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Sample records for blood cell aggregation

  1. 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.

  2. 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.

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

    Science.gov (United States)

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

    2015-06-01

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

  4. 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

  5. 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

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

    Directory of Open Access Journals (Sweden)

    Cardoso A.V.

    2002-01-01

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

  7. Light scattering method to measure red blood cell aggregation during incubation

    Science.gov (United States)

    Grzegorzewski, B.; Szołna-Chodór, A.; Baryła, J.; DreŻek, D.

    2018-01-01

    Red blood cell (RBC) aggregation can be observed both in vivo as well as in vitro. This process is a cause of alterations of blood flow in microvascular network. Enhanced RBC aggregation makes oxygen and nutrients delivery difficult. Measurements of RBC aggregation usually give a description of the process for a sample where the state of a solution and cells is well-defined and the system reached an equilibrium. Incubation of RBCs in various solutions is frequently used to study the effects of the solutions on the RBC aggregation. The aggregation parameters are compared before and after incubation while the detailed changes of the parameters during incubation remain unknown. In this paper we have proposed a method to measure red blood cell aggregation during incubation based on the well-known technique where backscattered light is used to assess the parameters of the RBC aggregation. Couette system consisting of two cylinders is adopted in the method. The incubation is observed in the Couette system. In the proposed method following sequence of rotations is adapted. Two minutes rotation is followed by two minutes stop. In this way we have obtained a time series of back scattered intensity consisting of signals respective for disaggregation and aggregation. It is shown that the temporal changes of the intensity manifest changes of RBC aggregation during incubation. To show the ability of the method to assess the effect of incubation time on RBC aggregation the results are shown for solutions that cause an increase of RBC aggregation as well as for the case where the aggregation is decreased.

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

    NARCIS (Netherlands)

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

    2009-01-01

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

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

    NARCIS (Netherlands)

    Baskurt, Oguz K.; Uyuklu, Mehmet; Hardeman, Max R.; Meiselman, Herbert J.

    2009-01-01

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

  10. Measurement of the temperature-dependent threshold shear-stress of red blood cell aggregation.

    Science.gov (United States)

    Lim, Hyun-Jung; Nam, Jeong-Hun; Lee, Yong-Jin; Shin, Sehyun

    2009-09-01

    Red blood cell (RBC) aggregation is becoming an important hemorheological parameter, which typically exhibits temperature dependence. Quite recently, a critical shear-stress was proposed as a new dimensional index to represent the aggregative and disaggregative behaviors of RBCs. The present study investigated the effect of the temperature on the critical shear-stress that is required to keep RBC aggregates dispersed. The critical shear-stress was measured at various temperatures (4, 10, 20, 30, and 37 degrees C) through the use of a transient microfluidic aggregometry. The critical shear-stress significantly increased as the blood temperature lowered, which accorded with the increase in the low-shear blood viscosity with the lowering of the temperature. Furthermore, the critical shear-stress also showed good agreement with the threshold shear-stress, as measured in a rotational Couette flow. These findings assist in rheologically validating the critical shear-stress, as defined in the microfluidic aggregometry.

  11. Normal and system lupus erythematosus red blood cell interactions studied by double trap optical tweezers: direct measurements of aggregation forces

    Science.gov (United States)

    Khokhlova, Maria D.; Lyubin, Eugeny V.; Zhdanov, Alexander G.; Rykova, Sophia Yu.; Sokolova, Irina A.; Fedyanin, Andrey A.

    2012-02-01

    Direct measurements of aggregation forces in piconewton range between two red blood cells in pair rouleau are performed under physiological conditions using double trap optical tweezers. Aggregation and disaggregation properties of healthy and pathologic (system lupus erythematosis) blood samples are analyzed. Strong difference in aggregation speed and behavior is revealed using the offered method which is proposed to be a promising tool for SLE monitoring at single cell level.

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

    Directory of Open Access Journals (Sweden)

    Kizzy-Clara Cita

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

  13. Effect of ionic and non-ionic contrast media on aggregation of red blood cells in vitro

    International Nuclear Information System (INIS)

    Raininko, R.; Ylinen, S.L.

    1987-01-01

    Fresh human blood without additives, and contrast medium were mixed and examined immediately by light microscopy in a non-flowing state. Sodium meglumine diatrizoate, meglumine diatrizoate, meglumine iodamide, sodium meglumine ioxaglate, iopromide, iopamidol, iohexol, and metrizamide were tested in concentrations of 300 mgI/ml. Physiologic saline and 5% glucose were used as controls. All media were tested in a randomized order with blood samples from 23 volunteers. No aggregation was detected in physiologic saline, and few rouleaux were found in ionic contrast media. Irregular red cell aggregates were found in all low-osmolal contrast media: in 17% of the specimens in ioxaglate, in 52% in metrizamide, and in 78 to 100% in other non-ionic media. Irregular aggregates were seen in all specimens with glucose. It remains to be domonstrated whether or not the irregular aggregation of human red cells in non-ionic contrast media has clinical significance. Iohexol was also tested with blood samples from several laboratory animals, but in nearly every case no aggregates were found. Results of animal experiments or tests with animal blood seem to be poorly applicable to man. (orig.)

  14. Improved viscosity modeling in patients with type 2 diabetes mellitus by accounting for enhanced red blood cell aggregation tendency

    NARCIS (Netherlands)

    Mutsaerts, Henri J. M. M.; Out, Mattijs; Goedhart, Peter T.; Ince, Can; Hardeman, Max R.; Romijn, Johannes A.; Rabelink, Ton J.; Reiber, Johan H. C.; Box, Frieke M. A.

    2010-01-01

    Aims: Distorted wall shear stress (WSS) in patients with type 2 diabetes mellitus (T2DM) may be partly explained by an altered red blood cell aggregation tendency (RAT) on viscosity at low shear rate (SR). The present study evaluates viscosity modeling by implementation of hematocrit and RAT in

  15. Inhibition of Platelet Aggregation by Supernates from Stored Red Blood Cells

    Science.gov (United States)

    2010-04-01

    450 μl of blood or 450 μl of platelet rich plasma (PRP) was mixed with 225 μl of supernate plus 225 μl of Tyrode’s buffer and incubated for ten... platelet counts, prothrombin time, activated partial thromboplastin time, fibrinogen, fibrin split products, and FVIII:Rag also measured 30 minutes...RTO-MP-HFM-182 22 - 1 Inhibition of Platelet Aggregation by Supernates from Stored Red Blood Cells Dr. Steve J. McFaul, LT Frederick A

  16. Effects of nattokinase, a pro-fibrinolytic enzyme, on red blood cell aggregation and whole blood viscosity.

    Science.gov (United States)

    Pais, Eszter; Alexy, Tamas; Holsworth, Ralph E; Meiselman, Herbert J

    2006-01-01

    The vegetable cheese-like food, natto, is extremely popular in Japan with a history extending back over 1000 years. A fibrinolytic enzyme, termed nattokinase, can be extracted from natto; the enzyme is a subtilisin-like serine protease composed of 275 amino acid residues and has a molecular weight of 27.7 kDa. In vitro and in vivo studies have consistently demonstrated the potent pro-fibrinolytic effect of the enzyme. However, no studies to date have evaluated the effects of nattokinase on various hemorheological parameters and thus we have begun to assess the effects of the enzyme on RBC aggregation and blood viscosity. Blood samples were incubated with nattokinase (final activities of 0, 15.6, 31.3, 62.5 and 125 units/ml) for 30 minutes at 37 degrees C. RBC aggregation was measured using a Myrenne MA-1 aggregometer and blood viscosity assessed over 1-1000 s(-1) with a computer controlled scanning capillary rheometer (Rheolog). Our in vitro results showed a significant, dose-dependent decrease of RBC aggregation and low-shear viscosity, with these beneficial effects evident at concentrations similar to those achieved in previous in vivo animal trials. Our preliminary data thus indicate positive in vitro hemorheological effects of nattokinase, and suggest its potential value as a therapeutic agent and the need for additional studies and clinical trials.

  17. Influence of mechanical cell salvage on red blood cell aggregation, deformability, and 2,3-diphosphoglycerate in patients undergoing cardiac surgery with cardiopulmonary bypass.

    Science.gov (United States)

    Gu, Y John; Vermeijden, Wytze J; de Vries, Adrianus J; Hagenaars, J Ans M; Graaff, Reindert; van Oeveren, Willem

    2008-11-01

    Mechanical cell salvage is increasingly used during cardiac surgery. Although this procedure is considered safe, it is unknown whether it affects the red blood cell (RBC) function, especially the RBC aggregation, deformability, and the contents of 2,3-diphosphoglycerate (2,3-DPG). This study examines the following: (1) whether the cell salvage procedure influences RBC function; and (2) whether retransfusion of the salvaged blood affects RBC function in patients. Forty patients undergoing cardiac surgery with cardiopulmonary bypass were randomly allocated to a cell saver group (n = 20) or a control group (n = 20). In the cell saver group, the blood aspirated from the wound area and the residual blood from the heart-lung machine were processed with a continuous-flow cell saver before retransfusion. In the control group this blood was retransfused without processing. The RBC aggregation and deformability were measured with a laser-assisted optical rotational cell analyzer and 2,3,-DPG by conventional laboratory test. The cell saver procedure did not influence the RBC aggregation but significantly reduced the RBC deformability (p = 0.007) and the content of RBC 2,3-DPG (p = 0.032). However, in patients receiving the processed blood, their intraoperative and postoperative RBC aggregation, deformability, and 2,3-DPG content did not differ from those of the control patients. Both groups of patients had a postoperative drop of RBC function as a result of hemodilution. The mechanical cell salvage procedure reduces the RBC deformability and the cell 2,3-DPG content. Retransfusion of the processed blood by cell saver does not further compromise the RBC function in patients undergoing cardiac surgery with cardiopulmonary bypass.

  18. Study of the influence of ultraviolet radiation on aggregative properties of blood red cell by light backscattering

    International Nuclear Information System (INIS)

    Azhnaj, L.; Chueltehm, D.

    1988-01-01

    The method based on the fact of measurable intensity of backscattered laser beam resulting from the angular distribution of scattered light is investigated. The method permits study of the mechanisms of aggregation and disaggregation processes by ultraviolet radiation and action of some inductors. The ultraviolet light acting directly on erythrocyte rouleaus of 10 x 100 μ causes the scattering of laser beam of wavelength 632,8 nm. According the above mentioned fact at an agle of approximately 180 0 the light intensity is measured. Stabilized blood sample is exposed to laser beam by means of fiber optics. Backscattering light transmitted through the photomultiplier and direct current supply is recorded. Quantitative concept of erythrocyte aggregation process is calculated from the plot. Blood sample is mixed by magnetic mixer and the measuring temperature is kept constantly at 37 0 C. Accordingly, the present model can adequately reproduce complex blood red cells kinetics. The influence of ultraviolet radiation and different kinds of inductors on erythrocytes' aggregation is experimentally studied depending on time. 2 figs. (B.Sh.)

  19. Red blood cell aggregation changes are depended on its initial value: Effect of long-term drug treatment and short-term cell incubation with drug.

    Science.gov (United States)

    Muravyov, A V; Tikhomirova, I A; Maimistova, A A; Bulaeva, S V; Mikhailov, P V; Kislov, N V

    2011-01-01

    This study was designed to investigate whether the red cell aggregation depends on its initial level under drug therapy or cell incubation with bioactive chemical compounds. Sixty six subjects were enrolled onto this study, and sub-divided into two groups: the first group of patients (n = 36) with cerebral atherosclerosis received pentoxifylline therapy (400 mg, thrice daily) for 4 weeks. The patients of the second group were initially treated with Epoetin beta 10,000 units subcutaneously thrice a week, for 4 weeks. The second group - adult anemic patients (n = 30) with the confirmed diagnosis of solid cancer (Hb treatment the red cell aggregation increased (p treatment with pentoxifylline reduced it markedly (p treatment 75% the anemic patients with initially high RBCA had an aggregation lowering. The drop of aggregation was about 34% (p treatment. The initially low red cell aggregation after incubation with epoetin-beta was markedly increased by 122% (p drugs depend markedly on the initial, pre-treatment aggregation status of the patients. These results demonstrate that the different red blood cell aggregation responses to the biological stimuli depend strongly on the initial, pre-treatment status of the subject and the most probably it is connected with the crosstalk between the adenylyl cyclase signaling pathway and Ca2+ regulatory mechanism.

  20. Secretome of Aggregated Embryonic Stem Cell-Derived Mesenchymal Stem Cell Modulates the Release of Inflammatory Factors in Lipopolysaccharide-Induced Peripheral Blood Mononuclear Cells

    Science.gov (United States)

    Mohammadi Ghahhari, Nastaran; Maghsood, Faezeh; Jahandideh, Saeed; Lotfinia, Majid; Lak, Shirin; Johari, Behrooz; Azarnezhad, Asaad; Kadivar, Mehdi

    2018-07-01

    Bone marrow mesenchymal stem cells (BM-MSCs) have emerged as a potential therapy for various inflammatory diseases. Because of some limitations, several recent studies have suggested the use of embryonic stem cell-derived MSCs (ESC-MSCs) as an alternative for BM-MSCs. Some of the therapeutic effects of the ESC-MSCs are related to the secretion of a broad array of cytokines and growth factors, known as secretome. Harnessing this secretome for therapeutic applications requires the optimization of production of secretary molecules. It has been shown that aggregation of MSCs into 3D spheroids, as a preconditioning strategy, can enhance immunomodulatory potential of such cells. In this study, we investigated the effect of secretome derived from human ESC-MSCs (hESC-MSCs) spheroids on secretion of IL-1β, IL-10, and tumor necrosis factor α (TNF-α) from lipopolysaccharide (LPS)-induced peripheral blood mononuclear cells (PBMCs). In the present study, after immunophenotyping and considering mesodermal differentiation of hESC-MSCs, the cells were non-adherently grown to prepare 3D aggregates, and then conditioned medium or secretome was extracted from the cultures. Afterwards, the anti-inflammatory effects of the secretome were assessed in an in vitro model of inflammation. Results from this study showed that aggregate-prepared secretome from hESC-MSCs was able to significantly decrease the secretion of TNF-α (301.7 ± 5.906, p strategy to increase immunomodulatory characteristics of hESC-MSCs.

  1. Dissipative particle dynamics simulations of deformation and aggregation of healthy and diseased red blood cells in a tube flow

    International Nuclear Information System (INIS)

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

    2014-01-01

    In this paper, we report simulation results assessing the deformation and aggregation of mixed healthy and malaria-infected red blood cells (RBCs) in a tube flow. A three dimensional particle model based on Dissipative Particle Dynamics (DPD) is developed to predict the tube flow containing interacting cells. The cells are also modelled by DPD, with a Morse potential to characterize the cell-cell interaction. As validation tests, a single RBC in a tube flow and two RBCs in a static flow are simulated to examine the cell deformation and intercellular interaction, respectively. The study of two cells, one healthy and the other malaria-infected RBCs in a tube flow demonstrates that the malaria-infected RBC (in the leading position along flow direction) has different effects on the healthy RBC (in the trailing position) at the different stage of parasite development or at the different capillary number. With parasitic development, the malaria-infected RBC gradually loses its deformability, and in turn the corresponding trailing healthy RBC also deforms less due to the intercellular interaction. With increasing capillary number, both the healthy and malaria-infected RBCs are likely to undergo an axisymmetric motion. The minimum intercellular distance becomes small enough so that rouleaux is easily formed, i.e., the healthy and malaria-infected RBCs are difficultly disaggregated

  2. Dissipative particle dynamics simulations of deformation and aggregation of healthy and diseased red blood cells in a tube flow

    Energy Technology Data Exchange (ETDEWEB)

    Ye, Ting; Phan-Thien, Nhan, E-mail: Nhan@nus.edu.sg; Khoo, Boo Cheong; Lim, Chwee Teck [Department of Mechanical Engineering, National University of Singapore, Singapore 119260 (Singapore)

    2014-11-15

    In this paper, we report simulation results assessing the deformation and aggregation of mixed healthy and malaria-infected red blood cells (RBCs) in a tube flow. A three dimensional particle model based on Dissipative Particle Dynamics (DPD) is developed to predict the tube flow containing interacting cells. The cells are also modelled by DPD, with a Morse potential to characterize the cell-cell interaction. As validation tests, a single RBC in a tube flow and two RBCs in a static flow are simulated to examine the cell deformation and intercellular interaction, respectively. The study of two cells, one healthy and the other malaria-infected RBCs in a tube flow demonstrates that the malaria-infected RBC (in the leading position along flow direction) has different effects on the healthy RBC (in the trailing position) at the different stage of parasite development or at the different capillary number. With parasitic development, the malaria-infected RBC gradually loses its deformability, and in turn the corresponding trailing healthy RBC also deforms less due to the intercellular interaction. With increasing capillary number, both the healthy and malaria-infected RBCs are likely to undergo an axisymmetric motion. The minimum intercellular distance becomes small enough so that rouleaux is easily formed, i.e., the healthy and malaria-infected RBCs are difficultly disaggregated.

  3. Mechanical Dissociation of Platelet Aggregates in Blood Stream

    Science.gov (United States)

    Hoore, Masoud; Fedosov, Dmitry A.; Gompper, Gerhard; Complex; Biological Fluids Group Team

    2017-11-01

    von Willebrand factor (VWF) and platelet aggregation is a key phenomenon in blood clotting. These aggregates form critically in high shear rates and dissolve reversibly in low shear rates. The emergence of a critical shear rate, beyond which aggregates form and below which they dissolve, has an interesting impact on aggregation in blood flow. As red blood cells (RBCs) migrate to the center of the vessel in blood flow, a RBC free layer (RBC-FL) is left close to the walls into which the platelets and VWFs are pushed back from the bulk flow. This margination process provides maximal VWF-platelet aggregation probability in the RBC-FL. Using mesoscale hydrodynamic simulations of aggregate dynamics in blood flow, it is shown that the aggregates form and grow in RBC-FL wherein shear rate is high for VWF stretching. By growing, the aggregates penetrate to the bulk flow and get under order of magnitude lower shear rates. Consequently, they dissolve and get back into the RBC-FL. This mechanical limitation for aggregates prohibits undesired thrombosis and vessel blockage by aggregates, while letting the VWFs and platelets to aggregate close to the walls where they are actually needed. The support by the DFG Research Unit FOR 1543 SHENC and CPU time Grant by the Julich Supercomputing Center are acknowledged.

  4. Estimation of Scatterer Diameter by Normalized Power Spectrum of High-Frequency Ultrasonic RF Echo for Assessment of Red Blood Cell Aggregation

    Science.gov (United States)

    Fukushima, Taku; Hasegawa, Hideyuki; Kanai, Hiroshi

    2011-07-01

    Red blood cell (RBC) aggregation, as one of the determinants of blood viscosity, plays an important role in blood rheology, including the condition of blood. RBC aggregation is induced by the adhesion of RBCs when the electrostatic repulsion between RBCs weakens owing to increases in protein and saturated fatty acid levels in blood, excessive RBC aggregation leads to various circulatory diseases. This study was conducted to establish a noninvasive quantitative method for assessment of RBC aggregation. The power spectrum of ultrasonic RF echoes from nonaggregating RBCs, which shows the frequency property of scattering, exhibits Rayleigh behavior. On the other hand, ultrasonic RF echoes from aggregating RBCs contain the components of reflection, which have no frequency dependence. By dividing the measured power spectrum of echoes from RBCs in the lumen by that of echoes from a posterior wall of the vein in the dorsum manus, the attenuation property of the propagating medium and the frequency responses of transmitting and receiving transducers are removed from the former spectrum. RBC aggregation was assessed by the diameter of a scatterer, which was estimated by minimizing the square difference between the measured normalized power spectrum and the theoretical power spectrum. In this study, spherical scatterers with diameters of 5, 11, 15, and 30 µm were measured in basic experiments. The estimated scatterer diameters were close to the actual diameters. Furthermore, the transient change of the scatterer diameters were measured in an in vivo experiment with respect to a 24-year-old healthy male during the avascularization using a cuff. The estimated diameters (12-22 µm) of RBCs during avascularization were larger than the diameters (4-8 µm) at rest and after recirculation. These results show the possibility of the use of the proposed method for noninvasive assessment of RBC aggregation.

  5. Mapuche Herbal Medicine Inhibits Blood Platelet Aggregation

    Directory of Open Access Journals (Sweden)

    Susan Skanderup Falkenberg

    2012-01-01

    Full Text Available 12 plant species traditionally used by the Mapuche people in Chile to treat wounds and inflammations have been evaluated for their direct blood platelet inhibition. Seven of the 12 tested plant species showed platelet inhibitory effect in sheep blood, and four of these were also able to inhibit the ADP- (5.0 μM and collagen- (2.0 μg/mL induced aggregations in human blood. These four species in respective extracts (in brackets were Blechnum chilense (MeOH, Luma apiculata (H2O, Amomyrtus luma (DCM : MeOH 1 : 1 and Cestrum parqui (DCM : MeOH 1 : 1. The platelet aggregating inhibitory effects of A. luma (DCM : MeOH 1 : 1, and L. apiculata (H2O were substantial and confirmed by inhibition of platelet surface activation markers.

  6. Mapuche herbal medicine inhibits blood platelet aggregation.

    Science.gov (United States)

    Falkenberg, Susan Skanderup; Tarnow, Inge; Guzman, Alfonso; Mølgaard, Per; Simonsen, Henrik Toft

    2012-01-01

    12 plant species traditionally used by the Mapuche people in Chile to treat wounds and inflammations have been evaluated for their direct blood platelet inhibition. Seven of the 12 tested plant species showed platelet inhibitory effect in sheep blood, and four of these were also able to inhibit the ADP- (5.0 μM) and collagen- (2.0 μg/mL) induced aggregations in human blood. These four species in respective extracts (in brackets) were Blechnum chilense (MeOH), Luma apiculata (H(2)O), Amomyrtus luma (DCM : MeOH 1 : 1) and Cestrum parqui (DCM : MeOH 1 : 1). The platelet aggregating inhibitory effects of A. luma (DCM : MeOH 1 : 1), and L. apiculata (H(2)O) were substantial and confirmed by inhibition of platelet surface activation markers.

  7. Mapuche Herbal Medicine Inhibits Blood Platelet Aggregation

    OpenAIRE

    Falkenberg, Susan Skanderup; Tarnow, Inge; Guzman, Alfonso; Mølgaard, Per; Simonsen, Henrik Toft

    2012-01-01

    12 plant species traditionally used by the Mapuche people in Chile to treat wounds and inflammations have been evaluated for their direct blood platelet inhibition. Seven of the 12 tested plant species showed platelet inhibitory effect in sheep blood, and four of these were also able to inhibit the ADP- (5.0??M) and collagen- (2.0??g/mL) induced aggregations in human blood. These four species in respective extracts (in brackets) were Blechnum chilense (MeOH), Luma apiculata (H2O), Amomyrtus l...

  8. Effects of Aggregation on Blood Sedimentation and Conductivity

    Science.gov (United States)

    Zhbanov, Alexander; Yang, Sung

    2015-01-01

    The erythrocyte sedimentation rate (ESR) test has been used for over a century. The Westergren method is routinely used in a variety of clinics. However, the mechanism of erythrocyte sedimentation remains unclear, and the 60 min required for the test seems excessive. We investigated the effects of cell aggregation during blood sedimentation and electrical conductivity at different hematocrits. A sample of blood was drop cast into a small chamber with two planar electrodes placed on the bottom. The measured blood conductivity increased slightly during the first minute and decreased thereafter. We explored various methods of enhancing or retarding the erythrocyte aggregation. Using experimental measurements and theoretical calculations, we show that the initial increase in blood conductivity was indeed caused by aggregation, while the subsequent decrease in conductivity resulted from the deposition of erythrocytes. We present a method for calculating blood conductivity based on effective medium theory. Erythrocytes are modeled as conducting spheroids surrounded by a thin insulating membrane. A digital camera was used to investigate the erythrocyte sedimentation behavior and the distribution of the cell volume fraction in a capillary tube. Experimental observations and theoretical estimations of the settling velocity are provided. We experimentally demonstrate that the disaggregated cells settle much slower than the aggregated cells. We show that our method of measuring the electrical conductivity credibly reflected the ESR. The method was very sensitive to the initial stage of aggregation and sedimentation, while the sedimentation curve for the Westergren ESR test has a very mild slope in the initial time. We tested our method for rapid estimation of the Westergren ESR. We show a correlation between our method of measuring changes in blood conductivity and standard Westergren ESR method. In the future, our method could be examined as a potential means of accelerating

  9. Changes of red blood cell aggregation parameters in a long-term follow-up of splenectomy, spleen-autotransplantation and partial or subtotal spleen resections in a canine model.

    Science.gov (United States)

    Miko, Iren; Nemeth, Norbert; Peto, Katalin; Furka, Andrea; Toth, Laszlo; Furka, Istvan

    2017-01-01

    Decrease or loss in splenic filtration function may influence the hemorheological state. To follow-up the long-term effects of splenectomy, spleen autotransplantation and spleen resections on red blood cell aggregation in a canine model. Beagle dogs were subjected to control (n = 6), splenectomy (SE, n = 4), spleen autotransplantation (AU, Furka's spleen-chip method, n = 8) or partial and subtotal spleen resection (n = 4/each) groups, and followed-up for 18 postoperative (p.o.) months. Erythrocyte aggregation was determined in parallel by light-transmittance aggregometry (Myrenne MA-1 aggregometer) and syllectometry (LoRRca). Erythrocyte aggregation decreased three months after splenectomy, with lower aggregation index and elongated aggregation time. It was more or less associated with relatively lower hematocrit and fibrinogen concentration. However, in autotransplantated animals a relatively higher fibrinogen did not increase the aggregation markedly. Spleen resection resulted in the most controversial red blood cell aggregation findings, and it seems, that the degree of the resection is an influencing factor. Splenectomy alters erythrocyte aggregation, spleen autotransplantation can be useful to preserve filtration function. However, the degree of restoration shows individual differences with a kind of 'functional periodicity'. Spleen resection controversially influences erythrocyte aggregation parameters. The subtotal resection is supposed to be worse than spleen autotransplantation.

  10. The proteome of neurofilament-containing protein aggregates in blood

    Directory of Open Access Journals (Sweden)

    Rocco Adiutori

    2018-07-01

    Full Text Available Protein aggregation in biofluids is a poorly understood phenomenon. Under normal physiological conditions, fluid-borne aggregates may contain plasma or cell proteins prone to aggregation. Recent observations suggest that neurofilaments (Nf, the building blocks of neurons and a biomarker of neurodegeneration, are included in high molecular weight complexes in circulation. The composition of these Nf-containing hetero-aggregates (NCH may change in systemic or organ-specific pathologies, providing the basis to develop novel disease biomarkers. We have tested ultracentrifugation (UC and a commercially available protein aggregate binder, Seprion PAD-Beads (SEP, for the enrichment of NCH from plasma of healthy individuals, and then characterised the Nf content of the aggregate fractions using gel electrophoresis and their proteome by mass spectrometry (MS. Western blot analysis of fractions obtained by UC showed that among Nf isoforms, neurofilament heavy chain (NfH was found within SDS-stable high molecular weight aggregates. Shotgun proteomics of aggregates obtained with both extraction techniques identified mostly cell structural and to a lesser extent extra-cellular matrix proteins, while functional analysis revealed pathways involved in inflammatory response, phagosome and prion-like protein behaviour. UC aggregates were specifically enriched with proteins involved in endocrine, metabolic and cell-signalling regulation. We describe the proteome of neurofilament-containing aggregates isolated from healthy individuals biofluids using different extraction methods.

  11. Aluminum induces lipid peroxidation and aggregation of human blood platelets

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    T.J.C. Neiva

    1997-05-01

    Full Text Available Aluminum (Al3+ intoxication is thought to play a major role in the development of Alzheimer's disease and in certain pathologic manifestations arising from long-term hemodialysis. Although the metal does not present redox capacity, it can stimulate tissue lipid peroxidation in animal models. Furthermore, in vitro studies have revealed that the fluoroaluminate complex induces diacylglycerol formation, 43-kDa protein phosphorylation and aggregation. Based on these observations, we postulated that Al3+-induced blood platelet aggregation was mediated by lipid peroxidation. Using chemiluminescence (CL of luminol as an index of total lipid peroxidation capacity, we established a correlation between lipid peroxidation capacity and platelet aggregation. Al3+ (20-100 µM stimulated CL production by human blood platelets as well as their aggregation. Incubation of the platelets with the antioxidants nor-dihydroguaiaretic acid (NDGA (100 µM and n-propyl gallate (NPG (100 µM, inhibitors of the lipoxygenase pathway, completely prevented CL and platelet aggregation. Acetyl salicylic acid (ASA (100 µM, an inhibitor of the cyclooxygenase pathway, was a weaker inhibitor of both events. These findings suggest that Al3+ stimulates lipid peroxidation and the lipoxygenase pathway in human blood platelets thereby causing their aggregation

  12. 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 ...

  13. Influence of caffeine on blood pressure and platelet aggregation

    Directory of Open Access Journals (Sweden)

    José Wilson S. Cavalcante

    2000-08-01

    Full Text Available OBJECTIVE: Studies have demonstrated that methylxanthines, such as caffeine, are A1 and A2 adenosine receptor antagonists found in the brain, heart, lungs, peripheral vessels, and platelets. Considering the high consumption of products with caffeine in their composition, in Brazil and throughout the rest of the world, the authors proposed to observe the effects of this substance on blood pressure and platelet aggregation. METHODS: Thirteen young adults, ranging from 21 to 27 years of age, participated in this study. Each individual took 750mg/day of caffeine (250mg tid, over a period of seven days. The effects on blood pressure were analyzed through the pressor test with handgrip, and platelet aggregation was analyzed using adenosine diphosphate, collagen, and adrenaline. RESULTS: Diastolic pressure showed a significant increase 24 hours after the first intake (p<0.05. This effect, however, disappeared in the subsequent days. The platelet aggregation tests did not reveal statistically significant alterations, at any time during the study. CONCLUSION: The data suggest that caffeine increases diastolic blood pressure at the beginning of caffeine intake. This hypertensive effect disappears with chronic use. The absence of alterations in platelet aggregation indicates the need for larger randomized studies.

  14. Low White Blood Cell Count

    Science.gov (United States)

    Symptoms Low white blood cell count By Mayo Clinic Staff A low white blood cell count (leukopenia) is a decrease ... of white blood cell (neutrophil). The definition of low white blood cell count varies from one medical ...

  15. Blood Cell Interactions and Segregation in Flow

    OpenAIRE

    Munn, Lance L.; Dupin, Michael M.

    2008-01-01

    For more than a century, pioneering researchers have been using novel experimental and computational approaches to probe the mysteries of blood flow. Thanks to their efforts, we know that blood cells generally prefer to migrate to the axis of flow, that red and white cells segregate in flow, and that cell deformability and their tendency to reversibly aggregate contribute to the non-Newtonian nature of this unique fluid. All of these properties have beneficial physiological consequences, allo...

  16. Blood cell interactions and segregation in flow.

    Science.gov (United States)

    Munn, Lance L; Dupin, Michael M

    2008-04-01

    For more than a century, pioneering researchers have been using novel experimental and computational approaches to probe the mysteries of blood flow. Thanks to their efforts, we know that blood cells generally prefer to migrate to the axis of flow, that red and white cells segregate in flow, and that cell deformability and their tendency to reversibly aggregate contribute to the non-Newtonian nature of this unique fluid. All of these properties have beneficial physiological consequences, allowing blood to perform a variety of critical functions. Our current understanding of these unusual flow properties of blood have been made possible by the ingenuity and diligence of a number of researchers, including Harry Goldsmith, who developed novel technologies to visualize and quantify the flow of blood at the level of individual cells. Here we summarize efforts in our lab to continue this tradition and to further our understanding of how blood cells interact with each other and with the blood vessel wall.

  17. Live Cell Characterization of DNA Aggregation Delivered through Lipofection.

    Science.gov (United States)

    Mieruszynski, Stephen; Briggs, Candida; Digman, Michelle A; Gratton, Enrico; Jones, Mark R

    2015-05-27

    DNA trafficking phenomena, such as information on where and to what extent DNA aggregation occurs, have yet to be fully characterised in the live cell. Here we characterise the aggregation of DNA when delivered through lipofection by applying the Number and Brightness (N&B) approach. The N&B analysis demonstrates extensive aggregation throughout the live cell with DNA clusters in the extremity of the cell and peri-nuclear areas. Once within the nucleus aggregation had decreased 3-fold. In addition, we show that increasing serum concentration of cell media results in greater cytoplasmic aggregation. Further, the effects of the DNA fragment size on aggregation was explored, where larger DNA constructs exhibited less aggregation. This study demonstrates the first quantification of DNA aggregation when delivered through lipofection in live cells. In addition, this study has presents a model for alternative uses of this imaging approach, which was originally developed to study protein oligomerization and aggregation.

  18. Donating Peripheral Blood Stem Cells

    Science.gov (United States)

    ... Print this page My Cart Donating peripheral blood stem cells Peripheral blood stem cell (PBSC) donation is a nonsurgical procedure to collect ... Donating bone marrow Donor experiences videos Peripheral blood stem cell (PBSC) donation is one of two methods of ...

  19. Radiolabelled blood cells

    Energy Technology Data Exchange (ETDEWEB)

    Lavender, J.P.

    1986-12-01

    After the introduction of gamma-emitting labels for blood-cells the use of radio-labelled blood cells is not only limited to kinetics of blood cells but it is also possible to localise inflammations, abscesses and thrombus. The most commonly applied label for red cells is Tc-99m. The most widely used technique for labelling granulocytes or platelets is In-111-oxine. In future the labelling of blood cells will be more simple and more specific due to monoclonal antibodies onto the platelet or the granulocyte cell surface. Labelled red cells have their main application in blood-pool imaging and in localisation of gastrointestinal bleeding. Besides the determination of the platelet life-span in haematologic disorders labelled platelets allow to localise thrombus and to show abnormal vasculature in the rejecting kidney. The commonest application for In-111-oxin labelled granulocytes is to show abdominal inflammations to localise inflamed bowel segments and to assess the inflammatory activity in chronic inflammatory bowel diseases. Moreover brain abscesses, bone sepsis and lung sepsis can be identified.

  20. Whole blood of mammalian species in the oscillating shear field: influence of erythrocyte aggregation

    Science.gov (United States)

    Windberger, U.; Pöschl, Ch; Peters, S.; Huber, J.; van den Hoven, R.

    2017-02-01

    This is the rheologicalanalysis of mammalian blood of species with a high (horse), medium (man), and low (sheep) erythrocyte (RBC) aggregability by small amplitude oscillation technique. Amplitude and frequency sweep tests in linear mode were performed with blood from healthy adult volunteers, horses, and sheep in CSS-mode. Blood samples were hematocrit (HCT) adjusted (40%, 50%, 60%) and tested at 7°C, 22°C, and 37°C. Storage modulus (G‧) increased with HCT and decreased with temperature in each species, but the gradient of this increase was species-specific. The lower dependency of G‧ on the equine HCT value could be a benefit during physical performance when high numbers of RBCs are released from the spleen in the horse. In sheep, a HCT-threshold had to be overcome before elasticity of the blood sample could be measured, suggesting that the cohesive forces between RBCs, and between RBCs and plasma molecules must be very low. The frequencies for tests under quasi-staticcondition were in a narrow range around the physiologic heart rate of the species. In horse, time-dependent influences concurred at frequencies lower than 3 rad.s-1 probably due to sedimentation of RBC aggregates. In conclusion, elasticity of blood depends not only on the amount of blood cells, but also on their mechanical and functional properties.

  1. Multiple and Periodic Measurement of RBC Aggregation and ESR in Parallel Microfluidic Channels under On-Off Blood Flow Control

    Directory of Open Access Journals (Sweden)

    Yang Jun Kang

    2018-06-01

    Full Text Available Red blood cell (RBC aggregation causes to alter hemodynamic behaviors at low flow-rate regions of post-capillary venules. Additionally, it is significantly elevated in inflammatory or pathophysiological conditions. In this study, multiple and periodic measurements of RBC aggregation and erythrocyte sedimentation rate (ESR are suggested by sucking blood from a pipette tip into parallel microfluidic channels, and quantifying image intensity, especially through single experiment. Here, a microfluidic device was prepared from a master mold using the xurography technique rather than micro-electro-mechanical-system fabrication techniques. In order to consider variations of RBC aggregation in microfluidic channels due to continuous ESR in the conical pipette tip, two indices (aggregation index (AI and erythrocyte-sedimentation-rate aggregation index (EAI are evaluated by using temporal variations of microscopic, image-based intensity. The proposed method is employed to evaluate the effect of hematocrit and dextran solution on RBC aggregation under continuous ESR in the conical pipette tip. As a result, EAI displays a significantly linear relationship with modified conventional ESR measurement obtained by quantifying time constants. In addition, EAI varies linearly within a specific concentration of dextran solution. In conclusion, the proposed method is able to measure RBC aggregation under continuous ESR in the conical pipette tip. Furthermore, the method provides multiple data of RBC aggregation and ESR through a single experiment. A future study will involve employing the proposed method to evaluate biophysical properties of blood samples collected from cardiovascular diseases.

  2. p53 Aggregates penetrate cells and induce the co-aggregation of intracellular p53.

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    Karolyn J Forget

    Full Text Available Prion diseases are unique pathologies in which the infectious particles are prions, a protein aggregate. The prion protein has many particular features, such as spontaneous aggregation, conformation transmission to other native PrP proteins and transmission from an individual to another. Protein aggregation is now frequently associated to many human diseases, for example Alzheimer's disease, Parkinson's disease or type 2 diabetes. A few proteins associated to these conformational diseases are part of a new category of proteins, called prionoids: proteins that share some, but not all, of the characteristics associated with prions. The p53 protein, a transcription factor that plays a major role in cancer, has recently been suggested to be a possible prionoid. The protein has been shown to accumulate in multiple cancer cell types, and its aggregation has also been reproduced in vitro by many independent groups. These observations suggest a role for p53 aggregates in cancer development. This study aims to test the «prion-like» features of p53. Our results show in vitro aggregation of the full length and N-terminally truncated protein (p53C, and penetration of these aggregates into cells. According to our findings, the aggregates enter cells using macropinocytosis, a non-specific pathway of entry. Lastly, we also show that once internalized by the cell, p53C aggregates can co-aggregate with endogenous p53 protein. Together, these findings suggest prion-like characteristics for p53 protein, based on the fact that p53 can spontaneously aggregate, these aggregates can penetrate cells and co-aggregate with cellular p53.

  3. 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

  4. Tracking hypoxic signaling within encapsulated cell aggregates.

    Science.gov (United States)

    Skiles, Matthew L; Sahai, Suchit; Blanchette, James O

    2011-12-16

    , is therefore reduced and limited by diffusion. This reduced oxygen availability may especially impact β-cells whose insulin secretory function is highly dependent on oxygen. Capsule composition and geometry will also impact diffusion rates and lengths for oxygen. Therefore, we also describe a technique for identifying hypoxic cells within our PEG capsules. Infection of the cells with a recombinant adenovirus allows for a fluorescent signal to be produced when intracellular hypoxia-inducible factor (HIF) pathways are activated. As HIFs are the primary regulators of the transcriptional response to hypoxia, they represent an ideal target marker for detection of hypoxic signaling. This approach allows for easy and rapid detection of hypoxic cells. Briefly, the adenovirus has the sequence for a red fluorescent protein (Ds Red DR from Clontech) under the control of a hypoxia-responsive element (HRE) trimer. Stabilization of HIF-1 by low oxygen conditions will drive transcription of the fluorescent protein (Figure 1). Additional details on the construction of this virus have been published previously. The virus is stored in 10% glycerol at -80° C as many 150 μL aliquots in 1.5 mL centrifuge tubes at a concentration of 3.4 x 10(10) pfu/mL. Previous studies in our lab have shown that MIN6 cells encapsulated as aggregates maintain their viability throughout 4 weeks of culture in 20% oxygen. MIN6 aggregates cultured at 2 or 1% oxygen showed both signs of necrotic cells (still about 85-90% viable) by staining with ethidium bromide as well as morphological changes relative to cells in 20% oxygen. The smooth spherical shape of the aggregates displayed at 20% was lost and aggregates appeared more like disorganized groups of cells. While the low oxygen stress does not cause a pronounced drop in viability, it is clearly impacting MIN6 aggregation and function as measured by glucose-stimulated insulin secretion. Western blot analysis of encapsulated cells in 20% and 1% oxygen also

  5. Aggregation activity of blood formed elements in patients with type 1 and type 2 diabetes mellitus

    OpenAIRE

    Boris Il'ich Kuznik; Yuriy Antonovich Vitkovskiy; Marina Yur'evna Zakharova; Natal'ya Nikolaevna Klyuchereva; Ol'ga Sergeevna Rodnina; Aleksey Vladimirovich Solpov

    2012-01-01

    Aims. To assess differences in blood formed elements aggregation activity in patients with type 1 (T1) and type 2 (T2) diabetes mellitus (DM). Materials and methods. We studied blood samples from 88 patients with T1 and T2 DM. Platelet aggregation activity was assessed by means of «Biola» aggregometer; we also determined platelet-lymphocyte and leucocyte-erythrocyte adhesion intensity. Results. We show that spontaneous platelet aggregation is markedly increased in patients with T1...

  6. Experiment on aggregation of red cells under microgravity on STS 51-C

    Science.gov (United States)

    Dintenfass, L.; Osman, P.; Maguire, B.; Jedrzejczyk, H.

    Kinetics and morphology of aggregation of red cells were studied using automatic slit-capillary photo-viscometers, one situated on the middeck of the space shuttle `Discovery', and the other in the ground laboratory at KSC. Experiments were run simultaneously, blood samples being adjusted to haematocrit of 0.30 using native plasma, at temp. of 25°C, and anticoagulated by EDTA. Donors included patients with myocardial infarction, insulin-dependent diabetes, hyperlipidaemia and hypertension. Macro and microphotographs were obtained during flow and statis. There was a striking difference in the morphology of aggregates formed in space and on the ground. Aggregates formed under zero gravity showed rouleaux formation, while the same blood samples showed severe clumping on the ground, in all patients blood. Normal blood showed rouleaux on the ground, but a random swarm-like pattern in space. The shape of the red cells remained normal under zero gravity.

  7. Macromolecular cell surface engineering for accelerated and reversible cellular aggregation.

    OpenAIRE

    Amaral, A. J.; Pasparakis, G.

    2015-01-01

    We report the synthesis of two simple copolymers that induce rapid cell aggregation within minutes in a fully reversible manner. The polymers can act as self-supporting "cellular glues" or as "drivers" of 3D cell spheroids/aggregates formation at minute concentrations.

  8. Combined modeling of cell aggregation and adhesion mediated by receptor–ligand interactions under shear flow

    Directory of Open Access Journals (Sweden)

    Yu Du

    2015-11-01

    Full Text Available Blood cell aggregation and adhesion to endothelial cells under shear flow are crucial to many biological processes such as thrombi formation, inflammatory cascade, and tumor metastasis, in which these cellular interactions are mainly mediated by the underlying receptor–ligand bindings. While theoretical modeling of aggregation dynamics and adhesion kinetics of interacting cells have been well studied separately, how to couple these two processes remains unclear. Here we develop a combined model that couples cellular aggregation dynamics and adhesion kinetics under shear flow. The impacts of shear rate (or shear stress and molecular binding affinity were elucidated. This study provides a unified model where the action of a fluid flow drives cell aggregation and adhesion under the modulations of the mechanical shear flow and receptor–ligand interaction kinetics. It offers an insight into understanding the relevant biological processes and functions.

  9. Bifenthrin activates homotypic aggregation in human T-cell lines.

    Science.gov (United States)

    Hoffman, Nataly; Tran, Van; Daniyan, Anthony; Ojugbele, Olutosin; Pryor, Stephen C; Bonventre, Josephine A; Flynn, Katherine; Weeks, Benjamin S

    2006-03-01

    Here, we addressed the concern that, despite the lack of overt toxicity, exposure to low levels of the common household pyrethroid pesticide, bifenthrin, could cause harm to the immune system. To do this, we measure the effect of bifenthrin on phytohemagglutinin (PHA) activation of homotypic aggregation in human T-cell lines. The human CD4+ H9, and Jurkat cell lines and the human promonocyte U937 cell line, were exposed to varying concentrations of bifenthrin. Cell viability was determined using the AlmarBlue Toxicity Assay. Concentrations of bifenthrin which did not reduce cell viability were determined and these concentrations were tested for the effect of bifenthrin on PHA-mediated homotypic aggregation. Blocking antibodies to ICAM and LFA-1 were used to disrupt aggregation and a nonspecific IgG was used as a control. Bifenthrin was found to be nontoxic at concentrations ranging from 10(-4) to 10(-13) M. Bifenthrin did not inhibit PHA induced cell aggregation in all cell lines tested. However, at 10(-4) M, bifenthrin to form aggregates stimulated homotypic aggregation in the H9 and Jurkat T-cell lines. The bifenthrin-induced aggregate formation, like that seen with PHA, was blocked by treating the cells with antibodies to either LFA-1 or ICAM. The results here show that bifenthrin activates T-cell function by stimulating ICAM/LFA-1 mediated homotypic aggregation. This data suggests that exposure to bifenthrin, even at "acceptable" limits, can increase the risk for and frequency of inflammatory responses and diseases such as asthma.

