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Sample records for packed red cell

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

    PubMed

    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.

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

    PubMed

    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. PMID:24611298

  3. Reduction of prion infectivity in packed red blood cells

    SciTech Connect

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

    2008-12-12

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

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

    SciTech Connect

    Thorp, J.A.; Plapp, F.V.; Cohen, G.R.; Yeast, J.D.; O'Kell, R.T.; Stephenson, S. )

    1990-08-01

    Plasma potassium, calcium, and albumin concentrations in irradiated blood, and in fetal blood before and after transfusion, were measured. Dangerously high plasma potassium levels were observed in some units of irradiated packed red blood cells (range, 13.9 to 66.5 mEq/L; mean, 44.7 mEq/L) and could be one possible explanation for the high incidence of fetal arrhythmia associated with fetal intravascular transfusion. There are many factors operative in the preparation of irradiated packed red blood cells that may predispose to high potassium levels: the age of the red blood cells, the number of procedures used to concentrate the blood, the duration of time elapsed from concentration, the duration of time elapsed from irradiation, and the hematocrit. Use of fresh blood, avoidance of multiple packing procedures, limiting the hematocrit in the donor unit to less than or equal to 80%, and minimizing the time between concentration, irradiation and transfusion may minimize the potassium levels, and therefore making an additional washing procedure unnecessary.

  5. Evaluation of the pneumatic tube system for transportation of packed red cell units

    PubMed Central

    Dhar, Supriya; Basu, Sabita; Chakraborty, Subhosmito; Sinha, Subir

    2015-01-01

    Background: Pneumatic tube system (PTS) is commonly used in hospital settings to transport blood samples to diagnostic laboratories. At our blood center, we receive blood requisitions via the PTS, but units are carried to the ward by human courier. Recently we considered using the PTS for transporting blood units. Since, there are reports of hemolysis in blood samples sent through the PTS, we evaluated this system for transporting red cell units. Aims: The aim was to assess the effect of PTS transport on the quality of packed red cell units. Materials and Methods: A total of 50 red blood cells units (RBC), (25 non-irradiated and 25 irradiated) were subjected to transportation through the PTS. The control arm in the study was age-matched RBC units not subjected to PTS transport. Each RBC unit was evaluated for hemoglobin (Hb), lactate dehydrogenase, potassium and plasma hemoglobin (Hb). The paired t-test was used to compare these parameters, and the P value was calculated. Results and Conclusion: The percentage of hemolysis after transportation through PTS was below the recommended guidelines. Delivery of the blood unit to the wrong station, bags lying unattended at the destination were few of the problems that had to be addressed. To conclude, though the PTS is a safe means of transporting blood products with reduction in the turn-around-time, it must be validated before use. PMID:26420944

  6. Nanodefects of membranes cause destruction of packed red blood cells during long-term storage.

    PubMed

    Kozlova, Еlena; Chernysh, Аleksandr; Moroz, Victor; Sergunova, Victoria; Gudkova, Оlga; Kuzovlev, Аrtem

    2015-10-01

    Packed red blood cells (PRBC) are used for blood transfusion. PRBC were stored for 30 days under 4 °С in hermetic blood bags with CPD anticoagulant-preservative solution. Hematocrit was 50-55%. The distortions of PRBC membranes nanostructure and cells morphology during storage were studied by atomic force microscopy. Basic measurements were performed at the day 2, 6, 9, 16, 23 and 30 of storage and additionally 2-3 days after it. Topological defects occurred on RBC membranes by day 9. They appeared as domains with grain-like structures ("grains") sized up to 200 nm. These domains were appeared in almost all cells. Later these domains merged and formed large defects on cells. It was the formation of domains with the "grains" which was onset process leading eventually to destruction of PRBC. Possible mechanisms of transformation of PRBC and their membrane are related to the alterations of spectrin cytoskeleton. During this storage period potassium ions and lactat concentrations increased, pH decreased, intracellular concentration of reduced glutathione diminished in the preservative solution. Changes of PRBC morphology were detected within the entire period of PRBC storage. Discocytes predominated at the days 1 and 2. By day 30 PRBC transformed into irreversible echinocytes and spheroechinocytes. Study of defects of membranes nanostructure may form the basis of assessing the quality of the stored PRBC. This method may allow to work out the best recommendations for blood transfusion.

  7. Time Dependent Assessment of Morphological Changes: Leukodepleted Packed Red Blood Cells Stored in SAGM

    PubMed Central

    2016-01-01

    Usually packed red blood cells (pRBCs) require specific conditions in storage procedures to ensure the maximum shelf life of up to 42 days in 2–6°C. However, molecular and biochemical consequences can affect the stored blood cells; these changes are collectively labeled as storage lesions. In this study, the effect of prolonged storage was assessed through investigating morphological changes and evaluating oxidative stress. Samples from leukodepleted pRBC in SAGM stored at 4°C for 42 days were withdrawn aseptically on day 0, day 14, day 28, and day 42. Morphological changes were observed using scanning electron microscopy and correlated with osmotic fragility and hematocrit. Oxidative injury was studied through assessing MDA level as a marker for lipid peroxidation. Osmotic fragility test showed that extended storage time caused increase in the osmotic fragility. The hematocrit increased by 6.6% from day 0 to day 42. The last 2 weeks show alteration in the morphology with the appearance of echinocytes and spherocytes. Storage lesions and morphological alterations appeared to affect RBCs during the storage period. Further studies should be performed to develop strategies that will aid in the improvement of stored pRBC quality and efficacy. PMID:26904677

  8. Nanodefects of membranes cause destruction of packed red blood cells during long-term storage

    SciTech Connect

    Kozlova, Elena; Chernysh, Aleksandr; Moroz, Victor; Sergunova, Victoria; Gudkova, Olga; Kuzovlev, Artem

    2015-10-01

    Packed red blood cells (PRBC) are used for blood transfusion. PRBC were stored for 30 days under 4 °C in hermetic blood bags with CPD anticoagulant-preservative solution. Hematocrit was 50–55%. The distortions of PRBC membranes nanostructure and cells morphology during storage were studied by atomic force microscopy. Basic measurements were performed at the day 2, 6, 9, 16, 23 and 30 of storage and additionally 2–3 days after it. Topological defects occurred on RBC membranes by day 9. They appeared as domains with grain-like structures (“grains”) sized up to 200 nm. These domains were appeared in almost all cells. Later these domains merged and formed large defects on cells. It was the formation of domains with the “grains” which was onset process leading eventually to destruction of PRBC. Possible mechanisms of transformation of PRBC and their membrane are related to the alterations of spectrin cytoskeleton. During this storage period potassium ions and lactat concentrations increased, pH decreased, intracellular concentration of reduced glutathione diminished in the preservative solution. Changes of PRBC morphology were detected within the entire period of PRBC storage. Discocytes predominated at the days 1 and 2. By day 30 PRBC transformed into irreversible echinocytes and spheroechinocytes. Study of defects of membranes nanostructure may form the basis of assessing the quality of the stored PRBC. This method may allow to work out the best recommendations for blood transfusion. - Highlights: • Domains with “grains” are formed on membranes surface on 9–16 days of PRBC storage. • The development of domains is the reason of irreversible changes of PRBC structure. • The origin of domains is the consequence of alterations of spectrin cytoskeleton. • Study of nanostructure may form basis of assessing the quality of the stored PRBC.

  9. Packed Red Blood Cells Are an Abundant and Proximate Potential Source of Nitric Oxide Synthase Inhibition

    PubMed Central

    Zwemer, Charles F.; Davenport, Robertson D.; Gomez-Espina, Juan; Blanco-Gonzalez, Elisa; Whitesall, Steven E.; D'Alecy, Louis G.

    2015-01-01

    Objective 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). Background 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. Methods 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. Results 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. Conclusion 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

  10. Intraoperative transfusion of packed red blood cells in microvascular free tissue transfer patients: assessment of 30-day morbidity using the NSQIP dataset.

    PubMed

    Kim, Bobby D; Ver Halen, Jon P; Mlodinow, Alexei S; Kim, John Y S

    2014-02-01

    Although often a life-saving therapeutic maneuver, there is minimal data available that details the effects of intraoperative packed red blood cell transfusion (IOT) after microvascular free tissue transfer. The National Surgical Quality Improvement Program database was queried to identify all patients who underwent microvascular free tissue transfer between 2006 and 2010. Multivariate logistic regression models were used to determine the association between intraoperative transfusion and outcomes. Upon bivariate and multivariate analyses, IOT was significantly associated with higher rates of overall complications (odds ratio [OR], 2.02; 95% confidence interval [CI], 1.12-3.63), medical complications (OR, 3.35; 95% CI, 1.75-6.42), postoperative transfusion (OR, 6.02; 95% CI, 2.02-17.97), and reoperation (OR, 2.24; 95% CI, 1.24-4.04). IOT was not associated with either surgical complications or free flap loss. IOT significantly increases risk for adverse overall and medical complications. However, IOT was not associated with surgical complications or free flap loss. Transfusion practices in the operating room should be reevaluated to improve overall outcomes.

  11. Haemostatic profile of reconstituted blood in a proposed 1:1:1 ratio of packed red blood cells, platelet concentrate and four different plasma preparations.

    PubMed

    Ponschab, M; Schöchl, H; Gabriel, C; Süssner, S; Cadamuro, J; Haschke-Becher, E; Gratz, J; Zipperle, J; Redl, H; Schlimp, C J

    2015-05-01

    The concept of haemostatic resuscitation implies early and high-volume plasma transfusion. We investigated the haemostatic profile of reconstituted whole blood prepared in a 1:1:1 ratio of blood, platelets and plasma. This consisted of packed red blood cells, platelet concentrate and four different plasma variants: fresh frozen; solvent-detergent; lyophilised quarantine; and lyophilised methylene blue-inactivated plasma. Haematocrit, platelet count, endogenous thrombin potential and coagulation factor activity were significantly lower in reconstituted blood compared with citrated whole blood (p < 0.01). Except for lyophilised methylene blue-inactivated plasma, no substantial differences between plasma variants in coagulation factor activity, endogenous thrombin potential and standard coagulation tests were observed. After reconstitution, haematocrit and platelet counts were slightly above recommended transfusion triggers, most thromboelastometry (ROTEM(®)) parameters were within the normal range and fibrinogen concentrations were between 1.57 g.l(-1) and 1.91 g.l(-1). Reconstitution of whole blood in a 1:1:1 ratio resulted in significant dilution of haematocrit and platelet count, but values remained above limits recommended by transfusion guidelines. Fibrinogen concentrations of reconstituted whole blood were also significantly reduced, and these were below the threshold value for supplementation recommended by recent guidelines.

  12. Quality, Stability, and Safety Data of Packed Red Cells and Plasma Processed by Gravity Separation Using a New Fully Integrated Hollow-Fibre Filter Device

    PubMed Central

    Brune, T.; Hannemann-Pohl, K.; Nißle, K.; Ecker, N.; Garritsen, H.

    2009-01-01

    Background. We developed a completely closed system based on gravity separation without centrifugation steps for separation of whole blood. With this new system we compared quality and stability of the processed blood components (PRC and plasma) with respect to classical preparation. Furthermore the cost-effectiveness of this hollow fibre system was evaluated. Study Design and Methods. Whole blood collections of 15 regular blood donors were used for component preparation using the U shaped hollow fibre filter device. Results were compared to 15 whole blood preparations using centrifugation. The following parameters were evaluated: total hemoglobin, leukocyte counts, the serum concentration of total protein, lactate dehydrogenase (LDH) and potassium. Furthermore ATIII, vWF and F VIII were analyzed at different timepoints. Results. packed red cells: the data directly after separation and after 42 days of storage are in line with the guidelines of the council of Europe. Plasma. all plasma quality data are in line with the guidelines of the council of Europe for quality assurance of plasma, except for a low protein amount (factor 0.75). Conclusion. Separation of whole blood on a clinical scale in this new closed system is feasible, however the plasma protein content must be optimized. PMID:20169121

  13. Red blood cell production

    MedlinePlus

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

  14. Decolorization of Congo Red with three-dimensional flow-by packed-bed electrodes.

    PubMed

    Wang, Chih-Ta

    2003-02-01

    The electrochemical removal of the color of the dyestuff Congo Red was investigated experimentally by using packed graphite anodes as well as packed graphite or C-304 stainless steel cathodes in an undivided reactor. The effects of the applied apparent current density, the amount of chloride ion addition, the pH value of the solution, the cathode material, the operating temperature, the volumetric flow rate and the initial concentration of Congo Red on the removal efficiencies were investigated in this study. Experimental results showed that the main pathway of color removal was by the hypochlorite generated in-situ at the anodes. Compared with the indirect oxidation, the color removal due to direct oxidation was insignificant. Cathodic oxidation by using graphite cathodes had little influence on the removal rate in an undivided electrochemical cell. PMID:12638704

  15. Red cell enzymes.

    PubMed

    Paniker, N V

    1975-03-01

    As compared to other cells of the body, the mammalian red cell has one of the simplest structural organizations. As a result, this cell has been extensively used in studies involving the structure, function, and integrity of cell membranes as well as cytoplasmic events. Additionally, the metabolic activities of the red blood cell are also relatively simple. During the past quarter century or so, an ocean of knowledge has been gathered on various aspects of red cell metabolism and function. The fields of enzymes, hemoglobin, membrane, and metabolic products comprise the major portion of this knowledge. These advances have made valuable contributions to biochemistry and medicine. Despite these favorable aspects of this simple, anucleated cell, it must be conceded that our knowledge about the red cell is far from complete. We are still in the dark concerning the mechanism involved in several aspects of its membrane, hemoglobin, enzymes, and a large number of other constituents. For example, a large number of enzymes with known catalytic activity but with unknown function have eluded investigators despite active pursuit. This review will be a consolidation of our present knowledge of human red cell enzymes, with particular reference to their usefulness in the diagnosis and therapy of disease. Owing to the multitude of publications by prominent investigators on each of the approximately 50 enzymes discussed in this review, it was impossible to cite a majority of them.

  16. Effect of leukoreduction on concentrations of interleukin-8, interleukin-1β, and tumor necrosis factor-α in canine packed red blood cells during storage.

    PubMed

    Purcell, Sarah L; Claus, Melissa; Hosgood, Giselle; Smart, Lisa

    2015-11-01

    OBJECTIVE To measure changes in interleukin-8 (IL-8), interleukin-1β (IL-1β), and tumor necrosis factor-α (TNF-α) concentrations in stored canine packed RBCs (PRBCs) over time and assess the effect of leukoreduction on these cytokine concentrations. ANIMALS 12 anesthetized healthy Greyhounds. PROCEDURES 1 unit of whole blood from each dog was processed into PRBCs. Half of each PRBCs unit was passed through a leukoreduction filter to produce a leukoreduced unit, and the remaining blood was kept as a nonleukoreduced unit. All units had a CBC performed on day 0 (day of collection) and were stored at 2° to 6°C. Samples were collected from leukoreduced and nonleukoreduced units on days 0, 10, 20, 30, and 37 and centrifuged; the supernatant was stored at -80°C until analysis. Canine TNF-α and IL-8 concentrations were assessed with a multiplexed genomic and proteomic biomarker analyzer, and canine IL-1β concentration was measured by ELISA. RESULTS Leukocyte counts were decreased by ≥ 99.9% in all leukoreduced units. Median TNF-α and IL-1β concentrations were not significantly different between leukoreduced and nonleukoreduced units and did not change significantly during storage; median IL-8 concentration was significantly higher in nonleukoreduced versus leukoreduced units on all days, and was greater at all time points after ≥ 10 days of storage than on day 0. Median IL-8 concentration in leukoreduced units did not increase during storage. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that leukoreduction was effective for the removal of leukocytes from canine PRBCs and prevented significant increases in IL-8 concentration during storage. Further studies are needed to evaluate whether leukoreduction reduces cytokine-associated complications of transfusion.

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

    MedlinePlus

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

  18. Red Cell Membrane Permeability Deduced from Bulk Diffusion Coefficients

    PubMed Central

    Redwood, W. R.; Rall, E.; Perl, W.

    1974-01-01

    The permeability coefficients of dog red cell membrane to tritiated water and to a series of[14C]amides have been deduced from bulk diffusion measurements through a "tissue" composed of packed red cells. Red cells were packed by centrifugation inside polyethylene tubing. The red cell column was pulsed at one end with radiolabeled solute and diffusion was allowed to proceed for several hours. The distribution of radioactivity along the red cell column was measured by sequential slicing and counting, and the diffusion coefficient was determined by a simple plotting technique, assuming a one-dimensional diffusional model. In order to derive the red cell membrane permeability coefficient from the bulk diffusion coefficient, the red cells were assumed to be packed in a regular manner approximating closely spaced parallelopipeds. The local steady-state diffusional flux was idealized as a one-dimensional intracellular pathway in parallel with a one-dimensional extracellular pathway with solute exchange occurring within the series pathway and between the pathways. The diffusion coefficients in the intracellular and extracellular pathways were estimated from bulk diffusion measurements through concentrated hemoglobin solutions and plasma, respectively; while the volume of the extracellular pathway was determined using radiolabeled sucrose. The membrane permeability coefficients were in satisfactory agreement with the data of Sha'afi, R. I., C. M. Gary-Bobo, and A. K. Solomon (1971. J. Gen. Physiol. 58:238) obtained by a rapid-reaction technique. The method is simple and particularly well suited for rapidly permeating solutes. PMID:4443795

  19. Red cell aging in vivo

    PubMed Central

    Ganzoni, A. M.; Oakes, R.; Hillman, R. S.

    1971-01-01

    Previous studies of red cell structure and metabolism during the aging process have relied upon in vitro techniques of cell separation into various age populations. Probably the most common approach is to isolate the older red cells with the assumption that they are more dense. This may lead to a number of inconsistencies in observations, and may certainly raise questions about possible cell changes secondary to manipulative procedures. For this reason, an experimental system was devised where a normal red cell population could be studied, while aging, in an in vivo environment. The initial red cell mass of a large number of inbred rats was transferred repeatedly into an ever smaller number of animals, making it possible to follow an aging population of red cells up to 48 days while preventing contamination with newly produced cells by suppression of erythropoiesis with transfusion-induced polycythemia. During this period, samples of progressively older red cells could be obtained for measurements of red cell constant. It was noted that the normal rat red cell undergoes both volume reduction and significant hemoglobin content loss with aging. In addition, the hemoglobin concentration within the cell demonstrated an early rise after a return to nearly normal values. These findings are noteworthy in that they help to explain the characteristics of life-spans of cohort labeled red cell populations in small animals, and provide a possible example of a cell's remodeling process within the spleen. PMID:5090053

  20. Red blood cells, sickle cell (image)

    MedlinePlus

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

  1. Red cell metabolism in red and grey kangaroos.

    PubMed

    Agar, N S

    1977-12-15

    Glucose utilization, lactate production and glutathione regeneration were measured in the red blood cells of 2 species of Australian Marsupials, Eastern grey Kangaroo (Macropus gigantus) and red kangaroo (Macropus rufus), and were found to be significantly lower in the red blood cells from grey than that of red kangaroos.

  2. Red blood cell morphology.

    PubMed

    Ford, J

    2013-06-01

    The foundation of laboratory hematologic diagnosis is the complete blood count and review of the peripheral smear. In patients with anemia, the peripheral smear permits interpretation of diagnostically significant red blood cell (RBC) findings. These include assessment of RBC shape, size, color, inclusions, and arrangement. Abnormalities of RBC shape and other RBC features can provide key information in establishing a differential diagnosis. In patients with microcytic anemia, RBC morphology can increase or decrease the diagnostic likelihood of thalassemia. In normocytic anemias, morphology can assist in differentiating among blood loss, marrow failure, and hemolysis-and in hemolysis, RBC findings can suggest specific etiologies. In macrocytic anemias, RBC morphology can help guide the diagnostic considerations to either megaloblastic or nonmegaloblastic causes. Like all laboratory tests, RBC morphologies must be interpreted with caution, particularly in infants and children. When used properly, RBC morphology can be a key tool for laboratory hematology professionals to recommend appropriate clinical and laboratory follow-up and to select the best tests for definitive diagnosis. PMID:23480230

  3. Red blood cell morphology.

    PubMed

    Ford, J

    2013-06-01

    The foundation of laboratory hematologic diagnosis is the complete blood count and review of the peripheral smear. In patients with anemia, the peripheral smear permits interpretation of diagnostically significant red blood cell (RBC) findings. These include assessment of RBC shape, size, color, inclusions, and arrangement. Abnormalities of RBC shape and other RBC features can provide key information in establishing a differential diagnosis. In patients with microcytic anemia, RBC morphology can increase or decrease the diagnostic likelihood of thalassemia. In normocytic anemias, morphology can assist in differentiating among blood loss, marrow failure, and hemolysis-and in hemolysis, RBC findings can suggest specific etiologies. In macrocytic anemias, RBC morphology can help guide the diagnostic considerations to either megaloblastic or nonmegaloblastic causes. Like all laboratory tests, RBC morphologies must be interpreted with caution, particularly in infants and children. When used properly, RBC morphology can be a key tool for laboratory hematology professionals to recommend appropriate clinical and laboratory follow-up and to select the best tests for definitive diagnosis.

  4. Red blood cells, sickle cells (image)

    MedlinePlus

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

  5. Red blood cells, spherocytosis (image)

    MedlinePlus

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

  6. Red Blood Cell Antibody Identification

    MedlinePlus

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

  7. Non-universal Voronoi cell shapes in amorphous ellipsoid packs

    NASA Astrophysics Data System (ADS)

    Schaller, Fabian M.; Kapfer, Sebastian C.; Hilton, James E.; Cleary, Paul W.; Mecke, Klaus; De Michele, Cristiano; Schilling, Tanja; Saadatfar, Mohammad; Schröter, Matthias; Delaney, Gary W.; Schröder-Turk, Gerd E.

    2015-07-01

    In particulate systems with short-range interactions, such as granular matter or simple fluids, local structure determines the macroscopic physical properties. We analyse local structure metrics derived from the Voronoi diagram of oblate ellipsoids, for various aspect ratios α and global packing fractions φ\\text{g} . We focus on jammed static configurations of frictional ellipsoids, obtained by tomographic imaging and by discrete element method simulations. The rescaled distribution of local packing fractions φ\\text{l} , defined as the ratio of particle volume and its Voronoi cell volume, is found to be independent of the particle aspect ratio, and coincide with results for sphere packs. By contrast, the typical Voronoi cell shape, quantified by the Minkowski tensor anisotropy index β=β_02,0 , points towards a difference between random packings of spheres and those of oblate ellipsoids. While the average cell shape β of all cells with a given value of φ\\text{l} is similar in dense and loose jammed sphere packings, the structure of dense and loose ellipsoid packings differs substantially such that this does not hold true.

  8. Red cell metabolism studies on Skylab

    NASA Technical Reports Server (NTRS)

    Mengel, C. E.

    1977-01-01

    Blood samples from Spacelab crewmembers were studied for possible environment effects on red cell components. Analysis involved peroxidation of red cell lipids, enzymes of red cell metabolism, and levels of 2,3-diphosphoglyceric acid and adenosine triphosphate. Results show that there is no evidence of lipid peroxidation, that biochemical effect known to be associated with irreversible red cell damage. Changes observed in glycolytic intermediates and enzymes cannot be directly implicated as indicating evidence of red cell damage.

  9. Iron supplementation, maternal packed cell volume, and fetal growth.

    PubMed Central

    Hemminki, E; Rimpelä, U

    1991-01-01

    Previous studies have found that there is a correlation between mothers' haemoglobin concentration or packed cell volume and infants' birth weight, and that iron supplementation increases mothers' haemoglobin concentration. The purpose of this study, using the data of a large randomised trial on iron prophylaxis during pregnancy, was to find out whether iron supplementation causes fetal growth to deteriorate. At their first antenatal visit, 2912 pregnant women were randomised into non-routine iron and routine iron supplementation. The mean length of gestation was shorter in the non-routine group. Birth weight did not differ between the groups, but due to longer gestations boys in the group receiving routine iron were taller than in the non-routine group. In both groups, whether studied by various values of packed cell volume or correlation coefficients, the lower the packed cell volume, the heavier and taller the infant and heavier the placenta. These negative correlations could be seen even with a packed cell volume measured early in pregnancy. Standardising for blood pressure did not influence the correlation coefficients. The correlation between a high ratio for packed cell volume and poor fetal growth thus may not be caused by iron supplementation, nor mediated by blood pressure, but by some other mechanism. PMID:2025036

  10. Pack aluminization of nickel anode for molten carbonate fuel cells

    NASA Astrophysics Data System (ADS)

    Chun, H. S.; Park, G. P.; Lim, J. H.; Kim, K.; Lee, J. K.; Moon, K. H.; Youn, J. H.

    1994-04-01

    The aluminum pack cementation (pack aluminization) process on a porous nickel anode for molten carbonate fuel cells has been studied to improve anode creep resistance. The porous nickel substrates used in this study were fabricated by doctor blade equipment followed by sintering (850 C). Packs surrounding the Ni anode were made by mixing Al2O3 powder, Al powder, and NaCl as activator. The pack aluminization was performed at 700 to 850 C for 0.5-5.0 h. After pack aluminization, the principal Ni-Al intermetallic compounds detected were Ni3Al at 700 C, NiAl at 750 C and Ni3Al2 at 800 C. The aluminum content in the aluminized Ni anode was proportional to the square root of pack aluminizing time. With increasing the Al content in the anode, the creep of the anode decreased. It was nearly constant (2.0%) when the Al content was above 5.0%. Although the exchange current density (24 mA/sq cm) for the aluminized (2.5 wt.%) Ni anode was somewhat lower than that of the pure Ni anode (40 mA/sq cm), the performance of a single cell using an aluminized Ni anode was similar to that of the one with pure Ni anode.

  11. Kinetic studies on degradation of Reactive Red 120 dye in immobilized packed bed reactor by Bacillus cohnii RAPT1.

    PubMed

    Padmanaban, V C; Geed, Sachin RameshRao; Achary, Anant; Singh, R S

    2016-08-01

    The degradation of Reactive Red 120 using Bacillus cohnii RAPT1 immobilized on polyurethane was studied. Initial experiments indicated that the percentage removal of dye in immobilized batch was significantly higher than batch (without immobilization). The optimum process parameters such as effect of dye concentration, time of immobilization on Poly Urethane Foam, initial inoculum size, pH and temperature for removal of dye were investigated and was found as 200ppm, 36h, 300*10(6) colony forming units/ml, 8.0 and 35°C respectively. Under optimum conditions, 100% removal of dye was obtained within 4h. The kinetics of biodegradation for the batch with free cells and immobilised packed batch was found to be IInd order with kinetic constant and initial rate of reaction as 0.0408, 0.084L/(mgday) and 1632, 3360 (mg/Lday) respectively. PMID:26968121

  12. Effects of helicopter transport on red blood cell components

    PubMed Central

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

    2012-01-01

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

  13. Volatile compounds and odor preferences of ground beef added with garlic and red wine, and irradiated with charcoal pack

    NASA Astrophysics Data System (ADS)

    Lee, Kyung Haeng; Yun, Hyejeong; Lee, Ju Woon; Ahn, Dong Uk; Lee, Eun Joo; Jo, Cheorun

    2012-08-01

    Irradiation is the most efficient non-thermal technology for improving hygienic quality and extending the shelf-life of food products. One of the adverse effects of food irradiation, however, is off-flavor production, which significantly affects the sensory preferences for certain foods. In this study, garlic (5%, w/w) and red wine (1:1, w/w) were added to ground beef to increase the radiation sensitivity of pathogens and improve meat odor/flavor. Samples were irradiated at 0 or 5 kGy in the presence of charcoal pack. SPME-GC-MS analysis was performed to measure the changes in the volatile compounds and sensory characteristics of the samples. The amount of total volatile compounds produced from ground beef was greater when the sample was irradiated. When garlic and red wine were added to the ground beef, the amount of volatile compounds significantly increased, and the amount of volatile compounds increased even further after irradiation. However, when the samples were irradiated with charcoal pack, the amount of volatile compounds decreased significantly. Sensory evaluation indicated that charcoal pack significantly increased the odor preferences for both irradiated and non-irradiated ground beef added with garlic. These results indicated that addition of charcoal pack to ground beef could reduce off-odor problems induced by irradiation, and this effect was consistent even when certain additives such as garlic and red wine were added.

  14. Acquired loss of red cell Kell antigens.

    PubMed

    Vengelen-Tyler, V; Gonzalez, B; Garratty, G; Kruppe, C; Johnson, C L; Mueller, K A; Marsh, W L

    1987-02-01

    A 19-year-old patient with a long history of idiopathic thrombocytopenic purpura developed a potent antibody against a high-incidence antigen in the Kell blood group system. The direct antiglobulin test on his red cells was negative. His cells exhibited profound depression of Kell blood group antigens, but antigens of other blood groups were normal. Transfusion of incompatible blood was well tolerated and differential agglutination tests, using selected Rh antisera, showed in vivo survival of the transfused red cells for more than 8 weeks. However, the transfused red cells also showed acquired loss of Kell antigens. Five months after the initial findings, Kell-related antibody disappeared and Kell antigens reappeared on his red cells. The patient's serum stored from the initial investigation now reacted with his freshly collected red cells. These data suggest that an environmental agent in the patient's plasma was responsible for the temporary loss of Kell antigens from red cells in his circulation.

  15. cellPACK: A Virtual Mesoscope to Model and Visualize Structural Systems Biology

    PubMed Central

    Johnson, Graham T.; Autin, Ludovic; Al-Alusi, Mostafa; Goodsell, David S.; Sanner, Michel F.; Olson, Arthur J.

    2014-01-01

    cellPACK assembles computational models of the biological mesoscale, an intermediate scale (10−7–10−8m) between molecular and cellular biology. cellPACK’s modular architecture unites existing and novel packing algorithms to generate, visualize and analyze comprehensive 3D models of complex biological environments that integrate data from multiple experimental systems biology and structural biology sources. cellPACK is currently available as open source code, with tools for validation of models and with recipes and models for five biological systems: blood plasma, cytoplasm, synaptic vesicles, HIV and a mycoplasma cell. We have applied cellPACK to model distributions of HIV envelope protein to test several hypotheses for consistency with experimental observations. Biologists, educators, and outreach specialists can interact with cellPACK models, develop new recipes and perform packing experiments through scripting and graphical user interfaces at http://cellPACK.org. PMID:25437435

  16. Chemical toxicity of red cells.

    PubMed Central

    Piomelli, S

    1981-01-01

    Exposure to toxic chemicals may result in alterations of red cell function. In certain cases, the toxic effect requires a genetic predisposition and thus affects only a restricted number of individuals; in other instances, the toxic effect is exerted on the hematopoietic system of every person. Glucose-6-phosphate dehydrogenase deficiency is probably the most widespread genetic disorder. It is observed at highest frequency in populations from subtropical countries as a result of its selective advantage vis à vis falciparum malaria. The gene controlling this enzyme is located on the X-chromosome; thus, the defect is sex-linked. Individuals with a genetic defect of this enzyme are extremely susceptible to hemolysis, when exposed to oxidant drugs (such as certain antimalarials and sulfonamides) because of the inability of their red cells to regenerate NADPH. Lead poisoning result in profound effects on the process of heme synthesis. Among the steps most sensitive to lead toxicity are the enzyme delta-aminolevulinic acid dehydratase and the intramitochondrial step that leads to the incorporation of iron into protoporphyrin. By these mechanisms, in severe lead intoxication there is an accumulation of large amounts of delta-aminolevulinic acid (a compound with inherent neurotoxicity), and there are abnormalities of mitochondrial function in all cells of the body. Individuals living in an industrialized society are unavoidably exposed to some environmental lead. Recent evidence indicates that, even at levels of exposure which do not increase the blood lead level above values presently considered normal, abnormalities of heme synthesis are clearly detectable. PMID:7016524

  17. Damage of cells and battery packs due to ground impact

    NASA Astrophysics Data System (ADS)

    Xia, Yong; Wierzbicki, Tomasz; Sahraei, Elham; Zhang, Xiaowei

    2014-12-01

    The present paper documents a comprehensive study on the ground impact of lithium-ion battery packs in electric vehicles. With the purpose of developing generic methodology, a hypothetic global finite element model is adopted. The force-displacement response of indentation process simulated by the global FE model is cross-validated with the earlier analytical solutions. The punching process after the armor plate perforation, the ensuing crack propagation of the armor plate as well as the local deformation modes of individual battery cells are clearly predicted by the global modeling. A parametric study is carried out, and a few underlying rules are revealed, providing important clues on the design of protective structure of battery packs against ground impact. In the next step, detailed FE models at the level of a single battery cell and shell casing are developed and simulations are performed using boundaries and loading conditions taken from the global solution. In the detailed modeling the failure of individual components is taken into account, which is an important indicator of electric short circuit of a battery cell and possible thermal runaway. The damage modes and the deformation tolerances of components in the battery cell under various loading conditions are observed and compared.

  18. Inflight Assay of Red Blood Cell Deformability

    NASA Technical Reports Server (NTRS)

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

    1985-01-01

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

  19. Red blood cell decreases of microgravity

    NASA Technical Reports Server (NTRS)

    Johnson, P. C.

    1985-01-01

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

  20. Frozen red cells in Rhesus immunization.

    PubMed

    Cook, I A; Robb, A L; Mitchell, R; McLaren, E A; Urbaniak, S; Robertson, A E

    1980-04-01

    The use of frozen washed cells in varying doses in primary Rh immunization is compared to two groups of men with the use of fresh washed cells in a third group. In the first two groups, using frozen cells, doses ranging from 0.5 to 20 ml of whole blood (Group I) are compared with a 200.0 ml dose of red cell concentrate (Group II), while Group III served as a control using a 20 ml dose of fresh washed red cell suspension (9.0 ml concentrated red cell equivalent). The response rate was 93% in Group II compared with only 43% in Group I, suggesting the desirability of using relatively large doses of Rh-positive red cells for primary Rh immunization. The use of frozen washed cells from a special panel for 'booster' injections is also recommended.

  1. 21 CFR 640.10 - Red Blood Cells.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

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

  2. 21 CFR 640.10 - Red Blood Cells.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

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

  3. 21 CFR 640.10 - Red Blood Cells.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

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

  4. 21 CFR 640.10 - Red Blood Cells.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

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

  5. 21 CFR 640.10 - Red Blood Cells.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

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

  6. 3D molecular models of whole HIV-1 virions generated with cellPACK

    PubMed Central

    Goodsell, David S.; Autin, Ludovic; Forli, Stefano; Sanner, Michel F.; Olson, Arthur J.

    2014-01-01

    As knowledge of individual biological processes grows, it becomes increasingly useful to frame new findings within their larger biological contexts in order to generate new systems-scale hypotheses. This report highlights two major iterations of a whole virus model of HIV-1, generated with the cellPACK software. cellPACK integrates structural and systems biology data with packing algorithms to assemble comprehensive 3D models of cell-scale structures in molecular detail. This report describes the biological data, modeling parameters and cellPACK methods used to specify and construct editable models for HIV-1. Anticipating that cellPACK interfaces under development will enable researchers from diverse backgrounds to critique and improve the biological models, we discuss how cellPACK can be used as a framework to unify different types of data across all scales of biology. PMID:25253262

  7. Red cell membrane: past, present, and future

    PubMed Central

    Gallagher, Patrick G.

    2008-01-01

    As a result of natural selection driven by severe forms of malaria, 1 in 6 humans in the world, more than 1 billion people, are affected by red cell abnormalities, making them the most common of the inherited disorders. The non-nucleated red cell is unique among human cell type in that the plasma membrane, its only structural component, accounts for all of its diverse antigenic, transport, and mechanical characteristics. Our current concept of the red cell membrane envisions it as a composite structure in which a membrane envelope composed of cholesterol and phospholipids is secured to an elastic network of skeletal proteins via transmembrane proteins. Structural and functional characterization of the many constituents of the red cell membrane, in conjunction with biophysical and physiologic studies, has led to detailed description of the way in which the remarkable mechanical properties and other important characteristics of the red cells arise, and of the manner in which they fail in disease states. Current studies in this very active and exciting field are continuing to produce new and unexpected revelations on the function of the red cell membrane and thus of the cell in health and disease, and shed new light on membrane function in other diverse cell types. PMID:18988878

  8. Avoiding Anemia: Boost Your Red Blood Cells

    MedlinePlus

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

  9. Red cell membrane lipids in hemoglobinopathies.

    PubMed

    Kuypers, Frans A

    2008-11-01

    The complex mixture of lipids and proteins of the red blood cell membrane is well maintained during the life of the cell. Lipid analysis of the red cell reveals hundreds of phospholipid molecular species and cholesterol that differ with respect to their (polar) head group, and (apolar) side chains. These molecules move rapidly in the plane, as well as across the lipid bilayer. This dynamic movement is highly organized. In the plane of the bilayer, areas enriched in certain lipids accommodate protein structure and modulate function. While lipids move across the bilayer, the organization is highly asymmetric. Amino phospholipids are mainly found on the inside and choline containing phospholipids on the outside. Both the composition and organization of the red cell membrane is maintained throughout the life of the red cell by an intricate mechanism that involves enzymes, transporters and cytosolic factors. Key proteins that maintain red blood cell lipid organization have recently been identified. Alterations in these mechanisms, as the result of the globin mutations in sickle cell disease or thalassemia will lead to loss of membrane viability, apoptosis during erythropoiesis, early demise of the cell in the circulation, and when these cells are not removed appropriately their presence has pathologic consequences.

  10. Microstructured multi-well plate for three-dimensional packed cell seeding and hepatocyte cell culture

    PubMed Central

    Goral, Vasiliy N.; Au, Sam H.; Faris, Ronald A.; Yuen, Po Ki

    2014-01-01

    In this article, we present a microstructured multi-well plate for enabling three-dimensional (3D) high density seeding and culture of cells through the use of a standard laboratory centrifuge to promote and maintain 3D tissue-like cellular morphology and cell-specific functionality in vitro without the addition of animal derived or synthetic matrices or coagulants. Each well has microfeatures on the bottom that are comprised of a series of ditches/open microchannels. The dimensions of the microchannels promote and maintain 3D tissue-like cellular morphology and cell-specific functionality in vitro. After cell seeding with a standard pipette, the microstructured multi-well plates were centrifuged to tightly pack cells inside the ditches in order to enhance cell-cell interactions and induce formation of 3D cellular structures during cell culture. Cell-cell interactions were optimized based on cell packing by considering dimensions of the ditches/open microchannels, orientation of the microstructured multi-well plate during centrifugation, cell seeding density, and the centrifugal force and time. With the optimized cell packing conditions, we demonstrated that after 7 days of cell culture, primary human hepatocytes adhered tightly together to form cord-like structures that resembled 3D tissue-like cellular architecture. Importantly, cell membrane polarity was restored without the addition of animal derived or synthetic matrices or coagulants. PMID:25379107

  11. Phosphatidylserine exposure and red cell viability in red cell aging and in hemolytic anemia

    PubMed Central

    Boas, Franz Edward; Forman, Linda; Beutler, Ernest

    1998-01-01

    Phosphatidylserine (PS) normally localizes to the inner leaflet of cell membranes but becomes exposed in abnormal or apoptotic cells, signaling macrophages to ingest them. Along similar lines, it seemed possible that the removal of red cells from circulation because of normal aging or in hemolytic anemias might be triggered by PS exposure. To investigate the role of PS exposure in normal red cell aging, we used N-hydroxysuccinimide-biotin to tag rabbit red cells in vivo, then used phycoerythrin-streptavidin to label the biotinylated cells, and annexin V-fluorescein isothiocyanate (FITC) to detect the exposed PS. Flow cytometric analysis of these cells drawn at 10-day intervals up to 70 days after biotinylation indicated that older, biotinylated cells expose more PS. Furthermore, our data match a simple model of red cell senescence that assumes both an age-dependent destruction of senescent red cells preceded by several hours of PS exposure and a random destruction of red cells without PS exposure. By using this model, we demonstrated that the exposure of PS parallels the rate at which biotinylated red cells are removed from circulation. On the other hand, using an annexin V-FITC label and flow cytometry demonstrates that exposed PS does not cause the reduced red cell life span of patients with hemolytic anemia, with the possible exception of those with unstable hemoglobins or sickle cell anemia. Thus, in some cases PS exposure on the cell surface may signal the removal of red cells from circulation, but in other cases some other signal must trigger the sequestration of cells. PMID:9501218

  12. 21 CFR 864.5300 - Red cell indices device.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Red cell indices device. 864.5300 Section 864.5300....5300 Red cell indices device. (a) Identification. A red cell indices device, usually part of a larger... corpuscular hemoglobin (MCH), and the mean corpuscular hemoglobin concentration (MCHC). The red cell...

  13. 21 CFR 864.8540 - Red cell lysing reagent.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 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...

  14. 21 CFR 864.5300 - Red cell indices device.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Red cell indices device. 864.5300 Section 864.5300....5300 Red cell indices device. (a) Identification. A red cell indices device, usually part of a larger... corpuscular hemoglobin (MCH), and the mean corpuscular hemoglobin concentration (MCHC). The red cell...

  15. 21 CFR 864.8540 - Red cell lysing reagent.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 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...

  16. 21 CFR 864.5300 - Red cell indices device.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Red cell indices device. 864.5300 Section 864.5300....5300 Red cell indices device. (a) Identification. A red cell indices device, usually part of a larger... corpuscular hemoglobin (MCH), and the mean corpuscular hemoglobin concentration (MCHC). The red cell...

  17. 21 CFR 864.8540 - Red cell lysing reagent.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 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...

  18. 21 CFR 864.8540 - Red cell lysing reagent.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 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...

  19. 21 CFR 864.5300 - Red cell indices device.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Red cell indices device. 864.5300 Section 864.5300....5300 Red cell indices device. (a) Identification. A red cell indices device, usually part of a larger... corpuscular hemoglobin (MCH), and the mean corpuscular hemoglobin concentration (MCHC). The red cell...

  20. 21 CFR 864.5300 - Red cell indices device.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Red cell indices device. 864.5300 Section 864.5300....5300 Red cell indices device. (a) Identification. A red cell indices device, usually part of a larger... corpuscular hemoglobin (MCH), and the mean corpuscular hemoglobin concentration (MCHC). The red cell...

  1. 21 CFR 864.8540 - Red cell lysing reagent.

    Code of Federal Regulations, 2010 CFR

    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. Modular Approach for Continuous Cell-Level Balancing to Improve Performance of Large Battery Packs: Preprint

    SciTech Connect

    Muneed ur Rehman, M.; Evzelman, M.; Hathaway, K.; Zane, R.; Plett, G. L.; Smith, K.; Wood, E.; Maksimovic, D.

    2014-10-01

    Energy storage systems require battery cell balancing circuits to avoid divergence of cell state of charge (SOC). A modular approach based on distributed continuous cell-level control is presented that extends the balancing function to higher level pack performance objectives such as improving power capability and increasing pack lifetime. This is achieved by adding DC-DC converters in parallel with cells and using state estimation and control to autonomously bias individual cell SOC and SOC range, forcing healthier cells to be cycled deeper than weaker cells. The result is a pack with improved degradation characteristics and extended lifetime. The modular architecture and control concepts are developed and hardware results are demonstrated for a 91.2-Wh battery pack consisting of four series Li-ion battery cells and four dual active bridge (DAB) bypass DC-DC converters.

  3. Hydrogen peroxide production by red blood cells.

    PubMed

    Giulivi, C; Hochstein, P; Davies, K J

    1994-01-01

    Red blood cells are frequently employed in studies of oxidative stress. Technical difficulties have previously prevented the measurement of H2O2 production by red blood cells, except during exposure to certain drugs or toxicants. We now show that a combination of glutathione depletion and 3-amino-1,2,4-triazole (aminotriazole) treatment can be used to measure the endogenous generation of H2O2 by red blood cells. In our studies, aminotriazole was used as an H2O2 dependent (irreversible) catalase inhibitor, and catalase inhibition was used as an indirect measure of H2O2 production. Our results indicate that H2O2 is generated at a rate of 1.36 +/- 0.2 microM/h (3.9 +/- 0.6 nmol.h-1.g Hb-1), and that the steady-state red blood cell concentration of H2O2 is approximately 2 x 10(-10) M. Kinetic comparisons of H2O2 production and oxyhemoglobin autooxidation (which generates O2.- that dismutases to H2O2) indicate that the latter is probably the main source of H2O2 in red blood cells.

  4. Red cell metabolism studies on Skylab

    NASA Technical Reports Server (NTRS)

    Mengel, C. E.

    1974-01-01

    On the basis of these background data, metabolic studies were performed on humans involved in space flight. These studies included the Skylab experiences. The primary purpose of the investigations was to study red cells for: (1) evidences of lipid peroxidation, or (2) changes at various points in the glycolytic pathway. The Skylab missions were an opportunity to study blood samples before, during, and after flight and to compare results with simultaneous controls. No direct evidence that lipid peroxidation had occurred in the red blood cells was apparent in the studies.

  5. Red blood cell-incompatible allogeneic hematopoietic progenitor cell transplantation.

    PubMed

    Rowley, S D; Donato, M L; Bhattacharyya, P

    2011-09-01

    Transplantation of hematopoietic progenitor cells from red cell-incompatible donors occurs in 30-50% of patients. Immediate and delayed hemolytic transfusion reactions are expected complications of red cell-disparate transplantation and both ABO and other red cell systems such as Kidd and rhesus can be involved. The immunohematological consequences of red cell-incompatible transplantation include delayed red blood cell recovery, pure red cell aplasia and delayed hemolysis from viable lymphocytes carried in the graft ('passenger lymphocytes'). The risks of these reactions, which may be abrupt in onset and fatal, are ameliorated by graft processing and proper blood component support. Red blood cell antigens are expressed on endothelial and epithelial tissues in the body and could serve to increase the risk of GvHD. Mouse models indicate that blood cell antigens may function as minor histocompatibility antigens affecting engraftment. Similar observations have been found in early studies of human transplantation for transfused recipients, although current conditioning and immunosuppressive regimens appear to overcome this affect. No deleterious effects from the use of red cell-incompatible hematopoietic grafts on transplant outcomes, such as granulocyte and platelet engraftments, the incidences of acute or chronic GvHD, relapse risk or OS, have been consistently demonstrated. Most studies, however, include limited number of patients, varying diagnoses and differing treatment regimens, complicating the detection of an effect of ABO-incompatible transplantation. Classification of patients by ABO phenotype ignoring the allelic differences of these antigens also may obscure the effect of red cell-incompatible transplantation on transplant outcomes. PMID:21897398

  6. Metabolic dependence of red cell deformability

    PubMed Central

    Weed, Robert I.; LaCelle, Paul L.; Merrill, Edward W.

    1969-01-01

    The contribution of the metabolic state of human erythrocytes to maintenance of cellular deformability was studied during and after in vitro incubation in serum for periods up to 28 hr. An initial loss of membrane deformability became apparent between 4 and 6 hr when cellular adenosine triphosphate (ATP) levels were approximately 70% of initial values. Membrane deformability then remained stable between 6 and 10 hr. After 10 hr, when cellular ATP had decreased to < 15% of initial values, progressive parallel changes occurred in red cell calcium which increased 400% by 24 hr and in the viscosity of red cell suspensions which had risen 500-750% at 24 hr. A further progressive decrease in membrane deformability also occurred and was reflected by a 1000% increase in negative pressure required to deform the membrane. Red cell filterability decreased to zero as the disc-sphere shape transformation ensued. These changes were accompanied by an increase in ghost residual hemoglobin and nonhemoglobin protein. Regeneration of ATP in depleted cells by incubation with adenosine produced significant reversal of these changes, even in the presence of ouabain. Introduction of calcium into reconstituted ghosts prepared from fresh red cells mimicked the depleted state, and introduction of ATP, ethylenediamine tetraacetate (EDTA), and magnesium into depleted cells mimicked the adenosine effects in intact depleted cells. ATP added externally to 24-hr depleted cells was without effect. Simultaneous introduction of EDTA, ATP, or magnesium along with calcium into reconstituted ghosts prevented the marked decrease in deformability produced by calcium alone. Incorporation of adenosine diphosphate (ADP), nicotinamide adenine dinucleotide (NAD), NAD phosphate (NADP), NADP, reduced form (NADPH), glutatione, reduced form (GSH), inosine triphosphate (ITP), guanosine triphosphate (GTP), and uridine triphosphate (UTP) was without effect. These data suggest that a major role of ATP in maintenance

  7. Viscoelastic Transient of Confined Red Blood Cells

    PubMed Central

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

    2015-01-01

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

  8. Bi-functional biobased packing of the cassava starch, glycerol, licuri nanocellulose and red propolis.

    PubMed

    Costa, Samantha Serra; Druzian, Janice Izabel; Machado, Bruna Aparecida Souza; de Souza, Carolina Oliveira; Guimarães, Alaíse Gil

    2014-01-01

    The aim of this study was to characterize and determine the bi-functional efficacy of active packaging films produced with starch (4%) and glycerol (1.0%), reinforced with cellulose nanocrystals (0-1%) and activated with alcoholic extracts of red propolis (0.4 to 1.0%). The cellulose nanocrystals used in this study were extracted from licuri leaves. The films were characterized using moisture, water-activity analyses and water vapor-permeability tests and were tested regarding their total phenolic compounds and mechanical properties. The antimicrobial and antioxidant efficacy of the films were evaluated by monitoring the use of the active films for packaging cheese curds and butter, respectively. The cellulose nanocrystals increased the mechanical strength of the films and reduced the water permeability and water activity. The active film had an antimicrobial effect on coagulase-positive staphylococci in cheese curds and reduced the oxidation of butter during storage.

