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Sample records for blood cell exchange

  1. From total blood exchange to erythrocytapheresis and back to treat complications of sickle cell disease.

    Science.gov (United States)

    Ballas, Samir K

    2017-09-01

    Erythrocytapheresis is an important procedure in the management of certain complications of sickle cell disease, including acute stroke, stroke prevention, acute chest syndrome, and multiorgan failure. Erythrocytapheresis in sickle cell disease simply entails the removal of the patient's red blood cells containing the abnormal sickle hemoglobin and replacing them with normal red blood cells carrying normal hemoglobin. In these procedures, the patient's plasma is not exchanged but is returned to the patient. Several studies have demonstrated that the plasma of patients with sickle cell disease contains several components that increase blood viscosity and initiate or promote vaso-occlusion. These factors include increased levels of globulins, especially immunoglobulin G, acute-phase reactants, fibrinogen, coagulation factors, inflammatory mediators, and heme in the steady state and increase further during painful crises. This may explain why, in certain complications of sickle cell disease, such as acute chest syndrome, hepatic crisis, and priapism, erythrocytapheresis by itself may not be effective despite repetitive cycles of red blood cell exchange. The use of therapeutic plasma exchange in addition to erythrocytapheresis in these situations seems to be useful in resolving them more efficiently. The role of therapeutic plasma exchange in the management of certain complications of sickle cell disease needs further evaluation. This commentary addresses the role of therapeutic plasma exchange in the management of complications of sickle cell disease. © 2017 AABB.

  2. Partial Red Blood Cell Exchange in Children and Young Patients with Sickle Cell Disease: Manual Versus Automated Procedure.

    Science.gov (United States)

    Escobar, Carlos; Moniz, Marta; Nunes, Pedro; Abadesso, Clara; Ferreira, Teresa; Barra, António; Lichtner, Anabela; Loureiro, Helena; Dias, Alexandra; Almeida, Helena

    2017-10-31

    The benefits of manual versus automated red blood cell exchange have rarely been documented and studies in young sickle cell disease patients are scarce. We aim to describe and compare our experience in these two procedures. Young patients (≤ 21 years old) who underwent manual- or automated-red blood cell exchange for prevention or treatment of sickle cell disease complications were included. Clinical, technical and hematological data were prospectively recorded and analyzed. Ninety-four red blood cell exchange sessions were performed over a period of 68 months, including 57 manual and 37 automated, 63 for chronic complications prevention, 30 for acute complications and one in the pre-operative setting. Mean decrease in sickle hemoglobin levels was higher in automated-red blood cell exchange (p sickle hemoglobin level decrease per volume removed (p cell exchange and access alarm on automated-red blood cell exchange. No major complication or alloimunization was recorded. Automated-red blood cell exchange decreased sickle hemoglobin levels more efficiently than manual procedure in the setting of acute and chronic complications of sickle cell disease, with minor technical concerns mainly due to vascular access. The threshold of sickle hemoglobin should be individualized for clinical and hematological goals. In our cohort of young patients, the need for an acceptable venous access was a limiting factor, but iron-overload was avoided. Automated red blood cell exchange is safe and well tolerated. It permits a higher sickle hemoglobin removal efficacy, better volume status control and iron-overload avoidance.

  3. Cholesterol Exchange, DNA Damages, Apoptosis and Necrosis of Blood Cells in Severe Concomitant Injury

    Directory of Open Access Journals (Sweden)

    V. V. Moroz

    2008-01-01

    Full Text Available Objective: to study a number of free-radical reactions, the parameters of cholesterol exchange, and the extent of blood cell DNA damages in victims early after concomitant injury. Subjects and methods. The study covered 77 patients who had experienced severe mechanical injury. The patients’ condition on admission was an APACHE II of 19.1±5.4 scores. According to the outcome of the disease, all the patients were divided into 2 groups: 1 deceased patients and 2 survivors. The study was conducted on admission to an intensive care unit and on days 3, 5, 7, and 15. The extent of blood cell DNA damages and the proportion of apoptotic and necrotic blood cells were estimated by gel isolated cell elec-trophoresis (DNA rocket electrophoresis. The «Human 8-oxoGuanine DNA Glycosylate (OGG1 FLARE Assay» kit was used to measure the content of 8-hydroxy-2-deoxyguanosine in cell DNA. The cholesterol and overall antioxida-tive statuses and biochemical parameters were determined on an automatic biochemical Cobas Miras Plus analyzer. Very low-density lipoproteins (VLDL and low-density lipoproteins (LDL were calculated. Results and discussion. In severe concomitant injury, there were increases in DNA damages in the blood cells and in their apoptotic and necrotic processes, which were particularly pronounced on days 3—5. In the group of deceased patients, the increase of 8-hydroxy-2-deoxyguanosine was greater than the normal values on days 5 and 7. On admission, the systemic antioxidative status was greater than the normal values in the survivors and deceased patients and tended to diminish in both groups during an observation. The average statistical values of total cholesterol were lower at all stages of the study. At the stages of the study, the concentration of triglycerides and VLDL were in the normal range in all the patients. At week 1 of the observation, the level of LDL was normal or greater in the survivors than in the deceased. The changes in high

  4. A report of cerebral malaria treated with automated red blood cell exchange.

    Science.gov (United States)

    Anani, Waseem Q; Smith, Gerald P; Irani, Mehraboon; Puca, Kathleen E

    2017-04-01

    Adjunctive automated whole blood or red blood cell exchange (RBCEx) can rapidly decrease malarial hyperparasitemia. Several case reports and series suggest improvement in clinical symptomatology; however, recent Centers of Disease Control and Prevention (CDC) recommendations concluded that RBCEx has no efficacy as an adjunctive therapy. We present a case of mental status changes secondary to cerebral malaria treated with automated RBCEx resulting in rapid and dramatic neurologic improvement. An 84-year-old Somali woman presented with a 3-day history of altered mental status, spiking fevers, chills, bilateral leg pain and weakness, and intermittent diarrhea. Her travel history included a recent trip to Kenya for 1 month without antimalarial chemoprophylaxis. During the hospital stay, her health declined, and she became obtunded. Physical examination revealed fever, tachypnea, hypertension, hypoxia, and no response to verbal or physical stimuli. Her hemoglobin decreased from 12.6 to 6.5 g/dL with 12% intraerythrocytic parasitemia by thin smear. Intraerythrocytic trophozoites and banana-shaped gametocytes were present consistent with Plasmodium falciparum. An emergent 1.5-volume RBC mass automated RBCEx and quinidine infusion decreased her parasitemia to 2%. The patient's mental status improved throughout the procedure, and after the 2½-hour procedure, the patient was alert, oriented, and speaking coherently. The patient continued to receive quinidine and artesunate 1 day later from CDC. Automated RBCEx transfusion reduced the parasite burden and restored neurologic functioning in a patient with cerebral malaria while awaiting definitive treatment with artesunate. © 2017 AABB.

  5. Prophylactic red blood cell exchange may be beneficial in the management of sickle cell disease in pregnancy.

    Science.gov (United States)

    Asma, Suheyl; Kozanoglu, Ilknur; Tarım, Ebru; Sarıturk, Cagla; Gereklioglu, Cigdem; Akdeniz, Aydan; Kasar, Mutlu; Turgut, Nurhilal H; Yeral, Mahmut; Kandemir, Fatih; Boga, Can; Ozdogu, Hakan

    2015-01-01

    Sickle cell disease (SCD) is associated with chronic hemolysis and painful episodes. Pregnancy accelerates sickle cell complications, including prepartum and postpartum vasoocclusive crisis, pulmonary complications, and preeclampsia or eclampsia. Fetal complications include preterm birth and its associated risks, intrauterine growth restriction, and a high rate of perinatal mortality. The purpose of this study was to evaluate pregnancy outcomes in patients with SCD who underwent planned preventive red blood cell exchange (RBCX). We retrospectively evaluated the complications of SCD in 37 pregnant patients. Patients with SCD who had undergone prophylactic RBCX were compared with a control group who had not undergone RBCX during pregnancy. Forty-three exchange procedures were performed in 24 patients. The control group comprised 13 patients with a mean age of 27.4 ± 3.3 years who had not undergone RBCX during pregnancy. Four of the five patients who developed a vasoocclusive crisis died. There was a significant difference in maternal mortality between the study and control groups (p = 0.011). There was also a significant difference in the incidence of vasoocclusive crisis between the study and control groups. One fetal death occurred in the 20th gestational week in a patient in the control group, although there were no postpartum complications in either the babies or the mothers in the control group. This study has demonstrated that prophylactic RBCX during pregnancy is a feasible and safe procedure for prevention of complications. Given the decrease in the risks of transfusion, RBCX warrants further study. © 2014 AABB.

  6. Protein Structure-Function Correlation in Living Human Red Blood Cells Probed by Isotope Exchange-based Mass Spectrometry.

    Science.gov (United States)

    Narayanan, Sreekala; Mitra, Gopa; Muralidharan, Monita; Mathew, Boby; Mandal, Amit K

    2015-12-01

    To gain insight into the underlying mechanisms of various biological events, it is important to study the structure-function correlation of proteins within cells. Structural probes used in spectroscopic tools to investigate protein conformation are similar across all proteins. Therefore, structural studies are restricted to purified proteins in vitro and these findings are extrapolated in cells to correlate their functions in vivo. However, due to cellular complexity, in vivo and in vitro environments are radically different. Here, we show a novel way to monitor the structural transition of human hemoglobin upon oxygen binding in living red blood cells (RBCs), using hydrogen/deuterium exchange-based mass spectrometry (H/DX-MS). Exploiting permeability of D2O across cell membrane, the isotope exchange of polypeptide backbone amide hydrogens of hemoglobin was carried out inside RBCs and monitored using matrix-assisted laser desorption ionization mass spectrometry (MALDI-MS). To explore the conformational transition associated with oxygenation of hemoglobin in vivo, the isotope exchange kinetics was simplified using the method of initial rates. RBC might be considered as an in vivo system of pure hemoglobin. Thus, as a proof-of-concept, the observed results were correlated with structural transition of hemoglobin associated with its function established in vitro. This is the first report on structural changes of a protein upon ligand binding in its endogenous environment. The proposed method might be applicable to proteins in their native state, irrespective of location, concentration, and size. The present in-cell approach opens a new avenue to unravel a plethora of biological processes like ligand binding, folding, and post-translational modification of proteins in living cells.

  7. Exchange transfusion with entirely synthetic red-cell substitute albumin-heme into rats: physiological responses and blood biochemical tests.

    Science.gov (United States)

    Huang, Yubin; Komatsu, Teruyuki; Yamamoto, Hisashi; Horinouchi, Hirohisa; Kobayashi, Koichi; Tsuchida, Eishun

    2004-10-01

    Recombinant human serum albumin (rHSA) incorporating 2-[8-[N-(2-methylimidazolyl)]octanoyloxymethyl]-5,10,15,20-[tetrakis[alpha,alpha,alpha,alpha-o-(1-methylcyclohexanoyl)amino]phenyl]porphinatoiron(II) [albumin-heme (rHSA-heme)] is an artificial hemoprotein which has the capability to transport O(2) in vitro and in vivo. A 20% exchange transfusion with rHSA-heme into anesthetized rats has been performed to evaluate its clinical safety by monitoring the circulation parameters and blood parameters for 6 h after the infusion. Time course changes in all parameters essentially showed the same features as those of the control group (without infusion) and rHSA group (with administration of the same amount of rHSA). Blood biochemical tests of the withdrawn plasma at 6 h after the exchange transfusion have also been carried out. No significant difference was found between the rHSA-heme and rHSA groups, suggesting the initial clinical safety of this entirely synthetic O(2)-carrier as a red-cell substitute.

  8. Phosphate Ion Exchange Resin Used in the Liquid Preservation of Baboon Red Blood Cells.

    Science.gov (United States)

    1982-06-08

    phlebotomy each baboon was sedated with 30 mg of phencyclidine hydrochloride (Sernylan) or with 130 mg of pentobarbital . Using an 18-gauge needle and an AE-2...REFERENCES 1. Valeri CR. Blood banking and the use of frozen blood products. Boca Raton : CRC Press, 1976:35-48. 2. Benesch R, Benesch RE. The effect of

  9. First successful automated red cell exchange (erythrocytapheresis ...

    African Journals Online (AJOL)

    Frequent blood transfusion carries significant complications especially iron overload. Red cell exchange offers a better control both as prophylaxis and therapy for some complications. METHOD: A 32years old male SCD patient had priapism as an indication for Red Cell exchange. A total of 1850ml of his red cells was ...

  10. Efficacy of exchange blood transfusion in the management of ...

    African Journals Online (AJOL)

    Background: Thirteen cases of priapism seen in adult patients with sickle cell disease (SCD) were treated by exchange blood transfusion (EBT) at the University of Maiduguri Teaching Hospital during a five-year period (1996-2000). Each patient was scheduled to receive a total of 12-unit exchange, but due to voluntary ...

  11. Arterio-venous fistula for automated red blood cells exchange in patients with sickle cell disease: Complications and outcomes.

    Science.gov (United States)

    Delville, Marianne; Manceau, Sandra; Ait Abdallah, Nassim; Stolba, Jan; Awad, Sameh; Damy, Thibaud; Gellen, Barnabas; Sabbah, Laurent; Debbache, Karima; Audard, Vincent; Beaumont, Jean-Louis; Arnaud, Cécile; Chantalat-Auger, Christelle; Driss, Françoise; Lefrère, François; Cavazzana, Marina; Franco, Gilbert; Galacteros, Frederic; Ribeil, Jean-Antoine; Gellen-Dautremer, Justine

    2017-02-01

    Erythrocytapheresis (ER) can improve outcome in patients with sickle cell disease (SCD). A good vascular access is required but frequently it can be difficult to obtain for sickle cell patients. Arterio-venous fistulas (AVFs) have been suggested for ER in SCD supported by limited evidence. We report the largest cohort of ER performed with AVFs from three French SCD reference centers. Data of SCD patients undergoing ER with AVFs in the French SCD reference center were retrospectively collected. The inclusion criteria were: SS or Sβ-Thalassemia and AVF surgery for ER. SCD-related complications, transfusion history, details about AVF surgical procedure, echocardiographic data before and after AVF, AVF-related surgical and hemodynamical complications were collected. Twenty-six patients (mean age 20.5 years, mean follow-up 68 months [11-279]) were included. Twenty-three patients (88.5%) required central vascular access before AVF. Fifteen AVFs (58%) were created on the forearm and 11 (42%) on the arm. Nineteen patients (73%) had stenotic, thrombotic or infectious AVF complications. A total of 0.36 stenosis per 1,000 AVF days, 0.37 thrombosis per 1,000 AVF days and 0.078 infections per 1.000 AVF days were observed. The mean AVF lifespan was 51 months [13-218]. One patient with severe pulmonary hypertension worsened after AVF creation and died. We report the first series of SCD patients with AVF for ER, demonstrating that AVFs could be considered as a potential vascular access for ER. Patients with increased risk for hemodynamic intolerance of AVFs must be carefully identified, so that alternative vascular accesses can be considered. Am. J. Hematol. 92:136-140, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  12. Prevalence of exchange blood transfusion in severe ...

    African Journals Online (AJOL)

    Background: Exchange blood transfusion (EBT) is carried out for the treatment of conditions presenting with severe hyperbilirubinaemia and anaemia, such as ABO incompatibility, sepsis, prematurity and birth trauma among others. While it is fast being abandoned as treatment modality for severe neonatal jaundice in the ...

  13. Prevalence of exchange blood transfusion in severe hyper ...

    African Journals Online (AJOL)

    2015-11-09

    Nov 9, 2015 ... ranged from 15mg/dL to 28.5mg/. dL with mean of 21.5 ±13.0mg/dL, while the post EBT SB ... Exchange blood transfusion (EBT) is a procedure done for removal of antibodies coated red blood cells ... cation for EBT whatever the TSB level. In sick new- borns, intervention is required at lower TSB levels men-.

  14. Red blood cell production

    Science.gov (United States)

    ... bone marrow of bones. Stem cells in the red bone marrow called 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 blood ...

  15. In a Canine Pneumonia Model of Exchange-Transfusion, Altering the Age but Not the Volume of Older Red Blood Cells Markedly Alters Outcome

    Science.gov (United States)

    Cortés-Puch, Irene; Remy, Kenneth E.; Solomon, Steven B.; Sun, Junfeng; Wang, Dong; Al-Hamad, Mariam; Kelly, Seth M.; Sinchar, Derek; Bellavia, Landon; Kanias, Tamir; Popovsky, Mark A.; Kim-Shapiro, Daniel B.; Klein, Harvey G.; Natanson, Charles

    2015-01-01

    Background Massive exchange-transfusion of 42-day-old red blood cells (RBCs) in a canine model of S. aureus pneumonia resulted in in vivo hemolysis with increases in cell-free hemoglobin (CFH), transferrin bound iron (TBI), non-transferrin bound iron (NTBI), and mortality. We have previously shown that washing 42-day-old RBCs before transfusion significantly decreased NTBI levels and mortality, but washing 7-day-old RBCs increased mortality and CFH levels. We now report the results of altering volume, washing, and age of RBCs. Study Design and Methods Two-year-old purpose-bred infected beagles were transfused with increasing volumes (5-10, 20-40, or 60-80 mL/kg) of either 42- or 7-day-old RBCs (n=36) or 80 mL/kg of either unwashed or washed RBCs with increasing storage age (14, 21, 28, or 35 days) (n=40). Results All volumes transfused (5-80 mL/kg) of 42-day-old RBCs, resulted in alike (i.e., not significantly different) increases in TBI during transfusion as well as in CFH, lung injury, and mortality rates after transfusion. Transfusion of 80 mL/kg of RBCs stored for 14, 21, 28 and 35 days resulted in increased CFH and NTBI in between levels found at 7 and 42 days of storage. However, washing RBCs of intermediate ages (14-35 days) does not alter NTBI and CFH levels or mortality rates. Conclusions Preclinical data suggest that any volume of 42-day-old blood potentially increases risks during established infection. In contrast, even massive volumes of 7-day-old blood result in minimal CFH and NTBI levels and risks. In contrast to the extremes of storage, washing blood stored for intermediate ages does not alter risks of transfusion or NTBI and CFH clearance. PMID:26469998

  16. Proton exchange membrane fuel cells

    CERN Document Server

    Qi, Zhigang

    2013-01-01

    Preface Proton Exchange Membrane Fuel CellsFuel CellsTypes of Fuel CellsAdvantages of Fuel CellsProton Exchange Membrane Fuel CellsMembraneCatalystCatalyst LayerGas Diffusion MediumMicroporous LayerMembrane Electrode AssemblyPlateSingle CellStackSystemCell Voltage Monitoring Module (CVM)Fuel Supply Module (FSM)Air Supply Module (ASM)Exhaust Management Module (EMM)Heat Management Module (HMM)Water Management Module (WMM)Internal Power Supply Module (IPM)Power Conditioning Module (PCM)Communications Module (COM)Controls Module (CM)SummaryThermodynamics and KineticsTheoretical EfficiencyVoltagePo

  17. Sodium vapor charge exchange cell

    International Nuclear Information System (INIS)

    Hiddleston, H.R.; Fasolo, J.A.; Minette, D.C.; Chrien, R.E.; Frederick, J.A.

    1976-01-01

    An operational sequential charge-exchange ion source yielding a 50 MeV H - current of approximately 8 mA is planned for use with the Argonne 500 MeV booster synchrotron. Progress is reported on the development of a sodium vapor charge-exchange cell as part of that planned effort. Design, fabrication, and operating results to date are presented and discussed

  18. Sodium vapor charge exchange cell

    International Nuclear Information System (INIS)

    Hiddleston, H.R.; Fasolo, J.A.; Minette, D.C.; Chrien, R.E.; Frederick, J.A.

    1976-01-01

    An operational sequential charge-exchange ion source yielding a 50 MeV H - current of approximately 8 mA is planned for use with the Argonne 500 MeV booster synchrotron. We report on the progress for development of a sodium vapor charge-exchange cell as part of that planned effort. Design, fabrication, and operating results to date are presented and discussed. (author)

  19. Red blood cell alloimmunization after blood transfusion

    OpenAIRE

    Schonewille, Henk

    2008-01-01

    Current pretransfusion policy requires the patients’ serum to be tested for the presence of irregular red blood cell antibodies. In case of an antibody, red blood cells lacking the corresponding antigen are transfused after an antiglobulin crossmatch. The aim of the studies in this thesis is primarily to investigate whether this policy should change to improve transfusion safety. This thesis explores the risk on red blood cell alloimmunization after blood transfusion in oncohematologic patien...

  20. Red blood cell alloimmunization after blood transfusion

    NARCIS (Netherlands)

    Schonewille, Henk

    2008-01-01

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

  1. Study of 25 cases of exchange transfusion by reconstituted blood in hemolytic disease of newborn

    Science.gov (United States)

    Sharma, D. C.; Rai, Sunita; Mehra, Aakash; Kaur, M. M.; Sao, Satya; Gaur, Ajay; Sapra, Rahul

    2007-01-01

    This study was aimed to review and establish the practice of exchange transfusion (ET) with reconstituted blood in neonates and to observe fall of bilirubin and its comparison with related studies. Twenty-five neonates diagnosed as hemolytic disease of newborn (HDN) were selected for this study, in which exchange transfusion was carried out as one of the treatments for hyperbilirubinemia. Out of the 25 cases, 15 were of Rhesus (Rh) HDN, while ABO and other blood groups constituted 6 and 4 HDN cases respectively. First, the neonates's and mother's blood samples were subjected to relevant investigations. After that, for neonates having Rh HDN, O Rh negative cells suspended in AB plasma were given, O Rh positive cells suspended in AB plasma were given to ABO HDN; and O positive cells, which were indirect Coomb's cross-matched compatible with neonates’ and mother's serum / plasma, suspended in AB plasma were given to the neonates having HDN because of other blood group antibodies. The exchange transfusion (ET) was carried out taking all aseptic precautions by Push-Pull technique with double-volume exchange transfusion method. The average post-exchange fall in serum indirect bilirubin was (52.01%) in all 25 cases, which was found to be more significant than the previous studies. Looking into the superiority of the exchange transfusion in HDN by reconstituted blood, the reconstituted blood can be modified and supplied as per the requirement and conditions. PMID:21938234

  2. Study of 25 cases of exchange transfusion by reconstituted blood in hemolytic disease of newborn

    Directory of Open Access Journals (Sweden)

    Sharma D

    2007-01-01

    Full Text Available This study was aimed to review and establish the practice of exchange transfusion (ET with reconstituted blood in neonates and to observe fall of bilirubin and its comparison with related studies. Twenty-five neonates diagnosed as hemolytic disease of newborn (HDN were selected for this study, in which exchange transfusion was carried out as one of the treatments for hyperbilirubinemia. Out of the 25 cases, 15 were of Rhesus (Rh HDN, while ABO and other blood groups constituted 6 and 4 HDN cases respectively. First, the neonates′ and mother′s blood samples were subjected to relevant investigations. After that, for neonates having Rh HDN, O Rh negative cells suspended in AB plasma were given, O Rh positive cells suspended in AB plasma were given to ABO HDN; and O positive cells, which were indirect Coomb′s cross-matched compatible with neonates′ and mother′s serum / plasma, suspended in AB plasma were given to the neonates having HDN because of other blood group antibodies. The exchange transfusion (ET was carried out taking all aseptic precautions by Push-Pull technique with double-volume exchange transfusion method. The average post-exchange fall in serum indirect bilirubin was (52.01% in all 25 cases, which was found to be more significant than the previous studies. Looking into the superiority of the exchange transfusion in HDN by reconstituted blood, the reconstituted blood can be modified and supplied as per the requirement and conditions.

  3. Results of exchange transfusions in newborns without blood group incompatibility

    Directory of Open Access Journals (Sweden)

    Servet Yel

    2013-01-01

    Full Text Available Objective: Hyperbilirubinemia is a common problem ofneonatal period that has high morbidity and mortality.Blood exchange is the most effective and urgent treatmentmodality for very high bilirubin levels that can lead toneurotoxicity called as kernicterus. The aim of this studywas to compare 90 minutes exchange transfusion withthat of 120 minutes.Methods: This study was performed at Dicle UniversityMedical Faculty, Neonatal Unit between July 2007 andJune 2008. A total of 36 term newborn (38 - 42 gestationalweek without blood group incompatibility and withtotal serum bilirubin levels over 25 mg/dl were included.Newborns were randomly assigned in two groups eachof them comprise 18 babies as Group 1 underwent 90minute-exchange and Group 2 120 minute. Effectivenessand complications of exchange transfusion were recorded.Newborns with Rh, ABO or subgroup incompatibilities,prematurity or small for gestational age, septicemia,hypothyroidism, G6PD enzyme deficiency, intrauterineinfections, diabetic mother’s baby, hemolytic disease ormetabolic diseases were excluded.Results: There were no significant differences in thebody weight, gestational age, postnatal age, age of mother,total bilirubin and albumin levels, the number of bloodexchange, hospital stay days and complications betweentwo groups (p>0.05. However, mean phototherapy durationwas significantly shorter in 120 minutes transfusiongroup compared with 90 minutes group (p<0.001.Conclusion: Our results indicated that 90 minutes wassufficient for an effective exchange transfusion in severehyperbilirubinemic newborn infants. However longer exchangetransfusion durations may shorten the duration ofphototherapy.Key words: Indirect hyperbilirubinemia, exchange transfusion,newborns, outcome

  4. White Blood Cell Disorders

    Science.gov (United States)

    ... Abbreviations Weights & Measures ENGLISH View Professional English Deutsch Japanese Espaniol Find information on medical topics, symptoms, drugs, ... sample? Analysis of cell surface proteins Chromosomal analysis Cultures for bacteria Determination of the original arrangement of ...

  5. Relaxation and exchange dynamics of hyperpolarized 129Xe in human blood.

    Science.gov (United States)

    Norquay, Graham; Leung, General; Stewart, Neil J; Tozer, Gillian M; Wolber, Jan; Wild, Jim M

    2015-08-01

    (129) Xe-blood NMR was performed over the full blood oxygenation range to evaluate (129) Xe relaxation and exchange dynamics in human blood. Hyperpolarized (129) Xe was equilibrated with blood and isolated plasma, and NMR was performed at 1.5 T. The (129) Xe relaxation rate was found to increase nonlinearly with decreasing blood oxygenation. Three constants were extrapolated: rsO2 =  11.1, a "relaxivity index" characterizing the rate of change of (129) Xe relaxation as a function of blood oxygenation, and 1/T1oHb  =  0.13 s(-1) and 1/T1dHb = 0.42 s(-1) , the (129) Xe relaxation rates in oxygenated blood and deoxygenated blood, respectively. In addition, rate constants, ka =  0.022 ms(-1) and kb =  0.062 ms(-1) , were determined for xenon diffusing between red blood cells (RBCs) and plasma (hematocrit  =  48%). The (129) Xe-O2 relaxivity in plasma, rO2 = 0.075 s(-1) mM(-1) , and the (129) Xe relaxation rate in isolated plasma (without dissolved O2 ), 1/T1,b0 = 0.046 s(-1) , were also calculated. Finally, intrinsic (129) Xe-RBC relaxation rates, 1/T1,aoHb = 0.19 s(-1) and 1/T1,adHb = 0.84 s(-1) , in oxygenated blood and deoxygenated blood, respectively, were calculated. The relaxation and exchange analysis performed in this study should provide a sound experimental basis upon which to design future MR experiments for dissolved xenon transport from the lungs to distal tissues. © 2014 Wiley Periodicals, Inc.

  6. Cigarette smoking increases white blood cell aggregation in whole blood.

    OpenAIRE

    Bridges, A B; Hill, A; Belch, J J

    1993-01-01

    We studied the effect of chronic cigarette smoking on white blood cell aggregation, increased aggregation predisposes to microvascular occlusion and damage. Current smokers had significantly increased white blood cell aggregation when compared with non smokers. The presence of chronically activated white blood cells in current smokers may be relevant in the pathogenesis of ischaemic vascular disease.

  7. Renal intercalated cells and blood pressure regulation

    Directory of Open Access Journals (Sweden)

    Susan M. Wall

    2017-12-01

    Full Text Available Type B and non-A, non-B intercalated cells are found within the connecting tubule and the cortical collecting duct. Of these cell types, type B intercalated cells are known to mediate Cl⁻ absorption and HCO₃⁻ secretion largely through pendrin-dependent Cl⁻/HCO₃⁻ exchange. This exchange is stimulated by angiotensin II administration and is also stimulated in models of metabolic alkalosis, for instance after aldosterone or NaHCO₃ administration. In some rodent models, pendrin-mediated HCO₃⁻ secretion modulates acid-base balance. However, the role of pendrin in blood pressure regulation is likely of more physiological or clinical significance. Pendrin regulates blood pressure not only by mediating aldosterone-sensitive Cl⁻ absorption, but also by modulating the aldosterone response for epithelial Na⁺ channel (ENaC-mediated Na⁺ absorption. Pendrin regulates ENaC through changes in open channel of probability, channel surface density, and channels subunit total protein abundance. Thus, aldosterone stimulates ENaC activity through both direct and indirect effects, the latter occurring through its stimulation of pendrin expression and function. Therefore, pendrin contributes to the aldosterone pressor response. Pendrin may also modulate blood pressure in part through its action in the adrenal medulla, where it modulates the release of catecholamines, or through an indirect effect on vascular contractile force. This review describes how aldosterone and angiotensin II-induced signaling regulate pendrin and the contributory role of pendrin in distal nephron function and blood pressure.

  8. Specific features of red blood cell morphology in hemolytic disease neonates undergoing intrauterine intravascular blood transfusion

    Directory of Open Access Journals (Sweden)

    A. V. Ivanova

    2016-01-01

    Full Text Available The paper presents data on the characteristics of red blood cell morphology in infants who have undergone intrauterine intravascular blood transfusion for hemolytic disease of the fetus. The infants are shown to have a reduction in the mean volume of red blood cells and in their mean level of hemoglobin, a decrease in the fraction of fetal hemoglobin and an increase in oxygen tension at half saturation. The above morphological characteristics of red blood cells remain decreased during the neonatal period after exchange transfusion or others, as clinically indicated, which seems to suggest that the compensatory-adaptive mechanisms to regulate hematopoiesis are exhausted and a donor’s red blood cells continue to be predominant.

  9. Proton exchange membrane fuel cells modeling

    CERN Document Server

    Gao, Fengge; Miraoui, Abdellatif

    2013-01-01

    The fuel cell is a potential candidate for energy storage and conversion in our future energy mix. It is able to directly convert the chemical energy stored in fuel (e.g. hydrogen) into electricity, without undergoing different intermediary conversion steps. In the field of mobile and stationary applications, it is considered to be one of the future energy solutions.Among the different fuel cell types, the proton exchange membrane (PEM) fuel cell has shown great potential in mobile applications, due to its low operating temperature, solid-state electrolyte and compactness.This book pre

  10. Red blood cells in thrombosis.

    Science.gov (United States)

    Byrnes, James R; Wolberg, Alisa S

    2017-10-19

    Red blood cells (RBCs) have historically been considered passive bystanders in thrombosis. However, clinical and epidemiological studies have associated quantitative and qualitative abnormalities in RBCs, including altered hematocrit, sickle cell disease, thalassemia, hemolytic anemias, and malaria, with both arterial and venous thrombosis. A growing body of mechanistic studies suggests that RBCs can promote thrombus formation and enhance thrombus stability. These findings suggest that RBCs may contribute to thrombosis pathophysiology and reveal potential strategies for therapeutically targeting RBCs to reduce thrombosis. © 2017 by The American Society of Hematology.

  11. Avoiding Anemia: Boost Your Red Blood Cells

    Science.gov (United States)

    ... Issues Subscribe January 2014 Print this issue Avoiding Anemia Boost Your Red Blood Cells En español Send ... Disease When Blood Cells Bend Wise Choices Preventing Anemia To prevent or treat iron-deficiency anemia: Eat ...

  12. A case of ABO-incompatible blood transfusion treated by plasma exchange therapy and continuous hemodiafiltration.

    Science.gov (United States)

    Namikawa, Akio; Shibuya, Yuko; Ouchi, Haruki; Takahashi, Hiroko; Furuto, Yoshitaka

    2018-05-01

    ABO-incompatible blood transfusion is potentially a life-threatening event. A 74-year-old type O Rh-positive male was accidentally transfused with 280 mL type B Rh-positive red blood cells during open right hemicolectomy, causing ABO-incompatible blood transfusion. Immediately after the transfusion, the patient experienced a hypotension episode followed by acute hemolytic reaction, disseminated intravascular coagulation and acute kidney injury. Plasma exchange therapy was performed to remove anti-B antibody and free hemoglobin because they caused acute hemolytic reaction, disseminated intravascular coagulation, and acute kidney injury. Free hemoglobin levels decreased from 13 to 2 mg/dL for 2 h. Continuous hemodiafiltration was used to stabilize hemodynamics. The patient was successfully treated for acute hemolytic reaction, disseminated intravascular coagulation, and acute kidney injury. Plasma exchange therapy and continuous hemodiafiltration are likely to be effective treatments for ABO-incompatible blood transfusion, and further studies are required to assess this effectiveness in future.

  13. Red Blood Cell.pm6

    African Journals Online (AJOL)

    Adele

    ABSTRACT. Introduction: The practice of warming blood for transfusion by immersion into a waterbath has been investigated. Objective: To find the maximum waterbath temperature at which blood can be heated effectively without effecting the red blood cell functional and structural integrity. Method: Blood, three days after ...

  14. 21 CFR 640.10 - Red Blood Cells.

    Science.gov (United States)

    2010-04-01

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

  15. The effect of storage time of human red cells on intestinal microcirculatory oxygenation in a rat isovolemic exchange model

    NARCIS (Netherlands)

    Raat, N. J.; Verhoeven, A. J.; Mik, E. G.; Gouwerok, C. W.; Verhaar, R.; Goedhart, P. T.; de Korte, D.; Ince, C.

    2005-01-01

    Objective: To determine whether the storage time of human leukodepleted red blood cell concentrates compromises intestinal microvascular oxygen concentration oxygen (muPo(2)) during isovolemic exchange transfusion at low hematocrit. Design: Prospective, randomized, controlled study. Setting:

  16. Red Blood Cell Storage Lesion

    Directory of Open Access Journals (Sweden)

    Daryl J. Kor

    2009-10-01

    Full Text Available The past two decades have witnessed increased scrutiny regarding efficacy and risk of the once unquestioned therapy of red blood cell (RBC transfusion. Simultaneously, a variety of changes have been identified within the RBC and storage media during RBC preservation that are correlated with reduced tissue oxygenation and transfusion-associated adverse effects. These alterations are collectively termed the storage lesion and include extensive biochemical, biomechanical, and immunologic changes involving cells of diverse origin. Time-dependent falls is 2,3-diphosphoglycerate, intracellular RBC adenosine triphosphate, and nitric oxide have been shown to impact RBC deformability and delivery of oxygen to the end-organ. The accumulation of biologic response modifiers such as soluble CD40 ligand (sCD40L, lysophosphatidylcholine (lyso-PC, and Regulated on Activation, Normal T-cell Expressed and Secreted (RANTES have been associated with altered recipient immune function as well. This review will address the alterations occurring within the RBC and storage media during RBC preservation and will address the potential clinical consequence thereof.

  17. Effect of borax on immune cell proliferation and sister chromatid exchange in human chromosomes

    OpenAIRE

    Pongsavee Malinee

    2009-01-01

    Abstract Background Borax is used as a food additive. It becomes toxic when accumulated in the body. It causes vomiting, fatigue and renal failure. Methods The heparinized blood samples from 40 healthy men were studied for the impact of borax toxicity on immune cell proliferation (lymphocyte proliferation) and sister chromatid exchange in human chromosomes. The MTT assay and Sister Chromatid Exchange (SCE) technic were used in this experiment with the borax concentrations of 0.1, 0.15, 0.2, 0...

  18. When Blood Cells Bend: Understanding Sickle Cell Disease

    Science.gov (United States)

    ... Subscribe April 2012 Print this issue When Blood Cells Bend Understanding Sickle Cell Disease Send us your ... Diabetes? Sound Health Wise Choices Living with Sickle Cell Disease See a sickle cell disease expert regularly. ...

  19. Red Blood Cell Susceptibility to Pneumolysin

    Science.gov (United States)

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

    2016-01-01

    This study investigated the effect of the biochemical and biophysical properties of the plasma membrane as well as membrane morphology on the susceptibility of human red blood cells to the cholesterol-dependent cytolysin pneumolysin, a key virulence factor of Streptococcus pneumoniae, using single cell studies. We show a correlation between the physical properties of the membrane (bending rigidity and surface and dipole electrostatic potentials) and the susceptibility of red blood cells to pneumolysin-induced hemolysis. We demonstrate that biochemical modifications of the membrane induced by oxidative stress, lipid scrambling, and artificial cell aging modulate the cell response to the toxin. We provide evidence that the diversity of response to pneumolysin in diabetic red blood cells correlates with levels of glycated hemoglobin and that the mechanical properties of the red blood cell plasma membrane are altered in diabetes. Finally, we show that diabetic red blood cells are more resistant to pneumolysin and the related toxin perfringolysin O relative to healthy red blood cells. Taken together, these studies indicate that the diversity of cell response to pneumolysin within a population of human red blood cells is influenced by the biophysical and biochemical status of the plasma membrane and the chemical and/or oxidative stress pre-history of the cell. PMID:26984406

  20. Immune Cells in Blood Recognize Tumors

    Science.gov (United States)

    NCI scientists have developed a novel strategy for identifying immune cells circulating in the blood that recognize specific proteins on tumor cells, a finding they believe may have potential implications for immune-based therapies.

  1. Review of cell performance in anion exchange membrane fuel cells

    Science.gov (United States)

    Dekel, Dario R.

    2018-01-01

    Anion exchange membrane fuel cells (AEMFCs) have recently received increasing attention since in principle they allow for the use of non-precious metal catalysts, which dramatically reduces the cost per kilowatt of power in fuel cell devices. Until not long ago, the main barrier in the development of AEMFCs was the availability of highly conductive anion exchange membranes (AEMs); however, improvements on this front in the past decade show that newly developed AEMs have already reached high levels of conductivity, leading to satisfactory cell performance. In recent years, a growing number of research studies have reported AEMFC performance results. In the last three years, new records in performance were achieved. Most of the literature reporting cell performance is based on hydrogen-AEMFCs, although an increasing number of studies have also reported the use of fuels others than hydrogen - such as alcohols, non-alcohol C-based fuels, as well as N-based fuels. This article reviews the cell performance and performance stability achieved in AEMFCs through the years since the first reports in the early 2000s.

  2. ORIGINAL ARTICLE Sister chromatid exchange in peripheral blood ...

    African Journals Online (AJOL)

    salah

    mutations and more recently, CGH and multicolor fluorescence in situ hybrid- ization (M-FISH) have been applied to identify many gains and losses of DNA sequences and loci in breast tumors.1. The phenomenon of sister chromatid exchange (SCE) is a symmetrical ex- change of apparently identical portions.

  3. Sister chromatid exchange in peripheral blood lymphocytes as a ...

    African Journals Online (AJOL)

    Introduction: Sister chromatid exchanges (SCEs) can be induced by various genotoxic treatments, suggesting that SCEs refl ect a DNA repair process and it may be a good index for assessment of genomic instability. However, the occurrence of genetic instability and in particular, of spontaneous SCEs has been strongly ...

  4. Trapping cells in paper for white blood cell count.

    Science.gov (United States)

    Zhang, Yi; Bai, Jianhao; Wu, Hong; Ying, Jackie Y

    2015-07-15

    White blood cell count is an important indicator of each individual's health condition. An abnormal white blood cell count usually results from an infection, cancer, or other conditions that trigger systemic inflammation responses. White blood cell count also provides predictive information on the incidence of cardiovascular diseases and Type 2 diabetes. Therefore, monitoring white blood cell count on a regular basis can potentially help individuals to take preventive measures and improve healthcare outcomes. Currently, white blood cell count is primarily conducted in centralized laboratories, and it requires specialized equipment and dedicated personnel to perform the test and interpret the results. So far there has been no rapid test that allows white blood cell count in low-resource settings. In this study, we have demonstrated a vertical flow platform that quantifies white blood cells by trapping them in the paper. White blood cells were tagged with gold nanoparticles, and flowed through the paper via a small orifice. The white blood cell count was determined by measuring the colorimetric intensity of gold nanoparticles on the surface of white blood cells that were trapped in the paper mesh. Using this platform, we were able to quantify white blood cells in 15 μL of blood, and visually differentiate the abnormal count of white blood cells from the normal count. The proposed platform enabled rapid white blood cell count in low resource settings with a small sample volume requirement. Its low-cost, instrument-free operations would be attractive for point-of-care applications. Copyright © 2015 Elsevier B.V. All rights reserved.

  5. Dialyzer-augmented whole blood and plasma exchange for patients with hepatic or hepatorenal failure.

    Science.gov (United States)

    Buselmeier, T J; Merino, G E; Rodrigo, F; Meyer, R M; Bosl, B H; Kjellstrand, C M; Simmons, R L; Najarian, J S

    1975-01-01

    We have utilized new methods of dialyzer-augmented whole blood and plasma exchange tranfusion in the treatment of hepatic coma. The method employs the new fast flow Buselmeier shunt so that the exchange can be done from a peripheral radial artery shunt site rather than a shunt site in a more major vessel, such as the brachial artery. The method employs in-line dialysis of citrated (CPD) blood or plasma to normalize pH, electrolytes, and blood sugar while infusion heparinization decreases heparin requirements. The application of a single roller pump to the administration and withdrawal lines (placed in opposite directions) helps equalize inflow and outflow where whole blood exchange is done while identical opposing pumps accomplish the same with plasma exchange. The administration of albumin and metaraminol bitartate prevents hypotension due to fluid shifts or compartmental venous dilatation. A closed circuit which does not require disconnection throughout the 30- 60-minute whole blood exchange or the 2 1/2-hour plasma exchange decreases the risk of septic contamination to both medical staff and patients.

  6. Contradictions of value: between use and exchange in cord blood bioeconomy.

    Science.gov (United States)

    Brown, Nik

    2013-01-01

    Umbilical cord blood (CB) has become established as an increasingly viable clinical alternative to bone marrow in the treatment of leukaemia leading to the construction of a global network of CB banks promoted through a moral ethos of gift. Additionally, some banks offer the opportunity to retain stem cells privately. CB is discursively presented as clinical 'waste', a 'by-product' of birthing. In this way CB units are made available to a global exchange-based bioeconomy. Crucially, CB collection has developed in parallel with several necessary obstetric practices, especially the immediate clamping of the cord following delivery, essential to high volume collection. However, this article strongly suggests the promotional basis of CB banking (such as by gift, waste or donation) is in tension with the growing preference of new parents to delay cord clamping. Based on focus groups with expectant parents, the promotion of CB banking can in fact be seen to feed into critical reflection on the value of CB for newborn infants, potentially reinvigorating a tradition of delayed umbilical cord clamping. Theoretically, these contradictory systems of valuing are conceptualised through recent literature on bioeconomy and Marx's writings on the contrasting tensions between use and exchange value. © 2012 The Author. Sociology of Health & Illness © 2012 Foundation for the Sociology of Health & Illness/Blackwell Publishing Ltd.

  7. Heat exchanger for fuel cell power plant reformer

    Science.gov (United States)

    Misage, Robert; Scheffler, Glenn W.; Setzer, Herbert J.; Margiott, Paul R.; Parenti, Jr., Edmund K.

    1988-01-01

    A heat exchanger uses the heat from processed fuel gas from a reformer for a fuel cell to superheat steam, to preheat raw fuel prior to entering the reformer and to heat a water-steam coolant mixture from the fuel cells. The processed fuel gas temperature is thus lowered to a level useful in the fuel cell reaction. The four temperature adjustments are accomplished in a single heat exchanger with only three heat transfer cores. The heat exchanger is preheated by circulating coolant and purge steam from the power section during startup of the latter.

  8. Calcium exchange, structure, and function in cultured adult myocardial cells

    International Nuclear Information System (INIS)

    Langer, G.A.; Frank, J.S.; Rich, T.L.; Orner, F.B.

    1987-01-01

    Cells digested from adult rat heart and cultured for 14 days demonstrate all the structural elements, in mature form, associated with the process of excitation-contraction (EC) coupling. The transverse tubular (TT) system is well developed with an extensive junctional sarcoplasmic reticulum (JSR). In nonphosphate-containing buffer contraction of the cells is lost as rapidly as zero extracellular Ca concentration ([Ca] 0 ) solution is applied and a negative contraction staircase is produced on increase of stimulation frequency. Structurally and functionally the cells have the characteristics of adult cells in situ. 45 Ca exchange and total 45 Ca measurement in N-2-hydroxyethylpiperazine N'-2-ethanesulfonic acid (HEPES)-buffered perfusate define three components of cellular Ca: 1) a rapidly exchangeable component accounting for 36% of total Ca, 2) a slowly exchangeable component (t/sub 1/2/ 53 min) accounting for 7% total Ca, and 3) the remaining 57% cellular Ca is inexchangeable (demonstrates no significant exchange within 60 min). The slowly exchangeable component can be increased 10-fold within 60 min by addition of phosphate to the perfusate. The Ca distribution and exchange characteristics are little different from those of 3-day cultures of neonatal rat heart previously studied. The results suggest that the cells are representative of adult cells in situ and that both sarcolemmal-bound and sarcoplasmic reticular Ca contribute to the component of Ca that is rapidly exchangeable

  9. Allogeneic Peripheral Blood Stem Cell Harvest

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. Allogeneic Peripheral Blood Stem Cell Harvest. Mobilization protocol. G-CSF 10 mcg/Kg / day for 5 days. Pheresis. Cobe Spectra; Haemonetics mcs+. Enumeration. CD34 counts; Cfu-GM assays.

  10. White Blood Cell Counts and Malaria

    National Research Council Canada - National Science Library

    McKenzie, F. E; Prudhomme, Wendy A; Magill, Alan J; Forney, J. R; Permpanich, Barnyen; Lucas, Carmen; Gasser, Jr., Robert A; Wongsrichanalai, Chansuda

    2005-01-01

    White blood cells (WBCs) were counted in 4697 individuals who presented to outpatient malaria clinics in Maesod, Tak Province, Thailand, and Iquitos, Peru, between 28 May and 28 August 1998 and between 17 May and 9 July 1999...

  11. Stimulated-healing of proton exchange membrane fuel cell catalyst

    NARCIS (Netherlands)

    Latsuzbaia, R.; Negro, E.; Koper, G.J.M.

    2013-01-01

    Platinum nanoparticles, which are used as catalysts in Proton Exchange Membrane Fuel Cells (PEMFC), tend to degrade after long-term operation. We discriminate the following mechanisms of the degradation: poisoning, migration and coalescence, dissolution, and electrochemical Ostwald ripening. There

  12. Proton Exchange Membrane Fuel Cells Applied for Transport Sector

    DEFF Research Database (Denmark)

    Hosseinzadeh, Elham; Rokni, Masoud

    2010-01-01

    A thermodynamic analysis of a PEMFC (proton exchange membrane fuel cell) is investigated. PEMFC may be the most promising technology for fuel cell automotive systems, which is operating at quite low temperatures, (between 60 to 80℃). In this study the fuel cell motive power part of a lift truck has...

  13. Radionuclide blood cell survival studies

    International Nuclear Information System (INIS)

    Bentley, S.A.; Miller, D.T.

    1986-01-01

    Platelet and red cell survival studies are reviewed. The use of 51 Cr and di-isopropylfluoridate labelled with tritium or 32 P is discussed for red cell survival study and 51 Cr and 111 In-oxine are considered as platelet labels. (UK)

  14. The origin of blood stem cells

    NARCIS (Netherlands)

    J.C. Boisset

    2012-01-01

    textabstractThe development of cell biology research coincides with the advance of microscopes in the 19th century. It was finally possible to directly observe the various blood cell types and to witness their proliferation and differentiation (Mazzarello, 1999). On the basis of his observations,

  15. Haemopoietic progenitor cells in human peripheral blood

    International Nuclear Information System (INIS)

    Zwaan, F.E.

    1980-01-01

    The purpose of the investigation reported is to purify haemopoietic progenitor cells from human peripheral blood using density gradient centrifugation in order to isolate a progenitor cell fraction without immunocompetent cells. The purification technique of peripheral blood flow colony forming unit culture (CFU-c) by means of density gradient centrifugation and a combined depletion of various rosettes is described. The results of several 'in vitro' characteristics of purified CFU-c suspensions and of the plasma clot diffusion chamber culture technique are presented. Irradiation studies revealed that for both human bone marrow and peripheral blood the CFU-c were less radioresistant than clusters. Elimination of monocytes (and granulocytes) from the test suspensions induced an alteration in radiosensitivity pararmeters. The results obtained with the different techniques are described by analysing peripheral progenitor cell activity in myeloproliferative disorders. (Auth.)

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

    DEFF Research Database (Denmark)

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

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

  17. Blood cells radiolabelling achievements, challanges, and prospects

    International Nuclear Information System (INIS)

    Weininger, Jolie; Trumper, Jacob

    1987-01-01

    A study in performed about the different ways of blood cells radiolabelling. The labelling of red blood cells (RBCs), compared with that of other blood cells, is facilitated by several factors such as a) RBCs are the most abundant of all cellular blood elements, b) they are relatively easy to separate and manipulate in vitro, c) in vitro they are less dependent on energy and nutricional requirements, d) they are easy to label due to the presence of a variety of cellular transport mechanism. 99m Tc was reconized and became as the ideal radioisotope for nuclear medicine imaging. After considerations about RBCs radiolabelling, it is presented a new in vitro technique based on the BNL kit, developed by Srivastava and co-workers. The Sorep optimized one-vial labelling method for 2 ml whole blood. In vivo and in vivo/in vitro labelling are presented too, the last method seems to combine the superior binding efficiency of in vitro labelling with the convenience of in vitro labelling. Lipophilic chelates of 111 In with oxine, acetylacetone, tropolone and mercaptopyridine N-oxide have been used successfully for labelling platelets and leukocytes. A very promising aproach is the labelling of cells with monoclonal antibodies and the developing optimized methods for in vitro labelling with various radionuclides such as 123 I, 125 I, 131 I, 111 I and 99m Tc. The advantages of the antibody technique over conventional cell labelling are shown. (M.E.L.) [es

  18. Recent developments in blood cell labeling research

    International Nuclear Information System (INIS)

    Srivastava, S.C.; Straub, R.F.; Meinken, G.E.

    1988-01-01

    A number of recent developments in research on blood cell labeling techniques are presented. The discussion relates to three specific areas: (1) a new in vitro method for red blood cell labeling with /sup 99m/Tc; (2) a method for labeling leukocytes and platelets with /sup 99m/Tc; and (3) the use of monoclonal antibody technique for platelet labeling. The advantages and the pitfalls of these techniques are examined in the light of available mechanistic information. Problems that remain to be resolved are reviewed. An assessment is made of the progress as well as prospects in blood cell labeling methodology including that using the monoclonal antibody approach. 37 refs., 4 figs

  19. Recent developments in blood cell labeling research

    Energy Technology Data Exchange (ETDEWEB)

    Srivastava, S.C.; Straub, R.F.; Meinken, G.E.

    1988-09-07

    A number of recent developments in research on blood cell labeling techniques are presented. The discussion relates to three specific areas: (1) a new in vitro method for red blood cell labeling with /sup 99m/Tc; (2) a method for labeling leukocytes and platelets with /sup 99m/Tc; and (3) the use of monoclonal antibody technique for platelet labeling. The advantages and the pitfalls of these techniques are examined in the light of available mechanistic information. Problems that remain to be resolved are reviewed. An assessment is made of the progress as well as prospects in blood cell labeling methodology including that using the monoclonal antibody approach. 37 refs., 4 figs.

  20. Countercurrent heat exchange and thermoregulation during blood-feeding in kissing bugs.

    Science.gov (United States)

    Lahondère, Chloé; Insausti, Teresita C; Paim, Rafaela Mm; Luan, Xiaojie; Belev, George; Pereira, Marcos H; Ianowski, Juan P; Lazzari, Claudio R

    2017-11-21

    Blood-sucking insects experience thermal stress at each feeding event on endothermic vertebrates. We used thermography to examine how kissing-bugs Rhodnius prolixus actively protect themselves from overheating. During feeding, these bugs sequester and dissipate the excess heat in their heads while maintaining an abdominal temperature close to ambient. We employed a functional-morphological approach, combining histology, µCT and X-ray-synchrotron imaging to shed light on the way these insects manage the flow of heat across their bodies. The close alignment of the circulatory and ingestion systems, as well as other morphological characteristics, support the existence of a countercurrent heat exchanger in the head of R. prolixus , which decreases the temperature of the ingested blood before it reaches the abdomen. This kind of system has never been described before in the head of an insect. For the first time, we show that countercurrent heat exchange is associated to thermoregulation during blood-feeding.

  1. Countercurrent heat exchange and thermoregulation during blood-feeding in kissing bugs

    Science.gov (United States)

    Lahondère, Chloé; Insausti, Teresita C; Belev, George; Pereira, Marcos H

    2017-01-01

    Blood-sucking insects experience thermal stress at each feeding event on endothermic vertebrates. We used thermography to examine how kissing-bugs Rhodnius prolixus actively protect themselves from overheating. During feeding, these bugs sequester and dissipate the excess heat in their heads while maintaining an abdominal temperature close to ambient. We employed a functional-morphological approach, combining histology, µCT and X-ray-synchrotron imaging to shed light on the way these insects manage the flow of heat across their bodies. The close alignment of the circulatory and ingestion systems, as well as other morphological characteristics, support the existence of a countercurrent heat exchanger in the head of R. prolixus, which decreases the temperature of the ingested blood before it reaches the abdomen. This kind of system has never been described before in the head of an insect. For the first time, we show that countercurrent heat exchange is associated to thermoregulation during blood-feeding. PMID:29157359

  2. Vascular Patterns in Iguanas and Other Squamates: Blood Vessels and Sites of Thermal Exchange.

    Directory of Open Access Journals (Sweden)

    William Ruger Porter

    Full Text Available Squamates use the circulatory system to regulate body and head temperatures during both heating and cooling. The flexibility of this system, which possibly exceeds that of endotherms, offers a number of physiological mechanisms to gain or retain heat (e.g., increase peripheral blood flow and heart rate, cooling the head to prolong basking time for the body as well as to shed heat (modulate peripheral blood flow, expose sites of thermal exchange. Squamates also have the ability to establish and maintain the same head-to-body temperature differential that birds, crocodilians, and mammals demonstrate, but without a discrete rete or other vascular physiological device. Squamates offer important anatomical and phylogenetic evidence for the inference of the blood vessels of dinosaurs and other extinct archosaurs in that they shed light on the basal diapsid condition. Given this basal positioning, squamates likewise inform and constrain the range of physiological thermoregulatory mechanisms that may have been found in Dinosauria. Unfortunately, the literature on squamate vascular anatomy is limited. Cephalic vascular anatomy of green iguanas (Iguana iguana was investigated using a differential-contrast, dual-vascular injection (DCDVI technique and high-resolution X-ray microcomputed tomography (μCT. Blood vessels were digitally segmented to create a surface representation of vascular pathways. Known sites of thermal exchange, consisting of the oral, nasal, and orbital regions, were given special attention due to their role in brain and cephalic thermoregulation. Blood vessels to and from sites of thermal exchange were investigated to detect conserved vascular patterns and to assess their ability to deliver cooled blood to the dural venous sinuses. Arteries within sites of thermal exchange were found to deliver blood directly and through collateral pathways. The venous drainage was found to have multiple pathways that could influence neurosensory

  3. Vascular Patterns in Iguanas and Other Squamates: Blood Vessels and Sites of Thermal Exchange.

    Science.gov (United States)

    Porter, William Ruger; Witmer, Lawrence M

    2015-01-01

    Squamates use the circulatory system to regulate body and head temperatures during both heating and cooling. The flexibility of this system, which possibly exceeds that of endotherms, offers a number of physiological mechanisms to gain or retain heat (e.g., increase peripheral blood flow and heart rate, cooling the head to prolong basking time for the body) as well as to shed heat (modulate peripheral blood flow, expose sites of thermal exchange). Squamates also have the ability to establish and maintain the same head-to-body temperature differential that birds, crocodilians, and mammals demonstrate, but without a discrete rete or other vascular physiological device. Squamates offer important anatomical and phylogenetic evidence for the inference of the blood vessels of dinosaurs and other extinct archosaurs in that they shed light on the basal diapsid condition. Given this basal positioning, squamates likewise inform and constrain the range of physiological thermoregulatory mechanisms that may have been found in Dinosauria. Unfortunately, the literature on squamate vascular anatomy is limited. Cephalic vascular anatomy of green iguanas (Iguana iguana) was investigated using a differential-contrast, dual-vascular injection (DCDVI) technique and high-resolution X-ray microcomputed tomography (μCT). Blood vessels were digitally segmented to create a surface representation of vascular pathways. Known sites of thermal exchange, consisting of the oral, nasal, and orbital regions, were given special attention due to their role in brain and cephalic thermoregulation. Blood vessels to and from sites of thermal exchange were investigated to detect conserved vascular patterns and to assess their ability to deliver cooled blood to the dural venous sinuses. Arteries within sites of thermal exchange were found to deliver blood directly and through collateral pathways. The venous drainage was found to have multiple pathways that could influence neurosensory tissue temperature

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

    Science.gov (United States)

    van Rossen, M E; Stoop, M P; Hofland, L J; van Koetsveld, P M; Bonthuis, F; Jeekel, J; Marquet, R L; van Eijck, C H

    1999-04-01

    Perioperative blood transfusion has been associated with increased tumour recurrence and poor prognosis in colorectal cancer. Blood loss in the peritoneal cavity might be a tumour-promoting factor for local recurrence. The aim of this study was to investigate whether blood in the peritoneal cavity affects local tumour recurrence. In an established in vivo rat model the effect of 1.5 ml syngeneic whole blood on tumour cell adhesion and tumour growth was investigated. In the same model the effect of 1.5 ml pure red blood cell (RBC) concentrate and 1.5 ml RBC-derived substances on tumour cell adhesion was studied. In an established in vitro model the effect of increasing numbers of RBCs (0-250 bx 10(6)) on tumour cell adhesion and tumour growth was assessed. Both the presence of blood and RBC concentrate in the peritoneal cavity prevented tumour cell adhesion in vivo (overall P effect on tumour cell adhesion. In in vitro studies RBCs inhibited tumour cell adhesion but not tumour growth. RBC-derived factors prevent tumour cell adhesion to the peritoneum, and consequently tumour recurrence.