  10. Platelet aggregation and quality control of platelet concentrates produced in the Amazon Blood Bank

    Directory of Open Access Journals (Sweden)

    Maria José Dantas Coêlho

    2011-01-01

    Full Text Available BACKGROUND: The study of platelet aggregation is essential to assess in vitro platelet function by different platelet activation pathways. OBJECTIVE: To assess aggregation and biochemical parameters of random platelet concentrates produced at the Fundação HEMOAM using the quality control tests defined by law. METHODS: Whole blood samples from 80 donors and the respective platelet concentrate units were tested. Platelet concentrates were tested (platelet count, aggregation and pH on days 1, 3 and 5 of storage. Additionally a leukocyte count was done only on day 1 and microbiological tests on day 5 of storage. Collagen and adenosine diphosphate were used as inducing agonists for platelet aggregation testing. RESULTS: Donor whole blood had normal aggregation (aggregation with adenosine diphosphate = 67% and with collagen = 78%. The median aggregation in platelet concentrates with adenosine diphosphate was low throughout storage (18% on day 1, 7% on day 3 and 6% on day 5 and the median aggregation with collagen was normal only on day 1 and low thereafter (54.4% on day 1, 20.5% on day 3 and 9% on day 5. CONCLUSION: Although the results were within the norms required by law, platelet concentrates had low aggregation rates. We suggest the inclusion of a functional assessment test for the quality control of platelet concentrates for a more effective response to platelet replacement therapy.

  11. 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.

  12. Aggregate formation affects ultrasonic disruption of microalgal cells.

    Science.gov (United States)

    Wang, Wei; Lee, Duu-Jong; Lai, Juin-Yih

    2015-12-01

    Ultrasonication is a cell disruption process of low energy efficiency. This study dosed K(+), Ca(2+) and Al(3+) to Chlorella vulgaris cultured in Bold's Basal Medium at 25°C and measured the degree of cell disruption under ultrasonication. Adding these metal ions yielded less negatively charged surfaces of cells, while with the latter two ions large and compact cell aggregates were formed. The degree of cell disruption followed: control=K(+)>Ca(2+)>Al(3+) samples. Surface charges of cells and microbubbles have minimal effects on the microbubble number in the proximity of the microalgal cells. Conversely, cell aggregates with large size and compact interior resist cell disruption under ultrasonication. Staining tests revealed high diffusional resistance of stains over the aggregate interior. Microbubbles may not be effective generated and collapsed inside the compact aggregates, hence leading to low cell disruption efficiencies. Effective coagulation/flocculation in cell harvesting may lead to adverse effect on subsequent cell disruption efficiency. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Symbiotic Cell Differentiation and Cooperative Growth in Multicellular Aggregates.

    Directory of Open Access Journals (Sweden)

    Jumpei F Yamagishi

    2016-10-01

    Full Text Available As cells grow and divide under a given environment, they become crowded and resources are limited, as seen in bacterial biofilms and multicellular aggregates. These cells often show strong interactions through exchanging chemicals, as evident in quorum sensing, to achieve mutualism and division of labor. Here, to achieve stable division of labor, three characteristics are required. First, isogenous cells differentiate into several types. Second, this aggregate of distinct cell types shows better growth than that of isolated cells without interaction and differentiation, by achieving division of labor. Third, this cell aggregate is robust with respect to the number distribution of differentiated cell types. Indeed, theoretical studies have thus far considered how such cooperation is achieved when the ability of cell differentiation is presumed. Here, we address how cells acquire the ability of cell differentiation and division of labor simultaneously, which is also connected with the robustness of a cell society. For this purpose, we developed a dynamical-systems model of cells consisting of chemical components with intracellular catalytic reaction dynamics. The reactions convert external nutrients into internal components for cellular growth, and the divided cells interact through chemical diffusion. We found that cells sharing an identical catalytic network spontaneously differentiate via induction from cell-cell interactions, and then achieve division of labor, enabling a higher growth rate than that in the unicellular case. This symbiotic differentiation emerged for a class of reaction networks under the condition of nutrient limitation and strong cell-cell interactions. Then, robustness in the cell type distribution was achieved, while instability of collective growth could emerge even among the cooperative cells when the internal reserves of products were dominant. The present mechanism is simple and general as a natural consequence of

  14. Changes in blood aggregation with differences in molecular weight and degree of deacetylation of chitosan

    International Nuclear Information System (INIS)

    Hattori, Hidemi; Ishihara, Masayuki

    2015-01-01

    Because the molecular weight (Mw) and degree of deacetylation (DDA) of chitosan can vary depending on the purification method, the identification of appropriate chitosan structures is important for developing more effective hemostatic agents. In this study, the influence of varying Mw and DDA of chitosan on blood aggregation was characterized by 10 types of chitosan with different Mw and DDA, including oligomers. The highest aggregation of whole blood, washed erythrocytes and platelets in platelet-rich plasma (PRP) were observed in chitosan with Mw of 8.6 kDa or more and with DDA of 75 to 88%. However, chitosan with too high Mw (247 kDa) inhibited the aggregation of whole blood, washed erythrocytes and PRP at high chitosan concentration. At certain concentrations, chitosan with 75–85% DDA and 50–190 kDa and chitosan with 87.6% DDA and 247 kDa both aggregated proteins in PRP. Chitosan oligomer did not affect blood aggregation. The results suggested that the aggregation by chitosan depended on the interaction of positively charged chitosan with negatively charged erythrocytes, platelets and plasma protein. It seemed that a suitable balance of positive charge in chitosan and negative charge in hemocytes and some kinds of proteins was important. To develop a hemostatic with effective blood aggregation, the chitosan should not be limited to a single Mw and a single DDA but may be a mixed chitosan with wide range of Mw (8.6–247 kDa) and DDA of 75 to 88%. (paper)

  15. Aggregation activity of blood formed elements in patients with type 1 and type 2 diabetes mellitus

    Directory of Open Access Journals (Sweden)

    Boris Il'ich Kuznik

    2012-06-01

    Full Text Available Aims. To assess differences in blood formed elements aggregation activity in patients with type 1 (T1 and type 2 (T2 diabetes mellitus(DM. Materials and methods. We studied blood samples from 88 patients with T1 and T2 DM. Platelet aggregation activity was assessed bymeans of ?Biola? aggregometer; we also determined platelet-lymphocyte and leucocyte-erythrocyte adhesion intensity. Results. We show that spontaneous platelet aggregation is markedly increased in patients with T1DM but remains normal or slightlyelevated in case of T2DM. In blood from patients with T2DM platelet aggregation in response to ADP, epinephrine, ristomycineand contact with collagen was generally increased, whereas in T1DM we often observed its secondary reduction. Data on plateletlymphocyteadhesion in T1DM is controversial, but in T2DM this process seems to be significantly suppressed. Quantity of leucocyteerythrocyteaggregates was sharply increased in both T1DM and T2DM. Conclusion. We've determined significant difference in blood formed elements aggregation activity between patients with T1 and T2 DM.

  16. Short-lived, transitory cell-cell interactions foster migration-dependent aggregation.

    Directory of Open Access Journals (Sweden)

    Melissa D Pope

    Full Text Available During embryonic development, motile cells aggregate into cohesive groups, which give rise to tissues and organs. The role of cell migration in regulating aggregation is unclear. The current paradigm for aggregation is based on an equilibrium model of differential cell adhesivity to neighboring cells versus the underlying substratum. In many biological contexts, however, dynamics is critical. Here, we provide evidence that multicellular aggregation dynamics involves both local adhesive interactions and transport by cell migration. Using time-lapse video microscopy, we quantified the duration of cell-cell contacts among migrating cells that collided and adhered to another cell. This lifetime of cell-cell interactions exhibited a monotonic decreasing dependence on substratum adhesivity. Parallel quantitative measurements of cell migration speed revealed that across the tested range of adhesive substrata, the mean time needed for cells to migrate and encounter another cell was greater than the mean adhesion lifetime, suggesting that aggregation dynamics may depend on cell motility instead of the local differential adhesivity of cells. Consistent with this hypothesis, aggregate size exhibited a biphasic dependence on substratum adhesivity, matching the trend we observed for cell migration speed. Our findings suggest a new role for cell motility, alongside differential adhesion, in regulating developmental aggregation events and motivate new design principles for tuning aggregation dynamics in tissue engineering applications.

  17. A microwell cell culture platform for the aggregation of pancreatic β-cells.

    Science.gov (United States)

    Bernard, Abigail B; Lin, Chien-Chi; Anseth, Kristi S

    2012-08-01

    Cell-cell contact between pancreatic β-cells is important for maintaining survival and normal insulin secretion. Various techniques have been developed to promote cell-cell contact between β-cells, but a simple yet robust method that affords precise control over three-dimensional (3D) β-cell cluster size has not been demonstrated. To address this need, we developed a poly(ethylene glycol) (PEG) hydrogel microwell platform using photolithography. This microwell cell-culture platform promotes the formation of 3D β-cell aggregates of defined sizes from 25 to 210 μm in diameter. Using this platform, mouse insulinoma 6 (MIN6) β-cells formed aggregates with cell-cell adherin junctions. These naturally formed cell aggregates with controllable sizes can be removed from the microwells for macroencapsulation, implantation, or other biological assays. When removed and subsequently encapsulated in PEG hydrogels, the aggregated cell clusters demonstrated improved cellular viability (>90%) over 7 days in culture, while the β-cells encapsulated as single cells maintained only 20% viability. Aggregated MIN6 cells also exhibited more than fourfold higher insulin secretion in response to a glucose challenge compared with encapsulated single β-cells. Further, the cell aggregates stained positively for E-cadherin, indicative of the formation of cell junctions. Using this hydrogel microwell cell-culture method, viable and functional β-cell aggregates of specific sizes were created, providing a platform from which other biologically relevant questions may be answered.

  18. First haemorheological experiment on NASA space shuttle 'Discovery' STS 51-C: aggregation of red cells.

    Science.gov (United States)

    Dintenfass, L; Osman, P D; Jedrzejczyk, H

    1985-01-01

    The 'secret' D.O.D. Mission on flight STS 51-C also carried nearly 100 kg of automated instrumentation of the Australian experiment on aggregation of red cells ("ARC"). The automated Slit-Capillary Photo Viscometer contained blood samples from subjects with history of coronary heart disease, cancer of the colon, insulin-dependent diabetes, etc., as well as normals. The experiment ran for nine hours, according to the program of its microcomputers. When shuttle landed and instrumentation recovered and opened in the presence of NASA quality control officers, it was obvious that experiment was a success. Tentative and preliminary results can be summarized as follows: red cells did not change shape under zero gravity; red cells do aggregate under zero gravity, although the size of aggregates is smaller than on the ground; the morphology of aggregates of red cells appears to be of rouleaux type under zero gravity, notwithstanding the fact that pathological blood was used. These results will have to be confirmed in the future flights. The background and history of development of the project are described, and put into context of our general haemorheological studies.

  19. Measurement of blood coagulation with considering RBC aggregation through a microchip-based light transmission aggregometer.

    Science.gov (United States)

    Lim, Hyunjung; Nam, Jeonghun; Xue, Shubin; Shin, Sehyun

    2011-01-01

    Even though blood coagulation can be tested by various methods and techniques, the effect of RBC aggregation on blood coagulation is not fully understood. The present study monitored clot formation in a microchip-based light transmission aggregometer. Citrated blood samples with and without the addition of calcium ion solution were initially disaggregated by rotating a stirrer in the microchip. After abrupt stop of the rotating stirrer, the transmitted light intensity over time was recorded. The syllectogram (light intensity vs. time graph) manifested a rapid increase that is associated with RBC aggregation followed by a decrease that is associated with blood coagulation. The time to reach the peak point was used as a new index of coagulation time (CT) and ranged from 200 to 500 seconds in the present measurements. The CT was inversely proportional to the concentration of fibrinogen, which enhances RBC aggregation. In addition, the CT was inversely proportional to the hematocrit, which is similar to the case of the prothrombin time (PT), as measured by a commercial coagulometer. Thus, we carefully concluded that RBC aggregation should be considered in tests of blood coagulation.

  20. Interstitial Cells of Blood Vessels

    Directory of Open Access Journals (Sweden)

    Vladimír Pucovský

    2010-01-01

    Full Text Available Blood vessels are made up of several distinct cell types. Although it was originally thought that the tunica media of blood vessels was composed of a homogeneous population of fully differentiated smooth muscle cells, more recent data suggest the existence of multiple smooth muscle cell subpopulations in the vascular wall. One of the cell types contributing to this heterogeneity is the novel, irregularly shaped, noncontractile cell with thin processes, termed interstitial cell, found in the tunica media of both veins and arteries. While the principal role of interstitial cells in veins seems to be pacemaking, the role of arterial interstitial cells is less clear. This review summarises the knowledge of the functional and structural properties of vascular interstitial cells accumulated so far, offers hypotheses on their physiological role, and proposes directions for future research.

  1. Flavonoids purified from parsley inhibit human blood platelet aggregation and adhesion to collagen under flow.

    Science.gov (United States)

    Gadi, Dounia; Bnouham, Mohamed; Aziz, Mohammed; Ziyyat, Abderrahim; Legssyer, Abdelkhaleq; Bruel, Arlette; Berrabah, Mohamed; Legrand, Chantal; Fauvel-Lafeve, Françoise; Mekhfi, Hassane

    2012-08-10

    Blood platelets are directly involved in both haemostatic and pathologic thrombotic processes, through their adhesion, secretion and aggregation. In this study, we investigated the effect of genins (aglycone flavonoids without sugar group) isolated from parsley (Petroselinum crispum) leaves in vitro on human platelet aggregation and adhesion to a collagen-coated surface under physiologic flow conditions. The aggregation and adhesion studies were monitored after pre-incubation of platelets with genins. Genins inhibited dose dependently aggregation induced by thrombin, ADP and collagen. The strongest effect was observed in collagen induced aggregation (IC50 = 0.08 ± 0.01 mg/ml). The HPLC identification of genins compounds revealed the presence of keampferol, apigenin and other not identified compounds. The aggregation tests showed that these compounds have anti-aggregating activity. In addition, adhesion of human platelets to collagen was greatly decreased (over 75 %) by genins (0.3 mg/ml). While the mechanism by which genins act is unclear, we suggest that these compounds may interfere with a multiple target step in the haemostasis process. These results show that genins isolated from parsley has a potent antiplatelet activity. It may be an important source of beneficial antiplatelet compounds that decrease thrombosis and cardiovascular diseases.

  2. Time dependent variation of human blood conductivity as a method for an estimation of RBC aggregation

    Czech Academy of Sciences Publication Activity Database

    Antonova, N.; Říha, Pavel; Ivanov, I.

    2008-01-01

    Roč. 39, č. 1 (2008), s. 69-78 ISSN 1386-0291 Institutional research plan: CEZ:AV0Z20600510 Keywords : RBC aggregation * blood conductivity * low shear rate viscometry Subject RIV: BO - Biophysics Impact factor: 1.814, year: 2008

  3. Reference range determination for whole-blood platelet aggregation using the Multiplate analyzer

    NARCIS (Netherlands)

    Peerschke, Ellinor I. B.; Castellone, Donna D.; Stroobants, A. K.; Francis, John

    2014-01-01

    To develop reference ranges for platelet aggregation using the Multiplate analyzer (Roche Diagnostics, Mannheim, Germany) in blood anticoagulated with sodium citrate (Na-citrate), lithium heparin (Li-heparin), or hirudin. The study was performed at three sites on consented, healthy adults (n = 193)

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

    NARCIS (Netherlands)

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

    2010-01-01

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

  5. The rheologic properties of red blood cells processed by 2 different types of cell savers, and its effects on microcirculatory blood flow and tissue oxygenation in vivo.

    NARCIS (Netherlands)

    Scheeren, Thomas; de Lange, S.; Martinez, A.; Hagenaars, Johanna A. M.; Ben Ayad, N.; de Vries, Hans

    2016-01-01

    Introduction: Cell savers (CS) reduce the percentage of patients who need blood products during cardiac surgery. While some CS use discontinuous blood processing with a spinning bowl, others use continuous blood processing based on the elutriation principle. Both may influence aggregation and

  6. Universal timescales in the rheology of spheroid cell aggregates

    Science.gov (United States)

    Yu, Miao; Mahtabfar, Aria; Beleen, Paul; Foty, Ramsey; Zahn, Jeffrey; Shreiber, David; Liu, Liping; Lin, Hao

    2017-11-01

    The rheological properties of tissue play important roles in key biological processes including embryogenesis, cancer metastasis, and wound healing. Spheroid cell aggregate is a particularly interesting model system for the study of these phenomena. In the long time, they behave like drops with a surface tension. In the short, viscoelasticity also needs to be considered. In this work, we discover two coupled and universal timescales for spheroid aggregates. A total of 12 aggregate types (total aggregate number n =290) derived from L and GBM (glioblastoma multiforme) cells are studied with microtensiometer to obtain their surface tension. They are also allowed to relax upon release of the compression forces. The two timescales are observed during the relaxation process; their values do not depend on compression time nor the degree of deformation, and are consistent among all 12 types. Following prior work (Yu et al., Phys. Rev. Lett., 115:128303; Liu et al., J. Mech. Phys. Solids, 98:309-329) we use a rigorous mathematical theory to interpret the results, which reveals intriguing properties of the aggregates on both tissue and cellular levels. The mechanics of multicellular organization reflects both complexity and regularity due to strong active regulation.

  7. Nattokinase improves blood flow by inhibiting platelet aggregation and thrombus formation.

    Science.gov (United States)

    Jang, Ja-Young; Kim, Tae-Su; Cai, Jingmei; Kim, Jihyun; Kim, Youngeun; Shin, Kyungha; Kim, Kwang Sei; Park, Sung Kyeong; Lee, Sung-Pyo; Choi, Ehn-Kyoung; Rhee, Man Hee; Kim, Yun-Bae

    2013-12-01

    The effects of nattokinase on the in vitro platelet aggregation and in vivo thrombosis were investigated in comparison with aspirin. Rabbit platelet-rich plasma was incubated with nattokinase and aggregation inducers collagen and thrombin, and the platelet aggregation rate was analyzed. Nattokinase significantly inhibited both the collagen- and thrombin-induced platelet aggregations. Nattokinase also reduced thromboxane B2 formation from collagen-activated platelets in a concentration-dependent manner. Rats were orally administered with nattokinase for 1 week, and their carotid arteries were exposed. Arterial thrombosis was induced by applying 35% FeCl3-soaked filter paper for 10 min, and the blood flow was monitored with a laser Doppler probe. Nattokinase delayed the FeCl3-induced arterial occlusion in a dose-dependent manner, doubling the occlusion time at 160 mg/kg. In addition, a high dose (500 mg/kg) of nattokinase fully prevented the occlusion, as achieved with aspirin (30 mg/kg). The results indicate that nattokinase extracted from fermented soybean inhibit platelet aggregation by blocking thromboxane formation, and thereby delay thrombosis following oxidative arterial wall injury. Therefore, it is suggested that nattokinase could be a good candidate without adverse effects for the improvement of blood flow.

  8. 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 ...

  9. Coupling of aggregation and immunogenicity in biotherapeutics: T- and B-cell immune epitopes may contain aggregation-prone regions.

    Science.gov (United States)

    Kumar, Sandeep; Singh, Satish K; Wang, Xiaoling; Rup, Bonita; Gill, Davinder

    2011-05-01

    Biotherapeutics, including recombinant or plasma-derived human proteins and antibody-based molecules, have emerged as an important class of pharmaceuticals. Aggregation and immunogenicity are among the major bottlenecks during discovery and development of biotherapeutics. Computational tools that can predict aggregation prone regions as well as T- and B-cell immune epitopes from protein sequence and structure have become available recently. Here, we describe a potential coupling between aggregation and immunogenicity: T-cell and B-cell immune epitopes in therapeutic proteins may contain aggregation-prone regions. The details of biological mechanisms behind this observation remain to be understood. However, our observation opens up an exciting potential for rational design of de-immunized novel, as well as follow on biotherapeutics with reduced aggregation propensity.

  10. Optimising cell aggregate expansion in a perfused hollow fibre bioreactor via mathematical modelling.

    KAUST Repository

    Chapman, Lloyd A C; Shipley, Rebecca J; Whiteley, Jonathan P; Ellis, Marianne J; Byrne, Helen M; Waters, Sarah L

    2014-01-01

    , the higher fluid shear stress can lead to cell death. For a given cell type and initial aggregate distribution, the operating parameters that give the most rapid overall growth can be identified from simulations. For example, when aggregates of rat

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

    African Journals Online (AJOL)

    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 donation ...

  12. Aggregation patterns of fetal rat brain cells following exposure to X-irradiation

    International Nuclear Information System (INIS)

    Shoji, R.; Suzuki, K.; Lee, I.P.

    1980-01-01

    In our search for a simplified in vitro test system to assess the teratogenic effects of physical factors, we studied the effects of total maternal body X-irradiation on aggregation patterns of enzymatically isolated fetal rat brain cells and on ultrastructural aggregate changes. The fetal brain cells were derived from day 14 gestation fetuses of pregnant Sprague-Dawley (CD strain) rats exposed to X-irradiation (25 - 200 R) one hour prior to sacrifice. Notable changes in the cell aggregates following X-irradiation included a reduction in cell aggregate size and an increase in number. The frequency of cell aggregates was higher in the treated than in the control group, and the mean diameter of cell aggregates was inversely related to increasing X-irradiation doses. Transmission electron microscopy revealed in isolated cells features of degenerative process which were similar to those found in intact fetal brain lesions caused by maternal X-irradiation. Furthermore, scanning electron microscopy revealed that inhibition of cell aggregation following X-irradiation could probably be attributed to inhibition of membrane filopodia development and a consequent failure of cell aggregates to fuse into a greater cell aggregate mass. These results suggest that the membrane factors which influence cell aggregation may be a useful parameter to assess early effects of X-irradiation-induced brain deformity. Presently, the cell aggregation culture system is being further evaluated as a short term test system for environmental teratogens

  13. Blood-Forming Stem Cell Transplants

    Science.gov (United States)

    ... to Ask about Your Treatment Research Blood-Forming Stem Cell Transplants On This Page What are bone marrow ... Considering becoming a bone marrow or a blood stem cell donor? View this video on YouTube. Follow a ...

  14. Low white blood cell count and cancer

    Science.gov (United States)

    ... gov/ency/patientinstructions/000675.htm Low white blood cell count and cancer To use the sharing features on this page, please enable JavaScript. White blood cells (WBCs) fight infections from bacteria, viruses, fungi, and ...

  15. 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 ...

  16. Transplantation of co-aggregates of Sertoli cells and islet cells into liver without immunosuppression.

    Science.gov (United States)

    Takemoto, Naohiro; Liu, Xibao; Takii, Kento; Teramura, Yuji; Iwata, Hiroo

    2014-02-15

    Transplantation of islets of Langerhans (islets) was used to treat insulin-dependent diabetes mellitus. However, islet grafts must be maintained by administration of immunosuppressive drugs, which can lead to complications in the long term. An approach that avoids immunosuppressive drug use is desirable. Co-aggregates of Sertoli cells and islet cells from BALB/c mice that were prepared by the hanging drop method were transplanted into C57BL/6 mouse liver through the portal vein as in human clinical islet transplantation. The core part of the aggregates contained mainly Sertoli cells, and these cells were surrounded by islet cells. The co-aggregates retained the functions of both Sertoli and islet cells. When 800 co-aggregates were transplanted into seven C57BL/6 mice via the portal vein, six of seven recipient mice demonstrated quasi-normoglycemia for more than 100 days. The hanging drop method is suitable for preparing aggregates of Sertoli and islet cells for transplantation. Notably, transplantation of these allogeneic co-aggregates into mice with chemically induced diabetes via the portal vein resulted in long-term graft survival without systemic immunosuppression.

  17. Clinical Utility of Blood Cell Histogram Interpretation.

    Science.gov (United States)

    Thomas, E T Arun; Bhagya, S; Majeed, Abdul

    2017-09-01

    An automated haematology analyser provides blood cell histograms by plotting the sizes of different blood cells on X-axis and their relative number on Y-axis. Histogram interpretation needs careful analysis of Red Blood Cell (RBC), White Blood Cell (WBC) and platelet distribution curves. Histogram analysis is often a neglected part of the automated haemogram which if interpreted well, has significant potential to provide diagnostically relevant information even before higher level investigations are ordered.

  18. CELLS OVEREXPRESSING HSP27 SHOW ACCELERATED RECOVERY FROM HEAT-INDUCED NUCLEAR-PROTEIN AGGREGATION

    NARCIS (Netherlands)

    KAMPINGA, HH; BRUNSTING, JF; STEGE, GJJ; KONINGS, AWT; LANDRY, J

    1994-01-01

    Protein denaturation/aggregation upon cell exposure to heat shock is a likely cause of cell death. in the nucleus, protein aggregation has often been correlated to inhibition of nuclear located processes and heat-induced cell killing. in Chinese hamster 023 cells made thermotolerant by a prior

  19. A population balance equation model of aggregation dynamics in Taxus suspension cell cultures.

    Science.gov (United States)

    Kolewe, Martin E; Roberts, Susan C; Henson, Michael A

    2012-02-01

    The nature of plant cells to grow as multicellular aggregates in suspension culture has profound effects on bioprocess performance. Recent advances in the measurement of plant cell aggregate size allow for routine process monitoring of this property. We have exploited this capability to develop a conceptual model to describe changes in the aggregate size distribution that are observed over the course of a Taxus cell suspension batch culture. We utilized the population balance equation framework to describe plant cell aggregates as a particulate system, accounting for the relevant phenomenological processes underlying aggregation, such as growth and breakage. We compared model predictions to experimental data to select appropriate kernel functions, and found that larger aggregates had a higher breakage rate, biomass was partitioned asymmetrically following a breakage event, and aggregates grew exponentially. Our model was then validated against several datasets with different initial aggregate size distributions and was able to quantitatively predict changes in total biomass and mean aggregate size, as well as actual size distributions. We proposed a breakage mechanism where a fraction of biomass was lost upon each breakage event, and demonstrated that even though smaller aggregates have been shown to produce more paclitaxel, an optimum breakage rate was predicted for maximum paclitaxel accumulation. We believe this is the first model to use a segregated, corpuscular approach to describe changes in the size distribution of plant cell aggregates, and represents an important first step in the design of rational strategies to control aggregation and optimize process performance. Copyright © 2011 Wiley Periodicals, Inc.

  20. Uptake of carnitine by red blood cells

    International Nuclear Information System (INIS)

    Campa, M.; Borum, P.

    1986-01-01

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

  1. Spaceflight enhances cell aggregation and random budding in Candida albicans.

    Directory of Open Access Journals (Sweden)

    Aurélie Crabbé

    Full Text Available This study presents the first global transcriptional profiling and phenotypic characterization of the major human opportunistic fungal pathogen, Candida albicans, grown in spaceflight conditions. Microarray analysis revealed that C. albicans subjected to short-term spaceflight culture differentially regulated 452 genes compared to synchronous ground controls, which represented 8.3% of the analyzed ORFs. Spaceflight-cultured C. albicans-induced genes involved in cell aggregation (similar to flocculation, which was validated by microscopic and flow cytometry analysis. We also observed enhanced random budding of spaceflight-cultured cells as opposed to bipolar budding patterns for ground samples, in accordance with the gene expression data. Furthermore, genes involved in antifungal agent and stress resistance were differentially regulated in spaceflight, including induction of ABC transporters and members of the major facilitator family, downregulation of ergosterol-encoding genes, and upregulation of genes involved in oxidative stress resistance. Finally, downregulation of genes involved in actin cytoskeleton was observed. Interestingly, the transcriptional regulator Cap1 and over 30% of the Cap1 regulon was differentially expressed in spaceflight-cultured C. albicans. A potential role for Cap1 in the spaceflight response of C. albicans is suggested, as this regulator is involved in random budding, cell aggregation, and oxidative stress resistance; all related to observed spaceflight-associated changes of C. albicans. While culture of C. albicans in microgravity potentiates a global change in gene expression that could induce a virulence-related phenotype, no increased virulence in a murine intraperitoneal (i.p. infection model was observed under the conditions of this study. Collectively, our data represent an important basis for the assessment of the risk that commensal flora could play during human spaceflight missions. Furthermore, since the

  2. 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...

  3. 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.

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

    Science.gov (United States)

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

    2015-07-14

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

  5. 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.

  6. Inhibition of neuronal cell–cell adhesion measured by the microscopic aggregation assay and impedance sensing

    NARCIS (Netherlands)

    Wiertz, Remy; Marani, Enrico; Rutten, Wim

    2010-01-01

    Microscopic aggregation assay and impedance sensing (IS) were used to monitor a change in in vitro neuron–neuron adhesion in response to blocking of cell adhesion molecules. By blocking neuron–neuron adhesion, migration and aggregation of neuronal cells can be inhibited. This leads to better control

  7. Islet-like cell aggregates generated from human adipose tissue derived stem cells ameliorate experimental diabetes in mice.

    Directory of Open Access Journals (Sweden)

    Vikash Chandra

    Full Text Available BACKGROUND: Type 1 Diabetes Mellitus is caused by auto immune destruction of insulin producing beta cells in the pancreas. Currently available treatments include transplantation of isolated islets from donor pancreas to the patient. However, this method is limited by inadequate means of immuno-suppression to prevent islet rejection and importantly, limited supply of islets for transplantation. Autologous adult stem cells are now considered for cell replacement therapy in diabetes as it has the potential to generate neo-islets which are genetically part of the treated individual. Adopting methods of islet encapsulation in immuno-isolatory devices would eliminate the need for immuno-suppressants. METHODOLOGY/PRINCIPAL FINDINGS: In the present study we explore the potential of human adipose tissue derived adult stem cells (h-ASCs to differentiate into functional islet like cell aggregates (ICAs. Our stage specific differentiation protocol permit the conversion of mesodermic h-ASCs to definitive endoderm (Hnf3β, TCF2 and Sox17 and to PDX1, Ngn3, NeuroD, Pax4 positive pancreatic endoderm which further matures in vitro to secrete insulin. These ICAs are shown to produce human C-peptide in a glucose dependent manner exhibiting in-vitro functionality. Transplantation of mature ICAs, packed in immuno-isolatory biocompatible capsules to STZ induced diabetic mice restored near normoglycemia within 3-4 weeks. The detection of human C-peptide, 1155±165 pM in blood serum of experimental mice demonstrate the efficacy of our differentiation approach. CONCLUSIONS: h-ASC is an ideal population of personal stem cells for cell replacement therapy, given that they are abundant, easily available and autologous in origin. Our findings present evidence that h-ASCs could be induced to differentiate into physiologically competent functional islet like cell aggregates, which may provide as a source of alternative islets for cell replacement therapy in type 1 diabetes.

  8. Effect of Blood Contamination on Marginal Adaptation and Surface Microstructure of Mineral Trioxide Aggregate: A SEM Study

    OpenAIRE

    Amin Salem Milani; Saeed Rahimi; Mohammad Froughreyhani; Mahdi Vahid Pakdel

    2013-01-01

    Background and aims. In various clinical situations, mineral trioxide aggregate (MTA) may come into direct contact or even be mixed with blood. The aim of the present study was to evaluate the effect of exposure to blood on marginal adaptation and surface microstructure of MTA. Materials and methods. Thirty extracted human single-rooted teeth were used. Standard root canal treatment was carried out. Root-ends were resected, and retrocavities were prepared. The teeth were randomly ...

  9. Reaction and Aggregation Dynamics of Cell Surface Receptors

    Science.gov (United States)

    Wang, Michelle Dong

    This dissertation is composed of both theoretical and experimental studies of cell surface receptor reaction and aggregation. Project I studies the reaction rate enhancement due to surface diffusion of a bulk dissolved ligand with its membrane embedded target, using numerical calculations. The results show that the reaction rate enhancement is determined by ligand surface adsorption and desorption kinetic rates, surface and bulk diffusion coefficients, and geometry. In particular, we demonstrate that the ligand surface adsorption and desorption kinetic rates, rather than their ratio (the equilibrium constant), are important in rate enhancement. The second and third projects are studies of acetylcholine receptor clusters on cultured rat myotubes using fluorescence techniques after labeling the receptors with tetramethylrhodamine -alpha-bungarotoxin. The second project studies when and where the clusters form by making time-lapse movies. The movies are made from overlay of the pseudocolored total internal reflection fluorescence (TIRF) images of the cluster, and the schlieren images of the cell cultures. These movies are the first movies made using TIRF, and they clearly show the cluster formation from the myoblast fusion, the first appearance of clusters, and the eventual disappearance of clusters. The third project studies the fine structural features of individual clusters observed under TIRF. The features were characterized with six parameters by developing a novel fluorescence technique: spatial fluorescence autocorrelation. These parameters were then used to study the feature variations with age, and with treatments of drugs (oligomycin and carbachol). The results show little variation with age. However, drug treatment induced significant changes in some parameters. These changes were different for oligomycin and carbachol, which indicates that the two drugs may eliminate clusters through different mechanisms.

  10. Nattokinase improves blood flow by inhibiting platelet aggregation and thrombus formation

    OpenAIRE

    Jang, Ja-Young; Kim, Tae-Su; Cai, Jingmei; Kim, Jihyun; Kim, Youngeun; Shin, Kyungha; Kim, Kwang Sei; Park, Sung Kyeong; Lee, Sung-Pyo; Choi, Ehn-Kyoung; Rhee, Man Hee; Kim, Yun-Bae

    2013-01-01

    The effects of nattokinase on the in vitro platelet aggregation and in vivo thrombosis were investigated in comparison with aspirin. Rabbit platelet-rich plasma was incubated with nattokinase and aggregation inducers collagen and thrombin, and the platelet aggregation rate was analyzed. Nattokinase significantly inhibited both the collagen- and thrombin-induced platelet aggregations. Nattokinase also reduced thromboxane B2 formation from collagen-activated platelets in a concentration-depende...

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

    OpenAIRE

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

    2015-01-01

    Oxygen is transported throughout the body by hemoglobin in red blood cells. While the oxygen affinity of blood is well understood and is routinely assessed in patients by pulse oximetry, variability at the single-cell level has not been previously measured. In contrast, single-cell measurements of red blood cell volume and hemoglobin concentration are taken millions of times per day by clinical hematology analyzers and are important factors in determining the health of the hematologic system....

  12. Effects of ethanol on red blood cell rheological behavior.

    Science.gov (United States)

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

    2014-01-01

    Consumption of red wine is associated with a decreased risk of several cardiovascular diseases (e.g., coronary artery disease, stroke), but unfortunately literature reports regarding ethanol's effects on hemorheological parameters are not concordant. In the present study, red blood cell (RBC) deformability was tested via laser ektacytometry (LORCA, 0.3-30 Pa) using two approaches: 1) addition of ethanol to whole blood at 0.25%-2% followed by incubation and testing in ethanol-free LORCA medium; 2) addition of ethanol to the LORCA medium at 0.25%-6% then testing untreated native RBC in these media. The effects of ethanol on deformability for oxidatively stressed RBC were investigated as were changes of RBC aggregation (Myrenne Aggregometer) for cells in autologous plasma or 3% 70 kDa dextran. Significant dose-related increases of RBC deformability were observed at 0.25% (p health benefits of moderate wine consumption require further investigation.

  13. Dielectric spectroscopy platform to measure MCF10A epithelial cell aggregation as a model for spheroidal cell cluster analysis.

    Science.gov (United States)

    Heileman, K L; Tabrizian, M

    2017-05-02

    3-Dimensional cell cultures are more representative of the native environment than traditional cell cultures on flat substrates. As a result, 3-dimensional cell cultures have emerged as a very valuable model environment to study tumorigenesis, organogenesis and tissue regeneration. Many of these models encompass the formation of cell aggregates, which mimic the architecture of tumor and organ tissue. Dielectric impedance spectroscopy is a non-invasive, label free and real time technique, overcoming the drawbacks of established techniques to monitor cell aggregates. Here we introduce a platform to monitor cell aggregation in a 3-dimensional extracellular matrix using dielectric spectroscopy. The MCF10A breast epithelial cell line serves as a model for cell aggregation. The platform maintains sterile conditions during the multi-day assay while allowing continuous dielectric spectroscopy measurements. The platform geometry optimizes dielectric measurements by concentrating cells within the electrode sensing region. The cells show a characteristic dielectric response to aggregation which corroborates with finite element analysis computer simulations. By fitting the experimental dielectric spectra to the Cole-Cole equation, we demonstrated that the dispersion intensity Δε and the characteristic frequency f c are related to cell aggregate growth. In addition, microscopy can be performed directly on the platform providing information about cell position, density and morphology. This platform could yield many applications for studying the electrophysiological activity of cell aggregates.

  14. Fibrillar Structure and Charge Determine the Interaction of Polyglutamine Protein Aggregates with the Cell Surface*

    Science.gov (United States)

    Trevino, R. Sean; Lauckner, Jane E.; Sourigues, Yannick; Pearce, Margaret M.; Bousset, Luc; Melki, Ronald; Kopito, Ron R.

    2012-01-01

    The pathogenesis of most neurodegenerative diseases, including transmissible diseases like prion encephalopathy, inherited disorders like Huntington disease, and sporadic diseases like Alzheimer and Parkinson diseases, is intimately linked to the formation of fibrillar protein aggregates. It is becoming increasingly appreciated that prion-like intercellular transmission of protein aggregates can contribute to the stereotypical spread of disease pathology within the brain, but the mechanisms underlying the binding and uptake of protein aggregates by mammalian cells are largely uninvestigated. We have investigated the properties of polyglutamine (polyQ) aggregates that endow them with the ability to bind to mammalian cells in culture and the properties of the cell surface that facilitate such uptake. Binding and internalization of polyQ aggregates are common features of mammalian cells and depend upon both trypsin-sensitive and trypsin-resistant saturable sites on the cell surface, suggesting the involvement of cell surface proteins in this process. polyQ aggregate binding depends upon the presence of a fibrillar amyloid-like structure and does not depend upon electrostatic interaction of fibrils with the cell surface. Sequences in the huntingtin protein that flank the amyloid-forming polyQ tract also influence the extent to which aggregates are able to bind to cell surfaces. PMID:22753412

  15. Axisymmetric Drop Shape Analysis for Estimating the Surface Tension of Cell Aggregates by Centrifugation

    OpenAIRE

    Kalantarian, Ali; Ninomiya, Hiromasa; Saad, Sameh M.I.; David, Robert; Winklbauer, Rudolf; Neumann, A. Wilhelm

    2009-01-01

    Biological tissues behave in certain respects like liquids. Consequently, the surface tension concept can be used to explain aspects of the in vitro and in vivo behavior of multicellular aggregates. Unfortunately, conventional methods of surface tension measurement cannot be readily applied to small cell aggregates. This difficulty can be overcome by an experimentally straightforward method consisting of centrifugation followed by axisymmetric drop shape analysis (ADSA). Since the aggregates ...

  16. 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.

  17. 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...

  18. Collision Based Blood Cell Distribution of the Blood Flow

    Science.gov (United States)

    Cinar, Yildirim

    2003-11-01

    Introduction: The goal of the study is the determination of the energy transferring process between colliding masses and the application of the results to the distribution of the cell, velocity and kinetic energy in arterial blood flow. Methods: Mathematical methods and models were used to explain the collision between two moving systems, and the distribution of linear momentum, rectilinear velocity, and kinetic energy in a collision. Results: According to decrease of mass of the second system, the velocity and momentum of constant mass of the first system are decreased, and linearly decreasing mass of the second system captures a larger amount of the kinetic energy and the rectilinear velocity of the collision system on a logarithmic scale. Discussion: The cause of concentration of blood cells at the center of blood flow an artery is not explained by Bernoulli principle alone but the kinetic energy and velocity distribution due to collision between the big mass of the arterial wall and the small mass of blood cells must be considered as well.

  19. Intrinsically disordered proteins aggregate at fungal cell-to-cell channels and regulate intercellular connectivity.

    Science.gov (United States)

    Lai, Julian; Koh, Chuan Hock; Tjota, Monika; Pieuchot, Laurent; Raman, Vignesh; Chandrababu, Karthik Balakrishna; Yang, Daiwen; Wong, Limsoon; Jedd, Gregory

    2012-09-25

    Like animals and plants, multicellular fungi possess cell-to-cell channels (septal pores) that allow intercellular communication and transport. Here, using a combination of MS of Woronin body-associated proteins and a bioinformatics approach that identifies related proteins based on composition and character, we identify 17 septal pore-associated (SPA) proteins that localize to the septal pore in rings and pore-centered foci. SPA proteins are not homologous at the primary sequence level but share overall physical properties with intrinsically disordered proteins. Some SPA proteins form aggregates at the septal pore, and in vitro assembly assays suggest aggregation through a nonamyloidal mechanism involving mainly α-helical and disordered structures. SPA loss-of-function phenotypes include excessive septation, septal pore degeneration, and uncontrolled Woronin body activation. Together, our data identify the septal pore as a complex subcellular compartment and focal point for the assembly of unstructured proteins controlling diverse aspects of intercellular connectivity.

  20. Incorporation of Biomaterials in Multicellular Aggregates Modulates Pluripotent Stem Cell Differentiation

    Science.gov (United States)

    Bratt-Leal, Andrés M.; Carpenedo, Richard L.; Ungrin, Mark; Zandstra, Peter W.; McDevitt, Todd C.

    2010-01-01

    Biomaterials are increasingly being used to engineer the biochemical and biophysical properties of the extracellular stem cell microenvironment in order to tailor niche characteristics and direct cell phenotype. To date, stem cell-biomaterial interactions have largely been studied by introducing stem cells into artificial environments, such as 2D cell culture on biomaterial surfaces, encapsulation of cell suspensions within hydrogel materials, or cell seeding on 3D polymeric scaffolds. In this study, microparticles fabricated from different materials, such as agarose, PLGA and gelatin, were stably integrated, in a dose-dependent manner, within aggregates of pluripotent stem cells (PSCs) prior to differentiation as a means to directly examine stem cell-biomaterial interactions in 3D. Interestingly, the presence of the materials within the stem cell aggregates differentially modulated the gene and protein expression patterns of several differentiation markers without adversely affecting cell viability. Microparticle incorporation within 3D stem cell aggregates can control the spatial presentation of extracellular environmental cues (i.e. soluble factors, extracellular matrix and intercellular adhesion molecules) as a means to direct the differentiation of stem cells for tissue engineering and regenerative medicine applications. In addition, these results suggest that the physical presence of microparticles within stem cell aggregates does not compromise PSC differentiation, but in fact the choice of biomaterials can impact the propensity of stem cells to adopt particular differentiated cell phenotypes. PMID:20864164

  1. Effect of dextran-induced changes in refractive index and aggregation on optical properties of whole blood

    International Nuclear Information System (INIS)

    Xu Xiangqun; Wang, Ruikang K; Elder, James B; Tuchin, Valery V

    2003-01-01

    The purpose of the present study is to investigate systematically the mechanisms of alterations in the optical properties of whole blood immersed in the biocompatible agent dextran, and to define the optimal concentration of dextrans required for blood optical clearing in order to enhance the capability of light penetration depth for optical imaging applications. In the experiments, dextrans with different molecular weights and various concentrations were employed and investigated by the use of the optical coherence tomography technique. Changes in light attenuation, refractive index and aggregation properties of blood immersed in dextrans were studied. It was concluded from the results that the mechanisms for blood optical clearing are characteristic of the types of dextrans employed, their concentrations and the application stages. Among the substances applied, Dx500 at a concentration at 0.5 g dl -1 gives the best result in improving light penetration depth through the blood. The increase of light transmission at the beginning of the addition of dextrans is mainly attributed to refractive index matching between the scattering centres and the ground matter. Thereafter, the transmission change is probably due to a dextran-induced aggregation-disaggregation effect. Overall, light scattering in the blood could be effectively reduced by the application of dextrans. It represents a promising approach to increasing the imaging depth for in vivo optical imaging of biological tissue, for example optical coherence tomography

  2. Development of long-term primary cell aggregates from Mediterranean octocorals.

    Science.gov (United States)

    Huete-Stauffer, Carla; Valisano, Laura; Gaino, Elda; Vezzulli, Luigi; Cerrano, Carlo

    2015-09-01

    In lower metazoans, the aggregative properties of dissociated cells leading to in vitro stable multicellular aggregates have furnished a remarkable experimental material to carry out investigations in various research fields. One of the main expectations is to find good models for the study in vitro of the first steps of biomineralization processes. In this study, we examined five common Mediterranean gorgonians (Paramuricea clavata, Corallium rubrum, Eunicella singularis, Eunicella cavolinii, and Eunicella verrucosa) using mechanical cell aggregate production techniques. In particular, we investigated the conditions of aggregate formation, their number and survival in experimental conditions, the DNA synthesizing activity using 5'-bromo-2'-deoxyuridine (BrdU) tests, and the response to calcein addition and observed the secretion of newly formed sclerites. The BrdU tests showed that cell proliferation depends on the size of aggregates and on the presence/absence of symbiotic zooxanthellae. With epifluorescent and confocal imaging from calcein addition assays, we observed the presence of calcium ions within cells, a possible clue for prediction of sclerite formation or calcium deposition. The species-specific efficiency in production of cell aggregates is correlated to the size of polyps, showing that the higher density of polyps and their diameter correspond to higher production of cell aggregates. Regarding the long-term maintenance, we obtained the best results from E. singularis, which formed multicellular aggregates of 0.245 mm ± 0.086 mm in size and maintained symbiotic association with zooxanthellae throughout the experimental run. Formation of sclerites within aggregates opens a wide field of investigation on biomineralization, since de novo sclerites were observed around 30 d after the beginning of the experiment.

