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The existing theory and techniques of wireless communication anti-jamming have reached their performance limit recently. With this focus, by leveraging the inherent characteristics of wireless communication and referring to the principle of cyberspace endogenous security, this paper investigates the core issues of endogenous security in the electromagnetic space, namely, endogenous anti-jamming (EAJ), which can defend against unknown electromagnetic attacks effectively. Specifically, the subspace method is first adopted to establish the unified framework for the conventional spread-spectrum, intelligent, and endogenous anti-jamming, in which both the intrinsic development law of each technique and the internal logic between them are revealed. Then, the fundamental concept, key techniques, and development suggestions of wireless communication “N + 1 dimensionality” endogenous anti-jamming are proposed to seek a disruptive breakthrough.

Rheumatoid arthritis (RA) is a systemic autoimmune disease characterized by chronic inflammation of the joints and bone destruction. Because of systemic administration and poor targeting, traditional anti‐rheumatic drugs have unsatisfactory treatment efficacy and strong side effects, including myelosuppression, liver or kidney function damage, and malignant tumors. Consequently, mesenchymal stem cells (MSCs)‐involved therapy is proposed for RA therapy as a benefit of their immunosuppressive and tissue‐repairing effects. This review summarizes the progress of MSCs‐involved RA therapy through suppressing inflammation and promoting tissue regeneration and predicts their potential clinical application. [ABSTRACT FROM AUTHOR]

As an irreplaceable ecological barrier, an ecological conservation developing area (ECDA) is vital for the integrated construction of urban and rural areas and the optimization and adjustment of industrial structures. However, few empirical studies have been conducted on the spatiotemporal variations of agricultural green development (AGD) in the ECDAs of large cities. Based on the green agricultural traits of Beijing and the accessible data, we evaluated the AGD and analyzed its spatial and temporal heterogeneity in Beijing's ECDAs by constructing a framework with 13 indicators. The results stated that energy consumption is a vital factor in green agriculture production and that the agricultural output value per unit of arable land area is the key to green agricultural revenue. From 2006 to 2016, the AGD index of the ECDA had an increasing trend, until 2012 when it followed a decreasing tendency. The AGD index of the northern region was higher than in the southern ECDA. The obstacle degree model was used to verify the AGD limiting factors, where poor infrastructure, slow agritourism, low labor productivity, and low resource use efficiency varied by districts in the ECDA. Given these findings, our study is conducive to AGD evaluation at the district (county) level for the ECDAs of large cities and provides important policy implications. [ABSTRACT FROM AUTHOR]

Reconfigurable intelligent surface (RIS)-assisted unmanned aerial vehicles (UAV) have been extensively studied on the Internet of Things (IoT) systems to improve communication performance. In this paper, we aimed to counter simultaneous jamming and eavesdropping attacks by jointly designing an active beamforming vector at the base station (BS) and reflect phase shifts at the RIS. Specifically, considering imperfect angular channel state information (CSI), the sum secrecy rate maximization problem in the worst case could be formulated, which is NP-hard and non-convex. To address this problem, we improved the robust enhanced signal-to-leakage-and-noise ratio (E-SLNR) beamforming to reduce the computational complexity and mitigate the impact of interference, eavesdropping and jamming. Furthermore, a genetic algorithm with a tabu search (GA-TS) method was proposed to efficiently obtain an approximate optimal solution. The simulation results demonstrated that the proposed GA-TS method converged faster with better results than conventional GA, while the proposed robust scheme could achieve higher sum secrecy rates than the zero-forcing (ZF) and SLNR schemes. [ABSTRACT FROM AUTHOR]

