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1.
Plant J ; 116(6): 1842-1855, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37665679

ABSTRACT

Perennial monocarpic mass flowering represents as a key developmental innovation in flowering time diversity in several biological and economical essential families, such as the woody bamboos and the shrubby Strobilanthes. However, molecular and genetic mechanisms underlying this important biodiversity remain poorly investigated. Here, we generated a full-length transcriptome resource incorporated into the BlueOmics database (http://blueomics.iflora.cn) for two Strobilanthes species, which feature contrasting flowering time behaviors. Using about 112 and 104 Gb Iso-seq reads together with ~185 and ~75 Gb strand-specific RNA seq data, we annotated 80 971 and 79 985 non-redundant full-length transcripts for the perennial polycarpic Strobilanthes tetrasperma and the perennial monocarpic Strobilanthes biocullata, respectively. In S. tetrasperma, we identified 8794 transcripts showing spatiotemporal expression in nine tissues. In leaves and shoot apical meristems at two developmental stages, 977 and 1121 transcripts were differentially accumulated in S. tetrasperma and S. biocullata, respectively. Interestingly, among the 33 transcription factors showing differential expression in S. tetrasperma but without differential expression in S. biocullata, three were involved potentially in the photoperiod and circadian-clock pathway of flowering time regulation (FAR1 RELATED SEQUENCE 12, FRS12; NUCLEAR FACTOR Y A1, NFYA1; PSEUDO-RESPONSE REGULATOR 5, PRR5), hence provides an important clue in deciphering the flowering diversity mechanisms. Our data serve as a key resource for further dissection of molecular and genetic mechanisms underpinning key biological innovations, here, the perennial monocarpic mass flowering.


Subject(s)
Flowers , Transcriptome , Humans , Transcriptome/genetics , Flowers/genetics , Flowers/metabolism , Gene Expression Profiling , Plant Leaves/metabolism , RNA-Seq , Gene Expression Regulation, Plant/genetics
2.
Microb Cell Fact ; 23(1): 154, 2024 May 25.
Article in English | MEDLINE | ID: mdl-38796463

ABSTRACT

Microbial cell factories serve as pivotal platforms for the production of high-value natural products, which tend to accumulate on the cell membrane due to their hydrophobic properties. However, the limited space of the cell membrane presents a bottleneck for the accumulation of these products. To enhance the production of intracellular natural products and alleviate the burden on the cell membrane caused by product accumulation, researchers have implemented various membrane engineering strategies. These strategies involve modifying the membrane components and structures of microbial cell factories to achieve efficient accumulation of target products. This review summarizes recent advances in the application of membrane engineering technologies in microbial cell factories, providing case studies involving Escherichia coli and yeast. Through these strategies, researchers have not only improved the tolerance of cells but also optimized intracellular storage space, significantly enhancing the production efficiency of natural products. This article aims to provide scientific evidence and references for further enhancing the efficiency of similar cell factories.


Subject(s)
Cell Membrane , Escherichia coli , Cell Membrane/metabolism , Escherichia coli/metabolism , Escherichia coli/genetics , Biological Products/metabolism , Metabolic Engineering/methods , Saccharomyces cerevisiae/metabolism
3.
Biochem Cell Biol ; 101(2): 148-159, 2023 04 01.
Article in English | MEDLINE | ID: mdl-36861809

ABSTRACT

Nuclear receptor 4A1 (NR4A1), a member of the NR4A subfamily, acts as a gene regulator in a wide range of signaling pathways and responses to human diseases. Here, we provide a brief overview of the current functions of NR4A1 in human diseases and the factors involved in its function. A deeper understanding of these mechanisms can potentially improve drug development and disease therapy.


