood cells were exposed to oxidative stress, induced by tert-butyl hydroperoxide. After opsonization with lactadherin, red blood cells were incubated with endothelial cells to study erythrophagocytosis and examine cytotoxicity. Red blood cells exposed to oxidative stress show alterations such as phosphatidylserine exposure and loss of deformability. When incubated with endothelial cells, marked erythrophagocytosis occurred in the presence of lactadherin under both static and flow conditions. As a consequence, intracellular organization was disturbed and endothelial cells were seen to change shape ('rounding up'). Increased expression of apoptotic markers indicated that marked erythrophagocytosis has cytotoxic effects. Activated endothelial cells show significant phagocytosis of phosphatidylserine-exposing and rigid red blood cells under both static and flow conditions. This results in a certain degree of cytotoxicity. We postulate that activated endothelial cells play a role in red blood cell clearance in vivo. Significant erythrophagocytosis can induce endothelial cell loss, which may contribute to vasopathological effects as seen, for instance, in sickle cell

  9. A role for activated endothelial cells in red blood cell clearance: implications for vasopathology

    PubMed Central

    Fens, Marcel H.A.M.; van Wijk, Richard; Andringa, Grietje; van Rooijen, Karlijn L.; Dijstelbloem, Hilde M.; Rasmussen, Jan T.; de Vooght, Karen M.K.; Schiffelers, Raymond M.; Gaillard, Carlo A.J.M.; van Solinge, Wouter W.

    2012-01-01

    Background Phosphatidylserine exposure by red blood cells is acknowledged as a signal that initiates phagocytic removal of the cells from the circulation. Several disorders and conditions are known to induce phosphatidylserine exposure. Removal of phosphatidylserine-exposing red blood cells generally occurs by macrophages in the spleen and liver. Previously, however, we have shown that endothelial cells are also capable of erythrophagocytosis. Key players in the erythrophagocytosis by endothelial cells appeared to be lactadherin and αv-integrin. Phagocytosis via the phosphatidylserine-lactadherin-αv-integrin pathway is the acknowledged route for removal of apoptotic innate cells by phagocytes. Design and Methods Endothelial cell phagocytosis of red blood cells was further explored using a more (patho)physiological approach. Red blood cells were exposed to oxidative stress, induced by tert-butyl hydroperoxide. After opsonization with lactadherin, red blood cells were incubated with endothelial cells to study erythrophagocytosis and examine cytotoxicity. Results Red blood cells exposed to oxidative stress show alterations such as phosphatidylserine exposure and loss of deformability. When incubated with endothelial cells, marked erythrophagocytosis occurred in the presence of lactadherin under both static and flow conditions. As a consequence, intracellular organization was disturbed and endothelial cells were seen to change shape (‘rounding up’). Increased expression of apoptotic markers indicated that marked erythrophagocytosis has cytotoxic effects. Conclusions Activated endothelial cells show significant phagocytosis of phosphatidylserine-exposing and rigid red blood cells under both static and flow conditions. This results in a certain degree of cytotoxicity. We postulate that activated endothelial cells play a role in red blood cell clearance in vivo. Significant erythrophagocytosis can induce endothelial cell loss, which may contribute to

  10. Dynamical Modes of Deformed Red Blood Cells and Lipid Vesicles in Flows

    NASA Astrophysics Data System (ADS)

    Noguchi, H.

    Red blood cells and lipid vesicles exhibit rich behaivor in flows.Their dynamics were studied using a particle-based hydrodynamic simulation method, multi-particle collision dynamics. Rupture of lipid vesicles in simple shear flow was simulated by meshless membrane model. Several shape transitions of lipid vesicles and red blood cells are induced by flows. Transition of a lipid vesicle from budded to prolate shapes with increasing shear rate and ordered alignments of deformed elastic vesicles in high density are presented.

  11. The mode of action of some antibiotics on red blood cell membranes.

    PubMed

    Blaskó, K; Shagina, L V; Györgyi, S; Lev, A A

    1986-12-01

    Data are presented on the interaction of gramicidin, primycin and valinomycin with red blood cell membranes and compared with those obtained for artificial lipid bilayer membranes. The channel forming antibiotics gramicidin and primycin show specific kinetic behaviour in living cell membranes. It could be shown that the penetration of these antibiotics into the red blood cell membrane is a cooperative process resulting in the occurrence of aggregates in the lipid lattice of the membrane.

  12. Inhibition of Platelet Aggregation by Supernates from Stored Red Blood Cells

    DTIC Science & Technology

    2010-04-01

    platelet aggregates in fresh whole blood.[10] In those experiments , we observed that platelets in blood incubated with supernates from stored RBC...volumes in sterile cryovials, and the vials were stored at -80C. For each experiment , aliquots were thawed quickly in a 37°C water bath just before...The final ratio of whole blood to supernate was 2:1. For each experiment , blood was collected first into one red top Vacutainer tube (no anti

  13. Effects of Aged Stored Autologous Red Blood Cells on Human Endothelial Function

    PubMed Central

    Kanias, Tamir; Triulzi, Darrel; Donadee, Chenell; Barge, Suchitra; Badlam, Jessica; Jain, Shilpa; Belanger, Andrea M.; Kim-Shapiro, Daniel B.

    2015-01-01

    Rationale: A major abnormality that characterizes the red cell “storage lesion” is increased hemolysis and reduced red cell lifespan after infusion. Low levels of intravascular hemolysis after transfusion of aged stored red cells disrupt nitric oxide (NO) bioavailabity, via accelerated NO scavenging reaction with cell-free plasma hemoglobin. The degree of intravascular hemolysis post-transfusion and effects on endothelial-dependent vasodilation responses to acetylcholine have not been fully characterized in humans. Objectives: To evaluate the effects of blood aged to the limits of Food and Drug Administration–approved storage time on the human microcirculation and endothelial function. Methods: Eighteen healthy individuals donated 1 U of leukopheresed red cells, divided and autologously transfused into the forearm brachial artery 5 and 42 days after blood donation. Blood samples were obtained from stored blood bag supernatants and the antecubital vein of the infusion arm. Forearm blood flow measurements were performed using strain-gauge plethysmography during transfusion, followed by testing of endothelium-dependent blood flow with increasing doses of intraarterial acetylcholine. Measurements and Main Results: We demonstrate that aged stored blood has higher levels of arginase-1 and cell-free plasma hemoglobin. Compared with 5-day blood, the transfusion of 42-day packed red cells decreases acetylcholine-dependent forearm blood flows. Intravascular venous levels of arginase-1 and cell-free plasma hemoglobin increase immediately after red cell transfusion, with more significant increases observed after infusion of 42-day-old blood. Conclusions: We demonstrate that the transfusion of blood at the limits of Food and Drug Administration–approved storage has a significant effect on the forearm circulation and impairs endothelial function. Clinical trial registered with www.clinicaltrials.gov (NCT 01137656) PMID:26222884

  14. Effects of Aged Stored Autologous Red Blood Cells on Human Endothelial Function.

    PubMed

    Risbano, Michael G; Kanias, Tamir; Triulzi, Darrel; Donadee, Chenell; Barge, Suchitra; Badlam, Jessica; Jain, Shilpa; Belanger, Andrea M; Kim-Shapiro, Daniel B; Gladwin, Mark T

    2015-11-15

    A major abnormality that characterizes the red cell "storage lesion" is increased hemolysis and reduced red cell lifespan after infusion. Low levels of intravascular hemolysis after transfusion of aged stored red cells disrupt nitric oxide (NO) bioavailabity, via accelerated NO scavenging reaction with cell-free plasma hemoglobin. The degree of intravascular hemolysis post-transfusion and effects on endothelial-dependent vasodilation responses to acetylcholine have not been fully characterized in humans. To evaluate the effects of blood aged to the limits of Food and Drug Administration-approved storage time on the human microcirculation and endothelial function. Eighteen healthy individuals donated 1 U of leukopheresed red cells, divided and autologously transfused into the forearm brachial artery 5 and 42 days after blood donation. Blood samples were obtained from stored blood bag supernatants and the antecubital vein of the infusion arm. Forearm blood flow measurements were performed using strain-gauge plethysmography during transfusion, followed by testing of endothelium-dependent blood flow with increasing doses of intraarterial acetylcholine. We demonstrate that aged stored blood has higher levels of arginase-1 and cell-free plasma hemoglobin. Compared with 5-day blood, the transfusion of 42-day packed red cells decreases acetylcholine-dependent forearm blood flows. Intravascular venous levels of arginase-1 and cell-free plasma hemoglobin increase immediately after red cell transfusion, with more significant increases observed after infusion of 42-day-old blood. We demonstrate that the transfusion of blood at the limits of Food and Drug Administration-approved storage has a significant effect on the forearm circulation and impairs endothelial function. Clinical trial registered with www.clinicaltrials.gov (NCT 01137656).

  15. Why and how does collective red blood cells motion occur in the blood microcirculation?

    NASA Astrophysics Data System (ADS)

    Ghigliotti, Giovanni; Selmi, Hassib; Asmi, Lassaad El; Misbah, Chaouqi

    2012-10-01

    The behaviour of red blood cells (RBCs), modelled as vesicles, in Poiseuille flow, mimicking the microvasculature, is studied with numerical simulations in two dimensions. RBCs moving in the centre of the Poiseuille flow (as in blood capillaries) are shown to attract each other and form clusters only due to hydrodynamic interactions, provided that their distance at a given time is below a certain critical value. This distance depends on physical parameters, such as the flow strength. Our simulations reveal that clusters are unstable above a threshold value in the number of forming RBCs, beyond which one or few cells escape the pack by a self-regulating mechanism that select the marginally stable size. This size selection depends on the flow strength as well as on the RBC swelling ratio. The results are interpreted via the analysis of the perturbation of the flow field induced by the vesicles and the interplay with bending and tension forces. This sheds a novel light on the process of collective motion of RBCs observed in vivo.

  16. Acute and chronic influence of temperature on red blood cell anion exchange.

    PubMed

    Jensen, F B; Wang, T; Brahm, J

    2001-01-01

    Unidirectional (36)Cl(-) efflux via the red blood cell anion exchanger was measured under Cl(-) self-exchange conditions (i.e. no net flow of anions) in rainbow trout Oncorhynchus mykiss and red-eared freshwater turtle Trachemys scripta to examine the effects of acute temperature changes and acclimation temperature on this process. We also evaluated the possible adaptation of anion exchange to different temperature regimes by including our previously published data on other animals. An acute temperature increase caused a significant increase in the rate constant (k) for unidirectional Cl(-) efflux in rainbow trout and freshwater turtle. After 3 weeks of temperature acclimation, 5 degrees C-acclimated rainbow trout showed only marginally higher Cl(-) transport rates than 15 degrees C-acclimated trout when compared at the same temperature. Apparent activation energies for red blood cell Cl(-) exchange in trout and turtle were lower than values reported in endothermic animals. The Q(10) for red blood cell anion exchange was 2.0 in trout and 2.3 in turtle, values close to those for CO(2) excretion, suggesting that, in ectothermic animals, the temperature sensitivity of band-3-mediated anion exchange matches the temperature sensitivity of CO(2) transport (where red blood cell Cl(-)/HCO(3)(-) exchange is a rate-limiting step). In endotherms, such as man and chicken, Q(10) values for red blood cell anion exchange are considerably higher but are no obstacle to CO(2) transport, because body temperature is normally kept constant at values at which anion exchange rates are high. When compared at constant temperature, red blood cell Cl(-) permeability shows large differences among species (trout, carp, eel, cod, turtle, alligator, chicken and man). Cl(-) permeabilities are, however, remarkable similar when compared at preferred body temperatures, suggesting an appropriate evolutionary adaptation of red blood cell anion exchange function to the different thermal niches occupied

  17. Diagnosis of Western Red Cedar Asthma Using a Blood-based Gene Expression Biomarker Panel.

    PubMed

    Yang, Chen Xi; Singh, Amrit; Kim, Young Woong; Conway, Edward M; Carlsten, Christopher; Tebbutt, Scott J

    2017-05-02

    Western red cedar asthma is the most common form of occupational asthma in the Pacific Northwest region of North America and is caused by a low molecular weight molecule, plicatic acid, found in western red cedar wood. In the present study, peripheral whole blood transcriptomics was used to identify biomarker panels that distinguish asthmatic individuals who are sensitive to plicatic acid from asthmatic individuals who are not sensitive to plicatic acid. These findings suggest that blood may be used as a resource to diagnose western red cedar asthma.

  18. Red blood cell plasmalogens and docosahexaenoic acid are independently reduced in primary open-angle glaucoma.

    PubMed

    Acar, Niyazi; Berdeaux, Olivier; Juaneda, Pierre; Grégoire, Stéphane; Cabaret, Stéphanie; Joffre, Corinne; Creuzot-Garcher, Catherine P; Bretillon, Lionel; Bron, Alain M

    2009-12-01

    Among several theories involved in the pathogenesis of primary open-angle glaucoma (POAG), the vascular theory considers the disease to be a consequence of reduced ocular blood flow associated with red blood cell abnormalities. Red blood cell membrane structure and function are influenced by their phospholipid composition. We investigated whether specific lipid entities that may affect the membrane physiology, namely, polyunsaturated fatty acids (PUFAs) and plasmalogens, are modified in POAG and whether these potential variations are related to the stage of glaucoma. Blood samples were collected from 31 POAG patients and 10 healthy individuals. The stage of glaucoma was determined according to the Hodapp and Parrish classification. Lipids were extracted from red blood cell membranes and individual phospholipid species were quantified by liquid chromatography combined with mass spectrometry using triple quadrupole technology. POAG patients had reduced erythrocyte levels of phosphatidyl-choline (PC) carrying docosahexaenoic acid (DHA). POAG patients also displayed lower levels of choline plasmalogens (PlsC) carrying PUFAs other than DHA. These differences were greater as the severity of the disease increased. Linear regressions predicted that red blood cell PlsC levels would decrease years before clinical symptoms, whereas the levels of PC carrying DHA were linearly correlated to visual field loss. Our data demonstrate the selective loss of some individual phospholipid species in red blood cell membranes, which may partly explain their loss of flexibility in POAG.

  19. Comparison of instruments for investigation of microcirculatory blood flow and red blood cell concentration.

    PubMed

    O'Doherty, Jim; McNamara, Paul; Clancy, Neil T; Enfield, Joey G; Leahy, Martin J

    2009-01-01

    The use of laser Doppler perfusion imaging (LDPI) and laser speckle perfusion imaging (LSPI) is well known in the noninvasive investigation of microcirculatory blood flow. This work compares the two techniques with the recently developed tissue viability (TiVi) imaging system, which is proposed as a useful tool to quantify red blood cell concentration in microcirculation. Three systems are evaluated with common skin tests such as the use of vasodilating and vasoconstricting drugs (methlynicotinate and clobetasol, respectively) and a reactive hyperaemia maneuver (using a sphygmomanometer). The devices investigated are the laser Doppler line scanner (LDLS), the laser speckle perfusion imager (FLPI)-both from Moor Instruments (Axminster, United Kingdom)-and the TiVi imaging system (WheelsBridge AB, Linkoping, Sweden). Both imaging and point scanning by the devices are used to quantify the provoked reactions. Perfusion images of vasodilatation and vasoconstriction are acquired with both LDLS and FLPI, while TiVi images are acquired with the TiVi imager. Time acquisitions of an averaged region of interest are acquired for temporal studies such as the reactive hyperaemia. In contrast to the change in perfusion over time with pressure, the TiVi imager shows a different response due its measurement of blood concentration rather than perfusion. The responses can be explained by physiological understanding. Although the three devices sample different compartments of tissue, and output essentially different variables, comparisons can be seen between the three systems. The LDLS system proves to be suited to measurement of perfusion in deeper vessels, while FLPI and TiVi showed sensitivity to more superficial nutritional supply. LDLS and FLPI are insensitive to the action of the vasoconstrictor, while TiVi shows the clear boundaries of the reaction. Assessment of the resolution, penetration depth, and acquisition rate of each instrument show complimentary features that should

  20. Blood analyte sensing using fluorescent dye-loaded red blood cells

    NASA Astrophysics Data System (ADS)

    Ritter, Sarah C.; Shao, Xiaole; Cooley, Nicholas; Milanick, Mark A.; Glass, Timothy E.; Meissner, Kenith E.

