Plant cell wall(CW)-like soft materials,referred to as artificial CWs,are composites of assembled polymers containing micro-/nanoparticles or fibers/fibrils that are designed to mimic the composition,structure,and mec...Plant cell wall(CW)-like soft materials,referred to as artificial CWs,are composites of assembled polymers containing micro-/nanoparticles or fibers/fibrils that are designed to mimic the composition,structure,and mechanics of plant CWs.CW-like materials have recently emerged to test hypotheses pertaining to the intricate structure–property relationships of native plant CWs or to fabricate functional materials.Here,research on plant CWs and CW-like materials is reviewed by distilling key studies on biomimetic composites primarily composed of plant polysaccharides,including cellulose,pectin,and hemicellulose,as well as organic polymers like lignin.Micro-and nanofabrication of plant CW-like composites,characterization techniques,and in silico studies are reviewed,with a brief overview of current and potential applications.Micro-/nanofabrication approaches include bacterial growth and impregnation,layer-by-layer assembly,film casting,3-dimensional templating microcapsules,and particle coating.Various characterization techniques are necessary for the comprehensive mechanical,chemical,morphological,and structural analyses of plant CWs and CW-like materials.CW-like materials demonstrate versatility in real-life applications,including biomass conversion,pulp and paper,food science,construction,catalysis,and reaction engineering.This review seeks to facilitate the rational design and thorough characterization of plant CW-mimetic materials,with the goal of advancing the development of innovative soft materials and elucidating the complex structure–property relationships inherent in native CWs.展开更多
Emerging therapies rely on the efficient and specific delivery of targeted agents into the cytosol,such as DNA,siRNA and proteins.Nanoparticles showed great potentials in safe delivery and transportation of the target...Emerging therapies rely on the efficient and specific delivery of targeted agents into the cytosol,such as DNA,siRNA and proteins.Nanoparticles showed great potentials in safe delivery and transportation of the targeted cargoes;however,the entrapment in endosomes and degradation by specific enzymes in the lysosome hindered the bioavailability,cytosolic delivery and subsequent therapeutic efficacy.In this case,the development of methods for efficient and specific delivery of targeted therapeutic agents focuses on overcoming the major challenge of endo/lysosomal escape,which relies on the development of safe and efficient nanodelivery systems.A deeper mechanistic understanding in the endo/lysosomal escape will guide the development of more efficient nano-delivery systems.In this review,we summarize various mechanisms by which nanoparticles escape from the endo/lysosome,and showcase the recent progress in dissecting the endo/lysosomal approaches based on nano-delivery systems.Emphasis will lie on the properties of nanoparticles that govern the endo/lysosomal escape pathway as well as the latest promising applications in vaccine delivery and genetic engineering field.展开更多
This paper expounds professional characteristics of biomedical engineering in our school, and analyses some problems lying in it, emphatically discusses advantages and the problems combining biomedical engineering wit...This paper expounds professional characteristics of biomedical engineering in our school, and analyses some problems lying in it, emphatically discusses advantages and the problems combining biomedical engineering with the medical courses in order to offer targeted solutions. It summarizes the results and problems so as to provide reference value to a new major.展开更多
Although previous studies have demonstrated that transcranial focused ultrasound stimulation protects the ischemic brain,clear criteria for the stimulation time window and intensity are lacking.Electrical impedance to...Although previous studies have demonstrated that transcranial focused ultrasound stimulation protects the ischemic brain,clear criteria for the stimulation time window and intensity are lacking.Electrical impedance tomography enables real-time monitoring of changes in cerebral blood perfusion within the ischemic brain,but investigating the feasibility of using this method to assess post-stroke rehabilitation in vivo remains critical.In this study,ischemic stroke was induced in rats through middle cerebral artery occlusion surgery.Transcranial focused ultrasound stimulation was used to treat the rat model of ischemia,and electrical impedance tomography was used to measure impedance during both the acute stage of ischemia and the rehabilitation stage following the stimulation.Electrical impedance tomography results indicated that cerebral impedance increased after the onset of ischemia and decreased following transcranial focused ultrasound stimulation.Furthermore,the stimulation promoted motor function recovery,reduced cerebral infarction volume in the rat model of ischemic stroke,and induced the expression of brain-derived neurotrophic factor in the ischemic brain.Our results also revealed a significant correlation between the impedance of the ischemic brain post-intervention and improvements in behavioral scores and infarct volume.This study shows that daily administration of transcranial focused ultrasound stimulation for 20 minutes to the ischemic hemisphere 24 hours after cerebral ischemia enhanced motor recovery in a rat model of ischemia.Additionally,our findings indicate that electrical impedance tomography can serve as a valuable tool for quantitatively evaluating rehabilitation after ischemic stroke in vivo.These findings suggest the feasibility of using impedance data collected via electrical impedance tomography to clinically assess the effects of rehabilitatory interventions for patients with ischemic stroke.展开更多
Gelatin/Alginate hydrogels were engineered for bioplotting in tissue engineering.One major drawback of hydrogel scaffolds is the lack of adequate mechanical properties.In this study,using a bioplotter,we constructed t...Gelatin/Alginate hydrogels were engineered for bioplotting in tissue engineering.One major drawback of hydrogel scaffolds is the lack of adequate mechanical properties.In this study,using a bioplotter,we constructed the scaffolds with different pore architectures by deposition of gelatin/alginate hydrogels layerby-layer.The scaffolds with different crosslinking degree were obtained by post-crosslinking methods.Their physicochemical properties,as well as cell viability,were assessed.Different crosslinking methods had little influence on scaffold architecture,porosity,pore size and distribution.By contrast,the water absorption ability,degradation rate and mechanical properties of the scaffolds were dramatically affected by treatment with various concentrations of crosslinking agent(glutaraldehyde).The crosslinking process using glutaraldehyde markedly improved the stability and mechanical strength of the hydrogel scaf-folds.Besides the post-processing methods,the pore architecture can also evidently affect the mechanical properties of the scaffolds.The crosslinked gelatin/alginate scaffolds showed a good potential to encap-sulate cells or drugs.展开更多
