Regenerative medicine strategies for chronic complete spinal cord injury

Spinal cord injury is a condition in which the parenchyma of the spinal cord is damaged by trauma or various diseases.While rapid progress has been made in regenerative medicine for spinal cord injury that was previously untreatable,most research in this field has focused on the early phase of incomplete injury.However,the majority of patients have chronic severe injuries;therefore,treatments for these situations are of fundamental importance.The reason why the treatment of complete spinal cord injury has not been studied is that,unlike in the early stage of incomplete spinal cord injury,there are various inhibitors of neural regeneration.Thus,we assumed that it is difficult to address all conditions with a single treatment in chronic complete spinal cord injury and that a combination of several treatments is essential to target severe pathologies.First,we established a combination therapy of cell transplantation and drug-releasing scaffolds,which contributes to functional recovery after chronic complete transection spinal cord injury,but we found that functional recovery was limited and still needs further investigation.Here,for the further development of the treatment of chronic complete spinal cord injury,we review the necessary approaches to the different pathologies based on our findings and the many studies that have been accumulated to date and discuss,with reference to the literature,which combination of treatments is most effective in achieving functional recovery.

Advances in clinical applications of bioceramics in the new regenerative medicine era

In this editorial,we comment on the hard and soft tissue applications of different ceramic-based scaffolds prepared by different mechanisms such as 3D printing,sol-gel,and electrospinning.The new concept of regenerative medicine relies on biomaterials that can trigger in situ tissue regeneration and stem cell recruitment at the defect site.A large percentage of these biomaterials is ceramic-based as they provide the essential requirements of biomaterial principles such as tailored multisize porosity,antibacterial properties,and angiogenic properties.All these previously mentioned properties put bioceramics on top of the hierarchy of biomaterials utilized to stimulate tissue regeneration in soft and hard tissue wounds.Multiple clinical applications registered the use of these materials in triggering soft tissue regeneration in healthy and diabetic patients such as bioactive glass nanofibers.The results were promising and opened new frontiers for utilizing these materials on a larger scale.The same results were mentioned when using different forms and formulas of bioceramics in hard defect regeneration.Some bioceramics were used in combination with other polymers and biological scaffolds to improve their regenerative and mechanical properties.All this progress will enable a larger scale of patients to receive such services with ease and decrease the financial burden on the government.

Regenerative Braking Energy Recovery System of Metro Train Based on Dual-Mode Power Management

In order to fully utilize the regenerative braking energy of metro trains and stabilize the metro DC traction busbar voltage,a hybrid regenerative braking energy recovery system with a dual-mode power management strategy is proposed.Firstly,the construction of the hybrid regenerative braking energy recovery system is explained.Then,based on the power demand of low-voltage load in metro stations,a dual-mode power management strategy is proposed to allocate the reference power of each system according to the different working conditions,and the control methods of each system are set.Finally,the correctness and effectiveness of the dual-mode strategy are verified through simulation,and the proposed braking energy utilization scheme is compared with other singleform utilization schemes.The results illustrate that the hybrid system with the dual-mode strategy can effectively recycle the regenerative braking energy of metro train and inhibit the busbar voltage fluctuation;the proposed braking energy utilization scheme has certain advantages on energy recovery and DC bus voltage stabilization compared with other single-form schemes;the proposed power management strategy can correctly allocate the reference power of each system with a lower construction cost.

Modified approach of regenerative treatment for distal intrabony defect beneath non-keratinized mucosa at terminal molar:A case report

BACKGROUND Intrabony defects beneath non-keratinized mucosa are frequently observed at the distal site of terminal molars.Consequently,the application of regenerative treatment using the modified wedge-flap technique is considered impractical for these specific dental conditions.CASE SUMMARY This article proposes a modified surgical procedure aimed at exposing the distal intrabony defect by making a vertical incision in the keratinized buccal gingiva.The primary objective is to maintain gingival flap stability,thereby facilitating periodontal regeneration.The described technique was successfully employed in a case involving the left mandibular second molar,which presented with an intrabony defect without keratinized gingiva at the distal site.In this case,an incision was made on the disto-buccal gingival tissue,creating a tunnel-like separation of the distal non-keratinized soft tissue to expose the intrabony defect.Subsequently,bone grafting and guided tissue regeneration surgeries were performed,resulting in satisfactory bone fill at 9 mo postoperatively.CONCLUSION This technique offers a regenerative opportunity for the intrabony defects beneath non-keratinized mucosa and is recommended for further research.

