Design of electromagnetic tracking system for puncture needle of an intelligent puncture robot.

OBJECTIVES: The puncture needle of an intelligent puncture robot must accurately reach the target location early in the diagnosis of benign and malignant nodules and in the puncture ablation of malignant tumors. To track the position and the orientation of the puncture needle tip, an electromagnetic tracking system based on adaptive adjustment of excitation intensity and lock-in amplification is proposed. METHODS: The system includes a time-sharing excitation device with multiple magnetic sources, a magnetic sensor, a signal processing device based on dual-phase lock-in amplifiers and a computing platform in the upper computer. With adaptive adjustment of excitation intensity, the time-sharing excitation device uses a microcontroller to control a direct digital synthesizer. Based on feedback from the magnetic sensor, the microcontroller time-shares the power amplifier to generate the required excitation current. Dual-phase lock-in amplifiers demodulate the magnetic sensor output after preamplification and filtering. Through analog-to-digital conversion and the serial interface, the digital signal is sent to the computing platform for solving by neighborhood particle swarm optimization algorithm, and the position and orientation of the puncture needle fixed with the magnetic sensor are obtained. RESULTS: The experimental results within a 300 mm×300 mm×300 mm space show average position errors of 0.4467 cm (X-axis), 0.4154 cm (Y-axis), and 0.3766 cm (Z-axis). The overall average position error is 0.4129 cm, with a root mean square error of 0.4970 cm. CONCLUSIONS: The proposed electromagnetic tracking system can track the needle position and orientation of puncture robots in real-time, thereby enhancing puncture success rates and reducing puncture times.

Bone marrow mesenchymal stem cells paracrine TGF-ß1 to mediate the biological activity of osteoblasts in bone repair.

BACKGROUND: Bone marrow mesenchymal stem cells (BMSCs) are an important source of seed cells for regenerative medicine and tissue engineering therapy. BMSCs have multiple differentiation potentials and can release paracrine factors to facilitate tissue repair. Although the role of the osteogenic differentiation of BMSCs has been fully confirmed, the function and mechanism of BMSC paracrine factors in bone repair are still largely unclear. This study aimed to determine the roles of transforming growth factor beta-1 (TGF-ß1) produced by BMSCs in bone tissue repair. METHODS: To confirm our hypothesis, we used a Transwell system to coculture hBMSCs and human osteoblast-like cells without contact, which could not only avoid the interference of the osteogenic differentiation of hBMSCs but also establish the cell-cell relationship between hBMSCs and human osteoblast-like cells and provide stable paracrine substances. In the transwell coculture system, alkaline phosphatase activity, mineralized nodule formation, cell migration and chemotaxis analysis assays were conducted. RESULTS: Osteogenesis, migration and chemotaxis of osteoblast-like cells were regulated by BMSCs in a paracrine manner via the upregulation of osteogenic and migration-associated genes. A TGF-ß receptor I inhibitor (LY3200882) significantly antagonized BMSC-induced biological activity and related gene expression in osteoblast-like cells. Interestingly, coculture with osteoblast-like cells significantly increased the production of TGF-ß1 by BMSCs, and there was potential intercellular communication between BMSCs and osteoblast-like cells. CONCLUSIONS: Our findings provide evidence that the biological mechanism of BMSC-produced TGF-ß1 promotes bone regeneration and repair, providing a theoretical basis and new directions for the application of BMSC transplantation in the treatment of osteonecrosis and bone injury.

Total Synthesis of (+)-Alsmaphorazine†C and Formal Synthesis of (+)-Strictamine: A Photo-Fries Approach.

A bioinspired photo-Fries/imine capture cascade reaction was developed in continuous-flow mode, which facilitated the rapid construction of a series of diversely functionalized 2,7-heterocycle-fused tetrahydrocarbazoles, the ubiquitous core structures embedded in strychnos and akuammiline-type monoterpene indole alkaloids. The synthetic utility of this novel method has been preliminarily explored by the first total synthesis of (+)-alsmaphorazine C and formal synthesis of (+)-strictamine in a concise and efficient manner.

Arthroscopic partial meniscectomy combined with medical exercise therapy versus isolated medical exercise therapy for degenerative meniscal tear: A meta-analysis of randomized controlled trials.

