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

International Nuclear Information System (INIS)

Garratty, G.

1983-01-01

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

Engineering of red cells of Arabidopsis thaliana and comparative genome-wide gene expression analysis of red cells versus wild-type cells.

Science.gov (United States)

Shi, Ming-Zhu; Xie, De-Yu

2011-04-01

We report metabolic engineering of Arabidopsis red cells and genome-wide gene expression analysis associated with anthocyanin biosynthesis and other metabolic pathways between red cells and wild-type (WT) cells. Red cells of A. thaliana were engineered for the first time from the leaves of production of anthocyanin pigment 1-Dominant (pap1-D). These red cells produced seven anthocyanin molecules including a new one that was characterized by LC-MS analysis. Wild-type cells established as a control did not produce anthocyanins. A genome-wide microarray analysis revealed that nearly 66 and 65% of genes in the genome were expressed in the red cells and wild-type cells, respectively. In comparison with the WT cells, 3.2% of expressed genes in the red cells were differentially expressed. The expression levels of 14 genes involved in the biosynthetic pathway of anthocyanin were significantly higher in the red cells than in the WT cells. Microarray and RT-PCR analyses demonstrated that the TTG1-GL3/TT8-PAP1 complex regulated the biosynthesis of anthocyanins. Furthermore, most of the genes with significant differential expression levels in the red cells versus the WT cells were characterized with diverse biochemical functions, many of which were mapped to different metabolic pathways (e.g., ribosomal protein biosynthesis, photosynthesis, glycolysis, glyoxylate metabolism, and plant secondary metabolisms) or organelles (e.g., chloroplast). We suggest that the difference in gene expression profiles between the two cell lines likely results from cell types, the overexpression of PAP1, and the high metabolic flux toward anthocyanins.

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

Directory of Open Access Journals (Sweden)

F. Adams

2015-01-01

Full Text Available Red blood cells undergo a series of biochemical fluctuations during 35–42-day storage period at 1°C to 6°C. The sodium/potassium pump is immobilised causing a decrease in intracellular potassium with an increase in cytoplasmic sodium levels, glucose levels decline, and acidosis occurs as a result of low pH levels. The frailty of stored erythrocytes triggers the formation of haemoglobin-containing microparticles and the release of cell-free haemoglobin which may add to transfusion difficulties. Lipid peroxidation, oxidative stress to band 3 structures, and other morphological and structural molecular changes also occur leading to spheroechinocytes and osmotic fragility. These changes that transpire in the red cells during the storage period are referred to as “storage lesions.” It is well documented that gamma irradiation exacerbates storage lesions and the reports of increased potassium levels leading to adverse reactions observed in neonates and infants have been of particular concern. There are, however, remarkably few systematic studies comparing the in vitro storage lesions of irradiated and nonirradiated red cell concentrates and it has been suggested that the impact of storage lesions on leucocyte reduced red blood cell concentrate (RBCC is incomplete. The review examines storage lesions in red blood cells and their adverse effects in reference to blood transfusion.

The Red Rectangle: An Astronomical Example of Mach Bands?

Science.gov (United States)

Brecher, K.

2005-12-01

Recently, the Hubble Space Telescope (HST) produced spectacular images of the "Red Rectangle". This appears to be a binary star system undergoing recurrent mass loss episodes. The image-processed HST photographs display distinctive diagonal lightness enhancements. Some of the visual appearance undoubtedly arises from actual variations in the luminosity distribution of the light of the nebula itself, i.e., due to limb brightening. Psychophysical enhancement similar to the Vasarely or pyramid effect also seems to be involved in the visual impression conveyed by the HST images. This effect is related to Mach bands (as well as to the Chevreul and Craik-O'Brien-Cornsweet effects). The effect can be produced by stacking concentric squares (or other geometrical figures such as rectangles or hexagons) of linearly increasing or decreasing size and lightness, one on top of another. We have constructed controllable Flash applets of this effect as part of the NSF supported "Project LITE: Light Inquiry Through Experiments". They can be found in the vision section of the LITE web site at http://lite.bu.edu. Mach band effects have previously been seen in medical x-ray images. Here we report for the first time the possibility that such effects play a role in the interpretation of astronomical images. Specifically, we examine to what extent the visual impressions of the Red Rectangle and other extended astronomical objects are purely physical (photometric) in origin and to what degree they are enhanced by psychophysical processes. To help assess the relative physical and psychophysical contributions to the perceived lightness effects, we have made use of a center-surround (Difference of Gaussians) filter we developed for MatLab. We conclude that local (lateral inhibition) and longer range human visual perception effects probably do contribute to the lightness features seen in astronomical objects like the Red Rectangle. Project LITE is supported by NSF Grant # DUE-0125992.

Directly observed reversible shape changes and hemoglobin stratification during centrifugation of human and Amphiuma red blood cells.

Science.gov (United States)

Hoffman, Joseph F; Inoué, Shinya

2006-02-21

This paper describes changes that occur in human and Amphiuma red blood cells observed during centrifugation with a special microscope. Dilute suspensions of cells were layered, in a centrifuge chamber, above an osmotically matched dense solution, containing Nycodenz, Ficoll, or Percoll (Pharmacia) that formed a density gradient that allowed the cells to slowly settle to an equilibrium position. Biconcave human red blood cells moved downward at low forces with minimum wobble. The cells oriented vertically when the force field was increased and Hb sedimented as the lower part of each cell became bulged and assumed a "bag-like" shape. The upper centripetal portion of the cell became thinner and remained biconcave. These changes occurred rapidly and were completely reversible upon lowering the centrifugal force. Bag-shaped cells, upon touching red cells in rouleau, immediately reverted to biconcave disks as they flipped onto a stack. Amphiuma red cells displayed a different type of reversible stratification and deformation at high force fields. Here the cells became stretched, with the nucleus now moving centrifugally, the Hb moving centripetally, and the bottom of the cells becoming thinner and clear. Nevertheless, the distribution of the marginal bands at the cells' rim was unchanged. We conclude that centrifugation, per se, while changing a red cell's shape and the distribution of its intracellular constituents, does so in a completely reversible manner. Centrifugation of red cells harboring altered or missing structural elements could provide information on shape determinants that are still unexplained.

Snap-lock bags with red band: A study of manufacturing characteristics, thermal and chemical properties.

Science.gov (United States)

Sim, Yvonne Hui Ying; Koh, Alaric C W; Lim, Shing Min; Yew, Sok Yee

2015-10-01

Drug packaging is commonly submitted to the Forensic Chemistry and Physics Laboratory of the Health Sciences Authority, Singapore, for examination. The drugs seized are often packaged in plastic bags. These bags are examined for linkages to provide law enforcement with useful associations between the traffickers and drug abusers. The plastic bags submitted may include snap-lock bags, some with a red band located above the snap-lock closure and some without. Current techniques for examination involve looking at the physical characteristics (dimensions, thickness and polarising patterns) and manufacturing marks of these bags. In cases where manufacturing marks on the main body of the bags are poor or absent, the manufacturing characteristics present on the red band can be examined. A study involving approximately 1000 bags was conducted to better understand the variations in the manufacturing characteristics of the red band. This understanding is crucial in helping to determine associations/eliminations between bags. Two instrumental techniques, namely differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FT-IR) were explored to evaluate the effectiveness of examining the chemical composition to discriminate the bags. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

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

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.

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

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

Adjustment of Sentinel-2 Multi-Spectral Instrument (MSI) Red-Edge Band Reflectance to Nadir BRDF Adjusted Reflectance (NBAR) and Quantification of Red-Edge Band BRDF Effects

OpenAIRE

David P. Roy; Zhongbin Li; Hankui K. Zhang

2017-01-01

Optical wavelength satellite data have directional reflectance effects over non-Lambertian surfaces, described by the bidirectional reflectance distribution function (BRDF). The Sentinel-2 multi-spectral instrument (MSI) acquires data over a 20.6° field of view that have been shown to have non-negligible BRDF effects in the visible, near-infrared, and short wave infrared bands. MSI red-edge BRDF effects have not been investigated. In this study, they are quantified by an examination of 6.6 mi...

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

Science.gov (United States)

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

2010-09-01

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

Abnormal red cell structure and function in neuroacanthocytosis.

Directory of Open Access Journals (Sweden)

Judith C A Cluitmans

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

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

International Nuclear Information System (INIS)

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

1984-01-01

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

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.

Noncytotoxic orange and red/green derivatives of DsRed-Express2 for whole-cell labeling

Directory of Open Access Journals (Sweden)

Glick Benjamin S

2009-04-01

Full Text Available Abstract Background Whole-cell labeling is a common application of fluorescent proteins (FPs, but many red and orange FPs exhibit cytotoxicity that limits their use as whole-cell labels. Recently, a tetrameric red FP called DsRed-Express2 was engineered for enhanced solubility and was shown to be noncytotoxic in bacterial and mammalian cells. Our goal was to create derivatives of this protein with different spectral properties. Results Building on previous studies of DsRed mutants, we created two DsRed-Express2 derivatives: E2-Orange, an orange FP, and E2-Red/Green, a dual-color FP with both red and green emission. We show that these new FPs retain the low cytotoxicity of DsRed-Express2. In addition, we show that these new FPs are useful as second or third colors for flow cytometry and fluorescence microscopy. Conclusion E2-Orange and E2-Red/Green will facilitate the production of healthy, stably fluorescent cell lines and transgenic organisms for multi-color labeling studies.

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....

Present status of intermediate band solar cell research

International Nuclear Information System (INIS)

Cuadra, L.; Marti, A.; Luque, A.

2004-01-01

The intermediate band solar cell is a theoretical concept with the potential for exceeding the performance of conventional single-gap solar cells. This novel photovoltaic converter bases its superior theoretical efficiency over single-gap solar cells by enhancing its photogenerated current, via the two-step absorption of sub-band gap photons, without reducing its output voltage. This is achieved through a material with an electrically isolated and partially filled intermediate band located within a higher forbidden gap. This material is commonly named intermediate band material. This paper centres on summarising the present status of intermediate band solar cell research. A number of attempts, which aim to implement the intermediate band concept, are being followed: the direct engineering of the intermediate band material, its implementation by means of quantum dots and the highly porous material approach. Among other sub-band gap absorbing proposals, there is a renewed interest on the impurity photovoltaic effect, the quantum well solar cells and the particularly promising proposal for the use of up- and down-converters

In vivo studies of the long-term 51Cr red cell survival of serologically incompatible red cell units

International Nuclear Information System (INIS)

Baldwin, M.L.; Ness, P.M.; Barrasso, C.; Kickler, T.S.; Drew, H.; Tsan, M.F.; Shirey, R.S.

1985-01-01

The long-term survival of serologically incompatible red cell units was measured in five patients with antibodies to high-frequency antigens. Initially, the survival of 1 ml of 51 Cr-labeled incompatible red cells was measured over 1 hour. After demonstrating that the 1-hour survival times were successful (greater than 70%), each patient then received 5 ml of the same 51 Cr-labeled red cells followed by the transfusion of the remainder of the red cell unit. The long-term T 1/2Cr survival for each case was patient 1 (anti-McCa), 15 days; patient 2 (anti-JMH), 12 days; patient 3 (anti-Kna), 31 days; patient 4 (anti-McCa), 12 days; and patient 5 (anti-Hya), 14 days. Each antibody tested in an in vitro homologous macrophage assay showed less than 5 percent phagocytosis. Anti-JMH was the only antibody to react with IgG subclass antisera and was determined to be IgG4. The macrophage assay, IgG subclass testing, and short-term (1 hour, 1 ml) 51 Cr survival studies all indicated that the short-term survival was good. However, only the measurement of long-term survival with transfused units of serologically incompatible red cells was able to determine the actual survival, and clinical significance of the alloantibodies. Determining the actual long-term survival by the method described here can be of importance for patients requiring chronic red cell transfusion

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...

Human Red Cells With Paroxysmal Nocturnal Haemoglobinuria ...

African Journals Online (AJOL)

The purified cells were used as hosts for the culture of P.falciparum in vitro. Results show that GPI-linked molecules on the red cell surface are not required for the efficient entry of the parasites, and that the PNH red cells are competent to sustain the growth of P.falciparum. Nigerian Quarterly Journal of Hospital Medicine Vol ...

Red cell autoantibodies characterized by competitive inhibition of iodine 125 Rh alloantibody binding and by immunoprecipitation of membrane proteins

International Nuclear Information System (INIS)

Pierce, S.W.; Victoria, E.J.; Masouredis, S.P.

1990-01-01

The relationship between determinants recognized by warm-type immunoglobulin G red cell autoantibodies and the Rh antigens was characterized by autoantibody competitive inhibition of iodine 125 Rh alloantibody binding and autoantibody immunoprecipitation of iodine 125 red blood cell membrane proteins. The majority of blood donor autoantibody recognized epitopes that are closely related to Rh antigens as determined by competitive inhibition studies. Eighteen of 20 (90%) autoantibodies inhibited anti-Rh(c) binding, 15 inhibited anti-Rh(E), 5 inhibited anti-Rh(D), and only 2 failed to inhibit any of the three Rh alloantibodies tested. Autoantibodies that inhibited anti-Rh(D) also inhibited anti-Rh(c) and anti-Rh(E) and all those that inhibited anti-Rh(E) also inhibited anti-Rh(c). Autoantibodies that inhibited all three Rh alloantibodies immunoprecipitated 30 kd membrane polypeptides, as did two of the three autoantibodies that inhibited only anti-Rh(c) and anti-Rh(E). One autoantibody in this group and two autoantibodies that inhibited only anti-Rh(c), as well as an autoantibody that did not inhibit any of the Rh alloantibodies, immunoprecipitated only a single membrane polypeptide identified as band 3. The majority of normal donor red blood cell autoantibodies inhibited the binding of Rh alloantibodies, which indicates that they either bound to the Rh polypeptides or to epitopes on band 3 that were closely associated with the Rh complex

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.

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.

Photoluminescence study of Congo red molecules under high pressure

International Nuclear Information System (INIS)

Wang, Z.P.; Zhang, Z.M.; Ding, Z.J.

2007-01-01

Pressure-induced changes on fluorescence spectra of Congo red molecules were examined up to 8.7 GPa using a diamond anvil cell at room temperature. The spectra changes are demonstrated to be sensitive to the pressure and solvent conditions. At hydrostatic pressure and with a solvent used as a pressure transmitting medium the fluorescence spectra show increase of intensity with elevated pressure up to about 2.3 GPa and then drop at higher pressures. For Congo red crystal under quasi-hydrostatic condition without solvent the fluorescence intensity decreases monotonically and the lower energy band becomes dominant with the pressure increasing. The three vibronic bands show red shifts with increase of pressure

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

Regional estimation of savanna grass nitrogen using the red-edge band of the RapidEye sensor

CSIR Research Space (South Africa)

Ramoelo, Abel

2012-10-01

Full Text Available recent high resolution spaceborne multispectral sensor (i.e. RapidEye) in the Kruger National Park (KNP) and its surrounding areas, South Africa. The RapidEyesensor contains five spectral bands in the visible-to-near infrared (VNIR), including a red...

Red cell ferritin and iron stores in chronic granulocytic leukemia

International Nuclear Information System (INIS)

Cermak, J.; Neuwirth, J.; Voglova, J.; Brabec, V.; Chrobak, L.

1994-01-01

Basic red cell ferritin was investigated in 28 patients with different phases of chronic granulocytic leukemia (GCL). Red cell ferritin was significantly decreased in remission after busulphan treatment and significantly elevated in the blast crisis as compared to healthy controls. Bone marrow stainable iron was decreased or absent in 86% of patients in the initial phase at the time of diagnosis and in 92% of those in remission. Red cell ferritin correlated with serum ferritin, however, serum ferritin level remained above normal range during all phases of the disease. A negative correlation between red cell ferritin and hemoglobin (Hb) (r = -0.605, p < 0.001) suggested that red cell ferritin level reflected the rate of iron utilization for heme synthesis. Decrease red cell iron observed in the remission may be explained by regression of dyserythropoiesis and by restoration of normal Hb synthesis after busulphan treatment. A progressive dyserythropoiesis in the blast crisis may lead to an increased red cell ferritin level. (author)

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

Radiolabeled red blood cells: status, problems, and prospects

Energy Technology Data Exchange (ETDEWEB)

Srivastava, S.C.

1983-01-01

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

Radiolabeled red blood cells: status, problems, and prospects

International Nuclear Information System (INIS)

Srivastava, S.C.

1983-01-01

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

Optical band gap demarcation around 2.15 eV depending on preferred orientation growth in red HgI{sub 2} films

Energy Technology Data Exchange (ETDEWEB)

Tyagi, Pankaj, E-mail: pankajtyagicicdu@gmail.com

2017-04-01

Thermally evaporated stoichiometric films of red HgI{sub 2} show preferred orientation growth with either (102) or (002) orientation. The as grown films shows a change from one preferred orientation to another depending on their thickness, open-air heat-treatment and in-situ heat treatment of films. The in-situ heat-treatment of thermally evaporated stoichiometric films of red HgI{sub 2} with preferred growth of (102) orientation shows a gradual linear decrease in film thickness with in-situ heat-treatment temperature. On in-situ heat-treatment above 80 °C, it is found that HgI{sub 2} films become thinner than 900 nm, which are otherwise difficult to grow due to high vapor pressure of HgI{sub 2}. For these films the preferred orientation also changed from (102) to (002). The optical band gap (E{sub g}) also found to increase linearly with in-situ heat-treatment temperature. It is interesting to note that in-situ heat-treated films having (002) orientation had higher values of optical band gap than (102) orientation films. On combining these results with those of as grown and open-air heat-treated red HgI{sub 2} films reported in the literature, it is evident that there exists an optical band gap demarcation around 2.15 eV for red HgI{sub 2} thin films depending on their preferred orientation growth. Films with (102) orientation are found to have optical band gap less than 2.15 eV and those with (002) orientation are found to have optical band gap more than 2.15 eV. This is irrespective of the physical mean of obtaining the preferred orientation. The preferred orientation can be achieved by either physical means such as growing films with higher thickness, heat-treating them for short duration in open air or heat-treating them in-situ.

Efficient frequency downconversion at the single photon level from the red spectral range to the telecommunications C-band.

Science.gov (United States)

Zaske, Sebastian; Lenhard, Andreas; Becher, Christoph

2011-06-20

We report on single photon frequency downconversion from the red part of the spectrum (738 nm) to the telecommunications C-band. By mixing attenuated laser pulses with an average photon number per pulse telecommunications wavelengths.

Combined effects of blue light and supplemental far-red light and effects of increasing red light with constant far-red light on growth of kidney bean [Phaseolus vulgaris] under mixtures of narrow-band light sources

International Nuclear Information System (INIS)

Hanyu, H.; Shoji, K.

2000-01-01

Increasing blue light and decreasing R: FR with supplementary far-red light affect morphogenesis, dry matter production and dry matter partitioning to leaves, stems and roots. In this study, the combined effects of the two spectral treatments were examined in kidney bean (Phaseolus vulgaris L.) grown under the mixture of four different narrow-band light sources. In addition, because the leaf and stem growth are accelerated by increasing red light (600-700 nm) in proportion to far-red light (700-800 nm) while keeping R : FR constant, this study was conducted to determine whether red light or far-red light causes the acceleration of growth. Increasing blue light (400-500 nm) and decreasing R : FR only interacted on stem extension. The results illustrated with figures suggest that blue light amplifies or attenuates the acceleration of stem extension caused by decreasing R : FR. On the other hand, increasing red light with constant far-red light had no influence on leaf expansion or stem extension while R : FR increased. Because the acceleration of leaf and stem growth is caused by increasing either far-red light or both red and far-red light in our environmental conditions, the stimulative effects on leaves and stems seem to require increases in far-red light rather than red light

In vivo regeneration of red cell 2,3-diphosphoglycerate following transfusion of DPG-depleted AS-1, AS-3 and CPDA-1 red cells.

Science.gov (United States)

Heaton, A; Keegan, T; Holme, S

1989-01-01

Regeneration of 2,3-diphosphoglycerate (DPG) was determined following transfusion of DPG-depleted group O red cells into group A recipients. Blood from five donors was stored in the adenine-containing solutions CPDA-1, AS-1 or AS-3 for 35 d at 4 degrees C. Post-transfusion red cell DPG and ATP were measured in separated group O red cells over a 7 d period. The studies confirmed rapid in vivo DPG regeneration with greater than or equal to 50% of the maximum level being achieved within 7 h. An average of 95% of the recipients' pre-transfusion DPG level was achieved by 72 h and by 7 d mean (+/- SEM) DPG levels relative to recipient's pre-transfusion DPG averaged 84% (+/- 13%), 92% (+/- 17%) and 84% (+/- 21%) for CPDA-1, AS-1 and AS-3 red cells, respectively. Results were comparable to those previously reported for blood stored in ACD for 15-20 d (Valeri & Hirsch, 1969; Beutler & Wood, 1969). The immediate regeneration rate, V, closely approximated first order regeneration kinetics with AS-3 red cells exhibiting double the rate of CPDA-1 red cells (P less than 0.001). AS-1 red cells exhibited an intermediate rate of regeneration which was not significantly different compared to either CPDA-1 or AS-3 (P greater than 0.05). V exhibited a significant (P less than 0.05) positive correlation with ATP levels 5-7 h post-infusion. ATP regeneration of the infused cells was rapid with a mean increase of 1.2 mumol/g Hb above post-storage levels being achieved 1 h following transfusion.

Evidence that cell surface charge reduction modifes capillary red cell velocity-flux relationships in hamster cremaster muscle

NARCIS (Netherlands)

Vink, H.; Wieringa, P. A.; Spaan, J. A.

1995-01-01

1. From capillary red cell velocity (V)-flux (F) relationships of hamster cremaster muscle a yield velocity (VF = 0) can be derived at which red cell flux is zero. Red cell velocity becomes intermittent and/or red blood cells come to a complete standstill for velocities close to this yield velocity,

21 CFR 864.8540 - Red cell lysing reagent.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Red cell lysing reagent. 864.8540 Section 864.8540 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Reagents § 864.8540 Red cell lysing reagent...

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

International Nuclear Information System (INIS)

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

1991-01-01

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

The restoration in vivo of 2,3-diphosphoglycerate (2,3-DPG) in stored red cells, after transfusion. The levels of red cells 2,3-DPG.

Science.gov (United States)

Stan, Ana; Zsigmond, Eva

2009-01-01

Since the main reason for transfusing preserved red cells is to increase the oxygen carrying capacity of the recipient, the circulating preserved red cells should have at the time of transfusion normal oxygen uptake and normal oxyhemoglobin dissociation characteristics. We evaluated the effectiveness of transfused red cells, through periodical determination of erythrocyte components, during 72 hours after transfusions of large quantities (3,000 mL) of blood. Three patients with massive hemorrhages, two after amputation and one after nephrectomy were given each 3,000 mL preserved blood (in ACD, 10 days, at 4 degrees C). Red cell 2,3-DPG and serum inorganic phosphorus were determined prior to transfusion and after, periodically, for three days. Red cell 2,3-DPG was determined by Krimsky's method and inorganic phosphorus by Kuttner and Lichtenstein's method. The in vivo restoration of 2,3-DPG--of transfused red cells is shown as a percentage of recipient's final 2,3-DPG level, and was calculated in each of the three patients. The level of erythrocyte 2,3-DPG was greater than 60% of the final level within 24 hours, after the end of transfusion. The in vivo rates of restoration of 2,3-DPG in transfused red cells for periods of 0-6, 6-24, 24-48 and 48-72 hours are 0.251, 0.238, 0.133, 0.120 mM/L cells/hour. The therapeutic significance of the increased oxygen affinity of stored blood becomes very important in clinical conditions, when large volumes of red cells are urgently needed. After massive transfusions, the restoration of 2,3-DPG in red cells produces a decrease of serum inorganic phosphorus through its consumption. The stored blood with low values of erythrocyte 2,3-DPG can be used without hesitation when correcting a chronic anemia for instance, but in acute situation, when the organism needs restoration of the oxygen releasing capacity within minutes, the resynthesis is obviously insufficient. In such situations, fresh blood or blood with a near normal 2,3-DPG

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.

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

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

Science.gov (United States)

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

2012-12-20

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

Modeling cell elongation during germ band retraction: cell autonomy versus applied anisotropic stress

International Nuclear Information System (INIS)

Lynch, Holley E; Shane Hutson, M; Veldhuis, Jim; Wayne Brodland, G

2014-01-01

The morphogenetic process of germ band retraction in Drosophila embryos involves coordinated movements of two epithelial tissues—germ band and amnioserosa. The germ band shortens along its rostral–caudal or head-to-tail axis, widens along its perpendicular dorsal-ventral axis, and uncurls from an initial ‘U’ shape. The amnioserosa mechanically assists this process by pulling on the crook of the U-shaped germ band. The amnioserosa may also provide biochemical signals that drive germ band cells to change shape in a mechanically autonomous fashion. Here, we use a finite-element model to investigate how these two contributions reshape the germ band. We do so by modeling the response to laser-induced wounds in each of the germ band’s spatially distinct segments (T1–T3, A1–A9) during the middle of retraction when segments T1–A3 form the ventral arm of the ‘U’, A4–A7 form its crook, and A8–A9 complete the dorsal arm. We explore these responses under a range of externally applied stresses and internal anisotropy of cell edge tensions—akin to a planar cell polarity that can drive elongation of cells in a direction parallel to the minimum edge tension—and identify regions of parameter space (edge-tension anisotropy versus stress anisotropy) that best match previous experiments for each germ band segment. All but three germ band segments are best fit when the applied stress anisotropy and the edge-tension anisotropy work against one another—i.e., when the isolated effects would elongate cells in perpendicular directions. Segments in the crook of the germ band (A4–A7) have cells that elongate in the direction of maximum external stress, i.e., external stress anisotropy is dominant. In most other segments, the dominant factor is internal edge-tension anisotropy. These results are consistent with models in which the amnioserosa pulls on the crook of the germ band to mechanically assist retraction. In addition, they suggest a mechanical cue for

Comparing Broad-Band and Red Edge-Based Spectral Vegetation Indices to Estimate Nitrogen Concentration of Crops Using Casi Data

Science.gov (United States)

Wang, Yanjie; Liao, Qinhong; Yang, Guijun; Feng, Haikuan; Yang, Xiaodong; Yue, Jibo

2016-06-01

In recent decades, many spectral vegetation indices (SVIs) have been proposed to estimate the leaf nitrogen concentration (LNC) of crops. However, most of these indices were based on the field hyperspectral reflectance. To test whether they can be used in aerial remote platform effectively, in this work a comparison of the sensitivity between several broad-band and red edge-based SVIs to LNC is investigated over different crop types. By using data from experimental LNC values over 4 different crop types and image data acquired using the Compact Airborne Spectrographic Imager (CASI) sensor, the extensive dataset allowed us to evaluate broad-band and red edge-based SVIs. The result indicated that NDVI performed the best among the selected SVIs while red edge-based SVIs didn't show the potential for estimating the LNC based on the CASI data due to the spectral resolution. In order to search for the optimal SVIs, the band combination algorithm has been used in this work. The best linear correlation against the experimental LNC dataset was obtained by combining the 626.20nm and 569.00nm wavebands. These wavelengths correspond to the maximal chlorophyll absorption and reflection position region, respectively, and are known to be sensitive to the physiological status of the plant. Then this linear relationship was applied to the CASI image for generating an LNC map, which can guide farmers in the accurate application of their N fertilization strategies.

Red cell survival and sequestration in acute intermittent porphyria

International Nuclear Information System (INIS)

Nawalkha, P.L.; Soni, S.G.; Agrawal, V.K.; Misra, S.N.

1980-01-01

Life span and sequestration of red cells have been studied in twenty one proved cases of acute intermittent porphyria of different age and sex group from Bikaner District, Rajasthan State (India). Chromium-51 labelled red cells were used in the study and the excess count method of Bughe Jones and Szur was used to calculate the index of sequestration. The mean apparent half survival time of erythrocytes in the control subjects was 25.9 +- 2.9 (S.D.) days and the same in the prophyria patients was 27.0 +- 3.8 days. This shows that the life span of red cells is normal in both the patient and the control. Excess destruction of red blood cells was found to take place in either spleen or liver in the disease and no excess accumulation of erythrocytes occurred over spleen as compared to liver. (M.G.B.)

Red-luminescence band: A tool for the quality assessment of germanium and silicon nanocrystals

Science.gov (United States)

Fraj, I.; Favre, L.; David, T.; Abbarchi, M.; Liu, K.; Claude, J. B.; Ronda, A.; Naffouti, M.; Saidi, F.; Hassen, F.; Maaref, H.; Aqua, J. N.; Berbezier, I.

2017-10-01

We present the photoluminescence (PL) emission of Silicon and Germanium nanocrystals (NCs) of different sizes embedded in two different matrices. Formation of the NCs is achieved via solid-state dewetting during annealing in a molecular beam epitaxy ultra-high vacuum system of ultrathin amorphous Si and Ge layers deposited at room temperature on SiO2. During the dewetting process, the bi-dimensional amorphous layers transform into small pseudo-spherical islands whose mean size can be tuned directly with the deposited thickness. The nanocrystals are capped either ex situ by silicon dioxide or in situ by amorphous Silicon. The surface-state dependent emission (typically in the range 1.74 eV-1.79 eV) exhibited higher relative PL quantum yields compared to the emission originating from the band gap transition. This red-PL emission comes from the radiative transitions between a Si band and an interface level. It is mainly ascribed to the NCs and environment features deduced from morphological and structural analyses. Power dependent analysis of the photoluminescence intensity under continuous excitation reveals a conventional power law with an exponent close to 1, in agreement with the type II nature of the emission. We show that Ge-NCs exhibit much lower quantum efficiency than Si-NCs due to non-radiative interface states. Low quantum efficiency is also obtained when NCs have been exposed to air before capping, even if the exposure time is very short. Our results indicate that a reduction of the non-radiative surface states is a key strategy step in producing small NCs with increased PL emission for a variety of applications. The red-PL band is then an effective tool for the quality assessment of NCs based structures.

Erythrokinetics, ferrokinetics and red cell survival in sickle cell anaemia under subtropical climatic conditions

International Nuclear Information System (INIS)

Cardenas, R.

1975-01-01

Ferrokinetic parameters were evaluated with 59 Fe and red-cell survival with 51 Cr by classical techniques in a total of 17 patients with sickle-cell disease. The mean plasma 59 Fe half-disappearance time in these patients was 29.5 min as compared with a normal value of 92 min, and the t1/2 51 Cr 8.0 days as compared with a normal value of 26.0 days. The mean red-cell iron turnover rate was elevated to 9 times normal. The increased destruction of red cells appeared to take place predominantly, though not entirely, in the spleen. Eight of the 17 patients studied were identified as having intercurrent complications, but these did not significantly affect the results of the investigations. A group of 5 boys in whom the red-cell iron turnover rate was elevated to a lesser degree than in the other patients were subjected to more detailed studies of plasma 59 Fe clearance with particular reference to ineffective erythropoiesis. In these patients, the plasma 59 Fe clearance curves showed precocious humps characteristic of ineffective erythropoiesis. Detailed analysis of the results indicated ineffective erythropoiesis corresponding to 3.6, 16.0, 22.6, 32.0 and 50.0 % of the iron initially taken up by the bone marrow. It is concluded that while the anaemia in most patients with sickle-cell disease is mainly due to shortened survival of the circulating red cells, with increased destruction of red cells in the spleen, ineffective erythropoiesis may none the less be an important factor determining the actual degree of this anaemia

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.

Red Dot Basal Cell Carcinoma: An Unusual Variant of a Common Malignancy.

Science.gov (United States)

Loh, Tiffany Y; Cohen, Philip R

2016-05-01

Red dot basal cell carcinoma is a distinct but rare subtype of basal cell carcinoma (BCC). It presents as a red macule or papule; therefore, in most cases, it may easily be mistaken for a benign vascular lesion, such as a telangiectasia or angioma. A red dot BCC in an older woman is described. Clinical and histological differences between red dot BCCs and telangiectasias are described. A 72-year-old woman initially presented with a painless red macule on her nose. Biopsy of the lesion established the diagnosis of a red dot BCC. Pubmed was searched for the following terms: angioma, basal cell carcinoma, dermoscope, diascopy, red dot, non-melanoma skin cancer, telangiectasia, and vascular. The papers were reviewed for cases of red dot basal cell carcinoma. Clinical and histological characteristics of red dot basal cell carcinoma and telangiectasias were compared. Red dot BCC is an extremely rare variant of BCC that may be confused with benign vascular lesions. Although BCCs rarely metastasize and are associated with low mortality, they have the potential to become locally invasive and destructive if left untreated. Thus, a high index of suspicion for red dot BCC is necessary. J Drugs Dermatol. 2016;15(5):645-647.

Reflection coefficients of permeant molecules in human red cell suspensions.

Science.gov (United States)

Owen, J D; Eyring, E M

1975-08-01

The Staverman reflection coefficient, sigma for several permeant molecules was determined in human red cell suspensions with a Durrum stopped-flow spectrophotometer. This procedure was first used with dog, cat, and beef red cells and with human red cells. The stopped-flow technique used was similar to the rapid-flow method used by those who originally reported sigma measurements in human red cells for molecules which rapidly penetrate the red cell membrane. The sigma values we obtained agreed with those previously reported for most of the slow penetrants, except malonamide, but disagreed with all the sigma values previously reported for the rapid penetrants. We were unable to calculate an "equivalent pore radius" with our sigma data. The advantages of our equipment and our experimental procedure are discussed. Our sigma data suggest that sigma is indirectly proportional to the log of the nonelectrolyte permeability coefficient, omega. Since a similar trend has been previously shown for log omega and molar volume of the permeant molecules, a correlatioo was shown between sigma and molar volume suggesting the membrane acts as a sieve.

The absolute counting of red cell-derived microparticles with red cell bead by flow rate based assay.

Science.gov (United States)

Nantakomol, Duangdao; Imwong, Malika; Soontarawirat, Ingfar; Kotjanya, Duangporn; Khakhai, Chulalak; Ohashi, Jun; Nuchnoi, Pornlada

2009-05-01

Activation of red blood cell is associated with the formation of red cell-derived microparticles (RMPs). Analysis of circulating RMPs is becoming more refined and clinically useful. A quantitative Trucount tube method is the conventional method uses for quantitating RMPs. In this study, we validated a quantitative method called "flow rate based assay using red cell bead (FCB)" to measure circulating RMPs in the peripheral blood of healthy subjects. Citrated blood samples collected from 30 cases of healthy subjects were determined the RMPs count by using double labeling of annexin V-FITC and anti-glycophorin A-PE. The absolute RMPs numbers were measured by FCB, and the results were compared with the Trucount or with flow rate based calibration (FR). Statistical correlation and agreement were analyzed using linear regression and Bland-Altman analysis. There was no significant difference in the absolute number of RMPs quantitated by FCB when compared with those two reference methods including the Trucount tube and FR method. The absolute RMPs count obtained from FCB method was highly correlated with those obtained from Trucount tube (r(2) = 0.98, mean bias 4 cell/microl, limit of agreement [LOA] -20.3 to 28.3 cell/microl), and FR method (r(2) = 1, mean bias 10.3 cell/microl, and LOA -5.5 to 26.2 cell/microl). This study demonstrates that FCB is suitable and more affordable for RMPs quantitation in the clinical samples. This method is a low cost and interchangeable to latex bead-based method for generating the absolute counts in the resource-limited areas. (c) 2008 Clinical Cytometry Society.

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...

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 ...

[Establishment and identification of mouse lymphoma cell line EL4 expressing red fluorescent protein].

Science.gov (United States)

Li, Yan-Jie; Cao, Jiang; Chen, Chong; Wang, Dong-Yang; Zeng, Ling-Yu; Pan, Xiu-Ying; Xu, Kai-Lin

2010-02-01

This study was purposed to construct a lentiviral vector encoding red fluorescent protein (DsRed) and transfect DsRed into EL4 cells for establishing mouse leukemia/lymphoma model expressing DsRed. The bicistronic SIN lentiviral transfer plasmid containing the genes encoding neo and internal ribosomal entry site-red fluorescent protein (IRES-DsRed) was constructed. Human embryonic kidney 293FT cells were co-transfected with the three plasmids by liposome method. The viral particles were collected and used to transfect EL4 cells, then the cells were selected by G418. The results showed that the plasmid pXZ208-neo-IRES-DsRed was constructed successfully, and the viral titer reached to 10(6) U/ml. EL4 cells were transfected by the viral solution efficiently. The transfected EL4 cells expressing DsRed survived in the final concentration 600 microg/ml of G418. The expression of DsRed in the transfected EL4 cells was demonstrated by fluorescence microscopy and flow cytometry. In conclusion, the EL4/DsRed cell line was established successfully.

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...