The development of the financial industry directly affects the sustainable competitiveness of a city and even an economic region, and the development of urban finance helps to enhance the sustainable competitiveness of a city. This paper firstly reviews the relevant theories of sustainable urban competitiveness and explains the impact mechanism of financial development on sustainable urban competitiveness in developing regions. It then draws on the data of 17 prefecture-level cities in Central China from 2006 to 2020. It uses quantitative research methods, such as principal component analysis and regression analysis, to analyse and study the factors of financial development that influence sustainable urban competitiveness, thus realising the research purpose of enhancing sustainable urban competitiveness. After an in-depth analysis, the paper draws the following conclusions: (1) financial development is conducive to improving the sustainable competitiveness of a city in developing regions; and (2) the local government should focus not only on expanding the scale of financial development, but also on the quality of financial development, adjusting the financial structure, improving financial efficiency, and actively promoting the opening of financial markets and innovation of financial products. [ABSTRACT FROM AUTHOR]

Transplantation of allogeneic adult spinal cord tissues (aSCTs) to replace the injured spinal cord, serves as a promising strategy in complete spinal cord injury (SCI) repair. However, in addition to allograft immune rejection, damage-associated molecular pattern (DAMP)-mediated inflammatory microenvironments greatly impair the survival and function of transplants. In this study, we aimed to regulate the immune microenvironment after aSCT implantation by developing a functional hybrid gelatin and hyaluronic acid hydrogel (F-G/H) modified with cationic polymers and anti-inflammatory cytokines that can gelatinize at both ends of the aSCT to glue the grafts for perfect matching at defects. The F-G/H hydrogel exhibited the capacities of DAMP scavenging, sustainably released anti-inflammatory cytokines, and reduced lymphocyte accumulation, thereby modulating the immune response and enhancing the survival and function of aSCTs. When the hydrogel was used in combination with a systemic immunosuppressive drug treatment, the locomotor functions of SCI rats were significantly improved after aSCTs and F-G/H transplantation. This biomaterial-based immunomodulatory strategy may provide the potential for spinal cord graft replacement for treating SCI. In this study, we aimed to regulate the immune microenvironment by developing a functional hybrid gelatin and hyaluronic acid hydrogel (F-G/H) modified with cationic polymers and anti-inflammatory cytokines that can gelatinize at both ends of the aSCT to glue the grafts for perfect matching at defects. We found that with the treatment of F-G/H hydrogel, the aSCT survival and function was significantly improved, as a result of reducing recruitment and activation of immune cells through TLR- and ST-2- related signaling. With the combination of immunosuppressive drug treatment, the locomotor functions of SCI rats were significantly improved after aSCTs and F-G/H transplantation. Findings from this work suggest the potential application of the F-G/H as a biomaterial-based immunoregulatory strategy for improving the therapeutic efficiency of the transplanted spinal cord graft for spinal cord injury repair. [Display omitted] [ABSTRACT FROM AUTHOR]

Wireless communications are increasingly vulnerable to simultaneous jamming and eavesdropping attacks due to the inherent broadcast nature of wireless channels. With this focus, due to the potential of reconfigurable intelligent surface (RIS) in substantially saving power consumption and boosting information security, this paper is the first work to investigate the effect of the RIS-assisted wireless transmitter in improving both the spectrum efficiency and the security of multi-user cellular network. Specifically, with the imperfect angular channel state information (CSI), we aim to address the worst-case sum rate maximization problem by jointly designing the receive decoder at the users, both the digital precoder and the artificial noise (AN) at the base station (BS), and the analog precoder at the RIS, while meeting the minimum achievable rate constraint, the maximum wiretap rate requirement, and the maximum power constraint. To address the non-convexity of the formulated problem, we first propose an alternative optimization (AO) method to obtain an efficient solution. In particular, a heuristic scheme is proposed to convert the imperfect angular CSI into a robust one and facilitate the developing a closed-form solution to the receive decoder. Then, after reformulating the original problem into a tractable one by exploiting the majorization-minimization (MM) method, the digital precoder and AN can be addressed by the quadratically constrained quadratic programming (QCQP), and the RIS-aided analog precoder is solved by the proposed price mechanism-based Riemannian manifold optimization (RMO). To further reduce the computational complexity of the proposed AO method and gain more insights, we develop a low-complexity monotonic optimization algorithm combined with the dual method (MO-dual) to identify the closed-form solution. Numerical simulations using realistic RIS and communication models demonstrate the superiority and validity of our proposed schemes over the existing benchmark schemes. [ABSTRACT FROM AUTHOR]

