BACKGROUND:Ca2+expression in astrocytes has been found to be closely related to cognitive function,and the Ca2+signaling pathway regulated by inositol 1,4,5-trisphosphate receptors(IP3R2)and ryanodine receptor(RYR)2 receptors has become a hot spot in the study of cognitive disorder-related diseases. OBJECTIVE:To investigate the expression of Ca2+signals mediated by IP3R2 and RYR2 in hippocampal astrocytes in animal models of delayed encephalopathy after acute carbon monoxide poisoning,and to explore the possible pathogenesis of delayed encephalopathy after acute carbon monoxide poisoning. METHODS:C57BL mice with qualified cognitive function were selected by Morris water maze experiment and randomly divided into control group and experimental group.An animal model of delayed encephalopathy after acute carbon monoxide poisoning was established by static carbon monoxide inhalation in the experimental group,and the same amount of air was inhaled in the control group.Behavioral and neuronal changes,astrocyte specific marker glial fibrillary acidic protein,IP3R2,RYR2 receptor and Ca2+concentration in astrocytes of the two groups were detected using Morris water maze,hematoxylin-eosin staining,western blot,immunofluorescence double labeling and Ca2+fluorescence probe at 21 days after modeling. RESULTS AND CONCLUSION:In the Morris water maze,the escape latency of the experimental group was significantly longer than that of the control group(P<0.05).Hematoxylin-eosin staining results showed that in the experimental group,the number of hippocampal pyramidal cells decreased,the cell structure was disordered,and the nucleus was broken and dissolved.Immunofluorescence results showed that IP3R2 and RYR2 were co-expressed with glial fibrillary acidic protein in the hippocampus,and the expressions of IP3R2,RYR2 and glial fibrillary acidic protein were up-regulated in the hippocampus of the experimental group(P<0.05).Western blot analysis showed that the expressions of IP3R2,RYR2,and glial fibrillary acidic protein in the hippocampus of the experimental group were increased(P<0.05).Ca2+concentration in hippocampal astrocytes increased significantly in the experimental group(P<0.05).To conclude,astrocytes may affect Ca2+signals by mediating IP3R2 and RYR2 receptors,then impair the cognitive function of mice with carbon monoxide poisoning,and eventually lead to delayed encephalopathy after acute carbon monoxide poisoning.

Hepatic encephalopathy （HE） is a common complication of severe liver disease in the end stage， and it is urgently needed to improve the rate of effective treatment and clarify the pathogenesis of HE. The liver is a crucial hub for immune regulation， and disruption of immune homeostasis is a key factor in the pathological mechanisms of HE. As the main metabolites of intestinal flora， short-chain fatty acids （SCFAs） play a vital role in the biological processes of both innate and adaptive immunity and can regulate the proliferation and differentiation of immune cells maintain the homeostasis of intestinal microenvironment and the integrity of barrier function. Studies have shown that SCFAs participate in bidirectional and dynamic interactions with the liver-gut-brain axis through immunomodulatory pathways， thereby playing an important role in the diagnosis， treatment， and prognostic evaluation of HE. Starting from the immunoregulatory effect of SCFAs， this article summarizes and analyzes the crosstalk relationship between SCFAs and the liver-gut-brain axis and the significance of SCFAs in the diagnosis and treatment of HE， in order to provide new ideas for optimizing clinical prevention and treatment strategies.

Nuclear factor-kappa B （NF-κB） is an important intracellular transcription factor widely involved in the processes such as immune response， inflammatory response， cell proliferation， and apoptosis. The abnormal activation of the NF-κB signaling pathway plays a pivotal role in various liver diseases including chronic hepatitis， liver fibrosis， liver cirrhosis， and hepatocellular carcinoma. Extensive studies have shown that inhibiting NF-κB activity may effectively reduce inflammation and fibrosis and improve metabolic disorders. Several natural compounds， such as matrine and salvianolic acid B， have shown the potential in suppressing NF-κB activity， thereby exerting anti-inflammatory， anti-fibrotic， and anti-tumor effects. This article systematically reviews the critical role of the NF-κB signaling pathway in liver diseases and its potential as a therapeutic target， in order to highlight its potential as a therapeutic target for liver diseases and provide new directions for the treatment of liver diseases.