Enzymes and membrane proteins of ADSOL-preserved red blood cells

Directory of Open Access Journals (Sweden)

Maria Sueli Soares Leonart

2000-03-01

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

Exploring the Potential of WorldView-2 Red-Edge Band-Based Vegetation Indices for Estimation of Mangrove Leaf Area Index with Machine Learning Algorithms

Directory of Open Access Journals (Sweden)

Yuanhui Zhu

2017-10-01

Full Text Available To accurately estimate leaf area index (LAI in mangrove areas, the selection of appropriate models and predictor variables is critical. However, there is a major challenge in quantifying and mapping LAI using multi-spectral sensors due to the saturation effects of traditional vegetation indices (VIs for mangrove forests. WorldView-2 (WV2 imagery has proven to be effective to estimate LAI of grasslands and forests, but the sensitivity of its vegetation indices (VIs has been uncertain for mangrove forests. Furthermore, the single model may exhibit certain randomness and instability in model calibration and estimation accuracy. Therefore, this study aims to explore the sensitivity of WV2 VIs for estimating mangrove LAI by comparing artificial neural network regression (ANNR, support vector regression (SVR and random forest regression (RFR. The results suggest that the RFR algorithm yields the best results (RMSE = 0.45, 14.55% of the average LAI, followed by ANNR (RMSE = 0.49, 16.04% of the average LAI, and then SVR (RMSE = 0.51, 16.56% of the average LAI algorithms using 5-fold cross validation (CV using all VIs. Quantification of the variable importance shows that the VIs derived from the red-edge band consistently remain the most important contributor to LAI estimation. When the red-edge band-derived VIs are removed from the models, estimation accuracies measured in relative RMSE (RMSEr decrease by 3.79%, 2.70% and 4.47% for ANNR, SVR and RFR models respectively. VIs derived from red-edge band also yield better accuracy compared with other traditional bands of WV2, such as near-infrared-1 and near-infrared-2 band. Furthermore, the estimated LAI values vary significantly across different mangrove species. The study demonstrates the utility of VIs of WV2 imagery and the selected machine-learning algorithms in developing LAI models in mangrove forests. The results indicate that the red-edge band of WV2 imagery can help alleviate the saturation

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 ...

Study on the Measurement of 51Cr-tagged Red Cell Survival: Reevaluation of its method and the effect of Blood loss on red cell survival with 51Cr

International Nuclear Information System (INIS)

Choi, Hak Yong; Koh, Chang Soon; Lee, Moon Ho

1970-01-01

Reappraisal measurement of apparent half survival time of red cell by 51 Cr method was made and effects of blood-letting over red cell survival were observed. The study was performed on 53 normal male subjects under three different experimental conditions. 1) Group 1: Mean 51 Cr red cell half survival by ACD wash method was 29.7 days. T 1 /2 of Ascorbic acid method was 29.0 days in group with 100 mg dose and 29.1 days in group with 50 mg dose respectively. There was no difference between these two methods in regards to red cell half survival. No difference were noted in amount of ascorbic acid administered. 2) Group 2: As daily amount of blood loss in increased the shortening of red cell half survival was noted. Rapid phase was seen when blood loss ranged 10 to 25 ml per day, while slow phase noted when more loss amounted 25 ml more daily. Thus, it was clear that there was more than an exponential relation between T 1 /2 and the amount of blood loss. 3) Group 3: T 1 /2 measured cpm per whole blood was within normal range and T 1 /2 measured by cpm per red mass showed shortening tendency when compared with the former in the group measured after blood loss (from 25 ml daily up to 100 ml daily in 10 days). In the group with rather constant blood loss of 100 ml daily for 10 consecutive days revealed the significant difference in two measurement (P 1 /2 in non-steady state. When red cell production is increased compared with red cell destruction, T 1 /2 measured by cpm per red cell mass shorter than that by cpm per whole blood. Shortening of T 1 /2 measured by cpm per whole blood is more prominent, if red destruction is enhanced and exceeds production. 5) It is clear that when expressing red cell destruction rate, T 1 /2 measured by cpm per whole blood is more adequate and production more consistent with cpm red cell mass. 6) T 1 /2 measured during blood-letting, when corrected by amount of blood loss, it remains normal. It is erroneous to use conventional equational

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.

Field collapse due to band-tail charge in amorphous silicon solar cells

Energy Technology Data Exchange (ETDEWEB)

Wang, Qi; Crandall, R.S. [National Renewable Energy Lab., Golden, CO (United States); Schiff, E.A. [Syracuse Univ., NY (United States)

1996-05-01

It is common for the fill factor to decrease with increasing illumination intensity in hydrogenated amorphous silicon solar cells. This is especially critical for thicker solar cells, because the decrease is more severe than in thinner cells. Usually, the fill factor under uniformly absorbed red light changes much more than under strongly absorbed blue light. The cause of this is usually assumed to arise from space charge trapped in deep defect states. The authors model this behavior of solar cells using the Analysis of Microelectronic and Photonic Structures (AMPS) simulation program. The simulation shows that the decrease in fill factor is caused by photogenerated space charge trapped in the band-tail states rather than in defects. This charge screens the applied field, reducing the internal field. Owing to its lower drift mobility, the space charge due to holes exceeds that due to electrons and is the main cause of the field screening. The space charge in midgap states is small compared with that in the tails and can be ignored under normal solar-cell operating conditions. Experimentally, the authors measured the photocapacitance as a means to probe the collapsed field. They also explored the light intensity dependence of photocapacitance and explain the decrease of FF with the increasing light intensity.

CHEMICAL ABUNDANCES IN FIELD RED GIANTS FROM HIGH-RESOLUTION H-BAND SPECTRA USING THE APOGEE SPECTRAL LINELIST

International Nuclear Information System (INIS)

Smith, Verne V.; Cunha, Katia; Shetrone, Matthew D.; Meszaros, Szabolcs; Allende Prieto, Carlos; Bizyaev, Dmitry; Garcìa Pèrez, Ana; Majewski, Steven R.; Schiavon, Ricardo; Holtzman, Jon; Johnson, Jennifer A.

2013-01-01

High-resolution H-band spectra of five bright field K, M, and MS giants, obtained from the archives of the Kitt Peak National Observatory Fourier transform spectrometer, are analyzed to determine chemical abundances of 16 elements. The abundances were derived via spectrum synthesis using the detailed linelist prepared for the Sloan Digital Sky Survey III Apache Point Galactic Evolution Experiment (APOGEE), which is a high-resolution near-infrared spectroscopic survey to derive detailed chemical abundance distributions and precise radial velocities for 100,000 red giants sampling all Galactic stellar populations. The red giant sample studied here was chosen to probe which chemical elements can be derived reliably from the H-band APOGEE spectral region. These red giants consist of two K-giants (α Boo and μ Leo), two M-giants (β And and δ Oph), and one thermally pulsing asymptotic giant branch (TP-AGB) star of spectral type MS (HD 199799). Measured chemical abundances include the cosmochemically important isotopes 12 C, 13 C, 14 N, and 16 O, along with Mg, Al, Si, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, and Cu. The K and M giants exhibit the abundance signature of the first dredge-up of CN-cycle material, while the TP-AGB star shows clear evidence of the addition of 12 C synthesized during 4 He-burning thermal pulses and subsequent third dredge-up. A comparison of the abundances derived here with published values for these stars reveals consistent results to ∼0.1 dex. The APOGEE spectral region and linelist is thus well suited for probing both Galactic chemical evolution, as well as internal nucleosynthesis and mixing in populations of red giants via high-resolution spectroscopy.

CHEMICAL ABUNDANCES IN FIELD RED GIANTS FROM HIGH-RESOLUTION H-BAND SPECTRA USING THE APOGEE SPECTRAL LINELIST

Energy Technology Data Exchange (ETDEWEB)

Smith, Verne V.; Cunha, Katia [National Optical Astronomy Observatories, Tucson, AZ 85719 (United States); Shetrone, Matthew D. [Department of Astronomy and McDonald Observatory, University of Texas, Austin, TX 78712 (United States); Meszaros, Szabolcs; Allende Prieto, Carlos [Instituto d' Astrofisica de Canarias, E-38205, La Laguna, Tenerife (Spain); Bizyaev, Dmitry [Apache Point Observatory, Sunspot, NM 88349 (United States); Garcia Perez, Ana; Majewski, Steven R. [Department of Astronomy, University of Virginia, Charlottesville, VA 22904 (United States); Schiavon, Ricardo [Astrophysics Research Institute, Liverpool John Moores University, Liverpool L3 5UX (United Kingdom); Holtzman, Jon [Department of Astronomy, New Mexico State University, Las Cruces, NM 88003 (United States); Johnson, Jennifer A., E-mail: vsmith@noao.edu [Department of Astronomy, Ohio State University, Columbus, OH 43210 (United States)

2013-03-01

High-resolution H-band spectra of five bright field K, M, and MS giants, obtained from the archives of the Kitt Peak National Observatory Fourier transform spectrometer, are analyzed to determine chemical abundances of 16 elements. The abundances were derived via spectrum synthesis using the detailed linelist prepared for the Sloan Digital Sky Survey III Apache Point Galactic Evolution Experiment (APOGEE), which is a high-resolution near-infrared spectroscopic survey to derive detailed chemical abundance distributions and precise radial velocities for 100,000 red giants sampling all Galactic stellar populations. The red giant sample studied here was chosen to probe which chemical elements can be derived reliably from the H-band APOGEE spectral region. These red giants consist of two K-giants ({alpha} Boo and {mu} Leo), two M-giants ({beta} And and {delta} Oph), and one thermally pulsing asymptotic giant branch (TP-AGB) star of spectral type MS (HD 199799). Measured chemical abundances include the cosmochemically important isotopes {sup 12}C, {sup 13}C, {sup 14}N, and {sup 16}O, along with Mg, Al, Si, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, and Cu. The K and M giants exhibit the abundance signature of the first dredge-up of CN-cycle material, while the TP-AGB star shows clear evidence of the addition of {sup 12}C synthesized during {sup 4}He-burning thermal pulses and subsequent third dredge-up. A comparison of the abundances derived here with published values for these stars reveals consistent results to {approx}0.1 dex. The APOGEE spectral region and linelist is thus well suited for probing both Galactic chemical evolution, as well as internal nucleosynthesis and mixing in populations of red giants via high-resolution spectroscopy.

Stability of eosin-5'-maleimide dye used in flow cytometric analysis for red cell membrane disorders.

Science.gov (United States)

Mehra, Simmi; Tyagi, Neetu; Dorwal, Pranav; Pande, Amit; Jain, Dharmendra; Sachdev, Ritesh; Raina, Vimarsh

2015-06-01

The eosin-5'-maleimide (EMA) binding test using flow cytometry is a common method to measure reduced mean channel fluorescence (MCF) of EMA-labeled red blood cells (RBCs) from patients with red cell membrane disorders. The basic principle of the EMA-RBC binding test involves the covalent binding of EMA to lysine-430 on the first extracellular loop of band 3 protein. In the present study, the MCF of EMA was analyzed for samples derived from 12 healthy volunteers (controls) to determine the stability (i.e., the percentage decrease in fluorescence) of EMA over a period of 1 year. Comparison of periodical MCF readings over time, that is, at 2-month intervals, showed that there were no significant changes in mean channel fluorescence for up to 6 months; however, there was a significant decrease in MCF at 8 months. For optimal dye utilization, EMA remained stable only for up to 6 months. Therefore, we recommend reconstitution of the dye every 6 months when implementing this test and storage at -80℃ in dark conditions.

Density increment and decreased survival of rat red blood cells induced by cadmium

International Nuclear Information System (INIS)

Kunimoto, M.; Miura, T.

1986-01-01

Male Wistar rats were injected with CdCl 2 subcutaneously to examine in vivo effects of Cd on density and survival of red blood cells. During the 7 days after administration of 1.0 mg Cd/kg, the following sequence of events occurred: (1) a progressive increase in the amount of more dense red blood cells concomitant with a decrease in that of light red blood cells from the first to the third day; (2) an increase in the spleen weight at the third day; (3) a decrease in the hematocrit value and an increase in the amount of light red blood cells at the fifth day; and (4) a recovery of the hematocrit value at the seventh day. Five days after administration, the hematocrit value decreased in a dose-dependent mode and the decrease was significant at the 1% level at 1.0 and 1.5 mg Cd/kg. A highly significant splenomegaly was also observed at 0.5 to 1.5 mg Cd/kg. In order to label red blood cells in vivo, [ 3 H] diisopropylfluorophosphate ([ 3 H]DFP) was injected into rats. At Day 11, Cd at either 0.5 or 1.0 mg/kg was administered to [ 3 H]DFP-prelabeled animals. Cd administration accelerated 3 H-labeled red cell clearance from the blood. Six days after Cd administration, the radioactivity of red blood cells was 76 and 68% of the control at 0.5 and 1.0 mg Cd/kg, respectively. In vitro treatment of rat red density and accelerated in vivo clearance of red blood cells from the recipient circulation. These results show that Cd at low dose can cause anemia by increasing red cell density and by accelerating red cell sequestration, presumably in the spleen

Near-infrared Spectroscopic Observations of Comet C/2013 R1 (Lovejoy) by WINERED: CN Red-system Band Emission

Energy Technology Data Exchange (ETDEWEB)

Shinnaka, Yoshiharu; Yasui, Chikako; Izumi, Natsuko [National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan); Kawakita, Hideyo; Kondo, Sohei; Ikeda, Yuji; Kobayashi, Naoto; Hamano, Satoshi; Sameshima, Hiroaki; Fukue, Kei; Matsunaga, Noriyuki; Otsubo, Shogo; Takenaka, Keiichi; Watase, Ayaka; Kawanishi, Takafumi; Nakanishi, Kenshi; Nakaoka, Tetsuya [Laboratory of Infrared High-resolution Spectroscopy, Koyama Astronomical Observatory, Kyoto Sangyo University, Motoyama, Kamigamo, Kita-ku, Kyoto 603-8555 (Japan); Mizumoto, Misaki, E-mail: yoshiharu.shinnaka@nao.ac.jp, E-mail: kawakthd@cc.kyoto-su.ac.jp [Department of Astronomy, School of Science, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033 (Japan)

2017-08-01

Although high-resolution spectra of the CN red-system band are considered useful in cometary sciences, e.g., in the study of isotopic ratios of carbon and nitrogen in cometary volatiles, there have been few reports to date due to the lack of high-resolution ( R  ≡  λ /Δ λ  > 20,000) spectrographs in the near-infrared region around ∼1 μ m. Here, we present the high-resolution emission spectrum of the CN red-system band in comet C/2013 R1 (Lovejoy), acquired by the near-infrared high-resolution spectrograph WINERED mounted on the 1.3 m Araki telescope at the Koyama Astronomical Observatory, Kyoto, Japan. We applied our fluorescence excitation models for CN, based on modern spectroscopic studies, to the observed spectrum of comet C/2013 R1 (Lovejoy) to search for CN isotopologues ({sup 13}C{sup 14}N and {sup 12}C{sup 15}N). We used a CN fluorescence excitation model involving both a “pure” fluorescence excitation model for the outer coma and a “fully collisional” fluorescence excitation model for the inner coma region. Our emission model could reproduce the observed {sup 12}C{sup 14}N red-system band of comet C/2013 R1 (Lovejoy). The derived mixing ratio between the two excitation models was 0.94(+0.02/−0.03):0.06(+0.03/−0.02), corresponding to the radius of the collision-dominant region of ∼800–1600 km from the nucleus. No isotopologues were detected. The observed spectrum is consistent, within error, with previous estimates in comets of {sup 12}C/{sup 13}C (∼90) and {sup 14}N/{sup 15}N (∼150).

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

Science.gov (United States)

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

2013-09-01

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

Red Dot Basal Cell Carcinoma: Report of Cases and Review of This Unique Presentation of Basal Cell Carcinoma.

Science.gov (United States)

Cohen, Philip R

2017-03-22

Red dot basal cell carcinoma is a unique variant of basal cell carcinoma. Including the three patients described in this report, red dot basal cell carcinoma has only been described in seven individuals. This paper describes the features of two males and one female with red dot basal cell carcinoma and reviews the characteristics of other patients with this clinical subtype of basal cell carcinoma. A 70-year-old male developed a pearly-colored papule with a red dot in the center on his nasal tip. A 71-year-old male developed a red dot surrounded by a flesh-colored papule on his left nostril. Lastly, a 74-year-old female developed a red dot within an area of erythema on her left mid back. Biopsy of the lesions all showed nodular and/or superficial basal cell carcinoma. Correlation of the clinical presentation and pathology established the diagnosis of red dot basal cell carcinoma. The tumors were treated by excision using the Mohs surgical technique. Pubmed was searched with the keyword: basal, cell, cancer, carcinoma, dot, red, and skin. The papers generated by the search and their references were reviewed. Red dot basal cell carcinoma has been described in three females and two males; the gender was not reported in two patients. The tumor was located on the nose (five patients), back (one patient) and thigh (one patient). Cancer presented as a solitary small red macule or papule; often, the carcinoma was surrounded by erythema or a flesh-colored papule. Although basal cell carcinomas usually do not blanch after a glass microscope slide is pressed against them, the red dot basal cell carcinoma blanched after diascopy in two of the patients, resulting in a delay of diagnosis in one of these individuals. Dermoscopy may be a useful non-invasive modality for evaluating skin lesions when the diagnosis of red dot basal cell carcinoma is considered. Mohs surgery is the treatment of choice; in some of the patients, the ratio of the area of the postoperative wound to that

Immunospecific red cell binding of iodine 125-labeled immunoglobulin G erythrocyte autoantibodies

International Nuclear Information System (INIS)

Masouredis, S.P.; Branks, M.J.; Garratty, G.; Victoria, E.J.

1987-01-01

The primary interaction of autoantibodies with red cells has been studied by using labeled autoantibodies. Immunoglobulin G red cell autoantibodies obtained from IgG antiglobulin-positive normal blood donors were labeled with radioactive iodine and compared with alloanti-D with respect to their properties and binding behavior. Iodine 125 -labeled IgG autoantibody migrated as a single homogeneous peak with the same relative mobility as human IgG on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The isoelectric focusing pattern of labeled autoantibodies varied from donor to donor but was similar to that of alloanti-D, consisting of multiple IgG populations with isoelectric points in the neutral to alkaline range. 125 I-autoantibody bound to all human red cells of common Rh phenotypes. Evidence for immunospecific antibody binding of the labeled autoantibody was based on variation in equilibrium binding to nonhuman and human red cells of common and rare phenotypes, enhanced binding after red cell protease modification, antiglobulin reactivity of cell-bound IgG comparable to that of cell-bound anti-D, and saturation binding in autoantibody excess. Scatchard analysis of two 125 I-autoantibody preparations yielded site numbers of 41,500 and 53,300 with equilibrium constants of 3.7 and 2.1 X 10(8) L X mol-1. Dog, rabbit, rhesus monkey, and baboon red cells were antigen(s) negative by quantitative adsorption studies adsorbing less than 3% of the labeled autoantibody. Reduced ability of rare human D--red blood cells to adsorb the autoantibody and identification of donor autoantibodies that bind to Rh null red blood cells indicated that eluates contained multiple antibody populations of complex specificities in contrast to anti-D, which consists of a monospecific antibody population. Another difference is that less than 70% of the autoantibody IgG was adsorbed by maximum binding red blood cells as compared with greater than 85% for alloanti-D

Circulating red cell-derived microparticles in human malaria.

Science.gov (United States)

Nantakomol, Duangdao; Dondorp, Arjen M; Krudsood, Srivicha; Udomsangpetch, Rachanee; Pattanapanyasat, Kovit; Combes, Valery; Grau, Georges E; White, Nicholas J; Viriyavejakul, Parnpen; Day, Nicholas P J; Chotivanich, Kesinee

2011-03-01

In patients with falciparum malaria, plasma concentrations of cell-derived microparticles correlate with disease severity. Using flow cytometry, we quantified red blood cell-derived microparticles (RMPs) in patients with malaria and identified the source and the factors associated with production. RMP concentrations were increased in patients with Plasmodium falciparum (n = 29; median, 457 RMPs/μL [range, 13-4,342 RMPs/μL]), Plasmodium vivax (n = 5; median, 409 RMPs/μL [range, 281-503/μL]), and Plasmodium malariae (n = 2; median, 163 RMPs/μL [range, 127-200 RMPs/μL]) compared with those in healthy subjects (n = 11; median, 8 RMPs/μL [range, 3-166 RMPs/μL]; P = .01). RMP concentrations were highest in patients with severe falciparum malaria (P = .01). Parasitized red cells produced >10 times more RMPs than did unparasitized cells, but the overall majority of RMPs still derived from uninfected red blood cells (URBCs). In cultures, RMP production increased as the parasites matured. Hemin and parasite products induced RMP production in URBCs, which was inhibited by N-acetylcysteine, suggesting heme-mediated oxidative stress as a pathway for the generation of RMPs.

Red Cell Alloantibodies in Multiple Transfused Thalassaemia Patients.

Science.gov (United States)

Chaudhari, C N

2011-01-01

Thalassaemia major patients require lifelong transfusion support due to which they are prone for alloimmunization to foreign RBCs. Alloimmunization can be prevented by extended phenotype match blood transfusion. The study was conducted to know the extent of problem of alloimmunization and to find important red cell antibodies in thalassaemia patients. A cross-sectional study was conducted. A total of 32 thalassaemia patients were enrolled. The specimen was subjected to red cell alloantibody and autoantibody by column gel agglutination technique. R 1 (w) R 1 , R 2 R 2 , rr (papaine and non papain) and 11 cell panel reagent cells were used in screening and identification of alloantibodies respectively. Six (18.8 %) subjects were alloimmunized. All alloimmunized subjects were recipient of more than 20 units of transfusion. Total seven clinically significant alloantibodies were identified. Anti E and anti c were commonest antibodies in four (12.5%) patients. Red cell alloimmunization is an important risk in thalassaemia patient. 71.4% of alloantibodies were anti E and anti c type. Extended phenotype match blood transfusion for Rh-c and Rh-E antigens or level 2 antigen matching stringency needs to be explored in preventing alloimmunization in thalassaemia patients.

Role of red cells and plasma composition on blood sessile droplet evaporation

Science.gov (United States)

Lanotte, Luca; Laux, Didier; Charlot, Benoît; Abkarian, Manouk

2017-11-01

The morphology of dried blood droplets derives from the deposition of red cells, the main components of their solute phase. Up to now, evaporation-induced convective flows were supposed to be at the base of red cell distribution in blood samples. Here, we present a direct visualization by videomicroscopy of the internal dynamics in desiccating blood droplets, focusing on the role of cell concentration and plasma composition. We show that in diluted suspensions, the convection is promoted by the rich molecular composition of plasma, whereas it is replaced by an outward red blood cell displacement front at higher hematocrits. We also evaluate by ultrasounds the effect of red cell deposition on the temporal evolution of sample rigidity and adhesiveness.

Infra-Red Gas Analysers of Liquid Crystal Type for Environmental Monitoring

Directory of Open Access Journals (Sweden)

V. I. Nazarov

2004-01-01

Full Text Available The paper reveals an opportunity to use infra-red gas analysers on the basis of the developed dichroic liquid crystal cells for investigation of absorption bands of various gases in the near infrared spectral region.

The Red Blood Cell Membrane of Preterm Infants in the Early Neonatal Period

Directory of Open Access Journals (Sweden)

S. A. Perepelitsa

2014-01-01

Full Text Available Objective: to study the nanostructure of red blood cell membranes and erythrocyte index in preterm neonatal infants.Subjects and methods. The trial enrolled 47 neonatal infants, including 33 preterm infants who were included in a study group and 14 fullterm infants who formed a comparative group. The gestational age of the preterm infants was 33.3±1.9 weeks and the birth weight was 2065.4±304.8 g. Red blood cell counts, hemoglobin, and erythrocyte indices were estimat ed and the red blood cells were examined using an atomicforce microscope.Results. At birth, the preterm infants showed macrocytosis, intrauterine poikylocytosis, and the impaired nanostructure of red blood cell membranes. Intrauterine hypoxia affects the red blood cell membrane nanostructures: a phospholipid bilayer and a spectrin matrix, without damaging the membrane protein component. The detected changes are reversible and directed to maintaining the functional ability of red blood cells in a critical situation. At birth, gestational age, a baby's weight, hemoglobin, and blood cholesterol and standard bicarbonate levels influence the parameters of a red blood cell component. The early neonatal period was characterized by an active process on the red blood cell membranes and a change of morphological forms, suggesting the continuing postnatal rearrangement of erythropoiesis and a preterm infant's adaptation to new environmental conditions.

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.

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.

Effect of radiographic contrast media on the spectrin/band3-network of the membrane skeleton of erythrocytes.

Directory of Open Access Journals (Sweden)

Ralf-Peter Franke

Full Text Available The membrane of red blood cells consists of a phospholipid bilayer with embedded membrane proteins and is associated on the cytoplasmatic side with a network of proteins, the membrane skeleton. Band3 has an important role as centre of the functional complexes e.g. gas exchange complex and as element of attachment for the membrane skeleton maintaining membrane stability and flexibility. Up to now it is unclear if band3 is involved in the morphology change of red blood cells after contact with radiographic contrast media. The study revealed for the first time that Iopromide induced markedly more severe alterations of the membrane skeleton compared to Iodixanol whose effects were similar to erythrocytes suspended in autologous plasma. A remarkable clustering of band3 was found associated with an accumulation of band3 in spicules and also a sequestration of band3 to the extracellular space. This was evidently accompanied by a gross reduction of functional band3 complexes combined with a dissociation of spectrin from band3 leading to a loss of homogeneity of the spectrin network. It could be demonstrated for the first time that RCM not only induced echinocyte formation but also exocytosis of particles at least coated with band3.

Effect of Radiographic Contrast Media on the Spectrin/Band3-Network of the Membrane Skeleton of Erythrocytes

Science.gov (United States)

Franke, Ralf-Peter; Scharnweber, Tim; Fuhrmann, Rosemarie; Wenzel, Folker; Krüger, Anne; Mrowietz, Christof; Jung, Friedrich

2014-01-01

The membrane of red blood cells consists of a phospholipid bilayer with embedded membrane proteins and is associated on the cytoplasmatic side with a network of proteins, the membrane skeleton. Band3 has an important role as centre of the functional complexes e.g. gas exchange complex and as element of attachment for the membrane skeleton maintaining membrane stability and flexibility. Up to now it is unclear if band3 is involved in the morphology change of red blood cells after contact with radiographic contrast media. The study revealed for the first time that Iopromide induced markedly more severe alterations of the membrane skeleton compared to Iodixanol whose effects were similar to erythrocytes suspended in autologous plasma. A remarkable clustering of band3 was found associated with an accumulation of band3 in spicules and also a sequestration of band3 to the extracellular space. This was evidently accompanied by a gross reduction of functional band3 complexes combined with a dissociation of spectrin from band3 leading to a loss of homogeneity of the spectrin network. It could be demonstrated for the first time that RCM not only induced echinocyte formation but also exocytosis of particles at least coated with band3. PMID:24586837

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

Science.gov (United States)

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

2017-10-31

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

Thin-film intermediate band chalcopyrite solar cells

International Nuclear Information System (INIS)

Fuertes Marron, D.; Marti, A.; Luque, A.

2009-01-01

Chalcopyrite-based solar cells currently lead the efficiency tables of thin-film photovoltaic technologies. Further improvements are foreseen upon implementation of an intermediate band in the absorber layers. We present a theoretical analysis of the efficiency limit for this type of device as a function of factors such as the gap of the host, the relative position of the intermediate band with respect to the band edge and the level of light concentration used as illumination. We have also considered the impact of non-idealities on the performance of the device, particularly the effect of electronic losses related to non-radiative recombination

Structure and red shift of optical band gap in CdO–ZnO nanocomposite synthesized by the sol gel method

Energy Technology Data Exchange (ETDEWEB)

Mosquera, Edgar, E-mail: edemova@ing.uchile.cl [Laboratorio de Materiales a Nanoescala, Departamento de Ciencia de los Materiales, Facultad de Ciencias Físicas y Matemáticas, Universidad de Chile, Av. Tupper 2069, Santiago (Chile); Pozo, Ignacio del, E-mail: ignacio.dpf@gmail.com [Facultad de Ciencias Naturales, Matemáticas y del Medio Ambiente, Universidad Tecnológica Metropolitana, Av. José Pedro Alessandri 1242, Santiago (Chile); Morel, Mauricio, E-mail: mmorel@ing.uchile.cl [Laboratorio de Materiales a Nanoescala, Departamento de Ciencia de los Materiales, Facultad de Ciencias Físicas y Matemáticas, Universidad de Chile, Av. Tupper 2069, Santiago (Chile)

2013-10-15

The structure and the optical band gap of CdO–ZnO nanocomposites were studied. Characterization using X-ray diffraction (XRD), transmission electron microscopy (TEM) and diffuse reflectance spectroscopy (DRS) analysis confirms that CdO phase is present in the nanocomposites. TEM analysis confirms the formation of spheroidal nanoparticles and nanorods. The particle size was calculated from Debey–Sherrer′s formula and corroborated by TEM images. FTIR spectroscopy shows residual organic materials (aromatic/Olefinic carbon) from nanocomposites surface. CdO content was modified in the nanocomposites in function of polyvinylalcohol (PVA) added. The optical band gap is found to be red shift from 3.21 eV to 3.11 eV with the increase of CdO content. Photoluminescence (PL) measurements reveal the existence of defects in the synthesized CdO–ZnO nanocomposites. - Graphical abstract: Optical properties of ZnO, CdO and ZnO/CdO nanoparticles. Display Omitted - Highlights: • TEM analysis confirms the presence of spherical nanoparticles and nanorods. • The CdO phase is present in the nanocomposites. • The band gap of the CdO–ZnO nanocomposites is slightly red shift with CdO content. • PL emission of CdO–ZnO nanocomposite are associated to structural defects.

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

Techniques for measuring red cell, platelet, and WBC survival

International Nuclear Information System (INIS)

Mayer, K.; Freeman, J.E.

1986-01-01

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

Estimation of transfused red cell survival using an enzyme-linked antiglobulin test

International Nuclear Information System (INIS)

Kickler, T.S.; Smith, B.; Bell, W.; Drew, H.; Baldwin, M.; Ness, P.M.

1985-01-01

An enzyme-linked antiglobulin test (ELAT) method was developed to estimate survival of transfused red cells. This procedure is based on a principle analogous to that of the Ashby technique were antigenically distinct red cells are transfused and their survival studied. The authors compared the ELAT survival to the 51 Chromium method ( 51 Cr) in four patients. Three patients with hypoproliferative anemias showed T 1/2 by ELAT of 17.5, 18, and 17 days versus 18.5, 20, and 19 days by the 51 Cr method. A fourth patient with traumatic cardiac hemolysis had two studies performed. In this case, the ELAT showed a T 1/2 of 10 and 8.1 days while 51 Cr T 1/2 values were 11 and 10.5 days. The ELAT method for measuring red cell survival yielded data which agreed closely with the results of the 51 Cr method. Although 51 Cr is the accepted method for red cell survival, the ELAT method can be used to estimate transfused red cell survival

In vivo red cell destruction by anti-Lu6

International Nuclear Information System (INIS)

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

1990-01-01

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

Cardiac arrest due to hyperkalemia following irradiated packed red cells transfusion

Energy Technology Data Exchange (ETDEWEB)

Miyazawa, Kazuharu [Yamamoto-kumiai General Hospital, Noshiro, Akita (Japan); Ohta, Sukejuurou; Kojima, Yukiko; Mizunuma, Takahide; Nishikawa, Toshiaki

1998-11-01

We describe two cases of cardiac arrest due to hyperkalemia following transfusion of irradiated packed red cells. Case 1: Because sudden, rapid and massive hemorrage occurred in a 69-year-old male patient undergoing the left lobectomy of the liver, 8 units of irradiated packed red cells were rapidly transfused, the patient developed cardiac arrest. Serum kalium concentration after transfusion was 7.6 mEq/l. Case 2: A 7-month-old girl scheduled for closure of a ventricular septal defect, developed cardiac arrest due to hyperkalemia at the start of cardiopulmonary bypass. The extracorporeal circuit was primed with 6 units of irradiated packed red blood cells. Serum kalium concentration immediately after the start of cardiopulmonary bypass was 10.6 mEq/l. Analysis of kalium concentration in the pilot tubes of the same packs revealed 56-61 mEq/l. These case reports suggest that fresh irradiated packed red cells should be transfused during massive bleeding and for pediatric patients to prevent severe hyperkalemia. (author)

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

Energy Technology Data Exchange (ETDEWEB)

Bitensky, M.; Yoshida, Tatsuro

1996-04-01

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

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)

A comparison of methods of determining the 100 percent survival of preserved red cells

International Nuclear Information System (INIS)

Valeri, C.R.; Pivacek, L.E.; Ouellet, R.; Gray, A.

1984-01-01

Studies were done to compare three methods to determine the 100 percent survival value from which to estimate the 24-hour posttransfusion survival of preserved red cells. The following methods using small aliquots of 51 Cr-labeled autologous preserved red cells were evaluated: First, the 125 I-albumin method, which is an indirect measurement of the recipient's red cell volume derived from the plasma volume measured using 125 I-labeled albumin and the total body hematocrit. Second, the body surface area method (BSA) in which the recipient's red cell volume is derived from a body surface area nomogram. Third, an extrapolation method, which extrapolates to zero time the radioactivity associated with the red cells in the recipient's circulation from 10 to 20 or 15 to 30 minutes after transfusion. The three methods gave similar results in all studies in which less than 20 percent of the transfused red cells were nonviable (24-hour posttransfusion survival values of between 80-100%), but not when more than 20 percent of the red cells were nonviable. When 21 to 35 percent of the transfused red cells were nonviable (24-hour posttransfusion survivals of 65 to 79%), values with the 125 I-albumin method and the body surface area method were about 5 percent lower (p less than 0.001) than values with the extrapolation method. When greater than 35 percent of the red cells were nonviable (24-hour posttransfusion survival values of less than 65%), values with the 125 I-albumin method and the body surface area method were about 10 percent lower (p less than 0.001) than those obtained by the extrapolation method

Mechanism of Na,K-ATPase decline during sheep red cell maturation

International Nuclear Information System (INIS)

Grafova, E.; Blostein, R.

1987-01-01

Na,K-ATPase of immature and mature sheep red cells of both the high-K + and low-K + genotypes as well as cells of both types matured in vitro was detected using polyclonal antiserum to sheep kidney Na,K-ATPase. Following SDS-PAGE and immunoblotting, the major reactive component was the ∼ 100 kDa catalytic α subunit. A less prominent band migrating as a sharper, lower molecular weight (50 kDa) component than the kidney Na,K-ATPase β subunit is apparent in reticulocytes but not mature cells. Membranes from both genotypes showed identical immunologically reactive peptides, except for the lower intensity of the α subunit in the mature cells of the low- compared to high-K + sheep. Following culture of both types, moderate reduction in reactivity was apparent. Immunologically reactive α subunit as well as the 50 kDa species were detected in membranous material shed into the culture medium. This material was functionally inactive (lack of both [ 3 H] ouabain binding and Na + -dependent phosphorylation of Na,K-ATPase). The existence in reticulocytes of an intracellular pool of ouabain binding sites is evidenced in appearance of extra sites following rapid ATP depletion and also after addition of chloroquine. Taken together, these findings are consistent with a maturation-associated decrease of sodium pumps by a process of membrane recycling, processing and, to some extent, exocytosis

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.

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

The effect of xanthine oxidase and hypoxanthine on the permeability of red cells from patients with sickle cell anemia.

Science.gov (United States)

Al Balushi, Halima W M; Rees, David C; Brewin, John N; Hannemann, Anke; Gibson, John S

2018-03-01

Red cells from patients with sickle cell anemia (SCA) are under greater oxidative challenge than those from normal individuals. We postulated that oxidants generated by xanthine oxidase (XO) and hypoxanthine (HO) contribute to the pathogenesis of SCA through altering solute permeability. Sickling, activities of the main red cell dehydration pathways (P sickle , Gardos channel, and KCl cotransporter [KCC]), and cell volume were measured at 100, 30, and 0 mmHg O 2 , together with deoxygenation-induced nonelectrolyte hemolysis. Unexpectedly, XO/HO mixtures had mainly inhibitory effects on sickling, P sickle , and Gardos channel activities, while KCC activity and nonelectrolyte hemolysis were increased. Gardos channel activity was significantly elevated in red cells pharmacologically loaded with Ca 2+ using the ionophore A23187, consistent with an effect on the transport system per se as well as via Ca 2+ entry likely via the P sickle pathway. KCC activity is controlled by several pairs of conjugate protein kinases and phosphatases. Its activity, however, was also stimulated by XO/HO mixtures in red cells pretreated with N-ethylmaleimide (NEM), which is thought to prevent regulation via changes in protein phosphorylation, suggesting that the oxidants formed could also have direct effects on this transporter. In the presence of XO/HO, red cell volume was better maintained in deoxygenated red cells. Overall, the most notable effect of XO/HO mixtures was an increase in red cell fragility. These findings increase our understanding of the effects of oxidative challenge in SCA patients and are relevant to the behavior of red cells in vivo. © 2018 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society.

An electronic apparatus for early detection of changes in red cell ...

African Journals Online (AJOL)

1989-08-19

Aug 19, 1989 ... An electronic apparatus was developed for anaesthetists to use to detect changes in red cell concentration during sur- gery. The mechanism is based on the relationship between the red cell content and the electrical conductivity of blood. In a pilot study of 170 blood samples, a correlation coefficient.