This paper utilizes a reconfigurable intelligent surface (RIS) to enhance the anti-jamming performance of wireless communications, due to its powerful capability of constructing smart and reconfigurable radio environment. In order to establish the practical interactions between the base station (BS) and the jammer, a Bayesian Stackelberg game is formulated, where the BS is the leader and the jammer acts as the follower. Specifically, with the help of a RIS-assisted transmitter, the BS attempts to reliably convey information to users with maximum utilities, whereas the smart jammer tries to interfere the signal reception of users with desired energy efficiency (EE) threshold. Since the BS and the jammer are not cooperative parties, the practical assumption that neither side can obtain the other's strategies is adopted in the proposed game, and the angular information based imperfect channel state information (CSI) is also considered. After tackling the practical assumption by using Cauchy-Schwarz inequality and the imperfect angular information by using the discretization method, the closed-form solution of both sides can be obtained via the duality optimization theory, which constitutes the unique Stackelberg equilibrium (SE). Numerical results demonstrate the superiority and validity of our proposed robust schemes over the existing approaches. [ABSTRACT FROM AUTHOR]

The integration of aerial platforms to provide ubiquitous coverage and connectivity for densely deployed terrestrial networks is expected to be a reality in the emerging sixth-generation networks. Energy-effificient and secure transmission designs are two important components for integrated terrestrial-aerial networks (ITAN). Inlight of the potential of reconfigurable intelligent surface (RIS) for significantly reducing the system power consumption and boosting information security, this paper proposes a multi-layer RIS-assisted secure ITAN architecture to defend against simultaneous jamming and eavesdropping attacks, and investigates energy-efficient hybrid beamforming for it. Specifically, with the availability of imperfect angular channel state information (CSI), we propose a block coordinate descent (BCD) framework for the joint optimization of the user’s received decoder, the terrestrial and aerial digital precoder, and the multi-layer RIS analog precoder to maximize the system energy efficiency (EE) performance. For the design of the received decoder, a heuristic beamforming scheme is proposed to convert the worst-case design problem into a min-max one and facilitate the developing a closed-form solution. For the design of the digital precoder, we propose an iterative sequential convex approximation approach via capitalizing the auxiliary variables and first-order Taylor series expansion. Finally, a monotonic vertex-update algorithm with a penalty convex-concave procedure (P-CCP) is proposed to obtain the analog precoder with satisfactory performance. Numerical results show the superiority and effectiveness of the proposed optimization framework and architecture over various benchmark schemes. [ABSTRACT FROM AUTHOR]

Both the jammer and the eavesdropper pose severe threat to wireless communications due to the broadcast nature of wireless channels. In this paper, an intelligent reflecting surface (IRS) assisted secure communication system is considered, where a base station (BS) wishes to reliably convey information to a user, in the presence of both a jammer and an eavesdropper whose transmit informations are not completely known. Specifically, with the imperfect third-party node's channel state information (CSI) and no knowledge of the jammer's transmit beamforming, we aim to maximize the system achievable rate by jointly designing the BS's transmit beamforming and the IRS's reflect beamforming, while limiting the information leakage to the potential eavesdropper. Due to the non-convexity and intractability of the original problem induced by the incompleted information, we utilize the auxiliary variables, Cauchy-Schwarz inequality, and General Sign-Definiteness transformation to convert the original optimization problem into a tractable convex optimization problem, and then obtain the high-quality optimal solution by using the successive convex approximation and penalty convex concave procedure. Numerical simulations demonstrate the superiority of our proposed optimization algorithm compared with existing approaches, and also reveal the impact of key parameters on the achievable system performance. [ABSTRACT FROM AUTHOR]

