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AbstractIron oxide (Fe-O) has anti-tumor properties, due to its ability of catalyzing hydrogen peroxide (H2O2) of tumor cells to generate reactive oxygen species (ROS) and then cause ferroptosis. Its anti-tumor performance is restricted due to insufficient H2O2 in tumor cells. A nanomedicine, Au nanoparticles (NPs) grown on Fe-O, was integrated into poly-l-lactide (PLLA) scaffolds. Results indicated that Au NPs could consume glucose of tumor cells to produce H2O2, which supplemented reaction substrate. PLLA/Au@Fe-O scaffold showed enhanced anti-tumor activities against MG63, including increased mortality, decreased migration and colony formation. PLLA/Au@Fe-O scaffold promoted ferroptosis in MG63, including up-regulation of COX-2 protein, down-regulation of FTH1 protein and GPX4 protein. PLLA/Au@Fe-O scaffold also promoted autophagy in MG63, including down-regulation of P62 protein, and up-regulation of LC3BII/I. Mechanistically, PLLA/Au@Fe-O scaffold possessed enhanced anti-tumor activities through promoting ferroptosis and autophagy. [ABSTRACT FROM AUTHOR]

Background: One-step cell-based techniques of cartilage repair that lead to restoration of durable chondral tissue and long-term maintenance of joint function are cost-effective and ideal for routine use. Purposes: To examine the long-term clinical outcomes, after a mean follow-up duration of 14 years, of cartilage repair in the knee using a hyaluronic acid–based scaffold in association with bone marrow aspirate concentrate (HA-BMAC) and to evaluate the effect of age, lesion characteristics, and associated treatments on the outcome of this cartilage repair method. Study Design: Case series; Level of evidence, 4. Methods: Patients were followed prospectively for a mean duration of 14.0 years after undergoing treatment of knee full-thickness articular cartilage injury using HA-BMAC. Clinical evaluation consisted of the patient-reported scoring tools of the visual analog scale and the Knee injury and Osteoarthritis Outcome Score, which were completed preoperatively and at the time of final follow-up. Results: A total of 26 patients with a mean age of 48.3 years (17 male, 9 female) and median chondral lesion size of 6.6 cm2 (range, 1-27 cm2) were followed prospectively. There were 3 treatment failures, and 1 patient who underwent medial compartment unicompartmental arthroplasty 12 years after HA-BMAC treatment of patellar chondral injury. Of the 22 remaining patients, after a mean final follow-up duration of 14.0 years (range, 12-16 years), the median visual analog scale score of 0.6 was significantly decreased from the preoperative median score of 5.0 (P <.001). The median Knee injury and Osteoarthritis Outcome Score Pain (92), Symptoms (86), Activities of Daily Living (96), Sports (85), and Quality of Life (88) subscale values were all increased compared with the preoperative scores (P ≤.001). There was no correlation of clinical outcome score and body mass index. Conclusion: One-step cartilage repair of full-thickness chondral defects in the knee using an HA-BMAC led to successful long-term clinical outcomes and maintenance of joint junction after a mean follow-up duration of 14 years. Long-term clinical success in active, nonobese patients has been uniformly demonstrated across a wide range of patient ages and lesion types, including cases of multicompartment involvement, treatment of associated conditions, and large or bipolar chondral lesions. [ABSTRACT FROM AUTHOR]

The dura mater protects underlying tissues and cerebrospinal fluid, but dural abnormalities can cause leaking and meningitis and wound infections. This review emphasizes the relevance of dural repair and the progress of dural reconstruction materials, focusing on biological scaffolds. A comprehensive assessment of dural substitution literature focused on composite, acellular, natural, synthetic, and homologous materials. Decellularized dura scaffolds as viable natural biomaterials for tissue engineering are explored in this overview of these materials' properties, effectiveness, and therapeutic uses. The evaluation also compares materials and assesses host tissue response in preclinical and clinical studies. The review highlights various dural substitution findings. There is no gold standard for dural repair, despite the variety of materials used. Replicating natural dura mater's mechanical and structural qualities is difficult. Recent research suggests that decellularized dura scaffolds can regenerate tissue while reducing inflammation and transplant rejection. Furthermore, the movement toward personalized medicine in this sector suggests that bespoke alternatives might be chosen depending on patient characteristics, improving treatment effects. Synthesizing dural replacement research and clinical uses in this review adds to knowledge. It tackles standard materials' shortcomings and shows how biological scaffolds might improve dural repair. The analysis opens the door to personalized dural repair research that might enhance patient outcomes and advance neurosurgery. The insights presented herein highlight the intriguing prospects for appropriate dural restorative materials, seeking to improve dural defect treatment. [ABSTRACT FROM AUTHOR]

This systematic review aims to document the available research evidence regarding using mesenchymal stem cells (MSCs) and acellular amniotic membranes (AAM) as scaffolds in the murine model for tissue regeneration. This research was developed by analyzing available information on databases like Google Scholar, Pubmed, Scopus, and Web of Science, using the following key terms "Human Stem Cells", "Amniotic membrane", "Wound healing' ' and "Animal model". A total of 519 articles published from January 2013 to March 2024 were found, but only 8 studies were included in this review, the inclusion criteria were as follows the use of human-derived stem cells (UCMSCs and ADMSCs) seeded in decellularized hAM, in murine models with induced wounds (incisions or burns); exclusion criteria: stem cells obtained from non-human origin, combination of human stem cells from different tissues, use of a different biological scaffold, and studies that not assess efficacy in skin regeneration. The main outcomes were decreased wound closure time, increased angiogenesis, remodeling and increase in extracellular matrix deposition, increased synthesis of growth factors and anti-inflammatory cytokines, and optimization of biomechanical properties. Moreover, one of the main findings was that combining these methods can improve the healing process in chronic wounds. The main bias was related to the inclusion of more studies that used ADMSC (5 of 8); additionally, there were differences in the animal model used, the induced wound, and the comparison of different variables between the studies. In conclusion, we found that the combination of MSCs and AAM as a bio-scaffold improves general tissue healing and regeneration. [ABSTRACT FROM AUTHOR]

Cardiovascular diseases represent one of the leading causes of death worldwide. Despite significant advances in the diagnosis and treatment of these diseases, numerous challenges remain in managing them. One of these challenges is the need for replacements for damaged cardiac tissues that can restore the normal function of the heart. Amniotic membrane, as a biological scaffold with unique properties, has attracted the attention of many researchers in recent years. This membrane, extracted from the human placenta, contains growth factors, cytokines, and other biomolecules that play a crucial role in tissue repair. Its anti-inflammatory, antibacterial, and wound-healing properties have made amniotic membrane a promising option for the treatment of heart diseases. This review article examines the applications of amniotic membrane in cardiovascular diseases. By focusing on the mechanisms of action of this biological scaffold and the results of clinical studies, an attempt will be made to evaluate the potential of using amniotic membrane in the treatment of heart diseases. Additionally, the existing challenges and future prospects in this field will be discussed.