    2014-02-01

    Measurement of blood analytes provides crucial information about a patient's health. Some such analytes, such as glucose in the case of diabetes, require long-term or near-continuous monitoring for proper disease management. However, current monitoring techniques are far from ideal: multiple-per-day finger stick tests are inconvenient and painful for the patient; implantable sensors have short functional life spans (i.e., 3-7 days). Due to analyte transporters on red blood cell (RBC) membranes that equilibrate intracellular and extracellular analyte levels, RBCs serve as an attractive alternative for encapsulating analyte sensors. Once reintroduced to the blood stream, the functionalized RBCs may continue to live for the remainder of their life span (120 days for humans). They are biodegradable and biocompatible, thereby eliminating the immune system response common for many implanted devices. The proposed sensing system utilizes the ability of the RBCs to swell in response to a decrease in the osmolarity of the extracellular solution. Just before lysis, they develop small pores on the scale of tens of nanometers. While at low temperature, analyte-sensitive dyes in the extracellular solution diffuse into the perforated RBCs and become entrapped upon restoration of temperature and osmolarity. Since the fluorescent signal from the entrapped dye reports on changes in the analyte level of the extracellular solution via the RBC transporters, interactions between the RBCs and the dye are critical to the efficacy of this technique. In this work, we study the use of a near infrared pH sensitive dye encapsulated within RBCs and assess the ability to measure dye fluorescence in vivo.

  1. Comparison of instruments for investigation of microcirculatory blood flow and red blood cell concentration

    NASA Astrophysics Data System (ADS)

    O'Doherty, Jim; McNamara, Paul; Clancy, Neil T.; Enfield, Joey G.; Leahy, Martin J.

    2009-05-01

    The use of laser Doppler perfusion imaging (LDPI) and laser speckle perfusion imaging (LSPI) is well known in the noninvasive investigation of microcirculatory blood flow. This work compares the two techniques with the recently developed tissue viability (TiVi) imaging system, which is proposed as a useful tool to quantify red blood cell concentration in microcirculation. Three systems are evaluated with common skin tests such as the use of vasodilating and vasoconstricting drugs (methlynicotinate and clobetasol, respectively) and a reactive hyperaemia maneuver (using a sphygmomanometer). The devices investigated are the laser Doppler line scanner (LDLS), the laser speckle perfusion imager (FLPI)-both from Moor Instruments (Axminster, United Kingdom)-and the TiVi imaging system (WheelsBridge AB, Linköping, Sweden). Both imaging and point scanning by the devices are used to quantify the provoked reactions. Perfusion images of vasodilatation and vasoconstriction are acquired with both LDLS and FLPI, while TiVi images are acquired with the TiVi imager. Time acquisitions of an averaged region of interest are acquired for temporal studies such as the reactive hyperaemia. In contrast to the change in perfusion over time with pressure, the TiVi imager shows a different response due its measurement of blood concentration rather than perfusion. The responses can be explained by physiological understanding. Although the three devices sample different compartments of tissue, and output essentially different variables, comparisons can be seen between the three systems. The LDLS system proves to be suited to measurement of perfusion in deeper vessels, while FLPI and TiVi showed sensitivity to more superficial nutritional supply. LDLS and FLPI are insensitive to the action of the vasoconstrictor, while TiVi shows the clear boundaries of the reaction. Assessment of the resolution, penetration depth, and acquisition rate of each instrument show complimentary features that should

  2. Use of remote blood releasing system for red cell transfusion in hospice care center

    PubMed Central

    Chan, Kwok Ying; Leung, Rock Yuk Yan; Cheung, Ka Chi; Lam, Clarence; Koo, Eleanor; Ng, Sylvia

    2016-01-01

    Objectives: It is quite common to have advanced cancer or end-stage renal disease patients for regular or even frequent blood transfusion in palliative care. However, due to geographical reason in some hospice centers, blood transfusion is sometimes difficult if blood bank is closed during non-office hour or not available. Methods: Here, we reported a new blood releasing system, that is, remote blood releasing system, that could be used safely by nursing staff alone when the blood bank was closed during the night time and holiday. Results: On-call nursing staff could collect red cells successful in these two cases. Conclusion: The new blood releasing system seems useful. However, larger sample sizes and longer period of study are required to estimate its efficacy and safety. The provision of antibody-positive red cells and platelet remained a limitation of this system. PMID:27489720

  3. Radiolabeled red blood cells: status, problems, and prospects

    SciTech Connect

    Srivastava, S.C.

    1983-01-01

    Radionuclidic labels for red cells can be divided into two main categories - cohort or pulse labels, and random labels. The random labels are incorporated into circulating cells of all ages and the labeling process is usually carried out in vitro. The red cell labels in predominant use involve random labeling and employ technetium-99m, chromium-51, indium-111, and gallium-68, roughly in that order. The extent of usefulness depends on the properties of the label such as the half-life, decay mode, and in-vivo stability, etc. Labeled cells can be used for red cell survival measurements when the half-life of the radionuclide is sufficiently long. The major portion of this article deals with random labels.

  4. Early alterations of red blood cell rheology in critically ill patients.

    PubMed

    Reggiori, Giulia; Occhipinti, Giovanna; De Gasperi, Andrea; Vincent, Jean-Louis; Piagnerelli, Michael

    2009-12-01

    To investigate red blood cell rheology in a large intensive care unit population on admission, and to assess the possible influence of comorbidities on the rheology. : Prospective study. Medico-surgical intensive care unit with 31 beds. All intensive care unit admissions during a 5-month period and 20 healthy volunteers. Blood sampling. A total of 196 intensive care patients (160 without and 36 with sepsis) and 20 healthy volunteers were studied. Red blood cell rheology (deformability and aggregation) was assessed ex vivo using the laser-assisted optical rotational cell analyzer (LORCA; Mechatronics Instruments BV, AN Zwaag, Netherlands) within the first 24 hrs after intensive care unit admission. Red blood cell deformability was determined by the elongation index in relation to the shear stress (0.3 to 50 Pa) applied on the red blood cell membrane surface. Aggregation was assessed by the aggregation index. Septic patients were more likely to have anemia, coagulation abnormalities, and comorbidities than were nonseptic patients. Red blood cell deformability was significantly altered in septic compared to nonseptic patients and volunteers for the majority of shear stress rates studied. The aggregation index was greater in septic patients than in volunteers (67.9% [54.7-73.5] vs. 61.8% [58.2-68.4]; p < .05). Only sepsis and hematologic disease influenced the elongation index (both p < .01). Other comorbidities, like cancer, diabetes mellitus, cirrhosis, and terminal renal failure, had no effect on the elongation index. Aggregation index was related to the degree of organ failure (Sequential Organ Failure Assessment score), the red blood cell count, and fibrinogen concentrations. Early alterations of red blood cell rheology are common in intensive care unit patients, especially in those with sepsis. Comorbidities (other than hematologic diseases) do not significantly influence these abnormalities. These alterations could contribute to the microcirculatory alterations

  5. Implementing mass-scale red cell genotyping at a blood center

    PubMed Central

    Flegel, Willy A.; Gottschall, Jerome L.; Denomme, Gregory A.

    2015-01-01

    Background When problems with compatibility beyond ABO and RhD arise, currently transfusion services search their inventories and perform time-consuming serologic testing to locate antigen-negative blood. These clinically important blood group antigens can be detected reliably by red cell genotyping, which is a technology whereby DNA-based techniques are used to evaluate gene polymorphisms that determine the expression of red cell antigens. We introduced mass-scale genotyping and measured availability of genotyped blood. Study design and methods All non-Caucasian donors qualified for genotyping along with Caucasian donors who had a history of repeat donation. Mass-scale red cell genotyping, performed on an electronic interfaced open array platform, was implemented to screen blood donors for 32 SNPs that predicted 42 blood group antigens. Genotype screening results were confirmed by phenotyping, when needed for antigen-negative transfusion, prior to release of the red cell unit. Results Approximately 22,000 donors were red cell genotyped within 4 months and a total of 43,066 donors in 4 years. There were 463 discordances (0.52% of 89,596 genotypes with a phenotype). Among the 307 resolved discordances, approximate equal numbers represented historical serological or genotyping discrepancies (n=151 and n=156, respectively). In the final year of the study, an average of 29% of the daily inventory had a genotype. Conclusions Red cell genotyping of blood donors using an electronic interface created a large and stable supply of red cell units with historical genotypes. The database served the needs of antigen-negative blood requests for a large regional blood center, and allowed us to abandon screening by serology. PMID:26094790

  6. Light scattering by red blood cells in ektacytometry: Fraunhofer versus anomalous diffraction.

    PubMed

    Streekstra, G J; Hoekstra, A G; Nijhof, E J; Heethaar, R M

    1993-05-01

    In the present literature on ektacytometry, small angle light scattering by ellipsoidal red blood cells is commonly approximated by Fraunhofer diffraction. Calculations on a sphere with the size and relative refractive index of a red cell, however, show that Fraunhofer diffraction deviates significantly from exact Mie theory. Anomalous diffraction is found to be a much better approximation. The anomalous diffraction theory is used to calculate the intensity distribution of the light scattered by an ellipsoidally deformed red blood cell. The derived expression shows that the ellipticity of isointensity curves in forward scattered light are equal to the ellipticity of the red blood cell. The theoretical expression is fitted to the intensity patterns measured with an ektacytometer. For the small observation angles used in ektacytometry, the experimental results confirm the validity of the anomalous diffraction approach.

  7. Oxygenated-Blood Colour Change Thresholds for Perceived Facial Redness, Health, and Attractiveness

    PubMed Central

    Re, Daniel E.; Whitehead, Ross D.; Xiao, Dengke; Perrett, David I.

    2011-01-01

    Blood oxygenation level is associated with cardiovascular fitness, and raising oxygenated blood colouration in human faces increases perceived health. The current study used a two-alternative forced choice (2AFC) psychophysics design to quantify the oxygenated blood colour (redness) change threshold required to affect perception of facial colour, health and attractiveness. Detection thresholds for colour judgments were lower than those for health and attractiveness, which did not differ. The results suggest redness preferences do not reflect a sensory bias, rather preferences may be based on accurate indications of health status. Furthermore, results suggest perceived health and attractiveness may be perceptually equivalent when they are assessed based on facial redness. Appearance-based motivation for lifestyle change can be effective; thus future studies could assess the degree to which cardiovascular fitness increases face redness and could quantify changes in aerobic exercise needed to increase facial attractiveness. PMID:21448270

  8. Oxygenated-blood colour change thresholds for perceived facial redness, health, and attractiveness.

    PubMed

    Re, Daniel E; Whitehead, Ross D; Xiao, Dengke; Perrett, David I

    2011-03-23

    Blood oxygenation level is associated with cardiovascular fitness, and raising oxygenated blood colouration in human faces increases perceived health. The current study used a two-alternative forced choice (2AFC) psychophysics design to quantify the oxygenated blood colour (redness) change threshold required to affect perception of facial colour, health and attractiveness. Detection thresholds for colour judgments were lower than those for health and attractiveness, which did not differ. The results suggest redness preferences do not reflect a sensory bias, rather preferences may be based on accurate indications of health status. Furthermore, results suggest perceived health and attractiveness may be perceptually equivalent when they are assessed based on facial redness. Appearance-based motivation for lifestyle change can be effective; thus future studies could assess the degree to which cardiovascular fitness increases face redness and could quantify changes in aerobic exercise needed to increase facial attractiveness.

  9. Biological effects of the electrostatic field: red blood cell-related alterations of oxidative processes in blood

    NASA Astrophysics Data System (ADS)

    Harutyunyan, Hayk A.; Sahakyan, Gohar V.

    2016-01-01

    The aim of this study was to determine activities of pro-/antioxidant enzymes, reactive oxygen species (ROS) content, and oxidative modification of proteins and lipids in red blood cells (RBCs) and blood plasma of rats exposed to electrostatic field (200 kV/m) during the short (1 h) and the long periods (6 day, 6 h daily). Short-term exposure was characterized by the increase of oxidatively damaged proteins in blood of rats. This was strongly expressed in RBC membranes. After long-term action, RBC content in peripheral blood was higher than in control ( P < 0.01) and the attenuation of prooxidant processes was shown.

  10. Paper-based assay for red blood cell antigen typing by the indirect antiglobulin test.

    PubMed

    Yeow, Natasha; McLiesh, Heather; Guan, Liyun; Shen, Wei; Garnier, Gil

    2016-07-01

    A rapid and simple paper-based elution assay for red blood cell antigen typing by the indirect antiglobulin test (IAT) was established. This allows to type blood using IgG antibodies for the important blood groups in which IgM antibodies do not exist. Red blood cells incubated with IgG anti-D were washed with saline and spotted onto the paper assay pre-treated with anti-IgG. The blood spot was eluted with an elution buffer solution in a chromatography tank. Positive samples were identified by the agglutinated and fixed red blood cells on the original spotting area, while red blood cells from negative samples completely eluted away from the spot of origin. Optimum concentrations for both anti-IgG and anti-D were identified to eliminate the washing step after the incubation phase. Based on the no-washing procedure, the critical variables were investigated to establish the optimal conditions for the paper-based assay. Two hundred ten donor blood samples were tested in optimal conditions for the paper test with anti-D and anti-Kell. Positive and negative samples were clearly distinguished. This assay opens up new applications of the IAT on paper including antibody detection and blood donor-recipient crossmatching and extends its uses into non-blood typing applications with IgG antibody-based diagnostics. Graphical abstract A rapid and simple paper-based assay for red blood cell antigen typing by the indirect antiglobulin test.

  11. Method for extending the useful shelf-life of refrigerated red blood cells by flushing with inert gas

    DOEpatents

    Bitensky, M.W.; Yoshida, Tatsuro

    1997-04-29

    A method is disclosed using oxygen removal for extending the useful shelf-life of refrigerated red blood cells. A cost-effective, 4 C storage procedure that preserves red cell quality and prolongs post-transfusion in vivo survival is described. Preservation of adenosine triphosphate levels and reduction in hemolysis and in membrane vesicle production of red blood cells stored at 4 C for prolonged periods of time is achieved by removing oxygen from the red blood cells at the time of storage; in particular, by flushing with an inert gas. Adenosine triphosphate levels of the stored red blood cells are boosted in some samples by addition of ammonium phosphate. 4 figs.

  12. Detection of an ileal cavernous hemangioma by technetium-99m red blood cell imaging

    SciTech Connect

    Holloway, H.; Johnson, J.; Sandler, M.

