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At least 19 recordsLinked to original sources
PubMed1990

Suitability of cryopreserved samples for pharmacological studies of ciliary activity.

The effect of terbutaline sulfate on the ciliary activity of fresh and cryopreserved human nasal epithelium was evaluated. Cryopreservation had no effect on baseline ciliary beat frequency. Both fresh and cryopreserved samples exposed to 10(-4) M terbutaline showed a statistically significant increase in ciliary beat frequency (27 and 25%, respectively). When the percentage changes after drug challenge for fresh and cryopreserved samples were compared no statistical difference emerged. It is concluded that cryopreservation in liquid nitrogen at -196 degrees C does not affect membrane receptors, at least beta-adrenergic receptors, and therefore cryopreserved samples are suitable for pharmacological studies of ciliary activity.

Adult↗
PubMed1990

Chromosome analysis of cryopreserved cells.

We describe a technique for freezing and thawing human leukemic cells for cytogenetic studies. We studied 64 harvests on 26 cryopreserved samples from 20 individuals. Chromosome quality was best in the samples from patients with myeloid disturbances. Successful chromosome studies of approximately 50% of the samples were accomplished. Cryopreservation of leukemic cells is not a substitute for fresh material because the method produces relatively few metaphases and mediocre chromosome spreading and banding. However, when rigid and appropriate research objectives are applied, chromosome analysis of cryopreserved leukemic cells can be a viable alternative to analysis of fresh cells.

Adolescent↗
PubMed1986

Effect of sample holding, cryopreservation, and storage on the human lymphocyte cytogenetic test.

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 degrees C, freezing lymphocytes in dimethylsulfoxide at -180 degrees C, and keeping fixed cells for 6 days at 4 degrees C before slide-making were examined. Final cell count, mitotic index, percentage of cells in first division, percentage of cells with chromosomal aberrations, and sister chromatid exchange per cell were measured in paired cultures. A significant increase in the frequency of cells with chromatid breaks occurred after prolonged fixation, so all other results were obtained from freshly fixed cells. Although holding at 22 degrees C and cryopreservation had significant effects on the mitotic index and entry of lymphocytes into the cell division cycle, the cytogenetic endpoints were not affected by any of the sample manipulations. Thus, samples can be held at 4 degrees C or 22 degrees C for 24 hours, or frozen lymphocytes can be stored for at least a week, without altering the cytogenetic endpoints.

Cells, Cultured↗
PubMed1989

Fertilization in vitro of human oocytes by spermatozoa collected in different stressful situations.

It has been shown that semen quality is impaired in couples undergoing in-vitro fertilization (IVF), probably due to stress. A possible effect of stress on the ability of spermatozoa to fertilize human oocytes in vitro was analysed in the present study composed of 26 couples with normozoospermic men undergoing IVF. A semen sample was obtained during the infertility work-up and was cryopreserved (sample 1). A second sample (sample 2) was provided after oocyte retrieval during the IVF cycle. Sample 1 was thawed and both samples were washed and preincubated for oocyte insemination. One-hundred-and-five oocytes were inseminated using thawed sample 1, and 120 with sample 2. Semen parameters such as density, progressive motility and percentage of abnormal forms were compared between sample 1, before and after freezing, and sample 2. Only motility was significantly (P less than 0.01) decreased by cryopreservation in sample 1, but no parameter was significantly different when fresh sample 1 was compared to sample 2. The fertilization rate was 78.6% using sample 1 in comparison to 87.5% when sample 2 was employed (not significant, NS). Cleavage rates were 77.7 and 89.7%, respectively (NS). A group of five patients undergoing IVF who needed donor semen served as a control for the effect of sperm cryopreservation on IVF. In these cases, the donor was asked to provide a fresh sample. Half of this sample was frozen and thawed. Subsequently, fresh and thawed samples were prepared for insemination and oocytes inseminated either with the fresh preparation (n = 24) or the frozen and thawed spermatozoa (n = 22).(ABSTRACT TRUNCATED AT 250 WORDS)

Cryopreservation↗
PubMed1988

[The Munich cryopreserved sperm bank--intermediate 1974-1986 evaluation].

