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Sample records for packed red cell

  1. Sodium, potassium, water, and haemoglobin in the packed red cells of severe thalassaemia

    PubMed Central

    Choremis, C.; Economou-Mavrou, Cleopatra; Tsenghi, Christina

    1961-01-01

    Sodium, potassium, water, and the mean corpuscular haemoglobin concentration were determined in the packed erythrocytes of children with severe thalassaemia. The concentration of sodium in the packed red cells was higher than normal in a significant proportion of children with thalassaemia whereas potassium in the packed cells and sodium and potassium in the plasma were normal. On average, the cell water content was a little higher and the mean corpuscular haemoglobin concentration a little lower than normal. The cation concentrations in the packed cells of thalassaemia are compared with those in other anaemias. Similarities are pointed out between the sodium concentrations in the packed cells of thalassaemia and those from the foetus and children suffering from malnutrition. PMID:13879177

  2. Effects of 4000 rad irradiation on the in vitro storage properties of packed red cells

    SciTech Connect

    Moore, G.L.; Ledford, M.E.

    1985-11-01

    Immunosuppressed patients who require red cell transfusions receive irradiated (1500-3000 rad) packed red cells. These cells are irradiated immediately before infusion. If a large group of patients become immunosuppressed due to exposure to radiation or chemicals, the ability to supply large volumes of irradiated blood at the time of use might not be possible. An alternate solution to providing quantities of irradiated blood is to irradiate the units prior to storage. This study presents in vitro data comparing storage of paired packed red cell units either irradiated or not irradiated. Five units of fresh blood drawn into citrate-phosphate-dextrose-adenine (CPDA-1) were packed to a hematocrit of 75 +/- 1 percent, and then each unit was divided in two equal parts. One of each pair was irradiated (4000 rads), and both parts of each unit were stored for 35 days at 4 degrees C. Samples were analyzed every 7 days. Irradiation caused a slight drop in red cell adenosine triphosphate and 2,3 diphosphoglycerate and a slight increase in plasma hemoglobin compared to controls. Methemoglobin, pH, and glucose consumption were identical to the controls. The evidence indicates that irradiation did not cause biochemical or metabolic changes in the red cells that would lead us to suspect a difference between irradiated and nonirradiated stored red cells in function or viability. These negative findings require in vivo confirmation.

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

    PubMed

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

    2016-09-08

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

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

    DTIC Science & Technology

    2015-09-01

    A. Schreiber, MD September 2015 Air Force Research Laboratory 711th Human Performance Wing U.S. Air Force School of Aerospace Medicine...under standard conditions, but the Food and Drug Administration currently restricts their use to 14 days after thawing. The effect of longer term...transfusion with previously cryopreserved packed red blood cells is superior to that of aged units stored under standard conditions, but the Food and

  6. 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.

  7. Packed red blood cell transfusions as a risk factor for parenteral nutrition associated liver disease in premature infants

    PubMed Central

    D’Souza, Antoni; Algotar, Anushree; Pan, Ling; Schwarz, Steven M; Treem, William R; Valencia, Gloria; Rabinowitz, Simon S

    2016-01-01

    AIM To determine if packed red blood cell transfusions contribute to the development of parenteral nutrition associated liver disease. METHODS A retrospective chart review of 49 premature infants on parenteral nutrition for > 30 d who received packed red blood cell (PRBC) transfusions was performed. Parenteral nutrition associated liver disease was primarily defined by direct bilirubin (db) > 2.0 mg/dL. A high transfusion cohort was defined as receiving > 75 mL packed red blood cells (the median value). Kaplan-Meier plots estimated the median volume of packed red blood cells received in order to develop parenteral nutrition associated liver disease. RESULTS Parenteral nutritional associated liver disease (PNALD) was noted in 21 (43%) infants based on db. Among the 27 high transfusion infants, PNALD was present in 17 (64%) based on elevated direct bilirubin which was significantly greater than the low transfusion recipients. About 50% of the infants, who were transfused 101-125 mL packed red blood cells, developed PNALD based on elevation of direct bilirubin. All infants who were transfused more than 200 mL of packed red blood cells developed PNALD. Similar results were seen when using elevation of aspartate transaminase or alanine transaminase to define PNALD. CONCLUSION In this retrospective, pilot study there was a statistically significant correlation between the volume of PRBC transfusions received by premature infants and the development of PNALD. PMID:27872824

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

    PubMed Central

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

    2013-01-01

    Introduction Transfusions of one or more packed red blood cells is a widely strategy used in cardiac surgery, even after several evidences of increased morbidity and mortality. The world's blood shortage is also already evident. Objective To assess whether the risk of mortality is dose-de>pendent on the number of packed red blood cells transfused after coronary artery bypass graft. Methods Between June 2009 and July 2010, were analyzed 3010 patients: transfused and non-transfused. Transfused patients were divided into six groups according to the number of packed red blood cells received: one, two, three, four, five, six or more units, then we assess the mortality risk in each group after a year of coronary artery bypass graft. To calculate the odds ratio was used the multivariate logistic regression model. Results The increasing number of allogeneic packed red blood cells transfused results in an increasing risk of mortality, highlighting a dose-dependent relation. The odds ratio values increase with the increased number of packed red blood cells transfused. The death's gross odds ratio was 1.42 (P=0.165), 1.94 (P=0.005), 4.17; 4.22, 8.70, 33.33 (P<0.001) and the adjusted death's odds ratio was 1.22 (P=0.43), 1.52 (P=0.08); 2.85; 2.86; 4.91 and 17.61 (P<0.001), as they received one, two, three, four, five, six or more packed red blood cells, respectively. Conclusion The mortality risk is directly proportional to the number of packed red blood cells transfused in coronary artery bypass graft. The greater the amount of allogeneic blood transfused the greater the risk of mortality. The current transfusion practice needs to be reevaluated. PMID:24598957

  9. Effects of 4000-rad irradiation on the in vitro storage properties of packed red cells. Final report

    SciTech Connect

    Moore, G.L.; Ledford, M.E.

    1985-01-01

    Immunosuppressed patients who require red cell transfusions receive irradiated (1500-3000 rad) packed red cells. These cells are irradiated immediately before infusion. If a large group of patients become immunosuppressed due to exposure to radiation or chemicals, the ability to supply large volumes of irradiated blood at the time of use might not be possible. An alternate solution to providing quantities of irradiated blood is to irradiate the units prior to storage. This study presents in vitro data comparing storage of paired packed red cell units either irradiated or not irradiated. Five units of fresh blood drawn into citrate-phosphate-dextrose-adenine (CPDA-1) were packed to a hematocrit of 75 + or - 1%, and then each unit was divided in two equal parts. One of each pair was irradiated (4000 rads), and both parts of each unit were stored for 35 days at 4 C. Samples were analyzed every 7 days. Irradiation caused a slight drop in red cell adenosine triphosphate and 2,3 diphosphoglycerate and a slight increase in plasma hemoglobin compared to controls. Methemoglobin, pH, and glucose consumption were identical to the controls. The evidence indicates that irradiation did not cause biochemical or metabolic changes in the red cells that would lead us to suspect a difference between irradiated and nonirradiated stored red cells in function or viability. These negative findings require in vivo confirmation.

  10. Temporal sequence of major biochemical events during Blood Bank storage of packed red blood cells

    PubMed Central

    Karon, Brad S.; van Buskirk, Camille M.; Jaben, Elizabeth A.; Hoyer, James D.; Thomas, David D.

    2012-01-01

    Background. We used sensitive spectroscopic techniques to measure changes in Band 3 oligomeric state during storage of packed red blood cells (RBC); these changes were compared to metabolic changes, RBC morphology, cholesterol and membrane protein loss, phospholipid reorganisation of the RBC membrane, and peroxidation of membrane lipid. The aim of the study was to temporally sequence major biochemical events occurring during cold storage, in order to determine which changes may underlie the structural defects in stored RBC. Materials and methods. Fifteen RBC units were collected from normal volunteers and stored under standard blood bank conditions; both metabolic changes and lipid parameters were measured by multiple novel assays including a new mass spectrometric measurement of isoprostane (lipid peroxidation) and flow cytometric assessment of CD47 expression. Band 3 oligomeric state was assessed by time-resolved phosphorescence anisotropy, and RBC morphology by microscopy of glutaraldehyde-fixed RBC. Results. Extracellular pH decreased and extracellular potassium increased rapidly during cold storage. Band 3 on the RBC membrane aggregated into large oligomers early in the storage period and coincident with changes in RBC morphology. Membrane lipid changes, including loss of unesterified cholesterol, lipid peroxidation and expression of CD47, also changed early during the storage period. In contrast loss of acetylcholinesterase activity and haemolysis of RBC occurred late during storage. Discussion. Our results demonstrate that changes in the macromolecular organisation of membrane proteins on the RBC occur early in storage and suggest that lipid peroxidation and/or oxidative damage to the membrane are responsible for irreversible morphological changes and loss of function during red cell storage. PMID:22507860

  11. 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.

  12. 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

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

    DTIC Science & Technology

    2007-11-02

    Commission of the American Hospital Association, 0 the College of American Pathologists, and the Office of Biologics of the Food and Drug Administration [ FDA ...They have been approved for this use by the FDA . 2) There is documentation available to show that addition to the component is safe and efficacious... chlorpromazine hydrochloride. Seeman, Kwant, Sauks and Argent (1969) also found that many types of cells are protected or stabilized by a very wide variety

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

    DTIC Science & Technology

    2000-10-01

    the Office of Biologics of the Food and Drug Administration [ FDA ] are all involved in accrediting and regulating the collection, handling, and the...added to blood or components under either of the following conditions: 1) They have been approved for this use by the FDA . 2) There is...alcohol, and chlorpromazine hydrochloride. Seeman, Kwant, Sauks and Argent (1969) also found that many types of cells are protected or stabilized by a

  15. Use of Esophageal Hemoximetry to Assess the Effect of Packed Red Blood Cell Transfusion on Gastrointestinal Oxygenation in Newborn Infants.

    PubMed

    Vora, Farha M; Gates, Judy; Gerard, Kimberley; Hanson, Shawn; Applegate, Richard L; Blood, Arlin B

    2017-01-18

    Objectives There are no widely accepted methods of continuously monitoring gut oxygenation in the newborn during packed red blood cell transfusion. We investigated the use of an orally inserted light spectroscopy probe to measure lower esophageal oxyhemoglobin saturations (eStO2) before, during, and after transfusion and made comparisons with abdominal near-infrared spectroscopy (NIRS) and superior mesenteric artery (SMA) flow. Study Design Thirteen neonates with corrected gestational ages ranging from 22 weeks, 0 day to 37 weeks, 5 days were enrolled. eStO2 and NIRS measurements were recorded continuously for a 25-hour period starting 1 hour prior to starting the 4-hour transfusion. Transabdominal ultrasound was used to measure SMA flow prior to, upon completion, and 20 hours after the transfusion. Results Twelve infants completed the study. eStO2 was well-tolerated and was weakly (r = 0.06) correlated (p < 0.001) with NIRS. Compared with NIRS, eStO2 demonstrated a markedly greater variation in oxyhemoglobin values. NIRS and SMA flow measurements did not change, while eStO2 increased from 48 ± 5% and 45 ± 5% in the pre- and intratransfusion periods to 57 ± 4% in the posttransfusion period (p = 0.03). Conclusion Measurement of eStO2 is feasible in neonates and may provide a continuous and sensitive index of rapid changes in mesenteric oxygenation in this patient population.

  16. Safety and efficacy of packed red blood cell transfusions at different doses in very low birth weight infants

    PubMed Central

    Govande, Vinayak P.; Shetty, Ashita; Beeram, Madhava R.

    2016-01-01

    This double-blinded, randomized, crossover study evaluated the safety and effectiveness of 20 mL/kg aliquots of packed red blood cell (PRBC) transfusions versus 15 mL/kg aliquot transfusions in very low birth weight (VLBW) infants with anemia. The study enrolled 22 hemodynamically stable VLBW infants requiring PRBC transfusions, with a mean gestational age of 25.7 ± 2.2 weeks and birth weight of 804 ± 261 g. Each infant was randomized to receive one of two treatment sequences: 15 mL/kg followed by 20 mL/kg or 20 mL/kg followed by 15 mL/kg. The infants were monitored during and after transfusions, and the efficacy and safety of the treatments were evaluated. Infants had higher posttransfusion hemoglobin (13.2 g/dL vs 11.8 g/dL, P < 0.01) and hematocrit levels (38.6 g/dL vs 34.4 g/dL, P < 0.01) following 20 mL/kg PRBC transfusions when compared to 15 mL/kg transfusions. There were no differences in the incidence of tachypnea, hepatomegaly, edema, hypoxia, necrotizing enterocolitis, or vital sign instability between groups. In conclusion, high-volume PRBC transfusions (20 mL/kg) were associated with higher posttransfusion hemoglobin and hematocrit levels but no adverse effects. Higher-volume transfusions may reduce the need for multiple transfusions and therefore the number of donors the infant is exposed to. PMID:27034542

  17. Saline-expanded group O uncrossmatched packed red blood cells as an initial resuscitation fluid in severe shock.

    PubMed

    Schwab, C W; Civil, I; Shayne, J P

    1986-11-01

    Despite an excellent military experience with the use of the "universal donor" as an immediately available blood component, considerable reluctance to use uncrossmatched Group O packed cells (TOB) remains. In addition, problems continue with rapid blood acquisition in the emergency department. To study the safety of TOB used as an immediate resuscitation component, a 30-month prospective study of all patients arriving at a single trauma unit was undertaken. By protocol TOB (O-, female; O+, male) was delivered to the shock room prior to patient arrival and was expanded to 500 mL by adding 250 mL prewarmed saline (39.4 C) to the existing RBC unit. Transfusion was ordered on clinical signs of Class III or Class IV hemorrhage. Ninety-nine patients entered the protocol, receiving a total of 1,136 units of blood (11.5 units/patient). Four hundred ten units (4.1 units/patient) of uncrossmatched blood were administered on patient arrival--322 units of TOB and 88 units of type-specific blood (TSB). Seven patients (7.4%) had prior transfusions, and 14 (58%) women had prior pregnancies. Complications included disseminated intravascular coagulation, 12%; adult respiratory distress syndrome, 8%; and hepatitis, 1%. Forty-nine patients (49%) required massive transfusion (greater than 10 units/24 hr). All patients were followed clinically and by the blood bank for any signs of transfusion reactions or incompatibility throughout their hospital courses; none developed. There were no deaths related to transfusion incompatibility. We conclude that TOB used as an immediate resuscitative blood component is safe.(ABSTRACT TRUNCATED AT 250 WORDS)

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

    PubMed Central

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

    2017-01-01

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

  19. 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.

  20. Phthalate esters used as plasticizers in packed red blood cell storage bags may lead to progressive toxin exposure and the release of pro-inflammatory cytokines.

    PubMed

    Rael, Leonard T; Bar-Or, Raphael; Ambruso, Daniel R; Mains, Charles W; Slone, Denetta S; Craun, Michael L; Bar-Or, David

    2009-01-01

    Phthalate esters (PE's) are plasticizers used to soften PVC-based medical devices. PE's are the most abundant man-made pollutants and increase the risk of developing an allergic respiratory disease or a malignancy. The leaching of PE's in donated packed red blood cells (PRBC) during storage was assessed. PRBC transfusion bags containing CPD/AS-1 (ADSOL) buffer were analyzed. Samples were collected on storage day 1 and day 42. Two PE's, di-(2-ethylhexyl) phthalate (DEHP) and mono-(2-ethylhexyl) phthalate (MEHP), were measured by liquid chromatography coupled to mass spectrometry (LCMS). Interleukin-8 (IL-8) was measured by standard ELISA techniques. DEHP significantly increased from 34.3 microM (+/-20.0 SD) on day 1 to 433.2 microM (+/-131.2 SD) on day 42, a 12.6-fold increase. Similarly, MEHP significantly increased from 3.7 microM (+/-2.8 SD) on day 1 to 74.0 microM (+/-19.1 SD) on day 42, a 20.2-fold increase. Also, DEHP and MEHP increased the release of IL-8 from human umbilical vein endothelial cells (HUVEC). The transfusion of older units of PRBC could lead to an accumulation of PE's possibly resulting in inflammation and other effects. This accumulation could be exacerbated due to the decreased metabolism of PE's since trauma patients have a lower esterase activity, the enzymes responsible for metabolizing PE's. The effect of oxidative stress caused by PE's is discussed as a potential mechanism for increases in inflammation caused by older units of PRBC.

  1. Cell aggregation: Packing soft grains

    NASA Astrophysics Data System (ADS)

    Åström, J. A.; Karttunen, M.

    2006-06-01

    Cellular aggregates may be considered as collections of membrane enclosed units with a pressure difference between the internal and external liquid phases. Cells are kept together by membrane adhesion and/or confined space compression. Pattern formation and, in particular, intercellular spacing have important roles in controlling solvent diffusion within such aggregates. A physical approach is used to study generic aspects of cellular packings in a confined space. Average material properties are derived from the free energy. The appearance of penetrating intercellular void channels is found to be critically governed by the cell wall adhesion mechanisms during the formation of dense aggregates. A fully relaxed aggregate efficiently hinders solvent diffusion at high hydrostatic pressures, while a small fraction (˜0.1) of adhesion related packing frustration is sufficient for breaking such a blockage even at high a pressure.

  2. Modification of sodium, glucose, potassium, and osmolarity in packed red blood cells and fresh frozen plasma using a desktop hemoconcentrator setup.

    PubMed

    Striker, Carrie Whittaker; Woldorf, Stacia; Holt, David

    2012-06-01

    Massive transfusion with packed blood cells (PRBCs) or fresh frozen plasma (FFP) can result in dangerous complications including stroke, kidney failure, and cardiac arrest. A simple, bench top technique using a hemoconcentrator and dialysate solution is described to correct critical values of sodium, glucose, potassium, and osmolarity in PRBCs and FFP. Sodium, glucose, and osmolarity were corrected to normal or near normal values. Elevated potassium was reduced by 65%, but not completely normalized. A simple, bench top method for correcting dangerous abnormalities with PRBCs and FFP can be used to improve the safety of massive blood transfusion.

  3. Freeze-Dried Human Red Blood Cells

    DTIC Science & Technology

    1991-07-12

    starting cells are lost at rehydration). Hypotonic or hypertonic lysis of red cells can disrupt the normal asymmetric distribution of phospholipids between...remove the buffy coat and plasma. The packed RBC were washed in isotonic dextrose saline according to standard washing procedures (11] using an automated...cell washer ( Model 2991, COBE, Lakewood, CO). The washed and packed RBC (about 85% hematocrit) were resuspended to about 40% in hypertonic phosphate

  4. Red blood cell production

    MedlinePlus

    ... hemocytoblasts give rise to all of the formed elements in blood. If a hemocytoblast commits to becoming a cell called a proerythroblast, it will develop into a new red blood cell. The formation of a red ...

  5. Nitric oxide scavenging by red cell microparticles.

    PubMed

    Liu, Chen; Zhao, Weixin; Christ, George J; Gladwin, Mark T; Kim-Shapiro, Daniel B

    2013-12-01

    Red cell microparticles form during the storage of red blood cells and in diseases associated with red cell breakdown and asplenia, including hemolytic anemias such as sickle cell disease. These small phospholipid vesicles that are derived from red blood cells have been implicated in the pathogenesis of transfusion of aged stored blood and hemolytic diseases, via activation of the hemostatic system and effects on nitric oxide (NO) bioavailability. Red cell microparticles react with the important signaling molecule NO almost as fast as cell-free hemoglobin, about 1000 times faster than red-cell-encapsulated hemoglobin. The degree to which this fast reaction with NO by red cell microparticles influences NO bioavailability depends on several factors that are explored here. In the context of stored blood preserved in ADSOL, we find that both cell-free hemoglobin and red cell microparticles increase as a function of duration of storage, and the proportion of extra erythrocytic hemoglobin in the red cell microparticle fraction is about 20% throughout storage. Normalized by hemoglobin concentration, the NO-scavenging ability of cell-free hemoglobin is slightly higher than that of red cell microparticles as determined by a chemiluminescence NO-scavenging assay. Computational simulations show that the degree to which red cell microparticles scavenge NO will depend substantially on whether they enter the cell-free zone next to the endothelial cells. Single-microvessel myography experiments performed under laminar flow conditions demonstrate that microparticles significantly enter the cell-free zone and inhibit acetylcholine, endothelial-dependent, and NO-dependent vasodilation. Taken together, these data suggest that as little as 5 μM hemoglobin in red cell microparticles, an amount formed after the infusion of one unit of aged stored packed red blood cells, has the potential to reduce NO bioavailability and impair endothelial-dependent vasodilation.

  6. High Red Blood Cell Count

    MedlinePlus

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

  7. Red blood 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.

  8. Red blood cells, sickle cell (image)

    MedlinePlus

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

  9. Oxygen delivery from red cells.

    PubMed Central

    Clark, A; Federspiel, W J; Clark, P A; Cokelet, G R

    1985-01-01

    This paper deals with the theoretical analysis of the unloading of oxygen from a red cell. A scale analysis of the governing transport equations shows that the solutions have a boundary layer structure near the red-cell membrane. The boundary layer is a region of chemical nonequilibrium, and it owes its existence to the fact that the kinetic time scales are shorter than the diffusion time scales in the red cell. The presence of the boundary layer allows an analytical solution to be obtained by the method of matched asymptotic expansions. A very useful result from the analysis is a simple, lumped-parameter description of the oxygen delivery from a red cell. The accuracy of the lumped-parameter description has been verified by comparing its predictions with results obtained by numerical integration of the full equations for a one-dimensional slab. As an application, we calculate minimum oxygen unloading times for red cells. PMID:3978198

  10. Pediatric red cell disorders and pure red cell aplasia.

    PubMed

    Perkins, Sherrie L

    2004-12-01

    Anemia in children may arise from a wide variety of pathogenetic mechanisms that include congenital and acquired disorders. Often the diagnostic considerations include disorders that are not seen commonly in adults and lifelong disorders that arise in children and persist throughout life. Consideration of diverse causes of anemia such as red cell membrane disorders, red cell enzymopathies, congenital dyserythropoietic anemias, congenital sideroblastic anemias, and hereditary pure red cell aplasia (Diamond-Blackfan anemia), as well as infectious causes such as parvovirus B19 infection, often is required when diagnosing anemia in an infant or young child. Knowledge of these entities that are important causes of anemia in the pediatric population, including clinical manifestations and laboratory workup, will aid in recognition of the specific disease entities and effective workup of pediatric red cell disorders.

  11. 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 ...

  12. Red Blood Cell Antibody Identification

    MedlinePlus

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

  13. 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.

  14. Red Blood Cell Magnetophoresis

    PubMed Central

    Zborowski, Maciej; Ostera, Graciela R.; Moore, Lee R.; Milliron, Sarah; Chalmers, Jeffrey J.; Schechter, Alan N.

    2003-01-01

    The existence of unpaired electrons in the four heme groups of deoxy and methemoglobin (metHb) gives these species paramagnetic properties as contrasted to the diamagnetic character of oxyhemoglobin. Based on the measured magnetic moments of hemoglobin and its compounds, and on the relatively high hemoglobin concentration of human erythrocytes, we hypothesized that differential migration of these cells was possible if exposed to a high magnetic field. With the development of a new technology, cell tracking velocimetry, we were able to measure the migration velocity of deoxygenated and metHb-containing erythrocytes, exposed to a mean magnetic field of 1.40 T and a mean gradient of 0.131 T/mm, in a process we call cell magnetophoresis. Our results show a similar magnetophoretic mobility of 3.86 × 10−6 mm3 s/kg for erythrocytes with 100% deoxygenated hemoglobin and 3.66 × 10−6 mm3 s/kg for erythrocytes containing 100% metHb. Oxygenated erythrocytes had a magnetophoretic mobility of from −0.2 × 10−6 mm3 s/kg to +0.30 × 10−6 mm3 s/kg, indicating a significant diamagnetic component relative to the suspension medium, in agreement with previous studies on the hemoglobin magnetic susceptibility. Magnetophoresis may open up an approach to characterize and separate cells for biochemical analysis based on intrinsic and extrinsic magnetic properties of biological macromolecules. PMID:12668472

  15. Red blood cell magnetophoresis.

    PubMed

    Zborowski, Maciej; Ostera, Graciela R; Moore, Lee R; Milliron, Sarah; Chalmers, Jeffrey J; Schechter, Alan N

    2003-04-01

    The existence of unpaired electrons in the four heme groups of deoxy and methemoglobin (metHb) gives these species paramagnetic properties as contrasted to the diamagnetic character of oxyhemoglobin. Based on the measured magnetic moments of hemoglobin and its compounds, and on the relatively high hemoglobin concentration of human erythrocytes, we hypothesized that differential migration of these cells was possible if exposed to a high magnetic field. With the development of a new technology, cell tracking velocimetry, we were able to measure the migration velocity of deoxygenated and metHb-containing erythrocytes, exposed to a mean magnetic field of 1.40 T and a mean gradient of 0.131 T/mm, in a process we call cell magnetophoresis. Our results show a similar magnetophoretic mobility of 3.86 x 10(-6) mm(3) s/kg for erythrocytes with 100% deoxygenated hemoglobin and 3.66 x 10(-6) mm(3) s/kg for erythrocytes containing 100% metHb. Oxygenated erythrocytes had a magnetophoretic mobility of from -0.2 x 10(-6) mm(3) s/kg to +0.30 x 10(-6) mm(3) s/kg, indicating a significant diamagnetic component relative to the suspension medium, in agreement with previous studies on the hemoglobin magnetic susceptibility. Magnetophoresis may open up an approach to characterize and separate cells for biochemical analysis based on intrinsic and extrinsic magnetic properties of biological macromolecules.

