Objective To observe the effects of EPO on GDNF secretion and cell cycle of Schwann cells(SCs) in vitro,and explore how EPO improve peripheral nerve regeneration. Methods Devided the purified Schwann cells of primary culture into three groups:group A with DMEM culture solution contained 10%fetal bovine serum and without EPO,group B with DMEM culture solution as above and 10 U/ml EPO,group C with DMEM culture solution as above and 50 U/ml EPO.The GDNF level of each group was detected in the culture by ELISA,and carried out the flow cytometry of Schwann cells on each group.Results GDNF in culture solution of group B,group C was more than that of group A,and the S-stage rate(S%)and (S+G_2M)%of Schwann cells in group B and group C more than that of group A. Conclusion EPO can increase the GDNF secretion and enhance proliferation activity of Schwann cells,which can explain how EPO improve peripheral nerve regeneration.

Objective To investigate the biological characteristics of human umbilical cord derived mesenchymal stem cells(UCMSCs) and inducing them to differentiate into neurons in vitro,in order to provide stem cell resource for the tissue engineering artificial nerve. Methods UCMSCs were cultured from Wharton jelly of human umbilical cord in the condition of sterilitas,surface antigens of UCMSCs were detected by immunohistochemistry.The frist group of cells were added by virgin nutrient,the second group of cells were induced by merely growth factors,the third of cells were induced by merely astragalus mongholicus and the fourth by the astragalus mongholicus with growth factor,observed the morphology of the cells of the two groups under inverted microscope,and determine the positive expression rate of nerve cells' markers,such as NSE,NF and GFAP.The results were statistically analyzed.Results UCMSCs were strongly positive for CD29,CD44,CD105,weakly positive for CD105 and negative for CD34,CD45.After induced by Astragalus mongholicus,UCMSCs were strongly positive for GFAP,NSE. Conclusion UCMSCs can be successfully cultured from the adherent tissue pieces,Astragalus mongholicus can successfully induce them to differentiate into neurons in vitro,to provide a new method of making the tissue engineering artificial nerve and treat theperipheraly nervus defect.

Objective:To compare the clinical efficacy of robot-assisted percutaneous screw implantation and free-hand open screw implantation by Wiltse approach in the treatment of thoracolumbar fracture.Methods:A retrospective cohort study was performed to analyze the clinical data of 71 patients with thoracolumbar fracture admitted to Second Affiliated Hospital of Soochow University from May 2018 to May 2020. There were 52 males and 19 females, with age range of 22-54 years［(41.0±7.8)years］. Of all, 33 patients were treated with robot-assisted percutaneous screw implantation (Group A) and 38 patients were treated with free-hand open screw implantation by Wiltse approach (Group B). Following parameters were measured, including frequency of radiation exposure, operation time, intraoperative blood loss, length of hospital stay, incidence of complications, rate of fracture healing at 3 months and 6 months postoperatively, visual analogue scale (VAS) and Oswestry dysfunction index (ODI) at 3 days, 3 months, 6 months postoperatively and at the last follow-up, anterior vertebral body height ratio and sagittal Cobb angle preoperatively, at 3 days postoperatively and at the last follow-up, and rate of screw implantation of grade A and B and rate of facet joint violation at 3 days postoperatively.Results:All patients were followed up for 10-24 months［(15.2±4.4)months］. Frequency of radiation exposure and operation time showed no statistical differences between the two groups (both P>0.05). Intraoperative blood loss was 100(100, 135)ml in Group A, less than 160(120, 200)ml in Group B ( P<0.01). Length of hospital stay was 8(7, 11) days in Group A, shorter than 12(10, 16)days in Group B ( P<0.01). There were no complications such as infection, spinal nerve injury or cerebrospinal fluid leakage in both group. There were no significant differences between the two groups in the rate of fracture healing at 3 and 6 months postoperatively (all P>0.05). VAS and ODI in Group A was 3(2, 4)points and 21(18, 23)points at 3 days postoperatively, lower than 4 (3, 5)points and 27(20, 32)points in Group B ( P<0.05 or 0.01), and the two groups showed no significant differences in VAS and ODI at other time points (all P>0.05). There were no significant difference in the anterior vertebral body height ratio or sagittal Cobb angle between the two groups at 3 days postoperatively and at the last follow-up (all P>0.05). Rate of screw implantation of grade A and B was 96.5% (191/198) in Group A, higher than 90.4% (206/228) in Group B ( P<0.05). Rate of facet joint violation was 4.0%(8/198) in Group A, lower than 11.8% (27/228) in Group B ( P<0.01). Conclusion:For thoracolumbar fracture, robot-assisted percutaneous screw implantation is superior to free-hand open screw implantation by Wiltse approach in terms of less bleeding, shorter hospitalization, earlier pain alleviation, higher accuracy of screw implantation and lower risk of facet joint violation.