  5. Golgi-associated anion exchanger, AE2:identification, cell type specific targeting and structural role in the Golgi complex

    OpenAIRE

    Holappa, K. (Katja)

    2004-01-01

    Abstract Anion exchanger 2 (AE2) is a member of the anion exchanger gene family, which includes three additional members, AE1, AE3, and AE4. They are also known as Na+-independent Cl-/HCO3- exchangers, and their major function is to regulate intracellular pH and chloride concentration. All four isoforms have several N-terminally truncated variants that are often expressed cell type specifically. Red blood cells express the full-length AE1 isoform that interacts with ankyrin, an adapter pro...

  6. Red blood cell alloimmunization in sickle cell disease patients in ...

    African Journals Online (AJOL)

    Objective: Alloimmunization is a recognized complication of red blood cell (RBC) transfusion and causes delayed hemolytic transfusion reactions and provides problems sourcing compatible blood for future transfusions. The objective of this study was to determine the frequency of RBC alloimmunization in SCD patients in ...

  7. Sorting white blood cells in microfabricated arrays

    Science.gov (United States)

    Castelino, Judith Andrea Rose

    Fractionating white cells in microfabricated arrays presents the potential for detecting cells with abnormal adhesive or deformation properties. A possible application is separating nucleated fetal red blood cells from maternal blood. Since fetal cells are nucleated, it is possible to extract genetic information about the fetus from them. Separating fetal cells from maternal blood would provide a low cost noninvasive prenatal diagnosis for genetic defects, which is not currently available. We present results showing that fetal cells penetrate further into our microfabricated arrays than adult cells, and that it is possible to enrich the fetal cell fraction using the arrays. We discuss modifications to the array which would result in further enrichment. Fetal cells are less adhesive and more deformable than adult white cells. To determine which properties limit penetration, we compared the penetration of granulocytes and lymphocytes in arrays with different etch depths, constriction size, constriction frequency, and with different amounts of metabolic activity. The penetration of lymphocytes and granulocytes into constrained and unconstrained arrays differed qualitatively. In constrained arrays, the cells were activated by repeated shearing, and the number of cells stuck as a function of distance fell superexponentially. In unconstrained arrays the number of cells stuck fell slower than an exponential. We attribute this result to different subpopulations of cells with different sticking parameters. We determined that penetration in unconstrained arrays was limited by metabolic processes, and that when metabolic activity was reduced penetration was limited by deformability. Fetal cells also contain a different form of hemoglobin with a higher oxygen affinity than adult hemoglobin. Deoxygenated cells are paramagnetic and are attracted to high magnetic field gradients. We describe a device which can separate cells using 10 μm magnetic wires to deflect the paramagnetic

  8. Photomodification of human immunocompetent blood cells

    Energy Technology Data Exchange (ETDEWEB)

    Krylenkov, V.A.; Ogurtsov, R.P.; Osmanov, M.A.; Kholmogorov, V.E.

    1987-10-01

    In this paper, processes of photomodification of lymphoid cells in human blood, developing immediately after exposure to visible radiation and also in the late stages after irradiation, were investigated by methods of spontaneous and immune rosette formation and the blast transformation test, combined with treatment with the antioxidant alpha-tocopherol and the radioactive assessment of spontaneous and stimulated DNA synthesis by tritium-thymidine-labelled cells.

  9. Blood-Forming Stem Cell Transplants

    Science.gov (United States)

    ... and suppresses the patient’s immune system to prevent rejection of the transplant. Unlike traditional BMT or PBSCT, ... be given an injection of the donor’s white blood cells. This procedure is called a “ donor ... “tandem transplant” is a type of autologous transplant. This method is being studied ...

  10. Colour measurement and white blood cell recognition

    CERN Document Server

    Gelsema, E S

    1972-01-01

    As a part of a collaboration with NEMCH aimed at the automation of the differential white blood cell count, studies have been made of the different possibilities for using colour to help in the recognition process. Results are presented comparing data obtained with a microspectrophotometer and with a simulated three-colour scanner.

  11. Vascular patterns in the heads of crocodilians: blood vessels and sites of thermal exchange.

    Science.gov (United States)

    Porter, William Ruger; Sedlmayr, Jayc C; Witmer, Lawrence M

    2016-12-01

    Extant crocodilians are a highly apomorphic archosaur clade that is ectothermic, yet often achieve large body sizes that can be subject to higher heat loads. Therefore, the anatomical and physiological roles that blood vessels play in crocodilian thermoregulation need further investigation to better understand how crocodilians establish and maintain cephalic temperatures and regulate neurosensory tissue temperatures during basking and normal activities. The cephalic vascular anatomy of extant crocodilians, particularly American alligator (Alligator mississippiensis) was investigated using a differential-contrast, dual-vascular injection technique and high resolution X-ray micro-computed tomography (μCT). Blood vessels were digitally isolated to create representations of vascular pathways. The specimens were then dissected to confirm CT results. Sites of thermal exchange, consisting of the oral, nasal, and orbital regions, were given special attention due to their role in evaporative cooling and cephalic thermoregulation in other diapsids. Blood vessels to and from sites of thermal exchange were studied to detect conserved vascular patterns and to assess their ability to deliver cooled blood to neurosensory tissues. Within the orbital region, both the arteries and veins demonstrated consistent branching patterns, with the supraorbital, infraorbital, and ophthalmotemporal vessels supplying and draining the orbit. The venous drainage of the orbital region showed connections to the dural sinuses via the orbital veins and cavernous sinus. The palatal region demonstrated a vast plexus that comprised both arteries and veins. The most direct route of venous drainage of the palatal plexus was through the palatomaxillary veins, essentially bypassing neurosensory tissues. Anastomotic connections with the nasal region, however, may provide an alternative route for palatal venous blood to reach neurosensory tissues. The nasal region in crocodilians is probably the most

  12. Cerebral blood flow in sickle cell cerebrovascular disease

    International Nuclear Information System (INIS)

    Huttenlocher, P.R.; Moohr, J.W.; Johns, L.; Brown, F.D.

    1984-01-01

    Cerebral blood flow (CBF) has been studied by the xenon-133 ( 133 Xe) inhalation method in 16 children with suspected sickle cell cerebrovascular disease. Abnormalities consisting of decreases in total, hemispheral, or regional CBF were found in 17 of 26 studies. Eleven studies performed immediately after stroke, transient ischemic attack, or depression of state of alertness showed abnormalities. In addition to confirming regional cerebrovascular insufficiency in children with stroke due to major cerebral artery occlusion, the method detected diffuse decrease in CBF in children with stupor, coma, and seizures who had normal angiographic findings. In contrast, six of seven studies obtained after exchange transfusion or during maintenance on hypertransfusion therapy showed normal findings. The difference between results in patients with acute neurologic disturbances and those receiving transfusion therapy was statistically significant (P less than .005). The data indicate that the 133 Xe method reliably demonstrates cerebrovascular impairment in sickle cell disease. They also suggest that CBF changes in patients with sickle cell disease can be reversed by exchange transfusion and by hypertransfusion therapy. The 133 Xe CBF method may be useful for following up children with sickle cell disease who are at high risk for recurrent stroke

  13. 21 CFR 864.6160 - Manual blood cell counting device.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Manual blood cell counting device. 864.6160 Section 864.6160 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... count red blood cells, white blood cells, or blood platelets. (b) Classification. Class I (general...

  14. Lipid exchange between Borrelia burgdorferi and host cells.

    Directory of Open Access Journals (Sweden)

    Jameson T Crowley

    2013-01-01

    Full Text Available Borrelia burgdorferi, the agent of Lyme disease, has cholesterol and cholesterol-glycolipids that are essential for bacterial fitness, are antigenic, and could be important in mediating interactions with cells of the eukaryotic host. We show that the spirochetes can acquire cholesterol from plasma membranes of epithelial cells. In addition, through fluorescent and confocal microscopy combined with biochemical approaches, we demonstrated that B. burgdorferi labeled with the fluorescent cholesterol analog BODIPY-cholesterol or (3H-labeled cholesterol transfer both cholesterol and cholesterol-glycolipids to HeLa cells. The transfer occurs through two different mechanisms, by direct contact between the bacteria and eukaryotic cell and/or through release of outer membrane vesicles. Thus, two-way lipid exchange between spirochetes and host cells can occur. This lipid exchange could be an important process that contributes to the pathogenesis of Lyme disease.

  15. The antibody approach of labeling blood cells

    Energy Technology Data Exchange (ETDEWEB)

    Srivastava, S.C.

    1991-12-31

    Although the science of blood cell labeling using monoclonal antibodies directed against specific cellular antigens is still in its early stages, considerable progress has recently been accomplished in this area. The monoclonal antibody approach offers the promise of greater selectivity and enhanced convenience since specific cell types can be labeled in vivo, thus eliminating the need for complex and damaging cell separation procedures. This article focuses on these developments with primary emphasis on antibody labeling of platelets and leukocytes. The advantages and the shortcomings of the recently reported techniques are criticality assessed and evaluated.

  16. The antibody approach of labeling blood cells

    Energy Technology Data Exchange (ETDEWEB)

    Srivastava, S.C.

    1991-01-01

    Although the science of blood cell labeling using monoclonal antibodies directed against specific cellular antigens is still in its early stages, considerable progress has recently been accomplished in this area. The monoclonal antibody approach offers the promise of greater selectivity and enhanced convenience since specific cell types can be labeled in vivo, thus eliminating the need for complex and damaging cell separation procedures. This article focuses on these developments with primary emphasis on antibody labeling of platelets and leukocytes. The advantages and the shortcomings of the recently reported techniques are criticality assessed and evaluated.

  17. The antibody approach of labeling blood cells

    Energy Technology Data Exchange (ETDEWEB)

    Srivastava, S.C.

    1992-12-31

    Although the science of blood cell labeling using monoclonal antibodies directed against specific cellular antigens is still in its early stages, considerable progress has recently been accomplished in this area. The monoclonal antibody approach offers the promise of greater selectivity and enhanced convenience since specific cell types can be labeled in vivo, thus eliminating the need for complex and damaging cell separation procedures. This article focuses on these developments with primary emphasis on antibody labeling of platelets and leukocytes. The advantages and the shortcomings of the recently reported techniques are critically assessed and evaluated.

  18. The antibody approach of labeling blood cells

    International Nuclear Information System (INIS)

    Srivastava, S.C.

    1991-01-01

    Although the science of blood cell labeling using monoclonal antibodies directed against specific cellular antigens is still in its early stages, considerable progress has recently been accomplished in this area. The monoclonal antibody approach offers the promise of greater selectivity and enhanced convenience since specific cell types can be labeled in vivo, thus eliminating the need for complex and damaging cell separation procedures. This article focuses on these developments with primary emphasis on antibody labeling of platelets and leukocytes. The advantages and the shortcomings of the recently reported techniques are criticality assessed and evaluated

  19. The antibody approach of labeling blood cells

    International Nuclear Information System (INIS)

    Srivastava, S.C.

    1992-01-01

    Although the science of blood cell labeling using monoclonal antibodies directed against specific cellular antigens is still in its early stages, considerable progress has recently been accomplished in this area. The monoclonal antibody approach offers the promise of greater selectivity and enhanced convenience since specific cell types can be labeled in vivo, thus eliminating the need for complex and damaging cell separation procedures. This article focuses on these developments with primary emphasis on antibody labeling of platelets and leukocytes. The advantages and the shortcomings of the recently reported techniques are critically assessed and evaluated

  20. Comparative study on the effect of radiation on whole blood and isolate red blood cells

    International Nuclear Information System (INIS)

    Selim, N.S.

    2009-01-01

    Assessment of the dielectric properties of red blood cells requires several steps for preparation and isolation from whole blood. These steps may results in changes in the cells properties, and they are time consuming . The present study aims to compare the properties of both whole blood and isolated red blood cells and the effect of gamma radiation on these properties. Adult male rats were exposed to 1, 3.5 and 7 Gy as single dose, from Cs-137 source.The studies dielectric properties, in the frequency range 40 k Hz to 5 MHz, and light scattering studies for suspensions of whole blood and isolated red blood cells from the same groups were measured. The obtained results showed that whole blood and red blood cells suspensions followed the same trend in their response to radiation, which suggests the possibility of using whole blood suspension for the evaluation of the red blood cells properties

  1. Membrane oxygenator heat exchanger failure detected by unique blood gas findings.

    Science.gov (United States)

    Hawkins, Justin L

    2014-03-01

    Failure of components integrated into the cardiopulmonary bypass circuit, although rare, can bring about catastrophic results. One of these components is the heat exchanger of the membrane oxygenator. In this compartment, unsterile water from the heater cooler device is separated from the sterile blood by stainless steel, aluminum, or by polyurethane. These areas are glued or welded to keep the two compartments separate, maintaining sterility of the blood. Although quality control testing is performed by the manufacturer at the factory level, transport presents the real possibility for damage. Because of this, each manufacturer has included in the instructions for use a testing procedure for testing the integrity of the heat exchanger component. Water is circulated through the heat exchanger before priming and a visible check is made of the oxygenator bundle to check for leaks. If none are apparent, then priming of the oxygenator is performed. In this particular case, this procedure was not useful in detecting communication between the water and blood chambers of the oxygenator.

  2. A numerical performance assessment of a commercial cardiopulmonary by-pass blood heat exchanger.

    Science.gov (United States)

    Consolo, Filippo; Fiore, Gianfranco B; Pelosi, Alessandra; Reggiani, Stefano; Redaelli, Alberto

    2015-06-01

    We developed a numerical model, based on multi-physics computational fluid dynamics (CFD) simulations, to assist the design process of a plastic hollow-fiber bundle blood heat exchanger (BHE) integrated within the INSPIRE(TM), a blood oxygenator (OXY) for cardiopulmonary by-pass procedures, recently released by Sorin Group Italia. In a comparative study, we analyzed five different geometrical design solutions of the BHE module. Quantitative geometrical-dependent parameters providing a comprehensive evaluation of both the hemo- and thermo-dynamics performance of the device were extracted to identify the best-performing prototypical solution. A convenient design configuration was identified, characterized by (i) a uniform blood flow pattern within the fiber bundle, preventing blood flow shunting and the onset of stagnation/recirculation areas and/or high velocity pathways, (ii) an enhanced blood heating efficiency, and (iii) a reduced blood pressure drop. The selected design configuration was then prototyped and tested to experimentally characterize the device performance. Experimental results confirmed numerical predictions, proving the effectiveness of CFD modeling as a reliable tool for in silico identification of suitable working conditions of blood handling medical devices. Notably, the numerical approach limited the need for extensive prototyping, thus reducing the corresponding machinery costs and time-to-market. Copyright © 2015 IPEM. Published by Elsevier Ltd. All rights reserved.

  3. Effect of stratified inequality of blood flow on gas exchange in liquid-filled lungs.

    Science.gov (United States)

    West, J. B.; Maloney, J. E.; Castle, B. L.

    1972-01-01

    This investigation set out to answer two questions: (1) are the distal alveoli in the terminal lung units less well perfused than the proximal alveoli, i.e., is there stratification of blood flow; and (2) if so, does this enhance gas exchange in the presence of stratified inequality of ventilation. Excised dog lungs were ventilated with saline and perfused with blood. Following single inspirations of xenon 133 in saline and various periods of breath holding, the expired xenon concentration against volume was measured and it confirmed marked stratified inequality of ventilation under these conditions. By measuring the rate of depletion of xenon from alveoli during a period of blood flow, we showed that the alveoli which emptied at the end of expiration had 16% less blood flow than those exhaling earlier. However, by measuring the xenon concentration in pulmonary venous blood, we found that about 10% less tracer was transferred from the alveoli into the blood when the inspired xenon was stratified within the respiratory zone. Thus while stratification of blood flow was confirmed, it was shown to impair rather than enhance the efficiency of gas transfer.

  4. Responder individuality in red blood cell alloimmunization.

    Science.gov (United States)

    Körmöczi, Günther F; Mayr, Wolfgang R

    2014-11-01

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

  5. Sister chromatid exchanges in X-ray irradiated blood lymphocytes from patients with hereditary diseases with radioresistant DNA synthesis

    International Nuclear Information System (INIS)

    Pleskach, N.M.; Andriadze, M.I.; Mikhel'son, V.M.; Zhestyanikov, V.D.

    1988-01-01

    X-ray irradiation induced sister chromatid exchanges (SCE) in blood lymphocytes from patient with Down's syndrome and adult progeria (in both the cases radioresistant DNA synthesis takes place). In normal lymphocytes (in which ionizing radiation inhibits the replicative synthesis of DNA) the rate of SCE rises with the rise of radiation dose. Thus, the rate of SCE in X-ray irradiated lymphocytes is in reverse dependence with radioresistance of replicative synthesis of DNA. The data obtained are explained in accordance with the replicative hypothesis of the SCE nature (Painter, 1980a): in cells of patients with Down's syndrome, xeroderma pigmentosum from 2 and progeria of adults the time of existence of partly replicated clusters of replicons is decreased due to radioresistant replicative synthesis of DNA, but the presence of partly replicated clusters of replicons in necessary for SCE formation. Therefore the rate of SCF in X-irradiated cells of these patients decreases

  6. Responder Individuality in Red Blood Cell Alloimmunization

    OpenAIRE

    Körmöczi, Günther F.; Mayr, Wolfgang R.

    2014-01-01

    Many different factors influence the propensity of transfusion recipients and pregnant women to form red blood cell alloantibodies (RBCA). RBCA may cause hemolytic transfusion reactions, hemolytic disease of the fetus and newborn and may be a complication in transplantation medicine. Antigenic differences between responder and foreign erythrocytes may lead to such an immune answer, in part with suspected specific HLA class II associations. Biochemical and conformational characteristics of red...

  7. Effect of borax on immune cell proliferation and sister chromatid exchange in human chromosomes.

    Science.gov (United States)

    Pongsavee, Malinee

    2009-10-30

    Borax is used as a food additive. It becomes toxic when accumulated in the body. It causes vomiting, fatigue and renal failure. The heparinized blood samples from 40 healthy men were studied for the impact of borax toxicity on immune cell proliferation (lymphocyte proliferation) and sister chromatid exchange in human chromosomes. The MTT assay and Sister Chromatid Exchange (SCE) technic were used in this experiment with the borax concentrations of 0.1, 0.15, 0.2, 0.3 and 0.6 mg/ml. It showed that the immune cell proliferation (lymphocyte proliferation) was decreased when the concentrations of borax increased. The borax concentration of 0.6 mg/ml had the most effectiveness to the lymphocyte proliferation and had the highest cytotoxicity index (CI). The borax concentrations of 0.15, 0.2, 0.3 and 0.6 mg/ml significantly induced sister chromatid exchange in human chromosomes (P Borax had effects on immune cell proliferation (lymphocyte proliferation) and induced sister chromatid exchange in human chromosomes. Toxicity of borax may lead to cellular toxicity and genetic defect in human.

  8. Effect of borax on immune cell proliferation and sister chromatid exchange in human chromosomes

    Directory of Open Access Journals (Sweden)

    Pongsavee Malinee

    2009-10-01

    Full Text Available Abstract Background Borax is used as a food additive. It becomes toxic when accumulated in the body. It causes vomiting, fatigue and renal failure. Methods The heparinized blood samples from 40 healthy men were studied for the impact of borax toxicity on immune cell proliferation (lymphocyte proliferation and sister chromatid exchange in human chromosomes. The MTT assay and Sister Chromatid Exchange (SCE technic were used in this experiment with the borax concentrations of 0.1, 0.15, 0.2, 0.3 and 0.6 mg/ml. Results It showed that the immune cell proliferation (lymphocyte proliferation was decreased when the concentrations of borax increased. The borax concentration of 0.6 mg/ml had the most effectiveness to the lymphocyte proliferation and had the highest cytotoxicity index (CI. The borax concentrations of 0.15, 0.2, 0.3 and 0.6 mg/ml significantly induced sister chromatid exchange in human chromosomes (P Conclusion Borax had effects on immune cell proliferation (lymphocyte proliferation and induced sister chromatid exchange in human chromosomes. Toxicity of borax may lead to cellular toxicity and genetic defect in human.

  9. Evaluation of red blood cell stability during immersion blood warming

    African Journals Online (AJOL)

    Method: Blood, three days after donation (fresh blood), with CPD anticoagulant, was warmed at 37°C, 43°C, 45°C, 47°C, 50°C and 55°C for 10, 20, 30 and 60 minutes and analysed for haemolysis. In addition, the biochemical markers were done on the blood after 34 days of storage at 4°C (old blood). Temperature increase ...

  10. The use of prophylactic partial exchange tranfusion in pregnancies associated with sickle cell hemoglobinopathies.

    Science.gov (United States)

    Morrison, J C; Wiser, W L

    1976-11-01

    Sickle cell anemia is associated with an alarming attrition rate during pregnancy. The maternal morbidity rate, perinatal wastage rate, and the incidence of severe morbidity in both mother and child are elevated above acceptable limits. In most cases, these statistics have been compiled using conservative therapeutic modalities. In contrast, this report utilizes prophylactic partial exchange transfusion therapy in patients with severe sickle cell hemoglobinopathies. The protocol involves the introduction of 750-1000 cc of buffy coat, poor washed red cells exchanged with 1000-1500 cc whole blood during phlebotomy at 28 weeks' gestation and again prior to term. Thirty-six consecutive pregnant patients with sickle cell anemia have been managed in this fashion. The one maternal mortality occurred in a patient who did not complete the protocol. Major maternal morbidity and perinatal wastage rates were significantly decreased. Two cases of serum hepatitis occurred. It appears from these data that the use of prophylactic partial exchange transfusion in pregnant patients with severe sickle cell hemoglobinopathies can be of benefit. Further trials of this method seem justified by these results to assess completely the benefit-risk ratio of this procedure.

  11. Binding Characteristics Of Ivermectin To Blood Cells | Nweke ...

    African Journals Online (AJOL)

    The binding characteristics of Ivermectin were determined using scatchard plots. The percentage binding to platelet rich plasma, white blood cells and red blood cells were 90.00 + 1.00, 96-90 + 1.05 and 46.20 + 1.10 S.D respectively. It was found to bind the highest to white blood cells and the least to red blood cells.

  12. Radiolabeled blood cells: radiation dosimetry and significance

    International Nuclear Information System (INIS)

    Thakur, M.L.

    1986-01-01

    Over the past few years blood cells labeled with In-111 have become increasingly useful in clinical diagnosis and biomedical research. Indium-111 by the virtue of its physical characteristics and ability to bind to cell cytoplasmic components, provides an excellent cell tracer and thereby, allows investigators to monitor in vivo cell distribution by external imaging and help determine a course of regimen in treating life threatening diseases. Due to natural phenomena such as margination, blood pool, and reticuloendothelial cell activity, in the normal state, depending upon the cell type and the quality of cell preparations, 30%-50% of the administered radioactivity is immediately distributed in the liver, spleen and bone marrow. Over a period of time the radioactivity in these organs slightly increases and decays with a physical half-life of In-111. The resulting radiation dose to these organs ranges between 1-25 rads/mCi In-111 administered. The authors have developed a new In-111 labeling technique which preserves platelet ultrastructure and shown that human lymphocytes labeled with In-111 in mixed leukocytes preparations a) are only 0.003% of the total -body lymphocytes population and b) are killed. The consequence if any may be considered insignificant, particularly because 5.6% metaphases from normal men and 6.5% metaphases from normal women in the US have at least one chromosome aberration. Calculations have shown that the risk of fatal hematological malignancy, over a 30 year period, in recipients of 100 million lymphocytes labeled with 100 μCi In-111 is 1/million patients studied. This risk is less than 0.025% of the 1981 spontaneous cancer patient rate in the country. 32 references, 10 tables

  13. Molecular mechanisms of disease in hereditary red blood cell enzymopathies

    NARCIS (Netherlands)

    Wijk, Henricus Anthonius van

    2004-01-01

    Metabolically defective red blood cells are old before their time, and suffer from metabolic progeria. The focus of this thesis was to identify the molecular mechanisms by which inherited enzymopathies of the red blood cell lead to impaired enzyme function and, consequently, shorten red blood cell

  14. 21 CFR 864.7100 - Red blood cell enzyme assay.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Red blood cell enzyme assay. 864.7100 Section 864... enzyme assay. (a) Identification. Red blood cell enzyme assay is a device used to measure the activity in... kinase or 2,3-diphosphoglycerate. A red blood cell enzyme assay is used to determine the enzyme defects...

  15. 21 CFR 660.30 - Reagent Red Blood Cells.

    Science.gov (United States)

    2010-04-01

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

  16. Red blood cell in simple shear flow

    Science.gov (United States)

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

    2013-03-01

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

  17. Mechanosensing Dynamics of Red blood Cells

    Science.gov (United States)

    Wan, Jiandi

    2015-11-01

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

  18. Platelet adhesion onto artificial red blood cells.

    Science.gov (United States)

    Muramatsu, N; Kondo, T

    1980-05-01

    Several kinds of polyamide microcapsules containing mammalian hemolysate were prepared by making use of the interfacial polycondensation reaction between diamines and terephthaloyl dichloride and their blood compatibility in terms of platelet adhesion was examined aiming at their ultimate clinical use as artificial red blood cells. It was found that rabbit platelets adhere onto the hemolysate-loaded microcapsules in the presence of the plasma, while no platelet adhesion takes place in the absence of the plasma. This was interpreted as indicating an important role of plasma components in platelet adhesion. Moreover, platelet adhesion was observed to be facilitated by negative charges on the surface of the hemolysate-loaded microcapsules; the more negatively the surface was charge, the more easily the platelets adhered onto the surface. Finally, the present method of assessing platelet adhesion suggested the possibility of its use for kinetic study of platelet adhesion since it allowedus to make numerical evaluation of platelet adhesion as a function of time.

  19. Ventilation, gas exchange and blood gases in the snake, Pituophis melanoleucus.

    Science.gov (United States)

    Stinner, J N

    1982-03-01

    Oxygen consumption of Pituophis melanoleucus was about 30-50% of values predicted for snakes of similar body mass. Following a rise in body temperature there were transient increases in CO2 elimination and the respiratory exchange ratio for about 6 hours. Lowering body temperature produced transient decreases in CO2 elimination and the respiratory exchange ratio for about 24 hours. Respiratory exchange ratios measured up to 6 days following these transients were found to be significantly higher at higher temperatures. From 20 to 30 degrees C arterial pH declined 0.157 unit, and there was a significant decline in blood CO2 of 1.3 mM which is consistent with the direction of the transients in CO2 elimination. This fall in CO2 at higher temperatures probably results from increased levels of plasma fixed acid (e.g., lactate). Minute ventilation and breathing frequency increased with body temperature while tidal volume remained nearly constant at 29 ml/kg. Breathing was regular, with each breath followed by an inspiratory pause. Air convection requirement declined from about 61 ml air/ml O2 at 15 degrees C to 36 ml air/ml O2 at 30 degrees C. Blood convection requirement remained constant at about 44.6 ml blood/ml O2 at 20 degrees C and 30 degrees C with the result that ventilation/perfusion declined from approximately 1.13 to 0.76. In Pituophis, mechanisms of acid-base regulation and adjustments in gas transfer with temperature do not differ fundamentally from those of other air-breathing ectotherms. However, snakes utilize tidal volumes which are 2 to 2.5 times larger than other reptiles and have air convection requirements which exceed other reptiles by about 50%.

  20. Highly durable direct hydrazine hydrate anion exchange membrane fuel cell

    Science.gov (United States)

    Sakamoto, Tomokazu; Serov, Alexey; Masuda, Teruyuki; Kamakura, Masaki; Yoshimoto, Koji; Omata, Takuya; Kishi, Hirofumi; Yamaguchi, Susumu; Hori, Akihiro; Horiuchi, Yousuke; Terada, Tomoaki; Artyushkova, Kateryna; Atanassov, Plamen; Tanaka, Hirohisa

    2018-01-01

    The factors influenced on degradation of direct hydrazine hydrate fuel cells (DHFCs) under operation conditions are analyzed by in situ soft X-ray radiography. A durability of DHFCs is significantly improved by multi-step reaction DHFCs (MSR-DHFCs) approach designed to decrease the crossover of liquid fuel. An open circuit voltage (OCV) as well as cell voltage at 5 mA cm-2 of MSR-DHFC construct with commercial anion exchange membrane (AEM) maintained for over of 3500 h at 60 °C. Furthermore, the commercial proton exchange membrane (PEM) is integrated into AEM of MSR-DHFCs resulting in stable power output of MSR-DHFCs for over than 2800 h at 80 °C.

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

    Science.gov (United States)

    Ebine, Kunio

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

  2. Changes in pulmonary blood flow do not affect gas exchange during intermittent ventilation in resting turtles

    DEFF Research Database (Denmark)

    Wang, Tobias; Hicks, James W.

    2008-01-01

    The breathing pattern of many different air-breathing vertebrates, including lungfish, anuran amphibians, turtles, crocodiles and snakes, is characterized by brief periods of lung ventilation interspersed among apnoeas of variable duration. These intermittent ventilatory cycles are associated...... experimentally. The present study measured pulmonary gas exchange in fully recovered, freely diving turtles, where changes in pulmonary blood flow were prevented by partial occlusion of the pulmonary artery. Prevention of L-R shunt during ventilation did not impair CO2 excretion and overall, oxygen uptake and CO...

  3. Thrombocytopenia responding to red blood cell transfusion

    International Nuclear Information System (INIS)

    Mubarak, Ahmad A.; Awidi, Abdalla; Rasul, Kakil I.; Al-Homsi, Ussama

    2004-01-01

    Three patients with severe symptomatic iron defficiency anemia and thrombocytopenia had a significant rise in the platelet count a few days following packed red blood cell transfusion. Pretransfusion platelet count of of patient one was 17x10/L. 22x10/Lin patient two and 29x10/L in patient three. On the 6th day of post tranfusion, the platelet count rose to 166x10/Lin patient one, 830x10/L in patient two and 136x10/L in patient three. The possible mechcnism behind such an unreported observation are discussed. (author)

  4. Proton Exchange Membrane Fuel Cell Reversal: A Review

    Directory of Open Access Journals (Sweden)

    Congwei Qin

    2016-12-01

    Full Text Available The H2/air-fed proton exchange membrane fuel cell (PEMFC has two major problems: cost and durability, which obstruct its pathway to commercialization. Cell reversal, which would create irreversible damage to the fuel cell and shorten its lifespan, is caused by reactant starvation, load change, low catalyst performance, and so on. This paper will summarize the causes, consequences, and mitigation strategies of cell reversal of PEMFC in detail. A description of potential change in the anode and cathode and the differences between local starvation and overall starvation are reviewed, which gives a framework for comprehending the origins of cell reversal. According to the root factor of cell starvation, i.e., fuel cells do not satisfy the requirements of electrons and protons of normal anode and cathode chemical reactions, we will introduce specific methods to mitigate or prevent fuel cell damage caused by cell reversal in the view of system management strategies and component material modifications. Based on a comprehensive understanding of cell reversal, it is beneficial to operate a fuel cell stack and extend its lifetime.

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

    Science.gov (United States)

    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.

  6. A direct ascorbate fuel cell with an anion exchange membrane

    Science.gov (United States)

    Muneeb, Omar; Do, Emily; Tran, Timothy; Boyd, Desiree; Huynh, Michelle; Ghosn, Gregory; Haan, John L.

    2017-05-01

    Ascorbic Acid (Vitamin C) is investigated as a renewable alternative fuel for alkaline direct liquid fuel cells (DLFCs). The environmentally- and biologically-friendly compound, L-ascorbic acid (AA) has been modeled and studied experimentally under acidic fuel cell conditions. In this work, we demonstrate that ascorbic acid is a more efficient fuel in alkaline media than in acidic media. An operating direct ascorbate fuel cell is constructed with the combination of L-ascorbic acid and KOH as the anode fuel, air or oxygen as the oxidant, a polymer anion exchange membrane, metal or carbon black anode materials and metal cathode catalyst. Operation of the fuel cell at 60 °C using 1 M AA and 1 M KOH as the anode fuel and electrolyte, respectively, and oxygen gas at the cathode, produces a maximum power density of 73 mW cm-2, maximum current density of 497 mA cm-2 and an open circuit voltage of 0.90 V. This performance is significantly greater than that of an ascorbic acid fuel cell with a cation exchange membrane, and it is competitive with alkaline DLFCs fueled by alcohols.

  7. Isolation of mesenchymal stem cells from equine umbilical cord blood

    DEFF Research Database (Denmark)

    Koch, Thomas Gadegaard; Heerkens, Tammy; Thomsen, Preben Dybdahl

    2007-01-01

    . The hypothesis of this study was that equine MSCs could be isolated from fresh whole equine cord blood. Results: Cord blood was collected from 7 foals immediately after foaling. The mononuclear cell fraction was isolated by Ficoll density centrifugation and cultured in a DMEM low glucose based media at 38.5o......Background: There are no published studies on stem cells from equine cord blood although commercial storage of equine cord blood for future autologous stem cell transplantations is available. Mesenchymal stem cells (MSC) have been isolated from fresh umbilical cord blood of humans collected non......-invasively at the time of birth and from sheep cord blood collected invasively by a surgical intrauterine approach. Mesenchymal stem cells isolation percentage from frozen-thawed human cord blood is low and the future isolation percentage of MSCs from cryopreserved equine cord blood is therefore expectedly low...

  8. The Radiation Effect on Peripheral Blood Cell

    International Nuclear Information System (INIS)

    Lee, Tae June; Kwon, Hyoung Cheol; Kim, Jung Soo; Im, Sun Kyun; Choi, Ki Chul

    1988-01-01

    To evaluate radiation effect on the hematopoietic system, we analyzed 44 patients who were treated with conventionally fractionated radiation therapy (RT) at Chonbuk National University Hospital. According to the treatment sites, we classified them into three groups: group I as head and neck, group II as thorax, and group III as pelvis. White blood cell, lymphocyte, platelet and hemoglobin were checked before and during RT The results were as follow; 1. White blood cell (WBC) and lymphocyte count were declined from the first week of RT to the third week, and then slightly recovered after the third or fourth week. There was prominent decrease in lymphocyte counts than WBC. 2. Platelet counts were declined until the second week of the RT, showed slight recovery at fourth week in all groups. Hemoglobin values were slightly decreased in the first week and then recovered the level of pretreatment value, gradually. 3. Lymphocyte count were declined significantly on group III(p<0.01), WBC and platelet counts were decreased on group II but statistically not significant

  9. Haemocompatibility and ion exchange capability of nanocellulose polypyrrole membranes intended for blood purification

    Science.gov (United States)

    Ferraz, Natalia; Carlsson, Daniel O.; Hong, Jaan; Larsson, Rolf; Fellström, Bengt; Nyholm, Leif; Strømme, Maria; Mihranyan, Albert

    2012-01-01

    Composites of nanocellulose and the conductive polymer polypyrrole (PPy) are presented as candidates for a new generation of haemodialysis membranes. The composites may combine active ion exchange with passive ultrafiltration, and the large surface area (about 80 m2 g−1) could potentially provide compact dialysers. Herein, the haemocompatibility of the novel membranes and the feasibility of effectively removing small uraemic toxins by potential-controlled ion exchange were studied. The thrombogenic properties of the composites were improved by applying a stable heparin coating. In terms of platelet adhesion and thrombin generation, the composites were comparable with haemocompatible polymer polysulphone, and regarding complement activation, the composites were more biocompatible than commercially available membranes. It was possible to extract phosphate and oxalate ions from solutions with physiological pH and the same tonicity as that of the blood. The exchange capacity of the materials was found to be 600 ± 26 and 706 ± 31 μmol g−1 in a 0.1 M solution (pH 7.4) and in an isotonic solution of phosphate, respectively. The corresponding values with oxalate were 523 ± 5 in a 0.1 M solution (pH 7.4) and 610 ± 1 μmol g−1 in an isotonic solution. The heparinized PPy–cellulose composite is consequently a promising haemodialysis material, with respect to both potential-controlled extraction of small uraemic toxins and haemocompatibility. PMID:22298813

  10. Modeling Of Proton Exchange Membrane Fuel Cell Systems

    DEFF Research Database (Denmark)

    Nielsen, Mads Pagh

    The objective of this doctoral thesis was to develop reliable steady-state and transient component models suitable to asses-, develop- and optimize proton exchange membrane (PEM) fuel cell systems. Several components in PEM fuel cell systems were characterized and modeled. The developed component......- and system models match experimental data from the literature. However, limited data were available for verification so further work is necessary to confirm detailed aspects of the models. It is nonetheless expected that the developed models will be useful for system modeling and optimization of PEM fuel...... cell systems. Consequences of indirectly fueling PEM stacks with hydrocarbons using reforming technology were investigated using a PEM stack model including CO poisoning kinetics and a transient Simulink steam reforming system model. Aspects regarding the optimization of PEM fuel cell systems...

  11. A Novel Unitized Regenerative Proton Exchange Membrane Fuel Cell

    Science.gov (United States)

    Murphy, O. J.; Cisar, A. J.; Gonzalez-Martin, A.; Salinas, C. E.; Simpson, S. F.

    1996-01-01

    A difficulty encountered in designing a unitized regenerative proton exchange membrane (PEM) fuel cell lies in the incompatibility of electrode structures and electrocatalyst materials optimized for either of the two functions (fuel cell or electrolyzer) with the needs of the other function. This difficulty is compounded in previous regenerative fuel cell designs by the fact that water, which is needed for proton conduction in the PEM during both modes of operation, is the reactant supplied to the anode in the electrolyzer mode of operation and the product formed at the cathode in the fuel cell mode. Drawbacks associated with existing regenerative fuel cells have been addressed. In a first innovation, electrodes function either as oxidation electrodes (hydrogen ionization or oxygen evolution) or as reduction electrodes (oxygen reduction or hydrogen evolution) in the fuel cell and electrolyzer modes, respectively. Control of liquid water within the regenerative fuel cell has been brought about by a second innovation. A novel PEM has been developed with internal channels that permit the direct access of water along the length of the membrane. Lateral diffusion of water along the polymer chains of the PEM provides the water needed at electrode/PEM interfaces. Fabrication of the novel single cell unitized regenerative fuel cell and results obtained on testing it are presented.

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

    DEFF Research Database (Denmark)

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

    2008-01-01

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

  13. Ecto-ATPase activity of vertebrate blood cells.

    Science.gov (United States)

    Bencic, D C; Yates, T J; Ingermann, R L

    1997-01-01

    Ecto-ATPase activity was measured for red blood cells, white blood cells, and whole blood from a variety of vertebrates. A large range of red blood cell ecto-ATPase activity was observed; for example, at 10 degrees C, red blood cells from a catastomid fish (Catostomus macrocheilus) and a newt (Taricha rivularis) had activities of 56 +/- 9 and 25,000,000 +/- 14,000,000 pmol ATP per 10(6) red blood cells per hour, respectively (mean +/- SD). Several control experiments verified that the measured ATPase activity was not the result of intracellular ATPases released due to cell damage or lysis nor due to the release of intracellular nucleoside triphosphate or uptake of extracellular ATP. Red blood cell ecto-ATPase activity was relatively low within the teleosts, was high within the reptiles, and had the greatest range and single highest value within the amphibians. Within the endotherms, avian red blood cell ecto-ATPase activities were greater than mammalian red blood cell ecto-ATPase activities, which were the lowest for all vertebrates examined. The lowest ecto-ATPase activities measured were for human and skunk red blood cells, which had activities of 13 +/- 1 and 11 +/- 2 pmol ATP per 10(6) red blood cells per hour, respectively, at 35 degrees C. Ecto-ATPase activity was measured in white blood cells of several vertebrate species and appeared generally high and less variable than red blood cell ecto-ATPase activity. Measured whole blood ecto-ATPase activity showed a range of three orders of magnitude and correlated positively with red blood cell ecto-ATPase activities. Ecto-ATPase activity was also determined for red blood cells from fetal, 1-3 d old neonatal, and pregnant garter snakes (Thamnophis elegans); these activities were not significantly different from the activity of red blood cells from nonpregnant adult females. Overall, the data from the present study demonstrate a wide range of red blood cell and whole blood ecto-ATPase activities among vertebrates

  14. DEVELOPMENT OF NOVEL ELECTROCATALYSTS FOR PROTON EXCHANGE MEMBRANE FUEL CELLS

    Energy Technology Data Exchange (ETDEWEB)

    Shamsuddin Ilias

    2003-04-24

    Fuel cells are electrochemical devices that convert the available chemical free energy directly into electrical energy, without going through heat exchange process. Of all different types of fuel cells, the Proton Exchange Membrane Fuel Cell (PEMFC) is one of the most promising power sources for stand-alone utility and electric vehicle applications. Platinum (Pt) Catalyst is used for both fuel and air electrodes in PEMFCs. However, carbon monoxide (CO) contamination of H{sub 2} greatly affects electro catalysts used at the anode of PEMFCs and decreases cell performance. The irreversible poisoning of the anode can occur even in CO concentrations as low as few parts per million (ppm). In this work, we have synthesized several novel elctrocatalysts (Pt/C, Pt/Ru/C, Pt/Mo/C, Pt/Ir and Pt/Ru/Mo) for PEMFCs. These catalysts have been tested for CO tolerance in the H{sub 2}/air fuel cell, using CO concentrations in the H{sub 2} fuel that varies from 10 to 100 ppm. The performance of the electrodes was evaluated by determining the cell potential against current density. The effects of catalyst composition and electrode film preparation method on the performance of PEM fuel cell were also studied. It was found that at 70 C and 3.5 atm pressure at the cathode, Pt-alloy catalyst (10 wt% Pt/Ru/C, 20 wt% Pt/Mo/C) were more CO tolerant than the 20 wt% Pt/C catalyst alone. It was also observed that spraying method was better than the brushing technique for the preparation of electrode film.

  15. Services to Operate a Red Blood Cell Storage Laboratory

    National Research Council Canada - National Science Library

    Lippert, Lloyd

    1999-01-01

    The Bionetics Corporation staffed and maintained laboratories to support red blood cell preservation research for the Blood Research Detachment, Walter Reed Army Institute of Research, initially at 1413 Research Blvd...

  16. Transient response of a proton exchange membrane fuel cell

    Science.gov (United States)

    Weydahl, Helge; Møller-Holst, Steffen; Hagen, Georg; Børresen, Børre

    The transient response of a proton exchange membrane fuel cell (PEMFC) supplied with pure hydrogen and oxygen was investigated by load step measurements assisted by electrochemical impedance spectroscopy and chronoamperometry. Using an in-house designed resistance board, the uncontrolled response in both cell voltage and current upon step changes in a resistive load was observed. The PEMFC was found to respond quickly and reproducibly to load changes. The transient PEMFC response was limited by a cathodic charge transfer process with a potential-dependent response time. For load steps to high-current densitities, a second transient process with a constant response time was observed. This transient was offset from the charge transfer transient by a temporarily stable plateau. Results from chronoamperometry indicated that the second transient could be related to a diffusion process. Transient paths were plotted in the V- i diagram, matching a predicted pattern with overshooting cell voltage and current during a load step.

  17. Percolation in a Proton Exchange Membrane Fuel Cell Catalyst Layer

    Energy Technology Data Exchange (ETDEWEB)

    Stacy, Stephen; Allen, Jeffrey

    2012-07-01

    Water management in the catalyst layers of proton exchange membrane fuel cells (PEMFC) is confronted by two issues, flooding and dry out, both of which result in improper functioning of the fuel cell and lead to poor performance and degradation. At the present time, the data that has been reported about water percolation and wettability within a fuel cell catalyst layer is limited. A method and apparatus for measuring the percolation pressure in the catalyst layer has been developed based upon an experimental apparatus used to test water percolation in porous transport layers (PTL). The experimental setup uses a pseudo Hele-Shaw type testing where samples are compressed and a fluid is injected into the sample. Testing the samples gives percolation pressure plots which show trends in increasing percolation pressure with an increase in flow rate. A decrease in pressure was seen as percolation occurred in one sample, however the pressure only had a rising effect in the other sample.

  18. Red blood cell transfusion in septic shock

    DEFF Research Database (Denmark)

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

    2014-01-01

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

  19. Red blood cell transfusion in septic shock

    DEFF Research Database (Denmark)

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

    2014-01-01

    BACKGROUND: Treating anaemia with red blood cell (RBC) transfusion is frequent, but controversial, in patients with septic shock. Therefore we assessed characteristics and outcome associated with RBC transfusion in this group of high risk patients. METHODS: We did a prospective cohort study at 7...... general intensive care units (ICUs) including all adult patients with septic shock in a 5-month period. RESULTS: Ninety-five of the 213 included patients (45%) received median 3 (interquartile range 2-5) RBC units during shock. The median pre-transfusion haemoglobin level was 8.1 (7.4-8.9) g...... and SAPS II and SOFA-score on day 1. CONCLUSIONS: The decision to transfuse patients with septic shock was likely affected by disease severity and bleeding, but haemoglobin level was the only measure that consistently differed between transfused and non-transfused patients....

  20. Numerical analysis on cell-cell interaction of red blood cells during sedimentation

    Science.gov (United States)

    Shi, Xing

    2017-07-01

    The long-range hydrodynamic interaction among red blood cells plays an important role on the macroscopic behaviors, however, the molecular interaction at such scale is much weaker. In this paper, the sedimentations under external body force of two red blood cells are numerical simulated to investigate the hydrodynamic interaction between cells. The flow is solved by lattice Boltzmann method and the membrane of red blood cell is model by the spring model where the fluid-membrane interaction is coupled by fictitious domain method. It is found that the cells have the tendency to aggregate and may be aligned in a line along the sediment direction. Compared to the properties of a single cell under the same conditions, the sediment velocity of red blood cell group is larger; the leading cell deforms less and the following cell endures larger deformation.

  1. Development of Passive Fuel Cell Thermal Management Heat Exchanger

    Science.gov (United States)

    Burke, Kenneth A.; Jakupca, Ian J.; Colozza, Anthony J.

    2010-01-01

    The NASA Glenn Research Center is developing advanced passive thermal management technology to reduce the mass and improve the reliability of space fuel cell systems for the NASA Exploration program. The passive thermal management system relies on heat conduction within highly thermally conductive cooling plates to move the heat from the central portion of the cell stack out to the edges of the fuel cell stack. Using the passive approach eliminates the need for a coolant pump and other cooling loop components within the fuel cell system which reduces mass and improves overall system reliability. Previous development demonstrated the performance of suitable highly thermally conductive cooling plates that could conduct the heat, provide a sufficiently uniform temperature heat sink for each cell of the fuel cell stack, and be substantially lighter than the conventional thermal management approach. Tests were run with different materials to evaluate the design approach to a heat exchanger that could interface with the edges of the passive cooling plates. Measurements were made during fuel cell operation to determine the temperature of individual cooling plates and also to determine the temperature uniformity from one cooling plate to another.

  2. Proton exchange membrane fuel cell technology for transportation applications

    Energy Technology Data Exchange (ETDEWEB)

    Swathirajan, S. [General Motors R& D Center, Warren, MI (United States)

    1996-04-01

    Proton Exchange Membrane (PEM) fuel cells are extremely promising as future power plants in the transportation sector to achieve an increase in energy efficiency and eliminate environmental pollution due to vehicles. GM is currently involved in a multiphase program with the US Department of Energy for developing a proof-of-concept hybrid vehicle based on a PEM fuel cell power plant and a methanol fuel processor. Other participants in the program are Los Alamos National Labs, Dow Chemical Co., Ballard Power Systems and DuPont Co., In the just completed phase 1 of the program, a 10 kW PEM fuel cell power plant was built and tested to demonstrate the feasibility of integrating a methanol fuel processor with a PEM fuel cell stack. However, the fuel cell power plant must overcome stiff technical and economic challenges before it can be commercialized for light duty vehicle applications. Progress achieved in phase I on the use of monolithic catalyst reactors in the fuel processor, managing CO impurity in the fuel cell stack, low-cost electrode-membrane assembles, and on the integration of the fuel processor with a Ballard PEM fuel cell stack will be presented.

  3. Tandem cathode for proton exchange membrane fuel cells

    DEFF Research Database (Denmark)

    Siahrostami, Samira; Björketun, Mårten E.; Strasser, Peter

    2013-01-01

    The efficiency of proton exchange membrane fuel cells is limited mainly by the oxygen reduction reaction at the cathode. The large cathodic overpotential is caused by correlations between binding energies of reaction intermediates in the reduction of oxygen to water. This work introduces a novel...... reaction intermediate each, and they occur on different catalyst surfaces. As a result they can be optimized independently and the fundamental problem associated with the four-electron catalysis is avoided. A combination of density functional theory calculations and published experimental data is used...

  4. Construction and evaluation of a proton exchange fuel cell

    International Nuclear Information System (INIS)

    Gutierrez, Omar; Monsalve, Carlos; Trujillo, Gonzalo; Hoyos, Bibian; Sanchez, Carlos; Gonzalez, Javier

    2005-01-01

    One design of a hydrogen proton exchange membrane fuel cell (PEMFC) is proposed. Porous carbon supported platinum electrodes were manufactured by impregnation, reduction and hot-press methods; noble metal loading of 0.4 mg/cm 2 was achieved. The conditions to obtain the porous support were: composition of 15 % Teflon and 85 % carbon, pressure of 100 Kgf/cm 2 , temperature of 300 Celsius degrade and 20 minutes of hot-pressing. The pattern of gas flow distribution was made possible by machined interdigitated channels into conductor graphite plates. Several tests were run varying the load resistance to obtain the polarization curves. Comparison with a commercial PEMFC is also made

  5. Preoperative blood transfusions for sickle cell disease

    Science.gov (United States)

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

    2016-01-01

    Background Sickle cell disease is one of the commonest severe monogenic disorders in the world, due to the inheritance of two abnormal haemoglobin (beta globin) genes. Sickle cell disease can cause severe pain, significant end-organ damage, pulmonary complications, and premature death. Surgical interventions are more common in people with sickle cell disease, and occur at much younger ages than in the general population. Blood transfusions are frequently used prior to surgery and several regimens are used but there is no consensus over the best method or the necessity of transfusion in specific surgical cases. This is an update of a Cochrane review first published in 2001. Objectives To determine whether there is evidence that preoperative blood transfusion in people with sickle cell disease undergoing elective or emergency surgery reduces mortality and perioperative or sickle cell-related serious adverse events. To compare the effectiveness of different transfusion regimens (aggressive or conservative) if preoperative transfusions are indicated in people with sickle cell disease. Search methods We searched for relevant trials in The Cochrane Library, MEDLINE (from 1946), Embase (from 1974), the Transfusion Evidence Library (from 1980), and ongoing trial databases; all searches current to 23 March 2016. We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Trials Register: 18 January 2016. Selection criteria All randomised controlled trials and quasi-randomised controlled trials comparing preoperative blood transfusion regimens to different regimens or no transfusion in people with sickle cell disease undergoing elective or emergency surgery. There was no restriction by outcomes examined, language or publication status. Data collection and analysis Two authors independently assessed trial eligibility and the risk of bias and extracted data. Main results Three trials with 990 participants were eligible for inclusion in the review. There were no

  6. Shape-Shifted Red Blood Cells: A Novel Red Blood Cell Stage?

    Science.gov (United States)

    Chico, Verónica; Puente-Marin, Sara; Nombela, Iván; Ciordia, Sergio; Mena, María Carmen; Carracedo, Begoña; Villena, Alberto; Mercado, Luis; Coll, Julio; Ortega-Villaizan, María Del Mar

    2018-04-19

    Primitive nucleated erythroid cells in the bloodstream have long been suggested to be more similar to nucleated red cells of fish, amphibians, and birds than the red cells of fetal and adult mammals. Rainbow trout Ficoll-purified red blood cells (RBCs) cultured in vitro undergo morphological changes, especially when exposed to stress, and enter a new cell stage that we have coined shape-shifted RBCs (shRBCs). We have characterized these shRBCs using transmission electron microscopy (TEM) micrographs, Wright⁻Giemsa staining, cell marker immunostaining, and transcriptomic and proteomic evaluation. shRBCs showed reduced density of the cytoplasm, hemoglobin loss, decondensed chromatin in the nucleus, and striking expression of the B lymphocyte molecular marker IgM. In addition, shRBCs shared some features of mammalian primitive pyrenocytes (extruded nucleus surrounded by a thin rim of cytoplasm and phosphatidylserine (PS) exposure on cell surface). These shRBCs were transiently observed in heat-stressed rainbow trout bloodstream for three days. Functional network analysis of combined transcriptomic and proteomic studies resulted in the identification of proteins involved in pathways related to the regulation of cell morphogenesis involved in differentiation, cellular response to stress, and immune system process. In addition, shRBCs increased interleukin 8 (IL8), interleukin 1 β (IL1β), interferon ɣ (IFNɣ), and natural killer enhancing factor (NKEF) protein production in response to viral hemorrhagic septicemia virus (VHSV). In conclusion, shRBCs may represent a novel cell stage that participates in roles related to immune response mediation, homeostasis, and the differentiation and development of blood cells.

  7. Self-Sorting of White Blood Cells in a Lattice

    Science.gov (United States)

    Carlson, Robert H.; Gabel, Christopher V.; Chan, Shirley S.; Austin, Robert H.; Brody, James P.; James, D. W. Winkelman M.

    1997-09-01

    When a drop of human blood containing red and white blood cells is forced to move via hydrodynamic forces in a lattice of channels designed to mimic the capillary channels, the white cells self-fractionate into the different types of white cells. The pattern of white cells that forms is due to a combination of stretch-activated adhesion of cells with the walls, stochastic sticking probabilities, and heteroavoidance between granulocytes and lymphocytes.

  8. The effects of blood and blood products on the arachnoid cell.

    Science.gov (United States)

    Hansen, Eric A; Romanova, Liudmila; Janson, Christopher; Lam, Cornelius H

    2017-06-01

    After traumatic brain injury (TBI), large amounts of red blood cells and hemolytic products are deposited intracranially creating debris in the cerebrospinal fluid (CSF). This debris, which includes heme and bilirubin, is cleared via the arachnoid granulations and lymphatic systems. However, the mechanisms by which erythrocytes and their breakdown products interfere with normal CSF dynamics remain poorly defined. The purpose of this study was to model in vitro how blood breakdown products affect arachnoid cells at the CSF-blood barrier, and the extent to which the resorption of CSF into the venous drainage system is mechanically impaired following TBI. Arachnoid cells were grown to confluency on permeable membranes. Rates of growth and apoptosis were measured in the presence of blood and lysed blood, changes in transepithelial electrical resistance (TEER) was measured in the presence of blood and hemoglobin, and small molecule permeability was determined in the presence of blood, lysed blood, bilirubin, and biliverdin. These results were directly compared with an established rat brain endothelial cell line (RBEC4) co-cultured with rat brain astrocytes. We found that arachnoid cells grown in the presence of whole or lysed erythrocytes had significantly slower growth rates than controls. Bilirubin and biliverdin, despite their low solubilities, altered the paracellular transport of arachnoid cells more than the acute blood breakdown components of whole and lysed blood. Mannitol permeability was up to four times higher in biliverdin treatments than controls, and arachnoid membranes demonstrated significantly decreased small molecule permeabilities in the presence of whole and lysed blood. We conclude that short-term (5 days) arachnoid cell viability are affected by blood and blood breakdown products, with important consequences for CSF flow and blood clearance after TBI.

  9. Effect on osmotic fragility of red blood cells of whole blood submitted ...

    African Journals Online (AJOL)

    Whole body vibration (WBV) exercises in oscillating platforms (OP) have emerged in sports and in the rehabilitation procedures of clinical disorders. The aim of this work was to verify the effects of vibrations on the osmotic fragility (OF) of red blood cells (RBC) isolated from whole blood submitted to OP. Heparinized blood ...

  10. Phenotype and functions of memory Tfh cells in human blood.

    Science.gov (United States)

    Schmitt, Nathalie; Bentebibel, Salah-Eddine; Ueno, Hideki

    2014-09-01

    Our understanding of the origin and functions of human blood CXCR5(+) CD4(+) T cells found in human blood has changed dramatically in the past years. These cells are currently considered to represent a circulating memory compartment of T follicular helper (Tfh) lineage cells. Recent studies have shown that blood memory Tfh cells are composed of phenotypically and functionally distinct subsets. Here, we review the current understanding of human blood memory Tfh cells and the subsets within this compartment. We present a strategy to define these subsets based on cell surface profiles. Finally, we discuss how increased understanding of the biology of blood memory Tfh cells may contribute insight into the pathogenesis of autoimmune diseases and the mode of action of vaccines. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Sodium hydrogen exchangers contribute to arenavirus cell entry.

    Science.gov (United States)

    Iwasaki, Masaharu; Ngo, Nhi; de la Torre, Juan C

    2014-01-01

    Several arenaviruses, chiefly Lassa virus (LASV), cause hemorrhagic fever (HF) disease in humans and pose a great public health concern in the regions in which they are endemic. Moreover, evidence indicates that the worldwide-distributed prototypic arenavirus lymphocytic choriomeningitis virus (LCMV) is a neglected human pathogen of clinical significance. The limited existing armamentarium to combat human-pathogenic arenaviruses underscores the importance of developing novel antiarenaviral drugs, a task that would be facilitated by the identification and characterization of virus-host cell factor interactions that contribute to the arenavirus life cycle. A genome-wide small interfering RNA (siRNA) screen identified sodium hydrogen exchanger 3 (NHE3) as required for efficient multiplication of LCMV in HeLa cells, but the mechanisms by which NHE activity contributed to the life cycle of LCMV remain unknown. Here we show that treatment with the NHE inhibitor 5-(N-ethyl-N-isopropyl) amiloride (EIPA) resulted in a robust inhibition of LCMV multiplication in both rodent (BHK-21) and human (A549) cells. EIPA-mediated inhibition was due not to interference with virus RNA replication, gene expression, or budding but rather to a blockade of virus cell entry. EIPA also inhibited cell entry mediated by the glycoproteins of the HF arenaviruses LASV and Junin virus (JUNV). Pharmacological and genetic studies revealed that cell entry of LCMV in A549 cells depended on actin remodeling and Pak1, suggesting a macropinocytosis-like cell entry pathway. Finally, zoniporide, an NHE inhibitor being explored as a therapeutic agent to treat myocardial infarction, inhibited LCMV propagation in culture cells. Our findings indicate that targeting NHEs could be a novel strategy to combat human-pathogenic arenaviruses.

