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Fibrosis is the main cause of limited range of motion (ROM) of shoulder in patients with frozen shoulder (FS). Overexpression of Interleukin 6 (IL-6) has been correlated with pathogenesis of FS. However, the underlying mechanism remains largely unexplored. In the current study, we focused on isolating synovial fibroblasts of FS and determining the influence of IL-6 as well as PI3K-Akt signaling pathway on the fibrotic process of synovial fibroblasts in FS by using RNA Sequencing (RNA-seq) and other molecular biology techniques. Synovial fibroblasts of FS express more extra cellular matrix (ECM) than that of control. RNA-seq results and bioinformatic analysis indicate that PI3K-Akt signaling pathway play an important role in the fibrotic process of FS, and IL-6 is the most related gene among those related to this process. The expression levels of IL-6 / IL-6R in FS synovial fibroblasts and IL-6 in culture supernatant were both significantly increased. siRNA interference with the expression of IL-6 attenuates the fibrosis level of FS as well as phosphorylation level of Akt. The findings suggest that synovial fibroblasts are key effector cells of fibrosis of FS. Activation of PI3K-Akt pathway can promote fibrosis of synovial fibroblasts in FS. IL-6 is up-regulated in synovial fibroblasts of FS and promoted the FS fibrosis through PI3K-Akt signaling pathway.

Myogenic differentiation plays an important role in pathophysiological processes including muscle injury and regeneration, as well as muscle atrophy. A novel type of posttranslational modification, crotonylation, has been reported to play a role in stem cell differentiation and disease. However, the role of crotonylation in myogenic differentiation has not been clarified.This study aims to find the role of crotonylation during myogenic differentiation and explore whether it is a potential target in myogenic dysfunction disease.C2C12 cell line and skeletal muscle mesenchymal progenitors of Mus musculus were used for myogenic process study in vitro, while muscle injury model of mice was used for in vivo muscle regeneration study. Mass spectrometry favored in discovery of potential target protein of crotonylation and its specific sites.We confirmed the gradual decrease in total protein crotonylation level during muscle differentiation and found decreased crotonylation of AKT1, which facilitated an increase in AKT1 phosphorylation. Then we verified that crotonylation of AKT1 at specific sites weakened its binding with PDK1 and impaired its phosphorylation. In addition, we found that increased expression of the crotonylation eraser HDAC3 decreased AKT1 crotonylation levels during myogenic differentiation, jointly promoting myogenic differentiation.Our study highlights the important role of decrotonylation of AKT1 in the process of muscle differentiation, where it aids the phosphorylation and activation of AKT1 and promotes myogenic differentiation. This is of great significance for exploring the pathophysiological process of muscle injury repair and sarcopenia.

Summary Mucosal-associated invariant T (MAIT) cells are innate-like unconventional T cells that are abundant in humans and have attracted increasing attention in recent years. Mesenchymal stem cells (MSCs) are crucial regulators of immune cells. However, whether MAIT cells are regulated by MSCs is unclear. Here, we explored the effect of MSCs on MAIT cells and revealed the underlying mechanism. We found that MSCs did not influence the proliferation of MAIT cells but strikingly induced an activated phenotype with an increased expression of CD69, TNF-α, IFN-γ, and granzyme B. Moreover, MSCs activated MAIT cells in a TCR-MR1-independent mechanism through MSC-secreted IL-15. We revealed that MSC-derived IL-15 activated MAIT cells by enhancing autophagy activity, which was abolished by the autophagy inhibitor 3-methyladenine. Based on our findings, MAIT cells are activated by MSCs through IL-15-induced autophagy, which may help elucidate the mechanisms underlying some immune responses and diseases and provide guidance for future research., Highlights • MSCs activate MAIT cells to express higher levels of TNF-α, IFN-γ, and granzyme B • MAIT cells are activated in a TCR-MR1-independent way through MSC-secreted IL-15 • MSC-derived IL-15 activates MAIT cells by enhancing autophagy activity, In this article, Shen Huiyong and colleagues show that MSCs do not influence the proliferation of MAIT cells but strikingly induce an activated phenotype with an increased expression of CD69, TNF-α, IFN-γ, and granzyme B. Mechanistically, MSC-derived IL-15 enhances the autophagy level of MAIT cells and results in MAIT cell activation.