Subject(s)
Nuclear Receptor Subfamily 4, Group A, Member 1 , Signal Transduction , Humans , Nuclear Receptor Subfamily 4, Group A, Member 1/metabolism , Nuclear Receptor Subfamily 4, Group A, Member 2/genetics
4.
Bioorg Chem ; 116: 105382, 2021 11.
Article in English | MEDLINE | ID: mdl-34598087

ABSTRACT

The bone morphogenetic protein-2 (BMP-2) is an essential regulator of bone formation and remodeling, which has also been implicated in the pathogenesis of osteoarthritis and its closely related chondrocyte senescence. The BMP-2 uses a conformational wrist epitope and a linear knuckle epitope to interact with type-I (BMPR-I) and type-II (BMPR-II) receptors, respectively. Previously, the knuckle epitope has been intensely studied, but the wrist epitope still remains largely unexplored due to its discontinuous nature. In the present work, the intermolecular interaction of BMP-2 with BMPR-I was investigated systematically at structural, energetic and dynamic levels. Three discrete hotspots that represent the key BMPR-I recognition sites of BMP-2 were identified; they are spatially dispersed over the two monomers of BMP-2 dimer and totally account for 83.5 % binding potency of BMP-2 to BMPR-I (hotspot 1: residues 49-70 in monomer 1; hotspot 2: residues 24-31 in monomer 2; hotspot 3: residues 88-107 in monomer 2). Therefore, we defined the three discrete hotspot sites as the core region of wrist epitope; their contribution to the binding increases in the order: hotspot 2 < hotspot 3 < hotspot 1. We demonstrated that the primary hotspot 1 site has a native U-shaped conformation in the full-length BMP-2 protein context, but it cannot maintain in the native conformation when split from the context to obtain a free hotspot-1 peptide, thus largely impairing its binding potency to BMPR-I. We further employed disulfide-bonded cyclization and head-to-tail cyclization to constrain the peptide conformation, and found that only the former can effectively constrain the peptide into native conformation, thus considerably improving its binding affinity to BMPR-I, whereas the latter totally disorders the native conformation, thus rendering the peptide as a full nonbinder of BMPR-I.


Subject(s)
Bone Morphogenetic Protein 2/antagonists & inhibitors , Chondrocytes/drug effects , Drug Design , Peptides/pharmacology , Bone Morphogenetic Protein 2/metabolism , Chondrocytes/metabolism , Dose-Response Relationship, Drug , Epitopes/drug effects , Humans , Molecular Structure , Osteogenesis/drug effects , Peptides/chemical synthesis , Peptides/chemistry , Structure-Activity Relationship
5.
Angew Chem Int Ed Engl ; 60(23): 12904-12910, 2021 06 01.
Article in English | MEDLINE | ID: mdl-33709491

ABSTRACT

SARS-CoV-2 attaches to its host receptor, angiotensin-converting enzyme 2 (ACE2), via the receptor-binding domain (RBD) of the spike protein. The RBD glycoprotein is a critical target for the development of neutralizing antibodies and vaccines against SARS-CoV-2. However, the high heterogeneity of RBD glycoforms may lead to an incomplete neutralization effect and impact the immunogenic integrity of RBD-based vaccines. Investigating the role of different carbohydrate domains is of paramount importance. Unfortunately, there is no viable method for preparing RBD glycoproteins with structurally defined glycans. Herein we describe a highly efficient and scalable strategy for the preparation of six glycosylated RBDs bearing defined structure glycoforms at T323, N331, and N343. A combination of modern oligosaccharide, peptide synthesis and recombinant protein engineering provides a robust route to decipher carbohydrate structure-function relationships.


Subject(s)
Antibodies, Monoclonal/immunology , SARS-CoV-2/metabolism , Spike Glycoprotein, Coronavirus/immunology , Amino Acid Sequence , Angiotensin-Converting Enzyme 2/chemistry , Angiotensin-Converting Enzyme 2/metabolism , Antigen-Antibody Reactions , Binding Sites , COVID-19/pathology , COVID-19/virology , Glycosylation , Humans , Kinetics , Peptide Library , Peptides/chemical synthesis , Peptides/immunology , Peptides/metabolism , Protein Binding , Protein Engineering , Protein Folding , Protein Structure, Tertiary , SARS-CoV-2/isolation & purification , Spike Glycoprotein, Coronavirus/chemistry , Spike Glycoprotein, Coronavirus/genetics , Spike Glycoprotein, Coronavirus/metabolism , Structure-Activity Relationship
6.
J Shoulder Elbow Surg ; 27(3): 381-386, 2018 Mar.
Article in English | MEDLINE | ID: mdl-29310915

