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Takamatsu H - - 1999
Most of the researchers in the field of cryobiology believe that the mechanism of damage during freezing with low cooling rates is chemical and related to the hypertonicity of the extracellular solution. However, there is some evidence to indicate that cells may be destroyed during freezing also by compression between ...
Marcus S J - - 1999
Fetal hemoglobin (HbF) is an important determinant in the clinical severity of patients with sickle cell disease. The physiologic decline in HbF parameters in a cohort of infants with sickle cell disease was investigated. The percent HbF and F cells were quantitated, and the HbF per F cell was then ...
Pasch J - - 1999
The cryopreservation of cells in tissues is one of the major challenges in current cryobiology, especially with regard to the progressively increasing field of tissue engineering. It is very questionable whether protocols which were developed for the cryopreservation of isolated cells are also applicable for cells in more complex structures, ...
Guillouzo A - - 1999
Cryopreservation in liquid nitrogen is presently the only way for long-term storage of isolated hepatocytes. Freeze-thaw conditions are not well defined yet; the most critical parameters appear to be the choice of the cryoprotectant, composition of the freezing medium, and cooling and thawing rates. Comparable results have been obtained with ...
Matsunaga T - - 1999
Twenty four strains out of 191 marine microalgal strains exhibited cadmium (Cd) resistance. They were tested for their Cd removal ability in growth media containing 50 microM Cd. Six strains out of 19 green algae and one out of five cyanobacteria removed more than 10% of total Cd from the ...
Azhakanandam K - - 1999
Supplementation of semi-solid R2 culture medium with a commercial bovine haemoglobin (Hb) solution (Erythrogen) at 1:50-1:500 (v:v), had beneficial effects on the growth, following cryopreservation, of cells of the Indica rice, Oryza sativa cv. Pusa Basmati 1. The mean absorbance, as assessed by triphenyl tetrazolium chloride reduction, of rice cells ...
Djurić D - - 1999
A freezing device for cryopreservation of blood mononuclear cells has been developed. The device is microcontroller operated, allowing cell freezing by a fully automatic, unattended process. To ensure optimum preservation, the temperature in the cell suspension uniformly decreases from room temperature to -100 degrees C and then the samples are ...
Clarke DM - - 1999
Cryosurgery is now being used to eradicate a variety of tumors, including those that are found in the kidney. Because it is well known that cancer treatments are often most effective when combined with adjunctive therapies, we developed a model kidney cell culture system to determine: (1) if 5-fluorouracil (5-FU), ...
Borhan S - - 1999
A young woman in her 20s with a lifelong history of sickle-cell disease presents with sickle-cell crisis while in active labor. After delivery of the neonate via cesarean section, her fever spikes to nearly 106 F (41.1 C) and stays there. Clinicians are invited to comment on this case in ...
Gilles R - - 1999
(1) Compensatory organic osmolytes are stabilizers of macromolecular structures. During acclimation to dehydration or high salinity, they accumulate in cells and effectively protect them against disruption that might otherwise result from increased inorganic ion concentrations. (2) Circular and electric dichroism, analysis of the kinetics of digestion by micrococcal nuclease, and ...
Lisovskaya I L - - 1999
We have previously proposed the osmofiltration method based on a modified Hanss hemorheometer to analyze distributions of erythrocytes in their ability to pass through membrane filters with 3 microns pores. Upon decrease in medium osmolality (u) the erythrocyte volume increases. When cell volume becomes V = Vcr at u = ...
Poirier I - - 1999
The effects of rehydration kinetics and temperature on the viability of Saccharomyces cerevisiae dehydrated by drying were studied. During rehydration, a water activity range of 0.117-0.455 must be crossed slowly in order to maintain cell viability. If this range is crossed rapidly, cell viability can be preserved if rehydration takes ...
Gayol S - - 1999
Astrocytes were cultured from striatum and neocortex of fetal (embryonic day 90) monkeys (Cebus apella). The cultures grew well, and the cells retained viability after freeze-storage and thawing. The cells displayed depolarized membrane potentials (-19 and -33 mV, for striatal and cortical cells, respectively) and the vast majority of cells ...