  9. Bi-functional biobased packing of the cassava starch, glycerol, licuri nanocellulose and red propolis.

    PubMed

    Costa, Samantha Serra; Druzian, Janice Izabel; Machado, Bruna Aparecida Souza; de Souza, Carolina Oliveira; Guimarães, Alaíse Gil

    2014-01-01

    The aim of this study was to characterize and determine the bi-functional efficacy of active packaging films produced with starch (4%) and glycerol (1.0%), reinforced with cellulose nanocrystals (0-1%) and activated with alcoholic extracts of red propolis (0.4 to 1.0%). The cellulose nanocrystals used in this study were extracted from licuri leaves. The films were characterized using moisture, water-activity analyses and water vapor-permeability tests and were tested regarding their total phenolic compounds and mechanical properties. The antimicrobial and antioxidant efficacy of the films were evaluated by monitoring the use of the active films for packaging cheese curds and butter, respectively. The cellulose nanocrystals increased the mechanical strength of the films and reduced the water permeability and water activity. The active film had an antimicrobial effect on coagulase-positive staphylococci in cheese curds and reduced the oxidation of butter during storage. PMID:25383783

  10. Bi-Functional Biobased Packing of the Cassava Starch, Glycerol, Licuri Nanocellulose and Red Propolis

    PubMed Central

    Costa, Samantha Serra; Druzian, Janice Izabel; Machado, Bruna Aparecida Souza; de Souza, Carolina Oliveira; Guimarães, Alaíse Gil

    2014-01-01

    The aim of this study was to characterize and determine the bi-functional efficacy of active packaging films produced with starch (4%) and glycerol (1.0%), reinforced with cellulose nanocrystals (0–1%) and activated with alcoholic extracts of red propolis (0.4 to 1.0%). The cellulose nanocrystals used in this study were extracted from licuri leaves. The films were characterized using moisture, water-activity analyses and water vapor-permeability tests and were tested regarding their total phenolic compounds and mechanical properties. The antimicrobial and antioxidant efficacy of the films were evaluated by monitoring the use of the active films for packaging cheese curds and butter, respectively. The cellulose nanocrystals increased the mechanical strength of the films and reduced the water permeability and water activity. The active film had an antimicrobial effect on coagulase-positive staphylococci in cheese curds and reduced the oxidation of butter during storage. PMID:25383783

  11. Thermoelasticity of red blood cell membrane.

    PubMed Central

    Waugh, R; Evans, E A

    1979-01-01

    The elastic properties of the human red blood cell membrane have been measured as functions of temperature. The area compressibility modulus and the elastic shear modulus, which together characterize the surface elastic behavior of the membrane, have been measured over the temperature range of 2-50 degrees C with micropipette aspiration of flaccid and osmotically swollen red cells. In addition, the fractional increase in membrane surface area from 2-50 degrees C has been measured to give a value for the thermal area expansivity. The value of the elastic shear modulus at 25 degrees C was measured to be 6.6 X 10(-3) dyne/cm. The change in the elastic shear modulus with temperature was -6 X 10(-5) dyne/cm degrees C. Fractional forces were shown to be only on the order of 10-15%. The area compressibility modulus at 25 degrees C was measured to be 450 dyne/cm. The change in the area compressibility modulus with temperature was -6 dyne/cm degrees C. The thermal area expansivity for red cell membrane was measured to be 1.2 X 10(-3)/degrees C. With this data and thermoelastic relations the heat of expansion is determined to be 110-200 ergs/cm2; the heat of extension is 2 X 10(-2) ergs/cm2 for unit extension of the red cell membrane. The heat of expansion is of the order anticipated for a lipid bilayer idealized as twice the behavior of a monolayer at an oil-water interface. The observation that the heat of extension is positive demonstrates that the entropy of the material increases with extension, and that the dominant mechanism of elastic energy storage is energetic. Assuming that the red cell membrane shear rigidity is associated with "spectrin," unit extension of the membrane increases the configurational entropy of spectrin by 500 cal/mol. Images FIGURE 3 PMID:262408

  12. The role of filament-packing dynamics in powering amoeboid cell motility

    PubMed Central

    Miao, Long; Vanderlinde, Orion; Liu, Jun; Grant, Richard P.; Wouterse, Alan; Shimabukuro, Katsuya; Philipse, Albert; Stewart, Murray; Roberts, Thomas M.

    2008-01-01

    Although several models have been proposed to account for how cytoskeleton polymerization drives protrusion in cell motility, the precise mechanism remains controversial. Here, we show that, in addition to force exerted directly against the membrane by growing filaments, the way elongating filaments pack also contributes to protrusion by generating an expansion of the cytoskeleton gel. Tomography shows that filament packing in the major sperm protein (MSP) -based nematode sperm-motility machinery resembles that observed with rigid rods. Maximum rod-packing density decreases dramatically as the rods lengthen. Therefore, as filaments elongate, the cytoskeleton gel expands to accommodate their packing less densely. This volume expansion combines with polymerization to drive protrusion. Consistent with this hypothesis, an engineered MSP mutant that generates shorter filaments shows higher filament-packing density and slower movement. PMID:18385381

  13. Properties of Hemoglobin Solutions in Red Cells

    PubMed Central

    Gary-Bobo, C. M.; Solomon, A. K.

    1968-01-01

    The present studies are concerned with a detailed examination of the apparent anomalous osmotic behavior of human red cells. Red cell water has been shown to behave simultaneously as solvent water for nonelectrolytes and nonsolvent water, in part, for electrolytes. The nonsolvent properties are based upon assumptions inherent in the conventional van't Hoff equation. However, calculations according to the van't Hoff equation give osmotic volumes considerably in excess of total cell water when the pH is lowered beyond the isoelectric point for hemoglobin; hence the van't Hoff equation is inapplicable for the measurement of the solvent properties of the red cell. Furthermore, in vitro measurements of osmotic and other properties of 3.7 millimolal solutions of hemoglobin have failed to reveal the presence of any salt exclusion. A new hypothesis has been developed from thermodynamic principles alone, which predicts that, at constant pH, the net charge on the hemoglobin molecule decreases with increased hemoglobin concentration. The existence of such cooperative interaction may be inferred from the effect of pH on the changes in hemoglobin net charge as the spacing between the molecules decreases. The resultant movement of counterions across the cell membrane causes the apparent anomalous osmotic behavior. Quantitative agreement has been found between the anion shift predicted by the equation and that observed in response to osmotic gradients. The proposed mechanism appears to be operative in a variety of tissues and could provide an electrical transducer for osmotic signals. PMID:5688085

  14. 21 CFR 864.8185 - Calibrator for red cell and white cell counting.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Calibrator for red cell and white cell counting... Calibrator for red cell and white cell counting. (a) Identification. A calibrator for red cell and white cell counting is a device that resembles red or white blood cells and that is used to set instruments...

  15. 21 CFR 864.8185 - Calibrator for red cell and white cell counting.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Calibrator for red cell and white cell counting... Calibrator for red cell and white cell counting. (a) Identification. A calibrator for red cell and white cell counting is a device that resembles red or white blood cells and that is used to set instruments...

  16. 21 CFR 864.8185 - Calibrator for red cell and white cell counting.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Calibrator for red cell and white cell counting... Calibrator for red cell and white cell counting. (a) Identification. A calibrator for red cell and white cell counting is a device that resembles red or white blood cells and that is used to set instruments...

  17. 21 CFR 864.8185 - Calibrator for red cell and white cell counting.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Calibrator for red cell and white cell counting... Calibrator for red cell and white cell counting. (a) Identification. A calibrator for red cell and white cell counting is a device that resembles red or white blood cells and that is used to set instruments...

  18. 21 CFR 864.8185 - Calibrator for red cell and white cell counting.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Calibrator for red cell and white cell counting... Calibrator for red cell and white cell counting. (a) Identification. A calibrator for red cell and white cell counting is a device that resembles red or white blood cells and that is used to set instruments...

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

    Code of Federal Regulations, 2014 CFR

    2014-04-01

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

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

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Red blood cell enzyme assay. 864.7100 Section 864...) 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. 21 CFR 660.30 - Reagent Red Blood Cells.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

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

  2. 21 CFR 864.7100 - Red blood cell enzyme assay.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

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

  3. 21 CFR 660.30 - Reagent Red Blood Cells.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

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

  4. 21 CFR 660.30 - Reagent Red Blood Cells.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

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

  5. 21 CFR 864.7100 - Red blood cell enzyme assay.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

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

  6. 21 CFR 660.30 - Reagent Red Blood Cells.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

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

  7. 21 CFR 660.30 - Reagent Red Blood Cells.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

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

  8. 21 CFR 864.7100 - Red blood cell enzyme assay.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

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

  9. Anemia and transfusion of red blood cells.

    PubMed

    Cortés Buelvas, Armando

    2013-10-01

    The red cells transfusion is a mainstay in the treatment of anemic patients. These blood transfusions are not without risks. The risk-benefit profile for red cell transfusions to treat anaemia is uncertain, but they may contribute to adverse patient outcomes in some situations. The ability of a patient to tolerate anaemia depends on their clinical condition and the presence of any significant co-morbidity; maintenance of circulating volume is of paramount importance. There is no universal transfusion trigger. Advances in the development and validation of physiological, accessible, practical and reliable markers to guide therapy are expected. To improve patients' outcomes, further study is required to more fully explore the risk of anemia, optimal hemoglobin level, and the risk and efficacy of RBC transfusion. Future clinical investigations with high priority should determine the efficacy of transfusion in those classified as uncertain scenarios. In the absence of data, it is prudent that transfusion is administered with caution in these clinical scenarios.

  10. Reversibility of red blood cell deformation

    NASA Astrophysics Data System (ADS)

    Zeitz, Maria; Sens, P.

    2012-05-01

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

  11. Multiscale simulation of red blood cell aggregation

    NASA Astrophysics Data System (ADS)

    Bagchi, P.; Popel, A. S.

    2004-11-01

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

  12. [Current aspects in red blood cell substitutes].

    PubMed

    Wang, Yanfeng; Pan, Jilun; Yu, Yaoting

    2004-06-01

    Red blood cell substitutes are a group of oxygen carriers designed to temporarily replace transfused blood. Current developing products include perfluorocarbon-based and hemoglobin-based oxygen carrier. Each product is unique in its limitations and advantages. A number of products are in advanced clinical trials and nearing market. When they are available for use it is likely that development will accelerate and even better products will substantially alleviate the world-wide shortage of blood for transfusion.

  13. From Red Cells to Soft Porous Lubrication

    NASA Astrophysics Data System (ADS)

    Wu, Qianhong; Gacka, Thomas; Nathan, Rungun; Crawford, Robert; Vucbmss Team

    2014-11-01

    Biological scientists have wondered, since the motion of red cells was first observed in capillaries, how the highly flexible red cell can move with so little friction in tightly fitting microvessels without being damaged or undergoing hemolysis. Theoretical studies (Feng and Weinbaum, 2000, JFM; Wu et al., 2004, PRL) attributed this frictionless motion to the dramatically enhanced hydrodynamic lifting force generated inside the soft, porous, endothelial surface layer (ESL) covering the inner surfaces of our capillaries, as a red blood cell glides over it. Herein we report the first experimental examination of this concept. The results conclusively demonstrate that significant fraction of the overall lifting force generated in a soft porous layer as a planing surface glides over it, is contributed by the pore fluid pressure, and thus frictional loss is reduced significantly. Moreover, the experimental predictions showed excellent agreement with the experimental data. This finding has the potential of dramatically changing existing lubrication approaches, and can result in substantial savings in energy consumption and thus reduction in greenhouse gas emissions.

  14. Red blood cell transfusion in newborn infants.

    PubMed

    Whyte, Robin K; Jefferies, Ann L

    2014-04-01

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

  15. Studies with nonradioisotopic sodium chromate. I. Development of a technique for measuring red cell volume

    SciTech Connect

    Heaton, W.A.; Hanbury, C.M.; Keegan, T.E.; Pleban, P.; Holme, S. )

    1989-10-01

    A nonradioisotopic method for measuring red cell volume that involves the use of 52Cr-sodium chromate as the red cell label and of graphite furnace atomic absorption analysis of chromium is described. The technique allows the labelling of 20 mL of packed red cells with 40 to 50 micrograms of sodium chromate (Na2CrO4) in 30 minutes at 22 degrees C with 94 +/- 6 percent uptake. Approximately 40 micrograms of Na2CrO4 was injected for in vivo studies. This results in posttransfusion in vivo red cell chromium levels after sample processing in the range of 1 to 7 micrograms per L, which could be quantitated accurately (coefficient of variation = 4.7%) by Zeeman electrothermal atomic absorption spectrophotometry. The labeling concentration of chromium did not cause increased hemolysis, and the labeled cells exhibited an osmotic fragility curve similar to that of unlabeled, fresh ACD red cells. Red cell glutathione peroxidase was unaffected by labeling, although glutathione reductase was reduced by approximately 13 percent (p less than 0.05). The 52Cr red cell volume-measuring method was evaluated by concurrent in vivo studies with the standard 51Cr and 125I-albumin methods for that procedure. Simultaneous measurement of red cell volumes in seven volunteers by the 51Cr, 52Cr, and 125I-albumin techniques correlated highly with each other (r greater than 0.76), with mean values of 2294 +/- 199, 2191 +/- 180, and 2243 +/- 291 mL, respectively. The standard deviations of the differences were small: 134 mL for 52Cr versus 51Cr and 183 mL for 52Cr versus 125I.

  16. Dependence of technetium-99m red blood cell labeling efficiency on red cell surface charge.

    PubMed

    Seldin, D W; Simchon, S; Jan, K M; Chien, S; Alderson, P O

    1988-10-01

    The mechanisms by which [99mTc]pertechnetate becomes attached to stannous-primed red blood cells are not known in detail. To study the problem further, the effect of red cell surface charge on labeling efficiency was evaluated. Red cell surface charge was reduced by using the enzyme neuraminidase to remove the terminal charge-bearing sialic acid moiety of the membrane glycoprotein. Forty-five blood samples from six volunteers were treated with neuraminidase for varying lengths of time, resulting in the removal of from 11% to 99% of the normal negative surface charge, as determined from electrophoretic mobility measurements. There was excellent linear correlation between labeling efficiency and the remaining red cell surface charge for values down to 20% of normal (r = 0.89). When surface charge was less than 20% of normal, labeling efficiency was constant at 30%. Eleven blood samples from three donors were divided into two groups that were treated with neuraminidase either before or after they were labeled. The labeling efficiency was independent of the order in which the steps were performed. No evidence for shifting of the radiolabel from the cell membrane to hemoglobin was found. The results suggest that clinical conditions associated with a reduction of sialic acid on the erythrocyte membrane may be one cause of decreased red blood cell labeling efficiency, and that increased membrane permeability for reduced technetium species may be responsible for the decrease.

  17. Osmotic properties of human red cells.

    PubMed

    Solomon, A K; Toon, M R; Dix, J A

    1986-01-01

    When an osmotic pressure gradient is applied to human red cells, the volume changes anomalously, as if there were a significant fraction of "nonosmotic water" which could not serve as solvent for the cell solutes, a finding which has been discussed widely in the literature. In 1968, Gary-Bobo and Solomon (J. Gen. Physiol. 52:825) concluded that the anomalies could not be entirely explained by the colligative properties of hemoglobin (Hb) and proposed that there was an additional concentration dependence of the Hb charge (ZHb). A number of investigators, particularly Freedman and Hoffman (1979, J. Gen. Physiol. 74:157) have been unable to confirm Gary-Bobo and Solomon's experimental evidence for this concentration dependence of ZHb and we now report that we are also unable to repeat the earlier experiments. Nonetheless, there still remains a significant anomaly which amounts to 12.5 +/- 0.8% of the total isosmotic cell water (P much less than 0.0005, t test), even after taking account of the concentration dependence of the Hb osmotic coefficient and all the other known physical chemical constraints, ideal and nonideal. It is suggested that the anomalies at high Hb concentration in shrunken cells may arise from the ionic strength dependence of the Hb osmotic coefficient. In swollen red cells at low ionic strength, solute binding to membrane and intracellular proteins is increased and it is suggested that this factor may account, in part, for the anomalous behavior of these cells.

  18. Effects of red cell transfusion on cardiac output and blood flow velocities in cerebral and gastrointestinal arteries in premature infants.

    PubMed Central

    Nelle, M; Höcker, C; Zilow, E P; Linderkamp, O

    1994-01-01

    Anaemia may increase the risk of tissue hypoxia in preterm infants. The effect of transfusion on circulation was studied in 33 preterm infants with a mean (SD) gestational age of 29 (5) weeks (range 26-34), birth weight 1153 (390) g (range 520-1840), and postnatal age of 48 (21) days (range 19-100). Packed cell volume, blood viscosity (capillary viscometer), cardiac output, and cerebral blood flow velocities in the internal carotid artery, anterior cerebral artery, and coeliac trunk (Doppler ultrasound) were determined before and after transfusion of 10 ml/kg of packed red blood cells. Transfusion increased packed cell volume from a mean (SD) 0.27 (0.45) to 0.37 (0.48). Mean arterial blood pressure did not change while heart rate decreased significantly from 161 (14) l/min to 149 (12). Cardiac output decreased from 367 (93) ml/kg/min to 311 (74) due to decrease in stroke volume from 2.28 (0.57) ml/kg to 2.14 (0.46) and in heart rate. There was a significant increase in systemic red cell transport (cardiac output times packed cell volume) by 17%, systemic flow resistance (blood pressure to cardiac output ratio) by 23%, and blood viscosity by 33%. Vascular hindrance (flow resistance to blood viscosity ratio) did not change significantly, thereby suggesting that neither vasoconstriction nor vasodilation occurred with transfusion. After transfusion blood flow velocities decreased significantly in the anterior cerebral artery by 23%, in the internal carotid artery by 8%, and in the coeliac trunk by 12%. Red cell transport estimated as products of blood flow velocities times packed cell volume increased significantly by 25% in the internal carotid artery and by 21% in the coeliac trunk. These results indicate that red cell transfusion improved systemic oxygen transport as well as oxygen transport in the internal carotid artery and coeliac trunk. PMID:8092871

  19. Osmotic water permeability of human red cells

    SciTech Connect

    Terwilliger, T.C.; Solomon, A.K.

    1981-05-01

    The osmotic water permeability of human red cells has been reexamined with a stopped-flow device and a new perturbation technique. Small osmotic gradients are used to minimize the systematic error caused by nonlinearities in the relationship between cell volume and light scattering. Corrections are then made for residual systematic error. Our results show that the hydraulic conductivity, Lp, is essentially independent of the direction of water flow and of osmolality in the range 184-365 mosM. the mean value of Lp obtained obtained was 1.8 +/- 0.1 (SEM) X 10-11 cm3 dyne -1 s-1.

  20. What makes red cells dysmorphic in glomerular haematuria?

    PubMed

    Rath, B; Turner, C; Hartley, B; Chantler, C

    1992-09-01

    Although red cell morphology has been used to localise the site of haematuria in the urinary tract, the cause of red cell deformity is still speculative. We have conducted experiments in vitro using venous red cells which indicate that hypochromia depends mainly upon sodium concentration and occurs when this falls below 75 mmol/l. We simulated the passage of red cells through the renal tubule by sequentially treating them with fluids of composition similar to those in different tubular segments, and produced anisocytosis and hypochromia but not the typical "bizarre deformity"--the hallmark of glomerular haematuria. We conclude that dual injury is required to produce the "typical" dysmorphic red cells in glomerular haematuria. First, mechanical damage caused by passage of red blood cells through the glomerular basement membrane followed by a second, osmotic, injury sustained by red cells during passage through the hypotonic tubular segment. PMID:1457323

  1. Neocytolysis: physiological down-regulator of red-cell mass

    NASA Technical Reports Server (NTRS)

    Alfrey, C. P.; Rice, L.; Udden, M. M.; Driscoll, T. B.

    1997-01-01

    It is usually considered that red-cell mass is controlled by erythropoietin-driven bone marrow red-cell production, and no physiological mechanisms can shorten survival of circulating red cells. In adapting to acute plethora in microgravity, astronauts' red-cell mass falls too rapidly to be explained by diminished red-cell production. Ferrokinetics show no early decline in erythropolesis, but red cells radiolabelled 12 days before launch survive normally. Selective destruction of the youngest circulating red cells-a process we call neocytolysis-is the only plausible explanation. A fall in erythropoietin below a threshold is likely to initiate neocytolysis, probably by influencing surface-adhesion molecules. Recognition of neocytolysis will require re-examination of the pathophysiology and treatment of several blood disorders, including the anaemia of renal disease.

  2. Simulations of molecular diffusion in lattices of cells: insights for NMR of red blood cells.

    PubMed Central

    Regan, David G; Kuchel, Philip W

    2002-01-01

    The pulsed field-gradient spin-echo (PGSE) nuclear magnetic resonance (NMR) experiment, conducted on a suspension of red blood cells (RBC) in a strong magnetic field yields a q-space plot consisting of a series of maxima and minima. This is mathematically analogous to a classical optical diffraction pattern. The method provides a noninvasive and novel means of characterizing cell suspensions that is sensitive to changes in cell shape and packing density. The positions of the features in a q-space plot characterize the rate of exchange across the membrane, cell dimensions, and packing density. A diffusion tensor, containing information regarding the diffusion anisotropy of the system, can also be derived from the PGSE NMR data. In this study, we carried out Monte Carlo simulations of diffusion in suspensions of "virtual" cells that had either biconcave disc (as in RBC) or oblate spheroid geometry. The simulations were performed in a PGSE NMR context thus enabling predictions of q-space and diffusion tensor data. The simulated data were compared with those from real PGSE NMR diffusion experiments on RBC suspensions that had a range of hematocrit values. Methods that facilitate the processing of q-space data were also developed. PMID:12080109

  3. Impact of glycocalyx structure on red cell-red cell affinity in polymer suspensions.

    PubMed

    Rad, Samar; Meiselman, Herbert J; Neu, Björn

    2014-11-01

    A theoretical framework based on macromolecular depletion has been utilized in order to examine the energetics of red blood cell interactions. Three different glycocalyx structures are considered and cell-cell affinities are calculated by superposition of depletion, steric and electrostatic interactions. The theoretical model predicts a non-monotonic dependence of the interaction energies on polymer size. Further, our results indicate that the glycocalyx segment distribution has a large impact on adhesion energies between cells: a linear segment distribution induces the strongest adhesion between cells followed by pseudo-tail and uniform distributions. Our approach confirms the concept of a depletion mechanism for RBC aggregation, and also provides new insights that may eventually help to understand and quantify cellular factors that control red blood cell interactions in health and disease.

  4. Anesthetics and red blood cell rheology

    NASA Astrophysics Data System (ADS)

    Aydogan, Burcu; Aydogan, Sami

    2014-05-01

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

  5. Hemoglobin-based red blood cell substitutes.

    PubMed

    Chang, Thomas Ming Swi

    2004-09-01

    Polyhemoglobin is already well into the final stages of clinical trials in humans with one approved for routine clinical use in South Africa. Conjugated hemoglobin is also in ongoing clinical trials. Meanwhile, recombinant Hb has been modified to modulate the effects of nitric oxide. Other systems contain antioxidant enzymes for those clinical applications that may have potential problems related to ischemia-reperfusion injuries. Other developments are based on hemoglobin-lipid vesicles and also the use of nanotechnology and biodegradable copolymers to prepare nanodimension artificial red blood cells containing hemoglobin and complex enzyme systems.

  6. Oxygen supply for CHO cells immobilized on a packed-bed of Fibra-Cel disks.

    PubMed

    Meuwly, F; Loviat, F; Ruffieux, P-A; Bernard, A R; Kadouri, A; von Stockar, U

    2006-03-01

    Packed-bed bioreactors (PBR) have proven to be efficient systems to culture mammalian cells at very high cell density in perfusion mode, thus leading to very high volumetric productivity. However, the immobilized cells must be continuously supplied with all nutrients in sufficient quantities to remain viable and productive over the full duration of the perfusion culture. Among all nutrients, oxygen is the most critical since it is present at very low concentration due to its low solubility in cell culture medium. This work presents the development of a model for oxygenation in a packed-bed bioreactor system. The experimental system used to develop the model was a packed-bed of Fibra-Cel disk carriers used to cultivate Chinese Hamster Ovary cells at high density ( approximately 6.1 x 10(7) cell/mL) in perfusion mode. With the help of this model, it was possible to identify if a PBR system is operated in optimal or sub-optimal conditions. Using the model, two options were proposed, which could improve the performance of the basal system by about twofold, that is, by increasing the density of immobilized cells per carrier volume from 6.1 x 10(7) to 1.2 x 10(8) cell/mL, or by increasing the packed-bed height from 0.2 to 0.4 m. Both strategies would be rather simple to test and implement in the packed-bed bioreactor system used for this study. As a result, it would be possible to achieve a substantial improvement of about twofold higher productivity as compared with the basal conditions.

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

    SciTech Connect

    Knoll, S.E.

    1991-08-01

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

  8. Red blood cell volume in preterm neonates

    SciTech Connect

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

    1981-10-01

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

  9. Red cell antigens: Structure and function

    PubMed Central

    Pourazar, Abbasali

    2007-01-01

    Landsteiner and his colleagues demonstrated that human beings could be classified into four groups depending on the presence of one (A) or another (B) or both (AB) or none (O) of the antigens on their red cells. The number of the blood group antigens up to 1984 was 410. In the next 20 years, there were 16 systems with 144 antigens and quite a collection of antigens waiting to be assigned to systems, pending the discovery of new information about their relationship to the established systems. The importance of most blood group antigens had been recognized by immunological complications of blood transfusion or pregnancies; their molecular structure and function however remained undefined for many decades. Recent advances in molecular genetics and cellular biochemistry resulted in an abundance of new information in this field of research. In this review, we try to give some examples of advances made in the field of ‘structure and function of the red cell surface molecules.’ PMID:21938229

  10. Mechanosensing Dynamics of Red blood Cells

    NASA Astrophysics Data System (ADS)

    Wan, Jiandi

    2015-11-01

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

  11. Blood parasites, total plasma protein and packed cell volume of small wild mammals trapped in three mountain ranges of the Atlantic Forest in Southeastern Brazil.

    PubMed

    Silva, M A M L; Ronconi, A; Cordeiro, N; Bossi, D E P; Bergallo, H G; Costa, M C C; Balieiro, J C C; Varzim, F L S B

    2007-08-01

    A study of blood parasites in small wild non-flying mammals was undertaken in three areas of the Atlantic Forest in Southeastern Brazil: Serra de Itatiaia, RJ, Serra da Bocaina, SP and Serra da Fartura, SP, from June 1999 to May 2001. A total of 450 animals (15 species) were captured in traps and it was observed in 15.5% of the blood smears the presence of Haemobartonella sp. and Babesia sp. in red blood cells. There was no statistically significant difference between parasited and non-parasited specimens regarding total plasma protein, packed cell volume and body weight, which strongly suggests that these specimens might be parasite reservoirs.

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

    PubMed

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

    2015-12-01

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

  13. A power pack based on organometallic perovskite solar cell and supercapacitor.

    PubMed

    Xu, Xiaobao; Li, Shaohui; Zhang, Hua; Shen, Yan; Zakeeruddin, Shaik M; Graetzel, Michael; Cheng, Yi-Bing; Wang, Mingkui

    2015-02-24

    We present an investigation on a power pack combining a CH3NH3PbI3-based solar cell with a polypyrrole-based supercapacitor and evaluate its performance as an energy pack. The package achieved an energy storage efficiency of 10%, which is much higher than that of other systems combining a PV cell with a supercapacitor. We find a high output voltage of 1.45 V for the device under AM 1.5G illumination when the CH3NH3PbI3-based solar cell is connected in series with a polypyrrole-based supercapacitor. This system affords continuous output of electric power by using CH3NH3PbI3-based solar cell as an energy source mitigating transients caused by light intensity fluctuations or the diurnal cycle.

  14. Single scattering by red blood cells.

    PubMed

    Hammer, M; Schweitzer, D; Michel, B; Thamm, E; Kolb, A

    1998-11-01

    A highly diluted suspension of red blood cells (hematocrit 0.01) was illuminated with an Ar or a dye laser in the wavelength range of 458-660 nm. The extinction and the angle-resolved intensity of scattered light were measured and compared with the predictions of Mie theory, the Rayleigh-Gans approximation, and the anomalous diffraction approximation. Furthermore, empirical phase functions were fitted to the measurements. The measurements were in satisfactory agreement with the predictions of Mie theory. However, better agreement was found with the anomalous diffraction model. In the Rayleigh-Gans approximation, only small-angle scattering is described appropriately. The scattering phase function of erythrocytes may be represented by the Gegenbauer kernel phase function. PMID:18301575

  15. Hemoglobin s polymerization and red cell membrane changes.

    PubMed

    Kuypers, Frans A

    2014-04-01

    Different pathways lead from the simple point mutation in hemoglobin to the membrane changes that characterize the altered interaction of the sickle red blood cell with its environment, including endothelial cells, white blood cells, and platelets. Polymerization and oxidation-induced damage to both lipid and protein components of the red cell membrane, as well as the generation of bioreactive membrane material (microparticles), has a profound effect on all tissues and organs, and defines the vasculopathy of the patient with sickle cell disease.

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

    NASA Technical Reports Server (NTRS)

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

    1996-01-01

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

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

    SciTech Connect

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

    1983-01-01

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

  18. Control of red blood cell mass during spaceflight

    NASA Technical Reports Server (NTRS)

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

    1996-01-01

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

  19. Hemobilia detected by Tc-99m labeled red blood cells

    SciTech Connect

    Winzelberg, G.G.; Wholey, M.H.; Ismail-Beigi, F.

    1982-01-01

    Tc-99m labeled red blood cells were successfully used to determine the site of hemorrhage in a 67-year-old man with hemobilia. A false hepatic artery aneurysm was confirmed at angiography and ultimately successfully embolized. The relative merits of using Tc-99m labeled red blood cells for detecting sources of upper gastrointestinal bleeding are discussed.

  20. Rh antibodies against the pretransplant red cells following Rh-incompatible bone marrow transplantation.

    PubMed

    Heim, M U; Schleuning, M; Eckstein, R; Huhn, D; Siegert, W; Clemm, C; Ledderose, G; Kolb, H J; Wilmanns, W; Mempel, W

    1988-01-01

    A 22-year-old, blood group O, Rh-positive (R2r) man received bone marrow from his blood group A, Rh-negative (rr), HLA-identical sister for treatment of acute lymphocytic leukemia. The patient's pretransplantation serum contained anti-A in a low concentration; therefore, plasmapheresis was not done prior to transfusion of bone marrow. To prevent graft-versus-host disease, bone marrow was incubated with absorbed rabbit antithymocyte globulin prior to infusion, and the patient was treated with methotrexate in the posttransplantation period. After transplantation, the patient received 6 units of group O, Rh-negative (rr) packed red cells from random donors and 6 units of platelets from the marrow donor. Three months after transplantation, 0.5 percent of his red cells were still of the host's type (group O, Rh-positive), as detected by immunofluorescence technique in blood smears. Four months after transplantation, three different Rh antibodies--anti-D, -E, and -G--were detected. Since the patient received only Rh-negative red cell transfusions, it is concluded that he was immunized to his original red cells.

  1. Rh antibodies against the pretransplant red cells following Rh-incompatible bone marrow transplantation.

    PubMed

    Heim, M U; Schleuning, M; Eckstein, R; Huhn, D; Siegert, W; Clemm, C; Ledderose, G; Kolb, H J; Wilmanns, W; Mempel, W

    1988-01-01

    A 22-year-old, blood group O, Rh-positive (R2r) man received bone marrow from his blood group A, Rh-negative (rr), HLA-identical sister for treatment of acute lymphocytic leukemia. The patient's pretransplantation serum contained anti-A in a low concentration; therefore, plasmapheresis was not done prior to transfusion of bone marrow. To prevent graft-versus-host disease, bone marrow was incubated with absorbed rabbit antithymocyte globulin prior to infusion, and the patient was treated with methotrexate in the posttransplantation period. After transplantation, the patient received 6 units of group O, Rh-negative (rr) packed red cells from random donors and 6 units of platelets from the marrow donor. Three months after transplantation, 0.5 percent of his red cells were still of the host's type (group O, Rh-positive), as detected by immunofluorescence technique in blood smears. Four months after transplantation, three different Rh antibodies--anti-D, -E, and -G--were detected. Since the patient received only Rh-negative red cell transfusions, it is concluded that he was immunized to his original red cells. PMID:3130695

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

    PubMed Central

    Mairbäurl, Heimo

    2013-01-01

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

  3. Red blood cells in retinal vascular disorders.

    PubMed

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

    2016-01-01

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

  4. Developmental Plasticity of Red Blood Cell Homeostasis

    PubMed Central

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

    2014-01-01

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

  5. Red blood cell in simple shear flow

    NASA Astrophysics Data System (ADS)

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

    2013-03-01

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

  6. Red blood cell storage duration and trauma.

    PubMed

    Sparrow, Rosemary L

    2015-04-01

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

  7. Impact of cellular properties on red cell-red cell affinity in plasma-like suspensions

    NASA Astrophysics Data System (ADS)

    Rad, S.; Neu, B.

    2009-10-01

    The reversible aggregation of human red blood cells (RBC) by proteins or polymers continues to be of biological and biophysical interest, yet the mechanistic details governing this process are still being explored. In this report an approach is described to compute the interaction energy between RBC by considering cellular properties as well as polymer properties. Cell-cell affinities were calculated as functions of glycocalyx thickness and glycocalyx volume concentration as well as bulk polymer concentration. Our theoretical predictions show that cell-cell affinities do not monotonically increase with polymer size and concentration, but rather demonstrate an optimum dextran molecular mass and concentration which depends on cellular properties of RBC. These results show qualitative agreement with recent experimental observations. In conclusion, our model not only confirms the concept of a depletion mechanism for RBC aggregation but also provides new insights which should help understanding how cellular properties control in vivo RBC interactions.

  8. Packed Bed Bioreactor for the Isolation and Expansion of Placental-Derived Mesenchymal Stromal Cells

    PubMed Central

    Osiecki, Michael J.; Michl, Thomas D.; Kul Babur, Betul; Kabiri, Mahboubeh; Atkinson, Kerry; Lott, William B.; Griesser, Hans J.; Doran, Michael R.

    2015-01-01

    Large numbers of Mesenchymal stem/stromal cells (MSCs) are required for clinical relevant doses to treat a number of diseases. To economically manufacture these MSCs, an automated bioreactor system will be required. Herein we describe the development of a scalable closed-system, packed bed bioreactor suitable for large-scale MSCs expansion. The packed bed was formed from fused polystyrene pellets that were air plasma treated to endow them with a surface chemistry similar to traditional tissue culture plastic. The packed bed was encased within a gas permeable shell to decouple the medium nutrient supply and gas exchange. This enabled a significant reduction in medium flow rates, thus reducing shear and even facilitating single pass medium exchange. The system was optimised in a small-scale bioreactor format (160 cm2) with murine-derived green fluorescent protein-expressing MSCs, and then scaled-up to a 2800 cm2 format. We demonstrated that placental derived MSCs could be isolated directly within the bioreactor and subsequently expanded. Our results demonstrate that the closed system large-scale packed bed bioreactor is an effective and scalable tool for large-scale isolation and expansion of MSCs. PMID:26660475

  9. Packed Bed Bioreactor for the Isolation and Expansion of Placental-Derived Mesenchymal Stromal Cells.

    PubMed

    Osiecki, Michael J; Michl, Thomas D; Kul Babur, Betul; Kabiri, Mahboubeh; Atkinson, Kerry; Lott, William B; Griesser, Hans J; Doran, Michael R

    2015-01-01

    Large numbers of Mesenchymal stem/stromal cells (MSCs) are required for clinical relevant doses to treat a number of diseases. To economically manufacture these MSCs, an automated bioreactor system will be required. Herein we describe the development of a scalable closed-system, packed bed bioreactor suitable for large-scale MSCs expansion. The packed bed was formed from fused polystyrene pellets that were air plasma treated to endow them with a surface chemistry similar to traditional tissue culture plastic. The packed bed was encased within a gas permeable shell to decouple the medium nutrient supply and gas exchange. This enabled a significant reduction in medium flow rates, thus reducing shear and even facilitating single pass medium exchange. The system was optimised in a small-scale bioreactor format (160 cm2) with murine-derived green fluorescent protein-expressing MSCs, and then scaled-up to a 2800 cm2 format. We demonstrated that placental derived MSCs could be isolated directly within the bioreactor and subsequently expanded. Our results demonstrate that the closed system large-scale packed bed bioreactor is an effective and scalable tool for large-scale isolation and expansion of MSCs.

  10. Packed Bed Bioreactor for the Isolation and Expansion of Placental-Derived Mesenchymal Stromal Cells.

    PubMed

    Osiecki, Michael J; Michl, Thomas D; Kul Babur, Betul; Kabiri, Mahboubeh; Atkinson, Kerry; Lott, William B; Griesser, Hans J; Doran, Michael R

    2015-01-01

    Large numbers of Mesenchymal stem/stromal cells (MSCs) are required for clinical relevant doses to treat a number of diseases. To economically manufacture these MSCs, an automated bioreactor system will be required. Herein we describe the development of a scalable closed-system, packed bed bioreactor suitable for large-scale MSCs expansion. The packed bed was formed from fused polystyrene pellets that were air plasma treated to endow them with a surface chemistry similar to traditional tissue culture plastic. The packed bed was encased within a gas permeable shell to decouple the medium nutrient supply and gas exchange. This enabled a significant reduction in medium flow rates, thus reducing shear and even facilitating single pass medium exchange. The system was optimised in a small-scale bioreactor format (160 cm2) with murine-derived green fluorescent protein-expressing MSCs, and then scaled-up to a 2800 cm2 format. We demonstrated that placental derived MSCs could be isolated directly within the bioreactor and subsequently expanded. Our results demonstrate that the closed system large-scale packed bed bioreactor is an effective and scalable tool for large-scale isolation and expansion of MSCs. PMID:26660475

  11. Heterogeneity, Cell Biology and Tissue Mechanics of Pseudostratified Epithelia: Coordination of Cell Divisions and Growth in Tightly Packed Tissues.

    PubMed

    Strzyz, P J; Matejcic, M; Norden, C

    2016-01-01

    Pseudostratified epithelia (PSE) are tightly packed proliferative tissues that are important precursors of the development of diverse organs in a plethora of species, invertebrate and vertebrate. PSE consist of elongated epithelial cells that are attached to the apical and basal side of the tissue. The nuclei of these cells undergo interkinetic nuclear migration (IKNM) which leads to all mitotic events taking place at the apical surface of the epithelium. In this review, we discuss the intricacies of proliferation in PSE, considering cell biological, as well as the physical aspects. First, we summarize the principles governing the invariability of apical nuclear migration and apical cell division as well as the importance of apical mitoses for tissue proliferation. Then, we focus on the mechanical and structural features of these tissues. Here, we discuss how the overall architecture of pseudostratified tissues changes with increased cell packing. Lastly, we consider possible mechanical cues resulting from these changes and their potential influence on cell proliferation.

  12. Abnormal Red Cell Structure and Function in Neuroacanthocytosis

    PubMed Central

    Cluitmans, Judith C. A.; Tomelleri, Carlo; Yapici, Zuhal; Dinkla, Sip; Bovee-Geurts, Petra; Chokkalingam, Venkatachalam; De Franceschi, Lucia; Brock, Roland; Bosman, Giel J. G. C. M.

    2015-01-01

    Background Panthothenate kinase-associated neurodegeneration (PKAN) belongs to a group of hereditary neurodegenerative disorders known as neuroacanthocytosis (NA). This genetically heterogeneous group of diseases is characterized by degeneration of neurons in the basal ganglia and by the presence of deformed red blood cells with thorny protrusions, acanthocytes, in the circulation. Objective The goal of our study is to elucidate the molecular mechanisms underlying this aberrant red cell morphology and the corresponding functional consequences. This could shed light on the etiology of the neurodegeneration. Methods We performed a qualitative and semi-quantitative morphological, immunofluorescent, biochemical and functional analysis of the red cells of several patients with PKAN and, for the first time, of the red cells of their family members. Results We show that the blood of patients with PKAN contains not only variable numbers of acanthocytes, but also a wide range of other misshapen red cells. Immunofluorescent and immunoblot analyses suggest an altered membrane organization, rather than quantitative changes in protein expression. Strikingly, these changes are not limited to the red blood cells of PKAN patients, but are also present in the red cells of heterozygous carriers without neurological problems. Furthermore, changes are not only present in acanthocytes, but also in other red cells, including discocytes. The patients’ cells, however, are more fragile, as observed in a spleen-mimicking device. Conclusion These morphological, molecular and functional characteristics of red cells in patients with PKAN and their family members offer new tools for diagnosis and present a window into the pathophysiology of neuroacanthocytosis. PMID:25933379

  13. Simulating T cell motility in the lymph node paracortex with a packed lattice geometry

    PubMed Central

    Bogle, Gib; Dunbar, P. Rod

    2009-01-01

    Agent-based simulation modeling of T cell trafficking, activation and proliferation in the lymph node paracortex requires a model for cell motility. Such a model must be able to reproduce the observed random-walk behaviour of T cells, while accommodating large numbers of tightly packed cells, and must be computationally efficient. We report the development of a motility model, based on a 3-D lattice geometry, that meets these objectives. Cells make discrete jumps between neighbouring lattice sites in directions that are randomly determined from specified discrete probability distributions, which are defined by a small number of parameters. It is shown that the main characteristics of the random motion of T cells as typically observed in vivo can be reproduced by suitable specification of model parameters. The model is computationally highly efficient, and provides a suitable engine for a model capable of simulating the full T cell population of the paracortex. PMID:18711399

  14. Absence of carbonic anhydrase on the surface of red cells suspended in an elutriator

    SciTech Connect

    Dodek, P.; Effros, R.M.

    1986-03-01

    Studies of the carbonic anhydrase activity of intact red cells are complicated by hemolysis, which markedly accelerates catalytic conversion between HCO/sub 2//sup -/ and CO/sub 2/. The authors have reduced this effect to negligible levels by studying red cells suspended with an elutriator. 1.Oml of packed rabbit red cells were introduced in an elutriator chamber which was spun in a centrifuge with a force of 2900G. An isotonic, pH 7.4, 6/sup 0/C, HCO/sub 3//sup -/ Ringer's lactate solution was pumped centripetally through the chamber to keep the cells in suspension. 0.1 ml of the perfusion solution containing /sup 22/Na/sup +/, /sup 36/Cl-, H/sup 14/CO/sub 3//sup -///sup 14/CO/sub 2/ (equilibrated), and /sup 3/H/sub 2/O were injected into the elutriator inflow and 22 samples were collected with a computerized anaerobic collector. Outflow concentrations of each radionuclide were divided by the amounts injected to yield fractional concentrations and upslope areas of indicators were divided by that of /sup 22/Na/sup +/ to yield an index of red cell exchange, R. Under control conditions, R(/sup 14/C) averaged .80 +/- .01 (S.E.). After anion exchange had been blocked with 0.1..mu..M DIDS, R(/sup 14/C) increased to .86 +/- .01. When 100 mg/1 bovine carbonic anhydrase was added R(/sup 1/$C) fell to .78 +/- .01. Subsequent addition of acetazolamide (10/sup -5/) increased R(/sup 14/C) to .86 +/- .01. R(/sup 36/Cl/sup -/) was increased from .91 +/- .02 to .96 +/- .01 after DIDS. These data indicate no detectable carbonic anhydrase activity on red cell surface.

  15. Lack of Erythropoietic Inhibitory Effect of Serum From Patients with Congenital Pure Red Cell Aplasia

    ERIC Educational Resources Information Center

    Geller, Gary; And Others

    1975-01-01

    Serum of five children ages 1 to 19 months with congenital pure red cell aplasia (incomplete or defective development of red blood cells) was injected in normal mice to determine possible inhibition of red blood cell formulating stimulants. (CL)

  16. A liquid film model of tetrakaidecahedral packing to account for the establishment of epidermal cell columns.

    PubMed

    Menton, D N

    1976-05-01

    The possiblity that the organization of cells into columns in the mammalian epidermis may be a result of the close packing of these cells has been investigated in a model system involving the association of randomly produced soap bubbles into a stable froth. Upon floating to the surface of a liquid, soap bubbles have been found to spontaneously assemble into precise columns of interdigitating bubbles. The tetrakaidecahedral shape and the spatial configuration of these bubbles closely resemble those of stacked epidermal cells, although the columns of a froth were oriented at a 60degrees angle to their substratum rather than at right angles as occurs in the epidermal cell columns. These observations lend support to the theory that the organization of the cells in the epidermis into columns is due to the assumption of the keratocytes of a minimum surface-close packing array. Such an organizing mechanism would be independent of both positional control of the underlying mitoses and active guidance of the cells as they become superficially displaced within the epidermis. The observation that a high rate of cell turnover is incompatible with the epidermal column structure may be related to the finding that rapidly produced soap bubbles do not, at least initially, assemble into a columnar array. PMID:1270835

  17. Human red blood cells' physiological water exchange with the plasma.

    PubMed

    Kargol, M; Kargol, A; Przestalski, M; Siedlecki, J; Karpińska, M; Rogowski, M

    2005-01-01

    In the present paper, fundamental issues related to the mechanisms of human red blood cells' physiological water exchange with the plasma (for the stationary conditions) have been discussed. It has been demonstrated, on the basis of mechanistic transport equations for membrane transport that red blood cells are capable of exchanging considerable amounts of water with the plasma. Water absorption is osmosis-driven, and its removal occurs according to the hydromechanics principle, i.e. is driven by the turgor pressure of red blood cells. This newly-acquired knowledge of these issues may appear highly useful for clinical diagnosis of blood diseases and blood circulation failures. PMID:16358974

  18. Integration Issues of Cells into Battery Packs for Plug-in and Hybrid Electric Vehicles: Preprint

    SciTech Connect

    Pesaran, A. A.; Kim, G. H.; Keyser, M.

    2009-05-01

    The main barriers to increased market share of hybrid electric vehicles (HEVs) and commercialization of plug-in HEVs are the cost, safety, and life of lithium ion batteries. Significant effort is being directed to address these issues for lithium ion cells. However, even the best cells may not perform as well when integrated into packs for vehicles because of the environment in which vehicles operate. This paper discusses mechanical, electrical, and thermal integration issues and vehicle interface issues that could impact the cost, life, and safety of the system. It also compares the advantages and disadvantages of using many small cells versus a few large cells and using prismatic cells versus cylindrical cells.

  19. Hyperbaric oxygen treatment of dogs has no effect on red cell deformability but causes an acute fluid shift.

    PubMed

    Martindale, V E; McKay, K

    1995-01-01

    Red blood cells respond to a number of perturbations, including hypoxia, with a reduction in deformability. Local hypoxia may become self-reinforcing, as hypoxic cells block capillaries preventing perfusion by oxygenated cells. Hyperbaric oxygen (HBO) is frequently used to treat conditions involving some degree of local hypoxia, but does it have a direct effect on deformability? To investigate this, 12 normal dogs received a 10 week "clinical" course of HBO: one 90 min treatment per weekday at 2.4 ATA (243 kPa), 100% O2. On Mondays and Fridays, a blood sample was drawn into EDTA, centrifuged, and the packed red blood cells resuspended in medium to a dilution of 2 x 10(6) to 5 x 10(6) cells/ml, and filtered under constant of 1.08 kPa through a precalibrated Nucleopore Hemafil Polycarbonate membrane. Filtrate was collected for one minute and weighed, and the red blood cell "incremental volume" calculated according to Engstrom (Engstrom and Ohlsson, Pediatric Res. 27:220-226, 1990). No significant change was seen in filtration rates, indicating that HBO itself neither improves nor impairs dog red blood cell deformability. Changes in other commonly measured blood parameters remained within clinical norms. An acute fluid shift out of red blood cells and into plasma was indicated.

  20. Effects of increased red cell mass on subclinical tissue acidosis in hyaline membrane disease.

    PubMed Central

    La Gamma, E F; Krauss, A; Auld, P A

    1996-01-01

    AIM: To determine whether there are subclinical deficits in oxygen delivery in ventilated premature neonates. METHOD: Ventilated premature neonates weighing less than 1500 g, who were transfused for anaemia or who were given colloids for clotting abnormalities (or oedema), were haemodynamically monitored during the first week of life. Calf muscle surface pH (pH) was measured in conjunction with peripheral limb blood flow by occlusion plethysmography. RESULTS: Packed red blood cell transfusions corrected a subclinical regional tissue acidosis (low tpH) without affecting arterial pH or limb blood flow. This observation also correlated with an increase in regional oxygen delivery. The data were also suggestive of a pattern of pathological, supply dependent, oxygen delivery and are similar to other observations made in adults with adult respiratory distress syndrome. CONCLUSIONS: Packed red blood cells increase regional oxygen delivery and tissue surface pH. In contrast, colloid infusion provided no substantial cardiovascular or metabolic benefit to these patients and should be avoided when oxygen delivery is at issue and when there may be leaky pulmonary capillaries. PMID:8949689

  1. Context aware spatio-temporal cell tracking in densely packed multilayer tissues.

    PubMed

    Chakraborty, Anirban; Roy-Chowdhury, Amit K

    2015-01-01

    Modern live imaging technique enables us to observe the internal part of a tissue over time by generating serial optical images containing spatio-temporal slices of hundreds of tightly packed cells. Automated tracking of plant and animal cells from such time lapse live-imaging datasets of a developing multicellular tissue is required for quantitative, high throughput analysis of cell division, migration and cell growth. In this paper, we present a novel cell tracking method that exploits the tight spatial topology of neighboring cells in a multicellular field as contextual information and combines it with physical features of individual cells for generating reliable cell lineages. The 2D image slices of multicellular tissues are modeled as a conditional random field and pairwise cell to cell similarities are obtained by estimating marginal probability distributions through loopy belief propagation on this CRF. These similarity scores are further used in a spatio-temporal graph labeling problem to obtain the optimal and feasible set of correspondences between individual cell slices across the 4D image dataset. We present results on (3D+t) confocal image stacks of Arabidopsis shoot meristem and show that the method is capable of handling many visual analysis challenges associated with such cell tracking problems, viz. poor feature quality of individual cells, low SNR in parts of images, variable number of cells across slices and cell division detection. PMID:25461334

  2. Dysferlin and other non-red cell proteins accumulate in the red cell membrane of Diamond-Blackfan Anemia patients.

    PubMed

    Pesciotta, Esther N; Sriswasdi, Sira; Tang, Hsin-Yao; Speicher, David W; Mason, Philip J; Bessler, Monica

    2014-01-01

    Diamond Blackfan Anemia (DBA) is a congenital anemia usually caused by diverse mutations in ribosomal proteins. Although the genetics of DBA are well characterized, the mechanisms that lead to macrocytic anemia remain unclear. We systematically analyzed the proteomes of red blood cell membranes from multiple DBA patients to determine whether abnormalities in protein translation or erythropoiesis contribute to the observed macrocytosis or alterations in the mature red blood cell membrane. In depth proteome analysis of red cell membranes enabled highly reproducible identification and quantitative comparisons of 1100 or more proteins. These comparisons revealed clear differences between red cell membrane proteomes in DBA patients and healthy controls that were consistent across DBA patients with different ribosomal gene mutations. Proteins exhibiting changes in abundance included those known to be increased in DBA such as fetal hemoglobin and a number of proteins not normally found in mature red cell membranes, including proteins involved in the major histocompatibility complex class I pathway. Most striking was the presence of dysferlin in the red blood cell membranes of DBA patients but absent in healthy controls. Immunoblot validation using red cell membranes isolated from additional DBA patients and healthy controls confirmed a distinct membrane protein signature specific to patients with DBA.

