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Background: Diabetic cardiomyopathy (DCM) is the leading cause of diabetic death as the final occurrence of heart failure and arrhythmia. Traditional Chinese medicine is usually used to treat various diseases including diabetes. Objective: This study sought to investigate the effects of Traditional Chinese medicine supplementing Qi and activating blood circulation (SAC) in DCM. Methods: After the construction of the DCM model by streptozotocin (STZ) injection and high glucose/fat diet feeding, rats were administered intragastrically with SAC. Then, cardiac systolic/diastolic function was evaluated by detecting left ventricular systolic pressure (LVSP), maximal rate of left ventricular pressure rise (+LVdp/dtmax), and fall (-LVdp/dtmax), heart rate (HR), left ventricular ejection fraction (EF), LV fractional shortening (FS) and left ventricular end-diastolic pressure (LVEDP). Masson’s and TUNEL staining were used to assess fibrosis and cardiomyocyte apoptosis. Results: DCM rats exhibited impaired cardiac systolic/diastolic function manifested by decreasing LVSP, +LVdp/dtmax, -LVdp/dtmax, HR, EF and FS, and increasing LVEDP. Intriguingly, traditional Chinese medicine SAC alleviated the above-mentioned symptoms, indicating a potential role in improving cardiac function. Masson’s staining substantiated that SAC antagonized the increased collagen deposition and interstitial fibrosis area and the elevations in protein expression of fibrosis-related collagen I and fibronectin in heart tissues of DCM rats. Furthermore, TUNEL staining confirmed that traditional Chinese medicine SAC also attenuated cardiomyocyte apoptosis in DCM rats. Mechanically, DCM rats showed the aberrant activation of the TGF-β/Smad signaling, which was inhibited after SAC. Conclusion: SAC may exert cardiac protective efficacy in DCM rats via the TGF-β/Smad signaling, indicating a new promising therapeutic approach for DCM.

Objective. Ruanmailing oral solution consists of 16 herbs, has anti-lipid peroxidation activity, protects vascular endothelial cells, and improves vascular elasticity. It is an effective drug for the treatment of atherosclerosis (AS). The objective of this study was to investigate the mechanism underlying the antiatherosclerotic effects of Ruanmailing oral solution. Methods. Macrophages were isolated, cultured, and divided into the macrophage control; macrophage foam cell; and low-, medium-, and high-concentration Ruanmailing groups. Cell proliferation was analyzed by cell counting kit-8 (CCK-8) assay, and the expression levels of inward-rectifier potassium ion channel 2.1 (Kir2.1) and tumor necrosis factor (TNF)-α were detected by reverse transcription-polymerase chain reaction (RT-PCR) and Western blot analyses. Results. CCK-8 assay results showed that the tested concentrations of Ruanmailing solution did not affect macrophage proliferation. RT-PCR and Western blot assays indicated that TNF-α expression increased significantly with the formation of macrophage foam cells (P

Inhibitors of the protein–protein interaction (PPI) between the SARS-CoV-2 spike protein and human ACE2 (hACE2), which acts as a ligand–receptor pair that initiates the viral attachment and cellular entry of this coronavirus causing the ongoing COVID-19 pandemic, are of considerable interest as potential antiviral agents. While blockade of such PPIs with small molecules is more challenging than that with antibodies, small-molecule inhibitors (SMIs) might offer alternatives that are less strain- and mutation-sensitive, suitable for oral or inhaled administration, and more controllable/less immunogenic. Here, we report the identification of SMIs of this PPI by screening our compound library focused around the chemical space of organic dyes. Among promising candidates identified, several dyes (Congo red, direct violet 1, Evans blue) and novel druglike compounds (DRI-C23041, DRI-C91005) inhibited the interaction of hACE2 with the spike proteins of SARS-CoV-2 as well as SARS-CoV with low micromolar activity in our cell-free ELISA-type assays (IC50’s of 0.2–3.0 μM), whereas control compounds, such as sunset yellow FCF, chloroquine, and suramin, showed no activity. Protein thermal shift assays indicated that the SMIs of interest identified here bind SARS-CoV-2-S and not hACE2. While dyes seemed to be promiscuous inhibitors, DRI-C23041 showed some selectivity and inhibited the entry of two different SARS-CoV-2-S expressing pseudoviruses into hACE2-expressing cells in a concentration-dependent manner with low micromolar IC50’s (6–7 μM). This provides proof-of-principle evidence for the feasibility of small-molecule inhibition of PPIs critical for SARS-CoV-2 attachment/entry and serves as a first guide in the search for SMI-based alternative antiviral therapies for the prevention and treatment of diseases caused by coronaviruses in general and COVID-19 in particular.

