WorldWideScience

Sample records for lysed red blood

  1. 21 CFR 864.8540 - Red cell lysing reagent.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Red cell lysing reagent. 864.8540 Section 864.8540...) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Reagents § 864.8540 Red cell lysing reagent. (a) Identification. A red cell lysing reagent is a device used to lyse (destroy) red blood cells...

  2. Evidence for the formation of endothelin by lysed red blood cells from endogenous precursor.

    Science.gov (United States)

    Tippler, B; Herbst, C; Simmet, T

    1994-12-12

    The release of endothelin from various blood cell fractions was investigated. Human as well as rat blood cell fractions homogenized by sonification were incubated in buffer for up to 60 min. Neither in platelet nor leukocyte homogenates from either species could immunoreactive endothelin be detected. In contrast, homogenates of red blood cells from both species showed a rapid and time-dependent rise of immunoreactive endothelin levels, reaching a peak at 15 min and decreasing thereafter. However, at time point 0 no immunoreactive endothelin could be detected. Reverse phase high performance liquid chromatography showed immunoreactive endothelin to consist of endothelin-1 as well as big endothelin-1. The release of immunoreactive endothelin in human and rat homogenates was concentration-dependently inhibited by the protease inhibitors, leupeptin, phosphoramidon, chymostatin and pepstatin A in order of increasing potency. Intact red blood cells did not incorporate [125I]endothelin-1 nor did they transform exogenous big endothelin-1 to endothelin-1. However, haemolysis of red blood cells with hypotonic saline (0.2%) or incubation with pore-forming staphylococcal alpha-toxin induced the release of immunoreactive endothelin into the buffer samples. Thus, apart from the indirect vasoconstrictor, haemoglobin, red blood cells can also liberate the direct vasoconstrictor, endothelin, a finding expected to be of considerable pathophysiological significance.

  3. Lyse theses; Lyse teser

    Energy Technology Data Exchange (ETDEWEB)

    Gjelsvik, Martin

    2012-07-01

    The energy sector is undergoing major changes: demand for energy is growing, especially outside Europe in the emerging economies. At the same time the energy production increases pollutants that harm the environment. Despite the construction of more renewable energy, fossil fuels play a dominant role in the years ahead. The owners and the board of Lyse Group has since its establishment in 1999 developed new business areas based on the Group's core competencies. Energy and telecommunications are currently the mainstays of the group, and a growing portion of its revenues from the telecom sector. The historical basis for Lyse has been hydropower production and distribution of electricity in the region - which still make up the bulk of the business. But industry drift has been great: Today Lyse is a major energy company with almost 300 000 paired fiber broadband customers throughout Norway. Lyse owners indicates a long-term industrial perspective, which has provided the opportunity for large investments: Lyse have in 2012 a power grid where 75% is in the ground, a gas network that can accommodate biogas, a district heating network that covers a large area of commercial space and a fiber network covering much of the Stavanger region. Lyse is working to develop new business models. The goal is to create smarter grids and smart home solutions through connection of business areas such as energy and telecommunications. The board of Lyse has asked IRIS develop a set of guiding principles that can provide a platform for strategy development in Lyse. The order from Lyse has not been a desire for the 'politically correct' or scenarios about the future. A thesis can on the contrary be considered as research-based assertion, based on what the research communities and experts believe is 'true' today. The report in its entirety will be available from the 8. of October 2012. (eb)

  4. Red blood cell production

    Science.gov (United States)

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

  5. High Red Blood Cell Count

    Science.gov (United States)

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

  6. Red Blood Cell Antibody Identification

    Science.gov (United States)

    ... ID, RBC; RBC Ab ID Formal name: Red Blood Cell Antibody Identification Related tests: Direct Antiglobulin Test ; RBC ... I should know? How is it used? Red blood cell (RBC) antibody identification is used as a follow- ...

  7. Red blood cell alloimmunization after blood transfusion

    NARCIS (Netherlands)

    Schonewille, Henk

    2008-01-01

    Current pretransfusion policy requires the patients’ serum to be tested for the presence of irregular red blood cell antibodies. In case of an antibody, red blood cells lacking the corresponding antigen are transfused after an antiglobulin crossmatch. The aim of the studies in this thesis is primari

  8. Rare red blood cell abnormalities

    NARCIS (Netherlands)

    van Zwieten, R.

    2015-01-01

    The aim of this thesis is to give insight in the process of diagnosing rare red blood cell defects, to clarify the relation of a defect with cell function and to extend, in this respect, our knowledge about normal red cell function and biochemistry. It is possible to categorize different red cell ab

  9. Red blood cells, spherocytosis (image)

    Science.gov (United States)

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

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

    Science.gov (United States)

    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.

  11. Red blood cells, sickle cell (image)

    Science.gov (United States)

    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.

  12. Infusion of hemolyzed red blood cells within peripheral blood stem cell grafts in patients with and without sickle cell disease.

    Science.gov (United States)

    Fitzhugh, Courtney D; Unno, Hayato; Hathaway, Vincent; Coles, Wynona A; Link, Mary E; Weitzel, R Patrick; Zhao, Xiongce; Wright, Elizabeth C; Stroncek, David F; Kato, Gregory J; Hsieh, Matthew M; Tisdale, John F

    2012-06-14

    Peripheral blood stem cell (PBSC) infusions are associated with complications such as elevated blood pressure and decreased creatinine clearance. Patients with sickle cell disease experience similar manifestations, and some have postulated release of plasma-free hemoglobin with subsequent nitric oxide consumption as causative. We sought to evaluate whether the infusion of PBSC grafts containing lysed red blood cells (RBCs) leads to the toxicity observed in transplant subjects. We report a prospective cohort study of 60 subjects divided into 4 groups based on whether their infusions contained dimethyl sulfoxide (DMSO) and lysed RBCs, no DMSO and fresh RBCs, DMSO and no RBCs, or saline. Our primary end point, change in maximum blood pressure compared with baseline, was not significantly different among groups. Tricuspid regurgitant velocity and creatinine levels also did not differ significantly among groups. Our data do not support free hemoglobin as a significant contributor to toxicity associated with PBSC infusions. This study was registered at clinicaltrials.gov (NCT00631787).

  13. 21 CFR 640.10 - Red Blood Cells.

    Science.gov (United States)

    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 remaining...

  14. Red blood cell decreases of microgravity

    Science.gov (United States)

    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.

  15. Human spleen and red blood cells

    Science.gov (United States)

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

    2016-11-01

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

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

    Science.gov (United States)

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

    2015-07-14

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

  17. Inflight Assay of Red Blood Cell Deformability

    Science.gov (United States)

    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.

  18. Risk of Abnormal Red Blood Cell to Get Malarial Infection

    OpenAIRE

    Viroj Wiwanitkit

    2008-01-01

    Malarial infection in red blood cell disorder is an interesting topic in tropical medicine. In this work, the author proposes a new idea on the physical property of red blood cell and risk for getting malarial infection. The study on scenario of red blood cell disorders is performed. Conclusively, the author found that physical property of red blood cell is an important determinant for getting malarial infection

  19. 21 CFR 660.30 - Reagent Red Blood Cells.

    Science.gov (United States)

    2010-04-01

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

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

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Red blood cell enzyme assay. 864.7100 Section 864...) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Kits and Packages § 864.7100 Red blood cell enzyme assay. (a) Identification. Red blood cell enzyme assay is a device used to measure the activity...

  1. Red blood cells in retinal vascular disorders.

    Science.gov (United States)

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

    2016-01-01

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

  2. Mechanosensing Dynamics of Red blood Cells

    Science.gov (United States)

    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.

  3. Red blood cell clusters in Poiseuille flow

    Science.gov (United States)

    Ghigliotti, Giovanni; Selmi, Hassib; Misbah, Chaouqi; Elasmi, Lassaad

    2011-11-01

    We present 2D numerical simulations of sets of vesicles (closed bags of a lipid bilayer membrane) in a parabolic flow, a setup that mimics red blood cells (RBCs) in the microvasculature. Vesicles, submitted to sole hydrodynamical interactions, are found to form aggregates (clusters) of finite size. The existence of a maximal cluster size is pointed out and characterized as a function of the flow intensity and the swelling ratio of the vesicles. Moreover bigger clusters move at lower velocity, a fact that may prove of physiological interest. These results quantify previous observations of the inhomogeneous distribution of RBCs in vivo (Gaehtgens et al., Blood Cells 6 - 1980). An interpretation of the phenomenon is put forward based on the presence of boli (vortices) between vesicles. Both the results and the explanation can be transposed to the three-dimensional case.

  4. Deep coverage mouse red blood cell proteome: a first comparison with the human red blood cell

    DEFF Research Database (Denmark)

    Pasini, Erica M; Kirkegaard, Morten; Salerno, Doris

    2008-01-01

    Mice have close genetic/physiological relationships to humans, breed rapidly, and can be genetically modified, making them the most used mammal in biomedical research. Because the red blood cell (RBC) is the sole gas transporter in vertebrates, diseases of the RBC are frequently severe; much...

  5. Microfluidic Device for Continuous Magnetophoretic Separation of Red Blood Cells

    CERN Document Server

    Iliescu, Ciprian; Avram, Marioara; Xu, G; Avram, Andrei

    2008-01-01

    This paper presents a microfluidic device for magnetophoretic separation red blood cells from blood under contionous flow. The separation method consist of continous flow of a blood sample (diluted in PBS) through a microfluidic channel which presents on the bottom "dots" of feromagnetic layer. By appling a magnetic field perpendicular on the flowing direction, the feromagnetic "dots" generates a gradient of magnetic field which amplifies the magnetic force. As a result, the red blood cells are captured on the bottom of the microfluidic channel while the rest of the blood is collected at the outlet. Experimental results show that an average of 95 % of red blood cells are trapped in the device

  6. Red blood cell transfusion in septic shock

    DEFF Research Database (Denmark)

    Rosland, Ragnhild G; Hagen, Marte U; Haase, Nicolai

    2014-01-01

    BACKGROUND: Treating anaemia with red blood cell (RBC) transfusion is frequent, but controversial, in patients with septic shock. Therefore we assessed characteristics and outcome associated with RBC transfusion in this group of high risk patients. METHODS: We did a prospective cohort study at 7...... general intensive care units (ICUs) including all adult patients with septic shock in a 5-month period. RESULTS: Ninety-five of the 213 included patients (45%) received median 3 (interquartile range 2-5) RBC units during shock. The median pre-transfusion haemoglobin level was 8.1 (7.4-8.9) g....../dl and independent of shock day and bleeding. Patients with cardiovascular disease were transfused at higher haemoglobin levels. Transfused patients had higher Simplified Acute Physiology Score (SAPS) II (56 (45-69) vs. 48 (37-61), p = 0.0005), more bleeding episodes, lower haemoglobin levels days 1 to 5, higher...

  7. Automated red blood cell analysis compared with routine red blood cell morphology by smear review

    Directory of Open Access Journals (Sweden)

    Dr.Poonam Radadiya

    2015-01-01

    Full Text Available The RBC histogram is an integral part of automated haematology analysis and is now routinely available on all automated cell counters. This histogram and other associated complete blood count (CBC parameters have been found abnormal in various haematological conditions and may provide major clues in the diagnosis and management of significant red cell disorders. Performing manual blood smears is important to ensure the quality of blood count results and to make presumptive diagnosis. In this article we have taken 100 samples for comparative study between RBC histograms obtained by automated haematology analyzer with peripheral blood smear. This article discusses some morphological features of dimorphism and the ensuing characteristic changes in their RBC histograms.

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

    Science.gov (United States)

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

    2015-01-07

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

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

    Directory of Open Access Journals (Sweden)

    Heimo eMairbäurl

    2013-11-01

    Full Text Available 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. 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.

  10. Loading of red blood cells with an analyte-sensitive dye for development of a long-term monitoring technique

    Science.gov (United States)

    Ritter, Sarah C.; Meissner, Kenith E.

    2012-03-01

    Measurement of blood analytes, such as pH and glucose, provide 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). Red blood cells serve as an attractive alternative for carriers of analyte sensors. Once reintroduced to the blood stream, these carriers may continue to live for the remainder of their life span (120 days for humans). They are also biodegradable and biocompatible, thereby eliminating the immune system response common for many implanted devices. The proposed carrier system takes advantage of the ability of the red blood cells to swell in response to a decrease in the osmolarity of the extracellular solution. Just before the membranes lyse, they develop small pores on the scale of tens of nanometers. Analyte-sensitive dyes in the extracellular solution may then diffuse into the perforated red blood cells and become entrapped upon restoration of physiological temperature and osmolarity. Because the membranes contain various analyte transporters, intracellular analyte levels rapidly equilibrate to those of the extracellular solution. A fluorescent dye has been loaded inside of red blood cells using a preswelling technique. Alterations in preparation parameters have been shown to affect characteristics of the resulting dye-loaded red blood cells (e.g., intensity of fluorescence).

  11. Red blood cell vesiculation in hereditary hemolytic anemia

    Science.gov (United States)

    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

  12. Red blood cell vesiculation in hereditary hemolytic anemia

    Directory of Open Access Journals (Sweden)

    Amr eAlaarg

    2013-12-01

    Full Text Available Hereditary hemolytic anemia encompasses a heterogeneous group of anemias characterised 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 asessed. 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

  13. Red blood cell vesiculation in hereditary hemolytic anemia.

    Science.gov (United States)

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

    2013-12-13

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

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

    Science.gov (United States)

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

    2016-08-08

    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.

  15. Control of red blood cell mass during spaceflight

    Science.gov (United States)

    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.

  16. Malaria and human red blood cells.

    Science.gov (United States)

    Mohandas, Narla; An, Xiuli

    2012-11-01

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

  17. [Promising technologies of packed red blood cells production and storage].

    Science.gov (United States)

    Maksimov, A G; Golota, A S; Krassiĭ, A B

    2013-10-01

    The current article is dedicated to promising technologies of packed red blood cells production and storage. The following new technical approaches are presented: (1) erythrocytes storage in strict anaerobic argon-hydrogen environment, (2) lyophilization of erythrocyte suspension by its atomization in nitrogen gas, (3) lyophilization of erythrocytes by directional freezing under the influence of radio frequency radiation, (4) automated pharming of antigen free packed red blood cells from progenitor cell directly at the battlefield.

  18. Mechanisms Linking Red Blood Cell Disorders and Cardiovascular Diseases

    OpenAIRE

    Ioana Mozos

    2015-01-01

    The present paper aims to review the main pathophysiological links between red blood cell disorders and cardiovascular diseases, provides a brief description of the latest studies in this area, and considers implications for clinical practice and therapy. Anemia is associated with a special risk in proatherosclerotic conditions and heart disease and became a new therapeutic target. Guidelines must be updated for the management of patients with red blood cell disorders and cardiovascular dise...

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

    Science.gov (United States)

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

    2017-02-01

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

  20. Computational modeling of red blood cells: A symplectic integration algorithm

    Science.gov (United States)

    Schiller, Ulf D.; Ladd, Anthony J. C.

    2010-03-01

    Red blood cells can undergo shape transformations that impact the rheological properties of blood. Computational models have to account for the deformability and red blood cells are often modeled as elastically deformable objects. We present a symplectic integration algorithm for deformable objects. The surface is represented by a set of marker points obtained by surface triangulation, along with a set of fiber vectors that describe the orientation of the material plane. The various elastic energies are formulated in terms of these variables and the equations of motion are obtained by exact differentiation of a discretized Hamiltonian. The integration algorithm preserves the Hamiltonian structure and leads to highly accurate energy conservation, hence he method is expected to be more stable than conventional finite element methods. We apply the algorithm to simulate the shape dynamics of red blood cells.

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

    CERN Document Server

    Caprio, Di; Higgins, John M; Schonbrun, Ethan

    2015-01-01

    Oxygen is transported throughout the body by hemoglobin in red blood cells. While the oxygen affinity of blood is well understood and is routinely assessed in patients by pulse oximetry, variability at the single-cell level has not been previously measured. In contrast, single-cell measurements of red blood cell volume and hemoglobin concentration are taken millions of times per day by clinical hematology analyzers and 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 hemoglobin concentration for individual red blood cells in high-throughput. We find that the variability in single-cell saturation peaks at an oxygen partial pressure of 2.5%, which corresponds to the maximum slope of the oxygen-hemoglobin dissociation curve. In addition, single-cell oxygen affinity is positively correlated with hemoglobin concentr...

  2. Mechanisms Linking Red Blood Cell Disorders and Cardiovascular Diseases

    Directory of Open Access Journals (Sweden)

    Ioana Mozos

    2015-01-01

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

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

    Science.gov (United States)

    Mozos, Ioana

    2015-01-01

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

  4. RED BLOOD CELL, HEMOGLOBIN AND HEME IN THE PROGRESSION OF ATHEROSCLEROSIS

    Directory of Open Access Journals (Sweden)

    Viktória eJeney

    2014-10-01

    Full Text Available For decades plaque neovascularization was considered as an innocent feature of advanced atherosclerotic lesions, but nowadays growing evidence suggest that this process triggers plaque progression and vulnerability. Neovascularization is induced mostly by hypoxia, but the involvement of oxidative stress is also established. Because of inappropriate angiogenesis, neovessels are leaky and prone to rupture, leading to the extravasation of red blood cells (RBCs within the plaque. RBCs, in the highly oxidative environment of the atherosclerotic lesions, tend to lyse quickly. Both RBC membrane and the released hemoglobin (Hb possess atherogenic activities. Cholesterol content of RBC membrane contributes to lipid deposition and lipid core expansion upon intraplaque hemorrhage. Cell-free Hb is prone to oxidation, and the oxidation products possess pro-oxidant and pro-inflammatory activities. Defense and adaptation mechanisms evolved to cope with the deleterious effects of cell free Hb and heme. These rely on plasma proteins haptoglobin (Hp and hemopexin (Hx with the ability to scavenge and eliminate free Hb and heme form the circulation. The protective strategy is completed with the cellular heme oxygenase-1/ferritin system that becomes activated when Hp and Hx fail to control free Hb and heme-mediated stress. These protective molecules have pharmacological potential in diverse pathologies including atherosclerosis.

  5. Optical tweezers as a new biomedical tool to measure zeta potential of stored red blood cells.

    Directory of Open Access Journals (Sweden)

    Diego C N Silva

    Full Text Available 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.

  6. The homeostasis of Plasmodium falciparum-infected red blood cells.

    Directory of Open Access Journals (Sweden)

    Jakob M A Mauritz

    2009-04-01

    Full Text Available The asexual reproduction cycle of Plasmodium falciparum, the parasite responsible for severe malaria, occurs within red blood cells. A merozoite invades a red cell in the circulation, develops and multiplies, and after about 48 hours ruptures the host cell, releasing 15-32 merozoites ready to invade new red blood cells. During this cycle, the parasite increases the host cell permeability so much that when similar permeabilization was simulated on uninfected red cells, lysis occurred before approximately 48 h. So how could infected cells, with a growing parasite inside, prevent lysis before the parasite has completed its developmental cycle? A mathematical model of the homeostasis of infected red cells suggested that it is the wasteful consumption of host cell hemoglobin that prevents early lysis by the progressive reduction in the colloid-osmotic pressure within the host (the colloid-osmotic hypothesis. However, two critical model predictions, that infected cells would swell to near prelytic sphericity and that the hemoglobin concentration would become progressively reduced, remained controversial. In this paper, we are able for the first time to correlate model predictions with recent experimental data in the literature and explore the fine details of the homeostasis of infected red blood cells during five model-defined periods of parasite development. The conclusions suggest that infected red cells do reach proximity to lytic rupture regardless of their actual volume, thus requiring a progressive reduction in their hemoglobin concentration to prevent premature lysis.

  7. Red and infrared light distribution in blood

    Science.gov (United States)

    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.

  8. Spatial distributions of red blood cells significantly alter local haemodynamics.

    Directory of Open Access Journals (Sweden)

    Joseph M Sherwood

    Full Text Available 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.

  9. Quantification of depletion-induced adhesion of Red Blood Cells

    CERN Document Server

    Steffen, Patrick; Wagner, Christian

    2012-01-01

    Red blood cells (RBC) are known to form aggregates in the forms of rouleaux due to the presence of plasma proteins under physiological conditions. Rouleaux formation can be also induced in vitro by the addition of macromolecules to the RBC solution. Current data on the adhesion strength between red blood cells in their natural discocyte shapes mostly rely on indirect measurements like flow chamber experiments, but on the single cell level data is lacking. Here we present measurements on the dextran induced aggregation of red blood cells by use of atomic force microscopy based single cell force spectroscopy (SCFS). The effects of dextran concentration and molecular weight on the interaction energy of adhering RBCs was determined. The results are in good agreement with a model based on the depletion effect and former experimental studies.

  10. Deep coverage mouse red blood cell proteome: a first comparison with the human red blood cell.

    Science.gov (United States)

    Pasini, Erica M; Kirkegaard, Morten; Salerno, Doris; Mortensen, Peter; Mann, Matthias; Thomas, Alan W

    2008-07-01

    Mice have close genetic/physiological relationships to humans, breed rapidly, and can be genetically modified, making them the most used mammal in biomedical research. Because the red blood cell (RBC) is the sole gas transporter in vertebrates, diseases of the RBC are frequently severe; much research has therefore focused on RBC and cardiovascular disorders of mouse and humans. RBCs also host malaria parasites. Recently we presented an in-depth proteome for the human RBC. Here we present directly comparable data for the mouse RBC as membrane-only, soluble-only, and combined membrane-bound/soluble proteomes (comprising, respectively, 247, 232, and 165 proteins). All proteins were identified, validated, and categorized in terms of subcellular localization, protein family, and function, and in comparison with the human RBC, were classified as orthologs, family-related, or unique. Splice isoforms were identified, and polypeptides migrating with anomalous apparent molecular weights were grouped into putatively ubiquitinated or partially degraded complexes. Overall there was close concordance between mouse and human proteomes, confirming the unexpected RBC complexity. Several novel findings in the human proteome have been confirmed here. This comparison sheds light on several open issues in RBC biology and provides a departure point for more comprehensive understanding of RBC function.

  11. Recharging Red Blood Cell Surface by Hemodialysis

    Directory of Open Access Journals (Sweden)

    Katrin Kliche

    2015-02-01

    Full Text Available Background: Similar as in vascular endothelium the negatively charged glycocalyx of erythrocytes selectively buffers sodium. Loss of glycocalyx (i.e. loss of negative charges leads to increased erythrocyte sodium sensitivity (ESS quantified by a recently developed salt-blood-test (SBT. The hypothesis was tested whether a regular 4-hour hemodialysis (4h-HD alters ESS. Methods: In 38 patients with end stage renal disease (ESRD ESS was measured before and after 4h-HD, together with standard laboratory and clinical parameters (electrolytes, acid-base status, urea, creatinine, hemoglobin, c-reactive protein and blood pressure. Results: Before 4h-HD, 20 patients (out of 38 were classified as “salt sensitive” by SBT. After 4h-HD, this number decreased to 11. Erythrocyte sodium buffering power remained virtually constant in patients with already low ESS before dialysis, whereas in patients with high ESS, 4h-HD improved the initially poor sodium buffering power by about 20%. No significant correlations could be detected between standard blood parameters and the respective ESS values except for plasma sodium concentration which was found increased by 3.1 mM in patients with high salt sensitivity. Conclusions: 4h-HD apparently recharges “run-down” erythrocytes and thus restores erythrocyte sodium buffering capacity. Besides the advantage of efficient sodium buffering in blood, erythrocytes with sufficient amounts of free negative charges at the erythrocyte surface will cause less (mechanical injury to the negatively charged endothelial surface due to efficient repulsive forces between blood and vessel wall. Hemodialysis improves erythrocyte surface properties and thus may prevent early vascular damage in patients suffering from ESRD.

  12. Photoacoustic response of suspended and hemolyzed red blood cells

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  14. In-vitro red blood cell partitioning of doxycycline

    OpenAIRE

    P.V. Deshmukh; Badgujar, P.C.; Gatne, M.M.

    2009-01-01

    Objective: In-vitro red blood cell (RBC) partitioning of doxycycline was studied to determine whether doxycycline penetrates RBC and its concentration was assayed keeping in view its high lipophilicity. Materials and Methods: Standardization of doxycycline was performed in whole blood and plasma of cattle by microbiological assay using Bacillus subtillis ATCC 6633 as indicator organizm. Actual concentration of the drug was obtained by comparing zone inhibition with standard graph and the exte...

  15. Red blood cell and iron metabolism during space flight

    Science.gov (United States)

    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.

  16. The effects of cryopreservation on red blood cell rheologic properties

    NARCIS (Netherlands)

    Henkelman, Sandra; Lagerberg, Johan W. M.; Graaff, Reindert; Rakhorst, Gerhard; van Oeveren, Willem

    2010-01-01

    BACKGROUND: In transfusion medicine, frozen red blood cells (RBCs) are an alternative for liquid-stored RBCs. Little is known about the rheologic properties (i.e., aggregability and deformability) of thawed RBCs. In this study the rheologic properties of high-glycerol frozen RBCs and postthaw stored

  17. Red blood cells intended for transfusion : quality criteria revisited

    NARCIS (Netherlands)

    Hogman, CF; Meryman, HT

    2006-01-01

    Great variation exists with respect to viability and function of fresh and stored red blood cells (RBCs) as well as of the contents of RBC hemoglobin (Hb) in individual units. Improved technology is available for the preparation as well as the storage of RBCs. The authors raise the question whether

  18. Hypoxia, hormones, and red blood cell function in chick embryos.

    Science.gov (United States)

    Dragon, Stefanie; Baumann, Rosemarie

    2003-04-01

    The red blood cell function of avian embryos is regulated by cAMP. Adenosine A(2A) and beta-adrenergic receptor activation during hypoxic conditions cause changes in the hemoglobin oxygen affinity and CO(2) transport. Furthermore, experimental evidence suggests a general involvement of cAMP in terminal differentiation of avian erythroblasts.

  19. Red blood cell transfusion during septic shock in the ICU

    DEFF Research Database (Denmark)

    Perner, A; Smith, S H; Carlsen, S

    2012-01-01

    Transfusion of red blood cells (RBCs) remains controversial in patients with septic shock, but current practice is unknown. Our aim was to evaluate RBC transfusion practice in septic shock in the intensive care unit (ICU), and patient characteristics and outcome associated with RBC transfusion....

  20. Micronuclei in red blood cells of armored catfish Hypostomus ...

    African Journals Online (AJOL)

    SERVER

    2008-04-03

    Apr 3, 2008 ... 1Centro Universitário Metodista - Porto Alegre - RS –Brazil. 2Department of ... 2,000 red blood cells of animals subjected to treatment, it was possible to observe 8.25 ± 0.02% cells .... The social impact of this contamination of.

  1. Challenges for red blood cell biomarker discovery through proteomics

    NARCIS (Netherlands)

    Barasa, B.A.; Slijper, M.

    2014-01-01

    Red blood cells are rather unique body cells, since they have lost all organelles when mature, which results in lack of potential to replace proteins that have lost their function. They maintain only a few pathways for obtaining energy and reducing power for the key functions they need to fulfill. T

  2. Red blood cell antibodies in pregnancy and their clinical consequences

    DEFF Research Database (Denmark)

    Nordvall, Maria; Dziegiel, Morten Hanefeld; Hegaard, Hanne Kristine;

    2009-01-01

    The objective was to determine clinical consequences of various specificities for the infant/fetus. The population was patients referred between 1998 and 2005 to the tertiary center because of detected red blood cell (RBC) alloimmunization. Altogether 455 infants were delivered by 390 alloimmunized...

  3. Alterations of red blood cell metabolome in overhydrated hereditary stomatocytosis.

    NARCIS (Netherlands)

    Darghouth, D.; Koehl, B.; Heilier, J.F.; Madalinski, G.; Bovee, P.H.; Bosman, G.J.C.G.M.; Delaunay, J.; Junot, C.; Romeo, P.H.

    2011-01-01

    Overhydrated hereditary stomatocytosis, clinically characterized by hemolytic anemia, is a rare disorder of the erythrocyte membrane permeability to monovalent cations, associated with mutations in the Rh-associated glycoprotein gene. We assessed the red blood cell metabolome of 4 patients with this

  4. Challenges for red blood cell biomarker discovery through proteomics

    NARCIS (Netherlands)

    Barasa, B.A.; Slijper, M.

    2014-01-01

    Red blood cells are rather unique body cells, since they have lost all organelles when mature, which results in lack of potential to replace proteins that have lost their function. They maintain only a few pathways for obtaining energy and reducing power for the key functions they need to fulfill. T

  5. Blood volume measurements in gopher snakes, using autologous 51Cr-labeled red blood cells.

    Science.gov (United States)

    Smeller, J M; Bush, M; Seal, U S

    1978-02-01

    Blood volume determinations were performed in 5 anesthetized gopher snakes (Pituophis melanoleucus catenifer) by means of a 51Cr-labeled red blood cell (RBC) method. The mean blood volume was 52.8 ml/kg of body weight (+/- 6.21 SE). Previous blood volume measurements have not been reported for this species. The RBC survival rate was estimated to be greater than 660 days. The RBC survival rate is long, but it cannot be determined accurately by this method.

  6. A novel passive microfluidic device for preprocessing whole blood for point of care diagnostics

    DEFF Research Database (Denmark)

    Shah, Pranjul Jaykumar; Dimaki, Maria; Svendsen, Winnie Edith

    2009-01-01

    A novel strategy to sort the cells of interest (White Blood Cells (leukocytes)) by selectively lysing the Red Blood Cells (erythrocytes) in a miniaturized microfluidic device is presented. Various methods to lyse cells on a chip exist i.e. electrical, mechanical, chemical and thermal but they need...... integration of electrodes, traps, reservoirs, heaters, etc which is often difficult at microscale [1 – 4]. On the other hand, FACSlyse protocol uses only osmotic pressure to lyse erythrocytes allowing further isolation of leukocytes. This motivated us to develop a novel herringbone based lyser which works...

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

    DEFF Research Database (Denmark)

    Liu, Qiyong P; Sulzenbacher, Gerlind; Yuan, Huaiping;

    2007-01-01

    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...... 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....

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

    Science.gov (United States)

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

    2017-03-01

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

  9. Color contrast of red blood cells on solid substrate

    Science.gov (United States)

    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.

  10. Macromolecular Dynamics in Red Blood Cells Investigated Using Neutron Spectroscopy

    CERN Document Server

    Stadler, Andreas Maximilian; Demmel, Franz; Artmann, Gerhard; 10.1098/rsif.2010.0306

    2011-01-01

    We present neutron scattering measurements on the dynamics of hemoglobin (Hb) in human red blood cells in vivo. Global and internal Hb dynamics were measured in the ps to ns time- and {\\AA} length-scale using quasielastic neutron backscattering spectroscopy. We observed the cross-over from global Hb short-time to long-time self-diffusion. Both short- and long-time diffusion coefficients agree quantitatively with predicted values from hydrodynamic theory of non-charged hard-sphere suspensions when a bound water fraction of around 0.23g H2O/ g Hb is taken into account. The higher amount of water in the cells facilitates internal protein fluctuations in the ps time-scale when compared to fully hydrated Hb powder. Slower internal dynamics of Hb in red blood cells in the ns time-range were found to be rather similar to results obtained with fully hydrated protein powders, solutions and E. coli cells.

  11. Aggregation of Red Blood Cells: From Rouleaux to Clot Formation

    CERN Document Server

    Wagner, C; Svetina, S

    2013-01-01

    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 binding 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 binding 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.

  12. Magnetic nanoparticle effects on the red blood cells

    Energy Technology Data Exchange (ETDEWEB)

    Creanga, D E; Nadejde, C; Curecheriu, L [' Al. I. Cuza' University, Faculty of Physics, 11A Blvd. Carol I, Iasi (Romania)], E-mail: dorinacreanga@yahoo.com; Culea, M [' Babes Bolyai' University, Cluj-Napoca (Romania); Oancea, S [University of Veterinary Medicine ' I. Ionescu de la Brad' , Iasi (Romania); Racuciu, M [' Lucian Blaga' University, Sibiu (Romania)

    2009-05-01

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

  13. Magnetic nanoparticle effects on the red blood cells

    Science.gov (United States)

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

    2009-05-01

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

  14. Transfusion of Red Blood Cells to Patients with Sepsis.

    Science.gov (United States)

    Chan, Yi-Ling; Han, Shih-Tsung; Li, Chih-Huang; Wu, Chin-Chieh; Chen, Kuan-Fu

    2017-09-11

    Sepsis is one of the major causes of death worldwide, and is the host response to infection which renders our organs malfunctioning. Insufficient tissue perfusion and oxygen delivery have been implicated in the pathogenesis of sepsis-related organ dysfunction, making transfusion of packed red blood cells (pRBCs) a reasonable treatment modality. However, clinical trials have generated controversial results. Even the notion that transfused pRBCs increase the oxygen-carrying capacity of blood has been challenged. Meanwhile, during sepsis, the ability of our tissues to utilize oxygen may also be reduced, and the increased blood concentrations of lactate may be the results of strong inflammation and excessive catecholamine release, rather than impaired cell respiration. Leukodepleted pRBCs more consistently demonstrated improvement in microcirculation, and the increase in blood viscosity brought about by pRBC transfusion helps maintain functional capillary density. A restrictive strategy of pRBC transfusion is recommended in treating septic patients.

  15. Shear stress-induced improvement of red blood cell deformability

    OpenAIRE

    Meram, Ece; Yılmaz, Bahar D.; Bas, Ceren; Atac, Nazlı; Yalçın, Ö.; Başkurt, Oguz K.; Meiselman, Herbert J.

    2013-01-01

    Classically, it is known that red blood cell (RBC) deformability is determined by the geometric and material properties of these cells. Experimental evidence accumulated during the last decade has introduced the concept of active regulation of RBC deformability. This regulation is mainly related to altered associations between membrane skeletal proteins and integral proteins, with the latter serving to anchor the skeleton to the lipid matrix. It has been hypothesized that shear stress induces...

  16. Acetylsalicylic acid and morphology of red blood cells

    Directory of Open Access Journals (Sweden)

    Jacques Natan Grinapel Frydman

    2010-06-01

    Full Text Available This work evaluated the effect of in vitro and in vivo treatment with ASA on the morphology of the red blood cells. Blood samples or Wistar rats were treated with ASA for one hour. Blood samples or animals treated with saline were used as control group. Blood smears were prepared, fixed, stained and the qualitative and quantitative morphology of red blood cells were evaluated under optical microscopy. Data showed that the in vitro treatment for one hour with ASA at higher dose used significantly (pEste trabalho avaliou o efeito do tratamento in vitro e in vivo com AAS na morfologia dos eritrócitos. Amostras de sangue ou ratos Wistar foram tratadas com AAS por uma hora. Amostras sangüíneas ou animais tratados com salina foram utilizados como grupos controle. Distensões de sangue foram preparadas, fixadas, coradas e a análise morfológica qualitativa e quantitativa dos eritrócitos foi realizada em microscópio óptico. Os dados mostraram que o tratamento in vitro por uma hora com AAS na maior dose utilizada modificou significativamente (p<0.05 a relação perímetro/área dos eritrócitos. Não foram obtidas alterações morfológicas com o tratamento in vivo. O uso do AAS em doses altas poderia interferir na forma dos eritrócitos.

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

    Science.gov (United States)

    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.

  18. RED BLOOD CELL ABNORMALITIES IN DECOMPENSATED CHRONIC LIVER DISEASE (DCLD

    Directory of Open Access Journals (Sweden)

    Anbazhagan

    2015-02-01

    Full Text Available BACKGROUND: Liver plays an important role in normal erythropoiesis, especially in formation and destruction of RBC’s. Chronic liver diseases are frequently associated with hematological abnormalities. Anemia of diverge etiology occurs in about 75% patients with DCLD ( 36. This can ultimately culminate in grave complications. AIM OF THE STUDY: To detect various abnormalities in Red Blood Cells and to assess the type of anemia in DCLD. METHODS: The study was conducted in 50 patients of DCLD, in Meenakshi Medical College. A detailed History, clinical examination and also Ultrasound Abdomen, GI endoscopy to establish DCLD and complete Red Blood Cell assessment was done. RESULTS AND OBSERVATION : Among the 50 patients, 40 patients (80% had anemia and only 10 pts had normal h emoglobin above 13 gms%. About 15 patients (30% had severe Anemia of less than 6 gm%. Among the 40 patients, 25 patients had normocytic normochronic anemia, 10 patients had microcytic anemia, and 4 patients had macrocytosis and only one had dimorphic anem ia. CONCLUSION : Most common Red Blood Cell abnormality in DCLD is anemia (80% and most common anemia is normochronic normocytic anemia (62.5%, while microcytic anemia and macrocytosis were common among females and Alcoholics, respectively

  19. Red-blood-cell alloimmunisation in relation to antigens' exposure and their immunogenicity: a cohort study.

    NARCIS (Netherlands)

    Evers, D.; Middelburg, R.A.; Haas, M. de; Zalpuri, S.; Vooght, K.M. De; Kerkhof, D. van de; Visser, O; Pequeriaux, N.C.V.; Hudig, F.; Schonewille, H.; Zwaginga, J.J.; Bom, J.G. Van Der

    2016-01-01

    BACKGROUND: Matching donor red blood cells based on recipient antigens prevents alloimmunisation. Knowledge about the immunogenicity of red-blood-cell antigens can help optimise risk-adapted matching strategies. We set out to assess the immunogenicity of red-blood-cell antigens. METHODS: In an incid

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

    NARCIS (Netherlands)

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

    2015-01-01

    Cryopreserved (frozen) red blood cells have been used in transfusion medicine since the Vietnam war. The main method to freeze the red blood cells is by usage of glycerol. Although the usage of cryopreserved red blood cells was promising due to the prolonged storage time and the limited cellular det

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

    Science.gov (United States)

    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 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 also be used to better understand the flow

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

    Science.gov (United States)

    Shimizu, Kazuya; Sugiyama, Kazuyasu; Takagi, Shu

    2016-11-01

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

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

    Science.gov (United States)

    Chesnutt, J K W; Marshall, J S

    2010-03-01

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

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

    Science.gov (United States)

    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.

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

    OpenAIRE

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

    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-sus...

  6. A model for red blood cells in simulations of large-scale blood flows

    CERN Document Server

    Melchionna, Simone

    2011-01-01

    Red blood cells (RBCs) are an essential component of blood. A method to include the particulate nature of blood is introduced here with the goal of studying circulation in large-scale realistic vessels. The method uses a combination of the Lattice Boltzmann method (LBM) to account for the plasma motion, and a modified Molecular Dynamics scheme for the cellular motion. Numerical results illustrate the quality of the model in reproducing known rheological properties of blood as much as revealing the effect of RBC structuring on the wall shear stress, with consequences on the development of cardiovascular diseases.

  7. Ex vivo red blood cell hemolysis assay for the evaluation of pH-responsive endosomolytic agents for cytosolic delivery of biomacromolecular drugs.

    Science.gov (United States)

    Evans, Brian C; Nelson, Christopher E; Yu, Shann S; Beavers, Kelsey R; Kim, Arnold J; Li, Hongmei; Nelson, Heather M; Giorgio, Todd D; Duvall, Craig L

    2013-03-09

    Phospholipid bilayers that constitute endo-lysosomal vesicles can pose a barrier to delivery of biologic drugs to intracellular targets. To overcome this barrier, a number of synthetic drug carriers have been engineered to actively disrupt the endosomal membrane and deliver cargo into the cytoplasm. Here, we describe the hemolysis assay, which can be used as rapid, high-throughput screen for the cytocompatibility and endosomolytic activity of intracellular drug delivery systems. In the hemolysis assay, human red blood cells and test materials are co-incubated in buffers at defined pHs that mimic extracellular, early endosomal, and late endo-lysosomal environments. Following a centrifugation step to pellet intact red blood cells, the amount of hemoglobin released into the medium is spectrophotometrically measured (405 nm for best dynamic range). The percent red blood cell disruption is then quantified relative to positive control samples lysed with a detergent. In this model system the erythrocyte membrane serves as a surrogate for the lipid bilayer membrane that enclose endo-lysosomal vesicles. The desired result is negligible hemolysis at physiologic pH (7.4) and robust hemolysis in the endo-lysosomal pH range from approximately pH 5-6.8.

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

    Science.gov (United States)

    Svensson, Annika M; Delaney, Meghan

    2015-01-01

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

  9. Mobility Enhancement of Red Blood Cells with Biopolymers

    Science.gov (United States)

    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.

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

    Science.gov (United States)

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

    2011-10-01

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

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

    DEFF Research Database (Denmark)

    Damgaard, Christian; Magnussen, Karin; Enevold, Christian

    2015-01-01

    ) 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......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...

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

    Directory of Open Access Journals (Sweden)

    Mariia Zhurova

    2012-01-01

    Full Text Available 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.

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

    Science.gov (United States)

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

    2015-02-01

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

  14. Flow of Red Blood Cells in Stenosed Microvessels

    Science.gov (United States)

    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.

  15. Is red blood cell rheology preserved during routine blood bank storage?

    NARCIS (Netherlands)

    Henkelman, Sandra; Dijkstra-Tiekstra, Margriet J.; de Wildt-Eggen, Janny; Graaff, Reindert; Rakhorst, Gerhard; van Oeveren, Willem

    2010-01-01

    BACKGROUND: Red blood cell (RBC) units stored for more than 2 weeks at 4 degrees C are currently considered of impaired quality. This opinion has primarily been based on altered RBC rheologic properties (i.e., enhanced aggregability, reduced deformability, and elevated endothelial cell interaction),

  16. Is red blood cell rheology preserved during routine blood bank storage?

    NARCIS (Netherlands)

    Henkelman, Sandra; Dijkstra-Tiekstra, Margriet J.; de Wildt-Eggen, Janny; Graaff, Reindert; Rakhorst, Gerhard; van Oeveren, Willem

    BACKGROUND: Red blood cell (RBC) units stored for more than 2 weeks at 4 degrees C are currently considered of impaired quality. This opinion has primarily been based on altered RBC rheologic properties (i.e., enhanced aggregability, reduced deformability, and elevated endothelial cell interaction),

  17. The nature of multiphoton fluorescence from red blood cells

    Science.gov (United States)

    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.

  18. General coarse-grained red blood cell models: I. Mechanics

    OpenAIRE

    FEDOSOV, DMITRY A.; Caswell, Bruce; Karniadakis, George E.

    2009-01-01

    We present a rigorous procedure to derive coarse-grained red blood cell (RBC) models, which lead to accurate mechanical properties of realistic RBCs. Based on a semi-analytic theory linear and non-linear elastic properties of the RBC membrane can be matched with those obtained in optical tweezers stretching experiments. In addition, we develop a nearly stress-free model which avoids a number of pitfalls of existing RBC models, such as non-biconcave equilibrium shape and dependence of RBC mech...

  19. Swinging of red blood cells under shear flow

    CERN Document Server

    Abkarian, M; Viallat, A; Abkarian, Manouk; Faivre, Magalie; Viallat, Annie

    2007-01-01

    We reveal that under moderate shear stress (of the order of 0.1 Pa) red blood cells present an oscillation of their inclination (swinging) superimposed to the long-observed steady tanktreading (TT) motion. A model based on a fluid ellipsoid surrounded by a visco-elastic membrane initially unstrained (shape memory) predicts all observed features of the motion: an increase of both swinging amplitude and period (1/2 the TT period) upon decreasing the shear stress, a shear stress-triggered transition towards a narrow shear stress-range intermittent regime of successive swinging and tumbling, and a pure tumbling motion at lower shear stress-values.

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

    Science.gov (United States)

    Peng, Zhangli; Lu, Huijie

    2016-11-01

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

  1. Mechanopathology of red blood cell diseases—Why mechanics matters

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    During the onset of a disease a cell may experience alterations in both the composition and organization of its cellular and molecular structures.These alterations may eventually lead to changes in its geometrical and mechanical properties such as cell size and shape,deformability and adhesion.As such,knowing how diseased cells respond to mechanical forces can reveal ways by which they differ from healthy ones.Here,we will present biomechanistic insights into red blood cell related diseases that manifest...

  2. Manipulation of microparticles and red blood cells using optoelectronic tweezers

    Indian Academy of Sciences (India)

    R S Verma; R Dasgupta; N Kumar; S Ahlawat; A Uppal; P K Gupta

    2014-02-01

    We report the development of an optoelectronic tweezers set-up which works by lightinduced dielectrophoresis mechanism to manipulate microparticles. We used thermal evaporation technique for coating the organic polymer, titanium oxide phthalocyanine (TiOPc), as a photoconductive layer on ITO-coated glass slide. Compare to the conventional optical tweezers, the technique requires optical power in W range and provides a manipulation area of a few mm2. The set-up was used to manipulate the polystyrene microspheres and red blood cells (RBCs). The RBCs could be attracted or repelled by varying the frequency of the applied AC bias.

  3. THE PURE RED BLOOD CELL APLASIA IN RENAL TRANSPLANT RECIPIENT

    Directory of Open Access Journals (Sweden)

    B. T. Dzumabaeva

    2011-01-01

    Full Text Available The pure red blood cell aplasia of renal transplant recipients caused by parvovirus B19 (PB19 is characterized by persistent anemia which resistant to erythropoietin therapy, lack of reticulocytes, bone marrow hypoplasia, and clinically accompanied by severe recurrent bacterial, fungal and viral infection. In case of reactivation PB19 it is necessarv, first of all, eliminate the causes activation of this virus and to cancel or reduce the dose of drugs which depressed the normal hematopoiesis germs, thus to reduce the pancytopenia associating complications in this population. 

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

    Science.gov (United States)

    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 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

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

    Energy Technology Data Exchange (ETDEWEB)

    Nikitin, S Yu; Priezzhev, A V; Lugovtsov, A E [International Laser Center, M. V. Lomonosov Moscow State University, Moscow (Russian Federation); Ustinov, V D [M. V. Lomonosov Moscow State University, Faculty of Computational Mathematics and Cybernetics, Moscow (Russian Federation)

    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)

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

    Science.gov (United States)

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

    1997-10-01

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

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

    Science.gov (United States)

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

    1997-01-01

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

  8. Red cell properties after different modes of blood transportation

    Directory of Open Access Journals (Sweden)

    Asya Makhro

    2016-07-01

    Full Text Available 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 extend 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 hours of simulated shipment conditions. Three different anticoagulants (K3EDTA, Sodium Heparin and citrate-based CPDA for two temperatures (4oC 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 parameter 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 4oC. Whereas plasma and intraerythrocytic Ca2+ cannot be accurately measured in the presence of chelators such as citrate and EDTA, majority of Ca2+-dependent parameters are stabilized in CPDA samples. Even in blood samples from healthy donors transported using optimized shipment protocol the majority of parameters were stable within 24 hours, the condition that may not hold for the samples of patients with rare anemias. This implies for the as short as possible shipping using fast courier services to the closest expert laboratory at reach. Mobile laboratories or the travel of the

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

    Science.gov (United States)

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

    2016-03-07

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

  10. Copper(II) complexes encapsulated in human red blood cells.

    Science.gov (United States)

    Bonomo, R P; De Flora, A; Rizzarelli, E; Santoro, A M; Tabbí, G; Tonetti, M

    1995-09-01

    Copper(II) complexes were encapsulated in human red blood cells in order to test their possible use as antioxidant drugs by virtue of their labile character. ESR spectroscopy was used to verify whether encapsulation in red blood cells leads to the modification of such complexes. With copper(II) complexes bound to dipeptides or tripeptides, an interaction with hemoglobin was found to be present, the hemoglobin having a strong coordinative site formed by four nitrogen donor atoms. Instead, with copper(II) complexes with TAD or PheANN3, which have the greatest stability. ESR spectra always showed the original species. Only the copper(II) complex with GHL gave rise to a complicated behavior, which contained signals from iron(III) species probably coming from oxidative processes. Encapsulation of all copper(II) complexes in erythrocytes caused a slight oxidative stress, compared to the unloaded and to the native cells. However, no significant differences were observed in the major metabolic properties (GSH, glycolytic rate, hexose monophosphate shunt, Ca(2+)-ATPase) of erythrocytes loaded with different copper(II) complexes, with the exception of methemoglobin levels, which were markedly increased in the case of [Cu(GHL)H-1] compared to [Cu(TAD)]. This latter finding suggests that methemoglobin formation can be affected by the type of complex used for encapsulation, depending on the direct interaction of the copper(II) complex with hemoglobin.

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

    Directory of Open Access Journals (Sweden)

    Djuna Zoe de Back

    2014-01-01

    Full Text Available Macrophages tightly control the production and clearance of red blood cells (RBC. During steady state haematopoiesis, approximately 1010 red blood cells 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.

  12. Some technetium complexes for labelling red blood cells

    Energy Technology Data Exchange (ETDEWEB)

    Emery, M.F.