BACKGROUND: Nanocomposite hydrogel has great research prospects and application potential in the treatment of osteoarthritis. OBJECTIVE: To review the research progress of nanocomposite hydrogel in osteoarthritis and cartilage repair. METHODS: Databases such as CNKI and PubMed were searched. The English key words were “nanocomposite hydrogel, nanogel, osteoarthritis, cartage, physical encapsulation, electrostatic interaction, covalent crosslinking”, and the Chinese key words were “nanocomposite hydrogel, nanogel, osteoarthritis, cartage, physical encapsulation, physical encapsulation, electrostatic effect, covalent cross-linking”. After an initial screening of all articles based on inclusion and exclusion criteria, 71 articles with high correlation were retained for review. RESULTS AND CONCLUSION: In cell or animal experiments, nanocomposite hydrogel has the effect of improving osteoarthritis. Nanocomposite hydrogel can promote cartilage repair, improve the internal environment of osteoarthritis, and achieve the therapeutic purpose of osteoarthritis by improving the mechanical environment between joints, carrying targeted drugs, and promoting the chondrogenesis of seed cells. At present, the research of nanocomposite hydrogel in osteoarthritis disease still has a huge space to play. It is expected to open up a new way for the clinical treatment of osteoarthritis by continuing to deepen the research of material preparation and actively carrying out cell and animal experiments. [ABSTRACT FROM AUTHOR]

Three-dimensionally printed vascularized tissue, which is suitable for treating human cardiovascular diseases, should possess excellent biocompatibility, mechanical performance, and the structure of complex vascular networks. In this paper, we propose a method for fabricating vascularized tissue based on coaxial 3D bioprinting technology combined with the mold method. Sodium alginate (SA) solution was chosen as the bioink material, while the cross-linking agent was a calcium chloride (CaCl2) solution. To obtain the optimal parameters for the fabrication of vascular scaffolds, we first formulated theoretical models of a coaxial jet and a vascular network. Subsequently, we conducted a simulation analysis to obtain preliminary process parameters. Based on the aforementioned research, experiments of vascular scaffold fabrication based on the coaxial jet model and experiments of vascular network fabrication were carried out. Finally, we optimized various parameters, such as the flow rate of internal and external solutions, bioink concentration, and cross-linking agent concentration. The performance tests showed that the fabricated vascular scaffolds had levels of satisfactory degradability, water absorption, and mechanical properties that meet the requirements for practical applications. Cellular experiments with stained samples demonstrated satisfactory proliferation of human umbilical vein endothelial cells (HUVECs) within the vascular scaffold over a seven-day period, observed under a fluorescent inverted microscope. The cells showed good biocompatibility with the vascular scaffold. The above results indicate that the fabricated vascular structure initially meet the requirements of vascular scaffolds. [ABSTRACT FROM AUTHOR]

BACKGROUND: Osteonecrosis of the femoral head is a common orthopedic disease, and hip preservation surgery with bone grafting is commonly used in the early stage, in which autologous bone and allograft bone are commonly used as bone grafting materials. However, autologous bone transplantation is highly traumatic and bone supply is limited, and allograft bone is rich in sources, but there are serious risks of immune rejection and absorption. In recent years, the tissue engineering technique based on mesenchymal stem cells is a new method for the treatment of femoral head necrosis, which is gradually widely used after basic experiments and clinical application. OBJECTIVE: To review the application and prospect of tissue engineering in the treatment of osteonecrosis of the femoral head to provide a new choice for the clinical treatment of osteonecrosis of the femoral head. METHODS: The PubMed database and CNKI database from 2013 to 2023 were searched by the first author with Chinese and English search terms “tissue engineering, mesenchymal stem cells, biological scaffolds, cytokines, osteonecrosis of the femoral head, bone graft, hip preservation”. The articles on the treatment of osteonecrosis of the femoral head with tissue engineering technology were selected, and 55 representative articles were included for review after the initial screening of all articles according to the inclusion and exclusion criteria. RESULTS AND CONCLUSION: (1) With the continuous development of biotechnology and materials science, great progress has been made in the treatment of osteonecrosis of the femoral head by bone tissue engineering, such as the application of gene-modified mesenchymal stem cells to repair osteonecrosis, the combination of gene recombination technology and surface modification technology with bone tissue engineering in the treatment of osteonecrosis of the femoral head. (2) When applied to the necrotic femoral head, tissue engineering technology can promote the regeneration of necrotic bone tissue and the repair of the vascular system, provide biomechanical stability for the necrotic area, and use bioactive factors to accelerate the repair of seed cells to complete the regeneration of new bone in necrotic area. (3) However, most of these studies are still in the animal experiment stage, and there are still many unsolved problems and challenges in bone tissue engineering research. With the rapid development of nanotechnology, tissue engineering and clinical medicine, biomimetic replacement bone grafting materials with perfect performance are expected to come into being. (4) In the future, bone tissue engineering for osteonecrosis of the femoral head is expected to be a satisfactory treatment for patients with hip preservation. [ABSTRACT FROM AUTHOR]

Hydrogels are hydrophilic three‐dimensional networks containing a large amount of water, with physicochemical properties similar to extracellular matrix and controlled mechanical strength, making them ideal scaffolds for 3D cell culture and tissue engineering. However, the cross‐linked hydrogel network often restricts the migration of cells and the exchange of nutrients, which affects cell proliferation and the development of normal tissues. In recent years, hydrogels with pore‐channel structures have attracted significant attention, but these spatial structures are usually preconstructed before gelation, posing challenges in meeting the dynamic physiological conditions required during cell and tissue growth. Therefore, considerable efforts have been devoted to structurally regulate the scaffolds after gelation, so as to enhance the interactions between the scaffolds and cells for promoting the growth of cells and tissues. This review firstly outlines the preparation of hydrogel scaffolds with pore structure and the necessity of postgelation pore modulation. Two types of methods for postgelation pore modulation, including chemical degradation and physical dissolution, are then summarized. Finally, the potential application of such postgelation structural modulation in 3D cell culture and tissue engineering is discussed. [ABSTRACT FROM AUTHOR]

Advancements in regenerative medicine have highlighted the potential of decellularized extracellular matrix (ECM) as a scaffold for organ bioengineering. Although the potential of ECM in major organ systems is well-recognized, studies focusing on the angiogenic effects of pancreatic ECM are limited. This study investigates the capabilities of pancreatic ECM, particularly its role in promoting angiogenesis. Using a Triton-X-100 solution, porcine pancreas was successfully decellularized, resulting in a significant reduction in DNA content (97.1% removal) while preserving key pancreatic ECM components. A three-dimensional ECM hydrogel was then created from this decellularized tissue and used for cell culture. Biocompatibility tests demonstrated enhanced adhesion and proliferation of mouse embryonic stem cell-derived endothelial cells (mES-ECs) and human umbilical vein endothelial cells (HUVECs) in this hydrogel compared to conventional scaffolds. The angiogenic potential was evaluated through tube formation assays, wherein the cells showed superior tube formation capabilities in ECM hydrogel compared to rat tail collagen. The RT-PCR analysis further confirmed the upregulation of pro-angiogenic genes in HUVECs cultured within the ECM hydrogel. Specifically, HUVECs cultured in the ECM hydrogel exhibited a significant upregulation in the expression of MMP2, VEGF and PAR-1, compared to those cultured in collagen hydrogel or in a monolayer condition. The identification of ECM proteins, specifically PRSS2 and Decorin, further supports the efficacy of pancreatic ECM hydrogel as an angiogenic scaffold. These findings highlight the therapeutic promise of pancreatic ECM hydrogel as a candidate for vascularized tissue engineering application. [ABSTRACT FROM AUTHOR]

BACKGROUND: In recent years, with the development of biological scaffold materials and bioprinting technology, tissue-engineered bone has become a research hotspot in bone defect repair. OBJECTIVE: To summarize the current treatment methods for bone defects, summarize the biomaterials and bioprinting technology for preparing tissueengineered bone scaffolds, and explore the application of biomaterials and printing technology in tissue engineering and the current challenges. METHODS: Search terms were “bone defect, tissue engineering, biomaterials, 3D printing technology, 4D printing technology, bioprinting, biological scaffold, bone repair” in Chinese and English. Relevant documents published from January 1, 2009 to December 1, 2022 were retrieved on CNKI, PubMed and Web of Science databases. After being screened by the first author, high-quality references were added. A total of 93 articles were included for review. RESULTS AND CONCLUSION: The main treatment methods for bone defects include bone transplantation, membrane-guided regeneration, gene therapy, bone tissue engineering, etc. The best treatment method is still uncertain. Bone tissue engineering technology is a new technology for the treatment of bone defects. It has become the focus of current research by constructing three-dimensional structures that can promote the proliferation and differentiation of osteoblasts and enhance the ability of bone formation. Biological scaffold materials are diverse, with their characteristics, advantages and disadvantages. A single biological material cannot meet the demand for tissue-engineered bone for the scaffold. Usually, multiple materials are combined to complement each other, which is to meet the demand for mechanical properties while taking into account the biological properties of the scaffold. Bioprinting technology can adjust the pore of the scaffold, build a complex spatial structure, and is more conducive to cell adhesion, proliferation and differentiation. The emerging 4D printing technology introduces “time” as the fourth dimension to make the prepared scaffold dynamic. With the synchronous development of smart materials, 4D printing technology provides the possibility of efficient repair of bone defects in the future. [ABSTRACT FROM AUTHOR]