  12. Anion exchange membrane fuel cells: Current status and remaining challenges

    Science.gov (United States)

    Gottesfeld, Shimshon; Dekel, Dario R.; Page, Miles; Bae, Chulsung; Yan, Yushan; Zelenay, Piotr; Kim, Yu Seung

    2018-01-01

    The anion exchange membrane fuel cell (AEMFC) is an attractive alternative to acidic proton exchange membrane fuel cells, which to date have required platinum-based catalysts, as well as acid-tolerant stack hardware. The AEMFC could use non-platinum-group metal catalysts and less expensive metal hardware thanks to the high pH of the electrolyte. Over the last decade, substantial progress has been made in improving the performance and durability of the AEMFC through the development of new materials and the optimization of system design and operation conditions. In this perspective article, we describe the current status of AEMFCs as having reached beginning of life performance very close to that of PEMFCs when using ultra-low loadings of Pt, while advancing towards operation on non-platinum-group metal catalysts alone. In the latter sections, we identify the remaining technical challenges, which require further research and development, focusing on the materials and operational factors that critically impact AEMFC performance and/or durability. These perspectives may provide useful insights for the development of next-generation of AEMFCs.

  13. Reactivation System for Proton-Exchange Membrane Fuel-Cells

    Directory of Open Access Journals (Sweden)

    Roberto Giral

    2012-07-01

    Full Text Available In recent years, Proton-Exchange Membrane Fuel Cells (PEMFCs have been the focus of very intensive researches. Manufacturers of these alternative power sources propose a rejuvenation sequence after the FC has been operating at high power for a certain period of time. These rejuvenation methods could be not appropriate for the reactivation of the FC when it has been out of operation for a long period of time or after it has been repaired. Since the developed reactivation system monitors temperature, current, and the cell voltages of the stack, it could be also useful for the diagnostic and repairing processes. The limited number of published contributions suggests that systems developing reactivation techniques are an open research field. In this paper, an automated system for reactivating PEMFCs and results of experimental testing are presented.

  14. Exercise, training and red blood cell turnover.

    Science.gov (United States)

    Smith, J A

    1995-01-01

    Endurance training can lead to what has been termed 'sports anaemia'. Although under normal conditions, red blood cells (RBCs) have a lifespan of about 120 days, the rate of aging may increase during intensive training. However, RBC deficiency is rare in athletes, and sports anaemia is probably due to an expanded plasma volume. Cycling, running and swimming have been shown to cause RBC damage. While most investigators measure indices of haemolysis (for example, plasma haemoglobin or haptoglobin), RBC removal is normally an extravascular process that does not involve haemolysis. Attention is now turning to cellular indices (such as antioxidant depletion, or protein or lipid damage) that may be more indicative of exercise-induced damage. RBCs are vulnerable to oxidative damage because of their continuous exposure to oxygen and their high concentrations of polyunsaturated fatty acids and haem iron. As oxidative stress may be proportional to oxygen uptake, it is not surprising that antioxidants in muscle, liver and RBCs can be depleted during exercise. Oxidative damage to RBCs can also perturb ionic homeostasis and facilitate cellular dehydration. These changes impair RBC deformability which can, in turn, impede the passage of RBCs through the microcirculation. This may lead to hypoxia in working muscle during single episodes of exercise and possibly an increased rate of RBC destruction with long term exercise. Providing RBC destruction does not exceed the rate of RBC production, no detrimental effect to athletic performance should occur. An increased rate of RBC turnover may be advantageous because young cells are more efficient in transporting oxygen. Because most techniques examine the RBC population as a whole, more sophisticated methods which analyse cells individually are required to determine the mechanisms involved in exercise-induced damage of RBCs.

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

    DEFF Research Database (Denmark)

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

    2005-01-01

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

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

    Science.gov (United States)

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

    1978-02-01

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

  17. Evaluation of Hematological Parameters in Partial Exchange and Packed Cell Transfusion in Treatment of Severe Anemia in Pregnancy

    Directory of Open Access Journals (Sweden)

    Sudha Salhan

    2012-01-01

    Full Text Available Objectives. Anemia is a major public health problem throughout the world which assumes prominence in pregnant mothers. Patients with severe anemia continue to present themselves at term or in labor. This study was conducted to compare the improvements in hematological parameters of patients receiving partial exchange blood transfusion and transfusion of packed cells without exchange. Methods. One hundred and twenty-five severely anemic antenatal mothers were admitted from outpatient service. Partial exchange transfusion was given to sixty-six patients while fifty-nine received transfusion of packed cells with frusemide cover. Results. The two groups were comparable in terms of age, height, weight, religion, diet, education, occupation of self and husband, and income. Hemoglobin level in Group 1 was comparatively less than Group 2 at prelevel (5.2±1.5 versus 6.6±2.3, P=0.001 and postlevel (7.2±1.5 versus 8.6±1.8, P=0.001, respectively, but there was no significant difference between the two modes of transfusion (2.09±1.6 versus 2.01±1.5, P=0.78. Conclusion. The study produced an equally significant improvement in hematological parameters in partial exchange and packed cell transfusion. Platelet counts were significantly less in partial exchange as compared with packed cell transfusion.

  18. The treatment of neurodegenerative disorders using umbilical cord blood and menstrual blood-derived stem cells.

    Science.gov (United States)

    Sanberg, Paul R; Eve, David J; Willing, Alison E; Garbuzova-Davis, Svitlana; Tan, Jun; Sanberg, Cyndy D; Allickson, Julie G; Cruz, L Eduardo; Borlongan, Cesar V

    2011-01-01

    Stem cell transplantation is a potentially important means of treatment for a number of disorders. Two different stem cell populations of interest are mononuclear umbilical cord blood cells and menstrual blood-derived stem cells. These cells are relatively easy to obtain, appear to be pluripotent, and are immunologically immature. These cells, particularly umbilical cord blood cells, have been studied as either single or multiple injections in a number of animal models of neurodegenerative disorders with some degree of success, including stroke, Alzheimer's disease, amyotrophic lateral sclerosis, and Sanfilippo syndrome type B. Evidence of anti-inflammatory effects and secretion of specific cytokines and growth factors that promote cell survival, rather than cell replacement, have been detected in both transplanted cells.

  19. Advanced proton-exchange materials for energy efficient fuel cells.

    Energy Technology Data Exchange (ETDEWEB)

    Fujimoto, Cy H.; Grest, Gary Stephen; Hickner, Michael A.; Cornelius, Christopher James; Staiger, Chad Lynn; Hibbs, Michael R.

    2005-12-01

    The ''Advanced Proton-Exchange Materials for Energy Efficient Fuel Cells'' Laboratory Directed Research and Development (LDRD) project began in October 2002 and ended in September 2005. This LDRD was funded by the Energy Efficiency and Renewable Energy strategic business unit. The purpose of this LDRD was to initiate the fundamental research necessary for the development of a novel proton-exchange membranes (PEM) to overcome the material and performance limitations of the ''state of the art'' Nafion that is used in both hydrogen and methanol fuel cells. An atomistic modeling effort was added to this LDRD in order to establish a frame work between predicted morphology and observed PEM morphology in order to relate it to fuel cell performance. Significant progress was made in the area of PEM material design, development, and demonstration during this LDRD. A fundamental understanding involving the role of the structure of the PEM material as a function of sulfonic acid content, polymer topology, chemical composition, molecular weight, and electrode electrolyte ink development was demonstrated during this LDRD. PEM materials based upon random and block polyimides, polybenzimidazoles, and polyphenylenes were created and evaluated for improvements in proton conductivity, reduced swelling, reduced O{sub 2} and H{sub 2} permeability, and increased thermal stability. Results from this work reveal that the family of polyphenylenes potentially solves several technical challenges associated with obtaining a high temperature PEM membrane. Fuel cell relevant properties such as high proton conductivity (>120 mS/cm), good thermal stability, and mechanical robustness were demonstrated during this LDRD. This report summarizes the technical accomplishments and results of this LDRD.

  20. Red blood cell transfusion in neurosurgery.

    Science.gov (United States)

    Linsler, Stefan; Ketter, Ralf; Eichler, Hermann; Schwerdtfeger, Karsten; Steudel, Wolf-Ingo; Oertel, Joachim

    2012-07-01

    The necessity of red blood cell (RBC) transfusions in neurosurgical procedures is under debate. Although detailed recommendations exist for many other surgical disciplines, there are very limited data on the probability of transfusions during neurosurgical procedures. Three-thousand and twenty-six consecutive adult patients undergoing neurosurgical procedures at Saarland University Hospital from December 2006 to June 2008 were retrospectively analyzed for administration of RBCs. The patients were grouped into 11 main diagnostic categories for analysis. The transfusion probability and cross-match to transfusion ratio (C/T ratio) were calculated. Overall, the transfusion probability for neurosurgical procedures was 1.7 % (52/3,026). The probability was 6.5 % for acute subdural hematoma (7/108), 6.2 % for spinal tumors (5/80), 4.6 % for intracerebral hemorrhage (ICH, 4/98), 2.8 % for abscess (3/108), 2.4 % for traumatic brain injury (4/162), 2.3 % for cerebral ischemia (1/44), 1.9 % for subarachnoid hemorrhage (SAH) /aneurysms (4/206), 1.4 % for brain tumors (10/718), 0.8 % for hydrocephalus (2/196), 0.4 % for degenerative diseases of the spine (5/1290), including 3.6 % (3/82) for posterior lumbar interbody fusion (PLIF) and 0 % for epidural hematoma (0/15). The transfusion probabilities for clipping and coiling of SAH were 2.9 % (2/68) and 1.7 % (2/120) respectively. The probability of blood transfusion during neurosurgical procedures is well below the 10 % level which is generally defined as the limit for preoperative appropriation of RBCs. Patients with spinal tumors, acute subdural hematomas or ICH, i.e., patients undergoing large decompressive procedures of bone or soft tissue, had a higher probability of transfusion.

  1. Modelling and validation of Proton exchange membrane fuel cell (PEMFC)

    Science.gov (United States)

    Mohiuddin, A. K. M.; Basran, N.; Khan, A. A.

    2018-01-01

    This paper is the outcome of a small scale fuel cell project. Fuel cell is an electrochemical device that converts energy from chemical reaction to electrical work. Proton Exchange Membrane Fuel Cell (PEMFC) is one of the different types of fuel cell, which is more efficient, having low operational temperature and fast start up capability results in high energy density. In this study, a mathematical model of 1.2 W PEMFC is developed and simulated using MATLAB software. This model describes the PEMFC behaviour under steady-state condition. This mathematical modeling of PEMFC determines the polarization curve, power generated, and the efficiency of the fuel cell. Simulation results were validated by comparing with experimental results obtained from the test of a single PEMFC with a 3 V motor. The performance of experimental PEMFC is little lower compared to simulated PEMFC, however both results were found in good agreement. Experiments on hydrogen flow rate also been conducted to obtain the amount of hydrogen consumed to produce electrical work on PEMFC.

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

    Science.gov (United States)

    Acharya, Vasundhara; Kumar, Preetham

    2018-03-01

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

  3. Preparation of Highly Sulfonated Ultra-Thin Proton-Exchange Polymer Membranes for Proton Exchange Membrane Fuel Cells

    Science.gov (United States)

    Jiang, Zhongqing; Meng, Yuedong; Jiang, Zhong-Jie; Shi, Yicai

    Sulfonated ultra-thin proton-exchange polymer membrane carrying pyridine groups was made from a plasma polymerization of styrene, 2-vinylpyridine, and trifluoromethanesulfonic acid by after-glow capacitively coupled discharge technique. Pyridine groups tethered to the polymer backbone acts as a medium through the basic nitrogen for transfer of protons between the sulfonic acid groups of proton exchange membrane. It shows that the method using present technology could effectively depress the degradation of monomers during the plasma polymerization. Spectroscopic analyses reveal that the obtained membranes are highly functionalized with proton exchange groups and have higher proton conductivity. Thus, the membranes are expected to be used in direct methanol fuel cells.

  4. Cost effectiveness of cord blood versus bone marrow and peripheral blood stem cells

    Directory of Open Access Journals (Sweden)

    Thomas Bart

    2010-10-01

    Full Text Available Thomas BartSwiss Blood Stem Cells, Bern, SwitzerlandAbstract: Umbilical cord blood (CB has become, since its first successful use more than two decades ago, an increasingly important source of blood stem cells. In this light, an overview of current usage of CB in the field of unrelated hematopoietic blood stem cell transplantation (HSCT is given. The three main sources of hematopoietic stem cells: bone marrow (BM, peripheral blood stem cells (PBSC, and cord blood (CB are compared as regards their current quantitative usage in HSCT. A cost analysis of the named three hematopoietic blood stem cell (HSC sources, taking into account various factors, is undertaken. The health economical comparison shows significant differences between CB on the one side, and BM and PBSC on the other. The consequences for the public health side and propositions for a possible health care policy, especially regarding future resource allocation towards the different choices for HSCT products, are discussed. An outlook on the possible future usage of BM, PBSC, and CB and its implications on health systems, donor registries, and CB banks is given.Keywords: health economy, cord blood, hematopoietic stem cell transplantation

  5. Bystander apoptosis in human cells mediated by irradiated blood plasma

    Energy Technology Data Exchange (ETDEWEB)

    Vinnikov, Volodymyr, E-mail: vlad.vinnikov@mail.ru [Grigoriev Institute for Medical Radiology of the National Academy of Medical Science of Ukraine (Ukraine); Lloyd, David; Finnon, Paul [Centre for Radiation, Chemical and Environmental Hazards of the Health Protection Agency of the United Kingdom (United Kingdom)

    2012-03-01

    Following exposure to high doses of ionizing radiation, due to an accident or during radiotherapy, bystander signalling poses a potential hazard to unirradiated cells and tissues. This process can be mediated by factors circulating in blood plasma. Thus, we assessed the ability of plasma taken from in vitro irradiated human blood to produce a direct cytotoxic effect, by inducing apoptosis in primary human peripheral blood mononuclear cells (PBM), which mainly comprised G{sub 0}-stage lymphocytes. Plasma was collected from healthy donors' blood irradiated in vitro to 0-40 Gy acute {gamma}-rays. Reporter PBM were separated from unirradiated blood with Histopaque and held in medium with the test plasma for 24 h at 37 Degree-Sign C. Additionally, plasma from in vitro irradiated and unirradiated blood was tested against PBM collected from blood given 4 Gy. Apoptosis in reporter PBM was measured by the Annexin V test using flow cytometry. Plasma collected from unirradiated and irradiated blood did not produce any apoptotic response above the control level in unirradiated reporter PBM. Surprisingly, plasma from irradiated blood caused a dose-dependent reduction of apoptosis in irradiated reporter PBM. The yields of radiation-induced cell death in irradiated reporter PBM (after subtracting the respective values in unirradiated reporter PBM) were 22.2 {+-} 1.8% in plasma-free cultures, 21.6 {+-} 1.1% in cultures treated with plasma from unirradiated blood, 20.2 {+-} 1.4% in cultures with plasma from blood given 2-4 Gy and 16.7 {+-} 3.2% in cultures with plasma from blood given 6-10 Gy. These results suggested that irradiated blood plasma did not cause a radiation-induced bystander cell-killing effect. Instead, a reduction of apoptosis in irradiated reporter cells cultured with irradiated blood plasma has implications concerning oncogenic risk from mutated cells surviving after high dose in vivo irradiation (e.g. radiotherapy) and requires further study.

  6. Bystander apoptosis in human cells mediated by irradiated blood plasma

    International Nuclear Information System (INIS)

    Vinnikov, Volodymyr; Lloyd, David; Finnon, Paul

    2012-01-01

    Following exposure to high doses of ionizing radiation, due to an accident or during radiotherapy, bystander signalling poses a potential hazard to unirradiated cells and tissues. This process can be mediated by factors circulating in blood plasma. Thus, we assessed the ability of plasma taken from in vitro irradiated human blood to produce a direct cytotoxic effect, by inducing apoptosis in primary human peripheral blood mononuclear cells (PBM), which mainly comprised G 0 -stage lymphocytes. Plasma was collected from healthy donors’ blood irradiated in vitro to 0–40 Gy acute γ-rays. Reporter PBM were separated from unirradiated blood with Histopaque and held in medium with the test plasma for 24 h at 37 °C. Additionally, plasma from in vitro irradiated and unirradiated blood was tested against PBM collected from blood given 4 Gy. Apoptosis in reporter PBM was measured by the Annexin V test using flow cytometry. Plasma collected from unirradiated and irradiated blood did not produce any apoptotic response above the control level in unirradiated reporter PBM. Surprisingly, plasma from irradiated blood caused a dose-dependent reduction of apoptosis in irradiated reporter PBM. The yields of radiation-induced cell death in irradiated reporter PBM (after subtracting the respective values in unirradiated reporter PBM) were 22.2 ± 1.8% in plasma-free cultures, 21.6 ± 1.1% in cultures treated with plasma from unirradiated blood, 20.2 ± 1.4% in cultures with plasma from blood given 2–4 Gy and 16.7 ± 3.2% in cultures with plasma from blood given 6–10 Gy. These results suggested that irradiated blood plasma did not cause a radiation-induced bystander cell-killing effect. Instead, a reduction of apoptosis in irradiated reporter cells cultured with irradiated blood plasma has implications concerning oncogenic risk from mutated cells surviving after high dose in vivo irradiation (e.g. radiotherapy) and requires further study.

  7. Red blood cell alloimmunization in pregnancy.

    Science.gov (United States)

    Moise, Kenneth J

    2005-07-01

    Red blood cell (RBC) alloimmunization in pregnancy continues to occur despite the widespread use of both antenatal and postpartum Rhesus immune globulin (RhIG), due mainly to inadvertent omissions in administration as well as antenatal sensitization prior to RhIG given at 28 weeks' gestation. Additional instances are attributable to the lack of immune globulins to other RBC antigens. Evaluation of the alloimmunized pregnancy begins with the maternal titer. Once a critical value [32 for anti-Rh(D) and other irregular antibodies; 8 for anti-K and -k] is reached, fetal surveillance using serial Doppler ultrasound measurements of the peak velocity in the fetal middle cerebral artery (MCA) is standard. In the case of a heterozygous paternal phenotype, amniocentesis can be performed to detect the antigen-negative fetus that requires no further evaluation. MCA velocities greater than 1.5 multiples of the median necessitate cordocentesis, and if fetal anemia is detected, intrauterine transfusion therapy is initiated. A perinatal survival of greater than 85% with normal neurologic outcome is now expected. Future therapies will target specific immune manipulations in the pregnant patient.

  8. Signaling pathways regulating red blood cell aggregation.

    Science.gov (United States)

    Muravyov, Alexei; Tikhomirova, Irina

    2014-01-01

    The exposure of red blood cells (RBC) to some hormones (epinephrine, insulin and glucagon) and agonists of α- and β-adrenergic receptors (phenylephrine, clonidine and isoproterenol) may modify RBC aggregation (RBCA). Prostaglandin E1 (PGE1) significantly decreased RBCA, and PGE2 had a similar but lesser effect. Adenylyl cyclase (AC) stimulator forskolin added to RBC suspension, caused a decrease of RBCA. More marked lowering of RBCA occurred after RBC treatment by dB-cAMP. Phosphodiesterase (PDE) inhibitors markedly reduced RBCA. Ca2+ influx stimulated by A23187 was accompanied by an increase of RBCA. The blocking of Ca2+ entry into the RBC by verapamil or the chelation of Ca2+ by EGTA led to a significant RBCA decrease. Lesser changes of aggregation were found after RBC incubation with protein kinase C stimulator phorbol 12-myristate 13-acetate (PMA). A significant inhibitory effect of tyrosine protein kinase (TPK) activator cisplatin on RBCA was revealed, while selective TPK inhibitor, lavendustin, eliminated the above mentioned effect. Taken together, the data demonstrate that changes in RBCA are connected with activation of different intracellular signaling pathways. We suggest that alterations in RBCA are mainly associated with the crosstalk between the adenylyl cyclase-cAMP system and Ca2+ control mechanisms.

  9. Multifactorial aspects of antibody-mediated blood cell destruction

    NARCIS (Netherlands)

    Kapur, R.

    2014-01-01

    The research described in this thesis focuses on diseases of antibody-mediated blood cell destruction via FcγRs on phagocytes, in particular regarding platelets in fetal or neonatal alloimmune thrombocytopenia (FNAIT) and red blood cells (RBC) in hemolytic disease of the fetus and newborn (HDFN).

  10. Magnetophoretic separation of blood cells at the microscale

    International Nuclear Information System (INIS)

    Furlani, E P

    2007-01-01

    We present a method and model for the direct and continuous separation of red and white blood cells in plasma. The method is implemented at the microscale using a microfluidic system that consists of an array of integrated soft-magnetic elements embedded adjacent to a microfluidic channel. The microsystem is passive and is activated via application of a bias field that magnetizes the elements. Once magnetized, the elements produce a nonuniform magnetic field distribution in the microchannel, which gives rise to a force on blood cells as they pass through the microsystem. In whole blood, white blood cells behave as diamagnetic microparticles while red blood cells exhibit diamagnetic or paramagnetic behaviour depending on the oxygenation of their haemoglobin. We develop a mathematical model for predicting the motion of blood cells in the microsystem that takes into account the dominant magnetic, fluidic and buoyant forces on the cells. We use the model to study red/white blood cell transport, and our analysis indicates that the microsystem is capable of rapid and efficient red/white blood cell separation

  11. Multiple loci are associated with white blood cell phenotypes

    NARCIS (Netherlands)

    M.A. Nalls (Michael); D. Couper (David); T. Tanaka (Toshiko); F.J.A. van Rooij (Frank); M-H. Chen (Ming-Huei); A.V. Smith (Albert Vernon); D. Toniolo (Daniela); N.A. Zakai (Neil); Q. Yang (Qiong Fang); A. Greinacher (Andreas); A.R. Wood (Andrew); M. Garcia (Melissa); P. Gasparini (Paolo); Y. Liu (YongMei); T. Lumley (Thomas); A.R. Folsom (Aaron); A.P. Reiner (Alex); C. Gieger (Christian); V. Lagou (Vasiliki); J.F. Felix (Janine); H. Völzke (Henry); N.A. Gouskova (Natalia); A. Biffi (Alessandro); A. Döring (Angela); U. Völker (Uwe); S. Chong (Sean); K.L. Wiggins (Kerri); A. Rendon (Augusto); A. Dehghan (Abbas); M. Moore (Matt); K.D. Taylor (Kent); J.G. Wilson (James); G. Lettre (Guillaume); A. Hofman (Albert); J.C. Bis (Joshua); N. Pirastu (Nicola); C.S. Fox (Caroline); C. Meisinger (Christa); J.G. Sambrook (Jennifer); S. Arepalli (Sampath); M. Nauck (Matthias); H. Prokisch (Holger); J. Stephens (Jonathan); N.L. Glazer (Nicole); L.A. Cupples (Adrienne); Y. Okada (Yukinori); A. Takahashi (Atsushi); Y. Kamatani (Yoichiro); K. Matsuda (Koichi); T. Tsunoda (Tatsuhiko); M. Kubo (Michiaki); Y. Nakamura (Yusuke); K. Yamamoto (Kazuhiko); M. Stumvoll (Michael); A. Tönjes (Anke); I. Prokopenko (Inga); T. Illig (Thomas); K.V. Patel (Kushang); S.F. Garner (Stephen); B. Kuhnel (Brigitte); M. Mangino (Massimo); B.A. Oostra (Ben); S.L. Thein; J. Coresh (Josef); H.E. Wichmann (Heinz Erich); S. Menzel (Stephan); J. Lin; G. Pistis (Giorgio); A.G. Uitterlinden (André); T.D. Spector (Timothy); A. Teumer (Alexander); G. Eiriksdottir (Gudny); V. Gudnason (Vilmundur); S. Bandinelli (Stefania); T.M. Frayling (Timothy); A. Chakravarti (Aravinda); P. Tikka-Kleemola (Päivi); D. Melzer (David); W.H. Ouwehand (Willem); D. Levy (Daniel); E.A. Boerwinkle (Eric); A. Singleton (Andrew); D.G. Hernandez (Dena); D.L. Longo (Dan); N. Soranzo (Nicole); J.C.M. Witteman (Jacqueline); B.M. Psaty (Bruce); L. Ferrucci (Luigi); T.B. Harris (Tamara); C.J. O'Donnell (Christopher); S.K. Ganesh (Santhi)

    2011-01-01

    textabstractWhite blood cell (WBC) count is a common clinical measure from complete blood count assays, and it varies widely among healthy individuals. Total WBC count and its constituent subtypes have been shown to be moderately heritable, with the heritability estimates varying across cell types.

  12. HCV RNA in peripheral blood mononuclear cells (PBMCs) as a ...

    African Journals Online (AJOL)

    Background: Hepatitis C virus (HCV) has been found to infect peripheral blood mononuclear cells (PBMCs), using them as a reservoir, which might contribute to the development of resistance to treatment. Objectives: To study hepatitis virus C (HCV) RNA in peripheral blood mononuclear cells (PBMCs) of patients with ...

  13. HCV RNA in peripheral blood mononuclear cells (PBMCs) as a ...

    African Journals Online (AJOL)

    Abdel Fatah Fahmy Hanno

    2013-06-27

    Jun 27, 2013 ... Abstract Background: Hepatitis C virus (HCV) has been found to infect peripheral blood mono- nuclear cells (PBMCs), using them as a reservoir, which might contribute to the development of resistance to treatment. Objectives: To study hepatitis virus C (HCV) RNA in peripheral blood mononuclear cells.

  14. Effect of Induced Pluripotent Stem Cell Technology in Blood Banking

    Science.gov (United States)

    Focosi, Daniele

    2016-01-01

    Summary Population aging has imposed cost-effective alternatives to blood donations. Artificial blood is still at the preliminary stages of development, and the need for viable cells seems unsurmountable. Because large numbers of viable cells must be promptly available for clinical use, stem cell technologies, expansion, and banking represent ideal tools to ensure a regular supply. Provided key donors can be identified, induced pluripotent stem cell (iPSC) technology could pave the way to a new era in transfusion medicine, just as it is already doing in many other fields of medicine. The present review summarizes the current state of research on iPSC technology in the field of blood banking, highlighting hurdles, and promises. Significance The aging population in Western countries is causing a progressive reduction of blood donors and a constant increase of blood recipients. Because blood is the main therapeutic option to treat acute hemorrhage, cost-effective alternatives to blood donations are being actively investigated. The enormous replication capability of induced pluripotent stem cells and their promising results in many other fields of medicine could be an apt solution to produce the large numbers of viable cells required in transfusion and usher in a new era in transfusion medicine. The present report describes the potentiality, technological hurdles, and promises of induced pluripotent stem cells to generate red blood cells by redifferentiation. PMID:26819256

  15. A microfluidic chip for direct and rapid trapping of white blood cells from whole blood

    Science.gov (United States)

    Chen, Jingdong; Chen, Di; Yuan, Tao; Xie, Yao; Chen, Xiang

    2013-01-01

    Blood analysis plays a major role in medical and science applications and white blood cells (WBCs) are an important target of analysis. We proposed an integrated microfluidic chip for direct and rapid trapping WBCs from whole blood. The microfluidic chip consists of two basic functional units: a winding channel to mix and arrays of two-layer trapping structures to trap WBCs. Red blood cells (RBCs) were eliminated through moving the winding channel and then WBCs were trapped by the arrays of trapping structures. We fabricated the PDMS (polydimethylsiloxane) chip using soft lithography and determined the critical flow velocities of tartrazine and brilliant blue water mixing and whole blood and red blood cell lysis buffer mixing in the winding channel. They are 0.25 μl/min and 0.05 μl/min, respectively. The critical flow velocity of the whole blood and red blood cell lysis buffer is lower due to larger volume of the RBCs and higher kinematic viscosity of the whole blood. The time taken for complete lysis of whole blood was about 85 s under the flow velocity 0.05 μl/min. The RBCs were lysed completely by mixing and the WBCs were trapped by the trapping structures. The chip trapped about 2.0 × 103 from 3.3 × 103 WBCs. PMID:24404026

  16. Plerixafor enables the safe, rapid, efficient mobilization of haematopoietic stem cells in sickle cell disease patients after exchange transfusion.

    Science.gov (United States)

    Lagresle-Peyrou, Chantal; Lefrère, François; Magrin, Elisa; Ribeil, Jean-Antoine; Romano, Oriana; Weber, Leslie; Magnani, Alessandra; Sadek, Hanem; Plantier, Clémence; Gabrion, Aurélie; Ternaux, Brigitte; Félix, Tristan; Couzin, Chloé; Stanislas, Aurélie; Tréluyer, Jean-Marc; Lamhaut, Lionel; Joseph, Laure; Delville, Marianne; Miccio, Annarita; André-Schmutz, Isabelle; Cavazzana, Marina

    2018-02-22

    Sickle cell disease is characterized by chronic anaemia and vaso-occlusive crises, which eventually lead to multi-organ damage and premature death. Haematopoietic stem cell transplantation is the only curative treatment but it is limited by toxicity and poor availability of HLA-compatible donors. A gene therapy approach based on the autologous transplantation of lentiviral-corrected haematopoietic stem and progenitor cells was shown to be efficacious in one patient. However, alterations of the bone marrow environment and the red blood cells' properties hamper the harvesting and immunoselection of patient stem cells from bone marrow. The use of Filgrastim to mobilize large numbers of haematopoietic stem and progenitor cells (HSPC) in the circulation has been associated with severe adverse events in sickle cell patients. Thus, broader application of the gene therapy approach requires the development of alternative mobilization methods. We set up a Phase I/II clinical trial whose primary objective was to assess the safety of a single injection of Plerixafor in sickle cell patients under RBC exchanges to decrease Haemoglobin S level below 30%. The secondary objective was to measure the efficiency of HSPC mobilization and isolation. No adverse events were observed. Large numbers of CD34+ cells were mobilized extremely quickly. Importantly, the mobilized cells contained high numbers of haematopoietic stem cells, expressed high levels of stemness genes, and engrafted very efficiently in immunodeficient mice. Thus, Plerixafor can be safely used to mobilize haematopoietic stem cells in sickle cell patients; this finding opens up new avenues for treatment approaches based on gene addition and genome editing. Copyright © 2018, Ferrata Storti Foundation.

  17. Analysis performance of proton exchange membrane fuel cell (PEMFC)

    Science.gov (United States)

    Mubin, A. N. A.; Bahrom, M. H.; Azri, M.; Ibrahim, Z.; Rahim, N. A.; Raihan, S. R. S.

    2017-06-01

    Recently, the proton exchange membrane fuel cell (PEMFC) has gained much attention to the technology of renewable energy due to its mechanically ideal and zero emission power source. PEMFC performance reflects from the surroundings such as temperature and pressure. This paper presents an analysis of the performance of the PEMFC by developing the mathematical thermodynamic modelling using Matlab/Simulink. Apart from that, the differential equation of the thermodynamic model of the PEMFC is used to explain the contribution of heat to the performance of the output voltage of the PEMFC. On the other hand, the partial pressure equation of the hydrogen is included in the PEMFC mathematical modeling to study the PEMFC voltage behaviour related to the input variable input hydrogen pressure. The efficiency of the model is 33.8% which calculated by applying the energy conversion device equations on the thermal efficiency. PEMFC’s voltage output performance is increased by increasing the hydrogen input pressure and temperature.

  18. Durable Catalysts for High Temperature Proton Exchange Membrane Fuel Cells

    DEFF Research Database (Denmark)

    significant attention in recent years because of its potential advantages such as high CO tolerance, easy cooling, better heat utilization and possible integration with fuel processing units. However, the high temperature obviously aggravates the carbon corrosion and catalyst degradation. Based on thermally......Durability of proton exchange membrane fuel cells (PEMFCs) is recognized as one of the most important issues to be addressed before the commercialization. The failure mechanisms are not well understood, however, degradation of carbon supported noble metal catalysts is identified as a major failure...... corrosion, in turn, triggers the agglomeration of platinum particles resulting in reduction of the active surface area and catalytic activity. This is a major mechanism of the catalyst degradation and a key challenge to the PEMFC long-term durability. High temperature PEMFC, on the other hand, has attached...

  19. Spatial proton exchange membrane fuel cell performance under bromomethane poisoning

    Science.gov (United States)

    Reshetenko, Tatyana V.; Artyushkova, Kateryna; St-Pierre, Jean

    2017-02-01

    The poisoning effects of 5 ppm CH3Br in the air on the spatial performance of a proton exchange membrane fuel cell (PEMFC) were studied using a segmented cell system. The presence of CH3Br caused performance loss from 0.650 to 0.335 V at 1 A cm-2 accompanied by local current density redistribution. The observed behavior was explained by possible bromomethane hydrolysis with the formation of Br-. Bromide and bromomethane negatively affected the oxygen reduction efficiency over a wide range of potentials because of their adsorption on Pt, which was confirmed by XPS. Moreover, the PEMFC exposure to CH3Br led to a decrease in the anode and cathode electrochemical surface area (∼52-57%) due to the growth of Pt particles through agglomeration and Ostwald ripening. The PEMFC did not restore its performance after stopping bromomethane introduction to the air stream. However, the H2/N2 purge of the anode/cathode and CV scans almost completely recovered the cell performance. The observed final loss of ∼50 mV was due to an increased activation overpotential. PEMFC exposure to CH3Br should be limited to concentrations much less than 5 ppm due to serious performance loss and lack of self-recovery.

  20. Water Soluble Polymers as Proton Exchange Membranes for Fuel Cells

    Directory of Open Access Journals (Sweden)

    Bing-Joe Hwang

    2012-03-01

    Full Text Available The relentless increase in the demand for useable power from energy-hungry economies continues to drive energy-material related research. Fuel cells, as a future potential power source that provide clean-at-the-point-of-use power offer many advantages such as high efficiency, high energy density, quiet operation, and environmental friendliness. Critical to the operation of the fuel cell is the proton exchange membrane (polymer electrolyte membrane responsible for internal proton transport from the anode to the cathode. PEMs have the following requirements: high protonic conductivity, low electronic conductivity, impermeability to fuel gas or liquid, good mechanical toughness in both the dry and hydrated states, and high oxidative and hydrolytic stability in the actual fuel cell environment. Water soluble polymers represent an immensely diverse class of polymers. In this comprehensive review the initial focus is on those members of this group that have attracted publication interest, principally: chitosan, poly (ethylene glycol, poly (vinyl alcohol, poly (vinylpyrrolidone, poly (2-acrylamido-2-methyl-1-propanesulfonic acid and poly (styrene sulfonic acid. The paper then considers in detail the relationship of structure to functionality in the context of polymer blends and polymer based networks together with the effects of membrane crosslinking on IPN and semi IPN architectures. This is followed by a review of pore-filling and other impregnation approaches. Throughout the paper detailed numerical results are given for comparison to today’s state-of-the-art Nafion® based materials.

  1. Exercise-induced blood lactate increase does not change red blood cell deformability in cyclists.

    Directory of Open Access Journals (Sweden)

    Michael J Simmonds

    Full Text Available BACKGROUND: The effect of exercise-induced lactate production on red blood cell deformability and other blood rheological changes is controversial, given heavy-exercise induces biochemical processes (e.g., oxidative stress known to perturb haemorheology. The aim of the present study was to examine the haemorheological response to a short-duration cycling protocol designed to increase blood lactate concentration, but of duration insufficient to induce significant oxidative stress. METHODS: Male cyclists and triathletes (n = 6; 27±7 yr; body mass index: 23.7±3.0 kg/m²; peak oxygen uptake 4.02±0.51 L/min performed unloaded (0 W, moderate-intensity, and heavy-intensity cycling. Blood was sampled at rest and during the final minute of each cycling bout. Blood chemistry, blood viscosity, red blood cell aggregation and red blood cell deformability were measured. RESULTS: Blood lactate concentration increased significantly during heavy-intensity cycling, when compared with all other conditions. Methaemoglobin fraction did not change during any exercise bout when compared with rest. Blood viscosity at native haematocrit increased during heavy-intensity cycling at higher-shear rates when compared with rest, unloaded and moderate-intensity cycling. Heavy-intensity exercise increased the amplitude of red blood cell aggregation in native haematocrit samples when compared with all other conditions. Red blood cell deformability was not changed by exercise. CONCLUSION: Acute exercise perturbs haemorheology in an intensity dose-response fashion; however, many of the haemorheological effects appear to be secondary to haemoconcentration, rather than increased lactate concentration.

  2. Red blood cell vesiculation in hereditary hemolytic anemia

    Directory of Open Access Journals (Sweden)

    Amr eAlaarg

    2013-12-01

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

  3. Red blood cell vesiculation in hereditary hemolytic anemia

    Science.gov (United States)

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

    2013-01-01

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

  4. DEVELOPMENT OF NOVEL ELECTROCATALYSTS FOR PROTON EXCHANGE MEMBRANE FUEL CELLS

    Energy Technology Data Exchange (ETDEWEB)

    Shamsuddin Ilias

    2001-07-06

    Proton Exchange Membrane Fuel Cell (PEMFC) is one of the most promising power sources for space and electric vehicle applications. Platinum (Pt) catalyst is used for both fuel and air electrodes in PEMFCs. The carbon monoxide (CO) contamination of H{sub 2} greatly affects electrocatalysts used at the anode of PEMFCs and decrease the cell performance. This irreversible poisoning of the anode can happen even in CO concentrations as low as few ppm, and therefore, require expensive scrubbing of the H{sub 2}-fuel to reduce the contaminant concentration to acceptable level. In order to commercialize this environmentally sound source of energy/power system, development of suitable CO-tolerant catalyst is needed. In this work, we have synthesized several novel electrocatalysts (Pt/C, Pt/Ru/C Pt/Mo/C, Pt/Ir and Pt/Ru/Mo) for PEMFCs. These catalysts have been tested for CO tolerance in the H{sub 2}/air fuel cell. The concentration of CO in the H{sub 2} fuel varied from 10 ppm to 100 ppm. The performance of the electrodes was evaluated by determining the cell potential against current density. The effect of temperature, catalyst compositions, and electrode film preparation methods on the performance of PEM fuel cell has also been studied. It was found that at 70 C and 3.5 atm pressure at the cathode, Pt-alloy catalysts (10 wt % Pt/Ru/C, 20 wt % Pt/Mo/C) were more CO-tolerant than 20 wt % Pt catalyst alone. It was also observed that spraying method is better for the preparation of electrode film than the brushing technique. Some of these results are summarized in this report.

  5. Physiology and pathophysiology of Na+/H+ exchange and Na+-K+-2Cl- cotransport in the heart, brain, and blood

    DEFF Research Database (Denmark)

    Pedersen, S. F.; O´Donnell, M. E.; Anderson, S. E.

    2006-01-01

    Maintenance of a stable cell volume and intracellular pH is critical for normal cell function. Arguably, two of the most important ion transporters involved in these processes are the Na+/H+ exchanger isoform 1 (NHE1) and Na+-K+-2Cl- cotransporter isoform 1 (NKCC1). Both NHE1 and NKCC1....... The aim is to provide a comprehensive overview of the mechanisms and consequences of stress-induced stimulation of these transporters with focus on the heart, brain, and blood. The physiological stressors reviewed are metabolic/exercise stress, osmotic stress, and mechanical stress, conditions in which...... are stimulated by cell shrinkage and by numerous other stimuli, including a wide range of hormones and growth factors, and for NHE1, intracellular acidification. Both transporters can be important regulators of cell volume, yet their activity also, directly or indirectly, affects the intracellular concentrations...

  6. Measuring density and compressibility of white blood cells and prostate cancer cells by microchannel acoustophoresis

    DEFF Research Database (Denmark)

    Barnkob, Rune; Augustsson, Per; Magnusson, Cecilia

    2011-01-01

    to determine the density and compressibility of individual cells enables the prediction and alteration of the separation outcome for a given cell mixture. We apply the method on white blood cells (WBCs) and DU145 prostate cancer cells (DUCs) aiming to improve isolation of circulating tumor cells from blood......, an emerging tool in the monitoring and characterizing of metastatic cancer....

  7. Exchange transfusion of least incompatible blood for severe hemolytic disease of the newborn due to anti-Rh17.

    Science.gov (United States)

    Li, Bi-juan; Jiang, Yuan-jun; Yuan, Fen; Ye, Hong-xing

    2010-02-01

    HDN attributed to the rare Rh variants has become more and more significant caused by anti-D, but the compatible blood is usually very difficult to obtain when exchange transfusion is required. We treated a 10-hour neonate of O, D + C + c - E - e+ blood group with severe HDN due to anti-Rh17 with least incompatible blood typed O, D + C - c + E + e-. The neonatal hemolysis was relieved obviously and bilirubin was reduced gradually after exchange transfusion. The infant was discharged in good health 13 days after birth with 135.0 g/L, 28.0 micromol/L and 10.7 micromol/L of Hb, total bilirubin and direct bilirubin, respectively. No sequelae were observed in a three-year follow-up. The result suggesting that the least incompatible blood is an alternative choice for exchange transfusion in severe HDN due to anti-Rh17 in case that Rh17 antigen-negative blood is unavailable.

  8. NMR water-proton spin-lattice relaxation time of human red blood cells and red blood cell suspensions

    International Nuclear Information System (INIS)

    Sullivan, S.G.; Rosenthal, J.S.; Winston, A.; Stern, A.

    1988-01-01

    NMR water-proton spin-lattice relaxation times were studied as probes of water structure in human red blood cells and red blood cell suspensions. Normal saline had a relaxation time of about 3000 ms while packed red blood cells had a relaxation time of about 500 ms. The relaxation time of a red blood cell suspension at 50% hematocrit was about 750 ms showing that surface charges and polar groups of the red cell membrane effectively structure extracellular water. Incubation of red cells in hypotonic saline increases relaxation time whereas hypertonic saline decreases relaxation time. Relaxation times varied independently of mean corpuscular volume and mean corpuscular hemoglobin concentration in a sample population. Studies with lysates and resealed membrane ghosts show that hemoglobin is very effective in lowering water-proton relaxation time whereas resealed membrane ghosts in the absence of hemoglobin are less effective than intact red cells. 9 refs.; 3 figs.; 1 table

  9. Cyclooxygenase-2-dependent prostacyclin formation and blood pressure homeostasis: targeted exchange of cyclooxygenase isoforms in mice

    DEFF Research Database (Denmark)

    Yu, Ying; Stubbe, Jane; Ibrahim, Salam

    2010-01-01

    pressure. OBJECTIVE: To elucidate the role of COX-2 in blood pressure homeostasis using COX-1>COX-2 mice, in which the COX-1 expression is controlled by COX-2 regulatory elements. METHODS AND RESULTS: COX-1>COX-2 mice developed systolic hypertension relative to wild types (WTs) on a high-salt diet (HSD...... and again the increase in formation of PGI(2) observed in WTs was suppressed in cells derived from both mutants. Intramedullary infusion of the PGI(2) receptor agonist increased urine volume and sodium excretion in mice. CONCLUSIONS: These studies suggest that dysregulated expression of the COX-2 dependent...

  10. Blood

    Science.gov (United States)

    ... production of red blood cells, including: Iron deficiency anemia. Iron deficiency anemia is the most common type of anemia and ... inflammatory bowel disease are especially likely to have iron deficiency anemia. Anemia due to chronic disease. People with chronic ...

  11. Prevalence of irregular red blood cell antibodies among healthy blood donors in Delhi population.

    Science.gov (United States)

    Garg, Neeraj; Sharma, Tanya; Singh, Bharat

    2014-06-01

    To evaluate the prevalence of the anti-red blood cell antibodies among healthy blood donors. Antibody screening of all voluntary blood donor serum was performed as routine immunohematological procedure. Positive sera were further investigated to identify the specificity of irregular erythrocyte antibody by commercially available red cell panel (ID-Dia Panel, Diamed-ID Microtyping System). A total of 47,450 donors were screened for the presence of irregular erythrocyte antibodies. A total of forty-six donors showed presence of alloantibodies in their serum (46/47,450%, 0.09%), yielding a prevalence of 0.09%. Most frequent alloantibodies identified were of MNS blood group system. The results showed statistically a higher prevalence of RBC alloantibodies in females than in males. Screening for presence of alloantibodies in donor blood is important to provide compatible blood products and to avoid transfusion reactions. Copyright © 2014 Elsevier Ltd. All rights reserved.

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

    Science.gov (United States)

    Hitt, Darren L.; Lowe, Mary L.

    1996-11-01

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

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

    DEFF Research Database (Denmark)

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

    2007-01-01

    Enzymatic removal of blood group ABO antigens to develop universal red blood cells (RBCs) was a pioneering vision originally proposed more than 25 years ago. Although the feasibility of this approach was demonstrated in clinical trials for group B RBCs, a major obstacle in translating this techno......Enzymatic removal of blood group ABO antigens to develop universal red blood cells (RBCs) was a pioneering vision originally proposed more than 25 years ago. Although the feasibility of this approach was demonstrated in clinical trials for group B RBCs, a major obstacle in translating...

  14. Nucleated red blood cells in infants of mothers with asthma.

    Science.gov (United States)

    Littner, Yoav; Mandel, Dror; Sheffer-Mimouni, Galit; Mimouni, Francis B; Deutsch, Varda; Dollberg, Shaul

    2003-02-01

    The purpose of this study was to evaluate whether the absolute nucleated red blood cell and lymphocyte count is elevated in term, appropriate-for-gestational-age infants born to women with asthma. We compared absolute nucleated red blood cell counts taken during the first 12 hours of life in two groups of term, vaginally delivered, appropriate-for-gestational-age infants; one group was born to mothers with active asthma during pregnancy (n = 28 infants), and the other group was born to control mothers (n = 29 infants). Asthma severity was classified according to the National Asthma Education and Prevention Program. We excluded infants of women with diabetes mellitus, hypertension, alcohol, and tobacco or drug abuse and infants with fetal heart rate abnormalities, hemolysis, blood loss, or chromosomal anomalies. There were no differences between groups in birth weight, gestational age, maternal age, gravidity, parity, maternal analgesia during labor, 1- and 5-minute Apgar scores, and infant sex. The hematocrit level, red blood cell count, absolute nucleated red blood cell count, and corrected leukocyte and lymphocyte counts were significantly higher in the asthma group than in the control group. The platelet count was not significantly different between groups. The absolute nucleated red blood cell count correlated significantly with the asthma severity score (r (2) = 28%, P cell count with the presence of asthma and its severity (P mothers with asthma have increased circulating absolute nucleated red blood cell and lymphocyte counts compared with control infants.

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

    DEFF Research Database (Denmark)

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

    2012-01-01

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

  16. Separation of cancer cells from white blood cells by pinched flow fractionation

    DEFF Research Database (Denmark)

    Jensen, Marie Pødenphant; Ashley, Neil; Koprowska, Kamila

    2015-01-01

    In this paper, the microfluidic size-separation technique pinched flow fractionation (PFF) is used to separate cancer cells from white blood cells (WBCs). The cells are separated at efficiencies above 90% for both cell types. Circulating tumor cells (CTCs) are found in the blood of cancer patients...... and can form new tumors. CTCs are rare cells in blood, but they are important for the understanding of metastasis. There is therefore a high interest in developing a method for the enrichment of CTCs from blood samples, which also enables further analysis of the separated cells. The separation...

  17. Numerical modeling transport phenomena in proton exchange membrane fuel cells

    Science.gov (United States)

    Suh, DongMyung

    To study the coupled phenomena occurring in proton exchange membrane fuel cells, a two-phase, one-dimensional, non-isothermal model is developed in the chapter 1. The model includes water phase change, proton transport in the membrane and electro-osmotic effect. The thinnest, but most complex layer in the membrane electrode assembly, catalyst layer, is considered an interfacial boundary between the gas diffusion layer and the membrane. Mass and heat transfer and electro-chemical reaction through the catalyst layer are formulated into equations, which are applied to boundary conditions for the gas diffusion layer and the membrane. Detail accounts of the boundary equations and the numerical solving procedure used in this work are given. The polarization curve is calculated at different oxygen pressures and compared with the experimental results. When the operating condition is changed along the polarization curve, the change of physicochemical variables in the membrane electrode assembly is studied. In particular, the over-potential diagram presents the usage of the electrochemical energy at each layer of the membrane electrode assembly. Humidity in supplying gases is one of the most important factors to consider for improving the performance of PEMFE. Both high and low humidity conditions can result in a deteriorating cell performance. The effect of humidity on the cell performance is studied in the chapter 2. First, a numerical model based on computational fluid dynamics is developed. Second, the cell performances are simulated, when the relative humidity is changed from 0% to 100% in the anode and the cathode channel. The simulation results show how humidity in the reactant gases affects the water content distribution in the membrane, the over-potential at the catalyst layers and eventually the cell performance. In particular, the rapid enhancement in the cell performance caused by self-hydrating membrane is captured by the simulation. Fully humidifying either H2

  18. Protonic conductors for proton exchange membrane fuel cells: An overview

    Directory of Open Access Journals (Sweden)

    Jurado Ramon Jose

    2002-01-01

    Full Text Available At present, Nation, which is a perfluorinated polymer, is one of the few materials that deliver the set of chemical and mechanical properties required to perform as a good electrolyte in proton exchange membrane fuel cells (PEMFCs. However, Nation presents some disadvantages, such as limiting the operational temperature of the fuel system (So°C, because of its inability to retain water at higher temperatures and also suffers chemical crossover. In addition to these restrictions, Nation membranes are very expensive. Reducing costs and using environmentally friendly materials are good reasons to make a research effort in this field in order to achieve similar or even better fuel-cell performances. Glass materials of the ternary system SiO2-ZrO2-P2O5, hybrid materials based on Nation, and nanopore ceramic membranes based on SiO2 TiO2, Al2O3, etc. are considered at present, as promising candidates to replace Nation as the electrolyte in PEMFCs. These types of materials are generally prepared by sol-gel processes in order to tailor their channel-porous structure and pore size. In this communication, the possible candidates in the near future as electrolytes (including other polymers different than Nation in PEMFCs are briefly reviewed. Their preparation methods, their electrical transport properties and conduction mechanisms are considered. The advantages and disadvantages of these materials with respect to Nation are also discussed.

  19. White blood cell count - series (image)

    Science.gov (United States)

    ... the hand. The puncture site is cleaned with antiseptic, and a tourniquet (an elastic band) or blood ... or young child: The area is cleansed with antiseptic and punctured with a sharp needle or a ...

  20. Kinetics of thallium exchange in cultured rat myocardial cells.

    Science.gov (United States)

    McCall, D; Zimmer, L J; Katz, A M

    1985-03-01

    The kinetics of thallium exchange in cultured rat myocardial cells were studied and compared to those of potassium in the same tissue. Studies were carried out using low concentrations (10 nM to 5 microM) of thallium-204, approximating those likely to be encountered during clinical myocardial scintigraphy. Both thallium uptake and release could be described by a single exponential with a half-time of exchange which was approximately half that of potassium and which was largely independent of extracellular thallium concentration. Some 60% of thallium uptake occurred via an "active" or ouabain-inhibitable mechanism which, in the absence of extracellular potassium, could be activated by low concentrations (10 nM to 5 microM) of thallium. The apparent Km for thallium on this active transport mechanism was 2-7 microM. Increasing extracellular potassium from 0-10 mM caused significant, concentration-dependent decreases in both the total and the active component of the thallium influx. Similarly nonradioactive thallium (0.10 microM to 0.10 mM) caused a concentration-dependent decrease in active potassium influx. Analysis of these results by both Lineweaver-Burk plots and Dixon plots confirmed competitive inhibition, potassium on thallium influx and vice versa, for the active component of the fluxes, and noncompetitive in the remainder. These findings indicate that active transport accounts for the greater portion of the influx of thallium and potassium, and that this active transport occurs via a common mechanism.(ABSTRACT TRUNCATED AT 250 WORDS)

  1. Natural killer cells for immunotherapy – Advantages of cell lines over blood NK cells

    Directory of Open Access Journals (Sweden)

    Hans eKlingemann

    2016-03-01

    Full Text Available Natural killer cells are potent cytotoxic effector cells for cancer therapy and potentially for severe viral infections. However, there are technical challenges to obtain sufficient numbers of functionally active NK cells form a patient’s blood since they represent only 10% of the lymphocytes. Especially, cancer patients are known to have dysfunctional NK cells. The alternative is to obtain cells from a healthy donor, which requires depletion of the allogeneic T-cells. Establishing cell lines from donor blood NK cells have not been successful, in contrast to blood NK cells obtained from patients with a clonal NK cell lymphoma. Those cells can be expanded in culture in the presence of IL-2. However, except for the NK-92 cell line none of the other six known cell lines has consistent and reproducibly high anti-tumor cytotoxicity, nor can they be easily genetically manipulated to recognize specific tumor antigens or to augment monoclonal antibody activity through ADCC. NK-92 is also the only cell line product that has been widely given to patients with advanced cancer with demonstrated efficiency and minimal side effects.

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

    Science.gov (United States)

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

    2013-11-01

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

  3. Assessment of DNA Damage in Peripheral Blood Lymphocytes of Radiation Workers at Al-Tuwaitha Site by Using the Sister Chromatid Exchange and the Comet Assay

    International Nuclear Information System (INIS)

    Ali, A.K.; Muttar, A.J.; Khayon, S.K.; Haider, Y.L.; Ali, H.F.; Abdullah, A.K.

    2015-01-01

    The sister chromatid exchange was performed on peripheral blood lymphocytes obtained from 40 individuals of workers occupationally exposed to low ionizing radiation doses in Al-Tuwaitha site due to decommissioning to radioactive contamination then compared with 40 control individuals living in Baghdad. SCEs were scored in metaphase chromosomes were identified by fluorescent plus Giemsa staining (Figure 2).The mean frequencies of SCEs per cell differed significantly (p≺0 0.05) between individuals of radiation workers and control, being 7.78 0.45 SCE/cells and 6.28 0.22 SCE/cells , respectively. However SCE frequency was statistically significant (P≺0 0.05) among radiation workers as compared to control individuals.

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

    Science.gov (United States)

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

    2016-08-01

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

  5. Color contrast of red blood cells on solid substrate

    Science.gov (United States)

    Paiziev, Adkham A.

    2013-02-01

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

  6. Methemoglobin reductase activity in intact fish red blood cells

    DEFF Research Database (Denmark)

    Jensen, Frank B; Nielsen, Karsten

    2018-01-01

    Red blood cells (RBCs) possess methemoglobin reductase activity that counters the ongoing oxidation of hemoglobin (Hb) to methemoglobin (metHb), which in circulating blood is caused by Hb autoxidation or reactions with nitrite. We describe an assay for determining metHb reductase activity in intact...

  7. Frequency and specificity of red blood cell alloantibodies among ...

    African Journals Online (AJOL)

    Background: Blood transfusion usually results in production of alloantibody against one or more foreign red blood cell antigens which may complicate subsequent transfusions. The probability of alloimmunization depends on number and frequency of transfusion, antigen immunogenicity, recipient immune response and ...

  8. RISK OF RED BLOOD CELL ALLOIMMUNISATION IN RWANDA ...

    African Journals Online (AJOL)

    2013-04-04

    Apr 4, 2013 ... EDTA (ethylenediaminetetraacetic acid) vacutainer test tubes. Within 12 hours, samples underwent centrifugation at 3000 rpm lasting three minutes. Plasma samples were extracted and kept at -30ºC and red blood cell samples at 2 to 6ºC in the Regional. Blood Centre of Rwamagana in Eastern Province.

  9. Risk of red blood cell alloimmunisation in Rwanda: Assessment of ...

    African Journals Online (AJOL)

    Background: Screening of alloantibodies in patients is not yet done in district hospitals of Rwanda. The practice is to transfuse ABO/D compatible blood following an immediate spin crossmatch (IS-XM) or indirect antiglobulin test crossmatch (IAT-XM). Objectives: To assess the risk of red blood cell (RBC) alloimmunisation ...

  10. Certain Red Blood Cell Indices of Maternal and Umbilical Cord ...

    African Journals Online (AJOL)

    Uche

    blood samples were obtained immediately after delivery of the baby. The umbilical blood samples were collected from the umbilical cord of the baby at the end of the second stage of labour. The haemoglobin (Hb) concentration and packed cell volume (PCV) were determined using standard procedures. The mean ...

  11. The Rh complex exports ammonium from human red blood cells

    NARCIS (Netherlands)

    Hemker, Mirte B.; Cheroutre, Goedele; van Zwieten, Rob; Maaskant-van Wijk, Petra A.; Roos, Dirk; Loos, Johannes A.; van der Schoot, C. Ellen; von dem Borne, Albert E. G. Kr

    2003-01-01

    The Rh blood group system represents a major immunodominant protein complex on red blood cells (RBC). Recently, the Rh homologues RhAG and RhCG were shown to promote ammonium ion transport in yeast. In this study, we showed that also in RBC the human Rh complex functions as an exporter of ammonium

  12. DNA damage in peripheral blood mononuclear cells and neutrophils ...

    African Journals Online (AJOL)

    This study was designed to investigate the apoptotic process in peripheral blood mononuclear cells (PBMC) and polymorphonuclear neutrophil leukocytes (PMN) in dairy cattle during the transition period. Blood samples were collected from 4 dairy cattle at 3 weeks before the expected parturition (wk -3), parturition (wk 0) ...