Objective:To investigate the effects and mechanism of exosome (EXO)-loaded kringle V11 (KV11) delivery on corneal neovascularization (CNV).Methods:KV11 was bound to the surface of endothelial cell-derived exosomes by using CP05, an EXO-targeting anchoring peptide, to produce EXO-KV11.The binding efficiency and optimal concentration ratio were determined using the Apogee flow system.A total of 100 8-week-old healthy male SPF grade SD rats were selected, 10 of which were randomly selected as a normal control group without any treatment.The CNV model was established by alkali burn in the other 90 rats, which were randomly divided into three groups, EXO-KV11 group, KV11 group, and normal saline group by the random number table method, with 30 rats in each group.Each group was injected subconjunctivally with 100 μl of EXO-KV11 (25 μg), KV11 (25 μg), or normal saline every other day from the first day after the alkali burn, respectively.The CNV of rats was observed on days 1, 4, 7, and 14 after alkali burn.The CNV area was calculated by ventricular perfusion with fluorescein isothiocyanate-dextran (FITC-dextran) and corneal angiography.The amount of CNV lumen was observed by hematoxylin and eosin staining.The distribution of CD31 in rat corneas was determined by immunohistochemical method.The expression levels of voltage-dependent anion channel 1(VDAC1), endoplasmic reticulum stress, autophagy and apoptosis-associated proteins were detected by Western blot.This study was approved by the Animal Ethics Committee of Peking University People's Hospital (No.20210019). All animal procedures complied with the regulations of the Vision and Ophthalmology Association and the Animal Protection and Use Committee of Peking University.Results:The optimal concentration ratio of KV11 to EXO was 4∶1 and the binding affinity reached up to 87.5% by Apogee flow cytometers.On days 7 and 14 after alkali burn, there were significant differences in CNV area among the four groups ( F=4.613, 15.590; both at P<0.05). On day 7 after alkali burn, the CNV area was smaller in EXO-KV11 group than in KV11 and normal saline groups, with statistically significant differences (both at P<0.05). On day 14 after alkali burn, the CNV area was smaller in EXO-KV11 and KV11 groups than in normal saline group, and smaller in EXO-KV11 group than in KV11 group, showing statistically significant differences (all at P<0.05). The results of quantitative analysis of corneal fluorescence mounts showed that the relative CNV fluorescence area of the normal saline group, KV11 group and EXO-KV11 group were (8.3±1.7)%, (5.2±1.6)%and (3.4±0.7)%, respectively, showing a statistically significant overall comparison difference ( F=11.735, P<0.01). The relative CNV fluorescence area was larger in KV11 and normal saline groups than in EXO-KV11 group, and larger in normal saline group than in KV11 group, showing statistically significant differences (all at P<0.05). On day 14 after alkali burn, massive neovascular lumens were observed in the matrix of the normal saline group.The number of neovascular lumens in KV11 group was smaller than that in normal saline group.The corneal structure appeared normal in EXO-KV11 group, and neovascular lumens were rare.Numerous CD31-positive cells were observed in the corneal stroma of the normal saline group, which formed into lumen structures.The number of lumens surrounded by CD31-positive cells in the corneal stroma was smaller in KV11 group than in normal saline group, and smaller in EXO-KV11 group than in KV11 group.There were significant differences in the relative expression levels of VDAC1, protein kinase R-like endoplasmic reticulum kinase (PERK), p62, cleaved caspase 3 among the four groups ( F=35.960, 8.947, 17.791, 101.168; all at P<0.01). The relative expression levels of VDAC1, PERK, p62, cleaved caspase 3 were higher in EXO-KV11 group than in KV11 and normal saline groups, showing statistically significant differences (all at P<0.001). There was no significant difference in the relative expression of microtubule-associated proteins 1A/1B light chain 3B (LC3B)Ⅱ/LC3BⅠ protein among all four groups ( F=0.445, P=0.727). Conclusions:EXO-KV11 can inhibit CNV more remarkably than KV11.EXO-KV11 inhibits CNV by promoting the expression of VDAC1 and PERK and suppressing the autophagic flux.