To introduce an all-inside modified Broström technique to suture the anterior talofibular ligament (ATFL) and inferior extensor retinaculum (IER) under arthroscopy and to compare its outcomes with those of the conventional open procedure.All patients who underwent arthroscopic or open repair of the ATFL between June 2014 and December 2017 were included in this study. Visual analog scale (VAS), Karlsson and Peterson (K-P), American Orthopedic Foot and Ankle Society (AOFAS) ankle/hindfoot, and Tegner activity scores, as well as manual anterior drawer test (ADT), were used to evaluate the patients preoperatively and ≥2 years after surgery. The Sefton grading system was used to assess the level of satisfaction after surgery. Detailed surgical data and intraoperative findings were documented at the time of surgery.A total of 67 patients, 31 in the arthroscopic group and 36 in the open group, were included in this study (43 men and 24 women, mean body mass index 24.00, range 19.53 to 30.03). The surgical duration in the arthroscopic group (median, 34 minutes; range, 25 to 74) was significantly shorter than that in the open group (mean, 43.08 ± 8.11 minutes; 95% confidence interval [CI] 40.34 to 45.83) (P = .007). At the last follow-up, the subjective functional scores and ADT results improved significantly in both cohorts (P.001). However, no significant difference was found in the VAS score (1.74 ± 1.24, 95% CI 1.29 to 2.2, in the open group versus 1.58 ± 1.2, 95% CI 1.18 to 1.99, in the arthroscopic group; P = .581), AOFAS score (91.71 ± 5.46, 95% CI 89.71 to 93.71, versus 90.67 ± 5.59, 95% CI 88.78 to 92.56; P = .444), K-P score (87.52 ± 7.59, 95% CI 84.73 to 90.3, versus 88.75 ± 5.56, 95% CI 86.87 to 90.63; P = .446), and ADT evaluation (normal: 96.77% versus 94.44%, P = .557) between the arthroscopic and open groups, respectively. In addition, 28 cases (90.32%) in the arthroscopic group and 32 (88.89%) in the open group achieved satisfactory results based on the Sefton grading system (P = .736). Seventeen patients (47.2%) in the open group and 18 patients (58.1%) in the arthroscopic group underwent Tegner evaluation after surgery, which showed no significant difference (5, interquartile range [IQR] 1 in the open group versus 5, IQR 3 in the arthroscopic group; P = .883). Complications were reported in 4 (11.1%) and 2 (6.5%) patients who underwent open and arthroscopic surgeries, respectively (P = .813).Both open and arthroscopic modified Broström surgeries generated favorable outcomes, with a significant improvement compared with the preoperative condition. Compared with the open Broström-Gould procedure, the all-inside arthroscopic modified Broström technique produced equivalent functional and clinical results at a minimum of 2 years after the operation, with a shorter surgical duration. Arthroscopic repair might be a safe and viable alternative to open surgery for lateral ankle stabilization.III.