面向RISC-V适配开发的x86 built-in函数转换方法

新兴架构RISC-V的生态建设需要将其他架构函数或软件包向RISC-V架构迁移适配。在研究GCC特定架构适配的built-in函数向RISC-V架构迁移时,提出一套x86到RISC-V的built-in函数转换方法,对于非扩展指令集(属非向量类型)built-in函数,采用RISC-V架构下相同功能的built-in或标准库函数替代;对于SSE扩展指令集built-in函数,建立数据类型映射和向量函数操作映射实现向RISC-V架构向量扩展函数或标准库函数的迁移,其中RVV函数迁移方式占比67%。实验结果表明:方法迁移的程序功能正确,方法有效。本文方法对其他扩展指令集built-in函数的迁移提供了指导,且与现有工作相比,更易扩展、覆盖面更广。

Pitfalls and promises of bile duct alternatives:There is plenty of room in the regenerative surgery

Current abdominal surgery has several approaches for biliary reconstruction.However,the creation of functional and clinically applicable bile duct substitutes still represents an unmet need.In the paper by Miyazawa and colleagues,approaches to the creation of bile duct alternatives were summarized,and the reasons for the lack of development in this area were explained.The history of bile duct surgery since the nineteenth century was also traced,leading to the conclusion that the use of bioabsorbable materials holds promise for the creation of bile duct substitutes in the future.We suggest three ideas that may stimulate progress in the field of bile duct substitute creation.First,a systematic analysis of the causative factors leading to failure or success in the creation of bile duct substitutes may help to develop more effective approaches.Second,the regeneration of a bile duct is delicately balanced between epithelialization and subsequent submucosal maturation within limited time frames,which may be more apparent when using quantitative models to estimate outcomes.Third,the utilization of the organism’s endogenous regeneration abilities may enhance the creation of bile duct substitutes.We are convinced that an interdisciplinary approach,including quantitative methods,machine learning,and deep retrospective analysis of the causes that led to success and failure in studies on the creation of bile duct substitutes,holds great value.Additionally,more attention should be directed towards the balance of epithelialization and submucosal maturation rates,as well as induced angiogenesis.These ideas deserve further investigation to pave the way for bile duct restoration with physiologically relevant outcomes.

Unleashing the healing potential:Exploring next-generation regenerative protein nanoscaffolds for burn wound recovery

Burn injury is a serious public health problem and scientists are continuously aiming to develop promising biomimetic dressings for effective burn wound management.In this study,a greater efficacy in burn wound healing and the associated mechanisms ofα-lactalbumin(ALA)based electrospun nanofibrous scaffolds(ENs)as compared to other regenerative protein scaffolds were established.Bovine serum albumin(BSA),collagen type I(COL),lysozyme(LZM)and ALA were separately blended with poly(ε-caprolactone)(PCL)to fabricate four different composite ENs(LZM/PCL,BSA/PCL,COL/PCL and ALA/PCL ENs).The hydrophilic composite scaffolds exhibited an enhancedwettability and variablemechanical properties.The ALA/PCL ENs demonstrated higher levels of fibroblast proliferation and adhesion than the other composite ENs.As compared to PCL ENs and other composite scaffolds,the ALA/PCL ENs also promoted a better maturity of the regenerative skin tissues and showed a comparable wound healing effect to Collagen sponge^(■)on third-degree burn model.The enhanced wound healing activity of ALA/PCL ENs compared to other ENs could be attributed to their ability to promote serotonin production at wound sites.Collectively,this investigation demonstrated that ALA is a unique protein with a greater potential for burn wound healing as compared to other regenerative proteins when loaded in the nanofibrous scaffolds.

