AIM:To construct a prokaryotic expression system of staphylococcal enterotoxin A(SEA)gene and determine the effects of the recombinant expression product rSEA in promoting lymphocyte proliferation and inhibiting tumor cell growth.METHODS:PCR was used to amplify entire SEA gene of S.aureus strain ATCC13565.The cloned SEA gene was sequenced after T-A cloning.SDS-PAGE was applied to measure the output of rSEA expressed by pET32a-SEA-E.coli BL21DE3.Ni-NTA affinity chromatography was performed to extract rSEA.Cytotoxicity of rSEA to Vero cells was detected using TCID_ 50 titration method and then the value of TCIC_ 50 was determined.MTT colorimetry was established to examine the effects of rSEA at different dosages on proliferation of mouse splenocytes and human peripheral blood mononuclear cells(PBMC)as well as on growth of HepG2 cells and HeLa cells in vitro.RESULTS:In comparison with the published corresponding sequences,similarities of the nucleotide and putative amino acid sequences of the cloned SEA gene were 100%.The output of rSEA was approximate 25% of the total bacterial proteins.rSEA had a cytotoxicity with TCIC_ 50 of 3.14 ?g to Vero cells.1.0-20.0 mg/L rSEA showed the significant effects of promoting proliferation of mouse splenocytes and human PBMC(P

Objective To investigate the curative effect of damage control theory in treating severe polytrauma patients combined with bone and joint injury. Methods A retrospective study was done on data including complication, death rate, fracture healing and joint function recovery of 63 patients with severe polytrauma combined with bone and joint injury( average ISS ≥27 points) admitted to our hospital from January 2006 to June 2009. Results Of all the patients, 57 shock patients were cured,three died of hemorrhagic shock within two hours after admission and one patient died of severe traumatic brain injury 11 hours after admission. One patient died of ARDS at 24 hours postoperatively and one died of multiple organ failure at day 6 after injury. Fracture healing was achieved in 52 patients, with satisfactory recovery of the limb function. Amputation was performed in two patients and three patients had mild claudication and pain walking. Conclusion Damage control strategy has great clinical significance in guidance of treatment of severe polytrauma combined with bone and joint injury.

Objective To investigate the clinical characteristics of cervical spine injury associated with chest injury by contrast with simple cervical spine injury.Methods A retrospective analysis was performed on records of 116 patients with cervical spine injury hospitalized from March 2009 to September 2014.There were 65 patients with simple cervical spine injury (simple injury group) and 51 patients with associated chest injury (associated injury group).Data recorded were the causes of injury, injury segment, treatment choices (tracheotomy rate, mechanical ventilation use and non-operative treatment), treatment time (operation rate at different time, time from injury to operation and length of hospital stay) , complications (electrolyte disorder, respiratory infection, respiratory dysfunction or failure, urinary tract infection, gastrointestinal bleeding and multiple organ dysfunction syndrome), and treatment outcome.Results The main cause of injury for the two groups was high falling.Lower cervical segment was the most likely to be affected.Significant differences were detected between the simple injury group and associated injury group with regard to tracheotomy rate (63％ vs.42％), rate of mechanical ventilation (41％ vs.25％), rate of early surgery (29％ vs.58％), rate of delayed surgery (69％ vs.30％), time from injury to operation [(7.2 ± 3.7) d vs.(3.1 ± 1.3) d], length of hospital stay [(22.6-± 5.5) d vs.(17.3 ± 3.7)d], electrolyte disorder rate (35％ vs.17％), incidence of respiratory system infection (55％ vs.35％), and respiratory dysfunction (43％ vs.25％) (P ＜0.05).After treatment, American Spinal Injury Association (ASIA) scale for grade D was significantly lower in associated injury group than in simple injury group (25％ vs.39％ P ＜ 0.05).Conclusion Cervical spine injury associated with chest injury is severe injury, often requiring tracheotomy and mechanical ventilation, and demonstrates difficulties to be effectively treated in the early phase, long hospitalization, various complications and high morbidity.

[ABSTRACT]OBJECTIVETo estimate different dimensions of maxillary sinus measured on cone-beam computerized tomography (cone-beam CT), and determine the differences in side and gender.METHODScone-beam CT image data from 200 normal adults was selected and analyzed by Invivo Dental software. The craniocaudal diameter, anteroposterior diameter, width and volume of maxillary sinus were measured as well as the thickness of the orbital floor. Statistical analysis was performed with SPSS 11.5.RESULTSThere were no statistically significant differences in the craniocaudal diameter, anteroposterior diameter, width and volume of maxillary sinus between sides (P>0.05, respectively). Significant differences were noted in the craniocaudal diameter and volume of bilateral maxillary sinus and the width of right maxillary sinus based on gender (P<0.05, respectively). There were no significant differences in the width of left maxillary sinus, the anteroposterior diameter of bilateral maxillary sinus and the osseous thickness of the orbital floor (P>0.05, respectively).CONCLUSIONOur findings indicate that cone-beam CT can be used to measure different dimensions of maxillary sinus and provide imaging anatomical data for clinical treatment.

