BACKGROUND:Development of neural crest cels, which is regulated by various genes, plays an important role in the formation of central nervous system, heart, craniofacial organs and other tissues. However, the relationship among these genes is unclear. OBJECTIVE:To investigate the molecular regulatory networks involved in the process of neural crest cel development based on a bioinformatic analysis. METHODS:Totaly 500 differentialy expressed genes during the process ofneural crest cel development were obtained from the GEO on-line database. Then the DAVID and STRING on-line databases were used to evaluate the relationship among these genes. RESULTS AND CONCLUSION:Totaly 500 differentialy expressed genes during theprocess of neural crest cel development could be enriched into different subgroups based on the analysis of DAVID database, including “transforming growth factor β signal pathway”, “WNT signal pathway”, “homeobox gene” , “neural crest cel differentiation” and “neural tube development”. Additionaly, 12 genes molecular networks were built based on the analysis of STRING database, such as DLX5, MSX2, SNAIL2, PAX7, SHH, SOX9, NOG, GSC, KAL1, bone morphogenetic protein 5, fibroblast growth factor 8 and WNT3a.These genes exhibited interactions by co-expression, activation and antagonism. Therefore, many genes involved in the process of neural crest cel development were interacted and formed the networks. These findings imply that we should understand these neural crest-related diseases from a holistic view of the signaling pathway and molecular regulatory networks.

Objective To investigate the mecA gene expression lvevl in clinically isolated Staphylococcus aureus (SA) strains and its correlation with drug resistance .Methods Clinically isolated 186 SA strains were collected .The K-P method was adopted to conduct the durg sensitivity test .Then DNA of these strains was extracted and the mecA gene was amplified by using PCR .Results The detection rate of methicillin-resistant SA(MRSA) was 30 .65% (57/186) ,the positive mecA gene was detected in 56 strains of MRSA and 10 strains of methicillin susceptible S .aureus(MSSA) among 129 strains of MSSA ;except susceptible to vancomycin and linezolid ,the resistance rate of MRSA to ther antibacterial durgs were higher than that of MSSA ,the resistance rate to antibac-terial durgs in the strains carrying mecA gene was higher than that in the strains without carrying mecA gene ,ther difference be-tween them had statistical significance (P<0 .05) .Conclusion Clinically isolated SA strains carrying mecA gene are resistant to multiple antibacterial drugs ,which indicating that mecA gene play an important role in SA drug-resistance mechanism .

Objective To investigate effect of emodin on cell membrane, protein and nucleic acid synthesis of MRSA41577, and systematically investigate the anti-bacterial mechanism of emodin.Methods TTC assay was used to detected the anti-bacterial activity of emodin on MRSA 41577. Conductivity and macromolecular were detected to investigate the effect of emodin on MRSA41577 cell membrane .SDS-PAGE was used to detect the effect of emodin on the soluble protein synthesis.DAPI staining was used to detect the effect of emodin on nucleic acid synthesis.UV-visible spectrophotometric was used to detected the interaction between emodin and DNA.ResuIts Emodin has significant inhibitory activity on MRSA41577, and the minimum inhibitory concentration was 8μg/mL.After treated with 8 μg/mL emodin for 6h, compared with control group, the macromolecular and conductivity improved (71.48 ±0.026)% (P<0.01) and (2.39 ±0.102)%(P<0.05), sepreatly.Compared with control, after treated with 8μg/ml emodin for 16h,the protein reduced 32.8%, and the contents of DNA and RNA reduced (4.82 ±1.06)%(P<0.05,) and (6.67 ±0.36)%(P<0.053).The UV-visible spectrophotometric results indicated that emodin could integrate with DNA through hydrogen bond.ConcIusion The anti-bacterial mechanism of emodin mainly through damage the cell membrane , inhibit the replication and transcription of DNA through hydrogen bond , inhibit the synthesis of protein, and thus inhibit the biological function of bacteria.

Objective To observe the clinical efficacy of HMME-SDT therapy for the treatment of hypertrophic scar (HS) of rabbit ear.Methods 60 white rabbits were randomly divided into five groups.The model group and HMME-SDT treatment group were used to establish the models of hypertrophic scar in ears.Results The effect of HMME-SDT on the fibroblastic density in the hypertrophic scarring models was observed in rabbit ears.The HMME-SDT could lower the fibroblastic density,compared with the model group,with significant difference (P＜ 0.05).The effect of HMME-SDT on the collagen area density was noted in the hypertrophic scarring models in rabbit ears.The HMME-SDT could lower the collagen area density,compared with the model group,with significant difference from the fourth week of the epithelialization (P＜0.01).Conclusions HMME is an effective sonosensitizer.HMME-SDT can significantly inhibit hypertrophic scar of rabbit ear.

