Objective To observe the effects of Levo-tetrahydropalmatine(l-THP)on the expression,regression and relapse of conditioned place preference(CPP)in ketamine induced rats,and to detect the content of dopamine(DA)in the striatum(caudate putamen,CPu)of the rat brain at different time points.Methods Ketamine addiction rat model was established by CPP.The effects of l-THP on the expression,regression and relapse of ketamine induced rat CPP were investigated using CPP score as the index.The content of DA in CPu of rats was determined by ultra-performance liquid chromatography coupled to tandem mass spectrometry(UPLC-MS/MS)after ketamine administration and l-THP intervention at 30 min,60 min,90 min,120 min and 150 min.Results It indicated that 1-THP could decrease the expression of CPP in ketamine induced rats,promote the process of CPP resolution and inhibit the process of relapse.In addition,l-THP combined with ketamine administration significantly inhibited the ketamine-induced increase in DA content in the CPu of the rats.Conclusion The mechanism of l-THP inhibiting the reward effect of ketamine may be related to blocking DA receptors and reducing the release of DA neurotransmitters.l-THP has potential implications for the treatment of ketamine addiction.

Objective To determine the effect of isopsoralen(ISO)on the healing of tibia fracture in mice and explore its underlying mechanism.Methods Fifty male C57BL/6 mice(2 month old,20±2 g)were randomly divided into model group and ISO treatment group,with 25 animals in each group.From the 3rd day after modeling,the mice from the ISO group were given an intragastric gavage of 40 mg/kg ISO,once per day for 28 consecutive days,while those of the model group was given same volume of normal saline in same way.On the 7th,14th,21st,and 28th day after gavage,the tibia on the surgical side was taken,and the fracture area was quantified by bone volume/total volume(BV/TV)after micro-CT scanning.The healing and shaping of the fracture end were observed through HE staining.ELISA was used to detect the serum contents of bone alkaline phosphatase(BALP)and procollagen type I N-terminal peptide(PINP)on the 14th day of gavage.Western blotting was employed to determine the expression levels of Collagen Ⅰ,Runx2,BMP2,OSX,and VEGF in the tibial callus tissue in 7 and 14 d after gavage.Vascular perfusion was applied to observe the callus microvessels in 28 d to quantitatively analyze the vascular volume fraction and vessel diameter.Immunohistochemical staining was conducted to observe the expression of VEGF in the callus in 14 d after gavage.Results HE staining displayed that the ISO group had faster healing process than the model group.Micro-CT quantification results showed that the ISO group had higher BV/TV ratio in 7 d after gavage though no statistical difference,significantly higher ratio in 14 d(P＜0.05),but obviously lower ratio in 21 and 28 d after gavage(both P＜0.05)when compared with the model group.The serum contents of BALP and PINP were also remarkably higher in the ISO group than the model group(P＜0.05).Western blotting results indicated that the expression levels of Collagen Ⅰ,Runx2,BMP2,OSX and VEGF in the ISO group were higher than those in the model group(P＜0.05).The results of angiography revealed that the vascular volume fraction and vessel diameter were notably increased in the ISO group than the model group(both P＜0.05).Immunohistochemical assay showed that the expression of VEGF was higher in the ISO group than the model group(P＜0.05).Conclusion ISO can improve the activity of osteoblasts,increase the expression of osteogenesis-related proteins,and accelerate the angiogenesis to promote fracture healing.

