A novel highly porous 3-D poly（e-caprolactone） （PCL） scaffold with micro-channels was fabricated by injection molding and diluent acetic acids leaching technologies. In this study, the chitosan fiber was employed ...A novel highly porous 3-D poly（e-caprolactone） （PCL） scaffold with micro-channels was fabricated by injection molding and diluent acetic acids leaching technologies. In this study, the chitosan fiber was employed to form the microchannel in PCL matrix. The morphology, porosity and mechanical properties of the scaffolds were studied and calculated. It was found that the larger the content of chitosan fiber is, the higher the porosity would be, due to the volumetric expansion of chitosan fiber in PCL matrix during it being leached. In addition, the less the content of chitosan fiber is, the higher the compressive modulus would be.展开更多
It is known that the body can efficiently repair hard tissue (bone) micro fractures by suturing the defect through the deposition of minerals resulting in an area that is stronger post-injury. Larger defects, however,...It is known that the body can efficiently repair hard tissue (bone) micro fractures by suturing the defect through the deposition of minerals resulting in an area that is stronger post-injury. Larger defects, however, generally cause more trouble since the body is incapable of repairing them. Bone defects can occur as a result of congenital abnormalities, trauma, or disease. Traditional methods for addressing these defects have involved the use of acellular cadaverous bone or autologous bone. Both contain innate prob- lems associated with them;the former method can result in disease transmission, as well as very low integration with the host due to the lack of viable cells while the latter is associated with two surgical sites and morbidity at the donor site. Alternative methods have been developed, but no method has yet provided a satisfactory solution. As a result, resear- chers and the medical community are turning toward the promising fields of biomaterial development and tissue engineering to develop new materials and me- thods of bone regeneration. In this work, a design of experiments (DOE) approach was performed to ren- der commercially available biodegradable polymers (Poly(caprolactone)-diol/triol) photocrosslinkable and resultantly manufacturable using stereolithography (SL), a rapid prototyping technology. To perform the investigations, a commercial SL system (Viper HA, 3D Systems, Valencia, CA) equipped with a solid state laser system (355 nm wavelength) was used to manu-facture synthesized poly(caprolactone) trifuma- rate (PCLtF) 3D porous constructs. Results of the work conducted produced constructs which provided pro- mising chemical and biological results for the in- tended application.展开更多
Bone tissue engineering aims to use biodegrade able scaffolds to replace damaged tissue. This scaffold must be gradually degraded and replaced by tissue as similar as possible to the original one. In this work a hybri...Bone tissue engineering aims to use biodegrade able scaffolds to replace damaged tissue. This scaffold must be gradually degraded and replaced by tissue as similar as possible to the original one. In this work a hybrid porous scaffold containing chitosan, polyvinyl alcohol and bioactive glass was successfully obtained and subsequently characterized by scanning electron microscopy. The scaffold presented satisfactory pore size range and open interconnected pores, which are essential for tissue ingrowth. A cytotoxicity assay showed that this biomaterial allows adequate cell viability, so that it was considered suitable for an in vivo experiment. Promising results were obtained with the implant of the scaffold in an experimental model of a New Zealand rabbit femur bone lesion. Clinical and biochemical parameters measured such as complete blood count, total serum proteins, albumin, alanine aminotransferase and aspartate aminotransferase were similar between animals in the control group at all time periods studied. Histological and histometric studies showed that the scaffold was coated with a cement-like substance, exhibiting many areas of mineralized structures. Very few osteocyte-like cells or lining-like cells were found inside the amorphous mineralized deposit. In vivo results allow us to consider this scaffold as a promising biomaterial to be applied in bone tissue engineering.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
Porous metals fabricated via three-dimensional(3D)printing have attracted extensive attention in many fields owing to their open pores and customization potential.However,dense internal structures produced by the powd...Porous metals fabricated via three-dimensional(3D)printing have attracted extensive attention in many fields owing to their open pores and customization potential.However,dense internal structures produced by the powder bed fusion technique fails to meet the feature of porous materials in scenarios that demand large specific surface areas.Herein,we propose a strategy for 3D printing of titanium scaffolds featuring multiscale porous internal structures via powder modification and digital light processing(DLP).After modification,the titanium powders were composited with acrylic resin and maintained spherical shapes.Compared with the raw powder slurries,the modified powder slurries exhibited higher stability and preferable curing characteristics,and the depth sensitivity of the modified powder slurries with 45 vol%solid loading increased by approximately 72%.Green scaffolds were subsequently printed from the slurries with a solid loading reaching 45 vol%via DLP 3D printing.The scaffolds had macropores(pore diameters of approximately 1 mm)and internal open micropores(pore diameters of approximately 5.7-13.0μm)after sintering.Additionally,these small-featured(approximately 320μm)scaffolds retained sufficient compressive strength((70.01±3.53)MPa)even with high porosity(approximately 73.95%).This work can facilitate the fabrication of multiscale porous metal scaffolds with high solid loading slurries,offering potential for applications requiring high specific surface area ratios.展开更多
Recent advances in bone regeneration have introduced the concept of four-dimensional(4D)scaffolds that can undergo morphological and functional changes in response to external stimuli.While several studies have propos...Recent advances in bone regeneration have introduced the concept of four-dimensional(4D)scaffolds that can undergo morphological and functional changes in response to external stimuli.While several studies have proposed patient-specific designs for defect sites,they often fail to adequately distinguish the advantages of 4D scaffolds over conventional 3D counterparts.This study aimed to investigate the potential benefits of 4D scaffolds in clinically challenging scenarios involving curved defects,where fixation is difficult.We proposed the use of Shape-Memory Polymers(SMPs)as a solution to address critical issues in personalized scaffold fabrication,including dimensional accuracy,measurement error,and manufacturing imprecision.Experimental results demonstrated that the Curved-Layer Fused Deposition Modeling(CLFDM)scaffold,which offers superior conformability to curved defects,achieved significantly higher interfacial contact with the defect area compared to traditional Fused Deposition Modeling(FDM)scaffolds.Specifically,the CLFDM scaffold facilitated bone regeneration of 25.59±4.72 mm^(3),which is more than twice the 9.37±1.36 mm^(3)observed with the 3D FDM scaffold.Furthermore,the 4D CLFDM scaffold achieved 75.38±11.65 mm^(3)of new bone formation after four weeks,approximately three times greater than that of the 3D CLFDM scaffold,regardless of surface micro-roughness.These results underscore that improved geometrical conformity between the scaffold and the defect site enhances cellular infiltration and contributes to more effective bone regeneration.The findings also highlight the promise of 4D scaffolds as a compelling strategy to overcome geometric and dimensional mismatches in the design of patient-specific scaffolds.展开更多
