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Sample records for preventing red blood

  1. Characterization at the individual cell level and in whole blood samples of shear stress preventing red blood cells aggregation.

    PubMed

    Lee, K; Kinnunen, M; Danilina, A V; Ustinov, V D; Shin, S; Meglinski, I; Priezzhev, A V

    2016-05-01

    The aggregation of red blood cells (RBC) is an intrinsic feature of blood that has a strong impact on its microcirculation. For a number of years it has been attracting a great attention in basic research and clinical studies. Here, we study a relationship between the RBC aggregation parameters measured at the individual cell level and in a whole blood sample. The home made optical tweezers were used to measure the aggregating and disaggregating forces for a pair of interacting RBCs, at the individual cell level, in order to evaluate the corresponding shear stresses. The RheoScan aggregometer was used for the measurements of critical shear stress (CSS) in whole blood samples. The correlation between CSS and the shear stress required to stop an RBC pair from aggregating was found. The shear stress required to disaggregate a pair of RBCs using the double channel optical tweezers appeared to be about 10 times higher than CSS. The correlation between shear stresses required to prevent RBCs from aggregation at the individual cell level and in whole blood samples was estimated and assessed quantitatively. The experimental approach developed has a high potential for advancing hemorheological studies. PMID:26916508

  2. Red blood cell production

    MedlinePlus Videos and Cool Tools

    ... or another. Red blood cells are an important element of blood. Their job is to transport oxygen ... hemocytoblasts give rise to all of the formed elements in blood. If a hemocytoblast commits to becoming ...

  3. Red blood cell production

    MedlinePlus

    ... cells are an important element of blood. Their job is to transport oxygen to the body’s tissues in exchange for carbon dioxide, which is carried to and eliminated by the lungs. Red blood cells are formed in the red bone marrow of bones. Stem cells in the red bone marrow called hemocytoblasts ...

  4. Glutathione loading prevents free radical injury in red blood cells after storage.

    PubMed

    Dumaswala, U J; Wilson, M J; Wu, Y L; Wykle, J; Zhuo, L; Douglass, L M; Daleke, D L

    2000-11-01

    We have previously demonstrated that the loss of glutathione (GSH) and GSH-peroxidase (GSH-PX) in banked red blood cells (RBCs) is accompanied by oxidative modifications of lipids, proteins and loss of membrane integrity. The objective of this study was to determine whether artificial increases in antioxidant (GSH) or antioxidant enzyme (catalase) content could protect membrane damage in the banked RBCs following an oxidant challenge. RBCs stored at 1-6 degrees C for 0, 42 and 84 days in a conventional additive solution (Adsol) were subjected to oxidative stress using ferric/ascorbic acid (Fe/ASC) before and after enriching them with GSH or catalase using a hypotonic lysis-isoosmotic resealing procedure. This lysis-resealing procedure in the presence of GSH/catalase raised intracellular GSH and catalase concentrations 4-6 fold, yet produced only a small reduction in mean cell volume (MCV), mean cell hemoglobin (MCH) and mean cell hemoglobin concentrations (MCHC). Indicators of oxidative stress and membrane integrity were measured, including acetylcholinesterase (AChE) activity, GSH concentration, phosphatidylserine (PS) externalization (prothrombin-converting activity) and transmembrane lipid movements (14C-lyso phosphatidylcholine flip-flop and PS transport). GSH-enrichment protected AChE activity in fresh (0 day) and stored (42 and 84 days) RBCs from Fe/ASC oxidation by 10, 23 and 26%, respectively, compared with not-enriched controls. Following oxidative stress, the rate of transbilayer lipid flip-flop did not increase in fresh cells, but increased 9.3% in 42-day stored cells. Phosphatidylserine exposure, as measured by prothrombinase activity, increased 2.4-fold in fresh and 5.2-fold in 42-day stored cells exposed to Fe/ASC. Previous studies have shown that 42-day storage causes a moderate decrease in PS transport (approximately 50%), whereas transport rates declined by up to 75% in stored RBCs when challenged with Fe/ASC. GSH-enrichment prevented the increase

  5. Red blood cell transfusion to treat or prevent complications in sickle cell disease: an overview of Cochrane reviews

    PubMed Central

    Estcourt, Lise J; Fortin, Patricia M; Hopewell, Sally; Trivella, Marialena

    2016-01-01

    This is the protocol for a review and there is no abstract. The objectives are as follows: To summarize the evidence in Cochrane reviews of the effectiveness and safety of red cell transfusions versus no transfusion, or restrictive (to increase the total haemoglobin) versus liberal (to decrease the haemoglobin S level below a specified percentage) transfusion, for treatment or prevention of complications experienced by people with SCD. PMID:27069421

  6. Red Blood Cell Antibody Identification

    MedlinePlus

    ... be limited. Home Visit Global Sites Search Help? RBC Antibody Identification Share this page: Was this page helpful? Also known as: Alloantibody Identification; Antibody ID, RBC; RBC Ab ID Formal name: Red Blood Cell ...

  7. Prevention of High Blood Pressure

    MedlinePlus

    ... page from the NHLBI on Twitter. Prevention of High Blood Pressure Healthy lifestyle habits, proper use of medicines, and ... prevent high blood pressure or its complications. Preventing High Blood Pressure Onset Healthy lifestyle habits can help prevent high ...

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

    MedlinePlus

    ... 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.

  9. 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.

  10. Red blood cells, sickle cell (image)

    MedlinePlus

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

  11. Red blood cells, sickle cell (image)

    MedlinePlus

    Sickle cell anemia 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 this photomicrograph.

  12. Storing red blood cells with vitamin C and N-acetylcysteine prevents oxidative stress-related lesions: a metabolomics overview

    PubMed Central

    Pallotta, Valeria; Gevi, Federica; D’Alessandro, Angelo; Zolla, Lello

    2014-01-01

    Background Recent advances in red blood cell metabolomics have paved the way for further improvements of storage solutions. Materials and methods In the present study, we exploited a validated high performance liquid chromatography-mass spectrometry analytical workflow to determine the effects of vitamin C and N-acetylcysteine supplementation (anti-oxidants) on the metabolome of erythrocytes stored in citrate-phosphate-dextrose saline-adenine-glucose-mannitol medium under blood bank conditions. Results We observed decreased energy metabolism fluxes (glycolysis and pentose phosphate pathway). A tentative explanation of this phenomenon could be related to the observed depression of the uptake of glucose, since glucose and ascorbate are known to compete for the same transporter. Anti-oxidant supplementation was effective in modulating the redox poise, through the promotion of glutathione homeostasis, which resulted in decreased haemolysis and less accumulation of malondialdehyde and oxidation by-products (including oxidized glutathione and prostaglandins). Discussion Anti-oxidants improved storage quality by coping with oxidative stress at the expense of glycolytic metabolism, although reservoirs of high energy phosphate compounds were preserved by reduced cyclic AMP-mediated release of ATP. PMID:25074788

  13. Preventing and Treating Blood Clots

    MedlinePlus

    ... and Treating Blood Clots Request Permissions Download PDF Preventing and Treating Blood Clots January 20, 2015 To ... 2013, ASCO updated the clinical practice guideline about preventing and treating blood clots for people with cancer ...

  14. 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...

  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, 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...

  18. 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...

  19. Avoiding Anemia: Boost Your Red Blood Cells

    MedlinePlus

    ... link, please review our exit disclaimer . Subscribe Avoiding Anemia Boost Your Red Blood Cells If you’re ... and sluggish, you might have a condition called anemia. Anemia is a common blood disorder that many ...

  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. Preventing High Blood Pressure

    MedlinePlus

    ... this? Submit What's this? Submit Button Related CDC Web Sites Division for Heart Disease and Stroke Prevention ... this? Submit What's this? Submit Button Related CDC Web Sites Division for Heart Disease and Stroke Prevention ...

  2. High Blood Cholesterol Prevention

    MedlinePlus

    ... this? Submit What's this? Submit Button Related CDC Web Sites Division for Heart Disease and Stroke Prevention ... this? Submit What's this? Submit Button Related CDC Web Sites Division for Heart Disease and Stroke Prevention ...

  3. Red blood cells, sickle cells (image)

    MedlinePlus

    These crescent or sickle-shaped red blood cells (RBCs) are present with Sickle cell anemia, and stand out clearly against the normal round RBCs. These abnormally shaped cells may become entangled and ...

  4. Viscoelastic transient of confined red blood cells.

    PubMed

    Prado, Gaël; Farutin, Alexander; Misbah, Chaouqi; Bureau, Lionel

    2015-05-01

    The unique ability of a red blood cell to flow through extremely small microcapillaries depends on the viscoelastic properties of its membrane. Here, we study in vitro the response time upon flow startup exhibited by red blood cells confined into microchannels. We show that the characteristic transient time depends on the imposed flow strength, and that such a dependence gives access to both the effective viscosity and the elastic modulus controlling the temporal response of red cells. A simple theoretical analysis of our experimental data, validated by numerical simulations, further allows us to compute an estimate for the two-dimensional membrane viscosity of red blood cells, η(mem)(2D) ∼ 10(-7) N ⋅ s ⋅ m(-1). By comparing our results with those from previous studies, we discuss and clarify the origin of the discrepancies found in the literature regarding the determination of η(mem)(2D), and reconcile seemingly conflicting conclusions from previous works. PMID:25954871

  5. 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.

  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. Red blood cell membrane defects.

    PubMed

    Iolascon, Achille; Perrotta, Silverio; Stewart, Gordon W

    2003-03-01

    We present an overview of the currently known molecular basis of red cell membrane disorders. A detailed discussion of the structure of the red cell membrane and the pathophysiology and clinical aspects of its disorders is reported. Generally speaking, hereditary spherocytosis (HS) results from a loss of erythrocyte surface area. The mutations of most cases of HS are located in the following genes: ANK1, SPTB, SLC4A1, EPB42 and SPTA1, which encode for ankyrin, spectrin beta-chain, the anion exchanger 1 (band 3), protein 4.2 and spectrin alpha-chain, respectively. Hereditary elliptocytosis (HE) reflects a diminished elasticity of the skeleton. Its aggravated form, hereditary pyropoikilocytosis (HPP), implies that the skeleton undergoes further destabilization. The mutations responsible for HE and HPP, lie in the SPTA1 and SPTB gene, and in the EPB41 gene encoding protein 4.1. Allele alpha LELY is a common polymorphic allele, which plays the role of an aggravating factor when it occurs in trans of an elliptocytogenic allele of the SPTA1 gene. Southeast Asian ovalocytosis derives from a change in band 3. The genetic disorders of membrane permeability to monovalent cations required a positional cloning approach. In this respect, channelopathies represent a new frontier in the field. Dehydrated hereditary stomatocytosis (DHS) was shown to belong to a pleiotropic syndrome: DHS + fetal edema + pseudohyperkalemia, which maps 16q23-24. Splenectomy is strictly contraindicated in DHS and another disease of the same class, overhydrated hereditary stomatocytosis, because it increases the risk of thromboembolic accidents. PMID:14692233

  8. Red blood cell transfusion in newborn infants.

    PubMed

    Whyte, Robin K; Jefferies, Ann L

    2014-04-01

    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

  9. 21 CFR 660.30 - Reagent Red Blood Cells.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... identify human blood-group antibodies. (b) Source. Reagent Red Blood Cells shall be prepared from human... 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 §...

  10. Viscoelastic Transient of Confined Red Blood Cells

    PubMed Central

    Prado, Gaël; Farutin, Alexander; Misbah, Chaouqi; Bureau, Lionel

    2015-01-01

    The unique ability of a red blood cell to flow through extremely small microcapillaries depends on the viscoelastic properties of its membrane. Here, we study in vitro the response time upon flow startup exhibited by red blood cells confined into microchannels. We show that the characteristic transient time depends on the imposed flow strength, and that such a dependence gives access to both the effective viscosity and the elastic modulus controlling the temporal response of red cells. A simple theoretical analysis of our experimental data, validated by numerical simulations, further allows us to compute an estimate for the two-dimensional membrane viscosity of red blood cells, ηmem2D ∼ 10−7 N⋅s⋅m−1. By comparing our results with those from previous studies, we discuss and clarify the origin of the discrepancies found in the literature regarding the determination of ηmem2D, and reconcile seemingly conflicting conclusions from previous works. PMID:25954871

  11. Responder individuality in red blood cell alloimmunization.

    PubMed

    Körmöczi, Günther F; Mayr, Wolfgang R

    2014-11-01

    Many different factors influence the propensity of transfusion recipients and pregnant women to form red blood cell alloantibodies (RBCA). RBCA may cause hemolytic transfusion reactions, hemolytic disease of the fetus and newborn and may be a complication in transplantation medicine. Antigenic differences between responder and foreign erythrocytes may lead to such an immune answer, in part with suspected specific HLA class II associations. Biochemical and conformational characteristics of red blood cell (RBC) antigens, their dose (number of transfusions and pregnancies, absolute number of antigens per RBC) and the mode of exposure impact on RBCA rates. In addition, individual circumstances determine the risk to form RBCA. Responder individuality in terms of age, sex, severity of underlying disease, disease- or therapy-induced immunosuppression and inflammation are discussed with respect to influencing RBC alloimmunization. For particular high-risk patients, extended phenotype matching of transfusion and recipient efficiently decreases RBCA induction and associated clinical risks. PMID:25670932

  12. Alteration of red blood cell aggregation during blood storage

    NASA Astrophysics Data System (ADS)

    Lim, Hyun-Jung; Nam, Jeong-Hun; Lee, Byoung-Kwon; Suh, Jang-Soo; Shin, Sehyun

    2011-06-01

    Even though the trade-off between the benefits and risks of blood transfusion has been discussed for the last several decades, it requires further understanding of the rheological changes in stored blood that include the alteration of red blood cell (RBC) aggregation. The RBC aggregation of stored blood in its autologous plasma was monitored through the storage period (35 days). The critical shear stress, as a measure of RBC aggregation, was determined by using a microfluidic aggregometer. Blood was processed into a blood bag containing the anticoagulant CPDA1 and stored at 4°C. It was subjected to assays after zero, seven, 14, and 35 days. The critical shear stress for stored blood did not change up to 14 days of storage but exhibited a significant decrease after 35 days of storage. These results were identical to those of the conventional aggregation index (AI). Also, in the alteration of RBC aggregation for blood storage, the effect of the plasma factor was slightly stronger than that of the cellular factor. Through the present study, the critical shear stress as a new measure of RBC aggregation may help to monitor and control the quality of blood storage.

  13. 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... enzyme assay. (a) Identification. Red blood cell enzyme assay is a device used to measure the activity in... kinase or 2,3-diphosphoglycerate. A red blood cell enzyme assay is used to determine the enzyme...

  14. 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... enzyme assay. (a) Identification. Red blood cell enzyme assay is a device used to measure the activity in... kinase or 2,3-diphosphoglycerate. A red blood cell enzyme assay is used to determine the enzyme...

  15. 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... enzyme assay. (a) Identification. Red blood cell enzyme assay is a device used to measure the activity in... kinase or 2,3-diphosphoglycerate. A red blood cell enzyme assay is used to determine the enzyme...

  16. 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... enzyme assay. (a) Identification. Red blood cell enzyme assay is a device used to measure the activity in... kinase or 2,3-diphosphoglycerate. A red blood cell enzyme assay is used to determine the enzyme...

  17. 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... enzyme assay. (a) Identification. Red blood cell enzyme assay is a device used to measure the activity in... kinase or 2,3-diphosphoglycerate. A red blood cell enzyme assay is used to determine the enzyme...

  18. 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...

  19. 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...

  20. 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...

  1. 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...

  2. Blood Clots That Kill: Preventing DVT

    MedlinePlus

    ... on. Feature: Deep Vein Thrombosis Blood Clots That Kill: Preventing DVT Past Issues / Spring 2011 Table of ... More "Deep Vein Thrombosis" Articles Blood Clots That Kill: Preventing DVT / Skater Tara Lipinski Speaks Out About ...

  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. 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.

  5. Tissue engineering red blood cells: a therapeutic.

    PubMed

    van Veen, Theun; Hunt, John A

    2015-07-01

    The use of red blood cells (RBCs) in transfusion is widespread in modern medicine. Limitations in blood transfusion have made an urgent argument for the focus on alternatives, as particular medical treatments heavily rely on the supply of donated blood. Stem cells have been successfully used in vitro to produce RBCs and researchers are currently challenged with developing larger-scale culture methods to meet the requirements for clinically relevant cell numbers. The ultimate conditions that will be beneficial for this type of research are trivial. A successful human clinical trial has shown that tremendous progress has already been made in this field. Other alternatives are based on the oxygen carrier protein that RBCs contain, i.e. haemoglobin (Hb). Chemically defined molecules and crosslinked proteins, which are able to bind and transport oxygen, have been found to be functional in vivo. Major progress has been achieved, but developing highly suitable products for the transfusion market still remains an enormous challenge for these acellular blood substitutes. We provide a review about developing alternatives for blood transfusion, with the emphasis on tissue-engineering approaches. PMID:24753354

  6. 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.

  7. 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.

  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. Red and infrared light distribution in blood

    NASA Astrophysics Data System (ADS)

    de Magalhães, Ana Carolina; Yoshimura, Elisabeth M.

    2013-02-01

    Low level laser therapy (LLLT) is used in several applications, including the reduction of inflammatory processes. It might be used to prevent the systemic inflammatory response syndrome (SIRS), which some patients develop after cardiopulmonary bypass (CPB) surgery. The objectives of this study were to investigate light distribution inside blood, in order to implement the LLLT during CPB, and, through this study, to determine the best wavelength and the best way to perform the treatment. The blood, diluted to the same conditions of CPB procedure was contained inside a cuvette and an optical fiber was used to collect the scattered light. Two wavelengths were used: 632.8 nm and 820 nm. Light distribution in blood inside CPB tubes was also evaluated. Compared to the 820 nm light, the 632.8 nm light is scattered further away from the laser beam, turning it possible that a bigger volume of blood be treated. The blood should be illuminated through the smallest diameter CPB tube, using at least four distinct points around it, in only one cross section, because the blood is kept passing through the tube all the time and the whole volume will be illuminated.

  10. 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. PMID:26096663

  11. Red blood cell in simple shear flow

    NASA Astrophysics Data System (ADS)

    Chien, Wei; Hew, Yayu; Chen, Yeng-Long

    2013-03-01

    The dynamics of red blood cells (RBC) in blood flow is critical for oxygen transport, and it also influences inflammation (white blood cells), thrombosis (platelets), and circulatory tumor migration. The physical properties of a RBC can be captured by modeling RBC as lipid membrane linked to a cytoskeletal spectrin network that encapsulates cytoplasm rich in hemoglobin, with bi-concave equilibrium shape. Depending on the shear force, RBC elasticity, membrane viscosity, and cytoplasm viscosity, RBC can undergo tumbling, tank-treading, or oscillatory motion. We investigate the dynamic state diagram of RBC in shear and pressure-driven flow using a combined immersed boundary-lattice Boltzmann method with a multi-scale RBC model that accurately captures the experimentally established RBC force-deformation relation. It is found that the tumbling (TU) to tank-treading (TT) transition occurs as shear rate increases for cytoplasm/outer fluid viscosity ratio smaller than 0.67. The TU frequency is found to be half of the TT frequency, in agreement with experiment observations. Larger viscosity ratios lead to the disappearance of stable TT phase and unstable complex dynamics, including the oscillation of the symmetry axis of the bi-concave shape perpendicular to the flow direction. The dependence on RBC bending rigidity, shear modulus, the order of membrane spectrin network and fluid field in the unstable region will also be discussed.

  12. 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.”

  13. 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.

  14. 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.

  15. 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. PMID:26071649

  16. 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.

  17. 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. PMID:24273518

  18. 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

  19. Light scattering by aggregated red blood cells.

    PubMed

    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 < or = n < or = 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. PMID:11900021

  20. 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.

  1. Optimal serum and red blood cell folate concentrations in women of reproductive age for prevention of neural tube defects: World Health Organization guidelines.

    PubMed

    Cordero, Amy M; Crider, Krista S; Rogers, Lisa M; Cannon, Michael J; Berry, R J

    2015-04-24

    Neural tube defects (NTDs) such as spina bifida, anencephaly, and encephalocele are serious birth defects of the brain and spine that occur during the first month of pregnancy when the neural tube fails to close completely. Randomized controlled trials and observational studies have shown that adequate daily consumption of folic acid before and during early pregnancy considerably reduces the risk for NTDs. The U.S. Public Health Service recommends that women capable of becoming pregnant consume 400 µg of folic acid daily for NTD prevention. Furthermore, fortification of staple foods (e.g., wheat flour) with folic acid has decreased folate-sensitive NTD prevalence in multiple settings and is a highly cost-effective intervention. PMID:25905896

  2. Blood Disorders

    MedlinePlus

    ... and protein. Over half of your blood is plasma. The solid part of your blood contains red blood cells, white blood cells and platelets. Blood disorders affect one or more parts of the blood and prevent ...

  3. 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

  4. A single recombinant anti-RhD IgG prevents RhD immunization: association of RhD-positive red blood cell clearance rate with polymorphisms in the FcgammaRIIA and FcgammaIIIA genes.

    PubMed

    Miescher, Sylvia; Spycher, Martin O; Amstutz, Hanspeter; De Haas, Masja; Kleijer, Marion; Kalus, Ulrich J; Radtke, Hartmut; Hubsch, Alphonse; Andresen, Irmgard; Martin, Roland M; Bichler, Johann

    2004-06-01

    A single recombinant immunoglobulin G1 (IgG1) anti-RhD antibody (MonoRho) was compared with a currently used polyclonal anti-RhD product (Rhophylac) in a phase 1 study for safety, efficacy of Rhesus D (RhD)-positive red blood cell (RBC) clearance, and prevention of RhD immunization in RhD-negative men challenged with 15 mL RhD-positive RBCs. Both the polyclonal product and recombinant anti-RhD effectively cleared RhD-positive RBCs after intravenous and intramuscular injection. The recombinant anti-RhD demonstrated a slower clearance rate compared with the polyclonal anti-RhD. There was no dose response, and there was considerable variation among subjects who received the same dose of recombinant anti-RhD. Interestingly, RhD-positive RBC clearance rates were strongly associated with Fcgamma receptor IIA (FcgammaRIIA) and FcgammaIIIA but not with FcgammaIIIB polymorphisms. Subjects homozygous for FcgammaRIIA-131H or FcgammaRIIIA-158V allotypes showed a faster clearance rate compared with both the heterozygote and the corresponding alternative homozygote allotypes. A similar but less marked trend was seen for the polyclonal anti-RhD. Despite the variation in clearance rates there was no evidence of anti-RhD alloantibodies in any of the subjects at +6 months after the RBC challenge. PMID:14976055

  5. 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

  6. 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.

  7. 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

  8. Electrochemical Red Blood Cell Counting: One at a Time.

    PubMed

    Sepunaru, Lior; Sokolov, Stanislav V; Holter, Jennifer; Young, Neil P; Compton, Richard G

    2016-08-01

    We demonstrate that the concentration of a red blood cell solution under physiological conditions can be determined by electrochemical voltammetry. The magnitude of the oxygen reduction currents produced at an edge-plane pyrolytic graphite electrode was diagnosed analytically at concentrations suitable for a point-of-care test device. The currents could be further enhanced when the solution of red blood cells was exposed to hydrogen peroxide. We show that the enhanced signal can be used to detect red blood cells at a single entity level. The method presented relies on the catalytic activity of red blood cells towards hydrogen peroxide and on surface-induced haemolysis. Each single cell activity is expressed as current spikes decaying within a few seconds back to the background current. The frequency of such current spikes is proportional to the concentration of cells in solution. PMID:27355839

  9. 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. PMID:27039311

  10. Formation of dimethylthioarsenicals in red blood cells

    SciTech Connect

    Naranmandura, Hua; Suzuki, Kazuo T.

    2008-03-15

    The bladder and skin are the primary targets for arsenic-induced carcinogenicity in mammals. Thioarsenicals dimethylmonothioarsinic (DMMTA{sup V}) and dimethyldithioarsinic (DMDTA{sup V}) acids are common urinary metabolites, the former being much more toxic than non-thiolated dimethylarsinic acid (DMA{sup V}) and comparable to dimethylarsinous acid (DMA{sup III}) in epidermoid cells, suggesting that the metabolic production of thioarsenicals may be a risk factor for the development of cancer in these organs. To reveal their production sites (tissues/body fluids), we examined the uptake and transformation of the four dimethylated arsenicals by incubation with rat and human red blood cells (RBCs). Although DMA{sup V} and DMDTA{sup V} were not taken up by either type of RBCs, DMA{sup III} and DMMTA{sup V} were taken up by both (more efficiently by rat ones), though DMMTA{sup V} was taken up slowly, and then the arsenic transformed into DMDTA{sup V} was excreted from both types of animal RBCs. On the other hand, although DMA{sup III} taken up rapidly by rat RBCs was retained in the RBCs, that taken up by human RBCs was immediately transformed into DMMTA{sup V} and then excreted into the incubation medium without being retained in the RBCs. In a separate experiment, arsenic remaining in primary rat hepatocytes after incubation with 1.5 {mu}M DMA{sup III} was recovered from the incubation medium in the forms of DMA{sup V} and DMMTA{sup V} in the presence of human RBCs, but not in the presence of rat RBCs (in which the arsenic was bound to hemoglobin). Thus, DMMTA{sup V} was detected in the medium only in the presence of human RBCs and increased with incubation time. It was proposed that arsenic is excreted from hepatocytes into the bloodstream in the form of DMA{sup III} and then taken up by RBCs in humans, where it is transformed into DMMTA{sup V} and then excreted again into the bloodstream.

  11. 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.

  12. Acetylcholinesterase: an enzymatic marker of human red blood cell aging.

    PubMed

    Prall, Y G; Gambhir, K K; Ampy, F R

    1998-01-01

    The purpose of this investigation was to determine whether acetylcholinesterase (AChE) can be used as a marker of cell aging in human red blood cells (RBCs). This study used consented subjects; both males and females in an age range of 21-42 years. The blood samples (8-9 mL) were drawn in tubes containing sodium heparin or EDTA as anticoagulants. To avoid contamination with other cells, (lymphocytes, monocytes and reticulocytes), RBCs were purified (PRBC) by Hypaque-Ficoll gradient technique. The PRBCs were subfractionated into young (y) (1.08-1.09), mid (m) (1.09-1.11) and old (o) (1.11-1.12) percoll density (g/mL) fractions using a discontinuous percoll gradient. The mean +/- 1 SD AChE per gram hemoglobin (U/g Hgb) activities in whole blood (WB) purified human red blood cells (PRBCs), young human red blood cells (y-RBCs), mid age human red blood cells (m-RBCs) and old human red blood cells (o-RBCs) were 27.4 +/- 2.98, 26.0 +/- 2.33, 25.5 +/- 1.64, 20.3 +/- 3.84, 14.6 +/- 3.42 in males and 26.3 +/- 4.44, 24.8 /- 4.83, 26.4 +/- 4.59, 24.0 +/- 5.50 and 12.4 +/- 7.09 in females respectively. Although there was variation in the data, the results indicated that old human red blood cells showed significantly (p<.05) lower AChE activity compared to young human red blood cells of both sexes. These preliminary but novel observations suggest that AChE can be an excellent enzymatic marker for RBC aging in man. PMID:9698047

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

    PubMed

    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. PMID:23383842

  16. 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.

  17. 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

  18. Evaluation of the effectiveness of packed red blood cell irradiation by a linear accelerator

    PubMed Central

    Olivo, Ricardo Aparecido; da Silva, Marcus Vinícius; Garcia, Fernanda Bernadelli; Soares, Sheila; Rodrigues Junior, Virmondes; Moraes-Souza, Helio

    2015-01-01

    Irradiation of blood components with ionizing radiation generated by a specific device is recommended to prevent transfusion-associated graft-versus-host disease. However, a linear accelerator can also be used in the absence of such a device, which is the case of the blood bank facility studied herein. In order to evaluate the quality of the irradiated packed red blood cells, this study aimed to determine whether the procedure currently employed in the facility is effective in inhibiting the proliferation of T lymphocytes without damaging blood components. The proliferation of T lymphocytes, plasma potassium levels, and the degree of hemolysis were evaluated and compared to blood bags that received no irradiation. Packed red blood cell bags were irradiated at a dose of 25 Gy in a linear accelerator. For this purpose, a container was designed to hold the bags and to ensure even distribution of irradiation as evaluated by computed tomography and dose-volume histogram. Irradiation was observed to inhibit the proliferation of lymphocytes. The percentage of hemolysis in irradiated bags was slightly higher than in non-irradiated bags (p-value >0.05), but it was always less than 0.4% of the red cell mass. Although potassium increased in both groups, it was more pronounced in irradiated red blood cells, especially after seven days of storage, with a linear increase over storage time. The findings showed that, at an appropriate dosage and under validated conditions, the irradiation of packed red blood cells in a linear accelerator is effective, inhibiting lymphocyte proliferation but without compromising the viability of the red cells. PMID:26041416

  19. Impact of red blood cell transfusion on global and regional measures of oxygenation.

    PubMed

    Roberson, Russell S; Bennett-Guerrero, Elliott

    2012-01-01

    Anemia is common in critically ill patients. Although the goal of transfusion of red blood cells is to increase oxygen-carrying capacity, there are contradictory results about whether red blood cell transfusion to treat moderate anemia (e.g., hemoglobin 7-10 g/dL) improves tissue oxygenation or changes outcomes. Whereas increasing levels of anemia eventually lead to a level of critical oxygen delivery, increased cardiac output and oxygen extraction are homeostatic mechanisms the body uses to prevent a state of dysoxia in the setting of diminished oxygen delivery due to anemia. In order for cardiac output to increase in the face of anemia, normovolemia must be maintained. Transfusion of red blood cells increases blood viscosity, which may actually decrease cardiac output (barring a state of hypovolemia prior to transfusion). Studies have generally shown that transfusion of red blood cells fails to increase oxygen uptake unless oxygen uptake/oxygen delivery dependency exists (e.g., severe anemia or strenuous exercise). Recently, near-infrared spectroscopy, which approximates the hemoglobin saturation of venous blood, has been used to investigate whether transfusion of red blood cells increases tissue oxygenation in regional tissue beds (e.g., brain, peripheral skeletal muscle). These studies have generally shown increases in near-infrared spectroscopy derived measurements of tissue oxygenation following transfusion. Studies evaluating the effect of transfusion on the microcirculation have shown that transfusion increases the functional capillary density. This article will review fundamental aspects of oxygen delivery and extraction, and the effects of red blood cell transfusion on tissue oxygenation as well as the microcirculation. PMID:22238040

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

    PubMed Central

    Zeidan, Adel; Yelin, Dvir

    2015-01-01

    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. PMID:26600999

  1. "Keep the Beat": Healthy Blood Pressure Helps Prevent Heart Disease

    MedlinePlus

    ... Pressure "Keep the Beat": Healthy Blood Pressure Helps Prevent Heart Disease Past Issues / Winter 2010 Table of ... Articles "Keep the Beat": Healthy Blood Pressure Helps Prevent Heart Disease / Women and Heart Disease / Blood Pressure ...

  2. Contribution of the Retrovirus Epidemiology Donor Study (REDS) to research on blood transfusion safety in Brazil.

    PubMed

    Loureiro, Paula; de Almeida-Neto, Cesar; Proietti, Anna Bárbara Carneiro; Capuani, Ligia; Gonçalez, Thelma Terezinha; de Oliveira, Claudia Di Lorenzo; Leão, Silvana Carneiro; Lopes, Maria Inês; Sampaio, Divaldo; Patavino, Giuseppina Maria; Ferreira, João Eduardo; Blatyta, Paula Fraiman; Lopes, Maria Esther Duarte; Mendrone-Junior, Alfredo; Salles, Nanci Alves; King, Melissa; Murphy, Edward; Busch, Michael; Custer, Brian; Sabino, Ester Cerdeira

    2014-03-01

    The Retrovirus Epidemiology Donor Study (REDS) program was established in the United States in 1989 with the purpose of increasing blood transfusion safety in the context of the HIV/AIDS and human T-lymphotropic virus epidemics. REDS and its successor, REDS-II were at first conducted in the US, then expanded in 2006 to include international partnerships with Brazil and China. In 2011, a third wave of REDS renamed the Recipient Epidemiology and Donor Evaluation Study-III (REDS-III) was launched. This seven-year research program focuses on both blood banking and transfusion medicine research in the United States of America, Brazil, China, and South Africa. The main goal of the international programs is to reduce and prevent the transmission of HIV/AIDS and other known and emerging infectious agents through transfusion, and to address research questions aimed at understanding global issues related to the availability of safe blood. This article describes the contribution of REDS-II to transfusion safety in Brazil. Articles published from 2010 to 2013 are summarized, including database analyses to characterize blood donors, deferral rates, and prevalence, incidence and residual risk of the main blood-borne infections. Specific studies were developed to understand donor motivation, the impact of the deferral questions, risk factors and molecular surveillance among HIV-positive donors, and the natural history of Chagas disease. The purpose of this review is to disseminate the acquired knowledge and briefly summarize the findings of the REDS-II studies conducted in Brazil as well as to introduce the scope of the REDS-III program that is now in progress and will continue through 2018. PMID:24790542

  3. 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.

  4. Method for determining properties of red blood cells

    DOEpatents

    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.

  5. Dual network model for red blood cell membranes

    NASA Astrophysics Data System (ADS)

    Boal, David H.; Seifert, Udo; Zilker, Andreas

    1992-12-01

    A two-component network is studied by Monte Carlo simulation to model the lipid/spectrin membrane of red blood cells. The model predicts that the shear modulus decreases rapidly with the maximum length of the model spectrin and should be in the 10-7 J/m2 range for human red blood cells. A simplified model for the isolated spectrin network shows a negative Lamé coefficient λ. Transverse fluctuations of the dual membrane are found to be fluidlike over the range of wavelengths investigated.

  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. The Effect of Shape Memory on Red Blood Cell Motions

    NASA Astrophysics Data System (ADS)

    Niu, Xiting; Shi, Lingling; Pan, Tsorng-Whay; Glowinski, Roland

    2013-11-01

    An elastic spring model is applied to study the effect of the shape memory on the motion of red blood cell in flows. In shear flow, shape memory also plays an important role to obtain all three motions: tumbling, swinging, and tank-treading. In Poiseuille flow, cell has an equilibrium shape as a slipper or parachute depending on capillary number. To ensure the tank-treading motion while in slippery shape, a modified model is proposed by introducing a shape memory coefficient which describes the degree of shape memory in cells. The effect of the coefficient on the cell motion of red blood cell will be presented.

  8. Red blood cell and iron metabolism during space flight.

    PubMed

    Smith, Scott M

    2002-10-01

    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. PMID:12361780

  9. 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.

  10. Blood

    MedlinePlus

    ... solid part of your blood contains red blood cells, white blood cells, and platelets. Red blood cells (RBC) deliver oxygen from your lungs to your tissues and organs. White blood cells (WBC) fight infection and are part of your ...

  11. Red Blood Cell Spectrin Skeleton in the Spotlight.

    PubMed

    Braun-Breton, Catherine; Abkarian, Manouk

    2016-02-01

    Das et al. recently reported a role for the major merozoite surface protein MSP1 in malarial parasite egress from the red blood cell (RBC). On the basis of these new data and physical considerations, we propose an updated model for the main steps of this essential process for parasite proliferation. PMID:26652974

  12. Effects of Red Blood Cell Aggregation on the Apparent Viscosity of Blood Flow in Tubes.

    NASA Astrophysics Data System (ADS)

    Hitt, Darren L.; Lowe, Mary L.

    1996-11-01

    In arterioles and venules (20-200μ diameter), the low shear rates enable red blood cells to form aggregate structures of varying sizes and morphology. The size and distribution of the aggregates affect the flow impedance within a microvascular network; this effect may be characterized by an "apparent viscosity". In this study, we measure the apparent viscosity of blood flow in 50μ glass tubes as a function of shear rate and red blood cell volume fraction (hematocrit); for a fixed tube geometry and an imposed flow rate, the viscosity is determined by measuring the pressure drop across the tube. To correlate the apparent viscosity with the size and spatial distribution of the aggregates in the flow, video images of the flow are recorded and analyzed using power spectral techniques. Pig blood and sheep blood are used as the models for aggregating and non-aggregating blood, respectively. Supported by NSF PFF Award CTS-9253633

  13. Delayed cord clamping in red blood cell alloimmunization: safe, effective, and free?

    PubMed Central

    2016-01-01

    Hemolytic disease of the newborn (HDN), an alloimmune disorder due to maternal and fetal blood type incompatibility, is associated with fetal and neonatal complications related to red blood cell (RBC) hemolysis. After delivery, without placental clearance, neonatal hyperbilirubinemia may develop from ongoing maternal antibody-mediated RBC hemolysis. In cases refractory to intensive phototherapy treatment, exchange transfusions (ET) may be performed to prevent central nervous system damage by reducing circulating bilirubin levels and to replace antibody-coated red blood cells with antigen-negative RBCs. The risks and costs of treating HDN are significant, but appear to be decreased by delayed umbilical cord clamping at birth, a strategy that promotes placental transfusion to the newborn. Compared to immediate cord clamping (ICC), safe and beneficial short-term outcomes have been demonstrated in preterm and term neonates receiving delayed cord clamping (DCC), a practice that may potentially be effective in cases RBC alloimmunization. PMID:27186530

  14. Delayed cord clamping in red blood cell alloimmunization: safe, effective, and free?

    PubMed

    McAdams, Ryan M

    2016-04-01

    Hemolytic disease of the newborn (HDN), an alloimmune disorder due to maternal and fetal blood type incompatibility, is associated with fetal and neonatal complications related to red blood cell (RBC) hemolysis. After delivery, without placental clearance, neonatal hyperbilirubinemia may develop from ongoing maternal antibody-mediated RBC hemolysis. In cases refractory to intensive phototherapy treatment, exchange transfusions (ET) may be performed to prevent central nervous system damage by reducing circulating bilirubin levels and to replace antibody-coated red blood cells with antigen-negative RBCs. The risks and costs of treating HDN are significant, but appear to be decreased by delayed umbilical cord clamping at birth, a strategy that promotes placental transfusion to the newborn. Compared to immediate cord clamping (ICC), safe and beneficial short-term outcomes have been demonstrated in preterm and term neonates receiving delayed cord clamping (DCC), a practice that may potentially be effective in cases RBC alloimmunization. PMID:27186530

  15. 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

  16. 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). PMID:27282583

  17. A statistical model for red blood cell survival.

    PubMed

    Korell, Julia; Coulter, Carolyn V; Duffull, Stephen B

    2011-01-01

    A statistical model for the survival time of red blood cells (RBCs) with a continuous distribution of cell lifespans is presented. The underlying distribution of RBC lifespans is derived from a probability density function with a bathtub-shaped hazard curve, and accounts for death of RBCs due to senescence (age-dependent increasing hazard rate) and random destruction (constant hazard), as well as for death due to initial or delayed failures and neocytolysis (equivalent to early red cell mortality). The model yields survival times similar to those of previously published studies of RBC survival and is easily amenable to inclusion of drug effects and haemolytic disorders. PMID:20950630

  18. 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.

  19. 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. PMID:27114509

  20. 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.

  1. 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

  2. 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.

  3. TRANSFERRIN: VARIATIONS IN BLOOD SERUM OF RED HOWLER MONKEYS.

    PubMed

    SCHOEN, M A; ARENDS, T

    1964-11-01

    Blood serum samples from 33 red howler monkeys (Alouatta seniculus) were examined. Three different phenotypes were found and denominated A, B, and C. Four serums could not be classified because their transferrin apparently did not bind iron-59, possibly owing to saturation. A difference was observed in the electrophoretic migration and pattern of the transferrins in these monkeys compared with those of other primates. PMID:14197564

  4. Theory of the sphering of red blood cells.

    PubMed

    Fung, Y C; Tong, P

    1968-02-01

    A rigorous mathematical solution of the sphering of a red blood cell is obtained under the assumptions that the red cells is a fluid-filled shell and that it can swell into a perfect sphere in an appropriate hypotonic medium. The solution is valid for finite strain of the cell membrane provided that the membrane is isotropic, elastic and incompressible. The most general nonlinear elastic stress-strain law for the membrane in a state of generalized plane stress is used. A necessary condition for a red cell to be able to sphere is that its extensional stiffness follow a specific distribution over the membrane. This distribution is strongly influenced by the surface tension in the cell membrane. A unique relation exists between the extensional stiffness, pressure differential, surface tension, and the ratio of the radius of the sphere to that of the undeformed red cell. The functional dependence of this stiffness distribution on various physical parameters is presented. A critique of some current literature on red cell mechanics is presented. PMID:5639934

  5. 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

  6. 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. PMID:26163133

  7. 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. PMID:26921359

  8. Bacterial glycosidases for the production of universal red blood cells.

    PubMed

    Liu, Qiyong P; Sulzenbacher, Gerlind; Yuan, Huaiping; Bennett, Eric P; Pietz, Greg; Saunders, Kristen; Spence, Jean; Nudelman, Edward; Levery, Steven B; White, Thayer; Neveu, John M; Lane, William S; Bourne, Yves; Olsson, Martin L; Henrissat, Bernard; Clausen, Henrik

    2007-04-01

    Enzymatic removal of blood group ABO antigens to develop universal red blood cells (RBCs) was a pioneering vision originally proposed more than 25 years ago. Although the feasibility of this approach was demonstrated in clinical trials for group B RBCs, a major obstacle in translating this technology to clinical practice has been the lack of efficient glycosidase enzymes. Here we report two bacterial glycosidase gene families that provide enzymes capable of efficient removal of A and B antigens at neutral pH with low consumption of recombinant enzymes. The crystal structure of a member of the alpha-N-acetylgalactosaminidase family reveals an unusual catalytic mechanism involving NAD+. The enzymatic conversion processes we describe hold promise for achieving the goal of producing universal RBCs, which would improve the blood supply while enhancing the safety of clinical transfusions. PMID:17401360

  9. 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. PMID:21096766

  10. 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.

  11. 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

  12. 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.

  13. Oxidative inhibition of red blood cell ATPases by glyceraldehyde.

    PubMed

    Mira, M L; Martinho, F; Azevedo, M S; Manso, C F

    1991-11-01

    Glyceraldehyde and other simple monosaccharides autoxidize under physiological conditions, forming dicarbonyl compounds and hydrogen peroxide via intermediate free radicals. These products may have deleterious effects on cell components. In this paper we study the effect of glyceraldehyde autoxidation on red-cell ATPase activities. The autoxidation of glyceraldehyde in imidazole-glycylglycine buffer, measured by oxygen consumption, depends on the buffer concentration and decreases in the presence of superoxide dismutase and catalase. The addition of DETAPAC inhibits the autoxidation almost completely. When human red-blood-cell membranes are incubated with glyceraldehyde, the red-blood-cell ATPase activities decrease significantly. The addition of DETAPAC, GSH and DTE (dithioerythritol) protects the enzyme from inactivation, but superoxide dismutase and catalase have no effect. Methylglyoxal (a dicarbonyl which is analogous to hydroxypyruvaldehyde derived from glyceraldehyde autoxidation) proved to have a powerful inhibitory action on ATPase activities. The addition of DTE completely protects the enzyme from inactivation, suggesting that the sulphydryl groups of the active site of the enzyme are the critical targets for dicarbonyl compounds. PMID:1836354

  14. Changes in En(a-) human red blood cell membranes during in vivo ageing.

    PubMed

    Shinozuka, T; Miyata, Y; Takei, S; Yoshida, R; Ogamo, A; Nakagawa, Y; Kuroda, N; Yanagida, J

    1996-01-01

    The human red blood cells with phenotype En(a-) were characterized by the lack of MN antigens. The red blood cells with phenotype En(a-) which were found in a Japanese family were tested to clarify the changes in membrane surfaces of the red blood cells during in vivo ageing. The contents of sialic acid, glucose, mannose, galactose, fucose, N-acetylglucosamine and N-acetylgalactosamine of the red blood cell membranes obtained from the old red blood cells with phenotype En(a-) were significantly lower than those of the young red blood cell membranes. Neither the young nor the old red blood cells with phenotype En(a-) showed the agglutination with Arachis hypogaea (PNA) which was capable of binding to T agglutinogen. It is presumed that En(a-) red blood cells are not exposed to sialidase in vivo. In comparison with the young En(a-) red blood cell membranes, the number and the distribution density of lectin receptor sites on the old ones for Limulus polyphemus (LPA), Canavalia ensiformis (Con A), Triticum vulgaris (WGA) and Bauhinia purpurea (BPA) were significantly lower. It is thought that En(a-) red blood cell ageing is accompanied by elimination of some sialoglycoconjugates which have affinity for LPA, Con A, WGA and BPA, whereas En(a-) red blood cells lack glycophorin A. PMID:8866734

  15. 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

  16. 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.

  17. Flow of Red Blood Cells in Stenosed Microvessels.

    PubMed

    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

    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

  19. 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.

  20. 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.

  1. 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. PMID:15275396

  2. Cytoskeleton confinement of red blood cell membrane fluctuations

    NASA Astrophysics Data System (ADS)

    Gov, Nir; Zilman, Anton; Safran, Samuel

    2003-03-01

    We analyze theoretically both the static and dynamic fluctuation spectrum 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 predictions of the model account for the wavevector and frequency dependence of the experimental data.

  3. Cytoskeleton Confinement and Tension of Red Blood Cell Membranes

    NASA Astrophysics Data System (ADS)

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

    2003-06-01

    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.

  4. 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)

  5. 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

  6. Red Cell Properties after Different Modes of Blood Transportation.

    PubMed

    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), Ca(2+) 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(+), Ca(2+)) handling and, possibly, reticulocytes counts, tend to favor transportation at 4°C. Whereas plasma and intraerythrocytic Ca(2+) cannot be accurately measured in the presence of chelators such as citrate and EDTA, the majority of Ca(2+)-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

  7. 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.

  8. 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.

  9. 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).

  10. 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. PMID:1398371

  11. Red Blood Cells Motion in a Glass Microchannel

    NASA Astrophysics Data System (ADS)

    Pinho, Diana; Pereira, Ana I.; Lima, Rui

    2010-09-01

    The motion of the red blood cells (RBCs) flowing in microvessels and microchannels depend on several effects, such as hematocrit (Hct), geometry, and temperature. According to our knowledge, the effect of the temperature on RBC motion was never investigated at a microscale level. Hence, the aim of the present work is to determine the effect of the temperature on the RBC's trajectories and to investigate the best approximation of the trajectories through a nonlinear optimization. In vitro human blood was pumped through a 100 μm circular microchannel and by using a confocal micro-PTV system the RBC's trajectories were measured at different temperatures, i.e., 25° C and 37° C. In this study we measured the motion of forty cells flowing in the middle of the microchannel and applied different functions to approximate its behavior.

  12. Prevent Diabetes Problems: Keep Your Heart and Blood Vessels Healthy

    MedlinePlus

    ... Lung and Blood Institute American Diabetes Association JDRF Diabetes Disease Organizations Many organizations provide support to patients ... PDF, 293 KB). Alternate Language URL Español Prevent diabetes problems: Keep your heart and blood vessels healthy ...

  13. 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

  14. 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.

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

    PubMed Central

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

    2016-01-01

    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. PMID:27437432

  16. Enhancement of red blood cell aggregation by plasma triglycerides.

    PubMed

    Cicha, I; Suzuki, Y; Tateishi, N; Maeda, N

    2001-01-01

    The effects of plasma triglycerides level on human red blood cells (RBCs) indices, hematological parameters, RBCs aggregation velocity and whole blood viscosity were studied at 2 hours after high-fat or low-fat meal. Proteins, triglycerides and cholesterol levels of plasma were analysed. The RBCs rouleaux formation rate was measured in 70% autologous plasma (with 30% phosphate-buffered saline, PBS) or 1 g/dl dextran T70 solution (with 4 g/dl bovine serum albumin) in PBS, using a low-shear rheoscope. The results were grouped according to triglycerides content in plasma. No significant difference in whole blood viscosity, hematological parameters, RBC indices, protein and cholesterol content was observed between high-fat and low-fat blood samples. There was a significant increase in rouleaux formation rate of samples with high triglyceride levels, when measured in 70% autologous plasma, but it was not significant in dextran T70 containing medium. In conclusion, the results obtained suggest that alteration of plasma lipid levels as well as possible changes in the cell membrane lipid composition lead to enhanced RBC aggregation. PMID:11564913

  17. Hypochromicity in red blood cells: an experimental and theoretical investigation

    PubMed Central

    Nonoyama, Akihisa; Garcia-Lopez, Alicia; Garcia-Rubio, Luis H.; Leparc, German F.; Potter, Robert L.

    2011-01-01

    Multiwavelength UV-visible transmission spectrophotometry is a useful tool for the examination of micron-size particle suspensions in the context of particle size and chemical composition. This paper reports the reliability of this method to characterize the spectra of purified red blood cells both in their physiological state and with modified hemoglobin content. Previous studies have suggested the contribution of hypochromism on the particle spectra caused by the close electronic interaction of the encapsulated chromophores. Our research shows, however, that this perceived hypochromism can be accounted for by considering two important issues: the acceptance angle of the instrument and the combined scattering and absorption effect of light on the particles. In order to establish these ideas, spectral analysis was performed on purified and modified red cells where the latter was accomplished with a modified hypotonic shock protocol that altered the hemoglobin concentration within the cells. Moreover, the Mie theory was used to successfully simulate the spectral features and trends of the red cells. With this combination of experimental and theoretical exploration, definition of hypochromism has been extended to two subcategories. PMID:21833353

  18. Red blood cell distribution width and cardiovascular diseases

    PubMed Central

    Danese, Elisa; Lippi, Giuseppe

    2015-01-01

    Background The red blood cell distribution width (RDW) is a rather simple measure of red blood cell (RBC) size heterogeneity (i.e., anisocytosis), which is easily calculated by dividing the standard deviation (SD) of erythrocyte volumes for the mean corpuscular volume (MCV). Emerging evidence suggests that, besides RBC abnormalities, many human disorders may be frequently associated with a high degree of anisocytosis. Methods In this narrative review, we analyzed the current scientific literature about the putative role and the potential epidemiologic association between RDW and cardiovascular diseases. The findings of the most representative epidemiological studies were summarized and discussed. Results Overall, considerable and convincing evidence has been brought that an increased RDW value is associated with acute coronary syndrome (ACS) [including acute myocardial infarction (AMI)], ischemic cerebrovascular disease (including stroke), peripheral artery disease (PAD), as well as with atrial fibrillation (AF), heart failure (HF) and hypertension. Higher anisocytosis also significantly and independently predicts adverse outcomes in patients with these conditions. Conclusions Although the role of anisocytosis in the pathogenesis of cardiovascular diseases remains uncertain, the considerable evidence available so far suggests that the clinical use of RDW may be broadened beyond the conventional boundaries of erythrocyte disorders, in particular for assisting the diagnosis and prognostication of patients with ACS, ischemic cerebrovascular disease, PAD, HF and AF. PMID:26623117

  19. 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).

  20. Effects of ethanol on red blood cell rheological behavior

    PubMed Central

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

    2016-01-01

    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. PMID:23089886

  1. 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

  2. Red blood cell homeostasis: recognition of distinct types of damaged homologous red blood cells by a mouse macrophage cell line.