Bone tissue engineering is an exciting approach to directly repair bone defects or engineer bone tissue for transplantation.Biomaterials play a pivotal role in providing a template and extracellular environment to sup...Bone tissue engineering is an exciting approach to directly repair bone defects or engineer bone tissue for transplantation.Biomaterials play a pivotal role in providing a template and extracellular environment to support regenerative cells and promote tissue regeneration. A variety of signaling cues have been identified to regulate cellular activity, tissue development, and the healing process. Numerous studies and trials have shown the promise of tissue engineering, but successful translations of bone tissue engineering research into clinical applications have been limited, due in part to a lack of optimal delivery systems for these signals. Biomedical engineers are therefore highly motivated to develop biomimetic drug delivery systems, which benefit from mimicking signaling molecule release or presentation by the native extracellular matrix during development or the natural healing process. Engineered biomimetic drug delivery systems aim to provide control over the location, timing, and release kinetics of the signal molecules according to the drug's physiochemical properties and specific biological mechanisms. This article reviews biomimetic strategies in signaling delivery for bone tissue engineering, with a focus on delivery systems rather than specific molecules. Both fundamental considerations and specific design strategies are discussed with examples of recent research progress, demonstrating the significance and potential of biomimetic delivery systems for bone tissue engineering.展开更多
Stents made of nearly equiatomic NiTi alloy are used to treat malignant obstruction caused by cancer,but prevention of re-obstruction after surgery is still a challenge because the bare stents possess poor anticancer ...Stents made of nearly equiatomic NiTi alloy are used to treat malignant obstruction caused by cancer,but prevention of re-obstruction after surgery is still a challenge because the bare stents possess poor anticancer and antibacterial properties to inhibit cancer/bacteria invasion.The present work aims at endowing the NiTi alloy with anticancer and antibacterial abilities by surface modification.Ni–Ti–O nanoporous layers with different thicknesses were prepared on NiTi by anodization,and biological experiments were conducted to evaluate the effects on gram-positive Staphylococcus aureus,human lung epithelial cancer cells(A549),as well as human endothelial cells(EA.hy926).The nanoporous layer with a thickness of 10.1 lm inhibits growth of cancer cells and kill bacteria but shows little adverse effects on normal cells.Such selectivity is related to the larger amount of Ni ions leached from the sample in the acidic microenvironment of cancer cells in comparison with normal cells.The Ni–Ti–O nanoporous layers are promising as coatings on NiTi stents to prevent re-obstruction after surgery.展开更多
Inspired by the skin structure,an asymmetric wettability tri-layer nanofiber membrane(TNM)consisting of hydrophilic inner layer loaded with lidocaine hydrochloride(LID),hydrophobic middle layer with ciprofloxacin(CIP)...Inspired by the skin structure,an asymmetric wettability tri-layer nanofiber membrane(TNM)consisting of hydrophilic inner layer loaded with lidocaine hydrochloride(LID),hydrophobic middle layer with ciprofloxacin(CIP)and hydrophobic outer layer has been created.The hydrophobic outer layer endows the TNM with waterproof function and anti-adhesion from contaminants.The hydrophobic middle layer with CIP preserves long-term inhibition of bacteria growth and the hydrophilic inner layer with LID possesses optimal waterabsorbing capacity and air permeability.The TNM dramatically elevates the water contact angles from 10°(inner layer)to 120(outer layer),indicating an asymmetric wettability,which could directionally transport wound exudate within the materials and meanwhile maintain a comfortable and moist environment to promote wound healing.Furthermore,the sequential release of LID and CIP could relieve pain rapidly and achieve antibacterial effect in the long run,respectively.In addition,the TNM shows superior biocompatibility towards L929 cells.The in vivo results show the TNM could prevent infection,accelerate epithelial regeneration and significantly accelerate wound healing.This study indicates the developed TNM with asymmetrical wettability and synergetic drug release shows great potential as a wound dressing in clinical application.展开更多
Treatment for central nervous system(CNS)disorders is known to be limited by the low regenerative potential of neurons,and thus neurodegenerative insults became known as nearly irreversible ailments.Functional recover...Treatment for central nervous system(CNS)disorders is known to be limited by the low regenerative potential of neurons,and thus neurodegenerative insults became known as nearly irreversible ailments.Functional recovery for acquired CNS disorders,such as spinal cord injury(SCI),traumatic brain injury,ischemic stroke,Alzheimer’s disease,Parkinson’s disease,multiple sclerosis(MS),and for congenital CNS abnormalities,such as spina bifida,is not spontaneous and effective treatments are limited to non-existent.Research in the past decades has proven the regenerative potential of stem cells,especially that of mesenchymal stromal/stem cells(MSCs)from various origins,such as bone marrow,placenta,and adipose tissue.展开更多
The strong texture of Mg alloys can lead to strong tension–compression yield asymmetry and corrosion anisotropy,and this will consequently affect the effectiveness of hard tissue implants.A biomedical Mg–6Zn–0.5Zr ...The strong texture of Mg alloys can lead to strong tension–compression yield asymmetry and corrosion anisotropy,and this will consequently affect the effectiveness of hard tissue implants.A biomedical Mg–6Zn–0.5Zr alloy containing a large number of{1012}primary twins and{1012}–{1012}secondary twins is successfully prepared by cross compression.The dual twin structure not only removes the tension–compression yield asymmetry completely,but effectively reduces the corrosion anisotropy without compromise of corrosion resistance.The difference between the largest corrosion rate and smallest one is~1.2 times compared to~1.6 times of the original materials.It is found that the reduced corrosion anisotropy is related to re-distribution of crystallographic orientations by twins.展开更多
Tissue engineering is nowadays an emerging approach that aims to replace or regenerate diseased or damaged organs with engineered constructs. Considering the key role of growth factors (GFs) in the tissue regeneration...Tissue engineering is nowadays an emerging approach that aims to replace or regenerate diseased or damaged organs with engineered constructs. Considering the key role of growth factors (GFs) in the tissue regeneration process, these biomolecules are considered an important part of the tissue engineering process, so the presence of growth factors in engineered scaffolds can accelerate tissue regeneration by influencing the behavior of cells. Platelet-rich plasma (PRP), as an autologous source of a variety of growth factors, is considered a therapeutic agent for the treatment of degenerative diseases. Regarding its ability to promote the healing process and tissue regeneration, PRP therapy has attracted great attention in bone and cartilage tissue engineering. Incorporating PRP and its derivatives into engineered scaffolds not only bioactivates the scaffold, but the scaffold matrix also acts as a sustained and localized growth factor release system. In addition, the presence of a scaffold can promote the bioactivity of GFs by providing an environment that facilitates their interaction, leading to enhanced effects compared to their free form. This review presents a brief overview of PRP's role in bone and cartilage tissue regeneration with the main focus on scaffold-mediated PRP delivery. In addition, the classification of platelet-rich products, current extraction techniques, terminology, and scaffold bioactivation methods are presented to provide a better understanding of the basics and the key aspects that may affect the effectiveness of therapy in bone and cartilage tissue engineering.展开更多