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

    DEFF Research Database (Denmark)

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

    2015-01-01

    OBJECTIVE: To compare the benefit and harm of restrictive versus liberal transfusion strategies to guide red blood cell transfusions. DESIGN: Systematic review with meta-analyses and trial sequential analyses of randomised clinical trials. DATA SOURCES: Cochrane central register of controlled...... differences with 95% confidence intervals. RESULTS: 31 trials totalling 9813 randomised patients were included. The proportion of patients receiving red blood cells (relative risk 0.54, 95% confidence interval 0.47 to 0.63, 8923 patients, 24 trials) and the number of red blood cell units transfused (mean...... were associated with a reduction in the number of red blood cell units transfused and number of patients being transfused, but mortality, overall morbidity, and myocardial infarction seemed to be unaltered. Restrictive transfusion strategies are safe in most clinical settings. Liberal transfusion...

  14. Safety and radiation risks in the labelling of blood cells

    International Nuclear Information System (INIS)

    Gonzalez, B.M.

    1994-01-01

    Risk in the management of radioactive material and biological exposition to infectious agents. Protocols and normative to observe GOOD RADIOPHARMACY Practices. Main infectious agents that may be transmitted during preparation of a blood cell radiopharmaceutical. Problems of contamination

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

    African Journals Online (AJOL)

    SERVER

    2008-04-03

    n = 30). ... test in red blood cells and lymphocytes can be used as an indicator of toxic effects in determined target populations (Berces et al., 1993). Since DNA repair .... tion in the increase of breaks in DNA strands by.

  16. Enthalpy analysis and Heat Exchanger Sizing of an Air-cooled Proton Exchange Membrane Fuel Cell System

    DEFF Research Database (Denmark)

    Gao, Xin; Berning, Torsten; Kær, Søren Knudsen

    Proton exchange membrane fuel cells (PEMFC’s) are becoming increasingly popular for uninterrupted power supply especially in remote areas. In the case of telecom back-up operations, PEMFC systems are often placed in areas of extreme climates, e.g. in Norway or Canada where the temperatures drop...... or an ordinary heat exchanger can fulfill the heat recovery demand. Despite the fact that the air enters the stack at a cold temperature, even the forefront of the stack is at a much elevated and desired stack temperature with the help of supplying an acceptable amount of power to an electric stack heater. So...

  17. Detection of melanoma cells suspended in mononuclear cells and blood plasma using photoacoustic generation

    Science.gov (United States)

    Spradling, Emily M.; Viator, John A.

    2009-02-01

    Melanoma is the deadliest form of skin cancer. Although the initial malignant cells are removed, it is impossible to determine whether or not the cancer has metastasized until a secondary tumor forms that is large enough to detect with conventional imaging. Photoacoustic detection of circulating melanoma cells in the bloodstream has shown promise for early detection of metastasis that may aid in treatment of this aggressive cancer. When blood is irradiated with energy from an Nd:YAG laser at 532 nm, photoacoustic signals are created and melanoma cells can be differentiated from the surrounding cells based on waveforms produced by an oscilloscope. Before this can be used as a diagnostic technique, however, we needed to investigate several parameters. Specifically, the current technique involves the in vitro separation of blood through centrifugation to isolate and test only the white blood cell layer. Using this method, we have detected a single cultured melanoma cell among a suspension of white blood cells. However, the process could be made simpler if the plasma layer were used for detection instead of the white blood cell layer. This layer is easier to obtain after blood separation, the optical difference between plasma and melanoma cells is more pronounced in this layer than in the white blood cell layer, and the possibility that any stray red blood cells could distort the results is eliminated. Using the photoacoustic apparatus, we detected no melanoma cells within the plasma of whole blood samples spiked with cultured melanoma cells.

  18. PROLYTIC ION EXCHANGES PRODUCED IN HUMAN RED CELLS BY METHANOL, ETHANOL, GUAIACOL, AND RESORCINOL

    Science.gov (United States)

    Ponder, Eric

    1947-01-01

    When the washed red cells of heparinized human blood are exposed at 4°C. to methanol, ethanol, guaiacol, or resorcinol in hypolytic concentrations in isotonic NaCl, the prolytic loss of K at the end of 20 hours varies from about 25 per cent of the initial K content of the cells in the case of 3.1 M methanol to about 55 per cent of the initial K in the case of 0.04 M resorcinol. As in the case of the prolytic losses observed with other lysins, the K loss is rapid at first and then slows down so that what appears to be a new steady state is reached logarithmically. The K lost from the cells during the period of the prolytic loss is replaced by an approximately equivalent amount of Na, derived from the isotonic NaCl in which the cells are suspended. The Na which enters can be replaced by K by washing the cells in isotonic KCl, and this K can again be replaced by Na by washing the cells in isotonic NaCl. The remainder of the cell K., i.e. the K which was not lost during the period of the prolytic loss, is retained in the cell unaffected by these washing procedures. The capacity of red cells for undergoing disk-sphere transformations is scarcely affected by their having been exposed to hypolytic concentrations of methanol, ethanol, guaiacol, or resorcinol in isotonic NaCl, and their resistance to osmotic hemolysis and to lysis by saponin and digitonin is altered only in minor respects even when as much as 50 per cent of the cell K has been exchanged for Na. Some restriction to the movement of K between the cell and its environment is apparently modified irreversibly when the cell is exposed to hypolytic concentrations of lysins, and the modification is such that only a fraction of the cell K is affected, the fraction being a function of the lysin concentration, the duration of its action, and other factors. A modification of some part of the cell structure and of the properties dependent on its integrity is probably involved: K may be lost more readily from some cells

  19. Novel automated blood separations validate whole cell biomarkers.

    Directory of Open Access Journals (Sweden)

    Douglas E Burger

    Full Text Available Progress in clinical trials in infectious disease, autoimmunity, and cancer is stymied by a dearth of successful whole cell biomarkers for peripheral blood lymphocytes (PBLs. Successful biomarkers could help to track drug effects at early time points in clinical trials to prevent costly trial failures late in development. One major obstacle is the inaccuracy of Ficoll density centrifugation, the decades-old method of separating PBLs from the abundant red blood cells (RBCs of fresh blood samples.To replace the Ficoll method, we developed and studied a novel blood-based magnetic separation method. The magnetic method strikingly surpassed Ficoll in viability, purity and yield of PBLs. To reduce labor, we developed an automated platform and compared two magnet configurations for cell separations. These more accurate and labor-saving magnet configurations allowed the lymphocytes to be tested in bioassays for rare antigen-specific T cells. The automated method succeeded at identifying 79% of patients with the rare PBLs of interest as compared with Ficoll's uniform failure. We validated improved upfront blood processing and show accurate detection of rare antigen-specific lymphocytes.Improving, automating and standardizing lymphocyte detections from whole blood may facilitate development of new cell-based biomarkers for human diseases. Improved upfront blood processes may lead to broad improvements in monitoring early trial outcome measurements in human clinical trials.

  20. Novel automated blood separations validate whole cell biomarkers.

    Science.gov (United States)

    Burger, Douglas E; Wang, Limei; Ban, Liqin; Okubo, Yoshiaki; Kühtreiber, Willem M; Leichliter, Ashley K; Faustman, Denise L

    2011-01-01

    Progress in clinical trials in infectious disease, autoimmunity, and cancer is stymied by a dearth of successful whole cell biomarkers for peripheral blood lymphocytes (PBLs). Successful biomarkers could help to track drug effects at early time points in clinical trials to prevent costly trial failures late in development. One major obstacle is the inaccuracy of Ficoll density centrifugation, the decades-old method of separating PBLs from the abundant red blood cells (RBCs) of fresh blood samples. To replace the Ficoll method, we developed and studied a novel blood-based magnetic separation method. The magnetic method strikingly surpassed Ficoll in viability, purity and yield of PBLs. To reduce labor, we developed an automated platform and compared two magnet configurations for cell separations. These more accurate and labor-saving magnet configurations allowed the lymphocytes to be tested in bioassays for rare antigen-specific T cells. The automated method succeeded at identifying 79% of patients with the rare PBLs of interest as compared with Ficoll's uniform failure. We validated improved upfront blood processing and show accurate detection of rare antigen-specific lymphocytes. Improving, automating and standardizing lymphocyte detections from whole blood may facilitate development of new cell-based biomarkers for human diseases. Improved upfront blood processes may lead to broad improvements in monitoring early trial outcome measurements in human clinical trials.

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

    DEFF Research Database (Denmark)

    Damgaard, Christian; Magnussen, Karin; Enevold, Christian

    2015-01-01

    the oral cavity, and to determine the distribution of bacteria revealed in plasma and in the red blood cell (RBC)-fraction. DESIGN: Cross-sectional study. Blood were separated into plasma and RBC-suspensions, which were incubated anaerobically or aerobically for 7 days on trypticase soy blood agar (TSA......), self-reported medically healthy. RESULTS: Bacterial growth was observed on plates inoculated with plasma or RBCs from 62% of the blood donations. Growth was evident in 21 (35%) of 60 RBC-fractions and in 32 (53%) of 60 plasma-fractions versus 8 of 60 negative controls (p = 0.005 and p = 2.6x10......OBJECTIVES: Infection remains a leading cause of post-transfusion mortality and morbidity. Bacterial contamination is, however, detected in less than 0.1% of blood units tested. The aim of the study was to identify viable bacteria in standard blood-pack units, with particular focus on bacteria from...

  2. Mechanisms Linking Red Blood Cell Disorders and Cardiovascular Diseases

    OpenAIRE

    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 dise...

  3. Computational fluid dynamics modeling of proton exchange membrane fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    UM,SUKKEE; WANG,C.Y.; CHEN,KEN S.

    2000-02-11

    A transient, multi-dimensional model has been developed to simulate proton exchange membrane (PEM) fuel cells. The model accounts simultaneously for electrochemical kinetics, current distribution, hydrodynamics and multi-component transport. A single set of conservation equations valid for flow channels, gas-diffusion electrodes, catalyst layers and the membrane region are developed and numerically solved using a finite-volume-based computational fluid dynamics (CFD) technique. The numerical model is validated against published experimental data with good agreement. Subsequently, the model is applied to explore hydrogen dilution effects in the anode feed. The predicted polarization cubes under hydrogen dilution conditions are found to be in qualitative agreement with recent experiments reported in the literature. The detailed two-dimensional electrochemical and flow/transport simulations further reveal that in the presence of hydrogen dilution in the fuel stream, hydrogen is depleted at the reaction surface resulting in substantial kinetic polarization and hence a lower current density that is limited by hydrogen transport from the fuel stream to the reaction site.

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

    NARCIS (Netherlands)

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

    1999-01-01

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

  5. Influence of microwaves and electron beam on red blood cells

    International Nuclear Information System (INIS)

    Hategan, A.; Martin, D.; Popescu, A.; Butan, C.

    1999-01-01

    The effects of 6 MeV electron beam and of 2.45 GHz microwaves on the osmotic fragility of frozen cryoprotected human red blood cell membranes are presented. The changes in the properties of the red blood cell membranes were estimated by measuring the radiation induced haemoglobin release from the red blood cells (haemolysis) and the osmotic fragility of the membranes, determined by postirradiation induced osmotic stress. We obtained no haemolysis induced by accelerated electrons in the range 0 - 400 Gy, whereas the microwave irradiated red blood cells showed in the ranges 1 - 2 min and 400 - 500 W values of very small haemolysis, down to 50 % from the control. The osmotic stress experiments indicated a significant increase in the osmotic fragility for 200 - 400 Gy electron doses, whereas the 100 Gy irradiated sample showed a haemolysis down to 35 % from the control. Similarly, the microwave irradiated red blood cells showed values down to 60% from the control for (1 min, 850 W). Both radiations induced at definite parameters values of very small haemolysis, suggesting a stabilisation of the membranes and an increase in the osmotic resistance. Our preliminary results on simultaneous irradiation of the frozen red blood cells seem to indicate a significant contribution of the microwaves in haemolysis evolution, while the successive irradiation procedure did not allow so far a clear interpretation, further studies being necessary to elucidate the physico-chemical mechanisms induced. (authors)

  6. Induction and identification of rabbit peripheral blood derived dendritic cells

    Science.gov (United States)

    Zhou, Jing; Yang, FuYuan; Chen, WenLi

    2012-03-01

    Purpose: To study a method of the induction of dendritic cells (DCs) from rabbit peripheral blood. Methods: Peripheral blood cells were removed from rabbit, filtered through nylon mesh. Peripheral blood mononuclear cells (PBMC) were isolated from the blood cells by Ficoll-Hypaque centrifugation (density of 1.077g/cm3).To obtain DCs, PBMC were cultured in RPMI1640 medium containing 10% fetal calf serum, 50U/mL penicillin and streptomycin, referred to subsequently as complete medium, at 37°C in 5% CO2 atmosphere for 4 hours. Nonadherent cells were aspirated, adherent cells were continued incubated in complete medium, supplemented with granulocyte/macrophage colony-stimulating factor (GM-CSF, 50ng/ml),and interleukin 4 (IL-4, 50ng/ml) for 9 days. Fluorescein labeled antibodies(anti-CD14, anti-HLA-DR, anti-CD86) were used to sign cells cultured for 3,6,9 days respectively, Then flow cytometry was performed. Results: Ratio of anti-HLA-DR and anti-CD86 labeled cells increased with induction time extension, in contrast with anti-CD14. Conclusion: Dendritic cells can be effectively induced by the method of this experiment, cell maturation status increased with induction time extension.

  7. Theoretical study of inspiratory flow waveforms during mechanical ventilation on pulmonary blood flow and gas exchange.

    Science.gov (United States)

    Niranjan, S C; Bidani, A; Ghorbel, F; Zwischenberger, J B; Clark, J W

    1999-08-01

    A lumped two-compartment mathematical model of respiratory mechanics incorporating gas exchange and pulmonary circulation is utilized to analyze the effects of square, descending and ascending inspiratory flow waveforms during mechanical ventilation. The effects on alveolar volume variation, alveolar pressure, airway pressure, gas exchange rate, and expired gas species concentration are evaluated. Advantages in ventilation employing a certain inspiratory flow profile are offset by corresponding reduction in perfusion rates, leading to marginal effects on net gas exchange rates. The descending profile provides better CO2 exchange, whereas the ascending profile is more advantageous for O2 exchange. Regional disparities in airway/lung properties create maldistribution of ventilation and a concomitant inequality in regional alveolar gas composition and gas exchange rates. When minute ventilation is maintained constant, for identical time constant disparities, inequalities in compliance yield pronounced effects on net gas exchange rates at low frequencies, whereas the adverse effects of inequalities in resistance are more pronounced at higher frequencies. Reduction in expiratory air flow (via increased airway resistance) reduces the magnitude of upstroke slope of capnogram and oxigram time courses without significantly affecting end-tidal expired gas compositions, whereas alterations in mechanical factors that result in increased gas exchanges rates yield increases in CO2 and decreases in O2 end-tidal composition values. The model provides a template for assessing the dynamics of cardiopulmonary interactions during mechanical ventilation by combining concurrent descriptions of ventilation, capillary perfusion, and gas exchange. Copyright 1999 Academic Press.

  8. Alveolar gas exchange and tissue oxygenation during incremental treadmill exercise, and their associations with blood O2 carrying capacity

    Directory of Open Access Journals (Sweden)

    Antti-Pekka E. Rissanen

    2012-07-01

    Full Text Available The magnitude and timing of oxygenation responses in highly active leg muscle, less active arm muscle, and cerebral tissue, have not been studied with simultaneous alveolar gas exchange measurement during incremental treadmill exercise. Nor is it known, if blood O2 carrying capacity affects the tissue-specific oxygenation responses. Thus, we investigated alveolar gas exchange and tissue (m. vastus lateralis, m. biceps brachii, cerebral cortex oxygenation during incremental treadmill exercise until volitional fatigue, and their associations with blood O2 carrying capacity in 22 healthy men. Alveolar gas exchange was measured, and near-infrared spectroscopy (NIRS was used to monitor relative concentration changes in oxy- (Δ[O2Hb], deoxy- (Δ[HHb] and total hemoglobin (Δ[tHb], and tissue saturation index (TSI. NIRS inflection points (NIP, reflecting changes in tissue-specific oxygenation, were determined and their coincidence with ventilatory thresholds (anaerobic threshold (AT, respiratory compensation point (RC; V-slope method was examined. Blood O2 carrying capacity (total hemoglobin mass (tHb-mass was determined with the CO-rebreathing method. In all tissues, NIPs coincided with AT, whereas RC was followed by NIPs. High tHb-mass associated with leg muscle deoxygenation at peak exercise (e.g., Δ[HHb] from baseline walking to peak exercise vs. tHb-mass: r = 0.64, p < 0.01, but not with arm muscle- or cerebral deoxygenation. In conclusion, regional tissue oxygenation was characterized by inflection points, and tissue oxygenation in relation to alveolar gas exchange during incremental treadmill exercise resembled previous findings made during incremental cycling. It was also found out, that O2 delivery to less active m. biceps brachii may be limited by an accelerated increase in ventilation at high running intensities. In addition, high capacity for blood O2 carrying was associated with a high level of m. vastus lateralis deoxygenation at peak

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

    NARCIS (Netherlands)

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

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

  10. Red blood cell phenotype prevalence in blood donors who self-identify as Hispanic

    DEFF Research Database (Denmark)

    Sheppard, Chelsea A; Bolen, Nicole L; Eades, Beth

    2017-01-01

    CONCLUSIONS: Molecular genotyping platforms provide a quick, high-throughput method for identifying red blood cell units for patients on extended phenotype-matching protocols, such as those with sickle cell disease or thalassemia. Most of the antigen prevalence data reported are for non-Hispanic ...

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

    Science.gov (United States)

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

    2016-03-07

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

  12. CD163 positive subsets of blood dendritic cells

    DEFF Research Database (Denmark)

    Maniecki, Maciej Bogdan; Møller, Holger Jon; Moestrup, Søren Kragh

    2006-01-01

    expression in dendritic cells (DCs) was investigated using multicolor flow cytometry in peripheral blood from 31 healthy donors and 15 HIV-1 patients in addition to umbilical cord blood from 5 newborn infants. Total RNA was isolated from MACS purified DCs and CD163 mRNA was determined with real-time reverse...... transcriptase polymerase chain reaction. The effect of glucocorticoid and phorbol ester stimulation on monocyte and dendritic cell CD163 and CD91 expression was investigated in cell culture of mononuclear cells using multicolor flow cytometry. We identified two CD163+ subsets in human blood with dendritic cell...... characteristics, CD163lo and CD163hi, together constituting a substantial fraction of DCs. Both subsets were characterized as [lin]- CD4+ ILT3+ HLA-DR+ CD11c+ by flow cytometry, and CD163 mRNA was readily detectable in MACS purified human DCs. CD163 on DCs was upregulated by glucocorticoid, and treatment...

  13. Quantitative assessment of limb blood flow using Tc-99m labeled red blood cells

    International Nuclear Information System (INIS)

    Itoh, Kazuo; Shougase, Takashi; Kawamura, Naoyuki; Tsukamoto, Eriko; Nakada, Kunihiro; Sakuma, Makoto; Furudate, Masayori

    1987-01-01

    A quantitative assessment of limb blood flow using a non-diffusible radioindicator, Tc-99m labeled red blood cells, was reported. This was an application of venous occlusion plethysmography using radionuclide which was originally proposed by M. Fukuoka et al. The peripheral blood flow (mean ± s.e.) of 30 legs in a normal control group was 1.87 ± 0.08 ml/100 ml/min. In heart diseases (46 legs), it was 1.49 ± 0.13 ml/100 ml/min. The limb blood flow between a control group and heart diseases was statistically significant (p < 0.01) in the t-test. The peripheral blood flow at rest between diseased legs and normal legs in occlusive arterial disorders was also statistically significant (p < 0.01) in a paired t-test. RAVOP was done after the completion of objective studies such as radionuclide angiography or ventriculography. Technique and calculation of a blood flow were very easy and simple. RAVOP study which was originally proposed by Fukuoka et al. was reappraised to be hopeful for quantitative measurement of limb blood flow as a non-invasive technique using Tc-99m labeled red blood cells. (author)

  14. Evaluation of hepatic hemangioma by Tc-99 m red blood cell hepatic blood pool scan

    Energy Technology Data Exchange (ETDEWEB)

    Sohn, Myung Hee [Chonbuk National University Medical School, Chonju (Korea, Republic of)

    2005-02-15

    Hemangioma is the most common benign tumor of the liver, with a prevalence estimated as high as 7%. Tc-99m red blood cell (RBC) hepatic blood pool scan with single photon emission computed tomography (SPECT) imaging is extremely useful for the confirmation or exclusion of hepatic hemangiomas. The classic finding of absent or decreased perfusion and increased blood pooling ('perfusion/blood pool mismatch') is the key diagnostic element in the diagnosis of hemangiomas. The combination of early arterial flow and delayed blood pooling ('perfusion/blood pool match') is shown uncommonly. In giant hemangioma, filling with radioactivity appears first in the periphery, with progressive central fill-in on sequential RBC blood pool scan. However, the reverse filling pattern, which begins first in the center with progressive peripheral filling, is also rarely seen. Studies with false-positive blood pooling have been reported infrequently in nonhemangiomas, including hemangiosarcoma, hepatocellular carcinoma, hepatic adenoma, and metastatic carcinomas (adenocarcinma of the colon, small cell carcinoma of the lung, neruroendocrine carcinoma). False-negative results have been also reported rarely except for small hemagniomas that are below the limits of spatial resolution of gamma camera.

  15. Drawings of Blood Cells Reveal People's Perception of Their Blood Disorder: A Pilot Study.

    Directory of Open Access Journals (Sweden)

    Steven Ramondt

    Full Text Available Sickle cell disease (SCD and thalassemia are rare but chronic blood disorders. Recent literature showed impaired quality of life (QOL in people with these blood disorders. Assessing one of the determinants of QOL (i.e. illness perceptions therefore, is an important next research area.We aimed to explore illness perceptions of people with a blood disorder with drawings in addition to the Brief Illness Perception Questionnaire (Brief IPQ. Drawings are a novel method to assess illness perceptions and the free-range answers drawings offer can add additional insight into how people perceive their illness.We conducted a cross-sectional study including 17 participants with a blood disorder. Participants' illness perceptions were assessed by the Brief IPQ and drawings. Brief IPQ scores were compared with reference groups from the literature (i.e. people with asthma or lupus erythematosus.Participants with SCD or thalassemia perceived their blood disorder as being more chronic and reported more severe symptoms than people with either asthma or lupus erythematosus. In the drawings of these participants with a blood disorder, a greater number of blood cells drawn was negatively correlated with perceived personal control (P<0.05, indicating that a greater quantity in the drawing is associated with more negative or distressing beliefs.Participants with a blood disorder perceive their disease as fairly threatening compared with people with other chronic illnesses. Drawings can add additional insight into how people perceive their illness by offering free-range answers.

  16. Evaluation of hepatic hemangioma by Tc-99 m red blood cell hepatic blood pool scan

    International Nuclear Information System (INIS)

    Sohn, Myung Hee

    2005-01-01

    Hemangioma is the most common benign tumor of the liver, with a prevalence estimated as high as 7%. Tc-99m red blood cell (RBC) hepatic blood pool scan with single photon emission computed tomography (SPECT) imaging is extremely useful for the confirmation or exclusion of hepatic hemangiomas. The classic finding of absent or decreased perfusion and increased blood pooling ('perfusion/blood pool mismatch') is the key diagnostic element in the diagnosis of hemangiomas. The combination of early arterial flow and delayed blood pooling ('perfusion/blood pool match') is shown uncommonly. In giant hemangioma, filling with radioactivity appears first in the periphery, with progressive central fill-in on sequential RBC blood pool scan. However, the reverse filling pattern, which begins first in the center with progressive peripheral filling, is also rarely seen. Studies with false-positive blood pooling have been reported infrequently in nonhemangiomas, including hemangiosarcoma, hepatocellular carcinoma, hepatic adenoma, and metastatic carcinomas (adenocarcinma of the colon, small cell carcinoma of the lung, neruroendocrine carcinoma). False-negative results have been also reported rarely except for small hemagniomas that are below the limits of spatial resolution of gamma camera

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

    Directory of Open Access Journals (Sweden)

    Jakob M A Mauritz

    2009-04-01

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

  18. Differentiation of blood T cells: Reprogramming human induced pluripotent stem cells into neuronal cells.

    Science.gov (United States)

    Tsai, Ping-Hsing; Chang, Yun-Ching; Lee, Yi-Yen; Ko, Yu-Ling; Yang, Yu-Hsuan; Lin, Chun-Fu; Chang, Yuh-Lih; Yu, Wen-Chung; Shih, Yang-Hsin; Chen, Ming-Teh

    2015-06-01

    Human induced pluripotent stem cells (iPSCs) morphologically and functionally resemble human embryonic stem cells, which presents the opportunity to use patient-specific somatic cells for disease modeling and drug screening. In order to take one step closer to clinical applications, it is important to generate iPSCs through a less invasive approach and from any accessible tissue, including peripheral blood. Meanwhile, how to differentiate blood cell-derived iPSCs into neuron-like cells is still unclear. We utilized Epstein-Barr nuclear antigen-1-based episomal vectors, a nonviral system that can reprogram somatic cells into iPSCs in both feeder-dependent and feeder-free conditions, to generate iPSCs from T cells via electroporation and then induce them into neuronal cells. We successfully isolated sufficient T cells from 20 mL peripheral blood of the donors and reprogrammed these T cells into iPSCs within 4 weeks. These iPSCs could be stably passaged to at least 50 passages, and exhibited the abilities of pluripotency and multiple-lineage differentiation. Notably, under the medium induction for 21 days, these T-cell-derived iPSCs could be differentiated into Nestin (neural progenitor marker)-, GFAP (glial cell marker)-, and MAP2 (neuron cell marker)-positive cells detected by immunofluorescence methods. We have developed a safer method to generate integration-free and nonviral human iPSCs from adult somatic cells. This induction method will be useful for the derivation of human integration-free iPSCs and will also be applicable to the generation of iPSCs-derived neuronal cells for drug screening or therapeutics in the near future. Copyright © 2015. Published by Elsevier Taiwan.

  19. Laser-photophoretic migration and fractionation of human blood cells.

    Science.gov (United States)

    Monjushiro, Hideaki; Tanahashi, Yuko; Watarai, Hitoshi

    2013-05-13

    Laser photophoretic migration behavior of human blood cells in saline solution was investigated under the irradiation of Nd:YAG laser beam (532 nm) in the absence and the presence of the flow in a fused silica capillary. Red blood cells (RBC) were migrated faster than white blood cells (WBC) and blood pellets to the direction of propagation of laser light. The observed photophoretic velocity of RBC was about 11 times faster than those of others. This was understood from the larger photophoretic efficiency of RBC than that of WBC, which was simulated based on the Mie scattering theory. Furthermore, it was found that, during the photophoretic migration, RBCs spontaneously orientated parallel to the migration direction so as to reduce the drag force. Finally, it was demonstrated that RBC and WBC were separated in a micro-channel flow system by the laser photophoresis. Copyright © 2013 Elsevier B.V. All rights reserved.

  20. White Blood Cell Counts and Malaria

    National Research Council Canada - National Science Library

    McKenzie, F. E; Prudhomme, Wendy A; Magill, Alan J; Forney, J. R; Permpanich, Barnyen; Lucas, Carmen; Gasser, Jr., Robert A; Wongsrichanalai, Chansuda

    2005-01-01

    .... In Thailand, one-sixth of the P. falciparum infected patients had WBC counts of !4000 cells/mL. Leukopenia may confound population studies that estimate parasite densities on the basis of an assumed WBC count of 8000 cells/mL...

  1. Reducing nitrogen crossover in microbial reverse-electrodialysis cells by using adjacent anion exchange membranes and anion exchange resin

    KAUST Repository

    Wallack, Maxwell J.

    2015-01-01

    Microbial reverse electrodialysis cells (MRECs) combine power generation from salinity gradient energy using reverse electrodialysis (RED), with power generation from organic matter using a microbial fuel cell. Waste heat can be used to distill ammonium bicarbonate into high (HC) and low salt concentration (LC) solutions for use in the RED stack, but nitrogen crossover into the anode chamber must be minimized to avoid ammonia loses, and foster a healthy microbial community. To reduce nitrogen crossover, an additional low concentration (LC) chamber was inserted before the anode using an additional anion exchange membrane (AEM) next to another AEM, and filled with different amounts of anion or cation ion exchange resins. Addition of the extra AEM increased the ohmic resistance of the test RED stack from 103 Ω cm2 (1 AEM) to 295 Ω cm2 (2 AEMs). However, the use of the anion exchange resin decreased the solution resistance of the LC chamber by 74% (637 Ω cm2, no resin; 166 Ω cm2 with resin). Nitrogen crossover into the anode chamber was reduced by up to 97% using 50% of the chamber filled with an anion exchange resin compared to the control (no additional chamber). The added resistance contributed by the use of the additional LC chamber could be compensated for by using additional LC and HC membrane pairs in the RED stack.

  2. Filter characteristics influencing circulating tumor cell enrichment from whole blood.

    Directory of Open Access Journals (Sweden)

    Frank A W Coumans

    Full Text Available A variety of filters assays have been described to enrich circulating tumor cells (CTC based on differences in physical characteristics of blood cells and CTC. In this study we evaluate different filter types to derive the properties of the ideal filter for CTC enrichment. Between 0.1 and 10 mL of whole blood spiked with cells from tumor cell lines were passed through silicon nitride microsieves, polymer track-etched filters and metal TEM grids with various pore sizes. The recovery and size of 9 different culture cell lines was determined and compared to the size of EpCAM+CK+CD45-DNA+ CTC from patients with metastatic breast, colorectal and prostate cancer. The 8 µm track-etched filter and the 5 µm microsieve had the best performance on MDA-231, PC3-9 and SKBR-3 cells, enriching >80% of cells from whole blood. TEM grids had poor recovery of ∼25%. Median diameter of cell lines ranged from 10.9-19.0 µm, compared to 13.1, 10.7, and 11.0 µm for breast, prostate and colorectal CTC, respectively. The 11.4 µm COLO-320 cell line had the lowest recovery of 17%. The ideal filter for CTC enrichment is constructed of a stiff, flat material, is inert to blood cells, has at least 100,000 regularly spaced 5 µm pores for 1 ml of blood with a ≤10% porosity. While cell size is an important factor in determining recovery, other factors must be involved as well. To evaluate a filtration procedure, cell lines with a median size of 11-13 µm should be used to challenge the system.

  3. Constant Power Control of a Proton Exchange Membrane Fuel Cell through Adaptive Fuzzy Sliding Mode

    OpenAIRE

    Minxiu Yan; Liping Fan

    2013-01-01

    Fuel cell is a device that converts the chemical energy from a fuel into electricity through a chemical reaction with oxygen or another oxidizing agent. The paper describes a mathematical model of proton exchange membrane fuel cells by analyzing the working mechanism of the proton exchange membrane fuel cell. Furthermore, an adaptive fuzzy sliding mode controller is designed for the constant power output of PEMFC system. Simulation results prove that adaptive fuzzy sliding mode control has be...

  4. Evaluation of a Passive Heat Exchanger Based Cooling System for Fuel Cell Applications

    Science.gov (United States)

    Colozza, Anthony J.; Burke, Kenneth A.

    2011-01-01

    Fuel cell cooling is conventionally performed with an actively controlled, dedicated coolant loop that exchanges heat with a separate external cooling loop. To simplify this system the concept of directly cooling a fuel cell utilizing a coolant loop with a regenerative heat exchanger to preheat the coolant entering the fuel cell with the coolant exiting the fuel cell was analyzed. The preheating is necessary to minimize the temperature difference across the fuel cell stack. This type of coolant system would minimize the controls needed on the coolant loop and provide a mostly passive means of cooling the fuel cell. The results indicate that an operating temperature of near or greater than 70 C is achievable with a heat exchanger effectiveness of around 90 percent. Of the heat exchanger types evaluated with the same type of fluid on the hot and cold side, a counter flow type heat exchanger would be required which has the possibility of achieving the required effectiveness. The number of heat transfer units required by the heat exchanger would be around 9 or greater. Although the analysis indicates the concept is feasible, the heat exchanger design would need to be developed and optimized for a specific fuel cell operation in order to achieve the high effectiveness value required.

  5. Shape memory of human red blood cells.

    Science.gov (United States)

    Fischer, Thomas M

    2004-05-01

    The human red cell can be deformed by external forces but returns to the biconcave resting shape after removal of the forces. If after such shape excursions the rim is always formed by the same part of the membrane, the cell is said to have a memory of its biconcave shape. If the rim can form anywhere on the membrane, the cell would have no shape memory. The shape memory was probed by an experiment called go-and-stop. Locations on the membrane were marked by spontaneously adhering latex spheres. Shape excursions were induced by shear flow. In virtually all red cells, a shape memory was found. After stop of flow and during the return of the latex spheres to the original location, the red cell shape was biconcave. The return occurred by a tank-tread motion of the membrane. The memory could not be eliminated by deforming the red cells in shear flow up to 4 h at room temperature as well as at 37 degrees C. It is suggested that 1). the characteristic time of stress relaxation is >80 min and 2). red cells in vivo also have a shape memory.

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

    DEFF Research Database (Denmark)

    Ashenden, M; Mørkeberg, Jakob Sehested

    2011-01-01

    BACKGROUND AND OBJECTIVES  Two main blood storage procedures can be used for storing red blood cells: refrigeration and freezing. Nevertheless, the efficiency of these procedures measured as the increase in haemoglobin after reinfusion compared with baseline has never been examined. The main...... objective was to examine which storage procedure yielded the largest increase in circulating haemoglobin after reinfusion compared to baseline. MATERIALS AND METHODS  Equal volumes of blood from 15 men were withdrawn and stored either frozen or refrigerated as packed red blood cells. Serial measures...... of circulating haemoglobin by carbon monoxide rebreathing provided an opportunity to monitor recovery from anaemia, as well as the net increase in circulating haemoglobin after transfusion. RESULTS  The post-thaw yield of haemoglobin in the bags was 72% after refrigerated storage compared with only 52% after...

  7. Shape Memory of Human Red Blood Cells

    OpenAIRE

    Fischer, Thomas M.

    2004-01-01

    The human red cell can be deformed by external forces but returns to the biconcave resting shape after removal of the forces. If after such shape excursions the rim is always formed by the same part of the membrane, the cell is said to have a memory of its biconcave shape. If the rim can form anywhere on the membrane, the cell would have no shape memory. The shape memory was probed by an experiment called go-and-stop. Locations on the membrane were marked by spontaneously adhering latex spher...

  8. Mechanisms of red blood cell transfusion-related immunomodulation

    NARCIS (Netherlands)

    Remy, Kenneth E.; Hall, Mark W.; Cholette, Jill; Juffermans, Nicole P.; Nicol, Kathleen; Doctor, Allan; Blumberg, Neil; Spinella, Philip C.; Norris, Philip J.; Dahmer, Mary K.; Muszynski, Jennifer A.

    2018-01-01

    Red blood cell (RBC) transfusion is common in critically ill, postsurgical, and posttrauma patients in whom both systemic inflammation and immune suppression are associated with adverse outcomes. RBC products contain a multitude of immunomodulatory mediators that interact with and alter immune cell

  9. Filter characteristics influencing circulating tumor cell enrichment from whole blood.

    NARCIS (Netherlands)

    Coumans, F.A.W.; van Dalum, Guus; Beck, Markus; Terstappen, Leonardus Wendelinus Mathias Marie

    2013-01-01

    A variety of filters assays have been described to enrich circulating tumor cells (CTC) based on differences in physical characteristics of blood cells and CTC. In this study we evaluate different filter types to derive the properties of the ideal filter for CTC enrichment. Between 0.1 and 10 mL of

  10. Filter Characteristics Influencing Circulating Tumor Cell Enrichment from Whole Blood

    NARCIS (Netherlands)

    Coumans, Frank A. W.; van Dalum, Guus; Beck, Markus; Terstappen, Leon W. M. M.

    2013-01-01

    A variety of filters assays have been described to enrich circulating tumor cells (CTC) based on differences in physical characteristics of blood cells and CTC. In this study we evaluate different filter types to derive the properties of the ideal filter for CTC enrichment. Between 0.1 and 10 mL of

  11. HIV-1 isolation from infected peripheral blood mononuclear cells

    NARCIS (Netherlands)

    Dispinseri, Stefania; Saba, Elisa; Vicenzi, Elisa; Kootstra, Neeltje A.; Schuitemaker, Hanneke; Scarlatti, Gabriella

    2014-01-01

    Human immunodeficiency virus 1 (HIV-1) isolation from peripheral blood mononuclear cells (PBMCs) allows retrieval of replication-competent viral variants. In order to impose the smallest possible selective pressure on the viral isolates, isolation must be carried out in primary cultures of cells and

  12. Challenges for red blood cell biomarker discovery through proteomics

    NARCIS (Netherlands)

    Barasa, B.A.|info:eu-repo/dai/nl/341538353; Slijper, M.|info:eu-repo/dai/nl/146303989

    2014-01-01

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

  13. Determinants of resting cerebral blood flow in sickle cell disease

    NARCIS (Netherlands)

    Bush, Adam M.; Borzage, Matthew T.; Choi, Soyoung; Václavů, Lena; Tamrazi, Benita; Nederveen, Aart J.; Coates, Thomas D.; Wood, John C.

    2016-01-01

    Stroke is common in children with sickle cell disease and results from an imbalance in oxygen supply and demand. Cerebral blood flow (CBF) is increased in patients with sickle cell disease to compensate for their anemia, but adequacy of their oxygen delivery has not been systematically demonstrated.

  14. Effects of Septrin Administration on Blood Cells Parameters in Humans

    African Journals Online (AJOL)

    The results showed that the packed cell volume (PCV), total white blood cell count (WBC), neutrophils and platelets were significantly decreased (p<0.05), especially after 7-10 days of septrin administration, compared to the control values. On the other hand, the reticulocytes, lymphocytes, eosinophils and prothrombin time ...

  15. Blood thixotropy in patients with sickle cell anaemia: role of haematocrit and red blood cell rheological properties.

    Directory of Open Access Journals (Sweden)

    Jens Vent-Schmidt

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

  16. Rapid white blood cell detection for peritonitis diagnosis

    Science.gov (United States)

    Wu, Tsung-Feng; Mei, Zhe; Chiu, Yu-Jui; Cho, Sung Hwan; Lo, Yu-Hwa

    2013-03-01

    A point-of-care and home-care lab-on-a-chip (LoC) system that integrates a microfluidic spiral device as a concentrator with an optical-coding device as a cell enumerator is demonstrated. The LoC system enumerates white blood cells from dialysis effluent of patients receiving peritoneal dialysis. The preliminary results show that the white blood cell counts from our system agree well with the results from commercial flow cytometers. The LoC system can potentially bring significant benefits to end stage renal disease (ESRD) patients that are on peritoneal dialysis (PD).

  17. IL2rg Cytokines Enhance Umbilical Cord Blood CD34+ Cells Differentiation to T Cells

    Science.gov (United States)

    Aliyari, Zeynab; Soleimanirad, Sara; Sayyah Melli, Manizheh; Tayefi Nasrabadi, Hamid; Nozad Charoudeh, Hojjatollah

    2015-01-01

    Purpose: Umbilical cord blood (UCB) is an alternative source of hematopoietic stem cell (HSC) transplantation for the treatment of patients with leukemia if matched donor is not available. CD34+ is a pan marker for human hematopoietic stem cells, including umbilical cord blood stem cell. In comparison to other sources, cord blood CD34+ cells proliferate more rapidly and produce large number of progeny cells. For ex vivo expansion of Umbilical Cord Blood- HSCs/HPCs, different combinations of cytokines have been used in many laboratories. IL2rg cytokines, including IL2, IL7 and IL15, are key cytokines in the regulation of differentiation, proliferation and survival of immune cells. IL2 is important cytokine for T cell survival and proliferation, IL7 involve in B cell development and IL15 is a key cytokine for NK cell development. In this study we evaluated the generation of T cells derived from CD34+ and CD34- cord blood mononuclear cells by using combination of cytokines including IL2, IL7 and IL15. Methods: Cultured cord blood mononuclear cells were evaluated at distinct time points during 21 days by using flow cytometry. Results: Present study showed that differentiation of T cells derived from CD34+ cord blood mononuclear cells increased by using IL2 and IL7 at different time points. In the other hand IL15 did not show any significant role in generation of T cells from CD34+ cord blood mononuclear cells. Conclusion: Taken together, our data illustrated that either IL2 or IL7 versus other cytokine combinations, generate more T cell from cord blood CD34 cells, probably this cytokines can be the best condition for ex vivo expansion of UCB HSCs. PMID:26793606

  18. Effect of Induced Pluripotent Stem Cell Technology in Blood Banking.

    Science.gov (United States)

    Focosi, Daniele; Pistello, Mauro

    2016-03-01

    Population aging has imposed cost-effective alternatives to blood donations. Artificial blood is still at the preliminary stages of development, and the need for viable cells seems unsurmountable. Because large numbers of viable cells must be promptly available for clinical use, stem cell technologies, expansion, and banking represent ideal tools to ensure a regular supply. Provided key donors can be identified, induced pluripotent stem cell (iPSC) technology could pave the way to a new era in transfusion medicine, just as it is already doing in many other fields of medicine. The present review summarizes the current state of research on iPSC technology in the field of blood banking, highlighting hurdles, and promises. ©AlphaMed Press.

  19. Spatial-spectral blood cell classification with microscopic hyperspectral imagery

    Science.gov (United States)

    Ran, Qiong; Chang, Lan; Li, Wei; Xu, Xiaofeng

    2017-10-01

    Microscopic hyperspectral images provide a new way for blood cell examination. The hyperspectral imagery can greatly facilitate the classification of different blood cells. In this paper, the microscopic hyperspectral images are acquired by connecting the microscope and the hyperspectral imager, and then tested for blood cell classification. For combined use of the spectral and spatial information provided by hyperspectral images, a spatial-spectral classification method is improved from the classical extreme learning machine (ELM) by integrating spatial context into the image classification task with Markov random field (MRF) model. Comparisons are done among ELM, ELM-MRF, support vector machines(SVM) and SVMMRF methods. Results show the spatial-spectral classification methods(ELM-MRF, SVM-MRF) perform better than pixel-based methods(ELM, SVM), and the proposed ELM-MRF has higher precision and show more accurate location of cells.

  20. Oxygen release and exchange in niobium oxide MEHPPV hybrid solar cells

    DEFF Research Database (Denmark)

    Lira-Cantu, M.; Norrman, K.; Andreasen, J.W.

    2006-01-01

    We demonstrate that niobium oxide exchanges oxygen with the atmosphere when illuminated by simulated sunlight. The oxygen exchange was found to take place for pristine niobium oxide films when illuminated in an oxygen atmosphere and when illuminated in an operational hybrid solar cell. The oxygen...... exchange was demonstrated using O-18(2)-isotopic labeling in combination with time-of-flight secondary ion mass spectrometry (TOF-SIMS) imaging analysis of devices and oxide substrates. TOF-SIMS depth profiling confirmed O-18 incorporation throughout the device in hybrid solar cells. The results...... are discussed in the context of hybrid solar cell stability and illuminate one of the degradation paths....

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

    International Nuclear Information System (INIS)

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

    2005-01-01

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

  2. Changes in blood lactate and respiratory gas exchange measures in sports with discontinuous load profiles.

    Science.gov (United States)

    Smekal, Gerhard; von Duvillard, Serge P; Pokan, Rochus; Tschan, Harald; Baron, Ramon; Hofmann, Peter; Wonisch, Manfred; Bachl, Norbert

    2003-06-01

    This study compares two different sport events (orienteering = OTC; tennis = TEC) with discontinuous load profiles and different activity/recovery patterns by means of blood lactate (LA), heart rate (HR), and respiratory gas exchange measures (RGME) determined via a portable respiratory system. During the TEC, 20 tennis-ranked male subjects [age: 26.0 (3.7) years; height: 181.0 (5.7) cm; weight: 73.2 (6.8) kg; maximal oxygen consumption (VO(2)max): 57.3 (5.1) ml.kg(-1).min(-1)] played ten matches of 50 min. During the OTC, 11 male members of the Austrian National Team [age: 23.5 (3.9) years; height: 183.6 (6.8) cm; weight: 72.4 (3.9) kg; VO(2)max: 67.9 (3.8) ml.kg(-1).min(-1)] performed a simulated OTC (six sections; average length: 10.090 m). In both studies data from the maximal treadmill tests (TT) were used as reference values for the comparison of energy expenditure of OTC and TEC. During TEC, the average VO(2) was considerably lower [29.1 (5.6) ml(.)kg(-1.)min(-1)] or 51.1 (10.9)% of VO(2)max and 64.8.0 (13.3)% of VO(2) determined at the individual anaerobic threshold (IAT) on the TT. The short high-intensity periods (activity/recovery = 1/6) did not result in higher LA levels [average LA of games: 2.07 (0.9) mmol.l(-1)]. The highest average VO(2 )value for a whole game was 47.8 ml.kg(-1.)min(-1) and may provide a reference for energy demands required to sustain high-intensity periods of tennis predominantly via aerobic mechanism of energy delivery. During OTC, we found an average VO(2) of 56.4 (4.5) ml.kg(-1).min(-1) or 83.0 (3.8)% of VO(2)max and 94.6 (5.2)% of VO(2) at IAT. In contrast to TEC, LA were relatively high [5.16 (1.5) mmol.l(-1)) although the average VO(2) was significantly lower than VO(2) at IAT. Our data suggest that portable RGEM provides valuable information concerning the energy expenditure in sports that cannot be interpreted from LA or HR measures alone. Portable RGEM systems provide valuable assessment of under- or over-estimation of

  3. Filtration Parameters Influencing Circulating Tumor Cell Enrichment from Whole Blood

    Science.gov (United States)

    Beck, Markus; Terstappen, Leon W. M. M.

    2013-01-01

    Filtration can achieve circulating tumor cell (CTC) enrichment from blood. Key parameters such as flow-rate, applied pressure, and fixation, vary largely between assays and their influence is not well understood. Here, we used a filtration system, to monitor these parameters and determine their relationships. Whole blood, or its components, with and without spiked tumor cells were filtered through track-etched filters. We characterize cells passing through filter pores by their apparent viscosity; the viscosity of a fluid that would pass with the same flow. We measured a ratio of 5·104∶102∶1 for the apparent viscosities of 15 µm diameter MDA-231 cells, 10 µm white cells and 90 fl red cells passing through a 5 µm pore. Fixation increases the pressure needed to pass cells through 8 µm pores 25-fold and halves the recovery of spiked tumor cells. Filtration should be performed on unfixed samples at a pressure of ∼10 mbar for a 1 cm2 track-etched filter with 5 µm pores. At this pressure MDA-231 cells move through the filter in 1 hour. If fixation is needed for sample preservation, a gentle fixative should be selected. The difference in apparent viscosity between CTC and blood cells is key in optimizing recovery of CTC. PMID:23658615

  4. Filtration parameters influencing circulating tumor cell enrichment from whole blood.

    Directory of Open Access Journals (Sweden)

    Frank A W Coumans

    Full Text Available Filtration can achieve circulating tumor cell (CTC enrichment from blood. Key parameters such as flow-rate, applied pressure, and fixation, vary largely between assays and their influence is not well understood. Here, we used a filtration system, to monitor these parameters and determine their relationships. Whole blood, or its components, with and without spiked tumor cells were filtered through track-etched filters. We characterize cells passing through filter pores by their apparent viscosity; the viscosity of a fluid that would pass with the same flow. We measured a ratio of 5·10(4∶10(2∶1 for the apparent viscosities of 15 µm diameter MDA-231 cells, 10 µm white cells and 90 fl red cells passing through a 5 µm pore. Fixation increases the pressure needed to pass cells through 8 µm pores 25-fold and halves the recovery of spiked tumor cells. Filtration should be performed on unfixed samples at a pressure of ∼10 mbar for a 1 cm(2 track-etched filter with 5 µm pores. At this pressure MDA-231 cells move through the filter in 1 hour. If fixation is needed for sample preservation, a gentle fixative should be selected. The difference in apparent viscosity between CTC and blood cells is key in optimizing recovery of CTC.

  5. On the Mechanism of Human Red Blood Cell Longevity: Roles of Calcium, the Sodium Pump, PIEZO1, and Gardos Channels

    Directory of Open Access Journals (Sweden)

    Virgilio L. Lew

    2017-12-01

    Full Text Available In a healthy adult, the transport of O2 and CO2 between lungs and tissues is performed by about 2 · 1013 red blood cells, of which around 1.7 · 1011 are renewed every day, a turnover resulting from an average circulatory lifespan of about 120 days. Cellular lifespan is the result of an evolutionary balance between the energy costs of maintaining cells in a fit functional state versus cell renewal. In this Review we examine how the set of passive and active membrane transporters of the mature red blood cells interact to maximize their circulatory longevity thus minimizing costs on expensive cell turnover. Red blood cell deformability is critical for optimal rheology and gas exchange functionality during capillary flow, best fulfilled when the volume of each human red blood cell is kept at a fraction of about 0.55–0.60 of the maximal spherical volume allowed by its membrane area, the optimal-volume-ratio range. The extent to which red blood cell volumes can be preserved within or near these narrow optimal-volume-ratio margins determines the potential for circulatory longevity. We show that the low cation permeability of red blood cells allows volume stability to be achieved with extraordinary cost-efficiency, favouring cell longevity over cell turnover. We suggest a mechanism by which the interplay of a declining sodium pump and two passive membrane transporters, the mechanosensitive PIEZO1 channel, a candidate mediator of Psickle in sickle cells, and the Ca2+-sensitive, K+-selective Gardos channel, can implement red blood cell volume stability around the optimal-volume-ratio range, as required for extended circulatory longevity.

  6. Red blood cell image enhancement techniques for cells with ...

    African Journals Online (AJOL)

    quality or challenging conditions of the images such as poor illumination of blood smear and most importantly overlapping RBC. The algorithm comprises of two RBC segmentation that can be selected based on the image quality, circle mask technique and grayscale blood smear image processing. Detail explanations ...

  7. Ion transport resistance in Microbial Electrolysis Cells with anion and cation exchange membranes

    NARCIS (Netherlands)

    Sleutels, T.H.J.A.; Hamelers, H.V.M.; Rozendal, R.A.; Buisman, C.J.N.

    2009-01-01

    Previous studies have shown that Microbial Electrolysis Cells (MECs) perform better when an anion exchange membrane (AEM) than when a cation exchange membrane (CEM) separates the electrode chambers. Here, we have further studied this phenomenon by comparing two analysis methods for

  8. Measuring osmosis and hemolysis of red blood cells.

    Science.gov (United States)

    Goodhead, Lauren K; MacMillan, Frances M

    2017-06-01

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

  9. Allogeneic red blood cell transfusions: efficacy, risks, alternatives and indications

    OpenAIRE

    Madjdpour, C.; Spahn, D. R.

    2017-01-01

    Careful assessment of risks and benefits has to precede each decision on allogeneic red blood cell (RBC) transfusion. Currently, a number of key issues in transfusion medicine are highly controversial, most importantly the influence of different transfusion thresholds on clinical outcome. The aim of this article is to review current evidence on blood transfusions, to highlight ‘hot topics' with respect to efficacy, outcome and risks, and to provide the reader with transfusion guidelines. In a...

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

    International Nuclear Information System (INIS)

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

    1988-01-01

    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

  11. Potential uses for cord blood mesenchymal stem cells.

    Science.gov (United States)

    Zarrabi, Morteza; Mousavi, Seyed Hadi; Abroun, Saeid; Sadeghi, Bahareh

    2014-01-01

    Stem cell therapy is a powerful technique for the treatment of a number of diseases. Stem cells are derived from different tissue sources, the most important of which are the bone marrow (BM), umbilical cord (UC) blood and liver. Human UC mesenchymal stem cells (hUC-MSCs) are multipotent, non-hematopoietic stem cells that have the ability to self-renew and differentiate into other cells and tissues such as osteoblasts, adipocytes and chondroblasts. In a number of reports, human and mouse models of disease have hUC-MSCs treatments. In this article, we review studies that pertain to the use of hUC-MSCs as treatment for diseases.

  12. Chaotic Dynamics of Red Blood Cells in a Sinusoidal Flow

    Science.gov (United States)

    Dupire, Jules; Abkarian, Manouk; Viallat, Annie

    2010-04-01

    We show that the motion of individual red blood cells in an oscillating moderate shear flow is described by a nonlinear system of three coupled oscillators. Our experiments reveal that the cell tank treads and tumbles either in a stable way with synchronized cell inclination, membrane rotation and hydrodynamic oscillations, or in an irregular way, very sensitively to initial conditions. By adapting our model described previously, we determine the theoretical diagram for the red cell motion in a sinusoidal flow close to physiological shear stresses and flow variation frequencies and reveal large domains of chaotic motions. Finally, fitting our observations allows a characterization of cell viscosity and membrane elasticity.

  13. On-chip Extraction of Intracellular Molecules in White Blood Cells from Whole Blood

    Science.gov (United States)

    Choi, Jongchan; Hyun, Ji-Chul; Yang, Sung

    2015-10-01

    The extraction of virological markers in white blood cells (WBCs) from whole blood—without reagents, electricity, or instruments—is the most important first step for diagnostic testing of infectious diseases in resource-limited settings. Here we develop an integrated microfluidic chip that continuously separates WBCs from whole blood and mechanically ruptures them to extract intracellular proteins and nucleic acids for diagnostic purposes. The integrated chip is assembled with a device that separates WBCs by using differences in blood cell size and a mechanical cell lysis chip with ultra-sharp nanoblade arrays. We demonstrate the performance of the integrated device by quantitatively analyzing the levels of extracted intracellular proteins and genomic DNAs. Our results show that compared with a conventional method, the device yields 120% higher level of total protein amount and similar levels of gDNA (90.3%). To demonstrate its clinical application to human immunodeficiency virus (HIV) diagnostics, the developed chip was used to process blood samples containing HIV-infected cells. Based on PCR results, we demonstrate that the chip can extract HIV proviral DNAs from infected cells with a population as low as 102/μl. These findings suggest that the developed device has potential application in point-of-care testing for infectious diseases in developing countries.

  14. Use of cryopreserved peripheral mononuclear blood cells in biomonitoring

    DEFF Research Database (Denmark)

    Risom, Lotte; Knudsen, Lisbeth E.

    1999-01-01

    This study was performed to investigate the effect of storing blood samples by freezing on selected biomarkers and possible implications for biomonitoring. Comparative measurements were performed in order to investigate the use of cryopreserved vs. freshly separated peripheral mononuclear blood...... cells (PMBC) obtained from donor blood. Measurements of DNA-repair, mutant frequency, and subcell content were included. Samples for large biomonitoring studies are usually taken from study groups within a short time period of days/weeks and storing of study material for later analysis can be necessary...

  15. Synthesis and characterisation of alkaline anionic-exchange membranes for direct alcohol fuel cells

    CSIR Research Space (South Africa)

    Nonjola, P

    2007-12-01

    Full Text Available , but the most important being proton exchange membrane fuel cell (PEMFC), which uses an acidic membrane like Nafion (sulfonated fluorocarbon polymers) as an electrolyte. The use of polymer electrolytes represents an interesting path to pursue...

  16. White blood cell subtypes and risk of type 2 diabetes.

    Science.gov (United States)

    Zhang, Hongmei; Yang, Zhen; Zhang, Weiwei; Niu, Yixin; Li, Xiaoyong; Qin, Li; Su, Qing

    2017-01-01

    It is reported that total white blood cell is associated with risk of diabetes mellitus. The present study is to investigate the relationship of white blood cell subsets with incidence of type 2 diabetes at baseline and 3year follow-up. We chose individuals without diabetes history as our study population; 8991 individuals were included at baseline. All of the participants underwent a 75-g OGTT at baseline. White blood cell count including all the subsets were measured along with all the other laboratory indices. The participants who were not diagnosed with type 2 diabetes according to the WHO 1999 diagnostic criteria underwent another 75-g OGTT at 3year follow-up. The total WBC count, neutrophil count, and lymphocyte count were significantly increased in subjects newly diagnosed with diabetes mellitus compared to non-DM subjects at baseline (all ptype 2 diabetes. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. State of the science of blood cell labeling

    International Nuclear Information System (INIS)

    Srivastava, S.C.; Straub, R.F.

    1989-01-01

    Blood cell labeling can be considered a science in as far as it is based on precise knowledge and can be readily reproduced. This benchmark criterion is applied to all current cell labeling modalities and their relative merits and deficiencies are discussed. Mechanisms are given where they are known as well as labeling yields, label stability, and cell functionality. The focus is on the methodology and its suitability to the clinical setting rather than on clinical applications per se. Clinical results are cited only as proof of efficacy of the various methods. The emphasis is on technetium as the cell label, although comparisons are made between technetium and indium, and all blood cells are covered. 52 refs., 6 figs., 7 tabs

  18. Phagocytotic labelling of migratory blood cells and it clinical applications

    International Nuclear Information System (INIS)

    Oberhausen, E.; Schroth, H.J.

    1984-01-01

    A method for the labelling of monocytes and granulocytes with 99m-Tc-Sn-colloid in whole blood is described. The basis of the method is the phagocytosis of the Sn-colloid by the monocytes and granulocytes. There is the disadvantage that more than half of the activity is accumulated in the liver and spleen after the reinjection of labelled cells. Experiments in rats have revealed that about 90% of the administered cell bound activity were removed from the circulation and were taken up in the liver and spleen. By venipuncture of such a rat it was possible to remove circulating labelled cells of which, on reinjection into a second rat, about one half remiained in the circulation. This evidence indicated that phagocytotic tagging of white blood cells with 99m-Tc-Sn-colloid yielded viable, labelled cells. (Auth.)

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

    Science.gov (United States)

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

    2016-06-01

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

  20. The DNA methylome of human peripheral blood mononuclear cells

    DEFF Research Database (Denmark)

    Li, Yingrui; Zhu, Jingde; Tian, Geng

    2010-01-01

    DNA methylation plays an important role in biological processes in human health and disease. Recent technological advances allow unbiased whole-genome DNA methylation (methylome) analysis to be carried out on human cells. Using whole-genome bisulfite sequencing at 24.7-fold coverage (12.3-fold per...... strand), we report a comprehensive (92.62%) methylome and analysis of the unique sequences in human peripheral blood mononuclear cells (PBMC) from the same Asian individual whose genome was deciphered in the YH project. PBMC constitute an important source for clinical blood tests world-wide. We found...