A facile and efficient strategy is proposed to prepare Ag-nanoparticle-embedded magnetic metal–organic frameworks [MOFs; Fe3O4@MIL-100-(Fe)/Ag]. The as-prepared nanocomposites are regular spherical and contain a Fe3O4 core with an average diameter of 400 nm, which make them exhibit good magnetic properties and can be conveniently separated. A 50 nm MIL-100-(Fe) MOF shell is uniformly coated on the Fe3O4 core and loads well-dispersed 2.0 ± 0.8 nm Ag nanoparticles in their pores, which make the nanocomposites have excellent catalytic and recyclable performances for catalytic reduction of 4-nitrophenol. This production strategy is highly efficient and can be used to fabricate other similar porous nanocomposites. [ABSTRACT FROM AUTHOR]

The purpose of this research is to assess the feasibility of poly(lactic-co-glycolic) acid (PLGA) incorporating gelatin microspheres (PLGA/GMs scaffold) for enhancing osteogenesis in vitro and at a radius defect of rabbits after X-ray radiation in vivo. After incorporating gelatin microspheres, PLGA scaffold demonstrated improved mechanical properties. Moreover, a sustained release property of recombinant human bone morphogenetic protein-2 (BMP-2) was achieved in BMP-2-releasing PLGA/GMs scaffold. BMP-2-releasing PLGA/GMs scaffold also enhanced proliferation and osteogenesis of rabbit bone mesenchymal stem cells (BMSCs) in vitro, indicating the bioactivity of BMP-2. After finishing X-ray radiation of the radius bone, 20-mm radius bone defects were generated, followed by being implanted with BMP-2-releasing PLGA/GMs scaffolds with or without bone marrow. Both PLGA/GMs scaffolds containing bone marrow or BMP-2 showed more obvious enhancement for bone regeneration than the empty scaffolds (control) at the radius defect. In the X-ray radiated groups, however, the bone regeneration was inhibited either with bone marrow or BMP-2. When combined with bone marrow, the BMP-2 showed significantly high osteogenic effect, regardless of X-ray radiation. It is considered that it is a promising way to repair bone defects even after X-ray radiation by a combination of bone marrow with the BMP-2-releasing PLGA/GMs scaffold. [ABSTRACT FROM AUTHOR]

It has been demonstrated that microRNAs (miRNAs) may contribute to tumorigenesis and tumor growth in osteosarcoma (OS), which is a primary malignant tumor of bone frequently diagnosed in adolescents and young people. The purpose of our investigation was to evaluate the functional relevance of miR‐377 in OS and to investigate whether the mechanism was related to the histone acetyltransferase 1 (HAT1)‐mediated Wnt signaling pathway. By screening differentially expressed genes in microarray GSE47572, HAT1 was found to be a candidate gene of interest. Besides, the regulatory miRNA (miR‐377) of HAT1 was also selected. The interaction among miR‐377, HAT1, and the Wnt signaling pathway was evaluated. In addition, the miR‐377 expression was altered in OS cells (U‐2OS and SOSP‐9607) to assess the in vitro cell apoptosis and the in vivo tumor growth. OS tissues presented elevated HAT1 expression and decreased miR‐377 expression. A putative miR‐377 binding site in HAT1 3′‐UTR HAT1 was verified. Cells with miR‐377 overexpression or HAT1 silencing were observed to exhibit reduced HAT1 expression and promoted apoptosis, accompanied by blockade of Wnt signaling. Moreover, the in vivo experiment revealed that miR‐377 overexpression or HAT1 silencing inhibited tumor growth and reduced tumor size in nude mice. Taken together, our results conclude that miR‐377 may promote OS cell apoptosis through inactivation of the HAT1‐mediated Wnt signaling pathway, highlighting the potential therapeutic effect of miR‐377 on OS treatment. [ABSTRACT FROM AUTHOR]