With intensified aging， Alzheimer's disease has become a serious problem in China's health field. In the field of traditional Chinese medicine （TCM）， Alzheimer's disease mainly describes cognitive deficits such as dementia and amnesia. After the inheritance and summary by medical experts of successive generations， the theory of "toxin damaging brain collaterals" has become a mature pathogenesis hypothesis of this disease. Blood stasis， as one of the main viral pathogens， is also closely related to the theory of Alzheimer's disease in modern pharmacology. Chuanxiong Rhizoma is used frequently in clinical prescriptions for Alzheimer's disease. As the main component of Chuanxiong Rhizoma， tetramethylpyrazine has a series of pharmacological effects on the cardiovascular system such as vasodilation， anti-platelet aggregation， anti-atherosclerosis， and anti-myocardial ischemia， which reflects the effects of Chuanxiong Rhizoma in activating blood circulation and removing blood stasis. However， few studies have focused on the effect of tetramethylpyrazine on the pathogenesis of Alzheimer's disease. From the perspective of TCM theory and modern pharmacology， this article discussed the effects of tetramethylpyrazine on the pathology and pathogenesis of Alzheimer's disease from the aspects of cardiovascular function， oxidative stress， inflammatory response， mitochondrial function， and cholinergic system and made prospects for the future application of tetramethylpyrazine to prevent and treat Alzheimer's disease.

Objective To investigate the value of polar residual network(PResNet)model for assisting evaluation on rat myocardial infarction(MI)segment in myocardial contrast echocardiography(MCE).Methods Twenty-five male SD rats were randomly divided into MI group(n=15)and sham operation group(n=10).MI models were established in MI group through ligation of the left anterior descending coronary artery using atraumatic suture,while no intervention was given to those in sham operation group after thoracotomy.MCE images of both basal and papillary muscle levels on the short axis section of left ventricles were acquired after 1 week,which were assessed independently by 2 junior and 2 senior ultrasound physicians.The evaluating efficacy of MI segment,the mean interpretation time and the consistency were compared whether under the assistance of PResNet model or not.Results No significant difference of efficacy of evaluation on MI segment was found for senior physicians with or without assistance of PResNet model(both P＞0.05).Under the assistance of PResNet model,the efficacy of junior physicians for diagnosing MI segment was significantly improved compared with that without the assistance of PResNet model(both P＜0.01),and was comparable to that of senior physicians.Under the assistance of PResNet model,the mean interpretation time of each physician was significantly shorter than that without assistance(all P＜0.001),and the consistency between junior physicians and among junior and senior physicians were both moderate(Kappa=0.692,0.542),which became better under the assistance(Kappa=0.763,0.749).Conclusion PResNet could improve the efficacy of junior physicians for evaluation on rat MI segment in MCE images,shorten interpretation time with different aptitudes,also improve the consistency to some extent.

