ObjectiveTo investigate the levels of serum antibodies against novel coronavirus （SARS-CoV-2） in healthcare workers after one month of natural infection， to explore the influencing factors and their correlations with the levels of antibodies， and to provide reference for strengthening the protection of healthcare workers and preventive intervention in Pudong New Area in Shanghai. MethodsVenous blood samples were collected from 1 102 medical staff in Pudong hospitals one month after infection. The serum levels of new coronavirus specific antibodies IgM， IgG and neutralizing antibodies were detected by chemiluminescent immunoassay. The information of gender， age， position， infection severity， vaccination， basic diseases and use of immunosuppressants were obtained by questionnaire to explore the influencing factors and their correlation with the antibody level. ResultsOne month after natural infection， 99.00% （1 091/1 102） of the subjects were found to be positive for IgG antibody against the new coronavirus， 17.79% （196/1 102） of the subjects were IgM antibody positive， and 99.00% （1 091/1 102） of the samples were positive for the neutralizing antibody. The level of antibody might be influenced by the severity of infection， the time of the last dose of vaccination， and the long-term use of immunosuppressants. The more severe the disease， the stronger the neutralizing antibody response. The antibody level in the people who received the final dose of vaccine within 6 months was higher than that of the people who received the vaccine 6 months ago， and the difference was statistically significant. The antibody levels were low in the subjects who received long-term immunosuppressants. ConclusionThe specific IgM， IgG and neutralizing antibody were found， one month after infection， in the medical workers in Pudong New Area， Shanghai， and the antibody titers were high， which had a good protective effect. The antibody level of the people who were vaccinated within 6 months was higher， it is recommended that people who receive the last vacination more than 6 months should be re-vaccinated with the booster vaccine， to improve the autoimmunity against the novel coronavirus.

Objective:To evaluate the clinical efficacy of pushing reduction with our self-designed spinal fracture reduction device in the treatment of A3N0/1 thoracolumbar fractures.Methods:A retrospective study was conducted to analyze the medical records of 53 patients who had undergone surgery for thoracolumbar vertebrae fracture at Department of Minimally Invasive Spine Surgery, Zhengzhou Orthopedic Hospital from January 2019 to January 2022. All patients were treated by internal fixation via the Wiltse approach and bone grafting through the pedicle of the injured vertebrae. Clinical data: 35 males and 18 females; age: (37.8±10.2) years; injured segments: 23 cases at the thoracic spine and 30 cases at the lumbar spine; time from injury to surgery: (3.3±1.5) days. According to whether our self-designed spinal fracture reduction device was used or not, the patients were assigned into group A (23 cases) in which the injured vertebrae were pushed and reduced using our novel spinal fracture reduction device after vertebral distraction reduction by the pedicle screw and group B (30 cases) in which the injured vertebrae were distracted and reduced using the pedicle screw alone. The operation time, intraoperative blood loss and complications were compared between the 2 groups. The anterior vertebral body height ratio (AVBHr), middle vertebral body height ratio (MVBHr), posterior vertebral body height ratio (PVBHr), Cobb angle of the injured vertebra, visual analogue scale (VAS) and Oswestry disability index (ODI) at preoperation, postoperative 3 and 6 months, and the last follow-up were compared between the 2 groups.Results:There was no statistically significant difference in the preoperative general data between the 2 groups, indicating comparability ( P>0.05). All patients were followed up for (16.3±5.9) months. All incisions healed at one stage postoperatively without any related complications. The operation time in group A was significantly longer than that in group B [(115.1±16.6) min. versus (101.0±11.5) min.], the intraoperative blood loss in group A was significantly greater than that in group B [(136.5±17.0) mL versus (121.6±19.8) mL], the MVBHr at postoperative 3 months in group A (93.9%±4.0%) was significantly better than that in group B (83.3%±7.6%), and the MVBHr, AVBHr, Cobb angle, VAS, and ODI at the last follow-up in group A [86.6%±5.5%, 89.8%±4.1%, 4°(4°, 6°), 1 (0, 1) point, and 4.7%±2.0%] were significantly better than those in group B [78.0% (74.0%, 79.0%), 84.5%±4.9%, 12.2°±3.3°, 2 (1, 3) points, and 7.3%±2.7%] (all P<0.05). However, there was no statistically significant difference in PVBHr between the 2 groups at postoperative 3 months or at the last follow-up ( P>0.05). Conclusion:In the treatment of A3N0/1 thoracolumbar fractures, pushing reduction with our self-designed spinal fracture reduction device can directly and effectively reduce the fracture zone of the injured vertebra, which is conducive to maintaining postoperative vertebral reduction, reducing vertebral height loss and kyphotic deformity at a later stage, relieving lumbar pain and improving lumbar spine function.

