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Abstract Replicating the architecture of extracellular matrices (ECM) is crucial in tissue engineering to support tissues’ natural structure and functionality. The ECM’s structure plays a significant role in directing cell alignment. Electrospinning is an effective technique for fabricating nanofibrous substrates that mimic the architecture of extracellular matrices (ECM). This study aims to evaluate the efficacy of resin 3D-printed scaffolds made from a low-conductivity material (i.e., a resin composed of methacrylated oligomers, monomers, and photoinitiators) in directing the alignment of electrospun polycaprolactone (PCL) nanofibers. Six 3D-printed scaffolds were fabricated using stereolithography (SLA) technology and strategically positioned on an aluminum foil collector plate during electrospinning. The structured geometry of the scaffolds, rather than the local electric field distribution, is hypothesized to guide nanofiber alignment. Images acquired through the scanning electron microscopy (SEM) were used to analyze and statistically quantify the nanofibrous scaffolds to evaluate the alignment of nanofibers over the scaffolds compared to a set of randomly deposited control nanofiber samples in the absence of the 3D printed scaffolds. SEM images also showed significant alignment of nanofibers within the pores of scaffolds, using histograms as a means for indicating the distribution of orientation angles. Statistical analysis revealed that this distribution deviates from normality due to the deviations in the tails and the existence of relatively smaller peaks at angles relative to 0°, particularly within a range of ± 50° and ± 40°. It is further found that the average peak orientation angle relative to 0° had a maximum probability of 0.014. Furthermore, the statistical analysis confirmed the distribution and significant differences in orientation between test samples with 3D-printed scaffolds and control samples. These findings demonstrate the effectiveness of resin 3D-printed scaffolds, particularly their geometric filtering effect, leading to controlled nanofiber alignment, which is proposed to be beneficial for enhancing cell adhesion, proliferation, and cell migration in tissue engineering applications.

Abstract Cell therapy has emerged as a viable approach for treating damaged organs or tissues, particularly with advancements in stem cell research and regenerative medicine. The innovative technique of cell sheet engineering offers the potential to create a cell-dense lamellar structure that preserves the extracellular matrix (ECM) secreted by cells, along with the cell-matrix and intercellular junctions formed during in vitro cultivation. In recent years, significant progress has been made in developing cell sheet engineering technology. A variety of novel materials and methods were utilized for enzyme-free cell detachment during the cell sheet formation process. The complexity of cell sheet structures increased to meet advanced usage demands. This review aims to provide an overview of the preparation methods and types of cell sheets, thereby enhancing the understanding of this rapidly evolving technology and offering a fresh perspective on the development and future application of cell sheet engineering. Graphical Abstract

Abstract Urogenital reconstructive malformation surgery is sometimes hampered by lack of tissue for the repair. We have previously shown that autologous micrografting allows for single-staged scaffold cellularization after surgical implantation. Here, a collagen-based scaffold reinforced with biodegradable mesh and a stent was implanted as a bladder conduit in ten full-grown female minipigs. We aimed to assess short-term regenerative outcomes, safety, and feasibility of implanting tubular urinary micrografted scaffolds versus acellular controls. Five scaffolds were embedded with autologous urothelial micrografts harvested perioperatively. After six weeks, all animals were assessed by cystoscopy, CT-urography, and microanatomical assessment of the urinary conduits. The procedure proved technically feasible within the confines of a regular surgical theater, with duration-times comparable to corresponding conventional procedures. No animals experienced postoperative complications, and all implanted conduits were patent at follow-up. Improved tissue regeneration was observed in the micrografted conduits compared with the acellular controls, including increased luminal epithelialization, increased cell proliferation, decreased cell apoptosis, and increased conduit vascularization. We concluded that single-staged on-site construction and implantation of tissue engineered urinary conduits proved feasible and safe, with improved regenerative potentials in micrografted conduits. This study presents a new approach to urinary conduits, and merits further investigations for advancement towards clinical translation.

Cementum plays a crucial role in linking periodontal and dental tissues and maintaining tooth root stability. Regenerating cementum is essential for functional periodontal tissue regeneration. It is a significant focus in tissue engineering. Periodontal disease, prevalent among the middle-aged and elderly, can severely impact overall health. Effective periodontal tissue regeneration is vital for enhancing the elderly's health and quality of life. Despite the progress, the lack of ideal scaffold materials and methods makes cementum regeneration a persistent challenge. This review discusses the current state of cementum tissue engineering materials and addresses existing challenges, providing a foundation for future scaffold material development.

In clinical terms, end-stage liver disease is a group of liver diseases that includes advanced liver disease, liver failure, and decompensated cirrhosis. Liver transplantation has been the most effective treatment for cirrhosis. The limited number of available and suitable living liver donors is a significant limitation in liver transplantation. Acute or chronic rejection could be the cause of liver transplant failure. To overcome rejection, usage of the long-term immunosuppressive drug is a standard post-transplant regimen. However, this therapy can increase the risk of severe viral or fungal infection and malignancy. Various attempts were made to address the liver transplant shortage. One of them is liver tissue engineering. This research was conducted with an artificial liver prototype of Stem Cell Hepatic Intuitive Apparatus (SHiNTA) with a perfusion bioreactor, whose manufacturing process is simple in the form of a liver microstructure consisting of differentiated hepatocytes from an hiPSCs from a modification of the Blackford protocol in a liver biologic scaffold. Liver biologic scaffolds were made from pieces of rabbit liver stored in the Stem Cell and Tissue Engineering (SCTE) laboratory, Fakultas Kedokteran Universitas Indonesia, by decellularization. This study aimed to develop the SHiNTA BALs to sustain the viability of hiPSC-derived hepatocytes in the artificial liver prototype. SHiNTA artificial liver prototype with a perfusion bioreactor connected to a perfusion pump with a specific perfusion rate of 2mL/min showed a higher cell count and confluence, with evenly distributed in the extracellular matrix than SHiNTA blood bag with orbital shaker group up to day 7. Furthermore, the SHiNTA artificial liver with perfusion bioreactor showed a positive signal of cell maturation in the scaffold (ASGPR, HNF4- , and CEBP- ) through immunofluorescence.

Microparticles have demonstrated value for regenerative medicine. Attempts in this field tend to focus on the development of intelligent multifunctional microparticles for tissue regeneration. Here, inspired by erythrocytes-associated self-repairing process in damaged tissue, we present novel biomimetic erythrocyte-like microparticles (ELMPs). These ELMPs, which are composed of extracellular matrix-like hybrid hydrogels and the functional additives of black phosphorus, hemoglobin, and growth factors (GFs), are generated by using a microfluidic electrospray. As the resultant ELMPs have the capacity for oxygen delivery and near-infrared-responsive release of both GFs and oxygen, they would have excellent biocompatibility and multifunctional performance when serving as microscaffolds for cell adhesion, stimulating angiogenesis, and adjusting the release profile of cargoes. Based on these features, we demonstrate that the ELMPs can stably overlap to fill a wound and realize controllable cargo release to achieve the desired curative effect of tissue regeneration. Thus, we consider our biomimetic ELMPs with discoid morphology and cargo-delivery capacity to be ideal for tissue engineering.