During the human bone formation, the event of osteogenic differentiation of human bone mesenchymal stem cells (hBMSCs) is vital, and recent evidence has emphasized the important role of microRNAs (miRNAs) in osteogenic differentiation of hBMSCs. This study aims to examine the potential effects of miR‐200c in osteogenic differentiation of hBMSCs and understand their underlying mechanisms. HBMSCs were obtained via human bone marrow. During osteogenic induction and differentiation, cells were transfected with different plasmids with the intention of investigating the roles of miR‐200c on osteogenic differentiation, calcium salt deposition, alkaline‐phosphatase (ALP) activity, mineralized nodule formation, osteocalcin (OCN) content, and proliferation of osteoblasts. Following transfection, dual luciferase reporter gene assay was conducted so as to explore the correlation between miR‐200c and Myd88. Moreover, the AKT/β‐Catenin signaling pathway was blocked with an AKT/β‐Catenin inhibitor, AKTi, to investigate its involvement. The hBMSCs were successfully isolated from human bone marrow. Myd88 was determined as a target gene of miR‐200c. Gain and loss‐of‐function assays confirmed that overexpression of miR‐200c, or silencing of Myd88 promoted osteogenic differentiation, increased calcium salt deposition, ALP activity, mineralized nodule formation, and enhanced the proliferation of osteoblasts following osteogenic differentiation of hBMSCs. Meanwhile, the downregulation of miR‐200c has been shown to have the opposite effect. Furthermore, these findings showed that the miR‐200c overexpression activated the AKT/β‐Catenin signaling pathway by targeting Myd88. To sum up, the miR‐200c upregulation induces osteogenic differentiation of hBMSCs by activating the AKT/β‐Catenin signaling pathway via the inhibition of Myd88, providing a target for treatment of bone repair. [ABSTRACT FROM AUTHOR]

Osteosarcoma (OS), as the most frequent primary malignancy of bone, is characterized by the presence of malignant mesenchymal cells. In the current study, our aim was to explore the possible effects Fos‐like antigen‐1 (FOSL1) had on the silencing regarding OS cell proliferation, invasion, and migration through the activation of the extracellular‐signal‐regulated kinase (ERK)/activator protein‐1 (AP‐1) signaling pathway. After the collection of OS on top of already having the adjacent normal tissue samples, the protein positive expression rate of FOSL1 was then measured by implementing the use of immunohistochemistry and discovered that FOSL1 was robustly expressed in OS. Later, to better grasp the impact FOSL1 projects on OS and its underlying mechanism, we determined the OS related genes as well as the ERK/AP‐1 signaling pathway related genes expression by using a reverse‐transcription quantitative polymerase chain reaction and western blot assay techniques. The results of the aforementioned two experiments revealed that the FOSL1 depletion had downregulated the expression of OS related genes by simultaneously downregulating the ERK/AP‐1 signaling pathway. Moreover, cell proliferation, cycle, apoptosis, invasion, and migration of FOS1 were all tested by using a cell counting kit‐8 assay, flow cytometry, Transwell assay, and scratch test, and these results presented that silencing of the FOSL1 gene inhibited OS cell proliferation, invasion, and migration. Our findings revealed a novel mechanism by which FOSL1 depletion played a significantly negative role in the OS progression through the regulation of the ERK/AP‐1 signaling pathway. Functional suppression of FOSL1 might be a future therapeutic strategy regarding OS. Our findings revealed a novel mechanism by which Fos‐like antigen‐1 (FOS1) depletion played a significantly negative role in the osteosarcoma (OS) progression through the regulation of the extracellular‐signal‐regulated kinase/activator protein‐1 signaling pathway. Functional suppression of FOSL1 might be a future therapeutic strategy regarding OS. [ABSTRACT FROM AUTHOR]