  1. Aquatic flower-inspired cell culture platform with simplified medium exchange process for facilitating cell-surface interaction studies.

    Science.gov (United States)

    Hong, Hyeonjun; Park, Sung Jea; Han, Seon Jin; Lim, Jiwon; Kim, Dong Sung

    2016-02-01

    Establishing fundamentals for regulating cell behavior with engineered physical environments, such as topography and stiffness, requires a large number of cell culture experiments. However, cell culture experiments in cell-surface interaction studies are generally labor-intensive and time-consuming due to many experimental tasks, such as multiple fabrication processes in sample preparation and repetitive medium exchange in cell culture. In this work, a novel aquatic flower-inspired cell culture platform (AFIP) is presented. AFIP aims to facilitate the experiments on the cell-surface interaction studies, especially the medium exchange process. AFIP was devised to capture and dispense cell culture medium based on interactions between an elastic polymer substrate and a liquid medium. Thus, the medium exchange can be performed easily and without the need of other instruments, such as a vacuum suction and pipette. An appropriate design window of AFIP, based on scaling analysis, was identified to provide a criterion for achieving stability in medium exchange as well as various surface characteristics of the petal substrates. The developed AFIP, with physically engineered petal substrates, was also verified to exchange medium reliably and repeatedly. A closed structure capturing the medium was sustained stably during cell culture experiments. NIH3T3 proliferation results also demonstrated that AFIP can be applied to the cell-surface interaction studies as an alternative to the conventional method.

  2. Dynamic Simulation of a Proton Exchange Membrane Fuel Cell System For Automotive Applications

    DEFF Research Database (Denmark)

    Rabbani, Raja Abid; Rokni, Masoud

    2012-01-01

    A dynamic model of the PEMFC system is developed to investigate the behaviour and transient response of the fuel cell system for automotive applications. The system accounts for the fuel cell stack with coolant, humidifier, heat exchangers and pumps. Governing equations for fuel cell and humidifier...

  3. Lack of NMDA receptor subunit exchange alters Purkinje cell dendritic morphology in cerebellar slice cultures

    NARCIS (Netherlands)

    Metzger, F; Pieri, [No Value; Eisel, ULM; Pieri, Isabelle

    2005-01-01

    Early postnatal developmental changes in N-methyl-D-aspartate (NMDA) receptor (NR) subunits regulate cerebellar granule cell maturation and potentially Purkinje cell development. We therefore investigated Purkinje cell morphology in slice cultures from mice with genetic subunit exchange from NR2C to

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

    DEFF Research Database (Denmark)

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

    2013-01-01

    The blood group Vel was discovered 60 years ago, but the underlying gene is unknown. Individuals negative for the Vel antigen are rare and are required for the safe transfusion of patients with antibodies to Vel. To identify the responsible gene, we sequenced the exomes of five individuals negative...... and expression of the Vel antigen on SMIM1-transfected cells confirm SMIM1 as the gene underlying the Vel blood group. An expression quantitative trait locus (eQTL), the common SNP rs1175550 contributes to variable expression of the Vel antigen (P = 0.003) and influences the mean hemoglobin concentration of red...... blood cells (RBCs; P = 8.6 × 10(-15)). In vivo, zebrafish with smim1 knockdown showed a mild reduction in the number of RBCs, identifying SMIM1 as a new regulator of RBC formation. Our findings are of immediate relevance, as the homozygous presence of the deletion allows the unequivocal identification...

  5. Daily variation in radiosensitivity of circulating blood cells and bone marrow cell density in mice

    International Nuclear Information System (INIS)

    Tabatabai, R.N.

    1984-01-01

    Mice on a 12/12 light/dark cycle were bled during a twenty-four hour period each week for eight weeks to establish daily values of circulating blood cells. No significant daily variation was found in total red blood cells, hematocrit, or percentage of reticulocytes. A significant (P < 0.001) daily variation was found in total white blood cells, with the minimum occurring at 8 PM and the maximum occurring during the daylight hours from 8 a.m. to 2 p.m. Mice were then exposed to 0 R, 20 R, 50 R, or 100 R of x-radiation to determine what dose significantly reduces the total white cell count in circulating blood. It was found that 100 R significantly (P < .05) reduces the total white cell count over a four week period post-exposure. To determine if circulating blood cells and bone marrow cells show a diurnal radiosensitivity, mice were exposed to 100 R or 200 R of x-radiation at noon or midnight. Hematocrits, reticulocyte and white blood cell counts, daily white blood cell rhythm, and bone marrow cell density indicate that these mice were more radiosensitive at night

  6. A color and shape based algorithm for segmentation of white blood cells in peripheral blood and bone marrow images.

    Science.gov (United States)

    Arslan, Salim; Ozyurek, Emel; Gunduz-Demir, Cigdem

    2014-06-01

    Computer-based imaging systems are becoming important tools for quantitative assessment of peripheral blood and bone marrow samples to help experts diagnose blood disorders such as acute leukemia. These systems generally initiate a segmentation stage where white blood cells are separated from the background and other nonsalient objects. As the success of such imaging systems mainly depends on the accuracy of this stage, studies attach great importance for developing accurate segmentation algorithms. Although previous studies give promising results for segmentation of sparsely distributed normal white blood cells, only a few of them focus on segmenting touching and overlapping cell clusters, which is usually the case when leukemic cells are present. In this article, we present a new algorithm for segmentation of both normal and leukemic cells in peripheral blood and bone marrow images. In this algorithm, we propose to model color and shape characteristics of white blood cells by defining two transformations and introduce an efficient use of these transformations in a marker-controlled watershed algorithm. Particularly, these domain specific characteristics are used to identify markers and define the marking function of the watershed algorithm as well as to eliminate false white blood cells in a postprocessing step. Working on 650 white blood cells in peripheral blood and bone marrow images, our experiments reveal that the proposed algorithm improves the segmentation performance compared with its counterparts, leading to high accuracies for both sparsely distributed normal white blood cells and dense leukemic cell clusters. © 2014 International Society for Advancement of Cytometry.

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

    Directory of Open Access Journals (Sweden)

    V. V. Moroz

    2012-01-01

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

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

    Science.gov (United States)

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

    2017-03-01

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

  9. Alkaline Exchange Membrane (AEM) for High-Efficiency Fuel Cells, Electrolyzers and Regenerative Fuel Cell Systems Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Develop an alkaline exchange membrane (AEM)for use as a polymer electrolyte in both fuel cell and electrolyzer systems.  The ultimate goal in AEM development is...

  10. The productivity limit of manufacturing blood cell therapy in scalable stirred bioreactors

    Science.gov (United States)

    Bayley, Rachel; Ahmed, Forhad; Glen, Katie; McCall, Mark; Stacey, Adrian

    2017-01-01

    Abstract Manufacture of red blood cells (RBCs) from progenitors has been proposed as a method to reduce reliance on donors. Such a process would need to be extremely efficient for economic viability given a relatively low value product and high (2 × 1012) cell dose. Therefore, the aim of these studies was to define the productivity of an industry standard stirred‐tank bioreactor and determine engineering limitations of commercial red blood cells production. Cord blood derived CD34+ cells were cultured under erythroid differentiation conditions in a stirred micro‐bioreactor (Ambr™). Enucleated cells of 80% purity could be created under optimal physical conditions: pH 7.5, 50% oxygen, without gas‐sparging (which damaged cells) and with mechanical agitation (which directly increased enucleation). O2 consumption was low (~5 × 10–8 μg/cell.h) theoretically enabling erythroblast densities in excess of 5 × 108/ml in commercial bioreactors and sub‐10 l/unit production volumes. The bioreactor process achieved a 24% and 42% reduction in media volume and culture time, respectively, relative to unoptimized flask processing. However, media exchange limited productivity to 1 unit of erythroblasts per 500 l of media. Systematic replacement of media constituents, as well as screening for inhibitory levels of ammonia, lactate and key cytokines did not identify a reason for this limitation. We conclude that the properties of erythroblasts are such that the conventional constraints on cell manufacturing efficiency, such as mass transfer and metabolic demand, should not prevent high intensity production; furthermore, this could be achieved in industry standard equipment. However, identification and removal of an inhibitory mediator is required to enable these economies to be realized. Copyright © 2016 The Authors Journal of Tissue Engineering and Regenerative Medicine Published by John Wiley & Sons Ltd. PMID:27696710

  11. Laser-photophoretic migration and fractionation of human blood cells

    International Nuclear Information System (INIS)

    Monjushiro, Hideaki; Tanahashi, Yuko; Watarai, Hitoshi

    2013-01-01

    Graphical abstract: -- Highlights: •RBCs were migrated faster than WBCs and blood pellets by laser photophoresis. •Photophoretic efficiency of RBC and WBC was simulated by the Mie scattering theory. •Spontaneous orientation of RBC parallel to the migration direction was elucidated. •Laser photophoretic separation of RBC and WBC was possible in a tip flow system. -- Abstract: Laser photophoretic migration behavior of human blood cells in saline solution was investigated under the irradiation of Nd:YAG laser beam (532 nm) in the absence and the presence of the flow in a fused silica capillary. Red blood cells (RBC) were migrated faster than white blood cells (WBC) and blood pellets to the direction of propagation of laser light. The observed photophoretic velocity of RBC was about 11 times faster than those of others. This was understood from the larger photophoretic efficiency of RBC than that of WBC, which was simulated based on the Mie scattering theory. Furthermore, it was found that, during the photophoretic migration, RBCs spontaneously orientated parallel to the migration direction so as to reduce the drag force. Finally, it was demonstrated that RBC and WBC were separated in a micro-channel flow system by the laser photophoresis

  12. Laser-photophoretic migration and fractionation of human blood cells

    Energy Technology Data Exchange (ETDEWEB)

    Monjushiro, Hideaki; Tanahashi, Yuko; Watarai, Hitoshi, E-mail: watarai@chem.sci.osaka-u.ac.jp

    2013-05-13

    Graphical abstract: -- Highlights: •RBCs were migrated faster than WBCs and blood pellets by laser photophoresis. •Photophoretic efficiency of RBC and WBC was simulated by the Mie scattering theory. •Spontaneous orientation of RBC parallel to the migration direction was elucidated. •Laser photophoretic separation of RBC and WBC was possible in a tip flow system. -- Abstract: Laser photophoretic migration behavior of human blood cells in saline solution was investigated under the irradiation of Nd:YAG laser beam (532 nm) in the absence and the presence of the flow in a fused silica capillary. Red blood cells (RBC) were migrated faster than white blood cells (WBC) and blood pellets to the direction of propagation of laser light. The observed photophoretic velocity of RBC was about 11 times faster than those of others. This was understood from the larger photophoretic efficiency of RBC than that of WBC, which was simulated based on the Mie scattering theory. Furthermore, it was found that, during the photophoretic migration, RBCs spontaneously orientated parallel to the migration direction so as to reduce the drag force. Finally, it was demonstrated that RBC and WBC were separated in a micro-channel flow system by the laser photophoresis.

  13. Determination of blood cell subtype concentrations from frozen whole blood samples using TruCount beads.

    Science.gov (United States)

    Langenskiöld, Cecilia; Mellgren, Karin; Abrahamsson, Jonas; Bemark, Mats

    2016-06-24

    In many studies it would be advantageous if blood samples could be collected and analyzed using flow cytometry at a later stage. Ideally, sample collection should involve little hands-on time, allow for long-term storage, and minimally influence the samples. Here we establish a flow cytometry antibody panel that can be used to determine granulocytes, monocytes, and lymphocyte subset concentrations in fresh and frozen whole blood using TruCount technology. The panel can be used on fresh whole-blood samples as well as whole-blood samples that have been frozen after mixing with 10% DMSO. Concentrations in frozen and fresh sample is highly correlated both when frozen within 4 h and the day after collection (r ≥ 0.98), and the estimated concentration in frozen samples was between 91 and 94% of that in fresh samples for all cell types. Using this method whole-blood samples can be frozen using a simple preparation method, and stored long-term before accurate determination of cell concentration. This allows for standardized analysis of the samples at a reference laboratory in multi-center studies. © 2016 International Clinical Cytometry Society. © 2016 International Clinical Cytometry Society.

  14. Induced Pluripotent Stem Cell Generation from Blood Cells Using Sendai Virus and Centrifugation.

    Science.gov (United States)

    Rim, Yeri Alice; Nam, Yoojun; Ju, Ji Hyeon

    2016-12-21

    The recent development of human induced pluripotent stem cells (hiPSCs) proved that mature somatic cells can return to an undifferentiated, pluripotent state. Now, reprogramming is done with various types of adult somatic cells: keratinocytes, urine cells, fibroblasts, etc. Early experiments were usually done with dermal fibroblasts. However, this required an invasive surgical procedure to obtain fibroblasts from the patients. Therefore, suspension cells, such as blood and urine cells, were considered ideal for reprogramming because of the convenience of obtaining the primary cells. Here, we report an efficient protocol for iPSC generation from peripheral blood mononuclear cells (PBMCs). By plating the transduced PBMCs serially to a new, matrix-coated plate using centrifugation, this protocol can easily provide iPSC colonies. This method is also applicable to umbilical cord blood mononuclear cells (CBMCs). This study presents a simple and efficient protocol for the reprogramming of PBMCs and CBMCs.

  15. AT cells are not radiosensitive for simple chromosomal exchanges at low dose

    Energy Technology Data Exchange (ETDEWEB)

    Hada, Megumi; Huff, Janice L.; Patel, Zarana S. [USRA Division of Life Sciences, Houston, TX 77058 (United States); Kawata, Tetsuya [Department of Radiology, School of Medicine, Keio University, Tokyo (Japan); Pluth, Janice M. [Lawrence Berkeley National Laboratory, Life Sciences Division, One Cyclotron Road, Building 74, Berkeley, CA 94720 (United States); George, Kerry A. [Wyle, 1290 Hercules Drive, Houston, TX 77058 (United States); Cucinotta, Francis A., E-mail: Francis.A.Cucinotta@nasa.gov [NASA, Lyndon B. Johnson Space Center, 2101 NASA Parkway, Houston, TX 77058 (United States)

    2011-11-01

    Cells deficient in ATM (product of the gene that is mutated in ataxia telangiectasia patients) or NBS (product of the gene mutated in the Nijmegen breakage syndrome) show increased yields of both simple and complex chromosomal aberrations after high doses (>0.5 Gy) of ionizing radiation (X-rays or {gamma}-rays), however less is known on how these cells respond at low dose. Previously we had shown that the increased chromosome aberrations in ATM and NBS defective lines was due to a significantly larger quadratic dose-response term compared to normal fibroblasts for both simple and complex exchanges. The linear dose-response term for simple exchanges was significantly higher in NBS cells compared to wild type cells, but not for AT cells. However, AT cells have a high background level of exchanges compared to wild type or NBS cells that confounds the understanding of low dose responses. To understand the sensitivity differences for high to low doses, chromosomal aberration analysis was first performed at low dose-rates (0.5 Gy/d), and results provided further evidence for the lack of sensitivity for exchanges in AT cells below doses of 1 Gy. Normal lung fibroblast cells treated with KU-55933, a specific ATM kinase inhibitor, showed increased numbers of exchanges at a dose of 1 Gy and higher, but were similar to wild type cells at 0.5 Gy or below. These results were confirmed using siRNA knockdown of ATM. The present study provides evidence that the increased radiation sensitivity of AT cells for chromosomal exchanges found at high dose does not occur at low dose.

  16. AT cells are not radiosensitive for simple chromosomal exchanges at low dose

    International Nuclear Information System (INIS)

    Hada, Megumi; Huff, Janice L.; Patel, Zarana S.; Kawata, Tetsuya; Pluth, Janice M.; George, Kerry A.; Cucinotta, Francis A.

    2011-01-01

    Cells deficient in ATM (product of the gene that is mutated in ataxia telangiectasia patients) or NBS (product of the gene mutated in the Nijmegen breakage syndrome) show increased yields of both simple and complex chromosomal aberrations after high doses (>0.5 Gy) of ionizing radiation (X-rays or γ-rays), however less is known on how these cells respond at low dose. Previously we had shown that the increased chromosome aberrations in ATM and NBS defective lines was due to a significantly larger quadratic dose-response term compared to normal fibroblasts for both simple and complex exchanges. The linear dose-response term for simple exchanges was significantly higher in NBS cells compared to wild type cells, but not for AT cells. However, AT cells have a high background level of exchanges compared to wild type or NBS cells that confounds the understanding of low dose responses. To understand the sensitivity differences for high to low doses, chromosomal aberration analysis was first performed at low dose-rates (0.5 Gy/d), and results provided further evidence for the lack of sensitivity for exchanges in AT cells below doses of 1 Gy. Normal lung fibroblast cells treated with KU-55933, a specific ATM kinase inhibitor, showed increased numbers of exchanges at a dose of 1 Gy and higher, but were similar to wild type cells at 0.5 Gy or below. These results were confirmed using siRNA knockdown of ATM. The present study provides evidence that the increased radiation sensitivity of AT cells for chromosomal exchanges found at high dose does not occur at low dose.

  17. Classification of blood cells and tumor cells using label-free ultrasound and photoacoustics.

    Science.gov (United States)

    Strohm, Eric M; Kolios, Michael C

    2015-08-01

    A label-free method that can identify cells in a blood sample using high frequency photoacoustic and ultrasound signals is demonstrated. When the wavelength of the ultrasound or photoacoustic wave is similar to the size of a single cell (frequencies of 100-500 MHz), unique periodic features occur within the ultrasound and photoacoustic power spectrum that depend on the cell size, structure, and morphology. These spectral features can be used to identify different cell types present in blood, such as red blood cells (RBCs), white blood cells (WBCs), and circulating tumor cells. Circulating melanoma cells are ideal for photoacoustic detection due to their endogenous optical absorption properties. Using a 532 nm pulsed laser and a 375 MHz transducer, the ultrasound and photoacoustic signals from RBCs, WBCs, and melanoma cells were individually measured in an acoustic microscope to examine how the signals change between cell types. A photoacoustic and ultrasound signal was detected from RBCs and melanoma cells; only an ultrasound signal was detected from WBCs. The different cell types were distinctly separated using the ultrasound and photoacoustic signal amplitude and power spectral periodicity. The size of each cell was also estimated from the spectral periodicity. For the first time, sound waves generated using pulse-echo ultrasound and photoacoustics have been used to identify and size single cells, with applications toward counting and identifying cells, including circulating melanoma cells. © 2015 International Society for Advancement of Cytometry.

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

    International Nuclear Information System (INIS)

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

    2013-01-01

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

  19. White blood cell counting analysis of blood smear images using various segmentation strategies

    Science.gov (United States)

    Safuan, Syadia Nabilah Mohd; Tomari, Razali; Zakaria, Wan Nurshazwani Wan; Othman, Nurmiza

    2017-09-01

    In white blood cell (WBC) diagnosis, the most crucial measurement parameter is the WBC counting. Such information is widely used to evaluate the effectiveness of cancer therapy and to diagnose several hidden infection within human body. The current practice of manual WBC counting is laborious and a very subjective assessment which leads to the invention of computer aided system (CAS) with rigorous image processing solution. In the CAS counting work, segmentation is the crucial step to ensure the accuracy of the counted cell. The optimal segmentation strategy that can work under various blood smeared image acquisition conditions is remain a great challenge. In this paper, a comparison between different segmentation methods based on color space analysis to get the best counting outcome is elaborated. Initially, color space correction is applied to the original blood smeared image to standardize the image color intensity level. Next, white blood cell segmentation is performed by using combination of several color analysis subtraction which are RGB, CMYK and HSV, and Otsu thresholding. Noises and unwanted regions that present after the segmentation process is eliminated by applying a combination of morphological and Connected Component Labelling (CCL) filter. Eventually, Circle Hough Transform (CHT) method is applied to the segmented image to estimate the number of WBC including the one under the clump region. From the experiment, it is found that G-S yields the best performance.

  20. Red Blood Cell Parameters as Indices of Susceptibility to ...

    African Journals Online (AJOL)

    The anaemia recorded in infected cattle by 38 days post-infection (pi) was mildest in WF and most severe in SG. It was concluded that low red blood cell values (PCV, Hb and RBC) are some of the markers that are consistently associated with susceptibility of cattle to trypanosomosis. Of the three cattle breeds studied, the ...

  1. Automated counting of white blood cells in synovial fluid.

    NARCIS (Netherlands)

    R. de Jonge (Robert); R.W. Brouwer (Reinoud); M. Smit (Marij); M. de Frankrijker-Merkestijn; R.J. Dolhain; J.M.W. Hazes (Mieke); A.W. van Toorenenbergen (Albert); J. Lindemans (Jan)

    2004-01-01

    textabstractOBJECTIVES: To evaluate the performance of automated leucocyte (white blood cell; WBC) counting by comparison with manual counting. METHODS: The number of WBC was determined in heparinized synovial fluid samples by the use of (i) a standard urine cytometer (Kova) and a

  2. effects of septrin administration on blood cells parameters in humans

    African Journals Online (AJOL)

    honey

    2014-03-31

    Mar 31, 2014 ... RESEARCH PAPER. EFFECTS OF SEPTRIN ADMINISTRATION ON BLOOD CELLS PARAMETERS IN. HUMANS. *1Onyebuagu P.C., 2Kiridi K. and 1Pughikumo D.T.. 1Department of Human Physiology, Niger Delta University, Bayelsa, Nigeria. 2Department of Radiology, Niger. Delta University, Bayelsa ...

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

    DEFF Research Database (Denmark)

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

    2012-01-01

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

  4. Sorting of White Blood Cells in a Lattice

    Science.gov (United States)

    Carlson, Robert; Chan, Shirley; Gabel, Chris; Austin, Robert

    1997-03-01

    White blood cells represent a heterogenous population of differentially sticky and deformable objects. We examine here experiemnts where the hydrodynamic flow of such a population in a lattice of obstacles results in the fractionation of the objects, and will present modeling of the observed fractionation of the objects.

  5. Manipulation of microparticles and red blood cells using ...

    Indian Academy of Sciences (India)

    2014-02-13

    Feb 13, 2014 ... Home; Journals; Pramana – Journal of Physics; Volume 82; Issue 2. Manipulation of microparticles and red blood cells using optoelectronic tweezers ... We report the development of an optoelectronic tweezers set-up which works by lightinduced dielectrophoresis mechanism to manipulate microparticles.

  6. Correlation between Malaria and the Red Blood Cell Indices of ...

    African Journals Online (AJOL)

    This study was designed to determine the level of malaria endemicity and correlate between malaria parasitaemia and the red blood cell indices of the pregnant women in the Buea and Tiko health districts of the south west region of Cameroon. Samples were drawn from: The CDC Central Clinic Tiko, the Mutengene Baptist ...

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

    NARCIS (Netherlands)

    Hogman, CF; Meryman, HT

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

  8. Prolonged storage of red blood cells affects aminophospholipid translocase activity

    NARCIS (Netherlands)

    Verhoeven, A. J.; Hilarius, P. M.; Dekkers, D. W. C.; Lagerberg, J. W. M.; de Korte, D.

    2006-01-01

    BACKGROUND AND OBJECTIVES: Loss of phospholipid asymmetry in the membrane of red blood cells (RBC) results in exposure of phosphatidylserine (PS) and to subsequent removal from the circulation. In this study, we investigated the effect of long-term storage of RBCs on two activities affecting

  9. Assessment of Red Blood Cell Parameters and Peripheral Smear at ...

    African Journals Online (AJOL)

    Cold agglutination disease (CAD) is characterized by an auto‑antibody which is able to agglutinate red blood cells (RBCs) at temperatures lower than that of the body, and subsequently to activate the complement system responsible for lysis of RBCs. Patients show hemolytic anemia of varying degrees of severity, which ...

  10. Use of hydroxyethyl starch for inducing red blood cell aggregation

    NARCIS (Netherlands)

    Henkelman, Sandra; Rakhorst, Gerhard; van der Mei, Henny C.; Busscher, Henk J.

    2012-01-01

    Aggregation of human red blood cells (RBC) remains of biological and clinical interest. Replacement of plasma proteins by polymers to induce RBC aggregation may help to unravel the fundamentals of the aggregation process. Two theories exist to explain RBC aggregation mechanisms: a depletion and a

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

    African Journals Online (AJOL)

    The present work aims to evaluate the impact of potassium dichromate in armored catfishes' (Hypostomus plecotomus) erythropoiesis, using piscine micronucleus test. Armored catfishes (n = 30) were subjected to 12 mg/L of potassium dichromate, with an equal control group (n = 30). For each 2,000 red blood cells of ...

  12. Vascular Cell Senescence Contributes to Blood-Brain Barrier Breakdown

    NARCIS (Netherlands)

    Yamazaki, Y.; Baker, D.J.; Tachibana, M.; Liu, C.C.; Deursen, J.M.A. van; Brott, T.G.; Bu, G.; Kanekiyo, T.

    2016-01-01

    BACKGROUND AND PURPOSE: Age-related changes in the cerebrovasculature, including blood-brain barrier (BBB) disruption, are emerging as potential risks for diverse neurological conditions. Because the accumulation of senescent cells in tissues is increasingly recognized as a critical step leading to

  13. Diet induced gene expression in rat peripheral blood mononuclear cells

    NARCIS (Netherlands)

    Caimari, A.; Oliver, P.; Rodenburg, W.; Keijer, Jaap; Palou, A.

    2009-01-01

    Gene expression of rat peripheral blood mononuclear cells was analyzed by microarray analysis in normoweight and in diet-induced obese rats (cafeteria rats). The aim of this study was to identify genes involved in energy homeostasis that are altered in the obese state.

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

    Science.gov (United States)

    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.

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

    NARCIS (Netherlands)

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

    2011-01-01

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

  16. Characteristic point algorithm in laser ektacytometry of red blood cells

    Science.gov (United States)

    Nikitin, S. Yu.; Ustinov, V. D.

    2018-01-01

    We consider the problem of measuring red blood cell deformability by laser diffractometry in shear flow (ektacytometry). A new equation is derived that relates the parameters of the diffraction pattern to the width of the erythrocyte deformability distribution. The numerical simulation method shows that this equation provides a higher accuracy of measurements in comparison with the analogous equation obtained by us earlier.

  17. Whole-blood leukoreduction filters are a source for cryopreserved cells for phenotypic and functional investigations on peripheral blood lymphocytes.

    Science.gov (United States)

    Néron, Sonia; Dussault, Nathalie; Racine, Claudia

    2006-04-01

    Leukoreduction of blood is now widely performed by blood banks, and the possibility of recovering 10(8) to 10(9) white blood cells (WBCs) from leukoreduction filters, which are usually discarded, represents a promising source for normal human cells. Previous studies with these filters to prepare WBCs have performed their experimentation with fresh cells only. Whether these filter-derived cells could also be used to prepare frozen cell banks to facilitate work organization and open new avenues for their utilization as references in physiological studies and clinical investigations was investigated. Blood samples or whole-blood leukoreduction filters were obtained, after informed consent, from volunteers or blood donors, respectively. The proportions of CD3+, CD14+, CD16+, CD19+, and CD45+ cells within peripheral blood mononuclear cells (PBMNCs) were determined by flow cytometry from all samples. B cells were isolated and their functional responses were evaluated in vitro. The yield of PBMNCs recovered from whole-blood leukoreduction filters was lower (50%) than the one with fresh blood samples but still provided 2 x 10(8) to 4 x 10(8) PBMNCs per unit. After one cycle of freezing-thawing, the proportions of B- and T-cell populations were similar to normal blood values. Purified B cells issued from whole-blood leukoreduction filters displayed normal phenotypes and functions. Leukoreduction filters represent a valuable source of PBMNCs. These cells could be easily recovered to prepare frozen cell banks useful in basic phenotypic and functional analyses involving the main subsets of B cells and the global T-cell population.

  18. Cellular function reinstitution of offspring red blood cells cloned from the sickle cell disease patient blood post CRISPR genome editing.

    Science.gov (United States)

    Wen, Jianguo; Tao, Wenjing; Hao, Suyang; Zu, Youli

    2017-06-13

    Sickle cell disease (SCD) is a disorder of red blood cells (RBCs) expressing abnormal hemoglobin-S (HbS) due to genetic inheritance of homologous HbS gene. However, people with the sickle cell trait (SCT) carry a single allele of HbS and do not usually suffer from SCD symptoms, thus providing a rationale to treat SCD. To validate gene therapy potential, hematopoietic stem cells were isolated from the SCD patient blood and treated with CRISPR/Cas9 approach. To precisely dissect genome-editing effects, erythroid progenitor cells were cloned from single colonies of CRISPR-treated cells and then expanded for simultaneous gene, protein, and cellular function studies. Genotyping and sequencing analysis revealed that the genome-edited erythroid progenitor colonies were converted to SCT genotype from SCD genotype. HPLC protein assays confirmed reinstallation of normal hemoglobin at a similar level with HbS in the cloned genome-edited erythroid progenitor cells. For cell function evaluation, in vitro RBC differentiation of the cloned erythroid progenitor cells was induced. As expected, cell sickling assays indicated function reinstitution of the genome-edited offspring SCD RBCs, which became more resistant to sickling under hypoxia condition. This study is an exploration of genome editing of SCD HSPCs.

  19. Cellular function reinstitution of offspring red blood cells cloned from the sickle cell disease patient blood post CRISPR genome editing

    Directory of Open Access Journals (Sweden)

    Jianguo Wen

    2017-06-01

    Full Text Available Abstract Background Sickle cell disease (SCD is a disorder of red blood cells (RBCs expressing abnormal hemoglobin-S (HbS due to genetic inheritance of homologous HbS gene. However, people with the sickle cell trait (SCT carry a single allele of HbS and do not usually suffer from SCD symptoms, thus providing a rationale to treat SCD. Methods To validate gene therapy potential, hematopoietic stem cells were isolated from the SCD patient blood and treated with CRISPR/Cas9 approach. To precisely dissect genome-editing effects, erythroid progenitor cells were cloned from single colonies of CRISPR-treated cells and then expanded for simultaneous gene, protein, and cellular function studies. Results Genotyping and sequencing analysis revealed that the genome-edited erythroid progenitor colonies were converted to SCT genotype from SCD genotype. HPLC protein assays confirmed reinstallation of normal hemoglobin at a similar level with HbS in the cloned genome-edited erythroid progenitor cells. For cell function evaluation, in vitro RBC differentiation of the cloned erythroid progenitor cells was induced. As expected, cell sickling assays indicated function reinstitution of the genome-edited offspring SCD RBCs, which became more resistant to sickling under hypoxia condition. Conclusions This study is an exploration of genome editing of SCD HSPCs.

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

    Science.gov (United States)

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

    2017-03-01

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

  1. The in-vitro study of human blood leukemic cells by pulsed NMR

    International Nuclear Information System (INIS)

    Zulkarnaen, M.; Munawir; Wibowo, Tono; Suyitno, Gogot

    1983-01-01

    The diagram of leukemic cells in human blood has been studied by using the NMR longitudinal relaxation technique. The observation was treated in whole blood, serum and blood cell. Every result was compared with previous observation and show that the values of the proton longitudinal relaxation in the leukemic whole blood almost twice or more that of normal blood, while in the serum and the blood cell, the values are nearly the same. (author)

  2. Blood transfusions for treating acute chest syndrome in people with sickle cell disease.

    Science.gov (United States)

    Dastgiri, Saeed; Dolatkhah, Roya

    2016-08-30

    Sickle cell disease is an inherited autosomal recessive blood condition and is one of the most prevalent genetic blood diseases worldwide. Acute chest syndrome is a frequent complication of sickle cell disease, as well as a major cause of morbidity and the greatest single cause of mortality in children with sickle cell disease. Standard treatment may include intravenous hydration, oxygen as treatment for hypoxia, antibiotics to treat the infectious cause and blood transfusions may be given. This is an update of a Cochrane review first published in 2010. To assess the effectiveness of blood transfusions, simple and exchange, for treating acute chest syndrome by comparing improvement in symptoms and clinical outcomes against standard care. We searched The Cochrane Cystic Fibrosis and Genetic Disorders Group's Haemoglobinopathies Trials Register, which comprises references identified from comprehensive electronic database searches and handsearching of relevant journals and abstract books of conference proceedings.Date of the most recent search: 25 April 2016. Randomised controlled trials and quasi-randomised controlled trials comparing either simple or exchange transfusion versus standard care (no transfusion) in people with sickle cell disease suffering from acute chest syndrome. Both authors independently selected trials and assessed the risk of bias, no data could be extracted. One trial was eligible for inclusion in the review. While in the multicentre trial 237 people were enrolled (169 SCC, 42 SC, 15 Sβ⁰-thalassemia, 11Sβ(+)-thalassemia); the majority were recruited to an observational arm and only ten participants met the inclusion criteria for randomisation. Of these, four were randomised to the transfusion arm and received a single transfusion of 7 to 13 ml/kg packed red blood cells, and six were randomised to standard care. None of the four participants who received packed red blood cells developed acute chest syndrome, while 33% (two participants

  3. Cell contact-dependent outer membrane exchange in myxobacteria: genetic determinants and mechanism.

    Directory of Open Access Journals (Sweden)

    Darshankumar T Pathak

    Full Text Available Biofilms are dense microbial communities. Although widely distributed and medically important, how biofilm cells interact with one another is poorly understood. Recently, we described a novel process whereby myxobacterial biofilm cells exchange their outer membrane (OM lipoproteins. For the first time we report here the identification of two host proteins, TraAB, required for transfer. These proteins are predicted to localize in the cell envelope; and TraA encodes a distant PA14 lectin-like domain, a cysteine-rich tandem repeat region, and a putative C-terminal protein sorting tag named MYXO-CTERM, while TraB encodes an OmpA-like domain. Importantly, TraAB are required in donors and recipients, suggesting bidirectional transfer. By use of a lipophilic fluorescent dye, we also discovered that OM lipids are exchanged. Similar to lipoproteins, dye transfer requires TraAB function, gliding motility and a structured biofilm. Importantly, OM exchange was found to regulate swarming and development behaviors, suggesting a new role in cell-cell communication. A working model proposes TraA is a cell surface receptor that mediates cell-cell adhesion for OM fusion, in which lipoproteins/lipids are transferred by lateral diffusion. We further hypothesize that cell contact-dependent exchange helps myxobacteria to coordinate their social behaviors.

  4. [Ion-exchange properties of cell walls of red seaweed Phyllophora crispa].

    Science.gov (United States)

    Meĭchik, N R; Popova, N I; Nikolaeva, Iu I; Ermakov, I P; Kamnev, A N

    2011-01-01

    Research into ion-exchange properties of cell walls isolated from thallus of red seaweed Phyllophora crispa was carried out. Ion-exchange capacity and the swelling coefficient of the red alga cell walls were estimated at various pH values (from 2 to 12) and at constant ionic strength of a solution (10 mM). It was established that behavior of cell walls as ion-exchangers is caused by the presence in their matrix of two types of cation-exchange groups and amino groups. The amount of the functional group of each type was estimated, and the corresponding values of pK(a) were calculated. It can be assumed that ionogenic groups with pK(a) -5 are carboxyl groups of uronic acids, and ionogenic groups with pK(a) -7.5 are carboxyl groups of the proteins. Intervals of pH in which cation-exchange groups are ionized and can take part in exchange reactions with cations in the environment are defined. It was found that protein was a major component of cell wall polymeric matrix because its content was 36%.

  5. Red blood cell phenotype prevalence in blood donors who self-identify as Hispanic

    DEFF Research Database (Denmark)

    Sheppard, Chelsea A; Bolen, Nicole L; Eades, Beth

    2017-01-01

    CONCLUSIONS: Molecular genotyping platforms provide a quick, high-throughput method for identifying red blood cell units for patients on extended phenotype-matching protocols, such as those with sickle cell disease or thalassemia. Most of the antigen prevalence data reported are for non-Hispanic ......CONCLUSIONS: Molecular genotyping platforms provide a quick, high-throughput method for identifying red blood cell units for patients on extended phenotype-matching protocols, such as those with sickle cell disease or thalassemia. Most of the antigen prevalence data reported are for non......-Hispanic populations. Therefore, this study sought to determine the phenotype prevalence in a single blood center's Hispanic population and to compare those results with previously reported rates in non-Hispanic donor populations. We performed a retrospective review of all serologic and molecular typing from donors....... The most prevalent probable Rh phenotypes were R1r (26.6%), R1R2 (21.5%), and R1R1 (20.7%); rr was found in 7.8 percent of donors tested. The percentage of K+ donors in this population was 2.8 percent. The most prevalent Duffy phenotypes were Fy(a+b+) (35.9%), Fy(a+b-) (35.6%), and Fy(a-b+) (27...

  6. Long-term corneal endothelial cell changes in pediatric intraocular lens reposition and exchange cases.

    Science.gov (United States)

    Wang, Yan; Wu, Mingxing; Zhu, Liyuan; Liu, Yizhi

    2012-04-01

    To evaluate long-term corneal endothelial cell changes of intraocular lens (IOL) reposition and exchange in children. State key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, 510060, China In this retrospective study, all IOL reposition and exchange procedures performed in patients under 14 years old between January 1999 and April 2009 were included. Follow-up outcomes included corneal endothelial cell density, hexagonality, coefficient of variance, average cell size. IOL reposition procedures in 12 eyes (12 cases) (reposition group, RPG), and IOL exchanges in eight eyes (eight cases) (exchange group, EXG) were performed because of IOL pupillary capture or IOL dislocation. Median of follow-up was 44.5 months in RPG and 66.2 months in EXG. The density of corneal endothelial cells in RPG (2,053 ± 493/mm(2)) and EXG (2,100 ± 758/mm(2)) was significantly decreased in comparison to the control eyes (3,116 ± 335/mm(2)). Hexagonality of corneal endothelial cells and coefficient of variance showed no difference among the control group, RPG and EXG (P > 0.05). The density of corneal endothelial cells was conspicuously decreased after IOL reposition or exchange procedures in childhood cases. Longer follow-up must be conducted in these cases.

  7. Blood on the tracks: hematopoietic stem cell-endothelial cell interactions in homing and engraftment.

    Science.gov (United States)

    Perlin, Julie R; Sporrij, Audrey; Zon, Leonard I

    2017-08-01

    Cells of the hematopoietic system undergo rapid turnover. Each day, humans require the production of about one hundred billion new blood cells for proper function. Hematopoietic stem cells (HSCs) are rare cells that reside in specialized niches and are required throughout life to produce specific progenitor cells that will replenish all blood lineages. There is, however, an incomplete understanding of the molecular and physical properties that regulate HSC migration, homing, engraftment, and maintenance in the niche. Endothelial cells (ECs) are intimately associated with HSCs throughout the life of the stem cell, from the specialized endothelial cells that give rise to HSCs, to the perivascular niche endothelial cells that regulate HSC homeostasis. Recent studies have dissected the unique molecular and physical properties of the endothelial cells in the HSC vascular niche and their role in HSC biology, which may be manipulated to enhance hematopoietic stem cell transplantation therapies.

  8. A Framework for White Blood Cell Segmentation in Microscopic Blood Images Using Digital Image Processing

    Science.gov (United States)

    2009-01-01

    Evaluation of blood smear is a commonly clinical test these days. Most of the time, the hematologists are interested on white blood cells (WBCs) only. Digital image processing techniques can help them in their analysis and diagnosis. For example, disease like acute leukemia is detected based on the amount and condition of the WBC. The main objective of this paper is to segment the WBC to its two dominant elements: nucleus and cytoplasm. The segmentation is conducted using a proposed segmentation framework that consists of an integration of several digital image processing algorithms. Twenty microscopic blood images were tested, and the proposed framework managed to obtain 92% accuracy for nucleus segmentation and 78% for cytoplasm segmentation. The results indicate that the proposed framework is able to extract the nucleus and cytoplasm region in a WBC image sample. PMID:19517206

  9. ABO blood group mismatched hematopoietic stem cell transplantation.

    Science.gov (United States)

    Tekgündüz, Sibel Akpınar; Özbek, Namık

    2016-02-01

    Apart from solid organ transplantations, use of ABO-blood group mismatched (ABO-mismatched) donors is acceptable in hematopoietic stem cell transplantation (HSCT) patients. About 20-40% of allogeneic HSCT recipients will receive grafts from ABO-mismatched donors. ABO incompatible HSCT procedures are associated with immediate and late consequences, including but not restricted to acute or delayed hemolytic reactions, delayed red blood cell recovery, pure red cell aplasia and graft-versus-host disease. This review summarizes the current knowledge about consequences of ABO-mismatched HSCT in terms of associated complications and will evaluate its impact on important outcome parameters of HSCT. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Current state of the art of blood cell labeling

    International Nuclear Information System (INIS)

    Srivastava, S.C.; Straub, R.F.; Meinken, G.E.; Gil, M.C.

    1985-01-01

    An update on some recent developments in the area of blood cell labeling is provided. Specific topics covered include red cell labeling with /sup 99m/Tc, platelet labeling using an antiplatelet monoclonal antibody, and the labeling of leukocytes with /sup 99m/Tc. Mechanistic information, where available, is discussed. A critical evaluation of current techniques, their pitfalls as well as advantages, and the problems that remain to be resolved, is presented. The promise shown by recent results using the antibody approach for cell labeling is emphasized. An assessment of the progress made in these areas is presented. 38 refs., 10 figs., 6 tabs

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

    Science.gov (United States)

    Peng, Zhangli; Lu, Huijie

    2016-11-01

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

  12. Hemoglobin Variants Acquired Post-Exchange Transfusion in Pediatric Sickle Cell Disease (SCD) Patients.

    Science.gov (United States)

    Pandey, Soumya; Cottler-Fox, Michele; Drobena, Gina

    2015-01-01

    Many SCD patients receive chronic transfusions for prevention or treatment of disease related complications. Complications of the chronic transfusion noted in these patients include allergic reactions, transfusion transmitted infections, iron overload, and alloantibody formation. Even though hemoglobin (Hb) variants are prevalent in the general population, reports of transfusion-acquired Hb variants are rare. We performed a retrospective analysis on all SCD patients who underwent red cell exchange (RBCEx) transfusions at our institution during 2011-2013 to identify the presence of Hb variants acquired as a result of RBCEx. We found 66 occurrences of acquired Hb variants in 30 SCD patients during the period examined. The most commonly acquired Hb variant was Hemoglobin C (HbC) (64/66 occurrences). More than half of the patients (19/30) acquired HbC on multiple occasions (2-6 times). One patient acquired HbJ and another patient acquired HbD/G in addition to HbC. The segments from donor units were available in some of these cases and hemoglobin electrophoresis (HBE) was performed to confirm the presence of the variant Hb in the donor segments corresponding to that seen on the post-RBCEx sample. Heterozygous donors are asymptomatic and show no abnormalities during donor screening. Since HBE is not routinely performed on the donor specimen, it may go unrecognized until the post-transfusion recipient results pose diagnostic difficulties. There are no definitive guidelines on deferring these donors; hence one should be cognizant of these findings to prevent misdiagnosis. In a population where HbS negative blood is routinely requested, the effect of other Hb variants remains unknown. None of the patients in our study showed any adverse events due to the acquired Hb variants; however, this is of special concern in the pediatric population where a single RBC unit can contribute a significant portion of the exchanged blood volume. Additionally, donor centers may need

  13. Saccharin-induced sister chromatid exchanges in Chinese hamster and human cells

    Energy Technology Data Exchange (ETDEWEB)

    Wolff, S.; Rodin, B.

    1978-05-05

    Since the induction of sister chromatid exchanges in cultured cells has been shown to be the most sensitive mammalian system to detect the effects of mutagenic carcinogens, Chinese hamster ovary cells and human lymphocytes were exposed to the sodium saccharin found to induce bladder cancer in rats. Both that saccharin and a highly purified extract of it increased the yield of sister chromatid exchanges in both types of cells. The results, which were repeatable and statistically highly significant, indicated that the weak carcinogen, saccharin, is also mutagenic in the sense that it induces cytogenetic changes.

  14. Method of detecting defects in ion exchange membranes of electrochemical cells by chemochromic sensors

    Science.gov (United States)

    Brooker, Robert Paul; Mohajeri, Nahid

    2016-01-05

    A method of detecting defects in membranes such as ion exchange membranes of electrochemical cells. The electrochemical cell includes an assembly having an anode side and a cathode side with the ion exchange membrane in between. In a configuration step a chemochromic sensor is placed above the cathode and flow isolation hardware lateral to the ion exchange membrane which prevents a flow of hydrogen (H.sub.2) between the cathode and anode side. The anode side is exposed to a first reactant fluid including hydrogen. The chemochromic sensor is examined after the exposing for a color change. A color change evidences the ion exchange membrane has at least one defect that permits H.sub.2 transmission therethrough.

  15. Cholesterol metabolism in blood cells of irradiated rats

    International Nuclear Information System (INIS)

    Novoselova, E.G.; Kulagina, T.P.; Potekhina, N.I.

    1985-01-01

    Cholesterol metabolism in blood erythrocytes and lymphocytes of irradiated rats has been investigated. It has been found that at all terms and doses of irradiation, a suppression of the synthesis of erythrocyte cholesterol is observed. The increase of cholesterol quantiy in erythrocytes upon total gamma irradiation in the 10 Gr dose possibly is the result of growth of cholesterol transfer from plasma into erythrocyte cells. The study of the cholesterol synthesis in suspension of lymphocytes elminated from peripheral blood of control and irradiated rats has shown that at irradiation doses of 4 and 10 Gr in an hour acivation of cholesterol synthesis in vitro takes places

  16. Low stoichiometry operation of a proton exchange membrane fuel cell employing the interdigitated flow field

    DEFF Research Database (Denmark)

    Berning, Torsten; Kær, Søren Knudsen

    2012-01-01

    A multiphase fuel cell model based on computational fluid dynamics is used to investigate the possibility of operating a proton exchange membrane fuel cell at low stoichiometric flow ratios (ξ < 1.5) employing the interdigitated flow field design and using completely dry inlet gases. A case study...

  17. The measurement of limb blood flow using technetium-labelled red blood cells

    International Nuclear Information System (INIS)

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

    1986-01-01

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

  18. A cell transportation solution that preserves live circulating tumor cells in patient blood samples.

    Science.gov (United States)

    Stefansson, Steingrimur; Adams, Daniel L; Ershler, William B; Le, Huyen; Ho, David H

    2016-05-06

    Circulating tumor cells (CTCs) are typically collected into CellSave fixative tubes, which kills the cells, but preserves their morphology. Currently, the clinical utility of CTCs is mostly limited to their enumeration. More detailed investigation of CTC biology can be performed on live cells, but obtaining live CTCs is technically challenging, requiring blood collection into biocompatible solutions and rapid isolation which limits transportation options. To overcome the instability of CTCs, we formulated a sugar based cell transportation solution (SBTS) that stabilizes cell viability at ambient temperature. In this study we examined the long term viability of human cancer cell lines, primary cells and CTCs in human blood samples in the SBTS for transportation purposes. Four cell lines, 5 primary human cells and purified human PBMCs were tested to determine the viability of cells stored in the transportation solution at ambient temperature for up to 7 days. We then demonstrated viability of MCF-7 cells spiked into normal blood with SBTS and stored for up to 7 days. A pilot study was then run on blood samples from 3 patients with metastatic malignancies stored with or without SBTS for 6 days. CTCs were then purified by Ficoll separation/microfilter isolation and identified using CTC markers. Cell viability was assessed using trypan blue or CellTracker™ live cell stain. Our results suggest that primary/immortalized cell lines stored in SBTS remain ~90% viable for > 72 h. Further, MCF-7 cells spiked into whole blood remain viable when stored with SBTS for up to 7 days. Finally, live CTCs were isolated from cancer patient blood samples kept in SBTS at ambient temperature for 6 days. No CTCs were isolated from blood samples stored without SBTS. In this proof of principle pilot study we show that viability of cell lines is preserved for days using SBTS. Further, this solution can be used to store patient derived blood samples for eventual isolation of viable CTCs after

  19. Studies on ADCC (antibody-dependent cell-mediated cytotoxicity) using sheep red blood cells as target cells, 2

    International Nuclear Information System (INIS)

    Ichikawa, Yukinobu; Takaya, Masatoshi; Arimori, Shigeru

    1979-01-01

    A non-specific cytotoxic mediator from effector cells (human peripheral blood leukocytes) was investigated in the ADCC (antibody-dependent cell-mediated cytotoxicity) system using antibody-coated sheep red blood cells (SRBC) as target cells. 51 Cr-labelled homologous (sheep) or heterologous (human) red blood cells were used as adjacent cells. Either crude lymphocyte fraction, phagocyte depleted fraction or granulocyte rich fraction separated from human peripheral leukocytes showed moderate cytotoxic effect on homologous adjacent cells, however no cytotoxic activity on heterologous adjacent cells was demonstrated in any leukocyte fraction. This suggests that the cytotoxic effects on homologous adjacent cells were resulted from the translocation of antibody molecules to adjacent cells from antibody-coated target cells. We concluded that the cytotoxic mechanism in this ADCC system was not mediated by non-specific soluble factors released from either human peripheral lymphocytes, monocytes or granulocytes. (author)

  20. The role of cell walls and pectins in cation exchange and surface area of plant roots.

    Science.gov (United States)

    Szatanik-Kloc, A; Szerement, J; Józefaciuk, G

    2017-08-01

    We aimed to assess role of cell walls in formation of cation exchange capacity, surface charge, surface acidity, specific surface, water adsorption energy and surface charge density of plant roots, and to find the input of the cell wall pectins to the above properties. Whole roots, isolated cell walls and the residue after the extraction of pectins from the cell walls of two Apiaceae L. species (celeriac and parsnip) were studied using potentiometric titration curves and water vapor adsorption - desorption isotherms. Total amount of surface charge, as well as the cation exchange capacity were markedly higher in roots than in their cell walls, suggesting large contribution of other cell organelles to the binding of cations by the whole root cells. Significantly lower charge of the residues after removal of pectins was noted indicating that pectins play the most important role in surface charge formation of cell walls. The specific surface was similar for all of the studied materials. For the separated cell walls it was around 10% smaller than of the whole roots, and it increased slightly after the removal of pectins. The surface charge density and water vapor adsorption energy were the highest for the whole roots and the lowest for the cell walls residues after removal of pectins. The results indicate that the cell walls and plasma membranes are jointly involved in root ion exchange and surface characteristics and their contribution depends upon the plant species. Copyright © 2017 Elsevier GmbH. All rights reserved.

  1. Advances in fuel cells of proton exchange membrane (PEMSFCs)

    International Nuclear Information System (INIS)

    Delgado Avila, Graciela

    2008-01-01

    Growing demand of energy sources exempt from pollutant substances and that are efficient for domestic, industrial applications and in vehicles, this has propitiated that at present the engineers are designing fuel cells out of the spatial agencies. These fuel cells have advantages such as: high energetic density of the H2, are not pollutant, are electrolytic permanent rechargeable cells with hydrogen; they have anodic reaction with oxygen of the air, and the existence of multiple hydrogen sources. The cells are constructed along the general lines of multiple cells connected in series by two-pole plates. A great effort is realized in the partial or total substitution of the Nafion, the catalyst (Pt) is scanty and is poisoned with CO. The cell has a high cost, but it is one of the most promising technologies to reduce the pollution and the gas emission. In addition, it favors the greenhouse effect [es

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

    Science.gov (United States)

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

    2016-04-01

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

  3. Thermal diversities of two Na+/H+ exchanges in guinea pig red cells.

    Science.gov (United States)

    Ji, H L

    2001-09-01

    To test the effect of hypothermia on Na+/H+ exchange, activated by shrinkage and cytoplasmic acidosis. Amiloride-sensitive Na+ influx in guinea pig red cells was traced with isotope 22Na and intracellular Na+ concentration was measured by emission flame photometry. Amiloride-sensitive Na+ influx decreased linearly as a function of temperatures (about 37 degrees C) in shrunken cells, but increased in acidified cells. The up-regulation of acid-induced Na+/H+ exchange by elevated temperature was enhanced by hypo-osmolarity. Less sensitivity of intracellular H+ site at 41 degrees C may be the mechanism for the inhibition of shrinkage-induced Na+/H+ exchange by elevated temperature. Heating-mediated explosive increase in the activity of acid-induced Na+/H+ exchange may be due to enhanced extracellular Na+ sensitivity and lower intracellular pH caused by acidic metabolites. Acid-induced Na+/H+ exchange contributes to cytoplasmic Na+ accumulation. These two modes of Na+/H+ exchange with different response to elevated temperature may play different roles in the cellular pathogenesis of heatstroke.

  4. Erythropoietic Potential of CD34+ Hematopoietic Stem Cells from Human Cord Blood and G-CSF-Mobilized Peripheral Blood

    Directory of Open Access Journals (Sweden)

    Honglian Jin

    2014-01-01

    Full Text Available Red blood cell (RBC supply for transfusion has been severely constrained by the limited availability of donor blood and the emergence of infection and contamination issues. Alternatively, hematopoietic stem cells (HSCs from human organs have been increasingly considered as safe and effective blood source. Several methods have been studied to obtain mature RBCs from CD34+ hematopoietic stem cells via in vitro culture. Among them, human cord blood (CB and granulocyte colony-stimulating factor-mobilized adult peripheral blood (mPB are common adult stem cells used for allogeneic transplantation. Our present study focuses on comparing CB- and mPB-derived stem cells in differentiation from CD34+ cells into mature RBCs. By using CD34+ cells from cord blood and G-CSF mobilized peripheral blood, we showed in vitro RBC generation of artificial red blood cells. Our results demonstrate that CB- and mPB-derived CD34+ hematopoietic stem cells have similar characteristics when cultured under the same conditions, but differ considerably with respect to expression levels of various genes and hemoglobin development. This study is the first to compare the characteristics of CB- and mPB-derived erythrocytes. The results support the idea that CB and mPB, despite some similarities, possess different erythropoietic potentials in in vitro culture systems.

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

    Directory of Open Access Journals (Sweden)

    Marco Marziali

    2014-08-01

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

  6. Cobalt uptake and binding in human red blood cells

    DEFF Research Database (Denmark)

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

    2011-01-01

    A23187 mediates a rapid equilibration of Co(2+) across the cell membrane leading to a marked accumulation, reflecting effective cytoplasmic buffering. The fraction (a(Co)) of total cell cobalt being present as free, ionized Co(2+) is estimated at a(Co)=0.01 from the equilibrium distribution...... reversibly bound, being releasable by excess extracellular EGTA in the presence of A23187, and partly tightly bound, remaining in the cells even at high ionophore concentrations. The tightly bound fraction builds up over time, and is larger and develops earlier in fed cells compared to ATP-depleted cells......, compared with timed or in-competition whole-blood and serum analysis, an average value for the exposure over the last couple of months....

  7. HIV-1 isolation from infected peripheral blood mononuclear cells.

    Science.gov (United States)

    Dispinseri, Stefania; Saba, Elisa; Vicenzi, Elisa; Kootstra, Neeltje A; Schuitemaker, Hanneke; Scarlatti, Gabriella

    2014-01-01

    Human immunodeficiency virus 1 (HIV-1) isolation from peripheral blood mononuclear cells (PBMCs) allows retrieval of replication-competent viral variants. In order to impose the smallest possible selective pressure on the viral isolates, isolation must be carried out in primary cultures of cells and not in tumor derived cell lines. The procedure involves culture of PBMCs from an infected patient with phytohemagglutinin (PHA)-stimulated PBMC from seronegative donors, which provide susceptible target cells for HIV replication. HIV can be isolated from the bulk population of PBMCs or after cloning of the cells to obtain viral biological clones. Viral production is determined with p24 antigen (Ag) detection assays or with reverse transcriptase (RT) activity assay. Once isolated, HIV-1 can be propagated by infecting PHA-stimulated PBMCs from healthy donors. Aliquots from culture with a high production of virus are stored for later use.

  8. FUEL CELL PROTON EXCHANGE MEMBRANE - PRESENT AND PERSPECTIVES

    Directory of Open Access Journals (Sweden)

    Victor CIUPINA

    2012-05-01

    Full Text Available The fuel cells could contribute to the reduction of the pollution emission and the fossil fuels due to the conversion efficiency which is higher than the other energy conversion systems. There are many possibilities to improve the efficiency and to reduce the weight of the fuel cells by the integration of new nanostructured materials.

  9. Hot topics in alkaline exchange membrane fuel cells

    Science.gov (United States)

    Serov, Alexey; Zenyuk, Iryna V.; Arges, Christopher G.; Chatenet, Marian

    2018-01-01

    The tremendous progress from the first discovery of fuel cell principles by Sir William Robert Grove in 1839 [1] and independent observation of electricity generated in electrochemical reaction of hydrogen and air by a Swiss scientist Christian F. Shoenbein [2] to the recent breakthroughs in the fuel cell field resulted in the appearance of this clean energy technology around us. Indeed, fuel cell technology undoubtedly has entered into our life with the first introduction of Toyota Mirai Fuel Cell Vehicle (FCV) by Toyota Motor Co. in December of 2014 [3,4]. This FCV is commercially available and can be purchased in several countries. However, its sticker price of 57,500 substantially limits the number of customers that can purchase it. There are numerous factors that contribute to the high cost of fuel cell stack, however the price of platinum and platinum alloys is the main contributor [5].

  10. Microfluidic device for rapid solution exchange to study kinetics of cell physiology

    Science.gov (United States)

    Hu, Howard; Honnatti, Meghana; Gillis, Kevin

    2006-11-01

    Exchanging the extracellular solution of the cell rapidly (less than 10ms) is an important requirement in study the kinetics of cell physiology. A microfluidic device is developed to exchange the solution around the cells as they flow through a junction at the intersection of two microfluidic channels. The solution exchange time is measured experimentally by fluorescently labeling the cell surface membranes with a styryl dye, FM1-43 or FM 2-10, and then observing the time course of cell fluorescence decay following the rapid drop in the extracellular concentration of the FM dye that occurs as the cell flows past the fluidic junction. A numerical model is developed to guide the experimental design of microfluidic device. In the model, the motion of a single cell through a fluid junction is simulated and the mixing process of the solutions is solved. The model also includes the kinetics of departitioning of FM dyes from the cell membrane. The departitioning time constants for the FM dyes are determined from fitting the measured data of the cell fluorescence decay. This departitioning kinetics is important as FM dyes are commonly used to label cell membranes for the purpose of measuring the release of neurotransmitter from synaptic vesicles via exocytosis and the subsequent reuptake of vesicular membrane by endocytosis.