ABSTRACT

HYPOTHESIS: The purpose of this study was to determine the effect of a long duration of elbow stiffness on functional outcomes and complications after arthrolysis. METHODS: Participants included consecutive patients with a long duration of elbow stiffness (≥5 years, n = 23) and control patients matched for age, sex, and initial injury type (n = 46). All patients underwent elbow arthrolysis combined with hinged external fixation between March 2014 and March 2016. At baseline and follow-up, we evaluated elbow motion (flexion, extension, supination, pronation, and range of motion) and patient-reported outcomes, including the Mayo Elbow Performance Score (MEPS) and visual analog scale for pain. Postoperative complications including infection, nerve dysfunction, and instability were recorded. RESULTS: There were no significant differences in preoperative elbow pain, range of motion, or MEPS between groups. Postoperatively, pronation and the MEPS in patients with a long disease duration were inferior to those in control patients (P = .041 and P = .016, respectively). Patients with a long disease duration also had a significantly higher incidence of complications than control patients (P = .002). At final follow-up, 7 patients (30%) in the long disease duration group and 3 patients (7%) in the control group presented with nerve symptoms (P = .022). CONCLUSIONS: A long duration of elbow stiffness may negatively influence functional outcomes and increase the risk of complications after arthrolysis.


Subject(s)
Arthroplasty/adverse effects , Elbow Joint/surgery , Joint Diseases/surgery , Postoperative Complications/physiopathology , Range of Motion, Articular/physiology , Adult , Elbow , Elbow Joint/physiopathology , Female , Follow-Up Studies , Humans , Joint Diseases/physiopathology , Male , Prognosis , Retrospective Studies , Time Factors , Treatment Outcome
7.
Int Orthop ; 42(3): 595-600, 2018 03.
Article in English | MEDLINE | ID: mdl-28988397

ABSTRACT

PURPOSE: The purpose of this study was to compare different grades of elbow stiffness and investigate demographic, injury, and treatment factors potentially associated with the development of severe elbow stiffness. METHODS: We performed a retrospective study involving 169 patients with post-traumatic elbow stiffness between June 2014 and June 2016. Patient demographics, injury, and treatment details were reviewed. Patients were classified into three groups according to the elbow motion. Ordinal regression analyses were performed to examine the independent factors. RESULTS: Patients were classified into: mild (49 patients), moderate (59 patients), and severe (61 patients) groups. Patients with severe stiffness had a significantly worse elbow functional performance. Univariate ordinal regression revealed that severe elbow stiffness was associated with high-energy injury (odds ratio [OR] 4.73), olecranon fracture (OR 1.92), fracture-dislocation (OR 2.28), and open fracture (OR 3.24). Multivariate regression showed that higher-energy injuries were associated with severe stiffness (OR 4.45, p = 0.003). CONCLUSIONS: Elbow stiffness after fracture surgery often results in joint stiffness. Severe stiffness often resulted in more significant functional impairment. Our study suggested that high-energy injuries were associated with the development of severe elbow stiffness.


Subject(s)
Arm Injuries/complications , Elbow Injuries , Fractures, Bone/complications , Joint Diseases/etiology , Adolescent , Adult , Aged , Arm Injuries/surgery , Cross-Sectional Studies , Elbow Joint/pathology , Elbow Joint/surgery , Female , Fractures, Bone/surgery , Humans , Joint Diseases/surgery , Male , Middle Aged , Range of Motion, Articular , Retrospective Studies , Risk Factors , Young Adult
8.
Int Orthop ; 42(3): 609-618, 2018 03.
Article in English | MEDLINE | ID: mdl-29288378