The aim was to explore the effect of lateral recess decompression by percutaneous transforaminal endoscopic spine system (Tessys) technique combined with percutaneous transforaminal endoscopic discectomy (PTED) on pain medium, nerve function and stress response in patients suffering from contralateral symptoms of lumbar disc herniation. A total of 96 patients with contralateral symptoms of lumbar disc herniation treated in our hospital from February 2015 to April 2017 were randomly divided into control group and study group, with 48 cases in each group. The control group underwent PTED, and the study group underwent lateral recess decompression by Tessys technique combined with PTED. The visual analogue scale (VSA) score and Japanese Orthopaedic Association (JOA) score before surgery and 3 months after surgery were compared between the two groups. The levels of serum pain medium (prostaglandin E2 (PGE2), histamine (HA), 5-hydroxytryptamine (5-HT)) and oxidative stress indexes (malondialdehyde (MDA), myeloperoxidase (MPO), superoxide dismutase (SOD), total antioxidant capacity (TAC)) before surgery and 7 days after surgery were compared. The clinical efficacy of the two groups was compared at 1 month after treatment. One month after treatment, the excellent and good rate in the study group was significantly higher than that in the control group (85.4% vs 56.3%; P < 0.05). There was no significant difference between VAS and JOA score in the two groups preoperatively (P > 0.05). At 3 months after surgery, the VAS score in the study group was significantly lower than that in the control group (P < 0.05), and the JOA score in the study group was significantly higher than that in the control group (P < 0.05). There was no significant difference in serum PGE2, HA and 5-HT levels between the two groups preoperatively (P > 0.05). At 7 days after surgery, the serum PGE2, HA and 5-HT levels in the study group were significantly lower than those in the control group (P < 0.05). Preoperatively, the levels of serum MDA, MPO, SOD and TAC were not significantly different between the two groups (P > 0.05). On the seventh day after surgery, the levels of serum MDA and MPO in the study group were significantly lower than those in the control group (P < 0.05), and the levels of SOD and TAC were significantly higher than those in the control group (P < 0.05). In conclusion, the combined therapy of lateral recess decompression by Tessys technique and PTED in patients suffering from contralateral symptoms of lumbar disc herniation has a definite clinical effect, which can significantly alleviate the symptoms of low back pain and motor nerve function and reduce the contents of serum pain medium and the levels of oxidative stress. It is worthy of clinical promotion. [ABSTRACT FROM AUTHOR]

The aim of this present work is to investigate the interaction between amifostine and human serum albumin (HSA) in simulated physiological conditions by spectroscopic methods to reveal potential toxic effects of the drug. The results reflected that amifostine caused fluorescence quenching of HSA through a static quenching process, which was further confirmed by the electrochemical experiments. The binding constants at 290, 297 and 304 K were obtained as 2.53 × 105/M, 8.13 × 104/M and 3.59 × 104/M, respectively. There may be one binding site of amifostine on HSA. The thermodynamic parameters indicated that the interaction between amifostine and HSA was driven mainly by hydrogen bonding and electrostatic forces. Synchronous fluorescence spectra, circular dichroism and Fourier transform infrared spectroscopy results showed amifostine binding slightly changed the conformation of HSA with secondary structural content changes. Förster resonance energy transfer study revealed high possibility of energy transfer with amifostine-Trp-214 distance of 3.48 nm. The results of the present study may provide valuable information for studying the distribution, toxicological and pharmacological mechanisms of amifostine in vivo. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Robustness and vulnerability are important evaluation criteria for structural safety to improve progressive collapse resistance. Modeling rapid evaluation on important elements in the conceptual analysis stage is an essential and efficient way to ensure the robustness of a design. This paper proposes an evaluation method for element importance by using structural strain energy, which can reflect the influence of geometric topology and external load distribution on the structural safety status simultaneously. Three simple planar trusses are chosen to clarify the proposed method. Moreover, the influences of geometric topology, boundary condition, stiffness distribution and load distribution on the element importance are investigated. This evaluation method also extends to the two spatial truss structures, regular quadrangular pyramid grid structures and chessboard-shaped pyramid grid structures. The distribution characteristics of important elements are obtained. This work defines the element importance distribution law of typical structures. It provides a method for rapid robustness analysis of general truss structures, which can be effectively integrated into the existing analysis platform. [ABSTRACT FROM AUTHOR]