Bone repair remains an important target in tissue engineering,making the development of bioactive scaffolds for effective bone defect repair a critical objective.In this study,β-tricalcium phosphate(β-TCP)scaffolds ...Bone repair remains an important target in tissue engineering,making the development of bioactive scaffolds for effective bone defect repair a critical objective.In this study,β-tricalcium phosphate(β-TCP)scaffolds incorporated with processed pyritum decoction(PPD)were fabricated using three-dimensional(3D)printing-assisted freeze-casting.The produced composite scaffolds were evaluated for their mechanical strength,physicochemical properties,biocompatibility,in vitro proangiogenic activity,and in vivo efficacy in repairing rabbit femoral defects.They not only demonstrated excellent physicochemical properties,enhanced mechanical strength,and good biosafety but also significantly promoted the proliferation,migration,and aggregation of pro-angiogenic human umbilical vein endothelial cells(HUVECs).In vivo studies revealed that all scaffold groups facilitated osteogenesis at the bone defect site,with theβ-TCP scaffolds loaded with PPD markedly enhancing the expression of neurogenic locus Notch homolog protein 1(Notch1),vascular endothelial growth factor(VEGF),bone morphogenetic protein-2(BMP-2),and osteopontin(OPN).Overall,the scaffolds developed in this study exhibited strong angiogenic and osteogenic capabilities both in vitro and in vivo.The incorporation of PPD notably promoted the angiogenic-osteogenic coupling,thereby accelerating bone repair,which suggests that PPD is a promising material for bone repair and that the PPD/β-TCP scaffolds hold great potential as a bone graft alternative.展开更多
Osteonecrosis,which is typically induced by trauma,glucocorticoid abuse,or alcoholism,is one of the most severe diseases in clinical orthopedics.Osteonecrosis often leads to joint destruction,and arthroplasty is event...Osteonecrosis,which is typically induced by trauma,glucocorticoid abuse,or alcoholism,is one of the most severe diseases in clinical orthopedics.Osteonecrosis often leads to joint destruction,and arthroplasty is eventually required.Enhancement of bone regeneration is a critical management strategy employed in osteonecrosis therapy.Bone tissue engineering based on engineered three-dimensional(3D)scaffolds with appropriate architecture and osteoconductive activity,alone or functionalized with bioactive factors,have been developed to enhance bone regeneration in osteonecrosis.In this review,we elaborate on the ideal properties of 3D scaffolds for enhanced bone regeneration in osteonecrosis,including biocompatibility,degradability,porosity,and mechanical performance.In addition,we summarize the development of 3D scaffolds alone or functionalized with bioactive factors for accelerating bone regeneration in osteonecrosis and discuss their prospects for translation to clinical practice.展开更多
Mesenchymal stem cells （MSCs） show the great promise for the treatment of a variety of diseases because of their self-renewal and multipotential abilities. MSCs are generally cultured on two-dimensional （2D） subst...Mesenchymal stem cells （MSCs） show the great promise for the treatment of a variety of diseases because of their self-renewal and multipotential abilities. MSCs are generally cultured on two-dimensional （2D） substrate in vitro. There are indications that they may simultaneously lose their sternness and multipotentiality as the result of prolonged 2D culture. In this study, we used three-dimensional （3D） collagen scaffolds as rat MSCs cartier and compared the properties of MSCs on 3D collagen scaffolds with monolayer cultured MSCs. The results demonstrated that collagen scaffolds were suitable for rat MSCs adherence and proliferation. More importantly, compared to MSCs under 2D culture, 3D MSCs significantly maintained higher expression levels of stemness genes （Oct4, Sox2, Rex-1 and Nanog）, yielded high frequencies of colony-forming units-fibroblastic （CFU-F） and showed enhanced osteogenic and adipogenic differentiation efficiency upon induction. Thus, 3D collagen scaffolds may be beneficial for expanding rat MSCs while maintaining the stem cell properties in vitro.展开更多
This study aimed to examine the differences in the morphological properties and proliferation of olfactory ensheathing cells in three-dimensional culture on collagen-heparan sulfate biological scaffolds and in two-dim...This study aimed to examine the differences in the morphological properties and proliferation of olfactory ensheathing cells in three-dimensional culture on collagen-heparan sulfate biological scaffolds and in two-dimensional culture on common flat culture plates. The proliferation rate of olfactory ensheathing cells in three-dimensional culture was higher than that in two-dimensional culture, as detected by an M-I-r assay. In addition, more than half of the olfactory ensheathing cells subcultured using the trypsinization method in three-dimensional culture displayed a spindly Schwann cell-like morphology with extremely long processes, while they showed a flat astrocyte-like morphology in two-dimensional culture. Moreover, spindle-shaped olfactory ensheathing cells tended to adopt an elongated bipolar morphology under both culture conditions. Experimental findings indicate that the morphological properties and proliferation of olfactory ensheathing cells in three-dimensional culture on collagen-heparan sulfate biological scaffolds are better than those in two-dimensional culture.展开更多
Conventional fabrication methods lack the ability to control both macro- and micro-structures of generated scaffolds. Three-dimensional printing is a solid free-form fabrication method that provides novel ways to crea...Conventional fabrication methods lack the ability to control both macro- and micro-structures of generated scaffolds. Three-dimensional printing is a solid free-form fabrication method that provides novel ways to create customized scaffolds with high precision and accuracy. In this study, an electrically controlled cortical impactor was used to induce randomized brain tissue defects. The overall shape of scaffolds was designed using rat-specific anatomical data obtained from magnetic resonance imaging, and the internal structure was created by computer- aided design. As the result of limitations arising from insufficient resolution of the manufacturing process, we magnified the size of the cavity model prototype five-fold to successfully fabricate customized collagen-chitosan scaffolds using three-dimensional printing. Results demonstrated that scaffolds have three-dimensional porous structures, high porosity, highly specific surface areas, pore connectivity and good internal characteristics. Neural stem cells co-cultured with scaffolds showed good viability, indicating good biocompatibility and biodegradability. This technique may be a promising new strategy for regenerating complex damaged brain tissues, and helps pave the way toward personalized medicine.展开更多
Many studies have shown that bio-scaffolds have important value for promoting axonal regeneration of injured spinal cord.Indeed,cell transplantation and bio-scaffold implantation are considered to be effective methods...Many studies have shown that bio-scaffolds have important value for promoting axonal regeneration of injured spinal cord.Indeed,cell transplantation and bio-scaffold implantation are considered to be effective methods for neural regeneration.This study was designed to fabricate a type of three-dimensional collagen/silk fibroin scaffold (3D-CF) with cavities that simulate the anatomy of normal spinal cord.This scaffold allows cell growth in vitro and in vivo.To observe the effects of combined transplantation of neural stem cells (NSCs) and 3D-CF on the repair of spinal cord injury.Forty Sprague-Dawley rats were divided into four groups: sham (only laminectomy was performed),spinal cord injury (transection injury of T10 spinal cord without any transplantation),3D-CF (3D scaffold was transplanted into the local injured cavity),and 3D-CF + NSCs (3D scaffold co-cultured with NSCs was transplanted into the local injured cavity.Neuroelectrophysiology,imaging,hematoxylin-eosin staining,argentaffin staining,immunofluorescence staining,and western blot assay were performed.Apart from the sham group,neurological scores were significantly higher in the 3D-CF + NSCs group compared with other groups.Moreover,latency of the 3D-CF + NSCs group was significantly reduced,while the amplitude was significantly increased in motor evoked potential tests.The results of magnetic resonance imaging and diffusion tensor imaging showed that both spinal cord continuity and the filling of injury cavity were the best in the 3D-CF + NSCs group.Moreover,regenerative axons were abundant and glial scarring was reduced in the 3D-CF + NSCs group compared with other groups.These results confirm that implantation of 3D-CF combined with NSCs can promote the repair of injured spinal cord.This study was approved by the Institutional Animal Care and Use Committee of People’s Armed Police Force Medical Center in 2017 (approval No.2017-0007.2).展开更多