Objective:To investigate the effect of sinusoidal alternating electromagnetic field(SEMF)on fracture healing and its mechanism.Methods:Femoral fracture model was established using specific pathogen free male Wistar rats.Thirty rats were randomly divided into the control and SEMF groups with 15 rats in each group.The SEMF group was given 50 Hz 1.8 mT for 90 min every day,while the control group was not treated.X-ray examinations were performed every two weeks to determine the formation of bone scabs.Three rats from both groups were sacrificed after 2 and 4 weeks of treatment.Protein was extracted from the fractured femurs,and the expression of type Ⅰ collagen(COL-1),osterix(OSX),Runt-related transcription factor 2(RUNX2),and vascular endothelial growth factor(VEGF)was detected by Western blotting.After 8 weeks,the femur on the operated side was taken for micro-CT scanning to observe fracture healing,angiography to observe blood vessel growth,and organs such as hearts,livers,spleens,lungs,and kidneys were taken for safety evaluation by hematoxylin-eosin staining(HE staining).Results:The bone scab scores of the SEMF group were significantly higher than those of the control group after 2,4,6,and 8 weeks of treatment(all P<0.01).The fracture healing of the SEMF group was better than that of the control group after 8 weeks,and the bone volume scores of the two groups were 0.243±0.012 and 0.186±0.008,respectively(P<0.01);the number of blood vessels in the SEMF group was also more than that of the control group after 8 weeks.Western blotting results showed that the expressions of COL-1,OSX,RUNX2,and VEGF were higher in the SEMF group than those in the control group after 2 and 4 weeks of treatment(all P<0.05).HE staining showed that histopathological results of the examined organs were normal in both groups.Conclusion:SEMF can accelerate fracture healing by promoting the expression of osteogenic factors and vascular proliferation without significant adverse effects.

Objective    To evaluate the safety and efficacy of peripheral cannulation for cardiopulmonary bypass (CPB) in patients with reoperation of congenital heart disease. Methods    The perioperative data of patients with congenital heart disease who underwent reoperation in Fuwai Hospital from 2019 to 2020 were retrospectively collected. They were divided into two groups according to the cannulation methods: a central group and a peripheral group. The prognosis of the patients was analyzed. Results     A total of 80 patients were collected, including 43 patients in the central group, and 37 pateints in the peripheral group. In the central group, the median age was 18 (14, 32) years, and 21 patients were male. The median age of the peripheral group was 16 (10, 27 ) years, and 18 patients were male. The CPB time in the peripheral group was 201 (164, 230) min, which was longer than that in the central group [143 (97, 188 ) min, P<0.001]. The lactate after CPB in the peripheral group was statistically higher than that in the central group [2 (1, 2 ) mmol/L vs. 1 (1, 1) mmol/L, P=0.002]. The dosage of albumin use during CPB in the peripheral group was statistically higher than that in the central group [10 (0, 20) g vs. 0 (0, 0) g, P=0.004]. There was no statistical difference in the postoperative dosage of red blood cells use [0 (0, 2) U vs. 0 (0, 0) U, P=0.117], mechanical ventilation time [14 (11, 19) h vs. 13 (10, 15) h, P=0.296], ICU stay time [43 (23, 80) h vs. 40 (20, 67) h, P=0.237] or postoperative hospital stay time [10 (7, 12) d vs. 8 (7, 10) d, P=778] between the two groups. Conclusion    It’s safe and efficient to establish CPB through peripheral cannulation in patients with complex congenital heart disease undergoing reoperation.

Objective:To study the effects of a simulated plateau environment on fracture healing in rats.Methods:A rat model of mid-femoral fracture was established by hacksaw truncation and intramedullary fixation with Kirschner wires in 60 male Wistar rats which were divide into 2 groups ( n=30) by the random number table method. The rats in the control group were raised in the animal experiment center of The 940 Hospital of Joint Logistic Support Force of Chinese PLA at an altitude of 1,400 m, while the rats in the plateau group were placed in an animal experimental cabin in a simulated plateau environment at a simulated altitude of 5,000 m. The body weight was weighed once a week and X-ray films were taken every 2 weeks. Blood samples were collected after 4 weeks for detection of biochemical indicators of bone metabolism. After 8 weeks, the femurs of the surgical side were taken for bone biomechanical detection and the bone mineral density of the healthy side was detected. After 4 and 8 weeks, the femurs of the surgical side were taken for in vitro Micro-CT scanning and angiography detection. After 1, 2, 4 and 8 weeks, the femurs of the surgical side were taken for bone histopathologic detection. Results:During the entire experiment, no rats in the control group died while the mortality rate of the rats in the plateau group was as high as 26.7% (8/30). In the plateau group, some organs were pathologically damaged in the rats, fracture union was delayed, and the callus differentiated and matured slowly with the chondrocytes still dominant at the 8th week. The bone mineral density and the maximum load of the femur in the plateau group were significantly lower than those in the control group ( P< 0.05). Angiography showed that the rats in the plateau group had microvascular proliferation which did not penetrate the fracture end at the 8th week. The bone formation indexes like osteocalcin, procollagen type Ⅰ N-terminal propeptide (PⅠNP), and osteoprotegerin of the rats in the plateau group were significantly lower than those in the control group at the 4th week ( P<0.05). The bone resorption indexes like tartrate resistant acid phosphatase 5b (TRACP-5b) and receptor activator for nuclear factor-κB ligand (RANKL) in the plateau group were significantly higher than those in the control group ( P<0.05). Conclusion:A simulated plateau environment at an altitude of 5,000 m may lead to delayed fracture healing in rats.

