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Seaver S S - - 1992
We are interested in determining the range of variants present in a cell population that can actually be isolated. We have used subcloning and sublining to search for variants with increased antibody stability, increased cell line stability to freezing and defrosting, increased cell population viability, increased antibody production and the ...
Krywolap G N - - 1991
Eubacterium yurii subsp. yurii is an anaerobic, gram-positive rod. On isolation E. yurii forms cellular arrangements resembling test-tube brushes (TTB). Although TTB decreased in size and number on repeated laboratory subculture in enriched media, media poor in available iron enhanced formation of these. Plasmids were not demonstrated, even after chloramphenicol ...
Singh A - - 1991
Erythrocytes with abnormal shapes and deformability reduce cell aggregation and hence sedimentation. It is not known what influence small fractions of these abnormal cells have on the sedimentation behaviour of normal cells. We have used three different methods to alter erythrocyte properties (glutaraldehyde, heat treatment, and metabolic depletion). The admixture ...
Stendig-Lindberg G - - 1991
Twenty apparently healthy Israelis aged 16-52, examined for their history of disease and, carefully screened to exclude concurrent infection or medication, abuse of alcohol or drugs, and pathological findings on routine laboratory estimation, were examined to establish the reference range for the magnesium content of mononuclear cells. The magnesium content ...
Tsiftsoglou A S - - 1991
Simultaneous exposure to 30 microM hemin and 3 x 10(-8) M aclacinomycin (ACL) or mussetamycin for 6 days led to terminal differentiation of K562 cells. The number of hemoglobinized cells and the total hemoglobin content of cells treated with both ACL and hemin exceeded the sum of the corresponding values ...
Williams A R - - 1991
Human erythrocytes resuspended at different hematocrits in autologous plasma at 37 degrees C were exposed to the therapeutic intensities of continuous-wave 0.75-MHz ultrasound in vitro in a rotating tube exposure apparatus designed to maximize the destructive effects of cavitational activity. Provided that large numbers of additional gas bubbles had not ...
Orringer E P - - 1991
A rationale for clinical trials of hydroxyurea (HU) treatment in sickle cell disease is that the agent increases red blood cell (RBC) fetal hemoglobin content. However, an additional effect of HU is to raise the mean corpuscular volume (MCV). To investigate the action of HU in a species that makes ...
Van Oss C J - - 1991
It can be shown theoretically and experimentally that in purely aqueous suspension, cells (as well as microsolutes) are excluded by advancing freezing fronts. This puts the cells under considerable osmotic stress and may be considered to be the major source of cell destruction upon freezing. It is also shown theoretically ...
Tapsall J W - - 1991
The in vitro and cytolytic properties of the hemolysin of group B streptococcus (GBS) were investigated using sheep erythrocytes and McCoy cells adapted for growth in a serum-deficient medium. The relationship between the hemolysin, various carrier molecules and phospholipids was examined. Starch-based carriers interfered with the inhibitory activity of phospholipids ...
Kaul D K - - 1991
To understand the relationship between deoxygenation rate, rheologic behavior, and red blood cell (RBC) morphologic characteristics of blood in sickle (SS) cell anemia, washed oxy SS RBC suspensions (hematocrit, 40%) were subjected to relatively fast and gradual deoxygenation procedures. Relatively fast deoxygenation resulted in 50% decline in percent hemoglobin oxygen ...
Ishihara K - - 1991
Cultured cells derived from hamster insulinoma (In-111 R1 cells) were placed in 1.4 M dimethyl sulfoxide (Me2SO)-containing RPMI 1640 at 20 degrees C for 20 min. They were frozen to -40 degrees C at a cooling rate of 1.0 or 0.5 degrees C/min, subsequently to -80 degrees C at 3 ...
Strauss G H - - 1991
To eliminate between-tests error in longitudinal human studies, for specimen sharing, convenient scheduling, etc., it is necessary for us to freeze leukocytes as well as non-transformed, continuous T lymphocyte (CTL) lines. Two commonly used cryopreservation methods were compared in terms of efficacy. Isolated peripheral blood mononuclear cells and CTLs were ...