  11. Harvesting, processing and inventory management of peripheral blood stem cells

    Directory of Open Access Journals (Sweden)

    Mijovic Aleksandar

    2007-01-01

    Full Text Available By 2003, 97% autologous transplants and 65% of allogeneic transplants in Europe used mobilised peripheral blood stem cells (PBSC. Soon after their introduction in the early 1990′s, PBSC were associated with faster haemopoietic recovery, fewer transfusions and antibiotic usage, and a shorter hospital stay. Furthermore, ease and convenience of PBSC collection made them more appealing than BM harvests. Improved survival has hitherto been demonstrated in patients with high risk AML and CML. However, the advantages of PBSC come at a price of a higher incidence of extensive chronic GVHD. In order to be present in the blood, stem cells undergo the process of "mobilisation" from their bone marrow habitat. Mobilisation, and its reciprocal process - homing - are regulated by a complex network of molecules on the surface of stem cells and stromal cells, and enzymes and cytokines released from granulocytes and osteoclasts. Knowledge of these mechanisms is beginning to be exploited for clinical purposes. In current practice, stem cell are mobilised by use of chemotherapy in conjunction with haemopoietic growth factors (HGF, or with HGF alone. Granulocyte colony stimulating factor has emerged as the single most important mobilising agent, due to its efficacy and a relative paucity of serious side effects. Over a decade of use in healthy donors has resulted in vast experience of optimal dosing and administration, and safety matters. PBSC harvesting can be performed on a variety of cell separators. Apheresis procedures are nowadays routine, but it is important to be well versed in the possible complications in order to avoid harm to the patient or donor. To ensure efficient collection, harvesting must begin when sufficient stem cells have been mobilised. A rapid, reliable, standardized blood test is essential to decide when to begin harvesting; currently, blood CD34+ cell counting by flow cytometry fulfils these criteria. Blood CD34+ cell counts strongly

  12. Reduction of prion infectivity in packed red blood cells

    International Nuclear Information System (INIS)

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

    2008-01-01

    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 Sc ) and infectivity from red blood cell (RBC) suspensions by a simple washing procedure using a cell separation and washing device. The extent of prion removal was assessed by Western blot, PMCA and infectivity bioassays. Our results revealed a substantial removal of infectious prions (≥3 logs of infectivity) by all techniques used. These data suggest that a significant amount of infectivity present in RBC preparations can be removed by a simple washing procedure. This technology may lead to increased safety of blood products and reduce the risk of further propagation of prion diseases.

  13. Aging: a portrait from gene expression profile in blood cells.

    Science.gov (United States)

    Calabria, Elisa; Mazza, Emilia Maria Cristina; Dyar, Kenneth Allen; Pogliaghi, Silvia; Bruseghini, Paolo; Morandi, Carlo; Salvagno, Gian Luca; Gelati, Matteo; Guidi, Gian Cesare; Bicciato, Silvio; Schiaffino, Stefano; Schena, Federico; Capelli, Carlo

    2016-08-01

    The availability of reliable biomarkers of aging is important not only to monitor the effect of interventions and predict the timing of pathologies associated with aging but also to understand the mechanisms and devise appropriate countermeasures. Blood cells provide an easily available tissue and gene expression profiles from whole blood samples appear to mirror disease states and some aspects of the aging process itself. We report here a microarray analysis of whole blood samples from two cohorts of healthy adult and elderly subjects, aged 43±3 and 68±4 years, respectively, to monitor gene expression changes in the initial phase of the senescence process. A number of significant changes were found in the elderly compared to the adult group, including decreased levels of transcripts coding for components of the mitochondrial respiratory chain, which correlate with a parallel decline in the maximum rate of oxygen consumption (VO2max), as monitored in the same subjects. In addition, blood cells show age-related changes in the expression of several markers of immunosenescence, inflammation and oxidative stress. These findings support the notion that the immune system has a major role in tissue homeostasis and repair, which appears to be impaired since early stages of the aging process.

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

    Science.gov (United States)

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

    2016-01-01

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

  15. Red cell properties after different modes of blood transportation

    Directory of Open Access Journals (Sweden)

    Asya Makhro

    2016-07-01

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

  16. Reprogramming of blood cells into induced pluripotent stem cells as a new cell source for cartilage repair.

    Science.gov (United States)

    Li, Yueying; Liu, Tie; Van Halm-Lutterodt, Nicholas; Chen, JiaYu; Su, Qingjun; Hai, Yong

    2016-02-17

    An attempt was made to reprogram peripheral blood cells into human induced pluripotent stem cell (hiPSCs) as a new cell source for cartilage repair. We generated chondrogenic lineage from human peripheral blood via hiPSCs using an integration-free method. Peripheral blood cells were either obtained from a human blood bank or freshly collected from volunteers. After transforming peripheral blood cells into iPSCs, the newly derived iPSCs were further characterized through karyotype analysis, pluripotency gene expression and cell differentiation ability. iPSCs were differentiated through multiple steps, including embryoid body formation, hiPSC-mesenchymal stem cell (MSC)-like cell expansion, and chondrogenic induction for 21 days. Chondrocyte phenotype was then assessed by morphological, histological and biochemical analysis, as well as the chondrogenic expression. hiPSCs derived from peripheral blood cells were successfully generated, and were characterized by fluorescent immunostaining of pluripotent markers and teratoma formation in vivo. Flow cytometric analysis showed that MSC markers CD73 and CD105 were present in monolayer cultured hiPSC-MSC-like cells. Both alcian blue and toluidine blue staining of hiPSC-MSC-chondrogenic pellets showed as positive. Immunohistochemistry of collagen II and X staining of the pellets were also positive. The sulfated glycosaminoglycan content was significantly increased, and the expression levels of the chondrogenic markers COL2, COL10, COL9 and AGGRECAN were significantly higher in chondrogenic pellets than in undifferentiated cells. These results indicated that peripheral blood cells could be a potential source for differentiation into chondrogenic lineage in vitro via generation of mesenchymal progenitor cells. This study supports the potential applications of utilizing peripheral blood cells in generating seed cells for cartilage regenerative medicine in a patient-specific and cost-effective approach.

  17. Exploring the relationship of peripheral total bilirubin, red blood cell, and hemoglobin with blood pressure during childhood and adolescence.

    Science.gov (United States)

    Chen, Xiao-Tian; Yang, Song; Yang, Ya-Ming; Zhao, Hai-Long; Chen, Yan-Chun; Zhao, Xiang-Hai; Wen, Jin-Bo; Tian, Yuan-Rui; Yan, Wei-Li; Shen, Chong

    2017-11-04

    Total bilirubin is beneficial for protecting cardiovascular diseases in adults. The authors aimed to investigate the association of total bilirubin, red blood cell, and hemoglobin levels with the prevalence of high blood pressure in children and adolescents. A total of 3776 students (aged from 6 to 16 years old) were examined using cluster sampling. Pre-high blood pressure and high blood pressure were respectively defined as the point of 90th and 95th percentiles based on the Fourth Report on the Diagnosis, Evaluation, and Treatment of High Blood Pressure in Children and Adolescents. Both systolic and diastolic blood pressure were standardized into z-scores. Peripheral total bilirubin, red blood cell and hemoglobin levels were significantly correlated with age, and also varied with gender. Peripheral total bilirubin was negatively correlated with systolic blood pressure in 6- and 9-year-old boys, whilst positively correlated with diastolic blood pressure in the 12-year-old boys and 13- to 15-year-old girls (p0.05). Total bilirubin could be weakly correlated with both systolic and diastolic blood pressure, as correlations varied with age and gender in children and adolescents; in turn, the increased levels of red blood cell and hemoglobin are proposed to be positively associated with the prevalence of high blood pressure. Copyright © 2017 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.

  18. Clinical applications of indium-111-acetylacetone-labelled blood cells

    International Nuclear Information System (INIS)

    Georgi, P.; Sinn, H.; Wellman, H.; Clorius, J.H.; Becker, W.

    1981-01-01

    A method permitting red-cell labelling with 111 In-acetylacetone was reported in 1974 for evaluating intestinal blood loss, the liver-spleen ratio and the red-cell volume. White blood cells can be tagged similarly. In white-cell labelling, simultaneous red-cell or platelet tagging is avoided. Several procedures (dextran separation and gradient centrifugations) have been combined, to develop a highly selective cell separation. In osteomyelitis it may not be as advantageous to use 67 Ga-citrate, as in inflammatory soft tissue processes. The detection of inflammatory processes with labelled leukocytes could be of great importance for the scintigraphic diagnosis of osteomyelitidies. A group of 97 patients with suspected osteomyelitis have been examined using 111 In-acetylacetone-labelled leukocytes ( 111 In-AAL) immediately following positive routine skeletal scintigraphy. Images obtained 24 h post injection usually were the most satisfactory. In the followup group of 70 patients 21 true positives, 43 true negatives, 21 false negatives and 3 false positives were observed. These findings result in a specificity of 92%, sensitivity of 50% and accuracy of 70% with 111 In-AAL for osteomyelitis. Preliminary investigations using 111 In-acetylacetone-labelled thrombocytes ( 111 In-AAT) were carried out to detect rejection of transplanted kidneys. The platelets were separated by means of additional special density gradient centrifugations but no dextran from 15-20 ml of autologous whole blood. Scans have been obtained 15 min, 2.5 h and 24 h post injection in an initial group of 10 patients. In acute rejection, a high transplant uptake has been detected, whereas patients without acute rejection showed no or only a minimum activity accumulation. Patients with chronic rejection have intermediate uptakes

  19. Shed-blood-separation and cell-saver

    DEFF Research Database (Denmark)

    Bauer, Adrian; Hausmann, Harald; Schaarschmidt, Jan

    2018-01-01

    OBJECTIVE: The postoperative systemic inflammatory response after cardiopulmonary bypass (CPB) is still an undesirable side-effect after cardiac surgery. It is most likely caused by blood contact with foreign surfaces and by the surgical trauma itself. However, the recirculation of activated shed...... of a cell-saver (TNF-α ng/l post-ECC 10 min: 9.5±3.5 vs. 19.7±14.5, p

  20. Stored red blood cell transfusions: iron, inflammation, immunity, and infection.

    Science.gov (United States)

    Spitalnik, Steven L

    2014-10-01

    Emily Cooley was a highly regarded medical technologist and morphologist. The "Emily Cooley Lectureship and Award" was established to honor her, in particular, and medical technologists, in general. This article reviews some basic concepts about the "life of a red blood cell" (RBC) and uses these to discuss the actual and potential consequences that occur in patients after clearance of transfused refrigerator storage-damaged RBCs by extravascular hemolysis. © 2014 AABB.

  1. Cesarean section imprints cord blood immune cell distributions

    DEFF Research Database (Denmark)

    Thysen, Anna Hammerich; Larsen, Jeppe Madura; Rasmussen, Mette Annelie

    2014-01-01

    Immune programming in early life may affect the risk of developing immune-related diseases later in life. Children born by cesarean section seem to be at higher risk of asthma, allergic rhinitis, and type-1 diabetes. We hypothesized that delivery by cesarean section may affect immune maturation...... in newborns. The objective of the study was to profile innate and adaptive immune cell subsets in cord blood of children born by cesarean section or natural birth....

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

    Science.gov (United States)

    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. Magnetic properties of tunicate blood cells. II. Ascidia ceratodes.

    Science.gov (United States)

    Kustin, K; Robinson, W E; Frankel, R B; Spartalian, K

    1996-08-15

    The magnetic properties of intact blood cells of the tunicate Ascidia ceratodes have been measured up to 50 kOe with a SQUID susceptometer. Analysis of total metal contents by plasma emission spectroscopy and V(IV) content by epr indicates that approximately 5% of the accumulated vanadium is +4 vanadyl ion. Measured values of the magnetic moment Mp at different values of the applied magnetic field H over the temperature range T = 2-100 K depend on the magnitude of the field indicating magnetic anisotropy of the ground state. The slope of the Mp vs. H/T curve at high temperature is significantly higher than expected from electron spin S = 1 per vanadium(III) ion. The model that fits these data best is a dimer with one V(III) S = 1 ion ferromagnetically coupled to a second V(III) S = 1 ion, with spin-coupling constant J = 3.5 cm-1, and 5% of the total vanadium content in the form of a V(IV) S = 1/2 ion. Since vanadium in A. ceratodes is known to reside in at least three different types of blood cell, the excellent fit indicates that the metal is stored predominantly as a dimer regardless of blood cell type. Ferromagnetic coupling implies that the two vanadium ions in the dimer are connected by an unprotonated mu-oxo bridge.

  4. Performance of proton exchange membrane fuel cells at elevated temperature

    International Nuclear Information System (INIS)

    Shyu, Jin-Cherng; Hsueh, Kan-Lin; Tsau, Fanghei

    2011-01-01

    Highlights: → At 1 atm, cell has best performance (∼1300 mA/cm at 0.6 V) at 100 deg. C and RH = 100%. → The A value in Eq. increased with increases in the back pressure and RH. →R i dramatically decreased at back pressure of 1 atm. → At each RH, R i decreased and then increased as cell temperature increased at 1 atm. - Abstract: The polarization curves of a single PEMFC having a Nafion membrane fed with H 2 /O 2 with relative humidity (RH) of 35%, 70% and 100% were measured at cell temperatures ranging from 65 deg. C to 120 deg. C at back pressures of 0 atm and 1 atm, respectively. Measured results showed that the best cell performance at 0.6 V operated within 65-120 deg. C at zero back pressure was 1000 mA cm -2 at 65 deg. C and RH = 100%, while the best cell performance at 1 atm back pressure was 1300 mA cm -2 at 100 deg. C and RH = 100%. Based on the analysis of impedance data measured at anode and cathode humidification temperatures of 90 deg. C and cell temperature of 100 deg. C at back pressures of 0 and 1 atm (90-100p0 and 90-100p1), it could be found that the membrane resistance was reduced and the catalyst became more active as the back pressure increases. The present results showed that increasing back pressure was able to dramatically improve cell performance and the effect of the back pressure surpassed that of humidification in the internal resistance of cell.

  5. Commercialization of proton exchange membrane (PEM) fuel cell technology

    International Nuclear Information System (INIS)

    Goel, N.; Pant, A.; Sera, G.

    1995-01-01

    The MCTTC performed a market assessment for PEM Fuel Cells for terrestrial applications for the Center for Space Power (CSP). The purpose of the market assessment was to gauge the market and commercial potential for PEM fuel cell technology. Further, the market assessment was divided into subsections of technical and market overview, competitive environment, political environment, barriers to market entry, and keys to market entry. The market assessment conducted by the MCTTC involved both secondary and primary research. The primary target markets for PEM fuel cells were transportation and utilities in the power range of 10 kW to 100 kW. The fuel cell vehicle market size was estimated under a pessimistic scenario and an optimistic scenario. The estimated size of the fuel cell vehicle market in dollar terms for the year 2005 is $17.3 billion for the pessimistic scenario and $34.7 billion for the optimistic scenario. The fundamental and applied research funded and conducted by the National Aeronautics and Space Administration (NASA) and DOE in the area of fuel cells presents an excellent opportunity to commercialize dual-use technology and enhance U.S. business competitiveness. copyright 1995 American Institute of Physics

  6. Model-based analysis of anion-exchanger positioning in direct methanol fuel cell systems

    Science.gov (United States)

    Kraus, Maik; Schröder, Daniel; Krewer, Ulrike

    2014-09-01

    In this work we present a model based study to investigate the presence of anion exchangers in direct methanol fuel cell (DMFC) systems. It is well known that environmental or fuel impurities lead to accumulation of harmful anions, such as chloride, in the system. However, due to DMFC anodic reaction, a carbonate system is present. These corbanate anions have to be taken into account for the anion exchanger design and placement as well as for the system operation strategy with and without anion exchanger, which is the objective of this study. For this purpose, the expected amount of harmful chloride ions in a DMFC system is estimated, and that of carbonate ions is calculated with a model of the carbonate system in a DMFC system. The predicition of durability and dimensions of an anion exchanger is based on a monovalent anion exchange model. The design of gas liquid separators in the DMFC system has a major influence on the amount of dissolved carbon dioxide, which is crucial for durability and dimension of a system integrated anion exchanger. Finally, feasible positions of anion exchanger in a DMFC system are elaborated to fulfill the needs for long term and stable DMFC operation.

  7. Online hydrogen/deuterium exchange performed in the ion mobility cell of a hybrid mass spectrometer.

    Science.gov (United States)

    Nagy, Kornél; Redeuil, Karine; Rezzi, Serge

    2009-11-15

    The present paper describes the performance of online, gas-phase hydrogen/deuterium exchange implemented in the ion mobility cell of a quadrupole time-of-flight mass spectrometer. Deuterium oxide and deuterated methanol were utilized to create deuterated vapor that is introduced into the ion mobility region of the mass spectrometer. Hydrogen/deuterium exchange occurs spontaneously in the milliseconds time frame without the need of switching the instrument into ion mobility mode. The exchange was studied in case of low molecular weight molecules and proteins. The observed number of exchanged hydrogens was equal to the number of theoretically exchangeable hydrogens for all low molecular weight compounds. This method needs only minimal instrumental modifications, is simple, cheap, environment friendly, compatible with ultraperformance liquid chromatography, and can be implemented on commercially available instruments. It does not compromise choice of liquid chromatographic solvents and accurate mass or parallel-fragmentation (MS(E)) methods. The performance of this method was compared to that of conventional alternatives where the deuterated solvent is introduced into the cone gas of the instrument. Although the degree of exchange was similar between the two methods, the "cone gas method" requires 10 times higher deuterated solvent volumes (50 muL/min) and offers reduced sensitivity in the tandem mass spectrometry (MS/MS) mode. The presented method is suggested as a standard future element of mass spectrometers to aid online structural characterization of unknowns and to study conformational changes of proteins with hydrogen/deuterium exchange.

  8. Human Umbilical Cord Blood Cell Transplantation in Neuroregenerative Strategies

    Science.gov (United States)

    Galieva, Luisa R.; Mukhamedshina, Yana O.; Arkhipova, Svetlana S.; Rizvanov, Albert A.

    2017-01-01

    At present there is no effective treatment of pathologies associated with the death of neurons and glial cells which take place as a result of physical trauma or ischemic lesions of the nervous system. Thus, researchers have high hopes for a treatment based on the use of stem cells (SC), which are potentially able to replace dead cells and synthesize neurotrophic factors and other molecules that stimulate neuroregeneration. We are often faced with ethical issues when selecting a source of SC. In addition to precluding these, human umbilical cord blood (hUCB) presents a number of advantages when compared with other sources of SC. In this review, we consider the key characteristics of hUCB, the results of various studies focused on the treatment of neurodegenerative diseases (Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis), ischemic (stroke) and traumatic injuries of the nervous system and the molecular mechanisms of hUCB-derived mononuclear and stem cells. PMID:28951720

  9. Frequency of sister chromatid exchanges in lymphocyte cultures of human peripheral blood after the combined effect of γ-radiation and caffeine

    International Nuclear Information System (INIS)

    Nugis, V.Yu.; Pyatkin, E.K.

    1986-01-01

    Keeping of human peripheral blood lymphocytes, irradiated in vitro with 60 Co-γ-quanta at a dose of 3 Gy at G 0 phase, with caffeine of 16 and 160 μg/ml during cultivation with PHA had no appreciable influence on the fraquency of sister chromatid exchanges. A minor increase in the number of sister chromatid exchanges was only noted when nonirradiated and irradiated lymphocytes were cultured with 160 μg/ml caffeine

  10. An ultrafiltration technique for labeling red blood cells with Tc-99m

    International Nuclear Information System (INIS)

    Hendershott, L.R.; Gatson, R.C.; Ordway, F.S.; Ahmad, M.; Saint Louis Univ., MO; Saint Louis Univ., MO

    1979-01-01

    This method automates the preparation of autologous Tc-99m labeled red blood cells utilizing the Amicon on-line column eluate concentrator to separate the plasma from the red blood cells. The red blood cells were pre-tinned with stannous diphosphonate and continuously recirculated over a 0.6 μ filter until all of the plasma was removed and the red blood cells remained suspended in a solution of 0.9% sodium chloride. Once the plasma has been removed the red blood cells are incubated with Tc-99m pertechnetate. The above Tc-99m red blood cells were compared to Tc-99m red blood cells produced in a similar manner except that centrifugation was used to separate the red blood cells from the plasma. Both preparations had a tagging efficiency of 98% or greater and rat distribution studies demonstrate that both preparations are equally stable as an in vivo intravascular agent. (orig.) [de

  11. Emergency transfusion of patients with unknown blood type with blood group O Rhesus D positive red blood cell concentrates: a prospective, single-centre, observational study.

    Science.gov (United States)

    Selleng, Kathleen; Jenichen, Gregor; Denker, Kathrin; Selleng, Sixten; Müllejans, Bernd; Greinacher, Andreas

    2017-05-01

    Emergency patients with unknown blood type usually receive O Rhesus D negative (RhD-) red blood cell concentrates until their blood group is determined to prevent RhD+ related adverse transfusion reactions. As 85% of individuals are RhD+, this consumption of O RhD- red blood cell concentrates contributes to shortages of O RhD- red blood cell concentrates, sometimes forcing transfusion of known RhD- patients with RhD+ red blood cell concentrates. Here we report the outcome of this transfusion policy transfusing all emergency patients with unknown blood type with O RhD+ red blood cell concentrates. In this prospective single-centre observational study done between Jan 1, 2001, and Dec 31, 2015, we assessed all consecutive RhD- patients at the University Medicine Greifswald who received RhD+ red blood cell concentrates (emergency patients with unknown blood type; and RhD- patients receiving RhD+ red blood cell concentrates during RhD- red blood cell concentrate shortages). No patients were excluded. The primary endpoint was anti-D allo-immunisation at 2 months follow-up or later. Patients were followed up and tested for immunisation against red blood cell antigens using the direct antiglobulin test and an antibody screen every 3-5 days for 4 weeks or until death, or hospital discharge. Surviving patients were screened for development of anti-D antibodies for up to 12 months (at the predefined timepoints 2, 3, 6, and 12 months) after RhD+ red blood cell transfusion. 437 emergency patients, of whom 85 (20%) were RhD-, received 2836 RhD+ red blood cell concentrates. The overall risk of inducing anti-D antibodies (in all 437 recipients) was 17 (4%, 95% CI 2·44-6·14) of 437 (assuming all patients lost to follow-up developed anti-D allo-immunisation). During this period, 110 known RhD- patients received RhD+ red blood cell concentrates during RhD- red blood cell concentrate shortages. Of these, 29 (26%; 95% CI 19·0-35·3) developed anti-D allo-immunisation (assuming all

  12. Preliminary study on mononuclear cells insulin receptor in porcine blood

    International Nuclear Information System (INIS)

    Dalimunthe, D.; Hara, Hitoshi; Hayashi, Hirofumi; Mito, Kazuyo; Kawate, Ryoso

    1980-01-01

    Insulin receptor of porcine mononuclear cells was investigated. After passaging over a Boyum method gradient, mononuclear cells from freshly collected heparinized blood were isolated and 1 x 10 7 /ml mononuclear cells were incubated for 24 hrs at 4 0 C in Tris-salt buffer pH 8.0 with 125 I-insulin (2.2 ng/ml) and a range of native insulin concentration from 0 to 1 x 10 3 ng/ml. γ-globulin-polyethylene glycol was used to separate the unbound 125 I-insulin from the incubation mixture. After centrifugation the supernatant was discarded, the radioactivity of the cell pellets were counted in a gammacounter and the percentage of 125 I-insulin bound could be determined. The result demonstrated that circulating porcine mononuclear cells prepared from Ficoll-Conray gradient readily bound with 125 I-insulin. The binding of 125 I-insulin to porcine mononuclear cells was rapid and reversible process, and could be inhibited by physiological amount of native insulin. 125 I-insulin binding to porcine mononuclear cells was a linear function of cell concentration and a saturable ability of native insulin to displace the binding of 125 I-insulin. (author)

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

    International Nuclear Information System (INIS)

    Parker, J.C.

    1984-01-01

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

  14. Transplantation? Peripheral Stem Cell/Bone Marrow/Cord Blood

    Directory of Open Access Journals (Sweden)

    Itır Sirinoglu Demiriz

    2012-01-01

    Full Text Available The introduction of peripheral stem cell (PSC and cord blood (CB as an alternative to bone marrow (BM recently has caused important changes on hematopoietic stem cell transplantation (HSCT practice. According to the CIBMTR data, there has been a significant decrease in the use of bone marrow and increase in the use of PSC and CB as the stem cell source for HSCT performed during 1997–2006 period for patients under the age of 20. On the other hand, the stem cell source in 70% of the HSCT procedures performed for patients over the age of 20 was PSC and the second most preferred stem cell source was bone marrow. CB usage is very limited for the adult population. Primary disease, stage, age, time and urgency of transplantation, HLA match between the patient and the donor, stem cell quantity, and the experience of the transplantation center are some of the associated factors for the selection of the appropriate stem cell source. Unfortunately, there is no prospective randomized study aimed to facilitate the selection of the correct source between CB, PSC, and BM. In this paper, we would like to emphasize the data on stem cell selection in light of the current knowledge for patient populations according to their age and primary disease.

  15. Proton exchange fuel cell : the design, construction and evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Heinzen, M.R.; Simoes, G.C.; Da Silva, L. [Univ. do Vale do Itajai, Sao Jose, SC (Brazil). Lab. de Pesquisa em Energia; Fiori, M.A.; Paula, M.M.S. [Univ. do Extremo Sul Catarinense, Santa Catarina (Brazil). Lab. de Sintese de Complexos Multifuncionais; Benavides, R. [Centro de Investigacion en Quimica Aplicada, Coahuila (Mexico)

    2010-07-15

    Polymer electrolyte membrane fuel cells (PEMFC) convert the chemical energy stored in the fuel directly into electrical energy without intermediate steps. The PEMFC operates at a relatively low operating temperature making it a good choice for mobile applications, but a high power density is needed in order to decrease the total weight of the vehicles. This paper presented a simple methodology to construct a PEMFC-type fuel cell, with particular reference to the gaseous diffuser, cell structure, the fixing plate, mounting bracket, gas distribution plates, and the membrane electrode assembly (MEA). The geometric design and meshing of the PEMFC were also described. The electrode was made using graphite with flow-field geometry. The PEMFC was tested for 100 hour of continuous work, during which time the current and voltage produced were monitored in order to evaluate the performance of the PEMFC. The materials used in the preparation of the fuel cell proved to be suitable. There was no loss of efficiency during the tests. The most relevant aspects affecting the PEMFC design were examined in an effort to optimize the performance of the cell. 13 refs., 6 figs.

  16. Blood Cell Mitochondrial DNA Content and Premature Ovarian Aging

    Science.gov (United States)

    Cacciatore, Chiara; Busnelli, Marta; Rossetti, Raffaella; Bonetti, Silvia; Paffoni, Alessio; Mari, Daniela; Ragni, Guido; Persani, Luca; Arosio, M.; Beck-Peccoz, P.; Biondi, M.; Bione, S.; Bruni, V.; Brigante, C.; Cannavo`, S.; Cavallo, L.; Cisternino, M.; Colombo, I.; Corbetta, S.; Crosignani, P.G.; D'Avanzo, M.G.; Dalpra, L.; Danesino, C.; Di Battista, E.; Di Prospero, F.; Donti, E.; Einaudi, S.; Falorni, A.; Foresta, C.; Fusi, F.; Garofalo, N.; Giotti, I.; Lanzi, R.; Larizza, D.; Locatelli, N.; Loli, P.; Madaschi, S.; Maghnie, M.; Maiore, S.; Mantero, F.; Marozzi, A.; Marzotti, S.; Migone, N.; Nappi, R.; Palli, D.; Patricelli, M.G.; Pisani, C.; Prontera, P.; Petraglia, F.; Radetti, G.; Renieri, A.; Ricca, I.; Ripamonti, A.; Rossetti, R.; Russo, G.; Russo, S.; Tonacchera, M.; Toniolo, D.; Torricelli, F.; Vegetti, W.; Villa, N.; Vineis, P.; Wasniewsk, M.; Zuffardi, O.

    2012-01-01

    Primary ovarian insufficiency (POI) is a critical fertility defect characterized by an anticipated and silent impairment of the follicular reserve, but its pathogenesis is largely unexplained. The frequent maternal inheritance of POI together with a remarkable dependence of ovarian folliculogenesis upon mitochondrial biogenesis and bioenergetics suggested the possible involvement of a generalized mitochondrial defect. Here, we verified the existence of a significant correlation between blood and ovarian mitochondrial DNA (mtDNA) content in a group of women undergoing ovarian hyperstimulation (OH), and then aimed to verify whether mtDNA content was significantly altered in the blood cells of POI women. We recruited 101 women with an impaired ovarian reserve: 59 women with premature ovarian failure (POF) and 42 poor responders (PR) to OH. A Taqman copy number assay revealed a significant mtDNA depletion (P<0.001) in both POF and PR women in comparison with 43 women of similar age and intact ovarian reserve, or 53 very old women with a previous physiological menopause. No pathogenic variations in the mitochondrial DNA polymerase γ (POLG) gene were detected in 57 POF or PR women with low blood mtDNA content. In conclusion, blood cell mtDNA depletion is a frequent finding among women with premature ovarian aging, suggesting that a still undetermined but generalized mitochondrial defect may frequently predispose to POI which could then be considered a form of anticipated aging in which the ovarian defect may represent the first manifestation. The determination of mtDNA content in blood may become an useful tool for the POI risk prediction. PMID:22879975

  17. Resting blood lactate in individuals with sickle cell disease

    Science.gov (United States)

    Petto, Jefferson; de Jesus, Jaqueline Brito; Vasques, Leila Monique Reis; Pinheiro, Renata Leão Silva; Oliveira, Aila Mascarenhas; Spinola, Kelly Aparecida Borges; Silva, Wellington dos Santos

    2011-01-01

    Background The most common hereditary hemoglobin disorder, affecting 20 million individuals worldwide, is sickle cell disease. The vascular obstruction resulting from the sickling of cells in this disease can produce local hypoxemia, pain crises and infarction in several tissues, including the bones, spleen, kidneys and lungs. Objective To determine red blood group genes in a Brazilian populations. Methods The present study is characterized as a case control study, with the aim of identifying the baseline blood lactate concentration in individuals with hemoglobin SS and SC diseases. One-way ANOVA with the Tukey post-test was used to analyze the results and a p-value < 0.05 was considered significant. Calculations were made using the INSTAT statistical program. The graphs were generated using the ORING program. The study sample was composed of 31 men and women residing in the city of Santo Antônio de Jesus, Bahia, Brazil. The individuals were divided into two groups: Group GC of 16 subjects who did not present with any type of structural hemoglobinopathy; and Group GE composed of 15 individuals with ages between 2 and 35 years old, who had the SS and SC genotypes. Sample analyses were performed with 3 mL of blood during fasting. Results The baseline blood lactate concentration of the SS and SC individuals was higher than that of the control group (p<0.001) with means of 4.86 ± 0.95; 3.30 ± 0.33; 1.31 ± 0.08 IU/L for SS, SC and controls, respectively. This corroborates the initial research hypothesis. Conclusion The baseline blood lactate of SS and SC individuals is 3 to 4 times higher than that of healthy subjects, probably due to the fact that these patients have a metabolic deviation to the anaerobic pathway. PMID:23284239

  18. The Effect of Perinatal Hypoxia on Red Blood Cell Morphology in Newborns

    Directory of Open Access Journals (Sweden)

    S. A. Perepelitsa

    2017-01-01

    . Conclusion. Perinatal hypoxia alters RBC morphology and impairs the nanostructure of membranes. These changes confirmed the effect of the hypoxia degree on all nanostructures of RBC membranes: phospholipid bilayer, protein elements of the membrane, spectrin matrix. Changes in heights and spatial periods of the red blood cell membrane surfaces h1 and h3 associated with hypoxia apparently are aimed at a compensatory increase in the red blood cell membrane surface contributing to the increase of the gas exchange area. These changes may represent adaptive responses to hypoxia aimed to preserve the functional capabilities of red blood cells. The course of an early adaptation period (post-hypoxic period is characterized by the instability of all nanostructures of red blood cell membranes and a greater variability of morphological forms. Effects of perinatal hypoxia on the red blood cell membrane persist for some time and go beyond the early neonatal period.

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

    DEFF Research Database (Denmark)

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

    2017-01-01

    received transfusions from 2003 to 2012. Measurements: Patients were followed from first blood transfusion. Relative and absolute risks for death in 30 days or 1 year in relation to length of RBC storage were assessed by using 3 independent analytic approaches. All analyses were conducted by using Cox......Background: Possible negative effects, including increased mortality, among persons who receive stored red blood cells (RBCs) have recently garnered considerable attention. Despite many studies, including 4 randomized trials, no consensus exists. Objective: To study the association between...... the length of RBC storage and mortality in a large population-based cohort of patients who received transfusions, allowing detection of small yet clinically significant effects. Design: Binational cohort study. Setting: All transfusion recipients in Sweden and Denmark. Patients: 854 862 adult patients who...

  20. Stem Cell Heterogeneity of Mononucleated Cells from Murine Peripheral Blood: Molecular Analysis

    Directory of Open Access Journals (Sweden)

    Muhammad Dain Yazid

    2011-01-01

    Full Text Available The main purpose of this paper was to determine the heterogeneity of primary isolated mononucleated cells that originated from the peripheral blood system by observing molecular markers. The isolated cells were cultured in complete medium for 4 to 7 days prior to the separation of different cell types, that is, adherent and suspension. Following a total culture time of 14 days, adherent cells activated the Cd105 gene while suspension cells activated the Sca-1 gene. Both progenitor markers, Cbfa-1 and Ostf-1, were inactivated in both suspension and adherent cells after 14-day culture compared to cells cultured 3 days in designated differentiation medium. In conclusion, molecular analyses showed that primary mononucleated cells are heterogeneous, consisting of hematopoietic stem cells (suspension and mesenchymal stem cells (adherent while both cells contained no progenitor cells.

  1. Smooth muscle progenitor cells from peripheral blood promote the neovascularization of endothelial colony-forming cells

    Energy Technology Data Exchange (ETDEWEB)

    Joo, Hyung Joon; Seo, Ha-Rim [Department of Cardiology, Cardiovascular Center, College of Medicine, Korea University, Seoul (Korea, Republic of); Jeong, Hyo Eun [Department of Mechanical Engineering, Korea University, Seoul (Korea, Republic of); Choi, Seung-Cheol; Park, Jae Hyung; Yu, Cheol Woong; Hong, Soon Jun [Department of Cardiology, Cardiovascular Center, College of Medicine, Korea University, Seoul (Korea, Republic of); Chung, Seok [Department of Mechanical Engineering, Korea University, Seoul (Korea, Republic of); Lim, Do-Sun, E-mail: dslmd@kumc.or.kr [Department of Cardiology, Cardiovascular Center, College of Medicine, Korea University, Seoul (Korea, Republic of)

    2014-07-11

    Highlights: • Two distinct vascular progenitor cells are induced from adult peripheral blood. • ECFCs induce vascular structures in vitro and in vivo. • SMPCs augment the in vitro and in vivo angiogenic potential of ECFCs. • Both cell types have synergistic therapeutic potential in ischemic hindlimb model. - Abstract: Proangiogenic cell therapy using autologous progenitors is a promising strategy for treating ischemic disease. Considering that neovascularization is a harmonized cellular process that involves both endothelial cells and vascular smooth muscle cells, peripheral blood-originating endothelial colony-forming cells (ECFCs) and smooth muscle progenitor cells (SMPCs), which are similar to mature endothelial cells and vascular smooth muscle cells, could be attractive cellular candidates to achieve therapeutic neovascularization. We successfully induced populations of two different vascular progenitor cells (ECFCs and SMPCs) from adult peripheral blood. Both progenitor cell types expressed endothelial-specific or smooth muscle-specific genes and markers, respectively. In a protein array focused on angiogenic cytokines, SMPCs demonstrated significantly higher expression of bFGF, EGF, TIMP2, ENA78, and TIMP1 compared to ECFCs. Conditioned medium from SMPCs and co-culture with SMPCs revealed that SMPCs promoted cell proliferation, migration, and the in vitro angiogenesis of ECFCs. Finally, co-transplantation of ECFCs and SMPCs induced robust in vivo neovascularization, as well as improved blood perfusion and tissue repair, in a mouse ischemic hindlimb model. Taken together, we have provided the first evidence of a cell therapy strategy for therapeutic neovascularization using two different types of autologous progenitors (ECFCs and SMPCs) derived from adult peripheral blood.

  2. Volume-dependent K+ transport in rabbit red blood cells comparison with oxygenated human SS cells

    Energy Technology Data Exchange (ETDEWEB)

    Al-Rohil, N.; Jennings, M.L.

    1989-07-01

    In this study the volume-dependent or N-ethylmaleimide (NEM)-stimulated, ouabain-insensitive K+ influx and efflux were measured with the tracer 86Rb+ in rabbit red blood cells. The purpose of the work was to examine the rabbit as a potential model for cell volume regulation in human SS red blood cells and also to investigate the relationship between the NEM-reactive sulfhydryl group(s) and the signal by which cell swelling activates the transport. Ouabain-resistant K+ efflux and influx increase nearly threefold in cells swollen hypotonically by 15%. Pretreatment with 2 mM NEM stimulates efflux 5-fold and influx 10-fold (each measured in an isotonic medium). The ouabain-resistant K+ efflux was dependent on the major anion in the medium. The anion dependence of K+ efflux in swollen or NEM-stimulated cells was as follows: Br- greater than Cl- much greater than NO3- = acetate. The magnitudes of both the swelling- and the NEM-stimulated fluxes are much higher in young cells (density separated but excluding reticulocytes) than in older cells. Swelling- or NEM-stimulated K+ efflux in rabbit red blood cells was inhibited 50% by 1 mM furosemide, and the inhibitory potency of furosemide was enhanced by extracellular K+, as is known to be true for human AA and low-K+ sheep red blood cells. The swelling-stimulated flux in both rabbit and human SS cells has a pH optimum at approximately 7.4. We conclude that rabbit red blood cells are a good model for swelling-stimulated K+ transport in human SS cells.

  3. Commercialization of proton exchange membrane fuel cells for transportation applications

    Energy Technology Data Exchange (ETDEWEB)

    Wismer, L.

    1996-04-01

    Environmental concerns with air quality and global warming have triggered strict federal ambient ozone air quality standards. Areas on non-attainment of these standards exist across the United States. Because it contains several of the most difficult attainment areas, the State of California has adopted low emission standards including a zero emission vehicle mandate that has given rise to development of hybrid electric vehicles, both battery-powered and fuel-cell powered. Fuel cell powered vehicles, using on-board hydrogen as a fuel, share the non-polluting advantage of the battery electric vehicle while offering at least three times the range today`s battery technology.

  4. MORPHOMETRIC CHARACTERISTICS OF RED BLOOD CELLS OF Telestes metohiensis (Steindachner, 1901)

    OpenAIRE

    Radoslav Dekić; Aleksander Ivanc; Milica Lukač; Josip Krnić

    2013-01-01

    The paper presents the morphometric characteristics of red blood cells of endemic fish species of Bosnia and Herzegovina, Telestes metohiensis (Steindachner, 1901) inhabiting the Vrijeka river in the Dabar field. A total of 30 fish were sampled during August, 2010. Morphological measurements included the following parameters: axes of the red blood cells and nuclei, the surface of the red blood cells and nuclei and the thickness of the red blood cells. Morphometric characteristics of the eryth...

  5. Bioactive compounds from crocodile (Crocodylus siamensis) white blood cells induced apoptotic cell death in hela cells.

    Science.gov (United States)

    Patathananone, Supawadee; Thammasirirak, Sompong; Daduang, Jureerut; Chung, Jing Gung; Temsiripong, Yosapong; Daduang, Sakda

    2016-08-01

    Crocodile (Crocodylus siamensis) white blood cell extracts (WBCex) were examined for anticancer activity in HeLa cell lines using the MTT assay. The percentage viability of HeLa cells significantly deceased after treatment with WBCex in a dose- and time-dependent manner. The IC50 dose was suggested to be approximately 225 μg/mL protein. Apoptotic cell death occurred in a time-dependent manner based on investigation by flow cytometry using annexin V-FITC and PI staining. DAPI nucleic acid staining indicated increased chromatin condensation. Caspase-3, -8 and -9 activities also increased, suggesting the induction of the caspase-dependent apoptotic pathway. Furthermore, the mitochondrial membrane potential (ΔΨm ) of HeLa cells was lost as a result of increasing levels of Bax and reduced levels of Bcl-2, Bcl-XL, Bcl-Xs, and XIAP. The decreased ΔΨm led to the release of cytochrome c and the activation of caspase-9 and -3. Apoptosis-inducing factor translocated into the nuclei, and endonuclease G (Endo G) was released from the mitochondria. These results suggest that anticancer agents in WBCex can induce apoptosis in HeLa cells via both caspase-dependent and -independent pathways. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 986-997, 2016. © 2015 Wiley Periodicals, Inc.

  6. Intraoperative blood salvage may shorten the lifespan of red blood cells within 3 days postoperatively

    Science.gov (United States)

    Liao, Xin-Yi; Zuo, Shan-Shan; Meng, Wen-Tong; Zhang, Jie; Huang, Qin; Gou, Da-Ming

    2017-01-01

    Abstract Background: Intraoperative blood salvage (IBS) recovers most lost blood, and is widely used in the clinic. It is unclear why IBS does not reduce long-term postoperative requirements for red blood cells (RBCs), and 1 possibility is that IBS affects RBC lifespan. Methods: Prospectively enrolled patients who underwent spine, pelvic, or femur surgery not involving allogeneic RBC transfusion were grouped based on whether they received IBS or not. Volumes of blood lost and of RBCs salvaged during surgery were recorded. Total blood cell counts, levels of plasma-free hemoglobin, and CD235a-positive granulocytes were determined perioperatively. Results: Although intraoperative blood loss was higher in the IBS group (n = 45) than in the non-IBS group (n = 52) (P < .001), hemoglobin levels were similar between groups (P = .125) at the end of surgery. Hemoglobin levels increased in non-IBS patients (4 ± 11 g/L), but decreased in IBS patients (−7 ± 12 g/L) over the first 3 postoperative days. Nadir hemoglobin levels after surgery were higher in the non-IBS group (107 ± 12 g/L) than in the IBS group (91 ± 12 g/L). Salvaged RBC volume correlated with hemoglobin decrease (r = 0.422, P = .004). In multivariate analysis, salvaged RBC volume was an independent risk factor for hemoglobin decrease (adjusted odds ratio 1.002, 95% confidence interval 1.001–1.004, P = .008). Flow cytometry showed the numbers of CD235a-positive granulocytes after surgery to be higher in the IBS group than in the non-IBS group (P < .05). Conclusion: IBS may shorten the lifespan of RBCs by triggering their engulfment upon re-infusion (China Clinical Trial Registry ChiCTR-OCH-14005140). PMID:28953650

  7. Polymers application in proton exchange membranes for fuel cells (PEMFCs)

    Science.gov (United States)

    Walkowiak-Kulikowska, Justyna; Wolska, Joanna; Koroniak, Henryk

    2017-07-01

    This review presents the most important research on alternative polymer membranes with ionic groups attached, provides examples of materials with a well-defined chemical structure that are described in the literature. Furthermore, it elaborates on the synthetic methods used for preparing PEMs, the current status of fuel cell technology and its application. It also briefly discusses the development of the PEMFC market.

  8. Application of Proton Exchange Membrane Fuel Cell for Lift Trucks

    DEFF Research Database (Denmark)

    Hosseinzadeh, Elham; Rokni, Masoud

    2011-01-01

    in order to account for water back diffusion. Further Membrane water content is assumed to be a linear function of thickness. PEM fuel cell is working at rather low operating conditions which makes it suitable for the automotive systems. In this paper motive power part of a lift truck has been investigated...

  9. Blood transfusion in children with sickle cell disease undergoing tonsillectomy.

    Science.gov (United States)

    Atwood, Carlyn M; Gnagi, Sharon H; Teufel, Ronald J; Nguyen, Shaun A; White, David R

    2017-12-01

    Tonsillectomy is the second most common surgery in children with sickle cell disease. These children are at an increased risk of perioperative complications due to vaso-occlusive events. Although controversial, preoperative blood transfusions are sometimes given in an effort to prevent such complications. The purpose of this study is to analyze trends in the use of blood transfusion for management of children with sickle cell disease (SCD) undergoing tonsillectomy in a national database. Patients in the 1997-2012 KID with a primary procedure matching the ICD-9 procedure code for tonsillectomy (28.2-28.3) and diagnosis code for SCD (282.60-282.69) were examined. Patients were split into groups by blood transfusion status and compared across variables including complication rate, length of stay (LOS), and hospital charges. Statistical analysis included chi-square test for trend, Mann-Whitney U test, and independent t-test. 1133 patients with SCD underwent tonsillectomy. There was a strong positive correlation between increasing chronologic year and the proportion of patients receiving blood transfusions, 47 (30.1%) in 1997 to 78 (42.5%) in 2012 (r = 0.94, p = 0.005). During this period, there was no significant change in the rate of complications (r = -0.1, p = 0.87). Overall, patients receiving blood transfusion had a longer mean LOS (3.1 ± 2.4 days vs. 2.5 ± 2.2 days, p blood transfusion. The rate of complications in the transfusion group, 18 of 352(5.1%), was not significantly different (p = 0.48) from the group without transfusion, 40 of 626 (6.4%). From 1997 to 2012, there was a significant increase in the proportion of patients with SCD receiving perioperative blood transfusions for tonsillectomy. While the frequency of transfusion rose, those who received a transfusion had similar complication rates with increased charges and length of hospital stays compared to those who did not receive a transfusion. Copyright © 2017 Elsevier B.V. All

  10. Cell Phone Information Seeking Explains Blood Pressure in African American Women.

    Science.gov (United States)

    Jones, Lenette M; Veinot, Tiffany C; Pressler, Susan J

    2018-05-01

    Although cell phone use and Internet access via cell phone is not marked by racial disparities, little is known about how cell phone use relates to blood pressure and health information seeking behaviors. The purposes of this study were to (a) describe Internet activities, cell phone use, and information seeking; (b) determine differences in blood pressure and information seeking between cell phone information seekers and nonseekers; and (c) examine cell phone information seeking as a predictor of blood pressure in African American women. Participants ( N = 147) completed a survey and had their blood pressure measured. Independent-sample t tests showed a significant difference in systolic blood pressure in cell phone information seekers and nonseekers. Linear regression revealed cell phone information seeking as an independent predictor of systolic blood pressure, despite confounders. It is possible that cell phone information seekers were using health information to make decisions about self-management of blood pressure.

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

    Directory of Open Access Journals (Sweden)

    Djuna Zoe de Back

    2014-01-01

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

  12. Comparative study of red blood cell method in rat and calves blood as alternatives of Draize eye irritation test.

    Science.gov (United States)

    Lagarto, A; Vega, R; Vega, Y; Guerra, I; González, R

    2006-06-01

    Red blood cell assay (RBC) is used to estimate potential irritation of tensioactive agents and detergents. Cell membrane lysis and cell protein denaturation are measured photometrically. This study was aimed to determine if rat blood cells can be used to predict eye potential irritation in the same way of calves blood cells in RBC assay. We evaluated 20 cosmetic formulations using rat and calves blood according to INVITOX protocol No 37. Data of media hemolysis concentration, denaturation index and the ratio of both parameters were compared with in vivo data of eye irritancy. There was a significant difference (ptest. The RBC assay using calves blood showed better results. Several test substances were false negatives with rat blood. This high false negative rate would be correctly identified by the animal test but it may also lead to increased animal consumption. For that RBC assay with calf blood cells is preferable to the employment of rat blood as screening method with a reduction and refinement strategy.

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

    NARCIS (Netherlands)

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

    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

  14. Blood cell-derived tissue factor influences host response during murine endotoxemia

    NARCIS (Netherlands)

    Schoenmakers, Saskia H. H. F.; Groot, Angelique P.; Florquin, Sandrine; Reitsma, Pieter H.; Spek, C. Arnold

    2004-01-01

    During endotoxemia, blood coagulation becomes activated due to tissue factor (TF) expression on leukocytes and/or endothelial cells. We investigated the influence of blood cell-derived tissue factor on murine endotoxemia. Therefore, we generated mice that lack tissue factor on their blood cells by

  15. The impact of storage on red cell function in blood transfusion

    NARCIS (Netherlands)

    Almac, Emre; Ince, Can

    2007-01-01

    Despite the common use of red-blood-cell transfusions in clinical practice, actual beneficial effects of red blood cells have never been demonstrated. On the contrary, several studies suggest that red-blood-cell transfusions are associated with higher risks of morbidity and mortality. The effects of

  16. Fetal red blood cell parameters in thalassemia and hemoglobinopathies.

    Science.gov (United States)

    Karnpean, Rossarin; Fucharoen, Goonnapa; Fucharoen, Supan; Ratanasiri, Thawalwong

    2013-01-01

    With the lack of fetal blood specimens in routine practice, little is known about red blood cell (RBC) parameters of fetuses with various thalassemia syndromes. This study aimed to describe these in various forms of thalassemia. The study was performed on 93 fetal blood specimens obtained from pregnant women by cordocentesis during 18-24 weeks of gestation. RBC parameters were recorded on automated analyzer. Hemoglobin (Hb) and DNA analyses were performed for definite genotyping. No significant difference in RBC parameters was observed between non-thalassemic fetuses and those with β-thalassemia trait, Hb E trait, homozygous Hb E and β-thalassemia/Hb E disease. However, in those with α(0)-thalassemia trait and double heterozygous α(0)-thalassemia/Hb E, slight reduction in mean corpuscular volume (MCV) was noted. Fetuses with the Hb H disease showed significant reductions in Hb, MCV and mean corpuscular Hb (MCH). Marked reductions in Hb, hematocrit, MCH and mean cell Hb concentration and increased RBC distribution width with numerous nucleated RBC were clearly observed in Hb Bart's hydrops fetalis. Simple analysis of fetal RBC parameters is useful for making presumptive prenatal diagnosis of α-thalassemia syndromes including Hb H disease and Hb Bart's hydrops fetalis which can then be confirmed by Hb and DNA analyses. Copyright © 2013 S. Karger AG, Basel.

  17. Nucleated red blood cells in infants of smoking mothers.

    Science.gov (United States)

    Yeruchimovich, M; Dollberg, S; Green, D W; Mimouni, F B

    1999-03-01

    To evaluate whether the absolute nucleated red blood cell (RBC) count is elevated in term, appropriate for gestational age (AGA) infants born to smoking women. We compared absolute nucleated RBC counts taken during the first 12 hours of life in two groups of term, vaginally delivered, AGA infants, one group born to mothers who smoked during pregnancy (n = 30) and the other born to mothers who did not smoke (n = 30). We excluded infants of women with diabetes, hypertension, or alcohol or drug abuse, and infants with heart rate abnormalities, hemolysis, blood loss, or chromosomal anomalies. There were no differences between the groups in birth weight, gestational age, maternal age, gravidity, parity, maternal analgesia during labor, 1- and 5-minute Apgar scores, corrected white blood cell counts, lymphocyte counts, or hematocrits. The median absolute nucleated RBC count in infants of smoking mothers was 0.5 x 10(9)/L (range 0 to 5.0) versus 0.0005 x 10(9)/L (range 0 to 0.6) in nonsmoking controls (P mothers have increased circulating absolute nucleated RBC counts compared with controls. The absolute nucleated RBC count in newborns correlates with the number of cigarettes smoked during pregnancy.

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

    Science.gov (United States)

    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.

  19. Generation of erythroid cells from polyploid giant cancer cells: re-thinking about tumor blood supply.

    Science.gov (United States)

    Yang, Zhigang; Yao, Hong; Fei, Fei; Li, Yuwei; Qu, Jie; Li, Chunyuan; Zhang, Shiwu

    2018-04-01

    During development and tumor progression, cells need a sufficient blood supply to maintain development and rapid growth. It is reported that there are three patterns of blood supply for tumor growth: endothelium-dependent vessels, mosaic vessels, and vasculogenic mimicry (VM). VM was first reported in highly aggressive uveal melanomas, with tumor cells mimicking the presence and function of endothelial cells forming the walls of VM vessels. The walls of mosaic vessels are randomly lined with both endothelial cells and tumor cells. We previously proposed a three-stage process, beginning with VM, progressing to mosaic vessels, and eventually leading to endothelium-dependent vessels. However, many phenomena unique to VM channel formation remain to be elucidated, such as the origin of erythrocytes before VM vessels connect with endothelium-dependent vessels. In adults, erythroid cells are generally believed to be generated from hematopoietic stem cells in the bone marrow. In contrast, embryonic tissue obtains oxygen through formation of blood islands, which are largely composed of embryonic hemoglobin with a higher affinity with oxygen, in the absence of mature erythrocytes. Recent data from our laboratory suggest that embryonic blood-forming mechanisms also exist in cancer tissue, particularly when these tissues are under environmental stress such as hypoxia. We review the evidence from induced pluripotent stem cells in vitro and in vivo to support this previously underappreciated cell functionality in normal and cancer cells, including the ability to generate erythroid cells. We will also summarize the current understanding of tumor angiogenesis, VM, and our recent work on polyploid giant cancer cells, with emphasis on their ability to generate erythroid cells and their association with tumor growth under hypoxia. An alternative embryonic pathway to obtain oxygen in cancer cells exists, particularly when they are under hypoxic conditions.

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

    NARCIS (Netherlands)

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

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

  1. Early occurrence of red blood cell alloimmunization in patients with sickle cell disease

    NARCIS (Netherlands)

    Sins, Joep W. R.; Biemond, Bart J.; van den Bersselaar, Sil M.; Heijboer, H.; Rijneveld, Anita W.; Cnossen, Marjon H.; Kerkhoffs, Jean-Louis H.; van Meurs, Alfred H.; von Ronnen, F. B.; Zalpuri, Saurabh; de Rijke, Yolanda B.; Ellen van der Schoot, C.; de Haas, Masja; van der Bom, Johanna G.; Fijnvandraat, Karin

    2016-01-01

    Red blood cell (RBC) alloimmunization is a major complication of transfusion therapy in sickle cell disease (SCD). Identification of high-risk patients is hampered by lack of studies that take the cumulative transfusion exposure into account. In this retrospective cohort study among previously

  2. Cerebral blood flow mapping in children with sickle cell disease

    International Nuclear Information System (INIS)

    Numaguchi, Y.; Humbert, J.R.; Robinson, A.E.; Lindstrom, W.W.; Gruenauer, L.M.

    1988-01-01

    A cerebral blood flow mapping system was applied to the evaluation of cerebral blood flow (CBF) in 21 patients with sickle cell cerebrovascular disease, by means of a Picker xenon computed tomographic (CT) scanner. Results indicate that (1) xenon CT is a safe and reliable procedure in children with cerebrovascular diseases; (2) CBF in the gray matter of children seems to be higher than in previously reported data obtained with use of isotopes; and (3) regional CBF can be altered significantly by changing the size of the region of interest (ROI). The term regional CBF probably has to be carefully defined in xenon CT flow mapping. Correlation with anatomy by means of CT or magnetic resonance imaging and comparison with the ROI of the contralateral side and/or adjacent sections is important

  3. Characterization of proton exchange membrane fuel cell anode catalysts prepared by colloid method

    Energy Technology Data Exchange (ETDEWEB)

    Franco, E.G.; Dantas-Filho, P.L.; Burani, G.F. [Universidade de Sao Paulo (IEE/USP), Sao Paulo, SP (Brazil). Instituto de Eletrotecnica e Energia

    2009-07-01

    Full text: Anode catalysts for Proton Exchange Membrane Fuel Cell (PEMFC) were synthesized by the colloid method and their structure was investigated by transmission electron microscopy (TEM), energy dispersive analyses (EDS), X-ray Diffraction (XRD). The electrochemical behavior of the anode catalyst was analyzed by cyclic voltammetry (CV) and polarization curves (UxI). (author)

  4. Phosphoric acid doped imidazolium polysulfone membranes for high temperature proton exchange membrane fuel cells

    DEFF Research Database (Denmark)

    Yang, Jingshuai; Li, Qingfeng; Jensen, Jens Oluf

    2012-01-01

    A novel acid–base polymer membrane is prepared by doping of imidazolium polysulfone with phosphoric acid for high temperature proton exchange membrane fuel cells. Polysulfone is first chloromethylated, followed by functionalization of the chloromethylated polysulfone with alkyl imidazoles i.e. me...

  5. Importance of balancing membrane and electrode water in anion exchange membrane fuel cells

    Science.gov (United States)

    Omasta, T. J.; Wang, L.; Peng, X.; Lewis, C. A.; Varcoe, J. R.; Mustain, W. E.

    2018-01-01

    Anion exchange membrane fuel cells (AEMFCs) offer several potential advantages over proton exchange membrane fuel cells (PEMFCs), most notably to overcome the cost barrier that has slowed the growth and large scale implementation of fuel cells for transportation. However, limitations in performance have held back AEMFCs, specifically in the areas of stability, carbonation, and maximum achievable current and power densities. In order for AEMFCs to contend with PEMFCs for market viability, it is necessary to realize a competitive cell performance. This work demonstrates a new benchmark for a H2/O2 AEMFC with a peak power density of 1.4 W cm-2 at 60 °C. This was accomplished by taking a more precise look at balancing necessary membrane hydration while preventing electrode flooding, which somewhat surprisingly can occur both at the anode and the cathode. Specifically, radiation-grafted ETFE-based anion exchange membranes and anion exchange ionomer powder, functionalized with benchmark benzyltrimethylammonium groups, were utilized to examine the effects of the following parameters on AEMFC performance: feed gas flow rate, the use of hydrophobic vs. hydrophilic gas diffusion layers, and gas feed dew points.