    1988-01-01

    Patients with arteriovenous malformations of the bowel may have multiple symptoms secondary to chronic blood loss. A case of ileal cavernous hemangioma detected by Tc-99m labeled red blood cell imaging in the absence of active gastrointestinal bleeding is presented.

  13. Flow structures and red blood cell dynamics in arteriole of dilated or constricted cross section.

    PubMed

    Gambaruto, Alberto M

    2016-07-26

    Vessel with 'circular' or 'star-shaped' cross sections are studied, representing respectively dilated or constricted cases where endothelial cells smoothly line or bulge into the lumen. Computational haemodynamics simulations are carried out on idealised periodic arteriole-sized vessels, with red blood cell 'tube' hematocrit value=24%. A further simulation of a single red blood cell serves for comparison purposes. The bulk motion of the red blood cells reproduces well-known effects, including the presence of a cell-free layer and the apparent shear-thinning non-Newtonian rheology. The velocity flow field is analysed in a Lagrangian reference frame, relative to any given red blood cell, hence removing the bulk coaxial motion and highlighting instead the complex secondary flow patterns. An aggregate formation becomes apparent, continuously rearranging and dynamic, brought about by the inter-cellular fluid mechanics interactions and the deformability properties of the cells. The secondary flow field induces a vacillating radial migration of the red blood cells. At different radial locations, the red blood cells express different residence times, orientation and shape. The shear stresses exerted by the flow on the vessel wall are influenced by the motion of red blood cells, despite the presence of the cell-free layer. Spatial (and temporal) variations of wall shear stress patters are observed, especially for the 'circular' vessel. The 'star-shaped' vessel bears considerable stress at the protruding endothelial cell crests, where the stress vectors are coaxially aligned. The bulging endothelial cells hence regularise the transmission of stresses on the vessel wall.

  14. Effect of exercise conditioning on red blood cell volume and erythropoietin concentration in the beagle dog.

    PubMed

    Mägerlein, H U; Heffner, S A; Fedde, M R

    1990-09-01

    To determine if endurance conditioning has a stimulating effect on red blood cell and erythropoietin production, we exercised five beagle dogs on a motor-driven treadmill for 1 hour per day, 5 days per week, for 6 weeks at a speed near their maximal capability. Three additional beagles were kept in cages and served as nonconditioned controls. Endurance conditioning in these dogs produced no increase in red blood cell mass, serum erythropoietin concentration, or any other blood cell index measured. We conclude that this type of exercise conditioning does not produce the necessary stimulus for an increase in erythropoiesis.

  15. Mechanical and electrical properties of red blood cells using optical tweezers

    NASA Astrophysics Data System (ADS)

    Fontes, A.; Barjas Castro, M. L.; Brandão, M. M.; Fernandes, H. P.; Thomaz, A. A.; Huruta, R. R.; Pozzo, L. Y.; Barbosa, L. C.; Costa, F. F.; Saad, S. T. O.; Cesar, C. L.

    2011-04-01

    Optical tweezers are a very sensitive tool, based on photon momentum transfer, for individual, cell by cell, manipulation and measurements, which can be applied to obtain important properties of erythrocytes for clinical and research purposes. Mechanical and electrical properties of erythrocytes are critical parameters for stored cells in transfusion centers, immunohematological tests performed in transfusional routines and in blood diseases. In this work, we showed methods, based on optical tweezers, to study red blood cells and applied them to measure apparent overall elasticity, apparent membrane viscosity, zeta potential, thickness of the double layer of electrical charges and adhesion in red blood cells.

  16. Investigation of red blood cell antigens with highly fluorescent and stable semiconductor quantum dots.

    PubMed

    de Farias, Patrícia Maria Albuquerque; Santos, Beate Saegesser; de Menezes, Frederico Duarte; de Carvalho Ferreira, Ricardo; Barjas-Castro, Maria Lourdes; Castro, Vagner; Lima, Paulo Roberto Moura; Fontes, Adriana; Cesar, Carlos Lenz

    2005-01-01

    We report a new methodology for red blood cell antigen expression determination by a simple labeling procedure employing luminescent semiconductor quantum dots. Highly luminescent and stable core shell cadmium sulfide/cadmium hydroxide colloidal particles are obtained, with a predominant size of 9 nm. The core-shell quantum dots are functionalized with glutaraldehyde and conjugated to a monoclonal anti-A antibody to target antigen-A in red blood cell membranes. Erythrocyte samples of blood groups A+, A2+, and O+ are used for this purpose. Confocal microscopy images show that after 30 min of conjugation time, type A+ and A2+ erythrocytes present bright emission, whereas the O+ group cells show no emission. Fluorescence intensity maps show different antigen expressions for the distinct erythrocyte types. The results obtained strongly suggest that this simple labeling procedure may be employed as an efficient tool to investigate quantitatively the distribution and expression of antigens in red blood cell membranes.

  17. Clinical evaluation of a /sup 51/Cr-labeled red blood cell survival test for in vivo blood compatibility testing

    SciTech Connect

    Pineda, A.A.; Dharkar, D.D.; Wahner, H.W.

    1984-01-01

    Modified red blood cell survival studies with use of 51Cr were performed in three groups of subjects. Group 1 consisted of normal subjects who were given labeled autologous blood, group 2 were subjects in need of blood transfusions and given labeled ABO and Rh crossmatch-compatible blood, and group 3 were patients in need of blood transfusion but in whom problems arose in finding compatible blood. The results of the studies suggest that for patients with blood compatibility problems, normal red blood cell survival values at 1 hour do not exclude the possibility of severe hemolysis 24 hours later. Thus, if a 1-hour test result is normal, the procedure should be extended routinely to 24 hours. Moreover, the test can be used to evaluate the clinical importance of antibodies. We showed that anti-Yka and anti-Lan were clinically significant, but high-titer, low-avidity antibodies, anti-Kna, anti-I, and anti-HI were clinically insignificant in the cases studied. This finding emphasizes the importance of an in vivo test for the final compatibility evaluation in complicated blood replacement problems.

  18. The Effect of Pulsatile Versus Nonpulsatile Blood Flow on Viscoelasticity and Red Blood Cell Aggregation in Extracorporeal Circulation

    PubMed Central

    Ahn, Chi Bum; Kang, Yang Jun; Kim, Myoung Gon; Yang, Sung; Lim, Choon Hak; Son, Ho Sung; Kim, Ji Sung; Lee, So Young; Son, Kuk Hui; Sun, Kyung

    2016-01-01

    Background Extracorporeal circulation (ECC) can induce alterations in blood viscoelasticity and cause red blood cell (RBC) aggregation. In this study, the authors evaluated the effects of pump flow pulsatility on blood viscoelasticity and RBC aggregation. Methods Mongrel dogs were randomly assigned to two groups: a nonpulsatile pump group (n=6) or a pulsatile pump group (n=6). After ECC was started at a pump flow rate of 80 mL/kg/min, cardiac fibrillation was induced. Blood sampling was performed before and at 1, 2, and 3 hours after ECC commencement. To eliminate bias induced by hematocrit and plasma, all blood samples were adjusted to a hematocrit of 45% using baseline plasma. Blood viscoelasticity, plasma viscosity, hematocrit, arterial blood gas analysis, central venous O2 saturation, and lactate were measured. Results The blood viscosity and aggregation index decreased abruptly 1 hour after ECC and then remained low during ECC in both groups, but blood elasticity did not change during ECC. Blood viscosity, blood elasticity, plasma viscosity, and the aggregation index were not significantly different in the groups at any time. Hematocrit decreased abruptly 1 hour after ECC in both groups due to dilution by the priming solution used. Conclusion After ECC, blood viscoelasticity and RBC aggregation were not different in the pulsatile and nonpulsatile groups in the adult dog model. Furthermore, pulsatile flow did not have a more harmful effect on blood viscoelasticity or RBC aggregation than nonpulsatile flow. PMID:27298790

  19. Transfusion of fresher versus older red blood cells for all conditions.

    PubMed

    Brunskill, Susan J; Wilkinson, Kirstin L; Doree, Carolyn; Trivella, Marialena; Stanworth, Simon

    2015-05-12

    Red blood cell transfusion is a common treatment for anaemia in many clinical conditions. One current concern is uncertainty as to the clinical consequences (notably efficacy and safety) of transfusing red blood cell units that have been stored for different durations of time before a transfusion. If evidence from randomised controlled trials were to indicate that clinical outcomes are affected by storage age, the implications for inventory management and clinical practice would be significant. To assess the effects of using fresher versus older red blood cells in people requiring a red blood cell transfusion. We ran the search on 29th September 2014. We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE (OvidSP), Embase (OvidSP), CINAHL (EBSCO), PubMed (for e-publications), three other databases and trial registers. We included randomised controlled trials comparing fresher red blood cell transfusion versus active transfusion of older red blood cells, and comparing fresher red blood cell transfusion versus current standard practice. All definitions of 'fresher' and 'older'/'standard practice' red blood cells were included. Two review authors independently assessed trial quality and extracted from the trial report data on adverse red blood cell transfusion reactions, when reported. We included 16 trials (1864 participants) in the review. Eight trials (279 participants) compared transfusion of fresher red blood cells versus transfusion of older stored red blood cells ('fresher' vs 'older'). Eight trials (1585 participants) compared the transfusion of fresher red blood cells versus current standard practice ('fresher' vs 'standard practice'). Five trials enrolled neonates, one trial enrolled children and 12 trials enrolled adults. Overall sample sizes were small: only two trials randomly assigned more than 100 participants.We performed no meta-analyses for a variety of reasons: no uniform definition of 'fresher' or 'older' red blood cell

  20. Implementing mass-scale red cell genotyping at a blood center.

    PubMed

    Flegel, Willy A; Gottschall, Jerome L; Denomme, Gregory A

    2015-11-01

    When problems with compatibility beyond ABO and D arise, currently transfusion services search their inventories and perform time-consuming serologic testing to locate antigen-negative blood. These clinically important blood group antigens can be detected reliably by red cell genotyping, which is a technology whereby DNA-based techniques are used to evaluate gene polymorphisms that determine the expression of blood group antigens. We introduced mass-scale genotyping and measured availability of genotyped blood. All non-Caucasian donors qualified for genotyping along with donors who had a history of repeat donation. Mass-scale red cell genotyping, performed on an electronic interfaced open array platform, was implemented to screen blood donors for 32 single-nucleotide polymorphisms that predicted 42 blood group antigens. Genotype screening results were confirmed by phenotyping, when needed for antigen-negative transfusion, before release of the red blood cell (RBC) unit. Approximately 22,000 donors were red cell genotyped within 4 months and a total of 43,066 donors in 4 years. There were 463 discordances (0.52% of 89,596 genotypes with a phenotype). Among the 307 resolved discordances, approximate equal numbers represented historical serologic or genotyping discrepancies (n = 151 and n = 156, respectively). In the final year of the study, a mean of 29% of the daily inventory had a genotype. Red cell genotyping of blood donors using an electronic interface created a large and stable supply of RBC units with historical genotypes. The database served the needs of antigen-negative blood requests for a large regional blood center and allowed us to abandon screening by serology. © 2015 AABB.

  1. Iron balance in the red blood cell donor.

    PubMed

    Brittenham, G M

    2005-01-01

    Phlebotomy of a unit of blood produces a loss of 200 to 250 mg of iron in haemoglobin. Because of physiological differences in iron balance between women of childbearing age and men, the loss of similar amounts of iron at donation has divergent consequences for committed donors. Women of childbearing age have an increased risk of iron deficiency if they donate more than one unit per year while men are usually able to maintain iron balance while donating four or more units of blood per year. Lack of iron is the most important medical reason for deferral from repeat donation and primarily affects women of childbearing age. Deferral of these women discourages them from further donation and may lead to their loss as donors. Provisions for blood donation should protect those who give blood from adverse consequences of their altruism. Safe and effective approaches to iron replacement after donation have been developed that can prevent iron deficiency in women who give blood repeatedly. Blood centres should consider incorporating programmes of iron replacement for women of childbearing age who give blood repeatedly to protect these donors against iron deficiency and to enhance their retention and commitment as dedicated donors.

  2. [Effect of astaxanthin on oxidative stress of red blood cells and peroxidation damage of membrane].

    PubMed

    Wang, Su-Ling; He, Lu-Jun; He, Tian-Bo; Han, Wei; Wang, Qie

    2015-04-01

    To explore the effect of astaxanthin (ASTA) on oxidative stress of intra- and extra- red blood cells during stored period and the protective function for cell membrane. The blood of volunteers was collected to prepare suspended red blood cells without leukocytes. Then the red blood cells were randomly divided into group A, group B, group C and group D. The ASTA was added into MAP preservation solution of group B, group C and group D, the final concentration of ASTA was 5, 10 and 20 µmol/L respectively. Group A was used as control group, in which only the dissolved liquid DMSO of ASTA was added. The red blood cells were stored in refrigerator at 2 °C-6 °C. On day 7, 14, 28 and day 42 of storage, the content of reactive oxygen species (ROS) in red blood cells was detected by fluorescence microplate reader. The content of malondialdehyde (MDA) was detected with TBA method. The content of hydrogen peroxide (H2O2) outside cell was detected with spectrophotometric method. The mean corpuscular volume(MCV) was detected with blood cell analyzer. The content of free hemoglobin(FHb) was detected with chemical colorimetry. The ROS, MDA, FHb and H2O2 levels in B, C and D groups were lower than those in control group during the stored period. On day 7 and 14 of storage, among group B, group C, group D and group A, the MCV showed no difference in comparison with control group. On day 28 and 42 of storage, the MCV in B, C and D groups was lower than that in control group. The ASTA can reduce the oxidative stress level of stored red blood cells inside and outside, relieve the peroxidation damage of cell membrane.

  3. Patterns of Nonelectrolyte Permeability in Human Red Blood Cell Membrane

    PubMed Central

    Naccache, P.; Sha'afi, R. I.

    1973-01-01

    The permeability of human red cell membrane to 90 different molecules has been measured. These solutes cover a wide spectrum of nonelectrolytes with varying chemical structure, chain length, lipid solubility, chemical reactive group, ability to form hydrogen bonds, and other properties. In general, the present study suggests that the permeability of red cell membrane to a large solute is determined by lipid solubility, its molecular size, and its hydrogen-bonding ability. The permeability coefficient increases with increasing lipid solubility and decreasing ability to form hydrogen bonds, whereas it decreases with increasing molecular size. In the case of small solutes, the predominant diffusion factor is steric hindrance augmented by lipid solubility. It is also found that replacement of a hydroxyl group by a carbonyl group or an ether linkage tends to increase permeability. On the other hand, replacement of a hydroxyl group by an amide group tends to decrease the permeability coefficient. PMID:4804758

  4. Proteomics of the red blood cell carbonylome during blood banking of erythrocyte concentrates.

    PubMed

    Delobel, Julien; Prudent, Michel; Tissot, Jean-Daniel; Lion, Niels

    2016-03-01

    Transfusion of red blood cells (RBCs) is a daily medical procedure. Erythrocyte concentrates (ECs) can be stored up to 56 days at 4 °C in saline additive solution mainly composed of adenine and sugar. Such nonphysiological conditions induce the occurrence of storage lesions, such as alterations of metabolism, protein oxidation, and deterioration of rheological properties. Their accumulation tends to decrease the main EC therapeutic property, that is, the oxygenation capacity. Protein carbonylation is a marker of oxidative stress and aging, and its occurrence during RBC storage was earlier characterized as a time-dependent and cellular compartment dependent modification. Three ECs from independent donations were followed. The carbolynome was here characterized in soluble and membrane extracts (n-dodecyl β-D-maltoside-based extraction buffer) of RBCs stored for 6, 27, and 41 days, through biotin hydrazide derivatization, biotin-avidin affinity purification, SDS-PAGE separation, and LC-MS/MS analyses. A total of 142 and 20 proteins were identified as carbonylated in soluble and membrane extracts, respectively. Particularly, a time-dependent evolution of 26.8% of the soluble carbonylome was observed. Affected cellular mechanisms involve antioxidant defenses, metabolism pathways, and proteasomal degradation. To better store RBCs those functions have to be preserved, which opens new routes of investigation in transfusion medicine. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Where do Trypanosoma cruzi go? The distribution of parasites in blood components from fractionated infected whole blood.