  3. Dysferlin and Other Non-Red Cell Proteins Accumulate in the Red Cell Membrane of Diamond-Blackfan Anemia Patients

    PubMed Central

    Pesciotta, Esther N.; Sriswasdi, Sira; Tang, Hsin-Yao; Speicher, David W.; Mason, Philip J.; Bessler, Monica

    2014-01-01

    Diamond Blackfan Anemia (DBA) is a congenital anemia usually caused by diverse mutations in ribosomal proteins. Although the genetics of DBA are well characterized, the mechanisms that lead to macrocytic anemia remain unclear. We systematically analyzed the proteomes of red blood cell membranes from multiple DBA patients to determine whether abnormalities in protein translation or erythropoiesis contribute to the observed macrocytosis or alterations in the mature red blood cell membrane. In depth proteome analysis of red cell membranes enabled highly reproducible identification and quantitative comparisons of 1100 or more proteins. These comparisons revealed clear differences between red cell membrane proteomes in DBA patients and healthy controls that were consistent across DBA patients with different ribosomal gene mutations. Proteins exhibiting changes in abundance included those known to be increased in DBA such as fetal hemoglobin and a number of proteins not normally found in mature red cell membranes, including proteins involved in the major histocompatibility complex class I pathway. Most striking was the presence of dysferlin in the red blood cell membranes of DBA patients but absent in healthy controls. Immunoblot validation using red cell membranes isolated from additional DBA patients and healthy controls confirmed a distinct membrane protein signature specific to patients with DBA. PMID:24454878

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

    PubMed Central

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

    2015-01-01

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

  5. Qualitative assessment of red blood cell parameters for signs of anemia in patients with chronic periodontitis

    PubMed Central

    Khan, Nubesh S.; Luke, Roji; Soman, Rino Roopak; Krishna, Praveen M.; Safar, Iqbal P.; Swaminathan, Senthil Kumar

    2015-01-01

    Aim: Anemia of chronic disease is defined as anemia occurring in chronic infections and inflammatory conditions that is not caused by marrow deficiencies or other diseases and in the presence of adequate iron stores and vitamins. The present case control study was aimed to assess the red blood cell parameters for signs of anemia in patients with mild, moderate, and severe chronic periodontitis. Materials and Methods: A simple random sampling method was used to select 80 healthy male patients, who were divided into four groups based on full mouth periodontal examination as follows: group I patients comprised the control group (n = 20), which included patients with a clinically healthy periodontium, group II patients (n = 20) were diagnosed with mild chronic periodontitis, group III (n = 20) included moderate chronic periodontitis patients, and patients with severe chronic periodontitis formed group IV (n = 20). Laboratory blood investigations included total number of erythrocytes, hemoglobin concentration, packed cell volume, mean corpuscular volume, mean corpuscular hemoglobin, and mean corpuscular hemoglobin concentration. Results: Data analysis showed a statistically significant decrease in red blood cell parameters with increase in different grades of periodontitis. Conclusion: Results of the present study show a substantial decrease in red blood cell parameters with increase in the severity of periodontal destruction. PMID:26759801

  6. Models for the red blood cell lifespan.

    PubMed

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

    2016-06-01

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

  7. Formation of dimethylthioarsenicals in red blood cells

    SciTech Connect

    Naranmandura, Hua; Suzuki, Kazuo T.

    2008-03-15

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

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

    PubMed

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

    2015-12-01

    Red blood cell counts have been proven to be one of the most frequently performed blood tests and are valuable for early diagnosis of some diseases. This paper describes an automated red blood cell counting method based on microscopic hyperspectral imaging technology. Unlike the light microscopy-based red blood count methods, a combined spatial and spectral algorithm is proposed to identify red blood cells by integrating active contour models and automated two-dimensional k-means with spectral angle mapper algorithm. Experimental results show that the proposed algorithm has better performance than spatial based algorithm because the new algorithm can jointly use the spatial and spectral information of blood cells. PMID:26554882

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

    SciTech Connect

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

    1984-07-01

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

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

    PubMed Central

    Zeidan, Adel; Yelin, Dvir

    2015-01-01

    Measuring the morphology of red blood cells is important for clinical diagnosis, providing valuable indications on a patient’s health. In this work, we have simulated the appearance of normal red blood cells under a reflectance confocal microscope and discovered unique relations between the morphological parameters and the resulting characteristic interference patterns of the cell. The simulation results showed good agreement with in vitro reflectance confocal images of red blood cells, acquired using spectrally encoded flow cytometry that imaged the cells in a linear flow without artificial staining. By matching the simulated patterns to confocal images of the cells, this method could be used for measuring cell morphology in three dimensions and for studying their physiology. PMID:26600999

  11. Method for determining properties of red blood cells

    DOEpatents

    Gourley, Paul L.

    2001-01-01

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

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

    PubMed

    Westerman, Maxwell; Porter, John B

    2016-07-01

    The red blood cell (RBC) is historically the original parent cell of microparticles (MPs). In this overview, we describe the discovery and the early history of red cell-derived microparticles (RMPs) and present an overview of the evolution of RMP. We report the formation, characteristics, effects of RMP and factors which may affect RMP evaluation. The review examines RMP derived from both normal and pathologic RBC. The pathologic RBC studies include sickle cell anemia (SCA), sickle cell trait (STr), thalassemia intermedia (TI), hereditary spherocytosis (HS), hereditary elliptocytosis (HE), hereditary stomatocytosis (HSt) and glucose-6-phosphate dehydrogenase deficiency (G6PD). PMID:27282583

  13. The Effect of Shape Memory on Red Blood Cell Motions

    NASA Astrophysics Data System (ADS)

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

    2013-11-01

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

  14. Gold nanoparticle-packed microdisks for multiplex Raman labelling of cells.

    PubMed

    Zhang, Peipei; Xia, Junfei; Wang, Zhibin; Guan, Jingjiao

    2014-08-01

    Micro/nanoparticles containing densely packed gold nanoparticles (AuNPs) possess unique properties potentially useful for various biomedical applications. The micro/nanoparticles are conventionally produced by the bottom-up methods, which have limited capability for controlling the particle size, shape and structure. This article reports development of a top-down method that integrates layer-by-layer assembly and microcontact printing to fabricate disk-shaped microparticles named microdisks composed of densely packed AuNPs. This method allows precise control of not only the size, shape and structure of the microdisks but also the amount of the AuNPs in the microdisks. The microdisks can be loaded with different Raman reporters to generate characteristic surface-enhanced Raman scattering spectra under the near infrared excitation over a centimetre-scale lens-sample distance. Moreover, the microdisks can be attached to single live cells. This microdisk platform holds potential for multiplex Raman labelling of therapeutic cells for in vivo tracking of the cells.

  15. Theory of the sphering of red blood cells.

    PubMed

    Fung, Y C; Tong, P

    1968-02-01

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

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

    SciTech Connect

    Srivastava, S.C.

    1983-01-01

    Radionuclidic labels for red cells can be divided into two main categories - cohort or pulse labels, and random labels. The random labels are incorporated into circulating cells of all ages and the labeling process is usually carried out in vitro. The red cell labels in predominant use involve random labeling and employ technetium-99m, chromium-51, indium-111, and gallium-68, roughly in that order. The extent of usefulness depends on the properties of the label such as the half-life, decay mode, and in-vivo stability, etc. Labeled cells can be used for red cell survival measurements when the half-life of the radionuclide is sufficiently long. The major portion of this article deals with random labels.

  17. [Consideration on high gradient magnetic separation of red cells].

    PubMed

    Iacob, Gh; Ciochină, Al D; Herea, D D; Dimitriu, Cristina; Chiruţă, Roxana; Vieru, Cristina; Stratone, Ana

    2004-01-01

    The red cells exhibit a proper magnetism due to hemoglobin. In a prototype of high gradient magnetic separator equipped with an ordered ferromagnetic matrix, a set of experiments with blood to determine the influence of the process parameters on the efficiency of the erythrocytes capture was realized. Dependent on the values of the magnetic induction (1.76-2.01 T), average blood flow velocity through the matrix (0.55-1.1 mm/s), and stationary time in the matrix, different values of concentration for the red cells in the matrix were obtained. For tests realized with integral blood, the concentration was approximately 20%, while for tests with diluted blood the concentration fluctuated from 14.51% to 29.90%. A blood recirculation through the matrix led to a concentration of 37.86%. The magnetic separation method permits an acceptable red cells concentration, without apparent destructive effects on the cells.

  18. Charge Generation Dynamics in Efficient All-Polymer Solar Cells: Influence of Polymer Packing and Morphology.

    PubMed

    Gautam, Bhoj R; Lee, Changyeon; Younts, Robert; Lee, Wonho; Danilov, Evgeny; Kim, Bumjoon J; Gundogdu, Kenan

    2015-12-23

    All-polymer solar cells exhibit rapid progress in power conversion efficiency (PCE) from 2 to 7.7% over the past few years. While this improvement is primarily attributed to efficient charge transport and balanced mobility between the carriers, not much is known about the charge generation dynamics in these systems. Here we measured exciton relaxation and charge separation dynamics using ultrafast spectroscopy in polymer/polymer blends with different molecular packing and morphology. These measurements indicate that preferential face-on configuration with intermixed nanomorphology increases the charge generation efficiency. In fact, there is a direct quantitative correlation between the free charge population in the ultrafast time scales and the external quantum efficiency, suggesting not only the transport but also charge generation is key for the design of high performance all polymer solar cells. PMID:26630116

  19. Charge Generation Dynamics in Efficient All-Polymer Solar Cells: Influence of Polymer Packing and Morphology.

    PubMed

    Gautam, Bhoj R; Lee, Changyeon; Younts, Robert; Lee, Wonho; Danilov, Evgeny; Kim, Bumjoon J; Gundogdu, Kenan

    2015-12-23

    All-polymer solar cells exhibit rapid progress in power conversion efficiency (PCE) from 2 to 7.7% over the past few years. While this improvement is primarily attributed to efficient charge transport and balanced mobility between the carriers, not much is known about the charge generation dynamics in these systems. Here we measured exciton relaxation and charge separation dynamics using ultrafast spectroscopy in polymer/polymer blends with different molecular packing and morphology. These measurements indicate that preferential face-on configuration with intermixed nanomorphology increases the charge generation efficiency. In fact, there is a direct quantitative correlation between the free charge population in the ultrafast time scales and the external quantum efficiency, suggesting not only the transport but also charge generation is key for the design of high performance all polymer solar cells.

  20. Microbial desalination cells packed with ion-exchange resin to enhance water desalination rate.

    PubMed

    Morel, Alexandre; Zuo, Kuichang; Xia, Xue; Wei, Jincheng; Luo, Xi; Liang, Peng; Huang, Xia

    2012-08-01

    A novel configuration of microbial desalination cell (MDC) packed with ion-exchange resin (R-MDC) was proposed to enhance water desalination rate. Compared with classic MDC (C-MDC), an obvious increase in desalination rate (DR) was obtained by R-MDC. With relatively low concentration (10-2 g/L NaCl) influents, the DR values of R-MDC were about 1.5-8 times those of C-MDC. Ion-exchange resins packed in the desalination chamber worked as conductor and thus counteracted the increase in ohmic resistance during treatment of low concentration salt water. Ohmic resistances of R-MDC stabilized at 3.0-4.7 Ω. By contrast, the ohmic resistances of C-MDC ranged from 5.5 to 12.7 Ω, which were 55-272% higher than those of R-MDC. Remarkable improvement in desalination rate helped improve charge efficiency for desalination in R-MDC. The results first showed the potential of R-MDC in the desalination of water with low salinity.

  1. Power generation by packed-bed air-cathode microbial fuel cells.

    PubMed

    Zhang, Xiaoyuan; Shi, Juan; Liang, Peng; Wei, Jincheng; Huang, Xia; Zhang, Chuanyi; Logan, Bruce E

    2013-08-01

    Catalysts and catalyst binders are significant portions of the cost of microbial fuel cell (MFC) cathodes. Many materials have been tested as aqueous cathodes, but air-cathodes are needed to avoid energy demands for water aeration. Packed-bed air-cathodes were constructed without expensive binders or diffusion layers using four inexpensive carbon-based materials. Cathodes made from activated carbon produced the largest maximum power density of 676 ± 93 mW/m(2), followed by semi-coke (376 ± 47 mW/m(2)), graphite (122 ± 14 mW/m(2)) and carbon felt (60 ± 43 mW/m(2)). Increasing the mass of activated carbon and semi-coke from 5 to ≥ 15 g significantly reduced power generation because of a reduction in oxygen transfer due to a thicker water layer in the cathode (∼3 or ∼6 cm). These results indicate that a thin packed layer of activated carbon or semi-coke can be used to make inexpensive air-cathodes for MFCs. PMID:23732924

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

    NASA Astrophysics Data System (ADS)

    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.

  3. Target analysis studies of red cell water and urea transport.

    PubMed

    Dix, J A; Ausiello, D A; Jung, C Y; Verkman, A S

    1985-12-01

    Radiation inactivation was used to determine the nature and molecular weight of water and urea transporters in the human red cell. Red cells were frozen to -50 degrees C in a cryoprotectant solution, irradiated with 1.5 MeV electrons, thawed, washed and assayed for osmotic water and urea permeability by stopped-flow light scattering. The freezing and thawing process did not affect the rates of water or urea transport or the inhibitory potency of p-chloromercuribenzenesulfonate (pCMBS) on water transport and of phloretin on urea transport. Red cell urea transport inactivated with radiation (0-4 Mrad) with a single target size of 469 +/- 36 kDa. 40 microM phloretin inhibited urea flux by approx. 50% at each radiation dose, indicating that urea transporters surviving radiation were inhibitable. Water transport did not inactivate with radiation; however, the inhibitory potency of 2.5 mM pCMBS decreased from 86 +/- 1% to 4 +/- 9% over a 0-2 Mrad dose range. These studies suggest that red cell water transport either required one or more low-molecular-weight proteins, or is lipid-mediated, and that the pCMBS-binding site which regulates water flow inactivates with radiation. These results also suggest that red cell urea transport is mediated by a specific, high-molecular-weight protein. These results do not support the hypothesis that a band 3 dimer (190 kDa) mediates red cell osmotic water and urea transport. PMID:2998469

  4. Techniques for measuring red cell, platelet, and WBC survival

    SciTech Connect

    Mayer, K.; Freeman, J.E.

    1986-01-01

    Blood cell survival studies yield valuable information concerning production and destruction of cells circulating in the bloodstream. Methodologies for the measurement of red cell survival include nonisotopic methods such as differential agglutination and hemolysis. The isotopic label may be radioactive or, if not, will require availability of a mass spectrograph. These methods fall into two categories, one where red cells of all ages are labeled (/sup 51/Cr, DFP32, etc.) and those employing a cohort label of newly formed cells (/sup 14/C glycine, /sup 75/Se methionine, etc.). Interpretation of results for methodology employed and mechanism of destruction, random or by senescence, are discussed. A similar approach is presented for platelet and leukocyte survival studies. The inherent difficulties and complications of sequestration, storage, and margination of these cells are emphasized and discussed. 38 references.

  5. Morphological changes in neutron irradiated red blood cells.

    PubMed

    Nelson, A C; Wyle, H R

    1985-01-01

    Living human red blood cells (erythrocytes) were irradiated with a beam of thermal neutrons having a thermal neutron flux of 9.4 X 10(9) neutrons/cm2 per sec corresponding to a dose rate of 5 Gray per hour. The neutron beam was obtained from the thermal neutron facility at the MIT Nuclear Reactor and contained some gamma-ray contamination which contributes approximately 8% of the dose effect. Approximately 92% of the dose effect is due to the neutron radiation. Populations of neutron irradiated red blood cells were examined under scanning electron microscopy to observe morphological changes due to the radiation dose. The thermal neutron doses ranged from zero for controls to 75 Gray, and cell populations were examined at various post-irradiation time periods of 10, 48, and 96 h. A four-stage discoid to spheroid shape transformation of the damaged red blood cells was characterized, and the time dependence of each transformation stage was determined for both unirradiated and irradiated cells. The radiation dose caused an initial dose-dependent shift from Stage 1 to Stage 2 with an associated increase in the transformation rate constants. The thermal neutron doses delivered are considered to be in the low dose range for radiation effects on red blood cells, yet the pronounced effects indicate a high relative biological effectiveness (RBE) for thermal neutrons.

  6. Photoacoustic response of suspended and hemolyzed red blood cells

    NASA Astrophysics Data System (ADS)

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

    2013-07-01

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

  7. Exploratory design in medical nanotechnology: a mechanical artificial red cell.

    PubMed

    Freitas, R A

    1998-07-01

    Molecular manufacturing promises precise control of matter at the atomic and molecular level, allowing the construction of micron-scale machines comprised of nanometer-scale components. Medical nanomachines will be among the earliest applications. The artificial red blood cell or "respirocyte" proposed here is a bloodborne spherical 1-micron diamondoid 1000-atm pressure vessel with active pumping powered by endogenous serum glucose, able to deliver 236 times more oxygen to the tissues per unit volume than natural red cells and to manage carbonic acidity. An onboard nanocomputer and numerous chemical and pressure sensors enable complex device behaviors remotely reprogrammable by the physician via externally applied acoustic signals.

  8. Size-topology relations in packings of grains, emulsions, foams, and biological cells.

    PubMed

    Newhall, K A; Pontani, L L; Jorjadze, I; Hilgenfeldt, S; Brujic, J

    2012-06-29

    Particulate packings in 3D are used to study the effects of compression and polydispersity on the geometry of the tiling in these systems. We find that the dependence of the neighbor number on cell size is quasilinear in the monodisperse case and becomes nonlinear above a threshold polydispersity, independent of the method of creation of the tiling. These size-topology relations can be described by a simple analytical theory, which quantifies the effects of positional disorder in the monodisperse case and those of size disorder in the polydisperse case and is applicable in two and three dimensions. The theory thus gives a unifying framework for a wide range of amorphous systems, ranging from biological tissues, foams, and bidisperse disks to compressed emulsions and granular matter. PMID:23005016

  9. Anatomy of the red cell membrane skeleton: unanswered questions.

    PubMed

    Lux, Samuel E

    2016-01-14

    The red cell membrane skeleton is a pseudohexagonal meshwork of spectrin, actin, protein 4.1R, ankyrin, and actin-associated proteins that laminates the inner membrane surface and attaches to the overlying lipid bilayer via band 3-containing multiprotein complexes at the ankyrin- and actin-binding ends of spectrin. The membrane skeleton strengthens the lipid bilayer and endows the membrane with the durability and flexibility to survive in the circulation. In the 36 years since the first primitive model of the red cell skeleton was proposed, many additional proteins have been discovered, and their structures and interactions have been defined. However, almost nothing is known of the skeleton's physiology, and myriad questions about its structure remain, including questions concerning the structure of spectrin in situ, the way spectrin and other proteins bind to actin, how the membrane is assembled, the dynamics of the skeleton when the membrane is deformed or perturbed by parasites, the role lipids play, and variations in membrane structure in unique regions like lipid rafts. This knowledge is important because the red cell membrane skeleton is the model for spectrin-based membrane skeletons in all cells, and because defects in the red cell membrane skeleton underlie multiple hemolytic anemias.

  10. 7 CFR 51.310 - Packing requirements.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... STANDARDS) United States Standards for Grades of Apples Packing Requirements § 51.310 Packing requirements. (a) Apples tray packed or cell packed in cartons shall be arranged according to approved and... that apples are of the proper size for molds or cell compartments in which they are packed, and...

  11. 7 CFR 51.310 - Packing requirements.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... STANDARDS) United States Standards for Grades of Apples Packing Requirements § 51.310 Packing requirements. (a) Apples tray packed or cell packed in cartons shall be arranged according to approved and... that apples are of the proper size for molds or cell compartments in which they are packed, and...

  12. 7 CFR 51.310 - Packing requirements.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... STANDARDS) United States Standards for Grades of Apples Packing Requirements § 51.310 Packing requirements. (a) Apples tray packed or cell packed in cartons shall be arranged according to approved and... that apples are of the proper size for molds or cell compartments in which they are packed, and...

  13. Mesenchymal progenitor cells in red and yellow bone marrow.

    PubMed

    Gurevitch, O; Slavin, S; Resnick, I; Khitrin, S; Feldman, A

    2009-01-01

    Marrow cavities in all bones of newborn mammals contain haematopoietic tissue and stromal microenvironment that support haematopoiesis (haematopoietic microenvironment), known as red bone marrow (BM). From the early postnatal period onwards, the haematopoietic microenvironment, mainly in tubular bones of the extremities, is replaced by mesenchymal cells that accumulate lipid drops, known as yellow BM, whereas haematopoietic tissue gradually disappears. We analysed the ability of mesenchymal cell progenitors in red and yellow BM to produce bone and haematopoietic microenvironment in vivo after transplantation into normal or haematopoietically deficient (irradiated and old) recipients. We found that (1) normal substitution of red with yellow BM results from a gradual loss of mesenchymal stem cells (MSCs) capable of developing bone and haematopoietic microenvironment; (2) the mesenchymal cell population in tubular bones still containing active haematopoietic tissue gradually becomes depleted of MSCs, starting from a young age; (3) haematopoietic microenvironment is incapable of self-maintenance and its renewal depends on the presence of precursor cells; (4) the mesenchymal cell population remaining in areas with yellow BM contains cells able to develop functionally active haematopoietic microenvironment in conditions of haematopoietic insufficiency. Our data also indicate the possible existence of bi-potential stromal precursor cells producing either bone in normal, or bone together with active haematopoietic microenvironment in irradiated or old recipients. This study opens a spectrum of opportunities for the extension of haematopoietic territories by substituting the fat contents of BM cavities with haematopoietic tissue, thereby improving haematopoiesis compromised by cytotoxic treatments, irradiation, ageing, etc.

  14. Involvement of ligninolytic enzymes of Phanerochaete chrysosporium in treating the textile effluent containing Astrazon Red FBL in a packed-bed bioreactor.

    PubMed

    Sedighi, M; Karimi, A; Vahabzadeh, F

    2009-09-30

    The effect of Tween80, Mn(II) and veratryl alcohol (VA) on the production of ligninolytic enzymes of Phanerochaete chrysosporium in a packed-bed bioreactor using small pieces of Kissiris as carrier, was investigated. The results of the enzyme activities were noticeable in terms of decolorization and COD removal of the textile effluent containing an azo dye (Astrazon Red FBL). No dilution was made on the tested textile effluent and it was not sterilized, also. Maximum decolorization of the dye (87%) and COD removal (42%), both occurred when only Tween80 (0.05%, w/v) was added to the effluent. The maximum activities of lignin peroxidase (LiP) and manganese peroxidase (MnP) were (U/l): 17 and 52, respectively. The role of MnP was pronounced in the dye decolorization process, while the influence of LiP was noticeable on COD removal. The reusability of the original biomass was examined by replacing undiluted textile effluent (i.e., five times). The cellular performance of the original biomass in repeated-batch operations was promising.

  15. Enhanced desalination performance of membrane capacitive deionization cells by packing the flow chamber with granular activated carbon.

    PubMed

    Bian, Yanhong; Yang, Xufei; Liang, Peng; Jiang, Yong; Zhang, Changyong; Huang, Xia

    2015-11-15

    A new design of membrane capacitive deionization (MCDI) cell was constructed by packing the cell's flow chamber with granular activated carbon (GAC). The GAC packed-MCDI (GAC-MCDI) delivered higher (1.2-2.5 times) desalination rates than the regular MCDI at all test NaCl concentrations (∼ 100-1000 mg/L). The greatest performance enhancement by packed GAC was observed when treating saline water with an initial NaCl concentration of 100 mg/L. Several different GAC materials were tested and they all exhibited similar enhancement effects. Comparatively, packing the MCDI's flow chamber with glass beads (GB; non-conductive) and graphite granules (GG; conductive but with lower specific surface area than GAC) resulted in inferior desalination performance. Electrochemical impedance spectroscopy (EIS) analysis showed that the GAC-MCDI had considerably smaller internal resistance than the regular MCDI (∼ 19.2 ± 1.2 Ω versus ∼ 1222 ± 15 Ω at 100 mg/L NaCl). The packed GAC also decreased the ionic resistance across the flow chamber (∼ 1.49 ± 0.05 Ω versus ∼ 1130 ± 12 Ω at 100 mg/L NaCl). The electric double layer (EDL) formed on the GAC surface was considered to store salt ions during electrosorption, and facilitate the ion transport in the flow chamber because of the higher ion conductivity in the EDLs than in the bulk solution, thereby enhancing the MCDI's desalination rate.

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

    PubMed

    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.

  17. Transbilayer mobility and distribution of red cell phospholipids during storage.

    PubMed Central

    Geldwerth, D; Kuypers, F A; Bütikofer, P; Allary, M; Lubin, B H; Devaux, P F

    1993-01-01

    We studied phospholipid topology and transbilayer mobility in red cells during blood storage. The distribution of phospholipids was determined by measuring the reactivity of phosphatidylethanolamine with fluorescamine and the degradation of phospholipids by phospholipase A2 and sphingomyelinase C. Phospholipid mobility was measured by determining transbilayer movements of spin-labeled phospholipids. We were unable to detect a change in the distribution of endogenous membrane phospholipids in stored red cells even after 2-mo storage. The rate of inward movement of spin-labeled phosphatidylethanolamine and phosphatidylserine was progressively reduced, whereas that for phosphatidylcholine was increased. These changes in phospholipid translocation correlated with a fall in cellular ATP. However, following restoration of ATP, neither the rate of aminophospholipid translocation nor the transbilayer movement of phosphatidylcholine were completely corrected. Taken together, our findings demonstrate that red cell storage alters the kinetics of transbilayer mobility of phosphatidylserine, phosphatidylethanolamine, and phosphatidylcholine, the activity of the aminophospholipid translocase, but not the asymmetric distribution of endogenous membrane phospholipids, at least at a level detectable with phospholipases. Thus, if phosphatidylserine appearance on the outer monolayer is a signal for red cell elimination, the amount that triggers macrophage recognition is below the level of detection upon using the phospholipase technique. PMID:8325999

  18. Automated microbiological assay of thiamin in serum and red cells.

    PubMed Central

    Icke, G; Nicol, D

    1994-01-01

    AIMS--To develop a sensitive, direct, automated method for the measurement of serum and red cell thiamin. METHODS--A microbiological assay using a chloramphenicol resistant strain of Lactobacillus fermenti as the test organism was developed. Addition of chloramphenicol and cycloheximide to the assay medium suppressed bacterial and yeast contamination and enabled tests to be automated without recourse to aseptic procedures. Evaluation of the assay included precision analysis and estimation of thiamin recovery. Results obtained on red cell extracts were compared with an established colorimetric (thiochrome) method. RESULTS--Acceptable intrabatch and interbatch precision was obtained and good recovery of thiamin added to serum was obtained. Non-parametric reference ranges based on the results from 505 healthy people were: serum thiamin 11.3-35.0 nmol/l and red cell thiamin 190-400 nmol/l. Results were not age or gender related. The method gave results for red cell thiamin which were significantly higher than those obtained with an established thiochrome method. CONCLUSIONS--This automated microbiological assay is sensitive to 2.0 nmol/l of thiamin and allows tests to be set up at the rate of 100 per hour and after 20-22 hours allows incubation results to be read at 60 per hour. The method has proved reliable, suitable for the assay of large numbers of samples, and relatively inexpensive to perform. PMID:8089221

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

    PubMed

    Dupire, Jules; Socol, Marius; Viallat, Annie

    2012-12-18

    At the cellular scale, blood fluidity and mass transport depend on the dynamics of red blood cells in blood flow, specifically on their deformation and orientation. These dynamics are governed by cellular rheological properties, such as internal viscosity and cytoskeleton elasticity. In diseases in which cell rheology is altered genetically or by parasitic invasion or by changes in the microenvironment, blood flow may be severely impaired. The nonlinear interplay between cell rheology and flow may generate complex dynamics, which remain largely unexplored experimentally. Under simple shear flow, only two motions, "tumbling" and "tank-treading," have been described experimentally and relate to cell mechanics. Here, we elucidate the full dynamics of red blood cells in shear flow by coupling two videomicroscopy approaches providing multidirectional pictures of cells, and we analyze the mechanical origin of the observed dynamics. We show that contrary to common belief, when red blood cells flip into the flow, their orientation is determined by the shear rate. We discuss the "rolling" motion, similar to a rolling wheel. This motion, which permits the cells to avoid energetically costly deformations, is a true signature of the cytoskeleton elasticity. We highlight a hysteresis cycle and two transient dynamics driven by the shear rate: an intermittent regime during the "tank-treading-to-flipping" transition and a Frisbee-like "spinning" regime during the "rolling-to-tank-treading" transition. Finally, we reveal that the biconcave red cell shape is highly stable under moderate shear stresses, and we interpret this result in terms of stress-free shape and elastic buckling. PMID:23213229

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

    PubMed

    Chang, Thomas Ming Swi

    2015-06-01

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

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

    PubMed

    Chang, Thomas Ming Swi

    2015-06-01

    Why is this important? Under normal circumstances, donor blood is the best replacement for blood. However, there are exceptions: During natural epidemics (e.g., HIV, Ebola, etc.) or man-made epidemics (terrorism, war, etc.), there is a risk of donor blood being contaminated, and donors being disqualified because they have contracted disease. Unlike red blood cells (RBCs), blood substitutes can be sterilized to remove infective agents. Heart attack and stroke are usually caused by obstruction of arterial blood vessels. Unlike RBCs, which are particulate, blood substitutes are in the form of a solution that can perfuse through obstructed vessels with greater ease to reach the heart and brain, as has been demonstrated in animal studies. Severe blood loss from injuries sustained during accidents, disasters, or war may require urgent blood transfusion that cannot wait for transportation to the hospital for blood group testing. Unlike RBCs, blood substitutes do not have specific blood groups, and can be administered on the spot. RBCs have to be stored under refrigeration for up to 42 days, and are thus difficult to transport and store in times of disaster and at the battlefront. Blood substitutes can be stored at room temperature for more than 1 year, compared to the RBC shelf life of 1 day, at room temperature. In cases of very severe hemorrhagic shock, there is usually a safety window of 60 min for blood replacement, beyond which there could be problems related to irreversible shock. Animal studies show that a particular type of blood substitute, with enhanced RBC enzymes, may be able to prolong the duration of the safety window. PMID:26096663

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

    PubMed

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

    1987-06-01

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

  3. Red Blood Cell Polymorphism and Susceptibility to Plasmodium vivax

    PubMed Central

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

    2013-01-01

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

  4. Red blood cell and iron metabolism during space flight

    NASA Technical Reports Server (NTRS)

    Smith, Scott M.

    2002-01-01

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

  5. Reducing red cell transfusion by audit, education and a new guideline in a large teaching hospital.

    PubMed

    Garrioch, M; Sandbach, J; Pirie, E; Morrison, A; Todd, A; Green, R

    2004-02-01

    Safety concerns combined with the greatly increased costs and difficulties of maintaining the blood supply are major considerations for transfusion services. Previous local surveys demonstrated that hospital blood use at our hospital could be improved. Excessive cross-matching, unnecessary transfusion and high return rates of unused blood were commonplace. Transfusion practice was audited over a 3-month period. An education package with guidelines for transfusion was delivered to all clinician groups within the hospital, over the following 9 months. The audit was repeated exactly 1 year later at the same time period. During the second audit, inpatient hospital numbers increased by 1.02% (from n = 7262 to n = 7336) but no differences in length of stay, cardiovascular morbidity or mortality were demonstrated. Twenty percent (n = 254, 2002; n = 316, 2001) fewer patients received blood, and the number of red cell packs used reduced by 19% (from n = 1093 to n = 880). Total number of patients transfused reduced from 4.4% to 3.5% which, as an absolute difference, is a reduction of 0.9% (CI 0.3-1.5, P = 0.006). The audit, guideline and education package had a major impact on red cell use within the hospital with no adverse effects. Blood use can be improved by the implementation of a suitable education package and guideline. If it is possible to replicate the results of this education programme nationwide, the effect on blood use, with subsequent savings and enhanced patient safety could be significant.

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

    NASA Astrophysics Data System (ADS)

    Lee, Seungjun; Lu, Wei

    2011-08-01

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

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

    PubMed Central

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

    2012-01-01

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

  8. Intracellular energetic units in red muscle cells.

    PubMed Central

    Saks, V A; Kaambre, T; Sikk, P; Eimre, M; Orlova, E; Paju, K; Piirsoo, A; Appaix, F; Kay, L; Regitz-Zagrosek, V; Fleck, E; Seppet, E

    2001-01-01

    The kinetics of regulation of mitochondrial respiration by endogenous and exogenous ADP in muscle cells in situ was studied in skinned cardiac and skeletal muscle fibres. Endogenous ADP production was initiated by addition of MgATP; under these conditions the respiration rate and ADP concentration in the medium were dependent on the calcium concentration, and 70-80% of maximal rate of respiration was achieved at ADP concentration below 20 microM in the medium. In contrast, when exogenous ADP was added, maximal respiration rate was observed only at millimolar concentrations. An exogenous ADP-consuming system consisting of pyruvate kinase (PK; 20-40 units/ml) and phosphoenolpyruvate (PEP; 5 mM), totally suppressed respiration activated by exogenous ADP, but the respiration maintained by endogenous ADP was not suppressed by more than 20-40%. Creatine (20 mM) further activated respiration in the presence of ATP and PK+PEP. Short treatment with trypsin (50-500 nM for 5 min) decreased the apparent K(m) for exogenous ADP from 300-350 microM to 50-60 microM, increased inhibition of respiration by PK+PEP system up to 70-80%, with no changes in MgATPase activity and maximal respiration rates. Electron-microscopic observations showed detachment of mitochondria and disordering of the regular structure of the sarcomere after trypsin treatment. Two-dimensional electrophoresis revealed a group of at least seven low-molecular-mass proteins in cardiac skinned fibres which were very sensitive to trypsin and not present in glycolytic fibres, which have low apparent K(m) for exogenous ADP. It is concluded that, in oxidative muscle cells, mitochondria are incorporated into functional complexes ('intracellular energetic units') with adjacent ADP-producing systems in myofibrils and in sarcoplasmic reticulum, probably due to specific interaction with cytoskeletal elements responsible for mitochondrial distribution in the cell. It is suggested that these complexes represent the basic

  9. Membranotropic photobiomodulation on red blood cell deformability

    NASA Astrophysics Data System (ADS)

    Luo, Gang-Yue; Zhao, Yan-Ping; Liu, Timon C.; Liu, Song-Hao

    2007-05-01

    To assess modulation of laser on erythrocyte permeability and deformability via cell morphology changes, healthy human echinocytes with shrinking size and high plasmic viscosity due to cellular dehydration were treated with 1 mW, 2 mW, 3 mW, and 5 mW laser power exposure respectively. Image analyzing system on single intact erythrocyte was applied for measuring comprehensive cell morphological parameters (surface area, external membrane perimeter, circle index and elongation index) that were determined by the modulation of erythrocyte water permeability and deformability to detect relationship between erythrocyte water permeability alteration and deformability. Our preliminary experiment showed that exposure under light dose of 5 mW for 5 min could induce more active erythrocyte swelling and deformation. water channel aquaporin-1(AQP-1) was inhibited by the incubation of HgCl II in the presence and absence of 5 mW laser irradiation. The result suggested that osmotic water permeability is a primary factor in the procedure of erythrocyte deformability. In addition, no modulation of laser(5mW) on erythrocyte deformability had been found when the echinocytes were cultured with GDP-β-S (G protein inhibitor).

  10. Alterations of red cell membrane properties in neuroacanthocytosis.

    PubMed

    Siegl, Claudia; Hamminger, Patricia; Jank, Herbert; Ahting, Uwe; Bader, Benedikt; Danek, Adrian; Gregory, Allison; Hartig, Monika; Hayflick, Susan; Hermann, Andreas; Prokisch, Holger; Sammler, Esther M; Yapici, Zuhal; Prohaska, Rainer; Salzer, Ulrich

    2013-01-01

    Neuroacanthocytosis (NA) refers to a group of heterogenous, rare genetic disorders, namely chorea acanthocytosis (ChAc), McLeod syndrome (MLS), Huntington's disease-like 2 (HDL2) and pantothenate kinase associated neurodegeneration (PKAN), that mainly affect the basal ganglia and are associated with similar neurological symptoms. PKAN is also assigned to a group of rare neurodegenerative diseases, known as NBIA (neurodegeneration with brain iron accumulation), associated with iron accumulation in the basal ganglia and progressive movement disorder. Acanthocytosis, the occurrence of misshaped erythrocytes with thorny protrusions, is frequently observed in ChAc and MLS patients but less prevalent in PKAN (about 10%) and HDL2 patients. The pathological factors that lead to the formation of the acanthocytic red blood cell shape are currently unknown. The aim of this study was to determine whether NA/NBIA acanthocytes differ in their functionality from normal erythrocytes. Several flow-cytometry-based assays were applied to test the physiological responses of the plasma membrane, namely drug-induced endocytosis, phosphatidylserine exposure and calcium uptake upon treatment with lysophosphatidic acid. ChAc red cell samples clearly showed a reduced response in drug-induced endovesiculation, lysophosphatidic acid-induced phosphatidylserine exposure, and calcium uptake. Impaired responses were also observed in acanthocyte-positive NBIA (PKAN) red cells but not in patient cells without shape abnormalities. These data suggest an "acanthocytic state" of the red cell where alterations in functional and interdependent membrane properties arise together with an acanthocytic cell shape. Further elucidation of the aberrant molecular mechanisms that cause this acanthocytic state may possibly help to evaluate the pathological pathways leading to neurodegeneration. PMID:24098554

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

    NASA Technical Reports Server (NTRS)

    Johnson, P. C., Jr.

    1973-01-01

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

  12. Oriented cell division affects the global stress and cell packing geometry of a monolayer under stretch.

    PubMed

    Xu, Guang-Kui; Liu, Yang; Zheng, Zhaoliang

    2016-02-01

    Cell division plays a vital role in tissue morphogenesis and homeostasis, and the division plane is crucial for cell fate. For isolated cells, extensive studies show that the orientation of divisions is sensitive to cell shape and the direction of extrinsic mechanical forces. However, it is poorly understood that how the cell divides within a cell monolayer and how the local stress change, due to the division, affects the global stress of epithelial monolayers. Here, we use the vertex dynamics models to investigate the effects of division orientation on the configurations and mechanics of a cell monolayer under stretch. We examine three scenarios of the divisions: dividing along the stretch axis, dividing along the geometric long axis of cells, and dividing at a random angle. It is found that the division along the long cell axis can induce the minimal energy difference, and the global stress of the monolayer after stretch releases more rapidly in this case. Moreover, the long-axis division can result in more random cell orientations and more isotropic cell shapes within the monolayer, comparing with other two cases. This study helps understand the division orientation of cells within a monolayer under mechanical stimuli, and may shed light on linking individual cell's behaviors to the global mechanics and patterns of tissues. PMID:26774292

  13. Oriented cell division affects the global stress and cell packing geometry of a monolayer under stretch.

    PubMed

    Xu, Guang-Kui; Liu, Yang; Zheng, Zhaoliang

    2016-02-01

    Cell division plays a vital role in tissue morphogenesis and homeostasis, and the division plane is crucial for cell fate. For isolated cells, extensive studies show that the orientation of divisions is sensitive to cell shape and the direction of extrinsic mechanical forces. However, it is poorly understood that how the cell divides within a cell monolayer and how the local stress change, due to the division, affects the global stress of epithelial monolayers. Here, we use the vertex dynamics models to investigate the effects of division orientation on the configurations and mechanics of a cell monolayer under stretch. We examine three scenarios of the divisions: dividing along the stretch axis, dividing along the geometric long axis of cells, and dividing at a random angle. It is found that the division along the long cell axis can induce the minimal energy difference, and the global stress of the monolayer after stretch releases more rapidly in this case. Moreover, the long-axis division can result in more random cell orientations and more isotropic cell shapes within the monolayer, comparing with other two cases. This study helps understand the division orientation of cells within a monolayer under mechanical stimuli, and may shed light on linking individual cell's behaviors to the global mechanics and patterns of tissues.

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

    DOEpatents

    Bitensky, Mark W.

    1995-01-01

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

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

    DOEpatents

    Bitensky, M.W.

    1995-12-19

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

  16. Online biomedical resources for malaria-related red cell disorders.

    PubMed

    Piel, Frédéric B; Howes, Rosalind E; Nyangiri, Oscar A; Moyes, Catherine L; Williams, Thomas N; Weatherall, David J; Hay, Simon I

    2013-07-01

    Warnings about the expected increase of the global public health burden of malaria-related red cell disorders are accruing. Past and present epidemiological data are necessary to track spatial and temporal changes in the frequencies of these genetic disorders. A number of open access biomedical databases including data on malaria-related red cell disorders have been launched over the last two decades. Here, we review the content of these databases, most of which focus on genetic diversity, and we describe a new epidemiological resource developed by the Malaria Atlas Project. To tackle upcoming public health challenges, the integration of epidemiological and genetic data is important. As many countries are considering implementing national screening programs, strategies to make such data more accessible are also needed.

  17. Online Biomedical Resources for Malaria-Related Red Cell Disorders

    PubMed Central

    Piel, Frédéric B; Howes, Rosalind E; Nyangiri, Oscar A; Moyes, Catherine L; Williams, Thomas N; Weatherall, David J; Hay, Simon I

    2013-01-01

    Warnings about the expected increase of the global public health burden of malaria-related red cell disorders are accruing. Past and present epidemiological data are necessary to track spatial and temporal changes in the frequencies of these genetic disorders. A number of open access biomedical databases including data on malaria-related red cell disorders have been launched over the last two decades. Here, we review the content of these databases, most of which focus on genetic diversity, and we describe a new epidemiological resource developed by the Malaria Atlas Project. To tackle upcoming public health challenges, the integration of epidemiological and genetic data is important. As many countries are considering implementing national screening programs, strategies to make such data more accessible are also needed. PMID:23568771

  18. Online biomedical resources for malaria-related red cell disorders.

    PubMed

    Piel, Frédéric B; Howes, Rosalind E; Nyangiri, Oscar A; Moyes, Catherine L; Williams, Thomas N; Weatherall, David J; Hay, Simon I

    2013-07-01

    Warnings about the expected increase of the global public health burden of malaria-related red cell disorders are accruing. Past and present epidemiological data are necessary to track spatial and temporal changes in the frequencies of these genetic disorders. A number of open access biomedical databases including data on malaria-related red cell disorders have been launched over the last two decades. Here, we review the content of these databases, most of which focus on genetic diversity, and we describe a new epidemiological resource developed by the Malaria Atlas Project. To tackle upcoming public health challenges, the integration of epidemiological and genetic data is important. As many countries are considering implementing national screening programs, strategies to make such data more accessible are also needed. PMID:23568771

  19. Automation of cross-matching and red cell antibody screening.

    PubMed

    Wattar, B; Lambermont, M; Govaerts, A

    1982-01-01

    This automatic system combines the major cross-match with screening for allo- and autoantibodies. Moreover, the detected antibodies can be identified on a panel of frozen and thawed red blood cells (RBC). The system is made up of two connected samplers, three channels working, respectively, with bromelin PVP, LISP and saline PVP at 4 degrees C, three colorimeters or three red cell autocounters and their recorders. The optimal speed is 50 samples/h and one whole test requires 19 min. Our experience indicates that this automatic system is appreciably more sensitive and much more rapid and efficient than manual techniques. In spite of increased sensitivity, the ratio of rejected bags does not exceed 2.7%. PMID:7090333

  20. Color contrast of red blood cells on solid substrate

    NASA Astrophysics Data System (ADS)

    Paiziev, Adkham A.

    2013-02-01

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

  1. Assessment of five formulae to predict post-transfusion packed cell volume in cats.

    PubMed

    Reed, Nicki; Espadas, Irene; Lalor, Stephanie M; Kisielewicz, Caroline

    2014-08-01

    This retrospective study aimed to identify the most accurate formula for estimating the increase in packed cell volume (PCV) after whole blood transfusion of cats, as several formulae have been reported but not validated. Forty cats, of varying breeds and gender, were included from two referral institutions after database searches over a 13 year period. Five formulae were used to calculate an estimated post-transfusion PCV based on the re-working of formulae for determining the volume of donor blood to be transfused; three formulae were derived from those previously reported in the feline literature and two from human paediatric medicine, where a similar mean blood volume has been described. Cats were subdivided into two groups, the first consisting of 17 cats with non-regenerative anaemia and the second consisting of 23 cats with ongoing losses such as haemolysis and haemorrhage; it was hypothesised that formulae could be more accurate for group 1 cats, whereas formulae applied to group 2 cats could have overestimated the post-transfusion PCV. Bland-Altman analysis was performed for all cats to compare the actual increase in PCV with the calculated increase for the five formulae. Formula 1 (PCV % increase = volume of blood transfused in ml/2 × bodyweight in kg) performed best overall and is easy to calculate; however, no single formula was highly accurate at predicting the PCV increase after whole blood transfusion in cats and, owing to the wide confidence intervals, these formulae should be applied judiciously in the clinical setting.

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

    NASA Astrophysics Data System (ADS)

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

    2016-04-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2016-03-01

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

  4. Effect of visible laser light on ATP level of anaemic red blood cell.

    PubMed

    Suardi, Nursakinah; Sodipo, Bashiru Kayode; Mustafa, Mohd Zulkifli; Ali, Zalila

    2016-09-01

    In this work we present influence of visible laser light on ATP level and viability of anaemic red blood cell (RBC). The visible laser lights used in this work are 460nm and 532nm. The responses of ATP level in anaemic and normal RBC before and after laser irradiation at different exposure time (30, 40, 50 and 60s) were observed. Three aliquots were prepared from the ethylenediaminetetraacetic acid (EDTA) blood sample. One served as a control (untreated) and another two were irradiated with 460nm and 560nm lasers. Packed RBC was prepared to study ATP level in the RBC using CellTiter-GloLuminescent cell Viability Assay kit. The assay generates a glow type signal produced by luciferase reaction, which is proportional to the amount of ATP present in RBCs. Paired t-test were done to analyse ATP level before and after laser irradiation. The results revealed laser irradiation improve level of ATP in anaemic RBC. Effect of laser light on anaemic RBCs were significant over different exposure time for both 460nm (p=0.000) and 532nm (p=0.003). The result of ATP level is further used as marker for RBC viability. The influence of ATP level and viability were studied. Optical densities obtained from the data were used to determine cell viability of the samples. Results showed that laser irradiation increased viability of anaemic RBC compared to normal RBC.

  5. My passion and passages with red blood cells.

    PubMed

    Hoffman, Joseph F

    2008-01-01

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

  6. Hemoglobin-based red blood cell substitutes and nitric oxide.

    PubMed

    Yu, Binglan; Bloch, Kenneth D; Zapol, Warren M

    2009-04-01

    Hemoglobin-based oxygen carriers (HBOCs) have been studied for decades as red blood cell substitutes. Profound vasoconstrictor effects have limited the clinical utility of HBOCs and are attributable to avid scavenging of nitric oxide (NO). Inhaling NO can charge the body's stores of NO metabolites without producing hypotension and can prevent systemic hypertension induced when HBOCs are subsequently infused. Concurrent breathing of low NO doses can prevent pulmonary vasoconstriction after HBOC infusion without augmenting plasma methemoglobinemia.

  7. Lysis of red blood cells and alveolar epithelial toxicity by therapeutic pulmonary surfactants.

    PubMed

    Findlay, R D; Taeusch, H W; David-Cu, R; Walther, F J

    1995-01-01

    The risk of pulmonary hemorrhage is increased in extremely low birth weight infants treated with surfactant. The pathogenesis of this increased risk is far from clear. We tested whether exposure of cell membranes to surfactant may lead to increased membrane permeability, hypothesizing that this process may contribute to the occurrence of alveolar hemorrhage after surfactant treatment. Aliquots of washed packed red blood cells (used as membrane model) were suspended in 0.9% NaCl with various concentrations of Survanta or Exosurf for either 2 or 24 h at 37 degrees C. Cytolysis was measured by spectrophotometric determination of free Hb after centrifugation. Red cells suspended in 0.9% NaCl alone, distilled water, or various concentrations of melittin were used as negative and positive controls. Both surfactants were associated with increased hemolysis to 35% of maximum at concentrations of 1.25 mg/2 mL. Above these concentrations, Survanta was associated with no increase in hemolysis, whereas Exosurf increased hemolysis to 60% of maximum at concentrations of 12.5 mg/2 mL. In additional experiments, primary cultures of alveolar type II cells from adult rats were treated with Survanta, Exosurf, the Exosurf components tyloxapol and hexadecanol, melittin, or culture medium alone. After 24 h of incubation, lactate dehydrogenase release into the media was measured as a percent of total lactate dehydrogenase activity to indicate cytotoxicity. Lactate dehydrogenase release was < 10% for control experiments but increased sharply with Exosurf and its components tyloxapol and hexadecanol. These results indicate that surfactant may be associated with in vitro cytotoxicity and that this property differs for different surfactants and different dosages.