Objective:To analyze the clinical characteristics that affect the early outcomes of the elderly patients with transient ischemic attack(TIA) and provide the guidance for the prediction of disease recurrence.Methods:From January 2016 to December 2019, 315 TIA patients over 60 years old based on the time-clinical definition who were admitted to the department of neurology in Beijing Shijitan Hospital were divided into recurrence cerebrovascular events group(RCVEs group) and non-recurrence cerebrovascular events group(non-RCVEs group) according to the recurrence at 1 month after onset. The clinical characteristics of the two groups were compared by Logsitic regression analysis.Results:There were 29 cases in the RCVEs group and 286 cases in the non-RCVEs group. Compared to the non-RCVEs group, patients in RCVEs group were more likely have higher prevalence of hypertension history(14/15, 83/203), moderate or severe intracranial artery stenosis(21/8, 132/154), carotid stenosis(22/7, 107/179), DWI positive, motor symptoms, carotid artery stenting and higher times of TIA episodes(2(2, 3), 2(1, 2)), fasting blood glucose and glycosylated hemoglobin levels(8.86(8.17, 9.56)mmol/L, 5.82(5.27, 6.33)mmol/L). Logistic regression analysis showed that patients in RCVEs group had a DWI positive( B=1.634, OR=5.124, 95% CI: 2.898-9.059, P=0.000) and higher prevalence of moderate to severe stenosis of carotid artery( B=0.572, OR=1.773, 95% CI: 1.050-2.993, P=0.032). Conclusion:DWI positive and moderate to severe carotid stenosis may influence the early poor prognosis in patients with TIA.

Objective:To compare the long-term prognosis between open versus closed reduction and internal fixation in the treatment of unstable pelvic fractures.Methods:The data of 402 consecutive patients with unstable pelvic fracture were retrospectively analyzed who had been treated at The First Medical Center and The Fourth Medical Center, PLA General Hospital, and Strategic Support Force Specialty Medical Center from March 2011 to March 2017. This cohort was divided into 2 groups according to the reduction methods. In the open group of 194 cases subjected to open reduction and internal fixation, there were 133 males and 61 females with a median age of 43.0 (30.7, 51.0) years, and 35 cases of type B and 159 cases of type C by the Tile classification. In the closed group of 208 cases subjected to closed reduction and internal fixation, there were 115 males and 93 females with a median age of 45.5 (32.0, 56.0) years, and 40 cases of type B and 168 cases of type C by the Tile classification. The 2 groups were compared in terms of 12-items Short Form Health Survey (SF-12) scores [physical component summary (PCS) and mental component summary (MCS)] at the last follow-up, time from injury to operation, frequency of intraoperative X-ray fluoroscopy, intraoperative and postoperative blood transfusion, operation time, and quality of postoperative fracture reduction.Results:There was no statistically significant difference between the 2 groups in the preoperative general data except for the gender, showing the 2 groups were comparable ( P>0.05). This cohort of 402 patients was followed up for 7.8(6.2, 8.8) years. At the last follow-up, the PCS [49.9 (45.4, 55.4) points] and MCS [53.1 (46.4, 57.6) points] in the closed group were significantly higher than those in the open group [48.2 (41.4, 52.7) and 46.5 (40.6, 53.6) points] ( P<0.05). The closed group incurred significantly shorter time from injury to operation [6 (5, 8) d] and operation time [180 (126, 260) min] than the open group [9 (6, 13) d and 240 (165, 334) min], significantly less intraoperative and postoperative blood transfusion [1.5 (0, 4.0) U] than the open group [5.0 (2.9, 8.0) U], significantly higher frequency of intraoperative X-ray fluoroscopy [104.5 (85.0, 132.0) times] than the open group [21.0 (18.0, 26.0) times], and a significantly higher excellent and good rate of postoperative fracture reduction (92.8%, 193/208) than the open group (86.6%, 168/194) (all P<0.05). Conclusion:In the treatment of patients with unstable pelvic fractures, compared with open reduction and internal fixation, closed reduction and internal fixation can not only significantly shorten the waiting time and operation time of patients, reduce the transfusion during operation, but also achieve better fracture reduction to ultimately improve the quality of life of patients.