Objective:To evaluate the feasibility of a new ultrasonic parameter to assess right ventricular-pulmonary artery (RV-PA) coupling in patients with acute pulmonary embolism (APE).Methods:A retrospective analysis was performed in 140 patients with APE diagnosed by computed tomography pulmonary angiography (CTPA) in the Second Affiliated Hospital of Harbin Medical University from August 2017 to June 2020. According to the tricuspid annular plane systolic excursion/pulmonary arterial systolic pressure (TAPSE/PASP) ratio cutoff value 0.40 mm/mmHg reported by the European Society of Cardiology in 2020, the patients were divided into the coupling group ( n=99) and the uncoupling group ( n=41). The conventional ultrasonic parameters of the 2 groups were measured, and then several ultrasonic parameter ratios were obtained. The new ultrasonic parameter, which can replace the TAPSE/PASP ratio, was screened out by Spearman correlation analysis, and ROC curve was plotted to calculate the diagnostic efficacy of this parameter. Results:①Compared with the coupling group, patients in the uncoupling group were older and more likely to be accompanied by dyspnea and venous thrombosis in the lower extremities (all P<0.05), but there was no significant difference in other general data(all P>0.05); ②Compared with the coupling group, tricuspid regurgitation velocity (TRV), tricuspid regurgitation pressure gradient(TRPG), PASP, right ventricle end-diastolic transverse diameter(RVTD), inferior vena cava(IVC) diameter and the ratio of early diastolic tricuspid inflow to tricuspid lateral annular velocity(E/e′), in the uncoupling group increased significantly (all P<0.05), and TAPSE, peak systolic velocity of tricuspid annulus(s′), TAPSE/PASP ratio, TAPSE/TRPG ratio, TAPSE/RVTD ratio and s′/TRPG ratio decreased significantly (all P<0.05); ③The TAPSE/TRPG ratio was highly correlated with TAPSE/PASP ratio ( rs=0.970, P<0.001); The TAPSE/TRPG ratio was still highly correlated with TAPSE/PASP ratio in the uncoupling and coupling groups ( rs=0.966, 0.922; all P<0.001). ④ROC analysis showed that the area under curve for TAPSE/TRPG in diagnosing RV-PA coupling was 0.992. At the cutoff of TAPSE/TRPG <0.625 mm/mmHg for indicating RV-PA coupling, the sensitivity and specificity were 97.6% and 92.9%, respectively. Conclusions:TAPSE/TRPG ratio can be used as a new ultrasonic parameter to reflect RV-PA coupling, which is helpful for clinical identification of APE patients with high risk and poor prognosis.

Objective To conduct dynamic impact failure test of rabbit single vertebra, and make comparison with the static compression experiment, so as to study damage mechanism of the vertebral body under the axial impact. Methods The voltage waveform diagram of the force sensor and the detailed process of the vertebral impact were obtained by the oscilloscope and high-speed photography through the drop hammer dynamic impact experimental device. Results The average static load of the thoracic and lumbar vertebra were 910 N and 947 N, respectively; the average dynamic load of the thoracic and lumbar vertebra were 1 196 N and 1 026 N, respectively; the average thoracic and lumbar dynamic load coefficients were 1.37 and 1.08; under static load, the average stress of the thoracic and lumbar vertebra was 15.28 MPa and 12.51 MPa, respectively; under dynamic load, the average stress of the thoracic and lumbar vertebra was 20.03 MPa and 13.56 MPa; during dynamic impact, the mean longitudinal strain and transverse strain was -0.3 and -0.005 (compression); under dynamic conditions, the destruction energy of vertebrae increased from 0 J to 4.4 J. Conclusions Under dynamic and static experimental conditions, the dynamic load of the same vertebral body was greater than that of the static load; the average dynamic load coefficient of the thoracic vertebra was larger than that of the lumbar vertebra; the equivalent stress of the thoracic vertebra was greater than that of the lumbar vertebra; the axial strain of vertebra under impact was greater than the transverse strain; energy growth of the vertebral body presented a slow at first and then a rapid changing process. The research findings can provide some guidance for prevention and rehabilitation of human vertebral body injury in clinic.