Lifetime enhancement for multiphoton absorption in intermediate band solar cells

International Nuclear Information System (INIS)

Bezerra, Anibal T; Studart, Nelson

2017-01-01

A semiconductor structure consisting of two coupled quantum wells embedded into the intrinsic region of a p – i–n junction is proposed as an intermediate band solar cell with a photon ratchet state, which would lead to increasing the cell efficiency. The conduction subband of the right-hand side quantum well works as the intermediated band, whereas the excited conduction subband of the left-hand side quantum well operates as the ratchet state. The photoelectrons in the intermediate band are scattered through the thin wells barrier and accumulated into the ratchet subband. A rate equation model for describing the charge transport properties is presented. The efficiency of the current generation is analyzed by studying the occupation of the wells subbands, taking into account the charge dynamic behavior provided by the electrical contacts connected to the cell. The current generation efficiency depends essentially from the relations between the generation, recombination rates and the scattering rate to the ratchet state. The inclusion of the ratchet states led to both an increase and a decrease in the cell current depending on the transition rates. This suggests that the coupling between the intermediate band and the ratchet state is a key point in developing an efficient solar cell. (paper)

Lifetime enhancement for multiphoton absorption in intermediate band solar cells

Science.gov (United States)

Bezerra, Anibal T.; Studart, Nelson

2017-08-01

A semiconductor structure consisting of two coupled quantum wells embedded into the intrinsic region of a p-i-n junction is proposed as an intermediate band solar cell with a photon ratchet state, which would lead to increasing the cell efficiency. The conduction subband of the right-hand side quantum well works as the intermediated band, whereas the excited conduction subband of the left-hand side quantum well operates as the ratchet state. The photoelectrons in the intermediate band are scattered through the thin wells barrier and accumulated into the ratchet subband. A rate equation model for describing the charge transport properties is presented. The efficiency of the current generation is analyzed by studying the occupation of the wells subbands, taking into account the charge dynamic behavior provided by the electrical contacts connected to the cell. The current generation efficiency depends essentially from the relations between the generation, recombination rates and the scattering rate to the ratchet state. The inclusion of the ratchet states led to both an increase and a decrease in the cell current depending on the transition rates. This suggests that the coupling between the intermediate band and the ratchet state is a key point in developing an efficient solar cell.

Cost comparison of methods for preparation of neonatal red cell aliquots.

Science.gov (United States)

Lechuga, Diana; Thompson, Christina

2007-01-01

The purpose of this study was to compare the preparation costs of two common methods used for neonatal red blood cell transfusion aliquots. Three months of data from a Level 2 and Level 3 neonatal intensive care unit (NICU) were used to determine the comparative cost for red cell aliquot transfusions using an eight bag aliquot/transfer system or the syringe set system. Using leuko-poor red blood cell blood collected in Adsol and containing approximately 320 ml of red blood cells and supernatant solution, the average cost of neonatal transfusion aliquots was determined using the Charter Medical syringe set and the Charter Medical eight bag aliquot/transfer system. A total of 126 red blood cell transfusion aliquots were used over the three month period. The amount transfused with each aliquot ranged from 5.0 ml - 55.0 ml with an average of 24.0 ml per aliquot. The cost per aliquot using the eight aliquot/transfer set was calculated as $36.25 and the cost per aliquot using the syringe set cost was calculated as $30.71. Additional benefits observed with the syringe set included decreased blood waste. When comparing Charter Medical multiple aliquot bag sets and the Charter Medical syringe aliquot system to provide neonatal transfusions, the use of the syringe system decreased blood waste and proved more cost effective.

Novel semiconductor solar cell structures: The quantum dot intermediate band solar cell

International Nuclear Information System (INIS)

Marti, A.; Lopez, N.; Antolin, E.; Canovas, E.; Stanley, C.; Farmer, C.; Cuadra, L.; Luque, A.

2006-01-01

The Quantum Dot Intermediate Band Solar Cell (QD-IBSC) has been proposed for studying experimentally the operating principles of a generic class of photovoltaic devices, the intermediate band solar cells (IBSC). The performance of an IBSC is based on the properties of a semiconductor-like material which is characterised by the existence of an intermediate band (IB) located within what would otherwise be its conventional bandgap. The improvement in efficiency of the cell arises from its potential (i) to absorb below bandgap energy photons and thus produce additional photocurrent, and (ii) to inject this enhanced photocurrent without degrading its output photo-voltage. The implementation of the IBSC using quantum dots (QDs) takes advantage of the discrete nature of the carrier density of states in a 0-dimensional nano-structure, an essential property for realising the IB concept. In the QD-IBSC, the IB arises from the confined electron states in an array of quantum dots. This paper reviews the operation of the first prototype QD-IBSCs and discusses some of the lessons learnt from their characterisation

Novel semiconductor solar cell structures: The quantum dot intermediate band solar cell

Energy Technology Data Exchange (ETDEWEB)

Marti, A. [Instituto de Energia Solar-UPM, ETSIT de Madrid, Ciudad Universitaria sn, 28040 Madrid (Spain)]. E-mail: amarti@etsit.upm.es; Lopez, N. [Instituto de Energia Solar-UPM, ETSIT de Madrid, Ciudad Universitaria sn, 28040 Madrid (Spain); Antolin, E. [Instituto de Energia Solar-UPM, ETSIT de Madrid, Ciudad Universitaria sn, 28040 Madrid (Spain); Canovas, E. [Instituto de Energia Solar-UPM, ETSIT de Madrid, Ciudad Universitaria sn, 28040 Madrid (Spain); Stanley, C. [Department of Electronics and Electrical Engineering, University of Glasgow, Glasgow G12 8QQ (United Kingdom); Farmer, C. [Department of Electronics and Electrical Engineering, University of Glasgow, Glasgow G12 8QQ (United Kingdom); Cuadra, L. [Departamento de Teoria de la Senal y Comunicaciones- Escuela Politecnica Superior, Universidad de Alcala, Ctra. Madrid-Barcelona, km. 33600, 28805-Alcala de Henares (Madrid) (Spain); Luque, A. [Instituto de Energia Solar-UPM, ETSIT de Madrid, Ciudad Universitaria sn, 28040 Madrid (Spain)

2006-07-26

The Quantum Dot Intermediate Band Solar Cell (QD-IBSC) has been proposed for studying experimentally the operating principles of a generic class of photovoltaic devices, the intermediate band solar cells (IBSC). The performance of an IBSC is based on the properties of a semiconductor-like material which is characterised by the existence of an intermediate band (IB) located within what would otherwise be its conventional bandgap. The improvement in efficiency of the cell arises from its potential (i) to absorb below bandgap energy photons and thus produce additional photocurrent, and (ii) to inject this enhanced photocurrent without degrading its output photo-voltage. The implementation of the IBSC using quantum dots (QDs) takes advantage of the discrete nature of the carrier density of states in a 0-dimensional nano-structure, an essential property for realising the IB concept. In the QD-IBSC, the IB arises from the confined electron states in an array of quantum dots. This paper reviews the operation of the first prototype QD-IBSCs and discusses some of the lessons learnt from their characterisation.

Nanostructure of Red Blood Cell Membranes in Premature Neonates with Respiratory Distress Syndrome

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S. A. Perepelitsa

2013-01-01

Full Text Available Objective: to study the nanostructure of red blood cell membranes in premature babies with neonatal respiratory distress syndrome (NRDS, by applying atomic force microscopy. Subjects and methods. The investigation included 27 newborn infants, of them 13 premature babies with NRDS formed a study group. The mean gestational age was 33.1±2.3 weeks; their birth weight was 1800±299.3 g. A comparison group consisted of 14 full-term babies with favorable pregnancy and term labor. The mean gestational age of the babies was 39.4±0.5 weeks; their birth weight was 3131.7±588.8 g; the infants had a one minute Apgar score of 8±0.4. Their red blood cells were examined using an atomic force microscope. The objects to be examined were residual umbilical cord blood (RUCB from the premature infants; central venous blood after 7 hours of birth and neonatal venous blood taken on day 7 of life. Results. RUCB from full-term babies contained planocytes that were a major morphological type of red blood cells. In physiological pregnancy and acute fetal hypoxia, the morphological composition of red blood cells in premature neonates with NRDS was close to that in full-term babies. The planocytes are also a major morphological type of red blood cells in the premature infants; the frequency of their occurrence varies. Stomatocytes are typical of all the neonates in the NRDS group; their frequency levels vary greatly: from 8 to 65% of the total number of erythrocytes. The examination revealed that the premature infants of 31—36 weeks gestation were characterized by abnormal erythrocyte shapes that showed a high variability. At birth, the premature babies were found to have changes in the nanostructure of red blood cell membranes, which were influenced by intrauterine hypoxia. The first-order value reflecting flickering in the red blood cell membrane varies to the most extent. Conclusion. Atomic force microscopy showed that the greatest changes in the structure of red

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

Minimal RED Cell Pairs Markedly Improve Electrode Kinetics and Power Production in Microbial Reverse Electrodialysis Cells

KAUST Repository

Cusick, Roland D.

2013-12-17

Power production from microbial reverse electrodialysis cell (MRC) electrodes is substantially improved compared to microbial fuel cells (MFCs) by using ammonium bicarbonate (AmB) solutions in multiple RED cell pair stacks and the cathode chamber. Reducing the number of RED membranes pairs while maintaining enhanced electrode performance could help to reduce capital costs. We show here that using only a single RED cell pair (CP), created by operating the cathode in concentrated AmB, dramatically increased power production normalized to cathode area from both acetate (Acetate: from 0.9 to 3.1 W/m 2-cat) and wastewater (WW: 0.3 to 1.7 W/m2), by reducing solution and charge transfer resistances at the cathode. A second RED cell pair increased RED stack potential and reduced anode charge transfer resistance, further increasing power production (Acetate: 4.2 W/m2; WW: 1.9 W/m2). By maintaining near optimal electrode power production with fewer membranes, power densities normalized to total membrane area for the 1-CP (Acetate: 3.1 W/m2-mem; WW: 1.7 W/m2) and 2-CP (Acetate: 1.3 W/m2-mem; WW: 0.6 W/m2) reactors were much higher than previous MRCs (0.3-0.5 W/m2-mem with acetate). While operating at peak power, the rate of wastewater COD removal, normalized to reactor volume, was 30-50 times higher in 1-CP and 2-CP MRCs than that in a single chamber MFC. These findings show that even a single cell pair AmB RED stack can significantly enhance electrical power production and wastewater treatment. © 2013 American Chemical Society.

Minimal RED Cell Pairs Markedly Improve Electrode Kinetics and Power Production in Microbial Reverse Electrodialysis Cells

KAUST Repository

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

2013-01-01

Power production from microbial reverse electrodialysis cell (MRC) electrodes is substantially improved compared to microbial fuel cells (MFCs) by using ammonium bicarbonate (AmB) solutions in multiple RED cell pair stacks and the cathode chamber. Reducing the number of RED membranes pairs while maintaining enhanced electrode performance could help to reduce capital costs. We show here that using only a single RED cell pair (CP), created by operating the cathode in concentrated AmB, dramatically increased power production normalized to cathode area from both acetate (Acetate: from 0.9 to 3.1 W/m 2-cat) and wastewater (WW: 0.3 to 1.7 W/m2), by reducing solution and charge transfer resistances at the cathode. A second RED cell pair increased RED stack potential and reduced anode charge transfer resistance, further increasing power production (Acetate: 4.2 W/m2; WW: 1.9 W/m2). By maintaining near optimal electrode power production with fewer membranes, power densities normalized to total membrane area for the 1-CP (Acetate: 3.1 W/m2-mem; WW: 1.7 W/m2) and 2-CP (Acetate: 1.3 W/m2-mem; WW: 0.6 W/m2) reactors were much higher than previous MRCs (0.3-0.5 W/m2-mem with acetate). While operating at peak power, the rate of wastewater COD removal, normalized to reactor volume, was 30-50 times higher in 1-CP and 2-CP MRCs than that in a single chamber MFC. These findings show that even a single cell pair AmB RED stack can significantly enhance electrical power production and wastewater treatment. © 2013 American Chemical Society.

An electronic apparatus for early detection of changes in red cell ...

African Journals Online (AJOL)

An electronic apparatus was developed for anaesthetists to use to detect changes in red cell concentration during surgery. The mechanism is based on the relationship between the red cell content and the electrical conductivity of blood. In a pilot study of 170 blood samples, a correlation coefficient of 0,9806 was obtained ...

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

Indian Academy of Sciences (India)

We have constructed a dual trap optical tweezers set-up around an inverted microscope where both the traps can be independently controlled and manipulated in all the three dimensions. Here we report our observations on rotation of red blood cells (RBCs) in a linearly polarized optical trap. Red blood cells deform and ...

Target molecular weights for red cell band 3 stilbene and mercurial binding sites

International Nuclear Information System (INIS)

Verkman, A.S.; Skorecki, K.L.; Jung, C.Y.; Ausiello, D.A.

1986-01-01

Radiation inactivation was used to measure the target sizes for binding of disulfonic stilbene anion transport inhibitor 4,4'-dibenzamido-2,2'-disulfonic stilbene (DBDS) and mercurial water transport inhibitor p-chloromercuribenzene sulfonate (pCMBS) to human erythrocytes. The measured target size for erythrocyte ghost acetylcholinesterase was 78 +/- 3 kDa. DBDS binding to ghost membranes was measured by a fluorescence enhancement technique. Radiation (0-26 Mrad) had no effect on total membrane protein and DBDS binding affinity, whereas DBDS binding stoichiometry decreased exponentially with radiation dose, giving a target size of 59 +/- 4 kDa. H2-4,4'-diisothiocyano-2,2'-disulfonic stilbene (H2-DIDS, 5 microM) blocked greater than 95% of DBDS binding at all radiation doses. pCMBS binding was measured from the time course of tryptophan fluorescence quenching in ghosts treated with the sulfhydryl reagent N-ethylmaleimide (NEM). Radiation did not affect the kinetics of tryptophan quenching, whereas the total amplitude of the fluorescence signal inactivated with radiation with a target size of 31 +/- 6 kDa. These results support the notion that DBDS and pCMBS bind to the transmembrane domain of erythrocyte band 3 in NEM-treated ghosts and demonstrate that radiation inactivation may probe a target significantly smaller than a covalently linked protein subunit. The small target size for the band 3 stilbene binding site may correspond to the intramembrane domain of the band 3 monomer (52 kDa), which is physically distinct from the cytoplasmic domain (42 kDa)

Graded band-gap engineering for increased efficiency in CZTS solar cells

Science.gov (United States)

Ferhati, H.; Djeffal, F.

2018-02-01

In this paper, we propose a potential high efficiency Cu2ZnSn(S,Se)4/CdS (CZTS) solar cell design based on graded band-gap engineering that can offer the benefits of improved absorption behavior and reduced recombination effects. Moreover, a new hybrid approach based on analytical modeling and Particle Swarm Optimization (PSO) is proposed to determinate the optimal band-gap profile of the amended CZTS absorber layer to achieve further efficiency enhancement. It is found that the proposed design exhibits superior performance, where a high efficiency of 16.9% is recorded for the optimized solar cell with a relative improvement of 92%, compared with the reference cell efficiency of 8.8%. Likewise, the optimized CZTS solar cell with a graded band-gap enables achieving a higher open circuit voltage of 889 mV, a short-circuit current of 28.5 mA and a fill factor of 66%. Therefore, the optimized CZTS-based solar cell with graded-band gap paradigm pinpoints a new path toward recording high-efficiency thin-film solar cells through enhancing carrier collection and reducing the recombination rate.

Survival of transfused red blood cells: In vivo compatibility testing with chromium-51

International Nuclear Information System (INIS)

Dharkar, D.D.; Pineda, A.A.

1983-01-01

The /sup 51/Cr red cell survival test and specific test for measurement of the disappearance rate of labeled red cells. This procedure can be used for the assessment of red cell compatibility testing in vivo. The authors recommend that more routine transfusions as well as ''difficult'' transfusions be monitored by /sup 51/Cr in vivo compatibility testing before the actual transfusions, so that more consistent and reliable survival values are achieved

EVALUATION OF ANAEMIA USING RED CELL AND RETICULOCYTE PARAMETERS USING AUTOMATED HAEMATOLOGY ANALYSER

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Vidyadhar Rao

2016-06-01

Full Text Available Use of current models of Automated Haematology Analysers help in calculating the haemoglobin contents of the mature Red cells, Reticulocytes and percentages of Microcytic and hypochromic Red cells. This has helped the clinician in reaching early diagnosis and management of Different haemopoietic disorders like Iron Deficiency Anaemia, Thalassaemia and anaemia of chronic diseases. AIM This study is conducted using an Automated Haematology Analyser to evaluate anaemia using the Red Cell and Reticulocyte parameters. Three types of anaemia were evaluated; iron deficiency anaemia, anaemia of long duration and anaemia associated with chronic disease and Iron deficiency. MATERIALS AND METHODS The blood samples were collected from 287 adult patients with anaemia differentiated depending upon their iron status, haemoglobinopathies and inflammatory activity. Iron deficiency anaemia (n=132, anaemia of long duration (ACD, (n=97 and anaemia associated with chronic disease with iron deficiency (ACD Combi, (n=58. Microcytic Red cells, hypochromic red cells percentage and levels of haemoglobin in reticulocytes and matured RBCs were calculated. The accuracy of the parameters was analysed using receiver operating characteristic analyser to differentiate between the types of anaemia. OBSERVATIONS AND RESULTS There was no difference in parameters between the iron deficiency group or anaemia associated with chronic disease and iron deficiency. The hypochromic red cells percentage was the best parameter in differentiating anaemia of chronic disease with or without absolute iron deficiency with a sensitivity of 72.7% and a specificity of 70.4%. CONCLUSIONS The parameters of red cells and reticulocytes were of reasonably good indicators in differentiating the absolute iron deficiency anaemia with chronic disease.

Screening hypochromism (sieve effect) in red blood cells: a quantitative analysis.

Science.gov (United States)

Razi Naqvi, K

2014-04-01

Multiwavelength UV-visible spectroscopy, Kramers-Kronig analysis, and several other experimental and theoretical tools have been applied over the last several decades to fathom absorption and scattering of light by suspensions of micron-sized pigmented particles, including red blood cells, but a satisfactory quantitative analysis of the difference between the absorption spectra of suspension of intact and lysed red blood cells is still lacking. It is stressed that such a comparison is meaningful only if the pertinent spectra are free from, or have been corrected for, scattering losses, and it is shown that Duysens' theory can, whereas that of Vekshin cannot, account satisfactorily for the observed hypochromism of suspensions of red blood cells.

Ferritin associates with marginal band microtubules

International Nuclear Information System (INIS)

Infante, Anthony A.; Infante, Dzintra; Chan, M.-C.; How, P.-C.; Kutschera, Waltraud; Linhartova, Irena; Muellner, Ernst W.; Wiche, Gerhard; Propst, Friedrich

2007-01-01

We characterized chicken erythrocyte and human platelet ferritin by biochemical studies and immunofluorescence. Erythrocyte ferritin was found to be a homopolymer of H-ferritin subunits, resistant to proteinase K digestion, heat stable, and contained iron. In mature chicken erythrocytes and human platelets, ferritin was localized at the marginal band, a ring-shaped peripheral microtubule bundle, and displayed properties of bona fide microtubule-associated proteins such as tau. Red blood cell ferritin association with the marginal band was confirmed by temperature-induced disassembly-reassembly of microtubules. During erythrocyte differentiation, ferritin co-localized with coalescing microtubules during marginal band formation. In addition, ferritin was found in the nuclei of mature erythrocytes, but was not detectable in those of bone marrow erythrocyte precursors. These results suggest that ferritin has a function in marginal band formation and possibly in protection of the marginal band from damaging effects of reactive oxygen species by sequestering iron in the mature erythrocyte. Moreover, our data suggest that ferritin and syncolin, a previously identified erythrocyte microtubule-associated protein, are identical. Nuclear ferritin might contribute to transcriptional silencing or, alternatively, constitute a ferritin reservoir

Rett Syndrome Mutant Neural Cells Lacks MeCP2 Immunoreactive Bands.

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Carlos Bueno

Full Text Available Dysfunctions of MeCP2 protein lead to various neurological disorders such as Rett syndrome and Autism. The exact functions of MeCP2 protein is still far from clear. At a molecular level, there exist contradictory data. MeCP2 protein is considered a single immunoreactive band around 75 kDa by western-blot analysis but several reports have revealed the existence of multiple MeCP2 immunoreactive bands above and below the level where MeCP2 is expected. MeCP2 immunoreactive bands have been interpreted in different ways. Some researchers suggest that multiple MeCP2 immunoreactive bands are unidentified proteins that cross-react with the MeCP2 antibody or degradation product of MeCP2, while others suggest that MeCP2 post-transcriptional processing generates multiple molecular forms linked to cell signaling, but so far they have not been properly analyzed in relation to Rett syndrome experimental models. The purpose of this study is to advance understanding of multiple MeCP2 immunoreactive bands in control neural cells and p.T158M MeCP2e1 mutant cells. We have generated stable wild-type and p.T158M MeCP2e1-RFP mutant expressing cells. Application of N- and C- terminal MeCP2 antibodies, and also, RFP antibody minimized concerns about nonspecific cross-reactivity, since they react with the same antigen at different epitopes. We report the existence of multiple MeCP2 immunoreactive bands in control cells, stable wild-type and p.T158M MeCP2e1-RFP mutant expressing cells. Also, MeCP2 immunoreactive bands differences were found between wild-type and p.T158M MeCP2e1-RFP mutant expressing cells. Slower migration phosphorylated band around 70kDa disappeared in p.T158M MeCP2e1-RFP mutant expressing cells. These data suggest that threonine 158 could represent an important phosphorylation site potentially involved in protein function. Our results clearly indicate that MeCP2 antibodies have no cross-reactivity with similar epitopes on others proteins, supporting the

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

NARCIS (Netherlands)

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

1993-01-01

In the present literature on ektacytometry, small angle light scattering by ellipsoidal red blood cells is commonly approximated by Fraunhofer diffraction. Calculations on a sphere with the size and relative refractive index of a red cell, however, show that Fraunhofer diffraction deviates

The convective photosphere of the red supergiant CE Tauri. I. VLTI/PIONIER H-band interferometric imaging

Science.gov (United States)

Montargès, M.; Norris, R.; Chiavassa, A.; Tessore, B.; Lèbre, A.; Baron, F.

2018-06-01

Context. Red supergiant stars are one of the latest stages in the evolution of massive stars. Their photospheric convection may play an important role in the launching mechanism of their mass loss; however, its characteristics and dynamics are still poorly constrained. Aims: By observing red supergiant stars with near infrared interferometry at different epochs, we expect to reveal the evolution of bright convective features on their stellar surface. Methods: We observed the M2Iab-Ib red supergiant star CE Tau with the VLTI/PIONIER instrument in the H band at two different epochs separated by one month. Results: We derive the angular diameter of the star and basic stellar parameters, and reconstruct two reliable images of its H-band photosphere. The contrast of the convective pattern of the reconstructed images is 5 ± 1% and 6 ± 1% for our two epochs of observation. Conclusions: The stellar photosphere shows few changes between the two epochs. The contrast of the convective pattern is below the average contrast variations obtained on 30 randomly chosen snapshots of the best matching 3D radiative hydrodynamics simulation: 23 ± 1% for the original simulation images and 16 ± 1% for the maps degraded to the reconstruction resolution. We offer two hypotheses to explain this observation. CE Tau may be experiencing a quiet convective activity episode or it could be a consequence of its warmer effective temperature (hence its smaller radius) compared to the simulation. Based on observations collected at the European Organisation for Astronomical Research in the Southern Hemisphere under ESO programs 298.D-5005(A) and 298.D-5005(B).Reconstructed images as FITS files and basic stellar parameters are available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/614/A12Animated gif of the two epochs is available at http://https://www.aanda.org

Effect of high dose irradiation on the red cell span in rabbits

International Nuclear Information System (INIS)

Kang, T.W.; Koh, J.W.; Woo, K.S.; Lee, O.H.; Youn, C.S.

1982-01-01

As a part of studies on acute effects of high dose irradiation in vivo, the present report was carried out to evaluate the changes of the red cell life span in the white rabbits by a single whole body exposure to gamma rays from 60 Co teletherapy unit. The exposure was done in dose levels of 100, 600 and 900 rads to each experimental group of 10 rabbits. The life span apparent half survival time of red cells, and that the red cell volume in the circulting blood were measured by ICSH Reference method using 51 Cr. (Author)

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

International Nuclear Information System (INIS)

Hua-Bing, Li; Li, Jin; Bing, Qiu

2008-01-01

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

Mechanical and electrical properties of red blood cells using optical tweezers

International Nuclear Information System (INIS)

Fontes, A; Castro, M L Barjas; Brandão, M M; Fernandes, H P; Huruta, R R; Costa, F F; Saad, S T O; Thomaz, A A; Pozzo, L Y; Barbosa, L C; Cesar, C L

2011-01-01

Optical tweezers are a very sensitive tool, based on photon momentum transfer, for individual, cell by cell, manipulation and measurements, which can be applied to obtain important properties of erythrocytes for clinical and research purposes. Mechanical and electrical properties of erythrocytes are critical parameters for stored cells in transfusion centers, immunohematological tests performed in transfusional routines and in blood diseases. In this work, we showed methods, based on optical tweezers, to study red blood cells and applied them to measure apparent overall elasticity, apparent membrane viscosity, zeta potential, thickness of the double layer of electrical charges and adhesion in red blood cells

Artificial Red Cells with Polyhemoglobin Membranes.

Science.gov (United States)

1981-09-01

Y. Reciprocal binding of oxygen and diphosphoglycerate by human hemoglobin. Proc. Natl. Acad. Sci. USA 59:526-532, 1968. 12. Bunn, H. F., Seal, U. S...and Scott, A. F. The role of 2,3- diphosphoglycerate in mediating hemoglobin function of mammalian red cells. Ann. N.Y. Acad. Sciences 241:498-519

Cermet based metamaterials for multi band absorbers over NIR to LWIR frequencies

International Nuclear Information System (INIS)

Pradhan, Jitendra K; Behera, Gangadhar; Anantha Ramakrishna, S; Agarwal, Amit K; Ghosh, Amitava

2017-01-01

Cermets or ceramic-metals are known for their use in solar thermal technologies for their absorption across the solar band. Use of cermet layers in a metamaterial perfect absorber allows for flexible control of infra-red absorption over the short wave infra-red, to long wave infra-red bands, while keeping the visible/near infra-red absorption properties constant. We design multilayered metamaterials consisting of a conducting ground plane, a low metal volume fraction cermet/ZnS as dielectric spacer layers, and a top structured layer of an array of circular discs of metal/high volume metal fraction cermet that give rise to specified absorption bands in the near-infra-red (NIR) frequencies, as well as any specified band at SWIR–LWIR frequencies. Thus, a complete decoupling of the absorption at optical/NIR frequencies and the infra-red absorption behaviour of a structured metamaterial is demonstrated. (paper)

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

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

Near infrared light induces post-translational modifications of human red blood cell proteins.

Science.gov (United States)

Walski, Tomasz; Dyrda, Agnieszka; Dzik, Małgorzata; Chludzińska, Ludmiła; Tomków, Tomasz; Mehl, Joanna; Detyna, Jerzy; Gałecka, Katarzyna; Witkiewicz, Wojciech; Komorowska, Małgorzata

2015-11-01

There is a growing body of evidence that near infrared (NIR) light exerts beneficial effects on cells. Its usefulness in the treatment of cancer, acute brain injuries, strokes and neurodegenerative disorders has been proposed. The mechanism of the NIR action is probably of photochemical nature, however it is not fully understood. Here, using a relatively simple biological model, human red blood cells (RBCs), and a polychromatic non-polarized light source, we investigate the impact of NIR radiation on the oxygen carrier, hemoglobin (Hb), and anion exchanger (AE1, Band 3). The exposure of intact RBCs to NIR light causes quaternary transitions in Hb, dehydration of proteins and decreases the amount of physiologically inactive methemoglobin, as detected by Raman spectroscopy. These effects are accompanied by a lowering of the intracellular pH (pHi) and changes in the cell membrane topography, as documented by atomic force microscopy (AFM). All those changes are in line with our previous studies where alterations of the membrane fluidity and membrane potential were attributed to NIR action on RBCs. The rate of the above listed changes depends strictly on the dose of NIR light that the cells receive, nonetheless it should not be considered as a thermal effect.

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 ...

Mechanism of Na,K-ATPase decline during sheep red cell maturation

Energy Technology Data Exchange (ETDEWEB)

Grafova, E.; Blostein, R.

1987-05-01

Na,K-ATPase of immature and mature sheep red cells of both the high-K/sup +/ and low-K/sup +/ genotypes as well as cells of both types matured in vitro was detected using polyclonal antiserum to sheep kidney Na,K-ATPase. Following SDS-PAGE and immunoblotting, the major reactive component was the approx. 100 kDa catalytic ..cap alpha.. subunit. A less prominent band migrating as a sharper, lower molecular weight (50 kDa) component than the kidney Na,K-ATPase ..beta.. subunit is apparent in reticulocytes but not mature cells. Membranes from both genotypes showed identical immunologically reactive peptides, except for the lower intensity of the ..cap alpha.. subunit in the mature cells of the low- compared to high-K/sup +/ sheep. Following culture of both types, moderate reduction in reactivity was apparent. Immunologically reactive ..cap alpha.. subunit as well as the 50 kDa species were detected in membranous material shed into the culture medium. This material was functionally inactive (lack of both (/sup 3/H) ouabain binding and Na/sup +/-dependent phosphorylation of Na,K-ATPase). The existence in reticulocytes of an intracellular pool of ouabain binding sites is evidenced in appearance of extra sites following rapid ATP depletion and also after addition of chloroquine. Taken together, these findings are consistent with a maturation-associated decrease of sodium pumps by a process of membrane recycling, processing and, to some extent, exocytosis.

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

Directory of Open Access Journals (Sweden)

Radoslav Dekić

2013-02-01

Full Text Available The paper presents the morphometric characteristics of red blood cells of endemic fish species of Bosnia and Herzegovina, Telestes metohiensis (Steindachner, 1901 inhabiting the Vrijeka river in the Dabar field. A total of 30 fish were sampled during August, 2010. Morphological measurements included the following parameters: axes of the red blood cells and nuclei, the surface of the red blood cells and nuclei and the thickness of the red blood cells. Morphometric characteristics of the erythrocyte maturation stages (acidophilic and polychromatic erythroblasts were also studied as well as their proportion in the peripheral blood. 100 mature forms were measured for each individual. The propotion of the immature forms was expressed per 1000 erythrocytes. Results showed that dimensions of the erythrocytes differed in systematic categories as well as fish types. Dimensions of mature erythrocytes and their maturation stages of the same species differed in shape and size of the nuclei. Proportion of the erythrocyte maturation stages was very low in comparison with the mature erythrocytes, indicating the optimal environmental conditions for the studied species.Key words: morphometric characteristics, erythrocytes, Telestes metohiensis, proportion of immature stages

Long-term culture and differentiation of porcine red bone marrow hematopoietic cells co-cultured with immortalized mesenchymal cells.

Science.gov (United States)

Garba, Abubakar; Acar, Delphine D; Roukaerts, Inge D M; Desmarets, Lowiese M B; Devriendt, Bert; Nauwynck, Hans J

2017-09-01

Mesenchymal cells are multipotent stromal cells with self-renewal, differentiation and immunomodulatory capabilities. We aimed to develop a co-culture model for differentiating hematopoietic cells on top of immortalized mesenchymal cells for studying interactions between hematopoietic and mesenchymal cells, useful for adequately exploring the therapeutic potential of mesenchymal cells. In this study, we investigated the survival, proliferation and differentiation of porcine red bone marrow hematopoietic cells co-cultured with immortalized porcine bone marrow mesenchymal cells for a period of five weeks. Directly after collection, primary porcine bone marrow mesenchymal cells adhered firmly to the bottom of the culture plates and showed a fibroblast-like appearance, one week after isolation. Upon immortalization, porcine bone marrow mesenchymal cells were continuously proliferating. They were positive for simian virus 40 (SV40) large T antigen and the mesenchymal cell markers CD44 and CD55. Isolated red bone marrow cells were added to these immortalized mesenchymal cells. Five weeks post-seeding, 92±6% of the red bone marrow hematopoietic cells were still alive and their number increased 3-fold during five weekly subpassages on top of the immortalized mesenchymal cells. The red bone marrow hematopoietic cells were originally small and round; later, the cells increased in size. Some of them became elongated, while others remained round. Tiny dendrites appeared attaching hematopoietic cells to the underlying immortalized mesenchymal cells. Furthermore, weekly differential-quick staining of the cells indicated the presence of monoblasts, monocytes, macrophages and lymphocytes in the co-cultures. At three weeks of co-culture, flow cytometry analysis showed an increased surface expression of CD172a, CD14, CD163, CD169, CD4 and CD8 up to 37±0.8%, 40±8%, 41±4%, 23±3% and 19±5% of the hematopoietic cells, respectively. In conclusion, continuous mesenchymal cell

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

DEFF Research Database (Denmark)

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

2014-01-01

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

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

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Calibrator for red cell and white cell counting. 864.8185 Section 864.8185 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Reagents § 864.8185...

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.

F NMR measurement of intracellular free calcium in human red blood cells

International Nuclear Information System (INIS)

Gupta, R.K.; Schanne, F.A.X.

1986-01-01

Optical techniques for the measurement of intracellular Ca are not readily applicable to the human red cell because of the intense absorption of hemoglobin. The authors have therefore examined the use of 19 F NMR of 5,5'-difluoro-1,2-bis(o-aminophenoxy) ethane-N,N,N',N'-tetra acetic acid (5FBAPTA) introduced non-disruptively by intracellular hydrolysis of the membrane-permeant acetoxymethyl ester derivative. 19 F NMR spectra of 5FBAPTA-containing erythrocytes at 188 MHz displayed two well resolved resonances corresponding to the free and Ca-bound forms of the chelator, the resonance of the free form being ten-fold larger than that of the Ca-bound form. Addition of the ionophore A23187 resulted in the disappearance of the resonance of the free anion and a quantitative increase in the intensity of the resonance of the Ca-complex. From these data, and a K/sub D/ of 708 nM for the Ca-5FBAPTA complex, the authors estimate red cell free Ca to be 70 nM, which is in the range of values obtained for other cells, despite the fact that the human red cell, which lacks intracellular organelles for storing Ca, possesses only 1 μmol total Ca/1. cells in comparison to mmols of total Ca found in other cells. The authors ability to use 19 F NMR to measure free Ca in the red blood cell paves the way for future NMR studies of red cell free Ca concentrations in human essential hypertension as well as in other diseases states in which alterations in cellular Ca homeostasis may be involved

Nature of the elements transporting long-chain fatty acids through the red cell membrane

DEFF Research Database (Denmark)

Bojesen, Inge Norby; Bojesen, Eigil

1998-01-01

Docosahexaenoic acid, linoleic acid, red cell membrane, transporting elements, transport kinetics, fatty acid transport......Docosahexaenoic acid, linoleic acid, red cell membrane, transporting elements, transport kinetics, fatty acid transport...

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...

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

Does the band cell survive the 21st century?

NARCIS (Netherlands)

Meer, W. van der; Gelder, W. van; Keijzer, R. de; Willems, H.

2006-01-01

OBJECTIVES: The differentiation of white blood cells is a worldwide-accepted method to obtain medical information. The conventional microscopic differential, however, is a laborious and expensive test with a low statistical value. Especially for band cell identification there is a wide range of

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.

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

Science.gov (United States)

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

2012-03-01

Blood transfusion is indispensable for modern medicine. In developed countries, the blood supply is adequate and safe but blood for alloimmunized patients is often unavailable. Concerns are increasing that donations may become inadequate in the future as the population ages prompting a search for alternative transfusion products. Improvements in culture conditions and proof-of-principle studies in animal models have suggested that ex-vivo expanded red cells may represent such a product. Compared to other cell therapies transfusion poses the unique challenge of requiring great cell doses (2.5×10(12) cells vs 10(7) cells). Although production of such cell numbers is theoretically possible, current technologies generate red cells in numbers sufficient only for safety studies. It is conceived that by the time these studies will be completed, technical barriers to mass cell production will have been eliminated making transfusion with ex-vivo generated red cells a reality. Copyright © 2011 Elsevier Ltd. All rights reserved.

Image-based model of the spectrin cytoskeleton for red blood cell simulation.

Science.gov (United States)

Fai, Thomas G; Leo-Macias, Alejandra; Stokes, David L; Peskin, Charles S

2017-10-01

We simulate deformable red blood cells in the microcirculation using the immersed boundary method with a cytoskeletal model that incorporates structural details revealed by tomographic images. The elasticity of red blood cells is known to be supplied by both their lipid bilayer membranes, which resist bending and local changes in area, and their cytoskeletons, which resist in-plane shear. The cytoskeleton consists of spectrin tetramers that are tethered to the lipid bilayer by ankyrin and by actin-based junctional complexes. We model the cytoskeleton as a random geometric graph, with nodes corresponding to junctional complexes and with edges corresponding to spectrin tetramers such that the edge lengths are given by the end-to-end distances between nodes. The statistical properties of this graph are based on distributions gathered from three-dimensional tomographic images of the cytoskeleton by a segmentation algorithm. We show that the elastic response of our model cytoskeleton, in which the spectrin polymers are treated as entropic springs, is in good agreement with the experimentally measured shear modulus. By simulating red blood cells in flow with the immersed boundary method, we compare this discrete cytoskeletal model to an existing continuum model and predict the extent to which dynamic spectrin network connectivity can protect against failure in the case of a red cell subjected to an applied strain. The methods presented here could form the basis of disease- and patient-specific computational studies of hereditary diseases affecting the red cell cytoskeleton.

Mathematical analysis of 51Cr-labelled red cell survival curves in congenital haemolytic anaemias

International Nuclear Information System (INIS)

Kasfiki, A.G.; Antipas, S.E.; Dimitriou, P.A.; Gritzali, F.A.; Melissinos, K.G.

1982-01-01

The parameters of 51 Cr labelled red cell survival curves were calculated in 26 patients with homozygous β-thalassaemia, 8 with sickle-cell anaemia and 3 with s-β-thalassaemia, using a non-linear weighted least squares analysis computer program. In thalassaemic children the calculated parameters denote that the shorting of the mean cell life is due to early senescence alone, while there is some evidence that in thalassaemic adults additional extracellular destruction mechanisms participate as well. Red cell survival curves from patients with sickle-cell anaemia and s-β-thalassaemia resemble each other, while their parameters indicate an initial rapid loss of radioactivity, early senescence and the presence of extracellular red cell destruction factors. (orig.)