  8. Depletion of membrane skeleton in red blood cell vesicles.

    PubMed Central

    Iglic, A; Svetina, S; Zeks, B

    1995-01-01

    A possible physical interpretation of the partial detachment of the membrane skeleton in the budding region of the cell membrane and consequent depletion of the membrane skeleton in red blood cell vesicles is given. The red blood cell membrane is considered to consist of the bilayer part and the membrane skeleton. The skeleton is, under normal conditions, bound to the bilayer over its whole area. It is shown that, when in such conditions it is in the expanded state, some cell shape changes can induce its partial detachment. The partial detachment of the skeleton from the bilayer is energetically favorable if the consequent decrease of the skeleton expansion energy is larger than the corresponding increase of the bilayer-skeleton binding energy. The effect of shape on the skeleton detachment is analyzed theoretically for a series of the pear class shapes, having decreasing neck diameter and ending with a parent-daughter pair of spheres. The partial detachment of the skeleton is promoted by narrowing of the cell neck, by increasing the lateral tension in the skeleton and its area expansivity modulus, and by diminishing the attraction forces between the skeleton and the bilayer. If the radius of the daughter vesicle is sufficiently small relative to the radius of the parent cell, the daughter vesicle can exist either completely underlaid with the skeleton or completely depleted of the skeleton. PMID:7669905

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

    NASA Astrophysics Data System (ADS)

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

    1983-06-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2010-07-01

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

  11. Red blood cell clustering in Poiseuille microcapillary flow

    NASA Astrophysics Data System (ADS)

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

    2012-05-01

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

  12. Training the next generation analyst using red cell analytics

    NASA Astrophysics Data System (ADS)

    Graham, Meghan N.; Graham, Jacob L.

    2016-05-01

    We have seen significant change in the study and practice of human reasoning in recent years from both a theoretical and methodological perspective. Ubiquitous communication coupled with advances in computing and a plethora of analytic support tools have created a push for instantaneous reporting and analysis. This notion is particularly prevalent in law enforcement, emergency services and the intelligence community (IC), where commanders (and their civilian leadership) expect not only a birds' eye view of operations as they occur, but a play-by-play analysis of operational effectiveness. This paper explores the use of Red Cell Analytics (RCA) as pedagogy to train the next-gen analyst. A group of Penn State students in the College of Information Sciences and Technology at the University Park campus of The Pennsylvania State University have been practicing Red Team Analysis since 2008. RCA draws heavily from the military application of the same concept, except student RCA problems are typically on non-military in nature. RCA students utilize a suite of analytic tools and methods to explore and develop red-cell tactics, techniques and procedures (TTPs), and apply their tradecraft across a broad threat spectrum, from student-life issues to threats to national security. The strength of RCA is not always realized by the solution but by the exploration of the analytic pathway. This paper describes the concept and use of red cell analytics to teach and promote the use of structured analytic techniques, analytic writing and critical thinking in the area of security and risk and intelligence training.

  13. Monoclonal gammopathy-associated pure red cell aplasia.

    PubMed

    Korde, Neha; Zhang, Yong; Loeliger, Kelsey; Poon, Andrea; Simakova, Olga; Zingone, Adriana; Costello, Rene; Childs, Richard; Noel, Pierre; Silver, Samuel; Kwok, Mary; Mo, Clifton; Young, Neal; Landgren, Ola; Sloand, Elaine; Maric, Irina

    2016-06-01

    Pure red cell aplasia (PRCA) is a rare disorder characterized by inhibition of erythroid precursors in the bone marrow and normochromic, normocytic anaemia with reticulocytopenia. Among 51 PRCA patients, we identified 12 (24%) patients having monoclonal gammopathy, monoclonal gammopathy of undetermined significance or smouldering multiple myeloma, with presence of monoclonal protein or abnormal serum free light chains and atypical bone marrow features of clonal plasmacytosis, hypercellularity and fibrosis. Thus far, three patients treated with anti-myeloma based therapeutics have responded with reticulocyte recovery and clinical transfusion independence, suggesting plasma cells play a key role in the pathogenesis of this specific monoclonal gammopathy-associated PRCA. PMID:26999424

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

    NASA Astrophysics Data System (ADS)

    Carpenter, Cody Westcott

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

  15. Dealcoholated red wine induces autophagic and apoptotic cell death in an osteosarcoma cell line.

    PubMed

    Tedesco, I; Russo, M; Bilotto, S; Spagnuolo, C; Scognamiglio, A; Palumbo, R; Nappo, A; Iacomino, G; Moio, L; Russo, G L

    2013-10-01

    Until recently, the supposed preventive effects of red wine against cardiovascular diseases, the so-called "French Paradox", has been associated to its antioxidant properties. The interest in the anticancer capacity of polyphenols present in red wine strongly increased consequently to the enormous number of studies on resveratrol. In this study, using lyophilized red wine, we present evidence that its anticancer effect in a cellular model is mediated by apoptotic and autophagic cell death. Using a human osteosarcoma cell line, U2Os, we found that the lyophilized red wine was cytotoxic in a dose-dependent manner with a maximum effect in the range of 100-200 μg/ml equivalents of gallic acid. A mixed phenotype of types I/II cell death was evidenced by means of specific assays following treatment of U2Os with lyophilized red wine, e.g., autophagy and apoptosis. We found that cell death induced by lyophilized red wine proceeded through a mechanism independent from its anti-oxidant activity and involving the inhibition of PI3K/Akt kinase signaling. Considering the relative low concentration of each single bioactive compound in lyophilized red wine, our study suggests the activation of synergistic mechanism able to inhibit growth in malignant cells.

  16. Leukocyte transport by red blood cells in a microvessel

    NASA Astrophysics Data System (ADS)

    Freund, Jonathan

    2009-11-01

    A simulation model is used to study the transport of relatively large, spherical, and stiff white blood cells (leukocytes) by the relatively smaller and highly flexible red cell as they flow in the microcirculation. Their interaction dynamics are thought to be an important component of the inflammation response, in which leukocytes bind to the walls of blood vessels. The red cells are modeled in the simulations as highly deformable three-dimensional shells encasing a Newtonian fluid, and the viscous-flow equation is solved via a boundary integral formulation in which the cell shapes discretized by global spectral basis functions. For slow flow rates, it is found that the leukocyte is predominantly adjacent the vessel walls, whereas for faster flow rates this configuration appears to become unstable and the leukocyte traverses the whole vessel in a seemingly random fashion. For the straight round tubes simulated thus far, the stable leukocyte stand-off distance is always beyond the range of the binding molecules that capture it, which suggests that vessel inhomogeneities or interactions with other white cells are needed to create contact and thereby binding with the vessel walls.

  17. Flow of Red Blood Cells in Stenosed Microvessels

    PubMed Central

    Vahidkhah, Koohyar; Balogh, Peter; Bagchi, Prosenjit

    2016-01-01

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

  18. Flow of Red Blood Cells in Stenosed Microvessels

    NASA Astrophysics Data System (ADS)

    Vahidkhah, Koohyar; Balogh, Peter; Bagchi, Prosenjit

    2016-06-01

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

  19. Design Of A Hybrid Jet Impingement / Microchannel Cooling Device For Densely Packed PV Cells Under High Concentration

    NASA Astrophysics Data System (ADS)

    Barrau, Jérôme; Rosell, Joan; Ibañez, Manel

    2010-10-01

    A hybrid jet impingement / microchannel cooling scheme was designed and applied to densely packed PV cells under high concentration. An experimental study allows validating the principles of the design and confirming its applicability to the cited system. In order to study the characteristics of the device in a wide range of conditions, a numerical model was developed and experimentally validated. The results allow evaluating the contributions of the cooling device to the performances of densely packed PV cells under high concentration. The main advantages of the system are related to its compactness, its good capacity of heat extraction associated to relatively low pressure losses and its capability to improve the temperature uniformity of the PV receiver with respect to other cooling schemes. These features improve the net electric output of the whole system and its reliability.

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

    PubMed

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

    1996-01-01

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

  1. Blood clinical biochemistry and packed cell volume of the Chinese three-striped box turtle, Cuora trifasciata (Reptilia: Geoemydidae).

    PubMed

    Grioni, Alessandro; Ho, Kevin K Y; Karraker, Nancy E; Leung, Kenneth M Y

    2014-06-01

    Reference intervals for blood biochemical analytes and packed cell volume are useful to veterinarians and conservation programs for monitoring the health of threatened species. Populations of the critically endangered Chinese three-striped box turtle, Cuora trifasciata (Bell, 1825), are heavily depleted in the wild because of overharvesting; and many individuals are now maintained in captive breeding programs. Reference intervals of biochemical analytes and packed cell volume were established for individuals of this species held in a captive breeding program at Kadoorie Farm and Botanic Garden, Hong Kong. Blood samples were obtained from 86 healthy individuals from a captive population during annual health examinations between 2006 and 2010. Packed cell volume and 17 biochemical analytes were measured, and data were analyzed using both multivariate and univariate statistical analyses. Significant differences in eight analytes between males and females were identified. Ten analytes were found to increase or decrease significantly with the body weight of the turtles. The reported plasma reference intervals, based on 2.5th and 97.5th percentiles, may serve as benchmarks for clinical assessment and conservation of this critically endangered species. PMID:25000682

  2. Blood clinical biochemistry and packed cell volume of the Chinese three-striped box turtle, Cuora trifasciata (Reptilia: Geoemydidae).

    PubMed

    Grioni, Alessandro; Ho, Kevin K Y; Karraker, Nancy E; Leung, Kenneth M Y

    2014-06-01

    Reference intervals for blood biochemical analytes and packed cell volume are useful to veterinarians and conservation programs for monitoring the health of threatened species. Populations of the critically endangered Chinese three-striped box turtle, Cuora trifasciata (Bell, 1825), are heavily depleted in the wild because of overharvesting; and many individuals are now maintained in captive breeding programs. Reference intervals of biochemical analytes and packed cell volume were established for individuals of this species held in a captive breeding program at Kadoorie Farm and Botanic Garden, Hong Kong. Blood samples were obtained from 86 healthy individuals from a captive population during annual health examinations between 2006 and 2010. Packed cell volume and 17 biochemical analytes were measured, and data were analyzed using both multivariate and univariate statistical analyses. Significant differences in eight analytes between males and females were identified. Ten analytes were found to increase or decrease significantly with the body weight of the turtles. The reported plasma reference intervals, based on 2.5th and 97.5th percentiles, may serve as benchmarks for clinical assessment and conservation of this critically endangered species.

  3. 7 CFR 51.310 - Packing requirements.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... (INSPECTION, CERTIFICATION, AND STANDARDS) United States Standards for Grades of Apples Packing Requirements § 51.310 Packing requirements. (a) Apples tray packed or cell packed in cartons shall be arranged.... 3 2 “Fairly tight” means that apples are of the proper size for molds or cell compartments in...

  4. 7 CFR 51.310 - Packing requirements.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... (INSPECTION, CERTIFICATION, AND STANDARDS) United States Standards for Grades of Apples Packing Requirements § 51.310 Packing requirements. (a) Apples tray packed or cell packed in cartons shall be arranged.... 3 2 “Fairly tight” means that apples are of the proper size for molds or cell compartments in...

  5. Determination of Urea Permeability in Red Cells by Minimum Method

    PubMed Central

    Sha'afi, R. I.; Rich, G. T.; Mikulecky, D. C.; Solomon, A. K.

    1970-01-01

    A new method has been developed for measuring the permeability coefficient, ω, of small nonelectrolytes. The method depends upon a mathematical analysis of the time course of cell volume changes in the neighborhood of the minimum volume following addition of a permeating solute to an isosmolal buffer. Coefficients determined by the minimum volume method agree with those obtained using radioactive tracers. ω for urea in human red cells was found to decrease as the volume flow, Jv, into the cell increased. Such behavior is entirely unexpected for a single uniform rate-limiting barrier on the basis of the linear phenomenological equations derived from irreversible thermodynamics. However, the present findings are consonant with a complex membrane system consisting of a tight barrier on the outer face of the human red cell membrane and a somewhat less restrictive barrier behind it closer to the inner membrane face. A theoretical analysis of such a series model has been made which makes predictions consistent with the experimental findings. PMID:5435779

  6. Red cell glycolytic enzyme disorders caused by mutations: an update.

    PubMed

    Climent, Fernando; Roset, Feliu; Repiso, Ada; Pérez de la Ossa, Pablo

    2009-06-01

    Glycolysis is one of the principle pathways of ATP generation in cells and is present in all cell tissues; in erythrocytes, glycolysis is the only pathway for ATP synthesis since mature red cells lack the internal structures necessary to produce the energy vital for life. Red cell deficiencies have been detected in all erythrocyte glycolytic pathways, although their frequencies differ owing to diverse causes, such as the affected enzyme and severity of clinical manifestations. The number of enzyme deficiencies known is endless. The most frequent glycolysis abnormality is pyruvate kinase deficiency, since around 500 cases are known, the first of which was reported in 1961. However, only approximately 200 cases were due to mutations. In contrast, only one case of phosphoglycerate mutase BB type mutation, described in 2003, has been detected. Most mutations are located in the coding sequences of genes, while others, missense, deletions, insertions, splice defects, premature stop codons and promoter mutations, are also frequent. Understanding of the crystal structure of enzymes permits molecular modelling studies which, in turn, reveal how mutations can affect enzyme structure and function. PMID:19519368

  7. Deformation of red blood cells using acoustic radiation forces

    PubMed Central

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

    2014-01-01

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

  8. Nonequilibrium cell model for packed distillation columns -- The influence of maldistribution

    SciTech Connect

    Higler, A.; Krishna, R.; Taylor, R.

    1999-10-01

    In this paper the authors present a nonequilibrium model for studying the effects of flow maldistribution in packed columns. The model consists of a set of mass and energy balances along with a set of mass- and energy-transfer correlations. Maldistribution is treated by means of the zone/stage approach, as developed by Zuiderweg et al. Simulations show that, for binary mixtures, packing HETPs are a function of the height of the packing. It should be noted that in some cases the behavior of HETPs is not intuitive, even for binary mixtures. For ternary mixtures, cases were found in which differences in maldistribution patterns can result in substantial differences in column behavior; in some cases completely different column products can be obtained.

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

    PubMed

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

    2016-01-25

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

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

    PubMed

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

    2016-01-25

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

  11. Blood bank issues associated with red cell exchanges in sickle cell disease.

    PubMed

    Sarode, Ravindra; Altuntas, Fevzi

    2006-12-01

    Sickle cell disease (SCD) patients are prone to develop complications that include stroke, acute chest syndrome, and other crises. Some of these complications require chronic transfusion therapy or red cell exchange (RCE), either for therapeutic or prophylactic reasons. Due to a discrepancy of red cell antigens between African Americans and Caucasians (majority blood donors), the incidence of alloantibody formation is very high, which makes it difficult to find compatible red cell units, especially for urgent RCE. Some of the above conditions require immediate oxygen delivery to the tissues. Thus, SCD patients undergoing RCE should receive red blood cells with special attributes that include matching for Rh and Kell blood group antigens; RBCs should be fresh in order to provide (1) immediate oxygen delivery and (2) longer surviving cells to reduce the interval between RCE. Also, these units should be pre-storage leukoreduced to prevent febrile non-hemolytic reactions and screened for sickle cell traits to avoid transfusing red cells containing HbS. This requires a concerted effort between the apheresis unit, the local blood bank, and the central blood supplier. PMID:17177280

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

    SciTech Connect

    Parker, J.C.

    1984-11-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2015-06-01

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

  14. Transport of diseased red blood cells in the spleen

    NASA Astrophysics Data System (ADS)

    Peng, Zhangli; Pivkin, Igor; Dao, Ming

    2012-11-01

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

  15. Vibrational modes of hemoglobin in red blood cells.

    PubMed

    Martel, P; Calmettes, P; Hennion, B

    1991-02-01

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

  16. Relationships between oxidative stress markers and red blood cell characteristics in renal azotemic dogs.

    PubMed

    Buranakarl, C; Trisiriroj, M; Pondeenana, S; Tungjitpeanpong, T; Jarutakanon, P; Penchome, R

    2009-04-01

    Oxidative stress parameters and erythrocyte characteristics were studied in 15 normal healthy dogs and 33 renal azotaemic dogs from Small Animal Hospital, Faculty of Veterinary Science, Chulalongkorn University. Dogs with renal azotaemia had reduced mean corpuscular volume (MCV) (P<0.01), packed cell volume (PCV) (P<0.001) and increased mean corpuscular hemoglobin concentration (MCHC) (P<0.001). The relationship was found between degree of azotaemia and MCV, PCV and MCHC. Dogs with severe renal azotaemia had higher intraerythrocytic sodium contents (RBC-Na) (P<0.05). The red blood cell catalase activity and glutathione and plasma malondialdehyde were unaltered while urinary malondialdehyde-creatinine ratio (U-MDA/Cr) increased significantly (P<0.001). The U-MDA/Cr was correlated significantly with plasma creatinine concentration (P<0.05), urinary protein-creatinine ratio (P<0.05) and fractional excretion of sodium (P<0.001). The results suggest some changes in RBC characteristics and urine oxidative stress marker in renal azotaemic dogs. Moreover, the U-MDA/Cr is a sensitive biochemical parameter which increased along with degree of renal dysfunction.

  17. The nature of multiphoton fluorescence from red blood cells

    NASA Astrophysics Data System (ADS)

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

    2016-03-01

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

  18. Admission red cell distribution width: a novel predictor of massive transfusion after injury.

    PubMed

    Paulus, Elena M; Weinberg, Jordan A; Magnotti, Louis J; Sharpe, John P; Schroeppel, Thomas J; Fabian, Timothy C; Croce, Martin A

    2014-07-01

    Admission red cell distribution width (aRDW) has been shown to predict mortality in trauma patients by an unclear mechanism. It has been speculated that aRDW is a marker of chronic health status, but elevated RDW may also reflect recent hemorrhage. We hypothesized that aRDW is a predictor of major hemorrhage in trauma patients. Shock trauma patients at a Level I trauma center over 6.5 years were evaluated. Patients were stratified by aRDW quintile (Q1: less than 13%, Q2: 13.1 to 13.5%, Q3: 13.6 to 14.0%, Q4: 14.1 to 14.9%, Q5: 15.0% or greater). Massive transfusion (MT) was defined as 10 or more packed red blood cells in the first 24 hours. From multiple logistic regression, odds ratios with 95 per cent confidence intervals (CIs) were determined to evaluate the association between aRDW quintile and MT. Three thousand nine hundred ninety-four met study criteria. Overall MT incidence was 10 per cent and in-hospital mortality was 17 per cent. MT and mortality increased in a stepwise fashion by aRDW quintile (P < 0.0001). From logistic regression, a threefold increased odds of MT was associated with aRDW Q4 (CI, 1.81 to 4.92), and a 3.5-fold increased odds of MT was associated with aRDW Q5 (CI, 2.70 to 5.83). aRDW independently predicted MT, suggesting that elevated aRDW is an indicator of major hemorrhage in trauma patients. The association between aRDW and mortality in trauma patients may be explained by acute hemorrhage rather than chronic health status.

  19. Sodium-dependent magnesium uptake by ferret red cells.

    PubMed Central

    Flatman, P W; Smith, L M

    1991-01-01

    1. Magnesium uptake can be measured in ferret red cells incubated in media containing more than 1 mM-magnesium. Uptake is substantially increased if the sodium concentration in the medium is reduced. 2. Magnesium uptake is half-maximally activated by 0.37 mM-external magnesium when the external sodium concentration is 5 mM. Increasing the external sodium concentration increases the magnesium concentration needed to activate the system. 3. Magnesium uptake is increased by reducing the external sodium concentration. Uptake is half-maximum at sodium concentrations of 17, 22 and 62 nM when the external magnesium concentrations are 2, 5 and 10 mM respectively. 4. Replacement of external sodium with choline does not affect the membrane potential of ferret red cells over a 45 min period. 5. Magnesium uptake from media containing 5 mM-sodium is inhibited by amiloride, quinidine and imipramine. It is not affected by ouabain or bumetanide. Vanadate stimulates magnesium uptake but has no effect on magnesium efflux. 6. When cell ATP content is reduced to 19 mumol (1 cell)-1 by incubating cells for 3 h with 2-deoxyglucose, magnesium uptake falls by 50% in the presence of 5 mM-sodium and is completely abolished in the presence of 145 mM-sodium. Some of the inhibition may be due to the increase in intracellular ionized magnesium concentration ([Mg2+]i) from 0.7 to 1.0 mM which occurs under these conditions. 7. Magnesium uptake can be driven against a substantial electrochemical gradient if the external sodium concentration is reduced sufficiently. 8. These findings are discussed in terms of several possible models for magnesium transport. It is concluded that the majority of magnesium uptake observed in low-sodium media is via sodium-magnesium antiport. A small portion of uptake is through a parallel leak pathway. It is believed that the antiport is responsible for maintaining [Mg2+]i below electrochemical equilibrium in these cells at physiological external sodium concentration

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

    PubMed

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

    2015-02-01

    Cryopreserved (frozen) red blood cells have been used in transfusion medicine since the Vietnam war. The main method to freeze the red blood cells is by usage of glycerol. Although the usage of cryopreserved red blood cells was promising due to the prolonged storage time and the limited cellular deterioration at subzero temperatures, its usage have been hampered due to the more complex and labour intensive procedure and the limited shelf life of thawed products. Since the FDA approval of a closed (de) glycerolization procedure in 2002, allowing a prolonged postthaw storage of red blood cells up to 21 days at 2-6°C, cryopreserved red blood cells have become a more utilized blood product. Currently, cryopreserved red blood cells are mainly used in military operations and to stock red blood cells with rare phenotypes. Yet, cryopreserved red blood cells could also be useful to replenish temporary blood shortages, to prolong storage time before autologous transfusion and for IgA-deficient patients. This review describes the main methods to cryopreserve red blood cells, explores the quality of this blood product and highlights clinical settings in which cryopreserved red blood cells are or could be utilized. PMID:25471135

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

    PubMed

    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 < .05). The PTV decreased from 94% using day 1 red blood cells to 80% and 75% using day 37 and day 44 red blood cells, respectively (P < .05). Although the mean PTV of the day 44 stored units equaled the 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.

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

    PubMed Central

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

    2014-01-01

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

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

    NASA Astrophysics Data System (ADS)

    Bagchi, Prosenjit; Cordasco, Daniel

    2015-11-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2012-11-01

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

  5. From stem cell to erythroblast: regulation of red cell production at multiple levels by multiple hormones.

    PubMed

    Lodish, Harvey; Flygare, Johan; Chou, Song

    2010-07-01

    This article reviews the regulation of production of red blood cells at several levels: (1) the ability of erythropoietin and adhesion to a fibronectin matrix to stimulate the rapid production of red cells by inducing terminal proliferation and differentiation of committed erythroid CFU-E progenitors; (2) the regulated expansion of the pool of earlier BFU-E erythroid progenitors by glucocorticoids and other factors that occurs during chronic anemia or inflammation; and (3) the expansion of thehematopoietic cell pool to produce more progenitors of all hematopoietic lineages.

  6. Red blood cell extrudes nucleus and mitochondria against oxidative stress.

    PubMed

    Zhang, Zhong-Wei; Cheng, Jian; Xu, Fei; Chen, Yang-Er; Du, Jun-Bo; Yuan, Ming; Zhu, Feng; Xu, Xiao-Chao; Yuan, Shu

    2011-07-01

    Mammal red blood cells (erythrocytes) contain neither nucleus nor mitochondria. Traditional theory suggests that the presence of a nucleus would prevent big nucleated erythrocytes to squeeze through these small capillaries. However, nucleus is too small to hinder erythrocyte deformation. And, there is no sound reason to abandon mitochondria for the living cells. Here, we found that mammal erythrocyte reactive oxygen species (ROS) levels kept stable under diabetes, ischemia reperfusion, and malaria conditions or in vitro sugar/heme treatments, whereas bird erythrocyte ROS levels increased dramatically in these circumstances. Nuclear and mitochondrial extrusion may help mammal erythrocytes to better adapt to high-sugar and high-heme conditions by limiting ROS generation. PMID:21698761

  7. Anisotropic light scattering of individual sickle red blood cells

    NASA Astrophysics Data System (ADS)

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

    2012-04-01

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

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

    NASA Astrophysics Data System (ADS)

    Zhu, Qiang; Peng, Zhangli

    2012-11-01

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

  9. Perchlorate remediation using packed-bed bioreactors and electricity generation in microbial fuel cells (MFCs)

    NASA Astrophysics Data System (ADS)

    Min, Booki

    Two pilot-scale fixed bed bioreactors were operated in continuous mode in order to treat groundwater contaminated by perchlorate. The bioreactors were constructed and operated side-by-side at the Texas Street Well Facility in Redlands, California. Each reactor was packed with either sand or plastic media. A perchlorate-reducing bacterium, Dechlorosoma sp. KJ, was used to inoculate the bioreactors. Perchlorate was successfully removed down to a non-detectable level (<4mug/L) in both bioreactors with acetate as a carbon source and nutrients at loading rates less than 0.063 L/s (1 gpm; 0.34 L/m2s). The sand medium bioreactor could achieve complete-perchlorate removal up to flow rate of 0.126 L/s. A regular backwashing cycle (once a week) was an important factor for completely removing perchlorate in groundwater. Power generation directly from pure or mixed organic matter was examined using microbial fuel cells (MFCs), which were run either in batch or continuous mode. In batch experiments, both a pure culture (Geobactor metallireducens) and a mixed culture (wastewater inoculum) were used as the biocatalyst, and acetate was added as substrate in the anode chamber of the MFC. Power output in a membrane MFC with either inoculum was essentially the same, with 40 +/- 1 mW/m2 for G. metallireducens and 38 +/- 1 mW/m2 for mixed culture. A different type of the MFC containing a salt bridge instead of a membrane system was examined to generate power using the same substrate and pure culture as used in the membrane MFC. Power output in the salt bridge MFC was 2.2 mW/m 2. It was found that the lower power output was directly attributed to the higher internal resistance of the salt bridge system (19920 +/- 50 O) in comparison with that of the membrane system (1286 +/- 1 O). Continuous electricity generation was examined in a flat plate microbial fuel cell (FPMFC) using domestic wastewater and specific organic substrates. The FPMFC, containing a combined electrode/proton exchange

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

    SciTech Connect

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

    2012-06-30

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

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

    SciTech Connect

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

    2014-08-31

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

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

    NASA Technical Reports Server (NTRS)

    Talbot, J. M.; Fisher, K. D.

    1985-01-01

    Decreases of red blood cell mass and plasma volume have been observed consistently following manned space flights. Losses of red cell mass by United States astronauts have averaged 10 to 15% (range: 2 to 21%). Based on postflight estimates of total hemoglobin, Soviet cosmonauts engaged in space missions lasting from 1 to 7 months have exhibited somewhat greater losses. Restoration of red cell mass requires from 4 to 6 weeks following return to Earth, regardless of the duration of space flight.

  13. Lipid peroxidation affects red blood cells membrane properties in patients with systemic lupus erythematosus.

    PubMed

    Spengler, M I; Svetaz, M J; Leroux, M B; Bertoluzzo, S M; Parente, F M; Bosch, P

    2014-01-01

    Systemic lupus erythematosus (SLE) is an autoimmune, chronic inflammatory, non-organ specific disease with an important morbimortality affecting several organs and systems. Oxidative stress is a well documented mechanism of red blood cells (RBC) mechanical impairment. Free radicals could produced, through lipid peroxidation, physical and chemical alterations in the cellular membrane properties modifying its composition, packing and lipid distribution on the membrane erythrocyte. The aim of the present work is to study the lipid peroxidation in the RBC membrane in SLE patients (n = 42) affecting so far the lipid membrane fluidity and erythrocyte deformability in comparison with healthy controls (n = 52). Malonildialdehyde (MDA) is a subrogate assessing lipidic peroxidation, rigidity index estimating erythrocyte deformability and the anisotropy coefficient estimating lipid membrane fluidity were used. Our results show that MDA values are increased, while erythrocyte deformability and membrane fluidity are significantly decreased in erythrocyte membrane from SLE patients in comparison with normal controls. The association of thiobarbituric acid reactive substances (TBARS) with membrane lipid fluidity and erythrocyte deformability confirms that the damage of membrane properties is produced by lipid peroxidation. PMID:23603321

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

    SciTech Connect

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

    1991-03-01

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

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

    PubMed Central

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

    2016-01-01

    In sickle cell disease (SCD), hemoglobin molecules polymerize intracellularly and lead to a cascade of events resulting in decreased deformability and increased adhesion of red blood cells (RBCs). Decreased deformability and increased adhesion of sickle RBCs lead to blood vessel occlusion (vaso-occlusion) in SCD patients. Here, we present a microfluidic approach integrated with a cell dimensioning algorithm to analyze dynamic deformability of adhered RBC at the single-cell level in controlled microphysiological flow. We measured and compared dynamic deformability and adhesion of healthy hemoglobin A (HbA) and homozygous sickle hemoglobin (HbS) containing RBCs in blood samples obtained from 24 subjects. We introduce a new parameter to assess deformability of RBCs: the dynamic deformability index (DDI), which is defined as the time-dependent change of the cell’s aspect ratio in response to fluid flow shear stress. Our results show that DDI of HbS-containing RBCs were significantly lower compared to that of HbA-containing RBCs. Moreover, we observed subpopulations of HbS containing RBCs in terms of their dynamic deformability characteristics: deformable and non-deformable RBCs. Then, we tested blood samples from SCD patients and analyzed RBC adhesion and deformability at physiological and above physiological flow shear stresses. We observed significantly greater number of adhered non-deformable sickle RBCs than deformable sickle RBCs at flow shear stresses well above the physiological range, suggesting an interplay between dynamic deformability and increased adhesion of RBCs in vaso-occlusive events. PMID:27437432

  16. Modeling of Red Blood Cells and Related Spleen Function

    NASA Astrophysics Data System (ADS)

    Peng, Zhangli; Pivkin, Igor; Dao, Ming

    2011-11-01

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

  17. P2X and P2Y receptor signaling in red blood cells

    PubMed Central

    Sluyter, Ronald

    2015-01-01

    Purinergic signaling involves the activation of cell surface P1 and P2 receptors by extracellular nucleosides and nucleotides such as adenosine and adenosine triphosphate (ATP), respectively. P2 receptors comprise P2X and P2Y receptors, and have well-established roles in leukocyte and platelet biology. Emerging evidence indicates important roles for these receptors in red blood cells. P2 receptor activation stimulates a number of signaling pathways in progenitor red blood cells resulting in microparticle release, reactive oxygen species formation, and apoptosis. Likewise, activation of P2 receptors in mature red blood cells stimulates signaling pathways mediating volume regulation, eicosanoid release, phosphatidylserine exposure, hemolysis, impaired ATP release, and susceptibility or resistance to infection. This review summarizes the distribution of P2 receptors in red blood cells, and outlines the functions of P2 receptor signaling in these cells and its implications in red blood cell biology. PMID:26579528

  18. Concise Review: Production of Cultured Red Blood Cells from Stem Cells

    PubMed Central

    2012-01-01

    In the Western world, the volunteer-based collection system covers most transfusion needs, but transient shortages regularly develop and blood supplies are vulnerable to potentially major disruptions. The production of cultured red blood cells from stem cells is slowly emerging as a potential alternative. The various cell sources, the niche applications most likely to reach the clinic first, and some of the remaining technical issues are reviewed here. PMID:23283554

  19. Comparative study of cytotoxic and genotoxic effects induced by herbicide S-metolachlor and its commercial formulation Twin Pack Gold® in human hepatoma (HepG2) cells.

    PubMed

    Nikoloff, Noelia; Escobar, Luciana; Soloneski, Sonia; Larramendy, Marcelo L

    2013-12-01

    The in vitro effects of S-metolachlor and its formulation Twin Pack Gold(®) (96% a.i.) were evaluated in human hepatoma (HepG2) cells. Cytokinesis-blocked micronucleus cytome (CBMN-cyt) and MTT assays as well as Neutral Red uptake were employed for genotoxicity and cytotoxicity evaluation. Activities were tested within the concentration range of 0.25-15 μg/ml S-metolachlor for 24h of exposure. Both compounds rendered a minor reduction in the NDI although not reaching statistical significance. Results demonstrated that the S-metolachlor was not able to induce MNs. On the other hand, 0.5-6 μg/ml Twin Pack Gold(®) increased the frequency of MNs. When cytotoxicity was estimated, S-metolachlor was not able to induce either a reduction of lysosomal or mitochondrial activity. Contrarily, whereas 1-15 μg/ml Twin Pack Gold(®) induced a significant reduction of mitochondrial activity, all tested concentrations of the formulated product induced a significant decrease of lysosomal performance as a function of the concentration of the S-metolachlor-based formulation titrated into cultures. Genotoxicity and cytotoxicity differences obtained with pure S-metolachlor and the commercial S-metolachlor-based formulation indicate that the latter may contain additional unsafe xenobiotics and support the concept of the importance of evaluating not only the active principle but also the commercial formulation when estimating the real hazard from agrochemicals.

  20. Acquired pure red cell aplasia: updated review of treatment

    PubMed Central

    Sawada, Kenichi; Fujishima, Naohito; Hirokawa, Makoto

    2008-01-01

    Pure red cell aplasia (PRCA) is a syndrome characterized by a severe normocytic anaemia, reticulocytopenia, and absence of erythroblasts from an otherwise normal bone marrow. Primary PRCA, or secondary PRCA which has not responded to treatment of the underlying disease, is treated as an immunologically-mediated disease. Although vigorous immunosuppressive treatments induce and maintain remissions in a majority of patients, they carry an increased risk of serious complications. Corticosteroids were used in the treatment of PRCA and this has been considered the treatment of first choice although relapse is not uncommon. Cyclosporine A (CsA) has become established as one of the leading drugs for treatment of PRCA. However, common concerns have been the number of patients treated with CsA who achieve sustained remissions and the number that relapse. This article reviews the current status of CsA therapy and compares it to other treatments for diverse PRCAs. PMID:18510682

  1. Plasma and red blood cell fatty acids in peroxisomal disorders.

    PubMed

    Moser, A B; Jones, D S; Raymond, G V; Moser, H W

    1999-02-01

    The demonstration of abnormal levels of fatty acids or plasmalogens in plasma or red blood cells is key to the diagnosis of peroxisomal disorders. We report the levels of 62 fatty acids and plasmalogens in patients with X-linked adrenoleukodystrophy (X-ALD), Zellweger syndrome (ZS), neonatal adrenoleukodystrophy (NALD), and infantile Refsum disease (IRD), both at baseline and after dietary interventions. "Lorenzo's Oil" therapy in X-ALD normalizes the levels of saturated very long chain fatty acids in plasma, but leads to reduced levels of omega 6 and other omega 3 fatty acids, and requires monitoring and appropriate dietary supplements. Patients with ZS, NALD and IRD have reduced levels of docosahexaenoic acid (DHA) and arachidonic acid (AA) which can be normalized by the oral administration of microencapsulated DHA and AA.

  2. Pure red cell aplasia following autoimmune hemolytic anemia: an enigma.

    PubMed

    Saha, M; Ray, S; Kundu, S; Chakrabarti, P

    2013-01-01

    A 26-year-old previously healthy female presented with a 6-month history of anemia. The laboratory findings revealed hemolytic anemia and direct antiglobulin test was positive. With a diagnosis of autoimmune hemolytic anemia (AIHA), prednisolone was started but was ineffective after 1 month of therapy. A bone marrow trephine biopsy revealed pure red cell aplasia (PRCA) showing severe erythroid hypoplasia. The case was considered PRCA following AIHA. This combination without clear underlying disease is rare. Human parvovirus B19 infection was not detected in the marrow aspirate during reticulocytopenia. The patient received azathioprine, and PRCA improved but significant hemolysis was once again documented with a high reticulocyte count. The short time interval between AIHA and PRCA phase suggested an increased possibility of the evolution of a single disease.

  3. Autoimmune Hemolytic Anemia and Red Blood Cell Autoantibodies.

    PubMed

    Quist, Erin; Koepsell, Scott

    2015-11-01

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

  4. Mobility Enhancement of Red Blood Cells with Biopolymers

    NASA Astrophysics Data System (ADS)

    Tahara, Daiki; Oikawa, Noriko; Kurita, Rei

    2016-03-01

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

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

    PubMed

    Hortolà, P

    1992-08-01

    Mammal red blood cells (RBC) in bloodstains have been previously detected by light microscopy on stone tools from as early as 100,000 +/- 25,000 years ago. In order to evaluate the degree of morphological preservation of erythrocytes in bloodstains, an accidental human blood smear on white chert and several experimental bloodstains on hard substrates (the same stone-white chert; another type of stone-graywacke; a non-stone support-stainless steel), were stored in a room, in non-sterile and fluctuating conditions, for lengths of time ranging from 3 to 18 months. Afterwards, the specimens were coated with gold and examined by a Cambridge Stereoscan 120 scanning electron microscope. Results revealed a high preservation of RBC integrity, with the maintenance of several discocytary shapes, a low tendency to echinocytosis and a frequent appearance of a moon-like erythrocytary shape in the thinner areas of the bloodstains. PMID:1398371

  6. Magnetic nanoparticle effects on the red blood cells

    NASA Astrophysics Data System (ADS)

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

    2009-05-01

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

  7. Anemia and red blood cell transfusion in neurocritical care

    PubMed Central

    Kramer, Andreas H; Zygun, David A

    2009-01-01

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

  8. Pure red cell aplasia secondary to treatment with erythropoietin.

    PubMed

    Locatelli, Francesco; Del Vecchio, Lucia

    2003-01-01

    Pure red cell aplasia (PRCA) is a rare condition defined as severe anemia secondary to the virtual absence of red blood cell precursors in the bone marrow. In the setting of patients treated with rHuEPO, the disease is generated by epoetin-induced antibodies that neutralise all the exogenous rHuEPO and cross-react with endogenous erythropoietin. As a result, serum erythropoietin levels are undetectable and erythropoiesis becomes ineffective. Only 4 cases of PRCA associated with rh-EPO have been reported before 1998. Thereafter, a sharp increase in the incidence of this rare condition has been reported, mainly associated with epoetin alpha use outside the United States. A number of possible mechanisms leading to PRCA development have been identified. Among these, modification of drug formulation and down stream processing probably has had a major role. Indeed, in 1998 the formulation of epoetin alpha in Europe was modified because of the fear of the "mad cow" syndrome. However, differences in molecule structure and glycosylation among different epoetins can not be excluded. It should also be underlined that the rise in the incidence of PRCA cases has been coincident with a major shift from intravenous to subcutaneous administration of rHuEPO. The abrupt rise in the incidence of PRCA cases observed in the last few years, deserves particular attention; however, we have to balance its severity, but extreme rarity, with the high number of chronic kidney disease patients who die each year because of cardiovascular disease that could partially be reduced by anemia treatment. PMID:14696747

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

    PubMed

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

    2016-08-16

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

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

    PubMed

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

    2016-08-16

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

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

    PubMed Central

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

    2014-01-01

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

  12. Depletion-mediated red blood cell aggregation in polymer solutions.

    PubMed

    Neu, Björn; Meiselman, Herbert J

    2002-11-01

    Polymer-induced red blood cell (RBC) aggregation is of current basic science and clinical interest, and a depletion-mediated model for this phenomenon has been suggested; to date, however, analytical approaches to this model are lacking. An approach is thus described for calculating the interaction energy between RBC in polymer solutions. The model combines electrostatic repulsion due to RBC surface charge with osmotic attractive forces due to polymer depletion near the RBC surface. The effects of polymer concentration and polymer physicochemical properties on depletion layer thickness and on polymer penetration into the RBC glycocalyx are considered for 40 to 500 kDa dextran and for 18 to 35 kDa poly (ethylene glycol). The calculated results are in excellent agreement with literature data for cell-cell affinities and with RBC aggregation-polymer concentration relations. These findings thus lend strong support to depletion interactions as the basis for polymer-induced RBC aggregation and suggest the usefulness of this approach for exploring interactions between macromolecules and the RBC glycocalyx. PMID:12414682

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

    PubMed Central

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

    2013-01-01

    Macrophages tightly control the production and clearance of red blood cells (RBC). During steady state hematopoiesis, approximately 1010 RBC are produced per hour within erythroblastic islands in humans. In these erythroblastic islands, resident bone marrow macrophages provide erythroblasts with interactions that are essential for erythroid development. New evidence suggests that not only under homeostasis but also under stress conditions, macrophages play an important role in promoting erythropoiesis. Once RBC have matured, these cells remain in circulation for about 120 days. At the end of their life span, RBC are cleared by macrophages residing in the spleen and the liver. Current theories about the removal of senescent RBC and the essential role of macrophages will be discussed as well as the role of macrophages in facilitating the removal of damaged cellular content from the RBC. In this review we will provide an overview on the role of macrophages in the regulation of RBC production, maintenance and clearance. In addition, we will discuss the interactions between these two cell types during transfer of immune complexes and pathogens from RBC to macrophages. PMID:24523696

  14. Manipulation of red blood cells with electric field

    NASA Astrophysics Data System (ADS)

    Saboonchi, Hossain; Esmaeeli, Asghar

    2009-11-01

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

  15. A semi-mechanistic red blood cell survival model provides some insight into red blood cell destruction mechanisms.

    PubMed

    Korell, Julia; Duffull, Stephen B

    2013-08-01

    Most mathematical models developed for the survival of haematological cell populations, in particular red blood cells (RBCs), follow the principle of parsimony. They focus on the predominant destruction mechanism of age-related cell death (senescence) and do not account for within subject variability in the RBC lifespan. However, assessment of the underlying physiological destruction mechanisms can be of interest in pathological conditions that affect RBC survival, for example sickle cell anaemia or anaemia of chronic kidney disease. We have previously proposed a semi-mechanistic RBC survival model which accounts for four different types of RBC destruction mechanisms. In this work, it is shown that the proposed model in combination with informative RBC survival data is able to provide a deeper insight into RBC destruction mechanisms. The proposed model was applied in a non-linear mixed effect modelling framework to biotin derived RBC survival data available from literature. Three mechanisms were estimable based on the available data of twelve subjects, including random destruction, senescence and destruction due to delayed failure. It was possible to identify three subjects with a decreased RBC survival in the study population. These three subjects all showed differences in the contribution of the estimated destruction mechanisms: an increased random destruction, versus an accelerated senescence, versus a combination of both.

  16. Trypanosomiasis in Venezuelan water buffaloes: association of packed-cell volumes with seroprevalence and current trypanosome infection.

    PubMed

    García, H; García, M-E; Pérez, G; Bethencourt, A; Zerpa, E; Pérez, H; Mendoza-León, A

    2006-06-01

    The seroprevalence of trypanosomiasis and the prevalence of current trypanosome infection in water buffaloes from the most important livestock areas of Venezuela were evaluated by IFAT and the microhaematocrit centrifugation technique, respectively. The usefulness of a PCR-based assay for identifying the trypanosome species in the buffaloes was also evaluated. Of the 644 animals investigated, 40 (6.2%) were found infected with trypanosomes by blood centrifugation, and 196 (30.4%) were found positive for anti-trypanosome antibodies, by IFAT. The results of the PCR-based assay indicated that 92.5% of the animals with current infections were infected with Trypanosoma vivax and the rest with T. theileri (the first molecular confirmation of T. theileri in Venezuelan water buffaloes). The national programme to treat and prevent trypanosome infections in the buffaloes does not appear to be meeting with great success, even though it is focused on T. vivax. Although the level of parasitaemia was categorized as low for 28 (70%) of the infections detected (and packed-cell volumes appeared to be unassociated with IFAT result, and uncorrelated, in the infected animals, with level of parasitaemia), the 40 infected buffaloes had a significantly lower mean packed-cell volume than the uninfected animals (P<0.05). Farmers should therefore be made aware of the probability of trypanosome-attributable losses in buffalo productivity.

  17. Interaction forces between red cells agglutinated by antibody. III. Micromanipulation.

    PubMed Central

    Tha, S P; Goldsmith, H L

    1988-01-01

    In the flow studies described in two previous papers (Tha, S. P., and H. L. Goldsmith, 1986, Biophys. J. 50:1109-1116; Tha, S. P., J. Shuster, and H. L. Goldsmith, 1986, Biophys. J. 50:1117-1126), hydrodynamic forces of the order of 10(-11) N (mu dyn) were applied to measure the force of separation of doublets of hardened, sphered human red blood cells cross-linked by anti-B antibody. The same cell preparation and hyperimmune antiserum has here been used to carry out experiments with micropipet aspiration techniques. One cell of a doublet was aspirated onto a holding pipet, and a second aspiration pipet was brought into proximity of the other cell so that the two pipets and the doublet were colinear. Suction was then raised until the two cells separated. Some doublets were assembled by aspiration of a singlet, bringing a second singlet into apposition with the first, and releasing it from the pipet which was then withdrawn. Cells could be repeatedly assembled and separated. At 3.56% vol/vol antiserum, the mean normal force of separation was 0.45 +/- 0.11 nN in phosphate-buffered saline suspensions containing 2.5 x 10(4) cells/microliter; at 1.22% vol/vol antiserum, the value was 0.22 +/- 0.11 nN. The above values of the force were approximately 2.5 x greater than those from the flow studies. The data could be fitted to a Poisson distribution with 0.05 nN as the force needed to break a single cross-bridge (c.f. 0.024 nN from the previous hydrodynamic data). The forces of separation of randomly assembled doublets were lower than those of preexisting doublets. Repeated assembly and separation of doublets showed that the cell surfaces are nonuniform in adhesion strength both over the local scale less than 0.25 micron2 and the cell population. Images FIGURE 2 PMID:3134058

  18. Unbalanced discharging and aging due to temperature differences among the cells in a lithium-ion battery pack with parallel combination

    NASA Astrophysics Data System (ADS)

    Yang, Naixing; Zhang, Xiongwen; Shang, BinBin; Li, Guojun

    2016-02-01

    This paper presents an investigation on the unbalanced discharging and aging due to temperature difference between the parallel-connected cells. A thermal-electrochemical model is developed for the parallel-connected battery pack. The effects of temperature difference on the unbalanced discharging performances are studied by simulations and experiments. For the parallel-connected cells, the cell at higher temperature experiences a larger current in the early discharging process before approximately 75% of depth of discharge (DOD). When the discharge process approaches the voltage turn point of the battery pack, the discharge current through the cell at higher temperature begins to decrease significantly. After the DOD reaches approximately 90%, the discharge current of the cell at higher temperature rises again. Correspondingly, the changes in the discharging current through the cell at lower temperature are opposite to that of the cell at higher temperature. Simulations also show that the temperature difference between the parallel-connected cells greatly aggravates the imbalance discharge phenomenon between the cells, which accelerates the losses of the battery pack capacity. For the parallel-connected battery pack, the capacity loss rate approximately increases linearly as the temperature difference between the cells increases. This trend is magnified with the increase of operating temperature.

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

    DOEpatents

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

    1992-05-26

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

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

    DOEpatents

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

    1992-01-01

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

  1. Hydrogen ion dynamics in human red blood cells.

    PubMed

    Swietach, Pawel; Tiffert, Teresa; Mauritz, Jakob M A; Seear, Rachel; Esposito, Alessandro; Kaminski, Clemens F; Lew, Virgilio L; Vaughan-Jones, Richard D

    2010-12-15

    Our understanding of pH regulation within red blood cells (RBCs) has been inferred mainly from indirect experiments rather than from in situ measurements of intracellular pH (pH(i)). The present work shows that carboxy-SNARF-1, a pH fluorophore, when used with confocal imaging or flow cytometry, reliably reports pH(i) in individual, human RBCs, provided intracellular fluorescence is calibrated using a 'null-point' procedure. Mean pH(i) was 7.25 in CO(2)/HCO(3)(-)-buffered medium and 7.15 in Hepes-buffered medium, and varied linearly with extracellular pH (slope of 0.77). Intrinsic (non-CO(2)/HCO(3)(-)-dependent) buffering power, estimated in the intact cell (85 mmol (l cell)(-1) (pH unit)(-1) at resting pH(i)), was somewhat higher than previous estimates from cell lysates (50-70 mmol (l cell)(-1) (pH unit)(-1)). Acute displacement of pH(i) (superfusion of weak acids/bases) triggered rapid pH(i) recovery. This was mediated via membrane Cl(-)/HCO(3)(-) exchange (the AE1 gene product), irrespective of whether recovery was from an intracellular acid or base load, and with no evident contribution from other transporters such as Na(+)/H(+) exchange. H(+)-equivalent flux through AE1 was a linear function of [H(+)](i) and reversed at resting pH(i), indicating that its activity is not allosterically regulated by pH(i), in contrast to other AE isoforms. By simultaneously monitoring pH(i) and markers of cell volume, a functional link between membrane ion transport, volume and pH(i) was demonstrated. RBC pH(i) is therefore tightly regulated via AE1 activity, but modulated during changes of cell volume. A comparable volume-pH(i) link may also be important in other cell types expressing anion exchangers. Direct measurement of pH(i) should be useful in future investigations of RBC physiology and pathology. PMID:20962000

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

    NASA Astrophysics Data System (ADS)

    Shwetha, M.; Narayan, K.