  16. 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

  17. Red cell DAMPs and inflammation.

    PubMed

    Mendonça, Rafaela; Silveira, Angélica A A; Conran, Nicola

    2016-09-01

    Intravascular hemolysis, or the destruction of red blood cells in the circulation, can occur in numerous diseases, including the acquired hemolytic anemias, sickle cell disease and β-thalassemia, as well as during some transfusion reactions, preeclampsia and infections, such as those caused by malaria or Clostridium perfringens. Hemolysis results in the release of large quantities of red cell damage-associated molecular patterns (DAMPs) into the circulation, which, if not neutralized by innate protective mechanisms, have the potential to activate multiple inflammatory pathways. One of the major red cell DAMPs, heme, is able to activate converging inflammatory pathways, such as toll-like receptor signaling, neutrophil extracellular trap formation and inflammasome formation, suggesting that this DAMP both activates and amplifies inflammation. Other potent DAMPs that may be released by the erythrocytes upon their rupture include heat shock proteins (Hsp), such as Hsp70, interleukin-33 and Adenosine 5' triphosphate. As such, hemolysis represents a major inflammatory mechanism that potentially contributes to the clinical manifestations that have been associated with the hemolytic diseases, such as pulmonary hypertension and leg ulcers, and likely plays a role in specific complications of sickle cell disease such as endothelial activation, vaso-occlusive processes and tissue injury.

  18. 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.

  19. 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

  20. Prolonged red cell storage before transfusion increases extravascular hemolysis

    PubMed Central

    Rapido, Francesca; Brittenham, Gary M.; Bandyopadhyay, Sheila; La Carpia, Francesca; L’Acqua, Camilla; McMahon, Donald J.; Rebbaa, Abdelhadi; Wojczyk, Boguslaw S.; Netterwald, Jane; Wang, Hangli; Schwartz, Joseph; Eisenberger, Andrew; Soffing, Mark; Yeh, Randy; Divgi, Chaitanya; Ginzburg, Yelena Z.; Shaz, Beth H.; Sheth, Sujit; Francis, Richard O.; Spitalnik, Steven L.; Hod, Eldad A.

    2016-01-01

    BACKGROUND. Some countries have limited the maximum allowable storage duration for red cells to 5 weeks before transfusion. In the US, red blood cells can be stored for up to 6 weeks, but randomized trials have not assessed the effects of this final week of storage on clinical outcomes. METHODS. Sixty healthy adult volunteers were randomized to a single standard, autologous, leukoreduced, packed red cell transfusion after 1, 2, 3, 4, 5, or 6 weeks of storage (n = 10 per group). 51-Chromium posttransfusion red cell recovery studies were performed and laboratory parameters measured before and at defined times after transfusion. RESULTS. Extravascular hemolysis after transfusion progressively increased with increasing storage time (P < 0.001 for linear trend in the AUC of serum indirect bilirubin and iron levels). Longer storage duration was associated with decreasing posttransfusion red cell recovery (P = 0.002), decreasing elevations in hematocrit (P = 0.02), and increasing serum ferritin (P < 0.0001). After 6 weeks of refrigerated storage, transfusion was followed by increases in AUC for serum iron (P < 0.01), transferrin saturation (P < 0.001), and nontransferrin-bound iron (P < 0.001) as compared with transfusion after 1 to 5 weeks of storage. CONCLUSIONS. After 6 weeks of refrigerated storage, transfusion of autologous red cells to healthy human volunteers increased extravascular hemolysis, saturated serum transferrin, and produced circulating nontransferrin-bound iron. These outcomes, associated with increased risks of harm, provide evidence that the maximal allowable red cell storage duration should be reduced to the minimum sustainable by the blood supply, with 35 days as an attainable goal. REGISTRATION. ClinicalTrials.gov NCT02087514. FUNDING. NIH grant HL115557 and UL1 TR000040. PMID:27941245

  1. 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

  2. Red cell transfusion "trigger": a review.

    PubMed

    Petrides, Marian

    2003-07-01

    Despite the publication of several consensus guidelines that set forth recommendations for the transfusion of red cells, actual clinical practice continues to vary widely. Animal data and studies in human volunteers and patients support a red cell transfusion threshold of 7 to 8 g/dl in most patients. However, conflicting data, particularly in cardiac patients and in the elderly, suggest that it may be impossible to define a single red cell "trigger" for all patients. A well-designed, randomized, controlled trial is still needed to establish a safe threshold for red cell transfusion in adults with coronary artery disease.

  3. 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.

  4. Hyperkalemia After Packed Red Blood Cell Transfusion in Trauma Patients

    DTIC Science & Technology

    2008-02-01

    both adults and children, hypokalemia has been reported more frequently than hyperkalemia. The largest reported series of which we are aware...retrospective in nature, reported an incidence of hypokalemia of 72% in children undergoing liver transplantation; hyperkalemia occurred in less than 5% of...patients.1 Others have likewise observed hypokalemia to be more common after transfusion.2–4 In the few, small studies describing hyperkalemia after

  5. 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.

  6. 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...

  7. 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...

  8. 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...

  9. 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...

  10. 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...

  11. Uptake of carnitine by red blood cells

    SciTech Connect

    Campa, M.; Borum, P.

    1986-05-01

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

  12. 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

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

    PubMed

    Mohandas, Narla; Gallagher, Patrick G

    2008-11-15

    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.

  14. Human spleen and red blood cells

    NASA Astrophysics Data System (ADS)

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

    2016-11-01

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

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

    PubMed

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

    2014-07-01

    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.

  16. Malaria and human red blood cells.

    PubMed

    Mohandas, Narla; An, Xiuli

    2012-11-01

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

  17. Autoimmune Lymphoproliferative Syndrome with Red Cell Aplasia.

    PubMed

    Meena, K R; Bisht, Supriya; Tamaria, K C

    2015-12-01

    Autoimmune Lymphoproliferative Syndrome (ALPS) is a rare inherited disorder of abnormal lymphocyte apoptosis, leading to chronic lymphoproliferation. It presents as lymphadenopathy, hepatosplenomegaly and autoimmune phenomena. Pure red cell aplasia is characterized by normochromic normocytic anemia, reticulocytopenia, and absence of erythroblasts from a normal bone marrow. Only few lymphoproliferative disorders have been associated with erythroid aplasia. The authors are reporting a case of ALPS associated with red cell aplasia in a 7-y-old girl.

  18. Diphenylhydantoin-induced pure red cell aplasia.

    PubMed

    Rusia, Usha; Malhotra, Purnima; Joshi, Panul

    2006-01-01

    Pure red cell aplasia is an uncommon complication of diphenylhydantoin therapy. It has not been reported in Indian literature. Awareness of the entity helps in establishing the cause of anaemia in these patients and alerts the physicians to the need of comprehensive haematological monitoring in these patients. A case of 58-year-old male who developed pure red cell aplasia following three months of diphenylhydantoin therapy is reported here.

  19. 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.

  20. Genomic Typing of Red Cell Antigens

    DTIC Science & Technology

    2011-09-01

    Antigen‐Matched  Red  Cells   for  Sickle   Cell   Anemia  Patients  Using  Molecular Typing to Augment Testing: Meghan Delaney, Prashant Gaur, Askale...H, Constans J, Quilici JC, Lefevre‐Witier P, Sevin J, Stevens M: Study of red blood  cell  and serum enzymes in  five  Pyrenean communities and in a...Antigen‐Matched Red  Cells  for  Sickle   Cell  Anemia Patients  Using Molecular Typing to Augment Testing: AABB (poster) 2009.  Background: Patients with  sickle

  1. 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

  2. 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...

  3. 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...

  4. 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...

  5. 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...

  6. 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...

  7. 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...

  8. 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...

  9. 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...

  10. 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...

  11. 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...

  12. 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

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

    PubMed

    Murata, T

    1983-01-01

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

  14. 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.

  15. 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

  16. Storage Lesion. Role of Red Cell Breakdown

    PubMed Central

    Kim-Shapiro, Daniel B.; Lee, Janet; Gladwin, Mark T.

    2011-01-01

    As stored blood ages intraerythrocytic energy sources are depleted resulting in reduced structural integrity of the membrane. Thus, stored red cells become less deformable and more fragile as they age. This fragility leads to release of cell-free hemoglobin and formation of microparticles, sub-micron hemoglobin-containing vesicles. Upon transfusion, it is likely that additional hemolysis and microparticle formation occurs due to breakdown of fragile red blood cells. Release of cell-free hemoglobin and microparticles leads to increased consumption of nitric oxide (NO), an important signaling molecule that modulates blood flow, and may promote inflammation. Stored blood may also be deficient in recently discovered blood nitric oxide synthase activity. We hypothesize that these factors play a potential role in the blood storage lesion. PMID:21496045

  17. Freeze-Dried Human Red Blood Cells

    DTIC Science & Technology

    1992-04-15

    freeze-dried and rehydrated blood cells will be made radioactive with " chromium and infused into my other arm through a hypodermic needle . No more than...directed at: (1) development of buffer formulations based on the glass transition and water replacement theory : (2) establishing standard...survival of transfused red blood cells. The labelled RBC were infused through a 20 gauge needle into the volunteer via a scalp vein in the right arm

  18. Interferometric phase microscopy of red blood cells

    NASA Astrophysics Data System (ADS)

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

    2013-12-01

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

  19. 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...

  20. 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...

  1. 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...

  2. 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...

  3. 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...

  4. 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...

  5. 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...

  6. 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...

  7. 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...

  8. 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...

  9. 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...

  10. 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...

  11. 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...

  12. 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...

  13. 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...

  14. Red cell distribution width and cancer

    PubMed Central

    Danese, Elisa

    2016-01-01

    Red cell distribution width (RDW) is an index which primarily reflects impaired erythropoiesis and abnormal red blood cell survival. In last years the interest in this marker has considerably grown and now a lot of data are available indicating that this simple and inexpensive parameter is a strong and independent risk factor for death in the general population. Moreover, several investigations have been performed to investigate the role of RDW in cardiovascular and thrombotic disorders. Contrarily, there are relatively few reports focusing on RDW in the area of oncology and to date none review have been performed in this specific field. As such, the aim of this narrative review is to summarize some interesting results obtained in studies performed in patients affected by solid and hematological tumors. Even if larger studies are needed before these preliminary findings can be generalized, it seems plausible to affirm that RDW can be useful by adding prognostic information in patients with oncologic disease. PMID:27867951

  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. 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.”

  17. 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.

  18. Reversibility of red blood cell deformation.

    PubMed

    Zeitz, Maria; Sens, P

    2012-05-01

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

  19. Glycolate kinase activity in human red cells.

    PubMed

    Fujii, S; Beutler, E

    1985-02-01

    Human red cells manifest glycolate kinase activity. This activity copurifies with pyruvate kinase and is decreased in the red cells of subjects with hereditary pyruvate kinase deficiency. Glycolate kinase activity was detected in the presence of FDP or glucose-1,6-P2. In the presence of 1 mmol/L FDP, the Km for adenosine triphosphate (ATP) was 0.28 mmol/L and a half maximum velocity for glycolate was obtained at 40 mmol/L. The pH optimum of the reaction was over 10.5 With 10 mumol/L FDP, 500 mumol/L glucose-1,6-P2, 2 mmol/L ATP, 5 mmol/L MgCl2, and 50 mmol/L glycolate at pH 7.5, glycolate kinase activity was calculated to be approximately 0.0013 U/mL RBC. In view of this low activity even in the presence of massive amounts of glycolate, the glycolate kinase reaction cannot account for the maintenance of the reported phosphoglycolate level in human red cells.

  20. Red blood cell transfusion in newborn infants

    PubMed Central

    Whyte, Robin K; Jefferies, Ann L

    2014-01-01

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

  1. 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.

  2. 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.

  3. Osmotic water permeability of human red cells

    PubMed Central

    1981-01-01

    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. PMID:7229611

  4. 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

  5. Red cell damage after pumping by two infusion control devices (Arcomed VP 7000 and IVAC 572).

    PubMed

    Parfitt, H S; Davies, S V; Tighe, P; Ewings, P

    2007-08-01

    The aim of this study was to assess the performance in terms of red cell damage of two peristaltic volumetric infusion pumps - the Alaris IVAC 572 (San Diego, CA, USA) and Arcomed Volumed VP7000 (Regensdorf, Switzerland). Various infusion pumps are available to transfuse blood at a predetermined rate. It is recommended that each machine should be individually assessed. This experiment used six units of single-donor-transfusable packed red cells and ran each unit through both pumps. This was carried out at 9, 28 and 35 days post-donation at rates from 2 to 150 mL h(-1). Post-pumping samples from these experiments, and a pre-pumping sample in each case, were analysed for levels of potassium and free haemoglobin (Hb). They were also examined microscopically for evidence of cell damage. Potassium levels showed no significant change with pumping on any occasion, but rose significantly as the samples aged. Free Hb showed some variation, but the only consistent finding was a similar rise in value with increasing pack age. Microscopic examination revealed no cell damage under any condition. Both pumps performed to an acceptable level and appear safe to be used for red cell transfusion.

  6. 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.

  7. 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

    2006-03-05

    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.

  8. 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.

  9. Argon laser radiation of human clots: differential photoabsorption in red cell rich and red cell poor clots

    SciTech Connect

    Lee, G.; Chan, M.C.; Seckinger, D.L.; Vazquez, A.; Rosenthal, P.K.; Lee, K.K.; Ikeda, R.M.; Reis, R.L.; Hanna, E.S.; Mason, D.T.

    1985-06-01

    Since argon laser radiation (454-514 nm) can vaporize human clots, the authors determined whether the absorption of laser energies can differ among different types of blood clots. Thus, they performed spectrophotometric studies and examined the ability of this laser to penetrate red cell rich and red cell poor clots. Fifty-four red cell rich and red cell poor clot samples, varying in depth from 1.8 to 5.0 mm, were subjected to 3, 5 and 7 watts from an argon laser beam. At a given power intensity, the deeper the red cell rich clot, the longer was the time needed to penetrate the clot. The higher the power used, the shorter was the red clot penetration time. In contrast, all power levels used up to 5 minutes did not penetrate any of the varying depths of red cell poor clots. Spectrophotometrically, the red cell rich clot had an absorption curve typical of hemoglobin pigment while the red cell poor clot, in the absence of hemoglobin, had poor absorption between 350 and 600 nm and was unable to absorb argon laser energies. Thus, the argon laser provides a therapeutic modality for human red cell rich clot dissolution but the present approach does not appear to be effective against red cell poor clots.

  10. 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.

  11. 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.

  12. A simple technique for red blood cell removal in major ABO-incompatible bone marrow transplantation.

    PubMed

    Mayer, G; Wernet, D; Northoff, H; Schneider, W

    1994-01-01

    A simple technique for red blood cell (RBC) removal in major ABO-incompatible bone marrow transplantation is reported requiring two centrifugation steps, special blood bags and a mechanical device to separate the buffy coat from RBCs within the bag. In 42 transplantations an average of 84% of nucleated cells was recovered with an average contamination of 7.5 ml packed RBCs. The preparations were well tolerated in all patients whose isoagglutinin titers had not been reduced. Bone marrow engraftment was not significantly different from control groups.

  13. Image analysis of nucleated red blood cells.

    PubMed

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

    1983-08-01

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

  14. Hereditary spherocytosis, elliptocytosis, and other red cell membrane disorders.

    PubMed

    Da Costa, Lydie; Galimand, Julie; Fenneteau, Odile; Mohandas, Narla

    2013-07-01

    Hereditary spherocytosis and elliptocytosis are the two most common inherited red cell membrane disorders resulting from mutations in genes encoding various red cell membrane and skeletal proteins. Red cell membrane, a composite structure composed of lipid bilayer linked to spectrin-based membrane skeleton is responsible for the unique features of flexibility and mechanical stability of the cell. Defects in various proteins involved in linking the lipid bilayer to membrane skeleton result in loss in membrane cohesion leading to surface area loss and hereditary spherocytosis while defects in proteins involved in lateral interactions of the spectrin-based skeleton lead to decreased mechanical stability, membrane fragmentation and hereditary elliptocytosis. The disease severity is primarily dependent on the extent of membrane surface area loss. Both these diseases can be readily diagnosed by various laboratory approaches that include red blood cell cytology, flow cytometry, ektacytometry, electrophoresis of the red cell membrane proteins, and mutational analysis of gene encoding red cell membrane proteins.

  15. 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.

  16. 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.

  17. 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

  18. Functions of red cell surface proteins.

    PubMed

    Daniels, G

    2007-11-01

    The external membrane of the red cell contains numerous proteins that either cross the lipid bilayer one or more times or are anchored to it through a lipid tail. Many of these proteins express blood group activity. The functions of some of these proteins are known; in others their function can only be surmised from the protein structure or from limited experimental evidence. They are loosely divided into four categories based on their functions: membrane transporters; adhesion molecules and receptors; enzymes; and structural proteins that link the membrane with the membrane skeleton. Some of the proteins carry out more than one of these functions. Some proteins may complete their major functions during erythropoiesis or may only be important under adverse physiological conditions. Furthermore, some might be evolutionary relics and may no longer have significant functions. Polymorphisms or rare changes in red cell surface proteins are often responsible for blood groups. The biological significance of these polymorphisms or the selective pressures responsible for their stability within populations are mostly not known, although exploitation of the proteins by pathogenic micro-organisms has probably played a major role.

  19. 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.

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

    PubMed Central

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

    2015-01-01

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

  1. Microconfined flow behavior of red blood cells.

    PubMed

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

    2016-01-01

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

  2. Ektacytometry: Instrumentation and Applications in Red Blood Cell Preservation Studies.

    DTIC Science & Technology

    1982-05-10

    that it was necessary to maintain an isotonic environment, since the red blood cells respond differently to shear stress under hypertonic or...the red blood cells respond differently to shear stress under hypertonic or hypotonic conditions. The most unexpected observation was an absence of...required to compare samples analyzed the same day. 2. Treatment of Human Red Blood Cells With Hypotonic and Hypertonic Solutions and Glutaraldehyde

  3. Rules of tissue packing involving different cell types: human muscle organization

    PubMed Central

    Sánchez-Gutiérrez, Daniel; Sáez, Aurora; Gómez-Gálvez, Pedro; Paradas, Carmen; Escudero, Luis M.

    2017-01-01

    Natural packed tissues are assembled as tessellations of polygonal cells. These include skeletal muscles and epithelial sheets. Skeletal muscles appear as a mosaic composed of two different types of cells: the “slow” and “fast” fibres. Their relative distribution is important for the muscle function but little is known about how the fibre arrangement is established and maintained. In this work we capture the organizational pattern in two different healthy muscles: biceps brachii and quadriceps. Here we show that the biceps brachii muscle presents a particular arrangement, based on the different sizes of slow and fast fibres. By contrast, in the quadriceps muscle an unbiased distribution exists. Our results indicate that the relative size of each cellular type imposes an intrinsic organization into natural tessellations. These findings establish a new framework for the analysis of any packed tissue where two or more cell types exist. PMID:28071729

  4. Rules of tissue packing involving different cell types: human muscle organization.

    PubMed

    Sánchez-Gutiérrez, Daniel; Sáez, Aurora; Gómez-Gálvez, Pedro; Paradas, Carmen; Escudero, Luis M

    2017-01-10

    Natural packed tissues are assembled as tessellations of polygonal cells. These include skeletal muscles and epithelial sheets. Skeletal muscles appear as a mosaic composed of two different types of cells: the "slow" and "fast" fibres. Their relative distribution is important for the muscle function but little is known about how the fibre arrangement is established and maintained. In this work we capture the organizational pattern in two different healthy muscles: biceps brachii and quadriceps. Here we show that the biceps brachii muscle presents a particular arrangement, based on the different sizes of slow and fast fibres. By contrast, in the quadriceps muscle an unbiased distribution exists. Our results indicate that the relative size of each cellular type imposes an intrinsic organization into natural tessellations. These findings establish a new framework for the analysis of any packed tissue where two or more cell types exist.

  5. Optical analysis of red blood cell suspension

    NASA Astrophysics Data System (ADS)

    Szołna, Alicja A.; Grzegorzewski, Bronisław

    2008-12-01

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

  6. Fluorometric assay for red blood cell antibodies

    SciTech Connect

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

    1981-03-01

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

  7. 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.

  8. Square cell packing in the Drosophila embryo through spatiotemporally regulated EGF receptor signaling

    PubMed Central

    Tamada, Masako; Zallen, Jennifer A.

    2015-01-01

    Summary Cells display dynamic and diverse morphologies during development, but the strategies by which differentiated tissues achieve precise shapes and patterns are not well understood. Here we identify a developmental program that generates a highly ordered square cell grid in the Drosophila embryo through sequential and spatially regulated cell alignment, oriented cell division, and apicobasal cell elongation. The basic leucine zipper transcriptional regulator Cnc is necessary and sufficient to produce a square cell grid in the presence of a midline signal provided by the EGF receptor ligand, Spitz. Spitz orients cell divisions through a Pins/LGN-dependent spindle positioning mechanism and controls cell shape and alignment through a transcriptional pathway that requires the Pointed ETS domain protein. These results identify a strategy for producing ordered square cell packing configurations in epithelia and reveal a molecular mechanism by which organized tissue structure is generated through spatiotemporally regulated responses to EGF receptor activation. PMID:26506305

  9. Mechanisms of immune red cell destruction, and red cell compatibility testing

    SciTech Connect

    Garratty, G.

    1983-03-01

    The immune destruction of red cells can occur as a complement-mediated intravascular process, or extravascularly, where the red cells are destroyed by macrophages following interaction with cell-bound IgG1, IgG3, and/or C3b. Many of the factors that affect this in vivo destruction are not taken into account during in vitro pretransfusion compatibility testing. At present, even by use of more elaborate tests, it is difficult to accurately predict the fate of a transfused unit of blood. By using some simple information, such as antibody specificity and thermal range, it is sometimes possible to predict the outcome of transfusing a unit of blood that is incompatible in vitro. At other times it may be necessary to utilize /sup 51/Cr-labeled red cells to determine the risk of transfusing such units. Because of the paucity of reported clinical correlations, macrophage/monocyte monolayer assays are of little practical value at present.

  10. 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.

  11. Growth and replication of red rain cells at 121°C and their red fluorescence

    NASA Astrophysics Data System (ADS)

    Gangappa, Rajkumar; Wickramasinghe, Chandra; Wainwright, Milton; Kumar, A. Santhosh; Louis, Godfrey

    2010-09-01

    We have shown that the red cells found in the Red Rain (which fell on Kerala, India, in 2001) survive and grow after incubation for periods of up to two hours at 121°C . Under these conditions daughter cells appear within the original mother cells and the number of cells in the samples increases with length of exposure to 121°C. No such increase in cells occurs at room temperature, suggesting that the increase in daughter cells is brought about by exposure of the Red Rain cells to high temperatures. This is an independent confirmation of results reported earlier by two of the present authors, claiming that the cells can replicate under high pressure at temperatures upto 300°C. The flourescence behaviour of the red cells is shown to be in remarkable correspondence with the extended red emission observed in the Red Rectagle planetary nebula and other galactic and extragalactic dust clouds, suggesting, though not proving an extraterrestrial origin.

  12. 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.

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

    PubMed

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

    2016-11-04

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

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

    PubMed

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

    1997-09-01

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

  15. 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.

  16. Efflux of red cell water into buffered hypertonic solutions.

    PubMed

    OLMSTEAD, E G

    1960-03-01

    Buffered NaCl solutions hypertonic to rabbit serum were prepared and freezing point depressions of each determined after dilution with measured amounts of water. Freezing point depression of these dilutions was a linear function of the amount of water added. One ml. of rabbit red cells was added to each 4 ml. of the hypertonic solutions and after incubation at 38 degrees C. for 30 minutes the mixture was centrifuged and a freezing point depression determined on the supernatant fluid. The amount of water added to the hypertonic solutions by the red cells was calcuated from this freezing point depression. For each decrease in the freezing point of -0.093 degrees C. of the surrounding solution red cells gave up approximately 5 ml. of water per 100 ml. of red cells in the range of -0.560 to -0.930 degrees C. Beyond -0.930 degrees C. the amount of water given up by 100 ml. of red cells fits best a parabolic equation. The maximum of this equation occurred at a freezing point of the hypertonic solution of -2.001 degrees C. at which time the maximum amount of water leaving the red cells would be 39.9 ml. per 100 ml. of red cells. The data suggest that only about 43 per cent of the red cell water is available for exchange into solutions of increasing tonicity.

  17. 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

  18. Red blood cell vesiculation in hereditary hemolytic anemia.

    PubMed

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

    2013-12-13

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

  19. 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

  20. Red blood cell transfusion in clinical practice.

    PubMed

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

    2007-08-04

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

  1. Hemodynamic effects of red blood cell aggregation.

    PubMed

    Baskurt, Oguz K; Meiselman, Herbert J

    2007-01-01

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

  2. Understanding red blood cell alloimmunization triggers.

    PubMed

    Hendrickson, Jeanne E; Tormey, Christopher A

    2016-12-02

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

  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. Electricity generation and microbial community changes in microbial fuel cells packed with different anodic materials.