Cation Homeostasis in Red Cells From Patients With Sickle Cell Disease Heterologous for HbS and HbC (HbSC Genotype

Directory of Open Access Journals (Sweden)

A. Hannemann

2015-11-01

Full Text Available Sickle cell disease (SCD in patients of HbSC genotype is considered similar, albeit milder, to that in homozygous HbSS individuals — but with little justification. In SCD, elevated red cell cation permeability is critical as increased solute loss causes dehydration and encourages sickling. Recently, we showed that the KCl cotransporter (KCC activity in red cells from HbSC patients correlated significantly with disease severity, but that in HbSS patients did not. Two transporters involved in red cell dehydration, the conductive channels Psickle and the Gardos channel, behaved similarly in red cells from the two genotypes, but were significantly less active in HbSC patients. By contrast, KCC activity was quantitatively greater in HbSC red cells. Results suggest that KCC is likely to have greater involvement in red cell dehydration in HbSC patients, which could explain its association with disease severity in this genotype. This work supports the hypothesis that SCD in HbSC patients is a distinct disease entity to that in HbSS patients. Results suggest the possibility of designing specific treatments of particular benefit to HbSC patients and a rationale for the development of prognostic markers, to inform early treatment of children likely to develop more severe complications of the disease.

Liquid Storage at 4 deg C of Previously Frozen Red Cells

Science.gov (United States)

1987-12-01

adenosine tnphosphate (ATP). 2.3- acceptable red cell function. A post-thaw storage ca- diphosphoglycerate (2.3-DPG), glucose, supernatant hemo...and Received for publication September 22. 1986; revision received supernatant hemoglobin levels within the acceptable range, November 29, 1986, and...percent. All units were sterile at the end of the 21-day post- thaw storage period. 6.9 The mean red cell ATP and 2,3-DPG levels are shown in Figure 1

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

Science.gov (United States)

Bitensky, M.W.; Yoshida, Tatsuro

1997-04-29

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

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

Science.gov (United States)

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

2014-01-01

Here we investigated alterations in the protein profile of Hep-2 treated with red propolis using two-dimensional electrophoresis associated to mass spectrometry and apoptotic rates of cells treated with and without red propolis extracts through TUNEL and Annexin-V assays. A total of 325 spots were manually excised from the two-dimensional gel electrophoresis and 177 proteins were identified using LC-MS-MS. Among all proteins identified that presented differential expression, most were down-regulated in presence of red propolis extract at a concentration of 120 μg/mL (IC50): GRP78, PRDX2, LDHB, VIM and TUBA1A. Only two up-regulated proteins were identified in this study in the non-cytotoxic (6 μg/mL) red propolis treated group: RPLP0 and RAD23B. TUNEL staining assay showed a markedly increase in the mid- to late-stage apoptosis of Hep-2 cells induced by red propolis at concentrations of 60 and 120 μg/mL when compared with non-treated cells. The increase of late apoptosis was confirmed by in situ Annexin-V analysis in which red propolis extract induced late apoptosis in a dose-dependent manner. The differences in tumor cell protein profiles warrant further investigations including isolation of major bioactive compounds of red propolis in different cell lines using proteomics and molecular tests to validate the protein expression here observed. Copyright © 2013 Elsevier Ltd. All rights reserved.

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.

Clinical Utility of Red Cell Distribution Width in Alcoholic and Non-alcoholic Liver Cirrhosis

OpenAIRE

Milić, Sandra; Mikolašević, Ivana; Radić, Mladen; Hauser, Goran; Štimac, Davor

2011-01-01

Red blood cell distribution width (RDW) is a measure of the variation of red blood cell width that is reported as a part of standard complete blood count. Red blood cell distribution width results are often used together with mean corpuscular volume (MCV) results to figure out mixed anemia. The aim of our study was to compare the values of RDW in alcoholic and non-alcoholic liver cirrhosis and to determine if RDW follows the severity of disease according to Child-Pugh score. We re...

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

Training the next generation analyst using red cell analytics

Science.gov (United States)

Graham, Meghan N.; Graham, Jacob L.

2016-05-01

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

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....

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.

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

International Nuclear Information System (INIS)

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

1985-01-01

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

Measurement of the viability of stored red cells by the single-isotope technique using 51Cr. Analysis of validity

International Nuclear Information System (INIS)

Beutler, E.; West, C.

1984-01-01

A single-isotope 51 Cr method often is used to evaluate the viability of stored red cells. In this technique, the red cell mass is measured by back-extrapolation to time zero (t0) of the radioactivity of the blood between 5 and 20 minutes after infusion of the sample. If there is early destruction of stored cells, this method provides an overestimate of the red cell mass and, hence, of the viability of the stored cells. Freshly drawn red cells from normal donors were labeled with /sup 99m/Tc, and cells from the same donor which had been stored in citrate-phosphate-dextrose-adenine-one (CPDA-1) for periods ranging from 7 to 49 days were labeled with 51 Cr. A comparison of the ''true red cell mass'' as determined with /sup 99m/Tc with the back-extrapolated red cell mass from stored 51 Cr-labeled cells has made it possible to define the magnitude of error introduced by early loss of red cells. The overestimation of red cell mass and viability was diminished if only the 51 Cr radioactivity between 5 and 15 minutes after infusion was used in back-extrapolating to t0. The degree of overestimation of red cell mass was greatest when the red cell viability had declined to very low levels. However, in the entire range of 10 to 80 percent viability, the overestimate of viability was usually less than 4 percent. The overestimate of viability proved to be quite similar for all samples and may be taken into account when using the single-isotope technique for measurement of red cell viability

Bone scan and red blood cell scan in a patient with epidermal naevus syndrome

International Nuclear Information System (INIS)

Becker, W.; Wolf, F.; Stosiek, N.; Peters, K.P.

1990-01-01

A bone scan and red blood cell scan in the rare epidermal naevus syndrome, associated with multiple haemangiomes of the bone and hypophosphataemic osteomalacia in a 20-year-old man are reported. The typical pattern of osteomalacia on the bone scan was associated with lesions of increased bone metabolism in the peripheral bones. The haemangiomas did not pool labelled red blood cells. Thus, the bone scan seems to be suited for diagnosing the complete extent of haemangiomas in bone, but they could not be specifically proven by red blood cell pooling. (orig.)

Effect of N′-nitrosodimethylamine on red blood cell rheology and proteomic profiles of brain in male albino rats

Science.gov (United States)

Ahmad, Areeba; Fatima, Ravish; Maheshwari, Veena; Ahmad, Riaz

2011-01-01

We investigated the effects of N'-nitrosodimethylamine (NDMA) induced toxicity on red blood cell rheology in male rats and identified bands in proteomic profiles of brain which can be used as novel markers. Polyacrylamide gel electrophoresis (PAGE) profiles exhibited constitutive as well as induced expression of the polypeptides. Remarkably, the molecular weight range of the polypeptides (8–150 kDa) corresponded to that of the family of heat shock proteins. Our results revealed significant changes in blood parameters and showed the presence of acanthocytes, tear drop cells, spicules and cobot rings in the treated categories. Lactate dehydrogenase and esterase zymograms displayed a shift to anaerobic metabolism generating hypoxia-like conditions. This study strongly suggests that NDMA treatment causes acute toxicity leading to cell membrane destruction and alters protein profiles in rats. It is therefore recommended that caution should be exercised in using NDMA to avoid risks, and if at all necessary strategies should be designed to combat such conditions. PMID:22058653

Red Cell Indexes Made Easy Using an Interactive Animation: Do Students and Their Scores Concur?

Science.gov (United States)

Kachroo, Upasana; Vinod, Elizabeth; Balasubramanian, Sivakumar; W., Jesi; Prince, Neetu

2018-01-01

A good understanding of red cell indexes can aid medical students in a considerable manner, serving as a basis to unravel both concepts in red cell physiology and abnormalities associated with the same. In this study, we tried to assess whether an interactive animation was helpful in improving student comprehension and understanding of red cell…

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.

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.

Membrane transport of anandamide through resealed human red blood cell membranes

DEFF Research Database (Denmark)

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

2005-01-01

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

Quantitative analysis of UV excitation bands for red emissions in Pr3+-doped CaTiO3, SrTiO3 and BaTiO3 phosphors by peak fitting

International Nuclear Information System (INIS)

Fujiwara, Rei; Sano, Hiroyuki; Shimizu, Mikio; Kuwabara, Makoto

2009-01-01

A quantitative spectral analysis of the ultraviolet (UV) broad excitation bands, which are located in the range 300-400 nm, for red emissions at around 610 nm in Pr-doped CaTiO 3 , SrTiO 3 :Al and BaTiO 3 :Mg phosphors has been carried out using a peak fitting technique. The obtained results demonstrate that the UV broad band of CaTiO 3 :Pr consists of four primary excitation bands centered around 330, 335, 365 and 380 nm and those of both SrTiO 3 :Al and BaTiO 3 :Mg consist of three primary bands centered around 310, 345 and 370 nm. Based on the behavior patterns and the values of the respective primary excitation bands' parameters, i.e. center gravity (λ top ), maximum height (I max ) and full-width at half-maximum (FWHM), the UV-to-red relaxation processes in these titanate phosphors can be explained to be essentially the same, except for the existence of an additional relaxation pathway via electron-trap states in CaTiO 3 :Pr, which gives a characteristic shape of its UV excitation spectrum in the wavelength range of >360 nm

Nonreassuring fetal heart rate patterns and nucleated red blood cells in term neonates.

Science.gov (United States)

Kovalak, E Ebru; Dede, F Suat; Gelisen, Orhan; Dede, Hulya; Haberal, Ali

2011-05-01

The aim of this study was to evaluate the association between nonreassuring fetal heart rate patterns during labor and umbilical cord nucleated red blood cell counts. Nucleated red blood cell data was collected prospectively from 41 singleton term neonates presented with nonreassuring fetal heart rate patterns and/or meconium stained amniotic fluid during labor (study group) and from 45 term neonates without any evidence of nonreassuring fetal status (controls). Umbilical artery pH, blood gases and base excess were also determined to investigate the correlation between independent variables. The median nucleated red blood cells per 100 white blood cells were 13 (range 0-37) in the study group and 8 (range 0-21) in the control group. Stepwise regression analysis have identified meconium stained amniotic fluid (R(2) = 0.15, p patterns. Nucleated red blood cells in the cord blood of newborns were found to be elevated in patients with nonreassuring FHR patterns during labor. However, the wide range and the poor correlation of NRBC count with umbilical artery pH and blood gas values limit its clinical utility as a marker for fetal hypoxia.

Getting into the flow: Red cells go on a roll, two-component vesicles swing

Science.gov (United States)

Viallat, Annie; Dupire, Jules; Khelloufi, Kamel; Al Halifa, Al Hair; Adhesion and Inflammation Team

2013-11-01

Red blood cells are soft capsules. Under shear flow, their two known motions were ``tumbling'' and ``swinging-tank treading,'' depending on cell mechanics and flow conditions. We reveal new wobbling regimes, among which the ``rolling'' regime, where red cells move as wheels on a road. We show, by coupling two video-microscopy approaches providing multi-directional cell pictures that the orientation of cells flipping into the flow is determined by the shear rate. Rolling permits to avoid energetically costly cellular deformations and is a true signature of the cytoskeleton elasticity. We highlight two transient dynamics: an intermittent regime during the ``tank-treading-to-flipping'' transition and a Frisbee-like ``spinning'' regime during the ``rolling-to-tank-treading'' transition. We find that the biconcave red cell shape is very stable under moderate shear stresses, and we interpret this result in terms of shape memory and elastic buckling. Finally, we generate lipid vesicles with a shape memory by using two lipids with different bending rigidities. These vesicles swing in shear flow similarly to red blood cells but their non-axisymmetric stress-free shape changes the periodicity of the motion and induces specific features.

Relation of mean platelet volume and red blood cell distribution width with epistaxis.

Science.gov (United States)

Kemal, Ozgur; Müderris, Togay; Sevil, Ergün; Kutlar, Gökhan

2015-04-01

Mean platelet volume is the measurement of the average size of platelets in the blood, and red blood cell distribution width is the variability of the size of red blood cells in circulation. This study aimed to investigate if there was any relationship between mean platelet volume, red blood cell distribution, and epistaxis. Prospective controlled trial. The study included 90 patients admitted to Ankara Atatürk Hospital and Samsun Medicana Hospital with complaints of recurrent epistaxis, and a control group of 90 healthy subjects. Blood samples were taken from all patients and control group subjects. Mean platelet volume and red blood cell distribution parameters were examined and compared between the two groups. The mean platelet volume levels were determined as 8.86 ± 0.1 in the control group and 8.36 ± 0.1 in the patient group. The difference between the two groups with respect to mean platelet volume was statistically significant (P epistaxis. These findings could be beneficial in new investigations into epistaxis mechanisms. © 2014 The American Laryngological, Rhinological and Otological Society, Inc.

Anatomical features of pepper plants (Capsicum annuum L.) grown under red light-emitting diodes supplemented with blue or far-red light

Science.gov (United States)

Schuerger, A. C.; Brown, C. S.; Stryjewski, E. C.

1997-01-01

Pepper plants (Capsicum annuum L. cv., Hungarian Wax) were grown under metal halide (MH) lamps or light-emitting diode (LED) arrays with different spectra to determine the effects of light quality on plant anatomy of leaves and stems. One LED (660) array supplied 90% red light at 660 nm (25nm band-width at half-peak height) and 1% far-red light between 700-800nm. A second LED (660/735) array supplied 83% red light at 660nm and 17% far-red light at 735nm (25nm band-width at half-peak height). A third LED (660/blue) array supplied 98% red light at 660nm, 1% blue light between 350-550nm, and 1% far-red light between 700-800nm. Control plants were grown under broad spectrum metal halide lamps. Plants were gron at a mean photon flux (300-800nm) of 330 micromol m-2 s-1 under a 12 h day-night photoperiod. Significant anatomical changes in stem and leaf morphologies were observed in plants grown under the LED arrays compared to plants grown under the broad-spectrum MH lamp. Cross-sectional areas of pepper stems, thickness of secondary xylem, numbers of intraxylary phloem bundles in the periphery of stem pith tissues, leaf thickness, numbers of choloplasts per palisade mesophyll cell, and thickness of palisade and spongy mesophyll tissues were greatest in peppers grown under MH lamps, intermediate in plants grown under the 660/blue LED array, and lowest in peppers grown under the 660 or 660/735 LED arrays. Most anatomical features of pepper stems and leaves were similar among plants grown under 660 or 660/735 LED arrays. The effects of spectral quality on anatomical changes in stem and leaf tissues of peppers generally correlate to the amount of blue light present in the primary light source.

Characterization of the chlorophyll thermoluminescence afterglow in dark-adapted or far-red-illuminated plant leaves

International Nuclear Information System (INIS)

Miranda, T.; Ducruet, J.M.

1995-01-01

Far red illumination of photosynthetic material induces a delayed luminescence rise, or afterglow, which has been reported in plant leaves, protoplasts or intact chloroplasts and in algal cells. but does not occur in isolated thylakoids. The rise kinetics is accelerated by increasing temperature and we show, by slowly heating a leaf sample after a far-red illumination, that the afterglow emission can be optimally resolved as a sharp thermoluminescence band. Plant material was mainly pea (Pisum sativum L., cv Kazar and Merveille de Kelvedon) and cucumber (Cucumis sativus L., cv Marketer). Comparisons were done with rape, spinach, tobacco, avocado and maize. A 0.2 degree C-1s to 0.5 degree C-1s temperature gradient, started above 0 degree C after a far red illumination, revealed a new thermoluminescence AG band, peaking between 40 degree C and 50 degree C. It exhibited the characteristic properties of the luminescence afterglow recorded at a constant temperature. The AG band was very sensitive to short incubations at both freezing and moderately warm temperatures. Increasing duration of far red illumination caused two kinetically distinct effects on the AG band and on the B band (S-2S-3 Q-B- recombination), which can be ascribed to different behaviors of proton gradients in stroma and in grana lamellae, respectively. The induction of an afterglow by far red light lasted for several minutes in the dark, at 10 degree C. Flash sequences fired in these conditions confirmed the presence of S-2 and S-3 states stable in the dark, producing luminescence by recombination with back-transferred electrons. In some plant batches, an AG band could be induced by 2 or 3 flashes in the absence of far red light, which demonstrates that a metabolic state leading to AG emission may arise spontaneously in plant leaves. The strong temperature dependence of the AG emission is discussed in terms of heat-induced conformational changes in the thylakoid membrane. We conclude that

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...

The red and blue galaxy populations in the GOODS field: evidence for an excess of red dwarfs

Science.gov (United States)

Salimbeni, S.; Giallongo, E.; Menci, N.; Castellano, M.; Fontana, A.; Grazian, A.; Pentericci, L.; Trevese, D.; Cristiani, S.; Nonino, M.; Vanzella, E.

2008-01-01

Aims: We study the evolution of the galaxy population up to z˜ 3 as a function of its colour properties. In particular, luminosity functions and luminosity densities were derived as a function of redshift for the blue/late and red/early populations. Methods: We use data from the GOODS-MUSIC catalogue, which have typical magnitude limits z850≤ 26 and K_s≤ 23.5 for most of the sample. About 8% of the galaxies have spectroscopic redshifts; the remaining have well calibrated photometric redshifts derived from the extremely wide multi-wavelength coverage in 14 bands (from the U band to the Spitzer 8~ μm band). We have derived a catalogue of galaxies complete in the rest-frame B-band, which has been divided into two subsamples according to their rest-frame U-V colour (or derived specific star formation rate) properties. Results: We confirm a bimodality in the U-V colour and specific star formation rate of the galaxy sample up to z˜ 3. This bimodality is used to compute the luminosity functions of the blue/late and red/early subsamples. The luminosity functions of the blue/late and total samples are well represented by steep Schechter functions evolving in luminosity with increasing redshifts. The volume density of the luminosity functions of the red/early populations decreases with increasing redshift. The shape of the red/early luminosity functions shows an excess of faint red dwarfs with respect to the extrapolation of a flat Schechter function and can be represented by the sum of two Schechter functions. Our model for galaxy formation in the hierarchical clustering scenario, which also includes external feedback due to a diffuse UV background, shows a general broad agreement with the luminosity functions of both populations, the larger discrepancies being present at the faint end for the red population. Hints on the nature of the red dwarf population are given on the basis of their stellar mass and spatial distributions.

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

Directory of Open Access Journals (Sweden)

David Chiapaikeo

2015-03-01

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

FRET imaging of hemoglobin concentration in Plasmodium falciparum-infected red cells.

Directory of Open Access Journals (Sweden)

Alessandro Esposito

Full Text Available During its intraerythrocytic asexual reproduction cycle Plasmodium falciparum consumes up to 80% of the host cell hemoglobin, in large excess over its metabolic needs. A model of the homeostasis of falciparum-infected red blood cells suggested an explanation based on the need to reduce the colloid-osmotic pressure within the host cell to prevent its premature lysis. Critical for this hypothesis was that the hemoglobin concentration within the host cell be progressively reduced from the trophozoite stage onwards.The experiments reported here were designed to test this hypothesis by direct measurements of the hemoglobin concentration in live, infected red cells. We developed a novel, non-invasive method to quantify the hemoglobin concentration in single cells, based on Förster resonance energy transfer between hemoglobin molecules and the fluorophore calcein. Fluorescence lifetime imaging allowed the quantitative mapping of the hemoglobin concentration within the cells. The average fluorescence lifetimes of uninfected cohorts was 270+/-30 ps (mean+/-SD; N = 45. In the cytoplasm of infected cells the fluorescence lifetime of calcein ranged from 290+/-20 ps for cells with ring stage parasites to 590+/-13 ps and 1050+/-60 ps for cells with young trophozoites and late stage trophozoite/early schizonts, respectively. This was equivalent to reductions in hemoglobin concentration spanning the range from 7.3 to 2.3 mM, in line with the model predictions. An unexpected ancillary finding was the existence of a microdomain under the host cell membrane with reduced calcein quenching by hemoglobin in cells with mature trophozoite stage parasites.The results support the predictions of the colloid-osmotic hypothesis and provide a better understanding of the homeostasis of malaria-infected red cells. In addition, they revealed the existence of a distinct peripheral microdomain in the host cell with limited access to hemoglobin molecules indicating the

The effect of alpha-thalassemia on cord blood red cell indices and interaction with sickle cell gene

International Nuclear Information System (INIS)

Quadri, Mohammad I.; Islam, Sherief I.A.M.; Nasserullah, Z.

2000-01-01

Alpha-thalassemia is known to be prevalent in the Eastern region of Saudi Arabia. There are no large scale reports regarding the effect of alpha-thalassemia on red cell indices of cord blood from Saudi Arabia. Similarly, there are reports regarding the interaction of alpha-thalassemia and the sickle-cell gene in relation to red cell indices in cord blood. To address these issues, we undertook a study on neonatal cold blood samples. In a prospective study, cord blood samples from 504 neonates from the Qatif area of the Eastern Province of Saudi Arabia were analyzed for complete blood counts (CBC) and cellulose acetate Hb electrophoresis. Hb S was confirmed by citrate agar Hb electrophoresis. There were 243 case samples with normal Hb electrophoresis (Hb A 27.2+- 7% and Hb F 72.6+-7.7%). Their mean Hb (g/dL), RBC (x10/L), Hct (%), MCV (pg), MCHC (g/dL), RDW-SD (fl) and RDW-CV (%) were 15.05+-1.6, 4.5+-0.5, 47.4+-5.3, 106+-8, 33.6+-2.3, 31.8+-1.7, 69.2+-9.5 and 17.9+-1.7, respectively. There were 136 cases with alpha-thalassemia trait (alphaTT), 57 cases with sickle cell trait (SCT) and 50 cases of sickle cell trait with alplha-thalassemia trait (SCT/ alphaTT). There were ten cases of Hb H disease (6 definite), including one with sickle cell disease (SCD) and two with SCT, Hb Bart's 23.9%-43.6%; four probable with Hb Bart's 10.9%-16.1% and one with SCT. The effect on red cell parameters in Hb H disease were most pronounced. In addition, there seven cases of SCD, four of whom had coexistent alpha-thalassemia trait (SCD/alphaTT). The prevalence of alpha-thalassemia in this cohort of Saudi population was 39.99%. Hb H disease appeared as common as SCD. Sickle cell gene was seen in 23.4% of neonatal samples. Apha-thalassemia gene significantly reduces MCH, MCV, RDW-SD, Hct, Hb and increase RBC count in both normal or sickle cell trait neonates. Generally, the variation of red cell parameters is directly proportional to the amount of Hb Bart's in the cord blood. Sickle cell

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.

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

Physical-biological coupling induced aggregation mechanism for the formation of high biomass red tides in low nutrient waters.

Science.gov (United States)

Lai, Zhigang; Yin, Kedong

2014-01-01

Port Shelter is a semi-enclosed bay in northeast Hong Kong where high biomass red tides are observed to occur frequently in narrow bands along the local bathymetric isobars. Previous study showed that nutrients in the Bay are not high enough to support high biomass red tides. The hypothesis is that physical aggregation and vertical migration of dinoflagellates appear to be the driving mechanism to promote the formation of red tides in this area. To test this hypothesis, we used a high-resolution estuarine circulation model to simulate the near-shore water dynamics based on in situ measured temperature/salinity profiles, winds and tidal constitutes taken from a well-validated regional tidal model. The model results demonstrated that water convergence occurs in a narrow band along the west shore of Port Shelter under a combined effect of stratified tidal current and easterly or northeasterly wind. Using particles as dinoflagellate cells and giving diel vertical migration, the model results showed that the particles aggregate along the convergent zone. By tracking particles in the model predicted current field, we estimated that the physical-biological coupled processes induced aggregation of the particles could cause 20-45 times enhanced cell density in the convergent zone. This indicated that a high cell density red tide under these processes could be initialized without very high nutrients concentrations. This may explain why Port Shelter, a nutrient-poor Bay, is the hot spot for high biomass red tides in Hong Kong in the past 25 years. Our study explains why red tide occurrences are episodic events and shows the importance of taking the physical-biological aggregation mechanism into consideration in the projection of red tides for coastal management. Copyright © 2013 Elsevier B.V. All rights reserved.

Effect of laser light on the fragility and permeability of the red blood cell membrane

International Nuclear Information System (INIS)

El-Yassin, H. D.

2005-01-01

The resistance of red blood cells to hypotonic hemolysis is often characterized in terms of their osmotic fragility. The percentage of cells that hemolize when plotted as a function of different concentrations of NaCl forms fragility curve, which has a sigmoidal shape. In this study we show that the exposure of red blood cells to laser light converts the sigmoidal shape of the fragility curve to a hyperbolic one, which means that the old population of the red blood cells are the ones more affected by the light which cause their destruction. At the same time it seems that transport across the cell membrane is affected also. The biochemical and physiological implications of this finding are discussed. (author)

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

Science.gov (United States)

Bitensky, Mark W.; Yoshida, Tatsuro

1997-01-01

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

Calculation of Energy Band Diagram of a Photoelectrochemical Water Splitting Cell

OpenAIRE

Cendula, P.; Tilley, S. D.; Gimenez, S.; Schmid, M.; Bisquert, J.; Graetzel, M.; Schumacher, J. O.

2014-01-01

A physical model is presented for a semiconductor electrode of a photoelectrochemical (PEC) cell, accounting for the potential drop in the Helmholtz layer. Hence both band edge pinning and unpinning are naturally included in our description. The model is based on the continuity equations for charge carriers and direct charge transfer from the energy bands to the electrolyte. A quantitative calculation of the position of the energy bands and the variation of the quasi-Fermi levels in the semic...

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

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Shin-ichiro Suemori

2015-01-01

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

Development of III-Sb Quantum Dot Systems for High Efficiency Intermediate Band Solar Cells

Energy Technology Data Exchange (ETDEWEB)

Huffaker, Diana [Univ. of California, Los Angeles, CA (United States); Hubbard, Seth [Rochester Inst. of Technology, NY (United States); Norman, Andrew [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2015-07-31

This project aimed to develop solar cells that can help reduce cost per watt. This work focused on developing solar cells that utilize quantum dot (QD) nanomaterials to provide multijunction solar cell efficiency at the cost of single junction solar cell. We focused on a novel concept known as intermediate band solar cells (IBSC) where an additional energy band is inserted in a single solar cell to accommodate sub-bandgap photons absorption which otherwise are lost through transmission. The additional energy band can be achieved by growing QDs within a solar cell p-n junction. Though numerous studies have been conducted to develop such QD systems, very small improvements in solar energy conversion efficiency have been reported. This is mainly due to non-optimal material parameters such as band gap, band offset etc. In this work, we identified and developed a novel QD material system that meets the requirements of IBSC more closely than the current state-of-the-art technology. To achieve these goals, we focused on three important areas of solar cell design: band structure calculations of new materials, efficient device design for high efficiency, and development of new semiconductor materials. In this project, we focused on III-Sb materials as they possess a wide range of energy bandgaps from 0.2 eV to 2eV. Despite the difficulty involved in realizing these materials, we were successfully developed these materials through a systematic approach. Materials studied in this work are AlAsSb (Aluminum Arsenide Antimonide), InAlAs (Indium Aluminum Arsenide) and InAs (Indium Arsenide). InAs was used to develop QD layers within AlAsSb and InAlAs p-n junctions. As the QDs have very small volume, up to 30 QD layers been inserted into the p-n junction to enhance light absorption. These QD multi-stack devices helped in understanding the challenges associated with the development of quantum dot solar cells. The results from this work show that the quantum dot solar cells indeed

Interaction of different forms of graphene with chicken embryo red blood cells

DEFF Research Database (Denmark)

Jaworski, S.; Hinzmann, Mateusz; Sawosz, Ewa

2017-01-01

, while others have indicated that graphene might become health hazards. In this study, we explore the biocompatibility of graphene-related materials with chicken embryo red blood cells (RBC). The hemolysis assay was employed to evaluate the in vitro blood compatibility of reduced graphene, graphene oxide......, and reduced graphene oxide, because these materials have recently been used for biomedical applications, including injectable graphene-related particles. This study investigated structural damage, ROS production and hemolysis of chicken embryo red blood cells. Different forms of graphene, when incubated...... with chicken embryo RBC, were harmful to cell structure and induced hemolysis....

Hyperkalemia caused by rapid red cell transfusion and the potassium absorption filter

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Yasuhiko Imashuku

2017-01-01

Full Text Available We report a case of transient hyperkalemia during hysterectomy after cesarean section, due to preoperatively undiagnosed placenta accreta that caused unforeseen massive hemorrhage and required rapid red cell transfusion. Hyperkalemia-induced by rapid red cell transfusion is a well-known severe complication of transfusion; however, in patients with sudden massive hemorrhage, rapid red cell transfusion is necessary to save their life. In such cases, it is extremely important to monitor serum potassium levels. For an emergency situation, a system should be developed to ensure sufficient preparation for immediate transfusion and laboratory tests. Furthermore, sufficient stock of preparations to treat hyperkalemia, such as calcium preparations, diuretics, glucose, and insulin is required. Moreover, a transfusion filter that absorbs potassium has been developed and is now available for clinical use in Japan. The filter is easy to use and beneficial, and should be prepared when it is available.

Hyperkalemia caused by rapid red cell transfusion and the potassium absorption filter

Science.gov (United States)

Imashuku, Yasuhiko; Kitagawa, Hirotoshi; Mizuno, Takayoshi; Fukushima, Yutaka

2017-01-01

We report a case of transient hyperkalemia during hysterectomy after cesarean section, due to preoperatively undiagnosed placenta accreta that caused unforeseen massive hemorrhage and required rapid red cell transfusion. Hyperkalemia-induced by rapid red cell transfusion is a well-known severe complication of transfusion; however, in patients with sudden massive hemorrhage, rapid red cell transfusion is necessary to save their life. In such cases, it is extremely important to monitor serum potassium levels. For an emergency situation, a system should be developed to ensure sufficient preparation for immediate transfusion and laboratory tests. Furthermore, sufficient stock of preparations to treat hyperkalemia, such as calcium preparations, diuretics, glucose, and insulin is required. Moreover, a transfusion filter that absorbs potassium has been developed and is now available for clinical use in Japan. The filter is easy to use and beneficial, and should be prepared when it is available. PMID:28217070

Splenic red pulp macrophages are intrinsically superparamagnetic and contaminate magnetic cell isolates.

Science.gov (United States)

Franken, Lars; Klein, Marika; Spasova, Marina; Elsukova, Anna; Wiedwald, Ulf; Welz, Meike; Knolle, Percy; Farle, Michael; Limmer, Andreas; Kurts, Christian

2015-08-11

A main function of splenic red pulp macrophages is the degradation of damaged or aged erythrocytes. Here we show that these macrophages accumulate ferrimagnetic iron oxides that render them intrinsically superparamagnetic. Consequently, these cells routinely contaminate splenic cell isolates obtained with the use of MCS, a technique that has been widely used in immunological research for decades. These contaminations can profoundly alter experimental results. In mice deficient for the transcription factor SpiC, which lack red pulp macrophages, liver Kupffer cells take over the task of erythrocyte degradation and become superparamagnetic. We describe a simple additional magnetic separation step that avoids this problem and substantially improves purity of magnetic cell isolates from the spleen.

21 CFR 864.5300 - Red cell indices device.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Red cell indices device. 864.5300 Section 864.5300 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 § 864...

Red Blood Cell Storage Lesion

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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.

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

KAUST Repository

Deng, Peigang; Yin, Guangyao; Zhang, Tong Yi; Chang, Donald C.; Lee, Yi Kuen

2010-01-01

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

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

KAUST Repository

Deng, Peigang

2010-01-01

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

Relationship between red cell distribution width and early renal injury in patients with gestational diabetes mellitus.

Science.gov (United States)

Cheng, Dong; Zhao, Jiangtao; Jian, Liguo; Ding, Tongbin; Liu, Shichao

2016-09-01

Previous studies found that red cell distribution width was related to adverse cardiovascular events. However, few studies reported the relationship between red cell distribution width and early-stage renal injury in pregnant women with gestational diabetes mellitus. Using a cross-sectional design, 334 pregnant women with gestational diabetes mellitus were enrolled according to the criterion of inclusion and exclusion. Demographic and clinical examination data were collected. Depended on the urine albumin, study population were divided into case group (n = 118) and control group (n = 216). Compared with control group, the case group tend to be higher red cell distribution width level (13.6 ± 0.9 vs.12.5 ± 0.6, p gestational diabetes mellitus patients. The elevated red cell distribution width level might be a predictor of early-stage renal injury in pregnant women with gestational diabetes mellitus. As an easy and routine examination index, red cell distribution width may provide better clinical guidance when combined with other important indices.

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.

Evaluation of the effectiveness of packed red blood cell irradiation by a linear accelerator.

Science.gov (United States)

Olivo, Ricardo Aparecido; da Silva, Marcus Vinícius; Garcia, Fernanda Bernadelli; Soares, Sheila; Rodrigues Junior, Virmondes; Moraes-Souza, Helio

2015-01-01

Irradiation of blood components with ionizing radiation generated by a specific device is recommended to prevent transfusion-associated graft-versus-host disease. However, a linear accelerator can also be used in the absence of such a device, which is the case of the blood bank facility studied herein. In order to evaluate the quality of the irradiated packed red blood cells, this study aimed to determine whether the procedure currently employed in the facility is effective in inhibiting the proliferation of T lymphocytes without damaging blood components. The proliferation of T lymphocytes, plasma potassium levels, and the degree of hemolysis were evaluated and compared to blood bags that received no irradiation. Packed red blood cell bags were irradiated at a dose of 25Gy in a linear accelerator. For this purpose, a container was designed to hold the bags and to ensure even distribution of irradiation as evaluated by computed tomography and dose-volume histogram. Irradiation was observed to inhibit the proliferation of lymphocytes. The percentage of hemolysis in irradiated bags was slightly higher than in non-irradiated bags (p-value >0.05), but it was always less than 0.4% of the red cell mass. Although potassium increased in both groups, it was more pronounced in irradiated red blood cells, especially after seven days of storage, with a linear increase over storage time. The findings showed that, at an appropriate dosage and under validated conditions, the irradiation of packed red blood cells in a linear accelerator is effective, inhibiting lymphocyte proliferation but without compromising the viability of the red cells. Copyright © 2015 Associação Brasileira de Hematologia, Hemoterapia e Terapia Celular. Published by Elsevier Editora Ltda. All rights reserved.

Export of cyclic AMP by avian red cells and inhibition by prostaglandin A1

International Nuclear Information System (INIS)

Heasley, L.E.

1985-01-01

The mechanism by which PGA 1 inhibits cAMP export by avian red cells was studied, to provide details on the molecular mechanism of a prostaglandin action and on the process of cAMP export itself. The interaction of PGA 1 with pigeon red cells is a multi-step process of uptake, metabolism and secretion. [ 3 H]PGA rapidly enters red cells and is promptly metabolized (V/sub max/ ≥ 1 nmol/min/10 7 cells) to a compound (5) that remains in the aqueous layer after ethyl acetate extraction. Chromatographic analyses, amino acid content and fast atom bombardment mass spectrometry reveal that the polar metabolite is conjugated with glutathione (PGA 1 -GSH) at C-11 via a thioether bond and is largely (80%) reduced to the C-9 hydroxyl derivative

A case of red-cell adenosine deaminase overproduction associated with hereditary hemolytic anemia found in Japan.

Science.gov (United States)

Miwa, S; Fujii, H; Matsumoto, N; Nakatsuji, T; Oda, S; Asano, H; Asano, S

1978-01-01

A case of red cell adenosine deaminase (ADA) overproduction associated with hereditary hemolytic anemia is reported here. This appears to be the second report. Proband is a 38-year-old Japanese male who had hemoglobin, 15.8 g/100 ml; reticulocyte count, 4.5%; serum indirect bilirubin, 4.9 mg/100 ml; 51Cr-labeled red cell half-life, 12 days; red cells showed moderate stomatocytosis. His red cell ADA activity showed 40-fold increase while that of the mother showed 4-fold increase. The mother was hematologically normal. The father had a normal enzyme activity. The proband and the mother showed slightly high serum uric acid levels. The proband's red cell showed: ATP, 628 nmoles/ml (normal, 1,010--1,550); adenine nucleotide pool, 46% of the normal mean; 2,3-diphosphoglycerate content, 3,782 nmoles/ml (normal 4,170--5,300); increased oxygen affinity of hemoglobin, P50 of intact erythrocytes being 21.8 mmHg (normal, 24.1--26.1). Red cell glycolytic intermediates in the proband were low in general, and the rate of lactate production was low. Kinetic studies using crude hemolysate revealed a normal Km for adenosine, normal electrophoretic mobility but slightly abnormal pH curve and slightly low utilization of 2-deoxyadenosine. The ADA activity of lymphocytes was nearly normal.

51Chromium survival of Yt(a+) red cells as a determinant of the in vivo significance of anti-Yta

International Nuclear Information System (INIS)

Davey, R.J.; Simpkins, S.S.

1981-01-01

A case is presented in which anti-Yta produced a moderately accelerated removal of chromium-labeled Yt(a+) red blood cells (T1/2, 96 hours). Other reported examples of anti-Yta either have rapidly removed transfused Yt(a+) red blood cells or have permitted apparently normal survival of these cells. In light of this wide variation in in vivo potency of anti-Yta, it is recommended that chromium red blood cell survival studies be done before transfusion of Yt(a+) red blood cells in sensitized individuals

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.

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...

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 ...

Protective effects of red wine flavonols on 4-hydroxynonenal-induced apoptosis in PC12 cells.

