ObjectiveTo investigate the mechanism of action of remifentanil （RMZL） in alleviating lung ischemia-reperfusion injury （LIRI） in rats by inhibiting pyroptosis through modulating hypoxia inducible factor-1α （HIF-1α）/NOD-like receptor thermal protein domain associated protein 3 （NLRP3） pathway. MethodsRats were stochastically assigned into Control group， LIRI group， RMZL low-dose group， RMZL medium-dose group， RMZL high-dose group， and RMZL high-dose+HIF-1α activator dimethyloxallyl glycine （DMOG） group， with 18 rats in each group. Rats in Control group only had their left pulmonary hilum free and did not undergo ischemia-reperfusion treatment. Except for the Control group， LIRI models were constructed in all other groups. Rats in LIRI group were intraperitoneally injected with an equal amount of physiological saline 15 minutes before constructing LIRI model； rats in Control group were intraperitoneally injected with an equal amount of physiological saline 15 minutes before freeing left pulmonary hilum； rats in other groups were intraperitoneally injected with corresponding dose of drug 15 minutes before constructing LIRI model. The wet/dry weight ratio of lungs was calculated. HE staining was used to study lung tissue pathology. Immunofluorescence staining was used to detect the relative fluorescence intensity of gasdermin D （GSDMD） and NLRP3 double positive cells in lung tissue. ELISA was used to detect interleukin-1β and IL-18 in lung tissue. Western blot was used to detect HIF-1α， NLRP3， cysteine-aspartic protease-1 （Cleaved caspase-1）， and gasdermin D-N （GSDMD-N） proteins in lung tissue. ResultsCompared to the Control group， the LIRI group showed disordered alveolar structure， thickened alveolar septa， and abundant inflammatory cell infiltration in rats. The lung wet/dry weight ratio， relative fluorescence intensity of GSDMD and NLRP3 double positive cells in lung tissue， IL-1β， IL-18 levels， and HIF-1α， NLRP3， Cleaved caspase-1， and GSDMD-N proteins increased （P0.05）. For the LIRI group， rats in the RMZL low， medium， and high-dose groups displayed attenuated alveolar septal thickening and reduced inflammatory cell infiltration. The lung wet/dry weight ratio， relative fluorescence intensity of GSDMD and NLRP3 double positive cells in lung tissue， IL-1β， IL-18 levels， and HIF-1α， NLRP3， Cleaved caspase-1， and GSDMD-N proteins declined， and the RMZL high-dose group showed the most prominent trend （P0.05）. Compared with the RMZL high-dose group， rats in the RMZL high-dose+DMOG group exhibited thickened alveolar septa and more inflammatory cell infiltration， along with increased lung wet/dry weight ratio， relative fluorescence intensity of GSDMD and NLRP3 double positive cells in lung tissue， levels of IL-1β and IL-18， and protein expression of HIF-1α， NLRP3， Cleaved caspase-1， and GSDMD-N （P0.05）. ConclusionRMZL may inhibit pyroptosis in LIRI rats by suppressing HIF-1α/NLRP3 pathway.

【Objective】 To determine the optimal process conditions for efficiently extracting human prothrombin complex concentrates from human plasma. 【Methods】 Using human plasma as the materials and the yield of prothrombin complex concentrates as the evaluation standard, the preparation process parameters were studied and optimized through design of exporement(DOE), orthogonal experiments, and single factor experiments. 【Results】 The optimal process conditions were as follows: DEAE Sephadex A50 gel was selected, which balanced to pH 7.6, and then the amount of 1.7-2.5 g/L of plasma weight is added into the cryoprecipitate supernatant for adsorption for 40 minutes; Washing solution (0.15-0.175 mol/L sodium chloride) with 3 times the volume of gel was washed 3 times, and eluent (0.5-2.0 mol/L sodium chloride) was washed 3 to 5 times; Add stabilizer (heparin 35 IU, sodium chloride 0.1 mol/L) for ultrafiltration dialysis. 【Conclusion】 By using the optimized process mentioned above, the yield(measured by human coagulation factor IX)can reach 620 000 to 630 000 IU/ton of plasma, which is suitable for large-scale production.