A Cu-Fe-Cr-Ag alloy was prepared by directional solidification (DS) and upward continuous casting (UCC) to study the effect of different casting methods on the structure and properties of Cu-Fe-Cr-Ag. The results showed that the directionally solidified Cu-Fe-Cr-Ag alloy had excellent mechanical properties and conductivity. After cold drawing and isothermal aging, the peak tensile strength (789 MPa) and peak conductivity (65.5 pct IACS) of directionally solidified Cu-Fe-Cr-Ag alloy were 21 MPa and 4.7 pct IACS higher, respectively, than those that of the upward continuously casted Cu-Fe-Cr-Ag alloy. Compared to upward continuously casted Cu-Fe-Cr-Ag alloy, the Fe dendrites in directionally solidified Cu-Fe-Cr-Ag alloy were much finer, more uniform, and arranged along the direction of the magnetic field. Cu and Ag formed a Cu-Ag eutectic structure at the edge of the directionally solidified Cu-Fe-Cr-Ag alloy rod. After multi-stage thermomechanical treatment, Ag was mainly distributed around the material and formed a structure similar to Ag-clad Cu. The directionally solidified Cu-Fe-Cr-Ag alloy had a smaller lattice constant and finer Fe fibers. The small lattice constant and Fe fibers and the special distribution of Ag lead to the excellent comprehensive performance of the directionally solidified Cu-Fe-Cr-Ag alloy.

Background Osteosarcoma (OS) is a common type of bone malignancy that often occurs in children and adolescents. Chemoresistance is a huge barrier to cancer therapy. This study aimed to investigate the role and potential mechanism of circ_0001721 in doxorubicin (DXR) resistance and OS development. Methods The levels of circ_0001721, miR-758 and transcription factor 4 (TCF4) were detected by quantitative real-time polymerase chain reaction or western blot assay. Cell Counting Kit-8 (CCK-8) assay was used to calculate the half inhibition concentration (IC50) of DXR and assess cell viability. Cell migration and invasion were evaluated by transwell assay. Cell apoptosis was monitored by flow cytometry. The levels of multidrug resistance-related and Wnt/β-catenin pathway-related proteins were measured by western blot assay. The interaction among circ_0001721, miR-758 and TCF4 were confirmed by dual-luciferase reporter assay, RNA immunoprecipitation assay or RNA pull-down assay. The xenograft model was established to analyze tumor growth in vivo. Results Circ_0001721 and TCF4 were upregulated, whereas miR-758 was down-regulated in DXR-resistant OS tissues and cells. Circ_0001721 silence reduced DXR resistance of KHOS/DXR and MG63/DXR cells. Circ_0001721 regulated DXR resistance via sponging miR-758. Moreover, miR-758 modulated DXR resistance by targeting TCF4. Besides, circ_0001721 knockdown inhibited tumor growth in vivo. Conclusion Circ_0001721 potentiated DXR resistance and facilitated the progression of OS by regulating miR-758/TCF4 axis, which provides promising therapeutic targets for OS treatment.