  3. 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)

  4. Measurement of whole blood of different mammalian species in the oscillating shear field: influence of erythrocyte aggregation

    International Nuclear Information System (INIS)

    Windberger, U; Pöschl, Ch; Peters, S; Huber, J; Van den Hoven, R

    2017-01-01

    This is the first systematic analysis of mammalian blood of species with a high (horse), medium (man), and low (sheep) erythrocyte (RBC) aggregability by small amplitude oscillation technique. Amplitude and frequency sweep tests (linear viscoelastic mode) were performed with blood from healthy adult volunteers, horses, and sheep in CSS-mode. Blood samples were hematocrit (HCT) adjusted (40%, 50%, 60%) and tested at 7°C, 22°C, and 37°C. Generally, storage modulus (G´) increased with HCT and decreased with temperature in each species, but the gradient of this increase was species-specific. The lower dependency of G´ on the equine HCT value could be a benefit during physical performance when high numbers of RBCs are released from the spleen. In sheep, an HCT-threshold had to be overcome before the desired quasi-static condition of the blood sample could be achieved, suggesting that the contact between RBCs, and between RBCs and plasma molecules must be very low. The frequencies for tests under linear viscoelastic condition were in a narrow range around the physiologic heart rate of the species. In horse, time-dependent influences concurred at frequencies lower than 3 rad.s -1 probably due to sedimentation of RBC aggregates. In conclusion, blood is a fragile suspension that shows its best stability around the resting heart rate of the species. (paper)

  5. Measurement of whole blood of different mammalian species in the oscillating shear field: influence of erythrocyte aggregation

    Science.gov (United States)

    Windberger, U.; Pöschl, Ch; Peters, S.; Huber, J.; van den Hoven, R.

    2017-01-01

    This is the first systematic analysis of mammalian blood of species with a high (horse), medium (man), and low (sheep) erythrocyte (RBC) aggregability by small amplitude oscillation technique. Amplitude and frequency sweep tests (linear viscoelastic mode) were performed with blood from healthy adult volunteers, horses, and sheep in CSS-mode. Blood samples were hematocrit (HCT) adjusted (40%, 50%, 60%) and tested at 7°C, 22°C, and 37°C. Generally, storage modulus (G´) increased with HCT and decreased with temperature in each species, but the gradient of this increase was species-specific. The lower dependency of G´ on the equine HCT value could be a benefit during physical performance when high numbers of RBCs are released from the spleen. In sheep, an HCT-threshold had to be overcome before the desired quasi-static condition of the blood sample could be achieved, suggesting that the contact between RBCs, and between RBCs and plasma molecules must be very low. The frequencies for tests under linear viscoelastic condition were in a narrow range around the physiologic heart rate of the species. In horse, time-dependent influences concurred at frequencies lower than 3 rad.s-1probably due to sedimentation of RBC aggregates. In conclusion, blood is a fragile suspension that shows its best stability around the resting heart rate of the species.

  6. 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,

  7. 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.)

  8. Modulating and modeling aggregation of cell-seeded microcarriers in stirred culture system for macrotissue engineering.

    Science.gov (United States)

    Mei, Yang; Luo, Houyong; Tang, Qiang; Ye, Zhaoyang; Zhou, Yan; Tan, Wen-Song

    2010-11-01

    A recently developed protocol, "microtissue assembly" holds great promise to address the issue of limited mass transfer within engineered large tissue replacements (macrotissues), wherein small "building blocks" (microtissues) are prepared and then assembled into macrotissues. Previous studies suggested that aggregation behavior of microcarrier-based microtissues were very important for macrotissue engineering. However, a systematic study on the aggregation behavior of microtissues is still missing. In this study, to examine the aggregation behavior of microtissues, effects of key operation parameters in dynamic culture including cell seeding density, microcarrier concentration, L-ascorbic acid 2-phosphate (V(c)) and agitating speed were investigated. The aggregation process could be divided into three phases (i.e., lag, growth and stable). Aggregation efficiency (S) was found to be modulated by cell seeding density, microcarrier concentration, addition of V(c) and agitating speed. A mathematical model correlating the operation parameters with S at different phases of aggregation was developed and experimentally proved to be able to predict S with varied operation parameters. In the end, a cylindrical macrotissue (diameter × height: 2.0 cm × 0.8 cm) with fairly good integrity and cellularity and uniform cell distribution was successfully engineered through perfusion assembling microtissues with controlled S under selected culture conditions. Our study showed that aggregation of microtissues could be precisely modulated, which would definitely facilitate engineering macrotissues with high quality. Copyright © 2010 Elsevier B.V. All rights reserved.

  9. Blood banking-induced alteration of red blood cell oxygen release ability.

    Science.gov (United States)

    Li, Yaojin; Xiong, Yanlian; Wang, Ruofeng; Tang, Fuzhou; Wang, Xiang

    2016-05-01

    Current blood banking procedures may not fully preserve red blood cell (RBC) function during storage, contributing to the decrease of RBC oxygen release ability. This study was undertaken to evaluate the impact of routine cold storage on RBC oxygen release ability. RBC units were collected from healthy donors and each unit was split into two parts (whole blood and suspended RBC) to exclude possible donor variability. Oxygen dissociation measurements were performed on blood units stored at 4 °C during a 5-week period. 2,3-diphosphoglycerate levels and fluorescent micrographs of erythrocyte band 3 were also analysed. P50 and oxygen release capacity decreased rapidly during the first 3 weeks, and then did not change significantly. In contrast, the kinetic properties (PO2-t curve and T*50) of oxygen release changed slowly during the first 3 weeks of storage, but then decreased significantly in the last 2 weeks. 2,3-diphosphoglycerate decreased quickly during the first 3 weeks of storage to almost undetectable levels. Band 3 aggregated significantly during the last 2 weeks of storage. RBC oxygen release ability appears to be sensitive to routine cold storage. The thermodynamic characteristics of RBC oxygen release ability changed mainly in the first 3 weeks of storage, due to the decrease of 2,3-diphosphoglycerate, whereas the kinetic characteristics of RBC oxygen release ability decreased significantly at the end of storage, probably affected by alterations of band 3.

  10. Optical tweezers for measuring the interaction of the two single red blood cells in flow condition

    Science.gov (United States)

    Lee, Kisung; Muravyov, Alexei; Semenov, Alexei; Wagner, Christian; Priezzhev, Alexander

    2017-03-01

    Aggregation of red blood cells (RBCs) is an intrinsic property of blood, which has direct effect on the blood viscosity and therefore affects overall the blood circulation throughout the body. It is attracting interest for the research in both fundamental science and clinical application. Despite of the intensive research, the aggregation mechanism is remaining not fully clear. Recent advances in methods allowed measuring the interaction between single RBCs in a well-defined configuration leading the better understanding of the mechanism of the process. However the most of the studies were made on the static cells. Thus, the measurements in flow mimicking conditions are missing. In this work, we aim to study the interaction of two RBCs in the flow conditions. We demonstrate the characterization of the cells interaction strength (or flow tolerance) by measuring the flow velocity to be applied to separate two aggregated cells trapped by double channel optical tweezers in a desired configuration. The age-separated cells were used for this study. The obtained values for the minimum flow velocities needed to separate the two cells were found to be 78.9 +/- 6.1 μm/s and 110 +/- 13 μm/s for old and young cells respectively. The data obtained is in agreement with the observations reported by other authors. The significance of our results is in ability for obtaining a comprehensible and absolute physical value characterizing the cells interaction in flow conditions (not like the Aggregation Index measured in whole blood suspensions by other techniques, which is some abstract parameter)

  11. 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

  12. Aggregate formation and suspension culture of human pluripotent stem cells and differentiated progeny.

    Science.gov (United States)

    Hookway, Tracy A; Butts, Jessica C; Lee, Emily; Tang, Hengli; McDevitt, Todd C

    2016-05-15

    Culture of human pluripotent stem cells (hPSC) as in vitro multicellular aggregates has been increasingly used as a method to model early embryonic development. Three-dimensional assemblies of hPSCs facilitate interactions between cells and their microenvironment to promote morphogenesis, analogous to the multicellular organization that accompanies embryogenesis. In this paper, we describe a method for reproducibly generating and maintaining populations of homogeneous three-dimensional hPSC aggregates using forced aggregation and rotary orbital suspension culture. We propose solutions to several challenges associated with the consistent formation and extended culture of cell spheroids generated from hPSCs and their differentiated progeny. Further, we provide examples to demonstrate how aggregation can be used as a tool to select specific subpopulations of cells to create homotypic spheroids, or as a means to introduce multiple cell types to create heterotypic tissue constructs. Finally, we demonstrate that the aggregation and rotary suspension method can be used to support culture and maintenance of hPSC-derived cell populations representing each of the three germ layers, underscoring the utility of this platform for culturing many different cell types. Copyright © 2015 Elsevier Inc. All rights reserved.

  13. Conformational targeting of fibrillar polyglutamine proteins in live cells escalates aggregation and cytotoxicity.

    Directory of Open Access Journals (Sweden)

    Erik Kvam

    2009-05-01

    Full Text Available Misfolding- and aggregation-prone proteins underlying Parkinson's, Huntington's and Machado-Joseph diseases, namely alpha-synuclein, huntingtin, and ataxin-3 respectively, adopt numerous intracellular conformations during pathogenesis, including globular intermediates and insoluble amyloid-like fibrils. Such conformational diversity has complicated research into amyloid-associated intracellular dysfunction and neurodegeneration. To this end, recombinant single-chain Fv antibodies (scFvs are compelling molecular tools that can be selected against specific protein conformations, and expressed inside cells as intrabodies, for investigative and therapeutic purposes.Using atomic force microscopy (AFM and live-cell fluorescence microscopy, we report that a human scFv selected against the fibrillar form of alpha-synuclein targets isomorphic conformations of misfolded polyglutamine proteins. When expressed in the cytoplasm of striatal cells, this conformation-specific intrabody co-localizes with intracellular aggregates of misfolded ataxin-3 and a pathological fragment of huntingtin, and enhances the aggregation propensity of both disease-linked polyglutamine proteins. Using this intrabody as a tool for modulating the kinetics of amyloidogenesis, we show that escalating aggregate formation of a pathologic huntingtin fragment is not cytoprotective in striatal cells, but rather heightens oxidative stress and cell death as detected by flow cytometry. Instead, cellular protection is achieved by suppressing aggregation using a previously described intrabody that binds to the amyloidogenic N-terminus of huntingtin. Analogous cytotoxic results are observed following conformational targeting of normal or polyglutamine-expanded human ataxin-3, which partially aggregate through non-polyglutamine domains.These findings validate that the rate of aggregation modulates polyglutamine-mediated intracellular dysfunction, and caution that molecules designed to

  14. 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.

  15. 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

  16. Axisymmetric drop shape analysis for estimating the surface tension of cell aggregates by centrifugation.

    Science.gov (United States)

    Kalantarian, Ali; Ninomiya, Hiromasa; Saad, Sameh M I; David, Robert; Winklbauer, Rudolf; Neumann, A Wilhelm

    2009-02-18

    Biological tissues behave in certain respects like liquids. Consequently, the surface tension concept can be used to explain aspects of the in vitro and in vivo behavior of multicellular aggregates. Unfortunately, conventional methods of surface tension measurement cannot be readily applied to small cell aggregates. This difficulty can be overcome by an experimentally straightforward method consisting of centrifugation followed by axisymmetric drop shape analysis (ADSA). Since the aggregates typically show roughness, standard ADSA cannot be applied and we introduce a novel numerical method called ADSA-IP (ADSA for imperfect profile) for this purpose. To examine the new methodology, embryonic tissues from the gastrula of the frog, Xenopus laevis, deformed in the centrifuge are used. It is confirmed that surface tension measurements are independent of centrifugal force and aggregate size. Surface tension is measured for ectodermal cells in four sample batches, and varies between 1.1 and 7.7 mJ/m2. Surface tension is also measured for aggregates of cells expressing cytoplasmically truncated EP/C-cadherin, and is approximately half as large. In parallel, such aggregates show a reduction in convergent extension-driven elongation after activin treatment, reflecting diminished intercellular cohesion.

  17. 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 ...

  18. 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

  19. Jamming and liquidity in 3D cancer cell aggregates

    Science.gov (United States)

    Oswald, Linda; Grosser, Steffen; Lippoldt, Jürgen; Pawlizak, Steve; Fritsch, Anatol; KäS, Josef A.

    Traditionally, tissues are treated as simple liquids, which holds for example for embryonic tissue. However, recent experiments have shown that this picture is insufficient for other tissue types, suggesting possible transitions to solid-like behavior induced by cellular jamming. The coarse-grained self-propelled Voronoi (SPV) model predicts such a transition depending on cell shape which is thought to arise from an interplay of cell-cell adhesion and cortical tension. We observe non-liquid behavior in 3D breast cancer spheroids of varying metastatic potential and correlate single cell shapes, single cell dynamics and collective dynamic behavior of fusion and segregation experiments via the SPV model.

  20. Complement Activation Induces Neutrophil Adhesion and Neutrophil-Platelet Aggregate Formation on Vascular Endothelial Cells

    Directory of Open Access Journals (Sweden)

    Magdalena Riedl

    2017-01-01

    Discussion: Therefore, our findings of (i neutrophils adhering to complement-activated endothelial cells, (ii the formation of neutrophil-platelet aggregates on endothelial cells, and (iii the ability of aHUS serum to induce similar effects identify a possible role for neutrophils in aHUS manifestation.

  1. Use of magnetic forces to promote stem cell aggregation during differentiation, and cartilage tissue modeling.

    Science.gov (United States)

    Fayol, D; Frasca, G; Le Visage, C; Gazeau, F; Luciani, N; Wilhelm, C

    2013-05-14

    Magnetic forces induce cell condensation necessary for stem cell differentiation into cartilage and elicit the formation of a tissue-like structure: Magnetically driven fusion of aggregates assembled by micromagnets results in the formation of a continuous tissue layer containing abundant cartilage matrix. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Phytoplankton aggregate formation: observations of patterns and mechanisms of cell sticking and the significance of exopolymeric material

    DEFF Research Database (Denmark)

    Kiørboe, Thomas; Hansen, Jorgen L. S.

    1993-01-01

    are sticky in themselves, and coagulation depends on cell-cell sticking and does not involve mucus. Aggregates are composed solely of cells. Cells of the diatom Chaetoceros affinis, on the other hand, are not in themselves sticky. Transparent exopolymeric particles (TEP), produced by the diatom, cause...... the cells to aggregate and coagulation depends on TEP-cell rather than cell-cell sticking. Aggregates are formed of a mixture of mucus and cells. We found several species of diatoms and one flagellate species to produce copious amounts of TEP. TEP from some species (e.g. Coscinodiscus sp.) is sticky and may...

  3. Color stability, radiopacity, and chemical characteristics of white mineral trioxide aggregate associated with 2 different vehicles in contact with blood.

    Science.gov (United States)

    Guimarães, Bruno Martini; Tartari, Talita; Marciano, Marina Angélica; Vivan, Rodrigo Ricci; Mondeli, Rafael Francisco Lia; Camilleri, Josette; Duarte, Marco Antonio Hungaro

    2015-06-01

    Discoloration of mineral trioxide aggregate (MTA) can be exacerbated by the interaction of the cement with body fluids such as blood. This study aimed to analyze the color alteration, chemical characteristics, and radiopacity of MTA manipulated with 2 different vehicles after immersion in blood or distilled water (DW). MTA mixed with 100% DW or 80% DW/20% propylene glycol (PG) as vehicles were placed into rubber rings and incubated at 37°C and 100% relative humidity until set. Color assessment and scanning electron microscopy/energy-dispersive spectroscopy analysis were performed after setting and repeated after 7, 15, and 30 days after immersion in blood and DW. Statistical analysis for color alteration and radiopacity was performed using nonparametric Kruskal-Wallis and Dunn tests (P vehicle, significantly lower color alterations were observed for all time periods compared with 100% DW when immersed in blood (P media because of loss of bismuth. A decrease in radiopacity was observed over time in all groups, with a statistically significant difference after 30 days for groups DW immersed in blood and 80% DW/20% immersed in both media (P vehicle for MTA results in a lower color alteration when in contact with blood. Copyright © 2015 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  4. Effect of Blood Contamination on Marginal Adaptation and Surface Microstructure of Mineral Trioxide Aggregate: A SEM Study

    Directory of Open Access Journals (Sweden)

    Amin Salem Milani

    2013-08-01

    Full Text Available Background and aims. In various clinical situations, mineral trioxide aggregate (MTA may come into direct contact or even be mixed with blood. The aim of the present study was to evaluate the effect of exposure to blood on marginal adaptation and surface microstructure of MTA. Materials and methods. Thirty extracted human single-rooted teeth were used. Standard root canal treatment was carried out. Root-ends were resected, and retrocavities were prepared. The teeth were randomly divided into two groups (n = 15: in group 1, the internal surface of the cavities was coated with fresh blood. Then, the cavities were filled with MTA. The roots were immersed in molds containing fresh blood. In group 2, the aforementioned procedures were performed except that synthetic tissue fluid (STF was used instead of blood. To assess the marginal adaptation, “gap perimeter” and “maximum gap width” were measured under scanning electron microscope. The surface microstructure was also examined. Independent samples t-test and Mann-Whitney U test were used to analyze the data. Results. Maximum gap width and gap perimeter in the blood-exposed group were significantly larger than those in the STF-exposed group (p < 0.01. In the blood-exposed group, the crystals tended to be more rounded and less angular compared with the STF-exposed group, and there was a general lack of needle-like crystals. Conclusion. Exposure to blood during setting has a negative effect on marginal adaptation of MTA, and blood-exposed MTA has a different surface microstructure compared to STF-exposed MTA.

  5. Effect of Blood Contamination on Marginal Adaptation and Surface Microstructure of Mineral Trioxide Aggregate: A SEM Study.

    Science.gov (United States)

    Salem Milani, Amin; Rahimi, Saeed; Froughreyhani, Mohammad; Vahid Pakdel, Mahdi

    2013-01-01

    In various clinical situations, mineral trioxide aggregate (MTA) may come into direct contact or even be mixed with blood. The aim of the present study was to evaluate the effect of exposure to blood on marginal adaptation and surface microstructure of MTA. Thirty extracted human single-rooted teeth were used. Standard root canal treatment was carried out. Root-ends were resected, and retrocavities were prepared. The teeth were randomly divided into two groups (n = 15): in group 1, the internal surface of the cavities was coated with fresh blood. Then, the cavities were filled with MTA. The roots were immersed in molds containing fresh blood. In group 2, the aforementioned procedures were performed except that synthetic tissue fluid (STF) was used instead of blood. To assess the marginal adaptation, "gap perimeter" and "maximum gap width" were measured under scanning electron microscope. The surface microstructure was also examined. Independent samples t-test and Mann-Whitney U test were used to analyze the data. Maximum gap width and gap perimeter in the blood-exposed group were significantly larger than those in the STF-exposed group (p < 0.01). In the blood-exposed group, the crystals tended to be more rounded and less angular compared with the STF-exposed group, and there was a general lack of needle-like crystals. Exposure to blood during setting has a negative effect on marginal adaptation of MTA, and blood-exposed MTA has a different surface microstructure compared to STF-exposed MTA.

  6. Familial aggregation in blood pressure and body composition in portuguese nuclear families

    Directory of Open Access Journals (Sweden)

    Rogério César Fermino

    2008-06-01

    Full Text Available The aims of this study were (1 to verify the indirect presence of vertical transmission of genetic factors between parents and children in blood pressure (BP and body composition (BC, and (2 identify the infl uence of genetic factors in the variability of BP and BC. Sample size comprises 367 subjects (164 parents: 41±4.6 years old and 203 children of 13.2±3 years old from 107 nuclear families participating in the project “FAMÍLIAS ACTIVAS”; they proceed from different regions of North of Portugal (36 from Vouzela, 36 from Esposende, 25 from Vila Nova de Paiva and 10 from Vila Nova de Famalicão. BP was measured with an automatic digital device, Omron® model M6 (HEM-7001-E. BC phenotypes were assessed with a bioelectric impedance device from Tanita® model BC-418 (Tanita Corp., Tokyo, Japan. PEDSTATS was used to verify the structure of each family and to analyze the generic behavior of the variables in family members. FCOR and ASSOC modules, from Genetic Epidemiology S.A.G.E. 5.3 software, were use to calculate correlations (r and the heritability (h2 of different phenotypes. Signifi cant level was set at 0.05. Main results evidenced an important familial aggregation between family members for systolic BP (SBP (0.01≤ r ≤0.35, and diastolic BP (DBP (0.24≤ r ≤0.50 the same occurred for BC phenotypes (-0.15≤ r ≤0.65. Genetic factors contributed to 43% of the SBP and 49% of DBP variation; the same occurred for BC phenotypes ranging from 35 to 46% of the total variation. The conclusions were that (1 a strong familial aggregation exists in the BP and the BC in this sample of portuguese nuclear families and that (2 genetic factors play important role in these phenotypes.ResumoO objetivo deste estudo foi (1 verifi car a presença indireta de transmissão vertical de fatores genéticos entre progenitores e descendentes na pressão arterial (PA e na composição corporal (CC, e (2 estimar a contribuição dos fatores genéticos que s

  7. Exploring new biological functions of amyloids: bacteria cell agglutination mediated by host protein aggregation.

    Directory of Open Access Journals (Sweden)

    Marc Torrent

    Full Text Available Antimicrobial proteins and peptides (AMPs are important effectors of the innate immune system that play a vital role in the prevention of infections. Recent advances have highlighted the similarity between AMPs and amyloid proteins. Using the Eosinophil Cationic Protein as a model, we have rationalized the structure-activity relationships between amyloid aggregation and antimicrobial activity. Our results show how protein aggregation can induce bacteria agglutination and cell death. Using confocal and total internal reflection fluorescence microscopy we have tracked the formation in situ of protein amyloid-like aggregates at the bacteria surface and on membrane models. In both cases, fibrillar aggregates able to bind to amyloid diagnostic dyes were detected. Additionally, a single point mutation (Ile13 to Ala can suppress the protein amyloid behavior, abolishing the agglutinating activity and impairing the antimicrobial action. The mutant is also defective in triggering both leakage and lipid vesicle aggregation. We conclude that ECP aggregation at the bacterial surface is essential for its cytotoxicity. Hence, we propose here a new prospective biological function for amyloid-like aggregates with potential biological relevance.

  8. 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.

  9. Red blood cell alloimmunization among sickle cell Kuwaiti Arab patients who received red blood cell transfusion.

    Science.gov (United States)

    Ameen, Reem; Al Shemmari, Salem; Al-Bashir, Abdulaziz

    2009-08-01

    Sickle cell disease (SCD) is common in the Arabian Gulf region. Most cases require a red blood cell (RBC) transfusion, increasing the potential for RBC alloantibody development. The incidence of RBC alloimmunization among Kuwaiti Arab SCD patients is not yet known. This study retrospectively assessed the effect of using two different matching protocols on the incidence of alloimmunization among multiply transfused Kuwaiti Arab SCD patients. A total of 233 Kuwaiti Arab SCD patients were divided into two groups: Group 1 (n = 110) received RBC transfusion through standard ABO- and D-matched nonleukoreduced blood; Group 2 (n = 123) received RBCs matched for ABO, Rh, and K1 poststorage-leukoreduced blood. Multivariate analysis was performed on the factors associated with RBC alloimmunization and antibody specificity. Sixty-five percent of patients in Group 1 developed clinically significant RBC alloantibody with an increased prevalence in females; in patients in Group 2, 23.6% developed RBC alloantibodies (p = 0.01). In Group 1, 72 patients (65.5%) had alloantibodies directed against Rh and Kell systems (p = 0.01). Multivariate analysis further confirmed the results, showing that blood transfusion type and sex have significant effects on the rate of alloimmunizations. This study confirms the importance of selecting RBCs matched for Rh and Kell to reduce the risk of alloimmunizations among Kuwaiti Arab SCD patients.

  10. MODELS FOR MOUSE CHIMERA PRODUCTION: AGGREGATION OF ES CELLS WITH CLEAVAGE STAGE EMBRYOS

    Directory of Open Access Journals (Sweden)

    STANCA CLAUDIA

    2007-01-01

    Full Text Available In a mutant ES cells↔ wild-type embryo chimera, ES cells behave more like epiblastcells. They can contribute to the primitive ectoderm layers, which give rise to all theembryonic tissues and some extraembryonic tissues (Beddington and Robertson,1989, but not to trophectoderm or primitive endoderm. Using transgenic ES celllines, aggregated with cleavage stage host embryo, ES cells can integrate randomlyin the embryo proper. If they will be take part in the formation of ICM (inner cellmass, it will be possible to obtain germline chimera animals. To generate ES cells↔ cleavage stage host embryo chimeras, we used (CD-1 mice as donors of hostembryos as well as recipients of manipulated embryos. For chimera production, weused fluorescent-labeled ES cell line (CD1/EGFP, because in this case we canfollow the fate of ES cells during the embryonic development. We produced thechimers using “aggregation chimera technique”. 8 cells stage zona pellucida free,mouse embryos were aggregated in an aggregation plates, with a clump of ES cells(10 – 15 cells. The chimera embryos were cultivated for 24 hours in the incubator(at 37 °C, 5% CO2 in air. The chimera blastocysts resulted after cultivation, weretransferred to the uterus of the 2.5-dpc pseudo pregnant females.

  11. MODELS FOR MOUSE CHIMERA PRODUCTION: AGGREGATION OF ES CELLS WITH CLEAVAGE STAGE EMBRYOS

    Directory of Open Access Journals (Sweden)

    CLAUDIA STANCA

    2007-05-01

    Full Text Available In a mutant ES cells↔ wild-type embryo chimera, ES cells behave more like epiblastcells. They can contribute to the primitive ectoderm layers, which give rise to all theembryonic tissues and some extraembryonic tissues (Beddington and Robertson,1989, but not to trophectoderm or primitive endoderm. Using transgenic ES celllines, aggregated with cleavage stage host embryo, ES cells can integrate randomlyin the embryo proper. If they will be take part in the formation of ICM (inner cellmass, it will be possible to obtain germline chimera animals. To generate ES cells↔ cleavage stage host embryo chimeras, we used (CD-1 mice as donors of hostembryos as well as recipients of manipulated embryos. For chimera production, weused fluorescent-labeled ES cell line (CD1/EGFP, because in this case we canfollow the fate of ES cells during the embryonic development. We produced thechimers using “aggregation chimera technique”. 8 cells stage zona pellucida free,mouse embryos were aggregated in an aggregation plates, with a clump of ES cells(10 – 15 cells. The chimera embryos were cultivated for 24 hours in the incubator(at 37 °C, 5% CO2 in air. The chimera blastocysts resulted after cultivation, weretransferred to the uterus of the 2.5-dpc pseudo pregnant females.

  12. A 31-residue peptide induces aggregation of tau's microtubule-binding region in cells

    Science.gov (United States)

    Stöhr, Jan; Wu, Haifan; Nick, Mimi; Wu, Yibing; Bhate, Manasi; Condello, Carlo; Johnson, Noah; Rodgers, Jeffrey; Lemmin, Thomas; Acharya, Srabasti; Becker, Julia; Robinson, Kathleen; Kelly, Mark J. S.; Gai, Feng; Stubbs, Gerald; Prusiner, Stanley B.; Degrado, William F.

    2017-09-01

    The self-propagation of misfolded conformations of tau underlies neurodegenerative diseases, including Alzheimer's. There is considerable interest in discovering the minimal sequence and active conformational nucleus that defines this self-propagating event. The microtubule-binding region, spanning residues 244-372, reproduces much of the aggregation behaviour of tau in cells and animal models. Further dissection of the amyloid-forming region to a hexapeptide from the third microtubule-binding repeat resulted in a peptide that rapidly forms fibrils in vitro. We show that this peptide lacks the ability to seed aggregation of tau244-372 in cells. However, as the hexapeptide is gradually extended to 31 residues, the peptides aggregate more slowly and gain potent activity to induce aggregation of tau244-372 in cells. X-ray fibre diffraction, hydrogen-deuterium exchange and solid-state NMR studies map the beta-forming region to a 25-residue sequence. Thus, the nucleus for self-propagating aggregation of tau244-372 in cells is packaged in a remarkably small peptide.

  13. Quantification of the aggregation of magnetic nanoparticles with different polymeric coatings in cell culture medium

    International Nuclear Information System (INIS)

    Eberbeck, D; Zirpel, P; Trahms, L; Kettering, M; Hilger, I; Bergemann, C

    2010-01-01

    The knowledge of the physico-chemical characteristics of magnetic nanoparticles (MNPs) is essential to enhance the efficacy of MNP-based therapeutic treatments (e.g. magnetic heating, magnetic drug targeting). According to the literature, the MNP uptake by cells may depend on the coating of MNPs, the surrounding medium as well as on the aggregation behaviour of the MNPs. Therefore, in this study, the aggregation behaviour of MNPs in various media was investigated. MNPs with different coatings were suspended in cell culture medium (CCM) containing fetal calf serum (FCS) and the distribution of the hydrodynamic sizes was measured by magnetorelaxometry (MRX). FCS as well as bovine serum albumin (BSA) buffer (phosphate buffered saline with 0.1% bovine serum albumin) may induce MNP aggregation. Its strength depends crucially on the type of coating. The degree of aggregation in CCM depends on its FCS content showing a clear, local maximum at FCS concentrations, where the IgG concentration (part of FCS) is of the order of the MNP number concentration. Thus, we attribute the observed aggregation behaviour to the mechanism of agglutination of MNPs by serum compartments as for example IgG. No aggregation was induced for MNPs coated with dextran, polyarabic acid or sodium phosphate, respectively, which were colloidally stable in CCM.

  14. 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

  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. 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

  20. Banking on cord blood stem cells.

    Science.gov (United States)

    Sullivan, Michael J

    2008-07-01

    Umbilical cord blood gifted to non-profit public cord blood banks is now routinely used as an alternative source of haematopoietic stem cells for allogeneic transplantation for children and adults with cancer, bone marrow failure syndromes, haemoglobinopathies and many genetic metabolic disorders. Because of the success and outcomes of public cord banking, many companies now provide private cord banking services. However, in the absence of any published transplant evidence to support autologous and non-directed family banking, commercial cord banks currently offer a superfluous service.

  1. CAG Expansions Are Genetically Stable and Form Nontoxic Aggregates in Cells Lacking Endogenous Polyglutamine Proteins

    Directory of Open Access Journals (Sweden)

    Ashley A. Zurawel

    2016-09-01

    Full Text Available Proteins containing polyglutamine (polyQ regions are found in almost all eukaryotes, albeit with various frequencies. In humans, proteins such as huntingtin (Htt with abnormally expanded polyQ regions cause neurodegenerative diseases such as Huntington’s disease (HD. To study how the presence of endogenous polyQ aggregation modulates polyQ aggregation and toxicity, we expressed polyQ expanded Htt fragments (polyQ Htt in Schizosaccharomyces pombe. In stark contrast to other unicellular fungi, such as Saccharomyces cerevisiae, S. pombe is uniquely devoid of proteins with more than 10 Q repeats. We found that polyQ Htt forms aggregates within S. pombe cells only with exceedingly long polyQ expansions. Surprisingly, despite the presence of polyQ Htt aggregates in both the cytoplasm and nucleus, no significant growth defect was observed in S. pombe cells. Further, PCR analysis showed that the repetitive polyQ-encoding DNA region remained constant following transformation and after multiple divisions in S. pombe, in contrast to the genetic instability of polyQ DNA sequences in other organisms. These results demonstrate that cells with a low content of polyQ or other aggregation-prone proteins can show a striking resilience with respect to polyQ toxicity and that genetic instability of repetitive DNA sequences may have played an important role in the evolutionary emergence and exclusion of polyQ expansion proteins in different organisms.

  2. Platelet aggregation following trauma

    DEFF Research Database (Denmark)

    Windeløv, Nis A; Sørensen, Anne M; Perner, Anders

    2014-01-01

    We aimed to elucidate platelet function in trauma patients, as it is pivotal for hemostasis yet remains scarcely investigated in this population. We conducted a prospective observational study of platelet aggregation capacity in 213 adult trauma patients on admission to an emergency department (ED...... severity score (ISS) was 17; 14 (7%) patients received 10 or more units of red blood cells in the ED (massive transfusion); 24 (11%) patients died within 28 days of trauma: 17 due to cerebral injuries, four due to exsanguination, and three from other causes. No significant association was found between...... aggregation response and ISS. Higher TRAP values were associated with death due to cerebral injuries (P 

  3. Sponge cell reaggregation: Cellular structure and morphogenetic potencies of multicellular aggregates.

    Science.gov (United States)

    Lavrov, Andrey I; Kosevich, Igor A

    2016-02-01

    Sponges (phylum Porifera) are one of the most ancient extant multicellular animals and can provide valuable insights into origin and early evolution of Metazoa. High plasticity of cell differentiations and anatomical structure is characteristic feature of sponges. Present study deals with sponge cell reaggregation after dissociation as the most outstanding case of sponge plasticity. Dynamic of cell reaggregation and structure of multicellular aggregates of three demosponge species (Halichondria panicea (Pallas, 1766), Haliclona aquaeductus (Sсhmidt, 1862), and Halisarca dujardinii Johnston, 1842) were studied. Sponge tissue dissociation was performed mechanically. Resulting cell suspensions were cultured at 8-10°C for at least 5 days. Structure of multicellular aggregates was studied by light, transmission and scanning electron microscopy. Studied species share common stages of cell reaggregation-primary multicellular aggregates, early-stage primmorphs and primmorphs, but the rate of reaggregation varies considerably among species. Only cells of H. dujardinii are able to reconstruct functional and viable sponge after primmorphs formation. Sponge reconstruction in this species occurs due to active cell locomotion. Development of H. aquaeductus and H. panicea cells ceases at the stages of early primmorphs and primmorphs, respectively. Development of aggregates of these species is most likely arrested due to immobility of the majority of cells inside them. However, the inability of certain sponge species to reconstruct functional and viable individuals during cell reaggregation may be not a permanent species-specific characteristic, but depends on various factors, including the stage of the life cycle and experimental conditions. © 2016 Wiley Periodicals, Inc.

  4. In vitro motility evaluation of aggregated cancer cells by means of automatic image processing.

    Science.gov (United States)

    De Hauwer, C; Darro, F; Camby, I; Kiss, R; Van Ham, P; Decaesteker, C

    1999-05-01

    Set up of an automatic image processing based method that enables the motility of in vitro aggregated cells to be evaluated for a number of hours. Our biological model included the PC-3 human prostate cancer cell line growing as a monolayer on the bottom of Falcon plastic dishes containing conventional culture media. Our equipment consisted of an incubator, an inverted phase contrast microscope, a Charge Coupled Device (CCD) video camera, and a computer equipped with an image processing software developed in our laboratory. This computer-assisted microscope analysis of aggregated cells enables global cluster motility to be evaluated. This analysis also enables the trajectory of each cell to be isolated and parametrized within a given cluster or, indeed, the trajectories of individual cells outside a cluster. The results show that motility inside a PC-3 cluster is not restricted to slight motion due to cluster expansion, but rather consists of a marked cell movement within the cluster. The proposed equipment enables in vitro aggregated cell motility to be studied. This method can, therefore, be used in pharmacological studies in order to select anti-motility related compounds. The compounds selected by the equipment described could then be tested in vivo as potential anti-metastatic.

  5. Resistance of multicellular aggregates to pharmorubicin observed in human hepatocarcinoma cells

    Directory of Open Access Journals (Sweden)

    Z. Jianmin

    2002-02-01

    Full Text Available The objective of the present study was to investigate the multicellular resistance of human hepatocarcinoma cells BEL-7402 to pharmorubicin. Cells (1 x 10(4 and 200 microcarrier Cytodex-3 beads were seeded onto a 24-well plate and cultured in RPMI 1640 medium. After the formation of multicellular aggregates, morphology and cell viability were analyzed by scanning electron microscopy, transmission electron microscopy and flow cytometry, respectively. The IC50 was determined by flow cytometry and MTT assay after the cells cultured in aggregates and monolayers were treated with pharmorubicin. The culture products exhibited structural characteristics somewhat similar to those of trabecular hepatocarcinoma in vivo. Among the microcarriers, cells were organized into several layers. Intercellular spaces were 0.5-2.0 µm wide and filled with many microvilli. The percent of viable cells was 87%. The cells cultured as multicellular aggregates were resistant to pharmorubicin with IC50 4.5-fold and 7.7-fold that of monolayer culture as determined by flow cytometry and MTT assay, respectively. This three-dimensional culture model may be used to investigate the mechanisms of multicellular drug resistance of hepatocarcinoma and to screen new anticancer drugs.

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

    Science.gov (United States)

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

    2015-08-11

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

  7. 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.

  8. 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.

  9. Fabrication of fluorescent silica nanoparticles with aggregation-induced emission luminogens for cell imaging.

    Science.gov (United States)

    Chen, Sijie; Lam, Jacky W Y; Tang, Ben Zhong

    2013-01-01

    Fluorescence-based techniques have found wide applications in life science. Among various luminogenic materials, fluorescent nanoparticles have attracted much attention due to their fabulous emission properties and potential applications as sensors. Here, we describe the fabrication of fluorescent silica nanoparticles (FSNPs) containing aggregation-induced emission (AIE) luminogens. By employing surfactant-free sol-gel reaction, FSNPs with uniform size and high surface charge and colloidal stability are generated. The FSNPs emit strong light upon photoexcitation, due to the AIE characteristic of the silole -aggregates in the hybrid nanoparticles. The FSNPs are cytocompatible and can be utilized as fluorescent visualizer for intracellular imaging for HeLa cells.

  10. 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

  11. 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...

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

    African Journals Online (AJOL)

    Uche

    Background: Umbilical cord blood analysis may give a clue to the state of health of both pregnant mothers and their neonates. However ... Keywords: Umbilical cord blood; maternal blood; haemoglobin concentration; packed cell volume; red cell indices. Received on .... The packed cell volume was measured using the.

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

    Science.gov (United States)

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

    2015-12-01

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

  14. Protein carbonylation, protein aggregation and neuronal cell death in a murine model of multiple sclerosis

    Science.gov (United States)

    Dasgupta, Anushka

    Many studies have suggested that oxidative stress plays an important role in the pathophysiology of both multiple sclerosis (MS) and its animal model experimental autoimmune encephalomyelitis (EAE). Yet, the mechanism by which oxidative stress leads to tissue damage in these disorders is unclear. Recent work from our laboratory has revealed that protein carbonylation, a major oxidative modification caused by severe and/or chronic oxidative stress conditions, is elevated in MS and EAE. Furthermore, protein carbonylation has been shown to alter protein structure leading to misfolding/aggregation. These findings prompted me to hypothesize that carbonylated proteins, formed as a consequence of oxidative stress and/or decreased proteasomal activity, promote protein aggregation to mediate neuronal apoptosis in vitro and in EAE. To test this novel hypothesis, I first characterized protein carbonylation, protein aggregation and apoptosis along the spinal cord during the course of myelin-oligodendrocyte glycoprotein (MOG)35-55 peptide-induced EAE in C57BL/6 mice [Chapter 2]. The results show that carbonylated proteins accumulate throughout the course of the disease, albeit by different mechanisms: increased oxidative stress in acute EAE and decreased proteasomal activity in chronic EAE. I discovered not only that there is a temporal correlation between protein carbonylation and apoptosis but also that carbonyl levels are significantly higher in apoptotic cells. A high number of juxta-nuclear and cytoplasmic protein aggregates containing the majority of the oxidized proteins are also present during the course of EAE, which seems to be due to reduced autophagy. In chapter 3, I show that when gluthathione levels are reduced to those in EAE spinal cord, both neuron-like PC12 (nPC12) cells and primary neuronal cultures accumulate carbonylated proteins and undergo cell death (both by necrosis and apoptosis). Immunocytochemical and biochemical studies also revealed a temporal

  15. Size- and time-dependent growth properties of human induced pluripotent stem cells in the culture of single aggregate.

    Science.gov (United States)

    Nath, Suman C; Horie, Masanobu; Nagamori, Eiji; Kino-Oka, Masahiro

    2017-10-01

    Aggregate culture of human induced pluripotent stem cells (hiPSCs) is a promising method to obtain high number of cells for cell therapy applications. This study quantitatively evaluated the effects of initial cell number and culture time on the growth of hiPSCs in the culture of single aggregate. Small size aggregates ((1.1 ± 0.4) × 10 1 -(2.8 ± 0.5) × 10 1 cells/aggregate) showed a lower growth rate in comparison to medium size aggregates ((8.8 ± 0.8) × 10 1 -(6.8 ± 1.1) × 10 2 cells/aggregate) during early-stage of culture (24-72 h). However, when small size aggregates were cultured in conditioned medium, their growth rate increased significantly. On the other hand, large size aggregates ((1.1 ± 0.2) × 10 3 -(3.5 ± 1.1) × 10 3 cells/aggregate) showed a lower growth rate and lower expression level of proliferation marker (ki-67) in the center region of aggregate in comparison to medium size aggregate during early-stage of culture. Medium size aggregates showed the highest growth rate during early-stage of culture. Furthermore, hiPSCs proliferation was dependent on culture time because the growth rate decreased significantly during late-stage of culture (72-120 h) at which point collagen type I accumulated on the periphery of aggregate, suggesting blockage of diffusive transport of nutrients, oxygen and metabolites into and out of the aggregates. Consideration of initial cell number and culture time are important to maintain balance between autocrine factors secretion and extracellular matrix accumulation on the aggregate periphery to achieve optimal growth of hiPSCs in the culture of single aggregate. Copyright © 2017 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  16. Cell Surface Binding and Internalization of Aβ Modulated by Degree of Aggregation

    Directory of Open Access Journals (Sweden)

    David A. Bateman

    2011-01-01

    Full Text Available The amyloid peptides, Aβ40 and Aβ42, are generated through endoproteolytic cleavage of the amyloid precursor protein. Here we have developed a model to investigate the interaction of living cells with various forms of aggregated Aβ40/42. After incubation at endosomal pH 6, we observed a variety of Aβ conformations after 3 (Aβ3, 24 (Aβ24, and 90 hours (Aβ90. Both Aβ4224 and Aβ4024 were observed to rapidly bind and internalize into differentiated PC12 cells, leading to accumulation in the lysosome. In contrast, Aβ40/4290 were both found to only weakly associate with cells, but were observed as the most aggregated using dynamic light scattering and thioflavin-T. Internalization of Aβ40/4224 was inhibited with treatment of monodansylcadaverine, an endocytosis inhibitor. These studies indicate that the ability of Aβ40/42 to bind and internalize into living cells increases with degree of aggregation until it reaches a maximum beyond which its ability to interact with cells diminishes drastically.

  17. Self-organising aggregates of zebrafish retinal cells for investigating mechanisms of neural lamination.

    Science.gov (United States)

    Eldred, Megan K; Charlton-Perkins, Mark; Muresan, Leila; Harris, William A

    2017-03-15

    To investigate the cell-cell interactions necessary for the formation of retinal layers, we cultured dissociated zebrafish retinal progenitors in agarose microwells. Within these wells, the cells re-aggregated within hours, forming tight retinal organoids. Using a Spectrum of Fates zebrafish line, in which all different types of retinal neurons show distinct fluorescent spectra, we found that by 48 h in culture, the retinal organoids acquire a distinct spatial organisation, i.e. they became coarsely but clearly laminated. Retinal pigment epithelium cells were in the centre, photoreceptors and bipolar cells were next most central and amacrine cells and retinal ganglion cells were on the outside. Image analysis allowed us to derive quantitative measures of lamination, which we then used to find that Müller glia, but not RPE cells, are essential for this process. © 2017. Published by The Company of Biologists Ltd.

  18. 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)

  19. Bioengineering of injectable encapsulated aggregates of pluripotent stem cells for therapy of myocardial infarction

    Science.gov (United States)

    Zhao, Shuting; Xu, Zhaobin; Wang, Hai; Reese, Benjamin E.; Gushchina, Liubov V.; Jiang, Meng; Agarwal, Pranay; Xu, Jiangsheng; Zhang, Mingjun; Shen, Rulong; Liu, Zhenguo; Weisleder, Noah; He, Xiaoming

    2016-10-01

    It is difficult to achieve minimally invasive injectable cell delivery while maintaining high cell retention and animal survival for in vivo stem cell therapy of myocardial infarction. Here we show that pluripotent stem cell aggregates pre-differentiated into the early cardiac lineage and encapsulated in a biocompatible and biodegradable micromatrix, are suitable for injectable delivery. This method significantly improves the survival of the injected cells by more than six-fold compared with the conventional practice of injecting single cells, and effectively prevents teratoma formation. Moreover, this method significantly enhances cardiac function and survival of animals after myocardial infarction, as a result of a localized immunosuppression effect of the micromatrix and the in situ cardiac regeneration by the injected cells.

  20. 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...

  1. 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

  2. Chondrogenesis and hypertrophy in response to aggregate behaviors of human mesenchymal stem cells on a dendrimer-immobilized surface.

    Science.gov (United States)

    Wongin, Sopita; Ogawa, Yuuki; Kim, Mee-Hae; Viravaidya-Pasuwat, Kwanchanok; Kino-Oka, Masahiro

    2017-08-01

    To investigate the behaviors of aggregates of human mesenchymal stem cells (hMSCs) on chondrogenesis and chondrocyte hypertrophy using spatiotemporal expression patterns of chondrogenic (type II collagen) and hypertrophic (type X collagen) markers during chondrogenesis. hMSCs were cultured on either a polystyrene surface or polyamidoamine dendrimer surface with a fifth generation (G5) dendron structure in chondrogenic medium and growth medium. At day 7, cell aggregates without stress fibers formed on the G5 surface and triggered differentiation of hMSCs toward the chondrogenic fate, as indicated by type II collagen being observed while type X collagen was undetectable. In contrast, immunostaining of hMSCs cultured on polystyrene, which exhibited abundant stress fibers and did not form aggregates, revealed no evidence of either type II and or type X collagen. At day 21, the morphological changes of the cell aggregates formed on the G5 surface were suppressed as a result of stress fiber formation. Type II collagen was observed throughout the aggregates whereas type X collagen was detected only at the basal side of the aggregates. Change of cell aggregate behaviors derived from G5 surface alone regulated chondrogenesis and hypotrophy, and this was enhanced by chondrogenic medium. Incubation of hMSCs affects the expression of type II and X collagens via effects on cell aggregate behavior and stress fiber formation.

  3. Autologous blood cell therapies from pluripotent stem cells

    Science.gov (United States)

    Lengerke, Claudia; Daley, George Q.