Osteosarcoma (OS) is the most common primary malignancy of bone and is characterized by a high malignant and metastatic potential. Microarray-based differentially expressed gene screening determined RAC2 as the candidate gene related to OS. Highly expressed RAC2 and activated Wnt signaling pathway were determined in OS tissues using reverse transcription quantitative polymerase chain reaction (RT-qPCR) and Western blot analysis. The OS cells were transfected with siRNA-RAC2 or treated with BIO (activator of Wnt pathway), whereby the effects of siRNA-RAC2 on cell proliferation, invasion, cycle and apoptosis were analyzed by CCK-8, Transwell assay and flow cytometry. The mRNA and protein levels of RAC2 and the Wnt signaling pathway-, proliferation- and apoptosis-related genes in OS cells were determined by RT-qPCR and Western blot assay. Importantly, siRNA-mediated RAC2 silencing inhibited the activation of the Wnt signaling pathway in OS. siRNA-RAC2 inhibited the proliferation and invasion, while impeded OS cell cycle progression and facilitated cell apoptosis. However, activation of Wnt signaling pathway reversed the effects of siRNA-RAC2. Finally, orthotopic xenograft OS mouse model confirmed the in vivo anti-tumor effects by silencing RAC2. Taken together, RAC2 gene silencing could suppress OS progression. The mechanism was obtained by inhibiting the activation of the Wnt signaling pathway. [ABSTRACT FROM AUTHOR]

The therapeutic effect of osteosarcoma (OS) has not made extraordinary progress in the past few decades. Oxaliplatin (OXA) is a widely used clinical anti-tumor drug. Recent studies have shown that OXA can trigger anti-tumor immunity by inducing immunogenic death (ICD). Alendronate (ALN) has been used to threaten the skeletal system tumors because of the unique bone affinity and the ability to inhibit bone destruction. In this study, we co-loaded OXA and ALN on mPEG45-PLV19 thermo-sensitive hydrogel to perform in situ treatment on the mouse OS model. Slowly released OXA can induce immunogenic death of tumor cells. At the same time, thermo-sensitive hydrogels can induce the accumulation of cytotoxic T lymphocytes. Besides, ALN could synergistically diminish tumors and prevent bone destruction. This system could synergistically inhibit the progression of OS and lung metastasis and has no toxicity to various organs throughout the body., (Copyright © 2020 Sun, Li, Li, Zhang and Zhao.)

The development of effective treatment for the infection and bone defect resulting from advanced osteomyelitis is an urgent task in the orthopedic clinic. To simultaneously address the issues of infection and bone defect, the multifunctional electrospun scaffolds composed of polylactide (PLA), nano-hydroxyapatite- graft -polylactide (nHA- g -PLA), and antibiotic vancomycin (VAN) were developed for the treatment of advanced osteomyelitis in the present study. The composite scaffolds PLA/nHA/VAN could sustainably release VAN and exhibited excellent antibacterial activity toward S. aureus . The rough surface of PLA/nHA/VAN induced by the presence of nHA- g -PLA promoted the adhesion and proliferation of osteoblasts. More interestingly, PLA/nHA/VAN, especially PLA/nHA 10 /VAN 8 , reduced bone infections and boosted bone regeneration at the defect site with better outcomes than other treatment groups. In conclusion, it has been demonstrated to be highly effective for the treatment of osteomyelitis using the scaffolds with sustained release properties, which has great potential for real application in the orthopedic clinic.

In contrast to systemic chemotherapy, the local administration of chemotherapeutics potentially optimizes their accumulation in the tumor tissues and alleviates the associated systemic toxicity. However, the lack of control over the release of encapsulated drugs and their degradation represents a major challenge for local drug delivery systems. In this study, we developed a series of epirubicin (EPI)-loaded poly(ε-caprolactone)/poly(lactide- co -glycolide) (PCL/PLGA) nanofiber capsules with adjustable rates of drug release and degradation for local malignancy chemotherapy. The core-sheath PCL/PLGA nanofiber capsules containing 15.0 or 25.0 wt% of PCL in the sheath and 0, 5.0, or 10.0 wt% of EPI in the core were produced by emulsion electrospinning technology. The EPI release and degradation of the nanofiber capsules could be accelerated by decreasing the PCL content in the sheath. More importantly, the EPI-loaded PCL/PLGA nanofiber capsules effectively inhibited the growth of tumor cells in vitro and in vivo . Moreover, none of the laden nanofiber capsules caused apparent systemic toxicity. Hence, the cytostatic-loaded electrospun polyester nanofiber capsules displayed controlled drug release and degradation, along with satisfactory antitumor properties, indicating their great potential in local malignancy chemotherapy.

