Red cell density is sex and race dependent in the adult.
Blumenfeld, N; Fabry, M E; Thysen, B; Nagel, R L
1988-09-01
Using a highly sensitive method for the determination of red cell densities (Percoll-Stractan continuous isopyknic gradients), we find that, in adults, this parameter varies with sex and race. Whites have red cell densities (expressed as mean corpuscular hemoglobin concentration [MCHC]) that are, on the average, 0.7 gm/dl higher than those in blacks (the difference of the means has p less than 2 x 10(-7]. White men have, on the average, 0.6 gm/dl higher MCHC than white women (the difference of the means has p less than 6 x 10(-5]. We find a strong correlation between all red cell densities and intracellular K+ and a slightly weaker correlation between red cell density and intracellular Na+ + K+. Men have an average intraerythrocytic K+ that is approximately 4.5 mmol/L of red cells less than that of women among whites as well as blacks (p less than 10(-5) and p less than 9 x 10(-4), respectively). Blacks have significantly higher plasma ferritin levels than do whites (in addition to the sex difference). Future work will have to dissect the possible causes of these differences, which include the high incidence of deletional alpha-thalassemia (-a/aa) among blacks, menstruation, hormonal effects, and the red cell transport and volume regulation differences between sexes and races. Whatever the cause of the sex and racial differences reported here, they are bound to affect the pathophysiologic expression of genetic red cell diseases that are particularly sensitive to the MCHC, such as the sickle cell syndromes.
Density increment and decreased survival of rat red blood cells induced by cadmium
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kunimoto, M.; Miura, T.
1986-01-01
Male Wistar rats were injected with CdCl/sub 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 cellsmore » 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, (/sup 3/H) diisopropylfluorophosphate ((/sup 3/H)DFP) was injected into rats. At Day 11, Cd at either 0.5 or 1.0 mg/kg was administered to (/sup 3/H)DFP-prelabeled animals. Cd administration accelerated /sup 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.« less
Isoelectric focusing of red blood cells in a density gradient stabilized column
NASA Technical Reports Server (NTRS)
Smolka, A. J. K.; Miller, T. Y.
1980-01-01
The effects of Ficoll and cell application pH on red blood cell electrophoretic mobility and focusing pH were investigated by focusing cells in a density gradient stabilized column. Sample loading, cell dispersion, column conductivity, resolution of separation, and the effect of Ampholines were examined.
Detection and quantification of subtle changes in red blood cell density using a cell phone.
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.
Method using CO for extending the useful shelf-life of refrigerated red blood cells
Bitensky, Mark W.
1995-01-01
Method using CO for extending the useful shelf-life of refrigerated red blood cells. Carbon monoxide is utilized for stabilizing hemoglobin in red blood cells to be stored at low temperature. Changes observed in the stored cells are similar to those found in normal red cell aging in the body, the extent thereof being directly related to the duration of refrigerated storage. Changes in cell buoyant density, vesiculation, and the tendency of stored cells to bind autologous IgG antibody directed against polymerized band 3 IgG, all of which are related to red blood cell senescence and increase with refrigerated storage time, have been substantially slowed when red blood cells are treated with CO. Removal of the carbon monoxide from the red blood cells is readily and efficiently accomplished by photolysis in the presence of oxygen so that the stored red blood cells may be safely transfused into a recipient.
Romero, José R; Suzuka, Sandra M; Nagel, Ronald L; Fabry, Mary E
2002-02-15
Nitric oxide (NO), essential for maintaining vascular tone, is produced from arginine by nitric oxide synthase. Plasma arginine levels are low in sickle cell anemia, and it is reported here that low plasma arginine is also found in our sickle transgenic mouse model that expresses human alpha, human beta(S), and human beta(S-Antilles) and is homozygous for the mouse beta(major) deletion (S+S-Antilles). S+S-Antilles mice were supplemented with a 4-fold increase in arginine that was maintained for several months. Mean corpuscular hemoglobin concentration (MCHC) decreased and the percent high-density red cells was reduced. Deoxy K(+) efflux is characteristic of red cells in sickle cell disease and contributes to the disease process by increasing the MCHC and rendering the cells more susceptible to polymer formation. This flux versus the room air flux was reduced in S+S-Antilles red cells from an average value of 1.6 +/- 0.3 mmol per liter of red cells x minute (FU) in nonsupplemented mice to 0.9 +/- 0.3 FU (n = 4, P < .02, paired t test) in supplemented mice. In room air, V(max) of the Ca(++)-activated K(+) channel (Gardos) was reduced from 4.1 +/- 0.6 FU (off diet) to 2.6 +/- 0.4 FU (n = 7 and 8, P < .04, t test) in arginine-supplemented mice versus clotrimazole. In conclusion, the major mechanism by which arginine supplementation reduces red cell density (MCHC) in S+S-Antilles mice is by inhibiting the Ca(++)-activated K(+) channel.
Method using CO for extending the useful shelf-life of refrigerated red blood cells
Bitensky, M.W.
1995-12-19
A method is disclosed using CO for extending the useful shelf-life of refrigerated red blood cells. Carbon monoxide is utilized for stabilizing hemoglobin in red blood cells to be stored at low temperature. Changes observed in the stored cells are similar to those found in normal red cell aging in the body, the extent thereof being directly related to the duration of refrigerated storage. Changes in cell buoyant density, vesiculation, and the tendency of stored cells to bind autologous IgG antibody directed against polymerized band 3 IgG, all of which are related to red blood cell senescence and increase with refrigerated storage time, have been substantially slowed when red blood cells are treated with CO. Removal of the carbon monoxide from the red blood cells is readily and efficiently accomplished by photolysis in the presence of oxygen so that the stored red blood cells may be safely transfused into a recipient. 5 figs.
Visible red and infrared light alters gene expression in human marrow stromal fibroblast cells.
Guo, J; Wang, Q; Wai, D; Zhang, Q Z; Shi, S H; Le, A D; Shi, S T; Yen, S L-K
2015-04-01
This study tested whether or not gene expression in human marrow stromal fibroblast (MSF) cells depends on light wavelength and energy density. Primary cultures of isolated human bone marrow stem cells (hBMSC) were exposed to visible red (VR, 633 nm) and infrared (IR, 830 nm) radiation wavelengths from a light emitting diode (LED) over a range of energy densities (0.5, 1.0, 1.5, and 2.0 Joules/cm2) Cultured cells were assayed for cell proliferation, osteogenic potential, adipogenesis, mRNA and protein content. mRNA was analyzed by microarray and compared among different wavelengths and energy densities. Mesenchymal and epithelial cell responses were compared to determine whether responses were cell type specific. Protein array analysis was used to further analyze key pathways identified by microarrays. Different wavelengths and energy densities produced unique sets of genes identified by microarray analysis. Pathway analysis pointed to TGF-beta 1 in the visible red and Akt 1 in the infrared wavelengths as key pathways to study. TGF-beta protein arrays suggested switching from canonical to non-canonical TGF-beta pathways with increases to longer IR wavelengths. Microarrays suggest RANKL and MMP 10 followed IR energy density dose-response curves. Epithelial and mesenchymal cells respond differently to stimulation by light suggesting cell type-specific response is possible. These studies demonstrate differential gene expression with different wavelengths, energy densities and cell types. These differences in gene expression have the potential to be exploited for therapeutic purposes and can help explain contradictory results in the literature when wavelengths, energy densities and cell types differ. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Fabry, M E; Romero, J R; Buchanan, I D; Suzuka, S M; Stamatoyannopoulos, G; Nagel, R L; Canessa, M
1991-07-01
We have previously demonstrated that young normal (AA) and sickle cell anemia (SS) red blood cells are capable of a volume regulatory decrease response (VRD) driven by a K:Cl cotransporter that is activated by low pH or hypotonic conditions. We now report on the characteristics of young SS cells (SS2, discocytes) capable of rapid increase in density in response to swelling. We have isolated cells with high VRD response (H-VRD) and low VRD response (L-VRD) cells by incubation and density-gradient centrifugation under hypotonic conditions. Comparison of these cells in patients homozygous for hemoglobin (Hb)S indicated that H-VRD cells have 91% more reticulocytes (P less than 9 x 10(-9) than L-VRD cells, 25% less HbF (P less than 5.5 x 10(-5), 106% more NEM (N-methylmaleimide)-stimulated K:Cl cotransport activity (P less than 2 x 10(-4), and 86% more volume-stimulated K:Cl cotransport activity (P less than 1.8 x 10(-3). H-VRD and L-VRD cells have similar G-6-PD and Na+/H+ antiport activity. In agreement with the reduced percent HbF in H-VRD cells, F cells (red blood cells that contain fetal Hb) are depleted from the H-VRD population; however, F reticulocytes are enriched in the H-VRD population to the same extent as non-F reticulocytes, which suggests that both F and non-F reticulocytes have a similar initial distribution of volume-sensitive K:Cl cotransport activity but that it may be more rapidly inactivated in F than in S reticulocytes. We find that H-VRD cells consist of 20% reticulocytes (or 79% of all reticulocytes in SS2) and 80% more mature cells. This study demonstrates the role of K:Cl cotransport in determining red blood cell density, the heterogeneity of K:Cl cotransport activity in reticulocytes, and the capacity for rapid change in the density of reticulocytes with high K:Cl cotransport activity. We speculate that the H-VRD population may be more susceptible to generation of dense and irreversibly sickled cells.
Hoffman, Joseph F
2016-12-20
The shape of the human red blood cell is known to be a biconcave disk. It is evident from a variety of theoretical work that known physical properties of the membrane, such as its bending energy and elasticity, can explain the red-blood-cell biconcave shape as well as other shapes that red blood cells assume. But these analyses do not provide information on the underlying molecular causes. This paper describes experiments that attempt to identify some of the underlying determinates of cell shape. To this end, red-blood-cell ghosts were made by hypotonic hemolysis and then reconstituted such that they were smooth spheres in hypo-osmotic solutions and smooth biconcave discs in iso-osmotic solutions. The spherical ghosts were centrifuged onto a coated coverslip upon which they adhered. When the attached spheres were changed to biconcave discs by flushing with an iso-osmotic solution, the ghosts were observed to be mainly oriented in a flat alignment on the coverslip. This was interpreted to mean that, during centrifugation, the spherical ghosts were oriented by a dense band in its equatorial plane, parallel to the centrifugal field. This appears to be evidence that the difference in the densities between the rim and the dimple regions of red blood cells and their ghosts may be responsible for their biconcave shape.
Hoffman, Joseph F.
2016-01-01
The shape of the human red blood cell is known to be a biconcave disk. It is evident from a variety of theoretical work that known physical properties of the membrane, such as its bending energy and elasticity, can explain the red-blood-cell biconcave shape as well as other shapes that red blood cells assume. But these analyses do not provide information on the underlying molecular causes. This paper describes experiments that attempt to identify some of the underlying determinates of cell shape. To this end, red-blood-cell ghosts were made by hypotonic hemolysis and then reconstituted such that they were smooth spheres in hypo-osmotic solutions and smooth biconcave discs in iso-osmotic solutions. The spherical ghosts were centrifuged onto a coated coverslip upon which they adhered. When the attached spheres were changed to biconcave discs by flushing with an iso-osmotic solution, the ghosts were observed to be mainly oriented in a flat alignment on the coverslip. This was interpreted to mean that, during centrifugation, the spherical ghosts were oriented by a dense band in its equatorial plane, parallel to the centrifugal field. This appears to be evidence that the difference in the densities between the rim and the dimple regions of red blood cells and their ghosts may be responsible for their biconcave shape. PMID:27930321
Research on fluorescence detection method of Microcystis aeruginosa
NASA Astrophysics Data System (ADS)
Wang, Xiao-xiong
2017-07-01
The paper studied the viability determination of Microcystis aeruginosa by FDA and PI staining. The staining results were measured by fluorescence microscopy. The results indicated that viable and dead cells were stained as bright green and red fluorescent respectively by FDA and PI. Through PI-FDA dual color fluorescence staining, the color of green and red distinct obviously by fluorescence microscope. The staining rate has relation with the cell density. If the cell density of M. aeruginosa was 1.0×107-1.0×109 cell·mL-1, the staining rate would be 100.0% or 98.0% by PI and of FDA respectively.
[Acute toxicity effects of three red tide algae on Brachionus plicatilis].
Zhou, Wen-Li; Xiao, Hui; Wang, You; Zhai, Hong-Chang; Tang, Xue-Xi
2008-11-01
Acute toxicity testing method was used to study effects of different density of Prorocentrum donghaiense, Heterosigma akashiwo and Alexandrium tamarense on mortality rates and population growth parameter of Brachionus plicatilis under controlled experimental conditions. Results showed that 24 h LC50 values of Prorocentrum donghaiense, Heterosigma akashiwo and Alexandrium tamarense treatment to mortality rate of Brachionus plicatilis were 3.56, 1.21 and 0.49 (x 10(4) cells/mL) respectively. Marked density effects were presented when three species of red tide microalga showed their toxicity to Brachionus plicatilis. There were significant inhibitory effects on Brachionus plicatilis when it was exposed to cells of Prorocentrum donghaiense at the concentration of 10(4) cells/mL, filtrate and cell contents of Heterosigma akashiwo at the concentration of 10(5) cells/mL, and cells, filtrate and cell contents of Alexandrium tamarense at the concentration of 10(3) cells/mL respectively. Inhibitory effects of three species of microalga on Brachionus plicatilis were enhanced with increasing of microalgal density.
Park, Kyung Hee; Kim, Tae Young; Ko, Hyun Seok; Han, Eun Mi; Lee, Suk-Ho; Kim, Jung-Hun; Lee, Jae Wook
2015-08-01
Dye-sensitized solar cells (DSSCs) were assembled using natural dyes extracted from red cabbage as a sensitizer. In this work, we investigated the adsorption characteristics and the electrochemical behavior for harvesting sunlight and electron transfer in red cabbage DSSCs under different solvents and pH. For the red cabbage dye-sensitized electrode adsorbed at pH 3.5, the solar cell yields a short-circuit current density (Jsc) of 1.60 mA/cm2, a photovoltage (Vcc) of 0.46 V, and a fill factor of 0.55, corresponding to an energy conversion efficiency (η) of 0.41%.
Yavin, E; Billia, D M
1997-03-01
Flow cytometry, light and fluorescence microscopy, and designated biochemical techniques were used to examine the type of death which occurs in cerebral cortex cells when grown under crowded vs. sparse conditions or after brief anoxia/hypoglycemia. A 4 hr episode of anoxia combined with glucose deprivation enhanced apoptotic cell death as assessed by 4',6-diamidino-2-phenylindole (DAPI) staining and reduced neutral red eye uptake. An additional form of cell death involving exclusion of the nucleus was recorded by time lapse cinematography and DAPI stain. The presence of the endonuclease inhibitor aurintricarboxylic acid (0.1 mM) reduced cell death by 56.6%, while the protein and RNA synthesis inhibitors actinomycin D and cycloheximide (each at 5 micrograms/ml) effectively decreased cell death by 83.3% and 90.6%, respectively. In contrast, 5 mM glutamate had no effect on cell death in accord with the immature state of the cells. Growth of cells under crowded conditions improved cell survival; after 2 h or 4 days in culture, cells seeded at high density (34 microgram cellular DNA/cm2) showed a nearly 3-fold decline in the amount of cell death in comparison to cells seeded at low density (5 micrograms cellular DNA/cm2). At high cell density, anoxic episodes enhanced cell death most likely by preventing a cell density-mediated rescue. Neutral red dye uptake, an index for cell viability, was enhanced with increasing cell density and in vitro maturation, but was reduced in dense cultures exposed to anoxic/hypoglycemic conditions. The data suggest that cell density may play a critical role in brain organogenesis and that anoxic stress is more deleterious in dense than sparse cell assemblies.
NASA Astrophysics Data System (ADS)
Zeidan, Adel; Yeheskely-Hayon, Daniella; Minai, Limor; Yelin, Dvir
2016-03-01
The properties of red blood cells are a remarkable indicator of the body's physiological condition; their density could indicate anemia or polycythemia, their absorption spectrum correlates with blood oxygenation, and their morphology is highly sensitive to various pathologic states including iron deficiency, ovalocytosis, and sickle cell disease. Therefore, measuring the morphology of red blood cells is important for clinical diagnosis, providing valuable indications on a patient's health. In this work, we simulated the appearance of normal red blood cells under a reflectance confocal microscope and discovered unique relations between the cells' morphological parameters and the resulting characteristic interference patterns. The simulation results showed good agreement with in vitro reflectance confocal images of red blood cells, acquired using spectrally encoded flow cytometry (SEFC) that imaged the cells during linear flow and without artificial staining. By matching the simulated patterns to the SEFC images of the cells, the cells' three-dimensional shapes were evaluated and their volumes were calculated. Potential applications include measurement of the mean corpuscular volume, cell morphological abnormalities, cell stiffness under mechanical stimuli, and the detection of various hematological diseases.
Brain nuclei in actively courting red-sided garter snakes: a paradigm of neural trimorphism.
Krohmer, Randolph W; DeMarchi, Geno A; Baleckaitis, Daniel D; Lutterschmidt, Deborah I; Mason, Robert T
2011-03-28
During the breeding season, two distinct male phenotypes are exhibited by red-sided garter snakes (Thamnophis sirtalis parietalis), with courtship behavior being directed not only toward females, but also toward a sub-population of males called she-males. She-males are morphologically identical to other males except for a circulating androgen level three times that of normal males and their ability to produce a female-like pheromone. As in other vertebrates, limbic nuclei in the red-sided garter snake brain are involved in the control of sexual behaviors. For example, an intact anterior hypothalamus pre-optic area (AHPOA) is essential for the initiation and maintenance of reproduction. To determine if brain morphology varies among the three behavioral phenotypes (i.e., males, she-males, and females) during the breeding season, we examined the volume, cell size and cell density of the AHPOA as well as a control region, the external nucleus of the optic tract (ENOT). We used Luxol Fast Blue and Ziehl's Fuchsin to visualize neurons and glial cells, respectively. No significant differences were observed among the three behavioral phenotypes in the volume, cell size or density in the control region. In contrast, the volume, cell size and density of the AHPOA of she-males were significantly greater than those of both male and female snakes. While the volume of the AHPOA was significantly greater in females compared to males, no differences were observed in cell size or density. These differences in brain morphology suggest a possible underlying mechanism for phenotypic-specific behavioral patterns. Copyright © 2010 Elsevier Inc. All rights reserved.
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.
Bordeaux, Mélanie; de Girval, Diane; Rullaud, Robin; Subileau, Maeva; Dubreucq, Eric; Drone, Jullien
2014-01-01
We have recently described the biocatalytic characterization of a self-sufficent biosynthetic alkane hydroxylase based on CYP153A13a from Alcanivorax borkumensis SK2 (thereafter A13-Red). Despite remarkable regio- and chemo-selectivity, A13-Red suffers of a difficult-to-reproduce expression and moderate operational stability. In this study, we focused our efforts on the production of A13-Red using high-cell-density cultivation (HCDC) of recombinant Escherichia coli. We achieved 455 mg (5,000 nmol) of functional enzyme per liter of culture. Tight control of cultivation parameters rendered the whole process highly reproducible compared with flask cultivations. We optimized the purification of the biocatalyst that can be performed in either two or three steps depending on the application needed to afford A13-Red up to 95 % homogeneous. We investigated different reaction conditions and found that the total turnover numbers of A13-Red during the in vitro hydroxylation of n-octane could reach up to 3,250 to produce 1-octanol (1.6 mM) over a period of 78 h.
Electrophoretic cell separation using microspheres. [purification of lymphocytes
NASA Technical Reports Server (NTRS)
Smolka, A.; Sachs, G.
1980-01-01
Methods of cell separation based on the electrokinetic properties of the cell membrane offer a degree of discrimination among cell populations which is not available with methods based on cell size or density alone. Studies aimed at extending red cell separations using microspheres to purification of lymphocytes.
Low density, resorcinol-formaldehyde aerogels
Pekala, Richard W.
1991-01-01
The polycondensation of resorcinol with formaldehyde under alkaline conditions results in the formation of surface functionalized polymer "Clusters". The covalent crosslinking of these "clusters" produces gels which when processed under supercritical conditions, produce low density, organic aerogels (density.ltoreq.100 mg/cc; cell size .ltoreq.0.1 microns). The aerogels are transparent, dark red in color and consist of interconnected colloidal-like particles with diameters of about 100.circle.. These aerogels may be further carbonized to form low density carbon foams with cell size of about 0.1 micron.
Low density, resorcinol-formaldehyde aerogels
Pekala, Richard W.
1989-01-01
The polycondensation of resorcinol with formaldehyde under alkaline conditions results in the formation of surface functionalized polymer "clusters". The covalent crosslinking of these "clusters" produces gels which when processed under supercritical conditions, produce low density, organic aerogels (density .ltoreq.100 mg/cc; cell size .ltoreq.0.1 microns). The aerogels are transparent, dark red in color and consist of interconnected colloidal-like particles with diameters of about 100 .ANG.. These aerogels may be further carbonized to form low density carbon foams with cell size of about 0.1 micron.
Low density, resorcinol-formaldehyde aerogels
Pekala, R.W.
1989-10-10
The polycondensation of resorcinol with formaldehyde under alkaline conditions results in the formation of surface functionalized polymer clusters. The covalent crosslinking of these clusters produces gels which when processed under supercritical conditions, produce low density, organic aerogels (density [<=]100 mg/cc; cell size [<=]0.1 microns). The aerogels are transparent, dark red in color and consist of interconnected colloidal-like particles with diameters of about 100 [angstrom]. These aerogels may be further carbonized to form low density carbon foams with cell size of about 0.1 micron.
Hosseinzadeh, Reza; Khorsandi, Khatereh
2017-06-01
The aim of current study was to use methylene blue-curcumin ion pair nanoparticles and single dyes as photosensitizer for comparison of photodynamic therapy (PDT) efficacy on MDA-MB-231 cancer cells, also various light sources effect on activation of photosensitizer (PS) was considered. Ion pair nanoparticles were synthesized using opposite charge ions precipitation and lyophilized. The PDT experiments were designed and the effect of PSs and light sources (Red LED (630nm; power density: 30mWcm -2 ) and blue LED (465nm; power density: 34mWcm -2 )) on the human breast cancer cell line were examined. The effect of PS concentration (0-75μg.mL -1 ), incubation time, irradiation time and light sources, and priority in irradiation of blue or red lights were determined. The results show that the ion pairing of methylene blue and curcumin enhance the photodynamic activity of both dyes and the cytotoxicity of ion pair nanoparticles on the MDA-231 breast cancer cell line. Blue and red LED light sources were used for photo activation of photosensitizers. The results demonstrated that both dyes can activate using red light LED better than blue light LED for singlet oxygen producing. Nano scale ion pair precipitating of methylene blue-curcumin enhanced the cell penetrating and subsequently cytotoxicity of both dyes together. Copyright © 2017 Elsevier B.V. All rights reserved.
Kinematics of red cell aspiration by fluorescence-imaged microdeformation.
Discher, D E; Mohandas, N
1996-10-01
Maps of fluorescing red cell membrane components on a pipette-aspirated projection are quantitated in an effort to elucidate and unify the heterogeneous kinematics of deformation. Transient gradients of diffusing fluorescent lipid first demonstrate the fluidity of an otherwise uniform-density bilayer and corroborate a "universal" calibration scale for relative surface density. A steep but smooth and stable gradient in the densities of the skeleton components spectrin, actin, and protein 4.1 is used to estimate large elastic strains along the aspirated skeleton. The deformation fields are argued to be an unhindered response to loading in the surface normal direction. Density maps intermediate to those of the compressible skeleton and fluid bilayer are exhibited by particular transmembrane proteins (e.g., Band 3) and yield estimates for the skeleton-connected fractions. Such connected proteins appear to occupy a significant proportion of the undeformed membrane surface and can lead to steric exclusion of unconnected integral membrane proteins from regions of network condensation. Consistent with membrane repatterning kinematics in reversible deformation, final vesiculation of the projection tip produces a cell fragment concentrated in freely diffusing proteins but depleted of skeleton.
1992-01-01
This study is concerned with the relationship between the Na/K/Cl cotransport system and the steady-state volume (MCV) of red blood cells. Cotransport rate was determined in unfractionated and density- separated red cells of different MCV from different donors to see whether cotransport differences contribute to the difference in the distribution of MCVs. Cotransport, studied in cells at their original MCVs, was determined as the bumetanide (10 microM)-sensitive 22Na efflux in the presence of ouabain (50 microM) after adjusting cellular Na (Nai) and Ki to achieve near maximal transport rates. This condition was chosen to rule out MCV-related differences in Nai and Ki that might contribute to differences in the net chemical driving force for cotransport. We found that in both unfractionated and density-separated red cells the cotransport rate was inversely correlated with MCV. MCV was correlated directly with red cell 2,3-diphosphoglycerate (DPG), whereas total red cell Mg was only slightly elevated in cells with high MCV. Thus intracellular free Mg (Mgifree) is evidently lower in red cells with high 2,3-DPG (i.e., high MCV) and vice versa. Results from flux measurements at their original MCVs, after altering Mgifree with the ionophore A23187, indicated a high Mgi sensitivity of cotransport: depletion of Mgifree inhibited and an elevation of Mgifree increased the cotransport rate. The apparent K0.5 for Mgifree was approximately 0.4 mM. Maximizing Mgifree at optimum Nai and Ki minimized the differences in cotransport rates among the different donors. It is concluded that the relative cotransport rate is regulated for cells in the steady state at their original cell volume, not by the number of copies of the cotransporter but by differences in Mgifree. The interindividual differences in Mgifree, determined primarily by differences in the 2,3-DPG content, are responsible for the differences in the relative cotransport activity that results in an inverse relationship with in vivo differences in MCV. Indirect evidence indicates that the relative cotransport rate, as indexed by Mgifree, is determined by the phosphorylated level of the cotransport system. PMID:1607852
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.
Ruan, Ping; Yong, Junguang; Shen, Hongtao; Zheng, Xianrong
2012-12-01
Multiple state-of-the-art techniques, such as multi-dimensional micro-imaging, fast multi-channel micro-spetrophotometry, and dynamic micro-imaging analysis, were used to dynamically investigate various effects of cell under the 900 MHz electromagnetic radiation. Cell changes in shape, size, and parameters of Hb absorption spectrum under different power density electromagnetic waves radiation were presented in this article. Experimental results indicated that the isolated human red blood cells (RBCs) do not have obviously real-time responses to the ultra-low density (15 μW/cm(2), 31 μW/cm(2)) electromagnetic wave radiation when the radiation time is not more than 30 min; however, the cells do have significant reactions in shape, size, and the like, to the electromagnetic waves radiation with power densities of 1 mW/cm(2) and 5 mW/cm(2). The data also reveal the possible influences and statistical relationships among living human cell functions, radiation amount, and exposure time with high-frequency electromagnetic waves. The results of this study may be significant on protection of human being and other living organisms against possible radiation affections of the high-frequency electromagnetic waves.
Kinetic and stoichiometric constraints determine the pathway of H2O2 consumption by red blood cells.
Orrico, Florencia; Möller, Matías N; Cassina, Adriana; Denicola, Ana; Thomson, Leonor
2018-05-09
Red blood cells (RBC) are considered as a circulating sink of H 2 O 2 , but a significant debate remains over the role of the different intraerythocyte peroxidases. Herein we examined the kinetic of decomposition of exogenous H 2 O 2 by human RBC at different cell densities, using fluorescent and oxymetric methods, contrasting the results against a mathematical model. Fluorescent measurements as well as oxygen production experiments showed that catalase was responsible for most of the decomposition of H 2 O 2 at cell densities suitable for both experimental settings (0.1-10 × 10 10 cell L -1 ), since sodium azide but not N-ethylmaleimide (NEM) inhibited H 2 O 2 consumption. Oxygen production decreased at high cell densities until none was detected above 1.1 × 10 12 cell L- 1 , being recovered after inhibition of the thiol dependent systems by NEM. This result underlined that the consumption of H 2 O 2 by catalase prevail at RBC densities regularly used for research, while the thiol dependent systems predominate when the cell density increases, approaching the normal number in blood (5 × 10 12 cell L- 1 ). The mathematical model successfully reproduced experimental results and at low cell number it showed a time sequence involving Prx as the first line of defense, followed by catalase, with a minor role by Gpx. The turning points were given by the total consumption of reduced Prx in first place and reduced GSH after that. However, Prx alone was able to account for the added H 2 O 2 (50µM) at physiological RBC density, calling attention to the importance of cell density in defining the pathway of H 2 O 2 consumption and offering an explanation to current apparently conflicting results in the literature. Copyright © 2018. Published by Elsevier Inc.
Influence of polar solvents on photovoltaic performance of Monascusred dye-sensitized solar cell
NASA Astrophysics Data System (ADS)
Lee, Jae Wook; Kim, Tae Young; Ko, Hyun Seok; Han, Shin; Lee, Suk-Ho; Park, Kyung Hee
Dye-sensitized solar cells (DSSCs) were assembled using natural dyes extracted from Monascus red pigment as a sensitizer. In this work, we studied the adsorption characteristics for harvesting sunlight and the electrochemical behavior for electron transfer in Monascus red DSSC using different solvents. The effect of polar aprotic and protic solvents including water, ethanol, and dimethylsulfoxide (DMSO) used in the sensitization process was investigated for the improvement in conversion efficiency of a cell. As for the Monascus red dye-sensitized electrode in DMSO solvent, the solar cell yields a short-circuit current density (Jsc) of 1.23 mA/cm2, a photovoltage (Voc) of 0.75 V, and a fill factor of 0.72, corresponding to an energy conversion efficiency (η) of 0.66%.
Kolodjaschna, Julia; Berisha, Fatmire; Lasta, Michael; Polska, Elzbieta; Fuchsjäger-Mayrl, Gabriele; Schmetterer, Leopold
2008-08-01
Administration of low doses of Escherichia coli endotoxin (LPS) to humans enables the study of inflammatory mechanisms. The purpose of the present study was to investigate the retinal vascular reactivity after LPS infusion. In a randomized placebo-controlled cross-over study, 18 healthy male volunteers received 20 IU/kg LPS or placebo as an intravenous bolus infusion. Outcome parameters were measured at baseline and 4h after LPS/placebo administration. At baseline and at 4h after administration a short period of 100% oxygen inhalation was used to assess retinal vasoreactivity to this stimulus. Perimacular white blood cell velocity, density and flux were assessed with the blue-field entoptic technique, retinal branch arterial and venous diameters were measured with a retinal vessel analyzer and red blood cell velocity in retinal branch veins was measured with laser Doppler velocimetry. LPS is associated with peripheral blood leukocytosis and increased white blood cell density in ocular microvessels (p<0.001). In addition, retinal arterial (p=0.02) and venous (p<0.01) diameters were increased. All retinal hemodynamic parameters showed a decrease during 100% oxygen breathing. This decrease was significantly blunted by LPS for all retinal outcome parameters except venous diameter (p=0.04 for white blood cell velocity, p=0.0002 for white blood cell density, p<0.0001 for white blood cell flux, p=0.01 for arterial diameter, p=0.02 for red blood cell velocity and p=0.006 for red blood cell flux). These data indicate that LPS-induced inflammation induces vascular dysregulation in the retina. This may provide a link between inflammation and vascular dysregulation. Further studies are warranted to investigate whether this model may be suitable to study inflammation induced vascular dysregulation in the eye.
Cellular biophysical markers of hydroxyurea treatment in sickle cell disease
NASA Astrophysics Data System (ADS)
So, Peter T. C.; Hosseini, Poorya; Abidi, Sabia Z.; Du, E.; Papageorgiou, Dimitrios P.; Park, YongKeun; Higgins, John; Kato, Gregory J.; Suresh, Subra; Dao, Ming; Yaqoob, Zahid
2017-04-01
Using a common-path interferometric technique, we measure biomechanical and morphological properties of individual red blood cells in SCD patients as a function of cell density, and investigate the correlation of these biophysical properties with drug intake as well as other clinically measured parameters.
Correlations between metabolic syndrome, serologic factors, and gallstones
Sang, Jae Hong; Ki, Nam Kyun; Cho, Jae Hwan; Ahn, Jae Ouk; Sunwoo, Jae Gun
2016-01-01
[Purpose] This study investigated the serologic factors associated with metabolic syndrome and gallstones. [Subjects and Methods] The study evaluated subjects who visited a health promotion center in Seoul from March 2, 2013 to February 28, 2014, and had undergone abdominal ultrasonography. Height, weight, and blood pressure were measured. Blood sampling was performed for high-density lipoprotein cholesterol, triglyceride, fasting blood glucose, total bilirubin, direct bilirubin, indirect bilirubin, aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, uric acid, total cholesterol, low-density lipoprotein cholesterol, thyroid stimulating hormone, and red and white blood cell counts. We conducted logistic regression analysis to assess the risk factors associated with metabolic syndrome. [Results] The risk factors for metabolic syndrome in men, in order of decreasing weight, were red blood cell count, body mass index, maximum size of gallstones, white blood cell count, waist circumference, and uric acid level. The factors in women, in order of decreasing weight, were red blood cell count, presence/absence of gallstones, uric acid level, body mass index, fasting blood glucose, and waist circumference. [Conclusion] Most serum biochemical factors and gallstone occurrence could be used to indicate the presence or absence of metabolic syndrome, independent of gender. PMID:27630427
Low density, resorcinol-formaldehyde aerogels
Pekala, R.W.
1988-05-26
The polycondensation of resorcinol with formaldehyde under alkaline conditions results in the formation of surface functionalized polymer ''clusters''. The covalent crosslinking of these ''clusters'' produces gels which when processed under supercritical conditions, produce low density, organic aerogels (density less than or equal to100 mg/cc; cell size less than or equal to0.1 microns). The aerogels are transparent,dark red in color and consist of interconnected colloidal-like particles with diameters of about 100 A/degree/. These aerogels may be further carbonized to form low density carbon foams with cell size of about 0.1 micron. 1 fig., 1 tab.
Influence of polar solvents on photovoltaic performance of Monascusred dye-sensitized solar cell.
Lee, Jae Wook; Kim, Tae Young; Ko, Hyun Seok; Han, Shin; Lee, Suk-Ho; Park, Kyung Hee
2014-05-21
Dye-sensitized solar cells (DSSCs) were assembled using natural dyes extracted from Monascus red pigment as a sensitizer. In this work, we studied the adsorption characteristics for harvesting sunlight and the electrochemical behavior for electron transfer in Monascus red DSSC using different solvents. The effect of polar aprotic and protic solvents including water, ethanol, and dimethylsulfoxide (DMSO) used in the sensitization process was investigated for the improvement in conversion efficiency of a cell. As for the Monascus red dye-sensitized electrode in DMSO solvent, the solar cell yields a short-circuit current density (Jsc) of 1.23mA/cm(2), a photovoltage (Voc) of 0.75V, and a fill factor of 0.72, corresponding to an energy conversion efficiency (η) of 0.66%. Copyright © 2014 Elsevier B.V. All rights reserved.
Sickle cell detection using a smartphone
Knowlton, S. M.; Sencan, I.; Aytar, Y.; Khoory, J.; Heeney, M. M.; Ghiran, I. C.; Tasoglu, S.
2015-01-01
Sickle cell disease affects 25% of people living in Central and West Africa and, if left undiagnosed, can cause life threatening “silent” strokes and lifelong damage. However, ubiquitous testing procedures have yet to be implemented in these areas, necessitating a simple, rapid, and accurate testing platform to diagnose sickle cell disease. Here, we present a label-free, sensitive, and specific testing platform using only a small blood sample (<1 μl) based on the higher density of sickle red blood cells under deoxygenated conditions. Testing is performed with a lightweight and compact 3D-printed attachment installed on a commercial smartphone. This attachment includes an LED to illuminate the sample, an optical lens to magnify the image, and two permanent magnets for magnetic levitation of red blood cells. The sample is suspended in a paramagnetic medium with sodium metabisulfite and loaded in a microcapillary tube that is inserted between the magnets. Red blood cells are levitated in the magnetic field based on equilibrium between the magnetic and buoyancy forces acting on the cells. Using this approach, we were able to distinguish between the levitation patterns of sickle versus control red blood cells based on their degree of confinement. PMID:26492382
Sickle cell detection using a smartphone.
Knowlton, S M; Sencan, I; Aytar, Y; Khoory, J; Heeney, M M; Ghiran, I C; Tasoglu, S
2015-10-22
Sickle cell disease affects 25% of people living in Central and West Africa and, if left undiagnosed, can cause life threatening "silent" strokes and lifelong damage. However, ubiquitous testing procedures have yet to be implemented in these areas, necessitating a simple, rapid, and accurate testing platform to diagnose sickle cell disease. Here, we present a label-free, sensitive, and specific testing platform using only a small blood sample (<1 μl) based on the higher density of sickle red blood cells under deoxygenated conditions. Testing is performed with a lightweight and compact 3D-printed attachment installed on a commercial smartphone. This attachment includes an LED to illuminate the sample, an optical lens to magnify the image, and two permanent magnets for magnetic levitation of red blood cells. The sample is suspended in a paramagnetic medium with sodium metabisulfite and loaded in a microcapillary tube that is inserted between the magnets. Red blood cells are levitated in the magnetic field based on equilibrium between the magnetic and buoyancy forces acting on the cells. Using this approach, we were able to distinguish between the levitation patterns of sickle versus control red blood cells based on their degree of confinement.
High throughput RNAi assay optimization using adherent cell cytometry.
Nabzdyk, Christoph S; Chun, Maggie; Pradhan, Leena; Logerfo, Frank W
2011-04-25
siRNA technology is a promising tool for gene therapy of vascular disease. Due to the multitude of reagents and cell types, RNAi experiment optimization can be time-consuming. In this study adherent cell cytometry was used to rapidly optimize siRNA transfection in human aortic vascular smooth muscle cells (AoSMC). AoSMC were seeded at a density of 3000-8000 cells/well of a 96 well plate. 24 hours later AoSMC were transfected with either non-targeting unlabeled siRNA (50 nM), or non-targeting labeled siRNA, siGLO Red (5 or 50 nM) using no transfection reagent, HiPerfect or Lipofectamine RNAiMax. For counting cells, Hoechst nuclei stain or Cell Tracker green were used. For data analysis an adherent cell cytometer, Celigo® was used. Data was normalized to the transfection reagent alone group and expressed as red pixel count/cell. After 24 hours, none of the transfection conditions led to cell loss. Red fluorescence counts were normalized to the AoSMC count. RNAiMax was more potent compared to HiPerfect or no transfection reagent at 5 nM siGLO Red (4.12 +/-1.04 vs. 0.70 +/-0.26 vs. 0.15 +/-0.13 red pixel/cell) and 50 nM siGLO Red (6.49 +/-1.81 vs. 2.52 +/-0.67 vs. 0.34 +/-0.19). Fluorescence expression results supported gene knockdown achieved by using MARCKS targeting siRNA in AoSMCs. This study underscores that RNAi delivery depends heavily on the choice of delivery method. Adherent cell cytometry can be used as a high throughput-screening tool for the optimization of RNAi assays. This technology can accelerate in vitro cell assays and thus save costs.
High throughput RNAi assay optimization using adherent cell cytometry
2011-01-01
Background siRNA technology is a promising tool for gene therapy of vascular disease. Due to the multitude of reagents and cell types, RNAi experiment optimization can be time-consuming. In this study adherent cell cytometry was used to rapidly optimize siRNA transfection in human aortic vascular smooth muscle cells (AoSMC). Methods AoSMC were seeded at a density of 3000-8000 cells/well of a 96well plate. 24 hours later AoSMC were transfected with either non-targeting unlabeled siRNA (50 nM), or non-targeting labeled siRNA, siGLO Red (5 or 50 nM) using no transfection reagent, HiPerfect or Lipofectamine RNAiMax. For counting cells, Hoechst nuclei stain or Cell Tracker green were used. For data analysis an adherent cell cytometer, Celigo® was used. Data was normalized to the transfection reagent alone group and expressed as red pixel count/cell. Results After 24 hours, none of the transfection conditions led to cell loss. Red fluorescence counts were normalized to the AoSMC count. RNAiMax was more potent compared to HiPerfect or no transfection reagent at 5 nM siGLO Red (4.12 +/-1.04 vs. 0.70 +/-0.26 vs. 0.15 +/-0.13 red pixel/cell) and 50 nM siGLO Red (6.49 +/-1.81 vs. 2.52 +/-0.67 vs. 0.34 +/-0.19). Fluorescence expression results supported gene knockdown achieved by using MARCKS targeting siRNA in AoSMCs. Conclusion This study underscores that RNAi delivery depends heavily on the choice of delivery method. Adherent cell cytometry can be used as a high throughput-screening tool for the optimization of RNAi assays. This technology can accelerate in vitro cell assays and thus save costs. PMID:21518450
A dinoflagellate Cochlodinium geminatum bloom in the Zhujiang (Pearl) River estuary in autumn 2009
NASA Astrophysics Data System (ADS)
Ke, Zhixin; Huang, Liangmin; Tan, Yehui; Song, Xingyu
2012-05-01
A severe Cochlodinium geminatum red tide (>300 km2) was observed in the Zhujiang (Pearl) River estuary, South China Sea in autumn 2009. We evaluated the environmental conditions and phytoplankton community structure during the outbreak. The red tide water mass had significantly higher dissolved inorganic phosphate (DIP), ammonia, and temperature, but significantly lower nitrite, nitrate, dissolved inorganic nitrogen (DIN), and DIN/DIP relative to the non-red-tide zones. The phytoplankton assemblage was dominated by dinoflagellates and diatoms during the red tide. C. geminatum was the most abundant species, with a peak density of 4.13×107 cell/L, accounting for >65% of the total phytoplankton density. The DIN/DIP ratio was the most important predictor of species, accounting for 12.45% of the total variation in the phytoplankton community. Heavy phosphorus loading, low precipitation, and severe saline intrusion were likely responsible for the bloom of C. geminatum.
Ortiz, O E; Lew, V L; Bookchin, R M
1990-08-01
1. Our findings of a low total magnesium content in the dense fraction (over 1.118 g ml-1) of sickle cell anaemia (SS) red cells seemed inconsistent with the low Mg2+ permeability and outward Mg2+ gradient seen in normal red cells, and prompted studies of the Mg2+ permeability and equilibria in the SS cells. 2. Deoxygenation and sickling induced Mg2+ permeabilization in SS cells, supporting non-specificity of the sickling-induced cation permeabilization, previously described for Na+, K+ and Ca2+. The extent of Mg2+ permeabilization was comparable in SS cells with normal or high density. 3. Compared with normal-density SS cells and normal red cells, the dense SS cells showed a much larger increase in the fraction of ionized magnesium ([Mg2+]i) on deoxygenation, resulting in [Mg2+]i levels sufficient to reverse the normal inward direction of the transmembrane Mg2+ gradient. 4. The molar ratio of 2,3-diphosphoglycerate (2,3-DPG) to haemoglobin was markedly reduced in the dense SS cells. Since 2,3-DPG and ATP are the main cytoplasmic Mg2+ buffers, their further reduction upon binding to deoxyhaemoglobin accounts for the high [Mg2+]i in the deoxygenated dense SS cells; the resulting outward electrochemical Mg2+ gradient, together with sickling-induced Mg2+ permeabilization, could explain the decreased total magnesium content of these cells. 5. The above findings suggested that the documented low sodium pump fluxes in dense SS cells may result from an increased Mg2+:ATP ratio, which is known to inhibit Na(+)-K+ exchange fluxes through the sodium pump. If so, deoxygenation, by increasing the Mg2+:ATP ratio, should inhibit the pump further, whereas increasing ATP should relieve the inhibition. Experiments designed to test this possibility showed that in these dense SS cells, the ouabain-sensitive K(86Rb) influx was low in oxygenated cells, was reduced further by deoxygenation, but was substantially increased after treatment with inosine, pyruvate and phosphate to increase their organic phosphate pool. These results were thus consistent with such a mechanism for Na+ pump inhibition in the dense SS cells.
Why Rudolph’s nose is red: observational study
van Kuijen, Anne-Marije; Milstein, Dan M J; Yürük, Koray; Folkow, Lars P; Fokkens, Wytske J; Blix, Arnoldus S
2012-01-01
Objective To characterise the functional morphology of the nasal microcirculation in humans in comparison with reindeer as a means of testing the hypothesis that the luminous red nose of Rudolph, one of the most well known reindeer pulling Santa Claus’s sleigh, is due to the presence of a highly dense and rich nasal microcirculation. Design Observational study. Setting Tromsø, Norway (near the North Pole), and Amsterdam, the Netherlands. Participants Five healthy human volunteers, two adult reindeer, and a patient with grade 3 nasal polyposis. Main outcome measures Architecture of the microvasculature of the nasal septal mucosa and head of the inferior turbinates, kinetics of red blood cells, and real time reactivity of the microcirculation to topical medicines. Results Similarities between human and reindeer nasal microcirculation were uncovered. Hairpin-like capillaries in the reindeers’ nasal septal mucosa were rich in red blood cells, with a perfused vessel density of 20 (SD 0.7) mm/mm2. Scattered crypt or gland-like structures surrounded by capillaries containing flowing red blood cells were found in human and reindeer noses. In a healthy volunteer, nasal microvascular reactivity was demonstrated by the application of a local anaesthetic with vasoconstrictor activity, which resulted in direct cessation of capillary blood flow. Abnormal microvasculature was observed in the patient with nasal polyposis. Conclusions The nasal microcirculation of reindeer is richly vascularised, with a vascular density 25% higher than that in humans. These results highlight the intrinsic physiological properties of Rudolph’s legendary luminous red nose, which help to protect it from freezing during sleigh rides and to regulate the temperature of the reindeer’s brain, factors essential for flying reindeer pulling Santa Claus’s sleigh under extreme temperatures. PMID:23247980
Cusick, Roland D; Hatzell, Marta; Zhang, Fang; Logan, Bruce E
2013-12-17
Power production from microbial reverse electrodialysis cell (MRC) electrodes is substantially improved compared to microbial fuel cells (MFCs) by using ammonium bicarbonate (AmB) solutions in multiple RED cell pair stacks and the cathode chamber. Reducing the number of RED membranes pairs while maintaining enhanced electrode performance could help to reduce capital costs. We show here that using only a single RED cell pair (CP), created by operating the cathode in concentrated AmB, dramatically increased power production normalized to cathode area from both acetate (Acetate: from 0.9 to 3.1 W/m(2)-cat) and wastewater (WW: 0.3 to 1.7 W/m(2)), by reducing solution and charge transfer resistances at the cathode. A second RED cell pair increased RED stack potential and reduced anode charge transfer resistance, further increasing power production (Acetate: 4.2 W/m(2); WW: 1.9 W/m(2)). By maintaining near optimal electrode power production with fewer membranes, power densities normalized to total membrane area for the 1-CP (Acetate: 3.1 W/m(2)-mem; WW: 1.7 W/m(2)) and 2-CP (Acetate: 1.3 W/m(2)-mem; WW: 0.6 W/m(2)) reactors were much higher than previous MRCs (0.3-0.5 W/m(2)-mem with acetate). While operating at peak power, the rate of wastewater COD removal, normalized to reactor volume, was 30-50 times higher in 1-CP and 2-CP MRCs than that in a single chamber MFC. These findings show that even a single cell pair AmB RED stack can significantly enhance electrical power production and wastewater treatment.
K(86Rb) transport heterogeneity in the low-density fraction of sickle cell anemia red blood cells.
Etzion, Z; Lew, V L; Bookchin, R M
1996-10-01
Previous studies have suggested ion transport heterogeneity among sickle cell anemia (SS) reticulocytes that could influence their dehydration susceptibility. We examined Ca2(+)-independent K transport in the lowest density (F1), reticulocyte-rich SS cells, measuring the effects of acidification, ouabain, and bumetanide on their unidirectional K(86Rb) fluxes. Unlike those of normal red blood cells and SS discocytes, the SS-F1 K(86Rb) fluxes were highly nonlinear, with large 5-min flux components (previously unobserved) and a more gradual decline over 60 min. Analysis revealed two distinct K pools: a rapid-turnover pool in a small fraction of cells, whose major ouabain-resistant K(86Rb) transport path showed distinctive properties including inhibition by high concentrations of bumetanide (> or = 1 mM) and stimulation at pH 7.0, and another heterogeneous, relatively slow-turnover pool, in most of the F1 cells, whose main ouabain-resistant K(86Rb) path was insensitive to bumetanide but was stimulated at pH 7.0, which is consistent with heterogeneous expression of the acid-sensitive K-Cl cotransport and with both rapid and slower generation of dehydrated SS cells.
Aleluia, Milena Magalhães; da Guarda, Caroline Conceição; Santiago, Rayra Pereira; Fonseca, Teresa Cristina Cardoso; Neves, Fábia Idalina; de Souza, Regiana Quinto; Farias, Larissa Alves; Pimenta, Felipe Araújo; Fiuza, Luciana Magalhães; Pitanga, Thassila Nogueira; Ferreira, Júnia Raquel Dutra; Adorno, Elisângela Vitória; Cerqueira, Bruno Antônio Veloso; Gonçalves, Marilda de Souza
2017-04-11
Sickle cell anemia (SCA) patients exhibit sub-phenotypes associated to hemolysis and vaso-occlusion. The disease has a chronic inflammatory nature that has been also associated to alterations in the lipid profile. This study aims to analyze hematological and biochemical parameters to provide knowledge about the SCA sub-phenotypes previously described and suggest a dyslipidemic sub-phenotype. A cross-sectional study was conducted from 2013 to 2014, and 99 SCA patients in steady state were enrolled. We assessed correlations and associations with hematological and biochemical data and investigated the co-inheritance of -α 3.7Kb -thalassemia (-α 3.7Kb -thal). Correlation analyses were performed using Spearman and Pearson coefficient. The median of quantitative variables between two groups was compared using t-test and Mann-Whitney. P-values <0.05 were considered statistically significant. We found significant association of high lactate dehydrogenase levels with decreased red blood cell count and hematocrit as well as high levels of total and indirect bilirubin. SCA patients with low nitric oxide metabolites had high total cholesterol, high-density lipoprotein cholesterol, and low-density lipoprotein cholesterol and reduced very low-density cholesterol, triglycerides, direct bilirubin level and reticulocyte counts. In SCA patients with high-density lipoprotein cholesterol greater than 40 mg/dL, we observed increased red blood cell count, hemoglobin, hematocrit, and fetal hemoglobin and decreased nitric oxide metabolites levels. The presence of -α 3.7Kb -thal was associated with high red blood cell count and low mean corpuscular volume, mean corpuscular hemoglobin, platelet count and total and indirect bilirubin levels. Our results provide additional information about the association between biomarkers and co-inheritance of -α 3.7Kb -thal in SCA, and suggest the role of dyslipidemia and nitric oxide metabolites in the characterization of this sub-phenotype.
Shape-Shifted Red Blood Cells: A Novel Red Blood Cell Stage?
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
Shape-Shifted Red Blood Cells: A Novel Red Blood Cell Stage?
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.
Kinematics of red cell aspiration by fluorescence-imaged microdeformation.
Discher, D E; Mohandas, N
1996-01-01
Maps of fluorescing red cell membrane components on a pipette-aspirated projection are quantitated in an effort to elucidate and unify the heterogeneous kinematics of deformation. Transient gradients of diffusing fluorescent lipid first demonstrate the fluidity of an otherwise uniform-density bilayer and corroborate a "universal" calibration scale for relative surface density. A steep but smooth and stable gradient in the densities of the skeleton components spectrin, actin, and protein 4.1 is used to estimate large elastic strains along the aspirated skeleton. The deformation fields are argued to be an unhindered response to loading in the surface normal direction. Density maps intermediate to those of the compressible skeleton and fluid bilayer are exhibited by particular transmembrane proteins (e.g., Band 3) and yield estimates for the skeleton-connected fractions. Such connected proteins appear to occupy a significant proportion of the undeformed membrane surface and can lead to steric exclusion of unconnected integral membrane proteins from regions of network condensation. Consistent with membrane repatterning kinematics in reversible deformation, final vesiculation of the projection tip produces a cell fragment concentrated in freely diffusing proteins but depleted of skeleton. Images FIGURE 1 FIGURE 2 FIGURE 4 FIGURE 5 FIGURE 7 FIGURE 8 FIGURE 9 FIGURE 10 FIGURE 11 PMID:8889146
Simulations of molecular diffusion in lattices of cells: insights for NMR of red blood cells.
Regan, David G; Kuchel, Philip W
2002-01-01
The pulsed field-gradient spin-echo (PGSE) nuclear magnetic resonance (NMR) experiment, conducted on a suspension of red blood cells (RBC) in a strong magnetic field yields a q-space plot consisting of a series of maxima and minima. This is mathematically analogous to a classical optical diffraction pattern. The method provides a noninvasive and novel means of characterizing cell suspensions that is sensitive to changes in cell shape and packing density. The positions of the features in a q-space plot characterize the rate of exchange across the membrane, cell dimensions, and packing density. A diffusion tensor, containing information regarding the diffusion anisotropy of the system, can also be derived from the PGSE NMR data. In this study, we carried out Monte Carlo simulations of diffusion in suspensions of "virtual" cells that had either biconcave disc (as in RBC) or oblate spheroid geometry. The simulations were performed in a PGSE NMR context thus enabling predictions of q-space and diffusion tensor data. The simulated data were compared with those from real PGSE NMR diffusion experiments on RBC suspensions that had a range of hematocrit values. Methods that facilitate the processing of q-space data were also developed. PMID:12080109
Simulations of molecular diffusion in lattices of cells: insights for NMR of red blood cells.
Regan, David G; Kuchel, Philip W
2002-07-01
The pulsed field-gradient spin-echo (PGSE) nuclear magnetic resonance (NMR) experiment, conducted on a suspension of red blood cells (RBC) in a strong magnetic field yields a q-space plot consisting of a series of maxima and minima. This is mathematically analogous to a classical optical diffraction pattern. The method provides a noninvasive and novel means of characterizing cell suspensions that is sensitive to changes in cell shape and packing density. The positions of the features in a q-space plot characterize the rate of exchange across the membrane, cell dimensions, and packing density. A diffusion tensor, containing information regarding the diffusion anisotropy of the system, can also be derived from the PGSE NMR data. In this study, we carried out Monte Carlo simulations of diffusion in suspensions of "virtual" cells that had either biconcave disc (as in RBC) or oblate spheroid geometry. The simulations were performed in a PGSE NMR context thus enabling predictions of q-space and diffusion tensor data. The simulated data were compared with those from real PGSE NMR diffusion experiments on RBC suspensions that had a range of hematocrit values. Methods that facilitate the processing of q-space data were also developed.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhang, Lei; Cole, Jacqueline M.
2014-02-18
The optical and electronic properties of a TiO2 nanoparticle-assisted photo-isomerizable surface, prepared by an azo dye/TiO2 nanocomposite film, are examined experimentally and computationally. The azo dye, para-methyl red, undergoes photoisomerization at room temperature, catalyzed by the TiO2 nanoparticle supports, while it exhibits negligible photoisomerization in solvents under otherwise identical conditions. Density functional theory and time-dependent density functional theory are employed to explain the origin of this photoisomerization in these dye…TiO2 nanoparticle self-assembled monolayers (SAMs). The device performance of these SAMs when embedded into dye-sensitized solar cells is used to further elucidate the nature of this azo dye photoisomerization and relatemore » it to the ensuing optoelectronic properties.« less
Stroncek, David F; Fellowes, Vicki; Pham, Chauha; Khuu, Hanh; Fowler, Daniel H; Wood, Lauren V; Sabatino, Marianna
2014-09-17
Peripheral blood mononuclear cells (PBMC) concentrates collected by apheresis are frequently used as starting material for cellular therapies, but the cell of interest must often be isolated prior to initiating manufacturing. The results of enriching 59 clinical PBMC concentrates for monocytes or lymphocytes from patients with solid tumors or multiple myeloma using a commercial closed system semi-automated counter-flow elutriation instrument (Elutra, Terumo BCT) were evaluated for quality and consistency. Elutriated monocytes (n = 35) were used to manufacture autologous dendritic cells and elutriated lymphocytes (n = 24) were used manufacture autologous T cell therapies. Elutriated monocytes with >10% neutrophils were subjected to density gradient sedimentation to reduce neutrophil contamination and elutriated lymphocytes to RBC lysis. Elutriation separated the PBMC concentrates into 5 fractions. Almost all of the lymphocytes, platelets and red cells were found in fractions 1 and 2; in contrast, most of the monocytes, 88.6 ± 43.0%, and neutrophils, 74.8 ± 64.3%, were in fraction 5. In addition, elutriation of 6 PBMCs resulted in relatively large quantities of monocytes in fractions 1 or 2. These 6 PBMCs contained greater quantities of monocytes than the other 53 PBMCs. Among fraction 5 isolates 38 of 59 contained >10% neutrophils. High neutrophil content of fraction 5 was associated with greater quantities of neutrophils in the PBMC concentrate. Following density gradient separation the neutrophil counts fell to 3.6 ± 3.4% (all products contained <10% neutrophils). Following red cell lysis of the elutriated lymphocyte fraction the lymphocyte recovery was 86.7 ± 24.0% and 34.3 ± 37.4% of red blood cells remained. Elutriation was consistent and effective for isolating monocytes and lymphocytes from PBMC concentrates for manufacturing clinical cell therapies, but further processing is often required.
Schwartz, R S; Musto, S; Fabry, M E; Nagel, R L
1998-12-15
In sickle cell anemia (SS), some red blood cells dehydrate, forming a hyperdense (HD) cell fraction (>1.114 g/mL; mean corpuscular hemoglobin concentration [MCHC], >46 g/dL) that contains many irreversibly sickled cells (ISCs), whereas other SS red blood cells dehydrate to an intermediate density (ID; 1.090 to 1.114 g/mL; MCHC, 36 to 46 g/dL). This study asks if the potassium-chloride cotransporter (K:Cl) and the calcium-dependent potassium channel [K(Ca2+)] are participants in the formation of one or both types of dense SS red blood cells. We induced sickling by exposing normal density (ND; 1.080 to 1.090 g/mL; MCHC, 32 to 36 g/dL) SS discocytes to repetitive oxygenation-deoxygenation (O-D) cycles in vitro. At physiologic Na+, K+, and Cl-, and 0.5 to 2 mmol/L Ca2+, the appearance of dense cells was time- and pH-dependent. O-D cycling at pH 7.4 in 5% CO2-equilibrated buffer generated only ID cells, whereas O-D cycling at pH 6.8 in 5% CO2-equilibrated buffer generated both ID and HD cells, the latter taking more than 8 hours to form. At 22 hours, 35% +/- 17% of the parent ND cells were recovered in the ID fraction and 18% +/- 11% in the HD fraction. Continuous deoxygenation (N2/5% CO2) at pH 6.8 generated both ID and HD cells, but many of these cells had multiple projections, clearly different from the morphology of endogenous dense cells and ISCs. Continuous oxygenation (air/5% CO2) at pH 6.8 resulted in less than 10% dense cell (ID + HD) formation. ATP depletion substantially increased HD cell formation and moderately decreased ID cell formation. HD cells formed after 22 hours of O-D cycling at pH 6.8 contained fewer F cells than did ID cells, suggesting that HD cell formation is particularly dependent on HbS polymerization. EGTA chelation of buffer Ca2+ inhibited HD but not ID cell formation, and increasing buffer Ca2+ from 0.5 to 2 mmol/L promoted HD but not ID cell formation in some SS patients. Substitution of nitrate for Cl- inhibited ID cell formation, as did inhibitors of the K:Cl cotransporter, okadaic acid, and [(dihydroindenyl) oxy]alkanoic acid (DIOA). Conversely, inhibitors of K(Ca2+), charybdotoxin and clotrimazole, inhibited HD cell formation. The combined use of K(Ca2+) and K:Cl inhibitors nearly eliminated dense cell (ID + HD cell) formation. In summary, dense cells formed by O-D cycling for 22 hours at pH 7.4 cycling are predominately the ID type, whereas dense cells formed by O-D cycling for 22 hours at pH 6.8 are both the ID and HD type, with the latter low in HbF, suggesting that HD cell formation has a greater dependency on HbS polymerization. A combination of K:Cl cotransport and the K(Ca2+) activities account for the majority of dense cells formed, and these pathways can be driven independently. We propose a model in which reversible sickling-induced K+ loss by K:Cl primarily generates ID cells and K+ loss by the K(Ca2+) channel primarily generates HD cells. These results imply that both pathways must be inhibited to completely prevent dense SS cell formation and have potential therapeutic implications.
Age Decline in the Activity of the Ca2+-sensitive K+ Channel of Human Red Blood Cells
Tiffert, Teresa; Daw, Nuala; Etzion, Zipora; Bookchin, Robert M.; Lew, Virgilio L.
2007-01-01
The Ca2+-sensitive K+ channel of human red blood cells (RBCs) (Gardos channel, hIK1, hSK4) was implicated in the progressive densification of RBCs during normal senescence and in the mechanism of sickle cell dehydration. Saturating RBC Ca2+ loads were shown before to induce rapid and homogeneous dehydration, suggesting that Gardos channel capacity was uniform among the RBCs, regardless of age. Using glycated hemoglobin as a reliable RBC age marker, we investigated the age–activity relation of Gardos channels by measuring the mean age of RBC subpopulations exceeding a set high density boundary during dehydration. When K+ permeabilization was induced with valinomycin, the oldest and densest cells, which started nearest to the set density boundary, crossed it first, reflecting conservation of the normal age–density distribution pattern during dehydration. However, when Ca2+ loads were used to induce maximal K+ fluxes via Gardos channels in all RBCs (F max), the youngest RBCs passed the boundary first, ahead of the older RBCs, indicating that Gardos channel F max was highest in those young RBCs, and that the previously observed appearance of uniform dehydration concealed a substantial degree of age scrambling during the dehydration process. Further analysis of the Gardos channel age–activity relation revealed a monotonic decline in F max with cell age, with a broad quasi-Gaussian F max distribution among the RBCs. PMID:17470662
Age decline in the activity of the Ca2+-sensitive K+ channel of human red blood cells.
Tiffert, Teresa; Daw, Nuala; Etzion, Zipora; Bookchin, Robert M; Lew, Virgilio L
2007-05-01
The Ca(2+)-sensitive K(+) channel of human red blood cells (RBCs) (Gardos channel, hIK1, hSK4) was implicated in the progressive densification of RBCs during normal senescence and in the mechanism of sickle cell dehydration. Saturating RBC Ca(2+) loads were shown before to induce rapid and homogeneous dehydration, suggesting that Gardos channel capacity was uniform among the RBCs, regardless of age. Using glycated hemoglobin as a reliable RBC age marker, we investigated the age-activity relation of Gardos channels by measuring the mean age of RBC subpopulations exceeding a set high density boundary during dehydration. When K(+) permeabilization was induced with valinomycin, the oldest and densest cells, which started nearest to the set density boundary, crossed it first, reflecting conservation of the normal age-density distribution pattern during dehydration. However, when Ca(2+) loads were used to induce maximal K(+) fluxes via Gardos channels in all RBCs (F(max)), the youngest RBCs passed the boundary first, ahead of the older RBCs, indicating that Gardos channel F(max) was highest in those young RBCs, and that the previously observed appearance of uniform dehydration concealed a substantial degree of age scrambling during the dehydration process. Further analysis of the Gardos channel age-activity relation revealed a monotonic decline in F(max) with cell age, with a broad quasi-Gaussian F(max) distribution among the RBCs.
Effect of leg exercise training on vascular volumes during 30 days of 6 deg head-down bed rest
NASA Technical Reports Server (NTRS)
Greenleaf, J. E.; Vernikos, J.; Wade, C. E.; Barnes, P. R.