    2010-01-01

    Summary The discovery of human embryonic stem cells (hESCs) raised promises for a universal resource for cell based therapies in regenerative medicine. Recently, fast-paced progress has been made towards the generation of pluripotent stem cells (PSCs) amenable for clinical applications, culminating in reprogramming of adult somatic cells to autologous PSCs that can be indefinitely expanded in vitro. However, besides the efficient generation of bona fide, clinically safe PSCs (e.g. without the use of oncoproteins and gene transfer based on viruses inserting randomly into the genome), a major challenge in the field remains how to efficiently differentiate PSCs to specific lineages and how to select for cells that will function normally upon transplantation in adults. In this review, we analyse the in vitro differentiation potential of PSCs to the hematopoietic lineage discussing blood cell types that can be currently obtained, limitations in derivation of adult-type HSCs and prospects for clinical application of PSCs-derived blood cells. PMID:19910091

  4. Regulating Molecular Aggregations of Polymers via Ternary Copolymerization Strategy for Efficient Solar Cells.

    Science.gov (United States)

    Wang, Qian; Wang, Yingying; Zheng, Wei; Shahid, Bilal; Qiu, Meng; Wang, Di; Zhu, Dangqiang; Yang, Renqiang

    2017-09-20

    For many high-performance photovoltaic materials in polymer solar cells (PSCs), the active layers usually need to be spin-coated at high temperature due to the strong intermolecular aggregation of donor polymers, which is unfavorable in device repeatability and large-scale PSC printing. In this work, we adopted a ternary copolymerization strategy to regulate polymer solubility and molecular aggregation. A series of D-A 1 -D-A 2 random polymers based on different acceptors, strong electron-withdrawing unit ester substituted thieno[3,4-b]thiophene (TT-E), and highly planar dithiazole linked TT-E (DTzTT) were constructed to realize the regulation of molecular aggregation and simplification of device fabrication. The results showed that as the relative proportion of TT-E segment in the backbone increased, the absorption evidently red-shifted with a gradually decreased aggregation in solution, eventually leading to the active layers that can be fabricated at low temperature. Furthermore, due to the excellent phase separation and low recombination, the optimized solar cells based on the terpolymer P1 containing 30% of TT-E segment exhibit high power conversion efficiency (PCE) of 9.09% with a significantly enhanced fill factor up to 72.86%. Encouragingly, the photovoltaic performance is insensitive to the fabrication temperature of the active layer, and it still could maintain high PCE of 8.82%, even at room temperature. This work not only develops the highly efficient photovoltaic materials for low temperature processed PSCs through ternary copolymerization strategy but also preliminarily constructs the relationship between aggregation and photovoltaic performance.

  5. Long-term Culture of Human iPS Cell-derived Telencephalic Neuron Aggregates on Collagen Gel.

    Science.gov (United States)

    Oyama, Hiroshi; Takahashi, Koji; Tanaka, Yoshikazu; Takemoto, Hiroshi; Haga, Hisashi

    2018-01-01

    It takes several months to form the 3-dimensional morphology of the human embryonic brain. Therefore, establishing a long-term culture method for neuronal tissues derived from human induced pluripotent stem (iPS) cells is very important for studying human brain development. However, it is difficult to keep primary neurons alive for more than 3 weeks in culture. Moreover, long-term adherent culture to maintain the morphology of telencephalic neuron aggregates induced from human iPS cells is also difficult. Although collagen gel has been widely used to support long-term culture of cells, it is not clear whether human iPS cell-derived neuron aggregates can be cultured for long periods on this substrate. In the present study, we differentiated human iPS cells to telencephalic neuron aggregates and examined long-term culture of these aggregates on collagen gel. The results indicated that these aggregates could be cultured for over 3 months by adhering tightly onto collagen gel. Furthermore, telencephalic neuronal precursors within these aggregates matured over time and formed layered structures. Thus, long-term culture of telencephalic neuron aggregates derived from human iPS cells on collagen gel would be useful for studying human cerebral cortex development.Key words: Induced pluripotent stem cell, forebrain neuron, collagen gel, long-term culture.

  6. Podoplanin enhances lung cancer cell growth in vivo by inducing platelet aggregation.

    Science.gov (United States)

    Miyata, Kenichi; Takemoto, Ai; Okumura, Sakae; Nishio, Makoto; Fujita, Naoya

    2017-06-22

    Podoplanin/Aggrus, known as a platelet aggregation-inducing factor, is frequently overexpressed in lung squamous cell carcinomas (LSCC) and glioblastomas among other tumours, and its expression has been reported to be correlated with poor prognosis. However, the contribution of podoplanin to malignant progression has been elusive. Here we demonstrate that in podoplanin-positive LSCC cells, their growth was abrogated by podoplanin knockout in vivo but not in vitro. Conversely, ectopic expression of podoplanin promoted cell growth in vivo and facilitated intratumoral platelet activation. Consistently, LSCC cells evoked podoplanin-mediated platelet aggregation (PMPA), and the releasates from platelets during PMPA promoted the growth of LSCC cells in vitro. Phospho-receptor-tyrosine-kinase array analysis revealed that epidermal growth factor receptor (EGFR) phosphorylation of LSCC cells was responsible for the growth promotion induced by platelet releasates. Treatment with an antiplatelet agent or podoplanin-neutralizing antibody depressed the growth of an LSCC tumour xenograft via suppression of EGFR phosphorylation. These results suggested that podoplanin in LSCC enhanced cell growth by inducing PMPA in vivo and contributed to malignant progression.

  7. Modulation of invasive phenotype by interstitial pressure-driven convection in aggregates of human breast cancer cells.

    Directory of Open Access Journals (Sweden)

    Joe Tien

    Full Text Available This paper reports the effect of elevated pressure on the invasive phenotype of patterned three-dimensional (3D aggregates of MDA-MB-231 human breast cancer cells. We found that the directionality of the interstitial pressure profile altered the frequency of invasion by cells located at the surface of an aggregate. In particular, application of pressure at one end of an aggregate suppressed invasion at the opposite end. Experimental alteration of the configuration of cell aggregates and computational modeling of the resulting flow and solute concentration profiles revealed that elevated pressure inhibited invasion by altering the chemical composition of the interstitial fluid near the surface of the aggregate. Our data reveal a link between hydrostatic pressure, interstitial convection, and invasion.

  8. Clonorchis sinensis infestation promotes three-dimensional aggregation and invasion of cholangiocarcinoma cells.

    Directory of Open Access Journals (Sweden)

    Jihee Won

    Full Text Available Numerous experimental and epidemiological studies have demonstrated a correlation between Clonorchis sinensis (C. sinensis infestation and cholangiocarcinoma (CCA. However, the role of C. sinensis in the increased invasiveness and proliferation involved in the malignancy of CCA has not been addressed yet. Here, we investigated the possibility that C. sinensis infestation promotes expression of focal and cell-cell adhesion proteins in CCA cells and secretion of matrix metalloproteinases (MMPs. Adhesion proteins help maintain cell aggregates, and MMPs promote the three-dimensional invasion of cells into the neighboring extracellular matrix (ECM. Using a novel microfluidic assay, we quantitatively addressed the role of excretory-secretory products (ESPs gradients from C. sinensis in promoting the invasion of cells into the neighboring ECM.

  9. Optimising cell aggregate expansion in a perfused hollow fibre bioreactor via mathematical modelling.

    KAUST Repository

    Chapman, Lloyd A C

    2014-08-26

    The need for efficient and controlled expansion of cell populations is paramount in tissue engineering. Hollow fibre bioreactors (HFBs) have the potential to meet this need, but only with improved understanding of how operating conditions and cell seeding strategy affect cell proliferation in the bioreactor. This study is designed to assess the effects of two key operating parameters (the flow rate of culture medium into the fibre lumen and the fluid pressure imposed at the lumen outlet), together with the cell seeding distribution, on cell population growth in a single-fibre HFB. This is achieved using mathematical modelling and numerical methods to simulate the growth of cell aggregates along the outer surface of the fibre in response to the local oxygen concentration and fluid shear stress. The oxygen delivery to the cell aggregates and the fluid shear stress increase as the flow rate and pressure imposed at the lumen outlet are increased. Although the increased oxygen delivery promotes growth, the higher fluid shear stress can lead to cell death. For a given cell type and initial aggregate distribution, the operating parameters that give the most rapid overall growth can be identified from simulations. For example, when aggregates of rat cardiomyocytes that can tolerate shear stresses of up to 0:05 Pa are evenly distributed along the fibre, the inlet flow rate and outlet pressure that maximise the overall growth rate are predicted to be in the ranges 2.75 x 10(-5) m(2) s(-1) to 3 x 10(-5) m(2) s(-1) (equivalent to 2.07 ml min(-1) to 2.26 ml min(-1)) and 1.077 x 10(5) Pa to 1.083 x 10(5) Pa (or 15.6 psi to 15.7 psi) respectively. The combined effects of the seeding distribution and flow on the growth are also investigated and the optimal conditions for growth found to depend on the shear tolerance and oxygen demands of the cells.

  10. Conformational Analysis of Misfolded Protein Aggregation by FRET and Live-Cell Imaging Techniques

    Directory of Open Access Journals (Sweden)

    Akira Kitamura

    2015-03-01

    Full Text Available Cellular homeostasis is maintained by several types of protein machinery, including molecular chaperones and proteolysis systems. Dysregulation of the proteome disrupts homeostasis in cells, tissues, and the organism as a whole, and has been hypothesized to cause neurodegenerative disorders, including amyotrophic lateral sclerosis (ALS and Huntington’s disease (HD. A hallmark of neurodegenerative disorders is formation of ubiquitin-positive inclusion bodies in neurons, suggesting that the aggregation process of misfolded proteins changes during disease progression. Hence, high-throughput determination of soluble oligomers during the aggregation process, as well as the conformation of sequestered proteins in inclusion bodies, is essential for elucidation of physiological regulation mechanism and drug discovery in this field. To elucidate the interaction, accumulation, and conformation of aggregation-prone proteins, in situ spectroscopic imaging techniques, such as Förster/fluorescence resonance energy transfer (FRET, fluorescence correlation spectroscopy (FCS, and bimolecular fluorescence complementation (BiFC have been employed. Here, we summarize recent reports in which these techniques were applied to the analysis of aggregation-prone proteins (in particular their dimerization, interactions, and conformational changes, and describe several fluorescent indicators used for real-time observation of physiological states related to proteostasis.

  11. Algorithm for detection of overlapped red blood cells in microscopic images of blood smears

    OpenAIRE

    Romero-Rondón, Miguel Fabián; Sanabria-Rosas, Laura Melissa; Bautista-Rozo, Lola Xiomara; Mendoza-Castellanos, Alfonso

    2016-01-01

    The hemogram is one of the most requested medical tests as it presents details about the three cell series in the blood: red series, white series and platelet series. To make some diagnostics, the specialist must undertake the test manually, observing the blood cells under the microscope, which implies a great physical effort. In order to facilitate this work, different digital image processing techniques to detect and classify red blood cells have been proposed. However, a common problem is ...

  12. Symmetry breaking, germ layer specification and axial organisation in aggregates of mouse embryonic stem cells.

    Science.gov (United States)

    van den Brink, Susanne C; Baillie-Johnson, Peter; Balayo, Tina; Hadjantonakis, Anna-Katerina; Nowotschin, Sonja; Turner, David A; Martinez Arias, Alfonso

    2014-11-01

    Mouse embryonic stem cells (mESCs) are clonal populations derived from preimplantation mouse embryos that can be propagated in vitro and, when placed into blastocysts, contribute to all tissues of the embryo and integrate into the normal morphogenetic processes, i.e. they are pluripotent. However, although they can be steered to differentiate in vitro into all cell types of the organism, they cannot organise themselves into structures that resemble embryos. When aggregated into embryoid bodies they develop disorganised masses of different cell types with little spatial coherence. An exception to this rule is the emergence of retinas and anterior cortex-like structures under minimal culture conditions. These structures emerge from the cultures without any axial organisation. Here, we report that small aggregates of mESCs, of about 300 cells, self-organise into polarised structures that exhibit collective behaviours reminiscent of those that cells exhibit in early mouse embryos, including symmetry breaking, axial organisation, germ layer specification and cell behaviour, as well as axis elongation. The responses are signal specific and uncouple processes that in the embryo are tightly associated, such as specification of the anteroposterior axis and anterior neural development, or endoderm specification and axial elongation. We discuss the meaning and implications of these observations and the potential uses of these structures which, because of their behaviour, we suggest to call 'gastruloids'. © 2014. Published by The Company of Biologists Ltd.

  13. Red Blood Cell.pm6

    African Journals Online (AJOL)

    Adele

    On the other hand, very rapid transfusion of cold blood causes hypothermia which ... Ideally, blood should be heated to reach the body at normal ... Introduction: The practice of warming blood for transfusion by immersion into a waterbath has been investigated. .... One unit of whole blood was obtained from each of 11 volun-.

  14. Zinc chlorophyll aggregates as hole transporters for biocompatible, natural-photosynthesis-inspired solar cells

    Science.gov (United States)

    Li, Yue; Sasaki, Shin-ichi; Tamiaki, Hitoshi; Liu, Cheng-Liang; Song, Jiaxing; Tian, Wenjing; Zheng, Enqiang; Wei, Yingjin; Chen, Gang; Fu, Xueqi; Wang, Xiao-Feng

    2015-11-01

    The intriguing properties of extremely efficient delocalization and migration of excitons in chlorophyll (Chl) J-type aggregates have inspired intense research activities toward their structural understanding, functional interpretation and mimicry synthesis. Herein, we demonstrated the J-aggregates of zinc methyl 3-devinyl-3-hydroxymethyl-pyropheophorbide a (ZnChl-1) generated by spin-coating method for the application as a hole transporter in titania-based solar cells using methyl trans-32-carboxypyropheophorbide a (H2Chl-2) or its zinc complex (ZnChl-2) as the sensitizer. The effective carrier mobility of the J-aggregates films was determined by the organic field-effect transistor to be 6.2 × 10-4 cm2 V-1 s-1. Solar cells sharing the architecture of FTO/H2Chl-2 or ZnChl-2 on TiO2/(ZnChl-1)n/Ag were fabricated and the factors that presumably determine their photovoltaic performances were discussed. The photovoltaic devices studied herein employing inexpensive and pollution-free biomaterials provide a unique solution of utilizing solar energy with a care of the important environmental issue.

  15. 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

  16. Germ-layer commitment and axis formation in sea anemone embryonic cell aggregates.

    Science.gov (United States)

    Kirillova, Anastasia; Genikhovich, Grigory; Pukhlyakova, Ekaterina; Demilly, Adrien; Kraus, Yulia; Technau, Ulrich

    2018-02-20

    Robust morphogenetic events are pivotal for animal embryogenesis. However, comparison of the modes of development of different members of a phylum suggests that the spectrum of developmental trajectories accessible for a species might be far broader than can be concluded from the observation of normal development. Here, by using a combination of microsurgery and transgenic reporter gene expression, we show that, facing a new developmental context, the aggregates of dissociated embryonic cells of the sea anemone Nematostella vectensis take an alternative developmental trajectory. The self-organizing aggregates rely on Wnt signals produced by the cells of the original blastopore lip organizer to form body axes but employ morphogenetic events typical for normal development of distantly related cnidarians to re-establish the germ layers. The reaggregated cells show enormous plasticity including the capacity of the ectodermal cells to convert into endoderm. Our results suggest that new developmental trajectories may evolve relatively easily when highly plastic embryonic cells face new constraints. Copyright © 2018 the Author(s). Published by PNAS.

  17. Silicification-induced cell aggregation for the sustainable production of H2 under aerobic conditions.

    Science.gov (United States)

    Xiong, Wei; Zhao, Xiaohong; Zhu, Genxing; Shao, Changyu; Li, Yaling; Ma, Weimin; Xu, Xurong; Tang, Ruikang

    2015-10-05

    Photobiological hydrogen production is of great importance because of its promise for generating clean renewable energy. In nature, green algae cannot produce hydrogen as a result of the extreme sensitivity of hydrogenase to oxygen. However, we find that silicification-induced green algae aggregates can achieve sustainable photobiological hydrogen production even under natural aerobic conditions. The core-shell structure of the green algae aggregates creates a balance between photosynthetic electron generation and hydrogenase activity, thus allowing the production of hydrogen. This finding provides a viable pathway for the solar-driven splitting of water into hydrogen and oxygen to develop green energy alternatives by using rationally designed cell-material complexes. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. 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.

  19. 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.

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

    Science.gov (United States)

    Chico, Verónica; Puente-Marin, Sara; Ciordia, Sergio; Mena, María Carmen; Carracedo, Begoña; Mercado, Luis; Coll, Julio

    2018-01-01

    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. PMID:29671811

  1. Raman spectroscopic studies of optically trapped red blood cells

    International Nuclear Information System (INIS)

    Dasgupta, R.; Gupta, P.K.

    2010-01-01

    Raman spectroscopic studies were performed on optically trapped red blood cells (RBCs) collected from healthy volunteers and patients suffering from malaria (Plasmodium vivax infection) using near infrared (785 nm) laser source. The results show significant alteration in the spectra averaged over ∼ 50 non-parasitized RBCs per sample. As compared to RBCs from healthy donors, in cells collected from malaria patients, a significant decrease in the intensity of the low spin (oxygenated-haemoglobin) marker Raman band at 1223 cm -1 (υ 13 or υ 42 ) along with a concomitant increase in the high spin (deoxygenated-haemoglobin) marker bands at 1210 cm -1 (υ 5 + υ 18 ) and 1546 cm -1 (υ 11 ) was observed. The changes primarily suggest a reduced haemoglobin-oxygen affinity for the non-parasitized red cells in malaria patients. The possible causes include up regulation of intra-erythrocytic 2,3-diphosphoglycerate and/or ineffective erythropoiesis resulted from the disease. During the above study we also observed that significant photo-damage may results to the intracellular haemoglobin (Hb) if higher laser power is used. For a laser power above ∼ 5 mW the observed increase in intensity of the Raman bands at 975 cm -1 (υ 46 ), 1244 cm -1 (υ 42 ) and 1366 cm -1 (υ 4 ) with increasing exposure time suggests photo-denaturation of Hb and the concomitant decrease in intensity of the Raman band at 1544 cm -1 (υ 11 ) suggests photo induced methaemoglobin formation. The photo damage of intracellular haemoglobin by the above processes was also observed to result in intracellular heme aggregation. (author)

  2. Entamoeba Clone-Recognition Experiments: Morphometrics, Aggregative Behavior, and Cell-Signaling Characterization.

    Science.gov (United States)

    Espinosa, Avelina; Paz-Y-Miño-C, Guillermo; Hackey, Meagan; Rutherford, Scott

    2016-05-01

    Studies on clone- and kin-discrimination in protists have proliferated during the past decade. We report clone-recognition experiments in seven Entamoeba lineages (E. invadens IP-1, E. invadens VK-1:NS, E. terrapinae, E. moshkovskii Laredo, E. moshkovskii Snake, E. histolytica HM-1:IMSS and E. dispar). First, we characterized morphometrically each clone (length, width, and cell-surface area) and documented how they differed statistically from one another (as per single-variable or canonical-discriminant analyses). Second, we demonstrated that amebas themselves could discriminate self (clone) from different (themselves vs. other clones). In mix-cell-line cultures between closely-related (E. invadens IP-1 vs. E. invadens VK-1:NS) or distant-phylogenetic clones (E. terrapinae vs. E. moshkovskii Laredo), amebas consistently aggregated with same-clone members. Third, we identified six putative cell-signals secreted by the amebas (RasGap/Ankyrin, coronin-WD40, actin, protein kinases, heat shock 70, and ubiquitin) and which known functions in Entamoeba spp. included: cell proliferation, cell adhesion, cell movement, and stress-induced encystation. To our knowledge, this is the first multi-clone characterization of Entamoeba spp. morphometrics, aggregative behavior, and cell-signaling secretion in the context of clone-recognition. Protists allow us to study cell-cell recognition from ecological and evolutionary perspectives. Modern protistan lineages can be central to studies about the origins and evolution of multicellularity. © 2016 The Author(s) Journal of Eukaryotic Microbiology © 2016 International Society of Protistologists.

  3. Effect of 2,3-diphosphoglycerate on oxygen affinity of blood in sickle cell anemia

    Science.gov (United States)

    Charache, Samuel; Grisolia, Santiago; Fiedler, Adam J.; Hellegers, Andre E.

    1970-01-01

    Blood of patients with sickle cell anemia (SS) exhibits decreased affinity for oxygen, although the oxygen affinity of hemoglobin S is the same as that of hemoglobin A. SS red cells contain more 2,3-diphosphoglycerate (DPG) than normal erythrocytes. The oxygen affinity of hemolyzed red cells is decreased by added DPG, and hemolysates prepared from SS red cells do not differ from normal hemolysates in this regard. Reduction of oxygen affinity to the levels found in intact SS red cells required DPG concentrations in excess of those found in most SS patients. The same was true of oxygen affinity of patients with pyruvate kinase deficiency. Other organic phosphates, as well as inorganic ions, are known to alter the oxygen affinity of dilute solutions of hemoglobin. These substances, the state of aggregation of hemoglobin molecules, and cytoarchitectural factors probably play roles in determining oxygen affinity of both normal and SS red cells. PMID:5443181

  4. [Experimental-morphological study of morphogenetic potencies of homogeneous aggregates of different types of cells from the freshwater sponge Ephydatia fluviatilis (L.)].

    Science.gov (United States)

    Nikitin, N S

    1977-01-01

    The morphogenetic potencies of somatic cells of the fresh-water sponge Ephydatia fluviatilis in the developing aggregates depend on their initial specialization and the number of cells in the aggregate. The aggregates of nucleolar amoebocytes consisting of 500 or more cells have the highest morphogenetic potencies. All main cell types can arise in the developing homogeneous aggregates of nucleolar amoebocytes. The fine structure of nucleolar amoebocytes at different stages of development of the homogeneous aggregates was studied by means of electron microscopy. The structural rearrangements are described which accompany the process of redifferentiation of the nucleolar amoebocytes in other cell types.

  5. 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...... proteome have been confirmed here. This comparison sheds light on several open issues in RBC biology and provides a departure point for more comprehensive understanding of RBC function....

  6. Mechanisms of the priming effect of low doses of lipopoly-saccharides on leukocyte-dependent platelet aggregation in whole blood.

    Science.gov (United States)

    Montrucchio, Giuseppe; Bosco, Ornella; Del Sorbo, Lorenzo; Fascio Pecetto, Paolo; Lupia, Enrico; Goffi, Alberto; Omedè, Paola; Emanuelli, Giorgio; Camussi, Giovanni

    2003-11-01

    Several studies focused on the ability of bacterial lipopolysac-charides (LPS) in triggering platelet and/or leukocyte activation. The aim of this study was to investigate the molecular mechanisms involved in the aggregation of platelets and in their interaction with leukocytes in whole blood after stimulation with low doses of LPS. LPS did not directly induce platelet aggregation in whole blood, but they primed the aggregation of platelets induced by epinephrine, adenosine diphosphate and arachidonic acid. As shown by cytofluorimetry, platelets neither bind FITC-LPS, nor express the LPS-receptors CD14 and toll-like receptor 4 (TLR4). On the contrary, LPS primed monocytes and to a lesser extent polymorphonuclear neutrophils to adhere to platelets. Both platelet-leukocyte interaction and platelet aggregation in whole blood were inhibited by blockade of CD14 and TLR4. Moreover, the interaction between platelets and leukocytes was inhibited by P-selectin, and by blockade of PAF and reactive oxygen species, suggesting a role of P-selectin and of leukocyte-derived mediators. In conclusion, these results elucidate the mechanisms leading to platelet activation and interaction with leukocytes triggered by LPS. They suggest that the activation of platelets by LPS is mainly dependent on leukocytes and especially monocytes as a result of CD14 and TLR4 engagement. Moreover, we found that leukocyte-platelet interaction was triggered by the synthesis of PAF and the generation of oxygen radicals that induced upregulation of surface expression of P-selectin.

  7. 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.

  8. 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.

  9. Cytotoxicity of cuprous oxide nanoparticles to fish blood cells: hemolysis and internalization

    Energy Technology Data Exchange (ETDEWEB)

    Chen Liqiang, E-mail: chenlq@ynu.edu.cn; Kang Bin [Yunnan University, Asian International Rivers Center, Yunnan Key Laboratory of International Rivers and Trans-boundary Eco-security (China); Ling Jian [Yunnan University, College of Chemistry and Chemical Engineering (China)

    2013-03-15

    Cuprous oxide nanoparticles (Cu{sub 2}O NPs) possess unique physical and chemical properties which are employed in a broad variety of applications. However, little is known about the adverse effects of Cu{sub 2}O NPs on organisms. In the current study, in vitro cytotoxicity of Cu{sub 2}O NPs (ca. 60 nm in diameter) to the blood cells of freshwater fish Carassius auratus was evaluated. A concentration-dependent hemolytic activity of Cu{sub 2}O NPs to red blood cells (RBCs) and the phagocytosis of Cu{sub 2}O NPs by leukocytes were revealed. The results showed that dosages of Cu{sub 2}O NPs greater than 40 {mu}g/mL were toxic to blood cells, and could cause serious membrane damage to RBCs. The EC{sub 50} value of Cu{sub 2}O NPs as obtained from RBCs and whole blood exposure was 26 and 63 {mu}g/mL, respectively. The generation of reactive oxygen species and the direct interaction between Cu{sub 2}O NPs and the cell membrane were suggested as the possible mechanism for cytotoxicity, and the intrinsic hemolytic active of Cu{sub 2}O NPs was the main contributor to the toxicity rather than solubilized copper ions. The adsorption of plasma proteins on the surfaces of Cu{sub 2}O NPs led to their aggregation in whole blood, and aggregate formation can significantly alleviate the hemolytic effect and subsequently mediate the phagocytosis of Cu{sub 2}O NPs by leukocytes.

  10. A blood-brain barrier (BBB) disrupter is also a potent α-synuclein (α-syn) aggregation inhibitor: a novel dual mechanism of mannitol for the treatment of Parkinson disease (PD).

    Science.gov (United States)

    Shaltiel-Karyo, Ronit; Frenkel-Pinter, Moran; Rockenstein, Edward; Patrick, Christina; Levy-Sakin, Michal; Schiller, Abigail; Egoz-Matia, Nirit; Masliah, Eliezer; Segal, Daniel; Gazit, Ehud

    2013-06-14

    The development of disease-modifying therapy for Parkinson disease has been a main drug development challenge, including the need to deliver the therapeutic agents to the brain. Here, we examined the ability of mannitol to interfere with the aggregation process of α-synuclein in vitro and in vivo in addition to its blood-brain barrier-disrupting properties. Using in vitro studies, we demonstrated the effect of mannitol on α-synuclein aggregation. Although low concentration of mannitol inhibited the formation of fibrils, high concentration significantly decreased the formation of tetramers and high molecular weight oligomers and shifted the secondary structure of α-synuclein from α-helical to a different structure, suggesting alternative potential pathways for aggregation. When administered to a Parkinson Drosophila model, mannitol dramatically corrected its behavioral defects and reduced the amount of α-synuclein aggregates in the brains of treated flies. In the mThy1-human α-synuclein transgenic mouse model, a decrease in α-synuclein accumulation was detected in several brain regions following treatment, suggesting that mannitol promotes α-synuclein clearance in the cell bodies. It appears that mannitol has a general neuroprotective effect in the transgenic treated mice, which includes the dopaminergic system. We therefore suggest mannitol as a basis for a dual mechanism therapeutic agent for the treatment of Parkinson disease.

  11. 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

  12. Glyceraldehyde-3-phosphate dehydrogenase aggregation inhibitor peptide: A potential therapeutic strategy against oxidative stress-induced cell death.

    Science.gov (United States)

    Itakura, Masanori; Nakajima, Hidemitsu; Semi, Yuko; Higashida, Shusaku; Azuma, Yasu-Taka; Takeuchi, Tadayoshi

    2015-11-13

    The glycolytic enzyme glyceraldehyde-3-phosphate dehydrogenase (GAPDH) has multiple functions, including mediating oxidative stress-induced neuronal cell death. This process is associated with disulfide-bonded GAPDH aggregation. Some reports suggest a link between GAPDH and the pathogenesis of several oxidative stress-related diseases. However, the pathological significance of GAPDH aggregation in disease pathogenesis remains unclear due to the lack of an effective GAPDH aggregation inhibitor. In this study, we identified a GAPDH aggregation inhibitor (GAI) peptide and evaluated its biological profile. The decapeptide GAI specifically inhibited GAPDH aggregation in a concentration-dependent manner. Additionally, the GAI peptide did not affect GAPDH glycolytic activity or cell viability. The GAI peptide also exerted a protective effect against oxidative stress-induced cell death in SH-SY5Y cells. This peptide could potentially serve as a tool to investigate GAPDH aggregation-related neurodegenerative and neuropsychiatric disorders and as a possible therapy for diseases associated with oxidative stress-induced cell death. Copyright © 2015 Elsevier Inc. All rights reserved.

  13. 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.

  14. 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.

  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. 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).

  17. 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

  18. Stem cells of umbilical blood cord – therapeutic use

    Directory of Open Access Journals (Sweden)

    Beata Bielec

    2015-07-01

    Full Text Available For many years, the transplantation of hematopoietic stem cells has been used to treat some diseases of the hematopoietic system. For a very long time, only bone marrow was used as a source of hematopoietic stem cells for this method of treatment. However, to comply with allogeneic bone marrow transplantation, an antigenically compatible donor is necessary. Transplantations from unrelated donors are associated with increased risk of a graft-versus-host reaction, transplant rejection and, consequently, increased mortality. Many years ago, it was found that umbilical cord blood as well as bone marrow and peripheral blood contains hematopoietic stem cells and mesenchymal cells able to differentiate into different cell types and that the umbilical cord blood can be a source of stem cells for transplantation. Following this discovery, numerous attempts were made for its potential use in the treatment of hematologic diseases, metabolic diseases as well as regenerative medicine. Umbilical cord blood stem cells exhibit intermediate characteristics between embryonic and adult stem cells. They are distinguished from the latter by telomere length, telomerase activity, and lower risk of accumulation of DNA mutations or chromosomal aberrations. The only transplantation limitation appears to be the amount of cord blood collected, which on average is sufficient for transplantation in a 40-50 kg child. Collection of cord blood is a simple, short-lasting treatment, not causing any danger for a newborn or the mother. Umbilical cord blood is obtained during labor, and then frozen and stored at cord blood banks all over the world.

  19. 21 CFR 864.8200 - Blood cell diluent.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Blood cell diluent. 864.8200 Section 864.8200 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Reagents § 864.8200 Blood cell diluent. (a...

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

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Red blood cell enzyme assay. 864.7100 Section 864.7100 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Kits and Packages § 864.7100 Red blood cell...

  1. 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

  2. A photonic crystal hydrogel suspension array for the capture of blood cells from whole blood

    Science.gov (United States)

    Zhang, Bin; Cai, Yunlang; Shang, Luoran; Wang, Huan; Cheng, Yao; Rong, Fei; Gu, Zhongze; Zhao, Yuanjin

    2016-02-01

    Diagnosing hematological disorders based on the separation and detection of cells in the patient's blood is a significant challenge. We have developed a novel barcode particle-based suspension array that can simultaneously capture and detect multiple types of blood cells. The barcode particles are polyacrylamide (PAAm) hydrogel inverse opal microcarriers with characteristic reflection peak codes that remain stable during cell capture on their surfaces. The hydrophilic PAAm hydrogel scaffolds of the barcode particles can entrap various plasma proteins to capture different cells in the blood, with little damage to captured cells.Diagnosing hematological disorders based on the separation and detection of cells in the patient's blood is a significant challenge. We have developed a novel barcode particle-based suspension array that can simultaneously capture and detect multiple types of blood cells. The barcode particles are polyacrylamide (PAAm) hydrogel inverse opal microcarriers with characteristic reflection peak codes that remain stable during cell capture on their surfaces. The hydrophilic PAAm hydrogel scaffolds of the barcode particles can entrap various plasma proteins to capture different cells in the blood, with little damage to captured cells. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr06368j

  3. Margination of Stiffened Red Blood Cells Regulated By Vessel Geometry.

    Science.gov (United States)

    Chen, Yuanyuan; Li, Donghai; Li, Yongjian; Wan, Jiandi; Li, Jiang; Chen, Haosheng

    2017-11-10

    Margination of stiffened red blood cells has been implicated in many vascular diseases. Here, we report the margination of stiffened RBCs in vivo, and reveal the crucial role of the vessel geometry in the margination by calculations when the blood is seen as viscoelastic fluid. The vessel-geometry-regulated margination is then confirmed by in vitro experiments in microfluidic devices, and it establishes new insights to cell sorting technology and artificial blood vessel fabrication.

  4. Putative porcine embryonic stem cell lines derived from aggregated four-celled cloned embryos produced by oocyte bisection cloning.

    Science.gov (United States)

    Siriboon, Chawalit; Lin, Yu-Hsuan; Kere, Michel; Chen, Chun-Da; Chen, Lih-Ren; Chen, Chien-Hong; Tu, Ching-Fu; Lo, Neng-Wen; Ju, Jyh-Cherng

    2015-01-01

    We attempted to isolate ES cell lines using inner cell masses from high-quality cloned porcine blastocysts. After being seeded onto feeders, embryos had better (P cloned embryos (62.8, 42.6 and 12.8% vs. 76.2, 55.2 and 26.2%, respectively) compared to the non-aggregated group (41.6, 23.4 and 3.9%). Effects of feeder types (STO vs. MEF) and serum sources (FBS vs. KSR) on extraction of cloned embryo-derived porcine ES cells were examined. More (17.1%) ntES cell lines over Passage 3 were generated in the MEF/KSR group. However, ntES cells cultured in KSR-supplemented medium had a low proliferation rate with defective morphology, and eventually underwent differentiation or apoptosis subsequently. Approximately 26.1, 22.7 and 35.7% of primary colonies were formed after plating embryos in DMEM, DMEM/F12 and α-MEM media, respectively. Survival rates of ntES cells cultured in α-MEM, DMEM and DMEM/F12 were 16.7, 4.3 and 6.8%, respectively (P > 0.05). We further examined the beneficial effect of TSA treatment of 3× aggregated cloned embryos on establishment of ntES cell lines. Primary colony numbers and survival rates of ntES cells beyond passage 3 were higher (P cells, remaining undifferentiated over 25 passages, had alkaline phosphatase activity and expressed ES specific markers Oct4, Nanog, Sox2, and Rex01. Moreover, these ntES cells successfully differentiated into embryoid bodies (EBs) that expressed specific genes of all three germ layers after being cultured in LIF-free medium. In conclusion, we have successfully derived putative porcine ntES cells with high efficiency from quality cloned embryos produced by embryo aggregation, and optimized the ES cell culture system suitable for establishing and maintaining ntES cell lines in undifferentiated state.

  5. The counting of native blood cells by digital microscopy

    Science.gov (United States)

    Torbin, S. O.; Doubrovski, V. A.; Zabenkov, I. V.; Tsareva, O. E.

    2017-03-01

    An algorithm for photographic images processing of blood samples in its native state was developed to determine the concentration of erythrocytes, leukocytes and platelets without individual separate preparation of cells' samples. Special "photo templates" were suggested to use in order to identify red blood cells. The effect of "highlighting" of leukocytes, which was found by authors, was used to increase the accuracy of this type of cells counting. Finally to raise the resolution of platelets from leukocytes the areas of their photo images were used, but not their sizes. It is shown that the accuracy of cells counting for native blood samples may be comparable with the accuracy of similar studies for smears. At the same time the proposed native blood analysis simplifies greatly the procedure of sample preparation in comparison to smear, permits to move from the detection of blood cells ratio to the determination of their concentrations in the sample.

  6. 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.

  7. Biogrid--a microfluidic device for large-scale enzyme-free dissociation of stem cell aggregates.

    Science.gov (United States)

    Wallman, Lars; Åkesson, Elisabet; Ceric, Dario; Andersson, Per Henrik; Day, Kelly; Hovatta, Outi; Falci, Scott; Laurell, Thomas; Sundström, Erik

    2011-10-07

    Culturing stem cells as free-floating aggregates in suspension facilitates large-scale production of cells in closed systems, for clinical use. To comply with GMP standards, the use of substances such as proteolytic enzymes should be avoided. Instead of enzymatic dissociation, the growing cell aggregates may be mechanically cut at passage, but available methods are not compatible with large-scale cell production and hence translation into the clinic becomes a severe bottle-neck. We have developed the Biogrid device, which consists of an array of micrometerscale knife edges, micro-fabricated in silicon, and a manifold in which the microgrid is placed across the central fluid channel. By connecting one side of the Biogrid to a syringe or a pump and the other side to the cell culture, the culture medium with suspended cell aggregates can be aspirated, forcing the aggregates through the microgrid, and ejected back to the cell culture container. Large aggregates are thereby dissociated into smaller fragments while small aggregates pass through the microgrid unaffected. As proof-of-concept, we demonstrate that the Biogrid device can be successfully used for repeated passage of human neural stem/progenitor cells cultured as so-called neurospheres, as well as for passage of suspension cultures of human embryonic stem cells. We also show that human neural stem/progenitor cells tolerate transient pressure changes far exceeding those that will occur in a fluidic system incorporating the Biogrid microgrids. Thus, by using the Biogrid device it is possible to mechanically passage large quantities of cells in suspension cultures in closed fluidic systems, without the use of proteolytic enzymes.

  8. Managing magnetic nanoparticle aggregation and cellular uptake: a precondition for efficient stem-cell differentiation and MRI tracking.

    Science.gov (United States)

    Fayol, Delphine; Luciani, Nathalie; Lartigue, Lenaic; Gazeau, Florence; Wilhelm, Claire

    2013-02-01

    The labeling of stem cells with iron oxide nanoparticles is increasingly used to enable MRI cell tracking and magnetic cell manipulation, stimulating the fields of tissue engineering and cell therapy. However, the impact of magnetic labeling on stem-cell differentiation is still controversial. One compromising factor for successful differentiation may arise from early interactions of nanoparticles with cells during the labeling procedure. It is hypothesized that the lack of control over nanoparticle colloidal stability in biological media may lead to undesirable nanoparticle localization, overestimation of cellular uptake, misleading MRI cell tracking, and further impairment of differentiation. Herein a method is described for labeling mesenchymal stem cells (MSC), in which the physical state of citrate-coated nanoparticles (dispersed versus aggregated) can be kinetically tuned through electrostatic and magnetic triggers, as monitored by diffusion light scattering in the extracellular medium and by optical and electronic microscopy in cells. A set of statistical cell-by-cell measurements (flow cytometry, single-cell magnetophoresis, and high-resolution MRI cellular detection) is used to independently quantify the nanoparticle cell uptake and the effects of nanoparticle aggregation. Such aggregation confounds MRI cell detection as well as global iron quantification and has adverse effects on chondrogenetic differentiation. Magnetic labeling conditions with perfectly stable nanoparticles-suitable for obtaining differentiation-capable magnetic stem cells for use in cell therapy-are subsequently identified. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Fresenius AS.TEC204 blood cell separator.

    Science.gov (United States)

    Sugai, Mikiya

    2003-02-01

    Fresenius AS.TEC204 is a third-generation blood cell separator that incorporates the continuous centrifugal separation method and automatic control of the cell separation process. Continuous centrifugation separates cell components according to their specific gravity, and different cell components are either harvested or eliminated as needed. The interface between the red blood cell and plasma is optically detected, and the Interface Control (IFC) cooperates with different pumps, monitors and detectors to harvest required components automatically. The system is composed of three major sections; the Front Panel Unit; the Pump Unit, and the Centrifuge Unit. This unit can be used for a wide variety of clinical applications including collection of platelets, peripheral blood stem cells, bone marrow stem cells, granulocytes, mononuclear cells, and exchange of plasma or red cells, and for plasma treatment.

  10. Delta-9-tetrahydrocannabinol accumulation, metabolism and cell-type-specific adverse effects in aggregating brain cell cultures

    Energy Technology Data Exchange (ETDEWEB)

    Monnet-Tschudi, Florianne [Department of Physiology, University of Lausanne, 7, rue du Bugnon CH-1005 Lausanne (Switzerland); Hazekamp, Arno [Department of Plant Metabolomics, University of Leiden (Netherlands); Perret, Nicolas; Zurich, Marie-Gabrielle [Department of Physiology, University of Lausanne, 7, rue du Bugnon CH-1005 Lausanne (Switzerland); Mangin, Patrice; Giroud, Christian [Laboratory of Forensic Toxicology and Chemistry, Institute of Legal Medicine, University Hospital Center and University of Lausanne (Switzerland); Honegger, Paul [Department of Physiology, University of Lausanne, 7, rue du Bugnon CH-1005 Lausanne (Switzerland)

    2008-04-01

    Despite the widespread use of Cannabis as recreational drug or as medicine, little is known about its toxicity. The accumulation, metabolism and toxicity of THC were analyzed 10 days after a single treatment, and after repeated exposures during 10 days. Mixed-cell aggregate cultures of fetal rat telencephalon were used as in vitro model, as well as aggregates enriched either in neurons or in glial cells. It was found that THC accumulated preferentially in neurons, and that glia-neuron interactions decreased THC accumulation. The quantification of 11-OH-THC and of THC-COOH showed that brain aggregates were capable of THC metabolism. No cell-type difference was found for the metabolite 11-OH-THC, whereas the THC-COOH content was higher in mixed-cell cultures. No cell death was found at THC concentrations of 2 {mu}M in single treatment and of 1 {mu}M and 2 {mu}M in repeated treatments. Neurons, and particularly GABAergic neurons, were most sensitive to THC. Only the GABAergic marker was affected after the single treatment, whereas the GABAergic, cholinergic and astrocytic markers were decreased after the repeated treatments. JWH 015, a CB2 receptor agonist, showed effects similar to THC, whereas ACEA, a CB1 receptor agonist, had no effect. The expression of the cytokine IL-6 was upregulated 48 h after the single treatment with 5 {mu}M of THC or JWH 015, whereas the expression of TNF-{alpha} remained unchanged. These results suggest that the adverse effects of THC were related either to THC accumulation or to cannabinoid receptor activation and associated with IL-6 upregulation.

  11. Delta-9-tetrahydrocannabinol accumulation, metabolism and cell-type-specific adverse effects in aggregating brain cell cultures

    International Nuclear Information System (INIS)

    Monnet-Tschudi, Florianne; Hazekamp, Arno; Perret, Nicolas; Zurich, Marie-Gabrielle; Mangin, Patrice; Giroud, Christian; Honegger, Paul

    2008-01-01

    Despite the widespread use of Cannabis as recreational drug or as medicine, little is known about its toxicity. The accumulation, metabolism and toxicity of THC were analyzed 10 days after a single treatment, and after repeated exposures during 10 days. Mixed-cell aggregate cultures of fetal rat telencephalon were used as in vitro model, as well as aggregates enriched either in neurons or in glial cells. It was found that THC accumulated preferentially in neurons, and that glia-neuron interactions decreased THC accumulation. The quantification of 11-OH-THC and of THC-COOH showed that brain aggregates were capable of THC metabolism. No cell-type difference was found for the metabolite 11-OH-THC, whereas the THC-COOH content was higher in mixed-cell cultures. No cell death was found at THC concentrations of 2 μM in single treatment and of 1 μM and 2 μM in repeated treatments. Neurons, and particularly GABAergic neurons, were most sensitive to THC. Only the GABAergic marker was affected after the single treatment, whereas the GABAergic, cholinergic and astrocytic markers were decreased after the repeated treatments. JWH 015, a CB2 receptor agonist, showed effects similar to THC, whereas ACEA, a CB1 receptor agonist, had no effect. The expression of the cytokine IL-6 was upregulated 48 h after the single treatment with 5 μM of THC or JWH 015, whereas the expression of TNF-α remained unchanged. These results suggest that the adverse effects of THC were related either to THC accumulation or to cannabinoid receptor activation and associated with IL-6 upregulation

  12. Influence of classical and rock music on red blood cell rheological properties in rats.

    Science.gov (United States)

    Erken, Gulten; Bor Kucukatay, Melek; Erken, Haydar Ali; Kursunluoglu, Raziye; Genc, Osman

    2008-01-01

    A number of studies have reported physiological effects of music. Different types of music have been found to induce different alterations. Although some physiological and psychological parameters have been demonstrated to be influenced by music, the effect of music on hemorheological parameters such as red blood cell (RBC) deformability and aggregation are unknown. This study aimed at investigating the effects of classical and rock music on hemorheological parameters in rats. Twenty-eight rats were divided into four groups: the control, noise-applied, and the classical music- and rock music-applied groups. Taped classical or rock music were played repeatedly for 1 hour a day for 2 weeks and 95-dB machine sound was applied to the noise-applied rats during the same period. RBC deformability and aggregation were measured using an ektacytometer. RBC deformability was found to be increased in the classical music group. Exposure to both classical and rock music resulted in a decrement in erythrocyte aggregation, but the decline in RBC aggregation was of a higher degree of significance in the classical music group. Exposure to noise did not have any effect on the parameters studied. The results of this study indicate that the alterations in hemorheological parameters were more pronounced in the classical music group compared with the rock music group.

  13. Evolution and role of corded cell aggregation in Mycobacterium tuberculosis cultures.

    Science.gov (United States)

    Caceres, Neus; Vilaplana, Cristina; Prats, Clara; Marzo, Elena; Llopis, Isaac; Valls, Joaquim; Lopez, Daniel; Cardona, Pere-Joan

    2013-11-01

    The aim of this study was to evaluate the evolution and role of corded cell aggregation in Mycobacterium tuberculosis cultures according to growth time and conditions. Thus, in standard culture using aerated 7H9 Middlebrook broth supplemented with 0.05% Tween 80, a dramatic CFU decrease was observed at the end of the exponential phase. This phase was followed by a stable stationary phase that led to dissociation between the optical density (O.D.) and CFU values, together with the formation of opaque colonies in solid culture. Further analysis revealed that this was due to cording. Scanning electron microscopy showed that cording led to the formation of very stable coiled structures and corded cell aggregations which proved impossible to disrupt by any of the physical means tested. Modulation of cording with a high but non-toxic concentration of Tween 80 led to a slower growth rate, avoidance of a sudden drop-off to the stationary phase, the formation of weaker cording structures and the absence of opaque colonies, together with a lower survival at later time-points. An innovative automated image analysis technique has been devised to characterize the cording process. This analysis has led to important practical consequences for the elaboration of M. tuberculosis inocula and suggests the importance of biofilm formation in survival of the bacilli in the extracellular milieu. Copyright © 2013. Published by Elsevier Ltd.