Injectable hydrogel made from antler mesenchyme matrix for regenerative wound healing via creating a fetal-like niche

BACKGROUND Scar formation and loss of cutaneous appendages are the greatest challenges in cutaneous wound healing.Previous studies have indicated that antler reserve mesenchyme(RM)cells and their conditioned medium improved regenerative wound healing with partial recovery of cutaneous appendages.AIM To develop hydrogels from the antler RM matrix(HARM)and evaluate the effect on wound healing.METHODS We prepared the hydrogels from the HARM via enzymatic solubilization with pepsin.Then we investigated the therapeutic effects of HARM on a full-thickness cutaneous wound healing rat model using both local injections surrounding the wound and topical wound application.RESULTS The results showed that HARM accelerated wound healing rate and reduced scar formation.Also,HARM stimulated the regeneration of cutaneous appendages and blood vessels,and reduced collagen fiber aggregation.Further study showed that these functions might be achieved via creating a fetal-like niche at the wound site.The levels of fetal wound healing-related genes,including Collagen III and TGFβ3 treated with HARM were all increased,while the expression levels of Collagen I,TGFβ1,and Engrailed 1 were decreased in the healing.Moreover,the number of stem cells was increased in the fetal-like niche created by HARM,which may contribute to the regeneration of cutaneous appendages.CONCLUSION Overall,we successfully developed an injectable hydrogel made from antler RM matrix for the regenerative repair of full-thickness cutaneous wounds.We uncovered the molecular mechanism of the hydrogels in promoting regenerative wound healing,and thus pave the way for HARM to be developed for the clinic use.

Extracellular vesicles:Emerged as a promising strategy for regenerative medicine

Cell transplantation therapy has certain limitations including immune rejection and limited cell viability,which seriously hinder the transformation of stem cellbased tissue regeneration into clinical practice.Extracellular vesicles(EVs)not only possess the advantages of its derived cells,but also can avoid the risks of cell transplantation.EVs are intelligent and controllable biomaterials that can participate in a variety of physiological and pathological activities,tissue repair and regeneration by transmitting a variety of biological signals,showing great potential in cell-free tissue regeneration.In this review,we summarized the origins and characteristics of EVs,introduced the pivotal role of EVs in diverse tissues regeneration,discussed the underlying mechanisms,prospects,and challenges of EVs.We also pointed out the problems that need to be solved,application directions,and prospects of EVs in the future and shed new light on the novel cell-free strategy for using EVs in the field of regenerative medicine.

A Review of Electromagnetic Energy Regenerative Suspension System&Key Technologies

The active suspension has undoubtedly improved the performance of the vehicle,however,the trend of“lowcarbonization,intelligence,and informationization”in the automotive industry has put forward higher and more urgent requirements for the suspension system.The automotive industry and researchers favor active energy regeneration suspension technology with safety,comfort,and high energy regenerative efficiency.In this paper,we review the research progress of the structure form,optimization method,and control strategy of electromagnetic energy regenerative suspension.Specifically,comparing the pros and cons of the existing technology in solving the contradiction between dynamic performance and energy regeneration.In addition,the development trend of electromagnetic energy regenerative suspension in the field of structure form,optimization method,and control technology prospects.

Regenerative Medicine: A Review of Solutions in the Treatment of Skin Defects

The issue of skin defects is a major concern of almost every trauma surgeon after surgery. Despite numerous conventional methods and introduction of the reconstruction ladder, managing skin defects is still a challenge for the trauma surgeons. In recent years, parallel to the advances in the more conventional methods of skin repair, regenerative medicine has offered new and novel treatments. This article aims to explore these contemporary regenerative solutions as well as to review the conventional methods of treating skin defects.

Regenerative Medicine in Orthopaedics: Microsurgery Achievements for Translational Animal Model

Purpose: Despite many scientific advances, Regenerative Medicine is still in the preclinical stages in many areas. In this article, we intend to discuss the role of microsurgery in the bench-to-bedside transition of such primary findings. Method: By searching the papers related to the history of Regenerative Medicine (RM) and the news of Tissue Engineering (TE) in orthopedics in Pubmed, Scopus, and Google Scholar databases, we accessed a complete archive of various topics related to this field. Result: We first assessed the history and achievements of regenerative medicine, then we realized the importance of translational medical sciences and the role of animal models in this incipient phenomenon. Finally, after mastering the capabilities of microsurgery and the useful contribution of this technique to the advancement of clinical applications of regenerative medicine in various branches such as skin, skeletal system, nerves, and blood vessels, we decided to express the gist of our studies through this article. Conclusion: Considering the widespread use of small animals in regenerative medicine projects and the inevitable role of microsurgery in performing the best intervention on these animal models, the significant progress of regenerative medicine clinical application requires special attention to microsurgery in associated research.

