OBJECTIVE: To evaluate the clinical outcomes of reverse total shoulder arthroplasty as a revision procedure for the failed fixation of proximal humeral fractures in the elderly patients. METHODS: A retrospective analysis was performed on 8 patients with failed internal fixation of proximal humeral fractures from May 2014 to March 2020, including 3 males and 5 females, aged from 65 to 75 years old. All 8 patients underwent reverse total shoulder arthroplasty, and the mean time between initial fixation and reverse total shoulder arthroplasty ranged from 8 to 16 months. Range of motion(ROM), University of California at Los Angeles(UCLA) shoulder score, visual analogue scale (VAS), self-rating anxiety scale(SAS), and Constant-Murley score of shoulder function were assessed pre-operatively and at the last follow-up. Complications relating to the surgery were recorded. RESULTS: All 8 patients successfully followed up. The mean follow-up after reverse total shoulder arhroplasty ranged from 16 to 28 months. The range of motion (forward flexion, external rotation, abduction and internal rotation) of the affected shoulder was significantly improved after surgery, and the post-operative VAS, SAS and UCLA scores were also significantly improved. For the Constant-Murley score of shoulder joint function, the total scores and the subscores of pain, daily activities, range of motion and strength test at the last follow-up were all significantly improved. Scapular glenoid notch was observed in patient, which was evaluated as grade 1 on imaging. All the other patients did not develop specific or non-specific complications. CONCLUSION Reverse total shoulder arhroplasty is an appropriate treatment as a revision surgery for failed fixation of proximal humeral fractures. It has shown satisfactory clinical outcomes, accelerating the rehabilitation of shoulder function and improving the quality of life.
Male ; Female ; Humans ; Aged ; Shoulder/surgery* ; Arthroplasty, Replacement, Shoulder/methods* ; Retrospective Studies ; Treatment Outcome ; Quality of Life ; Shoulder Joint/surgery* ; Shoulder Fractures/surgery* ; Humerus/surgery* ; Range of Motion, Articular

Functional membrane microdomains (FMMs) that are mainly composed of scaffold proteins and polyisoprenoids play important roles in diverse cellular physiological processes in bacteria. The aim of this study was to identify the correlation between MK-7 and FMMs and then regulate the MK-7 biosynthesis through FMMs. Firstly, the relationship between FMMs and MK-7 on the cell membrane was determined by fluorescent labeling. Secondly, we demonstrated that MK-7 is a key polyisoprenoid component of FMMs by analyzing the changes in the content of MK-7 on cell membrane and the changes in the membrane order before and after destroying the integrity of FMMs. Subsequently, the subcellular localization of some key enzymes in MK-7 synthesis was explored by visual analysis, and the intracellular free pathway enzymes Fni, IspA, HepT and YuxO were localized to FMMs through FloA to achieve the compartmentalization of MK-7 synthesis pathway. Finally, a high MK-7 production strain BS3AT was successfully obtained. The production of MK-7 reached 300.3 mg/L in shake flask and 464.2 mg/L in 3 L fermenter.
Bacillus subtilis/metabolism* ; Vitamin K 2/metabolism* ; Bioreactors/microbiology* ; Membrane Microdomains/metabolism*