The most common complication of orthopedic surgery is implant failure, which can result in catastrophic injury and a significant financial burden for patients. Implant failure can be caused by a variety of factors, th...The most common complication of orthopedic surgery is implant failure, which can result in catastrophic injury and a significant financial burden for patients. Implant failure can be caused by a variety of factors, the most common of which are peri–implant infection(or implantrelated infection), excessive inflammatory response which caused pain and aseptic loosening. Orthopedic surgeons now have a variety of options for treating these issues, including revision surgery, which has demonstrated to be effective. If excessive inflammatory reaction caused by the corrosion and peri–implant infection can be avoided, it will be of enormous social benefits. This review will provide a summary of corrosion and the inflammation reactions due to the corrosion and antimicrobial properties of Mg alloy-based implants covering both in vitro and in vivo studies. The strategies on hindering/overcoming the excessive inflammatory response and enhancing the antimicrobial activity are discussed in this review.展开更多
Efficient electrocatalysts are vital to large-current hydrogen production in commercial water splitting for green energy generation.Herein,a novel heterophase engineering strategy is described to produce polymorphic C...Efficient electrocatalysts are vital to large-current hydrogen production in commercial water splitting for green energy generation.Herein,a novel heterophase engineering strategy is described to produce polymorphic CoSe_(2)electrocatalysts.The composition of the electrocatalysts consisting of both cubic CoSe_(2)(c-CoSe_(2))and orthorhombic CoSe_(2)(o-CoSe_(2))phases can be controlled precisely.Our results demonstrate that junction-induced spin-state modulation of Co atoms enhances the adsorption of intermediates and accelerates charge transfer resulting in superior large-current hydrogen evolution reaction(HER)properties.Specifically,the CoSe_(2)based heterophase catalyst with the optimal c-CoSe_(2)content requires an overpotential of merely 240 mV to achieve 1,000 mA·cm^(-2)as well as a Tafel slope of 50.4 mV·dec^(-1).Furthermore,the electrocatalyst can maintain a large current density of 1,500 mA·cm^(-2)for over 320 h without decay.The results reveal the advantages and potential of heterophase junction engineering pertaining to design and fabrication of low-cost transition metal catalysts for large-current water splitting.展开更多
If the 20th century was the age of mapping and controlling the external world,the 21st century is the biomedical age of mapping and controlling the biological internal world.The biomedical age is bringing new technolo...If the 20th century was the age of mapping and controlling the external world,the 21st century is the biomedical age of mapping and controlling the biological internal world.The biomedical age is bringing new technological breakthroughs for sensing and controlling human biomolecules,cells,tissues,and organs,which underpin new frontiers in the biomedical discovery,data,biomanufacturing,and translational sciences.This article reviews what we believe will be the next wave of biomedical engineering(BME)education in support of the biomedical age,what we have termed BME 2.0.BME 2.0 was announced on October 122017 at BMES 49(https://www.bme.jhu.edu/news-events/news/miller-opens-2017-bmes-annual-meeting-with-vision-for-new-bme-era/).We present several principles upon which we believe the BME 2.0 curriculum should be constructed,and from these principles,we describe what view as the foundations that form the next generations of curricula in support of the BME enterprise.The core principles of BME 2.0 education are(a)educate students bilingually,from day 1,in the languages of modern molecular biology and the analytical modeling of complex biological systems;(b)prepare every student to be a biomedical data scientist;(c)build a unique BME community for discovery and innovation via a vertically integrated and convergent learning environment spanning the university and hospital systems;(d)champion an educational culture of inclusive excellence;and(e)codify in the curriculum ongoing discoveries at the frontiers of the discipline,thus ensuring BME 2.0 as a launchpad for training the future leaders of the biotechnology marketplaces.We envision that the BME 2.0 education is the path for providing every student with the training to lead in this new era of engineering the future of medicine in the 21st century.展开更多
The therapeutic replacement of diseased tubular tissue is hindered by the availability and suitability of current donor, autologous and synthetically derived protheses. Artificially created, tissue engineered, constru...The therapeutic replacement of diseased tubular tissue is hindered by the availability and suitability of current donor, autologous and synthetically derived protheses. Artificially created, tissue engineered, constructs have the potential to alleviate these concerns with reduced autoimmune response, high anatomical accuracy, long-term patency and growth potential. The advent of 3D bioprinting technology has further supplemented the technological toolbox, opening up new biofabrication research opportunities and expanding the therapeutic potential of the field. In this review, we highlight the challenges facing those seeking to create artificial tubular tissue with its associated complex macro- and microscopic architecture. Current biofabrication approaches, including 3D printing techniques, are reviewed and future directions suggested.展开更多
Peripheral nerve injury is a common neurological condition that often leads to severe functional limitations and disabilities.Research on the pathogenesis of peripheral nerve injury has focused on pathological changes...Peripheral nerve injury is a common neurological condition that often leads to severe functional limitations and disabilities.Research on the pathogenesis of peripheral nerve injury has focused on pathological changes at individual injury sites,neglecting multilevel pathological analysis of the overall nervous system and target organs.This has led to restrictions on current therapeutic approaches.In this paper,we first summarize the potential mechanisms of peripheral nerve injury from a holistic perspective,covering the central nervous system,peripheral nervous system,and target organs.After peripheral nerve injury,the cortical plasticity of the brain is altered due to damage to and regeneration of peripheral nerves;changes such as neuronal apoptosis and axonal demyelination occur in the spinal cord.The nerve will undergo axonal regeneration,activation of Schwann cells,inflammatory response,and vascular system regeneration at the injury site.Corresponding damage to target organs can occur,including skeletal muscle atrophy and sensory receptor disruption.We then provide a brief review of the research advances in therapeutic approaches to peripheral nerve injury.The main current treatments are conducted passively and include physical factor rehabilitation,pharmacological treatments,cell-based therapies,and physical exercise.However,most treatments only partially address the problem and cannot complete the systematic recovery of the entire central nervous system-peripheral nervous system-target organ pathway.Therefore,we should further explore multilevel treatment options that produce effective,long-lasting results,perhaps requiring a combination of passive(traditional)and active(novel)treatment methods to stimulate rehabilitation at the central-peripheral-target organ levels to achieve better functional recovery.展开更多