The storage of spermatozoa from tumour patients in sperm banks is an important medical task. As a result of improved treatment strategies the survival rate, particularly in patients with testicular tumours and Hodgkin's disease, is excellent if the diagnosis is made early. However, the necessary therapeutic measures often lead to the mutilation of reproductive function. At the Department of Dermatology at the University of Munich a sperm bank has been in existence since 1974; most of the patients who consult the sperm bank are men with testicular tumours. A synopsis of the last 12 years provides information about the patients, indications for storage, the method of preservation used and the fate of the cryopreserved samples used for insemination. To guarantee that optimal results are achieved, cryopreserved sperm samples should only be used by gynaecologists who are particularly experienced in the treatment of sterility.

Adolescent↗
PubMed1976

Electrophoretic distributions of human peripheral blood mononuclear white cells from normal subjects and from patients with acute lymphocytic leukemia.

The electrophoretic mobilities of mononuclear white cells from the peripheral blood of normal subjects and leukemic patients were measured. Analysis of both fresh and cryopreserved samples of each type showed that cryopreservation had no distinguishable effect on the electrophoretic distribution of either normal or leukemic cells. Mode mobilities (mobilities at which maximum intensities are observed) of cells from nine leukemic patients were 7-28% below the average mode mobility of normal cells. The standard deviation of the electrophoretic mobilities of normal cells was 2%. Normal cells had an asymmetric, often bimodal, electrophoretic distribution; leukemic cells consistently had a single symmetric distribution.

Electrophoresis↗
PubMed1990

Cryopreservation of equine mononuclear cells for immunological studies.

A rapid and simple technique for the cryopreservation and recovery of equine mononuclear cells was developed. Buffy-coat leukocytes were frozen in autologous plasma containing 10% DMSO and mononuclear cells were recovered by gradient sedimentation using a standard Ficoll-Hypaque purification procedure. The total numbers of mononuclear cells recovered from cryopreserved samples were 94%-82% of those recovered from fresh blood samples. The functional capabilities of the mononuclear cells from cryopreserved buffy coat preparations were compared with those of mononuclear cells from fresh samples by measuring the ability of cells to proliferate in response to mitogens and specific antigens. Cell-surface antigen expression was measured using monoclonal antibodies in conjunction with flow cytometric techniques and alloantisera in a complement mediated cytotoxicity assay. Cryopreserved mononuclear cells were capable of proliferating normally when stimulated with several mitogens, pokeweed mitogen, phytohemagglutinin and concanavalin A, and a single specific antigen preparation, equine influenza-2 (Equi-2) proteins. The maximum levels of proliferation induced by varying the concentrations of mitogens or the Equi-2 proteins were the same for both the fresh and cryopreserved cells. However, the cryopreserved cells usually required one more day in culture to attain maximum proliferation levels. Flow cytometric analysis of the samples demonstrated that the relative proportions of different lymphocyte populations were not altered by the cryopreservation step. Similarly, MHS alloantigen expression was not altered. The simplicity of the technique coupled with the retained functional properties allows for the cryopreservation of large numbers of leukocytes and the ability to assay various immune functions at a later time.

Animals↗
PubMed1990

The effects of cryopreservation on membrane integrity, membrane transport, and protein synthesis in rat hepatocytes.