ABSTRACT

PURPOSES: The purpose of this study was to evaluate the results of our protocol that include the restoration of mobility using open release combined with external fixation and stability using ligament repair, to determine the optimal timing of surgery, and to investigate whether resection and replacement of the radial head are associated with different outcomes. METHODS: Twenty-six patients with elbow stiffness after operation of terrible triad injury of the elbow were treated with our protocol. We assessed the optimal timing of the operation by comparing outcomes between the early treatment group and the delayed treatment group. The comparison was performed to investigate whether the results differed between resection and replacement of the radial head. Stability of the elbow, range of motion (ROM), Mayo Elbow Performance Score (MEPS), and complications were assessed for each patient. RESULTS: The mean interval from the initial surgery to the index procedure was 13 months, and the mean follow-up period was 29 months. The MEPS increased from a mean of 65 points to 94 points. Twenty-five of 26 patients achieved stability of the elbow, and all patients achieved functional ROM. There were no significant differences between the two subgroups with respect to ROM and stability of the elbow. CONCLUSION: Our protocol can restore mobility and stability. Resection and replacement of the radial head are both feasible using this protocol. Lastly, the timing of the surgery was not very rigorous, and the surgical delay may be insignificant. LEVEL OF EVIDENCE: Level IV; Case Series; Treatment Study.


Subject(s)
Arm Injuries/surgery , Elbow Joint/surgery , Fractures, Bone/surgery , Orthopedic Procedures/methods , Adult , Elbow Joint/pathology , Female , Humans , Male , Middle Aged , Orthopedic Procedures/adverse effects , Postoperative Complications/epidemiology , Radius/injuries , Radius/surgery , Range of Motion, Articular , Retrospective Studies , Time-to-Treatment , Treatment Outcome , Elbow Injuries
9.
J Shoulder Elbow Surg ; 26(5): 809-814, 2017 May.
Article in English | MEDLINE | ID: mdl-28162879

ABSTRACT

BACKGROUND: Being overweight has become a serious public health concern in China. Higher body mass index has been proven to be associated with poor outcome after orthopedic surgery. The purpose of this study was to examine the effect of being overweight on functional outcomes and complications after open arthrolysis for post-traumatic elbow stiffness. METHODS: We performed a retrospective study including 122 patients with post-traumatic elbow stiffness undergoing arthrolysis, including 84 in the normal weight group and 38 in the overweight group. Demographic data, surgical data, and data on preoperative and postoperative functional performance and complications were obtained. RESULTS: Demographic data and disease characteristics were comparable between the 2 groups at baseline. All patients showed significant improvement after elbow arthrolysis. Postoperatively, the range of motion and Mayo Elbow Performance Score of the normal weight group were significantly better than those of the overweight group. Sixteen patients developed postoperative complications. No significant differences in complication rates between the 2 groups were found. CONCLUSIONS: Most patients showed satisfactory functional outcomes after arthrolysis. The postoperative functional outcomes of the overweight group were inferior to those of the normal weight group to a certain extent. This study underlines the importance of detailed rehabilitation instructions in patients with higher body mass index.


Subject(s)
Body Mass Index , Elbow Joint/surgery , Joint Diseases/surgery , Orthopedic Procedures , Range of Motion, Articular , Adult , Cohort Studies , Female , Humans , Male , Overweight/complications , Retrospective Studies , Tissue Adhesions/surgery
10.
Int Orthop ; 41(8): 1627-1632, 2017 08.
Article in English | MEDLINE | ID: mdl-28083670

ABSTRACT

BACKGROUND: Heterotopic ossification (HO) may lead to complete elbow ankylosis, resulting in severe disability. The prognostic factors that may be valuable in guiding treatment of this condition have not yet been evaluated. The goals of this study were to describe the outcomes of open release for ankylosed elbow caused by HO and to analyse factors associated with clinical outcomes. METHOD: This retrospective study assessed 41 patients with ankylosed elbows treated by open release surgery. We report final clinical outcomes and analyses of the association between outcomes and clinical variables. RESULTS: Mean patient age was 36.4 years; follow-up was 36.1 months. Mean arc of motion increased from 0 to 112° post-operatively, mean pronation from 34 to 52°, supination from a mean of 51 to 76°, and Mean Mayo Elbow Performance Score (MEPS) from 42.8 to 84.2. Eight patients experienced recurrence, two of whom underwent a second operation: one for elbow instability and one for revision surgery. Linear regression analysis demonstrated that initial injury type (p = 0.020), articular surface damage (p = 0.001), coma iduringthe initial injury (p = 0.001) and concomitant radial head replacement (p = 0.029) were independent factors affecting the final MEPS. CONCLUSIONS: Satisfactory outcomes were achieved, indicating that open release is effective for ankylosed elbows. Our findings demonstrated that initial injury type, articular surface damage, coma and radial head replacement are outcome predictors affecting final outcomes.