The rotator cuff injury is a kind of chronic tendon disease related to overuse injury. The main clinical manifestations of this disease include shoulder pain and dysfunction，which seriously affects people 's life quality and work capability. Although previous studies have shown that inflammation and de- generation of collagen matrix are closely related to the occurrence and development of this disease，the pathogenesis of the disease is still unclear. In this study，the authors review the pathologic mechanisms of rotator cuff injuries from aspects of oxidative stress，inflammation，macrophage and non-coding RNA so as to provide a reference for subsequent research and treatment.

Objective:To investigate the clinical effect of early arthroscopic shoulder treatment of moderate full-thickness tear of the supraspinatus tendon.Methods:A retrospective case control study was conducted to analyze the clinical data of 43 patients with moderate full-thickness supraspinatus tendon tear admitted to First Affiliated Hospital of Xi 'an Jiaotong University from January 2018 to June 2020，including 17 males and 26 females，aged from 41 to 68 years［（55.9±8.2）years］. All patients had arthroscopic shoulder supraspinatus tendon suture and acromioplasty，including 22 patients underwent surgery within 1 month after persistent shoulder pain and motion limitation in early group and 21 patients between 1 month and 3 months in late group. The duration of operation and intraoperative blood loss were recorded. The visual analogue scale（VAS），American Shoulder and Elbow Society（ASES）score and Constant-Murley score were assessed before operation and at postoperative 3 weeks，6 weeks，3 months and 6 months. The complications were detected with 6 months after operation. Results:All patients were followed up for 6-7 months［（6.4±0.4）months］. There was no statistical significance in operation duration and intraoperative blood loss between the two groups（ P>0.05）. At 3 weeks，6 weeks，3 months and 6 months after operation，there showed significant decrease of VAS but significant increase of ASES and Constant-Murley scores compared to preoperation（ P<0.05）. At 3 weeks and 6 weeks after operation，the VAS in early group［（4.4±0.9）points，（3.7±0.8）points］was lower than that in late group［（5.5±1.0）points，（4.8±1.1）points］；while the ASES score［（49.1±4.6）points，（56.8±4.1）points］and Constant-Murley score［（54.1±4.8）points，（64.1±4.4）points］in early group were higher than those in late group［ASES score：（45.2±5.4）points，（50.3±5.4）points；Constant-Murley score：（50.5±3.3）points，（58.2±3.9）points］（ P<0.05）. At 3 months and 6 months after operation，the two groups showed no statistical significance in these scores. There were no postoperative complications such as infection or nerve injury in both group within 6 months. Conclusion:For moderate full-thickness tear of the supraspinatus tendon，arthroscopic shoulder surgery performed within 1 month after persistent shoulder pain and motion limitation can achieve better pain relief and faster functional rehabilitation in the short term compared with surgery performed 1-3 months later.

Rotator cuff injury often leads to shoulder pain and dysfunction. For the injured rotator cuff tendon without continuous interruption, conservative treatment is often used. However, the shoulder is used frequent in daily life, which makes that the rotator cuff injury generally shows gradual aggravation and eventually progresses to complete tear due to poor blood supply of the rotator cuff tendon tissue and weak repair ability. In order to reverse the pathophysiological changes after rotator cuff injury and promote the repair of injured rotator cuff tendon, a series of conservative treatments for rotator cuff injury have been explored. Extracorporeal shock wave therapy (ESWT) is one of the representative treatments, but its molecular biological mechanism in promoting rotator cuff repair is still unclear. Therefore, the authors review the progress of ESWT for rotator cuff injury from aspects of the molecular biological mechanism and clinical application status, so as to provide a reference for future researches and clinical application of ESWT.

The spatiotemporal distribution of growth factors in bone tissue-engineered repair and reconstruction is critical. Growth factors can be used in bone tissue engineering through different encapsulation methods. Different encapsulation methods make growth factors have different release kinetics. At present, the common physical entrapment, easily degradable carrier and simple spatial structure usually result in poor sustained release of growth factors by burst release. The optimization of release methods of growth factors enables their release at different times and spaces in a biomimetric manner, which is conducive to improving the effect of tissue repair and avoiding the adverse effects of excessive factors. Starting from the necessity of spatiotemporal sustained release of growth factors, the authors summarize growth factors can attain spatiotemporal sustained release by being directly immobilized on the surface of the carrier, encapsulated in the carrier, encapsulated in the microparticles and encapsulated in the carrier by the microparticles and review the spatiotemporal sustained release of growth factors in different encapsulation methods, so as to provide a reference for optimizing spatiotemporal release of growth factor in bone tissue engineering.