1992-01-01
In order to investigate the effects of leg exercise training on vascular volumes during 30 d of 6-deg head-down bed rest, plasma and red cell volumes, body density, and water balance were measured in 19 men confined to bed rest (BR). One group had no exercise training (NOE), another near-maximal variable-intensity isotonic exercise (ITE) for 60 min/d, and the third near-maximal intermittent isokinetic exercise (IKE) for 60 min/d. Mean energy costs for the NOE, IKE, and ITE regimens were determined. Body densities within groups and mean urine volumes between groups were unchanged during BR. Changes in red cell volume followed changes in plasma volume. There was close coupling between resting plasma volume and plasma protein and osmotic content. It is argued that the ITE training protocol is better than the IKE protocol for maintaining plasma volume during prolonged exposure to BR.
Cloned Hemoglobin Genes Enhance Growth Of Cells
NASA Technical Reports Server (NTRS)
Khosla, Chaitan; Bailey, James E.
1991-01-01
Experiments show that portable deoxyribonucleic acid (DNA) sequences incorporated into host cells make them produce hemoglobins - oxygen-binding proteins essential to function of red blood cells. Method useful in several biotechnological applications. One, enhancement of growth of cells at higher densities. Another, production of hemoglobin to enhance supplies of oxygen in cells, for use in chemical reactions requiring oxygen, as additive to serum to increase transport of oxygen, and for binding and separating oxygen from mixtures of gases.
Seasonality and toxin production of Pyrodinium bahamense in a Red Sea lagoon.
Banguera-Hinestroza, E; Eikrem, W; Mansour, H; Solberg, I; Cúrdia, J; Holtermann, K; Edvardsen, B; Kaartvedt, S
2016-05-01
Harmful algal blooms of the dinoflagellate Pyrodinium bahamense have caused human and economic losses in the last decades. This study, for the first time, documents a bloom of P. bahamense in the Red Sea. The alga was recurrently present in a semi-enclosed lagoon throughout nearly 2 years of observations. The highest cell densities (10 4 -10 5 cellsL -1 ) were recorded from September to beginning of December at temperatures and salinities of ∼26-32°C and ∼41, respectively. The peak of the bloom was recorded mid-November, before a sharp decrease in cell numbers at the end of December. Minimum concentrations in summer were at ∼10 3 cellsL -1 . A saxitoxin ELISA immunoassay of cultures and water samples confirmed the toxicity of the strain found in the Red Sea. Moreover, a gene expression analysis of the saxitoxin gene domain SxtA4 showed that transcript production peaked at the culmination of the bloom, suggesting a relation between transcript production, sudden cells increment-decline, and environmental factors. Copyright © 2016 Elsevier B.V. All rights reserved.
Cost-effective and Rapid Blood Analysis on a Cell-phone
Zhu, Hongying; Sencan, Ikbal; Wong, Justin; Dimitrov, Stoyan; Tseng, Derek; Nagashima, Keita; Ozcan, Aydogan
2013-01-01
We demonstrate a compact and cost-effective imaging cytometry platform installed on a cell-phone for the measurement of the density of red and white blood cells as well as hemoglobin concentration in human blood samples. Fluorescent and bright-field images of blood samples are captured using separate optical attachments to the cell-phone and are rapidly processed through a custom-developed smart application running on the phone for counting of blood cells and determining hemoglobin density. We evaluated the performance of this cell-phone based blood analysis platform using anonymous human blood samples and achieved comparable results to a standard bench-top hematology analyser. Test results can either be stored on the cell-phone memory or be transmitted to a central server, providing remote diagnosis opportunities even in field settings. PMID:23392286
Cost-effective and rapid blood analysis on a cell-phone.
Zhu, Hongying; Sencan, Ikbal; Wong, Justin; Dimitrov, Stoyan; Tseng, Derek; Nagashima, Keita; Ozcan, Aydogan
2013-04-07
We demonstrate a compact and cost-effective imaging cytometry platform installed on a cell-phone for the measurement of the density of red and white blood cells as well as hemoglobin concentration in human blood samples. Fluorescent and bright-field images of blood samples are captured using separate optical attachments to the cell-phone and are rapidly processed through a custom-developed smart application running on the phone for counting of blood cells and determining hemoglobin density. We evaluated the performance of this cell-phone based blood analysis platform using anonymous human blood samples and achieved comparable results to a standard bench-top hematology analyser. Test results can either be stored on the cell-phone memory or be transmitted to a central server, providing remote diagnosis opportunities even in field settings.
Human red blood cell aging at 5,050-m altitude: a role during adaptation to hypoxia.
Samaja, M; Brenna, L; Allibardi, S; Cerretelli, P
1993-10-01
To test the hypothesis that the human red blood cell aging process participates actively in the adaptation to hypoxia, we studied some physical and biochemical hematologic variables in 10 volunteers at sea level (SL) and after 1 (1WK) or 5 wk (5WK) of exposure to 5,050-m altitude. The 2,3-diphosphoglycerate-to-hemoglobin ratio (2,3-DPG/Hb) was 0.88 +/- 0.03 (mol/mol) at SL and increased to 1.08 +/- 0.03 (P = 0.002) and 1.28 +/- 0.05 (P < 0.0001) at 1WK and 5WK, respectively. The average red blood cell density (D50), which is inversely proportional to the fraction of young red blood cells and is therefore an index of the red blood cell aging process, was 1.1053 +/- 0.0007 g/ml at SL and decreased to 1.1046 +/- 0.0008 g/ml (NS) and 1.1018 +/- 0.0008 g/ml (P < 0.001) at 1WK and 5WK, respectively. D50 was correlated with 2,3-DPG/Hb at SL (P = 0.004), only weakly at 5WK (P = 0.1), but not at all at 1WK. The arterial O2 saturation was correlated with the change of 2,3-DPG/Hb in 1WK (P = 0.02) and that of D50 in 5WK (P = 0.04). It is concluded that short-term (1WK) increase of 2,3-DPG/Hb is not associated with the erythropoietic response but is presumably due to respiratory alkalosis. By contrast, after prolonged hypoxia (5WK), erythropoiesis may provide an efficient way for increasing blood 2,3-DPG through an augmented proportion of young red blood cells.
Three-Dimensional Simulation of Ultrasound-Induced Microalgal Cell Disruption.
Wang, M; Yuan, W; Hale, Andy
2016-03-01
The three-dimensional distribution (x, y, and z) of ultrasound-induced microalgal cell disruption in a sonochemical reactor was predicted by solving the Helmholtz equation using a three-dimensional acoustic module in the COMSOL Multiphysics software. The simulated local ultrasound pressure at any given location (x, y, and z) was found to correlate with cell disruption of a freshwater alga, Scenedesmus dimorphus, represented by the change of algal cell particle/debris concentration, chlorophyll-a fluorescence density (CAFD), and Nile red stained lipid fluorescence density (LFD), which was also validated by the model reaction of potassium iodide oxidation (the Weissler reaction). Furthermore, the effect of ultrasound power intensity and processing duration on algal cell disruption was examined to address the limitation of the model.
Oxidation-induced calcium-dependent dehydration of normal human red blood cells.
Shcherbachenko, Irina M; Lisovskaya, Irina L; Tikhonov, Vladimir P
2007-05-01
Phenazine-methosulphate (PMS) is a strong oxidant that induces reactive oxygen species (ROS) formation in cells. Though it has been shown that PMS increases the red blood cell (RBC) membrane permeability to K(+), the hypotheses on the mechanism of PMS-induced effects are contradictory and there are no data on volume changes induced by this oxidant. Therefore, the influence of the PMS + ascorbate oxidative system on the volume of normal human RBCs was studied. In a Ca(2 + )-containing medium, PMS + ascorbate caused dehydration (shrinking) of RBCs judged by: (1) changes in the density and osmotic resistance distributions of RBCs, and (2) a decrease in their low-angle scattering assessed by FACS analysis. The dehydration resulted from activation of the Gardos channels, was PMS and ascorbate concentration-dependent, was associated with broadening of the density and osmotic resistance distributions of the RBCs, and decreased in the presence of the taxifolin and rutin antioxidants. These findings contribute to a better understanding of the physiology and pathology of oxidatively-modified RBCs and may be of practical significance in estimating the antioxidant activity of various substances.
Biochemical and hematologic changes after short-term space flight
NASA Technical Reports Server (NTRS)
Leach, C. S.
1992-01-01
Clinical laboratory data from blood samples obtained from astronauts before and after 28 flights (average duration = 6 days) of the Space Shuttle were analyzed by the paired t-test and the Wilcoxon signed-rank test and compared with data from the Skylab flights (duration approximately 28, 59, and 84 days). Angiotensin I and aldosterone were elevated immediately after short-term space flights, but the response of angiotensin I was delayed after Skylab flights. Serum calcium was not elevated after Shuttle flights, but magnesium and uric acid decreased after both Shuttle and Skylab. Creatine phosphokinase in serum was reduced after Shuttle but not Skylab flights, probably because exercises to prevent deconditioning were not performed on the Shuttle. Total cholesterol was unchanged after Shuttle flights, but low density lipoprotein cholesterol increased and high density lipoprotein cholesterol decreased. The concentration of red blood cells was elevated after Shuttle flights and reduced after Skylab flights. Reticulocyte count was decreased after both short- and long-term flights, indicating that a reduction in red blood cell mass is probably more closely related to suppression of red cell production than to an increase in destruction of erythrocytes. Serum ferritin and number of platelets were also elevated after Shuttle flights. In determining the reasons for postflight differences between the shorter and longer flights, it is important to consider not only duration but also countermeasures, differences between spacecraft, and procedures for landing and egress.
Mapping the distribution of specific antibody interaction forces on individual red blood cells
NASA Astrophysics Data System (ADS)
Yeow, Natasha; Tabor, Rico F.; Garnier, Gil
2017-02-01
Current blood typing methods rely on the agglutination of red blood cells (RBCs) to macroscopically indicate a positive result. An indirect agglutination mechanism is required when blood typing with IgG forms of antibodies. To date, the interaction forces between anti-IgG and IgG antibodies have been poorly quantified, and blood group related antigens have never been quantified with the atomic force microscope (AFM). Instead, the total intensity resulting from fluorescent-tagged antibodies adsorbed on RBC has been measured to calculate an average antigen density on a series of RBCs. In this study we mapped specific antibody interaction forces on the RBC surface. AFM cantilever tips functionalized with anti-IgG were used to probe RBCs incubated with specific IgG antibodies. This work provides unique insight into antibody-antigen interactions in their native cell-bound location, and crucially, on a per-cell basis rather than an ensemble average set of properties. Force profiles obtained from the AFM directly provide not only the anti-IgG - IgG antibody interaction force, but also the spatial distribution and density of antigens over a single cell. This new understanding might be translated into the development of very selective and quantitative interactions that underpin the action of drugs in the treatment of frontier illnesses.
NASA Astrophysics Data System (ADS)
Aykol, Muratahan; Doak, Jeff W.; Wolverton, C.
2017-06-01
We evaluate the energetic stabilities of white, red, and black allotropes of phosphorus using density functional theory (DFT) and hybrid functional methods, van der Waals (vdW) corrections (DFT+vdW and hybrid+vdW), vdW density functionals, and random phase approximation (RPA). We find that stability of black phosphorus over red-V (i.e., the violet form) is not ubiquitous among these methods, and the calculated enthalpies for the reaction phosphorus (red-V)→phosphorus (black) are scattered between -20 and 40 meV/atom. With local density and generalized gradient approximations, and hybrid functionals, mean absolute errors (MAEs) in densities of P allotropes relative to experiments are found to be around 10%-25%, whereas with vdW-inclusive methods, MAEs in densities drop below ˜5 %. While the inconsistency among the density functional methods could not shed light on the stability puzzle of black versus red phosphorus, comparison of their accuracy in predicting densities and the supplementary RPA results on relative stabilities indicate that opposite to the common belief, black and red phosphorus are almost degenerate, or the red-V (violet) form of phosphorus might even be the ground state.
Rapid separation of bacteria from blood — Chemical aspects
Alizadeh, Mahsa; Wood, Ryan L.; Buchanan, Clara M.; Bledsoe, Colin G.; Wood, Madison E.; McClellan, Daniel S.; Blanco, Rae; Ravsten, Tanner V.; Husseini, Ghaleb A.; Hickey, Caroline L.; Robison, Richard A.; Pitt, William G.
2017-01-01
To rapidly diagnose infectious organisms causing blood sepsis, bacteria must be rapidly separated from blood, a very difficult process considering that concentrations of bacteria are many orders of magnitude lower than concentrations of blood cells. We have successfully separated bacteria from red and white blood cells using a sedimentation process in which the separation is driven by differences in density and size. Seven mL of whole human blood spiked with bacteria is placed in a 12-cm hollow disk and spun at 3000 rpm for 1 min. The red and white cells sediment more than 30-fold faster than bacteria, leaving much of the bacteria in the plasma. When the disk is slowly decelerated, the plasma flows to a collection site and the red and white cells are trapped in the disk. Analysis of the recovered plasma shows that about 36% of the bacteria is recovered in the plasma. The plasma is not perfectly clear of red blood cells, but about 94% have been removed. This paper describes the effects of various chemical aspects of this process, including the influence of anticoagulant chemistry on the separation efficiency and the use of wetting agents and platelet aggregators that may influence the bacterial recovery. In a clinical scenario, the recovered bacteria can be subsequently analyzed to determine their species and resistance to various antibiotics. PMID:28365426
Red Light Represses the Photophysiology of the Scleractinian Coral Stylophora pistillata
Wijgerde, Tim; van Melis, Anne; Silva, Catarina I. F.; Leal, Miguel C.; Vogels, Luc; Mutter, Claudia; Osinga, Ronald
2014-01-01
Light spectrum plays a key role in the biology of symbiotic corals, with blue light resulting in higher coral growth, zooxanthellae density, chlorophyll a content and photosynthesis rates as compared to red light. However, it is still unclear whether these physiological processes are blue-enhanced or red-repressed. This study investigated the individual and combined effects of blue and red light on the health, zooxanthellae density, photophysiology and colouration of the scleractinian coral Stylophora pistillata over 6 weeks. Coral fragments were exposed to blue, red, and combined 50/50% blue red light, at two irradiance levels (128 and 256 μmol m−2 s−1). Light spectrum affected the health/survival, zooxanthellae density, and NDVI (a proxy for chlorophyll a content) of S. pistillata. Blue light resulted in highest survival rates, whereas red light resulted in low survival at 256 μmol m−2 s−1. Blue light also resulted in higher zooxanthellae densities compared to red light at 256 μmol m−2 s−1, and a higher NDVI compared to red and combined blue red light. Overall, our results suggest that red light negatively affects the health, survival, symbiont density and NDVI of S. pistillata, with a dominance of red over blue light for NDVI. PMID:24658108
Red light represses the photophysiology of the scleractinian coral Stylophora pistillata.
Wijgerde, Tim; van Melis, Anne; Silva, Catarina I F; Leal, Miguel C; Vogels, Luc; Mutter, Claudia; Osinga, Ronald
2014-01-01
Light spectrum plays a key role in the biology of symbiotic corals, with blue light resulting in higher coral growth, zooxanthellae density, chlorophyll a content and photosynthesis rates as compared to red light. However, it is still unclear whether these physiological processes are blue-enhanced or red-repressed. This study investigated the individual and combined effects of blue and red light on the health, zooxanthellae density, photophysiology and colouration of the scleractinian coral Stylophora pistillata over 6 weeks. Coral fragments were exposed to blue, red, and combined 50/50% blue red light, at two irradiance levels (128 and 256 μmol m(-2) s(-1)). Light spectrum affected the health/survival, zooxanthellae density, and NDVI (a proxy for chlorophyll a content) of S. pistillata. Blue light resulted in highest survival rates, whereas red light resulted in low survival at 256 μmol m(-2) s(-1). Blue light also resulted in higher zooxanthellae densities compared to red light at 256 μmol m(-2) s(-1), and a higher NDVI compared to red and combined blue red light. Overall, our results suggest that red light negatively affects the health, survival, symbiont density and NDVI of S. pistillata, with a dominance of red over blue light for NDVI.
Durpès, Marie-Claude; Nebor, Danitza; du Mesnil, Pierre Couespel; Mougenel, Danièle; Decastel, Monique; Elion, Jacques; Hardy-Dessources, Marie-Dominique
2010-04-15
We investigated the effects of the chemokines IL-8 and RANTES on the activity of the Gardos channel (GC) of sickle red blood cells (SSRBCs). SSRBCs expressing the Duffy antigen receptor for chemokines (DARC) incubated under oxygenated conditions exhibit GC activation. The deoxygenation-stimulated K(+) loss via the GC is activated by the chemokines in the Duffy-positive SSRBCs. The percentage of cells with high density is 17 times higher in the Duffy-positive group. These findings are consistent with a greater susceptibility of Duffy-positive SSRBCs to inflammatory chemokines leading to GC activation and cellular dehydration and suggest a coupling, promoted by the sickling process, between DARC and the GC.
NASA Astrophysics Data System (ADS)
Pradana, Dimas Adhi; Pondawinata, Marizki; Widyarini, Sitarina
2017-03-01
This study aimed to determine the potential activity of standardized ethanolic extract of red spinach as prevention against atherosclerosis based on the level of Low-Density Lipoprotein (LDL) and histopathological feature of aorta in male Sprague-Dawley rats induced by high-fat, high-cholesterol diet. A total of 42 animals was divided into 6 groups: normal control group, negative control group, positive control group (0.9 mg/kgBW of simvastatin), first intervention group (200 mg/kgBW of red spinach extract), second intervention group (400 mg/kgBW of red spinach extract), and third intervention group (800 mg/kgBW of red spinach extract). From the first day up to the 66th day, all the groups, except the normal control group and negative control group, were administered simvastatin (positive control) and extract of amaranth (intervention). Then, from the eighth day until Day 66, induction of high-fat and high-cholesterol diet was given in two hours after the simvastatin and red spinach extract administration. The determination of LDL parameters was conducted on Day 0, Day 35, and Day 67. On the 67th day, the animals were dissected to examine the aortic histopathological parameters. The results showed that the ethanolic extract of red spinach with a dose of 200 mg/kgBW, 400 mg/kgBW, and 800 mg/kgBW statistically demonstrated a significant difference (p<0.05). The histopathological feature of the aorta in the treatment indicated the absence of fat in the blood vessel walls or even of foam cells supporting thereby the result of LDL level. This means there was a significant effect of ethanolic extract of red spinach on the prevention against atherosclerosis based on the level of Low-Density Lipoprotein and the histopathological feature of aorta in male Sprague-Dawley rats.
Pulsed power molten salt battery
NASA Technical Reports Server (NTRS)
Argade, Shyam D.
1992-01-01
It was concluded that carbon cathodes with chlorine work well. Lithium alloy chlorine at 450 C, 1 atm given high power capability, high energy density, DC + pulsing yields 600 pulses, no initial peak, and can go to red heat without burn-up. Electrochemical performance at the cell and cell stack level out under demanding test regime. Engineering and full prototype development for advancing this technology is warranted.
Catania, Daniela; Richlen, Mindy L; Mak, Yim Ling; Morton, Steve L; Laban, Elizabeth H; Xu, Yixiao; Anderson, Donald M; Chan, Leo Lai; Berumen, Michael L
2017-09-01
This study confirms the presence of the toxigenic benthic dinoflagellates Gambierdiscus belizeanus and Ostreopsis spp. in the central Red Sea. To our knowledge, this is also the first report of these taxa in coastal waters of Saudi Arabia, indicating the potential occurrence of ciguatera fish poisoning (CFP) in that region. During field investigations carried out in 2012 and 2013, a total of 100 Turbinaria and Halimeda macroalgae samples were collected from coral reefs off the Saudi Arabian coast and examined for the presence of Gambierdiscus and Ostreopsis, two toxigenic dinoflagellate genera commonly observed in coral reef communities around the world. Both Gambierdiscus and Ostreopsis spp. were observed at low densities (<200 cells g -1 wet weight algae). Cell densities of Ostreopsis spp. were significantly higher than Gambierdiscus spp. at most of the sampling sites, and abundances of both genera were negatively correlated with seawater salinity. To assess the potential for ciguatoxicity in this region, several Gambierdiscus isolates were established in culture and examined for species identity and toxicity. All isolates were morphologically and molecularly identified as Gambierdiscus belizeanus. Toxicity analysis of two isolates using the mouse neuroblastoma cell-based assay for ciguatoxins (CTX) confirmed G. belizeanus as a CTX producer, with a maximum toxin content of 6.50±1.14×10 -5 pg P-CTX-1 eq. cell -1 . Compared to Gambierdiscus isolates from other locations, these were low toxicity strains. The low Gambierdiscus densities observed along with their comparatively low toxin contents may explain why CFP is unidentified and unreported in this region. Nevertheless, the presence of these potentially toxigenic dinoflagellate species at multiple sites in the central Red Sea warrants future study on their possible effects on marine food webs and human health in this region. Copyright © 2017 Elsevier B.V. All rights reserved.
Short-term responses of red squirrels to prescribed burning in the interior Pacific Northwest, USA
Robin E. Russell; John F. Lehmkuhl; Stephen T. Buckland; Victoria A. Saab
2010-01-01
We quantified changes in density of red squirrels (Tamiasciurus hudsonicus) in response to prescribed fire in mixed coniferous forests of Idaho and Washington, USA, using a Before-After-Control-Impact design. We found no evidence that low-severity prescribed fires affected density of red squirrels; we estimated the change in red squirrel densities...
The dynamics of health in wild field vole populations: a haematological perspective
Beldomenico, Pablo M.; Telfer, Sandra; Gebert, Stephanie; Lukomski, Lukasz; Bennett, Malcolm; Begon, Michael
2010-01-01
Summary Pathogens have been proposed as potentially important drivers of population dynamics, but while a few studies have investigated the impact of specific pathogens, the wealth of information provided by general indices of health has hardly been exploited. By evaluating haematological parameters in wild populations, our knowledge of the dynamics of health and infection may be better understood. Here, haematological dynamics in natural populations of field voles are investigated to determine environmental and host factors associated with indicators of inflammatory response (counts of monocytes and neutrophils) and of condition: measures of immunological investment (lymphocyte counts) and aerobic capacity (red blood cell counts). Individuals from three field vole populations were sampled monthly for 2 years. Comparisons with individuals kept under controlled conditions facilitated interpretation of field data. Mixed effects models were developed for each cell type to evaluate separately the effects of various factors on post-juvenile voles and mature breeding females. There were three well-characterized ‘physiological’ seasons. The immunological investment appeared lowest in winter (lowest lymphocyte counts), but red blood cells were at their highest levels and indices of inflammatory response at their lowest. Spring was characterized by a fall in red blood cell counts and peaks in indicators of inflammatory response. During the course of summer—autumn, red blood cell counts recovered, the immunological investment increased and the indicators of inflammatory response decreased. Poor body condition appeared to affect the inflammatory response (lower neutrophil and monocyte peaks) and the immunological investment (lower lymphocyte counts), providing evidence that the capacity to fight infection is dependent upon host condition. Breeding early in the year was most likely in females in better condition (high lymphocyte and red blood cell counts). All the haematological parameters were affected adversely by high population densities. PMID:18564292
Jauchem, James R; Bernhard, Joshua A; Cerna, Cesario Z; Lim, Tiffany Y; Seaman, Ronald L; Tarango, Melissa
2013-09-01
In previous studies hematocrit has been consistently increased in an anesthetized animal model after exposures to TASER(®) conducted energy weapons (CEWs). In the present study we analyzed changes in blood cell counts and red blood cell membrane proteins following two 30-s applications of a TASER C2 device (which is designed for civilian use). Hematocrit increased significantly from 33.2 ± 2.4 (mean ± SD) to 42.8 ± 4.6 % immediately after CEW exposure of eleven pigs (Sus scrofa). Red blood cell count increased significantly from 6.10 ± 0.55 × 10(12)/L to 7.45 ± 0.94 × 10(12)/L, and mean corpuscular volume increased significantly from 54.5 ± 2.4 fl to 57.8 ± 2.6 fl. Mean corpuscular hemoglobin concentration decreased significantly from 20.5 ± 0.7 to 18.5 ± 0.6 mM. Thirty protein spots (from two-dimensional sodium dodecyl sulfate polyacrylamide gel electrophoresis, selected for detailed comparison) exhibited greater densities 30-min post-exposure compared with pre-exposure values. A greater number of echinocytes were observed following CEW exposure. On the basis of these results it appears that, during the strong muscle contractions produced by TASER CEWs, a specific population of red blood cells (RBCs) may be released from the spleen or other reservoirs within the body. The total time of CEW exposure in the present study was relatively long compared with exposures in common law-enforcement scenarios. Despite statistically significant changes in red blood cell counts (and other measures directly related to RBCs), the alterations were short-lived. The transient nature of the changes would be likely to counteract any potentially detrimental effects.
Lisovskaya, Irina L; Shcherbachenko, Irina M; Volkova, Rimma I; Tikhonov, Vladimir P
2008-06-01
A study was made comparing the effects of two oxidants--phenazine methosulfate (50-1500 microM)+10 mM ascorbate and t-butyl hydroperoxide (1-3 mM)--on the volume-related parameters of normal human red blood cells. Incubation with either oxidative system for 20-30 min resulted in red blood cell density and osmotic resistance distribution shifts. Treatment with the phenazine methosulfate+ascorbate system in the presence of Ca(2+) led to cell shrinking, with the maximum effect being more than 20%. In contrast, under the same conditions, t-BHP caused cell swelling by up to 15%. Modification of the suspending medium (Ca(2+) removing, clotrimazole addition, or enrichment with K(+)) modulated the redistribution effects, suggesting that they were mediated to some extent by Gardos channel activation. These findings are important for understanding how oxidants modulate RBC cation channels.
Veerman, Joost; Saakes, Michel; Metz, Sybrand J; Harmsen, G Jan
2010-12-01
Electricity can be produced directly with reverse electrodialysis (RED) from the reversible mixing of two solutions of different salinity, for example, sea and river water. The literature published so far on RED was based on experiments with relatively small stacks with cell dimensions less than 10 × 10 cm(2). For the implementation of the RED technique, it is necessary to know the challenges associated with a larger system. In the present study we show the performance of a scaled-up RED stack, equipped with 50 cells, each measuring 25 × 75 cm(2). A single cell consists of an AEM (anion exchange membrane) and a CEM (cation exchange membrane) and therefore, the total active membrane area in the stack is 18.75 m(2). This is the largest dimension of a reverse electrodialysis stack published so far. By comparing the performance of this stack with a small stack (10 × 10 cm(2), 50 cells) it was found that the key performance parameter to maximal power density is the hydrodynamic design of the stack. The power densities of the different stacks depend on the residence time of the fluids in the stack. For the large stack this was negatively affected by the increased hydrodynamic losses due to the longer flow path. It was also found that the large stack generated more power when the sea and river water were flowing in co-current operation. Co-current flow has other advantages, the local pressure differences between sea and river water compartments are low, hence preventing leakage around the internal manifolds and through pinholes in the membranes. Low pressure differences also enable the use of very thin membranes (with low electrical resistance) as well as very open spacers (with low hydrodynamic losses) in the future. Moreover, we showed that the use of segmented electrodes increase the power output by 11%.
Bookchin, R M; Etzion, Z; Sorette, M; Mohandas, N; Skepper, J N; Lew, V L
2000-07-05
We describe a population of sickle cell anemia red cells (SS RBCs) ( approximately 4%) and a smaller fraction of normal RBCs (<0.03%) that fail to dehydrate when permeabilized to K(+) with either valinomycin or elevated internal Ca(2+). The nonshrinking, valinomycin-resistant (val-res) fractions, first detected by flow cytometry of density-fractionated SS RBCs, constituted up to 60% of the lightest, reticulocyte-rich (R1) cell fraction, and progressively smaller portions of the slightly denser R2 cells and discocytes. R1 val-res RBCs had a mean cell hemoglobin concentration of approximately 21 g of Hb per dl, and many had an elongated shape like "irreversibly sickled cells," suggesting a dense SS cell origin. Of three possible explanations for val-res cells, failure of valinomycin to K(+)-permeabilize the cells, low co-ion permeability, or reduced driving K(+) gradient, the latter proved responsible: Both SS and normal val-res RBCs were consistently high-Na(+) and low-K(+), even when processed entirely in Na-free media. Ca(2+) + A23187-induced K(+)-permeabilization of SS R1 fractions revealed a similar fraction of cal-res cells, whose (86)Rb uptake showed both high Na/K pump and leak fluxes. val-res/cal-res RBCs might represent either a distinct erythroid genealogy, or an "end-stage" of normal and SS RBCs. This paper focuses on the discovery, basic characterization, and exclusion of artifactual origin of this RBC fraction. Many future studies will be needed to clarify their mechanism of generation and full pathophysiological significance.
Red blood cells play a role in reverse cholesterol transport.
Hung, Kimberly T; Berisha, Stela Z; Ritchey, Brian M; Santore, Jennifer; Smith, Jonathan D
2012-06-01
Reverse cholesterol transport (RCT) involves the removal of cholesterol from peripheral tissue for excretion in the feces. Here, we determined whether red blood cells (RBCs) can contribute to RCT. We performed a series of studies in apolipoprotein AI-deficient mice where the high-density lipoprotein-mediated pathway of RCT is greatly diminished. RBCs carried a higher fraction of whole blood cholesterol than plasma in apolipoprotein AI-deficient mice, and as least as much of the labeled cholesterol derived from injected foam cells appeared in RBCs compared with plasma. To determine whether RBCs mediate RCT to the fecal compartment, we measured RCT in anemic and control apolipoprotein AI-deficient mice and found that anemia decreased RCT to the feces by over 35% after correcting for fecal mass. Transfusion of [(3)H]cholesterol-labeled RBCs led to robust delivery of the labeled cholesterol to the feces in apolipoprotein AI-deficient hosts. In wild-type mice, the majority of the blood cholesterol mass, as well as [(3)H]cholesterol derived from the injected foam cells, was found in plasma, and anemia did not significantly alter RCT to the feces after correction for fecal mass. The RBC cholesterol pool is dynamic and facilitates RCT of peripheral cholesterol to the feces, particularly in the low high-density lipoprotein state.
Sorting cells by their density
Norouzi, Nazila; Bhakta, Heran C.
2017-01-01
Sorting cells by their type is an important capability in biological research and medical diagnostics. However, most cell sorting techniques rely on labels or tags, which may have limited availability and specificity. Sorting different cell types by their different physical properties is an attractive alternative to labels because all cells intrinsically have these physical properties. But some physical properties, like cell size, vary significantly from cell to cell within a cell type; this makes it difficult to identify and sort cells based on their sizes alone. In this work we continuously sort different cells types by their density, a physical property with much lower cell-to-cell variation within a cell type (and therefore greater potential to discriminate different cell types) than other physical properties. We accomplish this using a 3D-printed microfluidic chip containing a horizontal flowing micron-scale density gradient. As cells flow through the chip, Earth’s gravity makes each cell move vertically to the point where the cell’s density matches the surrounding fluid’s density. When the horizontal channel then splits, cells with different densities are routed to different outlets. As a proof of concept, we use our density sorter chip to sort polymer microbeads by their material (polyethylene and polystyrene) and blood cells by their type (white blood cells and red blood cells). The chip enriches the fraction of white blood cells in a blood sample from 0.1% (in whole blood) to nearly 98% (in the output of the chip), a 1000x enrichment. Any researcher with access to a 3D printer can easily replicate our density sorter chip and use it in their own research using the design files provided as online Supporting Information. Additionally, researchers can simulate the performance of a density sorter chip in their own applications using the Python-based simulation software that accompanies this work. The simplicity, resolution, and throughput of this technique make it suitable for isolating even rare cell types in complex biological samples, in a wide variety of different research and clinical applications. PMID:28723908
Tang, Qing-Qing; Fang, Zhi-Guo; Ji, Wen-Wen; Xia, Hui-Long
2014-11-01
Effect of light quality, including red light, blue light, white light, red and blue mixing light with ratios of 8: 1, 8:2 and 8 : 3, on the growth characteristics and biochenmical composition of Chlorella pyrenoidosa was investigated based on light emitting diode (LED). Results showed that Chlorella pyrenoidosa grew best under blue light, and the optical density, specific growth rate and biomass of Chlorella pyrenoidosa was about 2.4, 0.10 d(-1) and 0.64 g x L(-1), respectively, while the optical density of Chlorella pyrenoidosa was between 1.0 and 1.7, the specific growth rate was between 0.07-0.10 d(-1) and the biomass was between 0.27 and 0.38 g x L(-1) under other light quality after 30 days of cultivation. Under blue light, the optical density, specific growth rate and biomass of Chlorella pyrenoidosa was approximately 2.05 times, 1.33 times and 2.06 times higher than red light, respectively. Moreover, red and blue mixing light was conducive to the synthesis of chlorophyll a and β-carotene of Chlorella pyrenoidosa, and blue light could promote the synthesis of chlorophyll b. Chlorophyll a and carotenoids content of Chlorella pyrenoidosa was 13.5 mg xg(-1) and 5.8 mg x g(-1) respectively under red and blue mixing light with a ratio of 8:1, while it was 8.4 mg x g(-1) and 3.6 mg x g(-1) respectively under blue light. Red and blue mixing light was more conducive to protein and total lipid content per dry cell of Chlorella pyrenoidosa. Protein and total lipid content was 489.3 mg x g(-1) and 311.2 mg x g(-1) under red and blue mixing light with a ratio of 8 : 3, while it was 400.9 mg x g(-1) and 231.9 mg x g(-1) respectively under blue light.
Hyono, Atsushi; Gaboriaud, Fabien; Mazda, Toshio; Takata, Youichi; Ohshima, Hiroyuki; Duval, Jérôme F L
2009-09-15
The stability of native and enzyme-treated human red blood cells of type A (Rh D positive) against agglutination is investigated under conditions where it is mediated by immunoglobuline G (IgG) anti-D antibody binding. The propensity of cells to agglutinate is related to their interphasic (electrokinetic) properties. These properties significantly depend on the concentration of proteolytic papain enzyme and protease-free neuraminidase enzyme that the cells are exposed to. The analysis is based on the interpretation of electrophoretic data of cells by means of the numerical theory for the electrokinetics of soft (bio)particles. A significant reduction of the hydrodynamic permeability of the external soft glycoprotein layer of the cells is reported under the action of papain. This reflects a significant decrease in soft surface layer thickness and a loss in cell surface integrity/rigidity, as confirmed by nanomechanical AFM analysis. Neuraminidase action leads to an important decrease in the interphase charge density by removing sialic acids from the cell soft surface layer. This is accompanied by hydrodynamic softness modulations less significant than those observed for papain-treated cells. On the basis of these electrohydrodynamic characteristics, the overall interaction potential profiles between two native cells and two enzyme-treated cells are derived as a function of the soft surface layer thickness in the Debye-Hückel limit that is valid for cell suspensions under physiological conditions (approximately 0.16 M). The thermodynamic computation of cell suspension stability against IgG-mediated agglutination then reveals that a decrease in the cell surface layer thickness is more favorable than a decrease in interphase charge density for inducing agglutination. This is experimentally confirmed by agglutination data collected for papain- and neuraminidase-treated cells.
Red blood cell generation by three-dimensional aggregate cultivation of late erythroblasts.
Lee, EunMi; Han, So Yeon; Choi, Hye Sook; Chun, Bokhwan; Hwang, Byunghee; Baek, Eun Jung
2015-02-01
Stem cell-derived erythroid cells hold great potential for the treatment of blood-loss anemia and for erythropoiesis research; however, cultures using conventional flat plates or bioreactors have failed to show promising results. By mimicking the in vivo bone marrow (BM) environment in which most erythroid cells are physically aggregated, we show that a three-dimensional (3D) aggregate culture system facilitates erythroid cell maturation and red blood cell (RBC) production more effectively than two-dimensional high-density cell cultivation. Late erythroblasts (polychromatic or orthochromatic erythroblasts) were differentiated from cord blood CD34(+) cells over 15 days and then allowed to form tight aggregates at a minimum density of 1×10(7) cells/mL for 2-3 days. To scale up the cell culture and to make the media supply efficient throughout the cell aggregates, several macroporous microcarriers and porous scaffolds were applied to the 3D culture system. In comparison to control culture conditions, erythroid cells in 3D aggregates were significantly more differentiated toward RBCs with significantly reduced nuclear dysplasia. When 3D culture was performed inside macroporous microcarriers, the cell culture scale was increased and cells exhibited enhanced differentiation and enucleation. Microcarriers with a pore diameter of approximately 400 μm produced more mature cells than those with a smaller pore diameter. In addition, this aggregate culture method minimized the culture space and media volume required. In conclusion, a 3D aggregate culture system can be used to generate transfusable human erythrocytes at the terminal maturation stage, mimicking the in vivo BM microenvironment. Porous structures can efficiently maximize the culture scale, enabling large-scale production of RBCs. These results enhance our understanding of the importance of physical contact among late erythroblasts for their final maturation into RBCs.
ACTIVITY OF DISSOCIATED AND REASSOCIATED 19S ANTI-γ-GLOBULINS
Schrohenloher, Ralph E.; Kunkel, Henry G.; Tomasi, Thomas B.
1964-01-01
19S anti-γ-globulins were isolated in a high state of purity from the sera of two patients with rheumatoid arthritis. Following reduction with ethyl mercaptan and alkylation by iodoacetamide, fragments were produced which retained the capacity to combine with 7S γ-globulin. The fragments from one of the 19S anti-γ-globulins agglutinated red cells coated with incomplete anti-Rh antibodies. This activity was shown by density gradient ultracentrifugation to be associated with low molecular weight fractions. The agglutination of the coated red cells by the fragments was strongly inhibited by normal and myeloma 7S γ-globulins and showed a greater specificity than the parent 19S material. Analytical ultracentrifuge experiments demonstrated that the fragments from either of the 19S anti-γ-globulins formed complexes with 7S γ-globulin. Reassociation of the dissociated fragments through reformation of disulfide bonds resulted in the formation of fast sedimenting molecules having properties similar to those of the untreated 19S material in respect to precipitation with aggregated γ-globulin and agglutination of coated red cells. PMID:14238936
NASA Astrophysics Data System (ADS)
Kobayashi, Takuma; Tagawa, Ayato; Noda, Toshihiko; Sasagawa, Kiyotaka; Tokuda, Takashi; Hatanaka, Yumiko; Tamura, Hideki; Ishikawa, Yasuyuki; Shiosaka, Sadao; Ohta, Jun
2010-11-01
The combination of optical imaging with voltage-sensitive dyes is a powerful tool for studying the spatiotemporal patterns of neural activity and understanding the neural networks of the brain. To visualize the potential status of multiple neurons simultaneously using a compact instrument with high density and a wide range, we present a novel measurement system using an implantable biomedical photonic LSI device with a red absorptive light filter for voltage-sensitive dye imaging (BpLSI-red). The BpLSI-red was developed for sensing fluorescence by the on-chip LSI, which was designed by using complementary metal-oxide-semiconductor (CMOS) technology. A micro-electro-mechanical system (MEMS) microfabrication technique was used to postprocess the CMOS sensor chip; light-emitting diodes (LEDs) were integrated for illumination and to enable long-term cell culture. Using the device, we succeeded in visualizing the membrane potential of 2000-3000 cells and the process of depolarization of pheochromocytoma cells (PC12 cells) and mouse cerebral cortical neurons in a primary culture with cellular resolution. Therefore, our measurement application enables the detection of multiple neural activities simultaneously.
Kaul, D K; Liu, X D
1999-01-01
Although the mean corpuscular hemoglobin concentration (MCHC) plays a dominant role in the rheologic behavior of deoxygenated density-defined sickle red blood cells (SS RBCs), previous studies have not explored the relationship between the rate of deoxygenation and the bulk viscosity of SS RBCs at a given MCHC. In the present study, we have subjected density-defined SS classes (i.e., medium-density SS4 and dense SS5 discocytes) to varying deoxygenation rates. This approach has allowed us to minimize the effects of SS RBC heterogeneity and investigate the effect of deoxygenation rates at a given MCHC. The results show that the percentages of granular cells, classic sickle cells and holly leaf forms in deoxygenated samples are significantly influenced by the rate of deoxygenation and the MCHC of a given discocyte subpopulation. Increasing the deoxygenation rate using high K+ medium (pH 6.8), results in a greater percentage of granular cells in SS4 suspensions, accompanied by a pronounced increase in the bulk viscosity of these cells compared with gradually deoxygenated samples (mainly classic sickle cells and holly leaf forms). The effect of MCHC becomes apparent when SS5 dense cells are subjected to varying deoxygenation rates. At a given deoxygenation rate, SS5 dense discocytes show a greater increase in the percentage of granular cells than that observed for SS4 RBCs. Also, at a given deoxygenation rate, SS5 suspensions exhibit a higher viscosity than SS4 suspensions with fast deoxygenation resulting in maximal increase in viscosity. Although MCHC is the main determinant of SS RBC rheologic behavior, these studies demonstrate for the first time that at a given MCHC, the rate of deoxygenation (hence HbS polymerization rates) further modulates the rheologic behavior of SS RBCs. Thus, both MCHC and the deoxygenation rate may contribute to microcirculatory flow behavior of SS RBCs.
Housler, Greggory J; Miki, Toshio; Schmelzer, Eva; Pekor, Christopher; Zhang, Xiaokui; Kang, Lin; Voskinarian-Berse, Vanessa; Abbot, Stewart; Zeilinger, Katrin; Gerlach, Jörg C
2012-02-01
Continuous production of red blood cells (RBCs) in an automated closed culture system using hematopoietic stem cell (HSC) progenitor cell populations is of interest for clinical application because of the high demand for blood transfusions. Previously, we introduced a four-compartment bioreactor that consisted of two bundles of hollow fiber microfiltration membranes for transport of culture medium (forming two medium compartments), interwoven with one bundle of hollow fiber membranes for transport of oxygen (O(2)), carbon dioxide (CO(2)), and other gases (forming one gas compartment). Small-scale prototypes were developed of the three-dimensional (3D) perfusion cell culture systems, which enable convection-based mass transfer and integral oxygenation in the cell compartment. CD34(+) HSC were isolated from human cord blood units using a magnetic separation procedure. Cells were inoculated into 2- or 8-mL scaled-down versions of the previously designed 800-mL cell compartment devices and perfused with erythrocyte proliferation and differentiation medium. First, using the small-scale 2-mL analytical scale bioreactor, with an initial seeding density of 800,000 cells/mL, we demonstrated approximately 100-fold cell expansion and differentiation after 7 days of culture. An 8-mL laboratory-scale bioreactor was then used to show pseudocontinuous production by intermediately harvesting cells. Subsequently, we were able to use a model to demonstrate semicontinuous production with up to 14,288-fold expansion using seeding densities of 800,000 cells/mL. The down-scaled culture technology allows for expansion of CD34(+) cells and stimulating these progenitors towards RBC lineage, expressing approximately 40% CD235(+) and enucleation. The 3D perfusion technology provides an innovative tool for studies on RBC production, which is scalable.
Chang, Yu-Jen; Tien, Kuei-Erh; Wen, Cheng-Hao; Hsieh, Tzu-Bou; Hwang, Shiaw-Min
2014-04-01
Very small embryonic-like (VSEL) stem cells are a rare cell population present in bone marrow, cord blood and other tissues that displays a distinct small cell size and the ability to give rise to cells of the three germ layers. VSEL stem cells were reported to be discarded in the red blood cell fraction by Ficoll-Paque density gradient centrifugation during the processing of bone marrow and cord blood specimens. However, most cord blood banks do not include density gradient centrifugation in their procedures while red blood cells are removed by Hespan sedimentation following the Cord Blood Transplantation Study cord blood bank standard operating procedures (COBLT SOP). To clarify the retention of VSEL stem cells, we investigated the recovery of VSEL stem cells following COBLT SOP guidelines. The recovery of CD45(-)/Lin(-)/SSEA-4(+) VSEL stem cells of umbilical cord blood was examined by flow cytometry before and after COBLT SOP processing, and relative expression of pluripotent genes was analyzed by quantitative polymerase chain reaction. CD45(-)/Lin(-)/SSEA-4(+) VSEL stem cells were mostly recovered in the final products following COBLT SOP guidelines. The expression of pluripotent genes could be maintained at >80% in products after hetastarch (Hespan; B. Braun Medical Inc., Irvine, CA, USA) processing. The rare sub-population of CD45(-)/Lin(-)/SSEA-4(+) VSEL stem cells survived after Hespan sedimentation. This finding suggests that umbilical cord blood units cryopreserved by COBLT SOP in cord blood banks should retain most VSEL stem cells present in the un-processed specimens. Copyright © 2014 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.
Housler, Greggory J.; Miki, Toshio; Schmelzer, Eva; Pekor, Christopher; Zhang, Xiaokui; Kang, Lin; Voskinarian-Berse, Vanessa; Abbot, Stewart; Zeilinger, Katrin
2012-01-01
Continuous production of red blood cells (RBCs) in an automated closed culture system using hematopoietic stem cell (HSC) progenitor cell populations is of interest for clinical application because of the high demand for blood transfusions. Previously, we introduced a four-compartment bioreactor that consisted of two bundles of hollow fiber microfiltration membranes for transport of culture medium (forming two medium compartments), interwoven with one bundle of hollow fiber membranes for transport of oxygen (O2), carbon dioxide (CO2), and other gases (forming one gas compartment). Small-scale prototypes were developed of the three-dimensional (3D) perfusion cell culture systems, which enable convection-based mass transfer and integral oxygenation in the cell compartment. CD34+ HSC were isolated from human cord blood units using a magnetic separation procedure. Cells were inoculated into 2- or 8-mL scaled-down versions of the previously designed 800-mL cell compartment devices and perfused with erythrocyte proliferation and differentiation medium. First, using the small-scale 2-mL analytical scale bioreactor, with an initial seeding density of 800,000 cells/mL, we demonstrated approximately 100-fold cell expansion and differentiation after 7 days of culture. An 8-mL laboratory-scale bioreactor was then used to show pseudocontinuous production by intermediately harvesting cells. Subsequently, we were able to use a model to demonstrate semicontinuous production with up to 14,288-fold expansion using seeding densities of 800,000 cells/mL. The down-scaled culture technology allows for expansion of CD34+ cells and stimulating these progenitors towards RBC lineage, expressing approximately 40% CD235+ and enucleation. The 3D perfusion technology provides an innovative tool for studies on RBC production, which is scalable. PMID:21933020
Long-term dynamics of freshwater red tide in shallow lake in central Japan.
Hirabayashi, Kimio; Yoshizawa, Kazuya; Yoshida, Norihiko; Ariizumi, Kazunori; Kazama, Futaba
2007-01-01
The aim of this study is to clarify the long-term dynamics of the red tide occurring in Lake Kawaguchi. The measurement of environmental factors and water sampling were carried out monthly at a fixed station in Lake Kawaguchi's center basin from April 1993 to March 2004. On June 26, 1995, the horizontal distribution ofPeridinium bipes was investigated using a plastic pipe, obtaining 0∼1-m layers of water column samples at 68 locations across the entire lake. P. bipes showed an explosive growth and formed a freshwater red tide in the early summer of 1995, when the nutrient level was higher than those in the other years, particularly the phosphate concentration in the surface layer. The dissolved total phosphorus (DTP) concentration was sufficient forP. bipes growth in that year. In the study of its horizontal distribution,P. bipes was found at all the locations. The numbers of cells per milliliter ranged from 67 to 5360, averaging 1094±987 cells/ml, with particularly high densities along the northern shore. Since then,P. bipes has annually averaged about 25 cells/ml in Lake Kawaguchi. We observed that the red tide caused byP. bipes correlates with a high DTP concentration in Lake Kawaguchi.
Current density reversibly alters metabolic spatial structure of exoelectrogenic anode biofilms
NASA Astrophysics Data System (ADS)
Sun, Dan; Cheng, Shaoan; Zhang, Fang; Logan, Bruce E.
2017-07-01
Understanding how current densities affect electrogenic biofilm activity is important for wastewater treatment as current densities can substantially decrease at COD concentrations greater than those suitable for discharge to the environment. We examined the biofilm's response, in terms of viability and enzymatic activity, to different current densities using microbial electrolysis cells with a lower (0.7 V) or higher (0.9 V) added voltage to alter current production. Viability was assessed using florescent dyes, with dead cells identified on the basis of dye penetration due to a compromised cell outer-membrane (red), and live cells (intact membrane) fluorescing green. Biofilms operated with 0.7 V produced 2.4 ± 0.2 A m-2, and had an inactive layer near the electrode and a viable layer at the biofilm-solution interface. The lack of cell activity near the electrode surface was confirmed by using an additional dye that fluoresces only with enzymatic activity. Adding 0.9 V increased the current by 61%, and resulted in a single, more homogeneous and active biofilm layer. Switching biofilms between these two voltages produced outcomes associated with the new current rather than the previous biofilm conditions. These findings suggest that maintaining higher current densities will be needed to ensure long-term viability electrogenic biofilms.
NASA Astrophysics Data System (ADS)
Zhang, Jian; Li, Tingyu
2017-09-01
Solar cells sensitized by polypyridyl Ru(II) complexes exhibit relatively high efficiency, however those photo-sensitizers did not absorb the photons in the far-red and near-infrared region. At present, squaraine dyes have received considerable attention as their attractively intrinsic red light absorption and unusual high molar extinction coefficient. Here we applied density functional theory and time dependent density functional theory to investigate the properties of electronically excited states of four squaraine dyes and their complexes with fullerene C70. The influences of different functionals, basis sets and solvent effects are evaluated. To understand the photophysical properties, the investigations are basing on a classification method which splits the squaraine dyes and their complexes with fullerene C70 into two units to characterize the intramolecular density distribution. We present the signatures of their electronically excited states which are characterized as local excitation or charge-transfer excitation. The relationship between open-circuit voltage and the number of intramolecular hydrogen bonds in squaraine dyes are discussed.
The Gardos channel is responsible for CDNB-induced dense sickle cell formation.
Shartava, A; McIntyre, J; Shah, A K; Goodman, S R
2000-07-01
The red blood cells (RBCs) derived from blood taken from homozygous sickle cell (SS) patients demonstrate densities that are inversely proportional to the intracellular reduced glutathione (GSH) content. Addition of 1 mM 1-chloro-2,4-dinitrobenzene (CDNB) to low-density sickle cells (LDSS), at 4 degrees C, results in a shift of LDSS erythrocytes to high-density sickle cells (HDSS), with corresponding decreases in GSH. We have previously demonstrated that this CDNB effect was due to increased K(+) leakage and that dense cell formation could be inhibited by clotrimazole (specific for the Gardos channel) but not DIOA (specific for the K(+)-Cl(-) co-transport system) at pH 7.4 (Shartava et al. Am. J. Hematol. 1999;62:19-24). Here we demonstrate that clotrimazole (10 microM) inhibits dense cell formation at pH 7.1 and 6.8, while DIOA (1 mM) has no effect. As pH 6.8 is the optimal pH for the K(+)-Cl(-) co-transport system, we can now reasonably conclude that damage to the Gardos channel is responsible for CDNB-induced dense cell formation. Copyright 2000 Wiley-Liss, Inc.
Tahlawi, Asma; Li, Kang
2018-01-01
Tissue vasculature efficiently distributes nutrients, removes metabolites, and possesses selective cellular permeability for tissue growth and function. Engineered tissue models have been limited by small volumes, low cell densities, and invasive cell extraction due to ineffective nutrient diffusion and cell-biomaterial attachment. Herein, we describe the fabrication and testing of ceramic hollow fibre membranes (HFs) able to separate red blood cells (RBCs) and mononuclear cells (MNCs) and be incorporated into 3D tissue models to improve nutrient and metabolite exchange. These HFs filtered RBCs from human umbilical cord blood (CB) suspensions of 20% RBCs to produce 90% RBC filtrate suspensions. When incorporated within 5 mL of 3D collagen-coated polyurethane porous scaffold, medium-perfused HFs maintained nontoxic glucose, lactate, pH levels, and higher cell densities over 21 days of culture in comparison to nonperfused 0.125 mL scaffolds. This hollow fibre bioreactor (HFBR) required a smaller per-cell medium requirement and operated at cell densities > 10-fold higher than current 2D methods whilst allowing for continuous cell harvest through HFs. Herein, we propose HFs to improve 3D cell culture nutrient and metabolite diffusion, increase culture volume and cell density, and continuously harvest products for translational cell therapy biomanufacturing protocols. PMID:29760729
Dinkla, Sip; Peppelman, Malou; Van Der Raadt, Jori; Atsma, Femke; Novotný, Vera M J; Van Kraaij, Marian G J; Joosten, Irma; Bosman, Giel J C G M
2014-04-01
Exposure of phosphatidylserine on the outside of red blood cells contributes to recognition and removal of old and damaged cells. The fraction of phosphatidylserine-exposing red blood cells varies between donors, and increases in red blood cell concentrates during storage. The susceptibility of red blood cells to stress-induced phosphatidylserine exposure increases with storage. Phosphatidylserine exposure may, therefore, constitute a link between donor variation and the quality of red blood cell concentrates. In order to examine the relationship between storage parameters and donor characteristics, the percentage of phosphatidylserine-exposing red blood cells was measured in red blood cell concentrates during storage and in fresh red blood cells from blood bank donors. The percentage of phosphatidylserine-exposing red blood cells was compared with red blood cell susceptibility to osmotic stress-induced phosphatidylserine exposure in vitro, with the regular red blood cell concentrate quality parameters, and with the donor characteristics age, body mass index, haemoglobin level, gender and blood group. Phosphatidylserine exposure varies between donors, both on red blood cells freshly isolated from the blood, and on red blood cells in red blood cell concentrates. Phosphatidylserine exposure increases with storage time, and is correlated with stress-induced phosphatidylserine exposure. Increased phosphatidylserine exposure during storage was found to be associated with haemolysis and vesicle concentration in red blood cell concentrates. The percentage of phosphatidylserine-exposing red blood cells showed a positive correlation with the plasma haemoglobin concentration of the donor. The fraction of phosphatidylserine-exposing red blood cells is a parameter of red blood cell integrity in red blood cell concentrates and may be an indicator of red blood cell survival after transfusion. Measurement of phosphatidylserine exposure may be useful in the selection of donors and red blood cell concentrates for specific groups of patients.
Derfus, Gayle E; Dizon-Maspat, Jemelle; Broddrick, Jared T; Velayo, Arleene C; Toschi, Josh D; Santuray, Rodell T; Hsu, Stephen K; Winter, Charles M; Krishnan, Rajesh; Amanullah, Ashraf
2014-01-01
While many antibody therapeutics are formulated at low concentration (~10–20 mg/mL) for intravenous administration, high concentration (> 100 mg/mL) formulations may be required for subcutaneous delivery in certain clinical indications. For such high concentration formulations, product color is more apparent due to the higher molecular density across a given path-length. Color is therefore a product quality attribute that must be well-understood and controlled, to demonstrate process consistency and enable clinical trial blinding. Upon concentration of an IgG4 product at the 2000 L manufacturing scale, variability in product color, ranging from yellow to red, was observed. A small-scale experimental model was developed to assess the effect of processing conditions (medium composition and harvest conditions) on final bulk drug substance (BDS) color. The model was used to demonstrate that, for two distinct IgG4 products, red coloration occurred only in the presence of disulfide reduction-mediated antibody dissociation. The red color-causing component was identified as vitamin B12, in the hydroxocobalamin form, and the extent of red color was correlated with the cobalt (vitamin B12) concentration in the final pools. The intensity of redness in the final BDS was modulated by changing the concentration of vitamin B12 in the cell culture media. PMID:24552690
Utilizing the algicidal activity of aminoclay as a practical treatment for toxic red tides
Lee, Young-Chul; Jin, EonSeon; Jung, Seung Won; Kim, Yeon-Mi; Chang, Kwang Suk; Yang, Ji-Won; Kim, Si-Wouk; Kim, Young-Ok; Shin, Hyun-Jae
2013-01-01
In recent decades, harmful algal blooms (HABs) – commonly known as red tides – have increasingly impacted human health, caused significant economic losses to fisheries and damaged coastal environments and ecosystems. Here, we demonstrate a method to control and suppress HABs through selective algal lysis. The approach harnesses the algicidal effects of aminoclays, which are comprised of a high density of primary amine groups covalently bonded by metal cation backbones. Positively charged colloidals of aminoclays induce cell lysis in HABs within several minutes exposure but have negligible impact on non-harmful phytoplankton, zooplankton and farmed fish. This selective lysis is due to the ammonium characteristics of the aminoclay and the electrostatic attraction between the clay nanoparticles and the algal cells. In contrast, yellow loess clay, a recognized treatment for HABs, causes algal flocs with little cell lysis. Thus, the aminoclay loading can be effective for the mitigation of HABs. PMID:23416422
Utilizing the algicidal activity of aminoclay as a practical treatment for toxic red tides.
Lee, Young-Chul; Jin, EonSeon; Jung, Seung Won; Kim, Yeon-Mi; Chang, Kwang Suk; Yang, Ji-Won; Kim, Si-Wouk; Kim, Young-Ok; Shin, Hyun-Jae
2013-01-01
In recent decades, harmful algal blooms (HABs) - commonly known as red tides - have increasingly impacted human health, caused significant economic losses to fisheries and damaged coastal environments and ecosystems. Here, we demonstrate a method to control and suppress HABs through selective algal lysis. The approach harnesses the algicidal effects of aminoclays, which are comprised of a high density of primary amine groups covalently bonded by metal cation backbones. Positively charged colloidals of aminoclays induce cell lysis in HABs within several minutes exposure but have negligible impact on non-harmful phytoplankton, zooplankton and farmed fish. This selective lysis is due to the ammonium characteristics of the aminoclay and the electrostatic attraction between the clay nanoparticles and the algal cells. In contrast, yellow loess clay, a recognized treatment for HABs, causes algal flocs with little cell lysis. Thus, the aminoclay loading can be effective for the mitigation of HABs.
Chuenniyom, Wansiri; Meksumpun, Charumas; Meksumpun, Shettapong
2012-01-01
This study aimed to analyze the impacts of nutrients and related aquatic factors on changes in the Noctiluca population of the Tha Chin estuary, a nutrient-rich estuary located in the inner Gulf of Thailand. Field surveys were carried out at 30 stations during November 2009 to August 2010. The results indicated high levels of dissolved inorganic nitrogen (DIN; 13.89-46.99 μmol/L) and PO(4)(3-)-P (0.20-3.05 μmol/L) where the Noctiluca red tide occurred, particularly during the high-loading period. Dense populations were usually found in the outer part of the estuary with comparatively high salinity (25-29 psu). The highest Noctiluca density was 72,333 cells L(-1) and the cell diameters ranged between 360 and 460 μm. Proportions of small-sized cells (P(s); less than 300 μm) varied over time. In this study, P(s) showed a positive correlation with levels of PO(4)(3-)-P, while the total population density was significantly affected by levels of NH(4)(+)-N and DIN (p < 0.05). Overall, PO(4)(3-)-P influenced the development of the Noctiluca red tide, with the limitation of PO(4)(3-)-P levels to below 1 μmol/L suggested for controlling Noctiluca red tide outbreaks at their origin. To support environmental conservation and maintain sustainable production in the estuary, the levels of PO(4)(3-)-P should be considered for the further effective development of water quality standards in estuarine zones.
NASA Technical Reports Server (NTRS)
Todd, P. W.
1985-01-01
The objectives of the red blood cell experiments were to provide a visual check on the electrophoretic process and especially electroosmotic flow in space as well as to provide test separations of non-degradable standard particles for comparison with the separations of the three viable cell types studied on the Apollo-Soyuz Test Project. Determination of the maximum concentrations of cells that can be separated in column electrophore was a significant goal. Two of the eight columns were available for red cell experiments, so two concentrations of human and rabbit RBC mixtures were used. The objectives of another experiment were to evaluate the reproducibility of microgravity electrophoretic separation of living kidney cells, to separate cells with highly viability despite two freeze-thaw cycles, and to optimize the physical conditions of cell separation. Owing to the uncertain heterogeneity of the starting material, the experimental design does not assess resolution in microgravity, but improved separability was sought in comparison to density-gradient electrophoresis or continuous-flow electrophoresis. Efforts were made to increase cell yield and cell viability and to assess reproducibility directly.
In Vitro UV-Visible Spectroscopy Study of Yellow Laser Irradiation on Human Blood
NASA Astrophysics Data System (ADS)
Fuad, Siti Sakinah Mohd; Suardi, N.; Mustafa, I. S.
2018-04-01
This experimental study was performed to investigate the effect of low level yellow laser of 589nm wavelength with various laser irradiation time. Human blood samples with random diseases are irradiated with yellow laser of power density of 450mW/cm2 from 10 minutes to 60 minutes at 10 minutes intervals. The morphology of the red blood cell were also observed for different irradiation time. The result shows that there is a significant different in the absorption of light with varying laser irradiation time (p<0.01). The maximum absorption recorded at 40 minutes of irradiation at 340nm peak. Blood smear of the samples reveals that there are observable changes in the morphology of the red blood cell at 40 minutes and 60 minutes of irradiation.
Cevallos-Cevallos, Juan M; Gu, Ganyu; Danyluk, Michelle D; van Bruggen, Ariena H C
2012-11-01
Salmonella enterica strains with rdar (red dry and rough) and saw (smooth and white) morphotypes have previously been associated with tomato outbreaks but the dispersal mechanisms of these morphotypes are still poorly understood. In this study, Salmonella adhesion was distinguished from attachment by comparing different contact periods. Initial adhesion of rdar and saw morphotypes of Salmonella was compared in relation to tomato plants with different leaf trichome densities. Trichome densities were increased or reduced by treatment with jasmonic or salicylic acid, respectively. The overall effect of Salmonella morphotype and trichome density on splash dispersal was assessed in a rain simulator and correlated to cell hydrophobicity and initial adhesion. The presence of the rdar morphotype increased initial adhesion at high trichome densities but not at low trichome densities. Attachment of the rdar strain occurred after 30s contact time regardless of trichome density. Splash dispersal was slightly further for the saw morphotype than the rdar morphotype of S. enterica at all trichome densities. Salmonella cells of both morphotypes survived significantly better on the surface of high trichome density leaflets. Copyright © 2012 Elsevier B.V. All rights reserved.
Yamauchi, Nobuhiro; Taguchi, Yoichiro; Kato, Hirohito; Umeda, Makoto
2018-03-01
Light-emitting diode (LED) is attracting attention as a new light source for phototherapy. However, its effects on periodontal tissue regeneration remain unknown. The aim of this study was to examine the effects of high-power, red LED irradiation on human periodontal ligament stem cells (PDLSCs), which play an important role in periodontal tissue regeneration. PDLSCs were derived from adult human third molars. The light source was red LED (peak wavelength: 650 nm). Energy densities ranging from 0 to 10 J/cm 2 were tested to determine the optimal dose. PDLSC proliferation was measured using two parameters: live cell protease and ATP levels. After the cells were induced to differentiate, the effect of LED irradiation on osteogenic differentiation and mineralization was examined, with particular focus on the extracellular signal-regulated kinase (ERK)1/2 signaling pathway using an ERK inhibitor (PD98059). LED irradiation at 8 J/cm 2 led to a significant increase in PDLSC proliferation and enhanced Runx2 and Osterix mRNA expression, Alkaline phosphatase activity, procollagen type I C-peptide and osteocalcin production, calcium deposition, and alizarin red S staining. In addition, LED induced the activation of ERK1/2, and the effects of LED on PDLSC proliferation, differentiation, and mineralization could be suppressed by treatment with PD98059. The results of this study show that 650-nm high-power, red, LED irradiation increases PDLSCs proliferation, and osteogenic differentiation and mineralization, mediated by ERK1/2 activation. These findings suggest that LED may be a useful tool for periodontal tissue regeneration. © 2018 American Academy of Periodontology.