Objective To construct SLC6A4-shRNA lentiviral vector, establish PC12 cells stable transformation cell line，and detect the effect of SLC6A4 gene silencing on hypoxia induced PC12 cells apoptosis. Methods Three specific targets sequence of SLC6A4 were designed and short hairpin RNA was synthesized, and then were recombined into shRNA expression vector GV248 plasmid, with non-homology shRNA sequence as negative control. The connection products were switched to competent cells. After dentification and sequencing, the vectors were co-transfected with the auxiliary vectors into 293T cells in order to produce recombinant shRNA lentiviral particles. Then, PC12 cells were infected with the recombinant lentiviral and screened by puromycin. The PC12 cells were divided into two groups: lentiviral negative control group (NC-shRNA) and SLC6A4-silenced group (SLC6A4-shRNA). The expression of SLC6A4 mRNA was detected by real-time fluorescence quantitative and the 5-HTT protein level was assayed by Western blot, The effect of SLC6A4 gene silencing on hypoxia induced apoptosis was detected by flow cytometry. Results The SLC6A4-shRNA lentiviral expression vector was constructed and the recombinant lentiviral particles by packaging the 293T cells were obtained, the stably infected PC12 cells were established after filtering. Compared with negative control group, the expression level of SLC6A4 gene and 5-HTT protein in SLC6A4-shRNA group was suppressed notably (P<0.01). It was confirmed that lentiviral vector could effectively silence SLC6A4 gene in PC12 cells and SLC6A4 gene silencing could decrease apoptosis rate of PC12 cells under hypoxia condition. Conclusion The SLC6A4 gene of PC12 cells could be effectively silenced by shRNA lentivirus vector，which could reverse hypoxia induced apoptosis.

Objective To study the possible mechanism of 7-hydroxyethyl chrysin (7-HEC) on high altitude cerebral edema (HACE). Methods A rat model of high altitude cerebral edema was established. The activity of superoxide dismutase (SOD) and the content of malondialdehyde (MDA) in rat brain tissues were measured. The expression levels of apoptosis, cell cycle and autophagy related proteins were detected by Western blotting to explore the protective effect of 7-HEC on high altitude cerebral edema and its mechanism. Results Compared with the control group, the content of MDA in the brain tissue of the hypoxia model group was significantly up-regulated; the activity of SOD was significantly down-regulated, the relative expression of CyclinD1, CyclinE1, CDK6 and CDK2, apoptotic proteins Bcl-2, PARP, and autophagy protein LC3-B were down-regulated; and the relative expression of apoptotic protein Bax and autophagy protein P62 were up-regulated; the difference was statistically significant (P<0.05); Compared with the hypoxia model group, the content of MDA was down-regulated and the activity of SOD was significantly up-regulated in the 7-HEC administration group. The relative expression of CyclinD1, CyclinE1, CDK6, CDK2, apoptotic proteins Bcl-2, PARP, autophagy protein LC3-B was up-regulated and the relative expression of apoptotic proteins Bax and the relative expression of autophagy protein P62 was down-regulated in the 7-HEC administration group. The difference was statistically significant (P<0.05). Conclusion 7-HEC has a certain protective effect on high altitude cerebral edema, and its mechanism may be related to the regulation of cell cycle, autophagy, apoptosis and oxidative stress pathways.