Wiebe J P - - 1991
The effect of glycerol on proliferation of BHK, CHO, HBL, MCF-7, and human glioma cells was studied. Cell proliferation was significantly decreased in all the cell lines at glycerol concentrations of 2-4% in the culture medium. The inhibition was dose-dependent, complete suppression of proliferation occurring at a glycerol concentration of ...
Sharma M L - - 1991
In acute hemolytic anaemia of calves induced with phenylhydrazine-hydrochloride, accentuated degenerative changes in circulating erythrocytes occurred on the 5th d post-injection. Marked anisocytosis and poikilocytosis were observed. Crenated cells, acanthocytes (star-shaped cells), dacrocytes (tear drop cells), bite cells, and schistocytes predominated. Heinz bodies were the cytoplasmic hallmark of hemolytic anaemia. ...
Mbassa G K - - 1991
The morphology of the erythrocyte cell series was investigated in external jugular vein blood samples from Dwarf and Danish Landrace goats aged from one day to 12 months. Three erythrocytic cell types were observed in neonates after supravital staining with new methylene blue. The first type were macrocytes which were ...
Hijiya N - - 1991
The effect of varying osmolarities (0.6% to 1.5% NaCl solutions, 213 to 492 mOsm/kg H2O) on the morphology of deoxygenated sickle cells was studied quantitatively with a computer-assisted image analysis system. Discocyte-rich, less dense fractions of sickle cells (density less than or equal to 1.11) were suspended in buffered NaCl ...
Eluwa E O - - 1990
The activity level of acetylcholinesterase in the erythrocytes of 32 patients homozygous for sickle cell anemia was determined and compared with that of normal AA controls as well as with that of AS individuals. Acetylcholinesterase activity was markedly higher in erythrocyte membrane from SS individuals than in those from AS ...
Mackie L H - - 1990
With the use of micromanipulation techniques, the shear modulus or "rigidity" mu, the recovery time tc, and the unfolding time tf for individual sickle cells have been measured at different oxygen tensions, temperatures, and cell densities. In these experiments, the partial pressure of oxygen was varied from 156 to 40 ...
Nordby A - - 1990
Radiographic iodine-containing contrast media (meglumine calcium metrizoate, iohexol and meglumine sodium ioxaglate) were injected intravenously in rats. At various intervals after exposure, in situ cryofixation of kidneys was performed. Thin, freeze-dried cryosections were examined by electron microscopy and X-ray microanalysis. In endothelial cells, erythrocytes and tubular cells high dry weight ...
Ronot X - - 1990
A previous study reported that sperm mitochondrial activity and sperm motility can be evaluated by combined flow and image cytometry, suggesting their potential interest in fertility clinical applications and for studying the effect of physical and chemical agents that modify sperm motility and/or metabolism. This paper focuses on the effect ...
Steinfeld R C - - 1990
Treatment with adriamycin for 8-14 h irreversibly induces K562 human erythroleukemic cells to synthesize hemoglobin. With 16-h exposure, this effect is maximal at concentrations between 180 and 400 nM, yielding 70%-90% benzidine-positive (B+) cells and 24 pg/cell hemoglobin 4 days after the beginning of adriamycin treatment. This induction is accompanied ...
Ortiz O E - - 1990
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 ...
Arumanayagam M - - 1990
The sodium pump activity of erythrocytes is inhibited in hyperthyroidism, whereas in all other cells it is increased. To examine the possibility that thyroid hormones cause an accelerated loss of membrane proteins during in vivo aging, we determined the number of ouabain-binding sites (OBS) in young and old erythrocytes from ...
Tanino K - - 1990
Changes in water content and dry weight were determined in control cells and those induced to cold harden in response to abscisic acid (ABA) treatment (7.5 x 10(-5) molar). Bromegrass (Bromus inermis Leyss cv Manchar) cells grown in suspension culture at room temperature (23 degrees C) for 7 days acclimated ...
DeLoach J R - - 1990
Carrier erythrocytes were prepared to encapsulate L-asparaginase by a hypotonic dialysis process. Dogs received either intravenous or intraperitoneal injections of cells containing both L-asparaginase and the marker [3H]inulin. The route of administration had no effect on the circulating survival of carrier erythrocytes. For enzyme therapy, intraperitoneal injection of a large ...