BACKGROUND: Degenerative meniscal tear is a chronic disorder which presents with knee pain, swelling and loss of motion. It is currently unknown whether arthroscopic partial meniscectomy combined with medical exercise therapy is superior to isolated medical exercise therapy for degenerative meniscal tear. OBJECTIVE: To determine if medical exercise therapy alone is as effective as arthroscopic partial meniscectomy combined with medical exercise therapy in treating degenerative meniscal tear. METHOD: Electronic searches were performed using MEDLINE, EMBASE, and the Cochrane Library Databases for all randomized studies. Two reviewers independently completed the literature screening, data extraction, and risk evaluation of bias. The outcome measures were visual analogue scale (VAS), the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), range of motion, the Lysholm Knee Scoring Scale (LKSS), Knee injury and Osteoarthritis Outcome Score (KOOS) and postoperative complications. STATA 13.0 software was applied for meta-analysis. RESULT: Six randomized controlled trials (RCTs) were conducted, with 900 patients included. The present study revealed that there were significant differences between the two groups regarding the VAS at two months, as well as, WOMAC and range of motion. No significant differences were found in terms of LKSS, KOOS or postoperative complications. LIMITATIONS: (1) Only 6 RCTs were included in our meta-analysis and the sample sizes were small; (2) The follow-up period was too short in some included studies. Long-term follow-up studies should be conducted in the future; (3) Heterogeneity among the included studies was unavoidable due to different grade of degenerative meniscal tear and program of exercise. Heterogeneity was also caused by a variety of other factors. (4) Publication bias that came from the process of literature searching was unavoidable and was hard to overcome. (5) There are many other words which could yielded more studies (Ex. physiotherapy, physical therapy modalities, exercise therapy, rehabilitation, knee, placebo, groups, tibial meniscus, meniscus, arthroscopy, meniscectomy, partial meniscectomy, randomized controlled trial, controlled clinical trial, randomized, systematic review, and meta-analysis). Implications of key findings: This meta-analysis suggests that doctors can choose arthroscopic partial meniscectomy combined with medical exercise therapy for the treatment of degenerative meniscal tear. CONCLUSION: Arthroscopic partial meniscectomy combined with medical exercise therapy is effective in reducing pain and improving range of motion in the early postoperative period. Therefore, arthroscopic partial meniscectomy combined with medical exercise therapy may be recommended for the treatment of degenerative meniscal tear. Further research is necessary to determine the type, frequency, and duration of the best exercise program. Systematic review registration number: Reviewregistry884.

Data of feather recovering performance of birds and micro structure of pigeons' feathers.

Data is presented to explain why birds can recover their ruffled feather vanes by shaking wings and preening feathers with the beak [1]. Presented data includes the SEM microscopic images of rachis, barbs and barbules of pigeon's feather and the images recording the experiments of observing and mimicking the recovering performance of pigeons. Besides, based on the measurement and observation of the micro structure of feathers, the mechanical models of barbules were developed to better understand the wings performance. These high-quality images and models could be used for future research on feathers. Data helps to better understand the micro structure of feathers and the reason birds can fly. Data also support bioinspired mechanical structure development, especially for flapping robot development.

Mechanical Properties and Microstructures of Laser-TIG Welded ME21 Rare Earth Mg Alloy.

The microstructural and mechanical properties of laser-tungsten inert gas (TIG) hybrid welding of Mg alloy sheets for automobiles are investigated in the present work, including AZ31 and ME21, AZ31 and AZ31, ME21 and ME21, and corresponding comparisons were carried out. The results show that columnar crystals appear in the ME21/ME21 and ME21/AZ31 heat-affected zones, and no columnar crystals formed in the AZ31/AZ31 fusion zone under a constant heat ratio of arc to laser. Heat accumulation in a narrow area and the undercooling degree are the two main factors for the formation of columnar crystal. The ME21/ME21 joint has a tensile strength of up to 185.2 MPa, which is about 81.8% of that of the ME21 base metal (BM-ME21). The tensile strength of the ME21/AZ31 joint (158.8 MPa) is lower than that of the ME21/ME21 joint. The fracture of the ME21/ME21 and ME21/AZ31 joints occurs at the junction of the columnar crystal and the heat-affected zone. The microhardness of the ME21/AZ31 joint presents a low-high-low-high trend from BE-ME21 to BE-AZ31, and the distribution of the ME21/AZ31 welded joint microhardness in the cross-section presents a low-high-low trend. The ME21/ME21 weld seam is composed of an AlCe3 intermetallic compound, Mn particles, and α-Mg, and the ME21/AZ31 weld seam is composed of a α-Mg, Mg17Al12, and AlCe3 intermetallic compound.