Sorg, Nadine; Poppe, Carolin; Bunos, Milica; Wingenfeld, Eva; Hümmer, Christiane; Krämer, Ariane; Stock, Belinda; Seifried, Erhard; Bonig, Halvard
2015-06-01
Red blood cell (RBC) depletion is a standard technique for preparation of ABO-incompatible bone marrow transplants (BMTs). Density centrifugation or apheresis are used successfully at clinical scale. The advent of a bone marrow (BM) processing module for the Spectra Optia (Terumo BCT) provided the initiative to formally compare our standard technology, the COBE2991 (Ficoll, manual, "C") with the Spectra Optia BMP (apheresis, semiautomatic, "O"), the Sepax II NeatCell (Ficoll, automatic, "S"), the Miltenyi CliniMACS Prodigy density gradient separation system (Ficoll, automatic, "P"), and manual Ficoll ("M"). C and O handle larger product volumes than S, P, and M. Technologies were assessed for RBC depletion, target cell (mononuclear cells [MNCs] for buffy coats [BCs], CD34+ cells for BM) recovery, and cost/labor. BC pools were simultaneously purged with C, O, S, and P; five to 18 BM samples were sequentially processed with C, O, S, and M. Mean RBC removal with C was 97% (BCs) or 92% (BM). From both products, O removed 97%, and P, S, and M removed 99% of RBCs. MNC recovery from BC (98% C, 97% O, 65% P, 74% S) or CD34+ cell recovery from BM (92% C, 90% O, 67% S, 70% M) were best with C and O. Polymorphonuclear cells (PMNs) were depleted from BCs by P, S, and C, while O recovered 50% of PMNs. Time savings compared to C or M for all tested technologies are considerable. All methods are in principle suitable and can be selected based on sample volume, available technology, and desired product specifications beyond RBC depletion and MNC and/or CD34+ cell recovery. © 2015 AABB.
Continuous blood densitometry - Fluid shifts after graded hemorrhage in animals
NASA Technical Reports Server (NTRS)
Hinghofer-Szalkay, H.
1986-01-01
Rapid fluid shifts in four pigs and two dogs subjected to graded hemorrhage are investigated. Arterial blood density (BD), mean arterial pressure (MAP), central venous pressure (CVP), arterial plasma density (PD), hematocrit (Hct) and erythrocyte density were measured. The apparatus and mechancial oscillator technique for measuring density are described. Fluid shifts between red blood cells and blood plasma and alterations in the whole-body-to-large vessel Hct, F(cell) are studied using two models. The bases of the model calculations are discussed. A decrease in MAP, CVP, and BP is detected at the beginning of hemorrhaging; continued bleeding results in further BD decrease correlating with volume displacement. The data reveal that at 15 ml/kg blood loss the mean PD and BD dropped by 0.99 + or - 0.15 and 2.42 + or 0.26 g/liter, respectively, and the Hct dropped by 2.40 + or 0.47 units. The data reveal that inward-shifted fluid has a higher density than normal ultrafiltrate and/or there is a rise in the F(cell) ratio. It is noted that rapid fluid replacement ranged from 5.8 + or - 0.8 to 10.6 + or - 2.0 percent of the initial plasma volume.
Wong, C Kwan; Wong, C Kim
2003-09-01
A red tide was detected in the inner parts of Tolo Harbour, Hong Kong, in November 2000. Water samples were collected from a fixed station at the centre of the red tide patch for microscopic analysis of phytoplankton community composition and high performance liquid chromatography (HPLC) analysis of phytoplankton pigments. At the peak of the red tide on 24 November 2000, phytoplankton was dominated by the dinoflagellate Scrippsiella trochoidea. The red tide began to decline at the end of November and, by 1 December 2000, the phytoplankton was dominated by diatoms. Chlorophylls and carotenoids in water samples were analysed using HPLC pigment separation technique. Dinoflagellates were indicated by the signature pigment peridinin. Significant correlation (r=0.999) was found between the peridinin concentration and dinoflagellate density. A decrease in peridinin and an increase in fucoxanthin, a major carotenoid in diatoms, marked the shift in phytoplankton composition at the end of the red tide. HPLC analysis also revealed the occurrence of minor phytoplankton groups that are difficult to identify by light microscopy. Red tide monitoring and study of red tide dynamics in Hong Kong have been based on cell counting and spectrophotometric or fluorometric measurement of chlorophyll a. HPLC pigment analysis provides an effective alternative for investigating phytoplankton dynamics during red tide and other algal blooms.
Kim, Young Sug; Jeong, Chang Su; Seong, Gi Tak; Han, In Sung; Lee, Young Sik
2010-09-01
The diurnal vertical migration of Cochlodinium polykrikoides (C. polykrikoides), which caused a red tide in the Korean coastal waters of the East Sea/Sea of Japan in September 2003, was examined by determining the time-dependent changes in the density of living cells in relation to the depth of the water column. The ascent of this species into the surface layer (depth of water 2 m) occurred during 1400-1500. The descent started at 1600 and a high distribution rate (86%) at 15-20 m was observed at 0300. During the ascent, the cells were widely distributed at each depth level from 0600 hr and at 0800-1100, the cells were primarily distributed in the middle layer (0-6 m). The concentration of dissolved inorganic nitrogen was generally < or = 2.86 micromol l(-1), but at 1400-1500, the concentration in the surface layer reduced to < or = 0.14 micromol l(-1). Moreover, the concentration gradually increased as the depth increased to > or = 5 m. These results showed that the nutrient-consumption rate associated with the proliferation of C. polykrikoides during a red tide is more influenced by the inorganic-nitrogen resources ratherthan the inorganic-phosphorus compounds.
Chen, Junxian; Liu, Qingyu; Li, Hao; Zhao, Zhigang; Lu, Zhiyun; Huang, Yan; Xu, Dingguo
2018-01-01
Squaraine core based small molecules in bulk heterojunction organic solar cells have received extensive attentions due to their distinguished photochemical properties in far red and infrared domain. In this paper, combining theoretical simulations and experimental syntheses and characterizations, three major factors (fill factor, short circuit and open-cirvuit voltage) have been carried out together to achieve improvement of power conversion efficiencies of solar cells. As model material systems with D-A-D' framework, two asymmetric squaraines (CNSQ and CCSQ-Tol) as donor materials in bulk heterojunction organic solar cell were synthesized and characterized. Intensive density functional theory computations were applied to identify some direct connections between three factors and corresponding molecular structural properties. It then helps us to predict one new molecule of CCSQ'-Ox that matches all the requirements to improve the power conversion efficiency.
Aoki, Kazuhiro; Kameda, Takahiko; Yamatogi, Toshifumi; Ishida, Naoya; Hirae, Sou; Kawaguchi, Mayumi; Syutou, Toshio
2017-11-15
A massive bloom of the dinoflagellate Karenia mikimotoi appeared in 2014 in Imari Bay, Japan. Bloom dynamics and hydrographical conditions were examined by field survey. The bloom initially developed in the eastern area of Imari Bay, subsequently after rainfall during the neap tides, cell density exceeded over 10,000cellsml. Vertical distribution of K. mikimotoi was primarily controlled by the light intensity and secondarily by the water quality during the daytime. Almost all cell-density maxima occurred in depths with weak daytime light intensities of <300μmolm -2 s -1 . In some cases of weak light intensity, cell-density maxima occurred in depths with favorable hydrodynamic conditions for the growth. Spatially classified areas were identified by cluster analysis using the growth rate calculated from seawater temperature and salinity. This study quantitatively evaluated the environmental factors of the eastern area, where the bloom initially occurred, during the development of the bloom. Copyright © 2017 Elsevier Ltd. All rights reserved.
OpenRBC: Redefining the Frontier of Red Blood Cell Simulations at Protein Resolution
NASA Astrophysics Data System (ADS)
Tang, Yu-Hang; Lu, Lu; Li, He; Grinberg, Leopold; Sachdeva, Vipin; Evangelinos, Constantinos; Karniadakis, George
We present a from-scratch development of OpenRBC, a coarse-grained molecular dynamics code, which is capable of performing an unprecedented in silico experiment - simulating an entire mammal red blood cell lipid bilayer and cytoskeleton modeled by 4 million mesoscopic particles - on a single shared memory node. To achieve this, we invented an adaptive spatial searching algorithm to accelerate the computation of short-range pairwise interactions in an extremely sparse 3D space. The algorithm is based on a Voronoi partitioning of the point cloud of coarse-grained particles, and is continuously updated over the course of the simulation. The algorithm enables the construction of a lattice-free cell list, i.e. the key spatial searching data structure in our code, in O (N) time and space space with cells whose position and shape adapts automatically to the local density and curvature. The code implements NUMA/NUCA-aware OpenMP parallelization and achieves perfect scaling with up to hundreds of hardware threads. The code outperforms a legacy solver by more than 8 times in time-to-solution and more than 20 times in problem size, thus providing a new venue for probing the cytomechanics of red blood cells. This work was supported by the Department of Energy (DOE) Collaboratory on Mathematics for Mesoscopic Model- ing of Materials (CM4). YHT acknowledges partial financial support from an IBM Ph.D. Scholarship Award.
2012-10-01
digestion , prior to analysis of HIF-1 protein by western blot apaparatus. Representative blots are shown. Figure 3. The effects of cell density...mouse xenograft tumors treated for 56 weeks with letrozole, and maintained in phenol red-free (PRF) modified IMEM (Invitrogen) supplemented with 5...conditions for 2–3 days prior to cytospinning. Pelleted cells were fixed with 4 % para- formaldehyde and incubated with OCT4 antibody (Santa Cruz
Grams, Astrid E; Rehwald, Rafael; Schmittnägel, Charlotte; Schmidt, Thorsten; Tanislav, Christian; Berghoff, Martin; Krombach, Gabriele A; Moritz, Regina; Obert, Martin; Gizewski, Elke R; Glodny, Bernhard
The aim was to identify the factors influencing intracranial vessel density (VD). The Hounsfield units of the dense vessel and the contralateral side were measured in 34 patients with arterial clots, 20 with venous clots, and 196 without clots and correlated with skull thickness, density and dimensions, gender, age, red blood cell count (RBC), hemoglobin (HB), hematocrit (HT), creatinine, and sodium. Positive correlations were found between VD and HT, RBC, HB, creatinine, and occipital bone density. Density differences between the right and left intracranial vessels were more accurate (sensitivity/specificity/accuracy=0.91/0.93/0.93 and 0.75/0.87/0.85, respectively) for detecting clots than VD alone. HT, RBC, and HB are the main factors that correlate with VD. Copyright © 2016 Elsevier Inc. All rights reserved.
Erythroid Adhesion Molecules in Sickle Cell Anaemia Infants: Insights Into Early Pathophysiology.
Brousse, Valentine; Colin, Yves; Pereira, Catia; Arnaud, Cecile; Odièvre, Marie Helene; Boutemy, Anne; Guitton, Corinne; de Montalembert, Mariane; Lapouméroulie, Claudine; Picot, Julien; Le Van Kim, Caroline; El Nemer, Wassim
2015-01-01
Sickle cell anaemia (SCA) results from a single mutation in the β globin gene. It is seldom symptomatic in the first semester of life. We analysed the expression pattern of 9 adhesion molecules on red blood cells, in a cohort of 54 SCA and 17 non-SCA very young infants of comparable age (median 144 days, 81-196). Haemoglobin F (HbF) level was unsurprisingly elevated in SCA infants (41.2% ± 11.2) and 2-4 fold higher than in non-SCA infants, yet SCA infants presented significantly decreased Hb level and increased reticulocytosis. Cytometry analysis evidenced a specific expression profile on reticulocytes of SCA infants, with notably an increased expression of the adhesion molecules Lu/BCAM, ICAM-4 and LFA-3, both in percentage of positive cells and in surface density. No significant difference was found on mature red cells. Our findings demonstrate the very early onset of reticulocyte membrane modifications in SCA asymptomatic infants and allow an insight into the first pathological changes with the release of stress reticulocytes expressing a distinctive profile of adhesion molecules.
Quantifying the deformation of the red blood cell skeleton in shear flow
NASA Astrophysics Data System (ADS)
Peng, Zhangli; Zhu, Qiang
2012-02-01
To quantitatively predict the response of red blood cell (RBC) membrane in shear flow, we carried out multiphysics simulations by coupling a three-level multiscale approach of RBC membranes with a Boundary Element Method (BEM) for surrounding flows. Our multiscale approach includes a model of spectrins with the domain unfolding feature, a molecular-based model of the junctional complex with detailed protein connectivity and a whole cell Finite Element Method (FEM) model with the bilayer-skeleton friction derived from measured transmembrane protein diffusivity based on the Einstein-Stokes relation. Applying this approach, we investigated the bilayer-skeleton slip and skeleton deformation of healthy RBCs and RBCs with hereditary spherocytosis anemia during tank-treading motion. Compared with healthy cells, cells with hereditary spherocytosis anemia sustain much larger skeleton-bilayer slip and area deformation of the skeleton due to deficiency of transmembrane proteins. This leads to extremely low skeleton density and large bilayer-skeleton interaction force, both of which may cause bilayer loss. This finding suggests a possible mechanism of the development of hereditary spherocytosis anemia.
Yip, Ngai Yin; Vermaas, David A; Nijmeijer, Kitty; Elimelech, Menachem
2014-05-06
Reverse electrodialysis (RED) can harness the Gibbs free energy of mixing when fresh river water flows into the sea for sustainable power generation. In this study, we carry out a thermodynamic and energy efficiency analysis of RED power generation, and assess the membrane power density. First, we present a reversible thermodynamic model for RED and verify that the theoretical maximum extractable work in a reversible RED process is identical to the Gibbs free energy of mixing. Work extraction in an irreversible process with maximized power density using a constant-resistance load is then examined to assess the energy conversion efficiency and power density. With equal volumes of seawater and river water, energy conversion efficiency of ∼ 33-44% can be obtained in RED, while the rest is lost through dissipation in the internal resistance of the ion-exchange membrane stack. We show that imperfections in the selectivity of typical ion exchange membranes (namely, co-ion transport, osmosis, and electro-osmosis) can detrimentally lower efficiency by up to 26%, with co-ion leakage being the dominant effect. Further inspection of the power density profile during RED revealed inherent ineffectiveness toward the end of the process. By judicious early discontinuation of the controlled mixing process, the overall power density performance can be considerably enhanced by up to 7-fold, without significant compromise to the energy efficiency. Additionally, membrane resistance was found to be an important factor in determining the power densities attainable. Lastly, the performance of an RED stack was examined for different membrane conductivities and intermembrane distances simulating high performance membranes and stack design. By thoughtful selection of the operating parameters, an efficiency of ∼ 37% and an overall gross power density of 3.5 W/m(2) represent the maximum performance that can potentially be achieved in a seawater-river water RED system with low-resistance ion exchange membranes (0.5 Ω cm(2)) at very small spacing intervals (50 μm).
William C. Parker; Daniel C. Dey
2008-01-01
A field experiment was established in a secondgrowth hardwood forest dominated by red oak (Quercus rubra L.) to examine the effects of shelterwood overstory density on leaf gas exchange and seedling water status of planted red oak, naturally regenerated red oak and sugar maple (Acer saccharum Marsh.) seedlings during the first...
Fu, Jinling; Nagashima, Mikiko; Guo, Chuanyu; Raymond, Pamela A; Wei, Xiangyun
2018-01-01
Human Crb1 is implicated in some forms of retinal degeneration, suggesting a role in photoreceptor maintenance. Multiple Crumbs (Crb) polarity genes are expressed in vertebrate retina, although their functional roles are not well understood. To gain further insight into Crb and photoreceptor maintenance, we compared retinal cell densities between wild-type and Tg(RH2-2:Crb2b-sfEX/RH2-2:GFP)pt108b transgenic zebrafish, in which the extracellular domain of Crb2b-short form (Crb2b-sfEX) is expressed in the retina as a secreted protein, which disrupts the planar organization of RGB cones (red, green, and blue) by interfering with Crb2a/2b-based cone-cone adhesion. We used standard morphometric techniques to assess age-related changes in retinal cell densities in adult zebrafish (3 to 27 months old), and to assess effects of the Crb2b-sfEX transgene on retinal structure and photoreceptor densities. Linear cell densities were measured in all retinal layers in radial sections with JB4-Feulgen histology. Planar (surface) densities of cones were determined in retinal flat-mounts. Cell counts from wild-type and pt108b transgenic fish were compared with both a "photoreceptor maintenance index" and statistical analysis of cell counts. Age-related changes in retinal cell linear densities and cone photoreceptor planar densities in wild-type adult zebrafish provided a baseline for analysis. Expression of Crb2b-sfEX caused progressive and selective degeneration of RGB cones, but had no effect on ultraviolet-sensitive (UV) cones, and increased numbers of rod photoreceptors. These differential responses of RGB cones, UV cones, and rods to sustained exposure to Crb2b-sfEX suggest that Crb-based photoreceptor maintenance mechanisms are highly selective.
J. Y. Zhu; C. Tim Scott; Karen L. Scallon; Gary C. Myers
2007-01-01
This study demonstrated that average ring width (or average annual radial growth rate) is a reliable parameter to quantify the effects of tree plantation density (growth suppression) on wood density and tracheid anatomical properties. The average ring width successfully correlated wood density and tracheid anatomical properties of red pines (Pinus resinosa Ait.) from a...
Cao, Yunqing; Hu, Yongyou; Sun, Jian; Hou, Bin
2010-08-01
Microbial fuel cell (MFC) holds a great promise to harvest electricity directly from a wide range of ready degradable organic matters and enhance degradation of some recalcitrant contaminants. Glucose, acetate sodium and ethanol were separately examined as co-substrates for simultaneous bioelectricity generation and Congo red degradation in a proton exchange membrane (PEM) air-cathode single-chamber MFC. The batch test results showed that more than 98% decolorization at the dye concentration of 300 mg/L were achieved within 36 h for all tested co-substrates during electricity generation. The decolorization rate was different with the co-substrates used. The fastest decolorization rate was achieved with glucose followed by ethanol and sodium acetate. Accumulated intermediates were observed during Congo red degradation which was demonstrated by UV-Visible spectra and high performance liquid chromatography (HPLC). Electricity generation was sustained and not significantly affected by the Congo red degradation. Glucose, acetate sodium and ethanol produced maximum power densities of 103 mW/m(2), 85.9 mW/m(2) and 63.2 mW/m(2), respectively, and the maximum voltage output decreased by only 7% to 15%. Our results demonstrated the feasibility of using various co-substrates for simultaneous decolorization of Congo red and bioelectricity generation in the MFC and showed that glucose was the preferred co-substrate. Copyright (c) 2009 Elsevier B.V. All rights reserved.
Light Spectrum Related Responses of 1-g and Clino-Rotated Cress
NASA Astrophysics Data System (ADS)
Rakleviciene, D.; Svegzdiene, D.; Losinska, R.
2008-06-01
Growth and positioning of cress on a 50-rpm horizontal clinostat in response to blue (450 nm), red (660 nm) and far red (735 nm) light spectral components and their combinations (red & far red or blue & red & far red) were estimated and compared with cress grown in the usual vertical position with and without illumination. No gravity-related alterations have been determined in the elongation of dark-grown hypocotyls, though leaves slightly responded to clino-rotation. Impact of light of 450, 660 and 735 nm wavelengths applied at a comparatively low density of the photon flux (5, 13, 0.8-1 μmol m-2s-1, respectively) had a stronger inhibiting effect on the elongation of hypocotyls on clinostat than at 1 g. Growth of 1-g petioles responded to light spectrum which was not the case with clino-rotated ones. However, radial expansion of cells in palisade and spongy mesophyll tissues of clino-rotated laminas was promoted under combined blue & red & far red illumination (50 μmol·m-2s-1). Gravity-dependent alteration of the positioning of leaf petioles and laminas was suppressed by light. The obtained data confirm the interactions between responses of cress seedlings induced by changed gravity and by spectral components of light.
Adolescent intake of animal fat and red meat in relation to premenopausal mammographic density
Bertrand, Kimberly A.; Burian, Rosemarie A.; Eliassen, A. Heather; Willett, Walter C.; Tamimi, Rulla M.
2016-01-01
Purpose Adolescence is hypothesized to be a time period of particular susceptibility to breast cancer risk factors. Red meat and fat intake during high school was positively associated with risk of breast cancer among premenopausal women in the Nurses’ Health Study II (NHSII). High mammographic density is a strong predictor of breast cancer risk but there is limited research on dietary factors associated with breast density. To test the hypothesis that high intake of animal fat or red meat during adolescence is associated with mammographic density, we analyzed data from premenopausal women in the NHSII. Methods Participants recalled adolescent diet on a high school food frequency questionnaire. We assessed absolute and percent mammographic density on digitized analog film mammograms for 687 premenopausal women with no history of cancer. We used generalized linear regression to quantify associations of adolescent animal fat and red meat intake with mammographic density, adjusting for age, body mass index, and other predictors of mammographic density. Results Adolescent animal fat intake was significantly positively associated with premenopausal mammographic density, with a mean percent density of 39.2% in the lowest quartile of adolescent animal fat intake vs. 43.1% in the highest quartile (p-trend: 0.03). A non-significant positive association was also observed for adolescent red meat intake (p-trend: 0.14). Conclusions These findings suggest that higher adolescent animal fat intake is weakly associated with percent mammographic density in premenopausal women. PMID:26791521
Rejuvenation of allogenic red cells: benefits and risks.
Aujla, H; Woźniak, M; Kumar, T; Murphy, G J
2018-06-04
To review preclinical and clinical studies that have evaluated the effects of red cell rejuvenation in vivo and in vitro and to assess the potential risks and benefits from their clinical use. A systematic review and narrative synthesis of the intervention of red cell rejuvenation using a red cell processing solution containing inosine, pyruvate, phosphate and adenine. Outcomes of interest in vitro were changes in red cell characteristics including adenosine triphosphate (ATP), 2,3-diphosphoglycerate (2,3-DPG), deformability and the accumulation of oxidized lipids and other reactive species in the red cell supernatant. Outcomes in vivo were 24-h post-transfusion survival and the effects on oxygen delivery, organ function and inflammation in transfused recipients. The literature search identified 49 studies evaluating rejuvenated red cells. In vitro rejuvenation restored cellular properties including 2,3-DPG and ATP to levels similar to freshly donated red cells. In experimental models, in vivo transfusion of rejuvenated red cells improved oxygen delivery and myocardial, renal and pulmonary function when compared to stored red cells. In humans, in vivo 24-h survival of rejuvenated red cells exceeded 75%. In clinical studies, rejuvenated red cells were found to be safe, with no reported adverse effects. In one adult cardiac surgery trial, transfusion of rejuvenated red cells resulted in improved myocardial performance. Transfusion of rejuvenated red cells reduces organ injury attributable to the red cell storage lesion without adverse effects in experimental studies in vivo. The clinical benefits of this intervention remain uncertain. © 2018 International Society of Blood Transfusion.
Ring, Andrej; Langer, Stefan; Tilkorn, Daniel; Goertz, Ole; Henrich, Lena; Stricker, Ingo; Steinau, Hans-Ulrich; Steinstraesser, Lars; Hauser, Joerg
2010-09-28
Formation of encapsulating, avascular fibrous tissue is deemed to decrease implant's biocompatibility and versatility. We investigated whether plasma-mediated collagen coating possesses the ability to enhance neovascularization in the vicinity of silicone implants. Plasma-treated collagen-I-coated silicone samples were placed into the dorsal skinfold chambers of female balb/c mice (n = 10). Conventional silicone served as control (n = 10). Intravital microscopy was performed within implant's surrounding tissue on days 1, 5, and 10. Functional vessel density, intervascular distance, vessel diameter, microvascular permeability, red blood cell velocity, and leukocyte-endothelium interaction were determined. Enhanced angiogenesis in the tissue surrounding plasma-pretreated collagen-coated implants was noted. Significant increase of functional vessel density due to vascular new development was observed (t test, P < .05). Analyses of microvascular permeability and red blood cell velocity displayed stable perfusion of the vascular network neighboring the surface-modified implants. Intensified vascularity due to induced angiogenesis and neovascularization in the tissue surrounding plasma-collagen-coated samples were observed. These results indicate that plasma-mediated collagen coating might be a promising technology in order to improve the biocompatibility and versatility of silicone implants.
Ring, Andrej; Langer, Stefan; Tilkorn, Daniel; Goertz, Ole; Henrich, Lena; Stricker, Ingo; Steinau, Hans-Ulrich; Steinstraesser, Lars; Hauser, Joerg
2010-01-01
Objective: Formation of encapsulating, avascular fibrous tissue is deemed to decrease implant's biocompatibility and versatility. We investigated whether plasma-mediated collagen coating possesses the ability to enhance neovascularization in the vicinity of silicone implants. Methods: Plasma-treated collagen-I–coated silicone samples were placed into the dorsal skinfold chambers of female balb/c mice (n = 10). Conventional silicone served as control (n = 10). Intravital microscopy was performed within implant's surrounding tissue on days 1, 5, and 10. Functional vessel density, intervascular distance, vessel diameter, microvascular permeability, red blood cell velocity, and leukocyte-endothelium interaction were determined. Results: Enhanced angiogenesis in the tissue surrounding plasma-pretreated collagen-coated implants was noted. Significant increase of functional vessel density due to vascular new development was observed (t test, P < .05). Analyses of microvascular permeability and red blood cell velocity displayed stable perfusion of the vascular network neighboring the surface-modified implants. Conclusion: Intensified vascularity due to induced angiogenesis and neovascularization in the tissue surrounding plasma-collagen–coated samples were observed. These results indicate that plasma-mediated collagen coating might be a promising technology in order to improve the biocompatibility and versatility of silicone implants. PMID:20936137
21 CFR 640.10 - Red Blood Cells.
Code of Federal Regulations, 2014 CFR
2014-04-01
... ADDITIONAL STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Red Blood Cells § 640.10 Red Blood Cells. The proper name of this product shall be Red Blood Cells. The product is defined as red blood cells remaining... 21 Food and Drugs 7 2014-04-01 2014-04-01 false Red Blood Cells. 640.10 Section 640.10 Food and...
21 CFR 640.10 - Red Blood Cells.
Code of Federal Regulations, 2013 CFR
2013-04-01
... ADDITIONAL STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Red Blood Cells § 640.10 Red Blood Cells. The proper name of this product shall be Red Blood Cells. The product is defined as red blood cells remaining... 21 Food and Drugs 7 2013-04-01 2013-04-01 false Red Blood Cells. 640.10 Section 640.10 Food and...
21 CFR 640.10 - Red Blood Cells.
Code of Federal Regulations, 2011 CFR
2011-04-01
... ADDITIONAL STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Red Blood Cells § 640.10 Red Blood Cells. The proper name of this product shall be Red Blood Cells. The product is defined as red blood cells remaining... 21 Food and Drugs 7 2011-04-01 2010-04-01 true Red Blood Cells. 640.10 Section 640.10 Food and...
21 CFR 640.10 - Red Blood Cells.
Code of Federal Regulations, 2012 CFR
2012-04-01
... ADDITIONAL STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Red Blood Cells § 640.10 Red Blood Cells. The proper name of this product shall be Red Blood Cells. The product is defined as red blood cells remaining... 21 Food and Drugs 7 2012-04-01 2012-04-01 false Red Blood Cells. 640.10 Section 640.10 Food and...
21 CFR 640.10 - Red Blood Cells.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 21 Food and Drugs 7 2010-04-01 2010-04-01 false Red Blood Cells. 640.10 Section 640.10 Food and... ADDITIONAL STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Red Blood Cells § 640.10 Red Blood Cells. The proper name of this product shall be Red Blood Cells. The product is defined as red blood cells remaining...
Pigment cell mechanism of postembryonic stripe pattern formation in the Japanese four-lined snake.
Murakami, Arata; Hasegawa, Masami; Kuriyama, Takeo
2016-02-01
Postembryonic changes in the dermal and epidermal pigment cell architecture of the striped and nonstriped morph of the Japanese four-lined snake Elaphe quadrivirgata were examined to reveal stripe pattern formation after hatching. The striped and nonstriped morphs were distinguishable at the hatching, suggesting that the basis of stripe pattern was formed during embryonic development. In the striped morph, the color of stripes changed from red-brown in juveniles to vivid dark-brown in adults, and density of dermal melanophore increased much more in the stripe than background dorsal scales with growth. This increase in density of dermal melanophore was accompanied not only by the increased epidermal melanophore density but also by the change in vertical structures of dermal melanophore. By contrast, the density of epidermal and dermal melanophore evenly increased over the dorsal scales in the nonstriped morph. Thus, the increased vividness of the stripe pattern after hatching is achieved through localized increase of melanophore density particularly in the stripe region but not over the whole dorsal scales. © 2015 Wiley Periodicals, Inc.
21 CFR 864.8185 - Calibrator for red cell and white cell counting.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Calibrator for red cell and white cell counting... Calibrator for red cell and white cell counting. (a) Identification. A calibrator for red cell and white cell counting is a device that resembles red or white blood cells and that is used to set instruments intended...
Cross-species malaria immunity induced by chemically attenuated parasites
Good, Michael F.; Reiman, Jennifer M.; Rodriguez, I. Bibiana; Ito, Koichi; Yanow, Stephanie K.; El-Deeb, Ibrahim M.; Batzloff, Michael R.; Stanisic, Danielle I.; Engwerda, Christian; Spithill, Terry; Hoffman, Stephen L.; Lee, Moses; McPhun, Virginia
2013-01-01
Vaccine development for the blood stages of malaria has focused on the induction of antibodies to parasite surface antigens, most of which are highly polymorphic. An alternate strategy has evolved from observations that low-density infections can induce antibody-independent immunity to different strains. To test this strategy, we treated parasitized red blood cells from the rodent parasite Plasmodium chabaudi with seco-cyclopropyl pyrrolo indole analogs. These drugs irreversibly alkylate parasite DNA, blocking their ability to replicate. After administration in mice, DNA from the vaccine could be detected in the blood for over 110 days and a single vaccination induced profound immunity to different malaria parasite species. Immunity was mediated by CD4+ T cells and was dependent on the red blood cell membrane remaining intact. The human parasite, Plasmodium falciparum, could also be attenuated by treatment with seco-cyclopropyl pyrrolo indole analogs. These data demonstrate that vaccination with chemically attenuated parasites induces protective immunity and provide a compelling rationale for testing a blood-stage parasite-based vaccine targeting human Plasmodium species. PMID:23863622
Woźniak, Marcin J; Qureshi, Saqib; Sullo, Nikol; Dott, William; Cardigan, Rebecca; Wiltshire, Michael; Nath, Mintu; Patel, Nishith N; Kumar, Tracy; Goodall, Alison H; Murphy, Gavin J
2018-02-01
We evaluated the effects of two interventions that modify the red cell storage lesion on kidney and lung injury in experimental models of transfusion. White-landrace pigs (n = 32) were allocated to receive sham transfusion (crystalloid), 14-day stored allogeneic red cells, 14-day red cells washed using the red cells washing/salvage system (CATS; Fresenius, Germany), or 14-day red cells rejuvenated using the inosine solution (Rejuvesol solution; Zimmer Biomet, USA) and washed using the CATS device. Functional, biochemical, and histologic markers of organ injury were assessed for up to 24 h posttransfusion. Transfusion of 14 day red cells resulted in lung injury (lung injury score vs. sham, mean difference -0.3 (95% CI, -0.6 to -0.1; P = 0.02), pulmonary endothelial dysfunction, and tissue leukocyte sequestration. Mechanical washing reduced red cell-derived microvesicles but increased cell-free hemoglobin in 14-day red cell units. Transfusion of washed red cells reduced leukocyte sequestration but did not reduce the lung injury score (mean difference -0.2; 95% CI, -0.5 to 0.1; P = 0.19) relative to 14-day cells. Transfusion of washed red cells also increased endothelial activation and kidney injury. Rejuvenation restored adenosine triphosphate to that of fresh red cells and reduced microvesicle concentrations without increasing cell-free hemoglobin release. Transfusion of rejuvenated red cells reduced plasma cell-free hemoglobin, leukocyte sequestration, and endothelial dysfunction in recipients and reduced lung and kidney injury relative to 14-day or washed 14-day cells. Reversal of the red cell storage lesion by rejuvenation reduces transfusion-associated organ injury in swine.
Hao, Yan; Saygili, Yasemin; Cong, Jiayan; Eriksson, Anna; Yang, Wenxing; Zhang, Jinbao; Polanski, Enrico; Nonomura, Kazuteru; Zakeeruddin, Shaik Mohammed; Grätzel, Michael; Hagfeldt, Anders; Boschloo, Gerrit
2016-12-07
Blue and green dyes as well as NIR-absorbing dyes have attracted great interest because of their excellent ability of absorbing the incident photons in the red and near-infrared range region. A novel blue D-π-A dye (Dyenamo Blue), based on the diketopyrrolopyrrole (DPP)-core, has been designed and synthesized. Assembled with the cobalt bipyridine-based electrolytes, the device with Dyenamo Blue achieved a satisfying efficiency of 7.3% under one sun (AM1.5 G). The co-sensitization strategy was further applied on this blue organic dye together with a red D-π-A dye (D35). The successful co-sensitization outperformed a panchromatic light absorption and improved the photocurrent density; this in addition to the open-circuit potential result in an efficiency of 8.7%. The extended absorption of the sensitization and the slower recombination reaction between the blue dye and TiO 2 surface inhibited by the additional red sensitizer could be the two main reasons for the higher performance. In conclusion, from the results, the highly efficient cobalt-based DSSCs could be achieved with the co-sensitization between red and blue D-π-A organic dyes with a proper design, which showed us the possibility of applying this strategy for future high-performance solar cells.
Rheologic and hemodynamic characteristics of red cells of mouse, rat and human.
Chen, D; Kaul, D K
1994-01-01
The present study compares hematologic, rheologic and hemodynamic characteristics of red cells from mouse, rat and human. Red cells in these species are biconcave discs that show significant differences in diameter and mean corpuscular volume (MCV). However, differences in mean corpuscular hemoglobin concentration (MCHC) are not significant. Viscosity measurement of washed red cell suspensions (in each case the medium osmolarity adjusted to match plasma osmolarity) showed significant interspecies differences at shear rates of 37.5 and 750 sec-1 as follows: Human > rat > mouse. Hemodynamic and microcirculatory behavior of these red cells was investigated in the artificially perfused ex vivo mesocecum vasculature of the rat. Hemodynamic measurements in the whole ex vivo mesocecum preparation revealed maximal increase in the peripheral resistance unit (PRU) for the human red cells followed by the rat and mouse red cells, respectively at a hematocrit (Hct) of 40%. Further, measurements of red cell velocities (Vrbc) in single arterioles of the mesocecum vasculature, during sustained perfusion with washed red cell suspensions, showed that at any given perfusion pressure (Pa), Vrbc for both mouse and rat red cells was higher than that for human red cells, while Vrbc for mouse red cells was higher than that for the rat. These results demonstrate that the microvascular flow behavior of these red cells is likely to be influenced by both physical and rheologic characteristics.
Yip, Ngai Yin; Elimelech, Menachem
2014-09-16
Pressure retarded osmosis (PRO) and reverse electrodialysis (RED) are emerging membrane-based technologies that can convert chemical energy in salinity gradients to useful work. The two processes have intrinsically different working principles: controlled mixing in PRO is achieved by water permeation across salt-rejecting membranes, whereas RED is driven by ion flux across charged membranes. This study compares the energy efficiency and power density performance of PRO and RED with simulated technologically available membranes for natural, anthropogenic, and engineered salinity gradients (seawater-river water, desalination brine-wastewater, and synthetic hypersaline solutions, respectively). The analysis shows that PRO can achieve both greater efficiencies (54-56%) and higher power densities (2.4-38 W/m(2)) than RED (18-38% and 0.77-1.2 W/m(2)). The superior efficiency is attributed to the ability of PRO membranes to more effectively utilize the salinity difference to drive water permeation and better suppress the detrimental leakage of salts. On the other hand, the low conductivity of currently available ion exchange membranes impedes RED ion flux and, thus, constrains the power density. Both technologies exhibit a trade-off between efficiency and power density: employing more permeable but less selective membranes can enhance the power density, but undesired entropy production due to uncontrolled mixing increases and some efficiency is sacrificed. When the concentration difference is increased (i.e., natural → anthropogenic → engineered salinity gradients), PRO osmotic pressure difference rises proportionally but not so for RED Nernst potential, which has logarithmic dependence on the solution concentration. Because of this inherently different characteristic, RED is unable to take advantage of larger salinity gradients, whereas PRO power density is considerably enhanced. Additionally, high solution concentrations suppress the Donnan exclusion effect of the charged RED membranes, severely reducing the permselectivity and diminishing the energy conversion efficiency. This study indicates that PRO is more suitable to extract energy from a range of salinity gradients, while significant advancements in ion exchange membranes are likely necessary for RED to be competitive with PRO.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yip, NY; Elimelech, M
Pressure retarded osmosis (PRO) and reverse electrodialysis (RED) are emerging membrane-based technologies that can convert chemical energy in salinity gradients to useful work. The two processes have intrinsically different working principles: controlled mixing in PRO is achieved by water permeation across salt-rejecting membranes, whereas RED is driven by ion flux across charged membranes. This study compares the energy efficiency and power density performance of PRO and RED with simulated technologically available membranes for natural, anthropogenic, and engineered salinity gradients (seawater-river water, desalination brine-wastewater, and synthetic hypersaline solutions, respectively). The analysis shows that PRO can achieve both greater efficiencies (54-56%) andmore » higher power densities (2.4-38 W/m(2)) than RED (18-38% and 0.77-1.2 W/m(2)). The superior efficiency is attributed to the ability of PRO membranes to more effectively utilize the salinity difference to drive water permeation and better suppress the detrimental leakage of salts. On the other hand, the low conductivity of currently available ion exchange membranes impedes RED ion flux and, thus, constrains the power density. Both technologies exhibit a trade-off between efficiency and power density: employing more permeable but less selective membranes can enhance the power density, but undesired entropy production due to uncontrolled mixing increases and some efficiency is sacrificed. When the concentration difference is increased (i.e., natural -> anthropogenic -> engineered salinity gradients), PRO osmotic pressure difference rises proportionally but not so for RED Nernst potential, which has logarithmic dependence on the solution concentration. Because of this inherently different characteristic, RED is unable to take advantage of larger salinity gradients, whereas PRO power density is considerably enhanced. Additionally, high solution concentrations suppress the Donnan exclusion effect of the charged RED membranes, severely reducing the permselectivity and diminishing the energy conversion efficiency. This study indicates that PRO is more suitable to extract energy from a range of salinity gradients, while significant advancements in ion exchange membranes are likely necessary for RED to be competitive with PRO.« less
Chang, Alex L; Kim, Young; Seitz, Aaron P; Schuster, Rebecca M; Lentsch, Alex B; Pritts, Timothy A
2016-01-01
Erythrocyte-derived microparticles (MPs) are sub-micrometer, biologically active vesicles shed by red blood cells as part of the biochemical changes that occur during storage. We hypothesized that MPs from stored red blood cells would activate endothelial cells. MPs from aged murine packed red blood cells (pRBCs) were isolated and used to treat confluent layers of cultured endothelial cells. Endothelial expression of leukocyte adhesion molecules, ELAM-1 and ICAM-1, and inflammatory mediator, IL-6, were evaluated at 0.5, 6, 12, and 24 hours of treatment. Healthy C57BL/6 mice were transfused with a MP suspension and lung sections were analyzed for adhesion molecules and sequestered interstitial leukocytes. Increased levels of ELAM-1 and ICAM-1 were found on cultured endothelial cells 6 hours after MP stimulation (6.91 vs 4.07 relative fluorescent intensity, RFI, p<0.01, and 5.85 vs 3.55 RFI, p=0.01, respectively). IL-6 in cell culture supernatants was increased after 12 hours of MP stimulation compared to controls (1.24 vs 0.73 ng/ml, p=0.03). In vivo experiments demonstrated that MP injection increased ELAM-1 and ICAM-1 expression at 1 hour (18.56 vs 7.08 RFI, p<0.01, and 23.66 vs 6.87 RFI, p<0.01, respectively) and caused increased density of pulmonary interstitial leukocytes by 4 hours of treatment (69.25 vs 29.25 cells/HPF, p<0.01). This series of experiments supports our hypothesis that erythrocyte-derived MPs are able to activate pulmonary endothelium, leading to the pulmonary sequestration of leukocytes following the transfusion of stored pRBCs. PMID:27792124
In vivo studies of sickle red blood cells.
Kaul, Dhananjay K; Fabry, Mary E
2004-03-01
The defining clinical feature of sickle cell anemia is periodic occurrence of painful vasoocclusive crisis. Factors that promote trapping and sickling of red cells in the microcirculation are likely to trigger vasoocclusion. The marked red cell heterogeneity in sickle blood and abnormal adhesion of sickle red cells to vascular endothelium would be major disruptive influences. Using ex vivo and in vivo models, the authors show how to dissect the relative contribution of heterogeneous sickle red cell classes to adhesive and obstructive events. These studies revealed that (1) both rheological abnormalities and adhesion of sickle red cells contribute to their abnormal hemodynamic behavior, (2) venules are the sites of sickle cell adhesion, and (3) sickle red cell deformability plays an important role in adhesive and obstructive events. Preferential adhesion of deformable sickle red cells in postcapillary venules followed by selective trapping of dense sickle red cells could result in vasoocclusion. An updated version of this 2-step model is presented. The multifactorial nature of sickle red cell adhesion needs to be considered in designing antiadhesive therapy in vivo.
Shi, Xu; Lv, Shuang; He, Xia; Liu, Xiaomei; Sun, Meiyu; Li, Meiying; Chi, Guangfan; Li, Yulin
2016-10-01
Due to the limitations of organ donors and immune rejection in severe liver diseases, stem cell-based therapy presents a promising application for tissue repair and regeneration. As a novel cell source, mesenchymal stem cells separated from human hair follicles (HF-MSCs) are convenient to obtain and have no age limit. To date, the differentiation of HF-MSCs into hepatocytes has not been reported. In this study, we explored whether HF-MSCs and HF-MSC-derived-induced pluripotent stem cells (HF-iPS) could differentiate into hepatocytes in vitro. Flow cytometry, Oil Red O stain and Alizarin Red stain were used to identify the characteristics of HF-MSCs. The expression of liver-specific gene was detected by immunofluorescence and Quantitative Polymerase Chain Reaction. Periodic Acid-Schiff stain, Indocyanine Green stain and Low-Density Lipoprotein stain were performed to evaluate the functions of induced hepatocyte-like cells (HLCs). HF-MSCs were unable to differentiate into HLCs using previously reported procedures for MSCs from other tissues. However, HF-iPS efficiently induced the generation of HLCs that expressed hepatocyte markers and drug metabolism-related genes. HF-iPS can be used as novel and alternative cellular tools for inducing hepatocytes in vitro, simultaneously benefiting from utilizing HF-MSCs as a noninvasive and convenient cell source for reprogramming.
Red cell metabolism studies on Skylab
NASA Technical Reports Server (NTRS)
Mengel, C. E.
1977-01-01
Blood samples from Spacelab crewmembers were studied for possible environment effects on red cell components. Analysis involved peroxidation of red cell lipids, enzymes of red cell metabolism, and levels of 2,3-diphosphoglyceric acid and adenosine triphosphate. Results show that there is no evidence of lipid peroxidation, that biochemical effect known to be associated with irreversible red cell damage. Changes observed in glycolytic intermediates and enzymes cannot be directly implicated as indicating evidence of red cell damage.
Neocytolysis: physiological down-regulator of red-cell mass
NASA Technical Reports Server (NTRS)
Alfrey, C. P.; Rice, L.; Udden, M. M.; Driscoll, T. B.
1997-01-01
It is usually considered that red-cell mass is controlled by erythropoietin-driven bone marrow red-cell production, and no physiological mechanisms can shorten survival of circulating red cells. In adapting to acute plethora in microgravity, astronauts' red-cell mass falls too rapidly to be explained by diminished red-cell production. Ferrokinetics show no early decline in erythropolesis, but red cells radiolabelled 12 days before launch survive normally. Selective destruction of the youngest circulating red cells-a process we call neocytolysis-is the only plausible explanation. A fall in erythropoietin below a threshold is likely to initiate neocytolysis, probably by influencing surface-adhesion molecules. Recognition of neocytolysis will require re-examination of the pathophysiology and treatment of several blood disorders, including the anaemia of renal disease.
Two apparent glucose-6-phosphate dehydrogenase variants in normal XY males: G6PD Alabama.
Prchal, J T; Hall, K; Csepreghy, M; Lilly, M; Berkow, R; Scott, C W
1988-03-01
A six-year-old black boy who had transient hemolysis after a viral infection was found to have mildly decreased red cell glucose-6-phosphate dehydrogenase (G6PD) activity (1.25 IU/g hemoglobin). Two G6PD bands, both slightly faster than normal G6PD B, were seen on electrophoresis in both the propositus as well as in his maternal grandfather. This is an unexpected finding, since the G6PD gene is located on the long arm of the X chromosome that is subject to X-chromosome inactivation, and available evidence indicates that it is present as a single functional copy in the human genome. The obvious possibility of duplication of the X chromosome was eliminated by cytogenetic analysis with G-banding. G6PD duplication is unlikely, since peripheral blood granulocytes, platelets, and lymphocytes; cultured skin and bone marrow fibroblasts; and Epstein-Barr virus-stimulated lymphocytes yielded only a single electrophoretic band with mobility identical to the slower band seen in crude red blood cell hemolysate. Study of partially purified red blood cell hemolysate G6PD also yielded a single band with identical mobility. Kinetic studies of the enzyme in the propositus and in three generations of his family identified a unique, previously unpublished G6PD mutant that is herein designated G6PD Alabama. Red blood cells were separated by density gradient into a reticulocyte-enriched, an intermediate, and a dense, older portion. Two distinct enzyme bands were identified on electrophoresis of hemolysate from the reticulocyte-enriched portion, but not from the other two portions. It is postulated that two transcriptional products of the mutant G6PD gene exist; one with a short half-life and detectable only in young red blood cells, and another with a longer half-life present in all cells. The existence of two distinct mutant genes in the genome or a unique post-translational form of the mutant G6PD detected only in reticulocytes cannot be excluded.
Sevda, Surajbhan; Sreekrishnan, T R
2012-01-01
The aim of this study was to investigate the feasibility of using agar salt bridges for proton transport in Microbial Fuel Cells (MFC). It also tries to elucidate and effect of mediators on electricity production from wastewaters through experimentation using a simulated wastewater. In order to offset the very high cost of proton exchange membrane, salt bridges have been used in dual chamber MFCs. When the concentration of salt was varied in agar salt bridges from 1% to 10%, the volumetric power density changed from 1.71 to 84.99 mW/m(3) with a concomitant variation in power density from 0.32 to 16.02 mW/m(2). The maximum power density was observed at 5% salt concentration with 10% agar, which was accompanied by 88.41% COD reduction. In the case of methylene blue (0.01 mM) as the electron mediator, the voltage and current generation were 0.551 V and 0.47 mA, respectively. A maximum open circuit voltage of 0.718 V was seen at 0.08 mM methylene blue concentration, whereas maximum power densities of 17.59 mW/m(2) and 89.22 mW/m(3) were obtained. Different concentrations of neutral red were also tried out as mediators. A maximum open circuit voltage of 0.730 V was seen at 0.01 mM neutral red, corresponding to a power density of 12.02 mW/m(2) (volumetric power density of 60.97 mW/m(3)). Biofilm formation on the electrode surface was not observed in the presence of mediators, but was present in the absence of mediators. The results clearly demonstrated the feasibility to use agar salt bridge for proton transport and role of mediators in MFCs to generate electricity.
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.
Red Cedar Invasion Along the Missouri River, South Dakota: Cause and Consequence
NASA Astrophysics Data System (ADS)
Greene, S.; Knox, J. C.
2012-12-01
This research evaluates drivers of and ecosystem response to red cedar (Juniperus virginiana) invasion of riparian surfaces downstream of Gavin's Point Dam on the Missouri River. Gavin's Point Dam changed the downstream geomorphology and hydrology of the river and its floodplain by reducing scouring floods and flood-deposited sediment. The native cottonwood species (Populus deltoides) favors cleared surfaces with little to no competitors to establish. Now that there are infrequent erosive floods along the riparian surfaces to remove competitor seeds and seedlings, other vegetation is able to establish. Red cedar is invading the understory of established cottonwood stands and post-dam riparian surfaces. To assess reasons and spatial patterns for the recent invasion of red cedar, a stratified random sampling of soil, tree density and frequency by species, and tree age of 14 forest stands was undertaken along 59 river kilometers of riparian habitat. Soil particle size was determined using laser diffraction and tree ages were estimated from ring counts of tree cores. As an indicator of ecosystem response to invasion, we measured organic matter content in soil collected beneath red cedar and cottonwood trees at three different depths. Of 565 red cedars, only two trees were established before the dam was built. We applied a multiple regression model of red cedar density as a function of cottonwood density and percent sand (63-1000 microns in diameter) in StatPlus© statistical software. Cottonwood density and percent sand are strongly correlated with invasion of red cedar along various riparian surfaces (n = 59, R2 = 0.42, p-values < 0.05). No significant differences exist between organic matter content of soil beneath red cedar and cottonwood trees (p-value > 0.05 for all depths). These findings suggest that the dam's minimization of downstream high-stage flows opened up new habitat for red cedar to establish. Fluvial geomorphic surfaces reflect soil type and cottonwood density and, in turn, predict susceptibility of a surface to red cedar invasion. Nonetheless, soils underlying red cedar and cottonwood trees are functionally similar with regard to soil organic matter content.
Effect of plantation density on kraft pulp production from red pine (Pinus resinosa Ait.)
J.Y. Zhu; G.C. Myers
2006-01-01
Red pine (Pinus resinosa Ait.) butt logs from 38 year old research plots were used to study the effect of plantation stand density on kraft pulp production. Results indicate that plantation stand density can affect pulp yield, unrefined pulp mean fibre length, and the response of pulp fibre length to pulp refining. However, the effect of plantation stand density on...
Modulation of Gardos channel activity by cytokines in sickle erythrocytes.
Rivera, Alicia; Jarolim, Petr; Brugnara, Carlo
2002-01-01
It has recently been shown that the Gardos channel activity of mouse erythrocytes can be modified by endothelins, suggesting a functional linkage between endothelin receptors and the Gardos channel. Using (86)Rubidium ((86)Rb) influx, effects were estimated of proinflammatory molecules such as platelet activator factor (PAF), endothelin-1 (ET-1), interleukin-10 (IL-10), and regulated on activation normal T cells expressed and secreted (RANTES) on the Gardos channel activity in human normal and sickle red cells. It was found that PAF (EC(50): 15 +/- 7 nM), RANTES (EC(50), 9 +/- 6 ng/mL [1.2 +/- 0.8 nM]), IL-10 (EC(50), 11 +/- 8 ng/mL [204 +/- 148 nM]), and ET-1 (EC(50), 123 +/- 34 nM) induce a significant increase in Gardos channel activity-between 28% and 84%-over the control. In addition, these agents modify the Gardos channel affinity for internal Ca(++) (K(0.5)) by 2- to 6-fold. Biochemical evidence is provided for the presence of ET receptor subtype B in sickle and normal red cells. Furthermore, it was found that ET-1, PAF, RANTES, and IL-10 induce a significant increase in red cell density (P <.05). These data suggest that activation of the Gardos channel is functionally coupled to receptor motifs such as C-X-C (PAF), C-C (RANTES), and ET receptor subtype B. Thus, cell volume regulation or erythrocyte hydration states might be altered by activation of the Gardos channel by cytokines in vivo. The role of these mediators in promoting sickle cell dehydration in vivo is under investigation.
Use of light emitting diodes (LEDs) for enhanced lipid production in micro-algae based biofuels.
Severes, Alifha; Hegde, Shashank; D'Souza, L; Hegde, Smitha
2017-05-01
Microalgae are an alternative source for renewable energy to overcome the energy crises caused by exhaustion of fuel reserves. Algal biofuel technology demands a cost effective strategy for net profitable productivity. Inconsistent illumination intensities hinder microalgal growth. The light-utilizing efficiency of the cells is critical. Light scarcity leads to low production and high intensities cause photo-inhibition. We report effective usage of LEDs of different band wavelengths on the growth of microalgae in a closed, controlled environment to generate biomass and lipid yields. Among the different intensity and wavelengths tested. The light intensities of 500lx of blue-red combination gave maximum biomass in terms of cell density. LED of red light 220lx wavelength doubled the lipid dry weight from 30% (w/w) in white light to 60% (w/w). Thin layer lipid chromatogram demonstrated a dense and prominent spot of triacylglycerols in the red light, 220lx grown cultures. The FTIR profile indicates that different wavelength exposure did not alter the functional groups or change the chemical composition of the extracted lipids ensuring the quality of the product. We reiterate the fact that combination of red and blue LEDs is favoured over white light illumination for generation of biomass. In addition, we report an exciting finding of exposure to LEDs of red wavelength post-biomass generation lead to enhanced lipid production. This simple process doubled the lipid content harvested in 20days culture period. Copyright © 2017 Elsevier B.V. All rights reserved.
21 CFR 864.8540 - Red cell lysing reagent.
Code of Federal Regulations, 2013 CFR
2013-04-01
...) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Reagents § 864.8540 Red cell lysing reagent. (a) Identification. A red cell lysing reagent is a device used to lyse (destroy) red blood cells for... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Red cell lysing reagent. 864.8540 Section 864.8540...
21 CFR 864.8540 - Red cell lysing reagent.
Code of Federal Regulations, 2014 CFR
2014-04-01
...) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Reagents § 864.8540 Red cell lysing reagent. (a) Identification. A red cell lysing reagent is a device used to lyse (destroy) red blood cells for... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Red cell lysing reagent. 864.8540 Section 864.8540...
21 CFR 864.8540 - Red cell lysing reagent.
Code of Federal Regulations, 2012 CFR
2012-04-01
...) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Reagents § 864.8540 Red cell lysing reagent. (a) Identification. A red cell lysing reagent is a device used to lyse (destroy) red blood cells for... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Red cell lysing reagent. 864.8540 Section 864.8540...
21 CFR 864.8540 - Red cell lysing reagent.
Code of Federal Regulations, 2011 CFR
2011-04-01
...) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Reagents § 864.8540 Red cell lysing reagent. (a) Identification. A red cell lysing reagent is a device used to lyse (destroy) red blood cells for... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Red cell lysing reagent. 864.8540 Section 864.8540...
21 CFR 864.5300 - Red cell indices device.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Red cell indices device. 864.5300 Section 864.5300....5300 Red cell indices device. (a) Identification. A red cell indices device, usually part of a larger... corpuscular hemoglobin (MCH), and the mean corpuscular hemoglobin concentration (MCHC). The red cell indices...
21 CFR 864.8540 - Red cell lysing reagent.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Red cell lysing reagent. 864.8540 Section 864.8540...) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Reagents § 864.8540 Red cell lysing reagent. (a) Identification. A red cell lysing reagent is a device used to lyse (destroy) red blood cells for...
21 CFR 864.5300 - Red cell indices device.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Red cell indices device. 864.5300 Section 864.5300....5300 Red cell indices device. (a) Identification. A red cell indices device, usually part of a larger... corpuscular hemoglobin (MCH), and the mean corpuscular hemoglobin concentration (MCHC). The red cell indices...
21 CFR 864.5300 - Red cell indices device.
Code of Federal Regulations, 2012 CFR
2012-04-01
... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Red cell indices device. 864.5300 Section 864.5300....5300 Red cell indices device. (a) Identification. A red cell indices device, usually part of a larger... corpuscular hemoglobin (MCH), and the mean corpuscular hemoglobin concentration (MCHC). The red cell indices...
21 CFR 864.5300 - Red cell indices device.
Code of Federal Regulations, 2013 CFR
2013-04-01
... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Red cell indices device. 864.5300 Section 864.5300....5300 Red cell indices device. (a) Identification. A red cell indices device, usually part of a larger... corpuscular hemoglobin (MCH), and the mean corpuscular hemoglobin concentration (MCHC). The red cell indices...
21 CFR 864.5300 - Red cell indices device.
Code of Federal Regulations, 2014 CFR
2014-04-01
... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Red cell indices device. 864.5300 Section 864.5300....5300 Red cell indices device. (a) Identification. A red cell indices device, usually part of a larger... corpuscular hemoglobin (MCH), and the mean corpuscular hemoglobin concentration (MCHC). The red cell indices...
Porto, B; Fonseca, A M; Godinho, I; Arosa, F A; Porto, G
2001-12-01
The present study was designed to analyse the effect of red blood cells on T-cell proliferation and expansion. A comparative study was done in peripheral blood cell cultures stimulated with phytohemagglutinin, with or without red blood cells. The presence of red blood cells had a consistent enhancing effect on T lymphocyte proliferation, as determined by an increase in both the mitotic index and thymidine uptake. Phenotypic characterization of T cell blasts by flow cytometry revealed that, in the presence of red blood cells, expanding cells were preferentially CD8+ cells. Accordingly, proliferation of CD8+ lymphocytes from two patients with CD8+ hyperlymphocytosis was dependent on the presence of red blood cells. In contrast, proliferation of CD4+ lymphocytes from two patients with CD4+ hyperlymphocytosis was strongly inhibited by the presence of red blood cells. This is the first reported evidence that human red blood cells have an enhancing effect on the expansion of CD8+ lymphocytes in vitro.
Sawall, Yvonne; Al-Sofyani, Abdulmohsin; Banguera-Hinestroza, Eulalia; Voolstra, Christian R.
2014-01-01
Algal symbionts (zooxanthellae, genus Symbiodinium) of scleractinian corals respond strongly to temperature, nutrient and light changes. These factors vary greatly along the north-south gradient in the Red Sea and include conditions, which are outside of those typically considered optimal for coral growth. Nevertheless, coral communities thrive throughout the Red Sea, suggesting that zooxanthellae have successfully acclimatized or adapted to the harsh conditions they experience particularly in the south (high temperatures and high nutrient supply). As such, the Red Sea is a region, which may help to better understand how zooxanthellae and their coral hosts successfully acclimatize or adapt to environmental change (e.g. increased temperatures and localized eutrophication). To gain further insight into the physiology of coral symbionts in the Red Sea, we examined the abundance of dominant Symbiodinium types associated with the coral Pocillopora verrucosa, and measured Symbiodinium physiological characteristics (i.e. photosynthetic processes, cell density, pigmentation, and protein composition) along the latitudinal gradient of the Red Sea in summer and winter. Despite the strong environmental gradients from north to south, our results demonstrate that Symbiodinium microadriaticum (type A1) was the predominant species in P. verrucosa along the latitudinal gradient. Furthermore, measured physiological characteristics were found to vary more with prevailing seasonal environmental conditions than with region-specific differences, although the measured environmental parameters displayed much higher spatial than temporal variability. We conclude that our findings might present the result of long-term acclimatization or adaptation of S. microadriaticum to regionally specific conditions within the Red Sea. Of additional note, high nutrients in the South correlated with high zooxanthellae density indicating a compensation for a temperature-driven loss of photosynthetic performance, which may prove promising for the resilience of these corals under increase of temperature increase and eutrophication. PMID:25137123
Sawall, Yvonne; Al-Sofyani, Abdulmohsin; Banguera-Hinestroza, Eulalia; Voolstra, Christian R
2014-01-01
Algal symbionts (zooxanthellae, genus Symbiodinium) of scleractinian corals respond strongly to temperature, nutrient and light changes. These factors vary greatly along the north-south gradient in the Red Sea and include conditions, which are outside of those typically considered optimal for coral growth. Nevertheless, coral communities thrive throughout the Red Sea, suggesting that zooxanthellae have successfully acclimatized or adapted to the harsh conditions they experience particularly in the south (high temperatures and high nutrient supply). As such, the Red Sea is a region, which may help to better understand how zooxanthellae and their coral hosts successfully acclimatize or adapt to environmental change (e.g. increased temperatures and localized eutrophication). To gain further insight into the physiology of coral symbionts in the Red Sea, we examined the abundance of dominant Symbiodinium types associated with the coral Pocillopora verrucosa, and measured Symbiodinium physiological characteristics (i.e. photosynthetic processes, cell density, pigmentation, and protein composition) along the latitudinal gradient of the Red Sea in summer and winter. Despite the strong environmental gradients from north to south, our results demonstrate that Symbiodinium microadriaticum (type A1) was the predominant species in P. verrucosa along the latitudinal gradient. Furthermore, measured physiological characteristics were found to vary more with prevailing seasonal environmental conditions than with region-specific differences, although the measured environmental parameters displayed much higher spatial than temporal variability. We conclude that our findings might present the result of long-term acclimatization or adaptation of S. microadriaticum to regionally specific conditions within the Red Sea. Of additional note, high nutrients in the South correlated with high zooxanthellae density indicating a compensation for a temperature-driven loss of photosynthetic performance, which may prove promising for the resilience of these corals under increase of temperature increase and eutrophication.
Phosphatidylserine exposure and red cell viability in red cell aging and in hemolytic anemia.
Boas, F E; Forman, L; Beutler, E
1998-03-17
Phosphatidylserine (PS) normally localizes to the inner leaflet of cell membranes but becomes exposed in abnormal or apoptotic cells, signaling macrophages to ingest them. Along similar lines, it seemed possible that the removal of red cells from circulation because of normal aging or in hemolytic anemias might be triggered by PS exposure. To investigate the role of PS exposure in normal red cell aging, we used N-hydroxysuccinimide-biotin to tag rabbit red cells in vivo, then used phycoerythrin-streptavidin to label the biotinylated cells, and annexin V-fluorescein isothiocyanate (FITC) to detect the exposed PS. Flow cytometric analysis of these cells drawn at 10-day intervals up to 70 days after biotinylation indicated that older, biotinylated cells expose more PS. Furthermore, our data match a simple model of red cell senescence that assumes both an age-dependent destruction of senescent red cells preceded by several hours of PS exposure and a random destruction of red cells without PS exposure. By using this model, we demonstrated that the exposure of PS parallels the rate at which biotinylated red cells are removed from circulation. On the other hand, using an annexin V-FITC label and flow cytometry demonstrates that exposed PS does not cause the reduced red cell life span of patients with hemolytic anemia, with the possible exception of those with unstable hemoglobins or sickle cell anemia. Thus, in some cases PS exposure on the cell surface may signal the removal of red cells from circulation, but in other cases some other signal must trigger the sequestration of cells.
Superior survival of ex vivo cultured human reticulocytes following transfusion into mice.
Kupzig, Sabine; Parsons, Stephen F; Curnow, Elinor; Anstee, David J; Blair, Allison
2017-03-01
The generation of cultured red blood cells from stem cell sources may fill an unmet clinical need for transfusion-dependent patients, particularly in countries that lack a sufficient and safe blood supply. Cultured red blood cells were generated from human CD34 + cells from adult peripheral blood or cord blood by ex vivo expansion, and a comprehensive in vivo survival comparison with standard red cell concentrates was undertaken. Significant amplification (>10 5 -fold) was achieved using CD34 + cells from both cord blood and peripheral blood, generating high yields of enucleated cultured red blood cells. Following transfusion, higher levels of cultured red cells could be detected in the murine circulation compared to standard adult red cells. The proportions of cultured blood cells from cord or peripheral blood sources remained high 24 hours post-transfusion (82±5% and 78±9%, respectively), while standard adult blood cells declined rapidly to only 49±9% by this time. In addition, the survival time of cultured blood cells in mice was longer than that of standard adult red cells. A paired comparison of cultured blood cells and standard adult red blood cells from the same donor confirmed the enhanced in vivo survival capacity of the cultured cells. The study herein represents the first demonstration that ex vivo generated cultured red blood cells survive longer than donor red cells using an in vivo model that more closely mimics clinical transfusion. Cultured red blood cells may offer advantages for transfusion-dependent patients by reducing the number of transfusions required. Copyright© Ferrata Storti Foundation.
