Bio-Medical Materials and Engineering - Volume 34, issue 5

Authors: Horie, Masanori | Chiba, Ryo | Umemoto, Shota | Tajika, Masahiko

Article Type: Research Article

Abstract: BACKGROUND: Calcium phosphates including β-tricalcium phosphate (β-TCP) and hydroxyapatite (HAp) have been widely used for bone regeneration application because of their high osteoconductive activities. In addition, various kinds of inorganic ions enhance differentiation, proliferation, and mineralization of osteoblasts. However, information about the effects of silver-doped β-TCP [β-TCP (Ag)] and HAp [HAp (Ag)] particles on osteogenic differentiation is not available yet. OBJECTIVE: We focused on the impact of β-TCP (Ag) and HAp (Ag) particles on the osteogenic differentiation of MC3T3-E1 osteoblast precursor cells. METHODS: MC3T3-E1 osteoblast precursor cells were pre-treated by β-TCP (Ag) or HAp (Ag). And …then the medium was changed to differentiation medium. Subsequently, osteoblast differentiation-related markers were determined. RESULTS: We found that treatment with β-TCP (Ag) or HAp (Ag) particles increased alkaline phosphatase activity in MC3T3-E1 cells. Expression of osteoblast differentiation-related genes also increased after treatment with β-TCP (Ag) or HAp (Ag) particles, a response thought to be regulated by zinc finger-containing transcription factor osterix . The ratio of the receptor activator of nuclear factor kappa-B ligand (RANKL) to osteoprotegerin (OPG) was decreased by β-TCP (Ag) and HAp (Ag) particles. CONCLUSION: Silver doping of β-TCP and HAp particles is effective for bone regeneration. Show more

Keywords: Osteoblast, β-tricalcium phosphate, hydroxyapatite, silver, MC3T3-E1 cells

DOI: 10.3233/BME-211376

Citation: Bio-Medical Materials and Engineering, vol. 34, no. 5, pp. 385-398, 2023

Authors: Flores-Espinosa, Luis Antonio | Torres-Teran, José Federico | Sánchez-Vargas, Luis Octavio | Ortiz-Magdaleno, Marine | Gonzalez-Calderón, José Amir | Zabala-Alonso, Norma Verónica | Escobar-Barrios, Vladimir Alonso | Gutiérrez-Sanchez, Mariana | Sánchez-Balderas, Gregorio | Pérez-López, José Elías

Article Type: Research Article

Abstract: BACKGROUND: Polymerization conditions affect the physical-mechanical properties of acrylic resins used for craniofacial prostheses. OBJECTIVE: The aim of this study was to evaluate the effect of microwave polymerization on the thermomechanical properties and surface morphology of ocular prostheses fabricated with polymethyl methacrylate (PMMA). METHODS: PMMA discs were polymerized with microwave energy and with conventional heat polymerization (CHP) method. Ocular prostheses were fabricated to determine whether there were changes according to the polymerization method. The surface morphology and roughness were observed under SEM and AFM. The Vickers Hardness number (VHN) and flexural strength were measured. Thermal properties …were evaluated with TGA/DSC, and chemical composition with FTIR. RESULTS: The PMMA acrylic resin polymerized with microwave energy showed a smooth surface with some relief areas. In the internal surface of the ocular prosthesis with microwave energy the PMMA is more compact. The mean roughness values were higher and statistically significant with CHP (P < 0.05), while the surface hardness and flexural strength were higher with microwave energy (P < 0.05). CONCLUSION: There were no changes in the calorimetry with either method, TGA showed an exothermic peak around 120 °C with CHP method. PMMA polymerized with microwave energy improved the mechanical and surface properties of the ocular prostheses. Show more

Keywords: Ocular prosthesis, microwave, heat polymerization, surface properties, mechanical properties

DOI: 10.3233/BME-221433

Citation: Bio-Medical Materials and Engineering, vol. 34, no. 5, pp. 399-412, 2023