    1988-01-01

    A new approach to produce technetium labelled red blood cells, used routinely in diagnostic nuclear medicine, is reported. The enzyme Carbonic Anhydrase (CA), present in erythrocytes, is strongly inhibited by primary aromatic sulphonamides, which bind at the enzyme active site. Three types of ligand able to coordinate to technetium and suitable for modification to include a primary aromatic sulphonamide group were studied; bis(thiosemicarbazones), Schiff bases and some propylene amine oximes. The experimental conditions needed to label the ligands were determined. Both the thiosemicarbazone and propyleneamine oxime derivatives were labelled, but under no conditions attempted were the Schiff bases complexed by Technetium. The two major isozymes of Human Carbonic Anhydrase, HCA I and HCA II, were isolated from blood. The strength of binding of the free ligands SET, PN130 and PN135 with each of the isozymes was measured and expressed as the Dissociation Constant K{sub d}. The rate of uptake of the technetium complexes into washed RBCs and whole blood was measured and found to be much slower in whole blood. The biodistribution of both TcPN130 and TcPN135 in rats was determined and scintigraphic images for the TcPN130 complex were recorded. Attempts to synthesise the Tc-99 analogues on the milligram scale to allow chemical characterisation of these complexes were unsuccessful. (author).

  13. Zeroing in on red blood cell unit expiry.

    Science.gov (United States)

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

    2017-09-20

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

  14. Calcium-dependent 86 Rb efflux and ethanol intoxication: studies of human red blood cells and rodent brain synaptosomes.

    Science.gov (United States)

    Yamamoto, H A; Harris, R A

    1983-04-08

    Effects of ethanol on calcium-dependent potassium efflux were investigated in red blood cells (RBC) from humans and brain synaptosomes from rats and mice. 86 Rb was used as a tracer for potassium. Synaptosomes and RBC were lysed and resealed with 86 Rb and calcium-EGTA buffers to regulate intracellular levels of ionized calcium. In vitro addition of ethanol (100 mM) stimulated the calcium-dependent 86 Rb efflux of synaptosomes. This stimulation was blocked by apamin, an inhibitor of the calcium-dependent potassium current of nerve cells. In addition, intracerebroventricular injection of apamin inhibited ethanol-induced narcosis in mice, providing behavioral evidence for the importance of calcium-stimulated potassium efflux in alcohol intoxication. In vitro addition of ethanol, propanol or butanol increased calcium-dependent 86 Rb efflux of human RBC at low concentrations of free calcium, but did not change the calcium-independent efflux of 86 Rb. These results suggest that the calcium-dependent 86 Rb efflux of nerve endings may have an important role in the pharmacological and toxicological effects of ethanol.

  15. Leucocyte filtration of salvaged blood during cardiac surgery : effect on red blood cell function in concentrated blood compared with diluted blood

    NARCIS (Netherlands)

    Gu, Y. John; de Vries, Adrianus J.; Hagenaars, J. Ans M.; van Oeveren, Willem

    2009-01-01

    Objective: Leucocyte filtration of salvaged blood has been suggested to prevent patients from receiving activated leucocytes during autotransfusion in cardiac surgery. This study examines whether leucocyte filtration of salvaged blood affects the red blood cell (RBC) function and whether there is a

  16. Profile of Blood Transfusion Requests from Hospitals to Bandung Blood Transfusion Unit, Indonesian Red Cross in 2011

    Directory of Open Access Journals (Sweden)

    Syahla Nisaa Amalia

    2015-09-01

    Full Text Available Background: Blood transfusion as a part health services should be provided under appropriate indications and in a safe manner. In Indonesia, blood collection is run by the Blood Transfusion Unit of Indonesian Red Cross, where the blood is screened, processed into blood components, and finally distributed to hospitals. The purpose of this study was to describe the profile of blood transfusion requests from hospitals that do not have blood bank facility to the Bandung Blood Transfusion Unit, Indonesian Red Cross. Methods: A descriptive study was carried out using secondary data from Bandung Blood Transfusion Unit Indonesian Red Cross (UTD PMI Bandung. All blood request forms from hospitals during 2011 were collected and analyzed. Variables in this study were the amount of blood units, blood components, blood type, and indications of blood transfusion. Results: The number of blood units requested by hospitals were 35,841 units. The most blood units requested was in August 2011. The blood component requested was the packed red cell (61.1%, whole blood (17.4%, thrombocyte concentrate (10.6%, and fresh frozen plasma (7%. The total percentage of O, A, B and AB blood types were 36.1%, 28.6%, 27.5%, and 7.9% respectively. The most frequent indication for transfusion was anemia (61.7%, followed by surgery and other causes of bleeding. Conclusions: The total blood units requested by hospitals vary each month. The most blood component requested is Packed Red Cell and the type of blood is O blood type. The most frequent indication is anemia.

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

    Science.gov (United States)

    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.

  18. Structural Changes in the Surface of Red Blood Cell Membranes during Long-Term Donor Blood Storage

    Directory of Open Access Journals (Sweden)

    V. V. Moroz

    2012-01-01

    Full Text Available Objective: to study changes in the surface of red blood cell membranes of donor blood at the macro- and ultrastructural level during its storage for 30 days and to evaluate the functional state of the red blood cell membrane during the whole storage period. Material and methods. The investigation was conducted on human whole blood and packed red blood cells placed in the specialized packs containing the preservative CPDA-1, by using calibrated electroporation and atomic force microscopy and measuring plasma pH. Conclusion. The long-term, up to 30-day, storage of whole blood and packed red blood cells at 4°C was attended by lower plasma pH and increased hemolysis rate constant during calibrated electroporation and by the development of oxidative processes. The hemolysis rate constant was also higher in the packed red blood cells than that in the whole blood. On days 5—6, the membrane structure showed defects that developed, as the blood was stored, and caused irreversible cell membrane damage by day 30. Key words: donor blood, red blood cell membranes, atomic force microscopy.

  19. Quantification of the fraction poorly deformable red blood cells using ektacytometry

    NARCIS (Netherlands)

    Streekstra, G.J.; Dobbe, J.G.G.; Hoekstra, A.G.

    2010-01-01

    We describe a method to obtain the fraction of poorly deformable red blood cells in a blood sample from the intensity pattern in an ektacytometer. In an ektacytometer red blood cells are transformed into ellipsoids by a shear flow between two transparent cylinders. The intensity pattern, due to a la

  20. Gamma-H2AX biodosimetry for use in large scale radiation incidents: comparison of a rapid ‘96 well lyse/fix’ protocol with a routine method

    Directory of Open Access Journals (Sweden)

    Jayne Moquet

    2014-03-01

    Full Text Available Following a radiation incident, preliminary dose estimates made by γ-H2AX foci analysis can supplement the early triage of casualties based on clinical symptoms. Sample processing time is important when many individuals need to be rapidly assessed. A protocol was therefore developed for high sample throughput that requires less than 0.1 ml blood, thus potentially enabling finger prick sampling. The technique combines red blood cell lysis and leukocyte fixation in one step on a 96 well plate, in contrast to the routine protocol, where lymphocytes in larger blood volumes are typically separated by Ficoll density gradient centrifugation with subsequent washing and fixation steps. The rapid ‘96 well lyse/fix’ method reduced the estimated sample processing time for 96 samples to about 4 h compared to 15 h using the routine protocol. However, scoring 20 cells in 96 samples prepared by the rapid protocol took longer than for the routine method (3.1 versus 1.5 h at zero dose; 7.0 versus 6.1 h for irradiated samples. Similar foci yields were scored for both protocols and consistent dose estimates were obtained for samples exposed to 0, 0.2, 0.6, 1.1, 1.2, 2.1 and 4.3 Gy of 250 kVp X-rays at 0.5 Gy/min and incubated for 2 h. Linear regression coefficients were 0.87 ± 0.06 (R2 = 97.6% and 0.85 ± 0.05 (R2 = 98.3% for estimated versus actual doses for the routine and lyse/fix method, respectively. The lyse/fix protocol can therefore facilitate high throughput processing for γ-H2AX biodosimetry for use in large scale radiation incidents, at the cost of somewhat longer foci scoring times.

  1. International Society of Blood Transfusion Working Party on red cell immunogenetics and blood group terminology: Cancun report (2012).

    Science.gov (United States)

    Storry, J R; Castilho, L; Daniels, G; Flegel, W A; Garratty, G; de Haas, M; Hyland, C; Lomas-Francis, C; Moulds, J M; Nogues, N; Olsson, M L; Poole, J; Reid, M E; Rouger, P; van der Schoot, E; Scott, M; Tani, Y; Yu, L-C; Wendel, S; Westhoff, C; Yahalom, V; Zelinski, T

    2014-07-01

    The International Society of Blood Transfusion Working Party on red cell immunogenetics and blood group terminology convened during the International congress in Cancun, July 2012. This report details the newly identified antigens in existing blood group systems and presents three new blood group systems.

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

    Science.gov (United States)

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

    2017-01-01

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

  3. Axial dispersion in flowing red blood cell suspensions

    Science.gov (United States)

    Podgorski, Thomas; Losserand, Sylvain; Coupier, Gwennou

    2016-11-01

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

  4. Polymer/hemoglobin assemblies: biodegradable oxygen carriers for artificial red blood cells.

    Science.gov (United States)

    Li, Taihang; Jing, Xiabin; Huang, Yubin

    2011-07-07

    In routine clinical procedures, blood transfusion is now suffering from the defects of the blood products, like cross-matching, short storage time and virus infection. Various blood substitutes have been designed by researchers through continual efforts. With recent progress in nanotechnology, new types of artificial red blood cells with cellular structure are available. This article aims to describe some artificial red blood cells which encapsulate or conjugate hemoglobin molecules through various approaches, especially the nanoscale self-assembly technique, to mitigate the adverse effects of free hemoglobin molecules. These types of artificial red blood cell systems, which make use of biodegradable polymers as matrix materials, show advantages over the traditional types.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  6. Length of Storage of Red Blood Cells and Patient Survival After Blood Transfusion

    DEFF Research Database (Denmark)

    Halmin, Märit; Rostgaard, Klaus; Lee, Brian K

    2017-01-01

    Background: Possible negative effects, including increased mortality, among persons who receive stored red blood cells (RBCs) have recently garnered considerable attention. Despite many studies, including 4 randomized trials, no consensus exists. Objective: To study the association between...... received transfusions from 2003 to 2012. Measurements: Patients were followed from first blood transfusion. Relative and absolute risks for death in 30 days or 1 year in relation to length of RBC storage were assessed by using 3 independent analytic approaches. All analyses were conducted by using Cox...... proportional hazards regression. Results: Regardless of the analytic approach, no association was found between the length of RBC storage and mortality. The difference in 30-day cumulative mortality between patients receiving blood stored for 30 to 42 days and those receiving blood stored for 10 to 19 days...

  7. Restrictive versus liberal transfusion strategy for red blood cell transfusion

    DEFF Research Database (Denmark)

    Holst, Lars B; Petersen, Marie W; Haase, Nicolai;

    2015-01-01

    OBJECTIVE: To compare the benefit and harm of restrictive versus liberal transfusion strategies to guide red blood cell transfusions. DESIGN: Systematic review with meta-analyses and trial sequential analyses of randomised clinical trials. DATA SOURCES: Cochrane central register of controlled...... trials, SilverPlatter Medline (1950 to date), SilverPlatter Embase (1980 to date), and Science Citation Index Expanded (1900 to present). Reference lists of identified trials and other systematic reviews were assessed, and authors and experts in transfusion were contacted to identify additional trials....... TRIAL SELECTION: Published and unpublished randomised clinical trials that evaluated a restrictive compared with a liberal transfusion strategy in adults or children, irrespective of language, blinding procedure, publication status, or sample size. DATA EXTRACTION: Two authors independently screened...

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

    Science.gov (United States)

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

    2017-02-27

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

  9. Geometric localization of thermal fluctuations in red blood cells

    Science.gov (United States)

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

    2017-01-01

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

  10. Red blood cell sodium transport in patients with cirrhosis

    DEFF Research Database (Denmark)

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

    2016-01-01

    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) , Psodium (r = 0·57, P......sodium efflux was higher in patients with cirrhosis (+46%, Psodium buffers showed that the F-insensitive sodium efflux was twice as high in cirrhosis as in controls (P = 0...

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

    Science.gov (United States)

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

    2017-01-01

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

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

    Science.gov (United States)

    Mancuso, Jordan; Ristenpart, William

    2016-11-01

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

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

    Science.gov (United States)

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

    2013-01-01

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

  14. Manipulation on human red blood cells with femtosecond optical tweezers

    Institute of Scientific and Technical Information of China (English)

    Ming Zhou; Haifeng Yang; Jianke Di; Enlan Zhao

    2008-01-01

    Different types of femtosecond optical tweezers have become a powerful tool in the modern biological field. However, how to control the irregular targets, including biological cells, using femtosecond optical tweezers remains to be explored. In this study, human red blood cells (hRBCs) are manipulated with femtosecond optical tweezers, and their states under different laser powers are investigated. The results indicate that optical potential traps only can capture the edge of hRBCs under the laser power from 1.4 to 2.8 mW, while it can make hRBCs turn over with the laser power more than 2.8 roW. It is suggested that femtosecond optical tweezers could not only manipulate biological cells, but also subtly control its states by adjusting the laser power.

  15. Autoimmune Hemolytic Anemia and Red Blood Cell Autoantibodies.

    Science.gov (United States)

    Quist, Erin; Koepsell, Scott

    2015-11-01

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

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

    Science.gov (United States)

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

    2009-03-01

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

  17. Diagnosis and epidemiology of red blood cell enzyme disorders

    Directory of Open Access Journals (Sweden)

    Richard Van Wijk

    2013-03-01

    Full Text Available The red blood cell possess an active metabolic machinery that provides the cell with energy to pump ions against electrochemical gradients, to maintain its shape, to keep hemoglobin iron in the reduced (ferrous form, and to maintain enzyme and hemoglobin sulfhydryl groups. The main source of metabolic energy comes from glucose. Glucose is metabolized through the glycolytic pathway and through the hexose monophosphate shunt. Glycolysis catabolizes glucose to pyruvate and lactate, which represent the end products of glucose metabolism in the erythrocyte. Adenosine diphosphate (ADP is phosphorylated to adenosine triphosphate (ATP, and nicotinamide adenine dinucleotide (NAD+ is reduced to NADH in glycolysis. 2,3- Bisphosphoglycerate, an important regulator of the oxygen affinity of hemoglobin, is generated during glycolysis by the Rapoport-Luebering shunt. The hexose monophosphate shunt oxidizes glucose-6-phosphate, reducing NADP+ to reduced nicotinamide adenine dinucleotide phosphate (NADPH. The red cell lacks the capacity for de novo purine synthesis but has a salvage pathway that permits synthesis of purine nucleotides from purine bases...

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

    Science.gov (United States)

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

    2014-09-01

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

  19. Red Blood Cell Transfusions in Greece: Results of a Survey of Red Blood Cell Use in 2013

    Directory of Open Access Journals (Sweden)

    Serena Valsami

    2017-03-01

    Full Text Available Objective: Greece is ranked as the second highest consumer of blood components in Europe. For an effective transfusion system and in order to reduce variability of transfusion practice by implementing evidence-based transfusion guidelines it is necessary to study and monitor blood management strategies. Our study was conducted in order to evaluate the use of red blood cell units (RBC-U in nationwide scale mapping parameters that contribute to their proper management in Greece. Materials and Methods: The survey was conducted by the Working Committee of Transfusion Medicine&Apheresis of the Hellenic Society of Hematology from January to December 2013. The collected data included the number, ABO/D blood group, patients’ department, and storage age of RBC-U transfused. Results: The number of RBC-U evaluated was 103,702 (17.77% out of 583,457 RBC-U transfused in Greece in 2013. RBC-U transfused by hospital department (mean percentage was as follows: Surgery 29.34%, Internal Medicine 29.48%, Oncology/Hematology 14.65%, Thalassemia 8.87%, Intensive Care Unit 6.55%, Nephrology 1.78%, Obstetrics/Gynecology 1.46%, Neonatal&Pediatric 0.31%, Private Hospitals 8.57%. RBC-U distribution according to ABO/D blood group was: A: 39.02%, B: 12.41%, AB: 5.16%, O: 43.41%, D+: 87.99%, D-: 12.01%. The majority of RBC-U (62.46% was transfused in the first 15 days of storage, 25.24% at 16 to 28 days, and 12.28% at 29-42 days. Conclusion: Despite a high intercenter variability in RBC transfusions, surgical and internal medicine patients were the most common groups of patients transfused with an increasing rate for internal medicine patients. The majority of RBC-U were transfused within the first 15 days of storage, which is possibly the consequence of blood supply insufficiency leading to the direct use of fresh blood. Benchmarking transfusion activity may help to decrease the inappropriate use of blood products, reduce the cost of care, and optimize the use of the

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

    Science.gov (United States)

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

    2016-09-12

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

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

    Science.gov (United States)

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

    2014-10-01

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

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

    Institute of Scientific and Technical Information of China (English)

    Chong Lei; Li-Ze Xiong

    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.

  3. Manipulation of red blood cells with electric field

    Science.gov (United States)

    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.

  4. Calcium in Red Blood Cells—A Perilous Balance

    Directory of Open Access Journals (Sweden)

    Lars Kaestner

    2013-05-01

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

  5. Mechanical damage of red blood cells by rotary blood pumps: selective destruction of aged red blood cells and subhemolytic trauma.

    Science.gov (United States)

    Sakota, Daisuke; Sakamoto, Ryuki; Sobajima, Hideo; Yokoyama, Naoyuki; Waguri, Satoshi; Ohuchi, Katsuhiro; Takatani, Setsuo

    2008-10-01

    In this study, mean cell volume (MCV), mean cell hemoglobin concentration (MCHC), and mean cell hemoglobin (MCH) were measured to quantify RBC damage by rotary blood pumps. Six-hour hemolysis tests were conducted with a Bio-pump BPX-80, a Sarns 15200 roller pump, and a prototype mag-lev centrifugal pump (MedTech Heart) using fresh porcine blood circulated at 5 L/min against a 100 mm Hg head pressure. The temperature of the test and noncirculated control blood was maintained at 37 degrees C. The normalized index of hemolysis (NIH) of each pump was determined by measuring the plasma-free hemoglobin level. The MCV was measured with a Coulter counter, and MCHC was derived from total hemoglobin and hematocrit. MCH was derived from MCV and MCHC. A multivariance statistical analysis (ANOVA) revealed statistically significant differences (n = 15, P < 0.05) in MCV, MCHC, and MCH between the blood sheared by the rotary blood pumps and the nonsheared control blood. Normalized to the control blood, the Bio-pump BPX-80 showed an MCV of 1.04 +/- 0.03, an MCHC of 0.95 +/- 0.04, and an MCH of 0.98 +/- 0.02; the mag-lev MedTech Heart had an MCV of 1.02 +/- 0.02, an MCHC of 0.97 +/- 0.02, and an MCH of 0.99 +/- 0.01; and the roller pump exhibited an MCV of 1.03 +/- 0.03, an MCHC of 0.96 +/- 0.03, and an MCH of 0.99 +/- 0.01. Per 0.01 increase in NIH, the BPX-80 showed a normalized MCV change of +10.1% and a normalized MCHC change of -14.0%; the MedTech Heart demonstrated a +6.9% MCV and -9.5% MCHC change; and the roller pump had a +0.5% MCV and -0.6% MCHC change. Due to shear in the pump circuits, the RBC increased while the MCHC decreased. The likely mechanism is that older RBCs with smaller size and higher hemoglobin concentration were destroyed fast by the shear, leaving younger RBCs with larger size and lower hemoglobin concentration. Subhemolytic trauma caused the intracellular hemoglobin to decrease due to gradual hemoglobin leakage through the micropores formed in the thinned

  6. The relationship between stroke mortality and red blood cell parameters.

    Directory of Open Access Journals (Sweden)

    Hamidreza Hatamian

    2014-12-01

    Full Text Available Several factors influence on the outcome of ischemic stroke. The aim of this study was determination the relationship between stroke mortality and red blood cell parameters.This cross-sectional study was conducted from 2011 July to June 2012. For all patients with ischemic stroke in middle cerebral artery (MCA territory, the cell blood count test was performed. We recorded their mortality on the 1(st week and the 1(st month after ischemic stroke. Data analysis was performed using t-test, χ(2, Mann-Whitney U-test, logistic regression and receiver operating characteristic curve in SPSS for Windows 19.0.A total of 98 subjects (45.9% men and 54.1% women with the mean age of 71.0 ± 13.9 years were assessed, while 67.3% of them were anemic. The prevalence of 1(st week mortality among anemic and non-anemic patients was 40.9% and 34.4% (P = 0.534. The prevalence of mortality after 1(st week till 1(st month was 19.6% and 21.0% respectively (P = 0.636. In univariant analysis, only 1(st month mortality had a significant relationship with red blood cell (RBC count (P = 0.022. However, the result of logistic regression model showed that RBC (P = 0.012 and mean corpuscular volume (MCV (P = 0.021 remained as predictors of the 1(st week and the 1(st month mortality (P = 0.011 and P = 0.090 respectively. The best cutoff point of RBC for the prediction of the 1(st week mortality with 44.7% specificity and 69.5% sensitivity was estimated 4.07 million/μl and for the 1(st month mortality with 46.6% specificity and 72.2% sensitivity was estimated 4.16 million/μl.The RBC count and MCV are independent predictors of ischemic stroke short-term mortality.

  7. Red blood cell transfusion in preterm neonates: current perspectives

    Directory of Open Access Journals (Sweden)

    Chirico G

    2014-06-01

    Full Text Available Gaetano ChiricoNeonatology and Neonatal Intensive Care Unit, Children Hospital, Spedali Civili, Brescia, ItalyAbstract: Preterm neonates, especially very low birth weight infants, remain a category of patients with high transfusion needs; about 90% of those with <1,000 g birth weight may be transfused several times during their hospital stay. However, neonatal red blood cells (RBC transfusion is not without risks. In addition to well-known adverse events, several severe side effects have been observed unique to preterm infants, such as transfusion-related acute gut injury, intraventricular hemorrhage, and increased mortality risk. It is therefore important to reduce the frequency of RBC transfusion in critically ill neonates, by delayed clamping or milking the umbilical cord, using residual cord blood for initial laboratory investigations, reducing phlebotomy losses, determining transfusion guidelines, and ensuring the most appropriate nutrition, with the optimal supplementation of iron, folic acid, and vitamins. Ideally, RBC transfusion should be tailored to the individual requirements of the single infant. However, many controversies still remain, and the decision on whether to transfuse or not is often made on an empirical basis. Recently, a few clinical trials have been performed with the aim to compare the risk/benefit ratio of restrictive versus liberal transfusion criteria. No significant differences in short-term outcomes were observed, suggesting that the restrictive criteria may reduce the need for transfusion and the related side effects. Neurodevelopmental long-term outcome seemed more favorable in the liberal group at first evaluation, especially for boys, and significantly better in the restrictive group at a later clinical investigation. Magnetic resonance imaging scans, performed at an average age of 12 years, showed that intracranial volume was substantially smaller in the liberal group compared with controls. When sex effects

  8. Intracellular trehalose improves the survival of human red blood cells by freeze-drying

    Institute of Scientific and Technical Information of China (English)

    HE Hui; LIU Baolin; HUA Zezhao; LI Chuan; WU Zhengzheng

    2007-01-01

    Freeze-drying of human red blood cells has a potential important application for blood transfusion.The aim of this study was to investigate the effects ofintracellular trehalose on the survival of red blood cells after freeze-drying and rehydration.Fresh red blood cells were incubated in trehalose solutions of various concentrations at 37℃ for 7 h following freeze-drying.Polyvinylpyrrolidone,Trehalose,sodium citrate,and human serum albumin were used as extracellular protective agents for the freeze-drying of red blood cells.The results indicated that the intracellular trehalose concentration was increased with increasing concentration of extracellular trehalose solution,and the maximum concen tration of intracellular trehalose reached 35 mmol/L.The viability of freeze-dried red blood cells increased with the increment of intracellular trehalose concentration.

  9. Evaluation of an additive solution for preservation of canine red blood cells.

    Science.gov (United States)

    Wardrop, K J; Owen, T J; Meyers, K M

    1994-01-01

    The effect of an additive preservative solution on canine red blood cell posttransfusion viability (PTV) and on selected canine red blood cell biochemical parameters was studied. One unit (450 mL) of blood was collected from 6 clinically normal dogs into the anticoagulant citrate phosphate dextrose, centrifuged, and the plasma removed. The red blood cells were then suspended in 100 mL of a saline, adenine, dextrose, and mannitol solution and stored at 4 degrees C. Aliquots were removed for study at 1, 10, 20, 30, 37, and 44 days. The 24-hour PTV of autologous red blood cells was determined using a sodium chromate (51Cr) label. Red blood cell concentrations of 2,3-diphosphoglycerate (2,3-DPG), adenosine-5'-triphosphate (ATP), and pH were also determined. Canine red blood cell PTV, pH, ATP, and 2,3-DPG concentrations decreased during storage (P Food and Drug Administration (FDA) minimum standard for human red blood cells, the PTV was substandard in 75% of the day 44 units. The FDA standard was exceeded in 83% of the day 37 units. It was concluded that 37-day-old canine red blood cells preserved with a saline, adenine, dextrose, and mannitol solution are of acceptable quality for transfusion.

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

    Science.gov (United States)

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

    2016-09-08

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

  11. Alterations in cell surface area and deformability of individual human red blood cells in stored blood

    CERN Document Server

    Park, HyunJoo; Lee, SangYun; Kim, Kyoohyun; Sohn, Yong-Hak; Jang, Seongsoo; Park, YongKeun

    2015-01-01

    The functionality and viability of stored human red blood cells (RBCs) is an important clinical issue in transfusion. To systematically investigate changes in stored whole blood, the hematological properties of individual RBCs were quantified in blood samples stored for various periods with and without a preservation solution called CPDA-1. With 3-D quantitative phase imaging techniques, the optical measurements of the 3-D refractive index (RI) distributions and membrane fluctuations were done at the individual cell level. From the optical measurements, the morphological (volume, surface area and sphericity), biochemical (hemoglobin content and concentration), and mechanical parameters (dynamic membrane fluctuation) were simultaneously quantified to investigate the functionalities and their progressive alterations in stored RBCs. Our results show that the stored RBCs without CPDA-1 had a dramatic morphological transformation from discocytes to spherocytes within 2 weeks which was accompanied with significant ...

  12. Net haemoglobin increase from reinfusion of refrigerated vs. frozen red blood cells after autologous blood transfusions

    DEFF Research Database (Denmark)

    Ashenden, M; Mørkeberg, Jakob Sehested

    2011-01-01

    objective was to examine which storage procedure yielded the largest increase in circulating haemoglobin after reinfusion compared to baseline. MATERIALS AND METHODS  Equal volumes of blood from 15 men were withdrawn and stored either frozen or refrigerated as packed red blood cells. Serial measures...... freezing. Nevertheless, frozen storage allowed haemoglobin to fully recover before reinfusion, while the haemoglobin was 10% lower in the refrigerated group compared with baseline. After reinfusion, the haemoglobin levels were 11·5% higher than the baseline values in the group reinfused with frozen blood......, while for the refrigerated group, haemoglobin levels were only 5·2% higher than baseline. CONCLUSION  The relatively larger recovery from anaemia in the frozen group during storage more than compensated for the larger loss of haemoglobin during freezing and resulted in a larger net gain in haemoglobin...

  13. Generation of red blood cells from human embryonic/induced pluripotent stem cells for blood transfusion.

    Science.gov (United States)

    Ebihara, Yasuhiro; Ma, Feng; Tsuji, Kohichiro

    2012-06-01

    Red blood cell (RBC) transfusion is necessary for many patients with emergency or hematological disorders. However, to date the supply of RBCs remains labile and dependent on voluntary donations. In addition, the transmission of infectious disease via blood transfusion from unspecified donors remains a risk. Establishing a large quantity of safe RBCs would help to address this issue. Human embryonic stem (hES) cells and the recently established human induced pluripotent stem (hiPS) cells represent potentially unlimited sources of donor-free RBCs for blood transfusion, as they can proliferate indefinitely in vitro. Extensive research has been done to efficiently generate transfusable RBCs from hES/iPS cells. Nevertheless, a number of challenges must be overcome before the clinical usage of hES/iPS cell-derived RBCs can become a reality.

  14. Sodium renders endothelial cells sticky for red blood cells

    Directory of Open Access Journals (Sweden)

    Hans eOberleithner

    2015-06-01

    Full Text Available Negative charges in the glycocalyx of red blood cells (RBC and vascular endothelial cells (EC facilitate frictionless blood flow through blood vessels. Na+ selectively shields these charges controlling surface electronegativity. The question was addressed whether the ambient Na+ concentration controls RBC-EC interaction. Using atomic force microscopy (AFM adhesion forces between RBC and endothelial glycocalyx were quantified. A single RBC, mounted on an AFM cantilever, was brought in physical contact with the endothelial surface and then pulled off. Adhesion forces were quantified (i after enzymatic removal of negative charges in the glycocalyx, (ii under different ambient Na+ and (iii after applying the intracellular aldosterone receptor antagonist spironolactone. Removal of negative surface charges increases RBC-EC interaction forces. A stepwise increase of ambient Na+ from 133 to 140 mM does not affect them. However, beyond 140 mM Na+ adhesion forces increase sharply (10% increase of adhesion force per 1 mM increase of Na+. Spironolactone prevents this response. It is concluded that negative charges reduce adhesion between RBC and EC. Ambient Na+ concentration determines the availability of free negative charges. Na+ concentrations in the low physiological range (below 140 mM allow sufficient amounts of vacant negative charges so that adhesion of RBC to the endothelial surface is small. In contrast, Na+ in the high physiological range (beyond 140 mM saturates the remaining negative surface charges thus increasing adhesion. Aldosterone receptor blockade by spironolactone prevents Na+ induced RBC adhesion to the endothelial glycocalyx. Extrapolation of in vitro experiments to in vivo conditions leads to the hypothesis that high sodium intake is likely to increase the incidence of thrombotic events.

  15. Sodium renders endothelial cells sticky for red blood cells.

    Science.gov (United States)

    Oberleithner, Hans; Wälte, Mike; Kusche-Vihrog, Kristina

    2015-01-01

    Negative charges in the glycocalyx of red blood cells (RBC) and vascular endothelial cells (EC) facilitate frictionless blood flow through blood vessels. Na(+) selectively shields these charges controlling surface electronegativity. The question was addressed whether the ambient Na(+) concentration controls RBC-EC interaction. Using atomic force microscopy (AFM) adhesion forces between RBC and endothelial glycocalyx were quantified. A single RBC, mounted on an AFM cantilever, was brought in physical contact with the endothelial surface and then pulled off. Adhesion forces were quantified (i) after enzymatic removal of negative charges in the glycocalyx, (ii) under different ambient Na(+) and (iii) after applying the intracellular aldosterone receptor antagonist spironolactone. Removal of negative surface charges increases RBC-EC interaction forces. A stepwise increase of ambient Na(+) from 133 to 140 mM does not affect them. However, beyond 140 mM Na(+) adhesion forces increase sharply (10% increase of adhesion force per 1 mM increase of Na(+)). Spironolactone prevents this response. It is concluded that negative charges reduce adhesion between RBC and EC. Ambient Na(+) concentration determines the availability of free negative charges. Na(+) concentrations in the low physiological range (below 140 mM) allow sufficient amounts of vacant negative charges so that adhesion of RBC to the endothelial surface is small. In contrast, Na(+) in the high physiological range (beyond 140 mM) saturates the remaining negative surface charges thus increasing adhesion. Aldosterone receptor blockade by spironolactone prevents Na(+) induced RBC adhesion to the endothelial glycocalyx. Extrapolation of in vitro experiments to in vivo conditions leads to the hypothesis that high sodium intake is likely to increase the incidence of thrombotic events.

  16. The effects of non-leukoreduced red blood cell transfusions on microcirculation in mixed surgical patients.

    NARCIS (Netherlands)

    Ayhan, B.; Yuruk, K.; Koene, S.; Sahin, A.; Ince, C.; Aypar, U.

    2013-01-01

    BACKGROUND: The impact of the storage process on oxygen-carrying properties of red blood cells and the efficacy of red blood cell (RBC) transfusions concerning tissue oxygenation remain an issue of debate in transfusion medicine. Storage time and leukocyte content probably interact since longer stor

  17. Preoperative factors associated with red blood cell transfusion in hip fracture patients

    DEFF Research Database (Denmark)

    Madsen, Christian Medom; Jørgensen, Henrik Løvendahl; Norgaard, Astrid

    2014-01-01

    Red blood cell (RBC) transfusion is a frequently used treatment in patients admitted with a fractured hip, but the use remains an area of much debate. The aim of this study was to determine preoperative factors associated with the risk of receiving a red blood cell transfusion in hip fracture...

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  20. P2X and P2Y receptor signaling in red blood cells

    Directory of Open Access Journals (Sweden)

    Ronald eSluyter

    2015-10-01

    Full Text Available 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.

  1. A role for activated endothelial cells in red blood cell clearance: implications for vasopathology

    DEFF Research Database (Denmark)

    Fens, Marcel H A M; van Wijk, Richard; Andringa, Grietje

    2012-01-01

    Background Phosphatidylserine exposure by red blood cells is acknowledged as a signal that initiates phagocytic removal of the cells from the circulation. Several disorders and conditions are known to induce phosphatidylserine exposure. Removal of phosphatidylserine-exposing red blood cells gener...... cells play a role in red blood cell clearance in vivo. Significant erythrophagocytosis can induce endothelial cell loss, which may contribute to vasopathological effects as seen, for instance, in sickle cell disease.......Background Phosphatidylserine exposure by red blood cells is acknowledged as a signal that initiates phagocytic removal of the cells from the circulation. Several disorders and conditions are known to induce phosphatidylserine exposure. Removal of phosphatidylserine-exposing red blood cells...... generally occurs by macrophages in the spleen and liver. Previously, however, we have shown that endothelial cells are also capable of erythrophagocytosis. Key players in the erythrophagocytosis by endothelial cells appeared to be lactadherin and αv-integrin. Phagocytosis via the phosphatidylserine...

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

    Science.gov (United States)

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

    2016-11-01

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

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

    Science.gov (United States)

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

    2012-08-01

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

  4. Vesiculation of healthy and defective red blood cells

    Science.gov (United States)

    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.

  5. Measurement of limb blood flow using technetium-labelled red blood cells

    Energy Technology Data Exchange (ETDEWEB)

    Parkin, A; Robinson, P.J.; Wiggins, P.A.; Leveson, S.H.; Salter, M.C.P.; Matthews, I.F.; Ware, F.M.

    1986-05-01

    A method for measuring blood flow below the knee during reactive hyperaemia induced by 3 min of arterial occlusion has been developed. Subjects are positioned with lower limbs within the field of view of a gamma camera and pneumatic cuffs are placed below the knees to isolate the blood and induce a hyperaemic response. The remaining blood pool is labelled with /sup 99/Tcsup(m)-labelled red cells. Blood flows have been derived from the initial gradients of time-activity curves and from equilibrium blood sampling. The technique has been validated using a tissue-equivalent leg phantom and peristaltic pump. The method has been applied to a small group of patients with peripheral vascular disease and to normal controls. The mean value (+-SD) of limb perfusion for normal controls was found to be 16.4 +- 3.0 ml/100 ml/min and for patients with intermittent claudication was 5.1 +- 2.6 ml/100 ml/min. Flow measurements are found to correlate with clinical findings and with symptoms. Reproducibility (established by repeated measurements) is high. The method is well tolerated even by patients suffering from rest pain.

  6. Ultrasensitive detection of cell lysing in an microfabricated semiconductor laser cavity

    Energy Technology Data Exchange (ETDEWEB)

    Gourley, P.L.; French, T.; McDonald, A.E.; Shields, E.A. [Sandia National Labs., Albuquerque, NM (United States); Gourley, M.F. [Washington Hospital Center, Washington, DC (United States)

    1998-01-01

    In this paper the authors report investigations of semiconductor laser microcavities for use in detecting changes of human blood cells during lysing. By studying the spectra before and during mixing of blood fluids with de-ionized water, they are able to quantify the cell shape and concentration of hemoglobin in real time during the dynamical process of lysing. The authors find that the spectra can detect subtle changes that are orders of magnitude smaller than can be observed by standard optical microscopy. Such sensitivity in observing cell structural changes has implications for measuring cell fragility, monitoring apoptotic events in real time, development of photosensitizers for photodynamic therapy, and in-vitro cell micromanipulation techniques.

  7. [Molecular basis of red blood cell adhesion to endothelium].

    Science.gov (United States)

    Wautier, J-L; Wautier, M-P

    2011-01-01

    The extent of red blood cell adhesion is correlated with the incidence of vascular complications and the severity of the disease. Patients with sickle cell anemia (HbSS) experience vasoocclusive episodes. The adhesion of RBCs from HbSS patients is increased and related to VLA-4 exposure, which binds to vascular cell adhesion molecule (VCAM-1). Inter Cellular Adhesion Molecule (ICAM-1), CD31, CD36 and glycans are potential receptors for PfEMP1 of RBCs parasited by plasmodium falciparum. The incidence of vascular complications is very high in patients with diabetes mellitus. RBC adhesion is increased and statistically correlated with the severity of the angiopathy. Glycation of RBC membrane proteins is responsible for binding to the receptor for advanced glycation end products (RAGE). Polycythemia Vera (PV) is the most frequent myeloproliferative disorder and characterized by a high occurrence of thrombosis of mesenteric and cerebral vessels. PV is due to a mutation of the Janus kinase 2 (JAK2 V617F). This mutation stimulates erythropoiesis and is the cause of Lu/BCAM (CD239) phosphorylation, which potentiated the interaction with laminin alpha 5. The couple laminin alpha 5 endothelial and phosphorylated Lu/BCAM explained the increased adhesion of RBCs from patients PV to endothelium.

  8. Amyloid β levels in human red blood cells.

    Directory of Open Access Journals (Sweden)

    Takehiro Kiko

    Full Text Available UNLABELLED: Amyloid β-peptide (Aβ is hypothesized to play a key role by oxidatively impairing the capacity of red blood cells (RBCs to deliver oxygen to the brain. These processes are implicated in the pathogenesis of Alzheimer's disease (AD. Although plasma Aβ has been investigated thoroughly, the presence and distribution of Aβ in human RBCs are still unclear. In this study, we quantitated Aβ40 and Aβ42 in human RBCs with ELISA assays, and provided evidence that significant amounts of Aβ could be detected in RBCs and that the RBC Aβ levels increased with aging. The RBC Aβ levels increased with aging. On the other hand, providing an antioxidant supplement (astaxanthin, a polar carotenoid to humans was found to decrease RBC Aβ as well as oxidative stress marker levels. These results suggest that plasma Aβ40 and Aβ42 bind to RBCs (possibly with aging, implying a pathogenic role of RBC Aβ. Moreover, the data indicate that RBC Aβ40 and Aβ42 may constitute biomarkers of AD. As a preventive strategy, therapeutic application of astaxanthin as an Aβ-lowering agent in RBCs could be considered as a possible anti-dementia agent. TRIAL REGISTRATION: Controlled-Trials.com ISRCTN42483402.

  9. A multiscale model for red blood cell mechanics.

    Science.gov (United States)

    Hartmann, Dirk

    2010-02-01

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

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

    Science.gov (United States)

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

    2008-01-01

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

  11. Human red blood cells deformed under thermal fluid flow.

    Science.gov (United States)

    Foo, Ji-Jinn; Chan, Vincent; Feng, Zhi-Qin; Liu, Kuo-Kang

    2006-03-01

    The flow-induced mechanical deformation of a human red blood cell (RBC) during thermal transition between room temperature and 42.0 degrees C is interrogated by laser tweezer experiments. Based on the experimental geometry of the deformed RBC, the surface stresses are determined with the aid of computational fluid dynamics simulation. It is found that the RBC is more deformable while heating through 37.0 degrees C to 42.0 degrees C, especially at a higher flow velocity due to a thermal-fluid effect. More importantly, the degree of RBC deformation is irreversible and becomes softer, and finally reaches a plateau (at a uniform flow velocity U > 60 microm s(-1)) after the heat treatment, which is similar to a strain-hardening dominated process. In addition, computational simulated stress is found to be dependent on the progression of thermotropic phase transition. Overall, the current study provides new insights into the highly coupled temperature and hydrodynamic effects on the biomechanical properties of human erythrocyte in a model hydrodynamic flow system.

  12. Why does the mammalian red blood cell have aquaporins?

    Science.gov (United States)

    Kuchel, Philip W; Benga, Gheorghe

    2005-11-01

    Aquaporins are now known to mediate the rapid exchange of water across the plasma membranes of diverse cell types. This exchange has been studied and kinetically characterized in red blood cells (erythrocytes; RBC) from many animal species. In recent years, a favoured method has been one based on NMR spectroscopy. Despite knowledge of their molecular structure the physiological raison d' etre of aquaporins in RBCs is still only speculated upon. Here, we present two hypotheses that account for the fact that the exchange of water is so fast in RBCs. The first is denoted the "oscillating sieve" hypothesis and it posits that known membrane undulations at frequencies up to 30 Hz with displacements up to 0.3 microm are energetically favoured by the high water permeability of the membrane. The second denoted the "water displacement" hypothesis is based on the known rapid exchange across the RBC membrane of ions such as Cl- and HCO3- and solutes such as glucose, all of whose molecular volumes are significantly greater than that of water. The ideas are generalizable to other cell types and organelles.

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

    Science.gov (United States)

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

    2013-09-03

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

  14. Dynamics of Red Blood Cells through submicronic splenic slits

    Science.gov (United States)

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

    2016-11-01

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

  15. Characterization of Red Blood Cells with Multiwavelength Transmission Spectroscopy

    Directory of Open Access Journals (Sweden)

    Yulia M. Serebrennikova

    2015-01-01

    Full Text Available 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.

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

    Science.gov (United States)

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

    2006-08-01

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

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

    Science.gov (United States)

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

    2017-01-01

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

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

    Science.gov (United States)

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

    2013-04-01

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

  19. Effect of Packed Red Blood Cell Cryopreservation on Development of the Storage Lesion and Inflammation

    Science.gov (United States)

    2015-09-01

    liquid storage on development of the biochemical, metabolic, and morphologic changes collectively known as the red blood cell storage lesion is unknown...adjunct to standard blood banking techniques. The post-thaw characteristics are markedly different than fresh packed red blood cells, and the...Drug Administration currently restricts their use to 14 days after thawing. The effect of longer term liquid storage on development of the

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

    Science.gov (United States)

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

    2016-01-01

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

  1. Pyruvate effects on red blood cells during in vitro cardiopulmonary bypass with dogs' blood.

    Science.gov (United States)

    Gou, DaMing; Tan, HongJing; Cai, HuiJun; Zhou, FangQiang

    2012-11-01

    To investigate the effects of pyruvate (Pyr) on adenosine triphosphate (ATP), endothelial nitric oxide synthase (eNOS), and nitric oxide (NO) in red blood cells (RBCs) during the cardiopulmonary bypass procedure (CPB), blood, 500 mL, was collected from each of 10 healthy dogs (weight 12-18 kg). The blood was divided into two parts (250 mL each) and randomly assigned into the control group (Group C, n = 10) or the Pyr group (Group P, n = 10). The blood was commingled with an equal volume of 0.9% NaCl and pyruvated isotonic solution (Pyr 50 mM) in the extracorporeal circuit in the two groups, respectively. The CPB procedure was fixed at 120 min, and the transferring flow was 4 L/min. Contents of ATP in RBCs, eNOS activities, and NO productions in plasma were measured before CPB and during CPB at 30, 60, 90, and 120 min in both groups. The ATP level, eNOS activity, and NO production were not different prior to CPB between the two groups. A decline of ATP levels was shown in both groups but remained significantly higher in Group P than in Group C at the same time points during in vitro CPB (P dogs' RBCs in the ATP level, eNOS activity, and NO production, in vitro, but Pyr effectively protected RBCs in these functions during CPB. Pyr would be clinically protective for RBCs during CPB.

  2. Transfusion of leukocyte-depleted red blood cells is not a risk factor for nosocomial infections in critically ill children

    NARCIS (Netherlands)

    van der Wal, Judith; van Heerde, Marc; Markhorst, Dick G.; Kneyber, Martin C. J.

    Objectives: Transfusion of red blood cells is increasingly linked with adverse outcomes in critically ill children. We tested the hypothesis that leukocyte-depleted red blood cell transfusions were independently associated with increased development of bloodstream infections, ventilator-associated

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

    Science.gov (United States)

    Sevick, E M; Jain, R K

    1991-05-15

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

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

    Science.gov (United States)

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

    2017-09-01

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

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

    Science.gov (United States)

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

    2016-05-06

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

  6. Cobalt uptake and binding in human red blood cells.

    Science.gov (United States)

    Simonsen, Lars Ole; Brown, Anthony M; Harbak, Henrik; Kristensen, Berit I; Bennekou, Poul

    2011-04-15

    is not observed in the case of (54)Mn. Tightly bound and the major part of reversibly bound (57)Co co-migrate with hemoglobin in Sephadex column chromatography of a lysate of (57)Co-loaded cells. (57)Co also co-migrates with hemoglobin when added to a lysate of unlabeled cells or to a solution of purified hemoglobin, in both cases with a time-dependent development of tight binding. Cobalt is known to bind to the globin moiety of hemoglobin. The results imply that during long-term cobalt exposure in vivo cobalt will be taken up practically irreversibly in the red cells during their 120 days life span. Thus, for biomonitoring of cobalt exposure, it could be appropriate to measure the cobalt content in red cells to give, compared with timed or in-competition whole-blood and serum analysis, an average value for the exposure over the last couple of months.

  7. Red blood cells transfusions in oncological patients treated with radio- and chemoterapy

    Directory of Open Access Journals (Sweden)

    Antić Ana

    2011-01-01

    Full Text Available Background/Aim. Anemia is one of the most frequent hematology disorders in patients with malignant diseases. It has a great influence on reduction of the quality of life, so it requires early diagnosis and an adequate treatment. The aim of this study was to present and analyze the treatment of anemia using red blood cell transfusions in patients with malignancies, to analyze adequate use of red blood cell transfusions according to hemoglobin concentration, and also the influence of the treatment of malignant disease on the level of anemia and use of red blood cells transfusion. Methods. This retrospective analysis included the data on the use of red blood cells in Oncological Clinic of Clinical Center Niš in a period from the 1st January 2008 to the 31st December 2008. Results. None of the patients received the whole blood. In this period, 735 patients received 1,006 units of red blood cells (red blood cell concentrate, resuspended, washed, filtered. An average use of red blood cell transfusion was 1.37 unit per oncological patient who received transfusion. The use of red blood cell units was adequate (87.60% of patients received transfusion of red cells when Hgb < 80 g/L. During radio- and chemotherapy we noticed a decrease of hematological parameter values. The patients of the experimental group were dependant on red blood cells transfusion. Statistically, a significant decrease of hemoglobin level was observed in patients treated only with radiotherapy who are the greatest consumers of red blood cells. Two patients were registered who more likely to have febrile nonhemolytic transfusion reactions. Posttransfusion alloimmunization occurred in 0.68% of the patients. Conclusion. The use of red blood cells in oncological patients is in compliance with the up to date tendencies and recommendations published in clinical guidelines. For the purpose of efficient transfusion support in patients with malignant diseases, we have to follow the newest

  8. On the shape memory of red blood cells

    Science.gov (United States)

    Cordasco, Daniel; Bagchi, Prosenjit

    2017-04-01

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

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

    CERN Document Server

    Wang, Tong; 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-dimensionalmotions 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 posit...

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

    Science.gov (United States)

    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.

  11. Photodynamic effects of protoporphyrin on the architecture of erythrocyte membranes in protoporphyria and in normal red blood cells

    NARCIS (Netherlands)

    Goeij, A.F.P.M.; Vergaert, P.H.J.Th ver; Steveninck, J. van

    1975-01-01

    Protoporphyrin causes a photodynamic damage of the red blood cell membrane. After illumination of red blood cells in the presence of protoporphyrin three effects can be observed: 1. 1. Red blood cell membranes show particle aggregation on the outer and inner fracture face, as seen in freeze-etch e

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

    NARCIS (Netherlands)

    Dinkla, S.; Peppelman, M.; Raadt, J. van der; Atsma, F.; Novotny, V.M.J.; Kraaij, M.G.J. van; Joosten, I.; Bosman, G.J.C.G.M.

