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PubMed1999

[Separation of hematopoietic progenitor cells from peripheral blood in patients with hemato-oncologic malignancy].

BACKGROUND: Transplantations of haematopoietic progenitor cells from peripheral blood (PBPC) are able to ensure haematopoietic and immunological reconstitution as well as stable long term engraftment. Autologous PBPC are administered after previous myeloablative chemotherapy to patients with haematological and non-haematological malignancies. The objective of the submitted study was to follow-up the results of autologous separations of PBPC in patients with a good effect of mobilisation therapy. The authors evaluated in PBPC concentrates the content of cell parameters needed for transplantation. In the subsequent part of the trial they mention the times of engraftment after autologous transplantation. METHODS AND RESULTS: The authors evaluated parameters of 26 separations of PBPC in 11 haematooncological patients with a good effect of mobilisation therapy and with concentration of CD 34+ cells higher than 20 x 10(3)/ml of peripheral blood. The separations of PBPC were implemented on the Cobe Spectra and Baxter CS 3000 Plus equipment under a standard regime with processing of 12 l blood, i.e. 2.7 total blood volumes of the patients. In the mentioned group of patients already from one separation an adequate amount of CD 34+ cells for their transplantation was obtained. Transplantation doses were prepared on average from two separations and amounted as regards MNC/kg, CD 34+ cells/kg and CFU-GM/kg to 4.3 x 10(8), 17.1 x 10(6) and 2.5 x 10(4). The assembled parameters correspond to, or in some parameters exceed, recommended amounts for their transplantation. CONCLUSIONS: In well mobilised patients under the regime of standard separations adequate amounts of progenitor cells for their autologous transplantation were obtained. Transplantation doses were prepared from two collections. Investigation of pre-separation concentration of CD 34+ cells in the peripheral blood is a reliable indicator for starting PBPC separation. Early post-transplantation results indicate the time of engraftment 10 days on average and minor need of substitution therapy with blood products.

Adult↗
PubMed2000

Pituitary and ovarian response to transient doe-litter separation in nursing rabbits.

The effects of a transient doe-litter separation on plasma prolactin, FSH and oestradiol concentrations, as well as the effect on LH response to exogenous GnRH administered at the time of artificial insemination, were determined in nursing rabbits. The effects on fertility, and litter size after parturition, as well as litter survival after doe-litter separation, were also studied. Control does (n = 12) had free access to nursing, whereas biostimulated does (n = 12) were separated from their litters for 48 h before artificial insemination. Plasma prolactin concentrations were decreased 24 h after the doe-litter separation (P < 0.05). The response of prolactin to suckling reached 10 times the basal values measured on day 10 after parturition (P < 0.0001). Increased oestradiol concentrations were found during the 48 h after the doe-litter separation: at 0 h, before artificial insemination (P< 0. 0001), 1.0-2.0 h after artificial insemination (P < 0.001), at 2.5 h (P < 0.05), 3.0 h (P < 0.01), and at 3.5 h (P < 0.05) after artificial insemination. Exogenous GnRH administered at the time of artificial insemination caused a greater LH response in does previously separated from their litters during 48 h (P < 0.01). The transient doe-litter separation did not affect plasma FSH concentrations, fertility, litter size or litter survival. These results suggest that a transient separation of nursing does from their litters before artificial insemination results in a decrease in plasma prolactin concentrations that could promote growth of follicular waves, and high steroidogenesis activity, leading to increased oestradiol concentrations and inducing higher sensitivity of the pituitary gland to exogenous GnRH. These findings associated to the absence of suckling episodes would lead to higher LH response and, therefore, exert a major effect on fertility.

Animals↗
PubMedDate not supplied

Thin-layer chromatography--a useful technique for the separation of enantiomers.

Separation of enantiomers has become a well-established technique in many fields of science over the last decade. Unfortunately, even though there are a large number of chiral stationary phases able to perform enantiomeric separation, there is still a great deal of trial and error in developing a method for the separation of enantiomers. Thin-layer chromatography is a very versatile technique, which has brought much advancement in various fields of science. The simplicity of the technique makes it amenable for separation of enantiomers. This paper will present a review of the literature concerning separation of enantiomers. Because of the process of trial and error present in developing a chiral separation method, this paper also presents the mechanism underlying each form of separation. Thus, the methods are presented according to the main mechanism governing the particular separation.

Chromatography, Thin Layer↗
PubMed2002

Urine separating sewage systems--environmental effects and resource usage.