Authors: Zhang, Ying | Wang, Haijian | Kumazawa, Takashi | Ju, Dongying

Article Type: Research Article

Abstract: BACKGROUND: It is of great significance to understand the effect of the different corrosion behaviors of magnesium (Mg) alloys manufactured using different casting methods and implanted with different methods on the long-term implantation to expand the application of Mg-based biomedical implants. OBJECTIVE: The effects of four different casting and rolling speeds on the microstructure of an Mg–rare earth (Mg–Re) alloy were analyzed using electron backscatter diffraction (EBSD). METHOD: Four Mg alloys were obtained using vertical two-roll casting (TRC) at 10 m/min, 16 m/min, 24 m/min, and 30 m/min, and their microstructure, corrosion behavior and bone reaction in vivo were studied. …RESULTS: The corrosion resistance of the alloy increases with an increase in casting speed and finer grain size of the cast-rolled parts. The Mg–Re alloys with TRC-10 m/min and TRC-30 m/min were selected for animal experiments. The two Mg alloys were made into metal rods and inserted into the rat femur to simulate the effect of Mg–Re on femoral healing under an injury condition. The rods were implanted for a long time to judge the effects of the Mg–Re alloy on the body. The TRC-30 m/min implants obtained highly mature new bone tissue in the case of bone injury. CONCLUSION: The in vivo experiments showed that the corrosion resistance of the TRC-30 m/min implant was better than that of the TRC-10 m/min implant. After 32 weeks of implantation, there were no pathological changes in the liver, heart, or kidney of rats in the TRC-30 m/min group, and the cell structure was normal. Show more

Keywords: Mg–Re alloys, microstructure, corrosion resistance, in vivo

DOI: 10.3233/BME-222514

Citation: Bio-Medical Materials and Engineering, vol. 34, no. 5, pp. 413-425, 2023

Authors: He, Fan | Wang, Xinyu | Hua, Lu | Guo, Tingting

Article Type: Research Article

Abstract: BACKGROUND: The incidence rate of pulmonary artery stenosis is increasing year by year and its numerical simulation has become a key project of biomedical engineering. OBJECTIVE: The purpose of this work is to study the changes of hemodynamic parameters in patient-specific pulmonary artery stenosis. METHODS: A pulmonary artery stenosis model is established based on patient-specific computed tomography (CT) images. According to the actual anatomy of patient-specific pulmonary artery stenosis, the stenosis area is simulated using a porous medium to study its hemodynamic changes. The computational fluid dynamics (CFD) method is used to simulate the hemodynamic changes …of pulmonary artery stenosis, and to explore the mechanical characteristics between blood flow and vessel wall. RESULTS: The results suggest that the blood pressures of arterial branches increase and the pressure drop at both ends of the stenosis is higher. There is a high flow rate and wall shear stress at the stenosis. CONCLUSION: This study shows that the hemodynamic model of pulmonary artery stenosis can be accurately reconstructed by achieving numerical simulation of the local stenosis through CT images, and this work has important implications for improving the confidence of clinical diagnosis and treatment of pulmonary artery diseases. Show more

Keywords: Pulmonary artery, stenosis, porous medium, hemodynamics, numerical simulation

DOI: 10.3233/BME-222523

Citation: Bio-Medical Materials and Engineering, vol. 34, no. 5, pp. 427-437, 2023

Authors: Pacheco-Vergara, Maria Jesus | Ricci, John L. | Mijares, Dindo | Bromage, Timothy G. | Rabieh, Sasan | Coelho, Paulo G. | Witek, Lukasz

Article Type: Research Article

Abstract: BACKGROUND: While autografts to date remain the “gold standard” for bone void fillers, synthetic bone grafts have garnered attention due to their favorable advantages such as ability to be tailored in terms of their physical and chemical properties. Bioactive glass (BG), an inorganic material, has the capacity to form a strong bond with bone by forming a bone-like apatite surface, enhancing osteogenesis. Coupled with additive manufacturing (3D printing) it is possible to maximize bone regenerative properties of the BG. OBJECTIVE: The objective of this study was to synthesize and characterize 3D printed mesoporous bioactive glass (MBG), BG 45S5, …and compare to β-Tricalcium phosphate (β-TCP) based scaffolds; test cell viability and osteogenic differentiation on human osteoprogenitor cells in vitro . METHODS: MBG, BG 45S5, and β-TCP were fabricated into colloidal gel suspensions, tested with a rheometer, and manufactured into scaffolds using a 3D direct-write micro-printer. The materials were characterized in terms of microstructure and composition with Thermogravimetric Analyzer/Differential Scanning Calorimeter (TGA/DSC), Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD), Micro-Computed Tomography (μ-CT), Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDS), and Mattauch–Herzog-Inductively Coupled Plasma-Mass Spectrometry (MH-ICP-MS). RESULTS: Scaffolds were tested for cell proliferation and osteogenic differentiation using human osteoprogenitor cells. Osteogenic media was used for differentiation, and immunocytochemistry for osteogenic markers Runx-2, Collagen-I, and Osteocalcin. The cell viability results after 7 days of culture yielded significantly higher (p < 0.05) results in β-TCP scaffolds compared to BG 45S5 and MBG groups. CONCLUSION: All materials expressed osteogenic markers after 21 days of culture in expansion and osteogenic media. Show more

