OBJECTIVE To determine the role of endogenous carbon monoxide(CO) in oxidant-mediated organ injury following limb ischemia-reperfusion (I/R) in rats. METHODS: Sixty-four SD rats were divided into 4 groups: Sham group, Sham + zinc protoporphyrin (ZnPP, an inhibitor of heme oxygenase activity), 2-hour ischemia followed by 4-hour reperfusion (I/R) group and I/R + ZnPP group. Carboxyhemoglobin (COHb) level in the artery blood, malondialdehyde (MDA) content and superoxide dismutase (SOD) activity in the lung, heart, liver and kidney were detected. The 24-hour survival rate of rats was studied. RESULTS: Compared with the sham group, the COHb level and MDA content significantly increased, while the SOD activity and the survival rate significantly decreased in I/R group (P lt; 0.05). Compared with the I/R group, MDA content significantly increased, while the SOD activity, the 24-hour survival rate and COHb level significantly decreased in I/R + ZnPP group (P lt; 0.05, respectively). CONCLUSION: Limb I/R could lead to the oxidant-mediated multiple organ injury accompanied by the increase of CO level which play an important role in the defense against I/R-induced remote multiple organ injury in rats.
Objective To investigate the preventive effect of rapid preoxygenation technique on hypoxia caused by respiratory depression during outpatient obstetrics-gynecology operations. Methods According to a computer-generated random sequence, a total of 120 ASA I-II patients undergoing outpatient obstetrics-gynecology operations were randomly allocated into the trial group or the control group, 60 in each group. Patients in the control group received preoxygenation with tidal volume breathing. Patients in the trial group received preoxygenation with eight deep breaths (DB) in 1 min before anesthesia. All patients were induced with midazolam 1 mg, fentanyl 1μg /kg and propofol 2 mg/kg, and were maintained with propofol when needed. The following parameters were observed, including the incidences of respiratory depression and apnea, the onset time of anesthesia, the total doses of propofol as well as the changes in PetCO2 and SpO2. Results No significant differences were observed in demographic characteristics, the onset time of anesthesia, the total doses of propofol, and the incidences of respiratory depression and apnea between the two groups (P gt;0.05). However, the SpO2 in the control group was decreased significantly with a higher incidence of hypoxia (Plt;0.05). Conclusions Rapid preoxygenation technique may increase the oxygen reserves and improve the tolerance to hypoxia. It is effective in avoiding hypoxia caused by respiratory depression and apnea during outpatient obstetrics-gynecology operations.
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.
ObjectiveTo compare the effects on the osteogenesis of bone marrow mesenchymal stem cells (BMSCs) between hypoxia and hypoxia mimetic agents dimethyloxalylglycine (DMOG) under normal oxygen condition. MethodsBMSCs were isolated and cultured from healthy 3-4 weeks old Kunming mouse. Cell phenotype of CD29, CD44, CD90, and CD34 was assayed with flow cytometry; after osteogenic, adipogenic, and chondrogenic induction, alizarin red staining, oil red O staining, and toluidine blue staining were performed. The passage 3 BMSCs were cultured under normal oxygen in control group (group A), under 1%O2 in hypoxia group (group B), and under normal oxygen and 0.5 mmol/L DMOG in DMOG intervention group (group C). BMSCs proliferation was estimated by methyl thiazolyl tetrazolium assay at 1, 2, 3, and 4 days. Alkaline phophatase (ALP) expression was determined at 7 and 14 days after osteogenic induction. Western blot was employed for detecting hypoxia inducible factor-1α(HIF-1α) at 24 hours. Real time fluorescence quantitative PCR was employed for detecting the mRNA expression of runt-related transcription factor 2 (RUNX2) and Osterix at 3 and 7 days. Alizarin red staining was applied to assess the deposition of calcium tubercle at 21 days. ResultsThe BMSCs presented CD29(+), CD44(+), CD90(+), and CD34(-); and results of the alizarin red staining, oil red O staining, and toluidine blue staining were positive after osteogenic, adipogenic, and chondrogenic induction. No significant difference in BMSCs proliferation was observed among 3 groups at 1 day (P>0.05); compared with group A, BMSCs proliferation was inhibited in group C at 2, 3, and 4 days, but no significant difference was observed (P>0.05); compared with group A, BMSCs proliferation was significantly promoted in group B (P < 0.05). At each time point, compared with group A, the ALP expression, HIF-1αprotein relative expression, and mRNA relative expressions of RUNX2 and Osterix were significantly up-regulated in groups B and C (P < 0.05); compared with group B, the ALP expression, the RUNX2 and Osterix mRNA relative expression were significantly up-regulated in group C (P < 0.05); compared with group C, the HIF-1αprotein relative expression was significantly up-regulated in group B (P < 0.05). The alizarin red staining showed little red staining materials in group A, some red staining materials in group B, and a large number of red staining materials in group C. ConclusionHypoxia can promote BMSCs proliferation, DMOG can not influence the BMSCs proliferation; both hypoxia and DMOG can improve osteogenic differentiation of BMSCs, and DMOG is better than hypoxia in improving the BMSCs osteogenesis.