  6. Multiphase Simulations and Design of Validation Experiments for Proton Exchange Membrane Fuel Cells

    DEFF Research Database (Denmark)

    Berning, Torsten

    2013-01-01

    Proton exchange membrane fuel cells directly convert into electricity the chemical energy of hydrogen and oxygen from air. The by-products are just water and waste heat. Depending on the operating conditions the water may be in the liquid or gas phase, and liquid water can hence plug the porous...

  7. Review of low pressure plasma processing of proton exchange membrane fuel cell electrocatalysts

    OpenAIRE

    Brault , Pascal

    2016-01-01

    Review article; International audience; The present review is describing recent advances in plasma deposition and treatment of low temperature proton exchange membrane fuel cells electrocatalysts. Interest of plasma processing for growth of platinum based, non-precious and metal free electrocatalysts is highlighted. Electrocatalysts properties are tentatively correlated to plasma parameters.

  8. Post-transfusion purpura treated with plasma exchange by haemonetics cell separator. A case report

    DEFF Research Database (Denmark)

    Laursen, B; Morling, N; Rosenkvist, J

    1978-01-01

    A case of post-transfusion purpura in a 61-year-old, multiparous female with a platelet alloantibody (anti-Zwa) in her serum is reported. The patient was successfully treated with plasma exchange by means of a Haemonetics 30 cell separator and corticosteroids. Compared with other therapeutic...

  9. Bromodeoxyuridine does not contribute to sister chromatid exchange events in normal or Bloom syndrome cells

    NARCIS (Netherlands)

    van Wietmarschen, Niek; Lansdorp, Peter M.

    2016-01-01

    Sister chromatid exchanges (SCEs) are considered sensitive indicators of genome instability. Detection of SCEs typically requires cells to incorporate bromodeoxyuridine (BrdU) during two rounds of DNA synthesis. Previous studies have suggested that SCEs are induced by DNA replication over

  10. Dual cell conductivity during ionic exchange processes: the intelligent transmitter EXA DC 400

    International Nuclear Information System (INIS)

    Mier, A.

    1997-01-01

    Why is differential conductivity important versus standard conductivity measurement? That entirely depends on the application. If we have a process where the conductivity changes ge.. Cation exchanger, then standard conductivity measurement is not appropriate. With dual cell conductivity we can rate the process and eliminate conductivity changes outside the process. Therefore we achieve more precise control or monitoring of that process. (Author)

  11. Post-transfusion purpura treated with plasma exchange by haemonetics cell separator. A case report

    DEFF Research Database (Denmark)

    Laursen, B; Morling, N; Rosenkvist, J

    1978-01-01

    A case of post-transfusion purpura in a 61-year-old, multiparous female with a platelet alloantibody (anti-Zwa) in her serum is reported. The patient was successfully treated with plasma exchange by means of a Haemonetics 30 cell separator and corticosteroids. Compared with other therapeutic meas...

  12. Model-based fault detection for proton exchange membrane fuel cell ...

    African Journals Online (AJOL)

    In this paper, an intelligent model-based fault detection (FD) is developed for proton exchange membrane fuel cell (PEMFC) dynamic systems using an independent radial basis function (RBF) networks. The novelty is that this RBF networks is used to model the PEMFC dynamic systems and residuals are generated based ...

  13. The Effect of Pulsatile Versus Nonpulsatile Blood Flow on Viscoelasticity and Red Blood Cell Aggregation in Extracorporeal Circulation.

    Science.gov (United States)

    Ahn, Chi Bum; Kang, Yang Jun; Kim, Myoung Gon; Yang, Sung; Lim, Choon Hak; Son, Ho Sung; Kim, Ji Sung; Lee, So Young; Son, Kuk Hui; Sun, Kyung

    2016-06-01

    Extracorporeal circulation (ECC) can induce alterations in blood viscoelasticity and cause red blood cell (RBC) aggregation. In this study, the authors evaluated the effects of pump flow pulsatility on blood viscoelasticity and RBC aggregation. Mongrel dogs were randomly assigned to two groups: a nonpulsatile pump group (n=6) or a pulsatile pump group (n=6). After ECC was started at a pump flow rate of 80 mL/kg/min, cardiac fibrillation was induced. Blood sampling was performed before and at 1, 2, and 3 hours after ECC commencement. To eliminate bias induced by hematocrit and plasma, all blood samples were adjusted to a hematocrit of 45% using baseline plasma. Blood viscoelasticity, plasma viscosity, hematocrit, arterial blood gas analysis, central venous O2 saturation, and lactate were measured. The blood viscosity and aggregation index decreased abruptly 1 hour after ECC and then remained low during ECC in both groups, but blood elasticity did not change during ECC. Blood viscosity, blood elasticity, plasma viscosity, and the aggregation index were not significantly different in the groups at any time. Hematocrit decreased abruptly 1 hour after ECC in both groups due to dilution by the priming solution used. After ECC, blood viscoelasticity and RBC aggregation were not different in the pulsatile and nonpulsatile groups in the adult dog model. Furthermore, pulsatile flow did not have a more harmful effect on blood viscoelasticity or RBC aggregation than nonpulsatile flow.

  14. Cytogenetic effects of grape extracts (Vitis vinifera) and polyphenols on mitomycin C-induced sister chromatid exchanges (SCEs) in human blood lymphocytes.

    Science.gov (United States)

    Stagos, Dimitrios; Spanou, Chrysa; Margariti, Maria; Stathopoulos, Constantinos; Mamuris, Zissis; Kazantzoglou, Georgios; Magiatis, Prokopios; Kouretas, Demetrios

    2007-06-27

    In the present study, the effects of extracts and polyphenol-rich fractions as well as monomer polyphenols identified in them, from both red and white grapes, on mitomycin C (MMC) induced sister chromatid exchanges (SCEs) in human peripheral blood lymphocytes were investigated. The grape extracts and two of the three polyphenol-rich fractions promoted MMC-induced SCEs at concentrations from 75 to 300 microg/mL. However, none of the extracts or fractions alone induced SCEs. Thus, these results suggest caution especially with regard to the use of grape extracts as dietary supplements. On the other hand, the fact that these extracts were not genotoxic alone may indicate a selective activity against genetically damaged cells. This is the first study regarding the clastogenic effects of grape extracts in human cells. Moreover, from the tested polyphenols, caffeic acid, gallic acid, and rutin hydrate enhanced MMC-induced clastogenicity, whereas ferulic acid, protocatechuic acid, (+)-catechin, (-)-epicatechin, and trans-resveratrol had no effect at concentrations between 5 and 100 microM. The differences in the chemical structures of the tested polyphenols may account for their differential effects on MMC clastogenicity.

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

    Science.gov (United States)

    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.

  16. Methylene blue modulates transendothelial migration of peripheral blood cells.

    Directory of Open Access Journals (Sweden)

    Isabella Werner

    Full Text Available Vasoplegia is a severe complication after cardiac surgery. Within the last years the administration of nitric oxide synthase inhibitor methylene blue (MB became a new therapeutic strategy. Our aim was to investigate the role of MB on transendothelial migration of circulating blood cells, the potential role of cyclic cGMP, eNOS and iNOS in this process, and the influence of MB on endothelial cell apoptosis. Human vascular endothelial cells (HuMEC-1 were treated for 30 minutes or 2 hours with different concentrations of MB. Inflammation was mimicked by LPS stimulation prior and after MB. Transmigration of PBMCs and T-Lymphocytes through the treated endothelial cells was investigated. The influence of MB upon the different subsets of PBMCs (Granulocytes, T- and B-Lymphocytes, and Monocytes was assessed after transmigration by means of flow-cytometry. The effect of MB on cell apoptosis was evaluated using Annexin-V and Propidium Iodide stainings. Analyses of the expression of cyclic cGMP, eNOS and iNOS were performed by means of RT-PCR and Western Blot. Results were analyzed using unpaired Students T-test. Analysis of endothelial cell apoptosis by MB indicated a dose-dependent increase of apoptotic cells. We observed time- and dose-dependent effects of MB on transendothelial migration of PBMCs. The prophylactic administration of MB led to an increase of transendothelial migration of PBMCs but not Jurkat cells. Furthermore, HuMEC-1 secretion of cGMP correlated with iNOS expression after MB administration but not with eNOS expression. Expression of these molecules was reduced after MB administration at protein level. This study clearly reveals that endothelial response to MB is dose- and especially time-dependent. MB shows different effects on circulating blood cell-subtypes, and modifies the release patterns of eNOS, iNOS, and cGMP. The transendothelial migration is modulated after treatment with MB. Furthermore, MB provokes apoptosis of endothelial

  17. Induced Pluripotent Stem Cell-Derived Red Blood Cells and Platelet Concentrates: From Bench to Bedside

    Directory of Open Access Journals (Sweden)

    Daniele Focosi

    2017-12-01

    Full Text Available Red blood cells and platelets are anucleate blood components indispensable for oxygen delivery and hemostasis, respectively. Derivation of these blood elements from induced pluripotent stem (iPS cells has the potential to develop blood donor-independent and genetic manipulation-prone products to complement or replace current transfusion banking, also minimizing the risk of alloimmunization. While the production of erythrocytes from iPS cells has challenges to overcome, such as differentiation into adult-type phenotype that functions properly after transfusion, platelet products are qualitatively and quantitatively approaching a clinically-applicable level owing to advances in expandable megakaryocyte (MK lines, platelet-producing bioreactors, and novel reagents. Guidelines that assure the quality of iPS cells-derived blood products for clinical application represent a novel challenge for regulatory agencies. Considering the minimal risk of tumorigenicity and the expected significant demand of such products, ex vivo production of iPS-derived blood components can pave the way for iPS translation into the clinic.

  18. Induced Pluripotent Stem Cell-Derived Red Blood Cells and Platelet Concentrates: From Bench to Bedside.

    Science.gov (United States)

    Focosi, Daniele; Amabile, Giovanni

    2017-12-27

    Red blood cells and platelets are anucleate blood components indispensable for oxygen delivery and hemostasis, respectively. Derivation of these blood elements from induced pluripotent stem (iPS) cells has the potential to develop blood donor-independent and genetic manipulation-prone products to complement or replace current transfusion banking, also minimizing the risk of alloimmunization. While the production of erythrocytes from iPS cells has challenges to overcome, such as differentiation into adult-type phenotype that functions properly after transfusion, platelet products are qualitatively and quantitatively approaching a clinically-applicable level owing to advances in expandable megakaryocyte (MK) lines, platelet-producing bioreactors, and novel reagents. Guidelines that assure the quality of iPS cells-derived blood products for clinical application represent a novel challenge for regulatory agencies. Considering the minimal risk of tumorigenicity and the expected significant demand of such products, ex vivo production of iPS-derived blood components can pave the way for iPS translation into the clinic.

  19. Investigation of water distribution in proton exchange membrane fuel cells via Terahertz imaging

    International Nuclear Information System (INIS)

    Thamboon, P.; Buaphad, P.; Thongbai, C.; Saisud, J.; Kusoljariyakul, K.; Rhodes, M.W.; Vilaithong, T.

    2011-01-01

    Coherent transition radiation in a THz regime generated from a femtosecond electron bunch is explored for its potential use in imaging applications. Due to water sensitivity, the THz imaging experiment is performed on a proton exchange membrane fuel cell (PEMFC) to assess the ability to quantify water in the flow field of the cell. In this investigation, the PEMFC design and the experimental setup for the THz imaging is described. The results of the THz images in the flow field are also discussed.

  20. Proton Exchange Membrane Fuel Cell Modelling Using Moving Least Squares Technique

    Directory of Open Access Journals (Sweden)

    Radu Tirnovan

    2009-07-01

    Full Text Available Proton exchange membrane fuel cell, with low polluting emissions, is a great alternative to replace the traditional electrical power sources for automotive applications or for small stationary consumers. This paper presents a numerical method, for the fuel cell modelling, based on moving least squares (MLS. Experimental data have been used for developing an approximated model of the PEMFC function of the current density, air inlet pressure and operating temperature of the fuel cell. The method can be applied for modelling others fuel cell sub-systems, such as the compressor. The method can be used for off-line or on-line identification of the PEMFC stack.

  1. Manipulation of red blood cells with electric field

    Science.gov (United States)

    Saboonchi, Hossain; Esmaeeli, Asghar

    2009-11-01

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

  2. White blood cell counting on smartphone paper electrochemical sensor.

    Science.gov (United States)

    Wang, Xinhao; Lin, Guohong; Cui, Guangzhe; Zhou, Xiangfei; Liu, Gang Logan

    2017-04-15

    White blood cell (WBC) analysis provides rich information in rapid diagnosis of acute bacterial and viral infections as well as chronic disease management. For patients with immune deficiency or leukemia WBC should be persistently monitored. Current WBC counting method relies on bulky instrument and trained personnel and is time consuming. Rapid, low-cost and portable solution is in highly demand for point of care test. Here we demonstrate a label-free smartphone based electrochemical WBC counting device on microporous paper with patterned gold microelectrodes. WBC separated from whole blood was trapped by the paper with microelectrodes. WBC trapped on the paper leads to the ion diffusion blockage on microelectrodes, therefore cell concentration is determined by peak current on the microelectrodes measured by a differential pulse voltammeter and the quantitative results are collected by a smartphone wirelessly within 1min. We are able to rapidly quantify WBC concentrations covering the common physiological and pathological range (200-20000μL -1 ) with only 10μL sample and high repeatability as low as 10% in CoV (Coefficient of Variation). The unique smartphone paper electrochemical sensor ensures fast cell quantification to achieve rapid and low-cost WBC analysis at the point-of-care under resource limited conditions. Copyright © 2016. Published by Elsevier B.V.

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

    Science.gov (United States)

    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

  4. Modeling the ischemic blood-brain barrier; the effects of oxygen-glucose deprivation (OGD) on endothelial cells in culture

    DEFF Research Database (Denmark)

    Tornabene, Erica; Helms, Hans Christian Cederberg; Berndt, Philipp

    their passage through the capillary endothelium. An ischemic insult and the subsequent restoration of blood flow, defined as reperfusion, dramatically impair the BBB integrity, resulting in increased BBB permeability, modified transport pathways, edema and tissue damage. A deeper understanding of the permeation......Introduction - The blood-brain barrier (BBB) is a physical, transport and metabolic barrier which plays a key role in preventing uncontrolled exchanges between blood and brain, ensuring an optimal environment for neurons activity. This extent interface is created by the endothelial cells forming...... the wall of brain capillaries. The restrictive nature of the BBB is due to the tight junctions (TJs), which seal the intercellular clefts, limiting the paracellular diffusion, efflux transporters, which extrude xenobiotics, and metabolizing enzymes, which may break down or convert molecules during...

  5. Monolithic Chip for High-throughput Blood Cell Depletion to Sort Rare Circulating Tumor Cells.

    Science.gov (United States)

    Fachin, Fabio; Spuhler, Philipp; Martel-Foley, Joseph M; Edd, Jon F; Barber, Thomas A; Walsh, John; Karabacak, Murat; Pai, Vincent; Yu, Melissa; Smith, Kyle; Hwang, Henry; Yang, Jennifer; Shah, Sahil; Yarmush, Ruby; Sequist, Lecia V; Stott, Shannon L; Maheswaran, Shyamala; Haber, Daniel A; Kapur, Ravi; Toner, Mehmet

    2017-09-07

    Circulating tumor cells (CTCs) are a treasure trove of information regarding the location, type and stage of cancer and are being pursued as both a diagnostic target and a means of guiding personalized treatment. Most isolation technologies utilize properties of the CTCs themselves such as surface antigens (e.g., epithelial cell adhesion molecule or EpCAM) or size to separate them from blood cell populations. We present an automated monolithic chip with 128 multiplexed deterministic lateral displacement devices containing ~1.5 million microfabricated features (12 µm-50 µm) used to first deplete red blood cells and platelets. The outputs from these devices are serially integrated with an inertial focusing system to line up all nucleated cells for multi-stage magnetophoresis to remove magnetically-labeled white blood cells. The monolithic CTC-iChip enables debulking of blood samples at 15-20 million cells per second while yielding an output of highly purified CTCs. We quantified the size and EpCAM expression of over 2,500 CTCs from 38 patient samples obtained from breast, prostate, lung cancers, and melanoma. The results show significant heterogeneity between and within single patients. Unbiased, rapid, and automated isolation of CTCs using monolithic CTC-iChip will enable the detailed measurement of their physicochemical and biological properties and their role in metastasis.

  6. Clustering of red blood cells using digital holographic microscopy

    Science.gov (United States)

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

    2017-05-01

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

  7. Steady state peripheral blood provides cells with functional and metabolic characteristics of real hematopoietic stem cells.

    Science.gov (United States)

    Bourdieu, Antonin; Avalon, Maryse; Lapostolle, Véronique; Ismail, Sadek; Mombled, Margaux; Debeissat, Christelle; Guérinet, Marianne; Duchez, Pascale; Chevaleyre, Jean; Vlaski-Lafarge, Marija; Villacreces, Arnaud; Praloran, Vincent; Ivanovic, Zoran; Brunet de la Grange, Philippe

    2018-01-01

    Hematopoietic stem cells (HSCs), which are located in the bone marrow, also circulate in cord and peripheral blood. Despite high availability, HSCs from steady state peripheral blood (SSPB) are little known and not used for research or cell therapy. We thus aimed to characterize and select HSCs from SSPB by a direct approach with a view to delineating their main functional and metabolic properties and the mechanisms responsible for their maintenance. We chose to work on Side Population (SP) cells which are highly enriched in HSCs in mouse, human bone marrow, and cord blood. However, no SP cells from SSBP have as yet been characterized. Here we showed that SP cells from SSPB exhibited a higher proliferative capacity and generated more clonogenic progenitors than non-SP cells in vitro. Furthermore, xenotransplantation studies on immunodeficient mice demonstrated that SP cells are up to 45 times more enriched in cells with engraftment capacity than non-SP cells. From a cell regulation point of view, we showed that SP activity depended on O 2 concentrations close to those found in HSC niches, an effect which is dependent on both hypoxia-induced factors HIF-1α and HIF-2α. Moreover SP cells displayed a reduced mitochondrial mass and, in particular, a lower mitochondrial activity compared to non-SP cells, while they exhibited a similar level of glucose incorporation. These results provided evidence that SP cells from SSPB displayed properties of very primitive cells and HSC, thus rendering them an interesting model for research and cell therapy. © 2017 Wiley Periodicals, Inc.

  8. Hubungan Antara Red Blood Cell Count (Rbc) Dan Retinopati Diabetik Pada Pasien Diabetes Melitus Tipe 2

    OpenAIRE

    Irmayani

    2016-01-01

    Background: Diabetic retinopathy is main complications of diabetes. Some studies suggest a relation between red blood cell count (RBC) and diabetic retinopathy. Diabetic retinopathy is diagnosed with funduscopic examination, while red blood cell count can be seen from the peripheral blood examination, with the result is a relation of a decreased red blood cell count with diabetic retinopathy. Objective: To determine the relation between RBC count and diabetic retinopathy in diabetic type...

  9. Blood Tests

    Science.gov (United States)

    ... your blood, as discussed in the following paragraphs. Red Blood Cells Red blood cells carry oxygen from ... leaks out, and its levels in your blood rise. For example, blood levels of troponin rise when ...

  10. 3D morphometry of red blood cells by digital holography.

    Science.gov (United States)

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

    2014-12-01

    Three dimensional (3D) morphometric analysis of flowing and not-adherent cells is an important aspect for diagnostic purposes. However, diagnostics tools need to be quantitative, label-free and, as much as possible, accurate. Recently, a simple holographic approach, based on shape from silhouette algorithm, has been demonstrated for accurate calculation of cells biovolume and displaying their 3D shapes. Such approach has been adopted in combination with holographic optical tweezers and successfully applied to cells with convex shape. Nevertheless, unfortunately, the method fails in case of specimen with concave surfaces. Here, we propose an effective approach to achieve correct 3D shape measurement that can be extended in case of cells having concave surfaces, thus overcoming the limit of the previous technique. We prove the new procedure for healthy red blood cells (RBCs) (i.e., discocytes) having a concave surface in their central region. Comparative analysis of experimental results with a theoretical 3D geometrical model of RBC is discussed in order to evaluate accuracy of the proposed approach. Finally, we show that the method can be also useful to classify, in terms of morphology, different varieties of RBCs. © 2014 International Society for Advancement of Cytometry.

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

    International Nuclear Information System (INIS)

    Benarroz, Monica Oliveira; Fonseca, Adenilson de Souza da; Bernardo-Filho, Mario; Geller, Mauro; Presta, Giuseppe Antonio

    2008-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2008-12-15

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

  13. Prompt cytomolecular identification of chromosome aberration in irradiated blood cells

    Directory of Open Access Journals (Sweden)

    Seyed Akbar Moosavi

    2017-02-01

    Full Text Available Background: understanding the genomic alteration induced by ionizing radiation still remains to be a methodological challenge in genetic field. The energy released from this type of radiation can potentially causes structural and numerical alterations in lymphocytes, which in turn converts them into abnormal tumor cells. Chromosomal abnormalities associated with specific type of hematological malignancies are determinant factors in evaluation of radiation dose and its potential in harming the body. None the less early detection of chromosomal aberration (CA is crucial in prognosis and selection of therapy for the people exposed to irradiations. The aim of this study was to explore a swift and accurate genetic test that identifies CAs in radiologist exposed to X-rays. In addition synergistic effect of other clastogens in irradiated workers was also evaluated. Material and methods: thirty four heparinized blood samples were obtained from radiology workers exposed to X-rays. Blood samples were cultured in RPMI 1640 and F-10 Medias with and without PHA stimulation. Lymphocytes were harvested, separated and arrested at metaphase and their chromosomes were analyzed by solid and G-Banding techniques. Lymphocytic CA was also analyzed through whole chromosome painting FISH. Results: of the 37 blood sample from workers, 60% had various structural aberrations in which both the frequency and type of CAs were intensified among tobacco smokers. Conclusion: the results did not show any significant differences between the genders but other carcinogen like smoking can significantly increases the rate of CAs

  14. Removal of Plasmodium falciparum-infected red blood cells from whole blood by leukoreduction filters.

    Science.gov (United States)

    Cardo, Lisa J; Salata, Jeanne; Wilder, Donna

    2009-02-01

    There has been an unexplained decrease in the incidence of transfusion-transmitted malaria in recent years. The decrease in incidence has paralleled the increasing use of leukoreduction filters. Malaria-infected red blood cells (RBCs) share surface characteristics of hemoglobin S-containing cells. Because units collected from donors with sickle trait do not filter optimally due to adherence of RBCs to the filters, the possibility that malaria-infected RBCs may also adhere to filters was investigated. Malaria-infected whole blood or calcium ionophore (A25187)-treated and control RBCs were filtered with leukoreduction filters. Quantitation of malaria-infected RBCs before and after filtration was performed by flow cytometry to determine the presence of DNA within RBCs, indicating malaria infection. Annexin V binding was also determined before and after filtration of RBCs treated with A25187. Immediately after filtration, filters were fixed and examined by scanning and transmission electron microscopy. There were at least three configurations of adherence of malaria-infected RBCs demonstrated within the filters. The first was direct adherence of infected RBCs to filter fibers; the second involved adherence of malaria-infected RBCs to platelets, which were adherent to filter fibers; and the third was adherence of infected RBCs to other RBCs. Filtration also resulted in preferential removal of phosphatidylserine (PS)-expressing cells as seen by the reduction of annexin V binding after filtration. This was further confirmed by electron micrographic examination of the filters in which untreated RBCs sit within the filter resting on top of filter fibers; however, calcium ionophore-treated RBCs are seen to cling tightly to the fibers. PS expression by RBCs leads to their adherence within leukoreduction filters. Malaria-infected RBCs are retained via more than one mechanism. The efficiency of removal requires further study.

  15. New load cycling strategy for enhanced durability of high temperature proton exchange membrane fuel cell

    DEFF Research Database (Denmark)

    Thomas, Sobi; Jeppesen, Christian; Steenberg, Thomas

    2017-01-01

    The objective of this paper is to develop a new operational strategy to increase the lifetime of a high temperature proton exchange membrane (HT-PEMFCs) fuel cell system by using load cycling patterns to reduce the phosphoric acid loss from the fuel cell. Four single cells were operated under.......8 Acm-2 for the higher end, were selected for the load cycling operation. The relaxation time, which is the period of time spent at low current density operation, is varied to understand how the performance over prolonged period behaves. The duration of the high current density operation is selected...... based on the relaxation time in order to have the same average current density of (0.55 Acm-2 ) for all the cells. Cell 5, with a relaxation time of 2 min performs best and shows lower degradation rate of 36 μVh-1 compared to other load cycling cells with smaller relaxation times. The cell operated...

  16. Efficacy and Safety of Manual Partial Red Cell Exchange in the Management of Severe Complications of Sickle Cell Disease in a Developing Country

    Directory of Open Access Journals (Sweden)

    B. F. Faye

    2017-01-01

    Full Text Available Introduction. The realization of red cell exchange (RCE in Africa faces the lack of blood, transfusion safety, and equipment. We evaluated its efficacy and safety in severe complications of sickle cell disease. Patients and Method. Manual partial RCE was performed among sickle cell patients who had severe complications. Efficacy was evaluated by clinical evolution, blood count, and electrophoresis of hemoglobin. Safety was evaluated on adverse effects, infections, and alloimmunization. Results. We performed 166 partial RCE among 44 patients including 41 homozygous (SS and 2 heterozygous composites SC and 1 S/β0-thalassemia. The mean age was 27.9 years. The sex ratio was 1.58. The regression of symptoms was complete in 100% of persistent vasoocclusive crisis and acute chest syndrome, 56.7% of intermittent priapism, and 30% of stroke. It was partial in 100% of leg ulcers and null in acute priapism. The mean variations of hemoglobin and hematocrit rate after one procedure were, respectively, +1.4 g/dL and +4.4%. That of hemoglobin S after 2 consecutive RCE was −60%. Neither alloimmunization nor viral seroconversion was observed. Conclusion. This work shows the feasibility of manual partial RCE in a low-resource setting and its efficacy and safety during complications of SCD outside of acute priapism.

  17. Efficacy and Safety of Manual Partial Red Cell Exchange in the Management of Severe Complications of Sickle Cell Disease in a Developing Country

    Science.gov (United States)

    Sow, D.; Seck, M.; Dieng, N.; Toure, S. A.; Gadji, M.; Senghor, A. B.; Gueye, Y. B.; Sy, D.; Sall, A.; Dieye, T. N.; Toure, A. O.; Diop, S.

    2017-01-01

    Introduction The realization of red cell exchange (RCE) in Africa faces the lack of blood, transfusion safety, and equipment. We evaluated its efficacy and safety in severe complications of sickle cell disease. Patients and Method Manual partial RCE was performed among sickle cell patients who had severe complications. Efficacy was evaluated by clinical evolution, blood count, and electrophoresis of hemoglobin. Safety was evaluated on adverse effects, infections, and alloimmunization. Results We performed 166 partial RCE among 44 patients including 41 homozygous (SS) and 2 heterozygous composites SC and 1 S/β0-thalassemia. The mean age was 27.9 years. The sex ratio was 1.58. The regression of symptoms was complete in 100% of persistent vasoocclusive crisis and acute chest syndrome, 56.7% of intermittent priapism, and 30% of stroke. It was partial in 100% of leg ulcers and null in acute priapism. The mean variations of hemoglobin and hematocrit rate after one procedure were, respectively, +1.4 g/dL and +4.4%. That of hemoglobin S after 2 consecutive RCE was −60%. Neither alloimmunization nor viral seroconversion was observed. Conclusion This work shows the feasibility of manual partial RCE in a low-resource setting and its efficacy and safety during complications of SCD outside of acute priapism. PMID:28584527

  18. Evaluation of a Centrifuged Double Y-Shape Microfluidic Platform for Simple Continuous Cell Environment Exchange

    Directory of Open Access Journals (Sweden)

    Akihiro Hattori

    2012-01-01

    Full Text Available We have demonstrated the efficacy of a microfluidic medium exchange method for single cells using passive centrifugal force of a rotating microfluidic-chip based platform. At the boundary of two laminar flows at the gathering area of two microfluidic pathways in a Y-shape, the cells were successfully transported from one laminar flow to the other, without mixing the two microfluidic mediums of the two laminar flows during cell transportation, within 5 s with 1 g (150 rpm to 36.3 g (900 rpm acceleration, with 93.5% efficiency. The results indicate that this is one of the most simple and precise tools for exchanging medium in the shortest amount of time.

  19. Amyotrophic lateral sclerosis multiprotein biomarkers in peripheral blood mononuclear cells.

    Directory of Open Access Journals (Sweden)

    Giovanni Nardo

    Full Text Available Amyotrophic lateral sclerosis (ALS is a fatal progressive motor neuron disease, for which there are still no diagnostic/prognostic test and therapy. Specific molecular biomarkers are urgently needed to facilitate clinical studies and speed up the development of effective treatments.We used a two-dimensional difference in gel electrophoresis approach to identify in easily accessible clinical samples, peripheral blood mononuclear cells (PBMC, a panel of protein biomarkers that are closely associated with ALS. Validations and a longitudinal study were performed by immunoassays on a selected number of proteins. The same proteins were also measured in PBMC and spinal cord of a G93A SOD1 transgenic rat model. We identified combinations of protein biomarkers that can distinguish, with high discriminatory power, ALS patients from healthy controls (98%, and from patients with neurological disorders that may resemble ALS (91%, between two levels of disease severity (90%, and a number of translational biomarkers, that link responses between human and animal model. We demonstrated that TDP-43, cyclophilin A and ERp57 associate with disease progression in a longitudinal study. Moreover, the protein profile changes detected in peripheral blood mononuclear cells of ALS patients are suggestive of possible intracellular pathogenic mechanisms such as endoplasmic reticulum stress, nitrative stress, disturbances in redox regulation and RNA processing.Our results indicate that PBMC multiprotein biomarkers could contribute to determine amyotrophic lateral sclerosis diagnosis, differential diagnosis, disease severity and progression, and may help to elucidate pathogenic mechanisms.

  20. The DNA methylome of human peripheral blood mononuclear cells.

    Directory of Open Access Journals (Sweden)

    Yingrui Li

    2010-11-01

    Full Text Available DNA methylation plays an important role in biological processes in human health and disease. Recent technological advances allow unbiased whole-genome DNA methylation (methylome analysis to be carried out on human cells. Using whole-genome bisulfite sequencing at 24.7-fold coverage (12.3-fold per strand, we report a comprehensive (92.62% methylome and analysis of the unique sequences in human peripheral blood mononuclear cells (PBMC from the same Asian individual whose genome was deciphered in the YH project. PBMC constitute an important source for clinical blood tests world-wide. We found that 68.4% of CpG sites and 80% displayed allele-specific expression (ASE. These data demonstrate that ASM is a recurrent phenomenon and is highly correlated with ASE in human PBMCs. Together with recently reported similar studies, our study provides a comprehensive resource for future epigenomic research and confirms new sequencing technology as a paradigm for large-scale epigenomics studies.

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

    Directory of Open Access Journals (Sweden)

    Kimberly Sanford

    2017-07-01

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

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

    Science.gov (United States)

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

    2017-06-01

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

  3. Survival of red blood cells after transfusion: processes and consequences

    Directory of Open Access Journals (Sweden)

    Giel eBosman

    2013-12-01

    Full Text Available The currently available data suggest that efforts towards improving the quality of red blood cell (RBC blood bank products should concentrate on: (1 preventing the removal of a considerable fraction of the transfused RBCs that takes place within the first hours after transfusion; (2 minimizing the interaction of the transfused RBCs with the patient's immune system. These issues are important in reducing the number and extent of the damaging side effects of transfusions, such as generation of alloantibodies and autoantibodies and iron accumulation, especially in transfusion-dependent patients. Thus, it becomes important for blood bank research not only to assess the classical RBC parameters for quality control during storage, but even more so to identify the parameters that predict RBC survival, function and behaviour in the patient after transfusion. These parameters are likely to result from elucidation of the mechanisms that underly physiological RBC aging in vivo, and that lead to the generation of senescent cell antigens and the accumulation of damaged molecules in vesicles. Also, study of RBC pathology-related mechanisms, such as encountered in various hemoglobinopathies and membranopathies, may help to elucidate the mechanisms underlying a storage-associated increase in susceptibility to physiological stress conditions. Recent data indicate that a combination of new approaches in vitro to mimick RBC behaviour in vivo, the growing knowledge of the signaling networks that regulate RBC structure and function, and the rapidly expanding set of proteomic and metabolomic data, will be instrumental to identify the storage-associated processes that control RBC survival after transfusion.

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

    Directory of Open Access Journals (Sweden)

    Zhijing Liu

    2015-01-01

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

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

    Science.gov (United States)

    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.

  6. Absence of transepithelial anion exchange by rabbit OMCD: Evidence against reversal of cell polarity

    Energy Technology Data Exchange (ETDEWEB)

    Hayashi, Matsuhiko; Schuster, V.L.; Stokes, J.B. (Univ. of Iowa College of Medicine, Iowa City (USA))

    1988-08-01

    In the rabbit cortical collecting duct (CCD), Cl tracer crosses the epithelium predominantly via an anion exchange system that operates in either a Cl-Cl or Cl-HCO{sub 3} exchange mode. In the present study, the authors used the {sup 36}Cl lumen-to-bath rate coefficient (K{sub Cl}, nm/s), a sensitive measurement of CCD transepithelial anion transport, to investigate the nature of Cl transport in the medullary collecting duct dissected from inner stripe, outer medulla (OMCD). The K{sub Cl} in OMCD perfused and bathed in HCO{sub 3}-Ringer solution was low and similar to that value observed in the CCD when anion exchange is inhibited and Cl permeates the epithelium by diffusion. To test the hypothesis that metabolic alkalosis could reverse the polarity of intercalated cells and thus induce an apical Cl-HCO{sub 3} exchanger in H{sup +}-secreting OMCD cells, they measured K{sub Cl} in OMCD from rabbits make alkalotic by deoxycorticosterone and furosemide. Although the base-line K{sub Cl} was slightly higher than in OMCD from control rabbits, the value was still far lower than the K{sub Cl} under comparable conditions in CCD. They conclude (1) Cl transport across the MCD by anion exchange is immeasurably low or nonexistent; (2) unlike the CCD, Cl transport in OMCD is not responsive to cAMP; and (3) metabolic alkalosis does not induce an apical anion exchanger in OMCD, i.e., does not cause epithelial polarity reversal.

  7. Cross-linked poly(arylene ether ketone) proton exchange membranes with high ion exchange capacity for fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, S.; Hai, S.D.; Kim, D. [School of Chemical Engineering, Sungkyunkwan University, Suwon, Kyunggi (Korea, Republic of)

    2012-08-15

    Sulfonated poly(arylene ether ketone) (SPAEK) possessing the pendant carboxylic acid groups was synthesized. The carboxylic acid groups of SPAEK were reacted with a cross-linking reagent to prepare a cross-linked membrane with a high ion exchange capacity (IEC), a high oxidative stability, and an excellent mechanical strength. The cross-linking hindered the mobility of the polymer chains and thus strongly affected the water uptake and the methanol permeability of the membranes. Also, as the cross-linker used in this study bore sulfonic acid groups, cross-linking did not lead to a noticeable loss of the proton conductivity. The cross-linked SPAEK membrane with 20% cross-linking density, CSPAEK-20% membrane, exhibited a high proton conductivity of 0.045 S cm{sup -1} associated with a high IEC value of 1.78 mmol g{sup -1} but a low methanol permeability of 4.3 x 10{sup -7} cm{sup 2} s{sup -1}. The CSPAEK-20% membrane also showed excellent cell performance and oxidation resistance. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  8. Evidence for the exchange of blood parasites between North America and the Neotropics in blue-winged teal (Anas discors)

    Science.gov (United States)

    Ramey, Andy M.; Reed, John; Walther, Patrick; Link, Paul; Schmutz, Joel A.; Douglas, David; Stallknecht, David E.; Soos, Catherine

    2016-01-01

    Blue-winged teal (Anas discors) are abundant, small-bodied dabbling ducks that breed throughout the prairies of the northcentral USA and central Canada and that winter in the southern USA and northern Neotropics. Given the migratory tendencies of this species, it is plausible that blue-winged teal may disperse avian pathogens, such as parasites causing avian malaria, between spatially distant areas. To test the hypothesis that blue-winged teal play a role in the exchange of blood parasites between North America and areas further south, we collected information on migratory tendencies of this species and sampled birds at spatially distant areas during breeding and non-breeding periods to diagnose and genetically characterize parasitic infections. Using a combination of band recovery data, satellite telemetry, molecular diagnostics, and genetic analyses, we found evidence for (1) migratory connectivity of blue-winged teal between our sampling locations in the Canadian prairies and along the US Gulf Coast with areas throughout the northern Neotropics, (2) parasite acquisition at both breeding and non-breeding areas, (3) infection of blue-winged teal sampled in Canada and the USA withPlasmodium parasite lineages associated with the Neotropics, and (4) infection of blue-winged teal with parasites that were genetically related to those previously reported in waterfowl in both North America and South America. Collectively, our results suggest that blue-winged teal likely play a role in the dispersal of blood parasites between the Neotropics and North America, and therefore, the targeting of this species in surveillance programs for the early detection of Neotropical-origin avian pathogens in the USA may be informative.

  9. Evidence for the exchange of blood parasites between North America and the Neotropics in blue-winged teal (Anas discors).

    Science.gov (United States)

    Ramey, Andrew M; Reed, John A; Walther, Patrick; Link, Paul; Schmutz, Joel A; Douglas, David C; Stallknecht, David E; Soos, Catherine

    2016-10-01

    Blue-winged teal (Anas discors) are abundant, small-bodied dabbling ducks that breed throughout the prairies of the northcentral USA and central Canada and that winter in the southern USA and northern Neotropics. Given the migratory tendencies of this species, it is plausible that blue-winged teal may disperse avian pathogens, such as parasites causing avian malaria, between spatially distant areas. To test the hypothesis that blue-winged teal play a role in the exchange of blood parasites between North America and areas further south, we collected information on migratory tendencies of this species and sampled birds at spatially distant areas during breeding and non-breeding periods to diagnose and genetically characterize parasitic infections. Using a combination of band recovery data, satellite telemetry, molecular diagnostics, and genetic analyses, we found evidence for (1) migratory connectivity of blue-winged teal between our sampling locations in the Canadian prairies and along the US Gulf Coast with areas throughout the northern Neotropics, (2) parasite acquisition at both breeding and non-breeding areas, (3) infection of blue-winged teal sampled in Canada and the USA with Plasmodium parasite lineages associated with the Neotropics, and (4) infection of blue-winged teal with parasites that were genetically related to those previously reported in waterfowl in both North America and South America. Collectively, our results suggest that blue-winged teal likely play a role in the dispersal of blood parasites between the Neotropics and North America, and therefore, the targeting of this species in surveillance programs for the early detection of Neotropical-origin avian pathogens in the USA may be informative.

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

    Directory of Open Access Journals (Sweden)

    V. V. Moroz

    2011-01-01

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

  11. In vivo mutations in human blood cells: Biomarkers for molecular epidemiology

    Energy Technology Data Exchange (ETDEWEB)

    Albertini, R.J.; Branda, R.F.; O' Neill, J.P. (Univ. of Vermont, Burlington (United States)); Nicklas, J.A.; Fuscoe, J.C. (Environmental Health Research and Testing, Inc., Research Triangle Park, NC (United States)); Skopek, T.R. (Univ. of North Carolina, Chapel Hill (United States))

    1993-03-01

    Mutations arising in vivo in recorder genes of human blood cells provide biomarkers for molecular epidemiology by serving as surrogates for cancer-causing genetic changes. Current markers include mutations of the glycophorin-A (GPA) or hemoglobin (Hb) genes, measured in red blood cells, or mutations of the hypoxanthine-guanine phosphoribosyltransferase (hprt) or HLA genes, measured in T-lymphocytes. Mean mutant frequencies (variant frequencies) for normal young adults are approximately: Hb (4 [times] 10[sup [minus]8]) < hprt (5 [times] 10[sup [minus]6]) = GPA (10 [times] 10[sup [minus]6]) < HLA (30 [times] 10[sup [minus]6]). Mutagen-exposed individuals show decided elevations. Molecular mutational spectra are also being defined. For the hprt marker system, about 15% of background mutations are gross structural alterations of the hprt gene (e.g., deletions); the remainder are point mutations (e.g., base substitutions or frameshifts). Ionizing radiations result in dose-related increases in total gene deletions. Large deletions may encompass several megabases as shown by co-deletions of linked markers. Possible hprt spectra for defining radiation and chemical exposures are being sought. In addition to their responsiveness to environmental mutagens/carcinogens, three additional findings suggest that the in vivo recorder mutations are relevant in vivo surrogates for cancer mutations. First, a large fraction of GPA and HLA mutations show exchanges due to homologous recombination, an important mutational event in cancer. Second, hprt mutations arise preferentially in dividing T-cells, which can accumulate additional mutations in the same clone, reminiscent of the multiple hits required in the evolution of malignancy. Finally, fetal hprt mutations frequently have characteristic deletions of hprt exons 2 and 3, which appear to be mediated by the VDJ recombinase that rearranges the T-cell receptor genes during thymic ontogeny. 60 refs., 3 tabs.

  12. [Blood transfusion assessment to 112 homozygous sickle-cell disease patients in university hospital of Brazzaville].

    Science.gov (United States)

    Dokekias, A Elira; Ossini, L Ngolet; Tsiba, F O Atipo; Malanda, F; Koko, I; De Montalembert, M

    2009-01-01

    Homozygous, sickle-cell disease (SCD) is responsible for acute complication, especially anaemic crisis and special situation such as acute chest syndrome, stroke and acute priapism. Pregnancy sickle-cell disease presents high risk for the mother and the fetus. In these indications, blood transfusion is the main therapy aiming to reduce anaemia in order to restore hemoglobin's rate or to increase normal Hb proportion. This study aims to assess the short-term efficiency of the red cell transfusion in SCD homozygous form. One hundred and twelve homozygous sickle-cell patients were enrolled in this prospective study: 59 females and 53 males, median age is 21,8 years (extremes: 2 and 45 years). These patients are mostly with very low income. Two groups of patients are included in this study. In the first group, patients present acute anemia crisis caused by infections disease (malaria, bacterial infections). In the second group (20 cases), SCD patients have particularly situations: pregnancy (10 cases); stroke (six cases); cardiac failure (two cases) and priapism (two cases). Transfusion treatment in first group is simple regimen. Transfusion of EC increased median Hb level at 2,9 g/dl (extremes: 1,1 and 4,7). In the second group of patients, 16 cases were transfused by manual partial exchange (1-3) and four patients received simple regimen of transfusion. Median Hb level was 3,1g/dl (extremes: 2,4-4,9 g/dl). HbS percentage reduction was after PTE between -30 and -66,8% (median: -52,6%). According to our diagnostic possibilities (blood serologic test), we have not found any contamination by HIV, HBV and HCV (virus).

  13. Mathematical modeling of water mass balance for proton exchange membrane fuel cell

    International Nuclear Information System (INIS)

    Wan Ramli Wan Daud; Kamaruzzaman Sopian; Jaafar Sahari; Nik Suhaimi Mat Hassan

    2006-01-01

    Gas and water management are key to achieving good performance from a proton exchange membrane fuel cell (PEMFC) stack. Water plays a critical role in PEMFC. The proton conductivity is increase with the water content. In order to achieve enough hydration, water is normally introduced into the cell externally by a variety of methods such as liquid injection, steam introduction, and humidification of reactants by passing them through humidifiers before entering the cell. In this paper, mathematical modeling of water mass balance for PEMFC at anode and cathode side are proposed by using external humidification and assume that steady state, constant pressure, constant temperature and gases distribution are uniform

  14. The mass balance of a Proton Exchange Membrane Fuel Cell (PEMFC)

    International Nuclear Information System (INIS)

    Miloud, S.; Kamaruzzaman Sopian; Wan Ramli Wan Daud

    2006-01-01

    A Proton Exchange Membrane Fuel Cell (PEMFC), operating at low temperature uses a simple chemical process to combine hydrogen and oxygen into water, producing electric current and heat during the electrochemical reaction. This work concern on the theoretical consideration of the mass balance has been evaluated to predict the mass flow rate of the both gases (hydrogen/oxygen), the water mass balance, and the heat transfer in order to design a single cell PEMFC stack with a better flow field distributor on the performance of Polymer Electrolyte membrane fuel cells

  15. Automated exchange transfusion and exchange rate.

    Science.gov (United States)

    Funato, M; Shimada, S; Tamai, H; Taki, H; Yoshioka, Y

    1989-10-01

    An automated blood exchange transfusion (BET) with a two-site technique has been devised by Goldmann et al and by us, using an infusion pump. With this method, we successfully performed exchange transfusions 189 times in the past four years on 110 infants with birth weights ranging from 530 g to 4,000 g. The exchange rate by the automated method was compared with the rate by Diamond's method. Serum bilirubin (SB) levels before and after BET and the maximal SB rebound within 24 hours after BET were: 21.6 +/- 2.4, 11.5 +/- 2.2, and 15.0 +/- 1.5 mg/dl in the automated method, and 22.0 +/- 2.9, 11.2 +/- 2.5, and 17.7 +/- 3.2 mg/dl in Diamond's method, respectively. The result showed that the maximal rebound of the SB level within 24 hours after BET was significantly lower in the automated method than in Diamond's method (p less than 0.01), though SB levels before and after BET were not significantly different between the two methods. The exchange rate was also measured by means of staining the fetal red cells (F cells) both in the automated method and in Diamond's method, and comparing them. The exchange rate of F cells in Diamond's method went down along the theoretical exchange curve proposed by Diamond, while the rate in the automated method was significantly better than in Diamond's, especially in the early stage of BET (p less than 0.01). We believe that the use of this automated method may give better results than Diamond's method in the rate of exchange, because this method is performed with a two-site technique using a peripheral artery and vein.

  16. The Na+/H+ exchanger NHE1 in stress-induced signal transduction: implications for cell proliferation and cell death

    DEFF Research Database (Denmark)

    Pedersen, Stine Falsig

    2006-01-01

    and acidification, include hypoxia and mechanical stimuli, such as cell stretch. It has recently become apparent that NHE1-mediated modulation of, e.g., cell migration, morphology, proliferation, and death results not only from NHE1-mediated changes in pHi, cell volume, and/or [Na+]i, but also from direct protein...... signaling event activated by stress conditions and modulating cell proliferation and death. The pathophysiological importance of NHE1 in modulating the balance between cell proliferation and cell death in cancer and in ischemia/severe hypoxia will also be briefly addressed.......The ubiquitous plasma membrane Na+/H+ exchanger NHE1 is highly conserved across vertebrate species and is extensively characterized as a major membrane transport mechanism in the regulation of cellular pH and volume. In recent years, the understanding of the role of NHE1 in regulating cell function...

  17. Proton exchange membrane fuel cells for electrical power generation on-board commercial airplanes.

    Energy Technology Data Exchange (ETDEWEB)

    Curgus, Dita Brigitte; Munoz-Ramos, Karina (Sandia National Laboratories, Albuquerque, NM); Pratt, Joseph William; Akhil, Abbas Ali (Sandia National Laboratories, Albuquerque, NM); Klebanoff, Leonard E.; Schenkman, Benjamin L. (Sandia National Laboratories, Albuquerque, NM)

    2011-05-01

    Deployed on a commercial airplane, proton exchange membrane fuel cells may offer emissions reductions, thermal efficiency gains, and enable locating the power near the point of use. This work seeks to understand whether on-board fuel cell systems are technically feasible, and, if so, if they offer a performance advantage for the airplane as a whole. Through hardware analysis and thermodynamic and electrical simulation, we found that while adding a fuel cell system using today's technology for the PEM fuel cell and hydrogen storage is technically feasible, it will not likely give the airplane a performance benefit. However, when we re-did the analysis using DOE-target technology for the PEM fuel cell and hydrogen storage, we found that the fuel cell system would provide a performance benefit to the airplane (i.e., it can save the airplane some fuel), depending on the way it is configured.

  18. Proton Exchange Membrane Fuel Cells for Electrical Power Generation On-Board Commercial Airplanes

    Energy Technology Data Exchange (ETDEWEB)

    Pratt, Joesph W. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Klebanoff, Leonard E. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Munoz-Ramos, Karina [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Akhil, Abbas A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Curgus, Dita B. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Schenkman, Benjamin L. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2011-05-01

    Deployed on a commercial airplane, proton exchange membrane fuel cells may offer emissions reductions, thermal efficiency gains, and enable locating the power near the point of use. This work seeks to understand whether on-board fuel cell systems are technically feasible, and, if so, if they offer a performance advantage for the airplane as a whole. Through hardware analysis and thermodynamic and electrical simulation, we found that while adding a fuel cell system using today’s technology for the PEM fuel cell and hydrogen storage is technically feasible, it will not likely give the airplane a performance benefit. However, when we re-did the analysis using DOE-target technology for the PEM fuel cell and hydrogen storage, we found that the fuel cell system would provide a performance benefit to the airplane (i.e., it can save the airplane some fuel), depending on the way it is configured.

  19. Characterization of anion exchange ionomers in hybrid polymer electrolyte fuel cells.

    Science.gov (United States)

    Unlü, Murat; Zhou, Junfeng; Anestis-Richard, Irene; Kohl, Paul A

    2010-12-17

    Anion exchange ionomers (AEI) synthesized here were characterized by use of a novel fuel cell configuration. The new analysis method involves assembling the AEI electrode of interest as the cathode in a hybrid, acid/alkaline, fuel cell configuration. The hybrid cell includes a conventional proton conducting anode/membrane half-cell along with the anionic conductor of interest at the cathode. Electrochemical impedance spectroscopy and voltammetry were used to evaluate the performance of the hybrid AEI-containing fuel cell with H₂ and O₂. In particular, the AEI electrode response in impedance spectroscopy was easily identified because the contributions from other components are largely minimized in the presented hybrid cell configuration. The properties of ionomers used in the AEI electrode were shown to have a substantial effect on the electrode performance. Low catalyst utilization, due to high water uptake and low conductivity, was identified as the major causes of poor performance in AEI electrodes.

  20. Filters in autologous blood retransfusion systems affect the amount of blood cells retransfused in total knee arthroplasty: a pilot study.

    Science.gov (United States)

    Moonen, Adrianus F C M; Pilot, Peter; Meijers, Wil G H; Waelen, Richard A J; Leers, Mathie P G; Grimm, Bernd; Heyligers, Ide C

    2008-04-01

    A pilot study was undertaken to evaluate whether filters integrated in postoperative retransfusion systems affect the amount of blood cells retransfused after total knee arthroplasty. Twenty-two consecutive patients received either the Donor retransfusion system (n=12 patients) or the Bellovac ABT retransfusion system (n=10). Both systems differ with respect to the type of filter, a Pall Lipiguard filter and a Sangopur filter, respectively. At the beginning of the retransfusion, blood samples were taken before and after the filter. The filter of the Donor system significantly decreased the amount of leukocytes and erythrocytes, whereas the filter of the Bellovac system did not. As a result the haemoglobin level of retransfused blood with the Donor system was significantly lower than with the Bellovac system. It can be concluded that the type of filter integrated in two postoperative autologous blood retransfusion systems significantly affected the amount of blood cells retransfused in patients undergoing total knee arthroplasty.

  1. Alkaline anion exchange membrane fuel cells for cogeneration of electricity and valuable chemicals

    Science.gov (United States)

    Pan, Z. F.; Chen, R.; An, L.; Li, Y. S.

    2017-10-01

    Alkaline anion exchange membrane fuel cells (AAEMFCs) have received ever-increasing attentions due to the enhanced electrochemical kinetics and the absence of precious metal electrocatalysts, and thus great progress has been made in recent years. The alkaline anion exchange membrane based direct alcohol fuel cells, one type of alkaline anion exchange membrane fuel cells utilizing liquid alcohols as fuel that can be obtained from renewable biomass feedstocks, is another attractive point due to its ability to provide electricity with cogeneration of valuable chemicals. Significant development has been made to improve the selectivity towards high added-value chemicals and power output in the past few years. This review article provides a general description of this emerging technology, including fuel-cell setup and potential reaction routes, summarizes the products, performance, and system designs, as well as introduces the application of this concept in the removal of heavy-metal ions from the industrial wastewater. In addition, the remaining challenges and perspectives are also highlighted.

  2. Mass and Heat Transfer in Ion-Exchange Membranes Applicable to Solid Polymer Fuel Cells

    Energy Technology Data Exchange (ETDEWEB)

    Otteroey, M.

    1996-04-01

    In this doctoral thesis, an improved emf method for determination of transference numbers of two counter ions in ion-exchange membranes is presented. Transference numbers were obtained as a continuous function of the composition. The method avoids problems with diffusion by using a stack of membranes. Water transference coefficients in ion-exchange membranes is discussed and reversible and irreversible water transfer is studied by emf methods. Efforts were made to get data relevant to the solid polymer fuel cell. The results support the findings of other researchers that the reversible water transfer is lower than earlier predicted. A chapter on the conductivity of ion-exchange membranes establishes a method to separate the very thin liquid layers surrounding the membranes in a stack. Using the method it was found that the conductivity is obtained with high accuracy and that the liquid layer in a membrane stack can contribute significantly to the total measured resistance. A four point impedance method was tested to measure the conductivity of membranes under fuel cell conditions. Finally, there is a discussion of reversible heat effects and heat transfer in ion-exchange membranes. 155 refs., 45 figs., 13 tabs.

  3. Clinical evaluation of a 51Cr-labeled red blood cell survival test for in vivo blood compatibility testing

    International Nuclear Information System (INIS)

    Pineda, A.A.; Dharkar, D.D.; Wahner, H.W.

    1984-01-01

    Modified red blood cell survival studies with use of 51Cr were performed in three groups of subjects. Group 1 consisted of normal subjects who were given labeled autologous blood, group 2 were subjects in need of blood transfusions and given labeled ABO and Rh crossmatch-compatible blood, and group 3 were patients in need of blood transfusion but in whom problems arose in finding compatible blood. The results of the studies suggest that for patients with blood compatibility problems, normal red blood cell survival values at 1 hour do not exclude the possibility of severe hemolysis 24 hours later. Thus, if a 1-hour test result is normal, the procedure should be extended routinely to 24 hours. Moreover, the test can be used to evaluate the clinical importance of antibodies. We showed that anti-Yka and anti-Lan were clinically significant, but high-titer, low-avidity antibodies, anti-Kna, anti-I, and anti-HI were clinically insignificant in the cases studied. This finding emphasizes the importance of an in vivo test for the final compatibility evaluation in complicated blood replacement problems

  4. Collection, processing and testing of bone, corneas, umbilical cord blood and haematopoietic stem cells by European Blood Alliance members

    DEFF Research Database (Denmark)

    Närhi, M; Natri, O; Desbois, I

    2013-01-01

    A questionnaire study was carried out in collaboration with the European Blood Alliance (EBA) Tissues and Cells (T&C) working group. The aim was to assess the level of involvement and commonality of processes on the procurement, testing and storage of bone, corneas, umbilical cord blood (UCB) and......) and haematopoietic stem cells (HSC) in order to identify different practices and to explore whether recommendations can be made for harmonization.......A questionnaire study was carried out in collaboration with the European Blood Alliance (EBA) Tissues and Cells (T&C) working group. The aim was to assess the level of involvement and commonality of processes on the procurement, testing and storage of bone, corneas, umbilical cord blood (UCB...

  5. Detection of tumor-associated cells in cryopreserved peripheral blood mononuclear cell samples for retrospective analysis.

    Science.gov (United States)

    Zhu, Peixuan; Stanton, Melissa L; Castle, Erik P; Joseph, Richard W; Adams, Daniel L; Li, Shuhong; Amstutz, Platte; Tang, Cha-Mei; Ho, Thai H

    2016-07-02

    Cryopreserved peripheral blood mononuclear cells (PBMCs) are commonly collected in biobanks. However, little data exist regarding the preservation of tumor-associated cells in cryopreserved collections. The objective of this study was to determine the feasibility of using the CellSieve™ microfiltration assay for the isolation of circulating tumor cells (CTCs) and circulating cancer-associated macrophage-like cells (CAMLs) from cryopreserved PBMC samples. Blood samples spiked with breast (MCF-7), prostate (PC-3), and renal (786-O) cancer cell lines were used to establish analytical accuracy, efficiency, and reproducibility after cryopreservation. The spiked samples were processed through Ficoll separation, and cryopreservation was followed by thawing and microfiltration. MCF-7 cells were successfully retrieved with recovery efficiencies of 90.5 % without cryopreservation and 87.8 and 89.0 %, respectively, on day 7 and day 66 following cryopreservation. The corresponding recovery efficiencies of PC-3 cells were 83.3 % without cryopreservation and 85.3 and 84.7 %, respectively, after cryopreservation. Recovery efficiencies of 786-O cells were 92.7 % without cryopreservation, and 82.7 and 81.3 %, respectively, after cryopreservation. The recovered cells retained the morphologic characteristics and immunohistochemical markers that had been observed before freezing. The protocols were further validated by quantitation of CAMLs in blood samples from two patients with renal cell carcinoma (RCC). The recovery rates of CTCs and CAMLs from cryopreserved samples were not statistically significant different (P > 0.05) from matched fresh samples. To our knowledge, this is the first report that CAMLs could be cryopreserved and analyzed after thawing with microfiltration technology. The application of microfiltration technology to cryopreserved samples will enable much greater retrospective study of cancer patients in relation to long-term outcomes.