Collagen protein is an ideal scaffold material for the transplantation of neural stem cells. In this study rat neural stern cells were seeded into a three-dimensional collagen gel scaffold, with suspension cultured ne...Collagen protein is an ideal scaffold material for the transplantation of neural stem cells. In this study rat neural stern cells were seeded into a three-dimensional collagen gel scaffold, with suspension cultured neural stem cells being used as a control group. Neural stem cells, which were cultured in medium containing epidermal growth factor and basic fibroblast growth factor, actively expanded and formed neurospheres in both culture groups. In serum-free medium conditions, the processes extended from neurospheres in the collagen gel group were much longer than those in the suspension culture group. Immunofluorescence staining showed that neurespheres cultured in collagen gels were stained positive for nestin and differentiated cells were stained positive for the neuronal marker βIII-tubulin, the astrocytic marker glial fibrillary acidic protein and the oligodendrocytic marker 2＇,3＇-cyclic nucleotide 3＇-phosphodiesterase. Compared with neurospheres cultured in suspension, the differentiation potential of neural stem cells cultured in collagen gels increased, with the formation of neurons at an early stage. Our results show that the three-dimensional collagen gel culture system is superior to suspension culture in the proliferation, differentiation and process outgrowth of neural stem cells.展开更多
Three-dimensional(3D)urban structures play a critical role in informing climate mitigation strategies aimed at the built environment and facilitating sustainable urban development.Regrettably,there exists a significan...Three-dimensional(3D)urban structures play a critical role in informing climate mitigation strategies aimed at the built environment and facilitating sustainable urban development.Regrettably,there exists a significant gap in detailed and consistent data on 3D building space structures with global coverage due to the challenges inherent in the data collection and model calibration processes.In this study,we constructed a global urban structure(GUS-3D)dataset,including building volume,height,and footprint information,at a 500 m spatial resolution using extensive satellite observation products and numerous reference building samples.Our analysis indicated that the total volume of buildings worldwide in2015 exceeded 1×10^(12)m^(3).Over the 1985 to 2015 period,we observed a slight increase in the magnitude of 3D building volume growth(i.e.,it increased from 166.02 km3 during the 1985–2000 period to 175.08km3 during the 2000–2015 period),while the expansion magnitudes of the two-dimensional(2D)building footprint(22.51×10^(3) vs 13.29×10^(3)km^(2))and urban extent(157×10^(3) vs 133.8×10^(3)km^(2))notably decreased.This trend highlights the significant increase in intensive vertical utilization of urban land.Furthermore,we identified significant heterogeneity in building space provision and inequality across cities worldwide.This inequality is particularly pronounced in many populous Asian cities,which has been overlooked in previous studies on economic inequality.The GUS-3D dataset shows great potential to deepen our understanding of the urban environment and creates new horizons for numerous 3D urban studies.展开更多
To address the problem of multi-missile cooperative interception against maneuvering targets at a prespecified impact time and desired Line-of-Sight(LOS)angles in ThreeDimensional(3D)space,this paper proposes a 3D lea...To address the problem of multi-missile cooperative interception against maneuvering targets at a prespecified impact time and desired Line-of-Sight(LOS)angles in ThreeDimensional(3D)space,this paper proposes a 3D leader-following cooperative interception guidance law.First,in the LOS direction of the leader,an impact time-controlled guidance law is derived based on the fixed-time stability theory,which enables the leader to complete the interception task at a prespecified impact time.Next,in the LOS direction of the followers,by introducing a time consensus tracking error function,a fixed-time consensus tracking guidance law is investigated to guarantee the consensus tracking convergence of the time-to-go.Then,in the direction normal to the LOS,by combining the designed global integral sliding mode surface and the second-order Sliding Mode Control(SMC)theory,an innovative 3D LOS-angle-constrained interception guidance law is developed,which eliminates the reaching phase in the traditional sliding mode guidance laws and effectively saves energy consumption.Moreover,it effectively suppresses the chattering phenomenon while avoiding the singularity issue,and compensates for unknown interference caused by target maneuvering online,making it convenient for practical engineering applications.Finally,theoretical proof analysis and multiple sets of numerical simulation results verify the effectiveness,superiority,and robustness of the investigated guidance law.展开更多
Objective:Squamous cell carcinoma(SCC)represents the most common histotype of all head and neck malignancies and includes oropharyngeal squamous cell carcinoma(OSCC),a tumor associated with different clinical outcomes...Objective:Squamous cell carcinoma(SCC)represents the most common histotype of all head and neck malignancies and includes oropharyngeal squamous cell carcinoma(OSCC),a tumor associated with different clinical outcomes and linked to human papilloma virus(HPV)status.Translational research has few available in vitro models with which to study the different pathophysiological behavior of OSCCs.The present study proposes a 3-dimensional(3 D)biomimetic collagen-based scaffold to mimic the tumor microenvironment and the crosstalk between the extracellular matrix(ECM)and cancer cells.Methods:We compared the phenotypic and genetic features of HPV-positive and HPV-negative OSCC cell lines cultured on common monolayer supports and on scaffolds.We also explored cancer cell adaptation to the 3 D microenvironment and its impact on the efficacy of drugs tested on cell lines and primary cultures.Results:HPV-positive and HPV-negative cell lines were successfully grown in the 3 D model and displayed different collagen fiber organization.The 3 D cultures induced an increased expression of markers related to epithelial–mesenchymal transition(EMT)and to matrix interactions and showed different migration behavior,as confirmed by zebrafish embryo xenografts.The expression of hypoxia-inducible factor 1α(1α)and glycolysis markers were indicative of the development of a hypoxic microenvironment inside the scaffold area.Furthermore,the 3 D cultures activated drug-resistance signaling pathways in both cell lines and primary cultures.Conclusions:Our results suggest that collagen-based scaffolds could be a suitable model for the reproduction of the pathophysiological features of OSCCs.Moreover,3 D architecture appears capable of inducing drug-resistance processes that can be studied to better our understanding of the different clinical outcomes of HPV-positive and HPV-negative patients with OSCCs.展开更多