We assayed the levels of free radical and scavenger in the blood and lens of streptozotocin-in-duced diabetic SD rats, and found that the levels of lipoperoxide(LPO),MDA were higher than that of normal SD rats, and the total superoxygen dismutase (T-SOD), Cu-Zn-SOD) were lower that that of normal rats ( P lt;0.01 ). Simultaneous injection of streptozotocin and large dose of SOD could no avoid the occurence of diabetes mllitus, but did improve the metabolism of free radical in blood and lens. Hence, we think that large dose of SOD might be effective in preventing to development of diabetic cataract which is related to deterioration of free radical metabolism. （Chin J Ocul Fundus Dis,1994,10:25-27）
Objective The usefulness of measurement of nuclear DNA content elevation for diagnosis of early hepatocellular carcinoma was evaluated by a study of 186 patients with liver cirrhosis. Methods Nuclear DNA content was measured using an automatic image analysis system.Results ①Hepatocellular carcinoma was found in 37 patients during 10 years follow-up, the cumulative incidence of hepatocellular carcinoma was 19.89%. ②The incidence of hepatocellular carcinoma increased with the increase of the patterns of α-fetoprotein (AFP), 5c exceeding rate (5cER), FORM PE, but positive predictive value of 5cER was the highest of three parameters, the difference among all groups was significant by the χ2 test (Ｐ＜0.05). ③When 5cER joined AFP for monitoring development of hepatocellular carcinoma, the incidence of hepatocellular carcinoma was 72.00%, which was significantly higher than that of 5cER or AFP alone, the difference between groups was highly significant (Ｐ＜0.01). Conclusion Patients who had 5cER levels of 3%-5% or more, who had transient increases in 5cER or who had both, should be treated as being in a super-highrisk group for hepatocellular carcinoma. Frequent and careful examination by ultrasonography of such patients is recommended. It is important that measurement of 5cER join with AFP in cirrhotic patients monitored for early development of hepatocellular carcinoma.
ObjectiveTo investigate the influence of Ataxia-telangiectasia mutated (ATM) activation on cellular oxidative stress induced by high glucose in bovine retinal capillary endothelial cells(BRECs). Methods The BRECs were treated by different culture medium with various glucose concentrations (5 mmol/L glucose, 30 mmol/L glucose, 30 mmol/L glucose+10 μmol/L KU55933) as normal glucose group, high glucose group and treatment group respectively.After the cells incubated for 48 hours, the protein expression of ATM, P-ATM, Mitogen-Activated Protein Kinase P38(P38), P-P38, Extracellular signal-regulated kinases(ERKs), P-ERKs was detected by Western blot; cellular ROS level was detected by Reactive Oxygen Species Assay Kit; propidium iodide/Hoechst staining was used for analysis of apoptosis; the expression of vascular endothelial growth factor (VEGF) in the supernatant was determined by Enzyme-Linked Immunosorbent Assay (ELISA); the paracellular permeability between endothelium cells was detected by FITC-dextran. ResultsCompared with the protein level of P-ATM, P-P38 and P-ERKs in high glucose group increased. Especially, P-P38, P-ERKs expressed much more than in high glucose group. The secretion of VEGF in high glucose group was higher than that in the normal glucose group but less than that in treatment group. The same tendency existed in ROS assay, apoptosis assay and paracellular permeability measuring. ConclusionsHigh glucose induced altered activation of ATM which might play a protective role in cellular oxidative stress. Deficiency of ATM might lead to ROS explosion, cell apoptosis and dysfunction of endothelial barrier. The mechanism might be associated with P38, ERKs and VEGF.