Background: Although angiogenesis-osteogenesis coupling is important in ankylosing spondylitis (AS), therapeutic agents targeting the vasculature remain elusive. Here, we identified activating transcription factor 6 (ATF6) as an important regulator of angiogenesis. Methods: ATF6 and fibroblast growth factor 2 (FGF2) levels were quantified in SKG mice and AS patient cartilage by immunohistochemistry. Next, we isolated and cultured human chondrocytes and stimulated them with TNF-α, IFN-γ, and IL-17. ATF6 and FGF2 expression was measured by quantitative real-time PCR and western blotting. The angiogenic ability of chondrocytes was assessed with human umbilical vein endothelial cell tube formation and transwell migration assays. Theendoplasmic reticulum stress alleviator 4-phenyl butyric acid and the ATF6 inhibitor Ceapin-A7 were used to indicate the relationship between ATF6 and FGF2. We also performed luciferase reporter and chromatin immunoprecipitation assays to test whether ATF6 was directly responsible for FGF2 transcription, treated SKG mice with Ceapin-A7 to evaluate the role of ATF6 in AS and performed micro-CT and immunofluorescence analyses. Findings: ATF6 and FGF2 expression was elevated in AS cartilage following long-term stimulation with inflammatory factors. Among the three pathways involved in the unfolded protein response, the ATF6 pathway was activated mostly in chondrocytes stimulated long-term with proinflammatory cytokines. In chondrocytes, ATF6 knockdown decreased FGF2 expression and inhibited angiogenesis, whereas ATF6 overexpression had the opposite effects. Mechanistically, ATF6 interacted with the FGF2 promotor and promoted its transcription. Treatment with the ATF6 inhibitor Ceapin-A7 inhibited angiogenesis in vitro and angiogenesis-osteogenesis coupling in vivo. Interpretation: ATF6 may aggravate angiogenesis-osteogenesis coupling during AS by mediating FGF2 transcription in chondrocytes, implying that ATF6 represents a promising therapeutic target for AS. Funding Statement: This study was financially supported by grants from the National Natural Science Foundation of China (81971518), the National Natural Science Foundation of China (81871750), the Natural Science Foundation of Guangdong Province (2018A030313232), the Shenzhen Key Medical Discipline Construction Fund (ZDSYS20190902092851024) and the Health Welfare Fund Project of Futian District (FTWS2020078) Declaration of Interests: All authors declare no conflict of interest. Ethics Approval Statement: This study was approved by the Ethics Committee of The Eighth Affiliated Hospital, Sun Yat-sen University, Shenzhen, China. Written informed consent was obtained from all participants.

DEP domain containing 1 (DEPDC1) is recently reported to be overexpressed in several types of human cancer; however the role of DEPDC1 in prostate cancer remains to be investigated. Herein, we identified that the DEPDC1 mRNA and protein expression levels were dramatically increased in prostate cancer tissues and cell lines. Overexpression of DEPDC1 promoted, but depletion of DEPDC1 inhibited cell proliferation by regulating the G1-S phase cell cycle transition. Importantly, we found that DEPDC1 was essential for the tumor growth and formation of bone metastases of prostate cancer cells in vivo. Finally, we demonstrated that DEPDC1 interacted with E2F1 and increased its transcriptional activity, leading to hyper-activation of E2F signaling in prostate cancer cells. Our findings reveal an oncogenic role of DEPDC1 in prostate cancer progression via activation of E2F signaling, and suggest DEPDC1 might be a potential therapeutic target against the disease.

Background: Although emerging evidence suggests that abnormal angiogenesis is a clinical symptom of ankylosing spondylitis (AS) and might be used as a diagnostic marker to predict disease progression, the cause of ectopic angiogenesis in AS patients is yet unexplored. Methods: Abnormal angiogenesis in AS patients was assessed by anti-CD31 immunohistochemistry. After culturing with mesenchymal stem cells from AS patients (ASMSCs) or healthy donors (HDMSCs), the human umbilical vein endothelial cells (HUVECs) were assayed using a Cell Counting Kit-8 (CCK-8) to evaluate cell proliferation, and a wound healing assay was used to investigate cell migration. In addition, a tube formation assay was used to determine angiogenesis efficiency. RT-qPCR and western blotting were used to quantify the expression of SMAD-specific E3 ubiquitin protein ligase 2 (Smurf2). Proteome profilers were used to identify differential regulatory factors between ASMSCs and HDMSCs. Co-immunoprecipitation, immunofluorescence and mass spectrometry analyses were performed to investigate Smurf2/PTX3 interactions. Dual-luciferase reporter assays and chromatin immunoprecipitation were used to identify the ATF4-specific binding site of the Smurf2 promoter for the activation of transcription. Findings: Compared to HDMSCs, which abnormally promote endothelial cell angiogenesis, we found that the elevated Smurf2 in MSCs is the major cause of abnormal angiogenesis in AS patients. Downregulation of Smurf2 in ASMSCs precludes angiogenesis, whereas overexpression of Smurf2 in HDMSCs promotesangiogenesis. By acting as an E3 ubiquitin ligase, Smurf2 can regulate the abundance of PTX3, which has been shown to be an angiogenesis repressor, in MSCs. Moreover, the Smurf2 transcription is regulated by ATF4 induced ER stress. Interpretation: These results identify a novel role for Smurf2,which negatively regulate of PTX3 stability, and promote angiogenesis in ASMSCs. Funding: This study was financially supported by grants from the National Natural Science Foundation of China (81871750), the Science and Technology Project of GuangDong Province (2018A030313232, 2017A020215070), the Medical Science and Technology Research Project of GuangDong Province (A2018292), and the Key Realm R&D Programme of GuangDong Province (2019B020236001). Declaration of Interest: The authors have no potential conflicts of interest to declare. Ethical Approval: This study was approved by the Ethics Committee of the Eighth Affiliated Hospital, Sun Yat-sen University, Shenzhen, China.