Bacillus subtilis is recognized as a generally-regarded-as-safe strain, and has been widely used in the biosynthesis of high value-added products, including N-acetylneuraminic acid (NeuAc) which is widely used as a nutraceutical and a pharmaceutical intermediate. Biosensors responding to target products are widely used in dynamic regulation and high-throughput screening in metabolic engineering to improve the efficiency of biosynthesis. However, B. subtilis lacks biosensors that can efficiently respond to NeuAc. This study first tested and optimized the transport capacity of NeuAc transporters, and obtained a series of strains with different transport capacities for testing NeuAc-responsive biosensors. Subsequently, the binding site sequence of Bbr_NanR responding to NeuAc was inserted into different sites of the constitutive promoter of B. subtilis, and active hybrid promoters were obtained. Next, by introducing and optimizing the expression of Bbr_NanR in B. subtilis with NeuAc transport capacity, we obtained an NeuAc-responsive biosensor with wide dynamic range and higher activation fold. Among them, P535-N2 can sensitively respond to changes in intracellular NeuAc concentration, with the largest dynamic range (180-20 245) AU/OD. P566-N2 shows a 122-fold of activation, which is 2 times of the reported NeuAc-responsive biosensor in B. subtilis. The NeuAc-responsive biosensor developed in this study can be used to screen enzyme mutants and B. subtilis strains with high NeuAc production efficiency, providing an efficient and sensitive analysis and regulation tool for biosynthesis of NeuAc in B. subtilis.
N-Acetylneuraminic Acid/metabolism* ; Bacillus subtilis/metabolism* ; Promoter Regions, Genetic/genetics* ; Binding Sites ; Biosensing Techniques

Diacylglycerol (DAG) is an intermediate product in lipid metabolism and plays an important physiological role in human body. It is mainly prepared by hydrolyzing lipid with lipase. However, research on the detection method of 1, 2-diacylglycerol (1, 2-DAG) and 1, 3-diacylglycerol (1, 3-DAG) and catalytic specificity of lipase was not enough, which limits its wide application. To address these challenges, an efficient quantitative detection method was first established for 1, 2-DAG (0.025-0.200 g/L) and 1, 3-DAG (0.025-0.150 g/L) by combining supercritical fluid chromatography with evaporative light scattering detector and optimizing the detection and analysis parameters. Based on the molecular docking between Thermomyces lanuginosus lipase (TLL) and triolein, five potential substrate binding sites were selected for site-specific saturation mutation to construct a mutation library for enzyme activity and position specificity screening. The specificity of sn-1, 3 of the I202V mutant was the highest in the library, which was 11.7% higher than the specificity of the wild type TLL. In summary, the position specificity of TLL was modified based on a semi-rational design, and an efficient separation and detection method of DAG isomers was also established, which provided a reference for the study of the catalytic specificity of lipase.
Humans ; Diglycerides ; Molecular Docking Simulation ; Binding Sites ; Catalysis ; Lipase/genetics*

The biofilms formed by pathogenic microorganisms seriously threaten human health and significantly enhance drug resistance, which urgently call for developing drugs specifically targeting on biofilms. Chitooligosaccharides extracted from shrimp and crab shells are natural alkaline oligosaccharides with excellent antibacterial effects. Nevertheless, their inhibition efficacy on biofilms still needs to be improved. Spirulina (SP) is a microalga with negatively charged surface, and its spiral structure facilitates colonization in the depth of the biofilm. Therefore, the complex of Spirulina and chitooligosaccharides may play a synergistic role in killing pathogens in the depth of biofilm. This research first screened chitooligosaccharides with significant bactericidal effects. Subsequently, Spirulina@Chitooligosaccharides (SP@COS complex was prepared by combining chitooligosaccharides with Spirulina through electrostatic adsorption. The binding of the complex was characterized by zeta potential, z-average size, and fluorescence labeling. Ultraviolet-visible spectroscopy (UV-Vis) showed the encapsulation efficiency and the drug loading efficiency reached up to 90% and 16%, respectively. The prepared SP@COS2 exhibited a profound synergistic inhibition effect on bacterial and fungal biofilms, which was mainly achieved by destroying the cell structure of the biofilm. These results demonstrate the potential of Spirulina-chitooligosaccharides complex as a biofilm inhibitor and provide a new idea for addressing the harm of pathogenic microorganisms.
Humans ; Spirulina ; Anti-Bacterial Agents/chemistry* ; Chitosan/pharmacology* ; Biofilms ; Chitin/pharmacology*