Objective    To compare the long-term durability of valved homograft conduit (VHC) in patients with Ross and non-Ross right ventricular outflow tract (RVOT) reconstruction. Methods    Patients who underwent RVOT reconstruction using VHC in Fuwai Hospital from January 2008 to October 2020 were retrospectively included. Patients who received Ross RVOT reconstruction were allocated to a Ross group and patients who received non-Ross RVOT reconstruction were allocated to a non-Ross group. The survival and reintervention-free rates of the two groups were evaluated with the Kaplan-Meier survival curve and log-rank test. The propensity score matching analysis was performed on the patients who completed ultrasound follow-up in the two groups, and the VHC dysfunction-free rate was compared between the two groups. Results    A total of 243 patients were enrolled, including 142 males and 101 females, with a median age of 6 years (4 months to 56 years). There were 77 patients in the ROSS group and 166 patients (168 operations) in the non-ROSS group. The cardiopulmonary bypass time in the Ross group was shorter than that in the non-Ross group (175.4±45.6 min vs. 200.1±83.5 min, P=0.003). Five patients in the non-Ross group died early after the operation. The follow-up was available in 231 patients (93.1%), with the average follow-up time of 61.7±44.4 months. During the follow-up, 5 patients in the non-Ross group died. The 12-year survival rate was 100.0% in the Ross group and 93.2% in the non-Ross group (log-rank, P=0.026). In addition, 1 patient in the Ross group and 7 patients in the non-Ross group received VHC reintervention. There was no significant difference in the reintervention-free rate between the two groups (log-rank, P=0.096). Among the 73 patients in the Ross group and 147 patients in non-Ross group who were followed up by ultrasound after discharge, 45 patients (20.5%) developed VHC dysfunction. Before matching, the long-term durability of VHC in the Ross group was better than that in non-Ross group (10-year VHC dysfunction-free rate: 66.6% vs. 37.1%, log-rank, P=0.025). After the propensity score matching, 64 patients included in each group, and there was no statistical difference in the long-term durability of VHC between the two groups (10-year VHC dysfunction-free rate: 76.3% vs. 43.0%, log-rank, P=0.065). In the subgroup analysis, the 10-year VHC dysfunction-free rate in the Ross group was higher than that in the non-Ross group (71.0% vs. 20.0%, log-rank, P=0.032) among patients aged<6 years at surgery. However, there was no significant difference in the 10-year VHC dysfunction-free rate between the two groups (53.7% vs. 56.7%, log-rank, P=0.218) among patients aged ≥6 years at surgery. Conclusion    After the propensity score matching analysis, the long-term durability of VHC has no significant difference between the Ross group and non-Ross group. The long-term durability of VHC after Ross surgery is superior to that of non-Ross surgery in patients aged<6 years at surgery.

Objective    To evaluate the clinical outcome of valved homograft conduits (VHC) used for right ventricular outflow tract (RVOT) reconstruction in Fuwai Hospital in recent 13 years, and explore the factors influencing the long-term durability of VHC. Methods    Clinical data of patients using VHC for RVOT reconstruction in Fuwai Hospital from November 2007 to October 2020 were retrospectively analyzed. The Kaplan-Meier survival curve was used to evaluate survival, VHC reintervention and VHC dysfunction. Cox proportional risk regression model was used to analyze the risk factors for VHC dysfunction. Results    Finally 251 patients were enrolled, including 145 males and 106 females. The median age at surgery was 6.0 (0.3-67.0) years. Early death occurred in 5 (2.0%) patients. The follow-up was available for 239 (95.2%) patients, with the follow-up time of 0.3-160.0 (61.3±45.4) months. Five patients died during the follow-up, and the 1-year, 6-year, and 13-year survival rates were 96.6%, 95.5% and 95.5%, respectively. Eight patients received VHC reintervention during the follow-up, and freedom rates from VHC reintervention were 100.0%, 97.1% and 82.4% at 1 year, 6 years and 13 years, respectively. A total of 226 patients were followed up by echocardiography after discharge, with the follow-up time of 0.2-138.0 (48.5±40.5) months. During the follow-up, 46 (20.4%) patients developed VHC dysfunction, and freedom rates from VHC dysfunction at 1 year, 5 years, and 10 years were 92.6%, 79.6% and 59.3%, respectively. Univariate Cox regression analysis showed that age<6 years and VHC diameter<19 mm were risk factors for VHC dysfunction (P=0.029, 0.026), but multivariate regression analysis only indicated that age<6 years was an independent risk factor for VHC dysfunction (P=0.034). Conclusion    The early and late outcomes of VHC used for RVOT reconstruction are satisfactory, and the long-term durability of VHC is also optimal. In addition, age<6 years is an independent risk factor for VHC dysfunction.