    PubMed

    Singer, J A; Morrison, M; Walker, W S

    1987-06-01

    The mouse macrophage (M phi) cell line IC-21 preferentially ingests a subpopulation of homologous red blood cells (MRBC) from normal mice. This subpopulation presumably bears the so-called transfusion lesion, a consequence of damage acquired during the drawing and processing of blood. To determine if all damaged MRBC were recognized by a common receptor site on IC-21 M phi, we prepared suspensions of MRBC damaged in vitro by treatment with tannic acid and compared the phagocytic uptake of these cells with those bearing the transfusion lesion. Trypsin treatment of IC-21 M phi rendered them unable to recognize MRBC bearing the transfusion lesion; but it had no effect on the uptake of tannic acid-damaged MRBC, showing that IC-21 M phi have separate recognition sites for these two populations of damaged MRBC. PMID:3474332

  3. Antibody-mediated red blood cell agglutination resulting in spontaneous echocardiographic contrast.

    PubMed

    Miller, M R; Thompson, W R; Casella, J F; Spevak, P J

    1999-01-01

    Spontaneous echocardiographic contrast is well reported in states of low flow and low shear stress, and the primary blood component involved has been reported as red blood cells via rouleaux formation. This report describes the occurrence of spontaneous echocardiographic contrast from a unique mechanism of IgM-mediated red blood cell agglutination and describes the clinical sequelae. PMID:10368455

  4. [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. PMID:26904817

  5. 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

  6. Paramagnetic Gd(3+) labeled red blood cells for magnetic resonance angiography.

    PubMed

    Aryal, Santosh; Stigliano, Cinzia; Key, Jaehong; Ramirez, Maricela; Anderson, Jeff; Karmonik, Christof; Fung, Steve; Decuzzi, Paolo

    2016-08-01

    Despite significant advances in contrast enhanced-magnetic resonance angiography, the lack of truly blood-pool agents with long circulating property is limiting the clinical impact of this imaging technique. The terminal half-life for blood elimination of most small molecular weight gadolinium (Gd) based extracellular fluid agents is about 1.5 h when administered intravenously to subjects with normal renal function. The small size of these extracellular fluid agents does not prevent them from extravasating, especially from damaged vessels which are generally hyperpermeable. Therefore, the development of novel, clinically relevant blood pool contrast agents is critically needed to improve outcomes in the prevention, detection, and treatment of vascular diseases. We have demonstrated the fusion strategies in which the Gd-liposome without any stealth property radically fuses with red blood cells (RBCs) forming MR glowing Gd-RBC with the order of magnitude enhancements in circulation half-life (t1/2 = 50 h) and r1 relaxivity (r1 = 19.0 mM(-1) s(-1)) of Gd. The in vivo contrast enhancement of Gd-RBC was studied by using 3T clinical MR scanner for extended period of time, which clearly visualized the abdominal aorta. In summary, the vascular delivery of blood pool agents may benefit from carriage by RBCs because it naturally stays within the vascular lumen. PMID:27192419

  7. 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. PMID:18649167

  8. Single-cell measurement of red blood cell oxygen affinity

    PubMed Central

    Di Caprio, Giuseppe; Stokes, Chris; Higgins, John M.; Schonbrun, Ethan

    2015-01-01

    Oxygen is transported throughout the body by hemoglobin (Hb) in red blood cells (RBCs). Although the oxygen affinity of blood is well-understood and routinely assessed in patients by pulse oximetry, variability at the single-cell level has not been previously measured. In contrast, single-cell measurements of RBC volume and Hb concentration are taken millions of times per day by clinical hematology analyzers, and they are important factors in determining the health of the hematologic system. To better understand the variability and determinants of oxygen affinity on a cellular level, we have developed a system that quantifies the oxygen saturation, cell volume, and Hb concentration for individual RBCs in high throughput. We find that the variability in single-cell saturation peaks at an oxygen partial pressure of 2.9%, which corresponds to the maximum slope of the oxygen–Hb dissociation curve. In addition, single-cell oxygen affinity is positively correlated with Hb concentration but independent of osmolarity, which suggests variation in the Hb to 2,3-diphosphoglycerate (2–3 DPG) ratio on a cellular level. By quantifying the functional behavior of a cellular population, our system adds a dimension to blood cell analysis and other measurements of single-cell variability. PMID:26216973

  9. Fibrinogen and red blood cells in venous thrombosis

    PubMed Central

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

    2014-01-01

    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. PMID:24759140

  10. 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

  11. 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.

  12. Blood flow structure related to red cell flow: determinant of blood fluidity in narrow microvessels.

    PubMed

    McHedlishvili, G; Maeda, N

    2001-02-01

    The review article deals with phenomena of the blood flow structure (structuring) in narrow microvessels-capillaries and the adjacent arterioles and venules. It is particularly focused on the flow behavior of red blood cells (RBCs), namely, on their specific arrangements of mutual interaction while forming definite patterns of self-organized microvascular flow. The principal features of the blood flow structure in microvessels, including capillaries, include axial RBC flow and parietal plasma layer, velocity profile in larger microvessels, plug (or bolus) flow in narrow capillaries, and deformation and specific behavior of the RBCs in the flow. The actual blood flow structuring in microvessels seems to be a most significant factor in the development of pathological conditions, including arterial hypertension, brain and cardiac infarctions, inflammation, and many others. The blood flow structuring might become a basic concept in determining the blood rheological properties and disorders in the narrow microvessels. No solid theoretical (biorheological) basis of the blood flow structuring in microvessel has been found, but in the future it might become a foundation for a better understanding of the mechanisms of these properties under normal and pathological conditions in the narrowest microvessels 5 to 25 microm large. It is also a topic for further biorheological research directed to find the background of actual physiopathological phenomena in the microcirculation. PMID:11281993

  13. 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.

  14. 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.

  15. Iron-Deficiency Anemia Enhances Red Blood Cell Oxidative Stress

    PubMed Central

    Nagababu, Enika; Gulyani, Seema; Earley, Christopher J.; Cutler, Roy G.; Mattson, Mark P.; Rifkind, Joseph M.

    2009-01-01

    Oxidative stress associated with iron deficiency anemia in a murine model was studied feeding an iron deficient diet. Anemia was monitored by a decrease in hematocrit and hemoglobin. For the 9 week study an increase in total iron binding capacity was also demonstrated. Anemia resulted in an increase in red blood cells (RBC) oxidative stress as indicated by increased levels of fluorescent heme degradation products (1.24 fold after 5 weeks; 2.1 fold after 9 weeks). The increase in oxidative stress was further confirmed by elevated levels of methemoglobin for mice fed an iron deficient diet. Increased hemoglobin autoxidation and subsequent generation of ROS can account for the shorter RBC lifespan and other pathological changes associated with iron deficiency anemia. PMID:19051108

  16. Measurement of the nonlinear elasticity of red blood cell membranes

    NASA Astrophysics Data System (ADS)

    Park, Yongkeun; Best, Catherine A.; Kuriabova, Tatiana; Henle, Mark L.; Feld, Michael S.; Levine, Alex J.; Popescu, Gabriel

    2011-05-01

    The membranes of human red blood cells (RBCs) are a composite of a fluid lipid bilayer and a triangular network of semiflexible filaments (spectrin). We perform cellular microrheology using the dynamic membrane fluctuations of the RBCs to extract the elastic moduli of this composite membrane. By applying known osmotic stresses, we measure the changes in the elastic constants under imposed strain and thereby determine the nonlinear elastic properties of the membrane. We find that the elastic nonlinearities of the shear modulus in tensed RBC membranes can be well understood in terms of a simple wormlike chain model. Our results show that the elasticity of the spectrin network can mostly account for the area compression modulus at physiological osmolality, suggesting that the lipid bilayer has significant excess area. As the cell swells, the elastic contribution from the now tensed lipid membrane becomes dominant.

  17. Dynamics of flat membranes and flickering in red blood cells

    NASA Astrophysics Data System (ADS)

    Frey, Erwin; Nelson, David R.

    1991-12-01

    A theory of the dynamics of polymerized membranes in the flat phase is presented. The dynamics of dilute membrane solutions is strongly influenced by long-ranged hydrodynamic interactions among the monomers, mediated by the intervening solvent. We discuss the renormalization of the kinetic coefficients for the undulation and phonon modes due to hydrodynamic “backflow” (Zimm behavior). The dynamics is also studied for free draining membranes (Rouse dynamics) corresponding to the Brownian dynamics method used in Monte Carlo simulations. The long time behavior of the dynamic structure factor is given by stretched exponentials with stretching exponents determined by the exponents of the elastic coefficients and the wave vector dependence of the Oseen tensor. We also study the dynamics of the thickness fluctuations in red blood cells (flicker phenomenon) taking into account the underlying polymerized spectrin skeleton. Qualitatively different dynamical behavior is predicted for spectrin skeletons isolated from heir natural lipid environment.

  18. Measurement of red blood cell mechanics during morphological changes

    NASA Astrophysics Data System (ADS)

    Popescu, Gabriel; Park, Yongkeun; Best, Catherine; Dasari, Ramachandra; Feld, Michael; Kuriabova, Tatiana; Henle, Mark; Levine, Alex

    2010-03-01

    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 and bending moduli. This mechanical transition can alter cell circulation and impede oxygen delivery.

  19. 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.

  20. 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. PMID:27150627

  1. 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

  2. Fetal anaemia from red blood cell membrane defect and co-inherited haemoglobin Constant Spring.

    PubMed

    Srisupundit, Kasemsri; Charoenkwan, Pimlak; Traisrisilp, Kuntharee; Tongsong, Theera

    2015-01-01

    The case presented here is an example of hereditary red blood cell membrane defect with a co-inherited haemoglobin Constant Spring. This case is of an anaemic fetus that presented with isolated ascites at 18 weeks of gestation. Fetal blood analysis revealed abnormal shaped red blood cells. The same pattern of red blood cell morphology was also seen on paternal peripheral blood smear. Intrauterine blood transfusions were given twice to correct fetal anaemia. The fetus showed a good response to the transfusions and was delivered at term with mild anaemia and did not need blood transfusion after birth. This report describes a natural course of red blood cell membrane defect with co-inherited haemoglobin Constant Spring, indicating that the course of disease was more severe during fetal life. Intrauterine transfusion supported the transition of the fetus through the critical period in utero to a healthier life after birth. PMID:26216922

  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. Red Blood Cell Antibodies in Hematology/Oncology Patients: Interpretation of Immunohematologic Tests and Clinical Significance of Detected Antibodies.

    PubMed

    Hendrickson, Jeanne E; Tormey, Christopher A

    2016-06-01

    Red blood cell (RBC) transfusion is a cornerstone of the management of patients with hematology/oncology disorders. However, a potentially deleterious consequence of transfusion is the development of alloantibodies against blood group antigens present on RBCs. Such alloantibodies can be an obstacle in providing compatible units for transfusion. Providers in this arena must fully understand the testing performed by blood banks, as well as the consequences of detected antibodies. This article reviews immunohematologic tests, describes how autoimmune hemolytic anemia is classified by autoantibodies; outlines RBC alloimmunization rates, and presents strategies to prevent/mitigate the impact of RBC alloimmunization. PMID:27113001

  5. Mach-Zehnder interferometer for separation of platelets from red blood cells using dielectrophoretics

    NASA Astrophysics Data System (ADS)

    Shwetha, M.; Narayan, K.

    2016-03-01

    In this work, separation of platelets from red blood cells using Mach-Zehnder interferometer is shown using Dielectrophoretics (DEP). The proposed model demonstrates continuous separation of platelets from red blood cells. Mach-Zehnder Interferometer (MZI) has two arms, in which sensing arm will sense according to the applied voltage and separate the platelets from mixed blood cells. The platelets and the red blood cells will flow in two outlets of MZI. Microfluidic device is used to separate the RBC's and the platelets from the mixed blood cells.

  6. 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.

  7. 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. PMID:12012283

  8. The aging of the red blood cell. A multifactor process.

    PubMed

    Danon, D; Marikovsky, Y

    1988-01-01

    Red blood cell (rbc) senescence is associated with loss of surface sialic acid, which is the principal carrier of surface negative charge and determines the electrokinetic behavior of old rbcs. Loss of sialic acid in an old rbc is demonstrated in its decreased electric mobility and lower negative charge density, determined topographically with cationic particle labeling. Surface sialic acid determines also the mutual attraction--repulsion forces, as demonstrated in enhanced aggluinability with cationic molecules, lectins, and blood group antibodies. Loss of sialic acid accompanies ATP-depletion in vitro; thus, a T-antigen site is unmasked. Macrophages have specific receptors to the site as to newly exposed galactose and N-acetyl galactosamine sugars. Furthermore, the involvement of complement molecules in the recognition of old RBCs by macrophages has been shown. This is possibly due to loss of sialic acid or at least a regrouping--relocation of surface anionic sites due to cell shape changes from discocytes to crenated forms, which accompany both in vivo and in vitro rbc aging. In turn, shape changes are apparently controlled by the cytoskeletal network underlying the rbc membrane, which undergoes structural alteration with physiologic aging in changing the dimensions of oligomeric spectrin and the thickness of the spectrin-actin cytoskeletal assembly. PMID:3052636

  9. 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.

  10. Immunoregulatory function of neonatal nucleated red blood cells in humans.

    PubMed

    Cui, Lili; Takada, Hidetoshi; Takimoto, Tomohito; Fujiyoshi, Junko; Ishimura, Masataka; Hara, Toshiro

    2016-08-01

    We found that human cord blood nucleated red blood cells (NRBCs) have a regulatory function in the innate immune reaction. These cells suppressed the production of inflammatory cytokines including TNF-α and IL-1β from monocytes in response to lipopolysaccharide (LPS). The NRBCs exerted their regulatory function even without cell-to-cell contact with the monocytes. However, IL-10 production from the monocytes by LPS stimulation in the presence of NRBCs was higher than that from LPS-stimulated monocytes cultured in the absence of NRBCs. Addition of an anti-IL-10 receptor blocking antibody restored the inflammatory cytokine production from the monocytes, suggesting that the functional change of the monocytes caused by the interaction with NRBCs was mediated by the increased IL-10 production. A whole-genome microarray analysis revealed that the monocytes expressed increased amounts of IL-10 superfamily genes after interacting with NRBCs. IL-19, which is a member of the IL-10 superfamily, enhanced IL-10 production from the monocytes, which suggested a cooperative role of the IL-10 superfamily in the suppression of inflammatory cytokine production from monocytes. Arginase, which was reported to play an important role in the suppressive function of NRBCs in mice monocytes, was found to have no significant role in human monocytes. The NRBCs seem to have a regulatory role through the induction of IL-10/IL-19 production by monocytes to suppress a vigorous innate immune reaction, which can be harmful to fetuses. PMID:27117669

  11. 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.

  12. 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. PMID:24879644

  13. Red blood cell deformability in diabetes mellitus: effect of phytomenadione.

    PubMed

    Sabo, A; Jakovljević, V; Stanulović, M; Lepsanović, L; Pejin, D

    1993-01-01

    Decreased deformability of red blood cells (RBC) in diabetes mellitus (DM) is considered to be linked to microcirculatory complications in this condition. As we found that phytomenadione increased RBC deformability in experimental animals, the question was raised, whether phytomenadione had the same effect on the RBC of diabetic patients. The study was performed in 10 patients with insulin-dependent diabetes mellitus, where the erythrocyte deformability was impaired. Patients received 10 mg/day phytomenadione i.m. for five days. Deformability was measured with policarbonate membranes (Nucleopore) with pore diameter 5 microns, under gravity. The results were expressed as the ratio (r) between the flow of 1.5 ml (r1) and 2 ml (r2) of RBC suspension and 1.5 ml of buffer. Phytomenadione increased the erythrocyte deformability in patients with diabetes mellitus, lowering the value r1 from 3.54 +/- 0.84 to 2.32 +/- 0.61 (p 0.02) and r2 from 7.80 +/- 2.41 to 4.65 +/- 1.07 (p 0.01). The values after treatment reached the range of healthy controls (r1 3.11 +/- 0.98, r2 6.52 +/- 3.04). The whole blood viscosity was significantly lowered after phytomenadione (5.28 +/- 0.58 mPas before, 4.64 +/- 0.74 mPas after, p < 0.02) with unchanged plasma viscosity, but significantly lowered internal viscosity of erythrocytes. PMID:8444511

  14. Effect of Existence of Red Blood Cells in Trapping Performance of Microbubbles by Acoustic Radiation Force

    NASA Astrophysics Data System (ADS)

    Masuda, Kohji; Nakamoto, Ryusuke; Watarai, Nobuyuki; Koda, Ren; Taguchi, Yuto; Kozuka, Teruyuki; Miyamoto, Yoshitaka; Kakimoto, Takashi; Enosawa, Shin; Chiba, Toshio

    2011-07-01

    We have proposed a method to control microbubbles by making use of acoustic radiation force, which is generated with acoustic propagation, to correspond to therapeutic applications of ultrasound. By preventing bubbles from passing through the desired target area, the local concentration of bubbles can be enhanced. However, we have never experimentally confirmed this phenomenon under in vivo conditions or close to those. Thus, we carried out an experiment to evaluate the trapping performance of bubbles using a suspension of red blood cells (RBCs) and an artificial blood vessel. By defining the trapping index to evaluate the amount of trapped microbubbles, we have confirmed that the trapping performance was enhanced according to the concentration of RBCs and the sound pressure, but not according to the central frequency of ultrasound. The results indicate that the existence of RBCs near microbubbles contributed to the increase in the size of aggregations propelled against the vessel wall.

  15. 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.

  16. Carboxylated nanodiamonds inhibit γ-irradiation damage of human red blood cells

    NASA Astrophysics Data System (ADS)

    Santacruz-Gomez, K.; Silva-Campa, E.; Melendrez-Amavizca, R.; Teran Arce, F.; Mata-Haro, V.; Landon, P. B.; Zhang, C.; Pedroza-Montero, M.; Lal, R.

    2016-03-01

    Nanodiamonds when carboxylated (cNDs) act as reducing agents and hence could limit oxidative damage in biological systems. Gamma (γ)-irradiation of whole blood or its components is required in immunocompetent patients to prevent transfusion-associated graft versus host disease (TA-GVHD). However, γ-irradiation of blood also deoxygenates red blood cells (RBCs) and induces oxidative damage, including abnormalities in cellular membranes and hemolysis. Using atomic force microscopy (AFM) and Raman spectroscopy, we examined the effect of cNDs on γ-irradiation mediated deoxygenation and morphological damage of RBCs. γ-Radiation induced several morphological phenotypes, including stomatocytes, codocytes and echinocytes. While stomatocytes and codocytes are reversibly damaged RBCs, echinocytes are irreversibly damaged. AFM images show significantly fewer echinocytes among cND-treated γ-irradiated RBCs. The Raman spectra of γ-irradiated RBCs had more oxygenated hemoglobin patterns when cND-treated, resembling those of normal, non-irradiated RBCs, compared to the non-cND-treated RBCs. cND inhibited hemoglobin deoxygenation and morphological damage, possibly by neutralizing the free radicals generated during γ-irradiation. Thus cNDs have the therapeutic potential to preserve the quality of stored blood following γ-irradiation.Nanodiamonds when carboxylated (cNDs) act as reducing agents and hence could limit oxidative damage in biological systems. Gamma (γ)-irradiation of whole blood or its components is required in immunocompetent patients to prevent transfusion-associated graft versus host disease (TA-GVHD). However, γ-irradiation of blood also deoxygenates red blood cells (RBCs) and induces oxidative damage, including abnormalities in cellular membranes and hemolysis. Using atomic force microscopy (AFM) and Raman spectroscopy, we examined the effect of cNDs on γ-irradiation mediated deoxygenation and morphological damage of RBCs. γ-Radiation induced several

  17. 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. PMID:26867209

  18. Immunoglobulin G-mediated regulation of the murine immune response to transfused red blood cells occurs in the absence of active immune suppression: implications for the mechanism of action of anti-D in the prevention of haemolytic disease of the fetus and newborn?

    PubMed Central

    Brinc, Davor; Le-Tien, Hoang; Crow, Andrew R; Siragam, Vinayakumar; Freedman, John; Lazarus, Alan H

    2008-01-01

    Anti-D has been widely and effectively used in Rhesus blood group D negative mothers for the prevention of haemolytic disease of the fetus and newborn; its mechanism of action however, often referred to as antibody-mediated immune suppression (AMIS), remains largely unresolved. We investigated, in a murine model, whether active immune suppression or clonal deletion mediated by anti-red blood cell (RBC) immunoglobulin G (IgG) could explain the phenomenon of AMIS. Transfusion of IgG-opsonized foreign RBCs (i.e. AMIS) strongly attenuated antibody responses compared to transfusion of untreated foreign RBCs. When the AMIS-mice were subsequently transfused with untreated RBCs, no immune suppression was observed at 5 and 35 days after AMIS induction; in fact, the mice responded to retransfusion with untreated RBCs in a manner that was characteristic of a secondary immune response. When IgG-opsonized RBCs were transfused concurrently with untreated RBCs, a dose-dependent reduction of the antibody response was observed. This work suggests that the attenuation of the antibody responsiveness by anti-RBC IgG is not associated with active immune suppression or clonal deletion at either the T-cell or B-cell level; rather, the effect appears more characteristic of B-cell unresponsiveness to IgG-opsonized RBCs. These results may have implications for the understanding of the mechanism of action of anti-D in haemolytic disease of the fetus and newborn. PMID:18266717

  19. 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

  20. Red blood cells do not contribute to removal of K+ released from exhaustively working forearm muscle.

    PubMed

    Maassen, N; Foerster, M; Mairbäurl, H

    1998-07-01

    K+ released from exercising muscle via K+ channels needs to be removed from the interstitium into the blood to maintain high muscle cell membrane potential and allow normal muscle contractility. Uptake by red blood cells has been discussed as one mechanism that would also serve to regulate red blood cell volume, which was found to be constant despite increased plasma osmolality and K+ concentration ([K+pl]). We evaluated exercise-related changes in [K+pl], pH, osmolality, mean cellular Hb concentration, cell water, and red blood cell K+ concentration during exhaustive handgrip exercise. Unidirectional 86Rb+ (K+) uptake by red blood cells was measured in media with elevated extracellular K+, osmolarity, and catecholamines to simulate particularly those exercise-related changes in plasma composition that are known to stimulate K+ uptake. During exercise [K+pl] increased from 4.4 +/- 0.7 to 7.1 +/- 0.5 mmol/l plasma water and red blood cell K+ concentration increased from 137.2 +/- 6.0 to 144.6 +/- 4.6 mmol/l cell water (P red blood cells was increased by approximately 20% on stimulation, caused by activation of the Na+-K+ pump and Na+-K+-2Cl- cotransport. Results indicate the K+ content of red blood cells did not change as cells passed the exhaustively exercising forearm muscle despite the elevated [K+pl]. The tendency for an increase in intracellular K+ concentration was due to a slight, although statistically not significant, decrease in red blood cell volume. K+ uptake, although elevated, was too small to move significant amounts of K+ into red blood cells. Our results suggest that red blood cells do not contribute to the removal of K+ released from muscle and do not regulate their volume by K+ uptake during exhaustive forearm exercise. PMID:9655793

  1. 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. PMID:26671221

  2. Viscoelastic properties of whole blood. Influence of fast sedimenting red blood cell aggregates.

    PubMed

    Schneditz, D; Rainer, F; Kenner, T

    1987-01-01

    Red blood cell (RBC) aggregation is known to be of deciding influence on erythrocyte sedimentation-rate (ESR) and on whole blood viscoelastic properties. The rheological behaviour of blood collected from a control-group with normal ESR is compared to the viscoelastic behaviour of blood collected from two groups with high to very high ESR, whose individuals are suffering from chronical polyarthritis and Morbus Bechterew, respectively. The rheological properties are evaluated by means of an oscillating-flow capillary-rheometer where the viscous (eta') and elastic (eta") component of the complex viscosity (eta) is measured at a constant frequency of 2 Hz. Correcting for the varying hematocrit of the different blood samples according to an exponential equation, the viscoelastic data are found to be elevated in the groups with high ESR. For the viscous properties this is only due to the increase of the plasma viscosity. A correction for the plasma viscosity, however, shows that the viscous properties at low shear- rates (2s-1) are significantly reduced, whereas elastic properties in a range of medium shear-rates (10s-1 to 50s-1) are significantly increased (P less than 0.001, t-test of Student). This result is discussed to be due to the high packing density of the RBC in fast sedimenting aggregates. High packing density reduces the effective volume of the RBC but increases the stiffness of the aggregates. PMID:3651579

  3. Current issues relating to the transfusion of stored red blood cells.

    PubMed

    Zimrin, A B; Hess, J R

    2009-02-01

    The development of blood storage systems allowed donation and transfusion to be separated in time and space. This separation has permitted the regionalization of donor services with subsequent economies of scale and improvements in the quality and availability of blood products. However, the availability of storage raises the question of how long blood products can and should be stored and how long they are safe and effective. The efficacy of red blood cells was originally measured as the increment in haematocrit and safety began with typing and the effort to reduce the risk of bacterial contamination. Appreciation of a growing list of storage lesions of red blood cells has developed with our increasing understanding of red blood cell physiology and our experience with red blood cell transfusion. However, other than frank haemolysis, rare episodes of bacterial contamination and overgrowth, the reduction of oxygen-carrying capacity associated with the failure of some transfused cells to circulate, and the toxicity of lysophospholipids released from membrane breakdown, storage-induced lesions have not had obvious correlations with safety or efficacy. The safety of red blood cell storage has also been approached in retrospective epidemiologic studies of transfused patients, but the results are frequently biased by the fact that sicker patients are transfused more often and blood banks do not issue blood products in a random order. Several large prospective studies of the safety of stored red blood cells are planned. PMID:19152602

  4. Role of transfused red blood cells for shock and coagulopathy within remote damage control resuscitation.

    PubMed

    Spinella, Philip C; Doctor, Allan

    2014-05-01

    The philosophy of damage control resuscitation (DCR) and remote damage control resuscitation (RDCR) can be summarized by stating that the goal is to prevent death from hemorrhagic shock by "staying out of trouble instead of getting out of trouble." In other words, it is preferred to arrest the progression of shock, rather than also having to reverse this condition after significant tissue damage and organ injury cascades are established. Moreover, to prevent death from exsanguination, a balanced approach to the treatment of both shock and coagulopathy is required. This was military doctrine during World War II, but seemed to be forgotten during the last half of the 20th century. Damage control resuscitation and RDCR have revitalized the approach, but there is still more to learn about the most effective and safe resuscitative strategies to simultaneously treat shock and hemorrhage. Current data suggest that our preconceived notions regarding the efficacy of standard issue red blood cells (RBCs) during the hours after transfusion may be false. Standard issue RBCs may not increase oxygen delivery and may in fact decrease it by disturbing control of regional blood flow distribution (impaired nitric oxide processing) and failing to release oxygen, even when perfusing hypoxic tissue (abnormal oxygen affinity). Standard issue RBCs may assist with hemostasis but appear to have competing effects on thrombin generation and platelet function. If standard issue or RBCs of increased storage age are not optimal, then are there alternatives that will allow for an efficacious and safe treatment of shock while also supporting hemostasis? Studies are required to determine if fresh RBCs less than 7 to 10 days provide an outcome advantage. A resurgence in the study of whole blood stored at 4°C for up to 10 days also holds promise. Two randomized controlled trials in humans have indicated that following transfusion with either whole blood stored at 4°C or platelets stored at 4

  5. 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

  6. Red blood cell (RBC) deformability, RBC aggregability and tissue oxygenation in hypertension.

    PubMed

    Cicco, G; Pirrelli, A

    1999-01-01

    Arterial hypertension could be considered a progressive ischaemic syndrome interesting the macro and the microcirculation. In order to improve the clinical and therapeutic approach to the treatment of arterial hypertension, research has centered on blood flow to evaluate the different components and their very intricate relationships influencing the micro- and the macrocirculation. Of course the main problem is to study the link between the blood flow and the peripheral tissue oxygenation. During hypertension very important alterations in rheological, mechanical and biochemical characteristics of erythrocytes and of blood flow have been shown. It is very relevant the increase in blood viscosity, the decrease in red blood cell (RBC) deformability, the formation of RBC "rouleaux" and RBC aggregates. These hemorheological determinants can favour an increase of peripheral resistances and of arterial blood pressure, causing or worsening hypertension, a decrease in oxygen transport to tissue and peripheral perfusion, a decrease of the active exchange surface area in the microvasculature, especially in complicated hypertension. We have studied 320 patients: 123 with Essential Hypertension (EH) (M 59, F 64 aged 50 +/- 25 years); 81 with Secondary Hypertension (SH) without associated other pathologies influencing hemorheology (M 42, F 39 aged 48 +/- 20 years); 116 SH with other pathologies or conditions associated influencing hemorheology such as: diabetes, lipoidoproteinosis, obesity, smoking, HD, elderly, etc. (M 48, F 68 aged 46 +/- 20 years). Using a Laser-assisted Optical Rotational Red Cell Analyzer (LORCA) acc. to Hardeman (1994) we studied Elongation Index (EI) and aggregation kinetics of red blood cells in these patients. We also evaluated TcpO2 and TcpCO2 using a transcutaneous oxymeter (Microgas 7650, Kontron Instruments). In hypertensives we found a decrease in erythrocyte deformability (evaluated with EI), in erythrocyte aggregation time, a fibrinogenaemia

  7. P2X and P2Y receptor signaling in red blood cells

    PubMed Central

    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. PMID:26579528

  8. 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. PMID:26684218

  9. 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.

  10. Effect of Irradiation on Microparticles in Red Blood Cell Concentrates.

    PubMed

    Cho, Chi Hyun; Yun, Seung Gyu; Koh, Young Eun; Lim, Chae Seung

    2016-07-01

    Changes in microparticles (MP) from red blood cell (RBC) concentrates in the context of irradiation have not been investigated. The aim of this study was to evaluate how irradiation affects the number of MPs within transfusion components. Twenty RBC concentrates, within 14 days after donation, were exposed to gamma rays (dose rate: 25 cGy) from a cesium-137 irradiator. Flow cytometry was used to determine the numbers of MPs derived from RBC concentrates before and 24 hr after irradiation. The mean number of MPs (±standard deviation) in RBC concentrates was 21.9×10⁹/L (±22.7×10⁹/L), and the total number of MPs ranged from 2.6×10⁹/L to 96.9×10⁹/L. The mean number of MPs increased to 22.6×10⁹/L (±31.6×10⁹/L) after irradiation. Before irradiation, the CD41-positive and CD235a-positive MPs constituted 9.5% (1.0×10⁹/L) and 2.2% (263×10⁶/L) of total MPs, respectively. After irradiation, CD41-positive MPs increased to 12.1% (1.5×10⁹/L) (P=0.014), but the CD235a-positive MPs decreased to 2.0% (214×10⁶/L) of the total MPs (P=0.369). Irradiation increases the number of CD41-positive MPs within RBC concentrates, suggesting the irradiation of RBC concentrates could be associated with thrombotic risk of circulating blood through the numerical change. PMID:27139610

  11. Effect of Irradiation on Microparticles in Red Blood Cell Concentrates

    PubMed Central

    Cho, Chi Hyun; Yun, Seung Gyu; Koh, Young Eun

    2016-01-01

    Changes in microparticles (MP) from red blood cell (RBC) concentrates in the context of irradiation have not been investigated. The aim of this study was to evaluate how irradiation affects the number of MPs within transfusion components. Twenty RBC concentrates, within 14 days after donation, were exposed to gamma rays (dose rate: 25 cGy) from a cesium-137 irradiator. Flow cytometry was used to determine the numbers of MPs derived from RBC concentrates before and 24 hr after irradiation. The mean number of MPs (±standard deviation) in RBC concentrates was 21.9×109/L (±22.7×109/L), and the total number of MPs ranged from 2.6×109/L to 96.9×109/L. The mean number of MPs increased to 22.6×109/L (±31.6×109/L) after irradiation. Before irradiation, the CD41-positive and CD235a-positive MPs constituted 9.5% (1.0×109/L) and 2.2% (263×106/L) of total MPs, respectively. After irradiation, CD41-positive MPs increased to 12.1% (1.5×109/L) (P=0.014), but the CD235a-positive MPs decreased to 2.0% (214×106/L) of the total MPs (P=0.369). Irradiation increases the number of CD41-positive MPs within RBC concentrates, suggesting the irradiation of RBC concentrates could be associated with thrombotic risk of circulating blood through the numerical change. PMID:27139610

  12. Determination of Fc function with frozen red blood cells.

    PubMed

    Gurevich, V; Bertolini, J; Lyons, K

    2006-09-01

    The Fc function of immunoglobulins is commonly determined by an assay based on monitoring immunoglobulin induced, complement mediated red cell lysis. This assay requires a continuous source of fresh red cells. We have shown that the assay can be successfully performed with frozen red cells. The possibility of access to a stored standard stock of red cells will improve the convenience of performing the assay and could contribute to improved assay reproducibility. PMID:16500112

  13. Effect of Hydroperoxides on Red Blood Cell Membrane Mechanical Properties

    PubMed Central

    Hale, John P.; Winlove, C. Peter; Petrov, Peter G.

    2011-01-01

    We investigate the effect of oxidative stress on red blood cell membrane mechanical properties in vitro using detailed analysis of the membrane thermal fluctuation spectrum. Two different oxidants, the cytosol-soluble hydrogen peroxide and the membrane-soluble cumene hydroperoxide, are used, and their effects on the membrane bending elastic modulus, surface tension, strength of confinement due to the membrane skeleton, and 2D shear elastic modulus are measured. We find that both oxidants alter significantly the membrane elastic properties, but their effects differ qualitatively and quantitatively. While hydrogen peroxide mainly affects the elasticity of the membrane protein skeleton (increasing the membrane shear modulus), cumene hydroperoxide has an impact on both membrane skeleton and lipid bilayer mechanical properties, as can be seen from the increased values of the shear and bending elastic moduli. The biologically important implication of these results is that the effects of oxidative stress on the biophysical properties, and hence the physiological functions, of the cell membrane depend on the nature of the oxidative agent. Thermal fluctuation spectroscopy provides a means of characterizing these different effects, potentially in a clinical milieu. PMID:22004746

  14. Characterization of Red Blood Cells with Multiwavelength Transmission Spectroscopy

    PubMed Central

    Serebrennikova, Yulia M.; Huffman, Debra E.; Garcia-Rubio, Luis H.

    2015-01-01

    Multiwavelength transmission (MWT) spectroscopy was applied to the investigation of the morphological parameters and composition of red blood cells (RBCs). The MWT spectra were quantitatively analyzed with a Mie theory based interpretation model modified to incorporate the effects of the nonsphericity and orientation of RBCs. The MWT spectra of the healthy and anemic samples were investigated for the RBC indices in open and blinded studies. When MWT performance was evaluated against a standard reference system, very good agreement between two methods, with R2 > 0.85 for all indices studied, was demonstrated. The RBC morphological parameters were used to characterize three types of anemia and to draw an association between RBC morphology and anemia severity. The MWT spectra of RBCs infected with malaria parasite Plasmodium falciparum at different life cycle stages were analyzed for RBC morphological parameters. The changes in the RBC volume, surface area, aspect ratio, and hemoglobin composition were used to trace the morphological and compositional alterations in the infected RBCs occurring with parasites' development and to provide insights into parasite-host interactions. The MWT method was shown to be reliable for determination of the RBC morphological parameters and to be valuable for identification of the RBC pathologic changes and disease states. PMID:25654099

  15. Characterization of red blood cells with multiwavelength transmission spectroscopy.

    PubMed

    Serebrennikova, Yulia M; Huffman, Debra E; Garcia-Rubio, Luis H

    2015-01-01

    Multiwavelength transmission (MWT) spectroscopy was applied to the investigation of the morphological parameters and composition of red blood cells (RBCs). The MWT spectra were quantitatively analyzed with a Mie theory based interpretation model modified to incorporate the effects of the nonsphericity and orientation of RBCs. The MWT spectra of the healthy and anemic samples were investigated for the RBC indices in open and blinded studies. When MWT performance was evaluated against a standard reference system, very good agreement between two methods, with R (2) > 0.85 for all indices studied, was demonstrated. The RBC morphological parameters were used to characterize three types of anemia and to draw an association between RBC morphology and anemia severity. The MWT spectra of RBCs infected with malaria parasite Plasmodium falciparum at different life cycle stages were analyzed for RBC morphological parameters. The changes in the RBC volume, surface area, aspect ratio, and hemoglobin composition were used to trace the morphological and compositional alterations in the infected RBCs occurring with parasites' development and to provide insights into parasite-host interactions. The MWT method was shown to be reliable for determination of the RBC morphological parameters and to be valuable for identification of the RBC pathologic changes and disease states. PMID:25654099

  16. Ratio of Spleen Diameter to Red Blood Cell Distribution Width

    PubMed Central

    Balaban, Daniel Vasile; Popp, Alina; Lungu, Andrei Marian; Costache, Raluca Simona; Anca, Ioana Alina; Jinga, Mariana

    2015-01-01

    Abstract Celiac disease (CD) is currently considerably underdiagnosed, setting the need for developing tools to select patients with probability of CD, who warrant further testing. Red blood cell distribution width (RDW) has been shown in previous studies to be a sensitive predictor for CD, but it lacks specificity. Splenic hypotrophy is also noted frequently in celiac patients. Our aim was to evaluate if spleen diameter to RDW ratio can be used as an indicator for CD. We evaluated 15 newly diagnosed CD patients, 52 patients with inflammatory bowel disease, and 35 patients with irritable bowel syndrome (IBS). We evaluated the differences in spleen diameter, RDW, and their ratio among the four groups. Two-thirds of the CD patients had elevated RDW, compared to 9% in the IBS group. A small spleen was seen in 80% of the celiacs, compared to 21.9% in the ulcerative colitis group, 10% in the Crohn disease group, and 9% in the IBS group. A spleen diameter to RDW ratio under 6 had a sensitivity of 73.3% and specificity of 88.5% in predicting CD, with an AUROC of 0.737. Spleen diameter to RDW ratio is a simple, widely available score, which can be used to select adult patients with probability of CD. PMID:25881851

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

    PubMed

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

    2013-09-01

    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. PMID:24010653

  18. 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

  19. 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.

  20. IMAGING RED BLOOD CELL DYNAMICS BY QUANTITATIVE PHASE MICROSCOPY

    PubMed Central

    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. PMID:18387320

  1. Harmless Pregnancy-Induced Warm Autoantibodies to Red Blood Cells

    PubMed Central

    Sürücü, Gülüstan; Mayer, Beate; Märzacker, Anneliese; Yürek, Salih; Salama, Abdulgabar

    2015-01-01

    Summary Background There is little information concerning the development and significance of autoantibodies (aab) to red blood cells (RBCs) during pregnancy. Methods Unselected pregnant women were routinely screened for the presence of unexpected antibodies to RBCs using standard techniques. Results Between 2009 and 2013, 153,612 pregnant women were tested. The antibody screening test was positive in 1,721 women (1.12%). In 1,602 (1.04%) cases, immune and/or non-immune alloantibodies and cold-reactive aab were detected, whereas warm-reactive aab were found in 119 women (0.08%). In almost all cases, warm-reactive aab belonged to the IgG class. No evidence of the presence of significant haemolysis in affected women was observed. Conclusion Pregnant women may rarely develop aab to RBCs, which do not appear to cause haemolytic anaemia. Further clarification is required on the reasons behind the development of these aab and their clinical insignificance. PMID:26696801

  2. 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. PMID:26706720

  3. Mechanical response of red blood cells entering a constriction.

    PubMed

    Zeng, Nancy F; Ristenpart, William D

    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 a microfluidic device and used high speed video to visualize and track the flow behavior of more than 4400 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 present detailed statistical analyses on the dynamics of each motion and demonstrate that the behavior is highly sensitive to the location of the RBC within the channel. We further demonstrate that the observed tumbling, twisting, and rolling rotations can be rationalized qualitatively in terms of rigid body mechanics. The detailed experimental statistics presented here should serve as a useful resource for modeling of RBC behavior under physiologically important flow conditions. PMID:25553197

  4. Interactions between earthworm hemolysins and sheep red blood cell membranes.

    PubMed

    Roch, P; Canicatti, C; Valembois, P

    1989-08-01

    The hemolytic activity exhibited by the coelomic fluid of the Annelid Eisenia fetida andrei is mediated by two lipoproteins of mass 40 and 45 kDa, each of them capable of hemolysis. Such an activity is not inhibited by zymosan, inulin or lipopolysaccharide (LPS), nor by hydrazine or methylamine, suggesting that earthworm hemolysins are not related to C3 or C3b complement components. Among the membrane lipids tested (phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, sphingomyelin and cholesterol) only sphingomyelin inhibited hemolysis. The analysis of E.f. andrei proteins bound to sphingomyelin microvesicles, as well as to sheep red blood cell (SRBC) membranes, revealed a polymerization of E.f. andrei 40 kDa and/or 45 kDa hemolysins. Consequently, sphingomyelin appears a likely candidate for hemolytic complex receptor. Electron microscopy observations suggested that the polymerization causes an open channel through the lipid bilayer. As demonstrated using metal ions, heparin, chondroitin sulfate, poly(L-lysine) and protamine chloride, the mode of action of earthworm hemolytic complex is not analogous to that of C9 or perforine. PMID:2758056

  5. Of macrophages and red blood cells; a complex love story.

    PubMed

    de Back, Djuna Z; Kostova, Elena B; van Kraaij, Marian; van den Berg, Timo K; van Bruggen, Robin

    2014-01-01

    Macrophages tightly control the production and clearance of red blood cells (RBC). During steady state hematopoiesis, approximately 10(10) RBC are produced per hour within erythroblastic islands in humans. In these erythroblastic islands, resident bone marrow macrophages provide erythroblasts with interactions that are essential for erythroid development. New evidence suggests that not only under homeostasis but also under stress conditions, macrophages play an important role in promoting erythropoiesis. Once RBC have matured, these cells remain in circulation for about 120 days. At the end of their life span, RBC are cleared by macrophages residing in the spleen and the liver. Current theories about the removal of senescent RBC and the essential role of macrophages will be discussed as well as the role of macrophages in facilitating the removal of damaged cellular content from the RBC. In this review we will provide an overview on the role of macrophages in the regulation of RBC production, maintenance and clearance. In addition, we will discuss the interactions between these two cell types during transfer of immune complexes and pathogens from RBC to macrophages. PMID:24523696

  6. 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.

  7. Cytoskeletal control of the red-blood cell membrane

    NASA Astrophysics Data System (ADS)

    Gov, Nir; Safran, Sam

    2004-03-01

    We have shown (Physical Review Letters, 90, 228101 (2003)) that the thermal fluctuations of red blood cells can be accounted for by a model of a nearly-free, but confined bilayer membrane with a finite tension; both the confinement and tension arise from the coupling of the membrane with the cytoskeleton. Recently, we have shown that these relatively gentle effects of the cytoskeleton-membrane couplings on the membrane fluctuations are due to the dilute nature of the coupling molecules. To quantify this, we predict the fluctuation amplitude for a microscopic model of the inhomogeneous coupling of a fluid membrane and a fixed cytoskeleton. The coupling is modeled as periodic and harmonic, and we consider the linear response of the membrane. We find that there is indeed, an effective surface tension and confinement of such a membrane, in accord with our phenomenological model, and relate these quantities to the strength and periodicity of the microscopic coupling. We also find, surprisingly, that the membrane can develop a spontaneous breaking of the cytoskeleton symmetry, at low confinements. Finally we address the role of ATP activity on the cytoskeleton-driven fluctuations and the equilibrium shape of the cell. We examine in detail the role of spectrin disconnections as the main ATP-activated network defects on the global cell shape and membrane fluctuations.

  8. Loss of deformability of malaria-infected red blood cells

    NASA Astrophysics Data System (ADS)

    Hosseini, S. Majid; Feng, James

    2012-11-01

    The pathogenesis of malaria is largely due to stiffening of the infected red blood cells (RBCs). Contemporary understanding ascribes the loss of RBC deformability to a 10-fold increase in membrane stiffness caused by extra cross-linking in the spectrin network. Local measurements by micropipette aspiration, however, have reported only an increase of 3-fold in the shear modulus. We believe the discrepancy stems from the rigid parasite particles inside infected cells, and have carried out numerical simulations to demonstrate this mechanism. The cell membrane is represented by a set of discrete particles connected by linearly elastic springs. The cytosol is modeled as a homogeneous Newtonian fluid, and discretized by particles as in standard smoothed particle hydrodynamics. The malaria parasite is modeled as an aggregate of particles constrained to rigid-body motion. We simulate RBC stretching tests by optical tweezers in three dimensions. The results demonstrate that the presence of a sizeable parasite greatly reduces the ability of RBCs to deform under stretching. With the solid inclusion, the observed loss of deformability can be predicted quantitatively using the local membrane elasticity measured by micropipettes.

  9. 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

  10. 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. PMID:26701327

  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. Density increment and decreased survival of rat red blood cells induced by cadmium

    SciTech Connect

    Kunimoto, M.; Miura, T.

    1986-01-01

    Male Wistar rats were injected with CdCl/sub 2/ subcutaneously to examine in vivo effects of Cd on density and survival of red blood cells. During the 7 days after administration of 1.0 mg Cd/kg, the following sequence of events occurred: (1) a progressive increase in the amount of more dense red blood cells concomitant with a decrease in that of light red blood cells from the first to the third day; (2) an increase in the spleen weight at the third day; (3) a decrease in the hematocrit value and an increase in the amount of light red blood cells at the fifth day; and (4) a recovery of the hematocrit value at the seventh day. Five days after administration, the hematocrit value decreased in a dose-dependent mode and the decrease was significant at the 1% level at 1.0 and 1.5 mg Cd/kg. A highly significant splenomegaly was also observed at 0.5 to 1.5 mg Cd/kg. In order to label red blood cells in vivo, (/sup 3/H) diisopropylfluorophosphate ((/sup 3/H)DFP) was injected into rats. At Day 11, Cd at either 0.5 or 1.0 mg/kg was administered to (/sup 3/H)DFP-prelabeled animals. Cd administration accelerated /sup 3/H-labeled red cell clearance from the blood. Six days after Cd administration, the radioactivity of red blood cells was 76 and 68% of the control at 0.5 and 1.0 mg Cd/kg, respectively. In vitro treatment of rat red density and accelerated in vivo clearance of red blood cells from the recipient circulation. These results show that Cd at low dose can cause anemia by increasing red cell density and by accelerating red cell sequestration, presumably in the spleen.

  13. Perturbation of red blood cell flow in small tubes by white blood cells.

    PubMed

    Thompson, T N; La Celle, P L; Cokelet, G R

    1989-02-01

    The flow of blood in the microcirculation is facilitated by the dynamic reduction in viscosity (Fahraeus-Lindquist effect) resulting from the axial flow of deforming erythrocytes (RBCs) and from the decrease in the ratio of cell to vessel diameter. RBC velocity exceeds that of average fluid velocity; however the slower moving white blood cells (WBC) perturb flow velocity and the ratio of cell to vessel diameter by obstructing red cell flow through formation of "trains" of red cells collecting behind the white cell. This effect of white cells was studied quantitatively in a model in vitro tubes less than 10 microns in diameter with the demonstration that flow resistance increases linearly with white cell numbers up to 1,000 WBC/mm3 at tube hematocrit of 17.7%. The increase in resistance exceeds the flow resistance of WBC and appears to relate directly to train formation. A mechanical model of train formation developed to predict WBC influence in flow resistance over the range of WBC studied reasonably fits observed WBC effects. PMID:2928089

  14. Carboxylated nanodiamonds inhibit γ-irradiation damage of human red blood cells.

    PubMed

    Santacruz-Gomez, K; Silva-Campa, E; Melendrez-Amavizca, R; Teran Arce, F; Mata-Haro, V; Landon, P B; Zhang, C; Pedroza-Montero, M; Lal, R

    2016-04-01

    Nanodiamonds when carboxylated (cNDs) act as reducing agents and hence could limit oxidative damage in biological systems. Gamma (γ)-irradiation of whole blood or its components is required in immunocompetent patients to prevent transfusion-associated graft versus host disease (TA-GVHD). However, γ-irradiation of blood also deoxygenates red blood cells (RBCs) and induces oxidative damage, including abnormalities in cellular membranes and hemolysis. Using atomic force microscopy (AFM) and Raman spectroscopy, we examined the effect of cNDs on γ-irradiation mediated deoxygenation and morphological damage of RBCs. γ-Radiation induced several morphological phenotypes, including stomatocytes, codocytes and echinocytes. While stomatocytes and codocytes are reversibly damaged RBCs, echinocytes are irreversibly damaged. AFM images show significantly fewer echinocytes among cND-treated γ-irradiated RBCs. The Raman spectra of γ-irradiated RBCs had more oxygenated hemoglobin patterns when cND-treated, resembling those of normal, non-irradiated RBCs, compared to the non-cND-treated RBCs. cND inhibited hemoglobin deoxygenation and morphological damage, possibly by neutralizing the free radicals generated during γ-irradiation. Thus cNDs have the therapeutic potential to preserve the quality of stored blood following γ-irradiation. PMID:26972691

  15. Measuring electrical and mechanical properties of red blood cells with a double optical tweezers

    NASA Astrophysics Data System (ADS)

    Fontes, Adriana; Fernandes, Heloise P.; Barjas-Castro, Maria L.; de Thomaz, André A.; Pozzo, Liliana d. Y.; Barbosa, Luiz C.; Cesar, Carlos L.

    2006-08-01

    The fluid lipid bilayer viscoelastic membrane of red blood cells (RBC) contains antigen glycolproteins and proteins which can interact with antibodies to cause cell agglutination. This is the basis of most of the immunohematologic tests in blood banks and the identification of the antibodies against the erythrocyte antigens is of fundamental importance for transfusional routines. The negative charges of the RBCs creates a repulsive electric (zeta) potential between the cells and prevents their aggregation in the blood stream. The first counterions cloud strongly binded moving together with the RBC is called the compact layer. This report proposes the use of a double optical tweezers for a new procedure for measuring: (1) the apparent membrane viscosity, (2) the cell adhesion, (3) the zeta potential and (4) the compact layer's size of the charges formed around the cell in the electrolytic solution. To measure the membrane viscosity we trapped silica beads strongly attached to agglutinated RBCs and measured the force to slide one RBC over the other as a function of the relative velocity. The RBC adhesion was measured by slowly displacing two RBCs apart until the disagglutination happens. The compact layer's size was measured using the force on the silica bead attached to a single RBC in response to an applied voltage and the zeta potential was obtained by measuring the terminal velocity after releasing the RBC from the optical trap at the last applied voltage. We believe that the methodology here proposed can improve the methods of diagnosis in blood banks.

  16. The distribution of serum folate concentration and red blood cell indices in alcoholics.

    PubMed

    Cylwik, Bogdan; Naklicki, Marcin; Gruszewska, Ewa; Szmitkowski, Maciej; Chrostek, Lech

    2013-01-01

    Chronic alcohol consumption leads to malnutrition and to the deficiency of many vitamins. One of the most important is folate deficiency. Folate deficiency disrupts the process of hematopoiesis, which can be evaluated by the changes of red cell indices. The aim of this study was to determine the hematological disturbances by the measurement of red blood cell indices in a Polish population of chronic alcoholics according to folate status. We studied 80 consecutive chronic alcoholic men and 30 healthy controls. Patients were divided into 2 groups according to the folate concentration. The serum folate and vitamin B12 concentration and the blood count were determined. We have shown that the serum folate concentration was decreased in 40% of alcoholics, but there was no folate deficiency and the level of vitamin B12 was normal. There was no correlation between folate, vitamin B12 and hematological indices. We have observed that most hematological parameters (Hb, RBCs, and Hct) in alcoholics were decreased and only two of them (MCV and MCHC) were increased in comparison with the controls. We observed no significant correlation between the RBCs indices and the weekly alcohol intake, but the correlation between RBCs, Hb, Hct and the duration of dependence have been shown. We concluded that, there is no folate deficiency in the Polish alcoholic population but the abusers with low folate levels may already have some RBCs indices affected. It means that the Polish alcoholic population consumes a sufficient amount of vitamins, which prevents the occurrence of hematological disturbances. PMID:23535533

  17. 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

    2016-05-01

    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. PMID:26984406

  18. Red blood cell sodium transport in patients with cirrhosis.

    PubMed

    Henriksen, Ulrik Lütken; Kiszka-Kanowitz, Marianne; Bendtsen, Flemming; Henriksen, Jens H

    2016-09-01

    Patients with advanced cirrhosis have abnormal sodium homoeostasis. The study was undertaken to quantify the sodium transport across the plasma membrane of red blood cells (RBC) in patients with cirrhosis. RBC efflux and influx of sodium were studied in vitro with tracer (22) Na(+) according to linear kinetics in 24 patients with cirrhosis and 14 healthy controls. The sodium efflux was modified by ouabain (O), furosemide (F) and a combination of O and F (O + F). RBC sodium was significantly decreased (4·6 versus control 6·3 mmol l(-1) , P<0·001) and directly related to serum sodium (r = 0·57, P<0·05). The RBC fractional sodium efflux was higher in patients with cirrhosis (+46%, P<0·01) compared to controls. Inhibition in both high (145 mmol l(-1) )- and low (120 mmol l(-1) )-sodium buffers showed that the F-insensitive sodium efflux was twice as high in cirrhosis as in controls (P = 0·03-0·007), especially the O-sensitive, F-insensitive efflux was increased (+ 225%, P = 0·01-0·006). Fractional F-sensitive transport was normal in cirrhosis. RBC sodium influx was largely normal in cirrhosis. In conclusion, RBC sodium content is reduced in patients with cirrhosis with a direct relation to serum sodium. Increased RBC sodium efflux is especially related to ouabain-sensitive, furosemide-insensitive transport and thus most likely due to upregulated activity of the sodium-potassium pump. The study gives no evidence to an altered intracellular/extracellular sodium ratio or to a reduced fractional furosemide-sensitive sodium transport in cirrhosis. PMID:26016736

  19. 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. PMID:23402665

  20. Recurrent gastrointestinal bleeding diagnosed by delayed scintigraphy with Tc-99m-labeled red blood cells.

    PubMed

    Nwakanma, Lois; Meyerrose, Gary; Kennedy, Shalyn; Rakvit, Ariwan; Bohannon, Todd; Silva, Micheal

    2003-08-01

    A 56-year-old woman presented with bright-red blood from the rectum. Esophagogastroduodenoscopy revealed mild gastritis. Colonoscopy demonstrated diverticulosis without active bleeding, and in vitro tagged red blood cell scintigraphy was unremarkable. There was no further evidence of bleeding and the patient was discharged home. The patient returned with recurrent bright-red blood from the rectum. Although delayed scintigraphic images seldom demonstrate the site of bleeding, delayed images at 12 hours demonstrated active bleeding near the hepatic flexure in this patient. This was confirmed with selective mesenteric angiography, and was treated with coil embolization of the tertiary branches of the right middle colic artery. PMID:12897664

  1. 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.