  14. Charge Photogeneration Experiments and Theory in Aggregated Squaraine Donor Materials for Improved Organic Solar Cell Efficiencies

    Science.gov (United States)

    Spencer, Susan Demetra

    Fossil fuel consumption has a deleterious effect on humans, the economy, and the environment. Renewable energy technologies must be identified and commercialized as quickly as possible so that the transition to renewables can happen at a minimum of financial and societal cost. Organic photovoltaic cells offer an inexpensive and disruptive energy technology, if the scientific challenges of understanding charge photogeneration in a bulk heterojunction material can be overcome. At RIT, there is a strong focus on creating new materials that can both offer fundamentally important scientific results relating to quantum photophysics, and simultaneously assist in the development of strong candidates for future commercialized technology. In this presentation, the results of intensive materials characterization of a series of squaraine small molecule donors will be presented, as well as a full study of the fabrication and optimization required to achieve >4% photovoltaic cell efficiency. A relationship between the molecular structure of the squaraine and its ability to form nanoscale aggregates will be explored. Squaraine aggregation will be described as a unique optoelectronic probe of the structure of the bulk heterojunction. This relationship will then be utilized to explain changes in crystallinity that impact the overall performance of the devices. Finally, a predictive summary will be given for the future of donor material research at RIT.

  15. Production Pattern of Ajmalicine in Catharanthus roseus (L. G. Don. Cell Aggregates Culture in the Airlift Bioreactor

    Directory of Open Access Journals (Sweden)

    RIZKITA RACHMI ESYANTI

    2006-12-01

    Full Text Available A research has been conducted to optimize the rate of aeration and initial weight of cell aggregates in the production of ajmalicine in Catharanthus roseus cell culture in airlift bioreactor. Catharanthus roseus culture were grown in Zenk medium with the addition of 2.50 x 10-6 M naphthalene acetic acid (NAA and 10-5 M benzyl amino purine (BAP. Cell aggregates were sub-cultured two times before transferring 20 and 30 g/fw of cell aggregates into bioreactor, respectively, and aerated with the rate of 0.25 l min-1 and 0.34 l min-1, respectively. The pattern of ajmalicine production in bioreactor were observed in every three days within 24 days. Qualitative and quantitative analysis were conducted using HPLC connected to Cromatopac CL-7A Plus. The results showed that the cell aggregates and medium contain ajmalicine. The highest concentration was obtained in combination of 30 g/fw and 0.34 l min-1 aeration compare to 20 g/fw - 0.25 l min-1, 20 g/fw - 0.34 l min-1, as well as 30 g/fw – 0.25 l min-1. The highest ajmalicine content in cell aggregates was obtained on the 12 days (79.23 µg g-1 whilst in medium was obtained in the 18th days (981.15 µg l-1.

  16. Effects of helicopter transport on red blood cell components

    Science.gov (United States)

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

    2012-01-01

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

  17. Effects of helicopter transport on red blood cell components.

    Science.gov (United States)

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

    2012-01-01

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

  18. 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

  19. Small-molecule aggregation inhibitors reduce excess amyloid in a trisomy 16 mouse cortical cell line

    Directory of Open Access Journals (Sweden)

    ANDRÉA C PAULA LIMA

    2008-01-01

    Full Text Available We have previously characterized a number of small molecule organic compounds that prevent the aggregation of the β-amyloid peptide and its neurotoxicity in hippocampal neuronal cultures. We have now evaluated the effects of such compounds on amyloid precursor protein (APP accumulation in the CTb immortalized cell line derived from the cerebral cortex of a trisomy 16 mouse, an animal model of Down's syndrome. Compared to a non-trisomic cortical cell line (CNh, CTb cells overexpress APP and exhibit slightly elevated resting intracellular Ca2+ levéis ([Ca2+]¡. Here, we show that the compounds 2,4-dinitrophenol, 3-nitrophenol and 4-anisidine decreased intracellular accumulation of APP in CTb cells. Those compounds were non-toxic to the cells, and slightly increased the basal [Ca2+]¡. Results indícate that the compounds tested can be leads for the development of drugs to decrease intracellular vesicular accumulation of APP in trisomic cells.

  20. Effect of the LHCII pigment-protein complex aggregation on photovoltaic properties of sensitized TiO2 solar cells.

    Science.gov (United States)

    Yang, Yiqun; Jankowiak, Ryszard; Lin, Chen; Pawlak, Krzysztof; Reus, Michael; Holzwarth, Alfred R; Li, Jun

    2014-10-14

    A modified dye-sensitized solar cell consisting of a thin TiO2 barrier layer sensitized with natural trimeric light-harvesting complex II (LHCII) from spinach was used as a biomimetic model to study the effects of LHCII aggregation on the photovoltaic properties. The aggregation of individual trimers induced molecular reorganization, which dramatically increased the photocurrent. The morphology of small- and large-size LHCII aggregates deposited on a surface was confirmed by atomic force microscopy. Enhanced LHCII immobilization was accomplished via electrostatic interaction with amine-functionalized photoanodes. The photocurrent responses of the assembled solar cells under illumination at three characteristic wavelength bands in the UV-Vis absorption spectra of LHCII solutions confirmed that a significant photocurrent was generated by LHCII photosensitizers. The enhanced photocurrent by large aggregated LHCII is shown to correlate with the quenching in the far-red fluorescence deriving from chlorophyll-chlorophyll charge transfer states that are effectively coupled with the TiO2 surface and thus inject electrons into the TiO2 conduction band. The large aggregated LHCII with more chlorophyll-chlorophyll charge transfer states is a much better sensitizer since it injects electrons more efficiently into the conduction band of TiO2 than the small aggregated LHCII mostly consisting of unquenched chlorophyll excited state. The assembled solar cells demonstrated remarkable stability in both aqueous buffer and acetonitrile electrolytes over 30 days.

  1. Aggregation of Organic Semiconductors and Its Influence on Carrier Transport and Solar Cell Performance

    KAUST Repository

    Hu, Hanlin

    2017-08-28

    Photovoltaic technology based on solution-processable organic solar cells (OSCs) provides a promising route towards a low-cost strategy to address the sharply increasing energy demands worldwide. However, up to date, the vast majority of solar cell reports have been based on spin-cast BHJ layers. Spin coating is not compatible with high speed and scalable coating processes, such as blade-coating and slot-die coating, which require the nanoscale morphology to be reproduced in scalable coating methods. And tolerance for thicker BHJ films would also facilitate high speed scalable coating. In the first part of this thesis, we investigate how pre-aggregating the conjugated polymer in solution impacts the charge transport in polymer films. We use P3HT in a wide range of molecular weights in different solvents of common use in organic electronics to investigate how they impact the aggregation behavior in the ink and in the solid state. By deliberately disentangling polymer chains via sonication of the solution in the presence of solvophobic driving forces, we show a remarkable ability to tune aggregation, which directly impacts charge transport, as measured in the context of field effect transistors. The second part of this thesis looks at the impact of the solution-coating method and the photovoltaic performance gap when applying modern BHJ inks developed for spin coating to scalable coating methods, namely blade coating. We ascribe this to significant differences in the drying kinetics between the processes. Emulating the drying kinetics of spin-coating was found to result in performance parity as well as morphological parity across several systems, resulting in demonstration of PTB7:PC71BM solar cells with efficiency of 9% and 6.5% PCEs on glass and flexible PET substrates, respectively. The last part of this thesis looks into going beyond performance parity by leveraging the differences of the scalable coating method to enable highly efficient thick solar cells which

  2. Multiscale modeling of bacterial colonies: how pili mediate the dynamics of single cells and cellular aggregates

    Science.gov (United States)

    Pönisch, Wolfram; Weber, Christoph A.; Juckeland, Guido; Biais, Nicolas; Zaburdaev, Vasily

    2017-01-01

    Neisseria gonorrhoeae is the causative agent of one of the most common sexually transmitted diseases, gonorrhea. Over the past two decades there has been an alarming increase of reported gonorrhea cases where the bacteria were resistant to the most commonly used antibiotics thus prompting for alternative antimicrobial treatment strategies. The crucial step in this and many other bacterial infections is the formation of microcolonies, agglomerates consisting of up to several thousands of cells. The attachment and motility of cells on solid substrates as well as the cell-cell interactions are primarily mediated by type IV pili, long polymeric filaments protruding from the surface of cells. While the crucial role of pili in the assembly of microcolonies has been well recognized, the exact mechanisms of how they govern the formation and dynamics of microcolonies are still poorly understood. Here, we present a computational model of individual cells with explicit pili dynamics, force generation and pili-pili interactions. We employ the model to study a wide range of biological processes, such as the motility of individual cells on a surface, the heterogeneous cell motility within the large cell aggregates, and the merging dynamics and the self-assembly of microcolonies. The results of numerical simulations highlight the central role of pili generated forces in the formation of bacterial colonies and are in agreement with the available experimental observations. The model can quantify the behavior of multicellular bacterial colonies on biologically relevant temporal and spatial scales and can be easily adjusted to include the geometry and pili characteristics of various bacterial species. Ultimately, the combination of the microbiological experimental approach with the in silico model of bacterial colonies might provide new qualitative and quantitative insights on the development of bacterial infections and thus pave the way to new antimicrobial treatments.

  3. Effects of simvastatin/ezetimibe on microparticles, endothelial progenitor cells and platelet aggregation in subjects with coronary heart disease under antiplatelet therapy

    Energy Technology Data Exchange (ETDEWEB)

    Camargo, L.M.; França, C.N.; Izar, M.C.; Bianco, H.T.; Lins, L.S.; Barbosa, S.P.; Pinheiro, L.F.; Fonseca, F.A.H. [Universidade Federal de São Paulo, Escola Paulista de Medicina, Departamento de Medicina, São Paulo, SP, Brasil, Departamento de Medicina, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, SP (Brazil)

    2014-04-15

    It is not known whether the addition of ezetimibe to statins adds cardiovascular protection beyond the expected changes in lipid levels. Subjects with coronary heart disease were treated with four consecutive 1-week courses of therapy (T) and evaluations. The courses were: T1, 100 mg aspirin alone; T2, 100 mg aspirin and 40 mg simvastatin/10 mg ezetimibe; T3, 40 mg simvastatin/10 mg ezetimibe, and 75 mg clopidogrel (300 mg initial loading dose); T4, 75 mg clopidogrel alone. Platelet aggregation was examined in whole blood. Endothelial microparticles (CD51), platelet microparticles (CD42/CD31), and endothelial progenitor cells (CD34/CD133; CDKDR/CD133, or CD34/KDR) were quantified by flow cytometry. Endothelial function was examined by flow-mediated dilation. Comparisons between therapies revealed differences in lipids (T2 and T3T1 and T4, P=0.001). Decreased platelet aggregation was observed after aspirin (arachidonic acid, T1aggregation, the amount of circulating endothelial and platelet microparticles, or endothelial progenitor cells. Cardiovascular protection following therapy with simvastatin/ezetimibe seems restricted to lipid changes and improvement of endothelial function not affecting the release of microparticles, mobilization of endothelial progenitor cells or decreased platelet aggregation.

  4. Effects of simvastatin/ezetimibe on microparticles, endothelial progenitor cells and platelet aggregation in subjects with coronary heart disease under antiplatelet therapy

    International Nuclear Information System (INIS)

    Camargo, L.M.; França, C.N.; Izar, M.C.; Bianco, H.T.; Lins, L.S.; Barbosa, S.P.; Pinheiro, L.F.; Fonseca, F.A.H.

    2014-01-01

    It is not known whether the addition of ezetimibe to statins adds cardiovascular protection beyond the expected changes in lipid levels. Subjects with coronary heart disease were treated with four consecutive 1-week courses of therapy (T) and evaluations. The courses were: T1, 100 mg aspirin alone; T2, 100 mg aspirin and 40 mg simvastatin/10 mg ezetimibe; T3, 40 mg simvastatin/10 mg ezetimibe, and 75 mg clopidogrel (300 mg initial loading dose); T4, 75 mg clopidogrel alone. Platelet aggregation was examined in whole blood. Endothelial microparticles (CD51), platelet microparticles (CD42/CD31), and endothelial progenitor cells (CD34/CD133; CDKDR/CD133, or CD34/KDR) were quantified by flow cytometry. Endothelial function was examined by flow-mediated dilation. Comparisons between therapies revealed differences in lipids (T2 and T3T1 and T4, P=0.001). Decreased platelet aggregation was observed after aspirin (arachidonic acid, T1aggregation, the amount of circulating endothelial and platelet microparticles, or endothelial progenitor cells. Cardiovascular protection following therapy with simvastatin/ezetimibe seems restricted to lipid changes and improvement of endothelial function not affecting the release of microparticles, mobilization of endothelial progenitor cells or decreased platelet aggregation

  5. 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...

  6. The in vitro biokinetics of chlorpromazine and diazepam in aggregating rat brain cell cultures after repeated exposure

    NARCIS (Netherlands)

    Broeders, Jessica J W; Hermens, Joop L M; Blaauboer, Bas J; Zurich, Marie-Gabrielle

    2015-01-01

    Neurotoxic effects of compounds can be tested in vitro using cell systems. One example is aggregating rat brain cell cultures. For the extrapolation of in vitro data to the in vivo situation, it is important to take the biokinetics of the test compound into account. In addition, the exposure in vivo

  7. Aggregative adherent strains of Corynebacterium pseudodiphtheriticum enter and survive within HEp-2 epithelial cells

    Directory of Open Access Journals (Sweden)

    Monica Cristina de Souza

    2012-06-01

    Full Text Available Corynebacterium pseudodiphtheriticum is a well-known human pathogen that mainly causes respiratory disease and is associated with high mortality in compromised hosts. Little is known about the virulence factors and pathogenesis of C. pseudodiphtheriticum. In this study, cultured human epithelial (HEp-2 cells were used to analyse the adherence pattern, internalisation and intracellular survival of the ATCC 10700 type strain and two additional clinical isolates. These microorganisms exhibited an aggregative adherence-like pattern to HEp-2 cells characterised by clumps of bacteria with a "stacked-brick" appearance. The differences in the ability of these microorganisms to invade and survive within HEp-2 cells and replicate in the extracellular environment up to 24 h post infection were evaluated. The fluorescent actin staining test demonstrated that actin polymerisation is involved in the internalisation of the C. pseudodiphtheriticum strains. The depolymerisation of microfilaments by cytochalasin E significantly reduced the internalisation of C. pseudodiphtheriticum by HEp-2 cells. Bacterial internalisation and cytoskeletal rearrangement seemed to be partially triggered by the activation of tyrosine kinase activity. Although C. pseudodiphtheriticum strains did not demonstrate an ability to replicate intracellularly, HEp-2 cells were unable to fully clear the pathogen within 24 h. These characteristics may explain how some C. pseudodiphtheriticum strains cause severe infection in human patients.

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

    Science.gov (United States)

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

    2011-10-01

    The mechanisms of red blood cell (RBC) deformation under both static and dynamic, i.e., flow, conditions have been studied extensively since the mid 1960s. Deformation-induced biochemical reactions and possible signaling in RBCs, however, were proposed only fifteen years ago. Therefore, the fundamental relationship between RBC deformation and cellular signaling dynamics i.e., mechanotransduction, remains incompletely understood. Quantitative understanding of the mechanotransductive pathways in RBCs requires integrative studies of physical models of RBC deformation and cellular biochemical reactions. In this article we review the physical models of RBC deformation, spanning from continuum membrane mechanics to cellular skeleton dynamics under both static and flow conditions, and elaborate the mechanistic links involved in deformation-induced ATP release. This journal is © The Royal Society of Chemistry 2011

  9. Generation of Aggregates of Mouse Embryonic Stem Cells that Show Symmetry Breaking, Polarization and Emergent Collective Behaviour In Vitro.

    Science.gov (United States)

    Baillie-Johnson, Peter; van den Brink, Susanne Carina; Balayo, Tina; Turner, David Andrew; Martinez Arias, Alfonso

    2015-11-24

    We have developed a protocol improving current Embryoid Body (EB) culture which allows the study of self-organization, symmetry breaking, axial elongation and cell fate specification using aggregates of mouse embryonic stem cells (mESCs) in suspension culture. Small numbers of mESCs are aggregated in basal medium for 48 hr in non-tissue-culture-treated, U-bottomed 96-well plates, after which they are competent to respond to experimental signals. Following treatment, these aggregates begin to show signs of polarized gene expression and gradually alter their morphology from a spherical mass of cells to an elongated, well organized structure in the absence of external asymmetry cues. These structures are not only able to display markers of the three germ layers, but actively display gastrulation-like movements, evidenced by a directional dislodgement of individual cells from the aggregate, which crucially occurs at one region of the elongated structure. This protocol provides a detailed method for the reproducible formation of these aggregates, their stimulation with signals such as Wnt/β-Catenin activation and BMP inhibition and their analysis by single time-point or time-lapse fluorescent microscopy. In addition, we describe modifications to current whole-mount mouse embryo staining procedures for immunocytochemical analysis of specific markers within fixed aggregates. The changes in morphology, gene expression and length of the aggregates can be quantitatively measured, providing information on how signals can alter axial fates. It is envisaged that this system can be applied both to the study of early developmental events such as axial development and organization, and more broadly, the processes of self-organization and cellular decision-making. It may also provide a suitable niche for the generation of cell types present in the embryo that are unobtainable from conventional adherent culture such as spinal cord and motor neurones.

  10. 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 ...

  11. 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.

  12. 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.

  13. A 3D Culture Model to Study How Fluid Pressure and Flow Affect the Behavior of Aggregates of Epithelial Cells.

    Science.gov (United States)

    Piotrowski-Daspit, Alexandra S; Simi, Allison K; Pang, Mei-Fong; Tien, Joe; Nelson, Celeste M

    2017-01-01

    Cells are surrounded by mechanical stimuli in their microenvironment. It is important to determine how cells respond to the mechanical information that surrounds them in order to understand both development and disease progression, as well as to be able to predict cell behavior in response to physical stimuli. Here we describe a protocol to determine the effects of interstitial fluid flow on the migratory behavior of an aggregate of epithelial cells in a three-dimensional (3D) culture model. This protocol includes detailed methods for the fabrication of a 3D cell culture chamber with hydrostatic pressure control, the culture of epithelial cells as an aggregate in a collagen gel, and the analysis of collective cell behavior in response to pressure-driven flow.

  14. Freeze-Dried Human Red Blood Cells

    Science.gov (United States)

    1992-04-15

    period in the liquid state. 2. The levels of glycolytic intermediates (ATP, adenosine 5’triphosphate; 2,3-DPG 2, 3- diphosphoglycerate ) in rehydrated...8217 diphosphate, ADP; adenosine 5 monophosphate, AMP; 2,3- diphosphoglycerate . 2.3-DPG and lactate: (2) measurement of cell indices (mean cell volume (MCV), mean...monophosphate: 2,3-DPG. 2.3- diphosphoglycerate : MCV. Mean Cell Volume: MCH, Mean Cell Hemoglobin: MCHC, Mean Cell Hemoglobin Concentrations. ** Lactate levels

  15. 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...

  16. The common inhaled anesthetic isoflurane increases aggregation of huntingtin and alters calcium homeostasis in a cell model of Huntington's disease

    International Nuclear Information System (INIS)

    Wang Qiujun; Liang Ge; Yang Hui; Wang Shouping; Eckenhoff, Maryellen F.; Wei Huafeng

    2011-01-01

    Isoflurane is known to increase β-amyloid aggregation and neuronal damage. We hypothesized that isoflurane will have similar effects on the polyglutamine huntingtin protein and will cause alterations in intracellular calcium homeostasis. We tested this hypothesis in striatal cells from the expanded glutamine huntingtin knock-in mouse (STHdh Q111/Q111 ) and wild type (STHdh Q7/Q7 ) striatal neurons. The primary cultured neurons were exposed for 24 h to equipotent concentrations of isoflurane, sevoflurane, and desflurane in the presence or absence of extracellular calcium and with or without xestospongin C, a potent endoplasmic reticulum inositol 1,4,5-trisphosphate (InsP 3 ) receptor antagonist. Aggregation of huntingtin protein, cell viability, and calcium concentrations were measured. Isoflurane, sevoflurane, and desflurane all increased the aggregation of huntingtin in STHdh Q111/Q111 cells, with isoflurane having the largest effect. Isoflurane induced greater calcium release from the ER and relatively more cell damage in the STHdh Q111/Q111 huntingtin cells than in the wild type STHdh Q7/Q7 striatal cells. However, sevoflurane and desflurane caused less calcium release from the ER and less cell damage. Xestospongin C inhibited the isoflurane-induced calcium release from the ER, aggregation of huntingtin, and cell damage in the STHdh Q111/Q111 cells. In summary, the Q111 form of huntingtin increases the vulnerability of striatal neurons to isoflurane neurotoxicity through combined actions on the ER IP 3 receptors. Calcium release from the ER contributes to the anesthetic induced huntingtin aggregation in STHdh Q111/Q111 striatal cells.

  17. Effects of agitation rate on aggregation during beads-to-beads subcultivation of microcarrier culture of human mesenchymal stem cells.

    Science.gov (United States)

    Takahashi, Iori; Sato, Keigo; Mera, Hisashi; Wakitani, Shigeyuki; Takagi, Mutsumi

    2017-06-01

    With the aim to utilize human mesenchymal stem cells (hMSCs) grown in large scale for regenerative medicine, effects of agitation rate on aggregation during beads-to-beads subcultivation of microcarrier culture of hMSCs were studied. hMSCs could attach and grew on surface-type microcarriers of Cytodex 1, whereas almost no cell elongation and growth were observed on porous type microcarriers of Cytopores. The percentages of aggregated Cytodex 1 microcarriers at an agitation rate of 60 and 90 rpm were lower than that at 30 rpm, which was the lowest agitation rate necessary for the suspension of Cytodex 1 microcarriers, and the cells grew fastest at 60 rpm. hMSC could be subcultivated on Cytodex 1 by the beads-to-beads method at both 30 and 60 rpm without trypsinization. However, agitation at 60 rpm resulted in a markedly lower percentage of aggregated microcarriers not only before but also after subcultivation. The percentages of CD90- and CD166-positive cells among cells grown on Cytodex 1 at 60 rpm (91.5 and 87.6 %) were comparable to those of cells grown in the pre-culture on dishes. In conclusion, hMSCs could be subcultivated on Cytodex 1 by beads-to-beads method maintaining the expressions of the cell surface antigens CD90 and CD166, while adjusting agitation rate could decrease the microcarrier aggregation.

  18. Aqueous Extract of Paeonia lactiflora and Paeoniflorin as Aggregation Reducers Targeting Chaperones in Cell Models of Spinocerebellar Ataxia 3

    Directory of Open Access Journals (Sweden)

    Kuo-Hsuan Chang

    2013-01-01

    Full Text Available Spinocerebellar ataxia (SCA types 1, 2, 3, 6, 7, and 17 as well as Huntington’s disease are a group of neurodegenerative disorders caused by expanded CAG repeats encoding a long polyglutamine (polyQ tract in the respective proteins. Evidence has shown that the accumulation of intranuclear and cytoplasmic misfolded polyQ proteins leads to apoptosis and cell death. Thus suppression of aggregate formation is expected to inhibit a wide range of downstream pathogenic events in polyQ diseases. In this study, we established a high-throughput aggregation screening system using 293 ATXN3/Q75-GFP cells and applied this system to test the aqueous extract of Paeonia lactiflora (P. lactiflora and its constituents. We found that the aggregation can be significantly prohibited by P. lactiflora and its active compound paeoniflorin. Meanwhile, P. lactiflora and paeoniflorin upregulated HSF1 and HSP70 chaperones in the same cell models. Both of them further reduced the aggregation in neuronal differentiated SH-SY5Y ATXN3/Q75-GFP cells. Our results demonstrate how P. lactiflora and paeoniflorin are likely to work on polyQ-aggregation reduction and provide insight into the possible working mechanism of P. lactiflora in SCA3. We anticipate our paper to be a starting point for screening more potential herbs for the treatment of SCA3 and other polyQ diseases.

  19. Brain Aggregates: An Effective In Vitro Cell Culture System Modeling Neurodegenerative Diseases.

    Science.gov (United States)

    Ahn, Misol; Kalume, Franck; Pitstick, Rose; Oehler, Abby; Carlson, George; DeArmond, Stephen J

    2016-03-01

    Drug discovery for neurodegenerative diseases is particularly challenging because of the discrepancies in drug effects between in vitro and in vivo studies. These discrepancies occur in part because current cell culture systems used for drug screening have many limitations. First, few cell culture systems accurately model human aging or neurodegenerative diseases. Second, drug efficacy may differ between dividing and stationary cells, the latter resembling nondividing neurons in the CNS. Brain aggregates (BrnAggs) derived from embryonic day 15 gestation mouse embryos may represent neuropathogenic processes in prion disease and reflect in vivo drug efficacy. Here, we report a new method for the production of BrnAggs suitable for drug screening and suggest that BrnAggs can model additional neurological diseases such as tauopathies. We also report a functional assay with BrnAggs by measuring electrophysiological activities. Our data suggest that BrnAggs could serve as an effective in vitro cell culture system for drug discovery for neurodegenerative diseases. © 2016 American Association of Neuropathologists, Inc. All rights reserved.

  20. Effect of mineral trioxide aggregates and Portland cements on inflammatory cells.

    Science.gov (United States)

    Shahi, Shahriar; Rahimi, Saeed; Yavari, Hamid Reza; Mokhtari, Hadi; Roshangar, Leila; Abasi, Mehran Mesgary; Sattari, Sahar; Abdolrahimi, Majid

    2010-05-01

    Recently, some studies have compared mineral trioxide aggregate (MTA) with Portland cements, concluding that the principal ingredients of Portland cements are similar to those of MTA. The purpose of the present study was to evaluate the effect of gray MTA, white MTA, and gray and white Portland cements on inflammatory cells in rats. Fresh mixtures mixed with distilled water were placed in polyethylene tubes, which were implanted in the dorsal subcutaneous connective tissue of 60 Sprague-Dawley rats along with empty tubes as controls. Tissue specimens were collected after the rats were sacrificed after 7, 15, 30, 60, and 90 days. The specimens were fixed, stained, processed, and histologically evaluated under a light microscope. Inflammatory reactions were classified as grade 0: without inflammatory cells, grade I: sporadic infiltration of inflammatory cells, grade II: moderate infiltration (125 cells). Data were analyzed with the nonparametric (two factor) analysis of variance and Kruskal-Wallis H-test. All the groups showed grade III inflammation after 7 and 15 days; there was a decrease in the inflammatory process after 30, 60, and 90 days. After 90 days, gray MTA, white MTA, and control groups had grade 0 inflammatory process, but gray Portland cement and white Portland cement groups showed grade 0 to grade I inflammatory processes. MTAs were more biocompatible; however, more studies are required. Copyright (c) 2010 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  1. 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...

  2. 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 ...

  3. 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 ...

  4. 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

  5. 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...

  6. Retrofit designs for small bench-type blood cell counters.

    Science.gov (United States)

    Ferris, C D

    1991-01-01

    This paper describes several retrofit designs to correct operational problems associated with small bench-type blood cell counters. Replacement electronic circuits as well as modifications to the vacuum systems are discussed.

  7. 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.

  8. 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.

  9. 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.

  10. Porphyrin Dye-Sensitized Zinc Oxide Aggregated Anodes for Use in Solar Cells

    Directory of Open Access Journals (Sweden)

    Yu-Kai Syu

    2016-08-01

    Full Text Available Porphyrin YD2-o-C8-based dyes were employed to sensitize room-temperature (RT chemical-assembled ZnO aggregated anodes for use in dye-sensitized solar cells (DSSCs. To reduce the acidity of the YD2-o-C8 dye solution, the proton in the carboxyl group of a porphyrin dye was replaced with tetrabuthyl ammonium (TBA+ in this work. The short-circuit current density (Jsc of the YD2-o-C8-TBA-sensitized ZnO DSSCs is higher than that of the YD2-o-C8-sensitized cells, resulting in the improvement of the efficiency of the YD2-o-C8-based ZnO DSSCs. With an appropriate incorporation of chenodeoxycholic acid (CDCA as coadsorbate, the Jsc and efficiency of the YD2-o-C8-TBA-sensitized ZnO DSSC are enhanced due to the improvement of the incident-photon-to-current efficiency (IPCE values in the wavelength range of 400–450 nm. Moreover, a considerable increase in Jsc is achieved by the addition of a light scattering layer in the YD2-o-C8-TBA-sensitized ZnO photoanodes. Significant IPCE enhancement in the range 475–600 nm is not attainable by tuning the YD2-o-C8-TBA sensitization processes for the anodes without light scattering layers. Using the RT chemical-assembled ZnO aggregated anode with a light scattering layer, an efficiency of 3.43% was achieved in the YD2-o-C8-TBA-sensitized ZnO DSSC.

  11. Formation of model hepatocellular aggregates in a hydrogel scaffold using degradable genipin crosslinked gelatin microspheres as cell carriers

    International Nuclear Information System (INIS)

    Lau, Ting Ting; Lee, Li Qi Priscilyn; Leong, Wenyan; Wang, Dong-An

    2012-01-01

    Primary hepatocyte is probably the preferred cell for cell therapy in liver regeneration. However, its non-ideal proliferation capacity and rapid loss of phenotype during 2D culture compromises the quality and quantity of the transplanted hepatocytes, resulting in variable success rates of this treatment. Many studies have shown that the formation of 3D hepatocellular spheroids aids in the maintenance of liver-specific functions in hepatocytes. However, many of the methodologies employed require a sophisticated set-up or specialized equipment which makes it uneconomical to scale up for clinical applications. In this study, we have developed dual-functioning genipin crosslinked gelatin microspheres that serve as cell carriers as well as porogens for delivering the model cells and also for creating cavities. The cells were first seeded onto genipin crosslinked gelatin microspheres for attachment, followed by encapsulation in alginate hydrogel. Collagenase, MMP-9, was introduced either in the culture media or mixed with alginate precursor solution to allow microsphere degradation for creating cavities within the gel bulk. Accordingly, the cells proliferate within the cavities, forming hepatocellular aggregates while the alginate hydrogel serves as a confinement, restricting the size and the shape of the aggregates to the size of the cavities. In addition, the final hepatocellular aggregates could be harvested from the system by removing the alginate hydrogel via citrate treatment. Therefore, this versatile platform not only has the advantage of injectability and simplicity, the cellular aggregates generated are in a controlled size and shape and can be extracted from the system. (paper)

  12. Generation of Human Induced Pluripotent Stem Cells from Peripheral Blood Mononuclear Cells Using Sendai Virus.

    Science.gov (United States)

    Soares, Filipa A C; Pedersen, Roger A; Vallier, Ludovic

    2016-01-01

    This protocol describes the efficient isolation of peripheral blood mononuclear cells from circulating blood via density gradient centrifugation and subsequent generation of integration-free human induced pluripotent stem cells. Peripheral blood mononuclear cells are cultured for 9 days to allow expansion of the erythroblast population. The erythroblasts are then used to derive human induced pluripotent stem cells using Sendai viral vectors, each expressing one of the four reprogramming factors Oct4, Sox2, Klf4, and c-Myc.

  13. Red Blood Cell Agglutination for Blood Typing Within Passive Microfluidic Biochips.

    Science.gov (United States)

    Huet, Maxime; Cubizolles, Myriam; Buhot, Arnaud

    2018-04-19

    Pre-transfusion bedside compatibility test is mandatory to check that the donor and the recipient present compatible groups before any transfusion is performed. Although blood typing devices are present on the market, they still suffer from various drawbacks, like results that are based on naked-eye observation or difficulties in blood handling and process automation. In this study, we addressed the development of a red blood cells (RBC) agglutination assay for point-of-care blood typing. An injection molded microfluidic chip that is designed to enhance capillary flow contained anti-A or anti-B dried reagents inside its microchannel. The only blood handling step in the assay protocol consisted in the deposit of a blood drop at the tip of the biochip, and imaging was then achieved. The embedded reagents were able to trigger RBC agglutination in situ, allowing for us to monitor in real time the whole process. An image processing algorithm was developed on diluted bloods to compute real-time agglutination indicator and was further validated on undiluted blood. Through this proof of concept, we achieved efficient, automated, real time, and quantitative measurement of agglutination inside a passive biochip for blood typing which could be further generalized to blood biomarker detection and quantification.

  14. Embryo aggregation does not improve the development of interspecies somatic cell nuclear transfer embryos in the horse.

    Science.gov (United States)

    Gambini, Andrés; De Stéfano, Adrián; Jarazo, Javier; Buemo, Carla; Karlanian, Florencia; Salamone, Daniel Felipe

    2016-09-01

    The low efficiency of interspecies somatic cell nuclear transfer (iSCNT) makes it necessary to investigate new strategies to improve embryonic developmental competence. Embryo aggregation has been successfully applied to improve cloning efficiency in mammals, but it remains unclear whether it could also be beneficial for iSCNT. In this study, we first compared the effect of embryo aggregation over in vitro development and blastocyst quality of porcine, bovine, and feline zona-free (ZF) parthenogenetic (PA) embryos to test the effects of embryo aggregation on species that were later used as enucleated oocytes donors in our iSCNT study. We then assessed whether embryo aggregation could improve the in vitro development of ZF equine iSCNT embryos after reconstruction with porcine, bovine, and feline ooplasm. Bovine- and porcine-aggregated PA blastocysts had significantly larger diameters compared with nonaggregated embryos. On the other hand, feline- and bovine-aggregated PA embryos had higher blastocyst cell number. Embryo aggregation of equine-equine SCNT was found to be beneficial for embryo development as we have previously reported, but the aggregation of three ZF reconstructed embryos did not improve embryo developmental rates on iSCNT. In vitro embryo development of nonaggregated iSCNT was predominantly arrested around the stage when transcriptional activation of the embryonic genome is reported to start on the embryo of the donor species. Nevertheless, independent of embryo aggregation, equine blastocyst-like structures could be obtained in our study using domestic feline-enucleated oocytes. Taken together, these results reported that embryo aggregation enhance in vitro PA embryo development and embryo quality but effects vary depending on the species. Embryo aggregation also improves, as expected, the in vitro embryo development of equine-equine SCNT embryos; however, we did not observe positive effects on equine iSCNT embryo development. Among oocytes

  15. SBR-Blood: systems biology repository for hematopoietic cells.

    Science.gov (United States)

    Lichtenberg, Jens; Heuston, Elisabeth F; Mishra, Tejaswini; Keller, Cheryl A; Hardison, Ross C; Bodine, David M

    2016-01-04

    Extensive research into hematopoiesis (the development of blood cells) over several decades has generated large sets of expression and epigenetic profiles in multiple human and mouse blood cell types. However, there is no single location to analyze how gene regulatory processes lead to different mature blood cells. We have developed a new database framework called hematopoietic Systems Biology Repository (SBR-Blood), available online at http://sbrblood.nhgri.nih.gov, which allows user-initiated analyses for cell type correlations or gene-specific behavior during differentiation using publicly available datasets for array- and sequencing-based platforms from mouse hematopoietic cells. SBR-Blood organizes information by both cell identity and by hematopoietic lineage. The validity and usability of SBR-Blood has been established through the reproduction of workflows relevant to expression data, DNA methylation, histone modifications and transcription factor occupancy profiles. Published by Oxford University Press on behalf of Nucleic Acids Research 2015. This work is written by (a) US Government employee(s) and is in the public domain in the US.

  16. Weak glycolipid binding of a microdomain-tracer peptide correlates with aggregation and slow diffusion on cell membranes.

    Directory of Open Access Journals (Sweden)

    Tim Lauterbach

    Full Text Available Organized assembly or aggregation of sphingolipid-binding ligands, such as certain toxins and pathogens, has been suggested to increase binding affinity of the ligand to the cell membrane and cause membrane reorganization or distortion. Here we show that the diffusion behavior of the fluorescently tagged sphingolipid-interacting peptide probe SBD (Sphingolipid Binding Domain is altered by modifications in the construction of the peptide sequence that both result in a reduction in binding to ganglioside-containing supported lipid membranes, and at the same time increase aggregation on the cell plasma membrane, but that do not change relative amounts of secondary structural features. We tested the effects of modifying the overall charge and construction of the SBD probe on its binding and diffusion behavior, by Surface Plasmon Resonance (SPR; Biacore analysis on lipid surfaces, and by Fluorescence Correlation Spectroscopy (FCS on live cells, respectively. SBD binds preferentially to membranes containing the highly sialylated gangliosides GT1b and GD1a. However, simple charge interactions of the peptide with the negative ganglioside do not appear to be a critical determinant of binding. Rather, an aggregation-suppressing amino acid composition and linker between the fluorophore and the peptide are required for optimum binding of the SBD to ganglioside-containing supported lipid bilayer surfaces, as well as for interaction with the membrane. Interestingly, the strength of interactions with ganglioside-containing artificial membranes is mirrored in the diffusion behavior by FCS on cell membranes, with stronger binders displaying similar characteristic diffusion profiles. Our findings indicate that for aggregation-prone peptides, aggregation occurs upon contact with the cell membrane, and rather than giving a stronger interaction with the membrane, aggregation is accompanied by weaker binding and complex diffusion profiles indicative of heterogeneous

  17. 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.

  18. 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.

  19. 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)

  20. 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

  1. The effect of centrifugation at various g force levels on rheological properties of rat, dog, pig and human red blood cells.

    Science.gov (United States)

    Kiss, Ferenc; Toth, Eniko; Miszti-Blasius, Kornel; Nemeth, Norbert

    2016-01-01

    Laboratory investigations often require centrifugation of blood samples for various erythrocyte tests. Although there is a lack of data about the effect of centrifugation at various g force levels on erythrocyte rheological properties. We aimed to investigate the effect of a 10-minute centrifugation at 500, 1000 or 1500 g at 15°C of rat, dog, pig and human venous (K3-EDTA, 1.5 mg/ml) blood samples. Hematological parameters, erythrocyte deformability, cell membrane stability, osmotic gradient ektacytometry (osmoscan) and erythrocyte aggregation were determined. Hematological and erythrocyte deformability parameters showed interspecies differences, centrifugation caused no significant alterations. Cell membrane stability for human erythrocytes centrifuged at higher g level showed less decrease in deformability. Osmoscan O min parameter showed slight elevation in dog centrifuged aliquots. Erythrocyte aggregation parameters changed unexpectedly. Rat and dog erythrocyte aggregation indices significantly dropped in centrifuged aliquots. Pig erythrocyte aggregation indices increased significantly after centrifugation. Human erythrocyte aggregation was the most stable one among the investigated species. The used centrifugation protocols caused the largest alterations in erythrocyte aggregation in a controversial way among the investigated species. On the other hand, erythrocyte deformability parameters were stable, cell membrane stability and osmoscan data show minor shifts.

  2. CD147 and CD98 complex-mediated homotypic aggregation attenuates the CypA-induced chemotactic effect on Jurkat T cells.

    Science.gov (United States)

    Guo, Na; Zhang, Kui; Lv, Minghua; Miao, Jinlin; Chen, Zhinan; Zhu, Ping

    2015-02-01

    Homotypic cell aggregation plays important roles in physiological and pathological processes, including embryogenesis, immune responses, angiogenesis, tumor cell invasion and metastasis. CD147 has been implicated in most of these phenomena, and it was identified as a T cell activation-associated antigen due to its obvious up-regulation in activated T cells. However, the explicit function and mechanism of CD147 in T cells have not been fully elucidated. In this study, large and compact aggregates were observed in Jurkat T cells after treatment with the specific CD147 monoclonal antibody HAb18 or after the expression of CD147 was silenced by RNA interference, which indicated an inhibitory effect of CD147 in T cell homotypic aggregation. Knocking down CD147 expression resulted in a significant decrease in CD98, along with prominent cell aggregation, similar to that treated by CD98 and CD147 monoclonal antibodies. Furthermore, decreased cell chemotactic activity was observed following CD147- and CD98-mediated cell aggregation, and increased aggregation was correlated with a decrease in the chemotactic ability of the Jurkat T cells, suggesting that CD147- and CD98-mediated homotypic cell aggregation plays a negative role in T cell chemotaxis. Our data also showed that p-ERK, p-ZAP70, p-CD3ζ and p-LCK were significantly decreased in the CD147- and CD98-knocked down Jurkat T cells, which suggested that decreased CD147- and/or CD98-induced homotypic T cell aggregation and aggregation-inhibited chemotaxis might be associated with these signaling pathways. A role for CD147 in cell aggregation and chemotaxis was further indicated in primary CD4(+) T cells. Similarly, low expression of CD147 in primary T cells induced prominent cell aggregation and this aggregation attenuated primary T cell chemotactic ability in response to CypA. Our results have demonstrated the correlation between homotypic cell aggregation and the chemotactic response of T cells to CypA, and these data

  3. Tissue-specific composite cell aggregates drive periodontium tissue regeneration by reconstructing a regenerative microenvironment.

    Science.gov (United States)

    Zhu, Bin; Liu, Wenjia; Zhang, Hao; Zhao, Xicong; Duan, Yan; Li, Dehua; Jin, Yan

    2017-06-01

    Periodontitis is the most common cause of periodontium destruction. Regeneration of damaged tissue is the expected treatment goal. However, the regeneration of a functional periodontal ligament (PDL) insertion remains a difficulty, due to complicated factors. Recently, periodontal ligament stem cells (PDLSCs) and bone marrow-derived mesenchymal stem cells (BMMSCs) have been shown to participate in PDL regeneration, both pathologically and physiologically. Besides, interactions affect the biofunctions of different derived cells during the regenerative process. Therefore, the purpose of this study was to discuss the different derived composite cell aggregate (CA) systems of PDLSCs and BMMSCs (iliac-derived or jaw-derived) for periodontium regeneration under regenerative microenvironment reconstruction. Our results showed although all three mono-MSC CAs were compacted and the cells arranged regularly in them, jaw-derived BMMSC (JBMMSC) CAs secreted more extracellular matrix than the others. Furthermore, PDLSC/JBMMSC compound CAs highly expressed ALP, Col-I, fibronectin, integrin-β1 and periostin, suggesting that their biofunction is more appropriate for periodontal structure regeneration. Inspiringly, PDLSC/JBMMSC compound CAs regenerated more functional PDL-like tissue insertions in both nude mice ectopic and minipig orthotopic transplantation. The results indicated that the different derived CAs of PDLSCs/JBMMSCs provided an appropriate regenerative microenvironment facilitating a more stable and regular regeneration of functional periodontium tissue. This method may provide a possible strategy to solve periodontium defects in periodontitis and powerful experimental evidence for clinical applications in the future. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

  4. Blood cell labeling with technetium-99m, (2)

    International Nuclear Information System (INIS)

    Uchida, Tatsumi; Yoshida, Hiroshi; Matsuda, Shin; Kimura, Hideo; Miura, Nobuo

    1978-01-01

    Using a labeling method with sup(99m)Tc-pertechnetate to red blood cells (RBC), circulating blood volume was measured in comparison with that from 51 Cr-labeled RBC method. The technique is easier than already published methods, because CIS kit for sup(99m)Tc-RBC labeling (TCK-11) became to be available recently. Two mls of ACD-anticoagulated blood were withdrawn and 0.5 ml of reducing reagent prepared just before use was added to blood, waiting 5 minutes and discarding the serum after centrifugation, then adding 100 μCi of sup(99m)Tc. After washing the labeled cells by isotonic saline, cells were re-suspended in 10 ml of saline and injected to the subject. Blood specimen was obtained 10, 30, 60 and 120 minutes after infusion and blood volume was calculated by the usual way. Circulating blood volume by sup(99m)Tc was well correlated with that by 51 Cr (=0.98, p 0.01), however, the value calculated from sup(99m)Tc were 4.8 percent higher than those by 51 Cr, which suggested the elution of sup(99m)Tc from labeled RBC. sup(99m)Tc method has the advantages that higher radioactivity can be obtained in small amount of blood, which is useful in the determination of blood volume in children or in small animals in the laboratory. The measurement of blood volume of the mouse was done by using sup(99m)Tc method. The results were 1.70 +- 0.06 ml (6.35 +- 0.18%/gm), which coincided with the values reported previously. Because of it's short half life and low radiation dosage to the patients, sup(99m)Tc method will be recommended in the field of pediatrics or in patients with polycythemia or congestive heart failure, who are requested the repeated measurement of blood volume. (auth.)

  5. 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.

  6. Sup(99m) Technetium - labeled red blood cells 'in vitro'

    International Nuclear Information System (INIS)

    Bernardo Filho, M.; Souza Moura, I.N. de; Boasquevisque, E.M.

    1983-01-01

    A simple technique for the preparation of sup(99m) Tc labeled red blood cells using a comercial kit is described. To each 3ml of plain blood with anti-coagulant was added 1ml of solution of commercial kit with 6.8 μg of stannous chloride. This mixture was incubated in water bath, at 37 0 C, for 60 minutes. Then technetium-99m was added and the mixture was left for another ten minutes, in water bath, at 37 0 C. Under these conditions there was the best labeling of the red blood cells. Similar results were obtained with a solution of stannous chloride prepared freshly. The labeling is strong for 6.8 μg stannous chloride because the labeling was not removed by the several washes of the red blood cells or by the left in water bath. (Author) [pt

  7. Rotary orbital suspension culture of embryonic stem cell-derived neural stem/progenitor cells: impact of hydrodynamic culture on aggregate yield, morphology and cell phenotype.