    PubMed

    Sun, Yanmei; Wei, Jincheng; Liang, Peng; Huang, Xia

    2011-12-01

    Four materials, carbon felt cube (CFC), granular graphite (GG), granular activated carbon (GAC) and granular semicoke (GS) were tested as packed anodic materials to seek a potentially practical material for microbial fuel cells (MFCs). The microbial community and its correlation with the electricity generation performance of MFCs were explored. The maximum power density was found in GAC, followed by CFC, GG and GS. In GAC and CFC packed MFCs, Geobacter was the dominating genus, while Azospira was the most populous group in GG. Results further indicated that GAC was the most favorable for Geobacter adherence and growth, and the maximum power densities had positive correlation with the total biomass and the relative abundance of Geobacter, but without apparent correlation with the microbial diversity. Due to the low content of Geobacter in GS, power generated in this system may be attributed to other microorganisms such as Synergistes, Bacteroidetes and Castellaniella.

  5. COMPARISON OF OUTCOMES BETWEEN BLOOD GROUP O AND NON-GROUP O PREMATURE NEONATES RECEIVING RED CELL TRANSFUSIONS

    PubMed Central

    Boral, Leonard I.; Staubach, Zane G.; de Leeuw, Reny; MacIvor, Duncan C.; Kryscio, Richard; Bada, Henrietta S.

    2015-01-01

    Background At some institutions all babies requiring red blood cell (RBC) transfusions in neonatal intensive care units (NICUs) receive group O RBCs. Although transfused O plasma is minimized in packed RBCs, small amounts of residual anti-A, anti-B and anti-A, B in group O packed RBCs may bind to the corresponding A and B antigens of non-group O RBCs, possibly hemolyzing their native RBCs and thereby releasing free hemoglobin theoretically resulting in hypercoagulability and promoting bacterial growth from free iron. Study Design and Methods Transfused group O and non- group O premature infants in the University of Kentucky Children’s Hospital NICU database were compared for a number of severity markers to determine if transfused non-group O patients had worse outcomes than those of group O. Results 724 neonates in this sample of NICU babies received at least one blood component. There were no significant differences between group O and non-group O babies with regard to final disposition or complications. Conclusions This reassuring finding validates the longstanding neonatal transfusion practice of using group O packed red cells for NICU babies of all blood groups. However, because a recent study shows increased mortality from NEC in AB neonates receiving only group O RBC and suggests a change in neonatal transfusion practice to ABO group specific red cells, more studies may be warranted PMID:24225743

  6. Photochemical decontamination of red cell concentrates with the silicon phthalocyanine Pc 4 and red light

    NASA Astrophysics Data System (ADS)

    Ben-Hur, Ehud; Zuk, Maria M.; Oetjen, Joyce; Chan, Wai-Shun; Lenny, Leslie; Horowitz, Bernard

    1999-07-01

    Virus inactivation in red blood cells concentrates (RBCC) is being studied in order to increase the safety of the blood supply. For this purpose we have been studying the silicon phthalocyanine (Pc 4), a photosensitizer activated with red light. Two approaches were used to achieve enhanced selectivity of Pc 4 for virus inactivation. One was formulation of Pc 4 in liposomes that reduce its binding to red cells. The other was the use of a light emitting diode (LED) array emitting at 700 nm. Vesicular stomatitis virus (VSV) infectivity served as an endpoint for virus kill in treated RBCC. Red cell hemolysis and circulatory survival in rabbits served as measures for red cell damage. Treatment of small aliquots of human RBCC with 2 (mu) M Pc 4 in liposomes and 10 J/cm2 of 700 nm LED light in the presence of the quenches of reactive oxygen species glutathione and trolox resulted in 6 log10 inactivation of VSV. Under these conditions hemolysis of treated red cells stored at 4 degree(s)C for 21 days was only slightly above that of control cells. Rabbit RBCC similarly treated circulated with a half life of 7.5 days compared with 10.5 days of control. It is concluded that Pc 4 used as described here may be useful for viral decontamination of RBCC, pending toxicological and clinical studies.

  7. 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.

  8. Light scattering by aggregated red blood cells

    NASA Astrophysics Data System (ADS)

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

    2002-03-01

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

  9. Association between anemia and packed cell transfusion and outcomes of ventricular septal defect and atrioventricular canal repair in children.

    PubMed

    Khan, Zeeshan; Natarajan, Girija; Sallaam, Salaam; Bondarenko, Igor; Walters, Henry L; Delius, Ralph; Aggarwal, Sanjeev

    2014-03-01

    Data on the prevalence and impact of anemia and packed red blood cell (PRBC) transfusions in children with congenital heart disease are limited. Our objectives were to determine the prevalence of anemia and its impact and the impact of PRBC transfusion in the initial 5 days after surgical repair on postoperative outcomes in infants with ventricular septal defect (VSD) and atrioventricular (AV) canal. Retrospective chart review of infants (1 year old) (n = 195) with AV canal or VSD who underwent surgical repair at Children's Hospital of Michigan during a 10-year period. Statistical analyses (SPSS 17.0) included Chi square and Student t test as well as regression analysis with significance set at p = 0.05. Preoperative anemia was diagnosed in 45 of 195 (23%) children. Anemic infants had VSD more frequently (80%), significantly shorter bypass and cross-clamp durations, and higher red cell distribution widths. Postoperative outcomes and PRBC transfusions were similar in the groups. On regression analysis, AV canal was associated with a significantly lower (odds ratio 0.21; 95% confidence interval 0.07-0.68, p = 0.009) risk of anemia. Infants who received a PRBC transfusion (n = 42) had significantly lower birth weights as well as weights at surgery and longer postoperative durations of pressor use, ventilation, oxygen supplementation, and length of stay than those who did not (n = 153) receive transfusions. PRBC transfusion was independently associated with longer postoperative length of stay, oxygen, pressor use, and ventilator duration. Approximately 23% of infants with AV canal or VSD are anemic. PRBC transfusions in the initial 5 postoperative days, but not anemia, are independently associated with adverse postoperative outcomes. Further studies to evaluate conservative transfusion strategies in this population are needed.

  10. Electrochemical removal of nitrate using ZVI packed bed bipolar electrolytic cell.

    PubMed

    Jeong, Joo-Young; Kim, Han-Ki; Kim, Jung-Hwan; Park, Joo-Yang

    2012-09-01

    The present study investigates the performance of the zero valent iron (ZVI, Fe(0)) packed bed bipolar electrolytic cell for nitrate removal. The packing mixture consists of ZVI as electronically conducting material and silica sand as non-conducting material between main cathode and anode electrodes. In the continuous column experiments for the simulated groundwater (initial nitrate and electrical conductivity of about 30 mg L(-1) as N and 300 μS cm(-1), respectively), above 99% of nitrate was removed at the applied potential of 600 V with the main anode placed on the bottom of reactor. The influx nitrate was converted to ammonia (20% to maximum 60%) and nitrite (always less than 0.5 mg L(-1) as N in the effluent). The optimum packing ratio (v/v) of silica sand to ZVI was found to be 1:1-2:1. Magnetite was observed on the surface of the used ZVI as corrosion product. The reduction at the lower part of the reactor in acidic condition and adsorption at the upper part of the reactor in alkaline condition are the major mechanism of nitrate removal.

  11. 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)

  12. 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.

  13. Red cell exchange: special focus on sickle cell disease.

    PubMed

    Kim, Haewon C

    2014-12-05

    The primary function of red blood cells (RBCs) is to deliver oxygen from the lungs to tissues. Tissue hypoxia occurs when the oxygen-carrying capacity of RBCs is compromised due primarily to 3 causes: (1) a reduction in circulating RBC mass, (2) an increase in circulating RBC mass, or (3) abnormal hemoglobin (Hb) that either does not sufficiently release oxygen to tissues (high-oxygen-affinity hemoglobin) or occludes the microvasculature due to deformed RBCs (sickled RBCs). To improve oxygenation in patients with reduced or increased RBC mass, RBC administration (simple transfusion) or RBC removal (RBC depletion) is performed, respectively. However, for patients with abnormal Hb, RBCs containing abnormal Hb are removed and replaced by healthy volunteer donor RBCs by red cell exchange (RCE). RCE can be performed by manual exchange or by automated exchange using a blood cell separator (erythrocytapheresis). In this review, indications for RCE in sickle cell disease using the evidence-based American Society for Apheresis categories(1) are presented and the rationale for RCE in each disorder are discussed. Simple transfusion versus RCE and manual RCE versus automated RCE are compared. Finally, this review briefly presents some of the challenges of performing erythrocytapheresis in small children and discusses various choices for central venous access during RCE.(2.)

  14. 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

  15. 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.

  16. 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.

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

    PubMed Central

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

    2009-01-01

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

  18. 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.

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

    PubMed

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

    2006-01-01

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

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

    PubMed

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

    2011-10-01

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

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

    SciTech Connect

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

    1988-05-01

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

  2. 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.

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

    NASA Astrophysics Data System (ADS)

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

    2013-01-01

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

  4. 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.

  5. Modelling the structure of the red cell membrane.

    PubMed

    Burton, Nicholas M; Bruce, Lesley J

    2011-04-01

    The red cell membrane has long been the focus of extensive study. The macromolecules embedded within the membrane carry the blood group antigens and perform many functions including the vital task of gas exchange. Links between the intramembrane macromolecules and the underlying cytoskeleton stabilize the biconcave morphology of the red cell and allow deformation during microvascular transit. Much is now known about the proteins of the red cell membrane and how they are organised. In many cases we have an understanding of which proteins are expressed, the number of each protein per cell, their oligomeric state(s), and how they are collected in large multi-protein complexes. However, our typical view of these structures is as cartoon shapes in schematic figures. In this study we have combined knowledge of the red cell membrane with a wealth of protein structure data from crystallography, NMR, and homology modelling to generate the first, tentative models of the complexes which link the membrane to the cytoskeleton. Measurement of the size of these complexes and comparison with known cytoskeletal distance parameters suggests the idea of interaction between the membrane complexes, which may have profound implications for understanding red cell function and deformation.

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

    PubMed

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

    2011-10-01

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

  7. 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...

  8. 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...

  9. 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...

  10. Mechanisms Linking Red Blood Cell Disorders and Cardiovascular Diseases

    PubMed Central

    2015-01-01

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

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

    PubMed

    Mozos, Ioana

    2015-01-01

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

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

    PubMed

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

    2017-02-01

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

  13. Semantic Extension of Agent-Based Control: The Packing Cell Case Study

    NASA Astrophysics Data System (ADS)

    Vrba, Pavel; Radakovič, Miloslav; Obitko, Marek; Mařík, Vladimír

    The paper reports on the latest R&D activities in the field of agent-based manufacturing control systems. It is documented that this area becomes strongly influenced by the advancements of semantic technologies like the Web Ontology Language. The application of ontologies provides the agents with much more effective means for handling, exchanging and reasoning about the knowledge. The ontology dedicated for semantic description of orders, production processes and material handling tasks in discrete manufacturing domain has been developed. In addition, the framework for integration of this ontology in distributed, agent-based control solutions is given. The Manufacturing Agent Simulation Tool (MAST) is used as a base for pilot implementation of the ontology-powered multiagent control system; the packing cell environment is selected as a case study.

  14. In vivo red cell destruction by anti-Lu6

    SciTech Connect

    Issitt, P.D.; Valinsky, J.E.; Marsh, W.L.; DiNapoli, J.; Gutgsell, N.S. )

    1990-03-01

    An example is presented of an IgG1, anti-Lu6, that reacted by indirect antiglobulin test and was capable of destroying antigen-positive red cells in vivo. Two methods for the measurement of red cell survival, {sup 51}Cr labeling and flow cytometry, gave the same result: 20 percent of the test dose of Lu:6 red cells was destroyed in the first hour after injection and 80 percent in the first 24 hours. The clinical relevance of the antibody was correctly predicted by an in vitro monocyte monolayer assay. The finding that this example of anti-Lu6 was clinically significant should not be taken to mean that all antibodies directed against high-incidence Lutheran and Lutheran system-related antigens will behave similarly. When such antibodies are encountered, in vivo and/or in vitro studies to assess their clinical significance are necessary before rare blood is used for transfusion.

  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. Cytosolic protein concentration is the primary volume signal in dog red cells

    PubMed Central

    1991-01-01

    It is not known whether the activation of Na/H exchange by shrinkage in dog red cells is due to the packing of cell contents or a change in cell configuration. To make this distinction we prepared resealed ghosts that resembled intact cells in hemoglobin concentration and surface area, but had one-third their volume. A shrinkage-induced, amiloride-sensitive Na flux in the ghosts was activated at a much smaller volume in the ghosts than in the intact cells, but at the same concentration (by weight) of dry solids in both preparations. Na/H exchange in ghosts containing a mixture of 40% albumin and 60% hemoglobin (weight/weight) was activated by osmotic shrinkage at a dry solid concentration similar to that of intact cells or of ghosts containing only hemoglobin. We conclude that the process of Na/H exchange activation by cell shrinkage originates with an increase in the concentration of intracellular protein and not with a change in membrane configuration or tension. The macromolecular crowding that accompanies the reduction in cell volume probably alters the activities of key enzymes that in turn modulate the Na/H exchanger. PMID:1662684

  17. Electronically configured battery pack

    SciTech Connect

    Kemper, D.

    1997-03-01

    Battery packs for portable equipment must sometimes accommodate conflicting requirements to meet application needs. An electronically configurable battery pack was developed to support two highly different operating modes, one requiring very low power consumption at a low voltage and the other requiring high power consumption at a higher voltage. The configurable battery pack optimizes the lifetime and performance of the system by making the best use of all available energy thus enabling the system to meet its goals of operation, volume, and lifetime. This paper describes the cell chemistry chosen, the battery pack electronics, and tradeoffs made during the evolution of its design.

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

    PubMed

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

    2015-06-01

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

  19. 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.

  20. Enhanced harvesting of red photons in nanowire solar cells: evidence of resonance energy transfer.

    PubMed

    Shankar, Karthik; Feng, Xinjian; Grimes, Craig A

    2009-04-28

    Modern excitonic solar cells efficiently harvest photons in the 350-650 nm spectral range; however, device efficiencies are typically limited by poor quantum yields for red and near-infrared photons. Using Forster-type resonance energy transfer from zinc phthalocyanine donor molecules to ruthenium polypyridine complex acceptors, we demonstrate a four-fold increase in quantum yields for red photons in dye-sensitized nanowire array solar cells. The dissolved donor and surface anchored acceptor molecules are not tethered to each other, through either a direct chemical bond or a covalent linker layer. The spatial confinement of the electrolyte imposed by the wire-to-wire spacing of the close-packed nanowire array architecture ensures that the distances between a significant fraction of donors and acceptors are within a Förster radius. The critical distance for energy transfer from an isolated donor chromophore to a self-assembled monolayer of acceptors on a plane follows the inverse fourth power instead of the inverse sixth power relation. Consequently, we observe near quantitative energy transfer efficiencies in our devices. Our results represent a new design paradigm in excitonic solar cells and show it is possible to more closely match the spectral response of the device to the AM 1.5 solar spectrum through use of electronic energy transfer.

  1. Battery Pack Life Estimation through Cell Degradation Data and Pack Thermal Modeling for BAS+ Li-Ion Batteries. Cooperative Research and Development Final Report, CRADA Number CRD-12-489

    SciTech Connect

    Smith, Kandler

    2016-01-21

    Battery Life estimation is one of the key inputs required for Hybrid applications for all GM Hybrid/EV/EREV/PHEV programs. For each Hybrid vehicle program, GM has instituted multi-parameter Design of Experiments generating test data at Cell level and also Pack level on a reduced basis. Based on experience, generating test data on a pack level is found to be very expensive, resource intensive and sometimes less reliable. The proposed collaborative project will focus on a methodology to estimate Battery life based on cell degradation data combined with pack thermal modeling. NREL has previously developed cell-level battery aging models and pack-level thermal/electrical network models, though these models are currently not integrated. When coupled together, the models are expected to describe pack-level thermal and aging response of individual cells. GM and NREL will use data collected for GM's Bas+ battery system for evaluation of the proposed methodology and assess to what degree these models can replace pack-level aging experiments in the future.

  2. On-line equalization for lithium-ion battery packs based on charging cell voltages: Part 1. Equalization based on remaining charging capacity estimation

    NASA Astrophysics Data System (ADS)

    Zheng, Yuejiu; Ouyang, Minggao; Lu, Languang; Li, Jianqiu; Han, Xuebing; Xu, Liangfei

    2014-02-01

    Because of the inevitable inconsistency during manufacture and use of battery cells, cell variations in battery packs have significant impacts on battery pack capacities, durability and safety for electric vehicles (EVs). To reduce cell variations and increase pack capacity, cell equalization is essentially required. In the series of two papers, we discover that dissipative cell equalization (DCE) using dissipative resistances is a feasible on-line equalization method for battery packs in EVs. We subsequently propose on-line equalization algorithms for lithium-ion battery packs based on charging cell voltage curves (CCVCs). The objective of these algorithms is to maximize pack capacities by conditioning CCVCs. As the first paper of the series, we first briefly review equalization topologies and algorithms. We discover cell remaining charging capacity (RCC) can be on-line estimated and further propose DCE algorithm based on remaining charging capacity estimation (RCCE). We establish a pack model with 8 cells in series and simulate 4 scenes with different cell variations. RCCE-DCE algorithm is proved to be effective by comparing pack capacities with/without RCCE-DCE algorithm. The equalization capability and over-equalization prevention are further examined, and the result shows that RCCE-DCE algorithm is suitable for on-line equalization in EVs.

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

    PubMed

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

    2015-01-07

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

  4. 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.

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

    PubMed

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

    2007-04-15

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

  6. Fermented red ginseng extract inhibits cancer cell proliferation and viability.

    PubMed

    Oh, Jisun; Jeon, Seong Bin; Lee, Yuri; Lee, Hyeji; Kim, Ju; Kwon, Bo Ra; Yu, Kang-Yeol; Cha, Jeong-Dan; Hwang, Seung-Mi; Choi, Kyung-Min; Jeong, Yong-Seob

    2015-04-01

    Red ginseng (Panax ginseng C.A. Meyer) is the most widely recognized medicinal herb due to its remedial effects in various disorders, such as cancers, diabetes, and heart problems. In this study, we investigated the anticancer effect of fermented red ginseng extract (f-RGE; provided by Jeonju Biomaterials Institute, Jeonju, South Korea) in a parallel comparison with the effect of nonfermented red ginseng extract (nf-RGE; control) on several cancer cell lines--MCF-7 breast cancer cells, HepG2 hepatocellular carcinoma cells, and reprogrammed MCF-7 cells (mimicking cancer stem cells). Cells were cultured at various concentrations of RGE (from 0.5 up to 5 mg/mL) and their viabilities and proliferative properties were examined. Our data demonstrate the following: (1) nf-RGE inhibited cell viability at ≥1 mg/mL for MCF-7 cells and ≥2 mg/mL for HepG2 cells, (2) in the presence of a carcinogenic agent, 12-O-tetradecanoylphorbol-13-acetate (TPA), nf-RGE treatment in combination with paclitaxel synergistically decreased MCF-7 as well as HepG2 cell viability, (3) f-RGE (which contained a greater level of Rg3 content) more effectively decreased the viability of MCF-7 and HepG2 cells compared to nf-RGE, and (4) f-RGE appeared more potent for inhibiting cancerous differentiation of reprogrammed MCF-7 cells in a synergistic fashion with paclitaxel, especially in the presence of TPA, compared to nf-RGE. These findings suggest that f-RGE treatment may be more effective for decreasing cancer cell survival by inducing apoptotic cell death and also presumably for preventing cancer stem cell differentiation compared to nf-RGE.

  7. Artificial Red Cells with Polyhemoglobin Membranes.

    DTIC Science & Technology

    1981-09-01

    preparing emulsions and ejecting cells from the oil phase. IX. REFERENCES 1. Wallace, H. W., Asher, W. J., and Li, N. N. Liquid - liquid oxygenation: a...1S. KEY WORDS (Continue, an reverse side if naceoay mnd identify by block number) Artificial Blood, Hemoglobin, Polyhemoglobin, Biotonometry Liquid ...cell-size microdroplets containing 30% of hemoglobin were held in liquid membrane capsules and treated with glutaralddhyde that cross linked the

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

    PubMed

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

    2005-06-01

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

  9. Role of red blood cell lysis and iron in hydrocephalus after intraventricular hemorrhage.

    PubMed

    Gao, Chao; Du, Hanjian; Hua, Ya; Keep, Richard F; Strahle, Jennifer; Xi, Guohua

    2014-06-01

    Thrombin and iron are two major players in intracerebral hemorrhage-induced brain injury and our recent study found that thrombin contributes to hydrocephalus development in a rat model of intraventricular hemorrhage (IVH). This study investigated the role of red blood cell (RBC) lysis and iron in hydrocephalus after IVH. There were three parts to this study. First, male Sprague-Dawley rats received an injection of saline, packed, or lysed RBCs into the right lateral ventricle. Second, rats had an intraventricular injection of iron or saline. Third, the rats received intraventricular injection of lysed RBCs mixed with deferoxamine (0.5 mg in 5 μL saline) or saline. All rats underwent magnetic resonance imaging at 24 hours and were then euthanized for brain edema measurement, western blot analysis, or brain histology. We found that intraventricular injection of lysed RBCs, but not packed RBCs, resulted in ventricular enlargement and marked increases in brain heme oxygenase-1 and ferritin at 24 hours. Intraventricular injection of iron also resulted in ventricular enlargement and ventricular wall damage 24 hours later. Coinjection of deferoxamine reduced lysed RBC-induced ventricular enlargement (P<0.01). These results suggest that iron, a degradation product of hemoglobin, has an important role in hydrocephalus development after IVH.

  10. Deoxygenation affects tyrosine phosphoproteome of red cell membrane from patients with sickle cell disease.

    PubMed

    Siciliano, Angela; Turrini, Franco; Bertoldi, Mariarita; Matte, Alessandro; Pantaleo, Antonella; Olivieri, Oliviero; De Franceschi, Lucia

    2010-04-15

    Sickle cell disease (SCD) is a worldwide distributed hereditary red cell disorder related to the production of a defective form of hemoglobin, hemoglobin S (HbS). One of the hallmarks of SCD is the presence of dense, dehydrate highly adhesive sickle red blood cells (RBCs) that result from persistent membrane damage associated with HbS polymerization, abnormal activation of membrane cation transports and generation of distorted and rigid red cells with membrane perturbation and cytoskeleton dysfunction. Although modulation of phosphorylation state of the proteins from membrane and cytoskeleton networks has been proposed to participate in red cell homeostasis, much still remains to be investigated in normal and diseased red cells. Here, we report that tyrosine (Tyr-) phosphoproteome of sickle red cells was different from normal controls and was affected by deoxygenation. We found proteins, p55 and band 4.1, from the junctional complex, differently Tyr-phosphorylated in SCD RBCs compared to normal RBCs under normoxia and modulated by deoxygenation, while band 4.2 was similarly Tyr-phosphorylated in both conditions. In SCD RBCs we identified the phosphopeptides for protein 4.1R located in the protein FERM domain (Tyr-13) and for alpha-spectrin located near or in a linker region (Tyr-422 and Tyr-1498) involving protein areas crucial for their functions in the context of red cell membrane properties, suggesting that Tyr-phosphorylation may be part of the events involved in maintaining membrane mechanical stability in SCD red cells.

  11. Adhesion of platelets to artificial surfaces: effect of red cells.

    PubMed

    Brash, J L; Brophy, J M; Feuerstein, I A

    1976-05-01

    Adhesion of platelets to several polymer- and protein-coated glass surfaces has been studied in vitro. The apparatus consists of a cylindrical probe rotating in a test tube containing the platelet medium and allows close control of fluid shear and mass transport. Suspensions of washed pig platelets constitute the basic platelet medium, and can be modified by adding back red cells and plasma proteins. Adhesion is measured via 51Cr-labeling of platelets. In the absence of red cells, identical low levels of adhesion were seen on all surfaces and saturation was reached within 2 min. In the presence of red cells, adhesion was greater. Saturation on all surfaces except fibrinogen and collagen again occurred within 2 min. The adhesion levels on polymer surfaces and glass were indistinguishable, while those on albumin were lower and those on fibrinogen were higher. Collagen was the most reactive surface. It did not equilibrate within 15 min., and kinetic data indicated a platelet diffusivity strongly dependent on hematocrit. These effects were attributed to rotational and translational motion of the red cells causing increased diffusion and surface-platelet collision energy.

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

    PubMed

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

    2017-03-01

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

  13. Quenching of red cell tryptophan fluorescence by mercurial compounds.

    PubMed

    Verkman, A S; Lukacovic, M F; Tinklepaugh, M S; Dix, J A

    1986-01-01

    Intrinsic tryptophan fluorescence in red cell ghost membranes labeled with N-ethylmaleimide (N-EM) is quenched in a dose-dependent manner by the organic mercurial p-chloromercuribenzene sulfonate (p-CMBS). Fluorescence lifetime analysis shows that quenching occurs by a static mechanism. Binding of p-CMBS occurs by a rapid (less than 5 s) biomolecular association (dissociation constant K1 = 1.8 mM) followed by a slower unimolecular transition with forward rate constant k2 = 0.015 s-1 and reverse rate constant k-2 = 0.0054 s-1. Analysis of the temperature dependence of k2 gives delta H = 6.5 kcal/mol and delta S = -21 eu. The mercurial compounds p-chloromercuribenzoic acid, p-aminophenylmercuric acetate, and mercuric chloride quench red cell tryptophan fluorescence by the same mechanism as p-CMBS does; the measured k2 value was the same for each compound, whereas K1 varied. p-CMBS also quenches the tryptophan fluorescence in vesicles reconstituted with purified band 3, the red cell anion exchange protein, in a manner similar to that in ghost membranes. These experiments define a mercurial binding site on band 3 in ghosts treated with N-EM and establish the binding mechanism to this site. The characteristics of this p-CMBS binding site on band 3 differ significantly from those of the p-CMBS binding site involved in red cell water and urea transport inhibition.