Ergothioneine (ERG) is a natural antioxidant that has been widely used in the fields of food, medicine and cosmetics. Compared with traditional plant extraction and chemical synthesis approaches, microbial synthesis of ergothioneine has many advantages, such as the short production cycle and low cost, and thus has attracted intensive attention. In order to engineer an ergothioneine high-yielding Escherichia coli strain, the ergothioneine synthesis gene cluster egtABCDE from Mycobacterium smegmatis and egt1 from Schizosaccharomyces pombe were introduced into E. coli BL21(DE3) to generate a strain E1-A1 harboring the ergothioneine biosynthesis pathway. As a result, (95.58±3.2) mg/L ergothioneine was produced in flask cultures. To further increase ergothioneine yield, the relevant enzymes for biosynthesis of histidine, methionine, and cysteine, the three precursor amino acids of ergothioneine, were overexpressed. Individual overexpression of serA^T410STOP and thrA resulted in an ergothioneine titer of (134.83±4.22) mg/L and (130.26±3.34) mg/L, respectively, while co-overexpression of serA^T410STOP and thrA increased the production of ergothioneine to (144.97±5.40) mg/L. Eventually, by adopting a fed-batch fermentation strategy in 3 L fermenter, the optimized strain E1-A1-thrA-serA^* produced 548.75 mg/L and 710.53 mg/L ergothioneine in glucose inorganic salt medium and rich medium, respectively.
Culture Media ; Ergothioneine/metabolism* ; Escherichia coli/metabolism* ; Fermentation ; Histidine/metabolism* ; Metabolic Engineering

Catechins have been proven to exert antitumor effects in different kinds of cancers. However, the underlying mechanisms have not been completely clarified yet. This study aimed to assess the effects and mechanisms of (-)-epigallocatechin-3-gallate (EGCG) and (-)-epicatechin-3-gallate (ECG) on human melanoma skin A375 cells. Results showed that EGCG and ECG inhibited the proliferation of A375 cells and ECG showed better inhibitory effect. Flow cytometry analysis had shown that EGCG and ECG induced apoptosis and led to cell cycle arrest. EGCG and ECG decreased Bcl-2 expression and upregulated Caspase-3 protein level, indicating the development of apoptosis. Furthermore, EGCG and ECG could decreased mitochondrial membrane potential of A375 cells. In addition, the expression of Beclin-1, LC3 and Sirt3 were downregulated at protein levels, which known to be associated with autophagy. After autophagy was increased by rapamycin, the apoptotic trend was not change, indicating that apoptosis and autophagy are independent. Mechanistically, EGCG and ECG treatments decreased phosphorylated-AMPK (p-AMPK) and increased the ratios of p-PI3K, p-AKT and p-mTOR in melanoma cells. Conclusively, EGCG and ECG induced apoptosis via mitochondrial signaling pathway, downregulated autophagy through modulating the AMPK/mTOR and PI3K/AKT/mTOR signaling pathway. It indicated that EGCG and ECG may be utilized in human melanoma treatment.
AMP-Activated Protein Kinases/genetics* ; Apoptosis ; Autophagy ; Catechin/analogs & derivatives* ; Electrocardiography ; Humans ; Melanoma/drug therapy* ; Phosphatidylinositol 3-Kinases/metabolism* ; Proto-Oncogene Proteins c-akt/metabolism* ; TOR Serine-Threonine Kinases/metabolism*