Tissue engineering’s main goal is to regenerate or replace tissues or organs that have been destroyed by disease,injury,or congenital disabilities.Tissue engineering now uses artificial supporting structures called s...Tissue engineering’s main goal is to regenerate or replace tissues or organs that have been destroyed by disease,injury,or congenital disabilities.Tissue engineering now uses artificial supporting structures called scaffolds to restore damaged tissues and organs.These are utilized to attach the right cells and then grow them.Rapid prototyping appears to be the most promising technology due to its high level of precision and control.Bone tissue replacement“scaffolding”is a common theme discussed in this article.The fused deposition technique was used to construct our scaffold,and a polymer called polylactic acids and soybean oil resin were used to construct our samples.The samples were then divided into two groups;the first group was left without immersion in the simulated body fluid and served as a control for comparison.The second group was immersed in the simulated body fluid.The results of the Field Emission Scanning Electron Microscope(FESEM),Energy Dispersive X-ray Spectroscopy(EDX)and X-ray diffraction(XRD)were utilized to interpret the surface attachment to ions,elements,and compounds,giving us a new perspective on scaffold architecture.In this study,an innovative method has been used to print therapeutic scaffold that combines fused deposition three-dimensional printing with ultraviolet curing to create a high-quality biodegradable polymeric scaffold.Finally,the results demonstrate that adding soybean oil resin to the PLA increased ion attachment to the surface while also attracting tricalcium phosphate formation on the surface of the scaffold,which is highly promising in bone tissue replacement.In conclusion,the soybean oil resin,which is new in the field of bone tissue engineering,shows magnificent characteristics and is a good replacement biopolymer that replaces many ceramic and polymeric materials used in this field that have poor morphological characteristics.展开更多
The brain is one of the most important organs in a biological body which can only work in a relatively stable temperature range. However, many environmental factors in biosphere would cause cerebral temperature fluctu...The brain is one of the most important organs in a biological body which can only work in a relatively stable temperature range. However, many environmental factors in biosphere would cause cerebral temperature fluctuations. To sustain and regulate the brain temperature, many mechanisms of biological brain cooling have been evolved, including Selective Brain Cooling （SBC）, cooling through surface water evaporation, respiration, behavior response and using special anatomical ap- pendages. This article is dedicated to present a summarization and systematic interpretation on brain cooling strategies devel- oped in animals by classifying and comparatively analyzing each typical biological brain cooling mechanism from the per- spective of bio-heat transfer. Meanwhile, inspirations from such cooling in nature were proposed for developing advanced bionic engineering technologies especially with two focuses on therapeutic hypothermia and computer chip cooling areas. It is expected that many innovations can be achieved along this way to find out new cooling methodologies for a wide variety of industrial applications which will be highly efficient, energy saving, flexible or even intelligent.展开更多
Engineered cardiac constructs(ECC)aid in the progression of regenerative medicine,disease modeling and targeted drug delivery to adjust and aim the release of remedial combination as well as decrease the side effects ...Engineered cardiac constructs(ECC)aid in the progression of regenerative medicine,disease modeling and targeted drug delivery to adjust and aim the release of remedial combination as well as decrease the side effects of drugs.In this research,polycaprolactone/gold nanoparticles(PCL/GNPs)three-dimensional(3D)composite scaffolds were manufactured by 3D printing using the fused deposition modeling(FDM)method and then coated with gelatin/spironolactone(GEL/SPL).Scanning electron microscopy(SEM)and Fourier transform-infrared spectroscopy(FTIR–ATR)were applied to characterize the samples.Furthermore,drug release,biodegradation,behavior of the myoblasts(H9C2)cell line,and cytotoxicity of the 3D scaffolds were evaluated.The microstructural observation of the scaffolds reported interconnected pores with 150–300µm in diameter.The 3D scaffolds were degraded significantly after 28 days of immersion in stimulated body fluid(SBF),with the maximum rate of GEL-coated 3D scaffolds.SPL release from cross-linked GEL coating demonstrated the excess of drug release over time,and according to the control release systems,the drug delivery systems(DDS)went into balance after the 14th day.In addition,cell culture study showed that with the addition of GNPs,the proliferation of(H9C2)was enhanced,and with GEL/SPL coating the cell attachment and viability were improved significantly.These findings suggested that PCL/GNPs 3D scaffolds coated with GEL/SPL can be an appropriate choice for myocardial tissue engineering.展开更多
In the article“BME 2.0:Engineering the Future of Medicine”[1],the competing interests statement was inadvertently omitted by the publisher from the published version of the article.This has now been corrected in the...In the article“BME 2.0:Engineering the Future of Medicine”[1],the competing interests statement was inadvertently omitted by the publisher from the published version of the article.This has now been corrected in the PDF and HTML(full text).展开更多
基金supported as part of The Center for LignoCellulose Structure and Formation,an Energy Frontier Research Center funded by the U.S.Department of Energy,Office of Science,Basic Energy Sciences under Award#DE-SC0001090support from the Huck Institutes of the Life Sciences at Penn State University through the Patricia and Stephen Benkovic Research Initiativesupported by the Center for Engineering Mechano Biology(CEMB),an NSF Science and Technology Center,under grant agreement CMMI:15-48571。
文摘Plant cell wall(CW)-like soft materials,referred to as artificial CWs,are composites of assembled polymers containing micro-/nanoparticles or fibers/fibrils that are designed to mimic the composition,structure,and mechanics of plant CWs.CW-like materials have recently emerged to test hypotheses pertaining to the intricate structure–property relationships of native plant CWs or to fabricate functional materials.Here,research on plant CWs and CW-like materials is reviewed by distilling key studies on biomimetic composites primarily composed of plant polysaccharides,including cellulose,pectin,and hemicellulose,as well as organic polymers like lignin.Micro-and nanofabrication of plant CW-like composites,characterization techniques,and in silico studies are reviewed,with a brief overview of current and potential applications.Micro-/nanofabrication approaches include bacterial growth and impregnation,layer-by-layer assembly,film casting,3-dimensional templating microcapsules,and particle coating.Various characterization techniques are necessary for the comprehensive mechanical,chemical,morphological,and structural analyses of plant CWs and CW-like materials.CW-like materials demonstrate versatility in real-life applications,including biomass conversion,pulp and paper,food science,construction,catalysis,and reaction engineering.This review seeks to facilitate the rational design and thorough characterization of plant CW-mimetic materials,with the goal of advancing the development of innovative soft materials and elucidating the complex structure–property relationships inherent in native CWs.
