As a biocatalyst, laccase has been widely studied and applied in the papermaking industry. However, the low catalytic efficiency and poor stability of natural laccase limit its application in the pulping process. To develop the laccase with high activity and strong tolerance, we carried out directed evolution for modification of the laccase derived from Bacillus pumilus and screened out the mutants F282L/F306L and Q275P from the random mutant library by high-throughput screening. The specific activities of F282L/F306L and Q275P were 280.87 U/mg and 453.94 U/mg, respectively, which were 1.42 times and 2.30 times that of the wild-type laccase. Q275P demonstrated significantly improved thermal stability, with the relative activity 20% higher than that of the wild-type laccase after incubation at 40 ℃, 50 ℃, and 70 ℃ for 4 h. F282L/F306L and Q275P showed greater tolerance to metal ions and organic solvents than the wild-type laccase. The K_m value of the wild-type laccase was 374.97 μmo/L, and those of F282L/F306L and Q275P were reduced to 318.96 μmo/L and 360.71 μmo/L, respectively, which suggested that the substrate affinity of laccase was improved after mutation. The k_cat values of F282L/F306L and Q275P for the substrate ABTS were 574.00 s^-1 and 898.03 s^-1, respectively, which were 1.1 times and 1.7 times that of the wild-type laccase, indicating the improved catalytic efficiency. Q275P demonstrated better performance than the wild-type laccase in pulping, as manifested by the reduction of 0.82 in the Kappa number and the increases of 2.00% ISO, 7.8%, and 7.2% in whiteness, tensile index, and breaking length, respectively. This work lays a foundation for improving the adaptation of laccase to the environment of the papermaking industry.
Laccase/chemistry* ; Directed Molecular Evolution ; Enzyme Stability ; Bacillus pumilus/genetics* ; Mutation ; Biocatalysis ; Catalysis

Objective To investigate the effect of esketamine on astrocyte activation in the spinal dorsal horn of mice with chronic pain and evaluate its impact on Wnt/β-catenin signaling.Methods Forty C57BL/6J mice were randomly divided into five groups:sham surgery(sham)group,pain model(model)group,low-dose esketamine(L-Es)group,medium-dose esketamine(M-Es)group,and high-dose esketamine(H-Es)group.Except in the sham group,chronic pain was induced via sciatic nerve branch selective injury.Each group received the designated treatment.Mechanical withdrawal threshold(MWT)and thermal withdrawal latency(TWL)were measured.Spinal cord expression of glial fibrillary acidic protein(GFAP)was evaluated by immunohistochemistry.Immunofluorescence was used to assess astrocyte activation in the dorsal horn.Enzyme-linked immunosorbent assays measured levels of interleukin-1β(IL-1β),interleukin-6(IL-6),and tumor necrosis factor-α(TNF-α)in the spinal cord.Quantitative reverse transcription polymerase chain reaction(qRT-PCR)was performed to analyze mRNA expression patterns of Wnt3a,β-catenin,and Cyclin D1.Protein expression levels of Wnt3a,β-catenin,and Cyclin D1 in the spinal cord were evaluated by Western Blot.Results Compared with the sham group,mice in the model group showed significantly reduced MWT and TWL(both P＜0.001).Levels of interleukin-1β,interleukin-6,and TNF-α,as well as expression of GFAP protein,were substantially increased(all P＜0.001);co-expression was evident between GFAP and Iba-1.mRNA and protein expression levels of Wnt3a,β-catenin,and Cyclin D1 were also significantly elevated(all P＜0.001).Compared with the model group,mice in all esketamine dose groups exhibited significantly increased MWT and TWL,and there was a dose-dependent effect(all P＜0.001).Levels of IL-1β,IL-6,TNF-α,and GFAP protein expression were significantly reduced(P＜0.05),co-expression of GFAP and Iba-1 was absent,and the mRNA and protein expression levels of Wnt3a,β-catenin,and Cyclin D1 were significantly decreased(P＜0.001).Conclusions Esketamine inhibits astrocyte activation and the inflammatory response,reducing chronic pain.The mechanism may involve regulation of Wnt/β-catenin signaling.