  14. Hereditary red cell membrane disorders and laboratory diagnostic testing.

    PubMed

    King, M-J; Zanella, A

    2013-06-01

    This overview describes two groups of nonimmune hereditary hemolytic anemias caused by defects in membrane proteins located in distinct layers of the red cell membrane. Hereditary spherocytosis (HS), hereditary elliptocytosis (HE), and hereditary pyropoikilocytosis (HPP) represent disorders of the red cell cytoskeleton. Hereditary stomatocytoses represents disorders of cation permeability in the red cell membrane. The current laboratory screening tests for HS are the osmotic fragility test, acid glycerol lysis time test (AGLT), cryohemolysis test, and eosin-5'-maleimide (EMA)-binding test. For atypical HS, SDS-polyacrylamide gel electrophoresis of erythrocyte membrane proteins is carried out to confirm the diagnosis. The diagnosis of HE/HPP is based on abnormal red cell morphology and the detection of protein 4.1R deficiency or spectrin variants using gel electrophoresis. None of screening tests can detect all HS cases. Some testing centers (a survey of 25 laboratories) use a combination of tests (e.g., AGLT and EMA). No specific screening test for hereditary stomatocytoses is available. The preliminary diagnosis is based on presenting a compensated hemolytic anemia, macrocytosis, and a temperature or time dependent pseudohyperkalemia in some patients. Both the EMA-binding test and the osmotic fragility test may help in differential diagnosis of HS and hereditary stomatocytosis.

  15. 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.

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

    NASA Astrophysics Data System (ADS)

    Wagner, Christian; Steffen, Patrick; Svetina, Saša

    2013-06-01

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

  17. 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

  18. 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.

  19. 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

  20. Biological Membrane-Packed Mesenchymal Stem Cells Treat Acute Kidney Disease by Ameliorating Mitochondrial-Related Apoptosis

    PubMed Central

    Geng, Xiaodong; Hong, Quan; Wang, Weiwei; Zheng, Wei; Li, Ou; Cai, Guangyan; Chen, Xiangmei; Wu, Di

    2017-01-01

    The mortality of rhabdomyolysis-induced AKI remains high because no effective therapy exists. We investigated a new therapeutic method using MSCs. The aim of this study was to investigate the therapeutic potential and anti-apoptotic mechanisms of action of MSCs in the treatment of AKI induced by glycerol in vivo and in vitro. We used Duragen as a biological membrane to pack MSCs on the glycerol-injured renal tissue in vivo. The anti-apoptotic mechanism was investigated. In vitro, HK-2 cells were incubated with ferrous myoglobin and MSCs-conditioned medium, followed by cell proliferation and apoptosis assays. We founded that packing MSCs on the injured renal tissue preserved renal function, ameliorated renal tubular lesions, and reduced apoptosis in the mice with glycerol-induced AKI. The MSC-conditioned medium improved HK-2 cell viability and inhibited apoptosis. These effects were reversed by the PI3K inhibitor LY294002. Biological membrane packing of MSCs on the renal tissue has a therapeutic rescue function by inhibiting cell apoptosis in vivo. MSCs protect renal cells from apoptosis induced by myoglobin in vitro. We have thus demonstrated MSCs reduced rhabdomyolysis-associated renal injury and cell apoptosis by activating the PI3K/Akt pathway and inhibiting apoptosis. PMID:28117405

  1. The red cell storage lesion(s): of dogs and men

    PubMed Central

    Klein, Harvey G.

    2017-01-01

    The advent of preservative solutions permitted refrigerated storage of red blood cells. However, the convenience of having red blood cell inventories was accompanied by a disadvantage. Red cells undergo numerous physical and metabolic changes during cold storage, the “storage lesion(s)”. Whereas controlled clinical trials have not confirmed the clinical importance of such changes, ethical and operational issues have prevented careful study of the oldest stored red blood cells. Suggestions of toxicity from meta-analyses motivated us to develop pre-clinical canine models to compare the freshest vs the oldest red blood cells. Our model of canine pneumonia with red blood cell transfusion indicated that the oldest red blood cells increased mortality, that the severity of pneumonia is important, but that the dose of transfused red blood cells is not. Washing the oldest red blood cells reduces mortality by removing senescent cells and remnants, whereas washing fresher cells increases mortality by damaging the red blood cell membrane. An opposite effect was found in a model of haemorrhagic shock with reperfusion injury. Physiological studies indicate that release of iron from old cells is a primary mechanism of toxicity during infection, whereas scavenging of cell-free haemoglobin may be beneficial during reperfusion injury. Intravenous iron appears to have toxicity equivalent to old red blood cells in the pneumonia model, suggesting that intravenous iron and old red blood cells should be administered with caution to infected patients. PMID:28263166

  2. The red cell storage lesion(s): of dogs and men.

    PubMed

    Klein, Harvey G

    2017-03-01

    The advent of preservative solutions permitted refrigerated storage of red blood cells. However, the convenience of having red blood cell inventories was accompanied by a disadvantage. Red cells undergo numerous physical and metabolic changes during cold storage, the "storage lesion(s)". Whereas controlled clinical trials have not confirmed the clinical importance of such changes, ethical and operational issues have prevented careful study of the oldest stored red blood cells. Suggestions of toxicity from meta-analyses motivated us to develop pre-clinical canine models to compare the freshest vs the oldest red blood cells. Our model of canine pneumonia with red blood cell transfusion indicated that the oldest red blood cells increased mortality, that the severity of pneumonia is important, but that the dose of transfused red blood cells is not. Washing the oldest red blood cells reduces mortality by removing senescent cells and remnants, whereas washing fresher cells increases mortality by damaging the red blood cell membrane. An opposite effect was found in a model of haemorrhagic shock with reperfusion injury. Physiological studies indicate that release of iron from old cells is a primary mechanism of toxicity during infection, whereas scavenging of cell-free haemoglobin may be beneficial during reperfusion injury. Intravenous iron appears to have toxicity equivalent to old red blood cells in the pneumonia model, suggesting that intravenous iron and old red blood cells should be administered with caution to infected patients.

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

    NASA Astrophysics Data System (ADS)

    Lee, Seungjun; Lu, Wei

    2011-08-01

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

  4. Assessing the Compatibility of Packed Red Blood Cells With Lactated Ringer’s Solution

    DTIC Science & Technology

    1998-10-01

    the use of human blood and blood components (AABB, 1995). The CRNA must be fully cognizant of the contents of this blood product circular of...approved for addition to blood components or for simultaneous administration via the same intravenous line include lactated...expanders, blood and blood components . Obviously, the potential exists for iatrogenic incompatibilities between the many different solutions that may

  5. Evaluation of Membrane Systems for Washing/Deglycerolizing Packed Red Blood Cells

    DTIC Science & Technology

    1987-03-20

    CLASSIFICATION Of THIS PAGE REPORT DOCUMENTATION PAGE Form Approved OM8 No 0704 0188 la REPORT SECURITY CLASSIFICATION Unclassified lb RESTRICTIVE...Bend Research, Inc. 6b OFFICE SYMBOL (if •pptktbh) 7a. NAME OF MONITORING ORGANIZATION •c AOOfttSS (City. State. end ZIP Code) 64550 Research Road...8b OFFICE SYMBOL (If ipplktble) 9 PROCUREMENT INSTRUMENT IDENTIFICATION NUMBER DAMD17-86-C-6142 8c AOORESSfOfy. Stttr ind ZIP Cod*) Fort

  6. Characterization of dsRed2-positive cells in the doublecortin-dsRed2 transgenic adult rat retina.

    PubMed

    Trost, A; Schroedl, F; Marschallinger, J; Rivera, F J; Bogner, B; Runge, C; Couillard-Despres, S; Aigner, L; Reitsamer, H A

    2014-12-01

    Doublecortin (DCX) is predominantly expressed in neuronal precursor cells and young immature neurons of the developing and adult brain, where it is involved in neuronal differentiation, migration and plasticity. Moreover, its expression pattern reflects neurogenesis, and transgenic DCX promoter-driven reporter models have been previously used to investigate adult neurogenesis. In this study, we characterize dsRed2 reporter protein-expressing cells in the adult retina of the transgenic DCX promoter-dsRed2 rat model, with the aim to identify cells with putative neurogenic activity. Additionally, we confirmed the expression of the dsRed2 protein in DCX-expressing cells in the adult hippocampal dentate gyrus. Adult DCX-dsRed2 rat retinas were analyzed by immunohistochemistry for expression of DCX, NF200, Brn3a, Sox2, NeuN, calbindin, calretinin, PKC-a, Otx2, ChAT, PSA-NCAM and the glial markers GFAP and CRALBP, followed by confocal laser-scanning microscopy. In addition, brain sections of transgenic rats were analyzed for dsRed2 expression and co-localization with DCX, NeuN, GFAP and Sox2 in the cortex and dentate gyrus. Endogenous DCX expression in the adult retina was confined to horizontal cells, and these cells co-expressed the DCX promoter-driven dsRed2 reporter protein. In addition, we encountered dsRed2 expression in various other cell types in the retina: retinal ganglion cells (RGCs), a subpopulation of amacrine cells, a minority of bipolar cells and in perivascular cells. Since also RGCs expressed dsRed2, the DCX-dsRed2 rat model might offer a useful tool to study RGCs in vivo under various conditions. Müller glial cells, which have previously been identified as cells with stem cell features and with neurogenic potential, did express neither endogenous DCX nor the dsRed2 reporter. However, and surprisingly, we identified a perivascular glial cell type expressing the dsRed2 reporter, enmeshed with the glia/stem cell marker GFAP and colocalizing with the

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

    PubMed

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

    2016-02-08

    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.

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

    NASA Astrophysics Data System (ADS)

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

    2017-03-01

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

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

    PubMed Central

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

    2017-01-01

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

  10. Alterations of Red Cell Membrane Properties in Nneuroacanthocytosis

    PubMed Central

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

    PubMed

    Bacus, J W

    1980-06-01

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

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

    PubMed

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

    1992-01-01

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

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

    NASA Astrophysics Data System (ADS)

    Peng, Zhangli; Lu, Huijie

    2016-11-01

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

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

    NASA Astrophysics Data System (ADS)

    Samant, Pratik; Chen, Jian; Xiang, Liangzhong

    2016-09-01

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

  16. Is pure red cell aplasia (PRCA) a clonal disorder?

    PubMed

    Sivakumaran, M; Bhavnani, M; Stewart, A; Roberts, B E; Geary, G C

    1993-01-01

    Pure red cell aplasia (PRCA) is an uncommon disorder, many cases lacking a well defined aetiology. This report describes three cases of PRCA (two idiopathic and one associated with B-CLL) who were investigated to assess the possibility of their PRCA being associated with a clonal proliferation of T-lymphocytes. The results show that one patient had evidence of T-cell receptor (TCR) gamma chain rearrangement, and the other had a TCR delta chain rearrangement. These two cases raise the possibility of PRCA being associated with a clonal proliferation of T-cells and further studies are warranted.

  17. 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.

  18. 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.

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

    PubMed

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

    1997-10-01

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

  20. 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.

  1. 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.

  2. 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.

  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. 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

  6. THE BIREFRINGENCE OF THE HUMAN RED CELL GHOSTS

    PubMed Central

    Ponder, Eric; Barreto, Delia

    1956-01-01

    The type of birefringence described by Mitchison, which extends some 0.5 µ in from the surface of the human red cell ghost in glycerol and which shows a maximum retardation of about 7 A, is only found in ghosts which are sufficiently well hemoglobinised to be seen with the ordinary microscope. Ghosts from which all hemoglobin has been lost are not visible with the ordinary microscope and are not birefringent, although they are clearly visible with phase contrast. About 90 per cent of the ghosts in glycerol preparations are of the latter type, the exact percentage being a function of time. Mitchison's measurements of birefringence, although reproducible, accordingly apply only to ghosts in which some hemoglobin still remains complexed with the lipoprotein layers of the red cell ultrastructure, and do not enable one to draw conclusions as to the thickness and orientation of the lipoprotein surface layers. PMID:13286451

  7. Patterns of Nonelectrolyte Permeability in Human Red Blood Cell Membrane

    PubMed Central

    Naccache, P.; Sha'afi, R. I.

    1973-01-01

    The permeability of human red cell membrane to 90 different molecules has been measured. These solutes cover a wide spectrum of nonelectrolytes with varying chemical structure, chain length, lipid solubility, chemical reactive group, ability to form hydrogen bonds, and other properties. In general, the present study suggests that the permeability of red cell membrane to a large solute is determined by lipid solubility, its molecular size, and its hydrogen-bonding ability. The permeability coefficient increases with increasing lipid solubility and decreasing ability to form hydrogen bonds, whereas it decreases with increasing molecular size. In the case of small solutes, the predominant diffusion factor is steric hindrance augmented by lipid solubility. It is also found that replacement of a hydroxyl group by a carbonyl group or an ether linkage tends to increase permeability. On the other hand, replacement of a hydroxyl group by an amide group tends to decrease the permeability coefficient. PMID:4804758

  8. 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.

  9. 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.

  10. 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.

  11. Pure Red Cell Aplasia Associated with Good Syndrome

    PubMed Central

    Okui, Masayuki; Yamamichi, Takashi; Asakawa, Ayaka; Harada, Masahiko; Horio, Hirotoshi

    2017-01-01

    Pure red cell aplasia (PRCA) and hypogammaglobulinemia are paraneoplastic syndromes that are rarer than myasthenia gravis in patients with thymoma. Good syndrome coexisting with PRCA is an extremely rare pathology. We report the case of a 50-year-old man with thymoma and PRCA associated with Good syndrome who achieved complete PRCA remission after thymectomy and postoperative immunosuppressive therapy, and provide a review of the pertinent literature. PMID:28382272

  12. 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.

  13. Role of Complement in Red Cell Dysfunction in Trauma

    DTIC Science & Technology

    2012-12-01

    3 Introduction Trauma-induced changes in the red blood cells ( RBC ) contribute to the reduction of blood flow to distant...The expression of C4d on the surface of RBCs was measured by flow cytometry and expressed as mean fluorescence intensity. (A) Representative data. (B...measured by flow cytometry. Fluorescence levels of RBCs were acquired for 30 seconds using FACScan flow cytometer to establish a baseline for intra- 8

  14. Research on red cell membrane permeability in arterial hypertension.

    PubMed

    Gatina, R; Balta, N; Moisin, C; Burtea, C; Botea, S; Ioan, M; Teleianu, C

    1998-01-01

    Arterial hypertension, including the elucidation of hypertension pathogenic mechanisms involving elements in the composition of the blood, continues to represent a topical research area. Recent work, such as nuclear magnetic resonance studies looking into red cell permeability, illustrates the presence of modifications of red cell permeability to water (RCPW) related to the stage of arterial hypertension. The identification of a significant increase of RCPW compared to that present in the population with normal arterial pressure values can be useful both in early diagnosis and in warning about a possible predisposition for this condition. At the same time, the dynamic investigation of protonic relaxation time of both intra- and extra-erythrocytic water, the assessment of proton exchange time across the red cell and the calculation of permeability to water enable one not only to diagnose arterial hypertension but also to ascertain the evolution of the disease, its complications and the effectiveness of anti-hypertensive medication. Our studies have also proven the existence of a correlation between the values of systolic arterial pressure and red cell permeability to water. The curve describing the interdependence of the two values has the shape of a bell, in the case of males. The peak of the curve is reached for a systolic pressure of 160 mmHg and gets below the values of the control group in the case of systolic pressures above 200 mmHg. The RCPW test can also be considered a valuable indicator in evaluating the risk of stroke in hypertensive patients. In the chronic therapy of arterial hypertension with various types of anti-hypertensive drugs, one can note differences in the RCPW values related to the effectiveness of the respective medication, to the clinical form and stage of the disease, the sex of the patient as well as to the existence of cerebro-vascular complications.

  15. Progress in improving the pathogen safety of red cell concentrates.

    PubMed

    Chapman, J

    2000-01-01

    Current methods of preparing red cell concentrates do not include a process step to decontaminate pathogens potentially present in the transfusion product. Although substantial progress has been made in the reduction of the frequency of transmission of HIV, HCV, HBV and HTLV-I as a result of the implementation of diagnostic screening processes, the need for further reduction in transmission rate of these viruses remains. In addition, there are viruses which are known to be be present in blood but for which no screening test has been implemented to remove contaminated units from the blood supply. These viruses include but are not limited to TTV, HGV and Parvo B19. Finally, the lack of a pathogen inactivation process for red cells maintains the blood supply in a state of vulnerability to new viruses or virus variants as they enter the donor population. Recently, substantial progress has been made in the research and development of a class of chemical compounds designated as INACTINE. These compounds are being investigated for their potential to inactivate viruses in red cells without adversely affecting their physiologic function. One of the INACTINE compounds, designated as PEN110, is now in the clinical trial phase of development.

  16. Thymoma associated with hypogammaglobulinaemia and pure red cell aplasia

    PubMed Central

    Briones, Juan; Iruretagoyena, Mirentxu; Galindo, Héctor; Ortega, Claudia; Zoroquiain, Pablo; Valbuena, José; Acevedo, Francisco; Ocqueteau, Mauricio; Sánchez, Cesar

    2013-01-01

    Thymomas are neoplasias that begin in the thymus and develop in the anterior mediastinum. They are commonly associated with a variety of systemic and autoimmune disorders, such as pure red cell aplasia, hypogammaglobulinaemia, pancytopaenia, collagen diseases, and, most commonly, myasthenia gravis. The presence of inter-current infections, especially diarrhoea and pneumonia, in the presence of lymphocyte B depletion and hypogammaglobulinaemia is known as Good’s syndrome and may affect up to 5% of patients with thymoma. While anaemia is present in 50%–86% of patients with Good’s syndrome, only 41.9% of cases present pure red cell aplasia. Concomitance of these two conditions has only been rarely studied. We report on the case of a 55-year-old man diagnosed with advanced thymoma, who, during the progression of his disease, developed signs and symptoms suggesting Good’s syndrome and pure red cell aplasia. We also performed a brief review of the literature concerning this association, its clinical characteristics, and treatment. PMID:24171048

  17. Study of Collagen Birefringence in Different Grades of Oral Squamous Cell Carcinoma Using Picrosirius Red and Polarized Light Microscopy

    PubMed Central

    Arun Gopinathan, Pillai; Kokila, Ganganna; Jyothi, Mahadesh; Ananjan, Chatterjee; Pradeep, Linganna; Humaira Nazir, Salroo

    2015-01-01

    Objectives. The present study was done to evaluate birefringence pattern of collagen fibres in different grades of oral squamous cell carcinoma using Picrosirius red stain and polarization microscopy and to determine if there is a change in collagen fibres between different grades of oral squamous cell carcinoma. Materials and Methods. Picrosirius red stained 5 μm thick sections of previously diagnosed different grades of squamous cell carcinoma and normal oral mucosa were studied under polarization microscopy for arrangement as well as birefringence of collagen fibres around tumour islands. Results. It was found that thin collagen fibres increased and thick collagen fibres decreased with dedifferentiation of OSCC (P < 0.0001). It was observed that there was change in polarization colours of thick fibres from yellowish orange to greenish yellow with dedifferentiation of OSCC indicating loosely packed fibres (P < 0.0001). Conclusion. There was a gradual change of birefringence of collagen from yellowish orange to greenish yellow from well to poorly differentiated squamous cell carcinoma, indicating that there is a change from mature form of collagen to immature form as tumour progresses. Studying collagen fibres with Picrosirius red for stromal changes around tumour islands along with routine staining may help in predicting the prognosis of tumour. PMID:26587310

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. 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.

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

    PubMed

    Foley, M; Tilley, L

    1995-11-01

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

  5. N-acetylcysteine improves the quality of red blood cells stored for transfusion.

    PubMed

    Amen, Florencia; Machin, Andrea; Touriño, Cristina; Rodríguez, Ismael; Denicola, Ana; Thomson, Leonor

    2017-04-06

    Storage inflicts a series of changes on red blood cells (RBC) that compromise the cell survival and functionality; largely these alterations (storage lesions) are due to oxidative modifications. The possibility of improving the quality of packed RBC stored for transfusion including N-acetylcysteine (NAC) in the preservation solution was explored. Relatively high concentrations of NAC (20-25 mM) were necessary to prevent the progressive leakage of hemoglobin, while lower concentrations (≥2.5 mM) were enough to prevent the loss of reduced glutathione during the first 21 days of storage. Peroxiredoxin-2 was also affected during storage, with a progressive accumulation of disulfide-linked dimers and hetero-protein complexes in the cytosol and also in the membrane of stored RBC. Although the presence of NAC in the storage solution was unable to avoid the formation of thiol-mediated protein complexes, it partially restored the capacity of the cell to metabolize H2O2, indicating the potential use of NAC as an additive in the preservation solution to improve RBC performance after transfusion.

  6. 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.

  7. 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

  8. 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.

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

    PubMed Central

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

    2016-01-01

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

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

    PubMed

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

    2016-05-01

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

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

    PubMed

    Barasa, Benjamin; Slijper, Monique

    2014-05-01

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

  12. Battery Pack Thermal Design

    SciTech Connect

    Pesaran, Ahmad

    2016-06-14

    This presentation describes the thermal design of battery packs at the National Renewable Energy Laboratory. A battery thermal management system essential for xEVs for both normal operation during daily driving (achieving life and performance) and off-normal operation during abuse conditions (achieving safety). The battery thermal management system needs to be optimized with the right tools for the lowest cost. Experimental tools such as NREL's isothermal battery calorimeter, thermal imaging, and heat transfer setups are needed. Thermal models and computer-aided engineering tools are useful for robust designs. During abuse conditions, designs should prevent cell-to-cell propagation in a module/pack (i.e., keep the fire small and manageable). NREL's battery ISC device can be used for evaluating the robustness of a module/pack to cell-to-cell propagation.

  13. 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.

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

    NASA Astrophysics Data System (ADS)

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

    2012-10-01

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

  15. Highly efficient polymer solar cells by step-by-step optimizing donor molecular packing and acceptor redistribution.

    PubMed

    Sun, Qianqian; Zhang, Fujun; An, Qiaoshi; Zhang, Miao; Wang, Jian; Zhang, Jian

    2016-12-21

    The dynamic drying process of the active layer should play a vitally important role in determining the performance of polymer solar cells (PSCs). Donor molecular packing and acceptor redistribution can be optimized by two successive post-treatments on the active layer. The blend films were freshly prepared by spin-coating method and then immediately transferred to a covered glass Petri dish to allow self-assembly of the donor molecules. The films were then treated with methanol or PFN-methanol solution to adjust the acceptor redistribution. In this study, power conversion efficiencies (PCEs) of PSCs with PffBT4T-2OD:PC71BM as the active layer were improved from 6.74% to 8.75% by employing 80 min for self-assembly and 20 s of methanol soaking. The PCE was improved even further to 9.72% by inserting a PFN interfacial layer. The performance improvement was mainly attributed to the optimized PffBT4T-2OD molecular packing during the self-assembly process, ideal vertical phase separation driven by methanol soaking and efficient charge collection by insertion of a PFN interfacial layer. The molecular packing and vertical phase separation were characterized by grazing incidence X-ray diffraction (GIXD), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS), respectively. The experimental results solidly supported the effectiveness of the step-by-step optimization strategy.

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

    PubMed

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

    2010-04-13

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

  17. Depletion induced clustering of red blood cells in microchannels

    NASA Astrophysics Data System (ADS)

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

    2012-11-01

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

  18. 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).

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

    PubMed

    Chesnutt, J K W; Marshall, J S

    2010-03-01

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

  20. 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).

  1. Red Fluorescent Carbon Nanoparticle-Based Cell Imaging Probe.

    PubMed

    Ali, Haydar; Bhunia, Susanta Kumar; Dalal, Chumki; Jana, Nikhil R

    2016-04-13

    Fluorescent carbon nanoparticle-based probes with tunable visible emission are biocompatible, environment friendly and most suitable for various biomedical applications. However, synthesis of red fluorescent carbon nanoparticles and their transformation into functional nanoparticles are very challenging. Here we report red fluorescent carbon nanoparticle-based nanobioconjugates of <25 nm hydrodynamic size and their application as fluorescent cell labels. Hydrophobic carbon nanoparticles are synthesized via high temperature colloid-chemical approach and transformed into water-soluble functional nanoparticles via coating with amphiphilic polymer followed by covalent linking with desired biomolecules. Following this approach, carbon nanoparticles are functionalized with polyethylene glycol, primary amine, glucose, arginine, histidine, biotin and folic acid. These functional nanoparticles can be excited with blue/green light (i.e., 400-550 nm) to capture their emission spanning from 550 to 750 nm. Arginine and folic acid functionalized nanoparticles have been demonstrated as fluorescent cell labels where blue and green excitation has been used for imaging of labeled cells. The presented method can be extended for the development of carbon nanoparticle-based other bioimaging probes.

