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find Keyword "Hypoxic" 14 results
  • Application of Auditory Brainstem Response in the Hearing Loss and Prognosis Research on Neonatal Hypoxic Ischemic Encephalopathy

    Objective Application of auditory brainstem response (ABR) in the study on the relationship of neonates with hypoxic-ischemic encephalopathy (HIE) and the children with hearing loss and auxiliary determine the prognosis of encephalopathy. Methods We prospectively selected neonates diagnosed as HIE in the department of neonatology of the Chengdu Women and Children Central Hospital from January, 2006 to June, 2008. Neonatal ABR was tested and the prognosis of neonates were observed through 3-year followed up in order to analyze the relationship between HIE severity and the severity of hearing handicap and the relationship between the severity of hearing handicap and prognosis. Statistical analysis was performed using SPSS 18.0. χ2 test was used to compare the rate between groups. Results 40 cases involving 80 ears were included, of which 33 cases accomplished the 3-year follow-up for prognosis. The results showed that, 86.3% HIE neonates had hearing handicap (mainly mild hearing loss, 40.0%). Medium-severe HIE groups had more serious hearing handicap than Mild HIE group with a statistical significance (continuity correction χ2=7.383, P=0.007). ABR results showed that, mild HIE is mainly manifested as I wave PL prolonged or poorly differentiated, accounting for 78.1%; medium - severe HIE are mainly manifested as III and V wave PL prolonged central segment abnormalities, accounting for 95.8%; the hearing threshold no more than 60 dB group had better prognosis than the hearing threshold more than 60 dB group prognosis (Fisher exact probability P=0.001). Conclusion ABR reflects that HIE severity and was positively related to the severity of hearing handicap. The more serious hearing loss in neonates is, the worse prognosis the neonates have. ABR can be used to assist the assessment of the prognosis of neonatal HIE.

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  • Effect of hypoxic preconditioning on rat lungs exposed to simulated high altitude hypoxia

    Objective To investigate the influence of hypoxic preconditioning on pulmonary structure of rats exposed to simulated high altitude hypoxia and to explore the role of hypoxia inducible factor-1α(HIF-1α).Methods Fifty-six Wistar rats were randomly divided into 7 groups(n=8 in each group),ie,a normal control group(N group),an acute hypoxic control group(H0 group),an acute hypoxic group(H1 group),a 3 000 m hypoxic preconditioning group(C3.0 group),a 3 000 m hypoxic preconditioning + acute hypoxic group (C3.1 group),a 5 000 m hypoxic preconditioning group(C5.0 group),and a 5 000 m hypoxic preconditioning + acute hypoxic group(C5.1 group).After treated with hypoxic preconditioning,the animals were exposed to simulated altitude of 6 000 m for 24 hours.Then the protein and mRNA expression of HIF-1α in lung of N,H0,C3.0 and C5.0 groups were assessed by Western blot and RT-PCR,respectively.The lung structure in N,H1,C3.1 and C5.1 groups was observed by light microscope and electron microscope.Results Pulmonary interstitial edema was apparently observed in H1 group,while significantly relieved in two hypoxic preconditioning groups.HIF-1α protein was not detected in rat lungs by Western blot analysis.Compared to N group,the levels of HIF-1α mRNA significantly increased in C3.0 group and C5.0 group(both Plt;0.01).Conclusions Hypoxic preconditioning can relieve hypoxic pulmonary interstitial edema and increase HIF-1α mRNA expression in rat lungs.HIF-1 may be involved in the process of hypoxic preconditioning in rat lungs.

    Release date:2016-09-14 11:56 Export PDF Favorites Scan
  • Effects of Simvastatin on the Collagen Synthesis of Rat Pulmonary Arterial Smooth Muscle Cells Induced by Hypoxia