    2016-03-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2005-08-01

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

  4. Mechanical response of red blood cells entering a constriction

    PubMed Central

    Zeng, Nancy F.; Ristenpart, William D.

    2014-01-01

    Most work on the dynamic response of red blood cells (RBCs) to hydrodynamic stress has focused on linear velocity profiles. Relatively little experimental work has examined how individual RBCs respond to pressure driven flow in more complex geometries, such as the flow at the entrance of a capillary. Here, we establish the mechanical behaviors of healthy RBCs undergoing a sudden increase in shear stress at the entrance of a narrow constriction. We pumped RBCs through a constriction in a microfluidic device and used high speed video to visualize and track the flow behavior of more than 4400 RBCs. We show that approximately 85% of RBCs undergo one of four distinct modes of motion: stretching, twisting, tumbling, or rolling. Intriguingly, a plurality of cells (∼30%) exhibited twisting (rotation around the major axis parallel to the flow direction), a mechanical behavior that is not typically observed in linear velocity profiles. We present detailed statistical analyses on the dynamics of each motion and demonstrate that the behavior is highly sensitive to the location of the RBC within the channel. We further demonstrate that the observed tumbling, twisting, and rolling rotations can be rationalized qualitatively in terms of rigid body mechanics. The detailed experimental statistics presented here should serve as a useful resource for modeling of RBC behavior under physiologically important flow conditions. PMID:25553197

  5. Piezo1 links mechanical forces to red blood cell volume

    PubMed Central

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

    2015-01-01

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

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

    PubMed

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

    2015-01-01

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

  7. Twisting of Red Blood Cells Entering a Constriction

    NASA Astrophysics Data System (ADS)

    Zeng, Nancy; Ristenpart, William

    2014-11-01

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

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

    NASA Technical Reports Server (NTRS)

    1976-01-01

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

  9. [In vitro generation of blood red cells from stem cells: a sketch of the future].

    PubMed

    Mazurier, Christelle; Douay, Luc

    2016-01-01

    Human adult pluripotent stem cells, stem cells of embryonic origin and induced pluripotent stem cells (iPS) provide cellular sources for new promising regenerative medicine approaches. Because these cells can be patient-specific, they allow considering a personalized medicine appropriate to the diagnosis of each. The generation of cultured red blood cells (cRBC) derived from stem cells is emblematic of personalized medicine. Indeed, these cells have the advantage of being selected according to a blood phenotype of interest and they may provide treatments to patients in situation of impossible transfusion (alloimmunized patients, rare phenotypes). Essential progresses have established proof of concept for this approach, still a concept some years ago. From adult stem cells, all steps of upstream research were successfully achieved, including the demonstration of the feasibility of injection into human. This leads us to believe that Red Blood Cells generated in vitro from stem cells will be the future players of blood transfusion. However, although theoretically ideal, these stem cells raise many biological challenges to overcome, although some tracks are identified. PMID:27286576

  10. Open Gradient Magnetic Red Blood Cell Sorter Evaluation on Model Cell Mixtures

    PubMed Central

    Moore, Lee R.; Nehl, Franzisca; Dorn, Jenny; Chalmers, Jeffrey J.; Zborowski, Maciej

    2014-01-01

    The emerging applications of biological cell separation to rare circulating tumor cell (CTC) detection and separation from blood rely on efficient methods of red blood cell (RBC) debulking. The two most widely used methods of centrifugation and RBC lysis have been associated with the concomitant significant losses of the cells of interest (such as progenitor cells or circulating tumor cells). Moreover, RBC centrifugation and lysis are not well adapted to the emerging diagnostic applications, relying on microfluidics and micro-scale total analytical systems. Therefore, magnetic RBC separation appears a logical alternative considering the high iron content of the RBC (normal mean 105 fg) as compared to the white blood cell iron content (normal mean 1.6 fg). The typical magnetic forces acting on a RBC are small, however, as compared to typical forces associated with centrifugation or the forces acting on synthetic magnetic nanoparticles used in current magnetic cell separations. This requires a significant effort in designing and fabricating a practical magnetic RBC separator. Applying advanced designs to the low cost, high power permanent magnets currently available, and building on the accumulated knowledge of the immunomagnetic cell separation methods and devices, an open gradient magnetic red blood cell (RBC) sorter was designed, fabricated and tested on label-free cell mixtures, with potential applications to RBC debulking from whole blood samples intended for diagnostic tests. PMID:24910468

  11. Autophagic vesicles on mature human reticulocytes explain phosphatidylserine-positive red cells in sickle cell disease.

    PubMed

    Mankelow, Tosti J; Griffiths, Rebecca E; Trompeter, Sara; Flatt, Joanna F; Cogan, Nicola M; Massey, Edwin J; Anstee, David J

    2015-10-01

    During maturation to an erythrocyte, a reticulocyte must eliminate any residual organelles and reduce its surface area and volume. Here we show this involves a novel process whereby large, intact, inside-out phosphatidylserine (PS)-exposed autophagic vesicles are extruded. Cell surface PS is a well-characterized apoptotic signal initiating phagocytosis. In peripheral blood from patients after splenectomy or in patients with sickle cell disease (SCD), the number of circulating red cells exposing PS on their surface is elevated. We show that in these patients PS is present on the cell surface of red cells in large (∼1.4 µm) discrete areas corresponding to autophagic vesicles. The autophagic vesicles found on reticulocytes are identical to those observed on red cells from splenectomized individuals and patients with SCD. Our data suggest the increased thrombotic risk associated with splenectomy, and patients with hemoglobinopathies is a possible consequence of increased levels of circulating mature reticulocytes expressing inside-out PS-exposed autophagic vesicles because of asplenia.

  12. Increased cholesterol and decreased fluidity of red cell membranes (spur cell anemia) in progressive intrahepatic cholestasis.

    PubMed

    Balistreri, W F; Leslie, M H; Cooper, R A

    1981-04-01

    Progressive hemolytic anemia occurred in a 4 1/2-year-old girl with familial intrahepatic cholestasis; a peripheral smear contained bizarre spiculated "spur" red cells. Analysis of this patient's fresh red cells revealed a 59% increase in cholesterol content with a normal phospholipid content and therefore an increase in the cholesterol/phospholipid molar ratio to 1.35 (normal = 0.92). A similar abnormality of lipid composition was present in serum lipoproteins. The lipid abnormality in red cell membrane was associated with a decrease in membrane fluidity, as assessed by the fluorescence polarization of the hydrophobic probe 1,6-diphenyl-1,3,5-hexatriene. Following incubation with patient's plasma, normal cells acquired a spur-shaped morphology with an associated decrease in osmotic fragility and a 25% increase in cholesterol content. The patient's cells, during incubation with normal plasma, acquired morphologic features of spiculated spherocytes with an increase in osmotic fragility and a 21% decrease in cholesterol content. Chenodeoxycholate and lithocholate were present in markedly elevated concentrations in serum. These studies show that a process identical to spur cell anemia in alcoholic cirrhosis may accompany severe liver disease in children with intrahepatic cholestasis.

  13. A ten liter stacked microbial desalination cell packed with mixed ion-exchange resins for secondary effluent desalination.

    PubMed

    Zuo, Kuichang; Cai, Jiaxiang; Liang, Shuai; Wu, Shijia; Zhang, Changyong; Liang, Peng; Huang, Xia

    2014-08-19

    The architecture and performance of microbial desalination cell (MDC) have been significantly improved in the past few years. However, the application of MDC is still limited in a scope of small-scale (milliliter) reactors and high-salinity-water desalination. In this study, a large-scale (>10 L) stacked MDC packed with mixed ion-exchange resins was fabricated and operated in the batch mode with a salt concentration of 0.5 g/L NaCl, a typical level of domestic wastewater. With circulation flow rate of 80 mL/min, the stacked resin-packed MDC (SR-MDC) achieved a desalination efficiency of 95.8% and a final effluent concentration of 0.02 g/L in 12 h, which is comparable with the effluent quality of reverse osmosis in terms of salinity. Moreover, the SR-MDC kept a stable desalination performance (>93%) when concentrate volume decreased from 2.4 to 0.1 L (diluate/concentrate volume ratio increased from 1:1 to 1:0.04), where only 0.875 L of nonfresh water was consumed to desalinate 1 L of saline water. In addition, the SR-MDC achieved a considerable desalination rate (95.4 mg/h), suggesting a promising application for secondary effluent desalination through deriving biochemical electricity from wastewater.

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

    PubMed

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

    2016-01-12

    Liposomes are nanoscale containers that are typically synthesized from lipids using a high-shear process such as extrusion or sonication. While liposomes are extensively used in drug delivery, they do suffer from certain problems including limited colloidal stability and short circulation times in the body. As an alternative to liposomes, we explore a class of container structures derived from erythrocytes (red blood cells). The procedure involves emptying the inner contents of these cells (specifically hemoglobin) and resuspending the empty structures in buffer, followed by sonication. The resulting structures are termed nanoerythrosomes (NERs), i.e., they are membrane-covered nanoscale containers, much like liposomes. Cryo-transmission electron microscopy (cryo-TEM) and small-angle neutron scattering (SANS) are employed for the first time to study these NERs. The results reveal that the NERs are discrete spheres (∼110 nm diameter) with a unilamellar membrane of thickness ∼4.5 nm. Remarkably, the biconcave disc-like shape of erythrocytes is also exhibited by the NERs under hypertonic conditions. Moreover, unlike typical liposomes, NERs show excellent colloidal stability in both buffer as well as in serum at room temperature, and are also able to withstand freeze-thaw cycling. We have explored the potential for using NERs as colloidal vehicles for targeted delivery. Much like conventional liposomes, NER membranes can be decorated with fluorescent or other markers, solutes can be encapsulated in the cores of the NERs, and NERs can be targeted to specifically bind to mammalian cells. Our study shows that NERs are a promising and versatile class of nanostructures. NERs that are harvested from a patient's own blood and reconfigured for nanomedicine can potentially offer several benefits including biocompatibility, minimization of immune response, and extended circulation time in the body. PMID:26684218

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

    NASA Astrophysics Data System (ADS)

    Sharma, S. K.

    2012-12-01

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

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

    PubMed

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

    2014-06-01

    The transfusion of red blood cells from umbilical cord blood (cord RBCs) is gathering significant interest for the treatment of fetal and neonatal anemia, due to its high content of fetal hemoglobin as well as numerous other potential benefits to fetuses and neonates. However, in order to establish a stable supply of cord RBCs for clinical use, a cryopreservation method must be developed. This, in turn, requires knowledge of the osmotic parameters of cord RBCs. Thus, the objective of this study was to characterize the osmotic parameters of cord RBCs: osmotically inactive fraction (b), hydraulic conductivity (Lp), permeability to cryoprotectant glycerol (Pglycerol), and corresponding Arrhenius activation energies (Ea). For Lp and Pglycerol determination, RBCs were analyzed using a stopped-flow system to monitor osmotically-induced RBC volume changes via intrinsic RBC hemoglobin fluorescence. Lp and Pglycerol were characterized at 4°C, 20°C, and 35°C using Jacobs and Stewart equations with the Ea calculated from the Arrhenius plot. Results indicate that cord RBCs have a larger osmotically inactive fraction compared to adult RBCs. Hydraulic conductivity and osmotic permeability to glycerol of cord RBCs differed compared to those of adult RBCs with the differences dependent on experimental conditions, such as temperature and osmolality. Compared to adult RBCs, cord RBCs had a higher Ea for Lp and a lower Ea for Pglycerol. This information regarding osmotic parameters will be used in future work to develop a protocol for cryopreserving cord RBCs. PMID:24727610

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

    PubMed

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

    2016-09-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2012-11-01

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

  19. Red blood cell phenotype matching for various ethnic groups.

    PubMed

    Badjie, Karafa S W; Tauscher, Craig D; van Buskirk, Camille M; Wong, Clare; Jenkins, Sarah M; Smith, Carin Y; Stubbs, James R

    2011-01-01

    Patients requiring chronic transfusion support are at risk of alloimmunization after red blood cell (RBC) transfusion because of a disparity between donor and recipient antigen profiles. This research explored the probability of obtaining an exact extended phenotype match between blood donors randomly selected from our institution and patients randomly selected from particular ethnic groups. Blood samples from 1,000 blood donors tested by molecular method were evaluated for the predicted phenotype distribution of Rh, Kell, Kidd, Duffy, and MNS. A random subsample of 800 donor phenotypes was then evaluated for the probability of obtaining an exact match with respect to phenotype with a randomly selected patient from a particular ethnic group. Overall, there was a greater than 80 percent probability of finding an exact donor-recipient match for the K/k alleles in the Kell system. The probability ranged from 3 percent to 38 percent, depending on the ethnicity and disparities in phenotypic profiles, for the Rh, Kidd, Duffy, and MNS systems. A significant donor-recipient phenotype mismatch ratio exists with certain blood group antigens such that, with current routine ABO and D matching practices, recipients of certain ethnic groups are predisposed to alloimmunization. PMID:22356481

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

    PubMed Central

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

    2015-01-01

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

  1. Neonatal nucleated red blood cells in G6PD deficiency.

    PubMed

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

    2002-05-01

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

  2. Red blood cell parameters in antenatal nonsickling hemoglobinopathy screening

    PubMed Central

    Bencaiova, Gabriela; Dapoto, Kristina; Zimmermann, Roland; Krafft, Alexander

    2015-01-01

    Objective To find a hematological parameter and the cut-off level for identification of nonsickling hemoglobinopathies in pregnant women. Materials and methods Venous blood samples of 849 women with singleton pregnancies were collected at the first visit. All women who met inclusion criteria were examined for nonsickling hemoglobinopathy. On the basis of the sensitivity and the specificity of different cut-off levels for hematological parameters, we calculated the optimal clinically practicable parameter for screening of nonsickling hemoglobinopathies in pregnant women. Results On the basis of the sensitivity and the specificity, the best screening parameters for the identification of nonsickling hemoglobinopathies among nonanemic pregnant women are mean corpuscular volume (MCV) with cut-off ≤80 fL (Youden’s index 91.2%), mean corpuscular hemoglobin (MCH) <27.5 pg (Youden’s index 90.7%), and microcytosis (MRC) ≥3% (Youden’s index 90.2%). An analysis using receiver operating characteristic curves and the calculated Youden’s index showed that MCV ≤76 fL, MCH ≤24 pg, or MRC ≥10% are the best red blood cell indices for the screening of nonsickling hemoglobinopathy among anemic women with iron deficiency. Conclusion Our results suggest targeted screening for nonsickling hemoglobinopathies in nonanemic pregnant women with MCV ≤80 fL, MCH ≤27.5 pg, or MRC ≥3% and in anemic women with MCV ≤76 fL, MCH ≤24 pg, or MRC ≥10%. PMID:25914560

  3. Neonatal nucleated red blood cells in G6PD deficiency.

    PubMed

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

    2002-05-01

    The objective of this study is to study the absolute number of nucleated red blood cells (RBC) at birth, an index of active fetal erythropoiesis, in infants with G6PD deficiency and in controls. We tested the hypothesis that hematocrit and hemoglobin would be lower, and absolute nucleated RBC counts higher, in the G6PD deficient and that these changes would be more prominent in infants exposed passively to fava bean through maternal diet. Thirty-two term infants with G6PD deficiency were compared with 30 term controls. Complete blood counts with manual differential counts were obtained within 12 hours of life. Absolute nucleated RBC and corrected leukocyte counts were computed from the Coulter results and the differential count. G6PD deficient patients did not differ from controls in terms of gestational age, birth weight, or Apgar scores or in any of the hematologic parameters studied, whether or not the mother reported fava beans consumption in the days prior to delivery. Although intrauterine hemolysis is possible in G6PD deficient fetuses exposed passively to fava beans, our study supports that such events must be very rare. PMID:12012283

  4. Amyloid β Levels in Human Red Blood Cells

    PubMed Central

    Kiko, Takehiro; Nakagawa, Kiyotaka; Satoh, Akira; Tsuduki, Tsuyoshi; Furukawa, Katsutoshi; Arai, Hiroyuki; Miyazawa, Teruo

    2012-01-01

    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 PMID:23166730

  5. Research Opportunities to Improve Neonatal Red Blood Cell Transfusion.

    PubMed

    Patel, Ravi Mangal; Meyer, Erin K; Widness, John A

    2016-10-01

    Red blood cell (RBC) transfusion is a common and lifesaving therapy for anemic neonates and infants, particularly among those born prematurely or undergoing surgery. However, evidence-based indications for when to administer RBCs and adverse effects of RBC transfusion on important outcomes including necrotizing enterocolitis, survival, and long-term neurodevelopmental impairment remain uncertain. In addition, blood-banking practices for preterm and term neonates and infants have been largely developed using studies from older children and adults. Use of and refinements in emerging technologies and advances in biomarker discovery and neonatal-specific RBC transfusion databases may allow clinicians to better define and tailor RBC transfusion needs and practices to individual neonates. Decreasing the need for RBC transfusion and developing neonatal-specific approaches in the preparation of donor RBCs have potential for reducing resource utilization and cost, improving outcomes, and assuring blood safety. Finally, large donor-recipient-linked cohort studies can provide data to better understand the balance of the risks and benefits of RBC transfusion in neonates. These studies may also guide the translation of new research into best practices that can rapidly be integrated into routine care. This review highlights key opportunities in transfusion medicine and neonatology for improving the preparation and transfusion of RBCs into neonates and infants. We focus on timely, currently addressable knowledge gaps that can increase the safety and efficacy of preterm and term neonatal and infant RBC transfusion practices.

  6. Research Opportunities to Improve Neonatal Red Blood Cell Transfusion.

    PubMed

    Patel, Ravi Mangal; Meyer, Erin K; Widness, John A

    2016-10-01

    Red blood cell (RBC) transfusion is a common and lifesaving therapy for anemic neonates and infants, particularly among those born prematurely or undergoing surgery. However, evidence-based indications for when to administer RBCs and adverse effects of RBC transfusion on important outcomes including necrotizing enterocolitis, survival, and long-term neurodevelopmental impairment remain uncertain. In addition, blood-banking practices for preterm and term neonates and infants have been largely developed using studies from older children and adults. Use of and refinements in emerging technologies and advances in biomarker discovery and neonatal-specific RBC transfusion databases may allow clinicians to better define and tailor RBC transfusion needs and practices to individual neonates. Decreasing the need for RBC transfusion and developing neonatal-specific approaches in the preparation of donor RBCs have potential for reducing resource utilization and cost, improving outcomes, and assuring blood safety. Finally, large donor-recipient-linked cohort studies can provide data to better understand the balance of the risks and benefits of RBC transfusion in neonates. These studies may also guide the translation of new research into best practices that can rapidly be integrated into routine care. This review highlights key opportunities in transfusion medicine and neonatology for improving the preparation and transfusion of RBCs into neonates and infants. We focus on timely, currently addressable knowledge gaps that can increase the safety and efficacy of preterm and term neonatal and infant RBC transfusion practices. PMID:27424006

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

    PubMed

    Ellis, Steven R; Lipton, Jeffrey M

    2008-01-01

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

  8. Alteration of red blood cell aggregation during blood storage

    NASA Astrophysics Data System (ADS)

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

    2011-06-01

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

  9. Red blood cell phenotype matching for various ethnic groups.

    PubMed

    Badjie, Karafa S W; Tauscher, Craig D; van Buskirk, Camille M; Wong, Clare; Jenkins, Sarah M; Smith, Carin Y; Stubbs, James R

    2011-01-01

    Patients requiring chronic transfusion support are at risk of alloimmunization after red blood cell (RBC) transfusion because of a disparity between donor and recipient antigen profiles. This research explored the probability of obtaining an exact extended phenotype match between blood donors randomly selected from our institution and patients randomly selected from particular ethnic groups. Blood samples from 1,000 blood donors tested by molecular method were evaluated for the predicted phenotype distribution of Rh, Kell, Kidd, Duffy, and MNS. A random subsample of 800 donor phenotypes was then evaluated for the probability of obtaining an exact match with respect to phenotype with a randomly selected patient from a particular ethnic group. Overall, there was a greater than 80 percent probability of finding an exact donor-recipient match for the K/k alleles in the Kell system. The probability ranged from 3 percent to 38 percent, depending on the ethnicity and disparities in phenotypic profiles, for the Rh, Kidd, Duffy, and MNS systems. A significant donor-recipient phenotype mismatch ratio exists with certain blood group antigens such that, with current routine ABO and D matching practices, recipients of certain ethnic groups are predisposed to alloimmunization.

  10. Red blood cell aggregation and microcirculation in rat cremaster muscle.

    PubMed

    Vicaut, E; Hou, X; Decuypère, L; Taccoen, A; Duvelleroy, M

    1994-01-01

    Using intravital microscopy of the rat cremaster muscle, we studied the effects of changing red blood cell (RBC) aggregation on RBC arteriolar velocity and perfused capillary density (PCD). To modify RBC aggregation, 2 and/or 10% dextran (molecular weights 40,000, 70,000 or 480,000) or fresh rat plasma was infused into adult male rats via a normovolemic hemodilution procedure. The high-molecular-weight dextrans (70,000 and 480,000) both induced RBC hyperaggregation associated with similar dose-dependent decreases in RBC arteriolar velocity (30 and 40% for dextran concentrations of 2 and 10%, respectively) and in PCD (35 and 37%, respectively, for the two concentrations). Conversely, with 40,000 molecular weight dextran or plasma, we observed a 30% increase in RBC arteriolar velocity, but no change in PCD or hyperaggregation. Intravenous injection of the antiaggregating drug troxerutin (10(-3) M), either before or after 2% dextran 70,000, significantly inhibited the effects of this dextran on RBC arteriolar velocity and on PCD. We conclude that RBC hyperaggregation can lead to changes in both arteriolar velocity and PCD and may, therefore, impair tissue oxygenation.

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

    NASA Astrophysics Data System (ADS)

    Noguchi, Hiroshi

    2010-06-01

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

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

    PubMed

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

    2015-01-01

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

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

    PubMed

    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.

  14. Characterization of Red Blood Cells with Multiwavelength Transmission Spectroscopy

    PubMed Central

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

    2015-01-01

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

  15. Elastic area compressibility modulus of red cell membrane.

    PubMed Central

    Evans, E A; Waugh, R; Melnik, L

    1976-01-01

    Micropipette measurements of isotropic tension vs. area expansion in pre-swollen single human red cells gave a value of 288 +/- 50 SD dyn/cm for the elastic, area compressibility modulus of the total membrane at 25 degrees C. This elastic constant, characterizing the resistance to area expansion or compression, is about 4 X 10(4) times greater than the elastic modulus for shear rigidity; therefore, in situations where deformation of the membrane does not require large isotropic tensions (e.g., in passage through normal capillaries), the membrane can be treated by a simple constitutive relation for a two-dimensionally, incompressible material (i.e. fixed area). The tension was found to be linear and reversible for the range of area changes observed (within the experimental system resolution of 10%). The maximum fractional area expansion required to produce lysis was uniformly distributed between 2 and 4% with 3% average and 0.7% SD. By heating the cells to 50 degrees C, it appears that the structural matrix (responsible for the shear rigidity and most of the strength in isotropic tension) is disrupted and primarily the lipid bilayer resists lysis. Therefore, the relative contributions of the structural matrix and lipid bilayer to the elastic, area compressibility could be estimated. The maximum isotropic tension at 25 degrees C is 10-12 dyn/cm and at 50 degrees C is between 3 and 4 dyn/cm. From this data, the respective compressibilities are estimated at 193 dyn/cm and 95 dyn/cm for structural network and bilayer. The latter value correlates well with data on in vitro, monolayer surface pressure versus area curves at oil-water interfaces. Images FIGURE 2 PMID:1276386

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

    PubMed

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

    2013-04-01

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

  17. Serum concentrations of micronutrients, packed cell volume, and blood hemoglobin during the first two gestations and lactations of sows.

    PubMed Central

    Girard, C L; Robert, S; Matte, J J; Farmer, C; Martineau, G P

    1996-01-01

    The objective of the present work was to describe the changes in serum concentrations of some micronutrients during the first 2 gestations and lactations of 33 gilts in order to establish blood reference values for a rapid assessment of nutritional status. In both parities, blood samples were taken from the jugular vein at mating, 5, 10 and 15 wk of gestation and l d and 4 wk after parturition (weaning). Reference values (mean, standard deviation, minimum, maximum) for serum folates, vitamin B12, vitamin B6 metabolites (pyridoxal and pyridoxal-5-phosphate), calcium, phosphorus, sodium, zinc, copper and iron, as well as blood hemoglobin and packed cell volume are reported for each studied time. Differences between parities and between each time are also reported. Results from the present report demonstrate that knowledge of the physiological state of the sows is critical for the assessment of nutritional status of an individual or a breeding herd by interpretation of analyses of blood constituents. PMID:8809380

  18. Monoclonal antibodies directed against human Rh antigens in tests with the red cells of nonhuman primates.

    PubMed

    Socha, W W; Ruffie, J

    1990-01-01

    Monoclonal antibodies against Rh related antigens on human red cells often crossreact with the red cells of the highest subhuman primate species. Depending on specificity of antibody, the species tested, and technique used, these reactions can be either species-specific or type specific. In tests with chimpanzee red cells, some of the latter type reactions have specificities related to the R antigen of the R-C-E-F blood group system of chimpanzee; specificities of some others seem to be unrelated to any known chimpanzee blood groups. Monoclonal anti-D reagents that give uniformly positive reactions with human D-positive (common and rare types) red cells, display wide individual differences in tests with chimpanzee blood. This indicates that there are minute structural variations of antibody molecules from one monoclonal anti-D antibodies apparently have no bearing on recognition of the D combining site on the human red cells, but come into play when in contact with chimpanzee rbcs. Some of the monoclonal antibodies directed against Rh and LW molecules are distinguished by unusually strong reactions with the red cells of the Old World monkeys (macaques and baboons), which is in contrast with negative or weak reactions of the same antibodies with the red cells of anthropoid apes and human bloods. One may recall, that polyclonal anti-Rh sera do not react with the blood of rhesus monkeys, the phenomenon that was the source of controversy surrounding the discovery of the rhesus factor of the human blood.

  19. Ethanol induces human red cell shape transformations and enhanced ligand-mediated agglutinability

    SciTech Connect

    Weinstein, R.S.; McLawhon, R.W.; Marikovsky, Y.

    1986-03-01

    Ethanol concentrations are markedly elevated in rat stomach wall when ulcerogenic doses of 100 % ethanol (2 ml for 5 to 10 minutes) are instilled in rat gastric lumen. The authors observed that red cells in gastric mucosal postcapillary venules become spiculated and interadherent under these conditions. The authors have now studied this phenomenon in vitro using washing human red cells. Concentrations of high grade ethanol ranging from 2 to 10% (v/v) in physiological buffered saline (pH 7.3) without Ca/sup + +/ or Mg/sup + +/ at 25/sup 0/C rapidly transformed human red cells into spiculated forms. 2% ethanol transformed human red cells into disco-echinocytes in 15 min. whereas 10% ethanol transformed red blood cells into echinocytes within 3 min. Washing out of ethanol at 1 hour reverted the echinocytes into discocytes. However, following 3 hours of incubation in 10% ethanol washing out of ethanol produced stomatocytes. The ethanol-induced echinocytic shape transformations were accompanied by a dose-related increase in red cell agglutinability with poly-L-lysine or the plant lectin wheat germ agglutinin. The enhanced agglutinability was reversed by restoring the red cell shape changes and alterations in surface properties may play a role in the pathogenesis of ethanol-induced gastric ulcers.

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

    PubMed

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

    2016-04-01

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

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

    PubMed

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

    2016-04-01

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

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

    PubMed Central

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

    2015-01-01

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

  3. Identification, purification and reconstitution of thiamin metabolizing enzymes in human red blood cells.

    PubMed

    Egi, Y; Koyama, S; Shioda, T; Yamada, K; Kawasaki, T

    1992-11-20

    Thiamin and its mono- (TMP), di- (TDP) and triphosphate (TTP) were assayed in adult human whole blood using high-performance liquid chromatography (HPLC). TDP and TTP were detected in red blood cells (RBC), but not in plasma. After incubation with 20 microM thiamin and 5 mM glucose for 2 h, the TDP and TTP contents of RBC increased from 111 to 222 and 0.6 to 2.2 nmol/l of packed RBC, respectively, suggesting enzymatic conversion of thiamin to TDP and then to TTP. Thiamin pyrophosphokinase (TPK, EC 2.7.6.2) had not been isolated before from human materials, nor had cytosolic adenylate kinase (AK1, EC 2.7.4.3) in human RBC been demonstrated to catalyze the phosphorylation of TDP to TTP, although AK1 from pig and chicken skeletal muscle possess TTP-synthesizing activity. TPK and AK1 in a human RBC lysate were therefore purified by a series of the conventional techniques. The specific activity of the purified TPK, which was obtained as a single protein, was 720 nmol TDP formed/mg protein per h at 37 degrees C. A partially purified AK1 preparation catalyzed the formation of TTP from TDP (specific activity, 170 nmol/mg protein per h at 37 degrees C) in addition to its proper reaction to form ATP from ADP. After incubation of the purified TPK and AK1 with 20 microM thiamin in the presence of ATP, ADP and Mg2+ at 37 degrees C for 48 h, the amounts of TDP and TTP synthesized were 465 and 54.0 pmol/250 microliters reaction mixture, respectively. Neither TDP nor TTP was formed when TPK was omitted from the reaction mixture and an omission of AK1 resulted in the formation of TDP alone. These results indicate that thiamin is converted to TDP by TPK and, subsequently, to TTP by AK1 in human RBC.

  4. Membrane characteristics and osmotic fragility of red cells, fractionated with anglehead centrifugation and counterflow centrifugation.

    PubMed

    van der Vegt, S G; Ruben, A M; Werre, J M; de Gier, J; Staal, G E

    1985-11-01

    Red cell populations were separated on the basis of differences in density using anglehead centrifugation and on the basis of differences in mean cell volume using counterflow centrifugation. In the different fractions, mean surface area was calculated, phospholipid and cholesterol content determined as well as the osmotic behaviour in hypotonic salt solutions. Older red cells appeared to be more resistant to hypotonic salt solutions, due to favourable surface area to volume ratio. PMID:4063204

  5. Enhancement of heat transfer in red cell suspensions in vitro experiments.

    PubMed

    Carr, R T; Tiruvaloor, N R

    1989-05-01

    New data on laminar heat convection with red cell suspensions have been gathered for both heating and cooling. When compared to data for the suspending medium alone, it is apparent that the red cells enhance laminar heat transfer when Pe greater than 4. This is probably due to particle movements. These new data disagree with earlier studies which indicated no enhancement of heat transfer for blood cell suspensions. The data do agree with previous correlations for enhanced thermal transport in sheared suspensions.

  6. Quantitative Absorption Cytometry for Measuring Red Blood Cell Hemoglobin Mass and Volume

    PubMed Central

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

    2015-01-01

    We present an optical system, called the quantitative absorption cytometer (QAC), to measure the volume and hemoglobin mass of red blood cells flowing through a microfluidic channel. In contrast to clinical hematology analyzers, where cells are sphered in order for both volume and hemoglobin to be measured accurately, the QAC measures cells in their normal physiological shape. Human red blood cells are suspended in a refractive index-matching absorbing buffer, driven through a microfluidic channel, and imaged using a transmission light microscope onto a color camera. A red and a blue LED illuminate cells and images at each color are used to independently retrieve cell volume and hemoglobin mass. This system shows good agreement with red blood cell indices retrieved by a clinical hematology analyzer and in fact measures a smaller coefficient of variation of hemoglobin concentration. In addition to cell indices, the QAC returns height and mass maps of each measured cell. These quantitative images are valuable for analyzing the detailed morphology of individual cells as well as statistical outliers found in the data. We also measured red blood cells in hypertonic and hypotonic buffers to quantify the correlation between volume and hemoglobin mass under osmotic stress. Because this method is invariant to cell shape, even extremely nonspherical cells in hypertonic buffers can be measured accurately. PMID:24677669

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

    PubMed Central

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

    2013-01-01

    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. Compared to other cell therapies transfusion poses the unique challenge of requiring great cell doses (2.5 × 1012 cells vs 107 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. PMID:22177597

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

    SciTech Connect

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

    1980-07-01

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

  9. Evaluation of red blood cell labelling methods based on a statistical model for red blood cell survival.

    PubMed

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

    2011-12-21

    The aim of this work is to compare different labelling methods that are commonly used to estimate the lifespan of red blood cells (RBCs), e.g. in anaemia of renal failure, where the effect of treatment with erythropoietin depends on the lifespan of RBCs. A previously developed model for the survival time of RBCs that accounts for plausible physiological processes of RBC destruction was used to simulate ideal random and cohort labelling methods for RBCs, as well as the flaws associated with these methods (e.g. reuse of label and loss of the label from the surviving RBCs). Random labelling with radioactive chromium and cohort labelling using heavy nitrogen were considered. Blood sampling times were determined for RBC survival studies using both labelling methods by applying the theory of optimal design. It was assessed whether the underlying parameter values of the model are estimable from these studies, and the precision of the parameter estimates were calculated. In theory, parameter estimation would be possible for both types of ideal labelling methods without flaws. However, flaws associated with random labelling are significant and not all parameters controlling RBC survival in the model can be estimated with good precision. In contrast, cohort labelling shows good precision in the parameter estimates even in the presence of reuse and prolonged incorporation of the label. A model based analysis of RBC survival studies is recommended in future to account for limitations in methodology as well as likely causes of RBC destruction. PMID:21945607

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

    PubMed

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

    2016-09-12

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

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

    PubMed

    Grau, Marijke; Kollikowski, Alexander; Bloch, Wilhelm

    2016-09-12

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

  12. Rheological properties of RBC in the microcirculation of mammalian skeletal muscle. [red blood cells

    NASA Technical Reports Server (NTRS)

    Ehrenberg, M. H.

    1974-01-01

    In the investigation the established technique of direct microscopic viewing was combined with the use of a closed circuit television system and cinematography. The red cell flow patterns in all capillaries were found to be oscillatory with characteristic cycle frequencies and amplitudes for all concentrations of inspired oxygen greater than 8%. Generally, there was a transient decrease in mean flow rate with increasing severity of hypoxia, with a gradual return toward control values. Red cell flow patterns are discussed along with questions of red cell configuration.

  13. Detection of IgG sensitization of red cells with /sup 125/I staphylococcal protein A

    SciTech Connect

    Yam, P.; Petz, L.D.; Spath, P.

    1982-06-01

    Most cases of immune hemolytic anemia are associated with a positive direct antiglobulin test. However, in some cases, the antiglobulin test is not sensitive enough to detect low levels of red-cell bound antibodies. This report describes a method using radiolabelled purified staphylococcal protein A which is capable of detecting IgG sensitization of red cells beyond the threshold of serologic techniques. It is less cumbersome than previously described methods and does not require antibody purification procedures. Its effectiveness was demonstrated for the detection of red-cell alloantibodies and in evaluation of patients with acquired hemolytic anemias associated with a negative direct antiglobulin test.

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

    NASA Astrophysics Data System (ADS)

    Braunmüller, S.; Schmid, L.; Franke, T.

    2011-05-01

    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 Ly/vm≈2.2 × 10 - 3 s with channel width Ly and red blood cell velocity vm. 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.

  15. Update on extracellular vesicles inside red blood cell storage units: Adjust the sails closer to the new wind.

    PubMed

    Antonelou, Marianna H; Seghatchian, Jerard

    2016-08-01

    Release of vesicles from cells is a universal biological system, an adaptive cellular response to endogenous or external physiological or stressful stimuli and a genius means for intercellular, inter-organ and even inter-organism communication. These secreted vesicles that are collectively designated extracellular vesicles (EVs) have increasingly attracted the interest of cell biologists due to their imaginable interactions with every piece of the known biological systems in both health and disease states. Although EVs isolation and characterization are challenges, owing to their particular physicochemical features and complex biology, recent technological innovation has offered better understanding and inevitably, driven the revision of previously established theories on them. However, a crucial question remains unsolved: the physiological relevance of EVs in vivo. Since membrane vesiculation is an integral part of red blood cell (RBC) aging and homeostatic machinery and a prominent feature of RBC storage lesion, the characterization of storage EVs and their probable clinical relevance with the therapeutic or adverse effects of transfusions are extremely important targets in the research fields of transfusion biology and medicine. The scientists involved should transfer nascent knowledge and state-of-the-art technological tools in the packed RBC unit in order to: (i) update the inventory of biochemical and biophysical features of storage EVs; (ii) gain insight into the molecular pathways/signals underlying their generation; and (iii) clarify their dependence on blood donor, storage strategies and analytical variations, in order to step forward on understanding their interactions with stored or recipient target cells. PMID:27452642

  16. Update on extracellular vesicles inside red blood cell storage units: Adjust the sails closer to the new wind.

    PubMed

    Antonelou, Marianna H; Seghatchian, Jerard

    2016-08-01

    Release of vesicles from cells is a universal biological system, an adaptive cellular response to endogenous or external physiological or stressful stimuli and a genius means for intercellular, inter-organ and even inter-organism communication. These secreted vesicles that are collectively designated extracellular vesicles (EVs) have increasingly attracted the interest of cell biologists due to their imaginable interactions with every piece of the known biological systems in both health and disease states. Although EVs isolation and characterization are challenges, owing to their particular physicochemical features and complex biology, recent technological innovation has offered better understanding and inevitably, driven the revision of previously established theories on them. However, a crucial question remains unsolved: the physiological relevance of EVs in vivo. Since membrane vesiculation is an integral part of red blood cell (RBC) aging and homeostatic machinery and a prominent feature of RBC storage lesion, the characterization of storage EVs and their probable clinical relevance with the therapeutic or adverse effects of transfusions are extremely important targets in the research fields of transfusion biology and medicine. The scientists involved should transfer nascent knowledge and state-of-the-art technological tools in the packed RBC unit in order to: (i) update the inventory of biochemical and biophysical features of storage EVs; (ii) gain insight into the molecular pathways/signals underlying their generation; and (iii) clarify their dependence on blood donor, storage strategies and analytical variations, in order to step forward on understanding their interactions with stored or recipient target cells.

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

    SciTech Connect

    Bitensky, M.; Yoshida, Tatsuro

    1996-04-01

    The project sought to develop methods to extend the storage life of red blood cells. Extended storage would allow donor to self or autologous transfusion, expand and stabilize the blood supply, reduce the cost of medical care and eliminate the risk of transfusion related infections, including a spectrum of hepatitides (A, B and C) and HIV. The putative cause of red blood cell spoilage at 4 C has been identified as oxidative membrane damage resulting from deoxyhemoglobin and its denaturation products including hemichrome, hemin and Fe{sup 3+}. Trials with carbon monoxide, which is a stabilizer of hemoglobin, have produced striking improvement of red blood cell diagnostics for cells stored at 4 C. Carbonmonoxy hemoglobin is readily converted to oxyhemoglobin by light in the presence of oxygen. These findings have generated a working model and an approach to identify the best protocols for optimal red cell storage and hemoglobin regeneration.

  18. RD2-MolPack-Chim3, a Packaging Cell Line for Stable Production of Lentiviral Vectors for Anti-HIV Gene Therapy

    PubMed Central

    Stornaiuolo, Anna; Piovani, Bianca Maria; Bossi, Sergio; Zucchelli, Eleonora; Corna, Stefano; Salvatori, Francesca; Mavilio, Fulvio; Bordignon, Claudio; Rizzardi, Gian Paolo

    2013-01-01

    Abstract Over the last two decades, several attempts to generate packaging cells for lentiviral vectors (LV) have been made. Despite different technologies, no packaging clone is currently employed in clinical trials. We developed a new strategy for LV stable production based on the HEK-293T progenitor cells; the sequential insertion of the viral genes by integrating vectors; the constitutive expression of the viral components; and the RD114-TR envelope pseudotyping. We generated the intermediate clone PK-7 expressing constitutively gag/pol and rev genes and, by adding tat and rd114-tr genes, the stable packaging cell line RD2-MolPack, which can produce LV carrying any transfer vector (TV). Finally, we obtained the RD2-MolPack-Chim3 producer clone by transducing RD2-MolPack cells with the TV expressing the anti-HIV transgene Chim3. Remarkably, RD114-TR pseudovirions have much higher potency when produced by stable compared with transient technology. Most importantly, comparable transduction efficiency in hematopoietic stem cells (HSC) is obtained with 2-logs less physical particles respect to VSV-G pseudovirions produced by transient transfection. Altogether, RD2-MolPack technology should be considered a valid option for large-scale production of LV to be used in gene therapy protocols employing HSC, resulting in the possibility of downsizing the manufacturing scale by about 10-fold in respect to transient technology. PMID:23767932

  19. RD2-MolPack-Chim3, a packaging cell line for stable production of lentiviral vectors for anti-HIV gene therapy.

    PubMed

    Stornaiuolo, Anna; Piovani, Bianca Maria; Bossi, Sergio; Zucchelli, Eleonora; Corna, Stefano; Salvatori, Francesca; Mavilio, Fulvio; Bordignon, Claudio; Rizzardi, Gian Paolo; Bovolenta, Chiara

    2013-08-01

    Over the last two decades, several attempts to generate packaging cells for lentiviral vectors (LV) have been made. Despite different technologies, no packaging clone is currently employed in clinical trials. We developed a new strategy for LV stable production based on the HEK-293T progenitor cells; the sequential insertion of the viral genes by integrating vectors; the constitutive expression of the viral components; and the RD114-TR envelope pseudotyping. We generated the intermediate clone PK-7 expressing constitutively gag/pol and rev genes and, by adding tat and rd114-tr genes, the stable packaging cell line RD2-MolPack, which can produce LV carrying any transfer vector (TV). Finally, we obtained the RD2-MolPack-Chim3 producer clone by transducing RD2-MolPack cells with the TV expressing the anti-HIV transgene Chim3. Remarkably, RD114-TR pseudovirions have much higher potency when produced by stable compared with transient technology. Most importantly, comparable transduction efficiency in hematopoietic stem cells (HSC) is obtained with 2-logs less physical particles respect to VSV-G pseudovirions produced by transient transfection. Altogether, RD2-MolPack technology should be considered a valid option for large-scale production of LV to be used in gene therapy protocols employing HSC, resulting in the possibility of downsizing the manufacturing scale by about 10-fold in respect to transient technology.

  20. Sickle cell disease biochip: a functional red blood cell adhesion assay for monitoring sickle cell disease

    PubMed Central

    ALAPAN, YUNUS; KIM, CEONNE; ADHIKARI, ANIMA; GRAY, KAYLA E.; GURKAN-CAVUSOGLU, EVREN; LITTLE, JANE A.; GURKAN, UMUT A.

    2016-01-01

    Sickle cell disease (SCD) afflicts millions of people worldwide and is associated with considerable morbidity and mortality. Chronic and acute vaso-occlusion are the clinical hallmarks of SCD and can result in pain crisis, widespread organ damage, and early movtality. Even though the molecular underpinnings of SCD were identified more than 60 years ago, there are no molecular or biophysical markers of disease severity that are feasibly measured in the clinic. Abnormal cellular adhesion to vascular endothelium is at the root of vaso-occlusion. However, cellular adhesion is not currently evaluated clinically. Here, we present a clinically applicable microfluidic device (SCD biochip) that allows serial quantitative evaluation of red blood cell (RBC) adhesion to endothelium-associated protein-immobilized microchannels, in a closed and preprocessing-free system. With the SCD biochip, we have analyzed blood samples from more than 100 subjects and have shown associations between the measured RBC adhesion to endothelium-associated proteins (fibronectin and laminin) and individual RBC characteristics, including hemoglobin content, fetal hemoglobin concentration, plasma lactate dehydrogenase level, and reticulocyte count. The SCD biochip is a functional adhesion assay, reflecting quantitative evaluation of RBC adhesion, which could be used at baseline, during crises, relative to various long-term complications, and before and after therapeutic interventions. PMID:27063958

  1. 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.

    PubMed

    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.

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

    NASA Technical Reports Server (NTRS)

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

    1980-01-01

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

  3. Diffusional water permeability of mammalian red blood cells.

    PubMed

    Benga, G; Borza, T

    1995-12-01

    An extensive programme of comparative nuclear magnetic resonance measurements of the membrane diffusional permeability for water (Pd) and of the activation energy (Ea,d) of this process in red blood cells (RBCs) from 21 mammalian species was carried out. On the basis of Pd, these species could be divided into three groups. First, the RBC's from humans, cow, sheep and "large" kangaroos (Macropus giganteus and Macropus rufus) had Pd values approximately 5 x 10(-3) cm/s at 25 degrees and 7 x 10(-3) cm/s at 37 degrees C. The RBCs from other marsupial species, mouse, rat, guinea pig and rabbit, had Pd values roughly twice higher, whereas echidna RBCs were twice lower than human RBCs. The value of Ea,d was in most cases correlated with the values of Pd. A value of Ea,d approximately 26 kJ/mol was found for the RBCs from humans and the species having similar Pd values. Low values of Ea,d (ranging from 15 to 22 kJ/mol) appeared to be associated with relatively high values of Pd. The highest values of Ea,d (33 kJ/mol) was found in echidna RBCs. This points to specialized channels for water diffusion incorporated in membrane proteins; a relatively high water permeability of the RBC membrane could be due to a greater number of channel proteins. There are, however, situations where a very high water permeability of RBCs is associated with a high value of Ea,d (above 25 kJ/mol) as in the case of RBCs from mouse, rat and tree kangaroo. Moreover, it was found that Pd in different species was positively correlated to the RBC membrane phosphatidylcholine and negatively correlated to the sphingomyelin content. This suggests that in addition to the number of channel proteins, other factors are involved in the water permeability of the RBC membrane.

  4. Red Cell Properties after Different Modes of Blood Transportation

    PubMed Central

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

    2016-01-01

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

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

    PubMed

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

    2016-09-01

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

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

    PubMed

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

    2016-01-01

    Transportation of blood samples is unavoidable for assessment of specific parameters in blood of patients with rare anemias, blood doping testing, or for research purposes. Despite the awareness that shipment may substantially alter multiple parameters, no study of that extent has been performed to assess these changes and optimize shipment conditions to reduce transportation-related artifacts. Here we investigate the changes in multiple parameters in blood of healthy donors over 72 h of simulated shipment conditions. Three different anticoagulants (K3EDTA, Sodium Heparin, and citrate-based CPDA) for two temperatures (4°C and room temperature) were tested to define the optimal transportation conditions. Parameters measured cover common cytology and biochemistry parameters (complete blood count, hematocrit, morphological examination), red blood cell (RBC) volume, ion content and density, membrane properties and stability (hemolysis, osmotic fragility, membrane heat stability, patch-clamp investigations, and formation of micro vesicles), Ca(2+) handling, RBC metabolism, activity of numerous enzymes, and O2 transport capacity. Our findings indicate that individual sets of parameters may require different shipment settings (anticoagulants, temperature). Most of the parameters except for ion (Na(+), K(+), Ca(2+)) handling and, possibly, reticulocytes counts, tend to favor transportation at 4°C. Whereas plasma and intraerythrocytic Ca(2+) cannot be accurately measured in the presence of chelators such as citrate and EDTA, the majority of Ca(2+)-dependent parameters are stabilized in CPDA samples. Even in blood samples from healthy donors transported using an optimized shipment protocol, the majority of parameters were stable within 24 h, a condition that may not hold for the samples of patients with rare anemias. This implies for as short as possible shipping using fast courier services to the closest expert laboratory at reach. Mobile laboratories or the travel of the

  7. Vesiculation of healthy and defective red blood cells

    NASA Astrophysics Data System (ADS)

    Li, He; Lykotrafitis, George

    2015-07-01

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

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

    PubMed

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

    2016-01-01

    Transportation of blood samples is unavoidable for assessment of specific parameters in blood of patients with rare anemias, blood doping testing, or for research purposes. Despite the awareness that shipment may substantially alter multiple parameters, no study of that extent has been performed to assess these changes and optimize shipment conditions to reduce transportation-related artifacts. Here we investigate the changes in multiple parameters in blood of healthy donors over 72 h of simulated shipment conditions. Three different anticoagulants (K3EDTA, Sodium Heparin, and citrate-based CPDA) for two temperatures (4°C and room temperature) were tested to define the optimal transportation conditions. Parameters measured cover common cytology and biochemistry parameters (complete blood count, hematocrit, morphological examination), red blood cell (RBC) volume, ion content and density, membrane properties and stability (hemolysis, osmotic fragility, membrane heat stability, patch-clamp investigations, and formation of micro vesicles), Ca(2+) handling, RBC metabolism, activity of numerous enzymes, and O2 transport capacity. Our findings indicate that individual sets of parameters may require different shipment settings (anticoagulants, temperature). Most of the parameters except for ion (Na(+), K(+), Ca(2+)) handling and, possibly, reticulocytes counts, tend to favor transportation at 4°C. Whereas plasma and intraerythrocytic Ca(2+) cannot be accurately measured in the presence of chelators such as citrate and EDTA, the majority of Ca(2+)-dependent parameters are stabilized in CPDA samples. Even in blood samples from healthy donors transported using an optimized shipment protocol, the majority of parameters were stable within 24 h, a condition that may not hold for the samples of patients with rare anemias. This implies for as short as possible shipping using fast courier services to the closest expert laboratory at reach. Mobile laboratories or the travel of the

  9. Red cell and platelet concentrates from blood collected into half-strength citrate anticoagulant: improved maintenance of red cell 2,3-diphosphoglycerate in half-citrate red cells.

