ABSTRACT
Surfactant comprises phosphatidylcholine (PC) together with anionic phospholipids, neutral lipids, and surfactant proteins SP-A to-D. Its composition is highly specific, with dipalmitoyl-PC, palmitoyl-myristoyl-PC, and palmitoyl-palmitoleoyl-PC as its predominant PC species, but with low polyunsaturated phospholipids. Changes in pulmonary metabolism and function in response to injuries depend on their duration and whether adaptation can occur. We examined in rats prolonged (7 days) versus acute (2 days) exposure to non-lethal oxygen concentrations (85%) with respect to the composition and metabolism of individual lung phospholipid molecular species. Progressive inflammation, structural alteration, and involvement of type II pneumocytes were confirmed by augmented bromodeoxyuridine incorporation, broadening of alveolar septa, and increased granulocyte, macrophage, SP-A, and SP-D concentrations. Surfactant function was impaired after 2 days, but normalized with duration of hyperoxia, which was attributable to inhibition but not to alteration in SP-B/C concentrations. Phospholipid pool sizes and PC synthesis by lung tissue, as assessed by [methyl-(3)H]-choline incorporation, were unchanged after 2 days, although after 7 days they were elevated 1.7-fold. By contrast, incorporation of labeled PC into tissue pools of surfactant and lung lavage fluid decreased progressively. Moreover, concentrations of arachidonic acid containing phospholipids were augmented at the expense of saturated palmitoyl-myristoyl-PC and dipalmitoyl-PC. We conclude a persisting impairment in the intracellular trafficking and secretion of newly synthesized PC, accompanied by a progressive increase in alveolar arachidonic acid containing phospholipids in spite of recovery of acutely impaired surfactant function and adaptive increase of overall PC synthesis.
Subject(s)
Hyperoxia/metabolism , Lung/metabolism , Pulmonary Surfactant-Associated Proteins/metabolism , Animals , Arachidonic Acid/metabolism , Bronchoalveolar Lavage Fluid , Cell Proliferation , Granulocytes/metabolism , Macrophages, Alveolar/metabolism , Male , Phagocytes/metabolism , Phospholipids/metabolism , Rats , Rats, Sprague-Dawley , Surface Tension , Time FactorsABSTRACT
GOALS: In this multicenter crossover study, our aim was to evaluate the efficacy and acceptance of acupuncture as a supportive antiemetic approach during highly emetogenic chemotherapy in pediatric oncology. PATIENTS AND METHODS: Eleven children receiving several courses of highly emetogenic chemotherapy for treatment of solid tumors were included. Randomization allocated patients to start chemotherapy either with antiemetic medication plus acupuncture or antiemetic medication alone. During all study courses, patients continued to receive their programmed and additional antiemetic medication as needed. Acupuncture was given at day 1 of chemotherapy and at subsequent days on patient's demand. The amount of baseline and additional antiemetic medication during chemotherapy was documented. Patients maintained a daily diary of vomiting episodes and completed an evaluated nausea score at the end of every course. Their body weight was taken before and after a chemotherapy course. MAIN RESULTS: Twenty-two courses with or without acupuncture were compared. The benefits of acupuncture in adolescents with respect to the reduction of additional antiemetic medication were observed. Acupuncture enabled patients to experience higher levels of alertness during chemotherapy and reduced nausea and vomiting. Except for needle pain, no side effects were noted. Patient's acceptance of acupuncture was high. CONCLUSION: Our data indicate that acupuncture might reduce antiemetic medication and episodes of vomiting in pediatric oncology.
