Extracellular signal-regulated kinase (ERK) is a kind of serine/threonine protein kinase. As a key downstream protein in RAS-RAF-MEK-ERK signaling pathway, its abnormal activation plays an important role in the development of tumors. Selective ERK1/2 inhibitors can block ERK signaling pathway while overcoming drug resistance caused by upstream target mutation. In this paper, the components of MAPK signaling pathway, the structure and functions of ERK and the role of ERK signaling pathway in tumor development are summarized, and some representative ERK inhibitors in clinical or preclinical studies are emphasized.

ObjectiveTo investigate the detection results of WBC,CRP,ESR and GR% in patients with knee infection after operation. Methods The study was conducted from March 2012 to January 2015. Twenty patients were collected in the study. The values of WBC,CRP,ESR and GR% were compared and analyzed between pre-operation and post-operation of 1,3 and 7 days. Results The values of WBC,CRP,ESR and GR% in the post-operation of 1 day were higher than those in the pre-operation,and there were statistically significances (P < 0.05). The values of ESR in the post-operation of 3 and 7 days were higher than that in the pre-operation, with statistically significances(P < 0.05). However,the values of WBC,CRP and GR% in the post-operation of 3 and 7 days were no statistically significances compared with those in the pre-operation(P > 0.05). Conclusion WBC,CRP,ESR and GR% have good reference value for early diagnosis and treatment,which can be used as screen testing indexes in the early knee infection.

Objective To explore clinical classification and strategies for irreducible femur intertrochateric fractures.Methods A retrospective study was conducted of the 96 patients with irreducible intertrochanteric fracture who had been treated from January 2012 through December 2014 at our department.They were 47 men and 49 women,aged from 48 to 97 years (average,78.5 years).We classified the fractures according to location of fracture line and mechanism of fracture displacement into 5 types:13 cases of type Ⅰ (sagittal irreducible fracture),7 cases of type Ⅱ] (coronal irreducible fracture),72 cases of type Ⅲll (sagittal plus coronal irreducible fracture),zero of type Ⅳ (irreducible fracture involving the lesser trochanter),and 4 cases of type Ⅴ (irreducible fracture involving the greater trochanter).All the patients were managed using different techniques for closed reduction and fixation with proximal femoral nails antirotation Ⅱ.Results Of this series,limited open reduction was eventually conducted in 7.The operation time averaged 40 min;the amount of intraoperative blood loss averaged 200 mL.Fracture reduction was rated as grade Ⅰ in 78 cases and as grade Ⅱ in 18.The follow-up time averaged 16.6 months (from 12 to 24 months).All the fractures got united after an average of 5.8 months (from 3 to 9 months).The function of the affected hip was rated at the final follow-up using Harris scoring system as excellent in 79 cases and as good in 17,with an excellent to good rate of 100％.Refracture happened in one patient due to striking injury,urinary infection occurred in 2 patients and no wound infection was observed.Conclusion According to the classification and reduction strategy proposed by us,satisfactory reduction and fracture fixation can be achieved in management of irreducible intertrochanteric fractures.

Objective:To revise the 2017 classification of irreducible intertrochanteric fractures and summarize reduction techniques of 2021 classification.Methods:A retrospective analysis was conducted of the 17 patients with irreducible intertrochanteric fracture who had been treated at Department of Orthopaedic Surgery, The Ninth People's Hospital of Shanghai, Shanghai Jiaotong University School of Medicine from January 2015 to December 2019. They were 7 males and 10 females, with an age of (73.2 ± 16.1) years. On the basis of 2017 classification, the irreducible intertrochanteric fractures were classified into 2 types in the present 2021 classification. Type Ⅰ were interlocking fractures which were further classified into 3 subtypes: type ⅠA were sagittal interlocking ones (7 cases), type ⅠB greater trochanter interlocking ones (one case) and type ⅠC lesser trochanter interlocking ones (one case). Type Ⅱ were separating fractures which were further classified into 4 subtypes: type ⅡA were sagittal separating ones (4 cases), type ⅡB coronal separating ones (one case), type ⅡC rotational separating ones(one case) and type ⅡD complete separating ones (2 cases). All patients were treated by closed reduction and intramedullary nailing with different reduction strategies corresponding to their fracture types (application of ejector rods, clamps or prying techniques, etc.). A total of 132 patients with reducible femoral intertrochanteric fracture who had been admitted during the same period were selected as the control group. The fracture reduction time, intraoperative blood loss and Harris hip score at the last follow-up were compared between the 2 groups.Results:The 2 groups were comparable because there was no significant difference in their preoperative general data ( P>0.05). Type ⅠA accounted for the highest proportion of irreducible intertrochanteric fractures [41.3% (7/17)], followed by type ⅡA [23.6% (4/17)]. The fracture reduction time [(44.6 ± 6.7) min] in the irreducible group was significantly longer than that in the control group [(39.2 ± 9.6) min] ( P<0.05). There was no significant difference in intraoperative blood loss or Harris hip score at the last follow-up between the 2 groups ( P>0.05). Conclusions:Compared with the "2017 classification" , the "2021 classification" is more concise and easy to remember, and can directly prompt the corresponding proper fracture reduction techniques. The patients with irreducible intertrochanteric fracture using proper reduction techniques can obtain functional recovery similar to that in the patients with reducible intertrochanteric fracture after reduction and fixation.