Effects of urine separation on the environment and resource usage were estimated using the simulation package ORWARE. Measurements on the urine-separating system in the housing district Palsternackan in Stockholm and on the fertilising effect of the urine were used in the simulations. The tenants were at home 65% of the time and separated 65% of the urine. Under these conditions, urine separation decreased the waterborne emissions of nitrogen and phosphorus by 55% and 33% respectively. Compared to the conventional system, urine separation increased the flow from the wastewater system to agriculture of plant-available nitrogen by a factor of 28, phosphorus by a factor of 1.35 and potassium by a factor of 23. Urine is a well-balanced complete fertiliser with very low concentrations of heavy metals. Urine separation conserved energy as long as the urine was transported distances shorter than 221 km to the field with a truck and trailer. If all the urine had been separated and transported only 1 km, the energy saving would have been 36%. In this and in previous studies, urine separation proved to be an improvement over the conventional system as regards environmental effects and resource usage.

Conservation of Natural Resources↗
PubMed2003

[Historical study of separation technology innovation in the field of pharmaceutical science].

The separation of organic compounds has been carried out using the method of distillation and recrystallization since the 17th century.1st separation technology innovation (1950s to 1960s). After World War II, the science of separating organic compounds evolved to the use of paper or column chromatography. 2nd separation technology innovation (1960s to 1980s). In the 1960s, thin-layer chromatograpy (TLC) was developed. TLC is a convenient analytical technique for organic compounds. Separation methods for organic compounds using column chromatography and preparative TLC were carried out as practical applications. Gas chromatography (GC) was also introduced in the 1960s. GC is a useful analytical method for a mixture of various volatile organic compounds. Many GC instruments with new kinds of sensors were developed. Gas chromatography of nonbenzenoid organometallic compounds and metal complexes was successfully conducted by the author. 3rd separation technology innovation (1980s to 1990s). In the 1980s, high-performance liquid-chromatography (HPLC) was developed. HPLC analytical methods were useful for various kinds of organic compounds. In the 1990s, LC-MS and LC-NMR instruments were introduced for biomedical products. 4th separation technology innovation (1990s to present). Several new ionization methods for mass-spectrometry (electrospray, matrix-aided lazer desorption ionization, etc) are applied for proteins and biomedical products. Several new separation technologies (supercritical field chromatography, capillary electrophoresis, field-flow fractionization, etc.) are now being developed.

History, 20th Century↗
PubMed1997

[Separation of drugs cephalexin, ampicillin, and their biosynthetic precursors L-Phe-L-Cys-D-Val and D-Phe-L-Cys-D-Val by capillary zone electrophoresis].

The separation of drugs cephalexin, ampicillin and their biosynthetic precursors L-Phe-L-Cys-D-Val and D-Phe-L-Cys-D-Val was investigated by using capillary zone electrophoresis in acidic Tris-H3PO4 buffer at pH 2.3. With 50 mmol/L Tris-H3PO4 (pH 2.3) buffer, L-Phe-L-Cys-D-Val and D-Phe-L-Cys-D-Val were only partially separated whereas near baseline separation was achieved between cephalexin and ampicillin. The experiments showed that the addition of beta-type cyclodextrins (beta-CD) to the running buffer can influence the separation selectivity. When beta-CD was used as buffer additives at 12 mmol/L, the separation between L-Phe-L-Cys-D-Val and D-Phe-L-Cys-D-Val was much improved, however, the separation between cephalexin and ampicillin was impaired. When using 50 mmol/L Tris-H3PO4 containing 12 mmol/L DM-beta-CD (pH 2.3) buffer system, all compounds investigated were completely separated. This separation method is simple, fast and easy to operate. It involves only the conventional reagents with a much lower run cost than using HPLC. It is expected to be used in the synthetic process monitoring.

Ampicillin↗
PubMed2005

[Anatermic separated epiphysis or avulsion fracture: image observation].

OBJECTIVE: To explore an approach to distinguish avulsion fracture of articular portion from anatomic separated epiphysis. METHODS: 21 cases with suspicioned avulsion fracture of articular portion of tubular bone were reviewed. The cortical continuity of separate small bone and contiguous bone portion was investigated. The swell of soft tissue around these small bones was observed simultaneously. Then the configuration of the fracture was researched by injury mechanics. RESULTS: Continued bone cortex between separate small bone and corresponding bone was seen in 15 cases, so they were considered as a separate epiphysis. Sharp linear fracture between the separate small bone and corresponding bone were seen in 6 cases. The swell of soft tissue around the separate small bone was observed in all cases, so they were considered as a avulsion fracture. CONCLUSION: The meticulous investigation of separated small bone at the articular portion by image observation is of important value for distinguishing avulsion fracture from anatomic separate epiphysis.

