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581.
Density gradient separation of peripheral blood stem cells: comparison of an automated cell processing device and manual methods 总被引:1,自引:0,他引:1
Peripheral blood stem cells were collected from normal donors by leukapheresis on a cell separator. The leukapheresis product contained 1.5 x 10(10) mononuclear cells (MNCs) and was divided into two aliquots that underwent either automated or manual density gradient separation with ficoll-hypaque and subsequent washing. In the automated process, recovery of MNCs was 85 percent, reduction in platelet content was 64 percent, and the final hematocrit (Hct) was less than 1 percent. The manual separation resulted in 76-percent MNC recovery, a 79-percent reduction in platelet content, and a final Hct of less than 1 percent. The purified MNCs were then placed in methylcellulose culture at a concentration of 4 x 10(5) MNCs per mL. Quadruplicate 1-mL aliquots were cultured, and colonies were counted and classified on Day 14. Comparison of automated and manual ficoll-hypaque separations demonstrated no differences in the total, erythroid, or granulocyte-macrophage colony numbers. The cell processor used is fast, reliable, uncomplicated, and provides a sterile product containing progenitor cells that are not adversely affected by the automated ficoll-hypaque separation. 相似文献
582.
We present cell cycling and functional evidence that the CD34+CD38- immunophenotype can be used to define a rare and primitive subpopulation of progenitor cells in umbilical cord blood. CD34+CD38- cells comprise 0.05% +/- 0.08% of the mononuclear cells present in cord blood. Cell cycle analysis with the fluorescent DNA stain 7- aminoactinomycin D showed that the percentage of CD34+ cells in cycle directly correlated with increasing CD38 expression. CD34+CD38- cord blood cells were enriched for long-term culture-initiating cells (LTCIC; cells able to generate colony-forming unit-cells [CFU-C] after 35 to 60 days of coculture with bone marrow stroma) relative to CD34+CD38- cells. In an extended LTCIC assay, CD34+CD38- cells were able to generate CFU-C between days 60 and 100, clearly distinguishing them from CD34+CD38+ cells that did not generate CFU-C beyond day 40. When plated as single cells, onset of clonal proliferation was markedly delayed in a subpopulation of CD34+CD38- cells; clones (defined as > 100 cells) appeared after 60 days of culture in 2.9% of CD34+CD38- cells. In contrast, 100% of CD34+CD38+ cells formed clones by day 21. Although the CD34+CD38- immunophenotype defines highly primitive populations in both bone marrow and cord blood, important functional differences exist between the two sources. CD34+CD38- cord blood cells have a higher cloning efficiency, proliferate more rapidly in response to cytokine stimulation, and generate approximately sevenfold more progeny than do their counterparts in bone marrow. 相似文献
583.
584.
Anghelescu DL De Armendi AJ Thompson JW Sillos EM Pui CH Sandlund JT 《Paediatric anaesthesia》2002,12(2):168-170
We report the development of stridor and dysphagia in a 5-month-old-infant with acute lymphoblastic leukaemia after the administration of four weekly doses of vincristine during induction therapy. Because direct laryngoscopy revealed bilateral vocal cord paralysis, the patient underwent elective intubation. Extubation was performed 7 days later, after direct laryngoscopy confirmed recovery of vocal cord mobility. Vincristine-induced bilateral recurrent laryngeal nerve paralysis is a rare but potentially life-threatening complication. Therefore, it should be suspected when stridor is present, and clinicians should consider visualization of the airway to establish the cause of upper airway compromise in infants receiving vincristine. 相似文献
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586.
HZ Abdel‐Hafez E‐EM Mohamed AA Abd‐Elghany 《Journal of the European Academy of Dermatology and Venereology》2010,24(6):704-708
Background Oxidative stress (OS) results from an imbalance between free radical generating and scavenging systems. The end product of lipid peroxidation, malondialdehyde (MDA) serves as a marker of cellular damage. Superoxide dismutase (SOD) traps free radicals and acts as a free radical scavenging system. Objective To study OS indices in paucibacillary (PB) and multibacillary (MB) leprosy in tissues and blood. Materials and methods The study group comprised untreated PB patients (n = 14), untreated MB patients (n = 18) and normal human volunteers (n = 20). SOD activity, MDA level and MDA/SOD ratio were estimated in both blood and tissue. Results Compared with controls, SOD activity in tissues decreased significantly in both PB and MB patients, while SOD activity in erythrocytes decreased significantly only in MB. In addition, MDA levels increased significantly in tissues of both PB and MB patients. Moreover, the mean level of MDA in plasma of MB patients was significantly higher, whereas there was no significant difference in that of PB patients. This study showed significant increase in OS index (MDA/SOD ratio) in tissue of PB and MB patients and in blood of MB patients only, whereas there was no significant difference in OS index in blood of PB patients compared with that in the controls. Conclusion Oxidative stress was observed in both tissues and blood of MB patients and in tissues of PB patients, denoting its crucial involvement in the pathogenesis of leprosy. This can constitute an important tool in prognosis, treatment and control of leprosy. 相似文献