Osteoconductive function is remarkably low in bone disease in the absence of bone tissue surrounding the grafting site,or if the bone tissue is in poor condition.Thus,an effective bone graft in terms of both osteocond...Osteoconductive function is remarkably low in bone disease in the absence of bone tissue surrounding the grafting site,or if the bone tissue is in poor condition.Thus,an effective bone graft in terms of both osteoconductivity and osteoinductivity is required for clinical therapy.Recently,the three-dimensional(3D)kagome structure has been shown to be advantageous for bone tissue regeneration due to its mechanical properties.In this study,a polycaprolactone(PCL)kagome-structure scaffold containing a hyaluronic acid(HA)-based hydrogel was fabricated using a 3D printing technique.The retention capacity of the hydrogel in the scaffold was assessed in vivo with a rat calvaria subcutaneous model for 3 weeks,and the results were compared with those obtained with conventional 3D-printed PCL grid-structure scaffolds containing HA-based hydrogel and bulk-type HA-based hydrogel.The retained hydrogel in the kagome-structure scaffold was further evaluated by in vivo imaging system analysis.To further reinforce the osteoinductivity of the kagome-structure scaffold,a PCL kagome-structure scaffold with bone morphogenetic protein-2(BMP-2)containing HA hydrogel was fabricated and implanted in a calvarial defect model of rabbits for 16 weeks.The bone regeneration characteristics were evaluated with hematoxylin and eosin(H&E),Masson’s trichrome staining,and micro-CT image analysis.展开更多
In this work, patterned macropores with a diameter larger than 100 μm were introduced to pristine three-dimensional (3D) nanofibrous bacterial cellulose (BC) scaffolds by using the infrared laser micromachining techn...In this work, patterned macropores with a diameter larger than 100 μm were introduced to pristine three-dimensional (3D) nanofibrous bacterial cellulose (BC) scaffolds by using the infrared laser micromachining technique in an attempt to create an in vitro model for the culture of breast cancer cells. The morphology, pore structure, and mechanical performance of the obtained patterned macroporous BC (PM-BC) scaffolds were characterized by scanning electron microscopy (SEM), mercury intrusion porosimeter, and mechanical testing. A human breast cancer cell (MDA-MB-231) line was cultured onto the PM-BC scaffolds to investigate the role of macropores in the control of cancer cell behavior. MTT assay, SEM, and hematoxylin and eosin (H&E) staining were employed to determine cell adhesion, growth, proliferation, and infiltration. The PM-BC scaffolds were found to be able to promote cellular adhesion and proliferation on the scaffolds, and further to allow for cell infiltration into the PM-BC scaffolds. The results demonstrated that BC scaffolds with laser-patterned macropores were promising for the in vitro 3D culture of breast cancer cells.展开更多
BACKGROUND Cardiovascular diseases are the major cause of mortality worldwide.Regeneration of the damaged myocardium remains a challenge due to mechanical constraints and limited healing ability of the adult heart tis...BACKGROUND Cardiovascular diseases are the major cause of mortality worldwide.Regeneration of the damaged myocardium remains a challenge due to mechanical constraints and limited healing ability of the adult heart tissue.Cardiac tissue engineering using biomaterial scaffolds combined with stem cells and bioactive molecules could be a highly promising approach for cardiac repair.Use of biomaterials can provide suitable microenvironment to the cells and can solve cell engraftment problems associated with cell transplantation alone.Mesenchymal stem cells(MSCs)are potential candidates in cardiac tissue engineering because of their multilineage differentiation potential and ease of isolation.Use of DNA methyl transferase inhibitor,such as zebularine,in combination with three-dimensional(3D)scaffold can promote efficient MSC differentiation into cardiac lineage,as epigenetic modifications play a fundamental role in determining cell fate and lineage specific gene expression.AIM To investigate the role of collagen scaffold and zebularine in the differentiation of rat bone marrow(BM)-MSCs and their subsequent in vivo effects.METHODS MSCs were isolated from rat BM and characterized morphologically,immunophenotypically and by multilineage differentiation potential.MSCs were seeded in collagen scaffold and treated with 3μmol/L zebularine in three different ways.Cytotoxicity analysis was done and cardiac differentiation was analyzed at the gene and protein levels.Treated and untreated MSC-seeded scaffolds were transplanted in the rat myocardial infarction(MI)model and cardiac function was assessed by echocardiography.Cell tracking was performed by DiI dye labeling,while regeneration and neovascularization were evaluated by histological and immunohistochemical analysis,respectively.RESULTS MSCs were successfully isolated and seeded in collagen scaffold.Cytotoxicity analysis revealed that zebularine was not cytotoxic in any of the treatment groups.Cardiac differentiation analysis showed more pronounced results in the type 3 treatment group which was subsequently chosen for the transplantation in the in vivo MI model.Significant improvement in cardiac function was observed in the zebularine treated MSC-seeded scaffold group as compared to the MI control.Histological analysis also showed reduction in fibrotic scar,improvement in left ventricular wall thickness and preservation of ventricular remodeling in the zebularine treated MSC-seeded scaffold group.Immunohistochemical analysis revealed significant expression of cardiac proteins in DiI labeled transplanted cells and a significant increase in the number of blood vessels in the zebularine treated MSC-seeded collagen scaffold transplanted group.CONCLUSION Combination of 3D collagen scaffold and zebularine treatment enhances cardiac differentiation potential of MSCs,improves cell engraftment at the infarcted region,reduces infarct size and improves cardiac function.展开更多
Liposarcoma is one of the most common soft tissue sarcomas,however,its occurrence rate is still rare compared to other cancers.Due to its rarity,in vitro experiments are an essential approach to elucidate liposarcoma ...Liposarcoma is one of the most common soft tissue sarcomas,however,its occurrence rate is still rare compared to other cancers.Due to its rarity,in vitro experiments are an essential approach to elucidate liposarcoma pathobiology.Conventional cell culture-based research(2D cell culture)is still playing a pivotal role,while several shortcomings have been recently under discussion.In vivo,mouse models are usually adopted for pre-clinical analyses with expectations to overcome the issues of 2D cell culture.However,they do not fully recapitulate human dedifferentiated liposarcoma(DDLPS)characteristics.Therefore,three-dimensional(3D)culture systems have been the recent research focus in the cell biology field with the expectation to overcome at the same time the disadvantages of 2D cell culture and in vivo animal models and fill in the gap between them.Given the liposarcoma rarity,we believe that 3D cell culture techniques,including 3D cell cultures/co-cultures,and Patient-Derived tumor Organoids(PDOs),represent a promising approach to facilitate liposarcoma investigation and elucidate its molecular mechanisms and effective therapy development.In this review,we first provide a general overview of 3D cell cultures compared to 2D cell cultures.We then focus on one of the recent 3D cell culture applications,Patient-Derived Organoids(PDOs),summarizing and discussing several PDO methodologies.Finally,we discuss the current and future applications of PDOs to sarcoma,particularly in the field of liposarcoma.展开更多
基金financially supported by the China Scholarship Council and the Wisconsin Institute for Discovery(WID),that enabled the authors to perform this research at the University of Wisconsin-Madison,the National Natural Science Foundation of China(No.51303027)the Scientific Research Staring Foundation,Fujian University of Technology,China(No.GY-Z13028)
文摘A novel highly porous 3-D poly（e-caprolactone） （PCL） scaffold with micro-channels was fabricated by injection molding and diluent acetic acids leaching technologies. In this study, the chitosan fiber was employed to form the microchannel in PCL matrix. The morphology, porosity and mechanical properties of the scaffolds were studied and calculated. It was found that the larger the content of chitosan fiber is, the higher the porosity would be, due to the volumetric expansion of chitosan fiber in PCL matrix during it being leached. In addition, the less the content of chitosan fiber is, the higher the compressive modulus would be.
