BACKGROUND:Acellular nerve scaffolds have the three-dimensional structure of natural nerves and low immunogenicity,but their effect on long nerve defects is still not ideal.Therefore,it is necessary to construct tissueengineered nerve using acellular nerve and seed cells in order to improve the therapeutic effect.OBJECTIVE:To systemically review the efficacy of combination of acellular nerve grafts (ANGs) and mesenchymal stem cells (MSCs) or Schwann cells (SCs) transplantation in the treatment of sciatic nerve defects in a rat model.METHODS:Randomized controlled trials (RCTs) about the effects of combination of ANGs and MSCs or SCs transplantation for sciatic nerve defects in rats were searched in PubMed,The Cochrane Library,EMbase,CNKI,WanFang and VIP from inception to July 2016.Three reviewers independently screened literature according to the inclusion and exclusion criteria,extracted data,and assessed the risk of bias of included studies.Then,a Meta-analysis was performed using Review Manger5.3 software.RESULTS AND CONCLUSION:A total of 10 RCTs involving 252 rats were included.The results of meta-analysis showed that:compared with the control group (simple acellular nerve scaffold group),the sciatic functional index (SFI) of the combined group (combination of ANGs and MSCs or SCs transplantation) were superior at 2 weeks [SMD=2.73,95％ CI (1.92,3.45),P ＜ 0.000 01],4 weeks [SMD=4.57,95％ CI (3.43,5.70),P ＜ 0.000 01],6 weeks [SMD=1.62,95％CI (0.18,3.06),P=-0.03],8 weeks [SMD=4.90,95％ CI (2.96,6.84),P ＜ 0.000 01] after surgery.The nerve conduction velocity [SMD=1.39,95％ CI (0.99,1.78),P ＜ 0.000 01),latency period (MD=-0.98,95％ CI (-1.19,-0.76),P ＜ 0.000 01],and amplitude [SMD=1.23,95％ CI (0.62,1.85),P ＜ 0.000 1] were superior at 12 weeks after surgery.The myelin sheath thickness was superior at 8 weeks [MD=0.14,95％ CI (0.07,0.21),P ＜ 0.000 1],12 weeks [SMD=1.85,95％ CI (1.63,2.08),P ＜ 0.000 01] and the number of myelinated nerve fibers were superior at 12 weeks [SMD=3.59,95％CI (2.63,4.55),P ＜ 0.000 01] after surgery.The gastrocnemius wet weight was superior at 8 weeks after surgery [SMD=4.22,95％ CI (2.40,6.03),P ＜ 0.000 01].Current evidence indicates that the combination of ANGs and MSCs or SCs can promote the regeneration and functional recovery of the peripheral nerve.Due to the limited quality of the included studies,the above conclusion should be verified by conducting high-quality and large-scale RCTs.

Carotid artery stenosis is one of the primary causes of ischemic stroke.At present,the main surgical treatments for carotid artery stenosis include carotid endarterectomy(CEA)and carotid artery stenting(CAS).In-stent restenosis(ISR)is a long-term complication after CAS,which significantly affects the long-term outcomes of the surgery and the prognosis of patients,with a relatively high incidence in clinical practice.Based on a review of domestic and international studies,the authors provided a comprehensive overview of ISR,covering its pathogenesis,risk factors,treatment options,and the latest research developments,in order to provide clinicians with guidance for the diagnosis and treatment of ISR.

Objective:To explore the relationship between pathogens in the olfactory cleft area and olfactory disorders in patients with upper respiratory inflammation (URI) during the prevention and control of 2019 novel coronavirus disease (COVID-19).Methods:A total of 234 URI patients including acute upper respiratory infection, chronic rhinosinusitis (CRS), allergic rhinitis (AR) were continuously selected from September 2020 to March 2021 in Beijing Anzhen Hospital and 98 healthy adults were enrolled as controls. The secretions from the olfactory cleft of all subjects were collected with nasal swabs under nasal endoscopy. Multiple real-time fluorescent quantitative polymerase chain reaction detection method was used to detect nucleic acids of 33 types of respiratory pathogenic microorganism. Sniffin′ Sticks olfactory test was performed on all patients with URI. URI patients with olfactory dysfunction were followed up for 9 (8, 10) months ( M ( Q1, Q3)). SPSS 20.0 software was used for statistical analysis. Results:Among the 98 controls, 9 (9.18%) were positive for pathogenic microorganisms, including 1 (1.02%) rhinovirus, 1 (1.02%) parainfluenza virus type 3, 3 (3.06%) enterovirus, 1 (1.02%) staphylococcus aureus and 3 (3.06%) Moraxella catarrhalis. Among the 234 URI patients, 111 (47.44%) had olfactory disorders and 123 (52.56%) had normal sense of smell. In the olfactory disorder group (111 cases), 38 cases (34.23%) were positive for pathogenic microorganisms, and 4 cases (3.60%) were mixed infection, including 11 cases of rhinovirus (9.91%), 5 cases of coronavirus 229E (4.50%), 2 cases of coronavirus OC43/NL63 (1.80%), 3 cases of parainfluenza virus type 1 (2.70%), 2 cases of enterovirus (1.80%), 1 case of influenza B virus type BV (0.90%), 11 cases of Staphylococcus aureus (9.91%), 7 cases of Moraxella catarrhalis (6.31%), and 1 case of Klebsiella pneumoniae (0.90%). In the normal smell group (123 cases), 18 cases (14.63%) were positive for pathogenic microorganisms, and 1 case (0.81%) was mixed infection, including 3 cases of rhinovirus (2.44%), 4 cases of coronavirus 229E (3.25%), 1 case of Influenza virus type 3 (0.81%), 3 cases of enterovirus (2.44%), 3 cases of Staphylococcus aureus (2.44%), 4 cases of Moraxella catarrhalis (3.25%), and 1 case of Klebsiella pneumoniae (0.81%). Univariate analysis between the two groups found that there were significant differences in the detection rate of pathogenic microorganisms, rhinovirus and Staphylococcus aureus between the groups (all P<0.05). The detection rate of parainfluenza virus type 1, Staphylococcus aureus, and rhinovirus were different between the patients with olfactory disorder and normal olfactory function in the three subgroups of acute upper respiratory tract infection, CRS and AR, respectively (χ 2 value was 3.88, 4.53 and 4.73, respectively, all P<0.05). During the follow-up period, among the 111 patients with olfactory disorder, 71 (63.96%) patients′ olfactory function returned to normal, 32 (28.83%) patients′ olfactory function improved but not completely returned to normal, 8 (7.21%) patients′ olfactory function did not improve. Conclusions:During the prevention and control of COVID-19, rhinovirus or Staphylococcus aureus infection or colonization of URI patients is closely related to olfactory disorders. Parainfluenza virus type 1 infection can cause relatively persistent olfactory disorders in patients with acute upper respiratory tract infection. Staphylococcus aureus and rhinovirus colonization are related to the occurrence of olfactory dysfunction in CRS and AR patients respectively.