Horiuchi K - - 1990
An automated image analysis system was used to characterize the morphology of sickle cells under hypoxic conditions. Images observed by light microscopy were transferred to the image analysis system and were processed to binary (black and white) images, and were then analyzed by area, perimeter, and shape. A circular shape ...
Van Dyke D C - - 1990
Cell therapy, the administration of freeze-dried or lyophilized cells derived from fetal tissue of animals, has been suggested and accepted by some parents as a treatment for Down syndrome. Such therapy regimens have been purported to ameliorate dysmorphic features and to result in improvement in IQ, motor skills, social behavior, ...
Eijking E P - - 1990
Recently a Micro Transmission Cell has been developed based on spectrophotometry for in vivo monitoring of SaO2 together with Hb. A study in pigs was performed to compare the cell with standard methods for measuring SaO2, Hb and Ht. The results show that the cell is capable of following the ...
Hopkinson D A - - 1990
Two distinct pyrimidine 5'-nucleotidases (UMPH-1 and UMPH-2) have previously been detected in human erythrocytes; UMPH-1 is deficient in a haemolytic anaemia, while UMPH-2 is unaffected. Only the erythrocyte shows pathological effects in this disorder. Here we have studied lymphoblastoid cell lines from control and UMPH-1 deficient patients to determine whether ...
Chiu D - - 1990
Because peroxidative damage to red cell membranes may contribute to the pathophysiology of sickle cell disease, deficiency of fat- and water-soluble antioxidants could be a determinant in the pathogenesis of this disease. We have previously reported a deficiency of vitamin E in sickle cell disease. The present study was undertaken ...
Hernandez-Ledezma J J - - 1989
The objective of this study was to compare iso-osmolar concentrations (1.5 M) of 1,2-propanediol, glycerol, dimethylsulphoxide and a combination of 1 M propanediol + 0.5M glycerol (PDGLY) as cryoprotectants for murine ovulated oocytes and one-cell embryos. A higher (P < 0.01) percentage of one-cell embryos developed to the two-cell stage ...
Harder S R - - 1989
In this paper we describe an anaerobic titrator made virtually from glass with a small amount of high vacuum epoxy mounted directly to a quartz EPR tube. A complete titration may be carried out with as little as 600 microliters of sample. This cell features the anaerobic manipulation of an ...
Balapure A K - - 1989
A cryostorage procedure was developed to provide ovine luteal cells throughout the period of seasonal anestrus. Corpora lutea obtained from midluteal phase, superovulated ewes were dispersed enzymatically. Some dispersed cells were fractionated into subpopulations by elutriation. Dimethylsulfoxide (7.5% final concentration) in Hanks' buffered saline was added to cells at 4 ...
Nakashima K - - 1989
Erythrocytes were fractionated, by centrifugation, on the basis of cell density, which is proportional to cell age. Glycated hemoglobin (Hb A1c) in the fractionated cells was measured and compared with the Hb A1c in whole blood and with the fructosamine concentrations in plasma of normal and diabetic subjects. In normal ...
Schmalzer E A - - 1989
The rheologic behavior of sickle cells was evaluated with a constant flow filtration system at 37 degrees C by using filters with pores of 4.8 microns diameter. Analysis of the shape of the pressure-time curves suggested that sickle cells were subdivided into two discrete subpopulations: (1) relatively deformable cells and ...
Keidan A J - - 1989
Erythrocytes from 12 patients with homozygous sickle cell disease in the steady state were fractionated on a Percoll-Stractan density gradient. Erythrocyte deformability was measured by initial-flow-rate filtration through pores of 5 microns diameter and erythrocyte polymer content was calculated as a function of oxygen saturation. Density fractionated sub-populations of sickle ...
Frame J N - - 1989
The aim of this study was to compare the extent of in vitro T cell depletion and recovery of hematopoietic progenitor cells achieved with five methods of T cell depletion. Bone marrow samples from the same source were treated with monoclonal antibody Campath-1 (CP1) and human complement, XomaZyme-H65 (anti-T cell ...