文摘It is known that the body can efficiently repair hard tissue (bone) micro fractures by suturing the defect through the deposition of minerals resulting in an area that is stronger post-injury. Larger defects, however, generally cause more trouble since the body is incapable of repairing them. Bone defects can occur as a result of congenital abnormalities, trauma, or disease. Traditional methods for addressing these defects have involved the use of acellular cadaverous bone or autologous bone. Both contain innate prob- lems associated with them;the former method can result in disease transmission, as well as very low integration with the host due to the lack of viable cells while the latter is associated with two surgical sites and morbidity at the donor site. Alternative methods have been developed, but no method has yet provided a satisfactory solution. As a result, resear- chers and the medical community are turning toward the promising fields of biomaterial development and tissue engineering to develop new materials and me- thods of bone regeneration. In this work, a design of experiments (DOE) approach was performed to ren- der commercially available biodegradable polymers (Poly(caprolactone)-diol/triol) photocrosslinkable and resultantly manufacturable using stereolithography (SL), a rapid prototyping technology. To perform the investigations, a commercial SL system (Viper HA, 3D Systems, Valencia, CA) equipped with a solid state laser system (355 nm wavelength) was used to manu-facture synthesized poly(caprolactone) trifuma- rate (PCLtF) 3D porous constructs. Results of the work conducted produced constructs which provided pro- mising chemical and biological results for the in- tended application.
文摘Bone tissue engineering aims to use biodegrade able scaffolds to replace damaged tissue. This scaffold must be gradually degraded and replaced by tissue as similar as possible to the original one. In this work a hybrid porous scaffold containing chitosan, polyvinyl alcohol and bioactive glass was successfully obtained and subsequently characterized by scanning electron microscopy. The scaffold presented satisfactory pore size range and open interconnected pores, which are essential for tissue ingrowth. A cytotoxicity assay showed that this biomaterial allows adequate cell viability, so that it was considered suitable for an in vivo experiment. Promising results were obtained with the implant of the scaffold in an experimental model of a New Zealand rabbit femur bone lesion. Clinical and biochemical parameters measured such as complete blood count, total serum proteins, albumin, alanine aminotransferase and aspartate aminotransferase were similar between animals in the control group at all time periods studied. Histological and histometric studies showed that the scaffold was coated with a cement-like substance, exhibiting many areas of mineralized structures. Very few osteocyte-like cells or lining-like cells were found inside the amorphous mineralized deposit. In vivo results allow us to consider this scaffold as a promising biomaterial to be applied in bone tissue engineering.
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.
基金supported by the National Natural Science Foundation of China(Nos.52405326,52105588 and 52075421)the Key Research and Development Program of Shaanxi(Nos.2024GX-YBXM-222 and 2023-YBSF-276)。
文摘Porous metals fabricated via three-dimensional(3D)printing have attracted extensive attention in many fields owing to their open pores and customization potential.However,dense internal structures produced by the powder bed fusion technique fails to meet the feature of porous materials in scenarios that demand large specific surface areas.Herein,we propose a strategy for 3D printing of titanium scaffolds featuring multiscale porous internal structures via powder modification and digital light processing(DLP).After modification,the titanium powders were composited with acrylic resin and maintained spherical shapes.Compared with the raw powder slurries,the modified powder slurries exhibited higher stability and preferable curing characteristics,and the depth sensitivity of the modified powder slurries with 45 vol%solid loading increased by approximately 72%.Green scaffolds were subsequently printed from the slurries with a solid loading reaching 45 vol%via DLP 3D printing.The scaffolds had macropores(pore diameters of approximately 1 mm)and internal open micropores(pore diameters of approximately 5.7-13.0μm)after sintering.Additionally,these small-featured(approximately 320μm)scaffolds retained sufficient compressive strength((70.01±3.53)MPa)even with high porosity(approximately 73.95%).This work can facilitate the fabrication of multiscale porous metal scaffolds with high solid loading slurries,offering potential for applications requiring high specific surface area ratios.
基金supported by the National Research Foundation of Korea(NRF)grant funded by the Korean government(MSIT)(No.NRF-2022R1A4A1028747 and RS-2024-00344151).
文摘Recent advances in bone regeneration have introduced the concept of four-dimensional(4D)scaffolds that can undergo morphological and functional changes in response to external stimuli.While several studies have proposed patient-specific designs for defect sites,they often fail to adequately distinguish the advantages of 4D scaffolds over conventional 3D counterparts.This study aimed to investigate the potential benefits of 4D scaffolds in clinically challenging scenarios involving curved defects,where fixation is difficult.We proposed the use of Shape-Memory Polymers(SMPs)as a solution to address critical issues in personalized scaffold fabrication,including dimensional accuracy,measurement error,and manufacturing imprecision.Experimental results demonstrated that the Curved-Layer Fused Deposition Modeling(CLFDM)scaffold,which offers superior conformability to curved defects,achieved significantly higher interfacial contact with the defect area compared to traditional Fused Deposition Modeling(FDM)scaffolds.Specifically,the CLFDM scaffold facilitated bone regeneration of 25.59±4.72 mm^(3),which is more than twice the 9.37±1.36 mm^(3)observed with the 3D FDM scaffold.Furthermore,the 4D CLFDM scaffold achieved 75.38±11.65 mm^(3)of new bone formation after four weeks,approximately three times greater than that of the 3D CLFDM scaffold,regardless of surface micro-roughness.These results underscore that improved geometrical conformity between the scaffold and the defect site enhances cellular infiltration and contributes to more effective bone regeneration.The findings also highlight the promise of 4D scaffolds as a compelling strategy to overcome geometric and dimensional mismatches in the design of patient-specific scaffolds.
基金supported by the National Science Foundation of China(Nos.81373970,81773902,81973484,and 32171402)the National College Students Innovation and Entrepreneurship Training Program(No.201810315019)+4 种基金the Postgraduate Research and Practice Innovation Program of Jiangsu Province(Nos.SJCX21_0712 and KYCX23_2052)the Scientific Research Project of Jiangsu Provincial Association of Traditional Chinese Medicine(No.XYLD2024013)the Youth Scientific Research Project of Jiangyin Municipal Health Commission(No.Q202402)the Natural Science Foundation Project of Nanjing University of Chinese Medicine(No.XZR2024173)the Jiangyin Science and Technology Innovation Special Fund Project(No.JY0603A011014230032PB),China.