    PubMed

    Cancino-Faure, Beatriz; Fisa, Roser; Riera, Cristina; Girona-Llobera, Enrique; Jimenez-Marco, Teresa

    2016-09-01

    Platelets (PLTs) are the blood component most frequently involved in Trypanosoma cruzi transfusion transmission cases reported in the literature, although whole blood (WB) and red blood cells (RBCs) have also been incriminated. However, there is little knowledge of the parasite distribution among blood components. The aim of this study was to investigate in which blood component T. cruzi parasites concentrate the most, after fractionating artificially T. cruzi-infected WB. The T. cruzi parasite load was studied by a specific quantitative real-time polymerase chain reaction (qPCR) in WB, buffy coat (BC), PLT concentrates, RBCs before and after leukoreduction, and plasma (PL). The parasite load in WB experimentally infected with 1.5 × 10(6) parasites (2.78 × 10(3) parasite equivalents/mL) was unevenly distributed among the separated blood components. The highest level was found in the BC (6.94 × 10(3) parasite equivalents/mL) and RBCs before leukoreduction by filtration (2.51 × 10(3) parasite equivalents/mL), after which RBCs presented a 99.9% reduction in parasite levels. Both PL and PLTs, partially leukoreduced by centrifugation but nonfiltered, had low parasite levels, the lowest concentration being in PL. The highest parasite concentration was detected in the BC, followed by RBCs before leukoreduction. There is a notable risk of transfusion-transmitted Chagas disease associated with nonleukoreduced RBCs. Leukoreduction may be an effective prevention strategy for transfusion-transmitted T. cruzi infection, especially in endemic countries and in nonendemic countries with a high rate of immigration from Latin America. © 2016 AABB.

  6. Interaction of red blood cells adjacent to and within a thrombus in experimental cerebral ischaemia.

    PubMed

    van der Spuy, Wendy J; Pretorius, Etheresia

    2013-01-01

    Cerebral ischaemia is associated with altered platelet and fibrin network ultrastructure indicating increased coagulation activity and resistance to fibrinolysis; which may lead to the occlusion of blood vessels. Recently, it has been shown that the addition of red blood cells to plasma has a significant effect on the structural and mechanical properties of fibrin clots and is associated with lytic resistance of thrombi. Whole blood was collected from pre-ischaemic control Sprague Dawley rats and those in which experimental cerebral ischaemia was induced by hyperglycaemic two-vessel occlusion, for the ultrastructural investigation of whole blood thrombi by scanning electron microscopy. Post-ischaemic groups were terminated at 2h, 24h and 48h subsequent to reperfusion; which were time points selected for the demonstration of initial inflammation upon neural injury, maximal neural injury and onset of regeneration. Subsequent to ischaemic insult, red blood cells transformed from normal discoid shape to form projections which allowed them to interact both with each other and with fibrin fibres in various manners. Researches have in recent years shown that inclusion of red blood cells in experimental coagula results in delayed fibrinolysis and lytic resistance. This paper shows the morphological alterations at cellular level which may elucidate the structural and mechanical strength of these clots. Through the extension of projections, red blood cells become intertwined within a thrombus to stabilise and strengthen its structure. The tighter these mechanical bonds, the more resistant thrombi are to lysis, an established characteristic of thrombi in cerebral ischaemia. © 2013.

  7. Storage and survival of red blood cells with elevated sodium levels.

    PubMed

    Wallas, C H; Harris, A S; Wetherall, N T

    1982-01-01

    Approximately 25 percent of black blood donors have an elevated red blood cell (RBC) sodium (Nai) level compared with white donors. This elevation results in a significant increase in the mean Nai from black (9.00 +/- 2.96 mmoles/l RBC) as compared to white blood donors (7.04 +/- 1.48 mmoles/l RBC, p less than 0.001). Red blood cells from four black donors with mean Nai levels of 15 +/- 2.8 mmoles/l RBC were stored for 35 days in citrate-phosphate-dextrose-adenine and compared to that of four donors with normal levels of Nai. Serial measurements of red blood cell adenosine triphosphate, diphosphoglycerate, glucose-6-phosphate dehydrogenase, pyruvic kinase, lactate production rates, and intracellular cations showed no differences between the two donor groups. Furthermore, the mean 24-hour posttransfusion survival was not significantly different for the high Nai group (83.2 +/- 5.6%) as compared with the control group (82.3 +/- 6.9%). Based on this study, it is not necessary to eliminate individuals with an elevated red blood cell Nai level as blood donors.

  8. Nucleated red blood cells, critical illness survivors and postdischarge outcomes: a cohort study.

    PubMed

    Purtle, Steven W; Horkan, Clare M; Moromizato, Takuhiro; Gibbons, Fiona K; Christopher, Kenneth B

    2017-06-21

    Little is known about risk factors associated with out-of-hospital outcomes in survivors of critical illness. We hypothesized that the presence of nucleated red blood cells in patients who survived critical care would be associated with adverse outcomes following hospital discharge. We performed a two-center observational cohort study of patients treated in medical and surgical intensive care units in Boston, Massachusetts. All data were obtained from the Research Patient Data Registry at Partners HealthCare. We studied 2878 patients, age ≥ 18 years, who received critical care between 2011 and 2015 and survived hospitalization. The exposure of interest was nucleated red blood cells occurring from 2 days prior to 7 days after critical care initiation. The primary outcome was mortality in the 90 days following hospital discharge. Secondary outcome was unplanned 30-day hospital readmission. Adjusted odds ratios were estimated by multivariable logistic regression models with inclusion of covariate terms thought to plausibly interact with both nucleated red blood cells and outcome. Adjustment included age, race (white versus nonwhite), gender, Deyo-Charlson Index, patient type (medical versus surgical), sepsis and acute organ failure. In patients who received critical care and survived hospitalization, the absolute risk of 90-day postdischarge mortality was 5.9%, 11.7%, 15.8% and 21.9% in patients with 0/μl, 1-100/μl, 101-200/μl and more than 200/μl nucleated red blood cells respectively. Nucleated red blood cells were a robust predictor of postdischarge mortality and remained so following multivariable adjustment. The fully adjusted odds of 90-day postdischarge mortality in patients with 1-100/μl, 101-200/μl and more than 200/μl nucleated red blood cells were 1.77 (95% CI, 1.23-2.54), 2.51 (95% CI, 1.36-4.62) and 3.72 (95% CI, 2.16-6.39) respectively, relative to patients without nucleated red blood cells. Further, the presence of nucleated red blood

  9. Seventy-five genetic loci influencing the human red blood cell

    PubMed Central

    van der Harst, Pim; Zhang, Weihua; Leach, Irene Mateo; Rendon, Augusto; Verweij, Niek; Sehmi, Joban; Paul, Dirk S.; Elling, Ulrich; Allayee, Hooman; Li, Xinzhong; Radhakrishnan, Aparna; Tan, Sian-Tsung; Voss, Katrin; Weichenberger, Christian X.; Albers, Cornelis A.; Al-Hussani, Abtehale; Asselbergs, Folkert W.; Ciullo, Marina; Danjou, Fabrice; Dina, Christian; Esko, Tõnu; Evans, David M.; Franke, Lude; Gögele, Martin; Hartiala, Jaana; Hersch, Micha; Holm, Hilma; Hottenga, Jouke-Jan; Kanoni, Stavroula; Kleber, Marcus E.; Lagou, Vasiliki; Langenberg, Claudia; Lopez, Lorna M.; Lyytikäinen, Leo-Pekka; Melander, Olle; Murgia, Federico; Nolte, Ilja M.; O’Reilly, Paul F.; Padmanabhan, Sandosh; Parsa, Afshin; Pirastu, Nicola; Porcu, Eleonora; Portas, Laura; Prokopenko, Inga; Ried, Janina S.; Shin, So-Youn; Tang, Clara S.; Teumer, Alexander; Traglia, Michela; Ulivi, Sheila; Westra, Harm-Jan; Yang, Jian; Zhao, Jing Hua; Anni, Franco; Abdellaoui, Abdel; Attwood, Antony; Balkau, Beverley; Bandinelli, Stefania; Bastardot, François; Benyamin, Beben; Boehm, Bernhard O.; Cookson, William O.; Das, Debashish; de Bakker, Paul I. W.; de Boer, Rudolf A.; de Geus, Eco J. C.; de Moor, Marleen H.; Dimitriou, Maria; Domingues, Francisco S.; Döring, Angela; Engström, Gunnar; Eyjolfsson, Gudmundur Ingi; Ferrucci, Luigi; Fischer, Krista; Galanello, Renzo; Garner, Stephen F.; Genser, Bernd; Gibson, Quince D.; Girotto, Giorgia; Gudbjartsson, Daniel Fannar; Harris, Sarah E.; Hartikainen, Anna-Liisa; Hastie, Claire E.; Hedblad, Bo; Illig, Thomas; Jolley, Jennifer; Kähönen, Mika; Kema, Ido P.; Kemp, John P.; Liang, Liming; Lloyd-Jones, Heather; Loos, Ruth J. F.; Meacham, Stuart; Medland, Sarah E.; Meisinger, Christa; Memari, Yasin; Mihailov, Evelin; Miller, Kathy; Moffatt, Miriam F.; Nauck, Matthias; Novatchkova, Maria; Nutile, Teresa; Olafsson, Isleifur; Onundarson, Pall T.; Parracciani, Debora; Penninx, Brenda W.; Perseu, Lucia; Piga, Antonio; Pistis, Giorgio; Pouta, Anneli; Puc, Ursula; Raitakari, Olli; Ring, Susan M.; Robino, Antonietta; Ruggiero, Daniela; Ruokonen, Aimo; Saint-Pierre, Aude; Sala, Cinzia; Salumets, Andres; Sambrook, Jennifer; Schepers, Hein; Schmidt, Carsten Oliver; Silljé, Herman H. W.; Sladek, Rob; Smit, Johannes H.; Starr, John M.; Stephens, Jonathan; Sulem, Patrick; Tanaka, Toshiko; Thorsteinsdottir, Unnur; Tragante, Vinicius; van Gilst, Wiek H.; van Pelt, L. Joost; van Veldhuisen, Dirk J.; Völker, Uwe; Whitfield, John B.; Willemsen, Gonneke; Winkelmann, Bernhard R.; Wirnsberger, Gerald; Algra, Ale; Cucca, Francesco; d’Adamo, Adamo Pio; Danesh, John; Deary, Ian J.; Dominiczak, Anna F.; Elliott, Paul; Fortina, Paolo; Froguel, Philippe; Gasparini, Paolo; Greinacher, Andreas; Hazen, Stanley L.; Jarvelin, Marjo-Riitta; Khaw, Kay Tee; Lehtimäki, Terho; Maerz, Winfried; Martin, Nicholas G.; Metspalu, Andres; Mitchell, Braxton D.; Montgomery, Grant W.; Moore, Carmel; Navis, Gerjan; Pirastu, Mario; Pramstaller, Peter P.; Ramirez-Solis, Ramiro; Schadt, Eric; Scott, James; Shuldiner, Alan R.; Smith, George Davey; Smith, J. Gustav; Snieder, Harold; Sorice, Rossella; Spector, Tim D.; Stefansson, Kari; Stumvoll, Michael; Wilson Tang, W. H.; Toniolo, Daniela; Tönjes, Anke; Visscher, Peter M.; Vollenweider, Peter; Wareham, Nicholas J.; Wolffenbuttel, Bruce H. R.; Boomsma, Dorret I.; Beckmann, Jacques S.; Dedoussis, George V.; Deloukas, Panos; Ferreira, Manuel A.; Sanna, Serena; Uda, Manuela; Hicks, Andrew A.; Penninger, Josef Martin; Gieger, Christian; Kooner, Jaspal S.; Ouwehand, Willem H.; Soranzo, Nicole; Chambers, John C

    2013-01-01

    Anaemia is a chief determinant of globalill health, contributing to cognitive impairment, growth retardation and impaired physical capacity. To understand further the genetic factors influencing red blood cells, we carried out a genome-wide association study of haemoglobin concentration and related parameters in up to 135,367 individuals. Here we identify 75 independent genetic loci associated with one or more red blood cell phenotypes at P <10−8, which together explain 4–9% of the phenotypic variance per trait. Using expression quantitative trait loci and bioinformatic strategies, we identify 121 candidate genes enriched in functions relevant to red blood cell biology. The candidate genes are expressed preferentially in red blood cell precursors, and 43 have haematopoietic phenotypes in Mus musculus or Drosophila melanogaster. Through open-chromatin and coding-variant analyses we identify potential causal genetic variants at 41 loci. Our findings provide extensive new insights into genetic mechanisms and biological pathways controlling red blood cell formation and function. PMID:23222517

  10. Nitric oxide synthetic pathway in red blood cells is impaired in coronary artery disease.

    PubMed

    Eligini, Sonia; Porro, Benedetta; Lualdi, Alessandro; Squellerio, Isabella; Veglia, Fabrizio; Chiorino, Elisa; Crisci, Mauro; Garlaschè, Anna; Giovannardi, Marta; Werba, Josè-Pablo; Tremoli, Elena; Cavalca, Viviana

    2013-01-01

    All the enzymatic factors/cofactors involved in nitric oxide (NO) metabolism have been recently found in red blood cells. Increased oxidative stress impairs NO bioavailability and has been described in plasma of coronary artery disease (CAD) patients. The aim of the study was to highlight a potential dysfunction of the metabolic profile of NO in red blood cells and in plasma from CAD patients compared with healthy controls. We determined L-arginine/NO pathway by liquid-chromatography tandem mass spectrometry and high performance liquid chromatography methods. The ratio of oxidized and reduced forms of glutathione, as index of oxidative stress, was measured by liquid-chromatography tandem mass spectrometry method. NO synthase expression and activity were evaluated by immunofluorescence staining and ex-vivo experiments of L-[(15)N2]arginine conversion to L-[(15)N]citrulline respectively. Increased amounts of asymmetric and symmetric dimethylarginines were found both in red blood cells and in plasma of CAD patients in respect to controls. Interestingly NO synthase expression and activity were reduced in CAD red blood cells. In contrast, oxidized/reduced glutathione ratio was increased in CAD and was associated to arginase activity. Our study analyzed for the first time the whole metabolic pathway of L-arginine/NO, both in red blood cells and in plasma, highlighting an impairment of NO pathway in erythrocytes from CAD patients, associated with decreased NO synthase expression/activity and increased oxidative stress.

