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Göttlinger C - - 1986
We have built a cooling device for cell suspensions in flow cytometry that makes use of the Peltier effect (Barnard RD, Thermo electricity in Metals and Alloys, Taylor and Francis, London; Siemens-Z 34:383-88, 1963). The prototype described here is used for cooling collection tubes during long-duration cell sorting and is ...
Brugnara C - - 1986
The pathophysiological events in sickle cell disease are critically dependent on the intracellular concentration of hemoglobin S, which varies inversely with cell cation and water content. Erythrocytes of SS homozygotes exposed to oxygen or carbon monoxide decrease their potassium and water content through a pathway for potassium transport that is ...
Ohnishi S T - - 1986
When red blood cells from sickle-cell patients were exposed to repeated cycles of deoxygenation and reoxygenation (one cycle was 5 min), dehydration of the cells was observed after several cycles of the sickling-desickling process. These dehydrated cells still maintained a biconcave form after 1 h of such cycling, but they ...
Kruuv J - - 1986
When multicellular spheroids, which simulate small bits of tissue, are exposed to a freeze-thaw (FT) cycle, the survival of the individual cells in the spheroid is higher if the cells of the spheroid are trypsinized and plated as single cells immediately after thawing than if the spheroid is allowed to ...
Lammers M - - 1986
Yeast cells permeabilized by freeze-thaw cycles in a sorbitol-containing medium provide an experimentally favorable system for the study of ribonucleotide reduction in a small number of cells or in mutant strains. Ribonucleotide reductase activities determined in such cells are about twice those found in cell extracts but properties of the ...
Mori Y - - 1986
The effect of freeze-thawing on the yeast respiratory system was studied at rapid rates of cooling. Freezing of whole cells with liquid nitrogen induced decrease of respiratory activity to under 20% of that of original cells. Mitochondria harvested from freeze-thawed cells have markedly decreased succinate oxidizing activity. Activity of succinate ...
Tomkins D J - - 1986
In monitoring occupational populations with the human lymphocyte cytogenetic test, it is not always possible to collect and process matched samples on the same day, even though this would be desirable to control for technical variables. The effects of holding samples for 24 hours at 4 degrees C and 22 ...
Eichler H G - - 1986
Encapsulation of heparin into resealed carrier erythrocytes may be useful in the prevention of thromboembolism because heparin may be released locally during retraction of fresh thrombi. Heparin encapsulation in human and canine erythrocytes was achieved by hypo-osmotic dialysis with 44% and 36% encapsulation, respectively. Encapsulated heparin did not leak from ...
McColm A A - - 1986
Several cryoprotectants were compared using two different cooling procedures for the cryopreservation of both normal and Plasmodium yoelii-infected mouse erythrocytes. Fast cooling to -196 degrees C by direct plunge into liquid nitrogen followed by rapid thawing in a 37 degree C water bath protected uninfected and parasitized erythrocytes against freeze-thaw ...
Ohnishi S T - - 1986
Nitrendipine, nifedipine and verapamil inhibit the in vitro formation of irreversibly sickled cells. Using a method of forming both dehydrated cells and irreversibly sickled cells in vitro by repeated cycles of sickling and unsickling, the effects of several drugs in inhibiting the formation of these cells were studied. Drugs known ...
Sutera S P - - 1986
Adequate erythrocyte deformability is crucial to microvascular function. In sickle cell anemia, a significant fraction of the circulating red cells lose deformability and assume highly abnormal shapes when exposed to low plasma oxygen tension (PO2). The loss of deformability is believed to induce blockage of flow in capillaries with consequent ...
Baudin V - - 1986
Factors that modify the intraerythrocytic concentration of hemoglobin S may influence the clinical expression of the disease. Using the phthalate ester method, the red blood cell density has been studied as a function of the mean corpuscular hemoglobin concentration. Four parameters have been used to compare the density distribution of ...
Furukawa K - - 1985
The differential reactivity of four mouse monoclonal antibodies (AbCB, AbHT29-36, AbM2, and AbS12) and Dolichos biflorus lectin with A1 and A2 erythrocytes was analyzed. Only AbS12 and D. biflorus lectin were able to preferentially agglutinate A1 erythrocytes. AbS12 is known to react only with short chain, unbranched structures (such as ...
