Objective To evaluate the effect of ulinastatin on the expression of metabotropic glutamate receptor Ⅱ ( mGluRⅡ) during cerebral ischemia-reperfusion ( I∕R) in rats. Methods Forty-eight male Sprague-Dawley rats, aged 6-8 weeks, weighing 230-280 g, were divided into 3 groups ( n=16 each) by a random number table method: sham operation group (S group), cerebral I∕R group (I∕R group) and ulinastatin group ( U group) . The model of cerebral I∕R injury was established by occluding the right middle cerebral artery using a nylon thread with a rounded tip inserted into internal carotid artery and advanced cranially until resistance was met. Middle cerebral artery occlusion was maintained for 2 h followed by 24-h reperfusion. Ulinastatin 100000 U∕kg was injected via the tail vein immediately after onset of reperfusion in group U. The neurological deficit score ( NDS) was assessed after 24 h of reperfusion. The rats were then sacrificed, and brain tissues were obtained for determination of brain infarction ( by TTC staining) , expression of IκB-α in cerebral ischemic penumbra ( by Western blot) and expression of mGluRⅡ in cerebral ischemic penumbra ( by immunofluorescent staining) . The percentage of cerebral infarct vol-ume was calculated. Results Compared with S group, the NDS and percentage of cerebral infarct volume were significantly increased, the expression of mGluRⅡ in cerebral ischemic penumbra was up-regulated, and the expression of IκB-α in cerebral ischemic penumbra was down-regulated in I∕R and U groups ( P<0. 05). Compared with I∕R group, the NDS and percentage of cerebral infarct volume were significantly de-creased, the expression of mGluRⅡ in cerebral ischemic penumbra was down-regulated, and the expres-sion of IκB-α in cerebral ischemic penumbra was up-regulated in U group ( P<0. 05) . Conclusion The mechanism by which ulinastatin mitigates cerebral I∕R injury may be related to inhibiting the expression of mGluR Ⅱ in cerebral ischemic penumbra of rats.

Objective To evaluate the effect of dexmedetomidine on high-mobility group box 1 protein (HMGB1)/Toll-like receptors (TLRs) signaling pathway during lung injury in septic rats.Methods Twenty-four SPF healthy adult male Wistar rats,aged 15-18 weeks,weighing 200-250 g,were divided into 3 groups (n =8 each) using a random number table:sham operation group (group S),sepsis group (group Sep) and dexmedetomidine group (group D).Dexmedetomidine 25 μg/kg was intraperitoneally injected in D group,while the equal volume of normal saline was given instead in S and Sep groups.Sepsis was produced by cecal ligation and puncture in Sep and D groups.The rats were sacrificed at 24 h after operation,and the right lung was removed for examination of the pathological changes which were scored and for determination of myeloperoxidase (MPO) activity,content of interleukin-1β (IL-1β),IL-6 and tumor necrosis factor-α (TNF-α) in lung tissues (by enzyme-linked immunosorbent assay),wet to dry weight ratio (W/D ratio) and expression of HMGB1,TLR2 and TLR4 in lung tissues (by Western blot).Results Compared with group S,the MPO activity,lung injury score,W/D ratio,content of IL-1β,IL-6,TNF-α and expression of HMGB1,TLR2 and TLR4 were significantly increased in Sep and D groups (P＜0.05).Compared with group Sep,the MPO activity,lung injury score,W/D ratio,content of IL-1β,IL-6,TNF-α and expression of HMGB1,TLR2 and TLR4 were significantly decreased in group D (P＜0.05).Conclusion Dexmedetomidine reduces lung injury through inhibiting HMGB1/TLRs signaling pathway in septic rats.