基金support from the Postdoctoral Fellowship Scheme of The Chinese University of Hong Kong,the Postdoctoral Fellowship Program of CPSF(GZC20241828)The China Postdoctoral Science Foundation(2024M763416).
文摘Emerging therapies rely on the efficient and specific delivery of targeted agents into the cytosol,such as DNA,siRNA and proteins.Nanoparticles showed great potentials in safe delivery and transportation of the targeted cargoes;however,the entrapment in endosomes and degradation by specific enzymes in the lysosome hindered the bioavailability,cytosolic delivery and subsequent therapeutic efficacy.In this case,the development of methods for efficient and specific delivery of targeted therapeutic agents focuses on overcoming the major challenge of endo/lysosomal escape,which relies on the development of safe and efficient nanodelivery systems.A deeper mechanistic understanding in the endo/lysosomal escape will guide the development of more efficient nano-delivery systems.In this review,we summarize various mechanisms by which nanoparticles escape from the endo/lysosome,and showcase the recent progress in dissecting the endo/lysosomal approaches based on nano-delivery systems.Emphasis will lie on the properties of nanoparticles that govern the endo/lysosomal escape pathway as well as the latest promising applications in vaccine delivery and genetic engineering field.
文摘This paper expounds professional characteristics of biomedical engineering in our school, and analyses some problems lying in it, emphatically discusses advantages and the problems combining biomedical engineering with the medical courses in order to offer targeted solutions. It summarizes the results and problems so as to provide reference value to a new major.
基金supported by the Fundamental Research Funds for the Central Universities,Nos.G2021KY05107,G2021KY05101the National Natural Science Foundation of China,Nos.32071316,32211530049+1 种基金the Natural Science Foundation of Shaanxi Province,No.2022-JM482the Education and Teaching Reform Funds for the Central Universities,No.23GZ230102(all to LL and HH).
文摘Although previous studies have demonstrated that transcranial focused ultrasound stimulation protects the ischemic brain,clear criteria for the stimulation time window and intensity are lacking.Electrical impedance tomography enables real-time monitoring of changes in cerebral blood perfusion within the ischemic brain,but investigating the feasibility of using this method to assess post-stroke rehabilitation in vivo remains critical.In this study,ischemic stroke was induced in rats through middle cerebral artery occlusion surgery.Transcranial focused ultrasound stimulation was used to treat the rat model of ischemia,and electrical impedance tomography was used to measure impedance during both the acute stage of ischemia and the rehabilitation stage following the stimulation.Electrical impedance tomography results indicated that cerebral impedance increased after the onset of ischemia and decreased following transcranial focused ultrasound stimulation.Furthermore,the stimulation promoted motor function recovery,reduced cerebral infarction volume in the rat model of ischemic stroke,and induced the expression of brain-derived neurotrophic factor in the ischemic brain.Our results also revealed a significant correlation between the impedance of the ischemic brain post-intervention and improvements in behavioral scores and infarct volume.This study shows that daily administration of transcranial focused ultrasound stimulation for 20 minutes to the ischemic hemisphere 24 hours after cerebral ischemia enhanced motor recovery in a rat model of ischemia.Additionally,our findings indicate that electrical impedance tomography can serve as a valuable tool for quantitatively evaluating rehabilitation after ischemic stroke in vivo.These findings suggest the feasibility of using impedance data collected via electrical impedance tomography to clinically assess the effects of rehabilitatory interventions for patients with ischemic stroke.
基金supported by the National Basic Research Program of China(“973 Program”,No.2012CB619100)the National Natural Science Foundation of China(Grant No.51372085)+1 种基金the Guangdong–Hongkong Common Technology Bidding Project(No.2013B010136003)the Postdoctoral Science Foundation of China(No.2013M542172)
文摘Gelatin/Alginate hydrogels were engineered for bioplotting in tissue engineering.One major drawback of hydrogel scaffolds is the lack of adequate mechanical properties.In this study,using a bioplotter,we constructed the scaffolds with different pore architectures by deposition of gelatin/alginate hydrogels layerby-layer.The scaffolds with different crosslinking degree were obtained by post-crosslinking methods.Their physicochemical properties,as well as cell viability,were assessed.Different crosslinking methods had little influence on scaffold architecture,porosity,pore size and distribution.By contrast,the water absorption ability,degradation rate and mechanical properties of the scaffolds were dramatically affected by treatment with various concentrations of crosslinking agent(glutaraldehyde).The crosslinking process using glutaraldehyde markedly improved the stability and mechanical strength of the hydrogel scaf-folds.Besides the post-processing methods,the pore architecture can also evidently affect the mechanical properties of the scaffolds.The crosslinked gelatin/alginate scaffolds showed a good potential to encap-sulate cells or drugs.