  2. 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.

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

    PubMed Central

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

    1996-01-01

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

  4. Aplastic anemia and red cell aplasia due to pentachlorophenol

    SciTech Connect

    Roberts, H.J.

    1983-01-01

    Repeated exposure to commercial (technical grade) pentachlorophenol (PCP) preceded aplastic anemia in four patients and pure red cell aplasia in two. Two patients developed concomitant or subsequent Hodgkin's disease and acute leukemia. The hematologic, mutagenic, and carcinogenic effect of PCP and its chemical contaminants have been documented in other clinical and experimental reports. In view of the widespread contamination of our environment by PCP, clinicians and public health investigators must seek out such exposure in these and related disorders and initiate measures to reduce it.

  5. Pure red cell aplasia induced by epoetin zeta

    PubMed Central

    Panichi, Vincenzo; Ricchiuti, Guido; Scatena, Alessia; Del Vecchio, Lucia; Locatelli, Francesco

    2016-01-01

    Pure red cell aplasia (PRCA) may develop in patients with chronic kidney disease receiving erythropoiesis-stimulating agents (ESA). We report on a 72-year-old patient who developed hypo-proliferative anaemia unresponsive to ESA following the administration of epoetin zeta subcutaneously for 7 months. On the basis of severe isolated hypoplasia of the erythroid line in the bone marrow and high-titre neutralizing anti-erythropoietin antibodies (Ab), a diagnosis of Ab-mediated PRCA was made. Epoetin zeta was discontinued and the patient was given steroids. This was associated with anaemia recovery. To our knowledge this is the first PRCA case related to epoetin zeta. PMID:27478604

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

    PubMed

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

    2003-06-06

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

  7. Effect of asbestos on lipid peroxidation in the red cells.

    PubMed Central

    Gabor, S; Anca, Z

    1975-01-01

    In vitro exposure of red cells to vie International Union against Cancer (UICC) standard reference asbestos samples resulted in an increase of thiobarbituric acid substances. Chrysotiles developed the largest amounts of lipid peroxides, followed by anthophyllite, amosite, and crocidolite in decreasing order. Compared with the control samples erythrocytes free of dusts, all types of the asbestos examined disclosed significant differences. The results obtained provide support for the cytotoxic potential of amosite and crocidolite and, on the other hand, suggest that a lipid peroxidation of unsaturated fatty acids may be involved in the mechanisms(s) of membrane-damaging effects of asbestos dusts. PMID:1125126

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

    PubMed

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

    2015-10-01

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

  9. 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.

  10. 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

  11. Bio-inspired cryo-ink preserves red blood cell phenotype and function during nanoliter vitrification.

    PubMed

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

    2014-09-03

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

  12. 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

  13. The Ratio of Fibrinogen to Red Cells Transfused Affects Survival in Casualties Receiving Massive Transfusions at an Army Combat Support Hospital

    DTIC Science & Technology

    2007-10-01

    cell (RBC) units, fresh whole blood (FWB) units, fresh frozen plasma (FFP) units, cryoprecipitate (Cryo) 10-unit bags, and apheresis platelet (aPLT...cryoprecipitate; aPLT, apheresis platelets ; RBC, red blood cells. Table 1 Fibrinogen Content in Various Blood Products 1 unit of FFP 400 mg fibrinogen in 200...250 mL 1 six-pack of platelets 80 mg 6 units 480 mg in 300 mL 1 unit of apheresis platelets 300 mg in 200–250 mL 1 10-unit bag of cryoprecipitate

  14. Developments in red cell rheology at the Institut de Pathologie Cellulaire.

    PubMed

    Evans, E; Mohandas, N

    1986-01-01

    The present day rheological approximation, which has been used successfully to quantitate the deformability properties of red cells, is based on the view that the cell has a liquid interior encapsulated by a viscoelastic solid membrane shell. A review of historical developments in this field shows that determination of intrinsic red cell membrane properties has not come from simple mathematical analysis of experiments. On the contrary, considerable insight has been required to bring together physical and biological methods to rationalize the unique deformability characteristics of the red blood cell. Key developments at the Institut de Pathologie Cellulaire (IPC) in the early 1970s played a role in our improved understanding of red cell rheology. In this article, we describe the material concepts of the red cell membrane held before 1970, discuss the seminal developments at Bicetre, and, finally, outline the contemporary view of red cell deformability.

  15. Interaction of injectable neurotropic drugs with the red cell membrane.

    PubMed

    Reinhart, Walter H; Lubszky, Szabina; Thöny, Sandra; Schulzki, Thomas

    2014-10-01

    The normal red blood cell (RBC) shape is a biconcave discocyte. An intercalation of a drug in the outer half of the membrane lipid bilayer leads to echinocytosis, an intercalation in the inner half to stomatocytosis. We have used the shape transforming capacity of RBCs as a model to analyse the membrane interaction potential of various neurotropic drugs. Chlorpromazine, clomipramine, citalopram, clonazepam, and diazepam induced a reversible stomatocytosis, phenytoin induced echinocytosis, while the anticonvulsants levetiracetam, valproic acid and phenobarbital had no effect. This diversity of RBC shape transformations suggests that the pharmacological action is not linked to the membrane interaction. We conclude that this simple RBC shape transformation assay could be a useful tool to screen for potential drug interactions with cell membranes.

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

    PubMed

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

    2017-02-27

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

  17. A new material concept for the red cell membrane.

    PubMed

    Evans, E A

    1973-09-01

    The proposition is made that the red cell membrane is a two-dimensional, incompressible material and a general stress-strain law is developed for finite deformations. In the linear form, the character of such a material is analogous to a two-dimensional Mooney material (e.g., rubber), indicating that the molecular structure in the plane of the membrane would consist of long chains, randomly kinked and cross-linked in the natural state. The loose network could be provided by the protein component and the lipid phase could exist interstitially as a liquid bilayer, giving the membrane its two-dimensional incompressibility. The material provides the capability of large deformations exhibited by the discocyte and yet the rigidity associated with the osmotic spherocyte state. It is demonstrated that a membrane of this type can form a sphere at constant area. An illustrative example of the application to single cell discocyte-to-osmotic spherocyte transformations is presented.

  18. Geometric localization of thermal fluctuations in red blood cells

    PubMed Central

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

    2017-01-01

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

  19. 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.

  20. 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.

  1. An evidence-based approach to red blood cell transfusions in asymptomatically anaemic patients

    PubMed Central

    Chan, AW; de Gara, CJ

    2015-01-01

    Introduction Surgeons and physicians encounter blood transfusions on a daily basis but a robust evidence-based strategy on indications and timing of transfusion in asymptomatic anaemic patients is yet to be determined. For judicious use of blood products, the risks inherent to packed red blood cells, the patient’s co-morbidities and haemoglobin (Hb)/haematocrit levels should be considered. This review critiques and summarises the latest available evidence on the indications for transfusions in healthy and cardiac disease patients as well as the timing of transfusions relative to surgery. Methods An electronic literature search of the MEDLINE®, Google Scholar™ and Trip databases was conducted for articles published in English between January 2006 and January 2015. Studies discussing timing and indications of transfusion in medical and surgical patients were retrieved. Bibliographies of studies were checked for other pertinent articles that were missed by the initial search. Findings Six level 1 studies (randomised controlled trials or systematic reviews) and six professional society guidelines were included in this review. In healthy patients without cardiac disease, a restrictive transfusion trigger of Hb 70–80g/l is safe and appropriate whereas in cardiac patients, the trigger is Hb 80–100g/l. The literature on timing of transfusions relative to surgery is limited. For the studies available, preoperative transfusions were associated with a decreased incidence of subsequent transfusions and timing of transfusions did not affect the rates of colorectal cancer recurrence. PMID:26492900

  2. A system-based approach to modeling the ultrasound signal backscattered by red blood cells

    PubMed Central

    Fontaine, I; Bertrand, M; Cloutier, G

    1999-01-01

    A system-based model is proposed to describe and simulate the ultrasound signal backscattered by red blood cells (RBCs). The model is that of a space-invariant linear system that takes into consideration important biological tissue stochastic scattering properties as well as the characteristics of the ultrasound system. The formation of the ultrasound signal is described by a convolution integral involving a transducer transfer function, a scatterer prototype function, and a function representing the spatial arrangement of the scatterers. The RBCs are modeled as nonaggregating spherical scatterers, and the spatial distribution of the RBCs is determined using the Percus-Yevick packing factor. Computer simulations of the model are used to study the power backscattered by RBCs as a function of the hematocrit, the volume of the scatterers, and the frequency of the incident wave (2-500 MHz). Good agreement is obtained between the simulations and theoretical and experimental data for both Rayleigh and non-Rayleigh scattering conditions. In addition to these results, the renewal process theory is proposed to model the spatial arrangement of the scatterers. The study demonstrates that the system-based model is capable of accurately predicting important characteristics of the ultrasound signal backscattered by blood. The model is simple and flexible, and it appears to be superior to previous one- and two-dimensional simulation studies. PMID:10545342

  3. Experimental ultrasound characterization of red blood cell aggregation using the structure factor size estimator.

    PubMed

    Yu, François T H; Cloutier, Guy

    2007-07-01

    The frequency dependence of the ultrasonic backscattering coefficient (BSC) was studied to assess the level of red blood cell (RBC) aggregation. Three monoelement focused wideband transducers were used to insonify porcine blood sheared in a Couette flow from 9 to 30 MHz. A high shear rate was first applied to promote disaggregation. Different residual shear rates were then used to promote formation of RBC aggregates. The structure factor size estimator (SFSE), a second-order data reduction model based on the structure factor, was applied to the frequency-dependent BSC. Two parameters were extracted from the model to describe the level of aggregation at 6% and 40% hematocrits: W, the packing factor, and D the aggregate diameter, expressed in number of RBCs. Both parameters closely matched theoretical values for nonaggregated RBCs. W and D increased during aggregation with stabilized values modulated by the applied residual shear rate. Furthermore, parameter D during the kinetics of aggregation at 6% hematocrit under static conditions correlated with an optical RBC aggregate size estimation from microscopic images (r(2)=0.76). To conclude, the SFSE presents an interesting framework for tissue characterization of partially correlated dense tissues such as aggregated RBCs.

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

    PubMed

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

    2014-02-07

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

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

    PubMed

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

    2016-06-01

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

  6. 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.

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

    PubMed

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

    2008-01-01

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

  8. 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)

  9. 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.

  10. 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.

  11. New Developments in Red Blood Cell Preservation Using Liquid and Freezing Procedures.

    DTIC Science & Technology

    1982-04-02

    phosphate ion exchange resin.30 ൪ Solutions of bicarbonate, adenine, glucose and mannitol (BAGM), saline, adenine and RED BLOOD CELL PRESERVATION 10...glucose (SAO), and adenine, glucose, sodium chloride and mannitol (ADSOL), have been used to maintain or increase the red cell organic phosphate...compounds, ATP which influences posttransfusion survival, and 2,3 DPG which influences red cell oxygen transport function. Studies have shown that mannitol

  12. Rheology of red blood cell aggregation by computer simulation

    NASA Astrophysics Data System (ADS)

    Liu, Yaling; Liu, Wing Kam

    2006-12-01

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

  13. 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.

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

    PubMed

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

    2013-01-01

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

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

    PubMed

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

    2009-07-01

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

  16. The novel role of peroxiredoxin-2 in red cell membrane protein homeostasis and senescence.

    PubMed

    Matté, Alessandro; Pantaleo, Antonella; Ferru, Emanuela; Turrini, Franco; Bertoldi, Mariarita; Lupo, Francesca; Siciliano, Angela; Ho Zoon, Chae; De Franceschi, Lucia

    2014-11-01

    Peroxiredoxin-2 (Prx2), a typical two-cysteine peroxiredoxin, is the third most abundant protein in red cells. Although progress has been made in the functional characterization of Prx2, its role in red cell membrane protein homeostasis is still under investigation. Here, we studied Prx2(-/-) mouse red cells. The absence of Prx2 promotes (i) activation of the oxidative-induced Syk pathway; (ii) increased band 3 Tyr phosphorylation, with clustered band 3; and (iii) increased heat shock protein (HSP27 and HSP70) membrane translocation. This was associated with enhanced in vitro erythrophagocytosis of Prx2(-/-) red cells and reduced Prx2(-/-) red cell survival, indicating the possible role of Prx2 membrane recruitment in red cell aging and in the clearance of oxidized hemoglobin and damaged proteins through microparticles. Indeed, we observed an increased release of microparticles from Prx2(-/-) mouse red cells. The mass spectrometric analysis of erythroid microparticles found hemoglobin chains, membrane proteins, and HSPs. To test these findings, we treated Prx2(-/-) mice with antioxidants in vivo. We observed that N-acetylcysteine reduced (i) Syk activation, (ii) band 3 clusterization, (iii) HSP27 membrane association, and (iv) erythroid microparticle release, resulting in increased Prx2(-/-) mouse red cell survival. Thus, we propose that Prx2 may play a cytoprotective role in red cell membrane protein homeostasis and senescence.

  17. Red cell or serum folate: what to do in clinical practice?

    PubMed

    Farrell, Christopher-John L; Kirsch, Susanne H; Herrmann, Markus

    2013-03-01

    Folate deficiency has been linked to diverse clinical manifestations and despite the importance of accurate assessment of folate status, the best test for routine use is uncertain. Both serum and red cell folate assays are widely available in clinical laboratories; however, red cell folate is the more time-consuming and costly test. This review sought to evaluate whether the red cell assay demonstrated superior performance characteristics to justify these disadvantages. Red cell folate, but not serum folate, measurements demonstrated analytical variation due to sample pre-treatment parameters, oxygen saturation of haemoglobin and haematocrit. Neither marker was clearly superior in characterising deficiency but serum folate more frequently showed the higher correlation with homocysteine, a sensitive marker of deficiency. Similarly, both serum and red cell folate were shown to increase in response to folic acid supplementation. However, serum folate generally gave the greater response and was able to distinguish different supplementation doses. The C677T polymorphism of methylenetetrahydrofolate reductase alters the distribution of folate forms in red cells and may thereby cause further analytical variability in routine red cell folate assays. Overall, serum folate is cheaper and faster to perform than red cell folate, is influenced by fewer analytical variables and provides an assessment of folate status that may be superior to red cell folate.

  18. Dynamics of Red Cells in Spleen: How Does Vesiculation Happen?

    NASA Astrophysics Data System (ADS)

    Zhu, Qiang; Salehyar, Sara; Cabrales, Pedro; Asaro, Robert

    2016-11-01

    Vesiculation of red blood cells as a result of local separation between lipid bilayer and cytoskeleton is known to happen in vivo, most likely inside spleen where they sustain large mechanical loads during the passage through venus slits. There is, however, little knowledge about the detailed scenario and condition. We address this question via a fluid-cell interaction model by coupling a multiscale model of the cell membrane (including molecular details) with a fluid dynamics model based on boundary-integral equations. A numerical flow channel is created where the cell is driven through a narrow slit by pressure (imitating the transit through venus slits in spleen). The concentration is the occurrence of large dissociation (negative) pressure between the skeleton/membrane connection that promotes separation, a precursor of vesicle formation. Critical levels for the negative pressure are estimated using published data. By following the maximum range of pressure, we conclude that for vesiculation to happen there must be biochemical influences (e.g. binding of degraded haemoglobin) that significantly reduce effective attachment density. This is consistent with reported trends in vesiculation that are believed to occur in cases of various hereditary anemias and during blood storage. Our findings also suggest the criticality of understanding the biochemical phenomena involved with cytoskeleton/membrane attachment.

  19. Axial dispersion in flowing red blood cell suspensions

    NASA Astrophysics Data System (ADS)

    Podgorski, Thomas; Losserand, Sylvain; Coupier, Gwennou

    2016-11-01

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

  20. 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.

  1. 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.

  2. Minimal RED cell pairs markedly improve electrode kinetics and power production in microbial reverse electrodialysis cells.

    PubMed

    Cusick, Roland D; Hatzell, Marta; Zhang, Fang; Logan, Bruce E

    2013-12-17

    Power production from microbial reverse electrodialysis cell (MRC) electrodes is substantially improved compared to microbial fuel cells (MFCs) by using ammonium bicarbonate (AmB) solutions in multiple RED cell pair stacks and the cathode chamber. Reducing the number of RED membranes pairs while maintaining enhanced electrode performance could help to reduce capital costs. We show here that using only a single RED cell pair (CP), created by operating the cathode in concentrated AmB, dramatically increased power production normalized to cathode area from both acetate (Acetate: from 0.9 to 3.1 W/m(2)-cat) and wastewater (WW: 0.3 to 1.7 W/m(2)), by reducing solution and charge transfer resistances at the cathode. A second RED cell pair increased RED stack potential and reduced anode charge transfer resistance, further increasing power production (Acetate: 4.2 W/m(2); WW: 1.9 W/m(2)). By maintaining near optimal electrode power production with fewer membranes, power densities normalized to total membrane area for the 1-CP (Acetate: 3.1 W/m(2)-mem; WW: 1.7 W/m(2)) and 2-CP (Acetate: 1.3 W/m(2)-mem; WW: 0.6 W/m(2)) reactors were much higher than previous MRCs (0.3-0.5 W/m(2)-mem with acetate). While operating at peak power, the rate of wastewater COD removal, normalized to reactor volume, was 30-50 times higher in 1-CP and 2-CP MRCs than that in a single chamber MFC. These findings show that even a single cell pair AmB RED stack can significantly enhance electrical power production and wastewater treatment.

  3. A red/far-red light-responsive bi-stable toggle switch to control gene expression in mammalian cells

    PubMed Central

    Müller, Konrad; Engesser, Raphael; Metzger, Stéphanie; Schulz, Simon; Kämpf, Michael M.; Busacker, Moritz; Steinberg, Thorsten; Tomakidi, Pascal; Ehrbar, Martin; Nagy, Ferenc; Timmer, Jens; Zubriggen, Matias D.; Weber, Wilfried

    2013-01-01

    Growth and differentiation of multicellular systems is orchestrated by spatially restricted gene expression programs in specialized subpopulations. The targeted manipulation of such processes by synthetic tools with high-spatiotemporal resolution could, therefore, enable a deepened understanding of developmental processes and open new opportunities in tissue engineering. Here, we describe the first red/far-red light-triggered gene switch for mammalian cells for achieving gene expression control in time and space. We show that the system can reversibly be toggled between stable on- and off-states using short light pulses at 660 or 740 nm. Red light-induced gene expression was shown to correlate with the applied photon number and was compatible with different mammalian cell lines, including human primary cells. The light-induced expression kinetics were quantitatively analyzed by a mathematical model. We apply the system for the spatially controlled engineering of angiogenesis in chicken embryos. The system’s performance combined with cell- and tissue-compatible regulating red light will enable unprecedented spatiotemporally controlled molecular interventions in mammalian cells, tissues and organisms. PMID:23355611

  4. Vesicles, capsules and red blood cells under flow

    NASA Astrophysics Data System (ADS)

    Misbah, Chaouqi

    2012-12-01

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

  5. 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.

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

    NASA Astrophysics Data System (ADS)

    Mancuso, Jordan; Ristenpart, William

    2016-11-01

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

  7. 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.

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

    PubMed

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

    1997-01-01

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

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

    PubMed Central

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

    2017-01-01

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

  10. Pressure and temperature effects on human red cell cation transport.

    PubMed

    Hall, A C; Ellory, J C; Klein, R A

    1982-01-01

    The effects of hydrostatic pressure and temperature on the three components of K+ uptake in human red cells have been investigated, using ouabain and bumetanide to distinguish between the pump, passive diffusion and cotransport. The pressure sensitivity for passive diffusion has been shown to depend on the counter-ion present. The order of this effect, Cl- greater than Br- greater than NO3- greater than I-, is the same as for the ionic partial molal volumes and the Hofmeister series. We have analyzed our experimental results thermodynamically, and propose a model for the activated transition-state complex of the potassium ion which involves the loss of water molecules from the secondary hydration shell, cosphere II.

  11. 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.

  12. 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.

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

    PubMed

    Sluyter, Ronald

    2015-01-01

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

  14. Importance of Mean Red Cell Distribution Width in Hypertensive Patients

    PubMed Central

    Bilal, Ahmed; Farooq, Junaid H; Assad, Salman; Ghazanfar, Haider; Ahmed, Imran

    2016-01-01

    Purpose Red cell distribution width (RDW), expressed in femtoliters (fl), is a measure of the variation in the size of circulating erythrocytes and is often expressed as a direct measurement of the width of the distribution. We aim to observe the mean value of red cell distribution width (RDW) in hypertensive patients. Increased RDW can be used as a tool for early diagnosis, as an inflammatory marker, and a mortality indicator in hypertensive patients due to its close relation to inflammation. Materials and methodology Hypertensive patients who had the condition for more than one year duration, diagnosed according to the Joint National Committee (JNC 7) criteria were subjected to complete blood count and RDW measurement. One hundred patients, aged between 12 years and 65 years were enrolled from the outpatient department of medicine at the Military Hospital Rawalpindi. Results The mean age (± SD) of the patients was 51.48 ± 10.08 years. Out of 100 patients 69% were males whereas 31% were females. The overall frequency of hypertension more than five years was 55% subjects whereas 45% individuals had duration of hypertension less than five years. Mean RDW in females was found to be 49.35±8.42 fl while mean RDW in males was 44.78±7.11 fl. An independent sample t-test was applied to assess if there was any significant difference between age and gender. No significant difference between age and gender was found (p<0.05). The Mann-Whitney test was used to assess any association of RDW with gender. RDW values in females was found to be statistically significantly higher than in males (U=603, p=0.01). Linear regression showed that mean RDW value increased with increasing age (P <0.001). Conclusions A significant number of patients with hypertension have increased levels of RDW. Therefore, it is recommended that serum RDW should be checked regularly in patients with hypertension. PMID:28070471

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

    PubMed

    Naina, Harris V K; Harris, Samar

    2010-01-01

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

  16. Clinical utility of flow cytometry in the study of erythropoiesis and nonclonal red cell disorders.

    PubMed

    Chesney, Alden; Good, David; Reis, Marciano

    2011-01-01

    Erythropoiesis involves proliferation and differentiation of small population of hematopoietic stem cells resident in the bone marrow into mature red blood cells. The determination of the cellular composition of the blood is a valuable tool in the diagnosis of diseases and monitoring of therapy. Flow cytometric analysis is increasingly being used to characterize the heterogeneous cell populations present in the blood and the hematopoietic cell differentiation and maturation pathways of the bone marrow. Here we discuss the role of flow cytometry in the study of erythropoiesis and nonclonal red blood cell disorders. First, we discuss flow cytometric analysis of reticulocytes. Next, we review salient quantitative methods that can be used for detection of fetal-maternal hemorrhage (FMH). We also discuss flow cytometric analysis of high hemoglobin F (HbF) in Sickle Cell Disease (SCD), hereditary spherocytosis (HS), red cell survival and red cell volume. We conclude by discussing cell cycle of erythroid cells.

  17. Red blood cell as an adaptive optofluidic microlens

    NASA Astrophysics Data System (ADS)

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

    2015-03-01

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

  18. 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.

  19. Red blood cell as an adaptive optofluidic microlens.

    PubMed

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

    2015-03-11

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

  20. Fibrinogen and red blood cells in venous thrombosis.

    PubMed

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

    2014-05-01

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

  1. Pure red cell aplasia and lymphoproliferative disorders: an infrequent association.

    PubMed

    Vlachaki, Efthymia; Diamantidis, Michael D; Klonizakis, Philippos; Haralambidou-Vranitsa, Styliani; Ioannidou-Papagiannaki, Elizabeth; Klonizakis, Ioannis

    2012-01-01

    Pure red cell aplasia (PRCA) is a rare bone marrow failure syndrome defined by a progressive normocytic anaemia and reticulocytopenia without leukocytopenia and thrombocytopenia. Secondary PRCA can be associated with various haematological disorders, such as chronic lymphocytic leukaemia (CLL) or non-Hodgkin lymphoma (NHL). The aim of the present review is to investigate the infrequent association between PRCA and lymphoproliferative disorders. PRCA might precede the appearance of lymphoma, may present simultaneously with the lymphoid neoplastic disease, or might appear following the lymphomatic disorder. Possible pathophysiological molecular mechanisms to explain the rare association between PRCA and lymphoproliferative disorders are reported. Most cases of PRCA are presumed to be autoimmune mediated by antibodies against either erythroblasts or erythropoietin, by T-cells secreting factors selectively inhibiting erythroid colonies in the bone marrow or by NK cells directly lysing erythroblasts. Finally, focus is given to the therapeutical approach, as several treatment regimens have failed for PRCA. Immunosuppressive therapy and/or chemotherapy are effective for improving anaemia in the majority of patients with lymphoma-associated PRCA. Further investigation is required to define the pathophysiology of PRCA at a molecular level and to provide convincing evidence why it might appear as a rare complication of lymphoproliferative disorders.