Schwartz R S - - 1998
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 ...
Zhang Z - - 1998
A protocol is described for individually collecting two populations of sperm cells, Svn and Sua, from pollen of Plumbago zeylanica. Pollen grains were burst in 10 mM MOPS buffer containing 0.8 M mannitol (pH 4.6). Paired sperm cells released from pollen were separated using a microinjector. Svn and Sua were ...
Gage A A - - 1998
As the modern era of cryosurgery began in the mid 1960s, the basic features of cryosurgical technique were established as rapid freezing, slow thawing, and repetition of the freeze-thaw cycle. Since then, new applications of cryosurgery have caused numerous investigations on the mechanism of injury in cryosurgery with the intent ...
McNiece I K - - 1998
Ex vivo expansion of cord blood (CB) cells requires CD34+ cell selection before expansion to obtain optimal numbers of progenitor cells. As a preliminary step to preclinical development of CB expansion, we have evaluated two clinical scale selection devices, the Isolex 300i (Baxter Healthcare, Immunotherapy Division) and the CliniMACS (Miltenyi ...
Fowler A J - - 1998
This paper reports on the successful recovery of rapidly frozen unprotected erythrocytes by vitrification of the intracellular solution with a laser pulse prior to thawing. Erythrocytes that were frozen at 10,000 degrees C/min exhibited 100% hemolysis when thawed unless they were first irradiated by a 7 ns. laser pulse that ...
Thein S L - - 1998
Hb F and F cell values in normal adults vary considerably with a continuous distribution that is substantially skewed to the right implicating a polygenic influence. The high values of Hb F and F cells are transmitted in the condition referred to as heterocellular hereditary persistence fetal hemoglobin which should ...
Maier-Redelsperger M - - 1998
Production of fetal hemoglobin (Hb F) involves molecular as well as cellular aspects as, among red blood cells, it is restricted to a specific population referred as the F cells. Thus understanding the mechanisms involved in persistence or re-emergence of Hb F production in various inherited or acquired conditions requires ...
De Loecker W - - 1998
Increasing the cell concentration during the cryopreservation of red blood cells (RBC) increased hemolysis. Similarly, increasing the cell concentration during the cryopreservation of hepatocytes reduced both the viability of the cells as assessed by trypan blue exclusion and the metabolic activity of the trypan blue-excluding cells. In both cell types, ...
Neufeld D S - - 1998
Cells in freeze-tolerant tissues must survive substantial shrinkage during exposure to the hyperosmolarity that results as solutes are excluded from extracellular ice. We investigated the possibility that this hyperosmotic shock elicits an acute regulatory volume increase (RVI) by monitoring the response of epithelial cell volume in the Malpighian tubules of ...
Iyamu E W - - 1998
Trimidox (3,4,5-trihdroxybenzamidoxime) has been shown to reduce the activity of ribonucleotide reductase with accompanied growth inhibition and differentiation of mammalian cells. Hydroxyurea (HU) is the only ribonucleotide reductase inhibitor in clinical use for the treatment and management of sickle cell anemia, since this compound increases fetal hemoglobin (Hb F) production: ...
Sage J R - - 1998
To determine the susceptibility of Escherichia coli O157:H7 to freezing and thawing in apple cider, methods that recover injured cells are needed for accurate enumeration. This study compared the ISO-GRID hydrophobic grid membrane filter (HGMF) SD-39 agar method to two other methods: a reference most probable number (MPN) method, and ...
Devireddy R V - - 1998
A new technique using a differential scanning calorimeter (DSC) was developed to obtain dynamic and quantitative water transport data in cell suspensions during freezing. The model system investigated was a nonattached spherical lymphocyte (Epstein-Barr virus transformed, EBVT) human cell line. Data from the technique show that the initial heat release ...
Aslam I - - 1998
Testicular cell suspensions were prepared from obstructive and non-obstructive azoospermic men and were cultured in vitro for 96 h as (i) mixed cell populations and (ii) isolated homogeneous populations of primary spermatocytes, round spermatids and elongating spermatids. The cells lost their viability gradually during the first 24 h period. By ...