BACKGROUND: Most rotator cuff injuries occur in the supraspinatus tendon. Clinical treatment of rotator cuff injuries is very limited due to the lack of blood vessels and the complex anatomical structure of the rotator cuff. The rapid development of tissue engineering technology and stem cell biology has brought new hope for improving the quality of tendon repair. OBJECTIVE: To prepare human umbilical cord mesenchymal stem cells/gelatin methacrylate composite scaffolds by bio-3D printing technology to observe the effect of this scaffold on repairing rotator cuff injury. METHODS: (1) In vitro cell assay: The gelatin microcarrier was prepared. The tissue engineered stem cells were constructed by inoculating human umbilical cord mesenchymal stem cells on the surface of gelatin microcarrier. Gelatin methacrylate hydrogel printing ink was prepared. Tissue engineered stem cells were re-suspended with gelatin methacrylate hydrogel printing ink and put into the bio-ink container of 3D printer for printing. Human umbilical cord mesenchymal stem cells/gelatin methacrylate composite scaffold was obtained after 5 minutes of blue light irradiation and curing. The activity of human umbilical cord mesenchymal stem cells in scaffolds was detected by dead/alive staining and CCK-8 assay. (2) In vivo animal experiments: A random block design method was used to randomly assign 24 SD rats to 4 groups with 6 rats in each group. No treatment was given in the normal group. The rotator cuff injury model of supratinatus tendon tear was established in the rotator cuff injury group, the simple scaffold group, and the cellular scaffold group. The gelatin methacrylate scaffold and human umbilical cord mesenchymal stem cell/gelatin methacrylatecomposite scaffold were implanted into the tendon injury after the model was made in the simple scaffold group and the cellular scaffold group, respectively. Four weeks after operation, behavioral tests and histopathological morphology observation of supraspinatus tendon of rotator cuff were performed. RESULTS AND CONCLUSION: (1) In vitro cellular assay: The dead/alive staining showed that gelatin microcarrier could reduce the damage of human umbilical cord mesenchymal stem cells caused by 3D printing process. With the extension of culture time, the survival rate of human umbilical cord mesenchymal stem cells increased in the scaffold. The results of CCK-8 assay showed that with the extension of culture time, the activity of human umbilical cord mesenchymal stem cells in the scaffold did not change significantly. (2) In vivo animal experiments: Behavioral test results showed that compared with rotator cuff injury group and simple scaffold group, cellular scaffold group significantly improved limb motor function. The results of hematoxylin-eosin and Masson staining of rotator cuff supraspinatus tendon showed that compared with rotator cuff injury group and simple scaffold group, the muscle fiber arrangement in the cellular scaffold group was more regular; there was no obvious inflammatory cell infiltration, and the percentage of collagen volume decreased. The results of immunofluorescence staining showed that the expression levels of interleukin 6 and tumor necrosis factor α in the rotator cuff supraspinatus tendon were significantly decreased in the cellular scaffold group compared with the rotator cuff injury group and the simple scaffold group. (3) The results showed that bio3D-printed cell scaffolds encapsulating human umbilical cord mesenchymal stem cells/gelatin methacrylate could promote tissue repair and regeneration of rotator cuff injuries. [ABSTRACT FROM AUTHOR]

ABSTRACTInfection research largely relies on classical cell culture or mouse models. Despite having delivered invaluable insights into host-pathogen interactions, both have limitations in translating mechanistic principles to human pathologies. Alternatives can be derived from modern Tissue Engineering approaches, allowing the reconstruction of functional tissue models in vitro. Here, we combined a biological extracellular matrix with primary tissue-derived enteroids to establish an in vitro model of the human small intestinal epithelium exhibiting in vivo-like characteristics. Using the foodborne pathogen Salmonella enterica serovar Typhimurium, we demonstrated the applicability of our model to enteric infection research in the human context. Infection assays coupled to spatio-temporal readouts recapitulated the established key steps of epithelial infection by this pathogen in our model. Besides, we detected the upregulation of olfactomedin 4 in infected cells, a hitherto unrecognized aspect of the host response to Salmonella infection. Together, this primary human small intestinal tissue model fills the gap between simplistic cell culture and animal models of infection, and shall prove valuable in uncovering human-specific features of host-pathogen interplay.

Human acellular amniotic membrane (HAAM) has emerged as a promising tool in the field of regenerative medicine, particularly for wound healing and tissue regeneration. HAAM provides a natural biological scaffold with low immunogenicity and good anti-infective and anti-scarring results. Despite its potential, the clinic application of HAAM faces challenges, particularly with respect to the preparation methods and its low mechanical strength. This review provides a comprehensive overview of HAAM, covering its preparation, sterilization, preclinical research, and clinical applications. This review also discusses promising decellularization and sterilization methods, such as Supercritical Carbon Dioxide (SC-CO2), and the need for further research into the regenerative mechanisms of HAAM. In addition, we discuss the potential of HAAM as a skin dressing and cell delivery system in preclinical research and clinical applications. Both the safety and effectiveness of HAAM have been validated by extensive research, which provides a robust foundation for its clinical application. [ABSTRACT FROM AUTHOR]

Purpose: To describe a new surgical technique for osteochondral lesions of the ankle, using bone marrow concentrate on a scaffold and homologous bone graft positioned through a retrograde approach. Many surgical options for ankle osteochondral lesions have been described, and the ideal treatment is still debated. Bone marrow stimulating techniques are recommended for cystic lesions, with some concerns regarding the healing potential of the subchondral bone. In case of wide osteochondral defects, regenerative solutions are preferred but a massive chondral debridement is usually required. To overcome these problems, a novel technique is proposed. Methods: The proposed technique was performed on patients affected by osteochondral lesions of the talus, either cysts with intact cartilage or wide osteochondral defects. A preoperative magnetic resonance imaging was obtained to localize the lesion. A 6-mm tarsal tunnel was retrogradely created toward the lesion, to allow a complete sub-endo-chondral debridement preserving the healthy cartilage. A hyaluronan scaffold soaked with a previously prepared bone marrow concentrate was retrogradely positioned under the cartilage surface and the tunnel was filled with homologous bone graft. Preoperative clinical scores and postoperative x-rays were registered. Results: Four patients were treated using this technique. No intraoperative and postoperative complications occurred. Good bone remodeling was observed at 12-week postoperative x-rays. Conclusions: This technique combines the mini-invasiveness of retrograde drilling with the regenerative properties of biological scaffold soaked with bone marrow concentrate. Despite further research being needed, it seems a new viable solution to treat both subchondral cysts and large osteochondral defects of the ankle, whose management is still controversial. [ABSTRACT FROM AUTHOR]

