Objective To study the cyfluthrin resistance and potential mechanisms of Anopheles sinensis in Nanchang Chang-bei International Airport,Nanchang City,Jiangxi Province. Methods The resistance levels of the local An. sinensis were de-tected by WHO drug resistance bioassay. During the bioassay,the dying mosquitos were classed as sensitive mosquitos,and the survival ones were classed as resistant mosquitos. The P450 monooxygenase activity and glutathione S-transferase activity were detected and compared between the two groups. At the same time,the death time of each sensitive mosquito was recorded,and the correlations between the death time and the P450 monooxygenase activity and glutathione S-transferase activity were ana-lyzed,respectively. Results The bioassay mortality of the local An. sinensis was 59.5%. The differences of the P450 monooxy-genase activities among the resistant mosquitos,sensitive mosquitos and laboratory sensitive mosquitos had statistical signifi-cances(F=151.89,P<0.01),the resistant mosquitos>sensitive mosquitos>laboratory sensitive mosquitos. The differences of glutathione s-transferase activities among the three groups had no statistical significance(F=0.72,P=0.49). There existed positive correlation between the mosquito death time and the P450 monooxygenase activity,and the regression equation was y=79.479+1.512x with the correlation coefficient of 0.88,while there was no correlation between the mosquito death time and the glutathione S-transferaseactivity. Conclusion The An. sinensis in Nanchang Changbei International Airport has been resistant to cyfluthrin,and the promotion of P450 monooxygenase activity maybe one of the reasons for the resistance.

Objective To study the feasibility and safety of total en bloc spondylectomy (TES) for bone tumors of the fourth lumbar spine and evaluate the clinical outcomes.Methods From March 2011 to December 2013,21 patients undergone total en bloc spondylectomy in posterior-only approach were retrospectively reviewed.The patients included 9 males and 12 females,with a mean age of 47.1± 15.6 years old (range,15-71 years old).This series included 12 cases of primary bone tumors and 9 cases of solitary metastases.Preoperative evaluation according to clinical,imaging and pathologic features was performed meticulously to select patients.The length of surgery,estimated blood loss,surgical margins,instrumentation failure,perioperative complications,Frankel scale,visual analogue scale (VAS) for pain,local control rate and overall survival were reviewed and analyzed.Results Total en bloc spondylectomy was performed successfully in all patients.Average operative time and estimated blood loss were 297.6±44.6 min (range,225-420 min) and 2 247.1±904.5 ml (range,900-4100 ml),respectively.The mean follow-up time was 50.4± 17.1 mons (range,24-79 mons).All patients encountered nerve roots stretch and 5 patients (23.8％) showed lower extremeties neurological dysfunction.All of them improved in 2-4 weeks postoperatively and recovered completely at 6-month follow -up.Cerebrospinal fluid leak was found in 4 patients (19.0％).The VAS score was 1.5±1.4 at post-operation,which was significantly lower than the 6.2± 1.6 in average at operation (P=0.008).Three patients with metastatic tumors died during the follow-up.Titanium mesh cage subsidence was observed in 7 patients (33.3％).No implant failure was occurred during the follow-up.Conclusion Total en bloc spondylectomy for tumors of the fourth lumbar spine in a posterior-only approach is feasible.However,there are many intraoperative neurological complications and the indications for TES are extremely limited.

Objective:To propose and verify a surgical classification system for the axial primary malignant and aggressive benign tumor.Methods:The CZH surgical classification system was originally developed for the axial primary malignant and aggressive benign tumor. The CZH surgical classification system includes seven types, according to the anatomic features and the extension of tumor violation. A total of 136 patients (79 males and 57 females) with axial primary malignant and aggressive benign tumor from multiple tertiary centers who received surgery from July 2006 to July 2019 were included. The average age was 44.40±17.55 years (8-83 years) old. There were 99 malignant tumors and 37 aggressive benign tumors included. The number of patients with each classification was presented as followed, Type I 13, Type II 15, Type IIIa 3, Type IIIb 20, Type IVa 43, Type IVb 12, Type Va 21, Type Vb 3, Type VI 2, Type VIIa 3 and Type VIIb 1. Surgical procedures were selected according to different types in classification. The inter- and intra-observer consistencies were evaluated by the Kendall's W test. The VAS, Frankel score, overall survival and recurrence free survival were recorded during the follow-up. Results:The inter- and intra-observer consistent coefficient was 0.973 and 0.996, respectively ( P<0.05). The single posterior approach was adopted for the Type II tumors. Other patients underwent surgery by the combined antero-posterior approach. The majority in anterior approach (113 cases) was the modified submandibular approach. The reconstruction modes included anterior "T" shape titanium mesh (112 cases) or the 3D printed prothesis (7 cases) combined with the posterior occipto-cervical fusion (92 cases) or the pedicle screw system (44 cases). The average surgical duration and the volume of intraoperative bleeding was 348.40±136.14 min (60-760 min) and 1 225.69±859.40 ml (80-4 000 ml), respectively. The operation duration and volume of intraoperative bleeding among each type were with statistical difference. The patients with Type IV, V tumors had longer operation duration than those with Type II tumors. Those with Type V and VII tumors had longer operation duration than those with Type I tumors. The patients with Type V tumors had more intraoperative bleeding than those with Type I-IV tumors. The average preoperative VAS score was 4.15±2.25 and then was reduced significantly to 0.62±0.71 and 0.38±0.59 at one and three months after operation, respectively. The Frankel score was also significantly ameliorated at one and three months postoperatively. There were 22 postoperative complications (16.2%). The complications included cerebral spinal fluid leak (12.5%), dysphagia and/or dysphonia (7.4%), dyspnea (5.1%), wound infection (3.7%), wound hemorrhage (2.2%) and pharyngeal dehiscence (1.5%). The incidence of postoperative complication was 25.9% in Type IV-VII tumors, while 11.8% in Type I-III tumors. Conclusion:CZH surgical classification system was verified with high observer consistency. This classification system could assist surgeons to select proper surgical approaches, resection modes and reconstruction modes, and thus ensure the safety of surgery and reduce the recurrence. The tumors in Type IV, V and VII may be with more challenging for surgeons. The incidence of postoperative complication in Type IV-VII tumors may be higher than that in Type I-III tumors.