  11. Analysis of Hereditary Elliptocytosis with Decreased Binding of Eosin-5-maleimide to Red Blood Cells.

    PubMed

    Suemori, Shin-ichiro; Wada, Hideho; Nakanishi, Hidekazu; Tsujioka, Takayuki; Sugihara, Takashi; Tohyama, Kaoru

    2015-01-01

    Flow cytometric test for analyzing the eosin-5-maleimide (EMA) binding to red blood cells has been believed to be a specific method for diagnosing hereditary spherocytosis (HS). However, it has been reported that diseases other than HS, such as hereditary pyropoikilocytosis (HPP) and Southeast Asian ovalocytosis (SAO), which are forms in the category of hereditary elliptocytosis (HE), show decreased EMA binding to red blood cells. We analyzed EMA binding to red blood cells in 101 healthy control subjects and 42 HS patients and obtained a mean channel fluorescence (MCF) cut-off value of 36.4 (sensitivity 0.97, specificity 0.95). Using this method, we also analyzed 12 HE patients. Among them, four HE patients showed the MCF at or below the cut-off value. It indicates that some HE patients have decreased EMA binding to red blood cells. Two of these four HE patients were classified as common HE, and two were spherocytic HE with reduced spectrin. This study demonstrates that, in addition to patients with HPP or SAO, some HE patients have decreased EMA binding to red blood cells.

  12. Nitric Oxide Synthetic Pathway in Red Blood Cells Is Impaired in Coronary Artery Disease

    PubMed Central

    Eligini, Sonia; Porro, Benedetta; Lualdi, Alessandro; Squellerio, Isabella; Veglia, Fabrizio; Chiorino, Elisa; Crisci, Mauro; Garlaschè, Anna; Giovannardi, Marta; Werba, Josè-Pablo; Tremoli, Elena; Cavalca, Viviana

    2013-01-01

    Background All the enzymatic factors/cofactors involved in nitric oxide (NO) metabolism have been recently found in red blood cells. Increased oxidative stress impairs NO bioavailability and has been described in plasma of coronary artery disease (CAD) patients. The aim of the study was to highlight a potential dysfunction of the metabolic profile of NO in red blood cells and in plasma from CAD patients compared with healthy controls. Methods We determined L-arginine/NO pathway by liquid-chromatography tandem mass spectrometry and high performance liquid chromatography methods. The ratio of oxidized and reduced forms of glutathione, as index of oxidative stress, was measured by liquid-chromatography tandem mass spectrometry method. NO synthase expression and activity were evaluated by immunofluorescence staining and ex-vivo experiments of L-[15N2]arginine conversion to L-[15N]citrulline respectively. Results Increased amounts of asymmetric and symmetric dimethylarginines were found both in red blood cells and in plasma of CAD patients in respect to controls. Interestingly NO synthase expression and activity were reduced in CAD red blood cells. In contrast, oxidized/reduced glutathione ratio was increased in CAD and was associated to arginase activity. Conclusion Our study analyzed for the first time the whole metabolic pathway of L-arginine/NO, both in red blood cells and in plasma, highlighting an impairment of NO pathway in erythrocytes from CAD patients, associated with decreased NO synthase expression/activity and increased oxidative stress. PMID:23940508

  13. Oxygen therapeutics: pursuit of an alternative to the donor red blood cell.

    PubMed

    Ness, Paul M; Cushing, Melissa M

    2007-05-01

    There is no true substitute for the many functions of human red blood cells, and synthetic products will not replace the need for blood donation in the foreseeable future. Hemoglobin-based oxygen carriers have many characteristics that would serve as a useful adjunct to red cells in clinical settings. Over time, these technologies have the potential to dramatically reshape the practice of transfusion medicine. To review the characteristics and potential utility of hemoglobin-based oxygen carriers and perfluorocarbon-based oxygen carriers. Several hemoglobin-based oxygen carriers are under study in phase III clinical trials. Novel uses for synthetic oxygen therapeutics are emphasized. All published reports with the key words oxygen therapeutics, blood substitutes, and red cell substitutes from 1933 until March 2006 were searched through Medline. Significant findings were synthesized. Recognition of the true impact of red cell substitutes is still several years away. The most compelling products, hemoglobin-based oxygen carriers, have potential use in trauma, providing immediate oxygen-carrying support in the face of alloantibodies or autoantibodies, and in other clinical situations in which long-term survival of red cells is not essential. In the interim, efforts should be focused on enhancing the current blood supply system while supporting ongoing and planned blood substitute research efforts, including trials assessing novel clinical indications for these products.

  14. Label-free optical sensor based on red blood cells laser tweezers Raman spectroscopy analysis for ABO blood typing.

    PubMed

    Lin, Duo; Zheng, Zuci; Wang, Qiwen; Huang, Hao; Huang, Zufang; Yu, Yun; Qiu, Sufang; Wen, Cuncheng; Cheng, Min; Feng, Shangyuan

    2016-10-17

    The clinical significance of ABO blood typing extends beyond transfusion medicine and is demonstrated to be associated with susceptibility to various diseases, even including cancer. In this study, a home-made laser tweezers Raman spectroscopy (LTRS) system was applied to detect red blood cells (RBCs) with the aim to develop a label-free, simple and objective blood typing method for the first time. High-quality Raman spectra of RBCs in the fingerprint region of 420-1700 cm-1 can be obtained, meanwhile exciting blood typing results can be achieved, especially with an accuracy of 100% for identifying Type AB from other blood types with the use of multivariate statistical analysis based on principal component analysis (PCA) combined with linear discriminant analysis (LDA). This primary work demonstrates that the label-free RBCs LTRS analysis in conjunction with PCA-LDA diagnostic algorithms has great potential as a biosensor for ABO blood typing.

  15. In vitro red blood cell assay for oxidant toxicity of petroleum oil

    SciTech Connect

    Couillard, C.M.; Leighton, F.A. )

    1993-05-01

    Petroleum oil has caused hemolytic anemia in birds and mammals. In birds, an oxidant damage on circulating red cells has been identified as the primary toxic effect of ingested petroleum oils. An in vitro red blood cell assay was developed to discriminate among the oxidant activities of different petroleum oils. The assay used rabbit red blood cells with a rat liver enzyme system and formation of methemoglobin was measured as an indicator of oxidant damage to the red cells. The assay was applied to five different petroleum oils and to naphthalene, a petroleum hydrocarbon known to cause hemolytic anemia. Different petroleum oils differed in their capacity to induce methemoglobin formation. Methemoglobin levels varied from 2.9% with Arabian light crude oil to 6.2% with South Louisiana crude oil. Naphthalene induced formation of up to 37% methemoglobin. Naphthalene and the five petroleum oils generated methemoglobin only in the presence of liver enzymes.

  16. Shear induced diffusion in a red blood cell suspension

    NASA Astrophysics Data System (ADS)

    Podgorski, Thomas; Grandchamp, Xavier; Srivastav, Aparna; Coupier, Gwennou

    2012-11-01

    In the microcirculation, blood exhibits an inhomogeneous structure which results in the well know Fahraeus-Lindqvist effect : the apparent viscosity decreases when the diameter of the capillary decreases due to the formation of a marginal cell depletion layer (known as plasma skimming). This structure is a consequence of several phenomena, which include i) the migration of cells aways from walls due to lift forces and gradients of shear and ii) shear induced diffusion due to collisions and interactions among cells. We investigated these phenomena through experiments in simple shear and microchannel flows, with dilute suspensions of vesicles and blood cells. Pairwise interactions between suspended objects result in non-linear and flow-dependent diffusion, whose properties have been measured in different experiments for vesicles and blood cells. The injection of a sheet of concentrated blood cell suspension in a microchannel with a rectangular cross-section allows, through the measurement of its widening along the channel, to measure the diffusivity of blood cells, both in the local plane of shear and in the vorticity direction.

  17. Altered red blood cell surface area in hereditary xerocytosis.

    PubMed

    Sauberman, N; Fairbanks, G; Lutz, H U; Fortier, N L; Snyder, L M

    1981-08-10

    Hereditary xerocytes appear larger than normal red cells in scanning electron micrographs and exhibit a higher ghost packing volume. The major chemical components--protein, phosphorus, cholesterol and sialic acid--are increased uniformly, as are all polypeptides visible on gel electrophoresis patterns of xerocyte membranes. These data are consistent with a xerocyte surface area 15 to 25% above normal. Certain clinical anomalies common to this disorder, including unexpectedly low reticulocyte count and 2,3-diphosphoglycerate level, are discussed in the light of the present findings.

  18. Storage time of red blood cells and mortality of transfusion recipients.

    PubMed

    Middelburg, Rutger A; van de Watering, Leo M G; Briët, Ernest; van der Bom, Johanna G

    2013-01-01

    Storage of red cells and the associated storage lesion have been suggested to contribute to adverse clinical outcomes. The aim of this study was to investigate whether increasing storage time of red cells is associated with mortality of recipients. From all patients who received red cell transfusions between January 2005 and May 2009, in the Leiden University Medical Center, we selected those who received only-young or only-old red cells, defined as below or above the median storage time. Mortality was compared in a Cox regression model. Subsequently, similar comparisons were made between subgroups with increasing contrast between old and young red cells. Among adult patients, after correction for potential confounders, the hazard ratio of death within 1 year after receiving red cells stored for more than 17 days compared with 17 days or less was 0.98 (95% confidence interval, 0.83-1.2). With increasing contrast, the hazard ratio decreased to 0.56 (95% confidence interval, 0.32-0.97) for red cells stored for more than 24 days compared with less than 10 days. In contrast to what has previously been suggested, we find an almost 2-fold increase in mortality rate after the transfusion of fresh red cells compared with old red cells. Results dependent on analyses chosen and previous studies may not have used optimal analyses. The tendency to demand ever-fresher blood could actually be detrimental for at least some patient groups.

  19. [Red blood of cosmonauts on missions aboard the International Space Station (ISS)].

    PubMed

    Ivanova, S M; Morukov, B V; Labetskaia, O I; Iarlykova, Iu V; Levina, A A; Shishkanova, Z G

    2007-01-01

    Morphobiochemical investigations of red blood (space experiment Hematologiya) involved the ISS Russian crew members (increments 6-12). Blood samples were drawn on L-30, at the beginning (FD 6-10) and end (FD 160-190) of orbital flight, shortly after landing (R+0), and on R+7 and R+15. Results of the investigations of red blood metabolism and cell membrane showed that long-duration space flight reduces the hemoglobin level in consequence of, probably, intensive erythropoiesis and premature partial elimination of degraded (possibly old) erythrocytes from circulating blood. High intensity of erythropoises is manifested by an increase in erythropoietin, a decrease in blood iron, and elimination of degraded and old erythrocytes in the course of readaptation to Earth and driven by the growing body demand for oxygen to support muscular work and existence in the gravitational environment in general.

  20. [Development and challenge of modified hemoglobins as red blood cell substitutes].

    PubMed

    Lu, Xiu-Ling

    2006-01-01

    The problems of blood shortage and the virus infection risk of blood transfusion have promoted the study of blood substitutes. Modified hemoglobin has become the focus of the challenges research because of its excellent oxygen carrying ability. To overcome the toxicity effect on direct use of purified native hemoglobin, various modification technologies have been developed, including diaspirin cross-linking, glutaraldehyde polymerization, O-raffinose polymerization, polyethylene glycol conjugation, liposome encapsulation and biodegradable polymer encapsulation. Some of the products have been in clinical trials, and one of the products has been approved in a country for clinical use. Research on red blood cell substitutes in China has also developed fast. This paper provides an overview of the history and current status in development of different hemoglobin-based red blood cell substitutes, especially the problems encountered, the challenges faced, and the prospects in future.

  1. Red blood cell: from its mechanics to its motion in shear flow.

    PubMed

    Viallat, A; Abkarian, M

    2014-06-01

    There is a number of publications on red blood cell deformability, that is, on the remarkable cell ability to change its shape in response to an external force and to pass through the narrowest blood capillaries and splenic sinuses. Cell deformability is postulated to be a major determinant of impaired perfusion, increase of blood viscosity, and occlusion in microvessels. Current deformability tests like ektacytometry measure global parameters, related to shape changes at the whole cell scale. Despite strong advances in our understanding of the molecular organization of red blood cells, the relationships between the rheology of each element of the cell composite structure, the global deformability tests, and the cell behavior in microflows are still not elucidated. This review describes recent advances in the description of the dynamics of red blood cells in shear flow and in the mechanistic understanding of this dynamics at the scale of the constitutive rheological and structural elements of the cell. These developments could open up new horizons for the determination of red blood cell mechanical parameters by analyzing their motion under low shear flows.

  2. Acute effects of red wine on cytochrome P450 eicosanoids and blood pressure in men.

    PubMed

    Barden, Anne E; Croft, Kevin D; Beilin, Lawrence J; Phillips, Michael; Ledowski, Thomas; Puddey, Ian B

    2013-11-01

    The vasodilation accompanying acute alcohol ingestion is hard to reconcile with the strong evidence linking chronic alcohol consumption with hypertension. Cytochrome P450 (CYP450) eicosanoids derived from arachidonic acid include vasodilator epoxyeicosatrienoic acids (EETs) and the vasoconstrictor 20-hydroxyeicosatrienoic acid (20-HETE). This study aimed to examine the relationship between CYP450 eicosanoids and blood pressure (BP), and compared the effect of single session of drinking red wine with de-alcoholized red wine (DRW) or water over 24 h. Twenty-five normotensive men were randomly assigned to drink either 375 ml of red wine (41 g of alcohol) or the equivalent volume of DRW or water, with a light meal on 3 separate days. Ambulatory BP and heart rate were measured over 24 h. Blood samples were obtained before and 2, 4 and 24 h after beverage consumption. Blood pressure fell in the first 4 h after red wine consumption (P = 0.001), but was significantly higher after 20 h (P = 0.037). Plasma 20-HETE fell in the 2 h after consumption of all beverages, but over the 24-h period was relatively higher after red wine consumption (P = 0.025). The largest difference in 20-HETE was 2 h after consuming red wine and coincided with the highest blood alcohol level. There were no significant effects of red wine on plasma EETs. Acute consumption of alcohol as red wine results in a relative increase in plasma levels of the vasoconstrictor 20-HETE over 24 h without affecting EETs, and may contribute to the BP elevation that associates with a binge drinking pattern or be a homeostatic response to the acute fall in BP induced by alcohol.

  3. A micro-scale simulation of red blood cell passage through symmetric and asymmetric bifurcated vessels

    PubMed Central

    Wang, Tong; Rongin, Uwitije; Xing, Zhongwen

    2016-01-01

    Blood exhibits a heterogeneous nature of hematocrit, velocity, and effective viscosity in microcapillaries. Microvascular bifurcations have a significant influence on the distribution of the blood cells and blood flow behavior. This paper presents a simulation study performed on the two-dimensional motions and deformation of multiple red blood cells in microvessels with diverging and converging bifurcations. Fluid dynamics and membrane mechanics were incorporated. Effects of cell shape, hematocrit, and deformability of the cell membrane on rheological behavior of the red blood cells and the hemodynamics have been investigated. It was shown that the blood entering the daughter branch with a higher flow rate tended to receive disproportionally more cells. The results also demonstrate that red blood cells in microvessels experienced lateral migration in the parent channel and blunted velocity profiles in both straight section and daughter branches, and this effect was influenced by the shape and the initial position of the cells, the hematocrit, and the membrane deformability. In addition, a cell free region around the tip of the confluence was observed. The simulation results are qualitatively consistent with existing experimental findings. This study may provide fundamental knowledge for a better understanding of hemodynamic behavior of micro-scale blood flow. PMID:26830454

  4. A micro-scale simulation of red blood cell passage through symmetric and asymmetric bifurcated vessels

    NASA Astrophysics Data System (ADS)

    Wang, Tong; Rongin, Uwitije; Xing, Zhongwen

    2016-02-01

    Blood exhibits a heterogeneous nature of hematocrit, velocity, and effective viscosity in microcapillaries. Microvascular bifurcations have a significant influence on the distribution of the blood cells and blood flow behavior. This paper presents a simulation study performed on the two-dimensional motions and deformation of multiple red blood cells in microvessels with diverging and converging bifurcations. Fluid dynamics and membrane mechanics were incorporated. Effects of cell shape, hematocrit, and deformability of the cell membrane on rheological behavior of the red blood cells and the hemodynamics have been investigated. It was shown that the blood entering the daughter branch with a higher flow rate tended to receive disproportionally more cells. The results also demonstrate that red blood cells in microvessels experienced lateral migration in the parent channel and blunted velocity profiles in both straight section and daughter branches, and this effect was influenced by the shape and the initial position of the cells, the hematocrit, and the membrane deformability. In addition, a cell free region around the tip of the confluence was observed. The simulation results are qualitatively consistent with existing experimental findings. This study may provide fundamental knowledge for a better understanding of hemodynamic behavior of micro-scale blood flow.