The developments of nano-roughness surface textures are important to implement enhanced osseointegration, cell adhesion, and proliferation in polymers for biomedical applications such as tissue engineering scaffolds and orthopaedic implants. The hydrophilicity of the polymeric implants is a crucial factor for cell adhesion, which can be improved via adapting the roughness of the surface. This study explores the surface modification of poly (lactic acid) (PLA) polymer through an alkaline wet etching process, varying alkaline concentration and etching time under both room temperature and elevated conditions. The main objective is to refine the PLA surface through wet etching, altering its properties for potential use in biomedical contexts. The assessment of surface roughness is conducted through scanning electron microscopy (SEM), atomic force microscopy (AFM), and fourier-transform infrared spectroscopy (FTIR). These techniques offer a comprehensive analysis of surface topography, nanoscale roughness, and potential chemical changes resulting from the wet etching process. The nano-roughness of treated 3D printed PLA was increased by 1.4 times compared to the control 3D printed PLA. The research contributes to the broader field of biomaterial engineering, laying the groundwork for subsequent investigations that will focus on applying the derived conclusions to enhance PLA’s biocompatibility and functionality in tissue engineering and orthopaedic applications.

MoS2 is a substance, highly valued for its two-dimensional nanostructure and diverse physical and chemical properties. This review examines the advancements achieved in biomedical applications through the integration of molybdenum disulfide (MoS2), and the state-of-the-art area of 3D printing technology. It initially outlines MoS2 synthesis routes and techniques to tailor its properties. The review explores how MoS2 properties underpin its biological significance, thereby facilitating its therapeutic, tissue engineering, and biosensing applications. Emphasis is placed on the emerging area of 3D printing, assessing its potential when combined with MoS2 to produce customized materials for biomedical purposes. Strategies to create foam topologies and electrocatalytically active filaments in 3D-printed constructs are explained. The enhanced mechanical strength, conductivity, and therapeutic efficacy observed in 3D-printed MoS2 structures foreshadow new developments in healthcare, including the advent of biocompatible implants for regenerative medicine and tissue engineering. Further results show how innovations have been made in biosensing areas leveraging MoS2 3D printing. These insights, grounded in scientific research, medical practices, and technological advancements, position MoS2 as a flexible and innovative material with diverse applications across various biomedical sectors.

The muscle tendon junction (MTJ) transmits the force generated by the muscle to the tendon and ultimately to the bone. Tears and strains commonly occur at the MTJ where regeneration is limited due poor vascularisation and the complexity of the tissue. Currently treatments for a complete MTJ tear are often unsuccessful. The creation of a tissue engineered MTJ would therefore be beneficial in the development of a novel treatment. In this study, aligned electrospun polycaprolactone fibres were fabricated and human myoblasts and tenocytes were cultured on the scaffold. The effect of 10 % cyclic strain and co-culture of myoblasts and tenocytes on the MTJ formation was investigated. The application of strain significantly increased cell elongation, and MTJ marker gene expression. Co-culture of myoblasts and tenocytes with strain induced higher MTJ marker gene expression compared with myoblasts and tenocytes cultured separately. Paxillin and collagen 22, naturally found in the MTJ, were also produced when cells were combined and grown in a 10 % strain environment. For the first time these results showed that the combination of the strain and co-culture of myoblasts and tenocytes promotes gene expression and production of proteins that are found in the MTJ.

Mg is a typical biodegradable metal widely used for biomedical applications due to its considerable mechanical properties and bioactivity. Biodegradable polymers have attracted great interest owing to their favorable processability and inclusiveness. However, it is challenging for the degradation rates of Mg or polymers to precisely match tissue repair processes, and the significant changes in local pH during degradation hinder tissue repair. The concept of combining Mg with polymers is proposed to overcome the shortcomings of materials, aiming to meet repair needs from various aspects such as mechanics and biology. Therefore, it is essential to systematically understand the behavior of biodegradable Mg/polymer composite (BMPC) from the design, manufacturing, mechanical properties, degradation, and biological effects. In this review, we elaborate on the design concepts and manufacturing strategies of high-strength BMPC, the “structure-function” relationship between the microstructures and mechanical properties of composites, the variation in the degradation rate due to endogenous and exogenous factors, and the establishment of advanced degradation research platform. Additionally, the interplay among composite components during degradation and the biological function of composites under non-responsive/stimuli-responsive platforms are also discussed. Finally, we hope that this review will benefit future clinical applications of “structure-function” integrated biomaterials.

Irregular articular cartilage injury is a common type of joint trauma, often resulting from intense impacts and other factors that lead to irregularly shaped wounds, the limited regenerative capacity of cartilage and the mismatched shape of the scaffods have contributed to unsatisfactory therapeutic outcomes. While injectable materials are a traditional solution to adapt to irregular cartilage defects, they have limitations, and injectable materials often lack the porous microstructures favorable for the rapid proliferation of cartilage cells. In this study, an injectable porous polyurethane scaffold named PU-BDO-Gelatin-Foam (PUBGF) was prepared. After injection into cartilage defects, PUBGF forms in situ at the site of the defect and exhibits a dynamic microstructure during the initial two weeks. This dynamic microstructure endows the scaffold with the ability to retain substances within its interior, thereby enhancing its capacity to promote chondrogenesis. Furthermore, the chondral repair efficacy of PUBGF was validated by directly injecting it into rat articular cartilage injury sites. The injectable PUBGF scaffold demonstrates a superior potential for promoting the repair of cartilage defects when compared to traditional porous polyurethane scaffolds. The substance retention ability of this injectable porous scaffold makes it a promising option for clinical applications.

Cells self-organize into functional, ordered structures during tissue morphogenesis, a process that is evocative of colloidal self-assembly into engineered soft materials. Understanding how intercellular mechanical interactions may drive the formation of ordered and functional multicellular structures is important in developmental biology and tissue engineering. Here, by combining an agent-based model for contractile cells on elastic substrates with endothelial cell culture experiments, we show that substrate deformation-mediated mechanical interactions between cells can cluster and align them into branched networks. Motivated by the structure and function of vasculogenic networks, we predict how measures of network connectivity like percolation probability and fractal dimension as well as local morphological features including junctions, branches, and rings depend on cell contractility and density and on substrate elastic properties including stiffness and compressibility. We predict and confirm with experiments that cell network formation is substrate stiffness dependent, being optimal at intermediate stiffness. We also show the agreement between experimental data and predicted cell cluster types by mapping a combined phase diagram in cell density substrate stiffness. Overall, we show that long-range, mechanical interactions provide an optimal and general strategy for multicellular self-organization, leading to more robust and efficient realizations of space-spanning networks than through just local intercellular interactions.

Sustained release of vaccine components is a potential method to boost efficacy compared with traditional bolus injection. Here, we show that a biodegradable hyaluronic acid (HA)-scaffold, termed HA cryogel, mediates sustained antigen and adjuvant release in vivo leading to a durable immune response. Delivery from subcutaneously injected HA cryogels was assessed and a formulation which enhanced the immune response while minimizing the inflammation associated with the foreign body response was identified, termed CpG-OVA-HAC2. Dose escalation studies with CpG-OVA-HAC2 demonstrated that both the antibody and T cell responses were dose-dependent and influenced by the competency of neutrophils to perform oxidative burst. In immunodeficient post-hematopoietic stem cell transplanted mice, immunization with CpG-OVA-HAC2 elicited a strong antibody response, three orders of magnitude higher than dose-matched bolus injection. In a melanoma model, CpG-OVA-HAC2 induced dose-responsive prophylactic protection, slowing the tumor growth rate and enhancing overall survival. Upon rechallenge, none of the mice developed new tumors suggesting the development of robust immunological memory and long-lasting protection against repeat infections. CpG-OVA-HAC2 also enhanced survival in mice with established tumors. The results from this work support the potential for CpG-OVA-HAC2 to enhance vaccine delivery.