New Developments in Red Blood Cell Preservation Using Liquid and Freezing Procedures.
1982-04-02
restore or improve the red cell 2,3 DPG and ATP levels . Biochemically modified red blood cells may be cryopreserved for indefinite storage, or they may...salvage outdated red blood cells. However,,-ndated red blood cells are also being biochemically modified to increase’the 2,3 DPG levels to 2 to 3...restore or improve the edcell 2,3 DPG and ATP levels . Biochemically modified red blood cells iay-be cryopreserved for indefinite storage. or-thy my be
Blood volume changes. [weightlessness effects
NASA Technical Reports Server (NTRS)
Johnson, P. C.; Driscoll, T. B.; Leblance, A. D.
1974-01-01
Analysis of radionuclide volume determinations made for the crewmembers of selected Gemini and Apollo missions showed that orbital spaceflight has an effect on red cell mass. Because the methods and the protocol developed for earlier flights were used for the crews of the three Skylab missions, direct comparisons are possible. After each Skylab mission, decreases were found in crewmembers' red cell masses. The mean red cell mass decrease of 11 percent or 232 milliliters was approximately equal to the 10 percent mean red cell mass decrease of the Apollo 14 to 17 crewmembers. The red cell mass drop was greatest and the postrecovery reticulocyte response least for crewmembers of the 28-day Skylab 2 mission. Analyses of data from the red cell mass determinations indicate that the red cell mass drops occurred in the first 30 days of flight and that a gradual recovery of the red cell mass deficits began approximately 60 days after launch. The beginning of red cell mass regeneration during the Skylab 4 flight may explain the higher postmission reticulocyte counts.
Magnetic Levitation Coupled with Portable Imaging and Analysis for Disease Diagnostics.
Knowlton, Stephanie M; Yenilmez, Bekir; Amin, Reza; Tasoglu, Savas
2017-02-19
Currently, many clinical diagnostic procedures are complex, costly, inefficient, and inaccessible to a large population in the world. The requirements for specialized equipment and trained personnel require that many diagnostic tests be performed at remote, centralized clinical laboratories. Magnetic levitation is a simple yet powerful technique and can be applied to levitate cells, which are suspended in a paramagnetic solution and placed in a magnetic field, at a position determined by equilibrium between a magnetic force and a buoyancy force. Here, we present a versatile platform technology designed for point-of-care diagnostics which uses magnetic levitation coupled to microscopic imaging and automated analysis to determine the density distribution of a patient's cells as a useful diagnostic indicator. We present two platforms operating on this principle: (i) a smartphone-compatible version of the technology, where the built-in smartphone camera is used to image cells in the magnetic field and a smartphone application processes the images and to measures the density distribution of the cells and (ii) a self-contained version where a camera board is used to capture images and an embedded processing unit with attached thin-film-transistor (TFT) screen measures and displays the results. Demonstrated applications include: (i) measuring the altered distribution of a cell population with a disease phenotype compared to a healthy phenotype, which is applied to sickle cell disease diagnosis, and (ii) separation of different cell types based on their characteristic densities, which is applied to separate white blood cells from red blood cells for white blood cell cytometry. These applications, as well as future extensions of the essential density-based measurements enabled by this portable, user-friendly platform technology, will significantly enhance disease diagnostic capabilities at the point of care.
J. Y. Zhu; C. T. Scott; K. L. Scallon; G. C. Myers
2006-01-01
This study demonstrated that average ring width (or average annual radial growth rate) is a reliable parameter to quantify the effects of tree plantation ndensity (growth suppression) on wood density and tracheid anatomical properties. The average ring width successfully correlated wood density and tracheid anatomical properties of red pines (Pinus resinosa Ait.) from...
Thermal and active fluctuations of a compressible bilayer vesicle
NASA Astrophysics Data System (ADS)
Sachin Krishnan, T. V.; Yasuda, Kento; Okamoto, Ryuichi; Komura, Shigeyuki
2018-05-01
We discuss thermal and active fluctuations of a compressible bilayer vesicle by using the results of hydrodynamic theory for vesicles. Coupled Langevin equations for the membrane deformation and the density fields are employed to calculate the power spectral density matrix of membrane fluctuations. Thermal contribution is obtained by means of the fluctuation dissipation theorem, whereas active contribution is calculated from exponentially decaying time correlation functions of active random forces. We obtain the total power spectral density as a sum of thermal and active contributions. An apparent response function is further calculated in order to compare with the recent microrheology experiment on red blood cells. An enhanced response is predicted in the low-frequency regime for non-thermal active fluctuations.
Narayanan, S; Orton, S; Leparc, G F; Garcia-Rubio, L H; Potter, R L
1999-10-01
A new blood typing technology based on ultraviolet (UV) and visible light spectroscopy (UV/visible spectroscopy) has been developed. Blood groups and types are determined by quantifying reproducible changes in the UV and visible light spectra of blood in the presence of agglutinating antibodies. Samples of red cells in the presence and absence of agglutinating antibodies were examined by UV/visible spectroscopy. Blood groups and types were determined by comparing the optical density spectra obtained between 665 and 1000 nm. These comparisons generate numbers (agglutination index) ranging from 0 to 100, with smaller numbers corresponding to lack of agglutination and larger numbers corresponding to agglutination. The optical density of agglutinated blood is dramatically different from that of unagglutinated blood. The agglutination index derived from the relative slopes of the spectra is an objective indicator of agglutination strength. An agglutination index greater than 17 consistently and accurately established blood group- and type-specific agglutination. The method accurately predicted A, B, and O blood groups, and D type in over 275 samples. Scattering theory-based calculations of relative volumes of red cells before and after agglutination show a direct correlation with the agglutination index and provide the theoretical basis of the analysis. This quantitative technique is reproducible and has the potential for automation.
Cho, Eun Seob; Moon, Seong Yong; Shu, Young Sang; Hwang, Jae Dong; Youn, Seok Hyun
2015-09-01
Cochlodinium polykrikoides Margalef produces annual massive blooms in Korean coastal waters which cause great damage to aquaculture and fisheries. Although various methods have been developed to remove the red tide of C. polykrikoides, release of yellow loess has been regarded as the most desirable technique for mitigation for over 10 years. Each August, strong irradiation generates water column stratification separating warm surface from colder bottom waters. Water from a distance of 0 (St. 1), 5 (St. 2), 10 (St. 3), and 15 m (St. 4) was pumped by running a pump for 0, 10, 30 and 90 min and characterized water temperature, salinity collected, suspended solids, Chl-a, and phytoplankton including C. polykrikoides. After running for 30 min, was temperature and salinity in surface water was similar to those of bottom water, and water column stratification completely reversed after 90 min. Likewise, suspended solids, Chl-a, and total phytoplankton cell density decreased after 30 min, but C. polykrikoides did not show strong removal because of low cell density during sampling. However, the number of C. polykrikoides was significantly diluted (80%) after 90 min. These results suggested that pumping device was as an environmentally-friendly method convenient to be install in fish cages and effective to remove C. polykrikoides stratified water column conditions.
Investigation of photobiomodulation potentiality by 635 and 809 nm lasers on human osteoblasts.
Bölükbaşı Ateş, Gamze; Ak Can, Ayşe; Gülsoy, Murat
2017-04-01
Photobiomodulation (PBM) describes light-induced photochemical reactions achieved by the application of red or near infrared lasers/LED light with low energy densities. This noninvasive and painless method has been used in some clinical areas but controversial outcomes demand a skeptical look for its promising and potential effects. In this detailed in vitro study, the osteoblast cells were irradiated with 635 and 809 nm diode lasers at energy densities of 0.5, 1, and 2 J/cm 2 . Cell viability, proliferation, bone formation, and osteoblast differentiation were evaluated by methylthiazole tetrazolium (MTT) assay, Alamar Blue assay, acridine orange/propidium iodide staining, alkaline phosphatase (ALP) activity, Alizarin red staining, and reverse-transcription polymerase chain reaction (RT-PCR) to test the expression of collagen type I, ALPL, and osteocalcin. The results indicate that studied energy doses have a transient effect (48 h after laser irradiation) on the osteoblast viability and proliferation. Similarly, laser irradiation did not appear to have any effect on ALP activity. These results were confirmed by RT-PCR analysis of osteoblast markers. This study suggests that several irradiation parameters and variations in the methods should be clearly established in the laboratory before laser treatment becomes a postulated application for bone tissue regeneration in clinical level.
Red blood cells in sports: effects of exercise and training on oxygen supply by red blood cells
Mairbäurl, Heimo
2013-01-01
During exercise the cardiovascular system has to warrant substrate supply to working muscle. The main function of red blood cells in exercise is the transport of O2 from the lungs to the tissues and the delivery of metabolically produced CO2 to the lungs for expiration. Hemoglobin also contributes to the blood's buffering capacity, and ATP and NO release from red blood cells contributes to vasodilation and improved blood flow to working muscle. These functions require adequate amounts of red blood cells in circulation. Trained athletes, particularly in endurance sports, have a decreased hematocrit, which is sometimes called “sports anemia.” This is not anemia in a clinical sense, because athletes have in fact an increased total mass of red blood cells and hemoglobin in circulation relative to sedentary individuals. The slight decrease in hematocrit by training is brought about by an increased plasma volume (PV). The mechanisms that increase total red blood cell mass by training are not understood fully. Despite stimulated erythropoiesis, exercise can decrease the red blood cell mass by intravascular hemolysis mainly of senescent red blood cells, which is caused by mechanical rupture when red blood cells pass through capillaries in contracting muscles, and by compression of red cells e.g., in foot soles during running or in hand palms in weightlifters. Together, these adjustments cause a decrease in the average age of the population of circulating red blood cells in trained athletes. These younger red cells are characterized by improved oxygen release and deformability, both of which also improve tissue oxygen supply during exercise. PMID:24273518
Destruction of newly released red blood cells in space flight
NASA Technical Reports Server (NTRS)
Alfrey, C. P.; Udden, M. M.; Huntoon, C. L.; Driscoll, T.
1996-01-01
Space flight results in a rapid change in total blood volume, plasma volume, and red blood cell mass because the space to contain blood is decreased. The plasma volume and total blood volume decreases during the first hours in space and remain at a decreased level for the remainder of the flight. During the first several hours following return to earth, plasma volume and total blood volume increase to preflight levels. During the first few days in space recently produced red blood cells disappear from the blood resulting in a decrease in red blood cell mass of 10-15%. Red cells 12 d old or older survive normally and production of new cells continues at near preflight levels. After the first few days in space, the red cell mass is stable at the decreased level. Following return to earth the hemoglobin and red blood cell mass concentrations decrease reflecting the increase in plasma volume. The erythropoietin levels increase responding to "postflight anemia"; red cell production increases, and the red cell mass is restored to preflight levels after several weeks.
Stochastic nature and red cell population distribution of the sickling-induced Ca2+ permeability.
Lew, V L; Ortiz, O E; Bookchin, R M
1997-06-01
To explore basic properties of the sickling-induced cation permeability pathway, the Ca2+ component (Psickle-Ca) was studied in density-fractionated sickle cell anemia (SS) discocytes through its effects on the activity of the cells' Ca2+sensitive K+-channels (KCa). The instant state of KCa channel activation was monitored during continuous or cyclic deoxygenation of the cells using a novel thiocyanate-densecell formation method. Each deoxy pulse caused a reversible, sustained Psickle-Ca, which activated KCa channels in only 10-45% of cells at physiological [Ca2+]o ("activated cells"). After removal of cells activated by each previous deoxy pulse, subsequent pulses generated similar activated cell fractions, indicating a random determination rather than the response of a specific vulnerable subpopulation. The fraction of activated cells rose monotonically with [Ca2+]o along a curve reflecting the cells' distribution of Psickle-Ca, with values high enough in a small cell fraction to trigger near-maximal KCa channels. Consistent with the stochastic nature of Psickle-Ca, repeated deoxygenated-oxygenated pulsing led to progressive dense cell formation, whereas single long pulses caused one early density shift. Thus deoxygenation-induced Ca2+-permeabilization in SS cells is a probabilistic event with large cumulative dehydrating potential. The possible molecular nature of Psickle-Ca is discussed.
Rijnaarts, Timon; Huerta, Elisa; van Baak, Willem; Nijmeijer, Kitty
2017-11-07
Reverse electrodialysis (RED) is a membrane-based renewable energy technology that can harvest energy from salinity gradients. The anticipated feed streams are natural river and seawater, both of which contain not only monovalent ions but also divalent ions. However, RED using feed streams containing divalent ions experiences lower power densities because of both uphill transport and increased membrane resistance. In this study, we investigate the effects of divalent cations (Mg 2+ and Ca 2+ ) on RED and demonstrate the mitigation of those effects using both novel and existing commercial cation exchange membranes (CEMs). Monovalent-selective Neosepta CMS is known to block divalent cations transport and can therefore mitigate reductions in stack voltage. The new multivalent-permeable Fuji T1 is able to transport divalent cations without a major increase in resistance. Both strategies significantly improve power densities compared to standard-grade CEMs when performing RED using streams containing divalent cations.
Phosphate Ion Exchange Resin Used in the Liquid Preservation of Baboon Red Blood Cells.
1982-06-08
absence of resin. The addition of a phosphate anion exchange resin to the CPD anticoagulant provided better maintenance of red cell 23 DPG and P50 levels ...than red blood cells S.prepared from blood without resin. Red blood cell ATP levels and 24-hour post- transfusion survival values were similar whether or...coagulant provided better maintenance of red cell 2,3 DPG and P50 levels during storage of whole blood at 4 C, and red blood cells prepared from whole
21 CFR 864.8185 - Calibrator for red cell and white cell counting.
Code of Federal Regulations, 2014 CFR
2014-04-01
... counting is a device that resembles red or white blood cells and that is used to set instruments intended to count red cells, white cells, or both. It is a suspension of particles or cells whose size, shape... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Calibrator for red cell and white cell counting...
21 CFR 864.8185 - Calibrator for red cell and white cell counting.
Code of Federal Regulations, 2012 CFR
2012-04-01
... counting is a device that resembles red or white blood cells and that is used to set instruments intended to count red cells, white cells, or both. It is a suspension of particles or cells whose size, shape... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Calibrator for red cell and white cell counting...
21 CFR 864.8185 - Calibrator for red cell and white cell counting.
Code of Federal Regulations, 2011 CFR
2011-04-01
... counting is a device that resembles red or white blood cells and that is used to set instruments intended to count red cells, white cells, or both. It is a suspension of particles or cells whose size, shape... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Calibrator for red cell and white cell counting...
21 CFR 864.8185 - Calibrator for red cell and white cell counting.
Code of Federal Regulations, 2013 CFR
2013-04-01
... counting is a device that resembles red or white blood cells and that is used to set instruments intended to count red cells, white cells, or both. It is a suspension of particles or cells whose size, shape... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Calibrator for red cell and white cell counting...
Growth and replication of red rain cells at 121°C and their red fluorescence
NASA Astrophysics Data System (ADS)
Gangappa, Rajkumar; Wickramasinghe, Chandra; Wainwright, Milton; Kumar, A. Santhosh; Louis, Godfrey
2010-09-01
We have shown that the red cells found in the Red Rain (which fell on Kerala, India, in 2001) survive and grow after incubation for periods of up to two hours at 121°C . Under these conditions daughter cells appear within the original mother cells and the number of cells in the samples increases with length of exposure to 121°C. No such increase in cells occurs at room temperature, suggesting that the increase in daughter cells is brought about by exposure of the Red Rain cells to high temperatures. This is an independent confirmation of results reported earlier by two of the present authors, claiming that the cells can replicate under high pressure at temperatures upto 300°C. The flourescence behaviour of the red cells is shown to be in remarkable correspondence with the extended red emission observed in the Red Rectagle planetary nebula and other galactic and extragalactic dust clouds, suggesting, though not proving an extraterrestrial origin.
The Isolation and Partial Characterization of a Membrane Fraction Containing Phytochrome 12
Marmé, Dieter; Mackenzie, John M.; Boisard, Jean; Briggs, Winslow R.
1974-01-01
If 4-day-old dark-grown zucchini squash seedlings (Cucurbita pepo L. cv. Black Beauty) are exposed briefly to red light, subsequent cell fractionation yields about 40% of the total extractable phytochrome in the far red-absorbing form bound to a particulate fraction. The amount of far red-absorbing phytochrome in the pellet is strongly dependent on the Mg concentration in the extraction medium. The apparent density of the Pfr-containing particles following sedimentation on sucrose gradients corresponds to 15% (w/w) sucrose with 0.1 mm Mg and 40% sucrose with 10 mm Mg. This particulate fraction could be readily separated from mitochondria and other particulate material by taking advantage of these apparent density changes with changes in Mg concentration. Electron microscopy of negatively stained preparations shows that with 1 mm Mg only minute particles are present. These were too small to reveal structural detail with this technique. With 3 mm Mg, separate membranous vesicles between 400 and 600 Ångstroms in diameter appear. At higher Mg concentrations, the vesicles aggregate, causing obvious turbity. The effect of Mg on vesicle formation and aggregation is completely reversible. Above 10 mm Mg, vesicle aggregation persists, but the percentage of bound Pfr decreases. Images PMID:16658871
Alterations of red blood cell sodium transport during malarial infection
Dunn, Michael J.
1969-01-01
Previous studies have suggested that malaria induces changes in erythrocytic membrane permeability and susceptibility to osmotic lysis. The present study investigated erythrocytic transport of sodium with cells from Rhesus monkeys infected with Plasmodium knowlesi. Red blood cell sodium concentration was significantly elevated in 37 parasitized animals (21.8±1.2 mM; mean ±SEM), as compared to 23 control animals (10.0±0.38 mM). The cellular sodium increased with the density of parasitemia and the cellular potassium decreased in proportion to the elevation of sodium. Nonparasitized as well as parasitized erythrocytes possessed this abnormality of cation metabolism. Effective chloroquine therapy reversed the changes over a period of 4 days. Active sodium outflux rate constants were depressed in animals with malaria (0.202±0.012), as compared to controls (0.325±0.027). Passive sodium influx rate constants were higher in infected monkeys (0.028±0.002) than in control animals (0.019±0.002). The cross incubation of malarial plasma with normal red blood cells induced a 22% diminution in active sodium outflux but no changes were observed in sodium influx. It is concluded that malaria alters erythrocytic sodium transport in all erythrocytes. The elevated intracellular sodium concentration is the net result of decreased sodium outflux and increased sodium influx. The plasmodium organism or the affected host may produce a circulating substance that is deleterious to erythrocytic membrane cation transport. PMID:4975361
Malerba, Martino E; Heimann, Kirsten; Connolly, Sean R
2016-09-07
Ecologists have often used indirect proxies to represent variables that are difficult or impossible to measure directly. In phytoplankton, the internal concentration of the most limiting nutrient in a cell determines its growth rate. However, directly measuring the concentration of nutrients within cells is inaccurate, expensive, destructive, and time-consuming, substantially impairing our ability to model growth rates in nutrient-limited phytoplankton populations. The red chlorophyll autofluorescence (hereafter "red fluorescence") signal emitted by a cell is highly correlated with nitrogen quota in nitrogen-limited phytoplankton species. The aim of this study was to evaluate the reliability of including flow cytometric red fluorescence as a proxy for internal nitrogen status to model phytoplankton growth rates. To this end, we used the classic Quota model and designed three approaches to calibrate its model parameters to data: where empirical observations on cell internal nitrogen quota were used to fit the model ("Nitrogen-Quota approach"), where quota dynamics were inferred only from changes in medium nutrient depletion and population density ("Virtual-Quota approach"), or where red fluorescence emission of a cell was used as an indirect proxy for its internal nitrogen quota ("Fluorescence-Quota approach"). Two separate analyses were carried out. In the first analysis, stochastic model simulations were parameterized from published empirical relationships and used to generate dynamics of phytoplankton communities reared under nitrogen-limited conditions. Quota models were fitted to the dynamics of each simulated species with the three different approaches and the performance of each model was compared. In the second analysis, we fit Quota models to laboratory time-series and we calculate the ability of each calibration approach to describe the observed trajectories of internal nitrogen quota in the culture. Results from both analyses concluded that the Fluorescence-Quota approach including per-cell red fluorescence as a proxy of internal nitrogen substantially improved the ability of Quota models to describe phytoplankton dynamics, while still accounting for the biologically important process of cell nitrogen storage. More broadly, many population models in ecology implicitly recognize the importance of accounting for storage mechanisms to describe the dynamics of individual organisms. Hence, the approach documented here with phytoplankton dynamics may also be useful for evaluating the potential of indirect proxies in other ecological systems. Copyright © 2016 Elsevier Ltd. All rights reserved.
LPS-induced microvascular leukocytosis can be assessed by blue-field entoptic phenomenon.
Kolodjaschna, Julia; Berisha, Fatmire; Lung, Solveig; Schaller, Georg; Polska, Elzbieta; Jilma, Bernd; Wolzt, Michael; Schmetterer, Leopold
2004-08-01
Administration of low doses of Escherichia coli endotoxin [a lipopolysaccharide (LPS)] to humans enables the study of inflammatory mechanisms. The purpose of the present study was to investigate whether the blue-field entoptic technique may be used to quantify the increase in circulating leukocytes in the ocular microvasculature after LPS infusion. In addition, combined laser Doppler velocimetry and retinal vessel size measurement were used to study red blood cell movement. Twelve healthy male volunteers received 20 IU/kg iv LPS as a bolus infusion. Outcome parameters were measured at baseline and 4 h after LPS administration. In the first protocol (n = 6 subjects), ocular hemodynamic effects were assessed with the blue-field entoptic technique, the retinal vessel analyzer, and laser Doppler velocimetry. In the second protocol (n = 6 subjects), white blood cell (WBC) counts from peripheral blood samples and blue-field entoptic technique measurements were performed. LPS caused peripheral blood leukocytosis and increased WBC density in ocular microvessels (by 49%; P = 0.036) but did not change WBC velocity. In addition, retinal venous diameter was increased (by 9%; P = 0.008), but red blood cell velocity remained unchanged. The LPS-induced changes in retinal WBC density and leukocyte counts were significantly correlated (r = 0.87). The present study indicates that the blue-field entoptic technique can be used to assess microvascular leukocyte recruitment in vivo. In addition, our data indicate retinal venous dilation in response to endotoxin.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Moen, Scott T.; Hatcher, Christopher L.; Singh, Anup K.
We present a miniaturized centrifugal platform that uses density centrifugation for separation and analysis of biological components in small volume samples (~5 μL). We demonstrate the ability to enrich leukocytes for on-disk visualization via microscopy, as well as recovery of viable cells from each of the gradient partitions. In addition, we simplified the traditional Modified Wright-Giemsa staining by decreasing the time, volume, and expertise involved in the procedure. From a whole blood sample, we were able to extract 95.15% of leukocytes while excluding 99.8% of red blood cells. Furthermore, this platform has great potential in both medical diagnostics and researchmore » applications as it offers a simpler, automated, and inexpensive method for biological sample separation, analysis, and downstream culturing.« less
Moen, Scott T.; Hatcher, Christopher L.; Singh, Anup K.
2016-04-07
We present a miniaturized centrifugal platform that uses density centrifugation for separation and analysis of biological components in small volume samples (~5 μL). We demonstrate the ability to enrich leukocytes for on-disk visualization via microscopy, as well as recovery of viable cells from each of the gradient partitions. In addition, we simplified the traditional Modified Wright-Giemsa staining by decreasing the time, volume, and expertise involved in the procedure. From a whole blood sample, we were able to extract 95.15% of leukocytes while excluding 99.8% of red blood cells. Furthermore, this platform has great potential in both medical diagnostics and researchmore » applications as it offers a simpler, automated, and inexpensive method for biological sample separation, analysis, and downstream culturing.« less
21 CFR 660.30 - Reagent Red Blood Cells.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 21 Food and Drugs 7 2011-04-01 2010-04-01 true Reagent Red Blood Cells. 660.30 Section 660.30 Food... ADDITIONAL STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Reagent Red Blood Cells § 660.30 Reagent Red Blood Cells. (a) Proper name and definition. The proper name of the product shall be Reagent Red...
Gary A. Ritchie; James Keeley; Barbara J. Bond
2007-01-01
Coastal Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) seedlings, when planted in a reforestation setting, exhibit early height and diameter growth that is inversely proportional to planting density. One hypothesis to explain this observation is that they are able to detect the presence of nearby trees using phytochrome by sensing the ratio of...
Altered expression of blood group A and H antigens on red cells from an acute leukemic patient.
Matsuki, T; Shimano, S; Furukawa, K
1992-01-01
Alternate expressions of the blood group A and H antigens on red cells are described in a patient with acute myelocytic leukemia. The patient's red cells showed mixed field agglutination with anti-A and anti-H sera and lectins, and no agglutination with anti-B serum. The agglutinability of the A red cells with Dolichos biflorus lectin was between A1 and A2 (A intermediate). Inagglutinable red cells were separated with anti-A agglutinin, and the proportion was about 80% of total cells. The agglutinating activity with Ulex europaeus anti-H of red cells, which were inagglutinable with anti-A, was 16 times weaker than that of group O cells. The weaker reaction with Ricinus communis lectin and the stronger reaction with Psathyrella velutina lectin on the inagglutinable cells with anti-A than those on the group O cells suggest that fucosyl alpha (1-2) and galactosyl beta (1-4) residues at the nonreducing end of carbohydrate chains of H antigens on the red cells were diminished, and N-acetylglucosaminyl beta (1-3) residues were sequentially exposed. His saliva contained A and H substances in normal amounts of a secretor. Serum alpha-N-acetylgalactosaminyltransferase activity which converts O red cells to A red cells was the same as those in sera from A1 individuals. These results suggest that the synthesis of H precursors is partially blocked in this patient's red cells.
Increased phytochrome B alleviates density effects on tuber yield of field potato crops.
Boccalandro, Hernán E; Ploschuk, Edmundo L; Yanovsky, Marcelo J; Sánchez, Rodolfo A; Gatz, Christiane; Casal, Jorge J
2003-12-01
The possibility that reduced photomorphogenic responses could increase field crop yield has been suggested often, but experimental support is still lacking. Here, we report that ectopic expression of the Arabidopsis PHYB (phytochrome B) gene, a photoreceptor involved in detecting red to far-red light ratio associated with plant density, can increase tuber yield in field-grown transgenic potato (Solanum tuberosum) crops. Surprisingly, this effect was larger at very high densities, despite the intense reduction in the red to far-red light ratios and the concomitant narrowed differences in active phytochrome B levels between wild type and transgenics at these densities. Increased PHYB expression not only altered the ability of plants to respond to light signals, but they also modified the light environment itself. This combination resulted in larger effects of enhanced PHYB expression on tuber number and crop photosynthesis at high planting densities. The PHYB transgenics showed higher maximum photosynthesis in leaves of all strata of the canopy, and this effect was largely due to increased leaf stomatal conductance. We propose that enhanced PHYB expression could be used in breeding programs to shift optimum planting densities to higher levels.
Red Blood Cell Susceptibility to Pneumolysin
Bokori-Brown, Monika; Petrov, Peter G.; Khafaji, Mawya A.; Mughal, Muhammad K.; Naylor, Claire E.; Shore, Angela C.; Gooding, Kim M.; Casanova, Francesco; Mitchell, Tim J.; Titball, Richard W.; Winlove, C. Peter
2016-01-01
This study investigated the effect of the biochemical and biophysical properties of the plasma membrane as well as membrane morphology on the susceptibility of human red blood cells to the cholesterol-dependent cytolysin pneumolysin, a key virulence factor of Streptococcus pneumoniae, using single cell studies. We show a correlation between the physical properties of the membrane (bending rigidity and surface and dipole electrostatic potentials) and the susceptibility of red blood cells to pneumolysin-induced hemolysis. We demonstrate that biochemical modifications of the membrane induced by oxidative stress, lipid scrambling, and artificial cell aging modulate the cell response to the toxin. We provide evidence that the diversity of response to pneumolysin in diabetic red blood cells correlates with levels of glycated hemoglobin and that the mechanical properties of the red blood cell plasma membrane are altered in diabetes. Finally, we show that diabetic red blood cells are more resistant to pneumolysin and the related toxin perfringolysin O relative to healthy red blood cells. Taken together, these studies indicate that the diversity of cell response to pneumolysin within a population of human red blood cells is influenced by the biophysical and biochemical status of the plasma membrane and the chemical and/or oxidative stress pre-history of the cell. PMID:26984406
Etzion, Z; Tiffert, T; Bookchin, R M; Lew, V L
1993-11-01
Elevated [Ca2+]i in deoxygenated sickle cell anemia (SS) red cells (RBCs) could trigger a major dehydration pathway via the Ca(2+)-sensitive K+ channel. But apart from an increase in calcium permeability, the effects of deoxygenation on the Ca2+ metabolism of sickle cells have not been previously documented. With the application of 45Ca(2+)-tracer flux methods and the combined use of the ionophore A23187, Co2+ ions, and intracellular incorporation of the Ca2+ chelator benz-2, in density-fractionated SS RBCs, we show here for the first time that upon deoxygenation, the mean [Ca2+]i level of SS discocytes was significantly increased, two- to threefold, from a normal range of 9.4 to 11.4 nM in the oxygenated cells, to a range of 21.8 to 31.7 nM in the deoxygenated cells, closer to K+ channel activatory levels. Unlike normal RBCs, deoxygenated SS RBCs showed a two- to fourfold increase in pump-leak Ca2+ turnover. Deoxygenation of the SS RBCs reduced their Ca2+ pump Vmax, more so in reticulocyte- and discocyte-rich than in dense cell fractions, and decreased their cytoplasmic Ca2+ buffering. Analysis of these results suggests that both increased Ca2+ influx and reduced Ca2+ pump extrusion contribute to the [Ca2+]i elevation.
White, A. P.; Gibson, D. L.; Grassl, G. A.; Kay, W. W.; Finlay, B. B.; Vallance, B. A.; Surette, M. G.
2008-01-01
The Salmonella rdar (red, dry, and rough) morphotype is an aggregative and resistant physiology that has been linked to survival in nutrient-limited environments. Growth of Salmonella enterica serovar Typhimurium was analyzed in a variety of nutrient-limiting conditions to determine whether aggregation would occur at low cell densities and whether the rdar morphotype was involved in this process. The resulting cultures consisted of two populations of cells, aggregated and nonaggregated, with the aggregated cells preferentially displaying rdar morphotype gene expression. The two groups of cells could be separated based on the principle that aggregated cells were producing greater amounts of thin aggregative fimbriae (Tafi or curli). In addition, the aggregated cells retained some physiological characteristics of the rdar morphotype, such as increased resistance to sodium hypochlorite. Competitive infection experiments in mice showed that nonaggregative ΔagfA cells outcompeted rdar-positive wild-type cells in all tissues analyzed, indicating that aggregation via the rdar morphotype was not a virulence adaptation in Salmonella enterica serovar Typhimurium. Furthermore, in vivo imaging experiments showed that Tafi genes were not expressed during infection but were expressed once Salmonella was passed out of the mice into the feces. We hypothesize that the primary role of the rdar morphotype is to enhance Salmonella survival outside the host, thereby aiding in transmission. PMID:18195033
NASA Astrophysics Data System (ADS)
Chai, Shiqiang; Guo, Yu; Zhang, Zhenyu; Chai, Zhen; Ma, Yurong; Qi, Limin
2017-04-01
Long wavelength light-responsive drug delivery systems based on mesoporous silica nanoparticles (MSNs) have attracted much attention in the last few years. In this paper, a red light (660 nm)-responsive drug delivery system based on low-cost cyclodextrin (CD)-gated MSNs containing a photodynamic therapy (PDT) photosensitizer (Chlorin e6, Ce6) was developed for the first time. The drug release experiment in water demonstrated that with the irradiation of red light, Ce6 can be excited to generate singlet oxygen, which can further cleave the singlet oxygen sensitive linker to trigger the departure of CD and the release of cargo. Further in vitro release experiments confirmed that cargo can be released from MSNs with the irradiation of red light and spread into the entire cell. The relative low power density (0.5 W cm-2) of excitation light together with the short irradiation time (one-three min) result in a low light dose (30-90 J cm-2) for the drug delivery, contributing to their potential clinical applications.
Schmidt, Robert L; Mock, Donald M; Franco, Robert S; Cohen, Robert M; North, Anne K; Cancelas, José A; Geisen, Christof; Strauss, Ronald G; Vlaar, Alexander P; Nalbant, Demet; Widness, John A
2017-06-01
Biotin-labeled red blood cells (BioRBCs) are used for in vivo kinetic studies. Because BioRBC dosing occasionally induces antibodies, a sensitive and specific anti-BioRBC detection assay is needed. Aims were to 1) develop a gel card assay to evaluate existing, naturally occurring and BioRBC-induced plasma antibodies, 2) compare gel card and tube agglutination detection results, and 3) test for a relationship of antibody induction and BioRBC dose. Reagent BioRBCs were prepared using sulfo-NHS biotin ranging from densities 18 (BioRBC-18) to 1458 (BioRBC-1458) µg/mL RBCs. Among BioRBC-exposed subjects, gel card and tube agglutination results were concordant in 21 of 22 adults and all 19 infant plasma samples. Gel card antibody detection sensitivity was more than 10-fold greater than tube agglutination. Twelve to 16 weeks after BioRBC exposure, induced anti-antibodies were detected by gel card in three of 26 adults (12%) at reagent densities BioRBC-256 or less, but in none of 41 infants. Importantly, induced anti-BioRBC antibodies were associated with higher BioRBC dose (p = 0.008); no antibodies were detected in 18 subjects who received BioRBC doses less than or equal to BioRBC-18. For noninduced BioRBC antibodies, six of 1125 naïve adults (0.3%) and none of 46 naïve infants demonstrated existing anti-BioRBC antibodies using reagent BioRBC-140 or -162. Existing anti-BioRBCs were all neutralized by biotin compounds, while induced antibodies were not. The gel card assay is more sensitive than the tube agglutination assay. We recommend reagent BioRBC-256 for identifying anti-BioRBCs. Use of a low total RBC biotin label dose (≤ BioRBC-18) may minimize antibody induction. © 2017 AABB.
Wine as a biological fluid: history, production, and role in disease prevention.
Soleas, G J; Diamandis, E P; Goldberg, D M
1997-01-01
Wine has been part of human culture for 6,000 years, serving dietary and socio-religious functions. Its production takes place on every continent, and its chemical composition is profoundly influenced by enological techniques, the grape cultivar from which it originates, and climatic factors. In addition to ethanol, which in moderate consumption can reduce mortality from coronary heart disease by increasing high-density lipoprotein cholesterol and inhibiting platelet aggregation, wine (especially red wine) contains a range of polyphenols that have desirable biological properties. These include the phenolic acids (p-coumaric, cinnamic, caffeic, gentisic, ferulic, and vanillic acids), trihydroxy stilbenes (resveratrol and polydatin), and flavonoids (catechin, epicatechin, and quercetin). They are synthesized by a common pathway from phenylalanine involving polyketide condensation reactions. Metabolic regulation is provided by competition between resveratrol synthase and chalcone synthase for a common precursor pool of acyl-CoA derivatives. Polymeric aggregation gives rise, in turn to the viniferins (potent antifungal agents) and procyanidins (strong antioxidants that also inhibit platelet aggregation). The antioxidant effects of red wine and of its major polyphenols have been demonstrated in many experimental systems spanning the range from in vitro studies (human low-density lipoprotein, liposomes, macrophages, cultured cells) to investigations in healthy human subjects. Several of these compounds (notably catechin, quercetin, and resveratrol) promote nitric oxide production by vascular endothelium; inhibit the synthesis of thromboxane in platelets and leukotriene in neutrophils, modulate the synthesis and secretion of lipoproteins in whole animals and human cell lines, and arrest tumour growth as well as inhibit carcinogenesis in different experimental models. Target mechanisms to account for these effects include inhibition of phospholipase A2 and cyclo-oxygenase, inhibition of phosphodiesterase with increase in cyclic nucleotide concentrations, and inhibition of several protein kinases involved in cell signalling. Although their bioavailability remains to be fully established, red wine provides a more favourable milieu than fruits and vegetables, their other dietary source in humans.
Zhu, Xiuping; Kim, Taeyoung; Rahimi, Mohammad; Gorski, Christopher A; Logan, Bruce E
2017-02-22
Salinity gradient energy can be directly converted into electrical power by using reverse electrodialysis (RED) and other technologies, but reported power densities have been too low for practical applications. Herein, the RED stack performance was improved by using 2,6-dihydroxyanthraquinone and ferrocyanide as redox couples. These electrolytes were then used in a flow battery to produce an integrated RED stack and flow battery (RED-FB) system capable of capturing, storing, and discharging salinity gradient energy. Energy captured from the RED stack was discharged in the flow battery at a maximum power density of 3.0 kW m -2 -anode, which was similar to the flow batteries charged by electrical power and could be used for practical applications. Salinity gradient energy captured from the RED stack was recovered from the electrolytes as electricity with 30 % efficiency, and the maximum energy density of the system was 2.4 kWh m -3 -anolyte. The combined RED-FB system overcomes many limitations of previous approaches to capture, store, and use salinity gradient energy from natural or engineered sources. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
Lokar, Marusa; Urbanija, Jasna; Frank, Mojca; Hägerstrand, Henry; Rozman, Blaz; Bobrowska-Hägerstrand, Malgorzata; Iglic, Ales; Kralj-Iglic, Veronika
2008-08-01
Plasma protein-mediated attractive interaction between membranes of red blood cells (RBCs) and phospholipid vesicles was studied. It is shown that beta(2)-glycoprotein I (beta(2)-GPI) may induce RBC discocyte-echinocyte-spherocyte shape transformation and subsequent agglutination of RBCs. Based on the observed beta(2)-GPI-induced RBC cell shape transformation it is proposed that the hydrophobic portion of beta(2)-GPI molecule protrudes into the outer lipid layer of the RBC membrane and increases the area of this layer. It is also suggested that the observed agglutination of RBCs is at least partially driven by an attractive force which is of electrostatic origin and depends on the specific molecular shape and internal charge distribution of membrane-bound beta(2)-GPI molecules. The suggested beta(2)-GPI-induced attractive electrostatic interaction between like-charged RBC membrane surfaces is qualitatively explained by using a simple mathematical model within the functional density theory of the electric double layer, where the electrostatic attraction between the positively charged part of the first domains of bound beta(2)-GPI molecules and negatively charged glycocalyx of the adjacent RBC membrane is taken into account.
[Studies on red orpiment induction of NB4 and HL-60 cell apoptosis].
Bai, Y; Huang, S
1998-09-01
To study the possible mechanism of red orpiment, which is main component of composite indigo naturalis tablets, in the treatment of acute promyelocytic leukemia(APL). The effect of red orpiment on induction of APL cell line NB4 and HL-60 apoptosis were studied by cell morphology, DNA gel electrophoresis and flow cytometry assay. Red orpiment induced NB4 and HL-60 cell apoptosis. When treated with different concentration of red orpiment(25-200 micrograms/ml) for 16 hours, both NB4 and HL-60 cells showed typical apoptosis features. If decreased the concentration of red orpiment to 12.5 micrograms/ml, the NB4 cell still showed apoptosis features while the HL-60 cell did not when cultured for 72 hours. Arsenic disulfide(As2S2) had the same effect as red orpiment did under the same experiment condition. It is the main component, As2S2 of the red orpiment that can induces NB4 and HL-60 cell apoptosis. and the red orpiment is responsible for the high CR rate of APL induced by the composite indigo naturalis tablets.
Red blood cell vesiculation in hereditary hemolytic anemia
Alaarg, Amr; Schiffelers, Raymond M.; van Solinge, Wouter W.; van Wijk, Richard
2013-01-01
Hereditary hemolytic anemia encompasses a heterogeneous group of anemias characterized by decreased red blood cell survival because of inherited membrane, enzyme, or hemoglobin disorders. Affected red blood cells are more fragile, less deformable, and more susceptible to shear stress and oxidative damage, and show increased vesiculation. Red blood cells, as essentially all cells, constitutively release phospholipid extracellular vesicles in vivo and in vitro in a process known as vesiculation. These extracellular vesicles comprise a heterogeneous group of vesicles of different sizes and intracellular origins. They are described in literature as exosomes if they originate from multi-vesicular bodies, or as microvesicles when formed by a one-step budding process directly from the plasma membrane. Extracellular vesicles contain a multitude of bioactive molecules that are implicated in intercellular communication and in different biological and pathophysiological processes. Mature red blood cells release in principle only microvesicles. In hereditary hemolytic anemias, the underlying molecular defect affects and determines red blood cell vesiculation, resulting in shedding microvesicles of different compositions and concentrations. Despite extensive research into red blood cell biochemistry and physiology, little is known about red cell deformability and vesiculation in hereditary hemolytic anemias, and the associated pathophysiological role is incompletely assessed. In this review, we discuss recent progress in understanding extracellular vesicles biology, with focus on red blood cell vesiculation. Also, we review recent scientific findings on the molecular defects of hereditary hemolytic anemias, and their correlation with red blood cell deformability and vesiculation. Integrating bio-analytical findings on abnormalities of red blood cells and their microvesicles will be critical for a better understanding of the pathophysiology of hereditary hemolytic anemias. PMID:24379786
De Franceschi, Lucia; Franco, Robert S.; Bertoldi, Mariarita; Brugnara, Carlo; Matté, Alessandro; Siciliano, Angela; Wieschhaus, Adam J.; Chishti, Athar H.; Joiner, Clinton H.
2013-01-01
Sickle cell disease (SCD) is a globally distributed hereditary red blood cell (RBC) disorder. One of the hallmarks of SCD is the presence of circulating dense RBCs, which are important in SCD-related clinical manifestations. In human dense sickle cells, we found reduced calpastatin activity and protein expression compared to either healthy RBCs or unfractionated sickle cells, suggesting an imbalance between activator and inhibitor of calpain-1 in favor of activator in dense sickle cells. Calpain-1 is a nonlysosomal cysteine proteinase that modulates multiple cell functions through the selective cleavage of proteins. To investigate the relevance of this observation in vivo, we evaluated the effects of the orally active inhibitor of calpain-1, BDA-410 (30 mg/kg/d), on RBCs from SAD mice, a mouse model for SCD. In SAD mice, BDA-410 improved RBC morphology, reduced RBC density (D20; from 1106±0.001 to 1100±0.001 g/ml; P<0.05) and increased RBC-K+ content (from 364±10 to 429±12.3 mmol/kg Hb; P<0.05), markedly reduced the activity of the Ca2+-activated K+channel (Gardos channel), and decreased membrane association of peroxiredoxin-2. The inhibitory effect of calphostin C, a specific inhibitor of protein kinase C (PKC), on the Gardos channel was eliminated after BDA-410 treatment, which suggests that calpain-1 inhibition affects the PKC-dependent fraction of the Gardos channel. BDA-410 prevented hypoxia-induced RBC dehydration and K+ loss in SAD mice. These data suggest a potential role of BDA-410 as a novel therapeutic agent for treatment of SCD.—De Franceschi, L., Franco, R. S., Bertoldi, M., Brugnara, C., Matté, A., Siciliano, A., Wieschhaus, A. J., Chishti, A. H., Joiner, C. H. Pharmacological inhibition of calpain-1 prevents red cell dehydration and reduces Gardos channel activity in a mouse model of sickle cell disease. PMID:23085996
The red-sequence of 72 WINGS local galaxy clusters
NASA Astrophysics Data System (ADS)
Valentinuzzi, T.; Poggianti, B. M.; Fasano, G.; D'Onofrio, M.; Moretti, A.; Ramella, M.; Biviano, A.; Fritz, J.; Varela, J.; Bettoni, D.; Vulcani, B.; Moles, M.; Couch, W. J.; Dressler, A.; Kjærgaard, P.; Omizzolo, A.; Cava, A.
2011-12-01
We study the color - magnitude red sequence and blue fraction of 72 X-ray selected galaxy clusters at z = 0.04-0.07 from the WINGS survey, searching for correlations between the characteristics of the red sequence (RS) and the environment. We consider the slope and scatter of the red sequence, the number ratio of red luminous-to-faint galaxies, the blue fraction, and the fractions of ellipticals, S0s, and spirals that compose the RS. None of these quantities correlate with the cluster velocity dispersion, X-ray luminosity, number of cluster substructures, BCG prevalence over next brightest galaxies, and the spatial concentration of ellipticals. The properties of the RS, instead, depend strongly on local galaxy density. Higher density regions have a smaller RS scatter, a higher luminous-to-faint ratio, a lower blue fraction, and a lower spiral fraction on the RS. Our results clearly illustrate the prominent effect of the local density in setting the epoch when galaxies become passive and join the red sequence, as opposed to the mass of the galaxy host structure.
Inflight Assay of Red Blood Cell Deformability
NASA Technical Reports Server (NTRS)
Ingram, M.; Paglia, D. E.; Eckstein, E. C.; Frazer, R. E.
1985-01-01
Studies on Soviet and American astronauts have demonstrated that red blood cell production is altered in response to low gravity (g) environment. This is associated with changes in individual red cells including increased mean cell volume and altered membrane deformability. During long orbital missions, there is a tendency for the red cell mass deficit to be at least partly corrected although the cell shape anomalies are not. Data currently available suggest that the observed decrease in red cell mass is the result of sudden suppression of erythropoieses and that the recovery trend observed during long missions reflects re-establishment of erythropoietic homeostasis at a "set point" for the red cell mass that is slightly below the normal level at 1 g.
Wang, Jinhui; He, Hua; Xu, Xin; Wang, Xiao; Chen, Yongbing; Yin, Lichen
2018-07-01
Effective anti-cancer therapy is hurdled by the complicated extracellular and intracellular barriers, and thus a smart gene vector that can enable programmable gene delivery is highly demanded. Photo-manipulation of gene delivery processes features spatial and temporal precision, while majority of current strategies utilizes short-wavelength UV/visible light with poor tissue penetration or high-power-density near-infrared (NIR) light that would cause undesired heat damage. Herein, an ROS-degradable polycation was designed and co-delivered with a photosensitizer (PS), thus realizing photo-programmable gene delivery using far-red light (661 nm) at low optical power density (down to 5 mW cm -2 ). Thioketal-crosslinked polyethylenimine (TK-PEI) was synthesized to condense p53 gene to form nanocomplexes (NCs), and hyaluronic acid (HA) modified with pheophytin a (Pha) was coated onto NCs to enhance their colloidal stability and enable cancer cell targeting. Short-time (8-min) light irradiation produced non-lethal amount of ROS to disrupt the endosomal membranes and facilitate p53 gene release via degradation of TK-PEI, which collectively enhanced p53 expression levels toward anti-cancer gene therapy. Long-time (30-min) light irradiation at the post-transfection state generated lethal amount of ROS, which cooperatively killed cancer cells to strengthen p53 gene therapy. To the best of our knowledge, this study represents the first example of an "one stone, three birds" approach to realize cooperative anti-cancer gene therapy using low-power-density, long-wavelength visible light as a single stimulus. Copyright © 2018 Elsevier Ltd. All rights reserved.
Differentiating defects in red oak lumber by discriminant analysis using color, shape, and density
B. H. Bond; D. Earl Kline; Philip A. Araman
2002-01-01
Defect color, shape, and density measures aid in the differentiation of knots, bark pockets, stain/mineral streak, and clearwood in red oak, (Quercus rubra). Various color, shape, and density measures were extracted for defects present in color and X-ray images captured using a color line scan camera and an X-ray line scan detector. Analysis of variance was used to...
[Automatic pre-transfusion serology].
Wattar, B; Govaerts, A
1975-12-01
This paper describes an automated apparatus combining Rosenfield's and Lalezari's antibody screening and identification basic technics. PVP bromelin and low ionic strength acid polybren channels are used; agglutinates are decanded; the remaining cells are hemolyzed and the optical density is then measured through a colorimeter and recorded on a chart; speed is of 40 samples an hour. This machine was also used for irregular antibody screening and identification. Sensitivity is shown to be equal to that of manual technics for ABO, Lewis, Lutheran as well as K, S, M, Kpb, Xga, U and Vel antibodies detection. Nevertheless, a much greater sensitivity is achieved (titers 3 to 10 times higher) than by manual technics for Rh, -k, S, Fya antibodies detection. Polybren channel is suitable for anti-Rh, Duffy, I and M (human detection; bromelin channel however, has a greater sensitivity for other specificities. Anti-M and anti-N sera from rabbits were shown to be non specific when using this machine. Over almost 15 000 sera tested, no antibody (detected by manual techniques) escaped the automated screening. This antibody detection machine was applied to compatibility tests prior to transfusion. (21 480 units were tested. aimed to be transfused to 5 611 patients). A third, PVP without bromelin, was set in parallel in order not to let escape any anti-M, even a weak one. The sera distributor was slaved to the cells distributor so that the whole procedure was automated. Furthermore, each serum was tested against red cells to be transfused, but also against the patient's own red cells to be transfused, but also against the patient's own red cells and against two selected red cells panels, so as to ensure irregular antibody detection at the same time. Using this machine, 3 to 4% of the cell samples were rejected, i.e. more than with usual techniques. All manually detected antibodies were identified, but also some others, which showed only weak reactions by classical techniques. Total results can be obtained within 20 to 30 minutes, which is quite rapid, compared to techniques using for example antiglobulin tests.
Effect of reconstructive vascular surgery on red cell deformability--preliminary results.
Irwin, S T; Rocks, M J; McGuigan, J A; Patterson, C C; Morris, T C; O'Reilly, M J
1983-01-01
Using a simple filtration method, red cell deformability was measured in healthy control subjects and in patients with peripheral vascular disease. Impaired red cell deformability was demonstrated in patients with rest pain or gangrene and in patients with intermittent claudication. An improvement in red cell deformability was demonstrated after successful reconstructive vascular surgery in both patient groups. An improvement in red cell deformability was demonstrated in patients undergoing major limb amputation. PMID:6619311
DOE Office of Scientific and Technical Information (OSTI.GOV)
Garabedian, James E.; Moorman, Christopher E.; Peterson, M. Nils
Understanding how the interplay between social behaviors and habitat structure influences space use is important for conservation of birds in restored habitat. We integrated fine-grained LiDAR-derived habitat data, spatial distribution of cavity trees, and spatially explicit behavioral observations in a multi-scale model to determine the relative importance of conspecific density, intraspecific interactions, and the distribution of cavities on space use by Red-cockaded Woodpeckers (Picoides borealis) on 2 sites in South Carolina, USA. We evaluated candidate models using information theoretic methods. Top scale-specific models included effects of conspecific density and number of cavity tree starts within 200 m of Red-cockaded Woodpeckermore » foraging locations, and effects of the number of intraspecific interactions within 400 m of Red-cockaded Woodpecker foraging locations. The top multi-scale model for 22 of 34 Red-cockaded Woodpecker groups included covariates for the number of groups within 200 m of foraging locations and LiDARderived habitat with moderate densities of large pines (Pinus spp.) and minimal hardwood overstory. These results indicate distribution of neighboring groups was the most important predictor of space use once a minimal set of structural habitat thresholds was reached, and that placing recruitment clusters as little as 400 m from foraging partitions of neighboring groups may promote establishment of new breeding groups in unoccupied habitat. The presence of neighboring groups likely provides cues to foraging Red-cockaded Woodpeckers that facilitate prospecting prior to juvenile dispersal and, to a lesser extent, indicates high-quality forage resources. Careful consideration of local distribution of neighboring groups in potential habitat may improve managers’ ability to increase Red-cockaded Woodpecker density on restored landscapes and mitigate isolation of Red-cockaded Woodpecker groups, a problem that negatively affects fitness across the species’ range.« less
Tripette, Julien; Alexy, Tamas; Hardy-Dessources, Marie-Dominique; Mougenel, Daniele; Beltan, Eric; Chalabi, Tawfik; Chout, Roger; Etienne-Julan, Maryse; Hue, Olivier; Meiselman, Herbert J; Connes, Philippe
2009-08-01
Recent evidence suggests that red blood cell aggregation and the ratio of hematocrit to blood viscosity (HVR), an index of the oxygen transport potential of blood, might considerably modulate blood flow dynamics in the microcirculation. It thus seems likely that these factors could play a role in sickle cell disease. We compared red blood cell aggregation characteristics, blood viscosity and HVR at different shear rates between sickle cell anemia and sickle cell hemoglobin C disease (SCC) patients, sickle cell trait carriers (AS) and control individuals (AA). Blood viscosity determined at high shear rate was lower in sickle cell anemia (n=21) than in AA (n=52), AS (n=33) or SCC (n=21), and was markedly increased in both SCC and AS. Despite differences in blood viscosity, both sickle cell anemia and SCC had similar low HVR values compared to both AA and AS. Sickle cell anemia (n=21) and SCC (n=19) subjects had a lower red blood cell aggregation index and longer time for red blood cell aggregates formation than AA (n=16) and AS (n=15), and a 2 to 3 fold greater shear rate required to disperse red blood cell aggregates. The low HVR levels found in sickle cell anemia and SCC indicates a comparable low oxygen transport potential of blood in both genotypes. Red blood cell aggregation properties are likely to be involved in the pathophysiology of sickle cell disease: the increased shear forces needed to disperse red blood cell aggregates may disturb blood flow, especially at the microcirculatory level, since red blood cell are only able to pass through narrow capillaries as single cells rather than as aggregates.
Blood volume and red cell life span (M113), part C
NASA Technical Reports Server (NTRS)
Johnson, P. C., Jr.
1973-01-01
Prechamber, in-chamber, and postchamber blood samples taken from Skylab simulation crewmembers did not indicate significant shortening of the red cell life span during the mission. This does not suggest that the space simulation environment could not be associated with red cell enzyme changes. It does show that any changes in enzymes were not sufficiently great to significantly shorten red cell survival. There was no evidence of bone marrow erythropoetic suppression nor was there any evidence of increased red cell destruction.
Paul Tooley; Marsha Browning; Robert Leighty
2013-01-01
Our objectives were to establish inoculum density relationships between P. ramorum and selected hosts using detached leaf and whole-plant inoculations. Young plants and detached leaves of Quercus prinus (Chestnut oak), Q. rubra (Northern red oak), Acer rubrum (red maple), ...
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.
Observations of circumstellar carbon monoxide and evidence for multiple ejections in red giants
NASA Technical Reports Server (NTRS)
Bernat, A. P.
1981-01-01
Observations of the fundamental 4.6 micron band of CO in nine red giants are presented. A common feature is multiple absorption lines which are identified as products of separate components or shells. Column densities are derived; the relative values should be free of the uncertainties inherent in determining the absolute scale. These column densities are well fitted by single excitation temperatures for each absorption component; these excitation temperatures are identified with the local kinetic temperatures. There is no correlation of CO column density with either gas or dust column density nor of the expansion velocity of the component with its distance from the star. The evidence is reviewed, and it is concluded that mass loss from red giants is most likely episodic in nature.
21 CFR 660.30 - Reagent Red Blood Cells.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 21 Food and Drugs 7 2010-04-01 2010-04-01 false Reagent Red Blood Cells. 660.30 Section 660.30...) BIOLOGICS ADDITIONAL STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Reagent Red Blood Cells § 660.30 Reagent Red Blood Cells. (a) Proper name and definition. The proper name of the product shall be...
21 CFR 660.30 - Reagent Red Blood Cells.
Code of Federal Regulations, 2013 CFR
2013-04-01
... 21 Food and Drugs 7 2013-04-01 2013-04-01 false Reagent Red Blood Cells. 660.30 Section 660.30...) BIOLOGICS ADDITIONAL STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Reagent Red Blood Cells § 660.30 Reagent Red Blood Cells. (a) Proper name and definition. The proper name of the product shall be...
21 CFR 660.30 - Reagent Red Blood Cells.
Code of Federal Regulations, 2014 CFR
2014-04-01
... 21 Food and Drugs 7 2014-04-01 2014-04-01 false Reagent Red Blood Cells. 660.30 Section 660.30...) BIOLOGICS ADDITIONAL STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Reagent Red Blood Cells § 660.30 Reagent Red Blood Cells. (a) Proper name and definition. The proper name of the product shall be...
21 CFR 660.30 - Reagent Red Blood Cells.
Code of Federal Regulations, 2012 CFR
2012-04-01
... 21 Food and Drugs 7 2012-04-01 2012-04-01 false Reagent Red Blood Cells. 660.30 Section 660.30...) BIOLOGICS ADDITIONAL STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Reagent Red Blood Cells § 660.30 Reagent Red Blood Cells. (a) Proper name and definition. The proper name of the product shall be...
Rodrigo, Rexan; Allen, Angela; Manampreri, Aresha; Perera, Luxman; Fisher, Christopher A; Allen, Stephen; Weatherall, David J; Premawardhena, Anuja
2018-07-01
Iron deficiency complicates the use of red cell indices to screen for carriers of haemoglobin variants in many populations. In a cross sectional survey of 7526 secondary school students from 25 districts of Sri Lanka, 1963 (26.0%) students had low red cell indices. Iron deficiency, identified by low serum ferritin, was the major identifiable cause occurring in 550/1806 (30.5%) students. Low red cell indices occurred in iron-replete students with alpha-thalassaemia including those with single alpha-globin gene deletions. Anaemia and low red cell indices were also common in beta-thalassaemia trait. An unexpected finding was that low red cell indices occurred in 713 iron-replete students with a normal haemoglobin genotype. It is common practice to prescribe iron supplements to individuals with low red cell indices. Since low red cell indices were a feature of all forms of α thalassaemia and also of iron deficiency, in areas where both conditions are common, such as Sri Lanka, it is imperative to differentiate between the two, to allow targeted administration of iron supplements and avoid the possible deleterious effects of increased iron availability in iron replete individuals with low red cell indices due to other causes such as α thalassaemia. Copyright © 2018 Elsevier Inc. All rights reserved.
Red Dot Basal Cell Carcinoma: An Unusual Variant of a Common Malignancy.
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.
Reduced DIDS-sensitive chloride conductance in Ae1-/- mouse erythrocytes
Alper, Seth L.; Vandorpe, David H.; Peters, Luanne L.; Brugnara, Carlo
2008-01-01
The resting membrane potential of the human erythrocyte is largely determined by a constitutive Cl- conductance ∼100-fold greater than the resting cation conductance. The 4,4′-diisothiocyanostilbene-2,2′-disulfonic acid (DIDS)-sensitive electroneutral Cl- transport mediated by the human erythroid Cl-/HCO3- exchanger, AE1 (SLC4A1, band 3) is ≥10,000-fold greater than can be accounted for by the Cl- conductance of the red cell. The molecular identities of conductive anion pathways across the red cell membrane remain poorly defined. We have examined red cell Cl- conductance in the Ae1-/- mouse as a genetic test of the hypothesis that Ae1 mediates DIDS-sensitive Cl- conductance in mouse red cells. We report here that wildtype mouse red cell membrane potential resembles that of human red cells in the predominance of its Cl- conductance. We show with four technical approaches that the DIDS-sensitive component of erythroid Cl- conductance is reduced or absent from Ae1-/- red cells. These results are consistent with the hypothesis that the Ae1 anion exchanger polypeptide can operate infrequently in a conductive mode. However, the fragile red cell membrane of the Ae1-/- mouse red cell exhibits reduced abundance or loss of multiple polypeptides. Thus, loss of one or more distinct, DIDS-sensitive anion channel polypeptide(s) from the Ae1-/- red cell membrane cannot be ruled out as an explanation for the reduced DIDS-sensitive anion conductance. PMID:18329299
Olivier, Emmanuel; Qiu, Caihong; Bouhassira, Eric E
2012-08-01
The current supply of red blood cells expressing rare blood groups is not sufficient to cover all the existing transfusion needs for chronically transfused patients, such as sickle cell disease homozygous carriers, because of alloimmunization. In vitro production of cultured red blood cells is slowly emerging as a possible complement to the existing collection-based red blood cell procurement system. The yield of cultured red blood cells can theoretically be maximized by amplifying the stem, progenitor, or precursor compartment. Here, we combined methods designed to expand these three compartments to optimize the yield of cultured red blood cells and found that exposing CD34(+) cells to a short pulse of cytokines favorable for erythroid differentiation prior to stem cell expansion followed by progenitor expansion produced the highest yield of erythroid cells. This novel serum-free red blood cell production protocol was efficient on CD34(+) cells derived from human embryonic stem cells, 6-8-week yolk sacs, 16-18-week fetal livers, cord blood, and peripheral blood. The yields of cells obtained with these new protocols were larger by an order of magnitude than the yields observed previously. Globin expression analysis by high-performance liquid chromatography revealed that these expansion protocols generally yielded red blood cells that expressed a globin profile similar to that expected for the developmental age of the CD34(+) cells.
Nemkov, Travis; Sun, Kaiqi; Reisz, Julie A; Song, Anren; Yoshida, Tatsuro; Dunham, Andrew; Wither, Matthew J; Francis, Richard O; Roach, Robert C; Dzieciatkowska, Monika; Rogers, Stephen C; Doctor, Allan; Kriebardis, Anastasios; Antonelou, Marianna; Papassideri, Issidora; Young, Carolyn T; Thomas, Tiffany A; Hansen, Kirk C; Spitalnik, Steven L; Xia, Yang; Zimring, James C; Hod, Eldad A; D'Alessandro, Angelo
2018-02-01
Hypoxanthine catabolism in vivo is potentially dangerous as it fuels production of urate and, most importantly, hydrogen peroxide. However, it is unclear whether accumulation of intracellular and supernatant hypoxanthine in stored red blood cell units is clinically relevant for transfused recipients. Leukoreduced red blood cells from glucose-6-phosphate dehydrogenase-normal or -deficient human volunteers were stored in AS-3 under normoxic, hyperoxic, or hypoxic conditions (with oxygen saturation ranging from <3% to >95%). Red blood cells from healthy human volunteers were also collected at sea level or after 1-7 days at high altitude (>5000 m). Finally, C57BL/6J mouse red blood cells were incubated in vitro with 13 C 1 -aspartate or 13 C 5 -adenosine under normoxic or hypoxic conditions, with or without deoxycoformycin, a purine deaminase inhibitor. Metabolomics analyses were performed on human and mouse red blood cells stored for up to 42 or 14 days, respectively, and correlated with 24 h post-transfusion red blood cell recovery. Hypoxanthine increased in stored red blood cell units as a function of oxygen levels. Stored red blood cells from human glucose-6-phosphate dehydrogenase-deficient donors had higher levels of deaminated purines. Hypoxia in vitro and in vivo decreased purine oxidation and enhanced purine salvage reactions in human and mouse red blood cells, which was partly explained by decreased adenosine monophosphate deaminase activity. In addition, hypoxanthine levels negatively correlated with post-transfusion red blood cell recovery in mice and - preliminarily albeit significantly - in humans. In conclusion, hypoxanthine is an in vitro metabolic marker of the red blood cell storage lesion that negatively correlates with post-transfusion recovery in vivo Storage-dependent hypoxanthine accumulation is ameliorated by hypoxia-induced decreases in purine deamination reaction rates. Copyright© 2018 Ferrata Storti Foundation.