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

    PubMed

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

    2014-01-01

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

  3. AUR memorial award--1988. MRI enhancement of perfused tissues using chromium labeled red blood cells as an intravascular contrast agent

    SciTech Connect

    Eisenberg, A.D.; Conturo, T.E.; Price, R.R.; Holburn, G.E.; Partain, C.L.; James, A.E. Jr. )

    1989-10-01

    It has been demonstrated that chromium (Cr) labeling significantly decreases the relaxation times of packed red blood cells (RBCs). In this study, the spin-lattice relaxation time (T1) of human red cells was shortened from 836 ms to 29 ms and the spin-spin relaxation time (T2) shortened from 134 ms to 18 ms, when the cells were labeled at a Cr incubation concentration of 50 mM. Labeling of canine cells at 50 mM resulted in a T1 of 36 ms and a T2 of 26 ms. A labeling concentration of 10 mM produced similar relaxation enhancement, with uptake of 47% of the available Cr, and was determined to be optimal. The enhancement of longitudinal and transverse relaxation rates (1/T1,-1/T2) per amount of hemoglobin-bound Cr are 6.9 s-1 mM-1 and 9.8 s-1 mM-1 respectively, different from those of a pure Cr+3 solution. Labeling cells at 10 mM decreased the survival half-time in vivo from 16.6 days to 4.7 days in dogs. No difference in red cell survival was found with the use of hetero-transfusion versus auto-transfusion of labeled RBCs. Significant shortening of the T1 (912 ms to 266 ms, P = .03) and T2 (90 ms to 70 ms, P = .006) of spleen and the T1 (764 ms to 282 ms, P = .005) and the T2 (128 ms to 86 ms, P = .005) of liver occurred when 10% of the RBC mass of dogs was exchanged with Cr labeled cells. Liver and spleen spin density changes (P greater than 0.23) and muscle spin density and relaxation changes (P greater than 0.4) were insignificant. The in vivo T1 of a canine spleen which had been infarcted did not change following transfusion with labeled cells, where the T1 of liver did shorten. We believe this preliminary study suggests that Cr labeled red cells may have the potential to become an intravascular magnetic resonance imaging contrast agent.

  4. 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.

  5. 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.

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

    PubMed

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

    2016-05-06

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

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

    PubMed

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

    2014-05-01

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

  8. Ambient temperature and relative humidity influenced packed cell volume, total plasma protein and other variables in horses during an incremental submaximal field exercise test.

    PubMed

    Hargreaves, B J; Kronfeld, D S; Naylor, J R

    1999-07-01

    Thermoregulation may limit exercise performance under hot and humid conditions. This study compared heart rate (HR), respiratory rate (RR), rectal temperature (Tr), packed cell volume (PCV) and total plasma protein concentration (TPP) during a submaximal incremental field exercise test under high vs. low ambient temperature and relative humidity. Ten horses were tested 3 times in summer (July) and 3 times in autumn (September). Heart rate was measured continuously, the other variables at rest and immediately after 4 min at 3.5, 4.5 and 7.0 m/s, separated by 3 min rest intervals, and after 5 and 10 min recovery. Data for all variables were significantly greater during exercise and recovery in the hot vs. cool conditions, respectively: after 4 min at 7.0 m/s, HR was 135+/-1 and 123+/-1/min (P<0.0001), Tr was 39.0+/-0.06 and 38.0+/-0.05 degrees C (P<0.0001), RR was 99+/-3 and 50+/-3/min (P<0.0001), PCV was 48.8+/-0.06 and 42.1+/-0.3% (P<0.0001) and TPP was 7.7+/-0.14 and 7.6+/-0.12 g/l (P = 0.026). These data reflect the thermal burden during submaximal exercise under hot conditions in the field. The greater relative PCV increase in the heat probably conferred a thermoregulatory advantage and reflected a greater circulating red cell volume increase rather than a decrease of plasma volume. This study illustrates how differences in environmental conditions can affect assessment of exercise responses and how these factors must be considered in monitoring progress during fitness and acclimatisation regimes in the field.

  9. Valve Packing

    NASA Technical Reports Server (NTRS)

    1992-01-01

    "S Glass" yarn was originally developed by NASA for high temperature space and aeronautical applications. When John Crane, Inc. required material that would withstand temperatures higher than 1,200 degrees Fahrenheit, they contacted Owens-Corning, which had developed a number of applications for the material. John Crane combines the yarn with other components to make Style 287-I packing. The product can be used in chemical processing operations, nuclear power stations, petroleum products, etc. Advantages include increased service life and reduced maintenance costs.

  10. 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.

  11. Modulation of ligand-mediated human red cell agglutinability by prostaglandins

    SciTech Connect

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

    1986-03-01

    Ethanol induces the transformation of human red cells from bioconcave discs to echinocytes in vitro. In addition, they have observed that ethanol can enhance the agglutination of red cells by the plant lectin wheat germ agglutinin or poly-L-lysine. Incubation of washed human red cells with 5 and 10% ethanol (v/v) in phosphate buffered saline, pH 7.3 at 25/sup 0/C produced a 30% increase in ligand-mediated agglutinability within 12 min. Simultaneous addition of ethanol and one of the following prostaglandin derivatives, PGE/sub 1/, pge/sub 2/, pgf/sub 2/-alpha, or PGl/sub 2/ (10/sup -9/ to 5 x 10/sup -7/ M) prevented the shape-associated increases in red cell agglutinability. Thromboxane-B/sub 2/ had no effect on agglutinability. Prostaglandins did not prevent ethanol-induced red cell shape transformations per se under identical experimental conditions. As intragastric administration of 100% ethanol results in the formation of spiculated red cell thrombi in postcapillary venules of rat gastric mucosa, they postulate that the cytoprotective role of prostanoids in preventing mucosal ulceration may be due in part to their capacity to inhibit intravascular ligand mediated red cell agglutination, hemostasis, and their sequelae, epithelial necrosis. Moreover, the data suggest that ethanol-induced red cell shape transformations and ligand-mediated agglutination represent two distinct and independent biological phenomena.

  12. 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

  13. A Teenage Girl with Acute Dyspnea and Hypoxemia during Red Blood Cell Transfusion

    PubMed Central

    Tanpowpong, P.; Thongpo, P.

    2016-01-01

    Transfusion-related acute lung injury (TRALI) can cause morbidity and mortality. We present the case of teenager who developed dyspnea and hypoxemia few hours after red cell transfusion. After being admitted for close monitoring and oxygen therapy, her symptoms spontaneously resolved. Message: dyspnea during red cell transfusion should raise the suspicion of TRALI. PMID:27891282

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

    PubMed

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

    2005-03-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2005-08-01

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

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

    PubMed Central

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

    2016-01-01

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

  17. Dynamics of Red Blood Cells through submicronic splenic slits

    NASA Astrophysics Data System (ADS)

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

    2016-11-01

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

  18. 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.

  19. Measurement of posttransfusion red cell survival with the biotin label.

    PubMed

    Mock, Donald M; Widness, John A; Veng-Pedersen, Peter; Strauss, Ronald G; Cancelas, Jose A; Cohen, Robert M; Lindsell, Christopher J; Franco, Robert S

    2014-07-01

    The goal of this review is to summarize and critically assess information concerning the biotin method to label red blood cells (RBC) for use in studies of RBC and transfusion biology-information that will prove useful to a broad audience of clinicians and scientists. A review of RBC biology, with emphasis on RBC senescence and in vivo survival, is included, followed by an analysis of the advantages and disadvantages of biotin-labeled RBC (BioRBC) for measuring circulating RBC volume, posttransfusion RBC recovery, RBC life span, and RBC age-dependent properties. The advantages of BioRBC over (51)Cr RBC labeling, the current reference method, are discussed. Because the biotin method is straightforward and robust, including the ability to follow the entire life spans of multiple RBC populations concurrently in the same subject, BioRBC offers distinct advantages for studying RBC biology and physiology, particularly RBC survival. The method for biotin labeling, validation of the method, and application of BioRBCs to studies of sickle cell disease, diabetes, and anemia of prematurity are reviewed. Studies documenting the safe use of BioRBC are reviewed; unanswered questions requiring future studies, remaining concerns, and regulatory barriers to broader application of BioRBC including adoption as a new reference method are also presented.

  20. Kinematics of red cell aspiration by fluorescence-imaged microdeformation.

    PubMed Central

    Discher, D E; Mohandas, N

    1996-01-01

    Maps of fluorescing red cell membrane components on a pipette-aspirated projection are quantitated in an effort to elucidate and unify the heterogeneous kinematics of deformation. Transient gradients of diffusing fluorescent lipid first demonstrate the fluidity of an otherwise uniform-density bilayer and corroborate a "universal" calibration scale for relative surface density. A steep but smooth and stable gradient in the densities of the skeleton components spectrin, actin, and protein 4.1 is used to estimate large elastic strains along the aspirated skeleton. The deformation fields are argued to be an unhindered response to loading in the surface normal direction. Density maps intermediate to those of the compressible skeleton and fluid bilayer are exhibited by particular transmembrane proteins (e.g., Band 3) and yield estimates for the skeleton-connected fractions. Such connected proteins appear to occupy a significant proportion of the undeformed membrane surface and can lead to steric exclusion of unconnected integral membrane proteins from regions of network condensation. Consistent with membrane repatterning kinematics in reversible deformation, final vesiculation of the projection tip produces a cell fragment concentrated in freely diffusing proteins but depleted of skeleton. Images FIGURE 1 FIGURE 2 FIGURE 4 FIGURE 5 FIGURE 7 FIGURE 8 FIGURE 9 FIGURE 10 FIGURE 11 PMID:8889146

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

    PubMed

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

    2008-06-01

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

  2. Invasive Thymoma with Pure Red Cell Aplasia and Amegakaryocytic Thrombocytopenia

    PubMed Central

    Kiyoki, Yusuke; Ueda, Sho; Yamaoka, Masatoshi; Shimizu, Seiich; Inagaki, Masaharu

    2016-01-01

    We here describe a case involving a 67-yearold female patient who was referred to our hospital due to severe anemia (hemoglobin, 5.0 g/dL), thrombocytopenia (platelet count, 0.6 × 104/μL), and a mediastinal shadow with calcification noted on X-ray. On admission, an anterior mediastinal tumor was detected, and bone marrow biopsy revealed few megakaryocytes and severely reduced numbers of erythroid cells. The diagnosis was thymoma with pure red cell aplasia (PRCA) and acquired amegakaryocytic thrombocytopenia (AAMT). On Day 8 of admission, the patient received immunosuppressive therapy together with cyclosporine for the 2 severe hematologic diseases, which were stabilized within 2 months. Subsequently, total thymectomy was performed. The diagnosis of the tumor invading the left lung was invasive thymoma, Masaokakoga stage III. The histological diagnosis was World Health Organization type AB. Thymoma accompanied with PRCA and AAMT is very rare, and, based on our case, immunotherapeutic therapy for the hematologic disorders should precede surgical intervention. PMID:28053696

  3. A thermal packed-bed reactor and a silent discharge plasma cell for a two-stage treatment system

    NASA Astrophysics Data System (ADS)

    Godoy-Cabrera, O. G.; López-Callejas, R.; Mercado-Cabrera, A.; Barocio, S. R.; Valencia, R.; Muñoz-Castro, A.; Peña Eguiluz, R.; de la Piedad-Beneitez, A.

    2006-08-01

    Dielectric barrier discharge cells (DBDCs) have proved their efficiency in the generation of cold plasmas for hazardous organic compound degradation. Here, we describe the design and construction of a dual thermal packed-bed reactor and DBDC-based system to carry out the degradation of hazardous organic compounds in both liquid and gas phases. The main components of this system are: (i) the thermal treatment system, (ii) DBDC and (iii) resonant inverters of low (3.3 kHz) and high (100 kHz) calculated frequencies. The definition of the cell physical parameters considers: (a) a first-order degradation ratio of the compound and (b) the air breakdown at atmospheric pressure as a function of the transport carrier gas. The power consumed by the cells during the discharges was computed theoretically and experimentally. Using the dual system along with a gas chromatography diagnostic system, highly efficient degradations of a test compound (benzene) have been obtained, reaching 99.950% in the case of a cell experimentally operated at 3.3 kHz and up to 99.996% in another one at 94.3 kHz. An additional 3.7 times reduction in the latter case residence time with respect to the low frequency cell has been found.

  4. 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

  5. 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.

  6. [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.

  7. 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

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

    PubMed

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

    2013-02-01

    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.

  9. An enzyme-linked immunoabsorbent assay for estimating red cell survival of transfused red cells-validation using CR-51 labeling

    SciTech Connect

    Drew, H.; Kickler, T.; Smith, B.; LaFrance, N.

    1984-01-01

    The survival time of transfused red cells antigenically distinct from the recipient's red cells was determined using an indirect enzyme linked antiglobulin test. These results were then compared to those determined by Cr-51 labeling. Three patients with hypoproliferative anemias and one patient (2 studies) with traumatic hemolytic anemia caused by a prosthetic heart valve were studied. Survival times were performed by transfusing a 5cc aliquot of Cr-51 labeled cells along with the remaining unit. One hour post transfusion, a blood sample was drawn and used as the 100% value. Subsequent samples drawn over a 2-3 week period were then compared to the initial sample to determine percent survival for both methods. The ELISA method for measuring red cell survival in antigenically distinct cells is in close agreement with the Cr-51 method. Although CR-51 labeling is the accepted method for red cell survival determination the ELISA method can be used when radioisotopes are unavailable or contraindicated or when the decision to estimate red cell survival is made after transfusion.

  10. 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

    2015-10-08

    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.

  11. Elastic thickness compressibilty of the red cell membrane.

    PubMed

    Heinrich, V; Ritchie, K; Mohandas, N; Evans, E

    2001-09-01

    We have used an ultrasensitive force probe and optical interferometry to examine the thickness compressibility of the red cell membrane in situ. Pushed into the centers of washed-white red cell ghosts lying on a coverglass, the height of the microsphere-probe tip relative to its closest approach on the adjacent glass surface revealed the apparent material thickness, which began at approximately 90 nm per membrane upon detection of contact (force approximately 1-2 pN). With further impingement, the apparent thickness per membrane diminished over a soft compliant regime that spanned approximately 40 nm and stiffened on approach to approximately 50 nm under forces of approximately 100 pN. The same force-thickness response was obtained on recompression after retraction of the probe, which demonstrated elastic recoverability. Scaled by circumferences of the microspheres, the forces yielded energies of compression per area which exhibited an inverse distance dependence resembling that expected for flexible polymers. Attributed to the spectrin component of the membrane cytoskeleton, the energy density only reached one thermal energy unit (k(B)T) per spectrin tetramer near maximum compression. Hence, we hypothesized that the soft compliant regime probed in the experiments represented the compressibility of the outer region of spectrin loops and that the stiff regime < 50 nm was the response of a compact mesh of spectrin backed by a hardcore structure. To evaluate this hypothesis, we used a random flight theory for the entropic elasticity of polymer loops to model the spectrin network. We also examined the possibility that additional steric repulsion and apparent thickening could arise from membrane thermal-bending excitations. Fixing the energy scale to k(B)T/spectrin tetramer, the combined elastic response of a network of ideal polymer loops plus the membrane steric interaction correlated well with the measured dependence of energy density on distance for a statistical

  12. 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.

  13. 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

  14. [Role of protein kinases of human red cell membrane in deformability and aggregation changes].

    PubMed

    Murav'ev, A V; Maĭmistova, A A; Tikhomirova, I A; Bulaeva, S V; Mikhaĭlov, P V; Murav'ev, A A

    2012-01-01

    The proteomic analysis has showed that red cell membrane contains several kinases and phosphatases. Therefore the aim of this study was to investigate the role of protein kinases of human red cell membrane in deformability and aggregation changes. Exposure of red blood cells (RBCs) to some chemical compounds led to change in the RBC microrheological properties. When forskolin (10 microM), an adenylyl cyclase (AC) and a protein kinase A (PKA) stimulator was added to RBC suspension, the RBC deformability (RBCD) was increased by 20% (p < 0.05). Somewhat more significant deformability rise appeared after RBC incubation with dB-AMP (by 26%; p < 0.01). Red cell aggregation (RBCA) was significantly decreased under these conditions (p < 0.01). Markedly less changes of deformability was found after RBC incubation with protein kinase stimulator C (PKC)--phorbol 12-myristate 13-acetate (PMA). This drug reduced red cell aggregation only slightly. It was inhibited red cell tyrosine phosphotase activity by N-vanadat and was obtained a significant RBCD rise and RBCA lowering. The similar effect was found when cells were incubated with cisplatin as a tyrosine protein kinase (TPK) activator. It is important to note that a selective TPK inhibitor--lavendustin eliminated the above mention effects. On the whole the total data clearly show that the red cell aggregation and deformation changes were connected with an activation of the different intracellular signaling pathways.

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

    PubMed Central

    Lei, Chong; Xiong, Li-Ze

    2015-01-01

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

  16. 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.

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

    PubMed

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

    2008-01-01

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

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

    PubMed

    Yoon, Daegeun; You, Donghyun

    2016-07-26

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

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

    NASA Astrophysics Data System (ADS)

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

    1995-01-01

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

  20. Probing red cell membrane cholesterol movement with cyclodextrin.

    PubMed

    Steck, Theodore L; Ye, Jin; Lange, Yvonne

    2002-10-01

    We probed the kinetics with which cholesterol moves across the human red cell bilayer and exits the membrane using methyl-beta-cyclodextrin as an acceptor. The fractional rate of cholesterol transfer (% s(-1)) was unprecedented, the half-time at 37 degrees C being ~1 s. The kinetics observed under typical conditions were independent of donor concentration and directly proportional to acceptor concentration. The rate of exit of membrane cholesterol fell hyperbolically to zero with increasing dilution. The energy of activation for cholesterol transfer was the same at high and low dilution; namely, 27-28 Kcal/mol. This behavior is not consistent with an exit pathway involving desorption followed by aqueous diffusion to acceptors nor with a simple one-step collision mechanism. Rather, it is that predicted for an activation-collision mechanism in which the reversible partial projection of cholesterol molecules out of the bilayer precedes their collisional capture by cyclodextrin. Because the entire membrane pool was transferred in a single first-order process under all conditions, we infer that the transbilayer diffusion (flip-flop) of cholesterol must have proceeded faster than its exit, i.e., with a half-time of <1 s at 37 degrees C.

  1. 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

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

    PubMed

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

    2008-12-01

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

  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.

  4. 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.

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

    PubMed

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

    2009-11-01

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

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

    PubMed

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

    2006-08-01

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

  7. 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.

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

    PubMed

    Zhu, A

    2000-04-01

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

  9. Respiratory Impairment after Early Red Cell Transfusion in Pediatric Patients with ALI/ARDS.

    PubMed

    Rajasekaran, Surender; Sanfilippo, Dominic; Shoemaker, Allen; Curtis, Scott; Zuiderveen, Sandra; Ndika, Akunne; Stoiko, Michael; Hassan, Nabil

    2012-01-01

    Introduction. In the first 48 hours of ventilating patients with acute lung injury (ALI)/acute respiratory distress syndrome (ARDS), a multipronged approach including packed red blood cell (PRBC) transfusion is undertaken to maintain oxygen delivery. Hypothesis. We hypothesized children with ALI/ARDS transfused within 48 hours of initiating mechanical ventilation would have worse outcome. The course of 34 transfused patients was retrospectively compared to 45 nontransfused control patients admitted to the PICU at Helen DeVos Children's Hospital between January 1st 2008 and December 31st 2009. Results. Mean hemoglobin (Hb) prior to transfusion was 8.2 g/dl compared to 10.1 g/dl in control. P/F ratio decreased from 135.4 ± 7.5 to 116.5 ± 8.8 in transfused but increased from 148.0 ± 8.0 to 190.4 ± 17.8 (P < 0.001) in control. OI increased in the transfused from 11.7 ± 0.9 to 18.7 ± 1.6 but not in control. Ventilator days in the transfused were 15.6 ± 1.7 versus 9.5 ± 0.6 days in control (P < 0.001). There was a trend towards higher rates of MODS in transfused patients; 29.4% versus 17.7%, odds ratio 1.92, 95% CI; 0.6-5.6 Fisher exact P < 0.282. Conclusion. This study suggests that early transfusions of patients with ALI/ARDS were associated with increased ventilatory needs.

  10. Insights into red blood cell storage lesion: Toward a new appreciation.

    PubMed

    Antonelou, Marianna H; Seghatchian, Jerard

    2016-12-01

    Red blood cell storage lesion (RSL) is a multifaceted biological phenomenon. It refers to deterioration in RBC quality that is characterized by lethal and sub-lethal, reversible and irreversible defects. RSL is influenced by prestorage variables and it might be associated with variable clinical outcomes. Optimal biopreservation conditions are expected to offer maximum levels of RBC survival and acceptable functionality and bioreactivity in-bag and in vivo; consequently, full appraisal of RSL requires understanding of how RSL changes interact with each other and with the recipient. Recent technological innovation in MS-based omics, imaging, cytometry, small particle and systems biology has offered better understanding of RSL contributing factors and effects. A number of elegant in vivo and in vitro studies have paved the way for the identification of quality control biomarkers useful to predict RSL profile and posttransfusion performance. Moreover, screening tools for the early detection of good or poor "storers" and donors have been developed. In the light of new perspectives, storage time is not the touchstone to rule on the quality of a packed RBC unit. At least by a biochemical standpoint, the metabolic aging pattern during storage may not correspond to the currently fresh/old distinction of stored RBCs. Finally, although each unit of RBCs is probably unique, a metabolic signature of RSL across storage variables might exist. Moving forward from traditional hematologic measures to integrated information on structure, composition, biochemistry and interactions collected in bag and in vivo will allow identification of points for intervention in a transfusion meaningful context.

  11. Respiratory Impairment after Early Red Cell Transfusion in Pediatric Patients with ALI/ARDS

    PubMed Central

    Rajasekaran, Surender; Sanfilippo, Dominic; Shoemaker, Allen; Curtis, Scott; Zuiderveen, Sandra; Ndika, Akunne; Stoiko, Michael; Hassan, Nabil

    2012-01-01

    Introduction. In the first 48 hours of ventilating patients with acute lung injury (ALI)/acute respiratory distress syndrome (ARDS), a multipronged approach including packed red blood cell (PRBC) transfusion is undertaken to maintain oxygen delivery. Hypothesis. We hypothesized children with ALI/ARDS transfused within 48 hours of initiating mechanical ventilation would have worse outcome. The course of 34 transfused patients was retrospectively compared to 45 nontransfused control patients admitted to the PICU at Helen DeVos Children's Hospital between January 1st 2008 and December 31st 2009. Results. Mean hemoglobin (Hb) prior to transfusion was 8.2 g/dl compared to 10.1 g/dl in control. P/F ratio decreased from 135.4 ± 7.5 to 116.5 ± 8.8 in transfused but increased from 148.0 ± 8.0 to 190.4 ± 17.8 (P < 0.001) in control. OI increased in the transfused from 11.7 ± 0.9 to 18.7 ± 1.6 but not in control. Ventilator days in the transfused were 15.6 ± 1.7 versus 9.5 ± 0.6 days in control (P < 0.001). There was a trend towards higher rates of MODS in transfused patients; 29.4% versus 17.7%, odds ratio 1.92, 95% CI; 0.6–5.6 Fisher exact P < 0.282. Conclusion. This study suggests that early transfusions of patients with ALI/ARDS were associated with increased ventilatory needs. PMID:22957223

  12. Role molecular signaling pathways in changes of red blood cell deformability.

    PubMed

    Muravyov, Alexei V; Tikhomirova, Irina A

    2013-01-01

    This study was designed to investigate the dependency of the red blood cell deformability upon activation of extra- and intracellular signaling pathways. Exposures of red blood cells (RBCs) to catecholamines and to insulin led to positive change in the RBC deformability. When forskolin, a stimulator of adenylyl cyclase (AC), was added to RBC suspension, the RBC deformability was increased. Somewhat more significant deformability rise appeared after RBC incubation with dB-AMP. The inhibitors of phosphodiesterase (PDE) activity increased red cell deformability. These results revealed a considerable role of the AC-cAMP signaling system in the regulation of red blood cell deformability. The rise of the red blood cell Ca(2+) influx, stimulated by mechanical loading or A23187 was accompanied by a marked lowering of RBC deformability. At the same time blocking of Ca(2+) entry into RBC by verapamil or Ca(2+) chelating by EGTA led to significant deformability rise. The comparison of the effect of the different protein kinases on the red blood cell deformability showed that it was altered more considerable under PKA activation by forskolin or dB-cAMP than by other protein kinases. There was a lesser but quite statistically significant effect of tyrosine protein kinase (TPK) on RBC microrheology. Whereas the microrheological effect of PKC was not so considerable. The problem of the short-term regulation of red blood cell microrheology is examined. The latter includes: the modes of activation of extra- and intracellular molecular signaling pathways, ligand - receptor interaction, second messengers, membrane protein phosphorylation. On the whole the total data clearly show that the red cell deformability changes are connected with activation of different extra - and intracellular signaling pathways. It seems reasonable to suppose that red blood cell deformability changes were mainly associated with activation of the AC-cAMP-PKA pathway, and with decrease of Ca(2+) entry into

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

    PubMed

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

    2016-06-10

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

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

    PubMed

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

    2013-04-01

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

  15. Pseudohyperkalaemia and pseudomacrocytosis caused by inherited red-cell disorders of the 'hereditary stomatocytosis' group.