    Science.gov (United States)

    Laundos, Tiago L; Silva, Joana; Assunção, Marisa; Quelhas, Pedro; Monteiro, Cátia; Oliveira, Carla; Oliveira, Maria J; Pêgo, Ana P; Amaral, Isabel F

    2017-08-01

    Embryonic stem (ES)-derived neural stem/progenitor cells (ES-NSPCs) constitute a promising cell source for application in cell therapies for the treatment of central nervous system disorders. In this study, a rotary orbital hydrodynamic culture system was applied to single-cell suspensions of ES-NSPCs, to obtain homogeneously-sized ES-NSPC cellular aggregates (neurospheres). Hydrodynamic culture allowed the formation of ES-NSPC neurospheres with a narrower size distribution than statically cultured neurospheres, increasing orbital speeds leading to smaller-sized neurospheres and higher neurosphere yield. Neurospheres formed under hydrodynamic conditions (72 h at 55 rpm) showed higher cell compaction and comparable percentages of viable, dead, apoptotic and proliferative cells. Further characterization of cellular aggregates provided new insights into the effect of hydrodynamic shear on ES-NSPC behaviour. Rotary neurospheres exhibited reduced protein levels of N-cadherin and β-catenin, and higher deposition of laminin (without impacting fibronectin deposition), matrix metalloproteinase-2 (MMP-2) activity and percentage of neuronal cells. In line with the increased MMP-2 activity levels found, hydrodynamically-cultured neurospheres showed higher outward migration on laminin. Moreover, when cultured in a 3D fibrin hydrogel, rotary neurospheres generated an increased percentage of neuronal cells. In conclusion, the application of a constant orbital speed to single-cell suspensions of ES-NSPCs, besides allowing the formation of homogeneously-sized neurospheres, promoted ES-NSPC differentiation and outward migration, possibly by influencing the expression of cell-cell adhesion molecules and the secretion of proteases/extracellular matrix proteins. These findings are important when establishing the culture conditions needed to obtain uniformly-sized ES-NSPC aggregates, either for use in regenerative therapies or in in vitro platforms for biomaterial development or

  8. Electrochemical properties of TiO{sub 2} encapsulated ZnO nanorod aggregates dye sensitized solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Justin Raj, C.; Karthick, S.N.; Dennyson Savariraj, A.; Hemalatha, K.V.; Park, Song-Ki; Kim, Hee-Je [Pusan National University, Department of Electrical Engineering, San 30, Jangjeong-Dong, Gumjeong-Ku, Busan 609 735 (Korea, Republic of); Prabakar, K., E-mail: prabakar@pusan.ac.kr [Pusan National University, Department of Electrical Engineering, San 30, Jangjeong-Dong, Gumjeong-Ku, Busan 609 735 (Korea, Republic of)

    2012-10-05

    Highlights: Black-Right-Pointing-Pointer ZnO nanorod aggregates were synthesized by simple co-precipitation technique. Black-Right-Pointing-Pointer TiO{sub 2} encapsulated ZnO nanorod aggregates photoanode was used for the DSSC. Black-Right-Pointing-Pointer TiO{sub 2} encapsulated ZnO nanorod aggregates shows an enhanced efficiency. Black-Right-Pointing-Pointer The electron recombination and transport properties were studied using EIS method. - Abstract: Dye sensitized solar cells based on TiO{sub 2} encapsulated ZnO nanorod (NR) aggregates were fabricated and electrochemical performance was analyzed using impedance spectroscopy as a function of forward bias voltage. Charge transfer properties such as electron life time ({tau}{sub n}), electron diffusion coefficient (D{sub n}) and electron diffusion length (L{sub n}) were calculated in order to ensure the influence of TiO{sub 2} layer over the ZnO NR aggregates. It is found that the short circuit current density (Jsc = 5.8 mA cm{sup -2}), open circuit potential (V{sub oc} = 0.743 V), fill factor (FF = 0.57) and conversion efficiency are significantly improved by the introduction of TiO{sub 2} layer over ZnO photoanode. A power conversion efficiency of about 2.48% has been achieved for TiO{sub 2}/ZnO cell, which is higher than that of bare ZnO NR aggregate based cells (1.73%). The formation of an inherent energy barrier between TiO{sub 2} and ZnO films and the passivation of surface traps on the ZnO film caused by the introduction of TiO{sub 2} layer increase the dye absorption and favor the electron transport which may be responsible for the enhanced performance of TiO{sub 2}/ZnO cell.

  9. Electrochemical properties of TiO2 encapsulated ZnO nanorod aggregates dye sensitized solar cells

    International Nuclear Information System (INIS)

    Justin Raj, C.; Karthick, S.N.; Dennyson Savariraj, A.; Hemalatha, K.V.; Park, Song-Ki; Kim, Hee-Je; Prabakar, K.

    2012-01-01

    Highlights: ► ZnO nanorod aggregates were synthesized by simple co-precipitation technique. ► TiO 2 encapsulated ZnO nanorod aggregates photoanode was used for the DSSC. ► TiO 2 encapsulated ZnO nanorod aggregates shows an enhanced efficiency. ► The electron recombination and transport properties were studied using EIS method. - Abstract: Dye sensitized solar cells based on TiO 2 encapsulated ZnO nanorod (NR) aggregates were fabricated and electrochemical performance was analyzed using impedance spectroscopy as a function of forward bias voltage. Charge transfer properties such as electron life time (τ n ), electron diffusion coefficient (D n ) and electron diffusion length (L n ) were calculated in order to ensure the influence of TiO 2 layer over the ZnO NR aggregates. It is found that the short circuit current density (Jsc = 5.8 mA cm −2 ), open circuit potential (V oc = 0.743 V), fill factor (FF = 0.57) and conversion efficiency are significantly improved by the introduction of TiO 2 layer over ZnO photoanode. A power conversion efficiency of about 2.48% has been achieved for TiO 2 /ZnO cell, which is higher than that of bare ZnO NR aggregate based cells (1.73%). The formation of an inherent energy barrier between TiO 2 and ZnO films and the passivation of surface traps on the ZnO film caused by the introduction of TiO 2 layer increase the dye absorption and favor the electron transport which may be responsible for the enhanced performance of TiO 2 /ZnO cell.

  10. Young endothelial cells revive aging blood.

    Science.gov (United States)

    Chang, Vivian Y; Termini, Christina M; Chute, John P

    2017-11-01

    The hematopoietic system declines with age, resulting in decreased hematopoietic stem cell (HSC) self-renewal capacity, myeloid skewing, and immune cell depletion. Aging of the hematopoietic system is associated with an increased incidence of myeloid malignancies and a decline in adaptive immunity. Therefore, strategies to rejuvenate the hematopoietic system have important clinical implications. In this issue of the JCI, Poulos and colleagues demonstrate that infusions of bone marrow (BM) endothelial cells (ECs) from young mice promoted HSC self-renewal and restored immune cell content in aged mice. Additionally, delivery of young BM ECs along with HSCs following total body irradiation improved HSC engraftment and enhanced survival. These results suggest an important role for BM endothelial cells (ECs) in regulating hematopoietic aging and support further research to identify the rejuvenating factors elaborated by BM ECs that restore HSC function and the immune repertoire in aged mice.

  11. 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...

  12. 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.

  13. 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...

  14. 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

  15. Consequences of dysregulated complement regulators on red blood cells

    NARCIS (Netherlands)

    Thielen, Astrid J. F.; Zeerleder, Sacha; Wouters, Diana

    2018-01-01

    The complement system represents the first line of defense that is involved in the clearance of pathogens, dying cells and immune complexes via opsonization, induction of an inflammatory response and the formation of a lytic pore. Red blood cells (RBCs) are very important for the delivery of oxygen

  16. 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 ...

  17. Leukemic Cells "Gas Up" Leaky Bone Marrow Blood Vessels.

    Science.gov (United States)

    Itkin, Tomer; Rafii, Shahin

    2017-09-11

    In this issue of Cancer Cell, Passaro et al. demonstrate how leukemia through aberrant induction of reactive oxygen species and nitric oxide production trigger marrow vessel leakiness, instigating pro-leukemic function. Disrupted tumor blood vessels promote exhaustion of non-malignant stem and progenitor cells and may facilitate leukemia relapse following chemotherapeutic treatment. Copyright © 2017. Published by Elsevier Inc.

  18. 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.

  19. Spinal cord homogenates from SOD1 familial amyotrophic lateral sclerosis induce SOD1 aggregation in living cells.

    Directory of Open Access Journals (Sweden)

    Edward Pokrishevsky

    Full Text Available Mutant Cu/Zn superoxide dismutase (SOD1 can confer its misfolding on wild-type SOD1 in living cells; the propagation of misfolding can also be transmitted between cells in vitro. Recent studies identified fluorescently-tagged SOD1G85R as a promiscuous substrate that is highly prone to aggregate by a variety of templates, in vitro and in vivo. Here, we utilized several SOD1-GFP reporter proteins with G37R, G85R, or G93A mutations in SOD1. We observed that human spinal cord homogenates prepared from SOD1 familial ALS (FALS can induce significantly more intracellular reporter protein aggregation than spinal cord homogenates from sporadic ALS, Alzheimer's disease, multiple system atrophy or healthy control individuals. We also determined that the induction of reporter protein aggregation by SOD1-FALS tissue homogenates can be attenuated by incubating the cells with the SOD1 misfolding-specific antibody 3H1, or the small molecule 5-fluorouridine. Our study further implicates SOD1 as the seeding particle responsible for the spread of SOD1-FALS neurodegeneration from its initial onset site(s, and demonstrates two potential therapeutic strategies for SOD1-mediated disease. This work also comprises a medium-throughput cell-based platform of screening potential therapeutics to attenuate propagated aggregation of SOD1.

  20. 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).

  1. Evaluation of two different protocols for peripheral blood stem cell collection with the Fresenius AS 104 blood cell separator.

    Science.gov (United States)

    Menichella, G; Lai, M; Pierelli, L; Vittori, M; Serafini, R; Ciarli, M; Foddai, M L; Salerno, G; Sica, S; Scambia, G; Leone, G; Bizzi, B

    1997-01-01

    Reconstitution of hematopoiesis by means of peripheral blood stem cells is a valid alternative to autologous bone marrow transplantation. The aim of this investigation was to increase the efficiency of collection of circulating blood progenitor cells and to obtain a purer product for transplant. We carried out leukapheresis procedures with the Fresenius AS 104 blood cell separator, using two different protocols, the previously used PBSC-LYM and a new mononuclear cell collection program. Both programs were highly effective in collecting mononuclear cells (MNC) and CD34+ cells. Some differences were found, especially regarding MNC yield and efficiencies. There are remarkable differences in the efficiency of collection of CD34+ cells (62.38% with the new program as opposed to 31.69% with the older one). Linear regression analysis showed a negative correlation between blood volume processed and MNC efficiency only for the PBSC-LYM program. Differences were also observed in the degree of inverse correlation existing in both programs between patients' white blood cell precount and MNC collection efficiency. The inverse correlation was stronger for the PBSC-LYM program. Seven patients with solid tumors and hematologic malignancies received high dose chemotherapy and were subsequently transplanted with peripheral blood stem cells collected using the new protocol. All patients obtained a complete and stable engraftment with the reinfusion product collected with one or two leukapheresis procedures. High efficiencies and yields were observed in the new protocol for MNC and CD34+ cells. These were able to effect rapid and complete bone marrow recovery after myeloablative chemotherapy.

  2. Hemostatic Status of Pre and Post Intracoronary Injection of Peripheral Blood Stem Cells in Patients with Recent Myocardial Infarction

    Directory of Open Access Journals (Sweden)

    Cosphiadi Irawan

    2014-01-01

    Full Text Available Aim: to investigate hemostatic parameter changes, such as platelet aggregation, blood and plasma viscosity, prothrombin time, APTT, CRP and fibrinogen, before and after administration of stem cell therapy. Methods: a total of 24 patients were enrolled. Peripheral blood stem cells (PBSCs were harvested and injected into the infarct-related artery after 5 consecutive days of G-CSF administration. Recombinant human erythropoietin was administered at the time of intracoronary PBSCs injection. Results: we were able to evaluate 11 from 24 of patients regarding hemostatic status pre–post stem cell injection. There were no significant difference between baseline vs 3 months in spontaneous aggregation (p=0.350, PT (p=0.793, aPTT (p=0.255 and TT (p=0.254. There were also no significant difference between baseline vs 3 months in plasma viscosity (p=0.442 and blood viscosity (p=0.843. Nevertheless the patient who had their blood and plasma viscosity above or below normal laboratory range return to normal level after the treatment. Both PT and APTT also show normalization value. Both Fibrinogen and CRP level show significant decrease between baseline and 3 months after treatment (p=0.009 and (p=0.04 respectively. Conclusion: combined G-CSF and EPO based-intracoronary infusion of PBSCs may open new perspective in the treatment of hypercoagulable state post AMI.

  3. Magnetic engineering of stable rod-shaped stem cell aggregates: circumventing the pitfall of self-bending.

    Science.gov (United States)

    Du, V; Fayol, D; Reffay, M; Luciani, N; Bacri, J-C; Gay, C; Wilhelm, C

    2015-02-01

    A current challenge for tissue engineering while restoring the function of diseased or damaged tissue is to customize the tissue according to the target area. Scaffold-free approaches usually yield spheroid shapes with the risk of necrosis at the center due to poor nutrient and oxygen diffusion. Here, we used magnetic forces developed at the cellular scale by miniaturized magnets to create rod-shaped aggregates of stem cells that subsequently matured into a tissue-like structure. However, during the maturation process, the tissue-rods spontaneously bent and coiled into sphere-like structures, triggered by the increasing cell-cell adhesion within the initially non-homogeneous tissue. Optimisation of the intra-tissular magnetic forces successfully hindered the transition, in order to produce stable rod-shaped stem cells aggregates.

  4. Platelet activation and aggregation

    DEFF Research Database (Denmark)

    Jensen, Maria Sander; Larsen, O H; Christiansen, Kirsten

    2013-01-01

    This study introduces a new laboratory model of whole blood platelet aggregation stimulated by endogenously generated thrombin, and explores this aspect in haemophilia A in which impaired thrombin generation is a major hallmark. The method was established to measure platelet aggregation initiated...

  5. 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 ...

  6. Optical and hydrodynamic stretching of single cells from blood

    DEFF Research Database (Denmark)

    Thirstrup, Henrik; Rungling, Tony B.; Khalil Al-Hamdani, Mustafa Zyad

    2017-01-01

    Mechanical properties, like deformability or elasticity, of cells can in some cases be indicative of the health of the organism they originate from. In this work, we explore the potential of deformability and other mechanical parameters of individual red blood cells (RBCs) from humans as a marker...... but does so far not allow for subsequent investigations of single "interesting" cells. The paper is a progress report with preliminary results based on the different strategies, we have pursued....

  7. A smart core-sheath nanofiber that captures and releases red blood cells from the blood

    Science.gov (United States)

    Shi, Q.; Hou, J.; Zhao, C.; Xin, Z.; Jin, J.; Li, C.; Wong, S.-C.; Yin, J.

    2016-01-01

    A smart core-sheath nanofiber for non-adherent cell capture and release is demonstrated. The nanofibers are fabricated by single-spinneret electrospinning of poly(N-isopropylacrylamide) (PNIPAAm), polycaprolactone (PCL) and nattokinase (NK) solution blends. The self-assembly of PNIPAAm and PCL blends during the electrospinning generates the core-sheath PCL/PNIPAAm nanofibers with PNIPAAm as the sheath. The PNIPAAm-based core-sheath nanofibers are switchable between hydrophobicity and hydrophilicity with temperature change and enhance stability in the blood. When the nanofibers come in contact with blood, the NK is released from the nanofibers to resist platelet adhesion on the nanofiber surface, facilitating the direct capture and isolation of red blood cells (RBCs) from the blood above phase-transition temperature of PNIPAAm. Meanwhile, the captured RBCs are readily released from the nanofibers with temperature stimuli in an undamaged manner. The release efficiency of up to 100% is obtained while maintaining cellular integrity and function. This work presents promising nanofibers to effectively capture non-adherent cells and release for subsequent molecular analysis and diagnosis of single cells.A smart core-sheath nanofiber for non-adherent cell capture and release is demonstrated. The nanofibers are fabricated by single-spinneret electrospinning of poly(N-isopropylacrylamide) (PNIPAAm), polycaprolactone (PCL) and nattokinase (NK) solution blends. The self-assembly of PNIPAAm and PCL blends during the electrospinning generates the core-sheath PCL/PNIPAAm nanofibers with PNIPAAm as the sheath. The PNIPAAm-based core-sheath nanofibers are switchable between hydrophobicity and hydrophilicity with temperature change and enhance stability in the blood. When the nanofibers come in contact with blood, the NK is released from the nanofibers to resist platelet adhesion on the nanofiber surface, facilitating the direct capture and isolation of red blood cells (RBCs) from

  8. The effect of the colostral cells on gene expression of cytokines in cord blood cells.

    Science.gov (United States)

    Hrdý, Jiří; Novotná, Olga; Kocourková, Ingrid; Prokešová, Ludmila

    2017-11-01

    Beneficial effect of maternal milk is acknowledged, but there is still question whether maternal milk from allergic mother is as good as from healthy one. In our study, we have assayed the effect of cells from colostrum of healthy and allergic mothers on gene expression of cytokines in cord blood cells of newborns of healthy and allergic mothers. Cytokines typical for Th1 (IL-2, IFN-gamma), Th2 (IL-4, IL-13), Tregs (IL-10, TGF-beta), and IL-8 were followed. We were not able to detect significant influence of colostral cells on gene expression of cytokines in cord blood after 2-day coculture using Transwell system. There was no difference in gene expression of cytokines in nonstimulated cord blood cells of newborns of healthy and allergic mothers, but generally increased gene expression of cytokines except IL-10 and TGF-beta after polyclonal stimulation was detected in cord blood cells of children of allergic mothers. There was no difference in IL-10 expression in stimulated cord blood cells of children of healthy and allergic mothers. Gene expression of TGF-beta was even decreased in stimulated cord blood cells of children of allergic mothers in comparison to healthy ones. We have not observed difference in the capacity of colostral cells of healthy and allergic mothers to influence gene expression of cytokines in cord blood cells, but we have described difference in the reactivity of cord blood cells between children of allergic and healthy mothers.

  9. Blood

    Science.gov (United States)

    ... a reduced 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 ...

  10. Cluster–cluster aggregation with particle replication and chemotaxy: a simple model for the growth of animal cells in culture

    International Nuclear Information System (INIS)

    Alves, S G; Martins, M L

    2010-01-01

    Aggregation of animal cells in culture comprises a series of motility, collision and adhesion processes of basic relevance for tissue engineering, bioseparations, oncology research and in vitro drug testing. In the present paper, a cluster–cluster aggregation model with stochastic particle replication and chemotactically driven motility is investigated as a model for the growth of animal cells in culture. The focus is on the scaling laws governing the aggregation kinetics. Our simulations reveal that in the absence of chemotaxy the mean cluster size and the total number of clusters scale in time as stretched exponentials dependent on the particle replication rate. Also, the dynamical cluster size distribution functions are represented by a scaling relation in which the scaling function involves a stretched exponential of the time. The introduction of chemoattraction among the particles leads to distribution functions decaying as power laws with exponents that decrease in time. The fractal dimensions and size distributions of the simulated clusters are qualitatively discussed in terms of those determined experimentally for several normal and tumoral cell lines growing in culture. It is shown that particle replication and chemotaxy account for the simplest cluster size distributions of cellular aggregates observed in culture

  11. 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.

  12. In vitro aggregation behavior of a non-amyloidogenic λ light chain dimer deriving from U266 multiple myeloma cells.

    Directory of Open Access Journals (Sweden)

    Paolo Arosio

    Full Text Available Excessive production of monoclonal light chains due to multiple myeloma can induce aggregation-related disorders, such as light chain amyloidosis (AL and light chain deposition diseases (LCDD. In this work, we produce a non-amyloidogenic IgE λ light chain dimer from human mammalian cells U266, which originated from a patient suffering from multiple myeloma, and we investigate the effect of several physicochemical parameters on the in vitro stability of this protein. The dimer is stable in physiological conditions and aggregation is observed only when strong denaturating conditions are applied (acidic pH with salt at large concentration or heating at melting temperature T(m at pH 7.4. The produced aggregates are spherical, amorphous oligomers. Despite the larger β-sheet content of such oligomers with respect to the native state, they do not bind Congo Red or ThT. The impossibility to obtain fibrils from the light chain dimer suggests that the occurrence of amyloidosis in patients requires the presence of the light chain fragment in the monomer form, while dimer can form only amorphous oligomers or amorphous deposits. No aggregation is observed after denaturant addition at pH 7.4 or at pH 2.0 with low salt concentration, indicating that not a generic unfolding but specific conformational changes are necessary to trigger aggregation. A specific anion effect in increasing the aggregation rate at pH 2.0 is observed according to the following order: SO(4(-≫Cl(->H(2PO(4(-, confirming the peculiar role of sulfate in promoting protein aggregation. It is found that, at least for the investigated case, the mechanism of the sulfate effect is related to protein secondary structure changes induced by anion binding.

  13. 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

  14. The Effect of Calcination Temperature on the Performance of TiO2 Aggregates-based Dye Solar Cells (DSCs)

    International Nuclear Information System (INIS)

    Siti Nur Azella Zaine; Norani Muti Mohamed; Mohamad Azmi Bustam

    2011-01-01

    In this paper, the effect of calcination temperature on the physicochemical properties of synthesized TiO 2 aggregates and their influence on overall light conversion efficiency of dye solar cell (DSc) were investigated. Samples of TiO 2 aggregates (mean size of 0.45 μm) composing of nano crystallites (10-40 nm) were synthesized through hydrolysis of dilute titanium alkoxide in ethanol. Phase and microstructure of the TiO 2 obtained have been characterized using FESEM, XRD and UV-Vis spectroscopy. I-V characterization shows that TiO 2 aggregates based DSC demonstrated better performance compared to nanoparticles (P-25)-based DSC. The optimum calcination temperature was found to be about 500 degree Celsius with efficiency of 4.456 %, which is 30 % increment compared to P-25-based DSC under the same condition. (author)

  15. Aggregation of gold nanoparticles followed by methotrexate release enables Raman imaging of drug delivery into cancer cells

    International Nuclear Information System (INIS)

    Durgadas, C. V.; Sharma, C. P.; Paul, W.; Rekha, M. R.; Sreenivasan, K.

    2012-01-01

    This study refers an aqueous synthesis of methotrexate (MTX)-conjugated gold nanoparticles (GNPs), their interaction with HepG2 cells, and the use of Raman imaging to observe cellular internalization and drug delivery. GNPs of average size 3.5–5 nm were stabilized using the amine terminated bifunctional biocompatible copolymer and amended by conjugating MTX, an anticancer drug. The nanoparticles were released MTX at a faster rate in acidic pH and subsequently found to form aggregates. The Raman signals of cellular components were found to be enhanced by the aggregated particles enabling the mapping to visualize site-specific drug delivery. The methodology seems to have potential in optimizing the characteristics of nanodrug carriers for emptying the cargo precisely at specified sites.Graphical AbstractDrug release induced particle aggregation enhances Raman signals to aid in imaging.

  16. 3D printing human induced pluripotent stem cells with novel hydroxypropyl chitin bioink: scalable expansion and uniform aggregation.

    Science.gov (United States)

    Li, Yang; Jiang, Xulin; Li, Ling; Chen, Zhi-Nan; Gao, Ge; Yao, Rui; Sun, Wei

    2018-06-28

    Human induced pluripotent stem cells (hiPSCs) are more likely to successfully avoid the immunological rejection and ethical problems that are often encountered by human embryonic stem cells in various stem cell studies and applications. To transfer hiPSCs from the laboratory to clinical applications, researchers must obtain sufficient cell numbers. In this study, 3D cell printing was used as a novel method for iPSC scalable expansion. Hydroxypropyl chitin (HPCH), utilized as a new type of bioink, and a set of optimized printing parameters were shown to achieve high cell survival (> 90%) after the printing process and high proliferation efficiency (~ 32.3 folds) during subsequent 10-day culture. After the culture, high levels of pluripotency maintenance were recognized by both qualitative and quantitative detections. Compared with static suspension (SS) culture, hiPSC aggregates formed in 3D printed constructs showed a higher uniformity in size. Using novel dual-fluorescent labelling method, hiPSC aggregates in the constructs were found more inclined to form by in situ proliferation rather than multicellular aggregation. This study revealed unique advantages of non-ionic crosslinking bioink material HPCH, including high gel strength and rapid temperature response in hiPSC printing, and achieved primed state hiPSC printing for the first time. Features achieved in this study, such as high cell yield, high pluripotency maintenance and uniform aggregation provide good foundations for further hiPSC studies on 3D micro-tissue differentiation and drug screening. © 2018 IOP Publishing Ltd.

  17. Intracellular response to process optimization and impact on productivity and product aggregates for a high-titer CHO cell process.

    Science.gov (United States)

    Handlogten, Michael W; Lee-O'Brien, Allison; Roy, Gargi; Levitskaya, Sophia V; Venkat, Raghavan; Singh, Shailendra; Ahuja, Sanjeev

    2018-01-01

    A key goal in process development for antibodies is to increase productivity while maintaining or improving product quality. During process development of an antibody, titers were increased from 4 to 10 g/L while simultaneously decreasing aggregates. Process development involved optimization of media and feed formulations, feed strategy, and process parameters including pH and temperature. To better understand how CHO cells respond to process changes, the changes were implemented in a stepwise manner. The first change was an optimization of the feed formulation, the second was an optimization of the medium, and the third was an optimization of process parameters. Multiple process outputs were evaluated including cell growth, osmolality, lactate production, ammonium concentration, antibody production, and aggregate levels. Additionally, detailed assessment of oxygen uptake, nutrient and amino acid consumption, extracellular and intracellular redox environment, oxidative stress, activation of the unfolded protein response (UPR) pathway, protein disulfide isomerase (PDI) expression, and heavy and light chain mRNA expression provided an in-depth understanding of the cellular response to process changes. The results demonstrate that mRNA expression and UPR activation were unaffected by process changes, and that increased PDI expression and optimized nutrient supplementation are required for higher productivity processes. Furthermore, our findings demonstrate the role of extra- and intracellular redox environment on productivity and antibody aggregation. Processes using the optimized medium, with increased concentrations of redox modifying agents, had the highest overall specific productivity, reduced aggregate levels, and helped cells better withstand the high levels of oxidative stress associated with increased productivity. Specific productivities of different processes positively correlated to average intracellular values of total glutathione. Additionally

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

    Science.gov (United States)

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

    2015-01-01

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

  19. 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.

  20. Comparison of Modified Impedance Whole Blood Platelet Aggregation Method Detecting Platelet Function in ACS Patients with Different CYP2C19 Genotypes.

    Science.gov (United States)

    Cui, Chanjuan; Qiao, Rui; Zhang, Jie

    2016-01-01

    A reliable laboratory test to monitor onclopidogrel platelet reactivity (PR) is very necessary. In addition, genetic factors also play an important part in onclopidogrel PR. This study aimed to modify the original impedance whole blood platelet aggregation assay associated with the release assay to monitor onclopidogrel PR and assess their relationship with genotype. We adjusted the concentration of calcium in the in vitro reaction system of platelet aggregation to modify the original impedance whole blood platelet aggregation assay. Meanwhile, chronolume, which quantified the adenosine triphosphate (ATP) released from platelet dense granules, is added to this reaction system to reflect the platelet release function. In the modified assay, platelet magnified activation time (MAT) and the maximal platelet ATP release value (RV) were used to reflect platelet function parameters. In the original assay, the electrical resistance (omega) and RV were used to reflect platelet function parameters. Onclopidogrel PR was detected by the original impedance whole blood platelet aggregation assay, modified assay, and flow cytometric vasodilator stimulated phosphoprotein (VASP) assay in 168 patients with acute coronary syndromes (ACS). CYP2C19*2 and CYP2C19*3 polymorphisms were also detected in all of these patients. This modified method showed that when 12.5 microL CaCl2 (0.2 mmol/L) was added to the reaction system, MAT was appropriate (93 +/- 23 seconds). The CVs for the modified impedance assay and release assay were 9.31% and 6.13%, respectively. The mean VASP-PRI in the patient group treated with clopidogrel was significantly lower than that in the control group without antiplatelet therapy (54.88 +/- 16.81% vs. 79.86 +/- 10.24%, p 50% group were shorter than that in the PRI 50% group were higher than that in the PRI omega) and RV of the original method showed no differences between the two groups [0 (0-2) vs. 0 (0-1.25), 0.05 (0-0.25) vs. 0.08 (0-0.24); p > 0.05, p > 0

  1. CD163 positive subsets of blood dendritic cells

    DEFF Research Database (Denmark)

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

    2006-01-01

    CD163 and CD91 are scavenging receptors with highly increased expression during the differentiation of monocytes into the anti-inflammatory macrophage phenotype. In addition, CD91 is expressed in monocyte-derived dendritic cells (MoDCs), where the receptor is suggested to be important...... for internalization of CD91-targeted antigens to be presented on the dendritic cell surface for T-cell stimulation. Despite their overlap in functionality, the expression of CD91 and CD163 has never been compared and the expression of CD163 in the monocyte-dendritic cell lineage is not yet characterized. CD163...... 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...

  2. 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

  3. Plasminogen-induced aggregation of PANC-1 cells requires conversion to plasmin and is inhibited by endogenous plasminogen activator inhibitor-1.

    Science.gov (United States)

    Deshet, Naamit; Lupu-Meiri, Monica; Espinoza, Ingrid; Fili, Oded; Shapira, Yuval; Lupu, Ruth; Gershengorn, Marvin C; Oron, Yoram

    2008-09-01

    PANC-1 cells express proteinase-activated receptors (PARs)-1, -2, and respond to their activation by transient elevation of cytosolic [Ca(2+)] and accelerated aggregation (Wei et al., 2006, J Cell Physiol 206:322-328). We studied the effect of plasminogen (PGN), an inactive precursor of the PAR-1-activating protease, plasmin (PN) on aggregation of pancreatic adenocarcinoma (PDAC) cells. A single dose of PGN time- and dose-dependently promoted PANC-1 cells aggregation in serum-free medium, while PN did not. PANC-1 cells express urokinase plasminogen activator (uPA), which continuously converted PGN to PN. This activity and PGN-induced aggregation were inhibited by the uPA inhibitor amiloride. PGN-induced aggregation was also inhibited by alpha-antiplasmin and by the PN inhibitor epsilon-aminocaproic acid (EACA). Direct assay of uPA activity revealed very low rate, markedly enhanced in the presence of PGN. Moreover, in PGN activator inhibitor 1-deficient PANC-1 cells, uPA activity and PGN-induced aggregation were markedly potentiated. Two additional human PDAC cell lines, MiaPaCa and Colo347, were assayed for PGN-induced aggregation. Both cell lines responded by aggregation and exhibited PGN-enhanced uPA activity. We hypothesized that the continuous conversion of PGN to PN by endogenous uPA is limited by PN's degradation and negatively controlled by endogenously produced PAI-1. Indeed, we found that PANC-1 cells inactivate PN with t1/2 of approximately 7 h, while the continuous addition of PN promoted aggregation. Our data suggest that PANC-1 cells possess intrinsic, PAI-1-sensitive mechanism for promotion of aggregation and differentiation by prolonged exposure to PGN and, possibly, additional precursors of PARs agonists.

  4. Neuropilin-1 Is Expressed on Lymphoid Tissue Residing LTi-like Group 3 Innate Lymphoid Cells and Associated with Ectopic Lymphoid Aggregates.

    Science.gov (United States)

    Shikhagaie, Medya Mara; Björklund, Åsa K; Mjösberg, Jenny; Erjefält, Jonas S; Cornelissen, Anne S; Ros, Xavier Romero; Bal, Suzanne M; Koning, Jasper J; Mebius, Reina E; Mori, Michiko; Bruchard, Melanie; Blom, Bianca; Spits, Hergen

    2017-02-14

    Here, we characterize a subset of ILC3s that express Neuropilin1 (NRP1) and are present in lymphoid tissues, but not in the peripheral blood or skin. NRP1 + group 3 innate lymphoid cells (ILC3s) display in vitro lymphoid tissue inducer (LTi) activity. In agreement with this, NRP1 + ILC3s are mainly located in proximity to high endothelial venules (HEVs) and express cell surface molecules involved in lymphocyte migration in secondary lymphoid tissues via HEVs. NRP1 was also expressed on mouse fetal LTi cells, indicating that NRP1 is a conserved marker for LTi cells. Human NRP1 + ILC3s are primed cells because they express CD45RO and produce higher amounts of cytokines than NRP1 - cells, which express CD45RA. The NRP1 ligand vascular endothelial growth factor A (VEGF-A) served as a chemotactic factor for NRP1 + ILC3s. NRP1 + ILC3s are present in lung tissues from smokers and patients with chronic obstructive pulmonary disease, suggesting a role in angiogenesis and/or the initiation of ectopic pulmonary lymphoid aggregates. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

  5. 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...

  6. Histomorphometric study on blood cells in male adult ostrich

    Directory of Open Access Journals (Sweden)

    Mina Tadjalli

    2013-09-01

    Full Text Available In order to perform a histomorphometric study of blood cells in male adult ostrich, blood samples were obtained from jugular vein of 10 clinically healthy male adult ostriches (2 - 3 years old. The slides were stained with the Giemsa methods and the smears were evaluated for cellular morphology, with cellular size being determined by micrometry. The findings of this study revealed that the shape of the cell, cytoplasm and nucleus of erythrocytes in male adult ostriches were similar to those in other birds such as quails, chickens, Iranian green-head ducks.

  7. Labelling of red blood cells with 99m pertechnetate

    International Nuclear Information System (INIS)

    Vyth, A.; Raam, C.F.

    1979-07-01

    This paper describes a method for labelling red blood cells with 99mTc in vitro, using electrolytically generated stannous ions as the reducing agent for 99mTc-pertechnetate. A labelling of 95% was found. A method for the in vivo labelling of red blood cells is also reported. This involves an injection of a stanno-DTPA-complex followed 20 minutes later by a 99mTc-pertechnetate solution scintillation camera images show more background activity when the in vivo method of labelling is used

  8. Blood cell labeling with technetium-99m. II. Measurement of circulating blood volume by sup(99m)Tc-labeled red blood cells

    Energy Technology Data Exchange (ETDEWEB)

    Uchida, T; Yoshida, H; Matsuda, S; Kimura, H; Miura, N [Fukushima Medical Coll. (Japan)

    1978-02-01

    Using a labeling method with sup(99m)Tc-pertechnetate to red blood cells (RBC), circulating blood volume was measured in comparison with that from /sup 51/Cr-labeled RBC method. The technique is easier than already published methods, because CIS kit for sup(99m)Tc-RBC labeling (TCK-11) became to be available recently. Two mls of ACD-anticoagulated blood were withdrawn and 0.5 ml of reducing reagent prepared just before use was added to blood, waiting 5 minutes and discarding the serum after centrifugation, then adding 100 ..mu..Ci of sup(99m)Tc. After washing the labeled cells by isotonic saline, cells were re-suspended in 10 ml of saline and injected to the subject. Blood specimen was obtained 10, 30, 60 and 120 minutes after infusion and blood volume was calculated by the usual way. Circulating blood volume by sup(99m)Tc was well correlated with that by /sup 51/Cr (=0.98, p 0.01), however, the value calculated from sup(99m)Tc were 4.8 percent higher than those by /sup 51/Cr, which suggested the elution of sup(99m)Tc from labeled RBC. sup(99m)Tc method has the advantages that higher radioactivity can be obtained in small amount of blood, which is useful in the determination of blood volume in children or in small animals in the laboratory. The measurement of blood volume of the mouse was done by using sup(99m)Tc method. The results were 1.70 +- 0.06 ml (6.35 +- 0.18%/gm), which coincided with the values reported previously. Because of it's short half life and low radiation dosage to the patients, sup(99m)Tc method will be recommended in the field of pediatrics or in patients with polycythemia or congestive heart failure, who are requested the repeated measurement of blood volume.

  9. 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.

  10. 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

  11. A particle-based model to simulate the micromechanics of single-plant parenchyma cells and aggregates

    International Nuclear Information System (INIS)

    Van Liedekerke, P; Tijskens, E; Smeedts, B; Ramon, H; Ghysels, P; Samaey, G; Roose, D

    2010-01-01

    This paper is concerned with addressing how plant tissue mechanics is related to the micromechanics of cells. To this end, we propose a mesh-free particle method to simulate the mechanics of both individual plant cells (parenchyma) and cell aggregates in response to external stresses. The model considers two important features in the plant cell: (1) the cell protoplasm, the interior liquid phase inducing hydrodynamic phenomena, and (2) the cell wall material, a viscoelastic solid material that contains the protoplasm. In this particle framework, the cell fluid is modeled by smoothed particle hydrodynamics (SPH), a mesh-free method typically used to address problems with gas and fluid dynamics. In the solid phase (cell wall) on the other hand, the particles are connected by pairwise interactions holding them together and preventing the fluid to penetrate the cell wall. The cell wall hydraulic conductivity (permeability) is built in as well through the SPH formulation. Although this model is also meant to be able to deal with dynamic and even violent situations (leading to cell wall rupture or cell–cell debonding), we have concentrated on quasi-static conditions. The results of single-cell compression simulations show that the conclusions found by analytical models and experiments can be reproduced at least qualitatively. Relaxation tests revealed that plant cells have short relaxation times (1 µs–10 µs) compared to mammalian cells. Simulations performed on cell aggregates indicated an influence of the cellular organization to the tissue response, as was also observed in experiments done on tissues with a similar structure

  12. Indium-111 oxine labelling of white blood cells

    International Nuclear Information System (INIS)

    Lavender, J.P.; Silvester, D.J.; Goldman, J.; Hammersmith Hospital, London

    1978-01-01

    Following work done by Professor John McAfee and Mathew Thakur at the MRS Cyclotron Unit a method is available for labelling cells with indium-111 which results in a stable intracellular marker. The method uses indium-111-8 hydroxyquinoline (111In oxine) which is a lipoid soluble complex which goes across the cell membrane and results in the deposition of indium into various subcellular structures. It has been applied to various preparations of white cells, platelets and also malignant cells. Autologous granulocytes have been used to identify inflammatory lesions in 35 patients. By similar means autologous lymphocytes can also be labelled and reinfused. Lymphocytes have been shown in animals to circulate from the blood via the lymphatic system and then returning to the blood once more. The same phenomenon can be seen in man using indium labelled lymphocytes. Lymph nodes become visible at between 12 and 18 hours and recirculation of labelled cells can be shown on the blood activity curves. Certain problems arise concerning cell behaviour after labelling which appear due to irradiation of cells rather than chemical toxicity. (author)

  13. The influence of nanodiamond on the oxygenation states and micro rheological properties of human red blood cells in vitro.

    Science.gov (United States)

    Lin, Yu-Chung; Tsai, Lin-Wei; Perevedentseva, Elena; Chang, Hsin-Hou; Lin, Ching-Hui; Sun, Der-Shan; Lugovtsov, Andrei E; Priezzhev, Alexander; Mona, Jani; Cheng, Chia-Liang

    2012-10-01

    Nanodiamond has been proven to be biocompatible and proposed for various biomedical applications. Recently, nanometer-sized diamonds have been demonstrated as an effective Raman/fluorescence probe for bio-labeling, as well as, for drug delivery. Bio-labeling/drug delivery can be extended to the human blood system, provided one understands the interaction between nanodiamonds and the blood system. Here, the interaction of nanodiamonds (5 and 100 nm) with human red blood cells (RBC) in vitro is discussed. Measurements have been facilitated using Raman spectroscopy, laser scanning fluorescence spectroscopy, and laser diffractometry (ektacytometry). Data on cell viability and hemolytic analysis are also presented. Results indicate that the nanodiamonds in the studied condition do not cause hemolysis, and the cell viability is not affected. Importantly, the oxygenation/deoxygenation process was not found to be altered when nanodiamonds interacted with the RBC. However, the nanodiamond can affect some RBC properties such as deformability and aggregation in a concentration dependent manner. These results suggest that the nanodiamond can be used as an effective bio-labeling and drug delivery tool in ambient conditions, without complicating the blood's physiological conditions. However, controlling the blood properties including deformability of RBCs and rheological properties of blood is necessary during treatment.

  14. 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.

  15. 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

  16. 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.

  17. 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.

  18. Rates of Blood Formation and of Blood-Cell Depletion and Recovery after Irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Patt, H. M. [University of California, San Francisco, CA (United States)

    1967-07-15

    During the past decade or so, the study of radiation effects on cell renewal systems has moved more and more from the realm of description to that of analysis. There are several reasons for this development and paramount among these has been the introduction of techniques for study of the life history of organized cell populations, and the radiation survival kinetics of their components . In this paper I wish first to examine some basic parameters of normal haematopoiesis that are pertinent to understanding' radiation effects, and then to consider the radiosensitivity of blood cells as individual entities and as components of organized systems.

  19. 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)

  20. 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.

  1. Kinetics of red blood cell rouleaux formation studied by light scattering.

    Science.gov (United States)

    Szolna-Chodór, Alicja; Bosek, Maciej; Grzegorzewski, Bronislaw

    2015-02-01

    Red blood cell (RBC) rouleaux formation was experimentally studied using a light scattering technique. The suspensions of RBCs were obtained from the blood of healthy donors. Hematocrit of the samples was adjusted ranging from 1% to 4%. Measurements of the intensity of the coherent component of light scattered by the suspensions were performed and the scattering coefficient of the suspensions was determined. The number of RBCs per rouleaux was obtained using anomalous diffraction theory. The technique was used to show the effect of time, hematocrit, and sample thickness on the process. The number of cells per rouleaux first increases linearly, reaches a critical value at ∼3 cells per rouleaux, and then a further increase in the rouleaux size is observed. The kinetic constant of the rouleaux growth in the linear region is found to be independent of hematocrit. The aggregation rate increases as the sample thickness increases. The time at which the critical region appears strongly decreases as the hematocrit of the suspension increases. © 2015 Society of Photo-Optical Instrumentation Engineers (SPIE)

  2. 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

  3. 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 ...

  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. Cord Blood Stem Cell Procurement in Minority Donors

    National Research Council Canada - National Science Library

    Ratanatharathorn, Voravit

    2008-01-01

    ... of building minority CBU inventory. This final annual report is to give the report of the transplantation outcomes of African/American CBU recipients compared with other racial groups. This analysis is limited to those patients who have received an allogeneic cord blood stem cell transplantation at Karmanos Cancer Center.

  6. 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.

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

    DEFF Research Database (Denmark)

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

    2009-01-01

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

  8. 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....

  9. 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 (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Manual Hematology Devices § 864.6160 Manual...

  10. 21 CFR 864.5240 - Automated blood cell diluting apparatus.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Automated blood cell diluting apparatus. 864.5240 Section 864.5240 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Automated and Semi-Automated Hematology Devices...

  11. 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

  12. 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 ...

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

    NARCIS (Netherlands)

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

    2014-01-01

    Macrophages tightly control the production and clearance of red blood cells (RBC). During steady state hematopoiesis, approximately 10(10) RBC are produced per hour within erythroblastic islands in humans. In these erythroblastic islands, resident bone marrow macrophages provide erythroblasts with

  14. 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)

  15. 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.

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

    Science.gov (United States)

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

    2016-11-01

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

  17. 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.

  18. Red blood cell-deformability measurement: review of techniques.

    Science.gov (United States)

    Musielak, M

    2009-01-01

    Cell-deformability characterization involves general measurement of highly complex relationships between cell biology and physical forces to which the cell is subjected. The review takes account of the modern technical solutions simulating the action of the force applied to the red blood cell in macro- and microcirculation. Diffraction ektacytometers and rheoscopes measure the mean deformability value for the total red blood cell population investigated and the deformation distribution index of individual cells, respectively. Deformation assays of a whole single cell are possible by means of optical tweezers. The single cell-measuring setups for micropipette aspiration and atomic force microscopy allow conducting a selective investigation of deformation parameters (e.g., cytoplasm viscosity, viscoelastic membrane properties). The distinction between instrument sensitivity to various RBC-rheological features as well as the influence of temperature on measurement are discussed. The reports quoted confront fascinating possibilities of the techniques with their medical applications since the RBC-deformability has the key position in the etiology of a wide range of conditions.

  19. Hematology, cytochemistry and ultrastructure of blood cells in fishing cat (Felis viverrina).

    Science.gov (United States)

    Prihirunkit, Kreangsak; Salakij, Chaleow; Apibal, Suntaree; Narkkong, Nual Anong

    2007-06-01

    Hematological, cytochemical and ultrastructural features of blood cells in fishing cat (Felis viverrina) were evaluated using complete blood cell counts with routine and cytochemical blood stains, and scanning and transmission electron microscopy. No statistically significant difference was found in different genders of this animal. Unique features of blood cells in this animal were identified in hematological, cytochemical and ultrastructural studies. This study contributes to broaden hematological resources in wildlife animals and provides a guideline for identification of blood cells in the fishing cat.

  20. 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.

  1. Umbilical Cord Blood Stem Cells. Who has the right word?

    Directory of Open Access Journals (Sweden)

    Gisela Laporta

    2014-12-01

    Full Text Available In this article we analyze bioethical and legal aspects related to the cryopreservation of cord blood stem cells in Argentina. To unify definitions, the concept and variety of stem cells, together with the understanding of the means to obtain and store umbilical cord blood stem cells, are provided.  Options that arise in our country, mainly analyzing the conceptual differences underlying legal body and parts by public and private biobanks, are described. Additionally, the current Argentinean legislation and circumstances arising from a resolution which INCUCAI sought to regulate private biobanks, is analyzed. This analysis leads to thoughts on the way conflicts are solved when the health and life of people are judicialized. In this particular case, the appearance of a complex new topic which gives rise to new social and healthcare scenarios, must be further understood.