Objective To observe the effect of a pulsed electromagnetic field (PEMF) on the bone structure and metabolism of rats with disuse osteoporosis (DOP).Methods One hundred 4-month-old female Sprague-Dawley rats were randomly divided into a control group (INT group),an osteoporosis model group (DOP group),a sodium alendronate group (ALN group) and a pulsed electromagnetic field group (PEMF group),each of 25.The right hind-limbs of the rats in the DOP,ALN and PEMF groups were immobilized by tibia-tail fixation for two weeks to establish a DOP model.The rats in the ALN group were given 1 mg/kg of sodium alendronate once a day,while those in the PEMF group received PEMF at 3.82 mT and 10 Hz with a pulse time of 8 ms for 40 min/d.Five rats in each group were sacrificed at the 2nd,4th,8th and 12th week and their right hind-limbs were separated to measure the bone mineral density (BMD),structural mechanics indexes (the maximum load,maximum displacement and rupture energy) and material mechanics indexes (maximum stress,maximum strain and modulus).Moreover,the expression of tumor necrosis factor alpha (TNF-α) and bone morphogenetic protein 2 (BMP-2) were detected using immunohistochemical methods.Results The average BMD of the model group was significantly lower than that of the ALN group after 2 weeks,and lower than that of the PEMF group after 4 and 8 weeks.After 12 weeks the average BMD of the PEMF group was significantly higher than that of the ALN and model groups.After two and four weeks,all the structural and material mechanics measurements had decreased significantly compared with those of the control group.The average maximum displacement and load of the ALN group had increased significantly compared with the model group after 4 weeks of treatment.After 8 weeks the average maximum load,maximum displacement,rupture energy and maximum stress of the ALN and PEMF groups had increased significantly compared with the model group.Compared with the model group,the average level of TNF-α decreased gradually in both the ALN and PEMF groups from the 2nd week on,while that of BMP-2 increased from the same time point.However,at the 8th week the expression of BMP-2 protein in the PEMF group was on average significantly higher than in the ALN group.Conclusion Both PEMF and sodium alendronate can increase bone density,but PEMF has more persistent effects.

Non-arterial Inflammatory ischemic optic neuropathy(NAION)is a common ocular disease in middle and old ages.Symptoms of optic nerve dysfunction in NAION are caused by cerebral ischemia,which leads to optic atrophy.Recent studies have focused on the early interventions targeting NAION′s risk factors to protect the optic nerve and retinal ganglion cells.This article reviews recent progress in studies on the etiology and risk factors of NAION and potential therapies that may help to preserve optic nerve function in NAION.

For patients with dento-maxillofacial deformities who receive orthodontic-orthognathic combined treatment, the conventional treatment approach is preoperative orthodontic-orthognathic surgery-postoperative orthodontics. However, with the development of techniques used in orthodontic and orthognathic treatment, the surgery-first approach (SFA), namely, orthodontic surgery-postoperative orthodontics, has been widely used currently and displays several advantages, such as improving the treatment efficiency and providing patients with more satisfaction. This review provides a brief discussion and review of SFA concerning its development, indications, advantages and disadvantages, outcomes and stability, and the application and research progress of SFA in orthodontic-orthognathic combined treatment for patients with maxillofacial deformity. The literature review results showed that compared with the conventional treatment approach, SFA has relatively strict indications, which usually include patients with skeletal class Ⅱ/Ⅲ malocclusion, skeletal open bite, and bimaxillary protrusion or patients with facial asymmetry but who require little preoperative orthodontic treatment or removal of the compensation of the dental arch, specifically as follows: ①well-aligned to mildly crowded anterior teeth, ②flat to mild curve of Spee, ③normal to mildly proclined/retroclined incisor inclination, ④acceptable arch coordination, ⑤extensive occlusal contact between the upper and lower dentition requiring at least 3 occlusal contacts. Any occlusion that may affect the outcome of surgery or final result of the overall treatment, as well as any disease that may jeopardize the healing process after surgery, is regarded as a contraindication. Furthermore, SFA has potential disadvantages, such as a possible higher incidence of complications, including unstable occlusion and malunion of bones, which still require further research to be confirmed. Most researchers believe that no significant difference occurs between the outcome and stability of the two approaches. However, currently, we still need a sufficient sample size of prospective studies to provide accurate evidence.