Combined use of Serum miR-338-3p, Cartilage Oligomeric Matrix Protein and Chondroitin Sulfate-846 in the Early Diagnosis of Knee Osteoarthritis.

BACKGROUND: In this study, the serum levels of miR-338-3p, COMP, and CS-846 were detected in the patients with KOA and healthy controls, to explore the value of miR-338-3p, COMP, and CS-846 in the early diagnosis of KOA. METHODS: Real-time PCR was carried out to evaluate the level of miR-338-3p in KOA patients and healthy controls. Spearman's correlation coefficient was performed to examine the correlation between the expression of miR-338-3p, COMP, and CS-846. Receiver operating characteristic (ROC) curves were carried out to evaluate the diagnostic values of miR-338-3p, COMP, and CS-846 for KOA patients. RESULTS: In the current study, we first demonstrated that serum miR-338-3p, COMP, and CS-846 levels were increased in KOA patients compared to healthy controls. Moreover, the increase of miR-338-3p, COMP, and CS-846 levels positively correlated with VAS scores and joint space narrowing, suggesting miR-338-3p positively correlated with comprehensive disease severity. In addition, miR-338-3p, COMP, and CS-846 could be used as an independent biomarker for KOA patients. More importantly, combined use of miR-338-3p, COMP, and CS-846 demonstrates a higher diagnostic value with an AUC 0.926 for KOA patients. CONCLUSIONS: The combination of miR-338-3p, COMP, and CS-846 demonstrated higher diagnostic value for KOA patients, indicating their combination as novel and promising biomarkers for diagnosis and disease severity of KOA.

TGF­ß1 promotes the osteoinduction of human osteoblasts via the PI3K/AKT/mTOR/S6K1 signalling pathway.

Transforming growth factor ß1 (TGF­ß1) has been suggested to be a candidate cytokine in the field of bone tissue engineering. Cytokines serve important roles in tissue engineering, particularly in the repair of bone damage; however, the underlying molecular mechanisms remain unclear. In the present study, the effects of TGF­ß1 on the osteogenesis and motility of hFOB1.19 human osteoblasts were demonstrated via the phenotype and gene expression of cells. Additionally, the role of the phosphatidylinositol 3­kinase/protein kinase B/mammalian target of rapamycin/S6 kinase 1 (PI3K/AKT/mTOR/S6K1) signalling pathway in the effects of TGF­ß1 on osteoblasts was investigated. It was demonstrated using Cell Counting Kit­8 and flow cytometry assays that the proliferation of human osteoblasts was promoted by 1 ng/ml TGF­ß1. In addition, alkaline phosphatase activity, Alizarin red staining, scratch­wound and Transwell assays were conducted. It was revealed that osteogenesis and the migration of cells were regulated by TGF­ß1 via the upregulation of osteogenic and migration­associated genes. Alterations in the expression of osteogenesis­ and migration­associated genes were evaluated following pre­treatment with a PI3K/AKT inhibitor (LY294002) and an mTOR/S6K1 inhibitor (rapamycin), with or without TGF­ß1. The results indicated that TGF­ß1 affected the osteogenesis and mineralisation of osteoblasts via the PI3K/AKT signalling pathway. Furthermore, TGF­ß1 exhibited effects on mTOR/S6K1 downstream of PI3K/AKT. The present study demonstrated that TGF­ß1 promoted the proliferation, differentiation and migration of human hFOB1.19 osteoblasts, and revealed that TGF­ß1 affected the biological activity of osteoblasts via the PI3K/AKT/mTOR/S6K1 signalling pathway. Our findings may provide novel insight to aid the development of bone tissue engineering methods for the treatment of bone injury.