  2. 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. PMID:16051738

  3. Red blood cell aggregation and blood viscosity in an isolated heart preparation.

    PubMed

    Charansonney, O; Mouren, S; Dufaux, J; Duvelleroy, M; Vicaut, E

    1993-01-01

    We studied the effects of moderate changes in red blood cell RBC aggregation on blood flow in the vasodilated vascular bed of an isolated rat heart. We compared a non-aggregating RBC suspension (in Krebs-albumin medium) with RBC suspensions in 1% and 2% Dextran 70 (MW 70000), exhibiting two different degrees of moderate aggregation. Degrees of aggregation were precisely estimated by in vitro laser aggregometry. Each heart was perfused by the non-aggregating RBC suspension and by one aggregating RBC suspensions. Blood flow was measured in a range of perfusion pressure from 40 to 80 mm Hg. For the three RBC suspensions, linear pressure/flow relationships were found. From the comparison between the pressure/flow relationships obtained with Krebs albumin medium and either 1% or 2% Dextran, it was possible to compare in vivo the contribution of RBC to the viscosity (i.e., the relative apparent viscosity) in the 2 aggregating RBC suspensions with that of the non-aggregating RBC suspension. The contribution of RBC to the viscosity was found to be 20% to 25% lower in the 1% RBC suspension than in the non-aggregating RBC suspension. With 2% Dextran which induced a higher degree of aggregation no differences were found between the relative apparent viscosities of the aggregating and the non-aggregating suspension. From the comparison between RBC in 1% Dextran and Krebs-albumin, we concluded that in vivo a moderate RBC aggregation reduces viscous resistance due to the presence of blood in a vascular network. Since no more effect of RBC aggregation per se was found when the degree of aggregation was higher (with RBC in 2% Dextran), this suggests that, in this case, aggregation induces opposite effects along the myocardial vascular network which cancel each other out, thus inducing a nil net balance. PMID:7690613

  4. 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.

  5. Prevention of growth of Yersinia enterocolitica in blood by polyester fiber filtration.

    PubMed

    Wenz, B; Burns, E R; Freundlich, L F

    1992-09-01

    The ability of polyester white cell-reduction blood filters to prevent the growth of Yersinia enterocolitica in units of donated blood was studied. Sixteen units of freshly drawn blood were inoculated with 10, 50, 100, or 150 colony-forming units (CFU) per mL of a clinical isolate of Y. enterocolitica (serotype O:3). The units were subsequently fractionated into red cell concentrate and resuspended in AS-1 or AS-3 solution. One-half of the red cell concentrates in each solution were filtered within 15 hours of phlebotomy and stored for 42 days. The remaining units served as unfiltered controls. Bacterial growth was monitored by weekly cultures and, on the last storage day, by the presence of endotoxin and the formation of methemoglobin. One hundred twelve primary cultures (560 plates) were performed. Units collected in AS-1 and filtered remained sterile when initially inoculated with 50 CFU or less. Filtered units spiked with 100 CFU or less and collected in AS-3 remained sterile throughout their shelf life. All unfiltered units supported bacterial growth and the formation of endotoxin and methemoglobin. The filtration of freshly donated blood proves to limit the growth of Y. enterocolitica in red cell components. PMID:1519329

  6. AMERICAN NATIONAL RED CROSS BLOOD PROGRAM AWARD GROUP - LEFT TO RIGHT - SEATED - JOHN S BROWN - MISS

    NASA Technical Reports Server (NTRS)

    1956-01-01

    AMERICAN NATIONAL RED CROSS BLOOD PROGRAM AWARD GROUP - LEFT TO RIGHT - SEATED - JOHN S BROWN - MISS ELEANOR KIPLINGER - DR SHARP - JESSIE SHEWARD - DR VICTORY - FIRST ROW - GORDON ROMIG - ROBERT BRIGADOI - MIKE VACCARO - ALFRED VALERINO -

  7. 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.

  8. Photoacoustic assessment of oxygen saturation: effect of red blood cell aggregation

    NASA Astrophysics Data System (ADS)

    Hysi, Eno; Saha, Ratan K.; Kolios, Michael C.

    2013-03-01

    The simultaneous photoacoustic assessment of oxygen saturation and red blood cell aggregation is presented. Aggregation was induced on porcine red blood cells using Dextran-70 at multiple hematocrit levels. Samples were exposed to 750 nm and 1064 nm for each hematocrit and aggregate size in order to compute the oxygen saturation. As the size of the aggregate increased, the photoacoustic signal amplitude increased monotonically. The same trend was observed for increasing hematocrit at each aggregation level. The oxygen saturation of aggregated samples was 30% higher than non-aggregated samples at each hematocrit level. This suggests that the presence of red blood cell aggregates impairs the release of oxygen to the surrounding environment. Such a result has important implications for detecting red blood cell aggregation non-invasively and making clinical decisions based on the simulatenous assessment of oxygen saturation.

  9. Integration of red cell genotyping into the blood supply chain: a population-based study

    PubMed Central

    Flegel, Willy A; Gottschall, Jerome L; Denomme, Gregory A

    2015-01-01

    Background When problems with compatibility arise, transfusion services often perform time-consuming serologic testing to locate antigen-negative red cell units for safe transfusion. New technologies enabled red cell genotyping for all clinically relevant blood group antigens. We performed mass-scale genotyping and provided access to a large red cell database to meet the demand for antigen-negative red cell units beyond ABO and Rh. Methods A red cell genotype database was established in 2010. Hospitals were given online access to a web-based antigen query portal in 2013 to find antigen-negative units in their inventories. Findings Genotype data were analyzed for 43,066 blood donors covering a set of 42 clinically relevant red cell antigens. Requests were filled for 5661 of 5672 patient encounters (99.8%) requiring antigen-negative red cell units in a multi-ethnic and multi-racial population. Red cell genotyping met the demand for antigen-negative blood in 5339 of 5672 (95%) patient encounters, while 333 remaining requests were filled using serologic data. In a pilot phase, seven community and rural transfusion services searched their local inventories using an online antigen query portal. Interpretation Red cell genotyping has the potential to transform the way antigen-negative red cell units are provided. An antigen query portal may reduce the need to ship blood or perform serologic screening. The wealth of genotype data, easily accessible online, facilitates the supply of affordable antigen-negative red cell units for patient safety. Physicians may recognize these new efficiencies for patient transfusion support. Funding BloodCenter of Wisconsin Diagnostic Laboratories Strategic Initiative and the NIH Clinical Center Intramural Research Program. PMID:26207259

  10. 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.

  11. 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.

  12. Low Red Blood Cell Vitamin C Concentrations Induce Red Blood Cell Fragility: A Link to Diabetes Via Glucose, Glucose Transporters, and Dehydroascorbic Acid

    PubMed Central

    Tu, Hongbin; Li, Hongyan; Wang, Yu; Niyyati, Mahtab; Wang, Yaohui; Leshin, Jonathan; Levine, Mark

    2015-01-01

    Strategies to prevent diabetic microvascular angiopathy focus on the vascular endothelium. Because red blood cells (RBCs) are less deformable in diabetes, we explored an original concept linking decreased RBC deformability to RBC ascorbate and hyperglycemia. We characterized ascorbate concentrations from human and mouse RBCs and plasma, and showed an inverse relationship between RBC ascorbate concentrations and deformability, measured by osmotic fragility. RBCs from ascorbate deficient mice were osmotically sensitive, appeared as spherocytes, and had decreased β-spectrin. These aberrancies reversed with ascorbate repletion in vivo. Under physiologic conditions, only ascorbate's oxidation product dehydroascorbic acid (DHA), a substrate for facilitated glucose transporters, was transported into mouse and human RBCs, with immediate intracellular reduction to ascorbate. In vitro, glucose inhibited entry of physiologic concentrations of dehydroascorbic acid into mouse and human RBCs. In vivo, plasma glucose concentrations in normal and diabetic mice and humans were inversely related to respective RBC ascorbate concentrations, as was osmotic fragility. Human RBC β-spectrin declined as diabetes worsened. Taken together, hyperglycemia in diabetes produced lower RBC ascorbate with increased RBC rigidity, a candidate to drive microvascular angiopathy. Because glucose transporter expression, DHA transport, and its inhibition by glucose differed for mouse versus human RBCs, human experimentation is indicated. PMID:26870799

  13. [Management of blood pressure for stroke prevention].

    PubMed

    Tanahashi, Norio

    2016-04-01

    Hypertension is a major risk factor for both cerebral infarction and intracerebral hemorrhage. The relationship between blood pressure (BP) and stroke risk is strong and continuous. Throughout the usual range of BPs, including the nonhypertensive range, the higher the BP is, the greater the risk of stroke. Regular BP screening and appropriate treatment of patients with hypertension, including life style modification and pharmacotherapy, are recommended. Patients who have hypertension should be treated with antihypertensive drugs to a target BP of < 140/90 mmHg. Successful reduction of BP is more important in reducing stroke risk than the choice of a specific agent, and treatment should be individualized on the basis of other patient characteristics and medication tolerance. In hypertensive patients with stroke, subjects to be treated with antihypertensive drugs and the target level of BP control are determined on the basis of clinical disease type, interval after onset, severity, age, and the use of antithrombotic. drugs. According to the guideline of the Japanese Society of Hypertension (JSH 2014), in the chronic phase of cerebral infarction, cerebral hemorrhage and subarachnoid hemorrhage, target BP should be < 140/ 90 mmHg. In patients with lacunar infarction, those taking antithrombotic drugs, cerebral hemorrhage and subarachnoid hemorrhage, a lower level, < 130/80 mmHg should be targeted if possible. Oral antihypertensive drugs such as Ca channel blockers, angiotensin-converting enzyme inhibitors, angiotensin II receptor blockers and diuretics are recommended for patients with stroke. PMID:27333760

  14. 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

  15. 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.

  16. A Red-Light Running Prevention System Based on Artificial Neural Network and Vehicle Trajectory Data

    PubMed Central

    Li, Pengfei; Li, Yan; Guo, Xiucheng

    2014-01-01

    The high frequency of red-light running and complex driving behaviors at the yellow onset at intersections cannot be explained solely by the dilemma zone and vehicle kinematics. In this paper, the author presented a red-light running prevention system which was based on artificial neural networks (ANNs) to approximate the complex driver behaviors during yellow and all-red clearance and serve as the basis of an innovative red-light running prevention system. The artificial neural network and vehicle trajectory are applied to identify the potential red-light runners. The ANN training time was also acceptable and its predicting accurate rate was over 80%. Lastly, a prototype red-light running prevention system with the trained ANN model was described. This new system can be directly retrofitted into the existing traffic signal systems. PMID:25435870

  17. 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

  18. Preoperative preparation of the patient with the abnormalities of red and white blood cells.

    PubMed

    Tomin, Dragica

    2011-01-01

    The complete peripheral blood count analysis including laboratory screening tests of haemostasis and coagulation should be done in every patient before surgery, in order to detect specific abnormalities for primary or secundary haematologic disorder. These abnormalities might be very important course of perioperative and postoperative complications. Anaemia is the most frequent haematologic abnormality seen during preoperative period. Therapy approach depends on the type and anaemia degree, and also on the type and time of surgery. If surgery is not urgent specific therapy according to the anaemia type (iron therapy, vitamin B12, folic acid, corticosteroids, recombinant erythropoietin) should be given in all anaemias with deficiency of iron, megaloblastic anaemias, acquired haemolytic anaemias and anaemias in end stage renal disease. Transfusion of red cells are most frequently given in patients with normovolemic anaemias with haemoglobin level of 10.0 g/dl and hematocrit of 0.30, but lower levels in haemodynamic stable patients. Venesections should be done in patients with erythrocytosis in order to reduce total red cell volume, but taking into account the perioperative bleeding. Patients with leukocyte abnormalities suspected on primary haematologic disorder need urgent haematologic diagnostic procedures. In patients with leucocytosis the actual level of neutropenia is the bigger problem than the level of leucocytosis. In those patients treatment generally involves preventing infections, managing of febrile neutropenia with broad spectrum antibiotics and antifungal drugs, treatment with recombinant granulocyte hematopoetic factor, rarely transfusions of granulocyte concentrates and intravenous immunoglobulins. PMID:21879654

  19. 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.

  20. Design of an automated algorithm for labeling cardiac blood pool in gated SPECT images of radiolabeled red blood cells

    SciTech Connect

    Hebert, T.J. |; Moore, W.H.; Dhekne, R.D.; Ford, P.V.; Wendt, J.A.; Murphy, P.H.; Ting, Y.

    1996-08-01

    The design of an automated computer algorithm for labeling the cardiac blood pool within gated 3-D reconstructions of the radiolabeled red blood cells is investigated. Due to patient functional abnormalities, limited resolution, and noise, certain spatial and temporal features of the cardiac blood pool that one would anticipate finding in every study are not present in certain frames or with certain patients. The labeling of the cardiac blood pool requires an algorithm that only relies upon features present in all patients. The authors investigate the design of a fully-automated region growing algorithm for this purpose.

  1. Banking of pluripotent adult stem cells as an unlimited source for red blood cell production: potential applications for alloimmunized patients and rare blood challenges.

    PubMed

    Peyrard, Thierry; Bardiaux, Laurent; Krause, Claire; Kobari, Ladan; Lapillonne, Hélène; Andreu, Georges; Douay, Luc

    2011-07-01

    The transfusion of red blood cells (RBCs) is now considered a well-settled and essential therapy. However, some difficulties and constraints still occur, such as long-term blood product shortage, blood donor population aging, known and yet unknown transfusion-transmitted infectious agents, growing cost of the transfusion supply chain management, and the inescapable blood group polymorphism barrier. Red blood cells can be now cultured in vitro from human hematopoietic, human embryonic, or human-induced pluripotent stem cells (hiPSCs). The highly promising hiPSC technology represents a potentially unlimited source of RBCs and opens the door to the revolutionary development of a new generation of allogeneic transfusion products. Assuming that in vitro large-scale cultured RBC production efficiently operates in the near future, we draw here some futuristic but realistic scenarios regarding potential applications for alloimmunized patients and those with a rare blood group. We retrospectively studied a cohort of 16,486 consecutive alloimmunized patients (10-year period), showing 1 to 7 alloantibodies with 361 different antibody combinations. We showed that only 3 hiPSC clones would be sufficient to match more than 99% of the 16,486 patients in need of RBC transfusions. The study of the French National Registry of People with a Rare Blood Phenotype/Genotype (10-year period) shows that 15 hiPSC clones would cover 100% of the needs in patients of white ancestry. In addition, one single hiPSC clone would meet 73% of the needs in alloimmunized patients with sickle cell disease for whom rare cryopreserved RBC units were required. As a result, we consider that a very limited number of RBC clones would be able to not only provide for the need for most alloimmunized patients and those with a rare blood group but also efficiently allow for a policy for alloimmunization prevention in multiply transfused patients. PMID:21377319

  2. 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

  3. Red blood cell membrane viscoelasticity, agglutination and zeta potential measurements with double optical tweezers

    NASA Astrophysics Data System (ADS)

    Fontes, Adriana; Fernandes, Heloise P.; Barjas-Castro, Maria L.; de Thomaz, André A.; de Ysasa Pozzo, Liliana; Barbosa, Luiz C.; Cesar, Carlos L.

    2006-02-01

    The red blood cell (RBC) viscoelastic membrane contains proteins and glycolproteins embedded in, or attached, to a fluid lipid bilayer and are negatively charged, which creates a repulsive electric (zeta) potential between the cells and prevents their aggregation in the blood stream. There are techniques, however, to decrease the zeta potential to allow cell agglutination which are the basis of most of the tests of antigen-antibody interactions in blood banks. This report shows the use of a double optical tweezers to measure RBC membrane viscosity, agglutination and zeta potential. In our technique one of the optical tweezers trap a silica bead that binds strongly to a RBC at the end of a RBCs rouleaux and, at the same time, acts as a pico-Newton force transducer, after calibration through its displacement from the equilibrium position. The other optical tweezers trap the RBC at the other end. To measure the membrane viscosity the optical force is measured as a function of the velocity between the RBCs. To measure the adhesion the tweezers are slowly displaced apart until the RBCs disagglutination happens. The RBC zeta potential is measured in two complimentary ways, by the force on the silica bead attached to a single RBC in response to an applied electric field, and the conventional way, by the measurement of terminal velocity of the RBC after released from the optical trap. These two measurements provide information about the RBC charges and, also, electrolytic solution properties. We believe this can improve the methods of diagnosis in blood banks.

  4. Thyroid hormone stimulation in vitro of red blood cell Ca2+-ATPase activity: interspecies variation.

    PubMed

    Davis, F B; Kite, J H; Davis, P J; Blas, S D

    1982-01-01

    In vitro susceptibility to thyroid hormone stimulation of membrane-associated Ca2+-ATPase activity has been examined in red blood cells from rat, rabbit, dog, monkey, and man. Monkey and human red cell Ca2+-ATPase activities responded comparably to 10(-10)M T4 or T3. Basal and thyroid hormone-stimulated Ca2+-ATPase activity in rabbit erythrocytes was four-fold higher than in primate red cells. Rat and dog red cell Ca2+-ATPase did not respond to iodothyronines in vitro. PMID:6459228

  5. 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. PMID:27185543

  6. 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

  7. 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.

  8. 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.

  9. Perioperative Red Blood Cell Transfusion: Harmful or Beneficial to the Patient?

    PubMed

    Meier, Jens; Müller, Markus M; Lauscher, Patrick; Sireis, Walid; Seifried, Erhard; Zacharowski, Kai

    2012-04-01

    Although the transfusion of red blood cells (RBCs) is safer than ever regarding infections, it is still associated with several adverse reactions and therefore should only be used on the basis of evidence-based triggers. However, prevention of RBC transfusion and subsequent substitution of blood losses with acellular solutions will inevitably result in dilutional anemia. Acute dilutional anemia can be compensated by the body over a wide range of hemoglobin concentrations without a critical restriction of tissue oxygenation. On the other hand, chronic anemia is known to be a potent cause of morbidity and mortality. As a consequence, the impact of perioperative anemia on mortality is difficult to describe, because anemia, as well as the transfusion of RBCs, can influence the clinical outcome. The resulting 'Gordian knot' cannot be cut easily, and this circumstance forces clinical physicians to make a daily trade-off between transfusion-associated and anemia-associated risks. This review focuses on the physiology of oxygen transport, the hazards of acute anemia, the hazards of RBC transfusion, and the literature putting these problems into perspective. PMID:22670127

  10. Ligation of Glycophorin A Generates Reactive Oxygen Species Leading to Decreased Red Blood Cell Function

    PubMed Central

    Khoory, Joseph; Estanislau, Jessica; Elkhal, Abdallah; Lazaar, Asmae; Melhorn, Mark I.; Brodsky, Abigail; Illigens, Ben; Hamachi, Itaru; Kurishita, Yasutaka; Ivanov, Alexander R.; Shevkoplyas, Sergey; Shapiro, Nathan I.; Ghiran, Ionita C.

    2016-01-01

    Acute, inflammatory conditions associated with dysregulated complement activation are characterized by significant increases in blood concentration of reactive oxygen species (ROS) and ATP. The mechanisms by which these molecules arise are not fully understood. In this study, using luminometric- and fluorescence-based methods, we show that ligation of glycophorin A (GPA) on human red blood cells (RBCs) results in a 2.1-fold, NADPH-oxidase-dependent increase in intracellular ROS that, in turn, trigger multiple downstream cascades leading to caspase-3 activation, ATP release, and increased band 3 phosphorylation. Functionally, using 2D microchannels to assess membrane deformability, GPS-ligated RBCs travel 33% slower than control RBCs, and lipid mobility was hindered by 10% using fluorescence recovery after photobleaching (FRAP). These outcomes were preventable by pretreating RBCs with cell-permeable ROS scavenger glutathione monoethyl ester (GSH-ME). Our results obtained in vitro using anti-GPA antibodies were validated using complement-altered RBCs isolated from control and septic patients. Our results suggest that during inflammatory conditions, circulating RBCs significantly contribute to capillary flow dysfunctions, and constitute an important but overlooked source of intravascular ROS and ATP, both critical mediators responsible for endothelial cell activation, microcirculation impairment, platelet activation, as well as long-term dysregulated adaptive and innate immune responses. PMID:26784696

  11. Impact on red blood cell immunity patterns in postoperative phase following total hip arthroplasty

    PubMed Central

    Yu, Defu; Fu, Changma; Yu, Runze

    2014-01-01

    Objective In this study, we aimed to measure changes in red blood cell (RBC) immunity and cytokine levels after performing total hip replacement surgery. Material and methods Twenty patients receiving total hip arthroplasty were investigated by measuring presurgical and postoperative RBC natural tumor erythrocyte rosette rate (NTERR), RBC C3b receptor rosette rate (RC3bRR), RBC membrane CD35, CD58 and CD59 expression and cytokine levels [including tumor necrosis factor α (TNF-α), interleukin 2 (IL-2), interferon γ (IFN-γ), interleukin 10 (IL-10) and prostaglandin E2 (PGE2)]. Blood samples were collected on the day before surgery and on the first day after hip arthroplasty. Results Postoperative NTERR and RC3bRR were significantly lower than presurgical levels (p < 0.05). The RBC membrane CD35, CD58 and CD59 expressions were significantly decreased in the postoperative phase compared to pre-operative levels. Importantly, RBC promoting lymphocyte proliferation rates were significantly reduced after surgery. In addition, postoperative TNF-α, IL-2 and IFN-γ levels in RBC and lymphocyte culture fluid were lower than those pre-operation, whereas IL-10 and PGE2 were significantly increased compared to presurgical levels (p < 0.05). Conclusions The modification of RBC immune function may be involved in the occurrence and development of the infection following hip arthroplasty, and this suggests a novel strategy to prevent such infection. PMID:26155151

  12. 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.

  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. PMID:26822224

  14. 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. PMID:26926169

  15. Pathogen inactivation of whole blood and red cell components: an overview of concept, design, developments, criteria of acceptability and storage lesion.

    PubMed

    Seghatchian, Jerard; Putter, Jeffrey S

    2013-10-01

    Multilayer preventative strategies have been instituted to enhance transfusion safety for patients in need of critical blood components. Presently blood safety is at its highest levels, with the implementation of precautionary/preventative measures against vCJD, bacterial and viral contamination of the blood supply. The implementation of these strategies together with advances in automation and computerization led to significant improvements in standardisation for transfusion practices. These include validation, verification, adherence to GLP and GMP and other regulatory requirements. In most European countries, universal prestorage leukodepletion is routine practice. In France proactive pathogen inactivation treatments [PITs] have been implemented emphasizing patient safety. This at least conceptually reduces the risk of transfusing viable WBCs, emerging bacteria and viruses, all with potential transfusion complications. In the UK, prion removal filters for red cell products are used selectively for special groups of patients. Some research establishments are exploring the potential impact of pathogen inactivation of whole blood or red cell components, using the new generation of S-303 PIT and the prion removal filters in combination. It needs to be determined whether such a combined strategy, applied synergistically, enhances red cell transfusion safety without compromising the overall criteria of acceptability. It is necessary to critically examine the impact of a new generation of PIT technologies, which may exacerbate the red cell storage lesion and cause the development of undesirable antibodies in the recipient. The development of innovative laboratory tools is vital to study impacts of these measures on the quality of stored blood and their clinical outcome. The ultimate aim of red cell transfusion is to provide oxygen enriched red blood cells to the microcirculations and tissues. Definitive studies are needed to establish the potential unforeseen negative

  16. [Secondary prevention of stroke through arterial blood pressure reduction].

    PubMed

    Mancia, G; Grassi, G

    1997-07-01

    Large scale observational studies have conclusively demonstrated that systolic and diastolic blood pressure values are linearly related to the incidence of cerebrovascular diseases and that high blood pressure is an important risk factor for both primary and secondary development of stroke. Interventional studies have shown that blood pressure lowering by antihypertensive treatment reduces the incidence of stroke in hypertensive patients without a history of previous stroke. Whether this is the case also for the secondary prevention of cerebral ischemic attacks has not been unequivocally shown, however. The PROGRESS ("Perindopril Protection Against Recurrent Stroke Study") study has been designed and is under way to collect information on this important issue of the antihypertensive treatment, its purpose being to evaluate the blood pressure lowering effects with an ACE-inhibitor on recurrent stroke in an overall population of 6000 patients with a positive history of previous cerebral ischemic attacks or stroke. PMID:9340173

  17. 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

  18. Red blood cell sodium heteroexchange in familial primary hypertrophic cardiomyopathy.

    PubMed

    Semplicini, A; Mozzato, M G; Bongiovi, S; Marzola, M; Macor, F; Ceolotto, G; Serena, L; Pessina, A C

    1994-03-01

    The hallmark of primary hypertrophic cardiomyopathy is an inappropriate myocardial hypertrophy, linked to myofibril disarray of the left ventricle. Its variable clinical expression may be due to genetic heterogeneity and variable penetrance. Since we have recently shown that abnormalities of cation transport in the erythrocytes are associated with cardiac hypertrophy in essential hypertensives and insulin-dependent diabetics, we have investigated the relationship between cardiac anatomy and function and red cell Li+/Na+ and Na+/H+ exchange in 33 relatives of a patient who died of cardiac failure and was found to have a primary hypertrophic cardiomyopathy at autopsy. According to echocardiographic examination, 11 members of the family also had a hypertrophic cardiomyopathy, with a family distribution compatible with autosomal dominant genetic transmission and variable penetrance. Red cell Li+/Na+ and Na+/H+ exchange were not significantly different in the affected members as compared to the unaffected, but in the former, after correction for potentially confounding variables, interventricular septum thickness was positively correlated to Na+/H+ exchange and diastolic function (Area E/Area A and Vmax E/Vmax A) negatively correlated to Li+/Na+ exchange. Since a generalized overactivity of the cell membrane Na+/H+ exchange, reflected by increased Na+/H+ and Li+/Na+ exchanges in the red cells, could favour cellular growth and diastolic dysfunction, our data suggest that abnormalities of cell membrane cation transport could play a role in the phenotypic expression of hypertrophic cardiomyopathy. PMID:8013504

  19. A micro-scale simulation of red blood cell passage through symmetric and asymmetric bifurcated vessels.

    PubMed

    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

  20. 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

  1. 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.

  2. 99mTc-red blood cells SPECT and planar scintigraphy in the diagnosis of hepatic hemangiomas.

    PubMed

    Artiko, M V; Sobić-Saranović, P D; Perisić-Savić, S M; Stojković, V M; Radoman, B I; Knezević, S J; Petrović, S N; Obradović, B V; Milović, V

    2008-01-01

    The aim of the study is the assessment of the value of SPECT (single photon emission computerized tomography) using 99mTc-labeled red blood cells in the detection of liver hemangioma, in comparison to planar imaging. With planar red blood cell scintigraphy, sensitivity of the method was 76%, specificity 98%, positive predictive value 98% and negative predictive value 79%. With SPECT, sensitivity of the method was 95%, specificity 98%, positive predictive value 98% and negative predictive value 94%. The smallest lesion detected by planar red blood cell scintigraphy was 1.2 cm, and with SPECT red blood cell scintigraphy 0.8 cm. The use of 99mTc-labeled red blood cells SPECT improved the sensitivity much more in smaller lesions (0.8 to 2 cm), than in bigger ones (2-5 cm). SPECT with radiolabeled red blood cells significantlyy improves the results of scintigraphic findings, especially in the small lesions. PMID:19245136

  3. The exported Plasmodium berghei protein IBIS1 delineates membranous structures in infected red blood cells

    PubMed Central

    Ingmundson, Alyssa; Nahar, Carolin; Brinkmann, Volker; Lehmann, Maik J; Matuschewski, Kai

    2012-01-01

    Summary The importance of pathogen-induced host cell remodelling has been well established for red blood cell infection by the human malaria parasite Plasmodium falciparum. Exported parasite-encoded proteins, which often possess a signature motif, termed Plasmodium export element (PEXEL) or host-targeting (HT) signal, are critical for the extensive red blood cell modifications. To what extent remodelling of erythrocyte membranes also occurs in non-primate hosts and whether it is in fact a hallmark of all mammalian Plasmodium parasites remains elusive. Here we characterize a novel Plasmodium berghei PEXEL/HT-containing protein, which we term IBIS1. Temporal expression and spatial localization determined by fluorescent tagging revealed the presence of IBIS1 at the parasite/host interface during both liver and blood stages of infection. Targeted deletion of the IBIS1 protein revealed a mild impairment of intra-erythrocytic growth indicating a role for these structures in the rapid expansion of the parasite population in the blood in vivo. In red blood cells, the protein localizes to dynamic, punctate structures external to the parasite. Biochemical and microscopic data revealed that these intra-erythrocytic P. berghei-induced structures (IBIS) are membranous indicating that P. berghei, like P. falciparum, creates an intracellular membranous network in infected red blood cells. PMID:22329949

  4. 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.

  5. Osmotic tolerance limits of red blood cells from umbilical cord blood.

    PubMed

    Zhurova, Mariia; Lusianti, Ratih E; Higgins, Adam Z; Acker, Jason P

    2014-08-01

    Effective methods for long-term preservation of cord red blood cells (RBCs) are needed to ensure a readily available supply of RBCs to treat fetal and neonatal anemia. Cryopreservation is a potential long-term storage strategy for maintaining the quality of cord RBCs for the use in intrauterine and neonatal transfusion. However, during cryopreservation, cells are subjected to damaging osmotic stresses during cryoprotectant addition and removal and freezing and thawing that require knowledge of osmotic tolerance limits in order to optimize the preservation process. The objective of this study was to characterize the osmotic tolerance limits of cord RBCs in conditions relevant to cryopreservation, and compare the results to the osmotic tolerance limits of adult RBCs. Osmotic tolerance limits were determined by exposing RBCs to solutions of different concentrations to induce a range of osmotic volume changes. Three treatment groups of adult and cord RBCs were tested: (1) isotonic saline, (2) 40% w/v glycerol, and (3) frozen-thawed RBCs in 40% w/v glycerol. We show that cord RBCs are more sensitive to shrinkage and swelling than adult RBCs, indicating that osmotic tolerance limits should be considered when adding and removing cryoprotectants. In addition, freezing and thawing resulted in both cord and adult RBCs becoming more sensitive to post-thaw swelling requiring that glycerol removal procedures for both cell types ensure that cell volume excursions are maintained below 1.7 times the isotonic osmotically active volume to attain good post-wash cell recovery. Our results will help inform the development of optimized cryopreservation protocol for cord RBCs. PMID:24836371

  6. Detecting Newcastle disease virus in combination of RT-PCR with red blood cell absorption.

    PubMed

    Yi, Jianzhong; Liu, Chengqian

    2011-01-01

    Reverse transcription-polymerase chain reaction (RT-PCR) has limited sensitivity when treating complicated samples, such as feces, waste-water in farms, and nucleic acids, protein rich tissue samples, all the factors may interfere with the sensitivity of PCR test or generate false results. In this study, we developed a sensitive RT-PCR, combination of red blood cell adsorption, for detecting Newcastle disease virus (NDV). One pair of primers which was highly homologous to three NDV pathotypes was designed according to the consensus nucleocapsid protein (NP) gene sequence. To eliminate the interfere of microbes and toxic substances, we concentrated and purified NDV from varied samples utilizing the ability of NDV binding red blood cells (RBCs). The RT-PCR coupled with red blood cell adsorption was much more sensitive in comparison with regular RT-PCR. The approach could also be used to detect other viruses with the property of hemagglutination, such as influenza viruses. PMID:21535888

  7. Novel insights into red blood cell physiology using parasites as tools.

    PubMed

    Baumeister, Stefan; Gangopadhyay, Preetish; Repnik, Urska; Lingelbach, Klaus

    2015-01-01

    The mammalian red blood cell is a terminally differentiated cell that lacks a genetic programme and that has only a very limited metabolic capacity. Nonetheless, it serves as habitat for two parasites belonging to the monophyletic group of Apicomplexa, namely Plasmodium and Babesia. Studies of the parasitized red blood cell have revealed several properties that are unknown in the non-infected cell and that are difficult to conceptualize based on our view of red blood cell function. Here we review the current knowledge on host cell invasion and nutrient acquisition by these parasites. We attempt to dissect the factors that are directly contributed by the parasites from those that exist but have remained undetected in the non-infected cell. PMID:26105829

  8. 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.

  9. Attachment of antibody to biotinylated red blood cells: immuno-red blood cells display high affinity to immobilized antigen and normal biodistribution in rats.

    PubMed

    Muzykantov, V R; Murciano, J C

    1996-08-01

    Streptavidin-mediated attachment of biotinylated antibodies (b-Ab) to biotinylated red blood cells (b-RBC) is useful for preparation of immuno-red blood cells, a prospective vehicle for drug targeting. However, streptavidin (SA) induces lysis of extensively biotinylated RBC by complement due to cross-linking and inactivation of RBC complement regulators. To reduce cross-linking of RBC membrane proteins, we utilized mild biotinylation of RBC with 20 microM biotin ester (b20-RBC). SA effectively binds to rat b20-RBC (10(5) SA molecules/cell) and provides for following attachment of 5 x 10(4) molecules of b-IgG/SA per b20-RBC. By in vitro assay, b-Ab/SA/b20-RBC were stable in fresh rat serum. Serum-stable immuno-red blood cells (b-Ab/SA/b20-RBC) specifically bound to antigen-coated surfaces, but not to BSA-coated surfaces. Biodistribution of 51Cr-labelled b-Ab/SA/b20-RBC in rats was similar to that of control RBC, with no indication of lysis in vivo. These results suggest b-Ab/SA/b20-RBC may be explored as a vehicle for drug targeting. PMID:8756393

  10. Biochemical Storage Lesions Occurring in Nonirradiated and Irradiated Red Blood Cells: A Brief Review

    PubMed Central

    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. PMID:25710038

  11. 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

  12. A microfluidics approach for the isolation of nucleated red blood cells (NRBCs) from the peripheral blood of pregnant women

    PubMed Central

    Huang, R.; Barber, T. A.; Schmidt, M. A.; Tompkins, R. G.; Toner, M.; Bianchi, D. W.; Kapur, R.; Flejter, W. L.

    2015-01-01

    Objective Nucleated red blood cells (NRBCs) have been identified in maternal circulation and potentially provide a resource for the monitoring and diagnosis of maternal, fetal, and neonatal health and disease. Past strategies used to isolate and enrich for NRBCs are limited to complex approaches that result in low recovery and less than optimal cell purity. Here we report the development of a high-throughput and highly efficient microfluidic device for isolating rare NRBCs from maternal blood. Material and Methods NRBCs were isolated from the peripheral blood of 58 pregnant women using a microfluidic process that consists of a microfluidic chip for size-based cell separation and a magnetic device for hemoglobin-based cell isolation. Results The microfluidic–magnetic combination removes nontarget red blood cells and white blood cells at a very high efficiency (∼99.99%). The device successfully identified NRBCs from the peripheral blood of 58/58 pretermination samples with a mean of 37.44 NRBC/mL (range 0.37–274.36 NRBC/mL). These results were compared with those from previous studies. Conclusion The microfluidic device results in an approximate 10- to 20-fold enrichment of NRBCs over methods described previously. The reliability of isolation and the purity of the NRBC product have the potential to enable the subsequent application of molecular diagnostic assays. PMID:18821715

  13. Effect of exercise on erythrocyte count and blood activity concentration after technetium-99m in vivo red blood cell labeling

    SciTech Connect

    Konstom, M.A.; Tu'meh, S.; Wynne, J.; Beck, J.R.; Kozlowski, J.; Holman, B.L.

    1982-09-01

    The effects of exercise on blood radiotracer concentration after technetium-99m in vivo red blood cell labeling was studied. After red blood cell labeling, 13 subjects underwent maximal supine bicycle exercise. Radioactivity, analyzed with a well counter, was measured in heparinized venous blood samples drawn at rest and during peak exercise. Changes in activity were compared with changes in erythrocyte count. Activity and erythrocyte counts increased in erythrocyte count (r=0.78), but did not correlate with either duration of exercise or maximal heart rate. Twenty minutes after termination of exercise, activity and erythrocyte count had decreased from peak exercise values but remained higher than preexercise values. In nine nonexercised control subjects, samples drawn 20 minutes apart showed no change in activity or in erythrocyte count. It was concluded that exercise increases blood activity, primarily because of an increase in erythrocyte count. During radionuclide ventriculography, blood activity must be measured before and after any intervention, particularly exercise, before a change in left ventricular activity can be attributed to a change in left ventricular volume.

  14. 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. PMID:19168336

  15. 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.

  16. 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)

  17. From stem cell to red blood cells in vitro: "the 12 labors of Hercules".

    PubMed

    Douay, Luc

    2010-06-01

    This article describes the research in progress that will permit the large-scale production of human red blood cells from hematopoietic stem cells. It also discusses the current state of this research, suggests the obstacles to be overcome to pass from the laboratory model to clinical practice, and analyzes the possible indications in the medium and long term. The potential interest of pluripotent stem cells as an unlimited source of red blood cells is considered. If it succeeds, this new approach could mark a considerable advance in the field of transfusion. PMID:20513558

  18. Force Balance and Membrane Shedding at the Red-Blood-Cell Surface

    NASA Astrophysics Data System (ADS)

    Sens, Pierre; Gov, Nir

    2007-01-01

    During the aging of the red-blood cell, or under conditions of extreme echinocytosis, membrane is shed from the cell plasma membrane in the form of nanovesicles. We propose that this process is the result of the self-adaptation of the membrane surface area to the elastic stress imposed by the spectrin cytoskeleton, via the local buckling of membrane under increasing cytoskeleton stiffness. This model introduces the concept of force balance as a regulatory process at the cell membrane and quantitatively reproduces the rate of area loss in aging red-blood cells.

  19. Reflectance changes in clotting native blood: evidence of a red-cell process.

    PubMed

    Greco, Frank A

    2007-01-01

    When broadband light illuminates clotting native blood, the reflectance at each wavelength traces a time course with four discernible regions. Clot formation occurs just before the second phase. Two wavelengths, 471 and 771 nm, were selected for more detailed study of the first two phases. Analysis of each time course in native blood demonstrates that both signals track a single process during the first phase, but distinct processes during the second. Experiments on citrated blood identified which blood components contribute to reflectance changes. Comparison of liquid and clotting blood reveals a single process during the first phase, entailing that rouleaux formation determines the time course at both wavelengths. Control experiments eliminate clot propagation and shape change of red cells or platelets as possible factors in the second phase. Exogenous ADP added to EDTA blood evokes the second-phase response at 471 but not 771 nm, a novel phenomenon that requires the presence of red cells. The descriptive name 'ADP-end-response' is suggested for this red cell process until it is further characterized. We propose that the ADP-end-response determines the 471-nm signal during the second phase of clotting native blood and depends upon platelets in the absence of exogenous ADP. The 771-nm signal reports fibrin cross-linking during the second phase. An earlier pilot study demonstrated that rofecoxib effects the 471-nm signal ex vivo, which indicates that reflectance spectroscopy may be useful in the assessment of drug effects on platelet-erythrocyte interactions. PMID:18332611

  20. 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.

  1. Blood Thixotropy in Patients with Sickle Cell Anaemia: Role of Haematocrit and Red Blood Cell Rheological Properties

    PubMed Central

    Vent-Schmidt, Jens; Waltz, Xavier; Romana, Marc; Hardy-Dessources, Marie-Dominique; Lemonne, Nathalie; Billaud, Marie; Etienne-Julan, Maryse; Connes, Philippe

    2014-01-01

    We compared the blood thixotropic/shear-thinning properties and the red blood cells’ (RBC) rheological properties between a group of patients with sickle cell anaemia (SS) and healthy individuals (AA). Blood thixotropy was determined by measuring blood viscosity with a capillary viscometer using a “loop” protocol: the shear rate started at 1 s−1 and increased progressively to 922 s−1 and then re-decreased to the initial shear rate. Measurements were performed at native haematocrit for the two groups and at 25% and 40% haematocrit for the AA and SS individuals, respectively. RBC deformability was determined by ektacytometry and RBC aggregation properties by laser backscatter versus time. AA at native haematocrit had higher blood thixotropic index than SS at native haematocrit and AA at 25% haematocrit. At 40% haematocrit, SS had higher blood thixotropic index than AA. While RBC deformability and aggregation were lower in SS than in AA, the strength of RBC aggregates was higher in the former population. Our results showed that 1) anaemia is the main modulator of blood thixtropy and 2) the low RBC deformability and high RBC aggregates strength cause higher blood thixotropy in SS patients than in AA individuals at 40% haematocrit, which could impact blood flow in certain vascular compartments. PMID:25502228

  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. PMID:22390095

  3. Red blood cell orientation in orbit C = 0.

    PubMed Central

    Bitbol, M

    1986-01-01

    Two modes of behavior of single human red cells in a shear field have been described. It is known that in low viscosity media and at shear rates less than 20 s-1, the cells rotate with a periodically varying angular velocity, in accord with the theory of Jeffery (1922) for oblate spheroids. In media of viscosity greater than approximately 5 mPa s and sufficiently high shear rates, the cells align themselves at a constant angle to the direction of flow with the membrane undergoing tank-tread motion. Also, in low viscosity media, as the shear rate is increased, more and more cells lie in the plane of shear, undergoing spin with their axes of symmetry aligned with the vorticity axis of the shear field in an orbit "C = 0" (Goldsmith and Marlow, 1972). We have explored this latter phenomenon using two experimental methods. First, the erythrocytes were observed in the rheoscope and their diameters measured. Forward light scattering patterns were correlated with the red cell orientation mode. Light flux variations after flow onset or stop were measured, and the characteristic times of erythrocyte orientation and disorientation were assessed. The characteristic time of erythrocyte orientation in Orbit C = 0 is proportional to the inverse of the shear rate. The corresponding coefficient of proportionality depends on the suspending medium viscosity eta o. The disorientation time tau D, after flow has been stopped, is such that the ratio tau D/eta o is independent of the initial applied shear stress. However, tau D is much shorter than one would expect if pure Brownian motion were involved. The proportion of erythrocytes in orbit C = 0 was also measured. It was found that this proportion is a function of both the shear rate and eta o. At low values of eta o, the proportion increases with increasing shear rate and then reaches a plateau. For higher values of eta o (5 to 10 mPa s), the proportion of RBC in orbit C = 0 is a decreasing function of the shear stress. A critical

  4. Is red meat required for the prevention of iron deficiency among children and adolescents?

    PubMed

    Savva, Savvas C; Kafatos, Anthony

    2014-01-01

    Iron deficiency remains the most common nutritional deficiency worldwide despite the fact that global prevention is a high priority. Recent guidelines suggest intake of red meat both in infants and toddlers to prevent iron deficiency. However frequent consumption of red and processed meat may be associated with an increased risk for cancer, cardiovascular disease and diabetes. Evidence also suggests that even in vegetarian diets or diets with little consumption of white or red meat, iron status may not be adversely affected. The Eastern Orthodox Christian Church dietary recommendations which is a type of periodic vegetarian diet, has proved beneficial for the prevention of iron deficiency and avoidance of excess iron intake. This paper aims to provide examples of meals for children and adolescents that may be sufficient to meet age specific iron requirements without consumption of red meat beyond the recommended consumption which is once or twice per month. PMID:25088337

  5. 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.

  6. 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. PMID:26415744

  7. Oscillation dynamics of embolic microspheres in flows with red blood cell suspensions

    NASA Astrophysics Data System (ADS)

    Das, Tamal; Carugo, Dario; Zhang, Xunli; Chakraborty, Suman

    2012-12-01

    Dynamic nature of particle motion in blood flow is an important determinant of embolization based cancer therapy. Yet, the manner in which the presence of high volume fraction of red blood cells influences the particle dynamics remains unknown. Here, by investigating the motions of embolic microspheres in pressure-driven flows of red blood cell suspensions through capillaries, we illustrate unique oscillatory trends in particle trajectories, which are not observable in Newtonian fluid flows. Our investigation reveals that such oscillatory behavior essentially manifests when three simultaneous conditions, namely, the Reynolds number beyond a threshold limit, degree of confinement beyond a critical limit, and high hematocrit level, are fulfilled simultaneously. Given that these conditions are extremely relevant to fluid dynamics of blood or polymer flow, the observations reported here bear significant implications on embolization based cancer treatment as well as for complex multiphase fluidics involving particles.

  8. Red blood cells are a sink for interleukin 8, a leukocyte chemotaxin.

    PubMed

    Darbonne, W C; Rice, G C; Mohler, M A; Apple, T; Hébert, C A; Valente, A J; Baker, J B

    1991-10-01

    IL-8 (also known as neutrophil-activating peptide 1) is recognized as a potent effector of neutrophil functions. Several different cell types that contact blood, namely T lymphocytes, monocytes, and endothelial cells, secrete this polypeptide following stimulation by cytokines, or lipopolysaccharide. Here we show that when IL-8 is added to blood it rapidly partitions from the plasma fluid to the blood cells and that erythrocytes account for the vast majority of this binding. Analysis of 125I-IL-8 binding [( ala-IL-8]77 form) to human red cells indicates a single, 5 nM Kd affinity class of binding sites, present at approximately 2,000 per red cell representing approximately 15 nmol of red cell IL-8 binding sites per liter of blood. These sites are protease sensitive. Their binding of IL-8 is rapidly reversible and does not result in receptor internalization, although bound IL-8 is resistant to extraction by pH 3 buffer at 5 degrees C. 125I-IL-8 binding to red cells was not inhibited by epidermal growth factor or interleukin 1, but was inhibited by monocyte chemotactic peptide-1, which is not a neutrophil chemotaxin, but is a member of the same family of polypeptides as IL-8. FACS analysis of IL-8-mediated mobilization of Ca2+ in neutrophils indicates that the IL-8 bound to red cells is incapable of stimulating neutrophils. Thus, red cell absorption of IL-8 may function to limit stimulation of leukocytes by IL-8 released into blood. PMID:1918386

  9. Where does blood go? Prospective observational study of red cell transfusion in north England

    PubMed Central

    Wells, A W; Mounter, P J; Chapman, C E; Stainsby, D; Wallis, J P

    2002-01-01

    Objective To collect population based information on transfusion of red blood cells. Design Prospective observational study over 28 days. Setting Hospital blood banks in the north of England (population 2.9 million). Main outcome measures Indications for transfusion, number of units given, and the age and sex of transfusion recipients. Participants All patients who received a red cell transfusion during the study period. Data completed by hospital blood bank staff. Results The destination of 9848 units was recorded (97% of expected blood use). In total 9774 units were transfused: 5047 (51.6%) units were given to medical patients, 3982 (40.7%) to surgical patients, and 612 (6.3%) to obstetric and gynaecology patients. Nearly half (49.3%) of all blood is given to female recipients, and the mean age of recipients of individual units was 62.7 years. The most common surgical indications for transfusion were total hip replacement (4.6% of all blood transfused) and coronary artery bypass grafting (4.1%). Haematological disorders accounted for 15.5% of use. Overall use was 4274 units per 100 000 population per year. Conclusion In the north east of England more than half of red cell units are transfused for medical indications. Demand for red cell transfusion increases with age. With anticipated changes in the age structure of the population the demand for blood will increase by 4.9% by 2008. What is already known on this topicThere have been no systematic population based surveys on use of red cells in the United KingdomStudies in France and the United States have shown that more than half of transfused red cells go to surgical patientsWhat this study addsIn the north of England over half of red cells are given for medical indicationsRates of red cell transfusion rise steeply with advancing ageSmall increases in the number of elderly people will have large effects on demand PMID:12376439

  10. EVALUATION OF RED BLOOD CELL INDICES RELATED DISORDERS AMONG ELIGIBLE BLOOD DONORS AT THE UNIVERSITI PUTRA MALAYSIA (UPM).