文摘Bone repair remains an important target in tissue engineering,making the development of bioactive scaffolds for effective bone defect repair a critical objective.In this study,β-tricalcium phosphate(β-TCP)scaffolds incorporated with processed pyritum decoction(PPD)were fabricated using three-dimensional(3D)printing-assisted freeze-casting.The produced composite scaffolds were evaluated for their mechanical strength,physicochemical properties,biocompatibility,in vitro proangiogenic activity,and in vivo efficacy in repairing rabbit femoral defects.They not only demonstrated excellent physicochemical properties,enhanced mechanical strength,and good biosafety but also significantly promoted the proliferation,migration,and aggregation of pro-angiogenic human umbilical vein endothelial cells(HUVECs).In vivo studies revealed that all scaffold groups facilitated osteogenesis at the bone defect site,with theβ-TCP scaffolds loaded with PPD markedly enhancing the expression of neurogenic locus Notch homolog protein 1(Notch1),vascular endothelial growth factor(VEGF),bone morphogenetic protein-2(BMP-2),and osteopontin(OPN).Overall,the scaffolds developed in this study exhibited strong angiogenic and osteogenic capabilities both in vitro and in vivo.The incorporation of PPD notably promoted the angiogenic-osteogenic coupling,thereby accelerating bone repair,which suggests that PPD is a promising material for bone repair and that the PPD/β-TCP scaffolds hold great potential as a bone graft alternative.
基金financially supported by the National Natural Science Foundation of China(Grant Nos.51973216,51873207,51803006, 51833010)the Science and Technology Development Program of Jilin Province(Grant No.20190201068JC)+3 种基金the Youth Talents Promotion Project of Jilin Province(Grant No.181909)the Youth Innovation Promotion Association of the Chinese Academy of Sciences(Grant No.2019005)the Special Foundation for Provincial Authorities from Finance Department of Jilin Province(Grant No.3D518V313429)the State Key Laboratory of Advanced Technology for Materials Synthesis and Processing(Wuhan University of Technology)(Grant No.2020-KF-5).
文摘Osteonecrosis,which is typically induced by trauma,glucocorticoid abuse,or alcoholism,is one of the most severe diseases in clinical orthopedics.Osteonecrosis often leads to joint destruction,and arthroplasty is eventually required.Enhancement of bone regeneration is a critical management strategy employed in osteonecrosis therapy.Bone tissue engineering based on engineered three-dimensional(3D)scaffolds with appropriate architecture and osteoconductive activity,alone or functionalized with bioactive factors,have been developed to enhance bone regeneration in osteonecrosis.In this review,we elaborate on the ideal properties of 3D scaffolds for enhanced bone regeneration in osteonecrosis,including biocompatibility,degradability,porosity,and mechanical performance.In addition,we summarize the development of 3D scaffolds alone or functionalized with bioactive factors for accelerating bone regeneration in osteonecrosis and discuss their prospects for translation to clinical practice.
基金supported by the grants from the Ministry of Science and Technology of China(Nos.2011CB965001 and 2011CB710905)the Knowledge Innovation Program of the Chinese Academy of Sciences(Nos.KSCX2-YW-R-232, KJCX2-YW-L08 and KYQY-QN-015)
文摘Mesenchymal stem cells （MSCs） show the great promise for the treatment of a variety of diseases because of their self-renewal and multipotential abilities. MSCs are generally cultured on two-dimensional （2D） substrate in vitro. There are indications that they may simultaneously lose their sternness and multipotentiality as the result of prolonged 2D culture. In this study, we used three-dimensional （3D） collagen scaffolds as rat MSCs cartier and compared the properties of MSCs on 3D collagen scaffolds with monolayer cultured MSCs. The results demonstrated that collagen scaffolds were suitable for rat MSCs adherence and proliferation. More importantly, compared to MSCs under 2D culture, 3D MSCs significantly maintained higher expression levels of stemness genes （Oct4, Sox2, Rex-1 and Nanog）, yielded high frequencies of colony-forming units-fibroblastic （CFU-F） and showed enhanced osteogenic and adipogenic differentiation efficiency upon induction. Thus, 3D collagen scaffolds may be beneficial for expanding rat MSCs while maintaining the stem cell properties in vitro.
基金sponsored by the National Natural Science Foundation of China,No. 30570628,30770751 and 81171089
文摘This study aimed to examine the differences in the morphological properties and proliferation of olfactory ensheathing cells in three-dimensional culture on collagen-heparan sulfate biological scaffolds and in two-dimensional culture on common flat culture plates. The proliferation rate of olfactory ensheathing cells in three-dimensional culture was higher than that in two-dimensional culture, as detected by an M-I-r assay. In addition, more than half of the olfactory ensheathing cells subcultured using the trypsinization method in three-dimensional culture displayed a spindly Schwann cell-like morphology with extremely long processes, while they showed a flat astrocyte-like morphology in two-dimensional culture. Moreover, spindle-shaped olfactory ensheathing cells tended to adopt an elongated bipolar morphology under both culture conditions. Experimental findings indicate that the morphological properties and proliferation of olfactory ensheathing cells in three-dimensional culture on collagen-heparan sulfate biological scaffolds are better than those in two-dimensional culture.
基金supported by the National Natural Science Foundation of China,No.81301050,81401067,81271392,81471275,81541034the Natural Science Foundation of Tianjin City of China,No.14JCQNJC10200,15JCQNJC11100,16JCYBJC27600
文摘Conventional fabrication methods lack the ability to control both macro- and micro-structures of generated scaffolds. Three-dimensional printing is a solid free-form fabrication method that provides novel ways to create customized scaffolds with high precision and accuracy. In this study, an electrically controlled cortical impactor was used to induce randomized brain tissue defects. The overall shape of scaffolds was designed using rat-specific anatomical data obtained from magnetic resonance imaging, and the internal structure was created by computer- aided design. As the result of limitations arising from insufficient resolution of the manufacturing process, we magnified the size of the cavity model prototype five-fold to successfully fabricate customized collagen-chitosan scaffolds using three-dimensional printing. Results demonstrated that scaffolds have three-dimensional porous structures, high porosity, highly specific surface areas, pore connectivity and good internal characteristics. Neural stem cells co-cultured with scaffolds showed good viability, indicating good biocompatibility and biodegradability. This technique may be a promising new strategy for regenerating complex damaged brain tissues, and helps pave the way toward personalized medicine.