The mechanical properties and microstructure transformation of Cu Cr Zr alloys obtained by upward continuous casting with varying Zr contents were studied by optical microscopy (OM), electron backscattered diffraction (EBSD) and transmission electron microscopy (TEM) after cold drawing with different strain and heat treatment. The results show that good strength can be obtained through cold drawing with suitable heat treatment. The peak tensile strength can achieve 587.8 MPa and the peak yield strength can reach 499.6 MPa; The difference of yield strength of Cu Cr Zr alloy during cold drawing deformation becomes larger with the increase of Zr element content when the strain gradually improves; The increase of the Zr element will promote the recrystallization of the alloy at aging after cold drawing, refining the crystal grains. It contributes about 70% of the increase in strength, act as a fine grain strengthening effect, increasing the strength of the alloy.

Interfacial reactions between Sn–3.0Ag–0.5Cu–1.0Ga/1.5Ga in wt.% solders and Cu substrates have been investigated. The solder and substrate couples were annealed at 180°C for 6, 12, 18, and 24 days. Different layers of intermetallic compounds have been found to form, such as Cu6Sn5 and Cu9Ga4. Sn was also observed within the interfacial layer during the annealing. The Cu6Sn5 phase and the Cu9Ga4 phase were observed to form by turns from the substrate into the solder. The Cu9Ga4 phase grew from both the solder side and the intermetallics side. Growth of the Cu9Ga4 phase was found to depend on the Ga diffusion and the availability of the Cu6Sn5 phase.

BackgroundTo investigate the effect of Ruanmailing oral liquid on atherosclerosis and TGF-β1/SMAD4 signaling pathway in ApoE knockout mice induced by high-fat diet. MethodsForty ApoE-/- mice were randomly divided into 5 groups, and mice fed with standard diets were the control group. ApoE-/- mice high-fat diet induced atherosclerotic phenotype. After grouping and treatment, they were divided into high-fat feeding model group, low-dose and high-dose of Ruanmailing groups (1.75, 4.55 ml/kg/d), Lipitor Group (3.0 mg/kg/d). After 12 weeks of administration, blood was collected from the mice orbit to determine the levels of TC, TG, LDL-C, and HDL-C, and the pathological changes of thoracic aorta atherosclerosis were observed. Enzyme-linked immunosorbent assay (ELISA) was used to detect the concentration of serum TGF-β1, and RT-PCR and Western Blot were used to detect the expression of SMAD4 and GATA2 in the thoracic aorta of ApoE-/- mice in each group. ResultsCompared with the high-fat model group, the serum lipids level of each administration group were reduced (PPP-/- mice were alleviated, and the high-dose Ruanmailing group had the most significant anti-atherosclerotic effect. ConclusionsRuanmailing oral liquid has an anti-atherosclerotic effect, and its mechanism may be related to the intervention of GATA2 in the TGF-β1/SMAD4 signaling pathway to reduce the differentiation and proliferation of arterial smooth muscle cells.

Inhibitors of the protein-protein interaction (PPI) between the SARS-CoV-2 spike protein and ACE2, which acts as a ligand-receptor pair that initiates the viral attachment and cellular entry of this coronavirus causing the ongoing COVID-19 pandemic, are of considerable interest as potential antiviral agents. While blockade of such PPIs with small molecules is more challenging than with antibodies, small-molecule inhibitors (SMIs) might offer alternatives that are less strain- and mutation-sensitive, suitable for oral or inhaled administration, and more controllable / less immunogenic. Here, we report the identification of SMIs of this PPI by screening our compound-library that is focused on the chemical space of organic dyes. Among promising candidates identified, several dyes (Congo red, direct violet 1, Evans blue) and novel drug-like compounds (DRI-C23041, DRI-C91005) inhibited the interaction of hACE2 with the spike proteins of SARS-CoV-2 as well as SARS-CoV with low micromolar activity in our cell-free ELISA-type assays (IC50s of 0.2-3.0 μM); whereas, control compounds, such as sunset yellow FCF, chloroquine, and suramin, showed no activity. Protein thermal shift assays indicated that the SMIs identified here bind SARS-CoV-2-S and not ACE2. Selected promising compounds inhibited the entry of a SARS-CoV-2-S expressing pseudovirus into ACE2-expressing cells in concentration-dependent manner with low micromolar IC50s (6-30 μM). This provides proof-of-principle evidence for the feasibility of small-molecule inhibition of PPIs critical for coronavirus attachment/entry and serves as a first guide in the search for SMI-based alternative antiviral therapies for the prevention and treatment of diseases caused by coronaviruses in general and COVID-19 in particular.

