PubMed Health⌕ Search

Biomedical subjects

L Burk

Publications and source records attributed to L Burk.

5 recordsLinked to original sources
PubMed1979

Distribution of 5'-nucleotidase in human lymphoid tissues.

Low activity of 5'-nucleotidase (5'-ribonucleotide phosphohydrolase, EC 3.1.3.5) in T lymphoblasts may explain the marked sensitivity of this cell to deoxynucleotide accumulation when compared to B lymphoblasts. The relevance of such observations with cultured cells to the normal immune system requires the demonstration of similar differences in the 5'-nucleotidase activity of normal human lymphocyte subpopulations. Sheep erythrocyte (E) rosette-forming cells from normal thymus, tonsil, and peripheral mononuclear cells have 5'-nucleotidase activities of 1.7, 11.3, and 21.2 nmol/hr per 10(6) cells. Non-E-rosette forming cells from the peripheral blood or tonsil have 5'-nucleotidase activity comparable to the higher levels found in the peripheral E-RFC. Increased levels of 5'-nucleotidase activity may be a marker for post-thymic T lymphocytes. T lymphoblasts have 5'-nucleotidase activity similar to values demonstrated for E-RFC in thymus, whereas cultured B lymphoblasts have 5'-nucleotidase activity 15 times greater than that of T lymphoblasts. On the basis of these observations, the 5'-nucleotidase deficiency in congenital agammaglobulinemia has been reevaluated. In these patients the data indicate that peripheral E-rosette forming cells have the enzyme deficiency, demonstrating an abnormality of T lymphocytes in this disorder of immunoglobulin production.

Agammaglobulinemia↗
PubMedDate not supplied

Morbidity and mortality in hemodialysis patients.

Increase in mortality in hemodialysis patients in the United States is a rising concern. In this study, the annual mortality rate from 1981 to 1989 was determined and the morbidity and mortality of 136 patients dialyzed during 1988 was analyzed. All patients were followed with urea kinetics (UK). Patients were divided according to NCDS mapping of BUN and protein catabolic rate (pcr): Group 1, inadequate protein intake (n = 28); Group 2, adequate dialysis (n = 51); Group 3, excessive dialysis (n = 28); Group 4, undefined domain (n = 13); and Group 5, transitional domain (n = 16). The UK parameters measured were midweek predialysis BUN, pcr, and Kt/V. Group 1 by definition had the lowest pcr (0.7 g/kg/day vs. greater than 1.0 in the other groups). Patients in Group 1 had significantly lower BUN, creatinine, hematocrit, and serum albumin. Results of all other laboratory tests were not significantly different. Numbers of hospitalizations and days in the hospital were higher in Group 1. Causes of hospitalization were similar in all groups. Mortality rate was 8% in Group 1 vs. 4.4% in Group 2. Dialysis prescription using UK has maintained the annual mortality rate at about 14% for the past nine years.

Adult↗