    PubMed

    Riahi, Shahrzad; Mei, I Lai; Idris, Fariddh Binti; George, Elizabeth; Noor, Sabariah Md

    2015-09-01

    Pre-donation screening declarations and hemoglobin (Hb) testing are measures used to determine the quality of donated blood. The copper sulphate (CuSo4) method used to screen for blood abnormalities can give inaccurate results if strict quality control is not applied. Blood donors who are carriers of thalassemia and those with mild iron deficiency anemia (IDA) are usually asymptomatic and frequently missed at blood donation. The aim of this study was to evaluate the red blood cell (RBC) indices related disorders among blood donors who were deemed qualified to donate blood after screening with CuSo4 method. One hundred fifty-eight volunteer blood donors at the Universiti Putra Malaysia (UPM), who had passed the CuSo4 screening method, were recruited for this study. Their bloods specimens were examined with a complete blood count. Subjects with a low mean corpuscular hemoglobin (MCH) level were examined further by checking a serum ferritin level, Hb quantification, and molecular analysis to examine for common RBC disorders. Fourteen point six percent of subjects had a low Hb level, two (1.3%) had IDA and four (2.5%) had thalassemia or some other hemoglobinopathy. Using a MCH level < 27 pg as a cut-off point, 58 subjects (36.7%) had suspected IDA, thalassemia or some other hemoglobinopathy. Eight point nine percent of subjects with a normal Hb level had thalassemia, and 3.8% had IDA. Malaysia has a high prevalence of thalassemia and other hemoglobinopathies. Pre-donation accurate screening is crucial to protect the quality of blood transfusion products. Public education regarding RBC disorders especially among blood donors is important. PMID:26863862

  11. Bridging channel dendritic cells induce immunity to transfused red blood cells.

    PubMed

    Calabro, Samuele; Gallman, Antonia; Gowthaman, Uthaman; Liu, Dong; Chen, Pei; Liu, Jingchun; Krishnaswamy, Jayendra Kumar; Nascimento, Manuela Sales L; Xu, Lan; Patel, Seema R; Williams, Adam; Tormey, Christopher A; Hod, Eldad A; Spitalnik, Steven L; Zimring, James C; Hendrickson, Jeanne E; Stowell, Sean R; Eisenbarth, Stephanie C

    2016-05-30

    Red blood cell (RBC) transfusion is a life-saving therapeutic tool. However, a major complication in transfusion recipients is the generation of antibodies against non-ABO alloantigens on donor RBCs, potentially resulting in hemolysis and renal failure. Long-lived antibody responses typically require CD4(+) T cell help and, in murine transfusion models, alloimmunization requires a spleen. Yet, it is not known how RBC-derived antigens are presented to naive T cells in the spleen. We sought to answer whether splenic dendritic cells (DCs) were essential for T cell priming to RBC alloantigens. Transient deletion of conventional DCs at the time of transfusion or splenic DC preactivation before RBC transfusion abrogated T and B cell responses to allogeneic RBCs, even though transfused RBCs persisted in the circulation for weeks. Although all splenic DCs phagocytosed RBCs and activated RBC-specific CD4(+) T cells in vitro, only bridging channel 33D1(+) DCs were required for alloimmunization in vivo. In contrast, deletion of XCR1(+)CD8(+) DCs did not alter the immune response to RBCs. Our work suggests that blocking the function of one DC subset during a narrow window of time during RBC transfusion could potentially prevent the detrimental immune response that occurs in patients who require lifelong RBC transfusion support. PMID:27185856

  12. Optical Tweezers as a New Biomedical Tool to Measure Zeta Potential of Stored Red Blood Cells

    PubMed Central

    Silva, Carlos A. L.; Fernandes, Heloise P.; Filho, Milton M.; Lucena, Sheyla C.; Costa, Ana Maria D. N.; Cesar, Carlos L.; Barjas-Castro, Maria L.; Santos, Beate S.; Fontes, Adriana

    2012-01-01

    During storage, red blood cells (RBCs) for transfusion purposes suffer progressive deterioration. Sialylated glycoproteins of the RBC membrane are responsible for a negatively charged surface which creates a repulsive electrical zeta potential. These charges help prevent the interaction between RBCs and other cells, and especially among each RBCs. Reports in the literature have stated that RBCs sialylated glycoproteins can be sensitive to enzymes released by leukocyte degranulation. Thus, the aim of this study was, by using an optical tweezers as a biomedical tool, to measure the zeta potential in standard RBCs units and in leukocyte reduced RBC units (collected in CPD-SAGM) during storage. Optical tweezers is a sensitive tool that uses light for measuring cell biophysical properties which are important for clinical and research purposes. This is the first study to analyze RBCs membrane charges during storage. In addition, we herein also measured the elasticity of RBCs also collected in CPD-SAGM. In conclusion, the zeta potential decreased 42% and cells were 134% less deformable at the end of storage. The zeta potential from leukodepleted units had a similar profile when compared to units stored without leukoreduction, indicating that leukocyte lyses were not responsible for the zeta potential decay. Flow cytometry measurements of reactive oxygen species suggested that this decay is due to membrane oxidative damages. These results show that measurements of zeta potentials provide new insights about RBCs storage lesion for transfusion purposes. PMID:22363729

  13. Expression of CD55 on red blood cells of β-thalassemia patients.

    PubMed

    Obaid, Jamil M A S; Abo El-Nazar, Salma Y; Ghanem, Amal M; El-Hadidi, Abeer S; Mersal, Basma H M

    2014-01-01

    CD55 is a complement regulatory protein expressed by cells to protect them from bystander lysis by complement. It prevents the formation of C3/C5 convertase. In β-thalassemia (β-thal), the defective hemoglobin (Hb) production makes red blood cells (RBCs) lyse early and frequently. Loss of CD55 expression in those patients compromises the complement regulatory function, thereby accelerating RBC lysis. In this study, we aimed to evaluate the expression of CD55 on erythrocytes of β-thal patients. Flow cytometry analysis of CD55 was conducted on RBCs of 21 β-thalassemia major (β-TM) patients, 11 β-thalassemia intermedia (β-TI) patients and 10 healthy volunteers. The results showed a significant decrease in CD55 expression in β-TM (57.5 ± 16.7%), while there was a slight decrease in β-TI patients (81.8 ± 3.8%) in comparison with that of the normal controls (88.7 ± 0.8%). The diminished expression of CD55 was not accompanied by decrease in CD59 expression in β-thal patients (97.2 ± 2.3%). This could suggest a mechanism (could be genetic) responsible for low CD55 expression. It may be related to defective Hb genes in thalassemia, but it does not relate to cell membrane changes. PMID:25026028

  14. Mineralocorticoid receptor is involved in the aldosterone pathway in human red blood cells

    PubMed Central

    Bordin, Luciana; Saccardi, Carlo; Donà, Gabriella; Sabbadin, Chiara; Andrisani, Alessandra; Ambrosini, Guido; Plebani, Mario; Brunati, Anna Maria; Ragazzi, Eugenio; Gizzo, Salvatore; Armanini, Decio

    2016-01-01

    We have recently demonstrated that excessive aldosterone (Aldo) secretion in primary aldosteronism (PA) is associated with red blood cells (RBC) senescence. These alterations were prevented/inhibited by cortisol (Cort) or canrenone (Can) raising the hypothesis that Aldo effects in RBC may be mediated by mineralocorticoid receptor (MR), though to date MR has never been demonstrated in human RBC. The aim of this multicenter comparative study was to investigate whether Aldo effects were mediated by MR in these a-nucleated cells. We included 12 healthy controls (HC) and 22 patients with PA. MR presence and activation were evaluated in RBC cytosol by glycerol gradient sedimentation, Western blotting, immuno-precipitation and radioimmunoassay. We demonstrated that RBC contained cytosolic MR, aggregated with HSP90 and other proteins to form multiprotein complex. Aldo induced MR to release from the complex and to form MR dimers which were quickly proteolyzed. Cort induced MR release but not dimers formation while Can was not able to induce MR release. In addition, RBC cytosol from PA patients contained significantly higher amounts of both MR fragments (p<0.0001) and Aldo (p<0.0001) concentrations. In conclusion, in RBC a genomic-like Aldo pathway is proposed involving MR activation, dimerization and proteolysis, but lacking nuclear transcription. In addition, dimers proteolysis may ensure a sort of Aldo scavenging from circulation by entrapping Aldo in MR fragments. PMID:27158328

  15. Mineralocorticoid receptor is involved in the aldosterone pathway in human red blood cells.

    PubMed

    Bordin, Luciana; Saccardi, Carlo; Donà, Gabriella; Sabbadin, Chiara; Andrisani, Alessandra; Ambrosini, Guido; Plebani, Mario; Brunati, Anna Maria; Ragazzi, Eugenio; Gizzo, Salvatore; Armanini, Decio

    2016-01-01

    We have recently demonstrated that excessive aldosterone (Aldo) secretion in primary aldosteronism (PA) is associated with red blood cells (RBC) senescence. These alterations were prevented/inhibited by cortisol (Cort) or canrenone (Can) raising the hypothesis that Aldo effects in RBC may be mediated by mineralocorticoid receptor (MR), though to date MR has never been demonstrated in human RBC. The aim of this multicenter comparative study was to investigate whether Aldo effects were mediated by MR in these a-nucleated cells. We included 12 healthy controls (HC) and 22 patients with PA. MR presence and activation were evaluated in RBC cytosol by glycerol gradient sedimentation, Western blotting, immuno-precipitation and radioimmunoassay. We demonstrated that RBC contained cytosolic MR, aggregated with HSP90 and other proteins to form multiprotein complex. Aldo induced MR to release from the complex and to form MR dimers which were quickly proteolyzed. Cort induced MR release but not dimers formation while Can was not able to induce MR release. In addition, RBC cytosol from PA patients contained significantly higher amounts of both MR fragments (p<0.0001) and Aldo (p<0.0001) concentrations. In conclusion, in RBC a genomic-like Aldo pathway is proposed involving MR activation, dimerization and proteolysis, but lacking nuclear transcription. In addition, dimers proteolysis may ensure a sort of Aldo scavenging from circulation by entrapping Aldo in MR fragments. PMID:27158328

  16. Deformability based sorting of red blood cells improves diagnostic sensitivity for malaria caused by Plasmodium falciparum.

    PubMed

    Guo, Quan; Duffy, Simon P; Matthews, Kerryn; Deng, Xiaoyan; Santoso, Aline T; Islamzada, Emel; Ma, Hongshen

    2016-02-21

    The loss of red blood cell (RBC) deformability is part of the pathology of many diseases. In malaria caused by Plasmodium falciparum infection, metabolism of hemoglobin by the parasite results in progressive reduction in RBC deformability that is directly correlated with the growth and development of the parasite. The ability to sort RBCs based on deformability therefore provides a means to isolate pathological cells and to study biochemical events associated with disease progression. Existing methods have not been able to sort RBCs based on deformability or to effectively enrich for P. falciparum infected RBCs at clinically relevant concentrations. Here, we develop a method to sort RBCs based on deformability and demonstrate the ability to enrich the concentration of ring-stage P. falciparum infected RBCs (Pf-iRBCs) by >100× from clinically relevant parasitemia (<0.01%). Deformability based sorting of RBCs is accomplished using ratchet transport through asymmetrical constrictions using oscillatory flow. This mechanism provides dramatically improved selectivity over previous biophysical methods by preventing the accumulation of cells in the filter microstructure to ensure that consistent filtration forces are applied to each cell. We show that our approach dramatically improves the sensitivity of malaria diagnosis performed using both microscopy and rapid diagnostic test by converting samples with difficult-to-detect parasitemia (<0.01%) into samples with easily detectable parasitemia (>0.1%). PMID:26768227

  17. ["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. PMID:17152589

  18. Risk factors for hepatitis B carrier status among blood donors of the National Blood Center, Thai Red Cross Society.

    PubMed

    Nuchprayoon, T; Chumnijarakij, T

    1992-06-01

    A study of risk factors for hepatitis B carriers among voluntary blood donors of the National Blood Center, Thai Red Cross Society was carried out in a case-control study design during January 1989 to June 1990. Cases were 876 blood donors whose blood identified HBsAg at time of recruitment and continued positive for more than 6 months. Controls were 1,750 blood donors whose blood was free from HBsAg who came for blood donation at the same period as the cases. The ratio of cases:controls = 1:2. Self-administered questionnaires were constructed and pretested before using both cases and controls. The study revealed that the risk factors for hepatitis B among voluntary blood donors were age of less than 30 years old; low socioeconomic status (family income of less than 8,000 Baht/month); single status, especially males; male occupations of students, monks, nongovernment workers compared with government officials; female occupations of laborers, students, nongovernment workers and government officials compared with housewives. Sharing of nail clippers, used blades and tooth brushes among family members are proved to be risk factors, especially among males. In addition, sharing of used blades in barber shops proved to be a risk among males while sharing of nail clippers in beauty salons, history of ear-piercing at department stores or history of caesarean section among females could not be shown to be risk factors.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1439976

  19. Sphero-echinocytosis of human red blood cells caused by snake, red-back spider, bee and blue-ringed octopus venoms and its inhibition by snake sera.

    PubMed

    Flachsenberger, W; Leigh, C M; Mirtschin, P J

    1995-06-01

    It was found that bee (Apis mellifera) venom, red-back spider (Latrodectus mactans) venom, blue-ringed octopus (Hapalochlaena maculosa) venom, ten different snake venoms, phospholipase A2 and four snake toxins caused sphero-echinocytosis of human red blood cells at 200 ng/ml. Most venoms and toxins lost the ability to deform human red blood cells when their components of less than mol. wt 10,000 were applied. In a number of cases the sphero-echinocytotic effect was also inhibited by blood sera of Notechis scutatus and Pseudonaja textilis. PMID:7676470

  20. The plasma protein fibrinogen stabilizes clusters of red blood cells in microcapillary flows

    PubMed Central

    Brust, M.; Aouane, O.; Thiébaud, M.; Flormann, D.; Verdier, C.; Kaestner, L.; Laschke, M. W.; Selmi, H.; Benyoussef, A.; Podgorski, T.; Coupier, G.; Misbah, C.; Wagner, C.

    2014-01-01

    The supply of oxygen and nutrients and the disposal of metabolic waste in the organs depend strongly on how blood, especially red blood cells, flow through the microvascular network. Macromolecular plasma proteins such as fibrinogen cause red blood cells to form large aggregates, called rouleaux, which are usually assumed to be disaggregated in the circulation due to the shear forces present in bulk flow. This leads to the assumption that rouleaux formation is only relevant in the venule network and in arterioles at low shear rates or stasis. Thanks to an excellent agreement between combined experimental and numerical approaches, we show that despite the large shear rates present in microcapillaries, the presence of either fibrinogen or the synthetic polymer dextran leads to an enhanced formation of robust clusters of red blood cells, even at haematocrits as low as 1%. Robust aggregates are shown to exist in microcapillaries even for fibrinogen concentrations within the healthy physiological range. These persistent aggregates should strongly affect cell distribution and blood perfusion in the microvasculature, with putative implications for blood disorders even within apparently asymptomatic subjects. PMID:24614613

  1. The plasma protein fibrinogen stabilizes clusters of red blood cells in microcapillary flows

    NASA Astrophysics Data System (ADS)

    Brust, M.; Aouane, O.; Thiébaud, M.; Flormann, D.; Verdier, C.; Kaestner, L.; Laschke, M. W.; Selmi, H.; Benyoussef, A.; Podgorski, T.; Coupier, G.; Misbah, C.; Wagner, C.

    2014-03-01

    The supply of oxygen and nutrients and the disposal of metabolic waste in the organs depend strongly on how blood, especially red blood cells, flow through the microvascular network. Macromolecular plasma proteins such as fibrinogen cause red blood cells to form large aggregates, called rouleaux, which are usually assumed to be disaggregated in the circulation due to the shear forces present in bulk flow. This leads to the assumption that rouleaux formation is only relevant in the venule network and in arterioles at low shear rates or stasis. Thanks to an excellent agreement between combined experimental and numerical approaches, we show that despite the large shear rates present in microcapillaries, the presence of either fibrinogen or the synthetic polymer dextran leads to an enhanced formation of robust clusters of red blood cells, even at haematocrits as low as 1%. Robust aggregates are shown to exist in microcapillaries even for fibrinogen concentrations within the healthy physiological range. These persistent aggregates should strongly affect cell distribution and blood perfusion in the microvasculature, with putative implications for blood disorders even within apparently asymptomatic subjects.

  2. The plasma protein fibrinogen stabilizes clusters of red blood cells in microcapillary flows.

    PubMed

    Brust, M; Aouane, O; Thiébaud, M; Flormann, D; Verdier, C; Kaestner, L; Laschke, M W; Selmi, H; Benyoussef, A; Podgorski, T; Coupier, G; Misbah, C; Wagner, C

    2014-01-01

    The supply of oxygen and nutrients and the disposal of metabolic waste in the organs depend strongly on how blood, especially red blood cells, flow through the microvascular network. Macromolecular plasma proteins such as fibrinogen cause red blood cells to form large aggregates, called rouleaux, which are usually assumed to be disaggregated in the circulation due to the shear forces present in bulk flow. This leads to the assumption that rouleaux formation is only relevant in the venule network and in arterioles at low shear rates or stasis. Thanks to an excellent agreement between combined experimental and numerical approaches, we show that despite the large shear rates present in microcapillaries, the presence of either fibrinogen or the synthetic polymer dextran leads to an enhanced formation of robust clusters of red blood cells, even at haematocrits as low as 1%. Robust aggregates are shown to exist in microcapillaries even for fibrinogen concentrations within the healthy physiological range. These persistent aggregates should strongly affect cell distribution and blood perfusion in the microvasculature, with putative implications for blood disorders even within apparently asymptomatic subjects. PMID:24614613

  3. Stem Cell Physics. Laser Manipulation of Blood Types: Laser-Stripping-Away of Red Blood Cell Surface Antigens

    NASA Astrophysics Data System (ADS)

    Stefan, V. Alexander

    2014-03-01

    A novel mechanism of importance for the transfusion medicine[2] is proposed. The interaction of ultrashort wavelength multilaser beams with the flowing blood thin films can lead to a conversion of blood types A, B, and AB into O type.[3] The stripping away of antigens is done by the scanning-multiple-lasers of a high repetition rate in the blue-purple frequency domain. The guiding-lasers are in the red-green frequency domain. The laser force, (parametric interaction with the antigen eigen-oscillation),[4] upon the antigen protein molecule must exceed its weight. Supported by Nikola Tesla Labs, La Jolla, CA.

  4. Temperatures associated with thermally induced red blood cell changes in tissues irradiated in vivo

    NASA Astrophysics Data System (ADS)

    Thomsen, Sharon L.; Schwartz, Jon A.; Joseph, Rachel; Pearce, John A.; Rae, Brian; McMurray, Tom J.

    1994-07-01

    Photothermal coagulation and ablation lesions were produced in exposed livers of anesthetized rats with a cw Nd:YAG laser ((lambda) equals1064 nm; beam power 3.2 to 10 W; exposure times 3 to 10 s, and spot diameter, 0.7 to 1.9 mm). The surface temperatures produced by the irradiations were derived from IR camera images calibrated with temperature controlled black bodies present in the scene. Targetoid lesions with central white and outer red zones marked areas of surface and deep coagulation grossly. The animals were sacrificed 30 minutes after irradiation. The lesions and surrounding normal liver were collected for light microscopy. Microscopically, characteristic, thermally-induced red blood cell alterations were found in the white and red zones and at the boundaries separating them. The boundaries of the concentric surface zones were measured grossly from the lesion centers and compared to the thermal images to determine the temperatures associated with the red blood cell changes. The temperatures for the surface and deep morphologic isotherms defined by the white/red and red/normal boundaries of rat liver irradiated in vivo are 68+/- 5.0 degree(s)C and 55+/- 2.7 degree(s)C.

  5. Investigating the fluid mechanics behind red blood cell-induced lateral platelet motion

    NASA Astrophysics Data System (ADS)

    Crowl Erickson, Lindsay; Fogelson, Aaron

    2009-11-01

    Platelets play an essential role in blood clotting; they adhere to damaged tissue and release chemicals that activate other platelets. Yet in order to adhere, platelets must first come into contact with the injured vessel wall. Under arterial flow conditions, platelets have an enhanced concentration near blood vessel walls. This non-uniform cell distribution depends on the fluid dynamics of blood as a heterogeneous medium. We use a parallelized lattice Boltzmann-immersed boundary method to solve the flow dynamics of red cells and platelets in a periodic 2D vessel with no-slip boundary conditions. Red cells are treated as biconcave immersed boundary objects with isotropic Skalak membrane tension and an internal viscosity five times that of the surrounding plasma. Using this method we analyze the influence of shear rate, hematocrit, and red cell membrane properties on lateral platelet motion. We find that the effective diffusion of platelets is significantly lower near the vessel wall compared to the center of the vessel. Insight gained from this work could lead to significant improvements to current models for platelet adhesion where the presence of red blood cells is neglected due to computational intensity.

  6. Hemoglobin Aggregation in Single Red Blood Cells of Sickle Cell Anemia

    NASA Astrophysics Data System (ADS)

    Nishio, Izumi; Tanaka, Toyoichi; Sun, Shao-Tang; Imanishi, Yuri; Tsuyoshi Ohnishi, S.

    1983-06-01

    A laser light scattering technique was used to observe the extent of hemoglobin aggregation in solitary red blood cells of sickle cell anemia. Hemoglobin aggregation was confirmed in deoxygenated cells. The light scattering technique can also be applied to cytoplasmic studies of any biological cell.

  7. Red blood cell fatty acid composition and the metabolic syndrome: NHLBI GOLDN study

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Different fatty acids may vary in their effect on the metabolic syndrome (MetS). We tested whether fatty acid classes measured in red blood cells (RBC) are associated with the MetS or its components. Included were men (n=497, 49+/-16 y) and women (n=539, 48+/-16 y) from 187 families in the Genetics ...

  8. Metabolic profiling of hematopoietic stem and progenitor cells during proliferation and differentiation into red blood cells.

    PubMed

    Daud, Hasbullah; Browne, Susan; Al-Majmaie, Rasoul; Murphy, William; Al-Rubeai, Mohamed

    2016-01-25

    An understanding of the metabolic profile of cell proliferation and differentiation should support the optimization of culture conditions for hematopoietic stem and progenitor cell (HSPC) proliferation, differentiation, and maturation into red blood cells. We have evaluated the key metabolic parameters during each phase of HSPC culture for red blood cell production in serum-supplemented (SS) and serum-free (SF) conditions. A simultaneous decrease in growth rate, total protein content, cell size, and the percentage of cells in the S/G2 phase of cell cycle, as well as an increase in the percentage of cells with a CD71(-)/GpA(+) surface marker profile, indicates HSPC differentiation into red blood cells. Compared with proliferating HSPCs, differentiating HSPCs showed significantly lower glucose and glutamine consumption rates, lactate and ammonia production rates, and amino acid consumption and production rates in both SS and SF conditions. Furthermore, extracellular acidification was associated with late proliferation phase, suggesting a reduced cellular metabolic rate during the transition from proliferation to differentiation. Under both SS and SF conditions, cells demonstrated a high metabolic rate with a mixed metabolism of both glycolysis and oxidative phosphorylation (OXPHOS) in early and late proliferation, an increased dependence on OXPHOS activity during differentiation, and a shift to glycolytic metabolism only during maturation phase. These changes indicate that cell metabolism may have an important impact on the ability of HSPCs to proliferate and differentiate into red blood cells. PMID:26013297

  9. Automatic tracking of red blood cells in micro channels using OpenCV

    NASA Astrophysics Data System (ADS)

    Rodrigues, Vânia; Rodrigues, Pedro J.; Pereira, Ana I.; Lima, Rui

    2013-10-01

    The present study aims to developan automatic method able to track red blood cells (RBCs) trajectories flowing through a microchannel using the Open Source Computer Vision (OpenCV). The developed method is based on optical flux calculation assisted by the maximization of the template-matching product. The experimental results show a good functional performance of this method.

  10. Isoelectric focusing of red blood cells in a density gradient stabilized column

    NASA Technical Reports Server (NTRS)

    Smolka, A. J. K.; Miller, T. Y.

    1980-01-01

    The effects of Ficoll and cell application pH on red blood cell electrophoretic mobility and focusing pH were investigated by focusing cells in a density gradient stabilized column. Sample loading, cell dispersion, column conductivity, resolution of separation, and the effect of Ampholines were examined.

  11. Prolonged cold storage of red blood cells by oxygen removal and additive usage

    DOEpatents

    Bitensky, M.W.; Yoshida, Tatsuro

    1998-08-04

    Prolonged cold storage of red blood cells by oxygen removal and additive usage. A cost-effective, 4 C storage procedure that preserves red cell quality and prolongs post-transfusion in vivo survival is described. The improved in vivo survival and the preservation of adenosine triphosphate levels, along with reduction in hemolysis and membrane vesicle production of red blood cells stored at 4 C for prolonged periods of time, is achieved by reducing the oxygen level therein at the time of storage; in particular, by flushing the cells with an inert gas, and storing them in an aqueous solution which includes adenine, dextrose, mannitol, citrate ion, and dihydrogen phosphate ion, but no sodium chloride, in an oxygen-permeable container which is located in an oxygen-free environment containing oxygen-scavenging materials. 8 figs.

  12. Prolonged cold storage of red blood cells by oxygen removal and additive usage

    DOEpatents

    Bitensky, Mark W.; Yoshida, Tatsuro

    1998-01-01

    Prolonged cold storage of red blood cells by oxygen removal and additive usage. A cost-effective, 4.degree. C. storage procedure that preserves red cell quality and prolongs post-transfusion in vivo survival is described. The improved in vivo survival and the preservation of adenosine triphosphate levels, along with reduction in hemolysis and membrane vesicle production of red blood cells stored at 4.degree. C. for prolonged periods of time, is achieved by reducing the oxygen level therein at the time of storage; in particular, by flushing the cells with an inert gas, and storing them in an aqueous solution which includes adenine, dextrose, mannitol, citrate ion, and dihydrogen phosphate ion, but no sodium chloride, in an oxygen-permeable container which is located in an oxygen-free environment containing oxygen-scavenging materials.

  13. A method for drying red blood cells for solid-phase immunoassay.

    PubMed

    Tamai, T; Mazda, T

    1999-12-01

    To develop a simpler and quicker alloantibody screening method, red cell stroma were bound and dried to microplate wells for use in magnetic-mixed passive haemagglutination (M-MPHA) tests. In the procedure of drying stroma, the Triton X-100-based haemolysing method gave lowest denaturation of red blood cells, and this method gave increased reactivity to Kidd and Rh antigens and clinically significant antibodies were detected as well as with the M-MPHA test. But long incubation with Triton X-100 and using high concentrations of Triton X-100 gave rise to some reduction in antigenicity, so the precise conditions for haemolysis are critical. This dried stroma-coated microplate can be stored for longer and more easily at room temperature than nondried intact red blood cells. The new system gave good sensitivity and the overall test time was shortened and should give a particular advantage for mass screening and for automation of this test. PMID:10583889

  14. Vesicles and red blood cells in flow: From individual dynamics to rheology

    NASA Astrophysics Data System (ADS)

    Vlahovska, Petia M.; Podgorski, Thomas; Misbah, Chaouqi

    2009-11-01

    The rheology of suspensions of soft particles, such as red blood cells, is a long-standing problem in science and engineering due to the complex interplay between deformable microstructure and the macroscale flow. The major challenge stems from the free-boundary nature of the particle interface. Lipid bilayer membranes that envelop cells and vesicles are particularly complex interfaces because of their unusual mechanics: the molecularly thin membrane is a highly-flexible incompressible fluid sheet. As a result, particles made of closed lipid bilayers (red cells and vesicles) can exhibit richer dynamics than would capsules and drops. We overview the key experimental observations and recent advances in the theoretical modeling of the vesicles and red blood cells in flow. To cite this article: P.M. Vlahovska et al., C. R. Physique 10 (2009).

  15. "Keep the Beat" Healthy Blood Pressure Helps Prevent Heart Disease | NIH MedlinePlus the Magazine

    MedlinePlus

    ... Javascript on. Special Section: Healthy Blood Pressure "Keep the Beat": Healthy Blood Pressure Helps Prevent Heart Disease ... Contents Your blood pressure rises and falls during the day. But when it stays elevated over time, ...

  16. Kit for the rapid preparation of .sup.99m Tc red blood cells

    DOEpatents

    Richards, Powell; Smith, Terry D.

    1976-01-01

    A method and sample kit for the preparation of .sup.99m Tc-labeled red blood cells in a closed, sterile system. A partially evacuated tube, containing a freeze-dried stannous citrate formulation with heparin as an anticoagulant, allows whole blood to be automatically drawn from the patient. The radioisotope is added at the end of the labeling sequence to minimize operator exposure. Consistent 97% yields in 20 minutes are obtained with small blood samples. Freeze-dried kits have remained stable after five months.

  17. Association of Prehospital Shock Index and Trauma Bay Uncrossmatched Red Blood Cell Transfusion With Multiple Transfusion.

    PubMed

    Day, Darcy L; Anzelon, Kathleen M; Conde, Franscisco A

    2016-01-01

    Early resuscitation of bleeding trauma patients with multiple blood products improves outcome, yet transfusion initiation is not standardized. Shock index (heart rate/systolic blood pressure) and trauma bay uncrossmatched red blood cell (RBC) transfusion were evaluated for association with multiple transfusions, defined as 6 or more RBCs during the first 6 hrs of hospital presentation. A prehospital shock index of 1 was significantly associated with multiple transfusions (p = .02). Subjects receiving uncrossmatched RBCs required more RBCs during the first 6 hrs (10.3 units, p < .01). Consideration of these simple variables may help trauma nurses anticipate the potentially bleeding patient. PMID:26953537

  18. Method for extending the useful shelf-life of refrigerated red blood cells by flushing with inert gas

    DOEpatents

    Bitensky, Mark W.; Yoshida, Tatsuro

    1997-01-01

    Method using oxygen removal for extending the useful shelf-life of refrigerated red blood cells. A cost-effective, 4.degree. 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.degree. C. for prolonged periods of time is achieved by removing oxygen therefrom 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.

  19. Red blood cell transfusion strategies and Maximum surgical blood ordering schedule

    PubMed Central

    Iyer, Shivakumar S; Shah, Jignesh

    2014-01-01

    Blood transfusion is one of the practices that is in vogue because it expands blood volume and purportedly improves the oxygen carrying capacity. Despite this supposed physiological benefit, paradoxically, both anaemia and transfusion are independently associated with organ injury and increased morbidity. Historically, transfusion was used to maintain blood haemoglobin concentration above 10 g/dL and a haematocrit above 30%. There is now a greater emphasis on interventions to reduce the use of transfusion as it is a scarce and expensive resource with many serious adverse effects. Institutional maximum surgical blood ordering schedule algorithm developed with data analysis and consensus of surgeons, anaesthesiologists and blood banks can reduce the overuse of blood. A PubMed search was performed with search words/combination of words ‘erythrocyte transfusion, adverse effects, economics, mortality, therapy, therapeutic use and utilisation’. Search yielded a total of 1541 articles that were screened for clinical relevance for the purpose of this review. PMID:25535420

  20. Red blood cells initiate leukocyte rolling in postcapillary expansions: a lattice Boltzmann analysis.

    PubMed

    Sun, Chenghai; Migliorini, Cristiano; Munn, Lance L

    2003-07-01

    Leukocyte rolling on the vascular endothelium requires initial contact between leukocytes circulating in the blood and the vessel wall. Although specific adhesion mechanisms are involved in leukocyte-endothelium interactions, adhesion patterns in vivo suggest other rheological mechanisms also play a role. Previous studies have proposed that the abundance of leukocyte rolling in postcapillary venules is due to interactions between red blood cells (RBCs) and leukocytes as they enter postcapillary expansions, but the details of the fluid dynamics have not been elucidated. We have analyzed the interactions of red and white blood cells as they flow from a capillary into a postcapillary venule using a lattice Boltzmann approach. This technique provides the complete solution of the flow field and quantification of the particle-particle forces in a relevant geometry. Our results show that capillary-postcapillary venule diameter ratio, RBC configuration, and RBC shape are critical determinants of the initiation of cell rolling in postcapillary venules. The model predicts that an optimal configuration of the trailing red blood cells is required to drive the white blood cell to the wall. PMID:12829477

  1. Red Blood Cells Initiate Leukocyte Rolling in Postcapillary Expansions: A Lattice Boltzmann Analysis

    PubMed Central

    Sun, Chenghai; Migliorini, Cristiano; Munn, Lance L.

    2003-01-01

    Leukocyte rolling on the vascular endothelium requires initial contact between leukocytes circulating in the blood and the vessel wall. Although specific adhesion mechanisms are involved in leukocyte-endothelium interactions, adhesion patterns in vivo suggest other rheological mechanisms also play a role. Previous studies have proposed that the abundance of leukocyte rolling in postcapillary venules is due to interactions between red blood cells (RBCs) and leukocytes as they enter postcapillary expansions, but the details of the fluid dynamics have not been elucidated. We have analyzed the interactions of red and white blood cells as they flow from a capillary into a postcapillary venule using a lattice Boltzmann approach. This technique provides the complete solution of the flow field and quantification of the particle-particle forces in a relevant geometry. Our results show that capillary-postcapillary venule diameter ratio, RBC configuration, and RBC shape are critical determinants of the initiation of cell rolling in postcapillary venules. The model predicts that an optimal configuration of the trailing red blood cells is required to drive the white blood cell to the wall. PMID:12829477

  2. Comparison of blood flow to the cutaneous temperature and redness after topical application of benzyl nicotinate

    NASA Astrophysics Data System (ADS)

    Jacobi, Ute; Kaiser, Marco; Koscielny, Jürgen; Schuetz, Rijk; Meinke, Martina C.; Sterry, Wolfram; Lademann, Jürgen

    2006-01-01

    The topical application of drugs, such as nicotinates, affects cutaneous blood flow. Such a biological response, which is dependent on the drug and the individual, can be measured noninvasively using laser Doppler flowmetry. We illustrate the kinetics of vasodilation caused by topically applied benzyl nicotinate using a new frequency-selective laser Doppler flowmeter. This flowmeter measures the blood flow in the superficial dermal plexus and the deeper lying larger capillaries simultaneously and indirectly by determining the flow velocity. Both sets of data are compared with the skin temperature and redness. Four biological parameters are measured consecutively on a skin area treated with gel containing benzyl nicotinate and on an untreated control area. A linear relationship between both blood flows is observed. However, no correlation is obtained between the microcirculation with either the cutaneous temperature or the redness. These results indicate the transport of the drug in the blood from the upper to the deeper capillaries. Cutaneous temperature and redness are unsuitable parameters to measure the kinetics of the blood flow after topical application of drugs.

  3. 99mTc red blood cell scintigraphy in evaluating focal liver lesions

    SciTech Connect

    Rabinowitz, S.A.; McKusick, K.A.; Strauss, H.W.

    1984-07-01

    To determine the accuracy of blood-pool imaging in the diagnosis of hepatic hemangiomas, 39 patients with various focal hepatic lesions were studied. The diagnoses in these patients were made by biopsy, angiography, surgical exploration, or clinical stability for a minimum of 14 months. The diagnoses were: hemangiomas (13 patients), hepatoma (three), metastases (19), abscesses (two), and liver cysts (two). After modified in vivo labeling of red blood cells with 20 mCi (740 MBq) of 99mTc pertechnetate, an initial flow study and early (1-15 min) and delayed (1-2 hr) static images were obtained. Increased blood-pool activity with a discordant flow pattern was seen in 11 of 13 patients with hemangiomas. False-negative scans occurred in two hemangiomas with extensive fibrosis. Two of three hepatomas had increased blood-pool activity associated with increased flow in a pattern identical to the increased blood-pool activity. None of the metastatic, abscess, or cystic lesions had increased blood-pool activity at any time after injection. It is concluded that 99mTc red blood cell imaging can distinguish hemangiomas from other focal liver lesions.

  4. Red Blood Cells Preconditioned with Hemin Are Less Permissive to Plasmodium Invasion In Vivo and In Vitro

    PubMed Central

    Gaudreault, Véronique; Wirbel, Jakob; Jardim, Armando; Rohrbach, Petra; Scorza, Tatiana

    2015-01-01

    Malaria is a parasitic disease that causes severe hemolytic anemia in Plasmodium-infected hosts, which results in the release and accumulation of oxidized heme (hemin). Although hemin impairs the establishment of Plasmodium immunity in vitro and in vivo, mice preconditioned with hemin develop lower parasitemia when challenged with Plasmodium chabaudi adami blood stage parasites. In order to understand the mechanism accounting for this resistance as well as the impact of hemin on eryptosis and plasma levels of scavenging hemopexin, red blood cells were labeled with biotin prior to hemin treatment and P. c. adami infection. This strategy allowed discriminating hemin-treated from de novo generated red blood cells and to follow the infection within these two populations of cells. Fluorescence microscopy analysis of biotinylated-red blood cells revealed increased P. c. adami red blood cells selectivity and a decreased permissibility of hemin-conditioned red blood cells for parasite invasion. These effects were also apparent in in vitro P. falciparum cultures using hemin-preconditioned human red blood cells. Interestingly, hemin did not alter the turnover of red blood cells nor their replenishment during in vivo infection. Our results assign a function for hemin as a protective agent against high parasitemia, and suggest that the hemolytic nature of blood stage human malaria may be beneficial for the infected host. PMID:26465787

  5. Laser viability method for red blood cell-state monitoring

    NASA Astrophysics Data System (ADS)

    Lapotko, Dmitry; Kuchinsky, Georgy; Antonishina, Elena; Scoromnik, Elena

    1996-01-01

    The method for RBC state control is based upon single cell viability control after illumination with laser pulse. Heat shock resulting from absorption of laser energy by a cell is considered as a cell load. This load acts from inside of the cell, is pulsed (10-5) and can be delivered directly to the chosen cells. The result of each illumination as cell survival or damage is controlled optically by monitoring the cells' response on a pulse through photothermal technique. Under fixed laser parameters the percentage of damaged cells is viability index (VI) for a certain cell population. The testing procedure includes consequential illumination of each cell in population and calculation of VI. Experimental set up is based upon optical microscope. Dual laser thermal lens technique is used for cell illumination and monitoring. For cell loading 5 ns pulses, 400 divided by 600 nm with energies up to 20 (mu) J are generated by tunable dye laser. Cell monitoring is realized with cw He-Ne (632.8 nm) laser and photodetector. All data acquisition routines are automated. Up to 3 cell suspensions can be studied in a multisample chamber designed to secure cells. An amount of cell suspension required is 1 (mu) l. One population test at a fixed wavelength takes 2 divided by 3 min. In experiments with rats, treated with LPS E. Coli injection to stimulate fever and a septic stress we found that variation of RBC viability becomes apparent in 20 - 30 min after injection, while the clinical changes (blood pressure, body temperature, skin temperature) become detectable after 1 hour. The results obtained show that the method can reveal additional properties of the cells most abundant for monitoring and diagnostic tasks.

  6. Peripheral red blood cell split chimerism as a consequence of intramedullary selective apoptosis of recipient red blood cells in a case of sickle cell disease.

    PubMed

    Marziali, Marco; Isgrò, Antonella; Sodani, Pietro; Gaziev, Javid; Fraboni, Daniela; Paciaroni, Katia; Gallucci, Cristiano; Alfieri, Cecilia; Roveda, Andrea; De Angelis, Gioia; Cardarelli, Luisa; Ribersani, Michela; Andreani, Marco; Lucarelli, Guido

    2014-01-01

    Allogeneic cellular gene therapy through hematopoietic stem cell transplantation is the only radical cure for congenital hemoglobinopathies like thalassemia and sickle cell anemia. Persistent mixed hematopoietic chimerism (PMC) has been described in thalassemia and sickle cell anemia. Here, we describe the clinical course of a 6-year-old girl who had received bone marrow transplant for sickle cell anemia. After the transplant, the patient showed 36% donor hematopoietic stem cells in the bone marrow, whereas in the peripheral blood there was evidence of 80% circulating donor red blood cells (RBC). The analysis of apoptosis at the Bone Marrow level suggests that Fas might contribute to the cell death of host erythroid precursors. The increase in NK cells and the regulatory T cell population observed in this patient suggests that these cells might contribute to the condition of mixed chimerism. PMID:25408852

  7. Peripheral Red Blood Cell Split Chimerism as a Consequence of Intramedullary Selective Apoptosis of Recipient Red Blood Cells in a Case of Sickle Cell Disease

    PubMed Central

    Marziali, Marco; Isgrò, Antonella; Sodani, Pietro; Gaziev, Javid; Fraboni, Daniela; Paciaroni, Katia; Gallucci, Cristiano; Alfieri, Cecilia; Roveda, Andrea; De Angelis, Gioia; Cardarelli, Luisa; Ribersani, Michela; Andreani, Marco; Lucarelli, Guido

    2014-01-01

    Allogeneic cellular gene therapy through hematopoietic stem cell transplantation is the only radical cure for congenital hemoglobinopathies like thalassemia and sickle cell anemia. Persistent mixed hematopoietic chimerism (PMC) has been described in thalassemia and sickle cell anemia. Here, we describe the clinical course of a 6-year-old girl who had received bone marrow transplant for sickle cell anemia. After the transplant, the patient showed 36% donor hematopoietic stem cells in the bone marrow, whereas in the peripheral blood there was evidence of 80% circulating donor red blood cells (RBC). The analysis of apoptosis at the Bone Marrow level suggests that Fas might contribute to the cell death of host erythroid precursors. The increase in NK cells and the regulatory T cell population observed in this patient suggests that these cells might contribute to the condition of mixed chimerism. PMID:25408852

  8. Conductometric study of shear-dependent processes in red cell suspensions. I. Effect of red blood cell aggregate morphology on blood conductance.

    PubMed

    Pribush, A; Meyerstein, D; Meyerstein, N

    2004-01-01

    The conductance and capacitance of flowing and quiescent red blood cell (RBC) suspensions were measured at a frequency of 0.2 MHz. The results demonstrate that the time-dependent changes in the conductance recorded during the aggregation process differ in nature for suspensions of short linear rouleaux, branched aggregates and RBC networks. It is shown that the conductance of RBC suspensions measured during the aggregation and disaggregation processes follows the morphological transformations of the RBC aggregates. Thus, this method enables characterization of the morphology of RBC aggregates formed in whole blood and in suspensions with physiological hematocrits both under flow conditions and in stasis. These results in combination with previous ones suggest that this technique can be used for studies of dynamic RBC aggregation and probably for diagnostic use. PMID:14967887

  9. [Structure of cytosolic membrane and chemical composition of red blood cells during the early period of wound damage according to scanning probe microscopy].

    PubMed

    Belousova, O D; Gaĭdash, A A; Tolmachev, I A; Ivchenko, E V; Golubok, A O; Levichev, V V; Mukhin, I S; Zhukov, M V; Belousov, I S; Tkachuk, I V

    2013-01-01

    With the help of scanning electronic and atomic force microscopy structure of red blood cell membranes of the system blood-groove and microcirculatory channels is studied. It is established, that in early stages of skin wounds in a peripheral blood circulation appear compressed red blood cells, losing water. As a result the basic mechanism of destruction of red blood cell membranes are interlayered shifts and stratification. In red blood cells of microvasculature, on the contrary, red blood cells in state of vacuolar degeneration are indentified. It creates preconditions for hydration and bullous deformations of membranes. Porous structures of membranes of both types erythrocytes are exposed to expansion. PMID:23805624

  10. Immunosuppressive protocols for transplantation and certain hematologic malignancies can prevent the primary immune response to the D blood group antigen.

    PubMed

    Seager, Adair; Sandler, S G

    2013-01-01

    A review of the published literature on Rh alloimmunization reveals that its incidence varies with the volume of infused D+ red blood cells (RBCs), the probable Rh genotype of the RBCs, and the immune competency of the D- recipient. Among the reports of Rh alloimmunization on different clinical circumstances, we identified five studies in which a combined total of 62 D- recipients of hematopoetic stem cell or solid -organ transplants were transfised with D+ RBCs and none (0%) formed anti-D. The observation that immunosuppressive protocols developed to prevent rejection of tissue and organ transplants also prevented alloimmunization to the D blood group antigen raises the possibility of practical applications in blood transfusion practice. PMID:24325172

  11. Mapping viscoelastic properties of healthy and pathological red blood cells at the nanoscale level

    NASA Astrophysics Data System (ADS)

    Ciasca, G.; Papi, M.; di Claudio, S.; Chiarpotto, M.; Palmieri, V.; Maulucci, G.; Nocca, G.; Rossi, C.; de Spirito, M.

    2015-10-01

    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.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

  12. [Concentrated red blood cells transfusion in Yaoundé, Cameroon: what quality?].

    PubMed

    Mbanya, D; Nouthe, B; Tayou Tagny, C; Moudourou, S; Ngogang, J

    2007-11-01

    As part of a quality assurance process in the transfusion service of a hospital blood bank of Yaoundé, Cameroon, a selection of units of red cell concentrates (RCC) were evaluated for volume, haemoglobin, and haematocrit levels as well as blood cell content. Blood samples were all collected into standard double blood bags containing an anticoagulant, citrate-phosphate-dextrose and adenine. During a three-month period, 35 bags intended for the preparation of the RCC were analysed. After relevant screening for transfusion transmissible infections ,and ABO and rhesus (RH1) blood grouping, the bags were centrifuged to obtain RCC. The resultant red cell bags were weighed and the volumes estimated. Full blood counts were performed on samples of the RCC using an electronic particle counter (DIANA 5, HYCEL Diagnostics, Reims, France). The results obtained showed that, based on ISO 9001: 2000 norms, there were 57, 66 and 80% of RCC respectively with volumes, hemoglobin levels as well as hematocrit that were in conformity with the norms. When the data was analysed based on the Algerian norms, 83, 66 and 95% respectively conformed. The significance of these findings and the need for establishing local norms for quality assurance in our community are discussed. PMID:18295526

  13. Sorbitol determination by liquid chromatography: application to red blood cells of diabetic rats.

    PubMed

    Akanuma, H; Yamanouchi, T; Ono, H; Nomura, K; Akanuma, Y

    1985-02-01

    This report describes an application of liquid chromatography to the determination of sorbitol in red blood cells. The chromatograph employed in the present study was made up of sub- and main-separation systems and a detector portion. The sub-separation system was for concentration of polyols and involved two small columns, each containing the same anion exchange resin. The first was a tiny column which, in borate form, served as the concentrator of polyols and sugars charged in a large volume, while the second, in acetate form, separated the carbohydrates from the borate. The main system was for the fine separation of each carbohydrate and employed cation exchange columns. The detector part utilized a flow fluorometric method comprising two successive reactions: periodate oxidation followed by the Hantzsch reaction. The resulting whole chromatographic system was applied to the determination of sorbitol in red blood cells obtained from normal rats and rats made diabetic by the administration of streptozotocin; a part of the latter group had also received an aldose reductase inhibitor. Our results supported the concepts that a prolonged duration of high blood glucose level induces an elevated level of sorbitol inside red blood cells and that aldose reductase inhibitors are effective in reducing this level. PMID:3924905

  14. Modelling and rapid simulation of multiple red blood cell light scattering

    PubMed Central

    Zohdi, T.I; Kuypers, F.A

    2006-01-01

    The goal of this work is to develop a computational framework to rapidly simulate the light scattering response of multiple red blood cells. Because the wavelength of visible light (3.8×10−7 m≤λ≤7.2×10−7 m) is approximately an order of magnitude smaller than the diameter of a typical red blood cell scatterer (d≈8×10−6 m), geometric ray-tracing theory is applicable, and can be used to quickly ascertain the amount of optical energy, characterized by the Poynting vector, that is reflected and absorbed by multiple red blood cells. The overall objective is to provide a straightforward approach that can be easily implemented by researchers in the field, using standard desktop computers. Three-dimensional examples are given to illustrate the approach and the results compare quite closely to experiments on blood samples conducted at the Children's Hospital Oakland Research Institute (CHORI). PMID:17015301

  15. Cardiopulmonary Function following Transfusion of Three Red Blood Cell Products in Elective Abdominal Aortic Aneurysmectomy

    PubMed Central

    Krausz, Michael M.; Dennis, Richard C.; Utsunomiya, Takayoshi; Grindlinger, Gene A.; Vegas, Armando M.; Churchill, W. Hallowell; Mannick, John A.; Valeri, C. Robert; Hechtman, Herbert B.

    1981-01-01

    In order to evaluate the importance of red cell O2 affinity of transfused blood on cardiac performance and adverse effects of transfusion on lung function, a prospective double-blind protocol was used in 27 patients undergoing abdominal aortic aneurysmectomy. Three types of blood were administered: packed red cells (PC), washed red cells (WC) and high 2,3 DPG red cells (2,3 DPG). An average of 4.5 units of blood was used per patient. Transfusion of 2,3 DPG blood resulted in maintenance of in vivo P50 during surgery and an increase to 31.2 torr after operation (p < 0.001). An intraoperative fall in in vivo P50 to 23.2 ± 2.0 torr was observed in patients who were transfused with PC (p < 0.001) and to 25.1 ± 2.6 torr with WC (p < 0.005). A fall in body temperature averaging 2.2 C intraoperatively was noticed in all three groups. After operation, in vitro P50 decreased in patients transfused with PC (p < 0.005) and WC (p < 0.005) while it remained unchanged in the high 2,3 DPG group. This was consistent with the decrease of red cell 2,3 DPG in the PC (p < 0.001) and WC groups (p < 0.01) and maintenance in the 2,3 DPG group. Left ventricular stroke work and volume loading Starling type myocardial performance curves were similar for the three groups. Microaggregates measured by Coulter counting and screen filtration pressure were the same for all three products in samples drawn on both sides of the 40 µm transfusion filter. There was no relationship of transfusion volumes or type of blood product to changes in lung function (physiologic shunting, dynamic compliance and pulmonary arterial pressure) in the three groups of patients. The false negative, β, error of missing a true 25% difference was less than 10%. It is concluded that 2,3 DPG enriched red cells improved oxygen availability, but that a 4.5 unit transfusion of any of the three blood products did not influence lung function or myocardial performance following aneurysmectomy. ImagesFig. 2. PMID:7294931

  16. Alterations of the apparent area expansivity modulus of red blood cell membrane by electric fields.

    PubMed Central

    Katnik, C; Waugh, R

    1990-01-01

    Red blood cell membrane exhibits a large resistance to changes in surface area. This resistance is characterized by the area expansivity modulus K, which relates the isotropic membrane force resultant, T, to the fractional change in membrane surface area delta A/Ao. The experimental technique commonly used to determine K is micropipette aspiration. Using this method, E. A. Evans and R. Waugh (1977, Biophys. J. 20:307-313) obtained a value of 450 dyn/cm for the modulus. In the present report, it is shown that the value of K, as determined using this method, is affected by electric potential differences applied across the tip of the pipette. Using Ag-AgCl electrodes and current clamping electronics, we obtained values for K ranging from 150 dyn/cm with -1.0 V applied, to 1,500 dyn/cm with 1.0 V applied. At 0.0 V the modulus obtained was approximately 500 dyn/cm. A reversible, voltage- and pressure-dependent change in the cell volume probably accounts for the effect of the voltage on the calculated value of the modulus. The use of lanthanum chloride or increasing the extra- and intracellular solute concentrations reduced the voltage dependence of the measurements. It was also found that when dissimilar metals were used to "ground" the pipette to the chamber to prevent lysis of cells by static charge, values for K ranged from 121 to 608 dyn/cm. Based on measurements made at zero applied volts, in the presence of 0.4 mM lanthanum and at high solute concentration, we conclude that the true value of the modulus is approximately 500 dyn/cm. PMID:2344470

  17. Red Blood Cell Transfusions Impact Pneumonia Rates After Coronary Artery Bypass Grafting Surgery

    PubMed Central

    Likosky, Donald S.; Paone, Gaetano; Zhang, Min; Rogers, Mary A.M.; Harrington, Steven D.; Theurer, Patricia F.; DeLucia, Alphonse; Fishstrom, Astrid; Camaj, Anton; Prager, Richard L.

    2016-01-01

    Background Pneumonia, a known complication of coronary artery bypass (CABG) surgery, significantly increases a patient’s risk of morbidity and mortality. While not well characterized, red blood cell transfusions (RBC) may increase a patient’s risk of pneumonia. We describe the relationship between RBC transfusion and post-operative pneumonia after CABG surgery. Methods A total of 16,182 consecutive patients underwent isolated CABG surgery between 2011 and 2013 at one of 33 hospitals in the state of Michigan. We used multivariable logistic regression to estimate the odds of pneumonia associated with the use or number (0, 1, 2, 3, 4, 5, >6) of RBC units. We adjusted for predicted risk of mortality, pre-operative hematocrit, history of pneumonia, cardiopulmonary bypass duration and medical center. We confirmed the strength and direction of these relationships among selected clinical subgroups in a secondary analysis. Results 576 (3.6%) patients developed pneumonia and 6,451 (39.9%) received RBC transfusions. There was a significant association between any RBC transfusion and pneumonia (ORadj 3.4, p<0.001). There was a dose-response between number of units and odds of pneumonia, ptrend<0.001. Patients receiving only 2 units of RBCs had twofold (ORadj 2.1, p<0.001) increased odds of pneumonia. These findings were consistent across clinical subgroups. Conclusions We found a significant, volume-dependent association between an increasing number of RBCs and odds of pneumonia, which persisted after adjusting for pre-operative patient characteristics. Clinical teams should explore opportunities for preventing a patient’s risk of RBC transfusions, including reducing hemodilution or adopting a lower transfusion threshold in a stable patient. PMID:26209489

  18. Evaluating red-cockaded woodpeckers for exposure to West Nile Virus and blood parasites

    USGS Publications Warehouse

    Dusek, R.J.; Richardson, D.; Egstad, K.F.; Heisey, Dennis M.

    2006-01-01

    A marked decline in the Picoides borealis (Red-cockaded Woodpecker [RCW]) population at Noxubee National Wildlife Refuge, MS, was observed in 2002. Demographic changes - including absence of hatch-year birds, decreases in size of known groups, and loss of known groups-were identified during annual fall surveys and are uncharacteristic of RCW populations. In 2003, a serosurvey of 28 adult RCWs was conducted to investigate the presence of West Nile virus (WNV) exposure in the population, possibly providing insight into whether WNV may have been responsible for this decline. Blood smears were also examined from these birds for blood parasites. We found no evidence of West Nile virus exposure or blood parasites in any of the RCWs sampled. Further monitoring of the RCW population and WNV activity in other species at Noxubee NWR is recommended to further evaluate the potential role of WNV and blood parasites in their decline.