Background This study aimed to explore the relationship among different cervical sagittal parameters in asymptomatic volunteers and the correlation between surgical efficacy and difference of presumed and actual postoperative C2–7 Cobbs’s angle (C2–7COBB), which was calculated based on preoperative T1 slope (T1S) in patients undergoing cervical reconstruction. Methods In total, 158 inpatients with cervical spondylosis and 274 asymptomatic volunteers were retrospectively reviewed. Cervical sagittal parameters, such as C2–7COBB, T1S, thoracic inlet angle (TIA), and neck tilt (NT), were compared. Then, the correlation among these parameters was analyzed in asymptomatic volunteers, and a regression equation between T1S and C2–7COBB was established and used to analyze the correlation among the Japanese Orthopaedic Association (JOA) score improvement, the sagittal parameters, and the difference between presumed and actual postoperative C2–7COBB in patients after cervical reconstruction. Results The mean T1S, C2–7COBB, and TIA were significantly decreased in patients (P < 0.01). T1S and NT had a strong correlation with TIA (P < 0.01). T1S demonstrated a moderate correlation with C2–7COBB in asymptomatic volunteers (r = 0.569, P < 0.01). A regression equation had been established as C2–7COBB = 0.742 × T1S − 0.866. The mean C2–7COBB and JOA score improved significantly (P < 0.05) postoperatively. Moreover, the JOA improvement rate showed a significant negative correlation with the difference in the presumed and actual postoperative C2–7COBB (r = − 0.696, P < 0.01). Conclusion Our study successfully established a regression equation for calculating postsurgical C2–7COBB based on the correlation between T1S and C2–7COBB in asymptomatic volunteers. The regression equation could be used for guiding surgeons to accomplish an ideal postsurgical C2–7COBB for patients with cervical spondylosis.

The coarsening behavior of (Ni, Co)2Si particles in Cu–Ni–Co–Si alloy was investigated by experimental observations and coarsening kinetics calculations when aged at 450, 500, 550 and 600 °C for different durations. The results show that the critical particle radius for coherence mismatch is found to be 10.3 nm, and particles larger than 25 nm are generally semi-coherent. The relationship of (Ni, Co)2Si particles size and aging time follows Lifshitz, Slyosov and Wagner (LSW) theory. The particle size distributions fit well to the LSW theoretical distribution. The activation energy for (Ni, Co)2Si coarsening is accurately determined to be (216.21 ± 5.18) kJ·mol−1 when considering the effect of temperature on the solution concentrations in matrix. The coarsening of (Ni, Co)2Si particles in Cu–Ni–Co–Si alloy is controlled by diffusion of Ni, Co and Si in Cu matrix. The growth of particles for long durations suggests that vacancies can be trapped within the structure for long time despite their mobility.

Yttria-reinforced copper matrix composites were prepared by dry ball milling (DBM) and wet ball milling (WBM), respectively, followed by spark plasma sintering (SPS). It is to determine which milling process is better for fabricating Cu–Y2O3 composites. It is found that Cu–Y2O3 composites synthesized by DBM exhibit better densification, mechanical and electrical properties than those by WBM. Less agglomeration of reinforcements in the bulk composites by DBM is responsible for the better performances. To further understand the reason of less agglomeration of Y2O3 in the bulks by DBM, morphologies of prepared powders were investigated and analyzed. Higher ball’s impact energy and the formation of copper oxide on the matrix surface during DBM process contribute to small matrix particles, which is beneficial for less agglomeration.