Science.gov (United States)

Jang, Young Jin; Kang, Nam Joo; Lee, Ki Won; Lee, Hyong Joo

2009-08-01

There is accumulating evidence that a moderate consumption of red wine has health benefits, such as the inhibition of neurodegenerative diseases. Although this is generally attributed to resveratrol, the protective mechanisms and the active substance(s) remain unclear. We examined whether and how red wine extract (RWE) and red wine flavonols quercetin and myricetin inhibited 4-hydroxynonenal (HNE)-induced apoptosis of rat pheochromocytoma PC12 cells. RWE attenuated HNE-induced PC12 cell death in a dose-dependent manner. HNE induced cleavage of poly(ADP-ribose) polymerase, which is involved in DNA repair in the nucleus, and this was inhibited by RWE treatment. Treatment with RWE also inhibited HNE-induced nuclear condensation in PC12 cells. Data of 2',7'-dichlorofluorescin diacetate showed that RWE protected against apoptosis of PC12 cells by attenuating intracellular reactive oxygen species. The cytoprotective effects on HNE-induced cell death were stronger for quercetin and myricetin than for resveratrol. HNE-induced nuclear condensation was attenuated by quercetin and myricetin. These results suggest that the neuroprotective potential of red wine is attributable to flavonols rather than to resveratrol.

Nile Red Staining for Oil Determination in Microalgal Cells: A New Insight through Statistical Modelling

Directory of Open Access Journals (Sweden)

Ronald Halim

2015-01-01

Full Text Available In the wake of global warming and rapid fossil fuel depletion, microalgae emerge as promising feedstocks for sustainable biofuel production. Nile red staining acts as a rapid diagnostic tool to measure the amount of biodiesel-convertible lipid that the cells accumulate. There is a need for the development of a more uniform staining procedure. In its first phase, this study examined the dependence of microalgal Nile red fluorescence (Tetraselmis suecica in terms of its most pertinent staining variables. A quadratic surface model that successfully described the Nile red fluorescence intensity as a composite function of its variables was generated (r2=0.86. Cell concentration was shown to have a significant effect on the fluorescence intensity. Up to a certain threshold, fluorescence intensity was shown to increase with Nile red dye concentration. In its second phase, the study reviewed findings from previous Nile red studies to elucidate some of the fundamental mechanism underlying the diffusion of Nile red dye molecules into the microalgal cells and their subsequent interaction with intracellular lipids. Through the review process, we were able to develop a simple framework that provided a set of guidelines for the standardization of the Nile red staining procedure across different microalgal species.

Inborn defects in the antioxidant systems of human red blood cells

NARCIS (Netherlands)

van Zwieten, Rob; Verhoeven, Arthur J.; Roos, Dirk

2014-01-01

Red blood cells (RBCs) contain large amounts of iron and operate in highly oxygenated tissues. As a result, these cells encounter a continuous oxidative stress. Protective mechanisms against oxidation include prevention of formation of reactive oxygen species (ROS), scavenging of various forms of

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 ...

Simulation study of InGaN intermediate-band solar cells

International Nuclear Information System (INIS)

Chen, Kuo-Feng; Hung, Chien-Lun; Tsai, Yao-Lung

2016-01-01

The performances of single-junction InGaN solar cells with various intermediate bands (IBs) have been simulated using the lifetime model of a 1D simulation program called Analysis of Microelectronic and Photonic Structures (AMPS-1D). It has been observed that the maximum efficiencies of the InGaN solar cells with one, two and three intermediate bands are 47.72%, 55.10% and 58.20%, respectively, which outperform the 25.96% efficiency of the conventional single-junction structure by far. This is primarily attributed to the outstanding capability of the light harvesting from the sub-bandgap absorption. At the optimized bandgap of 2.41 eV, two-IB InGaN solar cells with the IB positions located at 0.95–1.1 eV and 0.3–0.75 eV, respectively, may have an opportunity to realize over 50% efficiency. (paper)

Restrictive or Liberal Red-Cell Transfusion for Cardiac Surgery

DEFF Research Database (Denmark)

Mazer, C David; Whitlock, Richard P; Fergusson, Dean A

2017-01-01

BACKGROUND: The effect of a restrictive versus liberal red-cell transfusion strategy on clinical outcomes in patients undergoing cardiac surgery remains unclear. METHODS: In this multicenter, open-label, noninferiority trial, we randomly assigned 5243 adults undergoing cardiac surgery who had a E...

Morphological changes of the red blood cells treated with metal oxide nanoparticles.

Science.gov (United States)

Kozelskaya, A I; Panin, A V; Khlusov, I A; Mokrushnikov, P V; Zaitsev, B N; Kuzmenko, D I; Vasyukov, G Yu

2016-12-01

The toxic effect of Al 2 O 3 , SiО 2 and ZrО 2 nanoparticles on red blood cells of Wistar rats was studied in vitro using the atomic force microscopy and the fluorescence analysis. Transformation of discocytes into echinocytes and spherocytes caused by the metal oxide nanoparticles was revealed. It was shown that only extremely high concentration of the nanoparticles (2mg/ml) allows correct estimating of their effect on the cell morphology. Besides, it was found out that the microviscosity changes of red blood cell membranes treated with nanoparticles began long before morphological modifications of the cells. On the contrary, the negatively charged ZrO 2 and SiO 2 nanoparticles did not affect ghost microviscosity up to concentrations of 1μg/ml and 0.1mg/ml, correspondingly. In its turn, the positively charged Al 2 O 3 nanoparticles induced structural changes in the lipid bilayer of the red blood cells already at a concentration of 0.05μg/ml. A decrease in microviscosity of the erythrocyte ghosts treated with Al 2 O 3 and SiO 2 nanoparticles was shown. It was detected that the interaction of ZrO 2 nanoparticles with the cells led to an increase in the membrane microviscosity and cracking of swollen erythrocytes. Copyright © 2016 Elsevier B.V. All rights reserved.

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.

Sphero-echinocytosis of human red blood cells caused by snake, red-back spider, bee and blue-ringed octopus venoms and its inhibition by snake sera.

Science.gov (United States)

Flachsenberger, W; Leigh, C M; Mirtschin, P J

1995-06-01

It was found that bee (Apis mellifera) venom, red-back spider (Latrodectus mactans) venom, blue-ringed octopus (Hapalochlaena maculosa) venom, ten different snake venoms, phospholipase A2 and four snake toxins caused sphero-echinocytosis of human red blood cells at 200 ng/ml. Most venoms and toxins lost the ability to deform human red blood cells when their components of less than mol. wt 10,000 were applied. In a number of cases the sphero-echinocytotic effect was also inhibited by blood sera of Notechis scutatus and Pseudonaja textilis.

Two-Dimensional Computational Flow Analysis and Frictional Characteristics Model for Red Blood Cell under Inclined Centrifuge Microscopy

Science.gov (United States)

Funamoto, Kenichi; Hayase, Toshiyuki; Shirai, Atsushi

Simplified two-dimensional flow analysis is performed in order to simulate frictional characteristics measurement of red blood cells moving on a glass plate in a medium with an inclined centrifuge microscope. Computation under various conditions reveals the influences of parameters on lift, drag, and moment acting on a red blood cell. Among these forces, lift appears only when the cell is longitudinally asymmetric. By considering the balance of forces, the frictional characteristics of the red blood cell are modeled as the sum of Coulomb friction and viscous drag. The model describes the possibility that the red blood cell deforms to expand in the front side in response to the inclined centrifugal force. When velocity exceeds some critical value, the lift overcomes the normal centrifugal force component, and the thickness of the plasma layer between the cell and the glass plate increases from the initial value of the plasma protein thickness.

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.

Low-level red laser therapy alters effects of ultraviolet C radiation on Escherichia coli cells

International Nuclear Information System (INIS)

Canuto, K.S.; Guimaraes, O.R.; Geller, M.; Sergio, L.P.S.; Paoli, F.; Fonseca, A.S.

2015-01-01

Low-level lasers are used at low power densities and doses according to clinical protocols supplied with laser devices or based on professional practice. Although use of these lasers is increasing in many countries, the molecular mechanisms involved in effects of low-level lasers, mainly on DNA, are controversial. In this study, we evaluated the effects of low-level red lasers on survival, filamentation, and morphology of Escherichia coli cells that were exposed to ultraviolet C (UVC) radiation. Exponential and stationary wild-type and uvrA-deficient E. coli cells were exposed to a low-level red laser and in sequence to UVC radiation. Bacterial survival was evaluated to determine the laser protection factor (ratio between the number of viable cells after exposure to the red laser and UVC and the number of viable cells after exposure to UVC). Bacterial filaments were counted to obtain the percentage of filamentation. Area-perimeter ratios were calculated for evaluation of cellular morphology. Experiments were carried out in duplicate and the results are reported as the means of three independent assays. Pre-exposure to a red laser protected wild-type and uvrA-deficient E. coli cells against the lethal effect of UVC radiation, and increased the percentage of filamentation and the area-perimeter ratio, depending on UVC fluence and physiological conditions in the cells. Therapeutic, low-level red laser radiation can induce DNA lesions at a sub-lethal level. Consequences to cells and tissues should be considered when clinical protocols based on this laser are carried out. (author)

Low-level red laser therapy alters effects of ultraviolet C radiation on Escherichia coli cells

Energy Technology Data Exchange (ETDEWEB)

Canuto, K.S.; Guimaraes, O.R.; Geller, M. [Centro Universitario Serra dos Orgaos, Teresopolis, RJ (Brazil). Centro de Ciencias da Saude; Sergio, L.P.S. [Instituto de Biologia Roberto Alcantara Gomes, Rio de Janeiro, RJ (Brazil). Departamento de Biofisica e Biometria; Paoli, F. [Universidade Federal de Juiz de Fora (UFJF), Juiz de Fora, MG (Brazil). Departamento de Morfologia; Fonseca, A.S., E-mail: adnfonseca@ig.com.br [Universidade Federal do Estado do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ (Brazil). Departamento de Ciencias Fisiologicas

2015-10-15

Low-level lasers are used at low power densities and doses according to clinical protocols supplied with laser devices or based on professional practice. Although use of these lasers is increasing in many countries, the molecular mechanisms involved in effects of low-level lasers, mainly on DNA, are controversial. In this study, we evaluated the effects of low-level red lasers on survival, filamentation, and morphology of Escherichia coli cells that were exposed to ultraviolet C (UVC) radiation. Exponential and stationary wild-type and uvrA-deficient E. coli cells were exposed to a low-level red laser and in sequence to UVC radiation. Bacterial survival was evaluated to determine the laser protection factor (ratio between the number of viable cells after exposure to the red laser and UVC and the number of viable cells after exposure to UVC). Bacterial filaments were counted to obtain the percentage of filamentation. Area-perimeter ratios were calculated for evaluation of cellular morphology. Experiments were carried out in duplicate and the results are reported as the means of three independent assays. Pre-exposure to a red laser protected wild-type and uvrA-deficient E. coli cells against the lethal effect of UVC radiation, and increased the percentage of filamentation and the area-perimeter ratio, depending on UVC fluence and physiological conditions in the cells. Therapeutic, low-level red laser radiation can induce DNA lesions at a sub-lethal level. Consequences to cells and tissues should be considered when clinical protocols based on this laser are carried out. (author)

Band tailing and efficiency limitation in kesterite solar cells

Science.gov (United States)

Gokmen, Tayfun; Gunawan, Oki; Todorov, Teodor K.; Mitzi, David B.

2013-09-01

We demonstrate that a fundamental performance bottleneck for hydrazine processed kesterite Cu2ZnSn(S,Se)4 (CZTSSe) solar cells with efficiencies reaching above 11% can be the formation of band-edge tail states, which quantum efficiency and photoluminescence data indicate is roughly twice as severe as in higher-performing Cu(In,Ga)(S,Se)2 devices. Low temperature time-resolved photoluminescence data suggest that the enhanced tailing arises primarily from electrostatic potential fluctuations induced by strong compensation and facilitated by a lower CZTSSe dielectric constant. We discuss the implications of the band tails for the voltage deficit in these devices.

A modified method for the in vivo labeling of red blood cells with /sup 99m/Tc: concise communication

International Nuclear Information System (INIS)

Callahan, R.J.; Froelich, J.W.; McKusick, K.A.; Leppo, J.; Strauss, H.W.

1982-01-01

The rate of incorporation of /sup 99m/Tc into red blood cells pretinned in vivo was measured by collecting blood samples in stannous DTPA solution, which served as a competing ligand for /sup 99m/Tc. This collection technique permitted a measurement of high-affinity red-cell labeling efficiency at the instant of sampling. At 0.5 min after injection only 62% of technetium is tightly bound to the red cell; this rises to 94.5% at 10 min. Based on the graded labeling of the red cells, the in vivo labeling procedure was modified by isolating pertechnetate and red blood cells tinned in vivo in a syringe during the first 10 min of labeling. The pertechnetate is thus prevented from distributing to extravascular compartments, and 90% of the injected /sup 99m/Tc is firmly bound to red blood cells at the time of injection. In a series of 23 patients, seven were tested with the in vivo method and seven with the modified in vivo method, and nine patients were tested with each method on separate occasions. A decrease in gastric activity and improved image quality were found with the modified method compared with the standard method of in vivo red-cell labeling

Modeling of SAR returns from a red pine stand

Science.gov (United States)

Lang, R. H.; Kilic, O.; Chauhan, N. S.; Ranson, J.

1992-01-01

Bright P-band radar returns from red pine forests have been observed on synthetic aperture radar (SAR) images in Bangor, Maine. A plot of red pine trees was selected for the characterization and modeling to understand the cause of the high P-band returns. The red pine stand under study consisted of mature trees. Diameter at breast height (DBH) measurements were made to determine stand density as a function of tree diameter. Soil moisture and bulk density measurements were taken along with ground rough surface profiles. Detailed biomass measurements of the needles, shoots, branches, and trunks were also taken. These site statistics have been used in a distorted Born approximation model of the forest. Computations indicate that the direct-reflected or the double-bounce contributions from the ground are responsible for the high observed P-band returns for HH polarization.

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

Science.gov (United States)

Ghadage, Vijay H.; Kulkarni, Gauri R.

2011-03-01

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

Erythropoetin treatment can increase 2,3-diphosphoglycerate levels in red blood cells.

Science.gov (United States)

Birgegård, G; Sandhagen, B

2001-01-01

Some patients experience an improved well-being during treatment with recombinant human erythropoietin even with an unchanged Hb level. We have hypothesized that this may not be only a placebo effect. 2,3-diphosphoglycerate (2,3-DPG) in red blood cells increases in response to anaemia/hypoxia and causes a shift of the oxygen dissociation curve, allowing a more effective oxygen delivery. We have investigated red cell 2,3-DPG concentrations during erythropoietin treatment in healthy volunteers as a mediator of a possible physiological explanation. Thirteen healthy subjects with no iron deficiency were recruited and randomly assigned to a treatment group comprising five males and three females and a control group including three males and two females. The treatment group was treated with erythropoietin (Recormon), 20 IE/kg subcutaneously three times/week for 4 weeks. Blood samples were collected at each injection day and 10 days after the last injection and at corresponding times in the control group. B-Hb, red cell 2,3-DPG and P50 were measured by standard techniques and oxygen-releasing capacity was calculated. due to the sampling (26 ml each time, three times/week) the mean Hb level was lowered from 140.5 +/- 5.9 to 128.6 +/- 10.4 g/L in the control group whereas the erythropoietin treatment group maintained a mean Hb level of about 142 g/L (plevel curve as well as that for oxygen releasing capacity also differed significantly between the two groups (p levels. treatment with erythropoietin causes an increase in red cell 2,3-DPG levels.

Blue and red emission in wide band gap BaZrO{sub 3}:Yb{sup 3+},Tm{sup 3+}

Energy Technology Data Exchange (ETDEWEB)

Borja-Urby, R. [Centro de Investigaciones en Optica, A. C., C. P. 37150 Leon, Gto. (Mexico); Diaz-Torres, L.A., E-mail: ditlacio@cio.mx [Centro de Investigaciones en Optica, A. C., C. P. 37150 Leon, Gto. (Mexico); Salas, P. [Centro de Fisica Aplicada y Tecnologia Avanzada, Universidad Nacional Autonoma de Mexico, A. P. 1-1010, Queretaro 76000 (Mexico); Vega-Gonzalez, M. [Centro de Geociencias-Universidad Nacional Autonoma de Mexico, A. P. 1-1010, Queretaro 76000 (Mexico); Angeles-Chavez, C. [Instituto Mexicano del Petroleo, Programa de Ingenieria Molecular, Cd. Mexico D.F. 07730 (Mexico)

2010-10-25

Under NIR excitation at 967 intense blue and red photoluminescence (PL) emissions are observed at room temperature in codoped Tm{sup 3+}-Yb{sup 3+} barium zirconate (BaZrO{sub 3}:Yb,Tm) powders. Powders were prepared by a simple hydrothermal method, and present a wide band gap that depends on the total rare earth content due to the degree of disorder induced in the BaZrO{sub 3} lattice by the substitution of the rare earth ions. Rietveld refinements of the XRD patterns indicated the presence of primary nanocrystallites with sizes between 50 and 70 nm depending on the Tm{sup 3+} content. Scanning transmission electron microscopy (STEM) shows that these primary particles self-aggregated in larger secondary particles which present a regular morphology with sizes around 1 {mu}m. The intense blue and red PL emissions in BaZrO{sub 3} powders under 967 nm excitation are governed by energy transfer processes from Yb{sup 3+} ions to Tm{sup 3+} ions and crossrelaxation among Tm{sup 3+} ions.

A Gaussian process and derivative spectral-based algorithm for red blood cell segmentation

Science.gov (United States)

Xue, Yingying; Wang, Jianbiao; Zhou, Mei; Hou, Xiyue; Li, Qingli; Liu, Hongying; Wang, Yiting

2017-07-01

As an imaging technology used in remote sensing, hyperspectral imaging can provide more information than traditional optical imaging of blood cells. In this paper, an AOTF based microscopic hyperspectral imaging system is used to capture hyperspectral images of blood cells. In order to achieve the segmentation of red blood cells, Gaussian process using squared exponential kernel function is applied first after the data preprocessing to make the preliminary segmentation. The derivative spectrum with spectral angle mapping algorithm is then applied to the original image to segment the boundary of cells, and using the boundary to cut out cells obtained from the Gaussian process to separated adjacent cells. Then the morphological processing method including closing, erosion and dilation is applied so as to keep adjacent cells apart, and by applying median filtering to remove noise points and filling holes inside the cell, the final segmentation result can be obtained. The experimental results show that this method appears better segmentation effect on human red blood cells.

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

Energy Technology Data Exchange (ETDEWEB)

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

2008-07-07

Recently, we derived equations relating the flow of adult red blood cells through a placental arterio-venous anastomosis with intra-uterine and post-natal measured adult hemoglobin concentrations. In this letter, we re-derived the equations, now including a more realistic nonlinear decay of adult red blood cells, and re-evaluated the measurement accuracy of the arterio-venous flow and the lifetime of the red blood cells. (letter to the editor)

Cell fusion phenomena detected after in utero transplantation of Ds-red-harboring porcine amniotic fluid stem cells into EGFP transgenic mice.

Science.gov (United States)

Peng, Shao-Yu; Chen, Yu-Hsu; Chou, Chih-Jen; Wang, Yao-Horng; Lee, Hung-Maan; Cheng, Winston Teng-Kui; Shaw, S W Steven; Wu, Shinn-Chih

2014-05-01

Amniotic fluid stem cells (AFSCs) are derived from the amniotic fluid of the developing fetus and can give rise to diverse differentiated cells of ectoderm, mesoderm, and endoderm lineages. Intrauterine transplantation is an approach used to cure inherited genetic fetal defects during the gestation period of pregnant dams. Certain disease such as osteogenesis imperfecta was successfully treated in affected fetal mice using this method. However, the donor cell destiny remains uncertain. The purpose of this study was to investigate the biodistribution and cell fate of Ds-red-harboring porcine AFSCs (Ds-red pAFSCs) after intrauterine transplantation into enhanced green fluorescent protein-harboring fetuses of pregnant mice. Pregnant mice (12.5 days) underwent open laparotomy with intrauterine pAFSC transplantation (5 × 10(4) cells per pup) into fetal peritoneal cavity. Three weeks after birth, the mice were sacrificed. Several samples from different organs were obtained for histological examination and flow cytometric analysis. Ds-red pAFSCs migrated most frequently into the intestines. Furthermore, enhanced green fluorescent protein and red fluorescent protein signals were co-expressed in the intestine and liver cells via immunohistochemistry studies. In utero xenotransplantation of pAFSCs fused with recipient intestinal cells instead of differentiating or maintaining the undifferentiated status in the tissue. © 2014 John Wiley & Sons, Ltd.

Brazilian red propolis: phytochemical screening, antioxidant activity and effect against cancer cells.

Science.gov (United States)

de Mendonça, Izabel Cristina Gomes; Porto, Isabel Cristina Celerino de Moraes; do Nascimento, Ticiano Gomes; de Souza, Naiana Soares; Oliveira, José Marcos dos Santos; Arruda, Rodolfo Elleson dos Santos; Mousinho, Kristiana Cerqueira; dos Santos, Aldenir Feitosa; Basílio-Júnior, Irinaldo Diniz; Parolia, Abhishek; Barreto, Francisco Stefânio

2015-10-14

The implementation of new public healthcare models that stimulate the use of natural products from traditional medicine, as a so-called integrated medicine, refers to an approach that use best of both conventional medicine and traditional medicine. Propolis is a widely used natural product by different ancient cultures and known to exhibit biological activities beneficial for health. The large number of studies conducted with propolis had shown that its chemical composition differs as a function of the climate, plant diversity and bee species and plays an important role on its therapeutic properties. The aim of this study was to analyse the phytochemical profile of the ethanolic extract of red propolis (EEP) and its fractionation, antioxidant action of EEP and its fractions hexane, cloroform and ethyl acetate and cytotoxic activity of EEP on human tumour cell lines SF-295 (glioblastoma), OVCAR-8 (ovary) and HCT-116 (colon). EEP was obtained by maceration with absolute ethanol, then it was concentrated in rotaevaporator up to complete evaporation of the solvent. The crude extract was fractionated with hexane, ethyl acetate, chloroform and methanol and they were subjected to phytochemical screening and total phenolic compounds. Antioxidant activity of EEP and fractions was done by means of the 2,2-diphenyl-1-picryhydrazyl (DPPH) method. Biomarkers of red propolis were identified by LC-Orbitrap-FTMS. To assess cytotoxic activity of the extract, cells were exposed to EEP over 72 h. Cell viability was assessed by means of MTT assay. The percentage of cell growth inhibition (IC50) was analysed by means of non-linear regression, and the absorbance values of the various investigated concentrations were subjected to one-factor analysis of variance (ANOVA) followed by Tukey's or Tamhane's tests (α = 0.05). The results obtained using phytochemical screening and LC-Orbitrap-FTMS indicated the presence of phlobaphene tannins, catechins, chalcones, aurones, flavonones

effect of thermal stress of short duration on the red blood cell

African Journals Online (AJOL)

Dr Ivanc

2013-05-01

May 1, 2013 ... of red blood cell count (RBC), haemoglobin concentration, packed cell volume ... The temperature at which stress begins to occur ..... of Barton (2002) that PCV is a measure of the cellular ..... Tufts B (eds) Fish respiration.

The intensity of the 1602 cm-1 band in human cells is related to mitochondrial activity

NARCIS (Netherlands)

Pully, V.V.; Otto, Cornelis

2009-01-01

We report a Raman band at 1602 cm−1 in the spectra of human cells, which previously had only been observed in mitochondria of yeast cells. This band, which has not yet been assigned to a particular molecular species, was found to occur in HeLa cells, peripheral blood lymphocytes, human mesenchymal

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

DEFF Research Database (Denmark)

Dyrda, Agnieszka; Cytlak, Urszula; Ciuraszkiewicz, Anna

2010-01-01

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

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.

Reduction in unnecessary red blood cell folate testing by restricting computerized physician order entry in the electronic health record.

Science.gov (United States)

MacMillan, Thomas E; Gudgeon, Patrick; Yip, Paul M; Cavalcanti, Rodrigo B

2018-05-02

Red blood cell folate is a laboratory test with limited clinical utility. Previous attempts to reduce physician ordering of unnecessary laboratory tests, including folate, have resulted in only modest success. The objective of this study was to assess the effectiveness and impacts of restricting red blood cell folate ordering in the electronic health record. This was a retrospective observational study from January 2010 to December 2016 at a large academic healthcare network in Toronto, Canada. All inpatients and outpatients who underwent at least 1 red blood cell folate or vitamin B12 test during the study period were included. Red blood cell folate ordering was restricted to clincians in gastroenterology and hematology and was removed from other physicians' computerized order entry screen in the electronic health record in June 2013. Red blood cell folate testing decreased by 94.4% during the study, from a mean of 493.0 (SD 48.0) tests/month before intervention to 27.6 (SD 10.3) tests/month after intervention (P<.001). Restricting red blood cell folate ordering in the electronic health record resulted in a large and sustained reduction in red blood cell folate testing. Significant cost savings estimated at over a quarter-million dollars (CAD) over three years were achieved. There was no significant clinical impact of the intervention on the diagnosis of folate deficiency. Copyright © 2018. Published by Elsevier Inc.

Cholestasis in neonates with red cell alloimmune hemolytic disease: incidence, risk factors and outcome.

Science.gov (United States)

Smits-Wintjens, Vivianne E H J; Rath, Mirjam E A; Lindenburg, Irene T M; Oepkes, Dick; van Zwet, Erik W; Walther, Frans J; Lopriore, Enrico

2012-01-01

Etiology of cholestatic liver disease in neonates with hemolytic disease of the newborn (HDN) has been associated with iron overload due to intrauterine red cell transfusions (IUTs). Data on the incidence and severity of cholestasis in neonates with HDN are scarce, and little is known about pathogenesis, risk factors, neonatal management and outcome. To evaluate incidence, risk factors, management and outcome of cholestasis in neonates with red cell alloimmune hemolytic disease. All (near-) term neonates with HDN due to red cell alloimmunization admitted to our center between January 2000 and July 2010 were included in this observational study. Liver function tests (including conjugated bilirubin) were routinely performed in the neonatal period. We recorded the presence of cholestasis, investigated several potential risk factors and evaluated the management and outcome in affected neonates. A total of 313 infants with red cell alloimmune hemolytic disease treated with or without IUTs were included. The incidence of cholestasis was 13% (41/313). Two risk factors were independently associated with cholestasis: treatment with at least one IUT (OR 5.81, 95% CI 1.70-19.80, p = 0.005) and rhesus D type of alloimmunization (OR 4.66, 95% CI 1.05-20.57, p = 0.042). Additional diagnostic tests to investigate possible causes of cholestasis were all negative. In 5 infants (12%), supportive medical and nutritional therapy was started, and one neonate required iron chelation therapy. Cholestasis occurs in 13% of neonates with HDN due to red cell alloimmunization, and it is independently associated with IUT treatment and rhesus D type of alloimmunization. Copyright © 2012 S. Karger AG, Basel.

Laser ektacytometry and evaluation of statistical characteristics of inhomogeneous ensembles of red blood cells

Science.gov (United States)

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

2014-10-01

The paper is devoted to development of the laser ektacytometry technique for evaluation of the statistical characteristics of inhomogeneous ensembles of red blood cells (RBCs). We have analyzed theoretically laser beam scattering by the inhomogeneous ensembles of elliptical discs, modeling red blood cells in the ektacytometer. The analysis shows that the laser ektacytometry technique allows for quantitative evaluation of such population characteristics of RBCs as the cells mean shape, the cells deformability variance and asymmetry of the cells distribution in the deformability. Moreover, we show that the deformability distribution itself can be retrieved by solving a specific Fredholm integral equation of the first kind. At this stage we do not take into account the scatter in the RBC sizes.

Test of Neural Network Techniques using Simulated Dual-Band Data of LEO Satellites

Science.gov (United States)

2010-09-01

component to allow for glinting surfaces, such as solar panels. Radiant intensities are calculated for a blue band (468-495 nm) and a red band (738-765...When a satellite is visible for at least one of the observation sites, OSC is used to calculate radiant intensity in the blue and red spectral bands...Input node, aji , contains the ith value of radiant intensity for the jth pass of a satellite. In this work, the n input nodes are values of radiant

The effect of prefreeze rejuvenation on postthaw storage of red blood cells in AS-3 and SAGM.

Science.gov (United States)

Lelkens, Charles C M; Lagerberg, Johan W M; de Korte, Dirk

2017-06-01

We investigated whether improving the metabolic status of red blood cell concentrates before freezing could extend the postthaw shelf life beyond 14 days while still meeting the requirements for hemolysis (0.8%) and total adenylate (>82% of original values). At Day 8 after collection, four leukoreduced red blood cell concentrates in saline-adenine-glucose-mannitol (SAGM) were pooled, mixed, and split (n = 4). Of these concentrates, two were rejuvenated in Rejuvesol. In addition, two leukoreduced red blood cell concentrates in phosphate-adenine-glucose-guanosine-gluconate-mannitol (PAGGGM) were pooled, mixed, and split at Day 8 after collection (n = 4). All concentrates were glycerolized, frozen, and stored for at least 2 weeks at -80°C. After thawing and deglycerolization, from each pair, one red blood cell concentrate was resuspended in SAGM, and one was suspended in AS-3. During postthaw storage at 2 to 6°C for 35 days, all concentrates were sampled weekly and analyzed for hematologic, metabolic, and morphologic parameters. Both Rejuvesol and PAGGGM treatment produced increased adenosine triphosphate and total adenylate and 2,3-diphosphoglycerate levels compared with untreated red blood cell concentrates. Regardless of prefreeze Rejuvesol or PAGGGM treatment, postthaw hemolysis remained below 0.8% during 7 days in SAGM and during 35 days in AS-3. At Day 35 of postthaw storage in AS-3, total adenylate in nonrejuvenated red blood cell concentrates had decreased to 72% of the original values; whereas, in prefreeze Rejuvesol-treated and PAGGGM-treated concentrates, adenylate values were still were at 101% and 98%, respectively. Based on maximum allowable hemolysis of 0.8% and total adenylate content greater than 82% of the original value, thawed, prefreeze Rejuvesol-treated or PAGGGM-treated red blood cell concentrates can be stored for 35 days at 2 to 6ºC in AS-3. © 2017 AABB.

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

Alterations in plasma phosphorus, red cell 2,3-diphosphoglycerate and P50 following open heart surgery.

Science.gov (United States)

Hasan, R A; Sarnaik, A P; Meert, K L; Dabbagh, S; Simpson, P; Makimi, M

1994-12-01

To evaluate changes in and the correlation between plasma phosphorus, red cell 2,3-diphosphoglycerate (DPG) and adenosine triphosphate (ATP), and P50 in children following heart surgery. Prospective, observational study with factorial design. A pediatric intensive care unit in a university hospital. Twenty children undergoing open heart surgery for congenital heart defects. None. Red cell 2,3-DPG and ATP, P50, plasma phosphorus, and arterial lactate were obtained before and at 1, 8, 16, 24, 48, and 72 hours after surgery. The amount of intravenous fluid and glucose administered, and age of blood utilized were documented. Variables were analyzed by repeated measure analysis of variance followed by paired t-tests. To investigate the relationship between variables at each time point, scatterplot matrices and correlation coefficients were obtained. There was a reduction in plasma phosphorus, red cell 2,3-DPG, and P50 and an increase in arterial lactate at 1, 8, 16, 24, 48, and 72 hours after surgery. Red cell 2,3-DPG correlated with P50 at 1, 8 and 16 hours. The decrease in the plasma phosphorus correlated with the amounts of intravenous fluid and glucose administered on the day of surgery and on the first and second postoperative days. The age of the blood utilized correlated with the decrease in red cell 2,3-DPG on the day of surgery. Reduction in red cell 2,3-DPG, P50, and plasma phosphorus occurs after open heart surgery in children. These changes can potentially contribute to impaired oxygen utilization in the postoperative period, when adequacy of tissue oxygenation is critical.

Detection of pulmonary hemorrhage with technetium-labeled red cells

International Nuclear Information System (INIS)

Winzelberg, G.G.; Laman, D.; Sachs, M.; Miller, W.H.

1981-01-01

Noninvasive techniques to aid in the diagnosis of massive pulmonary hemoptysis would be helpful in guiding more-invasive procedures such as bronchial artery angiography, which carries a risk of transverse myelitis. A patient was studied with technetium-labeled red cells and successfully detected a site of intermittent hemorrhage from the lung

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

Electromagnetic shielding behavior of polyaniline using Red Mud (industrial waste) as filler in the X – band (8.2–12.4 GHz) frequency range

Energy Technology Data Exchange (ETDEWEB)

Pande, Anu; Gairola, Preeti [Uttaranchal University, Prem Nagar, Dehradun (India); Sambyal, Pradeep [National Physical Laboratory (CSIR), K, S. Krishnan Marg, New Delhi (India); Gairola, S.P., E-mail: spgairola10@gmail.com [Uttaranchal University, Prem Nagar, Dehradun (India); Kumar, Vinod [Centre for Energy Studies, Indian Institute of Technology, New Delhi (India); Singh, Kuldeep [Central Electrochemical Research Institute (CSIR), Karaikudi, Tamilnadu (India); Dhawan, S.K. [National Physical Laboratory (CSIR), K, S. Krishnan Marg, New Delhi (India)

2017-03-01

In today’s times where pollution of all kinds is at its peak, numerous efforts are being made to find proper waste disposal methods. Moving on the same lines, this paper presents an economical and environmentally safe method of disposal of red mud to control electromagnetic pollution by using it as an electromagnetic shielding material. Composites of PANI/RM have been prepared by in-situ chemical oxidative polymerization and have been tested for structural analysis, thermal stability and magnetization by XRD, TGA and VSM techniques respectively. Further, the composites have shown shielding effectiveness of 33–41 dB (>99.99% attenuation) in 8.2–12.4 GHz frequency range (X-band) at a thickness of 3 mm which is absorption dominated. Thus, the results conclude that the incorporation of red mud into polymer matrix can serve two purposes – firstly, it can provide a good alternative as a shielding material and secondly, it can prove to be a feasible way of waste disposal. - Highlights: • An attempt to find out application of red mud in controlling electromagnetic pollution. • Waste utilization for technology: Red mud is an insoluble industrial waste used for EMI Shielding application. • Using and testing of Red Mud as filler instead of the other widely used fillers. • Characterization of materials (Red Mud/Polyaniline composite) for EMI shielding Application. • EMI Shielding results discussions of new material (Red Mud/Polyaniline).

Low Band Gap Polymers for Roll-to-Roll Coated Polymer Solar Cells

DEFF Research Database (Denmark)

Bundgaard, Eva; Hagemann, Ole; Manceau, Matthieu

2010-01-01

connected cells were prepared with a total module active area of 96 cm2. The devices were tested for operational stability under simulated sunlight (AM1.5G) and natural sunlight, and the photochemical stability of the polymer was examined using a combination of UV−vis and IR spectroscopy.......We present the synthesis of a low band gap copolymer based on dithienothiophene and dialkoxybenzothiadiazole (poly(dithienothiophene-co-dialkoxybenzothiadiazole), PDTTDABT). The optical properties of the polymer showed a band gap of 1.6 eV and a sky-blue color in solid films. The polymer...... around a 1:2 mixing ratio. Roll-to-roll coated polymer solar cell devices were prepared under ambient conditions employing solution processing in all steps including the metallic back electrode that was printed as a grid giving semitransparent solar cell devices. Solar cell modules comprising 16 serially...

Hereditary stomatocytosis: association of low 2,3-diphosphoglycerate with increased cation pumping by the red cell.

Science.gov (United States)

Wiley, J S; Cooper, R A; Adachi, K; Asakura, T

1979-01-01

The levels of glycolytic intermediates have been measured in red cells from patients with both overhydrated and dehydrated varieties of the hereditary stomatocytosis syndrome. Red cell 2,3-diphosphoglycerate was reduced by 33% below normal in all patients with either stomatocyte or target cell morphologies (i.e. over or under hydrated varieties respectively). The relative decrement in 2,3-diphosphoglycerate was even greater when abnormal cells were compared with control cells with similar reticulocytosis. Red cell ADP concentrations in stomatocytosis were significantly increased above normal but ATP concentrations were not significantly changed. Whole blood oxygen affinity in stomatocytosis was increased in proportion to the lowered content of diphosphoglycerate. Some new parameters of membrane transport in hereditary stomatocytosis have been measured. Platelet K+ and Na+ concentrations and platelet K+ permeability were normal in stomatocytosis. The number of 3H-uridine transport sites in stomatocytes were increased by 9-39% above normal and this increment was the same as the increment in red cell lipids (0-38%). Hereditary stomatocytes contain 2-10-fold more cation pumps than normal and the increased active cation pumping may explain the high ADP, the low 2,3-diphosphoglycerate concentration and the increased oxygen affinity in this syndrome.

The air we breathe: three vital respiratory gases and the red blood cell: oxygen, nitric oxide, and carbon dioxide.

Science.gov (United States)

Dzik, Walter H

2011-04-01

Three vital respiratory gases-oxygen (O(2)), nitric oxide (NO), and carbon dioxide (CO(2))-intersect at the level of the human red blood cell (RBC). In addition to hemoglobin (Hb)'s central role in O(2) transport, interaction of Hb with the Band 3 metabolon balances RBC energy flow. 2,3-Diphosphoglycerate enhances O(2) transport across the placenta and plays an important role in regulating RBC plasticity. NO is a key mediator of hypoxic vasodilation, but the precise role of RBC Hb remains controversial. In addition to established theories that depend on RBC uptake, delivery, and discharge of NO or its metabolites, an alternative hypothesis based on RBC permeability is suggested. NO depletion by free Hb may account for several clinical features seen during intravascular hemolysis or during deliberate infusion of Hb solutions used as RBC substitutes. CO(2) released by tissues triggers oxygen release through a series of well-coordinated reactions centered on the Band 3 metabolon. While RBC carbonic anhydrase and the Band 3 anion exchanger are central to this process, there is surprisingly little research on the kinetics of CO(2) clearance by transfusion. The three RBC gases are directly related to the three principal gases of Earth's atmosphere. Human fossil fuel consumption dumps 90 million metric tons of carbon into the atmosphere annually. Increasing CO(2) levels are linked to global warming, melting Arctic ice, rising sea levels, and climate instability. Just as individual cells depend on balance of the three vital gases, so too will their balance determine survival of life on Earth. © 2011 American Association of Blood Banks.