The cryopreservation of hepatocytes is of particular interest as a step in the possible treatment of some inborn disorders of metabolism. This study examines the metabolic damage that occurs as a result of the freeze-thaw procedures and during subsequent incubation periods of isolated rat hepatocytes. Even for freshly prepared hepatocytes, the presence of 1.8 M of Me2SO during incubation led to a rapid decline in viability. Optimal recovery after cryopreservation was obtained when incubation was started after the progressive removal of Me2SO. A buffer medium characterized by an intracellular electrolyte composition (Euro-Collins) proved particularly beneficial to the membrane integrity, probably by protecting the (Na+,K+)ATPase pump activity. The interpretation of viability using the trypan blue exclusion test was generally confirmed by the metabolic analysis of protein synthesizing activity and membrane transport function which are regarded as more rigorous tests of functional viability. The incorporation of L-[U-14C]isoleucine into the proteins of fresh hepatocytes during the first hour of incubation progressively leveled off over the next 2 hr. The cryopreserved hepatocytes showed a similar pattern although at a lower level of activity. Even after 3 hr of preincubation, the subsequent addition of labeled isoleucine still indicated a residual protein synthesizing activity. The active transport of alpha-amino[1-14C]isobutyric acid through the cell membranes reached a peak value after 60 min of incubation of fresh hepatocytes, and after 40 min of incubation of cryopreserved cells, followed by a steep decline as expression of rapid membrane deterioration. Again, the membrane transport pattern for the cryopreserved samples occurred at a lower level of activity. After preincubation of fresh and cryopreserved hepatocytes for 180 min, subsequent addition of labeled alpha-aminoisobutyric acid did not show any further significant metabolic activity. Initially the amino acid availability appeared to control protein synthesizing activity while, as membrane transport became seriously damaged, incorporation leveled off with only a low metabolic activity remaining. Although cryopreserved hepatocytes were susceptible to faster deterioration during subsequent incubation, considerable metabolic activity was retained. However, fresh and cryopreserved hepatocytes expressed metabolic functions at significantly different activities. Moreover, the differences between fresh and cryopreserved cells varied with the particular cellular function being examined.

Amino Acids↗
PubMed1989

Human fetal liver as a valuable source of haemopoietic stem cells for allogeneic bone marrow transplantation.

The CFU-GM and T cell contents of human fetal livers were studied at various times between 6-14 weeks of gestation. The number of CFU-GM increased parallel to gestational age, especially after week 10. Cells bearing mature T cell markers, however, were found only in one case out of 35 fetal liver samples. Cryopreservation of fetal liver cells hardly affected the viability and proliferative capacity of CFU-GM in the sample. According to these findings fetal liver is, at least up to the 14th gestational week, practically free of mature T cells but it does contain a considerable amount of CFU-GM (an accepted indicator of pluripotent stem cell content), consequently fetal liver can be considered as a valuable source of haemopoietic stem cells for allogeneic bone marrow transplantation for children.

Antigens, Differentiation, T-Lymphocyte↗
PubMed1975

Hemopoietic colony forming units in fresh and cryopreserved peripheral blood cells of canines and man.

Colony forming units (CFUa) were assayed in the peripheral blood and separated mononuclear cells of canines and man. Fresh and cryopreserved samples were studied. By plating 3 x 10-5 canine buffy coat cells or 3 x 10-6 human buffy coat cells between 33 plus or minus 6.6 and 38 plus or minus 1.0 colonies were observed. A high degree of reproducibility was shown for duplicate plates and on repeated testing. Cryopreservation for a one-month period resulted in a minimal recovery of 80 per cent CFUa for canine cells and 96 per cent for human cells. In vivo correlation between peripheral blood CFUa and marrow repopulation was assessed indogs following supralethal whole body irradiation. Prompt repopulation of the marrow was observed and this correlated well with the CFUa assay following infusion of stored buffy coat cells. It was concluded that the peripheral blood of both man and dog have significant numbers of cells with CFUa capabilities that may be potentially useful for marrow grafting purposes.

Animals↗
PubMed1989

The effect of cryopreservation on the biomechanical behavior of bovine articular cartilage.

