ABSTRACT
In our study, we investigated the intracellular killing ability of granulocytes for healthy and ill subjects by measuring NADH oxidase activity and release of hydrogen peroxide. The protocol methodology measured the hydrogen peroxide released after granulocytes activation by PMA (phorbol 12-myristate 13-acetate) by using the Amplex Red assay, which included counting granulocytes by flow cytometer and measurement of the kinetic curve of NADPH oxidase activity by fluorometer. Two parameters were used to describe the level of granulocyte activity: the initial rate of NADPH-oxidase enzyme activity and the level of hydrogen peroxide released after 20 min of granulocyte activation. The method was applied to measure granulocyte activity in 55 healthy subjects and 30 patients with cancer. It was demonstrated that applied procedure is sensitive for estimation of the disease activity. The granulocyte activity in patients with cancer was compared with the granulocyte activity of healthy subjects and demonstrated the downregulation of NADPH oxidase activity. We showed that granulocytes of cancer patients had inhibited oxidative burst and less NADPH oxidase activity.
Subject(s)
Granulocytes/metabolism , Neoplasms/metabolism , Case-Control Studies , Cell Count , Female , Fluorescent Dyes/metabolism , Granulocytes/drug effects , Humans , Hydrogen Peroxide/metabolism , Kinetics , Male , NADPH Oxidases/metabolism , Neoplasms/classification , Neoplasms/pathology , Oxazines/metabolism , Reproducibility of Results , Respiratory Burst/drug effects , Sensitivity and Specificity , Tetradecanoylphorbol Acetate/pharmacology , Time FactorsABSTRACT
BACKGROUND: Resting energy expenditure (REE) measurements are optimal for accurate assessment of energy requirements and precise provision of parenteral nutrients. We previously observed significant reduction in REE during a 4-week period in children undergoing hematopoietic stem cell transplantation (HSCT). The goal of this study was to determine if weekly REE measurements could accurately represent changes in REE in the peritransplant period compared with a more frequent standard of daily measurements. METHODS: Data are presented from a previously described cohort of 37 children undergoing HSCT. We performed weekly indirect calorimetry on 25 patients; of those 25, we performed daily measurements on a convenience sample of 5 children. The time course of REE was analyzed in each sample by repeated measures regression. RESULTS: The REE trend of the 20 weekly participants was similar to that of the 5 daily participants, reaching about 80% of predicted REE at 4 weeks posttransplant, with an average decline of 3.4% per week during 4 weeks. CONCLUSION: The results suggest that weekly REE measurements accurately characterize REE changes 4 weeks after HSCT compared with daily measurements. Characterization of these trends using weekly measurements may help guide clinical and nutrition care of these patients.