Tanishima K - - 1985
Following the observation of two fraternal patients without neurologic symptoms, but with hereditary methemoglobinemia due to cytochrome b5 reductase deficiency in erythrocytic and nonerythrocytic cells, a familial study of their paternal and maternal relatives was undertaken. Ferrihemoglobin reductase activities in erythrocytes from the two patients were found to be impaired, ...
Noe D A - - 1985
A model of red cell hemoglobin concentration has been developed and computer stimulations performed to investigate quantitatively the relationship among the intraindividual heterogeneities of cell hemoglobin content, volume, and hemoglobin concentration. In the model, the cell volume and hemoglobin content frequency distributions and their joint distributions are described by Gaussian ...
Ogiso T - - 1985
The application and usefulness of resealed erythrocyte as a cell carrier of dexamethasone were studied in rabbits. The erythrocytes were loaded with water soluble dexamethasone sodium phosphate by hypotonic dilution and dialysis methods. During in vitro incubation at 37 degrees C, the level of dexamethasone held within the resealed according ...
Mazur P - - 1985
We have shown previously that the survival of human red blood cells during slow freezing at 2% hematocrit is dependent more on the magnitude of the unfrozen fraction than on the salt concentration in that unfrozen fraction. In parallel, first Nei and more recently Pegg and colleagues have shown that ...
Bevington A - - 1985
Orthophosphate (Pi), adenosine 5'-diphosphate (ADP), adenosine 5'-triphosphate (ATP) and 2,3-diphosphoglycerate (2,3-DPG) were measured in the erythrocytes of patients in an intensive care unit. The patients' plasma concentration of Pi varied from 0.1 to 4.2 mmol/l, and the corresponding concentration in erythrocytes varied from 0.1 to 2.0 mmol/litre of cells. Marked ...
Conscience J F - - 1985
A new technique for the cryopreservation of cell lines of hemopoietic origin is described. It uses a combination of 10% polyvinylpyrrolidone or hydroxyethylstarch with 15% glycerol, a slow stepwise addition of the cryoprotectants before freezing, cooling at 4 degrees C/min, rapid rewarming, and a slow step-wise dilution after thawing. This ...
Challa A - - 1985
A technique is described for the determination of orthophosphate (Pi) in human erythrocytes. The advantages of the technique are that it uses whole blood rather than separated erythrocytes, that it avoids major hydrolysis of organic phosphates, that it takes account of incomplete recovery of Pi and that it minimizes the ...
Kaiho S - - 1985
Sensitive and rapid assays, colorimetry and histochemistry, for hemoglobin in erythroid cells are established. The assays are based on pseudoperoxidase activity of hemoglobin using 2,7-diaminofluorene as a hydrogen donor for the peroxidase, instead of benzidine which is widely benzidine which is widely used for the detection of small amounts of ...
Bhandal I S - - 1985
Suspension cultures of carrot (Daucus carota, line C1), tobacco (Nicotiana tabacum, line TX1), and Nicotiana plumbaginifolia (line NP) were frozen under controlled conditions with trehalose as the sole cryoprotectant. Maximal post-thaw viability (71-74%), measured by phenosafranin dye exclusion, was obtained with the C1 cells following a 24hour pretreatment with 5 ...
de Korte D - - 1985
An anion-exchange high-performance liquid chromatography method has been used to quantitate the intracellular purine and pyrimidine nucleotides in extracts of pure lymphocytes, monocytes, neutrophils, eosinophils, erythrocytes, and platelets isolated from the blood of healthy human donors. For accurate and reproducible measurements of the nucleotide profiles in different types of pure ...
Noguchi C T - - 1985
Homozygous alpha-thalassemia has the beneficial effect in sickle cell anemia of reducing the hemolytic severity while changing several other hematological parameters. We examined in detail the cellular basis of some of these hematologic alterations. We find that the broad distribution in erythrocyte density and the large proportion of dense cells ...
Van Noorden C J - - 1985
A cytochemical method for staining glucose-6-phosphate dehydrogenase (G6PD) activity in individual erythrocytes as reported previously has been optimized further by the incorporation of a number of technical improvements. Analysis of the enzyme content in erythrocytes of normal individuals as well as patients suffering from G6PD deficiency in the homozygous and ...