  5. A micro-scale simulation of red blood cell passage through symmetric and asymmetric bifurcated vessels.

    PubMed

    Wang, Tong; Rongin, Uwitije; Xing, Zhongwen

    2016-02-02

    Blood exhibits a heterogeneous nature of hematocrit, velocity, and effective viscosity in microcapillaries. Microvascular bifurcations have a significant influence on the distribution of the blood cells and blood flow behavior. This paper presents a simulation study performed on the two-dimensional motions and deformation of multiple red blood cells in microvessels with diverging and converging bifurcations. Fluid dynamics and membrane mechanics were incorporated. Effects of cell shape, hematocrit, and deformability of the cell membrane on rheological behavior of the red blood cells and the hemodynamics have been investigated. It was shown that the blood entering the daughter branch with a higher flow rate tended to receive disproportionally more cells. The results also demonstrate that red blood cells in microvessels experienced lateral migration in the parent channel and blunted velocity profiles in both straight section and daughter branches, and this effect was influenced by the shape and the initial position of the cells, the hematocrit, and the membrane deformability. In addition, a cell free region around the tip of the confluence was observed. The simulation results are qualitatively consistent with existing experimental findings. This study may provide fundamental knowledge for a better understanding of hemodynamic behavior of micro-scale blood flow.

  6. Optically-driven red blood cell rotor in linearly polarized laser tweezers

    NASA Astrophysics Data System (ADS)

    Khan, Manas; Mohanty, Samarendra K.; Sood, A. K.

    2005-11-01

    We have constructed a dual trap optical tweezers set-up around an inverted microscope where both the traps can be independently controlled and manipulated in all the three dimensions. Here we report our observations on rotation of red blood cells (RBCs) in a linearly polarized optical trap. Red blood cells deform and become twisted in hypertonic phosphate buffer saline and when trapped, experience an unbalanced radiation pressure force. The torque generated from the unbalanced force causes the trapped RBC to rotate. Addition of Ca^{++} ions in the solution, keeping the osmolarity same, makes the cell membranes stiffer and the cells deform less. Thus the speed of rotation of the red blood cells can be controlled, as less deformation and in turn less asymmetry in shape produces less torque under the radiation pressure resulting in slower rotation at the same laser power.

  7. Screening hypochromism (sieve effect) in red blood cells: a quantitative analysis

    PubMed Central

    Razi Naqvi, K.

    2014-01-01

    Multiwavelength UV-visible spectroscopy, Kramers-Kronig analysis, and several other experimental and theoretical tools have been applied over the last several decades to fathom absorption and scattering of light by suspensions of micron-sized pigmented particles, including red blood cells, but a satisfactory quantitative analysis of the difference between the absorption spectra of suspension of intact and lysed red blood cells is still lacking. It is stressed that such a comparison is meaningful only if the pertinent spectra are free from, or have been corrected for, scattering losses, and it is shown that Duysens’ theory can, whereas that of Vekshin cannot, account satisfactorily for the observed hypochromism of suspensions of red blood cells. PMID:24761307

  8. Ex-vivo expansion of red blood cells: how real for transfusion in humans?

    PubMed

    Migliaccio, Anna Rita; Masselli, Elena; Varricchio, Lilian; Whitsett, Carolyn

    2012-03-01

    Blood transfusion is indispensable for modern medicine. In developed countries, the blood supply is adequate and safe but blood for alloimmunized patients is often unavailable. Concerns are increasing that donations may become inadequate in the future as the population ages prompting a search for alternative transfusion products. Improvements in culture conditions and proof-of-principle studies in animal models have suggested that ex-vivo expanded red cells may represent such a product. Compared to other cell therapies transfusion poses the unique challenge of requiring great cell doses (2.5×10(12) cells vs 10(7) cells). Although production of such cell numbers is theoretically possible, current technologies generate red cells in numbers sufficient only for safety studies. It is conceived that by the time these studies will be completed, technical barriers to mass cell production will have been eliminated making transfusion with ex-vivo generated red cells a reality.

  9. Coarse-Grained Molecular Dynamics Simulation of a Red Blood Cell

    NASA Astrophysics Data System (ADS)

    Jiang, Li-Guo; Wu, Heng-An; Zhou, Xiao-Zhou; Wang, Xiu-Xi

    2010-02-01

    A worm-like chain model based on a spectrin network is employed to study the biomechanics of red blood cells. Coarse-grained molecular dynamics simulations are performed to obtain a stable configuration free of external loadings. We also discuss the influence of two parameters: the average bending modulus and the persistence length. The change in shape of a malaria-infected red blood cell can contribute to the change in its molecular-based structure. As the persistence length of the membrane network in the infected red blood cell decreases, the deformability decreases and the biconcave shape is destroyed. The numerical results are comparable with previously reported experimental results. The coarse-grained model can be used to study the relationship between macro-mechanical properties and molecular-scale structures of cells.

  10. Numerical simulation of red blood cell suspensions behind a moving interface in a capillary

    NASA Astrophysics Data System (ADS)

    Zhao, Shihai; Pan, Tsorng-Whay

    2013-11-01

    Computational modeling and simulation are presented on the motion of red blood cells behind a moving interface in a capillary. The methodology is based on an immersed boundary method and the skeleton structure of the red blood cell (RBC) membrane is modeled as a spring network. The computational domain is moving with either a designated RBC or an interface in an infinitely long two-dimensional channel with an undisturbed flow field in front of the domain. The tanking-treading and the inclination angle of a cell in a simple shear flow are briefly discussed for the validation purpose. We then present the results of the motion of red blood cells behind a moving interface in a capillary, which show that the RBCs with higher velocity than the interface speed form a concentrated slug behind the interface. It is a key mechanism responsible for penetration failure in a capillary behind the meniscus. This work is funded by NSF.

  11. Rare hereditary red blood cell enzymopathies associated with hemolytic anemia - pathophysiology, clinical aspects, and laboratory diagnosis.

    PubMed

    Koralkova, P; van Solinge, W W; van Wijk, R

    2014-06-01

    Hereditary red blood cell enzymopathies are genetic disorders affecting genes encoding red blood cell enzymes. They cause a specific type of anemia designated hereditary nonspherocytic hemolytic anemia (HNSHA). Enzymopathies affect cellular metabolism, which, in the red cell, mainly consists of anaerobic glycolysis, the hexose monophosphate shunt, glutathione metabolism, and nucleotide metabolism. Enzymopathies are commonly associated with normocytic normochromic hemolytic anemia. In contrast to other hereditary red cell disorders such as membrane disorders or hemoglobinopathies, the morphology of the red blood cell shows no specific abnormalities. Diagnosis is based on detection of reduced specific enzyme activity and molecular characterization of the defect on the DNA level. The most common enzyme disorders are deficiencies of glucose-6-phosphate dehydrogenase (G6PD) and pyruvate kinase (PK). However, there are a number of other enzyme disorders, often much less known, causing HNSHA. These disorders are rare and often underdiagnosed, and the purpose of this review. In this brief review, we provide an overview of clinically relevant enzymes, their function in red cell metabolism, and key aspects of laboratory diagnosis.

  12. The NHLBI Retrovirus Epidemiology Donor Studies (REDS and REDS-II): Twenty years of research to advance blood product safety and availability

    PubMed Central

    Kleinman, Steven; King, Melissa R; Busch, Michael P; Murphy, Edward L; Glynn, Simone A.

    2012-01-01

    The Retrovirus Epidemiology Donor Study (REDS), conducted from 1989–2001, and the Retrovirus Epidemiology Donor Study-II (REDS-II), conducted from 2004–2012, were National Heart Lung and Blood Institute (NHLBI) funded multicenter programs focused on improving blood safety and availability in the United States. REDS-II also included international study sites in Brazil and China. The three major research domains of REDS/REDS-II have been infectious disease risk evaluation, blood donation availability, and blood donor characterization. Both programs have made significant contributions to transfusion medicine research methodology by the use of mathematical modeling, large-scale donor surveys, innovative methods of repository sample storage, and establishing an infrastructure that responded to potential emerging blood safety threats such as XMRV. Blood safety studies have included protocols evaluating epidemiologic and/or laboratory aspects of HIV, HTLV I/II, HCV, HBV, WNV, CMV, HHV-8, B19V, malaria, CJD, influenza, and T. cruzi infections. Other analyses have characterized: blood donor demographics, motivations to donate, factors influencing donor return, behavioral risk factors, donors’ perception of the blood donation screening process, and aspects of donor deferral. In REDS-II, two large-scale blood donor protocols examined iron deficiency in donors and the prevalence of leukocyte antibodies. This review describes the major study results from over 150 peer-reviewed articles published by these two REDS programs. In 2011, a new seven year program, the Recipient Epidemiology and Donor Evaluation Study-III (REDS-III), was launched. REDS-III expands beyond donor-based research to include studies of blood transfusion recipients in the hospital setting, and adds a third country, South Africa, to the international program. PMID:22633182

  13. Red wine polyphenols do not lower peripheral or central blood pressure in high normal blood pressure and hypertension.

    PubMed

    Botden, Ilse P G; Draijer, Richard; Westerhof, Berend E; Rutten, Joost H W; Langendonk, Janneke G; Sijbrands, Eric J G; Danser, A H Jan; Zock, Peter L; van den Meiracker, Anton H

    2012-06-01

    Epidemiological data suggest that modest red wine consumption may reduce cardiovascular disease risk. Red wine polyphenols improved human endothelial vascular function and reduced blood pressure (BP) in animal studies, but the results of human intervention studies investigating the effect of red wine polyphenols on BP are inconsistent. The objective was to investigate whether polyphenols extracted from red wine reduce peripheral and central BP in subjects with high-normal BP or grade 1 hypertension. In a double-blind, placebo-controlled three-period crossover trial, we assigned 61 subjects (mean age 61.4 ± 8.4 years) with office systolic BP 135 ± 9 mm Hg and diastolic BP 82 ± 8 mm Hg to dairy drinks containing either placebo, 280 mg red wine polyphenols, or 560 mg red wine polyphenols. After each 4-week intervention period, office and 24-h ambulatory BP measurements, and central hemodynamic measurements derived from continuous finger BP recordings were assessed. Polyphenol treatment did not significantly affect 24-h BP: systolic/diastolic BP was 143 ± 2/84 ± 1 mm Hg after placebo, 143 ± 2/84 ± 1 mm Hg after 280 mg/day of red wine polyphenols, and 142 ± 2/83 ± 1 mm Hg after 560 mg/day. Neither dose of polyphenol treatment changed office or central BP, aortic augmentation index (AIx) or pulse wave reflection index. Intake of red wine polyphenols in two different dosages for 4 weeks did not decrease peripheral or central BP in subjects with a high normal or grade 1 hypertension. Our findings do not support the hypothesis that polyphenols account for the suggested cardiovascular benefits of red wine consumption by lowering BP.

  14. Role Ca(2+) in mechanisms of the red blood cells microrheological changes.

    PubMed

    Muravyov, Alexei; Tikhomirova, Irina

    2012-01-01

    To assess the physiological role of intracellular Ca(2+) in the changes of microrheological red blood cell (RBC) properties (RBC deformability and aggregation), we employed several types of chemicals that can increase and decrease of the intracellular Ca(2+) concentration. The rise of Ca(2+) influx, stimulated by mechanical loading, A23187, thrombin, prostaglandin F(2α) was accompanied by a moderate red cell deformability lowering and an increase of their aggregation. In contrast, Ca(2+) entry blocking into the red cells by verapamil led to a significant RBC aggregation decrease and deformability rise. Similar microrheological changes were observed in the red blood cells treated with phosphodiesterase inhibitors IBMX, vinpocetine, rolipram, pentoxifylline. When forskolin (10 μM), an AC stimulator was added to RBC suspension, the RBC deformability was increased (p <0.05). Somewhat more significant deformability rise appeared after RBC incubation with dB-AMP. Red cell aggregation was significantly decreased under these conditions (p<0.01). On the whole the total data clearly show that the red cell aggregation and deformation changes were connected with an activation of both intracellular signaling pathways: Ca(2+) regulatory mechanism and Gs-protein/adenylyl-cyclase-cAMP system. And the final red cell microrheological regulatory effect is connected with the crosstalk between these systems.

  15. Biochemical storage lesions occurring in nonirradiated and irradiated red blood cells: a brief review.

    PubMed

    Adams, F; Bellairs, G; Bird, A R; Oguntibeju, O O

    2015-01-01

    Red blood cells undergo a series of biochemical fluctuations during 35-42-day storage period at 1°C to 6°C. The sodium/potassium pump is immobilised causing a decrease in intracellular potassium with an increase in cytoplasmic sodium levels, glucose levels decline, and acidosis occurs as a result of low pH levels. The frailty of stored erythrocytes triggers the formation of haemoglobin-containing microparticles and the release of cell-free haemoglobin which may add to transfusion difficulties. Lipid peroxidation, oxidative stress to band 3 structures, and other morphological and structural molecular changes also occur leading to spheroechinocytes and osmotic fragility. These changes that transpire in the red cells during the storage period are referred to as "storage lesions." It is well documented that gamma irradiation exacerbates storage lesions and the reports of increased potassium levels leading to adverse reactions observed in neonates and infants have been of particular concern. There are, however, remarkably few systematic studies comparing the in vitro storage lesions of irradiated and nonirradiated red cell concentrates and it has been suggested that the impact of storage lesions on leucocyte reduced red blood cell concentrate (RBCC) is incomplete. The review examines storage lesions in red blood cells and their adverse effects in reference to blood transfusion.