Importance of methodological standardization for the ektacytometric measures of red blood cell deformability in sickle cell anemia

NARCIS (Netherlands)

Renoux, Céline; Parrow, Nermi; Faes, Camille; Joly, Philippe; Hardeman, Max; Tisdale, John; Levine, Mark; Garnier, Nathalie; Bertrand, Yves; Kebaili, Kamila; Cuzzubbo, Daniela; Cannas, Giovanna; Martin, Cyril; Connes, Philippe

2016-01-01

Red blood cell (RBC) deformability is severely decreased in patients with sickle cell anemia (SCA), which plays a role in the pathophysiology of the disease. However, investigation of RBC deformability from SCA patients demands careful methodological considerations. We assessed RBC deformability by

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

DEFF Research Database (Denmark)

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

2011-01-01

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

Manufacturing of the L band 9-cell niobium cavity

International Nuclear Information System (INIS)

Matsuoka, Masanori; Ohkubo, Kohichi; Yamanaka, Toshiyuki; Kako, Eiji; Saito, Kenji; Shishido, Toshio; Ono, Masaaki; Noguchi, Shuichi.

1993-01-01

Since 1990, L-band niobium superconducting cavities have been developed with collaboration between our company and National Laboratory for High Energy Physics (KEK). The manufacturing procedure and the performance of 9-cell superconducting cavity are presented. The maximum accelerating gradient of 12 MV/m was attained in a cold test. (author)

The effect of cyclosporin A on the primary immune response to allogeneic red cells in rabbits.

Science.gov (United States)

Smith, G N

1982-01-01

Cyclosporin A (CSA) has been used in an attempt to suppress the primary immune response of HgA(A)-negative rabbits to A-positive red cells. The immune response was assessed by measuring the survival of a small intravenous (i.v.) dose of 51Cr-labelled A-positive cells and by testing the serum of the immunized rabbits for anti-A. In one experiment, eight A-negative rabbits were given a first i.v. injection of A-positive red cells, and CSA (25 mg/kg/day) in olive oil was given by mouth for 17-34 days. There was no evidence of impaired alloimmunization compared with the responses in control animals treated with olive oil alone. In a second experiment, eight A-negative rabbits were given a first injection of A-positive muscularly (i.m.), and CSA (25 mg/kg/day) in miglyol was given by im.m. injection for 10 days. Six of these rabbits were rendered unresponsive, and the remaining two, who showed impaired survival of the monitoring red cells, produced only low anit-A titres. Seven out of eight controls given i.m. miglyol without CSA responded with good anti-A production. Rabbits that were unresponsive to A-positive red cells responded normally to sheep red blood cells 15 weeks after CSA treatment. Higher serum levels of CSA were found following i.m. administration of the drug but treatment by this route as associated with severe toxicity in some rabbits. PMID:7056563

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

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

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

DEFF Research Database (Denmark)

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

Red blood cells (RBC) from reptiles appear not to express regulatory volume increase (RVI) upon shrinkage (Kristensen et al., 2008). In other vertebrates, the RVI response is primarily mediated by activation of the Na+/H+ exchanger (NHE-1) and we, therefore decided to investigate whether red cells...... of reptiles express a different NHE-1 that responds less to volume activation compared to other vertebrates or simply lack the Na+/H+ exchanger. Using various tissues from the ball python (Python regius), Cane toad (Bufo marinus) and European perch (Perca fluviatilis), cDNA libraries were created...

Yersinia enterocolitica septicaemia from transfusion of red cell concentrate stored for 16 days.

OpenAIRE

Jones, B L; Saw, M H; Hanson, M F; Mackie, M J; Scott, J; Murphy, W G

1993-01-01

Two cases of transfusion transmitted Yersinia enterocolitica biotype 3, serotype 09 infection occurred in south east Scotland within four months of each other. In one case, a 79 year old man died the day after receiving a unit of red cell concentrate that had been stored for 29 days after donation. In the second case a 78 year old man died three days after transfusion of a unit of red cell concentrate that had been collected 16 days before transfusion. The donors of both units had no symptoms...

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.

Long-term in vivo survival of Rh(D)-negative donor red cells in a patient with anti-LW

International Nuclear Information System (INIS)

Chaplin, H.; Hunter, V.L.; Rosche, M.E.; Shirey, R.S.

1985-01-01

The present study documents immediate and long-term survival of crossmatch-incompatible Rh(D)-negative donor red cells in a patient with anti-LW. A 67-year-old group A Rh(D)-positive man was admitted for urgent coronary artery bypass surgery. The direct antiglobulin test (DAT) was weakly positive in two of five laboratories. His serum contained anti-LW (two laboratories); his red cells were LW negative (three antisera). Two siblings were LW-positive. Surgery was delayed, and 3 ml Rh(D)-negative crossmatch-incompatible red cells stored in citrate-phosphate-dextrose-adenine-one were labeled with 25 microCi of 51 Cr and injected. Immediate survival was approximately 100 percent with 92 percent survival at 20 hours. Six daily blood samples showed a decreased red cell lifespan, (T 1/2 . 14 days). Because of medical complications, 4 units of Rh(D)-negative crossmatch-incompatible blood were then transfused without clinical or hemolytic reaction. The anti-IgG DAT became stronger. In vivo survival of the remaining 51 Cr-RBCs became normal (T 1/2 28 days over the succeeding 20 days). Following transfusion, no change in serum antibody strength was demonstrated by double-blind titration of seven coded samples. The observations support modest reduction of lifespan for 3 ml of LW-positive red cells, but normal survival following subsequent transfusion of approximately 700 ml of LW-positive red cells

Pure red cell aplasia in a simultaneous pancreas-kidney transplantation patient: inside the erythroblast

Directory of Open Access Journals (Sweden)

Francesca Labbadia

2012-09-01

Full Text Available A case of pure red cell aplasia in a simultaneous kidney-pancreas transplant recipient on immunosuppressive therapy is reported here. The patient presented with anemia unresponsive to erythropoietin treatment. Bone marrow cytomorphology was highly suggestive of parvovirus pure red cell aplasia, which was confirmed with serology and polymerase chain reaction positive for parvovirus B19 DNA in peripheral blood. After the administration of intravenous immunoglobulin the anemia improved with a rising number of the reticulocytes.

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

Directory of Open Access Journals (Sweden)

Virgilio L. Lew

2017-12-01

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

High-speed video capillaroscopy method for imaging and evaluation of moving red blood cells

Science.gov (United States)

Gurov, Igor; Volkov, Mikhail; Margaryants, Nikita; Pimenov, Aleksei; Potemkin, Andrey

2018-05-01

The video capillaroscopy system with high image recording rate to resolve moving red blood cells with velocity up to 5 mm/s into a capillary is considered. Proposed procedures of the recorded video sequence processing allow evaluating spatial capillary area, capillary diameter and central line with high accuracy and reliability independently on properties of individual capillary. Two-dimensional inter frame procedure is applied to find lateral shift of neighbor images in the blood flow area with moving red blood cells and to measure directly the blood flow velocity along a capillary central line. The developed method opens new opportunities for biomedical diagnostics, particularly, due to long-time continuous monitoring of red blood cells velocity into capillary. Spatio-temporal representation of capillary blood flow is considered. Experimental results of direct measurement of blood flow velocity into separate capillary as well as capillary net are presented and discussed.

Engineered band structure for an enhanced performance on quantum dot-sensitized solar cells

Energy Technology Data Exchange (ETDEWEB)

Jin, Bin Bin [Key Laboratory of Macromolecular Science of Shaanxi Province and School of Materials Science and Engineering, Shaanxi Normal University, Xi' an 710062 (China); Department of Chemical Engineering, Institute of Chemical Industry, Shaanxi Institute of Technology, Xi' an 710300 (China); Wang, Ye Feng [School of Chemistry and Chemical Engineering, Shaanxi Normal University, Xi' an 710062 (China); Wei, Dong; Chen, Yu; Zeng, Jing Hui, E-mail: jhzeng@ustc.edu [Key Laboratory of Macromolecular Science of Shaanxi Province and School of Materials Science and Engineering, Shaanxi Normal University, Xi' an 710062 (China); Cui, Bin [School of Chemistry and Materials Science, Northwestern University, Xi' an 710620 (China)

2016-06-20

A photon-to-current efficiency of 2.93% is received for the Mn-doped CdS (MCdS)-quantum dot sensitized solar cells (QDSSCs) using Mn:ZnO (MZnO) nanowire as photoanode. Hydrothermal synthesized MZnO are spin-coated on fluorine doped tin oxide (FTO) glass with P25 paste to serve as photoanode after calcinations. MCdS was deposited on the MZnO film by the successive ionic layer adsorption and reaction method. The long lived excitation energy state of Mn{sup 2+} is located inside the conduction band in the wide bandgap ZnO and under the conduction band of CdS, which increases the energetic overlap of donor and acceptor states, reducing the “loss-in-potential,” inhibiting charge recombination, and accelerating electron injection. The engineered band structure is well reflected by the electrochemical band detected using cyclic voltammetry. Cell performances are evidenced by current density-voltage (J-V) traces, diffuse reflectance spectra, transient PL spectroscopy, and incident photon to current conversion efficiency characterizations. Further coating of CdSe on MZnO/MCdS electrode expands the light absorption band of the sensitizer, an efficiency of 4.94% is received for QDSSCs.

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...

Seventy-five genetic loci influencing the human red blood cell

NARCIS (Netherlands)

van der Harst, P.; Zhang, W.; Mateo Leach, I.; Rendon, A.; Verweij, N.; Sehmi, J.; Paul, D.S.; Elling, U.; Allayee, H.; Li, X.; Radhakrishnan, A.; Tan, S.T.; Voss, K.; Weichenberger, C.X.; Albers, C.A.; Al-Hussani, A.; Asselbergs, F.W.; Ciullo, M.; Danjou, F.; Dina, C.; Esko, T.; Evans, D.M.; Franke, L.; Gogele, M.; Hartiala, J.; Hersch, M.; Holm, H.; Hottenga, J.J.; Kanoni, S.; Kleber, M.E.; Lagou, V.; Langenberg, C.; Lopez, L.M.; Lyytikainen, L.P.; Melander, O.; Murgia, F.; Nolte, I.M.; O'Reilly, P.F.; Padmanabhan, S.; Parsa, A.; Pirastu, N.; Porcu, E.; Portas, L.; Prokopenko, I.; Ried, J.S.; Shin, S.Y.; Tang, C.S.; Teumer, A.; Traglia, M.; Ulivi, S.; Westra, H.J.; Yang, J.; Zhao, J.H.; Anni, F.; Abdellaoui, A.; Attwood, A.; Balkau, B.; Bandinelli, S.; Bastardot, F.; Benyamin, B.; Boehm, B.O.; Cookson, W.O.; Das, D; de Bakker, P.I.; de Boer, R.A.; de Geus, E.J.; de Moor, M.H.; Dimitriou, M.; Domingues, F.S.; Doring, A.; Engstrom, G.; Eyjolfsson, G.I.; Ferrucci, L.; Fischer, K.; Galanello, R.; Garner, S.F.; Genser, B.; Gibson, Q.D.; Girotto, G.; Gudbjartsson, D.F.; Harris, S.E.; Hartikainen, A.L.; Hastie, C.E.; Hedblad, B.; Illig, T.; Jolley, J.; Kahonen, M.; Kema, I.P.; Kemp, J.P.; Liang, L.; Lloyd-Jones, H.; Loos, R.J.; Meacham, S.; Medland, S.E.; Meisinger, C.; Memari, Y.; Mihailov, E.; Miller, K.; Moffatt, M.F.; Nauck, M., et al.

2012-01-01

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

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.

Cation depletion by the sodium pump in red cells with pathologic cation leaks. Sickle cells and xerocytes.

OpenAIRE

Joiner, C H; Platt, O S; Lux, S E

1986-01-01

The mechanism by which sickle cells and xerocytic red cells become depleted of cations in vivo has not been identified previously. Both types of cells exhibit elevated permeabilities to sodium and potassium, in the case of sickle cells, when deoxygenated. The ouabain-insensitive fluxes of sodium and potassium were equivalent, however, in both cell types under these conditions. When incubated 18 hours in vitro, sickle cells lost cations but only when deoxygenated. This cation depletion was blo...

Quantitative spectroscopic J-band study of red supergiants in Perseus OB-1

International Nuclear Information System (INIS)

Gazak, J. Zachary; Kudritzki, Rolf; Davies, Ben; Bergemann, Maria; Plez, Bertrand

2014-01-01

We demonstrate how the metallicities of red supergiant (RSG) stars can be measured from quantitative spectroscopy down to resolutions of ≈3000 in the J-band. We have obtained high resolution spectra on a sample of the RSG population of h and χ Persei, a double cluster in the solar neighborhood. We show that careful application of the MARCS model atmospheres returns measurements of Z consistent with solar metallicity. Using two grids of synthetic spectra–one in pure LTE and one with non-LTE (NLTE) calculations for the most important diagnostic lines–we measure Z = +0.04 ± 0.10 (LTE) and Z = –0.04 ± 0.08 (NLTE) for the sample of eleven RSGs in the cluster. We degrade the spectral resolution of our observations and find that those values remain consistent down to resolutions of less than λ/δλ of 3000. Using measurements of effective temperatures we compare our results with stellar evolution theory and find good agreement. We construct a synthetic cluster spectrum and find that analyzing this composite spectrum with single-star RSG models returns an accurate metallicity. We conclude that the RSGs make ideal targets in the near infrared for measuring the metallicities of star forming galaxies out to 7-10 Mpc and up to 10 times farther by observing the integrated light of unresolved super star clusters.

Study on the relationship between red blood cell immunity and lipid peroxidation in patients with endometriosis

International Nuclear Information System (INIS)

Yang Jingxiu; Shi Shaohong; Wang Yuping; Xie Xueqin; Qin Jibao

2005-01-01

Objective: To assess the relationship between red blood cell immunity and lipid peroxidation (LPO) in patients with endometriosis. Methods: The percentage of positive red blood cell c3b receptor rosette (RBC c3b -RR) and red blood cell immune complex rosette (RBC-ICR) were examined in 54 patients with endometriosis and 30 controls. Serum levels of malondialdehyde (MDA), superoxidase (SOD) and glutathione peroxidase (GSH-PX) were measured by chemocolorimetry in these subjects. Results: Percentage of positive RBC-ICR and MDA levels were significantly higher in patients with endometriosis than those in controls (P c3b RR, SOD, GSH-PX, SOD/MDA ratio were significantly lower in patients with endometriosis than those in controls (P c3b -RR was negatively correlated with MDA levels (r= -0. 4428, P < 0.05) and RBC-ICRR was positively correlated with MDA(r=0.5488, P0.05). Conclusion: The lower red cell immune adhesion function was closely associated with the disturbance of metabolism of lipid peroxidation in patients with endometriosis. (authors)

Assessment of red cell sodium transport in essential hypertension

International Nuclear Information System (INIS)

Mahoney, J.R.; Etkin, N.L.; McSwigan, J.D.; Eaton, J.W.

1982-01-01

Abnormal erythrocyte Na+ transport has been reported in patients with essential hypertension and some first-degree relatives. The two major techniques now employed for estimating Na+ transport--Na+/Li+ countertransport and Na+/K+ cotransport--are rather intricate and time consuming. Furthermore, the precise nature of the transport processes being measured is not clear. We have developed a simpler, more direct technique based on measurement of 22Na+ accumulation by erythrocytes. 22Na+ uptake by red cells from patients with essential hypertension averages twice normal. Indeed, of 21 patients with essential hypertension, only 2 patients had values within the upper end of the normal range. In 12 patients with secondary hypertension and no family history of essential hypertension, erythrocyte 22Na+ accumulation was within normal limits. Control experiments indicate that our technique for estimating red cell 22Na+ uptake is highly reproducible and shows little day-to-day variation. This procedure for the assessment of erythrocyte Na+ transport should be useful in differential diagnosis and the presymptomatic identification of individuals genetically prone to essential hypertension

Red Maca (Lepidium meyenii) did not affect cell viability despite increased androgen receptor and prostate-specific antigen gene expression in the human prostate cancer cell line LNCaP.

Science.gov (United States)

Díaz, P; Cardenas, H; Orihuela, P A

2016-10-01

We examined whether aqueous extract of Lepidium meyenii (red Maca) could inhibit growth, potentiate apoptotic activity of two anticancer drugs Taxol and 2-methoxyestradiol (2ME) or change mRNA expression for the androgen target genes, androgen receptor (Ar) and prostate-specific antigen (Psa) in the human prostate cancer cell line LNCaP. Red Maca aqueous extract at 0, 10, 20, 40 or 80 μg/ml was added to LNCaP cells, and viability was evaluated by the MTS assay at 24 or 48 hr after treatment. Furthermore, LNCaP cells were treated with 80 μg/ml of red Maca plus Taxol or 2ME 5 μM and viability was assessed 48 hr later. Finally, LNCaP cells were treated with red Maca 0, 20, 40 or 80 μg/ml, and 12 hr later, mRNA level for Ar or Psa was assessed by real-time PCR. Treatment with red Maca did not affect viability of LNCaP cells. Apoptotic activity induced by Taxol and 2ME in LNCaP cells was not altered with red Maca treatment. Relative expression of the mRNA for Ar and Psa increased with red Maca 20 and 40 μg/ml, but not at 80 μg/ml. We conclude that red Maca aqueous extract does not have toxic effects, but stimulates androgen signalling in LNCaP cells. © 2016 Blackwell Verlag GmbH.

Assessment of changes in plasma hemoglobin and potassium levels in red cell units during processing and storage.

Science.gov (United States)

Saini, Nishant; Basu, Sabita; Kaur, Ravneet; Kaur, Jasbinder

2015-06-01

Red cell units undergo changes during storage and processing. The study was planned to assess plasma potassium, plasma hemoglobin, percentage hemolysis during storage and to determine the effects of outdoor blood collection and processing on those parameters. Blood collection in three types of blood storage bags was done - single CPDA bag (40 outdoor and 40 in-house collection), triple CPD + SAGM bag (40 in-house collection) and quadruple CPD + SAGM bag with integral leukoreduction filter (40 in-house collection). All bags were sampled on day 0 (day of collection), day 1 (after processing), day 7, day 14 and day 28 for measurement of percentage hemolysis and potassium levels in the plasma of bag contents. There was significant increase in percentage hemolysis, plasma hemoglobin and plasma potassium level in all the groups during storage (p levels during the storage of red blood cells. Blood collection can be safely undertaken in outdoor blood donation camps even in hot summer months in monitored blood transport boxes. SAGM additive solution decreases the red cell hemolysis and allows extended storage of red cells. Prestorage leukoreduction decreases the red cell hemolysis and improves the quality of blood. Copyright © 2015 Elsevier Ltd. All rights reserved.

Pure Red Cell Aplasia Associated with Good Syndrome

Directory of Open Access Journals (Sweden)

Masayuki Okui

2017-04-01

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

Pure red cell aplasia following irradiation of an asymptomatic thymoma

International Nuclear Information System (INIS)

Shibata, Kazuo; Masaoka, Akira; Mizuno, Takeo; Ichimura, Hideki

1982-01-01

An unusual case of pure red-cell aplasia (PRCA) developed sixteen days after irradiation of an asymptomatic thymoma. After removal of the encapsulated thymoma there was no improvement in the anemia, and no response to adrenocortical and anabolic steroid hormones or immunosuppressive agents. (author)

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....

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

Liberal red blood cell transfusions impair quality of life after cardiac surgery.

Science.gov (United States)

González-Pérez, A; Al-Sibai, J Z; Álvarez-Fernández, P; Martínez-Camblor, P; Argüello-Junquera, M; García-Gala, J M; Martínez-Revuelta, E; Silva, J; Morís, C; Albaiceta, G M

2018-03-12

The optimal blood management after cardiac surgery remains controversial. Moreover, blood transfusions may have an impact on long-term outcomes. The aim of this study is to characterize the impact of liberal red blood cell transfusions on Health-Related Quality of life (HRQoL) after cardiac surgery. We studied a cohort of 205 consecutive patients after ICU discharge. Baseline characteristics and clinical data were recorded, and HRQoL was assessed using the EuroQoL-5D instrument, applied 6 months after ICU discharge. A specific question regarding the improvement in the quality of life after the surgical intervention was added to the HRQoL questionnaire. Risk factors related to impaired quality of life were identified using univariate comparisons and multivariate regression techniques. The median (interquartile range, IQR) of transfused red blood cells was 3 (1-4). Among 205 patients, 178 were studied 6 months after discharge. Impairment in at least one dimension of the EuroQoL-5D questionnaire was observed in 120 patients, with an overall score of 0.8 (IQR 0.61-1). The number of red blood cell transfusions was related to an impaired HRQoL (OR 1.17 per additional unit, 95% confidence interval 1.03-1.36, p=0.03), a trend to lower visual analog scale score (coefficient -0.75 per additional unit, 95% confidence interval -1.61 to 0.1, p=0.09) and an absence of improvement in HRQoL after surgery compared to the previous status (OR 1.13, 95% confidence interval 1.03-1.25, p=0.01). Liberal red blood cell transfusions increase the risk of impaired HRQoL after cardiac surgery. Copyright © 2018 Elsevier España, S.L.U. y SEMICYUC. All rights reserved.

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.

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

Directory of Open Access Journals (Sweden)

Liu Chengqian

2011-05-01

Full Text Available Abstract Reverse transcription-polymerase chain reaction (RT-PCR has limited sensitivity when treating complicated samples, such as feces, waste-water in farms, and nucleic acids, protein rich tissue samples, all the factors may interfere with the sensitivity of PCR test or generate false results. In this study, we developed a sensitive RT-PCR, combination of red blood cell adsorption, for detecting Newcastle disease virus (NDV. One pair of primers which was highly homologous to three NDV pathotypes was designed according to the consensus nucleocapsid protein (NP gene sequence. To eliminate the interfere of microbes and toxic substances, we concentrated and purified NDV from varied samples utilizing the ability of NDV binding red blood cells (RBCs. The RT-PCR coupled with red blood cell adsorption was much more sensitive in comparison with regular RT-PCR. The approach could also be used to detect other viruses with the property of hemagglutination, such as influenza viruses.

Adaptive and automatic red blood cell counting method based on microscopic hyperspectral imaging technology

Science.gov (United States)

Liu, Xi; Zhou, Mei; Qiu, Song; Sun, Li; Liu, Hongying; Li, Qingli; Wang, Yiting

2017-12-01

Red blood cell counting, as a routine examination, plays an important role in medical diagnoses. Although automated hematology analyzers are widely used, manual microscopic examination by a hematologist or pathologist is still unavoidable, which is time-consuming and error-prone. This paper proposes a full-automatic red blood cell counting method which is based on microscopic hyperspectral imaging of blood smears and combines spatial and spectral information to achieve high precision. The acquired hyperspectral image data of the blood smear in the visible and near-infrared spectral range are firstly preprocessed, and then a quadratic blind linear unmixing algorithm is used to get endmember abundance images. Based on mathematical morphological operation and an adaptive Otsu’s method, a binaryzation process is performed on the abundance images. Finally, the connected component labeling algorithm with magnification-based parameter setting is applied to automatically select the binary images of red blood cell cytoplasm. Experimental results show that the proposed method can perform well and has potential for clinical applications.

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

International Nuclear Information System (INIS)

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

1990-01-01

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

Automated red blood cell depletion in ABO incompatible grafts in the pediatric setting.

Science.gov (United States)

Del Fante, Claudia; Scudeller, Luigia; Recupero, Santina; Viarengo, Gianluca; Boghen, Stella; Gurrado, Antonella; Zecca, Marco; Seghatchian, Jerard; Perotti, Cesare

2017-12-01

Bone marrow ABO incompatible transplantations require graft manipulation prior to infusion to avoid potentially lethal side effects. We analyzed the influence of pre-manipulation factors (temperature at arrival, transit time, time of storage at 4°C until processing and total time from collection to red blood cell depletion) on the graft quality of 21 red blood cell depletion procedures in ABO incompatible pediatric transplants. Bone marrow collections were processed using the Spectra Optia ® (Terumo BCT) automated device. Temperature at arrival ranged between 4°C and 6°C, median transit time was 9.75h (range 0.33-28), median time of storage at 4°-6°C until processing was 1.8h (range 0.41-18.41) and median time from collection to RBC depletion was 21h (range1-39.4). Median percentage of red blood cell depletion was 97.7 (range 95.4-98.5), median mononuclear cells recovery was 92.2% (range 40-121.2), median CD34+ cell recovery was 93% (range 69.9-161.2), median cell viability was 97.7% (range 94-99.3) and median volume reduction was 83.9% (range 82-92). Graft quality was not significantly different between BM units median age. Our preliminary data show that when all good manifacturing practices are respected the post-manipulation graft quality is excellent also for those units processed after 24h. Copyright © 2017 Elsevier Ltd. All rights reserved.

Red cell concentrate storage and transport temperature.

Science.gov (United States)

Hancock, V; Cardigan, R; Thomas, S

2011-10-01

This study investigated the current U.K. guidelines for storage and transport of red cell concentrates (RCC) in saline, adenine, glucose and mannitol (SAGM). The guidelines stipulate storage at 2-6 °C but allow exposure to between 1-10 °C core temperature in a single occurrence of less than 5 h and a surface temperature of 2-10 °C for no more than 12 h during transportation. Twenty RCC units in SAGM were selected on the day of blood collection (day 0) and in vitro quality was tested pre- and post-temperature deviation at 10 °C and up to day 42 of storage. Each group of 10 RCC units was incubated for either 12 h or for both 5 and 12 h. Haemolysis was below the 0·8% U.K. limit at day 42 in all units, although there was an unexpected trend towards lower haemolysis in packs incubated for 5 and 12 h rather than just 12 h alone. Supernatant potassium was significantly higher than reference data on day 35 (P levels of adenosine triphosphate and, 2,3-diphosphoglycerate to reference data from previous studies, throughout storage. These results suggest that exposure to 10 °C for 12 h or for 5 and 12 h did not adversely affect in vitro red cell quality for the remainder of the components shelf life. © 2011 The Authors. Transfusion Medicine © 2011 British Blood Transfusion Society.

Evaluation of Antiproliferative Activity of Red Sorghum Bran Anthocyanin on a Human Breast Cancer Cell Line (MCF-7)

International Nuclear Information System (INIS)

Devi, P.S.; Kumar, M.S.; Das, A.S.M.

2011-01-01

Breast cancer is a leading cause of death in women worldwide both in the developed and developing countries. Thus effective treatment of breast cancer with potential antitumour drugs is important. In this paper, human breast cancer cell line MCF-7 has been employed to evaluate the antiproliferative activity of red sorghum bran anthocyanin. The present investigation showed that red sorghum bran anthocyanin induced growth inhibition of MCF-7 cells at significant level. The growth inhibition is dose dependent and irreversible in nature. When MCF-7 cells were treated with red sorghum bran anthocyanins due to activity of anthocyanin morphological changes were observed. The morphological changes were identified through the formation of apoptopic bodies. The fragmentation by these anthocyanins on DNA to oligonuleosomal-sized fragments, is a characteristic of apoptosis, and it was observed as concentration-dependent. Thus, this paper clearly demonstrates that human breast cancer cell MCF-7 is highly responsive by red sorghum bran anthocyanins result from the induction of apoptosis in MCF-7 cells.

Development and application of resistive pulse spectroscopy: studies on the size, form and deformability of red blood cells

Energy Technology Data Exchange (ETDEWEB)

Yee, J.P.

1979-01-01

The following studies were conducted using the resistive pulse spectroscopy (RPS) technique: cumulative spectra and individual pulse forms for rigid latex polymer spheres; acquisition and analysis of RPS spectral data by means of special computer program; interaction of red blood cells with glutaraldehyde; membrane properties of erythrocytes undergoing abrupt osmotic hemolysis; reversible effects of the binding of chlorpromazine HCl at the red cell membrane surface; effects of high cholesterol diet on erythrocytes of guinea pigs; and multi-population analysis for a mixture of fetal and maternal red cells. (HLW)

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...

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 ...

Role of hemolysis in red cell adenosine triphosphate release in simulated exercise conditions in vitro.

Science.gov (United States)

Mairbäurl, Heimo; Ruppe, Florian A; Bärtsch, Peter

2013-10-01

Specific adenosine triphosphate (ATP) release from red blood cells has been discussed as a possible mediator controlling microcirculation in states of decreased tissue oxygen. Because intravascular hemolysis might also contribute to plasma ATP, we tested in vitro which portion of ATP release is due to hemolysis in typical exercise-induced strains to the red blood cells (shear stress, deoxygenation, and lactic acidosis). Human erythrocytes were suspended in dextran-containing media (hematocrit 10%) and were exposed to shear stress in a rotating Couette viscometer at 37°C. Desaturation (oxygen saturation of hemoglobin ∼20%) was achieved by tonometry with N2 before shear stress exposure. Cells not exposed to shear stress were used as controls. Na lactate (15 mM), lactic acid (15 mM, pH 7.0), and HCl (pH 7.0) were added to simulate exercise-induced lactic acidosis. After incubation, extracellular hemoglobin was measured to quantify hemolysis. ATP was measured with the luciferase assay. Shear stress increased extracellular ATP in a stress-related and time-dependent manner. Hypoxia induced a ∼10-fold increase in extracellular ATP in nonsheared cells and shear stress-exposed cells. Lactic acid had no significant effect on ATP release and hemolysis. In normoxic cells, approximately 20%-50% of extracellular ATP was due to hemolysis. This proportion decreased to less than 10% in hypoxic cells. Our results indicate that when exposing red blood cells to typical strains they encounter when passing through capillaries of exercising skeletal muscle, ATP release from red blood cells is caused mainly by deoxygenation and shear stress, whereas lactic acidosis had only a minor effect. Hemolysis effects were decreased when hemoglobin was deoxygenated. Together, by specific release and hemolysis, extracellular ATP reaches values that have been shown to cause local vasodilatation.

Band 3 in aging and neurological disease.

Science.gov (United States)

Kay, M M

1991-01-01

Senescent cell antigen appears on old cells and marks them for death by initiating the binding of IgG autoantibody and subsequent removal by phagocytes in mammals and other vertebrates. We have created a synthetic aging antigen that blocks binding of IgG to senescent cells in vitro. Synthetic senescent cell antigen might be effective in preventing cellular destruction in vivo in certain diseases, and can be used to manipulate cellular life span in situ. Senescent cell antigen is generated by the modification of an important structural and transport membrane molecule, protein band 3. Band 3 is present in cellular, nuclear, Golgi, and mitochondrial membranes as well as in cell membranes. Band 3 proteins in nucleated cells participate in cell surface patching and capping. Band 3 maintains acid-base balance by mediating the exchange of anions (e.g., chloride, bicarbonate), and is the binding site for glycolytic enzymes. It is responsible for CO2 exchange in all tissues and organs. Thus, it is the most heavily used anion transport system in the body. Band 3 is a major transmembrane structural protein which attaches the plasma membrane to the internal cell cytoskeleton by binding to band 2.1 (ankyrin). Oxidation generates senescent cell antigen in situ. Band 3 is present in the central nervous system, and differences have been described in band 3 between young and aging brain tissue. One autosomal recessive neurological disease, choreoacanthocytosis, is associated with band 3 abnormalities. The 150 residues of the carboxyl terminus segment of band 3 appear to be altered. In brains from Alzheimer's disease patients, antibodies to aged band 3 label the amyloid core of classical plaques and the microglial cells located in the middle of the plaque in tissue sections, and an abnormal band 3 in immunoblots. Band 3 protein(s) in mammalian brain performs the same functions as that of erythroid band 3. These functions is anion transport, ankyrin binding, and generation of

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.

Controlling the conduction band offset for highly efficient ZnO nanorods based perovskite solar cell

International Nuclear Information System (INIS)

Dong, Juan; Shi, Jiangjian; Li, Dongmei; Luo, Yanhong; Meng, Qingbo

2015-01-01

The mechanism of charge recombination at the interface of n-type electron transport layer (n-ETL) and perovskite absorber on the carrier properties in the perovskite solar cell is theoretically studied. By solving the one dimensional diffusion equation with different boundary conditions, it reveals that the interface charge recombination in the perovskite solar cell can be suppressed by adjusting the conduction band offset (ΔE C ) at ZnO ETL/perovskite absorber interface, thus leading to improvements in cell performance. Furthermore, Mg doped ZnO nanorods ETL has been designed to control the energy band levels. By optimizing the doping amount of Mg, the conduction band minimum of the Mg doped ZnO ETL has been raised up by 0.29 eV and a positive ΔE C of about 0.1 eV is obtained. The photovoltage of the cell is thus significantly increased due to the relatively low charge recombination

Light spectrum regulates cell accumulation during daytime in the raphidophyte Chattonella antiqua causing noxious red tides.

Science.gov (United States)

Shikata, Tomoyuki; Matsunaga, Shigeru; Kuwahara, Yusuke; Iwahori, Sho; Nishiyama, Yoshitaka

2016-07-01

Most marine raphidophyte species cause noxious red tides in temperate coastal areas around the world. It is known that swimming abilities enable raphidophytes to accumulation of cells and to actively acquire light at surface layers and nutrients over a wide depth range. However, it remains unclear how the swimming behavior is affected by environmental conditions, especially light condition. In the present study, we observed the accumulation of the harmful red-tide raphidophyte Chattonella antiqua under various light conditions during the daytime in the laboratory. When exposed to ultraviolet-A/blue light (320-480nm) or red light (640-680nm) from above, cells moved downward. In the case of blue light (455nm), cells started to swim downward after 5-15min of irradiation at a photon flux density≥10μmolm(-2)s(-1). When exposed to monochromatic lights (400-680nm) from the side, cells moved away from the blue light source and then descended, but just moved downward under red light. However, mixing of green/orange light (520-630nm) diminished the effects of blue light. When exposed to a mixture of 30μmolm(-2)s(-1) of blue light (440nm) and ≥6μmolm(-2)s(-1) of yellow light (560nm) from above, cells did not move downward. These results indicate that blue light induces negative phototaxis and ultraviolet-A/blue and red lights induce descending, and green/orange light cancels out their effects in C. antiqua. Copyright © 2016 Elsevier B.V. All rights reserved.

Deep-Red Fluorescent Gold Nanoclusters for Nucleoli Staining: Real-Time Monitoring of the Nucleolar Dynamics in Reverse Transformation of Malignant Cells.

Science.gov (United States)

Wang, Xiaojuan; Wang, Yanan; He, Hua; Ma, Xiqi; Chen, Qi; Zhang, Shuai; Ge, Baosheng; Wang, Shengjie; Nau, Werner M; Huang, Fang

2017-05-31

Nucleoli are important subnuclear structures inside cells. We report novel fluorescent gold nanoclusters (K-AuNCs) that are able to stain the nucleoli selectively and make it possible to explore the nucleolar morphology with fluorescence imaging technique. This novel probe is prepared through an easy synthesis method by employing a tripeptide (Lys-Cys-Lys) as the surface ligand. The properties, including deep-red fluorescence emission (680 nm), large Stocks shift, broad excitation band, low cytotoxicity, and good photostability, endow this probe with potential for bioanalytical applications. Because of their small size and their positively charged surface, K-AuNCs are able to accumulate efficiently at the nucleolar regions and provide precise morphological information. K-AuNCs are also used to monitor the nucleolar dynamics along the reverse-transformation process of malignant cells, induced by the agonist of protein A, 8-chloro-cyclic adenosine monophosphate. This gives a novel approach for investigating the working mechanism of antitumor drugs.

Levels of glutathione and 2,3-diphosphoglycerate in the red blood cells of Australian Aborigines.

Science.gov (United States)

Agar, N S

1980-01-01

There were no significant differences in packed cell volume (PCV) and red cell 2,3-diphosphoglycerate (2,3-DPG) levels in Australian Aborigines and Caucasians. A highly significant negative correlation was found between PCV and 2,3-DPG in both Aborigines (r = 0.251; n = 231) and Caucasians (r = 0.435; n = 227). Levels of reduced glutathione (GSH) in the red blood cells of Aborigines were significantly lower (P < 0.001) compared to those of Caucasians. There was a significant negative correlation between PCV and GSH in both the groups; (Aborigines r = -0.637, n = 115; Caucasians r = 0.388, n = 111).

Correlation of serum unconjugated oestriol to red cell 2,3-diphosphoglycerate levels in diabetic pregnancy.

Science.gov (United States)

Madsen, H; Ditzel, J

1983-03-01

In order to evaluate the possible underlying factors for the increase in red cell 2,3-diphosphoglycerate content observed in late diabetic pregnancy, its relationship with serum unconjugated oestriol, human placental lactogen, haemoglobin and hydrogen ion concentrations was investigated in 42 pregnant diabetic women. A significant correlation was found between red cell 2,3-diphosphoglycerate and serum unconjugated oestriol (r = 0.54, p less than 0.001), whereas no correlation was present between 2,3-diphosphoglycerate and the following variables: arterial pH, haemoglobin concentration and human placental lactogen. The content of 2,3-diphosphoglycerate correlated significantly with haemoglobin-oxygen affinity expressed as P50 at pH 7.4 (r = 0.34, p less than 0.05). The results of this study indicate that serum unconjugated oestriol may participate in the regulation of red cell 2,3-diphosphoglycerate content and thereby of the maternal blood oxygen release to the fetus.