  2. ASSOCIATION OF BIRTH ASPHYXIA WITH CORD BLOOD NUCLEATED RED BLOOD CELL

    Directory of Open Access Journals (Sweden)

    Poornima Shankar

    2018-02-01

    Full Text Available BACKGROUND Asphyxia can lead to severe hypoxic ischaemic organ damage in new-borns which may cause postnatal manifestation of hypoxicischaemic encephalopathy. Studies have found that the Apgar score failed to predict specific neurologic outcomes of the infants. Increased cord blood nucleated red blood cell in term neonates is an indicator of chronic intrauterine hypoxia. We set out to assess the role of nucleated RBC as a non-invasive, easy, cheap and at the same time early biochemical means of asphyxia diagnosis in our clinical setting. MATERIALS AND METHODS All inborn babies with Apgar scores <7 at 1 and 5 minutes of life were reviewed. Relevant information from mother case sheet were obtained. Cord blood samples was drawn and sent for blood gas analysis and number of NRBCs/100 white blood cells (WBC was determined using Leishman stain. RESULTS Our study proves the relevance of increase nucleated RBC in terms of early detection of birth asphyxia. Most common cause of birth asphyxia found was meconium aspiration. No co-relation was found with chorioamnionitis or maternal obstetrical history. CONCLUSION Many specific biomarkers are being investigated now a day for early detection of birth asphyxia. Umbilical cord pH is costly and may be underestimated in birth asphyxia. In our study, the elevated cord blood nRBC count was shown to be a good predictor of perinatal asphyxia. Since, it is cost-effective and does not require any special expertise or any high-tech facilities, it may be a useful, reliable, inexpensive and easily available marker to evaluate perinatal asphyxia. Hence, increase nucleated RBC has an important role in diagnosing and predicting the outcome of perinatal asphyxia.

  3. 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

  4. 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

  5. A comparative study of BioAggregate and ProRoot MTA on adhesion, migration, and attachment of human dental pulp cells.

    Science.gov (United States)

    Zhu, Lingxin; Yang, Jingwen; Zhang, Jie; Peng, Bin

    2014-08-01

    The aim of the present study was to evaluate the effects of a novel bioceramic nanoparticular cement, BioAggregate (Innovative Bioceramix, Vancouver, BC, Canada), on the adhesion, migration, and attachment of human dental pulp cells (HDPCs) and to compare its performance with that of ProRoot mineral trioxide aggregate (MTA) (Dentsply, Tulsa, OK). Primary cultured HDPCs were treated with various dilutions of BioAggregate and MTA extracts to assess the cell viability using the Cell Counting Kit-8 (Dojindo, Kumamoto, Japan). Cell adhesion assay was performed using type I collagen-coated plates. An in vitro scratch wound healing model was used to determine cell migration. Focal adhesion formation and cytoskeleton organization were further examined by double immunofluorescence labeling for vinculin and fibrous actin. To assess cell attachment, HDPCs were directly seeded onto the material surfaces and observed by scanning electron microscopy. HDPCs exposed to BioAggregate extracts showed the highest viabilities at all extract concentrations at 24 and 48 hours, whereas cells exposed to original MTA extracts displayed suppressed viabilities at 72 hours compared with the control. Treatment with BioAggregate extracts enhanced cellular adhesion and migration of HDPCs in a concentration-dependent manner, which was superior to the effects induced by MTA extracts. Immunofluorescence staining indicated that both BioAggregate and MTA optimized focal adhesion formation and stress fiber assembly. Furthermore, scanning electron microscopic analysis revealed that HDPCs attached onto BioAggregate were more flattened and exhibited better spreading than cells on MTA. BioAggregate is able to promote cellular adhesion, migration, and attachment of HDPCs, indicating its excellent cytocompatibility. Therefore, BioAggregate appears to be a possible alternative to MTA for pulp capping. Copyright © 2014 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  6. 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)

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1986-05-01

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

  8. Studies on sequestration of neuraminidase-treated red blood cells

    International Nuclear Information System (INIS)

    Simchon, S.; Jan, K.M.; Chien, S.

    1988-01-01

    The effects of reduction in the surface charge of red blood cells (RBCs) on regional blood flow and RBC distribution were studied in rats anesthetized with pentobarbital sodium. RBCs were treated with neuraminidase to reduce their electrophoretic mobility by 56%. Normal and neuraminidase-treated RBCs labeled with 51Cr or 111In were injected into a femoral vein while an equal volume of blood was simultaneously withdrawn from a femoral artery. More than 70% of the neuraminidase-treated RBCs injected disappeared from the circulating blood in 30 min compared with less than 2% of normal RBCs. The relative distributions of neuraminidase-treated RBCs to normal RBCs, as determined from radioactivity counting, were significantly greater than 1 in the spleen (5.65 +/- 0.97, mean +/- SD), the liver (2.84 +/- 0.21), the lung (1.48 +/- 0.31), and the kidney (1.49 +/- 0.27), indicating a preferential trapping of neuraminidase-treated RBCs in these regions. This ratio was approximately 1 in all other organs. Regional blood flows in tissues were determined with 15-micron microspheres in the control period and after the infusion of neuraminidase-treated RBCs (experimental). Experimental-to-control blood flow ratios were 0.40 +/- 0.05 in the spleen, 0.66 +/- 0.06 in the liver, 0.78 +/- 0.03 in the lung, and 0.78 +/- 0.09 in the kidneys; this ratio was approximately 1 in all other organs. An experimental-to-control blood flow ratio less than 1 indicates a reduction in blood flow; this occurred in the same organs as those with trapping of neuraminidase-treated RBCs

  9. A pyrene-benzthiazolium conjugate portraying aggregation induced emission, a ratiometric detection and live cell visualization of HSO_3"−

    International Nuclear Information System (INIS)

    Diwan, Uzra; Kumar, Virendra; Mishra, Rakesh K.; Rana, Nishant Kumar; Koch, Biplob; Singh, Manish Kumar; Upadhyay, K.K.

    2016-01-01

    The present study deals with the photophysical property of a pyrene-benzthiazolium conjugate R1, as a strong intramolecular charge transfer (ICT) probe exhibiting long wavelength emission in the red region. Unlike traditional planar polyaromatic hydrocarbons whose aggregation generally quenches the light emission, the pyrene based R1 was found to display aggregation-induced emission (AIE) property along with simultaneous increase in its quantum yield upon increasing the water content of the medium. The R1 exhibits high specificity towards HSO_3"−/SO_3"2"− by interrupting its own ICT producing there upon a large ratiometric blue shift of ∼220 nm in its emission spectrum. The lowest detection limit for the above measurement was found to be 8.90 × 10"−"8 M. The fluorescent detection of HSO_3"− was also demonstrated excellently by test paper strip and silica coated TLC plate incorporating R1. The live cell imaging of HSO_3"− through R1 in HeLa cells was studied using fluorescence microscopic studies. The particle size and morphological features of R1 and R1-HSO_3"− aggregates in aqueous solution were characterized by DLS along with SEM analysis.- Highlights: • A pyrene-benzthiazolium conjugate probe (R1) itself showed interesting phenomenon of an aggregation-induced emission (AIE). • R1 emits in the red channel and effectively utilized as a colorimetric and ratiometric fluorescent sensor for HSO_3"−. • The nano-dimensional spherical particles of R1 got enlarged upon its interaction with the HSO_3"−. • R1 can efficiently stain HSO_3"− in live cells and can be used for the on-spot detection of the same.

  10. 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

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

    International Nuclear Information System (INIS)

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

    2016-01-01

    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

  12. 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)

  13. Kinetics of heat damage autologous red blood cells. Mechanism of clearance from blood

    Energy Technology Data Exchange (ETDEWEB)

    Peters, A.M.; Ryan, P.F.J.; Klonizakis, I.; Elkon, K.B.; Lewis, S.M.; Hughes, G.R.V.; Lavender, J.P. (Hammersmith Hospital, London (UK))

    1982-01-01

    The kinetics of radiolabelled heat damage red cell (HDRBC) distribution have been studied in humans using a gamma camera, and compared with the kinetics of other blood cells. Liver uptake of /sup 111/In labelled HDRBC was completed within about 10 min of injection; splenic uptake was biphasic with a half time of about 5 min over the first 20 min in following injection, and a later half time much longer than this. Activity initially present in the lung fields cleared within 24 h. The rate constant of liver uptake of sup(99m)Tc labelled HDRBC and of /sup 111/In labelled platelets were very similar; the rate constants of splenic uptake of these 2 particles were also very similar up to about 20 min following injection when the splenic platelet levels became constant and the HDRBC level continued to slowly rise. Splenic uptake and blood clearance of red cells coated with IgG (IgG-RBC), in contrast to HDRBC, were monoexponential. It was concluded that: (1) the blood clearance of HDRBC was due to pooling within, and to irreversible extraction by, the spleen; (2) liver uptake of HDRBC, which was irreversible, was completed within 10 min of injection; (3) IgG-RBC clearance was due to irreversible extraction by the spleen; (4) HDRBC uptake in the lung was unrelated to reticuloendothelial function, and represented prolonged transit through the lung microvasculature.

  14. 76 FR 11491 - Advisory Council on Blood Stem Cell Transplantation; Request for Nominations for Voting Members

    Science.gov (United States)

    2011-03-02

    ... transplantation, Program priorities, research priorities, and the scope and design of the Stem Cell Therapeutic... Council on Blood Stem Cell Transplantation; Request for Nominations for Voting Members AGENCY: Health... on Blood Stem Cell Transplantation. The Advisory Council on Blood Stem Cell Transplantation was...

  15. Hairy-cell leukemia: a rare blood disorder in Asia.

    Science.gov (United States)

    Josephine, F P; Nissapatorn, V

    2006-01-01

    We report a 68-year-old Indian man who was referred to the Hematology Unit for investigation for thrombocytopenia, an incidental finding during a pre-operative screening for prostatectomy. Physical examination was unremarkable. There was no splenomegaly, hepatomegaly or lymphadenopathy. Complete blood counts showed normal hemoglobin and total white cell count with moderate thrombocytopenia. Hairy-cell leukemia was diagnosed based on peripheral blood film, bone-marrow aspirate and trephine biopsy findings, supported by immunophenotyping results by flow cytometry. The purpose of this report is to create awareness of this uncommon presentation and to emphasize that a single-lineage cytopenia or absence of splenomegaly does not exclude the diagnosis of hairy-cell leukemia. Careful attention to morphological detail is important for early diagnosis, especially when low percentages of "hairy" cells are present in the peripheral blood and bone marrow. Early diagnosis is important to ensure that patients obtain maximum benefit from the newer therapeutic agents that have greatly improved the prognosis in this rare disorder.

  16. 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.

  17. 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.

  18. MRP4 knockdown enhances migration, suppresses apoptosis, and produces aggregated morphology in human retinal vascular endothelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Tagami, Mizuki [Department of Surgery Related, Division of Ophthalmology, Kobe University Graduate School of Medicine, 7-5-2 Kusunoki-cho, Chuo-ku, Kobe 650-0017 (Japan); Kusuhara, Sentaro, E-mail: kusu@med.kobe-u.ac.jp [Department of Surgery Related, Division of Ophthalmology, Kobe University Graduate School of Medicine, 7-5-2 Kusunoki-cho, Chuo-ku, Kobe 650-0017 (Japan); Imai, Hisanori [Department of Surgery Related, Division of Ophthalmology, Kobe University Graduate School of Medicine, 7-5-2 Kusunoki-cho, Chuo-ku, Kobe 650-0017 (Japan); Uemura, Akiyoshi [Department of Surgery Related, Division of Ophthalmology, Kobe University Graduate School of Medicine, 7-5-2 Kusunoki-cho, Chuo-ku, Kobe 650-0017 (Japan); Department of Vascular Biology, Kobe University Graduate School of Medicine, 7-5-2 Kusunoki-cho, Chuo-ku, Kobe 650-0017 (Japan); Honda, Shigeru; Tsukahara, Yasutomo; Negi, Akira [Department of Surgery Related, Division of Ophthalmology, Kobe University Graduate School of Medicine, 7-5-2 Kusunoki-cho, Chuo-ku, Kobe 650-0017 (Japan)

    2010-10-01

    Research highlights: {yields} Exogenous VEGF decreases MRP4 expression in a dose-dependent manner. {yields} MRP4 knockdown leads to enhanced cell migration. {yields} MRP4 knockdown suppresses caspase-3-mediated cell apoptosis. {yields} MRP4 knockdown produces cell assembly and cell aggregation. -- Abstract: The multidrug resistance protein (MRP) MRP4/ABCC4 is an ATP-binding cassette transporter that actively effluxes endogenous and xenobiotic substrates out of cells. In the rodent retina, Mrp4 mRNA and protein are exclusively expressed in vascular endothelial cells, but the angiogenic properties of Mrp4 are poorly understood so far. This study aims to explore the angiogenic properties of MRP4 in human retinal microvascular endothelial cells (HRECs) utilizing the RNA interference (RNAi) technique. MRP4 expression was decreased at the mRNA and protein levels after stimulation with exogenous vascular endothelial growth factor in a dose-dependent manner. RNAi-mediated MRP4 knockdown in HRECs do not affect cell proliferation but enhances cell migration. Moreover, cell apoptosis induced by serum starvation was less prominent in MRP4 siRNA-treated HRECs as compared to control siRNA-treated HRECs. In a Matrigel-based tube-formation assay, although MRP4 knockdown did not lead to a significant change in the total tube length, MRP4 siRNA-treated HRECs assembled and aggregated into a massive tube-like structure, which was not observed in control siRNA-treated HRECs. These results suggest that MRP4 is uniquely involved in retinal angiogenesis.

  19. Effect of Aggregated β-Amyloid (1-42 on Synaptic Plasticity of Hippocampal Dentate Gyrus Granule Cells in Vivo

    Directory of Open Access Journals (Sweden)

    Shirin Babri

    2012-12-01

    Full Text Available Introduction: Alzheimer’s disease (AD is a common neurodegenerative disorder in elderly people with an impairment of cognitive decline and memory loss. β-amyloid (Aβ as a potent neurotoxic peptide has a pivotal role in the pathogenesis of AD. This disease begins with impairment in synaptic functions before developing into later neuro­degeneration and neuronal loss. The aim of this study was to evaluate the synaptic plasticity and electrophysiological function of granule cells in hippocampal dentate gyrus (DG after intracerebroventricular (i.c.v. administration of aggregated Aβ (1-42 peptide in vivo. Methods: Animals were divided to control and Aβ (1-42 groups. Long-term potentia­tion (LTP in perforant path-DG synapses was assessed in order to investigate the effect of aggregated Aβ (1-42 on synaptic plasticity. Field excitatory post-synaptic potential (fEPSP slope and population spike (PS amplitude were measured. Results: Administration of Aβ (1-42 significantly decreased fEPSP slope and PS amplitude in Aβ (1-42 group comparing with the control group and had no effect on baseline activity of neurons. Conclusion: The present study indicates that administration of aggregated form of Aβ (1-42 into the lateral ventricle effectively inhibits LTP in granular cells of the DG in hippocampus in vivo.

  20. Inclusion of aggregation effect to evaluate the performance of organic dyes in dye-sensitized solar cells

    Science.gov (United States)

    Sun, Kenan; Zhang, Weiyi; Heng, Panpan; Wang, Li; Zhang, Jinglai

    2018-05-01

    Two new indoline-based D-A-π-A dyes, D3F and D3F2 (see Scheme 1), are developed on the basis of the reported D3 by insertion of one or two F atoms on benzothiadiazole group. Our central aim is to explore high-efficiency organic dyes applied in dye-sensitized solar cells by inclusion of a simple group rather than by employment of new complicated groups. The performance of two new designed organic dyes, D3F and D3F2, is compared with that of D3 from various aspects including absorption spectrum, light harvesting efficiency, driving force, and open-circuit voltage. Besides the isolated dye, the interfacial property between dye and TiO2 surface is studied. D3F and D3F2 do not show absolute superiority than D3 not only for the isolated dyes but also for the monomeric adsorption system. However, D3F and D3F2 would effectively reduce the influence of aggregation resulting in the much smaller intermolecular electronic coupling. Although the aggregation has attracted much attention recently, it is studied alone in most of studies. To comprehensively evaluate the performance of dye-sensitized solar cells, it is necessary to consider aggregation along with electron injection time from dye into TiO2 rather than only static items, such as, band gap and absorption region.

  1. From the test tube to the cell: exploring the folding and aggregation of a beta-clam protein.

    Science.gov (United States)

    Ignatova, Zoya; Krishnan, Beena; Bombardier, Jeffrey P; Marcelino, Anna Marie C; Hong, Jiang; Gierasch, Lila M

    2007-01-01

    A crucial challenge in present biomedical research is the elucidation of how fundamental processes like protein folding and aggregation occur in the complex environment of the cell. Many new physico-chemical factors like crowding and confinement must be considered, and immense technical hurdles must be overcome in order to explore these processes in vivo. Understanding protein misfolding and aggregation diseases and developing therapeutic strategies to these diseases demand that we gain mechanistic insight into behaviors and misbehaviors of proteins as they fold in vivo. We have developed a fluorescence approach using FlAsH labeling to study the thermodynamics of folding of a model beta-rich protein, cellular retinoic acid binding protein (CRABP) in Escherichia coli cells. The labeling approach has also enabled us to follow aggregation of a modified version of CRABP and chimeras between CRABP and huntingtin exon 1 with its glutamine repeat tract. In this article, we review our recent results using FlAsH labeling to study in-vivo folding and present new observations that hint at fundamental differences between the thermodynamics and kinetics of protein folding in vivo and in vitro.

  2. Resveratrol, Acetyl-Resveratrol, and Polydatin Exhibit Antigrowth Activity against 3D Cell Aggregates of the SKOV-3 and OVCAR-8 Ovarian Cancer Cell Lines

    OpenAIRE

    Hogg, Simon J.; Chitcholtan, Kenny; Hassan, Wafaa; Sykes, Peter H.; Garrill, Ashley

    2015-01-01

    Resveratrol has aroused significant scientific interest as it has been claimed that it exhibits a spectrum of health benefits. These include effects as an anti-inflammatory and an antitumour compound. The purpose of this study was to investigate and compare any potential antigrowth effects of resveratrol and two of its derivatives, acetyl-resveratrol and polydatin, on 3D cell aggregates of the EGFR/Her-2 positive and negative ovarian cancer cell lines SKOV-3 and OVCAR-8, respectively. Results...

  3. Characterization of glucocerebrosidase in peripheral blood cells and cultured blastoid cells

    NARCIS (Netherlands)

    Aerts, J. M.; Heikoop, J.; van Weely, S.; Donker-Koopman, W. E.; Barranger, J. A.; Tager, J. M.; Schram, A. W.

    1988-01-01

    We have characterized glucocerebrosidase in various cell types of peripheral blood of control subjects and in cultured human blastoid cells. The intracellular level of glucocerebrosidase in cultured blastoid cells (10-30 nmol substrate hydrolyzed/h.mg protein) resembles closely values observed for

  4. Homotypic aggregation of human cell lines by HLA class II-, class Ia- and HLA-G-specific monoclonal antibodies

    DEFF Research Database (Denmark)

    Odum, Niels; Ledbetter, J A; Martin, P

    1991-01-01

    Major histocompatibility complex (MHC) class II molecules have been implicated in cell adhesion in two ways. In addition to the well-established role of class II antigens in low-affinity adhesion provided by interactions between class II and CD4, recent data indicated that class II may also induce...... adhesion between T and B cells by activating the CD18/CD11a (LFA-1) adhesion pathway. Here we report that monoclonal antibodies (mAb) against HLA-DR (L243, p4.1, HB10a, VI15) and certain broad class II reacting mAb (TU35, TU39), but not anti-DQ (TU22, Leu-10) mAb, induced homotypic aggregation of human...... class II-positive monocytic (I937) and T leukemic (HUT78) tumor cell lines and Epstein-Barr virus (EBV) transformed B-lymphoid cell lines (EBV-LCL). Class II-negative cell lines (U-937 and the EBV-LCL mutant line 616) were not induced to aggregate. An HLA-G-transfected EBV-LCL, 221-AGN...

  5. Novel Cell Preservation Technique to Extend Bovine In Vitro White Blood Cell Viability.

    Directory of Open Access Journals (Sweden)

    Emilie L Laurin

    Full Text Available Although cell-mediated immunity based diagnostics can be integral assays for early detection of various diseases of dairy cows, processing of blood samples for these tests is time-sensitive, often within 24 hours of collection, to maintain white blood cell viability. Therefore, to improve utility and practicality of such assays, the objective of this study was to assess the use of a novel white blood cell preservation technology in whole bovine blood. Blood samples from ten healthy cows were each divided into an unpreserved control sample and a test sample preserved with commercially-available cell transport medium. Samples were maintained at room temperature and stimulated with the mitogens pokeweed and concanavalinA, as well as with interleukin-12 p40. Stimulation was completed on days 1, 5, and 8 post-sampling. Viability of white blood cells was assessed through interferon gamma production determined with a commercial enzyme linked immunosorbent assay. In addition, mononuclear cell viability was assessed with propidium iodide flow cytometry. Greater interferon gamma production was observed on days 5 and 8 post-collection in preserved samples, with both pokeweed and concanavalinA stimulating positive interferon gamma production on day 5 post-collection. A greater proportion of the amount of interferon gamma produced on day 1 continued to be produced on days 5 and 8 post-collection with concanavalinA stimulation (with or without interleukin 12 as compared to pokeweed stimulation. Additionally, viable mononuclear cells were still present at eight days post-collection, with a higher mean proportion detected at days 5 and 8 in all stimulated preserved samples. This practical and simple method to extend in vitro white blood cell viability could benefit the efficient utilization of cell-based blood tests in ruminants.

  6. Concise review: stem cell-based approaches to red blood cell production for transfusion.

    Science.gov (United States)

    Shah, Siddharth; Huang, Xiaosong; Cheng, Linzhao

    2014-03-01

    Blood transfusion is a common procedure in modern medicine, and it is practiced throughout the world; however, many countries report a less than sufficient blood supply. Even in developed countries where the supply is currently adequate, projected demographics predict an insufficient supply as early as 2050. The blood supply is also strained during occasional widespread disasters and crises. Transfusion of blood components such as red blood cells (RBCs), platelets, or neutrophils is increasingly used from the same blood unit for multiple purposes and to reduce alloimmune responses. Even for RBCs and platelets lacking nuclei and many antigenic cell-surface molecules, alloimmunity could occur, especially in patients with chronic transfusion requirements. Once alloimmunization occurs, such patients require RBCs from donors with a different blood group antigen combination, making it a challenge to find donors after every successive episode of alloimmunization. Alternative blood substitutes such as synthetic oxygen carriers have so far proven unsuccessful. In this review, we focus on current research and technologies that permit RBC production ex vivo from hematopoietic stem cells, pluripotent stem cells, and immortalized erythroid precursors.

  7. 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

  8. 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.

  9. 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.

  10. Blood cell labeling with technetium-99m, (3)

    International Nuclear Information System (INIS)

    Uchida, Tatsumi; Akizuki, Tsuyoshi; Tanaka, Tetsugoro; Yui, Tokuo; Miura, Nobuo

    1978-01-01

    Spleen scintigraphy was performed by the use of sup(99m)Tc-labeled red blood cells which were prepared with a kit (TCK-11 produced by CIS) and were damaged by heating for 15 min at 49.0 +- 0.5 0 C or damaged chemically by treating with bromomerculi hydroxy propane (BMHP) 1.5 mg/2 ml of blood. The images obtained by scanner and scintillation camera were both favorable, and the author decided that this method is applicable to clinical spleen scintigraphy. The spleen scintigraphy with sup(99m)Tc-labeled red blood cells has many merits such as it gives a less exposure dose to patients under the examination so that it makes capable of repeated examinations, it uses a less volume of blood for labeling, and the procedure is not so complicated compared with the usual methods of 51 Cr-heating or 203 Hg- (or 197 Hg-) MHP. Therefore, this method is preferable to the other usual methods. (Ueda, J.)

  11. 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

  12. Red blood cell aging markers during storage in citrate-phosphate-dextrose-saline-adenine-glucose-mannitol.

    Science.gov (United States)

    Antonelou, Marianna H; Kriebardis, Anastasios G; Stamoulis, Konstantinos E; Economou-Petersen, Effrosini; Margaritis, Lukas H; Papassideri, Issidora S

    2010-02-01

    It has been suggested that red blood cell (RBC) senescence is accelerated under blood bank conditions, although neither protein profile of RBC aging nor the impact of additive solutions on it have been studied in detail. RBCs and vesicles derived from RBCs in both citrate-phosphate-dextrose (CPD)-saline-adenine-glucose-mannitol (SAGM) and citrate-phosphate-dextrose-adenine (CPDA) were evaluated for the expression of cell senescence markers (vesiculation, protein aggregation, degradation, activation, oxidation, and topology) through immunoblotting technique and immunofluorescence or immunoelectron microscopy study. A group of cellular stress proteins exhibited storage time- and storage medium-related changes in their membrane association and exocytosis. The extent, the rate, and the expression of protein oxidation, Fas oligomerization, caspase activation, and protein modifications in Band 3, hemoglobin, and immunoglobulin G were less conspicuous and/or exhibited significant time retardation under storage in CPD-SAGM, compared to the CPDA storage. There was evidence for the localization of activated caspases near to the membrane of both cells and vesicles. We provide circumstantial evidence for a lower protein oxidative damage in CPD-SAGM-stored RBCs compared to the CPDA-stored cells. The different expression patterns of the senescence markers in the RBCs seem to be accordingly related to the oxidative stress management of the cells. We suggest that the storage of RBCs in CPD-SAGM might be more alike the in vivo RBC aging process, compared to storage in CPDA, since it is characterized by a slower stimulation of the recognition signaling pathways that are already known to trigger the erythrophagocytosis of senescent RBCs.

  13. 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...... research and confirms new sequencing technology as a paradigm for large-scale epigenomics studies....

  14. 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.

  15. 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

  16. Amyotrophic Lateral Sclerosis Multiprotein Biomarkers in Peripheral Blood Mononuclear Cells

    OpenAIRE

    Nardo, Giovanni; Pozzi, Silvia; Pignataro, Mauro; Lauranzano, Eliana; Spano, Giorgia; Garbelli, Silvia; Mantovani, Stefania; Marinou, Kalliopi; Papetti, Laura; Monteforte, Marta; Torri, Valter; Paris, Luca; Bazzoni, Gianfranco; Lunetta, Christian; Corbo, Massimo

    2011-01-01

    Background 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. Methodology/Principal Findings We used a two-dimensional difference in gel electrophoresis approach to identify in easily accessible clinical samples, peripheral blood mononuclear cells (PBMC), a panel...

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

    OpenAIRE

    B. T. Dzumabaeva; L. S. Birjukova; L. B. Kaplanskaya; D. P. Maksimov

    2011-01-01

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

  18. When Blood Cells Bend: Understanding Sickle Cell Disease

    Science.gov (United States)

    ... risk of having a child with sickle cell anemia and are planning to have children, ask your health care professional about genetic counseling. ... to manage pain. Make sure babies and young children get needed antibiotics and routine vaccinations to ... Nicholas NIH Office of Communications and ...

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

    Science.gov (United States)

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

    2016-01-01

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

  20. 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.

  1. 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

  2. Red Blood Cell Antibody Screen: MedlinePlus Lab Test Information

    Science.gov (United States)

    ... medlineplus.gov/labtests/redbloodcellantibodyscreen.html Red Blood Cell Antibody Screen To use the sharing features on this page, please enable JavaScript. What is an RBC Antibody Screen? An RBC (red blood cell) antibody screen ...

  3. Blood cell mitochondrial DNA content and premature ovarian aging.

    Directory of Open Access Journals (Sweden)

    Marco Bonomi

    Full Text Available 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.

  4. 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

  5. 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.

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

    DEFF Research Database (Denmark)

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

    2017-01-01

    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...

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. 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

  12. 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

  13. Development and testing of a new disposable sterile device for labelling white blood cells

    NARCIS (Netherlands)

    Signore, A.; Glaudemans, A. W. J. M.; Malviya, G.; Lazzeri, E.; Prandini, N.; Viglietti, A. L.; De Vries, E. F. J.; Dierckx, R. A. J. O.

    Aim. White blood cell (WBC) labelling requires isolation of cells from patient's blood under sterile conditions using sterile materials, buffers and disposables under good manufacturing practice (GMP) conditions. Till now, this limited the use of white blood cell scintigraphy (WBC-S) only to well

  14. Effects of hydroxyurea on blood rheology in sickle cell anemia: A two-years follow-up study.

    Science.gov (United States)

    Lemonne, Nathalie; Möckesch, Berenike; Charlot, Keyne; Garnier, Yohann; Waltz, Xavier; Lamarre, Yann; Antoine-Jonville, Sophie; Etienne-Julan, Maryse; Hardy-Dessources, Marie-Dominique; Romana, Marc; Connes, Philippe

    2017-01-01

    The aim of the present study was to test the effects of hydroxyurea (HU) therapy on clinical, hematological and hemorheological parameters in adult patients with sickle cell anemia (SCA). Hematological and hemorheological parameters were measured in 28 SCA patients before HU therapy (i.e., baseline) and at 6, 12 and 24 months of treatment. RBC deformability was determined by ektacytometry at 30 Pa. RBC aggregation properties were investigated by light-backscatter method. Blood viscosity was measured at 225 s-1 by a cone-plate viscometer. The rates of vaso-occlusive crises and acute chest syndrome were lower at 1 and 2 years of HU therapy compared to baseline. The proportion of patients with leg ulcers tended to decrease after 2 years of treatment. Hemoglobin oxygen saturation improved with HU therapy. HU therapy induced a decrease of platelet and white blood cell counts and a rise in fetal hemoglobin level and mean cell volume. While hemoglobin concentrations increased under HU, blood viscosity remained unchanged all along the study. RBC deformability increased over baseline values at 6 months of HU therapy and continued to rise until the end of the follow-up period. In conclusion, the improvement in RBC deformability probably compensates the increase of hemoglobin on blood viscosity and participates to the improvement of the clinical status of patients.

  15. 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.

  16. Aurora-A overexpression enhances cell-aggregation of Ha-ras transformants through the MEK/ERK signaling pathway

    International Nuclear Information System (INIS)

    Tseng, Ya-Shih; Lee, Jenq-Chang; Huang, Chi-Ying F; Liu, Hsiao-Sheng

    2009-01-01

    Overexpression of Aurora-A and mutant Ras (Ras V12 ) together has been detected in human bladder cancer tissue. However, it is not clear whether this phenomenon is a general event or not. Although crosstalk between Aurora-A and Ras signaling pathways has been reported, the role of these two genes acting together in tumorigenesis remains unclear. Real-time PCR and sequence analysis were utilized to identify Ha- and Ki-ras mutation (Gly -> Val). Immunohistochemistry staining was used to measure the level of Aurora-A expression in bladder and colon cancer specimens. To reveal the effect of overexpression of the above two genes on cellular responses, mouse NIH3T3 fibroblast derived cell lines over-expressing either Ras V12 and wild-type Aurora-A (designated WT) or Ras V12 and kinase-inactivated Aurora-A (KD) were established. MTT and focus formation assays were conducted to measure proliferation rate and focus formation capability of the cells. Small interfering RNA, pharmacological inhibitors and dominant negative genes were used to dissect the signaling pathways involved. Overexpression of wild-type Aurora-A and mutation of Ras V12 were detected in human bladder and colon cancer tissues. Wild-type Aurora-A induces focus formation and aggregation of the Ras V12 transformants. Aurora-A activates Ral A and the phosphorylation of AKT as well as enhances the phosphorylation of MEK, ERK of WT cells. Finally, the Ras/MEK/ERK signaling pathway is responsible for Aurora-A induced aggregation of the Ras V12 transformants. Wild-type-Aurora-A enhances focus formation and aggregation of the Ras V12 transformants and the latter occurs through modulating the Ras/MEK/ERK signaling pathway

  17. Red blood cell transfusion for people undergoing hip fracture surgery.

    Science.gov (United States)

    Brunskill, Susan J; Millette, Sarah L; Shokoohi, Ali; Pulford, E C; Doree, Carolyn; Murphy, Michael F; Stanworth, Simon

    2015-04-21

    The incidence of hip fracture is increasing and it is more common with increasing age. Surgery is used for almost all hip fractures. Blood loss occurs as a consequence of both the fracture and the surgery and thus red blood cell transfusion is frequently used. However, red blood cell transfusion is not without risks. Therefore, it is important to identify the evidence for the effective and safe use of red blood cell transfusion in people with hip fracture. To assess the effects (benefits and harms) of red blood cell transfusion in people undergoing surgery for hip fracture. We searched the Cochrane Bone, Joint and Muscle Trauma Group Specialised Register (31 October 2014), the Cochrane Central Register of Controlled Trials (The Cochrane Library, 2014, Issue 10), MEDLINE (January 1946 to 20 November 2014), EMBASE (January 1974 to 20 November 2014), CINAHL (January 1982 to 20 November 2014), British Nursing Index Database (January 1992 to 20 November 2014), the Systematic Review Initiative's Transfusion Evidence Library, PubMed for e-publications, various other databases and ongoing trial registers. Randomised controlled trials comparing red blood cell transfusion versus no transfusion or an alternative to transfusion, different transfusion protocols or different transfusion thresholds in people undergoing surgery for hip fracture. Three review authors independently assessed each study's risk of bias and extracted data using a study-specific form. We pooled data where there was homogeneity in the trial comparisons and the timing of outcome measurement. We used GRADE criteria to assess the quality (low, moderate or high) of the evidence for each outcome. We included six trials (2722 participants): all compared two thresholds for red blood cell transfusion: a 'liberal' strategy to maintain a haemoglobin concentration of usually 10 g/dL versus a more 'restrictive' strategy based on symptoms of anaemia or a lower haemoglobin concentration, usually 8 g/dL. The exact

  18. Zeroing in on red blood cell unit expiry.

    Science.gov (United States)

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

    2017-12-01

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

  19. 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.

  20. 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.

  1. In vitro generation of three-dimensional substrate-adherent embryonic stem cell-derived neural aggregates for application in animal models of neurological disorders.

    Science.gov (United States)

    Hargus, Gunnar; Cui, Yi-Fang; Dihné, Marcel; Bernreuther, Christian; Schachner, Melitta

    2012-05-01

    In vitro-differentiated embryonic stem (ES) cells comprise a useful source for cell replacement therapy, but the efficiency and safety of a translational approach are highly dependent on optimized protocols for directed differentiation of ES cells into the desired cell types in vitro. Furthermore, the transplantation of three-dimensional ES cell-derived structures instead of a single-cell suspension may improve graft survival and function by providing a beneficial microenvironment for implanted cells. To this end, we have developed a new method to efficiently differentiate mouse ES cells into neural aggregates that consist predominantly (>90%) of postmitotic neurons, neural progenitor cells, and radial glia-like cells. When transplanted into the excitotoxically lesioned striatum of adult mice, these substrate-adherent embryonic stem cell-derived neural aggregates (SENAs) showed significant advantages over transplanted single-cell suspensions of ES cell-derived neural cells, including improved survival of GABAergic neurons, increased cell migration, and significantly decreased risk of teratoma formation. Furthermore, SENAs mediated functional improvement after transplantation into animal models of Parkinson's disease and spinal cord injury. This unit describes in detail how SENAs are efficiently derived from mouse ES cells in vitro and how SENAs are isolated for transplantation. Furthermore, methods are presented for successful implantation of SENAs into animal models of Huntington's disease, Parkinson's disease, and spinal cord injury to study the effects of stem cell-derived neural aggregates in a disease context in vivo.

  2. 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.

  3. 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

  4. 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

  5. Resting blood lactate in individuals with sickle cell disease

    Directory of Open Access Journals (Sweden)

    Jefferson Petto

    2011-02-01

    Full Text Available 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. 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.

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

    Science.gov (United States)

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

    2016-08-16

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

  7. Extracorporeal irradiation of dog blood: the effects of a radiostrontium irradiator on blood stem cells (CFU-C)

    Energy Technology Data Exchange (ETDEWEB)

    Szemere, P.; Fliedner, T.M.; Nothdurft, W.; Breitig, D.

    1982-07-01

    The radiation sensitivity of dog blood stem cells was measured in vitro and in an extracorporeal circulation passing through a radiation field. It was established that the calculated D/sub 0/ was as low as 0.45 Gy. Investigating the cell killing rate in our equipment (Buchler type /sup 90/Sr device for extracorporeal irradiation), we found an overkill situation; the dose delivered was in excess of that which would be required for the total eradication of all stem cells in the peripheral blood passing through the radiation field. Various other types of devices used for extracorporeal irradiation of blood are also reviewed.

  8. The Effect of Disinfection on Viability and Function of Baboon Red Blood Cells and Platelets

    Science.gov (United States)

    1997-07-11

    blood cells was evaluated by their ability to transport oxygen as assessed by measurement of 2,3 diphosphoglycerate (DPG)14 and red blood cell p50,15...Blood collected from the bleeding time site (referred to as "shed blood") had a significantly reduced thromboxane A2 level . The ability of the...preserved or treated platelets to increase the shed blood thromboxane A2 level and reduce the 8; extended bleeding time is the measure of their

  9. 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.

  10. 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.

  11. An indicator cell assay for blood-based diagnostics.

    Directory of Open Access Journals (Sweden)

    Samuel A Danziger

    Full Text Available We have established proof of principle for the Indicator Cell Assay Platform™ (iCAP™, a broadly applicable tool for blood-based diagnostics that uses specifically-selected, standardized cells as biosensors, relying on their innate ability to integrate and respond to diverse signals present in patients' blood. To develop an assay, indicator cells are exposed in vitro to serum from case or control subjects and their global differential response patterns are used to train reliable, disease classifiers based on a small number of features. In a feasibility study, the iCAP detected pre-symptomatic disease in a murine model of amyotrophic lateral sclerosis (ALS with 94% accuracy (p-Value = 3.81E-6 and correctly identified samples from a murine Huntington's disease model as non-carriers of ALS. Beyond the mouse model, in a preliminary human disease study, the iCAP detected early stage Alzheimer's disease with 72% cross-validated accuracy (p-Value = 3.10E-3. For both assays, iCAP features were enriched for disease-related genes, supporting the assay's relevance for disease research.

  12. [Stem and progenitor cells in biostructure of blood vessel walls].

    Science.gov (United States)

    Korta, Krzysztof; Kupczyk, Piotr; Skóra, Jan; Pupka, Artur; Zejler, Paweł; Hołysz, Marcin; Gajda, Mariusz; Nowakowska, Beata; Barć, Piotr; Dorobisz, Andrzej T; Dawiskiba, Tomasz; Szyber, Piotr; Bar, Julia

    2013-09-18

    Development of vascular and hematopoietic systems during organogenesis occurs at the same time. During vasculogenesis, a small part of cells does not undergo complete differentiation but stays on this level, "anchored" in tissue structures described as stem cell niches. The presence of blood vessels within tissue stem cell niches is typical and led to identification of niches and ensures that they are functioning. The three-layer biostructure of vessel walls for artery and vein, tunica: intima, media and adventitia, for a long time was defined as a mechanical barrier between vessel light and the local tissue environment. Recent findings from vascular biology studies indicate that vessel walls are dynamic biostructures, which are equipped with stem and progenitor cells, described as vascular wall-resident stem cells/progenitor cells (VW-SC/PC). Distinct zones for vessel wall harbor heterogeneous subpopulations of VW-SC/PC, which are described as "subendothelial or vasculogenic zones". Recent evidence from in vitro and in vivo studies show that prenatal activity of stem and progenitor cells is not only limited to organogenesis but also exists in postnatal life, where it is responsible for vessel wall homeostasis, remodeling and regeneration. It is believed that VW-SC/PC could be engaged in progression of vascular disorders and development of neointima. We would like to summarize current knowledge about mesenchymal and progenitor stem cell phenotype with special attention to distribution and biological properties of VW-SC/PC in biostructures of intima, media and adventitia niches. It is postulated that in the near future, niches for VW-SC/PC could be a good source of stem and progenitor cells, especially in the context of vessel tissue bioengineering as a new alternative to traditional revascularization therapies.

  13. Stem and progenitor cells in biostructure of blood vessel walls

    Directory of Open Access Journals (Sweden)

    Krzysztof Korta

    2013-09-01

    Full Text Available Development of vascular and hematopoietic systems during organogenesis occurs at the same time. During vasculogenesis, a small part of cells does not undergo complete differentiation but stays on this level, “anchored” in tissue structures described as stem cell niches. The presence of blood vessels within tissue stem cell niches is typical and led to identification of niches and ensures that they are functioning. The three-layer biostructure of vessel walls for artery and vein, tunica: intima, media and adventitia, for a long time was defined as a mechanical barrier between vessel light and the local tissue environment. Recent findings from vascular biology studies indicate that vessel walls are dynamic biostructures, which are equipped with stem and progenitor cells, described as vascular wall-resident stem cells/progenitor cells (VW-SC/PC. Distinct zones for vessel wall harbor heterogeneous subpopulations of VW-SC/PC, which are described as “subendothelial or vasculogenic zones”. Recent evidence from in vitro and in vivo studies show that prenatal activity of stem and progenitor cells is not only limited to organogenesis but also exists in postnatal life, where it is responsible for vessel wall homeostasis, remodeling and regeneration. It is believed that VW-SC/PC could be engaged in progression of vascular disorders and development of neointima. We would like to summarize current knowledge about mesenchymal and progenitor stem cell phenotype with special attention to distribution and biological properties of VW-SC/PC in biostructures of intima, media and adventitia niches. It is postulated that in the near future, niches for VW-SC/PC could be a good source of stem and progenitor cells, especially in the context of vessel tissue bioengineering as a new alternative to traditional revascularization therapies.

  14. Red blood cell-derived microparticles isolated from blood units initiate and propagate thrombin generation.

    Science.gov (United States)

    Rubin, Olivier; Delobel, Julien; Prudent, Michel; Lion, Niels; Kohl, Kid; Tucker, Erik I; Tissot, Jean-Daniel; Angelillo-Scherrer, Anne

    2013-08-01

    Red blood cell-derived microparticles (RMPs) are small phospholipid vesicles shed from RBCs in blood units, where they accumulate during storage. Because microparticles are bioactive, it could be suggested that RMPs are mediators of posttransfusion complications or, on the contrary, constitute a potential hemostatic agent. This study was performed to establish the impact on coagulation of RMPs isolated from blood units. Using calibrated automated thrombography, we investigated whether RMPs affect thrombin generation (TG) in plasma. We found that RMPs were not only able to increase TG in plasma in the presence of a low exogenous tissue factor (TF) concentration, but also to initiate TG in plasma in absence of exogenous TF. TG induced by RMPs in the absence of exogenous TF was neither affected by the presence of blocking anti-TF nor by the absence of Factor (F)VII. It was significantly reduced in plasma deficient in FVIII or F IX and abolished in FII-, FV-, FX-, or FXI-deficient plasma. TG was also totally abolished when anti-XI 01A6 was added in the sample. Finally, neither Western blotting, flow cytometry, nor immunogold labeling allowed the detection of traces of TF antigen. In addition, RMPs did not comprise polyphosphate, an important modulator of coagulation. Taken together, our data show that RMPs have FXI-dependent procoagulant properties and are able to initiate and propagate TG. The anionic surface of RMPs might be the site of FXI-mediated TG amplification and intrinsic tenase and prothrombinase complex assembly. © 2012 American Association of Blood Banks.

  15. Disulfide scrambling in superoxide dismutase 1 reduces its cytotoxic effect in cultured cells and promotes protein aggregation.

    Directory of Open Access Journals (Sweden)

    Lina Leinartaitė

    Full Text Available Mutations in the gene coding for superoxide dismutase 1 (SOD1 are associated with familiar forms of the neurodegenerative disease amyotrophic lateral sclerosis (ALS. These mutations are believed to result in a "gain of toxic function", leading to neuronal degeneration. The exact mechanism is still unknown, but misfolding/aggregation events are generally acknowledged as important pathological events in this process. Recently, we observed that demetallated apoSOD1, with cysteine 6 and 111 substituted for alanine, is toxic to cultured neuroblastoma cells. This toxicity depended on an intact, high affinity Zn(2+ site. It was therefor contradictory to discover that wild-type apoSOD1 was not toxic, despite of its high affinity for Zn(2+. This inconsistency was hypothesized to originate from erroneous disulfide formation involving C6 and C111. Using high resolution non-reducing SDS-PAGE, we have in this study demonstrated that the inability of wild-type apoSOD1 to cause cell death stems from formation of non-native intra-molecular disulfides. Moreover, monomeric apoSOD1 variants capable of such disulfide scrambling aggregated into ThT positive oligomers under physiological conditions without agitation. The oligomers were stabilized by inter-molecular disulfides and morphologically resembled what has in other neurodegenerative diseases been termed protofibrils. Disulfide scrambling thus appears to be an important event for misfolding and aggregation of SOD1, but may also be significant for protein function involving cysteines, e.g. mitochondrial import and copper loading.

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

    Directory of Open Access Journals (Sweden)

    Serena Valsami

    2017-03-01

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

  17. Marine Synechococcus Aggregation

    Science.gov (United States)

    Neuer, S.; Deng, W.; Cruz, B. N.; Monks, L.

