Abstract Bioprosthetic valves are employed to replace defective heart valves. However, structural degeneration is prevalent in bioprosthetic valves because the heart valve leaflets are exposed to ...extreme and repetitive cardiovascular pressure. Herein, a silk fibroin‐based heart valve leaflet, which executes the physiological role of a heart valve, is developed. To this end, a templated assembly technology is developed. Notably, a physically optimal hierarchical structure for replacing the natural heart valve leaflet is realized by numerous firmly stacked β‐sheet crystals distributed within collective tyrosine‐reinforcing amorphous strands. Almost half (46.9%) of the silk fibroin‐based heart valve leaflet comprises strongly stacked β‐sheet crystals, leading to a 292% enhancement in stacking strength. The templated assembly results in the entanglement of amorphous strands, upregulating the non‐covalent interactions within the tyrosine. Consequently, the strength is enhanced by 1380% compared to native silk fibroin. Moreover, the templated assembly enhances the static and dynamic mechanical properties, thereby delivering a desirable performance for its use in heart valve replacement. Interestingly, the aortic valve composed of silk fibroin‐based leaflets does not fail under the cardiovascular pressure of 60–180 mmHg. Furthermore, the valve performance is satisfactory and surmounts the requirements of the industrial standard ISO 5840.
In nature, water is vital for maintaining homeostasis. Particularly, organisms (e.g., plant leaf, bird feather) exploit water fluidics for motions. Hydration-adaptive crystallization is the ...representative water-responsive actuation of biopolymers. This crystallization has inspired the development of intelligent human–robot interfaces. At the same time, it hinders the consistent adhesion of tissue adhesive. As hydration-adaptive crystallization is inevitable, the on-demand control of crystallization is desirable in the innovative biopolymeric biomedical systems. To this end, this study developed an amino acid-based technology to artificially up- or down-regulate the inevitable crystallization of silk fibroin. A case II diffusion model was constructed, and it revealed that the activity of polar amino acid is related to crystallization kinetics. Furthermore, the water dynamics study suggested that active amino acid stabilizes crystallization-triggering water molecules. As a proof-of-concept, we verified that a 30% increase in the activity of serine resulted in a 50% decrease in the crystallization rate. Furthermore, the active amino acid-based suppression of hydration-adaptive crystallization enabled the silk fibroin to keep its robust adhesion (approximately 160 kJ m–3) by reducing the water-induced loss of adhesive force. The proposed silk fibroin was demonstrated as a stable tissue adhesive applied on ex vivo porcine mandible tissue. This amino acid-based regulation of hydration-adaptive crystallization will pioneer next-generation biopolymer-based healthcare.
Repair of critical-size bone defects (CBD) remains a challenge in orthopedic surgery due to the restricted regenerative capacity of bone tissue. Herein, multi-functional biphasic calcium phosphate ...(BCP) blocks decorated with gelatin packs were developed for bone regeneration of CBDs. The gelatin packs consist of gelatin microspheres (GMSs) and an enzymatic crosslinked gelatin layer for bone morphogenetic protein-2 (BMP-2) and antibiotics delivery. The porous interior of the BCP block was filled with GMSs containing BMP-2 and tightly packed with an enzymatic crosslinked gelatin layer. The outermost part of the block was then covered with antibiotics-loaded GMSs. The BCP platform elaborately decorated for each zone improved the adhesion of osteoblasts and enabled the sequential release of antibiotics and BMP-2 and sustained release of BMP-2, realizing on-demand drug release according to the treatment stage. The programmed drug release of this platform significantly improved the regeneration of CBDs. In vivo experiments using dog's mandible defect models clearly demonstrated the clinical application potential of this BCP platform.
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•A bone graft functionalized with gelatin packs was developed.•The gelatin pack consists of gelatin microspheres (GMSs) optimized for the delivery of antibiotics and BMP-2.•This platform achieved programmed dual drug release to enable a one-step treatment of critical-sized bone defects.•This platform minimized the initial postoperative swelling and promoted accelerated bone formation.