Prostate cancer (PCa) is an increasingly prevalent health problem in the developed world. Effective treatment options exist for localized PCa, but metastatic PCa has fewer treatment options and shorter patient survival. PCa and bone health are strongly entwined, as PCa commonly metastasizes to the skeleton. Since androgen receptor signaling drives PCa growth, androgen-deprivation therapy whose sequelae reduce bone strength constitutes the foundation of advanced PCa treatment. The homeostatic process of bone remodeling - produced by concerted actions of bone-building osteoblasts, bone-resorbing osteoclasts, and regulatory osteocytes - may also be subverted by PCa to promote metastatic growth. Mechanisms driving skeletal development and homeostasis, such as regional hypoxia or matrix-embedded growth factors, may be subjugated by bone metastatic PCa. In this way, the biology that sustains bone is integrated into adaptive mechanisms for the growth and survival of PCa in bone. Skeletally metastatic PCa is difficult to investigate due to the entwined nature of bone biology and cancer biology. Herein, we survey PCa from origin, presentation, and clinical treatment to bone composition and structure and molecular mediators of PCa metastasis to bone. Our intent is to quickly yet effectively reduce barriers to team science across multiple disciplines that focuses on PCa and metastatic bone disease. We also introduce concepts of tissue engineering as a novel perspective to model, capture, and study complex cancer-microenvironment interactions.

Regenerative medicine endeavors to restore damaged tissues and organs utilizing biological approaches. Utilizing biomaterials to target and regulate the pathophysiological processes of injured tissues stands as a crucial method in propelling this field forward. The Extracellular Vesicles-in-Hydrogel (EViH) system amalgamates the advantages of extracellular vesicles (EVs) and hydrogels, rendering it a prominent biomaterial in regenerative medicine with substantial potential for clinical translation. This review elucidates the development and benefits of the EViH system in tissue regeneration, emphasizing the interaction and impact of EVs and hydrogels. Furthermore, it succinctly outlines the pathophysiological characteristics of various types of tissue injuries such as wounds, bone and cartilage injuries, cardiovascular diseases, nerve injuries, as well as liver and kidney injuries, underscoring how EViH systems target these processes to address related tissue damage. Lastly, it explores the challenges and prospects in further advancing EViH-based tissue regeneration, aiming to impart a comprehensive understanding of EViH. The objective is to furnish a thorough overview of EViH in enhancing regenerative medicine applications and to inspire researchers to devise innovative tissue engineering materials for regenerative medicine.

Digital light processing (DLP)-based bioprinting technology holds immense promise for the advancement of hydrogel constructs in biomedical applications. However, creating high-performance hydrogel constructs with this method is still a challenge, as it requires balancing the physicochemical properties of the matrix while also retaining the cellular activity of the encapsulated cells. Herein, we propose a facile and practical strategy for the 3D bioprinting of high-performance hydrogel constructs through the in-situ birth of stem cell spheroids. The strategy is achieved by loading the cell/dextran microdroplets within gelatin methacryloyl (GelMA) emulsion, where dextran functions as a decoy to capture and aggregate the cells for bioprinting while GelMA enables the mechanical support without losing the structural complexity and fidelity. Post-bioprinting, the leaching of dextran results in a smooth curved surface that promotes in-situ birth of spheroids within hydrogel constructs. This process significant enhances differentiation potential of encapsulated stem cells. As a proof-of-concept, we encapsulate dental pulp stem cells (DPSCs) within hydrogel constructs, showcasing their regenerative capabilities in dentin and neovascular-like structures in vivo. The strategy in our study enables high-performance hydrogel tissue construct fabrication with DLP-based bioprinting, which is anticipated to pave a promising way for diverse biomedical applications.

This review paper explores the cutting-edge advancements in hydrogel design for articular cartilage regeneration (CR). Articular cartilage (AC) defects are a common occurrence worldwide that can lead to joint breakdown at a later stage of the disease, necessitating immediate intervention to prevent progressive degeneration of cartilage. Decades of research into the biomedical applications of hydrogels have revealed their tremendous potential, particularly in soft tissue engineering, including CR. Hydrogels are highly tunable and can be designed to meet the key criteria needed for a template in CR. This paper aims to identify those criteria, including the hydrogel components, mechanical properties, biodegradability, structural design, and integration capability with the adjacent native tissue and delves into the benefits that CR can obtain through appropriate design. Stratified-structural hydrogels that emulate the native cartilage structure, as well as the impact of environmental stimuli on the regeneration outcome, have also been discussed. By examining recent advances and emerging techniques, this paper offers valuable insights into developing effective hydrogel-based therapies for AC repair.

A substantial amount of funds are devoted to developing new biomaterials for the anterior cruciate ligament (ACL) each year. Over the past few decades, significant progress has been made in ACL tissue engineering. Successful tissue engineering approaches should be able to replicate native ACLs, necessitating a comprehensive understanding of biomaterials and biological responses. Various natural and synthetic biomaterials and their combinations have been investigated to create innovative scaffold systems for ACL regeneration. The next generation biomaterials should have a proper balance between mechanical properties and cell response. Recent advancements in ACL biomaterials, while promising, still face certain limitations that hinder their utilization in the human body. This review aims to explore recent biomaterials and their characteristics in the context of ACL tissue engineering. Starting with an overview of native ACL properties, we delve into different types of biomaterials, including natural, synthetic, and nanoparticles utilized in ACL tissue engineering. For each biomaterial, we discuss the biological response and highlight the challenges and future directions in developing innovative biomaterials for ACL repair and replacement scaffolds.

This literature review rigorously examines the growing scientific interest in computational methods for Tissue Engineering and Regenerative Medicine biofabrication, a leading-edge area in biomedical innovation, emphasizing the need for accurate, multi-stage, and multi-component biofabrication process models. The paper presents a comprehensive bibliometric and contextual analysis, followed by a literature review, to shed light on the vast potential of computational methods in this domain. It reveals that most existing methods focus on single biofabrication process stages and components, and there is a significant gap in approaches that utilize accurate models encompassing both biological and technological aspects. This analysis underscores the indispensable role of these methods in understanding and effectively manipulating complex biological systems and the necessity for developing computational methods that span multiple stages and components. The review concludes that such comprehensive computational methods are essential for developing innovative and efficient Tissue Engineering and Regenerative Medicine biofabrication solutions, driving forward advancements in this dynamic and evolving field.

Regarded as the most promising treatment modality for retinal degenerative diseases, retinal pigment epithelium cell replacement therapy holds significant potential. Common retinal degenerative diseases, including Age-related Macular Degeneration, are frequently characterized by damage to the unit comprising photoreceptors, retinal pigment epithelium, and Bruch's membrane. The selection of appropriate tissue engineering materials, in conjunction with retinal pigment epithelial cells, for graft preparation, can offer an effective treatment for retinal degenerative diseases. This article presents an overview of the research conducted on retinal pigment epithelial cell tissue engineering, outlining the challenges and future prospects.