    PubMed

    Farrugia, A; Douglas, S; James, J; Whyte, G

    1992-01-01

    This study confirms previous work suggesting equivalent in vitro properties in blood components prepared from donations collected into half-citrate preservative (HCPD) compared to components derived from donations collected into standard citrate-phosphate-dextrose (CPD) preservatives. In addition, red cell products harvested from HCPD donations showed significantly improved maintenance of pH over storage, and this was reflected in improved maintenance of intracellular 2,3-diphosphoglycerate (2,3-DPG). This effect was observed in whole blood and in red cells suspended in a phosphate-containing additive solution (Tuta AAS). Collection into HCPD also improved 2,3-DPG maintenance in red cell concentrates processed following an 18-hour hold at 22 degrees C. These improvements were less pronounced in red cells suspended in a non-phosphate-containing medium (Fenwal Adsol) in which a higher pH was maintained even in units collected in CPD. Platelets harvested from HCPD blood and suspended in plasma showed equivalent quality to platelets from standard donations. Some deterioration of platelet properties was observed when HCPD platelets were stored in a non-citrate synthetic medium. Together with data indicating improved coagulation factor stability, these results suggest that collection into HCPD improves stored blood quality and may also allow logistical benefits in blood component preparation.

  10. Increased phorbol 12,13-dibutyrate (PDBu) receptor function associated with sickle red cell membrane ghosts

    SciTech Connect

    Ramachandran, M.; Nair, C.N.; Abraham, E.C.

    1987-05-01

    The biological receptor for tumor-promoting phorbol esters has been identified as the CaS /phospholipid dependent enzyme, protein kinase C. In the red cell, this enzyme is mainly cytosolic but becomes translocated to the membrane if the cellular CaS is allowed to rise. Since cellular CaS in sickle red cells is high, it was reasoned that this enzyme may become more membrane-bound. In fact, the authors noticed a four-fold increase in the binding of TH-PDBu by membrane ghosts isolated from sickle red cells compared to normal red cells (pmoles PDBu bound/mg protein; normal = 0.3 vs sickle cell = 1.4). Attempts to assay the enzyme directly as phospholipid-activated TSP incorporation into the acid-precipitable membrane proteins also indicated a two-fold increase in the radiolabelling of sickle cell membrane ghosts. Autophosphorylation of membrane proteins and analysis of the phosphorylation profile by SDS-PAGE and autoradiography revealed phosphorylation predominantly of bands 3, 4.1 and 4.9 which are known protein kinase C substrates for the red cell enzyme. The increased membrane-associated protein kinase C in sickle red cells may have a bearing on the altered membrane properties reported in this condition.

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

    PubMed

    Gambaruto, Alberto M

    2016-07-26

    Vessel with 'circular' or 'star-shaped' cross sections are studied, representing respectively dilated or constricted cases where endothelial cells smoothly line or bulge into the lumen. Computational haemodynamics simulations are carried out on idealised periodic arteriole-sized vessels, with red blood cell 'tube' hematocrit value=24%. A further simulation of a single red blood cell serves for comparison purposes. The bulk motion of the red blood cells reproduces well-known effects, including the presence of a cell-free layer and the apparent shear-thinning non-Newtonian rheology. The velocity flow field is analysed in a Lagrangian reference frame, relative to any given red blood cell, hence removing the bulk coaxial motion and highlighting instead the complex secondary flow patterns. An aggregate formation becomes apparent, continuously rearranging and dynamic, brought about by the inter-cellular fluid mechanics interactions and the deformability properties of the cells. The secondary flow field induces a vacillating radial migration of the red blood cells. At different radial locations, the red blood cells express different residence times, orientation and shape. The shear stresses exerted by the flow on the vessel wall are influenced by the motion of red blood cells, despite the presence of the cell-free layer. Spatial (and temporal) variations of wall shear stress patters are observed, especially for the 'circular' vessel. The 'star-shaped' vessel bears considerable stress at the protruding endothelial cell crests, where the stress vectors are coaxially aligned. The bulging endothelial cells hence regularise the transmission of stresses on the vessel wall. PMID:26822224

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

    PubMed

    Gambaruto, Alberto M

    2016-07-26

    Vessel with 'circular' or 'star-shaped' cross sections are studied, representing respectively dilated or constricted cases where endothelial cells smoothly line or bulge into the lumen. Computational haemodynamics simulations are carried out on idealised periodic arteriole-sized vessels, with red blood cell 'tube' hematocrit value=24%. A further simulation of a single red blood cell serves for comparison purposes. The bulk motion of the red blood cells reproduces well-known effects, including the presence of a cell-free layer and the apparent shear-thinning non-Newtonian rheology. The velocity flow field is analysed in a Lagrangian reference frame, relative to any given red blood cell, hence removing the bulk coaxial motion and highlighting instead the complex secondary flow patterns. An aggregate formation becomes apparent, continuously rearranging and dynamic, brought about by the inter-cellular fluid mechanics interactions and the deformability properties of the cells. The secondary flow field induces a vacillating radial migration of the red blood cells. At different radial locations, the red blood cells express different residence times, orientation and shape. The shear stresses exerted by the flow on the vessel wall are influenced by the motion of red blood cells, despite the presence of the cell-free layer. Spatial (and temporal) variations of wall shear stress patters are observed, especially for the 'circular' vessel. The 'star-shaped' vessel bears considerable stress at the protruding endothelial cell crests, where the stress vectors are coaxially aligned. The bulging endothelial cells hence regularise the transmission of stresses on the vessel wall.

  13. Genetic studies of water buffalo blood markers. I. Red cell acid phosphatase, albumin, catalase, red cell alpha-esterase-3, group-specific component, and protease inhibitor.

    PubMed

    Tan, S G; Barker, J S; Selvaraj, O S; Mukherjee, T K; Wong, Y F

    1993-06-01

    We have developed the methodologies for typing and family studies to establish the modes of inheritance of water buffalo red cell acid phosphatase (Acp), protease inhibitor (Pi), and group-specific component (Gc) on isoelectric focusing and albumin (Alb), red cell alpha-esterase-3 (Est-3), and catalase (Cat) on polyacrylamide gel electrophoresis. Family studies showed that Pi, Gc, Alb, and Cat are coded by autosomal genes with two codominant alleles, while Est-3 is autosomal with two codominant alleles and a recessive null allele and Acp exhibits three codominant alleles.

  14. Proteomic analysis identifies differentially expressed proteins after red propolis treatment in Hep-2 cells.

    PubMed

    Frozza, Caroline Olivieri da Silva; Ribeiro, Tanara da Silva; Gambato, Gabriela; Menti, Caroline; Moura, Sidnei; Pinto, Paulo Marcos; Staats, Charley Christian; Padilha, Francine Ferreira; Begnini, Karine Rech; de Leon, Priscila Marques Moura; Borsuk, Sibele; Savegnago, Lucielli; Dellagostin, Odir; Collares, Tiago; Seixas, Fabiana Kömmling; Henriques, João Antonio Pêgas; Roesch-Ely, Mariana

    2014-01-01

    Here we investigated alterations in the protein profile of Hep-2 treated with red propolis using two-dimensional electrophoresis associated to mass spectrometry and apoptotic rates of cells treated with and without red propolis extracts through TUNEL and Annexin-V assays. A total of 325 spots were manually excised from the two-dimensional gel electrophoresis and 177 proteins were identified using LC-MS-MS. Among all proteins identified that presented differential expression, most were down-regulated in presence of red propolis extract at a concentration of 120 μg/mL (IC50): GRP78, PRDX2, LDHB, VIM and TUBA1A. Only two up-regulated proteins were identified in this study in the non-cytotoxic (6 μg/mL) red propolis treated group: RPLP0 and RAD23B. TUNEL staining assay showed a markedly increase in the mid- to late-stage apoptosis of Hep-2 cells induced by red propolis at concentrations of 60 and 120 μg/mL when compared with non-treated cells. The increase of late apoptosis was confirmed by in situ Annexin-V analysis in which red propolis extract induced late apoptosis in a dose-dependent manner. The differences in tumor cell protein profiles warrant further investigations including isolation of major bioactive compounds of red propolis in different cell lines using proteomics and molecular tests to validate the protein expression here observed.

  15. Biosignatures of Kerala red rain cells: Implications in understanding their origin

    NASA Astrophysics Data System (ADS)

    Gangappa, R.; Thomas, M.; Hogg, S.

    2013-09-01

    The red rain that fell over Kerala, southern India (2001-2012) was characterised by the red pigmented particles. Earlier proposal claiming that these are known algal bloom blown from trees (Sampath et al, 2001; DiGregorio, 2007) has been studied by us and disproved. Also, further investigation reporting their extraordinary properties including a suggestion that they lack DNA (Louis and Kumar 2003; 2006; 2008) has been invalidated (Gangappa and Hogg, 2013). However, their claim regarding the growth and replication of these cells at 300ºC needs more investigation if it is to gain acceptance. Current study provide evidences regarding the biological properties of Kerala red rain cells to gain insights into environmental conditions from which they may have originated. Combined with various research strategies and high resolution instruments, we have demonstrated the following interesting properties of Kerala red rain cells: (1) unusually thick external envelope enclosing the central core; (2)stability of red pigment at temperatures about 100ºC and pH variations; (3) absence of eukaryotic ultrastructures; (4) possible replication at 121ºC with nanostructures (possible daughter cells) having similar morphological features inside the large mother cells at such high temperature. They contain high percentage of carbon, iron, silicon and aluminum and often enclosed in a silicon rich biofilms. Further investigation shows that the positive detection of DNA in these cells was possible only after the complete removal of red pigment, thereby providing an explanation for the negative outcome of earlier studies in this regard. Moreover, evidences are shown to support that these cells contain high amounts of UV absorbing compounds, porphyrin complexes and possible scytonemin. Kerala red rain cells may prove to be polyextermophiles belonging to prokaryotes and may have possibly originated from the environment containing above mentioned chemical elements, high energy UV exposure and

  16. The functional importance of blood group-active molecules in human red blood cells.

    PubMed

    Anstee, D J

    2011-01-01

    Antigens of 23 of the 30 human blood group systems are defined by the amino acid sequence of red cell membrane proteins. The antigens of DI, RH, RHAG, MNS, GE and CO systems are carried on blood group-active proteins (Band 3, D and CE polypeptides, RhAG, Glycophorins A and B, Glycophorins C and D and Aquaporin 1, respectively) which are expressed at high levels (>200,000 copies/red cell). These major proteins contribute to essential red cell functions either directly as membrane transporters and by providing linkage to the underlying red cell skeleton or by facilitating the membrane assembly of the protein complexes involved in these processes. The proteins expressing antigens of the remaining 17 blood group systems are much less abundant (<20,000 copies/red cell) and their functional importance for the circulating red cell is largely unknown. Human gene knock-outs (null phenotypes) have been described for many of these minor blood group-active proteins, but only absence of Kx glycoprotein has been clearly linked with pathology directly related to the function of circulating red cells. Recent evidence suggesting the normal quality control system for glycoprotein synthesis is altered during the latter stages of red cell production raises the possibility that many of these low abundance blood group-active proteins are vestigial. In sickle cell disease and polycythaemia vera, elevated Lutheran glycoprotein expression may contribute to pathology. Dyserythropoiesis with reduced antigen expression can result from mutations in the erythroid transcription factors GATA-1 and EKLF.

  17. Relative Transport Behavior of Escherichia coli O157:H7 and Salmonella enterica serovar Pullorum in Packed Bed Column Systems: Influence of Solution Chemistry and Cell Concentration

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The influence of solution chemistry and cell concentration on bacterial pathogen transport has been examined using Salmonella pullorum and Escherichia coli O157:H7. A packed bed column was employed to determine the transport behavior and deposition kinetics on real aquifer sand particles over a ran...

  18. Ruthenium red-induced bundling of bacterial cell division protein, FtsZ.

    PubMed

    Santra, Manas Kumar; Beuria, Tushar K; Banerjee, Abhijit; Panda, Dulal

    2004-06-18

    The assembly of FtsZ plays a major role in bacterial cell division, and it is thought that the assembly dynamics of FtsZ is a finely regulated process. Here, we show that ruthenium red is able to modulate FtsZ assembly in vitro. In contrast to the inhibitory effects of ruthenium red on microtubule polymerization, we found that a substoichiometric concentration of ruthenium red strongly increased the light-scattering signal of FtsZ assembly. Further, sedimentable polymer mass was increased by 1.5- and 2-fold in the presence of 2 and 10 microm ruthenium red, respectively. In addition, ruthenium red strongly reduced the GTPase activity and prevented dilution-induced disassembly of FtsZ polymers. Electron microscopic analysis showed that 4-10 microm of ruthenium red produced thick bundles of FtsZ polymers. The significant increase in the light-scattering signal and pelletable polymer mass in the presence of ruthenium red seemed to be due to the bundling of FtsZ protofilaments into larger polymers rather than the actual increase in the level of polymeric FtsZ. Furthermore, ruthenium red was found to copolymerize with FtsZ, and the copolymerization of substoichiometric amounts of ruthenium red with FtsZ polymers promoted cooperative assembly of FtsZ that produced large bundles. Calcium inhibited the binding of ruthenium red to FtsZ. However, a concentration of calcium 1000-fold higher than that of ruthenium red was required to produce similar effects on FtsZ assembly. Ruthenium red strongly modulated FtsZ polymerization, suggesting the presence of an important regulatory site on FtsZ and suggesting that a natural ligand, which mimics the action of ruthenium red, may regulate the assembly of FtsZ in bacteria.

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

    DOEpatents

    Bitensky, M.W.; Yoshida, Tatsuro

    1997-04-29

    A method is disclosed using oxygen removal for extending the useful shelf-life of refrigerated red blood cells. A cost-effective, 4 C storage procedure that preserves red cell quality and prolongs post-transfusion in vivo survival is described. Preservation of adenosine triphosphate levels and reduction in hemolysis and in membrane vesicle production of red blood cells stored at 4 C for prolonged periods of time is achieved by removing oxygen from the red blood cells at the time of storage; in particular, by flushing with an inert gas. Adenosine triphosphate levels of the stored red blood cells are boosted in some samples by addition of ammonium phosphate. 4 figs.

  20. Molecular packing and solar cell performance in blends of polymers with a bisadduct fullerene.

    PubMed

    Miller, Nichole Cates; Sweetnam, Sean; Hoke, Eric T; Gysel, Roman; Miller, Chad E; Bartelt, Jonathan A; Xie, Xinxin; Toney, Michael F; McGehee, Michael D

    2012-03-14

    We compare the solar cell performance of several polymers with the conventional electron acceptor phenyl-C61-butyric acid methyl ester (PCBM) to fullerenes with one to three indene adducts. We find that the multiadduct fullerenes with lower electron affinity improve the efficiency of the solar cells only when they do not intercalate between the polymer side chains. When they intercalate between the side chains, the multiadduct fullerenes substantially reduce solar cell photocurrent. We use X-ray diffraction to determine how the fullerenes are arranged within crystals of poly-(2,5-bis(3-tetradecylthiophen-2-yl)thieno[3,2-b]thiophene) (PBTTT) and suggest that poor electron transport in the molecularly mixed domains may account for the reduced solar cell performance of blends with fullerene intercalation.

  1. Monomeric Garnet, a far-red fluorescent protein for live-cell STED imaging.

    PubMed

    Hense, Anika; Prunsche, Benedikt; Gao, Peng; Ishitsuka, Yuji; Nienhaus, Karin; Nienhaus, G Ulrich

    2015-12-09

    The advancement of far-red emitting variants of the green fluorescent protein (GFP) is crucially important for imaging live cells, tissues and organisms. Despite notable efforts, far-red marker proteins still need further optimization to match the performance of their green counterparts. Here we present mGarnet, a robust monomeric marker protein with far-red fluorescence peaking at 670 nm. Thanks to its large extinction coefficient of 95,000 M(-1)cm(-1), mGarnet can be efficiently excited with 640-nm light on the red edge of its 598-nm excitation band. A large Stokes shift allows essentially the entire fluorescence emission to be collected even with 640-nm excitation, counterbalancing the lower fluorescence quantum yield of mGarnet, 9.1%, that is typical of far-red FPs. We demonstrate an excellent performance as a live-cell fusion marker in STED microscopy, using 640 nm excitation and 780 nm depletion wavelengths.

  2. Light scattering by red blood cells in ektacytometry: Fraunhofer versus anomalous diffraction.

    PubMed

    Streekstra, G J; Hoekstra, A G; Nijhof, E J; Heethaar, R M

    1993-05-01

    In the present literature on ektacytometry, small angle light scattering by ellipsoidal red blood cells is commonly approximated by Fraunhofer diffraction. Calculations on a sphere with the size and relative refractive index of a red cell, however, show that Fraunhofer diffraction deviates significantly from exact Mie theory. Anomalous diffraction is found to be a much better approximation. The anomalous diffraction theory is used to calculate the intensity distribution of the light scattered by an ellipsoidally deformed red blood cell. The derived expression shows that the ellipticity of isointensity curves in forward scattered light are equal to the ellipticity of the red blood cell. The theoretical expression is fitted to the intensity patterns measured with an ektacytometer. For the small observation angles used in ektacytometry, the experimental results confirm the validity of the anomalous diffraction approach.

  3. Visualization of cutaneous hemangioma with Tc-99m tagged red blood cells

    SciTech Connect

    Gordon, L.; Vujic, I.; Spicer, K.M.

    1981-10-01

    Scintigraphy with Tc-99m labeled red blood cells (RBCs) was used to evaluate a patient with a large cutaneous hemangioma. The usefulness of this procedure when combined with arteriography is discussed.

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

    PubMed

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

    2015-07-27

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

  5. In vitro red blood cell assay for oxidant toxicity of petroleum oil

    SciTech Connect

    Couillard, C.M.; Leighton, F.A. )

    1993-05-01

    Petroleum oil has caused hemolytic anemia in birds and mammals. In birds, an oxidant damage on circulating red cells has been identified as the primary toxic effect of ingested petroleum oils. An in vitro red blood cell assay was developed to discriminate among the oxidant activities of different petroleum oils. The assay used rabbit red blood cells with a rat liver enzyme system and formation of methemoglobin was measured as an indicator of oxidant damage to the red cells. The assay was applied to five different petroleum oils and to naphthalene, a petroleum hydrocarbon known to cause hemolytic anemia. Different petroleum oils differed in their capacity to induce methemoglobin formation. Methemoglobin levels varied from 2.9% with Arabian light crude oil to 6.2% with South Louisiana crude oil. Naphthalene induced formation of up to 37% methemoglobin. Naphthalene and the five petroleum oils generated methemoglobin only in the presence of liver enzymes.

  6. A strong antibody reacting with enzyme modified E positive red blood cells.

    PubMed

    Heistø, H; Fagerhol, M K

    1979-01-01

    A high titer antibody was discovered in a healthy young man of blood group A1 R2r. The antibody strongly agglutinated all E positive red blood cells including his own, which had been modified by papain, ficin and bromelin, but only very weakly when modified by trypsin. The antibody was shown to be an IgM antibody. It did not react with unmodified red blood cells.

  7. A strong antibody reacting with enzyme modified E positive red blood cells.

    PubMed

    Heistø, H; Fagerhol, M K

    1979-01-01

    A high titer antibody was discovered in a healthy young man of blood group A1 R2r. The antibody strongly agglutinated all E positive red blood cells including his own, which had been modified by papain, ficin and bromelin, but only very weakly when modified by trypsin. The antibody was shown to be an IgM antibody. It did not react with unmodified red blood cells. PMID:116398

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

    NASA Astrophysics Data System (ADS)

    Fontes, A.; Barjas Castro, M. L.; Brandão, M. M.; Fernandes, H. P.; Thomaz, A. A.; Huruta, R. R.; Pozzo, L. Y.; Barbosa, L. C.; Costa, F. F.; Saad, S. T. O.; Cesar, C. L.

    2011-04-01

    Optical tweezers are a very sensitive tool, based on photon momentum transfer, for individual, cell by cell, manipulation and measurements, which can be applied to obtain important properties of erythrocytes for clinical and research purposes. Mechanical and electrical properties of erythrocytes are critical parameters for stored cells in transfusion centers, immunohematological tests performed in transfusional routines and in blood diseases. In this work, we showed methods, based on optical tweezers, to study red blood cells and applied them to measure apparent overall elasticity, apparent membrane viscosity, zeta potential, thickness of the double layer of electrical charges and adhesion in red blood cells.

  9. Use of the Primitive Unit Cell in Understanding Subtle Features of the Cubic Closest-Packed Structure

    ERIC Educational Resources Information Center

    Hawkins, John A.; Rittenhouse, Jeffrey L.; Soper, Linda M.; Rittenhouse, Robert C.

    2008-01-01

    One of the most important crystal structures adopted by metals is characterized by the "abcabc"...stacking of close-packed layers. This structure is commonly referred to in textbooks as the cubic close-packed (ccp) or face-centered cubic (fcc) structure, since the entire lattice can be generated by replication of a face-centered cubic unit cell…

  10. Serological distinction of A antigen between red blood cells and saliva in blood grouping of blood and body fluid stains.

    PubMed

    Sagisaka, K; Iwasa, M; Yokoi, T

    1984-02-01

    A antigens of red blood cells and body fluids such as saliva, semen and sweat could be serologically distinguished using rabbit or guinea pig immune anti-A. As for antisera specific for red blood cell A, A+ rabbits were intravenously immunized with A group red blood cells. The resulting antisera were absorbed with O and B red cells and with A. Se saliva. The absorbed anti-A reacted with A red cells (titer 1:32) and was not inhibited with A. Se saliva. Guinea pigs were intramuscularly injected with A. Se saliva. Crude antisera contained agglutinins to human red cells which were abolished by absorption with A red cells. After absorption with O. Se saliva, the antisera were proved to have agglutinin activity with A group saliva using latex coated with A. Se saliva. A antigens from blood or body fluid stains could be distinguished by the elution method with these anti-A sera. PMID:6719447

  11. Fibroblast cell line establishment, cryopreservation and interspecies embryos reconstruction in red panda ( Ailurus fulgens).

    PubMed

    Tao, Yong; Liu, Jianming; Zhang, Yunhai; Zhang, Meiling; Fang, Junshun; Han, Wei; Zhang, Zhizhong; Liu, Ya; Ding, Jianping; Zhang, Xiaorong

    2009-05-01

    In evolution, the red panda (Ailurus fulgens) plays a pivotal role in the higher level phylogeny of arctoides carnivore mammals. The red panda inhabits certain Asian countries only and its numbers are decreasing. Therefore, the development of feasible ways to preserve this species is necessary. Genetic resource cryopreservation and somatic cell nuclear transfer (SCNT) have been used extensively to rescue this endangered species. The present study describes the establishment, for the first time, of a red panda ear fibroblast cell line, which was then cryopreserved, thawed and cultured. Through micromanipulation, interspecies embryos were reconstructed using the cryopreserved-thawed fibroblasts of the red panda as the donor and rabbit oocytes as recipients. A total of 194 enucleated rabbit oocytes were reconstructed with red panda ear fibroblasts; enucleated oocytes were activated without fusion as the control. The results show that the fibroblast cell line was established successfully by tissue culture and then cryopreserved in liquid nitrogen. Supplementation with 20% fetal bovine serum and 8% dimethyl sulphoxide in basic medium facilitated the cryopreservation. The interspecies embryos were successfully reconstructed. The cleavage, morulae and blastocyst rates after in vitro culture were 71, 47 and 23% (31/194), respectively. This study indicated that a somatic cell line could be established and cryopreserved from red panda and that rabbit cytoplast supports mitotic cleavage of the red panda karyoplasts and is capable of reprogramming the nucleus to achieve blastocysts.

  12. Anti-galactose antibodies do not bind to normal human red cells

    SciTech Connect

    Kay, M.M.B.; Bosman, G.J.C.G.M.

    1986-03-01

    The authors investigated the possibility that senescent cell IgG might have an anti-galactose (anti-gal) specificity as suggested by others. Anti-gal was isolated from normal human serum with ..cap alpha.. melibiose-agarose. The assays used were hemagglutination, rosetting, phagocytosis, and /sup 125/I protein A binding assay, immunoblotting, and glycine/HCL, pH 2.3, versus sugar elutions. Results revealed binding of anti-gal to rabbit but not human RBC. Immunoblotting of anti-gal revealed labeling of approx.29 bands in rabbit red cell membranes and no labeling of autologous human red cell membranes. The authors attempted to inhibit binding of anti-gal with various sugars. Melibiose caused enhancement rather than inhibition of agglutination when used at concentrations reported by previous investigators to cause inhibition. Neither ..cap alpha.. melibiose or galactose caused inhibition of phagocytosis of senescent cells. Senescent cell IgG was not displaced from freshly isolated old red cells by incubation with melibiose or galactose as determined by an /sup 125/I protein A binding assay. The authors were also unable to elute IgG from stored red cells with galactose. The authors conclude that senescent cell IgG does not have an anti-galactose specificity. The authors were unable to demonstrate an anti-gal antibody to normal human red cells.

  13. The incomplete anti-Rh antibody agglutination mechanism of trypsinized ORh+ red cells.

    PubMed Central

    Margni, R A; Leoni, J; Bazzurro, M

    1977-01-01

    The capacity for binding to trypsinized and non-trypsinized ORh+ red cells, of the IgG incomplete anti-Rh antibody and its F(ab')2 and Fc fragments has been investigated. An analysis has also been made of the capacity of non-specific human IgG, aggregated non-specific human IgG, human IgM (19S) and IgM (7S), and of fragments Fcgamma, Fcmu and Fc5mu to inhibit the agglutination of trypsinized ORh+ red cells by the IgG incomplete anti-Rh antibody. The results obtained indicate that these antibodies behave in a similar manner to that of nonprecipitating antibodies, and that the agglutination of trypsinized red cells seems to be a mixed reaction due to the interaction of an Fab fragment with its Rh antigenic determinant present in the surface of a red cell and the Fc of the same molecule with a receptor for Fc present in adjacent red cells. The trypsin treatment apparently results in the liberation of occult Fc receptors. It has also been demonstrated that in the agglutination of ORh+ red cells by IgG incomplete anti-Rh antibody in the presence of albumin, interaction must occur in some manner between the albumin and the Fc fragment since the F(ab')2 fragment does not give rise to agglutination under such conditions. Images Figure 1 PMID:415968

  14. An integrated power pack of dye-sensitized solar cell and Li battery based on double-sided TiO2 nanotube arrays.

    PubMed

    Guo, Wenxi; Xue, Xinyu; Wang, Sihong; Lin, Changjian; Wang, Zhong Lin

    2012-05-01

    We present a new approach to fabricate an integrated power pack by hybridizing energy harvest and storage processes. This power pack incorporates a series-wound dye-sensitized solar cell (DSSC) and a lithium ion battery (LIB) on the same Ti foil that has double-sided TiO(2) nanotube (NTs) arrays. The solar cell part is made of two different cosensitized tandem solar cells based on TiO(2) nanorod arrays (NRs) and NTs, respectively, which provide an open-circuit voltage of 3.39 V and a short-circuit current density of 1.01 mA/cm(2). The power pack can be charged to about 3 V in about 8 min, and the discharge capacity is about 38.89 μAh under the discharge density of 100 μA. The total energy conversion and storage efficiency for this system is 0.82%. Such an integrated power pack could serve as a power source for mobile electronics.

  15. Thermal Characterization and Analysis of A123 Systems Battery Cells, Modules and Packs: Cooperative Research and Development Final Report, CRADA Number CRD-07-243

    SciTech Connect

    Pesaran, A.

    2012-03-01

    In support of the A123 Systems battery development program with USABC/DOE, NREL provided technical support in thermal characterization, analysis and management of batteries. NREL's effort was part of Energy Storage Project funded by DOE Vehicle Technologies Program. The purpose of this work was for NREL to perform thermal characterization and analysis of A123 Systems cells and modules with the aim for Al23 Systems to improve the thermal performance of their battery cells, modules and packs.

  16. Targeted Application of Human Genetic Variation Can Improve Red Blood Cell Production from Stem Cells.

    PubMed

    Giani, Felix C; Fiorini, Claudia; Wakabayashi, Aoi; Ludwig, Leif S; Salem, Rany M; Jobaliya, Chintan D; Regan, Stephanie N; Ulirsch, Jacob C; Liang, Ge; Steinberg-Shemer, Orna; Guo, Michael H; Esko, Tõnu; Tong, Wei; Brugnara, Carlo; Hirschhorn, Joel N; Weiss, Mitchell J; Zon, Leonard I; Chou, Stella T; French, Deborah L; Musunuru, Kiran; Sankaran, Vijay G

    2016-01-01

    Multipotent and pluripotent stem cells are potential sources for cell and tissue replacement therapies. For example, stem cell-derived red blood cells (RBCs) are a potential alternative to donated blood, but yield and quality remain a challenge. Here, we show that application of insight from human population genetic studies can enhance RBC production from stem cells. The SH2B3 gene encodes a negative regulator of cytokine signaling and naturally occurring loss-of-function variants in this gene increase RBC counts in vivo. Targeted suppression of SH2B3 in primary human hematopoietic stem and progenitor cells enhanced the maturation and overall yield of in-vitro-derived RBCs. Moreover, inactivation of SH2B3 by CRISPR/Cas9 genome editing in human pluripotent stem cells allowed enhanced erythroid cell expansion with preserved differentiation. Our findings therefore highlight the potential for combining human genome variation studies with genome editing approaches to improve cell and tissue production for regenerative medicine.

  17. Macrophage depletion by free bisphosphonates and zoledronate-loaded red blood cells.

    PubMed

    Sabatino, Raffaella; Antonelli, Antonella; Battistelli, Serafina; Schwendener, Reto; Magnani, Mauro; Rossi, Luigia

    2014-01-01

    Bisphosphonates, besides being important drugs for the treatment of various bone diseases, could also be used to induce apoptosis in macrophage-like and cancer cells. However, their activity in vivo is limited by a short plasma half-life and rapid uptake within bone. Therefore, several delivery systems have been proposed to modify their pharmacokinetic profile and biodistribution. Among these, red blood cells (RBCs) represent one of the most promising biological carriers. The aim of this study was to select the best performing compound among Clodronate, Pamidronate, Ibandronate and Zoledronate in killing macrophages and to investigate RBCs as innovative carrier system to selectively target bisphosphonates to macrophages. To this end, the encapsulation of the selected bisphosphonates in autologous RBCs as well as the effect on macrophages, both in vitro and in vivo were studied. This work shows that, among the tested bisphosphonates, Zoledronate has proven to be the most active molecule. Human and murine RBCs have been successfully loaded with Zoledronate by a procedure of hypotonic dialysis and isotonic resealing, obtaining a dose-dependent drug entrapment with a maximal loading of 7.96±2.03, 6.95±3.9 and 7.0±1.89 µmoles of Zoledronate/ml of packed RBCs for human, Swiss and Balb/C murine RBCs, respectively. Engineered RBCs were able to detach human and murine macrophages in vitro, leading to a detachment of 66±8%, 67±8% and 60.5±3.5% for human, Swiss and Balb/C RBCs, respectively. The in vivo efficacy of loaded RBCs was tested in Balb/C mice administering 59 µg/mouse of RBC-encapsulated Zoledronate. By a single administration, depletion of 29.0±16.38% hepatic macrophages and of 67.84±5.48% spleen macrophages was obtained, confirming the ability of encapsulated Zoledronate to deplete macrophages in vivo. In conclusion, RBCs loaded with Zoledronate should be considered a suitable system for targeted delivery to macrophages, both in vitro and in vivo.

  18. Macrophage Depletion by Free Bisphosphonates and Zoledronate-Loaded Red Blood Cells

    PubMed Central

    Sabatino, Raffaella; Antonelli, Antonella; Battistelli, Serafina; Schwendener, Reto; Magnani, Mauro; Rossi, Luigia

    2014-01-01

    Bisphosphonates, besides being important drugs for the treatment of various bone diseases, could also be used to induce apoptosis in macrophage-like and cancer cells. However, their activity in vivo is limited by a short plasma half-life and rapid uptake within bone. Therefore, several delivery systems have been proposed to modify their pharmacokinetic profile and biodistribution. Among these, red blood cells (RBCs) represent one of the most promising biological carriers. The aim of this study was to select the best performing compound among Clodronate, Pamidronate, Ibandronate and Zoledronate in killing macrophages and to investigate RBCs as innovative carrier system to selectively target bisphosphonates to macrophages. To this end, the encapsulation of the selected bisphosphonates in autologous RBCs as well as the effect on macrophages, both in vitro and in vivo were studied. This work shows that, among the tested bisphosphonates, Zoledronate has proven to be the most active molecule. Human and murine RBCs have been successfully loaded with Zoledronate by a procedure of hypotonic dialysis and isotonic resealing, obtaining a dose-dependent drug entrapment with a maximal loading of 7.96±2.03, 6.95±3.9 and 7.0±1.89 µmoles of Zoledronate/ml of packed RBCs for human, Swiss and Balb/C murine RBCs, respectively. Engineered RBCs were able to detach human and murine macrophages in vitro, leading to a detachment of 66±8%, 67±8% and 60.5±3.5% for human, Swiss and Balb/C RBCs, respectively. The in vivo efficacy of loaded RBCs was tested in Balb/C mice administering 59 µg/mouse of RBC-encapsulated Zoledronate. By a single administration, depletion of 29.0±16.38% hepatic macrophages and of 67.84±5.48% spleen macrophages was obtained, confirming the ability of encapsulated Zoledronate to deplete macrophages in vivo. In conclusion, RBCs loaded with Zoledronate should be considered a suitable system for targeted delivery to macrophages, both in vitro and in vivo. PMID

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

    NASA Astrophysics Data System (ADS)

    Zeidan, Adel; Yeheskely-Hayon, Daniella; Minai, Limor; Yelin, Dvir

    2016-03-01

    The properties of red blood cells are a remarkable indicator of the body's physiological condition; their density could indicate anemia or polycythemia, their absorption spectrum correlates with blood oxygenation, and their morphology is highly sensitive to various pathologic states including iron deficiency, ovalocytosis, and sickle cell disease. Therefore, measuring the morphology of red blood cells is important for clinical diagnosis, providing valuable indications on a patient's health. In this work, we simulated the appearance of normal red blood cells under a reflectance confocal microscope and discovered unique relations between the cells' morphological parameters and the resulting characteristic interference patterns. The simulation results showed good agreement with in vitro reflectance confocal images of red blood cells, acquired using spectrally encoded flow cytometry (SEFC) that imaged the cells during linear flow and without artificial staining. By matching the simulated patterns to the SEFC images of the cells, the cells' three-dimensional shapes were evaluated and their volumes were calculated. Potential applications include measurement of the mean corpuscular volume, cell morphological abnormalities, cell stiffness under mechanical stimuli, and the detection of various hematological diseases.

  20. American Recovery & Reinvestment Act: Fuel Cell Hybrid Power Packs and Hydrogen Refueling for Lift Trucks

    SciTech Connect

    Block, Gus

    2011-07-31

    HEB Grocery Company, Inc. (H-E-B) is a privately-held supermarket chain with 310 stores throughout Texas and northern Mexico. H-E-B converted 14 of its lift reach trucks to fuel cell power using Nuvera Fuel Cells’ PowerEdge™ units to verify the value proposition and environmental benefits associated with the technology. Issues associated with the increasing power requirements of the distribution center operation, along with high ambient temperature in the summer and other operating conditions (such as air quality and floor surface condition), surfaced opportunities for improving Nuvera’s PowerEdge fuel cell system design in high-throughput forklift environments. The project included on-site generation of hydrogen from a steam methane reformer, called PowerTap™ manufactured by Nuvera. The hydrogen was generated, compressed and stored in equipment located outside H-E-B’s facility, and provided to the forklifts by hydrogen dispensers located in high forklift traffic areas. The PowerEdge fuel cell units logged over 25,300 operating hours over the course of the two-year project period. The PowerTap hydrogen generator produced more than 11,100 kg of hydrogen over the same period. Hydrogen availability at the pump was 99.9%. H-E-B management has determined that fuel cell forklifts help alleviate several issues in its distribution centers, including truck operator downtime associated with battery changing, truck and battery maintenance costs, and reduction of grid electricity usage. Data collected from this initial installation demonstrated a 10% productivity improvement, which enabled H-E-B to make economic decisions on expanding the fleet of PowerEdge and PowerTap units in the fleet, which it plans to undertake upon successful demonstration of the new PowerEdge reach truck product. H-E-B has also expressed interst in other uses of hydrogen produced on site in the future, such as for APUs used in tractor trailers and refrigerated transport trucks in its fleet.

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

    NASA Astrophysics Data System (ADS)

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

    2010-05-01

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

  2. On the agglutinogens of red cells developed with proteolytic enzymes and neuraminidase.

    PubMed

    Sagisaka, K; Takahashi, K

    1976-10-01

    It has been known that the agglutinability of human red cells is changed or enhanced by treatments with proteolytic enzymes or neuraminidase. In this paper, the serological properties of agglutinogens developed by proteolytic enzymes (bromelin, ficin, papain, trypsin and pronase) and neuraminidase are investigated by using antisera to trypsin- and neuraminidase-treated red cells. The adsorptions of the antiserum to trypsinized red cells with the cells treated with each of the proteolytic enzymes showed that the agglutinogens uncovered by bromelin, ficin and papain were different from those by pronase and trypsin. It was demonstrated that pronase was the most effective enzyme to uncover the agglutinogen located on deeper site of red cell membrane. This was confirmed by the agglutination with the test cells treated twice with two kinds of the enzymes. The reactions of the antiserum to neuraminidase-treated red cells treated with six kinds of the enzymes indicated that the agglutinogens developed by neuraminidase resembled those by bromelin, ficin and papain more than those by trypsin and pronase. PMID:982434

  3. Radionuclide-labeled red blood cells: current status and future prospects

    SciTech Connect

    Srivastava, S.C.; Chervu, L.R.

    1984-04-01

    Radiolabeling of red cells and their clinical and research application in nuclear medicine constitute an area of continued interest and steady growth during the past two decades. Technetium-/sup 99/m-labeled red cells in particular have revolutionized the field of cardiovascular nuclear medicine by making possible the external evaluation of various heart parameters with minimum radiation dose or trauma to the patient. Among other areas of study that use /sup 99/mTc -RBC are blood pool imaging, detection of vascular malformations, red cell mass determination, detection of gastrointestinal bleeding, and of hemangiomas. Heat-damaged /sup 99/mTc -RBC find application in spleen imaging, accessory spleen localization, detection of GI bleeding, and in other areas. A critical evaluation is presented of the various in vitro and in vivo labeling techniques that are currently available for red cell labeling. Even though the presently used procedures provide satisfactory labeled preparations, ideal radioisotopic RBC labels remain to be developed. Intermediate (2-3 days) as well as long-lived (approximately 30 days) radionuclidic labels are highly desirable for a number of clinical procedures where /sup 99/mTc is not useful due to its short half-life. New approaches such as the use of radiolabeled antibodies to red cell antigens, or labeling specific receptor sites in the cell may lead to substantial improvements in the labeling methodology and could yield labeled cells with the least damage and maximum in vivo stability.

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

    PubMed

    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 < 0.05) in viscosity, elasticity and relaxation time at equivalent shear rates over seven weeks of storage indicating a decrease in RBC deformability. No statistically significant differences in RBC deformability or relaxation time were observed between male and female RBCs at any storage time. The decrease in RBC deformability during blood bank storage may reduce tissue perfusion and RBC lifespan in patients receiving blood bank RBCs.

  5. Dynamic quantitative photothermal monitoring of cell death of individual human red blood cells upon glucose depletion

    NASA Astrophysics Data System (ADS)

    Vasudevan, Srivathsan; Chen, George Chung Kit; Andika, Marta; Agarwal, Shuchi; Chen, Peng; Olivo, Malini

    2010-09-01

    Red blood cells (RBCs) have been found to undergo ``programmed cell death,'' or eryptosis, and understanding this process can provide more information about apoptosis of nucleated cells. Photothermal (PT) response, a label-free photothermal noninvasive technique, is proposed as a tool to monitor the cell death process of living human RBCs upon glucose depletion. Since the physiological status of the dying cells is highly sensitive to photothermal parameters (e.g., thermal diffusivity, absorption, etc.), we applied linear PT response to continuously monitor the death mechanism of RBC when depleted of glucose. The kinetics of the assay where the cell's PT response transforms from linear to nonlinear regime is reported. In addition, quantitative monitoring was performed by extracting the relevant photothermal parameters from the PT response. Twofold increases in thermal diffusivity and size reduction were found in the linear PT response during cell death. Our results reveal that photothermal parameters change earlier than phosphatidylserine externalization (used for fluorescent studies), allowing us to detect the initial stage of eryptosis in a quantitative manner. Hence, the proposed tool, in addition to detection of eryptosis earlier than fluorescence, could also reveal physiological status of the cells through quantitative photothermal parameter extraction.

  6. Plasticity of Cells and Ex Vivo Production of Red Blood Cells

    PubMed Central

    Hiroyama, Takashi; Miharada, Kenichi; Kurita, Ryo; Nakamura, Yukio

    2011-01-01

    The supply of transfusable red blood cells (RBCs) is not sufficient in many countries. If transfusable RBCs could be produced abundantly from certain resources, it would be very useful. Our group has developed a method to produce enucleated RBCs efficiently from hematopoietic stem/progenitor cells present in umbilical cord blood. More recently, it was reported that enucleated RBCs could be abundantly produced from human embryonic stem (ES) cells. The common obstacle for application of these methods is that they require very high cost to produce sufficient number of RBCs that are applicable in the clinic. If erythroid cell lines (immortalized cell lines) able to produce transfusable RBCs ex vivo were established, they would be valuable resources. Our group developed a robust method to obtain immortalized erythroid cell lines able to produce mature RBCs. To the best of our knowledge, this was the first paper to show the feasibility of establishing immortalized erythroid progenitor cell lines able to produce enucleated RBCs ex vivo. This result strongly suggests that immortalized human erythroid progenitor cell lines able to produce mature RBCs ex vivo can also be established. PMID:21785608

  7. Stimulation of calcium-sodium exchange in dog red blood cells by hemolysis and resealing.

    PubMed

    Parker, J C

    1988-09-01

    Osmotic hemolysis and resealing greatly increase calcium influx in dog red blood cells. The resealed ghosts show a saturable calcium entry pathway with complex kinetics. As expected for a calcium-sodium exchanger, calcium uptake is stimulated by internal sodium and inhibited by external sodium. Compared to fresh, intact red cells the resealed ghost calcium-sodium exchanger is less responsive to quinidine and to alterations in medium tonicity. The differences in calcium uptake rate among cells from different donors are minimized in the ghost preparation. There are several ways to stimulate sodium-dependent calcium movements in these cells, of which hemolysis-resealing is the most potent. The results of these and previous studies suggest that dog red blood cells have a latent capacity for calcium-sodium exchange. PMID:3415988

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

    NASA Astrophysics Data System (ADS)

    Khan, Manas; Mohanty, Samarendra K.; Sood, A. K.

    2005-11-01

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

  9. Packed Bed Reactor Experiment

    NASA Video Gallery

    The purpose of the Packed Bed Reactor Experiment in low gravity is to determine how a mixture of gas and liquid flows through a packed bed in reduced gravity. A packed bed consists of a metal pipe ...

  10. Competitive migration behaviors of multiple ions and their impacts on ion-exchange resin packed microbial desalination cell.

    PubMed

    Zuo, Kuichang; Yuan, Lulu; Wei, Jincheng; Liang, Peng; Huang, Xia

    2013-10-01

    Mixed ion-exchange resins packed microbial desalination cell (R-MDC) could stabilize the internal resistance, however, the impacts of multiple ions on R-MDC performance was unclear. This study investigated the desalination performance, multiple ions migration behaviors and their impacts on R-MDCs fed with salt solution containing multiple anions and cations. Results showed that R-MDC removed multiple anions better than multiple cations with desalination efficiency of 99% (effluent conductivity <0.05 ms/cm) at hydraulic retention time of 50 h. Competitive migration order was SO4(2-)>NO3(-)>Cl(-) for anions and Ca(2+)≈Mg(2+)>NH4(+)>Na(+) for cations, jointly affected by both their molar conductivity and exchange selectivity on resins. After long-term operation, the existence of higher concentration Ca(2+) and Mg(2+) caused the electric conductivity of mixed resins decrease and scaling on the surface of cation-exchange membrane adjoined with cathode chamber, suggesting that R-MDC would be more suitable for desalination of water with lower hardness.

  11. Microscale packed bed reactor for controlled hydrogen peroxide decomposition as a fuel cell oxidant aboard unmanned undersea vehicles

    NASA Astrophysics Data System (ADS)

    Lennon, E.; Burke, A. A.; Ocampo, M.; Besser, R. S.

    The multiphase catalytic decomposition of hydrogen peroxide into water and oxygen is notoriously susceptible to thermal runaway (heat of reaction: -98 kJ mol -1). The high surface area to volume ratio (S/ V) in a microscale packed bed (MPB) reactor (radius 0.5 mm) was investigated for reducing the risk of thermal runaway during hydrogen peroxide decomposition to oxygen intended as a fuel cell oxidant aboard an unmanned undersea vehicle (UUV). A microscale reactor channel with a S/ V of ∼2 × 10 3 m 2 m -3 simulated under convective cooling generated a significant heat rise (T rise ∼ 100 K), whereas a microreactor with a higher S/ V (∼200 × 10 3 m 2 m -3) achieved thermal control (T rise < 10 K) over the simulated reaction zone. Although thermal management was successfully accomplished using the higher S/ V, experimental conversions of hydrogen peroxide to oxygen (5-18%) measured from the outlet were lower than simulated conversions (38-63%). Simulation assumptions, such as homogeneously dispersed flow and perfect catalyst interaction among other factors, contributed to the discrepancies between the simulated and experimental degrees of peroxide conversion to oxygen. Even though thermal control of the MPB was achieved, this work indicates that mass transfer limitations are a factor in the MPB reactor during a multiphase reaction, like decomposition of hydrogen peroxide to oxygen and water, and suggests means to overcome them even on the microscale level.

  12. Immunospecific red cell binding of iodine /sup 125/-labeled immunoglobulin G erythrocyte autoantibodies

    SciTech Connect

    Masouredis, S.P.; Branks, M.J.; Garratty, G.; Victoria, E.J.

    1987-09-01

    The primary interaction of autoantibodies with red cells has been studied by using labeled autoantibodies. Immunoglobulin G red cell autoantibodies obtained from IgG antiglobulin-positive normal blood donors were labeled with radioactive iodine and compared with alloanti-D with respect to their properties and binding behavior. Iodine /sup 125/-labeled IgG autoantibody migrated as a single homogeneous peak with the same relative mobility as human IgG on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The isoelectric focusing pattern of labeled autoantibodies varied from donor to donor but was similar to that of alloanti-D, consisting of multiple IgG populations with isoelectric points in the neutral to alkaline range. /sup 125/I-autoantibody bound to all human red cells of common Rh phenotypes. Evidence for immunospecific antibody binding of the labeled autoantibody was based on variation in equilibrium binding to nonhuman and human red cells of common and rare phenotypes, enhanced binding after red cell protease modification, antiglobulin reactivity of cell-bound IgG comparable to that of cell-bound anti-D, and saturation binding in autoantibody excess. Scatchard analysis of two /sup 125/I-autoantibody preparations yielded site numbers of 41,500 and 53,300 with equilibrium constants of 3.7 and 2.1 X 10(8) L X mol-1. Dog, rabbit, rhesus monkey, and baboon red cells were antigen(s) negative by quantitative adsorption studies adsorbing less than 3% of the labeled autoantibody. Reduced ability of rare human D--red blood cells to adsorb the autoantibody and identification of donor autoantibodies that bind to Rh null red blood cells indicated that eluates contained multiple antibody populations of complex specificities in contrast to anti-D, which consists of a monospecific antibody population. Another difference is that less than 70% of the autoantibody IgG was adsorbed by maximum binding red blood cells as compared with greater than 85% for alloanti-D.

  13. Relationship between red cell distribution width and early renal injury in patients with gestational diabetes mellitus.

    PubMed

    Cheng, Dong; Zhao, Jiangtao; Jian, Liguo; Ding, Tongbin; Liu, Shichao

    2016-09-01

    Previous studies found that red cell distribution width was related to adverse cardiovascular events. However, few studies reported the relationship between red cell distribution width and early-stage renal injury in pregnant women with gestational diabetes mellitus. Using a cross-sectional design, 334 pregnant women with gestational diabetes mellitus were enrolled according to the criterion of inclusion and exclusion. Demographic and clinical examination data were collected. Depended on the urine albumin, study population were divided into case group (n = 118) and control group (n = 216). Compared with control group, the case group tend to be higher red cell distribution width level (13.6 ± 0.9 vs.12.5 ± 0.6, p < 0.001). The red cell distribution width was positively associated with albuminuria creatinine ratio (r = 0.567, p < 0.001). Multiple logistic regressions showed that red cell distribution width was still associated with early-stage renal injury after adjusting for many other potential cofounders. Compared with the first quartile, the risk ratio of the second, the third and the fourth quartile were 1.38 (95%CI: 1.06-1.80), 1.57 (95%CI: 1.21-2.97), 2.71 (95%CI: 2.08-3.54), respectively. Besides, systolic blood pressure, estimated glomerular filtration rate, uric acid and blood urea nitrogen were also significantly associated with renal injury in gestational diabetes mellitus patients. The elevated red cell distribution width level might be a predictor of early-stage renal injury in pregnant women with gestational diabetes mellitus. As an easy and routine examination index, red cell distribution width may provide better clinical guidance when combined with other important indices.