Carbon foam (CF), a lightweight, open-pore, and 3 D interconnected network-like structure comprising turbostratic carbon, is mainly synthesized from polymer precursors like polyurethane and melamine foams, mesophase pitch, coal tar pitch, etc. The glassy variant of CF known as reticulated vitreous carbon (RVC) foam finds use as electrodes in electrochemical cells and Li-ion batteries, field emission cathode, high-temperature insulation, and electromagnetic interference shielding materials. However, of late, its implication has been extended to biomaterial platforms and tissue engineering avenues due to its high porosity and biocompatibility. RVC foam with tunable porosity, density, and mechanical properties can be synthesized by judiciously selecting the precursor materials and their processing conditions. Although proven to be bioinert, its surface modification renders it bioactive and hydrophilic to support cell adhesion and growth. Several groups including ours have demonstrated its implication in supporting osteogenic differentiation of mesenchymal stem cells (MSCs). In this regard, the present review attempts to provide some critical insights into the fabrication, structure, and characteristics of RVC foam and also highlights the challenges and future prospects of this material concerning its plausible implications in bone tissue engineering. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To summarize research progress on forming dental pulp-like tissue from dental pulp stem cells via a co-culture system, as well as provide ideas for stem cell therapy for dental pulp tissue regeneration. METHODS: The first author searched PubMed, CNKI, and Wanfang databases for relevant literature published before May 2022. The English search terms were “dental pulp regeneration, dental pulp stem cell, co-culture, tissue engineering, signaling pathway”, and the Chinese search terms were “dental pulp regeneration, dental pulp stem cells, co-culture, tissue engineering, scaffold, signaling pathway”. Totally 67 articles meeting the criteria were summarized and described. RESULTS AND CONCLUSION: (1) Different combinations of cells are used in co-culture systems to form the main body of the cell and the combined body. (2) Direct co-culture and indirect co-culture are the two types of combination modes at present. Through the intervention of biological scaffold materials and a change in culture conditions, the co-culture outcome can be divided into two-dimensional regenerated tissues and three-dimensional regenerated tissues. (3) Direct co-culture creates an extracellular matrix and microenvironment that facilitates stem cell proliferation and differentiation through intercellular contact. (4) Indirect co-culture addresses the problem of insufficient sources of combined cells and immune rejection between individuals. The biological factors produced by the combined cells can be more easily made into clinical drugs and biological scaffold materials. (5) Though the co-culture system has superior performance in angiogenesis, there are few reports on other structures, and the regeneration of tissue from the co-culture outcome is uncertain. Furthermore, there are limitations to applying newly generated tissue generated by the co-culture system to clinical practice due to tooth anatomical constraints and rejection mechanisms. [ABSTRACT FROM AUTHOR]

Three-dimensionally printed vascularized tissue, which is suitable for treating human cardiovascular diseases, should possess excellent biocompatibility, mechanical performance, and the structure of complex vascular networks. In this paper, we propose a method for fabricating vascularized tissue based on coaxial 3D bioprinting technology combined with the mold method. Sodium alginate (SA) solution was chosen as the bioink material, while the cross-linking agent was a calcium chloride (CaCl2) solution. To obtain the optimal parameters for the fabrication of vascular scaffolds, we first formulated theoretical models of a coaxial jet and a vascular network. Subsequently, we conducted a simulation analysis to obtain preliminary process parameters. Based on the aforementioned research, experiments of vascular scaffold fabrication based on the coaxial jet model and experiments of vascular network fabrication were carried out. Finally, we optimized various parameters, such as the flow rate of internal and external solutions, bioink concentration, and cross-linking agent concentration. The performance tests showed that the fabricated vascular scaffolds had levels of satisfactory degradability, water absorption, and mechanical properties that meet the requirements for practical applications. Cellular experiments with stained samples demonstrated satisfactory proliferation of human umbilical vein endothelial cells (HUVECs) within the vascular scaffold over a seven-day period, observed under a fluorescent inverted microscope. The cells showed good biocompatibility with the vascular scaffold. The above results indicate that the fabricated vascular structure initially meet the requirements of vascular scaffolds.

Bilateral breast augmentation has been the top surgical procedure performed worldwide by plastic surgeons for the past 5 years. Complex breast revision patients are challenging, with the cleavage area being one of the most difficult areas to navigate. We present a novel technique for using biological scaffolds in revision breast augmentation surgery. A step-by-step surgical technique is presented, combined with a series of 11 cases where either SurgiMend® acellular dermal matrix (ADM) or GalaFLEX mesh was used specifically in the medial cleavage area to correct a difficult to manage soft tissue contour deformity. Eleven patients underwent revision breast augmentation with the use of the biological scaffolds in the medial cleavage area. The mean age was 43 years with a range of 29–68 years. All replacement breast implants were anatomical-shaped, medium profile, polyurethane-coated implants. GalaFLEX® mesh was used in six patients; five patients received SurgiMend® ADM. Mastopexy was performed in 8/11 patients. There were two complications in the same patient in this series, one emergency return to theater for bleeding and one minor scar revision. Revision breast augmentation surgery includes a smorgasbord of options that can be used individually or in combination, such as full or partial capsulectomy, removal alone or replacement of the implant, change to the tissue plane of where the implant sits, mastopexy, and fat transfer. In addition to these recognized treatments, we would like to advocate the option of a biological scaffold for extra support of the cleavage area in complex revision cases. [ABSTRACT FROM AUTHOR]

An ideal artificial bone implant should have similar mechanical properties and biocompatibility to natural bone, as well as an internal structure that facilitates stomatal penetration. In this work, 3D printing was used to fabricate and investigate artificial bone composites based on HA-ZrO2-PVA. The composites were proportionally configured using zirconia (ZrO2), hydroxyapatite (HA) and polyvinyl alcohol (PVA), where the ZrO2 played a toughening role and PVA solution served as a binder. In order to obtain the optimal 3D printing process parameters for the composites, a theoretical model of the extrusion process of the composites was first established, followed by the optimization of various parameters including the spray head internal diameter, extrusion pressure, extrusion speed, and extrusion line width. The results showed that, at the optimum parameters of a spray head diameter of 0.2 mm, extrusion pressure values ranging from 1–3 bar, a line spacing of 0.8–1.5 mm, and a spray head displacement range of 8–10 mm/s, a better structure of biological bone scaffolds could be obtained. The mechanical tests performed on the scaffolds showed that the elastic modulus of the artificial bone scaffolds reached about 174 MPa, which fulfilled the biomechanical requirements of human bone. According to scanning electron microscope observation of the scaffold sample, the porosity of the scaffold sample was close to 65%, which can well promote the growth of chondrocytes and angiogenesis. In addition, c5.18 chondrocytes were used to verify the biocompatibility of the composite materials, and the cell proliferation was increased by 100% when compared with that of the control group. The results showed that the composite has good biocompatibility. [ABSTRACT FROM AUTHOR]

Copyright of Cotton Textile Technology is the property of Cotton Textile Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective: To analyze the application efficacy of employing high-density porous polyethylene （Su-por） in combination with temporoparietal fascial flaps via a minimally invasive scalp incision in auricular reconstruction. Methods: This study carried out a retrospective analysis of 50 patients （50 ears in total） who underwentprimary auricular reconstruction with a Su-por scaffold in our hospital from June 2022 to January 2024. All patients underwent primary auricular reconstruction using a minimally invasive scalp incision with high-density porous polyethylene （Su-por） and temporoparietal fascial flaps. The postoperative treatment effects and complications were statistically analyzed. Results: The reconstructed ears of all patients survived. After 6 months of follow-up, the scar hyperplasia of the scalp minimally invasive incision was not obvious in any patient, and no significant hair loss was observed. The reconstructed auricle of 48 patients had a realistic shape and strong three-dimensional sense. With the extension of follow-up time, the three-dimensional structure of the auricle became clearer, and patient satisfaction increased. Among the remaining two patients, one case of flap necrosis survived after skin grafting and dressing changes. One patient had scar hyperplasia at the incision of the reconstructed ear due to a scar-prone constitution, and the shape of the auricle was not ideal, but the scar hyperplasia at the scalp incision was not obvious. Conclusion: One-stage ear reconstruction with high-density porous polyethylene （Su-por） combined with superficial temporal fascia flap through a minimally invasive scalp incision can better show the fine structure of the reconstructed ear. The minimally invasive scalp incision can effectively reduce the occurrence of scar hyperplasia and postoperative alopecia at the scalp incision., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright© by the Editorial Department of Journal of Clinical Otorhinolaryngology Head and Neck Surgery.)