ABSTRACT: Electrospinning is a simple and versatile technique that uses electrostatic forces to create fibers in the nano to micro range from a variety of materials, both synthetic and natural. Due to the high surface area to volume ratio, high porosity, and desirable mechanic characteristics of electrospun fibers, they are of current interest for a wide variety of applications. Some of the most significant applications of these fibers being researched include tissue engineering, drug delivery, wound dressings, environmental and energy applications, and protective materials. Notably, electrospun fibers may be specially tailored to better fit their final application through the direct loading of materials during the spinning process as well as by choosing the correct base material for the fiber. For example, it is desirable to use a biocompatible and biodegradable material in fibers desired for applications in the biomedical field; this way the fibers are able to safely interact with the human body. This review will explore the applications, as previously listed, with a focus on how fibers are made using carbohydrate polymers (such as alginate, cellulose and its derivatives, chitosan and chitin, starch, pullulan, hyaluronic acid, dextran, and levan) as their base material, and their applicability and functionality in various applications.

BACKGROUND: Scholars at home and abroad consider New Zealand rabbits to be an ideal model animal because of the similar anatomical morphology of the lumbar spine to that of the human lumbar spine. There is a lack of systematic comparison of different ways to establish rabbit intervertebral disc degeneration models under X-ray guidance. OBJECTIVE: To establish a rabbit model of lumbar disc degeneration using X-ray guided acupuncture, end-plate injection and combined method, and to compare the modeling effects of these three methods. METHODS: Eighteen 6-month-old New Zealand white rabbits were randomly selected and divided into four groups: acupuncture group, endplate injection group, combined group and blank control group. In the acupuncture group, three consecutive segments of the intervertebral discs (L2/3, L3/4, L4/5) were needled and modeled; in the endplate injection group, 50 μL of anhydrous ethanol was injected at a single point on the endplates of the three consecutive segmental discs; in the combined group, three consecutive segmental intervertebral discs were needled and injected with 50 μL of anhydrous ethanol at four azimuthal points on the endplates of the corresponding segmental discs; and the blank control group received no interventions. X-ray examination was performed to measure the disc height index at 2, 4, and 8 weeks after surgery. The intervertebral disc tissues were then taken for anatomical observation and pathological examination. RESULTS AND CONCLUSION: (1) Anatomical examination showed that fibrous annulus rupture, nucleus pulposus degeneration, and total disc structure disorder were the main manifestation in the acupuncture group, endplate injection group, and combined group, respectively. (2) X-ray examination showed that the disc height index showed the most obvious reduction in the acupuncture group at 2 weeks after operation, significant reductions in the endplate injection group at 2 and 4 weeks after operation, and significant reductions in the combined group at 2, 4, and 8 weeks after operation. (3) Pathological examination showed that the fibrous ring structure was damaged and the inner annulus fibrosus protruded inward in the acupuncture group; endplate fissure, disordered arrangement and nucleus loss were observed in the endplate injection group; total disc structure disorder with the nucleus pulposus losing water and shrinking and no obvious border with the broken annulus fibrosus was found in the combined group. To conclude, acupuncture, endplate injection and the modified endplate injection method can establish the rabbit intervertebral disc degeneration model. Compared with the single method, the modified endplate injection method can greatly accelerate and aggravate the degeneration of the intervertebral disc, and can effectively shorten the experiment period. [ABSTRACT FROM AUTHOR]

BACKGROUND: The regulation of M1/M2 polarization direction of macrophages is particularly critical in tissue engineering applications, and timely regulation can minimize proinflammatory, anti-inflammatory, or tissue healing responses. OBJECTIVE: To implant lentivirus-mediated miRNA-378a macrophage strain complex collagen to detect the expression level of immune regulation in the in vivo environment, and further clarify the influence of miRNA-378a in promoting macrophage M2 polarization in immune regulation and tissue repair in the in vivo environment. METHODS: Lentivirus-mediated miRNA-378a overexpressing macrophage cell lines and negative control virus macrophage lines were amplified and screened, and the macrophage lines were recovered and cultured together with collagen sponge to form a composite scaffold, which was divided into the following groups: (1) Positive group: miRNA-378a overexpressing macrophage-collagen sponge composite; (2) negative group: negative control of virus-mediated miRNA-378a macrophage-collagen sponge composite; (3) control group: macrophage-collagen sponge; (4) blank control group: collagen sponge. The cell density, phenotype, and adhesion of each group were observed by immunofluorescence and scanning electron microscopy. The cells were implanted into the subcutaneous model of the back of mice, and the mice were sacrificed 4 and 7 days after modeling. The direction of macrophage polarization in the collagen sponge composite of macrophages with miRNA-378a overexpression mediated by lentivirus and its effect on immune regulation and tissue repair were analyzed by gross observation, hematoxylin-eosin staining, MASSON staining, and immunohistochemistry. RESULTS AND CONCLUSION: (1) Under immunofluorescence microscopy, the macrophage cell lines in each group were observed to form a composite scaffold with the collagen sponge. (2) Under scanning electron microscope, lentivirus-mediated miRNA-378a macrophages in the positive group proliferated in cell density, had spherical, elliptic and polygonal differentiation, and had more pseudofeet than other groups. (3) Under general observation, the overall 7-day healing was better than that at 4 days. Lentivirus-mediated miRNA-378a macrophages in the positive group healed better than other groups regardless of 4 and 7 days. (4) Lentivirus-mediated miRNA-378a macrophages in the positive group under hematoxylin-eosin staining and MASSON staining had more amounts of fibrocytes, capillaries, fibroblasts, and collagen fiber hyperplasia. (5) Immunohistochemistry showed that lentivirus-mediated miRNA-378a macrophages in the positive group were more positive in 4- and 7-day M2 polarized cells than in other groups. The macrophages of the control and negative groups in 4- and 7-day M2 polarized cells were greater than that of the blank control group. There was no statistical difference between the control group and the negative group. The number of stained cells in the positive, negative, and control groups regardless of 4 and 7 days was higher than that in the blank control group, and the positive group > negative group ≈ control group > blank control group. (6) It is concluded that macrophages with miRNA-378a overexpression have a large amount of fibroblasts, capillaries, fibroblasts, and collagen fiber hyperplasia in vivo, which has a positive effect on tissue repair, and can promote the polarization of macrophages towards M2 type and inhibit the polarization of M1 type, thus contributing to reducing the inflammatory response of the body. [ABSTRACT FROM AUTHOR]

BACKGROUND: Research on carbon nanomaterials in the biomedical field is booming, and related scientific research results are increasing year by year. However, visualization analysis of the annual number of publications, the research status of countries, institutions, authors, and research hotspots and trends in this field is relatively scarce. OBJECTIVE: To present the research status of carbon nanomaterials in biomedical field, reveal the main research subjects, explore the research hotspots and development trends, and provide a reference for the future development of this field. METHODS: The core data set of Web of Science was used as the literature source to search the relevant researches on carbon nanomaterials in the biomedical field from 2012 to 2023. The knowledge map was generated by using Citespace software with countries, institutions, authors, keywords, and co-citations as nodes and for visualization analysis. RESULTS AND CONCLUSION: (1) A total of 2 932 papers were included in this study. In the medical field, carbon nanomaterials had a large number of papers and a fast growth rate. The United States has a large number of papers; China is an emerging force in this field, although the number of papers is the largest, but the level of research and influence need to be improved. The Chinese Academy of Sciences is the largest cooperative network institution, which mainly targets domestic institutions and lacks cooperation with well-known foreign institutions. (2) Keyword analysis displays that the green synthesis method and application of displaying carbon points have been the focus of research, followed by the new method of combining carbon nanomaterials with cancer phototherapy and immunotherapy, the key direction of future research. (3) The dynamic development trend of co-citations suggests that tissue engineering is a hot research topic of carbon nanomaterials in the field of biomedicine, mainly including the research of carbon nanomaterials for the repair and regeneration of heart and nerve tissue and as a bio-ink additive for 3D and 4D bioprinting. (4) In the future, with the development of the biomedical field in the direction of precision and treatment, researchers should speed up the creation of carbon-based systems formed by the combination of scientific and effective carbon nanomaterials with science and technology, new polymers or organic molecules, and new therapeutic methods, so as to give full play to the maximum effect of carbon nanomaterials. [ABSTRACT FROM AUTHOR]