  6. Multiple loci are associated with white blood cell phenotypes.

    Directory of Open Access Journals (Sweden)

    Michael A Nalls

    2011-06-01

    Full Text Available White blood cell (WBC count is a common clinical measure from complete blood count assays, and it varies widely among healthy individuals. Total WBC count and its constituent subtypes have been shown to be moderately heritable, with the heritability estimates varying across cell types. We studied 19,509 subjects from seven cohorts in a discovery analysis, and 11,823 subjects from ten cohorts for replication analyses, to determine genetic factors influencing variability within the normal hematological range for total WBC count and five WBC subtype measures. Cohort specific data was supplied by the CHARGE, HeamGen, and INGI consortia, as well as independent collaborative studies. We identified and replicated ten associations with total WBC count and five WBC subtypes at seven different genomic loci (total WBC count-6p21 in the HLA region, 17q21 near ORMDL3, and CSF3; neutrophil count-17q21; basophil count- 3p21 near RPN1 and C3orf27; lymphocyte count-6p21, 19p13 at EPS15L1; monocyte count-2q31 at ITGA4, 3q21, 8q24 an intergenic region, 9q31 near EDG2, including three previously reported associations and seven novel associations. To investigate functional relationships among variants contributing to variability in the six WBC traits, we utilized gene expression- and pathways-based analyses. We implemented gene-clustering algorithms to evaluate functional connectivity among implicated loci and showed functional relationships across cell types. Gene expression data from whole blood was utilized to show that significant biological consequences can be extracted from our genome-wide analyses, with effect estimates for significant loci from the meta-analyses being highly corellated with the proximal gene expression. In addition, collaborative efforts between the groups contributing to this study and related studies conducted by the COGENT and RIKEN groups allowed for the examination of effect homogeneity for genome-wide significant associations across

  7. Multiple Loci Are Associated with White Blood Cell Phenotypes

    Science.gov (United States)

    Yang, Qiong; Greinacher, Andreas; Wood, Andrew R.; Garcia, Melissa; Gasparini, Paolo; Liu, Yongmei; Lumley, Thomas; Folsom, Aaron R.; Reiner, Alex P.; Gieger, Christian; Lagou, Vasiliki; Felix, Janine F.; Völzke, Henry; Gouskova, Natalia A.; Biffi, Alessandro; Döring, Angela; Völker, Uwe; Chong, Sean; Wiggins, Kerri L.; Rendon, Augusto; Dehghan, Abbas; Moore, Matt; Taylor, Kent; Wilson, James G.; Lettre, Guillaume; Hofman, Albert; Bis, Joshua C.; Pirastu, Nicola; Fox, Caroline S.; Meisinger, Christa; Sambrook, Jennifer; Arepalli, Sampath; Nauck, Matthias; Prokisch, Holger; Stephens, Jonathan; Glazer, Nicole L.; Cupples, L. Adrienne; Okada, Yukinori; Takahashi, Atsushi; Kamatani, Yoichiro; Matsuda, Koichi; Tsunoda, Tatsuhiko; Tanaka, Toshihiro; Kubo, Michiaki; Nakamura, Yusuke; Yamamoto, Kazuhiko; Kamatani, Naoyuki; Stumvoll, Michael; Tönjes, Anke; Prokopenko, Inga; Illig, Thomas; Patel, Kushang V.; Garner, Stephen F.; Kuhnel, Brigitte; Mangino, Massimo; Oostra, Ben A.; Thein, Swee Lay; Coresh, Josef; Wichmann, H.-Erich; Menzel, Stephan; Lin, JingPing; Pistis, Giorgio; Uitterlinden, André G.; Spector, Tim D.; Teumer, Alexander; Eiriksdottir, Gudny; Gudnason, Vilmundur; Bandinelli, Stefania; Frayling, Timothy M.; Chakravarti, Aravinda; van Duijn, Cornelia M.; Melzer, David; Ouwehand, Willem H.; Levy, Daniel; Boerwinkle, Eric; Singleton, Andrew B.; Hernandez, Dena G.; Longo, Dan L.; Soranzo, Nicole; Witteman, Jacqueline C. M.; Psaty, Bruce M.; Ferrucci, Luigi; Harris, Tamara B.; O'Donnell, Christopher J.; Ganesh, Santhi K.

    2011-01-01

    White blood cell (WBC) count is a common clinical measure from complete blood count assays, and it varies widely among healthy individuals. Total WBC count and its constituent subtypes have been shown to be moderately heritable, with the heritability estimates varying across cell types. We studied 19,509 subjects from seven cohorts in a discovery analysis, and 11,823 subjects from ten cohorts for replication analyses, to determine genetic factors influencing variability within the normal hematological range for total WBC count and five WBC subtype measures. Cohort specific data was supplied by the CHARGE, HeamGen, and INGI consortia, as well as independent collaborative studies. We identified and replicated ten associations with total WBC count and five WBC subtypes at seven different genomic loci (total WBC count—6p21 in the HLA region, 17q21 near ORMDL3, and CSF3; neutrophil count—17q21; basophil count- 3p21 near RPN1 and C3orf27; lymphocyte count—6p21, 19p13 at EPS15L1; monocyte count—2q31 at ITGA4, 3q21, 8q24 an intergenic region, 9q31 near EDG2), including three previously reported associations and seven novel associations. To investigate functional relationships among variants contributing to variability in the six WBC traits, we utilized gene expression- and pathways-based analyses. We implemented gene-clustering algorithms to evaluate functional connectivity among implicated loci and showed functional relationships across cell types. Gene expression data from whole blood was utilized to show that significant biological consequences can be extracted from our genome-wide analyses, with effect estimates for significant loci from the meta-analyses being highly corellated with the proximal gene expression. In addition, collaborative efforts between the groups contributing to this study and related studies conducted by the COGENT and RIKEN groups allowed for the examination of effect homogeneity for genome-wide significant associations across populations

  8. Nanostructure-based proton exchange membrane for fuel cell applications at high temperature.

    Science.gov (United States)

    Li, Junsheng; Wang, Zhengbang; Li, Junrui; Pan, Mu; Tang, Haolin

    2014-02-01

    As a clean and highly efficient energy source, the proton exchange membrane fuel cell (PEMFC) has been considered an ideal alternative to traditional fossil energy sources. Great efforts have been devoted to realizing the commercialization of the PEMFC in the past decade. To eliminate some technical problems that are associated with the low-temperature operation (such as catalyst poisoning and poor water management), PEMFCs are usually operated at elevated temperatures (e.g., > 100 degrees C). However, traditional proton exchange membrane (PEM) shows poor performance at elevated temperature. To achieve a high-performance PEM for high temperature fuel cell applications, novel PEMs, which are based on nanostructures, have been developed recently. In this review, we discuss and summarize the methods for fabricating the nanostructure-based PEMs for PEMFC operated at elevated temperatures and the high temperature performance of these PEMs. We also give an outlook on the rational design and development of the nanostructure-based PEMs.

  9. IL-17A induces Pendrin expression and chloride-bicarbonate exchange in human bronchial epithelial cells.

    Directory of Open Access Journals (Sweden)

    Kelly M Adams

    Full Text Available The epithelium plays an active role in the response to inhaled pathogens in part by responding to signals from the immune system. Epithelial responses may include changes in chemokine expression, increased mucin production and antimicrobial peptide secretion, and changes in ion transport. We previously demonstrated that interleukin-17A (IL-17A, which is critical for lung host defense against extracellular bacteria, significantly raised airway surface pH in vitro, a finding that is common to a number of inflammatory diseases. Using microarray analysis of normal human bronchial epithelial (HBE cells treated with IL-17A, we identified the electroneutral chloride-bicarbonate exchanger Pendrin (SLC26A4 as a potential mediator of this effect. These data were verified by real-time, quantitative PCR that demonstrated a time-dependent increase in Pendrin mRNA expression in HBE cells treated with IL-17A up to 48 h. Using immunoblotting and immunofluorescence, we confirmed that Pendrin protein expression is increased in IL-17 treated HBE cells and that it is primarily localized to the mucosal surface of the cells. Functional studies using live-cell fluorescence to measure intracellular pH demonstrated that IL-17A induced chloride-bicarbonate exchange in HBE cells that was not present in the absence of IL-17A. Furthermore, HBE cells treated with short interfering RNA against Pendrin showed substantially reduced chloride-bicarbonate exchange. These data suggest that Pendrin is part of IL-17A-dependent epithelial changes and that Pendrin may therefore be a therapeutic target in IL-17A-dependent lung disease.

  10. Dynamics of indicators of a metabolic exchange and condition of blood circulation of the bottom extremities after traction extension at patients with lumbar and sacral dorsopathy

    Directory of Open Access Journals (Sweden)

    Kotenko К.V.

    2013-12-01

    Full Text Available Aim: to study influence of traction therapy in a pulse mode in a complex with electrotherapy on a condition of blood circulation of the bottom extremities and level of a metabolic exchange. Material and methods. There had been examined 120 patients with a lumbar and sacral dorsopathy aged from 22 to 69 years (middle age of 49,5 years with prescription of a disease from 1 to 5 years, among them men of 34,2%, women of 65,8%. Results. The analysis of effects of various medical methods on a condition of local blood circulation in the bottom extremities showed that the most expressed its compensation is noted at complex application of mechanical pulse traction influence and electrotherapy for patients with a dorsopathy of lumbar and sacral department of a backbone that is confirmed by restoration to normal values of all indicators rheovasogramm. Conclusion. High clinical results of application of the combined medical and rehabilitation complex are based on compensation of local blood circulation that is shown in elimination of deficiency of blood supply due to improvement of a tone of arterial vessels and elimination of venous stagnation, and also due to increase of linear speed of a blood-groove and development of collateral blood circulation. Application of electrical impulse and mechanical traction influences, more at their combination promotes fermentative activity of the systems responsible for a protein exchange that is important for prevention of degenerate and dystrophic process progressing.

  11. An artificial blood vessel implanted three-dimensional microsystem for modeling transvascular migration of tumor cells.

    Science.gov (United States)

    Wang, Xue-Ying; Pei, Ying; Xie, Min; Jin, Zi-He; Xiao, Ya-Shi; Wang, Yang; Zhang, Li-Na; Li, Yan; Huang, Wei-Hua

    2015-02-21

    Reproducing a tumor microenvironment consisting of blood vessels and tumor cells for modeling tumor invasion in vitro is particularly challenging. Here, we report an artificial blood vessel implanted 3D microfluidic system for reproducing transvascular migration of tumor cells. The transparent, porous and elastic artificial blood vessels are obtained by constructing polysaccharide cellulose-based microtubes using a chitosan sacrificial template, and possess excellent cytocompatibility, permeability, and mechanical characteristics. The artificial blood vessels are then fully implanted into the collagen matrix to reconstruct the 3D microsystem for modeling transvascular migration of tumor cells. Well-defined simulated vascular lumens were obtained by proliferation of the human umbilical vein endothelial cells (HUVECs) lining the artificial blood vessels, which enables us to reproduce structures and functions of blood vessels and replicate various hemodynamic parameters. Based on this model, the adhesion and transvascular migration of tumor cells across the artificial blood vessel have been well reproduced.

  12. The morphological classification of normal and abnormal red blood cell using Self Organizing Map

    Science.gov (United States)

    Rahmat, R. F.; Wulandari, F. S.; Faza, S.; Muchtar, M. A.; Siregar, I.

    2018-02-01

    Blood is an essential component of living creatures in the vascular space. For possible disease identification, it can be tested through a blood test, one of which can be seen from the form of red blood cells. The normal and abnormal morphology of the red blood cells of a patient is very helpful to doctors in detecting a disease. With the advancement of digital image processing technology can be used to identify normal and abnormal blood cells of a patient. This research used self-organizing map method to classify the normal and abnormal form of red blood cells in the digital image. The use of self-organizing map neural network method can be implemented to classify the normal and abnormal form of red blood cells in the input image with 93,78% accuracy testing.

  13. One year review of the blood cell separator programme.

    Science.gov (United States)

    Tan, Y O; Kueh, Y K; Suri, R; Oon, C J; Ng, H W; Goh, C N; Ong, Y W

    1981-07-01

    Using the Haemonetic Model 30 intermittent continuous flow centrifuge, 142 procedures, including 64 granulocytes and platelets, 68 platelet collection, 8 therapeutic leukapheresis and 2 plasmapheresis were performed. Granulocyte transfusions (mean collection 1.39 x 10(10) granulocytes) were given to 27 neutropenic patients for febrile episodes which were unresponsive to systemic antibiotics. Thirty-eight thrombocytopenic patients received a mean of 4.2 x 10(11) platelets per collection. Bleeding was controlled in most of the patients who received transfusion with a mean rise in platelet count of 30.6 x 10(9)/L. Therapeutic leukapheresis were performed on 3 patients with chronic leukaemias. A mean of 2.53 x 10(11) cells were collected per run with a mean fall of 58.2 x 10(9)/L in the patients' white blood cell count. Plasmapheresis was used to treat 1 patient with multiple myeloma. The authors' experience demonstrates that cell separator support is essential for patients with bone marrow depression and that the therapeutic leukapheresis is effective therapy for selected patients with chronic leukaemias. Plasmapheresis is effective in patients with hyperviscosity syndrome.

  14. WHITE BLOOD CELLS IN POLISH ATHLETES OF VARIOUS SPORTS DISCIPLINES

    Directory of Open Access Journals (Sweden)

    Joanna Orysiak

    2012-04-01

    Full Text Available The purpose of this study was to examine the diversity of white blood cell (WBC counts and their subsets (neutrophils, lymphocytes and monocytes among competitive athletes of different sports disciplines. The blood samples were collected from 608 healthy, medically examined athletes (181 females and 427 males aged 20.1 ± 5.1 years, who represented five sport disciplines: canoeing, judo, rowing, swimming and volleyball. All blood samples were taken from the antecubital vein in the morning, after overnight fasting, in a seated position. Haematological analyses were conducted using a haematology analyser (ADVIA 120, Siemens. Neutropenia (defined as neutrophil count <2.0 · 10[sup]9[/sup]·L[sup]-1[/sup] was found in athletes of both sexes in each discipline. There was no incident of lymphopenia (defined as a lymphocyte count <1.0 · 10[sup]9[/sup]·L[sup]-1[/sup]. Monocytopenia (defined as a monocyte count <0.2 · 10[sup]9[/sup]·L[sup]-1[/sup] was seen only in male athletes, except judo athletes. Differences in WBC and their subset counts were related to sport disciplines: in volleyball players WBC counts were significantly higher than in athletes of canoeing and rowing (in females; neutrophil counts were the lowest in swimming athletes; lymphocyte counts were lower in athletes of canoeing than in volleyball and swimming, but only in females; monocyte counts were lower in athletes of canoeing than swimming (in females and judo (in males. In women, counts of neutrophils were greater and counts of monocytes were smaller than in men. It seems that prevalence of neutropenia and monocytopenia and differences in WBC counts and their subsets among disciplines could be related to the adaptive response to physical exercise.

  15. Assessment of leucoreduction of sickle cell trait blood: quality of the filtered product

    Science.gov (United States)

    Amar, Karim Ould; Bourdonné, Olivier; Bruneau, Sylvie; Sellami, Fatiha; Richard, Pascale

    2014-01-01

    Background With the implementation of universal leucoreduction of blood components in several industrialised countries, the problems associated with leucocyte filtration of sickle cell trait blood have been reconsidered. In this study, we assessed the use of high performance filters for leucoreduction of packed red blood cells donated from subjects with sickle cell trait and evaluated the incidence and recurrence of altered red blood cell filterability. Materials and methods Twenty-one volunteer donors with HbAS were compared to 21 donors with HbAA selected at random. The main parameters analysed were residual white blood cell count and post-filtration haemolysis. Filtration times, flow, volume and haemoglobin loss of the packed red blood cells were also determined. Results In all, 33% of HbAS red blood cell units with slow flow and prolonged filtration time had high residual white blood cell counts. In 7.7% of cases, despite flow through the filter, the units were not leucoreduced properly. Haemoglobin and volume loss were significantly greater in the slow filtration group. Significant post-filtration haemolysis was present in half of the units with high residual white blood cell counts. Discussion Despite the development of new technology for filtration, the problem of filterability of blood from donors with sickle cell trait is not yet resolved. Altered filterability of blood from sickle cell trait donors cannot be predicted from the donors’ characteristics and recurrence of the problem is not observed between donations. Screening blood donors for sickle cell trait to ensure the safety and quality of blood products for transfusion does, therefore, remain a relevant issue. PMID:23149143

  16. Helium Ion Microscopy of proton exchange membrane fuel cell electrode structures

    OpenAIRE

    Chiriaev, Serguei; Dam Madsen, Nis; Rubahn, Horst-Günter; Andersen, Shuang Ma

    2017-01-01

    Characterization of composite materials with microscopy techniques is an essential route to understanding their properties and degradation mechanisms, though the observation with a suitable type of microscopy is not always possible. In this work, we present proton exchange membrane fuel cell electrode interface structure dependence on ionomer content, systematically studied by Helium Ion Microscopy (HIM). A special focus was on acquiring high resolution images of the electrode structure and a...

  17. Effects of blood products on inflammatory response in endothelial cells in vitro.

    Directory of Open Access Journals (Sweden)

    Martin Urner

    Full Text Available BACKGROUND: Transfusing blood products may induce inflammatory reactions within the vascular compartment potentially leading to a systemic inflammatory response. Experiments were designed to assess the inflammatory potential of different blood products in an endothelial cell-based in vitro model and to compare baseline levels of potentially activating substances in transfusion products. METHODS: The inflammatory response from pre-activated (endotoxin-stimulated and non-activated endothelial cells as well as neutrophil endothelial transmigration in response to packed red blood cells (PRBC, platelet concentrates (PC and fresh frozen plasma (FFP was determined. Baseline inflammatory mediator and lipid concentrations in blood products were evaluated. RESULTS: Following incubation with all blood products, an increased inflammatory mediator release from endothelial cells was observed. Platelet concentrates, and to a lesser extent also FFP, caused the most pronounced response, which was accentuated in already pre-stimulated endothelial cells. Inflammatory response of endothelial cells as well as blood product-induced migration of neutrophils through the endothelium was in good agreement with the lipid content of the according blood product. CONCLUSION: Within the group of different blood transfusion products both PC and FFP have a high inflammatory potential with regard to activation of endothelial cells. Inflammation upon blood product exposure is strongly accentuated when endothelial cells are pre-injured. High lipid contents in the respective blood products goes along with an accentuated inflammatory reaction from endothelial cells.

  18. Joint IA and SFBC Macrocells and Small-Cells Coexistence under Minor Information Exchange

    Directory of Open Access Journals (Sweden)

    Syed Saqlain Ali

    2016-01-01

    Full Text Available The deployment of small-cells within the boundaries of a macrocell is considered to be an effective solution to cope with the current trend of higher data rates and improved system capacity. In the current heterogeneous configuration with the mass deployment of small-cells, it is preferred that these two cell types will coexist over the same spectrum, because acquiring additional spectrum licenses for small-cells is difficult and expensive. However, the coexistence leads to cross-tier/intersystem interference. In this context, this contribution investigates interference alignment (IA methods in order to mitigate the interference of macrocell base station towards the small-cell user terminals. More specifically, we design a diversity-oriented interference alignment scheme with space-frequency block codes (SFBCs. The main motivation for joint interference alignment with SFBC is to allow the coexistence of two systems under minor intersystem information exchange. The small-cells just need to know what space-frequency block code is used by the macrocell system and no intersystem channels need to be exchanged, contrarily to other schemes recently proposed. Numerical results show that the proposed method achieves a performance close to the case where full cooperation between the tiers is allowed.

  19. Relationship of CD34+ cells infused and red blood cell transfusion requirements after autologous peripheral blood stem cell transplants: a novel method of analysis.

    Science.gov (United States)

    Dunlop, Lindsay C; Heller, Gillian Z

    2012-04-01

    CD34+ cells infused predicts myeloid and platelet engraftment at the time of autologous stem cell transplantation. An association between the number of CD34+ cells infused and erythroid engraftment has yet to be established. Red blood cells transfused after autologous transplantation were compared with the number of CD34+ cells infused. Myeloid engraftment was assessed to confirm that normal engraftment kinetics occurred. Logistic regression established that the logarithm of the number of CD34+ cells infused (p = 0.0498) and admission hemoglobin (Hb; p < 0.001) predicted the need for transfusion. In those patients who required transfusion, standard regression methods were not valid. A novel model demonstrated that the initial Hb (p < 0.001) and diagnosis (p = 0.047) were significant predictors of transfusion requirements in patients needing transfusion. However, the number of CD34+ cells infused did not predict transfusion requirements in this group (p = 0.226). As myeloid engraftment demonstrated kinetics that have been previously described, it can be inferred that erythroid engraftment was not atypical. The number of CD34+ cells infused predicted the need for transfusion, although it did not predict the number of RBCs transfused in those patients having transfusion during their admission for autologous stem cell transplant. © 2011 American Association of Blood Banks.

  20. In-situ Monitoring of Internal Local Temperature and Voltage of Proton Exchange Membrane Fuel Cells

    Science.gov (United States)

    Lee, Chi-Yuan; Fan, Wei-Yuan; Hsieh, Wei-Jung

    2010-01-01

    The distribution of temperature and voltage of a fuel cell are key factors that influence performance. Conventional sensors are normally large, and are also useful only for making external measurements of fuel cells. Centimeter-scale sensors for making invasive measurements are frequently unable to accurately measure the interior changes of a fuel cell. This work focuses mainly on fabricating flexible multi-functional microsensors (for temperature and voltage) to measure variations in the local temperature and voltage of proton exchange membrane fuel cells (PEMFC) that are based on micro-electro-mechanical systems (MEMS). The power density at 0.5 V without a sensor is 450 mW/cm2, and that with a sensor is 426 mW/cm2. Since the reaction area of a fuel cell with a sensor is approximately 12% smaller than that without a sensor, but the performance of the former is only 5% worse. PMID:22163556

  1. In-situ monitoring of internal local temperature and voltage of proton exchange membrane fuel cells.

    Science.gov (United States)

    Lee, Chi-Yuan; Fan, Wei-Yuan; Hsieh, Wei-Jung

    2010-01-01

    The distribution of temperature and voltage of a fuel cell are key factors that influence performance. Conventional sensors are normally large, and are also useful only for making external measurements of fuel cells. Centimeter-scale sensors for making invasive measurements are frequently unable to accurately measure the interior changes of a fuel cell. This work focuses mainly on fabricating flexible multi-functional microsensors (for temperature and voltage) to measure variations in the local temperature and voltage of proton exchange membrane fuel cells (PEMFC) that are based on micro-electro-mechanical systems (MEMS). The power density at 0.5 V without a sensor is 450 mW/cm(2), and that with a sensor is 426 mW/cm(2). Since the reaction area of a fuel cell with a sensor is approximately 12% smaller than that without a sensor, but the performance of the former is only 5% worse.

  2. In-situ Monitoring of Internal Local Temperature and Voltage of Proton Exchange Membrane Fuel Cells

    Directory of Open Access Journals (Sweden)

    Chi-Yuan Lee

    2010-06-01

    Full Text Available The distribution of temperature and voltage of a fuel cell are key factors that influence performance. Conventional sensors are normally large, and are also useful only for making external measurements of fuel cells. Centimeter-scale sensors for making invasive measurements are frequently unable to accurately measure the interior changes of a fuel cell. This work focuses mainly on fabricating flexible multi-functional microsensors (for temperature and voltage to measure variations in the local temperature and voltage of proton exchange membrane fuel cells (PEMFC that are based on micro-electro-mechanical systems (MEMS. The power density at 0.5 V without a sensor is 450 mW/cm2, and that with a sensor is 426 mW/cm2. Since the reaction area of a fuel cell with a sensor is approximately 12% smaller than that without a sensor, but the performance of the former is only 5% worse.

  3. Stretching of red blood cells at high strain rates

    Science.gov (United States)

    Mancuso, J. E.; Ristenpart, W. D.

    2017-10-01

    Most work on the mechanical behavior of red blood cells (RBCs) in flow 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 Rapid Communication, 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 both the Kelvin-Voigt and Skalak viscoelastic models capture the observed stretching dynamics, up to strain rates as high as 2000 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.

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

    DEFF Research Database (Denmark)

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

    2015-01-01

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

  5. Red blood cell sodium transport in patients with cirrhosis

    DEFF Research Database (Denmark)

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

    2016-01-01

    Patients with advanced cirrhosis have abnormal sodium homoeostasis. The study was undertaken to quantify the sodium transport across the plasma membrane of red blood cells (RBC) in patients with cirrhosis. RBC efflux and influx of sodium were studied in vitro with tracer (22) Na(+) according...... to linear kinetics in 24 patients with cirrhosis and 14 healthy controls. The sodium efflux was modified by ouabain (O), furosemide (F) and a combination of O and F (O + F). RBC sodium was significantly decreased (4·6 versus control 6·3 mmol l(-1) , Psodium (r = 0·57, P......sodium efflux was higher in patients with cirrhosis (+46%, Psodium buffers showed that the F-insensitive sodium efflux was twice as high in cirrhosis as in controls (P = 0...

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

    Science.gov (United States)

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

    2017-01-01

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

  7. The Antioxidant Effect of Erythropoietin on Thalassemic Blood Cells

    Directory of Open Access Journals (Sweden)

    Johnny Amer

    2010-01-01

    Full Text Available Because of its stimulating effect on RBC production, erythropoietin (Epo is used to treat anemia, for example, in patients on dialysis or on chemotherapy. In β-thalassemia, where Epo levels are low relative to the degree of anemia, Epo treatment improves the anemia state. Since RBC and platelets of these patients are under oxidative stress, which may be involved in anemia and thromboembolic complications, we investigated Epo as an antioxidant. Using flow-cytometry technology, we found that in vitro treatment with Epo of blood cells from these patients increased their glutathione content and reduced their reactive oxygen species, membrane lipid peroxides, and external phosphatidylserine. This resulted in reduced susceptibility of RBC to undergo hemolysis and phagocytosis. Injection of Epo into heterozygous (Hbbth3/+ β-thalassemic mice reduced the oxidative markers within 3 hours. Our results suggest that, in addition to stimulating RBC and fetal hemoglobin production, Epo might alleviate symptoms of hemolytic anemias as an antioxidant.

  8. Na(+)/H(+) exchange subtype 1 inhibition during extracellular acidification and hypoxia in glioma cells.

    Science.gov (United States)

    Glunde, Kristine; Düssmann, Heiko; Juretschke, Hans-Paul; Leibfritz, Dieter

    2002-01-01

    Lactacidosis is a common feature of ischaemic brain tissue, but its role in ischaemic neuropathology is still not fully understood. Na(+)/H(+) exchange, a mechanism involved in the regulation of intracellular pH (pH(i)), is activated by low pH(i). The role of Na(+)/H(+) exchange subtype 1 was investigated during extracellular acidification and subsequent pH recovery in the absence and presence of (4-isopropyl-3-methylsulphonyl-benzoyl)-guanidine methanesulfonate (HOE642, Cariporid), a new selective and powerful inhibitor of the Na(+)/H(+) exchanger subtype 1 (NHE-1). It was compared for normoxia and hypoxia in two glioma cell lines (C6 and F98). pH(i) was monitored by fluorescence spectroscopy using the intracellularly trapped pH-sensitive dye 2',7'-bis(carboxyethyl)-5(6)-carboxyfluorescein (BCECF). Alterations in glial cell metabolism were characterized using high-resolution (1)H, (13)C and (31)P NMR spectroscopy of perchloric acid extracts. NHE-1 contributed to glial pH regulation, especially at pathologically low pH(i) values. NHE-1 inhibition with HOE642 during acidification caused exacerbated metabolic disorders which were prolonged during extracellular pH recovery. However, NHE-1 inhibition during hypoxia protected the energy state of glial cells.

  9. Quantitative assessment of limb blood flow using Tc-99m labeled red blood cells. Radionuclide venous occlusion plethysmography (RAVOP)

    Energy Technology Data Exchange (ETDEWEB)

    Itoh, Kazuo; Shougase, Takashi; Kawamura, Naoyuki; Tsukamoto, Eriko; Nakada, Kunihiro; Sakuma, Makoto; Furudate, Masayori

    1987-10-01

    A quantitative assessment of limb blood flow using a non-diffusible radioindicator, Tc-99m labeled red blood cells, was reported. This was an application of venous occlusion plethysmography using radionuclide which was originally proposed by M. Fukuoka et al. The peripheral blood flow (mean +- s.e.) of 30 legs in a normal control group was 1.87 +- 0.08 ml/100 ml/min. In heart diseases (46 legs), it was 1.49 +- 0.13 ml/100 ml/min. The limb blood flow between a control group and heart diseases was statistically significant (p < 0.01) in the t-test. The peripheral blood flow at rest between diseased legs and normal legs in occlusive arterial disorders was also statistically significant (p < 0.01) in a paired t-test. RAVOP was done after the completion of objective studies such as radionuclide angiography or ventriculography. Technique and calculation of a blood flow were very easy and simple. RAVOP study which was originally proposed by Fukuoka et al. was reappraised to be hopeful for quantitative measurement of limb blood flow as a non-invasive technique using Tc-99m labeled red blood cells.

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

    Science.gov (United States)

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

    2015-10-01

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

  11. On the shape memory of red blood cells

    Science.gov (United States)

    Cordasco, Daniel; Bagchi, Prosenjit

    2017-04-01

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

  12. Characterization of Microvesicles Released from Human Red Blood Cells

    Directory of Open Access Journals (Sweden)

    Duc Bach Nguyen

    2016-03-01

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

  13. Plasticity of Cells and Ex Vivo Production of Red Blood Cells

    Directory of Open Access Journals (Sweden)

    Takashi Hiroyama

    2011-01-01

    Full Text Available The supply of transfusable red blood cells (RBCs is not sufficient in many countries. If transfusable RBCs could be produced abundantly from certain resources, it would be very useful. Our group has developed a method to produce enucleated RBCs efficiently from hematopoietic stem/progenitor cells present in umbilical cord blood. More recently, it was reported that enucleated RBCs could be abundantly produced from human embryonic stem (ES cells. The common obstacle for application of these methods is that they require very high cost to produce sufficient number of RBCs that are applicable in the clinic. If erythroid cell lines (immortalized cell lines able to produce transfusable RBCs ex vivo were established, they would be valuable resources. Our group developed a robust method to obtain immortalized erythroid cell lines able to produce mature RBCs. To the best of our knowledge, this was the first paper to show the feasibility of establishing immortalized erythroid progenitor cell lines able to produce enucleated RBCs ex vivo. This result strongly suggests that immortalized human erythroid progenitor cell lines able to produce mature RBCs ex vivo can also be established.

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

    Directory of Open Access Journals (Sweden)

    Chirico G

    2014-06-01

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

  15. Effects of ozone on isolated peripheral blood mononuclear cells.

    Science.gov (United States)

    Larini, A; Bocci, V

    2005-02-01

    We have investigated the release of cytokines from isolated peripheral human blood mononuclear cells (PBMC) exposed to various ozone concentrations for 10 min and the release of both proinflammatory and immunosuppressive cytokine after 24, 48 and 76 h incubation. Ozonation was performed by exposing for 10 min equal cell numbers and volumes of cell suspension to equal volumes of a gas mixture (1:1 ratio) composed of oxygen-ozone with precise ozone concentrations ranging from 1.0 up to 80 microg/ml (0.02 up to 1.68 mM). Markers of oxidative stress showed a significant relationship between ozone doses and both lipid peroxidation and protein thiol groups content. With the exception of the lowest ozone concentration, the cytokine production of PBMC was depressed particularly at concentrations from 40 mug/ml upwards. There was no significant effect on IL-6 production between exposed or unexposed cells, up to 72 h of incubation. IL-4 production was markedly affected by ozone exposure, showing a marked decrease even at the lowest ozone concentration (2.5 microg/ml) already after 24 h incubation. On the other hand, production of IFN-gamma and TNF-alpha was slightly stimulated by the lowest ozone dose either at all times or only after 72 h incubation, respectively. Analysis of the proliferation index (PI) is consistent with these results showing that, while the lowest concentration stimulates it, progressively increasing O(3) concentrations inhibit the PI. These data show that there is a significant relationship between cytokine production and ozone concentrations and that PBMC are very sensitive to oxidation particularly in presence of serum with low antioxidant capacity.

  16. Novel niobium carbide/carbon porous nanotube electrocatalyst supports for proton exchange membrane fuel cell cathodes

    Science.gov (United States)

    Nabil, Y.; Cavaliere, S.; Harkness, I. A.; Sharman, J. D. B.; Jones, D. J.; Rozière, J.

    2017-09-01

    Niobium carbide/carbon nanotubular porous structures have been prepared using electrospinning and used as electrocatalyst supports for proton exchange membrane fuel cells. They were functionalised with 3.1 nm Pt particles synthesised by a microwave-assisted polyol method and characterised for their electrochemical properties. The novel NbC-based electrocatalyst demonstrated electroactivity towards the oxygen reduction reaction as well as greater stability over high potential cycling than a commercial carbon-based electrocatalyst. Pt/NbC/C was integrated at the cathode of a membrane electrode assembly and characterised in a single fuel cell showing promising activity and power density.

  17. Durability Issues of High Temperature Proton Exchange Membrane Fuel Cells Based on Acid Doped Polybenzimidazole Membranes

    DEFF Research Database (Denmark)

    To achieve high temperature operation of proton exchange membrane fuel cells (PEMFC), preferably under ambient pressure, phosphoric acid doped polybenzimidazole (PBI) membrane represents an effective approach, which in recent years has motivated extensive research activities with great progress....... As a critical concern, issues of long term durability of PBI based fuel cells are addressed in this talk, including oxidative degradation of the polymer, mechanical failures of the membrane, acid leaching out, corrosion of carbon support and sintering of catalysts particles. Excellent polymer durability has...

  18. Continual Energy Management System of Proton Exchange Membrane Fuel Cell Hybrid Power Electric Vehicles

    Directory of Open Access Journals (Sweden)

    Ren Yuan

    2016-01-01

    Full Text Available Current research status in energy management of Proton Exchange Membrane (PEM fuel cell hybrid power electric vehicles are first described in this paper, and then build the PEMFC/ lithium-ion battery/ ultra-capacitor hybrid system model. The paper analysis the key factors of the continuous power available in PEM fuel cell hybrid power electric vehicle and hybrid power system working status under different driving modes. In the end this paper gives the working flow chart of the hybrid power system and concludes the three items of the system performance analysis.

  19. Electrocatalysts and their Supporting Materials for Proton Exchange Membrane Fuel Cells: Activity and Durability Studies

    DEFF Research Database (Denmark)

    Permyakova, Anastasia Aleksandrovna

    other methods. The thesis begins with an introduction in Chapter 1 providing an overview of fuel cells, their associated reaction mechanisms, catalysts and catalysts supports. Chapter 2 presents the theoretical background to the study including equipment and the techniques used to analyse the catalysts......This thesis describes investigations conducted exploring the activity, stability and durability of supported nano-particulate, bulk and thin film electrocatalysts used in proton exchange membrane fuel cells (PEMFCs). The effects of different factors and conditions on the reactions involved...

  20. Cord blood erythropoietin and cord blood nucleated red blood cells for prediction of adverse neonatal outcome associated with maternal obesity in term pregnancy: prospective cohort study.

    Science.gov (United States)

    Ibrahim, Mahmoud H; Moustafa, Asmaa N; Saedii, Ahmed A Fadil; Hassan, Ebtesam E

    2017-09-01

    To determine the adverse pregnancy outcomes associated with maternal pre-pregnancy overweight and obesity and we measure cord blood erythropoietin and NRBC count as indices of hypoxia and predictors of neonatal outcome. This prospective cohort study was done in Minia University Hospital, carried out from May 2015 to April 2016. Two hundred and seventy full-term neonates born to mothers of various body mass indices were included. Excluded were neonates with major factors known to be associated with a potential increase in fetal erythropoiesis. Pre-pregnancy maternal BMI was calculated from maternally reported weight and height. Cord blood erythropoietin and nucleated red blood cells were measured. There is a significant increase of various adverse pregnancy outcomes as cesarean section. Postpartum hemorrhage and macrosomia with the increase of maternal pre-pregnancy BMI. Significant positive correlations between cord blood erythropoietin and nucleated red blood cells with maternal BMI. The increase in the maternal pre-pregnancy BMI is associated with poor pregnancy outcomes. Cord blood erythropoietin and nucleated red blood cells can predict the poor neonatal outcome.

  1. Cross-stream distribution of red blood cells in sickle-cell disease

    Science.gov (United States)

    Zhang, Xiao; Lam, Wilbur; Graham, Michael

    2017-11-01

    Experiments revealed that in blood flow, red blood cells (RBCs) tend to migrate away from the vessel walls, leaving a cell-free layer near the walls, while leukocytes and platelets tend to marginate towards the vessel walls. This segregation behavior of different cellular components in blood flow can be driven by their differences in stiffness and shape. An alteration of this segregation behavior may explain endothelial dysfunction and pain crisis associated with sickle-cell disease (SCD). It is hypothesized that the sickle RBCs, which are considerably stiffer than the healthy RBCs, may marginate towards the vessel walls and exert repeated damage to the endothelial cells. Direct simulations are performed to study the flowing suspensions of deformable biconcave discoids and stiff sickles representing healthy and sickle cells, respectively. It is observed that the sickles exhibit a strong margination towards the walls. The biconcave discoids in flowing suspensions undergo a so-called tank-treading motion, while the sickles behave as rigid bodies and undergo a tumbling motion. The margination behavior and tumbling motion of the sickles may help substantiate the aforementioned hypothesis of the mechanism for the SCD complications and shed some light on the design of novel therapies.

  2. Blood shortage situation: An audit of red blood cells order and ...

    African Journals Online (AJOL)

    The objective of this work is to audit blood utilization by different specialties in the hospital using the Cross-match ratio as a guide to achieving effective transfusion practices. This was a prospective study. The blood bank of University Teaching Hospital in Benin City, Nigeria was used for the study. We analysed all blood ...

  3. Radionuclide assay of membrane Na+, K+-ATPase activity of peserved red blood cells

    International Nuclear Information System (INIS)

    Trusov, V.V.; Zelenin, A.A.; Marizin, S.A.

    1986-01-01

    The radionuclide tests were used to investigate the influence of varying blood preservatives on erythrocylic membrane Na + , K + -ATPase activity in samples of whole blood and packed red blood cells from normal donors prepared by standard methods. The tests were performed before and after seven days of preservation under standard conditions. It was found that blood preservations lowered membrane Na + , K + -ATPase activity: its minimum reduction was recorded with citroglucopnosphate, while glugicir induced a significant drop in Na + , K + -ATPase activity of preserved red blood cells regardless of the type of the blood transfusion solution. The assay of membrane Na + , K + -ATPase activity of preserved red blood cells with the use of 86 Rb could be recommended as an evaluation test for preserved blood and its components

  4. Differentiation potential of menstrual blood- versus bone marrow-stem cells into glial-like cells.

    Science.gov (United States)

    Azedi, Fereshteh; Kazemnejad, Somaieh; Zarnani, Amir Hassan; Behzadi, Gila; Vasei, Mohammad; Khanmohammadi, Manijeh; Khanjani, Sayeh; Edalatkhah, Haleh; Lakpour, Niknam

    2014-05-01

    Menstrual blood is easily accessible, renewable, and inexpensive source of stem cells that have been interested for cell therapy of neurodegenerative diseases. In this study, we showed conversion of menstrual blood stem cells (MenSCs) into clonogenic neurosphere- like cells (NSCs), which can be differentiated into glial-like cells. Moreover, differentiation potential of MenSCs into glial lineage was compared with bone marrow stem cells (BMSCs). Differentiation potential of individual converted NSCs derived from MenSCs or BMSCs into glial-like cells was investigated using immunofluorescence staining and real-time polymerase chain reaction.The fibroblastic morphology of both MenSCs and BMSCs was turned into NSCs shape during first step of differentiation. NSCs derived from both BMSCs and MenSCs expressed higher levels of Olig-2 and Nestin markers compared to undifferentiated cells. The expression levels of myelin basic protein (MBP) mRNA up regulated only in BMSCs-NSCs no in MenSCs-NSCs. However, outgrowth of individual NSCs derived from both MenSCs and BMSCs into glial-like cells led to significant up regulation of glial fibrillary acidic protein,Olig-2 and MBP at mRNA and protein level accompanied with down regulation of Nestin protein.This is the first study demonstrating that MenSCs can be converted to NSCs with differentiation ability into glial-like cells. Accumulative data show different expression pattern of glial markers in differentiated MenSCs compared to BMSCs. The comparable differentiation potential, more accessibility and no invasive technique for sample collection of MenSCs in comparison with BMSCs introduce MenSCs as an apt, consistent and safe alternative to BMSCs for cell therapy of neurodegenerative diseases. © 2014 International Federation for Cell Biology.

  5. Proton exchange membrane fuel cells for electrical power generation on-board commercial airplanes

    International Nuclear Information System (INIS)

    Pratt, Joseph W.; Klebanoff, Leonard E.; Munoz-Ramos, Karina; Akhil, Abbas A.; Curgus, Dita B.; Schenkman, Benjamin L.

    2013-01-01

    Highlights: ► We examine proton exchange membrane fuel cells on-board commercial airplanes. ► We model the added fuel cell system’s effect on overall airplane performance. ► It is feasible to implement an on-board fuel cell system with current technology. ► Systems that maximize waste heat recovery are the best performing. ► Current PEM and H 2 storage technology results in an airplane performance penalty. -- Abstract: Deployed on a commercial airplane, proton exchange membrane (PEM) fuel cells may offer emissions reductions, thermal efficiency gains, and enable locating the power near the point of use. This work seeks to understand whether on-board fuel cell systems are technically feasible, and, if so, if they could offer a performance advantage for the airplane when using today’s off-the-shelf technology. We also examine the effects of the fuel cell system on airplane performance with (1) different electrical loads, (2) different locations on the airplane, and (3) expected advances in fuel cell and hydrogen storage technologies. Through hardware analysis and thermodynamic simulation, we found that an additional fuel cell system on a commercial airplane is technically feasible using current technology. Although applied to a Boeing 787-type airplane, the method presented is applicable to other airframes as well. Recovery and on-board use of the heat and water that is generated by the fuel cell is an important method to increase the benefit of such a system. The best performance is achieved when the fuel cell is coupled to a load that utilizes the full output of the fuel cell for the entire flight. The effects of location are small and location may be better determined by other considerations such as safety and modularity. Although the PEM fuel cell generates power more efficiently than the gas turbine generators currently used, when considering the effect of the fuel cell system on the airplane’s overall performance we found that an overall

  6. Thermal analysis of cryoprotective solutions for red blood cells.

    Science.gov (United States)

    Iijima, T

    1998-05-01

    A differential scanning calorimeter was used to study the thermal behavior of glycerol-water solutions (binary system) and the more complex glycerol-based cryoprotective solutions that are used clinically in order to examine the cryoprotective role of glycerol in preserving frozen red blood cells. The melting and glass transition temperatures for the clinically used cryoprotective solutions were as expected, based on the nonequilibriumphase diagram for cryoprotective solutions incorporating isotonic phosphate-buffered saline. Two zones were identified in which solidification occurred without the formation of ice crystals: a glassy state that is crystallographically amorphous was found for glycerol concentrations between 40 and 55% in the binary system and between 45 and 60% in the complex system; a glassy state in the complete absence of ice was found at glycerol concentrations greater than 55% for the binary system or 60% for the complex system. In clinical practice, cryoprotectants are used at initial concentrations lower than those at which these two glassy states occur but there is an increase in the effective glycerol concentration inside and outside the cells as ice forms during the freezing process.

  7. Does Erythropoietin Regulate TRPC Channels in Red Blood Cells?

    Directory of Open Access Journals (Sweden)

    Jens Danielczok

    2017-03-01

    Full Text Available Background: Cation channels play an essential role in red blood cells (RBCs ion homeostasis. One set of ion channels are the transient receptor potential channels of canonical type (TRPC channels. The abundance of these channels in primary erythroblasts, erythroid cell lines and RBCs was associated with an increase in intracellular Ca2+ upon stimulation with Erythropoietin (Epo. In contrast two independent studies on Epo-treated patients revealed diminished basal Ca2+ concentration or reduced phosphatidylserine exposure to the outer membrane leaflet. Methods: To resolve the seemingly conflicting reports we challenged mature human and mouse RBCs of several genotypes with Epo and Prostaglandin E2 (PGE2 and recorded the intracellular Ca2+ content. Next Generation Sequencing was utilised to approach a molecular analysis of reticulocytes. Results/Conclusions: Our results allow concluding that Epo and PGE2 regulation of the Ca2+ homeostasis is distinctly different between murine and human RBCs and that changes in intracellular Ca2+ upon Epo treatment is a primary rather than a compensatory effect. In human RBCs, Epo itself has no effect on Ca2+ fluxes but inhibits the PGE2-induced Ca2+ entry. In murine mature RBCs functional evidence indicates TRPC4/C5 mediated Ca2+ entry activated by Epo whereas PGE2 leads to a TRPC independent Ca2+ entry.

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

    International Nuclear Information System (INIS)

    Rocha, G.S.; Pereira, M.O.; Benarroz, M.O.; Frydman, J.N.G.; Rocha, V.C.; Pereira, M.J.; Fonseca, A.S.; Medeiros, A.C.; Bernardo-Filho, M.

    2011-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2011-01-15

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

  10. A Comprehensive Fluid Dynamic-Diffusion Model of Blood Microcirculation with Focus on Sickle Cell Disease

    Science.gov (United States)

    Le Floch, Francois; Harris, Wesley L.

    2009-11-01

    A novel methodology has been developed to address sickle cell disease, based on highly descriptive mathematical models for blood flow in the capillaries. Our investigations focus on the coupling between oxygen delivery and red blood cell dynamics, which is crucial to understanding sickle cell crises and is unique to this blood disease. The main part of our work is an extensive study of blood dynamics through simulations of red cells deforming within the capillary vessels, and relies on the use of a large mathematical system of equations describing oxygen transfer, blood plasma dynamics and red cell membrane mechanics. This model is expected to lead to the development of new research strategies for sickle cell disease. Our simulation model could be used not only to assess current researched remedies, but also to spur innovative research initiatives, based on our study of the physical properties coupled in sickle cell disease.

  11. Dynamic monitoring of blood-brain barrier integrity using water exchange index (WEI) during mannitol and CO2 challenges in mouse brain.

    Science.gov (United States)

    Huang, Shuning; Farrar, Christian T; Dai, Guangping; Kwon, Seon Joo; Bogdanov, Alexei A; Rosen, Bruce R; Kim, Young R

    2013-04-01

    The integrity of the blood-brain barrier (BBB) is critical to normal brain function. Traditional techniques for the assessment of BBB disruption rely heavily on the spatiotemporal analysis of extravasating contrast agents. However, such methods based on the leakage of relatively large molecules are not suitable for the detection of subtle BBB impairment or for the performance of repeated measurements in a short time frame. Quantification of the water exchange rate constant (WER) across the BBB using strictly intravascular contrast agents could provide a much more sensitive method for the quantification of the BBB integrity. To estimate WER, we have recently devised a powerful new method using a water exchange index (WEI) biomarker and demonstrated BBB disruption in an acute stroke model. Here, we confirm that WEI is sensitive to even very subtle changes in the integrity of the BBB caused by: (i) systemic hypercapnia and (ii) low doses of a hyperosmolar solution. In addition, we have examined the sensitivity and accuracy of WEI as a biomarker of WER using computer simulation. In particular, the dependence of the WEI-WER relation on changes in vascular blood volume, T1 relaxation of cellular magnetization and transcytolemmal water exchange was explored. Simulated WEI was found to vary linearly with WER for typically encountered exchange rate constants (1-4 Hz), regardless of the blood volume. However, for very high WER (>5 Hz), WEI became progressively more insensitive to increasing WER. The incorporation of transcytolemmal water exchange, using a three-compartment tissue model, helped to extend the linear WEI regime to slightly higher WER, but had no significant effect for most physiologically important WERs (WER < 4 Hz). Variation in cellular T1 had no effect on WEI. Using both theoretical and experimental approaches, our study validates the utility of the WEI biomarker for the monitoring of BBB integrity. Copyright © 2012 John Wiley & Sons, Ltd.

  12. Different cell moieties and white blood cell (WBC) integrity in In-111 labeled WBC preparations

    International Nuclear Information System (INIS)

    Saha, G.B.; Feiglin, D.H.I.; McMahon, J.T.; Go, R.T.; O'Donnell, J.K.; MacIntyre, W.J.

    1985-01-01

    Indium-111 labeled white blood cells (WBC) have become very popular in detecting inflammatory diseases. The purpose of this paper is to determine the distribution of different types of cells in WBC preparation for In-111 oxine labeling, and also to assess the histological integrity of WBC's after labeling with In-111 oxine. Forty to fifty cc of blood was collected from each patient and WBC's were separated by sedimentation and centrifugation. After labeling with In-111 oxine, an aliquot of the WBC sample was used for cell counting and a second aliquot was used for electron microscopic (EM) examination. The different cell moieties were counted, and the mean and standard deviation of twelve determinations calculated. Cells were prepared by the standard technique for electron microscopic examination and images of the cells were obtained at different magnifications (X8,000-25,000). The EM images revealed that although minimal cytoplasmic vacuolization occurred in the WBC's due to the labeling process, the overall histological integrity of the cells remained intact. The relative labeling efficiency of WBC's is greater than those of RBC's and platelets (J Nuc) Med 25:p98, 1984) and, therefore, even a comparatively low population of WBC's gives optimal imaging due to their increased tracer uptake

  13. Modulation of B-cell receptor and microenvironment signaling by a guanine exchange factor in B-cell malignancies

    International Nuclear Information System (INIS)

    Liao, Wei; Sharma, Sanjai

    2016-01-01

    Objective: Chronic lymphocytic leukemia (CLL) and mantle cell lymphoma (MCL) cells over-express a guanine exchange factor (GEF), Rasgrf-1. This GEF increases active Ras as it catalyzes the removal of GDP from Ras so that GTP can bind and activate Ras. This study aims to study the mechanism of action of Rasgrf-1 in B-cell malignancies. Methods: N-terminus truncated Rasgrf-1 variants have a higher GEF activity as compared to the full-length transcript therefore a MCL cell line with stable over-expression of truncated Rasgrf-1 was established. The B-cell receptor (BCR) and chemokine signaling pathways were compared in the Rasgrf-1 over-expressing and a control transfected cell line. Results: Cells over-expressing truncated form of Rasgrf-1 have a higher proliferative rate as compared to control transfected cells. BCR was activated by lower concentrations of anti-IgM antibody in Rasgrf-1 over-expressing cells as compared to control cells indicating that these cells are more sensitive to BCR signaling. BCR signaling also phosphorylates Rasgrf-1 that further increases its GEF function and amplifies BCR signaling. This activation of Rasgrf-1 in over-expressing cells resulted in a higher expression of phospho-ERK, AKT, BTK and PKC-alpha as compared to control cells. Besides BCR, Rasgrf-1 over-expressing cells were also more sensitive to microenvironment stimuli as determined by resistance to apoptosis, chemotaxis and ERK pathway activation. Conclusions: This GEF protein sensitizes B-cells to BCR and chemokine mediated signaling and also upregulates a number of other signaling pathways which promotes growth and survival of these cells

  14. The effect of increased centrifugation temperature on the quality of red-blood-cell concentrates of automated whole blood processing.

    Science.gov (United States)

    Weinigel, C; Rummler, S; Barz, D

    2013-10-01

    There are manual and automated methods to separate whole blood (WB) available. The Atreus whole blood processing system is an automated method, which combines centrifugation and expression of components into a single device. A major difference to conventional methods is that centrifugation temperature is not controlled at 22°C. The aim of this study was to examine the influence of increased centrifugation temperatures on the quality of red-blood-cell concentrates (RCC) after active cooling of WB prior to processing. A total of 28 WB were processed: 16 at centrifugation temperatures of up to 28°C (1st protocol) and 12 at 34°C (2nd protocol). RCC quality parameters were tested weekly for 42 days. Red-blood-cell concentrates (RCC) quality complied with the European and German guidelines. Haemolysis was not significantly different throughout storage. Significant statistical differences were detected between both protocols in potassium concentration at the end of storage and in ATP levels at the day of processing. Centrifugation temperatures of up to 34°C are well tolerated by the red blood cells with minimal interference with the RCC quality parameters. © 2013 International Society of Blood Transfusion.

  15. Quantitative Analysis of Human Red Blood Cell Proteome.

    Science.gov (United States)

    Bryk, Agata H; Wiśniewski, Jacek R

    2017-08-04

    Red blood cells (RBCs) are the most abundant cell type in the human body. RBCs and, in particular, their plasma membrane composition have been extensively studied for many years. During the past decade proteomics studies have extended our knowledge on RBC composition; however, these studies did not provide quantitative insights. Here we report a large-scale proteomics investigation of RBCs and their "white ghost" membrane fraction. Samples were processed using the multienzyme digestion filter-aided sample preparation (MED-FASP) and analyzed using Q-Exactive mass spectrometer. Protein abundances were computed using the total protein approach (TPA). The validation of the data with stable isotope-labeled peptide-based protein quantification followed. Our in-depth analysis resulted in the identification of 2650 proteins, of which 1890 occurred at more than 100 copies per cell. We quantified 41 membrane transporter proteins spanning an abundance range of five orders of magnitude. Some of these, including the drug transporter ABCA7 and choline transporters SLC44A1 and SLC44A2, have not previously been identified in RBC membranes. Comparison of protein copy numbers assessed by proteomics showed a good correlation with literature data; however, abundances of several proteins were not consistent with the classical references. Because we validated our findings by a targeted analysis using labeled standards, our data suggest that some older reference data from a variety of biochemical approaches are inaccurate. Our study provides the first "in-depth" quantitative analysis of the RBC proteome and will promote future studies of erythrocyte structure, functions, and disease.

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

    Science.gov (United States)

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

    2016-05-06

    This study investigated the effect of the biochemical and biophysical properties of the plasma membrane as well as membrane morphology on the susceptibility of human red blood cells to the cholesterol-dependent cytolysin pneumolysin, a key virulence factor of Streptococcus pneumoniae, using single cell studies. We show a correlation between the physical properties of the membrane (bending rigidity and surface and dipole electrostatic potentials) and the susceptibility of red blood cells to pneumolysin-induced hemolysis. We demonstrate that biochemical modifications of the membrane induced by oxidative stress, lipid scrambling, and artificial cell aging modulate the cell response to the toxin. We provide evidence that the diversity of response to pneumolysin in diabetic red blood cells correlates with levels of glycated hemoglobin and that the mechanical properties of the red blood cell plasma membrane are altered in diabetes. Finally, we show that diabetic red blood cells are more resistant to pneumolysin and the related toxin perfringolysin O relative to healthy red blood cells. Taken together, these studies indicate that the diversity of cell response to pneumolysin within a population of human red blood cells is influenced by the biophysical and biochemical status of the plasma membrane and the chemical and/or oxidative stress pre-history of the cell. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  17. Relative deformability of red blood cells in sickle cell trait and sickle cell anemia by trapping and dragging

    Science.gov (United States)

    Solomon, Rance; Cooper, James; Welker, Gabriel; Aguilar, Elaura; Flanagan, Brooke; Pennycuff, Chelsey; Scott, David; Farone, Anthony; Farone, Mary; Erenso, Daniel; Mushi, Robert; del Pilar Aguinaga, Maria

    2013-06-01

    Genetic mutation of the β-globin gene or inheritance of this mutated gene changes the chemical composition of the oxygen-carrying hemoglobin molecule that could lead to either the heterozygote genotype, resulting in sickle cell trait (SCT), or the homozygote genotype, resulting in sickle cell anemia (SCA). These mutations could affect the reversible elastic deformations of the red blood cells (RBCs) which are vital for biological functions. We have investigated this effect by studying the differences in the deformability of RBCs from blood samples of an individual with SCT and an untreated patient with SCA along with hemoglobin quantitation of each blood sample. Infrared 1064 nm laser trap force along with drag shear force are used to induce deformation in the RBCs. Ultra2-High Performance Liquid Chromatography (UHPLC) is used for the hemoglobin quantitation.

  18. Extending the Refrigerated Storage of Red Blood Cells

    National Research Council Canada - National Science Library

    Bitensky, Mark

    2004-01-01

    Oxygen removal increases shelf-life and quality of refrigerated blood. The shelf life of our blood has been prolonged to a minimum of 12 weeks with survival equal to or greater than that of conventional 6 week storage...

  19. Action of the poison of Apis mellifera bee and gamma radiation on bone marrow cells of Wistar rats and on lymphocytes of human peripheral blood

    International Nuclear Information System (INIS)

    Varanda, E.A.

    1987-01-01

    ''In vivo'' and ''in vitro'' experiments are performed to determine the radioprotective action of the poison of Apis mellifera bees. The frequency of chromosome aberrations, induced by gamma radiation, is studied in two assays: ''in vivo'' in bone marrow cells from Wistar rats and ''in vitro'' in human peripheral blood lymphocyte cultures. The sister chromatid exchanges (SCE) are studied in the ''in vitro'' assays. (M.A.C.) [pt

  20. Scientific problems in the regulation of red blood cell products.

    Science.gov (United States)

    Hess, John R

    2012-08-01

    For the past 30 years, red blood cell (RBC) storage systems have been licensed in the United States based on the demonstration that 24-hour in vivo recovery was greater than 75% and hemolysis was less than 1%. Now additional requirements for storage system licensure have being added. The meaning and value of these new requirements have been questioned. The literature regarding the performance of present and suggested new tests for RBC licensure was reviewed. (51) Cr 24-hr in vivo recovery has an intrinsic 4% error of measurement whereas the error in measures of hemolysis is less than 0.1%. Both measures have large donor-dependent end-of-storage variability; nevertheless, they have successfully guided RBC storage system development for six decades. Adenosine 5'-triphosphate and 2,3-diphosphoglycerate are difficult to measure accurately and international shared-sample studies suggest 6 and 11% coefficients of variation across laboratories. There is no readily available way to measure the oxygen equilibrium curve accurately. The new failure criteria provide no useful information and randomly fail good products. Attempts to expand the useful regulatory requirements for RBC storage system licensure are limited by poor understanding of the storage lesion and its effect of RBC performance. Measures of (51) Cr 24-hour in vivo recovery remain critical and resources for this measure are limiting. The interaction between limited testing resources and large donor variability remains a major limit on RBC storage system development. It is important that new required tests contribute meaningful information and not make development and licensure of better products more difficult. © 2012 American Association of Blood Banks.