Advances in enzyme immobilization based on hierarchical porous metal-organic frameworks / 生物工程学报

As an excellent hosting matrices for enzyme immobilization, metal-organic framework (MOFs) provides superior physical and chemical protection for biocatalytic reactions. In recent years, the hierarchical porous metal-organic frameworks (HP-MOFs) have shown great potential in enzyme immobilization due to their flexible structural advantages. To date, a variety of HP-MOFs with intrinsic or defective porous have been developed for the immobilization of enzymes. The catalytic activity, stability and reusability of enzyme@HP-MOFs composites are significantly enhanced. This review systematically summarized the strategies for developing enzyme@HP-MOFs composites. In addition, the latest applications of enzyme@HP-MOFs composites in catalytic synthesis, biosensing and biomedicine were described. Moreover, the challenges and opportunities in this field were discussed and envisioned.

ATP regulation strategy and its application in the synthesis of microbial metabolites / 生物工程学报

Cofactor engineering, as a new branch of metabolic engineering, mainly involves ATP/ADP, NADH/NAD⁺, NADPH/NADP⁺ and other cofactors. Cofactor engineering can maximize metabolic flow by directly regulating the concentration and form of the cofactor of key enzymes in cells, and quickly direct carbon flow to target metabolites. ATP, as an important cofactor, is involved in many enzyme-catalyzed reactions in microbial cells, and leads to the restriction of the distribution of metabolic pathways by connecting or linking them into a complex network. Therefore, ATP regulation strategy is expected to be a favorable tool for industrial strain modification, to improve the concentration and production capacity of target metabolites, strengthen microbial tolerance to the environment and promote substrate utilization rate. The present review focuses on the recently used effective ATP regulation strategies and the effects of ATP regulation on cell metabolism in order to provide references for the efficient construction of microbial cell factories.

Biplane osteotomy assisted by 3D printing for malunion of tibial plateau fracture of Schatzker type Ⅳ / 中华创伤骨科杂志

Objective:To evaluate the biplane osteotomy assisted by 3D printing for malunion of tibial plateau fracture of Schatzker type Ⅳ.Methods:A retrospective study was conducted of the 19 patients with malunion of tibial plateau fracture of Schatzker type Ⅳ who had been treated at Department of Orthopaedics, Jiaozuo People's Hospital and Department of Foot and Ankle Surgery, Zhengzhou Orthopaedics Hospital from February 2014 to May 2018. They were 11 males and 8 females, aged from 20 to 55 years (average, 37.6 years). The interval from injury to operation ranged from 3 to 8 months. All patients were treated with biplane osteotomy assisted by 3D printing. The tibiofemoral angle, tibial plateau varus angle, posterior tilt angle and Lysholm scores of knee joint were recorded before and after treatment. Postoperative complications were observed.Results:All patients were followed up for 12 to 28 months (average, 18.5 months).The fracture healing time ranged from 12 to 24 weeks (average, 15.5 weeks).At the last follow-up, the patient's tibiofemoral angle was 173.2°±2.0°, tibial plateau varus angle was 85.6°±1.3 °, and posterior tilt angle was 11.9°± 1.1 °, which were higher than the preoperative ones (154.1°±5.0°, 76.0°±1.8°, 18.9 °±1.6°), and the differences were statistically significant ( P<0.05).The Lysholm scores at the last follow-up (89.8 ± 1.2) were significantly higher than the preoperative ones (52.0±4.4) ( P<0.05).One patient had to receive total knee arthroplasty because of difficult walking 6 months after operation. Conclusion:Biplane osteotomy assisted by 3D printing can delay development of traumatic arthritis, relieve pain and restore knee function in the treatment of malunion of tibial plateau fracture of Schatzker type Ⅳ.

Cofactor engineering strategy for enhanced S-adenosylmethionine production in Saccharomyces cerevisiae / 生物工程学报

In order to study the role of cofactor engineering in enhancing the production of S-adenosylmethionine (SAM), we altered the form and concentration of cofactor in Saccharomyces cerevisiae through gene recombination. Effects of cofactor on product synthesis, carbon and energy metabolism were analyzed aiming to provide a theoretical basis for a successful metabolic engineering of SAM producing strains. Because NADPH metabolism in mitochondrion and cytoplasm of S. cerevisiae is relatively independent, the effect of intracellular NADPH availability on the production of SAM was studied in different compartments of S. cerevisiae BY4741. The expression of NADH kinase in mitochondria (POS5 encoded) and cytoplasm (POS5Δ17 encoded) was separately confirmed using a laser scanning confocal microscope. NADPH regulation strategy enhanced SAM production. Compared with the control strain, the intracellular SAM concentration of strain NBYSM-1 was increased by 3.28 times, and the intracellular SAM concentration of strain NBYSM-2 was increased by 1.79 times at 24 h fermentation. In addition, SAM titer and NADPH/NADP⁺ ratio in strain NBYSM-1 were significantly higher than that of strain NBYSM-2. Therefore, NADPH regulation strategy will be a valuable tool for SAM production and could further improve the synthesis of a large range of cofactor-driven chemicals.

双侧髋关节离断截肢患儿综合康复1例报道 / 中国康复理论与实践

@# 目的探讨截肢后残疾人综合康复策略。方法个案分析。9岁女童,因车祸骨盆以下截肢。各学科专家和社会工作者组成康复团队,进行综合康复。结果4个月后,女童装上假肢,恢复清纯女孩的外观形象,学会使用假肢、轮椅或特制的小滑板代步,日常生活能力(ADL)提高,正常上学,成绩优秀;将来准备向残疾运动员方向发展。结论综合康复可以实现残疾人回归社会。