Myhrvold V - - 1985
Human monocytes were isolated from peripheral blood by Lymphoprep density-gradient centrifugation and adherence to fibronectin. The cells were loosened by ethylene-diamino-tetra-acetate (EDTA), frozen by different freezing methods, thawed, washed and compared to unfrozen cells. After freezing, thawing and washing, cell recovery was calculated and found to vary with the freezing ...
Cochran R C - - 1985
Rams representing five breeds were electroejaculated twice weekly, during a three-week collection period. Ejaculates were evaluated for volume and concentration before freezing and for rate of motility and percentages of motile and abnormal cells both before and after freezing. Interactions between breed and collection period were evident (P<0.05) for semen ...
Mohr L R - - 1985
Studies on the cryopreservation of 162 four-cell and eight-cell human embryos indicate that morphological survival and pregnancies can be achieved by specific techniques of freezing and thawing. Survival rates are highest when embryos are cooled at 0.3 degrees C/min to -80 degrees C in the presence of 1.5 M dimethylsulfoxide ...
Williamson J R - - 1985
This study was undertaken to determine whether diabetes alters the viscoelastic properties of erythrocytes. The oldest and youngest 10% fractions of circulating red cells were separated by centrifugation of freshly drawn blood obtained from ten diabetics with disease of one to 20 years' duration and from an equal number of ...
Kon K - - 1985
The electron paramagnetic resonance (EPR) spin label method was used to investigate the effect of varying hematocrit on the deformation and orientation behavior of erythrocytes in shear flow. The relative EPR spectral change due to flow, which we use as a measure of the average deformation and orientation of erythrocytes, ...
PÄ•knicová J - - 1985
Hybridoma technology requires freezing of parental myeloma cells, continuous freezing and thawing of clones and stable hybridoma cells. A modification of the method of two-step freezing is described. The cryoprotective agent (5% dimethyl sulphoxide) is added to the cells at room temperature for 10 min. Cells are then transferred directly ...
Scher W - - 1985
Several protease preparations of varied specificity increased hemoglobin levels in K562 cells. These are the first enzymes shown to stimulate this process in these cells. Hemin, at a concentration at which it did not act as a potent inducer of hemoglobin production, was found to synergistically stimulate induction by proteases. ...
Tatsumi N - - 1985
The expansibility under hypotonic condition and the susceptibility to saponin under hypotonic and deoxygenated conditions were determined. The experiments were carried out using a conventional blood cell counter and comparable volume changes were displayed on a chart as a graphic presentation. The sickle cells showed low expansibility and strong resistance ...
Halperin G - - 1984
Implantation of hydrocarbon chains on beaded agarose results in column materials capable of adsorbing erythrocytes or lymphocytes from various sources. In a homologous series of such columns, identical in all structural respects (ligand density, charge density and ultrastructure) except for the length of their hydrocarbon chains, the capacity to adsorb ...
Moore C J - - 1984
Primary hepatocyte cultures from six human donors were established and their abilities to metabolize the polycyclic aromatic hydrocarbon carcinogen benzo[a]pyrene (B[a]P) were examined. Cells from each donor were plated at similar densities (1 X 10(7) cells/100 mm dish). All cultures metabolized B[a]P to a significant extent (24-35 nmol in 24 ...
Mazur P - - 1984
Cells can endure storage at low temperatures such as--196 degrees C for centuries. The challenge is to determine how they can survive both the cooling to such temperatures and the subsequent return to physiological conditions. A major factor is whether they freeze intracellularly. They do so if cooling is too ...
Fabry M E - - 1984
The etiopathologic basis of painful crisis in sickle cell anemia is largely unknown, and no objective criteria for its diagnosis and follow-up exist at present. We have studied 11 patients through 14 painful crises and observed a significant decrease of the densest fraction of red cells in 12 of the ...
Chen T H - - 1984
A procedure for cryogenic storage of alkaloid producing cell lines of periwinkle, Catharanthus roseus (L.) G. Don., has been developed. The procedure differs from established cryopreservation protocols in several aspects. Specifically, 4-day-old suspension subcultures of three cell lines were precultured in nutrient media supplemented with 1 molar sorbitol for 6 ...