Owing to their superior hydrophilicity, zwitterionic molecules are known to form a strong hydration layer serving as an effective antifouling barrier. Despite their widespread use, the immobilization ...of zwitterionic molecules on various surfaces has posed a considerable challenge. Herein, we designed zwitterionic polyethers functionalized with mussel-inspired catechol moieties, which can be applied as versatile coatings with enhanced antifouling properties for biomedical surfaces. A series of block polyethers were synthesized
via
sequential anionic ring-opening polymerization of catechol-acetonide glycidyl ether and
N
,
N
-diisopropyl ethanolamine glycidyl ether, followed by post-polymerization modification to afford the desired zwitterionic brushes. The versatile surface adsorption and superior antifouling effects of the synthesized polyether brushes were evaluated using atomic force microscopy, quartz crystal microbalance with dissipation, and bioassay on the biomedical device surfaces. This study highlights the superior antifouling properties of zwitterionic polyether brushes, with potential applications in biomedical surfaces.
Zwitterionic polyether brushes bearing mussel-inspired catechol moieties are developed for versatile coatings with improved antifouling properties on biomedical surfaces.
Abstract
As the technologies for treating diseases are attracting continuous attention, physical therapy methods, particularly electrical stimulation (ES), have been widely investigated owing to ...their high effectiveness. As ES essentially requires an external power source, various efforts are being devoted to achieving the application of ES to the human body using nanogenerators. Various studies have verified the effect of ES by applying the same output generated by the device to in vitro and in vivo bio‐electrical stimulation. However, it is unknown whether the electrical output generated by the device can be transmitted equally in the cell unit, and this is considered a common missing link in bio‐electrical stimulation research. Herein, the missing link between electrical devices and in vitro bio‐electrical stimulations is unraveled by the ex vivo, 2D simulation, and in vitro study of body‐mediated energy transfer (BmET) models. In addition, BmET‐based ES is applied to pre‐osteoblasts, and the increased cellular functions are verified.
Abstract
Background and Objectives
Anecdotal evidence and references to boredom appear frequently in mass media, but only a few studies directly examine the phenomenon of boredom, and existing ...literature within the context of leisure has primarily focused on adolescents. Social isolation and loneliness often intertwine with boredom, and chronic conditions are major factors that increase the risk of experiencing boredom in later life. Therefore, the purpose of this paper is to examine the significance of boredom among older adults and assess the existing literature to gain a more holistic understanding of boredom and how it has been studied among older adults in the context of leisure.
Research Design and Methods
Following the PRISMA guidelines, this study gathered literature from 5 electronic databases through December 2022. This systematic review investigated both qualitative and quantitative evidence, and standardized data extraction and study quality assessments were conducted.
Results
A comprehensive search initially revealed 2,757 potentially relevant articles, 8 of which met the full inclusion criteria. Three studies investigated the phenomenon of leisure-boredom, and 5 studies assessed the experience of boredom in general and its relationship with leisure engagement. A majority of the studies, especially ones that examined older adults’ experience of overall boredom experience, lacked a thorough description of the phenomenon and did not use reliable and/or valid measurements.
Discussion and Implications
Findings from 8 articles offer insights into boredom; however, the discussion examines the limitations of these studies and reasons why studying boredom is important. We also speculate as to why little research has addressed leisure boredom among older adults and propose a research agenda for increasing our understanding of the ways older adults experience boredom, the effects boredom has on health and well-being, and how boredom can be alleviated and/or managed in the context of leisure.
A strategy to develop a nutrient-rich hybrid food using rice grains functionalized with nanocoating and bovine cells for a sustainable food system is reported. Rice grains are safe food ingredients ...with a low incidence of allergy and have a nutritional profile and structure suited for 3D cell culture. An edible coating composed of fish gelatin and food enzymes offers a high affinity between rice grains and cells and improves the structural stability of grains for increased cell capacity. The potential of rice grains as cell scaffolds is demonstrated by investigating the interactions between the coating, grains, and cells. The rice grains are transformed into a hybrid food with animal nutrients by containing organized bovine cells. We discuss the food properties and production value of this rice-based meat to evaluate its potential as a sustainable food that guarantees safety from food crises and global warming.