基金supported by the National Natural Science Foundation of China,No.11672332(to XYC)the National Key Research and Development Plan of China,No.2016YFC1101500(to SZ)
文摘Many studies have shown that bio-scaffolds have important value for promoting axonal regeneration of injured spinal cord.Indeed,cell transplantation and bio-scaffold implantation are considered to be effective methods for neural regeneration.This study was designed to fabricate a type of three-dimensional collagen/silk fibroin scaffold (3D-CF) with cavities that simulate the anatomy of normal spinal cord.This scaffold allows cell growth in vitro and in vivo.To observe the effects of combined transplantation of neural stem cells (NSCs) and 3D-CF on the repair of spinal cord injury.Forty Sprague-Dawley rats were divided into four groups: sham (only laminectomy was performed),spinal cord injury (transection injury of T10 spinal cord without any transplantation),3D-CF (3D scaffold was transplanted into the local injured cavity),and 3D-CF + NSCs (3D scaffold co-cultured with NSCs was transplanted into the local injured cavity.Neuroelectrophysiology,imaging,hematoxylin-eosin staining,argentaffin staining,immunofluorescence staining,and western blot assay were performed.Apart from the sham group,neurological scores were significantly higher in the 3D-CF + NSCs group compared with other groups.Moreover,latency of the 3D-CF + NSCs group was significantly reduced,while the amplitude was significantly increased in motor evoked potential tests.The results of magnetic resonance imaging and diffusion tensor imaging showed that both spinal cord continuity and the filling of injury cavity were the best in the 3D-CF + NSCs group.Moreover,regenerative axons were abundant and glial scarring was reduced in the 3D-CF + NSCs group compared with other groups.These results confirm that implantation of 3D-CF combined with NSCs can promote the repair of injured spinal cord.This study was approved by the Institutional Animal Care and Use Committee of People’s Armed Police Force Medical Center in 2017 (approval No.2017-0007.2).
文摘Collagen protein is an ideal scaffold material for the transplantation of neural stem cells. In this study rat neural stern cells were seeded into a three-dimensional collagen gel scaffold, with suspension cultured neural stem cells being used as a control group. Neural stem cells, which were cultured in medium containing epidermal growth factor and basic fibroblast growth factor, actively expanded and formed neurospheres in both culture groups. In serum-free medium conditions, the processes extended from neurospheres in the collagen gel group were much longer than those in the suspension culture group. Immunofluorescence staining showed that neurespheres cultured in collagen gels were stained positive for nestin and differentiated cells were stained positive for the neuronal marker βIII-tubulin, the astrocytic marker glial fibrillary acidic protein and the oligodendrocytic marker 2＇,3＇-cyclic nucleotide 3＇-phosphodiesterase. Compared with neurospheres cultured in suspension, the differentiation potential of neural stem cells cultured in collagen gels increased, with the formation of neurons at an early stage. Our results show that the three-dimensional collagen gel culture system is superior to suspension culture in the proliferation, differentiation and process outgrowth of neural stem cells.
基金supported by the National Science Fund for Distinguished Young Scholars(42225107)the National Natural Science Foundation of China(42001326,42371414,42171409,and 42271419)+1 种基金the Natural Science Foundation of Guangdong Province of China(2022A1515012207)the Basic and Applied Basic Research Project of Guangzhou Science and Technology Planning(202201011539)。
文摘Three-dimensional(3D)urban structures play a critical role in informing climate mitigation strategies aimed at the built environment and facilitating sustainable urban development.Regrettably,there exists a significant gap in detailed and consistent data on 3D building space structures with global coverage due to the challenges inherent in the data collection and model calibration processes.In this study,we constructed a global urban structure(GUS-3D)dataset,including building volume,height,and footprint information,at a 500 m spatial resolution using extensive satellite observation products and numerous reference building samples.Our analysis indicated that the total volume of buildings worldwide in2015 exceeded 1×10^(12)m^(3).Over the 1985 to 2015 period,we observed a slight increase in the magnitude of 3D building volume growth(i.e.,it increased from 166.02 km3 during the 1985–2000 period to 175.08km3 during the 2000–2015 period),while the expansion magnitudes of the two-dimensional(2D)building footprint(22.51×10^(3) vs 13.29×10^(3)km^(2))and urban extent(157×10^(3) vs 133.8×10^(3)km^(2))notably decreased.This trend highlights the significant increase in intensive vertical utilization of urban land.Furthermore,we identified significant heterogeneity in building space provision and inequality across cities worldwide.This inequality is particularly pronounced in many populous Asian cities,which has been overlooked in previous studies on economic inequality.The GUS-3D dataset shows great potential to deepen our understanding of the urban environment and creates new horizons for numerous 3D urban studies.
文摘To address the problem of multi-missile cooperative interception against maneuvering targets at a prespecified impact time and desired Line-of-Sight(LOS)angles in ThreeDimensional(3D)space,this paper proposes a 3D leader-following cooperative interception guidance law.First,in the LOS direction of the leader,an impact time-controlled guidance law is derived based on the fixed-time stability theory,which enables the leader to complete the interception task at a prespecified impact time.Next,in the LOS direction of the followers,by introducing a time consensus tracking error function,a fixed-time consensus tracking guidance law is investigated to guarantee the consensus tracking convergence of the time-to-go.Then,in the direction normal to the LOS,by combining the designed global integral sliding mode surface and the second-order Sliding Mode Control(SMC)theory,an innovative 3D LOS-angle-constrained interception guidance law is developed,which eliminates the reaching phase in the traditional sliding mode guidance laws and effectively saves energy consumption.Moreover,it effectively suppresses the chattering phenomenon while avoiding the singularity issue,and compensates for unknown interference caused by target maneuvering online,making it convenient for practical engineering applications.Finally,theoretical proof analysis and multiple sets of numerical simulation results verify the effectiveness,superiority,and robustness of the investigated guidance law.
文摘Objective:Squamous cell carcinoma(SCC)represents the most common histotype of all head and neck malignancies and includes oropharyngeal squamous cell carcinoma(OSCC),a tumor associated with different clinical outcomes and linked to human papilloma virus(HPV)status.Translational research has few available in vitro models with which to study the different pathophysiological behavior of OSCCs.The present study proposes a 3-dimensional(3 D)biomimetic collagen-based scaffold to mimic the tumor microenvironment and the crosstalk between the extracellular matrix(ECM)and cancer cells.Methods:We compared the phenotypic and genetic features of HPV-positive and HPV-negative OSCC cell lines cultured on common monolayer supports and on scaffolds.We also explored cancer cell adaptation to the 3 D microenvironment and its impact on the efficacy of drugs tested on cell lines and primary cultures.Results:HPV-positive and HPV-negative cell lines were successfully grown in the 3 D model and displayed different collagen fiber organization.The 3 D cultures induced an increased expression of markers related to epithelial–mesenchymal transition(EMT)and to matrix interactions and showed different migration behavior,as confirmed by zebrafish embryo xenografts.The expression of hypoxia-inducible factor 1α(1α)and glycolysis markers were indicative of the development of a hypoxic microenvironment inside the scaffold area.Furthermore,the 3 D cultures activated drug-resistance signaling pathways in both cell lines and primary cultures.Conclusions:Our results suggest that collagen-based scaffolds could be a suitable model for the reproduction of the pathophysiological features of OSCCs.Moreover,3 D architecture appears capable of inducing drug-resistance processes that can be studied to better our understanding of the different clinical outcomes of HPV-positive and HPV-negative patients with OSCCs.