Nemkov, Travis; Sun, Kaiqi; Reisz, Julie A.; Song, Anren; Yoshida, Tatsuro; Dunham, Andrew; Wither, Matthew J.; Francis, Richard O.; Roach, Robert C.; Dzieciatkowska, Monika; Rogers, Stephen C.; Doctor, Allan; Kriebardis, Anastasios; Antonelou, Marianna; Papassideri, Issidora; Young, Carolyn T.; Thomas, Tiffany A.; Hansen, Kirk C.; Spitalnik, Steven L.; Xia, Yang; Zimring, James C.; Hod, Eldad A.; D’Alessandro, Angelo
2018-01-01
Hypoxanthine catabolism in vivo is potentially dangerous as it fuels production of urate and, most importantly, hydrogen peroxide. However, it is unclear whether accumulation of intracellular and supernatant hypoxanthine in stored red blood cell units is clinically relevant for transfused recipients. Leukoreduced red blood cells from glucose-6-phosphate dehydrogenase-normal or -deficient human volunteers were stored in AS-3 under normoxic, hyperoxic, or hypoxic conditions (with oxygen saturation ranging from <3% to >95%). Red blood cells from healthy human volunteers were also collected at sea level or after 1–7 days at high altitude (>5000 m). Finally, C57BL/6J mouse red blood cells were incubated in vitro with 13C1-aspartate or 13C5-adenosine under normoxic or hypoxic conditions, with or without deoxycoformycin, a purine deaminase inhibitor. Metabolomics analyses were performed on human and mouse red blood cells stored for up to 42 or 14 days, respectively, and correlated with 24 h post-transfusion red blood cell recovery. Hypoxanthine increased in stored red blood cell units as a function of oxygen levels. Stored red blood cells from human glucose-6-phosphate dehydrogenase-deficient donors had higher levels of deaminated purines. Hypoxia in vitro and in vivo decreased purine oxidation and enhanced purine salvage reactions in human and mouse red blood cells, which was partly explained by decreased adenosine monophosphate deaminase activity. In addition, hypoxanthine levels negatively correlated with post-transfusion red blood cell recovery in mice and – preliminarily albeit significantly - in humans. In conclusion, hypoxanthine is an in vitro metabolic marker of the red blood cell storage lesion that negatively correlates with post-transfusion recovery in vivo. Storage-dependent hypoxanthine accumulation is ameliorated by hypoxia-induced decreases in purine deamination reaction rates. PMID:29079593
Bonum vinum laetificat cor hominum.
Stoclet, J C
2001-01-01
Beneficial effects of wine consumption on health have been suspected since the antiquity. Recent epidemiological studies show that coronary heart disease mortality markedly decreases from northern to southern Europe and is lower in Mediterranean than in other developed countries. Because wine is a component of the Mediterranean diet, it has been suggested that moderate wine especially red wine consumption may produce additional beneficial effects on cardiovascular morbidity and mortality compared to consuming the same quantity of alcohol in other beverages. Polyphenols are good candidates to explain the putative cardiovascular protective effect of wine, because they are abundant in wine especially red wine, and possess antioxidant and superoxide ion scavenging properties. Because it is readily accessible from blood and produces cardioprotective agents like nitric oxide (NO) the endothelial cell may be a privileged target for wine polyphenols. Polyphenols from red wine can prevent oxidation of low density lipoproteins (LDL). As oxidized LDL inhibit agonist-activated NO release from endothelial cells and subsequent endothelium-dependent relaxation of arteries, wine polyphenols might prevent LDL-induced alterations of endothelial function. Furthermore some wine polyphenols contained in oligomeric condensed tannins- and anthocyaninsD enriched fractions can act directly on endothelial cells to cause calcium-dependent release of NO. The latter effect is independent from superoxide scavenging and antioxidant properties of the polyphenols, and it is produced by compounds with specific structures only. Thus, decreased oxidation of LDL and enhanced release of NO from endothelium caused by polyphenols from red wine may result in cardiovascular protection. However further studies are required to demonstrate whether or not these effects are involved in the putative protective effect of wine on cardiovascular morbidity and mortality.
Pineda, Jesús; Cho, Walter; Starczak, Victoria; Govindarajan, Annette F; Guzman, Héctor M; Girdhar, Yogesh; Holleman, Rusty C; Churchill, James; Singh, Hanumant; Ralston, David K
2016-01-01
A research cruise to Hannibal Bank, a seamount and an ecological hotspot in the coastal eastern tropical Pacific Ocean off Panama, explored the zonation, biodiversity, and the ecological processes that contribute to the seamount's elevated biomass. Here we describe the spatial structure of a benthic anomuran red crab population, using submarine video and autonomous underwater vehicle (AUV) photographs. High density aggregations and a swarm of red crabs were associated with a dense turbid layer 4-10 m above the bottom. The high density aggregations were constrained to 355-385 m water depth over the Northwest flank of the seamount, although the crabs also occurred at lower densities in shallower waters (∼280 m) and in another location of the seamount. The crab aggregations occurred in hypoxic water, with oxygen levels of 0.04 ml/l. Barcoding of Hannibal red crabs, and pelagic red crabs sampled in a mass stranding event in 2015 at a beach in San Diego, California, USA, revealed that the Panamanian and the Californian crabs are likely the same species, Pleuroncodes planipes, and these findings represent an extension of the southern endrange of this species. Measurements along a 1.6 km transect revealed three high density aggregations, with the highest density up to 78 crabs/m(2), and that the crabs were patchily distributed. Crab density peaked in the middle of the patch, a density structure similar to that of swarming insects.
Cho, Walter; Starczak, Victoria; Govindarajan, Annette F.; Guzman, Héctor M.; Girdhar, Yogesh; Holleman, Rusty C.; Churchill, James; Singh, Hanumant; Ralston, David K.
2016-01-01
A research cruise to Hannibal Bank, a seamount and an ecological hotspot in the coastal eastern tropical Pacific Ocean off Panama, explored the zonation, biodiversity, and the ecological processes that contribute to the seamount’s elevated biomass. Here we describe the spatial structure of a benthic anomuran red crab population, using submarine video and autonomous underwater vehicle (AUV) photographs. High density aggregations and a swarm of red crabs were associated with a dense turbid layer 4–10 m above the bottom. The high density aggregations were constrained to 355–385 m water depth over the Northwest flank of the seamount, although the crabs also occurred at lower densities in shallower waters (∼280 m) and in another location of the seamount. The crab aggregations occurred in hypoxic water, with oxygen levels of 0.04 ml/l. Barcoding of Hannibal red crabs, and pelagic red crabs sampled in a mass stranding event in 2015 at a beach in San Diego, California, USA, revealed that the Panamanian and the Californian crabs are likely the same species, Pleuroncodes planipes, and these findings represent an extension of the southern endrange of this species. Measurements along a 1.6 km transect revealed three high density aggregations, with the highest density up to 78 crabs/m2, and that the crabs were patchily distributed. Crab density peaked in the middle of the patch, a density structure similar to that of swarming insects. PMID:27114859
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 of the preoperative cancer was greater than 12:1, demonstrating a significant lateral spread of the tumor beyond the observed clinical margins of the neoplasm. In conclusion, in a patient with a personal history of actinic keratosis or nonmelanoma skin cancer, the appearance of a new red dot in a sun-exposed site should prompt additional evaluation of the skin lesion to exclude or establish the diagnosis of red dot basal cell carcinoma.
2017-01-01
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 of the preoperative cancer was greater than 12:1, demonstrating a significant lateral spread of the tumor beyond the observed clinical margins of the neoplasm. In conclusion, in a patient with a personal history of actinic keratosis or nonmelanoma skin cancer, the appearance of a new red dot in a sun-exposed site should prompt additional evaluation of the skin lesion to exclude or establish the diagnosis of red dot basal cell carcinoma. PMID:28465868
Faraghat, Shabnam A; Hoettges, Kai F; Steinbach, Max K; van der Veen, Daan R; Brackenbury, William J; Henslee, Erin A; Labeed, Fatima H; Hughes, Michael P
2017-05-02
Currently, cell separation occurs almost exclusively by density gradient methods and by fluorescence- and magnetic-activated cell sorting (FACS/MACS). These variously suffer from lack of specificity, high cell loss, use of labels, and high capital/operating cost. We present a dielectrophoresis (DEP)-based cell-separation method, using 3D electrodes on a low-cost disposable chip; one cell type is allowed to pass through the chip whereas the other is retained and subsequently recovered. The method advances usability and throughput of DEP separation by orders of magnitude in throughput, efficiency, purity, recovery (cells arriving in the correct output fraction), cell losses (those which are unaccounted for at the end of the separation), and cost. The system was evaluated using three example separations: live and dead yeast; human cancer cells/red blood cells; and rodent fibroblasts/red blood cells. A single-pass protocol can enrich cells with cell recovery of up to 91.3% at over 300,000 cells per second with >3% cell loss. A two-pass protocol can process 300,000,000 cells in under 30 min, with cell recovery of up to 96.4% and cell losses below 5%, an effective processing rate >160,000 cells per second. A three-step protocol is shown to be effective for removal of 99.1% of RBCs spiked with 1% cancer cells while maintaining a processing rate of ∼170,000 cells per second. Furthermore, the self-contained and low-cost nature of the separator device means that it has potential application in low-contamination applications such as cell therapies, where good manufacturing practice compatibility is of paramount importance.
Quantification of the fraction poorly deformable red blood cells using ektacytometry.
Streekstra, G J; Dobbe, J G G; Hoekstra, A G
2010-06-21
We describe a method to obtain the fraction of poorly deformable red blood cells in a blood sample from the intensity pattern in an ektacytometer. In an ektacytometer red blood cells are transformed into ellipsoids by a shear flow between two transparent cylinders. The intensity pattern, due to a laser beam that is sent through the suspension, is projected on a screen. When measuring a healthy red blood cell population iso-intensity curves are ellipses with an axial ratio equal to that of the average red blood cell. In contrast poorly deformable cells result in circular iso-intensity curves. In this study we show that for mixtures of deformable and poorly deformable red blood cells, iso-intensity curves in the composite intensity pattern are neither elliptical nor circular but obtain cross-like shapes. We propose a method to obtain the fraction of poorly deformable red blood cells from those intensity patterns. Experiments with mixtures of poorly deformable and deformable red blood cells validate the method and demonstrate its accuracy. In a clinical setting our approach is potentially of great value for the detection of the fraction of sickle cells in blood samples of patients with sickle cell disease or to find a measure for the parasitemia in patients infected with malaria.
Durmus, Naside Gozde; Davis, Ronald W.; Steinmetz, Lars M.; Demirci, Utkan
2016-01-01
There is an emerging need for portable, robust, inexpensive and easy-to-use disease diagnosis and prognosis monitoring platforms to share health information at the point-of-living, including clinical and home settings. Recent advances in digital health technologies have improved early diagnosis, drug treatment, and personalized medicine. Smartphones with high-resolution cameras and high data processing power enable intriguing biomedical applications when integrated with diagnostic devices. Further, these devices have immense potential to contribute to public health in resource-limited settings where there is a particular need for portable, rapid, label-free, easy-to-use and affordable biomedical devices to diagnose and continuously monitor patients for precision medicine, especially those suffering from rare diseases, such as sickle cell anemia, thalassemia and chronic fatigue syndrome. Here, we present a magnetic levitation-based diagnosis system in which different cell types (i.e., white and red blood cells) are levitated in a magnetic gradient and separated due to their unique densities. Moreover, we introduce an easy-to-use, smartphone incorporated levitation system for cell analysis. Using our portable imaging magnetic levitation (i-LEV) system, we show that white and red blood cells can be identified and cell numbers can be quantified without using any labels. In addition, cells levitated in i-LEV can be distinguished at single cell resolution, potentially enabling diagnosis and monitoring, as well as clinical and research applications. PMID:26523938
Baday, Murat; Calamak, Semih; Durmus, Naside Gozde; Davis, Ronald W; Steinmetz, Lars M; Demirci, Utkan
2016-03-02
There is an emerging need for portable, robust, inexpensive, and easy-to-use disease diagnosis and prognosis monitoring platforms to share health information at the point-of-living, including clinical and home settings. Recent advances in digital health technologies have improved early diagnosis, drug treatment, and personalized medicine. Smartphones with high-resolution cameras and high data processing power enable intriguing biomedical applications when integrated with diagnostic devices. Further, these devices have immense potential to contribute to public health in resource-limited settings where there is a particular need for portable, rapid, label-free, easy-to-use, and affordable biomedical devices to diagnose and continuously monitor patients for precision medicine, especially those suffering from rare diseases, such as sickle cell anemia, thalassemia, and chronic fatigue syndrome. Here, a magnetic levitation-based diagnosis system is presented in which different cell types (i.e., white and red blood cells) are levitated in a magnetic gradient and separated due to their unique densities. Moreover, an easy-to-use, smartphone incorporated levitation system for cell analysis is introduced. Using our portable imaging magnetic levitation (i-LEV) system, it is shown that white and red blood cells can be identified and cell numbers can be quantified without using any labels. In addition, cells levitated in i-LEV can be distinguished at single-cell resolution, potentially enabling diagnosis and monitoring, as well as clinical and research applications. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Integration of red cell genotyping into the blood supply chain: a population-based study.
Flegel, Willy A; Gottschall, Jerome L; Denomme, Gregory A
2015-07-01
When problems with compatibility arise, transfusion services often use time-consuming serological tests to identify antigen-negative red cell units for safe transfusion. New methods have made red cell genotyping possible for all clinically relevant blood group antigens. We did mass-scale genotyping of donor blood and provided hospitals with access to a large red cell database to meet the demand for antigen-negative red cell units beyond ABO and Rh blood typing. We established a red cell genotype database at the BloodCenter of Wisconsin on July 17, 2010. All self-declared African American, Asian, Hispanic, and Native American blood donors were eligible irrespective of their ABO and Rh type or history of donation. Additionally, blood donors who were groups O, A, and B, irrespective of their Rh phenotype, were eligible for inclusion only if they had a history of at least three donations in the previous 3 years, with one donation in the previous 12 months at the BloodCenter of Wisconsin. We did red cell genotyping with a nanofluidic microarray system, using 32 single nucleotide polymorphisms to predict 42 blood group antigens. An additional 14 antigens were identified via serological phenotype. We monitored the ability of the red cell genotype database to meet demand for compatible blood during 3 years. In addition to the central database at the BloodCenter of Wisconsin, we gave seven hospitals online access to a web-based antigen query portal on May 1, 2013, to help them to locate antigen-negative red cell units in their own inventories. We analysed genotype data for 43,066 blood donors. Requests were filled for 5661 (99.8%) of 5672 patient encounters in which antigen-negative red cell units were needed. Red cell genotyping met the demand for antigen-negative blood in 5339 (94.1%) of 5672 patient encounters, and the remaining 333 (5.9%) requests were filled by use of serological data. Using the 42 antigens represented in our red cell genotype database, we were able to fill 14,357 (94.8%) of 15,140 requests for antigen-negative red cell units from hospitals served by the BloodCenter of Wisconsin. In the pilot phase, the seven hospitals identified 71 units from 52 antigen-negative red cell unit requests. Red cell genotyping has the potential to transform the way antigen-negative red cell units are provided. An antigen query portal could reduce the need for transportation of blood and serological screening. If this wealth of genotype data can be made easily accessible online, it will help with the supply of affordable antigen-negative red cell units to ensure patient safety. BloodCenter of Wisconsin Diagnostic Laboratories Strategic Initiative and the NIH Clinical Center Intramural Research Program. Copyright © 2015 Elsevier Ltd. All rights reserved.
Sickle red cell-endothelium interactions.
Kaul, Dhananjay K; Finnegan, Eileen; Barabino, Gilda A
2009-01-01
Periodic recurrence of painful vaso-occlusive crisis is the defining feature of sickle cell disease. Among multiple pathologies associated with this disease, sickle red cell-endothelium interaction has been implicated as a potential initiating mechanism in vaso-occlusive events. This review focuses on various interrelated mechanisms involved in human sickle red cell adhesion. We discuss in vitro and microcirculatory findings on sickle red cell adhesion, its potential role in vaso-occlusion, and the current understanding of receptor-ligand interactions involved in this pathological phenomenon. In addition, we discuss the contribution of other cellular interactions (leukocytes recruitment and leukocyte-red cell interaction) to vaso-occlusion, as observed in transgenic sickle mouse models. Emphasis is given to recently discovered adhesion molecules that play a predominant role in mediating human sickle red cell adhesion. Finally, we analyze various therapeutic approaches for inhibiting sickle red cell adhesion by targeting adhesion molecules and also consider therapeutic strategies that target stimuli involved in endothelial activation and initiation of adhesion.
Gevaert, D; Nelis, J; Verhaeghe, B
1991-09-01
Polyuria-polydipsia is a frequent observation in pigeons with salmonellosis. These are accompanied by a decreased albumin/globulin ratio, increased creatinine and haptoglobin concentrations, and decrease in the chloride concentration in the blood plasma. The urine was found to have a low density with red and white blood cells frequently present in the sediment. A water deprivation test was conducted on three animals: polyuria disappeared and plasma urea increased significantly.
High Energy Density Lithium Primary Cells Using Nitrogen Containing Polymer Positives.
1983-12-01
the charges were stabilized on heteroatoms, particularly nitro- gen. A positive charge would be stored in the form of an ammonium ion. in a high...operate reversibly. 2.0 POLYMERIC CATHODES A polymer which might be expected to exemplify charge stabilization by nitrogen is poly-N-methylpyrrole (PMP...This material is electronically conductive and might store one charge per nitrogen atom. ox. PMP;4 N3 red. I N + N+ An additional, seductive attraction
21 CFR 864.7100 - Red blood cell enzyme assay.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Red blood cell enzyme assay. 864.7100 Section 864... enzyme assay. (a) Identification. Red blood cell enzyme assay is a device used to measure the activity in... kinase or 2,3-diphosphoglycerate. A red blood cell enzyme assay is used to determine the enzyme defects...
21 CFR 864.7100 - Red blood cell enzyme assay.
Code of Federal Regulations, 2014 CFR
2014-04-01
... enzyme assay. (a) Identification. Red blood cell enzyme assay is a device used to measure the activity in... kinase or 2,3-diphosphoglycerate. A red blood cell enzyme assay is used to determine the enzyme defects... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Red blood cell enzyme assay. 864.7100 Section 864...
42 CFR 410.161 - Part B blood deductible.
Code of Federal Regulations, 2013 CFR
2013-10-01
... deductible. (a) General rules. (1) As used in this section, packed red cells means the red blood cells that remain after plasma is separated from whole blood. (2) A unit of packed red cells is treated as the... beneficiary is responsible for the first three units of whole blood or packed red cells received during a...
21 CFR 864.7100 - Red blood cell enzyme assay.
Code of Federal Regulations, 2013 CFR
2013-04-01
... enzyme assay. (a) Identification. Red blood cell enzyme assay is a device used to measure the activity in... kinase or 2,3-diphosphoglycerate. A red blood cell enzyme assay is used to determine the enzyme defects... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Red blood cell enzyme assay. 864.7100 Section 864...
42 CFR 410.161 - Part B blood deductible.
Code of Federal Regulations, 2012 CFR
2012-10-01
... deductible. (a) General rules. (1) As used in this section, packed red cells means the red blood cells that remain after plasma is separated from whole blood. (2) A unit of packed red cells is treated as the... beneficiary is responsible for the first three units of whole blood or packed red cells received during a...
42 CFR 410.161 - Part B blood deductible.
Code of Federal Regulations, 2014 CFR
2014-10-01
... deductible. (a) General rules. (1) As used in this section, packed red cells means the red blood cells that remain after plasma is separated from whole blood. (2) A unit of packed red cells is treated as the... beneficiary is responsible for the first three units of whole blood or packed red cells received during a...
42 CFR 410.161 - Part B blood deductible.
Code of Federal Regulations, 2011 CFR
2011-10-01
... deductible. (a) General rules. (1) As used in this section, packed red cells means the red blood cells that remain after plasma is separated from whole blood. (2) A unit of packed red cells is treated as the... beneficiary is responsible for the first three units of whole blood or packed red cells received during a...
21 CFR 864.7100 - Red blood cell enzyme assay.
Code of Federal Regulations, 2012 CFR
2012-04-01
... enzyme assay. (a) Identification. Red blood cell enzyme assay is a device used to measure the activity in... kinase or 2,3-diphosphoglycerate. A red blood cell enzyme assay is used to determine the enzyme defects... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Red blood cell enzyme assay. 864.7100 Section 864...
21 CFR 864.7100 - Red blood cell enzyme assay.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Red blood cell enzyme assay. 864.7100 Section 864...) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Kits and Packages § 864.7100 Red blood cell enzyme assay. (a) Identification. Red blood cell enzyme assay is a device used to measure the activity in...
Red blood cell sedimentation of Apheresis Granulocytes.
Lodermeier, Michelle A; Byrne, Karen M; Flegel, Willy A
2017-10-01
Sedimentation of Apheresis Granulocyte components removes red blood cells. It is used to increase the blood donor pool when blood group-compatible donors cannot be recruited for a patient because of a major ABO incompatibility or incompatible red blood cell antibodies in the recipient. Because granulocytes have little ABO and few other red blood cell antigens on their membrane, such incompatibility lies mostly with the contaminating red blood cells. Video Clip S1 shows the process of red blood cell sedimentation of an Apheresis Granulocyte component. This video was filmed with a single smart phone attached to a commercial tripod and was edited on a tablet computer with free software by an amateur videographer without prior video experience. © 2017 AABB.
Effect of electron withdrawing unit for dye-sensitized solar cell based on D-A-π-A organic dyes
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kwon, Dong Yuel; Chang, Dong Min; Kim, Young Sik, E-mail: youngkim@hongik.ac.kr
2014-10-15
Highlights: • To gain the red-shifted absorption spectra, withdrawing unit was substituted in dye. • By the introduction of additional withdrawing unit, LUMOs level of dye are decreased. • Decreasing LUMOs level of dye caused the red-shifted absorption spectra of dye. • Novel acceptor, DCRD, showed better photovoltaic properties than cyanoacetic acid. - Abstract: In this work, two novel D-A-π-A dye sensitizers with triarylamine as an electron donor, isoindigo and cyano group as electron withdrawing units and cyanoacetic acid and 2-(1,1-dicyanomethylene) rhodanine as an electron acceptor for an anchoring group (TICC, TICR) were designed and investigated with the ID6 dyemore » as the reference. The difference in HOMO and LUMO levels were compared according to the presence or absence of isoindigo in ID6 (TC and ID6). To gain insight into the factors responsible for photovoltaic performance, we used density functional theory (DFT) and time-dependent density functional theory (TDDFT) calculations. Owing to different LUMO levels for each acceptor, the absorption band and molar extinction coefficient of each dye was different. Among the dyes, TICR showed more red-shifted and broader absorption spectra than other dyes and had a higher molar extinction coefficient than the reference. It is expected that TICR would show better photovoltaic properties than the other dyes, including the reference dye.« less
Liu, Yanju; Naidu, Ravendra; Ming, Hui
2013-03-15
The surface electrochemical properties of red mud (bauxite residue) from different alumina refineries in Australia and China were studied by electrophoresis and measuring surface charge density obtained from acid/base potentiometric titrations. The electrophoretic properties were measured from zeta potentials obtained in the presence of 0.01 and 0.001 M KNO(3) over a wide pH range (3.5-10) by titration. The isoelectric point (IEP) values were found to vary from 6.35 to 8.70 for the red mud samples. Further investigation into the surface charge density of one sample (RRM) by acid/base potentiometric titration showed similar results for pH(PZC) with pH(IEP) obtained from electrokinetic measurements. The pH(IEP) determined from zeta potential measurements can be used as a characteristic property of red mud. The minerals contained in red mud contributed to the different values of pH(IEP) of samples obtained from different refineries. Different relationships of pH(IEP) with Al/Fe and Al/Si ratios (molar basis) were also found for different red mud samples. Copyright © 2012 Elsevier Inc. All rights reserved.
Combinational light emitting diode-high frequency focused ultrasound treatment for HeLa cell.
Choe, Se-Woon; Park, Kitae; Park, Chulwoo; Ryu, Jaemyung; Choi, Hojong
2017-12-01
Light sources such as laser and light emitting diode or ultrasound devices have been widely used for cancer therapy and regenerative medicines, since they are more cost-effective and less harmful than radiation therapy, chemotherapy or magnetic treatment. Compared to laser and low intensity ultrasound techniques, light emitting diode and high frequency focused ultrasound shows enhanced therapeutic effects, especially for small tumors. We propose combinational light emitting diode-high frequency focused ultrasound treatment for human cervical cancer HeLa cells. Individual red, green, and blue light emitting diode light only, high frequency focused ultrasound only, or light emitting diode light combined with high frequency focused ultrasound treatments were applied in order to characterize the responses of HeLa cells. Cell density exposed by blue light emitting diode light combined with high frequency focused ultrasound (2.19 ± 0.58%) was much lower than that of cells exposed by red and green light emitting diode lights (81.71 ± 9.92% and 61.81 ± 4.09%), blue light emitting diode light (11.19 ± 2.51%) or high frequency focused ultrasound only (9.72 ± 1.04%). We believe that the proposed combinational blue light emitting diode-high frequency focused ultrasound treatment could have therapeutic benefits to alleviate cancer cell proliferation.
MedlinePlus Videos and Cool Tools
... body's tissues in exchange for carbon dioxide, which is carried to and eliminated by the lungs. Red blood cells are formed in the red bone marrow ... 2 days. The body makes about two million red blood cells every second. Blood is made up of both cellular and liquid components. ...
Development of enhancing agglutination reaction using gold nanoparticle for pre-transfusion testing.
Choktaweesak, N; Krasathong, P; Ammaranond, P
2016-10-01
To explore an alternative way for antibody detection testing, the examination of gold nanoparticle solution for enhancing unexpected antibodies for pre-transfusion testing was investigated. Exposure of foreign antigens on red blood cells from transfusion can trigger the immune system to produce unexpected antibodies. This immunological response may cause the complication to future transfusion. For detection of unexpected antibodies, the antibody screening test is performed approximately 30-60 min. To reduce turnaround time, enhancing reagent, low-ionic strength solution (LISS), is widely used. However, cost of enhancing reagent is an issue which has concerned in resource limited countries. Gold nanoparticle solution can increase red blood cells agglutination reaction. To solve this issue, study of gold nanoparticle solution was investigated. Samples were performed comparing between LISS and gold nanoparticle solution at antiglobulin phase. After reading the agglutination reaction, supernatants were collected and measured at the optical density at 760 nm by spectrophotometer. The optical density in the tube of gold nanoparticle solution was higher than in the tube of 2-5% cell suspension and monoclonal antibody. It has been observed that gold nanoparticle solution enhanced the reaction of agglutination 98% while LISS enhanced the agglutination only 60·8%. Employing a commercially available enhancing reagent, parallel samples confirmed results providing validation of the assay. It approximately costs $1 US dollars compared to $30 for a commercially available reagent. The low cost and yet effective time-consuming test for antibody screening is a practical and viable solution alternative way for performing in antibody screening test in resource limited countries. © 2016 British Blood Transfusion Society.
Stably Fluorescent Cell Line of Human Ovarian Epithelial Cancer Cells SK-OV-3ip-red.
Konovalova, E V; Shulga, A A; Chumakov, S P; Khodarovich, Yu M; Woo, Eui-Jeon; Deev, S M
2017-11-01
Stable red fluorescing line of human ovarian epithelial cancer cells SK-OV-3ip-red was generated expressing gene coding for protein TurboFP635 (Katushka) fluorescing in the far-red spectrum region with excitation and emission peaks at 588 and 635 nm, respectively. Fluorescence of SK-OV-3ip-red line remained high during long-term cell culturing and after cryogenic freezing. The obtained cell line SK-OV-3ip-red can serve a basis for a model of a scattered tumor with numerous/extended metastases and used both for testing anticancer drugs inhibiting metastasis growth and for non-invasive monitoring of the growth dynamics with high precision.
Tao, Yong; Rongin, Uwitije; Xing, Zhongwen
2016-01-01
The malaria-infected red blood cells experience a significant decrease in cell deformability and increase in cell membrane adhesion. Blood hemodynamics in microvessels is significantly affected by the alteration of the mechanical property as well as the aggregation of parasitized red blood cells. In this study, we aim to numerically study the connection between cell-level mechanobiological properties of human red blood cells and related malaria disease state by investigating the transport of multiple red blood cell aggregates passing through microchannels with symmetric stenosis. Effects of stenosis magnitude, aggregation strength, and cell deformability on cell rheology and flow characteristics were studied by a two-dimensional model using the fictitious domain-immersed boundary method. The results indicated that the motion and dissociation of red blood cell aggregates were influenced by these factors and the flow resistance increases with the increase of aggregating strength and cell stiffness. Further, the roughness of the velocity profile was enhanced by cell aggregation, which considerably affected the blood flow characteristics. The study may assist us in understanding cellular-level mechanisms in disease development. PMID:28105411
Seed viability detection using computerized false-color radiographic image enhancement
NASA Technical Reports Server (NTRS)
Vozzo, J. A.; Marko, Michael
1994-01-01
Seed radiographs are divided into density zones which are related to seed germination. The seeds which germinate have densities relating to false-color red. In turn, a seed sorter may be designed which rejects those seeds not having sufficient red to activate a gate along a moving belt containing the seed source. This results in separating only seeds with the preselected densities representing biological viability lending to germination. These selected seeds demand a higher market value. Actual false-coloring isn't required for a computer to distinguish the significant gray-zone range. This range can be predetermined and screened without the necessity of red imaging. Applying false-color enhancement is a means of emphasizing differences in densities of gray within any subject from photographic, radiographic, or video imaging. Within the 0-255 range of gray levels, colors can be assigned to any single level or group of gray levels. Densitometric values then become easily recognized colors which relate to the image density. Choosing a color to identify any given density allows separation by morphology or composition (form or function). Additionally, relative areas of each color are readily available for determining distribution of that density by comparison with other densities within the image.
USDA-ARS?s Scientific Manuscript database
Seedlings of three Eastern US forest species (red maple, northern red oak, and chestnut oak) were inoculated by applying Phytophthora ramorum sporangia to stems at different inoculum densities with and without wounding. Disease occurred in all treatments involving wounds, and no disease was observe...
P.W. Tooley; M. Browning; R.M. Leighty
2014-01-01
Seedlings of three Eastern US forest species Quercus rubra (northern red oak), Quercus prinus (chestnut oak) and Acer rubrum (red maple) were inoculated by applying Phytophthora ramorum sporangia to stems at different inoculum densities with and without wounding. Disease occurred in all...
Cardona, P-J; Soto, C Y; Martín, C; Giquel, B; Agustí, G; Andreu, Núria; Guirado, E; Sirakova, T; Kolattukudy, P; Julián, E; Luquin, M
2006-01-01
Searching for virulence marking tests for Mycobacterium tuberculosis, Dubos and Middlebrook reported in 1948 that in an alkaline aqueous solution of neutral-red, the cells of the virulent H37Rv M. tuberculosis strain fixed the dye and became red in color, whereas the cells of the avirulent H37Ra M. tuberculosis strain remained unstained. In the 1950 and 1960s, fresh isolates of M. tuberculosis were tested for this neutral-red cytochemical reaction and it was reported that they were neutral-red positive, whereas other mycobacteria of diverse environmental origins that were non-pathogenic for guinea pigs were neutral-red negative. However, neutral-red has not really been proven to be a virulence marker. To test if virulence is in fact correlated to neutral-red, we studied a clinical isolate of M. tuberculosis that was originally neutral-red positive but, after more than 1 year passing through culture mediums, turned neutral-red negative. We found that, in comparison to the original neutral-red positive strain, this neutral-red negative variant was attenuated in two murine models of experimental tuberculosis. Lipid analysis showed that this neutral-red negative natural mutant lost the capacity to synthesize pthiocerol dimycocerosates, a cell wall methyl-branched lipid that has been related to virulence in M. tuberculosis. We also studied the neutral-red of different gene-targeted M. tuberculosis mutants unable to produce pthiocerol dimycocerosates or other cell wall methyl-branched lipids such as sulfolipids, and polyacyltrehaloses. We found a negative neutral-red reaction in mutants that were deficient in more than one type of methyl-branched lipids. We conclude that neutral-red is indeed a marker of virulence and it indicates important perturbations in the external surface of M. tuberculosis cells.
2014-09-01
hybrid mice show a large population of cells that fluoresce with Tomato Red and few cells that fluoresce with GFP only or GFP/ Tomato Red double positive...percent of total cells Double Negative GFP Tomato Red Double Positive 15 Figure 3. Fluorescent activated cell sorting (FACS) shows slight...Negative Tomato Red Double Positive 17 Figure 5. Fluorescent activated cell sorting (FACS) shows no K14-GFP expressing cells and slight expression of
Red blood cell decreases of microgravity
NASA Technical Reports Server (NTRS)
Johnson, P. C.
1985-01-01
Postflight decreases in red blood cell mass (RBCM) have regularly been recorded after exposure to microgravity. These 5-25 percent decreases do not relate to the mission duration, workload, caloric intake or to the type of spacecraft used. The decrease is accompanied by normal red cell survivals, increased ferritin levels, normal radioactive iron studies, and increases in mean red blood cell volume. Comparable decreases in red blood cell mass are not found after bed rest, a commonly used simulation of the microgravity state. Inhibited bone marrow erythropoiesis has not been proven to date, although reticulocyte numbers in the peripheral circulation are decreased about 50 percent. To date, the cause of the microgravity induced decreases in RBCM is unknown. Increased splenic trapping of circulating red blood cells seem the most logical way to explain the results obtained.
Combinatorial Screening Of Inorganic And Organometallic Materials
Li, Yi , Li, Jing , Britton, Ted W.
2002-06-25
A method for differentiating and enumerating nucleated red blood cells in a blood sample is described. The method includes the steps of lysing red blood cells of a blood sample with a lytic reagent, measuring nucleated blood cells by DC impedance measurement in a non-focused flow aperture, differentiating nucleated red blood cells from other cell types, and reporting nucleated red blood cells in the blood sample. The method further includes subtracting nucleated red blood cells and other interference materials from the count of remaining blood cells, and reporting a corrected white blood cell count of the blood sample. Additionally, the method further includes measuring spectrophotometric absorbance of the sample mixture at a predetermined wavelength of a hemoglobin chromogen formed upon lysing the blood sample, and reporting hemoglobin concentration of the blood sample.
Bioleaching of rare earth and radioactive elements from red mud using Penicillium tricolor RM-10.
Qu, Yang; Lian, Bin
2013-05-01
The aim of this work is to investigate biological leaching of rare earth elements (REEs) and radioactive elements from red mud, and to evaluate the radioactivity of the bioleached red mud used for construction materials. A filamentous, acid-producing fungi named RM-10, identified as Penicillium tricolor, is isolated from red mud. In our bioleaching experiments by using RM-10, a total concentration of 2% (w/v) red mud under one-step bioleaching process was generally found to give the maximum leaching ratios of the REEs and radioactive elements. However, the highest extraction yields are achieved under two-step bioleaching process at 10% (w/v) pulp density. At pulp densities of 2% and 5% (w/v), red mud processed under both one- and two-step bioleaching can meet the radioactivity regulations in China. Copyright © 2013 Elsevier Ltd. All rights reserved.
Sickle red cell adhesion: many issues and some answers.
Kaul, D K
2008-01-01
Among multiple pathologies associated with sickle cell disease, sickle red cell-endothelial interaction has been implicated as a potential initiating mechanism in vaso-occlusive events that characterize this disease. Vast literature exists on various aspects of sickle red cell adhesion, but many issues remain unresolved, especially pertaining to the role of sickle red cell heterogeneity, the relative role of multiple adhesion mechanisms and targets of antiadhesive therapy. This review briefly analyzes these issues.
21 CFR 640.17 - Modifications for specific products.
Code of Federal Regulations, 2013 CFR
2013-04-01
... (CONTINUED) BIOLOGICS ADDITIONAL STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Red Blood Cells § 640.17 Modifications for specific products. Red Blood Cells Frozen: A cryophylactic substance may be added to the Red... safety, purity, and potency for Red Blood Cells, and that the frozen product will maintain those...
21 CFR 640.17 - Modifications for specific products.
Code of Federal Regulations, 2012 CFR
2012-04-01
... (CONTINUED) BIOLOGICS ADDITIONAL STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Red Blood Cells § 640.17 Modifications for specific products. Red Blood Cells Frozen: A cryophylactic substance may be added to the Red... safety, purity, and potency for Red Blood Cells, and that the frozen product will maintain those...
21 CFR 640.17 - Modifications for specific products.
Code of Federal Regulations, 2014 CFR
2014-04-01
... (CONTINUED) BIOLOGICS ADDITIONAL STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Red Blood Cells § 640.17 Modifications for specific products. Red Blood Cells Frozen: A cryophylactic substance may be added to the Red... safety, purity, and potency for Red Blood Cells, and that the frozen product will maintain those...
Mo, Solveig Sølverød; Urdahl, Anne Margrete; Madslien, Knut; Sunde, Marianne; Nesse, Live L; Slettemeås, Jannice Schau; Norström, Madelaine
2018-01-01
The objective of this study was to estimate and compare the occurrence of AMR in wild red foxes in relation to human population densities. Samples from wild red foxes (n = 528) included in the Norwegian monitoring programme on antimicrobial resistance in bacteria from food, feed and animals were included. All samples were divided into three different groups based on population density in the municipality where the foxes were hunted. Of the 528 samples included, 108 (20.5%), 328 (62.1%) and 92 (17.4%) originated from areas with low, medium and high population density, respectively. A single faecal swab was collected from each fox. All samples were plated out on a selective medium for Enterobacteriaceae for culturing followed by inclusion and susceptibility testing of one randomly selected Escherichia coli to assess the overall occurrence of AMR in the Gram-negative bacterial population. Furthermore, the samples were subjected to selective screening for detection of E. coli displaying resistance towards extended-spectrum cephalosporins and fluoroquinolones. In addition, a subset of samples (n = 387) were subjected to selective culturing to detect E. coli resistant to carbapenems and colistin, and enterococci resistant to vancomycin. Of these, 98 (25.3%), 200 (51.7%) and 89 (23.0%) originated from areas with low, medium and high population density, respectively. Overall, the occurrence of AMR in indicator E. coli from wild red foxes originating from areas with different human population densities in Norway was low to moderate (8.8%). The total occurrence of AMR was significantly higher; χ2 (1,N = 336) = 6.53, p = 0.01 in areas with high population density compared to areas with medium population density. Similarly, the occurrence of fluoroquinolone resistant E. coli isolated using selective detection methods was low in areas with low population density and more common in areas with medium or high population density. In conclusion, we found indications that occurrence of AMR in wild red foxes in Norway is associated with human population density. Foxes living in urban areas are more likely to be exposed to AMR bacteria and resistance drivers from food waste, garbage, sewage, waste water and consumption of contaminated prey compared to foxes living in remote areas. The homerange of red fox has been shown to be limited thereby the red fox constitutes a good sentinel for monitoring antimicrobial resistance in the environment. Continuous monitoring on the occurrence of AMR in different wild species, ecological niches and geographical areas can facilitate an increased understanding of the environmental burden of AMR in the environment. Such information is needed to further assess the impact for humans, and enables implementation of possible control measures for AMR in humans, animals and the environment in a true "One Health" approach.
Opto-fluidics based microscopy and flow cytometry on a cell phone for blood analysis.
Zhu, Hongying; Ozcan, Aydogan
2015-01-01
Blood analysis is one of the most important clinical tests for medical diagnosis. Flow cytometry and optical microscopy are widely used techniques to perform blood analysis and therefore cost-effective translation of these technologies to resource limited settings is critical for various global health as well as telemedicine applications. In this chapter, we review our recent progress on the integration of imaging flow cytometry and fluorescent microscopy on a cell phone using compact, light-weight and cost-effective opto-fluidic attachments integrated onto the camera module of a smartphone. In our cell-phone based opto-fluidic imaging cytometry design, fluorescently labeled cells are delivered into the imaging area using a disposable micro-fluidic chip that is positioned above the existing camera unit of the cell phone. Battery powered light-emitting diodes (LEDs) are butt-coupled to the sides of this micro-fluidic chip without any lenses, which effectively acts as a multimode slab waveguide, where the excitation light is guided to excite the fluorescent targets within the micro-fluidic chip. Since the excitation light propagates perpendicular to the detection path, an inexpensive plastic absorption filter is able to reject most of the scattered light and create a decent dark-field background for fluorescent imaging. With this excitation geometry, the cell-phone camera can record fluorescent movies of the particles/cells as they are flowing through the microchannel. The digital frames of these fluorescent movies are then rapidly processed to quantify the count and the density of the labeled particles/cells within the solution under test. With a similar opto-fluidic design, we have recently demonstrated imaging and automated counting of stationary blood cells (e.g., labeled white blood cells or unlabeled red blood cells) loaded within a disposable cell counting chamber. We tested the performance of this cell-phone based imaging cytometry and blood analysis platform by measuring the density of red and white blood cells as well as hemoglobin concentration in human blood samples, which showed a good match to our measurement results obtained using a commercially available hematology analyzer. Such a cell-phone enabled opto-fluidics microscopy, flow cytometry, and blood analysis platform could be especially useful for various telemedicine applications in remote and resource-limited settings.
Whey proteins protect more than red meat against azoxymethane induced ACF in Wistar rats.
Belobrajdic, D P; McIntosh, G H; Owens, J A
2003-07-30
Protein type and density have been shown to influence colon cancer risk using a carcinogen-induced rat model. It is suggested that red meat may promote colon cancer risk more than whey proteins. The aim of this study was to evaluate the influence of red meat, whey protein and their density in the diet on the number of aberrant crypt foci (ACF), preneoplastic markers in Wistar rats. The sources of protein, red meat as barbecued kangaroo muscle meat, and whey protein concentrate were fed to rats to provide 8, 16 and 32% protein by weight in a modified AIN-93 diet with low fiber, low calcium and high polyunsaturated fat. Adult Wistar rats (13 weeks of age) were fed these diets for 4 weeks and then two s.c. injections of azoxymethane, 15 mg/kg BW, were administered 1 week apart. Diets were fed for a further 8 weeks, rats were then killed, their colons fixed in formalin saline and stained with methylene blue to quantify ACF number. Fecal samples were collected and the fecal water was isolated for quantification of heme and thiobarbituric acid reactive substances. Increasing red meat density correlated positively, while increasing dairy protein density correlated negatively with rate of weight gain (p<0.05). Dietary intake was not significantly affected by protein type or density. The 32% whey protein group had significantly less ACF in the proximal colon in comparison to the 16 and 32% red meat groups (p<0.05). This reduction in ACF number in the whey protein group may be caused by hormones associated with the reduction in weight gain, and/or by components of whey protein concentrate such as cysteine, lactose and conjugated linoleic acid which have been shown to have anti-cancer effects. Using ACF number as an index, whey protein appeared to be more protective than red meat.
Soil-Water Characteristic Curves of Red Clay treated by Ionic Soil Stabilizer
NASA Astrophysics Data System (ADS)
Cui, D.; Xiang, W.
2009-12-01
The relationship of red clay particle with water is an important factor to produce geological disaster and environmental damage. In order to reduce the role of adsorbed water of red clay in WuHan, Ionic Soil Stabilizer (ISS) was used to treat the red clay. Soil Moisture Equipment made in U.S.A was used to measure soil-water characteristic curve of red clay both in natural and stabilized conditions in the suction range of 0-500kPa. The SWCC results were used to interpret the red clay behavior due to stabilizer treatment. In addition, relationship were compared between the basic soil and stabilizer properties such as water content, dry density, liquid limit, plastic limit, moisture absorption rate and stabilizer dosages. The analysis showed that the particle density and specific surface area increase, the dehydration rate slows and the thickness of water film thins after treatment with Ionic Soil Stabilizer. After treatment with the ISS, the geological disasters caused by the adsorbed water of red clay can be effectively inhibited.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bertoncello, I.; Hodgson, G.S.; Bradley, T.R.
A multiparameter cell separative procedure is described that enables normal transplantable hemopoietic stem cells that preferentially home to the marrow of lethally irradiated mice to be enriched and separated from the majority of spleen colony-forming cells that are assayed 13 days after transplantation (CFU-S13). First, bone marrow cells are centrifuged in a discontinuous bovine serum albumin gradient. Low-density cells are harvested and labeled with the supravital cationic fluorochrome rhodamine 123 (Rh123). Labeled cells are analyzed using a fluorescence-activated cell sorter, and cells are sorted on the basis of relative Rh123 fluorescence within a predetermined forward versus 90 degrees red lightmore » scatter window that has been optimized for the recovery and enrichment of cells with marrow repopulating ability (MRA). Cells with MRA were characterized by relatively low Rh123 fluorescence and could be separated from a fraction that fluoresced more intensely and contained the majority of CFU-S13 but low MRA. Cells with platelet repopulating ability cofractionate with MRA whereas cells with erythroid repopulating ability remain associated with CFU-S13.« less
Benjamin, N; Robinson, B F; Graham, J G; Wilson, R B
1990-06-01
The cholesterol:phospholipid ratio was measured in platelet plasma membrane, red blood cell (RBC) membranes, low density lipoprotein (LDL) and whole plasma in patients with primary hypertension and in matched normal controls. The cholesterol:phospholipid ratio was raised in the platelet membrane from hypertensive patients compared with that from normal controls (0.65 +/- 0.03 vs 0.53 +/- 0.02: mean +/- SEM; P less than 0.01). The ratio observed in RBC membranes, LDL and whole blood was similar in the two groups. If this abnormality in the lipid composition of platelet plasma membrane is present in other cells it could account for some of the changes in cell membrane function that have been described in hypertension.
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 < 0.001) and permitted a higher sickle hemoglobin level decrease per volume removed (p < 0.001), while hemoglobin and hematocrit remained stable. Ferritin levels on chronic patients decreased 54%. Most frequent concern was catheter outflow obstruction on manual-red blood cell exchange and access alarm on automated-red blood cell exchange. No major complication or alloimunization was recorded. Automated-red blood cell exchange decreased sickle hemoglobin levels more efficiently than manual procedure in the setting of acute and chronic complications of sickle cell disease, with minor technical concerns mainly due to vascular access. The threshold of sickle hemoglobin should be individualized for clinical and hematological goals. In our cohort of young patients, the need for an acceptable venous access was a limiting factor, but iron-overload was avoided. Automated red blood cell exchange is safe and well tolerated. It permits a higher sickle hemoglobin removal efficacy, better volume status control and iron-overload avoidance.
NASA Astrophysics Data System (ADS)
Lin, Hong; Wang, Xinming; Liang, Kun
2010-10-01
For monitoring and forecasting of the ocean red tide in real time, a marine environment monitoring technology based on the double-wavelength airborne lidar system is proposed. An airborne lidar is father more efficient than the traditional measure technology by the boat. At the same time, this technology can detect multi-parameter about the ocean red tide by using the double-wavelength lidar.It not only can use the infrared laser to detect the scattering signal under the water and gain the information about the red tise's density and size, but also can use the blue-green laser to detect the Brillouin scattering signal and deduce the temperature and salinity of the seawater.The red tide's density detecting model is firstly established by introducing the concept about the red tide scattering coefficient based on the Mie scattering theory. From the Brillouin scattering theory, the relationship about the blue-green laser's Brillouin scattering frequency shift value and power value with the seawater temperature and salinity is found. Then, the detecting mode1 of the saewater temperature and salinity can be established. The value of the red tide infrared scattering signal is evaluated by the simulation, and therefore the red tide particles' density can be known. At the same time, the blue-green laser's Brillouin scattering frequency shift value and power value are evaluated by simulating, and the temperature and salinity of the seawater can be known. Baed on the multi-parameters, the ocean red tide's growth can be monitored and forecasted.
Improved PEDOT:PSS/c-Si hybrid solar cell using inverted structure and effective passivation
Zhang, Xisheng; Yang, Dong; Yang, Zhou; Guo, Xiaojia; Liu, Bin; Ren, Xiaodong; Liu, Shengzhong (Frank)
2016-01-01
The PEDOT:PSS is often used as the window layer in the normal structured PEDOT:PSS/c-Si hybrid solar cell (HSC), leading to significantly reduced response, especially in red and near-infrared region. By depositing the PEDOT:PSS on the rear side of the c-Si wafer, we developed an inverted structured HSC with much higher solar cell response in the red and near-infrared spectrum. Passivating the other side with hydrogenated amorphous silicon (a-Si:H) before electrode deposition, the minority carrier lifetime has been significantly increased and the power conversion efficiency (PCE) of the inverted HSC is improved to as high as 16.1% with an open-circuit voltage (Voc) of 634 mV, fill factor (FF) of 70.5%, and short-circuit current density (Jsc) of 36.2 mA cm−2, an improvement of 33% over the control device. The improvements are ascribed to inverted configuration and a-Si:H passivation, which can increase photon carrier generation and reduce carrier recombination, respectively. Both of them will benefit the photovoltaic performance and should be considered as effective design strategies to improve the performance of organic/c-Si HSCs. PMID:27725714
Parallel Microchannel-Based Measurements of Individual Erythrocyte Areas and Volumes
Gifford, Sean C.; Frank, Michael G.; Derganc, Jure; Gabel, Christopher; Austin, Robert H.; Yoshida, Tatsuro; Bitensky, Mark W.
2003-01-01
We describe a microchannel device which utilizes a novel approach to obtain area and volume measurements on many individual red blood cells. Red cells are aspirated into the microchannels much as a single red blood cell is aspirated into a micropipette. Inasmuch as there are thousands of identical microchannels with defined geometry, data for many individual red cells can be rapidly acquired, and the fundamental heterogeneity of cell membrane biophysics can be analyzed. Fluorescent labels can be used to quantify red cell surface and cytosolic features of interest simultaneously with the measurement of area and volume for a given cell. Experiments that demonstrate and evaluate the microchannel measuring capabilities are presented and potential improvements and extensions are discussed. PMID:12524315
Irani, Mehraboon S; Karafin, Matthew S; Ernster, Luke
2017-02-01
A red cell exchange was performed to prevent a potentially fatal hemolytic transfusion reaction in a patient with anti-e who was transfused with e-antigen unscreened red blood cells during liver transplant surgery. A 64-year-old woman with cirrhosis due to hepatitis C was scheduled to receive a liver transplant. She had a previously documented anti-e, an antibody to the Rh(e)-antigen that is known to cause delayed hemolytic transfusion reactions. Pre-operatively and intra-operatively, she had massive hemorrhage which required transfusion of 34 e-antigen unscreened red blood cells (RBCs) most of which were incompatible. The hemoglobin dropped from 9.1 g/dL on post-operative day (POD)1 to 6.6 g/dL on POD6, with no evidence of blood loss. The bilirubin also increased from 5.0 mg/dL on POD 1 to 11.0 mg/dL on POD 6. As she was also becoming more hemodynamically unstable, a red cell exchange with 10 units of e-negative RBCs was performed on POD 6. She improved clinically and was extubated the following day. A few residual transfused e-positive red cells were detected after the red cell exchange until POD 13. This case illustrates how a red cell exchange can mitigate the potentially harmful effects of a delayed hemolytic transfusion reaction caused by red cell antibodies. With massive intraoperative blood loss it may not be possible to have antigen-negative RBCs immediately available, particularly for the e-antigen, which is present in 98% of the donor population. The ability to perform such a procedure may be life-saving in such patients. J. Clin. Apheresis 32:59-61, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.
Effects of helicopter transport on red blood cell components.
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.
Effects of helicopter transport on red blood cell components
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
Development of a Microfluidic Platform to Analyze Evolution of Programmed Bacterial Death
2015-12-20
We modulated the final concentrations of 6- APA and IPTG in droplets by varying their concentrations in the injection phase. At 25µg/ml 6- APA , the...in comparison, when the population was induced by 1mM IPTG, the cells grew to a higher density; this is due to the degradation of 6- APA by BlaM (red...line in Figure 4A). Similarly, when the concentration of 6- APA was increased to Surfactant)molecules) Stable)droplets) +) +) Droplet)injec6on
Effects of acute hypoxic exposure on oxygen affinity of human red blood cells.
Chowdhury, Aniket; Dasgupta, Raktim
2017-01-20
Adaptation of red blood cells subjected to acute hypoxia, crucial for managing high altitude syndrome and pulmonary diseases, has been investigated. For this, red blood cells were exposed to the acute hypoxic condition by purging nitrogen over increasing time periods from 15 to 60 min and thereafter equilibrated with atmospheric oxygen for 10 min. Raman spectra of these red blood cells were then recorded and analyzed to look for changes in the level of oxygenation compared to unexposed cells. A decreasing oxygen affinity for the cells was observed with increasing time of exposure to the hypoxic condition. This change in oxygen affinity for the red blood cells may result from metabolic adjustment of the cells under the hypoxic condition to promote increased concentration of intracellular 2, 3-diphosphoglycerate.
Udani, M; Zen, Q; Cottman, M; Leonard, N; Jefferson, S; Daymont, C; Truskey, G; Telen, M J
1998-01-01
Sickle red cells bind significant amounts of soluble laminin, whereas normal red cells do not. Solid phase assays demonstrate that B-CAM/LU binds laminin on intact sickle red cells and that red cell B-CAM/LU binds immobilized laminin, whereas another putative laminin binding protein, CD44, does not. Ligand blots also identify B-CAM/LU as the only erythrocyte membrane protein(s) that binds laminin. Finally, transfection of murine erythroleukemia cells with human B-CAM cDNA induces binding of both soluble and immobilized laminin. Thus, B-CAM/LU appears to be the major laminin-binding protein of sickle red cells. Previously reported overexpression of B-CAM/LU by epithelial cancer cells suggests that this protein may also serve as a laminin receptor in malignant tumors. PMID:9616226
Ishiguro, E E; Ainsworth, T; Trust, T J; Kay, W W
1985-01-01
Strains of the fish pathogen Aeromonas salmonicida which possess the cell surface protein array known as the A-layer (A+) involved in virulence formed deep red colonies on tryptic soy agar containing 30 micrograms of Congo red per ml. These were readily distinguished from colorless or light orange colonies of avirulent mutants lacking A-layer (A-). The utility of Congo red agar for quantifying A+ and A- cells in the routine assessment of culture virulence was demonstrated. Intact A+ cells adsorbed Congo red, whereas A- mutants did not bind Congo red unless first permeabilized with EDTA. The dye-binding component of A+ cells was shown to be the 50,000-Mr A-protein component of the surface array. Purified A-protein avidly bound Congo red at a dye-to-protein molar ratio of about 30 by a nonspecific hydrophobic mechanism enhanced by high salt concentrations. Neither A+ nor A- cells adsorbed to Congo red-Sepharose columns at low salt concentrations. On the other hand, A+ (but not A-) cells were avidly bound at high salt concentrations. Images PMID:3934141
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.
Measuring skewness of red blood cell deformability distribution by laser ektacytometry
DOE Office of Scientific and Technical Information (OSTI.GOV)
Nikitin, S Yu; Priezzhev, A V; Lugovtsov, A E
An algorithm is proposed for measuring the parameters of red blood cell deformability distribution based on laser diffractometry of red blood cells in shear flow (ektacytometry). The algorithm is tested on specially prepared samples of rat blood. In these experiments we succeeded in measuring the mean deformability, deformability variance and skewness of red blood cell deformability distribution with errors of 10%, 15% and 35%, respectively. (laser biophotonics)
[Correlation between red blood cell count and liver function status].
Xie, Xiaomeng; Wang, Leijie; Yao, Mingjie; Wen, Xiajie; Chen, Xiangmei; You, Hong; Jia, Jidong; Zhao, Jingmin; Lu, Fengmin
2016-02-01
To investigate the changes in red blood cell count in patients with different liver diseases and the correlation between red blood cell count and degree of liver damage. The clinical data of 1427 patients with primary liver cancer, 172 patients with liver cirrhosis, and 185 patients with hepatitis were collected, and the Child-Pugh class was determined for all patients. The differences in red blood cell count between patients with different liver diseases were retrospectively analyzed, and the correlation between red blood cell count and liver function status was investigated. The Mann-Whitney U test, Kruskal-Wallis H test, rank sum test, Spearman rank sum correlation test, and chi-square test were performed for different types of data. Red blood cell count showed significant differences between patients with chronic hepatitis, liver cancer, and liver cirrhosis and was highest in patients with chronic hepatitis and lowest in patients with liver cirrhosis (P < 0.05). In the patients with liver cirrhosis, red blood cell count tended to decrease in patients with a higher Child-Pugh class (P < 0.05). For patients with liver cirrhosis, red blood cell count can reflect the degree of liver damage, which may contribute to an improved liver function prediction model for these patients.
Studies on the erythron and the ferrokinetic responses in beagles adapted to hypergravity
NASA Technical Reports Server (NTRS)
Beckman, D. A.; Evans, J. W.; Oyama, J.
1978-01-01
Red cell survival, ferrokinetics, and hematologic parameters were investigated in beagle dogs exposed to chronic hypergravity (2.6 Gx). Ineffective erythropoiesis, red cell mass, plasma volume, and Cr-51-elution were significantly increased; maximum Fe-59 incorporation was decreased; and there was no change in the mean erythrocyte life span following autologous injection of Cr-51-labeled red cells and Fe-59-labeled transferrin. Red cell count, F(cells), total body hemoglobin (Hb), susceptability to osmotic lysis, and differential reticulocyte count were increased. White blood cell count, venous blood %Hb, mean cell volume, mean cell Hb, mean cell Hb concentration, and serum iron were decreased. No changes were observed for body mass, mg Fe per g Hb, iron binding capacity, percent saturation of iron carrying capacity, or the electrophoretic mobility of purified Hb. This study indicated that chronic exposure to hypergravity induced changes in red cell size, volume, total mass, and membrane permeability.
Rice, Lawrence; Alfrey, Clarence P
2005-01-01
We have uncovered a physiologic process which negatively regulates the red cell mass by selectively hemolyzing young circulating red blood cells. This allows fine control of the number of circulating red blood cells under steady-state conditions and relatively rapid adaptation to new environments. Neocytolysis is initiated by a fall in erythropoietin levels, so this hormone remains the major regulator of red cell mass both with anemia and with red cell excess. Physiologic situations in which there is increased neocytolysis include the emergence of newborns from the hypoxic uterine environment and the descent of polycythemic high-altitude dwellers to sea level. The process first became apparent while investigating the mechanism of the anemia that invariably occurs after spaceflight. Astronauts experience acute central plethora on entering microgravity resulting in erythropoietin suppression and neocytolysis, but the reduced blood volume and red cell mass become suddenly maladaptive on re-entry to earth's gravity. The pathologic erythropoietin deficiency of renal disease precipitates neocytolysis, which explains the prolongation of red cell survival consistently resulting from erythropoietin therapy and points to optimally efficient erythropoietin dosing schedules. Implications should extend to a number of other physiologic and pathologic situations including polycythemias, hemolytic anemias, 'blood-doping' by elite athletes, and oxygen therapy. It is likely that erythropoietin influences endothelial cells which in turn signal reticuloendothelial phagocytes to destroy or permit the survival of young red cells marked by surface molecules. Ongoing studies to identify the molecular targets and cytokine intermediaries should facilitate detection, dissection and eventual therapeutic manipulation of the process. Copyright (c) 2005 S. Karger AG, Basel.
Blood bank issues associated with red cell exchanges in sickle cell disease.
Sarode, Ravindra; Altuntas, Fevzi
2006-12-01
Sickle cell disease (SCD) patients are prone to develop complications that include stroke, acute chest syndrome, and other crises. Some of these complications require chronic transfusion therapy or red cell exchange (RCE), either for therapeutic or prophylactic reasons. Due to a discrepancy of red cell antigens between African Americans and Caucasians (majority blood donors), the incidence of alloantibody formation is very high, which makes it difficult to find compatible red cell units, especially for urgent RCE. Some of the above conditions require immediate oxygen delivery to the tissues. Thus, SCD patients undergoing RCE should receive red blood cells with special attributes that include matching for Rh and Kell blood group antigens; RBCs should be fresh in order to provide (1) immediate oxygen delivery and (2) longer surviving cells to reduce the interval between RCE. Also, these units should be pre-storage leukoreduced to prevent febrile non-hemolytic reactions and screened for sickle cell traits to avoid transfusing red cells containing HbS. This requires a concerted effort between the apheresis unit, the local blood bank, and the central blood supplier.
PARABIOTIC INTOXICATION. II. THE DISTRIBUTION AND SURVIVAL OF Cr$sup 51$- LABELED RED BLOOD CELLS
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tokuda, S.; MacGillivray, M.H.
1962-04-01
The anemia and polycythemia in parent-to-F/sub 1/ parabiotic intoxication in mice were studied using Cr/sup 51/- and Fe/sup 59/ labeled red blood cells. It was observed that the anemia and polycythemia result from a shift in red cell mass from the hybrid into its parent strain partner. Because crosscirculation was observed between the parabionts during the anemia and polycythemia, the shift is attributed to unequal cross transfusion between the parabionts. There was neither preferential selection nor preferential destruction of either parental or hybrid red cells during the shift in red cell mass. (auth)
Red Blood Cell Count Automation Using Microscopic Hyperspectral Imaging Technology.
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.
Breeding biology and nest-site selection of red-tailed hawks in an altered desert grassland
Hobbs, R.J.; DeStefano, S.; Halvorson, W.L.
2006-01-01
Red-tailed Hawks (Buteo jamaicensis) have expanded their range as trees have invaded formerly-open grasslands. Desert grasslands of southern Arizona have been invaded by mesquite trees (Prosopis velutina) since Anglo-American settlement and now support a large population of Red-tailed Hawks. We studied a population of Red-tailed Hawks in an altered desert grassland in southern Arizona. Our objectives were to determine what environmental characteristics influence Red-tailed Hawk habitat selection in mesquite-invaded desert grasslands and to evaluate the habitat quality of these grasslands for Red-tailed Hawks based on nesting density, nest success, and productivity. Red-tailed Hawks had 86% (95% C.I. = 73-99) nest success and 1.82 young per breeding pair (95% C.I. = 1.41-2.23). Nesting density was 0.15 (95% CI = 0.08-0.21) breeding pairs/km2 and the mean nearest-neighbor distance was 1.95 km (95% C.I. = 1.74-2.16). Red-tailed Hawks selected nest-sites with taller nest-trees and greater tree height and cover than were available at random. Mesquite trees in desert grasslands provide abundant potential nesting structures for Red-tailed Hawks. ?? 2006 The Raptor Research Foundation, Inc.
NASA Astrophysics Data System (ADS)
Joglekar, M.; Shah, H.; Trivedi, V.; Mahajan, S.; Chhaniwal, V.; Leitgeb, R.; Javidi, B.; Anand, A.
2017-07-01
Adequate supply of oxygen to the body is the most essential requirement. In vertebrate species this function is performed by Hemoglobin contained in red blood cells. The mass concentration of the Hb determines the oxygen carrying capacity of the blood. Thus it becomes necessary to determine its concentration in the blood, which helps in monitoring the health of a person. If the amount of Hb crosses certain range, then it is considered critical. As the Hb constitutes upto 96% of red blood cells dry content, it would be interesting to examine various physical and mechanical parameters of RBCs which depends upon its concentration. Various diseases bring about significant variation in the amount of hemoglobin which may alter certain parameters of the RBC such as surface area, volume, membrane fluctuation etc. The study of the variations of these parameters may be helpful in determining Hb content which will reflect the state of health of a human body leading to disease diagnosis. Any increase or decrease in the amount of Hb will change the density and hence the optical thickness of the RBCs, which affects the cell membrane and thereby changing its mechanical and physical properties. Here we describe the use of lateral shearing digital holographic microscope for quantifying the cell parameters for studying the change in biophysical properties of cells due to variation in hemoglobin concentration.