Cu-6.5Fe-0.2Cr (CFC) and Cu-6.5Fe-0.2Cr-1Ag (CFCA) alloys were prepared by upward continuous casting to investigate the influence of Ag on the microstructure, mechanical properties and electrical properties of CFC alloy. The properties testing discovered that the mechanical properties and electrical conductivity of CFC alloy were improved by the addition of Ag. The peak strength of CFCA alloy (622 MPa) was 33 MPa higher than that of CFC alloy, and the peak conductivity (67.8% IACS) was increased by 5% IACS after aging. The microstructure observation showed that Cr element was mainly distributed in the primary Fe phase. The addition of Ag refined and promoted the precipitation of nano-scale Fe phase, and improved the coordinated deformation ability of Cu/Fe, resulting in excellent comprehensive performance of CFCA alloy. In addition, the effect of Ag on nano-scale Fe phase precipitation kinetics was explored by the modified Johnson–Mehl–Avrami–Kolmogorov (JMAK). The addition of Ag reduced the activation energy of the Fe phase and promoted the precipitation kinetics of the Fe phase. And the activation energy of CFC and CFCA alloys was 66.1 and 63 kJ/mol, respectively.

The effects of deformation on the aging precipitation behavior, recrystallization behavior and mechanical properties of Cu–15Ni–8Sn and Cu–15Ni–8Sn-0.2P alloys were investigated using scanning electron microscopy, high-resolution transmission spectroscopy, and electron backscatter diffraction. The results showed that during the aging process, the transformation from DO22 to the L12 ordered phase was restrained after cold deformation. However, the coarsening of the modulated structure was promoted. Moreover, the joint effect of discontinuous precipitation (DP) and recrystallization led to the deterioration of the mechanical properties in the late aging stage. The deterioration of the properties caused by DP was much more significant than that caused by recrystallization. Compared to the deformed Cu–15Ni–8Sn alloy, the deformed Cu–15Ni–8Sn-0.2P alloy was more prone to recrystallization reactions. This ultimately inhibited the DP during the aging process. Furthermore, the addition of P in the Cu–15Ni–8Sn alloy improved the peak values of the hardness and ultimate tensile strength, and had a negligible effect on the elastic modulus. The peak-age values of the ultimate tensile strength (yield strength) and elastic modulus of the 70%-cold-deformed Cu–15Ni–8Sn-0.2P aged at 400 °C were 1303 MPa (1280 MPa) and 145.0 GPa, respectively. Nevertheless, our results suggested that the precipitation strengthening, dislocation strengthening, and solution strengthening were the major strengthening mechanisms that improved the yield strength of the Cu–15Ni–8Sn-(P) alloy. The grain boundary strengthening had a negligible effect on the properties of the alloy. Compared to the Cu–15Ni–8Sn alloy, the increase in the yield strength of the Cu–15Ni–8Sn-0.2P alloy was mainly affected by precipitation strengthening.