Adolescent↗
PubMed1978

Heart rate and body temperature in separated monkey infants.

Heart rate (HR) and body temperature (BT) were recorded from ten unrestrained group-living M. nemestrina (pigtail) monkey infants, using totally implantable multichannel biotelemetry systems, during a 4-day base line (preseparation) period, during the agitation-depression reaction accompanying 4 days of maternal separation, and for several days following reunion with the mother. Quantified behavioral data were collected in nine of the ten infants. Mean daytime (1000 to 1600 hr) and nightime (2200 to 0400 hr) HR and BT values were computed for each infant, and for the group as a whole. The behavioral agitation reaction immediately following separation was accompanied by increases in both HR and BT. Beginning with the first night of separation, both HR and BT showed marked decreases from base line. Whereas group mean HR and BT changes were maximal early in the separation, behavioral indices of depression tended to be maximal later in the separation period. Reunion with the mother tended to normalize HR and BT in most infants. Two infants exhibited sudden transient reversible drops in nocturnal BT well into the separation period, suggesting an impairment in thermoregulatory mechanisms during the period of depressive behavior. One infant had a prolonged separation-induced decrease in HR that persisted throughout reunion, indicating that the stress of maternal separation may induce physiological changes that considerably exceed the duration of the effective stress.

Animals↗
PubMed1985

Zonal unit-gravity elutriation. A new technique for separating large cells and multicellular complexes from cell suspensions.

A new and simple technique, zonal unit-gravity elutriation, has been devised for separating very large cells, multicellular complexes, or small organisms from suspensions consisting mainly of small cells. The separation vessel is a conical chamber with an entrance at the lower, narrower part of the cone and an exit at the upper, wider part of the cone via a dome-shaped lid. A baffle at the entrance prevents turbulence from incoming fluid. Chambers of differing widths and wall slopes are chosen depending on the sedimentation rate of the particles to be separated. A small volume of the cell suspension is placed in the chamber on the bench in a cold-room. Medium stabilized by a shallow density gradient is pumped into the base of the chamber and ascends, creating a decreasing velocity gradient. Cells sediment at unit-gravity against this ascending counterstream, and are separated into bands according to sedimentation velocity. By adjusting the flow rate of the medium, different sizes of cells can be separated. Tumor cells can be enriched, and larger blast cells can be separated from small cells in lymphoid cell suspensions. The procedure produces complete separation of thymic nurse cells (epithelial-lymphoid complexes) from free thymocytes in digested thymus suspensions and produces substantial enrichment of thymic rosettes (macrophage-lymphoid complexes). A very favorable situation for applying this technique is the isolation of Taenia taeniaformis larvae, which can be completely purified from infected liver suspensions, representing a 4 X 10(5)-fold enrichment of the parasites, with high recovery, in a single 30 min operation.

Animals↗
PubMed1983

Theory and practice of centrifugal elutriation (CE). Factors influencing the separation of human blood cells.

Centrifugal elutriation (CE) is currently a widely used preparative cell separation technique. In order to optimize the separation of cells that show only small differences in sedimentation velocity, several conditions that might influence the resolution capacity, such as rotor speed, counterflow, jetstream, cell load, density, and viscosity of the elutriation medium, were analyzed. Experiments carried out with human red blood cells (rbc) indicated that selective losses of rbc from the rotor caused by the jetstream, could be prevented if the separations were carried out at high rotor speeds, as predicted by the theory. In addition, high cell loads (5 X 10(8) rbc) resulted in better separations than low cell loads (5 X 10(7) rbc). Human monocytes were separated into subpopulations that differed only about 0.003 g/mL in density, but have virtually the same size. The separation was carried out either by increasing the density or viscosity of the elutriation medium or by decreasing the rotor speed. In all cases similar results were obtained. These results indicated that under optimal conditions CE can be applied for the separation of cells that differ only slightly in sedimentation velocity.

Blood Cells↗
PubMed1993

Oral midazolam premedication in children: the minimum time interval for separation from parents.

To determine the minimum time interval between oral midazolam (0.5 mg.kg-1) premedication and separation from parents that ensures a smooth separation, 30 children were assigned randomly to one of three groups (ten children per group). The groups differed only in the time interval between administration of midazolam and separation from their parents: 10, 20 or 30 min. Heart rate, systolic blood pressure, and sedation and anxiolysis scores were assessed before midazolam premedication (baseline), at the time of separation from parents, and during the application of a face mask at the induction of anaesthesia. We found that heart rate and systolic blood pressure changes were similar for all three groups throughout the study period. Sedation scores at the time of separation from parents and on application of the mask for all three groups were greater than baseline values. Sedation scores at separation did not differ among the three groups. Anxiolysis values did not differ from baseline values at any time for all three groups. We conclude that children may be separated from their parents as early as ten minutes after receiving oral midazolam, 0.5 mg.kg-1.

