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)

To study the mechanism of imparied insulin secretion from rat fetal islets, the insulin responsiveness of islets from fetuses (day 21.5 of gestation) to a variety of secretagogues was compared with that of adult rat islets. Forskolin (30 microM)-induced insulin release from fetal and adult islets was 2.7-and 2.5-fold higher, respectively, than that from islets treated with 5.6 mM glucose alone. The effects of 12-O-tetradecanoyl phorbol-13-acetate (TPA) (200 nM) were also similar in fetal and adult islets. Thus, the responsiveness to forskolin and TPA showed no significant difference in adult and fetal islets. A synergistic effect of combinations of various insulin secretagogues was observed in adult islets; however, a weak synergistic effect was present with gliclazide plus TPA only in fetal islets. After islets were cultured in RPMI 1640 (containing 11.1 mM glucose), gliclazide-, forskolin-, and TPA-induced insulin release reached the levels obtained in adult islets. However, the synergistic effect of gliclazide and TPA disappeared after culture of the islets. These results suggest that the poor insulin secretion from fetal islets is not due to a defect in the activating system of either cAMP or C-kinase, but to the immaturity of the interaction of those messenger systems.
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PMID:Rat fetal islets as a useful model for the study of insulin release failure. 332 83

Monocytes as antigen-presenting cells play an important role in host defence. There are several cytokines affecting monocyte function. We demonstrate that both adult and cord blood monocytes constitutively express hepatocyte growth factor (HGF) receptor, MET. HGF significantly down-regulated MET expression of adult blood monocytes, compared with cord blood monocytes, when cultured either in RPMI-1640 containing 10% FBS or serum-free medium. Surface levels of MET correlated with c-met mRNA levels both in adult and cord blood when cultured. MET expression was down-regulated by treating with actinomycin D or cycloheximide. HGF stimulated DNA synthesis of adult monocytes, but not cord blood. HGF enhanced antigen-presenting capacity of adult blood monocytes but not cord blood monocytes. HGF up-regulated HLA class I expression in adult monocytes but not in cord blood monocytes. The current results suggest that the failure of cord blood monocytes to respond to HGF may be responsible, in large part, for their functional immaturity.
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PMID:Differential responsiveness of cord and adult blood monocytes to hepatocyte growth factor. 1152 13

The reduced incidence of graft-vs.-host disease following umbilical cord blood (CB) transplantation may be related to the functional immaturity of newborn T cells expressing mainly the naive CD45RA phenotype. Expansion of CD4(+) CD45RA(+) T cells using cytokines may benefit neonates and infants with human immunodeficiency virus (HIV) infection, as a preferential decline in CD4(+) CD45RA(+) cells has been noted as HIV disease progresses. The aim of the study was to investigate the effect of interleukin (IL)-15, a novel cytokine similar to IL-2 in biological activities, on CD45RA/RO expression and apoptosis in umbilical cord blood (CB) and adult peripheral blood (APB) mononuclear cells (MNCs). Prior to culture, CB MNCs contained a greater number of CD4(+) CD45RA(+) cells and fewer CD4(+) CD45RO(+) cells than did APB MNCs. When incubated with RPMI-1640 containing 10% fetal calf serum for 7 days, the percentage of CD45RA(+) cells within CD4(+) T cells (%CD45RA(+)/CD4(+)) significantly decreased compared to that of fresh CB MNCs. IL-15 exerted a dose-dependent increase of %CD45RA(+)/CD4(+) and a corresponding decrease of %CD45RO(+)/CD4(+) in CB MNCs, an effect not observed with APB MNCs treated with IL-15. The percentages of CD45RA(+) and CD45RO(+) expression within CD8(+) cells, however, were not influenced by IL-15, in either CB or APB MNCs. A greater number of CB MNCs underwent apoptosis than did APB MNCs after 7 days of culture in RPMI-1640 containing 10% fetal calf serum. IL-15 did not inhibit apoptosis but induced proliferation comparable to that achieved in APB MNCs. The ability of IL-15 to preferentially enhance the proliferation of CD4(+) CD45RA(+) cells in CB MNCs suggests a role for immunomodulative therapy in HIV-infected newborns and infants.
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PMID:Interleukin-15 enhances CD4(+) CD45RA(+) expression on umbilical cord blood mononuclear cells. 1155 15

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