  19. Occlusion of Small Vessels by Malaria-Infected Red Blood Cells

    NASA Astrophysics Data System (ADS)

    Lei, Huan; Fedosov, Dmitry; Caswell, Bruce; Karniadakis, George

    2010-11-01

    We use dissipative particle dynamics (DPD) method to study malaria-infected red blood cells (i-RBC). We have developed a multi-scale model to describe both static and dynamic properties of RBCs. With this model, we study the adhesive interaction between RBCs as well as the interaction between the Plasmodium falciparum (Pf)-parasitized cells and a vessel wall coated with purified ICAM-1. In this talk, we will discuss the effect of the Pf-parasitized malaria cell on the flow resistance of the blood flow at different parasetimia levels. The blood flow in malaria disease shows high flow resistance as compared with the healthy case due to both the stiffening of the i-RBCs (up to ten times) as well as the adhesion dynamics. For certain sizes of of small vessels, the malaria-infected cells can even lead to occlusion of the blood flow, in agreement with recent experiments.

  20. Heme oxygenase-1 deficiency alters erythroblastic island formation, steady-state erythropoiesis and red blood cell lifespan in mice

    PubMed Central

    Fraser, Stuart T.; Midwinter, Robyn G.; Coupland, Lucy A.; Kong, Stephanie; Berger, Birgit S.; Yeo, Jia Hao; Andrade, Osvaldo Cooley; Cromer, Deborah; Suarna, Cacang; Lam, Magda; Maghzal, Ghassan J.; Chong, Beng H.; Parish, Christopher R.; Stocker, Roland

    2015-01-01

    Heme oxygenase-1 is critical for iron recycling during red blood cell turnover, whereas its impact on steady-state erythropoiesis and red blood cell lifespan is not known. We show here that in 8- to 14-week old mice, heme oxygenase-1 deficiency adversely affects steady-state erythropoiesis in the bone marrow. This is manifested by a decrease in Ter-119+-erythroid cells, abnormal adhesion molecule expression on macrophages and erythroid cells, and a greatly diminished ability to form erythroblastic islands. Compared with wild-type animals, red blood cell size and hemoglobin content are decreased, while the number of circulating red blood cells is increased in heme oxygenase-1 deficient mice, overall leading to microcytic anemia. Heme oxygenase-1 deficiency increases oxidative stress in circulating red blood cells and greatly decreases the frequency of macrophages expressing the phosphatidylserine receptor Tim4 in bone marrow, spleen and liver. Heme oxygenase-1 deficiency increases spleen weight and Ter119+-erythroid cells in the spleen, although α4β1-integrin expression by these cells and splenic macrophages positive for vascular cell adhesion molecule 1 are both decreased. Red blood cell lifespan is prolonged in heme oxygenase-1 deficient mice compared with wild-type mice. Our findings suggest that while macrophages and relevant receptors required for red blood cell formation and removal are substantially depleted in heme oxygenase-1 deficient mice, the extent of anemia in these mice may be ameliorated by the prolonged lifespan of their oxidatively stressed erythrocytes. PMID:25682599

  1. Developing red cell flow orientation shown by changes in blood reflectivity.

    PubMed

    McMillan, D E; Utterback, N G; Lee, M M

    1988-01-01

    The rate of onset of erythrocyte flow orientation at normal concentration has not previously been established. Reflectivity of blood and resuspended non-aggregated red cells at normal (41%) and elevated (60%) hematocrit has been used to examine this process. Video recordings were made before, during, and after shearing by bob motion in a cylinder-in-cylinder viscometer at shear rates ranging from 4 to 100 inverse seconds. Unaggregated erythrocytes in PBS, already more reflective than blood before shearing, became even more reflective during shearing even at the lowest shear rate studied. The time required for the increased reflectivity to stabilize was observed to be inversely proportional to shear rate for both blood and resuspended red cells. Reflection became constant after a total shear strain (bob shear rate x time) from 4 to 10 at all shear rates studied. Onset of increased reflection expressed in total shear strain units (an index of overall bob movement) was independent of shear rate in the absence of aggregation. When red cells were studied in native plasma, reflectivity increased as much as 30% during shearing, but always remained below unaggregated red cell reflectivity for the same hematocrit and shear rate. Greater reflectivity of unaggregated red cells persisted after cessation of shearing, while blood's reflectivity dropped progressively over several seconds to its pre-shearing value. The geometry chosen for study and insensitivity to light source composition indicate that specular reflection by red cells near the cup's inner surface is responsible for the increased light return during flow. Maximal rate of rise in reflectivity at all shear rates studied was observed to coincide with blood's previously reported transient shear stress overshoot and to correspond with an overall bob motion that would rotate suspended particles approximately 45 degrees. The close relation of both reflectivity increase and shear stress overshoot to such modest overall

  2. A mesoscopic simulation on distributions of red blood cells in a bifurcating channel

    NASA Astrophysics Data System (ADS)

    Inoue, Yasuhiro; Takagi, Shu; Matsumoto, Yoichiro

    2004-11-01

    Transports of red blood cells (RBCs) or particles in bifurcated channels have been attracting renewed interest since the advent of concepts of MEMS for sorting, analyzing, and removing cells or particles from sample medium. In this talk, we present a result on a transport of red blood cells (RBCs) in a bifurcating channel studied by using a mesoscale simulation technique of immiscible droplets, where RBCs have been modeled as immiscible droplets. The distribution of RBCs is represented by the fractional RBC flux into two daughters as a function of volumetric flow ratio between the daughters. The data obtained in our simulations are examined with a theoretical prediction, in which, we assume an exponential distribution for positions of RBCs in the mother channel. The theoretical predictions show a good agreement with simulation results. A non-uniform distribution of RBCs in the mother channel affects disproportional separation of RBC flux at a bifurcation.

  3. Red Kidney: Kidney Transplant From a Deceased Donor Who Received Massive Blood Transfusion During Cardiopulmonary Bypass.

    PubMed

    Bell, Richard; Hanif, Faisal; Prasad, Padmini; Ahmad, Niaz

    2016-06-01

    Here, we present a case of a deceased-donor kidney transplant. The brain-dead donor had received a massive blood transfusion during cardiopulmonary bypass, which lead to hemolysis, hemoglobinuria, acute kidney injury, and renal replacement therapy. The kidney appeared red after in situ flush. Postoperatively, the recipient developed delayed graft function. Protocol biopsy during the postoperative period revealed the widespread deposition of heme pigment in the renal tubules. Massive blood transfusion and cardiopulmonary bypass surgery are associated with hemolysis and heme pigment deposition in the renal tubules, which subsequently lead to acute kidney injury. Kidneys from such donors appear red and, while this does not preclude transplant, are likely to develop delayed graft function. PMID:26030717

  4. Numerical simulation of rheology of red blood cell rouleaux in microchannels

    NASA Astrophysics Data System (ADS)

    Wang, T.; Pan, T.-W.; Xing, Z. W.; Glowinski, R.

    2009-04-01

    An elastic spring model is applied to simulate the skeletal structure of the red blood cell (RBC) membrane and to study the dynamical behaviors of the red blood cell rouleaux (aggregates) in microchannels. The biconcave shape of RBCs in static plasma and the tank-treading phenomenon of single RBCs in simple shear flows have been successfully captured using this model. The aggregation and dissociation of RBCs with different deformability have been investigated in both shear and Poiseuille flows by taking into consideration the rheology of the cells and the intercellular interaction kinetics. It is found that the equilibrium configuration of the rouleaux formed under no-flow condition, the motion of the rouleaux in the flows, and the rheological behavior of individual cells in the rouleaux is closely related to the intercellular interaction strength, hydrodynamic viscous forces, and the deformability of the cell membrane.

  5. Numerical simulation of rheology of red blood cell rouleaux in microchannels.

    PubMed

    Wang, T; Pan, T-W; Xing, Z W; Glowinski, R

    2009-04-01

    An elastic spring model is applied to simulate the skeletal structure of the red blood cell (RBC) membrane and to study the dynamical behaviors of the red blood cell rouleaux (aggregates) in microchannels. The biconcave shape of RBCs in static plasma and the tank-treading phenomenon of single RBCs in simple shear flows have been successfully captured using this model. The aggregation and dissociation of RBCs with different deformability have been investigated in both shear and Poiseuille flows by taking into consideration the rheology of the cells and the intercellular interaction kinetics. It is found that the equilibrium configuration of the rouleaux formed under no-flow condition, the motion of the rouleaux in the flows, and the rheological behavior of individual cells in the rouleaux is closely related to the intercellular interaction strength, hydrodynamic viscous forces, and the deformability of the cell membrane. PMID:19518265

  6. Haemoglobin content modulated deformation dynamics of red blood cells on a compact disc.

    PubMed

    Kar, Shantimoy; Ghosh, Uddipta; Maiti, Tapas Kumar; Chakraborty, Suman

    2015-12-21

    We investigate the deformation characteristics of red blood cells (RBCs) on a rotating compact disc platform. Our study brings out the interplay between haemoglobin content and RBC deformability in a centrifugally actuated microfluidic environment. We reveal that RBC deformations follow the similar trend of principal stress distributed throughout the radial direction, rendering an insight into the mechano-physical processes involved. This study can be used as a diagnostic marker to determine haematological disorders in diseased blood samples tested on compact disc based microfluidic platforms. PMID:26502076

  7. Application of gelatin zymography for evaluating low levels of contaminating neutrophils in red blood cell samples.

    PubMed

    Achilli, Cesare; Ciana, Annarita; Balduini, Cesare; Risso, Angela; Minetti, Giampaolo

    2011-02-15

    Supposedly "homogeneous" red blood cell (RBC) samples are commonly obtained by "washing" whole blood free of plasma, platelets, and white cells with physiological solutions, a procedure that does not result, however, in sufficient removal of polymorphonuclear neutrophils (PMNs), leading to possible artifactual results. Pure RBC samples can be obtained only by leukodepletion procedures. Proposed here is a version of gelatin zymography adapted to detect matrix metalloproteinase 9 (MMP-9), selectively expressed by PMNs, in heterogeneous mixtures of RBCs and PMNs that can reveal contamination at levels as low as 1 PMN/10⁶ RBCs. PMID:20971053

  8. Effects of Poloxamer 188 on red blood cell membrane properties in sickle cell anaemia.

    PubMed

    Sandor, Barbara; Marin, Mickaël; Lapoumeroulie, Claudine; Rabaï, Miklos; Lefevre, Sophie D; Lemonne, Nathalie; El Nemer, Wassim; Mozar, Anaïs; Français, Olivier; Le Pioufle, Bruno; Connes, Philippe; Le Van Kim, Caroline

    2016-04-01

    Vaso-occlusive crisis (VOC) is the main acute complication in sickle cell anaemia (SS) and several clinical trials are investigating different drugs to improve the clinical severity of SS patients. A phase III study is currently exploring the profit of Velopoloxamer in SS during VOCs. We analysed, in-vitro, the effect of poloxamer (P188) on red blood cell (RBC) properties by investigating haemorheology, mechanical and adhesion functions using ektacytometry, microfluidics and dynamic adhesion approaches, respectively. We show that poloxamer significantly reduces blood viscosity, RBC aggregation and adhesion to endothelial cells, supporting the beneficial use of this molecule in SS therapy. PMID:26846309

  9. /sup 99m/Tc red blood cell scintigraphy in evaluating focal liver lesions

    SciTech Connect

    Rabinowitz, S.A.; McKusick, K.A.; Strauss, H.W.

    1984-07-01

    To determine the accuracy of blood-pool imaging in the diagnosis of hepatic hemangiomas, 39 patients with various focal hepatic lesions were studied. The diagnoses in these patients were made by biopsy, angiography, surgical exploration, or clinical stability for a minimum of 14 months. The diagnoses were: hemangiomas (13 patients), hepatoma (three), metastases (19), abscesses (two), and liver cysts (two). After modified in vivo labeling of red blood cells with 20 mCi (740 MBq) of /sup 99m/Tc pertechnetate, an initial flow study and early (1-15 min) and delayed (1-2 hr) static images were obtained. Increased blood-pool activity with a discordant flow pattern was seen in 11 of 13 patients with hemangiomas. False-negative scans occurred in two hemangiomas with extensive fibrosis. None of the metastatic, abscess, or cystic lesions had increased blood-pool activity at any time after injection. It is concluded that /sup 99m/Tc red blood cell imaging can distinguish hemangiomas from other focal liver lesions.

  10. Speckle-based measurement of the light scattering by red blood cells in vivo

    NASA Astrophysics Data System (ADS)

    Fine, I.; Kaminsky, A.

    2011-03-01

    Optical spectroscopy approach, using non-coherent light sources, has become an important tool for non-invasive analysis in vivo. It is based on the assumption that biochemical characteristics of biological system can be determined through the optical coefficients of blood and tissue particles. Thus, in the framework of this approach, the major concern is to express the obtained optical signals in terms the optical coefficients of the single particle of blood or tissue. However, since the light propagation in tissue is dominated by the multiple-scattering component, a direct measurement of single scattering characteristics turns to be a very difficult task. Practically, only the relative changes of absorption and scattering coefficients are measured. We suggested to adopt the dynamic light scattering (DLS) or speckle technique for the determination of the light scattering coefficients of the red blood cells under stasis conditions in vivo. We assumed that under zero flow conditions the RBC movement is driven mostly by the Brownian motion. It was shown, that under appropriate measurement geometry, the measured optical signal can be decomposed into a few major components. The most dominant components are ascribed to the single backscattering and forward scattering coefficients of the red blood cells. In-vitro and in vivo experimental tests have shown a good correspondence between the theoretically estimated and experientially measured results. The obtained results indicate that the DLS technique can be adopted for the determination of blood particles scattering characteristics in addition to the movement and effective viscosity parameters measurement in vivo.

  11. Continuous and noninvasive hemoglobin monitoring reduces red blood cell transfusion during neurosurgery: a prospective cohort study.

    PubMed

    Awada, Wael N; Mohmoued, Maher F; Radwan, Tarek M; Hussien, Gomaa Z; Elkady, Hany W

    2015-12-01

    Continuous, noninvasive hemoglobin (SpHb) monitoring provides clinicians with the trending of changes in hemoglobin, which has the potential to alter red blood cell transfusion decision making. The objective of this study was to evaluate the impact of SpHb monitoring on blood transfusions in high blood loss surgery. In this prospective cohort study, eligible patients scheduled for neurosurgery were enrolled into either a Control Group or an intervention group (SpHb Group). The Control Group received intraoperative hemoglobin monitoring by intermittent blood sampling when there was an estimated 15% blood loss. If the laboratory value indicated a hemoglobin level of ≤10 g/dL, a red blood cell transfusion was started and continued until the estimated blood loss was replaced and a laboratory hemoglobin value was >l0 g/dL. In the SpHb Group patients were monitored with a Radical-7 Pulse CO-Oximeter for continuous noninvasive hemoglobin values. Transfusion was started when the SpHb value fell to ≤l0 g/dL and was continued until the SpHb was ≥l0 g/dL. Blood samples were taken pre and post transfusion. Percent of patients transfused, average amount of blood transfused in those who received transfusions and the delay time from the hemoglobin reading of <10 g/dL to the start of transfusion (transfusion delay) were compared between groups. The trending ability of SpHb, and the bias and precision of SpHb compared to the laboratory hemoglobin were calculated. Compared to the Control Group, the SpHb Group had fewer units of blood transfused (1.0 vs 1.9 units for all patients; p ≤ 0.001, and 2.3 vs 3.9 units in patients receiving transfusions; p ≤ 0.0 l), fewer patients receiving >3 units (32 vs 73%; p ≤ 0.01) and a shorter time to transfusion after the need was established (9.2 ± 1.7 vs 50.2 ± 7.9 min; p ≤ 0.00 l). The absolute accuracy of SpHb was 0.0 ± 0.8 g/dL and trend accuracy yielded a coefficient of determination of 0.93. Adding SpHb monitoring to

  12. Effects of storage on irradiated red blood cells: An in-vitro and in-vivo study. Master's thesis

    SciTech Connect

    Knoll, S.E.

    1991-08-01

    Irradiation of red blood cell units has recently become a topic of special concern as the result of increasing reports of graft versus host disease in immunocompetent blood transfusion recipients. This study was designed to evaluate the potassium elevations observed in stored irradiated red blood cells and to evaluate the in vivo survival of stored irradiated red blood cells using a dog model. In the in vitro study ten units of human CPDA-1 packed red blood cells were made into paired aliquots; one aliquot of each pair was irradiated with 3000 rads of gamma radiation and the potassium content measured at points throughout 35 days of storage. A significant increase in potassium levels in the irradiated aliquots was observed from the first day after irradiation and continued through the entire storage period.

  13. Red blood cell and leukocyte alloimmunization in patients awaiting kidney transplantation

    PubMed Central

    da Silva, Silvia Fernandes Ribeiro; Ferreira, Gláucia Maria; da Silva, Sonia Leite; Alves, Tânia Maria de Oliveira; Ribeiro, Ilana Farias; Ribeiro, Thyciana Rodrigues; Cavalcante, Maria do Carmo Serpa

    2013-01-01

    Objective To determine the rates of red blood cell and leukocyte alloimmunization in patients with chronic kidney disease awaiting kidney transplantation. Methods In this cross-sectional and prospective study, the serum of 393 chronic kidney disease patients on a transplant waiting list in Ceará, Northeastern Brazil were tested for red cell and leukocyte antibodies. In addition, demographic, clinical and laboratory data were collected. Results The average age in the sample of 393 patients was 34.1 ± 14 years. Slightly more than half (208; 52.9%) were male. The average numbers of transfusions and gestations were 3.1 ± 3.3 and 1.6 ± 6, respectively. One third (33.6%) were alloimmunized: 78% with leukocyte antibodies, 9.1% with red cell antibodies and 12.9% with both. Red cell antibodies were detected in 29 cases (7.4%), 17 of whom were women, who had received more transfusions than the males (p-value < 0.0001). The most frequently detected red cell antibodies belonged to the Rh (24.1%) and Kell (13.8%) blood group systems. Leukocyte antibodies were detected in 30.5% of cases, 83 of whom were women, who had received more transfusions than the males (p-value < 0.0001) and were more reactive to panel reactive antibodies (p-value < 0.0001). The mean alloreactivity to panel reactive antibodies was 47.7 ± 31.2%. Conclusion Chronic kidney disease patients on the transplant waiting list in Ceará, Brazil, display high rates of red cell (7.4%) and leukocyte (30.5%) alloimmunization. In this sample, alloimmunization was significantly associated with the number of transfusions and gender. PMID:23904808

  14. Photometric determination of phenomenological correlation between osmotic behavior and hemolysis of red blood cells.

    PubMed

    Yang, X S; Kamino, K

    1995-01-01

    The osmotic behavior of red blood cells from a human and from several other mammalian species was studied by photometric measurements. When red blood cells were suspended in sodium chloride solutions with various osmotic concentrations, the optical density at 620 nm was reciprocally related to the relative volume of the red cells. Thus, we evaluated the osmotic volume changes in the red cells from optical density measurements. The Boyle-van't Hoff relation was applicable to the osmotic behavior of red cells which responded as a complete osmometer in hypertonic and slightly hypotonic (lower than about 240 mOsm) solutions. Also, we examined the rheological correlation between osmotic volume changes and hemolysis. Osmotic hemolysis occurred corresponding to breakdown of the Boyle-van't Hoff relation in hypotonic solutions. The critical osmotic concentration for the breakdown of the Boyle-van't Hoff relation was that for osmotic hemolysis. In Na2SO4 solutions, although the critical osmotic concentration shifted towards a smaller value, the critical volume for the breakdown of the Boyle-van't Hoff relation and for osmotic hemolysis was maintained at a constant value, indicating that the onset of osmotic hemolysis depends exclusively upon the critical volume. In the samples from a human, the critical volume for the onset of hemolysis was estimated to be 1.25 +/- 0.05 in the ratio to the normal volume in iso-osmotic solution. From these obtained results, it is suggested that the red cell behaves in hypotonic solutions as a viscoelastic body of the type represented by the Voigt model, and the viscoelastic breakdown of the membrane results in osmotic hemolysis in hypotonic solution. PMID:8713172

  15. Characterizations of individual human red blood cells from patients with diabetes mellitus (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Lee, SangYun; Jang, Seongsoo; Park, HyunJoo; Park, YongKeun

    2016-03-01

    We systematically measure the morphological, biochemical, and biomechanical properties of individual human red blood cells (RBCs) from patients with diabetes mellitus using quantitative phase imaging technique to characterize the diabetic red cells with respect to those of the healthy. The 3-D refractive index tomograms and 2-D dynamic membrane fluctuation maps of individual RBCs are reconstructed from a set of the retrieved complex optical fields at various laser incidence angles using the Common-path diffraction optical tomography, from which volume, surface area, sphericity, hemoglobin (Hb) concentration, Hb content, and membrane fluctuation are obtained simultaneously. The correlative relations among the retrieved red cell indices of diabetic and healthy RBCs are also investigated with capabilities of individual cell measurement. As expected, there are no significant alterations in morphologies (cellular volumes, surface area, and sphericity) between diabetic and healthy RBCs. However, despite the minute mean corpuscular Hb differences in cell blood count datasheet, the measured Hb concentrations and Hb contents of diabetic RBCs are statistically higher than those of healthy RBCs, which might be related to the glycation of Hb molecules by hyperglycemia. Meanwhile, the membrane fluctuations of diabetic RBCs are clearly diminished compared to healthy red cells, implying the significantly decreased RBC deformability. In particular, it seems that the membrane fluctuations have mild negative relationships with the reported HbA1c levels.

  16. Electrophoretic characterization of aldehyde-fixed red blood cells, kidney cells, lynphocytes and chamber coatings

    NASA Technical Reports Server (NTRS)

    1976-01-01

    Ground-based electrokinetic data on the electrophoresis flight experiment to be flown on the Apollo-Soyuz Test Project experiment MA-011 are stipulated. Aldehyde-fixed red blood cells, embryonic kidney cells and lymphocytes were evaluated by analytical particle electrophoresis. The results which aided in the interpretation of the final analysis of the MA-011 experiment are documented. The electrophoresis chamber surface modifications, the buffer, and the material used in the column system are also discussed.

  17. Digital holography for recovering 3D shape of red blood cells

    NASA Astrophysics Data System (ADS)

    Memmolo, P.; Miccio, L.; Merola, F.; Gennari, O.; Netti, P.; Ferraro, Pietro

    2015-07-01

    Full morphometric data analysis and 3D rendering of Red Blood Cells (RBCs) is provided by means of Digital Holography (DH) in combination with Optical Tweezers (OT). The proposed method is compared with a geometrical model of RBC in order to evaluate its accuracy and tested for many kinds of RBCs, from healthy ones with double-concavity to that with abnormal shapes. Applications in diagnostics are foreseen.

  18. Simultaneous determination of size and refractive index of red blood cells by light scattering measurements

    SciTech Connect

    Ghosh, N.; Buddhiwant, P.; Uppal, A.; Majumder, S.K.; Patel, H.S.; Gupta, P.K.

    2006-02-20

    We present a fast and accurate approach for simultaneous determination of both the mean diameter and refractive index of a collection of red blood cells (RBCs). The approach uses the peak frequency of the power spectrum and the corresponding phase angle obtained by performing Fourier transform on the measured angular distribution of scattered light to determine these parameters. Results on the measurement of two important clinical parameters, the mean cell volume and mean cell hemoglobin concentration of a collection of RBCs, are presented.

  19. Abdominal varices mimicking an acute gastrointestinal hemorrhage during technetium-99m red blood cell scintigraphy

    SciTech Connect

    Moreno, A.J.; Byrd, B.F.; Berger, D.E.; Turnbull, G.L.

    1985-04-01

    Abdominal varices consisting of a caput medusae and dilated mesenteric veins resulted in pooling of Tc-99m tagged red blood cells (RBC) within these dilated vessels in a 57-year-old man with severe Laennec's cirrhosis. The atypical radiotracer localization within the abdomen mimicked an acute gastrointestinal hemorrhage. Clinical suspicion and careful evaluation of scintigraphic gastrointestinal bleeding studies will avoid false-positive interpretations.

  20. Haemoglobin-Triton X-100 conjugate as model system for red blood cell lysis

    NASA Astrophysics Data System (ADS)

    Pop, Simona-Florentina; Ion, Rodica-Mariana; Doncea, Sanda

    2010-11-01

    The action of detergents is thought to be connected primarily with micelle formation. However, detergent monomers can also affect biological systems. It was found that human red blood cells can be disintegrated with Triton X-100 non-ionic detergent at a concentration of 0.007%, lower than the critical micellar concentration (CMC). The lytic membrane of non-ionic detergent Triton X-100 (as a model), and its ability to lyse red blood cells in vitro used as an indicator of conjugate conformation at different pHs. The time dependent release of hemoglobin (Hb) and potassium from red blood cells was detected at 37 °C and both were sigmoid in character. Although Triton X-100 was highly lytic at pH 5.5, 7.4 and 8.0, the conjugate only show a lysis concentration-dependent of red blood cell at pH 5.5. Triton X-100 causes the Hb to aggregate, a condition that can be simulated when this non-ionic surfactant is incubated with Hb in vitro. The determination of Triton-X was done by HPLC, in accordance to characterize the surfactant. The increased stability in micellar medium can be attributed to deep penetration with the polar group -OH oriented towarded to the micelle surface. Thermal stability of hemoglobin has been investigated in order to evaluate the nature of thermal behavior of this compound. We studied the effects of surfactant Triton -X on the rate constants for the destroying of hemoglobin.

  1. The effect of osmotic pressure of aqueous PEG solutions on red blood cells.

    PubMed

    Herrmann, A; Arnold, K; Pratsch, L

    1985-08-01

    A drastic increase of the intracellular microviscosity of red blood cells in the presence of polyethylene glycol (PEG) was established by electron spin resonance using the small spin label molecule 2,2,6,6-tetramethyl-piperidine-N-oxyl-4-one (TEMPONE). The effective osmotic pressure of PEG solutions stressing the cells was estimated by comparison with those cytoplasmic rotational correlation times of TEMPONE measured in NaCl or sucrose containing media of known osmotic pressure. PMID:2998502

  2. Detection of Plasmodium falciparum-infected red blood cells by optical stretching

    NASA Astrophysics Data System (ADS)

    Mauritz, Jakob M. A.; Tiffert, Teresa; Seear, Rachel; Lautenschläger, Franziska; Esposito, Alessandro; Lew, Virgilio L.; Guck, Jochen; Kaminski, Clemens F.

    2010-05-01

    We present the application of a microfluidic optical cell stretcher to measure the elasticity of malaria-infected red blood cells. The measurements confirm an increase in host cell rigidity during the maturation of the parasite Plasmodium falciparum. The device combines the selectivity and sensitivity of single-cell elasticity measurements with a throughput that is higher than conventional single-cell techniques. The method has potential to detect early stages of infection with excellent sensitivity and high speed.

  3. Equilibrium physics breakdown reveals the active nature of red blood cell flickering

    NASA Astrophysics Data System (ADS)

    Turlier, Herve; Fedosov, Dmitry; Auth, Thorsten; Gov, Nir S.; Sykes, Cecile; Joanny, Jean-Francois; Gompper, Gerhard; Betz, Timo

    2015-03-01

    Red blood cell membrane flickering stimulated an abundant biological, biophysical and biochemical literature over the past 50 years. While the phenomenon has been interpreted as thermal fluctuations of the cell membrane, recent results suggest the involvement of metabolic processes. However, to date there is no direct and conclusive evidence that an active force drives membrane flickering. By comparing membrane undulations and active microrheology measurements on single human erythrocytes, we show that flickering is partly driven by an active metabolic process, as it does not satisfy the equilibrium fluctuation-dissipation relation on timescales slower than 100ms. Analytical and numerical models of the red blood cell reproduce experimental results. The analytical model assumes that membrane activity results from reversible binding of the elastic spectrin network to the lipid bilayer and predicts active fluctuations to increase with local curvature and extensional prestress in the cytoskeleton. Our mean-field calculation shows that the strength and kinetics of the binding activity regulates thereupon both passive and active mechanical properties of the red blood cell. Numerical simulations explore other possible origins of active forces on the membrane and predict coherent timescales for the molecular underlying metabolic processes.

  4. Multiplexed fluidic plunger mechanism for the measurement of red blood cell deformability.

    PubMed

    Myrand-Lapierre, Marie-Eve; Deng, Xiaoyan; Ang, Richard R; Matthews, Kerryn; Santoso, Aline T; Ma, Hongshen

    2015-01-01

    The extraordinary deformability of red blood cells gives them the ability to repeatedly transit through the microvasculature of the human body. The loss of this capability is part of the pathology of a wide range of diseases including malaria, hemoglobinopathies, and micronutrient deficiencies. We report on a technique for multiplexed measurements of the pressure required to deform individual red blood cell through micrometer-scale constrictions. This measurement is performed by first infusing single red blood cells into a parallel array of ~1.7 μm funnel-shaped constrictions. Next, a saw-tooth pressure waveform is applied across the constrictions to squeeze each cell through its constriction. The threshold deformation pressure is then determined by relating the pressure-time data with the video of the deformation process. Our key innovation is a self-compensating fluidic network that ensures identical pressures are applied to each cell regardless of its position, as well as the presence of cells in neighboring constrictions. These characteristics ensure the consistency of the measurement process and robustness against blockages of the constrictions by rigid cells and debris. We evaluate this technique using in vitro cultures of RBCs infected with P. falciparum, the parasite that causes malaria, to demonstrate the ability to profile the deformability signature of a heterogeneous sample. PMID:25325848

  5. Lisdexamfetamine prodrug activation by peptidase-mediated hydrolysis in the cytosol of red blood cells.

    PubMed

    Sharman, Johannah; Pennick, Michael

    2014-01-01

    Lisdexamfetamine dimesylate (LDX) is approved as a once-daily treatment for attention-deficit/hyperactivity disorder in children, adolescents, and adults in some countries. LDX is a prodrug comprising d-amphetamine covalently linked to l-lysine via a peptide bond. Following oral administration, LDX is rapidly taken up from the small intestine by active carrier-mediated transport, probably via peptide transporter 1. Enzymatic hydrolysis of the peptide bond to release d-amphetamine has previously been shown to occur in human red blood cells but not in several other tissues. Here, we report that LDX hydrolytic activity resides in human red blood cell lysate and cytosolic extract but not in the membrane fraction. Among several inhibitors tested, a protease inhibitor cocktail, bestatin, and ethylenediaminetetra-acetic acid each potently inhibited d-amphetamine production from LDX in cytosolic extract. These results suggest that an aminopeptidase is responsible for hydrolytic cleavage of the LDX peptide bond, although purified recombinant aminopeptidase B was not able to release d-amphetamine from LDX in vitro. The demonstration that aminopeptidase-like activity in red blood cell cytosol is responsible for the hydrolysis of LDX extends our understanding of the smooth and consistent systemic delivery of d-amphetamine by LDX and the long daily duration of efficacy of the drug in relieving the symptoms of attention-deficit/hyperactivity disorder. PMID:25489246

  6. Appropriateness of allogeneic red blood cell transfusion: the international consensus conference on transfusion outcomes.

    PubMed

    Shander, Aryeh; Fink, Arlene; Javidroozi, Mazyar; Erhard, Jochen; Farmer, Shannon L; Corwin, Howard; Goodnough, Lawrence Tim; Hofmann, Axel; Isbister, James; Ozawa, Sherri; Spahn, Donat R

    2011-07-01

    An international multidisciplinary panel of 15 experts reviewed 494 published articles and used the RAND/UCLA Appropriateness Method to determine the appropriateness of allogeneic red blood cell (RBC) transfusion based on its expected impact on outcomes of stable nonbleeding patients in 450 typical inpatient medical, surgical, or trauma scenarios. Panelists rated allogeneic RBC transfusion as appropriate in 53 of the scenarios (11.8%), inappropriate in 267 (59.3%), and uncertain in 130 (28.9%). Red blood cell transfusion was most often rated appropriate (81%) in scenarios featuring patients with hemoglobin (Hb) level 7.9 g/dL or less, associated comorbidities, and age older than 65 years. Red blood cell transfusion was rated inappropriate in all scenarios featuring patients with Hb level 10 g/dL or more and in 71.3% of scenarios featuring patients with Hb level 8 to 9.9 g/dL. Conversely, no scenario with patient's Hb level of 8 g/dL or more was rated as appropriate. Nearly one third of all scenarios were rated uncertain, indicating the need for more research. The observation that allogeneic RBC transfusions were rated as either inappropriate or uncertain in most scenarios in this study supports a more judicious transfusion strategy. In addition, the large number of scenarios in which RBC transfusions were rated as uncertain can serve as a road map to identify areas in need of further investigation. PMID:21498040

  7. Influence of Dietary Capsaicin on Redox Status in Red Blood Cells During Human Aging

    PubMed Central

    Kumar, Prabhanshu; Chand, Subhash; Chandra, Pranjal; Maurya, Pawan Kumar

    2015-01-01

    Purpose: Capsaicin (8-methyl-N-vanillyl-6-nonenamide) is a major pungent compound found in hot peppers of the plant genus Capsicum. In vitro effects of dietary capsaicin on redox status in red blood cells during human aging have been explored. Methods: Total antioxidant potential of capsaicin was evaluated using Ferric reducing ability of plasma (FRAP) assay. GSH was measured as per standard protocol. The in vitro effect of capsaicin was evaluated by incubation of the cells in the assay medium with 10-5M capsaicin (final concentration) for 60 min at 37°C. Results: Treatment with capsaicin (10-5M) caused a significant (p < 0.01) increase in GSH level in all age groups. Reduced glutathione (GSH) / Oxidized glutathione (GSSG) ratio measures the redox status of the red blood cell. Significant increase in GSH level due to capsaicin, shift the GSH/GSSG ratio, thus alters the redox status of the cell. Conclusion: The results conclusively prove the efficacy of the antioxidant property of capsaicin and its role in modulating the redox status of red blood cells. This evidence suggests that dietary factors that act as antioxidants to increase GSH level may contribute to a protective effect against age related diseases. This antioxidant effect may, in part, explain the high consumption of capsicum in certain regions of the world. PMID:26819932

  8. Lisdexamfetamine prodrug activation by peptidase-mediated hydrolysis in the cytosol of red blood cells

    PubMed Central

    Sharman, Johannah; Pennick, Michael

    2014-01-01

    Lisdexamfetamine dimesylate (LDX) is approved as a once-daily treatment for attention-deficit/hyperactivity disorder in children, adolescents, and adults in some countries. LDX is a prodrug comprising d-amphetamine covalently linked to l-lysine via a peptide bond. Following oral administration, LDX is rapidly taken up from the small intestine by active carrier-mediated transport, probably via peptide transporter 1. Enzymatic hydrolysis of the peptide bond to release d-amphetamine has previously been shown to occur in human red blood cells but not in several other tissues. Here, we report that LDX hydrolytic activity resides in human red blood cell lysate and cytosolic extract but not in the membrane fraction. Among several inhibitors tested, a protease inhibitor cocktail, bestatin, and ethylenediaminetetra-acetic acid each potently inhibited d-amphetamine production from LDX in cytosolic extract. These results suggest that an aminopeptidase is responsible for hydrolytic cleavage of the LDX peptide bond, although purified recombinant aminopeptidase B was not able to release d-amphetamine from LDX in vitro. The demonstration that aminopeptidase-like activity in red blood cell cytosol is responsible for the hydrolysis of LDX extends our understanding of the smooth and consistent systemic delivery of d-amphetamine by LDX and the long daily duration of efficacy of the drug in relieving the symptoms of attention-deficit/hyperactivity disorder. PMID:25489246

  9. Shear Stress induced Stretching of Red Blood Cells by Oscillating Bubbles within a Narrow Gap

    NASA Astrophysics Data System (ADS)

    Li, Fenfang; Mohammadzadeh, Milad; Ohl, Claus-Dieter; Claus-Dieter Ohl Team

    2013-11-01

    The flow pattern, especially the boundary layer caused by the expanding/contracting bubble in a narrow gap (15 μm) and the resultant stretching of red blood cells is investigated in this work. High speed recordings show that a red blood cell (biconcave shape, thickness of 1-2 μm) can be elongated to five times its original length by a laser-induced cavitation bubble within the narrow gap. However, flexible cancer cells in suspension (RKO, spherical shape, diameter of 10-15 μm) are hardly elongated under the same experimental condition. We hypothesize that the shear stress at the boundary layer is crucial for this elongation to occur. Therefore, in order to resolve the related fluid dynamics, we conducted numerical simulations using the finite element method (Fluent). The rapidly expanding/contracting vapor bubble is successfully modeled by employing viscosity and surface tension. The transient pressure inside the bubble and the velocity profile of the flow is obtained. We observe strong shear near the upper and lower boundary during the bubble oscillation. The flow fields are compared with analytical solutions to transient and pulsating flows in 2D. In the experiment the red blood cells sit within the lower boundary layer, thus are probably elongated by this strong shear flow. In contrast, the spherical cancer cells are of comparable size to the gap height so that they are lesser affected by this boundary layer flow.

  10. Effects of dietary triglycerides on rheological properties of human red blood cells (abstract).

    PubMed

    Cicha, I; Suzuki, Y; Tateishi, N; Maeda, N

    2004-01-01

    Atherogenic diets rich in saturated fat and cholesterol influence the blood viscosity and red blood cell (RBC) aggregability, the parameters associated with increased risk of circulatory disorders. However, little is known about the effect of triglycerides, which are the major dietary lipid form in humans, on blood rheology. Therefore, we studied the effects of postprandial plasma triglyceride levels on human RBC indices, hematological parameters, RBCs aggregation velocity and whole blood viscosity. For this purpose, whole blood was collected 2 hours after high-fat or low-fat meal. Proteins, triglycerides and cholesterol levels of plasma were analysed, and RBCs rouleaux formation rate was measured in 70% autologous plasma using a low-shear rheoscope. There were no significant differences in hematological parameters, RBC indices, whole blood viscosity, plasma protein and cholesterol content between high-fat and low-fat blood samples. However, a significant increase in rouleaux formation rate was observed in samples with high postprandial triglyceride levels, when compared with low-triglyceride samples. Plasma triglyceride levels correlated significantly with rouleaux formation rate. In conclusion, these results suggest that diet-dependent alterations of plasma triglyceride levels as well as possible changes in the cell membrane lipid composition lead to RBC hyperaggregability. PMID:15258358

  11. Automated microscopy system for detection and genetic characterization of fetal nucleated red blood cells on slides

    NASA Astrophysics Data System (ADS)

    Ravkin, Ilya; Temov, Vladimir

    1998-04-01

    The detection and genetic analysis of fetal cells in maternal blood will permit noninvasive prenatal screening for genetic defects. Applied Imaging has developed and is currently evaluating a system for semiautomatic detection of fetal nucleated red blood cells on slides and acquisition of their DNA probe FISH images. The specimens are blood smears from pregnant women (9 - 16 weeks gestation) enriched for nucleated red blood cells (NRBC). The cells are identified by using labeled monoclonal antibodies directed to different types of hemoglobin chains (gamma, epsilon); the nuclei are stained with DAPI. The Applied Imaging system has been implemented with both Olympus BX and Nikon Eclipse series microscopes which were equipped with transmission and fluorescence optics. The system includes the following motorized components: stage, focus, transmission, and fluorescence filter wheels. A video camera with light integration (COHU 4910) permits low light imaging. The software capabilities include scanning, relocation, autofocusing, feature extraction, facilities for operator review, and data analysis. Detection of fetal NRBCs is achieved by employing a combination of brightfield and fluorescence images of nuclear and cytoplasmic markers. The brightfield and fluorescence images are all obtained with a single multi-bandpass dichroic mirror. A Z-stack of DNA probe FISH images is acquired by moving focus and switching excitation filters. This stack is combined to produce an enhanced image for presentation and spot counting.

  12. Frequencies of red blood cell major blood group antigens and phenotypes in the Chinese Han population from Mainland China.

    PubMed

    Yu, Y; Ma, C; Sun, X; Guan, X; Zhang, X; Saldanha, J; Chen, L; Wang, D

    2016-08-01

    Alloantibodies directed to red blood cell (RBC) antigens play an important role in alloimmune-mediated haemolytic transfusion reactions and haemolytic disease of the foetus and newborn. The frequencies and phenotypes of RBC antigens are different in populations from different geographic areas and races. However, the data on major blood group antigens in the Chinese Han population from Mainland China are still very limited; thus, we aimed to investigate them in this study. A total of 1412 unrelated voluntary Chinese Han blood donors were randomly recruited. All donors were typed for blood group antigens: D, C, c, E, e, C(w) , Jk(a) , Jk(b) ,M, N, S, s, Le(a) , Le(b) , K, k. Kp(a) , Kp(b) , Fy(a) , Fy(b) , Lu(a) , Lu(b) , P1 and Di(a) using serological technology. Calculations of antigen and phenotype frequencies were expressed as percentages and for allele frequencies under the standard assumption of Hardy-Weinberg equilibrium. Amongst the Rh antigens, D was the most common (98.94%) followed by e (92.28%), C (88.81%), c (58.43%), E (50.78%) and C(w) (0.07%) with DCe/DCe (R1 R1 , 40.72%) being the most common phenotype. In the Kell blood group system, k was present in 100% of the donors and a rare phenotype, Kp (a+b+), was found in 0.28% of the donors. For the Kidd and Duffy blood group systems, Jk (a+b+) and Fy (a+b-) were the most common phenotypes (44.05% and 84.35%, respectively). In the MNS blood group system, M+N+S-s+ (45.54%) was the most common, whereas M+N-S-s- and M-N+S-s- were not found. The rare Lu (a-b-) and Lu (a+b+) phenotypes were identified in 0.43% and 1.13% of the donors, respectively. Le(a) and Le(b) were seen in 17.92% and 63.03% of donors, respectively. The frequency of Di(a) was 4.75%, which was higher than in the Chinese population in Taiwan region or the Caucasian and Black populations (P < 0.0001). This study systematically describes the frequencies of 24 blood group antigens in the Chinese Han population from Mainland China. The data can

  13. Emerging Role for Use of Liposomes in the Biopreservation of Red Blood Cells

    PubMed Central

    Holovati, Jelena L.; Acker, Jason P.

    2011-01-01

    Summary Biopreservation is the process of maintaining the integrity and functionality of cells held outside the native environment for extended storage times. The development of red blood cell (RBC) biopreservation techniques that maintain in vitro RBC viability and function represents the foundation of modern blood banking. The biopreservation of RBCs for clinical use can be categorized based on the techniques used to achieve biologic stability, including hypothermic storage and cryopreservation. This review will examine the emerging role of liposomes in the RBC biopreservation, including the incorporation of liposomes into RBC membranes as an effective approach for minimizing RBC hypothermic storage membrane lesion and use of liposomes as a permeabilization strategy for the intracellular accumulation of novel intracellular cryoprotectants. Integration of current biopreservation research with blood banking practices offers enormous potential for future improvements of safety and efficacy of RBC transfusion. PMID:21566711

  14. Poly(2-dimethylamino ethylmethacrylate)-based polymers to camouflage red blood cell antigens.

    PubMed

    Cerda-Cristerna, Bernardino Isaac; Cottin, Sophie; Flebus, Luca; Pozos-Guillén, Amaury; Flores, Héctor; Heinen, Ernst; Jolois, Olivier; Gérard, Christiane; Maggipinto, Gianni; Sevrin, Chantal; Grandfils, Christian

    2012-04-01

    Poly(2-dimethylamino-ethylmethacrylate) (PDMAEMA) is a cationic polymer when dissolved in a 7.4 pH fluid. Owing to its ionic nature, this polycation interacts with the negatively charged cell membrane surface of red blood cells (RBCs). The electrostatic self-assembly of PDMAEMA on RBCs membrane can be employed for inducing the formation of a polymeric shield camouflaging blood group antigens on RBCs as a valuable strategy for developing "universal RBCs" for blood transfusion. The purpose of this research was to evaluate the camouflaging ability of PDMAEMA homopolymers and PDMAEMA-co-poly(ethylene glycol) copolymers differing in molecular weight and architecture. Surprisingly, the PDMAEMAs caused a partially masking, no masking, and sensitization of the same RBCs population. The MW and architecture of the polymers as well as temperature of PDMAEMA-RBCs treatment influenced the results observed. Herein, the very particular reactivity of PDMAEMAs and RBCs is analyzed and discussed. PMID:22416913

  15. Correlation of Red Blood Cell Aggregate Size with Transmitted Light Intensity Distributions

    NASA Astrophysics Data System (ADS)

    Hitt, Darren L.

    1998-11-01

    Under sufficiently low shear rates, such as those encountered in the microcirculation, human red blood cells are known to form aggregate structures (`rouleaux'). These aggregates may range in size from a simple chain containing only a few cells to complex three-dimensional structures containing tens of cells. Previous studies have attempted to characterize the aggregate size by examining the spatial distribution of transmitted light intensity resulting from transillumination of the blood flow. For experiments performed in vitro and in vivo, spectral analysis of the transmitted light intensities has shown that the presence of aggregates in the flow can linked with an increase in the spectral power at small wavenumbers. The magnitudes of the affected wavenumbers correspond to structures considerably larger than individual cells. A precise numerical correlation, however, is difficult to establish. In this work, computer simulations of aggregating blood flow are used along with statistical considerations in an attempt to better correlate the observed spectral trends with actual aggregate size.

  16. Red cell antigen prevalence predicted by molecular testing in ethnic groups of South Texas blood donors.

    PubMed

    Aranda, Lorena I; Smith, Linda A; Jones, Scott; Beddard, Rachel

    2015-01-01

    Alloimmunization to red blood cell antigens is seen in patients receiving chronic blood transfusion. Knowing the prevalence of blood group antigens of the different ethnicities of South Texas donors can provide better management of rare blood inventory for patients in this geographical area. A total of 4369 blood donors were tested and analyzed for various antigens in the following blood group systems: ABO, Rh, Kell, Duffy, Kidd, MNS, Lutheran, Dombrock, Landsteiner-Wiener, Diego, Colton, and Scianna. Donors tested to be group 0 or A were serologically tested for the Rh (C, E, c, e) antigens. Those that tested as presumably R1R1, R2R2, or Ror were then genotyped. Donors constituted three major ethnicities: black (18.3%), Hispanic (36.3%), and Caucasian (41.1%); ethnicities comprised of Asian, American Indian, multiracial, and other accounted for the remaining donors (4.3%). The most likely common Rh phenotype for each ethnicity is as follows: black -Ror (44.4%), Hispanic -R1R1 (59.0%), and Caucasian -R1R1 (38.9%). The prevalence of Kell, Duffy, and Kidd blood group system antigens in black and Caucasian donors is comparable with published reports for the entire U.S. The black South Texas donor population had an 8.8 percent increase in prevalence of the Fy(a+b-) phenotype as compared with these published reports; the Hispanic South Texas donor population had a prevalence of 36.1 percent of the Fy(a+b-) phenotype. Regarding the Diego blood group system, the Hispanic donor population in South Texas had a prevalence of 93.5 percent for the Di(a-b+) phenotype as compared with published reports for the entire U.S. (>99.9%). The Hispanic population had a prevalence of 7.9 percent of donors testing as M-N+S-s+ as compared with 20.2 percent and 15.6 percent for black and Caucasian donors, respectively. This study helped us determine the prevalence of each of the blood group antigens in the South Texas donor population to establish and maintain adequate rare inventory of

  17. A model for oxygen-dependent backscattering spectroscopic contrast from single red blood cells (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Liu, Rongrong; Yi, Ji; Chen, Siyu; Zhang, Hao F.; Backman, Vadim

    2016-03-01

    The oxygen-dependent absorption of hemoglobin provides the fundamental contrast for all label-free techniques measuring blood oxygenation. When hemoglobin is packaged into red blood cells (RBCs), the structure of the cells creates light scattering which also depends on the absorption based on the Kramers-Kronig relationship. Thus a proper characterization of the optical behaviors of blood has been a key to any accurate measurement of blood oxygenation, particularly at the capillary level where RBCs are dispersed individually in contrast to a densely packed whole blood. Here we provided a theoretical model under Born Approximation to characterize the oxygen dependent backscattering spectroscopic contrast from single RBCs. Using this theoretical model, we conducted simulations on both oxygenated and deoxygenated single RBCs with different sizes for standard and possible deformed cell geometries in blood flow, all which suggested similar backscattering spectroscopic contrast and were confirmed by Mie Theory and experiments using visible Optical Coherence Tomography (visOCT). As long as the cell size satisfies Gaussian distribution with a coefficient variance (C.V.) large enough, there is clear absorption contrast between the backscattering spectra of oxygenated and deoxygenated single RBCs calculated by this model, so oxygen saturation can then be characterized. Thus, this theoretical model can be extended to extract absorption features of other scattering particles as long as they satisfy Born Approximation.

  18. Record And Analysis Of High-Speed Photomicrography On Rheology Of Red Blood Cells In Vivo

    NASA Astrophysics Data System (ADS)

    Jian, Zhang; Yuju, Lin; Jizong, Wu; Qiang, Wang; Guishan, Li; Ni, Liang

    1989-06-01

    Microcirculation is the basic functional unit of blood circulation in human body. The oxygen needed and the carbon dioxide discharged in human body were accomplished in the case of flow and deformation of red blood cells (RBC) in capillaries. The rheology of RBC performs an important function for maintaining normal blood irrigation and nutritional metabolism. Obviously, for blood irrigation, dynamic mechanism of RBC, blood cell microrheology, law of mivrocirculation and cause of disease, it has very important significance to study quantitatively the rheology of RBC in the capillaries of live animal. In recent years, Tianjin University, cooperating with the Institute of Hematology, used the method of high speed photomicrography to record the flow states of RBC in the capillaries of the hamster cheek pouch and the frog web. Some systems were assembled through the study of luminous energy transmission, illumination system and optical match. These systems included the microhigh-speed camera system, the microhighspeed video recorder system and the microhighspeed camera system combining with an image enhancement tube. Some useful results were obtained by the photography of the flow states of RBC, film analysis and data processing. These results provided the beneficial data for the dynamic mechanism that RBC were deformed by the different blood flow field.