Objective To investigate the effect of esketamine on astrocyte activation in the spinal dorsal horn of mice with chronic pain and evaluate its impact on Wnt/β-catenin signaling.Methods Forty C57BL/6J mice were randomly divided into five groups:sham surgery(sham)group,pain model(model)group,low-dose esketamine(L-Es)group,medium-dose esketamine(M-Es)group,and high-dose esketamine(H-Es)group.Except in the sham group,chronic pain was induced via sciatic nerve branch selective injury.Each group received the designated treatment.Mechanical withdrawal threshold(MWT)and thermal withdrawal latency(TWL)were measured.Spinal cord expression of glial fibrillary acidic protein(GFAP)was evaluated by immunohistochemistry.Immunofluorescence was used to assess astrocyte activation in the dorsal horn.Enzyme-linked immunosorbent assays measured levels of interleukin-1β(IL-1β),interleukin-6(IL-6),and tumor necrosis factor-α(TNF-α)in the spinal cord.Quantitative reverse transcription polymerase chain reaction(qRT-PCR)was performed to analyze mRNA expression patterns of Wnt3a,β-catenin,and Cyclin D1.Protein expression levels of Wnt3a,β-catenin,and Cyclin D1 in the spinal cord were evaluated by Western Blot.Results Compared with the sham group,mice in the model group showed significantly reduced MWT and TWL(both P＜0.001).Levels of interleukin-1β,interleukin-6,and TNF-α,as well as expression of GFAP protein,were substantially increased(all P＜0.001);co-expression was evident between GFAP and Iba-1.mRNA and protein expression levels of Wnt3a,β-catenin,and Cyclin D1 were also significantly elevated(all P＜0.001).Compared with the model group,mice in all esketamine dose groups exhibited significantly increased MWT and TWL,and there was a dose-dependent effect(all P＜0.001).Levels of IL-1β,IL-6,TNF-α,and GFAP protein expression were significantly reduced(P＜0.05),co-expression of GFAP and Iba-1 was absent,and the mRNA and protein expression levels of Wnt3a,β-catenin,and Cyclin D1 were significantly decreased(P＜0.001).Conclusions Esketamine inhibits astrocyte activation and the inflammatory response,reducing chronic pain.The mechanism may involve regulation of Wnt/β-catenin signaling.

Objective:To construct an evaluation index system of operation quality and effectiveness of compact urban medical groups and provide references for evaluation of compact urban medical groups.Methods:The evaluation index system was constructed by Delphi method,and the weight was determined by analytic hierarchy process.Results:The evaluation index system consisted of 5 primary indexes,12 secondary indexes and 40 tertiary indexes.Providing assessment methods for the construction of medical groups,the evaluation index system is scientific and authoritative.Conclusion:At the initial stage,policy support should be strengthened,innovative governance mechanisms should be explored,and measures such as implementing a community of responsibilities,strengthening information interconnection,and improving profit distribution mechanisms should be taken to gradually promote the construction of close urban medical groups.

As the main force in the field of medical and health care, public hospitals are the main positions for people to have medical treatment. The governance quality and efficiency of public hospitals directly affect people′s medical needs and medical experience. Taking Y Hospital as an example, this paper introduced Y Hospital to deepen the requirements of " three turns" , focused on the main responsibility and main business, consolidated the three-level supervision responsibility of " examinee+ invigilator+ inspection" , explored the multi-department joint supervision mechanism of discipline inspection, audit, finance, and profession, and built a large supervision system of " two vertical, two horizontal and one pivot" that met the actual needs of current public hospitals, promoting the hospital from passively accepting external supervision to proactively strengthening internal supervision. It can provide reference for other public hospitals to strengthen their management and improve the efficiency of governance.

As the main force in the field of medical and health care, public hospitals are the main positions for people to have medical treatment. The governance quality and efficiency of public hospitals directly affect people′s medical needs and medical experience. Taking Y Hospital as an example, this paper introduced Y Hospital to deepen the requirements of " three turns" , focused on the main responsibility and main business, consolidated the three-level supervision responsibility of " examinee+ invigilator+ inspection" , explored the multi-department joint supervision mechanism of discipline inspection, audit, finance, and profession, and built a large supervision system of " two vertical, two horizontal and one pivot" that met the actual needs of current public hospitals, promoting the hospital from passively accepting external supervision to proactively strengthening internal supervision. It can provide reference for other public hospitals to strengthen their management and improve the efficiency of governance.

OBJECTIVE: To investigate the feasibility and effectiveness of absorbable anchor combined with Kirschner wire fixation in the reconstruction of extension function of old mallet finger. METHODS: Between January 2020 and January 2022, 23 cases of old mallet fingers were treated. There were 17 males and 6 females with an average age of 42 years (range, 18-70 years). The cause of injury included sports impact injury in 12 cases, sprain in 9 cases, and previous cut injury in 2 cases. The affected finger included index finger in 4 cases, middle finger in 5 cases, ring finger in 9 cases, and little finger in 5 cases. There were 18 patients of tendinous mallet fingers (Doyle type Ⅰ), 5 patients were only small bone fragments avulsion (Wehbe type ⅠA). The time from injury to operation was 45-120 days, with an average of 67 days. The patients were treated with Kirschner wire to fix the distal interphalangeal joint in a mild back extension position after joint release. The insertion of extensor tendon was reconstructed and fixed with absorbable anchors. After 6 weeks, the Kirschner wire was removed, and the patients started joint flexion and extension training. RESULTS: The postoperative follow-up ranged from 4 to 24 months (mean, 9 months). The wounds healed by first intention without complications such as skin necrosis, wound infection, and nail deformity. The distal interphalangeal joint was not stiff, the joint space was good, and there was no complication such as pain and osteoarthritis. At last follow-up, according to Crawford function evaluation standard, 12 cases were excellent, 9 cases were good, 2 cases were fair, and the good and excellent rate was 91.3%. CONCLUSION Absorbable anchor combined with Kirschner wire fixation can be used to reconstruct the extension function of old mallet finger, which has the advantages of simple operation and less complications.
Male ; Female ; Humans ; Adult ; Bone Wires ; Fracture Fixation, Internal ; Finger Injuries/surgery* ; Fractures, Bone/surgery* ; Tendon Injuries/surgery* ; Fingers ; Treatment Outcome ; Finger Joint/surgery*