The short-term effect of cryopreservation on specific mechanical behaviors of bovine articular cartilage has been investigated. A flat-ended nonporous indentor was used in a nondestructive, repetitive, axisymmetric unconstrained testing system. Cyclical indentation from a fixed position to a fixed load was applied until a steady-state load-deformation relationship (limit cycle) was achieved. Indentation behaviors measured from the limit cycles of each articular cartilage specimen before and after treatment were compared. Testing was done in vitro using fresh, mature bovine radiocarpal joints. Twenty pairs of cartilage-subchondral bone cores from anatomically similar sites on contralateral joints were separated into three groups; thickness controls, dimethylsulfoxide (DMSO) controls, and cryopreserved experimental samples. Thickness controls and DMSO controls were used to examine the isolated effects of the thickness measurement and DMSO incubation techniques on articular cartilage indentation characteristics. Experimental samples were cryopreserved using DMSO, their thicknesses similarly measured and indentation behaviors examined. Following testing, histological and histochemical assessment of the specimens confirmed the nondestructive nature of the tests. Intra- and intergroup comparisons of controls and experimentals revealed no statistical differences in the mechanical behaviors measured from the limit cycle or in cartilage thickness. These results indicate that the cryopreservation protocol used did not have an effect that we could measure on these specific mechanical behaviors of articular cartilage.

Animals↗
PubMed1991

A monoclonal antibody to common acute lymphoblastic leukemia antigen (neutral endopeptidase) immunostains senile plaques in the brains of patients with Alzheimer's disease.

We immunostained brain tissues of patients with Alzheimer's disease (AD) together with non-demented aged and younger controls with a battery of anti-human hemopoietic cell monoclonal antibodies (OK series, Ortho Diagnostics Co., Ltd. and some others) by the avidin-biotin-peroxidase complex (ABC) method to see if any epitopes are shared with the nervous system or might contribute to the neurodegenerative changes in this disease. One out of 29 monoclonal antibodies, OKBcALLa, which recognizes common acute lymphocytic leukemia antigen (CALLA, CD10), immunostained senile plaques in the brains of patients with AD. The pattern and intensity of this staining, using cryopreserved samples, was almost identical to that obtained with anti beta-protein. Thus, senile plaques in the Alzheimer's brain share an epitope with CALLA.

Aged↗
PubMed1992

Feasibility of the fluorometric microculture cytotoxicity assay (FMCA) for cytotoxic drug sensitivity testing of tumor cells from patients with acute lymphoblastic leukemia.

The automated fluorometric microculture cytotoxicity assay (FMCA) was used for chemotherapeutic drug sensitivity testing of fresh and cryopreserved tumor cells from patients with acute lymphoblastic leukemia (ALL) at diagnosis and relapse. The technique success rate was 87% for fresh and 81% for cryopreserved samples. Up to 16 different cytotoxic drugs were routinely tested, but neither asparaginase nor methotrexate produced dose-response related cell kill. FMCA data showed good correlation to the well established Disc assay and the drug sensitivity reported by the FMCA was in good agreement with known clinical activity. Samples from children and initial ALL tended to be more drug sensitive than those from adults and ALL at relapse, respectively. For 36 samples clinical outcome was correlated to the quartile position in comparison to all other samples for the most in vitro active drug actually given to the patient. For patients with samples in the first, second, third, and fourth quartiles, the probabilities of complete remission were 89, 57, 38, and 0%, respectively. Using the median value as cut-off line, the sensitivity and specificity of the assay were 87 and 62%, respectively. It is concluded that the FMCA with a minimum of effort and with high success rate report clinically relevant drug sensitivity profiles for ALL.

Antineoplastic Agents↗
PubMed1986

Immunodeficiency in rhesus monkeys associated with the original Mason-Pfizer monkey virus.

The Mason-Pfizer monkey virus (MPMV) was reisolated from a cryopreserved sample of the original MPMV-containing rhesus breast carcinoma, and complete integrated MPMV provirus was detected in chromosomal DNA of this tumor. Reanalysis of the in vivo pathogenicity and molecular character of MPMV reisolated from the rhesus breast tumor and analysis of the original MPMV after long-term in vitro propagation in human and rhesus cells show that the original MPMV produces an acquired immunodeficiency similar to that caused by the recently described simian acquired immune deficiency syndrome type D retroviruses, and the MPMV genome and its immunosuppressive effect in vivo have remained stable despite prolonged in vitro passage in human and rhesus cells.