Keywords: 3D printing, bioglass 45S5, mesoporous bioactive glass, β-TCP, scaffolds, in vitro,osteogenic differentiation

DOI: 10.3233/BME-222524

Citation: Bio-Medical Materials and Engineering, vol. 34, no. 5, pp. 439-458, 2023

Authors: Sabouni, Kenda | Ozturk, Yetkin | Kacar, Erkan | Kose, Gamze Torun | Kok, Fatma Nese | Kazmanli, Muhammet Kursat | Urgen, Mustafa Kamil | Onder, Sakip

Article Type: Research Article

Abstract: BACKGROUND: Magnesium (Mg) enhances the bone regeneration, mineralization and attachment at the tissue/biomaterial interface. OBJECTIVE: In this study, the effect of Mg on mineralization/osseointegration was determined using (Ti,Mg)N thin film coated Ti6Al4V based plates and screws in vivo . METHODS: TiN and (Ti,Mg)N coated Ti6Al4V plates and screws were prepared using arc-PVD technique and used to fix rabbit femur fractures for 6 weeks. Then, mineralization/osseointegration was assessed by surface analysis including cell attachment, mineralization, and hydroxyapatite deposition on concave and convex sides of the plates along with the attachment between the screw and the bone. …RESULTS: According to Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS) analyses; cell attachment and mineralization were higher on the concave sides of the plates from both groups in comparison to the convex sides. However, mineralization was significantly higher on Mg-containing ones. The mean gray value indicating mineralized area after von Kossa staining was found as 0.48 ± 0.01 and 0.41 ± 0.04 on Mg containing and free ones respectively. Similarly, Fourier Transform Infrared Spectroscopy (FTIR) and X-ray diffraction (XRD) analyses showed that hydroxyapatite growth was abundant on the Mg-containing and concave sides of the plates. Enhanced mineralization and strong attachment to bone were also detected in EDS and SEM analyses of Mg-containing screws. CONCLUSION: These findings indicated that (Ti,Mg)N coatings can be used to increase attachment at the implant tissue interface due to accelerated mineralization, cell attachment, and hydroxyapatite growth. Show more

Keywords: Magnesium, mineralization, osseointegration, bone

DOI: 10.3233/BME-222544

Citation: Bio-Medical Materials and Engineering, vol. 34, no. 5, pp. 459-472, 2023

Authors: Duckworth, Chloe | Stutts, Jada | Clatterbuck, Kayla | Nosoudi, Nasim

Article Type: Research Article

Abstract: BACKGROUND: Elastin is a fibrous protein key to the structure and support of skin as well as other organ tissues. Elastic fibers are located in the skin’s dermal layer and make up approximately 2%–4% of the fat-free dry weight of the dermis in the skin of adults. Aging causes the progressive degradation of elastin fibers. Loss of these fibers can cause skin sagging and wrinkling, loss of healthy blood vessels and lung capacity, aneurysms, and Chronic Obstructive Pulmonary Disease (COPD). OBJECTIVE: We hypothesized that ellagic acid, a polyphenol, will increase elastin in human dermal fibroblasts (HDF) due to …polyphenols’ elastin binding properties. METHOD: We treated HDF’s with 2 μg/ml ellagic acid for 28 days to see the elastin deposition in HDF cell cultures. To test this, we treated HDFs with polyphenols ellagic acid for 3, 7, 14 and 21 days. For comparison purposes, we included a group of ellagic acid and retinoic acid since retinoic acid is already in the market for elastin regeneration purposes. RESULTS: When ellagic acid and retinoic acid were introduced together, insoluble elastin and collagen deposition were significantly higher in HDFs compared to other groups. CONCLUSION: Polyphenols and retinoic acid can improve skin extracellular matrix production of elastin and collagen and may improve skin fine wrinkles. Show more

Keywords: Elastogenesis, collagen, ellagic acid, retinoic acid

DOI: 10.3233/BME-230007

Citation: Bio-Medical Materials and Engineering, vol. 34, no. 5, pp. 473-480, 2023