Subject(s)
Ankylosis/surgery , Elbow Joint/surgery , Ossification, Heterotopic/surgery , Adult , Ankylosis/etiology , Female , Humans , Male , Middle Aged , Ossification, Heterotopic/etiology , Prognosis , Range of Motion, Articular , Retrospective Studies , Risk Factors , Treatment Outcome , Young Adult , Elbow Injuries
11.
Int Urol Nephrol ; 56(8): 2623-2633, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38498274

ABSTRACT

Chronic kidney disease (CKD), including chronic glomerulonephritis, IgA nephropathy and diabetic nephropathy, are common chronic diseases characterized by structural damage and functional decline of the kidneys. The current treatment of CKD is symptom relief. Several studies have reported that the phosphatidylinositol 3 kinases (PI3K)/protein kinase B (Akt) signaling pathway is a pathway closely related to the pathological process of CKD. It can ameliorate kidney damage by inhibiting this signal pathway which is involved with inflammation, oxidative stress, cell apoptosis, epithelial mesenchymal transformation (EMT) and autophagy. This review highlights the role of activating or inhibiting the PI3K/Akt signaling pathway in CKD-induced inflammatory response, apoptosis, autophagy and EMT. We also summarize the latest evidence on treating CKD by targeting the PI3K/Akt pathway, discuss the shortcomings and deficiencies of PI3K/Akt research in the field of CKD, and identify potential challenges in developing these clinical therapeutic CKD strategies, and provide appropriate solutions.


Subject(s)
Phosphatidylinositol 3-Kinases , Proto-Oncogene Proteins c-akt , Renal Insufficiency, Chronic , Signal Transduction , Humans , Renal Insufficiency, Chronic/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Proto-Oncogene Proteins c-akt/physiology , Phosphatidylinositol 3-Kinases/metabolism , Apoptosis , Autophagy/physiology , Epithelial-Mesenchymal Transition , Oxidative Stress
12.
Nefrologia (Engl Ed) ; 44(2): 139-149, 2024.
Article in English | MEDLINE | ID: mdl-38697694

ABSTRACT

Losartan is widely used in the treatment of chronic kidney disease (CKD) and has achieved good clinical efficacy, but its exact mechanism is not clear. We performed high-throughput sequencing (HTS) technology to screen the potential target of losartan in treating CKD. According to the HTS results, we found that the tumor necrosis factor (TNF) signal pathway was enriched. Therefore, we conducted in vivo and in vitro experiments to verify it. We found that TNF signal pathway was activated in both unilateral ureteral obstruction (UUO) rats and human proximal renal tubular epithelial cells (HK-2) treated with transforming growth factor-ß1 (TGF-ß1), while losartan can significantly inhibit TNF signal pathway as well as the expression of fibrosis related genes (such as COL-1, α-SMA and Vimentin). These data suggest that losartan may ameliorate renal fibrosis through modulating the TNF pathway.


Subject(s)
Fibrosis , Losartan , Signal Transduction , Tumor Necrosis Factor-alpha , Losartan/pharmacology , Losartan/therapeutic use , Animals , Signal Transduction/drug effects , Rats , Male , Humans , Ureteral Obstruction/complications , Ureteral Obstruction/drug therapy , Rats, Sprague-Dawley , Kidney/pathology , Kidney/drug effects , Renal Insufficiency, Chronic/drug therapy , Renal Insufficiency, Chronic/etiology
13.
Int Immunopharmacol ; 139: 112705, 2024 Jul 18.
Article in English | MEDLINE | ID: mdl-39029235

ABSTRACT

Fibrosis is not a disease but rather an outcome of the pathological tissue repair response. Many myofibroblasts are activated which lead to the excessive accumulation of extracellular matrix components such as collagen and fibronectin with fibrosis. A variety of organs, including kidney, liver, lung, heart and skin, can undergo fibrosis under the stimulation of exogenous or endogenous pathogenic factors. The orphan nuclear receptor 4 group A1 (NR4A1) and nuclear receptor 4 group A2(NR4A2)are belong to the nuclear receptor subfamily and inhibit the occurrence and development of fibrosis. NR4A1 is an inhibitory factor of TGF-ß signaling transduction. Overexpression of NR4A1 in fibroblasts can reduce TGF-ß induced collagen deposition and fibrosis related gene expression. Here, we summarize the current research progress on the NR4A1/2 and fibrosis, providing reference for the treatment of fibrosis.

