Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0029713 (immaturity)
 4,335 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Calcium and sodium permeability of erythrocytes from patients with untransfused alpha- or beta- thalassemia major has been studied and compared to mature erythrocytes or control cells with comparable reticulocytosis. Isotopic Na(+) influx was increased a mean fourfold greater than normals and threefold greater than reticulocyte rich control. Passive net leak of Na(+) into thalassemic cells incubated with ouabain was also increased corresponding to their greater (22)Na(+) influx. Erythrocyte Na(+) and K(+) concentrations and cell water content per unit volume of cells were normal. Quantitation of active cation pumps in the cell membrane by the technique of [(3)H]ouabain binding showed a 2.6- to 9.9-fold increase above normal. Inward Ca(2+) movement was studied in cells with absent Ca(2+) pumping produced by depletion of either ATP or Mg(2+)-ions. Calcium uptake by ATP depleted thalassemic cells was increased 12-fold above normals and 3.6-fold above reticulocyte-rich controls. The Ca(2+) uptake by Mg(2+)-depleted thalassemic cells was also increased above normal confirming that erythrocyte Ca(2+) permeability is increased in this disease. Osmotic fragility measurements show that the surface area to volume ratio of thalassemic erythrocytes was increased by 15 to 25% above mature erythrocytes. The increased passive cation permeability of thalassemic erythrocytes cannot be explained by either reticulocytosis or an increased surface area to volume ratio of these cells. Moreover, erythrocyte Na(+) and Ca(2+) influxes in congenital dyserythropoietic anemia (CDA type 2) were increased 2- and 14-fold, respectively, above normal. The increased cation fluxes and cation pump numbers in thalassemic and congenital dyserythropoietic anemia erythrocytes are consistent with the hypothesis of membrane immaturity arising from rapid marrow transit times, a concept previously advanced to explain the persistence of i-antigen on these cells.
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PMID:Increased erythrocyte cation permeability in thalassemia and conditions of marrow stress. 720 77

Haematopoietic stem cell transplantation is indicated in several haematologic and genetic diseases, the most notable being aplastic anemia and leukemias. Bone marrow has been the traditional source of these cells. Human umbilical cord blood (UCB) has recently become an alternative source of haematopoietic stem cells for transplants. The advantages of cord blood include noninvasive collection without risk to mother and neonate, low risk of viral infection, and immunologic immaturity of cord cells. Single umbilical cord blood donation is usually sufficient for transplantation to adult recipients. Additionally, banking of HLA-typed UCB appears valuable in patients lacking a family donor. This study has focused on basic "perinatological" parameters of umbilical cord blood: average volume of single donation UCB and initial storage conditions before isolation of haematopoietic stem cells. Additionally, the mean content of CD34+ haematopoietic stem cells in leukocyte, lymphocyte and mononuclear cell fractions was established. Correlations between levels of so-called pro-inflammatory cytokines (present in cord blood serum) and number, viability and clonogenicity of cord blood mononuclear cells were checked. UCB samples were obtained by "open" collection during vaginal deliveries and cesarean sections. The collected blood was stored in solutions of anticoagulants (ACD, CPDA-1, heparin) and culture media (PBS, Iscove medium, RPMI), during several time intervals (0-1 h, 1-6 h, 6-12 h, 12-24 h) and at two temperatures (+4 degrees C, ambient). UCB volumes, as well as MNC counts, correlated with delivery type, placental weight, neonatal body weight and duration of pregnancy. The concentration, viability and clonogenicity of MNCs were assessed after collection and storage. The subpopulation of CD34+ haematopoietic stem cells was isolated from MNCs using monoclonal antibodies and magnetic-based separation. The number, viability and clonogenicity of CD34+ cells were evaluated. Subsequently in some samples, the concentration of proinflammatory cytokines (IL-1 alpha, IL-1 beta, IL-6, IL-8, and TNF-alpha), number of mononuclear cells and in vitro clonogenicity of myeloid progenitors (CFU-GM) were determined. It was found that the collected blood volume depended on neonatal body weight (Fig. 1). Umbilical blood could be stored either at ambient temperature (Fig. 4) or +4 degrees C (recommended because of reduced risk of infection) for up to 24 hours in RPMI solution (Fig. 5) with heparin (Fig. 2, 3). CD34+ cell count correlated with mononuclear cell count only (Fig. 6). A negative correlation between the number of mononuclear cells and concentration of TNF-alpha was revealed (Fig. 7), as well as between the number of detectable CFU-GM and concentration of IL-1 beta (Fig. 8). In conclusion, UCB collection and short-term storage is a safe and simple method for graftable haematopoietic stem cell recovery. Save for IL-1 beta and TNF-alpha, cytokine levels did not correlate with the studied parameters of umbilical cord blood.
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PMID:[Improved method for delivery room collection and storage of human cord blood cells for grafting]. 1251 5