OBJECTIVE: To carry out genetic and metabolite analysis for an infant with cerebral creatine deficiency syndrome type 2 (CCDS2). METHODS: Clinical data of the child was collected. Whole-exome sequencing was carried out to identify potential variants by next generation sequencing. Candidate variants were confirmed by Sanger sequencing. Metabolites were determined by tandem mass spectrometry and magnetic resonance spectroscopy. Treatment was carried out following the diagnosis and genetic counseling for the affected family. RESULTS: Two novel heterozygous variants (c.289delC and c.392-1G>C) of the GAMT gene were identified in the proband, which were respectively inherited from her father and mother. In silico analysis suggested both variants to be pathogenic. Creatine (Cr) level of the child was very low, and cerebral guanidinoacetate (GAA) level was slightly increased. But both had recovered to normal in two weeks, and cerebral Cr level was significantly improved after two months. Intellectual and motor development of the child were significantly improved. CONCLUSION The child was diagnosed with CCDS type 2, for which pathogenic variants of the GAMT gene may be accountable. Treatment has attained a satisfactory effect for the patient.

Objective:Abnormal angiogenesis is an important hallmark of HCC. Ectopic miR-375 overexpression led to repression of proliferation, migration, invasion, and colony formation, and it induced apoptosis in hepatoma cells as well. In this study, we explored the effect of miR-375 on HCC angiogenesis. Methods:We evaluated the antiangiogenic effects of miR-375 using human umbilical vein endothelial cells, tube formation assays, rat aortic ring sprouting assays, and chicken chorioallantoic membrane assays. Bioinformatics software was used to predict the downstream target gene of miR-375. MiR-375 regulation to target genes was explored by overexpres-sion and knockdown of miR-375 in hepatoma cells. Luciferase assay was performed to confirm its molecular mechanism. Rescue assay of target gene was further used to prove that miR-375 inhibited HCC angiogenesis by directly regulating its target gene. Results:MiR-375 inhibited HCC angiogenesis. Platelet-derived growth factor-C (PDGFC) was a potential target gene of miR-375. MiR-375 inhibited PDGFC expression in hepatoma cells by targeting its 3′-UTR. MiR-375 exerted its antiangiogenic effect partially by PDGFC inhibition. Conclusion:MiR-375 repressed tumor angiogenesis by targeting PDGFC in HCC.

Objective To observe biomechanical characteristics and advantages of the self-developed anatomical locking plate of sternoclavicular joint by comparison with the radial distal oblique T-shaped locking plate and sternoclavicular hook plate. Methods Nine embalming and moistening adult corpses were selected, including 6 males and 3 females. Model of complete dislocation of the sternoclavicular joint caused by complete removal of the sternoclavicular joint specimen. The bilateral sternoclavicular joints of 9 specimen models were randomly numbered, matched and divided into Group A(experimental group, sternoclavicular joint anatomical locking plate), Group B(control group 1, the radial distal oblique T-shaped locking plate) and Group C(control group 2, sternoclavicular hook plate), with 6 sternoclavicular joints in each group. All specimens were placed with steel plates on both sides and fixed on the universal mechanical test machine. Three biomechanical experiments were carried out, including loading of distal clavicle, torsion of distal clavicle and anti-pull out of sternum handle screw. Results Distal clavicle loading test: the load-displacement of specimens in three groups showed a linear relationship. The compressive deformation resistance in experimental group was stronger than that in two control groups. Distal clavicle torsion test: the relationship between torque and torsion angle was linear. The torsional deformation resistance in experimental group was stronger than that in two control groups. Anti-pullout test of sternum handle screw: there was a significant difference in the maximum anti-pullout force of sternum handle screw among the three groups (P＜0.05). The anti-pullout performance of the sternum handle screw in the experimental group was better than that in the two control groups. Conclusions The self-developed sternoclavicular joint anatomical locking plate is superior to the oblique T-shaped locking plate of distal radius and the plate of sternoclavicular hook in terms of anti-compression, anti-torsion and anti-pullout of sternoclavicular screw, so as to provide an ideal internal fixation device for the treatment of fracture and dislocation of sternoclavicular joint.