To establish rat model of lung ischemia/reperfusion (IR) in vivo, and to explore the effects of acidification pretreatment for respiratory acidosis on the expression of matrix metalloproteinase-9 (MMP-9) and the possible mechanisms.
 Methods: A total of 36 male Sprague-Dawley rats were divided into a sham group (S group), a IR group, and an experiment group (RA group) (n=12 in each group). The rat left lung hilum in the S group was dissociated, followed by perfusion without ischemia. After the left lung hilum in the IR group was blocked for 45 min, the rats were followed by reperfusion for 180 min. After left lung hilum in the RA group was dissociated, the respiratory parameters were adjusted so that pressure of end tidal carbon dioxide (PETCO2) reached 56-65 mmHg (1 mmHg=0.133 kPa) for 5 min, then the rats was subjected to IR. Lung tissue wet/dry (W/D) and lung permeability index (LPI) were calculated, while the lung histopathology was observed and the MMP-9 protein expression were measured.
 Results: Compared with the control group, the W/D and LPI in the IR group and the RA group increased after reperfusion (both P<0.05), and the levels of W/D and LPI in the group RA were lower than that in the IR group (P<0.05). LPI and pathology scores were significantly lower in the RA group than those in the IR group (both P<0.01). After IR, the expression of MMP9 in the lung tissues in the IR group and the RA group increased significantly (both P<0.01). The expression of MMP-9 protein in the RA group was significantly lower than that in the IR group (P<0.01).
 Conclusion: After lung IR injury, the expression of MMP-9 protein, vascular permeability and inflammatory exudation is increased. The acidification pretreatment for respiratory acidosis can inhibit the expression of MMP-9 protein and reduce inflammatory exudation after lung IR, showing a protective effect on lung IR injury.
Acidosis, Respiratory ; drug therapy ; prevention & control ; Animals ; Gene Expression Regulation, Enzymologic ; drug effects ; Lung ; enzymology ; Lung Injury ; enzymology ; Male ; Matrix Metalloproteinase 9 ; genetics ; Rats ; Rats, Sprague-Dawley ; Reperfusion Injury ; drug therapy ; prevention & control

Objective To compare the treatment effect and study the efficacy of the elastic intramedullary nails for the treatment of primary aneurysmal bone cysts in limbs.Methods Twenty one children with primary aneurysmal bone cystsadmitted to and treated in Shanghai Children's Hospital from 2012 January to 2016 June were studied retrospectively.There were 18 males and 3 females,with overall age of 1-14 years old and median age of 5 years old.The lesions were mainly located in the femur,tibia,fibula and humerus.They were divided into 2 groups according to the treatment plan.The patients of the experimentgroup received curettage and bone grafts with high-speed burring and elastic intramedullary nail.The patients of the control group received curettage and bone grafts with high-speed burring.According to the imaging results (Neer grading) and MSTS functional evaluation,the curative effect of the children of the 2 groups were analyzed statistically.Results The cure children were followed up for more than 2 yearswith follow-up time range of 24-48 months (mean value of 32.29±8.22 months).Five patients had a recurrence,with mean postoperative recurrence time of 10±2.66 months.A total of 5 patients of the control group perceived curettage and bone grafts with high-speed burring and a total of 16 patients of the experimentgroup received curettage and bone grafts with high-speed burring andelastic intramedullary nail.According to the imaging results (Neer grading) and MSTS function evaluation,Neer grading was 3 cases for grade Ⅰ,0 case for grade Ⅱ,1 case for grade Ⅲ and 12 cases for grade Ⅳ in the experiment groups.That was 1 case for grade Ⅰ,1 case for grade Ⅱ,2 cases for grade Ⅲ and 1 case for grade Ⅳ in the control group.The ABC recurrence rate of experimental group (18.8％) was lower than matched group (40％),while there was no significant difference.We found that MSTS functional scores of experimental group was significantly higher than the matched group (28.88±2.22 vs 20.80± 10.38,t=3.058,P=0.006).According to postoperative MSTS functional evaluation,we found that even the patients in the study group with recurrencewere also able to participate in physical exercises,without further occurrence of pathological fracture and the postoperative life quality was greatly improved.Conclusion Curettage and bone grafts with high-speed burring andelastic intramedullary nail can significantly reduce the recurrence rate of primary aneurysmal bone cysts in the four limbs.Meanwhile the MSTS function evaluation of the recurrence cases in this group all achieve to a satisfactory level.The reason of recurrence may be correlated to patient age and the distance between the focus and epiphyseal plate.Therefore,an appropriate treatment protocol is helpful in reducing the relapse rate and improving the patients' postoperative living quality.