    2014-01-01

    BACKGROUND: Exposure of phosphatidylserine on the outside of red blood cells contributes to recognition and removal of old and damaged cells. The fraction of phosphatidylserine-exposing red blood cells varies between donors, and increases in red blood cell concentrates during storage. The susceptibi

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

    Science.gov (United States)

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

    2013-01-01

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

  14. Natural Antioxidants Improve Red Blood Cell “Survival” in Non-Leukoreduced Blood Samples

    Directory of Open Access Journals (Sweden)

    Yuliya V Kucherenko

    2015-03-01

    Full Text Available Background: Blood collected in an anticoagulant can be kept refrigerated in an unmodified state within 5 - 6 weeks. Oxidative damage is considered to be a one of the major factors contributing to the development of storage lesions. Lipid and membrane proteins oxidation results in changes in cation gradients that affect the cell survival. Aim: In the present study we used the natural antioxidants and ion channels blockers (L-carnosine, spermine, phloretin and their mixtures to prolong “survival” of red blood cells (RBCs, measured as the lack of PS exposure and cell hemolysis, in the Alsever's preservative solution upon hypothermic storage. Results: We show that the mixture of carnosine (20 mM, spermine (20 µM and phloretin (100 µM effectively blunted phosphatidylserine (PS exposure, Ca2+ accumulation and RBCs hemolysis in non-leukoreduced low (∼2% hematocrit samples after 36 days of storage as well as after 1 day of post-storage incubation of the stored cells in physiological saline solution. In addition, a slight but significant decrease in PS exposure was observed in non-leukoreduced high (∼20% hematocrit samples after 36 days of storage with the mixture of substances. Conclusion: We conclude that the use of the mixture of natural antioxidants (carnosine, spermine, and phloretin as an additive to blood preservative solution provides better RBCs storage and “survival”.

  15. Quantitative photoacoustic assessment of red blood cell aggregation under pulsatile blood flow: experimental and theoretical approaches

    Science.gov (United States)

    Bok, Tae-Hoon; Hysi, Eno; Kolios, Michael C.

    2017-03-01

    In the present paper, the optical wavelength dependence on the photoacoustic (PA) assessment of the pulsatile blood flow was investigated by means of the experimental and theoretical approaches analyzing PA radiofrequency spectral parameters such as the spectral slope (SS) and mid-band fit (MBF). For the experimental approach, the pulsatile flow of human whole blood at 60 bpm was imaged using the VevoLAZR system (40-MHz-linear-array probe, 700-900 nm illuminations). For the theoretical approach, a Monte Carlo simulation for the light transmit into a layered tissue phantom and a Green's function based method for the PA wave generation was implemented for illumination wavelengths of 700, 750, 800, 850 and 900 nm. The SS and MBF for the experimental results were compared to theoretical ones as a function of the illumination wavelength. The MBF increased with the optical wavelength in both theory and experiments. This was expected because the MBF is representative of the PA magnitude, and the PA signal from red blood cell (RBC) is dependent on the molar extinction coefficient of oxyhemoglobin. On the other hand, the SS decreased with the wavelength, even though the RBC size (absorber size which is related to the SS) cannot depend on the illumination wavelength. This conflicting result can be interpreted by means of the changes of the fluence pattern for different illumination wavelengths. The SS decrease with the increasing illumination wavelength should be further investigated.

  16. Spring-network-based model of a red blood cell for simulating mesoscopic blood flow.

    Science.gov (United States)

    Nakamura, Masanori; Bessho, Sadao; Wada, Shigeo

    2013-01-01

    We developed a mechanical model of a red blood cell (RBC) that is capable of expressing its characteristic behaviors in shear flows. The RBC was modeled as a closed shell membrane consisting of spring networks in the framework of the energy minimum concept. The fluid forces acting on RBCs were modeled from Newton's viscosity law and the conservation of momentum. In a steady shear flow, the RBC model exhibited various behaviors, depending on the shear rate; it tumbled, tank-treaded, or both. The transition from tumbling to tank-treading occurred at a shear rate of 20 s( - 1). The simulation of an RBC in steady and unsteady parallel shear flows (Couette flows) showed that the deformation parameters of the RBC were consistent with experimental results. The RBC in Poiseuille flow migrated radially towards the central axis of the flow channel. Axial migration became faster with an increase in the viscosity of the media, qualitatively consistent with experimental results. These results demonstrate that the proposed model satisfies the essential conditions for simulating RBC behavior in blood flow. Finally, a large-scale RBC flow simulation was implemented to show the capability of the proposed model for analyzing the mesoscopic nature of blood flow.

  17. Application of the ADVIA cerebrospinal fluid assay to count residual red blood cells in blood components.

    Science.gov (United States)

    Culibrk, B; Stone, E; Levin, E; Weiss, S; Serrano, K; Devine, D V

    2012-10-01

    There is no automated, accurate assay for the enumeration of residual red blood cells (rRBCs) in non-RBC components for transfusion, despite the potential risk of allo-immunization when mismatched components are transfused. The automated ADVIA 120 cerebrospinal fluid (CSF) assay, which is approved to count RBCs and WBCs in CSF samples, was optimized and tested to measure rRBC in platelet concentrate (PC) and plasma components. Sample dilution, incubation time and reagent volume were optimized for use with non-RBC blood products. The assay was linear (R(2) = 0·99), even at low rRBCs counts. Intra- and inter-assay variation gave coefficients of variance (CV) between 2·2 and 9·4% and 2·6 and 14·9%, respectively, depending on rRBC levels. Good correlation (r = 0·995) was found between the automated assay and manual counting, which is considered the gold standard. Using the automated assay, the range of rRBCs (count/unit) in buffy-coat platelet concentrate (PCs) was 27-5505 × 10(6) and in apheresis PCs was 1-361 × 10(6). The ADVIA CSF assay is a sensitive, precise and accurate means to assess rRBC counts in non-RBC components. © 2012 The Author(s). Vox Sanguinis © 2012 International Society of Blood Transfusion.

  18. Multiscale modeling of red blood cell mechanics and blood flow in malaria.

    Directory of Open Access Journals (Sweden)

    Dmitry A Fedosov

    2011-12-01

    Full Text Available Red blood cells (RBCs infected by a Plasmodium parasite in malaria may lose their membrane deformability with a relative membrane stiffening more than ten-fold in comparison with healthy RBCs leading to potential capillary occlusions. Moreover, infected RBCs are able to adhere to other healthy and parasitized cells and to the vascular endothelium resulting in a substantial disruption of normal blood circulation. In the present work, we simulate infected RBCs in malaria using a multiscale RBC model based on the dissipative particle dynamics method, coupling scales at the sub-cellular level with scales at the vessel size. Our objective is to conduct a full validation of the RBC model with a diverse set of experimental data, including temperature dependence, and to identify the limitations of this purely mechanistic model. The simulated elastic deformations of parasitized RBCs match those obtained in optical-tweezers experiments for different stages of intra-erythrocytic parasite development. The rheological properties of RBCs in malaria are compared with those obtained by optical magnetic twisting cytometry and by monitoring membrane fluctuations at room, physiological, and febrile temperatures. We also study the dynamics of infected RBCs in Poiseuille flow in comparison with healthy cells and present validated bulk viscosity predictions of malaria-infected blood for a wide range of parasitemia levels (percentage of infected RBCs with respect to the total number of cells in a unit volume.

  19. Cinnamomum zeylanicum extract on the radiolabelling of blood constituents and the morphometry of red blood cells: In vitro assay

    Energy Technology Data Exchange (ETDEWEB)

    Benarroz, M.O. [Instituto de Biologia Roberto Alcantara Gomes, Departamento de Biofisica e Biometria, Universidade do Estado do Rio de Janeiro, Avenida 28 de Setembro, 87, 4o Andar, Vila Isabel, 20551-030 Rio de Janeiro, RJ (Brazil); Universidade Federal do Rio Grande do Norte, Programa de Pos-Graduacao em Ciencias da Saude, Avenida General Gustavo Cordeiro de Farias, s/n, 59010-180 Natal, RN (Brazil); Fonseca, A.S. [Instituto de Biologia Roberto Alcantara Gomes, Departamento de Biofisica e Biometria, Universidade do Estado do Rio de Janeiro, Avenida 28 de Setembro, 87, 4o Andar, Vila Isabel, 20551-030 Rio de Janeiro, RJ (Brazil)], E-mail: adenilso@uerj.br; Rocha, G.S. [Instituto de Biologia Roberto Alcantara Gomes, Departamento de Biofisica e Biometria, Universidade do Estado do Rio de Janeiro, Avenida 28 de Setembro, 87, 4o Andar, Vila Isabel, 20551-030 Rio de Janeiro, RJ (Brazil); Frydman, J.N.G. [Instituto de Biologia Roberto Alcantara Gomes, Departamento de Biofisica e Biometria, Universidade do Estado do Rio de Janeiro, Avenida 28 de Setembro, 87, 4o Andar, Vila Isabel, 20551-030 Rio de Janeiro, RJ (Brazil); Universidade Federal do Rio Grande do Norte, Programa de Pos-Graduacao em Ciencias da Saude, Avenida General Gustavo Cordeiro de Farias, s/n, 59010-180 Natal, RN (Brazil); Rocha, V.C.; Pereira, M.O. [Instituto de Biologia Roberto Alcantara Gomes, Departamento de Biofisica e Biometria, Universidade do Estado do Rio de Janeiro, Avenida 28 de Setembro, 87, 4o Andar, Vila Isabel, 20551-030 Rio de Janeiro, RJ (Brazil)] (and others)

    2008-02-15

    Effects of Cinnamomum zeylanicum (cinnamon) on the labelling of blood constituents with technetium-99 m({sup 99m}Tc) and on the morphology of red blood cells were studied. Blood samples from Wistar rats were incubated with cinnamon extract for 1hour or with 0.9% NaCl, as control. Labelling of blood constituents with {sup 99m}Tc was performed. Plasma (P) and blood cells (BC), soluble (SF-P and SF-BC) and insoluble (IF-P and IF-BC) fractions were separated. The radioactivity in each fraction was counted and the percentage of radioactivity incorporated (%ATI) was calculated. Blood smears were prepared, fixed, stained and the qualitative and quantitative morphological analysis of the red blood cells was evaluated. The data showed that the cinnamon extract decreased significantly (p<0.05) the %ATI on BC, IF-P and IF-BC. No modifications were verified on shape of red blood cells. Cinnamon extracts could alter the labelling of blood constituents with {sup 99m}Tc, and although our results were obtained with animals, precaution is suggested in interpretations of nuclear medicine examinations involving the labelling of blood constituents in patients who are using cinnamon.

  20. Geometrical Aspects During Formation of Compact Aggregates of Red Blood Cells

    Directory of Open Access Journals (Sweden)

    Cardoso A.V.

    2002-01-01

    Full Text Available In the past forty years considerable progress has been achieved on the knowledge of human blood as a non-Newtonian shear-thinning suspension, whose initial state, that is at rest (stasis or at very low shear rates, has a gel-like internal structure which is destroyed as shear stress increases. The main goal of this communication is to describe the role of geometrical aspects during RBC (red blood cell aggregate formation, growth and compaction on naturally aggregate (porcine blood and non-aggregate (bovine blood samples. We consider how these aspects coupled with tension equilibrium are decisive to transform red cell linear roleaux to three-dimensional aggregates or clusters. Geometrical aspects are also crucial on the compaction of red blood cell aggregates. These densely packed aggregates could precipitate out of blood- either as dangerous deposits on arterial walls, or as clots which travel in suspension until they block some crucial capillary.

  1. Lattice Boltzmann Simulation of Healthy and Defective Red Blood Cell Settling in Blood Plasma.

    Science.gov (United States)

    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.

  2. Research opportunities in loss of red blood cell mass in space flight

    Science.gov (United States)

    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.

  3. Recurrent thymoma with stiff-person syndrome and pure red blood cell aplasia.

    Science.gov (United States)

    Kobayashi, Rei; Kaji, Masahiro; Horiuchi, Sho; Miyahara, Naofumi; Hino, Yumi; Suemasu, Keiichi

    2014-05-01

    Stiff-person syndrome (formerly known as stiff-man syndrome) is a very rare autoimmune and neurogenic disorder, thought to present as a paraneoplastic variant in association with thymoma. Pure red blood cell aplasia is also a paraneoplastic disorder associated with thymoma. Although separate cases of stiff-person syndrome and pure red blood cell aplasia have been reported, we describe here what is to our knowledge the first case of recurrent thymoma with both stiff-person syndrome and pure red blood cell aplasia. We describe the successful treatment of the neurogenic symptoms of stiff-person syndrome and the progressive anemia associated with pure red blood cell aplasia by tumor excision.

  4. Safety Evaluation of Hemoglobin-Albumin Cluster "HemoAct" as a Red Blood Cell Substitute

    National Research Council Canada - National Science Library

    Haruki, Risa; Kimura, Takuya; Iwasaki, Hitomi; Yamada, Kana; Kamiyama, Ikuo; Kohno, Mitsutomo; Taguchi, Kazuaki; Nagao, Saori; Maruyama, Toru; Otagiri, Masaki; Komatsu, Teruyuki

    2015-01-01

    A hemoglobin (Hb) wrapped covalently by human serum albumins (HSAs), a core-shell structured hemoglobin-albumin cluster designated as "HemoAct", is an O2-carrier designed for use as a red blood cell (RBC) substitute...

  5. A new dihydrochalcone from dragon's blood, red resin of Dracaena cochinchinensis.

    Science.gov (United States)

    Yong, Ke-Lan; Lv, Jing-Ci; Zhang, Tian-Bao; Xu, Lu-Rong; Chen, Xu

    2008-12-01

    A new dihydrochalcone, 4'-hydroxy-4,2'-dimethoxy-dihydrochalcone, was isolated from Chinese dragon's blood, the red resin of Dracaena cochinchinensis. Its structure was established by spectrum analysis.

  6. Acute iatrogenic polycythemia induced by massive red blood cell transfusion during subtotal abdominal colectomy

    Directory of Open Access Journals (Sweden)

    David Chiapaikeo

    2015-03-01

    Full Text Available A 46 year old man was transfused ten units of packed red blood cells during subtotal colectomy after intraoperative point-of-care testing values demonstrated hemoglobin values less than seven grams per deciliter (g/dL. A post-operative hemoglobin analyzed in a standard hematologic laboratory revealed a hemoglobin value of 27.8 g/dL. He underwent emergent red blood cell depletion therapy which decreased his hemoglobin to 7.5 g/dL. The physiologic consequences of iatrogenic polycythemia caused by massive transfusion during major abdominal surgery must take into account the fluid shifts that interplay between the osmotic load, viscosity of blood, and postoperative third spacing of fluid. Treatment of acute iatrogenic polycythemia can be effectively accomplished by red blood cell depletion therapy. However, fluid shifts caused by massive transfusion followed by rapid red cell depletion produce a unique physiologic state that is without a well-described algorithm for management.

  7. Safe extension of red blood cell storage life at 4{degree}C

    Energy Technology Data Exchange (ETDEWEB)

    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. Perturbation of red blood cell membrane rigidity by extracellular ligands.

    Science.gov (United States)

    Paulitschke, M; Nash, G B; Anstee, D J; Tanner, M J; Gratzer, W B

    1995-07-01

    It is known that binding of extracellular antibodies against the major sialoglycoprotein, glycophorin A, reduced the deformability of the red blood cell membrane. This has been taken to result from new or altered interactions between the glycophorin A and the membrane skeleton. We have shown by means of the micropipette aspiration technique that antibodies against the preponderant transmembrane protein, band 3, induce similar effects. A definite but much smaller reduction in elasticity of the membrane is engendered by univalent Fab fragments of the anti-band 3 antibodies. By examining cells genetically devoid of glycophorin A or containing a variant of this constituent, truncated at the inner membrane surface, we have shown that the anti-band 3 antibodies do not act through the band 3-associated glycophorin A. We examined the effect of anti-glycophorin A antibodies on homozygous Wr(a+b-) cells, in which an amino acid replacement in band 3 annihilates the Wright b (Wrb) epitope (comprising sequence elements of glycophorin A and band 3) and thus, by implication disrupts or perturbs the band 3-glycophorin A interaction; these cells show a much smaller response to an anti-glycophorin A antibody than do normal controls. We infer that in this case anti-glycophorin A antibodies exert their rigidifying effect through the associated band 3. Another anti-glycophorin A antibody, directed against an epitope remote from the membrane surface, however, increases the rigidity of both Wr(a+b-) and normal cells. This implies that not all antibodies act in the same manner in modifying the membrane mechanical properties. The effect exerted by anti-band 3 antibodies appears not to be transmitted through the band 3-ankyrin-spectrin pathway because the rigidifying effect of the intact antibody persists at alkaline pH, at which there is evidence that the ankyrin-band 3 link is largely dissociated. The large difference between the effects of saturating concentrations of the divalent and

  9. Characterization of Microvesicles Released from Human Red Blood Cells

    Directory of Open Access Journals (Sweden)

    Duc Bach Nguyen

    2016-03-01

    Full Text Available Background/Aims: Extracellular vesicles (EVs are spherical fragments of cell membrane released from various cell types under physiological as well as pathological conditions. Based on their size and origin, EVs are classified as exosome, microvesicles (MVs and apoptotic bodies. Recently, the release of MVs from human red blood cells (RBCs under different conditions has been reported. MVs are released by outward budding and fission of the plasma membrane. However, the outward budding process itself, the release of MVs and the physical properties of these MVs have not been well investigated. The aim of this study is to investigate the formation process, isolation and characterization of MVs released from RBCs under conditions of stimulating Ca2+ uptake and activation of protein kinase C. Methods: Experiments were performed based on single cell fluorescence imaging, fluorescence activated cell sorter/flow cytometer (FACS, scanning electron microscopy (SEM, atomic force microscopy (AFM and dynamic light scattering (DLS. The released MVs were collected by differential centrifugation and characterized in both their size and zeta potential. Results: Treatment of RBCs with 4-bromo-A23187 (positive control, lysophosphatidic acid (LPA, or phorbol-12 myristate-13 acetate (PMA in the presence of 2 mM extracellular Ca2+ led to an alteration of cell volume and cell morphology. In stimulated RBCs, exposure of phosphatidylserine (PS and formation of MVs were observed by using annexin V-FITC. The shedding of MVs was also observed in the case of PMA treatment in the absence of Ca2+, especially under the transmitted bright field illumination. By using SEM, AFM and DLS the morphology and size of stimulated RBCs, MVs were characterized. The sizes of the two populations of MVs were 205.8 ± 51.4 nm and 125.6 ± 31.4 nm, respectively. Adhesion of stimulated RBCs and MVs was observed. The zeta potential of MVs was determined in the range from - 40 mV to - 10 m

  10. Lowering of blood pressure by increasing hematocrit with non nitric oxide scavenging red blood cells.

    Science.gov (United States)

    Salazar Vázquez, Beatriz Y; Cabrales, Pedro; Tsai, Amy G; Johnson, Paul C; Intaglietta, Marcos

    2008-02-01

    Isovolemic exchange transfusion of 40% of the blood volume in awake hamsters was used to replace native red blood cells (RBCs) with RBCs whose hemoglobin (Hb) was oxidized to methemoglobin (MetHb), MetRBCs. The exchange maintained constant blood volume and produced different final hematocrits (Hcts), varying from 48 to 62% Hct. Mean arterial pressure (MAP) did not change after exchange transfusion, in which 40% of the native RBCs were replaced with MetRBCs, without increasing Hct. Increasing Hct with MetRBCs lowered MAP by 12 mm Hg when Hct was increased 12% above baseline. Further increases of Hct with MetRBCs progressively returned MAP to baseline, which occurred at 62% Hct, a 30% increase in Hct from baseline. These observations show a parabolic "U" shaped distribution of MAP against the change in Hct. Cardiac index, cardiac output divided by body weight, increased between 2 and 17% above baseline for the range of Hcts tested. Peripheral vascular resistance (VR) was decreased 18% from baseline when Hct was increased 12% from baseline. VR and MAP were above baseline for increases in Hct higher than 30%. However, vascular hindrance, VR normalized by blood viscosity (which reflects the contribution of vascular geometry), was lower than baseline for all the increases in Hct tested with MetRBC, indicating prevalence of vasodilation. These suggest that acute increases in Hct with MetRBCs increase endothelium shear stress and stimulate the production of vasoactive factors (e.g., nitric oxide [NO]). When MetRBCs were compared with functional RBCs, vasodilation was augmented for MetRBCs probably due to the lower NO scavenging of MetHb. Consequently, MetRBCs increased the viscosity related hypotension range compared with functional RBCs as NO shear stress vasodilation mediated responses are greater.

  11. NHE-1 sequence and expression in toad, snake and fish red blood cells

    DEFF Research Database (Denmark)

    Thomsen, Steffen Nyegaard; Wang, Tobias; Kristensen, Torsten

    Red blood cells (RBC) from reptiles appear not to express regulatory volume increase (RVI) upon shrinkage (Kristensen et al., 2008). In other vertebrates, the RVI response is primarily mediated by activation of the Na+/H+ exchanger (NHE-1) and we, therefore decided to investigate whether red cell...

  12. The mode of action of some antibiotics on red blood cell membranes.

    Science.gov (United States)

    Blaskó, K; Shagina, L V; Györgyi, S; Lev, A A

    1986-12-01

    Data are presented on the interaction of gramicidin, primycin and valinomycin with red blood cell membranes and compared with those obtained for artificial lipid bilayer membranes. The channel forming antibiotics gramicidin and primycin show specific kinetic behaviour in living cell membranes. It could be shown that the penetration of these antibiotics into the red blood cell membrane is a cooperative process resulting in the occurrence of aggregates in the lipid lattice of the membrane.

  13. Dynamical Modes of Deformed Red Blood Cells and Lipid Vesicles in Flows

    Science.gov (United States)

    Noguchi, H.

    Red blood cells and lipid vesicles exhibit rich behaivor in flows.Their dynamics were studied using a particle-based hydrodynamic simulation method, multi-particle collision dynamics. Rupture of lipid vesicles in simple shear flow was simulated by meshless membrane model. Several shape transitions of lipid vesicles and red blood cells are induced by flows. Transition of a lipid vesicle from budded to prolate shapes with increasing shear rate and ordered alignments of deformed elastic vesicles in high density are presented.

  14. Estimated red blood cell thickness in microcytic anemia due to iron deficiency anemia and thalassemia

    Directory of Open Access Journals (Sweden)

    Viroj Wiwanitkit

    2009-05-01

    Full Text Available "nAnemia is one of the most common hematological disorders that are still the present in all countries around the world. Microcytic anemia is a specific kind of anemia presenting with small red blood cell. In this paper, the author discusses on the estimated red blood cell thickness, a new proposed parameter, comparing between that of iron deficiency anemia and thalassemia and further extrapolate on the clinical implication.

  15. Duration of red blood cell storage and survival of transfused patients (CME)

    DEFF Research Database (Denmark)

    Edgren, Gustaf; Kamper-Jørgensen, Mads; Eloranta, Sandra;

    2010-01-01

    Disquieting reports of increased complication and death rates after transfusions of red blood cells (RBCs) stored for more than 14 days prompted us to perform an observational retrospective cohort study of mortality in relation to storage time.......Disquieting reports of increased complication and death rates after transfusions of red blood cells (RBCs) stored for more than 14 days prompted us to perform an observational retrospective cohort study of mortality in relation to storage time....

  16. Seventy-five genetic loci influencing the human red blood cell

    OpenAIRE

    van der Harst, Pim; Zhang, Weihua; Mateo Leach, Irene; Rendon, Augusto; Verweij, Niek; Sehmi, Joban; Dirk S Paul; Elling, Ulrich; Allayee, Hooman; Li, Xinzhong; Radhakrishnan, Aparna; Tan, Sian-Tsung; Voss, Katrin; Weichenberger, Christian X.; Albers, Cornelis A

    2012-01-01

    Anaemia is a chief determinant of global ill health, contributing to cognitive impairment, growth retardation and impaired physical capacity. To understand further the genetic factors influencing red blood cells, we carried out a genome-wide association study of haemoglobin concentration and related parameters in up to 135,367 individuals. Here we identify 75 independent genetic loci associated with one or more red blood cell phenotypes at P < 10(-8), which together explain 4-9% of the phe...

  17. Impairments in the Nanostructure of Red Blood Cell Membranes in Acute Blood Loss and Their Correction with Perfluorocarbon Emulsion

    Directory of Open Access Journals (Sweden)

    V. V. Moroz

    2011-01-01

    Full Text Available Objective: to study impairments in the nanostructure of red blood cell membranes in acute blood loss and methods to correct the membrane structures with perfluorocarbon emulsion. Materials and methods. Experiments were carried out on Nembutal-anesthesized outbred rats. The model of a terminal state was 60-minute hypovolemic hypotension, followed by blood reinfusion and addition of perfluorane or Ringer’s solution. Images of fragments of the red blood cell membrane surface structure were obtained using a Femtoscan atomic force microscope (AFM. Twenty-seven experiments were performed; 186 cells were scanned on the AFM, which provided 720 images of three orders. Results. The paper shows the time course of changes in the index hi for different phases of an experiment. After 5-minute hypotension, h1 increased by more than 4.3 times and after 60-minute hypotension, this value decreased to 4.7 nm. The second-order height rose linearly at the stages: control — at 5 minutes — at 60 minutes of hypotension. At 60 minutes of hypotension, the first- and second-order heights were similar. At 5 minutes of hypotension, the third-order surface slightly changed — it increased by 1.5-fold. But at 60 minutes of hypotension, the changes in the fine structures of the membrane became great — h3 increased by 6.3 times. Conclusion. Blood loss has shown to induce impairments in the microstructure of red blood cell membranes at all levels of its organization: flick in the range of 600—1000 nm, spectrin matrix at 150—350 nm, proteins, band 3, at 30—80 nm. The per-fluorocarbon emulsion «Perftoran» exerts a pronounced modulatory effect on the red blood cell membrane nanostructure at all steps of its organization, by restoring the membrane nanostructure practically to the control level. Key words: blood loss, red blood cell membrane, nanostructure, atomic force microscopy.

  18. Effects of Aged Stored Autologous Red Blood Cells on Human Endothelial Function

    Science.gov (United States)

    Kanias, Tamir; Triulzi, Darrel; Donadee, Chenell; Barge, Suchitra; Badlam, Jessica; Jain, Shilpa; Belanger, Andrea M.; Kim-Shapiro, Daniel B.

    2015-01-01

    Rationale: A major abnormality that characterizes the red cell “storage lesion” is increased hemolysis and reduced red cell lifespan after infusion. Low levels of intravascular hemolysis after transfusion of aged stored red cells disrupt nitric oxide (NO) bioavailabity, via accelerated NO scavenging reaction with cell-free plasma hemoglobin. The degree of intravascular hemolysis post-transfusion and effects on endothelial-dependent vasodilation responses to acetylcholine have not been fully characterized in humans. Objectives: To evaluate the effects of blood aged to the limits of Food and Drug Administration–approved storage time on the human microcirculation and endothelial function. Methods: Eighteen healthy individuals donated 1 U of leukopheresed red cells, divided and autologously transfused into the forearm brachial artery 5 and 42 days after blood donation. Blood samples were obtained from stored blood bag supernatants and the antecubital vein of the infusion arm. Forearm blood flow measurements were performed using strain-gauge plethysmography during transfusion, followed by testing of endothelium-dependent blood flow with increasing doses of intraarterial acetylcholine. Measurements and Main Results: We demonstrate that aged stored blood has higher levels of arginase-1 and cell-free plasma hemoglobin. Compared with 5-day blood, the transfusion of 42-day packed red cells decreases acetylcholine-dependent forearm blood flows. Intravascular venous levels of arginase-1 and cell-free plasma hemoglobin increase immediately after red cell transfusion, with more significant increases observed after infusion of 42-day-old blood. Conclusions: We demonstrate that the transfusion of blood at the limits of Food and Drug Administration–approved storage has a significant effect on the forearm circulation and impairs endothelial function. Clinical trial registered with www.clinicaltrials.gov (NCT 01137656) PMID:26222884

  19. Red blood cells inhibit tumour cell adhesion to the peritoneum

    NARCIS (Netherlands)

    M.E.E. van Rossen (Marie Elma); M.P.O. Stoop (M. P O); L.J. Hofland (Leo); P.M. van Koetsveld (Peter); F. Bonthuis (Fred); J. Jeekel (Hans); R.L. Marquet (Richard); C.H.J. van Eijck (Casper)

    1999-01-01

    textabstractBackground: Perioperative blood transfusion has been associated with increased tumour recurrence and poor prognosis in colorectal cancer. Blood loss in the peritoneal cavity might be a tumour-promoting factor for local recurrence. The aim of this study was to investigate whether blood in

  20. Why and how does collective red blood cells motion occur in the blood microcirculation?

    Science.gov (United States)

    Ghigliotti, Giovanni; Selmi, Hassib; Asmi, Lassaad El; Misbah, Chaouqi

    2012-10-01

    The behaviour of red blood cells (RBCs), modelled as vesicles, in Poiseuille flow, mimicking the microvasculature, is studied with numerical simulations in two dimensions. RBCs moving in the centre of the Poiseuille flow (as in blood capillaries) are shown to attract each other and form clusters only due to hydrodynamic interactions, provided that their distance at a given time is below a certain critical value. This distance depends on physical parameters, such as the flow strength. Our simulations reveal that clusters are unstable above a threshold value in the number of forming RBCs, beyond which one or few cells escape the pack by a self-regulating mechanism that select the marginally stable size. This size selection depends on the flow strength as well as on the RBC swelling ratio. The results are interpreted via the analysis of the perturbation of the flow field induced by the vesicles and the interplay with bending and tension forces. This sheds a novel light on the process of collective motion of RBCs observed in vivo.

  1. Effects of Cinnamomum zeylanicum treatment on radiolabeling of blood constituents and morphology of red blood cells in Wistar rats

    Energy Technology Data Exchange (ETDEWEB)

    Benarroz, Monica Oliveira; Fonseca, Adenilson de Souza da; Bernardo-Filho, Mario [Universidade do Estado do Rio de Janeiro (UERJ), RJ (Brazil). Dept. de Biofisica e Biometria]. E-mail: adenilso@uerj.br; Rocha, Gabrielle de Souza; Pereira, Marcia Oliveira [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil); Geller, Mauro [Centro Universitario Serra dos Orgaos, Teresopolis, RJ (Brazil). Centro de Ciencias da Saude; Presta, Giuseppe Antonio [Universidade Federal do Estado do Rio de Janeiro (UNIRIO), Rio de Janeiro, RJ (Brazil). Inst. Biomedico. Dept. de Fisiologia Humana

    2008-12-15

    The aim of this study was to evaluate the effect of in vivo treatment with an aqueous cinnamon extract on the labeling of blood constituents with {sup 99m}Tc and on the morphology of red blood cells from Wistar rats. Animals were treated with cinnamon extract at different doses and for different periods of time. As controls, animals treated with 0.9% NaCl. Labeling of blood constituents with {sup 99}mTc was performed. Plasma, blood cells and insoluble fractions were isolated. Radioactivity in each fraction was counted and the percentage of radioactivity (%ATI) was calculated. Also, blood smears were prepared to morphological analysis of red blood cells from. Data showed that in vivo cinnamon extract did not significantly (p>0.05) modify the %ATI of blood constituents and morphology of red blood cells. The results suggest that in vivo aqueous cinnamon could not affect the membrane structures involved in transport of ions or the oxidation state of stannous and pertechnetate ions. (author)

  2. MEASUREMENT OF REGIONAL BONE BLOOD FLOW IN THE CANINE MANDIBULAR RAMUS USING RADIOLABELLED TOAD RED BLOOD CELLS

    Institute of Scientific and Technical Information of China (English)

    毛驰; 王翰章

    1994-01-01

    Toad red blood cells were used to measure regional bone blood flow in the canine mandibular ramus.The blood cells were labelled with sodium pertechnetate and fixed in 10% formalin;they were 22×15 μm in size and had a specific gravity close to that of dog red blood cells.These cells had no discernible effect on systemic hemody-namics after injection,did not agglutinate,were well mixed and evenly distributed throughout the body,and were completely extracted in one circulation through the mandible.The mandibular ramus was divided into six regions,and the blood flow rates in each were found to be similar to those reported in previous studies with radiolabelled carbonized,microspheres.Furthermore,the blood flow distribution pattern of the mandibular ramus determined in this study was identical to that of our previous study using the bone-seeking radionuclide method.We suggest that radiolabelled toad red blood cells are an ideal marker for measuring regional blood flow in the canine mandible.

  3. Blood analyte sensing using fluorescent dye-loaded red blood cells

    Science.gov (United States)

    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.

  4. Comparison of instruments for investigation of microcirculatory blood flow and red blood cell concentration

    Science.gov (United States)

    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

  5. Radiolabeled red blood cells: status, problems, and prospects

    Energy Technology Data Exchange (ETDEWEB)

    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.

  6. Early alterations of red blood cell rheology in critically ill patients.

    Science.gov (United States)

    Reggiori, Giulia; Occhipinti, Giovanna; De Gasperi, Andrea; Vincent, Jean-Louis; Piagnerelli, Michael

    2009-12-01

    To investigate red blood cell rheology in a large intensive care unit population on admission, and to assess the possible influence of comorbidities on the rheology. : Prospective study. Medico-surgical intensive care unit with 31 beds. All intensive care unit admissions during a 5-month period and 20 healthy volunteers. Blood sampling. A total of 196 intensive care patients (160 without and 36 with sepsis) and 20 healthy volunteers were studied. Red blood cell rheology (deformability and aggregation) was assessed ex vivo using the laser-assisted optical rotational cell analyzer (LORCA; Mechatronics Instruments BV, AN Zwaag, Netherlands) within the first 24 hrs after intensive care unit admission. Red blood cell deformability was determined by the elongation index in relation to the shear stress (0.3 to 50 Pa) applied on the red blood cell membrane surface. Aggregation was assessed by the aggregation index. Septic patients were more likely to have anemia, coagulation abnormalities, and comorbidities than were nonseptic patients. Red blood cell deformability was significantly altered in septic compared to nonseptic patients and volunteers for the majority of shear stress rates studied. The aggregation index was greater in septic patients than in volunteers (67.9% [54.7-73.5] vs. 61.8% [58.2-68.4]; p < .05). Only sepsis and hematologic disease influenced the elongation index (both p < .01). Other comorbidities, like cancer, diabetes mellitus, cirrhosis, and terminal renal failure, had no effect on the elongation index. Aggregation index was related to the degree of organ failure (Sequential Organ Failure Assessment score), the red blood cell count, and fibrinogen concentrations. Early alterations of red blood cell rheology are common in intensive care unit patients, especially in those with sepsis. Comorbidities (other than hematologic diseases) do not significantly influence these abnormalities. These alterations could contribute to the microcirculatory alterations

  7. Oxygenated-blood colour change thresholds for perceived facial redness, health, and attractiveness.

    Directory of Open Access Journals (Sweden)

    Daniel E Re

    Full Text Available 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.

  8. Rudimentary study on humanization of porcine red blood cells: Enzymatic removal of galactose-α1,3-galactose antigen from porcine red blood cell

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The serological and biochemical characterization of porcine red blood cells (pRBCs) are similar to human red blood cells. Porcine erythrocytes are considered as an alternative source for human blood transfusion. But there exist galactose-α1,3-galactose antigens (Galα1,3Galβ1, 4GalNAc-R, abbreviated αGal antigen) on pRBCs, which can induce anti-(Gal antibodies in human serum. The (Galepitopes are the major antigen responsible for hyperacute rejection in xenotransfusion. In this study, recombined soybean α-galactosidase (rSα-GalE) was usedto remove the (Gal antigens from pPRCs for humanization. The results showed that (Gal antigen was cleared by rSα-GalE and the structure and function of rSα-GalE treated pRBC were normal.

  9. Biological effects of the electrostatic field: red blood cell-related alterations of oxidative processes in blood

    Science.gov (United States)

    Harutyunyan, Hayk A.; Sahakyan, Gohar V.

    2016-01-01

    The aim of this study was to determine activities of pro-/antioxidant enzymes, reactive oxygen species (ROS) content, and oxidative modification of proteins and lipids in red blood cells (RBCs) and blood plasma of rats exposed to electrostatic field (200 kV/m) during the short (1 h) and the long periods (6 day, 6 h daily). Short-term exposure was characterized by the increase of oxidatively damaged proteins in blood of rats. This was strongly expressed in RBC membranes. After long-term action, RBC content in peripheral blood was higher than in control ( P < 0.01) and the attenuation of prooxidant processes was shown.

  10. Cobalt uptake and binding in human red blood cells

    DEFF Research Database (Denmark)

    Simonsen, Lars Ole; Brown, Anthony M; Harbak, Henrik

    2011-01-01

    The basal uptake and cytoplasmic binding of cobalt was studied in human red cells using (57)Co as tracer. The basal uptake is linear with time, at a rate of about 10 µmol (l cells)(-1) h(-1) at 100 µM [Co(2+)](o), and is almost irreversible, as there is hardly any efflux into excess EDTA. Ionophore...

  11. Storage-induced increase in biomarkers of oxidative stress and inflammation in red blood cell components

    DEFF Research Database (Denmark)

    Kücükakin, Bülent; Kocak, Volkan; Lykkesfeldt, Jens;

    2011-01-01

    Background. Transfusion of blood components may increase the risk of complications in relation to surgery. During storage, red blood cells (RBCs) undergo structural and functional changes that may reduce function and viability after transfusion. The aim of the study was to evaluate the quality...

  12. Historical time trends in red blood cell usage in the Netherlands

    NARCIS (Netherlands)

    van Hoeven, Loan R; Koopman, Maria M W; Koffijberg, Hendrik; Roes, Kit C.B.; Janssen, Mart P

    2016-01-01

    Background: While the number of hospitalized patients in Dutch hospitals has increased since 1997, the demand for red blood cell units (RBCs) has simultaneously decreased. This implies a dramatic change in transfusion practice toward fewer blood transfusions on average per patient. Objectives: In or

  13. Haemolysis following rapid experimental red blood cell transfusion--an evaluation of two infusion pumps

    DEFF Research Database (Denmark)

    Hansen, Tom Giedsing; Sprogøe-Jakobsen, U; Pedersen, C M;

    1998-01-01

    The vast majority of infusion pumps used for rapid transfusion of large amounts of blood have never been properly examined regarding their influence on the quality of the red blood cells (RBCs) infused. In this study, we evaluated the effect of two different infusion pumps on the degree of RBC...

  14. Haemolysis following rapid experimental red blood cell transfusion--an evaluation of two infusion pumps

    DEFF Research Database (Denmark)

    Hansen, Tom Giedsing; Sprogøe-Jakobsen, U; Pedersen, C M

    1998-01-01

    The vast majority of infusion pumps used for rapid transfusion of large amounts of blood have never been properly examined regarding their influence on the quality of the red blood cells (RBCs) infused. In this study, we evaluated the effect of two different infusion pumps on the degree of RBC de...

  15. Flow structures and red blood cell dynamics in arteriole of dilated or constricted cross section.

    Science.gov (United States)

    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.

  16. Mechanical and electrical properties of red blood cells using optical tweezers

    Science.gov (United States)

    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.

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

    CERN Document Server

    Brust, M; Thiebaud, 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 pers...

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

    Science.gov (United States)

    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.

  19. Ex-vivo expansion of red blood cells: How real for transfusion in humans?

    OpenAIRE

    Migliaccio, Anna Rita; Masselli, Elena; Varricchio, Lilian; Whitsett, Carolyn

    2011-01-01

    Blood transfusion is indispensable for modern medicine. In developed countries, the blood supply is adequate and safe but blood for alloimmunized patients is often unavailable. Concerns are increasing that donations may become inadequate in the future as the population ages prompting a search for alternative transfusion products. Improvements in culture conditions and proof-of-principle studies in animal models have suggested that ex-vivo expanded red cells may represent such a product. Compa...

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

    Directory of Open Access Journals (Sweden)

    Paula Loureiro

    2014-04-01

    Full Text Available 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.

  1. Storage and survival of red blood cells with elevated sodium levels.

    Science.gov (United States)

    Wallas, C H; Harris, A S; Wetherall, N T

    1982-01-01

    Approximately 25 percent of black blood donors have an elevated red blood cell (RBC) sodium (Nai) level compared with white donors. This elevation results in a significant increase in the mean Nai from black (9.00 +/- 2.96 mmoles/l RBC) as compared to white blood donors (7.04 +/- 1.48 mmoles/l RBC, p less than 0.001). Red blood cells from four black donors with mean Nai levels of 15 +/- 2.8 mmoles/l RBC were stored for 35 days in citrate-phosphate-dextrose-adenine and compared to that of four donors with normal levels of Nai. Serial measurements of red blood cell adenosine triphosphate, diphosphoglycerate, glucose-6-phosphate dehydrogenase, pyruvic kinase, lactate production rates, and intracellular cations showed no differences between the two donor groups. Furthermore, the mean 24-hour posttransfusion survival was not significantly different for the high Nai group (83.2 +/- 5.6%) as compared with the control group (82.3 +/- 6.9%). Based on this study, it is not necessary to eliminate individuals with an elevated red blood cell Nai level as blood donors.

  2. Analysis of Hereditary Elliptocytosis with Decreased Binding of Eosin-5-maleimide to Red Blood Cells

    Directory of Open Access Journals (Sweden)

    Shin-ichiro Suemori

    2015-01-01

    Full Text Available Flow cytometric test for analyzing the eosin-5-maleimide (EMA binding to red blood cells has been believed to be a specific method for diagnosing hereditary spherocytosis (HS. However, it has been reported that diseases other than HS, such as hereditary pyropoikilocytosis (HPP and Southeast Asian ovalocytosis (SAO, which are forms in the category of hereditary elliptocytosis (HE, show decreased EMA binding to red blood cells. We analyzed EMA binding to red blood cells in 101 healthy control subjects and 42 HS patients and obtained a mean channel fluorescence (MCF cut-off value of 36.4 (sensitivity 0.97, specificity 0.95. Using this method, we also analyzed 12 HE patients. Among them, four HE patients showed the MCF at or below the cut-off value. It indicates that some HE patients have decreased EMA binding to red blood cells. Two of these four HE patients were classified as common HE, and two were spherocytic HE with reduced spectrin. This study demonstrates that, in addition to patients with HPP or SAO, some HE patients have decreased EMA binding to red blood cells.

  3. Lidocaine action and conformational changes in cytoskeletal protein network in human red blood cells.

    Science.gov (United States)

    Nishiguchi, E; Hamada, N; Shindo, J

    1995-11-03

    The mechanism of action of lidocaine, which is commonly used clinically as a local anesthetic, was studied in human red blood cells. The influx of [14C]lidocaine through the cell membrane induced reversible transformation of human red blood cells from discocytes to stomatocytes. This change in shape depended on the lidocaine concentration and required both ATP and carbonic anhydrase. The lidocaine-induced shape change occurred as a result of spectrin aggregation, which altered the intracellular environment of the human red blood cells, mediated by carbonic anhydrase and activation of vacuolar type H(+)-ATPase (V-ATPase). Lidocaine controlled the influx of 22Na into the human red blood cells in a concentration-dependent manner. When incubated in media containing 6-chloro-9-[(4-diethylamino)-1-methyl-butyl]amino-2-methoxyacridine (mepacrine), an inhibitor of Na+ channels, human red blood cells changed shape from discocytes to stomatocytes and the intracellular pH decreased. This phenomenon was very similar to the shape change induced by lidocaine. These results suggest that the mode of action of lidocaine is related to a conformational change in the cytoskeletal protein network.

  4. Seventy-five genetic loci influencing the human red blood cell

    Science.gov (United States)

    van der Harst, Pim; Zhang, Weihua; Leach, Irene Mateo; Rendon, Augusto; Verweij, Niek; Sehmi, Joban; Paul, Dirk S.; Elling, Ulrich; Allayee, Hooman; Li, Xinzhong; Radhakrishnan, Aparna; Tan, Sian-Tsung; Voss, Katrin; Weichenberger, Christian X.; Albers, Cornelis A.; Al-Hussani, Abtehale; Asselbergs, Folkert W.; Ciullo, Marina; Danjou, Fabrice; Dina, Christian; Esko, Tõnu; Evans, David M.; Franke, Lude; Gögele, Martin; Hartiala, Jaana; Hersch, Micha; Holm, Hilma; Hottenga, Jouke-Jan; Kanoni, Stavroula; Kleber, Marcus E.; Lagou, Vasiliki; Langenberg, Claudia; Lopez, Lorna M.; Lyytikäinen, Leo-Pekka; Melander, Olle; Murgia, Federico; Nolte, Ilja M.; O’Reilly, Paul F.; Padmanabhan, Sandosh; Parsa, Afshin; Pirastu, Nicola; Porcu, Eleonora; Portas, Laura; Prokopenko, Inga; Ried, Janina S.; Shin, So-Youn; Tang, Clara S.; Teumer, Alexander; Traglia, Michela; Ulivi, Sheila; Westra, Harm-Jan; Yang, Jian; Zhao, Jing Hua; Anni, Franco; Abdellaoui, Abdel; Attwood, Antony; Balkau, Beverley; Bandinelli, Stefania; Bastardot, François; Benyamin, Beben; Boehm, Bernhard O.; Cookson, William O.; Das, Debashish; de Bakker, Paul I. W.; de Boer, Rudolf A.; de Geus, Eco J. C.; de Moor, Marleen H.; Dimitriou, Maria; Domingues, Francisco S.; Döring, Angela; Engström, Gunnar; Eyjolfsson, Gudmundur Ingi; Ferrucci, Luigi; Fischer, Krista; Galanello, Renzo; Garner, Stephen F.; Genser, Bernd; Gibson, Quince D.; Girotto, Giorgia; Gudbjartsson, Daniel Fannar; Harris, Sarah E.; Hartikainen, Anna-Liisa; Hastie, Claire E.; Hedblad, Bo; Illig, Thomas; Jolley, Jennifer; Kähönen, Mika; Kema, Ido P.; Kemp, John P.; Liang, Liming; Lloyd-Jones, Heather; Loos, Ruth J. F.; Meacham, Stuart; Medland, Sarah E.; Meisinger, Christa; Memari, Yasin; Mihailov, Evelin; Miller, Kathy; Moffatt, Miriam F.; Nauck, Matthias; Novatchkova, Maria; Nutile, Teresa; Olafsson, Isleifur; Onundarson, Pall T.; Parracciani, Debora; Penninx, Brenda W.; Perseu, Lucia; Piga, Antonio; Pistis, Giorgio; Pouta, Anneli; Puc, Ursula; Raitakari, Olli; Ring, Susan M.; Robino, Antonietta; Ruggiero, Daniela; Ruokonen, Aimo; Saint-Pierre, Aude; Sala, Cinzia; Salumets, Andres; Sambrook, Jennifer; Schepers, Hein; Schmidt, Carsten Oliver; Silljé, Herman H. W.; Sladek, Rob; Smit, Johannes H.; Starr, John M.; Stephens, Jonathan; Sulem, Patrick; Tanaka, Toshiko; Thorsteinsdottir, Unnur; Tragante, Vinicius; van Gilst, Wiek H.; van Pelt, L. Joost; van Veldhuisen, Dirk J.; Völker, Uwe; Whitfield, John B.; Willemsen, Gonneke; Winkelmann, Bernhard R.; Wirnsberger, Gerald; Algra, Ale; Cucca, Francesco; d’Adamo, Adamo Pio; Danesh, John; Deary, Ian J.; Dominiczak, Anna F.; Elliott, Paul; Fortina, Paolo; Froguel, Philippe; Gasparini, Paolo; Greinacher, Andreas; Hazen, Stanley L.; Jarvelin, Marjo-Riitta; Khaw, Kay Tee; Lehtimäki, Terho; Maerz, Winfried; Martin, Nicholas G.; Metspalu, Andres; Mitchell, Braxton D.; Montgomery, Grant W.; Moore, Carmel; Navis, Gerjan; Pirastu, Mario; Pramstaller, Peter P.; Ramirez-Solis, Ramiro; Schadt, Eric; Scott, James; Shuldiner, Alan R.; Smith, George Davey; Smith, J. Gustav; Snieder, Harold; Sorice, Rossella; Spector, Tim D.; Stefansson, Kari; Stumvoll, Michael; Wilson Tang, W. H.; Toniolo, Daniela; Tönjes, Anke; Visscher, Peter M.; Vollenweider, Peter; Wareham, Nicholas J.; Wolffenbuttel, Bruce H. R.; Boomsma, Dorret I.; Beckmann, Jacques S.; Dedoussis, George V.; Deloukas, Panos; Ferreira, Manuel A.; Sanna, Serena; Uda, Manuela; Hicks, Andrew A.; Penninger, Josef Martin; Gieger, Christian; Kooner, Jaspal S.; Ouwehand, Willem H.; Soranzo, Nicole; Chambers, John C

    2013-01-01

    Anaemia is a chief determinant of globalill health, contributing to cognitive impairment, growth retardation and impaired physical capacity. To understand further the genetic factors influencing red blood cells, we carried out a genome-wide association study of haemoglobin concentration and related parameters in up to 135,367 individuals. Here we identify 75 independent genetic loci associated with one or more red blood cell phenotypes at P <10−8, which together explain 4–9% of the phenotypic variance per trait. Using expression quantitative trait loci and bioinformatic strategies, we identify 121 candidate genes enriched in functions relevant to red blood cell biology. The candidate genes are expressed preferentially in red blood cell precursors, and 43 have haematopoietic phenotypes in Mus musculus or Drosophila melanogaster. Through open-chromatin and coding-variant analyses we identify potential causal genetic variants at 41 loci. Our findings provide extensive new insights into genetic mechanisms and biological pathways controlling red blood cell formation and function. PMID:23222517

  5. Analysis of Hereditary Elliptocytosis with Decreased Binding of Eosin-5-maleimide to Red Blood Cells.

    Science.gov (United States)

    Suemori, Shin-ichiro; Wada, Hideho; Nakanishi, Hidekazu; Tsujioka, Takayuki; Sugihara, Takashi; Tohyama, Kaoru

    2015-01-01

    Flow cytometric test for analyzing the eosin-5-maleimide (EMA) binding to red blood cells has been believed to be a specific method for diagnosing hereditary spherocytosis (HS). However, it has been reported that diseases other than HS, such as hereditary pyropoikilocytosis (HPP) and Southeast Asian ovalocytosis (SAO), which are forms in the category of hereditary elliptocytosis (HE), show decreased EMA binding to red blood cells. We analyzed EMA binding to red blood cells in 101 healthy control subjects and 42 HS patients and obtained a mean channel fluorescence (MCF) cut-off value of 36.4 (sensitivity 0.97, specificity 0.95). Using this method, we also analyzed 12 HE patients. Among them, four HE patients showed the MCF at or below the cut-off value. It indicates that some HE patients have decreased EMA binding to red blood cells. Two of these four HE patients were classified as common HE, and two were spherocytic HE with reduced spectrin. This study demonstrates that, in addition to patients with HPP or SAO, some HE patients have decreased EMA binding to red blood cells.