Acquired Immunodeficiency Syndrome↗
PubMed1989

Comparison of human long-term bone marrow cultures (HLTBMCs) established from fresh and post-cryopreservation bone marrow samples from living and cadaver donors.

Human long-term bone marrow cultures (HLTBMCs) were established from thawed post-cryopreservation, as well as from cadaver donor bone marrow (BM) samples. The longevity was similar in the different series of HLTBMCs examined. CFU-GM could be cultured out of cadaver donor BM. This indicates that previously healthy people, under the conditions generally accepted as suitable for organ donation, could become suitable donors for allogeneic BM transplantation.

Bone Marrow Cells↗
PubMed1989

Longitudinal study of the in vivo hprt mutant frequency in human T-lymphocytes as determined by a cell cloning assay.

The in vivo frequency of mutants resulting from mutation at the hprt locus in human T-lymphocytes can be determined by a cloning assay. This assay quantifies the frequency of 6-thioguanine-resistant (TGr) T-cells through growth of colonies in 96-well microtiter dishes. The reproducibility of the TGr mutant frequency values has now been assessed in a longitudinal study of six individuals (three male, three female, aged 22-33 years) employing 4-5 blood samples over a 26-37 week time period. Cloning assays were performed with both fresh and cryopreserved cell samples. No significant differences were found among the mutant frequency values for multiple samples from each individual with both fresh and cryopreserved cell samples. These results demonstrate the reproducibility of this cloning assay for in vivo mutant frequency determinations in human T-lymphocytes.

Adult↗
PubMed1985

Frequency and coordination of ciliary beat after cryopreservation of respiratory epithelium.

The effect of cryopreservation on human nasal mucosal biopsies was evaluated by determining the frequency and coordination of the ciliary beat. Samples were cryopreserved in a medium containing 80% Gey's balanced salt solution, 10% dimethyl sulfoxide, and 10% fetal calf serum. After thawing, the samples were put in a solution of 90% Gey's balanced salt solution and 10% fetal calf serum. Video recordings of the samples before and after cryopreservation were compared using a semiquantitative method. All the frequencies and coordination patterns seen before cryopreservation could be found in the sample after cryopreservation. It is concluded that ciliated epithelial biopsies can be stored in liquid nitrogen with the maintenance of ciliary beat frequency. In the recorded ciliated cells the ciliary beat coordination was slightly reduced; a lack of coordination was present in 20% of cells after cryopreservation as compared to 10% before cryopreservation.

Adult↗
PubMed1991

Cryopreservation of the occasionally improved semen samples for intrauterine insemination: a new approach in the treatment of idiopathic male infertility.

OBJECTIVE: To assess the value of treating idiopathic male infertility by intrauterine insemination (IUI) of the occasionally improved cryopreserved semen. DESIGN: Two groups of idiopathic oligospermic patients were chosen at random and treated by IUI using processed fresh semen in group A and the best available cryopreserved semen samples pooled with fresh samples in group B. SETTING: Egyptian IVF-ET Centre, Maadi, CAiro, Egypt. PATIENTS, PARTICIPANTS: One hundred fifty infertile couples because of idiopathic oligoasthenospermia. INTERVENTION: Intrauterine insemination. MAIN OUTCOME MEASURE: The pregnancy rate was evaluated after an average of three treatment cycles. RESULTS: The pregnancy rate (PR) was significantly higher in group B when compared with group A. The improvement in the PR was highly significant in the subgroup of patients for whom reasonable semen samples could be collected and cryopreserved. CONCLUSIONS: Our study indicates that IUI with fresh semen pooled with cryopreserved occasionally improved semen samples for the treatment of oligoasthenospermia results in an improved PR.

Cryopreservation↗