BACKGROUND: Polylactic acid (PLA) has good biocompatibility and a controllable degradation rate and is currently widely used in biomedical engineering. However, PLA has shortcomings such as low mechanical strength and insufficient biological activity, which limits its further application in bone tissue engineering. OBJECTIVE: To construct polylactic acid/polydopamine/tantalum (PLA/PDA/Ta) bone tissue engineering scaffolds, and explore their biosafety and in vitro osteogenesis. METHODS: A PLA scaffold with a porous structure was prepared through liquid crystal display light-curing technology. PLA/PDA scaffolds and PLA/PDA/Ta scaffolds were prepared by soaking PLA scaffolds in dopamine solution and dopamine-tantalum nanoparticle solution, respectively. The microstructure and water contact angle of scaffolds were characterized. MC3T3-E1 cells were co-cultured with PLA, PLA/PDA, and PLA/PDA/Ta scaffolds, respectively, and CCK-8 assay and live/dead cell staining were performed. After osteogenic differentiation, alkaline phosphatase, alizarin red staining, and osteogenic gene detection were performed. RESULTS AND CONCLUSION: (1) The scanning electron microscope results exhibited that the three kinds of prepared scaffolds had an interconnected porous three-dimensional structure, and the average pore diameter was 200 μm. The water contact angle of PLA/PDA/Ta scaffolds was lower than that of PLA and PLA/ PDA scaffolds (P < 0.05). (2) CCK-8 assay showed that compared with PLA and PLA/PDA scaffolds, PLA/PDA/Ta scaffolds could promote cell proliferation (P < 0.05). Live/dead cell staining showed good cell proliferation in the three groups. (3) Alkaline phosphatase and alizarin red staining showed that compared with PLA and PLA/PDA scaffolds, PLA/PDA/Ta scaffolds could promote the expression of alkaline phosphatase and the formation of mineralized nodules. RT-qPCR showed that compared with PLA and PLA/PDA scaffolds, PLA/PDA/Ta scaffolds could enhance the mRNA expression of cell bone morphogenetic protein, Runx- 2, and type I collagen (P < 0.05, P < 0.01). (4) The results showed that the PLA/PDA/Ta scaffold had excellent osteogenic activity and the ability to promote cell proliferation. [ABSTRACT FROM AUTHOR]

Biomaterial-based implantable scaffolds capable of promoting physical and functional reconnection of injured spinal cord and nerves represent the latest frontier in neural tissue engineering. Here, we report the fabrication and characterization of self-standing, biocompatible and bioresorbable substrates endowed with both controlled nanotopography and electroactivity, intended for the design of transient implantable scaffolds for neural tissue engineering. In particular, we obtain conductive and nano-modulated poly(D,L-lactic acid) (PLA) and poly(lactic- co -glycolic acid) free-standing films by simply iterating a replica moulding process and coating the polymer with a thin layer of poly(3,4-ethylendioxythiophene) polystyrene sulfonate. The capability of the substrates to retain both surface patterning and electrical properties when exposed to a liquid environment has been evaluated by atomic force microscopy, electrochemical impedance spectroscopy and thermal characterizations. In particular, we show that PLA-based films maintain their surface nano-modulation for up to three weeks of exposure to a liquid environment, a time sufficient for promoting axonal anisotropic sprouting and growth during neuronal cell differentiation. In conclusion, the developed substrates represent a novel and easily-tunable platform to design bioresorbable implantable devices featuring both topographic and electrical cues. [ABSTRACT FROM AUTHOR]

[Display omitted] Cartilage is severely limited in self-repair after damage, and tissue engineering scaffold transplantation is considered the most promising strategy for cartilage regeneration. However, scaffolds without cells and growth factors, which can effectively avoid long cell culture times, high risk of infection, and susceptibility to contamination, remain scarce. Hence, we developed a cell- and growth factor-dual free hierarchically structured nanofibrous sponge to mimic the extracellular matrix, in which the encapsulated core–shell nanofibers served both as mechanical supports and as long-lasting carriers for bioactive biomass molecules (glucosamine sulfate). Under the protection of the nanofibers in this designed sponge, glucosamine sulfate could be released continuously for at least 30 days, which significantly accelerated the repair of cartilage tissue in a rat cartilage defect model. Moreover, the nanofibrous sponge based on carboxymethyl chitosan as the framework could effectively fill irregular cartilage defects, adapt to the dynamic changes during cartilage movement, and maintain almost 100 % elasticity even after multiple compression cycles. This strategy, which combines fiber freeze-shaping technology with a controlled-release method for encapsulating bioactivity, allows for the assembly of porous bionic scaffolds with hierarchical nanofiber structure, providing a novel and safe approach to tissue repair. [ABSTRACT FROM AUTHOR]

Decellularized grafts have shown promising results in tissue engineering. The aim of decellularization is to create a scaffold that is devoid of immunogenic components, has natural tissue architecture, and can provide cellularity again. The aim of our study is to obtain a living/regenerative valve by coculture of HUVEC and human dermal fibroblast cells on the pulmonary heart valves of decellularized young sheep and subsequently perform their in vitro characterization to determine its suitability for clinical studies. Various characterization tests were applied to sheep pulmonary heart valves decellularized by the detergent-based method. HUVEC and dermal fibroblast cells were seeded on the scaffold, and their viability was determined by MTT analysis, adhesion by SEM, and cell infiltration by histological staining. Finally, to determine the regenerative ability of the resulting live cap, collagen type I (Col1), collagen type III (Col3), and elastin (Eln) gene expressions were analyzed by PCR. The results showed that cell proliferation increased day by day on the scaffold. In histological findings, it was observed that cellular regeneration was almost completely achieved, especially in arterial wall samples. According to PCR findings, a significant increase in Col1, Col3, and Eln gene expressions was observed in arterial wall samples. In this study, for the first time in the literature, the regeneration potential of differentiated human cells on decellularized sheep heart valves was observed, and markers related to new ECM production were analyzed. In conclusion, we suggest that the decellularized heart valves of young sheep can be used as a starting matrix in tissue engineering studies, and clinical studies are needed. [ABSTRACT FROM AUTHOR]

BACKGROUND: The in vitro construction of intestinal smooth muscle layer, as an important component of the intestinal wall, has attracted much attention in the bionic construction of tissue-engineered intestinal canal. OBJECTIVE: To explore the effects of cyclic mechanical stretching on the growth activity of intestinal smooth muscle cells and the expression of functional genes within collagen strips. METHODS: The collagen band culture system of intestinal smooth muscle cells was constructed using a self-designed collagen strip stretching culture device with self-made rat tail collagen as a scaffold and primary rat intestinal smooth muscle cells as seed cells. EthD-1/Calcein-AM cell activity staining, magenta staining, cytoskeleton-Ki67 immunofluorescence staining were used to observe the growth activity and proliferation of the cells, and quantitative RT-PCR was used to detect the expression of desmin, α-sma, and vimentin functional genes. RESULTS AND CONCLUSION: The collagen band culture system of intestinal smooth muscle cells was successfully constructed, and intestinal smooth muscle cells in the band had good cell activity. The number of Ki67 positive cells increased and desmin, α-sma and vimentin were significantly overexpressed under cyclic stretching and dynamic culture conditions (P < 0.001). To conclude, mechanical stimulation is beneficial to maintain the growth phenotype of smooth muscle cells and promote their functional differentiation during three-dimensional culture in vitro. [ABSTRACT FROM AUTHOR]