14.
Environ Sci Pollut Res Int ; 30(50): 109266-109282, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37759064

ABSTRACT

In recent years, the solid wastes from the coal industry have been widely used as soil amendments. Nevertheless, the impact of utilizing coal slime for copper tailing restoration in terms of plant growth, physicochemical characteristics of the tailing soil, and microbial succession remains uncertain.Herein, the coal slime was employed as a modifier into copper tailings. Their effect on the growth and physiological response of Ryegrass, and the soil physicochemical properties as well as the bacterial community structure were investigated. The results indicated that after a 30-day of restoration, the addition of coal slime at a ratio of 40% enhanced plant growth, with a 21.69% rise in chlorophyll content, and a 62.44% increase in peroxidase activity. The addition of 40% coal slime also increased the content of nutrient elements in copper tailings. Following a 20-day period of restoration, the concentrations of available copper and available zinc in the modified tailings decreased by 39.6% and 48.51%, respectively, with 40% of coal slime added. In the meantime, there was an observed augmentation in the species diversity of the bacterial community in the modified tailings. The alterations in both community structure and function were primarily influenced by variations in pH value, available nitrogen, phosphorus, potassium, and available copper. The addition of 40% coal slime makes the physicochemical properties and microbial community evolution of copper tailings reach a balance point. The utilization of coal slime has the potential to enhance the physicochemical characteristics of tailings and promote the proliferation of microbial communities, hence facilitating the soil evolution of two distinct solid waste materials. Consequently, the application of coal slime in the restoration of heavy metal tailings is a viable approach, offering both cost-effectiveness and efficacy as an enhancer.


Subject(s)
Metals, Heavy , Soil Pollutants , Copper , Soil/chemistry , Coal , Soil Microbiology , Metals, Heavy/analysis , Soil Pollutants/analysis
15.
Sci Prog ; 105(2): 368504221102742, 2022.
Article in English | MEDLINE | ID: mdl-35603887

ABSTRACT

As one of the essential components of the braking system, the high-speed train brake disc is an integral part of ensuring the safety of the train. The main objective of this study is to conduct thermal analysis and reliable life prediction on brake discs. The research was conducted by developing a programmer spectrum of brake discs with high-speed train brake discs. According to the results of numerical analysis and the S-N curve of the material, the temperature distribution on the surface of the brake disc is determined, and the fatigue life of the brake disc is predicted. The comparison with the service life of the brake disc verifies the rationality of the calculation results. In addition, a fatigue damage probability model of brake discs is established based on the theory of fatigue cumulative damage. Through the relationship between the reliability of mechanical parts and the number of load cycles, the reliable life of the brake disc under different working conditions is predicted. This work establishes a method of reliable life analysis for brake discs of high-speed trains based on the load spectrum, which could analyze the life and reliability of brake discs more systematically.


Subject(s)
Fatigue , Humans , Reproducibility of Results
16.
Bioengineered ; 13(5): 13801-13814, 2022 05.
Article in English | MEDLINE | ID: mdl-35707845