Severe spinal cord injury (SCI) causes loss of neural connectivity and permanent functional deficits. Re-establishment of new neuronal relay circuits after SCI is therefore of paramount importance. The present study tested our hypothesis if co-culture of neurotrophin-3 (NT-3) gene-modified Schwann cells (SCs, NT-3-SCs) and TrkC (NT-3 receptor) gene-modified neural stem cells (NSCs, TrkC-NSCs) in a gelatin sponge scaffold could construct a tissue engineering neural network for re-establishing an anatomical neuronal relay after rat spinal cord transection. Eight weeks after transplantation, the neural network created a favorable microenvironment for axonal regeneration and for survival and synaptogenesis of NSC-derived neurons. Biotin conjugates of cholera toxin B subunit (b-CTB, a transneuronal tracer) was injected into the crushed sciatic nerve to label spinal cord neurons. Remarkably, not only ascending and descending nerve fibers, but also propriospinal neurons, made contacts with b-CTB positive NSC-derived neurons. Moreover, b-CTB positive NSC-derived neurons extended their axons making contacts with the motor neurons located in areas caudal to the injury/graft site of spinal cord. Further study showed that NT-3/TrkC interactions activated the PI3K/AKT/mTOR pathway and PI3K/AKT/CREB pathway affecting synaptogenesis of NSC-derived neurons. Together, our findings suggest that NT-3-mediated TrkC signaling plays an essential role in constructing a tissue engineering neural network thus representing a promising avenue for effective exogenous neuronal relay-based treatment for SCI.

Persistent neurotrophic factor delivery is crucial to create a microenvironment for cell survival and nerve regeneration in spinal cord injury (SCI). This study aimed to develop a NT-3/fibroin coated gelatin sponge scaffold (NF-GS) as a novel controlled artificial release therapy for SCI. In vitro, bone marrow-derived mesenchymal stem cells (MSCs) were planted into the NF-GS and release test showed that NF-GS was capable to generate a sustainable NT-3 release up to 28 days. MSCs in NF-GS had high cell activity with excellent cell distribution and phenotype. Then, the NF-GS was transplanted into the injury site of spinal cord of rat and canine in vivo, which exhibited strong biocompatibility during post-transplantation period. Four weeks following transplantation, the concentration of NT-3 was much higher than that in control groups. Cavity areas in the injury/graft site were significantly reduced due to tissue regeneration and axonal extensions associated with myelin sheath through the glial scar into the NF-GS. Additionally, the NF-GS decreased the inflammation by reducing the CD68 positive cells and TNF-α. A striking feature was the occurrence of some cells and myelin-like structure that appeared to traverse the NF-GS. The present results demonstrate that the NF-GS has the property to control the release of NT-3 from the NT-3/fibroin complex thus facilitating regeneration of injured spinal cord.