Copyright of Journal of Chinese Institute of Food Science & Technology / Zhongguo Shipin Xuebao is the property of Journal of Chinese Institute of Food Science & Technology Periodical Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Dental problems including cavities, periodontitis, apical periodontitis, and pulpitis are among the most cost-consuming burden for both patients and the health care system all over the world. The pathological consequences of these complications importantly lead to tooth loss causing functional and psychological conflictions for patients. The traditional treatment includes removing the impaired tooth or its restoration using hard restorative materials that are supposed to mimic the tissue of enamel or dentine whereas these materials cannot simulate the chemical, biological, or physical characteristics of a natural tooth. Therefore, different daily-progressing methods of tissue engineering (TE) are being propounded as new and promising approaches for managing dentistry conflicts. TE is now considered almost a practical, reproducible, and clinically safe therapy for regenerating different oral and dental tissues including either the whole dental organ or its various anatomical parts. TE necessarily constitutes three angles of stem cell (SC), scaffold, and essential growth factors (GFs). Generally, scaffolds can be made of decellularized scaffolds (usually containing the extra-cellular matrix (ECM) of target organs and tissues) or biologic scaffolds (containing natural polymer). The current study aims to review the studies conducted in the recent decade on decellularized and biological scaffolds and their potential applications in modern regenerative dentistry.

Bone injury represents an urgent clinical problem, and implantable bioscaffolds offer suitable means for replacing and regenerating damaged tissues. This paper proposes an in-situ foaming printing method employing material extrusion additive manufacturing technology and physical foaming to prepared poly(lactic acid)/chitin nanocrystals (CHNCs) microporous composite scaffolds, featuring pore sizes ranging from 9 ± 5 μm. This method offers a novel strategy for the preparation of poly(lactic acid)-based scaffolds with good biocompatibility. Material characterization and mechanical property testing demonstrated that the in-situ foaming printed PLA scaffolds exhibited excellent foam printability, and the expansion ratio and compression properties of the scaffolds could be adjusted by modifying the CHNCs concentration and the printing speed, achieving a compression modulus between 39.2 MPa and 54.3 MPa. Furthermore, at equivalent foaming multiplicity (1.5–2.6 times), the compression modulus increased by nearly 100 % compared to previously reported PLA-based foam scaffolds. Importantly, the PLA/CHNCs scaffolds produced via in-situ foaming exhibited superior biocompatibility compared to directly printed PLA scaffolds. This PLA/CHNCs composite scaffold provides a promising approach to addressing and repairing bone defects. • One-step preparation of microporous polylactic acid/chitin nanocrystals composite scaffolds by in-situ foaming printing • The prepared scaffolds have good pore structure and mechanical performance • The pore structure and mechanical properties can be adjusted by printing parameters • Compared with direct FDM printing, the scaffolds prepared by this method have superior biocompatibility [ABSTRACT FROM AUTHOR]

BACKGROUND: With the rapid development of 3D printing technology in tissue engineering, a variety of scaffold materials prepared by 3D printing are widely used in mandibular defect repair. 3D printing technology brings new possibilities for mandibular defect repair. OBJECTIVE: The 3D bionic bone scaffold material was constructed by low-temperature 3D printing technology, and the internal structure of the scaffold was precisely controlled, and the mechanical properties of the scaffold were analyzed. METHODS: Under the same volume, by changing the interlacing angle of the printed scaffold wire harness and the wire harness, low-temperature 3D printing technology was used to print silk fibroin/type I collagen/hydroxyapatite scaffolds with different angles (30°, 45°, 90°) and polycaprolactone/hydroxyapatite scaffolds (a total of 6 sets of scaffolds). The uniaxial compression mechanics experiment was loaded to 6 groups of scaffolds at a compression rate of 0.5%/s, compressed to 30% strain to observe the relationship between stress and strain. The stress relaxation experiment was applied to the three printing angles of silk fibroin/collagen I/hydroxyapatite scaffolds at a compression rate of 0.5%/s at 10%, 20%, and 30% strain, and the relaxation retention time was 3 hours to observe the relationship between stress and time. In the creep experiment, the silk fibroin/collagen I/hydroxyapatite scaffold with an angle of 90° was compressed and printed at a constant pressure of 2.5, 3.75, and 5 kPa, and the creep retention time was 3 hours to observe the relationship between strain and time. RESULTS AND CONCLUSION: (1) Uniaxial compression mechanics experiment: The mechanical properties of 3D printed silk fibroin/type I collagen/ hydroxyapatite scaffold and polycaprolactone/hydroxyapatite scaffold compression showed that the 90° scaffold had higher Young’s modulus than the 30° and 45° scaffolds under the same compression strain. (2) Stress relaxation experiment: When the compression rate, compression strain and compression angle were constant, the stress of silk fibroin/type I collagen/hydroxyapatite scaffold decreased rapidly with the extension of relaxation time, then slowly decreased. With the extension of relaxation time, the stress of the scaffold decreased rapidly in the beginning time (within 1 600 seconds), and in the later period (3 700 seconds). When the compression rate and compression strain were kept constant, the initial and stable stress values of silk fibroin/type I collagen/hydroxyapatite scaffolds with 90° printing angle were higher than those of scaffolds with 30° and 45° printing angle. When the compression rate and compression angle were constant, the initial and stable stress values of silk fibroin/type I collagen/hydroxyapatite scaffolds increased with the increase of compression strain. (3) Creep test: With the extension of creep time, the strain of 90° silk fibroin/type I collagen / hydroxyapatite scaffolds increased rapidly in the initial stage (within 500 seconds), then increased slowly, and finally leveled off. The strain range of the scaffolds was 35% to 55% at 2.5 kPa, and 43% to 57% at 3.75 kPa. The strain of the scaffold ranged from 45% to 57% under 5 kPa. [ABSTRACT FROM AUTHOR]

Traditional oral materials are mostly stable materials which are not affected by oral environment，while intelligent materials can adapt to various changes in the oral cavity and respond favorably，so they have become one of the research hotspots in recent years. As an environmentally sensitive polymer，intelligent hydrogel is an important type of smart materials and has been widely studied in stomatology. Based on the literature at home and abroad，this paper briefly reviews the definition and classification of intelligent hydrogels and the application of intelligent hydrogels in stomatology，and prospect the future development of these materials. [ABSTRACT FROM AUTHOR]

BACKGROUND: Bone tissue engineering is an effective bone defect repair program. Macrophages play an extremely important role in the immune response after implantation of tissue engineering materials. Interfering with its different polarization states has become a key means to regulate the local immune microenvironment. OBJECTIVE: To summarize the important role of macrophages in the immune response after biomaterial implantation and the research progress in promoting osteogenesis by regulating the polarization of macrophages in bone tissue engineering. METHODS: PubMed, Web of Science and CNKI were used to search the related articles published from 2016 to 2020. The retrieval article types were original research works and reviews. The search terms were “macrophage polarization, M2, scaffold, tissue engineering, foreign body response, implant, surface, bone” in English, and “macrophage polarization, M2, tissue engineering, foreign body response, implant, surface, bone” in Chinese. An inductive analysis was conducted in the selected articles on the latest research progress in this field. RESULTS AND CONCLUSION: The immune response plays an important role in tissue engineering and the regulation of the immune microenvironment is a key means of promoting osteogenesis in tissue engineered bone. The method of altering the physicochemical properties of the material, such as hydrophobicity, roughness and surface morphology has good stability for a long duration, achieves significant osteogenic improvements. Delivery of drugs, cytokines or bioactive ions has also worked well, but suffers from short release time and susceptibility to denaturation. Another strategy is regulation by engineered cellmacrophage crosstalk, where mesenchymal stem cells are highly immunomodulatory and can achieve immune modulation and bone repair promotion. The new study highlights the important role of exosomes to achieve controllable modulation of macrophage polarization and immune environment. [ABSTRACT FROM AUTHOR]