  16. Quantitative absorption cytometry for measuring red blood cell hemoglobin mass and volume.

    PubMed

    Schonbrun, Ethan; Malka, Roy; Di Caprio, Giuseppe; Schaak, Diane; Higgins, John M

    2014-04-01

    We present an optical system, called the quantitative absorption cytometer (QAC), to measure the volume and hemoglobin mass of red blood cells flowing through a microfluidic channel. In contrast to clinical hematology analyzers, where cells are sphered in order for both volume and hemoglobin to be measured accurately, the QAC measures cells in their normal physiological shape. Human red blood cells are suspended in a refractive index-matching absorbing buffer, driven through a microfluidic channel, and imaged using a transmission light microscope onto a color camera. A red and a blue LED illuminate cells and images at each color are used to independently retrieve cell volume and hemoglobin mass. This system shows good agreement with red blood cell indices retrieved by a clinical hematology analyzer and in fact measures a smaller coefficient of variation of hemoglobin concentration. In addition to cell indices, the QAC returns height and mass maps of each measured cell. These quantitative images are valuable for analyzing the detailed morphology of individual cells as well as statistical outliers found in the data. We also measured red blood cells in hypertonic and hypotonic buffers to quantify the correlation between volume and hemoglobin mass under osmotic stress. Because this method is invariant to cell shape, even extremely nonspherical cells in hypertonic buffers can be measured accurately. © 2014 International Society for Advancement of Cytometry.

  17. Quantitative Absorption Cytometry for Measuring Red Blood Cell Hemoglobin Mass and Volume

    PubMed Central

    Schonbrun, Ethan; Malka, Roy; Di Caprio, Giuseppe; Schaak, Diane; Higgins, John M.

    2015-01-01

    We present an optical system, called the quantitative absorption cytometer (QAC), to measure the volume and hemoglobin mass of red blood cells flowing through a microfluidic channel. In contrast to clinical hematology analyzers, where cells are sphered in order for both volume and hemoglobin to be measured accurately, the QAC measures cells in their normal physiological shape. Human red blood cells are suspended in a refractive index-matching absorbing buffer, driven through a microfluidic channel, and imaged using a transmission light microscope onto a color camera. A red and a blue LED illuminate cells and images at each color are used to independently retrieve cell volume and hemoglobin mass. This system shows good agreement with red blood cell indices retrieved by a clinical hematology analyzer and in fact measures a smaller coefficient of variation of hemoglobin concentration. In addition to cell indices, the QAC returns height and mass maps of each measured cell. These quantitative images are valuable for analyzing the detailed morphology of individual cells as well as statistical outliers found in the data. We also measured red blood cells in hypertonic and hypotonic buffers to quantify the correlation between volume and hemoglobin mass under osmotic stress. Because this method is invariant to cell shape, even extremely nonspherical cells in hypertonic buffers can be measured accurately. PMID:24677669

  18. An effect of glycoprotein IIb/IIIa inhibitors on the kinetics of red blood cells aggregation.

    PubMed

    Sokolova, Irina A; Muravyov, Alexei V; Khokhlova, Maria D; Rikova, Sofya Yu; Lyubin, Evgeny V; Gafarova, Marina A; Skryabina, Maria N; Fedyanin, Angrey A; Kryukova, Darya V; Shahnazarov, Alexander A

    2014-01-01

    The reversible aggregation of red blood cells (RBCs) continues to be of the basic science and clinical interest. Recently it has been reported about a specific binding between fibrinogen and unknown erythrocyte glycoprotein receptors. The aim of this study was to investigate whether the red blood cell aggregation (RBCA) include the cell-cell interaction using the membrane receptors that bind such ligands as fibrinogen or fibronectin. To test this hypothesis the RBCs were incubated with monafram - the drug of the monoclonal antibodies against glycoprotein (GP) IIb/IIIa, with the GPIIb-IIIa receptor antagonist tirofiban, epifibatide and with the fibrinogen inhibiting peptide. It has been found that the RBC incubation with monafram resulted in a marked RBCA decrease mainly in persons with high level of aggregation. Another research session has shown that RBC incubation with fibronectin was accompanied by a significant RBCA rise. The monafram addition to red cell incubation medium resulted in a significant RBCA lowering. The cell incubation with tirofiban and epifibatide issued in RBCA decrease. The similar results were obtained when RBCs were incubated with the fibrinogen inhibiting peptide. Although monafram, tirofiban, eptifibatide and the fibrinogen inhibiting peptide were related to fibrinogen function they didn't inhibit RBCA completely. Therefore, under moderate and low red blood cell aggregation the cell binding is probably related to nonspecific mode. It seems evident that the specific and nonspecific modes of red blood cell aggregate formation could co-exist. Additional theoretical and experimental investigations in this area are needed.

  19. Needleless connectors substantially reduce flow of crystalloid and red blood cells during rapid infusion.

    PubMed

    Lehn, Robert A; Gross, Jeffrey B; McIsaac, Joseph H; Gipson, Keith E

    2015-04-01

    Although needleless connectors (NC) are frequently used in the perioperative setting, the potential of modern NCs to slow delivery of IV fluids has not been thoroughly studied. We examined flow characteristics of 5 NC models during pressurized delivery of crystalloid and banked red blood cells from a Level 1 warmer through various IV catheters. Crystalloid flow rates were reduced by 29% to 85% from control in catheters >18 gauge, while red blood cell flow reductions ranged from 22% to 76% in these catheters (all P < 0.0050). We suggest that practitioners consider eliminating NCs when large IV catheters are inserted for rapid fluid administration.

  20. Mechanical property analysis of stored red blood cell using optical tweezers.

    PubMed

    Li, Yanjie; Wen, Cheng; Xie, Huimin; Ye, Anpei; Yin, Yajun

    2009-05-01

    The deformation of human red blood cells subjected to direct stretching by optical tweezers was analyzed. The maximum force exerted by optical tweezers on the cell via a polystyrene microbead 5microm in diameter was 315pN. Digital image correlation (DIC) method was introduced to calculate the force and the deformation of the cell for the first time. Force-extension relation curves of the biconcave cell were quantitatively assessed when erythrocytes were stored in Alsever's Solution for 2 days, 5 days, 7 days and 14 days respectively. Experiment results demonstrated that the deformability of red blood cells was impaired with the stored time.

  1. Clinical Decision Support Reduces Overuse of Red Blood Cell Transfusions: Interrupted Time Series Analysis.

    PubMed

    Kassakian, Steven Z; Yackel, Thomas R; Deloughery, Thomas; Dorr, David A

    2016-06-01

    Red blood cell transfusion is the most common procedure in hospitalized patients in the US. Growing evidence suggests that a sizeable percentage of these transfusions are inappropriate, putting patients at significant risk and increasing costs to the health care system. We performed a retrospective quasi-experimental study from November 2008 until November 2014 in a 576-bed tertiary care hospital. The intervention consisted of an interruptive clinical decision support alert shown to a provider when a red blood cell transfusion was ordered in a patient whose most recent hematocrit was ≥21%. We used interrupted time series analysis to determine whether our primary outcome of interest, rate of red blood cell transfusion in patients with hematocrit ≥21% per 100 patient (pt) days, was reduced by the implementation of the clinical decision support tool. The rate of platelet transfusions was used as a nonequivalent dependent control variable. A total of 143,000 hospital admissions were included in our analysis. Red blood cell transfusions decreased from 9.4 to 7.8 per 100 pt days after the clinical decision support intervention was implemented. Interrupted time series analysis showed that significant decline of 0.05 (95% confidence interval [CI], 0.03-0.07; P < .001) units of red blood cells transfused per 100 pt days per month was already underway in the preintervention period. This trend accelerated to 0.1 (95% CI, 0.09-0.12; P < .001) units of red blood cells transfused per 100 pt days per month following the implementation of the clinical decision support tool. There was no statistical change in the rate of platelet transfusion resulting from the intervention. The implementation of an evidence-based clinical decision support tool was associated with a significant decline in the overuse of red blood cell transfusion. We believe this intervention could be easily replicated in other hospitals using commercial electronic health records and a similar reduction in

  2. New diffractometric equations and data processing algorithm for laser ektacytometry of red blood cells

    NASA Astrophysics Data System (ADS)

    Nikitin, S. Yu.; Ustinov, V. D.; Yurchuk, Yu. S.; Lugovtsov, A. E.; Lin, M. D.; Priezzhev, A. V.

    2016-07-01

    The problem of measuring the deformability of red blood cells in shear flow by laser diffractometry (ektacytometry) is considered. New diffractometric equations are obtained, which relate the parameters of the diffraction pattern to the characteristics of the erythrocyte ensemble, such as mean deformability as well as width and asymmetry of the erythrocytes distribution in deformability. A feature of these equations is that they include only geometric parameters of the diffraction pattern but do not contain its energy parameters. Basing on these equations, we propose a new data processing algorithm for the laser ektacytometry of red blood cells.

  3. Morphological and biochemical characterization of mitochondria in Torpedo red blood cells.

    PubMed

    Pica, A; Scacco, S; Papa, F; De Nitto, E; Papa, S

    2001-02-01

    A study is presented on the morphology and respiratory functions of mitochondria from Torpedo marmorata red blood cells. In vivo staining of red blood cells and transmission electron microscopy showed the existence of a considerable number of vital and orthodox mitochondria which decreased from young erythroblasts to mature erythrocytes from 60-50 to 30-20 per cell. In erythrocytes mitochondria exhibited a canonical, functional respiratory chain. The content and activity of cytochromes in erythrocytes were, however, significantly lower as compared to mammalian tissues.

  4. [Instant effect of temperature on the oxygen carrying capacity of single living intact red blood cell].

    PubMed

    Yao, Cheng-can; Li, Xiao-kun; Huang, Yao-xiong

    2005-04-01

    The instant effect of temperature on the absorption spectra of the hemoglobin in single living intact red blood cells was investigated, by employing a highly sensitive fast multi-channel micro-spectrophotometer system to perform non-invasive, in situ, real time measurements on the cells. It was found that both the heights and position of the specific peaks in the absorption spectra of intercellular hemoglobin were changed with temperature, indicating that the oxygen carrying capacity of red blood cells varies with temperature. The correlations of the structure and concentration as well as the function of hemoglobin, and the molecular mechanism were also discussed.

  5. Red blood cell glutathione peroxidase activity in female nulligravid and pregnant rats

    PubMed Central

    Gallo, Giuseppe; Martino, Guglielmo

    2009-01-01

    Background The alterations of the glutathione peroxidase enzyme complex system occur in physiological conditions such as aging and oxidative stress consequent to strenuous exercise. Methods Authors optimize the spectrophotometric method to measure glutathione peroxidase activity in rat red blood cell membranes. Results The optimization, when applied to age paired rats, both nulligravid and pregnant, shows that pregnancy induces, at seventeen d of pregnancy, an increase of both reactive oxygen substance concentration in red blood cells and membrane glutathione peroxidase activity. Conclusion The glutathione peroxidase increase in erythrocyte membranes is induced by systemic oxidative stress long lasting rat pregnancy. PMID:19171040

  6. Non-selective voltage-activated cation channel in the human red blood cell membrane.

    PubMed

    Kaestner, L; Bollensdorff, C; Bernhardt, I

    1999-02-04

    Using the patch-clamp technique, a non-selective voltage-activated Na+ and K+ channel in the human red blood cell membrane was found. The channel operates only at positive membrane potentials from about +30 mV (inside positive) onwards. For sodium and potassium ions, similar conductances of about 21 pS were determined. Together with the recently described K+(Na+)/H+ exchanger, this channel is responsible for the increase of residual K+ and Na+ fluxes across the human red blood cell membrane when the cells are suspended in low ionic strength medium.

  7. Small-angle X-ray scattering probe of intermolecular interaction in red blood cells

    NASA Astrophysics Data System (ADS)

    Liu, Guan-Fen; Wang, We-Jia; Xu, Jia-Hua; Dong, Yu-Hui

    2015-03-01

    With high concentrations of hemoglobin (Hb) in red blood cells, self-interactions among these molecules could increase the propensities of their polymerization and aggregation. In the present work, high concentration Hb in solution and red blood cells were analyzed by small-angle X-ray scattering. Calculation of the effective structure factor indicates that the interaction of Hb molecules is the same when they are crowded together in both the cell and physiological saline. The Hb molecules stay individual without the formation of aggregates and clusters in cells. Supported by National Basic Research Program of China (2009CB918600) and National Natural Science Foundation of China (10979005)

  8. Sucralose sweetener in vivo effects on blood constituents radiolabeling, red blood cell morphology and radiopharmaceutical biodistribution in rats.

    PubMed

    Rocha, G S; Pereira, M O; Benarroz, M O; Frydman, J N G; Rocha, V C; Pereira, M J; Fonseca, A S; Medeiros, A C; Bernardo-Filho, M

    2011-01-01

    Effects of sucralose sweetener on blood constituents labelled with technetium-99m ((99m)Tc) on red blood cell (RBC) morphology, sodium pertechnetate (Na(99m)TcO(4)) and diethylenetriaminepentaacetic acid labeled with (99m)Tc ((99m)Tc-DTPA) biodistribution in rats were evaluated. Radiolabeling on blood constituents from Wistar rats was undertaken for determining the activity percentage (%ATI) on blood constituents. RBC morphology was also evaluated. Na(99m)TcO(4) and (99m)Tc-DTPA biodistribution was used to determine %ATI/g in organs. There was no alteration on RBC blood constituents and morphology %ATI. Sucralose sweetener was capable of altering %ATI/g of the radiopharmaceuticals in different organs. These findings are associated to the sucralose sweetener in specific organs.

  9. Biomechanics and biorheology of red blood cells in sickle cell anemia

    PubMed Central

    Li, Xuejin; Dao, Ming; Lykotrafitis, George; Karniadakis, George Em

    2017-01-01

    Sickle cell anemia (SCA) is an inherited blood disorder that causes painful crises due to vaso-occlusion of small blood vessels. The primary cause of the clinical phenotype of SCA is the intracellular polymerization of sickle hemoglobin resulting in sickling of red blood cells (RBCs) in deoxygenated conditions. In this review, we discuss the biomechanical and biorheological characteristics of sickle RBCs and sickle blood as well as their implications toward a better understanding of the pathophysiology and pathogenesis of SCA. Additionally, we highlight the adhesive heterogeneity of RBCs in SCA and their specific contribution to vaso-occlusive crisis. PMID:27876368

  10. Biomechanics and biorheology of red blood cells in sickle cell anemia.

    PubMed

    Li, Xuejin; Dao, Ming; Lykotrafitis, George; Karniadakis, George Em

    2017-01-04

    Sickle cell anemia (SCA) is an inherited blood disorder that causes painful crises due to vaso-occlusion of small blood vessels. The primary cause of the clinical phenotype of SCA is the intracellular polymerization of sickle hemoglobin resulting in sickling of red blood cells (RBCs) in deoxygenated conditions. In this review, we discuss the biomechanical and biorheological characteristics of sickle RBCs and sickle blood as well as their implications toward a better understanding of the pathophysiology and pathogenesis of SCA. Additionally, we highlight the adhesive heterogeneity of RBCs in SCA and their specific contribution to vaso-occlusive crisis. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. An audit on the current practice of red blood cell transfusion following elective primary hip arthroplasty.

    PubMed

    Ozgönenel, Bülent; Kanhere, Rujuta; O'Malley, Barbara; Balasubramaniam, Mamtha; Eisenbrey, A Bradley

    2007-08-01

    This audit encompassing a six-month period on the current practice of red blood cell transfusion following elective primary total hip arthroplasty showed that the rate of allogeneic blood avoidance was 84.8% for preoperative autologous blood donors and 47.8% for non-donors (p<0.001). Lower preoperative hemoglobin level was associated with an increased allogeneic unit transfusion (p<0.001). The intraoperative use of autologous blood collection and transfusion systems did not reduce the transfusion risk, and the use of the colloid volume expander was associated with a 1.8-fold increased risk of transfusion (p=0.022).