BACKGROUND: The etiology of osteoarthritis is varied and its pathogenesis is still unclear. As bioinformatics has been deepening in recent years, increasing studies have found that the aberrant expression of long non-coding RNAs (lncRNAs) and microRNAs (miRNAs) in joint tissues may mediate the downstream signaling pathways involved in the development of osteoarthritis. OBJECTIVE: To review the mechanism of lncRNA in the development of osteoarthritis and the therapeutic effects of monomers and active compounds derived from traditional Chinese medicine that modulate lncRNA and downstream signaling pathways in osteoarthritis. METHODS: We searched CNKI, WanFang, VIP, and PubMed using the search terms of “long non-coding RNA, knee osteoarthritis, miRNA, chondrocytes, signaling pathway, and traditional Chinese medicine” in Chinese and English, respectively. The search time was from the inception of each database to March 2023. A total of 61 articles were included according to the inclusion and exclusion criteria. RESULTS AND CONCLUSION: The pathogenesis of knee osteoarthritis involves a complex molecular regulatory network, including aberrant expression of lncRNAs and miRNAs in cartilage tissues, which may lead to apoptosis of chondrocytes, degradation of cartilage extracellular matrix, and production of large amounts of pro-inflammatory cytokines. These changes interact with each other to cause degeneration of articular cartilage and progression of osteoarthritis. Therefore, further in-depth studies are needed to reveal the fine mechanisms of the molecular regulatory network. The mechanism of traditional Chinese medicine in the treatment of osteoarthritis mainly focuses on regulating the expression of lncRNA and miRNA, thereby alleviating chondrocyte apoptosis and extracellular matrix degradation, promoting cell proliferation, and slowing down the development of osteoarthritis. [ABSTRACT FROM AUTHOR]

Acoustic manipulation or perturbation of biological soft matter has emerged as a promising clinical treatment for a number of applications within regenerative medicine, ranging from bone fracture repair to neuromodulation. The potential of ultrasound (US) endures in imparting mechanical stimuli that are able to trigger a cascade of molecular signals within unscathed cells. Particularly, low-intensity pulsed ultrasound (LIPUS) has been associated with bio-effects such as activation of specific cellular pathways and alteration of cell morphology and gene expression, the extent of which can be modulated by fine tuning of LIPUS parameters including intensity, frequency and exposure time. Although the molecular mechanisms underlying LIPUS are not yet fully elucidated, a number of studies clearly define the modulation of specific ultrasonic parameters as a means to guide the differentiation of a specific set of stem cells towards adult and fully differentiated cell types. Herein, we outline the applications of LIPUS in regenerative medicine and the in vivo and in vitro studies that have confirmed the unbounded clinical potential of this platform. We highlight the latest developments aimed at investigating the physical and biological mechanisms of action of LIPUS, outlining the most recent efforts in using this technology to aid tissue engineering strategies for repairing tissue or modelling specific diseases. Ultimately, we detail tissue-specific applications harnessing LIPUS stimuli, offering insights over the engineering of new constructs and therapeutic modalities. Overall, we aim to lay the foundation for a deeper understanding of the mechanisms governing LIPUS-based therapy, to inform the development of safer and more effective tissue regeneration strategies in the field of regenerative medicine. [ABSTRACT FROM AUTHOR]

Bone tissue engineering (BTE) applications and regenerative strategies have been used to improve the clinical practice of repairing large bone defects associated with surgical resections, congenital malformations, and trauma. The scaffolds are designed to stimulate a biological response, including cell interactions, and guide tissue regeneration by functioning as artificial biomimetic extracellular matrixes. Polymeric biomaterials are suitable for bone tissue engineering since they possess both chemical and physical properties, enabling the control of shape, morphology, and biodegradability, which makes them suitable for bone regeneration and tissue engineering applications. In vivo animal models were studied for collagen, chitosan, poly (lactic acid) (PLA) and high density polyethylene (HDPE), the four most common polymers employed in bone tissue engineering. Through analysis of the results of this review, the in vivo studies can provide a large-scale evaluation of the possibility of achieving optimal bone-forming capabilities and regenerative capabilities. Furthermore, the review will serve as an essential reference for bone tissue engineering applications as well as contribute to the development of novel in vivo investigations [ABSTRACT FROM AUTHOR]

Fabrication of engineered thin membranous tissues (TMTs) presents a significant challenge to researchers, as these structures are small in scale, but present complex anatomies containing multiple stratified cell layers. While numerous methodologies exist to fabricate such tissues, many are limited by poor mechanical properties, need for post‐fabrication, or lack of cytocompatibility. Extrusion bioprinting can address these issues, but lacks the resolution necessary to generate biomimetic, microscale TMT structures. Therefore, our goal was to develop a strategy that enhances bioprinting resolution below its traditional limit of 150 μm and delivers a viable cell population. We have generated a system to effectively shrink printed gels via electrostatic interactions between anionic and cationic polymers. Base hydrogels are composed of gelatin methacrylate type A (cationic), or B (anionic) treated with anionic alginate, and cationic poly‐L‐lysine, respectively. Through a complex coacervation‐like mechanism, the charges attract, causing compaction of the base GelMA network, leading to reduced sample dimensions. In this work, we evaluate the role of both base hydrogel and shrinking polymer charge on effective print resolution and cell viability. The alginate anion‐mediated system demonstrated the ability to reach bioprinting resolutions of 70 μm, while maintaining a viable cell population. To our knowledge, this is the first study that has produced such significant enhancement in extrusion bioprinting capabilities, while also remaining cytocompatible. [ABSTRACT FROM AUTHOR]

The objective of this study was to create injectable photo‐crosslinkable biomaterials, using gelatin methacryloyl (GelMA) hydrogel, combined with a decellularized bone matrix (BMdc) and a deproteinized (BMdp) bovine bone matrix. These were intended to serve as bioactive scaffolds for dentin regeneration. The parameters for GelMA hydrogel fabrication were initially selected, followed by the incorporation of BMdc and BMdp at a 1% (w/v) ratio. Nano‐hydroxyapatite (nHA) was also included as a control. A physicochemical characterization was conducted, with FTIR analysis indicating that the mineral phase was complexed with GelMA, and BMdc was chemically bonded to the amide groups of gelatin. The porous structure was preserved post‐BMdc incorporation, with bone particles incorporated alongside the pores. Conversely, the mineral phase was situated inside the pore opening, affecting the degree of porosity. The mineral phase did not modify the degradability of GelMA, even under conditions of type I collagenase‐mediated enzymatic challenge, allowing hydrogel injection and increased mechanical strength. Subsequently, human dental pulp cells (HDPCs) were seeded onto the hydrogels. The cells remained viable and proliferative, irrespective of the GelMA composition. All mineral phases resulted in a significant increase in alkaline phosphatase activity and mineralized matrix deposition. However, GelMA‐BMdc exhibited higher cell expression values, significantly surpassing those of all other formulations. In conclusion, our results showed that GelMA‐BMdc produced a porous and stable hydrogel, capable of enhancing odontoblastic differentiation and mineral deposition when in contact with HDPCs, thereby showing potential for dentin regeneration. [ABSTRACT FROM AUTHOR]