CeO 2 nanozymes have demonstrated the potential to enhance biological scaffolds with chemodynamic therapy. However, their catalytic efficacy is limited by the slow conversion of Ce 4+ to Ce 3+ and the lack of substrates like H 2 O 2 and H + . To address these challenges, we adopted a dual-pronged strategy that utilized the plasmonic resonance of Au nanoparticles and their glucose-oxidase mimicry to boost electron and hydrogen transfer. Specifically, we integrated Au/CeO 2 nanozymes into poly-l-lactic acid scaffolds via selective laser sintering. This conversion of Ce 3+ to Ce 4+ in the scaffolds enhanced the reduction of H 2 O 2 to a hydroxyl radical, inducing oxidative stress in tumor cells. The Au nanoparticles played a crucial role in boosting the Ce 3+ /Ce 4+ catalytic cycle by providing both the energy and the catalytic substrates. They recycled Ce 4+ back to Ce 3+ by exploiting plasmonic-induced hot electrons and catalyzed glucose oxidation to supply H 2 O 2 and H + . Our nanoscale and atomic-scale simulations confirmed that the Au/CeO 2 hybrid structure utilized near-field coupling to amplify the plasmonic resonance and the Au-O-Ce bridge reduced the electron transfer barrier. Consequently, the Au/CeO 2 scaffold decreased the activation energy from 22.57 to 9.92 kJ/mol. These findings highlight the significant promise of the Au/CeO 2 nanozyme scaffold for NIR-enhanced chemodynamic therapy.

Background: Owing to limited self-healing capacity, failure of rotator cuff tendon healing is a common complication after surgery. Biological scaffolds have garnered attention owing to their potential to enhance healing outcomes. Purpose: To verify the effect of the decellularized umbilical cord Wharton jelly (DUCWJ) scaffold as a bridging scaffold in a rabbit model of acute rotator cuff tendon defect. Study Design: Controlled laboratory study. Methods: We fabricated a DUCWJ scaffold using a physicochemical decellularized method, evaluating changes in the umbilical cord Wharton jelly before and after decellularization. Scanning electron microscopy and biomechanical testing were performed to determine the microstructure and mechanical properties. We assessed cytocompatibility and cell regulatory behavior of the scaffold toward tendon stem/progenitor cells (TSPCs). A supraspinatus tendon defect was created in 54 New Zealand White rabbits, allocated to the DUCWJ scaffold repair group and the negative control group (without scaffold). Histology, reverse transcription polymerase chain reaction, and biomechanical tensile strength were assessed at 4, 8, and 12 weeks postoperatively. Results: Decellularization completely removed cells from the umbilical cord Wharton jelly, retained a considerable amount of glycosaminoglycan and collagen, and preserved the microstructure and tensile strength. The DUCWJ scaffold facilitated migration and proliferation of TSPCs in vitro. Tendon-related gene expression revealed that the DUCWJ scaffold could maintain the tenocyte phenotype of TSPCs. In the in vivo study, the DUCWJ scaffold improved tendon healing and enhanced the biomechanical strength of repaired tendons. Histological evaluation scores of the DUCWJ group were significantly higher than those of the negative control at 4, 8, and 12 weeks after surgery (P <.05). In repaired tendon tissues, reverse transcription polymerase chain reaction findings revealed that the DUCWJ scaffold stimulated tendon development and maturation. Furthermore, an overall increase in ultimate load and tensile modulus was noted over time; the DUCWJ group presented better results than the negative control group (P <.05). Conclusion: The DUCWJ scaffold has an excellent 3-dimensional porous structure, good biocompatibility, and fundamental biomechanical characteristics, and it promotes migration, attachment, and proliferation of TSPCs. The in vivo animal study demonstrated that the DUCWJ scaffold has potential for tendon regeneration in an acute rotator cuff tendon defect model Clinical Relevance: DUCWJ scaffolds have potential as a regenerative material to augment rotator cuff healing in the clinical setting. [ABSTRACT FROM AUTHOR]

Current strategies in urinary bladder augmentation include use of gastrointestinal segments, however, the technique is associated with inevitable complications. An acellular biologic scaffold seems to be a promising option for urinary bladder augmentation. The aim of this study was to evaluate the utility of bladder acellular matrix (BAM) for reconstruction of clinically significant large urinary bladder wall defects in a long‐term porcine model. Urinary bladders were harvested from 10 pig donors. Biological scaffolds were prepared by chemically removing all cellular components from urinary bladder tissue. A total of 10 female pigs underwent hemicystectomy and subsequent bladder reconstruction with BAM. The follow‐up study was 6 months. Reconstructed bladders were subjected to radiological, macroscopic, histological, immunohistochemical, and molecular evaluations. Six out of ten animals survived the 6‐month follow‐up period. Four pigs died during observation due to mechanical failure of the scaffold, anastomotic dehiscence between the scaffold and native bladder tissue, or occluded catheter. Tissue engineered bladder function was normal without any signs of postvoid residual urine in the bladder or upper urinary tracts. Macroscopically, graft shrinkage was observed. Urothelium completely covered the luminal surface of the graft. Smooth muscle regeneration was observed mainly in the peripheral graft region and gradually decreased toward the center of the graft. Expression of urothelial, smooth muscle, blood vessel, and nerve markers were lower in the reconstructed bladder wall compared to the native bladder. BAM seems to be a promising biomaterial for reconstruction of large urinary bladder wall defects. Further research on cell‐seeded BAM to enhance urinary bladder regeneration is required. [ABSTRACT FROM AUTHOR]

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BACKGROUND: The combination of bioelectrospray and electrospinning can promote the direct integration of living cells and scaffold materials, and can distribute the cells evenly among scaffold fibers, which is a promising alternative to the preparation of scaffold containing cells. OBJECTIVE: To investigate the feasibility using multiple methods to prepare poly(lactide-co-glycolide) (PLGA) three-dimensional scaffolds rich in adipose derived stem cells (ASCs) as urethral tissue reconstruction materials. METHODS: The ASCs were integrated into PLGA by electrospinning and cell bio-electrospray method. The cell scaffold PLGA-ASCs was obtained. The pure PLGA scaffold was prepared by electrospinning. The microstructure, in vitro degradation, mechanical properties and residual solvent content of the two scaffolds were detected. The cell viability of PLGA-ASCs was detected by MTT assay. PLGA-ASCs were cultured in 37°C cell incubator for 1, 7 and 15 days. MTT assay was used to detect cell viability. Scanning electron microscopy and confocal microscopy were used to observe the growth and diffusion of ASCs on the scaffolds. RESULTS AND CONCLUSION: (1) Scanning electron microscopy showed that the fiber surface of PLGA-ASCs and PLGA scaffolds was smooth, and ASCs were randomly distributed on PLGA-ASCs scaffolds. The average fiber diameter and thickness of PLGA-ASCs scaffolds were larger than those of PLGA scaffolds. The cell survival rate in PLGA-ASCs scaffolds was (87.0±4.4)%, and the cell integration efficiency in PLGA-ASCs scaffolds was 28%. (2) In vitro degradation experiment showed that weight average molecular weight of PLGA scaffolds decreased rapidly in the first 15 days. The weight average molecular weight of PLGA-ASCs scaffolds decreased rapidly on 15-45 days. There was no difference in weight average molecular weight between the two groups at 45 days. (3) Young’s modulus, maximum load, and maximum elongation of PLGA-ASCs scaffolds were lower than those of PLGA scaffolds. (4) During 1-7 days of culture, the number of cells in PLGA-ASCs scaffolds gradually increased, and the number of cells in PLGA-ASCs scaffolds increased gradually from 7 to 15 days. (5) The results of scanning electron microscope observation and confocal microscope showed that the number of cells in PLGA-ASCs scaffolds increased gradually and integrated with the scaffolds with the extension of culture time. (6) The results showed that PLGA-ASCs had good physical and chemical properties and biological activity, and could be used as urethral tissue reconstruction materials. [ABSTRACT FROM AUTHOR]

