ABSTRACT
Objective To study the dynamic changes of cytokines including tumor necrosis factor-alpha (TNF-?),interleukin-6 (IL-6),IL-8 in serum and cerebrospinal fluid (CSF) of asphyxia neonates,and to analyze the relationship between cytokines levels and severity of brain damage and neurological outcome. Methods The concentrations of TNF-?,IL-6,IL-8 in serum and CSF were measured by radioimmunoassay in 63 asphyxia neonates. Neurological development was evaluated at 12 months by children′s developmental scale of china.Results The serum concentrations of TNF-?, IL-6,IL-8 were significantly higher in asphyxiated neonates than those in the controls,and they were correlated with the degree of encephalopathy. The level of serum TNF-? was hig-(hest) at the first day and IL-6 was highest at the third day. There was no marked dynamic changes within 5 days in serum IL-8 level. The concentrations of TNF-?,IL-8 in CSF were higher at the first and the third day.The dynamic changes of IL-6 in CSF were similar in serum and they were positively correlated. The serum concentration of IL-6 in severe brain injury group was much higher than those of normal and mild group.The CSF concentration of IL-6 in severe brain injury group was much higher than that of normal group. The CSF concentration of IL-8 in severe brain injury group was much higher than those of the normal and mild group. Conclusions The concentrations of TNF-?,IL-6 and IL-8 are increased both in serum and CSF in asphyxiated neonates which are correlated with severity of hypoxic-ischemic encephalopathy. Cytokine-mediated inflammatory reactions may participate in the mechanism of hypoxic-ischemic brain injury after asphyxiaion.The concentration of IL-6 in serum and IL-6, IL-8 in CSF are correlated with the neurological outcome.
ABSTRACT
Objective To explore the effect of hyperoxia through mechanical ventilation induced lung injury(VILI) in newborn rabbit.Methods One hundred newborn rabbits aged 1-5 days were randomly divided into 4 groups: with 900 mL/L O2 and mechanical ventilation(MV),group A received high peak inspiratory pressure(HPIP),group B received moderate peak inspiratory pressure(MPIP),group C received low peak inspiratory pressure(LPIP),and group D with no mechanical ventilation with room air.There were 30 rabbits in group A,B,C,10 rabbits in D group.All rabbits were killed at 1,3,6 h after trial respectively.Wet-to-dry weight ratio(W/D) of left lung,and white blood cell(WBC)counts in broncho alveolar lavage fluid(BALF) were measured.The changes of lung histopathology were assessed by hematoxylin-eosin(HE) staining and observed under light microscope.Results Compared with group B and C,the group A demonstrated more pulmonary hemorrhage and pulmonary bullae formation,and the WBC and neutrophils counts in BALF increased and the W/D was higher compared with group B and group C.Meanwhile,alveolar epithelial cellⅡ(AECⅡ) hyperplasy transformed to AECⅠ.In group C,AECⅡswelled and lung tissue edema showed obviously,after 6 hours collagen fibers hyperplasia appeared.Part pulmonary atelectasis was obvious in group C.Conclusions HPIP ventilation can increase lung injury induced by hyperoxia in newborn rabbits,but has minimal effects on MPIP and LPIP ventilation.Pulmonary histopathologic changes participate in the newborn rabbit machine ventilation induced lung injury.