  6. Seventy-five genetic loci influencing the human red blood cell.

    Science.gov (United States)

    van der Harst, Pim; Zhang, Weihua; Mateo Leach, Irene; Rendon, Augusto; Verweij, Niek; Sehmi, Joban; Paul, Dirk S; Elling, Ulrich; Allayee, Hooman; Li, Xinzhong; Radhakrishnan, Aparna; Tan, Sian-Tsung; Voss, Katrin; Weichenberger, Christian X; Albers, Cornelis A; Al-Hussani, Abtehale; Asselbergs, Folkert W; Ciullo, Marina; Danjou, Fabrice; Dina, Christian; Esko, Tõnu; Evans, David M; Franke, Lude; Gögele, Martin; Hartiala, Jaana; Hersch, Micha; Holm, Hilma; Hottenga, Jouke-Jan; Kanoni, Stavroula; Kleber, Marcus E; Lagou, Vasiliki; Langenberg, Claudia; Lopez, Lorna M; Lyytikäinen, Leo-Pekka; Melander, Olle; Murgia, Federico; Nolte, Ilja M; O'Reilly, Paul F; Padmanabhan, Sandosh; Parsa, Afshin; Pirastu, Nicola; Porcu, Eleonora; Portas, Laura; Prokopenko, Inga; Ried, Janina S; Shin, So-Youn; Tang, Clara S; Teumer, Alexander; Traglia, Michela; Ulivi, Sheila; Westra, Harm-Jan; Yang, Jian; Zhao, Jing Hua; Anni, Franco; Abdellaoui, Abdel; Attwood, Antony; Balkau, Beverley; Bandinelli, Stefania; Bastardot, François; Benyamin, Beben; Boehm, Bernhard O; Cookson, William O; Das, Debashish; de Bakker, Paul I W; de Boer, Rudolf A; de Geus, Eco J C; de Moor, Marleen H; Dimitriou, Maria; Domingues, Francisco S; Döring, Angela; Engström, Gunnar; Eyjolfsson, Gudmundur Ingi; Ferrucci, Luigi; Fischer, Krista; Galanello, Renzo; Garner, Stephen F; Genser, Bernd; Gibson, Quince D; Girotto, Giorgia; Gudbjartsson, Daniel Fannar; Harris, Sarah E; Hartikainen, Anna-Liisa; Hastie, Claire E; Hedblad, Bo; Illig, Thomas; Jolley, Jennifer; Kähönen, Mika; Kema, Ido P; Kemp, John P; Liang, Liming; Lloyd-Jones, Heather; Loos, Ruth J F; Meacham, Stuart; Medland, Sarah E; Meisinger, Christa; Memari, Yasin; Mihailov, Evelin; Miller, Kathy; Moffatt, Miriam F; Nauck, Matthias; Novatchkova, Maria; Nutile, Teresa; Olafsson, Isleifur; Onundarson, Pall T; Parracciani, Debora; Penninx, Brenda W; Perseu, Lucia; Piga, Antonio; Pistis, Giorgio; Pouta, Anneli; Puc, Ursula; Raitakari, Olli; Ring, Susan M; Robino, Antonietta; Ruggiero, Daniela; Ruokonen, Aimo; Saint-Pierre, Aude; Sala, Cinzia; Salumets, Andres; Sambrook, Jennifer; Schepers, Hein; Schmidt, Carsten Oliver; Silljé, Herman H W; Sladek, Rob; Smit, Johannes H; Starr, John M; Stephens, Jonathan; Sulem, Patrick; Tanaka, Toshiko; Thorsteinsdottir, Unnur; Tragante, Vinicius; van Gilst, Wiek H; van Pelt, L Joost; van Veldhuisen, Dirk J; Völker, Uwe; Whitfield, John B; Willemsen, Gonneke; Winkelmann, Bernhard R; Wirnsberger, Gerald; Algra, Ale; Cucca, Francesco; d'Adamo, Adamo Pio; Danesh, John; Deary, Ian J; Dominiczak, Anna F; Elliott, Paul; Fortina, Paolo; Froguel, Philippe; Gasparini, Paolo; Greinacher, Andreas; Hazen, Stanley L; Jarvelin, Marjo-Riitta; Khaw, Kay Tee; Lehtimäki, Terho; Maerz, Winfried; Martin, Nicholas G; Metspalu, Andres; Mitchell, Braxton D; Montgomery, Grant W; Moore, Carmel; Navis, Gerjan; Pirastu, Mario; Pramstaller, Peter P; Ramirez-Solis, Ramiro; Schadt, Eric; Scott, James; Shuldiner, Alan R; Smith, George Davey; Smith, J Gustav; Snieder, Harold; Sorice, Rossella; Spector, Tim D; Stefansson, Kari; Stumvoll, Michael; Tang, W H Wilson; Toniolo, Daniela; Tönjes, Anke; Visscher, Peter M; Vollenweider, Peter; Wareham, Nicholas J; Wolffenbuttel, Bruce H R; Boomsma, Dorret I; Beckmann, Jacques S; Dedoussis, George V; Deloukas, Panos; Ferreira, Manuel A; Sanna, Serena; Uda, Manuela; Hicks, Andrew A; Penninger, Josef Martin; Gieger, Christian; Kooner, Jaspal S; Ouwehand, Willem H; Soranzo, Nicole; Chambers, John C

    2012-12-20

    Anaemia is a chief determinant of global ill health, contributing to cognitive impairment, growth retardation and impaired physical capacity. To understand further the genetic factors influencing red blood cells, we carried out a genome-wide association study of haemoglobin concentration and related parameters in up to 135,367 individuals. Here we identify 75 independent genetic loci associated with one or more red blood cell phenotypes at P < 10(-8), which together explain 4-9% of the phenotypic variance per trait. Using expression quantitative trait loci and bioinformatic strategies, we identify 121 candidate genes enriched in functions relevant to red blood cell biology. The candidate genes are expressed preferentially in red blood cell precursors, and 43 have haematopoietic phenotypes in Mus musculus or Drosophila melanogaster. Through open-chromatin and coding-variant analyses we identify potential causal genetic variants at 41 loci. Our findings provide extensive new insights into genetic mechanisms and biological pathways controlling red blood cell formation and function.

  7. Low red blood cell levels of deglycating enzymes incolorectal cancer patients

    Institute of Scientific and Technical Information of China (English)

    Maria Notarnicola; Maria Gabriella Caruso; Valeria Tutino; Vito Guerra; Giovanni Misciagna

    2011-01-01

    AIM: To investigate Glyoxalase Ⅰ and fructosamine-3- kinase (FN3K) activity in red blood cells from patients with colorectal adenomas and cancer.METHODS: Thirty three consecutive subjects with one or more histologically confirmed colorectal adenomatous polyps, 16 colorectal cancer patients and a group of 11 control subjects with normal colonoscopy were included in the study. Glyoxalase Ⅰ and FN3K activities were measured in red blood cells using a spectrophotometric and radiometric assay, respectively.RESULTS: A significant reduction in both Glyoxalase Ⅰ and FN3K activity was detected in patients with tumors compared to patients with adenomas and the controls. Erythrocyte Glyoxalase Ⅰ activity in colorectal cancer was approximately 6 times lower than that detected in patients with adenoma (0.022 ± 0.01 mmol/min per milliliter vs 0.128 ± 0.19 mmol/min per milliliter of red blood cells, P = 0.003, Tukey's test). FN3K activity in red blood cells from patients with colon cancer was approximately 2 times lower than that detected in adenomapatients (19.55 ± 6.4 pmol/min per milliliter vs 38.6 ± 31.7 pmol/min per milliliter of red blood cells, P = 0.04, Tukey's test).CONCLUSION: These findings suggest that deglycating enzymes may be involved in the malignant transformation of colon mucosa.

  8. Shear induced diffusion in a red blood cell suspension

    Science.gov (United States)

    Podgorski, Thomas; Grandchamp, Xavier; Srivastav, Aparna; Coupier, Gwennou

    2012-11-01

    In the microcirculation, blood exhibits an inhomogeneous structure which results in the well know Fahraeus-Lindqvist effect : the apparent viscosity decreases when the diameter of the capillary decreases due to the formation of a marginal cell depletion layer (known as plasma skimming). This structure is a consequence of several phenomena, which include i) the migration of cells aways from walls due to lift forces and gradients of shear and ii) shear induced diffusion due to collisions and interactions among cells. We investigated these phenomena through experiments in simple shear and microchannel flows, with dilute suspensions of vesicles and blood cells. Pairwise interactions between suspended objects result in non-linear and flow-dependent diffusion, whose properties have been measured in different experiments for vesicles and blood cells. The injection of a sheet of concentrated blood cell suspension in a microchannel with a rectangular cross-section allows, through the measurement of its widening along the channel, to measure the diffusivity of blood cells, both in the local plane of shear and in the vorticity direction.

  9. Storage time of red blood cells and mortality of transfusion recipients.

    Science.gov (United States)

    Middelburg, Rutger A; van de Watering, Leo M G; Briët, Ernest; van der Bom, Johanna G

    2013-01-01

    Storage of red cells and the associated storage lesion have been suggested to contribute to adverse clinical outcomes. The aim of this study was to investigate whether increasing storage time of red cells is associated with mortality of recipients. From all patients who received red cell transfusions between January 2005 and May 2009, in the Leiden University Medical Center, we selected those who received only-young or only-old red cells, defined as below or above the median storage time. Mortality was compared in a Cox regression model. Subsequently, similar comparisons were made between subgroups with increasing contrast between old and young red cells. Among adult patients, after correction for potential confounders, the hazard ratio of death within 1 year after receiving red cells stored for more than 17 days compared with 17 days or less was 0.98 (95% confidence interval, 0.83-1.2). With increasing contrast, the hazard ratio decreased to 0.56 (95% confidence interval, 0.32-0.97) for red cells stored for more than 24 days compared with less than 10 days. In contrast to what has previously been suggested, we find an almost 2-fold increase in mortality rate after the transfusion of fresh red cells compared with old red cells. Results dependent on analyses chosen and previous studies may not have used optimal analyses. The tendency to demand ever-fresher blood could actually be detrimental for at least some patient groups.

  10. Deformation of Two-Dimensional Nonuniform-Membrane Red Blood Cells Simulated by a Lattice Boltzmann Model

    Institute of Scientific and Technical Information of China (English)

    LI Hua-Bing; JIN Li; QIU Bing

    2008-01-01

    To study two-dimensional red blood cells deforming in a shear flow with the membrane nonuniform on the rigidity and mass, the membrane is discretized into equilength segments. The fluid inside and outside the red blood cell is simulated by the D2Q9 lattice Boltzmann model and the hydrodynamic forces exerted on the membrane from the inner and outer of the red blood cell are calculated by a stress-integration method. Through the global deviation from the curvature of uniform-membrane, we find that when the membrane is nonuniform on the rigidity, the deviation first decreases with the time increases and implies that the terminal profile of the red blood cell is static. To a red blood cell with the mass nonuniform on the membrane, the deviation becomes more large, and the mass distribution affects the profile of the two sides of the flattened red blood cell in a shear flow.

  11. Red blood cell: from its mechanics to its motion in shear flow.

    Science.gov (United States)

    Viallat, A; Abkarian, M

    2014-06-01

    There is a number of publications on red blood cell deformability, that is, on the remarkable cell ability to change its shape in response to an external force and to pass through the narrowest blood capillaries and splenic sinuses. Cell deformability is postulated to be a major determinant of impaired perfusion, increase of blood viscosity, and occlusion in microvessels. Current deformability tests like ektacytometry measure global parameters, related to shape changes at the whole cell scale. Despite strong advances in our understanding of the molecular organization of red blood cells, the relationships between the rheology of each element of the cell composite structure, the global deformability tests, and the cell behavior in microflows are still not elucidated. This review describes recent advances in the description of the dynamics of red blood cells in shear flow and in the mechanistic understanding of this dynamics at the scale of the constitutive rheological and structural elements of the cell. These developments could open up new horizons for the determination of red blood cell mechanical parameters by analyzing their motion under low shear flows.

  12. Membrane transport of anandamide through resealed human red blood cell membranes

    DEFF Research Database (Denmark)

    Bojesen, I.N.; Hansen, Harald S.

    2005-01-01

    The use of resealed red blood cell membranes (ghosts) allows the study of the transport of a compound in a nonmetabolizing system with a biological membrane. Transmembrane movements of anandamide (N-arachidonoylethanolamine, arachidonoylethanolamide) have been studied by exchange efflux experiments...... at 0°C and pH 7.3 with albumin-free and albumin-filled human red blood cell ghosts. The efflux kinetics is biexponential and is analyzed in terms of compartment models. The distribution of anandamide on the membrane inner to outer leaflet pools is determined to be 0.275 ± 0.023, and the rate constant...... of unidirectional flux from inside to outside is 0.361 ± 0.023 s. The rate constant of unidirectional flux from the membrane to BSA in the medium ([BSA]) increases with the square root of [BSA] in accordance with the theory of an unstirred layer around ghosts. Anandamide passed through the red blood cell membrane...

  13. Optically-driven red blood cell rotor in linearly polarized laser tweezers

    Indian Academy of Sciences (India)

    Manas Khan; Samarendra K Mohanty; A K Sood

    2005-11-01

    We have constructed a dual trap optical tweezers set-up around an inverted microscope where both the traps can be independently controlled and manipulated in all the three dimensions. Here we report our observations on rotation of red blood cells (RBCs) in a linearly polarized optical trap. Red blood cells deform and become twisted in hypertonic phosphate buffer saline and when trapped, experience an unbalanced radiation pressure force. The torque generated from the unbalanced force causes the trapped RBC to rotate. Addition of Ca++ ions in the solution, keeping the osmolarity same, makes the cell membranes stiffer and the cells deform less. Thus the speed of rotation of the red blood cells can be controlled, as less deformation and in turn less asymmetry in shape produces less torque under the radiation pressure resulting in slower rotation at the same laser power.

  14. Analysis of red blood cell aggregation in cardio-pulmonary bypass (CPB) surgery.

    Science.gov (United States)

    Graaff, R; Gu, Y J; Boonstra, P W; van Oeveren, W; Rakhorst, G

    2004-06-01

    Not much is known about red cell aggregation during cardio-pulmonary bypass surgery (CPB). Blood samples from 19 patients undergoing CPB were anticoagulated with EDTA. Hematocrit was adjusted to 40%. A red blood cell aggregometer (LORCA) measured changes in light reflection from each blood sample after cessation of the rotation, and calculated an aggregation index (AI). Reflection measurements were stored. Because LORCA software failed for 87 of 171 samples, we developed new software, and applied it to the stored reflection measurements. This software failed only in 7 out of 171 cases and showed that all LORCA failures occurred for AI CPB and recovered to 37.1 +/- 13.5 at day 1. It is concluded that the new software can be used to study decreased red cell aggregation during CPB.

  15. Dynamics of red blood cells and vesicles in microchannels of oscillating width.

    Science.gov (United States)

    Braunmüller, S; Schmid, L; Franke, T

    2011-05-11

    We have studied the dynamics of red blood cells and fluid lipid vesicles in hydrodynamic flow fields created by microchannels with periodically varying channel width. For red blood cells we find a transition from a regime with oscillating tilt angle and fixed shape to a regime with oscillating shape with increasing flow velocity. We have determined the crossover to occur at a critical ratio L(y)/v(m) ≈ 2.2 × 10⁻³ s with channel width L(y) and red blood cell velocity v(m). These oscillations are superposed by shape transitions from a discocyte to a slipper shape at low velocities and a slipper to parachute transition at high flow velocities.

  16. Computer Simulation Study of Collective Phenomena in Dense Suspensions of Red Blood Cells under Shear

    CERN Document Server

    Krüger, Timm

    2012-01-01

    The rheology of dense red blood cell suspensions is investigated via computer simulations based on the lattice Boltzmann, the immersed boundary, and the finite element methods. The red blood cells are treated as extended and deformable particles immersed in the ambient fluid. In the first part of the work, the numerical model and strategies for stress evaluation are discussed. In the second part, the behavior of the suspensions in simple shear flow is studied for different volume fractions, particle deformabilities, and shear rates. Shear thinning behavior is recovered. The existence of a shear-induced transition from a tumbling to a tank-treading motion is demonstrated. The transition can be parameterized by a single quantity, namely the effective capillary number. It is the ratio of the suspension stress and the characteristic particle membrane stress. At the transition point, a strong increase in the orientational order of the red blood cells and a significant decrease of the particle diffusivity are obser...

  17. Ex-vivo expansion of red blood cells: how real for transfusion in humans?

    Science.gov (United States)

    Migliaccio, Anna Rita; Masselli, Elena; Varricchio, Lilian; Whitsett, Carolyn

    2012-03-01

    Blood transfusion is indispensable for modern medicine. In developed countries, the blood supply is adequate and safe but blood for alloimmunized patients is often unavailable. Concerns are increasing that donations may become inadequate in the future as the population ages prompting a search for alternative transfusion products. Improvements in culture conditions and proof-of-principle studies in animal models have suggested that ex-vivo expanded red cells may represent such a product. Compared to other cell therapies transfusion poses the unique challenge of requiring great cell doses (2.5×10(12) cells vs 10(7) cells). Although production of such cell numbers is theoretically possible, current technologies generate red cells in numbers sufficient only for safety studies. It is conceived that by the time these studies will be completed, technical barriers to mass cell production will have been eliminated making transfusion with ex-vivo generated red cells a reality.

  18. Numerical simulation of red blood cell suspensions behind a moving interface in a capillary

    CERN Document Server

    Zhao, Shihai

    2013-01-01

    Computational modeling and simulation are presented on the motion of red blood cells behind a moving interface in a capillary. The methodology is based on an immersed boundary method and the skeleton structure of the red blood cell (RBC) membrane is modeled as a spring network. The computational domain is moving with either a designated RBC or an interface in an infinitely long two-dimensional channel with an undisturbed flow field in front of the domain. The tanking-treading and the inclination angle of a cell in a simple shear flow are briefly discussed for the validation purpose. We then present the results of the motion of red blood cells behind a moving interface in a capillary, which show that the RBCs with higher velocity than the interface speed form a concentrated slug behind the interface.

  19. Coarse-Grained Molecular Dynamics Simulation of a Red Blood Cell

    Science.gov (United States)

    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.

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

    Directory of Open Access Journals (Sweden)

    Liu Chengqian

    2011-05-01

    Full Text Available Abstract 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.

  1. GPU-accelerated Red Blood Cells Simulations with Transport Dissipative Particle Dynamics

    CERN Document Server

    Blumers, Ansel L; Li, Zhen; Li, Xuejin; Karniadakis, George E

    2016-01-01

    Mesoscopic numerical simulations provide a unique approach for the quantification of the chemical influences on red blood cell functionalities. The transport Dissipative Particles Dynamics (tDPD) method can lead to such effective multiscale simulations due to its ability to simultaneously capture mesoscopic advection, diffusion, and reaction. In this paper, we present a GPU-accelerated red blood cell simulation package based on a tDPD adaptation of our red blood cell model, which can correctly recover the cell membrane viscosity, elasticity, bending stiffness, and cross-membrane chemical transport. The package essentially processes all computational workloads in parallel by GPU, and it incorporates multi-stream scheduling and non-blocking MPI communications to improve inter-node scalability. Our code is validated for accuracy and compared against the CPU counterpart for speed. Strong scaling and weak scaling are also presented to characterizes scalability. We observe a speedup of 10.1 on one GPU over all 16 c...

  2. Rare hereditary red blood cell enzymopathies associated with hemolytic anemia - pathophysiology, clinical aspects, and laboratory diagnosis.

    Science.gov (United States)

    Koralkova, P; van Solinge, W W; van Wijk, R

    2014-06-01

    Hereditary red blood cell enzymopathies are genetic disorders affecting genes encoding red blood cell enzymes. They cause a specific type of anemia designated hereditary nonspherocytic hemolytic anemia (HNSHA). Enzymopathies affect cellular metabolism, which, in the red cell, mainly consists of anaerobic glycolysis, the hexose monophosphate shunt, glutathione metabolism, and nucleotide metabolism. Enzymopathies are commonly associated with normocytic normochromic hemolytic anemia. In contrast to other hereditary red cell disorders such as membrane disorders or hemoglobinopathies, the morphology of the red blood cell shows no specific abnormalities. Diagnosis is based on detection of reduced specific enzyme activity and molecular characterization of the defect on the DNA level. The most common enzyme disorders are deficiencies of glucose-6-phosphate dehydrogenase (G6PD) and pyruvate kinase (PK). However, there are a number of other enzyme disorders, often much less known, causing HNSHA. These disorders are rare and often underdiagnosed, and the purpose of this review. In this brief review, we provide an overview of clinically relevant enzymes, their function in red cell metabolism, and key aspects of laboratory diagnosis.

  3. Arterio-venous flow between monochorionic twins determined during intra-uterine transfusion. Nonlinear decay of adult red blood cells

    Energy Technology Data Exchange (ETDEWEB)

    Gemert, Martin J C van; Wijngaard, Jeroen P H M van den [Laser Centre and Department of Obstetrics, Academic Medical Centre, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam (Netherlands); Pasman, Suzanne A; Vandenbussche, Frank P H A [Division of Fetal Medicine, Department of Obstetrics, Leiden University Medical Centre, Leiden (Netherlands); Lopriore, Enrico [Division of Neonatology, Department of Pediatrics, Leiden University Medical Centre, Leiden (Netherlands)], E-mail: m.j.vangemert@amc.uva.nl

    2008-07-07

    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. (letter to the editor)

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

    Directory of Open Access Journals (Sweden)

    F. Adams

    2015-01-01

    Full Text Available 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.

  5. Quantitative absorption cytometry for measuring red blood cell hemoglobin mass and volume.

    Science.gov (United States)

    Schonbrun, Ethan; Malka, Roy; Di Caprio, Giuseppe; Schaak, Diane; Higgins, John M

    2014-04-01

    We present an optical system, called the quantitative absorption cytometer (QAC), to measure the volume and hemoglobin mass of red blood cells flowing through a microfluidic channel. In contrast to clinical hematology analyzers, where cells are sphered in order for both volume and hemoglobin to be measured accurately, the QAC measures cells in their normal physiological shape. Human red blood cells are suspended in a refractive index-matching absorbing buffer, driven through a microfluidic channel, and imaged using a transmission light microscope onto a color camera. A red and a blue LED illuminate cells and images at each color are used to independently retrieve cell volume and hemoglobin mass. This system shows good agreement with red blood cell indices retrieved by a clinical hematology analyzer and in fact measures a smaller coefficient of variation of hemoglobin concentration. In addition to cell indices, the QAC returns height and mass maps of each measured cell. These quantitative images are valuable for analyzing the detailed morphology of individual cells as well as statistical outliers found in the data. We also measured red blood cells in hypertonic and hypotonic buffers to quantify the correlation between volume and hemoglobin mass under osmotic stress. Because this method is invariant to cell shape, even extremely nonspherical cells in hypertonic buffers can be measured accurately.

  6. An effect of glycoprotein IIb/IIIa inhibitors on the kinetics of red blood cells aggregation.

    Science.gov (United States)

    Sokolova, Irina A; Muravyov, Alexei V; Khokhlova, Maria D; Rikova, Sofya Yu; Lyubin, Evgeny V; Gafarova, Marina A; Skryabina, Maria N; Fedyanin, Angrey A; Kryukova, Darya V; Shahnazarov, Alexander A

    2014-01-01

    The reversible aggregation of red blood cells (RBCs) continues to be of the basic science and clinical interest. Recently it has been reported about a specific binding between fibrinogen and unknown erythrocyte glycoprotein receptors. The aim of this study was to investigate whether the red blood cell aggregation (RBCA) include the cell-cell interaction using the membrane receptors that bind such ligands as fibrinogen or fibronectin. To test this hypothesis the RBCs were incubated with monafram - the drug of the monoclonal antibodies against glycoprotein (GP) IIb/IIIa, with the GPIIb-IIIa receptor antagonist tirofiban, epifibatide and with the fibrinogen inhibiting peptide. It has been found that the RBC incubation with monafram resulted in a marked RBCA decrease mainly in persons with high level of aggregation. Another research session has shown that RBC incubation with fibronectin was accompanied by a significant RBCA rise. The monafram addition to red cell incubation medium resulted in a significant RBCA lowering. The cell incubation with tirofiban and epifibatide issued in RBCA decrease. The similar results were obtained when RBCs were incubated with the fibrinogen inhibiting peptide. Although monafram, tirofiban, eptifibatide and the fibrinogen inhibiting peptide were related to fibrinogen function they didn't inhibit RBCA completely. Therefore, under moderate and low red blood cell aggregation the cell binding is probably related to nonspecific mode. It seems evident that the specific and nonspecific modes of red blood cell aggregate formation could co-exist. Additional theoretical and experimental investigations in this area are needed.

  7. Red blood cell glutathione peroxidase activity in female nulligravid and pregnant rats

    Directory of Open Access Journals (Sweden)

    Martino Guglielmo

    2009-01-01

    Full Text Available Abstract Background The alterations of the glutathione peroxidase enzyme complex system occur in physiological conditions such as aging and oxidative stress consequent to strenuous exercise. Methods Authors optimize the spectrophotometric method to measure glutathione peroxidase activity in rat red blood cell membranes. Results The optimization, when applied to age paired rats, both nulligravid and pregnant, shows that pregnancy induces, at seventeen d of pregnancy, an increase of both reactive oxygen substance concentration in red blood cells and membrane glutathione peroxidase activity. Conclusion The glutathione peroxidase increase in erythrocyte membranes is induced by systemic oxidative stress long lasting rat pregnancy.

  8. New diffractometric equations and data processing algorithm for laser ektacytometry of red blood cells

    Science.gov (United States)

    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.

  9. Theoretical and experimental study of electroporation of red blood cells using MEMS technology

    KAUST Repository

    Deng, Peigang

    2010-01-01

    A theoretical and experimental study of electroporation (EP) of red blood cells (RBCs) was presented in this paper. With additional strain energy, an energy-based model of an electropore induced on a RBC\\'s membrane at different electric fields was proposed to predict the critical EP electric field strength. In addition, EP experiments with red blood cells at single-cell level was carried out on a micro EP chip. The measured critical EP electric field strengths are in agreement with the numerical predictions. ©2010 IEEE.

  10. Morphological and biochemical characterization of mitochondria in Torpedo red blood cells.

    Science.gov (United States)

    Pica, A; Scacco, S; Papa, F; De Nitto, E; Papa, S

    2001-02-01

    A study is presented on the morphology and respiratory functions of mitochondria from Torpedo marmorata red blood cells. In vivo staining of red blood cells and transmission electron microscopy showed the existence of a considerable number of vital and orthodox mitochondria which decreased from young erythroblasts to mature erythrocytes from 60-50 to 30-20 per cell. In erythrocytes mitochondria exhibited a canonical, functional respiratory chain. The content and activity of cytochromes in erythrocytes were, however, significantly lower as compared to mammalian tissues.

  11. Sucralose sweetener in vivo effects on blood constituents radiolabeling, red blood cell morphology and radiopharmaceutical biodistribution in rats

    Energy Technology Data Exchange (ETDEWEB)

    Rocha, G.S.; Pereira, M.O. [Universidade do Estado do Rio de Janeiro, Instituto de Biologia Roberto Alcantara Gomes, Departamento de Biofisica e Biometria, Avenida 28 de Setembro, 87, Vila Isabel, 20551030 Rio de Janeiro (Brazil); Universidade Federal do Rio Grande do Norte, Programa de Pos-Graduacao em Ciencias da Saude, Avenida General Gustavo Cordeiro de Farias, s/n, 59010180 Natal, Rio Grande do Norte (Brazil); Benarroz, M.O.; Frydman, J.N.G.; Rocha, V.C. [Universidade do Estado do Rio de Janeiro, Instituto de Biologia Roberto Alcantara Gomes, Departamento de Biofisica e Biometria, Avenida 28 de Setembro, 87, Vila Isabel, 20551030 Rio de Janeiro (Brazil); Pereira, M.J. [Universidade do Estado do Rio de Janeiro, Instituto de Biologia Roberto Alcantara Gomes, Departamento de Fisiologia, Avenida 28 de Setembro, 87, Vila Isabel, 20551030 Rio de Janeiro (Brazil); Fonseca, A.S., E-mail: adnfonseca@ig.com.b [Universidade do Estado do Rio de Janeiro, Instituto de Biologia Roberto Alcantara Gomes, Departamento de Biofisica e Biometria, Avenida 28 de Setembro, 87, Vila Isabel, 20551030 Rio de Janeiro (Brazil); Universidade Federal do Estado do Rio de Janeiro, Instituto Biomedico, Departamento de Ciencias Fisiologicas, Rua Frei Caneca, 94, Rio de Janeiro 20211040 (Brazil); Medeiros, A.C. [Universidade Federal do Rio Grande do Norte, Programa de Pos-Graduacao em Ciencias da Saude, Avenida General Gustavo Cordeiro de Farias, s/n, 59010180 Natal, Rio Grande do Norte (Brazil); Bernardo-Filho, M. [Universidade do Estado do Rio de Janeiro, Instituto de Biologia Roberto Alcantara Gomes, Departamento de Biofisica e Biometria, Avenida 28 de Setembro, 87, Vila Isabel, 20551030 Rio de Janeiro (Brazil); Instituto Nacional do Cancer, Coordenadoria de Pesquisa Basica, Praca Cruz Vermelha, 23, 20230130 Rio de Janeiro (Brazil)

    2011-01-15

    Effects of sucralose sweetener on blood constituents labelled with technetium-99m ({sup 99m}Tc) on red blood cell (RBC) morphology, sodium pertechnetate (Na{sup 99m}TcO{sub 4}) and diethylenetriaminepentaacetic acid labeled with {sup 99m}Tc ({sup 99m}Tc-DTPA) biodistribution in rats were evaluated. Radiolabeling on blood constituents from Wistar rats was undertaken for determining the activity percentage (%ATI) on blood constituents. RBC morphology was also evaluated. Na{sup 99m}TcO{sub 4} and {sup 99m}Tc-DTPA biodistribution was used to determine %ATI/g in organs. There was no alteration on RBC blood constituents and morphology %ATI. Sucralose sweetener was capable of altering %ATI/g of the radiopharmaceuticals in different organs. These findings are associated to the sucralose sweetener in specific organs.

  12. Effect of red wine and red grape extract on blood lipids, haemostatic factors, and other risk factors for cardiovascular disease

    DEFF Research Database (Denmark)

    Hansen, Alice Schmidt; Marckmann, P.; Dragsted, L.O.

    2005-01-01

    . Plasma high-density lipoprotein (HDL)- cholesterol (HDL-C), low-density lipoprotein (LDL)-cholesterol (LDL-C), HDL-C/LDL-C-ratio, very-low-density lipoprotein ( VLDL)- triacylglycerol, total cholesterol, fibrinogen, factor VII coagulant activity (FVIIc), blood pressure, and body weight were determined......: 300 ml/day, 38.3 g alcohol/day, female subjects: 200 ml/ day, 25.5 g alcohol/day), 2: water+red grape extract tablets ( wine-equivalent dose), 3: water+red grape extract tablets ( half dose), or 4: water+placebo tablets for a period of 4 weeks. No other sources of alcohol or anthocyanin were allowed...... before and after intervention. Results: Wine consumption was associated with a significant 11 - 16% increase in fasting HDL-C and 8 - 15% decrease in fasting fibrinogen relative to not drinking wine. There were no significant treatment effects on fasting LDL-C, HDL-C/LDL-C-ratio, VLDL...

  13. Biomechanics and biorheology of red blood cells in sickle cell anemia

    Science.gov (United States)

    Li, Xuejin; Dao, Ming; Lykotrafitis, George; Karniadakis, George Em

    2017-01-01

    Sickle cell anemia (SCA) is an inherited blood disorder that causes painful crises due to vaso-occlusion of small blood vessels. The primary cause of the clinical phenotype of SCA is the intracellular polymerization of sickle hemoglobin resulting in sickling of red blood cells (RBCs) in deoxygenated conditions. In this review, we discuss the biomechanical and biorheological characteristics of sickle RBCs and sickle blood as well as their implications toward a better understanding of the pathophysiology and pathogenesis of SCA. Additionally, we highlight the adhesive heterogeneity of RBCs in SCA and their specific contribution to vaso-occlusive crisis. PMID:27876368

  14. Biomechanics and biorheology of red blood cells in sickle cell anemia.

    Science.gov (United States)

    Li, Xuejin; Dao, Ming; Lykotrafitis, George; Karniadakis, George Em

    2017-01-04

    Sickle cell anemia (SCA) is an inherited blood disorder that causes painful crises due to vaso-occlusion of small blood vessels. The primary cause of the clinical phenotype of SCA is the intracellular polymerization of sickle hemoglobin resulting in sickling of red blood cells (RBCs) in deoxygenated conditions. In this review, we discuss the biomechanical and biorheological characteristics of sickle RBCs and sickle blood as well as their implications toward a better understanding of the pathophysiology and pathogenesis of SCA. Additionally, we highlight the adhesive heterogeneity of RBCs in SCA and their specific contribution to vaso-occlusive crisis.

  15. Hyperkalemia after irradiation of packed red blood cells: Possible effects with intravascular fetal transfusion

    Energy Technology Data Exchange (ETDEWEB)

    Thorp, J.A.; Plapp, F.V.; Cohen, G.R.; Yeast, J.D.; O' Kell, R.T.; Stephenson, S. (St. Luke' s Perinatal Center, Kansas City, MO (USA))

    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.

  16. Red blood cells and thrombin generation in sickle cell disease.

    Science.gov (United States)

    Whelihan, Matthew F; Lim, Ming Y; Key, Nigel S

    2014-05-01

    The prothrombotic nature of sickle cell disease (SCD) is evidenced by the chronically elevated levels of almost all coagulation activation biomarkers, and an increased incidence of certain thrombotic events, including venous thromboembolism. Numerous studies have attempted to define the extent and elucidate the mechanism of the observed increase in thrombin generation in SCD patients in vivo. In general, these studies were performed using thrombin generation assays in platelet poor or platelet rich plasma and showed little difference in endogenous thrombin potential between the SCD cohort and healthy matched controls. In SCD, erythrocytes and monocytes have been demonstrated to exhibit procoagulant characteristics. Thus, the absence of these cellular components in standard thrombin generation assays may fail to reflect global hypercoagulability in the whole blood of patients with SCD. We were therefore surprised to see no difference in net thrombin generation in tissue factor-initiated initiated clotting of whole blood from patients with SCD. However, we are continuing to reconcile these seemingly disparate observations by slight modifications of the whole blood model that include alternative coagulation triggers and a re-examination of the net thrombin generation when the protein/protein S system is simultaneously interrogated.

  17. Deformability of Red Blood Cells and Correlation with ATP Content during Storage as Leukocyte-Depleted Whole Blood.

    Science.gov (United States)

    Karger, Ralf; Lukow, Christian; Kretschmer, Volker

    2012-08-01

    BACKGROUND: Storage duration of red cells has been associated with increased morbidity and mortality following transfusion. This association has been attributed to the loss of deformability of stored red cells leading to deterioration of microvascular perfusion. ATP content is considered a critical determinant of the deformability of stored red cells. METHODS: ATP content and deformability were determined after storage for up to 49 days in 40 leukocyte-depleted whole blood units. Red cell deformability was determined using a laser-assisted optical rotational cell analyzer (LORCA( (®) )) employing shear stress (SS) ranging from 0.3 to 30 Pa. Deformability was expressed as the elongation index (EI). EI was correlated with ATP content. RESULTS: ATP content decreased from 3.5 to 1.7 ?mol/g hemoglobin. EI increased from 0.03 to 0.05 at an SS of 0.3 Pa, and decreased from 0.62 to 0.59 at an SS of 30 Pa. Correlation coefficient (r) of ATP vs. EI at 0.3 Pa ranged from -0.17 to +0.15 during storage. At 30 Pa, r ranged from -0.03 to +0.45. Correlation increased with storage irrespective of SS, and increased with SS irrespective of storage. CONCLUSIONS: ATP content is not a valid surrogate marker for red cell deformability and may not reflect in vivo survival of stored red cells.

  18. Serum immunoreactive erythropoietin and red blood cell mass during pregnancy in conscious rats.

    Science.gov (United States)

    Del Valle, G O; Mosher, M D; Conrad, K P

    1993-08-01

    Serum erythropoietin concentration increases during human pregnancy and presumably accounts for expansion of red blood cell mass. The mechanism(s) underlying gestational changes of serum erythropoietin are unknown. Moreover, if erythropoietin synthesis increases, then the organ(s) questions about erythropoietin in pregnancy, we first set out to establish an animal model. Chronically instrumented, conscious unrestrained rats were studied. 51Cr-labeled red blood cells and radioimmunoassay were used to assess red blood cell mass and serum erythropoietin, respectively. Except for a lower hematocrit (P pregnancy rats were comparable to those measured in virgin control animals. Significant increases in total blood volume, plasma volume, and red blood cell mass were observed by gestational day 13 (midpregnancy) when compared with virgin control rats. These changes were even more pronounced on gestational day 20. Serum immunoreactive erythropoietin was also significantly increased at both of these stages of pregnancy. We conclude that the gravid rat is a reliable animal model of human gestation in which to further investigate erythropoietin in pregnancy.

  19. Effects of He-Ne laser irradiation on red blood cells in vitro

    Science.gov (United States)

    Ghadage, Vijay H.; Kulkarni, Gauri R.

    2011-03-01

    Laser radiation has many applications in biomedical field, such as wound healing, tissue repairing, heating and ablation processes. Intravenous low power laser radiation is used clinically for skin and vascular disorders. Laser radiation improves microcirculation and modulates the rheological properties of blood. FTIR (Fourier Transform Infra Red Spectra) is used to see the structural changes in erythrocyte membrane. In the present work He Ne laser (λ= 632nm, power=2mW) is used to irradiate human Red blood cells. Red blood cells are separated from human whole blood using centrifugation method (time=10 min., temperature=15°C and RPM=3000) and then exposed to HeNe laser radiation. Laser exposure time is varied from 10 min. to 40min for Red blood cells. Absorption spectrum, FTIR and fluorescence spectra of RBC are compared before and after HeNe laser irradiation. The absorption spectrum of RBC after exposure to HeNe laser shows a significant decrease in absorbance. The FTIR spectrum of non irradiated RBC clearly show the peaks due to O-H (free group), C=O (amide I group), N=O (nitro group), C-O (anhydride group) and C-H (aromatic group). Laser radiation changes in transmittance in FTIR spectra related to C=O group and percentage of transmittance increases for O-H, C=C, N=O, C-O and C-H group.

  20. Reflectance confocal microscopy of red blood cells: simulation and experiment (Conference Presentation)

    Science.gov (United States)

    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.

  1. Direct detection of red blood cell fragments: a new flow cytometric method to evaluate hemolysis in blood pumps.

    Science.gov (United States)

    Linneweber, J; Chow, T W; Takano, T; Maeda, T; Nonaka, K; Schulte-Eistrup, S; Kawahito, S; Elert, O; Moake, J L; Nosé, Y

    2001-01-01

    Pump induced hemolysis is presently evaluated by measuring plasma free hemoglobin (fHb). However, this method has disadvantages because quantification of fHb depends on hematocrit (HCT) and hemoglobin (Hb) levels. The aim of this work was to devise a hemoglobin independent method, capable of quantifying cell trauma directly by measuring the number of red blood cell (RBC) fragments. Whole blood flow cytometry was used to quantify circulating RBC fragments derived from a roller pump (Sarns, Inc. Model 2 M 6,002) and a centrifugal pump (Gyro C1E3, Kyocera Corp.). The pumps were tested in a mock circuit for 2 hr (5 L/min flow against 100 mm Hg pressure head). Red blood cell fragments were quantified by a phycoerythrin (PE) labeled glycophorin A antibody specific for erythrocytes. Red blood cell fragments were smaller than the intact RBC population and overlapped in size with the platelet population (based on forward- and side-light scattering measurements). For the roller pump, the values for RBC fragments increased from 1,090 +/- 260/microl at 0 min to 14,880 +/- 5,900/microl after 120 min. In contrast, using the centrifugal pump, there was little increase in RBC fragments (from 730 +/- 270/microl at 0 min to 1,400 +/- 840/microl after 120 min). Flow cytometry can be used for the rapid, sensitive, hemoglobin independent evaluation of pump induced RBC trauma.

  2. Morphological analysis of red blood cells by polychromatic interference microscopy of thin films

    Science.gov (United States)

    Dyachenko, A. A.; Malinova, L. I.; Ryabukho, V. P.

    2016-11-01

    Red blood cells (RBC) distribution width (RDW) is a promising hematological parameter with broadapplications in clinical practice; in various studies RDWhas been shown to be associated with increased risk of heart failure (HF) in general population. It predicts mortality and other major adverse events in HF patients. In this report new method of RDWmeasurement is presented. It's based on interference color analysis of red blood cells in blood smear and further measurement of its optical thickness. Descriptive statistics of the of the RBC optical thickness distribution in a blood smear were used for RDW estimation in every studied sample. Proposed method is considered to be avoiding type II errors and minimizing the variability of measured RDW.

  3. Red blood cell antioxidant enzymes in age-related macular degeneration.

    OpenAIRE

    De La Paz, M A; Zhang, J; Fridovich, I

    1996-01-01

    AIMS/BACKGROUND: Oxidative damage has been proposed to be involved in the pathogenesis of age-related macular degeneration (ARMD). The purpose of this study was to evaluate whether red blood cell antioxidant enzyme activity correlates with severity of aging maculopathy in affected individuals. METHODS: Blood samples were obtained from 54 patients with varying severity of aging maculopathy and 12 similarly aged individuals with normal ophthalmoscopic examination. Macular findings were graded a...

  4. Alga-lysing bioreactor and the dominant bacteria strain

    Institute of Scientific and Technical Information of China (English)

    PEI Hai-yan; HU Wen-rong; MU Rui-min; LI Xiao-cai

    2007-01-01

    Alga-lysing bacteria have been paid much attention to in recent years. In this study, the alga-lysing strain P05 which was isolated from an immobilizing biosystem was immobilized by coke and elastic filler, forming two biological reactors. The removal efficiencies of algae, NH3-N and organic matter using the two reactors were studied. The results showed that strain P05 was an ideal algal-lysing bacteria strain because it was easy to be immobilized by coke and elastic filler which are of cheap, low biodegradability and the simple immobilization procedure. After 7 d filming, the biological film could be formed and the reactors were used to treat the eutrophic water. These two reactors were of stability and high effect with low cost and easy operation. The optimal hydraulic retention time (HRT) of each reactor was 4 h. The algae removal rates were 80.38% and 82.1% (in term of Chl-a) of coke reactor and filler reactor, respectively. And that of NH3-N were 52.3% and 52.7%. The removal rates of CODMn were 39.03% and 39.64%. The strain P05 was identified as Bacillus sp. by PCR amplification of the 16S rRNA gene, BLAST analysis, and comparison with sequences in the GenBank nucleotide database.

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

    Science.gov (United States)

    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.

  6. Enzymes and membrane proteins of ADSOL-preserved red blood cells

    Directory of Open Access Journals (Sweden)

    Maria Sueli Soares Leonart

    2000-03-01

    Full Text Available CONTEXT: The preservative solution ADSOL (adenine, dextrose, sorbitol, sodium chloride and mannitol maintains red cell viability for blood trans-fusion for 6 weeks. It would be useful to know about its preservation qualities over longer periods. OBJECTIVE: To determine some red cell biochemical parameters for peri-ods of up to 14 weeks in order to determine whether the red cell metabo-lism integrity would justify further studies aiming at increasing red cell preservation and viability. DESIGN: Biochemical evaluation designed to study red cell preservation. SETTING: São Paulo University erythrocyte metabolism referral center. SAMPLE: Six normal blood donors from the University Hospital of the Universidade Federal do Paraná, Curitiba, Brazil. MAIN MEASUREMENTS: Weekly assay of erythrocyte adenosine-5´-triphosphate (ATP, 2,3-diphosphoglycerate (2,3DPG, hexokinase (HX, phosphofructokinase (PFK, pyruvate kinase (PK, glucose-6-phosphate dehydrogenase (G-6-PD, 6-phosphogluconic dehydrogenase (6-PGD, glyceraldehyde-3-phosphate dehydrogenase (GAPD, glutathione reduc-tase (GR, glutathione peroxidase (GSHPx, plasma sodium and potas-sium, blood pH, and membrane proteins of red cells preserved in ADSOL were studied during storage for 14 weeks storage. RESULTS: During ADSOL preservation, erythrocyte ATP concentration decreased 60% after 5 weeks, and 90% after 10 weeks; the pH fell from 6.8 to 6.4 by the 14th week. 2,3-DPG concentration was stable during the first week, but fell 90% after 3 weeks and was exhausted after 5 weeks. By the end of the 5th week, an activity decrease of 16-30% for Hx, GAPD, GR, G-6-PD and 6-PGD, 35% for PFK and GSHPx, and 45% for PK were observed. Thereafter, a uniform 10% decay was observed for all enzymes up to the 14th week. The red blood cell membrane pro-teins did not show significant alterations in polyacrylamide gel electro-phoresis (SDS-PAGE during the 14 weeks. CONCLUSION: Although the blood viability was shown to be poor

  7. Carbonic anhydrase activity in the red blood cells of sea level and high altitude natives.

    Science.gov (United States)

    Gamboa, J; Caceda, R; Gamboa, A; Monge-C, C

    2000-01-01

    Red blood cell carbonic anhydrase (CA) activity has not been studied in high altitude natives. Because CA is an intraerythocytic enzyme and high altitude natives are polycythemic, it is important to know if the activity of CA per red cell volume is different from that of their sea level counterparts. Blood was collected from healthy subjects living in Lima (150m) and from twelve subjects from Cerro de Pasco (4330m), and hematocrit and carbonic anhydrase activity were measured. As expected, the high altitude natives had significantly higher hematocrits than the sea level controls (p = 0.0002). No difference in the CA activity per milliliter of red cells was found between the two populations. There was no correlation between the hematocrit and CA activity.

  8. Mechanics of extracellular vesicles derived from malaria parasiteinfected Red Blood Cells

    NARCIS (Netherlands)

    Sorkin, Raya; Vorselen, Daan; Ofir-Birin, Yifat; Roos, Wouter H.; MacKintosh, Fred C.; Regev-Rudzki, Neta; Wuite, Gijs J. L.

    2016-01-01

    Malaria is a life-threatening disease caused by parasites that are transmitted through the bites of infected mosquitoes, with Plasmodium falciparum (Pf) causing the most severe form of malaria (1). Very recently it was discovered that Pf infected red blood cells (iRBC) directly transfer information

  9. Exome Genotyping Identifies Pleiotropic Variants Associated with Red Blood Cell Traits

    DEFF Research Database (Denmark)

    Chami, Nathalie; Chen, Ming-Huei; Slater, Andrew J

    2016-01-01

    Red blood cell (RBC) traits are important heritable clinical biomarkers and modifiers of disease severity. To identify coding genetic variants associated with these traits, we conducted meta-analyses of seven RBC phenotypes in 130,273 multi-ethnic individuals from studies genotyped on an exome ar...