    PubMed

    Chetty, M C; Stewart, G W

    2001-01-01

    Unusual dominantly inherited conditions of the red cell, collected under the generic title 'hereditary stomatocytosis and allied disorders', exist, in which the red cell 'leaks' the univalent cations sodium (Na+) and potassium (K+). In some kindreds with these disorders, bizarre temperature effects can occur that have profound effects on the way in which the cells behave when removed from the body and cooled to either room or refrigerator temperatures. In some types, the cells lose K+ at room temperature, giving rise to pseudohyperkalaemia; in others, this occurs in concert with swelling of the red cell and pseudomacrocytosis. In some of these conditions, a red-cell abnormality is clearly demonstrated by the presence of haemolytic anaemia; however, routine haematology can be virtually normal in the milder versions. All are inherited as dominants, although new mutations can be seen.

  16. Long term stable deep red light-emitting electrochemical cells based on an emissive, rigid cationic Ir(iii) complex

    DOE PAGES

    Namanga, Jude E.; Gerlitzki, Niels; Mallick, Bert; ...

    2017-02-17

    Here, the new cationic iridium complex [Ir(bzq)2(biq)][PF6] (bzq = benzo[h]quinolinato and biq = 2,2'-biquinoline) has been synthesized for application as an emitter in light emitting electrochemical cells (LECs). The molecular structure and crystal packing of this complex were established by single X-ray diffraction (SXRD). The electrochemical and photophysical properties of the complex were examined to determine the frontier orbital energies as well as the optical transitions that led to photoemission. The complex was found to emit at 644 nm and 662 nm for powder and thin films, respectively. A high powder photoluminescence quantum yield of 25% was determined, which ismore » attributed to a reduction in vibrational modes of the complex due to the use of the rigid cyclometalated (C^N) bzq ligand. A LEC with [Ir(bzq)2(biq)][PF6] as the emitter was fabricated which showed a deep red emission (662 nm) with a luminance of 33.65 cd m–2, yielding a current efficiency of 0.33 cd A–1 and a power efficiency of 0.2 lm W–1. Most importantly, the LEC based on [Ir(bzq)2(biq)][PF6] demonstrated a lifetime of 280 hours which is among the longest device lifetimes reported for any deep red light emitting LEC.« less

  17. 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.

  18. The application of KillerRed for acute protein inactivation in living cells

    PubMed Central

    Jarvela, Timothy S.; Linstedt, Adam D.

    2017-01-01

    Generating loss of protein function is a powerful investigatory tool particularly if carried out at a physiologically relevant timescale in a live-cell fluorescent imaging experiment. KillerRed mediated chromophore assisted light inactivation (CALI) uses genetic encoding for specificity and light for acute inactivation that can also be spatially restricted. This unit provides protocols for setting up and carrying out properly controlled KillerRed experiments during live-cell imaging of cultured cells. PMID:24984963

  19. Red Blood Cell Alloimmunization in Sickle Cell Disease: Listen to Your Ancestors

    PubMed Central

    Campbell-Lee, Sally A.; Kittles, Rick A.

    2014-01-01

    Summary Red blood cell (RBC) alloimmunization occurs in approximately 30% of transfused sickle cell disease patients compared to 2–5% of all transfusion recipients. Because RBC transfusion is an important part of therapy in sickle cell disease, the need for additional antigen matching once alloimmunization occurs is problematic and leads to therapeutic limitations. Thus, identification of risk factors would benefit this patient population. Genome-wide analyses, in particular, methods which take into account genetic ancestry such as admixture mapping, could identify molecular markers which could be used to identify immune responders to transfusion. PMID:25670930

  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.

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

    PubMed

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

    2014-04-01

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

  2. 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…

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. The acute effects of nifedipine on red cell deformability in angina pectoris.

    PubMed Central

    Waller, D G; Nicholson, H P; Roath, S

    1984-01-01

    In a randomised double-blind study, the effects on red cell deformability of a single sublingual dose of nifedipine were compared with placebo in eight patients with stable angina pectoris. Red cell deformability, measured by filtration and centrifugation techniques, was significantly increased at rest in all eight patients 1 h after nifedipine, while no change occurred after placebo. The improvement in deformability after nifedipine was maintained at the end of a period of exercise and unchanged from resting values after placebo. The results suggest that the increased deformability of red cells after nifedipine could contribute to the therapeutic effects of the drug in myocardial ischaemia. PMID:6704282

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

    PubMed

    Li, Taihang; Jing, Xiabin; Huang, Yubin

    2011-07-07

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

  10. 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.

  11. The effect of cyanide on the uptake of gold by red blood cells.

    PubMed

    Graham, G G; Haavisto, T M; Jones, H M; Champion, G D

    1984-04-15

    Cyanide markedly increased the rate of uptake of gold by red blood cells when incubated with sodium aurothiomalate, a polymeric gold complex. Thiocyanate had no significant effect on gold uptake. The effect of cyanide was demonstrated to be due to the conversion of aurothiomalate to the complexion, aurocyanide, which is rapidly taken up by red blood cells. At a low ratio (1:20) of cyanide to aurothiomalate, cyanide appeared to act as a shuttle to carry gold into red blood cells. Tobacco smoking is known to increase the concentrations of gold in red blood cells in patients treated with aurothiomalate. The present data indicate that this effect of smoking is most likely due to cyanide inhaled in tobacco smoke and not to thiocyanate, a circulating metabolite of cyanide. An effect of cyanide on the uptake of polymeric gold complexes to target cells such as polymorphonuclear leukocytes and monocytes is suggested.

  12. Simulated Red Blood Cell Motion in Microvessel Bifurcations: Effects of Cell-Cell Interactions on Cell Partitioning

    PubMed Central

    Barber, Jared O.; Restrepo, Juan M.; Secomb, Timothy W.

    2013-01-01

    Partitioning of red blood cell (RBC) fluxes between the branches of a diverging microvessel bifurcation is generally not proportional to the flow rates, as RBCs preferentially enter the higher-flow branch. A two-dimensional model for RBC motion and deformation is used to investigate the effects of cell-cell mechanical interactions on RBC partitioning in bifurcations. The RBC membrane and cytoplasm are represented by sets of viscoelastic elements immersed in a low Reynolds number flow. Several types of two-cell interactions that can affect partitioning are found. In the most frequent interactions, a `trade-off' occurs, in which a cell entering one branch causes a following cell to enter the other branch. Other types of interactions include `herding,' where the leading cell is caused to enter the same branch as the following cell, and `following,' where the trailing cell is caused to enter the same branch as the leading cell. The combined effect of these cell-cell interactions is a tendency towards more uniform partitioning, which results from the trade-off effect but is reduced by the herding and following effects. With increasing hematocrit, the frequency of interactions increases, and more uniform partitioning results. This prediction is consistent with experimental observations on how hematocrit affects RBC partitioning. PMID:23555330

  13. 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

    2012-05-09

    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.

  14. 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.

  15. 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

  16. What is antibody-mediated pure red cell aplasia (PRCA)?

    PubMed

    Casadevall, Nicole

    2005-05-01

    Antibody (Ab)-mediated pure red cell aplasia (PRCA) is an immunological pathology associated with the production of neutralizing Abs that inhibit the erythropoietic activity of endogenous erythropoietin (EPO) and recombinant erythropoiesis-stimulating agents (ESAs). Although this disorder occurs very rarely, the number of reported cases has increased dramatically in recent years, predominantly in patients with chronic kidney disease (CKD)-associated anaemia receiving subcutaneous (s.c.) injections of one particular formulation of recombinant epoetin-alpha. This disorder is differentiated from classic forms of PRCA that are caused by chemical toxaemia (i.e. erythroblastopenia induced by chemical compounds), lymphoproliferative neoplasms, thymoma, human parvovirus B19 and certain autoimmune disorders. Patients with Ab-mediated PRCA develop resistance to EPO and severe anaemia that follows a period of successful erythropoietic response, and exhibit characteristic decreases in blood haemoglobin (Hb) level and in the number of circulating reticulocytes. However, it is not yet possible to predict which patients will develop PRCA or when in the course of their treatments PRCA may develop. Laboratory confirmation of Ab-mediated PRCA requires bone marrow examination demonstrating few or no erythroid precursors and the presence of serum anti-EPO Abs using a validated assay. These neutralizing anti-EPO Abs recognize the protein core of the EPO molecule; carbohydrate groups on EPO can affect the binding of Abs but are themselves not immunological determinants. Animal models are being developed to increase further our understanding of the immunological mechanisms underlying the onset and progression of Ab-mediated PRCA.

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

    PubMed

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

    2012-03-01

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

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

    PubMed Central

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

    2014-01-01

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

  19. Double red cell concentrates -in vitro quality after delayed refrigeration.

    PubMed

    Thomas, S; Bekoe, Y; Uddin, S; Beard, M; Cardigan, R

    2010-10-01

    Automated collection of red cell concentrates (RCC) presents a number of potential advantages to donors, blood services and recipients, and allows the collection of finished components from sites that are remote from a blood centre. However, data are lacking on how long the collected RCC may be stored at ambient temperature prior to their final storage at 4 °C. In this study, the Haemonetics Cymbal device was used to collect RCC using citrate, phosphate and dextrose (CPD-50) anticoagulant. A total of 10 procedures each yielded two leucodepleted RCC in saline, adenine, glucose and mannitol (SAGM) additive solution. One of each pair of RCC was kept warm in an insulated transport bag for 8 h and the other for 6 h. In vitro assessments of the quality of the RCC were made during subsequent 42-day storage of the RCC at 2-6 °C, and compared with reference data. All collected RCC were within UK and European limits for volume, haematocrit and haemoglobin content. Haemolysis was within specification at Day 42 and was no different in RCC held warm for 6 or 8 hours, but tended to be higher than reference data from whole blood derived RCC. ATP, 2,3 DPG and supernatant potassium levels were all similar in RCC held warm for 6 or 8 hours and reference data. We conclude that the Cymbal device may be used to collect two RCC in SAGM, and the in vitro assessment indicates that RCC may be stored without refrigeration for up to 8 h following collection, prior to final storage at 4 °C.

  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. 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.

  2. 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.

  3. 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.

  4. Controlling Morphology and Molecular Packing of Alkane Substituted Phthalocyanine Blend Bulk Heterojunction Solar Cells.

    PubMed

    Jurow, Matthew J; Hageman, Brian A; Dimasi, Elaine; Nam, Chang-Yong; Pabon, Cesar; Black, Charles T; Drain, Charles Michael

    2013-02-07

    Systematic changes in the exocyclic substiution of core phthalocyanine platform tune the absorption properties to yield commercially viable dyes that function as the primary light absorbers in organic bulk heterojunction solar cells. Blends of these complementary phthalocyanines absorb a broader portion of the solar spectrum compared to a single dye, thereby increasing solar cell performance. We correlate grazing incidence small angle x-ray scattering structural data with solar cell performance to elucidate the role of nanomorphology of active layers composed of blends of phthalocyanines and a fullerene derivative. A highly reproducible device architecture is used to assure accuracy and is relevant to films for solar windows in urban settings. We demonstrate that the number and structure of the exocyclic motifs dictate phase formation, hierarchical organization, and nanostructure, thus can be employed to tailor active layer morphology to enhance exciton dissociation and charge collection efficiencies in the photovoltaic devices. These studies reveal that disordered films make better solar cells, short alkanes increase the optical density of the active layer, and branched alkanes inhibit unproductive homogeneous molecular alignment.

  5. 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 ...

  6. Optical evaluation of red blood cell geometry using micropipette aspiration.

    PubMed

    Engström, K G; Möller, B; Meiselman, H J

    1992-01-01

    Although red blood cell (RBC) geometry has been extensively studied by micropipette aspiration, the small size of RBC and pipettes vs. the optical resolution of light microscopy suggests the need to consider potential errors. The present study addressed such difficulties and investigated four specific problems: (1) use of exact equations to calculate RBC membrane area and volume; (2) calibration of the pipette internal diameter (PID); (3) correction for a noncylindrical pipette barrel; (4) diffraction distortion of the RBC image. The observed PID represents a cylinder lens enlargement that can be theoretically derived from the glass/buffer refractive index ratio (1.49/1.33 = 1.12). This enlargement was experimentally confirmed by: (1) studying pipettes bent to allow measurement through the barrel (horizontal) and at the orifice (vertical), with a resulting diameter ratio of 1.12 +/- 0.01; (2) and by replacing the surrounding buffer with immersion oil and hence abolishing the lens phenomenon (ratio = 1.12 +/- 0.02). In addition, use of aspirated oil droplets demonstrated a 3.2 +/- 0.2% error when the PID is focused at a sharp, maximum diameter. The average pipette cone angle was 1.49 +/- 0.09 degrees and varied considerably with pipette pulling procedures; calculated tongue geometry inside the pipette was affected by the noncylindrical pipette barrel. The RBC diffraction error, demonstrated by touching two aspirated cells held by opposing pipettes, was 0.091 +/- 0.002 microns. The PID, cone angle, and diffraction artifacts significantly (p < 0.001) affected calculated RBC geometry (average errors up to 5.4% for area and 9.6% for volume). Two new methods to calculate, rather than directly measure, the PID from images of a single RBC, during either osmotic or pressure manipulation, were evaluated; the osmotic method closely predicted the PID, whereas the pressure method markedly underestimated the PID. Our results thus confirm the need to consider the above

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

    PubMed

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

    2014-10-01

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

  8. 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.

  9. 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

  10. 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.

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

    DOEpatents

    Bitensky, M.W.; Yoshida, Tatsuro

    1997-04-29

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

  12. New frontiers in transfusion biology: Identification and significance of mediators of morbidity and mortality in stored red cell concentrates

    PubMed Central

    Grimshaw, Katie; Sahler, Julie; Spinelli, Sherry L.; Phipps, Richard P.; Blumberg, Neil

    2011-01-01

    Red cell transfusions are associated with inflammation and thrombosis, both arterial and venous, the mechanisms of which are not understood. Although a necessary life saving procedure in modern medicine, transfusions have rarely been subjected to modern assessments of efficacy and safety, including randomized trials. Storage of red blood cells induces changes, including the release of free hemoglobin and the accumulation of biologically active soluble mediators and microparticles. These mediators likely play a direct role in the inflammatory and pro-thrombotic properties of red cell transfusions. Methods such as leukoreduction, washing of red cells and rejuvenation may improve the quality of red cell transfusions. PMID:21496049

  13. From Fullerene-Polymer to All-Polymer Solar Cells: The Importance of Molecular Packing, Orientation, and Morphology Control.

    PubMed

    Kang, Hyunbum; Lee, Wonho; Oh, Jiho; Kim, Taesu; Lee, Changyeon; Kim, Bumjoon J

    2016-11-15

    All-polymer solar cells (all-PSCs), consisting of conjugated polymers as both electron donor (PD) and acceptor (PA), have recently attracted great attention. Remarkable progress has been achieved during the past few years, with power conversion efficiencies (PCEs) now approaching 8%. In this Account, we first discuss the major advantages of all-PSCs over fullerene-polymer solar cells (fullerene-PSCs): (i) high light absorption and chemical tunability of PA, which affords simultaneous enhancement of both the short-circuit current density (JSC) and the open-circuit voltage (VOC), and (ii) superior long-term stability (in particular, thermal and mechanical stability) of all-PSCs due to entangled long PA chains. In the second part of this Account, we discuss the device operation mechanism of all-PSCs and recognize the major challenges that need to be addressed in optimizing the performance of all-PSCs. The major difference between all-PSCs and fullerene-PSCs originates from the molecular structures and interactions, i.e., the electron transport ability in all-PSCs is significantly affected by the packing geometry of two-dimensional PA chains relative to the electrodes (e.g., face-on or edge-on orientation), whereas spherically shaped fullerene acceptors can facilitate isotropic electron transport properties in fullerene-PSCs. Moreover, the crystalline packing structures of PD and PA at the PD-PA interface greatly affect their free charge carrier generation efficiencies. The design of PA polymers (e.g., main backbone, side chain, and molecular weight) should therefore take account of optimizing three major aspects in all-PSCs: (1) the electron transport ability of PA, (2) the molecular packing structure and orientation of PA, and (3) the blend morphology. First, control of the backbone and side-chain structures, as well as the molecular weight, is critical for generating strong intermolecular assembly of PA and its network, thus enabling high electron transport ability

  14. 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.

  15. 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.

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

    PubMed

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

    2014-05-01

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

  17. 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.

  18. Evaluation of a volumetric intravenous fluid infusion pump for transfusion of blood components containing red cells.

    PubMed

    Thompson, H W; Lasky, L C; Polesky, H F

    1986-01-01

    A method was devised to evaluate the suitability of an infusion pump for transfusing components containing red cells. With simulated transfusions of units of whole blood tested before or after the expiration date there was no increase in the plasma hemoglobin level in pumped blood compared with blood that was put through a standard blood transfusion set. With outdated units of red cells there was an increased level of plasma hemoglobin after pumping. The increases were greatest at maximum pump rates, but were not statistically or clinically significant. The authors' evaluation indicates that this pump causes minimal damage to the red cells, although care should be exercised when rapidly transfusing red cells with high hematocrit values.

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

    PubMed

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

    2017-01-04

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

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

    PubMed Central

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

    2017-01-01

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

  1. Neutral red uptake assay for the estimation of cell viability/cytotoxicity.

    PubMed

    Repetto, Guillermo; del Peso, Ana; Zurita, Jorge L

    2008-01-01

    The neutral red uptake assay provides a quantitative estimation of the number of viable cells in a culture. It is one of the most used cytotoxicity tests with many biomedical and environmental applications. It is based on the ability of viable cells to incorporate and bind the supravital dye neutral red in the lysosomes. Most primary cells and cell lines from diverse origin may be successfully used. Cells are seeded in 96-well tissue culture plates and are treated for the appropriate period. The plates are then incubated for 2 h with a medium containing neutral red. The cells are subsequently washed, the dye is extracted in each well and the absorbance is read using a spectrophotometer. The procedure is cheaper and more sensitive than other cytotoxicity tests (tetrazolium salts, enzyme leakage or protein content). Once the cells have been treated, the assay can be completed in <3 h.

  2. 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.

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

    NASA Astrophysics Data System (ADS)

    Noguchi, H.

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

  4. 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.

  5. Molecular matching of red blood cells is superior to serological matching in sickle cell disease patients

    PubMed Central

    da Costa, Daiane Cobianchi; Pellegrino Jr, Jordão; Guelsin, Gláucia Andréia Soares; Ribeiro, Karina Antero Rosa; Gilli, Simone Cristina Olenscki; Castilho, Lilian

    2013-01-01

    Objective To evaluate the usefulness of DNA methods to provide a means to precisely genotypically match donor blood units for the antigen-negative type of 35 sickle cell disease patients. Methods Red blood cell units were investigated for ABO, D, C, c, E, e, K, Fya, Fyb, Jka, Jkb, S, s, Dia and RH variants by performing a molecular array (Human Erythrocyte Antigen BeadChipTM, BioArray Solutions), polymerase chain reaction followed by restriction fragment length polymorphism analysis and sequencing of patient samples and donor units that had been serologically matched based on the ABO, Rh and K phenotypes and the presence of antibodies. Results Matches for 21 of 35 sickle cell disease patients presented discrepancies or mismatches for multiple antigens between the genotype profile and the antigen profile of their serologically-matched blood units. The main discrepancies or mismatches occurred in the RH, FY, JK and MNS systems. Eight Rh alloimmunized patients presented RHD and RHCE variants that had not been serologically identified. According to these results better matches were found for the patients with genotyped units and the patients benefited as shown by better in vivo red blood cell survival. Conclusion Molecular matching is superior to serological matching in sickle cell disease patients, decreasing the risk of transfusion reactions, especially delayed transfusion reactions to existing alloantibodies and preventing alloimmunization. PMID:23580882

  6. Genetic parameters for faecal egg count, packed-cell volume and body-weight in Santa Inês lambs

    PubMed Central

    2009-01-01

    Worm infection is one of the main factors responsible for economic losses in sheep breeding in Brazil. Random regression analysis was used to estimate genetic parameters for the factors faecal egg-count (FEC), packed-cell volume (PCV) and body weight (BW) in Santa Inês lambs. Data from 119 female, offspring of nine rams, were collected between December, 2005 and December, 2006, from the experimental flock of Embrapa Tabuleiros Costeiros, the Brazilian Agricultural Research Corporation located in Frei Paulo, SE, Brazil. After weaning, females were drenched until the faecal egg count had dropped to zero. Two natural challenges were undertaken. FEC heritability was extremely variable, this increasing from 0.04 to 0.27 in the first challenge and from 0.01 to 0.52 during the second. PCV heritability peaks were 0.31 and 0.12 in the first and second challenges, respectively. In the second challenge, BW heritability was close to 0.90. The genetic correlations among these traits did not differ from zero. There is the possibility of increasing parasite resistance in Santa Inês by selecting those animals with lower FEC. Selection to increase resistance will not adversely affect lamb-growth, although lambs with a slow growth-rate may be more susceptible to infection. PMID:21637682

  7. Genetic parameters for faecal egg count, packed-cell volume and body-weight in Santa Inês lambs.

    PubMed

    Lôbo, Raimundo N B; Vieira, Luiz S; de Oliveira, Amaury A; Muniz, Evandro N; da Silva, José M

    2009-04-01

    Worm infection is one of the main factors responsible for economic losses in sheep breeding in Brazil. Random regression analysis was used to estimate genetic parameters for the factors faecal egg-count (FEC), packed-cell volume (PCV) and body weight (BW) in Santa Inês lambs. Data from 119 female, offspring of nine rams, were collected between December, 2005 and December, 2006, from the experimental flock of Embrapa Tabuleiros Costeiros, the Brazilian Agricultural Research Corporation located in Frei Paulo, SE, Brazil. After weaning, females were drenched until the faecal egg count had dropped to zero. Two natural challenges were undertaken. FEC heritability was extremely variable, this increasing from 0.04 to 0.27 in the first challenge and from 0.01 to 0.52 during the second. PCV heritability peaks were 0.31 and 0.12 in the first and second challenges, respectively. In the second challenge, BW heritability was close to 0.90. The genetic correlations among these traits did not differ from zero. There is the possibility of increasing parasite resistance in Santa Inês by selecting those animals with lower FEC. Selection to increase resistance will not adversely affect lamb-growth, although lambs with a slow growth-rate may be more susceptible to infection.

  8. 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.

  9. 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.

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

    PubMed

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

    2014-06-01

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

  11. 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.

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

    PubMed

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

    2014-01-01

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

  13. Acute and chronic influence of temperature on red blood cell anion exchange.

    PubMed

    Jensen, F B; Wang, T; Brahm, J

    2001-01-01

    Unidirectional (36)Cl(-) efflux via the red blood cell anion exchanger was measured under Cl(-) self-exchange conditions (i.e. no net flow of anions) in rainbow trout Oncorhynchus mykiss and red-eared freshwater turtle Trachemys scripta to examine the effects of acute temperature changes and acclimation temperature on this process. We also evaluated the possible adaptation of anion exchange to different temperature regimes by including our previously published data on other animals. An acute temperature increase caused a significant increase in the rate constant (k) for unidirectional Cl(-) efflux in rainbow trout and freshwater turtle. After 3 weeks of temperature acclimation, 5 degrees C-acclimated rainbow trout showed only marginally higher Cl(-) transport rates than 15 degrees C-acclimated trout when compared at the same temperature. Apparent activation energies for red blood cell Cl(-) exchange in trout and turtle were lower than values reported in endothermic animals. The Q(10) for red blood cell anion exchange was 2.0 in trout and 2.3 in turtle, values close to those for CO(2) excretion, suggesting that, in ectothermic animals, the temperature sensitivity of band-3-mediated anion exchange matches the temperature sensitivity of CO(2) transport (where red blood cell Cl(-)/HCO(3)(-) exchange is a rate-limiting step). In endotherms, such as man and chicken, Q(10) values for red blood cell anion exchange are considerably higher but are no obstacle to CO(2) transport, because body temperature is normally kept constant at values at which anion exchange rates are high. When compared at constant temperature, red blood cell Cl(-) permeability shows large differences among species (trout, carp, eel, cod, turtle, alligator, chicken and man). Cl(-) permeabilities are, however, remarkable similar when compared at preferred body temperatures, suggesting an appropriate evolutionary adaptation of red blood cell anion exchange function to the different thermal niches occupied

  14. Use of /sup 75/Se-labeled methionine to study the sequestration of senescent red blood cells

    SciTech Connect

    Smedsrod, B.; Aminoff, D.

    1985-01-01

    Labeling red blood cells with Na/sub 2//sup 51/CrO/sub 4/ enabled us to study certain aspects of red cell survival and sequestration from the circulation. As a random labeling procedure, however, the /sup 51/Cr method has certain limitations. Therefore, we developed a cohort labeling method using /sup 75/Se-methionine as a two-rat procedure. This gives a clear pulse-labeled population of rat red cells to study the dynamics of sequestration. With this labeling procedure, it was possible to demonstrate that 1) there is an increase in the density of red cells with age, 2) a significant sequestration of red cells from the circulation is apparent at the end of 48 days and essentially is complete at the end of 60 days, 3) there is a corresponding uptake of senescent red cells in the spleen, which peaks at 55 days, and 4) the 60-day end point is sharper and is more definitive when the specific activity (cpm per red blood cell) of the labeled red cells in the spleen is compared to that of the red cells still in the circulation. Asialo red cells, obtained by removal of sialic acid with sialidase, frequently have been used as a model for the study of sequestration of senescent red cells. With the technique herein described, it was possible to show that while asialo red cells will inhibit the uptake of labeled asialo red cells, they have no effect on the sequestration of senescent red cells. Presumably, different sites and mechanisms of sequestration are involved.

  15. 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.