Decellularization approaches have been commonly used as alternative techniques to reconstruct tissues. However, due to the complex tissue compartmentation of the larynx, the decellularization process may not retain the characteristics necessary for the successful recreation of the larynx. The aim of this study was to assess the effect of the decellularization process on the framework of the human cadaveric larynx generally and the cricoarytenoid joint specifically. In this work, five freshly frozen human cadaveric larynges were decellularized utilizing a protocol that was previously demonstrated to be effective in decellularizing a porcine larynx. The decellularization protocol included: biological, chemical, and physical decellularization methods. Each specimen served as its own control to assess changes after decellularization. Studies and measurements included: histological, using Hematoxylin and Eosin (H&E) and Live/Dead™ stains; DNA quantification; micro‐computed tomography (μ‐CT) imaging; and biomechanical testing of the cricoarytenoid joints. The decellularization protocol took 12 days for each specimen. Microscopy of H&E stained samples demonstrated substantial removal of cells with preservation of the extracellular matrix that was more evident in cartilage than muscle specimens. Confocal microscope images of Live/Dead™ stained specimens also demonstrated almost complete removal of cells. Pre‐decellularization cartilage‐DNA quantity range was 27.0 to 336.8 ng/mg while post‐decellularization DNA quantity range was 0 to 30.4 ng/mg (p = 0.031). For muscles, pre‐decellularization DNA quantity range was 150.0 to 3,384.6 ng/mg, while post‐decellularization DNA quantity range was 0 to 45.5 ng/mg (p = 0.031). μ‐CT demonstrated preservation of the cartilaginous framework with a slight reduction of cricoarytenoid joint space. Furthermore, μ‐CT demonstrated no significant reduction in the Housefield unit (p = 0.25) and mineral density (p = 0.25) after decellularization. Biomechanical testing demonstrated a non‐significant reduction of forces required for anterior displacement of the arytenoid (mean reduction of forces, 0.1 ± 0.2 N, p = 0.16) and forces required for posterior displacement of the arytenoid (mean reduction of forces, 0.2 ± 0.3 N, p = 0.05). This study demonstrates effective decellularization of human larynges as evidenced by significant DNA depletion and preservation of extracellular matrix, which are outcomes that are required for a biological scaffold to regenerate a non‐immunogenic larynx. The decellularization process caused minimal weakness in the cricoarytenoid joints due to treatment with multiple detergents and enzymes in the decellularization protocol. [ABSTRACT FROM AUTHOR]

Objective To develop a novel decellularized extracellular matrix (ECM) bioscaffold derived from human cirrhotic liver tissues and construct a 3-dimensional cell culture system using this bioscaffold material. Methods Clinical samples of cirrhotic liver tissues were collected from patients undergoing liver transplantation for hepatic cirrhosis. The cirrhotic liver tissues were cleansed, cut into small tissue blocks (5 mm×5 mm×5 mm), and agitated in deionized water and detergents to obtain decellularized cirrhotic liver scaffold. Human primary human hepatocytes (PHHs) were seeded into the prepared ECM scaffold and cultured continuously for 9 d. Histological studies of the seeded cells were performed to assess the cell engraftment, and qPCR was used to detect the expression of the liver-specific genes in the cultured cells. Results The cirrhotic liver tissue became transparent after decellularization, and HE staining and scanning electron microscopy showed no residual nuclei in the bioscaffold. Residual DNA identification showed that the scaffold material had a residue DNA level less than 10 ng/mg of the tissue. After 9 d of continuous culture in the ECM scaffold, the PHHs showed good engraftment as shown by HE staining; the results of qPCR showed that the cells cultured in this 3D culture system expressed higher levels of liver-specific genes as compared with the cells in conventional 2D culture. Conclusion We successfully construct decellularized ECM bioscaffold derived from human cirrhotic liver tissues and confirmed the feasibility of 3D cell culture using this new bioscaffold material.

BACKGROUND: With the development of bone tissue engineering, the role of scaffold materials has become more and more important. Polycaprolactone and its composite materials have also increasingly attracted researchers to become one of the research highlights in this field. OBJECTIVE: To introduce the basic properties and synthesis methods of polycaprolactone, to summarize the research status of polycaprolactone and its composite materials in the field of bone tissue engineering, and to prospect the future development and research direction. METHODS: These articles published from 1950 to 2020 in Web of Science database were retrieved by using the search terms “PCL, PCL composites, bone tissue engineering, scaffold, bone, PCL synthesis”, taking “and” as the logical combination relationship. Totally 253 articles were initially obtained, and finally 52 articles were reviewed and analyzed after careful reading and selection. RESULTS AND CONCLUSION: (1) Pure polycaprolactone materials have certain shortcomings in bone tissue engineering. Due to their easy chemical modification and physical modification, polycaprolactone composite undoubtedly has become one of the candidate materials for bone tissue engineering scaffolds. (2) Due to the excellent solubility and thermal properties of polycaprolactone, it can be applied to a variety of scaffold preparation technologies. The appropriate scaffold preparation technology can be selected according to the application site. A variety of scaffold preparation technologies also broaden the application field of polycaprolactone, and there are also developed some novel technologies, so scaffold preparation technology should also attract the attention researchers. (3) For the modification direction of polycaprolactone, the modification of inorganic substances and natural or synthetic polymers has received extensive attention. (4) In terms of experimental research methods, researchers should pay attention to introducing more kinds of experimental cells and experimental models in accordance with clinical needs. [ABSTRACT FROM AUTHOR]

Tissue engineering which is applied in regenerative medicine has three basic components: cells, scaffolds and growth factors. This multidisciplinary field can regulate cell behaviors in different conditions using scaffolds and growth factors. Scaffolds perform this regulation with their structural, mechanical, functional and bioinductive properties and growth factors by attaching to and activating their receptors in cells. There are various types of biological extracellular matrix (ECM) and polymeric scaffolds in tissue engineering. Recently, many researchers have turned to using biological ECM rather than polymeric scaffolds because of its safety and growth factors. Therefore, selection the right scaffold with the best properties tailored to clinical use is an ideal way to regulate cell behaviors in order to repair or improve damaged tissue functions in regenerative medicine. In this review we first divided properties of biological scaffold into intrinsic and extrinsic elements and then explain the components of each element. Finally, the types of scaffold storage methods and their advantages and disadvantages are examined. [ABSTRACT FROM AUTHOR]

BACKGROUND: In recent years, more and more scaffold materials have been used to repair soft tissue defects, and the clinical repair effect of soft tissue defects is strongly associated with the source and performance of materials. OBJECTIVE: To summarize the research progress of preparation and application of different biological scaffolds in the field of oral and maxillofacial soft tissue defect repair. METHODS: PubMed and Medline were searched for articles published from 1966 to 2019 with the English key words of “materials, scaffold, biological scaffold, soft tissue, coloboma, tissue engineering, review”. Chinese journal full-text database and Chinese science citation database were retrieved for articles published from 2003 to 2019 with key words of “material, scaffold, biological scaffold, soft tissue, defect, tissue engineering, review”. RESULTS AND CONCLUSION: Natural bio-scaffold materials are directly derived from organisms with pretty biocompatibility. Natural bio-scaffold materials can release cytoactive factors, promote cell adhesion, proliferation and differentiation, and can be combined with synthetic polymer materials with controllable properties to form composite scaffolds, which is an ideal scaffold material for repairing soft tissue defects of oral and maxillofacial regions. Nanomaterials have higher biological activity than other scaffold materials and can promote the adhesion and proliferation of seed cells, providing ideal three-dimensional space for cell growth, but their applications are currently mainly reflected in bone tissue repair, and the applications in soft tissue repair are very few. At present, there are many researches on natural biological scaffold materials in oral and maxillofacial soft tissue repair, mainly including small intestinal submucosa, acellular dermal matrix and acellular vascular scaffolds. The combination of natural biological scaffold materials and synthetic polymer materials will be a major research trend in materials for repairing oral and maxillofacial soft tissue defects. [ABSTRACT FROM AUTHOR]