  10. Normal Reference Value of Red Blood Cell Count of Chinese Presenile Men and Geographical Factors

    Institute of Scientific and Technical Information of China (English)

    HE Jinwei; GE Miao; SU Huimin; LIANG Wei; CHEN Hongfei

    2007-01-01

    This paper aims at providing a scientific basis for unifying the normal reference value standards of red blood cell count of Chinese presenile men. The paper, using microscopical counting method, studies the relationship between the normal reference values of 38,061 samples of red blood cell count ofpresenile men and eight geographical factors in297 units in China. It is found that the correlation of geographical factors and the normal reference value of red blood cell count of presenile men is quite significant (F=303.00, P=0.000). By using the method of stepwise regression analysis,one regression equation is inferred. It is concluded that if geographical data are obtained in a certain area, the normal reference value of red blood cell count of presenile men in this area can be reckoned by using the regression analysis.Furthermore, according to the geographical factors, China can be divided into eight regions: Northeast China Region,North China Region, Shanxi-Shaanxi-Inner Mongolia Region, Middle and Lower Reaches of the Changjiang River Region, Southeast China Region, Northwest China Region, Southwest China Region and Qinghai-Tibet Plateau Region.

  11. Incidental detection of a bleeding gastrointestinal stromal tumor on Tc-99m red blood cell scintigraphy.

    Science.gov (United States)

    Santhosh, Sampath; Bhattacharya, Anish; Gupta, Vikas; Singh, Rajinder; Radotra, Bishan Dass; Mittal, Bhagwant Rai

    2012-10-01

    The role of 99m-technetium labeled red blood cell (RBC) scintigraphy in acute gastro-intestinal bleed is well-established. The authors report a case of a bleeding gastrointestinal stromal tumor (GIST) incidentally discovered on Tc-99m RBC scintigraphy.

  12. Seventy-five genetic loci influencing the human red blood cell

    NARCIS (Netherlands)

    van der Harst, Pim; Zhang, Weihua; Mateo Leach, Irene; Rendon, Augusto; Verweij, Niek; Sehmi, Joban; Paul, Dirk S; Elling, Ulrich; Allayee, Hooman; Li, Xinzhong; Radhakrishnan, Aparna; Tan, Sian-Tsung; Voss, Katrin; Weichenberger, Christian X; Albers, Cornelis A; Al-Hussani, Abtehale; Asselbergs, Folkert W; Ciullo, Marina; Danjou, Fabrice; Dina, Christian; Esko, Tõnu; Evans, David M; Franke, Lude; Gögele, Martin; Hartiala, Jaana; Hersch, Micha; Holm, Hilma; Hottenga, Jouke-Jan; Kanoni, Stavroula; Kleber, Marcus E; Lagou, Vasiliki; Langenberg, Claudia; Lopez, Lorna M; Lyytikäinen, Leo-Pekka; Melander, Olle; Murgia, Federico; Nolte, Ilja M; O'Reilly, Paul F; Padmanabhan, Sandosh; Parsa, Afshin; Pirastu, Nicola; Porcu, Eleonora; Portas, Laura; Prokopenko, Inga; Ried, Janina S; Shin, So-Youn; Tang, Clara S; Teumer, Alexander; Traglia, Michela; Ulivi, Sheila; Westra, Harm-Jan; Yang, Jian; Zhao, Jing Hua; Anni, Franco; Abdellaoui, Abdel; Attwood, Antony; Balkau, Beverley; Bandinelli, Stefania; Bastardot, François; Benyamin, Beben; Boehm, Bernhard O; Cookson, William O; Das, Debashish; de Bakker, Paul I W; de Boer, Rudolf A; de Geus, Eco J C; de Moor, Marleen H; Dimitriou, Maria; Domingues, Francisco S; Döring, Angela; Engström, Gunnar; Eyjolfsson, Gudmundur Ingi; Ferrucci, Luigi; Fischer, Krista; Galanello, Renzo; Garner, Stephen F; Genser, Bernd; Gibson, Quince D; Girotto, Giorgia; Gudbjartsson, Daniel Fannar; Harris, Sarah E; Hartikainen, Anna-Liisa; Hastie, Claire E; Hedblad, Bo; Illig, Thomas; Jolley, Jennifer; Kähönen, Mika; Kema, Ido P; Kemp, John P; Liang, Liming; Lloyd-Jones, Heather; Loos, Ruth J F; Meacham, Stuart; Medland, Sarah E; Meisinger, Christa; Memari, Yasin; Mihailov, Evelin; Miller, Kathy; Moffatt, Miriam F; Nauck, Matthias; Novatchkova, Maria; Nutile, Teresa; Olafsson, Isleifur; Onundarson, Pall T; Parracciani, Debora; Penninx, Brenda W; Perseu, Lucia; Piga, Antonio; Pistis, Giorgio; Pouta, Anneli; Puc, Ursula; Raitakari, Olli; Ring, Susan M; Robino, Antonietta; Ruggiero, Daniela; Ruokonen, Aimo; Saint-Pierre, Aude; Sala, Cinzia; Salumets, Andres; Sambrook, Jennifer; Schepers, Hein; Schmidt, Carsten Oliver; Silljé, Herman H W; Sladek, Rob; Smit, Johannes H; Starr, John M; Stephens, Jonathan; Sulem, Patrick; Tanaka, Toshiko; Thorsteinsdottir, Unnur; Tragante, Vinicius; van Gilst, Wiek H; van Pelt, L Joost; van Veldhuisen, Dirk J; Völker, Uwe; Whitfield, John B; Willemsen, Gonneke; Winkelmann, Bernhard R; Wirnsberger, Gerald; Algra, Ale; Cucca, Francesco; d'Adamo, Adamo Pio; Danesh, John; Deary, Ian J; Dominiczak, Anna F; Elliott, Paul; Fortina, Paolo; Froguel, Philippe; Gasparini, Paolo; Greinacher, Andreas; Hazen, Stanley L; Jarvelin, Marjo-Riitta; Khaw, Kay Tee; Lehtimäki, Terho; Maerz, Winfried; Martin, Nicholas G; Metspalu, Andres; Mitchell, Braxton D; Montgomery, Grant W; Moore, Carmel; Navis, Gerjan; Pirastu, Mario; Pramstaller, Peter P; Ramirez-Solis, Ramiro; Schadt, Eric; Scott, James; Shuldiner, Alan R; Smith, George Davey; Smith, J Gustav; Snieder, Harold; Sorice, Rossella; Spector, Tim D; Stefansson, Kari; Stumvoll, Michael; Tang, W H Wilson; Toniolo, Daniela; Tönjes, Anke; Visscher, Peter M; Vollenweider, Peter; Wareham, Nicholas J; Wolffenbuttel, Bruce H R; Boomsma, Dorret I; Beckmann, Jacques S; Dedoussis, George V; Deloukas, Panos; Ferreira, Manuel A; Sanna, Serena; Uda, Manuela; Hicks, Andrew A; Penninger, Josef Martin; Gieger, Christian; Kooner, Jaspal S; Ouwehand, Willem H; Soranzo, Nicole; Chambers, John C

    2012-01-01

    Anaemia is a chief determinant of global ill health, contributing to cognitive impairment, growth retardation and impaired physical capacity. To understand further the genetic factors influencing red blood cells, we carried out a genome-wide association study of haemoglobin concentration and related

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

    Science.gov (United States)

    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.

  14. Electrical properties of the red blood cell membrane and immunohematological investigation

    Directory of Open Access Journals (Sweden)

    Heloise Pöckel Fernandes

    2011-01-01

    Full Text Available Hemagglutination is widely used in transfusion medicine and depends on several factors including antigens, antibodies, electrical properties of red blood cells and the environment of the reaction. Intermolecular forces are involved in agglutination with cell clumping occurring when the aggregation force is greater than the force of repulsion. Repulsive force is generated by negative charges on the red blood cell surface that occur due to the presence of the carboxyl group of sialic acids in the cell membrane; these charges create a repulsive electric zeta potential between cells. In transfusion services, specific solutions are used to improve hemagglutination, including enzymes that reduce the negative charge of red blood cells, LISS which improves the binding of antibodies to antigens and macromolecules that decrease the distance between erythrocytes. The specificity and sensitivity of immunohematological reactions depend directly on the appropriate use of these solutions. Knowledge of the electrical properties of red blood cells and of the action of enhancement solutions can contribute to the immunohematology practice in transfusion services.

  15. Detection of QTL for immune response to Sheep Red Blood Cells in laying hens

    NARCIS (Netherlands)

    Siwek-Gapinska, M.Z.; Cornelissen, S.J.B.; Nieuwland, M.G.B.; Buitenhuis, A.J.; Bovenhuis, H.; Crooijmans, R.P.M.A.; Groenen, M.A.M.; Vries Reilingh, de G.; Parmentier, H.K.; Poel, van der J.J.

    2003-01-01

    The aim of this study is to detect quantitative trait loci (QTL) involved in the regulation of the primary and the secondary immune response to sheep red blood cells (SRBC) in a resource population using microsatellite DNA markers. The F2 resource population originates from a cross of two divergentl

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

    Science.gov (United States)

    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.

  17. Dual effects of Ginkgo biloba leaf extract on human red blood cells.

    Science.gov (United States)

    He, Jing; Lin, Juan; Li, Jing; Zhang, Jian-Hong; Sun, Xue-Min; Zeng, Cheng-Ming

    2009-02-01

    Extracts from the leaves of Ginkgo biloba have been used in Chinese medicine for thousands of years. Today, various standardized preparations from G. biloba leaf extract have been developed. G. biloba leaf extract, which contains flavonoids and terpenoids as the major biologically active components, has become one of the most popular and commonly used herbal remedies due to its wide spectrum of beneficial effects on health. In this study, we investigated the effects of G. biloba leaf extract on the properties of human red blood cells in the presence and absence of amyloid peptide (Abeta25-35), peroxide and hypotonic stress. The results suggest that G. biloba leaf extract has a dual action, both protective and disruptive, on red blood cells, depending on whether an exogenous stress is present. G. biloba leaf extract has a protective role on red blood cells against Abeta- and hypotonic pressure-induced haemolysis, peroxide-induced lipoperoxidation, as well as glutathione consumption and methaemoglobin formation. On the other hand, G. biloba leaf extract also exhibited damage to red blood cells by increasing cell fragility, changing cellular morphology and inducing glutathione consumption and methaemoglobin formation, especially when applied at high doses. These anti- and pro-oxidative activities of polyphenolic substances are thought to be involved in the dual function of G. biloba leaf extract. The results of this study suggest that high doses of herbal remedies and dietary supplements can be toxic to cells.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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 ...

  20. How should the optical tweezers experiment be used to characterize the red blood cell membrane mechanics?

    Science.gov (United States)

    Sigüenza, Julien; Mendez, Simon; Nicoud, Franck

    2017-05-03

    Stretching red blood cells using optical tweezers is a way to characterize the mechanical properties of their membrane by measuring the size of the cell in the direction of the stretching (axial diameter) and perpendicularly (transverse diameter). Recently, such data have been used in numerous publications to validate solvers dedicated to the computation of red blood cell dynamics under flow. In the present study, different mechanical models are used to simulate the stretching of red blood cells by optical tweezers. Results first show that the mechanical moduli of the membranes have to be adjusted as a function of the model used. In addition, by assessing the area dilation of the cells, the axial and transverse diameters measured in optical tweezers experiments are found to be insufficient to discriminate between models relevant to red blood cells or not. At last, it is shown that other quantities such as the height or the profile of the cell should be preferred for validation purposes since they are more sensitive to the membrane model.

  1. DETERMINANTS OF RED-BLOOD-CELL DEFORMABILITY IN RELATION TO CELL AGE

    NARCIS (Netherlands)

    BOSCH, FH; WERRE, JM; ROERDINKHOLDERSTOELWINDER, B; HULS, T; WILLEKENS, FLA; WICHERS, G; HALIE, MR

    1994-01-01

    Red blood cell (RBC) deformability was determined with an ektacytometer in fractions separated on the basis of differences in cell volume or density. Deformability was measured with ektacytometry (rpm-scan and osmo-scan). We studied three groups of RBC fractions:l. By counterflow centrifugation we o

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

    Science.gov (United States)

    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.

  3. Global Attractivity of Positive Periodic Solutions for a Survival Model of Red Blood Cells

    Institute of Scientific and Technical Information of China (English)

    Xin-min Wu; Jing-wen Li

    2007-01-01

    In this paper, we deal with a model for the survival of red blood cells with periodic coefficients x′(t)=- μ(t)x(t)+P(t)e-γ(t)x(t-(τ))>0. (*)A new sufficient condition for global attractivity of positive periodic solutions of Eq.(*) is obtained. Our criterion improves corresponding result obtained by Li and Wang in 2005.

  4. Exome Genotyping Identifies Pleiotropic Variants Associated with Red Blood Cell Traits

    NARCIS (Netherlands)

    Chami, N. (Nathalie); M.-H. Chen (Ming-Huei); Slater, A.J. (Andrew J.); Eicher, J.D. (John D.); E. Evangelou (Evangelos); Tajuddin, S.M. (Salman M.); Love-Gregory, L. (Latisha); T. Kacprowski (Tim); U.M. Schick (Ursula); Nomura, A. (Akihiro); Giri, A. (Ayush); Lessard, S. (Samuel); J. Brody (Jennifer); C. Schurmann (Claudia); V.S. Pankratz (Shane); L.R. Yanek (Lisa); A. Manichaikul (Ani); R. Pazoki (Raha); E. Mihailov (Evelin); W.D. Hill (W. David); Raffield, L.M. (Laura M.); A.D. Burt (Alastair); T.M. Bartz (Traci M.); D.M. Becker (Diane); L.C. Becker (Lewis); E.A. Boerwinkle (Eric); J. Bork-Jensen (Jette); E.P. Bottinger (Erwin); M.L. O'Donoghue (Michelle L.); D.R. Crosslin (David); de Denus, S. (Simon); Dubé, M.-P. (Marie-Pierre); P. Elliott (Paul); G. Engström; M. Evans (Michele); J. Floyd (James); M. Fornage (Myriam); Gao, H. (He); A. Greinacher (Andreas); V. Gudnason (Vilmundur); T. Hansen (T.); T.B. Harris (Tamara); C. Hayward (Caroline); Hernesniemi, J. (Jussi); H. Highland (Heather); J.N. Hirschhorn (Joel); Hofman, A. (Albert); Irvin, M.R. (Marguerite R.); M. Kähönen (Mika); E.M. Lange (Ethan); Launer, L.J. (Lenore J.); T. Lehtimäki (Terho); Li, J. (Jin); D.C. Liewald (David C.); A. Linneberg (Allan); Y. Liu (Yongmei); Y. Lu (Yingchang); L.-P. Lyytikäinen (Leo-Pekka); R. Mägi (Reedik); J. Mathias (Jasmine); O. Melander (Olle); A. Metspalu (Andres); K. Mononen (Kari); M.A. Nalls (Michael); D.A. Nickerson (Deborah); K. Nikus (Kjell); C.J. O'Donnell (Christopher); M. Orho-Melander (Marju); O. Pedersen (Oluf); A. Petersmann (Astrid); Polfus, L. (Linda); B.M. Psaty (Bruce); O.T. Raitakari (Olli T.); Raitoharju, E. (Emma); Richard, M. (Melissa); K.M. Rice (Kenneth); F. Rivadeneira Ramirez (Fernando); Rotter, J.I. (Jerome I.); Schmidt, F. (Frank); A.V. Smith (Albert Vernon); J.M. Starr (John); K.D. Taylor (Kent); A. Teumer (Alexander); Thuesen, B.H. (Betina H.); Torstenson, E.S. (Eric S.); R.P. Tracy (Russell); I. Tzoulaki; N.A. Zakai (Neil); Vacchi-Suzzi, C. (Caterina); C.M. van Duijn (Cock); F.J.A. van Rooij (Frank); M. Cushman (Mary Ann); I.J. Deary (Ian J.); Velez Edwards, D.R. (Digna R.); Vergnaud, A.-C. (Anne-Claire); L.C. Wallentin (Lars); D. Waterworth (Dawn); White, H.D. (Harvey D.); J.F. Wilson (James); A.B. Zonderman; S. Kathiresan (Sekar); N. Grarup (Niels); T. Esko (Tõnu); R.J.F. Loos (Ruth); L.A. Lange (Leslie); Faraday, N. (Nauder); Abumrad, N.A. (Nada A.); T.L. Edwards (Todd L.); S.K. Ganesh (Santhi); P. Auer (Paul); A.D. Johnson (Andrew); A. Reiner (Alexander); G. Lettre (Guillaume)

    2016-01-01

    textabstractRed blood cell (RBC) traits are important heritable clinical biomarkers and modifiers of disease severity. To identify coding genetic variants associated with these traits, we conducted meta-analyses of seven RBC phenotypes in 130,273 multi-ethnic individuals from studies genotyped on an

  5. Seventy-five genetic loci influencing the human red blood cell

    NARCIS (Netherlands)

    van der Harst, Pim; Zhang, Weihua; Mateo Leach, Irene; Rendon, Augusto; Verweij, Niek; Sehmi, Joban; Paul, Dirk S; Elling, Ulrich; Allayee, Hooman; Li, Xinzhong; Radhakrishnan, Aparna; Tan, Sian-Tsung; Voss, Katrin; Weichenberger, Christian X; Albers, Cornelis A; Al-Hussani, Abtehale; Asselbergs, Folkert W; Ciullo, Marina; Danjou, Fabrice; Dina, Christian; Esko, Tõnu; Evans, David M; Franke, Lude; Gögele, Martin; Hartiala, Jaana; Hersch, Micha; Holm, Hilma; Hottenga, Jouke-Jan; Kanoni, Stavroula; Kleber, Marcus E; Lagou, Vasiliki; Langenberg, Claudia; Lopez, Lorna M; Lyytikäinen, Leo-Pekka; Melander, Olle; Murgia, Federico; Nolte, Ilja M; O'Reilly, Paul F; Padmanabhan, Sandosh; Parsa, Afshin; Pirastu, Nicola; Porcu, Eleonora; Portas, Laura; Prokopenko, Inga; Ried, Janina S; Shin, So-Youn; Tang, Clara S; Teumer, Alexander; Traglia, Michela; Ulivi, Sheila; Westra, Harm-Jan; Yang, Jian; Zhao, Jing Hua; Anni, Franco; Abdellaoui, Abdel; Attwood, Antony; Balkau, Beverley; Bandinelli, Stefania; Bastardot, François; Benyamin, Beben; Boehm, Bernhard O; Cookson, William O; Das, Debashish; de Bakker, Paul I W; de Boer, Rudolf A; de Geus, Eco J C; de Moor, Marleen H; Dimitriou, Maria; Domingues, Francisco S; Döring, Angela; Engström, Gunnar; Eyjolfsson, Gudmundur Ingi; Ferrucci, Luigi; Fischer, Krista; Galanello, Renzo; Garner, Stephen F; Genser, Bernd; Gibson, Quince D; Girotto, Giorgia; Gudbjartsson, Daniel Fannar; Harris, Sarah E; Hartikainen, Anna-Liisa; Hastie, Claire E; Hedblad, Bo; Illig, Thomas; Jolley, Jennifer; Kähönen, Mika; Kema, Ido P; Kemp, John P; Liang, Liming; Lloyd-Jones, Heather; Loos, Ruth J F; Meacham, Stuart; Medland, Sarah E; Meisinger, Christa; Memari, Yasin; Mihailov, Evelin; Miller, Kathy; Moffatt, Miriam F; Nauck, Matthias; Novatchkova, Maria; Nutile, Teresa; Olafsson, Isleifur; Onundarson, Pall T; Parracciani, Debora; Penninx, Brenda W; Perseu, Lucia; Piga, Antonio; Pistis, Giorgio; Pouta, Anneli; Puc, Ursula; Raitakari, Olli; Ring, Susan M; Robino, Antonietta; Ruggiero, Daniela; Ruokonen, Aimo; Saint-Pierre, Aude; Sala, Cinzia; Salumets, Andres; Sambrook, Jennifer; Schepers, Hein; Schmidt, Carsten Oliver; Silljé, Herman H W; Sladek, Rob; Smit, Johannes H; Starr, John M; Stephens, Jonathan; Sulem, Patrick; Tanaka, Toshiko; Thorsteinsdottir, Unnur; Tragante, Vinicius; van Gilst, Wiek H; van Pelt, L Joost; van Veldhuisen, Dirk J; Völker, Uwe; Whitfield, John B; Willemsen, Gonneke; Winkelmann, Bernhard R; Wirnsberger, Gerald; Algra, Ale; Cucca, Francesco; d'Adamo, Adamo Pio; Danesh, John; Deary, Ian J; Dominiczak, Anna F; Elliott, Paul; Fortina, Paolo; Froguel, Philippe; Gasparini, Paolo; Greinacher, Andreas; Hazen, Stanley L; Jarvelin, Marjo-Riitta; Khaw, Kay Tee; Lehtimäki, Terho; Maerz, Winfried; Martin, Nicholas G; Metspalu, Andres; Mitchell, Braxton D; Montgomery, Grant W; Moore, Carmel; Navis, Gerjan; Pirastu, Mario; Pramstaller, Peter P; Ramirez-Solis, Ramiro; Schadt, Eric; Scott, James; Shuldiner, Alan R; Smith, George Davey; Smith, J Gustav; Snieder, Harold; Sorice, Rossella; Spector, Tim D; Stefansson, Kari; Stumvoll, Michael; Tang, W H Wilson; Toniolo, Daniela; Tönjes, Anke; Visscher, Peter M; Vollenweider, Peter; Wareham, Nicholas J; Wolffenbuttel, Bruce H R; Boomsma, Dorret I; Beckmann, Jacques S; Dedoussis, George V; Deloukas, Panos; Ferreira, Manuel A; Sanna, Serena; Uda, Manuela; Hicks, Andrew A; Penninger, Josef Martin; Gieger, Christian; Kooner, Jaspal S; Ouwehand, Willem H; Soranzo, Nicole; Chambers, John C

    2012-01-01

    Anaemia is a chief determinant of global ill health, contributing to cognitive impairment, growth retardation and impaired physical capacity. To understand further the genetic factors influencing red blood cells, we carried out a genome-wide association study of haemoglobin concentration and related

  6. Evaluation of Red Blood Cell Distribution Width in Patients with Cardiac Syndrome X

    Directory of Open Access Journals (Sweden)

    Ping Qing

    2013-01-01

    Full Text Available BACKGROUND: Cardiac syndrome X (CSX is a condition characterized by chest pain with normal coronary arteries. However, its pathogenesis has not fully been understood yet. Red blood cell distribution width (RDW has recently been suggested as a marker of acute and chronic cardiovascular diseases, while no data is available in patients with CSX.

  7. Red blood cell distribution width and 1-year mortality in acute heart failure

    NARCIS (Netherlands)

    van Kimmenade, Roland R. J.; Mohammed, Asim A.; Uthamalingam, Shanmugam; van der Meer, Peter; Felker, G. Michael; Januzzi, James L.

    2010-01-01

    Red blood cell distribution width (RDW) predicts mortality in chronic heart failure (HF) and stable coronary artery disease. The prognostic value of RDW in more acute settings such as acute HF, and its relative prognostic value compared with more established measures such as N-terminal pro-brain nat

  8. Photometric measurements of red blood cell aggregation: light transmission versus light reflectance

    NARCIS (Netherlands)

    Baskurt, O.K.; Uyuklu, M.; Hardeman, M.R.; Meiselman, H.J.

    2009-01-01

    Red blood cell (RBC) aggregation is the reversible and regular clumping in the presence of certain macromolecules. This is a clinically important phenomenon, being significantly enhanced in the presence of acute phase reactants (e. g., fibrinogen). Both light reflection (LR) and light transmission (

  9. Morphological Features of Red Blood Cells in Patients with Severe Concomitant Injury

    Directory of Open Access Journals (Sweden)

    V. V. Moroz

    2013-01-01

    Full Text Available Objective: to reveal changes in the structure and shape of red blood cells depending on blood loss (BL volume in patients with severe concomitant injury (SCI. Subjects and methods. Eighteen patients (9 men, 9 women aged 48.6±16.1 years who had sustained severe concomitant mechanical injury (CMI with different BL volumes and hemodynamic disorders were examined. According to the volume of BL, the patients were divided into two groups: 1 7 victims with a BL volume of < 750 ml (5.7±1.9 ml/kg, grade 1 BL; 2 11 victims with a BL volume of > 2000 ml (37.5±5.1 ml/kg, grade 4 BL. A comparison group consisted of 5 apparently healthy volunteers whose mean age was 26.4±2.7 years. The shapes and sizes of red blood cells were examined by light optical and atomic force microscopy (AFM. To study the composition of red blood cells, ten microliters of whole blood were applied to the slides and red blood cell monolayers were prepared using a V-sampler. The membrane surface was scanned by semicontact resonance AFM. The investigators used NSGL 01-A cantilevers with a resonance frequency in the range of 80200 kHz, a probe radius of 10 nm, 512 and 1024 scanning points, and 100X100 ^m and 10X10 ^m scanning fields. Planar and 3D images were obtained. Results. Calculation of 1000 cells by light optical microscopy and AFM showed significantly different counts of macro- and microcytes in the comparison group. The 100X100-^m field exhibited the following types of red blood cells: discocytes (97.9±1.5% and 96±5%, echinocytes (2.1±0.9% and 3±1%, and squamous cells (0.1±0.02% and 1±0.5%. Within the first 24 hours after injury, the victim group displayed lower normocyte counts and higher counts of macrocytes and microcytes than the control group. AFM in the 100X100-^m field revealed that the victims with SMI when admitted to an intensive care unit exhibited a significant decrease in the counts of discocytes counts and increases in those of echinocytes, stomatocytes

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

    Science.gov (United States)

    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.

  11. Viable bacteria associated with red blood cells and plasma in freshly drawn blood donations

    National Research Council Canada - National Science Library

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

    2015-01-01

    ...% 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...

  12. Susceptibility to fragility test of red blood cell in congenital spherocytosis: an explanation based on surface area principle

    Directory of Open Access Journals (Sweden)

    Viroj Wiwanitkit

    2009-05-01

    Full Text Available "nCongenital spherocytosis is a rare congenital defect with red blood cell membrane abnormality. Based on the author's previous publication on surface area principle, an explanation for the increased fragility of red blood cell in congenital spherocytosis is hereby discussed in this paper.

  13. Transfusion of leukocyte-depleted red blood cells is not a risk factor for nosocomial infections in critically ill children

    NARCIS (Netherlands)

    van der Wal, Judith; van Heerde, Marc; Markhorst, Dick G.; Kneyber, Martin C. J.

    2011-01-01

    Objectives: Transfusion of red blood cells is increasingly linked with adverse outcomes in critically ill children. We tested the hypothesis that leukocyte-depleted red blood cell transfusions were independently associated with increased development of bloodstream infections, ventilator-associated p

  14. Simulation of Deformation and Aggregation of Two Red Blood Cells in a Stenosed Microvessel by Dissipative Particle Dynamics.

    Science.gov (United States)

    Xiao, Lanlan; Liu, Yang; Chen, Shuo; Fu, Bingmei

    2016-12-01

    The motion of two red blood cells in a stenosed microvessel was simulated using dissipative particle dynamics. The effects of intercellular interaction, red blood cell deformability and the initial cell orientation on the deformation and aggregation of the RBCs and on the flow resistance were investigated. The red blood cell membrane was treated as a three-dimensional coarse-grained network model and the intercellular interaction was modeled by the Morse potential based on a depletion-mediated assumption. It is shown that the flow resistance increases dramatically when the red blood cells enter into the stenosis and decreases rapidly as RBCs move away from the stenosis. Particularly, for a pair of stiffer red blood cells with the initial inclination angle of 90°, the maximum value of the flow resistance is larger; while a higher flow resistance can also come from a stronger aggregation. For a pair of stiffer red blood cells moving parallel to the main flow, when their positions are closer to the vessel wall at the upstream of the stenosis, the flow resistance increases due to the migration to the vessel center at the stenosis. In addition, for a pair of red blood cells with the initial inclination angle of 0°, the flow resistance from the aggregate formed by a pair of red blood cells with a larger deformation is higher.

  15. Transfusion rate and prevalence of unexpected red blood cell alloantibodies in women undergoing hysterectomy for benign disease

    DEFF Research Database (Denmark)

    Thoestesen, Lisbeth M; Rasmussen, Kjeld L; Lauszus, Finn F;

    2011-01-01

    To determine transfusion rates, risk factors for transfusion and the prevalence of unexpected red blood cell alloantibodies in women undergoing hysterectomy for benign disease. In addition, we aimed to evaluate the necessity of the pretransfusion testing for red blood cell alloantibodies....

  16. Rheology of red blood cells under flow in highly confined microchannels: I. effect of elasticity.

    Science.gov (United States)

    Lázaro, Guillermo R; Hernández-Machado, Aurora; Pagonabarraga, Ignacio

    2014-10-07

    We analyze the rheology of dilute red blood cell suspensions in pressure driven flows at low Reynolds number, in terms of the morphologies and elasticity of the cells. We focus on narrow channels of width similar to the cell diameter, when the interactions with the walls dominate the cell dynamics. The suspension presents a shear-thinning behaviour, with a Newtonian-behaviour at low shear rates, an intermediate region of strong decay of the suspension viscosity, and an asymptotic regime at high shear rates in which the effective viscosity converges to that of the solvent. We identify the relevant aspects of cell elasticity that contribute to the rheological response of blood at high confinement. In a second paper, we will explore the focusing of red blood cells while flowing at high shear rates and how this effect is controlled by the geometry of the channel.

  17. Influence of in vitro hemolysis on nucleated red blood cells and reticulocyte counts.

    Science.gov (United States)

    Lippi, G; Pavesi, F; Cattabiani, C; Avanzini, P; Pipitone, S

    2013-04-01

    Nucleated red blood cells (NRBCs) and reticulocytes are early and important measures of red blood cells' (RBCs) turnover, but little is known on how spurious hemolysis may affect the reliability of these parameters. Ten EDTA-anticoagulated samples were divided into three aliquots. The first was immediately tested, where-as the others (defined A and B) were mechanically hemolyzed by aspiration 5 and 10 times through a small-gauge needle. RBC, NRBC, and reticulocyte counts were performed on Sysmex XE-2100. An increasing amount of hemolysis was produced in hemolyzed aliquots A and B. The RBC and reticulocyte counts progressively decreased from the nonhemolyzed sample to hemolyzed aliquots 'A' and 'B'. The NRBC count increased in 3 of the 10 samples and decreased in the remaining seven. Hemolysis of venous blood samples may seriously jeopardize NRBC and reticulocyte counts. © 2012 Blackwell Publishing Ltd.

  18. In vivo study of propolis supplementation effects on antioxidative status and red blood cells.

    Science.gov (United States)

    Jasprica, Ivona; Mornar, Ana; Debeljak, Zeljko; Smolcić-Bubalo, Asja; Medić-Sarić, Marica; Mayer, Ljiljana; Romić, Zeljko; Bućan, Kajo; Balog, Tihomir; Sobocanec, Sandra; Sverko, Visnja

    2007-04-04

    In vivo study has been conducted on 47 healthy women and men in order to investigate whether daily intake of powdered propolis extract during 30 days has any influence on the following blood parameters: activity of superoxide dismutase, glutathione peroxidase and catalase, concentration of plasma malondialdehyde, total cholesterol, low- and high-density lipoprotein cholesterol, triglycerides, glucose, uric acid, ferritin and transferrin, together with routine red blood cell parameters. The effect of daily propolis intake seems to be time and gender related. For the men test group after the initial 15 days of propolis treatment, 23.2% (p=0.005) decrease in concentration of malondialdehyde was observed. After 30 days of treatment, statistically significant (p=0.010) 20.9% increase in superoxide dismutase activity and change in some of the red blood cell parameters were detected. For the women test group, the propolis treatment did not induce a change in any of the measured parameters.

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

    Science.gov (United States)

    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.

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

    Directory of Open Access Journals (Sweden)

    Véronique Gaudreault

    Full Text Available 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.

  1. Effect of blood bank storage on the rheological properties of male and female donor red blood cells.

    Science.gov (United States)

    Daly, Amanda; Raval, Jay S; Waters, Jonathan H; Yazer, Mark H; Kameneva, Marina V

    2014-01-01

    It was previously demonstrated that red blood cell (RBC) deformability progressively decreases during storage along with other changes in RBC mechanical properties. Recently, we reported that the magnitude of changes in RBC mechanical fragility associated with blood bank storage in a variety of additive solutions was strongly dependent on the donor gender [15]. Yet, the potential dependence of changes in the deformability and relaxation time of stored blood bank RBCs on donor gender is not known. The objective of this study was to determine the effects of donor gender and blood bank storage on RBC deformability and relaxation time through the measurement of RBC suspension viscoelasticity. Packed RBC units preserved in AS-5 solution from 12 male and 12 female donors (three from each ABO group) were obtained from the local blood center and tested at 1, 4 and 7 weeks of storage at 1-6°C. At each time point, samples were aseptically removed from RBC units and hematocrit was adjusted to 40% before assessment of cell suspension viscoelasticity. RBC suspensions from both genders demonstrated progressive increases (p blood bank storage may reduce tissue perfusion and RBC lifespan in patients receiving blood bank RBCs.

  2. Membrane rigidity of red blood cells parasitized by different strains of Plasmodium falciparum.

    Science.gov (United States)

    Paulitschke, M; Nash, G B

    1993-11-01

    Changes in the structure of parasitized red blood cells may influence their ability to circulate. We have used a micropipette technique to examine the effects of invasion and maturation of Plasmodium falciparum on the membrane rigidity of red blood cells. In the presence of immature, ring form parasites from different laboratory strains, membrane rigidity remained unchanged as compared with uninfected red cells. However, development of more mature pigmented trophozoites caused a marked increase in membrane rigidity. Parasites from knobless strains caused a less-pronounced increase than parasites from knob-positive strains. Using closely synchronized cultures, the dependence of membrane rigidity on parasite maturation was studied in more detail for selected knob-positive and knobless strains. Over a period of 12 hours, while trophozoites developed into schizonts, no further rigidification of the red cell membrane occurred. The increase in membrane rigidity, occurring with the initial development of pigmented trophozoites, may be related to insertion of neoantigens into the red cell surface or modification of native membrane proteins that also occur at this time. In contrast to others, we found no effect of parasite-culture supernatant, harvested at different stages, on the rigidity of uninfected cells exposed to it. Interstrain variation of membrane rigidity could influence pathophysiology in several ways: by promoting margination and cytoadherence of knob-positive strains in the microcirculation, by modulating clearance of parasitized cells by the reticuloendothelial system, and by influencing ischemic complications of severe falciparum malaria.

  3. [HIV transmission via blood transfusions: a study by the Swiss Red Cross blood bank service].

    Science.gov (United States)

    Frey-Wettstein, M; Leder, A; Schütze, M

    1988-02-06

    An inquiry amongst blood transfusion services served to establish at 19 the number of known transfusion associated HIV infections in Switzerland. In 12 cases the transfusion of an anti-HIV positive blood unit could be proven retrospectively, while in 7 cases an HIV-infected blood donor could not be found but the association of the infection with blood transfusion is highly probable by exclusion of other risk factors. All these infections occurred before introduction of anti-HIV screening in Switzerland in November 1985. After this date no new transfusion associated HIV infections have been reported. It is estimated that there are fewer than 170 transfusion associated HIV infections in Switzerland. The probability of infection with AIDS by blood transfusion is less than 1:500,000. Blood transfusion today appears to be as safe as before the emergence of the AIDS epidemic.

  4. Quantification of Cell-Free DNA in Red Blood Cell Units in Different Whole Blood Processing Methods

    Directory of Open Access Journals (Sweden)

    Andrew W. Shih

    2016-01-01

    Full Text Available Background. Whole blood donations in Canada are processed by either the red cell filtration (RCF or whole blood filtration (WBF methods, where leukoreduction is potentially delayed in WBF. Fresh WBF red blood cells (RBCs have been associated with increased in-hospital mortality after transfusion. Cell-free DNA (cfDNA is released by neutrophils prior to leukoreduction, degraded during RBC storage, and is associated with adverse patient outcomes. We explored cfDNA levels in RBCs prepared by RCF and WBF and different storage durations. Methods. Equal numbers of fresh (stored ≤14 days and older RBCs were sampled. cfDNA was quantified by spectrophotometry and PicoGreen. Separate regression models determined the association with processing method and storage duration and their interaction on cfDNA. Results. cfDNA in 120 RBC units (73 RCF, 47 WBF were measured. Using PicoGreen, WBF units overall had higher cfDNA than RCF units (p=0.0010; fresh WBF units had higher cfDNA than fresh RCF units (p=0.0093. Using spectrophotometry, fresh RBC units overall had higher cfDNA than older units (p=0.0031; fresh WBF RBCs had higher cfDNA than older RCF RBCs (p=0.024. Conclusion. Higher cfDNA in fresh WBF was observed compared to older RCF blood. Further study is required for association with patient outcomes.

  5. 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.

    Science.gov (United States)

    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.

  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

    Directory of Open Access Journals (Sweden)

    Marco Marziali

    2014-08-01

    Full Text Available 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.

  7. Cryopreserved red blood cells for pediatric transfusion. Frozen storage of small aliquots in polyvinyl chloride (PVC) plastic bags.

    Science.gov (United States)

    Valeri, C R; Valeri, D A; Gray, A; Melaragno, A J; Vecchione, J J; Dennis, R C; Emerson, C P

    1981-01-01

    Human nonrejuvenated and rejuvenated red bood cells were prepared for cryopreservation and subsequent pediatric transfusion. Glycerol was added to the red blood cells in the primary polyvinyl chloride plastic collection bag to achieve a concentration of 40 per cent W/V. The red blood cells were concentrated by centrifugation, and the supernatant glycerol was discarded. Each glycerolized unit was divided into four equal aliquots in the individual 600-ml bags of a dry quadruple polyvinyl chloride plastic system, and each aliquot was frozen and stored at -80 C. After thawing, sodium chloride solutions were used to wash the aliquots in the IBM Blood Processor 2991-1 or 2991-2 or the Haemonetics Blood Processor 115, and the washed aliquots were stored in a sodium chloride-glucose-phosphate solution at 4 C for 24 hours. Freeze-thaw recovery of the red blood cells was about 97 per cent, and freeze-thaw-wash recovery was about 84 per cent. Twenty-four-hour posttransfusion survival values were about 92 per cent for both nonrejuvenated and indated-rejuvenated red blood cells. Nonrejuvenated red blood cells, those frozen within three to five days of collection without biochemical modification, had normal oxygen transport function at the time of transfusion; rejuvenated red blood cells, those biochemically treated with PIGPA Solution A after three to five days of storage at 4 C, had improved oxygen transport function at the time of transfusion.

  8. Using qualitative research methods in biomedical innovation: the case of cultured red blood cells for transfusion.

    Science.gov (United States)

    Lyall, Catherine; King, Emma

    2016-05-11

    Qualitative research has a key role to play in biomedical innovation projects. This article focuses on the appropriate use of robust social science methodologies (primarily focus group studies) for identifying the public's willingness and preference for emerging medical technologies. Our study was part of the BloodPharma project (now known as the Novosang project) to deliver industrially generated red blood cells for transfusion. Previous work on blood substitutes shows that the public prefers donated human blood. However, no research has been conducted concerning attitudes to stem cell derived red blood cells. Qualitative research methods including interviews and focus groups provide the methodological context for this paper. Focus groups were used to elicit views from sub-sections of the UK population about the potential use of such cultured red blood cells. We reflect on the appropriateness of that methodology in the context of the BloodPharma project. Findings are in the form of lessons transferable to other interdisciplinary, science-led teams about what a social science dimension can bring; why qualitative research should be included; and how it can be used effectively. Qualitative data collection offers the strength of exploring ambivalence and investigating the reasons for views, but not necessarily their prevalence in wider society. The inherent value of a qualitative method, such as focus groups, therefore lies in its ability to uncover new information. This contrasts with a quantitative approach to simply 'measuring' public opinion on a topic about which participants may have little prior knowledge. We discuss a number of challenges including: appropriate roles for embedded social scientists and the intricacies of doing upstream engagement as well as some of the design issues and limitations associated with the focus group method.

  9. NEUROTROPIC AND DIURETIC ACTIVITY OF THICK EXTRACT OF THE BLOOD-RED HAWTHORN’S FRUITS

    Directory of Open Access Journals (Sweden)

    V. A. Kurkin

    2015-01-01

    Full Text Available Blood-red hawthorn (Crataegi fructus are a popular cardiotonic herbal materials, which widely used in medical practice in our country and abroad. In order to prevent diseases of the cardiovascular system is appropriate to prescribe herbal medicines, because they combine the breadth and softness of therapeutic action, along with the absence of a significant number of side effects and contraindications.The purpose was to study diuretic and antidepressant activity of thick fruit extract of blood-red hawthorn.Material and methods. Under laboratory conditions we obtained a thick extract of blood-red hawthorn fruits. This phytopharmaceutical was studied by us for any diuretic and antidepressant activity. Investiga- tions were carried out on white rats of both sexes weighing 200–220 g. Each experimental group consist- ed of ten animals. Study drug was administered intragastrically by stomach tube. Control in both cases served as purified water. For determination of diuretic activity, we used a thick extract of hawthorn fruits in a dose of 20 mg/kg against the background of the water load in the amount of 3% of body weight of the animal. Reference preparation was chosen dichlorthiazid 20 mg/kg. It was administered once. After ad- ministration the animals were placed in metabolic cages for urine collection for 24 hours. The study de- termined diuresis, natriuresis, kaliuresis, and kreatininuresis for 4 h and 24 h of the experiment. On the day of the experiment the animals of the control group was administered water load of 3%, and experi- enced – intragastrically drug in an identical amount. Animals were placed in a metabolic cage for a day. Collected 4 h and 24-h urine sample. Determined by renal excretion of water was recorded concentration of sodium and potassium by flame photometry in the fiery liquid analyzer PAG-1, creatinine – colorimet- ric method for photocolorimeter CFC-3. For determining antidepressant activity we used a thick hawthorn

  10. In vitro combinations of red blood cell, plasma and platelet components evaluated by thromboelastography.

    Science.gov (United States)

    Agren, Anna; Edgren, Gustaf; Kardell, Malin; Ostlund, Anders; Wikman, Agneta Taune

    2014-10-01

    Thromboelastography is increasingly used to evaluate coagulation in massively bleeding patients. The aim of this study was to investigate how different combinations of blood components affect in vitro whole blood clotting measured by thromboelastography. Packed red blood cells, plasma and platelets from fresh and old blood components were mixed in vitro, in proportions of 4:4:1, 5:5:2, 8:4:1 and 2:1:0, and analysed with thromboelastography. For the ratio 4:4:1 the experiment was done at both 37 °C and 32 °C. Thromboelastography curves were within normal reference values for the blood component proportions of 4:4:1 and 5:5:2. For 8:4:1, the angle and maximal amplitude were reduced below normal values, indicating low levels of fibrinogen and/or platelets. For the 2:1:0 proportion, all parameters were affected resulting in severely impaired in vitro clot formation. The reaction-time, reflecting the coagulation factor-dependent, initial clot formation, was slightly increased at a low temperature. Prolonged storage of the components did not affect the curve. With the introduction of guidelines on the management of massive bleeding it is important to have tools for the assessment of the new protocols. In vitro evaluation of mixtures of packed red blood cells, plasma and platelets by thromboelastography may be relevant in the prediction of in vivo clot formation and haemostasis.

  11. Blood smear

    Science.gov (United States)

    ... some red blood cells shaped like spheres ( hereditary spherocytosis ) Increased breakdown of RBCs Presence of RBCs with ... normal Red blood cells, elliptocytosis Red blood cells, spherocytosis Acute lymphocytic leukemia - photomicrograph Red blood cells, multiple ...

  12. Mortality risk is dose-dependent on the number of packed red blood cell transfused after coronary artery bypass graft

    OpenAIRE

    dos Santos, Antônio Alceu; de Sousa, Alexandre Gonçalves; Piotto, Raquel Ferrari; Pedroso, Juan Carlos Montano [UNIFESP

    2013-01-01

    Introduction Transfusions of one or more packed red blood cells is a widely strategy used in cardiac surgery, even after several evidences of increased morbidity and mortality. The world's blood shortage is also already evident. Objective To assess whether the risk of mortality is dose-de>pendent on the number of packed red blood cells transfused after coronary artery bypass graft. Methods Between June 2009 and July 2010, were analyzed 3010 patients: transfused and non-transfused. Transfused ...

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

    Science.gov (United States)

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

    Science.gov (United States)

    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

    2015-05-01

    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.

  15. Zebrafish etv7 regulates red blood cell development through the cholesterol synthesis pathway

    Directory of Open Access Journals (Sweden)

    Anita M. Quintana

    2014-02-01

    Full Text Available ETV7 is a human oncoprotein that cooperates with Eμ-MYC to promote pre-B-cell leukemia in mice. It is normally expressed in the bone marrow and fetal liver and is upregulated in primary leukemia, suggesting that it is involved in proper hematopoiesis and leukemogenesis. ETV7 has been deleted in most rodents, but is conserved in all other vertebrates, including the zebrafish, Danio rerio. In this report, we characterize the function of the zebrafish etv7 gene during erythropoiesis. Our results demonstrate that etv7 regulates the expression of the zebrafish lanosterol synthase (lss gene, an essential gene in the cholesterol synthesis pathway. Furthermore, morpholino knockdown of etv7 leads to loss of hemoglobin-containing red blood cells, a phenotype that can be rescued by injection of exogenous cholesterol. We conclude that etv7 is essential for normal red blood cell development through regulation of the lss gene and the cholesterol synthesis pathway.

  16. [Detection of fetal nucleated red blood cells in the maternal circulation by Kleihauer test].

    Science.gov (United States)

    Liu, Wei-Yu; Jin, Chun-Lian; Liu, Li-Ying; Lin, Chang-Kun; Wang, Yan; Sun, Kai-Lai

    2007-03-01

    Maternal blood was obtained from 18 pregnant women at 7 to 25 weeks of gestation. After Percoll discontinuous density gradient centifugation, the fetal nucleated red blood cells (NRBCs) were stained with Kleihauer test. Positive fetal cells appeared with an intense red cytoplasmic staining while maternal cells with adult haemoglobin were colourless. Individual positive NRBC was collected by micromanipulator and whole genome amplification was then performed to determine sex and STR status. This allowed the simultaneous verification of the fetal origin of NRBC and prenatal diagnosis of genetic diseases. The non-invasive prenatal genetic diagnosis of 9 fetuses at high risk of Duchenne muscular dystrophy (DMD) was completed successfully. The Kleihauer test is a rapid, simple and direct chemical staining method to select fetal cells and can be applied in prenatal diagnosis.

  17. Loss of blood group A in acute leukemia. Morphologic and biochemical studies of red cells.

    Science.gov (United States)

    Atkinson, J B; Tanley, P C; Wallas, C H

    1987-01-01

    A patient with blood type A had acute myelomonocytic leukemia; his red cells (RBCs) typed as O and his serum had anti-B. RBC membranes were isolated from the patient as well as from controls with group A and O red cells. The membranes were incubated with uridine diphosphate (UDP)-N-acetyl-D-14C galactosamine in plasma from the patient and controls with group A and O red cells. RBC membranes from the patient behaved normally in that they incorporated the terminal carbohydrate responsible for blood group A activity. Scanning electron microscopy showed that the patient's RBCs had striking morphologic changes, with marked crenation and numerous knisocytes and dacryocytes. It was concluded that loss of the A antigen in this patient was not due to an abnormality of the enzyme required to convert H substance to A substance. It was postulated that weakening of the A antigen in some patients with leukemia may be related to a steric modification associated with abnormal red cell morphology.

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

    Science.gov (United States)

    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.

  19. The Effects of Morphine Sulfate on Agglutination, Clot Formation and Hemolysis in Packed Red Blood Cells

    Science.gov (United States)

    2007-11-02

    THE EFFECTS OF MORPHINE SULFATE ON AGGLUTINATION , CLOT FORMATION AND HEMOLYSIS IN PACKED RED BLOOD CELLS 6. AUTHOR(S) CAPT ESTAVILLO BRIAN K 7...ANSI Std8 239.18 Designed using Perform Pro, WHS/DIOR, Oct 94 THE EFFECTS OF MORPHINE SULFATE ON AGGLUTINATION , CLOT FORMATION AND HEMOLYSIS IN PACKED...that the use of any copyrighted material in the thesis entitled: "THE EFFECTS OF MORPHINE SULFATE ON AGGLUTINATION , CLOT FORMATION AND HEMOLYSIS IN

  20. Clinical application of whole blood red cell distribution width in lung cancer metastasis

    Institute of Scientific and Technical Information of China (English)

    徐阳飏

    2014-01-01

    Objective To investigate the clinical value of whole blood red cell distribution width(RDW)in discriminating lung cancer metastasis.Methods A retropective analysis was conducted on the patients who were initially diagnosed as primary lung cancer.A total of 525 patients were included for analysis between January 2012 and July2013,stratified by different stages and metastasis scenarios.RDW data was investigated.Kruskal-Wallis H tests

  1. Adverse effects to transfusion with red donor blood cells are frequent

    DEFF Research Database (Denmark)

    Pommergaard, Hans-Christian; Nørgaard, Astrid; Burcharth, Jakob

    2014-01-01

    Adverse effects to transfusion with red donor blood cells are potentially life-threatening. Due to screening, transmission of infectious diseases has decreased; however, the risk is still present. Various immune reactions are common including simple allergic reactions as well as devastating...... conditions such as transfusion-related acute lung injury and circulatory overload in patients with heart disease. Knowledge of the clinical signs of transfusion-related complications is important for clinicians in order to provide the best possible treatment....