    Objective To investigate the effects of simvastatin on the collagen synthesis of rat pulmonary arterial smooth muscle cells ( PASMCs ) induced by hypoxia. Methods Under hypoxic condition, rat PASMCs were cultured with different concentrations of simvastatin. Collagen synthesis of PASMCs with or without simvastatin were measured by 3H-proline incorporation assay. The mRNA expression of TGF-β1 and the contents of super oxide dismrtase ( SOD) ,malondialdehyde ( MDA) in mediumwere also measured. Results The incorporation data of 3H-TdR in the hypoxia group was significantly increased as compared with that in the control group ( P lt;0. 01) , and simvastatin significantly reduced the incorporation data of 3H-TdR induced by hypoxia. The expression of TGF-β1 mRNA in the hypoxia group was significantly increased as compared with that in the control group ( P lt; 0. 01 ) , and simvastatin could significantly inhibited hypoxia-induced expression of TGF-β1 mRNA in a dose-dependent manner. Compared with the hypoxia group, the expression of TGF-β1 mRNA decreased by 55% in simvastatin( 10 - 6mol /L) group ( P lt; 0. 01) , and by 70% ( P lt; 0. 01) in simvastatin ( 10 - 5mol /L) group. Compared with the control group, the activity of SOD was reduced and the contents of MDA were increased significantly in the hypoxia group. Simvastatin can increase the activity of SOD and reduced the content of MDA in a dose-dependent manner. Conclusions Simvastatin can decreases collagen synthesis of PASMCs. This effect might be explained that simvastatin can reduce lipid peroxide and expression of TGF-β1 mRNA.

    Release date:2016-09-13 03:51 Export PDF Favorites Scan
  • EFFECTS OF HYPOXIC PRECONDITIONING ON GLUCOSE METABOLISM OF RAT BONE MARROW MESENCHYMAL STEM CELLS

    Objective To study the effects of hypoxic preconditioning on the glucose metabol ism of rat BMSCs and its underlying mechanism so as to provide the theoretical basis for the optimization of the stem-cell based therapy. Methods Density gradient centrifugation method was adopted to isolate rat BMSCs from neonatal SD rats (aged 1-3 days). BMSCs were cultured to 4th passage and divided into 4 groups based on different culture conditions: group A in normoxia condition for 24 hours, group B in 1% O2 for 24 hours, group C in 2-methoxyestradiol (20 μmol/L) for 24 hours before hypoxic preconditioning, and group D in hypoxia-inducible factor 1 (HIF-1) specific siRNA (50 μmol/L) for 12 hours before hypoxicpreconditioning. MTT method was appl ied to evaluate the prol iferation of BMSCs. Biochemical analyzer and Real-timefluorescent quantitative PCR were appl ied to detect the glucose uptake, lactate production, and HIF-1α mRNA and Glut-1mRNA levels of BMSCs. Results MTT showed that the absorbance (A) values were 387.67 ± 58.92, 322.50 ± 50.60, 297.00 ± 53.00, and 286.00 ± 41.00 in groups A, B, C, and D, respectively, showing no significant difference among 4 groups (P gt; 0.05). The levels of glucose uptake and lactate production were higher in group B than in groups A, C, and D, showing significant differences (P lt; 0.05); the levels of groups C and D were higher than those of group A, but showing no significant difference (P gt; 0.05). The mRNA expressions of HIF-1α and Glut-1 elevated significantly in group B when compared with those in group A (P lt; 0.05); groups C and D were significantly lower than group B (P lt; 0.05) and were significantly higher than group A (P lt; 0.05). Conclusion Hypoxic preconditioning can stimulate the glucose uptake and metabol ism of rat BMSCs, whose mechanism is probably related to up-regulating the mRNA expressions of HIF-1α and Glut-1.

    Release date:2016-08-31 05:44 Export PDF Favorites Scan
  • RESEARCH PROGRESS OF HYPOXIA INDUCIBLE FACTOR 1α IN HYPOXIC-ISCHEMIC INJURY

    To review the role of hypoxia inducible factor 1α (HIF-1α) in hypoxic-ischemic injury and its repair, and to analyze the possible mechanisms. Methods Recent l iterature on HIF-1α and its role in hypoxic-ischemic injury was reviewed and analyzed. Results HIF-1α was involved in the hypoxic-ischemic injury of various organs or tissues and their repair processes. Conclusion HIF-1α has a potential to treat common cl inical hypoxic-ischemic injuries and has a promisingfuture for appl ication.