Congo red modulates ACh-induced Ca2+ oscillations in single pancreatic acinar cells of mice
Huang, Ze-bing; Wang, Hai-yan; Sun, Na-na; Wang, Jing-ke; Zhao, Meng-qin; Shen, Jian-xin; Gao, Ming; Hammer, Ronald P; Fan, Xue-gong; Wu, Jie
2014-01-01
Aim: Congo red, a secondary diazo dye, is usually used as an indicator for the presence of amyloid fibrils. Recent studies show that congo red exerts neuroprotective effects in a variety of models of neurodegenerative diseases. However, its pharmacological profile remains unknown. In this study, we investigated the effects of congo red on ACh-induced Ca2+ oscillations in mouse pancreatic acinar cells in vitro. Methods: Acutely dissociated pancreatic acinar cells of mice were prepared. A U-tube drug application system was used to deliver drugs into the bath. Intracellular Ca2+ oscillations were monitored by whole-cell recording of Ca2+-activated Cl− currents and by using confocal Ca2+ imaging. For intracellular drug application, the drug was added in pipette solution and diffused into cell after the whole-cell configuration was established. Results: Bath application of ACh (10 nmol/L) induced typical Ca2+ oscillations in dissociated pancreatic acinar cells. Addition of congo red (1, 10, 100 μmol/L) dose-dependently enhanced Ach-induced Ca2+ oscillations, but congo red alone did not induce any detectable response. Furthermore, this enhancement depended on the concentrations of ACh: congo red markedly enhanced the Ca2+ oscillations induced by ACh (10–30 nmol/L), but did not alter the Ca2+ oscillations induced by ACh (100–10000 nmol/L). Congo red also enhanced the Ca2+ oscillations induced by bath application of IP3 (30 μmol/L). Intracellular application of congo red failed to alter ACh-induced Ca2+ oscillations. Conclusion: Congo red significantly modulates intracellular Ca2+ signaling in pancreatic acinar cells, and this pharmacological effect should be fully considered when developing congo red as a novel therapeutic drug. PMID:25345744
Interaction between phloretin and the red blood cell membrane
1976-01-01
Phloretin binding to red blood cell components has been characterized at pH6, where binding and inhibitory potency are maximal. Binding to intact red cells and to purified hemoglobin are nonsaturated processes approximately equal in magnitude, which strongly suggests that most of the red cell binding may be ascribed to hemoglobin. This conclusion is supported by the fact that homoglobin-free red cell ghosts can bind only 10% as much phloretin as an equivalent number of red cells. The permeability of the red cell membrane to phloretin has been determined by a direct measurement at the time-course of the phloretin uptake. At a 2% hematocrit, the half time for phloretin uptake is 8.7s, corresponding to a permeability coefficient of 2 x 10(-4) cm/s. The concentration dependence of the binding to ghosts reveals two saturable components. Phloretin binds with high affinity (K diss = 1.5 muM) to about 2.5 x 10(6) sites per cell; it also binds with lower affinity (Kdiss = 54 muM) to a second (5.5 x 10(7) per cell) set of sites. In sonicated total lipid extracts of red cell ghosts, phloretin binding consists of a single, saturable component. Its affinity and total number of sites are not significantly different from those of the low affinity binding process in ghosts. No high affinity binding of phloretin is exhibited by the red cell lipid extracts. Therefore, the high affinity phloretin binding sites are related to membrane proteins, and the low affinity sites result from phloretin binding to lipid. The identification of these two types of binding sites allows phloretin effects on protein-mediated transport processes to be distinguished from effects on the lipid region of the membrane. PMID:5575
Red cell distribution width does not predict stroke severity or functional outcome.
Ntaios, George; Gurer, Ozgur; Faouzi, Mohamed; Aubert, Carole; Michel, Patrik
2012-01-01
Red cell distribution width was recently identified as a predictor of cardiovascular and all-cause mortality in patients with previous stroke. Red cell distribution width is also higher in patients with stroke compared with those without. However, there are no data on the association of red cell distribution width, assessed during the acute phase of ischemic stroke, with stroke severity and functional outcome. In the present study, we sought to investigate this relationship and ascertain the main determinants of red cell distribution width in this population. We used data from the Acute Stroke Registry and Analysis of Lausanne for patients between January 2003 and December 2008. Red cell distribution width was generated at admission by the Sysmex XE-2100 automated cell counter from ethylene diamine tetraacetic acid blood samples stored at room temperature until measurement. An χ(2) -test was performed to compare frequencies of categorical variables between different red cell distribution width quartiles, and one-way analysis of variance for continuous variables. The effect of red cell distribution width on severity and functional outcome was investigated in univariate and multivariate robust regression analysis. Level of significance was set at 95%. There were 1504 patients (72±15·76 years, 43·9% females) included in the analysis. Red cell distribution width was significantly associated to NIHSS (β-value=0·24, P=0·01) and functional outcome (odds ratio=10·73 for poor outcome, P<0·001) at univariate analysis but not multivariate. Prehospital Rankin score (β=0·19, P<0·001), serum creatinine (β=0·008, P<0·001), hemoglobin (β=-0·009, P<0·001), mean platelet volume (β=0·09, P<0·05), age (β=0·02, P<0·001), low ejection fraction (β=0·66, P<0·001) and antihypertensive treatment (β=0·32, P<0·001) were independent determinants of red cell distribution width. Red cell distribution width, assessed during the early phase of acute ischemic stroke, does not predict severity or functional outcome. © 2011 The Authors. International Journal of Stroke © 2011 World Stroke Organization.
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 content should be used.
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.
Human spleen and red blood cells
NASA Astrophysics Data System (ADS)
Pivkin, Igor; Peng, Zhangli; Karniadakis, George; Buffet, Pierre; Dao, Ming
2016-11-01
Spleen plays multiple roles in the human body. Among them is removal of old and altered red blood cells (RBCs), which is done by filtering cells through the endothelial slits, small micron-sized openings. There is currently no experimental technique available that allows us to observe RBC passage through the slits. It was previously noticed that people without a spleen have less deformable red blood cells, indicating that the spleen may play a role in defining the size and shape of red blood cells. We used detailed RBC model implemented within the Dissipative Particle Dynamics (DPD) simulation framework to study the filter function of the spleen. Our results demonstrate that spleen indeed plays major role in defining the size and shape of the healthy human red blood cells.
Role of red cells and plasma composition on blood sessile droplet evaporation
NASA Astrophysics Data System (ADS)
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.
Lew, Virgilio L; Tiffert, Teresa
2017-01-01
In a healthy adult, the transport of O 2 and CO 2 between lungs and tissues is performed by about 2 · 10 13 red blood cells, of which around 1.7 · 10 11 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 P sickle in sickle cells, and the Ca 2+ -sensitive, K + -selective Gardos channel, can implement red blood cell volume stability around the optimal-volume-ratio range, as required for extended circulatory longevity.
Lew, Virgilio L.; Tiffert, Teresa
2017-01-01
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. PMID:29311949
Mechanoreceptor Cells on the Tertiary Pulvini of Mimosa pudica L.
Világi, Ildikó; Varró, Petra; Kristóf, Zoltán
2007-01-01
Special red cells were found on the adaxial surface of tertiary pulvini of Mimosa pudica and experiments performed to determine the origin and function of these cells. Using anatomical (light, scanning electron and transmission electron microscopy) and electrophysiological techniques, we have demonstrated that these red cells are real mechanoreceptor cells. They can generate receptor potential following mechanical stimuli and they are in connection with excitable motor cells (through plasmodesmata). We also provide evidence that these red cells are derived from stomatal subsidiary cells and not guard cells. As histochemical studies show red cells contain tannin, which is important in development of action potentials and movements of plants. These cells could be one of unidentified mechanoreceptors of mimosa. PMID:19517007
Code of Federal Regulations, 2010 CFR
2010-04-01
... STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Red Blood Cells § 640.16 Processing. (a) Separation. Within the..., Red Blood Cells may be prepared either by centrifugation, done in a manner that will not tend to... sufficient to insure optimal cell preservation shall be left with the red cells except when a cryoprotective...
Phototoxic effects of lysosome-associated genetically encoded photosensitizer KillerRed
NASA Astrophysics Data System (ADS)
Serebrovskaya, Ekaterina O.; Ryumina, Alina P.; Boulina, Maria E.; Shirmanova, Marina V.; Zagaynova, Elena V.; Bogdanova, Ekaterina A.; Lukyanov, Sergey A.; Lukyanov, Konstantin A.
2014-07-01
KillerRed is a unique phototoxic red fluorescent protein that can be used to induce local oxidative stress by green-orange light illumination. Here we studied phototoxicity of KillerRed targeted to cytoplasmic surface of lysosomes via fusion with Rab7, a small GTPase that is known to be attached to membranes of late endosomes and lysosomes. It was found that lysosome-associated KillerRed ensures efficient light-induced cell death similar to previously reported mitochondria- and plasma membrane-localized KillerRed. Inhibitory analysis demonstrated that lysosomal cathepsins play an important role in the manifestation of KillerRed-Rab7 phototoxicity. Time-lapse monitoring of cell morphology, membrane integrity, and nuclei shape allowed us to conclude that KillerRed-Rab7-mediated cell death occurs via necrosis at high light intensity or via apoptosis at lower light intensity. Potentially, KillerRed-Rab7 can be used as an optogenetic tool to direct target cell populations to either apoptosis or necrosis.
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.
Liu, Zun Chang; Chang, Thomas M.S.
2012-01-01
This study is to investigate the long-term effects of nanodimension PEG-PLA artificial red blood cells containing hemoglobin and red blood cell enzymes on the liver and spleen after 1/3 blood volume top loading in rats. The experimental rats received one of the following infusions: Nano artificial red blood cells in Ringer lactate, Ringer lactate, stroma-free hemoglobin, polyhemoglobin, and autologous rat whole blood. Blood samples were taken before infusions and on days 1, 7, and 21 after infusions for analysis. Nano artificial red blood cells, polyhemoglobin, Ringer lactate and rat red blood cells did not have any significant adverse effects on alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, creatine kinase, amylase and creatine kinase. On the other hand, stroma-free hemoglobin induced significant adverse effects on liver as shown by elevation in alanine aminotransferase and aspartate aminotransferase throughout the 21 days. On day 21 after infusions rats were sacrificed and livers and spleens were excised for histological examination. Nano artificial red blood cells, polyhemoglobin, Ringer lactate and rat red blood cells did not cause any abnormalities in the microscopic histology of the livers and spleens. In the stroma-free hemoglobin group the livers showed accumulation of hemoglobin in central veins and sinusoids, and hepatic steatosis. In conclusion, injected nano artificial red blood cells can be efficiently metabolized and removed by the reticuloendothelial system, and do not have any biochemical or histological adverse effects on the livers or the spleens. PMID:19043818
Wilhelm-Filho, Danilo; Fraga, César G; Boveris, Alberto
2017-09-01
Several oxidative stress markers and liver oxygen consumption were measured in different tissues of the marine fish Trichiurus lepturus in late summer and late winter, as well as in juveniles and adult females. Oxygen consumption in liver, superoxide dismutase (SOD) and catalase (CAT) activity in liver, red cells, lens and roe, vitamin E, ubiquinol 10 , β-carotene in liver, red cells, and roe, as well as contents of reduced glutathione (GSH) and lipoperoxidation (TBARS) in red cells were evaluated. Regarding ontogeny, compared to adult fish, juveniles showed significant higher SOD activity in liver and lens, as well as higher liver contents of vitamin E. In contrast, adult females showed higher contents of vitamin E in roe, ubiquinol 10 in liver and roe, and higher GSH levels in red cells, while the other markers remained unchanged. Regarding seasonal changes, no differences were detected in adult females for liver CAT and ubiquinol 10 , CAT in roe, vitamin E in roe and in red cells, liver and red cell ubiquinol 10 , and in GSH in red cells. However, and coinciding with the spawning period of late summer, liver oxygen consumption, SOD and CAT activity and ubiquinol 10 contents in roe and SOD activity in red cells, and red cell TBARS contents were higher compared to late winter. These temporal antioxidant adjustments of Trichiurus lepturus seem to be parallel to the higher oxygen consumption typical of juvenile forms and also to the intense spawning and foraging activities of adult females in late summer. Copyright © 2017. Published by Elsevier Inc.
Effect Of Leg Exercise On Vascular Volumes During Bed Rest
NASA Technical Reports Server (NTRS)
Greenleaf, J. E.; Vernikos, J.; Wade, C. E.; Barnes, P. R.
1993-01-01
Report describes experiments on effects of no-exercise regimen and of two leg-exercise regimens on volumes of plasma, volumes of red blood cells, densities of bodies, and water balances of 19 men (32 to 42 years old) confined to minus 6 degrees-head-down bed rest for 30 days. Purpose of study to determine whether either or both exercise regimens maintain plasma volume and to relate levels of hypovolemia to body fluid balances. Results showed during bed rest, plasma volume maintained in isotomic group but not in other two groups, and no significant differences in body densities, body weights, or water balances among three groups. Concludes isotonic-exercise regimen better than isokinetic-exercise regimen for maintaining plasma volume during prolonged exposure to bed rest.
Computational design of nanoparticle drug delivery systems for selective targeting
NASA Astrophysics Data System (ADS)
Duncan, Gregg A.; Bevan, Michael A.
2015-09-01
Ligand-functionalized nanoparticles capable of selectively binding to diseased versus healthy cell populations are attractive for improved efficacy of nanoparticle-based drug and gene therapies. However, nanoparticles functionalized with high affinity targeting ligands may lead to undesired off-target binding to healthy cells. In this work, Monte Carlo simulations were used to quantitatively determine net surface interactions, binding valency, and selectivity between targeted nanoparticles and cell surfaces. Dissociation constant, KD, and target membrane protein density, ρR, are explored over a range representative of healthy and cancerous cell surfaces. Our findings show highly selective binding to diseased cell surfaces can be achieved with multiple, weaker affinity targeting ligands that can be further optimized by varying the targeting ligand density, ρL. Using the approach developed in this work, nanomedicines can be optimally designed for exclusively targeting diseased cells and tissues.Ligand-functionalized nanoparticles capable of selectively binding to diseased versus healthy cell populations are attractive for improved efficacy of nanoparticle-based drug and gene therapies. However, nanoparticles functionalized with high affinity targeting ligands may lead to undesired off-target binding to healthy cells. In this work, Monte Carlo simulations were used to quantitatively determine net surface interactions, binding valency, and selectivity between targeted nanoparticles and cell surfaces. Dissociation constant, KD, and target membrane protein density, ρR, are explored over a range representative of healthy and cancerous cell surfaces. Our findings show highly selective binding to diseased cell surfaces can be achieved with multiple, weaker affinity targeting ligands that can be further optimized by varying the targeting ligand density, ρL. Using the approach developed in this work, nanomedicines can be optimally designed for exclusively targeting diseased cells and tissues. Electronic supplementary information (ESI) available: Movie showing simulation renderings of targeted (ρL = 1820/μm2, KD = 120 μM) nanoparticle selective binding to cancer (ρR = 256/μm2) vs. healthy (ρR = 64/μm2) cell surfaces. Target membrane proteins have linear color scale depending on binding energy ranging from white when unbound (URL = 0) to red when tightly bound (URL = UM). See DOI: 10.1039/c5nr03691g
Growth of northern hardwoods in New England: a 25-year update
William B. Leak; Jeffrey H. Gove
2008-01-01
Twenty-five-year results from a study of four stand density levels and three percentages of sawtimber in a beech-red maple-birch-hemlock stand in New Hampshire showed that moderate stand densities of 60- to 80-ft2/ac with 25- to 30-ft2 of sawtimber produced the best growth responses. Ingrowth was dominated by beech, red...
Relationships among red-cockaded woodpecker group density, nestling provisioning rates, and habitat
Richard N. Conner; D. Craig Rudolph; Richard R. Schaefer; Daniel Saenz; Clifford E. Shackelford
1999-01-01
We examined Red-cockaded Woodpecker (Picoides borealis) food provisioning rates of nestlings during the 1992 and 1993 breeding seasons on the Vernon Ranger District of the Kisatchie National Forest in Louisiana. Provisioning rates were monitored at nest trees in moderate (9.8 groups/2 km radius, n=10) and low (5.9 groups/2 km radius, n=10) density...
Hannemann, A; Rees, D C; Tewari, S; Gibson, J S
2015-11-01
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.
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.
Red Cell Indexes Made Easy Using an Interactive Animation: Do Students and Their Scores Concur?
ERIC Educational Resources Information Center
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…
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.
Madeira, S; Manteigas, A; Ribeiro, R; Otte, J; Fonseca, A Pina; Caetano, P; Abernethy, D; Boinas, F
2017-06-01
Bovine tuberculosis (bTB) is a worldwide zoonotic disease of domestic and wild animals. Eradication has proved elusive in those countries with intensive national programmes but with ongoing transmission between wildlife and cattle. In Portugal, a high-risk area for bTB was defined and specific measures implemented to assess and minimize the risk from wildlife. Data from the 2011 to 2014 hunting seasons for red deer (Cervus elaphus) and wild boar (Sus scrofa) were analysed with bovine demographic and bTB information to assess factors that determined the occurrence and distribution of bTB in both species. The likelihood of bTB-like lesions in wild boar was positively associated with density of red deer, wild boar and cattle, while for red deer, only their density and age were significant factors. The likelihood of Mycobacterium bovis isolation in wild boar was associated with density of cattle and red deer and also with the anatomical location of lesions, while for red deer, none of the variables tested were statistically significant. Our results suggest that, in the study area, the role of red deer and wild boar may be different from the one previously suggested by other authors for the Iberian Peninsula, as red deer may be the driving force behind M. bovis transmission to wild boar. These findings may assist the official services and game managing bodies for the management of hunting zones, what could also impact the success of the bTB eradication programme. © 2015 Blackwell Verlag GmbH.
The optical effect of a semiconductor laser on protecting wheat from UV-B radiation damage.
Qiu, Zong-Bo; Zhu, Xin-Jun; Li, Fang-Min; Liu, Xiao; Yue, Ming
2007-07-01
Lasers have been widely used in the field of biology along with the development of laser technology, but the mechanism of the bio-effect of lasers is not explicit. The objective of this paper was to test the optical effect of a laser on protecting wheat from UV-B damage. A patent instrument was employed to emit semiconductor laser (wavelength 650 nm) and incoherent red light, which was transformed from the semiconductor laser. The wavelength, power and lightfleck diameter of the incoherent red light are the same as those of the semiconductor laser. The semiconductor laser (wavelength 650 nm, power density 3.97 mW mm(-2)) and incoherent red light (wavelength 650 nm, power density 3.97 mW mm(-2)) directly irradiated the embryo of wheat seeds for 3 min respectively, and when the seedlings were 12-day-old they were irradiated by UV-B radiation (10.08 kJ m(-2)) for 12 h in the dark. Changes in the concentration of malondialdehyde (MDA), hydrogen peroxide (H(2)O(2)), glutathione (GSH), ascorbate (AsA), carotenoids (CAR), the production rate of superoxide radical (O(2)(-)), the activities of peroxidase (POD), catalase (CAT), superoxide dismutase (SOD) and the growth parameters of seedlings (plant height, leaf area and fresh weight) were measured to test the optical effect of the laser. The results showed that the incoherent red light treatment could not enhance the activities of SOD, POD and CAT and the concentration of AsA and CAR. When the plant cells were irradiated by UV-B, the incoherent red light treatment could not eliminate active oxygen and prevent lipid peroxidation in wheat. The results also clearly demonstrate that the plant DNA was damaged by UV-B radiation and semiconductor laser irradiance had the capability to protect plants from UV-B-induced DNA damage, while the incoherent red light could not. This is the first investigation reporting the optical effect of a semiconductor laser on protecting wheat from UV-B radiation damage.
Kim, Hyemin; Jang, Mirim; Kim, Yejin; Choi, Jiyea; Jeon, Jane; Kim, Jihoon; Hwang, Young-Il; Kang, Jae Seung; Lee, Wang Jae
2016-03-01
Because red ginseng and vitamin C have immunomodulatory function and anti-viral effect, we investigated whether red ginseng and vitamin C synergistically regulate immune cell function and suppress viral infection. Red ginseng and vitamin C were treated to human peripheral blood mononuclear cells (PBMCs) or sarcoma-associated herpesvirus (KSHV)-infected BCBL-1, and administrated to Gulo(-/-) mice, which are incapable of synthesizing vitamin C, with or without influenza A virus/H1N1 infection. Red ginseng and vitamin C increased the expression of CD25 and CD69 of PBMCs and natural killer (NK) cells. Co-treatment of them decreased cell viability and lytic gene expression in BCBL-1. In Gulo(-/-) mice, red ginseng and vitamin C increased the expression of NKp46, a natural cytotoxic receptor of NK cells and interferon (IFN)-γ production. Influenza infection decreased the survival rate, and increased inflammation and viral plaque accumulation in the lungs of vitamin C-depleted Gulo(-/-) mice, which were remarkably reduced by red ginseng and vitamin C supplementation. Administration of red ginseng and vitamin C enhanced the activation of immune cells like T and NK cells, and repressed the progress of viral lytic cycle. It also reduced lung inflammation caused by viral infection, which consequently increased the survival rate. © 2016 Royal Pharmaceutical Society, Journal of Pharmacy and Pharmacology.
Buoro, Sabrina; Vavassori, Mauro; Pipitone, Silvia; Benegiamo, Anna; Lochis, Eleonora; Fumagalli, Sabina; Falanga, Anna; Marchetti, Marina; Crippa, Alberto; Ottomano, Cosimo; Lippi, Giuseppe
2015-10-01
Current haematology analysers have variable sensitivity and accuracy for counting nucleated red blood cells in samples with low values and in all those conditions characterised by altered sensitivity of red blood cells to the lysing process, such as in beta-thalassaemia or sickle-cell diseases and in neonates. The aim of our study was to evaluate the performance of the automated analyser XE-2100 at counting nucleated red blood cells in the above-mentioned three categories of subjects with potentially altered red blood cell lysis sensitivity and yet a need for accurate nucleated red blood cell counts. We measured nucleated red blood cell count by XE-2100 in peripheral blood samples of 187 subjects comprising 55 patients with beta-thalassaemia (40 major and 15 traits), 26 sickle-cell patients, 56 neonates and 50 normal subject. Results were compared with those obtained by optical microscopy. Agreement between average values of the two methods was estimated by means of Pearson's correlation and bias analysis, whereas diagnostic accuracy was estimated by analysis of receiver operating characteristic curves. The comparison between the two methods showed a Pearson's correlation of 0.99 (95% CI; 0.98-0.99; p<0.001) and bias of -0.61 (95% CI, -1.5-0.3). The area under the curve of the nucleated red blood cell count in all samples was 0.98 (95% CI, 0.96-1.00; p<0.001). Sub-analysis revealed an area under curve of 0.99 (95% CI, 0.98-1.00; p<0.001) for patients with thalassaemia, 0.94 (95% CI, 0.85-1.00; p<0.001) for patients with sickle cell anaemia, and 1.00 (95% CI, 1.0-1.0) for neonates. XE-2100 has excellent performance for nucleated red blood cell counting, especially in critical populations such as patients with haemoglobinopathies and neonates.
Previous cryopreservation alters the natural history of the red blood cell storage lesion
Chang, Alex L.; Hoehn, Richard S.; Jernigan, Peter; Cox, Daniel; Schreiber, Martin; Pritts, Timothy A.
2016-01-01
Background During storage, packed red blood cells (pRBCs) undergo a number of biochemical, metabolic and morphologic changes, collectively known as the “storage lesion”. We aimed to determine the effect of cryopreservation on the red blood cell storage lesion compared to traditional 4°C storage. Methods Previously cryopreserved human packed red blood cells were compared to age matched never frozen packed red blood cells obtained from the local blood bank. The development of the red cell storage lesion was evaluated after 7, 14, 21, 28, and 42 days of storage at 4°C in AS-3 storage medium. We measured physiological parameters including cell counts, lactic acid and potassium concentrations as well as signs of eryptosis including loss of phosphatidylserine (PS) asymmetry, microparticle production and osmotic fragility in hypotonic saline. Results Compared to controls, previously cryopreserved pRBC at 7 days of storage in AS-3 showed lower red cell counts (3.7 vs 5.3 ×10^6 cells/uL, p(<0.01), hemoglobin (12.0 vs 16.5 g/dL, p<0.01), hematocrit (33.0 vs 46.5%, p<0.01), and pH (6.27 vs 6.72, p<0.01). Over 28 days of storage, storage cryopreserved pRBC developed increased cell free hemoglobin (0.7 vs 0.3 g/dL, p<0.01), greater PS exposure (10.1 vs 3.3%, p<0.01), and microparticle production (30,836 vs 1,802 MP/uL, p<0.01). Previously cryopreserved cells were also less resistant to osmotic stress. Conclusion The red blood cell storage lesion is accelerated in previously cryopreserved pRBC after thawing. Biochemical deterioration of thawed and deglycerolized red cells suggests that storage time prior to transfusion should be limited in order to achieve similar risk profiles as never frozen standard liquid storage pRBC units. PMID:27380532
Hou, Bin; Hu, Yongyou; Sun, Jian
2012-05-01
To study the effect of cathode type on performance and microbial diversity of the MFC, aerobic biocathode and air-cathode were incorporated into microbial fuel cells (MFCs) which were explored for simultaneous azo dye decolorization and electricity generation. The electrochemical impedance spectroscopy (EIS) results demonstrated that the catalytic activity of the microorganisms on the biocathode surface was comparable with that of the platinum coated on the air-cathode. The power density achieved by using biocathode was lower than air-cathode, but the biocathode could greatly improve the Congo red decolorization rate. By using the biocathode, 96.4% decolorization of Congo red was obtained within 29 h, whereas, about 107 h was required to achieve the same decolorization efficiency with the air-cathode. 16S rRNA sequencing analysis demonstrated a phylogenetic diversity in the communities of the anode biofilm and showed clear differences between the anode-attached populations in the MFCs with a different cathode type. Copyright © 2012 Elsevier Ltd. All rights reserved.
Goonoo, Nowsheen; Khanbabaee, Behnam; Steuber, Marc; Bhaw-Luximon, Archana; Jonas, Ulrich; Pietsch, Ullrich; Jhurry, Dhanjay; Schönherr, Holger
2017-05-08
Novel electrospun materials for bone tissue engineering were obtained by blending biodegradable polyhydroxybutyrate (PHB) or polyhydroxybutyrate valerate (PHBV) with the anionic sulfated polysaccharide κ-carrageenan (κ-CG) in varying ratios. In both systems, the two components phase separated as shown by FTIR, DSC and TGA. According to the contact angle data, κ-CG was localized preferentially at the fiber surface in PHBV/κ-CG blends in contrast to PHB/κ-CG, where the biopolymer was mostly found within the fiber. In contrast to the neat polyester fibers, the blends led to the formation of much smaller apatite crystals (800 nm vs 7 μm). According to the MTT assay, NIH3T3 cells grew in higher density on the blend mats in comparison to neat polyester mats. The osteogenic differentiation potential of the fibers was determined by SaOS-2 cell culture for 2 weeks. Alizarin red-S staining suggested an improved mineralization on the blend fibers. Thus, PHBV/κ-CG fibers resulted in more pronounced bioactive and osteogenic properties, including fast apatite-forming ability and deposition of nanosized apatite crystals.
Del Bó, Cristian; Simonetti, Paolo; Gardana, Claudio; Riso, Patrizia; Lucchini, Giorgio; Ciappellano, Salvatore
2013-03-01
This study investigated the effect of moderate consumption of horse meat on iron status, lipid profile and fatty acid composition of red blood cells in healthy male volunteers. Fifty-two subjects were randomly assigned to two groups of 26 subjects each: a test group consuming two portions of 175 g/week of horse meat, and a control group that abstained from eating horse meat during the 90 days trial. Before and after 90 days, blood samples were collected for analysis. Horse meat consumption significantly (p ≤ 0.05) reduced serum levels of total and low-density lipoprotein cholesterol ( - 6.2% and - 9.1%, respectively) and transferrin ( - 4.6%). Total n - 3, long chain polyunsaturated fatty acids n - 3 and docosahexeanoic acid content in erythrocytes increased (p ≤ 0.05) by about 7.8%, 8% and 11%, respectively. In conclusion, the regular consumption of horse meat may contribute to the dietary intake of n - 3 polyunsaturated fatty acids and may improve lipid profile and iron status in healthy subjects.
Infra-red photoresponse of mesoscopic NiO-based solar cells sensitized with PbS quantum dot
Raissi, Mahfoudh; Pellegrin, Yann; Jobic, Stéphane; Boujtita, Mohammed; Odobel, Fabrice
2016-01-01
Sensitized NiO based photocathode is a new field of investigation with increasing scientific interest in relation with the development of tandem dye-sensitized solar cells (photovoltaic) and dye-sensitized photoelectrosynthetic cells (solar fuel). We demonstrate herein that PbS quantum dots (QDs) represent promising inorganic sensitizers for NiO-based quantum dot-sensitized solar cells (QDSSCs). The solar cell sensitized with PbS quantum dot exhibits significantly higher photoconversion efficiency than solar cells sensitized with a classical and efficient molecular sensitizer (P1 dye = 4-(Bis-{4-[5-(2,2-dicyano-vinyl)-thiophene-2-yl]-phenyl}-amino)-benzoic acid). Furthermore, the system features an IPCE (Incident Photon-to-Current Efficiency) spectrum that spreads into the infra-red region, reaching operating wavelengths of 950 nm. The QDSSC photoelectrochemical device works with the complexes tris(4,4′-ditert-butyl-2,2′-bipyridine)cobalt(III/II) redox mediators, underscoring the formation of a long-lived charge-separated state. The electrochemical impedance spectrocopy measurements are consistent with a high packing of the QDs upon the NiO surface, the high density of which limits the access of the electrolyte and results in favorable light absorption cross-sections and a significant hole lifetime. These notable results highlight the potential of NiO-based photocathodes sensitized with quantum dots for accessing and exploiting the low-energy part of the solar spectrum in photovoltaic and photocatalysis applications. PMID:27125454
... blood. About Sickle Cell Disease Sickle cell disease is a common, inherited red blood disorder. Throughout their lives, sickle cell disease patients ... more time, consider a Power Red donation . Power Red is similar to a whole blood donation, except a special machine is used to ...
Sophocleous, Reece A; Mullany, Phillip R F; Winter, Kelly M; Marks, Denese C; Sluyter, Ronald
2015-08-01
Phosphatidylserine (PS) exposure facilitates the removal of red blood cells (RBCs) from the circulation, potentially contributing to the loss of stored RBCs after transfusion, as well as senescent RBCs. Activation of the P2X7 receptor by extracellular adenosine 5'-triphosphate (ATP) can induce PS exposure on freshly isolated human RBCs, but whether this process occurs in stored RBCs or changes during RBC aging is unknown. RBCs were processed and stored according to Australian blood banking guidelines. PS exposure was determined by annexin V binding and flow cytometry. Efficacy of P2X antagonists was assessed by flow cytometric measurements of ATP-induced ethidium+ uptake in RPMI 8226 cells. Osmotic fragility was assessed by lysis in hypotonic saline. RBCs were fractionated by discontinuous density centrifugation. ATP (1 mmol/L) induced PS exposure on RBCs stored for less than 1 week. This process was near-completely inhibited by the P2X7 antagonists A438079 and AZ10606120 and the P2X1/P2X7 antagonist MRS2159 but not the P2X1 antagonist NF499. ATP-induced PS exposure on RBCs was not dependent on K+, Na+, or Cl- fluxes. ATP did not alter the osmotic fragility of stored RBCs. ATP-induced PS exposure was similar between RBCs of different densities. ATP-induced PS exposure was also similar between RBCs stored for less than 1 week or for 6 weeks. The propensity of RBCs to undergo P2X7-mediated PS exposure does not alter during in vivo and ex vivo aging. Thus, P2X7 activation is unlikely to be involved in the removal of senescent RBCs or stored RBCs after transfusion. © 2015 AABB.
21 CFR 640.15 - Segments for testing.
Code of Federal Regulations, 2014 CFR
2014-04-01
... cells. (c) All segments accompanying a unit of Red Blood Cells shall be filled at the time the blood is... ADDITIONAL STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Red Blood Cells § 640.15 Segments for testing... provided with each unit of Whole Blood or Red Blood Cells when issued or reissued. (b) Before they are...
21 CFR 660.36 - Samples and protocols.
Code of Federal Regulations, 2014 CFR
2014-04-01
..., whenever a new donor is used, a sample of red blood cells from each new donor used in a cell panel intended... ADDITIONAL STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Reagent Red Blood Cells § 660.36 Samples... distribution of each lot of Reagent Red Blood Cells for detection or identification of unexpected antibodies...
21 CFR 660.36 - Samples and protocols.
Code of Federal Regulations, 2013 CFR
2013-04-01
..., whenever a new donor is used, a sample of red blood cells from each new donor used in a cell panel intended... ADDITIONAL STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Reagent Red Blood Cells § 660.36 Samples... distribution of each lot of Reagent Red Blood Cells for detection or identification of unexpected antibodies...
21 CFR 640.15 - Segments for testing.
Code of Federal Regulations, 2011 CFR
2011-04-01
... cells. (c) All segments accompanying a unit of Red Blood Cells shall be filled at the time the blood is... ADDITIONAL STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Red Blood Cells § 640.15 Segments for testing... provided with each unit of Whole Blood or Red Blood Cells when issued or reissued. (b) Before they are...
21 CFR 660.36 - Samples and protocols.
Code of Federal Regulations, 2012 CFR
2012-04-01
..., whenever a new donor is used, a sample of red blood cells from each new donor used in a cell panel intended... ADDITIONAL STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Reagent Red Blood Cells § 660.36 Samples... distribution of each lot of Reagent Red Blood Cells for detection or identification of unexpected antibodies...
21 CFR 640.15 - Segments for testing.
Code of Federal Regulations, 2013 CFR
2013-04-01
... cells. (c) All segments accompanying a unit of Red Blood Cells shall be filled at the time the blood is... ADDITIONAL STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Red Blood Cells § 640.15 Segments for testing... provided with each unit of Whole Blood or Red Blood Cells when issued or reissued. (b) Before they are...
21 CFR 640.15 - Segments for testing.
Code of Federal Regulations, 2012 CFR
2012-04-01
... cells. (c) All segments accompanying a unit of Red Blood Cells shall be filled at the time the blood is... ADDITIONAL STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Red Blood Cells § 640.15 Segments for testing... provided with each unit of Whole Blood or Red Blood Cells when issued or reissued. (b) Before they are...
21 CFR 640.15 - Segments for testing.
Code of Federal Regulations, 2010 CFR
2010-04-01
... ADDITIONAL STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Red Blood Cells § 640.15 Segments for testing... provided with each unit of Whole Blood or Red Blood Cells when issued or reissued. (b) Before they are... cells. (c) All segments accompanying a unit of Red Blood Cells shall be filled at the time the blood is...
Moderate red wine consumption and cardiovascular disease risk: beyond the "French paradox".
Lippi, Giuseppe; Franchini, Massimo; Favaloro, Emmanuel J; Targher, Giovanni
2010-02-01
The term FRENCH PARADOX was coined in 1992 to describe the relatively low incidence of cardiovascular disease in the French population, despite a relatively high dietary intake of saturated fats, and potentially attributable to the consumption of red wine. After nearly 20 years, several studies have investigated the fascinating, overwhelmingly positive biological and clinical associations of red wine consumption with cardiovascular disease and mortality. Light to moderate intake of red wine produces a kaleidoscope of potentially beneficial effects that target all phases of the atherosclerotic process, from atherogenesis (early plaque development and growth) to vessel occlusion (flow-mediated dilatation, thrombosis). Such beneficial effects involve cellular signaling mechanisms, interactions at the genomic level, and biochemical modifications of cellular and plasma components. Red wine components, especially alcohol, resveratrol, and other polyphenolic compounds, may decrease oxidative stress, enhance cholesterol efflux from vessel walls (mainly by increasing levels of high-density lipoprotein cholesterol), and inhibit lipoproteins oxidation, macrophage cholesterol accumulation, and foam-cell formation. These components may also increase nitric oxide bioavailability, thereby antagonizing the development of endothelial dysfunction, decrease blood viscosity, improve insulin sensitivity, counteract platelet hyperactivity, inhibit platelet adhesion to fibrinogen-coated surfaces, and decrease plasma levels of von Willebrand factor, fibrinogen, and coagulation factor VII. Light to moderate red wine consumption is also associated with a favorable genetic modulation of fibrinolytic proteins, ultimately increasing the surface-localized endothelial cell fibrinolysis. Overall, therefore, the "French paradox" may have its basis within a milieu containing several key molecules, so that favorable cardiovascular benefits might be primarily attributable to combined, additive, or perhaps synergistic effects of alcohol and other wine components on atherogenesis, coagulation, and fibrinolysis. Conversely, chronic heavy alcohol consumption and binge drinking are associated with increased risk of cardiovascular events. In conclusion, although mounting evidence strongly supports beneficial cardiovascular effects of moderate red wine consumption (one to two drinks per day; 10-30 g alcohol) in most populations, clinical advice to abstainers to initiate daily alcohol consumption has not yet been substantiated in the literature and must be considered with caution on an individual basis.
Panch, Sandhya R.; Yau, Yu Ying; Kang, Elizabeth M.; De Ravin, Suk See; Malech, Harry L.; Leitman, Susan F.
2014-01-01
Background G-CSF mobilized autologous hematopoietic progenitor cells (HPC) may be collected by apheresis of patients with chronic granulomatous disease (CGD) and severe combined immunodeficiency (SCID) for use in gene therapy trials. CD34+ cell mobilization has not been well characterized in such patients. Study Design and Methods We retrospectively evaluated CD34+ cell mobilization and collection in 73 consecutive CGD and SCID patients and in 99 age, weight and G-CSF dose-matched healthy allogeneic controls. Results In subjects aged ≤20 years, day 5 pre-apheresis circulating CD34+ counts were significantly lower in CGD and SCID than in controls; mean peak CD34+ cells 58, 64, and 87/uL, respectively, p=0.01. The SCIDs had lower CD34+ collection efficiency than CGDs and controls; mean efficiency 40%, 63% and 57%, respectively, p=0.003. In subjects >20 years, the CGDs had significantly lower CD34+ cell mobilization than controls; mean peak CD34+ cells 41 and 113/uL, respectively, p<0.0001. In a multivariate analysis, lower sedimentation rate (ESR) at mobilization was significantly correlated with better CD34+ cell mobilization, p=0.007. In SCIDs, CD34 collection efficiency was positively correlated with higher red cell indices (MCV: R2=0.77; MCH: R2=0.94; MCHC: R2=0.7, p<0.007) but not hemoglobin. Conclusions CGD and SCID populations are characterized by significantly less robust CD34+ HPC mobilization than healthy controls. The presence of active inflammation/infection as suggested by an elevated ESR may negatively impact mobilization. Among SCIDs, markedly reduced CD34 collection efficiencies were related to iron deficiency, wherein decreased red cell size and density may impair apheresis cell separation mechanics. PMID:25143186
NASA Astrophysics Data System (ADS)
Roy, Ronald A.
2004-05-01
Robert Apfel believed in the creative application of acoustics technology to difficult problems in biomedical sensing. Much of his work in this area focused on material characterization, with the intention of effecting diagnosis. His early work in blood cell characterization employed acoustic levitation to measure the bulk mechanical properties of human red blood cells. This subsequently paved the way to the use of high-frequency acoustic scattering to yield the compressibility and density of individual blood cells. Technology developed in this later effort was then adapted to the very difficult problem of transient micro-cavitation detection, and the active cavitation detector (ACD) was born. This paper traces this line of work from its origins and, in the process, serves to celebrate Bob Apfel's peerless ingenuity and irrepressible creativity.
... the red blood cells. Most of the hemoglobin is found inside the red blood cells, not in the serum. Hemoglobin carries oxygen ... Hemoglobin (Hb) is the main component of red blood cells. It is a ... oxygen. This test is done to diagnose or monitor how severe ...
Research opportunities in loss of red blood cell mass in space flight
NASA Technical Reports Server (NTRS)
Talbot, J. M.; Fisher, K. D.
1985-01-01
Decreases of red blood cell mass and plasma volume have been observed consistently following manned space flights. Losses of red cell mass by United States astronauts have averaged 10 to 15% (range: 2 to 21%). Based on postflight estimates of total hemoglobin, Soviet cosmonauts engaged in space missions lasting from 1 to 7 months have exhibited somewhat greater losses. Restoration of red cell mass requires from 4 to 6 weeks following return to Earth, regardless of the duration of space flight.
Nie, Yudong; Zhang, Zhi; Shen, Qian; Gao, Wenjin; Li, Yingfan
2016-05-18
The Three Gorges Dam is one of the largest hydroelectric power plants worldwide; its reservoir was preliminarily impounded in 2003 and finally impounded to 175 m in 2012. The impoundment caused some environmental problems, such as algal blooms. Carbonic anhydrase (CA) is an important biocatalyst in the carbon utilization by algae and plays an important role in algal blooms. CA has received considerable attention for its role in red tides in oceans, but less investigation has been focused on its role in algal blooms in fresh water. In this study, the seasonal variation of water quality parameters, different carbon forms, carbonic anhydrase activity (CAA), and the algal cell density of four sampling sites in the urban section of the Jialing River were investigated from November 1, 2013 to October 31, 2014. Results indicated that CAA exhibited a positive correlation with dissoluble organic carbon (DOC), pH, and temperature, but a negative correlation with CO2 and dissoluble inorganic carbon (DIC). Algal cell density exhibited a positive correlation with flow velocity (V), pH, particulate organic carbon (POC), and CAA, a negative correlation with CO2, and a negative partial correlation with DIC. The relationship between CAA and algal cell density for the entire year can be described as cells = 23.278CAA - 42.666POC + 139.547pH - 1057.106. The algal bloom prediction model for the key control period can be described as cells = -45.895CAA + 776.103V- 29.523DOC + 14.219PIC + 35.060POC + 19.181 (2 weeks in advance) and cells = 69.200CAA + 203.213V + 4.184CO2 + 38.911DOC + 40.770POC - 189.567 (4 weeks in advance). The findings in this study demonstrate that the carbon utilization by algae is conducted by CA and provide a new method of monitoring algal cell density and predicting algal blooms.
A mathematical and experimental simulation of the hematological response to weightlessness
NASA Technical Reports Server (NTRS)
Kimzey, S. L.; Leonard, J. I.; Johnson, P. C.
1979-01-01
A mathematical model of erythropoiesis control was used to simulate the effects of bedrest and zero-g on the circulating red cell mass. The model incorporates the best current understanding of the dynamics of red cell production and destruction and the associated feedback regulation. Specifically studied were the hemodynamic responses of a 28-day bedrest study devised to simulate Skylab experience. The results support the hypothesis that red cell loss during supine bedrest is a normal physiological feedback process in response to hemoconcentration enhanced tissue oxygenation and suppression of red cell production. Model simulation suggested the possibilities that this period was marked by some combination of increased oxygen-hemoglobin affinity, small reduction in mean red cell life span, ineffective erythropoiesis, or abnormal reticulocytosis.
Overstory density affects field performance of underplanted red oak (Quercus rubra L.) in Ontario
Daniel C. Dey; William C. Parker
1997-01-01
Red oak seedlings were underplanted in a closed-canopy mature northern hardwood stand and an adjacent shelterwood in central Ontario. Overstory density effects on seedling survival and growth were assessed 2 yr after planting. After 2 yr, seedling survival was 90% in the uncut stand and over 99% in the shelterwood. Seedlings in the uncut stand experienced negligible or...
Bio-inspired Cryo-ink Preserves Red Blood Cell Phenotype and Function during Nanoliter Vitrification
Assal, Rami El; Guven, Sinan; Gurkan, Umut Atakan; Gozen, Irep; Shafiee, Hadi; Dalbeyber, Sedef; Abdalla, Noor; Thomas, Gawain; Fuld, Wendy; Illigens, Ben M.W.; Estanislau, Jessica; Khoory, Joseph; Kaufman, Richard; Zylberberg, Claudia; Lindeman, Neal; Wen, Qi; Ghiran, Ionita; Demirci, Utkan
2014-01-01
Current red blood cell cryopreservation methods utilize bulk volumes, causing cryo-injury of cells, which results in irreversible disruption of cell morphology, mechanics, and function. An innovative approach to preserve human red blood cell morphology, mechanics, and function following vitrification in nanoliter volumes is developed using a novel cryo-ink integrated with a bio-printing approach. PMID:25047246
Mahapatra, Ajit Kumar; Maji, Rajkishor; Maiti, Kalipada; Adhikari, Susanta Sekhar; Das Mukhopadhyay, Chitrangada; Mandal, Debasish
2014-01-07
A new BODIPY-azaindole based fluorescent sensor 1 was designed and synthesized as a new colorimetric and ratiometric fluorescent chemosensor for fluoride. The binding and sensing abilities of sensor 1 towards various anions were studied by absorption, emission and (1)H NMR titration spectroscopies. The spectral responses of 1 to fluoride in acetonitrile-water were studied: an approximately 69 nm red shift in absorption and ratiometric fluorescent response was observed. The striking light yellow to deep brown color change in ambient light and green to blue emission color change are thought to be due to the deprotonation of the indole moiety of the azaindole fluorophore. From the changes in the absorption, fluorescence, and (1)H NMR titration spectra, proton-transfer mechanisms were deduced. Density function theory and time-dependent density function theory calculations were conducted to rationalize the optical response of the sensor. Results were supported by confocal fluorescence imaging and MTT assay of live cells.
Association of white cell and red cell antibodies in human sera
Ross, Jill M.; James, D. C. O.
1973-01-01
Five hundred and eighteen human sera containing known red cell antibodies were tested for lymphocytotoxic antibodies and 81 sera were found to contain them. Thirty-nine antibodies were fully characterized. The frequencies of anti-I, K, Vw, and Wra were significantly greater in those of the 518 sera which also contained white cell antibodies. Four hundred and ninety-four of the 518 sera containing red cell antibodies contained anti-Rh and anti-Kell. The frequency of white cell antibodies in this group was 15% compared with a frequency of 12% in a series of 923 antenatal samples not containing anti-Rh or anti-Kell. The frequencies of different anti-HL-A specificities were compared in the two groups with or without anti-Rh and anti-Kell antibodies. Anti-HL-A 1, 7, and 8 occurred more frequently in the absence of these red cell antibodies and anti-HL-A 12 occurred more frequently in their presence. No correlation was found between particular red cell and white cell antibodies. PMID:4197543
Salehpour, Farzad; Rasta, Seyed Hossein; Mohaddes, Gisou; Sadigh-Eteghad, Saeed; Salarirad, Sima
2016-09-01
The application of transcranial low-level light/laser therapy (tLLLT) in the range of red to near-infrared (NIR) spectrum for psychological disorders is a new area that is attracting growing interest in recent years. The photomodulation effects of NIR and red coherent lights on the activity of cytochrome c oxidase in neuronal cells of brain have been recently introduced. This study, therefore, sought to compare the therapeutic effects of 10-Hz pulsed wave NIR (810 nm) laser with red (630 nm) laser using the same delivered energy density and Citalopram in rat chronic mild stress (CMS) model of depression and anxiety. CMS procedures (for 4 weeks) were used to induce stress. GaAlAs diode laser with red and NIR wavelengths on 10-Hz pulsed wave (50% duty cycle) were used to perform tLLLT treatment for three weeks. An energy density of about 1.2 J/cm-(2) per each session was delivered through a light spot with a diameter of 3-mm to the prefrontal cortex for both wavelengths. Citalopram (10 mg/kg, Intraperitoneal) was administered for twenty-one consecutive days to the drug group. The findings of the present study showed an increase in swimming and decrease in immobility time, for both NIR laser and Citalopram groups compared to the stress group in forced swimming test. Anxiety-like behaviors showed insignificant decrease in all treatment groups in elevated plus maze test. The induction of stress significantly increased serum cortisol levels and treatments with both red laser and Citalopram decreased it. Hyperglycemia induced by CMS returned to normal levels in all treatment groups. The assessment of body weight also showed a significant increase in NIR laser group compared to the stress group by the end of the experiment. This study showed that non-invasive tLLLT using 10-Hz pulsed NIR laser light was as effective as Citalopram and more effective than red laser in the treatment of depressive-like behaviors and may help improve tLLLT as an alternative non-pharmacological treatments of psychological disorders such as depression. Lasers Surg. Med. 48:695-705, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.
Hannemann, A.; Rees, D.C.; Tewari, S.; Gibson, J.S.
2015-01-01
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. PMID:26870793
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.
The morphological classification of normal and abnormal red blood cell using Self Organizing Map
NASA Astrophysics Data System (ADS)
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.
NASA Technical Reports Server (NTRS)
Kimzey, S. L.; Burns, L. C.; Fischer, C. L.
1974-01-01
The significance of the transformations in red cell shape observed during the Skylab study must be considered relative to the limitation of man's participation in extended space flight missions. The results of this one study are not conclusive with respect to this question. Based on these examinations of red cells in normal, healthy men and based on other Skylab experiment data relative to the functional capacity of the red cells in vitro and the performance capacity of man as an integrated system, the changes observed would not appear to be the limiting factor in determining man's stay in space. However, the results of this experiment and the documented red cell mass loss during space flight raise serious questions at this time relative to the selection criteria utilized for passengers and crews of future space flights. Until the specific cause and impact of the red cell shape change on cell survival in vivo can be resolved, individuals with diagnosed hematologic abnormalities should not be considered as prime candidates for missions, especially those of longer duration.
Chen, C S; Martin, O C; Pagano, R E
1997-01-01
N-[5-(5, 7-dimethyl Bodipy)-1-pentanoyl]-D-erythro-sphingosylphosphorylcholine (C5-DMB-SM), a fluorescent analog of sphingomyelin, has been used in a study of the formation of very early endosomes in human skin fibroblasts. This lipid exhibits a shift in its fluorescence emission maximum from green (approximately 515 nm) to red (approximately 620 nm) wavelengths with increasing concentrations in membranes. When cells were incubated with 5 microM C5-DMB-SM at 4 degrees C and washed, only plasma membrane fluorescence (yellow-green) was observed. When these cells were briefly (< or = 1 min) warmed to 37 degrees C to allow internalization to occur, and then incubated with defatted bovine serum albumin (back-exchanged) at 11 degrees C to remove fluorescent lipids from the plasma membrane, C5-DMB-SM was distributed in a punctate pattern throughout the cytoplasm. Interestingly, within the same cell some endosomes exhibited green fluorescence, whereas others emitted red-orange fluorescence. Furthermore, the red-orange endosomes were usually seen at the periphery of the cell, while the green endosomes were more uniformly distributed throughout the cytoplasm. This mixed population of endosomes was seen after internalization times as short as 7 s and was also seen over a wide range of C5-DMB-SM concentrations (1-25 microM). Control experiments established that the variously colored endosomes were not induced by changes in pH, membrane potential, vesicle size, or temperature. Quantitative fluorescence microscopy demonstrated that the apparent concentration of the lipid analog in the red-orange endosomes was severalfold higher than its initial concentration at the plasma membrane, suggesting selective internalization (sorting) of the lipid into a subset of early endosomes. Colocalization studies using C5-DMB-SM and either anti-transferrin receptor antibodies or fluorescently labeled low-density lipoprotein further demonstrated that this subpopulation of endosomes resulted from receptor-mediated endocytosis. We conclude that the spectral properties of C5-DMB-SM can be used to distinguish unique populations of early endosomes from one another and to record dynamic changes in their number and distribution within living cells. Images FIGURE 1 FIGURE 3 FIGURE 4 FIGURE 6 FIGURE 8 FIGURE 9 PMID:8994591
Role of Rab5 in the formation of macrophage-derived foam cell.
Chan, Lokwern; Hong, Jin; Pan, Junjie; Li, Jian; Wen, Zhichao; Shi, Haiming; Ding, Jianping; Luo, Xinping
2017-09-12
Foam cells play a key role in the occurrence and pathogenesis of atherosclerosis. Its formation starts with the ingestion of oxidized low-density lipoprotein (oxLDL). The process is associated with Ras related protein in brain 5 (Rab5) which plays a critical role in regulating endocytosis and early endosomal trafficking. Base on this, we presumed that Rab5 might participate in the maturation of foam cell. The aim of this study is to investigate the effect of Rab5 on macrophage cholesterol during the evolvement of macrophage when induced by oxLDL to the formation of foam cell. Immunohistochemistry was performed to analyze the distribution of macrophages and Rab5 in atherosclerotic plaque. RNA inteference study and transfection of inactive mutant (GFP-Rab5-S34N) and active mutant (GFP-Rab5-Q79L) in U937-derived macrophage were utilized to investigate the impact of Rab5 on the process of macrophage cholesterol, which could be detected by oil red O staining, determination of intracellular lipid content, filipin staining, nile red staining and the costaining of early endosome antigen-1 (EEA-1) and 1,1'-dioctadecyl-3,3,3',3'-tetramethylin dicarbocyanine (Dil)-labelled oxLDL (Dil-oxLDL). Rab5 was found abundantly localized in macrophage rich areas of human atherosclerotic lesions. On the foam cell study, the expression of Rab5 was increased after the incubation of oxLDL. The inteference study indicated the depletion of Rab5 led to the decreases of oil red O staining areas, total cholesterol and cholesterol esters in U937-derived marophages. Moreover, the fluorescence intensity of filipin and nile red staining were lower in GFP-Rab5-S34N as compared with GFP-Rab5-Q79L. The confocal study demonstrated less Dil-oxLDL was internalized in GFP-Rab5-S34N as compared with GFP-Rab5-Q79L; the result showed also the decrease in colocalization of internalized Dil-oxLDL and EEA-1 for GFP-Rab5-S34N as compared with GFP-Rab5-Q79L. Rab5 plays an important role in modulating the intracellular cholesterol of macrophages and consequently mediating the formation of foam cells.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Park, Jun Hyuk; Lee, Jong Won; Kim, Dong Yeong
The temperature-dependent external quantum efficiencies (EQEs) were investigated for a 620 nm AlGaInP red light-emitting diodes (LEDs), a 450 nm GaInN blue LED, and a 285 nm AlGaN deep-ultraviolet (DUV) LED. We observed distinct differences in the variation of the EQE with temperature and current density for the three types of LEDs. Whereas the EQE of the AlGaInP red LED increases as temperature decreases below room temperature, the EQEs of GaInN blue and AlGaN DUV LEDs decrease for the same change in temperature in a low-current density regime. The free carrier concentration, as determined from the dopant ionization energy, shows a strong material-system-specificmore » dependence, leading to different degrees of asymmetry in carrier concentration for the three types of LEDs. We attribute the EQE variation of the red, blue, and DUV LEDs to the different degrees of asymmetry in carrier concentration, which can be exacerbated at cryogenic temperatures. As for the EQE variation with temperature in a high-current density regime, the efficiency droop for the AlGaInP red and GaInN blue LEDs becomes more apparent as temperature decreases, due to the deterioration of the asymmetry in carrier concentration. However, the EQE of the AlGaN DUV LED initially decreases, then reaches an EQE minimum point, and then increases again due to the field-ionization of acceptors by the Poole-Frenkel effect. The results elucidate that carrier transport phenomena allow for the understanding of the droop phenomenon across different material systems, temperatures, and current densities.« less
Group quenching and galactic conformity at low redshift
NASA Astrophysics Data System (ADS)
Treyer, M.; Kraljic, K.; Arnouts, S.; de la Torre, S.; Pichon, C.; Dubois, Y.; Vibert, D.; Milliard, B.; Laigle, C.; Seibert, M.; Brown, M. J. I.; Grootes, M. W.; Wright, A. H.; Liske, J.; Lara-Lopez, M. A.; Bland-Hawthorn, J.
2018-06-01
We quantify the quenching impact of the group environment using the spectroscopic survey Galaxy and Mass Assembly to z ˜ 0.2. The fraction of red (quiescent) galaxies, whether in groups or isolated, increases with both stellar mass and large-scale (5 Mpc) density. At fixed stellar mass, the red fraction is on average higher for satellites of red centrals than of blue (star-forming) centrals, a galactic conformity effect that increases with density. Most of the signal originates from groups that have the highest stellar mass, reside in the densest environments, and have massive, red only centrals. Assuming a colour-dependent halo-to-stellar-mass ratio, whereby red central galaxies inhabit significantly more massive haloes than blue ones of the same stellar mass, two regimes emerge more distinctly: at log (Mhalo/M⊙) ≲ 13, central quenching is still ongoing, conformity is no longer existent, and satellites and group centrals exhibit the same quenching excess over field galaxies at all mass and density, in agreement with the concept of `group quenching'; at log (Mh/M⊙) ≳ 13, a cut-off that sets apart massive (log (M⋆/M⊙) > 11), fully quenched group centrals, conformity is meaningless, and satellites undergo significantly more quenching than their counterparts in smaller haloes. The latter effect strongly increases with density, giving rise to the density-dependent conformity signal when both regimes are mixed. The star formation of blue satellites in massive haloes is also suppressed compared to blue field galaxies, while blue group centrals and the majority of blue satellites, which reside in low-mass haloes, show no deviation from the colour-stellar mass relation of blue field galaxies.
[Primary culture of human normal epithelial cells].
Tang, Yu; Xu, Wenji; Guo, Wanbei; Xie, Ming; Fang, Huilong; Chen, Chen; Zhou, Jun
2017-11-28
The traditional primary culture methods of human normal epithelial cells have disadvantages of low activity of cultured cells, the low cultivated rate and complicated operation. To solve these problems, researchers made many studies on culture process of human normal primary epithelial cell. In this paper, we mainly introduce some methods used in separation and purification of human normal epithelial cells, such as tissue separation method, enzyme digestion separation method, mechanical brushing method, red blood cell lysis method, percoll layered medium density gradient separation method. We also review some methods used in the culture and subculture, including serum-free medium combined with low mass fraction serum culture method, mouse tail collagen coating method, and glass culture bottle combined with plastic culture dish culture method. The biological characteristics of human normal epithelial cells, the methods of immunocytochemical staining, trypan blue exclusion are described. Moreover, the factors affecting the aseptic operation, the conditions of the extracellular environment, the conditions of the extracellular environment during culture, the number of differential adhesion, and the selection and dosage of additives are summarized.
The use of enzymopathic human red cells in the study of malarial parasite glucose metabolism.
Roth, E; Joulin, V; Miwa, S; Yoshida, A; Akatsuka, J; Cohen-Solal, M; Rosa, R
1988-05-01
The in vitro growth of Plasmodium falciparum malaria parasites was assayed in mutant red cells deficient in either diphosphoglycerate mutase (DPGM) or phosphoglycerate kinase (PGK). In addition, cDNA probes developed for human DNA sequences coding for these enzymes were used to examine the parasite genome by means of restriction endonuclease digestion and Southern blot analysis of parasite DNA. In both types of enzymopathic red cells, parasite growth was normal. In infected DPGM deficient red cells, no DPGM activity could be detected, and in normal red cells, DPGM activity declined slightly in a manner suggestive of parasite catabolism of host protein. However, in infected PGK deficient red cells, there was a 100-fold increase in PGK activity, and in normal red cells, a threefold increase in PGK activity was observed. Parasite PGK could be recovered from isolated parasites, and a marked increase in heat instability of parasite PGK as compared with the host cell enzyme was noted. Neither cDNA probe was found to cross-react with DNA sequences in the parasite genome. It is concluded that the parasite has no requirement for DPGM, and probably has no gene for this enzyme. On the other hand, the parasite does require PGK, (an adenosine triphosphate [ATP] generating enzyme) and synthesizes its own enzyme, which must have been encoded in the parasite genome. The parasite PGK gene most likely lacks sufficient homology to be detected by a human cDNA probe. Enzymopathic red cells are useful tools for elucidating the glycolytic enzymology of parasites and their co-evolution with their human hosts.
The Effect of Antidepressants on Mesenchymal Stem Cell Differentiation.
Kruk, Jeffrey S; Bermeo, Sandra; Skarratt, Kristen K; Fuller, Stephen J; Duque, Gustavo
2018-02-01
Use of antidepressant medications has been linked to detrimental impacts on bone mineral density and osteoporosis; however, the cellular basis behind these observations remains poorly understood. The effect does not appear to be homogeneous across the whole class of drugs and may be linked to affinity for the serotonin transporter system. In this study, we hypothesized that antidepressants have a class- and dose-dependent effect on mesenchymal stem cell (MSC) differentiation, which may affect bone metabolism. Human MSCs (hMSCs) were committed to differentiate when either adipogenic or osteogenic media was added, supplemented with five increasing concentrations of amitriptyline (0.001-10 µM), venlafaxine (0.01-25 µM), or fluoxetine (0.001-10 µM). Alizarin red staining (mineralization), alkaline phosphatase (osteoblastogenesis), and oil red O (adipogenesis) assays were performed at timed intervals. In addition, cell viability was assessed using a MTT. We found that fluoxetine had a significant inhibitory effect on mineralization. Furthermore, adipogenic differentiation of hMSC was affected by the addition of amitriptyline, venlafaxine, and fluoxetine to the media. Finally, none of the tested medications significantly affected cell survival. This study showed a divergent effect of three antidepressants on hMSC differentiation, which appears to be independent of class and dose. As fluoxetine and amitriptyline, but not venlafaxine, affected both osteoblastogenesis and adipogenesis, this inhibitory effect could be associated to the high affinity of fluoxetine to the serotonin transporter system.
Reconstructing the metric of the local Universe from number counts observations
DOE Office of Scientific and Technical Information (OSTI.GOV)
Vallejo, Sergio Andres; Romano, Antonio Enea, E-mail: antonio.enea.romano@cern.ch
Number counts observations available with new surveys such as the Euclid mission will be an important source of information about the metric of the Universe. We compute the low red-shift expansion for the energy density and the density contrast using an exact spherically symmetric solution in presence of a cosmological constant. At low red-shift the expansion is more precise than linear perturbation theory prediction. We then use the local expansion to reconstruct the metric from the monopole of the density contrast. We test the inversion method using numerical calculations and find a good agreement within the regime of validity ofmore » the red-shift expansion. The method could be applied to observational data to reconstruct the metric of the local Universe with a level of precision higher than the one achievable using perturbation theory.« less
Disulphide-reduced psoriasin is a human apoptosis-inducing broad-spectrum fungicide
Hein, Kyaw Zaw; Takahashi, Hitoshi; Tsumori, Toshiko; Yasui, Yukihiko; Nanjoh, Yasuko; Toga, Tetsuo; Wu, Zhihong; Grötzinger, Joachim; Jung, Sascha; Wehkamp, Jan; Schroeder, Bjoern O.; Schroeder, Jens M.; Morita, Eishin
2015-01-01
The unexpected resistance of psoriasis lesions to fungal infections suggests local production of an antifungal factor. We purified Trichophyton rubrum-inhibiting activity from lesional psoriasis scale extracts and identified the Cys-reduced form of S100A7/psoriasin (redS100A7) as a principal antifungal factor. redS100A7 inhibits various filamentous fungi, including the mold Aspergillus fumigatus, but not Candida albicans. Antifungal activity was inhibited by Zn2+, suggesting that redS100A7 interferes with fungal zinc homeostasis. Because S100A7-mutants lacking a single cysteine are no longer antifungals, we hypothesized that redS100A7 is acting as a Zn2+-chelator. Immunogold electron microscopy studies revealed that it penetrates fungal cells, implicating possible intracellular actions. In support with our hypothesis, the cell-penetrating Zn2+-chelator TPEN was found to function as a broad-spectrum antifungal. Ultrastructural analyses of redS100A7-treated T. rubrum revealed marked signs of apoptosis, suggesting that its mode of action is induction of programmed cell death. TUNEL, SYTOX-green analyses, and caspase-inhibition studies supported this for both T. rubrum and A. fumigatus. Whereas redS100A7 can be generated from oxidized S100A7 by action of thioredoxin or glutathione, elevated redS100A7 levels in fungal skin infection indicate induction of both S100A7 and its reducing agent in vivo. To investigate whether redS100A7 and TPEN are antifungals in vivo, we used a guinea pig tinea pedes model for fungal skin infections and a lethal mouse Aspergillus infection model for lung infection and found antifungal activity in both in vivo animal systems. Thus, selective fungal cell-penetrating Zn2+-chelators could be useful as an urgently needed novel antifungal therapeutic, which induces programmed cell death in numerous fungi. PMID:26438863
Code of Federal Regulations, 2014 CFR
2014-04-01
... STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Red Blood Cells § 640.16 Processing. (a) Separation. Within the..., Red Blood Cells may be prepared either by centrifugation, done in a manner that will not tend to... for Red Blood Cells shall be the original blood containers unless the method of processing requires a...