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

    Science.gov (United States)

    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. Population red blood cell folate concentrations for prevention of neural tube defects: bayesian model

    OpenAIRE

    MOLLOY, ANNE

    2014-01-01

    PUBLISHED OBJECTIVE: To determine an optimal population red blood cell (RBC) folate concentration for the prevention of neural tube birth defects. DESIGN: Bayesian model. SETTING: Data from two population based studies in China. PARTICIPANTS: 247,831 participants in a prospective community intervention project in China (1993-95) to prevent neural tube defects with 400 μg/day folic acid supplementation and 1194 participants in a population based randomized trial (20...

  4. T-matrix computations of light scattering by red blood cells

    OpenAIRE

    Nilsson, Annika M. K.; Alsholm, Peter; Karlsson, Anders; Andersson-Engels, Stefan

    1998-01-01

    The electromagnetic far field, as well as near field, originating from light interaction with a red blood cell (RBC) volume equivalent spheroid, were analyzed utilizing T-matrix theory. This method is a powerful tool which enables the influence of cell shape on the angular distribution of scattered light to be studied. General observations were that the three-dimensional shape, as well as optical thickness apparent to the incident field, affect the forward scattering. The ba...

  5. Salidroside as a Novel Protective Agent to Improve Red Blood Cell Cryopreservation

    OpenAIRE

    Alotaibi, Noha A. S.; Slater, Nigel K.H.; Rahmoune, Hassan

    2016-01-01

    Glycerol and trehalose have been widely examined as protective agents in the cryopreservation of red blood cells (RBCs). However, the effectiveness of these reagents alone on cell viability is moderate. Here, the addition of salidroside attenuated oxidative damage of sheep RBCs prior to and post cryostorage. The supplementation of salidroside to the cryopreservation media containing 10% glycerol improved RBC survival by approximately 61.1?4.8% vs 37.9?4.6%. A smaller effect was seen in RBCs c...

  6. Salidroside as a Novel Protective Agent to Improve Red Blood Cell Cryopreservation

    OpenAIRE

    Alotaibi, Noha A. S.; Slater, Nigel K.H.; Rahmoune, Hassan

    2016-01-01

    This is the final version of the article. It first appeared from the Public Library of Science via https://doi.org/10.1371/journal.pone.0162748 Glycerol and trehalose have been widely examined as protective agents in the cryopreservation of red blood cells (RBCs). However, the effectiveness of these reagents alone on cell viability is moderate. Here, the addition of salidroside attenuated oxidative damage of sheep RBCs prior to and post cryostorage. The supplementation of salidroside to th...

  7. Multifocal peritoneal splenosis in Tc-99m-labeled heat-denatured red blood cell scintigraphy

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Min Ki; Hwang, Kyung Hoon; Choe, Won Sick [Gachon University Gil Medical Center, Incheon (Korea, Republic of)

    2006-06-15

    A 44-year-old man with a past medical history of splenectomy came to hospital because of epigastric pain abdominopelvic computed tomography(CT) showed a soft tissue mass and multifocal variable-sized nodules as well as finding suggestive of cholecystitis. Subsequently, he underwent Tc-99m-labeled heat- denatured red blood cell(RBC) scintigraphy to evaluate the mass and nodules. The scintigraphy confirmed multifocal peritoneal splenosis in the abdominopelvic cavity.

  8. Image-based red blood cell counter for multiple species of wild and domestic animals

    Directory of Open Access Journals (Sweden)

    C.R.M. Mauricio

    Full Text Available ABSTRACT RBC count plays an important role in animal diagnosis. Despite the many technologies available in different automated hematology analyzers, when it comes to the blood of wild animals it is still difficult to find an easy and affordable solution for multiple species. This study aims to evaluate the proposed automatic red blood cell counter. Blood samples (1 ocelot - Leopardus pardalis, 1 monkey - Cebus apella, 1 coati - Nasua nasua, 62 dogs - Canis familiaris, and 5 horses - Equus caballus were analyzed using three methods: 1-manual count, 2-automatic count by image, and 3-semi-automatic count by image; blood from dogs and horses were also analyzed by a fourth method: 4-automatic count by impedance. The counts in methods 2 and 3 were produced by the proposed red blood cell counter. Results were compared using Pearson's correlation and plots with different methods as the criterion standard. RBC counts in methods 1, 2, and 3 correlated very well with those in the method 4 (r ≥ 0.94. RBC counts produced by method 2 were highly correlated with method 3 (r = 0.998. The results indicate that the proposed method can be used as an automatic or semi-automatic counting method in clinics that are currently using the manual method for RBC assessment.

  9. Effect of particle collisions and aggregation on red blood cell passage through a bifurcation.

    Science.gov (United States)

    Chesnutt, J K W; Marshall, J S

    2009-12-01

    Blood flow through bifurcating vessels in the microvasculature leads to uneven distribution of red blood cells (RBC) in the downstream channels when the channels have different sizes or the flow rates through the channels are different. This phenomenon, known as plasma skimming, is responsible for the large variation in hematocrit throughout the circulatory system. Furthermore, the strong streamline curvature present within bifurcations leads to frequent collisions between the blood elements (red and white blood cells and platelets) and the vessel walls, as well as a rearrangement of the distribution of the blood elements in the channels downstream of the bifurcation. Computational models of bifurcation flows typically neglect collision and adhesion of RBCs with each other. In this paper, we use a new type of discrete-element model to investigate the effect of particle-particle collisions and RBC aggregation on modeling of plasma skimming in bifurcations. Cases are examined with and without RBC adhesion and for different hematocrit values, including validation against previous computational results. Results show significant plasma skimming in the low-flow daughter branch and an increase in fractional particle flux with increased hematocrit, as in experimental studies. Accounting for particle-particle collisions leads to a considerable increase in collision rate of particles with the vessel wall. Particles are found to approximately follow fluid velocity streamlines, and consequently particle-particle collisions and aggregation do not significantly affect plasma skimming.

  10. EFFECT OF ELECTROACUPUNCTURE ON RED BLOOD CELL IMMUNE AND T-CELL SUBGROUP IN THE RAT

    Institute of Scientific and Technical Information of China (English)

    高巍; 黄裕新; 陈洪; 孙大勇; 张洪新

    2000-01-01

    In the present study, the effect of electroacupuncture (EA) on immune system was observed in the rat by using micro- whole blood direct immunofluorescence Staining assay to detect changes of the peripheral blood T lymphocyte subgroup and employing red blood cell (RBC) C3b receptor- yeast rosette test and red blood cell-IC rosette test to analyze erythrocytic immune function. Resuits showed that after EA of “Zusanli” (ST 36), CD4+, RBC-C3bRR and RBC-ICR in the peripheral blood of the normal rats increased significantly while CDs+ had no any considerable changes and a positive correlation between CD~ and RBC-C3bRR was found. In immtttaosuppression model rats, the values of CD4+ and RBC-C3bRR were obviously lower than those of the normal control group while CD8+ had no any striking changes; but after EA treatment, there were no evident differences between EAgroup and normal control group in the above-mentioned indexes. There were also no any significant differences between non-acupoint group and normal control group in those indexes. Results suggest that EA of “Zusanli” (ST 36) can raise T cell immune function and RBC adhesion function in both normal rats and immunosuppression model rats, both of which present a positive correlation.

  11. EFFECT OF ELECTROACUPUNCTURE ON RED BLOOD CELL IMMUNE AND T-CELL SUBGROUP IN THE RAT

    Institute of Scientific and Technical Information of China (English)

    GaoWei; HuangYuxin; ChenHong; SunDayong; ZhangHongxin

    2000-01-01

    In the present study, the effect of electroacupuncture (EA) on immune system was observed in the rat by using micro- whole blood direct immunofluoreseence Staining assay to detect changes of the peripheral blood T lymphocyte subgroup and employing red blood cell (RBC) C3b receptor- yeast rosette test and red blood cell-IC rosette test to analyze erythroeytic immune function. Results showed that after EA of “Zusanli” (ST 36), CD4+, RBC-C3bRR and RBC-ICR in the peripheral blood of the normal rats increased significantly while CD8+ had no any considerable changes and a positive correlation between CD4+ and RBC-C3bRR was found. In immuoosuppression model rats, the values of CD4+ and RBC-C3bRR were obviously lower than those of the normal control group while CD8+ had no any striking changes; but after EA treatment, there were no evident differences between EA group and normal control group in the above-mentioned indexes. There were also no any significant differences between non-acupoint group and normal control group in those indexes. Results suggest that EA of “Zusanli” (ST 36) can raise T cell immune function and RBC adhesion function in both normal rats and immunosuppression model rats, both of which present a positive correlation.

  12. Fragmented red cells reference range (Sysmex XN(®) automated blood cell counter).

    Science.gov (United States)

    Lesesve, Jean-François; Daigney, Amandine; Henry, Sylvain; Speyer, Elodie

    2015-01-01

    Fragmented red cells (FRCs) is a new parameter automatedly determined by recent blood cell counters. Their count might be of interest because FRCs are supposed to reflect schistocytes counts measured on a stained peripheral blood smear observed under the microscope. But FRCs depend from the technical procedure used to detect them and thus reference ranges are device-dependent. The XN-9000(®) is one of the last model from Sysmex series. We aimed to establish reference range for FRCs, from 2389 controls. The mean ± SD was 0.32% ± 0.81, the median 0.02% (95% confidence interval ot the mean: 0.29-0.35%). We observed that the percentage of red blood cells with less than 17 pg of hemoglobin content (Hypo-He) was correlated to FRC increase, Hypo-He increase resulting in spurious FRCs majoration. FRCs reference range should be useful for: 1) laboratory staff in order to select which blood smears to check optically; 2) Sysmex company to set-up more optimal rules proposed with the counter (automated making of blood smear).

  13. Species determination using the red blood cells morphometry in domestic animals

    Directory of Open Access Journals (Sweden)

    Nezar Adili

    2016-09-01

    Full Text Available Aim: This investigation is placed in the context of continuity of a preliminary study already published; it was conducted in cattle, sheep, goats, horses, and dogs; the main aim is to reveal and develop criteria for the animal species determination based on the morphometric parameters of red blood cells. Materials and Methods: Blood samples were taken from the jugular vein; and the smears were confectioned on slides immediately after the blood collection and stained according to the May-Gründwald Giemsa method. For the morphometric study, three parameters were considered which are: The diameter, the circumference, and the surface of erythrocytes; and measurements were achieved using the OPTIKATM Vision Pro software. Statistical analysis was performed by both analysis of variances and Student’s t analytical tests. Results: The recorded data showed that the three morphometric parameters of red blood cells are higher in dogs followed, respectively, by those of horses, cattle, and sheep, whereas, the goats have the lowest ones. In addition, the obtained results allowed us to propose new reference values for the circumference and the surface of erythrocyte in considered species. Conclusion: This investigation permit concluding that from a drop of blood it is possible to characterize the different animal species, taking into account the diameter, the circumference, and the surface of erythrocytes.

  14. Short report: screening for Trypanosoma cruzi in the blood supply by the Red Cross blood bank in Quito, Ecuador.

    Science.gov (United States)

    Grijalva, M J; Chiriboga, R; Racines, J R; Escalante, L; Rowland, E C

    1997-12-01

    The status of Chagas' disease in Ecuador is not clear. In response to reports suggesting the possibility of transfusion-associated transmission of Chagas' disease in the blood bank in Quito, the Ecuadorian Red Cross in collaboration with the Instituto Nacional de Higiene, Zona Norte and the Tropical Disease Institute of Ohio University implemented a pilot Chagas' disease screening of the donated blood in the Quito blood bank. The results of the screening showed a low incidence of seropositivity among the donors (0.01% in 1994, 0.04% in 1995, and 0.02% in 1996) to the Quito blood bank and a higher seropositivity in samples donated to smaller blood banks (0.4% in 1994, 0.28% in 1995, and 0.13% in 1996) located in areas considered endemic, as well as from at least two areas previously considered nonendemic for Chagas' disease. This report highlights the need for a comprehensive evaluation of the prevalence and distribution of Chagas' disease in Ecuador.

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

    Science.gov (United States)

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

    2016-05-03

    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.

  16. RED-BLOOD-CELL TRANSFUSIONS FOR TOTAL HIP-REPLACEMENT IN A REGIONAL-HOSPITAL - A 6-YEAR ANALYSIS

    NARCIS (Netherlands)

    Biesma, Douwe H.; van Iperen, Charlotte E.; Kraaijenhagen, Rob J.; Marx, Joannes J. M.; van de Wiel, Harry B. M.; van De Wiel, Albert

    1994-01-01

    To evaluate changes in the need for homologous blood and to assess the imp act of autologous blood transfusion, red cell transfusions in unilateral total hip replacement surgery, performed electively in the period 1986-1991, were studied in a regional hospital. Transfusion data, perioperative blood

  17. RED BLOOD CELL AND WHOLE BLOOD GLUTATHIONE REDOX STATUS IN ENDURANCE-TRAINED MEN FOLLOWING A SKI MARATHON

    Directory of Open Access Journals (Sweden)

    Eve Unt

    2008-09-01

    Full Text Available The aim of the present study was to evaluate the changes in glutathione redox ratio (GSSG·GSH-1 in red blood cells (RBCs and whole blood in well-trained men following a ski marathon. 16 male subjects (27.0 ± 4.7 yrs, 1.81 ± 0.06 m, 77.6 ± 9.6 kg, VO2max 66.2 ± 5.7 ml·kg-1·min-1 were examined before the competition (pre- COMP, after the competition (post-COMP and during an 18-hour recovery period (RECOV. There was a slight decrease in reduced glutathione (GSH in blood and in RBCs in post-COMP. During RECOV, the GSH level in blood was reduced, the GSH level in RBCs was significantly elevated (a statistically significant difference as compared to the pre-COMP level. The post-COMP GSSG·GSH-1 in full blood did not increase significantly, but its increase was statistically significant during the 18-hour recovery period. During the post-COMP and RECOV, the GSSG·GSH-1 in RBCs slightly decreased in comparison with the pre-COMP. Vitamin C concentration in serum increased in post-COMP (49% vs. pre- COMP and decreased to the baseline level during RECOV. In conclusion, our data show that acute exercise slightly increases the GSSG·GSH-1 in whole blood, while GSSG·GSH-1 in RBCs significantly decreases. Thus, exercise-related changes in the non-enzymatic components of the glutathione system (GSSG and GSH in whole blood and RBCs are not identical

  18. Microwave Blood Thawing: Biochemical Analysis of Small Samples of Thawed Red Blood Cells.

    Science.gov (United States)

    1984-01-01

    lactate + NAD+ ( Lehninger , 1977) The large increase in pyruvate observed at 6 hours post-wash was most likely due to the large lactate concentrations at...Storage of Blood. London: Academic Press. Lehninger , A.L. 1977. Biochemistry. New York: Worth Publishers, Inc. Lewis, G.P. 1965. Method using o-tolidine

  19. SMIM1 underlies the Vel blood group and influences red blood cell traits

    DEFF Research Database (Denmark)

    Cvejic, Ana; Haer-Wigman, Lonneke; Stephens, Jonathan C

    2013-01-01

    The blood group Vel was discovered 60 years ago, but the underlying gene is unknown. Individuals negative for the Vel antigen are rare and are required for the safe transfusion of patients with antibodies to Vel. To identify the responsible gene, we sequenced the exomes of five individuals negati...

  20. The Proteome of the Red Blood Cell: An Auspicious Source of New Insights into Membrane-Centered Regulation of Homeostasis.

    Science.gov (United States)

    Bosman, Giel J C G M

    2016-11-25

    During the past decade, the hand-in-hand development of biotechnology and bioinformatics has enabled a view of the function of the red blood cell that surpasses the supply of oxygen and removal of carbon dioxide. Comparative proteomic inventories have yielded new clues to the processes that regulate membrane-cytoskeleton interactions in health and disease, and to the ways by which red blood cells communicate with their environment. In addition, proteomic data have revealed the possibility that many, hitherto unsuspected, metabolic processes are active in the red blood cell cytoplasm. Recent metabolomic studies have confirmed and expanded this notion. Taken together, the presently available data point towards the red blood cell membrane as the hub at which all regulatory processes come together. Thus, alterations in the association of regulatory proteins with the cell membrane may be a sine qua non for the functional relevance of any postulated molecular mechanism. From this perspective, comparative proteomics centered on the red blood cell membrane constitute a powerful tool for the identification and elucidation of the physiologically and pathologically relevant pathways that regulate red blood cell homeostasis. Additionally, this perspective provides a focus for the interpretation of metabolomic studies, especially in the development of biomarkers in the blood.

  1. Laser-diffraction slit rheometer to measure red blood cell deformability

    Science.gov (United States)

    Shin, S.; Ku, Y. H.; Park, M. S.; Moon, S. Y.; Jang, J. H.; Suh, J. S.

    2004-02-01

    The laser-diffraction technique has been applied to design a slit rheometer for measuring red blood cell deformability over a range of shear stress. Flow-rate and pressure-drop measurements are replaced with a measurement of pressure variation with time. Using a precision pressure transducer, one can measure the variation of pressure in the vacuum chamber, p(t), from which the shear stress and shear rate are mathematically calculated. In addition, a laser beam traverses a diluted blood suspension and is diffracted by red blood cells (RBCs) in the volume. The diffraction patterns are captured by a charge coupled device-video camera, linked to a frame grabber integrated with a computer. When deforming under decreasing shear stress, RBCs change gradually from the prolate ellipsoid towards a circular biconcave morphology. The elongation index as a measure of RBC deformability is determined from an isointensity curve in the diffraction pattern using an ellipse-fitting program. The advantages of this design are simplicity, i.e., ease of operation and no moving parts, low cost, short operating time, and the disposable kit which is in contact with the blood sample.

  2. Radiolabeled red blood cells for the direct measurement of the blood flow kinetics in experimental tumors after photodynamic therapy

    Science.gov (United States)

    Paquette, Benoit; Rousseau, Jacques; Ouellet, Rene; van Lier, Johan E.

    1991-06-01

    Red blood cells from BALB/c mice were labeled with short-lived (gamma) -emitting 99mTc and injected in EMT-6 tumor-bearing animals as a probe for the blood circulation. 99mTc-concentrations in light-exposed versus non-treated tumors were established for different photosensitizers at various dye doses and time intervals post-photodynamic therapy. At minimal dye doses for tumor cure, Photofrin IITM induced a doubling of the tumor radioactivity within the first hour post-PDT, followed by a marked decrease in the 99mTc-concentration at 24 hours post PDT. This pattern is characteristic of extensive hemorrhage followed by occlusion of the blood vessels. Under similar conditions the mono- and tetrasulfonated zinc phthalocyanines induced tumor response without prolonged effects on the tumor radioactivity levels. Accordingly, with the latter sensitizers, indirect cell kill via obstruction of the blood supply does not appear to constitute a major factor in eliciting a tumor response.

  3. Maternal red blood cell alloantibodies identified in blood samples obtained from Iranian pregnant women: the first population study in Iran.

    Science.gov (United States)

    Shahverdi, Ehsan; Moghaddam, Mostafa; Gorzin, Fateme

    2017-01-01

    The objective was to determine the frequency of occurrence of alloantibodies among pregnant women in Iran. This was a prospective cross-sectional study, which was carried out in the immunohematology reference laboratory of the Iranian Blood Transfusion Organization in Tehran, Iran, in 2008 to 2015. Screening and identification of red blood cell (RBC) alloantibodies was done on the sera of 7340 pregnant females using the standard tube method and gel column agglutination technique. Alloantibodies were identified in the serum of 332 of the 7340 (4.5%) pregnant women. A total of 410 antibodies were detected in 332 positive maternal serum samples with no previous history of blood transfusion. Anti-D was the most common antibody accounting for 70.5% of all the antibodies formed in D- women. The incidence of specific alloimmunization other than Rh group was 14.4%. We concluded that the alloimmunization rate was high in comparison with wide pattern in previous studies. In Iran, like other developing countries, alloimmunization screening tests are performed only to detect anti-D in pregnant D- women. This high rate of alloimmunization, quite possibly, is due to the fact that the majority of blood samples came from pregnant women known to have previous obstetric problems. However, we suggest that RBC antibody screening tests should be extended to all D+ women. © 2016 AABB.

  4. Controlled lecithin release from a hierarchical architecture on blood-contacting surface to reduce hemolysis of stored red blood cells.

    Science.gov (United States)

    Shi, Qiang; Fan, Qunfu; Ye, Wei; Hou, Jianwen; Wong, Shing-Chung; Xu, Xiaodong; Yin, Jinghua

    2014-06-25

    Hemolysis of red blood cells (RBCs) caused by implant devices in vivo and nonpolyvinyl chloride containers for RBC preservation in vitro has recently gained much attention. To develop blood-contacting biomaterials with long-term antihemolysis capability, we present a facile method to construct a hydrophilic, 3D hierarchical architecture on the surface of styrene-b-(ethylene-co-butylene)-b-styrene elastomer (SEBS) with poly(ethylene oxide) (PEO)/lecithin nano/microfibers. The strategy is based on electrospinning of PEO/lecithin fibers onto the surface of poly [poly(ethylene glycol) methyl ether methacrylate] [P(PEGMEMA)]-modified SEBS, which renders SEBS suitable for RBC storage in vitro. We demonstrate that the constructed 3D architecture is composed of hydrophilic micro- and nanofibers, which transforms to hydrogel networks immediately in blood; the controlled release of lecithin is achieved by gradual dissolution of PEO/lecithin hydrogels, and the interaction of lecithin with RBCs maintains the membrane flexibility and normal RBC shape. Thus, the blood-contacting surface reduces both mechanical and oxidative damage to RBC membranes, resulting in low hemolysis of preserved RBCs. This work not only paves new way to fabricate high hemocompatible biomaterials for RBC storage in vitro, but provides basic principles to design and develop antihemolysis biomaterials for implantation in vivo.

  5. Levels of red blood cell fatty acids in patients with psychosis, their unaffected siblings, and healthy controls

    NARCIS (Netherlands)

    S. Medema (Suzanne); L.P.C.M. Mocking (Remco); M. Koëter (Maarten); F.M. Vaz (Frédéric M.); C. Meijer (Carin); L. Haan (Lieuwe); N.J.M. De Van Beveren (Nico J. M.); R. Kahn; L. de Haan (Lieuwe); J. Van Os (Jim); D. Wiersma (Durk); R. Bruggeman (Richard); W. Cahn (Wiepke); I. Myin-Germeys (Inez)

    2016-01-01

    textabstractBackground: Two recent meta- Analyses showed decreased red blood cell (RBC) polyunsaturated fatty acids (FA) in schizophrenia and related disorders. However, both these meta- Analyses report considerable heterogeneity, probably related to differences in patient samples between studies. H

  6. The dual roles of red blood cells in tissue oxygen delivery

    DEFF Research Database (Denmark)

    Jensen, Frank Bo

    2009-01-01

    Vertebrate red blood cells (RBCs) seem to serve tissue oxygen delivery in two distinct ways. Firstly, RBCs enable the adequate transport of O2 between respiratory surfaces and metabolizing tissues by means of their high intracellular concentration of hemoglobin (Hb), appropriate allosteric...... that enhance blood flow in hypoxic tissues. This latter function could be important in matching tissue O2 delivery with local O2 demand. Three main mechanisms by which RBCs can regulate their own distribution in the microcirculation have been proposed. These are: (1) deoxygenation-dependent release of ATP from...... with regard to their mechanisms, experimental evidence in their support and details that remain unresolved. The prime focus is on human/mammalian models, where most evidence for a role of erythrocyte ATP and NO release in blood flow regulation have accumulated. Information from other vertebrate groups...

  7. Local membrane deformations activate Ca2+-dependent K+ and anionic currents in intact human red blood cells

    DEFF Research Database (Denmark)

    Dyrda, Agnieszka; Cytlak, Urszula; Ciuraszkiewicz, Anna;

    2010-01-01

    -activated transient PCa observed here under local membrane deformation is a likely contributor to the Ca(2+)-mediated effects observed during the normal aging process of red blood cells, and to the increased Ca(2+) content of red cells in certain hereditary anemias such as thalassemia and sickle cell anemia....

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

    Directory of Open Access Journals (Sweden)

    Joanna F Flatt

    2014-06-01

    Full Text Available 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. Further study of stored red blood cells from donors known to have a high or low-rate of cation leak will shed more light on the relationship between cation gradients and the manifestation of the various elements of the storage lesion.

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

    Science.gov (United States)

    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

  10. Design of microfluidic channels for magnetic separation of malaria-infected red blood cells

    Science.gov (United States)

    Wu, Wei-Tao; Martin, Andrea Blue; Gandini, Alberto; Aubry, Nadine; Massoudi, Mehrdad; Antaki, James F.

    2016-01-01

    This study is motivated by the development of a blood cell filtration device for removal of malaria-infected, parasitized red blood cells (pRBCs). The blood was modeled as a multi-component fluid using the computational fluid dynamics discrete element method (CFD-DEM), wherein plasma was treated as a Newtonian fluid and the red blood cells (RBCs) were modeled as soft-sphere solid particles which move under the influence of drag, collisions with other RBCs, and a magnetic force. The CFD-DEM model was first validated by a comparison with experimental data from Han et al. 2006 (Han and Frazier 2006) involving a microfluidic magnetophoretic separator for paramagnetic deoxygenated blood cells. The computational model was then applied to a parametric study of a parallel-plate separator having hematocrit of 40% with a 10% of the RBCs as pRBCs. Specifically, we investigated the hypothesis of introducing an upstream constriction to the channel to divert the magnetic cells within the near-wall layer where the magnetic force is greatest. Simulations compared the efficacy of various geometries upon the stratification efficiency of the pRBCs. For a channel with nominal height of 100 µm, the addition of an upstream constriction of 80% improved the proportion of pRBCs retained adjacent to the magnetic wall (separation efficiency) by almost 2 fold, from 26% to 49%. Further addition of a downstream diffuser reduced remixing, hence improved separation efficiency to 72%. The constriction introduced a greater pressure drop (from 17 to 495 Pa), which should be considered when scaling-up this design for a clinical-sized system. Overall, the advantages of this design include its ability to accommodate physiological hematocrit and high throughput – which is critical for clinical implementation as a blood-filtration system.

  11. [Anesthesiologists' knowledge about packed red blood cells transfusion in surgical patients].

    Science.gov (United States)

    Soares, Joyce Mendes; Queiroz, Athos Gabriel Vilela; Queiroz, Vaniely Kaliny Pinheiro de; Falbo, Ana Rodrigues; Silva, Marcelo Neves; Couceiro, Tania Cursino de Menezes; Lima, Luciana Cavalcanti

    2016-10-10

    Blood is an important resource in several lifesaving interventions, such as anemia correction and improvement of oxygen transport capacity. Despite advances, packed red blood cell (PRBC) transfusion still involves risks. The aim of this study was to describe the knowledge of anesthesiologists about the indications, adverse effects, and alternatives to red blood cell transfusion intraoperatively. Cross-sectional study using a questionnaire containing multiple choice questions and clinical cases related to relevant factors on the decision whether to perform PRBC transfusion, its adverse effects, hemoglobin triggers, preventive measures, and blood conservation strategies. The questionnaire was filled without the presence of the investigator. Likert scale was used and the average rank of responses was calculated. The Epi Info 7 software was used for data analysis. 79% of the institution's anesthesiologists answered the questionnaire; 100% identified the main adverse effects related to blood transfusion. When asked about the factors that influence the transfusion decision, hemoglobin level had the highest agreement (MR=4.46) followed by heart disease (MR=4.26); hematocrit (MR=4.34); age (RM=4.1) and microcirculation evaluation (MR=4.22). Respondents (82.3%) identified levels of Hb=6g.dL(-1) as a trigger to transfuse healthy patient. Regarding blood conservation strategies, hypervolemic hemodilution (MR=2.81) and decided by drugs (MR=2.95) were the least reported. We identify a good understanding of anesthesiologists about PRBC transfusion; however, there is a need for refresher courses on the subject. Copyright © 2016. Publicado por Elsevier Editora Ltda.

  12. Zoonotic Bartonella species in fleas and blood from red foxes in Australia.

    Science.gov (United States)

    Kaewmongkol, Gunn; Kaewmongkol, Sarawan; Fleming, Patricia A; Adams, Peter J; Ryan, Una; Irwin, Peter J; Fenwick, Stanley G

    2011-12-01

    Bartonella are arthropod-borne, fastidious, Gram-negative, and aerobic bacilli distributed by fleas, lice, sand flies, and, possibly, ticks. The zoonotic Bartonella species, Bartonella henselae and Bartonella clarridgeiae, which are the causes of cat scratch disease and endocarditis in humans, have been reported from cats, cat fleas, and humans in Australia. However, to date, there has been no report of B. henselae or B. clarridgeiae in Australian wild animals and their ectoparasites. B. henselae and B. clarridgeiae were detected in fleas (Ctenocephalides felis) from red foxes (Vulpes vulpes), an introduced pest animal species in Australia, and only B. clarridgeiae was detected in blood from one red fox. Phylogenetic analysis of the ribosomal intergenic spacer region revealed that the B. henselae detected in the current study were related to B. henselae strain Houston-1, a major pathogenic strain in humans in Australia, and confirmed the genetic distinctness of B. clarridgeiae. The identification and characterization of Bartonella species in red foxes in the Southwest of Western Australia suggests that red foxes may act as reservoirs of infection for animals and humans in this region.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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 frequencies of 24 blood group antigens in the Chinese Han population from Mainland China. The data can be helpful in creating a donor database for

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

    Science.gov (United States)

    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

  16. Computational investigation on the photoacoustics of malaria infected red blood cells.

    Directory of Open Access Journals (Sweden)

    Ratan K Saha

    Full Text Available 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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  19. Red Blood Cell Antigen Genotyping for Sickle Cell Disease, Thalassemia, and Other Transfusion Complications.

    Science.gov (United States)

    Fasano, Ross M; Chou, Stella T

    2016-10-01

    Since the discovery of the ABO blood group in the early 20th century, more than 300 blood group antigens have been categorized among 35 blood group systems. The molecular basis for most blood group antigens has been determined and demonstrates tremendous genetic diversity, particularly in the ABO and Rh systems. Several blood group genotyping assays have been developed, and 1 platform has been approved by the Food and Drug Administration as a "test of record," such that no phenotype confirmation with antisera is required. DNA-based red blood cell (RBC) phenotyping can overcome certain limitations of hemagglutination assays and is beneficial in many transfusion settings. Genotyping can be used to determine RBC antigen phenotypes in patients recently transfused or with interfering allo- or autoantibodies, to resolve discrepant serologic typing, and/or when typing antisera are not readily available. Molecular RBC antigen typing can facilitate complex antibody evaluations and guide RBC selection for patients with sickle cell disease (SCD), thalassemia, and autoimmune hemolytic anemia. High-resolution RH genotyping can identify variant RHD and RHCE in patients with SCD, which have been associated with alloimmunization. In the future, broader access to cost-efficient, high-resolution RBC genotyping technology for both patient and donor populations may be transformative for the field of transfusion medicine.

  20. Impact of autologous blood transfusion on the use of pack of red blood cells in coronary artery bypass grafting surgery

    Directory of Open Access Journals (Sweden)

    Leonardo Leiria de Moura da Silva

    2013-06-01

    Full Text Available OBJECTIVE: To evaluate the impact of Cell Saver autologous blood transfusion system (CS on the use of packed red blood cells (pRBC in coronary artery bypass grafting (CABG surgery. METHODS: We carried out a retrospective cross-sectional study in 87 patients undergoing primary elective CABG with miniaturized cardiopulmonary bypass (miniCPB, divided in two groups: 44 without-CS and 43 with-CS. We investigated the necessity of absolute use and the volume of packed red blood cells (pRBC in each group, as well as cardiovascular risk factors, presurgical variables and intraoperative surgical parameters. All data were collected from medical records and there was no randomization or intervention on group selection. Statistical analysis was performed with Student t-test, Mann-Whitney U-test and χ² test, with a 5% significance level. RESULTS: There were no significant differences between the two groups in terms of cardiovascular risk factors and pre and intraoperative variables. Evaluating the absolute use of pRBC during surgery, there was a statistically significant difference (P=0.00008 between the groups without-CS (21/44 cases; 47.7% and with-CS (4/43 cases; 9.3%. There was also a statistically significant difference (P=0.000117 in the volumes of pRBC between the groups without-CS (198.651258.65ml and with-CS (35.061125.67ml. On the other hand, in the early postoperative period (up to 24h there was no difference regarding either the absolute use or the volumes of pRBC between both studied groups. CONCLUSION: Autologous erythrocyte transfusion with CS use reduces the use of intraoperative homologous pRBC in coronary artery bypass grafting surgeries associated with miniCPB.

  1. Effects of clove (Caryophyllus aromaticus L.) on the labeling of blood constituents with technetium-99m and on the morphology of red blood cells

    Energy Technology Data Exchange (ETDEWEB)

    Paoli, Severo de; Giani, Tania Santos; Presta, Giuseppe Antonio; Brandao-Neto, Jose; Medeiros, Aldo da Cunha; Santos-Filho, Sebastiao David [Universidade Federal do Rio Grande do Norte, Natal, RN (Brazil). Programa de Pos-graduacao em Ciencias da Saude]. E-mail: severodepaoli@gmail.com; Pereira, Marcia Oliveira; Fonseca, Adenilson de Souza da [Universidade do Estado do Rio de Janeiro (UERJ), RJ (Brazil). Inst. de Biologia Roberto Alcantara Gomes. Dept. de Biofisica e Biometria; Bernardo-Filho, Mario [Instituto Nacional do Cancer (INCa), Rio de Janeiro, RJ (Brazil). Coordenadoria de Pesquisa Basica

    2007-09-15

    Clove (Caryophyllus aromaticus L.) has been used for clinical procedures. Blood constituents labeled with technetium-99m (99mTc) are used in nuclear medicine. The aim of this work was to evaluate the effects of clove extract on the labeling blood constituents with 99mTc and on the morphology of red blood cells. Blood samples were incubated with clove, stannous chloride and 99mTc. Plasma, blood cells, insoluble fractions of plasma and blood cells were separated. The radioactivity was counted and percentage of radioactivity (%ATI) to each blood fraction was calculated. The shape and morphometric parameter (perimeter/area ratio) were evaluated. Clove extract altered significantly (p<0.05) the %ATI of blood constituents and the shape of red blood cells without modifying the perimeter/area ratio. The results indicate that clove extract presents chemical compounds that interfere with the radiolabeling of blood constituents and alter the morphology of red blood cells by oxidative/chelating actions or interacting with the cellular membrane structure. (author)

  2. Prevention of pure red cell aplasia after major or bidirectional ABO blood group incompatible hematopoietic stem cell transplantation by pretransplant reduction of host anti-donor isoagglutinins

    OpenAIRE

    Stussi, G.; Halter, J; Bucheli, E; Valli, P V; Seebach, L; Gmür, J; Gratwohl, A; Passweg, J. R.; Seebach, J.D.

    2009-01-01

    BACKGROUND: Persistent anti-donor isoagglutinins after major ABO blood group incompatible hematopoietic stem cell transplantation may cause delayed red blood cell engraftment and post-transplant pure red cell aplasia. DESIGN AND METHODS: We investigated the effect of pretransplant anti-donor isoagglutinin reduction by in vivo absorption and/or plasmapheresis on the incidence of pure red cell aplasia and the time to red blood cell engraftment in 153 hematopoietic stem cell transplant recipient...

  3. Minimal volume regulation after shrinkage of red blood cells from five species of reptiles

    DEFF Research Database (Denmark)

    Kristensen, Karina; Berenbrink, Michael; Koldkjær, Pia

    2008-01-01

    Red blood cells (RBCs) from most vertebrates restore volume upon hypertonic shrinkage and the mechanisms underlying this regulatory volume increase (RVI) have been studied extensively in these cells. Despite the phylogenetically interesting position of reptiles, very little is known about their red...... cell function. The present study demonstrates that oxygenated RBCs in all major groups of reptiles exhibit no or a very reduced RVI upon ~ 25% calculated hyperosmotic shrinkage. Thus, RBCs from the snakes Crotalus durissus and Python regius, the turtle Trachemys scripta and the alligator Alligator...... was not characterized. It seems, therefore, that the RVI response based on NHE activation was lost among the early sauropsids that gave rise to modern reptiles and birds, while it was retained in mammals. An RVI response has then reappeared in birds, but based on activation of the NKCC. Alternatively, the absence...

  4. Shape reconstruction and height fluctuations of red blood cells using defocusing microscopy

    CERN Document Server

    Siman, L; Amaral, F T; Agero, U; Mesquita, O N

    2014-01-01

    In this paper the bright-field defocusing microscopy (DM) technique is presented. DM is able to obtain quantitative information of each plane/surface of pure phase objects, as live unlabeled cells, and its application to red blood cells (RBCs) is demonstrated. Based on contrast, simple methods to obtain thickness profile and three dimensional (3D) total reconstruction of RBCs are proposed and the actual height profiles of upper and lower surface-membranes (lipid bilayer$/$cytoskeleton) of discocyte and stomatocyte red cells are presented as examples. In addition, using the mean square contrast fluctuation and modeling the RBC membranes fluctuations spectra as dependent of a bending modulus $(\\kappa_c)$, a surface tension $(\\sigma)$ and a confining potential $(\\gamma)$ term, slowly varying quantities along the cell radius, a genetic algorithm (GA) is used and the radial height fluctuations of each surface-membrane are accessed, separately. The radial behaviors of $\\kappa_c$, $\\sigma$ and $\\gamma$ are also obta...

  5. 3-D refractive index tomograms and deformability of individual human red blood cells from cord blood of newborn infants and maternal blood

    CERN Document Server

    Park, HyunJoo; Kim, Kyoohyun; Lee, Sangyun; Kook, Songyi; Lee, Dongheon; Suh, In Bum; Nab, Sunghun; Park, YongKeun

    2015-01-01

    Red blood cells (RBCs) from the cord blood of newborn infants have distinctive functions for fetal and infant development. To systematically investigate the biophysical characteristics of individual cord RBCs in newborn infants, a comparative study was performed of RBCs from cord blood of newborn infants, and of adult RBCs from mothers or non-pregnant women, employing optical holographic micro-tomography. Optical measurements of 3-D refractive index distributions, and of dynamic membrane fluctuations of individual RBCs, enabled retrieval of 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 significant larger than those of RBCs from non-pregnant women, and cord RBCs have more flattened shapes than RBCs in adults. In addition, the Hb content in the cord RBCs of newborns was significantly greater. The Hb concentration in cord RBCs was higher than for non-pregnant women or maternal RBCs, but t...

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  7. Historical time trends in red blood cell usage in the Netherlands

    Directory of Open Access Journals (Sweden)

    van Hoeven LR

    2016-06-01

    Full Text Available Loan R van Hoeven,1,2 Maria MW Koopman,3 Hendrik Koffijberg,4 Kit CB Roes,1 Mart P Janssen1,2 1Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Utrecht, 2Transfusion Technology Assessment Department, Sanquin Research, 3Department of Transfusion Medicine, Sanquin Blood Bank, Amsterdam, 4Department of Health Technology and Services Research, MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, Enschede, the Netherlands Background: While the number of hospitalized patients in Dutch hospitals has increased since 1997, the demand for red blood cell units (RBCs has simultaneously decreased. This implies a dramatic change in transfusion practice toward fewer blood transfusions on average per patient.Objectives: In order to explain the RBC reduction, different patient groups (surgical, medical, obstetrical, and specific age groups were studied retrospectively in relation to RBC use. In addition, the use of combinations of RBCs, fresh frozen plasma, and platelets during a transfusion episode was examined for trends over time.Materials and methods: Data from the PROTON database, containing information on all transfusions in twelve Dutch hospitals in the period 1996–2005, including corresponding patient data (age, diagnosis, treatment, and hospitalizations and blood unit data (type, amount, and date were analyzed.Results: The proportion of RBCs used for surgical patients declined from 50% in 1996 to 40% in 2005, whereas medical use increased from 47% to 58% (the remaining 2%–3% went to obstetrical patients. Changes were more marked in the higher age groups. Also, a trend was observed toward the use of only one or two RBCs during a transfusion episode rather than three or more. Among surgical patients who received blood, the use of combinations of blood units, as compared to RBCs only, increased from 32% to 39%.Conclusion: The results suggest a more restrictive transfusion policy

  8. Pharmacodynamic model of interleukin-21 effects on red blood cells in cynomolgus monkeys

    DEFF Research Database (Denmark)

    Overgaard, Rune Viig; Karlsson, M.; Ingwersen, S.H.

    2007-01-01

    Interleukin-21 (IL-21) is a novel cytokine that is currently under clinical investigations as a potential anti-cancer agent. Like many other anti-cancer agents, including other interleukins, IL-21 is seen to produce a broad range of biological effects that may be related to both efficacy and safe...... that the structural model presented here can be used for other types of drug induced loss of red blood cells, whereas the mechanism for sampling related blood loss is relevant for investigations of anaemia in all pharmacological studies with smaller animals.......Interleukin-21 (IL-21) is a novel cytokine that is currently under clinical investigations as a potential anti-cancer agent. Like many other anti-cancer agents, including other interleukins, IL-21 is seen to produce a broad range of biological effects that may be related to both efficacy and safety...... of treatment. The present analysis investigates the observed pharmacodynamics effects on red blood cells following various treatment schedules of human IL-21 administrated to cynomolgus monkeys. These effects are described by a novel non-linear mixed-effects model that enabled separation of drug effects...

  9. Hemorheological alterations of red blood cells induced by non-thermal dielectric barrier discharge plasma

    Science.gov (United States)

    Kim, Jeongho; Kim, Jae Hyung; Chang, Boksoon; Choi, Eun Ha; Park, Hun-Kuk

    2016-11-01

    Atmospheric pressure non-thermal plasma has been introduced in various applications such as wound healing, sterilization of infected tissues, blood coagulation, delicate surgeries, and so on. The non-thermal plasma generates reactive oxygen species (ROS), including ozone. Various groups have reported that the produced ROS influence proliferation and differentiation of cells, as well as apoptosis and growth arrest of tumor cells. In this study, we investigated the effects of non-thermal plasma on rheological characteristics of red blood cells (RBC). We experimentally measured the extent of hemolysis, deformability, and aggregation of red blood cells (RBC) with respect to exposure times of non-thermal plasma. RBC morphology was also examined using field-emission scanning electron microscopy. The absorbance of hemoglobin released from the RBCs increased with increasing exposure time of the non-thermal plasma. Values of the elongation index and aggregation index were shown to decrease significantly with increasing plasma exposure times. Therefore, hemorheological properties of RBCs could be utilized to assess the performance of various non-thermal plasmas.

  10. Analysis of short RNAs in the malaria parasite and its red blood cell host.

    Science.gov (United States)

    Rathjen, Tina; Nicol, Clare; McConkey, Glenn; Dalmay, Tamas

    2006-10-01

    RNA interference (RNAi) is an RNA degradation process that involves short, double-stranded RNAs (dsRNA) as sequence specificity factors. The natural function of the RNAi machinery is to generate endogenous short double-stranded RNAs to regulate gene expression. It has been shown that treatment of Plasmodium falciparum, the etiologic agent of malaria, with dsRNA induces degradation of the corresponding microRNA (miRNA), yet typical RNAi-associated genes have not been identifiable in the parasite genome. To clarify this discrepancy we set out to clone short RNAs from P. falciparum-infected red blood cells and from purified parasites. We did not find any short RNA that was not a rRNA or tRNA fragment. Indeed, only known human miRNAs were isolated in parasite preparations indicating that very few if any short RNAs exist in P. falciparum. This suggests a different mechanism than classical RNAi in observations of dsRNA-mediated degradation. Of the human miRNAs identified, the human miRNA mir-451 accumulates at a very high level in both infected and healthy red blood cells. Interestingly, mir-451 was not detectable in a series of immortalised cell lines representing progenitor stages of all major blood lineages, suggesting that mir-451 may play a role in the differentiation of erythroid cells.

  11. Red blood cell lysate modulates the expression of extracellular matrix proteins in dermal fibroblasts.

    Science.gov (United States)

    Akbari, Amir; Li, Yunyuan; Kilani, Ruhangiz T; Ghahary, Aziz

    2012-11-01

    During the early stage of wound healing process, blood clots can be served as a temporary extracellular matrix (ECM) to let skin cell migration and proliferation. The red blood cells are generally thought as inert bystanders in the early and inflammatory phase of wound healing. Here, we provide evidence that red blood cells (RBC) also play an important role in modulation of key ECM components such as type-I collagen, α-smooth muscle actin, fibronectin, and matrix metalloproteinases (MMPs). In this study, we used western blot analysis and showed a significant increase in the level of MMP-1, 2, 3. Furthermore, we found that RBC lysate significantly down-regulates type-I collagen and α-smooth muscle actin while up-regulates fibronectin expression in dermal fibroblasts. To further explore the mechanism by which RBC lysate modulates MMP-1 expression, the effect of inhibitors for three MAPK signaling pathways on RBC inducing MMP-1 expression by dermal fibroblasts were tested. The result showed that the inhibitor of ERK1/2 could abrogate the stimulatory effect of RBC lysate on MMP-1 expression in dermal fibroblasts. Consistently, RBC treatment results in an increase of ERK1/2 phosphorylation in dermal fibroblast. In conclusion, these findings suggest that RBC lysate can modulate the expression of MMPs and key ECM components which are important in healing process.

  12. Calculation of Intracellular Pressure of Red Blood Cells at Jaundice According to Atomic Force Microscopy Data

    Directory of Open Access Journals (Sweden)

    Yu.S. Nagornov

    2016-03-01

    Full Text Available The present work is devoted to the analysis of three-dimensional data of atomic force microscopy for research of the morphology of red blood cells. In this paper we built a biomechanical model of the erythrocyte, which allowed calculating the intracellular pressure of erythrocyte based on data of atomic force microscopy. As a result, we obtained the dependence intracellular pressure on the morphology of red blood cell. We have proposed a method of estimating of intracellular pressure of erythrocytes based on numerical modeling and data of atomic force microscopy of erythrocytes scan, which involves a comparison of the experimental data with the results of numerical calculation. The method is applied to the data of atomic force microscopy of erythrocytes of experimental animals - dwarf domestic pigs with different degrees of obstructive jaundice and normal. It is shown that with increasing severity of the disease and the concentration of bilirubin in the blood there is an infringement erythrocyte membranes, by an average increasing their volume and intracellular pressure.

  13. Measuring cell surface area and deformability of individual human red blood cells over blood storage using quantitative phase imaging

    Science.gov (United States)

    Park, Hyunjoo; Lee, Sangyun; Ji, Misuk; Kim, Kyoohyun; Son, Yonghak; Jang, Seongsoo; Park, Yongkeun

    2016-10-01

    The functionality and viability of stored human red blood cells (RBCs) is an important clinical issue in transfusions. To systematically investigate changes in stored whole blood, the hematological properties of individual RBCs were quantified in blood samples stored for various periods with and without a preservation solution called citrate phosphate dextrose adenine-1 (CPDA-1). With 3-D quantitative phase imaging techniques, the optical measurements for 3-D refractive index (RI) distributions and membrane fluctuations were done at the individual cell level. From the optical measurements, the morphological (volume, surface area and sphericity), biochemical (hemoglobin content and concentration), and mechanical parameters (dynamic membrane fluctuation) were simultaneously quantified to investigate the functionalities and progressive alterations of stored RBCs. Our results show that stored RBCs without CPDA-1 had a dramatic morphological transformation from discocytes to spherocytes within two weeks which was accompanied by significant decreases in cell deformability and cell surface area, and increases in sphericity. However, the stored RBCs with CPDA-1 maintained their morphology and deformability for up to 6 weeks.

  14. Red blood cell components: time to revisit the sources of variability.

    Science.gov (United States)

    Sparrow, Rosemary L

    2017-03-01

    Quality and safety of red blood cell (RBC) components is managed by screening of donors and strict regulatory controls of blood collection, processing and storage procedures. Despite these efforts, variations in RBC component quality exist as exemplified by the wide range in storage-induced haemolysis. This article provides a brief overview of the variables that contribute or potentially contribute to the quality of stored RBC components, including blood collection, processing, and donor-related variables. Particular focus is made on donor health and lifestyle factors that are not specifically screened and may impact on the physicobiochemical properties of RBCs and their storability. Inflammatory and oxidative stress states may be especially relevant as RBCs are susceptible to oxidative injury. Few studies have investigated the effect of specific donor-related variables on the quality of stored RBC components. Donor-related variables may be unaccounted confounders in the "age of blood" clinical studies that compared outcomes following transfusion of fresher or longer-stored RBC components. The conclusion is drawn that the blood donor is the greatest source of RBC component variability and the least "regulated" aspect of blood component production. It is proposed that more research is needed to better understand the connection between donor-related variables and quality consistency of stored RBC components. This could be very important given the impact of modern lifestyles that sees escalating rates of non-communicable health conditions that are associated with increased oxidative stress, such as hypertension, obesity and diabetes in children and adults, as well as an ageing population in many countries. The effect of these changes to global health and population demographics will impact on blood donor panels, and without significant new research, the consequences on the quality of stored blood components and transfusion outcomes are unknown.