  19. What is your diagnosis? Blood smear from an injured red-tailed hawk.

    PubMed

    Johns, Jennifer L; Luff, Jennifer A; Shooshtari, Mahrokh P; Zehnder, Ashley M; Borjesson, Dori L

    2009-06-01

    An injured juvenile red-tailed hawk (Buteo jamaicensis) was evaluated at the Veterinary Medical Teaching Hospital at the University of California, Davis. The hawk was quiet, alert, and emaciated, and had a closed comminuted, mid-diaphyseal ulnar fracture. CBC results included heterophilia with a left shift, monocytosis, and increased plasma fibrinogen concentration. The blood smear included rare heterophils containing small, dark blue inclusions approximately 1-2 mum in diameter that ranged from round to coccobacillary in shape and formed variably shaped aggregates; the morphology of the inclusions was suspicious for Chlamydophila or Ehrlichia spp. pathogens. The hawk died, and histopathologic examination of tissues obtained at necropsy found severe multifocal histiocytic and heterophilic splenitis in addition to chronic hepatitis, myocarditis and epicarditis, meningoencephalitis, and airsacculitis. Using immunohistochemistry the presence of Chlamydia/Chlamydophila spp. antigen within multiple tissues was confirmed. Chlamydophila psittaci DNA was demonstrated in whole blood and fresh splenic tissue via real-time PCR. Direct fluorescent antibody staining of air-dried blood smears was positive in rare leukocytes for Chlamydia/Chlamydophila spp. antigen, and immunocytochemical staining of blood smears for Chlamydia/Chlamydophila spp. antigen was focally positive in rare heterophils. These findings may represent the first reported diagnosis of natural avian C. psittaci infection by visualization of organisms in peripheral blood heterophils. Immunocytochemical evaluation of blood smears was valuable in confirming the diagnosis and may be a useful antemortem test to discriminate between bacteria and other inclusions within heterophils. PMID:19228359

  20. Computational Investigation on the Photoacoustics of Malaria Infected Red Blood Cells

    PubMed Central

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

    2012-01-01

    A computer simulation study on the possibility of using photoacoustic (PA) technique to differentiate intraerythrocytic stages of malarial parasite is reported. This parasite during its development substantially converts hemoglobin into hemozoin. This conversion is expected to alter the cellular absorption leading to changes in the PA emission of a red blood cell (RBC) at certain incident optical wavelengths. The PA signals from blood samples corresponding to ring, trophozoite and schizont stages were computed and compared with that of normal blood. A Monte Carlo algorithm was implemented generating random locations of RBCs in 3D to simulate blood samples. The average PA amplitude for wide bandwidth signals decreases for 434 nm incident radiation, but increases for 700 nm as the parasite matures. The spectral power at 7.5 MHz for the blood sample at the schizont stage compared to the normal blood is nearly reduced by 6 dB and enhanced by 22 dB at those incident wavelengths, respectively. Bandlimited signals for transducers of 15 and 50 MHz center frequencies were studied and found to exhibit similar characteristics. The presence of hemozoin inside the cells was examined and an excellent estimation was made. The simulation results suggest that intraerythrocytic stages of malarial parasite may be assessed using the PA technique. PMID:23272166

  1. Risk Factors for Alloimmunisation after red blood Cell Transfusions (R-FACT): a case cohort study

    PubMed Central

    Zwaginga, Jaap Jan; van der Bom, J G

    2012-01-01

    Introduction Individuals exposed to red blood cell alloantigens through transfusion, pregnancy or transplantation may produce antibodies against the alloantigens. Alloantibodies can pose serious clinical problems such as delayed haemolytic reactions and logistic problems, for example, to obtain timely and properly matched transfusion blood for patients in which new alloantibodies are detected. Objective The authors hypothesise that the particular clinical conditions (eg, used medication, concomitant infection, cellular immunity) during which transfusions are given may contribute to the risk of immunisation. The aim of this research was to examine the association between clinical, environmental and genetic characteristics of the recipient of erythrocyte transfusions and the risk against erythrocyte alloimmunisation during that transfusion episode. Methods and analysis Study design Incident case–cohort study. Setting Secondary care, nationwide study (within the Netherlands) including seven hospitals, from January 2005 to December 2011. Study population Consecutive red cell transfused patients at the study centres. Inclusion The study cohort comprises of consecutive red blood cell transfused patients at the study centre. Exclusion Patients with transfusions before the study period and/or pre-existing alloantibodies.Cases defined as first time alloantibody formers; Controls defined as transfused individuals matched (on number of transfusions) to cases and have not formed an alloantibody. Statistical analysis Logistic regression models will be used to assess the association between the risk to develop antibodies and potential risk factors, adjusted for other risk factors. Ethics and dissemination Approval at each local ethics regulatory committee will be obtained. Data will be coded for privacy reasons. Patients will be sent a letter and an information brochure explaining the purpose of the study. A consent form in presence of the study coordinator will be signed

  2. Early diagnosis of diabetic vascular complications: impairment of red blood cell deformability

    NASA Astrophysics Data System (ADS)

    Shin, Sehyun; Ku, Yunhee; Park, Cheol-Woo; Suh, Jang-Soo

    2006-02-01

    Reduced deformability of red blood cells (RBCs) may play an important role on the pathogenesis of chronic vascular complications of diabetes mellitus. However, available techniques for measuring RBC deformability often require washing process after each measurement, which is not optimal for day-to-day clinical use at point of care. The objectives of the present study are to develop a device and to delineate the correlation of impaired RBC deformability with diabetic nephropathy. We developed a disposable ektacytometry to measure RBC deformability, which adopted a laser diffraction technique and slit rheometry. The essential features of this design are its simplicity (ease of operation and no moving parts) and a disposable element which is in contact with the blood sample. We studied adult diabetic patients divided into three groups according to diabetic complications. Group I comprised 57 diabetic patients with normal renal function. Group II comprised 26 diabetic patients with chronic renal failure (CRF). Group III consisted of 30 diabetic subjects with end-stage renal disease (ESRD) on hemodialysis. According to the renal function for the diabetic groups, matched non-diabetic groups were served as control. We found substantially impaired red blood cell deformability in those with normal renal function (group I) compared to non-diabetic control (P = 0.0005). As renal function decreases, an increased impairment in RBC deformability was found. Diabetic patients with chronic renal failure (group II) when compared to non-diabetic controls (CRF) had an apparently greater impairment in RBC deformability (P = 0.07). The non-diabetic cohort (CRF), on the other hand, manifested significant impairment in red blood cell deformability compared to healthy control (P = 0.0001). The newly developed slit ektacytometer can measure the RBC deformability with ease and accuracy. In addition, progressive impairment in cell deformability is associated with renal function loss in all

  3. Alloimmunization screening after transfusion of red blood cells in a prospective study

    PubMed Central

    Alves, Vitor Mendonça; Martins, Paulo Roberto Juliano; Soares, Sheila; Araújo, Gislene; Schmidt, Luciana Cayres; Costa, Sidneia Sanches de Menezes; Langhi, Dante Mário; Moraes-Souza, Helio

    2012-01-01

    Background Several irregular red blood cell alloantibodies, produced by alloimmunization of antigens in transfusions or pregnancies, have clinical importance because they cause hemolysis in the fetus and newborn and in transfused patients. Objective a prospective analysis of patients treated by the surgical and clinical emergency services of Hospital de Clínicas of the Universidade Federal do Triângulo Mineiro (HC/UFTM), Brazil was performed to correlate alloimmunization to clinical and epidemiological data. Methods Blood samples of 143 patients with initial negative antibody screening were collected at intervals for up to 15 months after the transfusion of packed red blood cells. Samples were submitted to irregular antibody testing and, when positive, to the identification and serial titration of alloantibodies. The Fisher Exact test and Odds Ratio were employed to compare proportions. Results Fifteen (10.49%) patients produced antibodies within six months of transfusion. However, for 60% of these individuals, the titers decreased and disappeared by 15 months after transfusion. Anti-K antibodies and alloantibodies against antigens of the Rh system were the most common; the highest titer was 1:32 (anti-K). There was an evident correlation with the number of transfusions. Conclusions Given the high incidence of clinically important red blood cell alloantibodies in patients transfused in surgical and clinical emergency services, we suggest that phenotyping and pre-transfusion compatibilization for C, c, E, e (Rh system) and K (Kell system) antigens should be extended to all patients with programmed surgeries or acute clinical events that do not need emergency transfusions. PMID:23049421

  4. Association of haematocrit and red blood cell transfusion with outcomes in infants with shunt-dependent pulmonary blood flow and univentricular physiology

    PubMed Central

    Dasgupta, Rahul; Parsons, Andrew; McClelland, Sarenthia; Morgan, Elizabeth; Robertson, Michael J.; Noel, Tommy R.; Schmitz, Michael L.; Rettiganti, Mallikarjuna; Gupta, Punkaj

    2015-01-01

    Background The aim of this study was to investigate the association between red blood cell (RBC) transfusion and haematocrit values with outcomes in infants with univentricular physiology undergoing surgery for a modified Blalock-Taussig shunt. Material and methods This study included infants ≤ 2 months of age who underwent modified Blalock-Taussig shunt surgery at the Arkansas Children’s Hospital (2006–2012). Infants undergoing a Norwood operation or Damus-Kaye-Stansel operation with modified Blalock-Taussig shunt were excluded. Demographics, pre-operative, operative, daily laboratory data, and post-operative variables were collected. We studied the association between haematocrit and blood transfusion with a composite clinical outcome. Multivariable logistic regression models were fitted to study the probability of study outcomes as a function of haematocrit values and RBC transfusions after operation. Results Seventy-three patients qualified for inclusion. All study patients received blood transfusion within the first 48 hours after heart surgery. The median haematocrit was 44.3 (interquartile range [IQR] 42.5–46.2), and the median volume of RBC transfused was 28 mL/kg (IQR, 10–125) in the first 14 days after surgery. The overall in-hospital mortality rate was 13.6% (10 patients). A multivariable analysis adjusted for risk factors, including weight, prematurity, cardiopulmonary bypass and postoperative need for nitric oxide and dialysis, revealed no association between haematocrit values and RBC transfusion with the composite clinical outcome. Discussion We did not find an association between higher haematocrit values and increasing RBC transfusions with improved outcomes in infants with shunt-dependent pulmonary blood flow and univentricular physiology. The power of our study was small, which prevents any strong statement on this lack of association. Future multi-centre, randomised controlled trials are needed to investigate this topic in further

  5. Red blood cell complement receptor one level varies with Knops blood group, α+thalassaemia and age among Kenyan children

    PubMed Central

    Opi, D H; Uyoga, S; Orori, E N; Williams, T N; Rowe, J A

    2016-01-01

    Both the invasion of red blood cells (RBCs) by Plasmodium falciparum parasites and the sequestration of parasite-infected RBCs in the microvasculature are mediated in part by complement receptor one (CR1). RBC surface CR1 level can vary between individuals by more than 20-fold and may be associated with the risk of severe malaria. The factors that influence RBC CR1 level variation are poorly understood, particularly in African populations. We studied 3535 child residents of a malaria-endemic region of coastal Kenya and report, for the first time, that the CR1 Knops blood group alleles Sl2 and McCb, and homozygous HbSS are positively associated with RBC CR1 level. Sickle cell trait and ABO blood group did not influence RBC CR1 level. We also confirm the previous observation that α+thalassaemia is associated with reduced RBC CR1 level, possibly due to small RBC volume, and that age-related changes in RBC CR1 expression occur throughout childhood. RBC CR1 level in malaria-endemic African populations is a complex phenotype influenced by multiple factors that should be taken into account in the design and interpretation of future studies on CR1 and malaria susceptibility. PMID:26844958

  6. Red Blood Cell Membrane as a Biomimetic Nanocoating for Prolonged Circulation Time and Reduced Accelerated Blood Clearance.

    PubMed

    Rao, Lang; Bu, Lin-Lin; Xu, Jun-Hua; Cai, Bo; Yu, Guang-Tao; Yu, Xiaolei; He, Zhaobo; Huang, Qinqin; Li, Andrew; Guo, Shi-Shang; Zhang, Wen-Feng; Liu, Wei; Sun, Zhi-Jun; Wang, Hao; Wang, Tza-Huei; Zhao, Xing-Zhong

    2015-12-01

    For decades, poly(ethylene glycol) (PEG) has been widely incorporated into nanoparticles for evading immune clearance and improving the systematic circulation time. However, recent studies have reported a phenomenon known as "accelerated blood clearance (ABC)" where a second dose of PEGylated nanomaterials is rapidly cleared when given several days after the first dose. Herein, we demonstrate that natural red blood cell (RBC) membrane is a superior alternative to PEG. Biomimetic RBC membrane-coated Fe(3)O(4) nanoparticles (Fe(3)O(4) @RBC NPs) rely on CD47, which is a "don't eat me" marker on the RBC surface, to escape immune clearance through interactions with the signal regulatory protein-alpha (SIRP-α) receptor. Fe(3)O(4) @RBC NPs exhibit extended circulation time and show little change between the first and second doses, with no ABC suffered. In addition, the administration of Fe(3)O(4) @RBC NPs does not elicit immune responses on neither the cellular level (myeloid-derived suppressor cells (MDSCs)) nor the humoral level (immunoglobulin M and G (IgM and IgG)). Finally, the in vivo toxicity of these cell membrane-camouflaged nanoparticles is systematically investigated by blood biochemistry, hematology testing, and histology analysis. These findings are significant advancements toward solving the long-existing clinical challenges of developing biomaterials that are able to resist both immune response and rapid clearance. PMID:26488923

  7. Hyperemic peripheral red marrow in a patient with sickle cell anemia demonstrated on Tc-99m labeled red blood cell venography

    SciTech Connect

    Heiden, R.A.; Locko, R.C.; Stent, T.R. )

    1991-03-01

    A 25-year-old gravid woman, homozygous for sickle cell anemia, with a history of recent deep venous thrombosis, was examined using Tc-99m labeled red blood cell venography for recurrent thrombosis. Although negative for thrombus, the study presented an unusual incidental finding: the patient's peripheral bone marrow was hyperemic in a distribution consistent with peripheral red bone marrow expansion. Such a pattern has not been documented before using this technique. This report supports other literature that has demonstrated hyperemia of peripheral red bone marrow in other hemolytic anemias. This finding may ultimately define an additional role of scintigraphy in assessing the pathophysiologic status of the sickle cell patient.

  8. Ion channels in human red blood cell membrane: actors or relics?

    PubMed

    Thomas, Serge L Y; Bouyer, Guillaume; Cueff, Anne; Egée, Stéphane; Glogowska, Edyta; Ollivaux, Céline

    2011-04-15

    During the past three decades, electrophysiological studies revealed that human red blood cell membrane is endowed with a large variety of ion channels. The physiological role of these channels, if any, remains unclear; they do not participate in red cell homeostasis which is rather based on the almost total absence of cationic permeability and minute anionic conductance. They seem to be inactive in the "resting cell." However, when activated experimentally, ion channels can lead to a very high single cell conductance and potentially induce disorders, with the major risks of fast dehydration and dissipation of gradients. Could there be physiological conditions under which the red cell needs to activate these high conductances, or are ion channels relics of a function lost in anucleated cells? It has been demonstrated that they play a key role in diseases such as sickle cell anemia or malaria. This short overview of ion channels identified to-date in the human red cell membrane is an attempt to propose a dynamic role for these channels in circulating cells in health and disease. PMID:21429775

  9. Use of red blood cell membranes to evaluate the antioxidant potential of plant extracts.

    PubMed

    Cavallini, Gabriella; Dachà, Marina; Potenza, Lucia; Ranieri, Annamaria; Scattino, Claudia; Castagna, Antonella; Bergamini, Ettore

    2014-06-01

    Antioxidant phytochemicals in fruits and vegetables of a vegetarian diet may account for the reduced risk of aging and stress oxidative associated diseases. In this study, a simple, rapid and accurate new bioassay for the determination of the antioxidant activity of purified or crude plant extracts and thier interactions is described, based on the fluorimetric determination of thiobarbituric acid reactive substances (TBARS) released by UV-B radiated red blood cell (RBC) ghosts. Pure resveratrol, white and red wine and pomegranate juice (PJ) were used as antioxidant source to test the biological method. TBARS production is a function of radiation time, the number of RBC ghosts in the radiated sample and the loaded antioxidant. The antioxidant activity of resveratrol was detected at a submicromolar concentration range [0.02 μg/mL-0.1 μmol/L]. The activity of red wine was almost 10 times higher than that of white wine, and PJ juice had the highest activity. Submaximal protective effects of PJ and red wine were additive. PMID:24682659

  10. The effect of curvature on the undulation spectrum of Red Blood Cell membranes

    NASA Astrophysics Data System (ADS)

    Kuriabova, Tatiana; Henle, Mark L.; Levine, Alex J.

    2009-03-01

    The human red blood cell (RBC) membrane has a composite structure of a fluid lipid bilayer tethered to an elastic 2D spectrin network. The study of the mechanical properties of RBCs is crucial to our understanding of their ability withstand large amplitude deformations during their passage through the microvasculature. The linear mechanical response of this composite membrane can be measured by observing its undulatory dynamics in thermal equilibrium, i.e. microrheology. Previous models of these dynamics postulated an effective surface tension. In this talk, we show that surface tension is not necessary. Rather, the coupling of membrane bending to spectrin network compression by curvature can account for the observed dynamics. We use a simplified theoretical model to describe the undulatory dynamics of RBCs, measured experimentally by the Popescu group.ootnotetextG. Popescu et al. ``Imaging red blood cell dynamics by quantitative phase microscopy, Blood Cells, Molecules, and Diseases, (2008), in print'' Analyzing their data using our model, we observe dramatic changes in RBC membrane elasticity associated with cells' morphological transition from discocytes to echinocyte to spherocyte.

  11. Cerebral blood flow and red cell delivery in normal subjects and in multiple sclerosis

    SciTech Connect

    Swank, R.L.; Roth, J.G.; Woody, D.C. Jr.

    1983-01-01

    Regional cerebral blood flow (rCBF) was determined in 77 normal females and 53 normal males of different ages and in 26 men and 45 women with multiple sclerosis by the inhalation of radioactive Xe133 method. In the normal subjects the CBF was relatively high in the teens and fell, at first rapidly and then slowly in both sexes with age. During adult life the flow in females was significantly higher than in males. The delivery of packed red cells (RCD) was determined by multiplying the CBF by the percentage concentration of red cells (HCT). The RCD for both sexes was nearly the same. In the patients with multiple sclerosis there occurred a progressive generalized decrease in CBF and in RCD with age which was significantly greater than observed in normal subjects. The rate of decrease in CBF and RCD correlated directly with the rate of progress of the disease.

  12. Multispectral quantitative phase imaging of human red blood cells using inexpensive narrowband multicolor LEDs.

    PubMed

    Dubey, Vishesh; Singh, Gyanendra; Singh, Veena; Ahmad, Azeem; Mehta, Dalip Singh

    2016-04-01

    We report multispectral phase-shifting interference microscopy for quantitative phase imaging of human red blood cells (RBCs). A wide range of wavelengths are covered by means of using multiple color light emitting diodes (LEDs) with narrow spectral bandwidth ranging from violet to deep red color. The multicolor LED light source was designed and operated sequentially, which works as a multispectral scanning light source. Corresponding to each color LED source, five phase-shifted interferograms were recorded sequentially for the measurement of phase maps, as well as the refractive index of RBCs within the entire visible region. The proposed technique provides information about the effect of wavelengths on the morphology and refractive index of human RBCs. The system does not require expensive multiple color filters or any wavelength scanning mechanism along with broadband light source. PMID:27139652

  13. The role of the red blood cell in the transport of carbon disulfide.

    PubMed

    Lam, C W; DiStefano, V; Morken, D A

    1986-04-01

    When rats were exposed to 2 mg l-1 (approximately 640 ppm) of carbon disulfide (CS2) for 4 h, the concentration of free CS2 in the red blood cells (RBCs) approached a plateau within 2 h. Free CS2 in plasma reached a steady state concentration within 15 min of exposure. More than 90% of the free CS2 in blood was found in the RBCs regardless of the length of exposure. In vitro studies showed that about 90% of the free CS2 partitioned into the RBCs regardless of whether the CS2 was added first to the plasma or directly to the RBCs. Hence, it appears that the RBC is the major carrier of CS2 in blood. It was found that 98% of the free CS2 in red blood cell lysates was associated with hemoglobin. Free CS2 in RBCs was readily partitioned into olive oil (RBCs/oil = 1/6), less readily into the plasma (RBCs/plasma = 12/1), and only to a small extent into phosphate buffer (RBCs/buffer = 39/1). The extraction of free CS2-loaded RBCs into albumin solution increased with increasing albumin concentrations. CS2 can be extracted with buffer, protein solution, and oil, indicating that CS2 in RBCs can be transferred to the medium in which the RBCs contact. It is proposed that RBCs may also play an important role in the transport of CS2 from lung to tissues and vice versa. The possible role of RBCs in the transport of other organic solvents in the blood is also discussed. PMID:3700964

  14. [Structure of red blood cell and peripheral blood lymphocytes membranes in children--residents of contaminated areas in the remote period of Chernobyl].

    PubMed

    Stepanova, E I; Vdovenko, V Iu; Litvinets, O M

    2013-06-01

    We applied scanning electron microscope to study of surface architectonics of erythrocytes and lymphocytes peripheral blood in children born after the Chernobyl accident and living in conditions of chronic incorporation 137Cs. We found significant changes in surface structure membranes of red blood cells and peripheral blood lymphocytes in the basic childrens group compared with control one. The most striking changes were in children with levels incorporated 137Cs from 6845 to 16522 Bq. PMID:25095676

  15. Overweight explains the increased red blood cell aggregation in patients with obstructive sleep apnea.

    PubMed

    Sinnapah, Stéphane; Cadelis, Gilbert; Waltz, Xavier; Lamarre, Yann; Connes, Philippe

    2015-01-01

    Sleep apnea patients and obese subjects are overexposed to cardiovascular diseases. These two health conditions may be associated with hemorheological alterations which could increase the cardiovascular risk. The present study investigated the hemorheological characteristics in patients with overweight and/or sleep apnea to identify the main predictor of red blood cell (RBC) abnormalities in sleep apnea patients. Ninety-seven patients were subjected to one night sleep polygraphy to determine their sleep apnea status. Body mass index (BMI) and the apnea/hypopnea index (AHI) were determined for categorization of obesity and sleep apnea status. Blood was sampled for hematocrit, blood viscosity, RBC deformability, aggregation and disaggregation threshold measurements. BMI and AHI were positively associated and were both positively associated with RBC aggregation. Analyses of covariance and multiple regression analyses revealed that BMI was more predictive of RBC aggregation than AHI. No association of BMI classes and AHI classes with RBC deformability or blood viscosity was observed. This study shows that increased RBC aggregation in sleep apnea patients is caused by overweight. Therapies to improve blood rheology in sleep apnea patients, and therefore reduce the risk for cardiovascular disorders, should focus on weight-loss. PMID:23271197

  16. Preservation of 5300 year old red blood cells in the Iceman

    PubMed Central

    Janko, Marek; Stark, Robert W.; Zink, Albert

    2012-01-01

    Changes in elasticity and structures of red blood cells (RBCs) are important indicators of disease, and this makes them interesting for medical studies. In forensics, blood analyses represent a crucial part of crime scene investigations. For these reasons, the recovery and analysis of blood cells from ancient tissues is of major interest. In this study, we show that RBCs were preserved in Iceman tissue samples for more than 5000 years. The morphological and molecular composition of the blood corpuscle is verified by atomic force microscope and Raman spectroscopy measurements. The cell size and shape approximated those of healthy, dried, recent RBCs. Raman spectra of the ancient corpuscle revealed bands that are characteristic of haemoglobin. Additional vibrational modes typical for other proteinaceous fragments, possibly fibrin, suggested the formation of a blood clot. The band intensities, however, were approximately an order of magnitude weaker than those of recent RBCs. This fact points to a decrease in the RBC-specific metalloprotein haemoglobin and, thus, to a degradation of the cells. Together, the results show the preservation of RBCs in the 5000 year old mummy tissue and give the first insights into their degradation. PMID:22552923

  17. In-vitro stem cell derived red blood cells for transfusion: are we there yet?

    PubMed

    Kim, Hyun Ok

    2014-03-01

    To date, the use of red blood cells (RBCs) produced from stem cells in vitro has not proved practical for routine transfusion. However, the perpetual and widespread shortage of blood products, problems related to transfusion-transmitted infections, and new emerging pathogens elicit an increasing demand for artificial blood. Worldwide efforts to achieve the goal of RBC production through stem cell research have received vast attention; however, problems with large-scale production and cost effectiveness have yet to prove practical usefulness. Some progress has been made, though, as cord blood stem cells and embryonic stem cells have shown an ability to differentiate and proliferate, and induced pluripotent stem cells have been shown to be an unlimited source for RBC production. However, transfusion of stem cell-derived RBCs still presents a number of challenges to overcome. This paper will summarize an up to date account of research and advances in stem cell-derived RBCs, delineate our laboratory protocol in producing RBCs from cord blood, and introduce the technological developments and limitations to current RBC production practices. PMID:24532496

  18. Design of a microfluidic system for red blood cell aggregation investigation.

    PubMed

    Mehri, R; Mavriplis, C; Fenech, M

    2014-06-01

    The purpose of this paper is to design a microfluidic apparatus capable of providing controlled flow conditions suitable for red blood cell (RBC) aggregation analysis. The linear velocity engendered from the controlled flow provides constant shear rates used to qualitatively analyze RBC aggregates. The design of the apparatus is based on numerical and experimental work. The numerical work consists of 3D numerical simulations performed using a research computational fluid dynamics (CFD) solver, Nek5000, while the experiments are conducted using a microparticle image velocimetry system. A Newtonian model is tested numerically and experimentally, then blood is tested experimentally under several conditions (hematocrit, shear rate, and fluid suspension) to be compared to the simulation results. We find that using a velocity ratio of 4 between the two Newtonian fluids, the layer corresponding to blood expands to fill 35% of the channel thickness where the constant shear rate is achieved. For blood experiments, the velocity profile in the blood layer is approximately linear, resulting in the desired controlled conditions for the study of RBC aggregation under several flow scenarios. PMID:24700377

  19. In-Vitro Stem Cell Derived Red Blood Cells for Transfusion: Are We There Yet?

    PubMed Central

    2014-01-01

    To date, the use of red blood cells (RBCs) produced from stem cells in vitro has not proved practical for routine transfusion. However, the perpetual and widespread shortage of blood products, problems related to transfusion-transmitted infections, and new emerging pathogens elicit an increasing demand for artificial blood. Worldwide efforts to achieve the goal of RBC production through stem cell research have received vast attention; however, problems with large-scale production and cost effectiveness have yet to prove practical usefulness. Some progress has been made, though, as cord blood stem cells and embryonic stem cells have shown an ability to differentiate and proliferate, and induced pluripotent stem cells have been shown to be an unlimited source for RBC production. However, transfusion of stem cell-derived RBCs still presents a number of challenges to overcome. This paper will summarize an up to date account of research and advances in stem cell-derived RBCs, delineate our laboratory protocol in producing RBCs from cord blood, and introduce the technological developments and limitations to current RBC production practices. PMID:24532496

  20. Red blood cell coagulation induced by low-temperature plasma treatment.

    PubMed

    Miyamoto, Kenji; Ikehara, Sanae; Takei, Hikaru; Akimoto, Yoshihiro; Sakakita, Hajime; Ishikawa, Kenji; Ueda, Masashi; Ikeda, Jun-Ichiro; Yamagishi, Masahiro; Kim, Jaeho; Yamaguchi, Takashi; Nakanishi, Hayao; Shimizu, Tetsuji; Shimizu, Nobuyuki; Hori, Masaru; Ikehara, Yuzuru

    2016-09-01

    Low-temperature plasma (LTP) treatment promotes blood clot formation by stimulation of the both platelet aggregation and coagulation factors. However, the appearance of a membrane-like structure in clots after the treatment is controversial. Based on our previous report that demonstrated characteristics of the form of coagulation of serum proteins induced by LTP treatment, we sought to determine whether treatment with two plasma instruments, namely BPC-HP1 and PN-110/120TPG, formed clots only from red blood cells (RBCs). LTP treatment with each device formed clots from whole blood, whereas LTP treatment with BPC-HP1 formed clots in phosphate-buffered saline (PBS) containing 2 × 10(9)/mL RBCs. Light microscopic analysis results showed that hemolysis formed clots consisting of materials with membrane-like structures from both whole blood and PBS-suspended RBCs. Moreover, electron microscopic analysis results showed a monotonous material with high electron density in the formed clots, presenting a membrane-like structure. Hemolysis disappeared with the decrease in the current through the targets contacting with the plasma flare and clot formation ceased. Taken together, our results and those of earlier studies present two types of blood clot formation, namely presence or absence of hemolysis capability depending on the current through the targets. PMID:27033148

  1. Predicting red blood cell transfusion in hospitalized patients: role of hemoglobin level, comorbidities, and illness severity

    PubMed Central

    2014-01-01

    Background Randomized controlled trial evidence supports a restrictive strategy of red blood cell (RBC) transfusion, but significant variation in clinical transfusion practice persists. Patient characteristics other than hemoglobin levels may influence the decision to transfuse RBCs and explain some of this variation. Our objective was to evaluate the role of patient comorbidities and severity of illness in predicting inpatient red blood cell transfusion events. Methods We developed a predictive model of inpatient RBC transfusion using comprehensive electronic medical record (EMR) data from 21 hospitals over a four year period (2008-2011). Using a retrospective cohort study design, we modeled predictors of transfusion events within 24 hours of hospital admission and throughout the entire hospitalization. Model predictors included administrative data (age, sex, comorbid conditions, admission type, and admission diagnosis), admission hemoglobin, severity of illness, prior inpatient RBC transfusion, admission ward, and hospital. Results The study cohort included 275,874 patients who experienced 444,969 hospitalizations. The 24 hour and overall inpatient RBC transfusion rates were 7.2% and 13.9%, respectively. A predictive model for transfusion within 24 hours of hospital admission had a C-statistic of 0.928 and pseudo-R2 of 0.542; corresponding values for the model examining transfusion through the entire hospitalization were 0.872 and 0.437. Inclusion of the admission hemoglobin resulted in the greatest improvement in model performance relative to patient comorbidities and severity of illness. Conclusions Data from electronic medical records at the time of admission predicts with very high likelihood the incidence of red blood transfusion events in the first 24 hours and throughout hospitalization. Patient comorbidities and severity of illness on admission play a small role in predicting the likelihood of RBC transfusion relative to the admission hemoglobin. PMID

  2. The involvement of cation leaks in the storage lesion of red blood cells

    PubMed Central

    Flatt, Joanna F.; Bawazir, Waleed M.; Bruce, Lesley J.

    2014-01-01

    Stored blood components are a critical life-saving tool provided to patients by health services worldwide. Red cells may be stored for up to 42 days, allowing for efficient blood bank inventory management, but with prolonged storage comes an unwanted side-effect known as the “storage lesion”, which has been implicated in poorer patient outcomes. This lesion is comprised of a number of processes that are inter-dependent. Metabolic changes include a reduction in glycolysis and ATP production after the first week of storage. This leads to an accumulation of lactate and drop in pH. Longer term damage may be done by the consequent reduction in anti-oxidant enzymes, which contributes to protein and lipid oxidation via reactive oxygen species. The oxidative damage to the cytoskeleton and membrane is involved in increased vesiculation and loss of cation gradients across the membrane. The irreversible damage caused by extensive membrane loss via vesiculation alongside dehydration is likely to result in immediate splenic sequestration of these dense, spherocytic cells. Although often overlooked in the literature, the loss of the cation gradient in stored cells will be considered in more depth in this review as well as the possible effects it may have on other elements of the storage lesion. It has now become clear that blood donors can exhibit quite large variations in the properties of their red cells, including microvesicle production and the rate of cation leak. The implications for the quality of stored red cells from such donors is discussed. PMID:24987374

  3. Tc-99m-labeled red blood cells for the measurement of red cell mass in newborn infants: concise communication

    SciTech Connect

    Linderkamp, O.; Betke, K.; Fendel, H.; Klemm, J.; Lorenzen, K.; Riegel, K.P.

    1980-07-01

    In vitro and in vivo investigations were performed to examine the binding of Tc-99m to neonatal red blood cells (RBC). Labeling efficiency was about 90%, and unbound Tc-99m less than 3% after one washing, in premature and full-term newborns and in children. Thus presence of high percentages of fetal hemoglobin (Hb F) did not influence the labeling of RBCs with Tc-99m. RBCs of 11 newborns were hemolysed and the distribution of Tc-99m on RBC components was analyzed. Although Hb F percentage averaged (60.0 +- 8.10)% (s.d.), only (11.9 +- 3.7)% of Tc-99m was bound by Hb F, whereas (45.0 +- 6.1)% was associated with Hb A. RBC membranes bound (13.7 +- 4.3)% and (29.3 +- 4.0)% were found unbound in hemolysates. These results indicate that Tc-99m preferentially binds to beta chains. In vivo equilibration of Tc-99m RBCs and of albumin labeled with Evans blue was investigated in five newborn infants. Tc-99m RBCs were stable in each case during the first hour after injection. Elution of Tc-99m from RBCs was (3.4 +- 1.5)% per h. Body-to-venous hematocrit ratio averaged 0.86 +- 0.03.

  4. Columnar deformation of human red blood cell by highly localized fiber optic Bessel beam stretcher

    PubMed Central

    Lee, Sungrae; Joo, Boram; Jeon, Pyo Jin; Im, Seongil; Oh, Kyunghwan

    2015-01-01

    A single human red blood cell was optically stretched along two counter-propagating fiber-optic Bessel-like beams in an integrated lab-on-a-chip structure. The beam enabled highly localized stretching of RBC, and it induced a nonlinear mechanical deformation to finally reach an irreversible columnar shape that has not been reported. We characterized and systematically quantified this optically induced mechanical deformation by the geometrical aspect ratio of stretched RBC and the irreversible stretching time. The proposed RBC mechanism can realize a versatile and compact opto-mechanical platform for optical diagnosis of biological substances in the single cell level. PMID:26601005

  5. Profiling individual human red blood cells using common-path diffraction optical tomography

    NASA Astrophysics Data System (ADS)

    Kim, Youngchan; Shim, Hyoeun; Kim, Kyoohyun; Park, Hyunjoo; Jang, Seongsoo; Park, Yongkeun

    2014-10-01

    Due to its strong correlation with the pathophysiology of many diseases, information about human red blood cells (RBCs) has a crucial function in hematology. Therefore, measuring and understanding the morphological, chemical, and mechanical properties of individual RBCs is a key to understanding the pathophysiology of a number of diseases in hematology, as well as to opening up new possibilities for diagnosing diseases in their early stages. In this study, we present the simultaneous and quantitative measurement of the morphological, chemical, and mechanical parameters of individual RBCs employing optical holographic microtomography. In addition, it is demonstrated that the correlation analyses of these RBC parameters provide unique information for distinguishing and understanding diseases.

  6. Characterizations of individual mouse red blood cells parasitized by Babesia microti using 3-D holographic microscopy

    PubMed Central

    Park, HyunJoo; Hong, Sung-Hee; Kim, Kyoohyun; Cho, Shin-Hyeong; Lee, Won-Ja; Kim, Youngchan; Lee, Sang-Eun; Park, YongKeun

    2015-01-01

    Babesia microti causes “emergency” human babesiosis. However, little is known about the alterations in B. microti invaded red blood cells (Bm-RBCs) at the individual cell level. Through quantitative phase imaging techniques based on laser interferometry, we present the simultaneous measurements of structural, chemical, and mechanical modifications in individual mouse Bm-RBCs. 3-D refractive index maps of individual RBCs and in situ parasite vacuoles are imaged, from which total contents and concentration of dry mass are also precisely quantified. In addition, we examine the dynamic membrane fluctuation of Bm-RBCs, which provide information on cell membrane deformability. PMID:26039793

  7. Popliteal cysts and deep venous thrombosis: Tc-99m red blood cell venography

    SciTech Connect

    Littlejohn, G.O.; Brand, C.A.; Ada, A.; Wong, C.

    1985-04-01

    Thirty-four patients who clinically were suspected of having deep venous thrombosis (DVT) underwent Tc-99m red blood cell (RBC) venography followed by contrast venography. The sensitivity (88%) and specificity (94%) of Tc-99m RBC venography of DVT confirmed findings of previous studies. Twenty-four patients who had proved popliteal cysts and swollen calves also were examined using Tc-99m RBC venography. Large cysts showed lack of DVT features, photon deficient cold areas in the popliteal fossa, and diversion of venous flow around the photon deficient area. These features were seen in 25% of the study population (six patients), and assisted in the distinction between the two conditions.

  8. Simplified variant of an optical chip to evaluate aggregation of red blood cells

    NASA Astrophysics Data System (ADS)

    Toderi, Martín. A.; Riquelme, Bibiana D.; Castellini, Horacio V.

    2015-06-01

    Traditional techniques to evaluate the aggregation of red blood cells by optical methods require large sample volume and provide parameters that vary significantly from one method to another. A simplified variant of a chip system previously developed by Shin et al. (2009)1 based on light transmission for measuring erythrocyte aggregation is presented. Through a detailed analysis of intensity versus time curves, relevant information about erythrocyte aggregation and its variables is obtained. Parameters that provide more accuracy for the diagnosis of patients in order to have an immediate application in Clinical Medicine are proposed.

  9. Highly Sensitive Detection of Red Blood Cell Aggregation with Ultrasonic Peak Frequency

    NASA Astrophysics Data System (ADS)

    Sato, Takayuki; Tojo, Hiroyuki; Watanabe, Yasuaki

    2013-07-01

    A novel technique of detecting the peak frequency of an ultrasonic reflection spectrum was proposed, with the aim of enhancing the sensitivity and accuracy of estimating the aggregation size of red blood cells (RBCs). Peak frequencies for stagnant and running suspensions prepared with monodisperse particles of graphite and acryl that were used to mimic aggregated RBCs were acquired. As a result, the relationships between particle diameter and peak frequency, which were independent of the material of the particles and flow rate, were obtained. For bidisperse samples, i.e., mixtures of two different sizes of particle samples, quantitative relationships corresponding to changes in the mixing ratio were observed.

  10. Metabolism of red blood cells in chronic renal failure. I. Glycolytic enzyme levels.

    PubMed

    Rodríguez-Commes, J L; Tabernero, J M; Martin-Vasallo, P; De Castro, S; Battaner, E

    1979-01-01

    This paper starts a series on red blood cell (RBC) metabolism in patients with chronic renal failure (CRF). The glycolytic enzyme levels and in vitro half-lives of these patients' RBCs were determined. A number of enzymes (hexokinase, glucose-6-phosphate isomerase, fructose-6-phosphate kinase, aldolase, glyceraldehyde-3-phosphate dehydrogenase and lactate dehydrogenase) showed higher activities than in normal control RBCs. Other enzyme activities were normal. These results were discussed and several possible mechanisms considered. We favour the point of view of a shortened life span of the RBCs in CRF, making the most unstable enzymes of the glycolytic sequence appear increase as compared with normal controls. PMID:226898

  11. A case of metastatic malignancy masquerading as a hepatic hemangioma on labeled red blood cell scintigraphy.

    PubMed

    Farlow, D C; Little, J M; Gruenewald, S M; Antico, V F; O'Neill, P

    1993-07-01

    A 36-yr-old woman with a past history of gastric neuro-endocrine carcinoma (carcinoid tumor) underwent 99mTc-red blood cell (RBC) scintigraphy for evaluation of a 2-cm echogenic liver mass demonstrated on ultrasound. Scan findings were typical of a cavernous hemangioma. On follow-up, however, there was progressive lesion enlargement; histopathology of the resected mass revealed neuro-endocrine carcinoma. This case report, one of the few examples of a false-positive 99mTc-RBC scan, highlights the need for cautious evaluation of focal liver masses, even when there are typical scintigraphic features of cavernous hemangioma. PMID:8315498

  12. The response of the metabolic network of the red blood cell to pyruvate kinase deficiency.

    PubMed

    Sun, Xiaoliang; Lu, Zuhong

    2005-01-01

    The response of the metabolic network of human red blood cell is investigated using the E-Cell simulation system when pyruvate kinase (PK) is deficient. The results that several downstream metabolites of the glycolysis pathway accumulate are in a good agreement with experimental data reported in literatures. This accumulation results in the reaction that phosphoglycerate kinase (PGK) catalyzes reversing its direction. Mathematical analysis to the simulation results shows that the PGK-catalyzing reaction reversing its direction happens simultaneously with an abrupt change of the second derivative of the ATP quantity. PMID:17282332

  13. Zinc and magnesium concentrations in plasma and red blood cells in patients on digitalis medication

    SciTech Connect

    Zumkley, H.; Bertram, H.P.; Vetter, H.; Zidek, W.; Wessels, F.

    1981-06-01

    Determinations of zinc, sodium, potassium and magnesium in plasma and red blood cells (RBC) were performed in 31 controls and 63 patients treated with digitalis. In digitalized patients Na and Zn concentrations in RBC were significantly increased, whereas the intraerythrocyte Mg concentration was only slightly elevated. Plasma concentrations of all investigated electrolytes as well as of Zn remained within the normal range. There was a close relationship between the increase of Na and Zn content in RBC indicating alterations in transmembrane transport mechanisms induced by digitalis therapy.

  14. Kinetics of red blood cell aggregation: an example of geometric polymerization

    SciTech Connect

    Perelson, A.S.; Samsel, R.W.

    1984-04-02

    The kinetics of the process by which red blood cells aggregate into long cylindrical, and sometimes branched, structures called rouleaux is studied within the framework of both reversible and irreversible addition and condensation polymerization reactions. However, unlike usual polymer kinetics, here we take into account the geometry of the subunits and the geometry of the growing structure. Geometric factors such as the amount of reactive wall area influence the probability of branching and hence the final shape of the aggregate. The inclusion of loop formation reactions is shown to be crucial in obtaining physically realistic equilibrium solutions of the kinetic equations. 11 references, 3 figures.

  15. Red Blood Cell Transfusion Strategies in Adult and Pediatric Patients with Malignancy.

    PubMed

    Roubinian, Nareg; Carson, Jeffrey L

    2016-06-01

    Anemia in patients with malignancy is common as a consequence of their disease and treatment. Substantial progress has been made in the management of anemia with red blood cell transfusion in acute conditions, such as bleeding and infection, through the performance of large clinical trials. These trials suggest that transfusion at lower hemoglobin thresholds (restrictive transfusion ∼7-8 g/dL) is safe and in some cases superior to higher transfusion thresholds (liberal transfusion ∼9-10 g/dL). However, additional studies are needed in patients with malignancy to understand best practice in relation to quality of life as well as clinical outcomes. PMID:27112994

  16. Prediction of noninertial focusing of red blood cells in Poiseuille flow

    NASA Astrophysics Data System (ADS)

    Hariprasad, Daniel S.; Secomb, Timothy W.

    2015-09-01

    The motions of a red blood cell in Poiseuille flows in a range of channel widths are simulated using a two-dimensional model. For a range of initial off-centerline distances in a 12-μ m channel, cell trajectories converge to a specific off-centerline position and exhibit tank-treading motions. This behavior coexists with initial positions that lead to migration towards the centerline. The predicted off-centerline focusing effect is shown to depend on the curvature of the flow profile and on interactions with both solid boundaries.

  17. Optical tweezers study of red blood cell aggregation and disaggregation in plasma and protein solutions

    NASA Astrophysics Data System (ADS)

    Lee, Kisung; Kinnunen, Matti; Khokhlova, Maria D.; Lyubin, Evgeny V.; Priezzhev, Alexander V.; Meglinski, Igor; Fedyanin, Andrey A.

    2016-03-01

    Kinetics of optical tweezers (OT)-induced spontaneous aggregation and disaggregation of red blood cells (RBCs) were studied at the level of cell doublets to assess RBC interaction mechanics. Measurements were performed under in vitro conditions in plasma and fibrinogen and fibrinogen + albumin solutions. The RBC spontaneous aggregation kinetics was found to exhibit different behavior depending on the cell environment. In contrast, the RBC disaggregation kinetics was similar in all solutions qualitatively and quantitatively, demonstrating a significant contribution of the studied proteins to the process. The impact of the study on assessing RBC interaction mechanics and the protein contribution to the reversible RBC aggregation process is discussed.

  18. Profiling individual human red blood cells using common-path diffraction optical tomography

    PubMed Central

    Kim, Youngchan; Shim, Hyoeun; Kim, Kyoohyun; Park, HyunJoo; Jang, Seongsoo; Park, YongKeun

    2014-01-01

    Due to its strong correlation with the pathophysiology of many diseases, information about human red blood cells (RBCs) has a crucial function in hematology. Therefore, measuring and understanding the morphological, chemical, and mechanical properties of individual RBCs is a key to understanding the pathophysiology of a number of diseases in hematology, as well as to opening up new possibilities for diagnosing diseases in their early stages. In this study, we present the simultaneous and quantitative measurement of the morphological, chemical, and mechanical parameters of individual RBCs employing optical holographic microtomography. In addition, it is demonstrated that the correlation analyses of these RBC parameters provide unique information for distinguishing and understanding diseases. PMID:25322756

  19. Orientation of red blood cells and rouleaux disaggregation in interference laser fields.

    PubMed

    Kruchenok, J V; Bushuk, S B; Kurilo, G I; Nemkovich, N A; Rubinov, A N

    2005-01-01

    The effect of interference laser fields on red blood cells (RBCs) was investigated both theoretically and experimentally. The optical trapping and orientation of individual RBC in interference fringes were observed. It was found that RBC rouleaux undergo disaggregation under the action of interference laser fields. To describe the effect of RBC orientation in interference fringes, we used the equation for torque exerted on a discoid dielectric particle in a gradient light field. The experimental results are in agreement with the predictions of the developed theoretical model. PMID:23345885

  20. Prediction of non-inertial focusing of red blood cells in Poiseuille flow

    PubMed Central

    Hariprasad, Daniel S.; Secomb, Timothy W.

    2016-01-01

    The motions of a red blood cell in Poiseuille flows in a range of channel widths are simulated using a two-dimensional model. For a range of initial off-centerline distances in a 12-μm channel, cell trajectories converge to a specific off-centerline position and exhibit tank-treading motions. This behavior coexists with initial positions that lead to migration towards the centerline. The predicted off-centerline focusing effect is shown to depend on the curvature of the flow profile and on interactions with both solid boundaries. PMID:26465557

  1. Static and dynamic light scattering of healthy and malaria-parasite invaded red blood cells

    NASA Astrophysics Data System (ADS)

    Park, Yongkeun; Diez-Silva, Monica; Fu, Dan; Popescu, Gabriel; Choi, Wonshik; Barman, Ishan; Suresh, Subra; Feld, Michael S.

    2010-03-01

    We present the light scattering of individual Plasmodium falciparum-parasitized human red blood cells (Pf-RBCs), and demonstrate progressive alterations to the scattering signal arising from the development of malaria-inducing parasites. By selectively imaging the electric fields using quantitative phase microscopy and a Fourier transform light scattering technique, we calculate the light scattering maps of individual Pf-RBCs. We show that the onset and progression of pathological states of the Pf-RBCs can be clearly identified by the static scattering maps. Progressive changes to the biophysical properties of the Pf-RBC membrane are captured from dynamic light scattering.

  2. Columnar deformation of human red blood cell by highly localized fiber optic Bessel beam stretcher.

    PubMed

    Lee, Sungrae; Joo, Boram; Jeon, Pyo Jin; Im, Seongil; Oh, Kyunghwan

    2015-11-01

    A single human red blood cell was optically stretched along two counter-propagating fiber-optic Bessel-like beams in an integrated lab-on-a-chip structure. The beam enabled highly localized stretching of RBC, and it induced a nonlinear mechanical deformation to finally reach an irreversible columnar shape that has not been reported. We characterized and systematically quantified this optically induced mechanical deformation by the geometrical aspect ratio of stretched RBC and the irreversible stretching time. The proposed RBC mechanism can realize a versatile and compact opto-mechanical platform for optical diagnosis of biological substances in the single cell level. PMID:26601005

  3. Autologous Doping with Cryopreserved Red Blood Cells - Effects on Physical Performance and Detection by Multivariate Statistics.

    PubMed

    Malm, Christer B; Khoo, Nelson S; Granlund, Irene; Lindstedt, Emilia; Hult, Andreas

    2016-01-01

    The discovery of erythropoietin (EPO) simplified blood doping in sports, but improved detection methods, for EPO has forced cheating athletes to return to blood transfusion. Autologous blood transfusion with cryopreserved red blood cells (RBCs) is the method of choice, because no valid method exists to accurately detect such event. In endurance sports, it can be estimated that elite athletes improve performance by up to 3% with blood doping, regardless of method. Valid detection methods for autologous blood doping is important to maintain credibility of athletic performances. Recreational male (N = 27) and female (N = 11) athletes served as Transfusion (N = 28) and Control (N = 10) subjects in two different transfusion settings. Hematological variables and physical performance were measured before donation of 450 or 900 mL whole blood, and until four weeks after re-infusion of the cryopreserved RBC fraction. Blood was analyzed for transferrin, iron, Hb, EVF, MCV, MCHC, reticulocytes, leucocytes and EPO. Repeated measures multivariate analysis of variance (MANOVA) and pattern recognition using Principal Component Analysis (PCA) and Orthogonal Projections of Latent Structures (OPLS) discriminant analysis (DA) investigated differences between Control and Transfusion groups over time. Significant increase in performance (15 ± 8%) and VO2max (17 ± 10%) (mean ± SD) could be measured 48 h after RBC re-infusion, and remained increased for up to four weeks in some subjects. In total, 533 blood samples were included in the study (Clean = 220, Transfused = 313). In response to blood transfusion, the largest change in hematological variables occurred 48 h after blood donation, when Control and Transfused groups could be separated with OPLS-DA (R2 = 0.76/Q2 = 0.59). RBC re-infusion resulted in the best model (R2 = 0.40/Q2 = 0.10) at the first sampling point (48 h), predicting one false positive and one false negative. Over all, a 25% and 86% false positives ratio was

  4. Mononuclear cells from a rare blood donor, after freezing under good manufacturing practice conditions, generate red blood cells that recapitulate the rare blood phenotype

    PubMed Central

    Masiello, Francesca; Tirelli, Valentina; Sanchez, Massimo; van den Akker, Emile; Girelli, Gabriella; Marconi, Maurizio; Villa, Maria Antonietta; Rebulla, Paolo; Hashmi, Gazala; Whitsett, Carolyn; Migliaccio, Anna Rita

    2013-01-01

    Background Cultured red blood cells (cRBCs) from cord blood (CB) have been proposed as transfusion products. Whether buffy-coats discarded from blood donations (AB) may be used to generate cRBCs for transfusion has not been investigated. Study Design and Methods Erythroid progenitor cell content and numbers and blood group antigen profiles of erythroblasts (ERYs) and cRBCs generated in Human Erythroid Massive Amplification (HEMA) culture by CB (n=7) and AB (n=33, three females, three males, one AB with rare blood antigens cryopreserved using CB protocols) were compared. Results Variability was observed both in progenitor cell content (2-fold) and number of ERYs generated (1-log) by CB and AB in HEMA. The average progenitor cell contents of the subset of AB and CB analyzed were similar. AB generated numbers of ERYs 3-times lower (p<0.01) than CB in HEMA containing fetal bovine serum but similar to CB in HEMA containing human proteins. Female AB contained 2-times less (p<0.05) erythroid progenitor cells but generated numbers of ERYs similar to those generated by male AB. Cryopreserved AB with a rare blood group phenotype and shipped to another laboratory generated great numbers of ERYs, 90% of which matured into cRBCs. Blood group antigen expression was consistent with the donor genotype for ERYs generated both by CB and AB but concordant with that of native RBCs only for cells derived from AB. Conclusion Buffy-coats from regular donors, including a donor with rare phenotypes stored under conditions established for CB, are not inferior to CB for the generation of cRBCs. PMID:24004289

  5. Mature red blood cells: from optical model to inverse light-scattering problem

    PubMed Central

    Gilev, Konstantin V.; Yurkin, Maxim A.; Chernyshova, Ekaterina S.; Strokotov, Dmitry I.; Chernyshev, Andrei V.; Maltsev, Valeri P.

    2016-01-01

    We propose a method for characterization of mature red blood cells (RBCs) morphology, based on measurement of light-scattering patterns (LSPs) of individual RBCs with the scanning flow cytometer and on solution of the inverse light-scattering (ILS) problem for each LSP. We considered a RBC shape model, corresponding to the minimal bending energy of the membrane with isotropic elasticity, and constructed an analytical approximation, which allows rapid simulation of the shape, given the diameter and minimal and maximal thicknesses. The ILS problem was solved by the nearest-neighbor interpolation using a preliminary calculated database of 250,000 theoretical LSPs. For each RBC in blood sample we determined three abovementioned shape characteristics and refractive index, which also allows us to calculate volume, surface area, sphericity index, spontaneous curvature, hemoglobin concentration and content. PMID:27446656

  6. Disaggregation of stacked red blood cells under strong pulse magnetic field

    NASA Astrophysics Data System (ADS)

    Hwang, Do-Guwn; Park, Hyeji; Kim, Woori; Lee, Jinyoung; Lee, Hyun Sook

    2015-05-01

    We have investigated the dependence of magnetic field intensity and stimulation time on stacking formation of red blood cells (RBCs) to study blood circulation in human body. The pulse magnetic field with the maximum intensity of 0.27-0.07 T, pulse transition time of 0.102 ms, and pulse intervals of 1 s was applied to the distal end of palm for 5-20 min. The aggregation of RBCs was measured using microscopy. After the magnetic stimulation for 10 min, the fully stacked RBCs were almost separated from each other and moved much faster than those in unstimulated state. The disaggregation was maintained at a decreasing intensity of 0.19 T, and a few cells were stacked at the weak intensity of 0.07 T. In this work, we investigated the degree of RBCs aggregation and activity time by varying the intensity and time of magnetic stimulation to get the optimum condition of pulse magnetic field stimulus.

