RESUMO
Objective To investigate the expression and change of cytoglobin(Cygb)gene on hypoxicischemic brain damage(HIBD).Methods Fifty SD rats of 7days old were divided into four study groups and one control group.The brain tissues were taken at 4hours,12hours,24hours and 48hours after the onset of HIBD.Cygb mRNA was determined by the reverse transcription PCR.One-way method of GraphPad Prism was used for statistics.Results The fragment length of PCR products was identical with experimental design.The expression level of Cygb gene increased at 4h after ischemia,and peaked at 24h.48h after HIBD,the Cygb gene level began to decrease.Conclusion The expression of Cygb in brain tissue increased rapidly after HIBD of newborn rats,suggesting that Cygb may have important function in the protection process of HIBD.
RESUMO
Objective To investigate the protective function of cytoglobin (CYGB) on neurodevelopment of the neonatal rats with hypoxic-ischemic brain damage (HIBD).Methods Healthy seven day old Sprague-Dawlay rats were randomly divided into sham operated group,HIBD group,HIBD+Hemin group and HIBD+zinc protoporphyrin (ZnPP) group.The rats of HIBD,HIBD+Heminand HIBD+ZnPPgroup were given normal saline (0.5 ml),Hemin (50 mg/kg) and ZnPP (50 mg/kg) intraperitoneally respectively,and 12 hours later the left carotid arteries of these rats were ligated and cut off,then hypoxic treated for 2 hours to establish the HIBD models.At 0,24,48 h after HIBD models were established,the expressions of CYGB in the cerebral cortex and hippocampus were observed by immunohistochemistry analysis.At 48 h after HIBD,histopathological changes of brain were observed after HE staining.At 72 h after HIBD,the water content of the brain was observed.At 28 days after HIBD,long term study memory outcome was assessed by Morris water maze.Analysis of variance and Bonferroni test were applied as statistical methods.Results (1)The expression of CYGB in brain(expressed by average gray value which negatively correlated with protein levels):At 0 h,the average gray value of CYGB in the cerebral cortex in HIBD+ Hemin and HIBD group were 166.7±5.1 and 207.1±5.1,which were lower than that in sham operated group (232.3±3.4); but in HIBD+ZnPP group,it was higher (234.9±4.5)(P＜0.05).The average gray value of CYGB was decreased with the extension of hypoxic-ischemic time.At 48 h,the average gray value of CYGB was the lowest in HIBD+Hemin group (126.0± 2.6),followed by HIBD group (150.9±4.5) and HIBD+ZnPP group (163.7±6.3),and the highest was in sham operated group (232.1±5.8)(all P＜0.01).(2) Histopathologic changes of the brain:At 48 h,typical cerebral infarction and hemorrhage were seen in HIBD,HIBD+Hemin and HIBD+ZnPP group,but those were less severe in HIBD + Hemin group than in HIBD + ZnPP group.(3) The water content of the brain:At 72 h,the water content of the left brain in HIBD and HIBD+ZnPP group was (86.5±0.4)％ and (87.3±0.3)％,which was higher than that in right brain [(85.6±0.2)％ and (85.9±0.2)％] (t 12.57 and 11.32,P＜0.01,respectively).(4)Function of the hippocampus:Morris water-maze showed that the longest average escape latency in HIBD+ZnPP group [(76.7±29.8) s],followed by HIBD group [(71.0±30.5) s],HIBD+ Hemin group [(46.7±34.0) s],and sham operated group [(38.3±30.3) s] (all P＜0.01).(5) Long-term histopathologic changes of the brain:At 34 d,brain atrophy rate was the highest in HIBD+ZnPP group [(34.07± 6.75) ％],and then in HIBD group [(29.73± 6.53) ％] and HIBD+ Hemin group [(18.33±4.52)％],which were all higher than that in the sham operated group [(1.55±1.32)％](all P＜0.01).HE staining showed that the hippocampal stratum pgramidale was getting thinner and a large number of neurons was lost in HIBD and HIBD+ ZnPP group,but only a small amout of neurons was lost in HIBD+ Hemin group.Conclusions Increased expression of CYGB in HIBD brain could mitigate the short term and long term pathological injury,and protect the long-term study memory function of the hippocampus.
RESUMO
Objective To investigate the clinical significance in monitoring the dynamic oxygenated parameters in full-term neonates with acute respiratory distress syndrome (ARDS) and its relationship with the prognosis. Methods Forty-one full-term neonates with ARDS from 3 hospitals were divided into two groups according to the clinical outcomes: the death group (n=17) and the survival group (n=24). The parameters of breathing machine and arterial blood gas analysis in these two groups at 2 h, 12 h, 24 h and 36 h after mechanical ventilation were analyzed retrospectively. PaO_2/FiO_2, A-aDO_2, PaO_2/P_AO_2 and RI were calculated and compared between the two groups and within each group among the values of different period. Results Under the circumstance that parameters of breathing machine in the death group were obviously or gradually higher than those in the survival group, PaO_2 in the death group [(10.38?1.45)kPa] was lower than that in the survival group [(11.42?0.98)kPa] only at 36 h (P0.05). In the death group, PaO_2/FiO_2 at 24 h and 36 h [(15.86?4.92)kPa and (15.99?5.62)kPa] was lower than that in the survival group [(21.18?6.48)kPa and (27.12?8.33)kPa](P0.05) . Conclusions PaO2is not a sensitive indicator on the prognosisof NRDSinits early stage . PaO2/Fi O2, A-aDO2, PaO2/PAO2and RI are better than PaO2to reflectthe degree of lung injury ,oxygen exchange rate and therapeutic efficacy . A-aDO2and PaO2/PAO2arevery sensitive in assessing the therapeutic effect and the dynamic monitoring may be helpful injudgingthe prognosis .