Ion channel functional protein kinase TRPM7 regulates Mg ions to promote the osteoinduction of human osteoblast via PI3K pathway: In vitro simulation of the bone-repairing effect of Mg-based alloy implant.

Mg-based alloys, as the potential orthopaedic implant, can self-degrade to avoid second operation for its remove, and enable to promote bone repair; however, the underlying molecular mechanisms remain unclear. In the present study, we examined the effect of Mg ions on osteogenesis, chemotaxis and anti-alkaline stress in hFOB1.19 human osteoblast cells to simulate bone-repairing effect of a biodegradable Mg-based alloy implant in vitro, and explored the regulatory role of the transient receptor potential melastatin 7 (TRPM7)/phosphoinositide 3-kinase (PI3K) signalling pathway in the process of Mg ion-induced bone repair by knockdown of TRPM7 and antagonizing PI3K activity. Results indicate that Mg ions up-regulated the expression of Runx2 and alkaline phosphatase (ALP) through TRPM7/PI3K signalling pathway, which could significantly enhance the osteogenic activity of human osteoblasts. Furthermore, the expression levels of MMP2, MMP9 and vascular endothelial growth factor (VEGF) were increased by TRPM7/PI3K signalling pathway, which recruits osteoblasts from low- to high-Mg ion environments by inducing cell migration. Although an alkaline environment has antibacterial effects, alkaline stress can cause cytotoxicity and induce cell death. Finally, we found that Mg ions could activate PI3K phosphorylation to promote cell growth and survival, protecting cells against the alkaline-stress-induced cytotoxicity caused by the degradation of Mg-based alloy implants. Our study not only revealed the molecular mechanism of Mg in promoting bone repair but also explained the protective effects of Mg ions on osteoblasts in an alkaline environment, which provides a theoretical basis and new directions for the application of Mg-based alloy implant material in orthopaedics fixations and osteosarcoma treatment. STATEMENTS OF SIGNIFICANCE: As a potential biomaterial for orthopaedic implant, biodegradable magnesium has several advantages including self-degradation and bone repair promotion; however, the underlying mechanisms and effective concentration by which molecular regulates the bone repair remain unclear. The present study revealed that Mg ion and its effective concentration for activating PI3K phosphorylation via TRPM7, which causes three processes affecting bone repair, namely, osteoblast recruitment, osteogenesis and resistance to alkaline stress in human osteoblast. Therefore, our results have provided insight into the underlying molecular biological basis, and guidance for manipulating degradation rate, such as surface modification, of orthopaedic Mg-based implants.

Efficacy and safety of mildronate for acute ischemic stroke: a randomized, double-blind, active-controlled phase II multicenter trial.

BACKGROUND AND OBJECTIVE: Mildronate, an inhibitor of carnitine-dependent metabolism, is considered to be an anti-ischemic drug. This study is designed to evaluate the efficacy and safety of mildronate injection in treating acute ischemic stroke. METHODS: We performed a randomized, double-blind, multicenter clinical study of mildronate injection for treating acute cerebral infarction. 113 patients in the experimental group received mildronate injection, and 114 patients in the active-control group received cinepazide injection. In addition, both groups were given aspirin as a basic treatment. Modified Rankin Scale (mRS) score was performed at 2 weeks and 3 months after treatment. National Institutes of Health Stroke Scale (NIHSS) score and Barthel Index (BI) score were performed at 2 weeks after treatment, and then vital signs and adverse events were evaluated. RESULTS: A total of 227 patients were randomized to treatment (n = 113, mildronate; n = 114, active-control). After 3 months, there was no significant difference for the primary endpoint between groups categorized in terms of mRS scores of 0-1 and 0-2 (p = 0.52 and p = 0.07, respectively). There were also no significant differences for the secondary endpoint between groups categorized in terms of NIHSS scores of >5 and >8 (p = 0.98 and p = 0.97, respectively) or BI scores of >75 and >95 (p = 0.49 and p = 0.47, respectively) at 15 days. The incidence of serious adverse events was similar between the two groups. CONCLUSION: Mildronate injection is as effective and safe as cinepazide injection in treating acute cerebral infarction.