OBJECTIVE：To analyze the occurrence of acute kidney injury （AKI）after lung transplantation and its possible influential factors . METHODS ：Medical records of 64 patients who received lung transplantation in our hospital from April 2017 to June 2018 were included in this retrospective study. Patients were divided into AKI group （44 cases）and non-AKI group （20 cases），according to whether AKI occurred after operation. According to diagnostic criteria for lung transplantation in our hospital ， all patients were given Methylprednisolone sodium succinate for injection or Methylprednisolone sodium succinate for injection combined with Basiliximab for injection ，and triple immunosuppressive therapy of Tacrolimus capsules+Mycophenolate mofetil dispersible tablets or Mycophenolate mofetil capsules or Mycophenolate sodium enteric-coated tablets+Methylprednisolone tablets or Prednisone acetate tablets were given after operation. The occurrence of AKI in AKI group within a week after operation were recorded. Intraoperative influential factors （operation type ， operation duration ， ECMO support ， immune inhibitor use ， intraoperative blood loss ），postoperative influential factors [days of ICU ，mechanical ventilation and ECMO support ，median value of Scr within one week after operation ，median tacrolimus concentration and the use of potential nephrotoxic drugs （≥4 kinds）， hospitalization days] and survival rate one year after operation were observed in 2 groups. RESULTS ：Within one week after lung transplantation，44 patients（68.8％）had experienced at least one episode of AKI ，among which 19 cases（29.7％）were stage 1， 17 cases（26.5％）were stage 2 and 8 cases（12.5％）were stage 3. The incidence of AKI was the highest on post-operative day 4 （57.4％）. The incidence of AKI at stage 3 exhibited growth trend within the first week after operation ，and reached the highest on median post-operative day 5（8.7％）. Operation duration ，median value of Scr within one week after operation ，median tacrolimus concentration in non-AKI group were significantly shorter or lower than AKI group ；there was no significant difference in operation type， ECMO support ， use of immunosuppressive agents ， intraoperative blood loss ，ICU days ，mechanical ventilation days，ECMO support days ，the utilization rate of potential nephrotoxic drugs （ ≥4 kinds） and hospitalization days between 2 groups （P＞0.05）. There was no statistical significance in the survival rate at stage 1 and 2 one year after operation between AKI group and non-AKI group （P＞0.05）. One year after operation ，survival rate of AKI group at stage 3 was significantly lower than that of non-AKI group （P＜0.05）. CONCLUSIONS：The incidence of AKI is high after lung transplantation. Operation duration ，median value of Scr within one week after operation ，median tacrolimus concentration were possible factors for the occurrence of AKI after operation.

OBJECTIVE： To study the correlation of tacrolimus concentrations among transplant patients’ whole blood， plasma and blood cells， analyze the effects of transplant types and ages on the their correlation， and to provide reference for rational drug use in clinic. METHODS： Totally 20 patients receiving tacrolimus anti-rejection therapy after transplantation and undergoing therapeutic drug monitoring （TDM） were randomly selected. According to the type of transplantation， they were divided into renal transplantation group and lung transplantation group （10 cases for each group）.  According to age， they were divided into three groups： 20-40 years old group， 41-60 years old group and 61-80 years old group （4， 9， 7 cases for each group）. Their residual blood after TDM was collected. Chemiluminescence microparticle immuno assay  （CMIA） was used to detect the concentration of tacrolimus in whole blood. UPLC-MS/MS was used to measure the concentrations of tacrolimus in plasma and blood cells. Pairs plots and Spearman rank correlation analysis were used to analyze the correlation of tacrolimus between whole blood and plasma， between whole blood and blood cells， between plasma and blood cells as well as the effects of transplant types and ages on tacrolimus concentrations among tansplant patient’s whole blood， plasma and blood cells. RESULTS： The correlation of tacrolimus concentrations in whole blood and plasma （r＝0.623，P＜0.01） was slightly stronger than that of whole blood and blood cells （r＝0.591， P＜0.01）； while  the correlation of tacrolimus concentration in plasma and blood cells was relatively weak （r＝0.497，P＜0.05）. Transplant type and age had an effect on the correlation of tacrolimus concentrations among patients’ whole blood， plasma， blood cells. The correlation of tacrolimus concen- tration in whole blood， blood cells and plasma in renal transplantation group was also weak （all r＜0.5）， and was weaker than that in lung transplantation group. The correlation of tacrolimus concentration among whole blood， plasma and blood cells was weak in patients of aged 20-40 years old group （all r＜0.3）， and was weaker than that of patients of aged 41-60 years old group and 61-80 years old group. CONCLUSION： Post-transplantation patients’ tacrolimus concentrations in whole blood， plasma and blood cell have a weak correlation. Rejections and adverse effects should be monitored in these patients， especially those renal transplantation patients or those patients aged 20 to 40.