Administration, Oral↗
PubMed1982

Separation of human peripheral blood monocytes on continuous density gradients of polyvinylpyrrolidone-coated silica gel (Percoll).

A standardized, reproducible two-step method for separation of human peripheral blood monocytes on continuous Percoll gradients has been developed. The first step involves separation of mononuclear cell on Percoll of density 1.075 g/ml and the second step separation of monocytes from lymphocytes on a continuous Percoll gradient with a starting density of 1.075 g/ml for the formation of the gradient. The average yield during a 10 month period of daily routine use has been 74 +/- 17% (mean +/- 1 S.D.), and the average purity 63 +/- 10%. Ninety to 95% of the monocytes are viable after separation as judged from trypan blue exclusion and by ingestion of latex particles and sensitized sheep erythrocytes. The separation takes about 3 h and the total number of monocytes obtained from 40 ml of blood is in the range of 10-15 x 106. The procedure has been reliable with 3-4% separation failures, mainly due to bacterial or fungal growth in Percoll suspension or media. The contaminating cells are exclusively lymphocytes, predominantly T-lymphocytes (90-95%), when citrate is used as anticoagulant. Heparin can not be used as anticoagulant, as there appears to be a dose-dependent formation of thrombocyte aggregates which contaminate the monocytes, and result in poor separation.

Antigen-Antibody Complex↗
PubMed1988

Effects of clonidine and propranolol on separation-induced distress in infant rhesus monkeys.

In primates, separation of an infant from its mother is a naturally occurring stressor resulting in activation of behavioral, endocrine, and autonomic systems. When separated from their mothers, infant rhesus monkeys emit frequent species-typical distress vocalizations ('coos'). In earlier work we demonstrated that opiate and benzodiazepine systems influence the frequency of coos induced by separation in infant rhesus monkeys. The present studies assessed the role of alpha 2- and beta-adrenergic systems in mediating distress vocalizations. We found that the alpha 2 agonist, clonidine (33 and 67 micrograms/kg), reduced activity levels without affecting separation-induced coos. Only at 100 micrograms/kg were distress vocalizations reduced, and this was associated with behavioral sedation. In the same animals, morphine (0.1 and 0.25 mg/kg) selectively reduced distress vocalizations without affecting activity. Thus, the effects of clonidine, 100 micrograms/kg, appear to be due to non-specific sedation. We next assessed whether antagonism of beta-adrenergic receptors reduces separation distress. We administered propranolol over a wide dosage range to a different group of animals and found that a high dose (20 mg/kg) increased separation-induced coos while decreasing the activity levels. That such a high dose was necessary to affect coo vocalizations suggests that effects on vocalizations are due to non-specific effects of the drug. Unlike propranolol, morphine administered to these animals did not affect activity levels but did selectively reduce distress vocalizations. These findings suggest that alpha 2- and beta-adrenergic systems do not specifically mediate separation-induced coos in infant rhesus monkeys. However, as demonstrated in an earlier study, opiate systems have a prominent role.

Animals↗
PubMed1988

Column-based separation of erythrocytes using aqueous polymeric two-phase systems.

Cell separation using aqueous polymeric two-phase systems is well established. For separations of cells having similar partition coefficients a multi-step counter-current distribution procedure has been used. As an alternative strategy, we have developed a column-based technique in which the dextran-rich phase of a dextran-polyethylene glycol (PEG) phase system is immobilized onto derivatized chromatography beads. The PEG-rich phase is used as the eluent. A separation of erythrocytes from different species utilizing an affinity ligand was performed. The following behaviour was observed: (i) no elution occurs below a critical affinity ligand concentration; (ii) cell recovery is proportional to affinity ligand concentration; (iii) elution volume is independent of affinity ligand concentration. The above suggest that no multi-step partitioning occurs. However, the separation achieved is considerably better than in a corresponding single-tube separation. A 1:1 mixture of dog and human erythrocytes was separated to a purity of greater than 98% using the column-based technique. The corresponding optimized single-tube separation gave a maximum purity of 84%.

Animals↗
PubMed2003

Separation anxiety in the elderly.