Corneal blindness affects over 10 million patients worldwide. Due to the limited supply of donor corneas and frequent graft failure, bioengineered alternatives are crucial. To overcome drawbacks associated with corneal substitutes from synthetic biomaterials, fabrication from plant‐derived biomaterials is a potential alternative. Herein, soy protein and glutenin in combination with different crosslinkers were evaluated for fabrication of corneal substitutes. Optical, mechanical, and biochemical properties of fabricated constructs and control rabbit corneas were evaluated in vitro. Soy protein crosslinked with peroxidase/H202 possessed transparency and mechanical properties comparable to controls, although their water content and biocompatibility were inferior. In contrast, soy protein crosslinked with tannic acid showed similar water content, tensile strength, and biocompatibility as rabbit corneas; however, these constructs displayed significantly lower transparency and higher strain to failure. Finally, glutenin cross‐linked using formaldehyde showed excellent transparency, strain to failure, and biocompatibility, however; they exhibited significantly lower water content and tensile strength than controls. This study is the first to establish CIELAB color values for the rabbit cornea, allowing quantitative optical evaluation of tissue‐engineered substitutes. Thus, a crosslinking strategy utilizing plant‐derived proteins for fabrication of constructs with properties comparable to rabbit corneas is a promising direction for development of tissue‐engineered corneal substitutes. [ABSTRACT FROM AUTHOR]

Augmentation of the nasal dorsum often requires implantation of structural material. Existing methods include autologous, cadaveric or alloplastic materials and injectable hydrogels. Each of these options is associated with considerable limitations. There is an ongoing need for precise and versatile implants that produce long‐lasting craniofacial augmentation. Four separate polylactic acid (PLA) dorsal nasal implant designs were 3D‐printed. Two implants had internal PLA rebar of differing porosities and two were designed as "shells" of differing porosities. Shell designs were implanted without infill or with either minced or zested processed decellularized ovine cartilage infill to serve as a "biologic rebar", yielding eight total treatment groups. Scaffolds were implanted heterotopically on rat dorsa (N = 4 implants per rat) for explant after 3, 6, and 12 months followed by volumetric, histopathologic, and biomechanical analysis. Low porosity implants with either minced cartilage or PLA rebar infill had superior volume retention across all timepoints. Overall, histopathologic and immunohistochemical analysis showed a resolving inflammatory response with an M1/M2 ratio consistently favoring tissue regeneration over the study course. However, xenograft cartilage showed areas of degradation and pro‐inflammatory infiltrate contributing to volume and contour loss over time. Biomechanical analysis revealed all constructs had equilibrium and instantaneous moduli higher than human septal cartilage controls. Biocompatible, degradable polymer implants can induce healthy neotissue ingrowth resulting in guided soft tissue augmentation and offer a simple, customizable and clinically‐translatable alternative to existing craniofacial soft tissue augmentation materials. PLA‐only implants may be superior to combination PLA and xenograft implants due to contour irregularities associated with cartilage degradation. [ABSTRACT FROM AUTHOR]

Abstract The human mammary gland represents a highly organized and dynamic tissue, uniquely characterized by postnatal developmental cycles. During pregnancy and lactation, it undergoes extensive hormone-stimulated architectural remodeling, culminating in the formation of specialized structures for milk production to nourish offspring. Moreover, it carries significant health implications, due to the high prevalence of breast cancer. Therefore, gaining insight into the unique biology of the mammary gland can have implications for managing breast cancer and promoting the well-being of both women and infants. Tissue engineering techniques hold promise to narrow the translational gap between existing breast models and clinical outcomes. Here, we provide an overview of the current landscape of breast tissue engineering, outline key requirements, and the challenges to overcome for achieving more predictive human breast models. We propose methods to validate breast function and highlight preclinical applications for improved understanding and targeting of breast cancer. Beyond mammary gland physiology, representative human breast models can offer new insight into stem cell biology and developmental processes that could extend to other organs and clinical contexts.

Despite significant advances in the prevention, diagnosis, and treatment of cardiac diseases, this condition is still considered one of the major challenges facing the global healthcare system. According to the World Health Organization (WHO) statistics, cardiovascular diseases (CVD) are among the leading causes of mortality worldwide. It is predicted that in the future, due to population aging, urbanization, and lifestyle changes, the mortality rate from cardiac diseases will increase. Current pharmacological approaches only extend the lifespan of patients without providing cardiac tissue repair. In the advanced stages of these diseases, apart from heart transplantation, there is no curative treatment available. However, due to limited suitable donors and post-operative risks and complications such as graft rejection, primary graft failure, and common infections after heart transplant, transplantation is not always feasible. Stem cells have created a wide range of hope in the world since their discovery. With increased research on stem cells and cell therapy in recent decades, researchers have found that utilizing this innovative therapeutic approach can increase lifespan and improve patient outcomes. Various countries have invested millions of dollars in the application of stem cells for treating various diseases in recent years. Embryonic stem cells (ESCs) have great differentiation potential, but their medical application faces severe ethical and religious constraints. The identification of potent induced pluripotent stem cells has revolutionized regenerative medicine. These cells possess all the capabilities of embryonic stem cells and can easily differentiate into cardiac myocytes. Furthermore, the paracrine effects of induced pluripotent stem cells (iPSCs) and extracellular vesicles (EVs) secreted from these cells in regenerative medicine have garnered significant attention. Among extracellular secretory vesicles, researchers have focused more on exosomes. Exosomes are vesicles ranging from 30 to 100 nanometers that have a plasma membrane-like topology and can enter target cells and deliver their cargo. Cardiac patches are a novel achievement resulting from the integration of tissue engineering and cell sciences and are used to improve cardiac injuries. Cardiac patches consist of a natural or synthetic scaffold designed to support and restore myocardial tissue following injury, and they are implanted into the heart tissue. The primary approach to using cardiac patches is to provide physical support to damaged heart tissue. Nowadays, the combination of cardiomyocytes derived from potent induced pluripotent stem cells along with biocompatible materials and growth factors has created specialized cardiac patches capable of precise delivery of many cells and minimizing cellular damages in vivo conditions. This review article aims to explore the latest advances in cardiac regenerative medicine through the use of cardiac patches, induced pluripotent stem cells, and exosomes derived from them; as well as to assess the challenges ahead in cardiac regenerative medicine using the mentioned items to alleviate and improve tissue damage to the heart, and ultimately provide an overview of new perspectives for future research in cardiac regenerative medicine.

Tissue engineering and regenerative medicine (TERM) is an emerging field that has provided new therapeutic opportunities by delivering innovative solutions. The development of nontraditional therapies for previously unsolvable diseases and conditions has brought hope and excitement to countless individuals globally. Many regenerative medicine therapies have been developed and delivered to patients clinically. The technology platforms developed in regenerative medicine have been expanded to various medical areas; however, their applications in colorectal surgery remain limited. Applying TERM technologies to engineer biological tissue and organ substitutes may address the current therapeutic challenges and overcome some complications in colorectal surgery, such as inflammatory bowel diseases, short bowel syndrome, and diseases of motility and neuromuscular function. This review provides a comprehensive overview of TERM applications in colorectal surgery, highlighting the current state of the art, including preclinical and clinical studies, current challenges, and future perspectives. This article synthesizes the latest findings, providing a valuable resource for clinicians and researchers aiming to integrate TERM into colorectal surgical practice.