The management of large rotator cuff tears in patients without evidence of glenohumeral arthritis is challenging and controversial. We wished to investigate the viability of Graft Jacket® augmentation and assess the clinical and radiological outcomes in a prospective study with a select cohort of patients. All procedures were performed by a single shoulder surgeon over a three-year period. Inclusion criteria were patients with large cuff tears (size 3–5 cm) not amenable to end-to-end repair. Patients with radiographic evidence of glenohumeral arthritis or cuff tear arthropathy were excluded. Open rotator cuff repair followed by bridging with GraftJacket® Regenerative Tissue Matrix was performed. Outcome was assessed with Constant scores (CS), QuickDash (QD) and Oxford Shoulder scores (OSS) at minimum twenty-two months and ultrasound assessment at nine months post-operatively. Thirteen patients were identified who fit inclusion criteria (one bilateral). No patients were lost to follow up. At final follow-up thirteen shoulders had achieved function range of movement. Mean CS was 83 (range 70–100), mean Quick DASH was 5.4 (range 0–18.2), and mean OSS was 46 (range 41–48). Shoulder ultrasound revealed an intact Graft Jacket® in these patients. One patient had lower functional movement and worse CS (34), QD (34.1) and OSS (25) and ultrasound assessment identified a re-rupture. This study indicates that augmentation of large rotator cuff repairs with a GraftJacket® scaffold is a viable option and has good functional results and sustained viability. Level 4. [ABSTRACT FROM AUTHOR]

Pericardium closure after cardiac surgery is recommended to prevent postoperative adhesions to the sternum. Synthetic materials have been used as substitutes, with limited results because of impaired remodeling and fibrotic tissue formation. Urinary bladder matrix (UBM) scaffolds promote constructive remodeling that more closely resemble the native tissue. The aim of the study is to evaluate the host response to UBM scaffolds in a porcine model of partial pericardial resection. Twelve Landrace pigs were subjected to a median sternotomy. A 5 × 7 cm pericardial defect was created and then closed with a 5 × 7 cm multilayer UBM patch (UBM group) or left as an open defect (control group). Animals were survived for 8 wk. End points included gross morphology, biomechanical testing, histology with semiquantitative score, and cardiac function. The UBM group showed mild adhesions, whereas the control group showed fibrosis at the repair site, with robust adhesions and injury to the coronary bed. Load at failure (gr) and stiffness (gr/mm) were lower in the UBM group compared with the native pericardium (199.9 ± 59.2 versus 405.3 ± 99.89 g, P = 0.0536 and 44.23 ± 15.01 versus 146.5 ± 24.38 g/mm, P = 0.0025, respectively). In the UBM group, the histology resembled native pericardial tissue, with neovascularization, neofibroblasts, and little inflammatory signs. In contrast, control group showed fibrotic tissue with mononuclear infiltrates and a lack of organized collagen fibers validated with a histologic score. Both groups had normal ultrasonography results without cardiac motility disorders. In this setting, UBM scaffolds showed appropriate features for pericardial repair, restoring tissue properties that could help reduce postsurgical adhesions and prevent its associated complications. [ABSTRACT FROM AUTHOR]

With the development of technology, tissue engineering (TE) has been widely applied in the medical field. In recent years, due to its accuracy and the demands of solid freeform fabrication in TE, three-dimensional printing, also known as additive manufacturing (AM), has been applied for biological scaffold fabrication in craniofacial and dental regeneration. In this review, we have compared several types of AM techniques and summarized their advantages and limitations. The range of printable materials used in craniofacial and dental tissue includes all the biomaterials. Thus, basic and clinical studies were discussed in this review to present the application of AM techniques in craniofacial and dental tissue and their advances during these years, which might provide information for further AM studies in craniofacial and dental TE.

• 3D acellular matrix scaffold (hECM) was produced from decellularized human adipose. • Human adipose stem cells (ASCs) were isolated from the same tissue. • hECM was recellularized with ASCs and then cultured under chondrogenic conditions. • A new cartilage-like tissue was engineered in vitro. Here, the in vitro engineering of a cartilage-like tissue by using decellularized extracellular matrix scaffold (hECM) seeded with human adipose stem cells (hASCs) which can both be isolated from the human waste adipose tissue is described. Cell-free, highly fibrous and porous hECM was produced using a protocol containing physical (homogenization, centrifugation, molding) and chemical (crosslinking) treatments, characterized by SEM, histochemistry, immunohistochemistry and in vitro cell interaction study. A construct of hECM seeded with hASCs was cultured in chondrogenic medium (with TGF- β 3 and BMP-6) for 42 days. SEM and histology showed that the biological scaffold was highly porous and had a compact structure suitable for handling and subsequent cell culture stages. Cells successfully integrated into the scaffold and had good cellular viability and continuity to proliferate. Constructs showed the formation of cartilage-like tissue with the synthesis of cartilage-specific proteins, Collagen type II and Aggrecan. Dimethylmethylene blue dye binding assay demonstrated that the GAG content of the constructs was in tendency to increase with time confirming chondrogenic differentiation of hASCs. The results support that human waste adipose tissue is an important source for decellularized hECM as well as stem cells, and adipose hECM scaffold provides a suitable environment for chondrogenic differentiation of hASCs. [ABSTRACT FROM AUTHOR]

An important component of tissue engineering (TE) is the supporting matrix upon which cells and tissues grow, also known as the scaffold. Scaffolds must easily integrate with host tissue and provide an excellent environment for cell growth and differentiation. Human amniotic membrane (hAM) is considered as a surgical waste without ethical issue, so it is a highly abundant, cost-effective, and readily available biomaterial. It has biocompatibility, low immunogenicity, adequate mechanical properties (permeability, stability, elasticity, flexibility, resorbability), and good cell adhesion. It exerts anti-inflammatory, antifibrotic, and antimutagenic properties and pain-relieving effects. It is also a source of growth factors, cytokines, and hAM cells with stem cell properties. This important source for scaffolding material has been widely studied and used in various areas of tissue repair: corneal repair, chronic wound treatment, genital reconstruction, tendon repair, microvascular reconstruction, nerve repair, and intraoral reconstruction. Depending on the targeted application, hAM has been used as a simple scaffold or seeded with various types of cells that are able to grow and differentiate. Thus, this natural biomaterial offers a wide range of applications in TE applications. Here, we review hAM properties as a biocompatible and degradable scaffold. Its use strategies (i.e., alone or combined with cells, cell seeding) and its degradation rate are also presented.

In this study, NBG was successfully achieved through a sol-gel technique, and to further improve its dispersibility, a crylate coupling agent was coupled onto the surface of the NBG. The 3-(Trimethoxysilyl)Propylmethacrylate coupling agent was used to the surface modification of the synthesized NBG by a wet-chemical method in a dynamic inert nitrogen atmosphere. The surface properties of the biomaterials before and after modification were characterized and compared using FTIR and AFM techniques. The characteristic peaks in FTIR spectra indicated that –CH2, –CH3 and C=O groups appeared on the surface of modified NBG, and also, AFM analysis revealed that the dispersibility of surface modified NBG was improved, significantly. The above results proved that the desired groups of 3-(Trimethoxysilyl)Propyl methacrylate had been covalently bonded onto the surface of NBG. Besides, a nanocomposite scaffold was synthesized using the synthesized NBG and polyurethane foam as raw materials. The morphology of pores, porosity contents, compress strength and bioactivity of the scaffold were studied. The results showed that the biological scaffolds for use in bone tissue engineering with the basic requirements (90% porosity and 200-600 μm pore diameter) were successfully prepared. The polymer component had no effect on the relationship between the scaffold pores and bioactivity of bioglass nanoparticles. Improvement of compressive strength and proper bioactivity of the resulted scaffold showed that it is an acceptable candidate for biomaterials applications.