Objective To evaluate the effect of methylene blue (MB) on hydrogen peroxide (H2O2)-induced apoptosis in macrophages through mitochondria-dependent pathway in mice.Methods Mouse peritoneal macrophage line RAW264.7 cells were cultured in DMEM culture medium containing 10％ fetal bovine serum.Cells were divided into 6 groups (n =24 each) using a random number table method:control group (group C),H2O2 group,prophylactic different concentrations of MB groups (MB1,2 groups) and therapeutic different concentrations of MB groups (MB3.4 groups).H2O2 50 μmol/L was added to the culture medium in group H2O2.MB was added to the culture medium with the final concentrations of 0.1 μmol/L (in MB1 and MB3 groups) and 1.0 μmol/L (in MB2 and MB4 groups) at 30 min before adding H2O2 in MB1.2 groups and 30 min after adding H2O2 in MB3.4 groups.At 24 h of culture or incubation in each group,the cell survival rate was measured by methyl thiazolyl tetrazolium assay,the activity of reactive oxygen species (ROS) in cells was determined with the fluorescent probe,the lactate dehydrogenase (LDH) activity in supernatant was detected by spectrophotometry,the activity of superoxide dismutase (SOD) in cells was detected by colorimetric method,mitochondrial membrane potential (MMP) was measured using rhodamine 123 staining,the content of ATP was determined by an ATP bioluminescent method,the expression of pro-caspase-3 and spliceosomes P20 protein and P 18 protein was detected by Western blot,and cell apoptosis was detected using flow cytometry.Results Compared with group C,the cell survival rate,SOD activity and contents of MMP and ATP were significantly decreased,the ROS activity and activity of LDH in supernatant were increased,the expression of pro-caspase-3 and spliceosomes P20 protein and P18 protein was up-regulated,and early and late apoptosis rates were increased in the other five groups (P＜0.05).Compared with group H2O2,the cell survival rate,SOD activity and contents of MMP and ATP were significantly increased,the ROS activity and activity of LDH in supernatant were decreased,the expression of pro-caspase-3 and spliceosomes P20 protein and P18 protein was down-regulated,and early and late apoptosis rates were decreased in MB1-4 groups (P＜0.05).Compared with group MB1,the cell survival rate was significantly decreased,and the expression of caspase-3 spliceosome P 18 was down-regulated in group MB2,and the cell survival rate and SOD activity were significantly decreased,and the activity of ROS was increased in group MB3 (P＜0.05).Compared with group MB4,the expression of caspase-3 spliceosome P 18 was significantly down-regulated,early and late apoptosis rates were decreased,and the activity of ROS was increased in group MB2,and the activity of ROS was significantly increased in group MB3 (P＜0.05).Conclusion The mechanism by which MB attenuates H2O2-induced oxidative damage to macrophages is related to inhibiting cell apoptosis in macrophages through mitochondria-dependent pathway in mice.

Objective:To summarize the strategy and method for the treatment of critically ill patients with self-made extracorporeal membrane oxygenation (ECMO) system.Methods:A observative study was conducted. Fifty-six patients with ECMO assisted support in Fuwai Central China Cardiovascular Disease Hospital from December 2020 to December 2021 were enrolled. According to the clinical situation of the patients and the wishes of the family, conventional ECMO package (conventional group) or self-made ECMO package (self-made group) was chosen. In the conventional group, the disposable ECMO package was used to install the machine, pre charge and exhaust the air. In the self-made group, the disposable consumables commonly used in extracorporeal circulation during cardiac surgery (including centrifugal pump heads, membrane oxygenation, tubes, connectors, etc.) were used to create a self-made ECMO system. Based on the patient's situation, personalized tube model selection and length control were carried out. The preparation time, auxiliary time, auxiliary method, total pre charge volume, free hemoglobin (FHb) levels after 2 hours of ECMO operation and operating costs, as well as changes in hemodynamics, arterial blood gas analysis, and blood indicators within 48 hours after ECMO placement in the two groups were recorded. The occurrence of adverse events related to the ECMO system during ECMO adjuvant therapy in two groups was simultaneously observed.Results:Fifty-six patients were enrolled finally, with 28 cases in the conventional group and 28 cases in the self-made group, and all successfully completed the operation of ECMO. There was no statistically significant difference in ECMO system preparation time, auxiliary time, auxiliary method, and FHb levels after 2 hours of ECMO operation between the conventional group and the self-made group [preparation time (minutes): 13±4 vs. 15±5, auxiliary time (hours): 287±34 vs. 276±42, veno-arterial ECMO (cases): 22 vs. 24, veno-venous ECMO (cases): 6 vs. 4, FHb after 2 hours of ECMO operation (mg/L): 226±67 vs. 253±78, all P > 0.05]. However, the total pre charge volume and operating costs in the self-made group were significantly lower than those in the conventional group [total pre charge volume (mL): 420±25 vs. 650±10, operating costs (ten thousand yuan): 3.8±0.4 vs. 6.7±0.3, both P < 0.01]. The hemodynamics, arterial blood gas analysis, and blood indicators of patients in the two groups were relatively stable within 48 hours after ECMO operation, and most of the indicators between the two groups showed no statistically significant differences. The hemoglobin (Hb) levels at 12, 24, and 48 hours after the machine transfer in the self-made group were significantly higher than those in the conventional group (g/L: 128.5±23.7 vs. 117.5±24.3 at 12 hours, 121.3±31.3 vs. 109.6±33.2 at 24 hours, 118.5±20.1 vs. 105.2±25.7 at 48 hours, all P < 0.05). Both groups of patients did not experience any adverse event related to the ECMO system, such as membrane pulmonary infiltration, joint detachment, and massive hemolysis, during the ECMO assisted treatment process. Conclusion:When implementing ECMO for critically ill patients in clinical practice, a self-made ECMO system with disposable consumables commonly used in extracorporeal circulation during cardiac surgery can be used for cardiopulmonary function assistance support, thereby saving patients medical costs and alleviating their dependence on disposable ECMO package in clinical practice.