ObjectiveTo investigate the bactericidal effect of loaded multifunctional povidoneiodine-nanometer selenium （PVP-I@Se） disinfectant on Staphylococcus aureus （SA） and methicillin-resistant Staphylococcus aureus （MRSA）， and to provide an experimental basis for the reduction of surgical site infection （SSI）. MethodsThe control group was the povidone iodine （PVP-I） group with different concentrations of iodine （50， 75， 100， 200 and 400 μg/mL）. The PVP-I@Se group （experimental group） was the PVP-I group further supplemented with 2 μg/mL Selenium nanoparticles （SeNPs）. Then we compared the bactericidal effect of the two groups of disinfectant solutions on SA and MRSA by examining the minimum inhibitory concentration （MIC）， minimum bactericidal concentration （MBC）， the shortest sterilization time at a concentration of 50 μg/mL iodine and the inhibition zone diameters at concentrations of 200 μg/mL and 400 μg/mL iodine. ResultsMIC values of PVP-I against SA and MRSA were both 79.17 μg/mL， and those of PVP-I@Se were 54.17 and 70.83 μg/mL， respectively. MBC values of PVP-I against SA and MRSA were 129.17 and 150.00 μg/mL， respectively， and those of PVP-I@Se were 70.83 and 87.50 μg/mL， respectively. At a concentration of 50 μg/mL iodine， the shortest sterilization time of PVP-I for SA and MRSA was 130 s and 140 s， respectively， and that of PVP-I@Se was 65 s and 75 s， respectively. At a concentration of 200 μg/ml iodine， the inhibition zone diameters of PVP-I for SA and MRSA were 7.67 mm and 8.33 mm， and those of PVP-I@Se were both 9.50 mm. At a concentration of 400 μg/mL iodine， the inhibition zone diameters of PVP-I for SA and MRSA were 9.00 mm and 9.33 mm， and those of PVP-I@Se were 11.67 mm and 12.00 mm， respectively. ConclusionsPVP-I with different concentrations of 50， 75， 100， 200 and 400 μg/mL iodine supplemented with 2 μg/mL SeNPs have better and faster bactericidal effect on SA and MRSA. When combined with SeNPs， PVP-I can enhance the bactericidal activity against SA and MRSA， but with better sensitizing effect on SA than MRSA and higher demand of iodine concentration （400 μg/mL） for sensitizing effect on MRSA. This study provides a theoretical basis for selecting optimal concentration and action time of the disinfectant， thus reducing SSI.

Objective: To evaluate the accuracy of a 3D-printed template used to assist the preparation of tibial tunnel in reconstruction of anterior cruciate ligament (ACL). Methods: Twenty healthy adult cadaveric knees were scanned by computed tomography(CT) and magnetic resonance imaging (MRI). The knees were from 11 males and 9 females who had died at an average age of 36 years (range, from 27 to 68 years) and from 8 left and 12 right sides. Individualized 3D reconstruction models of the knee joint were established based on their imaging data. According to the anatomic footprints of the virtual tibial tunnel, 20 individualized navigation templates were designed and printed by 3D printing. The templates were used to assisst preparation of tibial tunnels in the ACL reconstruction for the 20 cadaveric knees. After operation, CT scanning was conducted again to compare the corresponding postitions between the preoperative virtual tunnel and the postoperative actual tunnel. The positions of the tibial tunnel were described by the Tsukada method. Results: The ratio of the distance between the tunnel outlet center and the medial edge of the tibia to the distance between the median and lateral edges of the tibial plateau was 49.7%±2.1% for the preoperative virtual tibial tunnel and 48.8%±2.8% for the postoperative actural tunnel, showing no significant difference between them (t=1.971, P=0.063). The ratio of the distance between the tunnel outlet center and the anterior edge of the tibia to the distance between the anerior and posterior edges of the tibial plateau was 41.3%±1.3% for the preoperative virtual tibial tunnel and 40.3%±3.7% for the postoperative actural tunnel, showing no significant difference between them(t=1.494, P=0.152). Conclusion 3D printing can be used to design and manufacture a navigation template which can accurately assist preparation of tibial bone tunnel in ACL reconstruction.