  15. Urgent replacement of a mechanical mitral prosthesis in an anticoagulated patient with Bombay red blood cell phenotype.

    Science.gov (United States)

    Nairn, Travis K; Giulivi, Antonio; Neurath, Doris; Tokessy, Melanie; Sia, Ying T; Ruel, Marc; Wilkes, Peter R H

    2010-06-01

    Bombay red blood cell phenotype is an extremely rare blood type for which patients can receive only autologous or Bombay phenotype red blood cells. We report a case of urgent repeat sternotomy for replacement of a mechanical mitral prosthesis in a patient with Bombay phenotype anticoagulated with warfarin, to emphasize the transfusion challenges in such patients. A male of Indian descent presented to hospital with New York Heart Association IV symptoms. His medical history revealed previous mitral valve replacement with a mechanical prosthesis in 2005 and Bombay phenotype blood. Preoperative transthoracic echocardiography demonstrated thrombus obstruction of the mitral prosthesis despite anticoagulation with warfarin. Right ventricular systolic pressure was >100 mmHg with 3+ tricuspid regurgitation. The patient's condition was temporized with diuretics, bronchodilators, and bi-level positive airway pressure ventilation while transfusion medicine and cardiac surgery were consulted for urgent surgery. The patient received vitamin K and prothrombin complex concentrate prior to repeat sternotomy and successful mitral prosthesis replacement. After cardiopulmonary bypass, heparinization was corrected with protamine and followed by a second dose of prothrombin complex concentrate and recombinant activated factor VIIa. Postoperatively, the patient received four units of packed red blood cells, two autologous units and two units of Bombay specific red blood cells. Right ventricular pressures stabilized at 40 mmHg following surgery. The patient recovered following several days of inotropic support with milrinone, diuretics, and bronchodilators. Patients with Bombay phenotype red blood cells present as type O, but they are unable to receive red blood cells from any phenotype other than Bombay phenotype. They are able to receive all other blood products, including fresh frozen plasma, cryoprecipitate, platelets, prothrombin complex concentrate, and recombinant activated factor

  16. Levels of carnitine and acylcarnitines in reconstituted red blood cell samples washed with different concentrations of saline solutions

    Directory of Open Access Journals (Sweden)

    José Henry Osorio

    2011-01-01

    Full Text Available Objective: To evaluate the percentage of carnitine and acylcarnitines remaining in red blood cells after washing them with different concentrations of saline solution. Materials and methods: Human blood samples were centrifuged and the blood cells were washed with different saline solutions. The final pellet was resuspended in PBS for card preparation and tandem mass spectrometry analysis. Results: It was found that carnitine, as well as short-chain, medium-chain, and long-chain acylcarnitines remain in red blood cells at average percentages of 19.3; 34; 34; and 32%, respectively. Significant differences were found for carnitine and acylcarnitine levels in blood washed with an isotonic solution compared to their levels using several hypotonic solutions (p<0.05. Conclusion: Because carnitine and acylcarnitines remained associated with the blood cells, we recommend using whole blood to measure these metabolites.

  17. Levels of carnitine and acylcarnitines in reconstituted red blood cell samples washed with different concentrations of saline solutions

    Directory of Open Access Journals (Sweden)

    José Henry Osorio

    2010-12-01

    Full Text Available Objective: To evaluate the percentage of carnitine and acylcarnitines remaining in red blood cells after washing them with different concentrations of saline solution.Materials and methods: Human blood samples were centrifuged and the blood cells were washed with different saline solutions. The final pellet was resuspended in PBS for card preparation and tandem mass spectrometry analysis.Results: It was found that carnitine, as well as short-chain, medium-chain, and long-chain acylcarnitines remain in red blood cells at average percentages of 19.3; 34; 34; and 32%, respectively. Significant differences were found for carnitine and acylcarnitine levels in blood washed with an isotonic solution compared to their levels using several hypotonic solutions (p<0.05.Conclusion: Because carnitine and acylcarnitines remained associated with the blood cells, we recommend using whole blood to measure these metabolites.

  18. Korean Red Ginseng Improves Blood Pressure Stability in Patients with Intradialytic Hypotension

    Directory of Open Access Journals (Sweden)

    I-Ju Chen

    2012-01-01

    Full Text Available Introduction. Intradialytic hypotension (IDH is a common complication during hemodialysis which may increase mortality risks. Low dose of Korean red ginseng (KRG has been reported to increase blood pressure. Whether KRG can improve hemodynamic stability during hemodialysis has not been examined. Methods. The 8-week study consisted of two phases: observation phase and active treatment phase. According to prehemodialysis blood pressure (BP, 38 patients with IDH were divided into group A (BP ≥ 140/90 mmHg, n = 18 and group B (BP < 140/90 mmHg, n = 20. Patients were instructed to chew 3.5 gm KRG slices at each hemodialysis session during the 4-week treatment phase. Blood pressure changes, number of sessions disturbed by symptomatic IDH, plasma levels of vasoconstrictors, blood biochemistry, and adverse effects were recorded. Results. KRG significantly reduced the degree of blood pressure drop during hemodialysis (P<0.05 and the frequency of symptomatic IDH (P<0.05. More activation of vasoconstrictors (endothelin-1 and angiotensin II during hemodialysis was found. The postdialytic levels of endothelin-1 and angiotensin II increased significantly (P<0.01. Conclusion. Chewing KRG renders IDH patients better resistance to acute BP reduction during hemodialysis via activation of vasoconstrictors. Our results suggest that KRG could be an adjuvant treatment for IDH.

  19. Inhibition of pseudoperoxiadse activity of human red blood cell hemoglobin by methocarbamol.

    Science.gov (United States)

    Minai-Tehrani, Dariush; Toofani, Sara; Yazdi, Fatemeh; Minai-Tehrani, Arash; Mollasalehi, Hamidreza; Bakhtiari Ziabari, Kourosh

    2017-01-01

    After red blood cells lysis, hemoglobin is released to blood circulation. Hemoglobin is carried in blood by binding to haptoglobin. In normal individuals, no free hemoglobin is observed in the blood, because most of the hemoglobin is in the form of haptoglobin complex. In some diseases that are accompanied by hemolysis, the amount of released hemoglobin is higher than its complementary haptoglobin. As a result, free hemoglobin appears in the blood, which is a toxic compound for these patients and may cause renal failure, hypertensive response and risk of atherogenesis. Free hemoglobin has been determined to have peroxidase activity and considered a pseudoenzyme. In this study, the effect of methocarbamol on the peroxidase activity of human hemoglobin was investigated. Our results showed that the drug inhibited the pseudoenzyme by un-competitive inhibition. Both Km and Vmax decreased by increasing the drug concentration. Ki and IC50 values were determined as 6 and 10mM, respectively. Docking results demonstrated that methocarbamol did not attach to heme group directly. A hydrogen bond linked NH2 of carbamate group of methocarbamol to the carboxyl group of Asp126 side chain. Two other hydrogen bonds could be also observed between hydroxyl group of the drug and Ser102 and Ser133 residues of the pseudoenzyme.

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

    Science.gov (United States)

    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.

  1. Rheology of red blood cells in patients with HbC disease.

    Science.gov (United States)

    Lemonne, Nathalie; Billaud, Marie; Waltz, Xavier; Romana, Marc; Hierso, Régine; Etienne-Julan, Maryse; Connes, Philippe

    2016-01-01

    Patients with hemoglobin C disease (CC) usually do not develop severe complications in comparison with individuals with sickle cell anemia (SS) or with sickle cell hemoglobin C disease (SC). The present study compared the hematological, biochemical, hemorheological and clinical characteristics of CC patients to those of SS, SC and healthy individuals (AA). Blood viscosity was measured at 225 s(-1) with a cone plate viscometer. The hematocrit-to-blood viscosity ratio (HVR), i.e. an index of red blood cell (RBC) oxygen transport effectiveness, was calculated. RBC deformability was determined at 30 Pa by ektacytometry, and RBC aggregation properties by syllectometry. CC and SC had higher blood viscosity and lower HVR than AA. Nevertheless, HVR was higher in CC compared to SS and tended to be higher than in SC. The CC group exhibited very rigid hyperchromic RBC compared to the three other groups. RBC aggregation abnormalities were observed in CC: low RBC aggregation index and high RBC aggregates strength. Despite these hemorheological abnormalities, CC never had hospitalized painful vaso-occlusive crisis or acute chest syndrome. In contrast, all of them had splenomegaly. Of note, 2 out of 7 CC developed retinopathy or otologic disorders. Whether the blood hyperviscosity and decreased RBC deformability are responsible for these complications is unknown. The higher oxygen transport effectiveness (i.e., HVR) of CC compared to SS is probably at the origin of the very low risk of medical complication in this population.

  2. Association of nucleated red blood cells with mortality in critically ill dogs.

    Science.gov (United States)

    Müller, M; Dörfelt, R; Hamacher, L; Wess, G

    2014-11-22

    The occurrence of nucleated red blood cells (NRBC) in the peripheral blood of critically ill human patients is associated with increased mortality. In dogs, the presence of NRBCs in peripheral blood has been used as a sensitive and specific marker of complications and outcome associated with heatstroke. However, no study has investigated their prevalence in critically ill dogs. Thus, the aim of this study was to determine the prevalence of NRBCs in the peripheral blood, and to evaluate their occurrence as a prognostic factor in critically ill dogs. One hundred and one dogs were prospectively included; the presence of NRBCs was studied on a daily basis from the time of admission until day 3 in the intensive care unit (or less if discharged or death occurred earlier). Dogs fulfilled at least two systemic inflammatory response syndrome (SIRS) criteria and suffered from various diseases. Survival was defined as being alive 28 days postdischarge from hospital. In 42 dogs, NRBCs were detected at least once; 59 patients were NRBC negative. Mortality was significantly higher in NRBC-positive than NRBC-negative patients (54.8 v 30.5 per cent) (P=0.014). However, this association was not present when anaemic dogs were excluded from the analysis. Detection of NRBCs in the peripheral blood may be an indicator for regenerative anaemia and may have potential for use as a prognostic tool or in addition to established scoring systems in critically ill dogs.

  3. Instant Effects of Radiofrequency Electromagnetic Wave on Hemoglobin in Single Living Intact Red Blood Cell

    Institute of Scientific and Technical Information of China (English)

    Cheng Can YAO; Xiao Kun LI; Yao Xiong HUANG

    2005-01-01

    The absorption spectrum of the hemoglobin (Hb) in single living intact red blood cell (RBC), exposed in 900 MHz radiofrequency electromagnetic wave (RF-EMW), was non-invasive,in situ, real-time measured by employing a highly sensitive fast multi-channel microspectrophotometer system. Both the absorption intensity and site of intracellular Hb were altered after RBCs were exposed in 900 MHz RF-EMW with power density at 5 mW/cm2. It was indicated that not only the concentration of Hb in living RBCs was decreased, but the molecular structure of Hb was changed by the RF-EMW action.

  4. Autistic children exhibit decreased levels of essential Fatty acids in red blood cells.

    Science.gov (United States)

    Brigandi, Sarah A; Shao, Hong; Qian, Steven Y; Shen, Yiping; Wu, Bai-Lin; Kang, Jing X

    2015-05-04

    Omega-6 (n-6) and omega-3 (n-3) polyunsaturated fatty acids (PUFA) are essential nutrients for brain development and function. However, whether or not the levels of these fatty acids are altered in individuals with autism remains debatable. In this study, we compared the fatty acid contents between 121 autistic patients and 110 non-autistic, non-developmentally delayed controls, aged 3-17. Analysis of the fatty acid composition of red blood cell (RBC) membrane phospholipids showed that the percentage of total PUFA was lower in autistic patients than in controls; levels of n-6 arachidonic acid (AA) and n-3 docosahexaenoic acid (DHA) were particularly decreased (pautism.

  5. Flavonoid oligomers from Chinese dragon’s blood, the red resins of Dracaena cochinchinensis

    OpenAIRE

    Zheng, Qing-An; Xu, Min; Yang, Chong-Ren; Dong WANG; Li, Hai-Zhou; Zhu, Hong-Tao; Zhang, Ying-Jun

    2012-01-01

    A detailed chemical investigation of the red resins from Dracaena cochinchinensis (Chinese dragon’s blood) yielded five new flavonoid oligomers, named cochinchinenins D-H (1–5), together with a known biflavonoid, cinnabarone (6), and a mixture of two known biflavonoids, socotrin-4′-ol (7) and homoisosocotrin-4′-ol (8). Of these new compounds, 1–3 were biflavonoids and 4 and 5 were triflavonoids. Their structures were determined on the basis of spectroscopic analysis. The isolated compounds we...

  6. Nonlinear chemical imaging microscopy: near-field third harmonic generation imaging of human red blood cells.

    Science.gov (United States)

    Schaller, R D; Johnson, J C; Saykally, R J

    2000-11-01

    Third harmonic generation (THG) imaging using a near-field scanning optical microscope (NSOM) is demonstrated for the first time. A femtosecond, tunable near-infrared laser was used to generate both nonresonant and resonantly enhanced third harmonic radiation in human red blood cells. We show that resonantly enhanced THG is a chemically specific bulk probe in NSOM imaging by tuning the excitation source onto and off of resonance with the Soret transition of oxyhemoglobin. Additionally, we provide evidence that tightly focused, nonresonant, far-field THG imaging experiments do not produce contrast that is truly surface specific.

  7. Lift and down-gradient shear-induced diffusion in Red Blood Cell suspensions

    CERN Document Server

    Grandchamp, Xavier; Srivastav, Aparna; Minetti, Christophe; Podgorski, Thomas

    2013-01-01

    The distribution of Red Blood Cells in a confined channel flow is inhomogeneous and shows a marked depletion near the walls due to a competition between migration away from the walls and shear-induced diffusion resulting from interactions between particles. We investigated the lift of RBCs in a shear flow near a wall and measured a significant lift velocity despite the tumbling motion of cells. We also provide values for the collective and anisotropic shear-induced diffusion of a cloud of RBCs, both in the direction of shear and in the direction of vorticity. A generic down-gradient subdiffusion characterized by an exponent 1/3 is highlighted.

  8. The effect of some medical treatments of thalassemia on the red blood cells

    Science.gov (United States)

    Zhang, Xiufang; Shen, Linming; Bao, Hongxia; Din, Xiaolan; Wang, Rongxin; Liu, Yuanyuan; Gao, Naifei; Huang, Youwen

    1992-04-01

    The Mössbauer spectroscopy (MS) and circular dichroism (CD) measurements have been used to investigate the effect of some medical treatments on the red blood cells (RBCs) of the patients with HbH discase and β-thalassemia (Thal.) major, respectively. The results indicate that both splenectomy and treatment with myleran are effective to alleviate the symptoms of anemia for some patients, but both of them are different in the effect on the RBCs of the patients. On the basis of the results, a hypothesis on the course of denaturation in hemoglobin (Hb) of the patients is proposed.

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

    Science.gov (United States)

    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

  10. Optimal Fluxes, Reaction Replaceability, and Response to Enzymopathies in the Human Red Blood Cell

    Directory of Open Access Journals (Sweden)

    A. De Martino

    2010-01-01

    most harmful reaction knockouts. The integration of combinatorial methods with sampling techniques to explore the space of viable flux states may provide crucial insights on this issue. We assess the replaceability of every metabolic conversion in the human red blood cell by enumerating the alternative paths from substrate to product, obtaining a complete map of he potential damage of single enzymopathies. Sampling the space of optimal steady state fluxes in the healthy and in the mutated cell reveals both correlations and complementarity between topologic and dynamical aspects.

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

    CERN Document Server

    Park, HyunJoo; Kim, Kyoohyun; Cho, Shin-Hyeong; Lee, Won-Ja; Kim, Youngchan; Lee, SangEun; 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.

  12. Force balance and membrane shedding at the Red Blood Cell surface

    OpenAIRE

    Sens, Pierre; Gov, Nir

    2006-01-01

    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 nano-vesicles. 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 qu...

  13. Small molecule ice recrystallization inhibitors mitigate red blood cell lysis during freezing, transient warming and thawing

    Science.gov (United States)

    Briard, Jennie G.; Poisson, Jessica S.; Turner, Tracey R.; Capicciotti, Chantelle J.; Acker, Jason P.; Ben, Robert N.

    2016-03-01

    During cryopreservation, ice recrystallization is a major cause of cellular damage. Conventional cryoprotectants such as dimethyl sulfoxide (DMSO) and glycerol function by a number of different mechanisms but do not mitigate or control ice recrystallization at concentrations utilized in cryopreservation procedures. In North America, cryopreservation of human red blood cells (RBCs) utilizes high concentrations of glycerol. RBC units frozen under these conditions must be subjected to a time-consuming deglycerolization process after thawing in order to remove the glycerol to increased post-thaw recovery of RBCs. The most potent IRI from this study is also capable of protecting frozen RBCs against the large temperature fluctuations associated with transient warming.

  14. Tank-treading and tumbling frequencies of capsules and red blood cells.

    Science.gov (United States)

    Yazdani, Alireza Z K; Kalluri, R Murthy; Bagchi, Prosenjit

    2011-04-01

    This study is motivated in part by the discrepancy that exists in the literature with regard to the dependence of the tank-treading frequency of red blood cells on the shear rate and suspending medium viscosity. Here we consider three-dimensional numerical simulations of deformable capsules of initially spherical and oblate spheroidal shapes and biconcave discoid representing the red blood cell resting shape. By considering a much broader range of the viscosity ratio (ratio of capsule or cell interior to suspending fluid viscosity), shear rate, and aspect ratio (ratio of minor to major axes) than that considered in the previous experiments, we find several new characteristics of the tank-treading and tumbling frequencies that have not been reported earlier. These new characteristics are the result of the large shape deformation and the coupling between shape and angular oscillations of the capsules or cells. For the spherical and oblate spheroidal capsules, the tank-treading frequency shows a nonmonotonic trend that is characterized by an initial decrease leading to a minimum followed by an increase with increasing viscosity ratio. For red blood cells, we find two regimes of the viscosity dependence of the tank-treading frequency: an exponential regime in which the tank-treading frequency decreases at a slower rate with increasing viscosity ratio, and a logarithmic range in which it decreases at a much faster rate. While this trend agrees well with different theoretical models of shape-preserving capsules, it was not evident in previous experimental results. When the shear rate dependence is considered, the tank-treading frequency of red blood cells and capsules of highly elongated initial shapes exhibits a nonmonotonic trend that is characterized by an initial increase leading to a maximum followed by a sharp decrease with decreasing shear rate. This anomalous behavior of the tank-treading frequency is shown to be due to a breathing-like dynamics of the capsule or

  15. The Quality Assessment of Stored Red Blood Cells Probed Using Atomic-Force Microscopy

    OpenAIRE

    Lamzin, I. M.; Khayrullin, R. M.

    2014-01-01

    At the moment the suitability of stored red blood cells (sRBC) for transfusion is checked by routine methods such as haemoglobin estimation and the level of haemolysis. These methods cannot characterize directly the quality of the membranes of sRBC. The aim of this work is to assess the quality of sRBC based on such criteria as the membrane’s stiffness and the size and the form of sRBC. Materials and Methods. We have investigated 5 series of dry cytosmears of the sRBC which had been kept in b...

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

    Science.gov (United States)

    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.

  17. On the complex dynamics of a red blood cell in simple shear flow

    CERN Document Server

    Vlahovska, Petia M; Danker, Gerrit; Misbah, Chaouqi

    2010-01-01

    Motivated by the reported peculiar dynamics of a red blood cell in shear flow, we develop an analytical theory for the motion of a nearly--spherical fluid particle enclosed by a visco--elastic incompressible interface in linear flows. The analysis explains the effect of particle deformability on the transition from tumbling to swinging as the shear rate increases. Near the transition, intermittent behavior is predicted only if the particle has a fixed shape; the intermittency disappears for a deformable particle. Comparison with available phenomenological models based on the fixed shape assumption highlights their physical foundations and limitations.

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

    Science.gov (United States)

    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

  19. Current topics in red cell biology: report on the Red Cell Special Interest Group meeting held at NHS Blood and Transplant Bristol on 30 October 2015.

    Science.gov (United States)

    Bullock, T; Bruce, L J; Ridgwell, K

    2016-08-01

    The Red Cell Special Interest Group (SIG) meeting, hosted by the British Blood Transfusion Society, provides an annual forum for the presentation of UK- and European-based red cell research. The 2015 meeting was held on Friday 30 October at the National Health Service Blood & Transplant (NHSBT) facility in Filton, Bristol and provided an exciting and varied programme on the themes of erythropoiesis, malaria biology and pathophysiology and red cells properties in stress and disease. Ten speakers presented on these topics over the course of one day. The meeting was well attended by over 90 delegates. Posters were presented during the lunch break, and abstracts from the posters are published at the end of this issue.

  20. Elevated red blood cell 2,3-diphosphoglycerate levels in black blood donors.

    Science.gov (United States)

    Wallas, C H

    1978-01-01

    Mean levels of 2,3-diphosphoglycerate (DPG) were significantly increased in erythrocytes (RBC) from 43 nonanemic black blood donors (4.80 +/- 0.06 micromoles/l RBC) compared with 22 white donors 4.47 +/- 0.08 micromoles/l RBCs from eight of the 12 black donors with DPG levels greater than 5 micromoles/l RBC. Although a potentially hemolytic disorder could be defined in four (AS hemoglobin, beta-Thalassemia minor, G6PD deficiency), reticulocyte counts were normal. However, when RBCs from the subgroup were compared to RBCs from an additional 25 unselected white donors, the following suggested an abnormally large population of young RBCs in the subgroup: 1) normal or elevated RBC-ATP with normal serum phosphate level; 2) significantly increased activities of RBC age-dependent enzymes hexokinase (p less than 0.02), pyruvate kinase (p less than 0.05), and glutamicoxaloacetic transaminase (p less than 0.01), with normal activity of phosphoglycerate kinase, an age-independent enzyme; 3) decreased dense (older) RBCs as determined by sedimentation in phthalate esters. Since DPG is increased in young RBCs and falls as the RBC ages, loss of older relatively DPG depleted RBCs due to shortened survival could account for the elevated DPG levels seen in the subgroup.

  1. Uranium determination in the red blood cells of workers engaged in the chemical treatment of uranium ore

    Energy Technology Data Exchange (ETDEWEB)

    Nosek, J.; Simkova, M.; Kukula, F.; Musil, K.

    1973-10-01

    Using the neutron activation analysis method, the uranium levels were determined in red blood cells of venous blood samples from persons occupationally exposed to this metal in chemical processing plants using wet methods (6.5+-2.1ppb U) or dry methods (37.2+-20.2ppb U), and of controls (4.1+-2.6ppb U).

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

    Science.gov (United States)

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

    2016-04-01

    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.

  3. Structural damage of chicken red blood cells exposed to platinum nanoparticles and cisplatin

    DEFF Research Database (Denmark)

    Kutwin, Marta; Sawosz, Ewa; Jaworski, Sławomir;

    2014-01-01

    of platinum nanoparticles (NP-Pt) and cisplatin with blood compartments are important for future applications. This study investigated structural damage, cell membrane deformation and haemolysis of chicken embryo red blood cells (RBC) after treatment with cisplatin and NP-Pt. Cisplatin (4 μg/ml) and NP-Pt (2......Side effects and resistance of cancer cells to cisplatin are major drawbacks to its application, and recently, the possibility of replacing cisplatin with nanocompounds has been considered. Most chemotherapeutic agents are administered intravenously, and comparisons between the interactions......,6 μg/ml), when incubated with chicken embryo RBC, were detrimental to cell structure and induced haemolysis. The level of haemolytic injury was increased after cisplatin and NP-Pt treatments compared to the control group. Treatment with cisplatin caused structural damage to cell membranes...

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

    Science.gov (United States)

    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

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

    Directory of Open Access Journals (Sweden)

    Kizzy-Clara Cita

    Full Text Available To investigate the association between priapism in men with sickle cell anemia (SCA and hemorheological and hemolytical parameters.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.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.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.

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

    Science.gov (United States)

    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.

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

    Directory of Open Access Journals (Sweden)

    Hongbin Tu

    2015-11-01

    Full Text Available 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.

  8. Computational analysis on the mechanical interaction between a thrombus and red blood cells: possible causes of membrane damage of red blood cells at microvessels.

    Science.gov (United States)

    Kamada, Hiroki; Imai, Yohsuke; Nakamura, Masanori; Ishikawa, Takuji; Yamaguchi, Takami

    2012-12-01

    Previous studies investigating thrombus formation have not focused on the physical interaction between red blood cells (RBCs) and thrombus, although they have been speculated that some pathological conditions such as microangiopathic hemolytic anemia (MAHA) stem from interactions between RBCs and thrombi. In this study, we investigated the mechanical influence of RBCs on primary thrombi during hemostasis. We also explored the mechanics and aggravating factors of intravascular hemolysis. Computer simulations of primary thrombogenesis in the presence and the absence of RBCs demonstrated that RBCs are unlikely to affect the thrombus height and coverage, although their presence may change microvessel hemodynamics and platelet transportation to the injured wall. Our results suggest that intravascular hemolysis owing to RBC membrane damage would be promoted by three hemodynamic factors: (1) dispersibility of platelet thrombi, because more frequent spatial thrombus formation decreases the time available for an RBC to recover its shape and enforces more severe deformation; (2) platelet thrombus stiffness, because a stiffer thrombus increases the degree of RBC deformation upon collision; and (3) vessel size and hemocyte density, because a smaller vessel diameter and higher hemocyte density decrease the room for RBCs to escape as they come closer to a thrombus, thereby enhancing thrombus-RBC interactions.

  9. 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

    Science.gov (United States)

    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.

  10. From artificial red blood cells, oxygen carriers, and oxygen therapeutics to artificial cells, nanomedicine, and beyond.

    Science.gov (United States)

    Chang, Thomas M S

    2012-06-01

    The first experimental artificial red blood cells have all three major functions of red blood cells (rbc). However, the first practical one is a simple polyhemoglobin (PolyHb) that only has an oxygen-carrying function. This is now in routine clinical use in South Africa and Russia. An oxygen carrier with antioxidant functions, PolyHb-catalase-superoxide dismutase, can fulfill two of the three functions of rbc. Even more complete is one with all three functions of rbc in the form of PolyHb-catalase-superoxide dismutase-carbonic anhydrase. The most advanced ones are nanodimension artificial rbc with either PEG-lipid membrane or PEG-PLA polymer membrane. Extensions into oxygen therapeutics include a PolyHb-tyrosinase that suppresses the growth of melanoma in a mice model. Another is a PolyHb-fibrinogen that is an oxygen carrier with platelet-like function. Research has now extended well beyond the original research on artificial rbc into many areas of artificial cells. These include nanoparticles, nanotubules, lipid vesicles, liposomes, polymer-tethered lipid vesicles, polymersomes, microcapsules, bioencapsulation, nanocapules, macroencapsulation, synthetic cells, and others. These are being used in nanotechnology, nanomedicine, regenerative medicine, enzyme/gene therapy, cell/stem cell therapy, biotechnology, drug delivery, hemoperfusion, nanosensers, and even by some groups in agriculture, industry, aquatic culture, nanocomputers, and nanorobotics.

  11. Neonatal nucleated red blood cells in infants of overweight and obese mothers.

    Science.gov (United States)

    Sheffer-Mimouni, Galit; Mimouni, Francis B; Dollberg, Shaul; Mandel, Dror; Deutsch, Varda; Littner, Yoav

    2007-06-01

    The perinatal outcome of the infant of obese mother is adversely affected and in theory, may involve fetal hypoxia. We hypothesized that an index of fetal hypoxia, the neonatal nucleated red blood cell (NRBC) count, is elevated in infants of overweight and obese mothers. Absolute NRBC counts taken during the first 12 hours of life in 41 infants of overweight and obese mothers were compared to 28 controls. Maternal body mass index and infant birthweight were significantly higher in the overweight and obese group (P cell and lymphocyte counts did not differ between groups. The absolute NRBC count was higher (P = 0.01), and the platelet count lower (P = 0.05) in infants of overweight and obese mothers than in controls. In stepwise regression analysis, the absolute NRBC count in infants of overweight and obese mothers remained significantly higher even after taking into account birthweight or gestational age and Apgar scores (P mothers have increased nucleated red blood cells at birth compared with controls. We speculate that even apparently healthy fetuses of overweight and obese mothers are exposed to a subtle hypoxemic environment.

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

    Science.gov (United States)

    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.

  13. Prophylactic Plasma Transfusion Is Not Associated With Decreased Red Blood Cell Requirements in Critically Ill Patients.

    Science.gov (United States)

    Warner, Matthew A; Chandran, Arun; Jenkins, Gregory; Kor, Daryl J

    2017-05-01

    Critically ill patients frequently receive plasma transfusion under the assumptions that abnormal coagulation test results confer increased risk of bleeding and that plasma transfusion will decrease this risk. However, the effect of prophylactic plasma transfusion remains poorly understood. The objective of this study was to determine the relationship between prophylactic plasma transfusion and bleeding complications in critically ill patients. This is a retrospective cohort study of adults admitted to the intensive care unit (ICU) at a single academic institution between January 1, 2009 and December 31, 2013. Inclusion criteria included age ≥18 years and an international normalized ratio measured during ICU admission. Multivariable propensity-matched analyses were used to evaluate associations between prophylactic plasma transfusion and outcomes of interest with a primary outcome of red blood cell transfusion in the ensuing 24 hours and secondary outcomes of hospital- and ICU-free days and mortality within 30 days of ICU discharge. A total of 27,561 patients were included in the investigation with 2472 (9.0%) receiving plasma therapy and 1105 (44.7%) for which plasma transfusion was prophylactic in nature. In multivariable propensity-matched analyses, patients receiving plasma had higher rates of red blood cell transfusion (odds ratio: 4.3 [95% confidence interval: 3.3-5.7], P plasma in the critically ill was not associated with improved clinical outcomes. Further investigation examining the utility of plasma transfusion in this population is warranted.

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

    Energy Technology Data Exchange (ETDEWEB)

    Gourley, P.L.; Meissner, K.E.; Brennan, T.M.; Hammons, B.E. [Sandia National Labs., Albuquerque, NM (United States); Gourley, M.F. [National Institutes of Health, Bethesda, MD (United States)

    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.

  15. Mechanical interactions between ice crystals and red blood cells during directional solidification.

    Science.gov (United States)

    Ishiguro, H; Rubinsky, B

    1994-10-01

    Experiments in which red blood cells were frozen on a directional solidification stage under a microscope show that there is a mechanical interaction between ice crystals and cells in which cells are pushed and deformed by the ice crystals. The mechanical interaction occurs during freezing of cells in physiological saline and is significantly inhibited by the addition of 20% v/v glycerol to the solution. The addition of osmotically insignificant quantities of antifreeze proteins from the winter flounder or ocean pout to the physiological saline with 20% v/v glycerol generates strong mechanical interactions between the ice and the cells. The cells were destroyed during freezing in physiological saline, survived freezing in physiological saline with glycerol, and were completely destroyed by the addition of antifreeze proteins to the solution with glycerol. The difference in cell survival through freezing and thawing appears to be related, in part, to the habit of ice crystal growing in the suspension of red blood cells and the nature of mechanical interaction between the ice crystal and the cells. This suggests that mechanical damage may be a factor during cryopreservation of cells.

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

    Science.gov (United States)

    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.

  17. Macromolecular depletion modulates the binding of red blood cells to activated endothelial cells.

    Science.gov (United States)

    Yang, Yang; Koo, Stephanie; Lin, Cheryl Shuyi; Neu, Björn

    2010-09-01

    Adhesion of red blood cells (RBCs) to endothelial cells (ECs) is usually insignificant but an enhanced adhesion has been observed in various diseases associated with vascular complications. This abnormal adhesion under pathological conditions such as sickle cell disease has been correlated with increased levels of various plasma proteins but the detailed underlying mechanism(s) remains unclear. Usually it is assumed that the proadhesive effects of plasma proteins originate from ligand interactions cross-linking receptors on adjacent cells, but explicit results detailing binding sites or receptors for some proteins (e.g., fibrinogen) on either RBC or EC surfaces that would support this model are missing. In this study, the authors tested whether there is an alternative mechanism. Their results demonstrate that dextran 2 MDa promotes the adhesion of normal RBCs to thrombin-activated ECs and that this effect becomes more pronounced with increasing thrombin concentration or with prolonged thrombin incubation time. It is concluded that depletion interaction originating from nonadsorbing macromolecules (i.e., dextran) can modulate the adhesion of red blood cells to thrombin-activated EC. This study thereby suggests macromolecular depletion as an alternative mechanism for the adhesion-promoting effects of nonadsorbing plasma proteins. These findings should not only aid in getting a better understanding of diseases associated with vascular complications but should also have many potential applications in biomedical or biotechnological areas that require the control of cell-cell or cell surface interactions.

  18. Electrophoresis release of hemoglobin from living red blood cells%活体红细胞内血红蛋白的电泳释放

    Institute of Scientific and Technical Information of China (English)

    秦文斌

    2011-01-01

    当今的蛋白质组学研究,都是先裂解细胞放出蛋白质,然后对蛋白质溶液进行各种分析.对于红细胞来说,它的裂解产物也称“溶血液”,其中主要成分有血红蛋白A1,A2,A3和碳酸酐酶(CA)等.本实验室用未裂解的完整的活体红细胞直接进行电泳,观察其释放出来的血红蛋白(hemoglobin,Hb),建立了淀粉-琼脂糖混合凝胶中红细胞的电泳释放实验.电泳释放可分为“初释放”(一次通电完成电泳,此时有Hb释放出来)和“再释放”(电泳过程中断电-再通电,又有Hb释放出来).本实验室在“初释放”实验中发现了“HbA2现象”,并通过Hb交叉电泳发现了HbA2与HbA1的相互作用;利用初释放型双向对角线电泳发现红细胞内HbA2与HbA1结合存在;对电泳释放出来的“HbA2现象”成分做SDS-PAGE及质谱分析,发现Prx-2(Peroxiredoxin-2)可能参与“HbA2现象”的形成;在研究“再释放”实验中发现了“Hb多带再释放现象”,在此基础上创建等渗再释放、低渗再释放、等低渗全程再释放及再释放型双向对角线电泳;两种红细胞(全血中的红细胞和由它分离出来的游离红细胞)再释放的比较研究;血浆成分对红细胞再释放的影响等.以上研究方法的建立为活体细胞内蛋白质存在状态的研究提供了基础,并开辟了新的研究途径和领域.%Nowadays, proteomics research is almost always made by lysing cells to release protein first and then to analyze the protein solution in many ways, the lytic product of red blood cells is also called hemolysate, the main components of which are hemoglobin A1, A2, A3 and carbonic anhydrase (CA), etc. In our laboratory, intact (unlysed) living red blood cells are used for direct electrophoresis so as to observe the released hemoglobin (Hb). Thus an electophoresis release experiment has been established with starch-agarose mixed gel. Electrophoresis release can be classified as

  19. Mapping the distribution of specific antibody interaction forces on individual red blood cells

    Science.gov (United States)

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

    2017-01-01

    Current blood typing methods rely on the agglutination of red blood cells (RBCs) to macroscopically indicate a positive result. An indirect agglutination mechanism is required when blood typing with IgG forms of antibodies. To date, the interaction forces between anti-IgG and IgG antibodies have been poorly quantified, and blood group related antigens have never been quantified with the atomic force microscope (AFM). Instead, the total intensity resulting from fluorescent-tagged antibodies adsorbed on RBC has been measured to calculate an average antigen density on a series of RBCs. In this study we mapped specific antibody interaction forces on the RBC surface. AFM cantilever tips functionalized with anti-IgG were used to probe RBCs incubated with specific IgG antibodies. This work provides unique insight into antibody-antigen interactions in their native cell-bound location, and crucially, on a per-cell basis rather than an ensemble average set of properties. Force profiles obtained from the AFM directly provide not only the anti-IgG – IgG antibody interaction force, but also the spatial distribution and density of antigens over a single cell. This new understanding might be translated into the development of very selective and quantitative interactions that underpin the action of drugs in the treatment of frontier illnesses. PMID:28157207

  20. Comparison of frozen versus desiccated reference human red blood cells for hemagglutination assays.

    Science.gov (United States)

    Ho, David; Schierts, Jennifer; Zimmerman, Zea; Gadsden, Isaac; Bruttig, Stephen

    2009-10-01

    Red blood cells (RBCs) are commonly used fresh or stored in frozen format for identification of patients' antibodies and serologic specificity of such antibodies at reference laboratories. However, maintaining a large pool of fresh RBCs is impossible in a blood-banking environment and blood in frozen format poses a logistic disadvantage in terms of accessibility, maintenance cost, safety, and sample recovery. This study explores an alternative, desiccation storage method for RBCs to provide a reagent that supports greater utilization and flexibility for reference laboratories. RBCs from five donors were used in the study. RBCs were processed and kept in either frozen or desiccated format. Study variables for either the frozen or the desiccated cells included cell recovery as quantified by cell counts, gross microscopic examination, and hemagglutination assays. The mean percentage of cell recovery for thawed and washed frozen RBCs was 20% versus 50% for rehydrated and washed desiccated RBCs. Microscopic examination of thawed cells from the frozen preparation showed cells with irregular shapes, a sharp contrast when compared with rehydrated cells from the desiccated preparation, where cells are mostly intact, smooth surface, and biconcave in structure. Cells in both preparations performed well in manual agglutination tests. Desiccation preservation of RBCs provides a somewhat better RBC recovery and cell structure stability, while maintaining the necessary antigen-antibody reactions for cell surface markers, which will allow desiccated RBCs to be archived in blood collecting and processing reference laboratories.

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

    Science.gov (United States)

    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.

  2. Modeling the Behavior of Red Blood Cells within the Caudal Vein Plexus of Zebrafish

    Science.gov (United States)

    Djukic, Tijana R.; Karthik, Swapna; Saveljic, Igor; Djonov, Valentin; Filipovic, Nenad

    2016-01-01

    Due to the important biological role of red blood cells (RBCs) in vertebrates, the analysis of reshaping and dynamics of RBCs motion is a critical issue in physiology and biomechanics. In this paper the behavior of RBCs within the immature capillary plexus during embryonic development of zebrafish has been analyzed. Relying on the fact that zebrafish embryos are small and optically transparent, it is possible to image the blood flow. In this way the anatomy of blood vessels is monitored along with the circulation throughout their development. Numerical simulations were performed using a specific numerical model that combines fluid flow simulation, modeling of the interaction of individual RBCs immersed in blood plasma with the surrounding fluid and modeling the deformation of individual cells. The results of numerical simulations are in accordance with the in vivo observed region of interest within the caudal vein plexus of the zebrafish embryo. Good agreement of results demonstrates the capabilities of the developed numerical model to predict and analyze the motion and deformation of RBCs in complex geometries. The proposed model (methodology) will help to elucidate different rheological and hematological related pathologies and finally to design better treatment strategies. PMID:27774070

  3. Properties of donated red blood cell components from patients with hereditary hemochromatosis.

    Science.gov (United States)

    Sut, Caroline; Hamzeh-Cognasse, Hind; Laradi, Sandrine; Bost, Vincent; Aubrège, Christine; Acquart, Sophie; Vignal, Martine; Boutahar, Nadia; Arthaud, Charles Antoine; Ange Eyraud, Marie; Pozzetto, Bruno; Tiberghien, Pierre; Garraud, Olivier; Cognasse, Fabrice

    2017-01-01

    Red blood cells (RBCs) contain large amounts of iron, and periodic therapeutic phlebotomy is thus the main treatment for hereditary hemochromatosis (HH). However, the donation of therapeutic phlebotomy products from asymptomatic patients for transfusion purposes remains controversial. In this study, we compared the quality of RBCs obtained from HH patients with those of non-HH RBCs, within the allowed 42-day storage period. RBCs were obtained from HH patient donors and random regular blood donors by whole blood collection. RBCs were stored for up to 42 days, according to national regulations and standard blood bank conditions in France. The following variables were assessed: hematologic and biochemical results, RBC membrane and soluble inflammatory markers, and the proinflammatory potential of HH RBC supernatant toward endothelial cells in an in vitro model. There were no major differences between the two groups in terms of biophysical, biochemical, or soluble immunomodulatory factors. However, we observed small but significant differences in changes in RBC membrane proteins during storage, including increased phosphatidylserine expression and decreased hemolysis in HH compared with normal RBCs. However, there were no differences in terms of bioactivity of soluble immunomodulatory factors in the RBC supernatant during storage between HH and control donors, as determined by their effects on endothelial cells in vitro. These in vitro studies suggest that RBCs from HH patients appear, while exhibiting subtle differences, to be suitable for transfusion purposes according to currently accepted criteria. © 2016 AABB.

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

    Science.gov (United States)

    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

    2016-04-07

    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.

  5. The influence of platelets, plasma and red blood cells on functional haemostatic assays.

    Science.gov (United States)

    Bochsen, Louise; Johansson, Pär I; Kristensen, Annemarie T; Daugaard, Gedske; Ostrowski, Sisse R

    2011-04-01

    Functional whole blood haemostatic assays are used increasingly to guide transfusion therapy and monitor medical treatment and are also applied for in-vitro evaluations of the haemostatic potential of stored platelets. We investigated how the cellular and plasmatic elements, both isolated and combined, influenced the two methodologically different assays, thrombelastography (TEG) and impedance aggregometry (Multiplate). Platelet-rich plasma (200 × 10/l) or pure plasma (0 platelets), with and without added red blood cells (RBCs), hematocrit 0, 0.15 or 0.29, were produced in vitro from platelet concentrates, fresh frozen plasma and stored RBC. Pure platelets were investigated by removing plasma components from platelet concentrates by diafiltration against the platelet storage solution Intersol. Plasma was readded by diafiltration against plasma in Intersol. Haemostatic function was evaluated by TEG and Multiplate. In the TEG, increasing amounts of RBC reduced clot strength and clot kinetics (α-angle), most markedly in plasma/RBC without platelets. In contrast, RBC in a platelet concentrate matrix enhanced Multiplate aggregation in response to weak agonists (ADP and arachidonic acid). Furthermore, removing plasma from platelet concentrates eliminated the TEG response and diminished the Multiplate aggregation response, but readding plasma to the pure platelet concentrates restored the response. Each of the elements in whole blood, plasma, platelets and RBC, affected the Multiplate and TEG results differently. The results emphasize that the concentrations of all cellular and plasmatic components in whole blood should be taken into account when interpreting results obtained by TEG and multiplate.

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

    Science.gov (United States)

    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.

  7. Modeling the Behavior of Red Blood Cells within the Caudal Vein Plexus of Zebrafish.

    Science.gov (United States)

    Djukic, Tijana R; Karthik, Swapna; Saveljic, Igor; Djonov, Valentin; Filipovic, Nenad

    2016-01-01

    Due to the important biological role of red blood cells (RBCs) in vertebrates, the analysis of reshaping and dynamics of RBCs motion is a critical issue in physiology and biomechanics. In this paper the behavior of RBCs within the immature capillary plexus during embryonic development of zebrafish has been analyzed. Relying on the fact that zebrafish embryos are small and optically transparent, it is possible to image the blood flow. In this way the anatomy of blood vessels is monitored along with the circulation throughout their development. Numerical simulations were performed using a specific numerical model that combines fluid flow simulation, modeling of the interaction of individual RBCs immersed in blood plasma with the surrounding fluid and modeling the deformation of individual cells. The results of numerical simulations are in accordance with the in vivo observed region of interest within the caudal vein plexus of the zebrafish embryo. Good agreement of results demonstrates the capabilities of the developed numerical model to predict and analyze the motion and deformation of RBCs in complex geometries. The proposed model (methodology) will help to elucidate different rheological and hematological related pathologies and finally to design better treatment strategies.

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

    Science.gov (United States)

    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.

  9. Red blood cells from induced pluripotent stem cells: hurdles and developments.

    Science.gov (United States)

    Mazurier, Christelle; Douay, Luc; Lapillonne, Hélène

    2011-07-01

    In the context of chronic blood supply difficulties, generating cultured red blood cells (cRBCs) in vitro after amplification of stem cells makes sense. This review will focus on the recent findings about the generation of erythroid cells from induced pluripotent stem (iPS) cells and deals with the hurdles and next developments that will occur. The most proliferative source of stem cells for generating cRBCs is the cord blood, but this source is limited in terms of hematopoietic stem cells and dependent on donations. Pluripotent stem cells are thus the best candidates and potential sources of cRBCs. Critical advances have led towards the in-vitro production of functional RBCs from iPS cells in the last few years. Because iPS cells can proliferate indefinitely and can be selected for a phenotype of interest, they are potential candidates to organize complementary sources of RBCs for transfusion. Proof of concept of generating cRBCs from iPS cells has been performed, but the procedures need to be optimized to lead to clinical application in blood transfusion. Several crucial points remain to be resolved. Notably these include the choice of the initial cell type to generate iPS cells, the method of reprogramming, that is, to ensure the safety of iPS cells as clinical grade, the optimization of erythrocyte differentiation, and the definition of good manufacturing practice (GMP) conditions for industrial production.

  10. Mapping the distribution of specific antibody interaction forces on individual red blood cells

    Science.gov (United States)

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

    2017-02-01

    Current blood typing methods rely on the agglutination of red blood cells (RBCs) to macroscopically indicate a positive result. An indirect agglutination mechanism is required when blood typing with IgG forms of antibodies. To date, the interaction forces between anti-IgG and IgG antibodies have been poorly quantified, and blood group related antigens have never been quantified with the atomic force microscope (AFM). Instead, the total intensity resulting from fluorescent-tagged antibodies adsorbed on RBC has been measured to calculate an average antigen density on a series of RBCs. In this study we mapped specific antibody interaction forces on the RBC surface. AFM cantilever tips functionalized with anti-IgG were used to probe RBCs incubated with specific IgG antibodies. This work provides unique insight into antibody-antigen interactions in their native cell-bound location, and crucially, on a per-cell basis rather than an ensemble average set of properties. Force profiles obtained from the AFM directly provide not only the anti-IgG – IgG antibody interaction force, but also the spatial distribution and density of antigens over a single cell. This new understanding might be translated into the development of very selective and quantitative interactions that underpin the action of drugs in the treatment of frontier illnesses.

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

    Science.gov (United States)

    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.

  12. The significant blood resistance to lung nitric oxide transfer lies within the red cell.

    Science.gov (United States)

    Borland, Colin; Bottrill, Fiona; Jones, Aled; Sparkes, Chris; Vuylsteke, Alain

    2014-01-01

    The lung nitric oxide (NO) diffusing capacity (DlNO) mainly reflects alveolar-capillary membrane conductance (Dm). However, blood resistance has been shown in vitro and in vivo. To explore whether this resistance lies in the plasma, the red blood cell (RBC) membrane, or in the RBC interior, we measured the NO diffusing capacity (Dno) in a membrane oxygenator circuit containing ∼1 liter of horse or human blood exposed to 14 parts per million NO under physiological conditions on 7 separate days. We compared results across a 1,000-fold change in extracellular diffusivity using dextrans, plasma, and physiological salt solution. We halved RBC surface area by comparing horse and human RBCs. We altered the diffusive resistance of the RBC interior by adding sodium nitrite converting oxyhemoglobin to methemoglobin. Neither increased viscosity nor reduced RBC size reduced Dno. Adding sodium nitrite increased methemoglobin and was associated with a steady fall in Dno (P < 0.001). Similar results were obtained at NO concentrations found in vivo. The RBC interior appears to be the site of the blood resistance.

  13. Prevalence and specificities of red cell alloantibodies among blood recipients in the Malaysian state of Kelantan.

    Science.gov (United States)

    Al-Joudi, Fawwaz; Ali, Anuar Bin; Ramli, Majdan Bin; Ahmed, Suhair; Ismail, Mohd

    2011-01-01

    Red blood cell (RBC) alloantibodies may be formed following exposure to RBC antigens. In most cases, the alloimmunization develops during pregnancy or from previous blood transfusions. The RBC antigens and their alloantibodies vary among different human populations and ethnic groups, and they do have a clinical significance for their adverse immunological reactions. This study aimed at studying the prevalence of RBC alloantibodies at the Blood Transfusion Unit of Hospital Raja Perempuan Zainab II in Kota Bharu, Malaysia. A cross-sectional study was performed utilizing data obtained in the years 2007 and 2008. Data of antibody screening tests from 5719 patients were examined. The overall prevalence of alloimmunization was 65 (1.13%). The majority of these had a single alloantibody (76.9%), whereas the remaining 23.1% had multiple antibodies. The anti-E antibody comprised the most common alloantibody (24.6%) followed by the anti-Lewis (a) antibodies (18.5%) and the anti-M antibody (13.8%). There were more female recipients than males. It was concluded that the findings of this work have been comparable with other published works, and that the main factors associated with alloantibody formation were multiple transfusions and pregnancies. The study also emphasizes the necessity for carrying out immunohematology studies prior to every blood transfusion especially in cases that require multiple transfusions for a long period of time such as in thalassemia patients.