    Release date:2016-09-01 09:07 Export PDF Favorites Scan
  • Shengmai Injection for Hypoxic-ischemic Encephalopathy: A Systematic Review

    Objective To evaluate the efficacy and safety of Shengmai injection for hypoxic-ischemic encephalopathy (HIE). Methods We searched MEDLINE (1966 to February 2007), EMBASE (1980 to February 2007), CBM (1978 to 2006), CNKI (1979 to February 2007), VIP (1989 to February 2007), and handsearched five Journals on Pediatrics. We evaluated features of quality of included studies, including randomization, blinding, allocation concealment and loss of follow-up. Meta-analyses were performed using The Cochrane Collaboration’s RevMan 4.2.8. Results Seven randomized controlled trials were included. The cure rate on day 5 in the Shengmai injection group was higher than in the control group (RR 1.55, 95%CI 1.25 to 1.93), but this rate was similar on day 10 (RR 0.74, 95%CI 0.43 to 1.29). No significant difference in cure rate was noted between the Shengmai injection group and naloxone group (RR 0.88, 95%CI 0.53 to 1.46). No significant differences were observed in mortality (RR0.44, 95%CI 0.16 to 1.19) and mutilation rate (RR 0.58, 95%CI 0.21 to 1.56) between the Shengmai injection group and the control group. For those babies suffering from HIE combined with myocardial damage, Shengmai injection could speed up the recovery of ECG (WMD=–2.02, 95%CI –2.76 to –1.28) and myocardial enzymogram (CK-MB: WMD= –4.78, 95%CI –6.77 to –2.79; CK-BB: WMD=–2.68, 95%CI –4.58 to –0.78). Significant differences in NBNA score were noted between the Shengmai injection group and the control group on day 5 (WMD=4.05, 95%CI 2.47 to 5.63) and day 10 (WMD=3.50, 95%CI 2.26 to 4.74). No fatal side effects were reported. Conclusions Shengmai injection has certain therapeutic values in treating HIE. Shengmai injection can speed up the recovery ECG, CK-BM and CK-BB of HIE patients, especially in those who have myocardial damage. Shengmai injection can also improve the NBNA score. However, because of the low statistical power and high risks for selection bias, performance bias and measurement bias in the included trials, these conclusions need to be interpreted cautiously.

    Release date:2016-09-07 02:12 Export PDF Favorites Scan
  • Fructose 1,6-Diphosphate in Hypoxic lschemic Encephalopathy:A Systematic Review

    Objective To assess the effectiveness and safety of fructose 1,6-diphosphate (FDP) in the treatment of hypoxic ischemic encephalopathy (HIE)patients. Methods Biomedical databases, including MEDLINE (1977 -2004 ), EMBASE(1989- 2004) ,Cochrane Injuries Group trials register, Cochrane Controlled Trials Register, CBMdisk and CNKI (1994- 2005 )were searched. Chnical trials were collecte&Quality assessments of chnical trials were carried out. Randomized controlled trials (RCTs) with mortality and the incidence of cerebral palsy, epilepsy and mental defect were selected for meta-analysis. Results Nine RCTs were included, and all were done in China. None of the 9 RCTs described the method of randomization or allocation concealment. None of the 9 RCTs mentioned wether blindness was use& In Jadad score, 5 trials were scored by 2 and 4 trials were 1. Seven trials were included in the meta-analysis of death, which showed that the obsolute risk (OR) [95% confidence interval (CI)] of death following FDP administration was 0. 50 (95% CI 0. 21 to 1.16). Five RCTs reported the results of follow-up. When intention to treat (ITT) analysis was adopted, the OR of FDP on cerebral palsy was 0. 36 (95% CI 0. 19 to 0. 89), on epilepsy was 0.74 (95% CI 0. 29 to 1.88), and on dementia was 0. 21 (95% CI 0. 06 to 0.70). We didn't conduct sensitivity analysis because no RCTs were of high quality. We didn't identify clinical trials compared with adverse reactions between the two groups. Conclusions The quality of RCTs on FDP for HIE is poor. Because there were no RCTs of high quality available, we can't draw a conlusion. Well-designed RCTs with economic evaluation are urgently needed to evaluate the value of FDP in the treatment of HIE.