基金supported by the US DOD(W81XWH-12-2-0008)the National Institutes of Health(DE022327,HL136231,TR001711)the National Natural Science Foundation of China(Grant No.31470915)
文摘Bone tissue engineering is an exciting approach to directly repair bone defects or engineer bone tissue for transplantation.Biomaterials play a pivotal role in providing a template and extracellular environment to support regenerative cells and promote tissue regeneration. A variety of signaling cues have been identified to regulate cellular activity, tissue development, and the healing process. Numerous studies and trials have shown the promise of tissue engineering, but successful translations of bone tissue engineering research into clinical applications have been limited, due in part to a lack of optimal delivery systems for these signals. Biomedical engineers are therefore highly motivated to develop biomimetic drug delivery systems, which benefit from mimicking signaling molecule release or presentation by the native extracellular matrix during development or the natural healing process. Engineered biomimetic drug delivery systems aim to provide control over the location, timing, and release kinetics of the signal molecules according to the drug's physiochemical properties and specific biological mechanisms. This article reviews biomimetic strategies in signaling delivery for bone tissue engineering, with a focus on delivery systems rather than specific molecules. Both fundamental considerations and specific design strategies are discussed with examples of recent research progress, demonstrating the significance and potential of biomimetic delivery systems for bone tissue engineering.
基金This study was financially supported by the Fund for Shanxi"1331 Project"Key Innovative Research Team(No.PY201809)the Natural Science Foundation of Shanxi Province(No.201801D121093)Hong Kong Research Grants Council General Research Funds(No.CityU 11205617).
文摘Stents made of nearly equiatomic NiTi alloy are used to treat malignant obstruction caused by cancer,but prevention of re-obstruction after surgery is still a challenge because the bare stents possess poor anticancer and antibacterial properties to inhibit cancer/bacteria invasion.The present work aims at endowing the NiTi alloy with anticancer and antibacterial abilities by surface modification.Ni–Ti–O nanoporous layers with different thicknesses were prepared on NiTi by anodization,and biological experiments were conducted to evaluate the effects on gram-positive Staphylococcus aureus,human lung epithelial cancer cells(A549),as well as human endothelial cells(EA.hy926).The nanoporous layer with a thickness of 10.1 lm inhibits growth of cancer cells and kill bacteria but shows little adverse effects on normal cells.Such selectivity is related to the larger amount of Ni ions leached from the sample in the acidic microenvironment of cancer cells in comparison with normal cells.The Ni–Ti–O nanoporous layers are promising as coatings on NiTi stents to prevent re-obstruction after surgery.
文摘Inspired by the skin structure,an asymmetric wettability tri-layer nanofiber membrane(TNM)consisting of hydrophilic inner layer loaded with lidocaine hydrochloride(LID),hydrophobic middle layer with ciprofloxacin(CIP)and hydrophobic outer layer has been created.The hydrophobic outer layer endows the TNM with waterproof function and anti-adhesion from contaminants.The hydrophobic middle layer with CIP preserves long-term inhibition of bacteria growth and the hydrophilic inner layer with LID possesses optimal waterabsorbing capacity and air permeability.The TNM dramatically elevates the water contact angles from 10°(inner layer)to 120(outer layer),indicating an asymmetric wettability,which could directionally transport wound exudate within the materials and meanwhile maintain a comfortable and moist environment to promote wound healing.Furthermore,the sequential release of LID and CIP could relieve pain rapidly and achieve antibacterial effect in the long run,respectively.In addition,the TNM shows superior biocompatibility towards L929 cells.The in vivo results show the TNM could prevent infection,accelerate epithelial regeneration and significantly accelerate wound healing.This study indicates the developed TNM with asymmetrical wettability and synergetic drug release shows great potential as a wound dressing in clinical application.
基金supported by Shriner’s Hospital for Children(85108-NCA-19)the NIH(5R01NS100761)。
文摘Treatment for central nervous system(CNS)disorders is known to be limited by the low regenerative potential of neurons,and thus neurodegenerative insults became known as nearly irreversible ailments.Functional recovery for acquired CNS disorders,such as spinal cord injury(SCI),traumatic brain injury,ischemic stroke,Alzheimer’s disease,Parkinson’s disease,multiple sclerosis(MS),and for congenital CNS abnormalities,such as spina bifida,is not spontaneous and effective treatments are limited to non-existent.Research in the past decades has proven the regenerative potential of stem cells,especially that of mesenchymal stromal/stem cells(MSCs)from various origins,such as bone marrow,placenta,and adipose tissue.
基金supported by the National Natural Science Foundation of China(Nos.52101132,51871032 and 51901202)the Natural Science Foundation of Jiangsu Province(No.BK20202010)+1 种基金the Basic and Applied Basic Research Project of Guangzhou(202201011250)the City University of Hong Kong Strategic Research Grant(No.7005264).
文摘The strong texture of Mg alloys can lead to strong tension–compression yield asymmetry and corrosion anisotropy,and this will consequently affect the effectiveness of hard tissue implants.A biomedical Mg–6Zn–0.5Zr alloy containing a large number of{1012}primary twins and{1012}–{1012}secondary twins is successfully prepared by cross compression.The dual twin structure not only removes the tension–compression yield asymmetry completely,but effectively reduces the corrosion anisotropy without compromise of corrosion resistance.The difference between the largest corrosion rate and smallest one is~1.2 times compared to~1.6 times of the original materials.It is found that the reduced corrosion anisotropy is related to re-distribution of crystallographic orientations by twins.
基金support from Iran’s National Elites Foundation(INEF).