Lekic P C - - 1998
Viable periodontal ligament (PL) cells are required for PL healing of avulsed teeth following replantation. If immediate replantation cannot be accomplished, the ability of PL progenitor cells to reproduce (clonogenic capacity) and recolonize the wound may be extended by prevention of desiccation and storage in physiological media. This investigation examined ...
Tatsutani K - - 1998
The thermodynamics of intracellular ice nucleation are important in low-temperature biology for understanding and controlling the process of cell destruction by freezing. We have developed a new apparatus and technique for studying the physics of intracellular ice nucleation. Employing the principle of directional solidification in conjunction with light microscopy, we ...
Coombes A L - - 1998
Storage and resuscitation of MDCC-MSB1 cells, most commonly used for the propagation of chicken anemia virus was studied. Cells were frozen slowly in RPMI medium 1640 with 10% or 20% fetal bovine serum and 20% dimethyl sulfoxide, held at -70 C overnight, and placed into liquid nitrogen the next day. ...
McHenry C R - - 1997
BACKGROUND: Higher failure rates have been reported with cryopreserved versus fresh parathyroid autografts. The purpose of this study was to investigate the effects of cryopreservation on live cell yield and to determine if freezing tissue as dispersed cells could improve functional outcome. METHODS: Live cell yield and cytosolic calcium (Ca[i]) ...
Slivinsky G G - - 1997
Cellular electrophoretic mobility values of 288 types of eucaryotic cells were collected from literature published worldwide by a series of authors during the past forty years and arranged in a list. This list contains well-known recent electrophoretic results and also data that cannot be found anymore with modern literature retrieval ...
Wang A W - - 1997
OBJECTIVES: To test the hypothesis that conventionally used procedures for semen cryopreservation may cause an increase in the production of reactive oxygen species (ROS) by sperm or by seminal leukocytes, which may contribute to poor sperm function following cryopreservation. METHODS: Eighteen semen specimens with normal parameters from healthy male donors ...
Takano T - - 1997
To measure thyroid-stimulating antibody (TSAb) in sera from patients with Graves' disease, we developed a new assay system with using frozen stocks of CHO-K1 cells. CHO-K1 cells transfected with cloned thyrotropin (TSH) receptor on a 96 well plate were frozen in Cell Banker and stored at -70 degrees C. Three ...
Chen J Y - - 1997
The binding of merocyanine 540 (MC540) to murine myeloid leukemia (M1) cells and normal erythrocytes was measured by fluorescence digital imaging microscopy using an intensified charge-coupled device. It was found that, on average, about three times more MC540 were bound to a unit membrane area of M1 cells than erythrocytes, ...
Kino K - - 1997
To execute a strategy for reconstituting genetic resources from cryopreserved blastodermal cells, experiments were conducted to optimize conditions for producing chimeric chickens from frozen-thawed blastodermal cells. Stage X blastodermal cells were collected from Barred Plymouth Rock embryos and dispersed. Cells were resuspended in 10% dimethyl sulfoxide in Dulbecco's modified Eagle's ...
Koushafar H - - 1997
OBJECTIVES: Recent studies show that prostate adenocarcinoma cells can survive cryosurgery and that cell destruction depends on the specific thermal parameters used during freezing. The goal of this preliminary study is to determine whether certain chemical compounds, known as antifreeze proteins, can induce complete human primary prostatic adenocarcinoma cell destruction ...
Darr T B - - 1997
The cellular response of isolated hepatocytes from pigs, humans, and human hepatoblastoma cells to freezing was characterized using cryomicroscopy and analyzed using a thermodynamic model for water transport and Intracellular Ice Formation (IIF). The value for the reference permeability, Lpg, was found to be 5.8(10)-13, 1.62(10)-13, and 2.7(10)-14 m/Ns for ...
Barkema H W - - 1997
The objective of this study was to determine the effect of freezing and the duration of freezing on somatic cell count (SCC) in milk samples from quarters with no signs of clinical mastitis. Effect was determined by a fluoro-opto-electronic cell counter. Samples were frozen in a commercial freezer at approximately ...