  14. Correlation of discocyte frequency and ATP concentration in preserved blood: A morphological indicator of red blood cell viability

    Directory of Open Access Journals (Sweden)

    Leonart M.S.S.

    1997-01-01

    Full Text Available Red blood cells (RBC are viable if kept in an adequate preservative solution, although gradual changes in morphology and metabolism may occur. There is a gradual decrease in adenosine-5'-triphosphate (ATP concentration, pH, glucose consumption, and enzyme activity during preservation. The normal discocyte shapes are initially replaced by echinocytes and stomatocytes and, at final stages, by spherocytes, the last step before splenic sequestration. Post-transfusional survival has been correlated with the ATP concentration. RBC preserved in ADSOL, a solution containing adenine, dextrose, sodium chloride, and mannitol, are viable for transfusion for up to 6 weeks. Erythrocytes from 10 blood units taken from healthy adult donors were preserved for 12 weeks in ADSOL at 4oC. We now report a significant correlation (r2 = 0.98 between the percentage of discocytes (89 to 7% and ATP (100 to 10% concentration in ADSOL-preserved RBC. The results suggest that the percent of discocyte shapes used as an indicator of ATP concentration may be a useful indicator for quality control of RBC viability in centers which have limited assay facilities.

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

    LENUS (Irish Health Repository)

    Pettila, Ville

    2011-04-15

    Abstract 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.

  16. p-Chloromercuribenzoate-induced dissociation of cytoskeletal proteins in red blood cells of rats.

    Science.gov (United States)

    Kunimoto, M; Shibata, K; Miura, T

    1987-12-11

    Effects of p-chloromercuribenzoate (PCMB) on the cytoskeletal organization of rat red blood cells were studied. Upon incubation with 50 microM PCMB in 10 mM Tris-HCl (pH 7.4) at 37 degrees C for 30 min, 80% of actin and 45% of spectrin were released from the ghosts, resulting in the fragmentation of ghost membranes. Addition of 2 mM Mg2+ or 0.1 M KCl, or lowering incubation temperature to 0 degree C substantially inhibited the solubilization of the cytoskeletal proteins and the fragmentation of ghost membranes, which enable to examine the effects of PCMB on the interaction between transmembrane proteins and the peripheral cytoskeletal network. Decreased recoveries of transmembrane proteins, such as band 3 and glycophorin, in Triton shell fraction were observed in the ghosts incubated with PCMB either in the presence of Mg2+ or at 0 degree C. PCMB also inhibited the in vitro association of purified spectrin with spectrin-depleted inside-out vesicles through interaction with proteins in the vesicle, such as bands 2.1 and 3. In the PCMB-treated ghosts, intramembrane particles were highly aggregated, which further supports the PCMB-induced dissociation of the transmembrane proteins from the cytoskeletal network. The decreased recovery of glycophorin in the Triton shell fraction also observed in intact red blood cells upon incubation with PCMB. These results suggest that the main action of PCMB on red cell membranes under physiological condition, at higher ionic strength and in the presence of Mg2+, is to dissociate transmembrane proteins from the peripheral cytoskeletal network, which may modify functions of these proteins.

  17. Levels of carnitine and acylcarnitines in reconstituted red blood cell samples washed with different concentrations of saline solutions

    OpenAIRE

    José Henry Osorio; Morteza Pourfarzam

    2011-01-01

    Objective: To evaluate the percentage of carnitine and acylcarnitines remaining in red blood cells after washing them with different concentrations of saline solution. Materials and methods: Human blood samples were centrifuged and the blood cells were washed with different saline solutions. The final pellet was resuspended in PBS for card preparation and tandem mass spectrometry analysis. Results: It was found that carnitine, as well as short-chain, medium-chain, and long-chain acylca...

  18. T-matrix computations of light scattering by red blood cells.

    Science.gov (United States)

    Nilsson, A M; Alsholm, P; Karlsson, A; Andersson-Engels, S

    1998-05-01

    The electromagnetic far field, as well as the near field, originating from light interaction with a red blood cell (RBC)volume-equivalent spheroid, was analyzed by utilizing theT-matrix theory. This method is a powerful tool thatmakes it possible to study the influence of cell shape on the angulardistribution of scattered light. General observations were that thethree-dimensional shape, as well as the optical thickness apparent tothe incident field, affects the forward scattering. Thebackscattering was influenced by the shape of the surface facing theincident beam. Furthermore sphering as well as elongation of anoblate RBC into a volume-equivalent sphere or a prolate spheroid, respectively, was theoretically modeled to imitate physiologicalphenomena caused, e.g., by heat or the increased shear stress offlowing blood. Both sphering and elongation were shown to decreasethe intensity of the forward-directed scattering, thus yielding lowerg factors. The sphering made the scattering patternindependent of azimuthal scattering angle phi(s), whereas the elongation induced more apparent phi(s)-dependent patterns. The lightscattering by a RBC volume-equivalent spheroid was thus found to behighly influenced by the shape of the scattering object. Anear-field radius r(nf) was evaluated as thedistance to which the maximum intensity of the total near field haddecreased to 2.5 times that of the incident field. It was estimatedto 2-24.5 times the maximum radius of the scattering spheroid, corresponding to 12-69 mum. Because the near-field radiuswas shown to be larger than a simple estimation of the distance betweenthe RBC's in whole blood, the assumption of independent scattering, frequently employed in optical measurements on whole blood, seemsinappropriate. This also indicates that one cannot extrapolate theresults obtained from diluted blood to whole blood by multiplying witha simple concentration factor.

  19. Bioinformatic prediction of the exportome of Babesia bovis and identification of novel proteins in parasite-infected red blood cells.

    Science.gov (United States)

    Gohil, Sejal; Kats, Lev M; Seemann, Torsten; Fernandez, Kate M; Siddiqui, Ghizal; Cooke, Brian M

    2013-04-01

    Babesia bovis is a pathogen of considerable economic significance to the livestock industry worldwide but the precise mechanisms by which this parasite causes disease in susceptible cattle remain poorly understood. It is clear, however, that alterations to the structure and function of red blood cells in which the parasites reside and replicate play an important role in pathogenesis and that these are secondary to the export of numerous, currently unknown and uncharacterised parasite-encoded proteins. Using a rational bioinformatic approach, we have identified a set of 362 proteins (117 of which are hypothetical) that we predict encompasses the B. bovis exportome. These exported proteins are likely to be trafficked to various cellular locations, with a subset destined for the red blood cell cytosol or the red blood cell cytoskeleton. These proteins are likely to play important roles in mediating the pathogenesis of babesiosis. We have selected three novel proteins and confirmed their predicted export and localisation within the host red blood cell by immunofluorescence using specific antibodies raised against these proteins. Complete characterisation of these novel exported parasite proteins will help elucidate their function within the host red blood cell and assist in identification of new therapeutic targets for babesiosis.

  20. Apoptosis and morphological alterations after UVA irradiation in red blood cells of p53 deficient Japanese medaka (Oryzias latipes).

    Science.gov (United States)

    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.

  1. Effect of Korean red ginseng on blood pressure and nitric oxide production

    Institute of Scientific and Technical Information of China (English)

    JEON Byeong Hwa; KIM Cuk Seong; KIM Hoe-Suk; PARK Jin-Bong; NAM Ki Yeul; CHANG Seok Jong

    2000-01-01

    AIM: To investigate the effect of crude saponin and nonsaponin fraction of Korean red ginseng (KRG) on the blood pressure and nitric oxide (NO) production in the conscious rats and cultured endothelial cell line, FCV 304 cells. METHODS: Systolic blood pressure and heart rate were monitored in the conscious rats. Nitric oxide levels and the expression of nitric oxide synthase were measured by a spectrophotometric assay using Griess reagents and Western blotting, respectively. Nitric-oxide synthase activity was measured based on the conversion rate of [3H]arginine to [3H]citmlline. RESUITS: Systolic blood pressure was decreased by crude saponin (100 mg/kg, iv) of KRG in the conscious control and one-kidney, one-clip Goldblatt hypertensive (1K, 1C-GBH) rats. The hypotensive effect induced by crude saponin of KRG reached maximum at 2 - 4 min and slowly recovered after 20 min to the initial level in both groups. Crude saponin of KRG induced tacliycardia in the conscious rats but induced bradycardia in the anesthetized rats. In contrast to crude saponin of KRG, hypotensive effect induced by saponin-free fraction was minimal. Nitric oxide concentrations were increased by the treaunent of crude saponin in conscious rats as well as in the cultured FCV 304 cells. The protein expression level of endothelial constitutive nitric-oxide synthase (eNOS) in the aorta of rats was not increased by crude saponin (100 mg/kg, ip for 3 d). However, nitric-oxide synthase activity was increased by crude saponin of KRG in the aortic homogenate of rats. CONCLUSION: The hypotensive effect of red ginseng is mainly due to saponin fraction of KRG in the conscious rats, and this effect may be due to an increase in the nitric-oxide production by KRG.

  2. Two-dimensional simulation of red blood cell motion near a wall under a lateral force

    Science.gov (United States)

    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.

  3. Proteins involved in invasion of human red blood cells by malaria parasites

    Directory of Open Access Journals (Sweden)

    Ewa Jaśkiewicz

    2010-11-01

    Full Text Available Malaria is a disease caused by parasites of Plasmodium species. It is responsible for around 1-2 million deaths annually, mainly children under the age of 5. It occurs mainly in tropical and subtropical areas.Malaria is caused by five Plasmodium species:[i] P. falciparum, P. malariae, P. vivax, P. knowlesi[/i] and [i]P. ovale[/i]. Mosquitoes spread the disease by biting humans. The malaria parasite has two stages of development: the human stage and the mosquito stage. The first stage occurs in the human body and is divided into two phases: the liver phase and the blood phase.The invasion of erythrocytes by [i]Plasmodium[/i] merozoites is a multistep process of specific protein interactions between the parasite and red blood cell. The first step is the reversible merozoite attachment to the erythrocyte followed by its apical reorientation, then formation of an irreversible “tight” junction and finally entry into the red cell in a parasitophorous vacuole.The blood phase is supported by a number of proteins produced by the parasite. The merozoite surface GPI-anchored proteins (MSP-1, 2, 4, 5, 8 and 10 assist in the process of recognition of susceptible erythrocytes, apical membrane antigen (AMA-1 may be directly responsible for apical reorientation of the merozoite and apical proteins which function in tight junction formation. These ligands are members of two families: Duffy binding-like (DBL and reticulocyte binding-like (RBL proteins. In [i]Plasmodium[/i] [i]falciparum[/i] the DBL family includes: EBA-175, EBA-140 (BAEBL, EBA-181 (JESEBL, EBA-165 (PEBL and EBL-1 ligands.To date, no effective antimalarial vaccine has been developed, but there are several studies for this purpose. Therefore, it is crucial to understand the molecular basis of host cells invasion by parasites. Major efforts are focused on developing a multiantigenic and multiepitope vaccine preventing all steps of [i]Plasmodium[/i] invasion.

  4. Local membrane deformations activate Ca2+-dependent K+ and anionic currents in intact human red blood cells

    DEFF Research Database (Denmark)

    Dyrda, Agnieszka; Cytlak, Urszula; Ciuraszkiewicz, Anna

    2010-01-01

    by such flow, as well as the local membrane deformations generated in certain pathological conditions, such as sickle cell anemia, have been shown to increase membrane permeability, based largely on experimentation with red cell suspensions. We attempted here the first measurements of membrane currents......-activated transient PCa observed here under local membrane deformation is a likely contributor to the Ca(2+)-mediated effects observed during the normal aging process of red blood cells, and to the increased Ca(2+) content of red cells in certain hereditary anemias such as thalassemia and sickle cell anemia.......BACKGROUND: The mechanical, rheological and shape properties of red blood cells are determined by their cortical cytoskeleton, evolutionarily optimized to provide the dynamic deformability required for flow through capillaries much narrower than the cell's diameter. The shear stress induced...

  5. Packed red blood cells are an abundant and proximate potential source of nitric oxide synthase inhibition.

    Directory of Open Access Journals (Sweden)

    Charles F Zwemer

    Full Text Available We determined, for packed red blood cells (PRBC and fresh frozen plasma, the maximum content, and ability to release the endogenous nitric oxide synthase (NOS inhibitors asymmetric dimethylarginine (ADMA and monomethylarginine (LNMMA.ADMA and LNMMA are near equipotent NOS inhibitors forming blood's total NOS inhibitory content. The balance between removal from, and addition to plasma determines their free concentrations. Removal from plasma is by well-characterized specific hydrolases while formation is restricted to posttranslational protein methylation. When released into plasma they can readily enter endothelial cells and inhibit NOS. Fresh rat and human whole blood contain substantial protein incorporated ADMA however; the maximum content of ADMA and LNMMA in PRBC and fresh frozen plasma has not been determined.We measured total (free and protein incorporated ADMA and LNMMA content in PRBCs and fresh frozen plasma, as well as their incubation induced release, using HPLC with fluorescence detection. We tested the hypothesis that PRBC and fresh frozen plasma contain substantial inhibitory methylarginines that can be released chemically by complete in vitro acid hydrolysis or physiologically at 37°C by enzymatic blood proteolysis.In vitro strong-acid-hydrolysis revealed a large PRBC reservoir of ADMA (54.5 ± 9.7 µM and LNMMA (58.9 ± 28.9 μM that persisted over 42-d at 6° or -80°C. In vitro 5h incubation at 37°C nearly doubled free ADMA and LNMMNA concentration from PRBCs while no change was detected in fresh frozen plasma.The compelling physiological ramifications are that regardless of storage age, 1 PRBCs can rapidly release pathologically relevant quantities of ADMA and LNMMA when incubated and 2 PRBCs have a protein-incorporated inhibitory methylarginines reservoir 100 times that of normal free inhibitory methylarginines in blood and thus could represent a clinically relevant and proximate risk for iatrogenic NOS inhibition upon

  6. Magnetic red blood cells as new contrast agents for MRI applications

    Science.gov (United States)

    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.

  7. Optical tweezers for measuring the interaction of the two single red blood cells in flow condition

    Science.gov (United States)

    Lee, Kisung; Muravyov, Alexei; Semenov, Alexei; Wagner, Christian; Priezzhev, Alexander

    2017-03-01

    Aggregation of red blood cells (RBCs) is an intrinsic property of blood, which has direct effect on the blood viscosity and therefore affects overall the blood circulation throughout the body. It is attracting interest for the research in both fundamental science and clinical application. Despite of the intensive research, the aggregation mechanism is remaining not fully clear. Recent advances in methods allowed measuring the interaction between single RBCs in a well-defined configuration leading the better understanding of the mechanism of the process. However the most of the studies were made on the static cells. Thus, the measurements in flow mimicking conditions are missing. In this work, we aim to study the interaction of two RBCs in the flow conditions. We demonstrate the characterization of the cells interaction strength (or flow tolerance) by measuring the flow velocity to be applied to separate two aggregated cells trapped by double channel optical tweezers in a desired configuration. The age-separated cells were used for this study. The obtained values for the minimum flow velocities needed to separate the two cells were found to be 78.9 +/- 6.1 μm/s and 110 +/- 13 μm/s for old and young cells respectively. The data obtained is in agreement with the observations reported by other authors. The significance of our results is in ability for obtaining a comprehensible and absolute physical value characterizing the cells interaction in flow conditions (not like the Aggregation Index measured in whole blood suspensions by other techniques, which is some abstract parameter)

  8. Reduction in potassium concentration of stored red blood cell units using a resin filter.

    Science.gov (United States)

    Yamada, Chisa; Heitmiller, Eugenie S; Ness, Paul M; King, Karen E

    2010-09-01

    Hyperkalemia is a serious complication of rapid and massive blood transfusion due to high plasma potassium (K) in stored red blood cell (RBC) units. A potassium adsorption filter (PAF) was developed in Japan to remove K by exchanging with sodium (Na). We performed an in vitro evaluation of its efficacy and feasibility of use. Three AS-3 RBC units were filtered by each PAF using gravity; 10 PAFs were tested. Blood group, age, flow rate, and irradiation status were recorded. Total volume, K, Na, Cl, Mg, total Ca (tCa), RBC count, hemoglobin (Hb), hematocrit (Hct), and plasma Hb were measured before and after filtering each unit. Ionized Ca (iCa), pH, and glucose were measured for some units. After filtration, the mean decrease in K was 97.5% in the first RBC unit, 91.2% in the second unit, and 64.4% in the third unit. The mean increases in Na, Mg, and tCa were 33.0, 151.4, and 116.1%, respectively. iCa and pH remained low; glucose was unchanged. RBC count, Hb, and Hct decreased slightly after filtration of first units; plasma Hb was unchanged. After filtration, there was no visual evidence of increased hemolysis or clot formation. The PAF decreased K concentration in stored AS-3 RBC units to minimal levels in the first and second RBC units. Optimally, one filter could be used for 2 RBC units. Although Na increased, the level may not be clinically significant. PAF may be useful for at-risk patients receiving older units or blood that has been stored after gamma irradiation. © 2010 American Association of Blood Banks.

  9. Red wine with the noon meal lowers post-meal blood pressure: a randomized trial in centrally obese, hypertensive patients.

    Science.gov (United States)

    Foppa, Murilo; Fuchs, Flávio D; Preissler, Lisângela; Andrighetto, André; Rosito, Guido A; Duncan, Bruce B

    2002-03-01

    Despite being recognized as a cause of hypertension at higher doses, consumption of lesser amounts of alcohol appears to protect against cardiovascular disease and acutely reduces blood pressure. We tested the hypothesis that two glasses of red wine, taken together with the noon meal, would cause postprandial reduction in blood pressure in hypertensive individuals. Thirteen (8 female) middle-aged, centrally obese, hypertensive and otherwise healthy participants received, in an open randomized crossover experiment, red wine (250 ml to approximately 23 g of ethanol) and a placebo equivalent, together with a standardized lunch. Blood pressure was measured with 24-hour ambulatory monitoring. Wine with the meal produced a mean (SD) reduction of 5.3 (7.66) mmHg in postprandial blood pressure (p = .03), which persisted for most of the remaining daytime interval. The maximal blood pressure reduction was 8.5 (11.84) mmHg, occurring 3 hours after intervention (p = .02). In addition, nocturnal dipping in systolic blood pressure was lessened during the wine intervention period (5.3 [10.19] vs 11.1 [8.08] mmHg; p = .03). Ingestion of 250 ml of red wine, together with the noon meal, resulted in reduction of the postprandial blood pressure of centrally obese, hypertensive subjects. The effect lasted throughout most of the remaining daytime interval and appeared to modify the usual blood pressure variation pattern.

  10. Single-Beam Acoustic Trapping of Red Blood Cells and Polystyrene Microspheres in Flowing Red Blood Cell Saline and Plasma Suspensions.

    Science.gov (United States)

    Liu, Hsiao-Chuan; Li, Ying; Chen, Ruimin; Jung, Hayong; Shung, K Kirk

    2017-02-21

    Single-beam acoustic tweezers (SBATs) represent a new technology for particle and cell trapping. The advantages of SBATs are their deep penetration into tissues, reduction of tissue damage and ease of application to in vivo studies. The use of these tools for applications in drug delivery in vivo must meet the following conditions: large penetration depth, strong trapping force and tissue safety. A reasonable penetration depth for SBATs in the development of in vivo applications was established in a previous study conducted in water with zero velocity. However, capturing objects in flowing fluid can provide more meaningful results. In this study, we investigated the capability of SBATs to trap red blood cells (RBCs) and polystyrene microspheres in flowing RBC suspensions. Two different types of RBC suspension were prepared in this work: an RBC phosphate-buffered saline (PBS) suspension and an RBC plasma suspension. The results indicated that SBATs successfully trapped RBCs and polystyrene microspheres in a flowing RBC PBS suspension with an average steady velocity of 1.6 cm/s in a 2-mm-diameter polyimide. Furthermore, SBATs were found able to trap RBCs in a flowing RBC PBS suspension at speeds as high as 7.9 cm/s in a polyimide tube, which is higher than the velocity in capillaries (0.03 cm/s) and approaches the velocity in arterioles and venules. Moreover, the results also indicated that polystyrene microspheres can be trapped in an RBC plasma suspension, where aggregation is observed. This work represents a step forward in using this tool in actual in vivo experimentation.

  11. IgG red blood cell autoantibodies in autoimmune hemolytic anemia bind to epitopes on red blood cell membrane band 3 glycoprotein

    Energy Technology Data Exchange (ETDEWEB)

    Victoria, E.J.; Pierce, S.W.; Branks, M.J.; Masouredis, S.P. (Univ. of California, San Diego (USA))

    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.

  12. Analysis of membrane tank-tread of nonspherical capsules and red blood cells.

    Science.gov (United States)

    Bagchi, P; Yazdani, A Z K

    2012-10-01

    We present an analysis of membrane motion of deformable capsules and red blood cells suspended in a linear shear flow and undergoing swinging and tumbling motions using three-dimensional numerical simulations. This study is motivated by the theory of the shape-preserving cells which predicts that the direction of the membrane rotation depends on the cell orientation and reverses at every 45° inclination angle of the cell major axis with respect to the external flow direction. By considering large deformation of capsules and red blood cells, here we investigate how the shape oscillation affects the time dependence and the direction reversal of the membrane rotation. We find that the membrane tank-tread is highly time-dependent in nature and synchronized with the time-dependent deformation. The maximum and minimum of the tank-tread velocity occur at and near the minimum and maximum deformation, respectively. For the swinging capsules and red blood cells, the direction of the membrane rotation is always along the direction of the external fluid rotation; however, a direction reversal occurs during the tumbling motion in which case the membrane rotates in the direction of the external fluid rotation when the major axis is mostly in the extensional quadrant of the shear flow, and in the opposite direction when it is mostly in the compressional quadrant. Unlike the theory which predicts the direction reversal at every 45° inclination angle irrespective of the control parameters, namely, the capillary number, viscosity ratio, and asphericity, we find that the angle at which the direction reversal occurs depends on these parameters. In particular, if the tumbling motion occurs by decreasing the capillary number, the membrane rotation is in the direction of the external flow rotation in the entire extensional quadrant, but in the opposite direction in the compressional quadrant, irrespective of the specific values of the capillary number. If the tumbling motion occurs by

  13. Proton fluxes associated with the Ca pump in human red blood cells

    Energy Technology Data Exchange (ETDEWEB)

    Milanick, M.A. (Univ. of Missouri School of Medicine, Columbia (USA))

    1990-03-01

    Ca fluxes and H fluxes were measured in human red blood cells at 37 degrees C to characterize the effects of extracellular protons (Hout) on the Ca pump and to determine the stoichiometry of Ca-H exchange. A pH-stat technique was used to measure the rate of H influx, and 45Ca was used to determine the rate of Ca efflux. 4,4'-Diisothiocyanostilbene-2,2'-disulfonic acid (DIDS) was used to reduce proton permeability. A La-sensitive H influx was observed in Ca-loaded cells (Ca = 2 mmol/l packed cells) and was not observed in the cells loaded with vanadate as well as Ca. Similar results were obtained in Ca-loaded ghosts. The La dose-response curves for H influx and for Ca efflux were similar (50% inhibitory concentration (IC50) = approximately 5 microM) in intact red blood cells. The stoichiometry of the La-sensitive fluxes among different experiments ranged from 1.7 to 2.1 H/Ca when extracellular pH (pHout) = 6.3. Thus the Ca pump in intact red blood cells mediates Ca-2H exchange at pHout = 6.3. A 100-fold decrease in Hout (from pH 6.5 to 8.5; intracellular pH (pHin) approximately 7.4) only decreased Ca efflux 1.5- to 3-fold, hence Hout had little effect on the overall rate under the conditions studied. The small effect of Hout was a surprising result for a Ca-H exchange system, since one would have expected a steep dependence of Ca pump on Hout at Hout less than the Michaelis constant (Km). However, no La-sensitive H influx was observed when pHout = 8. On the basis of these data, it is suggested that the Ca pump also mediates Ca efflux uncoupled from H influx (Ca2+/phi H+). Ca efflux in the presence of 11 mM extracellular Ca (Caout) was one-fifth the value obtained in the absence of Caout at pHout = 8.5; this inhibition was reversed by increasing Hout (to pH 6.1).

  14. Simplification of a pharmacokinetic model for red blood cell methotrexate disposition.

    Science.gov (United States)

    Pan, Shan; Korell, Julia; Stamp, Lisa K; Duffull, Stephen B

    2015-12-01

    A pharmacokinetic (PK) model is available for describing the time course of the concentrations of methotrexate (MTX or MTXGlu1) and its active polyglutamated metabolites (MTXGlu2-5) in red blood cells (RBCs). In this study, we aimed to simplify the MTX PK model and to optimise the blood sampling schedules for use in future studies. A proper lumping technique was used to simplify the original MTX RBC PK model. The sum of predicted RBC MTXGlu3-5 concentrations in both the simplified and original models was compared. The sampling schedules for MTXGlu3-5 or all MTX polyglutamates in RBCs were optimised using the Population OPTimal design (POPT) software. The MTX RBC PK model was simplified into a three-state model. The maximum of the absolute value of relative difference in the sum of predicted RBC MTXGlu3-5 concentrations over time was 6.3 %. A five blood sample design was identified for estimating parameters of the simplified model. This study illustrates the application of model simplification processes to an existing model for MTX RBC PK. The same techniques illustrated in our study may be adopted by other studies with similar interest.

  15. Indolic Uremic Solutes Enhance Procoagulant Activity of Red Blood Cells through Phosphatidylserine Exposure and Microparticle Release

    Directory of Open Access Journals (Sweden)

    Chunyan Gao

    2015-10-01

    Full Text Available 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.

  16. Variation of Red Blood Cell Distribution Width and Mean Platelet Volume after Moderate Endurance Exercise

    Directory of Open Access Journals (Sweden)

    Giuseppe Lippi

    2014-01-01

    Full Text Available 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.

  17. Serotonin is a key factor for mouse red blood cell survival.

    Directory of Open Access Journals (Sweden)

    Pascal Amireault

    Full Text Available Serotonin (5-HT is a monoamine originally purified from blood as a vasoactive agent. In nonneuronal tissues, its presence is linked with the expression of tryptophan hydroxylase 1 (TPH1 that catalyzes the rate-limiting step of its synthesis. Targeted disruption in mice of the TPH1 gene results in very low levels of circulating 5-HT. Previous analysis of the TPH1 knockout (TPH1(-/- mouse revealed that they develop a phenotype of macrocytic anemia with a reduced half-life of their circulating red blood cells (RBC. In this study, to establish whether the observed reduced half-life of TPH1(-/- RBC is an intrinsic or an extrinsic characteristic, we compared their survival to RBC isolated from wild-type mice. Both in vivo and in vitro data converge to demonstrate an extrinsic protective effect of 5-HT since presence of 5-HT in the RBC environment protects RBC from senescence. The protective effect played by 5-HT is not mediated through activation of a classical pharmacological pathway as no 5-HT receptors were detected on isolated RBC. Rather, 5-HT acts as an effective antioxidant since reduction of 5-HT circulating levels are associated with a decrease in the plasma antioxidant capacity. We further demonstrate a link between oxidation and the removal of damaged RBC following transfusion, as supplementation with 5-HT improves RBC post-transfusion survival in a mouse model of blood banking.

  18. Influence of the bn gene on mitosis of immature red blood cells in turkeys.

    Science.gov (United States)

    Searle, B M; Bloom, S E

    1979-01-01

    The binucleated and large mononucleated red blood cells found in the blood of bnbn mutant turkeys result from nondisjunction of chromosomes in bone marrow polychromatic erythrocytes. The major ultrastructural abnormality that is observed in these mutant cells is malpositioning of the centrioles in the cell. This involves failure to assume a normal pole-to-pole position in the center of the cell, and, often, centrioles are seen close together near the cell membrane. In addition to the abnormalities in centrioles, incomplete spindles are formed with large masses of chromatin unattached to microtubules. Cytokinesis is blocked in many instances because large amounts of chromatin remain at the region of the metaphase plate. None of the aforementioned abnormalities were seen in bone marrow cells from genetically normal turkeys. The results of this study suggest that malorientation of the centrioles has adverse effects on chromosome movement in animal cells. The concept that the spatial orientation of the centrioles is fundamental in achieving normal separation of chromosomes during anaphase movement is supported by our work. Finally, the close ultrastructural parallels with the human blood disease congenital dyserythropoietic anemia type I are discussed.

  19. A study of red blood cell deformability in diabetic retinopathy using optical tweezers

    Science.gov (United States)

    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.

  20. Influence of Red Blood Cells on Nanoparticle Targeted Delivery in Microcirculation

    Science.gov (United States)

    Tan, Jifu; Thomas, Antony; Liu, Yaling

    2011-11-01

    In this paper, a particle-cell hybrid model is developed to model Nanoparticle (NP) transport, dispersion, and binding dynamics in blood suspension under the influence of Red blood cells (RBCs). The motion and deformation of RBCs is captured through the Immersed Finite Element Method. The motion and adhesion of individual NPs are tracked through Brownian adhesion dynamics. A mapping algorithm and an interaction potential function are introduced to consider the cell-particle collision. NP dispersion and binding rates are derived from the developed model under various rheology conditions. The influence of RBCs, vascular flow rate, and particle size on NP distribution and delivery efficacy is characterized. A non-uniform NP distribution profile with higher particle concentration near the vessel wall is observed. Such distribution leads to over 50% higher particle binding rate compared to the case without RBC considered. The tumbling motion of RBCs in the core region of the capillary is found to enhance NP dispersion, with dispersion rate increases as shear rate increases. Results from this study contribute to the fundamental understanding and knowledge on how the particulate nature of blood influences NP delivery, which will provide mechanistic insights on the nanomedicine design for targeted drug delivery applications.

  1. Stimulation of human red blood cells leads to Ca2+-mediated intercellular adhesion

    CERN Document Server

    Steffen, Patrick; Nguyen, Duc Bach; Müller, Torsten; Bernhardt, Ingolf; Kaestner, Lars; Wagner, Christian

    2011-01-01

    Red blood cells (RBCs) are a major component of blood clots, which form physiologically as a response to injury or pathologically in thrombosis. The active participation of RBCs in thrombus solidification has been previously proposed but not yet experimentally proven. Holographic optical tweezers and single-cell force spectroscopy were used to study potential cell-cell adhesion between RBCs. Irreversible intercellular adhesion of RBCs could be induced by stimulation with lysophosphatidic acid (LPA), a compound known to be released by activated platelets. We identified Ca2+ as an essential player in the signaling cascade by directly inducing Ca2+ influx using A23187. Elevation of the internal Ca2+ concentration leads to an intercellular adhesion of RBCs similar to that induced by LPA stimulation. Using single-cell force spectroscopy, the adhesion of the RBCs was identified to be approximately 100 pN, a value large enough to be of significance inside a blood clot or in pathological situations like the vasco-occ...

  2. Inertia-dependent dynamics of three-dimensional vesicles and red blood cells in shear flow.

    Science.gov (United States)

    Luo, Zheng Yuan; Wang, Shu Qi; He, Long; Xu, Feng; Bai, Bo Feng

    2013-10-28

    A three-dimensional (3D) simulation study of the effect of inertia on the dynamics of vesicles and red blood cells (RBCs) has not been reported. Here, we developed a 3D model based on the front tracking method to investigate how inertia affects the dynamics of spherical/non-spherical vesicles and biconcave-shaped RBCs with the Reynolds number ranging from 0.1 to 10. The results showed that inertia induced non-spherical vesicles transitioned from tumbling to swinging, which was not observed in previous 2D models. The critical viscosity ratio of inner/outer fluids for the tumbling–swinging transition remarkably increased with an increasing Reynolds number. The deformation of vesicles was greatly enhanced by inertia, and the frequency of tumbling and tank-treading was significantly decreased by inertia. We also found that RBCs can transit from tumbling to steady tank-treading through the swinging regime when the Reynolds number increased from 0.1 to 10. These results indicate that inertia needs to be considered at moderate Reynolds number (Re ~ 1) in the study of blood flow in the human body and the flow of deformable particle suspension in inertial microfluidic devices. The developed 3D model provided new insights into the dynamics of RBCs under shear flow, thus holding great potential to better understand blood flow behaviors under normal/disease conditions.

  3. Transdifferentiation of Human Hair Follicle Mesenchymal Stem Cells into Red Blood Cells by OCT4

    Directory of Open Access Journals (Sweden)

    Zhijing Liu

    2015-01-01

    Full Text Available Shortage of red blood cells (RBCs, erythrocytes can have potentially life-threatening consequences for rare or unusual blood type patients with massive blood loss resulting from various conditions. Erythrocytes have been derived from human pluripotent stem cells (PSCs, but the risk of potential tumorigenicity cannot be ignored, and a majority of these cells produced from PSCs express embryonic ε- and fetal γ-globins with little or no adult β-globin and remain nucleated. Here we report a method to generate erythrocytes from human hair follicle mesenchymal stem cells (hHFMSCs by enforcing OCT4 gene expression and cytokine stimulation. Cells generated from hHFMSCs expressed mainly the adult β-globin chain with minimum level of the fetal γ-globin chain. Furthermore, these cells also underwent multiple maturation events and formed enucleated erythrocytes with a biconcave disc shape. Gene expression analyses showed that OCT4 regulated the expression of genes associated with both pluripotency and erythroid development during hHFMSC transdifferentiation toward erythroid cells. These findings show that mature erythrocytes can be generated from adult somatic cells, which may serve as an alternative source of RBCs for potential autologous transfusion.

  4. The Quality Assessment of Stored Red Blood Cells Probed Using Atomic-Force Microscopy

    Directory of Open Access Journals (Sweden)

    I. M. Lamzin

    2014-01-01

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

  5. The quality assessment of stored red blood cells probed using atomic-force microscopy.

    Science.gov (United States)

    Lamzin, I M; Khayrullin, R M

    2014-01-01

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

  6. Investigation of diseases through red blood cells' shape using photoacoustic response technique

    Science.gov (United States)

    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.

  7. Red blood cell abnormalities and the pathogenesis of anemia in end-stage renal disease.

    Science.gov (United States)

    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.

  8. Lacking deoxygenation-linked interaction between cytoplasmic domain of band 3 and HbF from fetal red blood cells

    DEFF Research Database (Denmark)

    Weber, Roy E.

    2007-01-01

    Aim: Several of the red blood cell's metabolic and membrane functions display dependence on haemoglobin oxygenation. In adult human red cells, the increased glycolytic rate at low O2 tension results from binding of deoxygenated HbA at negatively charged, N-terminal, cytoplasmic domain...... of the membrane protein band 3, which liberates glycolytic enzymes from this site. This study aims to investigate the role of fetal HbF (that has lower anion-binding capacity than HbA) in fetal red cells (that are subjected to low O2 tensions), and to elucidate possible linkage (e.g. via the major red cell...... membrane organising centre, band 3) between the individual oxygenation-linked reactions encountered in red cells. Methods: The interaction between band 3 and Hb is analysed in terms of the effects, measured under different conditions, of a 10-mer peptide that corresponds to the N-terminus of human band 3...

  9. Investigation of the in vitro gender-specific partitioning of mefloquine in malarial infected red blood cells and plasma.

    Science.gov (United States)

    Seethorn, Nongluk; Wernsdorfer, Walther H; Noedl, Harald; Karbwang, Juntra; Na-Bangchang, Kesara

    2013-10-01

    The investigation of gender-specific partitioning of the antimalarial drug mefloquine to cellular and fluid blood compartments was performed using blood collected from a female and male healthy subject that were infected with Plasmodium falciparum PCM2 clone and spiked with mefloquine (0.25, 1, and 5 μM). Mefloquine concentrations in red cells of both female and male subjects were significantly higher than plasma, which suggests an intensive uptake by red cells. This was supported by a high ratio of mefloquine concentrations in the parasitized and non-parasitized red cells of about 4-fold. Gender-specific partitioning of mefloquine in parasitized blood was seen only in plasma where significantly higher concentrations were observed in female compared with male plasma. Down-adjusting the therapeutic dose of mefloquine in female patients with malaria is not advisable because mefloquine concentrations in the target cellular compartment are similar in both genders.

  10. Molecular Dynamics Simulation of Soft Grains: Malaria-Infected Red Blood Cells Motion within Obstructed 2-D Capillary Vessel

    CERN Document Server

    Haris, Luman; Haryanto, Freddy; Viridi, Sparisoma

    2013-01-01

    Molecular dynamics has been widely used to numerically solve equation of motion of classical many-particle system. It can be used to simulate many systems including biophysics, whose complexity level is determined by the involved elements. Based on this method, a numerical model had been constructed to mimic the behaviour of malaria-infected red blood cells within capillary vessel. The model was governed by three forces namely Coulomb force, normal force, and Stokes force. By utilizing two dimensional four-cells scheme, theoretical observation was carried out to test its capability. Although the parameters were chosen deliberately, all of the quantities were given arbitrary value. Despite this fact, the results were quite satisfactory. Combined with the previous results, it can be said that the proposed model were sufficient enough to mimic the malaria-infected red blood cells motion within obstructed capillary vessel. Keywords: molecular dynamics, two-dimensional model, red-blood cell motion, malaria

  11. Long-term effects on the histology and function of livers and spleens in rats after 33% toploading of PEG-PLA-nano artificial red blood cells.

    Science.gov (United States)

    Liu, Zun Chang; Chang, Thomas M S

    2008-01-01

    This study is to investigate the long-term effects of nanodimension PEG-PLA artificial red blood cells containing hemoglobin and red blood cell enzymes on the liver and spleen after 1/3 blood volume top loading in rats. The experimental rats received one of the following infusions: Nano artificial red blood cells in Ringer lactate, Ringer lactate, stroma-free hemoglobin, polyhemoglobin, and autologous rat whole blood. Blood samples were taken before infusions and on days 1, 7, and 21 after infusions for analysis. Nano artificial red blood cells, polyhemoglobin, Ringer lactate and rat red blood cells did not have any significant adverse effects on alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, creatine kinase, amylase and creatine kinase. On the other hand, stroma-free hemoglobin induced significant adverse effects on liver as shown by elevation in alanine aminotransferase and aspartate aminotransferase throughout the 21 days. On day 21 after infusions rats were sacrificed and livers and spleens were excised for histological examination. Nano artificial red blood cells, polyhemoglobin, Ringer lactate and rat red blood cells did not cause any abnormalities in the microscopic histology of the livers and spleens. In the stroma-free hemoglobin group the livers showed accumulation of hemoglobin in central veins and sinusoids, and hepatic steatosis. In conclusion, injected nano artificial red blood cells can be efficiently metabolized and removed by the reticuloendothelial system, and do not have any biochemical or histological adverse effects on the livers or the spleens.

  12. Development and application of resistive pulse spectroscopy: studies on the size, form and deformability of red blood cells

    Energy Technology Data Exchange (ETDEWEB)

    Yee, J.P.

    1979-01-01

    The following studies were conducted using the resistive pulse spectroscopy (RPS) technique: cumulative spectra and individual pulse forms for rigid latex polymer spheres; acquisition and analysis of RPS spectral data by means of special computer program; interaction of red blood cells with glutaraldehyde; membrane properties of erythrocytes undergoing abrupt osmotic hemolysis; reversible effects of the binding of chlorpromazine HCl at the red cell membrane surface; effects of high cholesterol diet on erythrocytes of guinea pigs; and multi-population analysis for a mixture of fetal and maternal red cells. (HLW)

  13. THE EFFECTS OF OXIMES IN THE ASSAY OF ACETYLCHOLINESTERASE ACTIVITY IN LYSED ERYTHROCYTES IN VITRO

    Directory of Open Access Journals (Sweden)

    M. Abdollahi.

    1997-06-01

    Full Text Available Organophosphorus compounds are known to inhibit the esteratic site of acetylcholinesterase by phosphorylation. The phosphorylated esteratic site of acetylcholinesterase undergoes hydrolytic regeneration at a slow or negligible rate. Nucleophilic agents such as hydroxytamine, hydroxamic acids, and oximes reactivate the enzyme more erapidfy than does spontaneous hydrolysis. The red cell cholinesterose activity was assayed using dithio bis-2-nitrobenzoic acid (DTNB commonly known as Ellman's reagent. The principle of this assay method is the rate of hydrolysis of acetylthiocholine (substrate by a red celt suspension. Thiocholine that is produced, forms a yellow complex, when EUman's reagent (DTNB is used in the assay. This was tested in vitro in lysed erythrocyte samples of 35 healthy persons who had no known exposure to cholinesterose inhibitors, after the observation of immediate increase in absorption of light at 440 nm. All of data were statistically analyzed using one-way ANOVA and student t-test. A value of p<0.01 was considered. Results of this study show an increased absorbance in 440 nm, for pretreated samples with pratidoxime. This was observed by doses of (0.1, 0.5, 1,2 mmol, p<0.01. It was also a good dose dependent increase in absorbance at 440 nm for pralidoxime, (r=0.940, p<0.01. Also there is a significant increase in absorbance at 440 nm for samples pretreated by obidoxime at doses of (0.1, 0.5, 1,2 mmol. There is also a good correlation between absorbance at 440 nm and variou doses of obidoxime (r=0.946 , p<0.01. It is concluded that oximes can hydrofyzes the substrate, which then would be a source of error in determination of acetylcholinesterase activity and must be token into account.

  14. Blood serum and BSA, but neither red blood cells nor hemoglobin can support vitellogenesis and egg production in the dengue vector Aedes aegypti

    Directory of Open Access Journals (Sweden)

    Kristina K. Gonzales

    2015-05-01

    Full Text Available 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.

  15. Effect of an Arctium lappa (burdock) extract on the labeling of blood constituents with technetium-99m and on the morphology of the red blood cells

    Energy Technology Data Exchange (ETDEWEB)

    Neves, Rosane de Figueiredo; Rebello, Bernardo Machado; Medeiros, Aldo da Cunha [Universidade Federal do Rio Grande do Norte, Natal, RN (Brazil). Programa de Pos-graduacao em Ciencias da Saude]. E-mail: nevesrosane@yahoo.com.br; Moreno, Silvana Ramos Farias; Fonseca, Adenilson de Souza da [Universidade do Estado do Rio de Janeiro (UERJ), RJ (Brazil). Inst. de Biologia Roberto Alcantara Gomes. Lab. de Radiofarmacia Experimental; Caldas, Luiz Querino de Araujo [Universidade Federal Fluminense, Niteroi, RJ (Brazil). Programa de Pos-Graduacao em Ciencias Medicas; Bernardo-Filho, Mario [Instituto Nacional do Cancer (INCa), Rio de Janeiro, RJ (Brazil). Coordenadoria de Pesquisa

    2007-09-15

    Arctium lappa (burdock) has been used to treat inflammatory processes. Blood constituents labeled with technetium-99m ({sup 99m}Tc) have been utilized in nuclear medicine. It was evaluated the influence of a burdock extract on the labeling of blood constituents with {sup 99m}Tc and on the morphometry of red blood cells. Blood samples from Wistar rats were incubated with burdock extract and the radiolabeling procedure was carried out. Plasma and blood cells, soluble and insoluble fractions of plasma and blood cells were separated. The radioactivity in each fraction was counted and the percentages of radioactivity (%ATI) were determined. Morphology and morphometric (perimeter/area ratio) measurements of red blood cells (RBC) were performed. The incubation with burdock extract significantly (p<0.05) altered the %ATI on the blood compartments and the perimeter/area ratio of RBC, as well as, induced modifications on the shape of RBC. Alterations on membrane could justify the decrease of labeling of blood cells with {sup 99m}Tc obtained in this study. (author)

  16. Increased rigidity of red blood cell membrane in young spontaneously hypertensive rats.

    Science.gov (United States)

    Chabanel, A; Schachter, D; Chien, S

    1987-12-01

    The micropipette test was used to study the effects of age on the elasticity of red blood cell (RBC) membrane in spontaneously hypertensive rats (SHR) and age-matched normotensive Wistar-Kyoto rats (WKY), ranging from 3 to 23 weeks of age. The development of hypertension in the SHR started at 3 weeks and was fully established at 7 to 8 weeks. In the developmental phase of hypertension (3-5 weeks), the SHR showed a significant increase in RBC membrane elastic modulus (i.e., a decrease in RBC membrane deformability) when compared with the age-matched normotensive control rats (WKY). After the establishment of hypertension (7-8 weeks), however, the deformability of the RBC membrane of SHR improved and became comparable to that of the WKY. These results indicate that abnormal erythrocyte membrane elasticity is an early event in SHR and that adaptive recovery occurs when hypertension is fully developed.

  17. Comparison of red blood cells from gastric cancer patients and healthy persons using FTIR spectroscopy

    Science.gov (United States)

    Liu, Hui; Su, Qinglong; Sheng, Daping; Zheng, Wei; Wang, Xin

    2017-02-01

    In this paper, FTIR spectroscopy was used to compare gastric cancer patients' red blood cells (RBCs) with healthy persons' RBCs. IR spectra were acquired with high resolution. The A1653/A1543 (the protein secondary structures), A1543/A2958 (the relative content of proteins and lipids), A1106/A1166 (the structure and content changes of sugars) and A1543/A1106 (the relative content of proteins and sugars) ratios of gastric cancer patients' RBCs were significantly different from those of healthy persons' RBCs. Curve fitting results showed that the protein secondary structures and sugars' structures had differences between gastric cancer patients' and healthy persons' RBCs. Additionally, FTIR spectroscopy could obtain 95% sensitivity, 70% specificity, 84.2% accuracy and 80.9% positive predictive value in combination with canconical discriminant analysis. The above results indicate FTIR spectroscopy may be useful for diagnosing gastric cancer.

  18. On the birefringence of healthy and malaria-infected red blood cells

    CERN Document Server

    Dharmadhikari, Aditya K; Dharmadhikari, Jayashree A; Sharma, Shobhona; Mathur, Deepak

    2013-01-01

    We have probed how the birefringence of a healthy red blood cell (RBC) changes as it becomes infected by a malarial parasite. By analyzing the polarization properties of light transmitted through a single, optically-trapped cell we demarcate two types of birefringence: form birefringence which depends on the shape of the cell and intrinsic birefringence which is brought about by the presence of the parasite. We quantitatively measure changes in the refractive index as normal RBS become infected by a malarial parasite. Malarial infections are found to induce changes in the cell's refractive index whose magnitude depends on the stage of malarial infection; such changes were quantitatively explored and found to be large, in the range 1.2 to 3$\\times10^{-2}$. Our results have implications for the development and use of non-invasive techniques that seek to quantify changes in cell properties induced by pathological states accompanying diseases like malaria. From a broader prespective, information forthcoming from ...

  19. Integrated quantitative phase and birefringence microscopy for imaging malaria-infected red blood cells

    Science.gov (United States)

    Li, Chengshuai; Chen, Shichao; Klemba, Michael; Zhu, Yizheng

    2016-09-01

    A dual-modality birefringence/phase imaging system is presented. The system features a crystal retarder that provides polarization mixing and generates two interferometric carrier waves in a single signal spectrum. The retardation and orientation of sample birefringence can then be measured simultaneously based on spectral multiplexing interferometry. Further, with the addition of a Nomarski prism, the same setup can be used for quantitative differential interference contrast (DIC) imaging. Sample phase can then be obtained with two-dimensional integration. In addition, birefringence-induced phase error can be corrected using the birefringence data. This dual-modality approach is analyzed theoretically with Jones calculus and validated experimentally with malaria-infected red blood cells. The system generates not only corrected DIC and phase images, but a birefringence map that highlights the distribution of hemozoin crystals.

  20. Raman Tweezers Spectroscopy of Live, Single Red and White Blood Cells

    Science.gov (United States)

    Bankapur, Aseefhali; Zachariah, Elsa; Chidangil, Santhosh; Valiathan, Manna; Mathur, Deepak

    2010-01-01

    An optical trap has been combined with a Raman spectrometer to make high-resolution measurements of Raman spectra of optically-immobilized, single, live red (RBC) and white blood cells (WBC) under physiological conditions. Tightly-focused, near infrared wavelength light (1064 nm) is utilized for trapping of single cells and 785 nm light is used for Raman excitation at low levels of incident power (few mW). Raman spectra of RBC recorded using this high-sensitivity, dual-wavelength apparatus has enabled identification of several additional lines; the hitherto-unreported lines originate purely from hemoglobin molecules. Raman spectra of single granulocytes and lymphocytes are interpreted on the basis of standard protein and nucleic acid vibrational spectroscopy data. The richness of the measured spectrum illustrates that Raman studies of live cells in suspension are more informative than conventional micro-Raman studies where the cells are chemically bound to a glass cover slip. PMID:20454686