Fabry M E - - 1989
We have developed an animal model to elucidate the acute effects of perfusion abnormalities on muscle metabolism induced by different density-defined classes of erythrocytes isolated from sickle cell anemia patients. Technetium-99m (99mTc)-labeled, saline-washed normal (AA), homozygous sickle (SS), or high-density SS (SS4) erythrocytes were injected into the femoral artery of ...
Ito Y - - 1989
In order to clarify the utility of resealed erythrocytes as a cell carrier of insulin the freezing stabilities of loaded cells encapsulating two different amounts of insulin (about 0.1 and 7.0 IU/ml of packed cells) were investigated in an anti-freezing reagent containing a high concentration of glycerol at -80 degrees ...
Tarczynski M C - - 1989
The ribulose 1,5-bisphosphate carboxylase/oxygenase (Rubisco) contents of guard cells and other cells of Vicia faba L. leaflet were determined. To prevent proteolysis, proteins of frozen protoplast preparations or of cells excised from freeze-dried leaf were extracted directly in a sodium-dodecyl-sulfate-containing solution, which was heated immediately after sample addition. Protein profiles ...
Mazur P - - 1989
The cause of slow freezing injury and the basis of the protection by solutes like glycerol are subjects of debate. During slow freezing, cells are sequestered in unfrozen channels between ice crystals that grow by removing pure water from the channels. As a consequence, the solute concentration in the channels ...
Franco R S - - 1989
Important properties of red blood cells (RBCs), including oxygen affinity and intracellular hemoglobin concentration, may be modified by means of an osmotic pulse. The pulse is developed by rapid dilution of a suspension of RBCs to which dimethylsulfoxide has been added. The nature and degree of RBC modification is dependent ...
Matányi S - - 1989
Cryotherapy of the uterine cervix can produce tissue damage of various depths. It is very important to be familiar with the extent of tissue damage in standardizing the treatment and assessing its effect. In the present work nonspecific esterase reaction was applied for the early study of tissue damage. It ...
Kraiem A - - 1989
A rigidity index (RI) related to red blood cell deformability was measured by using the hemorheometre. The RI for 13 patients homozygous for sickle cell disease was 109 +/- 44 at 37 degrees C and at atmospheric pO2. The filtration time curve as a function of pO2 is biphasic for ...
Clark M R - - 1989
A prominent characteristic of sickle cells is the presence of a subpopulation of severely dehydrated cells. Apart from its effect on the rate and extent of Hb S polymerization at low oxygen tension, dehydration has adverse effects on deformability of oxygenated sickle cells. In general, the degree of deformability defect ...
Miyoshi K - - 1988
Fetal hemoglobin (HbF) levels determined in healthy Japanese adults ranged from 0.3% to 16.0% as F cells and 0.17% to 2.28% as HbF content, which were the same as those obtained in other countries. The frequency distribution of 300 healthy adults with various numbers of F cells consisted statistically of ...
Silani V - - 1988
A human neuronal cell freezing technique has been developed. The results indicate that human fetal neuronal cells can be frozen with 7%-10% dimethyl sulfoxide (DMSO) as cryoprotectant. The survival of isolated thawed cells has been evaluated in culture. Cells have been frozen at -196 degrees C for 370 days without ...
Bustamante J O - - 1988
Single cells were isolated from human heart specimens and preserved at -56 degrees C in a cryoprotecting solution containing dimethyl sulfoxide. The cells were reanimated by rapid thawing and the properties of the cells were evaluated in a physiological solution. The reanimated cells showed morphological and physiological properties similar to ...
Takahashi T - - 1988
To elucidate the means by which polymer solutions protect cells from freezing injury, we cooled human monocytes to -80 degrees C or below in the presence of various polymers. Differential scanning calorimetric studies showed that those polymers which protect cells best have a limiting glass transition temperature (T'g) of approximately ...
Zierold K - - 1988
Various electron microscopical preparation techniques are compared with regard to the preservation of the intracellular element distribution as determined by X-ray microanalysis in scanning and scanning transmission electron microscopy. By use of chemical agents for fixation and dehydration ions are redistributed and washed out. This is also true for freeze-substitution. ...
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