Objective: To evaluate the predictive value of 3 different risk stratification models including the risk adjustment in congenital heart surgery-1 (RACHS-1), Aristotle basic complexity (ABC), and Society of Thoracic Surgeons-European Association for cardiothoracic surgery congenital heart surgery mortality score (STAT) risk scoring system for death and major complications in patients after congenital heart surgeries. Methods: A total of 3 578 patients (age<18 years old) received surgery for congenital heart diseases from January to December 2015 in Fuwai hospital were enrolled, and the clinical data were retrospectively analyzed. The congenital heart disease patients were 1.7 (0.8, 4.5) years old, and the male accounted for 54.3% (1 943 cases).Death after surgery and major complications including use of extracorporeal membrane oxygenation, bedside thoracotomy, peritoneal dialysis for renal failure, bedside hemofiltration for renal failure, tracheotomy, reoperation for mediastinum infection, reoperation for heart in hospital were observed. The area under the receiver operating characteristic (ROC) curve was calculated to evaluate the predictive value for mortality after surgery and major complications with RACHS-1, ABC, and STAT risk scoring systems. Results: The mortality after surgery was 0.4% (14/3 578) , and the rate of major complications was 3.2% (113/3 578) . For mortality after surgery, areas under the ROC curve were 0.682 (95%CI 0.570-0.795, P=0.002), 0.722 (95%CI 0.612-0.832, P<0.001), and 0.753 (95%CI 0.659-0.847, P<0.001) with RACHS-1, ABC and STAT risk scoring systems, respectively. For major complications, areas under the ROC curve were 0.709 (95%CI 0.667-0.751, P<0.001), 0.743 (95%CI 0.702-0.784, P<0.001), and 0.731 (95%CI 0.693-0.770, P<0.001) with RACHS-1, ABC and STAT risk scoring systems, respectively. Conclusion STAT risk scoring system is superior to RACHS-1 and ABC risk scoring systems on predicting death after surgery, and ABC risk scoring system is superior to RACHS-1 and STAT risk scoring systems on predicting major complications in Chinese patients with congenital heart disease in the single center.

Objective: To investigate the signal transduction mechanisms of time-dependent effects of 50 Hz 1.8 mT sinusoidal electromagnetic fields(SEMFs)on osteoblastic activity. Methods: Newborn rat calvarial osteoblasts(ROBs)were treated with 50 Hz 1.8mT SEMFs for 30, 60, 90, 120, and 150 min, respectively.Intracellular alkaline phosphatase(ALP)activity was assayed, and protein expression of Runt-related transcription factor 2(Runx2), Smad1/5/8 and mitogen-activated protein kinases(MAPKs)were examined by Western blot.The Dual-Luciferase Reporter Assay System was used to measure the activity of the Wnt pathway.Immunofluorescence staining and laser confocal microscopy were applied to examine the nuclear translocation of Smad1/5/8 and β-catenin.Changes in ALP activity were determined after inhibiting p38 MAPK using a specific inhibitor. Results: ALP activity of ROBs increased after 30, 60, 90, 120 and 150 min of SEMFs treatment, compared with the control group(51.41±5.21, 59.47±4.02, 67.56±4.68, 63.69±3.92, and 58.16±3.61 vs.45.53±3.24), and reached the highest value at 90 min and then started to decline.Protein expression of Runx-2, p-Smad1/5/8, p-p38 and β-catenin increased after SEMFs treatment, and reached the highest value at 90 min and then gradually returned to baseline levels.The values for Wnt pathway activity for the control group and with SEMFs treatment at 30, 60, 90, 120 and 150 min were 0.49±0.06, 0.52±0.09, 0.75±0.05, 0.77±0.42, 0.58±0.08 and 0.42±0.09, respectively.Wnt pathway activity, the nuclear translocation of β-catenin and Smad1/5/8 reached the highest level at 90 min.Values of ALP activity in the control group and the SEMFs group were 44.60±3.84 and 71.54±7.34, respectively, before specifically inhibiting p38 MAPK, and were 52.08±0.83 and 52.15±10.77, respectively, after p38 MAPK inhibition, indicating that ALP activity could not be increased with inhibition. Conclusions 50 Hz 1.8 mT SEMFs increase osteoblastic activity by activating the BMP-2/Smad1/5/8, Wnt/β-catenin and p38 MAPK signal pathways.The optimal duration of treatment is 90 min per day.