Death-associated protein kinase 1 (DAPK1) is a key protein that mediates neuronal death in ischemic stroke. Although the substrates of DAPK1 and molecular signal in stroke have been gradually discovered, the modulation of DAPK1 itself is still unclear. Here we first reveal that Caytaxin, a brain-specific member of BCL2/adenovirus E1B -interacting protein (BNIP-2), increases and interacts with DAPK1 as early as 2 h after middle cerebral artery occlusion (MCAO) in the penumbra area of mouse brain. Furthermore, Caytaxin binds to DAPK1 at the presynaptic site and inhibits DAPK1 catalytic activity. Silencing Caytaxin by Caytaxin shRNA (Sh-Caytaxin) enhances DAPK1 activity, deteriorates neuronal apoptosis and brain injuries both in vivo and in vitro. Thus, elevating presynaptic Caytaxin could prevent neuronal apoptosis by inhibiting DAPK1 activation in the acute stage of ischemic stroke. Caytaxin may physiologically protect neuronal cells and represent a potential prevention and therapeutic target in the early phase of cerebral ischemic stroke.

A stable water-based magnetic fluid was prepared by synthesizing sodium oleate bilayer-coated Fe3O4 nanoparticles via chemical coprecipitation. The adsorption mechanism about excessive sodium oleate coated on particles’ surfaces below and above the isoelectric point of Fe3O4 colloid was proposed. Based on this, a novel and facile phase-transform method to transform hydrophilic particles to lipophilic ones has been schemed by adjusting pH value or adding ethanol. The results showed two different transformation mechanisms. In the acid precipitation method, the bilayer-coated structure was retained, which made the hexane magnetic fluid more stable.

Background context The understanding of vascular supply to the spinal cord is important given that the evolution of surgical approaches to the spine may bring along the potential for more frequent complications, especially a rare but devastating complication: that of spinal cord ischemia or infarction. To maximally avoid this complication, the relationship between the spinal cord vascularity and the anterior spine surgical approach needs further study. Purpose To provide a theoretical basis that will allow the spinal surgeon to take appropriate steps to avoid spinal cord ischemia during anterior spinal surgery through anatomic means. Study design Spinal cord vascular casting assessment with cadaveric specimen. Methods Twenty adult cadaveric specimens (11 men and 9 women) were obtained for the latex perfusion and vessel dissection. In addition, nine patients (seven men and two women) underwent superselective angiography of the spinal cord. The segmental arterial anastomosis and radiculomedullary vessels in the thoracolumbar region were shown and reviewed. Results There were approximately 21 pairs of segmental arteries in the thoracolumbar region. Adjacent segmental arteries were networked with each other. The latex infusion specimens demonstrated 72 anterior radiculomedullary arteries and 177 posterior radiculomedullary arteries in all 20 samples. The anterior and posterior spinal arteries were also networked with each other at several levels. Superselective spinal angiography was consistent with the latex infusion specimens showing. Conclusions The variety of anatomy of spinal cord arterial networks is shown, and the relation between the blood supply of certain spinal levels and the potential ischemic complications during the anterior surgical approach is discussed. It is hopefully of benefit to surgeons, after fully understanding the anatomy of these spinal vascular supply structures, that there may be even greater avoidance of vascular compromise in these challenging operations.

A new method named Chemical Physics (CP) method was developed to produce solar grade silicon feedstock at a company in China. In this paper the characteristic of the solar grade silicon made by CP method was analysed. The results show that the purity of solar grade silicon is above 5 N and most of impurities are below 0.0001 wt.%. Crystalline silicon solar cells were prepared using solar grade silicon wafers based on CP method. Average efficiency of the solar cells is about 15.05%, and the highest efficiency is 15.60% under AM1.5 illumination conditions. The light-induced degradation of the solar cells was examined. Degradation by up to 15% of the initial efficiency of the solar cells is detected. The solar cell results and light-induced characteristic show that the solar cells based on CP methods have desired performance and thus have the potential for large scale production.