Separation anxiety has been studied in children and young adults but little is known about this form of anxiety in older people. This study aimed to examine socio-demographic, psychological and physical health correlates of separation anxiety in the elderly. Eighty-six ambulatory subjects aged 62-87 years were recruited from primary medical care practices to participate in this study. The presence of lifetime DSM-IV affective and anxiety disorders was determined by structured clinical interview. Subjects also completed a battery of self-report questionnaires measuring levels of state and trait anxiety, juvenile and adult separation anxiety. Adult separation anxiety scores were moderately correlated with juvenile separation anxiety scores (r= .52, P < .001), trait anxiety (r = .55, P < .001) and state anxiety scores (r = .66, P < .001), as well as younger age (r = .39, P < .001). Higher adult separation anxiety scores were also associated with a lifetime history of any anxiety disorder (t = 3.74, df = 84, P < .001) or any affective disorder (t = 2.12, df = 84, P < .05). However, adult separation anxiety was not associated with increasing age, being widowed, living alone or poorer physical health. Clinicians working with the elderly need to routinely explore this form of anxiety as it may complicate the pattern of presentation of other anxiety and affective disorders, and require specific forms of intervention.

Aged↗
PubMed2002

Dielectrophoretic cell separation and gene expression profiling on microelectronic chip arrays.

Cell membrane dielectric properties of five different cultivated cell lines and human peripheral blood mononuclear cells (PBMC) were determined from dielectrophoretic crossover frequency measurements on a 5 x 5 microelectronic chip array. Based on distinct dielectric property differences between individual cell types, efficient cell separations were achieved by dielectrophoresis on this 5 x 5 array, which included separation of monocytic cells (U937) or human T cell leukemia virus type 1 (HTLV-1) tax-transformed cells (Ind-2) from PBMC, as well as separation of neuroblastoma cells (SH-SY5Y) from glioma cells (HTB). The purity of dielectrophoretically separated cells can be greater than 95%. Expression profiles of IL-1, TNF-alpha, and TGF-beta genes for U937 cells mixed with PBMC before and after the separation were determined by a means of electric field-facilitated hybridization on a 10 x 10 microelectronic chip array. By using the expression levels of pure U937 cells as a control, it was shown that the gene expression profiles of the postseparation cells were significantly different from those of the preseparation cell mixtures. The increase in gene expression levels for U937 cells upon lipopolysaccharide induction could be accurately determined only in the postseparation cells, while the preseparation samples masked these changes. Furthermore, by cultivating the separated HTB and SH-SY5Y cells and measuring expression of the stress-related gene c-fos, dielectrophoretic forces were shown to have little effect on cell survival and stress. The presented approach of using microelectronic chip arrays for both cell separation and gene expression profiling provides a great potential for accurate genetic analysis of specific cell subpopulations in heterogeneous samples.

Cell Line↗
PubMed1998

Percentage of normal sperm heads is significantly increased by Percoll separation of semen.

The purpose of this study was to assess objectively the effects of Percoll separation on human sperm head morphometry. Semen samples were washed and smears were prepared on slides. An aliquot of each sample was centrifuged on a Percoll gradient and spermatozoa were prepared on slides. Dimensions of sperm heads from each sample were assessed by computer-aided sperm head morphometry analysis and manual sperm morphology was assessed for each sample. The percentage of normal sperm heads and morphometric dimensions from washed and post-Percoll separated samples were compared across all men by a paired t-test. Correlations between normal sperm head morphometry and manual sperm morphology were assessed in washed and Percoll-separated samples. The percentage of normal sperm head morphometry was significantly (p < 0.001) higher in Percoll-separated samples than in washed samples (23.6 vs. 12.6%). No differences (p > 0.1) in mean sperm head measurements were detected between washed samples and Percoll-separated samples. Coefficients of variation for mean sperm head measurements were significantly lower in Percoll-separated samples. No correlation (p > 0.1) in percentage normal was found between computer-assisted sperm head morphometry and manual morphology for washed and post-Percoll samples. These results indicate that percentage normal sperm head morphometry is increased by Percoll separation. While sperm head dimensions were unchanged, sample variability was decreased.

Cell Separation↗
PubMed1996

Spousal-residence separation among Chinese young couples.

The factors affecting the residential separation of spouses in China are examined. "Based on the microdata of the 1987 National Population Survey, we find that the variation in spousal-residence separations among Chinese young couples in the mid-1980s is well explained by personal and household factors within a multivariate model. The separations were aggravated by migrations for the reasons of employment or education. Although marriage migrations reduced the number of separations, those who had been married for a short period of time...were more prone to be separated. It is ironic that the higher a person's level of education, the greater the tendency for them to suffer the pain of spousal-residence separation. Household status could also be a very important factor: the lower the household status of a married individual, the more likely that he (or she) would be separated from their spouse."

Asia↗