  7. Volumetric measurement of human red blood cells by MOSFET-based microfluidic gate.

    PubMed

    Guo, Jinhong; Ai, Ye; Cheng, Yuanbing; Li, Chang Ming; Kang, Yuejun; Wang, Zhiming

    2015-08-01

    In this paper, we present a MOSFET-based (metal oxide semiconductor field-effect transistor) microfluidic gate to characterize the translocation of red blood cells (RBCs) through a gate. In the microfluidic system, the bias voltage modulated by the particles or biological cells is connected to the gate of MOSFET. The particles or cells can be detected by monitoring the MOSFET drain current instead of DC/AC-gating method across the electronic gate. Polystyrene particles with various standard sizes are utilized to calibrate the proposed device. Furthermore, RBCs from both adults and newborn blood sample are used to characterize the performance of the device in distinguishing the two types of RBCs. As compared to conventional DC/AC current modulation method, the proposed device demonstrates a higher sensitivity and is capable of being a promising platform for bioassay analysis. PMID:25349117

  8. Boundary element simulation of backscattering properties for red blood with high frequency ultrasonic transducers.

    PubMed

    Wu, Shih-Jeh; Kuo, Ihyuan; Shung, K Kirk

    2005-01-01

    High frequency ultrasonic imaging (e.g. >30 MHz) from blood is difficult due to its tenuous backscattered pressure and the interference from adjacent tissues as well. To increase the sensitivity focused transducer has to be used, thus raising the complexity of interpreting the received signals. A numerical simulation of the ultrasonic scattering property from erythrocyte and rouleaux based on boundary element method was performed with experimental results based on a modified substitution method. The results (proportional relationship between backscattered pressure and frequency and the frequency limit for Rayleigh scattering) closely coincide with experimental data for erythrocyte. Rouleaux model results also show the dependence of degree of red cell aggregation on backscattering properties. The boundary element method serves as a good means to calculate the acoustic scattering from blood cells under arbitrary incident waves. PMID:15556649

  9. Using mechanobiological mimicry of red blood cells to extend circulation times of hydrogel microparticles

    PubMed Central

    Merkel, Timothy J.; Jones, Stephen W.; Herlihy, Kevin P.; Kersey, Farrell R.; Shields, Adam R.; Napier, Mary; Luft, J. Christopher; Wu, Huali; Zamboni, William C.; Wang, Andrew Z.; Bear, James E.; DeSimone, Joseph M.

    2011-01-01

    It has long been hypothesized that elastic modulus governs the biodistribution and circulation times of particles and cells in blood; however, this notion has never been rigorously tested. We synthesized hydrogel microparticles with tunable elasticity in the physiological range, which resemble red blood cells in size and shape, and tested their behavior in vivo. Decreasing the modulus of these particles altered their biodistribution properties, allowing them to bypass several organs, such as the lung, that entrapped their more rigid counterparts, resulting in increasingly longer circulation times well past those of conventional microparticles. An 8-fold decrease in hydrogel modulus correlated to a greater than 30-fold increase in the elimination phase half-life for these particles. These results demonstrate a critical design parameter for hydrogel microparticles. PMID:21220299

  10. Hydrodynamic instability in a magnetically driven suspension of paramagnetic red blood cells.

    PubMed

    Kashevsky, B E; Zholud, A M; Kashevsky, S B

    2015-09-01

    We investigate the magnetically driven motion in suspensions of paramagnetic particles. Our object is diluted deoxygenated whole blood with paramagnetic red blood cells (RBCs). We use direct observations in a closed vertical Hele-Shaw channel, and a well-defined magnetic force field applied horizontally in the channel plane. At very low cell concentrations, we register single-particle motion mode, track individual cells and determine their hydrodynamic and magnetic characteristics. Above 0.2 volume percent concentration, we observe local swirls and a global transient quasi-periodic vortex structure, intensifying with increasing cell concentration, but surprisingly this does not influence the time and purity of the magnetic extraction of RBCs. Our observations shed light on the behavioral complexity of magnetically driven submagnetic suspensions, an important issue for the emerging microfluidic technology of direct magnetic cell separation and intriguing for the mechanics of particulate soft matter. PMID:26212385

  11. Influence of red blood cell clustering on phase separation in capillary networks

    NASA Astrophysics Data System (ADS)

    Podgorski, Thomas; Boucly, Celine; Coupier, Gwennou

    2014-11-01

    We investigate the flow of red blood cell suspensions in microfluidic bifurcations and capillary networks. At strong degrees of confinement, such as those encountered in the microcirculation, phase separation takes place at bifurcations of the network, leading to strong heterogeneities and fluctuations of the hematocrit (blood cell concentration). We highlight the influence of the mechanical properties of cells : an increase of membrane or cytoplasm rigidity, as can happen in pathologies such as sickle cell disease tends to reduce the phase separation. The influence of the attractive interaction between cells, that leads to clustering (rouleau formation) was also investigated by varying the concentration of macromolecules in the solution (dextran or fibrinogen). We show that hydrodynamic stresses in bifurcations can lead to rupture of clusters at a critical speed which increases with interaction energy. Overall, the clustering phenomenon tends to increase phase separation and hematocrit heterogeneities.

  12. Men with Sickle Cell Anemia and Priapism Exhibit Increased Hemolytic Rate, Decreased Red Blood Cell Deformability and Increased Red Blood Cell Aggregate Strength

    PubMed Central

    Cita, Kizzy-Clara; Brureau, Laurent; Lemonne, Nathalie; Billaud, Marie; Connes, Philippe; Ferdinand, Séverine; Tressières, Benoit; Tarer, Vanessa; Etienne-Julan, Maryse; Blanchet, Pascal; Elion, Jacques; Romana, Marc

    2016-01-01

    Objectives To investigate the association between priapism in men with sickle cell anemia (SCA) and hemorheological and hemolytical parameters. Materials and Methods Fifty-eight men with SCA (median age: 38 years) were included; 28 who had experienced priapism at least once during their life (priapism group) and 30 who never experienced this complication (control group). Twenty-two patients were treated with hydroxycarbamide, 11 in each group. All patients were at steady state at the time of inclusion. Hematological and biochemical parameters were obtained through routine procedures. The Laser-assisted Optical Rotational Cell Analyzer was used to measure red blood cell (RBC) deformability at 30 Pa (ektacytometry) and RBC aggregation properties (laser backscatter versus time). Blood viscosity was measured at a shear rate of 225 s-1 using a cone/plate viscometer. A principal component analysis was performed on 4 hemolytic markers (i.e., lactate dehydrogenase (LDH), aspartate aminotransferase (ASAT), total bilirubin (BIL) levels and reticulocyte (RET) percentage) to calculate a hemolytic index. Results Compared to the control group, patients with priapism exhibited higher ASAT (p = 0.01), LDH (p = 0.03), RET (p = 0.03) levels and hemolytic indices (p = 0.02). Higher RBC aggregates strength (p = 0.01) and lower RBC deformability (p = 0.005) were observed in patients with priapism compared to controls. After removing the hydroxycarbamide-treated patients, RBC deformability (p = 0.01) and RBC aggregate strength (p = 0.03) were still different between the two groups, and patients with priapism exhibited significantly higher hemolytic indices (p = 0.01) than controls. Conclusion Our results confirm that priapism in SCA is associated with higher hemolytic rates and show for the first time that this complication is also associated with higher RBC aggregate strength and lower RBC deformability. PMID:27145183

  13. Predictive value of red blood cell distribution width for coronary artery lesions in patients with Kawasaki disease.

    PubMed

    Xu, Haiyan; Fu, Songling; Wang, Wei; Zhang, Qing; Hu, Jian; Gao, Lichao; Zhu, Weihua; Gong, Fangqi

    2016-08-01

    Recent studies have shown that elevated red blood cell distribution width is associated with poor outcome in cardiovascular diseases. In order to assess the predictive value of red blood cell distribution width, before treatment with intravenous immunoglobulins, for coronary artery lesions in patient with Kawasaki disease, we compared 83 patients with coronary artery lesions and 339 patients without coronary artery lesions before treatment with intravenous immunoglobulin. Clinical, echocardiographic, and biochemical values were evaluated along with red blood cell distribution width. A total of 422 consecutive patients with Kawasaki disease were enrolled into our study. According to receiver operating characteristic curve analysis, the optimal red blood cell distribution width cut-off value for predicting coronary artery lesions was 14.55% (area under the curve was 0.721; p=0.000); eighty-three patients (19.7%) had coronary artery lesions, and 70% of the patients with coronary artery lesions had red blood cell distribution width level >14.55%. Logistic regression analysis revealed that fever duration >14 days (odds ratio was 3.42, 95% confidence interval was 1.27-9.22; p=0.015), intravenous immunoglobulin resistance (odds ratio was 2.33, 95% confidence interval was 1.02-5.29; p=0.04), and red blood cell distribution width >14.55% (odds ratio was 3.49, 95% confidence interval was 2.01-6.05; p=0.000) were independent predictors of coronary artery lesions in patients with Kawasaki disease. In Conclusion, red blood cell distribution width may be helpful for predicting coronary artery lesions in patients with Kawasaki disease. PMID:26435202

  14. Brief report: a new profile of terminal N-acetyllactosamines glycans on pig red blood cells and different expression of alpha-galactose on Sika deer red blood cells and nucleated cells.

    PubMed

    Tan, Yingxia; Gong, Feng; Li, Subo; Ji, Shouping; Lu, Yanping; Gao, Hongwei; Xu, Hua; Zhang, Yangpei

    2010-05-01

    It has been reported that: (1) large variations were found in the number of sialic acid (SA) capped with N-acetyllactosamines (SA-Galbeta1-4GlcNAc-R) and alpha-Gal epitopes (Galalpha1-3Galbeta1-4GlcNAc-R) or uncapped N-acetyllactosamines (Galbeta1-4GlcNAc-R) on different mammalian red blood cells, and on nucleated cells originating from a given tissue in various species; (2) goat, sheep, horse and mouse red blood cells lack alpha-Gal epitopes, despite the expression of this epitope on a variety of nucleated cells in these species, including lymphocytes differentiated from the same hematopoietic origin. In this study, flow cytometry and Western blot analyses of pig red blood cells showed that alpha-Gal epitopes on pig red cells developed concomitantly after treatment with neuraminidase, suggesting that the terminal N-acetyllactosaminide glycans were capped with SA-alpha-Gal epitopes. Whereas, the expression of the alpha-Gal epitopes on red blood cells from Sika deer (Cevus nippon hortulorum) were found to be absent even though the epitopes were present on their white blood cells. Thus, these results add new data not only for the terminal carbohydrate structures on cell surface glycans of various mammalian cells, but also for wide variety of epitope expression on the cells from different tissues, which might be useful for understanding their unique states resulting from differentiation and evolution. PMID:20422448

  15. Alterations in Red Blood Cell Deformability during Storage: A Microfluidic Approach

    PubMed Central

    Cluitmans, Judith C. A.; Chokkalingam, Venkatachalam; Janssen, Arno M.; Brock, Roland; Huck, Wilhelm T. S.; Bosman, Giel J. C. G. M.

    2014-01-01

    Red blood cells (RBCs) undergo extensive deformation when travelling through the microcapillaries. Deformability, the combined result of properties of the membrane-cytoskeleton complex, the surface area-to-volume ratio, and the hemoglobin content, is a critical determinant of capillary blood flow. During blood bank storage and in many pathophysiological conditions, RBC morphology changes, which has been suggested to be associated with decreased deformability and removal of RBC. While various techniques provide information on the rheological properties of stored RBCs, their clinical significance is controversial. We developed a microfluidic approach for evaluating RBC deformability in a physiologically meaningful and clinically significant manner. Unlike other techniques, our method enables a high-throughput determination of changes in deformation capacity to provide statistically significant data, while providing morphological information at the single-cell level. Our data show that, under conditions that closely mimic capillary dimensions and flow, the capacity to deform and the capacity to relax are not affected during storage in the blood bank. Our data also show that altered cell morphology by itself does not necessarily affect deformability. PMID:25295273

  16. Donor-variation effect on red blood cell storage lesion: A close relationship emerges.

    PubMed

    Tzounakas, Vassilis L; Kriebardis, Anastasios G; Papassideri, Issidora S; Antonelou, Marianna H

    2016-08-01

    Although the molecular pathways leading to the progressive deterioration of stored red blood cells (RBC storage lesion) and the clinical relevance of storage-induced changes remain uncertain, substantial donor-specific variability in RBC performance during storage, and posttransfusion has been established ("donor-variation effect"). In-bag hemolysis and numerous properties of the RBC units that may affect transfusion efficacy have proved to be strongly donor-specific. Donor-variation effect may lead to the production of highly unequal blood labile products even when similar storage strategy and duration are applied. Genetic, undiagnosed/subclinical medical conditions and lifestyle factors that affect RBC characteristics at baseline, including RBC lifespan, energy metabolism, and sensitivity to oxidative stress, are all likely to influence the storage capacity of individual donors' cells, although not evident by the donor's health or hematological status at blood donation. Consequently, baseline characteristics of the donors, such as membrane peroxiredoxin-2 and serum uric acid concentration, have been proposed as candidate biomarkers of storage quality. This review article focuses on specific factors that might contribute to the donor-variation effect and emphasizes the emerging need for using omics-based technologies in association with in vitro and in vivo transfusion models and clinical trials to discover biomarkers of storage quality and posttransfusion recovery in donor blood. PMID:27095294

  17. Red blood cell cluster separation from digital images for use in sickle cell disease.

    PubMed

    González-Hidalgo, Manuel; Guerrero-Peña, F A; Herold-García, S; Jaume-I-Capó, Antoni; Marrero-Fernández, P D

    2015-07-01

    The study of cell morphology is an important aspect of the diagnosis of some diseases, such as sickle cell disease, because red blood cell deformation is caused by these diseases. Due to the elongated shape of the erythrocyte, ellipse adjustment and concave point detection are applied widely to images of peripheral blood samples, including during the detection of cells that are partially occluded in the clusters generated by the sample preparation process. In the present study, we propose a method for the analysis of the shape of erythrocytes in peripheral blood smear samples of sickle cell disease, which uses ellipse adjustments and a new algorithm for detecting notable points. Furthermore, we apply a set of constraints that allow the elimination of significant image preprocessing steps proposed in previous studies. We used three types of images to validate our method: artificial images, which were automatically generated in a random manner using a computer code; real images from peripheral blood smear sample images that contained normal and elongated erythrocytes; and synthetic images generated from real isolated cells. Using the proposed method, the efficiency of detecting the two types of objects in the three image types exceeded 99.00%, 98.00%, and 99.35%, respectively. These efficiency levels were superior to the results obtained with previously proposed methods using the same database, which is available at http://erythrocytesidb.uib.es/. This method can be extended to clusters of several cells and it requires no user inputs. PMID:25216490

  18. Identification of red blood cell rouleaux formation using photoacoustic ultrasound spectroscopy

    NASA Astrophysics Data System (ADS)

    Kibria, Fayruz; Hysi, Eno; Strohm, Eric M.; Kolios, Michael C.

    2014-03-01

    Red blood cell (RBC) rouleaux formation is a reversible phenomenon that occurs during low blood flow and small shearing forces in circulation. Certain pathological conditions can alter the molecular constituents of blood and properties of the RBCs leading to enhanced rouleaux formation, which results in impaired perfusion and tissue oxygenation. In this study rouleaux were artificially generated using Dextran-70 and examined using a photoacoustic (PA) microscope. Individual rouleau were irradiated with a 532 nm pulsed laser focused to a 10 μm spot size, and the resulting PA signals recorded with a 200 MHz transducer. The laser and transducer were co-aligned, with the sample positioned between them. The frequency-domain PA ultrasound spectra were calculated for rouleaux with lengths ranging from 10 to 20 μm. For the rouleaux, a single spectral minimum at 269+/-4 MHz was observed. The spectral minima were in good agreement with a theoretical thermoelastic expansion model using an infinite length cylindrical absorber, bearing a diameter equivalent to an average human RBC (7.8 μm). These results suggest that PA ultrasound spectroscopy can be potentially used as a tool for monitoring blood samples for the presence of rouleaux.

  19. Effects of red blood cell aggregates dissociation on the estimation of ultrasound speckle image velocimetry.

    PubMed

    Yeom, Eunseop; Nam, Kweon-Ho; Paeng, Dong-Guk; Lee, Sang-Joon

    2014-08-01

    Ultrasound speckle image of blood is mainly attributed by red blood cells (RBCs) which tend to form RBC aggregates. RBC aggregates are separated into individual cells when the shear force is over a certain value. The dissociation of RBC aggregates has an influence on the performance of ultrasound speckle image velocimetry (SIV) technique in which a cross-correlation algorithm is applied to the speckle images to get the velocity field information. The present study aims to investigate the effect of the dissociation of RBC aggregates on the estimation quality of SIV technique. Ultrasound B-mode images were captured from the porcine blood circulating in a mock-up flow loop with varying flow rate. To verify the measurement performance of SIV technique, the centerline velocity measured by the SIV technique was compared with that measured by Doppler spectrograms. The dissociation of RBC aggregates was estimated by using decorrelation of speckle patterns in which the subsequent window was shifted as much as the speckle displacement to compensate decorrelation caused by in-plane loss of speckle patterns. The decorrelation of speckles is considerably increased according to shear rate. Its variations are different along the radial direction. Because the dissociation of RBC aggregates changes ultrasound speckles, the estimation quality of SIV technique is significantly correlated with the decorrelation of speckles. This degradation of measurement quality may be improved by increasing the data acquisition rate. This study would be useful for simultaneous measurement of hemodynamic and hemorheological information of blood flows using only speckle images. PMID:24794508

  20. Modeling of Shear-Induced Red Blood Cell Migration for Guiding Microfluidic Device Design

    NASA Astrophysics Data System (ADS)

    Durant, Eden; Higgins, Adam; Sharp, Kendra

    2014-11-01

    Through refinement and extension of a two-phase flow model previously reported for modeling blood in cylindrical flows (Gidaspow, 2009), we have developed a computational model for blood flow in complex microfluidic. Treating plasma as a Newtonian fluid and the Red Blood Cells (RBCs) as a granular phase, whose local concentrations are determined statistically, we have captured the migration of RBCs and concomitant formation of a cell free plasma layer at the channel walls. This model provides us with a three-dimensional distribution of RBCs and the development of the stead-state flow profile, and enables us to study the influence of complex microfluidic geometries, including flow obstacles and varying channel dimensions, on the rate and extent of RBC margination. Simulations on 50 and 100 micron square channels match observed trends including decreasing RBC margination rate in larger channels, increasing RBC margination rate with higher hematocrit, and decreasing cell free layer width with increasing hematocrit. This predictive capability will allow microfluidic devices to be tailored and optimized for specific biomedical applications such as separation of blood constituents.

  1. The wall traction induced by flowing red blood cells in model microvessels and its potential mechanotransduction

    NASA Astrophysics Data System (ADS)

    Freund, Jonathan; Vermot, Julien

    2013-11-01

    There is evidence in early embryonic development, even well before advective oxygen transport is important, that the presence of red bloods cells per se trigger essential steps of normal vascular development. For example, showed that sequestration of blood cells early in the development of a mouse, such that the hematocrit is reduced, suppresses normal vascular network development. Vascular development also provides a model for remodeling and angiogenesis. We consider the transient stresses associated with blood cells flowing in model microvessels of comparable diameter to those at early stages of development (6 μm to 12 μm). A detailed simulation tool is used to show that passing blood cells present a significant fluctuating traction signature on the vessel wall, well above the mean stresses. This is particularly pronounced for slow flows (<= 50 μm/s) or small diameters (<= 7 μm), for which root-mean-square wall traction fluctuations can exceed their mean. These events potentially present mechanotranduction triggers that direct development or remodeling. Attenuation of such fluctuating tractions by a viscoelastic endothelial glycocalyx layer is also considered. NSF supported.

  2. Red Blood Cell Dispersion in Morphologically-Inspired Microfluidic Models of Alveolar Capillary Networks

    NASA Astrophysics Data System (ADS)

    Stauber, Hagit; Fishler, Rami; Waisman, Dan; Sznitman, Josue

    2014-11-01

    Microfluidics is frequently used to study blood flow characteristics in microcapillary networks and investigate transport properties of red blood cells (RBC). To date, most of microfluidic studies have not focused on the specific morphology of alveolar capillary networks (ACN), with characteristic length scales of ~ 5 μm, known to give rise to organ-specific blood flow characteristics. To better understand flow characteristics and dispersion of RBCs in ACNs, we have designed morphologically-inspired microfluidic models of alveolar capillary beds at a real scale. We fabricate lab-on-chip devices featuring confined staggered pillar arrays with diameters of ~ 10 μm, representative of the dense ACN capillary meshes. Devices are supplied by an external reservoir containing whole blood at various hematocrit levels, to mimic RBC perfusion (Re < 0.01) within alveolar capillaries. Whole-field velocity patterns are imaged (PIV) and RBC motion is tracked using particle tracking velocimetry (PTV) from which dispersion coefficients are extracted. Our efforts are aimed at delivering a real-scale quantitative description of the pulmonary ACN microcirculation.

  3. Influence of red cell concentration on filtration of blood cell suspensions.

    PubMed

    Schmalzer, E A; Skalak, R; Usami, S; Vayo, M; Chien, S

    1983-01-01

    Pressure-time curves obtained by passing suspensions of blood cells in Ringer solution through a 5 microns polycarbonate filter at constant flow (1.6 ml/min) were evaluated for their ability to reflect the deformability of the erythrocytes. The initial pressure reading (Pi) obtained in a quasi-steady state during the first 1-2 sec of pumping was found to be reproducible for hematocrit values between 10 and 30 percent. This Pi value was normalized by the pressure generated by the cell-free suspending medium (PO) at the same flow rate. The ratio Pi/PO was found to be linearly proportional to hematocrit up to 30 percent but independent of leukocyte concentration up to 12,000/mm3. Later portions of the curve did vary with leukocyte count. By using the equations developed from theoretical modeling of cells passing through a filter, the experimentally determined relation of Pi/PO to hematocrit, and the known geometry of the filter pores, we were able to calculate parameters reflecting the deformability of red cells. These include beta, the ratio of resistance in a pore containing a red cell to that in a pore containing only the suspending medium, and alpha, the proportion of pores filled by erythrocytes in transit. The application of theoretical analysis to experimental data has provided quantitative insights into the behavior of red cells during filtration tests in normal and disease states. PMID:6871424

  4. Antioxidant metabolism during blood storage and its relationship to post-transfusion red cell survival

    SciTech Connect

    Lachant, N.A.; Noble, N.A.; Myrhe, B.A.; Tanaka, K.R.

    1984-10-01

    The status of the erythrocyte antioxidant defense system and its relationship to post-transfusion red cell survival were determined in erythrocytes stored for 35 or 42 days in CPD-A1 anticoagulant with a saline-adenine-glucose additive. As storage progressed, there was a significant increase in incubated Heinz body formation (P less than .001) and a significant decrease in reduced glutathione (GSH) stability (P less than .001). Stimulated pentose phosphate shunt activity also declined during storage (P less than .06), while unstimulated shunt activity remained unchanged. The increase in Heinz body formation was associated with decreased GSH stability (r . -.77, P less than .001), which in turn was associated with the decline in stimulated pentose shunt activity (r . .67, P less than .001). The changes in Heinz body formation (r . -.85), GSH stability (r . .83), and stimulated pentose shunt activity (r . .54) were all significantly (P less than .001) related to the decline in adenosine triphosphate (ATP) content of the erythrocyte. Red cell survival 24 hours after transfusion was significantly related to the GSH stability (r . .80, P less than .001) and to the ATP concentration (r . .76, P less than .005) on the day of transfusion. Thus, dysfunction of the erythrocyte antioxidant defense system occurs during blood storage and appears to be related, in part, to ATP depletion. The ability to maintain a normal reduced glutathione concentration during oxidant stress appears to be an important determinant of red cell survival in the peritransfusion period.

  5. Altered red and white blood cell rheology in type II diabetes.

    PubMed

    Ernst, E; Matrai, A

    1986-12-01

    Twenty-three patients suffering from type II, non-insulin-dependent diabetes were compared with matched controls. Suspensions with standardized white and red cell counts were filtered in a novel device capable of discriminating filter occlusion and cell transit time. Results confirm previous studies indicating that red cell deformability is impaired in diabetes. According to our findings, this may be caused by a slight overall loss of red cell fluidity together with the existence of a subpopulation of more markedly rigid erythrocytes. Furthermore, we demonstrate that white cell filterability is reduced in type II diabetes. This could be due to decreased white cell deformability, increased white cell adhesion, or both. Analysis of diabetic subgroups indicates that the white cell rheology is impaired to a greater extent in patients taking oral antidiabetic drugs than in patients controlled by diet alone. Altered white cell rheology could help to explain the pathological blood cell filterability frequently reported in diabetes. More important, impaired white cell rheology might significantly contribute to microcirculatory flow abnormalities jeopardizing O2 exchange in the terminal vascular bed. PMID:3770316

  6. Defected red blood cell membranes and direct correlation with the uraemic milieu: the connection with the decreased red blood cell lifespan observed in haemodialysis patients

    NASA Astrophysics Data System (ADS)

    Stamopoulos, D.; Grapsa, E.; Manios, E.; Gogola, V.; Bakirtzi, N.

    2012-12-01

    Together with impaired production of erythropoietin and iron deficiency, the decreased lifespan of red blood cells (RBCs) is a main factor contributing to the chronic anaemia observed in haemodialysis (HD) patients. Atomic force microscopy is employed in this work to thoroughly survey the membrane of intact RBCs (iRBCs) of HD patients in comparison to those of healthy donors, aiming to obtain direct information on the structural status of RBCs that can be related to their decreased lifespan. We observed that the iRBC membrane of the HD patients is overpopulated with extended circular defects, termed ‘orifices’, that have typical dimension ranging between 0.2 and 1.0 μm. The ‘orifice’ index—that is, the mean population of ‘orifices’ per top membrane surface—exhibits a pronounced relative increase of order 54 ± 12% for the HD patients as compared to healthy donors. Interestingly, for the HD patients, the ‘orifice’ index, which relates to the structural status of the RBC membrane, correlates strongly with urea concentration, which is a basic index of the uraemic milieu. Thus, these results indicate that the uraemic milieu downgrades the structural status of the RBC membrane, possibly triggering biochemical processes that result in their premature elimination from the circulation. This process could decrease the lifespan of RBCs, as observed in HD patients.

  7. Is blood pressure control for stroke prevention the correct goal? The lost opportunity of preventing hypertension

    PubMed Central

    Howard, George; Banach, Maciej; Mary, Cushman; Goff, David C.; Howard, Virginia J.; Lackland, Daniel T.; McVay, Jim; Meschia, James F.; Muntner, Paul; Oparil, Suzanne; Rightmyer, Melanie; Taylor, Herman A.

    2016-01-01

    Background and Purpose While pharmacologic treatment of hypertension has important health benefits, it does not capture the benefit of maintenance of ideal health through the prevention or delay of hypertension. Methods 26,875 black and white participants aged 45+, were assessed and followed for incident stroke events. The association was assessed between incident stroke and: 1) systolic blood pressure categorized as normal (< 120 mmHg), prehypertension (120–139 mmHg), stage-1 hypertension (140–159 mmHg) and stage-2 hypertension (160 mmHg+), and 2) number of classes of antihypertensive medications, classified as none, 1, 2, or 3 or more. Results During 6.3 years of follow-up, 823 stroke events occurred. Nearly half (46%) of the population were successfully-treated (SBP < 140 mmHg) hypertensives. Within blood pressure strata, the risk of stroke increased with each additional class of required antihypertensive medication, with hazard ratio [HR]=1.33; 95%CI: 1.16–1.52 for normotensive, HR=1.15; 95%CI: 1.05–1.26 for prehypertension, and HR=1.22; 95%CI: 1.06–1.39 for stage 1 hypertension. A successfully treated (SBP<120 mmHg) hypertensive person on 3+ antihypertensive medication classes was at marginally higher stroke risk than a person with untreated stage 1 hypertension (HR=2.48 versus HR=2.19, relative to those with SBP <120 on no antihypertensive medications). Conclusions Maintaining the normotensive status solely through pharmacologic treatment has a profound impact, as nearly half of this general population cohort were treated to guideline (SBP<140 mmHg) but failed to return to risk levels similar to normotensive individuals. Even with successful treatment there is a substantial potential gain by prevention or delay of hypertension. PMID:25953369

  8. Seroprevalence of unexpected red blood cell antibodies among pregnant women in Uganda.

    PubMed

    Eipl, K; Nakabiito, C; Bwogi, K; Motevalli, M; Roots, A; Blagg, L; Jackson, J B

    2012-01-01

    We conducted a population-based, cross-sectional study among pregnant women in Kampala, Uganda, to determine ABO and D blood types and to determine the percentage who have unexpected red blood cell (RBC) antibodies and their specificities. De-identified blood samples from routine testing of 1001 pregnant women at the Mulago Hospital antenatal clinics in Kampala were typed for ABO and D and screened for the presence of unexpected RBC antibodies with confirmation and subsequent antibody identification. Of the 1001 blood samples tested, 48.9 percent, 26.4 percent, 21.0 percent, and 3.8 percent tested positive for blood groups 0, A, B, and AB, respectively. Of these samples, 23 (2.3%)were negative forD, and 55 (5.5%) showed initial reactivity with at least one screening RBC. The RBC antibody screen was repeated on these 55 samples, and antibody identification was performed at the Johns Hopkins Hospital Blood Bank in Baltimore, Maryland. Twenty-one of the 55 samples were confirmed to have evidence of agglutination. Nine of the 21 samples demonstrated the presence of clinically significant RBC antibodies with anti-S being the most common, 8 samples demonstrated the presence of benign or naturally occurring antibodies, and 4 had only inconclusive reactivity. This study revealed a relatively high frequency of D and a low frequency of demonstrable clinically significant alloantibodies that may cause hemolytic disease of the newborn or hemolytic transfusion reactions among pregnant women in Kampala, with anti-S being the most frequent antibody specificity. PMID:23421539

  9. Detection and quantification of subtle changes in red blood cell density using a cell phone.

    PubMed

    Felton, Edward J; Velasquez, Anthony; Lu, Shulin; Murphy, Ryann O; ElKhal, Abdala; Mazor, Ofer; Gorelik, Pavel; Sharda, Anish; Ghiran, Ionita C

    2016-08-16

    Magnetic levitation has emerged as a technique that offers the ability to differentiate between cells with different densities. We have developed a magnetic levitation system for this purpose that distinguishes not only different cell types but also density differences in cells of the same type. This small-scale system suspends cells in a paramagnetic medium in a capillary placed between two rare earth magnets, and cells levitate to an equilibrium position determined solely by their density. Uniform reference beads of known density are used in conjunction with the cells as a means to quantify their levitation positions. In one implementation images of the levitating cells are acquired with a microscope, but here we also introduce a cell phone-based device that integrates the magnets, capillary, and a lens into a compact and portable unit that acquires images with the phone's camera. To demonstrate the effectiveness of magnetic levitation in cell density analysis we carried out levitation experiments using red blood cells with artificially altered densities, and also levitated those from donors. We observed that we can distinguish red blood cells of an anemic donor from those that are healthy. Since a plethora of disease states are characterized by changes in cell density magnetic cell levitation promises to be an effective tool in identifying and analyzing pathologic states. Furthermore, the low cost, portability, and ease of use of the cell phone-based system may potentially lead to its deployment in low-resource environments. PMID:27431921

  10. Effect of superposition and masking between red blood cell autoantibodies and alloantibodies.

    PubMed

    Yu, Y; Wang, D Q

    2014-01-01

    This study aimed to explore the law of superposition and masking between autoantibodies and alloantibodies, and to ensure the detection of alloantibodies and to improve the safety of warm autoimmune hemolytic anemia patients. Eight kinds of commercial IgG red blood cell antibody reagents were serially diluted, and 3 kinds of antibodies at dilutions showing a continuous gradual decline in agglutination strength with the corresponding antigen red blood cells were treated as the target antibodies. Anti-D and anti-M were treated as simulated autoantibodies, and anti-Fya was treated as a simulated alloantibody. Four concentrations, 4+, 3+, 2+ and 1+, of autoantibodies and three concentrations, 3+, 2+ and 1+, of alloantibodies were combined, and 12 kinds of hybrid antibodies were detected and evaluated by the anti-human globulin micro-column gel assay. When the simulated strong autoantibody (4+) was used, the alloantibodies (3+, 2+, 1+) had no effect on the final agglutination strength; when the strength of agglutination produced by the simulated autoantibody was less than 4+, and at the same time there were alloantibodies (3+, 2+, 1+), the differences in agglutination strength with a panel of RBCs could be clearly observed. Strong autoantibodies (4+) can exert a masking effect, leading to alloantibodies being undetected; autoantibodies less than 4+, will produce the superimposed effect with alloantibodies, resulting in differences in agglutination strength. PMID:25036516

  11. Fluctuations of coupled fluid and solid membranes with application to red blood cells.

    PubMed

    Auth, Thorsten; Safran, S A; Gov, Nir S

    2007-11-01

    The fluctuation spectra and the intermembrane interaction of two membranes at a fixed average distance are investigated. Each membrane can either be a fluid or a solid membrane, and in isolation, its fluctuations are described by a bare or a wave-vector-dependent bending modulus, respectively. The membranes interact via their excluded-volume interaction; the average distance is maintained by an external, homogeneous pressure. For strong coupling, the fluctuations can be described by a single, effective membrane that combines the elastic properties. For weak coupling, the fluctuations of the individual, noninteracting membranes are recovered. The case of a composite membrane consisting of one fluid and one solid membrane can serve as a microscopic model for the plasma membrane and cytoskeleton of the red blood cell. We find that, despite the complex microstructure of bilayers and cytoskeletons in a real cell, the fluctuations with wavelengths lambda greater, similar 400 nm are well described by the fluctuations of a single, polymerized membrane (provided that there are no inhomogeneities of the microstructure). The model is applied to the fluctuation data of discocytes ("normal" red blood cells), a stomatocyte, and an echinocyte. The elastic parameters of the membrane and an effective temperature that quantifies active, metabolically driven fluctuations are extracted from the experiments. PMID:18233690

  12. Surface-emitting superconductor laser spectroscopy for characterizing normal and sickled red blood cells

    SciTech Connect

    Gourley, P.L.; Meissner, K.E.; Brennan, T.M.; Hammons, B.E.; Gourley, M.F.

    1995-02-01

    We have developed a new intracavity laser technique that uses a living or a fixed cell as an integral component of the laser. The cells are placed on an AlGaAs/GaAs surface-emitting semiconductor wafer and covered with a glass dielectric mirror to form a laser resonator. In this arrangement, the cells serve as optical waveguides (or lens elements) to confine (or focus) light generated in the resonator by the semiconductor. Because of the high transparency, the cells aid the lasing process to generate laser light. This ultra sensitive laser provides a novel imaging/spectroscopic technique for histologic examination which we demonstrate with normal and sickled human red blood cells. Extremely high contrast microscopic images of the cells are observed near 830-850 nm. These images correspond to electromagnetic modes of cell structures and are sensitive to shape of the cell. Using a high resolution spectrometer, we resolve the light emitted from these images into very narrow spectral peaks associated with the lasing modes. Analysis of the spectra reveals that the distribution of peaks is quite different for normal and sickled red blood cells. This technique, in a more developed form, may be useful for the rapid analysis of other kinds of normal and abnormal cells.

  13. Spatially variant red blood cell crenation in alternating current non-uniform fieldsa

    PubMed Central

    An, Ran; Wipf, David O.; Minerick, Adrienne R.

    2014-01-01

    Alternating-current (AC) electrokinetics involve the movement and behaviors of particles or cells. Many applications, including dielectrophoretic manipulations, are dependent upon charge interactions between the cell or particle and the surrounding medium. Medium concentrations are traditionally treated as spatially uniform in both theoretical models and experiments. Human red blood cells (RBCs) are observed to crenate, or shrink due to changing osmotic pressure, over 10 min experiments in non-uniform AC electric fields. Cell crenation magnitude is examined as functions of frequency from 250 kHz to 1 MHz and potential from 10 Vpp to 17.5 Vpp over a 100 μm perpendicular electrode gap. Experimental results show higher peak to peak potential and lower frequency lead to greater cell volume crenation up to a maximum volume loss of 20%. A series of experiments are conducted to elucidate the physical mechanisms behind the red blood cell crenation. Non-uniform and uniform electrode systems as well as high and low ion concentration experiments are compared and illustrate that AC electroporation, system temperature, rapid temperature changes, medium pH, electrode reactions, and convection do not account for the crenation behaviors observed. AC electroosmotic was found to be negligible at these conditions and AC electrothermal fluid flows were found to reduce RBC crenation behaviors. These cell deformations were attributed to medium hypertonicity induced by ion concentration gradients in the spatially nonuniform AC electric fields. PMID:24753734

  14. Analysis of enzymopathies in the human red blood cells by constraint-based stoichiometric modeling approaches.

    PubMed

    Durmuş Tekir, Saliha; Cakir, Tunahan; Ulgen, Kutlu O

    2006-10-01

    The human red blood cell (RBC) metabolism is investigated by calculating steady state fluxes using constraint-based stoichiometric modeling approaches. For the normal RBC metabolism, flux balance analysis (FBA) is performed via optimization of various alternative objective functions, and the maximization of production of ATP and NADPH is found to be the primary objective of the RBC metabolism. FBA and two novel approaches, minimization of metabolic adjustment (MOMA) and regulatory on-off minimization (ROOM), which can describe the behavior of the metabolic networks in case of enzymopathies, are applied to observe the relative changes in the flux distribution of the deficient network. The deficiencies in several enzymes in RBC metabolism are investigated and the flux distributions are compared with the non-deficient FBA distribution to elucidate the metabolic changes in response to enzymopathies. It is found that the metabolism is mostly affected by the glucose-6-phosphate dehydrogenase (G6PDH) and phosphoglycerate kinase (PGK) enzymopathies, whereas the effects of the deficiency in DPGM on the metabolism are negligible. These stoichiometric modeling results are found to be in accordance with the experimental findings in the literature related to metabolic behavior of the human red blood cells, showing that human RBC metabolism can be modeled stoichiometrically. PMID:16987707

  15. Fluctuations of coupled fluid and solid membranes with application to red blood cells

    NASA Astrophysics Data System (ADS)

    Auth, Thorsten; Safran, S. A.; Gov, Nir S.

    2007-11-01

    The fluctuation spectra and the intermembrane interaction of two membranes at a fixed average distance are investigated. Each membrane can either be a fluid or a solid membrane, and in isolation, its fluctuations are described by a bare or a wave-vector-dependent bending modulus, respectively. The membranes interact via their excluded-volume interaction; the average distance is maintained by an external, homogeneous pressure. For strong coupling, the fluctuations can be described by a single, effective membrane that combines the elastic properties. For weak coupling, the fluctuations of the individual, noninteracting membranes are recovered. The case of a composite membrane consisting of one fluid and one solid membrane can serve as a microscopic model for the plasma membrane and cytoskeleton of the red blood cell. We find that, despite the complex microstructure of bilayers and cytoskeletons in a real cell, the fluctuations with wavelengths λ≳400nm are well described by the fluctuations of a single, polymerized membrane (provided that there are no inhomogeneities of the microstructure). The model is applied to the fluctuation data of discocytes (“normal” red blood cells), a stomatocyte, and an echinocyte. The elastic parameters of the membrane and an effective temperature that quantifies active, metabolically driven fluctuations are extracted from the experiments.

  16. Red blood cell PK deficiency: An update of PK-LR gene mutation database.

    PubMed

    Canu, Giulia; De Bonis, Maria; Minucci, Angelo; Capoluongo, Ettore

    2016-03-01

    Pyruvate kinase (PK) deficiency is known as being the most common cause of chronic nonspherocytic hemolytic anemia (CNSHA). Clinical PK deficiency is transmitted as an autosomal recessive trait, that can segregate neither in homozygous or in a compound heterozygous modality, respectively. Two PK genes are present in mammals: the pyruvate kinase liver and red blood cells (PK-LR) and the pyruvate kinase muscle (PK-M), of which only the first encodes for the isoenzymes normally expressed in the red blood cells (R-type) and in the liver (L-type). Several reports have been published describing a large variety of genetic defects in PK-LR gene associated to CNSHA. Herein, we present a review of about 250 published mutations and six polymorphisms in PK-LR gene with the corresponding clinical and molecular data. We consulted the PubMed website for searching mutations and papers, along with two main databases: the Leiden Open Variation Database (LOVD, https://grenada.lumc.nl/LOVD2/mendelian_genes/home.php?select_db=PKLR) and Human Gene Mutation Database (HGMD, http://www.hgmd.cf.ac.uk/ac/gene.php?gene=PKLR) for selecting, reviewing and listing the annotated PK-LR gene mutations present in literature. This paper is aimed to provide useful information to clinicians and laboratory professionals regarding overall reported PK-LR gene mutations, also giving the opportunity to harmonize data regarding PK-deficient individuals. PMID:26832193

  17. GATA2 regulates Wnt signaling to promote primitive red blood cell fate.

    PubMed

    Mimoto, Mizuho S; Kwon, Sunjong; Green, Yangsook Song; Goldman, Devorah; Christian, Jan L

    2015-11-01

    Primitive erythropoiesis is regulated in a non cell-autonomous fashion across evolution from frogs to mammals. In Xenopus laevis, signals from the overlying ectoderm are required to induce the mesoderm to adopt an erythroid fate. Previous studies in our lab identified the transcription factor GATA2 as a key regulator of this ectodermal signal. To identify GATA2 target genes in the ectoderm required for red blood cell formation in the mesoderm, we used microarray analysis to compare gene expression in ectoderm from GATA2 depleted and wild type embryos. Our analysis identified components of the non-canonical and canonical Wnt pathways as being reciprocally up- and down-regulated downstream of GATA2 in both mesoderm and ectoderm. We show that up-regulation of canonical Wnt signaling during gastrulation blocks commitment to a hematopoietic fate while down-regulation of non-canonical Wnt signaling impairs erythroid differentiation. Our results are consistent with a model in which GATA2 contributes to inhibition of canonical Wnt signaling, thereby permitting progenitors to exit the cell cycle and commit to a hematopoietic fate. Subsequently, activation of non-canonical Wnt signaling plays a later role in enabling these progenitors to differentiate as mature red blood cells. PMID:26365900

  18. The activation of the sodium pump in pig red blood cells by internal and external cations.

    PubMed

    Brand, S C; Whittam, R

    1985-05-30

    A study has been made with pig red blood cells of the activation of the sodium pump by internal and external cations. Cell Na and K concentrations were altered using a PCMBS cation loading procedure. The procedure was characterised for resultant ionic conditions, maintenance of ATP levels and fragility. The activation of the sodium pump by external K was measured in cells suspended in choline (Na-free) solutions. External Cs was used as a substitute for K and elicited lower rates of pump activity. Both the Vmax and apparent Km for 42K influx and 134Cs influx increased as internal Na concentration was raised (within the non-saturating range). Vmax/apparent Km ratios for cation influx were constant. Raising external Cs concentration exerted a similar influence on pump activation by internal Na: both the maximum pump velocity and the apparent Na-site dissociation constant (K'Na) increased. The results provide evidence for a transmembrane connection between cation binding sites on opposite faces of the membrane and are consistent with a consecutive model for the sodium pump in pig red blood cells. PMID:2581622

  19. Influence of inflammatory and lipidic parameters on red blood cell distribution width in a healthy population.

    PubMed

    Vayá, Amparo; Sarnago, Ana; Fuster, Oscar; Alis, Rafael; Romagnoli, Marco

    2015-01-01

    Red blood cell distribution width (RDW) is a routine red blood cell count parameter which has been shown to be associated with inflammatory parameters. Recently, some authors proposed that RDW seems to be a marker of an adverse lipidic profile. In order to clarify whether RDW is related to inflammation, plasma lipids, or both, we determined anthropometric, hematimetric, inflammatory and lipidic parameters in 1111 healthy subjects. RDW correlated directly with age, body mass index (BMI), inflammatory parameters (plasma viscosity, erythrocyte sedimentation rate (ESR), fibrinogen, leukocyte and neutrophil count), and inversely with iron and hematimetric parameters (P <  0.05). When subjects were divided according to gender, RDW correlated inversely with triglycerides only in women (P <  0.05). When subjects were classified into RDW-quartiles, increased RDW values were accompanied by decreased serum iron levels and hematimetric indices (P <  0.01), whereas age and inflammatory markers increased according to RDW-quartiles (P <  0.001 and P <  0.05, respectively). However, plasma lipids did not change with increasing RDW-quartiles (P >  0.05). In the linear regression analysis, age, hemoglobin, MCV (beta coefficient: 0.202, -0.234, -0.316, P <  0.001) and fibrinogen (beta coefficient: 0.059, P = 0.048) were the only independent predictors of RDW. The present study indicates that RDW is associated with inflammatory markers and hematimetric indices, but not with plasma lipid levels in a healthy population. PMID:25159489

  20. Methods for quantitative detection of antibody-induced complement activation on red blood cells.

    PubMed

    Meulenbroek, Elisabeth M; Wouters, Diana; Zeerleder, Sacha

    2014-01-01

    Antibodies against red blood cells (RBCs) can lead to complement activation resulting in an accelerated clearance via complement receptors in the liver (extravascular hemolysis) or leading to intravascular lysis of RBCs. Alloantibodies (e.g. ABO) or autoantibodies to RBC antigens (as seen in autoimmune hemolytic anemia, AIHA) leading to complement activation are potentially harmful and can be - especially when leading to intravascular lysis - fatal(1). Currently, complement activation due to (auto)-antibodies on RBCs is assessed in vitro by using the Coombs test reflecting complement deposition on RBC or by a nonquantitative hemolytic assay reflecting RBC lysis(1-4). However, to assess the efficacy of complement inhibitors, it is mandatory to have quantitative techniques. Here we describe two such techniques. First, an assay to detect C3 and C4 deposition on red blood cells that is induced by antibodies in patient serum is presented. For this, FACS analysis is used with fluorescently labeled anti-C3 or anti-C4 antibodies. Next, a quantitative hemolytic assay is described. In this assay, complement-mediated hemolysis induced by patient serum is measured making use of spectrophotometric detection of the released hemoglobin. Both of these assays are very reproducible and quantitative, facilitating studies of antibody-induced complement activation. PMID:24514151

  1. A Comparative Study of the Effect of Leukoreduction and Pre-storage Leukodepletion on Red Blood Cells during Storage

    PubMed Central

    Pertinhez, Thelma A.; Casali, Emanuela; Baroni, Fabio; Berni, Pamela; Baricchi, Roberto; Spisni, Alberto

    2016-01-01

    Blood transfusion is a fundamental therapy in numerous pathological conditions. Regrettably, many clinical reports describe adverse transfusion's drawbacks due to red blood cells alterations during storage. Thus, the possibility for a blood bank to ameliorate the quality of the erythrocyte concentrates units is crucial to improve clinical results and reduce transfusion adverse occurrences. Leukodepletion is a pre-storage treatment recognized to better preserve the quality of red blood cells with respect to leukoreduction. Aim of this work is to unravel the biochemical and biophysical basis that sustain the good clinical outcomes associated to the use of leukodepleted erythrocytes units. Erythrocytes concentrates were prepared as leukoreduced (n = 8) and pre-storage leukodepleted (n = 8) and then studied during 6 weeks in blood bank conditions. Overall, the data indicate that leukodepletion not only provide red blood cells with an appropriate amount of nutrients for a longer time but also selects red blood cells characterized by a more resilient plasma membrane fit to prolong their viability. We believe these results will stimulate new ideas to further optimize the current storage protocols. PMID:27148539

  2. Red Blood Cell Homeostasis: Pharmacological Interventions to Explore Biochemical, Morphological and Mechanical Properties.

    PubMed

    Cluitmans, Judith C A; Gevi, Federica; Siciliano, Angela; Matte, Alessandro; Leal, Joames K F; De Franceschi, Lucia; Zolla, Lello; Brock, Roland; Adjobo-Hermans, Merel J W; Bosman, Giel J G C M

    2016-01-01

    During their passage through the circulation, red blood cells (RBCs) encounter severe physiological conditions consisting of mechanical stress, oxidative damage and fast changes in ionic and osmotic conditions. In order to survive for 120 days, RBCs adapt to their surroundings by subtle regulation of membrane organization and metabolism. RBC homeostasis depends on interactions between the integral membrane protein band 3 with other membrane and cytoskeletal proteins, and with key enzymes of various metabolic pathways. These interactions are regulated by the binding of deoxyhemoglobin to band 3, and by a signaling network revolving around Lyn kinase and Src family kinase-mediated phosphorylation of band 3. Here we show that manipulation of the interaction between the lipid bilayer and the cytoskeleton, using various pharmacological agents that interfere with protein-protein interactions and membrane lipid organization, has various effects on: (1) morphology, as shown by high resolution microscopy and quantitative image analysis; (2) organization of membrane proteins, as indicated by immunofluorescence confocal microscopy and quantitative as well as qualitative analysis of vesicle generation; (3) membrane lipid organization, as indicated by flow cytometric analysis of phosphatidylserine exposure; (4) deformability, as assessed in capillary-mimicking circumstances using a microfluidics system; (5) deformability as determined using a spleen-mimicking device; (6) metabolic activity as indicated by metabolomics. Our data show that there is a complex relationship between red cell morphology, membrane organization and deformability. Also, our data show that red blood cells have a relatively high resistance to disturbance of membrane organization in vitro, which may reflect their capacity to withstand mechanical, oxidative and osmotic stress in vivo. PMID:27066490

  3. Red Blood Cell Homeostasis: Pharmacological Interventions to Explore Biochemical, Morphological and Mechanical Properties

    PubMed Central

    Cluitmans, Judith C. A.; Gevi, Federica; Siciliano, Angela; Matte, Alessandro; Leal, Joames K. F.; De Franceschi, Lucia; Zolla, Lello; Brock, Roland; Adjobo-Hermans, Merel J. W.; Bosman, Giel J. G. C. M.