  14. Red cell parameters in infant and children from the Arabian Peninsula

    PubMed Central

    Mekaini, Lolowa A Al; Denic, Srdjan; Jabri, Omar N Al; Narchi, Hassib; Souid, Abdul-Kader; Al-Hammadi, Suleiman

    2015-01-01

    α+-Thalassemia trait and iron deficiency anemia are frequent causes of microcytosis and a common diagnostic challenge in Arabian children. In this study, their prevalences and effects on the red cell parameters were evaluated in 28,457 children aged one day to 6 years. α+-Thalassemia trait was considered to be present when mean cell volume (MCV) was <94 fL at birth and iron deficiency anemia when red cell distribution width (RDW) was >14.5%. The prevalence of α+-thalassemia trait was 15.7% (502/3,191), which was similar to previously reported values for adults (9-14%). Iron deficiency anemia peaked at 7 months (53%) and then declined at a rate of 8% per year. The nadirs of red blood cell count (RBC) and hemoglobin concentration (Hb) occurred at two months of age (physiological anemia). Subsequently, Hb increased at a rate similar to that of MCV, demonstrating the two processes are coupled. The third percentile MCV in children older than 3 months was ≤64 fL, which was significantly lower than that in European children. The third percentile Hb, on the other hand, was similar to that in European children. Thus, α+-thalassemia trait and iron deficiency anemia are exceptionally frequent in Arabian children and their red cell indices are considerably different from European-based norms. Careful interpretation of red cell parameters is required for the evaluation of microcytic anemia in Arabian children. PMID:27069759

  15. Neocytolysis on descent from altitude: a newly recognized mechanism for the control of red cell mass

    NASA Technical Reports Server (NTRS)

    Rice, L.; Ruiz, W.; Driscoll, T.; Whitley, C. E.; Tapia, R.; Hachey, D. L.; Gonzales, G. F.; Alfrey, C. P.

    2001-01-01

    BACKGROUND: Studies of space-flight anemia have uncovered a physiologic process, neocytolysis, by which young red blood cells are selectively hemolyzed, allowing rapid adaptation when red cell mass is excessive for a new environment. OBJECTIVES: 1) To confirm that neocytolysis occurs in another situation of acute plethora-when high-altitude dwellers with polycythemia descend to sea level; and 2) to clarify the role of erythropoietin suppression. DESIGN: Prospective observational and interventional study. SETTING: Cerro de Pasco (4380 m) and Lima (sea level), Peru. PARTICIPANTS: Nine volunteers with polycythemia. INTERVENTIONS: Volunteers were transported to sea level; three received low-dose erythropoietin. MEASUREMENTS: Changes in red cell mass, hematocrit, hemoglobin concentration, reticulocyte count, ferritin level, serum erythropoietin, and enrichment of administered(13)C in heme. RESULTS: In six participants, red cell mass decreased by 7% to 10% within a few days of descent; this decrease was mirrored by a rapid increase in serum ferritin level. Reticulocyte production did not decrease, a finding that establishes a hemolytic mechanism.(13)C changes in circulating heme were consistent with hemolysis of young cells. Erythropoietin was suppressed, and administration of exogenous erythropoietin prevented the changes in red cell mass, serum ferritin level, and(13)C-heme. CONCLUSIONS: Neocytolysis and the role of erythropoietin are confirmed in persons with polycythemia who descend from high altitude. This may have implications that extend beyond space and altitude medicine to renal disease and other situations of erythropoietin suppression, hemolysis, and polycythemia.

  16. From Red Cells to Skiing to a New Concept for a Train

    NASA Astrophysics Data System (ADS)

    Weinbaum, Sheldon

    2003-11-01

    Although a red cell differs in size by 15 orders of magnitude from a human skier there is a remarkable dynamic similarity between a red gliding on the 0.4 nm thick endothelial surface matrix (glycocalyx) that lines our capillaries and a human skiing on fresh snow powder. We shall first show that in both cases one can generate lift forces that are 3 to 4 orders of magnitude greater than ordinary lubrication theory, but the red cell is a far more efficient skier since it does not dissipate its excess pressure at its lateral edges. The glycocalyx also exhibits several other extraordinary properties. It's fibers serve as an exquisitely designed mechanotranducer that can transmit fluid shearing stresses at its edge to the cortical cytoskeleton of the endothelial cell in initiating intracellular signalling. However, their resistance to buckling during red cell arrest is negligible compared to the fluid draining pressure. Our model suggests that the latter is the secret to why even slow moving red cells can move through our capillaries with miniscule friction from the solid phase. Finally, the small elastic restoring force of the fibers allows rapid restoration of the layer after the cell has passed. These basic concepts are used to design a new kind of train that we have called the "goose down express" whose cars ride on a track whose properties mimic the endothelial surface layer. Weinbaum et al. (2003) PNAS vol. 100, pp. 7988-7995.

  17. The evolution of pretransfusion testing: from agglutination to solid-phase red cell adherence tests.

    PubMed

    Plapp, F V; Sinor, L T; Rachel, J M

    1989-01-01

    Hospital transfusion services and blood centers still use manual hemagglutination tests for most of their serological procedures. Automation of hemagglutination reactions has proven to be difficult, primarily because hemagglutination lacks an objective endpoint which can be easily interpreted by inexpensive instruments. Alternatively, solid-phase red cell adherence assays for ABO cell and serum grouping, Rh typing, red cell and platelet antibody screening, red cell and platelet crossmatching, IgA deficiency screening, hepatitis B surface antigen, and HIV antibody screening have been developed. The performance of these assays compares favorably with current hemagglutination and enzyme immunoassay methods. All of these tests share a common objective endpoint of adherence or nonadherence of indicator red cells. This uniformity allows easy interpretation of results visually, spectrophotometrically, or by image analysis. The latter technique has the potential to revolutionize the reading and interpretation of all agglutination tests. Solid-phase red cell adherence tests in microplates are ideal for batch processing large numbers of specimens. However, adherence tests are not restricted to this format. Therefore, blood grouping dipsticks have been produced, which permit testing of individual blood samples even outside of the laboratory.

  18. Direct In Vivo Electrochemical Detection of Haemoglobin in Red Blood Cells

    NASA Astrophysics Data System (ADS)

    Toh, Rou Jun; Peng, Weng Kung; Han, Jongyoon; Pumera, Martin

    2014-08-01

    The electrochemical behavior of iron ion in haemoglobin provides insight to the chemical activity in the red blood cell which is important in the field of hematology. Herein, the detection of haemoglobin in human red blood cells on glassy carbon electrode (GC) was demonstrated. Red blood cells or raw blood cells was immobilized on a glassy carbon electrode surface with Nafion films employed to sandwich the layer of biological sample firmly on the electrode surface. Cyclic voltammetry (CV) analyses revealed a well-defined reduction peak for haemoglobin at about -0.30 V (vs. Ag/AgCl) at the red blood cell (GC-Nf-RBC-3Nf) and blood (GC-Nf-B-3Nf) film modified GCE in a pH 3.5 phosphate buffer solution. We further demonstrated that the complex biological conditions of a human red blood cell displayed no interference with the detection of haemoglobin. Such findings shall have an implication on the possibilities of studying the electrochemical behaviour of haemoglobin directly from human blood, for various scientific and clinical purposes.

  19. A Review of RedOx Cycling of Solid Oxide Fuel Cells Anode

    PubMed Central

    Faes, Antonin; Hessler-Wyser, Aïcha; Zryd, Amédée; Van Herle, Jan

    2012-01-01

    Solid oxide fuel cells are able to convert fuels, including hydrocarbons, to electricity with an unbeatable efficiency even for small systems. One of the main limitations for long-term utilization is the reduction-oxidation cycling (RedOx cycles) of the nickel-based anodes. This paper will review the effects and parameters influencing RedOx cycles of the Ni-ceramic anode. Second, solutions for RedOx instability are reviewed in the patent and open scientific literature. The solutions are described from the point of view of the system, stack design, cell design, new materials and microstructure optimization. Finally, a brief synthesis on RedOx cycling of Ni-based anode supports for standard and optimized microstructures is depicted. PMID:24958298

  20. Morphological and molecular analysis calls for a reappraisal of the red rain cells of Kerala.

    PubMed

    Gangappa, Rajkumar; Burchell, Mark J; Hogg, Stuart I

    2014-02-01

    Early studies on the coloured particles that fell as red rain over southern India identified them as unicellular eukaryotes such as members of the red algae or fungi; however, the results of the present investigation are not consistent with this designation. Using transmission electron microscopy, we have demonstrated significant differences in the ultrastructure when compared with representative species from these other groups. Most notably, the red rain cells show no evidence of typical eukaryotic internal structures such as mitochondria or endoplasmic reticulum. Furthermore, comparisons based on elemental composition using energy-dispersive X-ray analysis, as well as Raman spectral signatures demonstrate significant dissimilarities in their molecular composition. The identity and origins of the red rain cells remain an enigma; however, our findings are more consistent with an unidentified prokaryote, and thus suggest that previous attempts at their identification should be reappraised.

  1. Establishment of Immortalized Human Erythroid Progenitor Cell Lines Able to Produce Enucleated Red Blood Cells

    PubMed Central

    Kurita, Ryo; Suda, Noriko; Sudo, Kazuhiro; Miharada, Kenichi; Hiroyama, Takashi; Miyoshi, Hiroyuki; Tani, Kenzaburo; Nakamura, Yukio

    2013-01-01

    Transfusion of red blood cells (RBCs) is a standard and indispensable therapy in current clinical practice. In vitro production of RBCs offers a potential means to overcome a shortage of transfusable RBCs in some clinical situations and also to provide a source of cells free from possible infection or contamination by microorganisms. Thus, in vitro production of RBCs may become a standard procedure in the future. We previously reported the successful establishment of immortalized mouse erythroid progenitor cell lines that were able to produce mature RBCs very efficiently. Here, we have developed a reliable protocol for establishing immortalized human erythroid progenitor cell lines that are able to produce enucleated RBCs. These immortalized cell lines produce functional hemoglobin and express erythroid-specific markers, and these markers are upregulated following induction of differentiation in vitro. Most importantly, these immortalized cell lines all produce enucleated RBCs after induction of differentiation in vitro, although the efficiency of producing enucleated RBCs remains to be improved further. To the best of our knowledge, this is the first demonstration of the feasibility of using immortalized human erythroid progenitor cell lines as an ex vivo source for production of enucleated RBCs. PMID:23533656

  2. Red Blood Cell Deformation Under Shear Flow: The Effect of Changing Cell Properties

    NASA Astrophysics Data System (ADS)

    Forsyth, Alison M.; Wan, Jiandi; Ristenpart, William D.; Stone, Howard A.

    2008-11-01

    The deformability of red blood cells plays a major role in the pathology of several diseases, including malaria, sickle cell anemia and spherocytosis. Moreover, deformations are believed to trigger the release of adenosine triphosphate, which helps regulate vascular tone and is consequently an important factor in various vascular diseases. Here we investigate single-cell viscoelastic responses to increased shear stress in poly(dimethylsiloxane) channels with a single constriction 2-4 times larger than a typical erythrocyte. These channels mimic arteriole-sized vessels, and have the advantage that the cell membrane is not in contact with the channel walls which have vastly different mechanical and material properties than living tissue. High-speed video and image analysis were used to quantify the trajectories and deformations of cells exposed to varied doses of diamide, a chemical known to ``rigidify'' erythrocytes. Our results show that (i) deformation is proportional to shear rate and (ii) the deformability of diamide-treated cells is greater than that of untreated cells. The latter is an unforeseen result because micropipette aspiration experiments have shown the opposite. We expect that the experimental procedure described here will be useful for characterizing the effect of different therapeutic agents on cellular deformability.

  3. Red blood cells protect endothelial cells against H/sub 2/O/sub 2/-mediated but not hyperoxia-induced damage

    SciTech Connect

    Tsan, M.F.; White, J.E.

    1988-07-01

    We studied the effect of intact red blood cells on the exogenous H/sub 2/O/sub 2/-mediated damage as well as on the hyperoxia-induced injury of cultured endothelial cells. Red blood cells protected endothelial cells against H/sub 2/O/sub 2/-mediated injury efficiently, but had no effect on the hyperoxia-induced damage. Failure of red blood cells to protect endothelial cells against hyperoxia-induced injury was not due to hemolysis. Furthermore, hyperoxia-exposed red blood cells were still capable of protecting endothelial cells against H/sub 2/O/sub 2/-mediated damage.

  4. Evaluation of integrated anaerobic/aerobic fixed-bed sequencing batch biofilm reactor for decolorization and biodegradation of azo dye acid red 18: comparison of using two types of packing media.

    PubMed

    Hosseini Koupaie, E; Alavi Moghaddam, M R; Hashemi, S H

    2013-01-01

    Two integrated anaerobic/aerobic fixed-bed sequencing batch biofilm reactor (FB-SBBR) were operated to evaluate decolorization and biodegradation of azo dye Acid Red 18 (AR18). Volcanic pumice stones and a type of plastic media made of polyethylene were used as packing media in FB-SBBR1 and FB-SBBR2, respectively. Decolorization of AR18 in both reactors followed first-order kinetic with respect to dye concentration. More than 63.7% and 71.3% of anaerobically formed 1-naphthylamine-4-sulfonate (1N-4S), as one of the main sulfonated aromatic constituents of AR18 was removed during the aerobic reaction phase in FB-SBBR1 and FB-SBBR2, respectively. Based on statistical analysis, performance of FB-SBBR2 in terms of COD removal as well as biodegradation of 1N-4S was significantly higher than that of FB-SBBR1. Spherical and rod shaped bacteria were the dominant species of bacteria in the biofilm grown on the pumice stones surfaces, while, the biofilm grown on surfaces of the polyethylene media had a fluffy structure.

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

    DOEpatents

    Bitensky, M.W.; Yoshida, Tatsuro

    1998-08-04

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

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

    DOEpatents

    Bitensky, Mark W.; Yoshida, Tatsuro

    1998-01-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2009-11-01

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

  8. Export of cyclic AMP by avian red cells and inhibition by prostaglandin A/sub 1/

    SciTech Connect

    Heasley, L.E.

    1985-01-01

    The mechanism by which PGA/sub 1/ inhibits cAMP export by avian red cells was studied, to provide details on the molecular mechanism of a prostaglandin action and on the process of cAMP export itself. The interaction of PGA/sub 1/ with pigeon red cells is a multi-step process of uptake, metabolism and secretion. (/sup 3/H)PGA rapidly enters red cells and is promptly metabolized (V/sub max/ greater than or equal to 1 nmol/min/10/sup 7/ cells) to a compound (5) that remains in the aqueous layer after ethyl acetate extraction. Chromatographic analyses, amino acid content and fast atom bombardment mass spectrometry reveal that the polar metabolite is conjugated with glutathione (PGA/sub 1/-GSH) at C-11 via a thioether bond and is largely (80%) reduced to the C-9 hydroxyl derivative.

  9. Non-tuberculous Mycobacteriosis with T-cell Lymphoma in a Red Panda (Ailurus fulgens).

    PubMed

    Fuke, N; Hirai, T; Makimura, N; Goto, Y; Habibi, W A; Ito, S; Trang, N T; Koshino, K; Takeda, M; Yamaguchi, R

    2016-01-01

    A 9-year-old male red panda (Ailurus fulgens) became emaciated and died. Necropsy examination revealed systemic lymphadenomegaly. The liver, lungs and left kidney contained multifocal yellow nodules. Microscopical examination revealed granulomatous inflammation in the liver, lungs, kidney, spleen and lymph nodes, with numerous acid-fast bacilli. Sequencing of genetic material isolated from the tissues classified the pathogen as Mycobacterium gastri. Lymphoma was found in the liver, lungs, kidney and lymph nodes. The neoplastic cells were strongly labelled for expression of CD3, Ki67 and proliferating cell nuclear antigen by immunohistochemistry. This is the first report of M. gastri infection with T-cell lymphoma in a red panda.

  10. Application of 30-MHz acoustic scattering to the study of human red blood cells

    SciTech Connect

    Roos, M.S.; Apfel, R.E.; Wardlaw, S.C.

    1988-04-01

    A technique for simultaneously measuring the scattering amplitude of individual particles at two angles is applied to human red blood cells. Using a Rayleigh scattering model, the density and compressibility of the cells may be determined given a priori knowledge of their volume. A calibration method relying on measurements of the bulk properties of particle suspensions is described. Red cell properties in hypotonic and hypertonic hosts are compared with a homogeneous mixture model, and a linear relation between hemoglobin content and scattering amplitude at a 90 deg scattering angle is established.

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

    PubMed

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

    1995-06-01

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

  12. Erythropoietin withdrawal alters interactions between young red blood cells, splenic endothelial cells, and macrophages: an in vitro model of neocytolysis

    NASA Technical Reports Server (NTRS)

    Trial, J.; Rice, L.; Alfrey, C. P.

    2001-01-01

    BACKGROUND: We have described the rapid destruction of young red blood cells (neocytolysis) in astronauts adapting to microgravity, in polycythemic high altitude dwellers who descend to sea level, and in patients with kidney disorders. This destruction results from a decrease in erythropoietin (EPO) production. We hypothesized that such EPO withdrawal could trigger physiological changes in cells other than red cell precursors and possibly lead to the uptake and destruction of young red cells by altering endothelial cell-macrophage interactions, most likely occurring in the spleen. METHODS: We identified EPO receptors on human splenic endothelial cells (HSEC) and investigated the responses of these cells to EPO withdrawal. RESULTS: A monolayer of HSEC, unlike human endothelial cells from aorta, glomerulus, or umbilical vein, demonstrated an increase in permeability upon EPO withdrawal that was accompanied by unique morphological changes. When HSEC were cultured with monocyte-derived macrophages (but not when either cell type was cultured alone), EPO withdrawal induced an increased ingestion of young red cells by macrophages when compared with the constant presence or absence of EPO. CONCLUSIONS: HSEC may represent a unique cell type that is able to respond to EPO withdrawal by increasing permeability and interacting with phagocytic macrophages, which leads to neocytolysis.

  13. Infra-red photoresponse of mesoscopic NiO-based solar cells sensitized with PbS quantum dot

    PubMed Central

    Raissi, Mahfoudh; Pellegrin, Yann; Jobic, Stéphane; Boujtita, Mohammed; Odobel, Fabrice

    2016-01-01

    Sensitized NiO based photocathode is a new field of investigation with increasing scientific interest in relation with the development of tandem dye-sensitized solar cells (photovoltaic) and dye-sensitized photoelectrosynthetic cells (solar fuel). We demonstrate herein that PbS quantum dots (QDs) represent promising inorganic sensitizers for NiO-based quantum dot-sensitized solar cells (QDSSCs). The solar cell sensitized with PbS quantum dot exhibits significantly higher photoconversion efficiency than solar cells sensitized with a classical and efficient molecular sensitizer (P1 dye = 4-(Bis-{4-[5-(2,2-dicyano-vinyl)-thiophene-2-yl]-phenyl}-amino)-benzoic acid). Furthermore, the system features an IPCE (Incident Photon-to-Current Efficiency) spectrum that spreads into the infra-red region, reaching operating wavelengths of 950 nm. The QDSSC photoelectrochemical device works with the complexes tris(4,4′-ditert-butyl-2,2′-bipyridine)cobalt(III/II) redox mediators, underscoring the formation of a long-lived charge-separated state. The electrochemical impedance spectrocopy measurements are consistent with a high packing of the QDs upon the NiO surface, the high density of which limits the access of the electrolyte and results in favorable light absorption cross-sections and a significant hole lifetime. These notable results highlight the potential of NiO-based photocathodes sensitized with quantum dots for accessing and exploiting the low-energy part of the solar spectrum in photovoltaic and photocatalysis applications. PMID:27125454

  14. Infra-red photoresponse of mesoscopic NiO-based solar cells sensitized with PbS quantum dot

    NASA Astrophysics Data System (ADS)

    Raissi, Mahfoudh; Pellegrin, Yann; Jobic, Stéphane; Boujtita, Mohammed; Odobel, Fabrice

    2016-04-01

    Sensitized NiO based photocathode is a new field of investigation with increasing scientific interest in relation with the development of tandem dye-sensitized solar cells (photovoltaic) and dye-sensitized photoelectrosynthetic cells (solar fuel). We demonstrate herein that PbS quantum dots (QDs) represent promising inorganic sensitizers for NiO-based quantum dot-sensitized solar cells (QDSSCs). The solar cell sensitized with PbS quantum dot exhibits significantly higher photoconversion efficiency than solar cells sensitized with a classical and efficient molecular sensitizer (P1 dye = 4-(Bis-{4-[5-(2,2-dicyano-vinyl)-thiophene-2-yl]-phenyl}-amino)-benzoic acid). Furthermore, the system features an IPCE (Incident Photon-to-Current Efficiency) spectrum that spreads into the infra-red region, reaching operating wavelengths of 950 nm. The QDSSC photoelectrochemical device works with the complexes tris(4,4‧-ditert-butyl-2,2‧-bipyridine)cobalt(III/II) redox mediators, underscoring the formation of a long-lived charge-separated state. The electrochemical impedance spectrocopy measurements are consistent with a high packing of the QDs upon the NiO surface, the high density of which limits the access of the electrolyte and results in favorable light absorption cross-sections and a significant hole lifetime. These notable results highlight the potential of NiO-based photocathodes sensitized with quantum dots for accessing and exploiting the low-energy part of the solar spectrum in photovoltaic and photocatalysis applications.

  15. Infra-red photoresponse of mesoscopic NiO-based solar cells sensitized with PbS quantum dot.

    PubMed

    Raissi, Mahfoudh; Pellegrin, Yann; Jobic, Stéphane; Boujtita, Mohammed; Odobel, Fabrice

    2016-01-01

    Sensitized NiO based photocathode is a new field of investigation with increasing scientific interest in relation with the development of tandem dye-sensitized solar cells (photovoltaic) and dye-sensitized photoelectrosynthetic cells (solar fuel). We demonstrate herein that PbS quantum dots (QDs) represent promising inorganic sensitizers for NiO-based quantum dot-sensitized solar cells (QDSSCs). The solar cell sensitized with PbS quantum dot exhibits significantly higher photoconversion efficiency than solar cells sensitized with a classical and efficient molecular sensitizer (P1 dye = 4-(Bis-{4-[5-(2,2-dicyano-vinyl)-thiophene-2-yl]-phenyl}-amino)-benzoic acid). Furthermore, the system features an IPCE (Incident Photon-to-Current Efficiency) spectrum that spreads into the infra-red region, reaching operating wavelengths of 950 nm. The QDSSC photoelectrochemical device works with the complexes tris(4,4'-ditert-butyl-2,2'-bipyridine)cobalt(III/II) redox mediators, underscoring the formation of a long-lived charge-separated state. The electrochemical impedance spectrocopy measurements are consistent with a high packing of the QDs upon the NiO surface, the high density of which limits the access of the electrolyte and results in favorable light absorption cross-sections and a significant hole lifetime. These notable results highlight the potential of NiO-based photocathodes sensitized with quantum dots for accessing and exploiting the low-energy part of the solar spectrum in photovoltaic and photocatalysis applications. PMID:27125454

  16. Infra-red photoresponse of mesoscopic NiO-based solar cells sensitized with PbS quantum dot.

    PubMed

    Raissi, Mahfoudh; Pellegrin, Yann; Jobic, Stéphane; Boujtita, Mohammed; Odobel, Fabrice

    2016-04-29

    Sensitized NiO based photocathode is a new field of investigation with increasing scientific interest in relation with the development of tandem dye-sensitized solar cells (photovoltaic) and dye-sensitized photoelectrosynthetic cells (solar fuel). We demonstrate herein that PbS quantum dots (QDs) represent promising inorganic sensitizers for NiO-based quantum dot-sensitized solar cells (QDSSCs). The solar cell sensitized with PbS quantum dot exhibits significantly higher photoconversion efficiency than solar cells sensitized with a classical and efficient molecular sensitizer (P1 dye = 4-(Bis-{4-[5-(2,2-dicyano-vinyl)-thiophene-2-yl]-phenyl}-amino)-benzoic acid). Furthermore, the system features an IPCE (Incident Photon-to-Current Efficiency) spectrum that spreads into the infra-red region, reaching operating wavelengths of 950 nm. The QDSSC photoelectrochemical device works with the complexes tris(4,4'-ditert-butyl-2,2'-bipyridine)cobalt(III/II) redox mediators, underscoring the formation of a long-lived charge-separated state. The electrochemical impedance spectrocopy measurements are consistent with a high packing of the QDs upon the NiO surface, the high density of which limits the access of the electrolyte and results in favorable light absorption cross-sections and a significant hole lifetime. These notable results highlight the potential of NiO-based photocathodes sensitized with quantum dots for accessing and exploiting the low-energy part of the solar spectrum in photovoltaic and photocatalysis applications.

  17. Human red blood cell aging: correlative changes in surface charge and cell properties.

    PubMed

    Huang, Yao-Xiong; Wu, Zheng-Jie; Mehrishi, Jitendra; Huang, Bao-Tian; Chen, Xing-Yao; Zheng, Xin-Jing; Liu, Wen-Jing; Luo, Man

    2011-12-01

    Red blood cells (RBCs) during microcirculation, aging and storage, lose N-acetylneuraminic acid (NANA) and other biomaterials thereby altering cell structures, some properties and functions. Such cell damage very likely underlies the serious adverse effects of blood transfusion. However, a controversy has remained since 1961-1977 as to whether with aging, the RBCs, suffering loss of NANA, do have a decreased charge density. Any correlation between the changes in the cell properties with cell aging is also not clear. Therefore, to remove the ambiguity and uncertainty, we carried out multiparameteric studies on Percoll fractions of blood of 38 volunteers (lightest-young-Y-RBCs, densest-old-O-RBCs, two middle fractions).We found that there were striking differences between the properties of Y-RBCs and O-RBCs. The ζ-potential of Y-RBCs decreased gradually with aging. Studies in parallel on RBC fractions incubated with both positively charged quantum dots and Sambucus Nigra-fluorescein isothiocyanate (FITC) along with their ζ-potentials provide for the first time direct visual evidence about the lesser amount of charge density and NANA on O-RBCs, and a collinear decrease in their respective ζ-potentials. Close correlation was found between the surface charge on an aging RBC and its structure and functions, from the cell morphology, the membrane deformability to the intracellular Hb structure and oxidation ability. This quantitative approach not only clarifies the picture but also has implications in biology and medicine.

  18. Mechanical differences of sickle cell trait (SCT) and normal red blood cells.

    PubMed

    Zheng, Yi; Cachia, Mark A; Ge, Ji; Xu, Zhensong; Wang, Chen; Sun, Yu

    2015-08-01

    Sickle cell trait (SCT) is a condition in which an individual inherits one sickle hemoglobin gene (HbS) and one normal beta hemoglobin gene (HbA). It has been hypothesized that under extreme physical stress, the compromised mechanical properties of the red blood cells (RBCs) may be the underlying mechanism of clinical complications of sickle cell trait individuals. However, whether sickle cell trait (SCT) should be treated as physiologically normal remains controversial. In this work, the mechanical properties (i.e., shear modulus and viscosity) of individual RBCs were quantified using a microsystem capable of precisely controlling the oxygen level of RBCs' microenvironment. Individual RBCs were deformed under shear stress. After the release of shear stress, the dynamic cell recovery process was captured and analyzed to extract the mechanical properties of single RBCs. The results demonstrate that RBCs from sickle cell trait individuals are inherently stiffer and more viscous than normal RBCs from healthy donors, but oxygen level variations do not alter their mechanical properties or morphology.

  19. Estimation of transfused red cell survival using an enzyme-linked antiglobulin test

    SciTech Connect

    Kickler, T.S.; Smith, B.; Bell, W.; Drew, H.; Baldwin, M.; Ness, P.M.

    1985-09-01

    An enzyme-linked antiglobulin test (ELAT) method was developed to estimate survival of transfused red cells. This procedure is based on a principle analogous to that of the Ashby technique were antigenically distinct red cells are transfused and their survival studied. The authors compared the ELAT survival to the V Chromium method (V Cr) in four patients. Three patients with hypoproliferative anemias showed T 1/2 by ELAT of 17.5, 18, and 17 days versus 18.5, 20, and 19 days by the V Cr method. A fourth patient with traumatic cardiac hemolysis had two studies performed. In this case, the ELAT showed a T 1/2 of 10 and 8.1 days while V Cr T 1/2 values were 11 and 10.5 days. The ELAT method for measuring red cell survival yielded data which agreed closely with the results of the V Cr method. Although V Cr is the accepted method for red cell survival, the ELAT method can be used to estimate transfused red cell survival.

  20. The red cell mass-arterial oxygen relationship in normal man

    PubMed Central

    Weil, John V.; Jamieson, Gail; Brown, Donald W.; Grover, Robert F.

    1968-01-01

    The normal relationship between red cell mass measured, with 51chromium-labeled red cells, and arterial oxygen saturation (SaO2) over the range from 97.3 to 83.4% was examined by studying 73 normal men residing at sea level and altitudes of 1600 and 3100 m. A simple, linear relationship between SaO2 and red cell mass was found over the entire range (r = - 0.7524, P < 0.001). In contrast, a correlation between red cell mass and arterial O2 tension was found only over the lower half of the range of O2 tensions where SaO2 was also decreased (r = - 0.7731, P < 0.005). This suggested that O2 saturation rather than tension is the more important determinant of the erythropoietic response to chronic hypoxia. If this response is regulated by tissue O2 tension, then it will be influenced by O2 transport, which, in turn, is a function of blood flow and arterial O2 content, and hence SaO2. In nine patients with chronic obstructive airway disease the relationship between red cell mass and SaO2 was also determined and was found to be steeper than in the normal subjects (P < 0.05). Images PMID:5658592

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

    PubMed

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

    2015-01-01

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

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

    PubMed Central

    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. PMID:26557672

  3. A cell line derived from the red flour beetle Tribolium castaneum (Coleoptera: Tenebrionidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The red flour beetle, Tribolium castaneum, is a model organism for agricultural and medical research and its complete genome is sequenced. We established a continuously replicating T. castaneum cell line to complement existing physiological, genetic and genomic research tools. We set up trial cell ...

  4. Role of Calcium in Phosphatidylserine Externalisation in Red Blood Cells from Sickle Cell Patients

    PubMed Central

    Weiss, Erwin; Rees, David Charles; Gibson, John Stanley

    2011-01-01

    Phosphatidylserine exposure occurs in red blood cells (RBCs) from sickle cell disease (SCD) patients and is increased by deoxygenation. The mechanisms responsible remain unclear. RBCs from SCD patients also have elevated cation permeability, and, in particular, a deoxygenation-induced cation conductance which mediates Ca2+ entry, providing an obvious link with phosphatidylserine exposure. The role of Ca2+ was investigated using FITC-labelled annexin. Results confirmed high phosphatidylserine exposure in RBCs from SCD patients increasing upon deoxygenation. When deoxygenated, phosphatidylserine exposure was further elevated as extracellular [Ca2+] was increased. This effect was inhibited by dipyridamole, intracellular Ca2+ chelation, and Gardos channel inhibition. Phosphatidylserine exposure was reduced in high K+ saline. Ca2+ levels required to elicit phosphatidylserine exposure were in the low micromolar range. Findings are consistent with Ca2+ entry through the deoxygenation-induced pathway (Psickle), activating the Gardos channel. [Ca2+] required for phosphatidylserine scrambling are in the range achievable in vivo. PMID:21490763

  5. Rationale and Design of the Informing Fresh versus Old Red Cell Management (INFORM) Trial: An International Pragmatic Randomized Trial.

    PubMed

    Eikelboom, John W; Cook, Richard J; Barty, Rebecca; Liu, Yang; Arnold, Donald M; Crowther, Mark A; Devereaux, Philip J; Ellis, Martin; Figueroa, Priscilla; Gallus, Alex; Hirsh, Jack; Kurz, Andrea; Roxby, David; Sessler, Daniel I; Sharon, Yehudit; Sobieraj-Teague, Magdalena; Warkentin, Theodore E; Webert, Kathryn E; Heddle, Nancy M

    2016-01-01

    Although red blood cell transfusion is a potentially lifesaving intervention in severely anemic and acutely bleeding patients, some observational studies have suggested that prolonged red cell storage before transfusion is associated with harm. INFORM is a large, pragmatic, randomized controlled trial comparing the effect of the shorter storage with longer storage red blood cell transfusions on inhospital mortality in hospitalized patients who require a blood transfusion. The trial is being conducted in centers in Australia, Canada, Israel, and the United States and is expected to enroll 31497 patients. If the results of INFORM indicate that shorter storage red blood cell transfusion is associated with superior outcomes compared with standard issue red blood cell transfusion, consideration may be given to shortening blood storage times. If, in contrast, the INFORM trial provides no evidence of harm from longer storage red blood cells, clinicians and patients may be reassured that current blood inventory management strategies are appropriate.

  6. Rationale and Design of the Informing Fresh versus Old Red Cell Management (INFORM) Trial: An International Pragmatic Randomized Trial.

    PubMed

    Eikelboom, John W; Cook, Richard J; Barty, Rebecca; Liu, Yang; Arnold, Donald M; Crowther, Mark A; Devereaux, Philip J; Ellis, Martin; Figueroa, Priscilla; Gallus, Alex; Hirsh, Jack; Kurz, Andrea; Roxby, David; Sessler, Daniel I; Sharon, Yehudit; Sobieraj-Teague, Magdalena; Warkentin, Theodore E; Webert, Kathryn E; Heddle, Nancy M

    2016-01-01

    Although red blood cell transfusion is a potentially lifesaving intervention in severely anemic and acutely bleeding patients, some observational studies have suggested that prolonged red cell storage before transfusion is associated with harm. INFORM is a large, pragmatic, randomized controlled trial comparing the effect of the shorter storage with longer storage red blood cell transfusions on inhospital mortality in hospitalized patients who require a blood transfusion. The trial is being conducted in centers in Australia, Canada, Israel, and the United States and is expected to enroll 31497 patients. If the results of INFORM indicate that shorter storage red blood cell transfusion is associated with superior outcomes compared with standard issue red blood cell transfusion, consideration may be given to shortening blood storage times. If, in contrast, the INFORM trial provides no evidence of harm from longer storage red blood cells, clinicians and patients may be reassured that current blood inventory management strategies are appropriate. PMID:26651419

  7. Effects of oral powder electrolyte administration on packed cell volume, plasma chemistry parameters, and incidence of colic in horses participating in a 6-day 162-km trail ride.

    PubMed

    Walker, Wade T; Callan, Robert J; Hill, Ashley E; Tisher, Kelly B

    2014-08-01

    This study evaluated the effects of administering oral powder electrolytes on packed cell volume (PCV), plasma chemistry parameters, and incidence of colic in horses participating on a 6-day 162-km trail ride in which water was not offered ad libitum. Twenty-three horses received grain with powder electrolytes daily while 19 control horses received grain only. Horses were ridden approximately 32 km a day at a walk or trot. Packed cell volume and plasma chemistry parameters were analyzed daily. Episodes of colic were diagnosed and treated by a veterinarian unaware of treatment group allocation. Blood parameters and incidence of colic were compared between treatment groups. Electrolyte administration did not alter PCV or plasma chemistry parameters compared to controls. The incidence of colic was significantly higher in treated horses (P = 0.05). Oral powder electrolytes did not enhance hydration status or electrolyte homeostasis and may be associated with colic in horses participating on long distance trail rides similar to this model.

  8. Reduction of exposure to blood donors in preterm infants submitted to red blood cell transfusions using pediatric satellite packs

    PubMed Central

    Uezima, Cristina Lika; Barreto, Ariane Moreira; Guinsburg, Ruth; Chiba, Akemi Kuroda; Bordin, José Orlando; Barros, Melca Maria O.; dos Santos, Amélia Miyashiro N.

    2013-01-01

    OBJECTIVE: In preterm newborn infants transfused with erythrocytes stored up to 28 days, to compare the reduction of blood donor exposure in two groups of infants classified according to birth weight. METHODS: A prospective study was conducted with preterm infants with birth weight <1000g (Group 1) and 1000-1499g (Group 2), born between April, 2008 and December, 2009. Neonates submitted to exchange transfusions, emergency erythrocyte transfusion, or those who died in the first 24 hours of life were excluded. Transfusions were indicated according to the local guideline using pediatric transfusion satellite bags. Demographic and clinical data, besides number of transfusions and donors were assessed. . Logistic regression analysis was performed to determine factors associated with multiple transfusions. RESULTS: 30 and 48 neonates were included in Groups 1 and 2, respectively. The percentage of newborns with more than one erythrocyte transfusion (90 versus 11%), the median number of transfusions (3 versus 1) and the median of blood donors (2 versus 1) were higher in Group 1 (p<0.001), compared to Group 2. Among those with multiple transfusions, 14 (82%) and one (50%) presented 50% reduction in the number of blood donors, respectively in Groups 1 and 2. Factors associated with multiple transfusions were: birth weight <1000g (OR 11.91; 95%CI 2.14-66.27) and presence of arterial umbilical catheter (OR 8.59; 95%CI 1.94-38.13), adjusted for confounders. CONCLUSIONS: The efficacy of pediatrics satellites bags on blood donor reduction was higher in preterm infants with birth weight <1000g. PMID:24142309

  9. In vitro metabolism study of normal and tumor cells when exposed to red LED light

    NASA Astrophysics Data System (ADS)

    Stolbovskaya, Olga V.; Khairullin, Radik M.; Saenko, Yuri V.; Krasnikova, Ekaterina S.; Krasnikov, Aleksandr V.; Fomin, Aleksandr A.; Skaptsov, Aleksandr A.

    2016-04-01

    This work presents the results of studying the mitochondrial membrane potential, intracellular ROS, peculiarities of the cell cycle of cancer cells HCT-116 and the normal line of CHO cells when exposed to the red LED light with a wavelength range of 0.620-0.680 μm. A dose-dependent increase in mitochondrial membrane potential and intracellular ROS concentration in cancer cells HCT-116 was established. In normal CHO cell line a dose-dependent reduction of mitochondrial membrane potential and dose-dependent increase in intracellular ROS occur. It has been shown that the sensitivity of the studied cell lines to the red light depends on the stage of the cell cycle.

  10. Differential effects of temperature on three components of passive permeability to potassium in rodent red cells.

    PubMed Central

    Hall, A C; Willis, J S

    1984-01-01

    The effect of temperature on ouabain-insensitive fluxes of K+ was characterized in red cells from a non-hibernator (guinea-pig) and a hibernator (thirteen-lined ground squirrel). The residual K+ influx which remains in the presence of ouabain and bumetanide, and which is linearly dependent on [K+]o was the same in the erythrocytes of the two species at low temperature (5 degrees C). At 5 degrees C co-transport of K+ was abolished in guinea-pig red cells but was still present in ground squirrel red cells. In guinea-pig cells, ouabain-and-bumetanide-insensitive K+ flux was increased by Ca2+ at low temperatures. This flux was inhibited by quinine and selective for K+ over Na+, indicating activation of the Ca2+-sensitive K+ pathway (Gárdos channel). Ouabain-and-bumetanide-insensitive K+ permeability in red cells from the ground squirrel was insensitive to Ca2+ added to the medium at low temperature. When ground squirrel red cells were depleted of ATP or treated with A23187, Ca2+ induced a flux which was inhibitable by quinine. Hence, ground squirrel red cells possess Gárdos channels. The temperature sensitivity of the K+ channels was assessed using A23187-mediated K+ influx as a measure of Gárdos channel activation. The influence of temperature on the Ca2+-stimulated K+ fluxes under these conditions was indistinguishable between the two species. It is concluded that K+ loss through the Ca2+-sensitive K+ channel is minimal in hibernators' erythrocytes because of more efficient regulation of cytoplasmic Ca2+ during cold storage. PMID:6325676

  11. Genomewide scans of red cell indices suggest linkage on chromosome 6q23

    PubMed Central

    Iliadou, A; Evans, D M; Zhu, G; Duffy, D L; Frazer, I H; Montgomery, G W; Martin, N G

    2007-01-01

    Background The red cell indices quantify the size, number and oxygen‐carrying ability of erythrocytes. Although the genetic basis of many monogenic forms of anaemia is well understood, comparatively little is known about the genes responsible for variation in the red cell indices among healthy participants. Objective To identify quantitative trait loci (QTLs) responsible for normal variation in the red cell indices of 391 pairs of dizygotic twins who were measured longitudinally at 12, 14 and 16 years of age. Results Evidence suggesting linkage of red cell indices to haemoglobin concentration (LOD  = 3.03) and haematocrit (LOD  = 2.95) on chromosome 6q23, a region previously identified as possibly harbouring a QTL for haematocrit, was found. Evidence for linkage to several other regions of the genome, including chromosome 4q32 for red cell count and 7q for mean cell volume, was also found. In contrast, there was little evidence of linkage to the chromosomal regions containing the genes for erythropoietin (7q21) and its receptor (19p13.2), nor to the regions containing the genes for the haemoglobin α (16p13.3) and β chains (11p15.5). Conclusion Findings provide additional evidence for a QTL affecting haemoglobin and haematocrit on chromosome 6q23. In contrast, polymorphisms in the genes coding for erythropoietin, its receptor and the haemoglobin α and β chains do not appear to contribute substantially to variation in the red cell indices between healthy persons. PMID:16950815

  12. Effects of nitric oxide and its congeners on sickle red blood cell deformability

    PubMed Central

    Belanger, Andrea M.; Keggi, Christian; Kanias, Tamir; Gladwin, Mark T.; Kim-Shapiro, Daniel B.

    2015-01-01

    BACKGROUND Sickle cell disease is characterized by hemoglobin (Hb) polymerization upon deoxygenation. Polymerization causes the sickle cells to become rigid and misshapen (sickling). Red blood cell (RBC) dehydration greatly increases polymerization. Cycles of sickling and unsickling cause an influx of calcium that leads to loss of potassium via the calcium-activated Gardos channel which dehydrates the cells leading to increased polymerization. In this study effects of NO and its congeners on RBC deformability were examined, focusing on sickle red blood cells. STUDY DESIGN AND METHODS Red blood cells from patients with sickle cell disease and from non-patients were exposed to various compounds that release NO or its congeners. Intracellular calcium was increased using a calcium ionophore or cycling of oxygen tension for sickle red blood cells. Deformability was measured by laser-assisted osmotic gradient ektacytometry. RESULTS Consistent with a previous report, sodium nitroprusside (SNP) was found to protect against calcium-induced loss of deformability in normal red blood cells, but (contrary to some previous reports) no effect of any NO donors was observed when calcium influx was not induced. Importantly, in studies of deoxygenation-induced dehydration of sickle RBCs, SNP resulted in substantial improvements in deformability (p=0.036) and hydration (p=0.024). Sodium nitrite showed similar trends. SNP was shown to have no effect on calcium influx, but reduced potassium efflux. CONCLUSION These data suggest SNP and perhaps certain nitrogen oxides (like nitrite) inhibit the Gardos channel and may be able to protect sickle cells from dehydration and thereby improve outcome in the disease. PMID:25912054

  13. Getting into the flow: Red cells go on a roll, two-component vesicles swing

    NASA Astrophysics Data System (ADS)

    Viallat, Annie; Dupire, Jules; Khelloufi, Kamel; Al Halifa, Al Hair; Adhesion and Inflammation Team

    2013-11-01

    Red blood cells are soft capsules. Under shear flow, their two known motions were ``tumbling'' and ``swinging-tank treading,'' depending on cell mechanics and flow conditions. We reveal new wobbling regimes, among which the ``rolling'' regime, where red cells move as wheels on a road. We show, by coupling two video-microscopy approaches providing multi-directional cell pictures that the orientation of cells flipping into the flow is determined by the shear rate. Rolling permits to avoid energetically costly cellular deformations and is a true signature of the cytoskeleton elasticity. We highlight two transient dynamics: an intermittent regime during the ``tank-treading-to-flipping'' transition and a Frisbee-like ``spinning'' regime during the ``rolling-to-tank-treading'' transition. We find that the biconcave red cell shape is very stable under moderate shear stresses, and we interpret this result in terms of shape memory and elastic buckling. Finally, we generate lipid vesicles with a shape memory by using two lipids with different bending rigidities. These vesicles swing in shear flow similarly to red blood cells but their non-axisymmetric stress-free shape changes the periodicity of the motion and induces specific features.

  14. Leukaemia x fibroblast hybrid cells augment the antibody response to sheep red blood cells in inbred mice.

    PubMed Central

    Cohen, E P; Hagen, K

    1985-01-01

    ASL-1 x LM(TK-) hybrid cells, an established murine leukaemia x fibroblast hybrid cell line, augment the antibody response to sheep red blood cells in inbred mice, as determined by the plaque assay method. The intraperitoneal injection of viable hybrid cells or of growth medium conditioned by the cells leads to an increase both in the total number as well as the proportion of cells forming antibodies to sheep red blood cells. CSF-1, (M-CSF), is detected by radioimmunoassay in the medium conditioned by the hybrid and LM(TK-) cells, but not ASL-1 parental cells. Prior treatment of the conditioned medium with CSF-1 antiserum reduces its capacity to augment the antibody response, and its proliferative stimulus on cells from the marrow indicating that CSF-1 may be at least partly responsible for the adjuvant effect observed. The intraperitoneal implantation of diffusion chambers containing viable CSF-1 producing hybrid cells, like the cells themselves, also leads to an increase in the number of spleen cells forming antibodies to sheep red blood cells. PMID:3908292

  15. Routine Storage of Red Blood Cell Units in Additive Solution-3: a comprehensive investigation of the RBC metabolome

    PubMed Central

    D'Alessandro, Angelo; Nemkov, Travis; Kelher, Marguerite; West, Bernadette F.; Schwindt, Rani K.; Banerjee, Anirban; Moore, Ernest E; Silliman, Christopher C.; Hansen, Kirk C.

    2014-01-01

    Background In most countries, packed red blood cells (RBCs) can be stored up to 42 days before transfusion. However, observational studies have suggested that storage duration might be associated with increased morbidity and mortality. While clinical trials are underway, impaired metabolism has been documented in RBCs stored in several additive solutions. Here we hypothesize that, despite reported beneficial effects, storage in additive solution-3 (AS-3) results in metabolic impairment weeks before the end of the unit shelf-life. Study design and Methods Five leukocyte-filtered AS-3 RBC units were sampled before, during and after leukoreduction at day0, and then assayed on a weekly basis from storage day1 through day42. RBC extracts and supernatants were assayed using a UHPLC-MS metabolomics workflow. Results Blood bank storage significantly affects metabolic profiles of RBC extracts and supernatants by day14. In addition to energy and redox metabolism impairment, intra- and extracellular accumulation of amino acids was observed proportionally to storage duration, suggesting a role for glutamine and serine metabolism in aging RBCs. Conclusion Metabolomics of stored RBCs could drive the introduction of alternative additive solutions to address some of the storage-dependent metabolic lesions herein reported, thereby increasing the quality of transfused RBCs and minimizing potential links to patient morbidity. PMID:25556331

  16. Effect of thiourea on PCMBS inhibition of osmotic water transport in human red cells.

    PubMed

    Chasan, B; Lukacovic, M F; Toon, M R; Solomon, A K

    1984-11-21

    The organomercurial reagent p-chloromercuribenzene sulfonate (PCMBS) is an inhibitor of osmotic water permeability in the human red cell membrane. We have found that thiourea, when added along with PCMBS to a red cell suspension, interferes with this inhibition and at high enough concentrations prevents the inhibition from developing altogether. For a 2 mM PCMBS concentration Ki = 3 +/- 1 mM. When thiourea is added at a later time, the PCMBS inhibition, which normally takes about 20 min to develop fully, is halted and remains fixed at the value attained by that time. Thiourea also inhibits the reversal of PCMBS inhibition by a 10 mM concentration of cysteine, the half-time for reversal increasing by more than an order of magnitude when [thiourea] = 50 mM. Possible implications for the nature of the water and urea transport pathways across the red cell membrane are discussed. PMID:6093879

  17. Red cell volume with changes in plasma osmolarity during maximal exercise.

    NASA Technical Reports Server (NTRS)

    Van Beaumont, W.

    1973-01-01

    The volume of the red cell in vivo was measured during acute changes in plasma osmolarity evoked through short (6 to 8 min) maximal exercise in six male volunteer subjects. Simultaneous measurements of mean corpuscular red cell volume (MCV), hematocrit, blood hemoglobin, mean corpuscular hemoglobin concentration (MCHC), and plasma osmolarity showed that there was no change in the MCV or MCHC with a concomitant rise of nearly 6% in plasma osmolarity. Apparently, in vivo, the volume of the red cell in exercising healthy human subjects does not change measurably, in spite of significant changes in osmotic pressure of the surrounding medium. Consequently, it is not justified to correct postexercise hematocrit measurements for changes in plasma osmolarity.

  18. Hereditary disorders of red cell enzymes in the Embden-Meyerhof pathway.

    PubMed

    Miwa, S

    1983-06-01

    Recent advances about hereditary disorders of red cell enzymes in the Embden-Meyerhof glycolytic pathway and Rapoport-Leubering cycle are discussed with a stress on pyruvate kinase deficiency, because it is the most common and most intensively studied disorder among them. Broad genetic heterogeneity exists in all the known erythroenzymopathies. Recently, the primary structure of normal human red cell phosphoglycerate kinase has been determined and single amino acid substitutions of four mutant phosphoglycerate kinases have been clarified by Yoshida et al. These studies allowed analysis of structure-function relationships at the molecular level to be carried out more precisely than was previously possible. It is the consensus of the investigators working in this field that the pathogenesis in three-quarters of the congenital nonspherocytic hemolytic anemia patients remains unknown even after adequate red cell enzyme studies and isopropanol test for unstable hemoglobin have been done. This simply means that much studies remain to be worked out in this field.

  19. [Detection and characterization of anti-red cell autoantibodies in autoimmune hemolytic anemias].

    PubMed

    Kamesaki, T; Kajii, E

    1996-09-01

    Autoimmuine hemolytic anemias (AIHA) are classified into two groups of warm type and cold type according to the thermal properties of the anti-red cell autoantibody. A positive result of the antiglobulin test (DAT) confirms the presence of autoantibodies on red cells. DAT-negative AIHA are diagnosed by means of the elevation of red blood cell-associated IgG. The sera in low titer cold agglutinin disease show a low cold agglutinin titer but a high titer in the presence of bovine albumin. The antigenic specificity of warm reacting autoantibodies has been demonstrated, by using immunoblot and immunoprecipitation, such as Rh-related proteins, band 3, glycophorin A or Wrb antigen.