Objective    To summarize the surgical experience of infants with transposition of the great arteries (TGA) and intramural coronary artery (IMCA) in our center, and analyze the early and mid-term outcomes. Methods    We retrospectively analyzed the clinical data of 384 infants with TGA undergoing arterial switch operation (ASO) from June 2010 to December 2018 at Fuwai Hospital. According to operative records, 21 (5.5%) infants had IMCA, among whom 20 were males, with a median age of 33 (9-319) d. Coronary transfer using double coronary buttons with unroofed intramural course was performed in all 21 infants. Results    There was no statistical difference in the early mortality after ASO between infants with IMCA and infants with normal coronary anatomy (9.5% vs. 3.0%, P=0.15). In the IMCA group, 2 dead patients presented inadequate coronary artery perfusion after first aortic unclamping. In addition, 1 patient underwent extracorporeal membrane pulmonary support for myocardial dysfunction. The follow-up was available for all 19 survivors, with an average follow-up time of 29.0-120.0 (74.8±27.3) months. During the follow-up, all patients had no obvious symptoms, death, reoperation, or coronary complications. One patient developed moderate pulmonary valve regurgitation and another patient developed distal stenosis of the right pulmonary artery. Conclusion    For infants with TGA and IMCA, coronary transfer using double coronary buttons with unroofed intramural course is a safe and reliable technique, with satisfactory early and mid-term outcomes.

Objective:To investigate the clinical effect of medial plantar flap combined with free groin flap in the reconstruction of heel defect.Methods:The patients with heel skin and soft tissue defects admitted to the Department of Burns & Plastic and Hand & Foot Surgery of Yulin No.2 Hospital from October 2015 to December 2020 were retrospectively analyzed. After emergency debridement, a plantar medial island flap was used to repair the foot heel defect, a free groin flap was used to repair the medial plantar donor site, and the groin donor site was closed primarily. Postoperatively routine anti-infection, spasmolysis, anticoagulation, expanding treatment were performed after the procedure. The blood supply, survival of the flap, and the healing of the donor area of the flap were observed. The shape and function of the heel were observed in follow-up.Results:Eight patients were enrolled, including 7 males and 1 female, aged from 20 to 71 years, with an average of 32.2 years. There were 5 cases of heel trauma, 1 case of heel squamous cell carcinoma, 1 case of heel frostbite, and 1 case of heel ulcer. The wound area of the heel was 4 cm×3 cm-7 cm×6 cm. The surgical procedure was smooth, and the incision range of the heel island flap and groin flap was 0.5-1.0 cm larger than that of the heel wound. All 8 patients had primary healing after the operation. Follow-up for 3-12 months showed that all patients were satisfied with heel shape, sensory function and walking function. There was no depression, scar hyperplasia, and contracture in the medial plantar donor area, and no local skin ulcer. There is only a linear scar in the groin donor area.Conclusions:Medial plantar island flap combined with a free groin flap can repair the defect of the heel, and the affected foot has good healing, certain sensory function, and satisfactory curative effect.

Objective:To investigate the clinical effect of medial plantar flap combined with free groin flap in the reconstruction of heel defect.Methods:The patients with heel skin and soft tissue defects admitted to the Department of Burns & Plastic and Hand & Foot Surgery of Yulin No.2 Hospital from October 2015 to December 2020 were retrospectively analyzed. After emergency debridement, a plantar medial island flap was used to repair the foot heel defect, a free groin flap was used to repair the medial plantar donor site, and the groin donor site was closed primarily. Postoperatively routine anti-infection, spasmolysis, anticoagulation, expanding treatment were performed after the procedure. The blood supply, survival of the flap, and the healing of the donor area of the flap were observed. The shape and function of the heel were observed in follow-up.Results:Eight patients were enrolled, including 7 males and 1 female, aged from 20 to 71 years, with an average of 32.2 years. There were 5 cases of heel trauma, 1 case of heel squamous cell carcinoma, 1 case of heel frostbite, and 1 case of heel ulcer. The wound area of the heel was 4 cm×3 cm-7 cm×6 cm. The surgical procedure was smooth, and the incision range of the heel island flap and groin flap was 0.5-1.0 cm larger than that of the heel wound. All 8 patients had primary healing after the operation. Follow-up for 3-12 months showed that all patients were satisfied with heel shape, sensory function and walking function. There was no depression, scar hyperplasia, and contracture in the medial plantar donor area, and no local skin ulcer. There is only a linear scar in the groin donor area.Conclusions:Medial plantar island flap combined with a free groin flap can repair the defect of the heel, and the affected foot has good healing, certain sensory function, and satisfactory curative effect.