Study design Retrospective comparative study. Objective To compare the outcomes of C1-C2 transarticular screw with C1 laminar hook (TAS + C1H) fixation and C1 trans-arch lateral mass screw with C2 pedicle screw (C1TLMS + C2PS) fixation in the treatment of reducible atlantoaxial dislocation (AAD). Summary of background data TAS + C1H is comparable to TAS with posterior wiring techniques and superior to C1 lateral mass screw combined with C2 pedicle screw (C1LMS + C2PS) in biomechanics. There were, however, few studies analyzing the differences in outcomes between TAS + C1H technique and modified C1LMS + C2PS technique (C1TLMS + C2PS) for treating AAD. Methods Data of 30 patients with reducible AAD treated by TAS + C1H fixation and another 30 cases treated by C1TLMS + C2PS fixation were retrospectively analyzed. Bone fusion time was recorded. The outcomes evaluated by American Spinal Injury Association impairment scale, visual analog scale score for neck pain, neck stiffness (none/mild/severe), patient satisfaction, and Neck Disability Index (NDI) were compared between two groups. Results There were no complications related to the surgical approach and instrumentation in either group. At the final follow-up, bone graft fusion rates were 100% in both the TAS + C1H fixation group and the C1TLMS + C2PS fixation group (P > 0.05). The neurological status evaluated by American Spinal Injury Association impairment scale were greatly improved in both screw-hook group (P 0.05). There were no significant differences between two groups in visual analog scale score for neck pain, neck stiffness, patient satisfaction, or Neck Disability Index (all P > 0.05). Conclusion C1TLMS + C2PS fixation was comparable to TAS + C1H fixation in fusion rate and functional outcomes for treating reducible AAD. To reduce the risk of vertebral artery injury, computed tomography scan, and reconstruction should be done to analyze vertebral artery course and C1-C2 anatomic structures before operation. Level of evidence 3.

Upward continuous casting was used to manufacture Cu-Cr-Ag high-strength high-conductivity alloys, for comparison with conventional processing methods. The behavior of the alloy samples was measured, including tensile strength, microhardness, and electrical conductivity. The microstructure was characterized using optical microscopy and transmission electron microscopy after each processing step. It was found that microstructure with columnar grains due to upward continuous casting made it possible to enhance strength whilst maintaining the ductility of the alloys during the aging process. The combined drawing-aging process has the potential to be used numerous times during the manufacture of Cu-Cr-based high-strength high-conductivity alloys.

The microstructure and subsequent phase transformations of Cu-15Ni-8Sn can get affected by a minor addition of phosphorus (P). For the first time, the hexagonal Ni10SnP3 phase was observed in the Cu-15Ni-8Sn-0.2P alloy using high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) and transmission electron microscope (TEM). Further, the atomic size factor increased which was responsible for the promotion of the spinodal decomposition and ordering in Cu-15Ni-8Sn alloy with P addition. Moreover, the Ni10SnP3 phase precipitated along the grain boundary, and the precipitation free-zone was observed near the grain boundary. Nonetheless, these were the primary causes observed for the inhibition of discontinuous precipitation (DP) with P addition.

Objectives Retro-odontoid pseudotumor (ROP), with no rheumatoid arthritis, atlantoaxial instability, or other primary diseases, is defined as idiopathic retro-odontoid pseudotumor (IROP). Cervical spine degeneration is associated with IROP development. This study aims to evaluate the effect of cervical spine degeneration on the atlantoaxial complex and find the possible biomechanical mechanism of IROP development. Methods This study was performed using a three-dimensional (3D) finite element (FE) analysis. A degenerated FE model (FEM) and five operation FEMs (C1-C2 fusion, C0-C2 fusion, C0-C3 fusion, C0-C4 fusion, and C1 posterior arch resection) were established based on a normal 3D FEM of the cervical spine including C0-T1 with the main ligaments and muscles. The parameters, including the C1-C2 range of motions (ROMs) and odontoid-related ligaments’ stresses in degenerated and operation FEMs, were obtained and compared with those in normal FEM. Results Compared to normal FEM, degenerated FEM had reduced C3-C7 ROMs and increased C1-C2 ROMs and odontoid-related ligaments’ stresses. After internal fixation, C1-C2 ROMs and most odontoid-related ligaments’ stresses were greatly decreased, but with no significant differences among C0-C2, C0-C3, C0-C4, and C1-C2 fusion models. For the C1 posterior arch resection model, C1-C2 ROMs and most odontoid-related ligaments’ stresses increased, compared with normal FEM. Conclusions Cervical spine degeneration plays an important part in IROP development in biomechanics. Atlantoaxial complex compensates for cervical spine degeneration, with increased C1-C2 ROMs and odontoid-related ligaments’ stresses. Atlantoaxial fusion or short segmental occipitocervical fusion can effectively reduce the stress and should be considered in IROP treatment.