42 CFR 493.1271 - Standard: Immunohematology.
Code of Federal Regulations, 2014 CFR
2014-10-01
... must be tested with known A1 and B red cells. (3) The laboratory must determine the D(Rho) type by testing unknown red cells with anti-D (anti-Rho) blood typing reagent. (b) Immunohematological testing and...) through (e). (2) The laboratory must determine ABO group by concurrently testing unknown red cells with...
Code of Federal Regulations, 2012 CFR
2012-04-01
... STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Red Blood Cells § 640.16 Processing. (a) Separation. Within the..., Red Blood Cells may be prepared either by centrifugation, done in a manner that will not tend to... for Red Blood Cells shall be the original blood containers unless the method of processing requires a...
9 CFR 113.115 - Staphylococcus Aureus Bacterin-Toxoid.
Code of Federal Regulations, 2011 CFR
2011-01-01
... standard antitoxin produces a 50 percent hemolysis of rabbit red blood cells. (6) Incubate toxin-antitoxin... drawn rabbit red blood cells suspended in normal saline to each tube. Mix and incubate the combined... determining the size of the button produced by the unlysed red blood cells. (8) Determine the units of...
Code of Federal Regulations, 2013 CFR
2013-04-01
... STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Red Blood Cells § 640.16 Processing. (a) Separation. Within the..., Red Blood Cells may be prepared either by centrifugation, done in a manner that will not tend to... for Red Blood Cells shall be the original blood containers unless the method of processing requires a...
42 CFR 493.1271 - Standard: Immunohematology.
Code of Federal Regulations, 2011 CFR
2011-10-01
... must be tested with known A1 and B red cells. (3) The laboratory must determine the D(Rho) type by testing unknown red cells with anti-D (anti-Rho) blood typing reagent. (b) Immunohematological testing and...) through (e). (2) The laboratory must determine ABO group by concurrently testing unknown red cells with...
9 CFR 113.115 - Staphylococcus Aureus Bacterin-Toxoid.
Code of Federal Regulations, 2013 CFR
2013-01-01
... standard antitoxin produces a 50 percent hemolysis of rabbit red blood cells. (6) Incubate toxin-antitoxin... drawn rabbit red blood cells suspended in normal saline to each tube. Mix and incubate the combined... determining the size of the button produced by the unlysed red blood cells. (8) Determine the units of...
42 CFR 493.1271 - Standard: Immunohematology.
Code of Federal Regulations, 2013 CFR
2013-10-01
... must be tested with known A1 and B red cells. (3) The laboratory must determine the D(Rho) type by testing unknown red cells with anti-D (anti-Rho) blood typing reagent. (b) Immunohematological testing and...) through (e). (2) The laboratory must determine ABO group by concurrently testing unknown red cells with...
Code of Federal Regulations, 2011 CFR
2011-04-01
... STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Red Blood Cells § 640.16 Processing. (a) Separation. Within the..., Red Blood Cells may be prepared either by centrifugation, done in a manner that will not tend to... for Red Blood Cells shall be the original blood containers unless the method of processing requires a...
9 CFR 113.115 - Staphylococcus Aureus Bacterin-Toxoid.
Code of Federal Regulations, 2012 CFR
2012-01-01
... standard antitoxin produces a 50 percent hemolysis of rabbit red blood cells. (6) Incubate toxin-antitoxin... drawn rabbit red blood cells suspended in normal saline to each tube. Mix and incubate the combined... determining the size of the button produced by the unlysed red blood cells. (8) Determine the units of...
9 CFR 113.115 - Staphylococcus Aureus Bacterin-Toxoid.
Code of Federal Regulations, 2014 CFR
2014-01-01
... standard antitoxin produces a 50 percent hemolysis of rabbit red blood cells. (6) Incubate toxin-antitoxin... drawn rabbit red blood cells suspended in normal saline to each tube. Mix and incubate the combined... determining the size of the button produced by the unlysed red blood cells. (8) Determine the units of...
9 CFR 113.115 - Staphylococcus Aureus Bacterin-Toxoid.
Code of Federal Regulations, 2010 CFR
2010-01-01
... standard antitoxin produces a 50 percent hemolysis of rabbit red blood cells. (6) Incubate toxin-antitoxin... drawn rabbit red blood cells suspended in normal saline to each tube. Mix and incubate the combined... determining the size of the button produced by the unlysed red blood cells. (8) Determine the units of...
42 CFR 493.1271 - Standard: Immunohematology.
Code of Federal Regulations, 2012 CFR
2012-10-01
... must be tested with known A1 and B red cells. (3) The laboratory must determine the D(Rho) type by testing unknown red cells with anti-D (anti-Rho) blood typing reagent. (b) Immunohematological testing and...) through (e). (2) The laboratory must determine ABO group by concurrently testing unknown red cells with...
21 CFR 640.17 - Modifications for specific products.
Code of Federal Regulations, 2010 CFR
2010-04-01
... (CONTINUED) BIOLOGICS ADDITIONAL STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Red Blood Cells § 640.17 Modifications for specific products. Red Blood Cells Frozen: A cryophylactic substance may be added to the Red Blood Cells for extended manufacturers' storage at −65° C or colder, provided the manufacturer submits...
Rheological properties of RBC in the microcirculation of mammalian skeletal muscle. [red blood cells
NASA Technical Reports Server (NTRS)
Ehrenberg, M. H.
1974-01-01
In the investigation the established technique of direct microscopic viewing was combined with the use of a closed circuit television system and cinematography. The red cell flow patterns in all capillaries were found to be oscillatory with characteristic cycle frequencies and amplitudes for all concentrations of inspired oxygen greater than 8%. Generally, there was a transient decrease in mean flow rate with increasing severity of hypoxia, with a gradual return toward control values. Red cell flow patterns are discussed along with questions of red cell configuration.
Comparative Study of Antimalarial and Other Drugs on G6PD Deficient Red Cells.
33063 (1600 mg x day for 6 days) and WR 30090 (690 mg x day for 3- 6 days) demonstrated that these drugs were not hemolytic for G6PD deficient red cells...The studies concerning the effects of DFD on G6PD deficient red cells of the A- and B- variants were completed during the course of this contract...DFD is especially hemolytic even at low single dosages for G6PD deficient red cells of the B- type. The investigations on the new antimalarials WR
DOE Office of Scientific and Technical Information (OSTI.GOV)
Heiden, R.A.; Locko, R.C.; Stent, T.R.
1991-03-01
A 25-year-old gravid woman, homozygous for sickle cell anemia, with a history of recent deep venous thrombosis, was examined using Tc-99m labeled red blood cell venography for recurrent thrombosis. Although negative for thrombus, the study presented an unusual incidental finding: the patient's peripheral bone marrow was hyperemic in a distribution consistent with peripheral red bone marrow expansion. Such a pattern has not been documented before using this technique. This report supports other literature that has demonstrated hyperemia of peripheral red bone marrow in other hemolytic anemias. This finding may ultimately define an additional role of scintigraphy in assessing the pathophysiologicmore » status of the sickle cell patient.« less
Red Blood Cell Hematocrit Influences Platelet Adhesion Rate in a Microchannel
NASA Astrophysics Data System (ADS)
Spann, Andrew; Campbell, James; Fitzgibbon, Sean; Rodriguez, Armando; Shaqfeh, Eric
2014-11-01
The creation of a blood clot to stop bleeding involves platelets forming a plug at the site of injury. Red blood cells indirectly play a role in ensuring that the distribution of platelets across the height of the channel is not uniform - the contrast in deformability and size between platelets and red blood cells allows the platelets to preferentially marginate close to the walls. We perform 3D boundary integral simulations of a suspension of platelets and red blood cells in a periodic channel with a model that allows for platelet binding at the walls. The relative rate of platelet activity with varying hematocrit (volume fraction of red blood cells) is compared to experiments in which red blood cells and platelets flow through a channel coated with von Willebrand factor. In the simulations as well as the experiments, a decrease in hematocrit of red blood cells is found to reduce the rate at which platelets adhere to the channel wall in a manner that is both qualitatively and quantitatively similar. We conclude with a discussion of the tumbling and wobbling motions of platelets in 3D leading up to the time at which the platelets bind to the wall. Funded by Stanford Army High Performance Computing Research Center, experiments by US Army Institute of Surgical Research.
Can red-light 5-aminolevulinic photodynamic therapy cure port wine stains on comb animal model?
Lai, Yongxian; Zhang, Haiyan; Wei, Minglei; Ji, Jie; Shi, Lei; Wang, Peiru; Wang, Bo; Huang, Zheng; Wang, Xiuli
2018-06-01
To study the curative effect of red-light 5-Aminolevulinic photodynamic therapy(ALA-PDT) to port wine stains(PWS) on comb animal model. 160 male cocks were randomly divided into 16 groups. The ALA only group was given ALA only topical or systemic application. Light only groups were only given 630 nm red light irradiation with different light density. ALA-PDT groups were given red light after the application of topical or systemic ALA. PDL group was given PDL irradiation. The distribution of fluorescence in tissue after topical or systemic application of ALA was detected. The morphological changes, the pathological changes and the capillary reduction rate of the comb were observed after treatment for 0, 1, 3, 5, 7, 14 days. The PpIX fluorescence generated after topical and systemic application of ALA. In the topical ALA-PDT group at low light density 80 J/cm 2 , the morphology and the histopathology had no obvious change. While under 160 J/cm 2 and 200 J/cm 2 light density, severe erosion and thick scab appeared. The histopathology showed epidermal necrosis and loss. The immunohistochemistry showed that there was no significant change in the number of capillaries under different light density (P > 0.05). In the systemic ALA-PDT group under low light density 80 J/cm 2 , only partial erosion and thin scab was observed on the treatment side. With the increase of light density, thick charred crust and even scar was observed. The histopathology showed that there were different degrees of damage to dermal and epidermal tissues. And the immunohistochemistry showed the capillary reduced significantly in the treatment side (P < 0.01). In control group, the comb is ruddy and plump. These results suggest that either topical or systemic red-light ALA-PDT is not suitable treatment methods for PWS. Copyright © 2018 Elsevier B.V. All rights reserved.
Image classification of unlabeled malaria parasites in red blood cells.
Zheng Zhang; Ong, L L Sharon; Kong Fang; Matthew, Athul; Dauwels, Justin; Ming Dao; Asada, Harry
2016-08-01
This paper presents a method to detect unlabeled malaria parasites in red blood cells. The current "gold standard" for malaria diagnosis is microscopic examination of thick blood smear, a time consuming process requiring extensive training. Our goal is to develop an automate process to identify malaria infected red blood cells. Major issues in automated analysis of microscopy images of unstained blood smears include overlapping cells and oddly shaped cells. Our approach creates robust templates to detect infected and uninfected red cells. Histogram of Oriented Gradients (HOGs) features are extracted from templates and used to train a classifier offline. Next, the ViolaJones object detection framework is applied to detect infected and uninfected red cells and the image background. Results show our approach out-performs classification approaches with PCA features by 50% and cell detection algorithms applying Hough transforms by 24%. Majority of related work are designed to automatically detect stained parasites in blood smears where the cells are fixed. Although it is more challenging to design algorithms for unstained parasites, our methods will allow analysis of parasite progression in live cells under different drug treatments.
Biosignatures of Kerala red rain cells: Implications in understanding their origin
NASA Astrophysics Data System (ADS)
Gangappa, R.; Thomas, M.; Hogg, S.
2013-09-01
The red rain that fell over Kerala, southern India (2001-2012) was characterised by the red pigmented particles. Earlier proposal claiming that these are known algal bloom blown from trees (Sampath et al, 2001; DiGregorio, 2007) has been studied by us and disproved. Also, further investigation reporting their extraordinary properties including a suggestion that they lack DNA (Louis and Kumar 2003; 2006; 2008) has been invalidated (Gangappa and Hogg, 2013). However, their claim regarding the growth and replication of these cells at 300ºC needs more investigation if it is to gain acceptance. Current study provide evidences regarding the biological properties of Kerala red rain cells to gain insights into environmental conditions from which they may have originated. Combined with various research strategies and high resolution instruments, we have demonstrated the following interesting properties of Kerala red rain cells: (1) unusually thick external envelope enclosing the central core; (2)stability of red pigment at temperatures about 100ºC and pH variations; (3) absence of eukaryotic ultrastructures; (4) possible replication at 121ºC with nanostructures (possible daughter cells) having similar morphological features inside the large mother cells at such high temperature. They contain high percentage of carbon, iron, silicon and aluminum and often enclosed in a silicon rich biofilms. Further investigation shows that the positive detection of DNA in these cells was possible only after the complete removal of red pigment, thereby providing an explanation for the negative outcome of earlier studies in this regard. Moreover, evidences are shown to support that these cells contain high amounts of UV absorbing compounds, porphyrin complexes and possible scytonemin. Kerala red rain cells may prove to be polyextermophiles belonging to prokaryotes and may have possibly originated from the environment containing above mentioned chemical elements, high energy UV exposure and possible high temperatures. This may be of high interest and red rain cells can be viewed as a possible candidate in future Astrobiological investigations.
Radar and photometric measurements of an intense type A red aurora
NASA Technical Reports Server (NTRS)
Robinson, R. M.; Mende, S. B.; Vondrak, R. R.; Kozyra, J. U.; Nagy, A. F.
1985-01-01
On the evening of March 5, 1981, an intense, type A red aurora appeared over southern Alaska. Radar and photometric measurements were made of the aurora from the Chatanika radar site. The line of sight intensity of the 630.0-nm emissions exceeded 150 kR and was accompanied by enhanced emissions at 486.1 and 427.8 nm. The Chatanika radar measured electron densities of 10 to the 6th per cu cm and electron temperatures of 6000 K at an altitude of 400 km and an invariant latitude of 59 deg in association with the aurora. Comparison of optical and radar measurements indicated that the 630.0-nm emissions were produced to a large degree by thermal excitation of O(1D) in the region of high electron temperatures and densities. Model calculations indicate that the observed density and temperature enhancements and the related optical emissions were the results of a relatively short duration (5-10 min) pulse of precipitating, low-energy (about 30 eV) electrons. Whereas conventional stable auroral red arcs are associated with a gradual decrease in ring current energy density during the recovery phase of a magnetic storm, the type A red aurora may be produced by impulsive ring current energy loss during the main phase.
Characterization of the increased binding of acetaldehyde to red blood cells in alcoholics.
Hernández-Muñoz, R; Baraona, E; Blacksberg, I; Lieber, C S
1989-10-01
Using equilibrium dialysis, we found that acetaldehyde, at the levels commonly occurring after ethanol ingestion, did not bind detectably to plasma proteins, but there was significant binding to red blood cells, more in alcoholics than in nonalcoholics. The binding to red blood cells was inhibited by pyridoxal phosphate and N-ethylmaleimide, suggesting adduction to amino and thiol groups. Binding kinetics were consistent with at least two sites. The one with the highest affinity for acetaldehyde corresponded to hemoglobin. Its affinity and Bmax were not changed in alcoholics, but these binding sites accounted for only 44% of the sites available in the red blood cells of alcoholics and 80% of those in controls. Moreover, this binding was not inhibited by N-ethylmaleimide. There was no detectable binding to red cell ghosts. Nonprotein binding was then assessed by changes in NADH produced by the addition of protein-free fractions of the cells to an alcohol dehydrogenase system in equilibrium; this revealed a second binder of lower affinity, larger capacity and with sensitivity to both inhibitors. This binding (possibly due to thiazolidine formation with cysteine) was enhanced in alcoholics, whose red blood cell cysteine content was doubled. Levels of red blood cell cysteine and acetaldehyde remained high for 2 weeks after withdrawal. Because of the prolonged persistence after withdrawal, these changes may provide new markers of alcoholism.
Sudprasert, Krisda; Peungthum, Patjaree; Vongsakulyanon, Apirom; Amarit, Ratthasart; Somboonkaew, Armote; Sutapun, Boonsong; Kitpoka, Pimpun; Kunakorn, Mongkol; Srikhirin, Toemsak
2015-02-07
A flow-induced cell movement assay combined with a surface plasmon resonance (SPR) technique was developed to quantify the agglutination strength, derived from the standard tube-agglutination test. Red blood cells (RBCs), based on the ABO blood group system, were specifically captured by anti-A and/or anti-B antibodies immobilized on a sensor surface. The agglutination strength corresponds to the amount of antigen-antibody interactions or the strength of RBC adhesion. Under a shear flow, the adherent RBCs were forced to move out of the region of interest with different average cell velocities (vc) depending upon the adhesion strength and wall shear stress (WSS). That is, a higher adhesion strength (higher agglutination strength) or lower WSS represents a lower vc or vice versa. In this work, the agglutination strength was derived from the vc that was calculated from the time derivative of the relative SPR signal by using a simple model of cell movement response, whose validity was verified. The vc values of different samples were correlated with their agglutination strengths at a given WSS and antibody surface density. The vc decreased as the agglutination strength increased, which can be considered as a linear regression. The coefficient of variation of the calculated vc decreased to 0.1 as vc increased to 30 μm min(-1). The sensitivity of this assay can be controlled by optimizing the antibody surface density or the WSS. This assay has the capability to resolve the antigen density of A1 and B RBCs from that of A1B RBCs.
Photodynamic effects of 31 different phthalocyanines on a human keratinocyte cell line.
Jančula, Daniel; Maršálek, Blahoslav; Babica, Pavel
2013-10-01
Phthalocyanines (Pcs, colored macromolecular compounds with the ability to generate singlet oxygen) represent a promising group of photosensitizers due to their intense absorption in the red and UV portion of the spectrum which leads to their excitation. In order to characterize possible toxic effects associated with eventual practical use and application of these chemicals, we employed an in vitro cell culture model to evaluate cytotoxic effects of 31 different phthalocyanines using neutral red uptake assay. An immortalized human keratinocyte cell line HaCaT was exposed to the tested chemicals for 2 or 24h, either with or without illumination in the last 60 min of the exposure period. After 2- or 24-h exposure without illumination, no cytotoxic effects or weak cytotoxic effects were induced by any Pc under the study and EC50 values could not be obtained within the tested concentration ranges (1.25-20 mg L(-1) or 0.625-10 mg L(-1)). On the other hand, exposure to phthalocyanines under illumination induced a significant cytotoxic effect. The most pronounced cytotoxicity was elicited by Pcs previously shown to have high positive charge densities at peripheral parts of substituent groups, which is most likely the factor responsible for the binding of Pc to negatively charged membranes on the cell surface and thus guaranteeing the tight connection necessary for the singlet oxygen attack on the cell surface. Copyright © 2013 Elsevier Ltd. All rights reserved.
Ayato, Yusuke; Sakurai, Kenichiro; Fukunaga, Saori; Suganuma, Takuya; Yamagiwa, Kiyofumi; Shiroishi, Hidenobu; Kuwano, Jun
2014-05-15
A red blood cell (RBC) from human exhibited direct electron transfer (DET) activity on a bare indium tin oxide (ITO) electrode. A formal potential of -0.152 V vs. a silver-silver chloride saturated potassium chloride (Ag|AgCl|KCl(satd.)) was estimated for the human RBC (type AB) from a pair of redox peaks at around 0.089 and -0.215 V (vs. Ag|AgCl|KCl(satd.)) on cyclic voltammetric (CV) measurements in a phosphate buffered saline (PBS; 39 mM; pH 7.4) solution. The results agreed well with those of a redox couple for iron-bearing heme groups in hemoglobin molecules (HbFe(II)/HbFe(III)) on the bare ITO electrodes, indicated that DET active species were hemoglobin (Hb) molecules encapsulated by a phospholipid bilayer membrane of the human RBC. The quantity of electrochemically active Hb in the human RBC was estimated to be 30 pmol cm(-2). In addition, the human RBC exhibited oxygen reduction reaction (ORR) activity in the dioxygen (O2) saturated PBS solution at the negative potential from ca. -0.15 V (vs. Ag|AgCl|KCl(satd.)). A single cell test proved that a biofuel cell (BFC) with an O2|RBC|ITO cathode showed the open-circuit voltage (OCV) of ca. 0.43 V and the maximum power density of ca. 0.68 μW cm(-2). © 2013 Published by Elsevier B.V.
Inability to detect transferrin receptors on P. falciparum parasitized red cells.
Pollack, S; Schnelle, V
1988-01-01
The mechanism by which P. falciparum takes up iron from transferrin has been explored. Binding of 125I labelled transferrin to parasitized red cells at 37 degrees C is two-fold greater than to control cells; at 0 degrees C there is no significant difference. The binding is non-specific as judged from the following: it is not saturable; it is not limited to transferrin as lactoferrin (which has iron binding domains) and bovine serum albumin (which does not) also bind in excess to parasitized red cells. A transferrin receptor complex could not be demonstrated when parasitized red cells, to which 125I transferrin was bound, were solubilized in Triton X100. Previous observation showed that uptake of transferrin iron by parasitized red cells is not accompanied by equimolar uptake of transferrin protein. We therefore suggest that nonspecifically bound transferrin is endocytosed, that the protein is degraded and the iron selectively retained.
El Assal, Rami; Guven, Sinan; Gurkan, Umut Atakan; Gozen, Irep; Shafiee, Hadi; Dalbeyler, Sedef; Abdalla, Noor; Thomas, Gawain; Fuld, Wendy; Illigens, Ben M W; Estanislau, Jessica; Khoory, Joseph; Kaufman, Richard; Zylberberg, Claudia; Lindeman, Neal; Wen, Qi; Ghiran, Ionita; Demirci, Utkan
2014-09-03
Current red-blood-cell cryopreservation methods utilize bulk volumes, causing cryo-injury of cells, which results in irreversible disruption of cell morphology, mechanics, and function. An innovative approach to preserve human red-blood-cell morphology, mechanics, and function following vitrification in nanoliter volumes is developed using a novel cryo-ink integrated with a bioprinting approach. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Bookchin, Robert M; Etzion, Zipora; Lew, Virgilio L; Tiffert, Teresa
2009-03-01
The activity of the plasma membrane Ca(2+)-pump decreases steeply throughout the 120 days lifespan of normal human red blood cells. Experiments with isolated membrane preparations showed that glycation of a lysine residue near the catalytic site of the pump ATPase had a powerful inhibitory effect. This prompted the question of whether glycation is the mechanism of age-related decline in pump activity in vivo. It is important to investigate this mechanism because the Ca(2+) pump is a major regulator of Ca(2+) homeostasis in all cells. Its impaired activity in diabetic patients, continuously exposed to high glycation rates, may thus contribute to varied tissue pathology in this disease. We measured Ca(2+)-pump activity as a function of red cell age in red cells from diabetics continuously exposed to high glucose concentrations, as documented by their high mean levels of glycated haemoglobin. The distribution of Ca(2+)-pump activities was indistinguishable from that in non-diabetics, and the pattern of activity decline with cell age in the diabetics' red cells was identical to that observed in red cells from non-diabetics. These results indicate that in intact cells the Ca(2+) pump is protected from glycation-induced inactivation.
Arenas-Montes, A; Paniagua, J; Arenas, A; Lorca-Oró, C; Carbonero, A; Cano-Terriza, D; García-Bocanegra, I
2016-10-01
An epidemiological study was carried out to determine the spatial-temporal trends and risk factors potentially involved in the seropositivity to bluetongue virus (BTV) in hunting areas with presence of red deer (Cervus elaphus). A total of 60 of 98 (61.2%; CI95% : 51.6-70.9) hunting areas sampled presented at least one seropositive red deer. Antibodies against BTV were detected in juvenile animals during the hunting seasons 2007/2008 to 2013/2014 in 15 of 98 (15.3%) hunting areas, which indicates an uninterrupted circulation of BTV in this period. A multivariate logistic regression model showed that the red deer density at hunting area level (>22 individuals/km(2) ), the annual abundance of Culicoides imicola (>1.4 mosquitoes/sampling) and the goat density at municipality level (>24.1 individuals/km(2) ) were factors significantly associated with BTV seropositivity in hunting areas. Control measures against BTV in the studied area include vaccination programmes in wild and domestic ruminants, movement control in areas with high densities and abundance of red deer and C. imicola, respectively. Considering the potential risk of BTV re-emergence, red deer should be included in the BT surveillance programmes in regions where these species share habitats with livestock. © 2014 Blackwell Verlag GmbH.
Wannez, Adeline; Bailly, Nicolas; Alpan, Lutfiye; Gheldof, Damien; Douxfils, Jonathan; Deneys, Véronique; Bihin, Benoît; Chatelain, Bernard; Dogné, Jean-Michel; Chatelain, Christian; Mullier, François
2018-01-01
Background Thrombotic effects are possible complications of red blood cell transfusion. The generation and accumulation of procoagulant red blood cell extracellular vesicles during storage may play an important role in these thrombotic effects. The objective of this study was to assess the value of a simple phospholipid-dependent clot-based assay (STA®-Procoag-PPL) to estimate the procoagulant activity of stored red blood cells and changes in this activity during storage of the blood component. Materials and methods Extracellular vesicles from 12 red blood cell concentrates were isolated at 13 storage time-points and characterised by quantitative and functional methods: the degree of haemolysis (direct spectrophotometry), the quantification and determination of cellular origin (flow cytometry) and the procoagulant activity (thrombin generation and STA®-Procoag-PPL assays) were assessed. Results The mean clotting time of extracellular vesicles isolated from red blood cell concentrates decreased from 117.2±3.6 sec on the day of collection to 33.8±1.3 sec at the end of the storage period. This illustrates the phospholipid-dependent procoagulant activity of these extracellular vesicles, as confirmed by thrombin generation. Results of the peak of thrombin and the STA®-Procoag-PPL were well correlated (partial r=−0.41. p<0.001). In parallel, an exponential increase of the number of red blood cell-derived extracellular vesicles from 1,779/μL to 218,451/μL was observed. Discussion The STA®-Procoag-PPL is a potentially useful technique for assessing the procoagulant activity of a red blood cell concentrate. PMID:28287378
Yuan, Hong-Liang; Liu, Xiao-Lei; Liu, Ying-Jie
2014-01-01
Solanum nigrum L. has been used in traditional Chinese medicine because of its diuretic and antipyretic effects. The present research concerned effects of crude polysaccharides isolated from Solanum nigrum L. on erythrocyte membranes of tumor-bearing S180 and H22 in mice. Fluorescence- labeled red blood cell membranes were used with DPH fluorescence spectrophotometry to examine erythrocyte membrane fluidity, and colorimetry to determine degree of erythrocyte surface membrane blocking. Extent of reaction by tumor-bearing mice with the enzyme erythrocyte membrane bubble shadow detection of red cell membrane variation in the degree of closure before and after administration. Solanum nigrum polysaccharide could significantly improve the S180 and H22 tumor-bearing mice erythrocyte membrane fluidity, compared with the control group, the difference was significant (p<0.01), SNL can significantly improve the red blood cell membrane and then S180 tumor-bearing mice sealing ability, compared with the negative control group, the difference was significant(p<0.05, p<0.01). H22 tumor-bearing mice can increase red cell membrane and then sealing ability, the difference was significant (p<0.05). Solanum nigrum polysaccharide degree of fluidity and blocking two transplanted tumors in mice restored the ability to raise the red cell membrane has a significant effect. Solanum nigrum L.-type mice transplanted tumor can affect the red blood cell membrane fluidity and re-closed, through the red cell membrane of red blood cells to enhance the immune function of the possibility of erythrocyte immunity against tumor formation garland provide experimental basis.
Elebute, Modupe O; Choo, Louise; Mora, Ana; MacRury, Coral; Llewelyn, Charlotte; Purohit, Shilpi; Hicks, Vicky; Casey, Caroline; Malfroy, Moira; Deary, Alison; Reed, Tania; Meredith, Sarah; Manson, Lynn; Williamson, Lorna M
2013-03-01
This study, conducted for the UK Blood Transfusion Services (UKBTS), evaluated the clinical safety of red cells filtered through a CE-marked prion removal filter (P-Capt™). Patients requiring blood transfusion for elective procedures in nine UK hospitals were entered into a non-randomized open trial to assess development of red cell antibodies to standard red cell (RCC) or prion-filtered red cell concentrates (PF-RCC) at eight weeks and six months post-transfusion. Patients who received at least 1 unit of PF-RCC were compared with a control cohort given RCC only. About 917 PF-RCC and 1336 RCC units were transfused into 299 and 291 patients respectively. Twenty-six new red cell antibodies were detected post-transfusion in 10 patients in each arm, an overall alloimmunization rate of 4.4%. Neither the treatment arm [odds ratio (OR) 0.93, 95% confidence interval (CI) 0.3, 2.5] nor number of units transfused (OR 0.95, 95% CI 0.8, 1.1) had a significant effect on the proportion of patients who developed new alloantibodies. No pan-reactive antibodies or antibodies specifically against PF-RCC were detected. There was no difference in transfusion reactions between arms, and no novel transfusion-related adverse events clearly attributable to PF-RCC were seen. These data suggest that prion filtration of red cells does not reduce overall transfusion safety. This finding requires confirmation in large populations of transfused patients. © 2013 Blackwell Publishing Ltd.
Kevin T. Smith; Walter C. Shortle; Jody Jellison; Jon Connolly; Jonathan Schilling
2007-01-01
The decay of coarse woody debris is a key component in the formation of forest soil and in the biogeochemical cycles of Ca and Mg. We tracked changes in density and concentration of Ca and Mg in sapwood of red maple (Acer rubrum L.), red spruce (Picea rubens Sarg.), paper birch (Betula papyrifera Marsh.), and...
Shirmanova, Marina; Yuzhakova, Diana; Snopova, Ludmila; Perelman, Gregory; Serebrovskaya, Ekaterina; Lukyanov, Konstantin; Turchin, Ilya; Subochev, Pavel; Lukyanov, Sergey; Kamensky, Vladislav; Zagaynova, Elena
2015-01-01
The strong phototoxicity of the red fluorescent protein KillerRed allows it to be considered as a potential genetically encoded photosensitizer for the photodynamic therapy (PDT) of cancer. The advantages of KillerRed over chemical photosensitizers are its expression in tumor cells transduced with the appropriate gene and direct killing of cells through precise damage to any desired cell compartment. The ability of KillerRed to affect cell division and to induce cell death has already been demonstrated in cancer cell lines in vitro and HeLa tumor xenografts in vivo. However, the further development of this approach for PDT requires optimization of the method of treatment. In this study we tested the continuous wave (593 nm) and pulsed laser (584 nm, 10 Hz, 18 ns) modes to achieve an antitumor effect. The research was implemented on CT26 subcutaneous mouse tumors expressing KillerRed in fusion with histone H2B. The results showed that the pulsed mode provided a higher rate of photobleaching of KillerRed without any temperature increase on the tumor surface. PDT with the continuous wave laser was ineffective against CT26 tumors in mice, whereas the pulsed laser induced pronounced histopathological changes and inhibition of tumor growth. Therefore, we selected an effective regimen for PDT when using the genetically encoded photosensitizer KillerRed and pulsed laser irradiation.
21 CFR 660.33 - Testing of source material.
Code of Federal Regulations, 2011 CFR
2011-04-01
...) BIOLOGICS ADDITIONAL STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Reagent Red Blood Cells § 660... incorporated into the Reagent Red Blood Cell product shall be individually tested, with no fewer than two donor... tests for each factor. The Reagent Red Blood Cell product may be tested with a single donor source of...
21 CFR 864.6400 - Hematocrit measuring device.
Code of Federal Regulations, 2011 CFR
2011-04-01
..., racks, and a sealer and a holder. The device is used to measure the packed red cell volume in blood to determine whether the patient's total red cell volume is normal or abnormal. Abnormal states include anemia...). The packed red cell volume is produced by centrifuging a given volume of blood. (b) Classification...
Code of Federal Regulations, 2013 CFR
2013-04-01
... red blood cell concentration is less than 2 percent, the variance shall be no more than ±0.5... STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Reagent Red Blood Cells § 660.35 Labeling. In... of red blood cells in the suspension either as a discrete figure with a variance of more than ±1...
21 CFR 864.6400 - Hematocrit measuring device.
Code of Federal Regulations, 2014 CFR
2014-04-01
..., racks, and a sealer and a holder. The device is used to measure the packed red cell volume in blood to determine whether the patient's total red cell volume is normal or abnormal. Abnormal states include anemia...). The packed red cell volume is produced by centrifuging a given volume of blood. (b) Classification...
Code of Federal Regulations, 2012 CFR
2012-04-01
... red blood cell concentration is less than 2 percent, the variance shall be no more than ±0.5... STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Reagent Red Blood Cells § 660.35 Labeling. In... of red blood cells in the suspension either as a discrete figure with a variance of more than ±1...
21 CFR 660.33 - Testing of source material.
Code of Federal Regulations, 2012 CFR
2012-04-01
...) BIOLOGICS ADDITIONAL STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Reagent Red Blood Cells § 660... incorporated into the Reagent Red Blood Cell product shall be individually tested, with no fewer than two donor... tests for each factor. The Reagent Red Blood Cell product may be tested with a single donor source of...
21 CFR 864.6400 - Hematocrit measuring device.
Code of Federal Regulations, 2010 CFR
2010-04-01
..., racks, and a sealer and a holder. The device is used to measure the packed red cell volume in blood to determine whether the patient's total red cell volume is normal or abnormal. Abnormal states include anemia...). The packed red cell volume is produced by centrifuging a given volume of blood. (b) Classification...
21 CFR 660.33 - Testing of source material.
Code of Federal Regulations, 2014 CFR
2014-04-01
...) BIOLOGICS ADDITIONAL STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Reagent Red Blood Cells § 660... incorporated into the Reagent Red Blood Cell product shall be individually tested, with no fewer than two donor... tests for each factor. The Reagent Red Blood Cell product may be tested with a single donor source of...
42 CFR 409.87 - Blood deductible.
Code of Federal Regulations, 2012 CFR
2012-10-01
... after plasma is separated from whole blood. (2) A unit of packed red cells is treated as the equivalent...) Exception. The beneficiary is not responsible for the first 3 units of whole blood or packed red cells if.... In that case, the blood or red cells is deemed to have been replaced. (c) Provider's right to charge...
42 CFR 409.87 - Blood deductible.
Code of Federal Regulations, 2011 CFR
2011-10-01
... after plasma is separated from whole blood. (2) A unit of packed red cells is treated as the equivalent...) Exception. The beneficiary is not responsible for the first 3 units of whole blood or packed red cells if.... In that case, the blood or red cells is deemed to have been replaced. (c) Provider's right to charge...
21 CFR 864.6400 - Hematocrit measuring device.
Code of Federal Regulations, 2012 CFR
2012-04-01
..., racks, and a sealer and a holder. The device is used to measure the packed red cell volume in blood to determine whether the patient's total red cell volume is normal or abnormal. Abnormal states include anemia...). The packed red cell volume is produced by centrifuging a given volume of blood. (b) Classification...
42 CFR 409.87 - Blood deductible.
Code of Federal Regulations, 2014 CFR
2014-10-01
... after plasma is separated from whole blood. (2) A unit of packed red cells is treated as the equivalent...) Exception. The beneficiary is not responsible for the first 3 units of whole blood or packed red cells if.... In that case, the blood or red cells is deemed to have been replaced. (c) Provider's right to charge...
21 CFR 864.6400 - Hematocrit measuring device.
Code of Federal Regulations, 2013 CFR
2013-04-01
..., racks, and a sealer and a holder. The device is used to measure the packed red cell volume in blood to determine whether the patient's total red cell volume is normal or abnormal. Abnormal states include anemia...). The packed red cell volume is produced by centrifuging a given volume of blood. (b) Classification...
42 CFR 409.87 - Blood deductible.
Code of Federal Regulations, 2013 CFR
2013-10-01
... after plasma is separated from whole blood. (2) A unit of packed red cells is treated as the equivalent...) Exception. The beneficiary is not responsible for the first 3 units of whole blood or packed red cells if.... In that case, the blood or red cells is deemed to have been replaced. (c) Provider's right to charge...
Code of Federal Regulations, 2014 CFR
2014-04-01
... red blood cell concentration is less than 2 percent, the variance shall be no more than ±0.5... STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Reagent Red Blood Cells § 660.35 Labeling. In... of red blood cells in the suspension either as a discrete figure with a variance of more than ±1...
21 CFR 660.33 - Testing of source material.
Code of Federal Regulations, 2013 CFR
2013-04-01
...) BIOLOGICS ADDITIONAL STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Reagent Red Blood Cells § 660... incorporated into the Reagent Red Blood Cell product shall be individually tested, with no fewer than two donor... tests for each factor. The Reagent Red Blood Cell product may be tested with a single donor source of...
Code of Federal Regulations, 2011 CFR
2011-04-01
... red blood cell concentration is less than 2 percent, the variance shall be no more than ±0.5... STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Reagent Red Blood Cells § 660.35 Labeling. In... of red blood cells in the suspension either as a discrete figure with a variance of more than ±1...
21 CFR 660.33 - Testing of source material.
Code of Federal Regulations, 2010 CFR
2010-04-01
...) BIOLOGICS ADDITIONAL STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Reagent Red Blood Cells § 660... incorporated into the Reagent Red Blood Cell product shall be individually tested, with no fewer than two donor... tests for each factor. The Reagent Red Blood Cell product may be tested with a single donor source of...
Dispersal patterns of red foxes relative to population density
Allen, Stephen H.; Sargeant, Alan B.
1993-01-01
Factors affecting red fox (Vulpes vulpes) dispersal patterns are poorly understood but warranted investigation because of the role of dispersal in rebuilding depleted populations and transmission of diseases. We examined dispersal patterns of red foxes in North Dakota based on recoveries of 363 of 854 foxes tagged as pups and relative to fox density. Foxes were recovered up to 8.6 years after tagging; 79% were trapped or shot. Straight-line distances between tagging and recovery locations ranged from 0 to 302 km. Mean recovery distances increased with age and were greater for males than females, but longest individual recovery distances were by females. Dispersal distances were not related to population density for males (P = 0.36) or females (P = 0.96). The proportion of males recovered that dispersed was inversely related to population density (r = -0.94; n = 5; P = 0.02), but not the proportion of females (r = -0.49; n = 5; P = 0.40). Dispersal directions were not uniform for either males (P = 0.003) or females (P = 0.006); littermates tended to disperse in similar directions (P = 0.09). A 4-lane interstate highway altered dispersal directions (P = 0.001). Dispersal is a strong innate behavior of red foxes (especially males) that results in many individuals of both sexes traveling far from natal areas. Because dispersal distance was unaffected by fox density, populations can be rebuilt and diseases transmitted long distances regardless of fox abundance.
Reflection coefficients of permeant molecules in human red cell suspensions.
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.
Zerr, M A; Cox, C D; Johnson, W T; Drake, D R
1998-04-01
Establishment of a microbial community in the root canal system depends on numerous factors, of which nutrient availability may be one of the most important. We hypothesized that the presence of red blood cells or hemoglobin in this environment could cause shifts in microbial composition of communities, resulting in organisms such as Porphyromonas endodontalis becoming more dominant. An in vitro model system using mixed, batch cultures was performed with the bacteria P. endodontalis, Fusobacterium nucleatum, Peptostreptococcus micros and Campylobacter rectus. Bacteria were cultured in media with or without the addition of washed red blood cells, hemoglobin, or serum. Cyclic growth studies revealed that P. endodontalis was lost from the community of organisms after three cycles. However, inclusion of red blood cells resulted in establishment of this organism. Moreover, red blood cells added to pure cultures of P. endodontalis substantially enhanced growth and protected the organisms from oxygen. We conclude that the presence of red blood cells could result in shifts of microbial communities of organisms within the root canal system.
Ex-vivo expansion of red blood cells: How real for transfusion in humans?
Migliaccio, Anna Rita; Masselli, Elena; Varricchio, Lilian; Whitsett, Carolyn
2013-01-01
Blood transfusion is indispensable for modern medicine. In developed countries, the blood supply is adequate and safe but blood for alloimmunized patients is often unavailable. Concerns are increasing that donations may become inadequate in the future as the population ages prompting a search for alternative transfusion products. Improvements in culture conditions and proof-of-principle studies in animal models have suggested that ex-vivo expanded red cells may represent such a product. Compared to other cell therapies transfusion poses the unique challenge of requiring great cell doses (2.5 × 1012 cells vs 107 cells). Although production of such cell numbers is theoretically possible, current technologies generate red cells in numbers sufficient only for safety studies. It is conceived that by the time these studies will be completed, technical barriers to mass cell production will have been eliminated making transfusion with ex-vivo generated red cells a reality. PMID:22177597
Effect of 2,3-diphosphoglycerate on oxygen affinity of blood in sickle cell anemia
Charache, Samuel; Grisolia, Santiago; Fiedler, Adam J.; Hellegers, Andre E.
1970-01-01
Blood of patients with sickle cell anemia (SS) exhibits decreased affinity for oxygen, although the oxygen affinity of hemoglobin S is the same as that of hemoglobin A. SS red cells contain more 2,3-diphosphoglycerate (DPG) than normal erythrocytes. The oxygen affinity of hemolyzed red cells is decreased by added DPG, and hemolysates prepared from SS red cells do not differ from normal hemolysates in this regard. Reduction of oxygen affinity to the levels found in intact SS red cells required DPG concentrations in excess of those found in most SS patients. The same was true of oxygen affinity of patients with pyruvate kinase deficiency. Other organic phosphates, as well as inorganic ions, are known to alter the oxygen affinity of dilute solutions of hemoglobin. These substances, the state of aggregation of hemoglobin molecules, and cytoarchitectural factors probably play roles in determining oxygen affinity of both normal and SS red cells. PMID:5443181
Liu, Xu; Chen, Ben; Chen, Lulan; Ren, Wan-Ting; Liu, Juan; Wang, Guoxiang; Fan, Wei; Wang, Xin; Wang, Yun
2013-01-01
Phenol red is widely used in cell culture as a pH indicator. Recently, it also has been reported to have estrogen-like bioactivity and be capable of promoting cell proliferation in different cell lines. However, the effect of phenol red on primary neuronal culture has never been investigated. By using patch clamp technique, we demonstrated that hippocampal pyramidal neurons cultured in neurobasal medium containing no phenol red had large depolarization-associated epileptiform bursting activities, which were rarely seen in neurons cultured in phenol red-containing medium. Further experiment data indicate that the suppressive effect of the phenol red on the abnormal epileptiform burst neuronal activities was U-shape dose related, with the most effective concentration at 28 µM. In addition, this concentration related inhibitory effect of phenol red on the epileptiform neuronal discharges was mimicked by 17-β-estradiol, an estrogen receptor agonist, and inhibited by ICI-182,780, an estrogen receptor antagonist. Our results suggest that estrogen receptor activation by phenol red in the culture medium prevents formation of abnormal, epileptiform burst activity. These studies highlight the importance of phenol red as estrogen receptor stimulator and cautions of careful use of phenol red in cell culture media. PMID:23560076
VARIATION IN ACCESSIBLE CELL SURFACE IMMUNOGLOBULIN AMONG ANTIBODY-FORMING CELLS
Nossal, G. J. V.; Lewis, Heather
1972-01-01
Spleen cells from CBA mice that had been primarily or secondarily immunized with sheep red blood cells were reacted at 0°C with a 125I-labeled polyvalent rabbit anti-mouse globulin reagent. After suitable washing, the cells were placed in a plaque-revealing monolayer and warmed to 37°C. Plaques appeared within 10–20 min. Single plaque-forming cells (PFC) were taken from the middle of plaques, were washed by micromanipulation, and were singly dried on glass slides. The amount of attached antireceptor was assessed by quantitative radioautography. Great variation in "receptor density" was encountered among the 258 single cells studied. However, early, immature PFC in both primary and secondary responses had statistically significantly more receptors than late, mature PFC. On any given day point, no difference was found between IgM- and IgG-forming cells. The results were consistent with the view that cells still able to be driven to further proliferation by antigen retain receptors, and conversely that cells, as they mature, lose both receptors and ability to be influenced by antigen. PMID:4554455
Horiuchi, Toshinori; Noguchi, Teruo; Kurita, Naoko; Yamaguchi, Ayako; Takeda, Masafumi; Sha, Keiichi; Nagahata, Toshihiro
2016-01-01
We present two patients developing intraoperative massive bleeding and showed ischemic changes in the electrocardiogram and circulatory collapse accompanied by severe anemia owing to the delay of red blood cell concentrate transfusion. One patient underwent hepatectomy and the other pancreaticoduodenectomy. Their lowest hemoglobin concentration was around 2 g x dl(-1), and they showed ischemic changes in the electrocardiogram and severe decreases in blood pressure. The former received compatible red blood cell concentrate and the latter received uncrossmatched same blood group red blood cell concentrate immediately, and their electrocardiogram and blood pressure quickly improved. To avoid life-threatening anemia, emergency red blood cell concentrate transfusion including compatible different blood group transfusion should be applied for intraoperative massive bleeding.
Red cell surface changes in cold agglutination
Salsbury, A. J.; Clarke, J. A.; Shand, W. S.
1968-01-01
Surface changes in red blood cells undergoing cold agglutination have been investigated using the Cambridge Stereoscan electron microscope. On incubation of red cells with a cold agglutinin of anti-I specificity at 4°C, circular shadows on the red cell membrane developed within 2 min. At the same time the membrane showed a granularity and processes began to develop on the surface. These processes increased in length, the processes of contiguous cells became interlinked and agglutination was complete after incubation of 1 hr. On warming an agglutinated specimen, the process was reversed with separation of red cells and retraction of the finger-like processes to yield discrete red cells of normal appearance. The addition of heparin in vivo prevented agglutination but did not inhibit surface changes completely. Complement appeared to play no part in the production of cold agglutination due to these antibodies or in the reversal of agglutination by warming. The significance of the surface changes described in relation to previous information on the mechanism of agglutination, has been discussed. ImagesFig. 1Fig. 2Fig. 3Fig. 4Fig. 5Fig. 6Fig. 7Fig. 8Fig. 9Fig. 10Fig. 11 PMID:5655472
Singhal, Deepak; Kutyna, Monika M.; Chhetri, Rakchha; Wee, Li Yan A.; Hague, Sophia; Nath, Lakshmi; Nath, Shriram V.; Sinha, Romi; Wickham, Nicholas; Lewis, Ian D.; Ross, David M.; Bardy, Peter G.; To, Luen Bik; Reynolds, John; Wood, Erica M.; Roxby, David J.; Hiwase, Devendra K.
2017-01-01
Up to 90% of patients with a myelodysplastic syndrome require red blood cell transfusion; nevertheless, comprehensive data on red cell alloimmunization in such patients are limited. This study evaluates the incidence and clinical impact of red cell alloimmunization in a large cohort of patients with myelodysplastic syndrome registered in the statewide South Australian-MDS registry. The median age of the 817 patients studied was 73 years, and 66% were male. The cumulative incidence of alloimmunization was 11%. Disease-modifying therapy was associated with a lower risk of alloimmunization while alloimmunization was significantly higher in patients with a revised International Prognostic Scoring System classification of Very Low, Low or Intermediate risk compared to those with a High or Very High risk (P=0.03). Alloantibodies were most commonly directed against antigens in the Rh (54%) and Kell (24%) systems. Multiple alloantibodies were present in 49% of alloimmunized patients. Although 73% of alloimmunized patients developed alloantibodies during the period in which they received their first 20 red cell units, the total number of units transfused was significantly higher in alloimmunized patients than in non-alloimmunized patients (90±100 versus 30±52; P<0.0001). In individual patients, red cell transfusion intensity increased significantly following alloimmunization (2.8±1.3 versus 4.1±2.0; P<0.0001). A significantly higher proportion of alloimmunized patients than non-alloimmunized patients had detectable autoantibodies (65% versus 18%; P<0.0001) and the majority of autoantibodies were detected within a short period of alloimmunization. In conclusion, this study characterizes alloimmunization in a large cohort of patients with myelodysplastic syndrome and demonstrates a signficant increase in red cell transfusion requirements following alloimmunization, most probably due to development of additional alloantibodies and autoantibodies, resulting in subclinical/clinical hemolysis. Strategies to mitigate alloimmunization risk are critical for optimizing red cell transfusion support. PMID:28983058
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 < 0.001). No significant difference was found between any parameter analyzed for outdoor and in-house collected single CPDA red cell units. There was significant lower percentage hemolysis (p < 0.001) and potassium (day 7 to day 14 - p < 0.05 and day 14 to day 28 - p < 0.001) in red cell units from day 7 onward until day 28 of storage in the leukoreduced quadruple bag as compared to the triple bag. The in-house single CPDA red cell units showed significantly more hemolysis (p < 0.001) as compared to the triple bags with SAGM additive solution after 28 days of storage. There is gradual increase in plasma hemoglobin and plasma potassium 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.
Modeling of SAR returns from a red pine stand
NASA Technical Reports Server (NTRS)
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.
Features of Red Sea Water Masses
NASA Astrophysics Data System (ADS)
Kartadikaria, Aditya; Hoteit, Ibrahim
2015-04-01
Features of Red Sea water mass can be divided into three types but best to be grouped into two different classes that are split at the potential density line σθ=27.4. The surface water (0-50 m) and the intermediate water (50-200 m) have nearly identical types of water mass. They appear as a maxima salinity layer for the water mass that has σθ > 26.0, and as a minimum salinity layer for water mass that has σθ < 26.0. These types of water masses are strongly affected by mixing that is controlled by seasonal variability, fresh water intrusion of the Gulf of Aden Intermediate Water (GAIW), and eddies variability. Two types of mixing; isopycnal and diapycnal mixing are part of important physical phenomena that explain the change of water mass in the Red Sea. The isopycnal mixing occurs at the neutral potential density line, connecting the Red Sea with its adjacent channel, the Gulf of Aden. Diapycnal mixing is found as a dominant mixing mode in the surface of the Red Sea Water and mainly due to energetic eddy activity. Density gradients, across which diapycnal mixing occurs, in the Red Sea are mainly due to large variations in salinity. The isolation of an extreme haline water mass below the thermocline contributes to the generation of the latitudinal shift and low diapycnal mixing. This finding further explains the difference of spatial kinetic mixing between the RSW and the Indian Ocean basin.
NASA Astrophysics Data System (ADS)
Trinh, Cam Tu; Tran, Thanh Huong; Bui, Trang Viet
2017-09-01
Nannochloropsis oculata cells were grown in f/2 modified medium of Chiu et al. (2009) supplemented with the plant growth regulators in different concentrations. Lipid accumulation of N. oculata cells was evaluated by using Nile Red dye and Fiji Image J with Analyze Particles. Indole-3-acetic acid (IAA) stimulated the increase of cell density in rapid growth phase (day 6) at high concentration (0.75 mg/L) and in slow growth phase (day 10) at lower concentration (0.50 mg/L). IAA, gibberellic acid (GA3) and zeatin increased content of chlorophyll a, in particular, in f/2 modified medium supplemented with 0.5 mg/L zeatin at the 10th day of culture. Roles of plant growth regulators in growth and lipid accumulation of N. oculata were discussed.
... of oxygen in the blood. The medical term is cyanosis. Considerations Red blood cells provide oxygen to body tissues. Most of ... blood cells are bright red and the skin is pinkish or red. Blood that has lost its oxygen is dark bluish- ...
De Franceschi, Lucia; Franco, Robert S; Bertoldi, Mariarita; Brugnara, Carlo; Matté, Alessandro; Siciliano, Angela; Wieschhaus, Adam J; Chishti, Athar H; Joiner, Clinton H
2013-02-01
Sickle cell disease (SCD) is a globally distributed hereditary red blood cell (RBC) disorder. One of the hallmarks of SCD is the presence of circulating dense RBCs, which are important in SCD-related clinical manifestations. In human dense sickle cells, we found reduced calpastatin activity and protein expression compared to either healthy RBCs or unfractionated sickle cells, suggesting an imbalance between activator and inhibitor of calpain-1 in favor of activator in dense sickle cells. Calpain-1 is a nonlysosomal cysteine proteinase that modulates multiple cell functions through the selective cleavage of proteins. To investigate the relevance of this observation in vivo, we evaluated the effects of the orally active inhibitor of calpain-1, BDA-410 (30 mg/kg/d), on RBCs from SAD mice, a mouse model for SCD. In SAD mice, BDA-410 improved RBC morphology, reduced RBC density (D(20); from 1106 ± 0.001 to 1100 ± 0.001 g/ml; P<0.05) and increased RBC-K(+) content (from 364 ± 10 to 429 ± 12.3 mmol/kg Hb; P<0.05), markedly reduced the activity of the Ca(2+)-activated K(+)channel (Gardos channel), and decreased membrane association of peroxiredoxin-2. The inhibitory effect of calphostin C, a specific inhibitor of protein kinase C (PKC), on the Gardos channel was eliminated after BDA-410 treatment, which suggests that calpain-1 inhibition affects the PKC-dependent fraction of the Gardos channel. BDA-410 prevented hypoxia-induced RBC dehydration and K(+) loss in SAD mice. These data suggest a potential role of BDA-410 as a novel therapeutic agent for treatment of SCD.
The incomplete anti-Rh antibody agglutination mechanism of trypsinized ORh+ red cells.
Margni, R A; Leoni, J; Bazzurro, M
1977-01-01
The capacity for binding to trypsinized and non-trypsinized ORh+ red cells, of the IgG incomplete anti-Rh antibody and its F(ab')2 and Fc fragments has been investigated. An analysis has also been made of the capacity of non-specific human IgG, aggregated non-specific human IgG, human IgM (19S) and IgM (7S), and of fragments Fcgamma, Fcmu and Fc5mu to inhibit the agglutination of trypsinized ORh+ red cells by the IgG incomplete anti-Rh antibody. The results obtained indicate that these antibodies behave in a similar manner to that of nonprecipitating antibodies, and that the agglutination of trypsinized red cells seems to be a mixed reaction due to the interaction of an Fab fragment with its Rh antigenic determinant present in the surface of a red cell and the Fc of the same molecule with a receptor for Fc present in adjacent red cells. The trypsin treatment apparently results in the liberation of occult Fc receptors. It has also been demonstrated that in the agglutination of ORh+ red cells by IgG incomplete anti-Rh antibody in the presence of albumin, interaction must occur in some manner between the albumin and the Fc fragment since the F(ab')2 fragment does not give rise to agglutination under such conditions. Images Figure 1 PMID:415968
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.
Bernstein, P S; Minior, V K; Divon, M Y
1997-11-01
The presence of elevated nucleated red blood cell counts in neonatal blood has been associated with fetal hypoxia. We sought to determine whether small-for-gestational-age fetuses with abnormal umbilical artery Doppler velocity waveforms have elevated nucleated red blood cell counts. Hospital charts of neonates with the discharge diagnosis of small for gestational age (birth weight < 10th percentile) who were delivered between October 1988 and June 1995 were reviewed for antepartum testing, delivery conditions, and neonatal outcome. We studied fetuses who had an umbilical artery systolic/diastolic ratio within 3 days of delivery and a complete blood cell count on the first day of life. Multiple gestations, anomalous fetuses, and infants of diabetic mothers were excluded. Statistical analysis included the Student t test, chi 2 analysis, analysis of variance, and simple and stepwise regression. Fifty-two infants met the inclusion criteria. Those with absent or reversed end-diastolic velocity (n = 19) had significantly greater nucleated red blood cell counts than did those with end-diastolic velocity present (n = 33) (nucleated red blood cells/100 nucleated cells +/- SD: 135.5 +/- 138 vs 17.4 +/- 23.7, p < 0.0001). These infants exhibited significantly longer time intervals for clearance of nucleated red blood cells from their circulation (p < 0.0001). They also had lower birth weights (p < 0.05), lower initial platelet count (p = 0.0006), lower arterial cord blood pH (p < 0.05), higher cord blood base deficit (p < 0.05), and an increased likelihood of cesarean section for "fetal distress" (p < 0.05). Multivariate analysis demonstrated that absent or reversed end-diastolic velocity (p < 0.0001) and low birth weight (p < 0.0001) contributed to the elevation of the nucleated red blood cell count, whereas gestational age at delivery was not a significant contributor. We observed significantly greater nucleated red blood cell counts and lower platelet counts in small-for-gestational-age fetuses with abnormal umbilical artery Doppler studies. This may suggest that antenatal thrombotic events lead to an increased placental impedance. Fetal response to this chronic condition may result in an increased nucleated red blood cell count.
Blood or spores? A cautionary note on interpreting cellular debris on human skeletal remains.
Cappella, A; Stefanelli, S; Caccianiga, M; Rizzi, A; Bertoglio, B; Sforza, C; Cattaneo, C
2015-07-01
The identification of red blood cells on both skeletal human remains and decomposed corpses is of remarkable importance in forensic sciences, irrespective of its diagnostic value; their presence is often perplexing and difficult to interpret especially when in the context of decomposition and taphonomical variables. Some clinical research has focused on the morphological changes of red blood cells over time by scanning electron microscopy (SEM), but no research has investigated whether botanical structures can be confused for red blood cells. Since some literature has recently presumed the detection of erythrocyte-like cells on skeletal remains (even ancient) as surely erythrocytes, and most have never taken into consideration the chance of an origin different from blood, such as botanical, the present study aims at verifying the possibility of confusion between erythrocytes and botanical cells by applying SEM analysis and at highlighting the pitfalls in this particular issue through a test submitted to pathologists and natural scientists asked to discriminate between red blood cells and different vegetal structures (60 images obtained by SEM analysis). The results showed that although there are diagnostic features useful in identifying red blood cells from botanical structures, some spores resulted very similar to decaying red blood cells, which calls for attention and great caution when studying decomposed human remains.
Inhibition of sickle red cell adhesion and vasoocclusion in the microcirculation by antioxidants.
Kaul, Dhananjay K; Liu, Xiao-du; Zhang, Xiaoqin; Ma, Li; Hsia, Carleton J C; Nagel, Ronald L
2006-07-01
In sickle cell anemia (SCA), inflammatory (i.e., intravascular sickling and transient vasoocclusive) events result in chronic endothelial activation. In addition to sickling behavior, sickle (SS) red blood cells exhibit abnormal interaction with the vascular endothelium, which is considered to have an important role in initiation of vasoocclusion. Upregulation of endothelial adhesion molecules caused by oxidants (and cytokines) may lead to increased SS red cell adhesion. We hypothesize that endothelial activation is indispensable in SS red cell adhesion to the endothelium and that antioxidants will have an inhibitory effect on this interaction. We examined the effect of selected antioxidants in ex vivo mesocecum vasculature, a well-established model that allows measurement of hemodynamic parameters and, by intravital microscopy, can allow quantification of adhesion. We tested antioxidant enzymes (SOD and catalase) and an intravascular SOD mimetic, polynitroxyl albumin (PNA), in the presence of platelet-activating factor (PAF); the latter causes endothelial oxidant generation and endothelial activation, which characterize SCA. In ex vivo preparations, PAF not only induced marked endothelial oxidant generation, it also enhanced SS red cell adhesion, resulting in frequent blockage of small-diameter venules. The adhesion, inversely related to venular diameter, and vasoocclusion were markedly inhibited by antioxidants, resulting in improved hemodynamics. PNA, the most effective antioxidant, also abolished SS red cell adhesion in non-PAF-activated preparations. Thus SS red cell adhesion and related vasoocclusion may be ameliorated by antioxidant therapy with a stable and long-acting molecule (e.g., PNA).
NASA Technical Reports Server (NTRS)
Trial, J.; Rice, L.; Alfrey, C. P.
2001-01-01
BACKGROUND: We have described the rapid destruction of young red blood cells (neocytolysis) in astronauts adapting to microgravity, in polycythemic high altitude dwellers who descend to sea level, and in patients with kidney disorders. This destruction results from a decrease in erythropoietin (EPO) production. We hypothesized that such EPO withdrawal could trigger physiological changes in cells other than red cell precursors and possibly lead to the uptake and destruction of young red cells by altering endothelial cell-macrophage interactions, most likely occurring in the spleen. METHODS: We identified EPO receptors on human splenic endothelial cells (HSEC) and investigated the responses of these cells to EPO withdrawal. RESULTS: A monolayer of HSEC, unlike human endothelial cells from aorta, glomerulus, or umbilical vein, demonstrated an increase in permeability upon EPO withdrawal that was accompanied by unique morphological changes. When HSEC were cultured with monocyte-derived macrophages (but not when either cell type was cultured alone), EPO withdrawal induced an increased ingestion of young red cells by macrophages when compared with the constant presence or absence of EPO. CONCLUSIONS: HSEC may represent a unique cell type that is able to respond to EPO withdrawal by increasing permeability and interacting with phagocytic macrophages, which leads to neocytolysis.
Pejov, Ljupčo; Panda, Manas K; Moriwaki, Taro; Naumov, Panče
2017-02-15
The range of unit cell orientations generated at the kink of a bent single crystal poses unsurmountable challenges with diffraction analysis and limits the insight into the molecular-scale mechanism of bending. On a plastically bent crystal of hexachlorobenzene, it is demonstrated here that spatially resolved microfocus infrared spectroscopy using synchrotron radiation can be applied in conjunction with periodic density functional theory calculations to predict spectral changes or to extract information on structural changes that occur as a consequence of bending. The approach reproduces well the observed trends, such as the wall effects, and provides estimations of the vibrational shifts, unit cell deformations, and intramolecular parameters. Generally, expansion of the lattice induces red-shift while compression induces larger blue-shift of the characteristic ν(C-C) and ν(C-Cl) modes. Uniform or non-uniform expansion or contraction of the unit cell of 0.1 Å results in shifts of several cm -1 , whereas deformation of the cell of 0.5° at the unique angle causes shifts of <0.5 cm -1 . Since this approach does not include parameters related to the actual stimulus by which the deformation has been induced, it can be generalized and applied to other mechanically, photochemically, or thermally bent crystals.
Hydraulics of high-yield orchard trees: a case study of three Malus domestica cultivars.
Beikircher, Barbara; De Cesare, Chiara; Mayr, Stefan
2013-12-01
The drought tolerance of three economically important apple cultivars, Golden Delicious, Braeburn and Red Delicious, was analysed. The work offers insights into the hydraulics of these high-yield trees and indicates a possible hydraulic limitation of carbon gain. The hydraulic safety and efficiency of branch xylem and leaves were quantified, drought tolerance of living tissues was measured and stomatal regulation, turgor-loss point and osmotic potential at full turgor were analysed. Physiological measurements were correlated with anatomical parameters, such as conduit diameter, cell-wall reinforcement, stomatal density and stomatal pore length. Hydraulic safety differed considerably between the three cultivars with Golden Delicious being significantly less vulnerable to drought-induced embolism than Braeburn and Red Delicious. In Golden Delicious, leaves were less resistant than branch xylem, while in the other cultivars leaves were more resistant than branch xylem. Hydraulic efficiency and xylem anatomical measurements indicate differences in pit properties, which may also be responsible for variations in hydraulic safety. In all three cultivars, full stomatal closure occurred at water potentials where turgor had already been lost and severe loss of hydraulic conductivity as well as damage to living cells had been induced. The consequential negative safety margins pose a risk for hydraulic failure but facilitate carbon gain, which is further improved by the observed high stomatal conductance. Maximal stomatal conductance was clearly seen to be related to stomatal density and size. Based on our results, these three high-yield Malus domestica Borkh. cultivars span a wide range of drought tolerances, appear optimized for maximal carbon gain and, thus, all perform best under well-managed growing conditions.