Ofer S - - 1984
Diffusive motions of the magnetosomes (enveloped Fe3O4 particles) in the magnetotactic bacterium Aquaspirillum magnetotacticum result in a very broad-line Mössbauer spectrum (T approximately 100 mm/s) above freezing temperatures. The line width increases with increasing temperature. The data are analyzed using a bounded diffusion model to yield the rotational and translational ...
Kaku M - - 1984
KMOE -2/05 cells, derived from a patient with acute erythremia, became benzidine-positive after the addition of cytosine arabinoside (CA). Radioimmunoassays using antihuman hemoglobin antibodies revealed an elevated amount of hemoglobin in the CA-exposed cells over that in the control cells (without CA). Isoelectric focusing of the CA-exposed cell lysate formed ...
Takayama Y - - 1984
The number of sodium pump units of erythrocytes measured with ouabain binding assay was significantly lower in 17 patients with essential hypertension (0.538 +/- 0.020 pmol/10(9) cells) than in 13 normotensive controls (0.673 +/- 0.031 pmol/10(9) cells) (p less than 0.01) and it was inversely correlated with erythrocyte sodium concentration ...
Guis M S - - 1984
The effect of dimethyl adipimidate (DMA), an amino-reactive crosslinking reagent with demonstrated antisickling properties in vitro, on the survival of 51Cr-labeled autologous sickle cells was evaluated in five adult males with sickle cell anemia. The survival of cells pretreated with 5 mmol/L DMA (pH 7.4), normal (t1/2 28-33 days) in ...
Joseph-Silverstein J - - 1984
Marginal bands (MBs) of microtubules are believed to function during morphogenesis of nonmammalian vertebrate erythrocytes, but there has been little evidence favoring a continuing role in mature cells. To test MB function, we prepared dogfish erythrocytes with and without MBs at the same temperature by (a) stabilization of the normally ...
Mooradian A D - - 1984
Red blood cell (RBC) and polymorphonuclear white blood cell (WBC) calmodulin levels were measured in 25 uremic patients on regular hemodialysis. Uremic patients had significantly higher RBC [11.45 +/- 0.66 (+/-SE) fg/cell] and WBC (590.5 +/- 110 fg/cell) calmodulin levels than normal subjects (8.62 +/- 0.37 and 130 +/- 30 ...
Bell G A - - 1984
The condition of freeze-fixed mitral cells from the main olfactory bulb of the rat brain was found to depend on the rat at which the tissue is frozen: at very slow rates, mitral cells swell and rupture; at faster rates, cell integrity is preserved. Cooling the tissue to just above ...
Crist D K - - 1984
Three Rhizobium japonicum strains and two slow-growing cowpea-type Rhizobium strains were found to remain viable and able to rapidly modulate their respective hosts after being stored in purified water at ambient temperatures for periods of 1 year and longer. Three fast-growing Rhizobium species did not remain viable under the same ...
Weibull C - - 1984
Cells of the bacterium Acholeplasma laidlawii were rapidly frozen against a copper block cooled by liquid helium. The frozen cells were transferred to liquid nitrogen and subsequently to acetone or methanol at 183 K. After 24 h the cells were infiltrated at 203 K with a non-polar methacrylate resin of ...
Boxman A W - - 1984
Membrane potentials of yeast cells, Saccharomyces cerevisiae, calculated from the equilibrium distribution of tetraphenylphosphonium (TPP) between cell-water and medium should be corrected for a contribution due to binding of TPP to intracellular constituents. The magnitude of this correction depends upon the way in which it is determined. In cells permeabilized ...
Wetterstroem N - - 1984
To assess the possibility that the membrane lesion seen in sickle cells involves oxidant damage, we investigated the relationship between irreversibly sickled cells and glutathione levels and Heinz body production. We found that the mean level of red cell glutathione, whether expressed as micromoles per gram of hemoglobin or micromoles ...
Plattner H - - 1984
From a total number of approximately 1100-1300 secretory organelles ("trichocysts") in a Paramecium tetraurelia cell, approximately 90% are docked to the cell membrane. Approximately 90% of this subpopulation can be discharged from the cells within seconds, when exposed to the novel trigger agent aminoethyldextran (AED) at a concentration of 10(-6) ...
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