  16. Malaria parasites and red cell variants: when a house is not a home

    PubMed Central

    Taylor, Steve M.; Fairhurst, Rick M.

    2014-01-01

    Purpose of review Multiple red cell variants are known to confer protection from malaria. Here we review advances in identifying new variants that modulate malaria risk and in defining molecular mechanisms that mediate malaria protection. Recent findings New red cell variants, including an innate variant in the red cell’s major Ca2+ pump and the acquired state of iron deficiency, have been associated with protection from clinical falciparum malaria. The hemoglobin (Hb) mutants HbC and HbS – known to protect carriers from severe falciparum malaria – enhance parasite passage to mosquitoes and may promote malaria transmission. At the molecular level, substantial advances have been made in understanding the impact of HbS and HbC upon the interactions between host microRNAs and Plasmodium falciparum protein translation; remodeling of red cell cytoskeletal components and transport of parasite proteins to the red cell surface; and chronic activation of the human innate immune system which induces tolerance to blood-stage parasites. Several polymorphisms have now been associated with protection from clinical vivax malaria or reduced P. vivax density, including Southeast Asian ovalocytosis and two common forms of glucose-6-phosphate dehydrogenase deficiency. Summary Red cell variants that modulate malaria risk can serve as models to identify clinically relevant mechanisms of pathogenesis, and thus define parasite and host targets for next-generation therapies. PMID:24675047

  17. 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.

  18. 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

    2016-01-07

    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.

  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. A Stability Result on the Orientation of Red Blood Cells in the Venule Network

    NASA Astrophysics Data System (ADS)

    Munganga, J. M. W.; Maritz, R.

    2011-06-01

    We model blood as a non-Newtonian fluid. Red blood cells, white blood cells and platelets immersed in plasma, are modeled as a suspension where the particles, erythrocyte cell aggregates, are assumed to be in the shape of a rigid cylinder. The orientation of these particles is affected by various factors. In this article we look at the effect of magnetic fields on the orientation of these red blood cell particles. A proof of stability of solutions is given, under the assumption that the body is subjected to the effect of magnetic fields.

  1. Small-angle X-ray scattering probe of intermolecular interaction in red blood cells

    NASA Astrophysics Data System (ADS)

    Liu, Guan-Fen; Wang, We-Jia; Xu, Jia-Hua; Dong, Yu-Hui

    2015-03-01

    With high concentrations of hemoglobin (Hb) in red blood cells, self-interactions among these molecules could increase the propensities of their polymerization and aggregation. In the present work, high concentration Hb in solution and red blood cells were analyzed by small-angle X-ray scattering. Calculation of the effective structure factor indicates that the interaction of Hb molecules is the same when they are crowded together in both the cell and physiological saline. The Hb molecules stay individual without the formation of aggregates and clusters in cells. Supported by National Basic Research Program of China (2009CB918600) and National Natural Science Foundation of China (10979005)

  2. Extracts from red muscadine and cabernet sauvignon wines induce cell death in MOLT-4 human leukemia cells.

    PubMed

    Mertens-Talcott, Susanne U; Percival, Susan S; Talcott, Stephen T

    2008-06-01

    Red wine contains a diversity of polyphenolic compounds that exert beneficial health effects including anti-cancer effects. This trial evaluated the anti-proliferative potential of red muscadine (Vitis rotundifolia) and red cabernet sauvignon (Vitis vinifera) wines in cell culture. Chemical properties of wines were determined by HPLC-PDA analysis and concentrated extracts of each wine were evaluated before and after glycosidic hydrolysis in MOLT-4 leukemia cells. Cell growth and the induction of apoptosis were evaluated after exposure to various extract dilutions. Wine extracts reduced cell viability up to 68% and cell numbers up to 50% after 48h with muscadine extracts being more effective than cabernet sauvignon. Caspase-3 activity was induced similarly by all extracts in a dose dependent manner. Cell cycle arrest in the G2/M phase was observed for both muscadine and the non-hydrolyzed cabernet sauvignon extract. Collectively, extracts from both wines exerted anti-cancer effects in leukemia cells.

  3. Incorporation of fluorescein conjugated function-spacer-lipid constructs into the red blood cell membrane facilitates detection of labeled cells for the duration of ex-vivo storage.

    PubMed

    Ki, Katrina K; Flower, Robert L; Faddy, Helen M; Dean, Melinda M

    2016-02-01

    The contribution of ex-vivo storage duration of packed red blood cells (PRBC) to patient outcomes and transfusion-related immunomodulation (TRIM) remains a broadly debated area in transfusion medicine. Kode™ Technology with fluorescein conjugated function-spacer-lipid (FSL-FLRO4) constructs is a tool that can aid in-vitro visualization and tracking of red blood cells (RBC) during routine storage. FSL-FLRO4 is incorporated into the RBC membrane without altering cell function. In this study, we explore the suitability of this technology to label clinical grade PRBC and to determine if the label would be retained during ex-vivo storage. Firstly, to confirm feasibility and assess the limit of detection of FSL-FLRO4 on PRBC at date of expiry (42 days post-collection), we tracked the binding of FSL-FLRO4 on PRBC at weekly intervals during routine storage. Over the time course, all cells remained labelled with FSL-FLRO4, although a decrease in the intensity of labelling was observed (P<0.0001). We then further investigated differences in FSL-FLRO4 labelling during RBC storage by labelling separated light-young and dense-old RBC from the same PRBC unit. There were no differences in the capacity of FSL-FLRO4 to label these different RBC subsets. Together, these data demonstrate that FSL-FLRO4 is a suitable reagent for labelling PRBC at any point during routine storage. This technology will facilitate the development of immunoassays and transfusion models focused on addressing the mechanisms involved in TRIM.

  4. 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.

  5. 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.

  6. Pattern formations and optimal packing.

    PubMed

    Mityushev, Vladimir

    2016-04-01

    Patterns of different symmetries may arise after solution to reaction-diffusion equations. Hexagonal arrays, layers and their perturbations are observed in different models after numerical solution to the corresponding initial-boundary value problems. We demonstrate an intimate connection between pattern formations and optimal random packing on the plane. The main study is based on the following two points. First, the diffusive flux in reaction-diffusion systems is approximated by piecewise linear functions in the framework of structural approximations. This leads to a discrete network approximation of the considered continuous problem. Second, the discrete energy minimization yields optimal random packing of the domains (disks) in the representative cell. Therefore, the general problem of pattern formations based on the reaction-diffusion equations is reduced to the geometric problem of random packing. It is demonstrated that all random packings can be divided onto classes associated with classes of isomorphic graphs obtained from the Delaunay triangulation. The unique optimal solution is constructed in each class of the random packings. If the number of disks per representative cell is finite, the number of classes of isomorphic graphs, hence, the number of optimal packings is also finite.

  7. 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.

  8. 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.

  9. Transdifferentiation of Human Hair Follicle Mesenchymal Stem Cells into Red Blood Cells by OCT4.

    PubMed

    Liu, Zhijing; Lu, Shi-Jiang; Lu, Yan; Tan, Xiaohua; Zhang, Xiaowei; Yang, Minlan; Zhang, Fuming; Li, Yulin; Quan, Chengshi

    2015-01-01

    Shortage of red blood cells (RBCs, erythrocytes) can have potentially life-threatening consequences for rare or unusual blood type patients with massive blood loss resulting from various conditions. Erythrocytes have been derived from human pluripotent stem cells (PSCs), but the risk of potential tumorigenicity cannot be ignored, and a majority of these cells produced from PSCs express embryonic ε- and fetal γ-globins with little or no adult β-globin and remain nucleated. Here we report a method to generate erythrocytes from human hair follicle mesenchymal stem cells (hHFMSCs) by enforcing OCT4 gene expression and cytokine stimulation. Cells generated from hHFMSCs expressed mainly the adult β-globin chain with minimum level of the fetal γ-globin chain. Furthermore, these cells also underwent multiple maturation events and formed enucleated erythrocytes with a biconcave disc shape. Gene expression analyses showed that OCT4 regulated the expression of genes associated with both pluripotency and erythroid development during hHFMSC transdifferentiation toward erythroid cells. These findings show that mature erythrocytes can be generated from adult somatic cells, which may serve as an alternative source of RBCs for potential autologous transfusion.

  10. 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.

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

    PubMed

    Kim, Hyun Ok

    2014-03-01

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

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

    PubMed

    Viallat, A; Abkarian, M

    2014-06-01

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

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

    PubMed

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

    2015-01-01

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

  14. 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.

  15. 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.

  16. Implementing mass-scale red cell genotyping at a blood center

    PubMed Central

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

    2015-01-01

    Background When problems with compatibility beyond ABO and RhD arise, currently transfusion services search their inventories and perform time-consuming serologic testing to locate antigen-negative blood. These clinically important blood group antigens can be detected reliably by red cell genotyping, which is a technology whereby DNA-based techniques are used to evaluate gene polymorphisms that determine the expression of red cell antigens. We introduced mass-scale genotyping and measured availability of genotyped blood. Study design and methods All non-Caucasian donors qualified for genotyping along with Caucasian donors who had a history of repeat donation. Mass-scale red cell genotyping, performed on an electronic interfaced open array platform, was implemented to screen blood donors for 32 SNPs that predicted 42 blood group antigens. Genotype screening results were confirmed by phenotyping, when needed for antigen-negative transfusion, prior to release of the red cell unit. Results Approximately 22,000 donors were red cell genotyped within 4 months and a total of 43,066 donors in 4 years. There were 463 discordances (0.52% of 89,596 genotypes with a phenotype). Among the 307 resolved discordances, approximate equal numbers represented historical serological or genotyping discrepancies (n=151 and n=156, respectively). In the final year of the study, an average of 29% of the daily inventory had a genotype. Conclusions Red cell genotyping of blood donors using an electronic interface created a large and stable supply of red cell units with historical genotypes. The database served the needs of antigen-negative blood requests for a large regional blood center, and allowed us to abandon screening by serology. PMID:26094790

  17. The Effect of Insulating Blood Warmer Output Tubing on the Temperature of Packed Red Blood Cells at Low Flow Rates

    DTIC Science & Technology

    1989-01-01

    appear to be a direct result of cold on the sino- arterial node and atrio- ventricular node (Tolman & Cohen, 1970). With severe hypothermia, most of...the pathophysiologic conditions appearing in moderate hypothermia will appear in an exaggerated form. The ECG deteriorates to ventricular fibrillation...falls and eventually leads to junctional rhythms, atrial flutter, premature ventricular contractions, ventricular fibrillation, and asystole (Orkin

  18. Plasma and lipids from stored packed red blood cells cause acute lung injury in an animal model.

    PubMed Central

    Silliman, C C; Voelkel, N F; Allard, J D; Elzi, D J; Tuder, R M; Johnson, J L; Ambruso, D R

    1998-01-01

    Transfusion-related acute lung injury (TRALI) is a serious complication of hemotherapy. During blood storage, lipids are generated and released into the plasma. In this study, the role of these lipids in TRALI was investigated using an isolated, perfused rat lung model. Rats were pretreated with endotoxin (LPS) or saline in vivo and the lungs were isolated, ventilated, and perfused with saline, or (a) 5% (vol/ vol) fresh human plasma, (b) plasma from stored blood from the day of isolation (D.0) or from the day of outdate (D.42), (c) lipid extracts from D.42 plasma, or (d) purified lysophosphatidylcholines. Lungs from saline or LPS-pretreated rats perfused with fresh (D.0) plasma showed no pulmonary damage as compared with saline perfused controls. LPS pretreatment/D.42 plasma perfusion caused acute lung injury (ALI) manifested by dramatic changes in both pulmonary artery pressure and edema. Incubation of LPS pre-tx rats with mibefradil, a Ca2+ channel blocker, or WEB 2170, a platelet-activating factor (PAF) receptor antagonist, inhibited ALI caused by D.42 plasma. Lung histology showed neutrophil sequestration without ALI with LPS pretreatment/saline or D.0 plasma perfusion, but ALI with LPS pretreatment/D.42 plasma perfusion, and inhibition of D.42 plasma induced ALI with WEB 2170 or mibefradil. A significant increase in leukotriene E4 was present in LPS-pretreated/D.42 plasma-perfused lungs that was inhibited by WEB 2170. Lastly, significant pulmonary edema was produced when lipid extracts of D.42 plasma or lysophosphatidylcholines were perfused into LPS-pretreated lungs. Lipids caused ALI without vasoconstriction, except at the highest dose employed. In conclusion, both plasma and lipids from stored blood produced pulmonary damage in a model of acute lung injury. TRALI, like the adult respiratory distress syndrome, may be the result of two insults: one derived from stored blood and the other from the clinical condition of the patient. PMID:9525989

  19. 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

  20. 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

  1. 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.

  2. 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.

  3. Direct In Vivo Electrochemical Detection of Haemoglobin in Red Blood Cells

    NASA Astrophysics Data System (ADS)

    Toh, Rou Jun; Peng, Weng Kung; Han, Jongyoon; Pumera, Martin

    2014-08-01

    The electrochemical behavior of iron ion in haemoglobin provides insight to the chemical activity in the red blood cell which is important in the field of hematology. Herein, the detection of haemoglobin in human red blood cells on glassy carbon electrode (GC) was demonstrated. Red blood cells or raw blood cells was immobilized on a glassy carbon electrode surface with Nafion films employed to sandwich the layer of biological sample firmly on the electrode surface. Cyclic voltammetry (CV) analyses revealed a well-defined reduction peak for haemoglobin at about -0.30 V (vs. Ag/AgCl) at the red blood cell (GC-Nf-RBC-3Nf) and blood (GC-Nf-B-3Nf) film modified GCE in a pH 3.5 phosphate buffer solution. We further demonstrated that the complex biological conditions of a human red blood cell displayed no interference with the detection of haemoglobin. Such findings shall have an implication on the possibilities of studying the electrochemical behaviour of haemoglobin directly from human blood, for various scientific and clinical purposes.

  4. 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.

  5. Estrogenic and DNA-damaging activity of Red No. 3 in human breast cancer cells.

    PubMed Central

    Dees, C; Askari, M; Garrett, S; Gehrs, K; Henley, D; Ardies, C M

    1997-01-01

    Exposure to pesticides, dyes, and pollutants that mimic the growth promoting effects of estrogen may cause breast cancer. The pesticide DDT and the food colorant Red No. 3 were found to increase the growth of HTB 133 but not estrogen receptor (ER) negative human breast cells (HTB 125) or rat liver epithelial cells (RLE). Red No. 3, beta-estradiol, and DDT increase ER site-specific DNA binding to the estrogen response element in HTB 133 cells and increase cyclin-dependent kinase 2 activity in MCF-7 breast cancer cells. Site-specific DNA binding by p53 in RLE, HTB 125, HTB 133, and MCF-7 cells was increased when they were treated with Red No. 3, which suggests that cellular DNA was damaged by this colorant. Red No. 3 increased binding of the ER from MCF-7 cells to the estrogen-responsive element. Consumption of Red No. 3, which has estrogenlike growth stimulatory properties and may be genotoxic, could be a significant risk factor in human breast carcinogenesis. Images Figure 4. A Figure 4. B Figure 5. A Figure 5. B Figure 6. Figure 7. A Figure 7. B Figure 7. C PMID:9168006

  6. Direct In Vivo Electrochemical Detection of Haemoglobin in Red Blood Cells

    PubMed Central

    Toh, Rou Jun; Peng, Weng Kung; Han, Jongyoon; Pumera, Martin

    2014-01-01

    The electrochemical behavior of iron ion in haemoglobin provides insight to the chemical activity in the red blood cell which is important in the field of hematology. Herein, the detection of haemoglobin in human red blood cells on glassy carbon electrode (GC) was demonstrated. Red blood cells or raw blood cells was immobilized on a glassy carbon electrode surface with Nafion films employed to sandwich the layer of biological sample firmly on the electrode surface. Cyclic voltammetry (CV) analyses revealed a well-defined reduction peak for haemoglobin at about −0.30 V (vs. Ag/AgCl) at the red blood cell (GC-Nf-RBC-3Nf) and blood (GC-Nf-B-3Nf) film modified GCE in a pH 3.5 phosphate buffer solution. We further demonstrated that the complex biological conditions of a human red blood cell displayed no interference with the detection of haemoglobin. Such findings shall have an implication on the possibilities of studying the electrochemical behaviour of haemoglobin directly from human blood, for various scientific and clinical purposes. PMID:25163492

  7. Red cell parameters in infant and children from the Arabian Peninsula.

    PubMed

    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.

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

    PubMed

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

    2011-04-15

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

  9. 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.

  10. 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.

  11. 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

  12. Production of embryonic and fetal-like red blood cells from human induced pluripotent stem cells.

    PubMed

    Chang, Chan-Jung; Mitra, Koyel; Koya, Mariko; Velho, Michelle; Desprat, Romain; Lenz, Jack; Bouhassira, Eric E

    2011-01-01

    We have previously shown that human embryonic stem cells can be differentiated into embryonic and fetal type of red blood cells that sequentially express three types of hemoglobins recapitulating early human erythropoiesis. We report here that we have produced iPS from three somatic cell types: adult skin fibroblasts as well as embryonic and fetal mesenchymal stem cells. We show that regardless of the age of the donor cells, the iPS produced are fully reprogrammed into a pluripotent state that is undistinguishable from that of hESCs by low and high-throughput expression and detailed analysis of globin expression patterns by HPLC. This suggests that reprogramming with the four original Yamanaka pluripotency factors leads to complete erasure of all functionally important epigenetic marks associated with erythroid differentiation regardless of the age or the tissue type of the donor cells, at least as detected in these assays. The ability to produce large number of erythroid cells with embryonic and fetal-like characteristics is likely to have many translational applications.

  13. 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

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

    PubMed

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

    2015-07-01

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

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

    PubMed Central

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

    2016-01-01

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

  16. 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.

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

    NASA Astrophysics Data System (ADS)

    Jiang, Li-Guo; Wu, Heng-An; Zhou, Xiao-Zhou; Wang, Xiu-Xi

    2010-02-01

    A worm-like chain model based on a spectrin network is employed to study the biomechanics of red blood cells. Coarse-grained molecular dynamics simulations are performed to obtain a stable configuration free of external loadings. We also discuss the influence of two parameters: the average bending modulus and the persistence length. The change in shape of a malaria-infected red blood cell can contribute to the change in its molecular-based structure. As the persistence length of the membrane network in the infected red blood cell decreases, the deformability decreases and the biconcave shape is destroyed. The numerical results are comparable with previously reported experimental results. The coarse-grained model can be used to study the relationship between macro-mechanical properties and molecular-scale structures of cells.

  18. 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.

  19. 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.

  20. 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.

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

    NASA Astrophysics Data System (ADS)

    Zhao, Shihai; Pan, Tsorng-Whay

    2013-11-01

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

  2. Investigation of red blood cell antigens with highly fluorescent and stable semiconductor quantum dots.

    PubMed

    de Farias, Patrícia Maria Albuquerque; Santos, Beate Saegesser; de Menezes, Frederico Duarte; de Carvalho Ferreira, Ricardo; Barjas-Castro, Maria Lourdes; Castro, Vagner; Lima, Paulo Roberto Moura; Fontes, Adriana; Cesar, Carlos Lenz

    2005-01-01

    We report a new methodology for red blood cell antigen expression determination by a simple labeling procedure employing luminescent semiconductor quantum dots. Highly luminescent and stable core shell cadmium sulfide/cadmium hydroxide colloidal particles are obtained, with a predominant size of 9 nm. The core-shell quantum dots are functionalized with glutaraldehyde and conjugated to a monoclonal anti-A antibody to target antigen-A in red blood cell membranes. Erythrocyte samples of blood groups A+, A2+, and O+ are used for this purpose. Confocal microscopy images show that after 30 min of conjugation time, type A+ and A2+ erythrocytes present bright emission, whereas the O+ group cells show no emission. Fluorescence intensity maps show different antigen expressions for the distinct erythrocyte types. The results obtained strongly suggest that this simple labeling procedure may be employed as an efficient tool to investigate quantitatively the distribution and expression of antigens in red blood cell membranes.

  3. [Instant effect of temperature on the oxygen carrying capacity of single living intact red blood cell].

    PubMed

    Yao, Cheng-can; Li, Xiao-kun; Huang, Yao-xiong

    2005-04-01

    The instant effect of temperature on the absorption spectra of the hemoglobin in single living intact red blood cells was investigated, by employing a highly sensitive fast multi-channel micro-spectrophotometer system to perform non-invasive, in situ, real time measurements on the cells. It was found that both the heights and position of the specific peaks in the absorption spectra of intercellular hemoglobin were changed with temperature, indicating that the oxygen carrying capacity of red blood cells varies with temperature. The correlations of the structure and concentration as well as the function of hemoglobin, and the molecular mechanism were also discussed.

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

    PubMed

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

    2001-02-01

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

  5. 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.

  6. Holoprosencephaly and Pure Red Cell Aplasia in a Feline Leukaemia Virus-Positive Kitten.

    PubMed

    Southard, T L; Rodriguez-Ramos Fernandez, J; Priest, H; Stokol, T

    2016-01-01

    A 9-month-old, female, domestic longhair cat with severe anaemia tested positive for feline leukaemia virus (FeLV) and was humanely destroyed and submitted for necropsy examination. Gross findings included a non-divided rostral telencephalon, consistent with semilobar holoprosencephaly. Histological examination of the bone marrow revealed an almost complete absence of erythroid precursor cells, consistent with pure red cell aplasia, and mild to moderate myelofibrosis. This case demonstrates a very unusual central nervous system defect, as well as an atypical presentation of pure red cell aplasia, in a FeLV-positive kitten.

  7. Non-selective voltage-activated cation channel in the human red blood cell membrane.

    PubMed

    Kaestner, L; Bollensdorff, C; Bernhardt, I

    1999-02-04

    Using the patch-clamp technique, a non-selective voltage-activated Na+ and K+ channel in the human red blood cell membrane was found. The channel operates only at positive membrane potentials from about +30 mV (inside positive) onwards. For sodium and potassium ions, similar conductances of about 21 pS were determined. Together with the recently described K+(Na+)/H+ exchanger, this channel is responsible for the increase of residual K+ and Na+ fluxes across the human red blood cell membrane when the cells are suspended in low ionic strength medium.

  8. 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...

  9. 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...

  10. 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...

  11. 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...

  12. 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...

  13. 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...

  14. 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...

  15. 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.

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

    PubMed

    Py, J-Y

    2010-12-01

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

  17. 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.

  18. Role of red cells in preventing the growth of platelet aggregation.

    PubMed

    Machi, J; Sigel, B; Ramos, J R; Justin, J R; Feinberg, H; LeBreton, G C; Robertson, A L

    1984-10-01

    Using high-resolution real-time two-dimensional ultrasound, we have investigated the role of red cells in the growth of already established platelet aggregates under controlled flow conditions. Platelet rich plasma (PRP) was circulated in vitro in horizontally and vertically arranged tubing at mean shear rate ranging from 60 to 0 sec-1, and adenosine diphosphate (ADP) was used to induce platelet aggregation. ADP-induced platelet aggregates grew in size and tended to sediment as shear rate decreased, in particular, below 10 sec-1. At 0 sec-1 (stasis), large clusters of platelet aggregates formed. The addition of washed red cells to produce a hematocrit of only 2% significantly interfered with the growth and sedimentation of platelet aggregates as shear rate was reduced. Formaldehyde-hardened erythrocytes had a similar effect in preventing the growth of platelet aggregates, suggesting that mechanical collision of red cells with platelet aggregates may be the cause of growth inhibition. Therefore, the thrombotic process may be enhanced in red cell poor zones in circulation resulting from flow disturbances associated with vascular stenosis or within artificial organs and extracorporeal systems. The present study also suggested that red cell free PRP should be carefully administered therapeutically.

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

    PubMed Central

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

    2013-01-01

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

  20. Red blood cell plasmalogens and docosahexaenoic acid are independently reduced in primary open-angle glaucoma.

    PubMed

    Acar, Niyazi; Berdeaux, Olivier; Juaneda, Pierre; Grégoire, Stéphane; Cabaret, Stéphanie; Joffre, Corinne; Creuzot-Garcher, Catherine P; Bretillon, Lionel; Bron, Alain M

    2009-12-01

    Among several theories involved in the pathogenesis of primary open-angle glaucoma (POAG), the vascular theory considers the disease to be a consequence of reduced ocular blood flow associated with red blood cell abnormalities. Red blood cell membrane structure and function are influenced by their phospholipid composition. We investigated whether specific lipid entities that may affect the membrane physiology, namely, polyunsaturated fatty acids (PUFAs) and plasmalogens, are modified in POAG and whether these potential variations are related to the stage of glaucoma. Blood samples were collected from 31 POAG patients and 10 healthy individuals. The stage of glaucoma was determined according to the Hodapp and Parrish classification. Lipids were extracted from red blood cell membranes and individual phospholipid species were quantified by liquid chromatography combined with mass spectrometry using triple quadrupole technology. POAG patients had reduced erythrocyte levels of phosphatidyl-choline (PC) carrying docosahexaenoic acid (DHA). POAG patients also displayed lower levels of choline plasmalogens (PlsC) carrying PUFAs other than DHA. These differences were greater as the severity of the disease increased. Linear regressions predicted that red blood cell PlsC levels would decrease years before clinical symptoms, whereas the levels of PC carrying DHA were linearly correlated to visual field loss. Our data demonstrate the selective loss of some individual phospholipid species in red blood cell membranes, which may partly explain their loss of flexibility in POAG.