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 ...

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 ...

Relationship between serum 25-hydroxyvitamin D and red blood cell indices in German adolescents.

Science.gov (United States)

Doudin, Asmma; Becker, Andreas; Rothenberger, Aribert; Meyer, Thomas

2018-04-01

Since the impact of vitamin D on red blood cell formation has not been well studied, we aimed at assessing the putative link between serum 25-hydroxyvitamin D (25[OH]D) concentrations and hematological markers of erythropoiesis in a large cohort of German adolescents aged 11 to 17 years. In total, 5066 participants from the population-based, nationally representative KiGGS study (Kinder- und Jugendgesundheitssurvey, German Health Interview and Examination Survey for Children and Adolescents) were grouped into either tertiles or clinically accepted cutoff levels for serum 25(OH)D. Results demonstrated significant and inverse correlations between 25(OH)D levels and several hematological parameters including hemoglobin concentration (r = - 0.04, p = 0.003), mean corpuscular hemoglobin (r = - 0.11, p < 0.001), red blood cell count (r = - 0.04, p = 0.002), and soluble transferrin receptor (r = - 0.1, p < 0.001), whereas, in contrast, serum 25(OH)D was positively correlated to the mean corpuscular volume of erythrocytes (r = 0.08, p < 0.001). Multinomial regression models adjusted for clinically relevant confounders confirmed statistically significant differences between the two strata of 25(OH)D groups with respect to red blood cell markers (hemoglobin concentration, red blood cell count, mean corpuscular volume, and corpuscular hemoglobin, as well as iron and soluble transferrin receptor). The link between serum 25(OH)D and several important hematological parameters may point to an inhibitory role of vitamin D in the regulation of erythropoiesis in adolescents. What is Known: • The physiological effects of vitamin D on calcium homeostasis and bone metabolism have been established. • However, much less is known about the impact of circulating vitamin D on erythropoiesis. What is New: • Data from the KiGGS study in German adolescents demonstrated significant associations between serum vitamin D concentrations and red

The empirical Gaia G-band extinction coefficient

Science.gov (United States)

Danielski, C.; Babusiaux, C.; Ruiz-Dern, L.; Sartoretti, P.; Arenou, F.

2018-06-01

Context. The first Gaia data release unlocked the access to photometric information for 1.1 billion sources in the G-band. Yet, given the high level of degeneracy between extinction and spectral energy distribution for large passbands such as the Gaia G-band, a correction for the interstellar reddening is needed in order to exploit Gaia data. Aims: The purpose of this manuscript is to provide the empirical estimation of the Gaia G-band extinction coefficient kG for both the red giants and main sequence stars in order to be able to exploit the first data release DR1. Methods: We selected two samples of single stars: one for the red giants and one for the main sequence. Both samples are the result of a cross-match between Gaia DR1 and 2MASS catalogues; they consist of high-quality photometry in the G-, J- and KS-bands. These samples were complemented by temperature and metallicity information retrieved from APOGEE DR13 and LAMOST DR2 surveys, respectively. We implemented a Markov chain Monte Carlo method where we used (G - KS)0 versus Teff and (J - KS)0 versus (G - KS)0, calibration relations to estimate the extinction coefficient kG and we quantify its corresponding confidence interval via bootstrap resampling. We tested our method on samples of red giants and main sequence stars, finding consistent solutions. Results: We present here the determination of the Gaia extinction coefficient through a completely empirical method. Furthermore we provide the scientific community with a formula for measuring the extinction coefficient as a function of stellar effective temperature, the intrinsic colour (G - KS)0, and absorption.

Red blood cell transfusions and tissue oxygenation in anemic hematology outpatients

NARCIS (Netherlands)

Yuruk, Koray; Bartels, Sebastiaan A.; Milstein, Dan M. J.; Bezemer, Rick; Biemond, Bart J.; Ince, Can

2012-01-01

BACKGROUND: There is little clinical evidence that red blood cell (RBC) transfusions improve oxygen availability at the microcirculatory level. We tested the hypotheses that anemia in chronically anemic patients with relatively healthy microcirculation would be associated with low tissue hemoglobin

Adverse effects to transfusion with red donor blood cells are frequent

DEFF Research Database (Denmark)

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

2014-01-01

Adverse effects to transfusion with red donor blood cells are potentially life-threatening. Due to screening, transmission of infectious diseases has decreased; however, the risk is still present. Various immune reactions are common including simple allergic reactions as well as devastating...

Small volume transfusion of irradiated red blood cells using satellite bags in very low birth weight infants

International Nuclear Information System (INIS)

Yamagiwa, Kazuhiro; Honda, Yoshinobu; Sakuma, Kimiko; Igarashi, Etsuo; Watanabe, Masahiko; Ujiie, Niro; Suzuki, Hitoshi; Ohto, Hitoshi

1993-01-01

We have treated anemia of prematurity with concentrated red cells divided into 3 packs by using the Sterile Connection Device (SCD, USA). This study was performed to reveal the influence for very low birth weight infants of transfusion of red cells stored after irradiation. The following facts were observed in infants after transfusion: (1) no change in sodium and potassium level and leucocyte count, (2) increased amount of total bilirubin but no change in unbound bilirubin level, (3) decrease in platelet count less than 50,000/mm 3 . According to these results we conclude that the transfusion of concentrated red blood cells stored within 2 weeks after irradiation was safe even for very low birth weight infants. (author)

Suppression of Red Blood Cell Autofluorescence for Immunocytochemistry on Fixed Embryonic Mouse Tissue.

Science.gov (United States)

Whittington, Niteace C; Wray, Susan

2017-10-23

Autofluorescence is a problem that interferes with immunofluorescent staining and complicates data analysis. Throughout the mouse embryo, red blood cells naturally fluoresce across multiple wavelengths, spanning the emission and excitation spectra of many commonly used fluorescent reporters, including antibodies, dyes, stains, probes, and transgenic proteins, making it difficult to distinguish assay fluorescence from endogenous fluorescence. Several tissue treatment methods have been developed to bypass this issue with varying degrees of success. Sudan Black B dye has been commonly used to quench autofluorescence, but can also introduce background fluorescence. Here we present a protocol for an alternative called TrueBlack Lipofuscin Autofluorescence Quencher. The protocol described in this unit demonstrates how TrueBlack efficiently quenches red blood cell autofluorescence across red and green wavelengths in fixed embryonic tissue without interfering with immunofluorescent signal intensity or introducing background staining. We also identify optimal incubation, concentration, and multiple usage conditions for routine immunofluorescence microscopy. © 2017 by John Wiley & Sons, Inc. Copyright © 2017 John Wiley & Sons, Inc.

Variation of morphology, karyotype and protein band pattern of adenium (Adenium obesum varieties

Directory of Open Access Journals (Sweden)

PRABANG SETYONO

2009-07-01

Full Text Available Hastuti D, Suranto, Setyono P. 2009. Variation of morphology, karyotype and protein band pattern of adenium (Adenium obesum varieties. Nusantara Bioscience 1: 78-83. The aim of this research to find out the Adenium obesum variation from six varieties, namely: obesum, cery, red lucas, red fanta , white bigben and harry potter based on morphology, karyotype, as well as protein banding pattern. The chromosome preparation was made using semi-permanent squash method from the tip of root plant; while protein banding pattern was made using SDS-PAGE method. Qualitative data included shape and color of the leave and flower described from each variety. Data were presented in morphometry and analyzed using ANOVA and then followed by DMRT with 5% of confidence levels, indicated significance difference. Protein banding pattern, the root, stem, leave and all organs were analyzed using Hierarchical Cluster Analysis method with Average Linkage (between Groups using SPSS 10.0. The result of research shows that the six A. obesum varieties have morphological character with no variation of light green to dark green leave, not hairy, smooth leave bone, meanwhile for light red to dark red flower crown color although some of them are white and the same funnel color, yellow. All varieties of A. obesum have same number of chromosome, 2n = 22 and shows the difference ranging from 2.56 to 5.13 um. In the banding pattern formed qualitatively, there is variation among the six varieties.

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.

X-ray microanalysis of Plasmodium falciparum and infected red blood cells: effects of qinghaosu and chloroquine on potassium, sodium, and phosphorus composition

International Nuclear Information System (INIS)

Lee, P.; Ye, Z.; Van Dyke, K.; Kirk, R.G.

1988-01-01

Cryosections of human red blood cells infected by Plasmodium falciparum were analyzed by energy dispersive x-ray microanalysis to determine the elemental composition of the parasites and their red cell hosts separately. The effects of two antimalarial drugs, qinghaosu and chloroquine, on potassium, sodium, and phosphorus concentrations were studied. Malarial infection causes a decrease in potassium concentration and an increase in sodium concentration in the host red cells. The drastic change in the cation composition, however, occurs only in red cells infected by late stage parasites (late trophozoite and schizont). Red cells infected by early stage parasites (ring stage) show only small changes in sodium concentration. Furthermore, the noninfected red cells in parasitized cultures show no difference in composition from those of normal red cells. Treatment of the parasitized cultures with qinghaosu (10(-6) M) or chloroquine (10(-6) M) for 8 hr causes phosphorus concentration of both early and late parasites to decrease. An 8 hr treatment with qinghaosu also produces a reduction in potassium and an increase in sodium concentrations in early and late parasites. In contrast, 8 hr treatment with chloroquine only causes a change in the sodium and potassium concentrations of the late stage parasites and does not affect the early stage parasites

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.

The effect of additives on red cell 2,3 diphosphoglycerate levels in CPDA preservatives.

Science.gov (United States)

Vora, S; West, C; Beutler, E

1989-01-01

Forty-two chemical substances, chosen because they might influence red cell metabolism, were screened for effect on red cell adenosine triphosphate and 2,3 diphosphoglycerate (2,3 DPG) levels during storage in CPD or CPDA-1 at 4 degrees C. Of these substances, six appeared on initial screening to increase 2,3 DPG levels during storage; on repeated examination, four compounds, i.e., oxalate, glyoxalate, ethyl oxaloacetate, and L-phenylalanyl-L-alanine, consistently increased 2,3 DPG levels during storage. It was shown that glyoxalate was converted rapidly to oxalate in blood, presumably through the lactate dehydrogenase reaction. Ethyl oxaloacetate is known to hydrolyze, giving rise to oxalate. Thus, the effect of both glyoxalate and ethyl oxaloacetate can be explained by the formation of oxalate, a compound already known to increase 2,3 DPG levels. The effect of L-phenylalanyl-L-alanine remains to be explained, but it may be hydrolyzed to L-alanine and L-phenylalanine, both of which are thought to have the capacity to increase red cell 2,3 DPG levels by inhibiting pyruvate kinase activity.

Astrobiological implications of dim light phototrophy in deep-sea red clays

Science.gov (United States)

Das, Anindita; Singh, Tanya; LokaBharathi, P. A.; Dhakephalkar, Prashant K.; Mallik, Sweta; Kshirsagar, Pranav R.; Khadge, N. H.; Nath, B. Nagender; Bhattacharya, Satadru; Dagar, Aditya Kumar; Kaur, Prabhjot; Ray, Dwijesh; Shukla, Anil D.; Fernandes, Christabelle E. G.; Fernandes, Sheryl O.; Thomas, Tresa Remya A.; Mamatha, S. S.; Mourya, Babu Shashikant; Meena, Ram Murti

2017-02-01

Red clays of Central Indian Basin (CIB) under influence of trace of Rodriguez Triple Junction exhibited chemoautotrophy, low temperature hydrothermal alterations and photoautotrophic potential. Seamount flank TVBC-08, hosting such signatures revealed dominance of aerobic anoxygenic phototroph Erythrobacter, with 93% of total 454 pyrosequencing tags. Subsequently, enrichments for both aerobic (Erythrobacter) and anaerobic anoxygenic phototrophs (green and purple sulphur bacteria) under red and white LED light illumination, with average irradiance 30.66 W m-2, were attempted for three red-clay sediment cores. Successful enrichments were obtained after incubation for c.a. 120 days at 4°± 2 °C and 25°± 2 °C, representing ambient psychrophilic and low temperature hydrothermal alteration conditions respectively. During hydrothermal cooling, a microbial succession from anaerobic chemolithotrophy to oxygenic photoautotrophy through anaerobic/aerobic anoxygenic phototrophic microbes is indicated. Spectral absorbance patterns of the methanol extracted cell pellets showed peaks corresponding to metal sulphide precipitations, the Soret band of chlorosome absorbance by photosystem II and absence of peaks at Qy transition band. Dendritic nano-structures of metal sulphides are common in these sediments and are comparable with other sulphidic paleo-marine Martian analogues. Significant blue and redshifts have been observed for the experimental samples relative to the un-inoculated medium. These observations indicate the propensity of metal-sulphide deposits contributing to chemiluminiscence supporting the growth of phototrophs at least partially, in the otherwise dark abyss. The effects of other geothermal heat and light sources are also under further consideration. The potential of phototrophic microbial cells to exhibit Doppler shift in absorbance patterns is significant towards understanding planetary microbial habitability. Planetary desiccation could considerably

Intermediate band solar cell simulation use InAs quantum dot in GaAs

International Nuclear Information System (INIS)

Hendra P, I. B.; Rahayu, F.; Sahdan, M. F.; Darma, Y.

2015-01-01

Intermediate band solar cell (IBSC) has become a new approach in increasing solar cell efficiency significantly. One way to create intermediate band is by proposing quantum dots (QD) technology. One of the important aspects in utilizing IBSC is the absorption of light. In this work we simulated the influence of QD arrangement in order to increase absorption coefficient and solar cell efficiency. We also simulated the influence of QD size to capture a wider light spectrum. We present a simple calculation method with low computing power demand. Results show that the increasing in quantum dot size can increase in capturing wider spectrum of light. Arrangement InAs QD in bulk material GaAs can capture wider spectrum of light and increase the absorption coefficient. The arrangement InAs QD 2 nm in GaAs bulk can increase solar cell efficiency up to 49.68%

The rise and fall of red cell mass measurement in polycythemia vera.

Science.gov (United States)

Tefferi, Ayalew

2005-05-01

The total blood volume (BV) consists of the part occupied by red blood cells (RBC), which is referred to as red cell mass (RCM), and that occupied by plasma (ie, plasma volume). Quantitative laboratory measurements that are pertinent to RBC, including RBC count, hematocrit (Hct), and hemoglobin (Hgb) are expressed in reference to a given volume of whole blood and are therefore influenced by plasma volume. Consequently, a "direct" RCM measurement has been promoted as a more accurate indicator of the body's red cell content. In accordance with this view, an international group of investigators, then identified as the Polycythemia Vera Study Group (PVSG), recommended that RCM be measured and only if elevated should a patient be considered for participation in a series of clinical trials in PV that were conducted more than 30 years ago. By default, the 'study eligibility' criteria used in these studies became 'diagnostic' criteria without any systematic evaluation for diagnostic accuracy. Furthermore, over the years, it has become evident that RCM measurement is a cumbersome and costly test that is also suboptimal in its diagnostic accuracy. As a result, the specific procedure has been abandoned by the majority of hematologists in certain countries and instead physicians are increasingly using bone marrow histology, serum erythropoietin level, and other disease-characteristic biologic markers as diagnostic tools.

The dual roles of red blood cells in tissue oxygen delivery

DEFF Research Database (Denmark)

Jensen, Frank Bo

2009-01-01

Vertebrate red blood cells (RBCs) seem to serve tissue oxygen delivery in two distinct ways. Firstly, RBCs enable the adequate transport of O2 between respiratory surfaces and metabolizing tissues by means of their high intracellular concentration of hemoglobin (Hb), appropriate allosteric...

Historical time trends in red blood cell usage in the Netherlands

NARCIS (Netherlands)

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

2016-01-01

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

Historical time trends in red blood cell usage in the Netherlands

NARCIS (Netherlands)

van Hoeven, L.R.; Koopman, M.M.W.; Koffijberg, Hendrik; Roes, K.C.B.; Janssen, M.P.

2016-01-01

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

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)

Condition of red tide appearance in Wakasa Bay based on Terra, Aqua/MODIS images

Science.gov (United States)

Aoyama, Takashi; Oya, Hiroshi

2006-12-01

Since June, 2004, studies on triggering factors of the red tide have been carried out in Awara Space Radio Observatory (ASRO), Fukui University of Technology utilizing directly received data of MODIS on the Terra and Aqua satellites which have been acquired in ASRO. Preliminary results of the data analyses for the period from July, 2001 to April, 2005 indicate conditions, for the appearance of the red tide bloom in Wakasa bay as follows: (1) the threshold amount of chlorophyll-a is close to 1.5mg/m 3, (2) the range of sea surface temperature (SST) is limited in a range from 12 to 20 °C and (3) the period of sunlit time in spring is also a significantly sensitive factor. We propose here to utilize MODIS band1 images corresponding to a red band with spatial resolution of 250m together with NDVI (Normalized Difference Vegetation Index) images which has also spatial resolution of 250m, for the confirmation of the red tide. The problem of coincidence between colored region due to SS (Suspended Sediment) and red tide region using only band1 of MODIS, has been solved by using NDVI images in addition to band1 images together as two dimensional diagram.

Enhanced persistent red luminescence in Mn2+-doped (Mg,Zn)GeO3 by electron trap and conduction band engineering

Science.gov (United States)

Katayama, Yumiko; Kayumi, Tomohiro; Ueda, Jumpei; Tanabe, Setsuhisa

2018-05-01

The effect of Zn substitution on the persistent luminescence properties of MgGeO3:Mn2+-Ln3+ (Ln = Eu and Yb) red phosphors was investigated. The intensity of the persistent luminescence of the Eu3+ co-doped phosphors increased with increasing Zn content, whereas that of the Yb3+ co-doped samples decreased. For both series of lanthanide co-doped samples, the thermoluminescence (TL) glow peak shifted to the lower temperature side with increasing Zn content. These persistent luminescence properties were well explained in terms of lowering of the bottom of the conduction band relative to the ground state of the divalent lanthanide ions. Especially, in Eu3+ co-doped system, TL peak shifted from 520 K to 318 K by 50% Zn substitution. The persistent radiance of the (Mg0.5 Zn0.5)GeO3: Mn2+-Eu3+ sample at 1 h after ceasing UV light was 46 times stronger than that of MgGeO3:Mn2+-Eu3+, and 11 times stronger than that of ZnGa2O4: Cr3+ standard deep red persistent phosphor.

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

CERN Document Server

Krüger, Timm

2012-01-01

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

Increased theta band EEG power in sickle cell disease patients

Directory of Open Access Journals (Sweden)

Case M

2017-12-01

Full Text Available Michelle Case,1 Sina Shirinpour,1 Huishi Zhang,1 Yvonne H Datta,2 Stephen C Nelson,3 Karim T Sadak,4 Kalpna Gupta,2 Bin He1,5 1Department of Biomedical Engineering, 2Department of Medicine, University of Minnesota, 3Pediatric Hematology-Oncology, Children’s Hospitals and Clinics of Minnesota, 4Pediatric Hematology-Oncology, University of Minnesota Masonic Children’s Hospital, 5Institute for Engineering in Medicine, University of Minnesota, Minneapolis, MN, USA Objective: Pain is a major issue in the care of patients with sickle cell disease (SCD. The mechanisms behind pain and the best way to treat it are not well understood. We studied how electroencephalography (EEG is altered in SCD patients. Methods: We recruited 20 SCD patients and compared their resting state EEG to that of 14 healthy controls. EEG power was found across frequency bands using Welch’s method. Electrophysiological source imaging was assessed for each frequency band using the eLORETA algorithm. Results: SCD patients had increased theta power and decreased beta2 power compared to controls. Source localization revealed that areas of greater theta band activity were in areas related to pain processing. Imaging parameters were significantly correlated to emergency department visits, which indicate disease severity and chronic pain intensity. Conclusion: The present results support the pain mechanism referred to as thalamocortical dysrhythmia. This mechanism causes increased theta power in patients. Significance: Our findings show that EEG can be used to quantitatively evaluate differences between controls and SCD patients. Our results show the potential of EEG to differentiate between different levels of pain in an unbiased setting, where specific frequency bands could be used as biomarkers for chronic pain. Keywords: sickle cell disease, electroencephalography, chronic pain, electrophysiological source imaging, thalamocortical dysrhythmia

Umbilical nucleated red blood cell as a sign of fetal distress

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Torkestani F

2008-06-01

Full Text Available Background: The presence of increased numbers of nucleated red blood cell (NRBC in the umbilical cord blood has been associated with states of relative hypoxia. Nucleated red blood cell counts are a potentially useful tool in estimating the degree and timing of intrauterine hypoxia. This may have important implication in determining causality in case of compromised infant. Cord blood NRBC counts may be obtained noninvasively from an otherwise discarded specimen and analyzed by personnel on equipment readily available in most hospital laboratories. Since the aim of monitoring of fetal heart is early diagnosis of hypoxia, we studied the relationship between abnormal fetal heart rate with the number of nucleated red blood cells (NRBC in the umbilical cord blood.Methods: We performed this research at Hazrat Zeynab Hospital on 130 full-term newborns (65 cases of fetal distress and 65 normal cases between July 2005 and July 2006. The NRBC counts of newborns with abnormal fetal heart rate were compared with those of normal newborns and correlations with other parameters including Apgar score, hemoglobin level, condition of newborns in the first 24 hours of the birth and birth weight.Results: The mean NRBC count in the fetal distress group was 9.45 ± 8.75 and that of the normal group was 9.17 ± 8.76 per 100 white cells (p=0.89. The mean duration between diagnosis of fetal distress to birth was equal to 1.2± 0.77 hours. Furthermore, there was no meaningful correlation between number of NRBC and Apgar score, hemoglobin, birth weight and condition of newborns in the first 24 hours.Conclusion: If the fetus is born a short time after the diagnosis of distress with no risk factors for hypoxia, the NRBC count for cord blood is not elevated.

A case of multiple squamous cell carcinomas arising from red tattoo pigment

Directory of Open Access Journals (Sweden)

E. Maxim, BS, MS

2017-12-01

Full Text Available Ornamental tattooing involves the administration of exogenous pigments into the skin to create a permanent design. Our case focuses on a 62-year-old woman who presented with an inflamed enlarging nodule on her right proximal calf, which arose within the red pigment of an ornamental tattoo. The nodule was diagnosed as squamous cell carcinoma (SCC and subsequently excised. Over the course of the following year, the patient was diagnosed with a total of five additional SCCs that also arose within the red pigment of the tattoo. The increased popularity of tattooing and the lack of industry safety standards for tattoo ink production, especially metal-laden red pigments, may lead to more cases of skin cancer arising within tattoos among patients of all ages.

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

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.

CHARACTERIZATION OF ENU-INDUCED MUTATIONS IN RED BLOOD CELL STRUCTURAL PROTEINS

Directory of Open Access Journals (Sweden)

Katrina Kildey

2013-03-01

Full Text Available Murine models with modified gene function as a result of N-ethyl-N-nitrosourea (ENU mutagenesis have been used to study phenotypes resulting from genetic change. This study investigated genetic factors associated with red blood cell (RBC physiology and structural integrity that may impact on blood component storage and transfusion outcome. Forward and reverse genetic approaches were employed with pedigrees of ENU-treated mice using a homozygous recessive breeding strategy. In a “forward genetic” approach, pedigree selection was based upon identification of an altered phenotype followed by exome sequencing to identify a causative mutation. In a second strategy, a “reverse genetic” approach based on selection of pedigrees with mutations in genes of interest was utilised and, following breeding to homozygosity, phenotype assessed. Thirty-three pedigrees were screened by the forward genetic approach. One pedigree demonstrated reticulocytosis, microcytic anaemia and thrombocytosis. Exome sequencing revealed a novel single nucleotide variation (SNV in Ank1 encoding the RBC structural protein ankyrin-1 and the pedigree was designated Ank1EX34. The reticulocytosis and microcytic anaemia observed in the Ank1EX34 pedigree were similar to clinical features of hereditary spherocytosis in humans. For the reverse genetic approach three pedigrees with different point mutations in Spnb1 encoding RBC protein spectrin-1β, and one pedigree with a mutation in Epb4.1, encoding band 4.1 were selected for study. When bred to homozygosity two of the spectrin-1β pedigrees (a, b demonstrated increased RBC count, haemoglobin (Hb and haematocrit (HCT. The third Spnb1 mutation (spectrin-1β c and mutation in Epb4.1 (band 4.1 did not significantly affect the haematological phenotype, despite these two mutations having a PolyPhen score predicting the mutation may be damaging. Exome sequencing allows rapid identification of causative mutations and development of

Exome Genotyping Identifies Pleiotropic Variants Associated with Red Blood Cell Traits

NARCIS (Netherlands)

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

2016-01-01

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

Multi-band algorithms for the estimation of chlorophyll concentration in the Chesapeake Bay

KAUST Repository

Gilerson, Alexander; Ondrusek, Michael; Tzortziou, Maria; Foster, Robert; El-Habashi, Ahmed; Tiwari, Surya Prakash; Ahmed, Sam

2015-01-01

on the two- or three band ratio algorithms in the red/NIR part of the spectrum, which require 665, 708, 753 nm bands (or similar) and which work well in various waters all over the world. The critical 708 nm band for these algorithms is not available on MODIS

Mode multiplexing at 2×20Gbps over 19-cell hollow-core photonic band gap fibre

DEFF Research Database (Denmark)

Carpenter, Joel; Xu, Jing; Peucheret, Christophe

2012-01-01

This paper demonstrates the first mode-multiplexed system over 19-cell hollow-core photonic band gap fibre, at 2×20Gbps using the LP0,1 and LP2,1-like modes.......This paper demonstrates the first mode-multiplexed system over 19-cell hollow-core photonic band gap fibre, at 2×20Gbps using the LP0,1 and LP2,1-like modes....

Morphological and Metabolic Parameters of Red Blood Cells after Their Treatment with Ozone

Directory of Open Access Journals (Sweden)

Anna V. Deryugina

2018-01-01

Full Text Available The purpose of the study was to assess the morphology of red blood cells (RBC and the association of morphological parameters with lipid peroxidation processes and the content of organic phosphates in RBC when treating packed red blood cells with the ozonized saline solution (with an ozone concentration of 2 mg/l after different storage periods.Materials and methods. The morphology of human RBC, the concentration of malonic dialdehyde (MDA in RBC, the catalase activity, the concentration of ATP and 2,3-diphosphoglycerate (2,3-DPG were studied before and after treatment of RBC with the ozonized saline (with the ozone concentration of 2 mg/l after 7, 14, 21 and 30 days of storage.Results. The effect of ozone (2 ng/l in vitro on the packed red blood cells after 7–21 days of storage contributed to the recovery of RBC shape, increased the concentration of ATP and 2,3-DPG, and optimized the lipid peroxidation. Ozone did not demonstrate a pronounced positive effect on these parameters when the packed RBCs were stored for 30 days.Conclusion. The treatment of the packed RBCs with the ozonized saline solution (with the ozone concentration of 2 mg/l contributed to the recovery of the discocyte count due to optimization of lipid peroxidation processes in cell membranes and enhanced the synthesis of organic phosphates in cells due to the activation of glycolysis and the pentose phosphate pathway. This can be used to improve the morphological and metabolic status of the packed RBCs before their transfusion. 

Red wine consumption improves in vitro migration of endothelial progenitor cells in young, healthy individuals.

Science.gov (United States)

Hamed, Saher; Alshiek, Jonia; Aharon, Anat; Brenner, Benjamin; Roguin, Ariel

2010-07-01

Endothelial progenitor cells (EPCs) contribute to the maintenance of vascular endothelial function. The moderate consumption of red wine provides cardiovascular protection. We investigated the underlying molecular mechanism of EPC migration in young, healthy individuals who drank red wine. Fourteen healthy volunteers consumed 250 mL red wine daily for 21 consecutive days. Vascular endothelial function, plasma stromal cell-derived factor 1alpha (SDF1alpha) concentrations, and the number, migration, and nitric oxide production of EPCs were determined before and after the daily consumption of red wine. EPCs were glucose stressed to study the effect of red wine on EPC migration, proliferation, and senescence and to study the expressions of CXC chemokine receptor 4 (CXCR4) and members of the Pi3K/Akt/eNOS (phosphatidylinositol 3-kinase/protein kinase B/endothelial nitric oxide synthase) signaling pathway by Western blotting. Daily red wine consumption for 21 consecutive days significantly enhanced vascular endothelial function. Although plasma SDF1alpha concentrations were unchanged, EPC count and migration were significantly increased after this 21-d consumption period. Red wine increased the migration, proliferation, CXCR4 expression, and activity of the Pi3K/Akt/eNOS signaling pathway and decreased the extent of apoptosis in glucose-stressed EPCs. The results of the present study indicate that red wine exerts its effect through the up-regulation of CXCR4 expression and activation of the SDF1alpha/CXCR4/Pi3K/Akt/eNOS signaling pathway, which results in increased EPC migration and proliferation and decreased extent of apoptosis. Our findings suggest that these effects could be linked to the mechanism of cardiovascular protection that is associated with the regular consumption of red wine.

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.

Mechanics of extracellular vesicles derived from malaria parasiteinfected Red Blood Cells

NARCIS (Netherlands)

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

2016-01-01

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

Optimising methods of red cell sedimentation from cord blood to maximise nucleated cell recovery prior to cryopreservation.

Science.gov (United States)

Madkaikar, M; Gupta, M; Ghosh, K; Swaminathan, S; Sonawane, L; Mohanty, D

2007-01-01

Human cord blood is now an established source of stem cells for haematopoietic reconstitution. Red blood cell (RBC) depletion is required to reduce the cord blood unit volume for commercial banking. Red cell sedimentation using hydroxy ethyl starch (HES) is a standard procedure in most cord blood banks. However, while standardising the procedure for cord blood banking, a significant loss of nucleated cells (NC) may be encountered during standard HES sedimentation protocols. This study compares four procedures for cord blood processing to obtain optimal yield of nucleated cells. Gelatin, dextran, 6% HES and 6% HES with an equal volume of phosphate-buffered saline (PBS) were compared for RBC depletion and NC recovery. Dilution of the cord blood unit with an equal volume of PBS prior to sedimentation with HES resulted in maximum NC recovery (99% [99.5 +/- 1.3%]). Although standard procedures using 6% HES are well established in Western countries, they may not be applicable in India, as a variety of factors that can affect RBC sedimentation (e.g., iron deficiency, hypoalbuminaemia, thalassaemia trait, etc.) may reduce RBC sedimentation and thus reduce NC recovery. While diluting cord blood with an equal volume of PBS is a simple method to improve the NC recovery, it does involve an additional processing step.

Tannic acid and chromic chloride-induced binding of protein to red cells: a preliminary study of possible binding sites and reaction mechanisms.

Science.gov (United States)

Hunt, A F; Reed, M I

1990-07-01

The binding mechanisms and binding sites involved in the tannic acid and chromic chloride-induced binding of protein to red cells were investigated using the binding of IgA paraprotein to red cells as model systems. Inhibition studies of these model systems using amino acid homopolymers and compounds (common as red cell membrane constituents) suggest that the mechanisms involved are similar to those proposed for the conversion of hide or skin collagen to leather, as in commercial tanning. These studies also suggest that tannic acid-induced binding of IgA paraprotein to red cells involves the amino acid residues of L-arginine, L-lysine, L-histidine, and L-proline analogous to tanning with phenolic plant extracts. The amino acid residues of L-aspartate, L-glutamate and L-asparagine are involved in a similar manner in chronic chloride-induced binding of protein to red cells.

Automated high resolution full-field spatial coherence tomography for quantitative phase imaging of human red blood cells

Science.gov (United States)

Singla, Neeru; Dubey, Kavita; Srivastava, Vishal; Ahmad, Azeem; Mehta, D. S.

2018-02-01

We developed an automated high-resolution full-field spatial coherence tomography (FF-SCT) microscope for quantitative phase imaging that is based on the spatial, rather than the temporal, coherence gating. The Red and Green color laser light was used for finding the quantitative phase images of unstained human red blood cells (RBCs). This study uses morphological parameters of unstained RBCs phase images to distinguish between normal and infected cells. We recorded the single interferogram by a FF-SCT microscope for red and green color wavelength and average the two phase images to further reduced the noise artifacts. In order to characterize anemia infected from normal cells different morphological features were extracted and these features were used to train machine learning ensemble model to classify RBCs with high accuracy.

Echinochrome A Release by Red Spherule Cells Is an Iron-Withholding Strategy of Sea Urchin Innate Immunity.

Science.gov (United States)

Coates, Christopher J; McCulloch, Claire; Betts, Joshua; Whalley, Tim

2018-01-01

Cellular immune defences in sea urchins are shared amongst the coelomocytes - a heterogeneous population of cells residing in the coelomic fluid (blood equivalent) and tissues. The most iconic coelomocyte morphotype is the red spherule cell (or amebocyte), so named due to the abundance of cytoplasmic vesicles containing the naphthoquinone pigment echinochrome A. Despite their identification over a century ago, and evidence of antiseptic properties, little progress has been made in characterising the immunocompetence of these cells. Upon exposure of red spherule cells from sea urchins, i.e., Paracentrotus lividus and Psammechinus miliaris, to microbial ligands, intact microbes, and damage signals, we observed cellular degranulation and increased detection of cell-free echinochrome in the coelomic fluid ex vivo. Treatment of the cells with ionomycin, a calcium-specific ionophore, confirmed that an increase in intracellular levels of Ca2+ is a trigger of echinochrome release. Incubating Gram-positive/negative bacteria as well as yeast with lysates of red spherule cells led to significant reductions in colony-forming units. Such antimicrobial properties were counteracted by the addition of ferric iron (Fe3+), suggesting that echinochrome acts as a primitive iron chelator in echinoid biological defences. © 2017 S. Karger AG, Basel.

Protective role of Withaferin-a on red blood cell integrity during 7,12 ...

African Journals Online (AJOL)

The protective effect of Withaferin-A was assessed by measuring the status of glycoconjugates, membrane bound enzyme activity and red blood cell osmotic fragility. Oral squamous cell carcinoma was induced in the buccal pouch of Syrian golden hamsters by painting with 0.5% DMBA in liquid paraffin thrice a week for 14 ...

LETTER TO THE EDITOR: Arterio-venous flow between monochorionic twins determined during intra-uterine transfusion. Nonlinear decay of adult red blood cells

Science.gov (United States)

van Gemert, Martin J. C.; Pasman, Suzanne A.; van den Wijngaard, Jeroen P. H. M.; Lopriore, Enrico; Vandenbussche, Frank P. H. A.

2008-07-01

Recently, we derived equations relating the flow of adult red blood cells through a placental arterio-venous anastomosis with intra-uterine and post-natal measured adult hemoglobin concentrations. In this letter, we re-derived the equations, now including a more realistic nonlinear decay of adult red blood cells, and re-evaluated the measurement accuracy of the arterio-venous flow and the lifetime of the red blood cells.

On the red giant titanium oxide bands

Science.gov (United States)

Hanni, L.; Sitska, J.

1985-12-01

The dependence of TiO absorption in cool oxygen-sequence giant stars on the Teff and log g of their atmospheres is investigated theoretically on the basis of spectra simulated using the computer program described by Hanni (1983) and the giant model atmospheres of Johnson et al. (1980). The temperature dependence of the intensity jumps at the head of the alpha(1.0) band is determined from simulated spectra, and the jumps are related to spectral types using the calibration of Ridgway et al. (1980). The results are presented in tables and graphs and shown to be in good agreement with the empirical Teff/intensity-jump correlation of Boyarchuk (1969).

A method for red blood cell biotinylation in a closed system

NARCIS (Netherlands)

de Back, Djuna Z.; Vlaar, Richard; Beuger, Boukje; Daal, Brunette; Lagerberg, Johan; Vlaar, Alexander P. J.; de Korte, Dirk; van Kraaij, Marian; van Bruggen, Robin

2018-01-01

Several circumstances require the accurate measurement of red blood cell (RBC) survival and clearance, such as determination of posttransfusion recovery of stored RBCs to investigate the effect of new additive solutions. To this end, biotin as a marker of RBCs to track donor RBCs in the blood of the

Orientated hemolysis of the red blood cells of miners from uranium mines

International Nuclear Information System (INIS)

Nosek, J.

1975-06-01

The method of orientated hemolysis was used to investigate the suspension of the washed red blood cells. The control group and the test group of miners were set up. It was found that the groups did not differ either in the number of the test tubes where the hemolysis took place, or in the number of the hemolytic zones. However they did differ in the average width of the hemolytic zones and their most probable location. A more frequent occurrence of wide hemolytic zones and their placement at the end of a row of 40 test tubes has been observed in the group of miners of the uranium mines. The reason for this was not elucidated but it was shown that the phenomenon can be simulated artifically by adding uranyl and lead salts to the suspension of the red blood cells. (author)

Enhanced green fluorescent protein is a nearly ideal long-term expression tracer for hematopoietic stem cells, whereas DsRed-express fluorescent protein is not.