This paper presents a nonlinear model predictive control (NMPC) approach based on support vector machine (SVM) and genetic algorithm (GA) for multiple-input multiple-output (MIMO) nonlinear systems. Individual SVM is used to approximate each output of the controlled plant. Then the model is used in MPC control scheme to predict the outputs of the controlled plant. The optimal control sequence is calculated using GA with elite preserve strategy. Simulation results of a typical MIMO nonlinear system show that this method has a good ability of set points tracking and disturbance rejection.

The mechanical properties and microstructure transformation of Cu–15Ni–8Sn-xFe (x = 0, 0.1, 0.3, 0.5, wt. %) alloys prepared by vacuum induction melting were investigated by using optical microscopy (OM), atom-probe tomography (APT) and scanning transmission electron microscopy (STEM). The results showed that the addition of Fe in Cu–15Ni–8Sn alloy could improve the anti-aging resistance, hardness and tensile properties. Further, when the Fe content is 0.1%, the maximum hardness, ultimate tensile strength and yield strength of the alloy were 30 HV, 123 MPa and 58 MPa higher than that of the Fe-free alloy, respectively. Through APT analysis, it is found that Fe was mainly enriched at the core of the DO22 ordered phase, which probably the key factor to improve the performance. Moreover, the inhibition of the discontinuous precipitation (DP) was related to the increases in the interlamellar spacing of DP, the decrease in the solute diffusivity along the advancing boundary, and increase in the stability of the DO22 ordered phase.

The low cycle fatigue behavior (Δet/2 = 0.4–1.0%) of a Cu-Cr-Zr alloy strengthened with nanoscale precipitates has been tested at room temperature. The results showed that cyclic softening occurs under all Δet/2 after cyclic hardening. However, the Cu-Cr-Zr alloy exhibited secondary cycle hardening after a brief softening at high Δet/2 (0.8%, 1.0%). In strong contrast to the fatigue fracture surface at Δet/2 = 0.4%, Δet/2 = 1.0% was characterized by multiple fatigue sources and obvious fatigue striations. Moreover, a sawtooth-like feature formed and the fracture mode was mainly brittle with few regions of ductile aspects. Compared with the original characteristics, the microstructure after different values of Δet/2 was markedly different, and the dislocation density gradually increased with the increases of Δet/2.

Retrospective comparative study.To compare the outcomes of C1-C2 transarticular screw combined with C1 laminar hook (TAS+C1H) and C1-C2 transarticular screw combined with modified Gallie technique (TAS+G) for treating reducible atlantoaxial dislocation (AAD).Both TAS+C1H and TAS+G fixation were 3-point fixation techniques for AAD. TAS+C1H technique was comparable to TAS+G technique in biomechanics. However, it is unknown whether it can achieve same outcomes as TAS+G technique.Data of the 63 patients who underwent TAS+C1H or TAS+G fixation and fusion because of AAD were retrospectively reviewed. Bone fusion time was recorded. The outcomes evaluated by visual analog scale score for neck pain (VASSNP), Nurick scale, neck stiffness (none/mild/severe), patient satisfaction, and Neck Disability Index (NDI) were compared between two groups.At the final follow-up, bone graft fusion rates were 100% in both groups (P 0.05). Nurick scales were significantly improved in both groups (P 0.05), but with no significant differences between groups (P 0.05). There were no significant differences between two groups in VASSNP, neck stiffness, patient satisfaction, or NDI (all P 0.05). There were no complications related to the surgical approach and instrumentation in either group.Both TAS+C1H and TAS+G fixation were effective in the treatment of reducible AAD. TAS+C1H was safer than TAS+G because it could potentially reduce the risk of spinal cord and venous plexus injury associated with sublaminar cables.3.