Abstract Large bone defects are a significant health problem today with various origins, including extensive trauma, tumours, or congenital musculoskeletal disorders. Tissue engineering, and in particular bone tissue engineering, aims to respond to this demand. As such, we propose a specific model based on Elastin-Like Recombinamers-based click-chemistry hydrogels given their high biocompatibility and their potent on bone regeneration effect conferred by different bioactive sequences. In this work we demonstrate, using biochemistry, histology, histomorphometry and imaging techniques, the biocompatibility of our matrix and its potent effect on bone regeneration in a model of bone parietal lesion in female New Zealand rabbits.

Abstract The nanoparticles (NPs) of metals and metal oxides constitute significant components of technology in terms of monometallic NPs (MNPs). Over the last decade, the most fascinating and in‐depth uses of NPs have been found in the biomedical field, which has demonstrated the therapeutic potential of these particles. Significant strides have been made in the application of nanotechnology across various industries, including biomedical sciences. In biomedicine, two of the most important applications of NPs are in the diagnosis and treatment of disease. Given their ability to deliver specific drugs, these next‐generation NPs provide safe and effective pharmacotherapies for a wide range of disorders. Selenium nanoparticles (SeNPs) and titanium dioxide (TiO2) NPs offer potential treatments for various applications, including hair care and cancer treatment. SeNPs help with abiotic stress, plant disease, and growth, while TiO2 NPs enhance bio‐imaging and drug delivery. This comprehensive review focuses on MNPs like Se (metal‐based) and TiO2 (metal‐oxide based). It covers their synthesis methods, nanoscale physicochemical properties, and the definition of specific industrial applications in various fields of applied nanotechnology, including biomedicine.

Objective To prepare composite scaffolds for rat H9C2 cardiomyocytes, and to optimize the scaffolds that facilitate the growth of H9C2 cardiomyocytes. Methods The electrospinning method was used to prepare three types of compo-site scaffolds, i.e., polycaprolactone (PCL)/chitosan (CS) scaffold (scaffold A), PCL/CS/zinc oxide (ZnO) scaffold (scaffold B), and PCL/CS/ZnO/carbon nanotubes (CNTs) scaffold (scaffold C), and the preparation of scaffolds was verified by the methods including X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, thermogravimetric (TG) analysis, and Raman spectroscopy. Electron microscopy and tensile stress, water contact angle, conductivity, and expansion rate tests were used to eva-luate the physical and chemical properties of the three types of scaffolds, and DAPI staining, electron microscopy, and CCK-8 assay were used to evaluate the biocompatibility of the three types of scaffolds. Results XRD, FTIR spectroscopy, TG analysis, and Raman spectroscopy showed that the three types of scaffolds were successfully prepared. Electron microscopy showed that scaffold C had a significantly longer fiber diameter than scaffold A (F=73.050,t=8.724,9.747,P

Abstract The demand for fish protein continues to increase and currently accounts for 17% of total animal protein consumption by humans. About 90% of marine fish stocks are fished at or above maximum sustainable levels, with aquaculture propagating as one of the fastest growing food sectors to address some of this demand. Cell-cultivated seafood production is an alternative approach to produce nutritionally-complete seafood products to meet the growing demand. This cellular aquaculture approach offers a sustainable, climate resilient and ethical biotechnological approach as an alternative to conventional fishing and fish farming. Additional benefits include reduced antibiotic use and the absence of mercury. Cell-cultivated seafood also provides options for the fortification of fish meat with healthier compositions, such as omega-3 fatty acids and other beneficial nutrients through scaffold, media or cell approaches. This review addresses the biomaterials, production processes, tissue engineering approaches, processing, quality, safety, regulatory, and social aspects of cell-cultivated seafood, encompassing where we are today, as well as the road ahead. The goal is to provide a roadmap for the science and technology required to bring cellular aquaculture forward as a mainstream food source.

Introduction: Physical factors like stiffness and surface features are among the characteristics that affect the performance of barrier membranes and determine the results of regenerative processes. A perfect equilibrium between the membrane’s rigidity and mechanical stability guarantees effective periodontal regeneration. The study’s novelty lies in comparing the physical characteristics, namely morphology, tensile strength, wettability, and biological characteristics, namely biocompatibility and enzyme resistance properties, of the Fix-GideTM membrane against the gold standard membrane, Bio-Gide®. Aim: To explore the physical and biological properties of two commercially available barrier membranes in oral tissue regeneration. Materials and Methods: The present in-vitro study compared two commercially available membranes, namely Bio-Gide® and Fix-GideTM. Both membranes are bilayered resorbable membranes, with Bio-Gide composed of porcine dermis Type-I and III collagen and Fix-GideTM of bovine origin. The study was conducted at the Central Leather Research Institute, and the membranes were procured from Sri Ramachandra Institute of Higher Education and Research. Morphological characterisation was done using Scanning Electron Microscopy (SEM). Physical properties were evaluated using a tensile strength test, enzyme resistance test, and wettability measurement. Biocompatibility assessment was also performed. The Statistical Package for Social Sciences (SPSS) software was used to run the Mann-Whitney U test to analyse the statistical data obtained in the enzyme resistance test. Results: Biocompatibility assessment showed no cytotoxic profile of both membranes, portraying their biocompatible nature. Morphological analysis using SEM showed the surface of the Bio-Gide® membrane to be considerably smoother than the Fix-GideTM membrane. Both membranes, however, have fibrous and porous features on their inner surfaces. Tensile strength assessment found that the percentage of elongation was better with Bio-Gide (1.7±0.4 and 4.8±0.4) when compared to Fix-Gide (15.8±0.2 and 2.2±0.2) in both wet and dry states, respectively. The enzyme resistance test evaluated in dry and wet settings showed that the membranes, namely, Bio-Gide® membrane exhibited around 29±2% of degradation, whereas the Fix-GideTM exhibited only 18±2%. These mechanical profiles exhibited that the membranes has appreciable differences, although there wasn’t a statistically significant difference between them (p=0.68). According to wettability studies, Bio-Gide is hydrophilic, but Fix-GideTM is hydrophobic. Conclusion: The observations of the present study showed that Fix-Gide had comparable physio-biological properties to that of the Bio-Gide membrane. This supports the suitability of the use of both membranes for various oral tissue regeneration procedures.

Approximately 740 million symptomatic patients are affected by otitis media every year. Being an inflammatory disease affecting the middle ear, it is one of the primary causes of tympanic membrane (TM) perforations, often resulting in impaired hearing abilities. Antibiotic therapy using broad-spectrum fluoroquinolones, such as ciprofloxacin (CIP), is frequently employed and considered the optimal route to treat otitis media. However, patients often get exposed to high dosages to compensate for the low drug concentration reaching the affected site. Therefore, this study aims to integrate tissue engineering with drug delivery strategies to create biomimetic scaffolds promoting TM regeneration while facilitating a localized release of CIP. Distinct electrospinning (ES) modalities were designed in this regard either by blending CIP into the polymer ES solution or by incorporating nanoparticles-based co-ES/electrospraying. The combination of these modalities was investigated as well. A broad range of release kinetic profiles was achieved from the fabricated scaffolds, thereby offering a wide spectrum of antibiotic concentrations that could serve patients with diverse therapeutic needs. Furthermore, the incorporation of CIP into the TM patches demonstrated a favorable influence on their resultant mechanical properties. Biological studies performed with human mesenchymal stromal cells confirmed the absence of any cytotoxic or anti-proliferative effects from the released antibiotic. Finally, antibacterial assays validated the efficacy of CIP-loaded scaffolds in suppressing bacterial infections, highlighting their promising relevance for TM applications.