Objective: To explore the clinical effect of negative pressure wound therapy (NPWT) in emergency limb-salvage operation of destructive injury of limb. Methods: From July 2014 to December 2017, 43 patients with destructive injury of limb in one side conformed to the inclusion criteria were admitted to our hospital. The patients were divided to NPWT group of 24 patients [ 21 males and 3 females, aged (38±10) years] and routine dressing change group of 19 patients [ 17 males and 2 females, aged (37±10) years] according to their treatment methods. After the emergency debridement, fracture external fixation, neurovascular exploration, and microsurgical repair were performed, NPWT were applied on wounds of patients in NPWT group and routine dressing change treatment on wounds of patients in routine dressing change group. On 7 to 10 days after the emergency operation, incidence of arterial embolism of patients in the two groups were calculated, and condition of wound infection of patients in the two groups were observed. Complete wound healing time and survival condition of limb were recorded. Data were processed with independent sample t test or chi-square test. Results: Incidence of arterial embolism of patients in NPWT group on 7 to 10 days after the emergency operation was 6.67% (3/45), which was close to 5.56% (2/36) of patients in routine dressing change group (χ²=0.043, P>0.05). There was 1 patient with wound infection in NPWT group on 7 to 10 days after the emergency operation, obviously less than 6 patients in routine dressing change group (χ²=5.847, P<0.05). Complete wound healing time of patients in NPWT group was (30±4) d, significantly shorter than (36±8) d of patients in routine dressing change group (t=2.813, P<0.01). Limbs of 24 patients in NPWT group survived, which was close to 18 patients in routine dressing change group (χ²=1.293, P>0.05). Conclusions NPWT can significantly reduce tthe wound infection rate and shorten the time of wound healing of limb with destructive injury after emergency operation, which is worthy of popularization in clinic.

Objective: To study the clinical effect of relaying peroneal artery perforator flap on anterior middle and lower tibia and donor-site defects repair. Methods: From July 2014 to June 2017, 12 patients were included. The anterior middle-lower tibia soft tissue defects and the primary donor-sites were repaired by relaying peroneal artery perforator flaps, and the second donor-sites were directly closed. The size of anterior middle-lower tibia defects ranged from 5 cm × 3 cm to 13 cm × 9 cm. The flaps repairing the wounds ranged from 6 cm × 4 cm to 14 cm × 10 cm in size. The flaps restoring the first donor-site ranged from 5 cm×4 cm to 10 cm×6 cm in size. The clinical effect was evaluated by observing the appearance of the recipient sites and the donor sites. Results: All the flaps survived uneventfully. All patients were followed up for 8-36 months (average 20 months). The flaps remained with good texture and color. The second donor-sites only left linear scar, which do not affect the overall appearance of limb. Conclusions The blood supply of relaying peroneal artery perforator is reliable without any disturbing of the main artery. The flap located on the lateral of the calf. The relaying peroneal artery perforator flap can repair the soft tissue defect at the anterior middle-lower tibia and improve the appearance of the first donor-site.

Objective To study the roles of miR-20a in lipopolysaccharide induced inflammation of A549 cells and the possible mechanisms.Method The miR-20a mimic/inhibitor were transfected into A549 cells, and the cells were stimulated using lipopolysaccharide for 24 h.Interleukin-6 ( IL-6) and IL-8 were detected at mRNA level and protein level using real-time PCR and ELISA method , respectively.Protein expression of apoptosis signal regulating kinase 1 (ASK1)、P38、P-P38、JNK and P-JNK were detected using Western blot. Result Compared to mimic negative control group , the levels of mRNA and protein expression of IL-6 and IL-8 in the mimic group were all significantly decreased ( P<0.05).Compared to inhibitor negative control group , the levels of mRNA and protein expression of IL-6 and IL-8 in the inhibitor group were all significantly increased (P<0.05).The levels of ASK1, P-P38 and P-JNK protein in the mimic group were significantly lower than the mimic negative control group (P<0.05);the level of protein expression of ASK1, P-P38 and P-JNK in the inhibitor group were all higher than the inhibitor negative control group (P<0.05).Conclusion The regulation of ASK1 by miR-20a may play an important role in the inflammation process of acute respiratory distress syndrome .