Shimabukuro, Marilia Kimie; Langhi, Larissa Gutman Paranhos; Cordeiro, Ingrid; Brito, José M.; Batista, Claudia Maria de Castro; Mattson, Mark P.; de Mello Coelho, Valeria
2016-01-01
We characterized cerebral Oil Red O-positive lipid-laden cells (LLC) of aging mice evaluating their distribution, morphology, density, functional activities and inflammatory phenotype. We identified LLC in meningeal, cortical and neurogenic brain regions. The density of cerebral LLC increased with age. LLC presenting small lipid droplets were visualized adjacent to blood vessels or deeper in the brain cortical and striatal parenchyma of aging mice. LLC with larger droplets were asymmetrically distributed in the cerebral ventricle walls, mainly located in the lateral wall. We also found that LLC in the subventricular region co-expressed beclin-1 or LC3, markers for autophagosome or autophagolysosome formation, and perilipin (PLIN), a lipid droplet-associated protein, suggesting lipophagic activity. Some cerebral LLC exhibited β galactosidase activity indicating a senescence phenotype. Moreover, we detected production of the pro-inflammatory cytokine TNF-α in cortical PLIN+ LLC. Some cortical NeuN+ neurons, GFAP+ glia limitans astrocytes, Iba-1+ microglia and S100β+ ependymal cells expressed PLIN in the aging brain. Our findings suggest that cerebral LLC exhibit distinct cellular phenotypes and may participate in the age-associated neuroinflammatory processes. PMID:27029648
Shimabukuro, Marilia Kimie; Langhi, Larissa Gutman Paranhos; Cordeiro, Ingrid; Brito, José M; Batista, Claudia Maria de Castro; Mattson, Mark P; Mello Coelho, Valeria de
2016-03-31
We characterized cerebral Oil Red O-positive lipid-laden cells (LLC) of aging mice evaluating their distribution, morphology, density, functional activities and inflammatory phenotype. We identified LLC in meningeal, cortical and neurogenic brain regions. The density of cerebral LLC increased with age. LLC presenting small lipid droplets were visualized adjacent to blood vessels or deeper in the brain cortical and striatal parenchyma of aging mice. LLC with larger droplets were asymmetrically distributed in the cerebral ventricle walls, mainly located in the lateral wall. We also found that LLC in the subventricular region co-expressed beclin-1 or LC3, markers for autophagosome or autophagolysosome formation, and perilipin (PLIN), a lipid droplet-associated protein, suggesting lipophagic activity. Some cerebral LLC exhibited β galactosidase activity indicating a senescence phenotype. Moreover, we detected production of the pro-inflammatory cytokine TNF-α in cortical PLIN(+) LLC. Some cortical NeuN(+) neurons, GFAP(+) glia limitans astrocytes, Iba-1(+) microglia and S100β(+) ependymal cells expressed PLIN in the aging brain. Our findings suggest that cerebral LLC exhibit distinct cellular phenotypes and may participate in the age-associated neuroinflammatory processes.
Schanz, U; Gmür, J
1992-12-01
The growing number of BMTs has increased interest in safe and standardized in vitro bone marrow processing techniques. We describe our experience with a rapid automated method for the isolation of mononuclear cells (MNC) from large volumes of bone marrow using a Fenwal CS-3000 cell separator without employing density gradient materials. Forty bone marrow harvests with a mean volume of 1650 +/- 307 ml were processed. A mean of 75 +/- 34% (50 percentile range 54-94%) of the original MNCs were recovered in a volume of 200 ml with only 4 +/- 2% of the starting red blood cells (RBC). Removal of granulocytes, immature myeloid precursors and platelets proved to be sufficient to permit safe cryopreservation and successful autologous BMT (n = 25). Allogeneic BMT (n = 14, including three major ABO-incompatible) could be performed without additional manipulation. In both groups of patients timely and stable engraftment comparable to historical controls receiving Ficoll gradient processed autologous (n = 17) or unprocessed allogeneic BMT (n = 54) was observed. Moreover, 70 +/- 14% of the RBC could be recovered from the grafts. They were used for autologous RBC support of donors, rendering unnecessary autologous blood pre-donations.
Kit for the selective labeling of red blood cells in whole blood with .sup.9 TC
Srivastava, Suresh C.; Babich, John W.; Straub, Rita; Richards, Powell
1992-01-01
Disclosed herein are a method and kit for the preparation of .sup.99m Tc labeled red blood cells using whole blood in a closed sterile system containing stannous tin in a form such that it will enter the red blood cells and be available therein for reduction of technetium.
38 CFR 4.117 - Schedule of ratings-hemic and lymphatic systems.
Code of Federal Regulations, 2014 CFR
2014-07-01
... platelets or red cells at least once every six weeks, or; infections recurring at least once every six weeks 100 Requiring transfusion of platelets or red cells at least once every three months, or; infections recurring at least once every three months 60 Requiring transfusion of platelets or red cells at least once...
38 CFR 4.117 - Schedule of ratings-hemic and lymphatic systems.
Code of Federal Regulations, 2012 CFR
2012-07-01
... platelets or red cells at least once every six weeks, or; infections recurring at least once every six weeks 100 Requiring transfusion of platelets or red cells at least once every three months, or; infections recurring at least once every three months 60 Requiring transfusion of platelets or red cells at least once...
38 CFR 4.117 - Schedule of ratings-hemic and lymphatic systems.
Code of Federal Regulations, 2013 CFR
2013-07-01
... platelets or red cells at least once every six weeks, or; infections recurring at least once every six weeks 100 Requiring transfusion of platelets or red cells at least once every three months, or; infections recurring at least once every three months 60 Requiring transfusion of platelets or red cells at least once...
38 CFR 4.117 - Schedule of ratings-hemic and lymphatic systems.
Code of Federal Regulations, 2011 CFR
2011-07-01
... platelets or red cells at least once every six weeks, or; infections recurring at least once every six weeks 100 Requiring transfusion of platelets or red cells at least once every three months, or; infections recurring at least once every three months 60 Requiring transfusion of platelets or red cells at least once...
[Preparation of chicken red blood cells for calibration of flow cytometry].
Yin, Jian; Zhao, Shutao; Wu, Xiaodong; Wang, Ce; Wu, Yunliang
2013-01-01
To prepare stable chicken red blood cells for the calibration of flow cytometry. The traditional isolation method of chicken red blood cells was modified by incorporating gelatin technique, Ca2+-free HBSS treatment and low-speed centrifugation. The effect of fluorescence staining of the cells was improved by the addition of TritonX-100 to enhance the membrane permeability and Rnase enzymes to disintegrate RNA tiles. The modified method was compared with the traditional method for viability of the freshly isolated cells and the DNA content coefficient of variation (CV) of the fixed cells. Chicken red blood cells obtained by the modified method showed a significantly higher viability than those obtained by the traditional method [(98.5∓3.5)% vs (93.5∓2.7)%, P<0.05]. After glutaraldehyde fixation, the isolated cells with the modified method were stable during the 90-day preservation with a significantly lower CV than the cells obtained by the traditional method [(6.0∓0.3)% to 6.2∓0.4% vs (8.6∓0.5)% to (13.1∓1.4)%, P<0.01]. The chicken red blood cells isolated using the modified method can be applicable for calibration of flow cytometry.
NMDA Receptor Activity in Circulating Red Blood Cells: Methods of Detection.
Makhro, Asya; Kaestner, Lars; Bogdanova, Anna
2017-01-01
Abundance and activity of N-methyl-D-aspartate (NMDA) in circulating red blood cells contributes to the maintenance of intracellular Ca 2+ in these cells and, by doing that, controls red cell volume, membrane stability, and O 2 carrying capacity. Detection of the NMDA receptor activity in red blood cells is challenging as the number of its copies is low and shows substantial cell-to-cell heterogeneity. Receptor abundance is reliably assessed using the radiolabeled antagonist ([ 3 H]MK-801) binding technique. Uptake of Ca 2+ following the NMDA receptor activation is detected in cells loaded with Ca 2+ -sensitive fluorescent dye Fluo-4 AM. Both microfluorescence live-cell imaging and flow cytometry may be used for fluorescence intensity detection. Automated patch clamp is currently used for recording of electric currents triggered by the stimulation of the NMDA receptor. These currents are mediated by the Ca 2+ -sensitive K + (Gardos) channels that open upon Ca 2+ uptake via the active NMDA receptor. Furthermore, K + flux through the Gardos channels induced by the NMDA receptor stimulation in red blood cells may be detected using unidirectional K + ( 86 Rb + ) influx.
Prx1 and 3.2 kb Col1a1 promoters target distinct bone cell populations in transgenic mice
Ouyang, Zhufeng; Chen, Zhijun; Ishikawa, Masakazu; Yue, Xiuzhen; Kawanami, Aya; Leahy, Patrick; Greenfield, Edward M.; Murakami, Shunichi
2014-01-01
Bones consist of a number of cell types including osteoblasts and their precursor cells at various stages of differentiation. To analyze cellular organization within the bone, we generated Col1a1CreER-DsRed transgenic mice that express, in osteoblasts, CreER and DsRed under the control of a mouse 3.2 kb Col1a1 promoter. We further crossed Col1a1CreER-DsRed mice with Prx1CreER-GFP mice that express CreER and GFP in osteochondro progenitor cells under the control of a 2.4 kb Prx1 promoter. Since the 3.2 kb Col1a1 promoter becomes active in osteoblasts at early stages of differentiation, and Prx1CreER-GFP-expressing periosteal cells show endogenous Col1a1 expression, we expected to find a cell population in which both the 2.4 kb Prx1 promoter and the 3.2 kb Col1a1 promoter are active. However, our histological and flow cytometric analyses demonstrated that these transgenes are expressed in distinct cell populations. In the periosteum of long bones, Col1a1CreER-DsRed is expressed in the innermost layer directly lining the bone surface, while Prx1CreER-GFP-expressing cells are localized immediately outside of the Col1a1CreER-DsRed-expressing osteoblasts. In the calvaria, Prx1CreER-GFP-expressing cells are also localized in the cranial suture mesenchyme. Our experiments further showed that Col1a1CreER-DsRed-expressing cells lack chondrogenic potential, while the Prx1CreER-GFP-expressing cells show both chondrogenic and osteogenic potential. Our results indicate that Col1a1CreER-DsRed-expressing cells are committed osteoblasts, while Prx1CreER-GFP-expressing cells are osteochondro progenitor cells. The Prx1CreER-GFP and Col1a1CreER-DsRed transgenes will offer novel approaches for analyzing lineage commitment and early stages of osteoblast differentiation under physiologic and pathologic conditions. PMID:24513582
Prolonged red cell storage before transfusion increases extravascular hemolysis
Rapido, Francesca; Brittenham, Gary M.; Bandyopadhyay, Sheila; La Carpia, Francesca; L’Acqua, Camilla; McMahon, Donald J.; Rebbaa, Abdelhadi; Wojczyk, Boguslaw S.; Netterwald, Jane; Wang, Hangli; Schwartz, Joseph; Eisenberger, Andrew; Soffing, Mark; Yeh, Randy; Divgi, Chaitanya; Ginzburg, Yelena Z.; Shaz, Beth H.; Sheth, Sujit; Francis, Richard O.; Spitalnik, Steven L.; Hod, Eldad A.
2016-01-01
BACKGROUND. Some countries have limited the maximum allowable storage duration for red cells to 5 weeks before transfusion. In the US, red blood cells can be stored for up to 6 weeks, but randomized trials have not assessed the effects of this final week of storage on clinical outcomes. METHODS. Sixty healthy adult volunteers were randomized to a single standard, autologous, leukoreduced, packed red cell transfusion after 1, 2, 3, 4, 5, or 6 weeks of storage (n = 10 per group). 51-Chromium posttransfusion red cell recovery studies were performed and laboratory parameters measured before and at defined times after transfusion. RESULTS. Extravascular hemolysis after transfusion progressively increased with increasing storage time (P < 0.001 for linear trend in the AUC of serum indirect bilirubin and iron levels). Longer storage duration was associated with decreasing posttransfusion red cell recovery (P = 0.002), decreasing elevations in hematocrit (P = 0.02), and increasing serum ferritin (P < 0.0001). After 6 weeks of refrigerated storage, transfusion was followed by increases in AUC for serum iron (P < 0.01), transferrin saturation (P < 0.001), and nontransferrin-bound iron (P < 0.001) as compared with transfusion after 1 to 5 weeks of storage. CONCLUSIONS. After 6 weeks of refrigerated storage, transfusion of autologous red cells to healthy human volunteers increased extravascular hemolysis, saturated serum transferrin, and produced circulating nontransferrin-bound iron. These outcomes, associated with increased risks of harm, provide evidence that the maximal allowable red cell storage duration should be reduced to the minimum sustainable by the blood supply, with 35 days as an attainable goal. REGISTRATION. ClinicalTrials.gov NCT02087514. FUNDING. NIH grant HL115557 and UL1 TR000040. PMID:27941245
Cheng, Dong; Zhao, Jiangtao; Jian, Liguo; Ding, Tongbin; Liu, Shichao
2016-09-01
Previous studies found that red cell distribution width was related to adverse cardiovascular events. However, few studies reported the relationship between red cell distribution width and early-stage renal injury in pregnant women with gestational diabetes mellitus. Using a cross-sectional design, 334 pregnant women with gestational diabetes mellitus were enrolled according to the criterion of inclusion and exclusion. Demographic and clinical examination data were collected. Depended on the urine albumin, study population were divided into case group (n = 118) and control group (n = 216). Compared with control group, the case group tend to be higher red cell distribution width level (13.6 ± 0.9 vs.12.5 ± 0.6, p < 0.001). The red cell distribution width was positively associated with albuminuria creatinine ratio (r = 0.567, p < 0.001). Multiple logistic regressions showed that red cell distribution width was still associated with early-stage renal injury after adjusting for many other potential cofounders. Compared with the first quartile, the risk ratio of the second, the third and the fourth quartile were 1.38 (95%CI: 1.06-1.80), 1.57 (95%CI: 1.21-2.97), 2.71 (95%CI: 2.08-3.54), respectively. Besides, systolic blood pressure, estimated glomerular filtration rate, uric acid and blood urea nitrogen were also significantly associated with renal injury in gestational diabetes mellitus patients. The elevated red cell distribution width level might be a predictor of early-stage renal injury in pregnant women with gestational diabetes mellitus. As an easy and routine examination index, red cell distribution width may provide better clinical guidance when combined with other important indices.
Theoretical Study of Electron Transfer Properties of Squaraine Dyes for Dye Sensitized Solar Cell
NASA Astrophysics Data System (ADS)
Juwita, Ratna; Tsai, Hui-Hsu Gavin
2018-01-01
The environmental issues and high cost of Ru create many scientists to explore cheaper and safer sensitizer as alternative for dye sensitized solar cells (DSCs). Dyes play an important role in solar energy conversion efficiency. The squaraine (SQ) dyes has good spectral match with the solar spectra, therefore, SQ dyes have great potential for the applications in DSCs. SQ01_CA is an unsymmetrical SQ dye, reported by Grätzel and colleagues in 2007, featuring a D-π-spacer-A framework and has a carboxylic acid anchoring group. The electron donating ability of indolium in SQ01_CA and SQ01_CAA dyes is relatively weak, better performance may be achieved by introducing an additional donor moiety into indolium [1]. In this study, we investigate six unsymmetrical SQ dyes adsorbed on a (TiO2)38 cluster [2] using density functional theory (DFT) and time-dependent DFT to study electron transfer properties of squaraine dyes on their photophysical. SQ01_CA, WH-SQ01_CA, and WH-SQ02_CA use a carboxylic acid group as its electron acceptor. Furthermore, SQ01_CAA, WH-SQ01_CAA, and WH-SQ02_CAA use a cyanoacrylic acid group as its electron acceptor. WH-SQ01_CA and WH-SQ01_CAA have an alkyl, while WH-SQ02_CA and WH-SQ02_CAA have alkoxyl substituted diarylamines to the indolium donor of sensitizer SQ01_CA. Our calculations show with additional diarylamines in donor tail of WH-SQ02_CAA, the SQ dyes have red-shifted absorption and have slightly larger probability of electron density transferred to TiO2 moiety. Furthermore, an additional -CN group as electron a withdrawing group in the acceptor exhibits red-shifted absorption and enhances the electron density transferred to TiO2 and anchoring moiety after photo-excitation. The tendency of calculated probabilities of electron density being delocalized into TiO2 and driving force for excited-state electron injection of these studied SQ dyes is compatible with their experimentally observed.
Direct Antiglobulin Reaction in ABO-Haemolytic Disease of the Newborn
Romano, E. L.; Hughes-Jones, N. C.; Mollison, P. L.
1973-01-01
The minimum number of IgG anti-A (or anti-B) molecules detectable on A or B red cells by the antiglobulin reaction was found to be the same—that is, about 150 molecules per red cell—with newborn as with adult cells. Furthermore, the ratio of anti-IgG bound to IgG anti-A (or anti-B) molecules was the same whether the anti-A (or anti-B) molecules were present on newborn or on adult cells and was similar to that found for anti-IgG bound to IgG anti-Rh. In 15 infants (11 group A, 4 group B) with haemolytic disease of the newborn due to ABO-incompatibility the amount of anti-A or anti-B on the red cells ranged from 0·25 to 3·5 μg antibody per ml red cells, corresponding to 90-1,320 antibody molecules per cell; only five infants had more than 0·55 μg antibody per ml of red cells. These amounts are far smaller than those found in most moderate or severe cases of Rh-haemolytic disease. It is concluded that the weak direct antiglobulin reactions observed in ABO-haemolytic disease are due simply to the fact that the number of anti-A (or anti-B) molecules on the infant's red cells is at the lower limit of sensitivity of the test. Since ABO-haemolytic disease can be quite a severe process it seems probable that IgG anti-A and anti-B molecules are more effective than anti-Rh molecules in bringing about red cell destruction. PMID:4540300
Stand dynamics of mixed red alder-conifer forests of southeast Alaska.
Robert L. Deal; Paul E. Hennon; Ewa H. Orlikowska; David V. D' Amore
2004-01-01
Stand structure and dynamics were evaluated in mixed red alder (Alnus rubra Bong.) - conifer forests of southeast Alaska. We assessed stand development, tree density, total basal area, diameter distribution of live and dead trees, height distribution of live trees, and mean diameter of all and largest conifers in 40-year-old red alder - conifer...
USDA-ARS?s Scientific Manuscript database
Saltwater sportfishing for red drum, Sciaenops ocellatus, is of immense importance to the recreational saltwater fishing industry from the Gulf of Mexico coastal states through Florida and along the Atlantic seaboard to Maryland and Delaware. Red drum are the second most sought after sportfish in th...
The isolated red spruce communities of Virginia and West Virginia
Harold S. Adams; Steven Stephenson; Adam W. Rollins; Mary Beth Adams
2010-01-01
Quantitative data on the composition and structure of coniferous forests containing red spruce in the mountains of central and southwestern Virginia and eastern central West Virginia, based on sampling carried out in 67 stands during the 1982 to 1984 field seasons, are provided. The average importance value ([relative basal area + relative density/2]) of red spruce was...
A comparison of habitat use and demography of red squirrels at the southern edge of their range
Katherine M. Leonard; John L. Koprowski
2009-01-01
Populations at the edge of their geographic range may demonstrate different population dynamics from central populations. Endangered Mt. Graham red squirrels (Tamiasciurus hudsonicus grahamensis), endemic to southeastern Arizona, represent the southernmost red squirrel population and are found at lower densities than conspecifics in the center of the...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Victoria, E.J.; Pierce, S.W.; Branks, M.J.
1990-01-01
Red blood cell (RBC) autoantibodies from patients with IgG warm-type autoimmune hemolytic anemia were labeled with iodine 125 and their RBC binding behavior characterized. Epitope-bearing RBC membrane polypeptides were identified after autoantibody immunoprecipitation of labeled membranes and immunoblotting. Immunoaffinity isolation of labeled membrane proteins with 12 different IgG hemolytic autoantibodies with protein A-agarose revealed a major polypeptide at Mr 95 to 110 kd, which coelectrophoresed on sodium dodecylsulfate-polyacrylamide gel electrophoresis with a membrane component isolated with sheep IgG anti-band 3. Immunoprecipitation studies with chymotrypsinized RBCs resulted in the recovery of two labeled membrane polypeptides with molecular weights characteristically resulting frommore » the chymotryptic fragmentation of band 3. Immunoblotting with sheep IgG anti-band 3 of the immunoprecipitated polypeptides confirmed that hemolytic autoantibody binding led to recovery of band 3 or its fragments. Two 125I-labeled IgG hemolytic autoantibodies showed binding behavior consistent with epitope localization on band 3. The labeled RBC autoantibodies bound immunospecifically to all types of human RBC tested, including those of rare Rh type (Rh-null, D--) at a site density of approximately 10(6) per RBC. The 125I-IgG in two labeled autoantibodies was 84% and 92% adsorbable by human and higher nonhuman primate RBCs. Antigen-negative animal RBC bound less than 10%, consistent with immunospecific RBC binding. IgG-1 was the major subclass in five autoantibodies tested; one of six fixed complement; and autoantibody IgG appeared polyclonal by isoelectric focusing. We conclude that IgG eluted from RBCs of patients with autoimmune hemolytic anemia consists predominantly of a single totally RBC-adsorbable antibody population that binds to antigenic determinants on band 3.« less
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.
Krol, Marcin; Roterman, Irena; Drozd, Anna; Konieczny, Leszek; Piekarska, Barbara; Rybarska, Janina; Spolnik, Paweł; Stopa, Barbara
2006-02-01
The dye Congo red and related self-assembling compounds were found to stabilize immune complexes by binding to antibodies currently engaged in complexation to antigen. In our simulations, it was shown that the site that becomes accessible for binding the supramolecular dye ligand is located in the V domain, and is normally occupied by the N-terminal polypeptide chain fragment. The binding of the ligand disrupts the beta-structure in the domain, increasing the plasticity of the antigen-binding site. The higher fluctuation of CDR-bearing loops enhances antigen binding, and allows even low-affinity antibodies to be engaged in immune complexes. Experimental observations of the enhancement effect were supported by theoretical studies using L lambda chain (4BJL-PDB identification) and the L chain from the complex of IgM-rheumatoid factor bound to the CH3 domain of the Fc fragment (1ADQ-PDB identification) as the initial structures for theoretical studies of dye-induced changes. Commercial IgM-type rheumatoid factor (human) and sheep red blood cells with coupled IgG (human) were used for experimental tests aimed to reveal the dye-enhancement effect in this system. The specificity of antigen-antibody interaction enhanced by dye binding was studied using rabbit anti-sheep red cell antibodies to agglutinate red cells of different species. Red blood cells of hoofed mammals (horse, goat) showed weak enhancement of agglutination in the presence of Congo red. Neither agglutination nor enhancement were observed in the case of human red cells. The dye-enhancement capability in the SRBC-antiSRBC system was lost after pepsin-digestion of antibodies producing (Fab)2 fragments still agglutinating red cells. Monoclonal (myeloma) IgG, L lambda chain and ovoalbumin failed to agglutinate red cells, as expected, and showed no enhancement effect. This indicates that the enhancement effect is specific.
Kinetic studies of a doubly bound red cell antigen-antibody system.
Oberhardt, B J; Miller, I F
1972-08-01
The Polybrene method for detection of red cell antibodies which utilizes continuous flow equipment was modified so that kinetic studies could be performed on red cell antibodies doubly bound between adjacent red cells. In the anti-Rh(o)-Rh(o) erythrocyte system, deaggregation by temperature was studied over an antibody concentration range of from approximately 1 to 500 antibody molecules per erythrocyte, a residence time range of approximately eightfold, and a temperature range of from 10 to 55 degrees C. The rate of dissociation of antigen-antibody complex, as determined from deaggregation of antibody-dependent red cell aggregates, was found to be of apparent zero order. The apparent activation energy for the antigen-antibody reaction under the experimental conditions was determined and found to be higher than would be expected for singly bound antigen-antibody systems. Possible explanations are considered for these findings in terms of an antigen-antibody bond-breaking model.
Viscoelastic Transient of Confined Red Blood Cells
Prado, Gaël; Farutin, Alexander; Misbah, Chaouqi; Bureau, Lionel
2015-01-01
The unique ability of a red blood cell to flow through extremely small microcapillaries depends on the viscoelastic properties of its membrane. Here, we study in vitro the response time upon flow startup exhibited by red blood cells confined into microchannels. We show that the characteristic transient time depends on the imposed flow strength, and that such a dependence gives access to both the effective viscosity and the elastic modulus controlling the temporal response of red cells. A simple theoretical analysis of our experimental data, validated by numerical simulations, further allows us to compute an estimate for the two-dimensional membrane viscosity of red blood cells, ηmem2D ∼ 10−7 N⋅s⋅m−1. By comparing our results with those from previous studies, we discuss and clarify the origin of the discrepancies found in the literature regarding the determination of ηmem2D, and reconcile seemingly conflicting conclusions from previous works. PMID:25954871
Estrogen receptor is activated by korean red ginseng in vitro but not in vivo.
Shim, Myeong Kuk; Lee, Young Joo
2012-04-01
Ginseng has been used as a traditional medicine for treatment of many diseases and for general health maintenance in people of all ages. Ginseng is also used to ameliorate menopausal systems. We investigated the estrogenic activity of Korean red ginseng (KRG) in a transient transfection system, using estrogen receptor (ER) and estrogen-responsive luciferase plasmids in MCF-7 cells. The extract activated both ERα and ERβ. KRG modulated the mRNA levels of estrogen-responsive genes such as pS2 and ESR1 and decreased the protein level of ERα. In order to examine in vivo estrogenic activity of KRG, sixteen female Sprague-Dawley rats separated into four groups were studied for nine weeks: non-ovariectomized (OVX) rats treated with olive oil, OVX rats treated with olive oil, OVX rats treated with 17-β-estradiol (E2) in olive oil, and OVX rats treated with KRG extract in olive oil. The experiments were repeated for three times and the data of twelve rats were combined. Body weight of OVX rats was greater than that of sham-operated control rats and was decreased by E2 treatment. Uterine weight increased after E2 treatment compared to OVX rats. However, no difference in body or uterine weight was observed with KRG intake. KRG induced reductions in total cholesterol, low density lipoprotein cholesterol/total cholesterol, high density lipoprotein cholesterol/total cholesterol, and low density lipoprotein cholesterol/high density lipoprotein cholesterol, but not to the same degree as did E2 intake. These results show that KRG does contain estrogenic activity as manifested by in vitro study but the activity is not strong enough to elicit physiological responses.
Estrogen Receptor Is Activated by Korean Red Ginseng In Vitro but Not In Vivo
Shim, Myeong Kuk; Lee, Young Joo
2012-01-01
Ginseng has been used as a traditional medicine for treatment of many diseases and for general health maintenance in people of all ages. Ginseng is also used to ameliorate menopausal systems. We investigated the estrogenic activity of Korean red ginseng (KRG) in a transient transfection system, using estrogen receptor (ER) and estrogen-responsive luciferase plasmids in MCF-7 cells. The extract activated both ERα and ERβ. KRG modulated the mRNA levels of estrogen-responsive genes such as pS2 and ESR1 and decreased the protein level of ERα. In order to examine in vivo estrogenic activity of KRG, sixteen female Sprague-Dawley rats separated into four groups were studied for nine weeks: non-ovariectomized (OVX) rats treated with olive oil, OVX rats treated with olive oil, OVX rats treated with 17-β-estradiol (E2) in olive oil, and OVX rats treated with KRG extract in olive oil. The experiments were repeated for three times and the data of twelve rats were combined. Body weight of OVX rats was greater than that of sham-operated control rats and was decreased by E2 treatment. Uterine weight increased after E2 treatment compared to OVX rats. However, no difference in body or uterine weight was observed with KRG intake. KRG induced reductions in total cholesterol, low density lipoprotein cholesterol/total cholesterol, high density lipoprotein cholesterol/total cholesterol, and low density lipoprotein cholesterol/high density lipoprotein cholesterol, but not to the same degree as did E2 intake. These results show that KRG does contain estrogenic activity as manifested by in vitro study but the activity is not strong enough to elicit physiological responses. PMID:23717117
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.
Stabilization of red blood cells by the plasticizer, diethylhexylphthalate.
Horowitz, B; Stryker, M H; Waldman, A A; Woods, K R; Gass, J D; Drago, J
1985-01-01
The red blood cells of blood stored in containers made of polyvinylchloride (PVC) film are osmotically more stable and lose on average about 1/3 less hemoglobin than when blood is stored in another plastic [poly-(ethylene-co-ethyl acrylate); EEA]. The stability of uniform volumes of stored red blood cells varies directly with PVC surface area, whereas changes in EEA surface area have comparatively little or no effect. PVC contains high concentrations of the plasticizer, diethylhexylphthalate (DEHP), known to migrate into blood and to have a high potential for toxicity. To determine if DEHP could be the red cell stabilizing agent in PVC, whole blood was stored in containers made from EEA into which was incorporated varying amounts of DEHP. Incorporation of DEHP into EEA significantly reduced erythrocyte osmotic fragility (p = 0.01). The degree of reduced fragility correlated with the level of DEHP in the cell phase implicating DEHP in PVC containers as the stabilizing agent for red cells.
Effects of Aged Stored Autologous Red Blood Cells on Human Endothelial Function
Kanias, Tamir; Triulzi, Darrel; Donadee, Chenell; Barge, Suchitra; Badlam, Jessica; Jain, Shilpa; Belanger, Andrea M.; Kim-Shapiro, Daniel B.
2015-01-01
Rationale: A major abnormality that characterizes the red cell “storage lesion” is increased hemolysis and reduced red cell lifespan after infusion. Low levels of intravascular hemolysis after transfusion of aged stored red cells disrupt nitric oxide (NO) bioavailabity, via accelerated NO scavenging reaction with cell-free plasma hemoglobin. The degree of intravascular hemolysis post-transfusion and effects on endothelial-dependent vasodilation responses to acetylcholine have not been fully characterized in humans. Objectives: To evaluate the effects of blood aged to the limits of Food and Drug Administration–approved storage time on the human microcirculation and endothelial function. Methods: Eighteen healthy individuals donated 1 U of leukopheresed red cells, divided and autologously transfused into the forearm brachial artery 5 and 42 days after blood donation. Blood samples were obtained from stored blood bag supernatants and the antecubital vein of the infusion arm. Forearm blood flow measurements were performed using strain-gauge plethysmography during transfusion, followed by testing of endothelium-dependent blood flow with increasing doses of intraarterial acetylcholine. Measurements and Main Results: We demonstrate that aged stored blood has higher levels of arginase-1 and cell-free plasma hemoglobin. Compared with 5-day blood, the transfusion of 42-day packed red cells decreases acetylcholine-dependent forearm blood flows. Intravascular venous levels of arginase-1 and cell-free plasma hemoglobin increase immediately after red cell transfusion, with more significant increases observed after infusion of 42-day-old blood. Conclusions: We demonstrate that the transfusion of blood at the limits of Food and Drug Administration–approved storage has a significant effect on the forearm circulation and impairs endothelial function. Clinical trial registered with www.clinicaltrials.gov (NCT 01137656) PMID:26222884
Investigation of membrane mechanics using spring networks: application to red-blood-cell modelling.
Chen, Mingzhu; Boyle, Fergal J
2014-10-01
In recent years a number of red-blood-cell (RBC) models have been proposed using spring networks to represent the RBC membrane. Some results predicted by these models agree well with experimental measurements. However, the suitability of these membrane models has been questioned. The RBC membrane, like a continuum membrane, is mechanically isotropic throughout its surface, but the mechanical properties of a spring network vary on the network surface and change with deformation. In this work spring-network mechanics are investigated in large deformation for the first time via an assessment of the effect of network parameters, i.e. network mesh, spring type and surface constraint. It is found that a spring network is conditionally equivalent to a continuum membrane. In addition, spring networks are employed for RBC modelling to replicate the optical tweezers test. It is found that a spring network is sufficient for modelling the RBC membrane but strain-hardening springs are required. Moreover, the deformation profile of a spring network is presented for the first time via the degree of shear. It is found that spring-network deformation approaches continuous as the mesh density increases. Copyright © 2014 Elsevier B.V. All rights reserved.
Allen L. Lundgren
1981-01-01
Describes an analysis of initial density and subsequent thinning options for red pine (Pinus resinosa Ait.) plantations in the Lake States. Results showed that the initial number of established trees per acres has a major impact on the amount and quality of timber product yields, with 200 trees per acre (500/ha) thinned to 120 square feet of basal area per acre (27.5...
Hemoglobin diffusion and the dynamics of oxygen capture by red blood cells.
Longeville, Stéphane; Stingaciu, Laura-Roxana
2017-09-05
Translational diffusion of macromolecules in cell is generally assumed to be anomalous due high macromolecular crowding of the milieu. Red blood cells are a special case of cells filled quasi exclusively (95% of the dry weight of the cell) with an almost spherical protein: hemoglobin. Hemoglobin diffusion has since a long time been recognized as facilitating the rate of oxygen diffusion through a solution. We address in this paper the question on how hemoglobin diffusion in the red blood cells can help the oxygen capture at the cell level and hence to improve oxygen transport. We report a measurement by neutron spin echo spectroscopy of the diffusion of hemoglobin in solutions with increasing protein concentration. We show that hemoglobin diffusion in solution can be described as Brownian motion up to physiological concentration and that hemoglobin diffusion in the red blood cells and in solutions at similar concentration are the same. Finally, using a simple model and the concentration dependence of the diffusion of the protein reported here, we show that hemoglobin concentration observed in human red blood cells ([Formula: see text]330 g.L -1 ) corresponds to an optimum for oxygen transport for individuals under strong activity.
Hemoglobin diffusion and the dynamics of oxygen capture by red blood cells
Longeville, Stéphane; Stingaciu, Laura-Roxana
2017-09-05
Translational diffusion of macromolecules in cell is generally assumed to be anomalous due high macromolecular crowding of the milieu. Red blood cells are a special case of cells filled quasi exclusively (95% of the dry weight of the cell) with an almost spherical protein: hemoglobin. Hemoglobin diffusion has since a long time been recognized as facilitating the rate of oxygen diffusion through a solution. We address in this paper the question on how hemoglobin diffusion in the red blood cells can help the oxygen capture at the cell level and hence to improve oxygen transport. We report a measurement bymore » neutron spin echo spectroscopy of the diffusion of hemoglobin in solutions with increasing protein concentration. We show that hemoglobin diffusion in solution can be described as Brownian motion up to physiological concentration and that hemoglobin diffusion in the red blood cells and in solutions at similar concentration are the same. Finally, using a simple model and the concentration dependence of the diffusion of the protein reported here, we show that hemoglobin concentration observed in human red blood cells (≃330 g.L -1) corresponds to an optimum for oxygen transport for individuals under strong activity.« less
Hemoglobin diffusion and the dynamics of oxygen capture by red blood cells
DOE Office of Scientific and Technical Information (OSTI.GOV)
Longeville, Stéphane; Stingaciu, Laura-Roxana
Translational diffusion of macromolecules in cell is generally assumed to be anomalous due high macromolecular crowding of the milieu. Red blood cells are a special case of cells filled quasi exclusively (95% of the dry weight of the cell) with an almost spherical protein: hemoglobin. Hemoglobin diffusion has since a long time been recognized as facilitating the rate of oxygen diffusion through a solution. We address in this paper the question on how hemoglobin diffusion in the red blood cells can help the oxygen capture at the cell level and hence to improve oxygen transport. We report a measurement bymore » neutron spin echo spectroscopy of the diffusion of hemoglobin in solutions with increasing protein concentration. We show that hemoglobin diffusion in solution can be described as Brownian motion up to physiological concentration and that hemoglobin diffusion in the red blood cells and in solutions at similar concentration are the same. Finally, using a simple model and the concentration dependence of the diffusion of the protein reported here, we show that hemoglobin concentration observed in human red blood cells (≃330 g.L -1) corresponds to an optimum for oxygen transport for individuals under strong activity.« less
Method and kit for the selective labeling of red blood cells in whole blood with Tc-99m
Srivastava, S.C.; Babich, J.W.; Straub, R.; Richards, P.
1988-07-05
Disclosed herein are a method and kit for the preparation of [sup 99m]Tc labeled red blood cells using whole blood in a closed sterile system containing stannous tin in a form such that it will enter the red blood cells and be available for the reduction of technetium. No Drawings
Method and kit for the selective labeling of red blood cells in whole blood with TC-99M
Srivastava, Suresh C.; Babich, John W.; Straub, Rita; Richards, Powell
1988-01-01
Disclosed herein are a method and kit for the preparation of .sup.99m Tc labeled red blood cells using whole blood in a closed sterile system containing stannous tin in a form such that it will enter the red blood cells and be available therein for the reduction of technetium.
Kit for the selective labeling of red blood cells in whole blood with [sup 99]Tc
Srivastava, S.C.; Babich, J.W.; Straub, R.; Richards, P.
1992-05-26
Disclosed herein are a method and kit for the preparation of [sup 99m]Tc labeled red blood cells using whole blood in a closed sterile system containing stannous tin in a form such that it will enter the red blood cells and be available therein for reduction of technetium. No Drawings
Control of red blood cell mass during spaceflight
NASA Technical Reports Server (NTRS)
Lane, H. W.; Alfrey, C. P.; Driscoll, T. B.; Smith, S. M.; Nyquist, L. E.
1996-01-01
Data are reviewed from twenty-two astronauts from seven space missions in a study of red blood cell mass. The data show that decreased red cell mass in all astronauts exposed to space for more than nine days, although the actual dynamics of mass changes varies with flight duration. Possible mechanisms for these changes, including alterations in erythropoietin levels, are discussed.
1992-05-27
DPG, P50 levels , and the level of residual hemolysis were satisfactory. Our data show that 42-days is the maximum period that red blood cells can...survival value of only 61%, but ATP, DPG, P50 levels and the level of residual hemolysis were satisfactory. Our data show that 42-days is the maximum...collected red blood cells are stored at 4C for less than 2 weeks, the rejuventation process increases the red cell 2,3 DPG level to 250% of normal and the
Aluminum and temperature alteration of cell membrane permeability of Quercus rubra
DOE Office of Scientific and Technical Information (OSTI.GOV)
Junping Chen; Sucoff, E.I.; Stadelmann, E.J.
1991-06-01
Al toxicity is the major factor limiting plant growth in acid soils. This report extends research on Al-induced changes in membrane behavior of intact root cortex cells of Northern red oak (Quercus rubra). Membrane permeability was determined by the plasmometric method for individual intact cells at temperatures from 2 or 4 to 35 C. Al (0.37 millimolar) significantly increased membrane permeability to urea and monoethyl urea and decreased permeability to water. Al significantly altered the activation energy required to transport water (+ 32%), urea (+ 9%), and monoethyl urea ({minus}7%) across cell membranes. Above 9 C, Al increased the lipidmore » partiality of the cell membranes; below 7 C, Al decreased it. Al narrowed by 6 C the temperature range over which plasmolysis occurred without membrane damage. These changes in membrane behavior are explainable if Al reduced membrane lipid fluidity and kink frequency and increases packing density and the occurrence of straight lipid chains.« less
Hemoglobin Aggregation in Single Red Blood Cells of Sickle Cell Anemia
NASA Astrophysics Data System (ADS)
Nishio, Izumi; Tanaka, Toyoichi; Sun, Shao-Tang; Imanishi, Yuri; Tsuyoshi Ohnishi, S.
1983-06-01
A laser light scattering technique was used to observe the extent of hemoglobin aggregation in solitary red blood cells of sickle cell anemia. Hemoglobin aggregation was confirmed in deoxygenated cells. The light scattering technique can also be applied to cytoplasmic studies of any biological cell.
Adams, F.; Bellairs, G.; Bird, A. R.; Oguntibeju, O. O.
2015-01-01
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. PMID:25710038
Ugolini, S; Bruschi, C V
1996-12-01
In the yeast Saccharomyces cerevisiae the ade2, and/or the ade1, mutation in the adenine biosynthetic pathway leads to the accumulation of a cell-limited red pigment, while epistatic mutations in the same pathway, i.e. ade8, preclude this phenomenon, resulting in normal white colonies. The shift in color from red to white (or vice versa) with a combination of appropriate wild-type and mutant alleles of the adenine-pathway genes has been widely utilized as a non-selective phenotype to visualise and quantify the occurrence of various genetic events such as recombination, conversion and aneuploidy. It has provided an invaluable tool for the study of gene dosage and plasmid stability. In competition experiments between disrupted ade2, ade8-18 transformants carrying either a functional or non-functional episomal ADE8 gene, we verified that white ade8 ade2 cells show a remarkable selective advantage over red ade2 cells, with important implications on the use of this assay for the monitoring of genetic events. The accumulation of the red pigment in ade2 cells is likely to be the cause for impaired growth in these cells.
... Blood / What is Blood? WHERE CAN I DONATE? Blood is the red fluid that circulates in our blood vessels, i. ... cells, white blood cells, and platelets. The remainder is a fluid called plasma. Blood cells are produced in bone marrow. Red cells, white cells and platelets are made in ...
Ex-vivo expansion of red blood cells: how real for transfusion in humans?
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.
The role of red alder in riparian forest structure along headwater streams in southeastern Alaska
Orlikowska, E.H.; Deal, R.L.; Hennon, P.E.; Wipfli, M.S.
2004-01-01
We assessed the influence of red alder on tree species composition, stand density, tree size distribution, tree mortality, and potential for producing large conifers, in 38-42 yr old riparian forests along 13 headwater streams in the Maybeso and Harris watersheds on Prince of Wales Island, Alaska. Red alder ranged from 0 to 53% of the total live basal area of the stands. Tree density, basal area of live and dead trees, and mean diameter of live conifers were not significantly related to the percent of alder as a proportion of total stand live basal area within these riparian forests. The mean diameter of the 100 largest conifers per hectare (the largest trees) was similar among different sites and appeared unrelated to the amount of alder in the stands. The mean diameter of dead conifers increased slightly with increasing proportion of red alder. Most dead trees were small and died standing. Red alder was much more concentrated immediately along stream margins (within 0-1 m distance from the stream bank vs. > 1 m). The presence of red alder did not inhibit the production of large-diameter conifers, and both alder and conifers provided small woody debris for fishless headwater streams in southeastern Alaska. Red alder is an important structural component of young-growth riparian stands.
NASA Astrophysics Data System (ADS)
Hernawati; Setiawan, N. A.; Shintawati, R.; Priyandoko, D.
2018-05-01
The purpose of this research was to know the role of red dragon fruit peel powder to total cholesterol, triglyceride, high-density lipoprotein (HDL), low-density lipoprotein (LDL), and weight in the male hyperlipidaemic Balb-C mice (Mus musculus). This study used a completely randomized design (CRD) and four replicates for each dose treatments. Samples were 24 male mice that divided into six groups i.e. positive and negative controls, doses of 50; 100; 150 and 200 mg/kgBW/days red dragon fruit peel powder. Before being given treatment, mice were given feed containing high fat for 20 days until experiencing conditions hyperlipidaemia. The red dragon fruit peel powder was given at oral with used gavage for 30 days. Blood samples were taken from the tail on vena caudalis. Blood lipid samples were analysed at enzymatic with BIOLABO kits. The results of this study indicate that after administration of red dragon fruit peel powder total cholesterol levels, triglycerides and LDL-c decreased, along with increasing doses of red dragon fruit peel powder for 30 days. Furthermore showed that dragon fruit powder can increase HDL-c levels. The conclusion of this research was The red dragon fruit peel powder can improve blood lipid level of male Balb-c mice hyperlipidaemia.
redMaGiC: selecting luminous red galaxies from the DES Science Verification data
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rozo, E.
We introduce redMaGiC, an automated algorithm for selecting Luminous Red Galaxies (LRGs). The algorithm was developed to minimize photometric redshift uncertainties in photometric large-scale structure studies. redMaGiC achieves this by self-training the color-cuts necessary to produce a luminosity-thresholded LRG sam- ple of constant comoving density. Additionally, we demonstrate that redMaGiC photo-zs are very nearly as accurate as the best machine-learning based methods, yet they require minimal spectroscopic training, do not suffer from extrapolation biases, and are very nearly Gaussian. We apply our algorithm to Dark Energy Survey (DES) Science Verification (SV) data to produce a redMaGiC catalog sampling the redshiftmore » range z ϵ [0.2,0.8]. Our fiducial sample has a comoving space density of 10 -3 (h -1Mpc) -3, and a median photo-z bias (z spec z photo) and scatter (σ z=(1 + z)) of 0.005 and 0.017 respectively.The corresponding 5σ outlier fraction is 1.4%. We also test our algorithm with Sloan Digital Sky Survey (SDSS) Data Release 8 (DR8) and Stripe 82 data, and discuss how spectroscopic training can be used to control photo-z biases at the 0.1% level.« less
Tao, Yong; Liu, Jianming; Zhang, Yunhai; Zhang, Meiling; Fang, Junshun; Han, Wei; Zhang, Zhizhong; Liu, Ya; Ding, Jianping; Zhang, Xiaorong
2009-05-01
In evolution, the red panda (Ailurus fulgens) plays a pivotal role in the higher level phylogeny of arctoides carnivore mammals. The red panda inhabits certain Asian countries only and its numbers are decreasing. Therefore, the development of feasible ways to preserve this species is necessary. Genetic resource cryopreservation and somatic cell nuclear transfer (SCNT) have been used extensively to rescue this endangered species. The present study describes the establishment, for the first time, of a red panda ear fibroblast cell line, which was then cryopreserved, thawed and cultured. Through micromanipulation, interspecies embryos were reconstructed using the cryopreserved-thawed fibroblasts of the red panda as the donor and rabbit oocytes as recipients. A total of 194 enucleated rabbit oocytes were reconstructed with red panda ear fibroblasts; enucleated oocytes were activated without fusion as the control. The results show that the fibroblast cell line was established successfully by tissue culture and then cryopreserved in liquid nitrogen. Supplementation with 20% fetal bovine serum and 8% dimethyl sulphoxide in basic medium facilitated the cryopreservation. The interspecies embryos were successfully reconstructed. The cleavage, morulae and blastocyst rates after in vitro culture were 71, 47 and 23% (31/194), respectively. This study indicated that a somatic cell line could be established and cryopreserved from red panda and that rabbit cytoplast supports mitotic cleavage of the red panda karyoplasts and is capable of reprogramming the nucleus to achieve blastocysts.
Mechanisms of red blood cells agglutination in antibody-treated paper.
Jarujamrus, Purim; Tian, Junfei; Li, Xu; Siripinyanond, Atitaya; Shiowatana, Juwadee; Shen, Wei
2012-05-07
Recent reports on using bio-active paper and bio-active thread to determine human blood type have shown a tremendous potential of using these low-cost materials to build bio-sensors for blood diagnosis. In this work we focus on understanding the mechanisms of red blood cell agglutination in the antibody-loaded paper. We semi-quantitatively evaluate the percentage of antibody molecules that are adsorbed on cellulose fibres and can potentially immobilize red blood cells on the fibre surface, and the percentage of the molecules that can desorb from the cellulose fibre surface into the blood sample and cause haemagglutination reaction in the bulk of a blood sample. Our results show that 34 to 42% of antibody molecules in the papers treated with commercial blood grouping antibodies can desorb from the fibre surface. When specific antibody molecules are released into the blood sample via desorption, haemagglutination reaction occurs in the blood sample. The reaction bridges the red cells in the blood sample bulk to the layer of red cells immobilized on the fibre surface by the adsorbed antibody molecules. The desorbed antibody also causes agglutinated lumps of red blood cells to form. These lumps cannot pass through the pores of the filter paper. The immobilization and filtration of agglutinated red cells give reproducible identification of positive haemagglutination reaction. Results from this study provide information for designing new bio-active paper-based devices for human blood typing with improved sensitivity and specificity.
Prevalence of iron deficiency anaemia and thalassaemia trait among undergraduate medical students.
Azma, R Z; Ainoon, O; Azlin, I; Hamenuddin, H; Hadi, N A; Tatt, W K; Syazana, I N; Asmaliza, A M; Das, S; Hamidah, N H
2012-07-01
Anaemia is a global health problem including Malaysia. In adults, anaemia may affect work productivity. Iron deficiency anaemia and thalassaemia are common causes of anaemia in Malaysia. However, there is scarcity of data on national prevalence of iron deficiency anaemia and thalassaemia, especially in young adults. This cross sectional study was performed to determine the prevalence of iron deficiency anaemia and thalassaemia among medical students of Universiti Kebangsaan Malaysia Medical Centre (UKMMC). Blood samples collected in EDTA tubes were analyzed for haemoglobin level and red cell parameters such as MCV, MCH and red cell counts. Samples with abnormal red cell indices were sent for analysis of RBC morphology, iron status, haemoglobin analysis and DNA analysis. A total of 400 samples were available for this study. Fifty-eight (14.5%) students had hypochromic microcytic red cell indices in which 44 (11%) showed thalassaemia red cell indices while 14 (3.5%) had iron deficiency red cell indices which were finally confirmed by serum iron/TIBC analysis. Amongst those suspected to have thalassaemia, 12 (27.3%) were confirmed as alpha thalassaemia trait (αα/--(SEA)), 11 (25%) as Haemoglobin-E trait, 8 (18.2%) as beta thalassaemia trait and 2 (4.5%) as Haemoglobin Constant Spring (αα/α(CS)α). However, eleven students (25%) with thalassaemia red cell indices could not be confirmed with the common thalassaemia primers available, thus causes have yet to be established. Our prevalence of thalassaemia was high and thus we opine that better screening methods should be adopted.
Densities of Agrilus auroguttatus and Other Borers in California and Arizona Oaks
Haavik, Laurel J.; Coleman, Tom W.; Flint, Mary Louise; Venette, Robert C.; Seybold, Steven J.
2014-01-01
We investigated within-tree population density of a new invasive species in southern California, the goldspotted oak borer, Agrilus auroguttatus Schaeffer (Coleoptera: Buprestidae), with respect to host species and the community of other borers present. We measured emergence hole densities of A. auroguttatus and other borers on the lower stem (bole) of naïve oaks at 18 sites in southern California and on co-evolved oaks at seven sites in southeastern Arizona. We sampled recently dead oaks in an effort to quantify the community of primary and secondary borers associated with mortality—species that were likely to interact with A. auroguttatus. Red oaks (Section Lobatae) produced greater densities of A. auroguttatus than white oaks (Section Quercus). On red oaks, A. auroguttatus significantly outnumbered native borers in California (mean ± SE of 9.6 ± 0.7 versus 4.5 ± 0.6 emergence holes per 0.09 m2 of bark surface), yet this was not the case in Arizona (0.9 ± 0.2 versus 1.1 ± 0.2 emergence holes per 0.09 m2). In California, a species that is taxonomically intermediate between red and white oaks, Quercus chrysolepis (Section Protobalanus), exhibited similar A. auroguttatus emergence densities compared with a co-occurring red oak, Q. kelloggii. As an invasive species in California, A. auroguttatus may affect the community of native borers (mainly Buprestidae and Cerambycidae) that feed on the lower boles of oaks, although it remains unclear whether its impact will be positive or negative. PMID:26462589
[Promising technologies of packed red blood cells production and storage].
Maksimov, A G; Golota, A S; Krassiĭ, A B
2013-10-01
The current article is dedicated to promising technologies of packed red blood cells production and storage. The following new technical approaches are presented: (1) erythrocytes storage in strict anaerobic argon-hydrogen environment, (2) lyophilization of erythrocyte suspension by its atomization in nitrogen gas, (3) lyophilization of erythrocytes by directional freezing under the influence of radio frequency radiation, (4) automated pharming of antigen free packed red blood cells from progenitor cell directly at the battlefield.
Forest regeneration composition and development in upland, mixed-oak forests.
Fei, Songlin; Gould, Peter J; Steiner, Kim C; Finley, James C; McDill, Marc E
2005-12-01
Advance regeneration in 52 mature mixed-oak stands was analyzed and described. Red maple (Acer rubrum L.) was the most abundant species in the study area. Among oak (Quercus) species, northern red oak (Q. rubra L.) was the most abundant within the Allegheny Plateau physiographic province, whereas chestnut oak (Q. montana L.) was the most abundant within the Ridge and Valley physiographic province. Sixteen stands, for which data are available through the fourth growing season following harvest, were used to describe stand development. Cumulative height, a composite measure of size and density, was used to describe early stand development. Black gum (Nyssa sylvatica Marsh.) and black birch (Betula lenta L.) had dramatic increases in stand density and cumulative height after overstory removal. Cumulative height of northern red oak and chestnut oak showed a faster positive response to overstory removal than red maple. Oak retained its dominance in cumulative height for at least 4 years after harvest. Red maple nevertheless remained the most abundant tree species after overstory removal. Our results suggest that the principal advantage of red maple regeneration is its ability to accumulate in large numbers prior to harvest.
Nickel, Robert Sheppard; Winkler, Anne M; Horan, John T; Hendrickson, Jeanne E
2016-09-01
Alloimmunization to red blood cell (RBC) antigens after transfusion is well described in patients with sickle cell disease (SCD). We recently demonstrated that leukocyte-reduced RBC transfusions appeared to induce human leukocyte antigen (HLA) antibodies in some children with SCD; now, we hypothesize that residual platelets contained in transfused RBC products may lead to platelet glycoprotein antibody formation. A cross-sectional study was conducted among never pregnant pediatric patients with SCD who either had received many RBC transfusions or had never received any transfusions. Serum was tested for antibodies to platelet-specific glycoproteins using a commercial enzyme immunoassay. Platelet-specific glycoprotein antibodies were found in 12 of 90 patients (13%) in the transfused group versus 5 of 24 patients (21%) in the never transfused group (p = 0.35). The prevalence of antibodies as well as the median standardized optical density for these two groups was not significantly different for any of the studied platelet glycoprotein antigens. There was no association with the presence of platelet-specific glycoprotein antibodies with either RBC or HLA antibodies. Leukocyte-reduced RBC transfusions do not appear to induce platelet-specific glycoprotein antibodies. The positive platelet-specific glycoprotein antibody results from this study may represent platelet autoantibodies, platelet alloantibodies, or false-positive reactions. A better understanding of the immunobiology of patients with SCD at baseline and after blood product exposure may help improve future transfusion and transplantation. © 2016 AABB.
The Effect of Antidepressants on Mesenchymal Stem Cell Differentiation
Kruk, Jeffrey S.; Bermeo, Sandra; Skarratt, Kristen K.; Fuller, Stephen J.
2018-01-01
Background Use of antidepressant medications has been linked to detrimental impacts on bone mineral density and osteoporosis; however, the cellular basis behind these observations remains poorly understood. The effect does not appear to be homogeneous across the whole class of drugs and may be linked to affinity for the serotonin transporter system. In this study, we hypothesized that antidepressants have a class- and dose-dependent effect on mesenchymal stem cell (MSC) differentiation, which may affect bone metabolism. Methods Human MSCs (hMSCs) were committed to differentiate when either adipogenic or osteogenic media was added, supplemented with five increasing concentrations of amitriptyline (0.001–10 µM), venlafaxine (0.01–25 µM), or fluoxetine (0.001–10 µM). Alizarin red staining (mineralization), alkaline phosphatase (osteoblastogenesis), and oil red O (adipogenesis) assays were performed at timed intervals. In addition, cell viability was assessed using a MTT. Results We found that fluoxetine had a significant inhibitory effect on mineralization. Furthermore, adipogenic differentiation of hMSC was affected by the addition of amitriptyline, venlafaxine, and fluoxetine to the media. Finally, none of the tested medications significantly affected cell survival. Conclusions This study showed a divergent effect of three antidepressants on hMSC differentiation, which appears to be independent of class and dose. As fluoxetine and amitriptyline, but not venlafaxine, affected both osteoblastogenesis and adipogenesis, this inhibitory effect could be associated to the high affinity of fluoxetine to the serotonin transporter system. PMID:29564305
Aldridge, Andrew; Kouroupis, Dimitrios; Churchman, Sarah; English, Anne; Ingham, Eileen; Jones, Elena
2013-01-01
Background aims Mesenchymal stromal cells (MSCs) are regenerative and immuno-privileged cells that are used for both tissue regeneration and treatment of severe inflammation-related disease. For quality control of manufactured MSC batches in regard to mature fat cell contamination, a quantitative method for measuring adipogenesis is needed. Methods Four previously proposed methods were validated with the use of bone marrow (BM) MSCs during a 21-day in vitro assay. Oil red staining was scored semiquantitatively; peroxisome proliferator activated receptor-γ and fatty acid binding protein (FABP)4 transcripts were measured by quantitative real-time polymerase chain reaction; FABP4 protein accumulation was evaluated by flow cytometry; and Nile red/4′,6-diamidino-2-phenylindole (DAPI) ratios were measured in fluorescent microplate assay. Skin fibroblasts and MSCs from fat pad, cartilage and umbilical cord were used as controls. Results Oil red staining indicated considerable heterogeneity between BM donors and individual cells within the same culture. FABP4 transcript levels increased 100- to 5000-fold by day 21, with large donor variability observed. Flow cytometry revealed increasing intra-culture heterogeneity over time; more granular cells accumulated more FABP4 protein and Nile red fluorescence compared with less granular cells. Nile red increase in day-21 MSCs was ∼5- and 4-fold, measured by flow cytometry or microplate assay, respectively. MSC proliferation/apoptosis was accounted through the use of Nile red/DAPI ratios; adipogenesis levels in day-21 BM MSCs increased ∼13-fold, with significant correlations with oil red scoring observed for MSC from other sources. Conclusions Flow cytometry permits the study of MSC differentiation at the single-cell level and sorting more and less mature cells from mixed cell populations. The microplate assay with the use of the Nile red/DAPI ratio provides rapid quantitative measurements and could be used as a low-cost, high-throughput method to quality-control MSC batches from different tissue sources. PMID:23260089
Early alterations of red blood cell rheology in critically ill patients.
Reggiori, Giulia; Occhipinti, Giovanna; De Gasperi, Andrea; Vincent, Jean-Louis; Piagnerelli, Michael
2009-12-01
To investigate red blood cell rheology in a large intensive care unit population on admission, and to assess the possible influence of comorbidities on the rheology. : Prospective study. Medico-surgical intensive care unit with 31 beds. All intensive care unit admissions during a 5-month period and 20 healthy volunteers. Blood sampling. A total of 196 intensive care patients (160 without and 36 with sepsis) and 20 healthy volunteers were studied. Red blood cell rheology (deformability and aggregation) was assessed ex vivo using the laser-assisted optical rotational cell analyzer (LORCA; Mechatronics Instruments BV, AN Zwaag, Netherlands) within the first 24 hrs after intensive care unit admission. Red blood cell deformability was determined by the elongation index in relation to the shear stress (0.3 to 50 Pa) applied on the red blood cell membrane surface. Aggregation was assessed by the aggregation index. Septic patients were more likely to have anemia, coagulation abnormalities, and comorbidities than were nonseptic patients. Red blood cell deformability was significantly altered in septic compared to nonseptic patients and volunteers for the majority of shear stress rates studied. The aggregation index was greater in septic patients than in volunteers (67.9% [54.7-73.5] vs. 61.8% [58.2-68.4]; p < .05). Only sepsis and hematologic disease influenced the elongation index (both p < .01). Other comorbidities, like cancer, diabetes mellitus, cirrhosis, and terminal renal failure, had no effect on the elongation index. Aggregation index was related to the degree of organ failure (Sequential Organ Failure Assessment score), the red blood cell count, and fibrinogen concentrations. Early alterations of red blood cell rheology are common in intensive care unit patients, especially in those with sepsis. Comorbidities (other than hematologic diseases) do not significantly influence these abnormalities. These alterations could contribute to the microcirculatory alterations observed in critically ill patients.
Lean red meat consumption and lipid profiles in adolescent girls
Bradlee, M. Loring; Singer, Martha R.; Moore, Lynn L.
2014-01-01
Background Epidemiologic studies of red meat consumption often fail to distinguish between leaner and fattier or processed cuts of meat. Red meat has also been frequently linked with less healthy diet patterns. Data exploring health effects of lean red meat in younger individuals, particularly in the context of a healthy diet, are sparse. This study examined the effects of lean red meat in combination with higher intakes of fruit/non-starchy vegetables on lipid profiles in older adolescent girls. Methods Data from 1,461 girls followed for 10 years starting at 9-10 years of age in the NHLBI Growth and Health Study were used. Diet was assessed using multiple sets of 3-day records collected over eight exam cycles. Outcome measures included fasting levels of low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), non-high-density lipoprotein cholesterol and triglycerides at ages 18-20 years. Results After adjusting for age, race, SES, height, activity level, hours of television/day, and intakes of whole grains and dairy foods using multivariable modeling, girls consuming ≥6 oz lean red meat/wk combined with ≥2 servings of fruit/non-starchy vegetables/day had LDL levels about 6-7 mg/dL lower (p<0.05) than girls with lower intakes of lean red meat and fruit/non-starchy vegetables. In addition, girls with higher intakes of both were 33% less likely (OR=0.67, 95% CI: 0.48-0.94) to have an LDL-C ≥110 mg/dL and 41% less likely (OR=0.59, 95% CI: 0.42, 0.83) to have an elevated LDL:HDL ratio (≥2.2) at the end of adolescence. Conclusion These analyses suggest that lean red meat may be included in a healthy adolescent diet without unfavorable effects on lipid values. PMID:23663235
Red blood cells aligning inside innovative liquid crystal cell
NASA Astrophysics Data System (ADS)
Likhomanova, S. V.; Kamanin, A. A.; Kamanina, N. V.
2017-11-01
Investigation results of red blood cells (human erythrocytes) aligning and fixing inside the liquid crystal (LC) cell have been presented in the present paper. LC cells have been modified through the improved nanostructured relief and LC sensitized with intermolecular charge transfer complex COANP-C70.
Parker, William C; Dey, Daniel C
2008-05-01
A field experiment was established in a second-growth hardwood forest dominated by red oak (Quercus rubra L.) to examine the effects of shelterwood overstory density on leaf gas exchange and seedling water status of planted red oak, naturally regenerated red oak and sugar maple (Acer saccharum Marsh.) seedlings during the first growing season following harvest. Canopy cover of uncut control stands and moderate and light shelterwoods averaged 97, 80 and 49%, respectively. Understory light and vapor pressure deficit (VPD) strongly influenced gas exchange responses to overstory reduction. Increased irradiance beneath the shelterwoods significantly increased net photosynthesis (P(n)) and leaf conductance to water vapor (G(wv)) of red oak and maple seedlings; however, P(n) and G(wv) of planted and naturally regenerated red oak seedlings were two to three times higher than those of sugar maple seedlings in both partial harvest treatments, due in large part to decreased stomatal limitation of gas exchange in red oak as a result of increased VPD in the shelterwoods. In both species, seedling water status was higher in the partial harvest treatments, as reflected by the higher predawn leaf water potential and seedling water-use efficiency in seedlings in shelterwoods than in uncut stands. Within a treatment, planted and natural red oak seedlings exhibited similar leaf gas exchange rates and water status, indicating little adverse physiological effect of transplanting. We conclude that the use of shelterwoods favors photosynthetic potential of red oak over sugar maple, and should improve red oak regeneration in Ontario.