基金supported by the Korea Health Technology R&D Project through the Korea Health Industry Development Institute(KHIDI),the Ministry of Health&Welfare,Republic of Korea(Grant Number:HI14C2143)the National Research Foundation of Korea(NRF)grant funded by the Korea government(MIST)(NRF-2021R1A2C2009665)。
文摘Osteoconductive function is remarkably low in bone disease in the absence of bone tissue surrounding the grafting site,or if the bone tissue is in poor condition.Thus,an effective bone graft in terms of both osteoconductivity and osteoinductivity is required for clinical therapy.Recently,the three-dimensional(3D)kagome structure has been shown to be advantageous for bone tissue regeneration due to its mechanical properties.In this study,a polycaprolactone(PCL)kagome-structure scaffold containing a hyaluronic acid(HA)-based hydrogel was fabricated using a 3D printing technique.The retention capacity of the hydrogel in the scaffold was assessed in vivo with a rat calvaria subcutaneous model for 3 weeks,and the results were compared with those obtained with conventional 3D-printed PCL grid-structure scaffolds containing HA-based hydrogel and bulk-type HA-based hydrogel.The retained hydrogel in the kagome-structure scaffold was further evaluated by in vivo imaging system analysis.To further reinforce the osteoinductivity of the kagome-structure scaffold,a PCL kagome-structure scaffold with bone morphogenetic protein-2(BMP-2)containing HA hydrogel was fabricated and implanted in a calvarial defect model of rabbits for 16 weeks.The bone regeneration characteristics were evaluated with hematoxylin and eosin(H&E),Masson’s trichrome staining,and micro-CT image analysis.
文摘In this work, patterned macropores with a diameter larger than 100 μm were introduced to pristine three-dimensional (3D) nanofibrous bacterial cellulose (BC) scaffolds by using the infrared laser micromachining technique in an attempt to create an in vitro model for the culture of breast cancer cells. The morphology, pore structure, and mechanical performance of the obtained patterned macroporous BC (PM-BC) scaffolds were characterized by scanning electron microscopy (SEM), mercury intrusion porosimeter, and mechanical testing. A human breast cancer cell (MDA-MB-231) line was cultured onto the PM-BC scaffolds to investigate the role of macropores in the control of cancer cell behavior. MTT assay, SEM, and hematoxylin and eosin (H&E) staining were employed to determine cell adhesion, growth, proliferation, and infiltration. The PM-BC scaffolds were found to be able to promote cellular adhesion and proliferation on the scaffolds, and further to allow for cell infiltration into the PM-BC scaffolds. The results demonstrated that BC scaffolds with laser-patterned macropores were promising for the in vitro 3D culture of breast cancer cells.
文摘BACKGROUND Cardiovascular diseases are the major cause of mortality worldwide.Regeneration of the damaged myocardium remains a challenge due to mechanical constraints and limited healing ability of the adult heart tissue.Cardiac tissue engineering using biomaterial scaffolds combined with stem cells and bioactive molecules could be a highly promising approach for cardiac repair.Use of biomaterials can provide suitable microenvironment to the cells and can solve cell engraftment problems associated with cell transplantation alone.Mesenchymal stem cells(MSCs)are potential candidates in cardiac tissue engineering because of their multilineage differentiation potential and ease of isolation.Use of DNA methyl transferase inhibitor,such as zebularine,in combination with three-dimensional(3D)scaffold can promote efficient MSC differentiation into cardiac lineage,as epigenetic modifications play a fundamental role in determining cell fate and lineage specific gene expression.AIM To investigate the role of collagen scaffold and zebularine in the differentiation of rat bone marrow(BM)-MSCs and their subsequent in vivo effects.METHODS MSCs were isolated from rat BM and characterized morphologically,immunophenotypically and by multilineage differentiation potential.MSCs were seeded in collagen scaffold and treated with 3μmol/L zebularine in three different ways.Cytotoxicity analysis was done and cardiac differentiation was analyzed at the gene and protein levels.Treated and untreated MSC-seeded scaffolds were transplanted in the rat myocardial infarction(MI)model and cardiac function was assessed by echocardiography.Cell tracking was performed by DiI dye labeling,while regeneration and neovascularization were evaluated by histological and immunohistochemical analysis,respectively.RESULTS MSCs were successfully isolated and seeded in collagen scaffold.Cytotoxicity analysis revealed that zebularine was not cytotoxic in any of the treatment groups.Cardiac differentiation analysis showed more pronounced results in the type 3 treatment group which was subsequently chosen for the transplantation in the in vivo MI model.Significant improvement in cardiac function was observed in the zebularine treated MSC-seeded scaffold group as compared to the MI control.Histological analysis also showed reduction in fibrotic scar,improvement in left ventricular wall thickness and preservation of ventricular remodeling in the zebularine treated MSC-seeded scaffold group.Immunohistochemical analysis revealed significant expression of cardiac proteins in DiI labeled transplanted cells and a significant increase in the number of blood vessels in the zebularine treated MSC-seeded collagen scaffold transplanted group.CONCLUSION Combination of 3D collagen scaffold and zebularine treatment enhances cardiac differentiation potential of MSCs,improves cell engraftment at the infarcted region,reduces infarct size and improves cardiac function.
文摘Liposarcoma is one of the most common soft tissue sarcomas,however,its occurrence rate is still rare compared to other cancers.Due to its rarity,in vitro experiments are an essential approach to elucidate liposarcoma pathobiology.Conventional cell culture-based research(2D cell culture)is still playing a pivotal role,while several shortcomings have been recently under discussion.In vivo,mouse models are usually adopted for pre-clinical analyses with expectations to overcome the issues of 2D cell culture.However,they do not fully recapitulate human dedifferentiated liposarcoma(DDLPS)characteristics.Therefore,three-dimensional(3D)culture systems have been the recent research focus in the cell biology field with the expectation to overcome at the same time the disadvantages of 2D cell culture and in vivo animal models and fill in the gap between them.Given the liposarcoma rarity,we believe that 3D cell culture techniques,including 3D cell cultures/co-cultures,and Patient-Derived tumor Organoids(PDOs),represent a promising approach to facilitate liposarcoma investigation and elucidate its molecular mechanisms and effective therapy development.In this review,we first provide a general overview of 3D cell cultures compared to 2D cell cultures.We then focus on one of the recent 3D cell culture applications,Patient-Derived Organoids(PDOs),summarizing and discussing several PDO methodologies.Finally,we discuss the current and future applications of PDOs to sarcoma,particularly in the field of liposarcoma.