Objective: To evaluate the efficacy of dynamic locking screw combined with plate internal fixation for tibial fractures. Methods: A retrospective case-control study was conducted to analyze the clinical data of 36 patients with tibial fractures (AO 4A-C) admitted to the Second Affiliated Hospital of Army Medical University from March 2017 to March 2018. There were 27 males and nine females, aged 26-71 years [(51.6±14.3)years]. A total of 18 patients were treated with dynamic locking screw combined with locking plate internal fixation (Group A), and another 18 patients received common locking screw combined with locking plate internal fixation (Group B). The operation time, intraoperative bleeding, hospital stay, visual analogue score (VAS), callus growth and fracture healing rate at 4, 8, 12 and 24 weeks after operation were compared between the two groups. At the same time, the complications of internal fixation were evaluated, including screw loosening, screw fracture and steel plate fracture. Results: All the patients were followed up for 8-18 months [(12.2±2.7)months]. There was no significant difference in operation time, intraoperative bleeding, postoperative hospital stay and postoperative VAS between the two groups (P>0.05). At 8 and 12 weeks after operation, the callus growth rate of Group A was 61% and 83% respectively, significantly higher than those of Group B (28% and 50%) (P<0.05). At 8, 12, and 24 weeks after operation, the fracture healing rate of Group A was 17%, 50% and 100% respectively, and those of Group B was 6%, 28% and 89%, showing no significant difference between the two groups (P>0.05). No complications or failure of internal fixation were found during the follow-up. Conclusion For tibial fractures, the locking plate internal fixation can achieve satisfactory clinical outcome, but the dynamic locking screw system can promote the growth of callus at early stage.

Objective To summarize and analyze the results of our university graduates' participation in the national medical licensing examination in order to investigate the clinical medical teaching reform.Methods There were 770 candidates who took the NMLE from 2011 to 2013.Excel 2007 was used to statistically analyze the total score,passing rate,average score and mastery rate for each subject,and average score and mastery rate at different cognitive level.Results In these three years,our candidates' total pass rate was higher than the national average total pass rate,respectively higher 17.11％,18.10％,17.82％;the pass rate of practical skills examination was also higher than the national average pass rate,respectively higher 7.30％ and 7.19％ and 5.90％;the pass rate of theory examination was higher than the national average pass rate,respectively higher 12.91％,12.97％ and 14.29％.The average score and mastery rate for each subject,the average score and mastery rate at different cognitive level were also all higher than those of the national average of medical colleges.Conclusions National medical licensure examination can be used as an important reference,through optimization of medical curriculum and teaching mode,optimization of clinical practice skills training system and optimization of clinical practical skill evaluation system etc.,to further improve the clinical medical personnel training mode.

Objective To summarize the successful experience of three cases of heart-lung transplantations performed in our institute.Methods From July 2003 to August 2012,three patients,with diagnosis of end-stage heart-lung diseases,received heart-lung transplantation in our institute.One case was diagnosed as congenital atrial septal defect,Eisenmanger syndrome,NYHA class Ⅳ; one was dilated cardiomyopathy with moderate/severe pulmonary arterial hypertension,NYHA class Ⅲ-Ⅳ,one was diagnosed as double outlet left ventricle (DOLV) with ventricle septal defect and stenosis of pulmonary artery and its left and right branches,NYHA class Ⅲ-Ⅳ.Donor hearts were preserved with UW solution,donor lungs were preserved with Euro-Collin solution in case one and with low potassium dextran containing prostaglandin E1 in the others.Extensive disinfection and strict scrutiny were implemented postoperatively.Immunosuppressive therapy included administration of zenapax or basiliximab preoperatively,methylprednisolone during the operation,and cyclosporine a/tacrolimus + prednisone + mycophenolate postoperatively.Surgical hemostasis is of great importance,as the total pleural effusion reaches 14 640 ml within 31 days postoperatively in case two.Strict postoperative disinfection and isolation were implemented,and management of the respiratory tract was intensified.Therapeutic bronchoscopy was performed frequently for sputum suction.In case two,bronchoscopy was used thirteen times within 40 days after transplantation.Broad-spectrum antibiotics and antifungal antibiotics were used for infection control.Results All three patients were discharged after recovery from operation.Case one died of obstructive bronchitis and lung failure caused by chronic rejection four years and ten months postoperatively.Case two died of sudden cerebrovascular accident 68 days after operation.Case three survives more than one year postoperatively so far and is still alive.Conclusion Proper preservation of the donor heart and lung,perfect surgical hemostasis,strict infection control,frequent application of bronchoscopy and appropriate immunosuppressive management are critical to the success of heart-lung transplantation.