  12. Hyperkalemia after irradiation of packed red blood cells: Possible effects with intravascular fetal transfusion

    SciTech Connect

    Thorp, J.A.; Plapp, F.V.; Cohen, G.R.; Yeast, J.D.; O'Kell, R.T.; Stephenson, S. )

    1990-08-01

    Plasma potassium, calcium, and albumin concentrations in irradiated blood, and in fetal blood before and after transfusion, were measured. Dangerously high plasma potassium levels were observed in some units of irradiated packed red blood cells (range, 13.9 to 66.5 mEq/L; mean, 44.7 mEq/L) and could be one possible explanation for the high incidence of fetal arrhythmia associated with fetal intravascular transfusion. There are many factors operative in the preparation of irradiated packed red blood cells that may predispose to high potassium levels: the age of the red blood cells, the number of procedures used to concentrate the blood, the duration of time elapsed from concentration, the duration of time elapsed from irradiation, and the hematocrit. Use of fresh blood, avoidance of multiple packing procedures, limiting the hematocrit in the donor unit to less than or equal to 80%, and minimizing the time between concentration, irradiation and transfusion may minimize the potassium levels, and therefore making an additional washing procedure unnecessary.

  13. [Evaluation of non-compliance of transfusion requests of packed red blood cells].

    PubMed

    Ben Romdhane, Asma Rym; Ben Ayoub, Wided; Gouider, Emna

    2015-06-01

    Despite legislative acts develloped, many deficiencies were identified in blood requests at the National Blood TransfusionCenter impedding board and blood safety. to evaluate the conformity of the different topics of packed red blood cells requests to the legislation. Our study was prospective descriptive lasting six months (March-August 2011). It assessed all packed red blood cells requests which reached the national blood transfusion center. 16064 packed red blood cells requests from 21 public institutions and 28 private institutions were studied. There was different deficiencies in each item.The absence of birth date in 67.18% of request represented the largest non-compliance within administrative information. A predominance of shortcomings related to transfusion and obstetric history was recorded for clinical information with absence of date of the last transfusion in 91.72% cases, lack of accuracy of any previous transfusion reactions in 88.63% cases and absence of the number of previous pregnancies in 93.15% of transfusion requests prescribed to women. Non-conformities related to the prescribing physician concerned mainly the phone number which was absent in 55.82% of cases. This study revealed a significant lack of awareness of physicians in relation to the law governing transfusion. It is therefore essential to develop training for prescribers to improve transfusion safety.

  14. ["As white as snow, as red as blood..."].

    PubMed

    Petrilli, Alessandro

    2005-01-01

    The paper deals with the tale of Biancaneve and the seven dwarfs, by Grimm, used by the Author as a background to discuss the metaphorical function performed by blood images into the psychological relationship between parents and children. This allows a description of a feminine character which, already present in Greek mythology, at the origins of the Western civilization, has been apparently lost in the forthcoming Western cultural history, nonetheless strongly surviving in the construction of the consciousness and soul of women.

  15. Red blood cells and thrombin generation in sickle cell disease.

    PubMed

    Whelihan, Matthew F; Lim, Ming Y; Key, Nigel S

    2014-05-01

    The prothrombotic nature of sickle cell disease (SCD) is evidenced by the chronically elevated levels of almost all coagulation activation biomarkers, and an increased incidence of certain thrombotic events, including venous thromboembolism. Numerous studies have attempted to define the extent and elucidate the mechanism of the observed increase in thrombin generation in SCD patients in vivo. In general, these studies were performed using thrombin generation assays in platelet poor or platelet rich plasma and showed little difference in endogenous thrombin potential between the SCD cohort and healthy matched controls. In SCD, erythrocytes and monocytes have been demonstrated to exhibit procoagulant characteristics. Thus, the absence of these cellular components in standard thrombin generation assays may fail to reflect global hypercoagulability in the whole blood of patients with SCD. We were therefore surprised to see no difference in net thrombin generation in tissue factor-initiated initiated clotting of whole blood from patients with SCD. However, we are continuing to reconcile these seemingly disparate observations by slight modifications of the whole blood model that include alternative coagulation triggers and a re-examination of the net thrombin generation when the protein/protein S system is simultaneously interrogated.

  16. Interaction of fine particles and nanoparticles with red blood cells visualized with advanced microscopic techniques.

    PubMed

    Rothen-Rutishauser, Barbara M; Schürch, Samuel; Haenni, Beat; Kapp, Nadine; Gehr, Peter

    2006-07-15

    So far, little is known about the interaction of nanoparticles with lung cells, the entering of nanoparticles, and their transport through the blood stream to other organs. The entering and localization of different nanoparticles consisting of differing materials and of different charges were studied in human red blood cells. As these cells do not have any phagocytic receptors on their surface, and no actinmyosin system, we chose them as a model for nonphagocytic cells to study how nanoparticles penetrate cell membranes. We combined different microscopic techniques to visualize fine and nanoparticles in red blood cells: (I) fluorescent particles were analyzed by laser scanning microscopy combined with digital image restoration, (II) gold particles were analyzed by conventional transmission electron microscopy and energy filtering transmission electron microscopy, and (III) titanium dioxide particles were analyzed by energy filtering transmission electron microscopy. By using these differing microscopic techniques we were able to visualize and detect particles < or = 0.2 microm and nanoparticles in red blood cells. We found that the surface charge and the material of the particles did not influence their entering. These results suggest that particles may penetrate the red blood cell membrane by a still unknown mechanism different from phagocytosis and endocytosis.

  17. Effects of He-Ne laser irradiation on red blood cells in vitro

    NASA Astrophysics Data System (ADS)

    Ghadage, Vijay H.; Kulkarni, Gauri R.

    2011-03-01

    Laser radiation has many applications in biomedical field, such as wound healing, tissue repairing, heating and ablation processes. Intravenous low power laser radiation is used clinically for skin and vascular disorders. Laser radiation improves microcirculation and modulates the rheological properties of blood. FTIR (Fourier Transform Infra Red Spectra) is used to see the structural changes in erythrocyte membrane. In the present work He Ne laser (λ= 632nm, power=2mW) is used to irradiate human Red blood cells. Red blood cells are separated from human whole blood using centrifugation method (time=10 min., temperature=15°C and RPM=3000) and then exposed to HeNe laser radiation. Laser exposure time is varied from 10 min. to 40min for Red blood cells. Absorption spectrum, FTIR and fluorescence spectra of RBC are compared before and after HeNe laser irradiation. The absorption spectrum of RBC after exposure to HeNe laser shows a significant decrease in absorbance. The FTIR spectrum of non irradiated RBC clearly show the peaks due to O-H (free group), C=O (amide I group), N=O (nitro group), C-O (anhydride group) and C-H (aromatic group). Laser radiation changes in transmittance in FTIR spectra related to C=O group and percentage of transmittance increases for O-H, C=C, N=O, C-O and C-H group.

  18. Mapping viscoelastic properties of healthy and pathological red blood cells at the nanoscale level.

    PubMed

    Ciasca, G; Papi, M; Di Claudio, S; Chiarpotto, M; Palmieri, V; Maulucci, G; Nocca, G; Rossi, C; De Spirito, M

    2015-10-28

    In order to pass through the microcirculation, red blood cells (RBCs) need to undergo extensive deformations and to recover the original shape. This extreme deformability is altered by various pathological conditions. On the other hand, an altered RBC deformability can have major effects on blood flow and can lead to pathological implications. The study of the viscoelastic response of red blood cells to mechanical stimuli is crucial to fully understand deformability changes under pathological conditions. However, the typical erythrocyte biconcave shape hints to a complex and intrinsically heterogeneous mechanical response that must be investigated by using probes at the nanoscale level. In this work, the local viscoelastic behaviour of healthy and pathological red blood cells was probed by Atomic Force Microscopy (AFM). Our results clearly show that the RBC stiffness is not spatially homogeneous, suggesting a strong correlation with the erythrocyte biconcave shape. Moreover, our nanoscale mapping highlights the key role played by viscous forces, demonstrating that RBCs do not behave as pure elastic bodies. The fundamental role played by viscous forces is further strengthened by the comparison between healthy and pathological (diabetes mellitus) RBCs. It is well known that pathological RBCs are usually stiffer than the healthy ones. Our measures unveil a more complex scenario according to which the difference between normal and pathological red blood cells does not merely lie in their stiffness but also in a different dynamical response to external stimuli that is governed by viscous forces.

  19. Reflectance confocal microscopy of red blood cells: simulation and experiment (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Zeidan, Adel; Yeheskely-Hayon, Daniella; Minai, Limor; Yelin, Dvir

    2016-03-01

    The properties of red blood cells are a remarkable indicator of the body's physiological condition; their density could indicate anemia or polycythemia, their absorption spectrum correlates with blood oxygenation, and their morphology is highly sensitive to various pathologic states including iron deficiency, ovalocytosis, and sickle cell disease. Therefore, measuring the morphology of red blood cells is important for clinical diagnosis, providing valuable indications on a patient's health. In this work, we simulated the appearance of normal red blood cells under a reflectance confocal microscope and discovered unique relations between the cells' morphological parameters and the resulting characteristic interference patterns. The simulation results showed good agreement with in vitro reflectance confocal images of red blood cells, acquired using spectrally encoded flow cytometry (SEFC) that imaged the cells during linear flow and without artificial staining. By matching the simulated patterns to the SEFC images of the cells, the cells' three-dimensional shapes were evaluated and their volumes were calculated. Potential applications include measurement of the mean corpuscular volume, cell morphological abnormalities, cell stiffness under mechanical stimuli, and the detection of various hematological diseases.

  20. Nationwide outbreak of red eye syndrome associated with transfusion of leukocyte-reduced red blood cell units.

    PubMed

    Alonso-Echanove, Juan; Sippy, Brian D; Chin, Arthur E; Cairns, Lisa; Haley, Rebecca; Epstein, Jay S; Richards, Michael J; Edelhauser, Henry; Hedberg, Katrina; Kuehnert, Matthew J; Jarvis, William R; Pearson, Michele L

    2006-11-01

    To characterize red eye reactions occurring within 24 hours after receipt of units of leukocyte-reduced red blood cells, determine their etiology, and investigate their potential link to transfusion. We conducted a survey of transfusion facilities nationwide to determine the scope and magnitude of the reactions; performed case-control and cohort studies among transfused patients at the facility where most reactions occurred; and performed animal experiments, using cellulose acetate derivatives extracted from leukocyte-reduction filters and filter precursors, to reproduce reactions. From January 1, 1997, through January 15, 1998, we identified 159 reactions in 117 patients from 17 states. Reactions were characterized by conjunctival erythema or hemorrhage (in 100% of patients), eye pain (in 62%), photophobia (in 46%), and decreased visual acuity (in 32%). Symptom onset occurred 1-24 hours after initiation of transfusion and resolved within a median of 5 days. Reactions were associated with transfusion sessions that included units of red blood cells filtered with a specific brand of filter, the LeukoNet filter (HemaSure) (odds ratio, 100.4; P<.001). There was a dose-response relationship between the number of LeukoNet-filtered units transfused and the attack rate for reactions, ranging from 0.8% among sessions in which 1 unit was transfused to 27.3% among sessions in which 3 or more units were transfused (P<.001). A similar ocular syndrome was elicited in rabbits injected with cellulose acetate derivatives extracted from unused LeukoNet filters or filter precursors. No reactions were reported after LeukoNet filters were withdrawn from the market. This transfusion-associated red eye syndrome was linked to a specific brand of leukocyte-reduction filter and likely resulted from cellulose acetate derivatives leached from the filter membrane.

  1. Laser Doppler perfusion imaging of skin blood flow using red and near-infrared sources.

    PubMed

    Abbot, N C; Ferrell, W R; Lockhart, J C; Lowe, J G

    1996-12-01

    At present, scanning laser Doppler imaging uses a 633-nm helium-neon laser (RED) as the only light source, but this restricts its ability to measure blood flow (i) at darkly pigmented skin and (ii) from deeper or subdermal structures. Because near-infrared (NIR) light is known to penetrate deeper into tissue and to be less absorbed than RED, two imagers were adapted to include a NIR laser diode source (one of 830 nm for UK studies; one of 780 nm for leprosy field trials) in parallel with the existing RED source. In human hands representing a range of skin pigmentations, RED scans were unobtainable at the darkest areas of skin, but intact NIR scans could be collected in all cases. In experiments at the rat knee and the dorsal human hand, NIR and RED values were similar on normal skin. Over underlying vessels, however, NIR values greatly exceeded RED values, an effect abolished by occlusion. Similarly, in patients with leprosy and in healthy controls in Spain, fingerpulp NIR values exceeded RED values to the greatest degree when thermoregulatory flow was highest, i.e., when the deeper-lying arteriovenous anastomoses were open. Over areas of experimental inflammation, NIR gave higher values and also exhibited a greater degree of spatial heterogeneity than RED. We conclude that some current limitations of laser Doppler imaging technology can be overcome by the use of NIR laser diode sources.

  2. Screening for intermediate and severe forms of thalassaemia in discarded red blood cells: optimization and feasibility.

    PubMed

    George, Elizabeth; Lai, Mei I; Teh, Lai Kuan; Ramasamy, Rajesh; Goh, Ern Huei; Asokan, Kamalan; Tan, J A M A; Vasudevan, Maithili; Low, Sharon

    2011-12-01

    Detection and quantification of Hb subtypes of human blood is integral to presumptive identification of thalassaemias. It has been used in neonatal screening of thalassaemia and Hb variants. The use of discarded red blood cells following processing of the cord blood for stem cells provides readily available diagnostic material for thalassaemia screening. In this study, we determined the range of Hb subtypes in 195 consecutive cord blood samples collected for cord blood banking. The 'cord blood samples' analysed were those of the remaining red blood cells after the cord blood was processed for stem cell storage. Quantification of Hb subtypes by high performance liquid chromatography (HPLC) was done on BioRad Variant II Hb testing system. Only 73 (36.5%) of the samples could be analyzed neat without dilution. With a 1:300 dilution with wash solution the acceptable area as recommended by the manufacturer for reading of a C-gram within the 1 to 3 million ranges were achieved in all. Eighteen (9%) 12 showed classical Hb Barts (y4) prerun peaks were confirmed by Sebia Hydrasys automated Hb gel electrophoresis and quantified by Sebia Capillarys 2 capillary electrophoresis. Only 1 (0.5%) was presumptively identified with HbH disease. Due to the limited number of samples no beta-thalassaemia major, Hb E beta-thalassaemia and Hb Barts hydrops fetalis were found. The HPLC assay was possible at a cost US$ 5 per sample and a turnover time of 10 samples per hour without technical difficulties. This study reports an effective and valuable protocol for thalassaemia screening in red blood cells which would otherwise be discarded during cord blood processing. Cord blood with severe and intermediate forms of thalassaemia can be preselected and not stored.

  3. Canine Dal Blood Type: A Red Cell Antigen Lacking in Some Dalmatians

    PubMed Central

    Blais, Marie-Claude; Berman, Lisa; Oakley, Donna A.; Giger, Urs

    2011-01-01

    Background Based upon alloantibodies produced after sensitizing dogs with transfused blood, more than a dozen blood group systems have been recognized thus far, and some have been classified as dog erythrocyte antigens (DEA). Hypothesis A new canine red cell antigen was suspected, based on the development of specific alloantibodies in a Dalmatian previously sensitized by blood transfusions. Animals Twenty-six Dalmatians (including 1 Dalmatian in need of blood compatibility studies); 55 canine blood donors. Methods Serologic tests, including bloo