文摘Tissue engineering is nowadays an emerging approach that aims to replace or regenerate diseased or damaged organs with engineered constructs. Considering the key role of growth factors (GFs) in the tissue regeneration process, these biomolecules are considered an important part of the tissue engineering process, so the presence of growth factors in engineered scaffolds can accelerate tissue regeneration by influencing the behavior of cells. Platelet-rich plasma (PRP), as an autologous source of a variety of growth factors, is considered a therapeutic agent for the treatment of degenerative diseases. Regarding its ability to promote the healing process and tissue regeneration, PRP therapy has attracted great attention in bone and cartilage tissue engineering. Incorporating PRP and its derivatives into engineered scaffolds not only bioactivates the scaffold, but the scaffold matrix also acts as a sustained and localized growth factor release system. In addition, the presence of a scaffold can promote the bioactivity of GFs by providing an environment that facilitates their interaction, leading to enhanced effects compared to their free form. This review presents a brief overview of PRP's role in bone and cartilage tissue regeneration with the main focus on scaffold-mediated PRP delivery. In addition, the classification of platelet-rich products, current extraction techniques, terminology, and scaffold bioactivation methods are presented to provide a better understanding of the basics and the key aspects that may affect the effectiveness of therapy in bone and cartilage tissue engineering.
文摘The most common complication of orthopedic surgery is implant failure, which can result in catastrophic injury and a significant financial burden for patients. Implant failure can be caused by a variety of factors, the most common of which are peri–implant infection(or implantrelated infection), excessive inflammatory response which caused pain and aseptic loosening. Orthopedic surgeons now have a variety of options for treating these issues, including revision surgery, which has demonstrated to be effective. If excessive inflammatory reaction caused by the corrosion and peri–implant infection can be avoided, it will be of enormous social benefits. This review will provide a summary of corrosion and the inflammation reactions due to the corrosion and antimicrobial properties of Mg alloy-based implants covering both in vitro and in vivo studies. The strategies on hindering/overcoming the excessive inflammatory response and enhancing the antimicrobial activity are discussed in this review.
基金financially supported by the National Natural Science Foundation of China(Nos.52002294 and 52202111)the Key Research and Development Program of Hubei Province(No.2021BAA208)+3 种基金the Knowledge Innovation Program of Wuhan-Shuguang Project(No.2022010801020364)City University of Hong Kong Donation Research Grant(No.DON-RMG 9229021)City University of Hong Kong Donation Grant(No.9220061)City University of Hong Kong Strategic Research Grant(SRG)(No.7005505)。
文摘Efficient electrocatalysts are vital to large-current hydrogen production in commercial water splitting for green energy generation.Herein,a novel heterophase engineering strategy is described to produce polymorphic CoSe_(2)electrocatalysts.The composition of the electrocatalysts consisting of both cubic CoSe_(2)(c-CoSe_(2))and orthorhombic CoSe_(2)(o-CoSe_(2))phases can be controlled precisely.Our results demonstrate that junction-induced spin-state modulation of Co atoms enhances the adsorption of intermediates and accelerates charge transfer resulting in superior large-current hydrogen evolution reaction(HER)properties.Specifically,the CoSe_(2)based heterophase catalyst with the optimal c-CoSe_(2)content requires an overpotential of merely 240 mV to achieve 1,000 mA·cm^(-2)as well as a Tafel slope of 50.4 mV·dec^(-1).Furthermore,the electrocatalyst can maintain a large current density of 1,500 mA·cm^(-2)for over 320 h without decay.The results reveal the advantages and potential of heterophase junction engineering pertaining to design and fabrication of low-cost transition metal catalysts for large-current water splitting.
基金This work was funded by NIH grants R01EB020062(M.I.M.),R01NS102670(M.I.M.)U19AG033655.
文摘If the 20th century was the age of mapping and controlling the external world,the 21st century is the biomedical age of mapping and controlling the biological internal world.The biomedical age is bringing new technological breakthroughs for sensing and controlling human biomolecules,cells,tissues,and organs,which underpin new frontiers in the biomedical discovery,data,biomanufacturing,and translational sciences.This article reviews what we believe will be the next wave of biomedical engineering(BME)education in support of the biomedical age,what we have termed BME 2.0.BME 2.0 was announced on October 122017 at BMES 49(https://www.bme.jhu.edu/news-events/news/miller-opens-2017-bmes-annual-meeting-with-vision-for-new-bme-era/).We present several principles upon which we believe the BME 2.0 curriculum should be constructed,and from these principles,we describe what view as the foundations that form the next generations of curricula in support of the BME enterprise.The core principles of BME 2.0 education are(a)educate students bilingually,from day 1,in the languages of modern molecular biology and the analytical modeling of complex biological systems;(b)prepare every student to be a biomedical data scientist;(c)build a unique BME community for discovery and innovation via a vertically integrated and convergent learning environment spanning the university and hospital systems;(d)champion an educational culture of inclusive excellence;and(e)codify in the curriculum ongoing discoveries at the frontiers of the discipline,thus ensuring BME 2.0 as a launchpad for training the future leaders of the biotechnology marketplaces.We envision that the BME 2.0 education is the path for providing every student with the training to lead in this new era of engineering the future of medicine in the 21st century.
基金We acknowledge the funding support from UK Engineering and Physical Sciences Research Council （EPSRC） on the Doctoral Prize Fellowship （Grant No. EP/N509760/1） for IH and the EngD studentship （Grant No. EP/L015595/1） for JL. JZS is funded by Overseas Scholarship Council and Ministry of Education in China. We also acknowledge the funding support from China-UK Research and Innovation Partnership Fund： Newton Fund Ph.D. placement programme. We thank the National Natural Science Foundation of China （No. 21534007）, and the Beijing Municipal Science ＆ Technology Commission for their financial support.