Science.gov (United States)

Tao, Wen; Evans, Barbara-Graham; Yao, Jing; Cooper, Scott; Cornetta, Kenneth; Ballas, Christopher B; Hangoc, Giao; Broxmeyer, Hal E

2007-03-01

Validated gene transfer and expression tracers are essential for elucidating functions of mammalian genes. Here, we have determined the suitability and unintended side effects of enhanced green fluorescent protein (EGFP) and DsRed-Express fluorescent protein as expression tracers in long-term hematopoietic stem cells (HSCs). Retrovirally transduced mouse bone marrow cells expressing either EGFP or DsRed-Express in single or mixed dual-color cell populations were clearly discerned by flow cytometry and fluorescence microscopy. The results from in vivo competitive repopulation assays demonstrated that EGFP-expressing HSCs were maintained nearly throughout the lifespan of the transplanted mice and retained long-term multilineage repopulating potential. All mice assessed at 15 months post-transplantation were EGFP positive, and, on average, 24% total peripheral white blood cells expressed EGFP. Most EGFP-expressing recipient mice lived at least 22 months. In contrast, Discosoma sp. red fluorescent protein (DsRed)-expressing donor cells dramatically declined in transplant-recipient mice over time, particularly in the competitive setting, in which mixed EGFP- and DsRed-expressing cells were cotransplanted. Moreover, under in vitro culture condition favoring preservation of HSCs, purified EGFP-expressing cells grew robustly, whereas DsRed-expressing cells did not. Therefore, EGFP has no detectable deteriorative effects on HSCs, and is nearly an ideal long-term expression tracer for hematopoietic cells; however, DsRed-Express fluorescent protein is not suitable for these cells.

Improved modification for in vitro labeling of red blood cells with Technetium-99m

International Nuclear Information System (INIS)

Gerson, B.; Ballinger, J.R.; Gulenchyn, K.Y.

1988-01-01

The authors have tested a modification of Brookhaven method for in vitro labeling of red blood cells (RBCs) with technetium-99m by adding an initial centrifugation step and performing the labeling on packed RBCs. This results in reproducible, high labeling efficiencies (99.3% +/- 0.4%, n = 50) after 15 min of incubation. The use of packed RBCs also results in a higher concentration of labeled RBCs (smaller bolus for injection) and less radiation exposure to the technologist. This technique has proved useful for radionuclide angiography, venography, gastrointestinal bleeding studies, and red cell mass determinations. It is particularly advantageous for RBC labeling in patients receiving chemotherapy

Ornamental comb colour predicts T-cell-mediated immunity in male red grouse Lagopus lagopus scoticus

Science.gov (United States)

Mougeot, Francois

2008-02-01

Sexual ornaments might reliably indicate the ability to cope with parasites and diseases, and a better ability to mount a primary inflammatory response to a novel challenge. Carotenoid-based ornaments are amongst the commonest sexual signals of birds and often influence mate choice. Because carotenoids are immuno-stimulants, signallers may trade-off allocating these to ornamental colouration or using them for immune responses, so carotenoid-based ornaments might be particularly useful as honest indicators of immuno-compentence. Tetraonid birds, such as the red grouse Lagopus lagopus scoticus, exhibit supra-orbital yellow red combs, a conspicuous ornament which functions in intra- and inter-sexual selection. The colour of combs is due to epidermal pigmentation by carotenoids, while their size is testosterone-dependent. In this study, I investigated whether comb characteristics, and in particular, comb colour, indicated immuno-competence in free-living male red grouse. I assessed T-cell-mediated immunity using a standardised challenge with phytohaemagglutinin. Red grouse combs reflect in the red and in the ultraviolet spectrum of light, which is not visible to humans but that grouse most likely see, so I measured comb colour across the whole bird visible spectrum (300 700 nm) using a reflectance spectrometer. I found that males with bigger and redder combs, but with less ultraviolet reflectance, had greater T-cell-mediated immune response. Comb colour predicted T-cell-mediated immune response better than comb size, indicating that the carotenoid-based colouration of this ornament might reliably signal this aspect of male quality.

[Optimization of trehalose loading in red blood cells before freeze-drying].

Science.gov (United States)

Zhuang, Yuan; Liu, Jing-Han; Ouyang, Xi-Lin; Chen, Lin-Feng; Che, Ji

2007-04-01

The key points for better protection of trehalose in freeze-drying red blood cells (RBCs) are to resolve non-osmosis of trehalose to red blood cells and to make cytoplasmic trehalose to reach effective concentration. This study was aimed to investigate the regularity of loading RBCs with trehalose, screen out optimal loading condition and evaluate the effect of trehalose on physico-chemical parameters of RBCs during the period of loading. The cytoplasmic trehalose concentration in red blood cells, free hemoglobin and ATP level were determined at different incubation temperatures (4, 22 and 37 degrees C), different trehaolse concentrations (0, 200, 400, 600, 800 and 1000 mmol/L) and different incubation times (2, 4, 6, 8 and 10 hours), the cytoplasmic trehalose, free hemoglobin (FHb), hemoglobin (Hb) and mean corpuscular volume (MCV) in fresh RBCs and RBCs stored for 72 hours at 4 degrees C were compared, when loading condition was ensured. The results showed that with increase of incubation temperature, time and extracellular trehalose concentration, the loading of trehalose in RBCs also increased. Under the optimal loading condition, cytoplasmic trehalose concentration and free hemoglobin level of fresh RBCs and RBCs stored for 72 hours at 4 degrees C were 65.505 +/- 6.314 mmol/L, 66.2 +/- 5.002 mmol/L and 6.567 +/- 2.568 g/L, 16.168 +/- 3.922 g/L respectively. It is concluded that the most optimal condition of loading trehalose is that fresh RBCs incubate in 800 mmol/L trehalose solution for 8 hours at 37 degrees C. This condition can result in a efficient cytoplasmic trehalose concentration. The study provides an important basis for long-term preservation of RBCs.

Age of red blood cells and mortality in the critically ill

LENUS (Irish Health Repository)

Pettila, Ville

2011-04-15

Abstract Introduction In critically ill patients, it is uncertain whether exposure to older red blood cells (RBCs) may contribute to mortality. We therefore aimed to evaluate the association between the age of RBCs and outcome in a large unselected cohort of critically ill patients in Australia and New Zealand. We hypothesized that exposure to even a single unit of older RBCs may be associated with an increased risk of death. Methods We conducted a prospective, multicenter observational study in 47 ICUs during a 5-week period between August 2008 and September 2008. We included 757 critically ill adult patients receiving at least one unit of RBCs. To test our hypothesis we compared hospital mortality according to quartiles of exposure to maximum age of RBCs without and with adjustment for possible confounding factors. Results Compared with other quartiles (mean maximum red cell age 22.7 days; mortality 121\\/568 (21.3%)), patients treated with exposure to the lowest quartile of oldest RBCs (mean maximum red cell age 7.7 days; hospital mortality 25\\/189 (13.2%)) had an unadjusted absolute risk reduction in hospital mortality of 8.1% (95% confidence interval = 2.2 to 14.0%). After adjustment for Acute Physiology and Chronic Health Evaluation III score, other blood component transfusions, number of RBC transfusions, pretransfusion hemoglobin concentration, and cardiac surgery, the odds ratio for hospital mortality for patients exposed to the older three quartiles compared with the lowest quartile was 2.01 (95% confidence interval = 1.07 to 3.77). Conclusions In critically ill patients, in Australia and New Zealand, exposure to older RBCs is independently associated with an increased risk of death.

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.

Study on Renal Anemia: A Double Tracer Study on Metabolism and Red Cell Life Span in Chronic Renal Diseases using Radioactive Iron (59Fe) and Chromium (51Cr)

International Nuclear Information System (INIS)

Jung, Kyung Tae; Lee, Mun Ho

1968-01-01

The ferrokinetics and red cell life spans of the patients with chronic glomerulonephritis were investigated by the double tracing method using radioactive iron ( 59 Fe) and chromium ( 51 Cr). According to the serum NPN levels, the patients were subdivided into 3 groups: Group 1. 6 patients, had the levels below 40 mg/dl. Group 2. 6 patients, had the levels between 41 mg/dl to 80 mg/dl. Group 3. 10 patients had the levels above 80 mg/dl. The results were as follows: 1) Red blood cell, hematocrit and hemoglobin values were moderately reduced in patients with normal serum NPN levels, while markedly reduced in patients with elevated serum NPN levels. 2) The plasma volume was increased, while the red cell volume was decreased in patients with elevated serum NPN levels, hence, total blood volume was unchanged. 3) The serum iron level was slightly reduced in patients of groups 1 and 2, while was within the normal ranges in patients of group 3. 4) i) In patients with normal serum NPN levels, the plasma iron disappearance rate, red cell iron utilization rate, red cell iron turnover rate, daily red cell iron renewal rate, circulating red cell iron and red cell iron concentration were within the normal ranges, while the plasma iron turnover rate was slightly reduced. ii) In patients with elevated serum NPN levels, the plasma iron disappearance rate was delayed, while the plasma iron turnover rate was within the normal ranges. The red cell iron utilization rate, red cell iron turnover rate and circulating red cell iron were decreased and the period in which the red cell iron utilization rate reached its peak was delayed in Group 3 patients. The daily red cell iron renewal rate and the red cell iron concentration were unchanged. iii) The mean red cell life span was within the normal ranges in patients with normal serum NPN levels, while was shortened in patients with elevated serum NPN levels.

Mixed Lichenoid and Follicular T- and B-Cell Lymphoid Reaction to Red Tattoos With Monoclonal T Cells.

Science.gov (United States)

Zaaroura, Hiba; Bergman, Reuven

2017-09-28

Pseudolymphomatous reactions have been described to occur in tattoos. Most cases have exhibited T-cell predominance and polyclonal T-cell receptor gene rearrangements. One case with monoclonal IgH gene rearrangements progressed into B-cell lymphoma. Lichenoid infiltrates are commonly described but lymphoid follicles much less frequently. We report a case with mixed lichenoid and follicular T- and B-cell reaction to red tattoos. The histopathology and the immunohistochemical studies were constant with a mixed T- and B-cell pseudolymphoma, the IgH gene rearrangement study was polyclonal, but the T-cell receptor gene rearrangement study was monoclonal. The patient who responded to intralesional corticosteroid injections remains under close scrutiny.

Neonatal nucleated red blood cells in infants of overweight and obese mothers.

Science.gov (United States)

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

2007-06-01

The perinatal outcome of the infant of obese mother is adversely affected and in theory, may involve fetal hypoxia. We hypothesized that an index of fetal hypoxia, the neonatal nucleated red blood cell (NRBC) count, is elevated in infants of overweight and obese mothers. Absolute NRBC counts taken during the first 12 hours of life in 41 infants of overweight and obese mothers were compared to 28 controls. Maternal body mass index and infant birthweight were significantly higher in the overweight and obese group (P cell and lymphocyte counts did not differ between groups. The absolute NRBC count was higher (P = 0.01), and the platelet count lower (P = 0.05) in infants of overweight and obese mothers than in controls. In stepwise regression analysis, the absolute NRBC count in infants of overweight and obese mothers remained significantly higher even after taking into account birthweight or gestational age and Apgar scores (P mothers have increased nucleated red blood cells at birth compared with controls. We speculate that even apparently healthy fetuses of overweight and obese mothers are exposed to a subtle hypoxemic environment.

Serial assessment of biochemical parameters of red cell preparations to evaluate safety for neonatal transfusions.

Science.gov (United States)

Mukherjee, Somnath; Marwaha, Neelam; Prasad, Rajendra; Sharma, Ratti Ram; Thakral, Beenu

2010-12-01

Neonatologists often prefer fresh blood (2,3 diphosphoglycerate (2,3 DPG) up to 21 days of storage. Within each group of RBC, rise in mean concentration of potassium, lactate and plasma haemoglobin from day 1 to 21 of storage was significant in CPDA-1 RBC having the highest levels at day 21. From day 3 to 21, SAGM RBC had higher mean pH value than CPDA-1 RBC though this difference was not statistically significant. SAGM RBC had highest mean glucose concentration during storage than other two types of red cell preparations (P2,3 DPG concentration from day 1 to 7 was significant (P<0.05). A positive correlation existed between mean plasma potassium and haemoglobin in all three types of red cells (r=0.726, 0.419, 0.605 for CPDA-1 RBC, SAGM RBC and whole blood respectively, P<0.005). All the three red cell preparations tested revealed biochemical changes within acceptable limits of safety till 21 days of storage. CPDA-1 RBCs had the highest degree of these changes.

The effect of curvature on the undulation spectrum of Red Blood Cell membranes

Science.gov (United States)

Kuriabova, Tatiana; Henle, Mark L.; Levine, Alex J.

2009-03-01

The human red blood cell (RBC) membrane has a composite structure of a fluid lipid bilayer tethered to an elastic 2D spectrin network. The study of the mechanical properties of RBCs is crucial to our understanding of their ability withstand large amplitude deformations during their passage through the microvasculature. The linear mechanical response of this composite membrane can be measured by observing its undulatory dynamics in thermal equilibrium, i.e. microrheology. Previous models of these dynamics postulated an effective surface tension. In this talk, we show that surface tension is not necessary. Rather, the coupling of membrane bending to spectrin network compression by curvature can account for the observed dynamics. We use a simplified theoretical model to describe the undulatory dynamics of RBCs, measured experimentally by the Popescu group.ootnotetextG. Popescu et al. ``Imaging red blood cell dynamics by quantitative phase microscopy, Blood Cells, Molecules, and Diseases, (2008), in print'' Analyzing their data using our model, we observe dramatic changes in RBC membrane elasticity associated with cells' morphological transition from discocytes to echinocyte to spherocyte.

Red blood cell labeling with technetium-99m. Effect of radiopaque contrast agents

International Nuclear Information System (INIS)

Finkel, J.; Chervu, L.R.; Bernstein, R.G.; Srivastava, S.C.

1988-01-01

Radiographic contrast agents have been reported in the literature to interfere significantly with red blood cell (RBC) labeling in vivo by Tc-99m. Moreover, in the presence of contrast agents, red cells have been known to undergo significant morphologic changes. These observations led to the current RBC labeling study in patients (N = 25) undergoing procedures with the administration of contrast media. Before and after contrast administration, blood samples were drawn from each patient into vacutainer tubes containing heparin and RBC labeling was performed using 1-ml aliquots of these samples following the Brookhaven National Laboratory protocol. The differences in average percentage labeling yield with and without contrast media were not significant. In vivo labeling in hypertensive rats with administration of contrast media up to 600 mg likewise consistently gave high labeling yields at all concentrations. Purported alterations in cell labeling attributed to contrast agents are not reflected in these studies, and other pathophysiologic factors need to be identified to substantiate the previous reports. In vitro study offers a potentially useful and simple method to delineate effects of various agents on cell labeling

Particle Simulation of Oxidation Induced Band 3 Clustering in Human Erythrocytes.

Directory of Open Access Journals (Sweden)

Hanae Shimo

2015-06-01

Full Text Available Oxidative stress mediated clustering of membrane protein band 3 plays an essential role in the clearance of damaged and aged red blood cells (RBCs from the circulation. While a number of previous experimental studies have observed changes in band 3 distribution after oxidative treatment, the details of how these clusters are formed and how their properties change under different conditions have remained poorly understood. To address these issues, a framework that enables the simultaneous monitoring of the temporal and spatial changes following oxidation is needed. In this study, we established a novel simulation strategy that incorporates deterministic and stochastic reactions with particle reaction-diffusion processes, to model band 3 cluster formation at single molecule resolution. By integrating a kinetic model of RBC antioxidant metabolism with a model of band 3 diffusion, we developed a model that reproduces the time-dependent changes of glutathione and clustered band 3 levels, as well as band 3 distribution during oxidative treatment, observed in prior studies. We predicted that cluster formation is largely dependent on fast reverse reaction rates, strong affinity between clustering molecules, and irreversible hemichrome binding. We further predicted that under repeated oxidative perturbations, clusters tended to progressively grow and shift towards an irreversible state. Application of our model to simulate oxidation in RBCs with cytoskeletal deficiency also suggested that oxidation leads to more enhanced clustering compared to healthy RBCs. Taken together, our model enables the prediction of band 3 spatio-temporal profiles under various situations, thus providing valuable insights to potentially aid understanding mechanisms for removing senescent and premature RBCs.

Particle Simulation of Oxidation Induced Band 3 Clustering in Human Erythrocytes.

Science.gov (United States)

Shimo, Hanae; Arjunan, Satya Nanda Vel; Machiyama, Hiroaki; Nishino, Taiko; Suematsu, Makoto; Fujita, Hideaki; Tomita, Masaru; Takahashi, Koichi

2015-06-01

Oxidative stress mediated clustering of membrane protein band 3 plays an essential role in the clearance of damaged and aged red blood cells (RBCs) from the circulation. While a number of previous experimental studies have observed changes in band 3 distribution after oxidative treatment, the details of how these clusters are formed and how their properties change under different conditions have remained poorly understood. To address these issues, a framework that enables the simultaneous monitoring of the temporal and spatial changes following oxidation is needed. In this study, we established a novel simulation strategy that incorporates deterministic and stochastic reactions with particle reaction-diffusion processes, to model band 3 cluster formation at single molecule resolution. By integrating a kinetic model of RBC antioxidant metabolism with a model of band 3 diffusion, we developed a model that reproduces the time-dependent changes of glutathione and clustered band 3 levels, as well as band 3 distribution during oxidative treatment, observed in prior studies. We predicted that cluster formation is largely dependent on fast reverse reaction rates, strong affinity between clustering molecules, and irreversible hemichrome binding. We further predicted that under repeated oxidative perturbations, clusters tended to progressively grow and shift towards an irreversible state. Application of our model to simulate oxidation in RBCs with cytoskeletal deficiency also suggested that oxidation leads to more enhanced clustering compared to healthy RBCs. Taken together, our model enables the prediction of band 3 spatio-temporal profiles under various situations, thus providing valuable insights to potentially aid understanding mechanisms for removing senescent and premature RBCs.

Band gap engineering of hydrogenated amorphous carbon thin films for solar cell application

Science.gov (United States)

Dwivedi, Neeraj; Kumar, Sushil; Dayal, Saurabh; Rauthan, C. M. S.; Panwar, O. S.; Malik, Hitendra K.

2012-10-01

In this work, self bias variation, nitrogen introduction and oxygen plasma (OP) treatment approaches have been used for tailoring the band gap of hydrogenated amorphous carbon (a-C:H) thin films. The band gap of a-C:H and modified a- C:H films is varied in the range from 1.25 eV to 3.45 eV, which is found to be nearly equal to the full solar spectrum (1 eV- 3.5 eV). Hence, such a-C:H and modified a-C:H films are found to be potential candidate for the development of full spectrum solar cells. Besides this, computer aided simulation with considering variable band gap a-C:H and modified a- C:H films as window layer for amorphous silicon p-i-n solar cells is also performed by AFORS-HET software and maximum efficiency as ~14 % is realized. Since a-C:H is hard material, hence a-C:H and modified a-C:H films as window layer may avoid the use of additional hard and protective coating particularly in n-i-p configuration.

Probing Xylan-Specific Raman Bands for Label-Free Imaging Xylan in Plant Cell Wall

Energy Technology Data Exchange (ETDEWEB)

Zeng, Yining; Yarbrough, John M.; Mittal, Ashutosh; Tucker, Melvin P.; Vinzant, Todd; Himmel, Michael E.

2015-06-15

Xylan constitutes a significant portion of biomass (e.g. 22% in corn stover used in this study). Xylan is also an important source of carbohydrates, besides cellulose, for renewable and sustainable energy applications. Currently used method for the localization of xylan in biomass is to use fluorescence confocal microscope to image the fluorescent dye labeled monoclonal antibody that specifically binds to xylan. With the rapid adoption of the Raman-based label-free chemical imaging techniques in biology, identifying Raman bands that are unique to xylan would be critical for the implementation of the above label-free techniques for in situ xylan imaging. Unlike lignin and cellulose that have long be assigned fingerprint Raman bands, specific Raman bands for xylan remain unclear. The major challenge is the cellulose in plant cell wall, which has chemical units highly similar to that of xylan. Here we report using xylanase to specifically remove xylan from feedstock. Under various degree of xylan removal, with minimum impact to other major cell wall components, i.e. lignin and cellulose, we have identified Raman bands that could be further tested for chemical imaging of xylan in biomass in situ.

The importance of band tail recombination on current collection and open-circuit voltage in CZTSSe solar cells

Energy Technology Data Exchange (ETDEWEB)

Moore, James E. [Naval Research Laboratory, Washington, DC 20375 (United States); Purdue University, West Lafayette, Indiana 47907 (United States); Hages, Charles J. [Purdue University, West Lafayette, Indiana 47907 (United States); Helmholtz-Zentrum Berlin für Materialien und Energie, Hahn-Meitner-Platz 1, 14109 Berlin (Germany); Agrawal, Rakesh; Lundstrom, Mark S.; Gray, Jeffery L. [Purdue University, West Lafayette, Indiana 47907 (United States)

2016-07-11

Cu{sub 2}ZnSn(S,Se){sub 4} (CZTSSe) solar cells typically exhibit high short-circuit current density (J{sub sc}), but have reduced cell efficiencies relative to other thin film technologies due to a deficit in the open-circuit voltage (V{sub oc}), which prevent these devices from becoming commercially competitive. Recent research has attributed the low V{sub oc} in CZTSSe devices to small scale disorder that creates band tail states within the absorber band gap, but the physical processes responsible for this V{sub oc} reduction have not been elucidated. In this paper, we show that carrier recombination through non-mobile band tail states has a strong voltage dependence and is a significant performance-limiting factor, and including these effects in simulation allows us to simultaneously explain the V{sub oc} deficit, reduced fill factor, and voltage-dependent quantum efficiency with a self-consistent set of material parameters. Comparisons of numerical simulations to measured data show that reasonable values for the band tail parameters (characteristic energy, capture rate) can account for the observed low V{sub oc}, high J{sub sc}, and voltage dependent collection efficiency. These results provide additional evidence that the presence of band tail states accounts for the low efficiencies of CZTSSe solar cells and further demonstrates that recombination through non-mobile band tail states is the dominant efficiency limiting mechanism.

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.

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.

Tuning into single-band red upconversion luminescence in Yb(3+)/Ho(3+) activated nano-glass-ceramics through Ce(3+) doping.

Science.gov (United States)

Chen, Daqin; Zhou, Yang; Wan, Zhongyi; Ji, Zhenguo; Huang, Ping

2015-03-28

Yb(3+)/Ho(3+) activated glass ceramics containing β-YF3 nanocrystals were successfully fabricated. The green ((5)S2/(5)F4→(5)I8) upconversion emission is dominant in the glass ceramics and is about 160 times stronger than that of the precursor glass, resulting from the partition of lanthanide activators into a low-phonon-energy crystalline lattice and the subsequent low probability of multi-phonon nonradiative relaxation from the (5)S2/(5)F4 and (5)I6 states to the lower ones. Upon the introduction of Ce(3+) ions into nano-glass-ceramics, two efficient cross-relaxation processes between Ho(3+) and Ce(3+), i.e., Ho(3+):(5)S2/(5)F4 + Ce(3+):(2)F5/2→Ho(3+):(5)F5 + Ce(3+):(2)F7/2 and Ho(3+):(5)I6 + Ce(3+):(2)F5/2→Ho(3+):(5)I7 + Ce(3+):(2)F7/2, are demonstrated to greatly suppress the population of the green-emitting (5)S2/(5)F4 state and to enhance the population of the red-emitting (5)F5 one, leading to the intense single-band red UC radiation of Ho(3+).

Application of the photoreflectance technique to the characterization of quantum dot intermediate band materials for solar cells

International Nuclear Information System (INIS)

Canovas, E.; Marti, A.; Lopez, N.; Antolin, E.; Linares, P.G.; Farmer, C.D.; Stanley, C.R.; Luque, A.

2008-01-01

Intermediate band materials rely on the creation of a new electronic band within the bandgap of a conventional semiconductor that is isolated from the conduction and valence band by a true zero density of states. Due to the presence of the intermediate band, a solar cell manufactured using these materials is capable of producing additional photocurrent, thanks to the absorption of photons with energy lower than the conventional bandgap. In this respect, the characterization of these materials by suitable techniques becomes a key element in the development of the new photovoltaic devices called intermediate band solar cells. The technique of photoreflectance is particularly suited to this purpose because it is contact-less and allows the characterization of the material without the need of actually manufacturing a complete device. Using room temperature photoreflectance we have analyzed intermediate band materials based on quantum dots and have been able to identify the energy levels involved. Also, from the photoreflectance data we have demonstrated the overlap of the wave-functions defined by the quantum dots

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

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

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.

A Randomized Clinical Trial of Red Blood Cell Transfusion Triggers in Cardiac Surgery.

Science.gov (United States)

Koch, Colleen G; Sessler, Daniel I; Mascha, Edward J; Sabik, Joseph F; Li, Liang; Duncan, Andra I; Zimmerman, Nicole M; Blackstone, Eugene H

2017-10-01

Class I evidence supporting a threshold for transfusion in the cardiac surgical setting is scarce. We randomly allocated patients to a transfusion hematocrit trigger of 24% versus 28% to compare morbidity, mortality, and resource use. From March 2007 to August 2014, two centers randomly assigned 722 adults undergoing coronary artery bypass graft surgery or valve procedures to a 24% hematocrit trigger (n = 363, low group) or 28% trigger (n = 354, high group). One unit of red blood cells was transfused if the hematocrit fell below the designated threshold. The primary endpoint was a composite of postoperative morbidities and mortality. Treatment effect was primarily assessed using an average relative effect generalized estimating equation model. At the second planned interim analysis, the a priori futility boundary was crossed, and the study was stopped. There was no detected treatment effect on the composite outcome (average relative effect odds ratio, low versus high, 0.86, 95% confidence interval: 0.29 to 2.54, p = 0.71). However, the low group received fewer red blood cell transfusions than the high group (54% versus 75%, p < 0.001), mostly administered in the operating room (low group, 112 [31%]; high group, 208 [59%]), followed by intensive care unit (low, 105 [31%]; high, 115 [34%]) and floor (low, 41 [12%]; high, 42 [13%]). The low group was exposed to lower hematocrits: median before transfusion, 22% (Q1 = 21%, Q3 = 23%) versus 24% (Q1 = 22%, Q3 = 25%). Negative exposures differed between treatment groups, with lower hematocrit in the 24% trigger group and more red blood cells used in the 28% group, but adverse outcomes did not differ. Because red blood cell use was less with a 24% trigger without adverse effects, our randomized trial results support aggressive blood conservation efforts in cardiac surgery. Copyright © 2017 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

Minimal volume regulation after shrinkage of red blood cells from five species of reptiles

DEFF Research Database (Denmark)

Kristensen, Karina; Berenbrink, Michael; Koldkjær, Pia

2008-01-01

Red blood cells (RBCs) from most vertebrates restore volume upon hypertonic shrinkage and the mechanisms underlying this regulatory volume increase (RVI) have been studied extensively in these cells. Despite the phylogenetically interesting position of reptiles, very little is known about their red...... cell function. The present study demonstrates that oxygenated RBCs in all major groups of reptiles exhibit no or a very reduced RVI upon ~ 25% calculated hyperosmotic shrinkage. Thus, RBCs from the snakes Crotalus durissus and Python regius, the turtle Trachemys scripta and the alligator Alligator...... was not characterized. It seems, therefore, that the RVI response based on NHE activation was lost among the early sauropsids that gave rise to modern reptiles and birds, while it was retained in mammals. An RVI response has then reappeared in birds, but based on activation of the NKCC. Alternatively, the absence...

Unusual expression of red fluorescence at M phase induced by anti-microtubule agents in HeLa cells expressing the fluorescent ubiquitination-based cell cycle indicator (Fucci)

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Honda-Uezono, Asumi [Section of Oral Radiation Oncology, Department of Oral Health Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8549 (Japan); Section of Maxillofacial Surgery, Department of Maxillofacial and Neck Reconstruction, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8549 (Japan); Kaida, Atsushi [Section of Oral Radiation Oncology, Department of Oral Health Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8549 (Japan); Michi, Yasuyuki; Harada, Kiyoshi [Section of Maxillofacial Surgery, Department of Maxillofacial and Neck Reconstruction, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8549 (Japan); Hayashi, Yoshiki; Hayashi, Yoshio [Department of Medicinal Chemistry, Tokyo University of Pharmacy and Life Sciences, Hachioji, Tokyo 192-0392 (Japan); Miura, Masahiko, E-mail: masa.mdth@tmd.ac.jp [Section of Oral Radiation Oncology, Department of Oral Health Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8549 (Japan)

2012-11-16

Highlights: Black-Right-Pointing-Pointer Fucci visualizes cell cycle by green and red fluorescence. Black-Right-Pointing-Pointer Plinabulin, induced unusual red fluorescence at M-phase in HeLa-Fucci cells. Black-Right-Pointing-Pointer The unusual pattern was followed by mitotic catastrophe. Black-Right-Pointing-Pointer The unusual pattern may be an early indicator of cell death in HeLa cells. -- Abstract: Plinabulin (NPI-2358) is a novel microtubule-depolymerizing agent. In HeLa cells, plinabulin arrests the cell-cycle at M phase and subsequently induces mitotic catastrophe. To better understand the effects on this compound on the cell-cycle, we used the fluorescent ubiquitination-based cell cycle indicator (Fucci), which normally enables G1 and S/G2/M cells to emit red and green fluorescence, respectively. When HeLa-Fucci cells were treated with 50 nM plinabulin, cells began to fluoresce both green and red in an unusual pattern; most cells exhibited the new pattern after 24 h of treatment. X-irradiation efficiently induced G2 arrest in plinabulin-treated cells and significantly retarded the emergence of the unusual pattern, suggesting that entering M phase is essential for induction of the pattern. By simultaneously visualizing chromosomes with GFP-histone H2B, we established that the pattern emerges after nuclear envelope breakdown but before metaphase. Pedigree assay revealed a significant relationship between the unusual expression and mitotic catastrophe. Nocodazole, KPU-133 (a more potent derivative of plinabulin), and paclitaxel also exerted similar effects. From these data, we conclude that the unusual pattern may be associated with dysregulation of late M phase-specific E3 ligase activity and mitotic catastrophe following treatment with anti-microtubule agents.

Phosphoglycolate phosphatase and 2,3-diphosphoglycerate in red cells of normal and anemic subjects.

Science.gov (United States)

Somoza, R; Beutler, E

1983-10-01

Red cell phosphoglycolate phosphatase (PGP) and 2,3-diphosphoglycerate (2,3-DPG) were investigated in normal and anemic patients and rabbits. In hemolytic anemia and blood-loss anemia, characterized by a young red cell population, there was an increase in both phosphoglycolate phosphatase activity and 2,3-diphosphoglycerate levels. In aplastic anemia, the phosphoglycolate phosphatase activity was normal, but the 2,3-diphosphoglycerate values were nonetheless increased. Thus, no relationship was found between phosphoglycolate phosphatase activity and 2,3-diphosphoglycerate levels. The lack of correlation between the activity of phosphoglycolate phosphatase and 2,3-DPG levels suggests that modulation of phosphoglycolate phosphatase activity does not control the level of 2,3-DPG in erythrocytes.

What is the band alignment of Cu2ZnSn(S,Se)4 solar cells?

DEFF Research Database (Denmark)

Crovetto, Andrea; Hansen, Ole

2017-01-01

The band alignment at the Cu2ZnSn(S,Se)4/CdS solar cell heterojunction is a controversial issue, as different measurements and calculations point to substantially different conduction band offsets (CBO). As the actual value of the CBO has profound implications on solar cell performance, the aim...... of this work is to separate genuine process-dependent variations in the CBO from errors in its experimental determination. We argue that the two most likely mechanisms responsible for real CBO variations are Fermi level pinning (which tends to decrease the CBO) and chemical interdiffusion (which tends...... measurement approaches. Interestingly, a rough correlation can be established between the CBO measured at the Cu2ZnSnS4/CdS interface by different groups and their corresponding solar cell efficiency: lower-efficiency cells often have a large "cliff-like" offset, whereas most high-efficiency cells have...

Application of MCD spectroscopy and TD-DFT to a highly non-planar porphyrinoid ring system. New insights on red-shifted porphyrinoid spectral bands.

Science.gov (United States)

Mack, John; Asano, Yoshiaki; Kobayashi, Nagao; Stillman, Martin J

2005-12-21

The first magnetic circular dichroism (MCD) spectra are reported for tetraphenyltetraacenaphthoporphyrin (TPTANP). The impact on the electronic structure of steric interactions between the fused acenaphthalene rings and the meso-tetraphenyl substituents is explored based on an analysis of the optical spectra of the Zn(II) complex (ZnTPTANP) and the free base dication species ([H4TPTANP]2+). In the case of ZnTPTANP, significant folding of the porphyrinoid ligand induces a highly unusual MCD-sign reversal providing the first direct spectroscopic evidence of ligand nonplanarity. Density functional theory (DFT) geometry optimizations for a wide range of Zn(II) porphyrinoids based on the B3LYP functional and TD-DFT calculations of the associated UV-visible absorption spectra are reported, allowing a complete assessment of the MCD data. TPTANP complexes are found to fall into a class of cyclic polyenes, termed as soft MCD chromophores by Michl (J. Pure Appl. Chem. 1980, 52, 1549.), since the signs of the Faraday A1 terms observed in the MCD spectrum are highly sensitive to slight structural changes. The origin of an unusually large red shift of the main B (or Soret) band of MTPTANP (the most red shifted ever reported for fused-ring-expanded metal porphines) and of similar red shifts observed in the spectra of other peripherally crowded porphyrinoid complexes is also explored and explained on this basis.

Stretching of red blood cells using an electro-optics trap.

Science.gov (United States)

Haque, Md Mozzammel; Moisescu, Mihaela G; Valkai, Sándor; Dér, András; Savopol, Tudor

2015-01-01

The stretching stiffness of Red Blood Cells (RBCs) was investigated using a combination of an AC dielectrophoretic apparatus and a single-beam optical tweezer. The experiments were performed at 10 MHz, a frequency high enough to avoid conductivity losses, but below the second turnover point between positive and negative dielectrophoresis. By measuring the geometrical parameters of single healthy human RBCs as a function of the applied voltage, the elastic modulus of RBCs was determined (µ = 1.80 ± 0.5 µN/m) and compared with similar values of the literature got by other techniques. The method is expected to be an easy-to-use, alternative tool to determine the mechano-elastic properties of living cells, and, on this basis, to distinguish healthy and diseased cells.

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

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Joanna F Flatt

2014-06-01

Full Text Available Stored blood components are a critical life-saving tool provided to patients by health services worldwide. Red cells may be stored for up to 42 days, allowing for efficient blood bank inventory management, but with prolonged storage comes an unwanted side-effect known as the ‘storage lesion’, which has been implicated in poorer patient outcomes. This lesion is comprised of a number of processes that are inter-dependent. Metabolic changes include a reduction in glycolysis and ATP production after the first week of storage. This leads to an accumulation of lactate and drop in pH. Longer term damage may be done by the consequent reduction in anti-oxidant enzymes, which contributes to protein and lipid oxidation via reactive oxygen species. The oxidative damage to the cytoskeleton and membrane is involved in increased vesiculation and loss of cation gradients across the membrane. The irreversible damage caused by extensive membrane loss via vesiculation alongside dehydration is likely to result in immediate splenic sequestration of these dense, spherocytic cells. Although often overlooked in the literature, the loss of the cation gradient in stored cells will be considered in more depth in this review as well as the possible effects it may have on other elements of the storage lesion. It has now become clear that blood donors can exhibit quite large variations in the properties of their red cells, including microvesicle production and the rate of cation leak. Further study of stored red blood cells from donors known to have a high or low-rate of cation leak will shed more light on the relationship between cation gradients and the manifestation of the various elements of the storage lesion.

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

Survival of the fittest?--survival of stored red blood cells after transfusion.

NARCIS (Netherlands)

Luten, M.; Roerdinkholder-Stoelwinder, B.; Bost, H.J.; Bosman, G.J.C.G.M.

2004-01-01

During the last 90 years many developments have taken place in the world of blood transfusion. Several anticoagulants and storage solutions have been developed. Also the blood processing has undergone many changes. At the moment, in The Netherlands, red blood cell (RBC) concentrates (prepared from a

Abnormally banded chromosomal regions in doxorubicin-resistant B16-BL6 murine melanoma cells.

Science.gov (United States)

Slovak, M L; Hoeltge, G A; Ganapathi, R

1986-08-01

B16-BL6 murine melanoma cells were selected for cytogenetic evaluation during the stepwise development of increasing resistance in vitro to the antitumor antibiotic, doxorubicin (DOX). Karyotypic studies demonstrated extensive heteroploidy with both numerical and structural abnormalities which were not present in the parental DOX-sensitive B16-BL6 cells. Trypsin-Giemsa banding revealed the presence of several marker chromosomes containing abnormally banding regions (ABRs) in the 44-fold B16-BL6 DOX-resistant subline. These ABRs appeared to be more homogeneously staining at the higher DOX concentrations. Length measurements (ABR index) in seven banded metaphases indicated a direct correlation with increasing DOX concentration. When the DOX-resistant cells were grown in drug-free medium for 1 yr, the drug-resistant phenotype gradually declined in parallel with the level of resistance and the ABR index. DOX-induced cytogenetic damage examined by sister chromatid exchange methodology in parental B16-BL6 cells indicated a linear sister chromatid exchange:DOX dose-response relationship. However, after continuous treatment of parental B16-BL6 cells with DOX (0.01 microgram/ml) for 30 days, sister chromatid exchange scores were found to return to base-line values. The B16-BL6 resistant cells demonstrated a cross-resistant phenotype with N-trifluoroacetyladriamycin-14-valerate, actinomycin D, and the Vinca alkaloids but not with 1-beta-D-arabinofuranosylcytosine. The results suggest that ABR-containing chromosomes in DOX-resistant sublines may represent cytogenetic alterations of specific amplified genes involved in the expression of DOX resistance. Further studies are required to identify and define the possible gene products and to correlate their relationship to the cytotoxic action of doxorubicin.

Serial assessment of biochemical parameters of red cell preparations to evaluate safety for neonatal transfusions