Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: KEGG:D02003 (NBT)
 1,323 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The mechanism by which resistance to 1,25 dihydroxyvitamin D3 (1,25-(OH)2D3) occurs in patients with chronic renal failure was studied. This agent induces differentiation and 1,25-(OH)2D3-24-hydroxylase activity in the mitochondria of the human promyelocytic leukemia cell line, HL-60, via a steroid-hormone receptor mechanism. HL-60 cells were cultured in RPMI 1640 medium supplemented with 10% normal or uremic serum. Treatment of these cells with 10(-8)M 1,25-(OH)2D3 for 5 days in a medium containing 10% uremic serum from 4 patients with chronic renal failure resulted in a maturation of the cells amounting to 30.3 +/- 18.7% (mean +/- SD) and 32.5 +/- 11.2%, as obtained by NBT reduction assay and NSE assay, respectively. These values were significantly lower than those obtained with 10% serum from 3 normal controls (66.6 +/- 12.8%, 58.3 +/- 10.9%, p less than 0.02). The treatment of HL-60 cells with 1,25-(OH)2D3 in a mixture of 5% normal plus 5% uremic serum caused cell differentiation to an extent similar to that in 10% uremic serum, which suggests the presence of a substance(s) having 1,25-(OH)2D3-inhibitory activity in the uremic serum. Exposure of HL-60 cells to uremic serum significantly impaired their responsiveness to 1,25-(OH)2D3 as assessed by the induction of the cell's ability to hydroxylate the C-24 position of 1,25-(OH)2[3H]D3. The mechanism by which uremic serum confers an impaired cellular response to 1,25-(OH)2D3 seemed to be due, in part, to a decrease in 1,25-(OH)2D3 receptor levels. A significant positive correlation was observed between intracellular cAMP levels and 1,25-(OH)2D3-induced HL-60 cell maturation. In summary, the mechanism by which uremic serum confers 1,25-(OH)2D3 resistance upon HL-60 cells seemed to be due to the presence of 1,25-(OH)2D3-inhibitory activity in uremic serum, which may modulate cellular responsiveness to 1,25-(OH)2D3 by such mechanisms as reducing 1,25-(OH)2D3 receptor levels in the cells, in part through alteration in cAMP metabolism.
 ...
PMID:Effects of uremic serum on 1,25-dihydroxyvitamin D3-induced differentiation of a human promyelocytic leukemia cell line, HL-60. 166 75

In 10 patients with chronic renal failure treated with haemodialyses (HD) T and B cell populations were determined in peripheral blood, together with immunoglobulin concentration and NBT test in the first two hours of the procedure using cuprophan and cellulose acetate dialysers. It was found that the per cent proportions of T4, T8 and T11 were not significantly changed. The proportions of B cells with sIg, sIgG, sIgM, sIgA were not significantly altered during HD with cuprophan dialysers. The per cent of B cells with sIg, sIgG decreased significantly during HD with cellulose acetate dialysers. The per cent proportions of active and late E rosettes decreased significantly, the per cent of stable E rosettes rose significantly, while that of EAC rosettes was not significantly changed in the initial HD period with the use of both dialyser types. IgG concentration rose significantly in the initial period of HD with either dialyser, while there was no significant change in the concentration of IgA and IgM. The value of the NBT test was not altered significantly during HD with either dialyser type.
 ...
PMID:[Subpopulations of t and B lymphocytes, rosette tests, levels of immunoglobulins in peripheral blood and NBT test in the initial period of hemodialysis conducted with cuprophan or cellulose acetate dialysers in patients with chronic renal failure]. 781 71

Having in mind the fact, that in patients with secondary hyperparathyroidism induced by chronic renal failure, phagocytic capability of leukocytes is supressed, we attempted to investihate the role of parathormone in it. The study included 6 hemodialysed and 5 healthy volunteers. The degree of phagocyosis was determined according to the HBT test on polymorphonuclear leukocytes (PMNL), before, and 7 and 60 days following the subtotal parathyroodectomy. In all patients, value of NBT test was highly significantly decreased. Following the surgical procedure the increase was significant, however it remained significantly lower when compared to the controls. We have concluded that inhibitory role of parathormone in PMNL phagocytosis was significant, however, in such patients the inhibition was contributed by other factors, as well.
 ...
PMID:[The influence of parathyroidectomy on phagocytic capability of polymorphonuclear cells in patients on hemodialysis]. 1817 78