    2016-01-01

    During their passage through the circulation, red blood cells (RBCs) encounter severe physiological conditions consisting of mechanical stress, oxidative damage and fast changes in ionic and osmotic conditions. In order to survive for 120 days, RBCs adapt to their surroundings by subtle regulation of membrane organization and metabolism. RBC homeostasis depends on interactions between the integral membrane protein band 3 with other membrane and cytoskeletal proteins, and with key enzymes of various metabolic pathways. These interactions are regulated by the binding of deoxyhemoglobin to band 3, and by a signaling network revolving around Lyn kinase and Src family kinase-mediated phosphorylation of band 3. Here we show that manipulation of the interaction between the lipid bilayer and the cytoskeleton, using various pharmacological agents that interfere with protein-protein interactions and membrane lipid organization, has various effects on: (1) morphology, as shown by high resolution microscopy and quantitative image analysis; (2) organization of membrane proteins, as indicated by immunofluorescence confocal microscopy and quantitative as well as qualitative analysis of vesicle generation; (3) membrane lipid organization, as indicated by flow cytometric analysis of phosphatidylserine exposure; (4) deformability, as assessed in capillary-mimicking circumstances using a microfluidics system; (5) deformability as determined using a spleen-mimicking device; (6) metabolic activity as indicated by metabolomics. Our data show that there is a complex relationship between red cell morphology, membrane organization and deformability. Also, our data show that red blood cells have a relatively high resistance to disturbance of membrane organization in vitro, which may reflect their capacity to withstand mechanical, oxidative and osmotic stress in vivo. PMID:27066490

  4. Age of red blood cells and mortality in the critically ill

    PubMed Central

    2011-01-01

    Introduction In critically ill patients, it is uncertain whether exposure to older red blood cells (RBCs) may contribute to mortality. We therefore aimed to evaluate the association between the age of RBCs and outcome in a large unselected cohort of critically ill patients in Australia and New Zealand. We hypothesized that exposure to even a single unit of older RBCs may be associated with an increased risk of death. Methods We conducted a prospective, multicenter observational study in 47 ICUs during a 5-week period between August 2008 and September 2008. We included 757 critically ill adult patients receiving at least one unit of RBCs. To test our hypothesis we compared hospital mortality according to quartiles of exposure to maximum age of RBCs without and with adjustment for possible confounding factors. Results Compared with other quartiles (mean maximum red cell age 22.7 days; mortality 121/568 (21.3%)), patients treated with exposure to the lowest quartile of oldest RBCs (mean maximum red cell age 7.7 days; hospital mortality 25/189 (13.2%)) had an unadjusted absolute risk reduction in hospital mortality of 8.1% (95% confidence interval = 2.2 to 14.0%). After adjustment for Acute Physiology and Chronic Health Evaluation III score, other blood component transfusions, number of RBC transfusions, pretransfusion hemoglobin concentration, and cardiac surgery, the odds ratio for hospital mortality for patients exposed to the older three quartiles compared with the lowest quartile was 2.01 (95% confidence interval = 1.07 to 3.77). Conclusions In critically ill patients, in Australia and New Zealand, exposure to older RBCs is independently associated with an increased risk of death. PMID:21496231

  5. Microfluidic evaluation of red cells collected and stored in modified processing solutions used in blood banking.

    PubMed

    Wang, Yimeng; Giebink, Adam; Spence, Dana M

    2014-01-01

    The most recent American Association of Blood Banks survey found that 40,000 units of blood are required daily for general medicine, hematology/oncology, surgery, and for accident and trauma victims. While blood transfusions are an extremely important component of critical healthcare, complications associated with transfusion of blood components still exist. It is well-established that the red blood cell (RBC) undergoes many physical and chemical changes during storage. Increased oxidative stress, formation of advanced glycation endproducts, and microparticle formation are all known to occur during RBC storage. Furthermore, it is also known that patients who receive a transfusion have reduced levels of available nitric oxide (NO), a major determinant in blood flow. However, the origin of this reduced NO bioavailability is not completely understood. Here, we show that a simple modification to the glucose concentration in the solutions used to process whole blood for subsequent RBC storage results in a remarkable change in the ability of these cells to stimulate NO. In a controlled in vitro microflow system, we discovered that storage of RBCs in normoglycemic versions of standard storage solutions resulted in RBC-derived ATP release values 4 weeks into storage that were significantly greater than day 1 release values for those RBCs stored in conventional solutions. During the same storage duration, microfluidic technologies enabled measurements of endothelium-derived NO that were stimulated by the ATP release from the stored RBCs. In comparison to currently accepted processing solutions, the NO production increased by more than 25% in the presence of the RBCs stored in the normoglycemic storage solutions. Control experiments using inhibitors of ATP release from the RBCs, or ATP binding to the endothelium, strongly suggest that the increased NO production by the endothelium is directly related to the ability of the stored RBCs to release ATP. We anticipate these

  6. Apoptosis and morphological alterations after UVA irradiation in red blood cells of p53 deficient Japanese medaka (Oryzias latipes).

    PubMed

    Sayed, Alla El-Din Hamid; Watanabe-Asaka, Tomomi; Oda, Shoji; Mitani, Hiroshi

    2016-08-01

    Morphological alterations in red blood cells were described as hematological bioindicators of UVA exposure to investigate the sensitivity to UVA in wild type Japanese medaka (Oryzias latipes) and a p53 deficient mutant. The fewer abnormal red blood cells were observed in the p53 mutant fish under the control conditions. After exposure to different doses of UVA radiation (15min, 30min and 60min/day for 3days), cellular and nuclear alterations in red blood cells were analyzed in the UVA exposed fish compared with non-exposed controls and those alterations included acanthocytes, cell membrane lysis, swollen cells, teardrop-like cell, hemolyzed cells and sickle cells. Those alterations were increased after the UVA exposure both in wild type and the p53 deficient fish. Moreover, apoptosis analyzed by acridine orange assay showed increased number of apoptosis in red blood cells at the higher UVA exposure dose. No micronuclei but nuclear abnormalities as eccentric nucleus, nuclear budding, deformed nucleus, and bilobed nucleus were observed in each group. These results suggested that UVA exposure induced both p53 dependent and independent apoptosis and morphological alterations in red blood cells but less sensitive to UVA than Wild type in medaka fish. PMID:27203565

  7. Interactions of dendritic glycopolymer with erythrocytes, red blood cell ghosts and membrane enzymes.

    PubMed

    Wrobel, Dominika; Janaszewska, Anna; Appelhans, Dietmar; Voit, Brigitte; Bryszewska, Maria; Maly, Jan

    2015-12-30

    Interactions between maltose functionalized hyperbranched poly(ethylene imine)s (95% maltose decoration denoted as Mal-PEI A; 33% maltose decoration denoted as Mal-PEI B) and red blood cells (RBCs) and between red blood cell membranes were investigated. We monitored the degree of hemolysis, the change in cell shape, the influence of polymers on the fluidity of the cell membrane and some cell membrane enzymes to determine their possible cytotoxic impact on them. To observe the extent of hemolysis, the RBCs were incubated with different concentrations of Mal-PEIs. The first significant lysis of RBCs was observed after 6h of incubation. Prolongation of the incubation time increased the number of ruptured cells. Moreover, we observed that Mal-PEI B was more hemolytic than Mal-PEI A in buffer solution. In contrast, an incubation of RBCs with Mal-PEIs in human plasma significantly decreased the hemolytic process and showed higher hemolytic property of Mal-PEI A compared to Mal-PEI B. Also several changes in the shape of the RBCs occurred after incubation with Mal-PEIs. Some of the erythrocytes shrank (echinocytes), but their morphology generally remained unchanged during the incubation. As shown by fluorescence experiments, both polymers induced the increase of fluidity of RBCs membranes. In summary, both types of hyperbranched poly(ethylene imine)s were practically non-hemolytic even at high polymer concentrations. Mal-PEI B was slightly more noxious than the Mal-PEI A in a buffer solution, while in blood plasma, the situation was opposite. Decrease of Na+/K+ ATPase and total ATPase enzymes activity was related with molecule size and number of maltose groups on the surface of molecule. The low hemolytic properties only observed at higher concentration (100μM and 400μM) indicated that Mal-PEIs are promising macromolecules in the area of drug delivery systems. PMID:26498371

  8. Two-dimensional simulation of red blood cell motion near a wall under a lateral force

    NASA Astrophysics Data System (ADS)

    Hariprasad, Daniel S.; Secomb, Timothy W.

    2014-11-01

    The motion of a red blood cell suspended in a linear shear flow adjacent to a fixed boundary subject to an applied lateral force directed toward the boundary is simulated. A two-dimensional model is used that represents the viscous and elastic properties of normal red blood cells. Shear rates in the range of 100 to 600 s-1 are considered, and the suspending medium viscosity is 1 cP. In the absence of a lateral force, the cell executes a tumbling motion. With increasing lateral force, a transition from tumbling to tank-treading is predicted. The minimum force required to ensure tank-treading increases nonlinearly with the shear rate. Transient swinging motions occur when the force is slightly larger than the transition value. The applied lateral force is balanced by a hydrodynamic lift force resulting from the positive orientation of the long axis of the cell with respect to the wall. In the case of cyclic tumbling motions, the orientation angle takes positive values through most of the cycle, resulting in lift generation. These results are used to predict the motion of a cell close to the outer edge of the cell-rich core region that is generated when blood flows in a narrow tube. In this case, the lateral force is generated by shear-induced dispersion, resulting from cell-cell interactions in a region with a concentration gradient. This force is estimated using previous data on shear-induced dispersion. The cell is predicted to execute tank-treading motions at normal physiological hematocrit levels, with the possibility of tumbling at lower hematocrit levels.

  9. Application of DNA-based forensic analysis for the detection of homologous transfusion of whole blood and of red blood cell concentrates in doping control.

    PubMed

    Stampella, Alessandra; Di Marco, Sabrina; Pirri, Daniela; de la Torre, Xavier; Botrè, Francesco; Donati, Francesco

    2016-08-01

    In this work we present the application of a method for the identification of homologous blood transfusions using forensic genetic techniques based on DNA typing. Ex vivo mixtures of human blood samples - either whole blood or red blood cell concentrates - simulating homologous blood transfusions at different percentages of the donor were typed for a panel of 16 highly variable DNA short tandem repeats (STR). Tested samples included also mixtures, which gave false-negative results if assayed by the reference flow cytofluorimetric method, which is based on the recognition of target antigens located on the membrane of the red blood cell. The recognition of triplets and quadruplets at various loci gave information of the presence of cells belonging to different individuals, as it is the case for homologous blood transfusions. Specificity and sensitivity of the method were assessed in the validation study. The method proved to be unequivocally specific since it was able to recognize all single profiles of each individual, clearly discriminating them from mixtures. Sensitivity resulted as a consequence of the percentage of the donor aliquot in the total volume of the mixture. Although the source of DNA in a blood sample is represented only by nucleated white blood cells, the same procedure resulted effective also in detecting mixtures of red blood cell concentrates (RBCC) from leukodepletion procedure: DNA of the donor from the residual white blood cells resulted still detectable, even if with an expected loss of sensitivity. The proposed approach may contribute to reduce the risk of false-negative results, which may occur using the reference cytofluorimetric method. PMID:27175858

  10. Glucose 6-phosphate dehydrogenase deficient subjects may be better "storers" than donors of red blood cells.

    PubMed

    Tzounakas, Vassilis L; Kriebardis, Anastasios G; Georgatzakou, Hara T; Foudoulaki-Paparizos, Leontini E; Dzieciatkowska, Monika; Wither, Matthew J; Nemkov, Travis; Hansen, Kirk C; Papassideri, Issidora S; D'Alessandro, Angelo; Antonelou, Marianna H

    2016-07-01

    Storage of packed red blood cells (RBCs) is associated with progressive accumulation of lesions, mostly triggered by energy and oxidative stresses, which potentially compromise the effectiveness of the transfusion therapy. Concerns arise as to whether glucose 6-phosphate dehydrogenase deficient subjects (G6PD(-)), ~5% of the population in the Mediterranean area, should be accepted as routine donors in the light of the increased oxidative stress their RBCs suffer from. To address this question, we first performed morphology (scanning electron microscopy), physiology and omics (proteomics and metabolomics) analyses on stored RBCs from healthy or G6PD(-) donors. We then used an in vitro model of transfusion to simulate transfusion outcomes involving G6PD(-) donors or recipients, by reconstituting G6PD(-) stored or fresh blood with fresh or stored blood from healthy volunteers, respectively, at body temperature. We found that G6PD(-) cells store well in relation to energy, calcium and morphology related parameters, though at the expenses of a compromised anti-oxidant system. Additional stimuli, mimicking post-transfusion conditions (37°C, reconstitution with fresh healthy blood, incubation with oxidants) promoted hemolysis and oxidative lesions in stored G6PD(-) cells in comparison to controls. On the other hand, stored healthy RBC units showed better oxidative parameters and lower removal signaling when reconstituted with G6PD(-) fresh blood compared to control. Although the measured parameters of stored RBCs from the G6PD deficient donors appeared to be acceptable, the results from the in vitro model of transfusion suggest that G6PD(-) RBCs could be more susceptible to hemolysis and oxidative stresses post-transfusion. On the other hand, their chronic exposure to oxidative stress might make them good recipients, as they better tolerate exposure to oxidatively damaged long stored healthy RBCs. PMID:27094493

  11. Hyperventilation and blood acid-base balance in hypercapnia exposed red drum (Sciaenops ocellatus).

    PubMed

    Ern, Rasmus; Esbaugh, Andrew J

    2016-05-01

    Hyperventilation is a common response in fish exposed to elevated water CO2. It is believed to lessen the respiratory acidosis associated with hypercapnia by lowering arterial PCO2, but the contribution of hyperventilation to blood acid-base compensation has yet to be quantified. Hyperventilation may also increase the flux of irons across the gill epithelium and the cost of osmoregulation, owing to the osmo-respiratory compromise. Therefore, hypercapnia exposed fish may increase standard metabolic rate (SMR) leaving less energy for physiological functions such as foraging, migration, growth and reproduction. Here we show that gill ventilation, blood PCO2 and total blood [CO2] increased in red drum (Sciaenops ocellatus) exposed to 1000 and 5000 µatm water CO2, and that blood PCO2 and total blood [CO2] decrease in fish during hypoxia induced hyperventilation. Based on these results we estimate the ventilatory contributions to total acid-base compensation in 1000 and 5000 µatm water CO2. We find that S. ocellatus only utilize a portion of its ventilatory capacity to reduce the acid-base disturbance in 1000 µatm water CO2. SMR was unaffected by both salinity and hypercapnia exposure indicating that the cost of osmoregulation is small relative to SMR, and that the lack of increased ventilation in 1000 µatm water CO2 despite the capacity to do so is not due to an energetic tradeoff between acid-base balance and osmoregulation. Therefore, while ocean acidification may impact ventilatory parameters, there will be little impact on the overall energy budget of S. ocellatus. PMID:26922790

  12. Magnetic red blood cells as new contrast agents for MRI applications

    NASA Astrophysics Data System (ADS)

    Antonelli, Antonella; Sfara, Carla; Manuali, Elisabetta; Salamida, Sonia; Louin, Gaëlle; Magnani, Mauro

    2013-03-01

    Superparamagnetic iron oxide (SPIO) nanoparticles have been produced and used successfully as potent contrast agents for Magnetic Resonance Imaging (MRI). However, a significant challenge associated with the biological application of SPIO-tracer agents is their behavior in vivo since their efficacy is often compromised due to a rapid recognition and clearance by the reticuloendothelial system (RES) which limits the applicability of such compounds in MRI. The advances in nanotechnology and molecular cell biology had lead to improve stability and biocompatibility of these nanoparticles, but despite a number of efforts, the SPIO half-life in blood circulation is very short. In this contest, the potential of red blood cells (RBCs) loaded with SPIO nanoparticles as a tracer material for MRI has been investigated in order to realize a blood pool tracer with longer blood retention time. Previously, we have proposed the encapsulation into RBCs of superparamagnetic iron oxide nanoparticles carboxydextran coated, such as Resovist contrast agent. This approach led to a nanoparticle reduction in uptake by the RES, increasing the blood circulation half-life of nanoparticles. Recently, the loading procedure was applied to a new contrast agent, the P904 ultrasmall superparamagnetic iron oxide (USPIO) nanoparticles coated by hydrophilic derivatives of glucose, recently developed by Guerbet Laboratories. The results evidenced that this nanomaterial can be efficiently loaded into human and murine RBCs at concentrations ranging from 1.5 to 12 mM Fe. In vivo experiments performed in mice have showed an increased survival in the mouse vascular system of P904 encapsulated into RBCs respect to free P904 sample intravenously injected at the equivalent amounts.

  13. Blood serum and BSA, but neither red blood cells nor hemoglobin can support vitellogenesis and egg production in the dengue vector Aedes aegypti

    PubMed Central

    Gonzales, Kristina K.; Tsujimoto, Hitoshi

    2015-01-01

    Aedes aegypti is the major vector of dengue, yellow fever and chikungunya viruses that put millions of people in endemic countries at risk. Mass rearing of this mosquito is crucial for strategies that use modified insects to reduce vector populations and transmission of pathogens, such as sterile insect technique or population replacement. A major problem for vector mosquito mass rearing is the requirement of vertebrate blood for egg production since it poses significant costs as well as potential health hazards. Also, regulations for human and animal use as blood source can pose a significant obstacle. A completely artificial diet that supports egg production in vector mosquitoes can solve this problem. In this study, we compared different blood fractions, serum and red blood cells, as dietary protein sources for mosquito egg production. We also tested artificial diets made from commercially available blood proteins (bovine serum albumin (BSA) and hemoglobin). We found that Ae. aegypti performed vitellogenesis and produced eggs when given whole bovine blood, serum, or an artificial diet containing BSA. Conversely, egg production was impaired after feeding of the red blood cell fraction or an artificial diet containing only hemoglobin. We also found that egg viability of serum-fed mosquitoes were comparable to that of whole blood and an iron supplemented BSA meal produced more viable eggs than a meal containing BSA alone. Our results indicate that serum proteins, not hemoglobin, may replace vertebrate blood in artificial diets for mass mosquito rearing. PMID:26020000

  14. Blood serum and BSA, but neither red blood cells nor hemoglobin can support vitellogenesis and egg production in the dengue vector Aedes aegypti.

    PubMed

    Gonzales, Kristina K; Tsujimoto, Hitoshi; Hansen, Immo A

    2015-01-01

    Aedes aegypti is the major vector of dengue, yellow fever and chikungunya viruses that put millions of people in endemic countries at risk. Mass rearing of this mosquito is crucial for strategies that use modified insects to reduce vector populations and transmission of pathogens, such as sterile insect technique or population replacement. A major problem for vector mosquito mass rearing is the requirement of vertebrate blood for egg production since it poses significant costs as well as potential health hazards. Also, regulations for human and animal use as blood source can pose a significant obstacle. A completely artificial diet that supports egg production in vector mosquitoes can solve this problem. In this study, we compared different blood fractions, serum and red blood cells, as dietary protein sources for mosquito egg production. We also tested artificial diets made from commercially available blood proteins (bovine serum albumin (BSA) and hemoglobin). We found that Ae. aegypti performed vitellogenesis and produced eggs when given whole bovine blood, serum, or an artificial diet containing BSA. Conversely, egg production was impaired after feeding of the red blood cell fraction or an artificial diet containing only hemoglobin. We also found that egg viability of serum-fed mosquitoes were comparable to that of whole blood and an iron supplemented BSA meal produced more viable eggs than a meal containing BSA alone. Our results indicate that serum proteins, not hemoglobin, may replace vertebrate blood in artificial diets for mass mosquito rearing. PMID:26020000

  15. Microfluidic interactions between red blood cells and drug carriers by image analysis techniques.

    PubMed

    D'Apolito, Rosa; Taraballi, Francesca; Minardi, Silvia; Liu, Xuewu; Caserta, Sergio; Cevenini, Armando; Tasciotti, Ennio; Tomaiuolo, Giovanna; Guido, Stefano

    2016-01-01

    Blood is a complex biological fluid composed of deformable cells and platelets suspended in plasma, a protein-rich liquid. The peculiar nature of blood needs to be considered when designing a drug delivery strategy based on systemically administered carriers. Here, we report on an in vitro fluid dynamic investigation of the influence of the microcapillary flow of red blood cells (RBCs) on micron-sized carriers by high-speed imaging methods. The experiments were carried out in a 50 µm diameter glass capillary that mimicked the hydrodynamic conditions of human microcirculation. Spherical μ-particles (μ-Ps), with sizes ranging between 0.5 and 3 µm, were tested. Images of the flowing RBCs and μ-Ps were acquired by a high- speed/high-magnification microscopy. The transport and distribution of rigid particles in a suspension of RBCs under shear flow were investigated by analyzing: (i) the velocity profile of both μ-Ps and RBCs in the capillary; (ii) the radial distribution of μ-Ps in the presence of RBCs; (iii) the migration of μ-Ps towards the vessel wall due to their hydrodynamic interactions with RBCs. This study suggests that the therapeutic efficacy of μ-Ps could be ultimately affected by their interactions with the flowing RBCs in the vasculature. PMID:26651215

  16. Investigation of diseases through red blood cells' shape using photoacoustic response technique

    NASA Astrophysics Data System (ADS)

    Biswas, Deblina; Gorey, Abhijeet; Chen, Goerge C. K.; Sharma, Norman; Vasudevan, Srivathsan

    2015-03-01

    Photoacoustic (PA) imaging is a non-invasive real-time technique, widely applied to many biomedical imaging studies in the recent years. While most of these studies have been focussed on obtaining an image after reconstruction, various features of time domain signal (e.g. amplitude, width, rise and relaxation time) would provide very high sensitivity in detecting morphological changes in cells during a biological study. Different haematological disorders (e.g., sickle cell anaemia, thalassemia) exhibit significant morphological cellular changes. In this context, this study explores the possibility of utilizing the developed photoacoustic response technique to apply onto blood samples. Results of our preliminary study demonstrate that there is a significant change in signal amplitude due to change in concentration of the blood. Thus it shows the sensitivity of the developed photoacoustic technique towards red blood cell count (related to haematological disease like anaemia). Subsequently, morphological changes in RBC (i.e. swollen and shrunk compared to normal RBC) induced by hypotonic and hypertonic solutions respectively were also experimented. The result shows a distinct change in PA signal amplitude. This would serve as a diagnostic signature for many future studies on cellular morphological disorders.

  17. Red blood cell abnormalities and the pathogenesis of anemia in end-stage renal disease.

    PubMed

    Georgatzakou, Hara T; Antonelou, Marianna H; Papassideri, Issidora S; Kriebardis, Anastasios G

    2016-08-01

    Anemia is the most common hematologic complication in end-stage renal disease (ESRD). It is ascribed to decreased erythropoietin production, shortened red blood cell (RBC) lifespan, and inflammation. Uremic toxins severely affect RBC lifespan; however, the implicated molecular pathways are poorly understood. Moreover, current management of anemia in ESRD is controversial due to the "anemia paradox" phenomenon, which underlines the need for a more individualized approach to therapy. RBCs imprint the adverse effects of uremic, inflammatory, and oxidative stresses in a context of structural and functional deterioration that is associated with RBC removal signaling and morbidity risk. RBCs circulate in hostile plasma by raising elegant homeostatic defenses. Variability in primary defect, co-morbidity, and therapeutic approaches add complexity to the pathophysiological background of the anemic ESRD patient. Several blood components have been suggested as biomarkers of anemia-related morbidity and mortality risk in ESRD. However, a holistic view of blood cell and plasma modifications through integrated omics approaches and high-throughput studies might assist the development of new diagnostic tests and therapies that will target the underlying pathophysiologic processes of ESRD anemia. PMID:26948278

  18. Nitric oxide influences red blood cell velocity independently of changes in the vascular tone.

    PubMed

    Horn, Patrick; Cortese-Krott, Miriam M; Keymel, Stefanie; Kumara, Intan; Burghoff, Sandra; Schrader, Jürgen; Kelm, Malte; Kleinbongard, Petra

    2011-06-01

    Nitric oxide (NO) plays a key role in regulation of vascular tone and blood flow. In the microcirculation blood flow is strongly dependent on red blood cells (RBC) deformability. In vitro NO increases RBC deformability. This study hypothesized that NO increases RBC velocity in vivo not only by regulating vascular tone, but also by modifying RBC deformability. The effects of NO on RBC velocity were analysed by intra-vital microscopy in the microcirculation of the chorioallantoic membrane (CAM) of the avian embryo at day 7 post-fertilization, when all vessels lack smooth muscle cells and vascular tone is not affected by NO. It was found that inhibition of enzymatic NO synthesis and NO scavenging decreased intracellular NO levels and avian RBC deformability in vitro. Injection of a NO synthase-inhibitor or a NO scavenger into the microcirculation of the CAM decreased capillary RBC velocity and deformation, while the diameter of the vessels remained constant. The results indicate that scavenging of NO and inhibition of NO synthesis decrease RBC velocity not only by regulating vascular tone but also by decreasing RBC deformability. PMID:21480762

  19. Variation of red blood cell distribution width and mean platelet volume after moderate endurance exercise.

    PubMed

    Lippi, Giuseppe; Salvagno, Gian Luca; Danese, Elisa; Tarperi, Cantor; Guidi, Gian Cesare; Schena, Federico

    2014-01-01

    Although physical exercise strongly influences several laboratory parameters, data about the hematological changes after medium distance running are scarce. We studied 31 middle-trained athletes (mean training regimen 217 ± 32 min/week) who performed a 21.1 km, half-marathon run. Blood samples were collected before the run, at the end, and 3 and 20 hours thereafter. The complete blood count was performed on Advia 2120 and included red blood cell (RBC), reticulocyte, and platelet counts; hemoglobin; mean corpuscular volume (MCV); mean corpuscular hemoglobin (MCH); reticulocyte haemoglobin content (Ret CHR); RBC distribution width (RDW), mean platelet volume (MPV). No significant variations were observed for MCH and Ret CHR. The RBC, reticulocyte, and hemoglobin values modestly decreased after the run. The MCV significantly increased at the end of running but returned to baseline 3 hours thereafter. The RDW constantly increased, reaching a peak 20 hours after the run. The platelet count and MPV both increased after the run and returned to baseline 3 hours thereafter. These results may have implications for definition of reference ranges and antidoping testing, and may also contribute to explaining the relationship between endurance exercise and mortality, since previous studies reported that RDW and MPV may be significantly associated with cardiovascular disease. PMID:25197280

  20. First clues to understand red blood cell interactions: numerical studies of vesicle suspensions

    NASA Astrophysics Data System (ADS)

    Thiébaud, Marine; Misbah, Chaouqi; Dyfcom Team

    2014-03-01

    The scientific community started raising questions on blood flow for nearly two centuries, a period traced back to the pioneering work of Poiseuille. This topic has known a considerable upsurge of interest during the past decade. Vesicles capture several essential features shared with red blood cells. A single vesicle is now fairly understood, whereas study of suspensions is still unclear. We conduct bidimensionnal numerical studies by mean of the boundary integral method. Confinement plays a major role in that it introduces an interaction cut-off length. I will present results on the behavior of relative viscosity as function of the viscosity contrast between the fluid encapsulated by vesicles and the ambient fluid. This viscosity contrast is a key parameter: it triggers transition from tank-treading to tumbling regimes. Historical characterization of blood have led to the discovery of the Fahraeus-Lindqvist effect. I will introduce some results on this effect with a rheological study as function of concentration and confinement. I will report on non-standard behavior induced by a subtle spatio-temporal organization of the suspension. We would like to thank CNES for financial support.

  1. Indolic Uremic Solutes Enhance Procoagulant Activity of Red Blood Cells through Phosphatidylserine Exposure and Microparticle Release

    PubMed Central

    Gao, Chunyan; Ji, Shuting; Dong, Weijun; Qi, Yushan; Song, Wen; Cui, Debin; Shi, Jialan

    2015-01-01

    Increased accumulation of indolic uremic solutes in the blood of uremic patients contributes to the risk of thrombotic events. Red blood cells (RBCs), the most abundant blood cells in circulation, may be a privileged target of these solutes. However, the effect of uremic solutes indoxyl sulfate (IS) and indole-3-acetic acid (IAA) on procoagulant activity (PCA) of erythrocyte is unclear. Here, RBCs from healthy adults were treated with IS and IAA (mean and maximal concentrations reported in uremic patients). Phosphatidylserine (PS) exposure of RBCs and their microparticles (MPs) release were labeled with Alexa Fluor 488-lactadherin and detected by flow cytometer. Cytosolic Ca2+ ([Ca2+]) with Fluo 3/AM was analyzed by flow cytometer. PCA was assessed by clotting time and purified coagulation complex assays. We found that PS exposure, MPs generation, and consequent PCA of RBCs at mean concentrations of IS and IAA enhanced and peaked in maximal uremic concentrations. Moreover, 128 nM lactadherin, a PS inhibitor, inhibited over 90% PCA of RBCs and RMPs. Eryptosis or damage, by indolic uremic solutes was due to, at least partially, the increase of cytosolic [Ca2+]. Our results suggest that RBC eryptosis in uremic solutes IS and IAA plays an important role in thrombus formation through releasing RMPs and exposing PS. Lactadherin acts as an efficient anticoagulant in this process. PMID:26516916

  2. Red blood cell membrane camouflaged magnetic nanoclusters for imaging-guided photothermal therapy.

    PubMed

    Ren, Xiaoqing; Zheng, Rui; Fang, Xiaoling; Wang, Xiaofei; Zhang, Xiaoyan; Yang, Wuli; Sha, Xianyi

    2016-06-01

    Along with intrinsic magnetic resonance imaging (MRI) advantages, iron oxide nanomaterials capable of photothermal conversion have been reported very recently and have again raised great interest in their designs among biomedical researchers. However, like other inorganic nanomaterials, high macrophage uptake, short blood retention time and unfavorable biodistributions have strongly hampered their applications in vivo. To solve these problems, a rational design of red blood cell (RBC) membrane camouflaged iron oxide magnetic clusters (MNC@RBCs) is presented in this paper. Our data show that by simply introducing an "ultra-stealth" biomimetic coating to iron oxide magnetic nanoclusters (MNCs), MNC@RBCs maintain the imaging and photothermal functionalities inherited from MNCs cores while achieving much lower nonspecific macrophage uptake and dramatically altered fate in vivo. MNC@RBCs with superior prolonged blood retention time, preferred high tumor accumulation and relatively lowered liver biodistribution are demonstrated when injected intravenously in mice, leading to greatly enhanced photothermal therapeutic efficacy by a single treatment without further magnetic force manipulation. Our study illustrates a well prepared integration of MNCs and RBCs, exploiting advantages of both functionalities within a single unit and suggests a promising future for iron-based nanomaterials application in vivo. PMID:27031929

  3. Indolic uremic solutes enhance procoagulant activity of red blood cells through phosphatidylserine exposure and microparticle release.

    PubMed

    Gao, Chunyan; Ji, Shuting; Dong, Weijun; Qi, Yushan; Song, Wen; Cui, Debin; Shi, Jialan

    2015-11-01

    Increased accumulation of indolic uremic solutes in the blood of uremic patients contributes to the risk of thrombotic events. Red blood cells (RBCs), the most abundant blood cells in circulation, may be a privileged target of these solutes. However, the effect of uremic solutes indoxyl sulfate (IS) and indole-3-acetic acid (IAA) on procoagulant activity (PCA) of erythrocyte is unclear. Here, RBCs from healthy adults were treated with IS and IAA (mean and maximal concentrations reported in uremic patients). Phosphatidylserine (PS) exposure of RBCs and their microparticles (MPs) release were labeled with Alexa Fluor 488-lactadherin and detected by flow cytometer. Cytosolic Ca(2+) ([Ca(2+)]) with Fluo 3/AM was analyzed by flow cytometer. PCA was assessed by clotting time and purified coagulation complex assays. We found that PS exposure, MPs generation, and consequent PCA of RBCs at mean concentrations of IS and IAA enhanced and peaked in maximal uremic concentrations. Moreover, 128 nM lactadherin, a PS inhibitor, inhibited over 90% PCA of RBCs and RMPs. Eryptosis or damage, by indolic uremic solutes was due to, at least partially, the increase of cytosolic [Ca(2+)]. Our results suggest that RBC eryptosis in uremic solutes IS and IAA plays an important role in thrombus formation through releasing RMPs and exposing PS. Lactadherin acts as an efficient anticoagulant in this process. PMID:26516916

  4. An extended convection diffusion model for red blood cell-enhanced transport of thrombocytes and leukocytes

    NASA Astrophysics Data System (ADS)

    Hund, S. J.; Antaki, J. F.

    2009-10-01

    Transport phenomena of platelets and white blood cells (WBCs) are fundamental to the processes of vascular disease and thrombosis. Unfortunately, the dilute volume occupied by these cells is not amenable to fluid-continuum modeling, and yet the cell count is large enough that modeling each individual cell is impractical for most applications. The most feasible option is to treat them as dilute species governed by convection and diffusion; however, this is further complicated by the role of the red blood cell (RBC) phase on the transport of these cells. We therefore propose an extended convection-diffusion (ECD) model based on the diffusive balance of a fictitious field potential, Ψ, that accounts for the gradients of both the dilute phase and the local hematocrit. The ECD model was applied to the flow of blood in a tube and between parallel plates in which a profile for the RBC concentration field was imposed and the resulting platelet concentration field predicted. Compared to prevailing enhanced-diffusion models that dispersed the platelet concentration field, the ECD model was able to simulate a near-wall platelet excess, as observed experimentally. The extension of the ECD model depends only on the ability to prescribe the hematocrit distribution, and therefore may be applied to a wide variety of geometries to investigate platelet-mediated vascular disease and device-related thrombosis.

  5. Evaluation of red blood cell aggregation in diabetes by computerized image analysis.

    PubMed

    Foresto, P; D'Arrigo, M; Carreras, L; Cuezzo, R E; Valverde, J; Rasia, R

    2000-01-01

    Red blood cell (RBC) aggregation has been widely studied and its importance is well established in the rheology of microcirculation. RBC aggregation is a major factor responsible for the flow properties of blood. Increased RBC aggregation has been observed in several pathological states. Therefore, the measurement of erythrocyte aggregation is rheologically important for quantifying flow abnormality in pathological conditions. Normal RBC under low flow or at rest form rouleaux aggregates, while abnormal RBC aggregation may lead to the formation of irregular aggregate structures, which may be induced by cell-associated factors (reduced membrane sialic acid levels) but also by extracellular factors. The main objective of the present investigation was to study RBC aggregate morphology in diabetic patients, using direct microscopic observation and numerical processing of recorded digitized images. Blood samples were obtained from 20 diabetic patients and from 15 normal control subjects. The aggregate morphology was quantified by the so-called Aggregate Shape Parameter (ASP) defined as the ratio of the aggregate projected area to its square perimeter. ASP appeared significantly higher (p < 10(-5)) in diabetic patients (0.65 +/- 0.18) than in normal controls (0.28 +/- 0.15). This rheo-optical method based on the theoretical model for rouleaux aggregates provides a useful reference for measuring deviations of RBC aggregate morphology. Increased aggregation of RBC resulting from a decreased sialylation of glycophorins may be an important factor in the development of vascular diseases and in the microcirculation impairment. PMID:11188894

  6. A study of red blood cell deformability in diabetic retinopathy using optical tweezers

    NASA Astrophysics Data System (ADS)

    Smart, Thomas J.; Richards, Christopher J.; Bhatnagar, Rhythm; Pavesio, Carlos; Agrawal, Rupesh; Jones, Philip H.

    2015-08-01

    Diabetic retinopathy (DR) is a microvascular complication of diabetes mellitus (DM) in which high blood sugar levels cause swelling, leaking and occlusions in the blood vessels of the retina, often resulting in a loss of sight. The microvascular system requires red blood cells (RBCs) to undergo significant cellular deformation in order to pass through vessels whose diameters are significantly smaller than their own. There is evidence to suggest that DM impairs the deformability of RBCs, and this loss of deformability has been associated with diabetic kidney disease (or nephropathy) - another microvascular complication of DM. However, it remains unclear whether reduced deformability of RBCs correlates with the presence of DR. Here we present an investigation into the deformability of RBCs in patients with diabetic retinopathy using optical tweezers. To extract a value for the deformability of RBCs we use a dual-trap optical tweezers set-up to stretch individual RBCs. RBCs are trapped directly (i.e. without micro-bead handles), so rotate to assume a `side-on' orientation. Video microscopy is used to record the deformation events, and shape analysis software is used to determine parameters such as initial and maximum RBC length, allowing us to calculate the deformability for each RBC. A small decrease in deformability of diabetes cells subject to this stretching protocol is observed when compared to control cells. We also report on initial results on three dimensional imaging of individual RBCs using defocussing microscopy.

  7. Flow of a circulating tumor cell and red blood cells in microvessels

    NASA Astrophysics Data System (ADS)

    Takeishi, Naoki; Imai, Yohsuke; Yamaguchi, Takami; Ishikawa, Takuji

    2015-12-01

    Quantifying the behavior of circulating tumor cells (CTCs) in the blood stream is of fundamental importance for understanding metastasis. Here, we investigate the flow mode and velocity of CTCs interacting with red blood cells (RBCs) in various sized microvessels. The flow of leukocytes in microvessels has been described previously; a leukocyte forms a train with RBCs in small microvessels and exhibits margination in large microvessels. Important differences in the physical properties of leukocytes and CTCs result from size. The dimensions of leukocytes are similar to those of RBCs, but CTCs are significantly larger. We investigate numerically the size effects on the flow mode and the cell velocity, and we identify similarities and differences between leukocytes and CTCs. We find that a transition from train formation to margination occurs when (R -a ) /tR≈1 , where R is the vessel radius, a is the cell radius, and tR is the thickness of RBCs, but that the motion of RBCs differs from the case of leukocytes. Our results also show that the velocities of CTCs and leukocytes are larger than the average blood velocity, but only CTCs move faster than RBCs for microvessels of R /a ≈1.5 -2.0 . These findings are expected to be useful not only for understanding metastasis, but also for developing microfluidic devices.

  8. Effect of Model Type on the Accuracy of Polarization and Nephelometric Measurements of Red-Blood-Cell Volume

    NASA Astrophysics Data System (ADS)

    Kugeiko, M. M.; Smunev, D. A.

    2016-05-01

    The effect of using different mathematical models of a red blood cell on the accuracy of the measured average volume for a population of red blood cells was evaluated. The accuracy was estimated based on regression equations between the retrieved microphysical and measured optical properties. Models of a sphere, oblate spheroid, and biconcave discoid represented as a disc with rounded edges and concavities in the middle were analyzed. It was shown that the error of the regression equations when determining the average red-blood-cell volume using the biconcave discoid model was 1%; spheroid, ~8%; and sphere, ~21%. The error of the average volume due to the model is a few percent for the spheroid and ~20% for the sphere.

  9. A Lattice Boltzmann Fictitious Domain Method for Modeling Red Blood Cell Deformation and Multiple-Cell Hydrodynamic Interactions in Flow

    SciTech Connect

    Shi, Xing; Lin, Guang; Zou, Jianfeng; Fedosov, Dmitry A.

    2013-07-20

    To model red blood cell (RBC) deformation in flow, the recently developed LBM-DLM/FD method ([Shi and Lim, 2007)29], derived from the lattice Boltzmann method and the distributed Lagrange multiplier/fictitious domain methodthe fictitious domain method, is extended to employ the mesoscopic network model for simulations of red blood cell deformation. The flow is simulated by the lattice Boltzmann method with an external force, while the network model is used for modeling red blood cell deformation and the fluid-RBC interaction is enforced by the Lagrange multiplier. To validate parameters of the RBC network model, sThe stretching numerical tests on both coarse and fine meshes are performed and compared with the corresponding experimental data to validate the parameters of the RBC network model. In addition, RBC deformation in pipe flow and in shear flow is simulated, revealing the capacity of the current method for modeling RBC deformation in various flows.

  10. LETTER TO THE EDITOR: Arterio-venous flow between monochorionic twins determined during intra-uterine transfusion. Nonlinear decay of adult red blood cells

    NASA Astrophysics Data System (ADS)

    van Gemert, Martin J. C.; Pasman, Suzanne A.; van den Wijngaard, Jeroen P. H. M.; Lopriore, Enrico; Vandenbussche, Frank P. H. A.

    2008-07-01

    Recently, we derived equations relating the flow of adult red blood cells through a placental arterio-venous anastomosis with intra-uterine and post-natal measured adult hemoglobin concentrations. In this letter, we re-derived the equations, now including a more realistic nonlinear decay of adult red blood cells, and re-evaluated the measurement accuracy of the arterio-venous flow and the lifetime of the red blood cells.

  11. Three-dimensional refractive index tomograms and deformability of individual human red blood cells from cord blood of newborn infants and maternal blood

    NASA Astrophysics Data System (ADS)

    Park, HyunJoo; Ahn, Taegyu; Kim, Kyoohyun; Lee, Sangyun; Kook, Song-yi; Lee, Dongheon; Suh, In Bum; Na, Sunghun; Park, YongKeun

    2015-11-01

    Red blood cells (RBCs) from the cord blood of newborn infants have distinctive functions in fetal and infant development. To systematically investigate the biophysical characteristics of individual cord RBCs in newborn infants, a comparative study was performed on RBCs from the cord blood of newborn infants and from adult mothers or nonpregnant women using optical holographic microtomography. Optical measurements of the distributions of the three-dimensional refractive indices and the dynamic membrane fluctuations of individual RBCs were used to investigate the morphological, biochemical, and mechanical properties of cord, maternal, and adult RBCs at the individual cell level. The volume and surface area of the cord RBCs were significantly larger than those of the RBCs from nonpregnant women, and the cord RBCs had more flattened shapes than that of the RBCs in adults. In addition, the hemoglobin (Hb) content in the cord RBCs from newborns was significantly higher. The Hb concentration in the cord RBCs was higher than that in the nonpregnant women or maternal RBCs, but they were within the physiological range of adults. Interestingly, the amplitudes of the dynamic membrane fluctuations in cord RBCs were comparable to those in nonpregnant women and maternal RBCs, suggesting that the deformability of cord RBCs is similar to that of healthy RBCs in adults.

  12. Three-dimensional refractive index tomograms and deformability of individual human red blood cells from cord blood of newborn infants and maternal blood.

    PubMed

    Park, HyunJoo; Ahn, Taegyu; Kim, Kyoohyun; Lee, Sangyun; Kook, Song-Yi; Lee, Dongheon; Suh, In Bum; Na, Sunghun; Park, YongKeun

    2015-01-01

    Red blood cells (RBCs) from the cord blood of newborn infants have distinctive functions in fetal and infant development. To systematically investigate the biophysical characteristics of individual cord RBCs in newborn infants, a comparative study was performed on RBCs from the cord blood of newborn infants and from adult mothers or nonpregnant women using optical holographic microtomography. Optical measurements of the distributions of the three-dimensional refractive indices and the dynamic membrane fluctuations of individual RBCs were used to investigate the morphological, biochemical, and mechanical properties of cord, maternal, and adult RBCs at the individual cell level. The volume and surface area of the cord RBCs were significantly larger than those of the RBCs from nonpregnant women, and the cord RBCs had more flattened shapes than that of the RBCs in adults. In addition, the hemoglobin (Hb) content in the cord RBCs from newborns was significantly higher. The Hb concentration in the cord RBCs was higher than that in the nonpregnant women or maternal RBCs, but they were within the physiological range of adults. Interestingly, the amplitudes of the dynamic membrane fluctuations in cord RBCs were comparable to those in nonpregnant women and maternal RBCs, suggesting that the deformability of cord RBCs is similar to that of healthy RBCs in adults. PMID:26259511

  13. IgG red blood cell autoantibodies in autoimmune hemolytic anemia bind to epitopes on red blood cell membrane band 3 glycoprotein

    SciTech Connect

    Victoria, E.J.; Pierce, S.W.; Branks, M.J.; Masouredis, S.P. )

    1990-01-01

    Red blood cell (RBC) autoantibodies from patients with IgG warm-type autoimmune hemolytic anemia were labeled with iodine 125 and their RBC binding behavior characterized. Epitope-bearing RBC membrane polypeptides were identified after autoantibody immunoprecipitation of labeled membranes and immunoblotting. Immunoaffinity isolation of labeled membrane proteins with 12 different IgG hemolytic autoantibodies with protein A-agarose revealed a major polypeptide at Mr 95 to 110 kd, which coelectrophoresed on sodium dodecylsulfate-polyacrylamide gel electrophoresis with a membrane component isolated with sheep IgG anti-band 3. Immunoprecipitation studies with chymotrypsinized RBCs resulted in the recovery of two labeled membrane polypeptides with molecular weights characteristically resulting from the chymotryptic fragmentation of band 3. Immunoblotting with sheep IgG anti-band 3 of the immunoprecipitated polypeptides confirmed that hemolytic autoantibody binding led to recovery of band 3 or its fragments. Two 125I-labeled IgG hemolytic autoantibodies showed binding behavior consistent with epitope localization on band 3. The labeled RBC autoantibodies bound immunospecifically to all types of human RBC tested, including those of rare Rh type (Rh-null, D--) at a site density of approximately 10(6) per RBC. The 125I-IgG in two labeled autoantibodies was 84% and 92% adsorbable by human and higher nonhuman primate RBCs. Antigen-negative animal RBC bound less than 10%, consistent with immunospecific RBC binding. IgG-1 was the major subclass in five autoantibodies tested; one of six fixed complement; and autoantibody IgG appeared polyclonal by isoelectric focusing. We conclude that IgG eluted from RBCs of patients with autoimmune hemolytic anemia consists predominantly of a single totally RBC-adsorbable antibody population that binds to antigenic determinants on band 3.

  14. A Prospective Study on Red Blood Cell Transfusion Related Hyperkalemia in Critically Ill Patients

    PubMed Central

    Raza, Shahzad; Ali Baig, Mahadi; Chang, Christopher; Dabas, Ridhima; Akhtar, Mallika; Khan, Areej; Nemani, Krishna; Alani, Rahima; Majumder, Omran; Gazizova, Natalya; Biswas, Shaluk; Patel, Priyeshkumar; Al-Hilli, Jaffar A.; Shad, Yasar; Berger, Barbara J.; Zaman, Mohammad

    2015-01-01

    Background Transfusion-associated hyperkalemic cardiac arrest is a serious complication in patients receiving packed red blood cell (PRBC) transfusions. Mortality from hyperkalemia increases with large volumes of PRBC transfusion, increased rate of transfusion, and the use of stored PRBCs. Theoretically, hyperkalemia may be complicated by low cardiac output, acidosis, hyperglycemia, hypocalcemia, and hypothermia. In this study, we focus on transfusion-related hyperkalemia involving only medical intensive care unit (MICU) patients. Method This prospective observational study focuses on PRBC transfusions among MICU patients greater than 18 years of age. Factors considered during each transfusion included patient’s diagnosis, indication for transfusion, medical co-morbidities, acid-base disorders, K+ levels before and after each PRBC transfusion, age of stored blood, volume and rate of transfusion, and other adverse events. We used Pearson correlation and multivariate analysis for each factor listed above and performed a logistic regression analysis. Results Between June 2011 and December 2011, 125 patients received a total of 160 units of PRBCs. Median age was 63 years (22 - 92 years). Seventy-one (57%) were females. Sixty-three patients (50%) had metabolic acidosis, 75 (60%) had acute renal failure (ARF), and 12 (10%) had end-stage renal disease (ESRD). Indications for transfusion included septic shock (n = 65, 52%), acute blood loss (n = 25, 20%), non-ST elevation myocardial infarction (NSTEMI) (n = 25, 20%) and preparation for procedures (n = 14, 11%). Baseline K+ value was 3.9 ± 1.1 mEq/L compared to 4.3 ± 1.2 mEq/L post-transfusion respectively (P = 0.9). During this study period, 4% of patients developed hyperkalemia (K+ 5.5 mEq/L or above). The mean change of serum potassium in patients receiving transfusion ≥ 12 days old blood was 4.1 ± 0.4 mEq/L compared to 4.8 ± 0.3 mEq/L (mean ± SD) in patients receiving blood 12 days or less old. Sixty

  15. Total haemoglobin mass and red blood cell profile in endurance-trained and non-endurance-trained adolescent athletes.

    PubMed

    Ulrich, Gert; Bärtsch, Peter; Friedmann-Bette, Birgit

    2011-11-01

    To evaluate differences in total haemoglobin mass (tHb mass) and in red blood cell profile between elite endurance-trained (END) and non-endurance-trained (nEND) male and female adolescent athletes, tHb mass (CO rebreathing) and specific variables of red blood cell profile (haemoglobin concentration, haematocrit, erythrocyte indices) were determined in 59 elite junior athletes (29 END, 30 nEND). We hypothesized that at the age of 15-17 years, regular endurance training might induce a significant increase in tHb mass and changes in red blood cell profile. Therefore, all parameters were again determined after 6, 12 and 18 months in a subset of 27 subjects (17 END, 10 nEND). In END, tHb mass related to body weight was ~15% greater than in nEND (11.2 ± 1.6  vs. 9.7 ± 1.3 g kg(-1), P < 0.001), whereas no significant differences were observed for the red blood cell profile. In both groups, tHb mass related to body weight and the variables of red blood cell profile had not changed significantly after 6, 12 and 18 months of regular training. In conclusion, in elite junior athletes, differences in tHb mass between END and nEND were similar, however, smaller compared with previously in adult athletes reported values. At the age of 15-17 years, 18 months of regular training did not induce significant changes in tHb mass beyond alterations explained by physical growth and also variables of red blood cell profile did not change significantly. PMID:21431423

  16. Quantitative phase imaging of human red blood cells using phase-shifting white light interference microscopy with colour fringe analysis

    NASA Astrophysics Data System (ADS)

    Singh Mehta, Dalip; Srivastava, Vishal

    2012-11-01

    We report quantitative phase imaging of human red blood cells (RBCs) using phase-shifting interference microscopy. Five phase-shifted white light interferograms are recorded using colour charge coupled device camera. White light interferograms were decomposed into red, green, and blue colour components. The phase-shifted interferograms of each colour were then processed by phase-shifting analysis and phase maps for red, green, and blue colours were reconstructed. Wavelength dependent refractive index profiles of RBCs were computed from the single set of white light interferogram. The present technique has great potential for non-invasive determination of refractive index variation and morphological features of cells and tissues.

  17. Rheology of dilute suspensions of red blood cells: experimental and theoretical approaches

    NASA Astrophysics Data System (ADS)

    Drochon, A.

    2003-05-01

    Shear viscosity measurements with dilute suspensions of red blood cells are interpreted using a microrheological model that relates the bulk measurements to the physical properties of the suspended cells. It is thus possible to quantify the average deformability of a RBC population in terms of a mean value of the membrane shear elastic modulus E_s. The values obtained for normal cells are in good agreement with those given in the literature. The method allows to discriminate between normal and altered (diamide or glutaraldehyde treated) cells or pathological cells (scleroderma). The predictions of the microrheological model, based on analytic calculations, are also compared with the numerical results of Ramanujan and Pozrikidis (JFM 361, 1998) for dilute suspensions of capsules in simple shear flow.

  18. Full-field velocity imaging of red blood cells in capillaries with spatiotemporal demodulation autocorrelation

    NASA Astrophysics Data System (ADS)

    Wang, Mingyi; Zeng, Yaguang; Dong, Nannan; Liao, Riwei; Yang, Guojian

    2016-03-01

    We propose a full-field optical method for the label-free and quantitative mapping of the velocities of red blood cells (RBCs) in capillaries. It integrates spatiotemporal demodulation and an autocorrelation algorithm, and measures RBC velocity according to the ratio of RBC length to lag time. Conventionally, RBC length is assumed to be a constant and lag time is taken as a variable, while our method treats both of them as variables. We use temporal demodulation and the Butterworth spatial filter to separate RBC signal from background signal, based on which we obtain the RBC length by image segmentation and lag time by autocorrelation analysis. The RBC velocity calculated now is more accurate. The validity of our method is verified by an in vivo experiment on a mouse ear. Owing to its higher image signal-to-noise ratio, our method can be used for mapping RBC velocity in the turbid tissue case.

  19. Monodisperse red blood cell-like particles via consolidation of charged droplets.

    PubMed

    Park, Chul Ho; Chung, Nae-Oh; Lee, Jonghwi

    2011-09-15

    Recently, researchers have tried to produce non-spherical and anisotropic particles to be used in the next generation of multi-functional materials. Of key interest is the red blood cell-like particle. The torus structure was produced under the relatively fast consolidation of monodisperse droplets, and its parameters were found to be tunable by temperature as well as solvent type and concentration. The observation of consolidation demonstrated that the polymers were accumulated and solidified in the torus structure, naturally, whereas there was the critical droplet size to induce the asymmetry diffusivities. The torus structures could be simply tuned by the flow rate and concentration. The coaxial nozzle system produced the core/shell torus particles. These results state that the consolidation mechanism can hold important clues to enhance the range of tuning capabilities. PMID:21719020

  20. Shape quantification of single red blood cells based on their scattering patterns from microscopic images

    NASA Astrophysics Data System (ADS)

    Schneider, Gert; Artmann, Gerhard

    1995-02-01

    The differentiation between discocytic and stomatocytic red blood cell (RBC) shape using conventional microscopic imaging and image analysis tools is still on a very poor level. A procedure to differentiate the degree of stomatocytic shape changes was developed. We obtained multiple microscopic images of the same RBCs settled on a human albumin coated cover slip. The images were acquired when the microscope objective was subsequently focused through the cell layer. At equidistant horizontal planes (z-axis) below, within, and above the microscopic focal plane the light intensity distribution was considered. Using a model based on light refraction, we calculated the intensity distribution of the planes which are out of focus. Using this tool we are able to differentiate RBC shapes precisely. On the other hand, using this model from and the light intensity distributions of different focal planes, we are able to reconstruct the shape of one single RBC located in the optical axis of the microscope.