ABSTRACT

Bone marrow mesenchymal stem cell (BMSC) chondrogenic differentiation contributes to the treatment of osteoarthritis (OA). Numerous studies have indicated that microRNAs (miRNAs) regulate the pathogenesis and development of multiple disorders, including OA. Nevertheless, the role of miR-20a-5p in OA remains obscure. Forty male C57BL/6 mice were divided into four groups and were surgically induced OA or underwent sham surgery in the presence or absence of miR-20a-5p. Flow cytometry was implemented to detect surface markers of BMSCs. Reverse transcription quantitative polymerase chain reaction revealed the upregulation of miR-20a-5p during BMSC chondrogenic differentiation. Western blotting displayed that miR-20a-5p inhibition decreased protein levels of cartilage matrix markers but enhanced those of catabolic and hypertrophic chondrocyte markers in BMSCs. Alcian blue staining, hematoxylin­eosin staining and micro-CT revealed that miR-20a-5p inhibition restrained chondrogenic differentiation and miR-20a-5p overexpression promoted the repair of damaged cartilage and subchondral bone, respectively. Luciferase reporter assay identified that mitogen activated protein kinase kinase kinase 2 (Map3k2) was a target of miR-20a-5p in BMSCs. Moreover, the expression of miR-20a-5p and Map3k2 was negatively correlated in murine cartilage tissues. Knocking down Map3k2 could rescue the suppressive influence of miR-20a-5p inhibition on chondrogenic differentiation of BMSCs. In conclusion, miR-20a-5p facilitates BMSC chondrogenic differentiation and contributes to cartilage repair in OA by suppressing Map3k2.


Subject(s)
MAP Kinase Kinase Kinase 2 , MicroRNAs , Osteoarthritis , Animals , Cartilage/metabolism , Cartilage/pathology , MAP Kinase Kinase Kinase 2/metabolism , MAP Kinase Kinase Kinases , Male , Mice , Mice, Inbred C57BL , MicroRNAs/genetics , Osteoarthritis/metabolism
17.
Int J Surg ; 99: 106590, 2022 Mar.
Article in English | MEDLINE | ID: mdl-35259520

ABSTRACT

BACKGROUND: Rheumatoid arthritis commonly causes transient limitation of joint motion, but the treatment of persistent stiffness in the rheumatoid elbow has rarely been reported. The purpose of this study was to evaluate the long-term clinical results of surgical treatment of rheumatoid elbow stiffness. METHODS: Surgical treatment, including open arthrolysis with hinged external fixation, total synovectomy, and ulnar nerve release and anteriorization, was performed in 48 elbows in 43 patients with rheumatoid arthritis and early joint destruction. Mobility (flexion-extension and pronation-supination), Mayo Elbow Performance Score (MEPS), visual analog scale (VAS) score, muscle strength, nerve symptoms, postoperative complications, and recurrent synovitis were evaluated 9-11 years (average, 9.88 years) postoperatively. RESULTS: The mobility of the elbow was significantly improved over the preoperative period either in extension, flexion, protonation, supination (P < .001, P < .001, P < .001, P = .002). The mean MEPS was significantly improved from 56.25 points (range, 30-90) to 87.40 points (range, 40-100) (P < .001). The pain was relieved, and the mean VAS score was reduced from 3.56 (range, 0-8) to 1.08 (range, 0-5) points (P < .001). Preoperative ulnar nerve symptoms were observed in 17 patients and relieved in 10 (59%) patients, and the mean Amadio score was raised from 6.9 (range, 3-9) to 7.96 (range, 4-9) points (P < .001). Through surgical treatment and postoperative rehabilitation, the mean grip strength of the patients was significantly improved from an average of 9.01 (range, 3.4-18.5) to 17.56 kg (range, 3.9-40.2) (P < .001). Five elbows developed recurrent synovitis, and one underwent total elbow arthroplasty. Postoperative complications were uncommon and not severe. CONCLUSION: Surgical treatment is a reliable procedure for rheumatoid elbow stiffness and can be effective in improving elbow mobility, function, muscle strength, pain relief, and relief of nerve symptoms.


Subject(s)
Arthritis, Rheumatoid , Elbow Joint , Arthritis, Rheumatoid/surgery , Elbow , Elbow Joint/surgery , Follow-Up Studies , Fracture Fixation , Humans , Range of Motion, Articular/physiology , Retrospective Studies , Treatment Outcome
18.
J Drug Target ; 28(7-8): 802-810, 2020.
Article in English | MEDLINE | ID: mdl-32354236