Mohan J S - - 1997
1. Chronic leg ulceration is a major cause of morbidity in patients with homozygous sickle cell disease; the ulcers commonly resolve on bed rest. We have therefore compared the cutaneous vascular response to dependency in three groups of eight patients with sickle cell disease (those with an active ulcer, with ...
Berger W K - - 1996
The formation of intracellular ice (IIF), usually a lethal event to be avoided when cryopreserving cells, should, however, be enforced during the cryosurgical destruction of tumour cells. IIF has been investigated so far only in single cells in suspension. Because cells in tissues cannot be successfully cryopreserved, in contrast to ...
Tatsutani K - - 1996
OBJECTIVES: Recent advances in imaging technology and cryotechnology have rekindled interest in prostate cryosurgery. Cryosurgery, however, cannot be applied precisely without knowing how the thermal variables used during the procedure affect tissue destruction. The goal of this article is to provide quantitative values for the relationship between thermal variables during ...
Salmon F - - 1996
1. The possibility of using hepatocytes from food-producing animals in order to determine the metabolic routes of pesticides has been studied using a strobilurin fungicide (BAS 490 F). Hepatocytes suspensions were prepared from goat, pig, hen, and rat and the major metabolites were compared with those obtained in vivo. 2. ...
Hassan H T - - 1996
Allogeneic transplantation of selected CD34+ cells, rather than conventional transplantation of bone marrow (BM) harvest or peripheral blood (PB) leukapheresis products, has the advantage of reducing volume, facilitating storage and decreasing the amount of dimethylsulfoxide (DMSO) and cell lysis products, as well as reducing the number of T-lymphocytes responsible for ...
Zieger M A - - 1996
Successful cryopreservation of tissues will ultimately require a more detailed understanding of how the in situ environment modifies cell responses during cooling and warming. Low-temperature responses of porcine split-thickness skin and isolated basal keratinocytes were compared after various cooling protocols and in the presence and absence of cryoprotectants. Recovery was ...
Rajashekar C. B. - - 1996
Freeze-induced cell tensions were determined by cell water relations in leaves of broadleaf evergreen species and cell cultures of grapes (Vitis spp.) and apple (Malus domestica). Cell tensions increased in response to cold acclimation in leaves of broadleaf evergreen species during extracellular freezing, indicating a higher resistance to cell volume ...
Rajashekar C. B. - - 1996
The freezing characteristics and development of cell tension during extracellular freezing were examined in supercooling stem tissues of riverbank grapes (Vitis riparia) and cold-hardened leaves of live oak (Quercus virginiana) and mountain cranberry (Vaccinium vitis-idaea). Dormant stem xylem and pith tissues of river-bank grapes were resistant to freeze-induced dehydration above ...
Walter H - - 1996
Counter-current distribution (CCD) of red blood cells (RBC) from individuals with homozygous sickle cell (HbSS) disease in a charge-sensitive aqueous dextran-poly(ethylene glycol) phase system, which fractionates cells on the basis of surface properties, indicates that the percentage of irreversibly sickled cells (ISC) increases and the percentage of reticulocytes decreases with ...
Lai Y M - - 1996
PURPOSE: In order to develop a better system for support of human sperm function in vitro, we conducted studies to evaluate whether reproductive tract cells are better than non-reproductive tract cells as an adjunt in that regard. METHODS: Human spermatozoa were cocultured with Vero cells, with human oviduct cells and ...
de Leo G - - 1996
Previous studies on the ascidian Ciona intestinalis have shown that an encapsulation response is experimentally induced by inserting vertebrate erythrocytes into the tunic, which initiates a massive inflammatory cell infiltration to isolate the injured area. Several hemocytes contribute to capsule formation, destruction of the foreign cells, tunic regeneration, and wound ...
Cao Y - - 1996
Viable sperm cells of Nicotiana tabacum were isolated by the semi-vivo technique. After pollination, excised styles were floated, cut end immersed, in a solution of 15% sucrose with 0.01% boric acid and 0.03% Ca(NO3)2 at 27 degrees C in a growth chamber until pollen tubes emerged. After sperm cells were ...
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