Aim To study the effect of different hepa- ry.Methods First, heparin derivatives with different rin sulfation patterns on bleomycin induced lung inju- sulfation patterns,6-desulfated heparin (6-DeH) and N-acetvlated heparin ( N-AcH ) , were synthesized.Secondly, the effect of these compounds on BLM-in¬duced bronchial epithelial cell ( BEARS-2B) injury was evaluated via lactate dehydrogenase activity, MTT experiment, Annexin V/ PI staining and Hoechst 33258 staining.Then , immunofluorescence staining and West¬ern blotting were used to investigate the shedding of Svndecan-1 and the activation of c-Met by 6-DeH/Akt j j signaling pathway.Finally, a BLM-induced lung injury mouse model was used to further verify the protective effect of 6-DeH by HE staining, Svndecan-1 immunos- taining,bodv weight change,and survival rate.Results In the BLM-induced BEARS-2B injury model, 6- DeH was selected as the best candidate, which exerted their effect by competitively binding to BLM, thereby reducing the damage of heparan sulfate barrier (Svnde- can-1 ) on cell surface, and improving cell survival by activating the downstream c-Met/Akt pathway.In the BLM-induced lung injury mouse model, it was further confirmed that 6-DeH reduced the shedding of Svnde- can-1 in the early stage, and delayed the lung injury and fibrosis process.Conclusions 6-DeH protects the bronchial epithelial cells against BLM-induced lung in¬jur)' through inhibiting the shedding of Svndecan-1 and activating the c-Met/Akt signaling pathway.

Objective:To describe the clinical features and analyze the prognostic factors of blastemaltype Wilms tumor. To explore the clinical risk factors affecting the prognosis of blastoma.Methods:Clinical data of 75 patients admitted to the surgery department of Beijing Children's Hospital from January 2008 to June 2020 who were confirmed to be blastemal-type Wilms tumor by postoperative pathology without preoperative chemotherapy. The patients' general information, clinical characteristics, inspection data, surgical methods and follow-up results were collected. The related factors which influences its prognosis were analyzed. Among the 75 patients, 45 cases (60.0%) were male and 30 cases (40.0%) were female. The diagnosis age was 6-144 m, mean age was 39.1 m. Left side: 38 cases (50.7%), right side: 37 cases (49.3%). The clinical manifestations were abdominal mass in 35 cases (46.7%), hematuria in 24 cases (32.0%), abdominal pain in 7 cases (9.3%) and physical examination in 9 cases (12.0%). There were Stage Ⅰ 30 cases, Stage Ⅱ 28 cases, Stage Ⅲ 15 cases, Stage Ⅳ 2 cases. There were preoperative tumor rupture in 5 cases, intraoperative tumor rupture in 2 cases. Clinical stage Ⅰ and Ⅱ were classified as early, while stage Ⅲ, Ⅳ were classified as late. According to COG protocol, stage Ⅰ and Ⅱ patients received EE4A, stage Ⅲ and Ⅳ patients received DD4A protocol and radiotherapy. The number of lymph nodes sampled during operation was more than 7 in 10 patients.Results:7 cases were tested for 1p16q. One case(stage Ⅱ) was absent at 1p/16q LOH, and chemotherapy was upgraded from EE4A to DD4A. After the recurrence of 1 case in clinical stage Ⅰ, the 1p/16q heterozygotic deletion test was performed, which was changed to M regimen chemotherapy. Only 1p lost in one case, and 1p/16q was negative in 4 cases, so the original chemotherapy regimen was maintained. A total of 67 patients were recruited to the study. The median follow-up time was 57 months. The 5-year relapse-free survival(RFS) rate was74.7%, and the 5-year overall survival(OS) rate was 88.0%. Cox multivariate regression analysis showed that: advanced clinical stage ( HR=4.9, 95% CI 1.2-19.6, P=0.025), tumor volume ( HR=1.7, 95% CI 0.4-6.9, P=0.048), and tumor rupture ( HR=20.1, 95% CI 4.7-85.5, P<0.001) were independent risk factors for prognosis of blastoma. Gender, age, side profile, clinical manifestations, tumor embolism, and number of lymph nodes sampled had no significant influence on the survival rate of blastoma ( P>0.05). Conclusion:Advanced stage (Ⅲ-Ⅳ), tumor volume≥1 000 ml, tumor weight and tumor rupture were independent risk factors for relapse. Insufficient lymph node sampling and incomplete 1p16q, may be the reasons for the increased risk of local recurrence in low-stage patients due to the underestimated risk classification and insufficient treatment intensity.