Regenerative peripheral nerve interface prevents neuroma formation after peripheral nerve transection

Neuroma formation after peripheral nerve transection often leads to severe neuropathic pain.Regenerative peripheral nerve interface has been shown to reduce painful neuroma in the clinic.However,no reports have investigated the underlying mechanisms,and no comparative animal studies on regenerative peripheral nerve interface and other means of neuroma prevention have been conducted to date.In this study,we established a rat model of left sciatic nerve transfection,and subsequently interfered with the model using the regenerative peripheral nerve interface or proximal nerve stump implantation inside a fully innervated muscle.Results showed that,compared with rats subjected to nerve stump implantation inside the muscle,rats subjected to regenerative peripheral nerve interface intervention showed greater inhibition of the proliferation of collagenous fibers and irregular regenerated axons,lower expressions of the fibrosis markerα-smooth muscle actin and the inflammatory marker sigma-1 receptor in the proximal nerve stump,lower autophagy behaviors,lower expressions of c-fos and substance P,higher expression of glial cell line-derived neurotrophic factor in the ipsilateral dorsal root ganglia.These findings suggested that regenerative peripheral nerve interface inhibits peripheral nerve injury-induced neuroma formation and neuropathic pain possibly via the upregulation of the expression of glial cell line-derived neurotrophic factor in the dorsal root ganglia and reducing neuroinflammation in the nerve stump.

Energy Management of Networked Smart Railway Stations Considering Regenerative Braking, Energy Storage System, and Photovoltaic Units

The networking of microgrids has received significant attention in the form of a smart grid.In this paper,a set of smart railway stations,which is assumed as microgrids,is connected together.It has been tried to manage the energy exchanged between the networked microgrids to reduce received energy from the utility grid.Also,the operational costs of stations under various conditions decrease by applying the proposed method.The smart railway stations are studied in the presence of photovoltaic(PV)units,energy storage systems(ESSs),and regenerative braking strategies.Studying regenerative braking is one of the essential contributions.Moreover,the stochastic behaviors of the ESS’s initial state of energy and the uncertainty of PV power generation are taken into account through a scenario-based method.The networked microgrid scheme of railway stations(based on coordinated operation and scheduling)and independent operation of railway stations are studied.The proposed method is applied to realistic case studies,including three stations of Line 3 of Tehran Urban and Suburban Railway Operation Company(TUSROC).The rolling stock is simulated in the MATLAB environment.Thus,the coordinated operation of networked microgrids and independent operation of railway stations are optimized in the GAMS environment utilizing mixed-integer linear programming(MILP).

Constructing Built-In Electric Fields with Semiconductor Junctions and Schottky Junctions Based on Mo-MXene/Mo-Metal Sulfides for Electromagnetic Response

The exploration of novel multivariate heterostructures has emerged as a pivotal strategy for developing high-performance electromagnetic wave(EMW)absorption materials.However,the loss mechanism in traditional heterostructures is relatively simple,guided by empirical observations,and is not monotonous.In this work,we presented a novel semiconductor-semiconductor-metal heterostructure sys-tem,Mo-MXene/Mo-metal sulfides(metal=Sn,Fe,Mn,Co,Ni,Zn,and Cu),including semiconductor junctions and Mott-Schottky junctions.By skillfully combining these distinct functional components(Mo-MXene,MoS_(2),metal sulfides),we can engineer a multiple heterogeneous interface with superior absorption capabilities,broad effective absorption bandwidths,and ultrathin matching thickness.The successful establishment of semiconductor-semiconductor-metal heterostructures gives rise to a built-in electric field that intensifies electron transfer,as confirmed by density functional theory,which collaborates with multiple dielectric polarization mechanisms to substantially amplify EMW absorption.We detailed a successful synthesis of a series of Mo-MXene/Mo-metal sulfides featuring both semiconductor-semiconductor and semiconductor-metal interfaces.The achievements were most pronounced in Mo-MXene/Mo-Sn sulfide,which achieved remarkable reflection loss values of-70.6 dB at a matching thickness of only 1.885 mm.Radar cross-section calculations indicate that these MXene/Mo-metal sulfides have tremendous potential in practical military stealth technology.This work marks a departure from conventional component design limitations and presents a novel pathway for the creation of advanced MXene-based composites with potent EMW absorption capabilities.