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•Rice grains coated with fish gelatin/enzymes have improved structural stability•Coated rice grains serve as a nutritious scaffold for the organization of cells•Bovine-cell-organized grains with rice grains and animal cells are developed•Food properties of cell-organized rice show its potential as a future food element
The development of future food is an inevitable task for sustainable humanity. Unfortunately, the future food candidates reported so far have practical limitations in terms of commercialization, such as nutritional imbalance, unfamiliar taste, and poor formability. Accordingly, this study proposes to develop a new food ingredient in which rice grains, nanocoating, and animal cells are integrated. The food properties and value of these rice-based meats are discussed, assessing their potential as sustainable food ingredients. The findings of this study provide feasible ideas for creating various types of future hybrid foods. In the future, this self-production system of grain-based hybrid foods could ensure food relief in underdeveloped countries, during war, and in space.
A novel food ingredient that can overcome humanity’s food crisis has been created. Rice grains, a common food ingredient, are coated with gelatin and food enzymes to become a home for cells that can contain many animal cells. Bovine muscle cells and fat cells grow and organize on the surface and inside the rice grain. This product is reminiscent of microbeef sushi and has a different texture, nutritional profile, and flavor than traditional rice grains.
The Liesegang pattern is a beautiful natural anisotropic patterning phenomenon observed in rocks and sandstones. This study reveals that the Liesegang pattern can induce nonlinear elasticity. Here, a ...Liesegang-patterned complex with biomineral-hydrogel repetitive layers is prepared. This Liesegang-patterned complex is obtained only when the biomineralization is performed under the supersaturated conditions. The Liesegang-patterned complex features a nonlinear elastic response, whereas a complex with a single biomineral shell shows a linear behavior, thus demonstrating that the Liesegang pattern is essential in achieving nonlinear elasticity. The stiff biomineral layers have buffered the concentrated energy on behalf of soft hydrogels, thereby exposing the hydrogel components to reduced stress and, in turn, enabling them to perform the elasticity continuously. Moreover, the nonlinear elastic Liesegang-patterned complex exhibits excellent stress relaxation to the external loading, which is the biomechanical characteristic of cartilage. This stress relaxation allows the bundle of fiber-type Liesegang-patterned complex to endure greater deformation.
Effects of Dietary Korean Mistletoe on Performance and Blood Characteristics in Broilers Kim, J.H. (National Institute of Animal Science, RDA, Cheonan, Republic of Korea); Kim, D.W. (National Institute of Animal Science, RDA, Cheonan, Republic of Korea); Kang, K.H. (National Institute of Animal Science, RDA, Cheonan, Republic of Korea) ...
Korean journal of poultry science,
(Jun 2007), Letnik:
34, Številka:
2
Journal Article
Recenzirano
The objectives of this study were to examine the effects of Korean mistletoe (KM) on performance and blood characteristics in broiler chickens. A total of four hundred eighty, 1-d-old male broiler ...chicks (Ross) were divided into 4 groups with 4 replicates of 30 birds each. The treatments were NC (antibiotics-free diet), PC (NC diet added antibiotics), 0.5% KM (NC diet added 0.5% of KM) and 1.0% KM (NC diet added 1.0% of KM), and the birds were raised for 49 days. There were no significant differences in feed intake and body weight gain among treatments. On d 49, the relative length of jejunum in 1.0% KM tended to be increased or significantly (P less than 0.05) increased compare to those of other groups. On d 35, the colony forming unit of Salmonella spp. of ceca significantly (P less than 0.05) decreased by feeding KM. The counts of lymphocyte of KM significantly (P less than 0.05) increased compare to those of the PC.