The aim of this study was to test the sensitivity and specificity of diffusion-weighted MRI for the detection of acute spinal cord injury. Forty female New Zealand white rabbits were randomly divided into four groups: the mild, moderate and severe injury groups, and the control (sham operation) group. Contusion of the spinal cord was induced using a weight-drop impactor. All animals were imaged using T1-weighted, T2-weighted, and diffusion-weighted imaging (DWI) sequences at 30 minutes, 6 hours, and 24 hours after injury. One animal from each group was killed at each time point for histologic examination of the spinal cord. DWI had a sensitivity of 100% at all time points, whereas T2-weighted MRI had a sensitivity of 43.33% at 30 minutes after injury, 81.48% at 6 hours after injury, and 95.83% at 24 hours after injury. Conversely, the specificity of DWI was lower than that of T2-weighted MRI at all time points. One animal in the control group had a non-specific high signal on DWI. Significant systematic differences were seen between DWI and T2-weighted MRI at both 30 minutes and 6 hours after injury. The apparent diffusion coefficient values of the lesion were lower than those of adjacent unaffected regions in the mild and moderate injury groups, but higher than adjacent unaffected regions in the severe injury group. The histological findings were reliably correlated with the magnetic resonance findings. We found that DWI has a higher sensitivity, but a lower specificity, than conventional MRI for the detection of early pathological changes after contusive injury.

Sox9 is a key transcription factor which plays an important role in chondrogenesis. Although Bone Morphogenetic Protein-2 (BMP-2) has been reported to induce Sox9 expression, the underlying molecular mechanism remains elusive. Here, we used in vivo approaches to characterize BMP-2-induced alterations in chromatin organization around the Sox9 core promoter. Nuclease hypersensitive site mapping following BMP-2 stimulation showed an inducible hypersensitive site in the Sox9 proximal promoter. Immunoprecipitation (IP) experiments demonstrated that BMP-2 increased the association of the transcription factor NF-Y with histone acetyltransferase p300/CBP. Chromatin immunoprecipitation (ChIP) analysis showed the binding of the NF-Y–p300 complex to the Sox9 gene proximal promoter along with PCAF and RNA polymerase II. We also found that BMP-2 stimulation caused histone hyperacetylation and methylation at the Sox9 gene. Collectively, these data suggest that the activation of Sox9 gene transcription by BMP-2 is associated with chromatin remodeling and histone modification.

The adsorption process of different dextran molecules onto the surface of in water dispersed magnetite nanoparticles has been investigated to optimize the preparation of magnetite magnetic fluids (MMFs). An average magnetite core size of 7.1 nm was found by X-ray diffraction and that of 8 nm was found by transmission electron microscopy for the samples prepared at 90 °C. An average hydrodynamic diameter of 25 nm was observed by scanning electron microscopy and that of 25–300 nm was obtained by photon correlation spectroscopy. The dextran was adsorbed by physical adsorption, a molecular weight of 20 kDa gave the best stability of these MMFs. The shell layer of the particles was weakly negatively charged in buffer solutions of pH values between 5.5 and 9.5. The particles seem to be mainly stabilized by sterical repulsion. The maximum available saturation magnetization of the MMFs was 3.5 kA/m.

The adsorption of N-oleoylsarcosine onto in water dispersed magnetite nanoparticles were investigated at different concentrations and pH values. The coated nanoparticles surface became hydrophobic at a molar ratio of N-oleoylsarcosine:Fe3O4 below 0.22:1 within a pH range of 5–9.5. Aqueous-based magnetic fluids could not be obtained. A hydrophilic surface was observed at a molar ratio of N-oleoylsarcosine:Fe3O4 above 0.37:1 and at pH levels ranging from 6 to 8.5. Stable aqueous-based magnetic fluids could be prepared. The magnetite particles flocculate at pH levels below 5.5 or above 8.5. The hydrophobic behavior was explained assuming a monolayer adsorption mode. On the other hand, the hydrophilic properties were caused by a bilayer adsorption structure. This hypothesis was in overestimation with results of infrared (IR) spectroscopy and photon correlation spectroscopy of the prepared magnetic fluids. The influences of pH levels on the formation of N-oleoylsarcosine micelles were also discussed to explain the pH-dependant formation of bilayer adsorption structure, i.e. surface small micelle structure. It was indicated that it became difficult for N-oleoylsarcosine adsorb at the water–air interface, or adsorb at the nanoparticles surfaces in the form of surface small micelles at pH levels above 8.5. Besides, the aqueous-based magnetic fluids were also characterized by magnetization curve determinations.