文摘The therapeutic replacement of diseased tubular tissue is hindered by the availability and suitability of current donor, autologous and synthetically derived protheses. Artificially created, tissue engineered, constructs have the potential to alleviate these concerns with reduced autoimmune response, high anatomical accuracy, long-term patency and growth potential. The advent of 3D bioprinting technology has further supplemented the technological toolbox, opening up new biofabrication research opportunities and expanding the therapeutic potential of the field. In this review, we highlight the challenges facing those seeking to create artificial tubular tissue with its associated complex macro- and microscopic architecture. Current biofabrication approaches, including 3D printing techniques, are reviewed and future directions suggested.
基金supported by grants from the Natural Science Foundation of Tianjin(General Program),Nos.23JCYBJC01390(to RL),22JCYBJC00220(to XC),and 22JCYBJC00210(to QL).
文摘Peripheral nerve injury is a common neurological condition that often leads to severe functional limitations and disabilities.Research on the pathogenesis of peripheral nerve injury has focused on pathological changes at individual injury sites,neglecting multilevel pathological analysis of the overall nervous system and target organs.This has led to restrictions on current therapeutic approaches.In this paper,we first summarize the potential mechanisms of peripheral nerve injury from a holistic perspective,covering the central nervous system,peripheral nervous system,and target organs.After peripheral nerve injury,the cortical plasticity of the brain is altered due to damage to and regeneration of peripheral nerves;changes such as neuronal apoptosis and axonal demyelination occur in the spinal cord.The nerve will undergo axonal regeneration,activation of Schwann cells,inflammatory response,and vascular system regeneration at the injury site.Corresponding damage to target organs can occur,including skeletal muscle atrophy and sensory receptor disruption.We then provide a brief review of the research advances in therapeutic approaches to peripheral nerve injury.The main current treatments are conducted passively and include physical factor rehabilitation,pharmacological treatments,cell-based therapies,and physical exercise.However,most treatments only partially address the problem and cannot complete the systematic recovery of the entire central nervous system-peripheral nervous system-target organ pathway.Therefore,we should further explore multilevel treatment options that produce effective,long-lasting results,perhaps requiring a combination of passive(traditional)and active(novel)treatment methods to stimulate rehabilitation at the central-peripheral-target organ levels to achieve better functional recovery.
文摘Tissue engineering’s main goal is to regenerate or replace tissues or organs that have been destroyed by disease,injury,or congenital disabilities.Tissue engineering now uses artificial supporting structures called scaffolds to restore damaged tissues and organs.These are utilized to attach the right cells and then grow them.Rapid prototyping appears to be the most promising technology due to its high level of precision and control.Bone tissue replacement“scaffolding”is a common theme discussed in this article.The fused deposition technique was used to construct our scaffold,and a polymer called polylactic acids and soybean oil resin were used to construct our samples.The samples were then divided into two groups;the first group was left without immersion in the simulated body fluid and served as a control for comparison.The second group was immersed in the simulated body fluid.The results of the Field Emission Scanning Electron Microscope(FESEM),Energy Dispersive X-ray Spectroscopy(EDX)and X-ray diffraction(XRD)were utilized to interpret the surface attachment to ions,elements,and compounds,giving us a new perspective on scaffold architecture.In this study,an innovative method has been used to print therapeutic scaffold that combines fused deposition three-dimensional printing with ultraviolet curing to create a high-quality biodegradable polymeric scaffold.Finally,the results demonstrate that adding soybean oil resin to the PLA increased ion attachment to the surface while also attracting tricalcium phosphate formation on the surface of the scaffold,which is highly promising in bone tissue replacement.In conclusion,the soybean oil resin,which is new in the field of bone tissue engineering,shows magnificent characteristics and is a good replacement biopolymer that replaces many ceramic and polymeric materials used in this field that have poor morphological characteristics.
文摘The brain is one of the most important organs in a biological body which can only work in a relatively stable temperature range. However, many environmental factors in biosphere would cause cerebral temperature fluctuations. To sustain and regulate the brain temperature, many mechanisms of biological brain cooling have been evolved, including Selective Brain Cooling （SBC）, cooling through surface water evaporation, respiration, behavior response and using special anatomical ap- pendages. This article is dedicated to present a summarization and systematic interpretation on brain cooling strategies devel- oped in animals by classifying and comparatively analyzing each typical biological brain cooling mechanism from the per- spective of bio-heat transfer. Meanwhile, inspirations from such cooling in nature were proposed for developing advanced bionic engineering technologies especially with two focuses on therapeutic hypothermia and computer chip cooling areas. It is expected that many innovations can be achieved along this way to find out new cooling methodologies for a wide variety of industrial applications which will be highly efficient, energy saving, flexible or even intelligent.
文摘Engineered cardiac constructs(ECC)aid in the progression of regenerative medicine,disease modeling and targeted drug delivery to adjust and aim the release of remedial combination as well as decrease the side effects of drugs.In this research,polycaprolactone/gold nanoparticles(PCL/GNPs)three-dimensional(3D)composite scaffolds were manufactured by 3D printing using the fused deposition modeling(FDM)method and then coated with gelatin/spironolactone(GEL/SPL).Scanning electron microscopy(SEM)and Fourier transform-infrared spectroscopy(FTIR–ATR)were applied to characterize the samples.Furthermore,drug release,biodegradation,behavior of the myoblasts(H9C2)cell line,and cytotoxicity of the 3D scaffolds were evaluated.The microstructural observation of the scaffolds reported interconnected pores with 150–300µm in diameter.The 3D scaffolds were degraded significantly after 28 days of immersion in stimulated body fluid(SBF),with the maximum rate of GEL-coated 3D scaffolds.SPL release from cross-linked GEL coating demonstrated the excess of drug release over time,and according to the control release systems,the drug delivery systems(DDS)went into balance after the 14th day.In addition,cell culture study showed that with the addition of GNPs,the proliferation of(H9C2)was enhanced,and with GEL/SPL coating the cell attachment and viability were improved significantly.These findings suggested that PCL/GNPs 3D scaffolds coated with GEL/SPL can be an appropriate choice for myocardial tissue engineering.
文摘In the article“BME 2.0:Engineering the Future of Medicine”[1],the competing interests statement was inadvertently omitted by the publisher from the published version of the article.This has now been corrected in the PDF and HTML(full text).