Modulating charge separation and transfer for high-performance photoelectrodes via built-in electric field

Constructing a built-in electric field has emerged as a key strategy for enhancing charge separation and transfer,thereby improving photoelectrochemical performance.Recently,considerable efforts have been devoted to this endeavor.This review systematically summarizes the impact of built-in electric fields on enhancing charge separation and transfer mechanisms,focusing on the modulation of built-in electric fields in terms of depth and orderliness.First,mechanisms and tuning strategies for built-in electric fields are explored.Then,the state-of-the-art works regarding built-in electric fields for modulating charge separation and transfer are summarized and categorized according to surface and interface depth.Finally,current strategies for constructing bulk built-in electric fields in photoelectrodes are explored,and insights into future developments for enhancing charge separation and transfer in high-performance photoelectrochemical applications are provided.

VSe_(2)/V_(2)C heterocatalyst with built-in electric field for efficient lithium-sulfur batteries:Remedies polysulfide shuttle and conversion kinetics

Lithium sulfur(Li-S)battery is a kind of burgeoning energy storage system with high energy density.However,the electrolyte-soluble intermediate lithium polysulfides(Li PSs)undergo notorious shuttle effect,which seriously hinders the commercialization of Li-S batteries.Herein,a unique VSe_(2)/V_(2)C heterostructure with local built-in electric field was rationally engineered from V_(2)C parent via a facile thermal selenization process.It exquisitely synergizes the strong affinity of V_(2)C with the effective electrocatalytic activity of VSe_(2).More importantly,the local built-in electric field at the heterointerface can sufficiently promote the electron/ion transport ability and eventually boost the conversion kinetics of sulfur species.The Li-S battery equipped with VSe_(2)/V_(2)C-CNTs-PP separator achieved an outstanding initial specific capacity of 1439.1 m A h g^(-1)with a high capacity retention of 73%after 100 cycles at0.1 C.More impressively,a wonderful capacity of 571.6 mA h g^(-1)was effectively maintained after 600cycles at 2 C with a capacity decay rate of 0.07%.Even under a sulfur loading of 4.8 mg cm^(-2),areal capacity still can be up to 5.6 m A h cm^(-2).In-situ Raman tests explicitly illustrate the effectiveness of VSe_(2)/V_(2)C-CNTs modifier in restricting Li PSs shuttle.Combined with density functional theory calculations,the underlying mechanism of VSe_(2)/V_(2)C heterostructure for remedying Li PSs shuttling and conversion kinetics was deciphered.The strategy of constructing VSe_(2)/V_(2)C heterocatalyst in this work proposes a universal protocol to design metal selenide-based separator modifier for Li-S battery.Besides,it opens an efficient avenue for the separator engineering of Li-S batteries.

Bimetallic selenide heterostructure with directional built-in electricfield confined in N-doped carbon nanofibers for superior sodium storage with ultralong lifespan

Constructing heterostructure is considered as an effective strategy to address the sluggish electronic and ionic kinetics of anode materials for sodium ion batteries(SIBs).However,realizing the orientated growth and uniform distribution of the heterostructure is still a great challenge.Herein,the regulated novel CoSe_(2)/NiSe_(2)heterostructure confined in N-doped carbon nanofibers(CoSe_(2)/NiSe_(2)@N-C)are prepared by using Co/Ni-ZIF template,in which,the CoSe_(2)/NiSe_(2)heterostructures realize uniform distribution on a micro level.Benefiting from the unique heterostructure and N-doped carbon nanofibers,the CoSe_(2)/NiSe_(2)@N-C deliveries superior rate capability and durable cycle lifespan with a reversible capacity of 400.5 mA h g^(-1)after 5000 cycles at 2 A g^(-1).The Na-ion full battery with CoSe_(2)/NiSe_(2)@N-C anode and layered oxide cathode displays a remarkable energy density of 563 W h kg^(-1)with 241.1 W kg^(-1)at 0.1 A g^(-1).The theoretical calculations disclose that the periodic and directional built-in electric-field along with the heterointerfaces of CoSe_(2)/NiSe_(2)@N-C can accelerate electrochemical reaction kinetics.The in(ex)situ experimental measurements reveal the reversible conversion reaction and stable structure of CoSe_(2)/NiSe_(2)@N-C during Na+insertion/extraction.The study highlights the potential ability of precisely controlled heterostructure to stimulate the electrochemical performances of advanced anode for SIBs.