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

    PubMed

    Zohdi, T I; Kuypers, F A

    2006-12-22

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

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

    PubMed

    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.

  2. The effect of the unstirred layer on human red cell water permeability.

    PubMed

    Sha'afi, R I; Rich, G T; Sidel, V W; Bossert, W; Solomon, A K

    1967-05-01

    A study has been made of water entry into human red blood cells under an osmotic pressure gradient. The measurements were made using a rapid reaction stop flow apparatus, whose construction, calibration, and performance are described in detail. Red cell volume changes were determined from 90 degrees scattered light. The permeability coefficient for water entry under a relative isosmolar concentration of 1 to 1.5 was found to be 0.22 +/- 0.01 cm(4)/sec osmol, which agrees well with our previously published value. The experiments were also designed to measure the thickness of the unstirred layer around the6 red cells. This was found to be 5.5 +/- 0.8 micro under the present experimental conditions. It is concluded that our previously measured permeability coefficient for water entrance under a diffusion gradient does not require correction on account of the unstirred layer.

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

    DOEpatents

    Bitensky, Mark W.; Yoshida, Tatsuro

    1997-01-01

    Method using oxygen removal for extending the useful shelf-life of refrigerated red blood cells. A cost-effective, 4.degree. C. storage procedure that preserves red cell quality and prolongs post-transfusion in vivo survival is described. Preservation of adenosine triphosphate levels and reduction in hemolysis and in membrane vesicle production of red blood cells stored at 4.degree. C. for prolonged periods of time is achieved by removing oxygen therefrom at the time of storage; in particular, by flushing with an inert gas. Adenosine triphosphate levels of the stored red blood cells are boosted in some samples by addition of ammonium phosphate.

  4. Two-dimensional particle-in cell/Monte Carlo simulations of a packed-bed dielectric barrier discharge in air at atmospheric pressure

    NASA Astrophysics Data System (ADS)

    Zhang, Ya; Wang, Hong-yu; Jiang, Wei; Bogaerts, Annemie

    2015-08-01

    The plasma behavior in a parallel-plate dielectric barrier discharge (DBD) is simulated by a two-dimensional particle-in-cell/Monte Carlo collision model, comparing for the first time an unpacked (empty) DBD with a packed bed DBD, i.e., a DBD filled with dielectric spheres in the gas gap. The calculations are performed in air, at atmospheric pressure. The discharge is powered by a pulse with a voltage amplitude of -20 kV. When comparing the packed and unpacked DBD reactors with the same dielectric barriers, it is clear that the presence of the dielectric packing leads to a transition in discharge behavior from a combination of negative streamers and unlimited surface streamers on the bottom dielectric surface to a combination of predominant positive streamers and limited surface discharges on the dielectric surfaces of the beads and plates. Furthermore, in the packed bed DBD, the electric field is locally enhanced inside the dielectric material, near the contact points between the beads and the plates, and therefore also in the plasma between the packing beads and between a bead and the dielectric wall, leading to values of 4× {10}8 V m-1, which is much higher than the electric field in the empty DBD reactor, i.e., in the order of 2× {10}7 V m-1, thus resulting in stronger and faster development of the plasma, and also in a higher electron density. The locally enhanced electric field and the electron density in the case of a packed bed DBD are also examined and discussed for three different dielectric constants, i.e., {ɛ }r=22 (ZrO2), {ɛ }r=9 (Al2O3) and {ɛ }r=4 (SiO2). The enhanced electric field is stronger and the electron density is higher for a larger dielectric constant, because the dielectric material is more effectively polarized. These simulations are very important, because of the increasing interest in packed bed DBDs for environmental applications.

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

    PubMed

    Yang, X S; Kamino, K

    1995-01-01

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

  6. Regulation of anthocyanin biosynthesis in Arabidopsis thaliana red pap1-D cells metabolically programmed by auxins.

    PubMed

    Liu, Zhong; Shi, Ming-Zhu; Xie, De-Yu

    2014-04-01

    Red pap1-D cells of Arabidopsis thaliana have been cloned from production of anthocyanin pigmentation 1-Dominant (pap1-D) plants. The red cells are metabolically programmed to produce high levels of anthocyanins by a WD40-bHLH-MYB complex that is composed of the TTG1, TT8/GL3 and PAP1 transcription factors. Here, we report that indole 3-acetic acid (IAA), naphthaleneacetic acid (NAA) and 2,4-dichlorophenoxyacetic acid (2,4-D) regulate anthocyanin biosynthesis in these red cells. Seven concentrations (0, 0.2, 0.4, 2.2, 9, 18 and 27 μM) were tested for the three auxins. IAA and 2,4-D at 2.2-27 μM reduced anthocyanin levels. NAA at 0-0.2 μM or above 9 μM also decreased anthocyanin levels, but from 0.4 to 9 μM, it increased them. HPLC-ESI-MS analysis identified seven cyanin molecules that were produced in red pap1-D cells, and their levels were affected by auxins. The expression levels of ten genes, including six transcription factors (TTG1, EGL3, MYBL2, TT8, GL3 and PAP1) and four pathway genes (PAL1, CHS, DFR and ANS) involved in anthocyanin biosynthesis were analyzed upon various auxin treatments. The resulting data showed that 2,4-D, NAA and IAA control anthocyanin biosynthesis by regulating the expression of TT8, GL3 and PAP1 as well as genes in the anthocyanin biosynthetic pathway, such as DFR and ANS. In addition, the expression of MYBL2, PAL1 and CHS in red pap1-D and wild-type cells differentially respond to the three auxins. Our data demonstrate that the three auxins regulate anthocyanin biosynthesis in metabolically programmed red cells via altering the expression of transcription factor genes and pathway genes. PMID:24370633

  7. Isovolemic hemodilution-red cell exchange for prevention of cerebrovascular accident in sickle cell anemia: the standard operating procedure.

    PubMed

    Matevosyan, Karén; Anderson, Christina; Sarode, Ravi

    2012-01-01

    Red blood cell exchange is an accepted superior therapy to simple chronic transfusion, due to minimal risk of iron overload, for secondary prevention of cerebrovascular accidents in selected patients with sickle cell anemia. Recently, we described our experience of Isovolemic Hemodilution-Red Blood Cell Exchange (IHD-RBCx), a two-step modification of the conventional RBCx with several advantages, including cost reduction. We are describing our standard operating procedure for IHD-RBCx with COBE Spectra apheresis system to make it widely available to the apheresis centers interested in implementing this procedure.

  8. Hypoxia-induced in vivo sickling of transgenic mouse red cells.

    PubMed Central

    Rubin, E M; Witkowska, H E; Spangler, E; Curtin, P; Lubin, B H; Mohandas, N; Clift, S M

    1991-01-01

    To develop an animal model for sickle cell anemia, we have created transgenic mice that express a severe naturally occurring human sickling hemoglobin, Hb S Antilles. Due to its low solubility and oxygen affinity, Hb S Antilles has a greater propensity to cause red cell sickling than Hb S. To make transgenic animals that express a high level of Hb S Antilles, the erythroid-specific DNAse I hypersensitive site II from the human beta-globin cluster was linked independently to the human alpha 2-globin gene and to the beta S Antilles gene. Embryos were injected with both constructs simultaneously and seven transgenic mice were obtained, three of which contained both the human alpha and the human beta S Antilles transgene. After crossing the human transgenes into the mouse beta-thalassemic background a transgenic mouse line was derived in which approximately half the beta-globin chains in the murine red cells were human beta S Antilles. Deoxygenation of the transgenic red cells in vitro resulted in extensive sickling. An increase of in vivo sickling was achieved by placing these transgenic mice in a low oxygen environment. This murine model for red cell sickling should help to advance our understanding of sickle cell disease and may provide a model to test therapeutic interventions. Images PMID:1991848

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

    NASA Astrophysics Data System (ADS)

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

    2016-03-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2016-07-01

    The problem of measuring the deformability of red blood cells in shear flow by laser diffractometry (ektacytometry) is considered. New diffractometric equations are obtained, which relate the parameters of the diffraction pattern to the characteristics of the erythrocyte ensemble, such as mean deformability as well as width and asymmetry of the erythrocytes distribution in deformability. A feature of these equations is that they include only geometric parameters of the diffraction pattern but do not contain its energy parameters. Basing on these equations, we propose a new data processing algorithm for the laser ektacytometry of red blood cells.

  11. Removal by centrifugation of leukocytes and red cells from apheresis platelets.

    PubMed

    Kiraly, T; Kakaiya, R M; Cable, R G

    1984-01-01

    Platelets prepared by discontinuous flow centrifugation contain significant numbers of leukocytes and red cells. Platelet products often are centrifuged further to remove this cellular "contamination." A method is described by which platelet products obtained by cytapheresis were prepared using an additional slow centrifugation step (121 X g for 7.5 minutes). In a production environment, we removed an average of 97 percent of leukocytes and most of the contaminating red cells with this method, while retaining 89 percent of the platelets in the final product. This method is an improvement over methods described previously and was consistently effective in routine use.

  12. Particle Method Computation of the Red Blood Cell Motion in Malaria Infection

    NASA Astrophysics Data System (ADS)

    Yamaguchi, Takami; Imai, Yosuke; Ishikawa, Takuji

    2010-09-01

    We developed a numerical model of blood flow in malaria infection. Our model was based on a particle method. All the components of blood were represented by finite number of particles. The membrane of red blood cells was modeled by triangular network of membrane particles. Stretch resistance and bending resistance were considered. The force generated by the deformation of membrane was substituted into the force term of Navier-Stokes equations only for membrane particles. The malaria parasite was assumed as a rigid object. Some interesting behavior of the infected and healthy red blood cells were simulated.

  13. Development of artificial red cells (ARC) produced by γ-ray induced polymerization of liposomes

    NASA Astrophysics Data System (ADS)

    Akama, K.; Awai, K.; Tokuyama, S.; Satoh, T.; Hosoi, F.; Omichi, H.

    1995-08-01

    Artificial red cells (ARC) are prepared by encapsulating Hb with a polymerizable phospholipid. The polymerization of the vesicles were carried out with the irradiation of γ-rays. The irradiated ARC are physically more stable than any other known liposome type blood substitutes. Because of this stability, they can be easily stored under frozen condition for a long time. No significant changes were observed in vivo study with rats in which ARC were injected intravenously. The oxygen transport capacity of ARC was similar to that of native red blood cells.

  14. Bone marrow transplantation for CVID-like humoral immune deficiency associated with red cell aplasia.

    PubMed

    Sayour, Elias J; Mousallem, Talal; Van Mater, David; Wang, Endi; Martin, Paul; Buckley, Rebecca H; Barfield, Raymond C

    2016-10-01

    Patients with common variable immunodeficiency (CVID) have a higher incidence of autoimmune disease, which may mark the disease onset; however, anemia secondary to pure red cell aplasia is an uncommon presenting feature. Here, we describe a case of CVID-like humoral immune deficiency in a child who initially presented with red cell aplasia and ultimately developed progressive bone marrow failure. Although bone marrow transplantation (BMT) has been associated with high mortality in CVID, our patient was successfully treated with a matched sibling BMT and engrafted with >98% donor chimerism and the development of normal antibody titers to diphtheria and tetanus toxoids. PMID:27273469

  15. Erythrokinetics: quantitative measurements of red cell production and destruction in normal subjects and patients with anemia.

    PubMed

    Giblett, Eloise R; Coleman, Daniel H; Pirzio-Biroli, Giacomo; Donohue, Dennis M; Motulsky, Arno G; Finch, Clement A

    2016-03-17

    To study erythropoiesis and anemia, one must have a firm foundation of indices that accurately measure red blood cell production and destruction. This paper, authored by hematology legends Arno G. Motulsky and Clement A. Finch, provides that foundation. Using methods that would not be approved in today's environment, the authors studied a cohort of normal healthy patients and an equal number of patients with different forms of anemia. The results confirm a reciprocal model of red cell production and destruction, show that anemia can be the result of either underproduction (a regenerative anemia or ineffective erythropoiesis) or increased destruction, and define parameters for distinguishing these 2 possibilities that are still widely used today.

  16. Use of a solid phase red blood cell adherence method for pretransfusion platelet compatibility testing.

    PubMed

    Rachel, J M; Summers, T C; Sinor, L T; Plapp, F V

    1988-07-01

    A solid phase red blood cell adherence method has been used for platelet antibody detection and crossmatching for refractory platelet recipients. Patient sera were first screened for HLA or platelet-specific antibodies, then crossmatched with potential apheresis platelet donors. The overall correlation of platelet crossmatch results with transfusion outcome was 97% in patients with no evidence of nonimmune platelet destruction. The solid phase red blood cell adherence method provided a feasible and effective alternative to HLA matching as a means of donor selection for refractory platelet recipients. The speed and simplicity of this method may allow most hospital laboratories to perform platelet antibody screening before routine platelet transfusions.

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

    SciTech Connect

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

    2006-02-20

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

  18. Flow of a circulating tumor cell and red blood cells in microvessels

    NASA Astrophysics Data System (ADS)

    Takeishi, Naoki; Imai, Yohsuke; Yamaguchi, Takami; Ishikawa, Takuji

    2015-12-01

    Quantifying the behavior of circulating tumor cells (CTCs) in the blood stream is of fundamental importance for understanding metastasis. Here, we investigate the flow mode and velocity of CTCs interacting with red blood cells (RBCs) in various sized microvessels. The flow of leukocytes in microvessels has been described previously; a leukocyte forms a train with RBCs in small microvessels and exhibits margination in large microvessels. Important differences in the physical properties of leukocytes and CTCs result from size. The dimensions of leukocytes are similar to those of RBCs, but CTCs are significantly larger. We investigate numerically the size effects on the flow mode and the cell velocity, and we identify similarities and differences between leukocytes and CTCs. We find that a transition from train formation to margination occurs when (R -a ) /tR≈1 , where R is the vessel radius, a is the cell radius, and tR is the thickness of RBCs, but that the motion of RBCs differs from the case of leukocytes. Our results also show that the velocities of CTCs and leukocytes are larger than the average blood velocity, but only CTCs move faster than RBCs for microvessels of R /a ≈1.5 -2.0 . These findings are expected to be useful not only for understanding metastasis, but also for developing microfluidic devices.

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

    NASA Astrophysics Data System (ADS)

    Wang, Tong; Rongin, Uwitije; Xing, Zhongwen

    2016-02-01

    Blood exhibits a heterogeneous nature of hematocrit, velocity, and effective viscosity in microcapillaries. Microvascular bifurcations have a significant influence on the distribution of the blood cells and blood flow behavior. This paper presents a simulation study performed on the two-dimensional motions and deformation of multiple red blood cells in microvessels with diverging and converging bifurcations. Fluid dynamics and membrane mechanics were incorporated. Effects of cell shape, hematocrit, and deformability of the cell membrane on rheological behavior of the red blood cells and the hemodynamics have been investigated. It was shown that the blood entering the daughter branch with a higher flow rate tended to receive disproportionally more cells. The results also demonstrate that red blood cells in microvessels experienced lateral migration in the parent channel and blunted velocity profiles in both straight section and daughter branches, and this effect was influenced by the shape and the initial position of the cells, the hematocrit, and the membrane deformability. In addition, a cell free region around the tip of the confluence was observed. The simulation results are qualitatively consistent with existing experimental findings. This study may provide fundamental knowledge for a better understanding of hemodynamic behavior of micro-scale blood flow.

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

    PubMed Central

    Wang, Tong; Rongin, Uwitije; Xing, Zhongwen

    2016-01-01

    Blood exhibits a heterogeneous nature of hematocrit, velocity, and effective viscosity in microcapillaries. Microvascular bifurcations have a significant influence on the distribution of the blood cells and blood flow behavior. This paper presents a simulation study performed on the two-dimensional motions and deformation of multiple red blood cells in microvessels with diverging and converging bifurcations. Fluid dynamics and membrane mechanics were incorporated. Effects of cell shape, hematocrit, and deformability of the cell membrane on rheological behavior of the red blood cells and the hemodynamics have been investigated. It was shown that the blood entering the daughter branch with a higher flow rate tended to receive disproportionally more cells. The results also demonstrate that red blood cells in microvessels experienced lateral migration in the parent channel and blunted velocity profiles in both straight section and daughter branches, and this effect was influenced by the shape and the initial position of the cells, the hematocrit, and the membrane deformability. In addition, a cell free region around the tip of the confluence was observed. The simulation results are qualitatively consistent with existing experimental findings. This study may provide fundamental knowledge for a better understanding of hemodynamic behavior of micro-scale blood flow. PMID:26830454

  1. 7 CFR 51.2338 - Standard pack.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... packed in containers with cell compartments, cardboard fillers or molded trays shall be of proper size for the cells, fillers, or molds in which they are packed, and conform to the marked count. (2) In... angles to a line from stem to blossom end. (f) In order to allow for variations incident to proper...

  2. 7 CFR 51.2338 - Standard pack.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... packed in containers with cell compartments, cardboard fillers or molded trays shall be of proper size for the cells, fillers, or molds in which they are packed, and conform to the marked count. (2) In... angles to a line from stem to blossom end. (f) In order to allow for variations incident to proper...

  3. 7 CFR 51.2338 - Standard pack.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    .... (c) Boxes, flats, lugs, or cartons: (1) Fruit packed in containers with cell compartments, cardboard fillers or molded trays shall be of proper size for the cells, fillers, or molds in which they are packed...” means the greatest dimension measured at right angles to a line from stem to blossom end. (f) In...

  4. 7 CFR 51.3152 - Standard pack.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...) Nectarines packed in containers equipped with cell compartments, cardboard fillers or molded trays shall be of the proper size for the cells, fillers, or molds in which they are packed, and the number of... angles to a line from stem to blossom end of the fruit. (h) Tolerances. In order to allow for...

  5. 7 CFR 51.2338 - Standard pack.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... packed in containers with cell compartments, cardboard fillers or molded trays shall be of proper size for the cells, fillers, or molds in which they are packed, and conform to the marked count. (2) In... angles to a line from stem to blossom end. (f) In order to allow for variations incident to proper...

  6. 7 CFR 51.3152 - Standard pack.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...) Nectarines packed in containers equipped with cell compartments, cardboard fillers or molded trays shall be of the proper size for the cells, fillers, or molds in which they are packed, and the number of... angles to a line from stem to blossom end of the fruit. (h) Tolerances. In order to allow for...

  7. 7 CFR 51.2338 - Standard pack.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    .... (c) Boxes, flats, lugs, or cartons: (1) Fruit packed in containers with cell compartments, cardboard fillers or molded trays shall be of proper size for the cells, fillers, or molds in which they are packed...” means the greatest dimension measured at right angles to a line from stem to blossom end. (f) In...

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

    NASA Astrophysics Data System (ADS)

    Crowl Erickson, Lindsay; Fogelson, Aaron

    2009-11-01

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

  9. Red cell antibodies and low ionic strength: a study with enzyme-linked antiglobulin test.

    PubMed

    Leikola, J; Perkins, H A

    1980-01-01

    Alloantibody uptake on red blood cells was quantified with an accurate and reproducible enzyme-linked antiglobulin test. The uptake of anti-D, anti-Fy2 and anti-JK3 was markedly accelerated by low ionic strength salt solution (LISS) with a final ionic strength of 0.05 M. Near maximum uptake occurred within ten minutes at room temperature which corresponded to 60 minutes in saline at 37 C. Papain treatment of red blood cells increased the amount of anti-D bound, and there was no difference whether or not the papain-treated cells were suspended in LISS. In contrast, the uptake of IgG anti-A and anti-Leb was not accelerated by LISS, nor did LISS increase the rate of binding of antiblogulin to IgG antibody-coated red blood cells. We suggest this may be explained by the fact that the ABH and Lewis antigens (as well as bound IgG antibodies) extend beyond the "ionic cloud" surrounding the red blood cell. Antibody binding in the presence of albumin was approximately the same as in saline; but if the albumin was first dialyzed against LISS, the reaction was markedly accelerated and the final antibody uptake somewhat higher than in LISS alone.

  10. Binding of DTNB to band 3 in the human red cell membrane.

    PubMed

    Toon, M R; Dorogi, P L; Lukacovic, M F; Solomon, A K

    1985-08-27

    Inhibition of red cell water transport by the sulfhydryl reagent 5,5'-dithiobis(2-nitrobenzoic acid) (DTNB) has been reported by Naccache and Sha'afi ((1974) J. Cell Physiol. 84, 449-456) but other investigators have not been able to confirm this observation. Brown et al. ((1975) Nature 254, 523-525) have shown that, under appropriate conditions, DTNB binds only to band 3 in the red cell membrane. We have made a detailed investigation of DTNB binding to red cell membranes that had been treated with the sulfhydryl reagent N-ethylmaleimide (NEM), and our results confirm the observation of Brown et al. Since this covalent binding site does not react with either N-ethylmaleimide or the sulfhydryl reagent pCMBS (p-chloromercuribenzenesulfonate), its presence has not previously been reported. This covalent site does not inhibit water transport nor does it affect any transport process we have studied. There is an additional low-affinity (non-covalent) DTNB site that Reithmeier ((1983) Biochim. Biophys. Acta 732, 122-125) has shown to inhibit anion transport. In N-ethylmaleimide-treated red cells, we have found that this binding site inhibits water transport and that the inhibition can be partially reversed by the specific stilbene anion exchange transport inhibitor 4,4'-diisothiocyanostilbene-2,2'-disulfonate (DIDS), thus linking water transport to anion exchange. DTNB binding to this low-affinity site also inhibits ethylene glycol and methyl urea transport with the same KI as that for water inhibition, thus linking these transport systems to that for water and anions. These results support the view that band 3 is a principal constituent of the red cell aqueous channel, through which urea and ethylene glycol also enter the cell. PMID:2992587

  11. Red Raspberry Phenols Inhibit Angiogenesis: A Morphological and Subcellular Analysis Upon Human Endothelial Cells.

    PubMed

    Sousa, M; Machado, V; Costa, R; Figueira, M E; Sepodes, B; Barata, P; Ribeiro, L; Soares, R

    2016-07-01

    Polyphenols are a class of natural compounds whose potential as antioxidant, anti-inflammatory, and anti-angiogenesis has been reported in many pathological conditions. Red raspberry extract, rich in polyphenols, has been reported to exert anti-inflammatory effects and prevent cell proliferation in distinct animal models. However, the signaling pathways involved remain unknown. Herein, we used human microvascular endothelial cells (HMVECs) to determine the influence of red raspberry phenolic compound extract concentrations, ranging from 10 to 250 µg gallic acid equivalents (GAE)/mL, on endothelium viability (MTS assay), proliferation (BrdU incorporation), migration (injury assay), and capillary-like structures formation (Matrigel assay). Protein expression in cell lysates was determined by Western blot analysis. We showed that red raspberry extracts reduced cell viability (GI50  = 87,64 ± 6,59 μg GAE/mL) and proliferation in a dose-dependent manner. A significant abrogation of cells ability to migrate to injured areas, even at low concentrations, was observed by injury assay. Cell assembly into capillary-like structures on Matrigel also decreased in a dose dependent-manner for higher extract concentrations, as well as the number of branching points per unit of area. Protein expression analysis showed a dose-dependent decrease in Phospho-VEGFR2 expression, implying abrogation of VEGF signaling activity. We also showed for the first time that red raspberry phenolic compounds induce the rearrangement of filamentous actin cytoskeleton, with an isotropy increase found for higher testing concentrations. Taken together, our findings corroborate the anti-angiogenic potential of red raspberry phenolic compounds and provide new insights into their mode of action upon endothelium. J. Cell. Biochem. 117: 1604-1612, 2016. © 2015 Wiley Periodicals, Inc.

  12. A Lattice Boltzmann Fictitious Domain Method for Modeling Red Blood Cell Deformation and Multiple-Cell Hydrodynamic Interactions in Flow

    SciTech Connect

    Shi, Xing; Lin, Guang; Zou, Jianfeng; Fedosov, Dmitry A.

    2013-07-20

    To model red blood cell (RBC) deformation in flow, the recently developed LBM-DLM/FD method ([Shi and Lim, 2007)29], derived from the lattice Boltzmann method and the distributed Lagrange multiplier/fictitious domain methodthe fictitious domain method, is extended to employ the mesoscopic network model for simulations of red blood cell deformation. The flow is simulated by the lattice Boltzmann method with an external force, while the network model is used for modeling red blood cell deformation and the fluid-RBC interaction is enforced by the Lagrange multiplier. To validate parameters of the RBC network model, sThe stretching numerical tests on both coarse and fine meshes are performed and compared with the corresponding experimental data to validate the parameters of the RBC network model. In addition, RBC deformation in pipe flow and in shear flow is simulated, revealing the capacity of the current method for modeling RBC deformation in various flows.

  13. Ferric carboxymaltose with or without erythropoietin for the prevention of red-cell transfusions in the perioperative period of osteoporotic hip fractures: a randomized contolled trial. The PAHFRAC-01 project

    PubMed Central

    2012-01-01

    Background Around one third to one half of patients with hip fractures require red-cell pack transfusion. The increasing incidence of hip fracture has also raised the need for this scarce resource. Additionally, red-cell pack transfusions are not without complications which may involve excessive morbidity and mortality. This makes it necessary to develop blood-saving strategies. Our objective was to assess safety, efficacy, and cost-effictveness of combined treatment of i.v. ferric carboxymaltose and erythropoietin (EPOFE arm) versus i.v. ferric carboxymaltose (FE arm) versus a placebo (PLACEBO arm) in reducing the percentage of patients who receive blood transfusions, as well as mortality in the perioperative period of hip fracture intervention. Methods/Design Multicentric, phase III, randomized, controlled, double blinded, parallel groups clinical trial. Patients > 65 years admitted to hospital with a hip fracture will be eligible to participate. Patients will be treated with either a single dosage of i.v. ferric carboxymaltose of 1 g and subcutaneous erythropoietin (40.000 IU), or i.v. ferric carboxymaltose and subcutaneous placebo, or i.v. placebo and subcutaneous placebo. Follow-up will be performed until 60 days after discharge, assessing transfusion needs, morbidity, mortality, safety, costs, and health-related quality of life. Intention to treat, as well as per protocol, and incremental cost-effectiveness analysis will be performed. The number of recruited patients per arm is set at 102, a total of 306 patients. Discussion We think that this trial will contribute to the knowledge about the safety and efficacy of ferric carboxymaltose with/without erythropoietin in preventing red-cell pack transfusions in patients with hip fracture. ClinicalTrials.gov identifier: NCT01154491. PMID:22353604

  14. Dynamic quantitative microscopy and nanoscopy of red blood cells in sickle cell disease

    NASA Astrophysics Data System (ADS)

    Shaked, Natan T.; Satterwhite, Lisa L.; Telen, Marilyn J.; Truskey, George A.; Wax, Adam

    2012-03-01

    We have applied wide-field digital interferometric techniques to quantitatively image sickle red blood cells (RBCs) [1] in a noncontact label-free manner, and measure the nanometer-scale fluctuations in their thickness as an indication of their stiffness. The technique can simultaneously measure the fluctuations for multiple spatial points on the RBC and thus yields a map describing the stiffness of each RBC in the field of view. Using this map, the local rigidity regions of the RBC are evaluated quantitatively. Since wide-field digital interferometry is a quantitative holographic imaging technique rather than one-point measurement, it can be used to simultaneously evaluate cell transverse morphology plus thickness in addition to its stiffness profile. Using this technique, we examine the morphology and dynamics of RBCs from individuals who suffer from sickle cell disease, and find that the sickle RBCs are significantly stiffer than healthy RBCs. Furthermore, we show that the technique is sensitive enough to distinguish various classes of sickle RBCs, including sickle RBCs with visibly-normal morphology, compared to the stiffer crescent-shaped sickle RBCs.

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

    PubMed Central

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

    2015-01-01

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

  16. SiR–Hoechst is a far-red DNA stain for live-cell nanoscopy

    PubMed Central

    Lukinavičius, Gražvydas; Blaukopf, Claudia; Pershagen, Elias; Schena, Alberto; Reymond, Luc; Derivery, Emmanuel; Gonzalez-Gaitan, Marcos; D'Este, Elisa; Hell, Stefan W.; Wolfram Gerlich, Daniel; Johnsson, Kai

    2015-01-01

    Cell-permeable DNA stains are popular markers in live-cell imaging. Currently used DNA stains for live-cell imaging are either toxic, require illumination with blue light or are not compatible with super-resolution microscopy, thereby limiting their utility. Here we describe a far-red DNA stain, SiR–Hoechst, which displays minimal toxicity, is applicable in different cell types and tissues, and is compatible with super-resolution microscopy. The combination of these properties makes this probe a powerful tool for live-cell imaging. PMID:26423723

  17. SiR-Hoechst is a far-red DNA stain for live-cell nanoscopy.

    PubMed

    Lukinavičius, Gražvydas; Blaukopf, Claudia; Pershagen, Elias; Schena, Alberto; Reymond, Luc; Derivery, Emmanuel; Gonzalez-Gaitan, Marcos; D'Este, Elisa; Hell, Stefan W; Gerlich, Daniel Wolfram; Johnsson, Kai

    2015-10-01

    Cell-permeable DNA stains are popular markers in live-cell imaging. Currently used DNA stains for live-cell imaging are either toxic, require illumination with blue light or are not compatible with super-resolution microscopy, thereby limiting their utility. Here we describe a far-red DNA stain, SiR-Hoechst, which displays minimal toxicity, is applicable in different cell types and tissues, and is compatible with super-resolution microscopy. The combination of these properties makes this probe a powerful tool for live-cell imaging.

  18. Quasi-elastic light scattering studies of membrane motion in single red blood cells.

    PubMed Central

    Tishler, R B; Carlson, F D

    1987-01-01

    Studies of red blood cells (RBCs) and RBC ghosts, using a quasi-elastic light scattering (QELS) microscope spectrometer, have identified the membrane as the primary source of the light scattering signal. This is the first report in which motion of the cell membrane has been demonstrated to be the primary source of the QELS signal from a cell. Cytoplasmic changes induced in the RBC by varying the osmotic strength of the medium were also detected using this technique. Comparison of the data from white blood cells (WBCs) with the RBC data demonstrated significant differences between different types of cells. PMID:3607216

  19. Low-level red laser therapy alters effects of ultraviolet C radiation on Escherichia coli cells

    PubMed Central

    Canuto, K.S.; Sergio, L.P.S.; Guimarães, O.R.; Geller, M.; Paoli, F.; Fonseca, A.S.

    2015-01-01

    Low-level lasers are used at low power densities and doses according to clinical protocols supplied with laser devices or based on professional practice. Although use of these lasers is increasing in many countries, the molecular mechanisms involved in effects of low-level lasers, mainly on DNA, are controversial. In this study, we evaluated the effects of low-level red lasers on survival, filamentation, and morphology of Escherichia colicells that were exposed to ultraviolet C (UVC) radiation. Exponential and stationary wild-type and uvrA-deficientE. coli cells were exposed to a low-level red laser and in sequence to UVC radiation. Bacterial survival was evaluated to determine the laser protection factor (ratio between the number of viable cells after exposure to the red laser and UVC and the number of viable cells after exposure to UVC). Bacterial filaments were counted to obtain the percentage of filamentation. Area-perimeter ratios were calculated for evaluation of cellular morphology. Experiments were carried out in duplicate and the results are reported as the means of three independent assays. Pre-exposure to a red laser protected wild-type and uvrA-deficient E. coli cells against the lethal effect of UVC radiation, and increased the percentage of filamentation and the area-perimeter ratio, depending on UVC fluence and physiological conditions in the cells. Therapeutic, low-level red laser radiation can induce DNA lesions at a sub-lethal level. Consequences to cells and tissues should be considered when clinical protocols based on this laser are carried out. PMID:26445338

  20. Low-level red laser therapy alters effects of ultraviolet C radiation on Escherichia coli cells.

    PubMed

    Canuto, K S; Sergio, L P S; Guimarães, O R; Geller, M; Paoli, F; Fonseca, A S

    2015-10-01

    Low-level lasers are used at low power densities and doses according to clinical protocols supplied with laser devices or based on professional practice. Although use of these lasers is increasing in many countries, the molecular mechanisms involved in effects of low-level lasers, mainly on DNA, are controversial. In this study, we evaluated the effects of low-level red lasers on survival, filamentation, and morphology of Escherichia colicells that were exposed to ultraviolet C (UVC) radiation. Exponential and stationary wild-type and uvrA-deficientE. coli cells were exposed to a low-level red laser and in sequence to UVC radiation. Bacterial survival was evaluated to determine the laser protection factor (ratio between the number of viable cells after exposure to the red laser and UVC and the number of viable cells after exposure to UVC). Bacterial filaments were counted to obtain the percentage of filamentation. Area-perimeter ratios were calculated for evaluation of cellular morphology. Experiments were carried out in duplicate and the results are reported as the means of three independent assays. Pre-exposure to a red laser protected wild-type and uvrA-deficient E. coli cells against the lethal effect of UVC radiation, and increased the percentage of filamentation and the area-perimeter ratio, depending on UVC fluence and physiological conditions in the cells. Therapeutic, low-level red laser radiation can induce DNA lesions at a sub-lethal level. Consequences to cells and tissues should be considered when clinical protocols based on this laser are carried out.

  1. Directly observed reversible shape changes and hemoglobin stratification during centrifugation of human and Amphiuma red blood cells.

    PubMed

    Hoffman, Joseph F; Inoué, Shinya

    2006-02-21

    This paper describes changes that occur in human and Amphiuma red blood cells observed during centrifugation with a special microscope. Dilute suspensions of cells were layered, in a centrifuge chamber, above an osmotically matched dense solution, containing Nycodenz, Ficoll, or Percoll (Pharmacia) that formed a density gradient that allowed the cells to slowly settle to an equilibrium position. Biconcave human red blood cells moved downward at low forces with minimum wobble. The cells oriented vertically when the force field was increased and Hb sedimented as the lower part of each cell became bulged and assumed a "bag-like" shape. The upper centripetal portion of the cell became thinner and remained biconcave. These changes occurred rapidly and were completely reversible upon lowering the centrifugal force. Bag-shaped cells, upon touching red cells in rouleau, immediately reverted to biconcave disks as they flipped onto a stack. Amphiuma red cells displayed a different type of reversible stratification and deformation at high force fields. Here the cells became stretched, with the nucleus now moving centrifugally, the Hb moving centripetally, and the bottom of the cells becoming thinner and clear. Nevertheless, the distribution of the marginal bands at the cells' rim was unchanged. We conclude that centrifugation, per se, while changing a red cell's shape and the distribution of its intracellular constituents, does so in a completely reversible manner. Centrifugation of red cells harboring altered or missing structural elements could provide information on shape determinants that are still unexplained. PMID:16477016

  2. Red emission fluorescent probes for visualization of monoamine oxidase in living cells

    PubMed Central

    Li, Ling-Ling; Li, Kun; Liu, Yan-Hong; Xu, Hao-Ran; Yu, Xiao-Qi

    2016-01-01

    Here we report two novel red emission fluorescent probes for the highly sensitive and selective detection of monoamine oxidase (MAO) with large Stokes shift (227 nm). Both of the probes possess solid state fluorescence and can accomplish the identification of MAO on test papers. The probe MAO-Red-1 exhibited a detection limit down to 1.2 μg mL−1 towards MAO-B. Moreover, the cleavage product was unequivocally conformedby HPLC and LCMS and the result was in accordance with the proposed oxidative deamination mechanism. The excellent photostability of MAO-Red-1 was proved both in vitro and in vivo through fluorescent kinetic experiment and laser exposure experiment of confocal microscopy, respectively. Intracellular experiments also confirmed the low cytotoxity and exceptional cell imaging abilities of MAO-Red-1. It was validated both in HeLa and HepG2 cells that MAO-Red-1 was capable of reporting MAO activity through the variation of fluorescence intensity. PMID:27499031

  3. Monomeric Garnet, a far-red fluorescent protein for live-cell STED imaging

    PubMed Central

    Hense, Anika; Prunsche, Benedikt; Gao, Peng; Ishitsuka, Yuji; Nienhaus, Karin; Ulrich Nienhaus, G.

    2015-01-01

    The advancement of far-red emitting variants of the green fluorescent protein (GFP) is crucially important for imaging live cells, tissues and organisms. Despite notable efforts, far-red marker proteins still need further optimization to match the performance of their green counterparts. Here we present mGarnet, a robust monomeric marker protein with far-red fluorescence peaking at 670 nm. Thanks to its large extinction coefficient of 95,000 M−1cm−1, mGarnet can be efficiently excited with 640-nm light on the red edge of its 598-nm excitation band. A large Stokes shift allows essentially the entire fluorescence emission to be collected even with 640-nm excitation, counterbalancing the lower fluorescence quantum yield of mGarnet, 9.1%, that is typical of far-red FPs. We demonstrate an excellent performance as a live-cell fusion marker in STED microscopy, using 640 nm excitation and 780 nm depletion wavelengths. PMID:26648024

  4. Red emission fluorescent probes for visualization of monoamine oxidase in living cells.

    PubMed

    Li, Ling-Ling; Li, Kun; Liu, Yan-Hong; Xu, Hao-Ran; Yu, Xiao-Qi

    2016-01-01

    Here we report two novel red emission fluorescent probes for the highly sensitive and selective detection of monoamine oxidase (MAO) with large Stokes shift (227 nm). Both of the probes possess solid state fluorescence and can accomplish the identification of MAO on test papers. The probe MAO-Red-1 exhibited a detection limit down to 1.2 μg mL(-1) towards MAO-B. Moreover, the cleavage product was unequivocally conformedby HPLC and LCMS and the result was in accordance with the proposed oxidative deamination mechanism. The excellent photostability of MAO-Red-1 was proved both in vitro and in vivo through fluorescent kinetic experiment and laser exposure experiment of confocal microscopy, respectively. Intracellular experiments also confirmed the low cytotoxity and exceptional cell imaging abilities of MAO-Red-1. It was validated both in HeLa and HepG2 cells that MAO-Red-1 was capable of reporting MAO activity through the variation of fluorescence intensity. PMID:27499031

  5. Red emission fluorescent probes for visualization of monoamine oxidase in living cells.

    PubMed

    Li, Ling-Ling; Li, Kun; Liu, Yan-Hong; Xu, Hao-Ran; Yu, Xiao-Qi

    2016-08-08

    Here we report two novel red emission fluorescent probes for the highly sensitive and selective detection of monoamine oxidase (MAO) with large Stokes shift (227 nm). Both of the probes possess solid state fluorescence and can accomplish the identification of MAO on test papers. The probe MAO-Red-1 exhibited a detection limit down to 1.2 μg mL(-1) towards MAO-B. Moreover, the cleavage product was unequivocally conformedby HPLC and LCMS and the result was in accordance with the proposed oxidative deamination mechanism. The excellent photostability of MAO-Red-1 was proved both in vitro and in vivo through fluorescent kinetic experiment and laser exposure experiment of confocal microscopy, respectively. Intracellular experiments also confirmed the low cytotoxity and exceptional cell imaging abilities of MAO-Red-1. It was validated both in HeLa and HepG2 cells that MAO-Red-1 was capable of reporting MAO activity through the variation of fluorescence intensity.

  6. Immunoelectrophoresis of red blood cells performed on microcapillary chips.

    PubMed

    Ichiki, Takanori; Ujiie, Tatekazu; Shinbashi, Satomi; Okuda, Tomoko; Horiike, Yasuhiro

    2002-07-01

    Immunoanalysis of blood cells on a microcapillary electrophoresis (nuCE) chip has been studied using sheep erythrocytes (ShE) as an example. Two different buffer solutions, the phosphate-buffered saline (PBS) and the gelatin veronal buffer (GVB) were examined in regard to the electrokinetic transport behavior of ShE suspended in these solutions inside the rectangular channel engraved on a quartz chip. This clarified two advantages of the use of GVB for on-chip cell electrophoresis: gelatin coatings prevent (i) nonspecific sticking of ShE on the channel wall, and cause (ii) an appreciable reduction in the zeta potential of the wall suppressing the electroosmotic flow of the buffer solution. As a result ShE suspended in the GVB can smoothly migrate from the cathode to the anode, which is the opposite flow direction of immunoglobulin G (IgG) antibodies under the physiological pH condition of 7.4. Based on these results, on-chip capillary cell immunoelectrophoresis of ShE and rabbit anti ShE antibodies (IgG) have been proposed and successfully accomplished using the GVB. It is demonstrated that the variation of the cell migration velocity originating from the change in the surface charge after binding antibodies is applicable to the fast detection of immune reactions and also to single-cell typing.

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  8. First haemorheological experiment on NASA space shuttle 'Discovery' STS 51-C: aggregation of red cells.

    PubMed

    Dintenfass, L; Osman, P D; Jedrzejczyk, H

    1985-01-01

    The 'secret' D.O.D. Mission on flight STS 51-C also carried nearly 100 kg of automated instrumentation of the Australian experiment on aggregation of red cells ("ARC"). The automated Slit-Capillary Photo Viscometer contained blood samples from subjects with history of coronary heart disease, cancer of the colon, insulin-dependent diabetes, etc., as well as normals. The experiment ran for nine hours, according to the program of its microcomputers. When shuttle landed and instrumentation recovered and opened in the presence of NASA quality control officers, it was obvious that experiment was a success. Tentative and preliminary results can be summarized as follows: red cells did not change shape under zero gravity; red cells do aggregate under zero gravity, although the size of aggregates is smaller than on the ground; the morphology of aggregates of red cells appears to be of rouleaux type under zero gravity, notwithstanding the fact that pathological blood was used. These results will have to be confirmed in the future flights. The background and history of development of the project are described, and put into context of our general haemorheological studies.

  9. Detection of an ileal cavernous hemangioma by technetium-99m red blood cell imaging

    SciTech Connect

    Holloway, H.; Johnson, J.; Sandler, M.

    1988-01-01

    Patients with arteriovenous malformations of the bowel may have multiple symptoms secondary to chronic blood loss. A case of ileal cavernous hemangioma detected by Tc-99m labeled red blood cell imaging in the absence of active gastrointestinal bleeding is presented.

  10. Modulation of red cell metabolism by states of decreased activation: comparison between states.

    PubMed

    Jevning, R; Wilson, A F; Pirkle, H; Guich, S; Walsh, R N

    1985-11-01

    Marked decline of red cell metabolism has been described during the acute state of decreased activation associated with the stylized mental technique of transcendental meditation (TM) in long-term meditators (5-10 years regular elicitation, TM instructors). It is not known whether unstylized rest is accompanied by a similar effect and it is not known what effector(s) may contribute to red cell metabolic changes in these states. In the present study ordinary, unstylized rest was found to be accompanied by small increase of red cell glycolytic rate. Apparently, either repeated elicitation of TM behavior or some special feature of this practice become associated with new mechanisms of metabolic control than those previously in operation. Although the data of this study do not permit isolation of the precise psychological determinants of this effect, the range of possible physiological effectors can be delimited. Blood pH, PCO2, PO2, and phosphate can be eliminated as significant for red cell metabolic control during both TM and rest, and based upon related studies, several known hormones such as insulin, T3, T4, arginine vasopressin, oxytocin, prolactin and growth hormone can also be eliminated as responsible effector(s).

  11. Pure red cell aplasia caused by parvovirus B19 in a heart transplant recipient.

    PubMed

    Invernizzi, Rosangela; Bastia, Raffaella; Quaglia, Federica

    2016-09-01

    A case of parvovirus B19-induced pure red cell aplasia occurring in a heart transplant recipient is reported. The diagnosis of this rare but clinically important complication can be suspected on the basis of the pathognomonic morphological features of the bone marrow. PMID:27648265

  12. Gallbladder visualization during technetium-99m-labeled red cell scintigraphy for gastrointestinal bleeding

    SciTech Connect

    Brill, D.R.

    1985-12-01

    Localization of radionuclide activity in the gallbladder was seen on delayed views following injection of 99mTc-labeled red blood cells for gastrointestinal bleeding in five patients. The mechanism for this unusual finding probably relates to labeling of heme, the biochemical precursor of bilirubin. All patients had had prior transfusions. All but one had severe renal impairment, probably an important predisposing factor.

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

    NASA Astrophysics Data System (ADS)

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

    2013-10-01

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

  14. The curious genomic path from leaky red cell to nephrotic kidney.

    PubMed

    Stewart, G W; Fricke, B

    2003-01-01

    The human red cell has proved to be an invaluable model cell for the study of many aspects of membrane structure and function. It has a series of transport pathways which mediate the movements of the univalent cations Na and K, which are either identical or similar to systems in other human tissues, including the human kidney. The balance between the energy-consuming NaK pump and a 'passive leak' component maintains a net deficit of cations within the cell, which defends the cell volume against osmotic swelling. There exist a series of dominantly inherited human red cell conditions, gathered under the generic title 'hereditary stomatocytoses', in which the so-called 'passive leak' to Na and K is pathologically increased. In the more severe variants this compromises the integrity of the cell and the patients suffer haemolytic anaemia. Some less severe variants present with pseudohyperkalaemia caused by loss of K from red cells on storage of blood at room temperature. The most severe variants show a deficiency in a widely distributed 'raft' protein known as stomatin. The stomatin protein is homologous to the 'podocin' protein, the gene for which is mutated in a recessively inherited form of nephrotic syndrome. Among other possible functions, both proteins could be involved in the trafficking of membrane proteins to and from the plasma membrane.

  15. Contamination of salvaged maternal blood by amniotic fluid and fetal red cells during elective Caesarean section

    PubMed Central

    Sullivan, I.; Faulds, J.; Ralph, C.

    2008-01-01

    Background Cell salvage in obstetrics is still a controversial subject and has yet to be fully embraced. The aim of this exploratory study was to measure amniotic fluid (AF), heparin, and fetal red cell contamination of washed filtered salvaged maternal blood and to investigate differences based on the number of suction devices used. Methods Patients undergoing elective Caesarean section were assigned alternately to one of two groups. In Group 1, all blood and AF was collected with one suction. In Group 2, AF was aspirated to waste with a second separate suction device before collection of any blood. Results In both groups, alpha-fetoprotein (AFP), squames cells, and heparin were significantly reduced (P<0.001) by the washing and filtering process. Mean AFP levels post-filtration were 2.58 IU ml−1 in Group 1 and 3.53 IU ml−1 in Group 2. Squames cells were completely removed in all but two cases. Fetal red blood cells were still present in the final product, range 0.13–4.35%. In Group 1, haemoglobin and haematocrit were higher than in Group 2, with lower white blood cell, AFP, and fetal red cell counts. Conclusions This study adds to the growing body of evidence that there is little or no possibility for AF contamination to enter the re-infusion system when used in conjunction with a leucodepletion filter. PMID:18515817

  16. Red blood cell micromanipulation with elliptical laser beam profile optical tweezers in different osmolarity conditions

    NASA Astrophysics Data System (ADS)

    Spyratou, E.; Makropoulou, M.; Serafetinides, A. A.

    2011-07-01

    In this work optical tweezers with elliptical beam profiles have been developed in order to examine the effect of optical force on fresh red blood cells (RBC) in isotonic, hypertonic and hypotonic buffer solutions. Considering that the optical force depends essentially on the cell surface and the cytoplasmic refractive index, it is obvious that biochemical modifications associated with different states of the cell will influence its behaviour in the optical trap. Line optical tweezers were used to manipulate simultaneously more than one red blood cell. After we have been manipulated a RBC with an elliptical laser beam profile in an isotonic or hypertonic buffer, we noticed that it rotates by itself when gets trapped by optical tweezers and undergoes folding. Further shape deformations can be observed attributed to the competition between alignment and rotational torque which are transferred by laser light to the cell. In hypotonic buffer RBCs become spherical and do not rotate or fold since the resultant force due to rays emerging from diametrically opposite points of the cell leads to zero torque. Manipulation of fresh red blood cells in isotonic solution by line optical tweezers leads to folding and elongation of trapped RBCs. Membrane elasticity properties such as bending modulus can be estimated by measuring RBC's folding time in function with laser power.

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

    PubMed

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

    2015-01-01

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

  18. Sugar Concentrations in Guard Cells of Vicia faba Illuminated with Red or Blue Light 1

    PubMed Central

    Poffenroth, Matthew; Green, David B.; Tallman, Gary

    1992-01-01

    Concentrations of soluble sugars in guard cells in detached, sonicated epidermis from Vicia faba leaves were analyzed quantitatively by high performance liquid chromatography to determine the extent to which sugars could contribute to changes in the osmotic potentials of guard cells during stomatal opening. Stomata were illuminated over a period of 4 hours with saturating levels of red or blue light, or a combination of red and blue light. When stomata were irradiated for 3 hours with red light (50 micromoles per square meter per second) in a solution of 5 millimolar KCl and 0.1 millimolar CaCl2, stomatal apertures increased a net maximum of 6.7 micrometers and the concentration of total soluble sugar was 289 femtomoles per guard cell (70% sucrose, 30% fructose). In an identical solution, 2.5 hours of irradiation with 25 micromoles per square meter per second of blue light caused a maximum net increase of 7.1 micrometers in stomatal aperture and the total soluble sugar concentration was 550 femtomoles per guard cell (91% sucrose, 9% fructose). Illumination with blue light at 25 micromoles per square meter per second in a solution lacking KCl caused a maximum net increase in stomatal aperture of 3.5 micrometers and the sugar concentration was 382 femtomoles per guard cell (82% sucrose, 18% fructose). In dual beam experiments, stomata irradiated with 50 micromoles per square meter per second of red light opened steadily with a concomitant increase in sugar production. Addition of 25 micromoles per square meter per second of blue light caused a further net gain of 3.7 micrometers in stomatal aperture and, after 2 hours, sugar concentrations had increased by an additional 138 femtomoles per guard cell. Experiments with 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU) were performed with epidermis illuminated with 50 micromoles per square meter per second of red light or with 25 micromoles per square meter per second of blue light in solutions containing or lacking KCl

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

    DOEpatents

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

    1988-07-05

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

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

    DOEpatents

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

    1988-01-01

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