ABSTRACT

Bone morphogenetic protein-2 (BMP-2) is a key regulator of bone formation, growth and regeneration, which contains a conformational wrist epitope and a linear knuckle epitope that are functionally responsible for the protein by mediating its interaction with type-I and type-II receptors, respectively. Previously, a long (19-mer) knuckle peptide derived from the knuckle epitope region (residues 73-92) has been found to promote osteogenesis and bone repair. Here, we attempt to rationally redesign the knuckle peptide by using bioinformatics and machine learning-guided evolution to obtain structurally simplified, potent osteogenic peptides that are capable of targeting type-II receptor. Complex analysis reveals that only a fraction of the epitope region can directly interact with type-II receptor, which represents a small (12-mer) knuckle-derived peptide (KDP0 peptide). Glycine scanning further identifies three KDP0 anchor residues Ser88, Leu90 and Tyr91 that are fundamentally important in the peptide-receptor binding. Systematic mutation, amino acid combination and uniform design of other nine KDP0 non-anchor residues generate 32 new knuckle-derived peptides (KDP1-KDP32); their binding affinities to recombinant protein of human type-II receptor are determined using fluorescence spectroscopy assay. The resulting affinity values (Kd) are used to train six regression models developed by combination of two machine learning methods and three amino acids descriptors. The best SVM/VHSE predictor is then utilised to guide the genetic evolution of a knuckle-derived peptide population. Eight peptides (KDP33-KDP40) with high affinity scores are selected from the improved population, and their osteogenic activities on bone marrow stromal cells are measured using alkaline phosphatase assay. Consequently, six out of the 8 tested peptides exhibit increased activity relative to KDP0 peptide. The KDP34 (DFQTWSFLYVEN) is found as the most potent peptide with APL activities of 195% and 279% at 0.01 and 0.1 µg/ml, respectively, which shares a similar binding mode with the native knuckle epitope and can form diverse nonbonded interactions of hydrogen bond, hydrophobic contact, cation-π/π-π stacking and salt bridge with type-II receptor.


Subject(s)
Bone Morphogenetic Protein Receptors/metabolism , Machine Learning , Osteogenesis/physiology , Peptides/chemistry , Animals , Crystallization , Epitopes/metabolism , Humans , Mice
19.
Ther Adv Chronic Dis ; 11: 2040622320944779, 2020.
Article in English | MEDLINE | ID: mdl-32821363

ABSTRACT

INTRODUCTION: Synthetic fibrous membranes unveil a promising field in anti-adhesion of tendons. Meanwhile, oriented nanofiber structures have been widely studied and used in the application of biomedical engineering, particularly in repairing and strengthening effects. METHODS: In this study, a bi-layer poly(L-lactic acid) (PLLA) electrospun membrane was fabricated, in which the inner oriented fibrous layer was designed to promote tendon healing while outer random aligned layer was designed to prevent peritendinous adhesion. RESULTS: It was found that fibroblasts were aligned along the oriented fiber of membranes in vitro and in a Leghorn chicken model. In biomechanical tests of repaired tendons, no significant difference was found between oriented fibrous membrane and blank control in maximum tensile strength; both oriented fibrous membranes and random fibrous membranes showed lower work of flexion than blank control, which was consistent with gross assessment. CONCLUSION: It was practicable to promote tendon healing while preventing adhesion via bi-layer PLLA membranes with an inner-oriented-fiber fabricated structure.

20.
Chem Sci ; 10(37): 8694-8700, 2019 Oct 07.
Article in English | MEDLINE | ID: mdl-31803444

ABSTRACT

Proteins with tandem repeats have essential physical or biological roles in cells and have been widely investigated as biomaterials or vaccines. Chemically derived proteins with tandem repeats would be beneficial for research, owing to their accurate structures, possibly with precise modifications, produced by chemical synthesis. Traditional protein synthesis often leads to severe handling loss due to multiple ligations and HPLC purifications. To improve the protein synthesis efficiency, we developed a purification/protection handle consisting of a His6 tag and a photo-labile linker. This handle has great potential to facilitate purification with immobilized metal affinity chromatography techniques and also provides orthogonal protection for N-terminal Cys. The synthesis of the model proteins Muc1 and antifreeze glycoprotein mimics shows that the handle decreases the requirement for HPLC and enables both convergent and sequential assembly of peptide segments.

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