This study was designed to compare the antithrombotic effects of salvianolic acid A and aspirin. The anti-platelet aggregation and anticoagulant effects of salvianolic acid A and aspirin in vitro and in vivo were investigated in normal rats. The anti-cerebral ischemia and anti-platelet aggregation effects of salvianolic acid A and aspirin were also investigated in rats with thrombotic cerebral ischemia. All animal care and experimental procedures were reviewed and approved by the Animal Ethics Committee of Chinese Academy of Medical Sciences. The results of antiplatelet aggregation in vitro and in vivo showed that salvianolic acid A could mildly inhibit adenosine diphosphate (ADP), arachidonic acid (AA) and thrombin (THR)-induced antiplatelet aggregation in a dose-dependent manner, while aspirin played a strong inhibitory effect on AA-induced platelet aggregation in vivo. The effects of salvianolic acid A and aspirin on the coagulation system were similar. At the same time, the results of maximum platelet aggregation rate (MAR) in the rat cerebral ischemia model [MAR_ADP= (41.67±4.55)%, MAR_AA= (53.22±2.83)%, MAR_THR= (73.33±5.04)%] indicated that salvianolic acid A could mildly inhibit ADP and AA-induced antiplatelet aggregation [MAR_ADP= (26.13±4.60)%, MAR_AA= (35.53±13.73)%, P<0.01], while aspirin played a strong inhibitory effect on AA-induced platelet aggregation [MAR_AA= (8.13±2.99)%]. Salvianolic acid A (10 mg·kg^-1) significantly improved the neurological function, cerebral infarction volume [(10.77±7.80)%] and brain edema [(79.72±0.83)%] compared with the model group [(43.50±12.69)%, (82.25±0.89)%] (P<0.01), while the effect of aspirin (100 mg·kg^-1) was not obvious. The above results suggest that compared with aspirin, salvianolic acid A provided a mild inhibitory effect on platelet aggregation and protected against cerebral ischemia induced by thrombus. Therefore, salvianolic acid A has a good application prospect in the prevention and treatment of thrombotic diseases.

Background: Cardiopulmonary resuscitation (CPR) strategies in COVID-19 patients differ from those in patients suffering from cardiogenic cardiac arrest. During CPR, both healthcare and non-healthcare workers who provide resuscitation are at risk of infection. The Working Group for Expert Consensus on Prevention and Cardiopulmonary Resuscitation for Cardiac Arrest in COVID-19 has developed this Chinese Expert Consensus to guide clinical practice of CPR in COVID-19 patients. Main recommendations: 1) A medical team should be assigned to evaluate severe and critical COVID-19 for early monitoring of cardiac-arrest warning signs. 2) Psychological counseling and treatment are highly recommended, since sympathetic and vagal abnormalities induced by psychological stress from the COVID-19 pandemic can induce cardiac arrest. 3) Healthcare workers should wear personal protective equipment (PPE). 4) Mouth-to-mouth ventilation should be avoided on patients suspected of having or diagnosed with COVID-19. 5) Hands-only chest compression and mechanical chest compression are recommended. 6) Tracheal-intubation procedures should be optimized and tracheal-intubation strategies should be implemented early. 7) CPR should be provided for 20-30 min. 8) Various factors should be taken into consideration such as the interests of patients and family members, ethics, transmission risks, and laws and regulations governing infectious disease control. Changes in management: The following changes or modifications to CPR strategy in COVID-19 patients are proposed: 1) Healthcare workers should wear PPE. 2) Hands-only chest compression and mechanical chest compression can be implemented to reduce or avoid the spread of viruses by aerosols. 3) Both the benefits to patients and the risk of infection should be considered. 4) Hhealthcare workers should be fully aware of and trained in CPR strategies and procedures specifically for patients with COVID-19.