Therapeutic potential of urine-derived stem cells in renal regeneration following acute kidney injury:A comparative analysis with mesenchymal stem cells

BACKGROUND Acute kidney injury(AKI)is a common clinical syndrome with high morbidity and mortality rates.The use of pluripotent stem cells holds great promise for the treatment of AKI.Urine-derived stem cells(USCs)are a novel and versatile cell source in cell-based therapy and regenerative medicine that provide advantages of a noninvasive,simple,and low-cost approach and are induced with high multidifferentiation potential.Whether these cells could serve as a potential stem cell source for the treatment of AKI has not been determined.METHODS Stem cell markers with multidifferentiation potential were isolated from human amniotic fluid.AKI severe combined immune deficiency(SCID)mice models were induced by means of an intramuscular injection with glycerol.USCs isolated from human-voided urine were administered via tail veins.The functional changes in the kidney were assessed by the levels of blood urea nitrogen and serum creatinine.The histologic changes were evaluated by hematoxylin and eosin staining and transferase dUTP nick-end labeling staining.Meanwhile,we compared the regenerative potential of USCs with bone marrow-derived mesenchymal stem cells(MSCs).RESULTS Treatment with USCs significantly alleviated histological destruction and functional decline.The renal function was rapidly restored after intravenous injection of 5×105 human USCs into SCID mice with glycerol-induced AKI compared with injection of saline.Results from secretion assays conducted in vitro demonstrated that both stem cell varieties released a wide array of cytokines and growth factors.This suggests that a mixture of various mediators closely interacts with their biochemical functions.Two types of stem cells showed enhanced tubular cell prolif-eration and decreased tubular cell apoptosis,although USC treatment was not more effective than MSC treatment.We found that USC therapy significantly improved renal function and histological damage,inhibited inflammation and apoptosis processes in the kidney,and promoted tubular epithelial proliferation.CONCLUSION Our study demonstrated the potential of USCs for the treatment of AKI,representing a new clinical therapeutic strategy.

Interfacial built-in electric field and crosslinking pathways enabling WS_(2)/Ti_(3)C_(2)T_(x) heterojunction with robust sodium storage at low temperature

Developing efficient energy storage for sodium-ion batteries(SIBs)by creating high-performance heterojunctions and understanding their interfacial interaction at the atomic/molecular level holds promise but is also challenging.Besides,sluggish reaction kinetics at low temperatures restrict the operation of SIBs in cold climates.Herein,cross-linking nanoarchitectonics of WS_(2)/Ti_(3)C_(2)T_(x) heterojunction,featuring built-in electric field(BIEF),have been developed,employing as a model to reveal the positive effect of heterojunction design and BIEF for modifying the reaction kinetics and electrochemical activity.Particularly,the theoretical analysis manifests the discrepancy in work functions leads to the electronic flow from the electron-rich Ti_(3)C_(2)T_(x) to layered WS_(2),spontaneously forming the BIEF and“ion reservoir”at the heterogeneous interface.Besides,the generation of cross-linking pathways further promotes the transportation of electrons/ions,which guarantees rapid diffusion kinetics and excellent structure coupling.Consequently,superior sodium storage performance is obtained for the WS_(2)/Ti_(3)C_(2)T_(x) heterojunction,with only 0.2%decay per cycle at 5.0 A g^(-1)(25℃)up to 1000 cycles and a high capacity of 293.5 mA h g^(-1)(0.1A g^(-1)after 100 cycles)even at-20℃.Importantly,the spontaneously formed BIEF,accompanied by“ion reservoir”,in heterojunction provides deep understandings of the correlation between structure fabricated and performance obtained.