Osteosarcoma is the most common type of aggressive bone cancer. Current treatment strategies include surgical resection, radiation, and chemotherapy. Doxorubicin has been widely used as a chemotherapeutic drug to treat osteosarcoma. However, drug resistance has become a challenge to its use. In this study, p53-wild type U2OS and p53-null MG-63 osteosarcoma-derived cells were used to investigate the mechanism of doxorubicin-induced cytotoxicity. In cell viability assays, doxorubicin effectively induced apoptosis in U2OS cells via the p53 signaling pathway, evidenced by elevated PUMA and p21 protein levels and activated caspase 3 cleavage. In contrast, p53-null MG-63 cells were resistant to doxorubicin-induced apoptosis, while exogenous expression of p53 increased drug sensitivity in those cells. The role of TGF-β/Smad3 signaling was investigated by using TGF-β reporter luciferase assays. Doxorubicin was able to induce TGF-β signal transduction without increasing TGF-β production in the presence of p53. Knockdown of Smad3 expression by small hairpin RNA (shRNA) showed that Smad3 was required for p53-mediated TGF-β signaling in response to doxorubicin treatment in U2OS and MG-63 cells. Taken together, these data demonstrate that p53 and TGF-β/Smad3 signaling pathways are both essential for doxorubicin-induced cytotoxicity in osteosarcoma cells.

Purpose: The aim of this study was to investigate the association between osteosarcoma (OS) and Fanconi anemia (FA) related pathways and the molecular mechanisms., Methods: siRNA for Fanconi anemia complementation group D2 (FANCD2) was constructed and transfected into the osteosarcoma cell line MG-63 cells. Expression of TP53INP1, p53, p21, caspase-9, and caspase-3 mRNA in MG-63 cells were examined by real-time fluorescence quantitative PCR, and the protein levels were also determined by western blot., Results: After silence of the FANCD2 gene in MG-63 cells, cell proliferation was inhibited, cell cycle was arrested and cell apoptosis was induced. The apoptosis was mediated by the p53 signaling pathway. After FANCD2 expression was inhibited, TP53INP1 gene expression was up-regulated, phosphorylation of p53 was promoted and the p21 protein was activated, leading to cell cycle arrested in G1, finally resulted in caspase-dependent cell apoptosis., Conclusions: Inhibition of FANCD2 gene expression can induce apoptosis of osteosarcoma cells, which indicated that FANCD2 played an important role in the development of osteosarcoma and it might be a potential target for treatment of osteosarcoma.

Objective: We aimed to compare the clinical outcomes of anterior approaches (anterior cervical corpectomy with fusion, cervical discectomy with fusion) and posterior approaches (laminectomy, laminoplasty) in multilevel cervical spondylotic myelopathy (MCSM) patients using a systematic meta-analysis., Methods: PubMed, Embase, Scopus, and the Cochrane library were searched for literatures up to March 27, 2015 without language restriction. The reference lists of selected articles were also screened. Heterogeneity was identified using Q test and I(2) statistic. A fixed effect model was used for homogeneous data and a random effects model for heterogeneous data. Weighted mean difference (WMD) or odds ratio (OR) with 95% confidence intervals (CIs) were calculated. Subgroup analysis was conducted according to the cause of MCSM., Results: Seventeen articles were selected. Higher post-Japanese Orthopedic Association (JOA, P=0.002) and shorter length of stay (P=0.004) were found in anterior approaches group compared with posterior approaches. Moreover, operation time was shorter (P<0.00001) and neurological recovery rate was higher (P=0.005) in ossification of posterior longitudinal ligament patients underwent posterior approaches. Complication rate of posterior approaches was lower in spinal stenosis subgroup (P<0.0001)., Conclusions: MCSM patients performed anterior approaches showed superior post-JOA and shorten length of stay. However, the outcomes such as operation time and complication rate are associated with the cause of MCSM. Therefore, the favorable surgical strategy for MCSM still needs more studies., (Copyright © 2015 Elsevier B.V. All rights reserved.)