    2016-02-01

    Cyanobacteria are considered to play an important role in the oceanic biological carbon pump, especially in oligotrophic regions. But as single cells are too small to sink, their carbon export has to be mediated by aggregate formation and possible consumption by zooplankton producing sinking fecal pellets. Here we report results on the aggregation of the ubiquitous marine pico-cyanobacterium Synechococcus as a model organism. We first investigated the mechanism behind such aggregation by studying the potential role of transparent exopolymeric particles (TEP) and the effects of nutrient (nitrogen or phosphorus) limitation on the TEP production and aggregate formation of these pico-cyanobacteria. We further studied the aggregation and subsequent settling in roller tanks and investigated the effects of the clays kaolinite and bentonite in a series of concentrations. Our results show that despite of the lowered growth rates, Synechococcus in nutrient limited cultures had larger cell-normalized TEP production, formed a greater volume of aggregates, and resulted in higher settling velocities compared to results from replete cultures. In addition, we found that despite their small size and lack of natural ballasting minerals, Synechococcus cells could still form aggregates and sink at measureable velocities in seawater. Clay minerals increased the number and reduced the size of aggregates, and their ballasting effects increased the sinking velocity and carbon export potential of aggregates. In comparison with the Synechococcus, we will also present results of the aggregation of the pico-cyanobacterium Prochlorococcus in roller tanks. These results contribute to our understanding in the physiology of marine Synechococcus as well as their role in the ecology and biogeochemistry in oligotrophic oceans.

  18. Blood, blood compounds and cell cultures irradiation in clinical radiotherapy equipment: studies on ideal volume and dose

    International Nuclear Information System (INIS)

    Fernandes, Marco Antonio R.; Pereira, Adelino Jose; Novaes, Paulo Eduardo R.S.

    1995-01-01

    The authors present the technic and equipment used by the Physical Radiologic Service of Radiation Therapy Department of A.C. Camargo Hospital to irradiate blood and blood compounds. The practical routine is illustrated. The results from others Institutions are presented, discussing about the homogeneity of dose of 2000 to 3500 c Gy to all target volume, sufficient to neutralize cells responsible by graft-versus-host disease from blood transfusions. (author). 6 refs., 2 figs., 1 tab

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

    Directory of Open Access Journals (Sweden)

    B. T. Dzumabaeva

    2011-01-01

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

  20. Effectiveness of structured teaching programme on knowledge regarding menstrual blood stem cells banking among nursing students

    OpenAIRE

    Neelam Hans; Sandeep Kaur

    2016-01-01

    Background: Menstrual blood banking enables women to store their menstrual blood under required conditions and preserve it for future. Stem cells present in the menstrual blood have the remarkable potential to develop into many different cell types in the body. The objective of the study was to assess the effectiveness of structured teaching programme on knowledge regarding menstrual blood stem cells banking among nursing students studying in selected nursing college of Amritsar, Punjab. M...

  1. Hematology, cytochemistry and ultrastructure of blood cells in fishing cat (Felis viverrina)

    OpenAIRE

    Prihirunkit, Kreangsak; Salakij, Chaleow; Apibal, Suntaree; Narkkong, Nual-Anong

    2007-01-01

    Hematological, cytochemical and ultrastructural features of blood cells in fishing cat (Felis viverrina) were evaluated using complete blood cell counts with routine and cytochemical blood stains, and scanning and transmission electron microscopy. No statistically significant difference was found in different genders of this animal. Unique features of blood cells in this animal were identified in hematological, cytochemical and ultrastructural studies. This study contributes to broaden hemato...

  2. Size, density and composition of cell-mineral aggregates formed during anoxygenic phototrophic Fe(II) oxidation: Impact on modern and ancient environments

    DEFF Research Database (Denmark)

    Posth, Nicole R.; Huelin, Sonia; Konhauser, Kurt O.

    2010-01-01

    Cell-Fe(III) mineral aggregates produced by anoxygenic Fe(II)-oxidizing photoautotrophic microorganisms (photoferrotrophs) may be influential in the modern Fe cycle and were likely an integral part of ancient biogeochemical cycles on early Earth. While studies have focused on the environmental...... conditions under which modern photoferrotrophs grow and the kinetics, physiology and mechanism of Fe(II) oxidation, no systematic analyses of the physico-chemical characteristics of those aggregates, such as shape, size, density and chemical composition, have as yet been conducted. Herein, experimental...... results show most aggregates are bulbous or ragged in shape, with an average particle size of 10-40??m, and densities that typically range between 2.0 and 2.4g/cm 3; the cell fraction of the aggregates increased and their density decreased with initial Fe(II) concentration. The mineralogy of the ferric...

  3. 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.

  4. 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.

  5. Anisotropic light scattering of individual sickle red blood cells.

    Science.gov (United States)

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

    2012-04-01

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

  6. 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 haematopoietic stem cells (HSC) in order to identify different practices and to explore whether recommendations can be made for harmonization....

  7. Aggregation of Organic Semiconductors and Its Influence on Carrier Transport and Solar Cell Performance

    KAUST Repository

    Hu, Hanlin

    2017-01-01

    Photovoltaic technology based on solution-processable organic solar cells (OSCs) provides a promising route towards a low-cost strategy to address the sharply increasing energy demands worldwide. However, up to date, the vast majority of solar cell

  8. 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.

  9. 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.

  10. Utilization of red blood cell transfusion in an obstetric setting.

    Science.gov (United States)

    Kamani, A A; McMorland, G H; Wadsworth, L D

    1988-11-01

    The transfusion experience for a 1-year period (September 1985 to August 1986) at a tertiary referral obstetric hospital was reviewed retrospectively. During the review period 7731 mothers were delivered and 6003 patients (83%) underwent type-and-screen procedures. A total of 1057 units of red blood cells were crossmatched, and 362 of these 1057 units were transfused to 100 parturient women so that the overall crossmatch/transfusion ratio was 2.9:1. Five percent of transfused patients received 1 unit; 52% of patients received 2 units, 19% received 3 units and 24% received greater than or equal to 4 units of packed red blood cells. Major indications for transfusion were uterine atony, 27%; retained placenta, 17%; trauma, 17%, placenta previa, 7%; and abruptio placentae, 5%. In 12% of patients transfusions were done because of anemia. This study shows the value of audit and confirms that the type-and-screen procedure is an effective way of reducing the crossmatch/transfusion ratio without compromising patient care, even in high-risk patients.

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. A Neural-Network-Based Approach to White Blood Cell Classification

    Directory of Open Access Journals (Sweden)

    Mu-Chun Su

    2014-01-01

    Full Text Available This paper presents a new white blood cell classification system for the recognition of five types of white blood cells. We propose a new segmentation algorithm for the segmentation of white blood cells from smear images. The core idea of the proposed segmentation algorithm is to find a discriminating region of white blood cells on the HSI color space. Pixels with color lying in the discriminating region described by an ellipsoidal region will be regarded as the nucleus and granule of cytoplasm of a white blood cell. Then, through a further morphological process, we can segment a white blood cell from a smear image. Three kinds of features (i.e., geometrical features, color features, and LDP-based texture features are extracted from the segmented cell. These features are fed into three different kinds of neural networks to recognize the types of the white blood cells. To test the effectiveness of the proposed white blood cell classification system, a total of 450 white blood cells images were used. The highest overall correct recognition rate could reach 99.11% correct. Simulation results showed that the proposed white blood cell classification system was very competitive to some existing systems.

  16. Graph Aggregation

    NARCIS (Netherlands)

    Endriss, U.; Grandi, U.

    Graph aggregation is the process of computing a single output graph that constitutes a good compromise between several input graphs, each provided by a different source. One needs to perform graph aggregation in a wide variety of situations, e.g., when applying a voting rule (graphs as preference

  17. Effect of red blood cells on platelet activation and thrombus formation in tortuous arterioles

    Directory of Open Access Journals (Sweden)

    Jennifer K. W. Chesnutt

    2013-12-01

    Full Text Available Thrombosis is a major contributor to cardiovascular disease, which can lead to myocardial infarction and stroke. Thrombosis may form in tortuous microvessels, which are often seen throughout the human body, but the microscale mechanisms and processes are not well understood. In straight vessels, the presence of red blood cells (RBCs is known to push platelets toward walls, which may affect platelet aggregation and thrombus formation. However in tortuous vessels, the effects of RBC interactions with platelets in thrombosis are largely unknown. Accordingly, the objective of this work was to determine the physical effects of RBCs, platelet size, and vessel tortuosity on platelet activation and thrombus formation in tortuous arterioles. A discrete element computational model was used to simulate the transport, collision, adhesion, aggregation, and shear-induced platelet activation of hundreds of individual platelets and RBCs in thrombus formation in tortuous arterioles. Results showed that high shear stress near the inner sides of curved arteriole walls activated platelets to initiate thrombosis. RBCs initially promoted platelet activation, but then collisions of RBCs with mural thrombi reduced the amount of mural thrombus and the size of emboli. In the absence of RBCs, mural thrombus mass was smaller in a highly tortuous arteriole compared to a less tortuous arteriole. In the presence of RBCs however, mural thrombus mass was larger in the highly tortuous arteriole compared to the less tortuous arteriole. As well, smaller platelet size yielded less mural thrombus mass and smaller emboli, either with or without RBCs. This study shed light on microscopic interactions of RBCs and platelets in tortuous microvessels, which have implications in various pathologies associated with thrombosis and bleeding.

  18. 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

  19. Hemoglobin redox reactions and red blood cell aging.

    Science.gov (United States)

    Rifkind, Joseph M; Nagababu, Enika

    2013-06-10

    The physiological mechanism(s) for recognition and removal of red blood cells (RBCs) from circulation after 120 days of its lifespan is not fully understood. Many of the processes thought to be associated with the removal of RBCs involve oxidative stress. We have focused on hemoglobin (Hb) redox reactions, which is the major source of RBC oxidative stress. The importance of Hb redox reactions have been shown to originate in large parts from the continuous slow autoxidation of Hb producing superoxide and its dramatic increase under hypoxic conditions. In addition, oxidative stress has been shown to be associated with redox reactions that originate from Hb reactions with nitrite and nitric oxide (NO) and the resultant formation of highly toxic peroxynitrite when NO reacts with superoxide released during Hb autoxidation. The interaction of Hb, particularly under hypoxic conditions with band 3 of the RBC membrane is critical for the generating the RBC membrane changes that trigger the removal of cells from circulation. These changes include exposure of antigenic sites, increased calcium leakage into the RBC, and the resultant leakage of potassium out of the RBC causing cell shrinkage and impaired deformability. The need to understand the oxidative damage to specific membrane proteins that result from redox reactions occurring when Hb is bound to the membrane. Proteomic studies that can pinpoint the specific proteins damaged under different conditions will help elucidate the cellular aging processes that result in cells being removed from circulation.

  20. Interaction of cationic carbosilane dendrimers and their complexes with siRNA with erythrocytes and red blood cell ghosts.

    Science.gov (United States)

    Wrobel, Dominika; Kolanowska, Katarzyna; Gajek, Arkadiusz; Gomez-Ramirez, Rafael; de la Mata, Javier; Pedziwiatr-Werbicka, Elżbieta; Klajnert, Barbara; Waczulikova, Iveta; Bryszewska, Maria

    2014-03-01

    We have investigated the interactions between cationic NN16 and BDBR0011 carbosilane dendrimers with red blood cells or their cell membranes. The carbosilane dendrimers used possess 16 cationic functional groups. Both the dendrimers are made of water-stable carbon-silicon bonds, but NN16 possesses some oxygen-silicon bonds that are unstable in water. The nucleic acid used in the experiments was targeted against GAG-1 gene from the human immunodeficiency virus, HIV-1. By binding to the outer leaflet of the membrane, carbosilane dendrimers decreased the fluidity of the hydrophilic part of the membrane but increased the fluidity of the hydrophobic interior. They induced hemolysis, but did not change the morphology of the cells. Increasing concentrations of dendrimers induced erythrocyte aggregation. Binding of short interfering ribonucleic acid (siRNA) to a dendrimer molecule decreased the availability of cationic groups and diminished their cytotoxicity. siRNA-dendrimer complexes changed neither the fluidity of biological membranes nor caused cell hemolysis. Addition of dendriplexes to red blood cell suspension induced echinocyte formation. Copyright © 2013 Elsevier B.V. All rights reserved.

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

    International Nuclear Information System (INIS)

    Benarroz, M.O.; Fonseca, A.S.; Rocha, G.S.; Frydman, J.N.G.; Rocha, V.C.; Pereira, M.O.

    2008-01-01

    Effects of Cinnamomum zeylanicum (cinnamon) on the labelling of blood constituents with technetium-99 m( 99m Tc) and on the morphology of red blood cells were studied. Blood samples from Wistar rats were incubated with cinnamon extract for 1hour or with 0.9% NaCl, as control. Labelling of blood constituents with 99m Tc was performed. Plasma (P) and blood cells (BC), soluble (SF-P and SF-BC) and insoluble (IF-P and IF-BC) fractions were separated. The radioactivity in each fraction was counted and the percentage of radioactivity incorporated (%ATI) was calculated. Blood smears were prepared, fixed, stained and the qualitative and quantitative morphological analysis of the red blood cells was evaluated. The data showed that the cinnamon extract decreased significantly (p 99m Tc, and although our results were obtained with animals, precaution is suggested in interpretations of nuclear medicine examinations involving the labelling of blood constituents in patients who are using cinnamon

  2. A Comparison of Bone Marrow and Cord Blood Mesenchymal Stem Cells for Cartilage Self-Assembly.

    Science.gov (United States)

    White, Jamie L; Walker, Naomi J; Hu, Jerry C; Borjesson, Dori L; Athanasiou, Kyriacos A

    2018-04-02

    Joint injury is a common cause of premature retirement for the human and equine athlete alike. Implantation of engineered cartilage offers the potential to increase the success rate of surgical intervention and hasten recovery times. Mesenchymal stem cells (MSCs) are a particularly attractive cell source for cartilage engineering. While bone marrow-derived MSCs (BM-MSCs) have been most extensively characterized for musculoskeletal tissue engineering, studies suggest that cord blood MSCs (CB-MSCs) may elicit a more robust chondrogenic phenotype. The objective of this study was to determine a superior equine MSC source for cartilage engineering. MSCs derived from bone marrow or cord blood were stimulated to undergo chondrogenesis through aggregate redifferentiation and used to generate cartilage through the self-assembling process. The resulting neocartilage produced from either BM-MSCs or CB-MSCs was compared by measuring mechanical, biochemical, and histological properties. We found that while BM constructs possessed higher tensile properties and collagen content, CB constructs had superior compressive properties comparable to that of native tissue and higher GAG content. Moreover, CB constructs had alkaline phosphatase activity, collagen type X, and collagen type II on par with native tissue suggesting a more hyaline cartilage-like phenotype. In conclusion, while both BM-MSCs and CB-MSCs were able to form neocartilage, CB-MSCs resulted in tissue more closely resembling native equine articular cartilage as determined by a quantitative functionality index. Therefore, CB-MSCs are deemed a superior source for the purpose of articular cartilage self-assembly.

  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. Aggregation Strength Tuning in Difluorobenzoxadiazole-Based Polymeric Semiconductors for High-Performance Thick-Film Polymer Solar Cells.

    Science.gov (United States)

    Chen, Peng; Shi, Shengbin; Wang, Hang; Qiu, Fanglong; Wang, Yuxi; Tang, Yumin; Feng, Jian-Rui; Guo, Han; Cheng, Xing; Guo, Xugang

    2018-06-27

    High-performance polymer solar cells (PSCs) with thick active layers are essential for large-scale production. Polymer semiconductors exhibiting a temperature-dependent aggregation property offer great advantages toward this purpose. In this study, three difluorobenzoxadiazole (ffBX)-based donor polymers, PffBX-T, PffBX-TT, and PffBX-DTT, were synthesized, which contain thiophene (T), thieno[3,2- b]thiophene (TT), and dithieno[3,2- b:2',3'- d]thiophene (DTT) as the π-spacers, respectively. Temperature-dependent absorption spectra reveal that the aggregation strength increases in the order of PffBX-T, PffBX-TT, and PffBX-DTT as the π-spacer becomes larger. PffBX-TT with the intermediate aggregation strength enables well-controlled disorder-order transition in the casting process of blend film, thus leading to the best film morphology and the highest performance in PSCs. Thick-film PSCs with an average power conversion efficiency (PCE) of 8.91% and the maximum value of 9.10% are achieved using PffBX-TT:PC 71 BM active layer with a thickness of 250 nm. The neat film of PffBX-TT also shows a high hole mobility of 1.09 cm 2 V -1 s -1 in organic thin-film transistors. When PffBX-DTT and PffBX-T are incorporated into PSCs utilizing PC 71 BM acceptor, the average PCE decreases to 6.54 and 1.33%, respectively. The performance drop mainly comes from reduced short-circuit current, as a result of nonoptimal blend film morphology caused by a less well-controlled film formation process. A similar trend was also observed in nonfullerene type thick-film PSCs using IT-4F as the electron acceptor. These results show the significance of polymer aggregation strength tuning toward optimal bulk heterojunction film morphology using ffBX-based polymer model system. The study demonstrates that adjusting π-spacer is an effective method, in combination with other important approaches such as alkyl chain optimization, to generate high-performance thick-film PSCs which are critical for

  5. Patient Blood Management in Europe: surveys on top indications for red blood cell use and Patient Blood Management organization and activities in seven European university hospitals.

    Science.gov (United States)

    Bruun, M T; Pendry, K; Georgsen, J; Manzini, P; Lorenzi, M; Wikman, A; Borg-Aquilina, D; van Pampus, E; van Kraaij, M; Fischer, D; Meybohm, P; Zacharowski, K; Geisen, C; Seifried, E; Liumbruno, G M; Folléa, G; Grant-Casey, J; Babra, P; Murphy, M F

    2016-11-01

    Patient Blood Management (PBM) in Europe is a working group of the European Blood Alliance with the initial objective to identify the starting position of the participating hospitals regarding PBM for benchmarking purposes, and to derive good practices in PBM from the experience and expertise in the participating teams with the further aim of implementing and strengthening these practices in the participating hospitals. We conducted two surveys in seven university hospitals in Europe: Survey on top indications for red blood cell use regarding usage of red blood cells during 1 week and Survey on PBM organization and activities. A total of 3320 units of red blood cells were transfused in 1 week at the seven hospitals. Overall, 61% of red cell units were transfused to medical patients and 36% to surgical patients, although there was much variation between hospitals. The organization and activities of PBM in the seven hospitals were variable, but there was a common focus on optimizing the treatment of bleeding patients, monitoring the use of blood components and treatment of preoperative anaemia. Although the seven hospitals provide a similar range of clinical services, there was variation in transfusion rates between them. Further, there was variable implementation of PBM activities and monitoring of transfusion practice. These findings provide a baseline to develop joint action plans to further implement and strengthen PBM across a number of hospitals in Europe. © 2016 International Society of Blood Transfusion.

  6. Influence of thermal annealing-induced molecular aggregation on film properties and photovoltaic performance of bulk heterojunction solar cells based on a squaraine dye

    Science.gov (United States)

    Zhang, Pengpeng; Ling, Zhitian; Chen, Guo; Wei, Bin

    2018-04-01

    Squaraine (SQ) dyes have been considered as efficient photoactive materials for organic solar cells. In this work, we purposely controlled the molecular aggregation of an SQ dye, 2,4-bis[4-(N,N-dibutylamino)-2-dihydroxyphenyl] SQ (DBSQ-(OH)2) in the DBSQ(OH)2:[6,6]-phenyl-C61-butyric acid methyl ester (PCBM) blend film by using the thermal annealing method, to study the influence of the molecular aggregation on film properties as well as the photovoltaic performance of DBSQ(OH)2:PCBM-based bulk heterojunction (BHJ) solar cells. Our results demonstrate that thermal annealing may change the aggregation behavior of DBSQ(OH)2 in the DBSQ(OH)2:PCBM film, and thus significantly influence the surface morphology, optical and electrical properties of the blend film, as well as the photovoltaic performance of DBSQ(OH)2:PCBM BHJ cells.

  7. 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.

  8. 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

  9. 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.

  10. Rydberg aggregates

    Science.gov (United States)

    Wüster, S.; Rost, J.-M.

    2018-02-01

    We review Rydberg aggregates, assemblies of a few Rydberg atoms exhibiting energy transport through collective eigenstates, considering isolated atoms or assemblies embedded within clouds of cold ground-state atoms. We classify Rydberg aggregates, and provide an overview of their possible applications as quantum simulators for phenomena from chemical or biological physics. Our main focus is on flexible Rydberg aggregates, in which atomic motion is an essential feature. In these, simultaneous control over Rydberg-Rydberg interactions, external trapping and electronic energies, allows Born-Oppenheimer surfaces for the motion of the entire aggregate to be tailored as desired. This is illustrated with theory proposals towards the demonstration of joint motion and excitation transport, conical intersections and non-adiabatic effects. Additional flexibility for quantum simulations is enabled by the use of dressed dipole-dipole interactions or the embedding of the aggregate in a cold gas or Bose-Einstein condensate environment. Finally we provide some guidance regarding the parameter regimes that are most suitable for the realization of either static or flexible Rydberg aggregates based on Li or Rb atoms. The current status of experimental progress towards enabling Rydberg aggregates is also reviewed.

  11. VALUE CHANGE DIAMETERRED BLOOD CELLS ATHLETES IN THE PHYSICAL LOAD

    Directory of Open Access Journals (Sweden)

    Lidiya Yurevna Rubtsova

    2017-05-01

    Full Text Available Background: to study the nature of distribution of erythrocytes on diameter in the circulating blood of skiers-racers during achievement of a threshold of anaerobic threshold (AТ. Materials and methods: Professional Skiers racers (young men and men, girls and women at the age of 17–37 years (n = 33 are еxamined in the conditions of physical activity on the stationary bicycle. The research is conducted according to the protocol approved by local committee on bioethics in case of Institute of Physiology of Komi Scientific Centre of the Ural Branch of the Russian Academy of Sciences. Samples of blood were taken from an elbow vein on an empty stomach, then from finger capillaries to, - on a threshold of anaerobic exchange, after execution of loading “to the full” and in 5 min restoration. On the stained blood smears measured diameter of 50 erythrocytes. Results processed statistically with use of an application program package of Windows (Basic, 2011. Results: At stage AT at 36% of athletes defined increase in average diameter of erythrocytes from 7,46 ± 0,06 to 7,68 ± 0,08 µm (р<0,05, without changes at 12% (7,45 ± 0,04 – 7,43 ± 0,05 µm and reduction of the size of cells at 52% from 7,51± 0,04 to 7,35 ± 0,05 µm (р<0,05. In the conditions of a maximum load (men have 337,1 ± 12,4 W and women have 246,7 ± 10,8 W and during the 5-minute recovery diameter of erythrocytes returned to the original value. Conclusion: Thus, the individual nature of change of average diameter of erythrocytes at athletes is shown during achievement of ANSPs and probably corresponds to selective elimination preferentially macro- or microcytes.

  12. Trends in US minority red blood cell unit donations.

    Science.gov (United States)

    Yazer, Mark H; Delaney, Meghan; Germain, Marc; Karafin, Matthew S; Sayers, Merlyn; Vassallo, Ralph; Ziman, Alyssa; Shaz, Beth

    2017-05-01

    To provide the appropriately diverse blood supply necessary to support alloimmunized and chronically transfused patients, minority donation recruitment programs have been implemented. This study investigated temporal changes in minority red blood cell (RBC) donation patterns in the United States. Data on donor race and ethnicity from 2006 through 2015, including the number of unique donors, collections, RBCs successfully donated, and average annual number of RBC donations per donor (donor fraction), were collected from eight US blood collectors. Minority donors were stratified into the following groups: Asian, black or African American, Hispanic or Latino, Native Indian or Alaska Native, Native Hawaiian or other Pacific Islander, white, multiracial/other, and no answer/not sure. Over the 10-year period, white donors annually constituted the majority of unique donors (range, 70.7%-73.9%), had the greatest proportion of collections (range, 76.1%-79.8%), and donated the greatest proportion of RBC units (range, 76.3%-80.2%). These donors also had the highest annual donor fraction (range, 1.82-1.91 units per donor). Black or African American donors annually constituted between 4.9 and 5.2% of all donors during the study period and donated between 4.0 and 4.3% of all RBC units. Linear regression analysis revealed decreasing numbers of donors, collections, and donated RBC units from white donors over time. Although the US population has diversified, and minority recruitment programs have been implemented, white donors constitute the majority of RBC donors and donations. Focused and effective efforts are needed to increase the proportion of minority donors. © 2017 AABB.

  13. Diagnosis and epidemiology of red blood cell enzyme disorders

    Directory of Open Access Journals (Sweden)

    Richard Van Wijk

    2013-03-01

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

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

    Science.gov (United States)

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

    2014-01-01

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

  15. 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.

  16. Abiotic factors in colony formation: effects of nutrition and light on extracellular polysaccharide production and cell aggregates of Microcystis aeruginosa

    Science.gov (United States)

    Yang, Zhen; Kong, Fanxiang

    2013-07-01

    Colony morphology is important for Microcystis to sustain a competitive advantage in eutrophic lakes. The mechanism of colony formation in Microcystis is currently unclear. Extracellular polysaccharide (EPS) has been reported to play an important role in cell aggregate formation of some phytoplankton. Microcystis aeruginosa was cultivated under varied abiotic conditions, including different nutrient, light, and temperature conditions, to investigate their effects on EPS production and morphological change. The results show that nutrient concentration and light intensity have great effects on EPS productionin M. aeruginosa. There was a considerable increase in EPS production after M. aeruginosa was cultivated in adjusted culture conditions similar to those present in the field (28.9 mg C/L, 1.98 mg N/L, 0.65 mg P/L, light intensity: 100 μmol/(m2 · s)). These results indicate that abiotic factors might be one of the triggers for colony formation in Microcystis.

  17. Neonatal nucleated red blood cells in G6PD deficiency.

    Science.gov (United States)

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

    2002-05-01

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

  18. Dense-body aggregates as plastic structures supporting tension in smooth muscle cells.

    Science.gov (United States)

    Zhang, Jie; Herrera, Ana M; Paré, Peter D; Seow, Chun Y

    2010-11-01

    The wall of hollow organs of vertebrates is a unique structure able to generate active tension and maintain a nearly constant passive stiffness over a large volume range. These properties are predominantly attributable to the smooth muscle cells that line the organ wall. Although smooth muscle is known to possess plasticity (i.e., the ability to adapt to large changes in cell length through structural remodeling of contractile apparatus and cytoskeleton), the detailed structural basis for the plasticity is largely unknown. Dense bodies, one of the most prominent structures in smooth muscle cells, have been regarded as the anchoring sites for actin filaments, similar to the Z-disks in striated muscle. Here, we show that the dense bodies and intermediate filaments formed cable-like structures inside airway smooth muscle cells and were able to adjust the cable length according to cell length and tension. Stretching the muscle cell bundle in the relaxed state caused the cables to straighten, indicating that these intracellular structures were connected to the extracellular matrix and could support passive tension. These plastic structures may be responsible for the ability of smooth muscle to maintain a nearly constant tensile stiffness over a large length range. The finding suggests that the structural plasticity of hollow organs may originate from the dense-body cables within the smooth muscle cells.

  19. 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...

  20. 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

  1. Mechanisms of Xenon Effect on Skin and Red Blood Cells

    DEFF Research Database (Denmark)

    Ponomarev, Alexander; Rodin, V.; Gurevich, Leonid

    2017-01-01

    The usage of Xenon (Xe) is known in anesthesia and biobanking areas. It is considered preservation effect of Xe is associated either with clathrate formation - solid gaseous structures or dissolution of Xe molecules in liquid phase without physical state modification (so-called hyperbarium) [1......]. This study is addressed to establish differences between hyberbarium or clathrate Xe actions as well as its applications on various bioobjects with anaerobic - red blood cells (RBCs) and aerobic (skin fragments) metabolism. Xe clathrates and hyperbarium storage were simulated under 277 K and 620-725 k...... to control (15.68 ± 1.11, CI95%). Skin fragments were harvested from rat tails and divided on hyberbarium, clathrate and dimetylsulfoxide cryopreserved as control group and stored for 7 days. Assessment was performed by point-score method including epidermal-dermal integrity various assays and engraftment...

  2. 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...

  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. Function, expression and localization of annexin A7 in platelets and red blood cells: Insights derived from an annexin A7 mutant mouse

    Directory of Open Access Journals (Sweden)

    Zamparelli Carlotta

    2003-08-01

    Full Text Available Abstract Background Annexin A7 is a Ca2+- and phospholipid-binding protein expressed as a 47 and 51 kDa isoform, which is thought to be involved in membrane fusion processes. Recently the 47 kDa isoform has been identified in erythrocytes where it was proposed to be a key component in the process of the Ca2+-dependent vesicle release, a process with which red blood cells might protect themselves against an attack by for example complement components. Results The role of annexin A7 in red blood cells was addressed in erythrocytes from anxA7-/- mice. Interestingly, the Ca2+-mediated vesiculation process was not impaired. Also, the membrane organization appeared not to be disturbed as assessed using gradient fractionation studies. Instead, lack of annexin A7 led to an altered cell shape and increased osmotic resistance of red blood cells. Annexin A7 was also identified in platelets. In these cells its loss led to a slightly slower aggregation velocity which seems to be compensated by an increased number of platelets. The results appear to rule out an important role of annexin A7 in membrane fusion processes occurring in red blood cells. Instead the protein might be involved in the organization of the membrane cytoskeleton. Red blood cells may represent an appropriate model to study the role of annexin A7 in cellular processes. Conclusion We have demonstrated the presence of both annexin A7 isoforms in red blood cells and the presence of the small isoform in platelets. In both cell types the loss of annexin A7 impairs cellular functions. The defects observed are however not compatible with a crucial role for annexin A7 in membrane fusion processes in these cell types.

  5. 78 FR 54257 - Advisory Council on Blood Stem Cell Transplantation; Request for Nominations for Voting Members

    Science.gov (United States)

    2013-09-03

    ...; Program priorities; research priorities; and the scope and design of the Stem Cell Therapeutic Outcomes... Council on Blood Stem Cell Transplantation; Request for Nominations for Voting Members AGENCY: Health... on the Advisory Council on Blood Stem Cell Transplantation (ACBSCT). The ACBSCT was established...

  6. Red blood cell and platelet genotyping: from current practice to future high-throughput donor typing

    NARCIS (Netherlands)

    de Haas, M.; van der Schoot, C. E.; Beiboer, S. H. W.; Feskens, M.; Cheroutre, G.; Maaskant-van Wijkb, P. A.

    2006-01-01

    The molecular basis of almost all red cell and platelet blood group antigens is known. This enables the prediction of red cell or platelet phenotypes based upon the genotypes. In many laboratories, blood group genotyping assays are routinely used in cases where patient red cells cannot be used for

  7. ENDOGENOUS PYROGEN RELEASE FROM RABBIT BLOOD CELLS INCUBATED IN VITRO WITH PARAINFLUENZA VIRUS.

    Science.gov (United States)

    ATKINS, E; CRONIN, M; ISACSON, P

    1964-12-11

    Rabbit blood cells incubated in vitro with purified parainfluenza-5 virus (DA strain) released a rapidly acting pyrogen. Spleen and lymph node cells were inactive. The pyrogen resembled in behavior a pyrogen extracted from granulocytic exudates. Similar cells in the blood are believed to be activated by virus in vivo to produce the circulating endogenous pyrogen that mediates virus-induced fever.

  8. False positive paediatric labelled white blood cell study

    International Nuclear Information System (INIS)

    Beveridge, N.; Bennett, E.; Thomas, P.

    2002-01-01

    Full text: An eight-month-old female presented for a technetium labelled white blood cell study (LWBC) to exclude an intra-abdominal abscess. Born premature, the child had surgery to repair a perforated bowel and had repeated presentations with diarrhoea, fevers, a tender right upper quadrant and a raised leucocyte count. Multiple imaging modalities failed to demonstrate recurrent bowel perforation, ischaemia or an intra-abdominal mass. A LWBC study was performed with whole body imaging at 1 and 5 hours post re-injection of the radiolabelled blood. No abnormal uptake was visualised in the abdomen but abnormal white cell accumulation was noted in the right hind foot and the length of the right lower leg. This activity appeared to lie along the course of the right tibia. Plain X-ray demonstrated no evidence of tibial osteomyelitis. Concern that the LWBC may be falsely negative in a patient on antibiotics, a gallium scan was immediately performed to re-examine the abdomen. The whole body gallium images demonstrated normal physiological uptake in the abdomen and no evidence of infection in the right leg. The patient had no clinical features to support right leg pathology. The abnormal LWBC localisation in the right lower leg/foot was therefore falsely positive. The most likely explanation is increased activation of the autologous LWBC by 'rough' handling during difficult venesection and re-injection through small veins and needles/cannulas. The slow flow through the veins draining the foot injection site would contribute to margination in these vessel walls. This is a potential cause for false positive LWBC studies- with significant implications for patient care. Copyright (2002) The Australian and New Zealand Society of Nuclear Medicine Inc

  9. Cost-effective and rapid blood analysis on a cell-phone.

    Science.gov (United States)

    Zhu, Hongying; Sencan, Ikbal; Wong, Justin; Dimitrov, Stoyan; Tseng, Derek; Nagashima, Keita; Ozcan, Aydogan

    2013-04-07

    We demonstrate a compact and cost-effective imaging cytometry platform installed on a cell-phone for the measurement of the density of red and white blood cells as well as hemoglobin concentration in human blood samples. Fluorescent and bright-field images of blood samples are captured using separate optical attachments to the cell-phone and are rapidly processed through a custom-developed smart application running on the phone for counting of blood cells and determining hemoglobin density. We evaluated the performance of this cell-phone based blood analysis platform using anonymous human blood samples and achieved comparable results to a standard bench-top hematology analyser. Test results can either be stored on the cell-phone memory or be transmitted to a central server, providing remote diagnosis opportunities even in field settings.

  10. [Allogenic hematopoietic stem cell transplantation with unrelated cord blood: report of three cases from the Chilean cord blood bank].

    Science.gov (United States)

    Barriga, Francisco; Wietstruck, Angélica; Rojas, Nicolás; Bertin, Pablo; Pizarro, Isabel; Carmona, Amanda; Guilof, Alejandro; Rojas, Iván; Oyarzún, Enrique

    2013-08-01

    Public cord blood banks are a source of hematopoietic stem cells for patients with hematological diseases who lack a family donor and need allogeneic transplantation. In June 2007 we started a cord blood bank with units donated in three maternity wards in Santiago, Chile. We report the first three transplants done with cord blood units form this bank. Cord blood units were obtained by intrauterine collection at delivery. They were depleted of plasma and red cells and frozen in liquid nitrogen. Tests for total nucleated cells, CD34 cell content, viral serology, bacterial cultures and HLA A, B and DRB1 were done. Six hundred cord blood units were stored by March 2012. Three patients received allogeneic transplant with cord blood from our bank, two with high risk lymphoblastic leukemia and one with severe congenital anemia. They received conditioning regimens according to their disease and usual supportive care for unrelated donor transplantation until full hematopoietic and immune reconstitution was achieved. The three patients had early engraftment of neutrophils and platelets. The child corrected his anemia and the leukemia patients remain in complete remission. The post-transplant course was complicated with Epstein Barr virus, cytomegalovirus and BK virus infection. Two patients are fully functional 24 and 33 months after transplant, the third is still receiving immunosuppression.

  11. [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.

  12. 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

  13. 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

  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. Serial alterations in digital hemodynamics and endothelin-1 immunoreactivity, platelet-neutrophil aggregation, and concentrations of nitric oxide, insulin, and glucose in blood obtained from horses following carbohydrate overload.

    Science.gov (United States)

    Eades, Susan C; Stokes, Ashley M; Johnson, Philip J; LeBlanc, Casey J; Ganjam, Venkataseshu K; Buff, Preston R; Moore, Rustin M

    2007-01-01

    To quantify changes in endothelium-derived factors and relate those changes to various aspects of digital hemodynamics during the prodromal stages of carbohydrate overload (CHO)-induced laminitis in horses. 20 adult horses without abnormalities of the digit. Digital and jugular venous blood samples were collected at 1-hour intervals (for assessment of endothelin-1 [ET-1] immunoreactivity and measurement of glucose, insulin, and nitric oxide [NO] concentrations) or 4-hour intervals (CBC and platelet-neutrophil aggregate assessment) for 8 hours or 16 hours after induction of CHO-associated laminitis in horses treated with an ET-1 antagonist. Effects of treatment, collection site, and time and the random effects of horse on each variable were analyzed by use of a repeated-measures model. Where treatment and collection site had no significant effect, data were combined. Compared with baseline values, CHO resulted in changes in several variables, including a significant increase from baseline in digital blood ET-like immunoreactivity at 11 hours; digital blood ET-like immunoreactivity was significantly greater than that in jugular venous blood at 8, 9, 11, and 12 hours. Digital and jugular venous blood concentrations of glucose increased from baseline significantly at 3, 4, and 5 hours; insulin concentration increased significantly at 5 hours; and the number of platelet-neutrophil aggregates increased significantly at 12 hours. In horses, concurrent increases in venous blood ET-1 immunoreactivity, insulin and glucose concentrations, and platelet-neutrophil aggregates support a role of endothelial dysfunction in the pathogenesis of CHO-induced laminitis.

  16. Effects of chronic morphine and morphine withdrawal on gene expression in rat peripheral blood mononuclear cells.

    OpenAIRE

    Desjardins , Stephane; Belkai , Emilie; Crete , Dominique; Cordonnier , Laurie; Scherrmann , Jean-Michel; Noble , Florence; Marie-Claire , Cynthia

    2008-01-01

    International audience; Chronic morphine treatment alters gene expression in brain structures. There are increasing evidences showing a correlation, in gene expression modulation, between blood cells and brain in psychological troubles. To test whether gene expression regulation in blood cells could be found in drug addiction, we investigated gene expression profiles in peripheral blood mononuclear (PBMC) cells of saline and morphine-treated rats. In rats chronically treated with morphine, th...

  17. Mimicking the Interfacial Dynamics of Flowing White Blood Cells

    Science.gov (United States)

    Santore, Maria

    2015-03-01

    The rolling of particles on surfaces, facilitated by hydrodynamic forces combined with localized surface interactions of the appropriate strengths, spatial arrangements, and ranges, is a technologically useful means of transporting and manipulating particles. One's intuition for the rolling of a marble or a car tire cannot be extrapolated down to microparticle length scales because the microparticle interactions are dominated by electrostatic, van der Waals, and hydrogen bonding interactions rather than a friction that depends on an imposed normal force. Indeed, our microparticle rolling systems are inspired by the rolling of white blood cells on the inner walls of venules as part of the innate immune response: Selectin molecules engage with their counterparts on the opposing surfaces to slow cell motion relative to that for freely flowing cells. In the resulting rolling signature, ligand-receptor binding and crack closing on the front of the cell are balanced with molecular dis-bonding and crack opening at the rear. The contact region is relatively static, allowing other interactions (for instance signaling) to occur for a finite duration. Thus, achieving particle rolling in synthetic systems is important because it facilitates particle-surface interactions in a continuous nonfouling fashion where the contact surface is continually renewed. In developing a synthetic model for this system, we employ polymers to modify flowing particles and /or planar collectors, producing heterogeneous interfaces which can support rolling or produce other motion signatures such as skipping, arrest, or free flow. We identify, in the synthetic system, combinations of variables that produce rolling and demonstrate how the distinction between rolling and arrest is not a simple matter of the adhesion strength between the particles and the collector. Rolling is a cooperative process and the coordination of binding in one location with dis-bonding in another requires appropriate length

  18. 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

  19. Matrix expansion and syncytial aggregation of syndecan-1+ cells underpin villous atrophy in coeliac disease.

    Directory of Open Access Journals (Sweden)

    Camilla Salvestrini

    Full Text Available We studied the expression of sulphated glycosaminoglycans (GAGs in coeliac disease (CD mucosa, as they are critical determinants of tissue volume, which increases in active disease. We also examined mucosal expression of IL-6, which stimulates excess GAG synthesis in disorders such as Grave's ophthalmopathy.We stained archival jejunal biopsies from 5 children with CD at diagnosis, on gluten-free diet and challenge for sulphated GAGs. We then examined duodenal biopsies from 9 children with CD compared to 9 histological normal controls, staining for sulphated GAGs, heparan sulphate proteoglycans (HSPG, short-chain HSPG (Δ-HSPG and the proteoglycan syndecan-1 (CD138, which is expressed on epithelium and plasma cells. We confirmed findings with a second monoclonal in another 12 coeliac children. We determined mucosal IL-6 expression by immunohistochemistry and PCR in 9 further cases and controls, and used quantitative real time PCR for other Th17 pathway cytokines in an additional 10 cases and controls.In CD, HSPG expression was lost in the epithelial compartment but contrastingly maintained within an expanded lamina propria. Within the upper lamina propria, clusters of syndecan-1(+ plasma cells formed extensive syncytial sheets, comprising adherent plasma cells, lysed cells with punctate cytoplasmic staining and shed syndecan ectodomains. A dense infiltrate of IL-6(+ mononuclear cells was detected in active coeliac disease, also localised to the upper lamina propria, with significantly increased mRNA expression of IL-6 and IL-17A but not IL-23 p19.Matrix expansion, through syndecan-1(+ cell recruitment and lamina propria GAG increase, underpins villous atrophy in coeliac disease. The syndecan-1(+ cell syncytia and excess GAG production recapitulate elements of the invertebrate encapsulation reaction, itself dependent on insect transglutaminase and glutaminated early response proteins. As in other matrix expansion disorders, IL-6 is upregulated and

  20. Matrix Expansion and Syncytial Aggregation of Syndecan-1+ Cells Underpin Villous Atrophy in Coeliac Disease

    Science.gov (United States)

    Salvestrini, Camilla; Lucas, Mark; Lionetti, Paolo; Torrente, Franco; James, Sean; Phillips, Alan D.; Murch, Simon H.

    2014-01-01

    Background We studied the expression of sulphated glycosaminoglycans (GAGs) in coeliac disease (CD) mucosa, as they are critical determinants of tissue volume, which increases in active disease. We also examined mucosal expression of IL-6, which stimulates excess GAG synthesis in disorders such as Grave's ophthalmopathy. Methods We stained archival jejunal biopsies from 5 children with CD at diagnosis, on gluten-free diet and challenge for sulphated GAGs. We then examined duodenal biopsies from 9 children with CD compared to 9 histological normal controls, staining for sulphated GAGs, heparan sulphate proteoglycans (HSPG), short-chain HSPG (Δ-HSPG) and the proteoglycan syndecan-1 (CD138), which is expressed on epithelium and plasma cells. We confirmed findings with a second monoclonal in another 12 coeliac children. We determined mucosal IL-6 expression by immunohistochemistry and PCR in 9 further cases and controls, and used quantitative real time PCR for other Th17 pathway cytokines in an additional 10 cases and controls. Results In CD, HSPG expression was lost in the epithelial compartment but contrastingly maintained within an expanded lamina propria. Within the upper lamina propria, clusters of syndecan-1+ plasma cells formed extensive syncytial sheets, comprising adherent plasma cells, lysed cells with punctate cytoplasmic staining and shed syndecan ectodomains. A dense infiltrate of IL-6+ mononuclear cells was detected in active coeliac disease, also localised to the upper lamina propria, with significantly increased mRNA expression of IL-6 and IL-17A but not IL-23 p19. Conclusions Matrix expansion, through syndecan-1+ cell recruitment and lamina propria GAG increase, underpins villous atrophy in coeliac disease. The syndecan-1+ cell syncytia and excess GAG production recapitulate elements of the invertebrate encapsulation reaction, itself dependent on insect transglutaminase and glutaminated early response proteins. As in other matrix expansion disorders

  1. 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 ...

  2. In vitro transdifferentiation of human peripheral blood mononuclear cells to photoreceptor-like cells

    Directory of Open Access Journals (Sweden)

    Yukari Komuta

    2016-06-01

    Full Text Available Direct reprogramming is a promising, simple and low-cost approach to generate target cells from somatic cells without using induced pluripotent stem cells. Recently, peripheral blood mononuclear cells (PBMCs have attracted considerable attention as a somatic cell source for reprogramming. As a cell source, PBMCs have an advantage over dermal fibroblasts with respect to the ease of collecting tissues. Based on our studies involving generation of photosensitive photoreceptor cells from human iris cells and human dermal fibroblasts by transduction of photoreceptor-related transcription factors via retrovirus vectors, we transduced these transcription factors into PBMCs via Sendai virus vectors. We found that retinal disease-related genes were efficiently detected in CRX-transduced cells, most of which are crucial to photoreceptor functions. In functional studies, a light-induced inward current was detected in some CRX-transduced cells. Moreover, by modification of the culture conditions including additional transduction of RAX1 and NEUROD1, we found a greater variety of retinal disease-related genes than that observed in CRX-transduced PBMCs. These data suggest that CRX acts as a master control gene for reprogramming PBMCs into photoreceptor-like cells and that our induced photoreceptor-like cells might contribute to individualized drug screening and disease modeling of inherited retinal degeneration.

  3. 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.

  4. The effects of red blood cell preparation method on in vitro markers of red blood cell aging and inflammatory response.

    Science.gov (United States)

    Radwanski, Katherine; Garraud, Olivier; Cognasse, Fabrice; Hamzeh-Cognasse, Hind; Payrat, Jean-Marc; Min, Kyungyoon

    2013-12-01

    Studies are currently under way examining whether the age of stored red blood cells (RBCs) affects clinical outcome in transfusion recipients. The effects of storage duration on the RBC storage lesion are well documented, while fewer studies are available regarding the effect of RBC production method. In this study, we compared in vitro RBC quality variables and markers of inflammatory response in apheresis and whole blood (WB)-derived RBCs, specifically those prepared after an overnight room temperature hold (RTH) of WB. SAGM RBCs, prepared from WB after overnight RTH (n = 10), were compared to SAGM RBCs prepared using an apheresis device (Alyx, n = 10). As a control, SAGM RBCs were also prepared within 2 hours of WB collection (2-hr WB, n = 10). All RBCs were stored at 4°C for 42 days with weekly assay of in vitro variables, cytokines and/or chemokines, and neutrophil activation after incubation with RBC supernatant. RTH WB