    Release date:2016-09-07 02:26 Export PDF Favorites Scan
  • Role of Vascular Endothelial Growth Factor in Protection on Intrahepatic Cholangiocyte Mediated by Hypoxic Preconditioning after Liver Graft

    Objective To investigate the protection on the intrahepatic cholangiocyte mediated by hypoxic preconditioning (HP) after liver transplantation and the role of vascular endothelial growth factor (VEGF). Methods The model of autologous liver transplantation was established, and the rats were divided into 3 groups: autologous liver transplantation group, hypoxic preconditioning before operation group (HP group) and sham operation group. At 6, 12, 24, 48 h after operation, blood samples were collected for examination of the serum total bilirubin (TBIL), direct bilirubin (DBIL) and alkaline phosphatase (ALP), and the expression of VEGF was detected by immunohistochemical method. The pathological changes of cholangiocytes were observed by light microscope. Results As compared with autologous liver transplantation group, the levels of seurm TBIL, DBIL and ALP in HP group were lower (P<0.05), while the expression of VEGF in HP group was higher at the whole process (P<0.05). The degrees of billiary epithelium damage and inflammatory infiltration in autologous liver transplantation group were more severe than those in HP group. Conclusion HP has protective effect on cholangiocytes after liver transplantation, in which VEGF may play an important role.

    Release date:2016-09-08 10:58 Export PDF Favorites Scan
  • Evaluation of Clinical Grading for Neonates with Hypoxic-ischemic Encephalopathy by Diffusion Weighted Imaging

    ObjectiveTo discuss the evaluation of clinical grading for neonates with hypoxic-ischemic encephalopathy (HIE) by diffusion weighted imaging (DWI). MethodsWe retrospectively analyzed the DWI findings of 39 neonates with HIE diagnosed by clinical criteria from December 2009 to July 2013. Abnormal signals were observed for 23 neonates (59%). These neonates were divided into three groups (group A, B and C) according to the shape and range of abnormal signals. Then Kappa test was performed between groups of different clinical grading (light, medium, severe). ResultsFor groups arranged based on abnormal signals and clinical grading, the Kappa value of the consistency test was 0.797 (P < 0.001). ConclusionsDWI negativity cannot exclude the existence of HIE. However, when abnormal signals occur, we can infer the severity in neonates with HIE according to the shape and range of abnormal signals by DWI.

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  • EFFECT OF INTEGRIN β8 ON NEURONAL APOPTOSIS AFTER HYPOXIA ISCHEMIA IN ASTROCYTE/NEURON CO-CULTURE SYSTEM

    ObjectiveTo observe the effect of integrin β8 on the neuronal apoptosis after hypoxia ischemia (HI) in astrocyte/neuron co-culture system. MethodsAstrocytes and neurons were cultured in vitro from cerebral cortex of the P1-3 days Sprague Dawley rats and E16 days fetal rats, respectively. Immunocytochemistry staining was used to identify the purity of cells. Integrin β8 mRNA expression was qualified in the astrocytes at 12 hours, 1 day, and 2 days after HI and reoxygenation (experimental group) and in normal astrocytes (control group) by RT-PCR. Integrin β8 small interering RNA (siRNA) system was established to specifically block astrocyte β8 expression, the efficiency of integrin β8 inhibition was detected by real-time fluorescent PCR. The astrocytes and neurons were co-cultured to established the astrocyte/neuron co-culture system. The neuronal apoptosis was detected with TUNEL in the normal neurons/astrocytes group (co-cultured HI group), the astrocytes infected by integrin β8 siRNA for 2 days/normal neurons group (β8 RNA interference group), and normal neurons in vitro with HI treatment group (HI group) at 1 day after HI and reoxygenation. The normal neurons without treatment as control (control group). ResultsGlial fibrillary acidic protein and neuronal nuclei staining suggested a purity of more than 90% in cultured cells. HI resulted in an increase of integrin β8 mRNA expression at 12 hours after reoxygenation in astrocytes, which peaked at 1 day after reoxygenation, then slowly decreased and remained higher at 2 days, showing significant differences between control group and experimental group and among different time points in experimental group (P<0.05). RNA interference efficiency was most significant at 2 days after astrocytes infected with integrin β8 siRNA (P<0.05). The neuronal apoptosis was significantly increased in HI group, co-cultured HI group, and β8 RNA interference group when compared with control group (P<0.05). But neuronal apoptosis index (AI) was significantly decreased in co-cultured HI group and β8 RNA interference group when compared with HI group (P<0.05). The significant difference of AI was found between co-cultured HI group and β8 RNA interference group (P<0.05). ConclusionIntegrin β8 expression can be induced with hypoxic-ischemic brain damage, leading to decreased AI of neurons and obvious protective effect.

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